switch GOSTD_VERSION=1.19.1

switch GOSTD_VERSION=1.19.1

1363 files changed, 212655 insertions, 204899 deletions

diff --git a/contrib/go/_std_1.18/src/bufio/bufio.go b/contrib/go/_std_1.18/src/bufio/bufio.go
deleted file mode 100644
index 7483946fc0..0000000000
--- a/contrib/go/_std_1.18/src/bufio/bufio.go
+++ /dev/null
@@ -1,813 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package bufio implements buffered I/O. It wraps an io.Reader or io.Writer
-// object, creating another object (Reader or Writer) that also implements
-// the interface but provides buffering and some help for textual I/O.
-package bufio
-
-import (
-	"bytes"
-	"errors"
-	"io"
-	"strings"
-	"unicode/utf8"
-)
-
-const (
-	defaultBufSize = 4096
-)
-
-var (
-	ErrInvalidUnreadByte = errors.New("bufio: invalid use of UnreadByte")
-	ErrInvalidUnreadRune = errors.New("bufio: invalid use of UnreadRune")
-	ErrBufferFull        = errors.New("bufio: buffer full")
-	ErrNegativeCount     = errors.New("bufio: negative count")
-)
-
-// Buffered input.
-
-// Reader implements buffering for an io.Reader object.
-type Reader struct {
-	buf          []byte
-	rd           io.Reader // reader provided by the client
-	r, w         int       // buf read and write positions
-	err          error
-	lastByte     int // last byte read for UnreadByte; -1 means invalid
-	lastRuneSize int // size of last rune read for UnreadRune; -1 means invalid
-}
-
-const minReadBufferSize = 16
-const maxConsecutiveEmptyReads = 100
-
-// NewReaderSize returns a new Reader whose buffer has at least the specified
-// size. If the argument io.Reader is already a Reader with large enough
-// size, it returns the underlying Reader.
-func NewReaderSize(rd io.Reader, size int) *Reader {
-	// Is it already a Reader?
-	b, ok := rd.(*Reader)
-	if ok && len(b.buf) >= size {
-		return b
-	}
-	if size < minReadBufferSize {
-		size = minReadBufferSize
-	}
-	r := new(Reader)
-	r.reset(make([]byte, size), rd)
-	return r
-}
-
-// NewReader returns a new Reader whose buffer has the default size.
-func NewReader(rd io.Reader) *Reader {
-	return NewReaderSize(rd, defaultBufSize)
-}
-
-// Size returns the size of the underlying buffer in bytes.
-func (b *Reader) Size() int { return len(b.buf) }
-
-// Reset discards any buffered data, resets all state, and switches
-// the buffered reader to read from r.
-// Calling Reset on the zero value of Reader initializes the internal buffer
-// to the default size.
-func (b *Reader) Reset(r io.Reader) {
-	if b.buf == nil {
-		b.buf = make([]byte, defaultBufSize)
-	}
-	b.reset(b.buf, r)
-}
-
-func (b *Reader) reset(buf []byte, r io.Reader) {
-	*b = Reader{
-		buf:          buf,
-		rd:           r,
-		lastByte:     -1,
-		lastRuneSize: -1,
-	}
-}
-
-var errNegativeRead = errors.New("bufio: reader returned negative count from Read")
-
-// fill reads a new chunk into the buffer.
-func (b *Reader) fill() {
-	// Slide existing data to beginning.
-	if b.r > 0 {
-		copy(b.buf, b.buf[b.r:b.w])
-		b.w -= b.r
-		b.r = 0
-	}
-
-	if b.w >= len(b.buf) {
-		panic("bufio: tried to fill full buffer")
-	}
-
-	// Read new data: try a limited number of times.
-	for i := maxConsecutiveEmptyReads; i > 0; i-- {
-		n, err := b.rd.Read(b.buf[b.w:])
-		if n < 0 {
-			panic(errNegativeRead)
-		}
-		b.w += n
-		if err != nil {
-			b.err = err
-			return
-		}
-		if n > 0 {
-			return
-		}
-	}
-	b.err = io.ErrNoProgress
-}
-
-func (b *Reader) readErr() error {
-	err := b.err
-	b.err = nil
-	return err
-}
-
-// Peek returns the next n bytes without advancing the reader. The bytes stop
-// being valid at the next read call. If Peek returns fewer than n bytes, it
-// also returns an error explaining why the read is short. The error is
-// ErrBufferFull if n is larger than b's buffer size.
-//
-// Calling Peek prevents a UnreadByte or UnreadRune call from succeeding
-// until the next read operation.
-func (b *Reader) Peek(n int) ([]byte, error) {
-	if n < 0 {
-		return nil, ErrNegativeCount
-	}
-
-	b.lastByte = -1
-	b.lastRuneSize = -1
-
-	for b.w-b.r < n && b.w-b.r < len(b.buf) && b.err == nil {
-		b.fill() // b.w-b.r < len(b.buf) => buffer is not full
-	}
-
-	if n > len(b.buf) {
-		return b.buf[b.r:b.w], ErrBufferFull
-	}
-
-	// 0 <= n <= len(b.buf)
-	var err error
-	if avail := b.w - b.r; avail < n {
-		// not enough data in buffer
-		n = avail
-		err = b.readErr()
-		if err == nil {
-			err = ErrBufferFull
-		}
-	}
-	return b.buf[b.r : b.r+n], err
-}
-
-// Discard skips the next n bytes, returning the number of bytes discarded.
-//
-// If Discard skips fewer than n bytes, it also returns an error.
-// If 0 <= n <= b.Buffered(), Discard is guaranteed to succeed without
-// reading from the underlying io.Reader.
-func (b *Reader) Discard(n int) (discarded int, err error) {
-	if n < 0 {
-		return 0, ErrNegativeCount
-	}
-	if n == 0 {
-		return
-	}
-
-	b.lastByte = -1
-	b.lastRuneSize = -1
-
-	remain := n
-	for {
-		skip := b.Buffered()
-		if skip == 0 {
-			b.fill()
-			skip = b.Buffered()
-		}
-		if skip > remain {
-			skip = remain
-		}
-		b.r += skip
-		remain -= skip
-		if remain == 0 {
-			return n, nil
-		}
-		if b.err != nil {
-			return n - remain, b.readErr()
-		}
-	}
-}
-
-// Read reads data into p.
-// It returns the number of bytes read into p.
-// The bytes are taken from at most one Read on the underlying Reader,
-// hence n may be less than len(p).
-// To read exactly len(p) bytes, use io.ReadFull(b, p).
-// At EOF, the count will be zero and err will be io.EOF.
-func (b *Reader) Read(p []byte) (n int, err error) {
-	n = len(p)
-	if n == 0 {
-		if b.Buffered() > 0 {
-			return 0, nil
-		}
-		return 0, b.readErr()
-	}
-	if b.r == b.w {
-		if b.err != nil {
-			return 0, b.readErr()
-		}
-		if len(p) >= len(b.buf) {
-			// Large read, empty buffer.
-			// Read directly into p to avoid copy.
-			n, b.err = b.rd.Read(p)
-			if n < 0 {
-				panic(errNegativeRead)
-			}
-			if n > 0 {
-				b.lastByte = int(p[n-1])
-				b.lastRuneSize = -1
-			}
-			return n, b.readErr()
-		}
-		// One read.
-		// Do not use b.fill, which will loop.
-		b.r = 0
-		b.w = 0
-		n, b.err = b.rd.Read(b.buf)
-		if n < 0 {
-			panic(errNegativeRead)
-		}
-		if n == 0 {
-			return 0, b.readErr()
-		}
-		b.w += n
-	}
-
-	// copy as much as we can
-	// Note: if the slice panics here, it is probably because
-	// the underlying reader returned a bad count. See issue 49795.
-	n = copy(p, b.buf[b.r:b.w])
-	b.r += n
-	b.lastByte = int(b.buf[b.r-1])
-	b.lastRuneSize = -1
-	return n, nil
-}
-
-// ReadByte reads and returns a single byte.
-// If no byte is available, returns an error.
-func (b *Reader) ReadByte() (byte, error) {
-	b.lastRuneSize = -1
-	for b.r == b.w {
-		if b.err != nil {
-			return 0, b.readErr()
-		}
-		b.fill() // buffer is empty
-	}
-	c := b.buf[b.r]
-	b.r++
-	b.lastByte = int(c)
-	return c, nil
-}
-
-// UnreadByte unreads the last byte. Only the most recently read byte can be unread.
-//
-// UnreadByte returns an error if the most recent method called on the
-// Reader was not a read operation. Notably, Peek, Discard, and WriteTo are not
-// considered read operations.
-func (b *Reader) UnreadByte() error {
-	if b.lastByte < 0 || b.r == 0 && b.w > 0 {
-		return ErrInvalidUnreadByte
-	}
-	// b.r > 0 || b.w == 0
-	if b.r > 0 {
-		b.r--
-	} else {
-		// b.r == 0 && b.w == 0
-		b.w = 1
-	}
-	b.buf[b.r] = byte(b.lastByte)
-	b.lastByte = -1
-	b.lastRuneSize = -1
-	return nil
-}
-
-// ReadRune reads a single UTF-8 encoded Unicode character and returns the
-// rune and its size in bytes. If the encoded rune is invalid, it consumes one byte
-// and returns unicode.ReplacementChar (U+FFFD) with a size of 1.
-func (b *Reader) ReadRune() (r rune, size int, err error) {
-	for b.r+utf8.UTFMax > b.w && !utf8.FullRune(b.buf[b.r:b.w]) && b.err == nil && b.w-b.r < len(b.buf) {
-		b.fill() // b.w-b.r < len(buf) => buffer is not full
-	}
-	b.lastRuneSize = -1
-	if b.r == b.w {
-		return 0, 0, b.readErr()
-	}
-	r, size = rune(b.buf[b.r]), 1
-	if r >= utf8.RuneSelf {
-		r, size = utf8.DecodeRune(b.buf[b.r:b.w])
-	}
-	b.r += size
-	b.lastByte = int(b.buf[b.r-1])
-	b.lastRuneSize = size
-	return r, size, nil
-}
-
-// UnreadRune unreads the last rune. If the most recent method called on
-// the Reader was not a ReadRune, UnreadRune returns an error. (In this
-// regard it is stricter than UnreadByte, which will unread the last byte
-// from any read operation.)
-func (b *Reader) UnreadRune() error {
-	if b.lastRuneSize < 0 || b.r < b.lastRuneSize {
-		return ErrInvalidUnreadRune
-	}
-	b.r -= b.lastRuneSize
-	b.lastByte = -1
-	b.lastRuneSize = -1
-	return nil
-}
-
-// Buffered returns the number of bytes that can be read from the current buffer.
-func (b *Reader) Buffered() int { return b.w - b.r }
-
-// ReadSlice reads until the first occurrence of delim in the input,
-// returning a slice pointing at the bytes in the buffer.
-// The bytes stop being valid at the next read.
-// If ReadSlice encounters an error before finding a delimiter,
-// it returns all the data in the buffer and the error itself (often io.EOF).
-// ReadSlice fails with error ErrBufferFull if the buffer fills without a delim.
-// Because the data returned from ReadSlice will be overwritten
-// by the next I/O operation, most clients should use
-// ReadBytes or ReadString instead.
-// ReadSlice returns err != nil if and only if line does not end in delim.
-func (b *Reader) ReadSlice(delim byte) (line []byte, err error) {
-	s := 0 // search start index
-	for {
-		// Search buffer.
-		if i := bytes.IndexByte(b.buf[b.r+s:b.w], delim); i >= 0 {
-			i += s
-			line = b.buf[b.r : b.r+i+1]
-			b.r += i + 1
-			break
-		}
-
-		// Pending error?
-		if b.err != nil {
-			line = b.buf[b.r:b.w]
-			b.r = b.w
-			err = b.readErr()
-			break
-		}
-
-		// Buffer full?
-		if b.Buffered() >= len(b.buf) {
-			b.r = b.w
-			line = b.buf
-			err = ErrBufferFull
-			break
-		}
-
-		s = b.w - b.r // do not rescan area we scanned before
-
-		b.fill() // buffer is not full
-	}
-
-	// Handle last byte, if any.
-	if i := len(line) - 1; i >= 0 {
-		b.lastByte = int(line[i])
-		b.lastRuneSize = -1
-	}
-
-	return
-}
-
-// ReadLine is a low-level line-reading primitive. Most callers should use
-// ReadBytes('\n') or ReadString('\n') instead or use a Scanner.
-//
-// ReadLine tries to return a single line, not including the end-of-line bytes.
-// If the line was too long for the buffer then isPrefix is set and the
-// beginning of the line is returned. The rest of the line will be returned
-// from future calls. isPrefix will be false when returning the last fragment
-// of the line. The returned buffer is only valid until the next call to
-// ReadLine. ReadLine either returns a non-nil line or it returns an error,
-// never both.
-//
-// The text returned from ReadLine does not include the line end ("\r\n" or "\n").
-// No indication or error is given if the input ends without a final line end.
-// Calling UnreadByte after ReadLine will always unread the last byte read
-// (possibly a character belonging to the line end) even if that byte is not
-// part of the line returned by ReadLine.
-func (b *Reader) ReadLine() (line []byte, isPrefix bool, err error) {
-	line, err = b.ReadSlice('\n')
-	if err == ErrBufferFull {
-		// Handle the case where "\r\n" straddles the buffer.
-		if len(line) > 0 && line[len(line)-1] == '\r' {
-			// Put the '\r' back on buf and drop it from line.
-			// Let the next call to ReadLine check for "\r\n".
-			if b.r == 0 {
-				// should be unreachable
-				panic("bufio: tried to rewind past start of buffer")
-			}
-			b.r--
-			line = line[:len(line)-1]
-		}
-		return line, true, nil
-	}
-
-	if len(line) == 0 {
-		if err != nil {
-			line = nil
-		}
-		return
-	}
-	err = nil
-
-	if line[len(line)-1] == '\n' {
-		drop := 1
-		if len(line) > 1 && line[len(line)-2] == '\r' {
-			drop = 2
-		}
-		line = line[:len(line)-drop]
-	}
-	return
-}
-
-// collectFragments reads until the first occurrence of delim in the input. It
-// returns (slice of full buffers, remaining bytes before delim, total number
-// of bytes in the combined first two elements, error).
-// The complete result is equal to
-// `bytes.Join(append(fullBuffers, finalFragment), nil)`, which has a
-// length of `totalLen`. The result is structured in this way to allow callers
-// to minimize allocations and copies.
-func (b *Reader) collectFragments(delim byte) (fullBuffers [][]byte, finalFragment []byte, totalLen int, err error) {
-	var frag []byte
-	// Use ReadSlice to look for delim, accumulating full buffers.
-	for {
-		var e error
-		frag, e = b.ReadSlice(delim)
-		if e == nil { // got final fragment
-			break
-		}
-		if e != ErrBufferFull { // unexpected error
-			err = e
-			break
-		}
-
-		// Make a copy of the buffer.
-		buf := make([]byte, len(frag))
-		copy(buf, frag)
-		fullBuffers = append(fullBuffers, buf)
-		totalLen += len(buf)
-	}
-
-	totalLen += len(frag)
-	return fullBuffers, frag, totalLen, err
-}
-
-// ReadBytes reads until the first occurrence of delim in the input,
-// returning a slice containing the data up to and including the delimiter.
-// If ReadBytes encounters an error before finding a delimiter,
-// it returns the data read before the error and the error itself (often io.EOF).
-// ReadBytes returns err != nil if and only if the returned data does not end in
-// delim.
-// For simple uses, a Scanner may be more convenient.
-func (b *Reader) ReadBytes(delim byte) ([]byte, error) {
-	full, frag, n, err := b.collectFragments(delim)
-	// Allocate new buffer to hold the full pieces and the fragment.
-	buf := make([]byte, n)
-	n = 0
-	// Copy full pieces and fragment in.
-	for i := range full {
-		n += copy(buf[n:], full[i])
-	}
-	copy(buf[n:], frag)
-	return buf, err
-}
-
-// ReadString reads until the first occurrence of delim in the input,
-// returning a string containing the data up to and including the delimiter.
-// If ReadString encounters an error before finding a delimiter,
-// it returns the data read before the error and the error itself (often io.EOF).
-// ReadString returns err != nil if and only if the returned data does not end in
-// delim.
-// For simple uses, a Scanner may be more convenient.
-func (b *Reader) ReadString(delim byte) (string, error) {
-	full, frag, n, err := b.collectFragments(delim)
-	// Allocate new buffer to hold the full pieces and the fragment.
-	var buf strings.Builder
-	buf.Grow(n)
-	// Copy full pieces and fragment in.
-	for _, fb := range full {
-		buf.Write(fb)
-	}
-	buf.Write(frag)
-	return buf.String(), err
-}
-
-// WriteTo implements io.WriterTo.
-// This may make multiple calls to the Read method of the underlying Reader.
-// If the underlying reader supports the WriteTo method,
-// this calls the underlying WriteTo without buffering.
-func (b *Reader) WriteTo(w io.Writer) (n int64, err error) {
-	b.lastByte = -1
-	b.lastRuneSize = -1
-
-	n, err = b.writeBuf(w)
-	if err != nil {
-		return
-	}
-
-	if r, ok := b.rd.(io.WriterTo); ok {
-		m, err := r.WriteTo(w)
-		n += m
-		return n, err
-	}
-
-	if w, ok := w.(io.ReaderFrom); ok {
-		m, err := w.ReadFrom(b.rd)
-		n += m
-		return n, err
-	}
-
-	if b.w-b.r < len(b.buf) {
-		b.fill() // buffer not full
-	}
-
-	for b.r < b.w {
-		// b.r < b.w => buffer is not empty
-		m, err := b.writeBuf(w)
-		n += m
-		if err != nil {
-			return n, err
-		}
-		b.fill() // buffer is empty
-	}
-
-	if b.err == io.EOF {
-		b.err = nil
-	}
-
-	return n, b.readErr()
-}
-
-var errNegativeWrite = errors.New("bufio: writer returned negative count from Write")
-
-// writeBuf writes the Reader's buffer to the writer.
-func (b *Reader) writeBuf(w io.Writer) (int64, error) {
-	n, err := w.Write(b.buf[b.r:b.w])
-	if n < 0 {
-		panic(errNegativeWrite)
-	}
-	b.r += n
-	return int64(n), err
-}
-
-// buffered output
-
-// Writer implements buffering for an io.Writer object.
-// If an error occurs writing to a Writer, no more data will be
-// accepted and all subsequent writes, and Flush, will return the error.
-// After all data has been written, the client should call the
-// Flush method to guarantee all data has been forwarded to
-// the underlying io.Writer.
-type Writer struct {
-	err error
-	buf []byte
-	n   int
-	wr  io.Writer
-}
-
-// NewWriterSize returns a new Writer whose buffer has at least the specified
-// size. If the argument io.Writer is already a Writer with large enough
-// size, it returns the underlying Writer.
-func NewWriterSize(w io.Writer, size int) *Writer {
-	// Is it already a Writer?
-	b, ok := w.(*Writer)
-	if ok && len(b.buf) >= size {
-		return b
-	}
-	if size <= 0 {
-		size = defaultBufSize
-	}
-	return &Writer{
-		buf: make([]byte, size),
-		wr:  w,
-	}
-}
-
-// NewWriter returns a new Writer whose buffer has the default size.
-// If the argument io.Writer is already a Writer with large enough buffer size,
-// it returns the underlying Writer.
-func NewWriter(w io.Writer) *Writer {
-	return NewWriterSize(w, defaultBufSize)
-}
-
-// Size returns the size of the underlying buffer in bytes.
-func (b *Writer) Size() int { return len(b.buf) }
-
-// Reset discards any unflushed buffered data, clears any error, and
-// resets b to write its output to w.
-// Calling Reset on the zero value of Writer initializes the internal buffer
-// to the default size.
-func (b *Writer) Reset(w io.Writer) {
-	if b.buf == nil {
-		b.buf = make([]byte, defaultBufSize)
-	}
-	b.err = nil
-	b.n = 0
-	b.wr = w
-}
-
-// Flush writes any buffered data to the underlying io.Writer.
-func (b *Writer) Flush() error {
-	if b.err != nil {
-		return b.err
-	}
-	if b.n == 0 {
-		return nil
-	}
-	n, err := b.wr.Write(b.buf[0:b.n])
-	if n < b.n && err == nil {
-		err = io.ErrShortWrite
-	}
-	if err != nil {
-		if n > 0 && n < b.n {
-			copy(b.buf[0:b.n-n], b.buf[n:b.n])
-		}
-		b.n -= n
-		b.err = err
-		return err
-	}
-	b.n = 0
-	return nil
-}
-
-// Available returns how many bytes are unused in the buffer.
-func (b *Writer) Available() int { return len(b.buf) - b.n }
-
-// AvailableBuffer returns an empty buffer with b.Available() capacity.
-// This buffer is intended to be appended to and
-// passed to an immediately succeeding Write call.
-// The buffer is only valid until the next write operation on b.
-func (b *Writer) AvailableBuffer() []byte {
-	return b.buf[b.n:][:0]
-}
-
-// Buffered returns the number of bytes that have been written into the current buffer.
-func (b *Writer) Buffered() int { return b.n }
-
-// Write writes the contents of p into the buffer.
-// It returns the number of bytes written.
-// If nn < len(p), it also returns an error explaining
-// why the write is short.
-func (b *Writer) Write(p []byte) (nn int, err error) {
-	for len(p) > b.Available() && b.err == nil {
-		var n int
-		if b.Buffered() == 0 {
-			// Large write, empty buffer.
-			// Write directly from p to avoid copy.
-			n, b.err = b.wr.Write(p)
-		} else {
-			n = copy(b.buf[b.n:], p)
-			b.n += n
-			b.Flush()
-		}
-		nn += n
-		p = p[n:]
-	}
-	if b.err != nil {
-		return nn, b.err
-	}
-	n := copy(b.buf[b.n:], p)
-	b.n += n
-	nn += n
-	return nn, nil
-}
-
-// WriteByte writes a single byte.
-func (b *Writer) WriteByte(c byte) error {
-	if b.err != nil {
-		return b.err
-	}
-	if b.Available() <= 0 && b.Flush() != nil {
-		return b.err
-	}
-	b.buf[b.n] = c
-	b.n++
-	return nil
-}
-
-// WriteRune writes a single Unicode code point, returning
-// the number of bytes written and any error.
-func (b *Writer) WriteRune(r rune) (size int, err error) {
-	// Compare as uint32 to correctly handle negative runes.
-	if uint32(r) < utf8.RuneSelf {
-		err = b.WriteByte(byte(r))
-		if err != nil {
-			return 0, err
-		}
-		return 1, nil
-	}
-	if b.err != nil {
-		return 0, b.err
-	}
-	n := b.Available()
-	if n < utf8.UTFMax {
-		if b.Flush(); b.err != nil {
-			return 0, b.err
-		}
-		n = b.Available()
-		if n < utf8.UTFMax {
-			// Can only happen if buffer is silly small.
-			return b.WriteString(string(r))
-		}
-	}
-	size = utf8.EncodeRune(b.buf[b.n:], r)
-	b.n += size
-	return size, nil
-}
-
-// WriteString writes a string.
-// It returns the number of bytes written.
-// If the count is less than len(s), it also returns an error explaining
-// why the write is short.
-func (b *Writer) WriteString(s string) (int, error) {
-	nn := 0
-	for len(s) > b.Available() && b.err == nil {
-		n := copy(b.buf[b.n:], s)
-		b.n += n
-		nn += n
-		s = s[n:]
-		b.Flush()
-	}
-	if b.err != nil {
-		return nn, b.err
-	}
-	n := copy(b.buf[b.n:], s)
-	b.n += n
-	nn += n
-	return nn, nil
-}
-
-// ReadFrom implements io.ReaderFrom. If the underlying writer
-// supports the ReadFrom method, this calls the underlying ReadFrom.
-// If there is buffered data and an underlying ReadFrom, this fills
-// the buffer and writes it before calling ReadFrom.
-func (b *Writer) ReadFrom(r io.Reader) (n int64, err error) {
-	if b.err != nil {
-		return 0, b.err
-	}
-	readerFrom, readerFromOK := b.wr.(io.ReaderFrom)
-	var m int
-	for {
-		if b.Available() == 0 {
-			if err1 := b.Flush(); err1 != nil {
-				return n, err1
-			}
-		}
-		if readerFromOK && b.Buffered() == 0 {
-			nn, err := readerFrom.ReadFrom(r)
-			b.err = err
-			n += nn
-			return n, err
-		}
-		nr := 0
-		for nr < maxConsecutiveEmptyReads {
-			m, err = r.Read(b.buf[b.n:])
-			if m != 0 || err != nil {
-				break
-			}
-			nr++
-		}
-		if nr == maxConsecutiveEmptyReads {
-			return n, io.ErrNoProgress
-		}
-		b.n += m
-		n += int64(m)
-		if err != nil {
-			break
-		}
-	}
-	if err == io.EOF {
-		// If we filled the buffer exactly, flush preemptively.
-		if b.Available() == 0 {
-			err = b.Flush()
-		} else {
-			err = nil
-		}
-	}
-	return n, err
-}
-
-// buffered input and output
-
-// ReadWriter stores pointers to a Reader and a Writer.
-// It implements io.ReadWriter.
-type ReadWriter struct {
-	*Reader
-	*Writer
-}
-
-// NewReadWriter allocates a new ReadWriter that dispatches to r and w.
-func NewReadWriter(r *Reader, w *Writer) *ReadWriter {
-	return &ReadWriter{r, w}
-}
diff --git a/contrib/go/_std_1.18/src/bufio/scan.go b/contrib/go/_std_1.18/src/bufio/scan.go
deleted file mode 100644
index 4846d4f733..0000000000
--- a/contrib/go/_std_1.18/src/bufio/scan.go
+++ /dev/null
@@ -1,420 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package bufio
-
-import (
-	"bytes"
-	"errors"
-	"io"
-	"unicode/utf8"
-)
-
-// Scanner provides a convenient interface for reading data such as
-// a file of newline-delimited lines of text. Successive calls to
-// the Scan method will step through the 'tokens' of a file, skipping
-// the bytes between the tokens. The specification of a token is
-// defined by a split function of type SplitFunc; the default split
-// function breaks the input into lines with line termination stripped. Split
-// functions are defined in this package for scanning a file into
-// lines, bytes, UTF-8-encoded runes, and space-delimited words. The
-// client may instead provide a custom split function.
-//
-// Scanning stops unrecoverably at EOF, the first I/O error, or a token too
-// large to fit in the buffer. When a scan stops, the reader may have
-// advanced arbitrarily far past the last token. Programs that need more
-// control over error handling or large tokens, or must run sequential scans
-// on a reader, should use bufio.Reader instead.
-//
-type Scanner struct {
-	r            io.Reader // The reader provided by the client.
-	split        SplitFunc // The function to split the tokens.
-	maxTokenSize int       // Maximum size of a token; modified by tests.
-	token        []byte    // Last token returned by split.
-	buf          []byte    // Buffer used as argument to split.
-	start        int       // First non-processed byte in buf.
-	end          int       // End of data in buf.
-	err          error     // Sticky error.
-	empties      int       // Count of successive empty tokens.
-	scanCalled   bool      // Scan has been called; buffer is in use.
-	done         bool      // Scan has finished.
-}
-
-// SplitFunc is the signature of the split function used to tokenize the
-// input. The arguments are an initial substring of the remaining unprocessed
-// data and a flag, atEOF, that reports whether the Reader has no more data
-// to give. The return values are the number of bytes to advance the input
-// and the next token to return to the user, if any, plus an error, if any.
-//
-// Scanning stops if the function returns an error, in which case some of
-// the input may be discarded. If that error is ErrFinalToken, scanning
-// stops with no error.
-//
-// Otherwise, the Scanner advances the input. If the token is not nil,
-// the Scanner returns it to the user. If the token is nil, the
-// Scanner reads more data and continues scanning; if there is no more
-// data--if atEOF was true--the Scanner returns. If the data does not
-// yet hold a complete token, for instance if it has no newline while
-// scanning lines, a SplitFunc can return (0, nil, nil) to signal the
-// Scanner to read more data into the slice and try again with a
-// longer slice starting at the same point in the input.
-//
-// The function is never called with an empty data slice unless atEOF
-// is true. If atEOF is true, however, data may be non-empty and,
-// as always, holds unprocessed text.
-type SplitFunc func(data []byte, atEOF bool) (advance int, token []byte, err error)
-
-// Errors returned by Scanner.
-var (
-	ErrTooLong         = errors.New("bufio.Scanner: token too long")
-	ErrNegativeAdvance = errors.New("bufio.Scanner: SplitFunc returns negative advance count")
-	ErrAdvanceTooFar   = errors.New("bufio.Scanner: SplitFunc returns advance count beyond input")
-	ErrBadReadCount    = errors.New("bufio.Scanner: Read returned impossible count")
-)
-
-const (
-	// MaxScanTokenSize is the maximum size used to buffer a token
-	// unless the user provides an explicit buffer with Scanner.Buffer.
-	// The actual maximum token size may be smaller as the buffer
-	// may need to include, for instance, a newline.
-	MaxScanTokenSize = 64 * 1024
-
-	startBufSize = 4096 // Size of initial allocation for buffer.
-)
-
-// NewScanner returns a new Scanner to read from r.
-// The split function defaults to ScanLines.
-func NewScanner(r io.Reader) *Scanner {
-	return &Scanner{
-		r:            r,
-		split:        ScanLines,
-		maxTokenSize: MaxScanTokenSize,
-	}
-}
-
-// Err returns the first non-EOF error that was encountered by the Scanner.
-func (s *Scanner) Err() error {
-	if s.err == io.EOF {
-		return nil
-	}
-	return s.err
-}
-
-// Bytes returns the most recent token generated by a call to Scan.
-// The underlying array may point to data that will be overwritten
-// by a subsequent call to Scan. It does no allocation.
-func (s *Scanner) Bytes() []byte {
-	return s.token
-}
-
-// Text returns the most recent token generated by a call to Scan
-// as a newly allocated string holding its bytes.
-func (s *Scanner) Text() string {
-	return string(s.token)
-}
-
-// ErrFinalToken is a special sentinel error value. It is intended to be
-// returned by a Split function to indicate that the token being delivered
-// with the error is the last token and scanning should stop after this one.
-// After ErrFinalToken is received by Scan, scanning stops with no error.
-// The value is useful to stop processing early or when it is necessary to
-// deliver a final empty token. One could achieve the same behavior
-// with a custom error value but providing one here is tidier.
-// See the emptyFinalToken example for a use of this value.
-var ErrFinalToken = errors.New("final token")
-
-// Scan advances the Scanner to the next token, which will then be
-// available through the Bytes or Text method. It returns false when the
-// scan stops, either by reaching the end of the input or an error.
-// After Scan returns false, the Err method will return any error that
-// occurred during scanning, except that if it was io.EOF, Err
-// will return nil.
-// Scan panics if the split function returns too many empty
-// tokens without advancing the input. This is a common error mode for
-// scanners.
-func (s *Scanner) Scan() bool {
-	if s.done {
-		return false
-	}
-	s.scanCalled = true
-	// Loop until we have a token.
-	for {
-		// See if we can get a token with what we already have.
-		// If we've run out of data but have an error, give the split function
-		// a chance to recover any remaining, possibly empty token.
-		if s.end > s.start || s.err != nil {
-			advance, token, err := s.split(s.buf[s.start:s.end], s.err != nil)
-			if err != nil {
-				if err == ErrFinalToken {
-					s.token = token
-					s.done = true
-					return true
-				}
-				s.setErr(err)
-				return false
-			}
-			if !s.advance(advance) {
-				return false
-			}
-			s.token = token
-			if token != nil {
-				if s.err == nil || advance > 0 {
-					s.empties = 0
-				} else {
-					// Returning tokens not advancing input at EOF.
-					s.empties++
-					if s.empties > maxConsecutiveEmptyReads {
-						panic("bufio.Scan: too many empty tokens without progressing")
-					}
-				}
-				return true
-			}
-		}
-		// We cannot generate a token with what we are holding.
-		// If we've already hit EOF or an I/O error, we are done.
-		if s.err != nil {
-			// Shut it down.
-			s.start = 0
-			s.end = 0
-			return false
-		}
-		// Must read more data.
-		// First, shift data to beginning of buffer if there's lots of empty space
-		// or space is needed.
-		if s.start > 0 && (s.end == len(s.buf) || s.start > len(s.buf)/2) {
-			copy(s.buf, s.buf[s.start:s.end])
-			s.end -= s.start
-			s.start = 0
-		}
-		// Is the buffer full? If so, resize.
-		if s.end == len(s.buf) {
-			// Guarantee no overflow in the multiplication below.
-			const maxInt = int(^uint(0) >> 1)
-			if len(s.buf) >= s.maxTokenSize || len(s.buf) > maxInt/2 {
-				s.setErr(ErrTooLong)
-				return false
-			}
-			newSize := len(s.buf) * 2
-			if newSize == 0 {
-				newSize = startBufSize
-			}
-			if newSize > s.maxTokenSize {
-				newSize = s.maxTokenSize
-			}
-			newBuf := make([]byte, newSize)
-			copy(newBuf, s.buf[s.start:s.end])
-			s.buf = newBuf
-			s.end -= s.start
-			s.start = 0
-		}
-		// Finally we can read some input. Make sure we don't get stuck with
-		// a misbehaving Reader. Officially we don't need to do this, but let's
-		// be extra careful: Scanner is for safe, simple jobs.
-		for loop := 0; ; {
-			n, err := s.r.Read(s.buf[s.end:len(s.buf)])
-			if n < 0 || len(s.buf)-s.end < n {
-				s.setErr(ErrBadReadCount)
-				break
-			}
-			s.end += n
-			if err != nil {
-				s.setErr(err)
-				break
-			}
-			if n > 0 {
-				s.empties = 0
-				break
-			}
-			loop++
-			if loop > maxConsecutiveEmptyReads {
-				s.setErr(io.ErrNoProgress)
-				break
-			}
-		}
-	}
-}
-
-// advance consumes n bytes of the buffer. It reports whether the advance was legal.
-func (s *Scanner) advance(n int) bool {
-	if n < 0 {
-		s.setErr(ErrNegativeAdvance)
-		return false
-	}
-	if n > s.end-s.start {
-		s.setErr(ErrAdvanceTooFar)
-		return false
-	}
-	s.start += n
-	return true
-}
-
-// setErr records the first error encountered.
-func (s *Scanner) setErr(err error) {
-	if s.err == nil || s.err == io.EOF {
-		s.err = err
-	}
-}
-
-// Buffer sets the initial buffer to use when scanning and the maximum
-// size of buffer that may be allocated during scanning. The maximum
-// token size is the larger of max and cap(buf). If max <= cap(buf),
-// Scan will use this buffer only and do no allocation.
-//
-// By default, Scan uses an internal buffer and sets the
-// maximum token size to MaxScanTokenSize.
-//
-// Buffer panics if it is called after scanning has started.
-func (s *Scanner) Buffer(buf []byte, max int) {
-	if s.scanCalled {
-		panic("Buffer called after Scan")
-	}
-	s.buf = buf[0:cap(buf)]
-	s.maxTokenSize = max
-}
-
-// Split sets the split function for the Scanner.
-// The default split function is ScanLines.
-//
-// Split panics if it is called after scanning has started.
-func (s *Scanner) Split(split SplitFunc) {
-	if s.scanCalled {
-		panic("Split called after Scan")
-	}
-	s.split = split
-}
-
-// Split functions
-
-// ScanBytes is a split function for a Scanner that returns each byte as a token.
-func ScanBytes(data []byte, atEOF bool) (advance int, token []byte, err error) {
-	if atEOF && len(data) == 0 {
-		return 0, nil, nil
-	}
-	return 1, data[0:1], nil
-}
-
-var errorRune = []byte(string(utf8.RuneError))
-
-// ScanRunes is a split function for a Scanner that returns each
-// UTF-8-encoded rune as a token. The sequence of runes returned is
-// equivalent to that from a range loop over the input as a string, which
-// means that erroneous UTF-8 encodings translate to U+FFFD = "\xef\xbf\xbd".
-// Because of the Scan interface, this makes it impossible for the client to
-// distinguish correctly encoded replacement runes from encoding errors.
-func ScanRunes(data []byte, atEOF bool) (advance int, token []byte, err error) {
-	if atEOF && len(data) == 0 {
-		return 0, nil, nil
-	}
-
-	// Fast path 1: ASCII.
-	if data[0] < utf8.RuneSelf {
-		return 1, data[0:1], nil
-	}
-
-	// Fast path 2: Correct UTF-8 decode without error.
-	_, width := utf8.DecodeRune(data)
-	if width > 1 {
-		// It's a valid encoding. Width cannot be one for a correctly encoded
-		// non-ASCII rune.
-		return width, data[0:width], nil
-	}
-
-	// We know it's an error: we have width==1 and implicitly r==utf8.RuneError.
-	// Is the error because there wasn't a full rune to be decoded?
-	// FullRune distinguishes correctly between erroneous and incomplete encodings.
-	if !atEOF && !utf8.FullRune(data) {
-		// Incomplete; get more bytes.
-		return 0, nil, nil
-	}
-
-	// We have a real UTF-8 encoding error. Return a properly encoded error rune
-	// but advance only one byte. This matches the behavior of a range loop over
-	// an incorrectly encoded string.
-	return 1, errorRune, nil
-}
-
-// dropCR drops a terminal \r from the data.
-func dropCR(data []byte) []byte {
-	if len(data) > 0 && data[len(data)-1] == '\r' {
-		return data[0 : len(data)-1]
-	}
-	return data
-}
-
-// ScanLines is a split function for a Scanner that returns each line of
-// text, stripped of any trailing end-of-line marker. The returned line may
-// be empty. The end-of-line marker is one optional carriage return followed
-// by one mandatory newline. In regular expression notation, it is `\r?\n`.
-// The last non-empty line of input will be returned even if it has no
-// newline.
-func ScanLines(data []byte, atEOF bool) (advance int, token []byte, err error) {
-	if atEOF && len(data) == 0 {
-		return 0, nil, nil
-	}
-	if i := bytes.IndexByte(data, '\n'); i >= 0 {
-		// We have a full newline-terminated line.
-		return i + 1, dropCR(data[0:i]), nil
-	}
-	// If we're at EOF, we have a final, non-terminated line. Return it.
-	if atEOF {
-		return len(data), dropCR(data), nil
-	}
-	// Request more data.
-	return 0, nil, nil
-}
-
-// isSpace reports whether the character is a Unicode white space character.
-// We avoid dependency on the unicode package, but check validity of the implementation
-// in the tests.
-func isSpace(r rune) bool {
-	if r <= '\u00FF' {
-		// Obvious ASCII ones: \t through \r plus space. Plus two Latin-1 oddballs.
-		switch r {
-		case ' ', '\t', '\n', '\v', '\f', '\r':
-			return true
-		case '\u0085', '\u00A0':
-			return true
-		}
-		return false
-	}
-	// High-valued ones.
-	if '\u2000' <= r && r <= '\u200a' {
-		return true
-	}
-	switch r {
-	case '\u1680', '\u2028', '\u2029', '\u202f', '\u205f', '\u3000':
-		return true
-	}
-	return false
-}
-
-// ScanWords is a split function for a Scanner that returns each
-// space-separated word of text, with surrounding spaces deleted. It will
-// never return an empty string. The definition of space is set by
-// unicode.IsSpace.
-func ScanWords(data []byte, atEOF bool) (advance int, token []byte, err error) {
-	// Skip leading spaces.
-	start := 0
-	for width := 0; start < len(data); start += width {
-		var r rune
-		r, width = utf8.DecodeRune(data[start:])
-		if !isSpace(r) {
-			break
-		}
-	}
-	// Scan until space, marking end of word.
-	for width, i := 0, start; i < len(data); i += width {
-		var r rune
-		r, width = utf8.DecodeRune(data[i:])
-		if isSpace(r) {
-			return i + width, data[start:i], nil
-		}
-	}
-	// If we're at EOF, we have a final, non-empty, non-terminated word. Return it.
-	if atEOF && len(data) > start {
-		return len(data), data[start:], nil
-	}
-	// Request more data.
-	return start, nil, nil
-}
diff --git a/contrib/go/_std_1.18/src/bytes/buffer.go b/contrib/go/_std_1.18/src/bytes/buffer.go
deleted file mode 100644
index 549b077708..0000000000
--- a/contrib/go/_std_1.18/src/bytes/buffer.go
+++ /dev/null
@@ -1,461 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package bytes
-
-// Simple byte buffer for marshaling data.
-
-import (
-	"errors"
-	"io"
-	"unicode/utf8"
-)
-
-// smallBufferSize is an initial allocation minimal capacity.
-const smallBufferSize = 64
-
-// A Buffer is a variable-sized buffer of bytes with Read and Write methods.
-// The zero value for Buffer is an empty buffer ready to use.
-type Buffer struct {
-	buf      []byte // contents are the bytes buf[off : len(buf)]
-	off      int    // read at &buf[off], write at &buf[len(buf)]
-	lastRead readOp // last read operation, so that Unread* can work correctly.
-}
-
-// The readOp constants describe the last action performed on
-// the buffer, so that UnreadRune and UnreadByte can check for
-// invalid usage. opReadRuneX constants are chosen such that
-// converted to int they correspond to the rune size that was read.
-type readOp int8
-
-// Don't use iota for these, as the values need to correspond with the
-// names and comments, which is easier to see when being explicit.
-const (
-	opRead      readOp = -1 // Any other read operation.
-	opInvalid   readOp = 0  // Non-read operation.
-	opReadRune1 readOp = 1  // Read rune of size 1.
-	opReadRune2 readOp = 2  // Read rune of size 2.
-	opReadRune3 readOp = 3  // Read rune of size 3.
-	opReadRune4 readOp = 4  // Read rune of size 4.
-)
-
-// ErrTooLarge is passed to panic if memory cannot be allocated to store data in a buffer.
-var ErrTooLarge = errors.New("bytes.Buffer: too large")
-var errNegativeRead = errors.New("bytes.Buffer: reader returned negative count from Read")
-
-const maxInt = int(^uint(0) >> 1)
-
-// Bytes returns a slice of length b.Len() holding the unread portion of the buffer.
-// The slice is valid for use only until the next buffer modification (that is,
-// only until the next call to a method like Read, Write, Reset, or Truncate).
-// The slice aliases the buffer content at least until the next buffer modification,
-// so immediate changes to the slice will affect the result of future reads.
-func (b *Buffer) Bytes() []byte { return b.buf[b.off:] }
-
-// String returns the contents of the unread portion of the buffer
-// as a string. If the Buffer is a nil pointer, it returns "<nil>".
-//
-// To build strings more efficiently, see the strings.Builder type.
-func (b *Buffer) String() string {
-	if b == nil {
-		// Special case, useful in debugging.
-		return "<nil>"
-	}
-	return string(b.buf[b.off:])
-}
-
-// empty reports whether the unread portion of the buffer is empty.
-func (b *Buffer) empty() bool { return len(b.buf) <= b.off }
-
-// Len returns the number of bytes of the unread portion of the buffer;
-// b.Len() == len(b.Bytes()).
-func (b *Buffer) Len() int { return len(b.buf) - b.off }
-
-// Cap returns the capacity of the buffer's underlying byte slice, that is, the
-// total space allocated for the buffer's data.
-func (b *Buffer) Cap() int { return cap(b.buf) }
-
-// Truncate discards all but the first n unread bytes from the buffer
-// but continues to use the same allocated storage.
-// It panics if n is negative or greater than the length of the buffer.
-func (b *Buffer) Truncate(n int) {
-	if n == 0 {
-		b.Reset()
-		return
-	}
-	b.lastRead = opInvalid
-	if n < 0 || n > b.Len() {
-		panic("bytes.Buffer: truncation out of range")
-	}
-	b.buf = b.buf[:b.off+n]
-}
-
-// Reset resets the buffer to be empty,
-// but it retains the underlying storage for use by future writes.
-// Reset is the same as Truncate(0).
-func (b *Buffer) Reset() {
-	b.buf = b.buf[:0]
-	b.off = 0
-	b.lastRead = opInvalid
-}
-
-// tryGrowByReslice is a inlineable version of grow for the fast-case where the
-// internal buffer only needs to be resliced.
-// It returns the index where bytes should be written and whether it succeeded.
-func (b *Buffer) tryGrowByReslice(n int) (int, bool) {
-	if l := len(b.buf); n <= cap(b.buf)-l {
-		b.buf = b.buf[:l+n]
-		return l, true
-	}
-	return 0, false
-}
-
-// grow grows the buffer to guarantee space for n more bytes.
-// It returns the index where bytes should be written.
-// If the buffer can't grow it will panic with ErrTooLarge.
-func (b *Buffer) grow(n int) int {
-	m := b.Len()
-	// If buffer is empty, reset to recover space.
-	if m == 0 && b.off != 0 {
-		b.Reset()
-	}
-	// Try to grow by means of a reslice.
-	if i, ok := b.tryGrowByReslice(n); ok {
-		return i
-	}
-	if b.buf == nil && n <= smallBufferSize {
-		b.buf = make([]byte, n, smallBufferSize)
-		return 0
-	}
-	c := cap(b.buf)
-	if n <= c/2-m {
-		// We can slide things down instead of allocating a new
-		// slice. We only need m+n <= c to slide, but
-		// we instead let capacity get twice as large so we
-		// don't spend all our time copying.
-		copy(b.buf, b.buf[b.off:])
-	} else if c > maxInt-c-n {
-		panic(ErrTooLarge)
-	} else {
-		// Not enough space anywhere, we need to allocate.
-		buf := makeSlice(2*c + n)
-		copy(buf, b.buf[b.off:])
-		b.buf = buf
-	}
-	// Restore b.off and len(b.buf).
-	b.off = 0
-	b.buf = b.buf[:m+n]
-	return m
-}
-
-// Grow grows the buffer's capacity, if necessary, to guarantee space for
-// another n bytes. After Grow(n), at least n bytes can be written to the
-// buffer without another allocation.
-// If n is negative, Grow will panic.
-// If the buffer can't grow it will panic with ErrTooLarge.
-func (b *Buffer) Grow(n int) {
-	if n < 0 {
-		panic("bytes.Buffer.Grow: negative count")
-	}
-	m := b.grow(n)
-	b.buf = b.buf[:m]
-}
-
-// Write appends the contents of p to the buffer, growing the buffer as
-// needed. The return value n is the length of p; err is always nil. If the
-// buffer becomes too large, Write will panic with ErrTooLarge.
-func (b *Buffer) Write(p []byte) (n int, err error) {
-	b.lastRead = opInvalid
-	m, ok := b.tryGrowByReslice(len(p))
-	if !ok {
-		m = b.grow(len(p))
-	}
-	return copy(b.buf[m:], p), nil
-}
-
-// WriteString appends the contents of s to the buffer, growing the buffer as
-// needed. The return value n is the length of s; err is always nil. If the
-// buffer becomes too large, WriteString will panic with ErrTooLarge.
-func (b *Buffer) WriteString(s string) (n int, err error) {
-	b.lastRead = opInvalid
-	m, ok := b.tryGrowByReslice(len(s))
-	if !ok {
-		m = b.grow(len(s))
-	}
-	return copy(b.buf[m:], s), nil
-}
-
-// MinRead is the minimum slice size passed to a Read call by
-// Buffer.ReadFrom. As long as the Buffer has at least MinRead bytes beyond
-// what is required to hold the contents of r, ReadFrom will not grow the
-// underlying buffer.
-const MinRead = 512
-
-// ReadFrom reads data from r until EOF and appends it to the buffer, growing
-// the buffer as needed. The return value n is the number of bytes read. Any
-// error except io.EOF encountered during the read is also returned. If the
-// buffer becomes too large, ReadFrom will panic with ErrTooLarge.
-func (b *Buffer) ReadFrom(r io.Reader) (n int64, err error) {
-	b.lastRead = opInvalid
-	for {
-		i := b.grow(MinRead)
-		b.buf = b.buf[:i]
-		m, e := r.Read(b.buf[i:cap(b.buf)])
-		if m < 0 {
-			panic(errNegativeRead)
-		}
-
-		b.buf = b.buf[:i+m]
-		n += int64(m)
-		if e == io.EOF {
-			return n, nil // e is EOF, so return nil explicitly
-		}
-		if e != nil {
-			return n, e
-		}
-	}
-}
-
-// makeSlice allocates a slice of size n. If the allocation fails, it panics
-// with ErrTooLarge.
-func makeSlice(n int) []byte {
-	// If the make fails, give a known error.
-	defer func() {
-		if recover() != nil {
-			panic(ErrTooLarge)
-		}
-	}()
-	return make([]byte, n)
-}
-
-// WriteTo writes data to w until the buffer is drained or an error occurs.
-// The return value n is the number of bytes written; it always fits into an
-// int, but it is int64 to match the io.WriterTo interface. Any error
-// encountered during the write is also returned.
-func (b *Buffer) WriteTo(w io.Writer) (n int64, err error) {
-	b.lastRead = opInvalid
-	if nBytes := b.Len(); nBytes > 0 {
-		m, e := w.Write(b.buf[b.off:])
-		if m > nBytes {
-			panic("bytes.Buffer.WriteTo: invalid Write count")
-		}
-		b.off += m
-		n = int64(m)
-		if e != nil {
-			return n, e
-		}
-		// all bytes should have been written, by definition of
-		// Write method in io.Writer
-		if m != nBytes {
-			return n, io.ErrShortWrite
-		}
-	}
-	// Buffer is now empty; reset.
-	b.Reset()
-	return n, nil
-}
-
-// WriteByte appends the byte c to the buffer, growing the buffer as needed.
-// The returned error is always nil, but is included to match bufio.Writer's
-// WriteByte. If the buffer becomes too large, WriteByte will panic with
-// ErrTooLarge.
-func (b *Buffer) WriteByte(c byte) error {
-	b.lastRead = opInvalid
-	m, ok := b.tryGrowByReslice(1)
-	if !ok {
-		m = b.grow(1)
-	}
-	b.buf[m] = c
-	return nil
-}
-
-// WriteRune appends the UTF-8 encoding of Unicode code point r to the
-// buffer, returning its length and an error, which is always nil but is
-// included to match bufio.Writer's WriteRune. The buffer is grown as needed;
-// if it becomes too large, WriteRune will panic with ErrTooLarge.
-func (b *Buffer) WriteRune(r rune) (n int, err error) {
-	// Compare as uint32 to correctly handle negative runes.
-	if uint32(r) < utf8.RuneSelf {
-		b.WriteByte(byte(r))
-		return 1, nil
-	}
-	b.lastRead = opInvalid
-	m, ok := b.tryGrowByReslice(utf8.UTFMax)
-	if !ok {
-		m = b.grow(utf8.UTFMax)
-	}
-	n = utf8.EncodeRune(b.buf[m:m+utf8.UTFMax], r)
-	b.buf = b.buf[:m+n]
-	return n, nil
-}
-
-// Read reads the next len(p) bytes from the buffer or until the buffer
-// is drained. The return value n is the number of bytes read. If the
-// buffer has no data to return, err is io.EOF (unless len(p) is zero);
-// otherwise it is nil.
-func (b *Buffer) Read(p []byte) (n int, err error) {
-	b.lastRead = opInvalid
-	if b.empty() {
-		// Buffer is empty, reset to recover space.
-		b.Reset()
-		if len(p) == 0 {
-			return 0, nil
-		}
-		return 0, io.EOF
-	}
-	n = copy(p, b.buf[b.off:])
-	b.off += n
-	if n > 0 {
-		b.lastRead = opRead
-	}
-	return n, nil
-}
-
-// Next returns a slice containing the next n bytes from the buffer,
-// advancing the buffer as if the bytes had been returned by Read.
-// If there are fewer than n bytes in the buffer, Next returns the entire buffer.
-// The slice is only valid until the next call to a read or write method.
-func (b *Buffer) Next(n int) []byte {
-	b.lastRead = opInvalid
-	m := b.Len()
-	if n > m {
-		n = m
-	}
-	data := b.buf[b.off : b.off+n]
-	b.off += n
-	if n > 0 {
-		b.lastRead = opRead
-	}
-	return data
-}
-
-// ReadByte reads and returns the next byte from the buffer.
-// If no byte is available, it returns error io.EOF.
-func (b *Buffer) ReadByte() (byte, error) {
-	if b.empty() {
-		// Buffer is empty, reset to recover space.
-		b.Reset()
-		return 0, io.EOF
-	}
-	c := b.buf[b.off]
-	b.off++
-	b.lastRead = opRead
-	return c, nil
-}
-
-// ReadRune reads and returns the next UTF-8-encoded
-// Unicode code point from the buffer.
-// If no bytes are available, the error returned is io.EOF.
-// If the bytes are an erroneous UTF-8 encoding, it
-// consumes one byte and returns U+FFFD, 1.
-func (b *Buffer) ReadRune() (r rune, size int, err error) {
-	if b.empty() {
-		// Buffer is empty, reset to recover space.
-		b.Reset()
-		return 0, 0, io.EOF
-	}
-	c := b.buf[b.off]
-	if c < utf8.RuneSelf {
-		b.off++
-		b.lastRead = opReadRune1
-		return rune(c), 1, nil
-	}
-	r, n := utf8.DecodeRune(b.buf[b.off:])
-	b.off += n
-	b.lastRead = readOp(n)
-	return r, n, nil
-}
-
-// UnreadRune unreads the last rune returned by ReadRune.
-// If the most recent read or write operation on the buffer was
-// not a successful ReadRune, UnreadRune returns an error.  (In this regard
-// it is stricter than UnreadByte, which will unread the last byte
-// from any read operation.)
-func (b *Buffer) UnreadRune() error {
-	if b.lastRead <= opInvalid {
-		return errors.New("bytes.Buffer: UnreadRune: previous operation was not a successful ReadRune")
-	}
-	if b.off >= int(b.lastRead) {
-		b.off -= int(b.lastRead)
-	}
-	b.lastRead = opInvalid
-	return nil
-}
-
-var errUnreadByte = errors.New("bytes.Buffer: UnreadByte: previous operation was not a successful read")
-
-// UnreadByte unreads the last byte returned by the most recent successful
-// read operation that read at least one byte. If a write has happened since
-// the last read, if the last read returned an error, or if the read read zero
-// bytes, UnreadByte returns an error.
-func (b *Buffer) UnreadByte() error {
-	if b.lastRead == opInvalid {
-		return errUnreadByte
-	}
-	b.lastRead = opInvalid
-	if b.off > 0 {
-		b.off--
-	}
-	return nil
-}
-
-// ReadBytes reads until the first occurrence of delim in the input,
-// returning a slice containing the data up to and including the delimiter.
-// If ReadBytes encounters an error before finding a delimiter,
-// it returns the data read before the error and the error itself (often io.EOF).
-// ReadBytes returns err != nil if and only if the returned data does not end in
-// delim.
-func (b *Buffer) ReadBytes(delim byte) (line []byte, err error) {
-	slice, err := b.readSlice(delim)
-	// return a copy of slice. The buffer's backing array may
-	// be overwritten by later calls.
-	line = append(line, slice...)
-	return line, err
-}
-
-// readSlice is like ReadBytes but returns a reference to internal buffer data.
-func (b *Buffer) readSlice(delim byte) (line []byte, err error) {
-	i := IndexByte(b.buf[b.off:], delim)
-	end := b.off + i + 1
-	if i < 0 {
-		end = len(b.buf)
-		err = io.EOF
-	}
-	line = b.buf[b.off:end]
-	b.off = end
-	b.lastRead = opRead
-	return line, err
-}
-
-// ReadString reads until the first occurrence of delim in the input,
-// returning a string containing the data up to and including the delimiter.
-// If ReadString encounters an error before finding a delimiter,
-// it returns the data read before the error and the error itself (often io.EOF).
-// ReadString returns err != nil if and only if the returned data does not end
-// in delim.
-func (b *Buffer) ReadString(delim byte) (line string, err error) {
-	slice, err := b.readSlice(delim)
-	return string(slice), err
-}
-
-// NewBuffer creates and initializes a new Buffer using buf as its
-// initial contents. The new Buffer takes ownership of buf, and the
-// caller should not use buf after this call. NewBuffer is intended to
-// prepare a Buffer to read existing data. It can also be used to set
-// the initial size of the internal buffer for writing. To do that,
-// buf should have the desired capacity but a length of zero.
-//
-// In most cases, new(Buffer) (or just declaring a Buffer variable) is
-// sufficient to initialize a Buffer.
-func NewBuffer(buf []byte) *Buffer { return &Buffer{buf: buf} }
-
-// NewBufferString creates and initializes a new Buffer using string s as its
-// initial contents. It is intended to prepare a buffer to read an existing
-// string.
-//
-// In most cases, new(Buffer) (or just declaring a Buffer variable) is
-// sufficient to initialize a Buffer.
-func NewBufferString(s string) *Buffer {
-	return &Buffer{buf: []byte(s)}
-}
diff --git a/contrib/go/_std_1.18/src/bytes/bytes.go b/contrib/go/_std_1.18/src/bytes/bytes.go
deleted file mode 100644
index e3dab4d035..0000000000
--- a/contrib/go/_std_1.18/src/bytes/bytes.go
+++ /dev/null
@@ -1,1296 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package bytes implements functions for the manipulation of byte slices.
-// It is analogous to the facilities of the strings package.
-package bytes
-
-import (
-	"internal/bytealg"
-	"unicode"
-	"unicode/utf8"
-)
-
-// Equal reports whether a and b
-// are the same length and contain the same bytes.
-// A nil argument is equivalent to an empty slice.
-func Equal(a, b []byte) bool {
-	// Neither cmd/compile nor gccgo allocates for these string conversions.
-	return string(a) == string(b)
-}
-
-// Compare returns an integer comparing two byte slices lexicographically.
-// The result will be 0 if a == b, -1 if a < b, and +1 if a > b.
-// A nil argument is equivalent to an empty slice.
-func Compare(a, b []byte) int {
-	return bytealg.Compare(a, b)
-}
-
-// explode splits s into a slice of UTF-8 sequences, one per Unicode code point (still slices of bytes),
-// up to a maximum of n byte slices. Invalid UTF-8 sequences are chopped into individual bytes.
-func explode(s []byte, n int) [][]byte {
-	if n <= 0 {
-		n = len(s)
-	}
-	a := make([][]byte, n)
-	var size int
-	na := 0
-	for len(s) > 0 {
-		if na+1 >= n {
-			a[na] = s
-			na++
-			break
-		}
-		_, size = utf8.DecodeRune(s)
-		a[na] = s[0:size:size]
-		s = s[size:]
-		na++
-	}
-	return a[0:na]
-}
-
-// Count counts the number of non-overlapping instances of sep in s.
-// If sep is an empty slice, Count returns 1 + the number of UTF-8-encoded code points in s.
-func Count(s, sep []byte) int {
-	// special case
-	if len(sep) == 0 {
-		return utf8.RuneCount(s) + 1
-	}
-	if len(sep) == 1 {
-		return bytealg.Count(s, sep[0])
-	}
-	n := 0
-	for {
-		i := Index(s, sep)
-		if i == -1 {
-			return n
-		}
-		n++
-		s = s[i+len(sep):]
-	}
-}
-
-// Contains reports whether subslice is within b.
-func Contains(b, subslice []byte) bool {
-	return Index(b, subslice) != -1
-}
-
-// ContainsAny reports whether any of the UTF-8-encoded code points in chars are within b.
-func ContainsAny(b []byte, chars string) bool {
-	return IndexAny(b, chars) >= 0
-}
-
-// ContainsRune reports whether the rune is contained in the UTF-8-encoded byte slice b.
-func ContainsRune(b []byte, r rune) bool {
-	return IndexRune(b, r) >= 0
-}
-
-// IndexByte returns the index of the first instance of c in b, or -1 if c is not present in b.
-func IndexByte(b []byte, c byte) int {
-	return bytealg.IndexByte(b, c)
-}
-
-func indexBytePortable(s []byte, c byte) int {
-	for i, b := range s {
-		if b == c {
-			return i
-		}
-	}
-	return -1
-}
-
-// LastIndex returns the index of the last instance of sep in s, or -1 if sep is not present in s.
-func LastIndex(s, sep []byte) int {
-	n := len(sep)
-	switch {
-	case n == 0:
-		return len(s)
-	case n == 1:
-		return LastIndexByte(s, sep[0])
-	case n == len(s):
-		if Equal(s, sep) {
-			return 0
-		}
-		return -1
-	case n > len(s):
-		return -1
-	}
-	// Rabin-Karp search from the end of the string
-	hashss, pow := bytealg.HashStrRevBytes(sep)
-	last := len(s) - n
-	var h uint32
-	for i := len(s) - 1; i >= last; i-- {
-		h = h*bytealg.PrimeRK + uint32(s[i])
-	}
-	if h == hashss && Equal(s[last:], sep) {
-		return last
-	}
-	for i := last - 1; i >= 0; i-- {
-		h *= bytealg.PrimeRK
-		h += uint32(s[i])
-		h -= pow * uint32(s[i+n])
-		if h == hashss && Equal(s[i:i+n], sep) {
-			return i
-		}
-	}
-	return -1
-}
-
-// LastIndexByte returns the index of the last instance of c in s, or -1 if c is not present in s.
-func LastIndexByte(s []byte, c byte) int {
-	for i := len(s) - 1; i >= 0; i-- {
-		if s[i] == c {
-			return i
-		}
-	}
-	return -1
-}
-
-// IndexRune interprets s as a sequence of UTF-8-encoded code points.
-// It returns the byte index of the first occurrence in s of the given rune.
-// It returns -1 if rune is not present in s.
-// If r is utf8.RuneError, it returns the first instance of any
-// invalid UTF-8 byte sequence.
-func IndexRune(s []byte, r rune) int {
-	switch {
-	case 0 <= r && r < utf8.RuneSelf:
-		return IndexByte(s, byte(r))
-	case r == utf8.RuneError:
-		for i := 0; i < len(s); {
-			r1, n := utf8.DecodeRune(s[i:])
-			if r1 == utf8.RuneError {
-				return i
-			}
-			i += n
-		}
-		return -1
-	case !utf8.ValidRune(r):
-		return -1
-	default:
-		var b [utf8.UTFMax]byte
-		n := utf8.EncodeRune(b[:], r)
-		return Index(s, b[:n])
-	}
-}
-
-// IndexAny interprets s as a sequence of UTF-8-encoded Unicode code points.
-// It returns the byte index of the first occurrence in s of any of the Unicode
-// code points in chars. It returns -1 if chars is empty or if there is no code
-// point in common.
-func IndexAny(s []byte, chars string) int {
-	if chars == "" {
-		// Avoid scanning all of s.
-		return -1
-	}
-	if len(s) == 1 {
-		r := rune(s[0])
-		if r >= utf8.RuneSelf {
-			// search utf8.RuneError.
-			for _, r = range chars {
-				if r == utf8.RuneError {
-					return 0
-				}
-			}
-			return -1
-		}
-		if bytealg.IndexByteString(chars, s[0]) >= 0 {
-			return 0
-		}
-		return -1
-	}
-	if len(chars) == 1 {
-		r := rune(chars[0])
-		if r >= utf8.RuneSelf {
-			r = utf8.RuneError
-		}
-		return IndexRune(s, r)
-	}
-	if len(s) > 8 {
-		if as, isASCII := makeASCIISet(chars); isASCII {
-			for i, c := range s {
-				if as.contains(c) {
-					return i
-				}
-			}
-			return -1
-		}
-	}
-	var width int
-	for i := 0; i < len(s); i += width {
-		r := rune(s[i])
-		if r < utf8.RuneSelf {
-			if bytealg.IndexByteString(chars, s[i]) >= 0 {
-				return i
-			}
-			width = 1
-			continue
-		}
-		r, width = utf8.DecodeRune(s[i:])
-		if r != utf8.RuneError {
-			// r is 2 to 4 bytes
-			if len(chars) == width {
-				if chars == string(r) {
-					return i
-				}
-				continue
-			}
-			// Use bytealg.IndexString for performance if available.
-			if bytealg.MaxLen >= width {
-				if bytealg.IndexString(chars, string(r)) >= 0 {
-					return i
-				}
-				continue
-			}
-		}
-		for _, ch := range chars {
-			if r == ch {
-				return i
-			}
-		}
-	}
-	return -1
-}
-
-// LastIndexAny interprets s as a sequence of UTF-8-encoded Unicode code
-// points. It returns the byte index of the last occurrence in s of any of
-// the Unicode code points in chars. It returns -1 if chars is empty or if
-// there is no code point in common.
-func LastIndexAny(s []byte, chars string) int {
-	if chars == "" {
-		// Avoid scanning all of s.
-		return -1
-	}
-	if len(s) > 8 {
-		if as, isASCII := makeASCIISet(chars); isASCII {
-			for i := len(s) - 1; i >= 0; i-- {
-				if as.contains(s[i]) {
-					return i
-				}
-			}
-			return -1
-		}
-	}
-	if len(s) == 1 {
-		r := rune(s[0])
-		if r >= utf8.RuneSelf {
-			for _, r = range chars {
-				if r == utf8.RuneError {
-					return 0
-				}
-			}
-			return -1
-		}
-		if bytealg.IndexByteString(chars, s[0]) >= 0 {
-			return 0
-		}
-		return -1
-	}
-	if len(chars) == 1 {
-		cr := rune(chars[0])
-		if cr >= utf8.RuneSelf {
-			cr = utf8.RuneError
-		}
-		for i := len(s); i > 0; {
-			r, size := utf8.DecodeLastRune(s[:i])
-			i -= size
-			if r == cr {
-				return i
-			}
-		}
-		return -1
-	}
-	for i := len(s); i > 0; {
-		r := rune(s[i-1])
-		if r < utf8.RuneSelf {
-			if bytealg.IndexByteString(chars, s[i-1]) >= 0 {
-				return i - 1
-			}
-			i--
-			continue
-		}
-		r, size := utf8.DecodeLastRune(s[:i])
-		i -= size
-		if r != utf8.RuneError {
-			// r is 2 to 4 bytes
-			if len(chars) == size {
-				if chars == string(r) {
-					return i
-				}
-				continue
-			}
-			// Use bytealg.IndexString for performance if available.
-			if bytealg.MaxLen >= size {
-				if bytealg.IndexString(chars, string(r)) >= 0 {
-					return i
-				}
-				continue
-			}
-		}
-		for _, ch := range chars {
-			if r == ch {
-				return i
-			}
-		}
-	}
-	return -1
-}
-
-// Generic split: splits after each instance of sep,
-// including sepSave bytes of sep in the subslices.
-func genSplit(s, sep []byte, sepSave, n int) [][]byte {
-	if n == 0 {
-		return nil
-	}
-	if len(sep) == 0 {
-		return explode(s, n)
-	}
-	if n < 0 {
-		n = Count(s, sep) + 1
-	}
-
-	a := make([][]byte, n)
-	n--
-	i := 0
-	for i < n {
-		m := Index(s, sep)
-		if m < 0 {
-			break
-		}
-		a[i] = s[: m+sepSave : m+sepSave]
-		s = s[m+len(sep):]
-		i++
-	}
-	a[i] = s
-	return a[:i+1]
-}
-
-// SplitN slices s into subslices separated by sep and returns a slice of
-// the subslices between those separators.
-// If sep is empty, SplitN splits after each UTF-8 sequence.
-// The count determines the number of subslices to return:
-//   n > 0: at most n subslices; the last subslice will be the unsplit remainder.
-//   n == 0: the result is nil (zero subslices)
-//   n < 0: all subslices
-//
-// To split around the first instance of a separator, see Cut.
-func SplitN(s, sep []byte, n int) [][]byte { return genSplit(s, sep, 0, n) }
-
-// SplitAfterN slices s into subslices after each instance of sep and
-// returns a slice of those subslices.
-// If sep is empty, SplitAfterN splits after each UTF-8 sequence.
-// The count determines the number of subslices to return:
-//   n > 0: at most n subslices; the last subslice will be the unsplit remainder.
-//   n == 0: the result is nil (zero subslices)
-//   n < 0: all subslices
-func SplitAfterN(s, sep []byte, n int) [][]byte {
-	return genSplit(s, sep, len(sep), n)
-}
-
-// Split slices s into all subslices separated by sep and returns a slice of
-// the subslices between those separators.
-// If sep is empty, Split splits after each UTF-8 sequence.
-// It is equivalent to SplitN with a count of -1.
-//
-// To split around the first instance of a separator, see Cut.
-func Split(s, sep []byte) [][]byte { return genSplit(s, sep, 0, -1) }
-
-// SplitAfter slices s into all subslices after each instance of sep and
-// returns a slice of those subslices.
-// If sep is empty, SplitAfter splits after each UTF-8 sequence.
-// It is equivalent to SplitAfterN with a count of -1.
-func SplitAfter(s, sep []byte) [][]byte {
-	return genSplit(s, sep, len(sep), -1)
-}
-
-var asciiSpace = [256]uint8{'\t': 1, '\n': 1, '\v': 1, '\f': 1, '\r': 1, ' ': 1}
-
-// Fields interprets s as a sequence of UTF-8-encoded code points.
-// It splits the slice s around each instance of one or more consecutive white space
-// characters, as defined by unicode.IsSpace, returning a slice of subslices of s or an
-// empty slice if s contains only white space.
-func Fields(s []byte) [][]byte {
-	// First count the fields.
-	// This is an exact count if s is ASCII, otherwise it is an approximation.
-	n := 0
-	wasSpace := 1
-	// setBits is used to track which bits are set in the bytes of s.
-	setBits := uint8(0)
-	for i := 0; i < len(s); i++ {
-		r := s[i]
-		setBits |= r
-		isSpace := int(asciiSpace[r])
-		n += wasSpace & ^isSpace
-		wasSpace = isSpace
-	}
-
-	if setBits >= utf8.RuneSelf {
-		// Some runes in the input slice are not ASCII.
-		return FieldsFunc(s, unicode.IsSpace)
-	}
-
-	// ASCII fast path
-	a := make([][]byte, n)
-	na := 0
-	fieldStart := 0
-	i := 0
-	// Skip spaces in the front of the input.
-	for i < len(s) && asciiSpace[s[i]] != 0 {
-		i++
-	}
-	fieldStart = i
-	for i < len(s) {
-		if asciiSpace[s[i]] == 0 {
-			i++
-			continue
-		}
-		a[na] = s[fieldStart:i:i]
-		na++
-		i++
-		// Skip spaces in between fields.
-		for i < len(s) && asciiSpace[s[i]] != 0 {
-			i++
-		}
-		fieldStart = i
-	}
-	if fieldStart < len(s) { // Last field might end at EOF.
-		a[na] = s[fieldStart:len(s):len(s)]
-	}
-	return a
-}
-
-// FieldsFunc interprets s as a sequence of UTF-8-encoded code points.
-// It splits the slice s at each run of code points c satisfying f(c) and
-// returns a slice of subslices of s. If all code points in s satisfy f(c), or
-// len(s) == 0, an empty slice is returned.
-//
-// FieldsFunc makes no guarantees about the order in which it calls f(c)
-// and assumes that f always returns the same value for a given c.
-func FieldsFunc(s []byte, f func(rune) bool) [][]byte {
-	// A span is used to record a slice of s of the form s[start:end].
-	// The start index is inclusive and the end index is exclusive.
-	type span struct {
-		start int
-		end   int
-	}
-	spans := make([]span, 0, 32)
-
-	// Find the field start and end indices.
-	// Doing this in a separate pass (rather than slicing the string s
-	// and collecting the result substrings right away) is significantly
-	// more efficient, possibly due to cache effects.
-	start := -1 // valid span start if >= 0
-	for i := 0; i < len(s); {
-		size := 1
-		r := rune(s[i])
-		if r >= utf8.RuneSelf {
-			r, size = utf8.DecodeRune(s[i:])
-		}
-		if f(r) {
-			if start >= 0 {
-				spans = append(spans, span{start, i})
-				start = -1
-			}
-		} else {
-			if start < 0 {
-				start = i
-			}
-		}
-		i += size
-	}
-
-	// Last field might end at EOF.
-	if start >= 0 {
-		spans = append(spans, span{start, len(s)})
-	}
-
-	// Create subslices from recorded field indices.
-	a := make([][]byte, len(spans))
-	for i, span := range spans {
-		a[i] = s[span.start:span.end:span.end]
-	}
-
-	return a
-}
-
-// Join concatenates the elements of s to create a new byte slice. The separator
-// sep is placed between elements in the resulting slice.
-func Join(s [][]byte, sep []byte) []byte {
-	if len(s) == 0 {
-		return []byte{}
-	}
-	if len(s) == 1 {
-		// Just return a copy.
-		return append([]byte(nil), s[0]...)
-	}
-	n := len(sep) * (len(s) - 1)
-	for _, v := range s {
-		n += len(v)
-	}
-
-	b := make([]byte, n)
-	bp := copy(b, s[0])
-	for _, v := range s[1:] {
-		bp += copy(b[bp:], sep)
-		bp += copy(b[bp:], v)
-	}
-	return b
-}
-
-// HasPrefix tests whether the byte slice s begins with prefix.
-func HasPrefix(s, prefix []byte) bool {
-	return len(s) >= len(prefix) && Equal(s[0:len(prefix)], prefix)
-}
-
-// HasSuffix tests whether the byte slice s ends with suffix.
-func HasSuffix(s, suffix []byte) bool {
-	return len(s) >= len(suffix) && Equal(s[len(s)-len(suffix):], suffix)
-}
-
-// Map returns a copy of the byte slice s with all its characters modified
-// according to the mapping function. If mapping returns a negative value, the character is
-// dropped from the byte slice with no replacement. The characters in s and the
-// output are interpreted as UTF-8-encoded code points.
-func Map(mapping func(r rune) rune, s []byte) []byte {
-	// In the worst case, the slice can grow when mapped, making
-	// things unpleasant. But it's so rare we barge in assuming it's
-	// fine. It could also shrink but that falls out naturally.
-	maxbytes := len(s) // length of b
-	nbytes := 0        // number of bytes encoded in b
-	b := make([]byte, maxbytes)
-	for i := 0; i < len(s); {
-		wid := 1
-		r := rune(s[i])
-		if r >= utf8.RuneSelf {
-			r, wid = utf8.DecodeRune(s[i:])
-		}
-		r = mapping(r)
-		if r >= 0 {
-			rl := utf8.RuneLen(r)
-			if rl < 0 {
-				rl = len(string(utf8.RuneError))
-			}
-			if nbytes+rl > maxbytes {
-				// Grow the buffer.
-				maxbytes = maxbytes*2 + utf8.UTFMax
-				nb := make([]byte, maxbytes)
-				copy(nb, b[0:nbytes])
-				b = nb
-			}
-			nbytes += utf8.EncodeRune(b[nbytes:maxbytes], r)
-		}
-		i += wid
-	}
-	return b[0:nbytes]
-}
-
-// Repeat returns a new byte slice consisting of count copies of b.
-//
-// It panics if count is negative or if
-// the result of (len(b) * count) overflows.
-func Repeat(b []byte, count int) []byte {
-	if count == 0 {
-		return []byte{}
-	}
-	// Since we cannot return an error on overflow,
-	// we should panic if the repeat will generate
-	// an overflow.
-	// See Issue golang.org/issue/16237.
-	if count < 0 {
-		panic("bytes: negative Repeat count")
-	} else if len(b)*count/count != len(b) {
-		panic("bytes: Repeat count causes overflow")
-	}
-
-	nb := make([]byte, len(b)*count)
-	bp := copy(nb, b)
-	for bp < len(nb) {
-		copy(nb[bp:], nb[:bp])
-		bp *= 2
-	}
-	return nb
-}
-
-// ToUpper returns a copy of the byte slice s with all Unicode letters mapped to
-// their upper case.
-func ToUpper(s []byte) []byte {
-	isASCII, hasLower := true, false
-	for i := 0; i < len(s); i++ {
-		c := s[i]
-		if c >= utf8.RuneSelf {
-			isASCII = false
-			break
-		}
-		hasLower = hasLower || ('a' <= c && c <= 'z')
-	}
-
-	if isASCII { // optimize for ASCII-only byte slices.
-		if !hasLower {
-			// Just return a copy.
-			return append([]byte(""), s...)
-		}
-		b := make([]byte, len(s))
-		for i := 0; i < len(s); i++ {
-			c := s[i]
-			if 'a' <= c && c <= 'z' {
-				c -= 'a' - 'A'
-			}
-			b[i] = c
-		}
-		return b
-	}
-	return Map(unicode.ToUpper, s)
-}
-
-// ToLower returns a copy of the byte slice s with all Unicode letters mapped to
-// their lower case.
-func ToLower(s []byte) []byte {
-	isASCII, hasUpper := true, false
-	for i := 0; i < len(s); i++ {
-		c := s[i]
-		if c >= utf8.RuneSelf {
-			isASCII = false
-			break
-		}
-		hasUpper = hasUpper || ('A' <= c && c <= 'Z')
-	}
-
-	if isASCII { // optimize for ASCII-only byte slices.
-		if !hasUpper {
-			return append([]byte(""), s...)
-		}
-		b := make([]byte, len(s))
-		for i := 0; i < len(s); i++ {
-			c := s[i]
-			if 'A' <= c && c <= 'Z' {
-				c += 'a' - 'A'
-			}
-			b[i] = c
-		}
-		return b
-	}
-	return Map(unicode.ToLower, s)
-}
-
-// ToTitle treats s as UTF-8-encoded bytes and returns a copy with all the Unicode letters mapped to their title case.
-func ToTitle(s []byte) []byte { return Map(unicode.ToTitle, s) }
-
-// ToUpperSpecial treats s as UTF-8-encoded bytes and returns a copy with all the Unicode letters mapped to their
-// upper case, giving priority to the special casing rules.
-func ToUpperSpecial(c unicode.SpecialCase, s []byte) []byte {
-	return Map(c.ToUpper, s)
-}
-
-// ToLowerSpecial treats s as UTF-8-encoded bytes and returns a copy with all the Unicode letters mapped to their
-// lower case, giving priority to the special casing rules.
-func ToLowerSpecial(c unicode.SpecialCase, s []byte) []byte {
-	return Map(c.ToLower, s)
-}
-
-// ToTitleSpecial treats s as UTF-8-encoded bytes and returns a copy with all the Unicode letters mapped to their
-// title case, giving priority to the special casing rules.
-func ToTitleSpecial(c unicode.SpecialCase, s []byte) []byte {
-	return Map(c.ToTitle, s)
-}
-
-// ToValidUTF8 treats s as UTF-8-encoded bytes and returns a copy with each run of bytes
-// representing invalid UTF-8 replaced with the bytes in replacement, which may be empty.
-func ToValidUTF8(s, replacement []byte) []byte {
-	b := make([]byte, 0, len(s)+len(replacement))
-	invalid := false // previous byte was from an invalid UTF-8 sequence
-	for i := 0; i < len(s); {
-		c := s[i]
-		if c < utf8.RuneSelf {
-			i++
-			invalid = false
-			b = append(b, c)
-			continue
-		}
-		_, wid := utf8.DecodeRune(s[i:])
-		if wid == 1 {
-			i++
-			if !invalid {
-				invalid = true
-				b = append(b, replacement...)
-			}
-			continue
-		}
-		invalid = false
-		b = append(b, s[i:i+wid]...)
-		i += wid
-	}
-	return b
-}
-
-// isSeparator reports whether the rune could mark a word boundary.
-// TODO: update when package unicode captures more of the properties.
-func isSeparator(r rune) bool {
-	// ASCII alphanumerics and underscore are not separators
-	if r <= 0x7F {
-		switch {
-		case '0' <= r && r <= '9':
-			return false
-		case 'a' <= r && r <= 'z':
-			return false
-		case 'A' <= r && r <= 'Z':
-			return false
-		case r == '_':
-			return false
-		}
-		return true
-	}
-	// Letters and digits are not separators
-	if unicode.IsLetter(r) || unicode.IsDigit(r) {
-		return false
-	}
-	// Otherwise, all we can do for now is treat spaces as separators.
-	return unicode.IsSpace(r)
-}
-
-// Title treats s as UTF-8-encoded bytes and returns a copy with all Unicode letters that begin
-// words mapped to their title case.
-//
-// Deprecated: The rule Title uses for word boundaries does not handle Unicode
-// punctuation properly. Use golang.org/x/text/cases instead.
-func Title(s []byte) []byte {
-	// Use a closure here to remember state.
-	// Hackish but effective. Depends on Map scanning in order and calling
-	// the closure once per rune.
-	prev := ' '
-	return Map(
-		func(r rune) rune {
-			if isSeparator(prev) {
-				prev = r
-				return unicode.ToTitle(r)
-			}
-			prev = r
-			return r
-		},
-		s)
-}
-
-// TrimLeftFunc treats s as UTF-8-encoded bytes and returns a subslice of s by slicing off
-// all leading UTF-8-encoded code points c that satisfy f(c).
-func TrimLeftFunc(s []byte, f func(r rune) bool) []byte {
-	i := indexFunc(s, f, false)
-	if i == -1 {
-		return nil
-	}
-	return s[i:]
-}
-
-// TrimRightFunc returns a subslice of s by slicing off all trailing
-// UTF-8-encoded code points c that satisfy f(c).
-func TrimRightFunc(s []byte, f func(r rune) bool) []byte {
-	i := lastIndexFunc(s, f, false)
-	if i >= 0 && s[i] >= utf8.RuneSelf {
-		_, wid := utf8.DecodeRune(s[i:])
-		i += wid
-	} else {
-		i++
-	}
-	return s[0:i]
-}
-
-// TrimFunc returns a subslice of s by slicing off all leading and trailing
-// UTF-8-encoded code points c that satisfy f(c).
-func TrimFunc(s []byte, f func(r rune) bool) []byte {
-	return TrimRightFunc(TrimLeftFunc(s, f), f)
-}
-
-// TrimPrefix returns s without the provided leading prefix string.
-// If s doesn't start with prefix, s is returned unchanged.
-func TrimPrefix(s, prefix []byte) []byte {
-	if HasPrefix(s, prefix) {
-		return s[len(prefix):]
-	}
-	return s
-}
-
-// TrimSuffix returns s without the provided trailing suffix string.
-// If s doesn't end with suffix, s is returned unchanged.
-func TrimSuffix(s, suffix []byte) []byte {
-	if HasSuffix(s, suffix) {
-		return s[:len(s)-len(suffix)]
-	}
-	return s
-}
-
-// IndexFunc interprets s as a sequence of UTF-8-encoded code points.
-// It returns the byte index in s of the first Unicode
-// code point satisfying f(c), or -1 if none do.
-func IndexFunc(s []byte, f func(r rune) bool) int {
-	return indexFunc(s, f, true)
-}
-
-// LastIndexFunc interprets s as a sequence of UTF-8-encoded code points.
-// It returns the byte index in s of the last Unicode
-// code point satisfying f(c), or -1 if none do.
-func LastIndexFunc(s []byte, f func(r rune) bool) int {
-	return lastIndexFunc(s, f, true)
-}
-
-// indexFunc is the same as IndexFunc except that if
-// truth==false, the sense of the predicate function is
-// inverted.
-func indexFunc(s []byte, f func(r rune) bool, truth bool) int {
-	start := 0
-	for start < len(s) {
-		wid := 1
-		r := rune(s[start])
-		if r >= utf8.RuneSelf {
-			r, wid = utf8.DecodeRune(s[start:])
-		}
-		if f(r) == truth {
-			return start
-		}
-		start += wid
-	}
-	return -1
-}
-
-// lastIndexFunc is the same as LastIndexFunc except that if
-// truth==false, the sense of the predicate function is
-// inverted.
-func lastIndexFunc(s []byte, f func(r rune) bool, truth bool) int {
-	for i := len(s); i > 0; {
-		r, size := rune(s[i-1]), 1
-		if r >= utf8.RuneSelf {
-			r, size = utf8.DecodeLastRune(s[0:i])
-		}
-		i -= size
-		if f(r) == truth {
-			return i
-		}
-	}
-	return -1
-}
-
-// asciiSet is a 32-byte value, where each bit represents the presence of a
-// given ASCII character in the set. The 128-bits of the lower 16 bytes,
-// starting with the least-significant bit of the lowest word to the
-// most-significant bit of the highest word, map to the full range of all
-// 128 ASCII characters. The 128-bits of the upper 16 bytes will be zeroed,
-// ensuring that any non-ASCII character will be reported as not in the set.
-// This allocates a total of 32 bytes even though the upper half
-// is unused to avoid bounds checks in asciiSet.contains.
-type asciiSet [8]uint32
-
-// makeASCIISet creates a set of ASCII characters and reports whether all
-// characters in chars are ASCII.
-func makeASCIISet(chars string) (as asciiSet, ok bool) {
-	for i := 0; i < len(chars); i++ {
-		c := chars[i]
-		if c >= utf8.RuneSelf {
-			return as, false
-		}
-		as[c/32] |= 1 << (c % 32)
-	}
-	return as, true
-}
-
-// contains reports whether c is inside the set.
-func (as *asciiSet) contains(c byte) bool {
-	return (as[c/32] & (1 << (c % 32))) != 0
-}
-
-// containsRune is a simplified version of strings.ContainsRune
-// to avoid importing the strings package.
-// We avoid bytes.ContainsRune to avoid allocating a temporary copy of s.
-func containsRune(s string, r rune) bool {
-	for _, c := range s {
-		if c == r {
-			return true
-		}
-	}
-	return false
-}
-
-// Trim returns a subslice of s by slicing off all leading and
-// trailing UTF-8-encoded code points contained in cutset.
-func Trim(s []byte, cutset string) []byte {
-	if len(s) == 0 {
-		// This is what we've historically done.
-		return nil
-	}
-	if cutset == "" {
-		return s
-	}
-	if len(cutset) == 1 && cutset[0] < utf8.RuneSelf {
-		return trimLeftByte(trimRightByte(s, cutset[0]), cutset[0])
-	}
-	if as, ok := makeASCIISet(cutset); ok {
-		return trimLeftASCII(trimRightASCII(s, &as), &as)
-	}
-	return trimLeftUnicode(trimRightUnicode(s, cutset), cutset)
-}
-
-// TrimLeft returns a subslice of s by slicing off all leading
-// UTF-8-encoded code points contained in cutset.
-func TrimLeft(s []byte, cutset string) []byte {
-	if len(s) == 0 {
-		// This is what we've historically done.
-		return nil
-	}
-	if cutset == "" {
-		return s
-	}
-	if len(cutset) == 1 && cutset[0] < utf8.RuneSelf {
-		return trimLeftByte(s, cutset[0])
-	}
-	if as, ok := makeASCIISet(cutset); ok {
-		return trimLeftASCII(s, &as)
-	}
-	return trimLeftUnicode(s, cutset)
-}
-
-func trimLeftByte(s []byte, c byte) []byte {
-	for len(s) > 0 && s[0] == c {
-		s = s[1:]
-	}
-	if len(s) == 0 {
-		// This is what we've historically done.
-		return nil
-	}
-	return s
-}
-
-func trimLeftASCII(s []byte, as *asciiSet) []byte {
-	for len(s) > 0 {
-		if !as.contains(s[0]) {
-			break
-		}
-		s = s[1:]
-	}
-	if len(s) == 0 {
-		// This is what we've historically done.
-		return nil
-	}
-	return s
-}
-
-func trimLeftUnicode(s []byte, cutset string) []byte {
-	for len(s) > 0 {
-		r, n := rune(s[0]), 1
-		if r >= utf8.RuneSelf {
-			r, n = utf8.DecodeRune(s)
-		}
-		if !containsRune(cutset, r) {
-			break
-		}
-		s = s[n:]
-	}
-	if len(s) == 0 {
-		// This is what we've historically done.
-		return nil
-	}
-	return s
-}
-
-// TrimRight returns a subslice of s by slicing off all trailing
-// UTF-8-encoded code points that are contained in cutset.
-func TrimRight(s []byte, cutset string) []byte {
-	if len(s) == 0 || cutset == "" {
-		return s
-	}
-	if len(cutset) == 1 && cutset[0] < utf8.RuneSelf {
-		return trimRightByte(s, cutset[0])
-	}
-	if as, ok := makeASCIISet(cutset); ok {
-		return trimRightASCII(s, &as)
-	}
-	return trimRightUnicode(s, cutset)
-}
-
-func trimRightByte(s []byte, c byte) []byte {
-	for len(s) > 0 && s[len(s)-1] == c {
-		s = s[:len(s)-1]
-	}
-	return s
-}
-
-func trimRightASCII(s []byte, as *asciiSet) []byte {
-	for len(s) > 0 {
-		if !as.contains(s[len(s)-1]) {
-			break
-		}
-		s = s[:len(s)-1]
-	}
-	return s
-}
-
-func trimRightUnicode(s []byte, cutset string) []byte {
-	for len(s) > 0 {
-		r, n := rune(s[len(s)-1]), 1
-		if r >= utf8.RuneSelf {
-			r, n = utf8.DecodeLastRune(s)
-		}
-		if !containsRune(cutset, r) {
-			break
-		}
-		s = s[:len(s)-n]
-	}
-	return s
-}
-
-// TrimSpace returns a subslice of s by slicing off all leading and
-// trailing white space, as defined by Unicode.
-func TrimSpace(s []byte) []byte {
-	// Fast path for ASCII: look for the first ASCII non-space byte
-	start := 0
-	for ; start < len(s); start++ {
-		c := s[start]
-		if c >= utf8.RuneSelf {
-			// If we run into a non-ASCII byte, fall back to the
-			// slower unicode-aware method on the remaining bytes
-			return TrimFunc(s[start:], unicode.IsSpace)
-		}
-		if asciiSpace[c] == 0 {
-			break
-		}
-	}
-
-	// Now look for the first ASCII non-space byte from the end
-	stop := len(s)
-	for ; stop > start; stop-- {
-		c := s[stop-1]
-		if c >= utf8.RuneSelf {
-			return TrimFunc(s[start:stop], unicode.IsSpace)
-		}
-		if asciiSpace[c] == 0 {
-			break
-		}
-	}
-
-	// At this point s[start:stop] starts and ends with an ASCII
-	// non-space bytes, so we're done. Non-ASCII cases have already
-	// been handled above.
-	if start == stop {
-		// Special case to preserve previous TrimLeftFunc behavior,
-		// returning nil instead of empty slice if all spaces.
-		return nil
-	}
-	return s[start:stop]
-}
-
-// Runes interprets s as a sequence of UTF-8-encoded code points.
-// It returns a slice of runes (Unicode code points) equivalent to s.
-func Runes(s []byte) []rune {
-	t := make([]rune, utf8.RuneCount(s))
-	i := 0
-	for len(s) > 0 {
-		r, l := utf8.DecodeRune(s)
-		t[i] = r
-		i++
-		s = s[l:]
-	}
-	return t
-}
-
-// Replace returns a copy of the slice s with the first n
-// non-overlapping instances of old replaced by new.
-// If old is empty, it matches at the beginning of the slice
-// and after each UTF-8 sequence, yielding up to k+1 replacements
-// for a k-rune slice.
-// If n < 0, there is no limit on the number of replacements.
-func Replace(s, old, new []byte, n int) []byte {
-	m := 0
-	if n != 0 {
-		// Compute number of replacements.
-		m = Count(s, old)
-	}
-	if m == 0 {
-		// Just return a copy.
-		return append([]byte(nil), s...)
-	}
-	if n < 0 || m < n {
-		n = m
-	}
-
-	// Apply replacements to buffer.
-	t := make([]byte, len(s)+n*(len(new)-len(old)))
-	w := 0
-	start := 0
-	for i := 0; i < n; i++ {
-		j := start
-		if len(old) == 0 {
-			if i > 0 {
-				_, wid := utf8.DecodeRune(s[start:])
-				j += wid
-			}
-		} else {
-			j += Index(s[start:], old)
-		}
-		w += copy(t[w:], s[start:j])
-		w += copy(t[w:], new)
-		start = j + len(old)
-	}
-	w += copy(t[w:], s[start:])
-	return t[0:w]
-}
-
-// ReplaceAll returns a copy of the slice s with all
-// non-overlapping instances of old replaced by new.
-// If old is empty, it matches at the beginning of the slice
-// and after each UTF-8 sequence, yielding up to k+1 replacements
-// for a k-rune slice.
-func ReplaceAll(s, old, new []byte) []byte {
-	return Replace(s, old, new, -1)
-}
-
-// EqualFold reports whether s and t, interpreted as UTF-8 strings,
-// are equal under Unicode case-folding, which is a more general
-// form of case-insensitivity.
-func EqualFold(s, t []byte) bool {
-	for len(s) != 0 && len(t) != 0 {
-		// Extract first rune from each.
-		var sr, tr rune
-		if s[0] < utf8.RuneSelf {
-			sr, s = rune(s[0]), s[1:]
-		} else {
-			r, size := utf8.DecodeRune(s)
-			sr, s = r, s[size:]
-		}
-		if t[0] < utf8.RuneSelf {
-			tr, t = rune(t[0]), t[1:]
-		} else {
-			r, size := utf8.DecodeRune(t)
-			tr, t = r, t[size:]
-		}
-
-		// If they match, keep going; if not, return false.
-
-		// Easy case.
-		if tr == sr {
-			continue
-		}
-
-		// Make sr < tr to simplify what follows.
-		if tr < sr {
-			tr, sr = sr, tr
-		}
-		// Fast check for ASCII.
-		if tr < utf8.RuneSelf {
-			// ASCII only, sr/tr must be upper/lower case
-			if 'A' <= sr && sr <= 'Z' && tr == sr+'a'-'A' {
-				continue
-			}
-			return false
-		}
-
-		// General case. SimpleFold(x) returns the next equivalent rune > x
-		// or wraps around to smaller values.
-		r := unicode.SimpleFold(sr)
-		for r != sr && r < tr {
-			r = unicode.SimpleFold(r)
-		}
-		if r == tr {
-			continue
-		}
-		return false
-	}
-
-	// One string is empty. Are both?
-	return len(s) == len(t)
-}
-
-// Index returns the index of the first instance of sep in s, or -1 if sep is not present in s.
-func Index(s, sep []byte) int {
-	n := len(sep)
-	switch {
-	case n == 0:
-		return 0
-	case n == 1:
-		return IndexByte(s, sep[0])
-	case n == len(s):
-		if Equal(sep, s) {
-			return 0
-		}
-		return -1
-	case n > len(s):
-		return -1
-	case n <= bytealg.MaxLen:
-		// Use brute force when s and sep both are small
-		if len(s) <= bytealg.MaxBruteForce {
-			return bytealg.Index(s, sep)
-		}
-		c0 := sep[0]
-		c1 := sep[1]
-		i := 0
-		t := len(s) - n + 1
-		fails := 0
-		for i < t {
-			if s[i] != c0 {
-				// IndexByte is faster than bytealg.Index, so use it as long as
-				// we're not getting lots of false positives.
-				o := IndexByte(s[i+1:t], c0)
-				if o < 0 {
-					return -1
-				}
-				i += o + 1
-			}
-			if s[i+1] == c1 && Equal(s[i:i+n], sep) {
-				return i
-			}
-			fails++
-			i++
-			// Switch to bytealg.Index when IndexByte produces too many false positives.
-			if fails > bytealg.Cutover(i) {
-				r := bytealg.Index(s[i:], sep)
-				if r >= 0 {
-					return r + i
-				}
-				return -1
-			}
-		}
-		return -1
-	}
-	c0 := sep[0]
-	c1 := sep[1]
-	i := 0
-	fails := 0
-	t := len(s) - n + 1
-	for i < t {
-		if s[i] != c0 {
-			o := IndexByte(s[i+1:t], c0)
-			if o < 0 {
-				break
-			}
-			i += o + 1
-		}
-		if s[i+1] == c1 && Equal(s[i:i+n], sep) {
-			return i
-		}
-		i++
-		fails++
-		if fails >= 4+i>>4 && i < t {
-			// Give up on IndexByte, it isn't skipping ahead
-			// far enough to be better than Rabin-Karp.
-			// Experiments (using IndexPeriodic) suggest
-			// the cutover is about 16 byte skips.
-			// TODO: if large prefixes of sep are matching
-			// we should cutover at even larger average skips,
-			// because Equal becomes that much more expensive.
-			// This code does not take that effect into account.
-			j := bytealg.IndexRabinKarpBytes(s[i:], sep)
-			if j < 0 {
-				return -1
-			}
-			return i + j
-		}
-	}
-	return -1
-}
-
-// Cut slices s around the first instance of sep,
-// returning the text before and after sep.
-// The found result reports whether sep appears in s.
-// If sep does not appear in s, cut returns s, nil, false.
-//
-// Cut returns slices of the original slice s, not copies.
-func Cut(s, sep []byte) (before, after []byte, found bool) {
-	if i := Index(s, sep); i >= 0 {
-		return s[:i], s[i+len(sep):], true
-	}
-	return s, nil, false
-}
diff --git a/contrib/go/_std_1.18/src/bytes/reader.go b/contrib/go/_std_1.18/src/bytes/reader.go
deleted file mode 100644
index 5946cf9780..0000000000
--- a/contrib/go/_std_1.18/src/bytes/reader.go
+++ /dev/null
@@ -1,160 +0,0 @@
-// Copyright 2012 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package bytes
-
-import (
-	"errors"
-	"io"
-	"unicode/utf8"
-)
-
-// A Reader implements the io.Reader, io.ReaderAt, io.WriterTo, io.Seeker,
-// io.ByteScanner, and io.RuneScanner interfaces by reading from
-// a byte slice.
-// Unlike a Buffer, a Reader is read-only and supports seeking.
-// The zero value for Reader operates like a Reader of an empty slice.
-type Reader struct {
-	s        []byte
-	i        int64 // current reading index
-	prevRune int   // index of previous rune; or < 0
-}
-
-// Len returns the number of bytes of the unread portion of the
-// slice.
-func (r *Reader) Len() int {
-	if r.i >= int64(len(r.s)) {
-		return 0
-	}
-	return int(int64(len(r.s)) - r.i)
-}
-
-// Size returns the original length of the underlying byte slice.
-// Size is the number of bytes available for reading via ReadAt.
-// The returned value is always the same and is not affected by calls
-// to any other method.
-func (r *Reader) Size() int64 { return int64(len(r.s)) }
-
-// Read implements the io.Reader interface.
-func (r *Reader) Read(b []byte) (n int, err error) {
-	if r.i >= int64(len(r.s)) {
-		return 0, io.EOF
-	}
-	r.prevRune = -1
-	n = copy(b, r.s[r.i:])
-	r.i += int64(n)
-	return
-}
-
-// ReadAt implements the io.ReaderAt interface.
-func (r *Reader) ReadAt(b []byte, off int64) (n int, err error) {
-	// cannot modify state - see io.ReaderAt
-	if off < 0 {
-		return 0, errors.New("bytes.Reader.ReadAt: negative offset")
-	}
-	if off >= int64(len(r.s)) {
-		return 0, io.EOF
-	}
-	n = copy(b, r.s[off:])
-	if n < len(b) {
-		err = io.EOF
-	}
-	return
-}
-
-// ReadByte implements the io.ByteReader interface.
-func (r *Reader) ReadByte() (byte, error) {
-	r.prevRune = -1
-	if r.i >= int64(len(r.s)) {
-		return 0, io.EOF
-	}
-	b := r.s[r.i]
-	r.i++
-	return b, nil
-}
-
-// UnreadByte complements ReadByte in implementing the io.ByteScanner interface.
-func (r *Reader) UnreadByte() error {
-	if r.i <= 0 {
-		return errors.New("bytes.Reader.UnreadByte: at beginning of slice")
-	}
-	r.prevRune = -1
-	r.i--
-	return nil
-}
-
-// ReadRune implements the io.RuneReader interface.
-func (r *Reader) ReadRune() (ch rune, size int, err error) {
-	if r.i >= int64(len(r.s)) {
-		r.prevRune = -1
-		return 0, 0, io.EOF
-	}
-	r.prevRune = int(r.i)
-	if c := r.s[r.i]; c < utf8.RuneSelf {
-		r.i++
-		return rune(c), 1, nil
-	}
-	ch, size = utf8.DecodeRune(r.s[r.i:])
-	r.i += int64(size)
-	return
-}
-
-// UnreadRune complements ReadRune in implementing the io.RuneScanner interface.
-func (r *Reader) UnreadRune() error {
-	if r.i <= 0 {
-		return errors.New("bytes.Reader.UnreadRune: at beginning of slice")
-	}
-	if r.prevRune < 0 {
-		return errors.New("bytes.Reader.UnreadRune: previous operation was not ReadRune")
-	}
-	r.i = int64(r.prevRune)
-	r.prevRune = -1
-	return nil
-}
-
-// Seek implements the io.Seeker interface.
-func (r *Reader) Seek(offset int64, whence int) (int64, error) {
-	r.prevRune = -1
-	var abs int64
-	switch whence {
-	case io.SeekStart:
-		abs = offset
-	case io.SeekCurrent:
-		abs = r.i + offset
-	case io.SeekEnd:
-		abs = int64(len(r.s)) + offset
-	default:
-		return 0, errors.New("bytes.Reader.Seek: invalid whence")
-	}
-	if abs < 0 {
-		return 0, errors.New("bytes.Reader.Seek: negative position")
-	}
-	r.i = abs
-	return abs, nil
-}
-
-// WriteTo implements the io.WriterTo interface.
-func (r *Reader) WriteTo(w io.Writer) (n int64, err error) {
-	r.prevRune = -1
-	if r.i >= int64(len(r.s)) {
-		return 0, nil
-	}
-	b := r.s[r.i:]
-	m, err := w.Write(b)
-	if m > len(b) {
-		panic("bytes.Reader.WriteTo: invalid Write count")
-	}
-	r.i += int64(m)
-	n = int64(m)
-	if m != len(b) && err == nil {
-		err = io.ErrShortWrite
-	}
-	return
-}
-
-// Reset resets the Reader to be reading from b.
-func (r *Reader) Reset(b []byte) { *r = Reader{b, 0, -1} }
-
-// NewReader returns a new Reader reading from b.
-func NewReader(b []byte) *Reader { return &Reader{b, 0, -1} }
diff --git a/contrib/go/_std_1.18/src/compress/flate/deflate.go b/contrib/go/_std_1.18/src/compress/flate/deflate.go
deleted file mode 100644
index 550032176d..0000000000
--- a/contrib/go/_std_1.18/src/compress/flate/deflate.go
+++ /dev/null
@@ -1,748 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package flate
-
-import (
-	"fmt"
-	"io"
-	"math"
-)
-
-const (
-	NoCompression      = 0
-	BestSpeed          = 1
-	BestCompression    = 9
-	DefaultCompression = -1
-
-	// HuffmanOnly disables Lempel-Ziv match searching and only performs Huffman
-	// entropy encoding. This mode is useful in compressing data that has
-	// already been compressed with an LZ style algorithm (e.g. Snappy or LZ4)
-	// that lacks an entropy encoder. Compression gains are achieved when
-	// certain bytes in the input stream occur more frequently than others.
-	//
-	// Note that HuffmanOnly produces a compressed output that is
-	// RFC 1951 compliant. That is, any valid DEFLATE decompressor will
-	// continue to be able to decompress this output.
-	HuffmanOnly = -2
-)
-
-const (
-	logWindowSize = 15
-	windowSize    = 1 << logWindowSize
-	windowMask    = windowSize - 1
-
-	// The LZ77 step produces a sequence of literal tokens and <length, offset>
-	// pair tokens. The offset is also known as distance. The underlying wire
-	// format limits the range of lengths and offsets. For example, there are
-	// 256 legitimate lengths: those in the range [3, 258]. This package's
-	// compressor uses a higher minimum match length, enabling optimizations
-	// such as finding matches via 32-bit loads and compares.
-	baseMatchLength = 3       // The smallest match length per the RFC section 3.2.5
-	minMatchLength  = 4       // The smallest match length that the compressor actually emits
-	maxMatchLength  = 258     // The largest match length
-	baseMatchOffset = 1       // The smallest match offset
-	maxMatchOffset  = 1 << 15 // The largest match offset
-
-	// The maximum number of tokens we put into a single flate block, just to
-	// stop things from getting too large.
-	maxFlateBlockTokens = 1 << 14
-	maxStoreBlockSize   = 65535
-	hashBits            = 17 // After 17 performance degrades
-	hashSize            = 1 << hashBits
-	hashMask            = (1 << hashBits) - 1
-	maxHashOffset       = 1 << 24
-
-	skipNever = math.MaxInt32
-)
-
-type compressionLevel struct {
-	level, good, lazy, nice, chain, fastSkipHashing int
-}
-
-var levels = []compressionLevel{
-	{0, 0, 0, 0, 0, 0}, // NoCompression.
-	{1, 0, 0, 0, 0, 0}, // BestSpeed uses a custom algorithm; see deflatefast.go.
-	// For levels 2-3 we don't bother trying with lazy matches.
-	{2, 4, 0, 16, 8, 5},
-	{3, 4, 0, 32, 32, 6},
-	// Levels 4-9 use increasingly more lazy matching
-	// and increasingly stringent conditions for "good enough".
-	{4, 4, 4, 16, 16, skipNever},
-	{5, 8, 16, 32, 32, skipNever},
-	{6, 8, 16, 128, 128, skipNever},
-	{7, 8, 32, 128, 256, skipNever},
-	{8, 32, 128, 258, 1024, skipNever},
-	{9, 32, 258, 258, 4096, skipNever},
-}
-
-type compressor struct {
-	compressionLevel
-
-	w          *huffmanBitWriter
-	bulkHasher func([]byte, []uint32)
-
-	// compression algorithm
-	fill      func(*compressor, []byte) int // copy data to window
-	step      func(*compressor)             // process window
-	sync      bool                          // requesting flush
-	bestSpeed *deflateFast                  // Encoder for BestSpeed
-
-	// Input hash chains
-	// hashHead[hashValue] contains the largest inputIndex with the specified hash value
-	// If hashHead[hashValue] is within the current window, then
-	// hashPrev[hashHead[hashValue] & windowMask] contains the previous index
-	// with the same hash value.
-	chainHead  int
-	hashHead   [hashSize]uint32
-	hashPrev   [windowSize]uint32
-	hashOffset int
-
-	// input window: unprocessed data is window[index:windowEnd]
-	index         int
-	window        []byte
-	windowEnd     int
-	blockStart    int  // window index where current tokens start
-	byteAvailable bool // if true, still need to process window[index-1].
-
-	// queued output tokens
-	tokens []token
-
-	// deflate state
-	length         int
-	offset         int
-	hash           uint32
-	maxInsertIndex int
-	err            error
-
-	// hashMatch must be able to contain hashes for the maximum match length.
-	hashMatch [maxMatchLength - 1]uint32
-}
-
-func (d *compressor) fillDeflate(b []byte) int {
-	if d.index >= 2*windowSize-(minMatchLength+maxMatchLength) {
-		// shift the window by windowSize
-		copy(d.window, d.window[windowSize:2*windowSize])
-		d.index -= windowSize
-		d.windowEnd -= windowSize
-		if d.blockStart >= windowSize {
-			d.blockStart -= windowSize
-		} else {
-			d.blockStart = math.MaxInt32
-		}
-		d.hashOffset += windowSize
-		if d.hashOffset > maxHashOffset {
-			delta := d.hashOffset - 1
-			d.hashOffset -= delta
-			d.chainHead -= delta
-
-			// Iterate over slices instead of arrays to avoid copying
-			// the entire table onto the stack (Issue #18625).
-			for i, v := range d.hashPrev[:] {
-				if int(v) > delta {
-					d.hashPrev[i] = uint32(int(v) - delta)
-				} else {
-					d.hashPrev[i] = 0
-				}
-			}
-			for i, v := range d.hashHead[:] {
-				if int(v) > delta {
-					d.hashHead[i] = uint32(int(v) - delta)
-				} else {
-					d.hashHead[i] = 0
-				}
-			}
-		}
-	}
-	n := copy(d.window[d.windowEnd:], b)
-	d.windowEnd += n
-	return n
-}
-
-func (d *compressor) writeBlock(tokens []token, index int) error {
-	if index > 0 {
-		var window []byte
-		if d.blockStart <= index {
-			window = d.window[d.blockStart:index]
-		}
-		d.blockStart = index
-		d.w.writeBlock(tokens, false, window)
-		return d.w.err
-	}
-	return nil
-}
-
-// fillWindow will fill the current window with the supplied
-// dictionary and calculate all hashes.
-// This is much faster than doing a full encode.
-// Should only be used after a reset.
-func (d *compressor) fillWindow(b []byte) {
-	// Do not fill window if we are in store-only mode.
-	if d.compressionLevel.level < 2 {
-		return
-	}
-	if d.index != 0 || d.windowEnd != 0 {
-		panic("internal error: fillWindow called with stale data")
-	}
-
-	// If we are given too much, cut it.
-	if len(b) > windowSize {
-		b = b[len(b)-windowSize:]
-	}
-	// Add all to window.
-	n := copy(d.window, b)
-
-	// Calculate 256 hashes at the time (more L1 cache hits)
-	loops := (n + 256 - minMatchLength) / 256
-	for j := 0; j < loops; j++ {
-		index := j * 256
-		end := index + 256 + minMatchLength - 1
-		if end > n {
-			end = n
-		}
-		toCheck := d.window[index:end]
-		dstSize := len(toCheck) - minMatchLength + 1
-
-		if dstSize <= 0 {
-			continue
-		}
-
-		dst := d.hashMatch[:dstSize]
-		d.bulkHasher(toCheck, dst)
-		var newH uint32
-		for i, val := range dst {
-			di := i + index
-			newH = val
-			hh := &d.hashHead[newH&hashMask]
-			// Get previous value with the same hash.
-			// Our chain should point to the previous value.
-			d.hashPrev[di&windowMask] = *hh
-			// Set the head of the hash chain to us.
-			*hh = uint32(di + d.hashOffset)
-		}
-		d.hash = newH
-	}
-	// Update window information.
-	d.windowEnd = n
-	d.index = n
-}
-
-// Try to find a match starting at index whose length is greater than prevSize.
-// We only look at chainCount possibilities before giving up.
-func (d *compressor) findMatch(pos int, prevHead int, prevLength int, lookahead int) (length, offset int, ok bool) {
-	minMatchLook := maxMatchLength
-	if lookahead < minMatchLook {
-		minMatchLook = lookahead
-	}
-
-	win := d.window[0 : pos+minMatchLook]
-
-	// We quit when we get a match that's at least nice long
-	nice := len(win) - pos
-	if d.nice < nice {
-		nice = d.nice
-	}
-
-	// If we've got a match that's good enough, only look in 1/4 the chain.
-	tries := d.chain
-	length = prevLength
-	if length >= d.good {
-		tries >>= 2
-	}
-
-	wEnd := win[pos+length]
-	wPos := win[pos:]
-	minIndex := pos - windowSize
-
-	for i := prevHead; tries > 0; tries-- {
-		if wEnd == win[i+length] {
-			n := matchLen(win[i:], wPos, minMatchLook)
-
-			if n > length && (n > minMatchLength || pos-i <= 4096) {
-				length = n
-				offset = pos - i
-				ok = true
-				if n >= nice {
-					// The match is good enough that we don't try to find a better one.
-					break
-				}
-				wEnd = win[pos+n]
-			}
-		}
-		if i == minIndex {
-			// hashPrev[i & windowMask] has already been overwritten, so stop now.
-			break
-		}
-		i = int(d.hashPrev[i&windowMask]) - d.hashOffset
-		if i < minIndex || i < 0 {
-			break
-		}
-	}
-	return
-}
-
-func (d *compressor) writeStoredBlock(buf []byte) error {
-	if d.w.writeStoredHeader(len(buf), false); d.w.err != nil {
-		return d.w.err
-	}
-	d.w.writeBytes(buf)
-	return d.w.err
-}
-
-const hashmul = 0x1e35a7bd
-
-// hash4 returns a hash representation of the first 4 bytes
-// of the supplied slice.
-// The caller must ensure that len(b) >= 4.
-func hash4(b []byte) uint32 {
-	return ((uint32(b[3]) | uint32(b[2])<<8 | uint32(b[1])<<16 | uint32(b[0])<<24) * hashmul) >> (32 - hashBits)
-}
-
-// bulkHash4 will compute hashes using the same
-// algorithm as hash4
-func bulkHash4(b []byte, dst []uint32) {
-	if len(b) < minMatchLength {
-		return
-	}
-	hb := uint32(b[3]) | uint32(b[2])<<8 | uint32(b[1])<<16 | uint32(b[0])<<24
-	dst[0] = (hb * hashmul) >> (32 - hashBits)
-	end := len(b) - minMatchLength + 1
-	for i := 1; i < end; i++ {
-		hb = (hb << 8) | uint32(b[i+3])
-		dst[i] = (hb * hashmul) >> (32 - hashBits)
-	}
-}
-
-// matchLen returns the number of matching bytes in a and b
-// up to length 'max'. Both slices must be at least 'max'
-// bytes in size.
-func matchLen(a, b []byte, max int) int {
-	a = a[:max]
-	b = b[:len(a)]
-	for i, av := range a {
-		if b[i] != av {
-			return i
-		}
-	}
-	return max
-}
-
-// encSpeed will compress and store the currently added data,
-// if enough has been accumulated or we at the end of the stream.
-// Any error that occurred will be in d.err
-func (d *compressor) encSpeed() {
-	// We only compress if we have maxStoreBlockSize.
-	if d.windowEnd < maxStoreBlockSize {
-		if !d.sync {
-			return
-		}
-
-		// Handle small sizes.
-		if d.windowEnd < 128 {
-			switch {
-			case d.windowEnd == 0:
-				return
-			case d.windowEnd <= 16:
-				d.err = d.writeStoredBlock(d.window[:d.windowEnd])
-			default:
-				d.w.writeBlockHuff(false, d.window[:d.windowEnd])
-				d.err = d.w.err
-			}
-			d.windowEnd = 0
-			d.bestSpeed.reset()
-			return
-		}
-
-	}
-	// Encode the block.
-	d.tokens = d.bestSpeed.encode(d.tokens[:0], d.window[:d.windowEnd])
-
-	// If we removed less than 1/16th, Huffman compress the block.
-	if len(d.tokens) > d.windowEnd-(d.windowEnd>>4) {
-		d.w.writeBlockHuff(false, d.window[:d.windowEnd])
-	} else {
-		d.w.writeBlockDynamic(d.tokens, false, d.window[:d.windowEnd])
-	}
-	d.err = d.w.err
-	d.windowEnd = 0
-}
-
-func (d *compressor) initDeflate() {
-	d.window = make([]byte, 2*windowSize)
-	d.hashOffset = 1
-	d.tokens = make([]token, 0, maxFlateBlockTokens+1)
-	d.length = minMatchLength - 1
-	d.offset = 0
-	d.byteAvailable = false
-	d.index = 0
-	d.hash = 0
-	d.chainHead = -1
-	d.bulkHasher = bulkHash4
-}
-
-func (d *compressor) deflate() {
-	if d.windowEnd-d.index < minMatchLength+maxMatchLength && !d.sync {
-		return
-	}
-
-	d.maxInsertIndex = d.windowEnd - (minMatchLength - 1)
-	if d.index < d.maxInsertIndex {
-		d.hash = hash4(d.window[d.index : d.index+minMatchLength])
-	}
-
-Loop:
-	for {
-		if d.index > d.windowEnd {
-			panic("index > windowEnd")
-		}
-		lookahead := d.windowEnd - d.index
-		if lookahead < minMatchLength+maxMatchLength {
-			if !d.sync {
-				break Loop
-			}
-			if d.index > d.windowEnd {
-				panic("index > windowEnd")
-			}
-			if lookahead == 0 {
-				// Flush current output block if any.
-				if d.byteAvailable {
-					// There is still one pending token that needs to be flushed
-					d.tokens = append(d.tokens, literalToken(uint32(d.window[d.index-1])))
-					d.byteAvailable = false
-				}
-				if len(d.tokens) > 0 {
-					if d.err = d.writeBlock(d.tokens, d.index); d.err != nil {
-						return
-					}
-					d.tokens = d.tokens[:0]
-				}
-				break Loop
-			}
-		}
-		if d.index < d.maxInsertIndex {
-			// Update the hash
-			d.hash = hash4(d.window[d.index : d.index+minMatchLength])
-			hh := &d.hashHead[d.hash&hashMask]
-			d.chainHead = int(*hh)
-			d.hashPrev[d.index&windowMask] = uint32(d.chainHead)
-			*hh = uint32(d.index + d.hashOffset)
-		}
-		prevLength := d.length
-		prevOffset := d.offset
-		d.length = minMatchLength - 1
-		d.offset = 0
-		minIndex := d.index - windowSize
-		if minIndex < 0 {
-			minIndex = 0
-		}
-
-		if d.chainHead-d.hashOffset >= minIndex &&
-			(d.fastSkipHashing != skipNever && lookahead > minMatchLength-1 ||
-				d.fastSkipHashing == skipNever && lookahead > prevLength && prevLength < d.lazy) {
-			if newLength, newOffset, ok := d.findMatch(d.index, d.chainHead-d.hashOffset, minMatchLength-1, lookahead); ok {
-				d.length = newLength
-				d.offset = newOffset
-			}
-		}
-		if d.fastSkipHashing != skipNever && d.length >= minMatchLength ||
-			d.fastSkipHashing == skipNever && prevLength >= minMatchLength && d.length <= prevLength {
-			// There was a match at the previous step, and the current match is
-			// not better. Output the previous match.
-			if d.fastSkipHashing != skipNever {
-				d.tokens = append(d.tokens, matchToken(uint32(d.length-baseMatchLength), uint32(d.offset-baseMatchOffset)))
-			} else {
-				d.tokens = append(d.tokens, matchToken(uint32(prevLength-baseMatchLength), uint32(prevOffset-baseMatchOffset)))
-			}
-			// Insert in the hash table all strings up to the end of the match.
-			// index and index-1 are already inserted. If there is not enough
-			// lookahead, the last two strings are not inserted into the hash
-			// table.
-			if d.length <= d.fastSkipHashing {
-				var newIndex int
-				if d.fastSkipHashing != skipNever {
-					newIndex = d.index + d.length
-				} else {
-					newIndex = d.index + prevLength - 1
-				}
-				index := d.index
-				for index++; index < newIndex; index++ {
-					if index < d.maxInsertIndex {
-						d.hash = hash4(d.window[index : index+minMatchLength])
-						// Get previous value with the same hash.
-						// Our chain should point to the previous value.
-						hh := &d.hashHead[d.hash&hashMask]
-						d.hashPrev[index&windowMask] = *hh
-						// Set the head of the hash chain to us.
-						*hh = uint32(index + d.hashOffset)
-					}
-				}
-				d.index = index
-
-				if d.fastSkipHashing == skipNever {
-					d.byteAvailable = false
-					d.length = minMatchLength - 1
-				}
-			} else {
-				// For matches this long, we don't bother inserting each individual
-				// item into the table.
-				d.index += d.length
-				if d.index < d.maxInsertIndex {
-					d.hash = hash4(d.window[d.index : d.index+minMatchLength])
-				}
-			}
-			if len(d.tokens) == maxFlateBlockTokens {
-				// The block includes the current character
-				if d.err = d.writeBlock(d.tokens, d.index); d.err != nil {
-					return
-				}
-				d.tokens = d.tokens[:0]
-			}
-		} else {
-			if d.fastSkipHashing != skipNever || d.byteAvailable {
-				i := d.index - 1
-				if d.fastSkipHashing != skipNever {
-					i = d.index
-				}
-				d.tokens = append(d.tokens, literalToken(uint32(d.window[i])))
-				if len(d.tokens) == maxFlateBlockTokens {
-					if d.err = d.writeBlock(d.tokens, i+1); d.err != nil {
-						return
-					}
-					d.tokens = d.tokens[:0]
-				}
-			}
-			d.index++
-			if d.fastSkipHashing == skipNever {
-				d.byteAvailable = true
-			}
-		}
-	}
-}
-
-func (d *compressor) fillStore(b []byte) int {
-	n := copy(d.window[d.windowEnd:], b)
-	d.windowEnd += n
-	return n
-}
-
-func (d *compressor) store() {
-	if d.windowEnd > 0 && (d.windowEnd == maxStoreBlockSize || d.sync) {
-		d.err = d.writeStoredBlock(d.window[:d.windowEnd])
-		d.windowEnd = 0
-	}
-}
-
-// storeHuff compresses and stores the currently added data
-// when the d.window is full or we are at the end of the stream.
-// Any error that occurred will be in d.err
-func (d *compressor) storeHuff() {
-	if d.windowEnd < len(d.window) && !d.sync || d.windowEnd == 0 {
-		return
-	}
-	d.w.writeBlockHuff(false, d.window[:d.windowEnd])
-	d.err = d.w.err
-	d.windowEnd = 0
-}
-
-func (d *compressor) write(b []byte) (n int, err error) {
-	if d.err != nil {
-		return 0, d.err
-	}
-	n = len(b)
-	for len(b) > 0 {
-		d.step(d)
-		b = b[d.fill(d, b):]
-		if d.err != nil {
-			return 0, d.err
-		}
-	}
-	return n, nil
-}
-
-func (d *compressor) syncFlush() error {
-	if d.err != nil {
-		return d.err
-	}
-	d.sync = true
-	d.step(d)
-	if d.err == nil {
-		d.w.writeStoredHeader(0, false)
-		d.w.flush()
-		d.err = d.w.err
-	}
-	d.sync = false
-	return d.err
-}
-
-func (d *compressor) init(w io.Writer, level int) (err error) {
-	d.w = newHuffmanBitWriter(w)
-
-	switch {
-	case level == NoCompression:
-		d.window = make([]byte, maxStoreBlockSize)
-		d.fill = (*compressor).fillStore
-		d.step = (*compressor).store
-	case level == HuffmanOnly:
-		d.window = make([]byte, maxStoreBlockSize)
-		d.fill = (*compressor).fillStore
-		d.step = (*compressor).storeHuff
-	case level == BestSpeed:
-		d.compressionLevel = levels[level]
-		d.window = make([]byte, maxStoreBlockSize)
-		d.fill = (*compressor).fillStore
-		d.step = (*compressor).encSpeed
-		d.bestSpeed = newDeflateFast()
-		d.tokens = make([]token, maxStoreBlockSize)
-	case level == DefaultCompression:
-		level = 6
-		fallthrough
-	case 2 <= level && level <= 9:
-		d.compressionLevel = levels[level]
-		d.initDeflate()
-		d.fill = (*compressor).fillDeflate
-		d.step = (*compressor).deflate
-	default:
-		return fmt.Errorf("flate: invalid compression level %d: want value in range [-2, 9]", level)
-	}
-	return nil
-}
-
-func (d *compressor) reset(w io.Writer) {
-	d.w.reset(w)
-	d.sync = false
-	d.err = nil
-	switch d.compressionLevel.level {
-	case NoCompression:
-		d.windowEnd = 0
-	case BestSpeed:
-		d.windowEnd = 0
-		d.tokens = d.tokens[:0]
-		d.bestSpeed.reset()
-	default:
-		d.chainHead = -1
-		for i := range d.hashHead {
-			d.hashHead[i] = 0
-		}
-		for i := range d.hashPrev {
-			d.hashPrev[i] = 0
-		}
-		d.hashOffset = 1
-		d.index, d.windowEnd = 0, 0
-		d.blockStart, d.byteAvailable = 0, false
-		d.tokens = d.tokens[:0]
-		d.length = minMatchLength - 1
-		d.offset = 0
-		d.hash = 0
-		d.maxInsertIndex = 0
-	}
-}
-
-func (d *compressor) close() error {
-	if d.err != nil {
-		return d.err
-	}
-	d.sync = true
-	d.step(d)
-	if d.err != nil {
-		return d.err
-	}
-	if d.w.writeStoredHeader(0, true); d.w.err != nil {
-		return d.w.err
-	}
-	d.w.flush()
-	return d.w.err
-}
-
-// NewWriter returns a new Writer compressing data at the given level.
-// Following zlib, levels range from 1 (BestSpeed) to 9 (BestCompression);
-// higher levels typically run slower but compress more. Level 0
-// (NoCompression) does not attempt any compression; it only adds the
-// necessary DEFLATE framing.
-// Level -1 (DefaultCompression) uses the default compression level.
-// Level -2 (HuffmanOnly) will use Huffman compression only, giving
-// a very fast compression for all types of input, but sacrificing considerable
-// compression efficiency.
-//
-// If level is in the range [-2, 9] then the error returned will be nil.
-// Otherwise the error returned will be non-nil.
-func NewWriter(w io.Writer, level int) (*Writer, error) {
-	var dw Writer
-	if err := dw.d.init(w, level); err != nil {
-		return nil, err
-	}
-	return &dw, nil
-}
-
-// NewWriterDict is like NewWriter but initializes the new
-// Writer with a preset dictionary. The returned Writer behaves
-// as if the dictionary had been written to it without producing
-// any compressed output. The compressed data written to w
-// can only be decompressed by a Reader initialized with the
-// same dictionary.
-func NewWriterDict(w io.Writer, level int, dict []byte) (*Writer, error) {
-	dw := &dictWriter{w}
-	zw, err := NewWriter(dw, level)
-	if err != nil {
-		return nil, err
-	}
-	zw.d.fillWindow(dict)
-	zw.dict = append(zw.dict, dict...) // duplicate dictionary for Reset method.
-	return zw, err
-}
-
-type dictWriter struct {
-	w io.Writer
-}
-
-func (w *dictWriter) Write(b []byte) (n int, err error) {
-	return w.w.Write(b)
-}
-
-// A Writer takes data written to it and writes the compressed
-// form of that data to an underlying writer (see NewWriter).
-type Writer struct {
-	d    compressor
-	dict []byte
-}
-
-// Write writes data to w, which will eventually write the
-// compressed form of data to its underlying writer.
-func (w *Writer) Write(data []byte) (n int, err error) {
-	return w.d.write(data)
-}
-
-// Flush flushes any pending data to the underlying writer.
-// It is useful mainly in compressed network protocols, to ensure that
-// a remote reader has enough data to reconstruct a packet.
-// Flush does not return until the data has been written.
-// Calling Flush when there is no pending data still causes the Writer
-// to emit a sync marker of at least 4 bytes.
-// If the underlying writer returns an error, Flush returns that error.
-//
-// In the terminology of the zlib library, Flush is equivalent to Z_SYNC_FLUSH.
-func (w *Writer) Flush() error {
-	// For more about flushing:
-	// https://www.bolet.org/~pornin/deflate-flush.html
-	return w.d.syncFlush()
-}
-
-// Close flushes and closes the writer.
-func (w *Writer) Close() error {
-	return w.d.close()
-}
-
-// Reset discards the writer's state and makes it equivalent to
-// the result of NewWriter or NewWriterDict called with dst
-// and w's level and dictionary.
-func (w *Writer) Reset(dst io.Writer) {
-	if dw, ok := w.d.w.writer.(*dictWriter); ok {
-		// w was created with NewWriterDict
-		dw.w = dst
-		w.d.reset(dw)
-		w.d.fillWindow(w.dict)
-	} else {
-		// w was created with NewWriter
-		w.d.reset(dst)
-	}
-}
diff --git a/contrib/go/_std_1.18/src/compress/flate/dict_decoder.go b/contrib/go/_std_1.18/src/compress/flate/dict_decoder.go
deleted file mode 100644
index 3b59d48351..0000000000
--- a/contrib/go/_std_1.18/src/compress/flate/dict_decoder.go
+++ /dev/null
@@ -1,182 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package flate
-
-// dictDecoder implements the LZ77 sliding dictionary as used in decompression.
-// LZ77 decompresses data through sequences of two forms of commands:
-//
-//	* Literal insertions: Runs of one or more symbols are inserted into the data
-//	stream as is. This is accomplished through the writeByte method for a
-//	single symbol, or combinations of writeSlice/writeMark for multiple symbols.
-//	Any valid stream must start with a literal insertion if no preset dictionary
-//	is used.
-//
-//	* Backward copies: Runs of one or more symbols are copied from previously
-//	emitted data. Backward copies come as the tuple (dist, length) where dist
-//	determines how far back in the stream to copy from and length determines how
-//	many bytes to copy. Note that it is valid for the length to be greater than
-//	the distance. Since LZ77 uses forward copies, that situation is used to
-//	perform a form of run-length encoding on repeated runs of symbols.
-//	The writeCopy and tryWriteCopy are used to implement this command.
-//
-// For performance reasons, this implementation performs little to no sanity
-// checks about the arguments. As such, the invariants documented for each
-// method call must be respected.
-type dictDecoder struct {
-	hist []byte // Sliding window history
-
-	// Invariant: 0 <= rdPos <= wrPos <= len(hist)
-	wrPos int  // Current output position in buffer
-	rdPos int  // Have emitted hist[:rdPos] already
-	full  bool // Has a full window length been written yet?
-}
-
-// init initializes dictDecoder to have a sliding window dictionary of the given
-// size. If a preset dict is provided, it will initialize the dictionary with
-// the contents of dict.
-func (dd *dictDecoder) init(size int, dict []byte) {
-	*dd = dictDecoder{hist: dd.hist}
-
-	if cap(dd.hist) < size {
-		dd.hist = make([]byte, size)
-	}
-	dd.hist = dd.hist[:size]
-
-	if len(dict) > len(dd.hist) {
-		dict = dict[len(dict)-len(dd.hist):]
-	}
-	dd.wrPos = copy(dd.hist, dict)
-	if dd.wrPos == len(dd.hist) {
-		dd.wrPos = 0
-		dd.full = true
-	}
-	dd.rdPos = dd.wrPos
-}
-
-// histSize reports the total amount of historical data in the dictionary.
-func (dd *dictDecoder) histSize() int {
-	if dd.full {
-		return len(dd.hist)
-	}
-	return dd.wrPos
-}
-
-// availRead reports the number of bytes that can be flushed by readFlush.
-func (dd *dictDecoder) availRead() int {
-	return dd.wrPos - dd.rdPos
-}
-
-// availWrite reports the available amount of output buffer space.
-func (dd *dictDecoder) availWrite() int {
-	return len(dd.hist) - dd.wrPos
-}
-
-// writeSlice returns a slice of the available buffer to write data to.
-//
-// This invariant will be kept: len(s) <= availWrite()
-func (dd *dictDecoder) writeSlice() []byte {
-	return dd.hist[dd.wrPos:]
-}
-
-// writeMark advances the writer pointer by cnt.
-//
-// This invariant must be kept: 0 <= cnt <= availWrite()
-func (dd *dictDecoder) writeMark(cnt int) {
-	dd.wrPos += cnt
-}
-
-// writeByte writes a single byte to the dictionary.
-//
-// This invariant must be kept: 0 < availWrite()
-func (dd *dictDecoder) writeByte(c byte) {
-	dd.hist[dd.wrPos] = c
-	dd.wrPos++
-}
-
-// writeCopy copies a string at a given (dist, length) to the output.
-// This returns the number of bytes copied and may be less than the requested
-// length if the available space in the output buffer is too small.
-//
-// This invariant must be kept: 0 < dist <= histSize()
-func (dd *dictDecoder) writeCopy(dist, length int) int {
-	dstBase := dd.wrPos
-	dstPos := dstBase
-	srcPos := dstPos - dist
-	endPos := dstPos + length
-	if endPos > len(dd.hist) {
-		endPos = len(dd.hist)
-	}
-
-	// Copy non-overlapping section after destination position.
-	//
-	// This section is non-overlapping in that the copy length for this section
-	// is always less than or equal to the backwards distance. This can occur
-	// if a distance refers to data that wraps-around in the buffer.
-	// Thus, a backwards copy is performed here; that is, the exact bytes in
-	// the source prior to the copy is placed in the destination.
-	if srcPos < 0 {
-		srcPos += len(dd.hist)
-		dstPos += copy(dd.hist[dstPos:endPos], dd.hist[srcPos:])
-		srcPos = 0
-	}
-
-	// Copy possibly overlapping section before destination position.
-	//
-	// This section can overlap if the copy length for this section is larger
-	// than the backwards distance. This is allowed by LZ77 so that repeated
-	// strings can be succinctly represented using (dist, length) pairs.
-	// Thus, a forwards copy is performed here; that is, the bytes copied is
-	// possibly dependent on the resulting bytes in the destination as the copy
-	// progresses along. This is functionally equivalent to the following:
-	//
-	//	for i := 0; i < endPos-dstPos; i++ {
-	//		dd.hist[dstPos+i] = dd.hist[srcPos+i]
-	//	}
-	//	dstPos = endPos
-	//
-	for dstPos < endPos {
-		dstPos += copy(dd.hist[dstPos:endPos], dd.hist[srcPos:dstPos])
-	}
-
-	dd.wrPos = dstPos
-	return dstPos - dstBase
-}
-
-// tryWriteCopy tries to copy a string at a given (distance, length) to the
-// output. This specialized version is optimized for short distances.
-//
-// This method is designed to be inlined for performance reasons.
-//
-// This invariant must be kept: 0 < dist <= histSize()
-func (dd *dictDecoder) tryWriteCopy(dist, length int) int {
-	dstPos := dd.wrPos
-	endPos := dstPos + length
-	if dstPos < dist || endPos > len(dd.hist) {
-		return 0
-	}
-	dstBase := dstPos
-	srcPos := dstPos - dist
-
-	// Copy possibly overlapping section before destination position.
-	for dstPos < endPos {
-		dstPos += copy(dd.hist[dstPos:endPos], dd.hist[srcPos:dstPos])
-	}
-
-	dd.wrPos = dstPos
-	return dstPos - dstBase
-}
-
-// readFlush returns a slice of the historical buffer that is ready to be
-// emitted to the user. The data returned by readFlush must be fully consumed
-// before calling any other dictDecoder methods.
-func (dd *dictDecoder) readFlush() []byte {
-	toRead := dd.hist[dd.rdPos:dd.wrPos]
-	dd.rdPos = dd.wrPos
-	if dd.wrPos == len(dd.hist) {
-		dd.wrPos, dd.rdPos = 0, 0
-		dd.full = true
-	}
-	return toRead
-}
diff --git a/contrib/go/_std_1.18/src/compress/flate/huffman_bit_writer.go b/contrib/go/_std_1.18/src/compress/flate/huffman_bit_writer.go
deleted file mode 100644
index b3ae76d082..0000000000
--- a/contrib/go/_std_1.18/src/compress/flate/huffman_bit_writer.go
+++ /dev/null
@@ -1,704 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package flate
-
-import (
-	"io"
-)
-
-const (
-	// The largest offset code.
-	offsetCodeCount = 30
-
-	// The special code used to mark the end of a block.
-	endBlockMarker = 256
-
-	// The first length code.
-	lengthCodesStart = 257
-
-	// The number of codegen codes.
-	codegenCodeCount = 19
-	badCode          = 255
-
-	// bufferFlushSize indicates the buffer size
-	// after which bytes are flushed to the writer.
-	// Should preferably be a multiple of 6, since
-	// we accumulate 6 bytes between writes to the buffer.
-	bufferFlushSize = 240
-
-	// bufferSize is the actual output byte buffer size.
-	// It must have additional headroom for a flush
-	// which can contain up to 8 bytes.
-	bufferSize = bufferFlushSize + 8
-)
-
-// The number of extra bits needed by length code X - LENGTH_CODES_START.
-var lengthExtraBits = []int8{
-	/* 257 */ 0, 0, 0,
-	/* 260 */ 0, 0, 0, 0, 0, 1, 1, 1, 1, 2,
-	/* 270 */ 2, 2, 2, 3, 3, 3, 3, 4, 4, 4,
-	/* 280 */ 4, 5, 5, 5, 5, 0,
-}
-
-// The length indicated by length code X - LENGTH_CODES_START.
-var lengthBase = []uint32{
-	0, 1, 2, 3, 4, 5, 6, 7, 8, 10,
-	12, 14, 16, 20, 24, 28, 32, 40, 48, 56,
-	64, 80, 96, 112, 128, 160, 192, 224, 255,
-}
-
-// offset code word extra bits.
-var offsetExtraBits = []int8{
-	0, 0, 0, 0, 1, 1, 2, 2, 3, 3,
-	4, 4, 5, 5, 6, 6, 7, 7, 8, 8,
-	9, 9, 10, 10, 11, 11, 12, 12, 13, 13,
-}
-
-var offsetBase = []uint32{
-	0x000000, 0x000001, 0x000002, 0x000003, 0x000004,
-	0x000006, 0x000008, 0x00000c, 0x000010, 0x000018,
-	0x000020, 0x000030, 0x000040, 0x000060, 0x000080,
-	0x0000c0, 0x000100, 0x000180, 0x000200, 0x000300,
-	0x000400, 0x000600, 0x000800, 0x000c00, 0x001000,
-	0x001800, 0x002000, 0x003000, 0x004000, 0x006000,
-}
-
-// The odd order in which the codegen code sizes are written.
-var codegenOrder = []uint32{16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}
-
-type huffmanBitWriter struct {
-	// writer is the underlying writer.
-	// Do not use it directly; use the write method, which ensures
-	// that Write errors are sticky.
-	writer io.Writer
-
-	// Data waiting to be written is bytes[0:nbytes]
-	// and then the low nbits of bits.  Data is always written
-	// sequentially into the bytes array.
-	bits            uint64
-	nbits           uint
-	bytes           [bufferSize]byte
-	codegenFreq     [codegenCodeCount]int32
-	nbytes          int
-	literalFreq     []int32
-	offsetFreq      []int32
-	codegen         []uint8
-	literalEncoding *huffmanEncoder
-	offsetEncoding  *huffmanEncoder
-	codegenEncoding *huffmanEncoder
-	err             error
-}
-
-func newHuffmanBitWriter(w io.Writer) *huffmanBitWriter {
-	return &huffmanBitWriter{
-		writer:          w,
-		literalFreq:     make([]int32, maxNumLit),
-		offsetFreq:      make([]int32, offsetCodeCount),
-		codegen:         make([]uint8, maxNumLit+offsetCodeCount+1),
-		literalEncoding: newHuffmanEncoder(maxNumLit),
-		codegenEncoding: newHuffmanEncoder(codegenCodeCount),
-		offsetEncoding:  newHuffmanEncoder(offsetCodeCount),
-	}
-}
-
-func (w *huffmanBitWriter) reset(writer io.Writer) {
-	w.writer = writer
-	w.bits, w.nbits, w.nbytes, w.err = 0, 0, 0, nil
-}
-
-func (w *huffmanBitWriter) flush() {
-	if w.err != nil {
-		w.nbits = 0
-		return
-	}
-	n := w.nbytes
-	for w.nbits != 0 {
-		w.bytes[n] = byte(w.bits)
-		w.bits >>= 8
-		if w.nbits > 8 { // Avoid underflow
-			w.nbits -= 8
-		} else {
-			w.nbits = 0
-		}
-		n++
-	}
-	w.bits = 0
-	w.write(w.bytes[:n])
-	w.nbytes = 0
-}
-
-func (w *huffmanBitWriter) write(b []byte) {
-	if w.err != nil {
-		return
-	}
-	_, w.err = w.writer.Write(b)
-}
-
-func (w *huffmanBitWriter) writeBits(b int32, nb uint) {
-	if w.err != nil {
-		return
-	}
-	w.bits |= uint64(b) << w.nbits
-	w.nbits += nb
-	if w.nbits >= 48 {
-		bits := w.bits
-		w.bits >>= 48
-		w.nbits -= 48
-		n := w.nbytes
-		bytes := w.bytes[n : n+6]
-		bytes[0] = byte(bits)
-		bytes[1] = byte(bits >> 8)
-		bytes[2] = byte(bits >> 16)
-		bytes[3] = byte(bits >> 24)
-		bytes[4] = byte(bits >> 32)
-		bytes[5] = byte(bits >> 40)
-		n += 6
-		if n >= bufferFlushSize {
-			w.write(w.bytes[:n])
-			n = 0
-		}
-		w.nbytes = n
-	}
-}
-
-func (w *huffmanBitWriter) writeBytes(bytes []byte) {
-	if w.err != nil {
-		return
-	}
-	n := w.nbytes
-	if w.nbits&7 != 0 {
-		w.err = InternalError("writeBytes with unfinished bits")
-		return
-	}
-	for w.nbits != 0 {
-		w.bytes[n] = byte(w.bits)
-		w.bits >>= 8
-		w.nbits -= 8
-		n++
-	}
-	if n != 0 {
-		w.write(w.bytes[:n])
-	}
-	w.nbytes = 0
-	w.write(bytes)
-}
-
-// RFC 1951 3.2.7 specifies a special run-length encoding for specifying
-// the literal and offset lengths arrays (which are concatenated into a single
-// array).  This method generates that run-length encoding.
-//
-// The result is written into the codegen array, and the frequencies
-// of each code is written into the codegenFreq array.
-// Codes 0-15 are single byte codes. Codes 16-18 are followed by additional
-// information. Code badCode is an end marker
-//
-//  numLiterals      The number of literals in literalEncoding
-//  numOffsets       The number of offsets in offsetEncoding
-//  litenc, offenc   The literal and offset encoder to use
-func (w *huffmanBitWriter) generateCodegen(numLiterals int, numOffsets int, litEnc, offEnc *huffmanEncoder) {
-	for i := range w.codegenFreq {
-		w.codegenFreq[i] = 0
-	}
-	// Note that we are using codegen both as a temporary variable for holding
-	// a copy of the frequencies, and as the place where we put the result.
-	// This is fine because the output is always shorter than the input used
-	// so far.
-	codegen := w.codegen // cache
-	// Copy the concatenated code sizes to codegen. Put a marker at the end.
-	cgnl := codegen[:numLiterals]
-	for i := range cgnl {
-		cgnl[i] = uint8(litEnc.codes[i].len)
-	}
-
-	cgnl = codegen[numLiterals : numLiterals+numOffsets]
-	for i := range cgnl {
-		cgnl[i] = uint8(offEnc.codes[i].len)
-	}
-	codegen[numLiterals+numOffsets] = badCode
-
-	size := codegen[0]
-	count := 1
-	outIndex := 0
-	for inIndex := 1; size != badCode; inIndex++ {
-		// INVARIANT: We have seen "count" copies of size that have not yet
-		// had output generated for them.
-		nextSize := codegen[inIndex]
-		if nextSize == size {
-			count++
-			continue
-		}
-		// We need to generate codegen indicating "count" of size.
-		if size != 0 {
-			codegen[outIndex] = size
-			outIndex++
-			w.codegenFreq[size]++
-			count--
-			for count >= 3 {
-				n := 6
-				if n > count {
-					n = count
-				}
-				codegen[outIndex] = 16
-				outIndex++
-				codegen[outIndex] = uint8(n - 3)
-				outIndex++
-				w.codegenFreq[16]++
-				count -= n
-			}
-		} else {
-			for count >= 11 {
-				n := 138
-				if n > count {
-					n = count
-				}
-				codegen[outIndex] = 18
-				outIndex++
-				codegen[outIndex] = uint8(n - 11)
-				outIndex++
-				w.codegenFreq[18]++
-				count -= n
-			}
-			if count >= 3 {
-				// count >= 3 && count <= 10
-				codegen[outIndex] = 17
-				outIndex++
-				codegen[outIndex] = uint8(count - 3)
-				outIndex++
-				w.codegenFreq[17]++
-				count = 0
-			}
-		}
-		count--
-		for ; count >= 0; count-- {
-			codegen[outIndex] = size
-			outIndex++
-			w.codegenFreq[size]++
-		}
-		// Set up invariant for next time through the loop.
-		size = nextSize
-		count = 1
-	}
-	// Marker indicating the end of the codegen.
-	codegen[outIndex] = badCode
-}
-
-// dynamicSize returns the size of dynamically encoded data in bits.
-func (w *huffmanBitWriter) dynamicSize(litEnc, offEnc *huffmanEncoder, extraBits int) (size, numCodegens int) {
-	numCodegens = len(w.codegenFreq)
-	for numCodegens > 4 && w.codegenFreq[codegenOrder[numCodegens-1]] == 0 {
-		numCodegens--
-	}
-	header := 3 + 5 + 5 + 4 + (3 * numCodegens) +
-		w.codegenEncoding.bitLength(w.codegenFreq[:]) +
-		int(w.codegenFreq[16])*2 +
-		int(w.codegenFreq[17])*3 +
-		int(w.codegenFreq[18])*7
-	size = header +
-		litEnc.bitLength(w.literalFreq) +
-		offEnc.bitLength(w.offsetFreq) +
-		extraBits
-
-	return size, numCodegens
-}
-
-// fixedSize returns the size of dynamically encoded data in bits.
-func (w *huffmanBitWriter) fixedSize(extraBits int) int {
-	return 3 +
-		fixedLiteralEncoding.bitLength(w.literalFreq) +
-		fixedOffsetEncoding.bitLength(w.offsetFreq) +
-		extraBits
-}
-
-// storedSize calculates the stored size, including header.
-// The function returns the size in bits and whether the block
-// fits inside a single block.
-func (w *huffmanBitWriter) storedSize(in []byte) (int, bool) {
-	if in == nil {
-		return 0, false
-	}
-	if len(in) <= maxStoreBlockSize {
-		return (len(in) + 5) * 8, true
-	}
-	return 0, false
-}
-
-func (w *huffmanBitWriter) writeCode(c hcode) {
-	if w.err != nil {
-		return
-	}
-	w.bits |= uint64(c.code) << w.nbits
-	w.nbits += uint(c.len)
-	if w.nbits >= 48 {
-		bits := w.bits
-		w.bits >>= 48
-		w.nbits -= 48
-		n := w.nbytes
-		bytes := w.bytes[n : n+6]
-		bytes[0] = byte(bits)
-		bytes[1] = byte(bits >> 8)
-		bytes[2] = byte(bits >> 16)
-		bytes[3] = byte(bits >> 24)
-		bytes[4] = byte(bits >> 32)
-		bytes[5] = byte(bits >> 40)
-		n += 6
-		if n >= bufferFlushSize {
-			w.write(w.bytes[:n])
-			n = 0
-		}
-		w.nbytes = n
-	}
-}
-
-// Write the header of a dynamic Huffman block to the output stream.
-//
-//  numLiterals  The number of literals specified in codegen
-//  numOffsets   The number of offsets specified in codegen
-//  numCodegens  The number of codegens used in codegen
-func (w *huffmanBitWriter) writeDynamicHeader(numLiterals int, numOffsets int, numCodegens int, isEof bool) {
-	if w.err != nil {
-		return
-	}
-	var firstBits int32 = 4
-	if isEof {
-		firstBits = 5
-	}
-	w.writeBits(firstBits, 3)
-	w.writeBits(int32(numLiterals-257), 5)
-	w.writeBits(int32(numOffsets-1), 5)
-	w.writeBits(int32(numCodegens-4), 4)
-
-	for i := 0; i < numCodegens; i++ {
-		value := uint(w.codegenEncoding.codes[codegenOrder[i]].len)
-		w.writeBits(int32(value), 3)
-	}
-
-	i := 0
-	for {
-		var codeWord int = int(w.codegen[i])
-		i++
-		if codeWord == badCode {
-			break
-		}
-		w.writeCode(w.codegenEncoding.codes[uint32(codeWord)])
-
-		switch codeWord {
-		case 16:
-			w.writeBits(int32(w.codegen[i]), 2)
-			i++
-			break
-		case 17:
-			w.writeBits(int32(w.codegen[i]), 3)
-			i++
-			break
-		case 18:
-			w.writeBits(int32(w.codegen[i]), 7)
-			i++
-			break
-		}
-	}
-}
-
-func (w *huffmanBitWriter) writeStoredHeader(length int, isEof bool) {
-	if w.err != nil {
-		return
-	}
-	var flag int32
-	if isEof {
-		flag = 1
-	}
-	w.writeBits(flag, 3)
-	w.flush()
-	w.writeBits(int32(length), 16)
-	w.writeBits(int32(^uint16(length)), 16)
-}
-
-func (w *huffmanBitWriter) writeFixedHeader(isEof bool) {
-	if w.err != nil {
-		return
-	}
-	// Indicate that we are a fixed Huffman block
-	var value int32 = 2
-	if isEof {
-		value = 3
-	}
-	w.writeBits(value, 3)
-}
-
-// writeBlock will write a block of tokens with the smallest encoding.
-// The original input can be supplied, and if the huffman encoded data
-// is larger than the original bytes, the data will be written as a
-// stored block.
-// If the input is nil, the tokens will always be Huffman encoded.
-func (w *huffmanBitWriter) writeBlock(tokens []token, eof bool, input []byte) {
-	if w.err != nil {
-		return
-	}
-
-	tokens = append(tokens, endBlockMarker)
-	numLiterals, numOffsets := w.indexTokens(tokens)
-
-	var extraBits int
-	storedSize, storable := w.storedSize(input)
-	if storable {
-		// We only bother calculating the costs of the extra bits required by
-		// the length of offset fields (which will be the same for both fixed
-		// and dynamic encoding), if we need to compare those two encodings
-		// against stored encoding.
-		for lengthCode := lengthCodesStart + 8; lengthCode < numLiterals; lengthCode++ {
-			// First eight length codes have extra size = 0.
-			extraBits += int(w.literalFreq[lengthCode]) * int(lengthExtraBits[lengthCode-lengthCodesStart])
-		}
-		for offsetCode := 4; offsetCode < numOffsets; offsetCode++ {
-			// First four offset codes have extra size = 0.
-			extraBits += int(w.offsetFreq[offsetCode]) * int(offsetExtraBits[offsetCode])
-		}
-	}
-
-	// Figure out smallest code.
-	// Fixed Huffman baseline.
-	var literalEncoding = fixedLiteralEncoding
-	var offsetEncoding = fixedOffsetEncoding
-	var size = w.fixedSize(extraBits)
-
-	// Dynamic Huffman?
-	var numCodegens int
-
-	// Generate codegen and codegenFrequencies, which indicates how to encode
-	// the literalEncoding and the offsetEncoding.
-	w.generateCodegen(numLiterals, numOffsets, w.literalEncoding, w.offsetEncoding)
-	w.codegenEncoding.generate(w.codegenFreq[:], 7)
-	dynamicSize, numCodegens := w.dynamicSize(w.literalEncoding, w.offsetEncoding, extraBits)
-
-	if dynamicSize < size {
-		size = dynamicSize
-		literalEncoding = w.literalEncoding
-		offsetEncoding = w.offsetEncoding
-	}
-
-	// Stored bytes?
-	if storable && storedSize < size {
-		w.writeStoredHeader(len(input), eof)
-		w.writeBytes(input)
-		return
-	}
-
-	// Huffman.
-	if literalEncoding == fixedLiteralEncoding {
-		w.writeFixedHeader(eof)
-	} else {
-		w.writeDynamicHeader(numLiterals, numOffsets, numCodegens, eof)
-	}
-
-	// Write the tokens.
-	w.writeTokens(tokens, literalEncoding.codes, offsetEncoding.codes)
-}
-
-// writeBlockDynamic encodes a block using a dynamic Huffman table.
-// This should be used if the symbols used have a disproportionate
-// histogram distribution.
-// If input is supplied and the compression savings are below 1/16th of the
-// input size the block is stored.
-func (w *huffmanBitWriter) writeBlockDynamic(tokens []token, eof bool, input []byte) {
-	if w.err != nil {
-		return
-	}
-
-	tokens = append(tokens, endBlockMarker)
-	numLiterals, numOffsets := w.indexTokens(tokens)
-
-	// Generate codegen and codegenFrequencies, which indicates how to encode
-	// the literalEncoding and the offsetEncoding.
-	w.generateCodegen(numLiterals, numOffsets, w.literalEncoding, w.offsetEncoding)
-	w.codegenEncoding.generate(w.codegenFreq[:], 7)
-	size, numCodegens := w.dynamicSize(w.literalEncoding, w.offsetEncoding, 0)
-
-	// Store bytes, if we don't get a reasonable improvement.
-	if ssize, storable := w.storedSize(input); storable && ssize < (size+size>>4) {
-		w.writeStoredHeader(len(input), eof)
-		w.writeBytes(input)
-		return
-	}
-
-	// Write Huffman table.
-	w.writeDynamicHeader(numLiterals, numOffsets, numCodegens, eof)
-
-	// Write the tokens.
-	w.writeTokens(tokens, w.literalEncoding.codes, w.offsetEncoding.codes)
-}
-
-// indexTokens indexes a slice of tokens, and updates
-// literalFreq and offsetFreq, and generates literalEncoding
-// and offsetEncoding.
-// The number of literal and offset tokens is returned.
-func (w *huffmanBitWriter) indexTokens(tokens []token) (numLiterals, numOffsets int) {
-	for i := range w.literalFreq {
-		w.literalFreq[i] = 0
-	}
-	for i := range w.offsetFreq {
-		w.offsetFreq[i] = 0
-	}
-
-	for _, t := range tokens {
-		if t < matchType {
-			w.literalFreq[t.literal()]++
-			continue
-		}
-		length := t.length()
-		offset := t.offset()
-		w.literalFreq[lengthCodesStart+lengthCode(length)]++
-		w.offsetFreq[offsetCode(offset)]++
-	}
-
-	// get the number of literals
-	numLiterals = len(w.literalFreq)
-	for w.literalFreq[numLiterals-1] == 0 {
-		numLiterals--
-	}
-	// get the number of offsets
-	numOffsets = len(w.offsetFreq)
-	for numOffsets > 0 && w.offsetFreq[numOffsets-1] == 0 {
-		numOffsets--
-	}
-	if numOffsets == 0 {
-		// We haven't found a single match. If we want to go with the dynamic encoding,
-		// we should count at least one offset to be sure that the offset huffman tree could be encoded.
-		w.offsetFreq[0] = 1
-		numOffsets = 1
-	}
-	w.literalEncoding.generate(w.literalFreq, 15)
-	w.offsetEncoding.generate(w.offsetFreq, 15)
-	return
-}
-
-// writeTokens writes a slice of tokens to the output.
-// codes for literal and offset encoding must be supplied.
-func (w *huffmanBitWriter) writeTokens(tokens []token, leCodes, oeCodes []hcode) {
-	if w.err != nil {
-		return
-	}
-	for _, t := range tokens {
-		if t < matchType {
-			w.writeCode(leCodes[t.literal()])
-			continue
-		}
-		// Write the length
-		length := t.length()
-		lengthCode := lengthCode(length)
-		w.writeCode(leCodes[lengthCode+lengthCodesStart])
-		extraLengthBits := uint(lengthExtraBits[lengthCode])
-		if extraLengthBits > 0 {
-			extraLength := int32(length - lengthBase[lengthCode])
-			w.writeBits(extraLength, extraLengthBits)
-		}
-		// Write the offset
-		offset := t.offset()
-		offsetCode := offsetCode(offset)
-		w.writeCode(oeCodes[offsetCode])
-		extraOffsetBits := uint(offsetExtraBits[offsetCode])
-		if extraOffsetBits > 0 {
-			extraOffset := int32(offset - offsetBase[offsetCode])
-			w.writeBits(extraOffset, extraOffsetBits)
-		}
-	}
-}
-
-// huffOffset is a static offset encoder used for huffman only encoding.
-// It can be reused since we will not be encoding offset values.
-var huffOffset *huffmanEncoder
-
-func init() {
-	offsetFreq := make([]int32, offsetCodeCount)
-	offsetFreq[0] = 1
-	huffOffset = newHuffmanEncoder(offsetCodeCount)
-	huffOffset.generate(offsetFreq, 15)
-}
-
-// writeBlockHuff encodes a block of bytes as either
-// Huffman encoded literals or uncompressed bytes if the
-// results only gains very little from compression.
-func (w *huffmanBitWriter) writeBlockHuff(eof bool, input []byte) {
-	if w.err != nil {
-		return
-	}
-
-	// Clear histogram
-	for i := range w.literalFreq {
-		w.literalFreq[i] = 0
-	}
-
-	// Add everything as literals
-	histogram(input, w.literalFreq)
-
-	w.literalFreq[endBlockMarker] = 1
-
-	const numLiterals = endBlockMarker + 1
-	w.offsetFreq[0] = 1
-	const numOffsets = 1
-
-	w.literalEncoding.generate(w.literalFreq, 15)
-
-	// Figure out smallest code.
-	// Always use dynamic Huffman or Store
-	var numCodegens int
-
-	// Generate codegen and codegenFrequencies, which indicates how to encode
-	// the literalEncoding and the offsetEncoding.
-	w.generateCodegen(numLiterals, numOffsets, w.literalEncoding, huffOffset)
-	w.codegenEncoding.generate(w.codegenFreq[:], 7)
-	size, numCodegens := w.dynamicSize(w.literalEncoding, huffOffset, 0)
-
-	// Store bytes, if we don't get a reasonable improvement.
-	if ssize, storable := w.storedSize(input); storable && ssize < (size+size>>4) {
-		w.writeStoredHeader(len(input), eof)
-		w.writeBytes(input)
-		return
-	}
-
-	// Huffman.
-	w.writeDynamicHeader(numLiterals, numOffsets, numCodegens, eof)
-	encoding := w.literalEncoding.codes[:257]
-	n := w.nbytes
-	for _, t := range input {
-		// Bitwriting inlined, ~30% speedup
-		c := encoding[t]
-		w.bits |= uint64(c.code) << w.nbits
-		w.nbits += uint(c.len)
-		if w.nbits < 48 {
-			continue
-		}
-		// Store 6 bytes
-		bits := w.bits
-		w.bits >>= 48
-		w.nbits -= 48
-		bytes := w.bytes[n : n+6]
-		bytes[0] = byte(bits)
-		bytes[1] = byte(bits >> 8)
-		bytes[2] = byte(bits >> 16)
-		bytes[3] = byte(bits >> 24)
-		bytes[4] = byte(bits >> 32)
-		bytes[5] = byte(bits >> 40)
-		n += 6
-		if n < bufferFlushSize {
-			continue
-		}
-		w.write(w.bytes[:n])
-		if w.err != nil {
-			return // Return early in the event of write failures
-		}
-		n = 0
-	}
-	w.nbytes = n
-	w.writeCode(encoding[endBlockMarker])
-}
-
-// histogram accumulates a histogram of b in h.
-//
-// len(h) must be >= 256, and h's elements must be all zeroes.
-func histogram(b []byte, h []int32) {
-	h = h[:256]
-	for _, t := range b {
-		h[t]++
-	}
-}
diff --git a/contrib/go/_std_1.18/src/compress/flate/huffman_code.go b/contrib/go/_std_1.18/src/compress/flate/huffman_code.go
deleted file mode 100644
index 891537ed5e..0000000000
--- a/contrib/go/_std_1.18/src/compress/flate/huffman_code.go
+++ /dev/null
@@ -1,349 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package flate
-
-import (
-	"math"
-	"math/bits"
-	"sort"
-)
-
-// hcode is a huffman code with a bit code and bit length.
-type hcode struct {
-	code, len uint16
-}
-
-type huffmanEncoder struct {
-	codes     []hcode
-	freqcache []literalNode
-	bitCount  [17]int32
-	lns       byLiteral // stored to avoid repeated allocation in generate
-	lfs       byFreq    // stored to avoid repeated allocation in generate
-}
-
-type literalNode struct {
-	literal uint16
-	freq    int32
-}
-
-// A levelInfo describes the state of the constructed tree for a given depth.
-type levelInfo struct {
-	// Our level.  for better printing
-	level int32
-
-	// The frequency of the last node at this level
-	lastFreq int32
-
-	// The frequency of the next character to add to this level
-	nextCharFreq int32
-
-	// The frequency of the next pair (from level below) to add to this level.
-	// Only valid if the "needed" value of the next lower level is 0.
-	nextPairFreq int32
-
-	// The number of chains remaining to generate for this level before moving
-	// up to the next level
-	needed int32
-}
-
-// set sets the code and length of an hcode.
-func (h *hcode) set(code uint16, length uint16) {
-	h.len = length
-	h.code = code
-}
-
-func maxNode() literalNode { return literalNode{math.MaxUint16, math.MaxInt32} }
-
-func newHuffmanEncoder(size int) *huffmanEncoder {
-	return &huffmanEncoder{codes: make([]hcode, size)}
-}
-
-// Generates a HuffmanCode corresponding to the fixed literal table
-func generateFixedLiteralEncoding() *huffmanEncoder {
-	h := newHuffmanEncoder(maxNumLit)
-	codes := h.codes
-	var ch uint16
-	for ch = 0; ch < maxNumLit; ch++ {
-		var bits uint16
-		var size uint16
-		switch {
-		case ch < 144:
-			// size 8, 000110000  .. 10111111
-			bits = ch + 48
-			size = 8
-			break
-		case ch < 256:
-			// size 9, 110010000 .. 111111111
-			bits = ch + 400 - 144
-			size = 9
-			break
-		case ch < 280:
-			// size 7, 0000000 .. 0010111
-			bits = ch - 256
-			size = 7
-			break
-		default:
-			// size 8, 11000000 .. 11000111
-			bits = ch + 192 - 280
-			size = 8
-		}
-		codes[ch] = hcode{code: reverseBits(bits, byte(size)), len: size}
-	}
-	return h
-}
-
-func generateFixedOffsetEncoding() *huffmanEncoder {
-	h := newHuffmanEncoder(30)
-	codes := h.codes
-	for ch := range codes {
-		codes[ch] = hcode{code: reverseBits(uint16(ch), 5), len: 5}
-	}
-	return h
-}
-
-var fixedLiteralEncoding *huffmanEncoder = generateFixedLiteralEncoding()
-var fixedOffsetEncoding *huffmanEncoder = generateFixedOffsetEncoding()
-
-func (h *huffmanEncoder) bitLength(freq []int32) int {
-	var total int
-	for i, f := range freq {
-		if f != 0 {
-			total += int(f) * int(h.codes[i].len)
-		}
-	}
-	return total
-}
-
-const maxBitsLimit = 16
-
-// Return the number of literals assigned to each bit size in the Huffman encoding
-//
-// This method is only called when list.length >= 3
-// The cases of 0, 1, and 2 literals are handled by special case code.
-//
-// list  An array of the literals with non-zero frequencies
-//             and their associated frequencies. The array is in order of increasing
-//             frequency, and has as its last element a special element with frequency
-//             MaxInt32
-// maxBits     The maximum number of bits that should be used to encode any literal.
-//             Must be less than 16.
-// return      An integer array in which array[i] indicates the number of literals
-//             that should be encoded in i bits.
-func (h *huffmanEncoder) bitCounts(list []literalNode, maxBits int32) []int32 {
-	if maxBits >= maxBitsLimit {
-		panic("flate: maxBits too large")
-	}
-	n := int32(len(list))
-	list = list[0 : n+1]
-	list[n] = maxNode()
-
-	// The tree can't have greater depth than n - 1, no matter what. This
-	// saves a little bit of work in some small cases
-	if maxBits > n-1 {
-		maxBits = n - 1
-	}
-
-	// Create information about each of the levels.
-	// A bogus "Level 0" whose sole purpose is so that
-	// level1.prev.needed==0.  This makes level1.nextPairFreq
-	// be a legitimate value that never gets chosen.
-	var levels [maxBitsLimit]levelInfo
-	// leafCounts[i] counts the number of literals at the left
-	// of ancestors of the rightmost node at level i.
-	// leafCounts[i][j] is the number of literals at the left
-	// of the level j ancestor.
-	var leafCounts [maxBitsLimit][maxBitsLimit]int32
-
-	for level := int32(1); level <= maxBits; level++ {
-		// For every level, the first two items are the first two characters.
-		// We initialize the levels as if we had already figured this out.
-		levels[level] = levelInfo{
-			level:        level,
-			lastFreq:     list[1].freq,
-			nextCharFreq: list[2].freq,
-			nextPairFreq: list[0].freq + list[1].freq,
-		}
-		leafCounts[level][level] = 2
-		if level == 1 {
-			levels[level].nextPairFreq = math.MaxInt32
-		}
-	}
-
-	// We need a total of 2*n - 2 items at top level and have already generated 2.
-	levels[maxBits].needed = 2*n - 4
-
-	level := maxBits
-	for {
-		l := &levels[level]
-		if l.nextPairFreq == math.MaxInt32 && l.nextCharFreq == math.MaxInt32 {
-			// We've run out of both leafs and pairs.
-			// End all calculations for this level.
-			// To make sure we never come back to this level or any lower level,
-			// set nextPairFreq impossibly large.
-			l.needed = 0
-			levels[level+1].nextPairFreq = math.MaxInt32
-			level++
-			continue
-		}
-
-		prevFreq := l.lastFreq
-		if l.nextCharFreq < l.nextPairFreq {
-			// The next item on this row is a leaf node.
-			n := leafCounts[level][level] + 1
-			l.lastFreq = l.nextCharFreq
-			// Lower leafCounts are the same of the previous node.
-			leafCounts[level][level] = n
-			l.nextCharFreq = list[n].freq
-		} else {
-			// The next item on this row is a pair from the previous row.
-			// nextPairFreq isn't valid until we generate two
-			// more values in the level below
-			l.lastFreq = l.nextPairFreq
-			// Take leaf counts from the lower level, except counts[level] remains the same.
-			copy(leafCounts[level][:level], leafCounts[level-1][:level])
-			levels[l.level-1].needed = 2
-		}
-
-		if l.needed--; l.needed == 0 {
-			// We've done everything we need to do for this level.
-			// Continue calculating one level up. Fill in nextPairFreq
-			// of that level with the sum of the two nodes we've just calculated on
-			// this level.
-			if l.level == maxBits {
-				// All done!
-				break
-			}
-			levels[l.level+1].nextPairFreq = prevFreq + l.lastFreq
-			level++
-		} else {
-			// If we stole from below, move down temporarily to replenish it.
-			for levels[level-1].needed > 0 {
-				level--
-			}
-		}
-	}
-
-	// Somethings is wrong if at the end, the top level is null or hasn't used
-	// all of the leaves.
-	if leafCounts[maxBits][maxBits] != n {
-		panic("leafCounts[maxBits][maxBits] != n")
-	}
-
-	bitCount := h.bitCount[:maxBits+1]
-	bits := 1
-	counts := &leafCounts[maxBits]
-	for level := maxBits; level > 0; level-- {
-		// chain.leafCount gives the number of literals requiring at least "bits"
-		// bits to encode.
-		bitCount[bits] = counts[level] - counts[level-1]
-		bits++
-	}
-	return bitCount
-}
-
-// Look at the leaves and assign them a bit count and an encoding as specified
-// in RFC 1951 3.2.2
-func (h *huffmanEncoder) assignEncodingAndSize(bitCount []int32, list []literalNode) {
-	code := uint16(0)
-	for n, bits := range bitCount {
-		code <<= 1
-		if n == 0 || bits == 0 {
-			continue
-		}
-		// The literals list[len(list)-bits] .. list[len(list)-bits]
-		// are encoded using "bits" bits, and get the values
-		// code, code + 1, ....  The code values are
-		// assigned in literal order (not frequency order).
-		chunk := list[len(list)-int(bits):]
-
-		h.lns.sort(chunk)
-		for _, node := range chunk {
-			h.codes[node.literal] = hcode{code: reverseBits(code, uint8(n)), len: uint16(n)}
-			code++
-		}
-		list = list[0 : len(list)-int(bits)]
-	}
-}
-
-// Update this Huffman Code object to be the minimum code for the specified frequency count.
-//
-// freq  An array of frequencies, in which frequency[i] gives the frequency of literal i.
-// maxBits  The maximum number of bits to use for any literal.
-func (h *huffmanEncoder) generate(freq []int32, maxBits int32) {
-	if h.freqcache == nil {
-		// Allocate a reusable buffer with the longest possible frequency table.
-		// Possible lengths are codegenCodeCount, offsetCodeCount and maxNumLit.
-		// The largest of these is maxNumLit, so we allocate for that case.
-		h.freqcache = make([]literalNode, maxNumLit+1)
-	}
-	list := h.freqcache[:len(freq)+1]
-	// Number of non-zero literals
-	count := 0
-	// Set list to be the set of all non-zero literals and their frequencies
-	for i, f := range freq {
-		if f != 0 {
-			list[count] = literalNode{uint16(i), f}
-			count++
-		} else {
-			list[count] = literalNode{}
-			h.codes[i].len = 0
-		}
-	}
-	list[len(freq)] = literalNode{}
-
-	list = list[:count]
-	if count <= 2 {
-		// Handle the small cases here, because they are awkward for the general case code. With
-		// two or fewer literals, everything has bit length 1.
-		for i, node := range list {
-			// "list" is in order of increasing literal value.
-			h.codes[node.literal].set(uint16(i), 1)
-		}
-		return
-	}
-	h.lfs.sort(list)
-
-	// Get the number of literals for each bit count
-	bitCount := h.bitCounts(list, maxBits)
-	// And do the assignment
-	h.assignEncodingAndSize(bitCount, list)
-}
-
-type byLiteral []literalNode
-
-func (s *byLiteral) sort(a []literalNode) {
-	*s = byLiteral(a)
-	sort.Sort(s)
-}
-
-func (s byLiteral) Len() int { return len(s) }
-
-func (s byLiteral) Less(i, j int) bool {
-	return s[i].literal < s[j].literal
-}
-
-func (s byLiteral) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
-
-type byFreq []literalNode
-
-func (s *byFreq) sort(a []literalNode) {
-	*s = byFreq(a)
-	sort.Sort(s)
-}
-
-func (s byFreq) Len() int { return len(s) }
-
-func (s byFreq) Less(i, j int) bool {
-	if s[i].freq == s[j].freq {
-		return s[i].literal < s[j].literal
-	}
-	return s[i].freq < s[j].freq
-}
-
-func (s byFreq) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
-
-func reverseBits(number uint16, bitLength byte) uint16 {
-	return bits.Reverse16(number << (16 - bitLength))
-}
diff --git a/contrib/go/_std_1.18/src/compress/gzip/gunzip.go b/contrib/go/_std_1.18/src/compress/gzip/gunzip.go
deleted file mode 100644
index 237b2b928b..0000000000
--- a/contrib/go/_std_1.18/src/compress/gzip/gunzip.go
+++ /dev/null
@@ -1,290 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package gzip implements reading and writing of gzip format compressed files,
-// as specified in RFC 1952.
-package gzip
-
-import (
-	"bufio"
-	"compress/flate"
-	"encoding/binary"
-	"errors"
-	"hash/crc32"
-	"io"
-	"time"
-)
-
-const (
-	gzipID1     = 0x1f
-	gzipID2     = 0x8b
-	gzipDeflate = 8
-	flagText    = 1 << 0
-	flagHdrCrc  = 1 << 1
-	flagExtra   = 1 << 2
-	flagName    = 1 << 3
-	flagComment = 1 << 4
-)
-
-var (
-	// ErrChecksum is returned when reading GZIP data that has an invalid checksum.
-	ErrChecksum = errors.New("gzip: invalid checksum")
-	// ErrHeader is returned when reading GZIP data that has an invalid header.
-	ErrHeader = errors.New("gzip: invalid header")
-)
-
-var le = binary.LittleEndian
-
-// noEOF converts io.EOF to io.ErrUnexpectedEOF.
-func noEOF(err error) error {
-	if err == io.EOF {
-		return io.ErrUnexpectedEOF
-	}
-	return err
-}
-
-// The gzip file stores a header giving metadata about the compressed file.
-// That header is exposed as the fields of the Writer and Reader structs.
-//
-// Strings must be UTF-8 encoded and may only contain Unicode code points
-// U+0001 through U+00FF, due to limitations of the GZIP file format.
-type Header struct {
-	Comment string    // comment
-	Extra   []byte    // "extra data"
-	ModTime time.Time // modification time
-	Name    string    // file name
-	OS      byte      // operating system type
-}
-
-// A Reader is an io.Reader that can be read to retrieve
-// uncompressed data from a gzip-format compressed file.
-//
-// In general, a gzip file can be a concatenation of gzip files,
-// each with its own header. Reads from the Reader
-// return the concatenation of the uncompressed data of each.
-// Only the first header is recorded in the Reader fields.
-//
-// Gzip files store a length and checksum of the uncompressed data.
-// The Reader will return an ErrChecksum when Read
-// reaches the end of the uncompressed data if it does not
-// have the expected length or checksum. Clients should treat data
-// returned by Read as tentative until they receive the io.EOF
-// marking the end of the data.
-type Reader struct {
-	Header       // valid after NewReader or Reader.Reset
-	r            flate.Reader
-	decompressor io.ReadCloser
-	digest       uint32 // CRC-32, IEEE polynomial (section 8)
-	size         uint32 // Uncompressed size (section 2.3.1)
-	buf          [512]byte
-	err          error
-	multistream  bool
-}
-
-// NewReader creates a new Reader reading the given reader.
-// If r does not also implement io.ByteReader,
-// the decompressor may read more data than necessary from r.
-//
-// It is the caller's responsibility to call Close on the Reader when done.
-//
-// The Reader.Header fields will be valid in the Reader returned.
-func NewReader(r io.Reader) (*Reader, error) {
-	z := new(Reader)
-	if err := z.Reset(r); err != nil {
-		return nil, err
-	}
-	return z, nil
-}
-
-// Reset discards the Reader z's state and makes it equivalent to the
-// result of its original state from NewReader, but reading from r instead.
-// This permits reusing a Reader rather than allocating a new one.
-func (z *Reader) Reset(r io.Reader) error {
-	*z = Reader{
-		decompressor: z.decompressor,
-		multistream:  true,
-	}
-	if rr, ok := r.(flate.Reader); ok {
-		z.r = rr
-	} else {
-		z.r = bufio.NewReader(r)
-	}
-	z.Header, z.err = z.readHeader()
-	return z.err
-}
-
-// Multistream controls whether the reader supports multistream files.
-//
-// If enabled (the default), the Reader expects the input to be a sequence
-// of individually gzipped data streams, each with its own header and
-// trailer, ending at EOF. The effect is that the concatenation of a sequence
-// of gzipped files is treated as equivalent to the gzip of the concatenation
-// of the sequence. This is standard behavior for gzip readers.
-//
-// Calling Multistream(false) disables this behavior; disabling the behavior
-// can be useful when reading file formats that distinguish individual gzip
-// data streams or mix gzip data streams with other data streams.
-// In this mode, when the Reader reaches the end of the data stream,
-// Read returns io.EOF. The underlying reader must implement io.ByteReader
-// in order to be left positioned just after the gzip stream.
-// To start the next stream, call z.Reset(r) followed by z.Multistream(false).
-// If there is no next stream, z.Reset(r) will return io.EOF.
-func (z *Reader) Multistream(ok bool) {
-	z.multistream = ok
-}
-
-// readString reads a NUL-terminated string from z.r.
-// It treats the bytes read as being encoded as ISO 8859-1 (Latin-1) and
-// will output a string encoded using UTF-8.
-// This method always updates z.digest with the data read.
-func (z *Reader) readString() (string, error) {
-	var err error
-	needConv := false
-	for i := 0; ; i++ {
-		if i >= len(z.buf) {
-			return "", ErrHeader
-		}
-		z.buf[i], err = z.r.ReadByte()
-		if err != nil {
-			return "", err
-		}
-		if z.buf[i] > 0x7f {
-			needConv = true
-		}
-		if z.buf[i] == 0 {
-			// Digest covers the NUL terminator.
-			z.digest = crc32.Update(z.digest, crc32.IEEETable, z.buf[:i+1])
-
-			// Strings are ISO 8859-1, Latin-1 (RFC 1952, section 2.3.1).
-			if needConv {
-				s := make([]rune, 0, i)
-				for _, v := range z.buf[:i] {
-					s = append(s, rune(v))
-				}
-				return string(s), nil
-			}
-			return string(z.buf[:i]), nil
-		}
-	}
-}
-
-// readHeader reads the GZIP header according to section 2.3.1.
-// This method does not set z.err.
-func (z *Reader) readHeader() (hdr Header, err error) {
-	if _, err = io.ReadFull(z.r, z.buf[:10]); err != nil {
-		// RFC 1952, section 2.2, says the following:
-		//	A gzip file consists of a series of "members" (compressed data sets).
-		//
-		// Other than this, the specification does not clarify whether a
-		// "series" is defined as "one or more" or "zero or more". To err on the
-		// side of caution, Go interprets this to mean "zero or more".
-		// Thus, it is okay to return io.EOF here.
-		return hdr, err
-	}
-	if z.buf[0] != gzipID1 || z.buf[1] != gzipID2 || z.buf[2] != gzipDeflate {
-		return hdr, ErrHeader
-	}
-	flg := z.buf[3]
-	if t := int64(le.Uint32(z.buf[4:8])); t > 0 {
-		// Section 2.3.1, the zero value for MTIME means that the
-		// modified time is not set.
-		hdr.ModTime = time.Unix(t, 0)
-	}
-	// z.buf[8] is XFL and is currently ignored.
-	hdr.OS = z.buf[9]
-	z.digest = crc32.ChecksumIEEE(z.buf[:10])
-
-	if flg&flagExtra != 0 {
-		if _, err = io.ReadFull(z.r, z.buf[:2]); err != nil {
-			return hdr, noEOF(err)
-		}
-		z.digest = crc32.Update(z.digest, crc32.IEEETable, z.buf[:2])
-		data := make([]byte, le.Uint16(z.buf[:2]))
-		if _, err = io.ReadFull(z.r, data); err != nil {
-			return hdr, noEOF(err)
-		}
-		z.digest = crc32.Update(z.digest, crc32.IEEETable, data)
-		hdr.Extra = data
-	}
-
-	var s string
-	if flg&flagName != 0 {
-		if s, err = z.readString(); err != nil {
-			return hdr, err
-		}
-		hdr.Name = s
-	}
-
-	if flg&flagComment != 0 {
-		if s, err = z.readString(); err != nil {
-			return hdr, err
-		}
-		hdr.Comment = s
-	}
-
-	if flg&flagHdrCrc != 0 {
-		if _, err = io.ReadFull(z.r, z.buf[:2]); err != nil {
-			return hdr, noEOF(err)
-		}
-		digest := le.Uint16(z.buf[:2])
-		if digest != uint16(z.digest) {
-			return hdr, ErrHeader
-		}
-	}
-
-	z.digest = 0
-	if z.decompressor == nil {
-		z.decompressor = flate.NewReader(z.r)
-	} else {
-		z.decompressor.(flate.Resetter).Reset(z.r, nil)
-	}
-	return hdr, nil
-}
-
-// Read implements io.Reader, reading uncompressed bytes from its underlying Reader.
-func (z *Reader) Read(p []byte) (n int, err error) {
-	if z.err != nil {
-		return 0, z.err
-	}
-
-	for n == 0 {
-		n, z.err = z.decompressor.Read(p)
-		z.digest = crc32.Update(z.digest, crc32.IEEETable, p[:n])
-		z.size += uint32(n)
-		if z.err != io.EOF {
-			// In the normal case we return here.
-			return n, z.err
-		}
-
-		// Finished file; check checksum and size.
-		if _, err := io.ReadFull(z.r, z.buf[:8]); err != nil {
-			z.err = noEOF(err)
-			return n, z.err
-		}
-		digest := le.Uint32(z.buf[:4])
-		size := le.Uint32(z.buf[4:8])
-		if digest != z.digest || size != z.size {
-			z.err = ErrChecksum
-			return n, z.err
-		}
-		z.digest, z.size = 0, 0
-
-		// File is ok; check if there is another.
-		if !z.multistream {
-			return n, io.EOF
-		}
-		z.err = nil // Remove io.EOF
-
-		if _, z.err = z.readHeader(); z.err != nil {
-			return n, z.err
-		}
-	}
-
-	return n, nil
-}
-
-// Close closes the Reader. It does not close the underlying io.Reader.
-// In order for the GZIP checksum to be verified, the reader must be
-// fully consumed until the io.EOF.
-func (z *Reader) Close() error { return z.decompressor.Close() }
diff --git a/contrib/go/_std_1.18/src/container/list/list.go b/contrib/go/_std_1.18/src/container/list/list.go
deleted file mode 100644
index 9555ad3900..0000000000
--- a/contrib/go/_std_1.18/src/container/list/list.go
+++ /dev/null
@@ -1,235 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package list implements a doubly linked list.
-//
-// To iterate over a list (where l is a *List):
-//	for e := l.Front(); e != nil; e = e.Next() {
-//		// do something with e.Value
-//	}
-//
-package list
-
-// Element is an element of a linked list.
-type Element struct {
-	// Next and previous pointers in the doubly-linked list of elements.
-	// To simplify the implementation, internally a list l is implemented
-	// as a ring, such that &l.root is both the next element of the last
-	// list element (l.Back()) and the previous element of the first list
-	// element (l.Front()).
-	next, prev *Element
-
-	// The list to which this element belongs.
-	list *List
-
-	// The value stored with this element.
-	Value any
-}
-
-// Next returns the next list element or nil.
-func (e *Element) Next() *Element {
-	if p := e.next; e.list != nil && p != &e.list.root {
-		return p
-	}
-	return nil
-}
-
-// Prev returns the previous list element or nil.
-func (e *Element) Prev() *Element {
-	if p := e.prev; e.list != nil && p != &e.list.root {
-		return p
-	}
-	return nil
-}
-
-// List represents a doubly linked list.
-// The zero value for List is an empty list ready to use.
-type List struct {
-	root Element // sentinel list element, only &root, root.prev, and root.next are used
-	len  int     // current list length excluding (this) sentinel element
-}
-
-// Init initializes or clears list l.
-func (l *List) Init() *List {
-	l.root.next = &l.root
-	l.root.prev = &l.root
-	l.len = 0
-	return l
-}
-
-// New returns an initialized list.
-func New() *List { return new(List).Init() }
-
-// Len returns the number of elements of list l.
-// The complexity is O(1).
-func (l *List) Len() int { return l.len }
-
-// Front returns the first element of list l or nil if the list is empty.
-func (l *List) Front() *Element {
-	if l.len == 0 {
-		return nil
-	}
-	return l.root.next
-}
-
-// Back returns the last element of list l or nil if the list is empty.
-func (l *List) Back() *Element {
-	if l.len == 0 {
-		return nil
-	}
-	return l.root.prev
-}
-
-// lazyInit lazily initializes a zero List value.
-func (l *List) lazyInit() {
-	if l.root.next == nil {
-		l.Init()
-	}
-}
-
-// insert inserts e after at, increments l.len, and returns e.
-func (l *List) insert(e, at *Element) *Element {
-	e.prev = at
-	e.next = at.next
-	e.prev.next = e
-	e.next.prev = e
-	e.list = l
-	l.len++
-	return e
-}
-
-// insertValue is a convenience wrapper for insert(&Element{Value: v}, at).
-func (l *List) insertValue(v any, at *Element) *Element {
-	return l.insert(&Element{Value: v}, at)
-}
-
-// remove removes e from its list, decrements l.len
-func (l *List) remove(e *Element) {
-	e.prev.next = e.next
-	e.next.prev = e.prev
-	e.next = nil // avoid memory leaks
-	e.prev = nil // avoid memory leaks
-	e.list = nil
-	l.len--
-}
-
-// move moves e to next to at.
-func (l *List) move(e, at *Element) {
-	if e == at {
-		return
-	}
-	e.prev.next = e.next
-	e.next.prev = e.prev
-
-	e.prev = at
-	e.next = at.next
-	e.prev.next = e
-	e.next.prev = e
-}
-
-// Remove removes e from l if e is an element of list l.
-// It returns the element value e.Value.
-// The element must not be nil.
-func (l *List) Remove(e *Element) any {
-	if e.list == l {
-		// if e.list == l, l must have been initialized when e was inserted
-		// in l or l == nil (e is a zero Element) and l.remove will crash
-		l.remove(e)
-	}
-	return e.Value
-}
-
-// PushFront inserts a new element e with value v at the front of list l and returns e.
-func (l *List) PushFront(v any) *Element {
-	l.lazyInit()
-	return l.insertValue(v, &l.root)
-}
-
-// PushBack inserts a new element e with value v at the back of list l and returns e.
-func (l *List) PushBack(v any) *Element {
-	l.lazyInit()
-	return l.insertValue(v, l.root.prev)
-}
-
-// InsertBefore inserts a new element e with value v immediately before mark and returns e.
-// If mark is not an element of l, the list is not modified.
-// The mark must not be nil.
-func (l *List) InsertBefore(v any, mark *Element) *Element {
-	if mark.list != l {
-		return nil
-	}
-	// see comment in List.Remove about initialization of l
-	return l.insertValue(v, mark.prev)
-}
-
-// InsertAfter inserts a new element e with value v immediately after mark and returns e.
-// If mark is not an element of l, the list is not modified.
-// The mark must not be nil.
-func (l *List) InsertAfter(v any, mark *Element) *Element {
-	if mark.list != l {
-		return nil
-	}
-	// see comment in List.Remove about initialization of l
-	return l.insertValue(v, mark)
-}
-
-// MoveToFront moves element e to the front of list l.
-// If e is not an element of l, the list is not modified.
-// The element must not be nil.
-func (l *List) MoveToFront(e *Element) {
-	if e.list != l || l.root.next == e {
-		return
-	}
-	// see comment in List.Remove about initialization of l
-	l.move(e, &l.root)
-}
-
-// MoveToBack moves element e to the back of list l.
-// If e is not an element of l, the list is not modified.
-// The element must not be nil.
-func (l *List) MoveToBack(e *Element) {
-	if e.list != l || l.root.prev == e {
-		return
-	}
-	// see comment in List.Remove about initialization of l
-	l.move(e, l.root.prev)
-}
-
-// MoveBefore moves element e to its new position before mark.
-// If e or mark is not an element of l, or e == mark, the list is not modified.
-// The element and mark must not be nil.
-func (l *List) MoveBefore(e, mark *Element) {
-	if e.list != l || e == mark || mark.list != l {
-		return
-	}
-	l.move(e, mark.prev)
-}
-
-// MoveAfter moves element e to its new position after mark.
-// If e or mark is not an element of l, or e == mark, the list is not modified.
-// The element and mark must not be nil.
-func (l *List) MoveAfter(e, mark *Element) {
-	if e.list != l || e == mark || mark.list != l {
-		return
-	}
-	l.move(e, mark)
-}
-
-// PushBackList inserts a copy of another list at the back of list l.
-// The lists l and other may be the same. They must not be nil.
-func (l *List) PushBackList(other *List) {
-	l.lazyInit()
-	for i, e := other.Len(), other.Front(); i > 0; i, e = i-1, e.Next() {
-		l.insertValue(e.Value, l.root.prev)
-	}
-}
-
-// PushFrontList inserts a copy of another list at the front of list l.
-// The lists l and other may be the same. They must not be nil.
-func (l *List) PushFrontList(other *List) {
-	l.lazyInit()
-	for i, e := other.Len(), other.Back(); i > 0; i, e = i-1, e.Prev() {
-		l.insertValue(e.Value, &l.root)
-	}
-}
diff --git a/contrib/go/_std_1.18/src/context/context.go b/contrib/go/_std_1.18/src/context/context.go
deleted file mode 100644
index cf010b2a69..0000000000
--- a/contrib/go/_std_1.18/src/context/context.go
+++ /dev/null
@@ -1,593 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package context defines the Context type, which carries deadlines,
-// cancellation signals, and other request-scoped values across API boundaries
-// and between processes.
-//
-// Incoming requests to a server should create a Context, and outgoing
-// calls to servers should accept a Context. The chain of function
-// calls between them must propagate the Context, optionally replacing
-// it with a derived Context created using WithCancel, WithDeadline,
-// WithTimeout, or WithValue. When a Context is canceled, all
-// Contexts derived from it are also canceled.
-//
-// The WithCancel, WithDeadline, and WithTimeout functions take a
-// Context (the parent) and return a derived Context (the child) and a
-// CancelFunc. Calling the CancelFunc cancels the child and its
-// children, removes the parent's reference to the child, and stops
-// any associated timers. Failing to call the CancelFunc leaks the
-// child and its children until the parent is canceled or the timer
-// fires. The go vet tool checks that CancelFuncs are used on all
-// control-flow paths.
-//
-// Programs that use Contexts should follow these rules to keep interfaces
-// consistent across packages and enable static analysis tools to check context
-// propagation:
-//
-// Do not store Contexts inside a struct type; instead, pass a Context
-// explicitly to each function that needs it. The Context should be the first
-// parameter, typically named ctx:
-//
-// 	func DoSomething(ctx context.Context, arg Arg) error {
-// 		// ... use ctx ...
-// 	}
-//
-// Do not pass a nil Context, even if a function permits it. Pass context.TODO
-// if you are unsure about which Context to use.
-//
-// Use context Values only for request-scoped data that transits processes and
-// APIs, not for passing optional parameters to functions.
-//
-// The same Context may be passed to functions running in different goroutines;
-// Contexts are safe for simultaneous use by multiple goroutines.
-//
-// See https://blog.golang.org/context for example code for a server that uses
-// Contexts.
-package context
-
-import (
-	"errors"
-	"internal/reflectlite"
-	"sync"
-	"sync/atomic"
-	"time"
-)
-
-// A Context carries a deadline, a cancellation signal, and other values across
-// API boundaries.
-//
-// Context's methods may be called by multiple goroutines simultaneously.
-type Context interface {
-	// Deadline returns the time when work done on behalf of this context
-	// should be canceled. Deadline returns ok==false when no deadline is
-	// set. Successive calls to Deadline return the same results.
-	Deadline() (deadline time.Time, ok bool)
-
-	// Done returns a channel that's closed when work done on behalf of this
-	// context should be canceled. Done may return nil if this context can
-	// never be canceled. Successive calls to Done return the same value.
-	// The close of the Done channel may happen asynchronously,
-	// after the cancel function returns.
-	//
-	// WithCancel arranges for Done to be closed when cancel is called;
-	// WithDeadline arranges for Done to be closed when the deadline
-	// expires; WithTimeout arranges for Done to be closed when the timeout
-	// elapses.
-	//
-	// Done is provided for use in select statements:
-	//
-	//  // Stream generates values with DoSomething and sends them to out
-	//  // until DoSomething returns an error or ctx.Done is closed.
-	//  func Stream(ctx context.Context, out chan<- Value) error {
-	//  	for {
-	//  		v, err := DoSomething(ctx)
-	//  		if err != nil {
-	//  			return err
-	//  		}
-	//  		select {
-	//  		case <-ctx.Done():
-	//  			return ctx.Err()
-	//  		case out <- v:
-	//  		}
-	//  	}
-	//  }
-	//
-	// See https://blog.golang.org/pipelines for more examples of how to use
-	// a Done channel for cancellation.
-	Done() <-chan struct{}
-
-	// If Done is not yet closed, Err returns nil.
-	// If Done is closed, Err returns a non-nil error explaining why:
-	// Canceled if the context was canceled
-	// or DeadlineExceeded if the context's deadline passed.
-	// After Err returns a non-nil error, successive calls to Err return the same error.
-	Err() error
-
-	// Value returns the value associated with this context for key, or nil
-	// if no value is associated with key. Successive calls to Value with
-	// the same key returns the same result.
-	//
-	// Use context values only for request-scoped data that transits
-	// processes and API boundaries, not for passing optional parameters to
-	// functions.
-	//
-	// A key identifies a specific value in a Context. Functions that wish
-	// to store values in Context typically allocate a key in a global
-	// variable then use that key as the argument to context.WithValue and
-	// Context.Value. A key can be any type that supports equality;
-	// packages should define keys as an unexported type to avoid
-	// collisions.
-	//
-	// Packages that define a Context key should provide type-safe accessors
-	// for the values stored using that key:
-	//
-	// 	// Package user defines a User type that's stored in Contexts.
-	// 	package user
-	//
-	// 	import "context"
-	//
-	// 	// User is the type of value stored in the Contexts.
-	// 	type User struct {...}
-	//
-	// 	// key is an unexported type for keys defined in this package.
-	// 	// This prevents collisions with keys defined in other packages.
-	// 	type key int
-	//
-	// 	// userKey is the key for user.User values in Contexts. It is
-	// 	// unexported; clients use user.NewContext and user.FromContext
-	// 	// instead of using this key directly.
-	// 	var userKey key
-	//
-	// 	// NewContext returns a new Context that carries value u.
-	// 	func NewContext(ctx context.Context, u *User) context.Context {
-	// 		return context.WithValue(ctx, userKey, u)
-	// 	}
-	//
-	// 	// FromContext returns the User value stored in ctx, if any.
-	// 	func FromContext(ctx context.Context) (*User, bool) {
-	// 		u, ok := ctx.Value(userKey).(*User)
-	// 		return u, ok
-	// 	}
-	Value(key any) any
-}
-
-// Canceled is the error returned by Context.Err when the context is canceled.
-var Canceled = errors.New("context canceled")
-
-// DeadlineExceeded is the error returned by Context.Err when the context's
-// deadline passes.
-var DeadlineExceeded error = deadlineExceededError{}
-
-type deadlineExceededError struct{}
-
-func (deadlineExceededError) Error() string   { return "context deadline exceeded" }
-func (deadlineExceededError) Timeout() bool   { return true }
-func (deadlineExceededError) Temporary() bool { return true }
-
-// An emptyCtx is never canceled, has no values, and has no deadline. It is not
-// struct{}, since vars of this type must have distinct addresses.
-type emptyCtx int
-
-func (*emptyCtx) Deadline() (deadline time.Time, ok bool) {
-	return
-}
-
-func (*emptyCtx) Done() <-chan struct{} {
-	return nil
-}
-
-func (*emptyCtx) Err() error {
-	return nil
-}
-
-func (*emptyCtx) Value(key any) any {
-	return nil
-}
-
-func (e *emptyCtx) String() string {
-	switch e {
-	case background:
-		return "context.Background"
-	case todo:
-		return "context.TODO"
-	}
-	return "unknown empty Context"
-}
-
-var (
-	background = new(emptyCtx)
-	todo       = new(emptyCtx)
-)
-
-// Background returns a non-nil, empty Context. It is never canceled, has no
-// values, and has no deadline. It is typically used by the main function,
-// initialization, and tests, and as the top-level Context for incoming
-// requests.
-func Background() Context {
-	return background
-}
-
-// TODO returns a non-nil, empty Context. Code should use context.TODO when
-// it's unclear which Context to use or it is not yet available (because the
-// surrounding function has not yet been extended to accept a Context
-// parameter).
-func TODO() Context {
-	return todo
-}
-
-// A CancelFunc tells an operation to abandon its work.
-// A CancelFunc does not wait for the work to stop.
-// A CancelFunc may be called by multiple goroutines simultaneously.
-// After the first call, subsequent calls to a CancelFunc do nothing.
-type CancelFunc func()
-
-// WithCancel returns a copy of parent with a new Done channel. The returned
-// context's Done channel is closed when the returned cancel function is called
-// or when the parent context's Done channel is closed, whichever happens first.
-//
-// Canceling this context releases resources associated with it, so code should
-// call cancel as soon as the operations running in this Context complete.
-func WithCancel(parent Context) (ctx Context, cancel CancelFunc) {
-	if parent == nil {
-		panic("cannot create context from nil parent")
-	}
-	c := newCancelCtx(parent)
-	propagateCancel(parent, &c)
-	return &c, func() { c.cancel(true, Canceled) }
-}
-
-// newCancelCtx returns an initialized cancelCtx.
-func newCancelCtx(parent Context) cancelCtx {
-	return cancelCtx{Context: parent}
-}
-
-// goroutines counts the number of goroutines ever created; for testing.
-var goroutines int32
-
-// propagateCancel arranges for child to be canceled when parent is.
-func propagateCancel(parent Context, child canceler) {
-	done := parent.Done()
-	if done == nil {
-		return // parent is never canceled
-	}
-
-	select {
-	case <-done:
-		// parent is already canceled
-		child.cancel(false, parent.Err())
-		return
-	default:
-	}
-
-	if p, ok := parentCancelCtx(parent); ok {
-		p.mu.Lock()
-		if p.err != nil {
-			// parent has already been canceled
-			child.cancel(false, p.err)
-		} else {
-			if p.children == nil {
-				p.children = make(map[canceler]struct{})
-			}
-			p.children[child] = struct{}{}
-		}
-		p.mu.Unlock()
-	} else {
-		atomic.AddInt32(&goroutines, +1)
-		go func() {
-			select {
-			case <-parent.Done():
-				child.cancel(false, parent.Err())
-			case <-child.Done():
-			}
-		}()
-	}
-}
-
-// &cancelCtxKey is the key that a cancelCtx returns itself for.
-var cancelCtxKey int
-
-// parentCancelCtx returns the underlying *cancelCtx for parent.
-// It does this by looking up parent.Value(&cancelCtxKey) to find
-// the innermost enclosing *cancelCtx and then checking whether
-// parent.Done() matches that *cancelCtx. (If not, the *cancelCtx
-// has been wrapped in a custom implementation providing a
-// different done channel, in which case we should not bypass it.)
-func parentCancelCtx(parent Context) (*cancelCtx, bool) {
-	done := parent.Done()
-	if done == closedchan || done == nil {
-		return nil, false
-	}
-	p, ok := parent.Value(&cancelCtxKey).(*cancelCtx)
-	if !ok {
-		return nil, false
-	}
-	pdone, _ := p.done.Load().(chan struct{})
-	if pdone != done {
-		return nil, false
-	}
-	return p, true
-}
-
-// removeChild removes a context from its parent.
-func removeChild(parent Context, child canceler) {
-	p, ok := parentCancelCtx(parent)
-	if !ok {
-		return
-	}
-	p.mu.Lock()
-	if p.children != nil {
-		delete(p.children, child)
-	}
-	p.mu.Unlock()
-}
-
-// A canceler is a context type that can be canceled directly. The
-// implementations are *cancelCtx and *timerCtx.
-type canceler interface {
-	cancel(removeFromParent bool, err error)
-	Done() <-chan struct{}
-}
-
-// closedchan is a reusable closed channel.
-var closedchan = make(chan struct{})
-
-func init() {
-	close(closedchan)
-}
-
-// A cancelCtx can be canceled. When canceled, it also cancels any children
-// that implement canceler.
-type cancelCtx struct {
-	Context
-
-	mu       sync.Mutex            // protects following fields
-	done     atomic.Value          // of chan struct{}, created lazily, closed by first cancel call
-	children map[canceler]struct{} // set to nil by the first cancel call
-	err      error                 // set to non-nil by the first cancel call
-}
-
-func (c *cancelCtx) Value(key any) any {
-	if key == &cancelCtxKey {
-		return c
-	}
-	return value(c.Context, key)
-}
-
-func (c *cancelCtx) Done() <-chan struct{} {
-	d := c.done.Load()
-	if d != nil {
-		return d.(chan struct{})
-	}
-	c.mu.Lock()
-	defer c.mu.Unlock()
-	d = c.done.Load()
-	if d == nil {
-		d = make(chan struct{})
-		c.done.Store(d)
-	}
-	return d.(chan struct{})
-}
-
-func (c *cancelCtx) Err() error {
-	c.mu.Lock()
-	err := c.err
-	c.mu.Unlock()
-	return err
-}
-
-type stringer interface {
-	String() string
-}
-
-func contextName(c Context) string {
-	if s, ok := c.(stringer); ok {
-		return s.String()
-	}
-	return reflectlite.TypeOf(c).String()
-}
-
-func (c *cancelCtx) String() string {
-	return contextName(c.Context) + ".WithCancel"
-}
-
-// cancel closes c.done, cancels each of c's children, and, if
-// removeFromParent is true, removes c from its parent's children.
-func (c *cancelCtx) cancel(removeFromParent bool, err error) {
-	if err == nil {
-		panic("context: internal error: missing cancel error")
-	}
-	c.mu.Lock()
-	if c.err != nil {
-		c.mu.Unlock()
-		return // already canceled
-	}
-	c.err = err
-	d, _ := c.done.Load().(chan struct{})
-	if d == nil {
-		c.done.Store(closedchan)
-	} else {
-		close(d)
-	}
-	for child := range c.children {
-		// NOTE: acquiring the child's lock while holding parent's lock.
-		child.cancel(false, err)
-	}
-	c.children = nil
-	c.mu.Unlock()
-
-	if removeFromParent {
-		removeChild(c.Context, c)
-	}
-}
-
-// WithDeadline returns a copy of the parent context with the deadline adjusted
-// to be no later than d. If the parent's deadline is already earlier than d,
-// WithDeadline(parent, d) is semantically equivalent to parent. The returned
-// context's Done channel is closed when the deadline expires, when the returned
-// cancel function is called, or when the parent context's Done channel is
-// closed, whichever happens first.
-//
-// Canceling this context releases resources associated with it, so code should
-// call cancel as soon as the operations running in this Context complete.
-func WithDeadline(parent Context, d time.Time) (Context, CancelFunc) {
-	if parent == nil {
-		panic("cannot create context from nil parent")
-	}
-	if cur, ok := parent.Deadline(); ok && cur.Before(d) {
-		// The current deadline is already sooner than the new one.
-		return WithCancel(parent)
-	}
-	c := &timerCtx{
-		cancelCtx: newCancelCtx(parent),
-		deadline:  d,
-	}
-	propagateCancel(parent, c)
-	dur := time.Until(d)
-	if dur <= 0 {
-		c.cancel(true, DeadlineExceeded) // deadline has already passed
-		return c, func() { c.cancel(false, Canceled) }
-	}
-	c.mu.Lock()
-	defer c.mu.Unlock()
-	if c.err == nil {
-		c.timer = time.AfterFunc(dur, func() {
-			c.cancel(true, DeadlineExceeded)
-		})
-	}
-	return c, func() { c.cancel(true, Canceled) }
-}
-
-// A timerCtx carries a timer and a deadline. It embeds a cancelCtx to
-// implement Done and Err. It implements cancel by stopping its timer then
-// delegating to cancelCtx.cancel.
-type timerCtx struct {
-	cancelCtx
-	timer *time.Timer // Under cancelCtx.mu.
-
-	deadline time.Time
-}
-
-func (c *timerCtx) Deadline() (deadline time.Time, ok bool) {
-	return c.deadline, true
-}
-
-func (c *timerCtx) String() string {
-	return contextName(c.cancelCtx.Context) + ".WithDeadline(" +
-		c.deadline.String() + " [" +
-		time.Until(c.deadline).String() + "])"
-}
-
-func (c *timerCtx) cancel(removeFromParent bool, err error) {
-	c.cancelCtx.cancel(false, err)
-	if removeFromParent {
-		// Remove this timerCtx from its parent cancelCtx's children.
-		removeChild(c.cancelCtx.Context, c)
-	}
-	c.mu.Lock()
-	if c.timer != nil {
-		c.timer.Stop()
-		c.timer = nil
-	}
-	c.mu.Unlock()
-}
-
-// WithTimeout returns WithDeadline(parent, time.Now().Add(timeout)).
-//
-// Canceling this context releases resources associated with it, so code should
-// call cancel as soon as the operations running in this Context complete:
-//
-// 	func slowOperationWithTimeout(ctx context.Context) (Result, error) {
-// 		ctx, cancel := context.WithTimeout(ctx, 100*time.Millisecond)
-// 		defer cancel()  // releases resources if slowOperation completes before timeout elapses
-// 		return slowOperation(ctx)
-// 	}
-func WithTimeout(parent Context, timeout time.Duration) (Context, CancelFunc) {
-	return WithDeadline(parent, time.Now().Add(timeout))
-}
-
-// WithValue returns a copy of parent in which the value associated with key is
-// val.
-//
-// Use context Values only for request-scoped data that transits processes and
-// APIs, not for passing optional parameters to functions.
-//
-// The provided key must be comparable and should not be of type
-// string or any other built-in type to avoid collisions between
-// packages using context. Users of WithValue should define their own
-// types for keys. To avoid allocating when assigning to an
-// interface{}, context keys often have concrete type
-// struct{}. Alternatively, exported context key variables' static
-// type should be a pointer or interface.
-func WithValue(parent Context, key, val any) Context {
-	if parent == nil {
-		panic("cannot create context from nil parent")
-	}
-	if key == nil {
-		panic("nil key")
-	}
-	if !reflectlite.TypeOf(key).Comparable() {
-		panic("key is not comparable")
-	}
-	return &valueCtx{parent, key, val}
-}
-
-// A valueCtx carries a key-value pair. It implements Value for that key and
-// delegates all other calls to the embedded Context.
-type valueCtx struct {
-	Context
-	key, val any
-}
-
-// stringify tries a bit to stringify v, without using fmt, since we don't
-// want context depending on the unicode tables. This is only used by
-// *valueCtx.String().
-func stringify(v any) string {
-	switch s := v.(type) {
-	case stringer:
-		return s.String()
-	case string:
-		return s
-	}
-	return "<not Stringer>"
-}
-
-func (c *valueCtx) String() string {
-	return contextName(c.Context) + ".WithValue(type " +
-		reflectlite.TypeOf(c.key).String() +
-		", val " + stringify(c.val) + ")"
-}
-
-func (c *valueCtx) Value(key any) any {
-	if c.key == key {
-		return c.val
-	}
-	return value(c.Context, key)
-}
-
-func value(c Context, key any) any {
-	for {
-		switch ctx := c.(type) {
-		case *valueCtx:
-			if key == ctx.key {
-				return ctx.val
-			}
-			c = ctx.Context
-		case *cancelCtx:
-			if key == &cancelCtxKey {
-				return c
-			}
-			c = ctx.Context
-		case *timerCtx:
-			if key == &cancelCtxKey {
-				return &ctx.cancelCtx
-			}
-			c = ctx.Context
-		case *emptyCtx:
-			return nil
-		default:
-			return c.Value(key)
-		}
-	}
-}
diff --git a/contrib/go/_std_1.18/src/crypto/aes/aes_gcm.go b/contrib/go/_std_1.18/src/crypto/aes/aes_gcm.go
deleted file mode 100644
index 98fb6d8e9b..0000000000
--- a/contrib/go/_std_1.18/src/crypto/aes/aes_gcm.go
+++ /dev/null
@@ -1,193 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build amd64 || arm64
-
-package aes
-
-import (
-	"crypto/cipher"
-	subtleoverlap "crypto/internal/subtle"
-	"crypto/subtle"
-	"errors"
-)
-
-// The following functions are defined in gcm_*.s.
-
-//go:noescape
-func gcmAesInit(productTable *[256]byte, ks []uint32)
-
-//go:noescape
-func gcmAesData(productTable *[256]byte, data []byte, T *[16]byte)
-
-//go:noescape
-func gcmAesEnc(productTable *[256]byte, dst, src []byte, ctr, T *[16]byte, ks []uint32)
-
-//go:noescape
-func gcmAesDec(productTable *[256]byte, dst, src []byte, ctr, T *[16]byte, ks []uint32)
-
-//go:noescape
-func gcmAesFinish(productTable *[256]byte, tagMask, T *[16]byte, pLen, dLen uint64)
-
-const (
-	gcmBlockSize         = 16
-	gcmTagSize           = 16
-	gcmMinimumTagSize    = 12 // NIST SP 800-38D recommends tags with 12 or more bytes.
-	gcmStandardNonceSize = 12
-)
-
-var errOpen = errors.New("cipher: message authentication failed")
-
-// aesCipherGCM implements crypto/cipher.gcmAble so that crypto/cipher.NewGCM
-// will use the optimised implementation in this file when possible. Instances
-// of this type only exist when hasGCMAsm returns true.
-type aesCipherGCM struct {
-	aesCipherAsm
-}
-
-// Assert that aesCipherGCM implements the gcmAble interface.
-var _ gcmAble = (*aesCipherGCM)(nil)
-
-// NewGCM returns the AES cipher wrapped in Galois Counter Mode. This is only
-// called by crypto/cipher.NewGCM via the gcmAble interface.
-func (c *aesCipherGCM) NewGCM(nonceSize, tagSize int) (cipher.AEAD, error) {
-	g := &gcmAsm{ks: c.enc, nonceSize: nonceSize, tagSize: tagSize}
-	gcmAesInit(&g.productTable, g.ks)
-	return g, nil
-}
-
-type gcmAsm struct {
-	// ks is the key schedule, the length of which depends on the size of
-	// the AES key.
-	ks []uint32
-	// productTable contains pre-computed multiples of the binary-field
-	// element used in GHASH.
-	productTable [256]byte
-	// nonceSize contains the expected size of the nonce, in bytes.
-	nonceSize int
-	// tagSize contains the size of the tag, in bytes.
-	tagSize int
-}
-
-func (g *gcmAsm) NonceSize() int {
-	return g.nonceSize
-}
-
-func (g *gcmAsm) Overhead() int {
-	return g.tagSize
-}
-
-// sliceForAppend takes a slice and a requested number of bytes. It returns a
-// slice with the contents of the given slice followed by that many bytes and a
-// second slice that aliases into it and contains only the extra bytes. If the
-// original slice has sufficient capacity then no allocation is performed.
-func sliceForAppend(in []byte, n int) (head, tail []byte) {
-	if total := len(in) + n; cap(in) >= total {
-		head = in[:total]
-	} else {
-		head = make([]byte, total)
-		copy(head, in)
-	}
-	tail = head[len(in):]
-	return
-}
-
-// Seal encrypts and authenticates plaintext. See the cipher.AEAD interface for
-// details.
-func (g *gcmAsm) Seal(dst, nonce, plaintext, data []byte) []byte {
-	if len(nonce) != g.nonceSize {
-		panic("crypto/cipher: incorrect nonce length given to GCM")
-	}
-	if uint64(len(plaintext)) > ((1<<32)-2)*BlockSize {
-		panic("crypto/cipher: message too large for GCM")
-	}
-
-	var counter, tagMask [gcmBlockSize]byte
-
-	if len(nonce) == gcmStandardNonceSize {
-		// Init counter to nonce||1
-		copy(counter[:], nonce)
-		counter[gcmBlockSize-1] = 1
-	} else {
-		// Otherwise counter = GHASH(nonce)
-		gcmAesData(&g.productTable, nonce, &counter)
-		gcmAesFinish(&g.productTable, &tagMask, &counter, uint64(len(nonce)), uint64(0))
-	}
-
-	encryptBlockAsm(len(g.ks)/4-1, &g.ks[0], &tagMask[0], &counter[0])
-
-	var tagOut [gcmTagSize]byte
-	gcmAesData(&g.productTable, data, &tagOut)
-
-	ret, out := sliceForAppend(dst, len(plaintext)+g.tagSize)
-	if subtleoverlap.InexactOverlap(out[:len(plaintext)], plaintext) {
-		panic("crypto/cipher: invalid buffer overlap")
-	}
-	if len(plaintext) > 0 {
-		gcmAesEnc(&g.productTable, out, plaintext, &counter, &tagOut, g.ks)
-	}
-	gcmAesFinish(&g.productTable, &tagMask, &tagOut, uint64(len(plaintext)), uint64(len(data)))
-	copy(out[len(plaintext):], tagOut[:])
-
-	return ret
-}
-
-// Open authenticates and decrypts ciphertext. See the cipher.AEAD interface
-// for details.
-func (g *gcmAsm) Open(dst, nonce, ciphertext, data []byte) ([]byte, error) {
-	if len(nonce) != g.nonceSize {
-		panic("crypto/cipher: incorrect nonce length given to GCM")
-	}
-	// Sanity check to prevent the authentication from always succeeding if an implementation
-	// leaves tagSize uninitialized, for example.
-	if g.tagSize < gcmMinimumTagSize {
-		panic("crypto/cipher: incorrect GCM tag size")
-	}
-
-	if len(ciphertext) < g.tagSize {
-		return nil, errOpen
-	}
-	if uint64(len(ciphertext)) > ((1<<32)-2)*uint64(BlockSize)+uint64(g.tagSize) {
-		return nil, errOpen
-	}
-
-	tag := ciphertext[len(ciphertext)-g.tagSize:]
-	ciphertext = ciphertext[:len(ciphertext)-g.tagSize]
-
-	// See GCM spec, section 7.1.
-	var counter, tagMask [gcmBlockSize]byte
-
-	if len(nonce) == gcmStandardNonceSize {
-		// Init counter to nonce||1
-		copy(counter[:], nonce)
-		counter[gcmBlockSize-1] = 1
-	} else {
-		// Otherwise counter = GHASH(nonce)
-		gcmAesData(&g.productTable, nonce, &counter)
-		gcmAesFinish(&g.productTable, &tagMask, &counter, uint64(len(nonce)), uint64(0))
-	}
-
-	encryptBlockAsm(len(g.ks)/4-1, &g.ks[0], &tagMask[0], &counter[0])
-
-	var expectedTag [gcmTagSize]byte
-	gcmAesData(&g.productTable, data, &expectedTag)
-
-	ret, out := sliceForAppend(dst, len(ciphertext))
-	if subtleoverlap.InexactOverlap(out, ciphertext) {
-		panic("crypto/cipher: invalid buffer overlap")
-	}
-	if len(ciphertext) > 0 {
-		gcmAesDec(&g.productTable, out, ciphertext, &counter, &expectedTag, g.ks)
-	}
-	gcmAesFinish(&g.productTable, &tagMask, &expectedTag, uint64(len(ciphertext)), uint64(len(data)))
-
-	if subtle.ConstantTimeCompare(expectedTag[:g.tagSize], tag) != 1 {
-		for i := range out {
-			out[i] = 0
-		}
-		return nil, errOpen
-	}
-
-	return ret, nil
-}
diff --git a/contrib/go/_std_1.18/src/crypto/aes/cipher.go b/contrib/go/_std_1.18/src/crypto/aes/cipher.go
deleted file mode 100644
index bb93fbb36e..0000000000
--- a/contrib/go/_std_1.18/src/crypto/aes/cipher.go
+++ /dev/null
@@ -1,78 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package aes
-
-import (
-	"crypto/cipher"
-	"crypto/internal/subtle"
-	"strconv"
-)
-
-// The AES block size in bytes.
-const BlockSize = 16
-
-// A cipher is an instance of AES encryption using a particular key.
-type aesCipher struct {
-	enc []uint32
-	dec []uint32
-}
-
-type KeySizeError int
-
-func (k KeySizeError) Error() string {
-	return "crypto/aes: invalid key size " + strconv.Itoa(int(k))
-}
-
-// NewCipher creates and returns a new cipher.Block.
-// The key argument should be the AES key,
-// either 16, 24, or 32 bytes to select
-// AES-128, AES-192, or AES-256.
-func NewCipher(key []byte) (cipher.Block, error) {
-	k := len(key)
-	switch k {
-	default:
-		return nil, KeySizeError(k)
-	case 16, 24, 32:
-		break
-	}
-	return newCipher(key)
-}
-
-// newCipherGeneric creates and returns a new cipher.Block
-// implemented in pure Go.
-func newCipherGeneric(key []byte) (cipher.Block, error) {
-	n := len(key) + 28
-	c := aesCipher{make([]uint32, n), make([]uint32, n)}
-	expandKeyGo(key, c.enc, c.dec)
-	return &c, nil
-}
-
-func (c *aesCipher) BlockSize() int { return BlockSize }
-
-func (c *aesCipher) Encrypt(dst, src []byte) {
-	if len(src) < BlockSize {
-		panic("crypto/aes: input not full block")
-	}
-	if len(dst) < BlockSize {
-		panic("crypto/aes: output not full block")
-	}
-	if subtle.InexactOverlap(dst[:BlockSize], src[:BlockSize]) {
-		panic("crypto/aes: invalid buffer overlap")
-	}
-	encryptBlockGo(c.enc, dst, src)
-}
-
-func (c *aesCipher) Decrypt(dst, src []byte) {
-	if len(src) < BlockSize {
-		panic("crypto/aes: input not full block")
-	}
-	if len(dst) < BlockSize {
-		panic("crypto/aes: output not full block")
-	}
-	if subtle.InexactOverlap(dst[:BlockSize], src[:BlockSize]) {
-		panic("crypto/aes: invalid buffer overlap")
-	}
-	decryptBlockGo(c.dec, dst, src)
-}
diff --git a/contrib/go/_std_1.18/src/crypto/aes/cipher_asm.go b/contrib/go/_std_1.18/src/crypto/aes/cipher_asm.go
deleted file mode 100644
index c948f1a579..0000000000
--- a/contrib/go/_std_1.18/src/crypto/aes/cipher_asm.go
+++ /dev/null
@@ -1,99 +0,0 @@
-// Copyright 2012 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build amd64 || arm64
-
-package aes
-
-import (
-	"crypto/cipher"
-	"crypto/internal/subtle"
-	"internal/cpu"
-)
-
-// defined in asm_*.s
-
-//go:noescape
-func encryptBlockAsm(nr int, xk *uint32, dst, src *byte)
-
-//go:noescape
-func decryptBlockAsm(nr int, xk *uint32, dst, src *byte)
-
-//go:noescape
-func expandKeyAsm(nr int, key *byte, enc *uint32, dec *uint32)
-
-type aesCipherAsm struct {
-	aesCipher
-}
-
-var supportsAES = cpu.X86.HasAES || cpu.ARM64.HasAES
-var supportsGFMUL = cpu.X86.HasPCLMULQDQ || cpu.ARM64.HasPMULL
-
-func newCipher(key []byte) (cipher.Block, error) {
-	if !supportsAES {
-		return newCipherGeneric(key)
-	}
-	n := len(key) + 28
-	c := aesCipherAsm{aesCipher{make([]uint32, n), make([]uint32, n)}}
-	var rounds int
-	switch len(key) {
-	case 128 / 8:
-		rounds = 10
-	case 192 / 8:
-		rounds = 12
-	case 256 / 8:
-		rounds = 14
-	}
-
-	expandKeyAsm(rounds, &key[0], &c.enc[0], &c.dec[0])
-	if supportsAES && supportsGFMUL {
-		return &aesCipherGCM{c}, nil
-	}
-	return &c, nil
-}
-
-func (c *aesCipherAsm) BlockSize() int { return BlockSize }
-
-func (c *aesCipherAsm) Encrypt(dst, src []byte) {
-	if len(src) < BlockSize {
-		panic("crypto/aes: input not full block")
-	}
-	if len(dst) < BlockSize {
-		panic("crypto/aes: output not full block")
-	}
-	if subtle.InexactOverlap(dst[:BlockSize], src[:BlockSize]) {
-		panic("crypto/aes: invalid buffer overlap")
-	}
-	encryptBlockAsm(len(c.enc)/4-1, &c.enc[0], &dst[0], &src[0])
-}
-
-func (c *aesCipherAsm) Decrypt(dst, src []byte) {
-	if len(src) < BlockSize {
-		panic("crypto/aes: input not full block")
-	}
-	if len(dst) < BlockSize {
-		panic("crypto/aes: output not full block")
-	}
-	if subtle.InexactOverlap(dst[:BlockSize], src[:BlockSize]) {
-		panic("crypto/aes: invalid buffer overlap")
-	}
-	decryptBlockAsm(len(c.dec)/4-1, &c.dec[0], &dst[0], &src[0])
-}
-
-// expandKey is used by BenchmarkExpand to ensure that the asm implementation
-// of key expansion is used for the benchmark when it is available.
-func expandKey(key []byte, enc, dec []uint32) {
-	if supportsAES {
-		rounds := 10 // rounds needed for AES128
-		switch len(key) {
-		case 192 / 8:
-			rounds = 12
-		case 256 / 8:
-			rounds = 14
-		}
-		expandKeyAsm(rounds, &key[0], &enc[0], &dec[0])
-	} else {
-		expandKeyGo(key, enc, dec)
-	}
-}
diff --git a/contrib/go/_std_1.18/src/crypto/cipher/cbc.go b/contrib/go/_std_1.18/src/crypto/cipher/cbc.go
deleted file mode 100644
index 0d07192e29..0000000000
--- a/contrib/go/_std_1.18/src/crypto/cipher/cbc.go
+++ /dev/null
@@ -1,163 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Cipher block chaining (CBC) mode.
-
-// CBC provides confidentiality by xoring (chaining) each plaintext block
-// with the previous ciphertext block before applying the block cipher.
-
-// See NIST SP 800-38A, pp 10-11
-
-package cipher
-
-import "crypto/internal/subtle"
-
-type cbc struct {
-	b         Block
-	blockSize int
-	iv        []byte
-	tmp       []byte
-}
-
-func newCBC(b Block, iv []byte) *cbc {
-	return &cbc{
-		b:         b,
-		blockSize: b.BlockSize(),
-		iv:        dup(iv),
-		tmp:       make([]byte, b.BlockSize()),
-	}
-}
-
-type cbcEncrypter cbc
-
-// cbcEncAble is an interface implemented by ciphers that have a specific
-// optimized implementation of CBC encryption, like crypto/aes.
-// NewCBCEncrypter will check for this interface and return the specific
-// BlockMode if found.
-type cbcEncAble interface {
-	NewCBCEncrypter(iv []byte) BlockMode
-}
-
-// NewCBCEncrypter returns a BlockMode which encrypts in cipher block chaining
-// mode, using the given Block. The length of iv must be the same as the
-// Block's block size.
-func NewCBCEncrypter(b Block, iv []byte) BlockMode {
-	if len(iv) != b.BlockSize() {
-		panic("cipher.NewCBCEncrypter: IV length must equal block size")
-	}
-	if cbc, ok := b.(cbcEncAble); ok {
-		return cbc.NewCBCEncrypter(iv)
-	}
-	return (*cbcEncrypter)(newCBC(b, iv))
-}
-
-func (x *cbcEncrypter) BlockSize() int { return x.blockSize }
-
-func (x *cbcEncrypter) CryptBlocks(dst, src []byte) {
-	if len(src)%x.blockSize != 0 {
-		panic("crypto/cipher: input not full blocks")
-	}
-	if len(dst) < len(src) {
-		panic("crypto/cipher: output smaller than input")
-	}
-	if subtle.InexactOverlap(dst[:len(src)], src) {
-		panic("crypto/cipher: invalid buffer overlap")
-	}
-
-	iv := x.iv
-
-	for len(src) > 0 {
-		// Write the xor to dst, then encrypt in place.
-		xorBytes(dst[:x.blockSize], src[:x.blockSize], iv)
-		x.b.Encrypt(dst[:x.blockSize], dst[:x.blockSize])
-
-		// Move to the next block with this block as the next iv.
-		iv = dst[:x.blockSize]
-		src = src[x.blockSize:]
-		dst = dst[x.blockSize:]
-	}
-
-	// Save the iv for the next CryptBlocks call.
-	copy(x.iv, iv)
-}
-
-func (x *cbcEncrypter) SetIV(iv []byte) {
-	if len(iv) != len(x.iv) {
-		panic("cipher: incorrect length IV")
-	}
-	copy(x.iv, iv)
-}
-
-type cbcDecrypter cbc
-
-// cbcDecAble is an interface implemented by ciphers that have a specific
-// optimized implementation of CBC decryption, like crypto/aes.
-// NewCBCDecrypter will check for this interface and return the specific
-// BlockMode if found.
-type cbcDecAble interface {
-	NewCBCDecrypter(iv []byte) BlockMode
-}
-
-// NewCBCDecrypter returns a BlockMode which decrypts in cipher block chaining
-// mode, using the given Block. The length of iv must be the same as the
-// Block's block size and must match the iv used to encrypt the data.
-func NewCBCDecrypter(b Block, iv []byte) BlockMode {
-	if len(iv) != b.BlockSize() {
-		panic("cipher.NewCBCDecrypter: IV length must equal block size")
-	}
-	if cbc, ok := b.(cbcDecAble); ok {
-		return cbc.NewCBCDecrypter(iv)
-	}
-	return (*cbcDecrypter)(newCBC(b, iv))
-}
-
-func (x *cbcDecrypter) BlockSize() int { return x.blockSize }
-
-func (x *cbcDecrypter) CryptBlocks(dst, src []byte) {
-	if len(src)%x.blockSize != 0 {
-		panic("crypto/cipher: input not full blocks")
-	}
-	if len(dst) < len(src) {
-		panic("crypto/cipher: output smaller than input")
-	}
-	if subtle.InexactOverlap(dst[:len(src)], src) {
-		panic("crypto/cipher: invalid buffer overlap")
-	}
-	if len(src) == 0 {
-		return
-	}
-
-	// For each block, we need to xor the decrypted data with the previous block's ciphertext (the iv).
-	// To avoid making a copy each time, we loop over the blocks BACKWARDS.
-	end := len(src)
-	start := end - x.blockSize
-	prev := start - x.blockSize
-
-	// Copy the last block of ciphertext in preparation as the new iv.
-	copy(x.tmp, src[start:end])
-
-	// Loop over all but the first block.
-	for start > 0 {
-		x.b.Decrypt(dst[start:end], src[start:end])
-		xorBytes(dst[start:end], dst[start:end], src[prev:start])
-
-		end = start
-		start = prev
-		prev -= x.blockSize
-	}
-
-	// The first block is special because it uses the saved iv.
-	x.b.Decrypt(dst[start:end], src[start:end])
-	xorBytes(dst[start:end], dst[start:end], x.iv)
-
-	// Set the new iv to the first block we copied earlier.
-	x.iv, x.tmp = x.tmp, x.iv
-}
-
-func (x *cbcDecrypter) SetIV(iv []byte) {
-	if len(iv) != len(x.iv) {
-		panic("cipher: incorrect length IV")
-	}
-	copy(x.iv, iv)
-}
diff --git a/contrib/go/_std_1.18/src/crypto/cipher/gcm.go b/contrib/go/_std_1.18/src/crypto/cipher/gcm.go
deleted file mode 100644
index ba0af84a9d..0000000000
--- a/contrib/go/_std_1.18/src/crypto/cipher/gcm.go
+++ /dev/null
@@ -1,426 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cipher
-
-import (
-	subtleoverlap "crypto/internal/subtle"
-	"crypto/subtle"
-	"encoding/binary"
-	"errors"
-)
-
-// AEAD is a cipher mode providing authenticated encryption with associated
-// data. For a description of the methodology, see
-//	https://en.wikipedia.org/wiki/Authenticated_encryption
-type AEAD interface {
-	// NonceSize returns the size of the nonce that must be passed to Seal
-	// and Open.
-	NonceSize() int
-
-	// Overhead returns the maximum difference between the lengths of a
-	// plaintext and its ciphertext.
-	Overhead() int
-
-	// Seal encrypts and authenticates plaintext, authenticates the
-	// additional data and appends the result to dst, returning the updated
-	// slice. The nonce must be NonceSize() bytes long and unique for all
-	// time, for a given key.
-	//
-	// To reuse plaintext's storage for the encrypted output, use plaintext[:0]
-	// as dst. Otherwise, the remaining capacity of dst must not overlap plaintext.
-	Seal(dst, nonce, plaintext, additionalData []byte) []byte
-
-	// Open decrypts and authenticates ciphertext, authenticates the
-	// additional data and, if successful, appends the resulting plaintext
-	// to dst, returning the updated slice. The nonce must be NonceSize()
-	// bytes long and both it and the additional data must match the
-	// value passed to Seal.
-	//
-	// To reuse ciphertext's storage for the decrypted output, use ciphertext[:0]
-	// as dst. Otherwise, the remaining capacity of dst must not overlap plaintext.
-	//
-	// Even if the function fails, the contents of dst, up to its capacity,
-	// may be overwritten.
-	Open(dst, nonce, ciphertext, additionalData []byte) ([]byte, error)
-}
-
-// gcmAble is an interface implemented by ciphers that have a specific optimized
-// implementation of GCM, like crypto/aes. NewGCM will check for this interface
-// and return the specific AEAD if found.
-type gcmAble interface {
-	NewGCM(nonceSize, tagSize int) (AEAD, error)
-}
-
-// gcmFieldElement represents a value in GF(2¹²⁸). In order to reflect the GCM
-// standard and make binary.BigEndian suitable for marshaling these values, the
-// bits are stored in big endian order. For example:
-//   the coefficient of x⁰ can be obtained by v.low >> 63.
-//   the coefficient of x⁶³ can be obtained by v.low & 1.
-//   the coefficient of x⁶⁴ can be obtained by v.high >> 63.
-//   the coefficient of x¹²⁷ can be obtained by v.high & 1.
-type gcmFieldElement struct {
-	low, high uint64
-}
-
-// gcm represents a Galois Counter Mode with a specific key. See
-// https://csrc.nist.gov/groups/ST/toolkit/BCM/documents/proposedmodes/gcm/gcm-revised-spec.pdf
-type gcm struct {
-	cipher    Block
-	nonceSize int
-	tagSize   int
-	// productTable contains the first sixteen powers of the key, H.
-	// However, they are in bit reversed order. See NewGCMWithNonceSize.
-	productTable [16]gcmFieldElement
-}
-
-// NewGCM returns the given 128-bit, block cipher wrapped in Galois Counter Mode
-// with the standard nonce length.
-//
-// In general, the GHASH operation performed by this implementation of GCM is not constant-time.
-// An exception is when the underlying Block was created by aes.NewCipher
-// on systems with hardware support for AES. See the crypto/aes package documentation for details.
-func NewGCM(cipher Block) (AEAD, error) {
-	return newGCMWithNonceAndTagSize(cipher, gcmStandardNonceSize, gcmTagSize)
-}
-
-// NewGCMWithNonceSize returns the given 128-bit, block cipher wrapped in Galois
-// Counter Mode, which accepts nonces of the given length. The length must not
-// be zero.
-//
-// Only use this function if you require compatibility with an existing
-// cryptosystem that uses non-standard nonce lengths. All other users should use
-// NewGCM, which is faster and more resistant to misuse.
-func NewGCMWithNonceSize(cipher Block, size int) (AEAD, error) {
-	return newGCMWithNonceAndTagSize(cipher, size, gcmTagSize)
-}
-
-// NewGCMWithTagSize returns the given 128-bit, block cipher wrapped in Galois
-// Counter Mode, which generates tags with the given length.
-//
-// Tag sizes between 12 and 16 bytes are allowed.
-//
-// Only use this function if you require compatibility with an existing
-// cryptosystem that uses non-standard tag lengths. All other users should use
-// NewGCM, which is more resistant to misuse.
-func NewGCMWithTagSize(cipher Block, tagSize int) (AEAD, error) {
-	return newGCMWithNonceAndTagSize(cipher, gcmStandardNonceSize, tagSize)
-}
-
-func newGCMWithNonceAndTagSize(cipher Block, nonceSize, tagSize int) (AEAD, error) {
-	if tagSize < gcmMinimumTagSize || tagSize > gcmBlockSize {
-		return nil, errors.New("cipher: incorrect tag size given to GCM")
-	}
-
-	if nonceSize <= 0 {
-		return nil, errors.New("cipher: the nonce can't have zero length, or the security of the key will be immediately compromised")
-	}
-
-	if cipher, ok := cipher.(gcmAble); ok {
-		return cipher.NewGCM(nonceSize, tagSize)
-	}
-
-	if cipher.BlockSize() != gcmBlockSize {
-		return nil, errors.New("cipher: NewGCM requires 128-bit block cipher")
-	}
-
-	var key [gcmBlockSize]byte
-	cipher.Encrypt(key[:], key[:])
-
-	g := &gcm{cipher: cipher, nonceSize: nonceSize, tagSize: tagSize}
-
-	// We precompute 16 multiples of |key|. However, when we do lookups
-	// into this table we'll be using bits from a field element and
-	// therefore the bits will be in the reverse order. So normally one
-	// would expect, say, 4*key to be in index 4 of the table but due to
-	// this bit ordering it will actually be in index 0010 (base 2) = 2.
-	x := gcmFieldElement{
-		binary.BigEndian.Uint64(key[:8]),
-		binary.BigEndian.Uint64(key[8:]),
-	}
-	g.productTable[reverseBits(1)] = x
-
-	for i := 2; i < 16; i += 2 {
-		g.productTable[reverseBits(i)] = gcmDouble(&g.productTable[reverseBits(i/2)])
-		g.productTable[reverseBits(i+1)] = gcmAdd(&g.productTable[reverseBits(i)], &x)
-	}
-
-	return g, nil
-}
-
-const (
-	gcmBlockSize         = 16
-	gcmTagSize           = 16
-	gcmMinimumTagSize    = 12 // NIST SP 800-38D recommends tags with 12 or more bytes.
-	gcmStandardNonceSize = 12
-)
-
-func (g *gcm) NonceSize() int {
-	return g.nonceSize
-}
-
-func (g *gcm) Overhead() int {
-	return g.tagSize
-}
-
-func (g *gcm) Seal(dst, nonce, plaintext, data []byte) []byte {
-	if len(nonce) != g.nonceSize {
-		panic("crypto/cipher: incorrect nonce length given to GCM")
-	}
-	if uint64(len(plaintext)) > ((1<<32)-2)*uint64(g.cipher.BlockSize()) {
-		panic("crypto/cipher: message too large for GCM")
-	}
-
-	ret, out := sliceForAppend(dst, len(plaintext)+g.tagSize)
-	if subtleoverlap.InexactOverlap(out, plaintext) {
-		panic("crypto/cipher: invalid buffer overlap")
-	}
-
-	var counter, tagMask [gcmBlockSize]byte
-	g.deriveCounter(&counter, nonce)
-
-	g.cipher.Encrypt(tagMask[:], counter[:])
-	gcmInc32(&counter)
-
-	g.counterCrypt(out, plaintext, &counter)
-
-	var tag [gcmTagSize]byte
-	g.auth(tag[:], out[:len(plaintext)], data, &tagMask)
-	copy(out[len(plaintext):], tag[:])
-
-	return ret
-}
-
-var errOpen = errors.New("cipher: message authentication failed")
-
-func (g *gcm) Open(dst, nonce, ciphertext, data []byte) ([]byte, error) {
-	if len(nonce) != g.nonceSize {
-		panic("crypto/cipher: incorrect nonce length given to GCM")
-	}
-	// Sanity check to prevent the authentication from always succeeding if an implementation
-	// leaves tagSize uninitialized, for example.
-	if g.tagSize < gcmMinimumTagSize {
-		panic("crypto/cipher: incorrect GCM tag size")
-	}
-
-	if len(ciphertext) < g.tagSize {
-		return nil, errOpen
-	}
-	if uint64(len(ciphertext)) > ((1<<32)-2)*uint64(g.cipher.BlockSize())+uint64(g.tagSize) {
-		return nil, errOpen
-	}
-
-	tag := ciphertext[len(ciphertext)-g.tagSize:]
-	ciphertext = ciphertext[:len(ciphertext)-g.tagSize]
-
-	var counter, tagMask [gcmBlockSize]byte
-	g.deriveCounter(&counter, nonce)
-
-	g.cipher.Encrypt(tagMask[:], counter[:])
-	gcmInc32(&counter)
-
-	var expectedTag [gcmTagSize]byte
-	g.auth(expectedTag[:], ciphertext, data, &tagMask)
-
-	ret, out := sliceForAppend(dst, len(ciphertext))
-	if subtleoverlap.InexactOverlap(out, ciphertext) {
-		panic("crypto/cipher: invalid buffer overlap")
-	}
-
-	if subtle.ConstantTimeCompare(expectedTag[:g.tagSize], tag) != 1 {
-		// The AESNI code decrypts and authenticates concurrently, and
-		// so overwrites dst in the event of a tag mismatch. That
-		// behavior is mimicked here in order to be consistent across
-		// platforms.
-		for i := range out {
-			out[i] = 0
-		}
-		return nil, errOpen
-	}
-
-	g.counterCrypt(out, ciphertext, &counter)
-
-	return ret, nil
-}
-
-// reverseBits reverses the order of the bits of 4-bit number in i.
-func reverseBits(i int) int {
-	i = ((i << 2) & 0xc) | ((i >> 2) & 0x3)
-	i = ((i << 1) & 0xa) | ((i >> 1) & 0x5)
-	return i
-}
-
-// gcmAdd adds two elements of GF(2¹²⁸) and returns the sum.
-func gcmAdd(x, y *gcmFieldElement) gcmFieldElement {
-	// Addition in a characteristic 2 field is just XOR.
-	return gcmFieldElement{x.low ^ y.low, x.high ^ y.high}
-}
-
-// gcmDouble returns the result of doubling an element of GF(2¹²⁸).
-func gcmDouble(x *gcmFieldElement) (double gcmFieldElement) {
-	msbSet := x.high&1 == 1
-
-	// Because of the bit-ordering, doubling is actually a right shift.
-	double.high = x.high >> 1
-	double.high |= x.low << 63
-	double.low = x.low >> 1
-
-	// If the most-significant bit was set before shifting then it,
-	// conceptually, becomes a term of x^128. This is greater than the
-	// irreducible polynomial so the result has to be reduced. The
-	// irreducible polynomial is 1+x+x^2+x^7+x^128. We can subtract that to
-	// eliminate the term at x^128 which also means subtracting the other
-	// four terms. In characteristic 2 fields, subtraction == addition ==
-	// XOR.
-	if msbSet {
-		double.low ^= 0xe100000000000000
-	}
-
-	return
-}
-
-var gcmReductionTable = []uint16{
-	0x0000, 0x1c20, 0x3840, 0x2460, 0x7080, 0x6ca0, 0x48c0, 0x54e0,
-	0xe100, 0xfd20, 0xd940, 0xc560, 0x9180, 0x8da0, 0xa9c0, 0xb5e0,
-}
-
-// mul sets y to y*H, where H is the GCM key, fixed during NewGCMWithNonceSize.
-func (g *gcm) mul(y *gcmFieldElement) {
-	var z gcmFieldElement
-
-	for i := 0; i < 2; i++ {
-		word := y.high
-		if i == 1 {
-			word = y.low
-		}
-
-		// Multiplication works by multiplying z by 16 and adding in
-		// one of the precomputed multiples of H.
-		for j := 0; j < 64; j += 4 {
-			msw := z.high & 0xf
-			z.high >>= 4
-			z.high |= z.low << 60
-			z.low >>= 4
-			z.low ^= uint64(gcmReductionTable[msw]) << 48
-
-			// the values in |table| are ordered for
-			// little-endian bit positions. See the comment
-			// in NewGCMWithNonceSize.
-			t := &g.productTable[word&0xf]
-
-			z.low ^= t.low
-			z.high ^= t.high
-			word >>= 4
-		}
-	}
-
-	*y = z
-}
-
-// updateBlocks extends y with more polynomial terms from blocks, based on
-// Horner's rule. There must be a multiple of gcmBlockSize bytes in blocks.
-func (g *gcm) updateBlocks(y *gcmFieldElement, blocks []byte) {
-	for len(blocks) > 0 {
-		y.low ^= binary.BigEndian.Uint64(blocks)
-		y.high ^= binary.BigEndian.Uint64(blocks[8:])
-		g.mul(y)
-		blocks = blocks[gcmBlockSize:]
-	}
-}
-
-// update extends y with more polynomial terms from data. If data is not a
-// multiple of gcmBlockSize bytes long then the remainder is zero padded.
-func (g *gcm) update(y *gcmFieldElement, data []byte) {
-	fullBlocks := (len(data) >> 4) << 4
-	g.updateBlocks(y, data[:fullBlocks])
-
-	if len(data) != fullBlocks {
-		var partialBlock [gcmBlockSize]byte
-		copy(partialBlock[:], data[fullBlocks:])
-		g.updateBlocks(y, partialBlock[:])
-	}
-}
-
-// gcmInc32 treats the final four bytes of counterBlock as a big-endian value
-// and increments it.
-func gcmInc32(counterBlock *[16]byte) {
-	ctr := counterBlock[len(counterBlock)-4:]
-	binary.BigEndian.PutUint32(ctr, binary.BigEndian.Uint32(ctr)+1)
-}
-
-// sliceForAppend takes a slice and a requested number of bytes. It returns a
-// slice with the contents of the given slice followed by that many bytes and a
-// second slice that aliases into it and contains only the extra bytes. If the
-// original slice has sufficient capacity then no allocation is performed.
-func sliceForAppend(in []byte, n int) (head, tail []byte) {
-	if total := len(in) + n; cap(in) >= total {
-		head = in[:total]
-	} else {
-		head = make([]byte, total)
-		copy(head, in)
-	}
-	tail = head[len(in):]
-	return
-}
-
-// counterCrypt crypts in to out using g.cipher in counter mode.
-func (g *gcm) counterCrypt(out, in []byte, counter *[gcmBlockSize]byte) {
-	var mask [gcmBlockSize]byte
-
-	for len(in) >= gcmBlockSize {
-		g.cipher.Encrypt(mask[:], counter[:])
-		gcmInc32(counter)
-
-		xorWords(out, in, mask[:])
-		out = out[gcmBlockSize:]
-		in = in[gcmBlockSize:]
-	}
-
-	if len(in) > 0 {
-		g.cipher.Encrypt(mask[:], counter[:])
-		gcmInc32(counter)
-		xorBytes(out, in, mask[:])
-	}
-}
-
-// deriveCounter computes the initial GCM counter state from the given nonce.
-// See NIST SP 800-38D, section 7.1. This assumes that counter is filled with
-// zeros on entry.
-func (g *gcm) deriveCounter(counter *[gcmBlockSize]byte, nonce []byte) {
-	// GCM has two modes of operation with respect to the initial counter
-	// state: a "fast path" for 96-bit (12-byte) nonces, and a "slow path"
-	// for nonces of other lengths. For a 96-bit nonce, the nonce, along
-	// with a four-byte big-endian counter starting at one, is used
-	// directly as the starting counter. For other nonce sizes, the counter
-	// is computed by passing it through the GHASH function.
-	if len(nonce) == gcmStandardNonceSize {
-		copy(counter[:], nonce)
-		counter[gcmBlockSize-1] = 1
-	} else {
-		var y gcmFieldElement
-		g.update(&y, nonce)
-		y.high ^= uint64(len(nonce)) * 8
-		g.mul(&y)
-		binary.BigEndian.PutUint64(counter[:8], y.low)
-		binary.BigEndian.PutUint64(counter[8:], y.high)
-	}
-}
-
-// auth calculates GHASH(ciphertext, additionalData), masks the result with
-// tagMask and writes the result to out.
-func (g *gcm) auth(out, ciphertext, additionalData []byte, tagMask *[gcmTagSize]byte) {
-	var y gcmFieldElement
-	g.update(&y, additionalData)
-	g.update(&y, ciphertext)
-
-	y.low ^= uint64(len(additionalData)) * 8
-	y.high ^= uint64(len(ciphertext)) * 8
-
-	g.mul(&y)
-
-	binary.BigEndian.PutUint64(out, y.low)
-	binary.BigEndian.PutUint64(out[8:], y.high)
-
-	xorWords(out, out, tagMask[:])
-}
diff --git a/contrib/go/_std_1.18/src/crypto/crypto.go b/contrib/go/_std_1.18/src/crypto/crypto.go
deleted file mode 100644
index fe1c0690bc..0000000000
--- a/contrib/go/_std_1.18/src/crypto/crypto.go
+++ /dev/null
@@ -1,223 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package crypto collects common cryptographic constants.
-package crypto
-
-import (
-	"hash"
-	"io"
-	"strconv"
-)
-
-// Hash identifies a cryptographic hash function that is implemented in another
-// package.
-type Hash uint
-
-// HashFunc simply returns the value of h so that Hash implements SignerOpts.
-func (h Hash) HashFunc() Hash {
-	return h
-}
-
-func (h Hash) String() string {
-	switch h {
-	case MD4:
-		return "MD4"
-	case MD5:
-		return "MD5"
-	case SHA1:
-		return "SHA-1"
-	case SHA224:
-		return "SHA-224"
-	case SHA256:
-		return "SHA-256"
-	case SHA384:
-		return "SHA-384"
-	case SHA512:
-		return "SHA-512"
-	case MD5SHA1:
-		return "MD5+SHA1"
-	case RIPEMD160:
-		return "RIPEMD-160"
-	case SHA3_224:
-		return "SHA3-224"
-	case SHA3_256:
-		return "SHA3-256"
-	case SHA3_384:
-		return "SHA3-384"
-	case SHA3_512:
-		return "SHA3-512"
-	case SHA512_224:
-		return "SHA-512/224"
-	case SHA512_256:
-		return "SHA-512/256"
-	case BLAKE2s_256:
-		return "BLAKE2s-256"
-	case BLAKE2b_256:
-		return "BLAKE2b-256"
-	case BLAKE2b_384:
-		return "BLAKE2b-384"
-	case BLAKE2b_512:
-		return "BLAKE2b-512"
-	default:
-		return "unknown hash value " + strconv.Itoa(int(h))
-	}
-}
-
-const (
-	MD4         Hash = 1 + iota // import golang.org/x/crypto/md4
-	MD5                         // import crypto/md5
-	SHA1                        // import crypto/sha1
-	SHA224                      // import crypto/sha256
-	SHA256                      // import crypto/sha256
-	SHA384                      // import crypto/sha512
-	SHA512                      // import crypto/sha512
-	MD5SHA1                     // no implementation; MD5+SHA1 used for TLS RSA
-	RIPEMD160                   // import golang.org/x/crypto/ripemd160
-	SHA3_224                    // import golang.org/x/crypto/sha3
-	SHA3_256                    // import golang.org/x/crypto/sha3
-	SHA3_384                    // import golang.org/x/crypto/sha3
-	SHA3_512                    // import golang.org/x/crypto/sha3
-	SHA512_224                  // import crypto/sha512
-	SHA512_256                  // import crypto/sha512
-	BLAKE2s_256                 // import golang.org/x/crypto/blake2s
-	BLAKE2b_256                 // import golang.org/x/crypto/blake2b
-	BLAKE2b_384                 // import golang.org/x/crypto/blake2b
-	BLAKE2b_512                 // import golang.org/x/crypto/blake2b
-	maxHash
-)
-
-var digestSizes = []uint8{
-	MD4:         16,
-	MD5:         16,
-	SHA1:        20,
-	SHA224:      28,
-	SHA256:      32,
-	SHA384:      48,
-	SHA512:      64,
-	SHA512_224:  28,
-	SHA512_256:  32,
-	SHA3_224:    28,
-	SHA3_256:    32,
-	SHA3_384:    48,
-	SHA3_512:    64,
-	MD5SHA1:     36,
-	RIPEMD160:   20,
-	BLAKE2s_256: 32,
-	BLAKE2b_256: 32,
-	BLAKE2b_384: 48,
-	BLAKE2b_512: 64,
-}
-
-// Size returns the length, in bytes, of a digest resulting from the given hash
-// function. It doesn't require that the hash function in question be linked
-// into the program.
-func (h Hash) Size() int {
-	if h > 0 && h < maxHash {
-		return int(digestSizes[h])
-	}
-	panic("crypto: Size of unknown hash function")
-}
-
-var hashes = make([]func() hash.Hash, maxHash)
-
-// New returns a new hash.Hash calculating the given hash function. New panics
-// if the hash function is not linked into the binary.
-func (h Hash) New() hash.Hash {
-	if h > 0 && h < maxHash {
-		f := hashes[h]
-		if f != nil {
-			return f()
-		}
-	}
-	panic("crypto: requested hash function #" + strconv.Itoa(int(h)) + " is unavailable")
-}
-
-// Available reports whether the given hash function is linked into the binary.
-func (h Hash) Available() bool {
-	return h < maxHash && hashes[h] != nil
-}
-
-// RegisterHash registers a function that returns a new instance of the given
-// hash function. This is intended to be called from the init function in
-// packages that implement hash functions.
-func RegisterHash(h Hash, f func() hash.Hash) {
-	if h >= maxHash {
-		panic("crypto: RegisterHash of unknown hash function")
-	}
-	hashes[h] = f
-}
-
-// PublicKey represents a public key using an unspecified algorithm.
-//
-// Although this type is an empty interface for backwards compatibility reasons,
-// all public key types in the standard library implement the following interface
-//
-//     interface{
-//         Equal(x crypto.PublicKey) bool
-//     }
-//
-// which can be used for increased type safety within applications.
-type PublicKey any
-
-// PrivateKey represents a private key using an unspecified algorithm.
-//
-// Although this type is an empty interface for backwards compatibility reasons,
-// all private key types in the standard library implement the following interface
-//
-//     interface{
-//         Public() crypto.PublicKey
-//         Equal(x crypto.PrivateKey) bool
-//     }
-//
-// as well as purpose-specific interfaces such as Signer and Decrypter, which
-// can be used for increased type safety within applications.
-type PrivateKey any
-
-// Signer is an interface for an opaque private key that can be used for
-// signing operations. For example, an RSA key kept in a hardware module.
-type Signer interface {
-	// Public returns the public key corresponding to the opaque,
-	// private key.
-	Public() PublicKey
-
-	// Sign signs digest with the private key, possibly using entropy from
-	// rand. For an RSA key, the resulting signature should be either a
-	// PKCS #1 v1.5 or PSS signature (as indicated by opts). For an (EC)DSA
-	// key, it should be a DER-serialised, ASN.1 signature structure.
-	//
-	// Hash implements the SignerOpts interface and, in most cases, one can
-	// simply pass in the hash function used as opts. Sign may also attempt
-	// to type assert opts to other types in order to obtain algorithm
-	// specific values. See the documentation in each package for details.
-	//
-	// Note that when a signature of a hash of a larger message is needed,
-	// the caller is responsible for hashing the larger message and passing
-	// the hash (as digest) and the hash function (as opts) to Sign.
-	Sign(rand io.Reader, digest []byte, opts SignerOpts) (signature []byte, err error)
-}
-
-// SignerOpts contains options for signing with a Signer.
-type SignerOpts interface {
-	// HashFunc returns an identifier for the hash function used to produce
-	// the message passed to Signer.Sign, or else zero to indicate that no
-	// hashing was done.
-	HashFunc() Hash
-}
-
-// Decrypter is an interface for an opaque private key that can be used for
-// asymmetric decryption operations. An example would be an RSA key
-// kept in a hardware module.
-type Decrypter interface {
-	// Public returns the public key corresponding to the opaque,
-	// private key.
-	Public() PublicKey
-
-	// Decrypt decrypts msg. The opts argument should be appropriate for
-	// the primitive used. See the documentation in each implementation for
-	// details.
-	Decrypt(rand io.Reader, msg []byte, opts DecrypterOpts) (plaintext []byte, err error)
-}
-
-type DecrypterOpts any
diff --git a/contrib/go/_std_1.18/src/crypto/des/block.go b/contrib/go/_std_1.18/src/crypto/des/block.go
deleted file mode 100644
index cc2888e2c7..0000000000
--- a/contrib/go/_std_1.18/src/crypto/des/block.go
+++ /dev/null
@@ -1,263 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package des
-
-import (
-	"encoding/binary"
-	"sync"
-)
-
-func cryptBlock(subkeys []uint64, dst, src []byte, decrypt bool) {
-	b := binary.BigEndian.Uint64(src)
-	b = permuteInitialBlock(b)
-	left, right := uint32(b>>32), uint32(b)
-
-	left = (left << 1) | (left >> 31)
-	right = (right << 1) | (right >> 31)
-
-	if decrypt {
-		for i := 0; i < 8; i++ {
-			left, right = feistel(left, right, subkeys[15-2*i], subkeys[15-(2*i+1)])
-		}
-	} else {
-		for i := 0; i < 8; i++ {
-			left, right = feistel(left, right, subkeys[2*i], subkeys[2*i+1])
-		}
-	}
-
-	left = (left << 31) | (left >> 1)
-	right = (right << 31) | (right >> 1)
-
-	// switch left & right and perform final permutation
-	preOutput := (uint64(right) << 32) | uint64(left)
-	binary.BigEndian.PutUint64(dst, permuteFinalBlock(preOutput))
-}
-
-// Encrypt one block from src into dst, using the subkeys.
-func encryptBlock(subkeys []uint64, dst, src []byte) {
-	cryptBlock(subkeys, dst, src, false)
-}
-
-// Decrypt one block from src into dst, using the subkeys.
-func decryptBlock(subkeys []uint64, dst, src []byte) {
-	cryptBlock(subkeys, dst, src, true)
-}
-
-// DES Feistel function. feistelBox must be initialized via
-// feistelBoxOnce.Do(initFeistelBox) first.
-func feistel(l, r uint32, k0, k1 uint64) (lout, rout uint32) {
-	var t uint32
-
-	t = r ^ uint32(k0>>32)
-	l ^= feistelBox[7][t&0x3f] ^
-		feistelBox[5][(t>>8)&0x3f] ^
-		feistelBox[3][(t>>16)&0x3f] ^
-		feistelBox[1][(t>>24)&0x3f]
-
-	t = ((r << 28) | (r >> 4)) ^ uint32(k0)
-	l ^= feistelBox[6][(t)&0x3f] ^
-		feistelBox[4][(t>>8)&0x3f] ^
-		feistelBox[2][(t>>16)&0x3f] ^
-		feistelBox[0][(t>>24)&0x3f]
-
-	t = l ^ uint32(k1>>32)
-	r ^= feistelBox[7][t&0x3f] ^
-		feistelBox[5][(t>>8)&0x3f] ^
-		feistelBox[3][(t>>16)&0x3f] ^
-		feistelBox[1][(t>>24)&0x3f]
-
-	t = ((l << 28) | (l >> 4)) ^ uint32(k1)
-	r ^= feistelBox[6][(t)&0x3f] ^
-		feistelBox[4][(t>>8)&0x3f] ^
-		feistelBox[2][(t>>16)&0x3f] ^
-		feistelBox[0][(t>>24)&0x3f]
-
-	return l, r
-}
-
-// feistelBox[s][16*i+j] contains the output of permutationFunction
-// for sBoxes[s][i][j] << 4*(7-s)
-var feistelBox [8][64]uint32
-
-var feistelBoxOnce sync.Once
-
-// general purpose function to perform DES block permutations
-func permuteBlock(src uint64, permutation []uint8) (block uint64) {
-	for position, n := range permutation {
-		bit := (src >> n) & 1
-		block |= bit << uint((len(permutation)-1)-position)
-	}
-	return
-}
-
-func initFeistelBox() {
-	for s := range sBoxes {
-		for i := 0; i < 4; i++ {
-			for j := 0; j < 16; j++ {
-				f := uint64(sBoxes[s][i][j]) << (4 * (7 - uint(s)))
-				f = permuteBlock(f, permutationFunction[:])
-
-				// Row is determined by the 1st and 6th bit.
-				// Column is the middle four bits.
-				row := uint8(((i & 2) << 4) | i&1)
-				col := uint8(j << 1)
-				t := row | col
-
-				// The rotation was performed in the feistel rounds, being factored out and now mixed into the feistelBox.
-				f = (f << 1) | (f >> 31)
-
-				feistelBox[s][t] = uint32(f)
-			}
-		}
-	}
-}
-
-// permuteInitialBlock is equivalent to the permutation defined
-// by initialPermutation.
-func permuteInitialBlock(block uint64) uint64 {
-	// block = b7 b6 b5 b4 b3 b2 b1 b0 (8 bytes)
-	b1 := block >> 48
-	b2 := block << 48
-	block ^= b1 ^ b2 ^ b1<<48 ^ b2>>48
-
-	// block = b1 b0 b5 b4 b3 b2 b7 b6
-	b1 = block >> 32 & 0xff00ff
-	b2 = (block & 0xff00ff00)
-	block ^= b1<<32 ^ b2 ^ b1<<8 ^ b2<<24 // exchange b0 b4 with b3 b7
-
-	// block is now b1 b3 b5 b7 b0 b2 b4 b6, the permutation:
-	//                  ...  8
-	//                  ... 24
-	//                  ... 40
-	//                  ... 56
-	//  7  6  5  4  3  2  1  0
-	// 23 22 21 20 19 18 17 16
-	//                  ... 32
-	//                  ... 48
-
-	// exchange 4,5,6,7 with 32,33,34,35 etc.
-	b1 = block & 0x0f0f00000f0f0000
-	b2 = block & 0x0000f0f00000f0f0
-	block ^= b1 ^ b2 ^ b1>>12 ^ b2<<12
-
-	// block is the permutation:
-	//
-	//   [+8]         [+40]
-	//
-	//  7  6  5  4
-	// 23 22 21 20
-	//  3  2  1  0
-	// 19 18 17 16    [+32]
-
-	// exchange 0,1,4,5 with 18,19,22,23
-	b1 = block & 0x3300330033003300
-	b2 = block & 0x00cc00cc00cc00cc
-	block ^= b1 ^ b2 ^ b1>>6 ^ b2<<6
-
-	// block is the permutation:
-	// 15 14
-	// 13 12
-	// 11 10
-	//  9  8
-	//  7  6
-	//  5  4
-	//  3  2
-	//  1  0 [+16] [+32] [+64]
-
-	// exchange 0,2,4,6 with 9,11,13,15:
-	b1 = block & 0xaaaaaaaa55555555
-	block ^= b1 ^ b1>>33 ^ b1<<33
-
-	// block is the permutation:
-	// 6 14 22 30 38 46 54 62
-	// 4 12 20 28 36 44 52 60
-	// 2 10 18 26 34 42 50 58
-	// 0  8 16 24 32 40 48 56
-	// 7 15 23 31 39 47 55 63
-	// 5 13 21 29 37 45 53 61
-	// 3 11 19 27 35 43 51 59
-	// 1  9 17 25 33 41 49 57
-	return block
-}
-
-// permuteInitialBlock is equivalent to the permutation defined
-// by finalPermutation.
-func permuteFinalBlock(block uint64) uint64 {
-	// Perform the same bit exchanges as permuteInitialBlock
-	// but in reverse order.
-	b1 := block & 0xaaaaaaaa55555555
-	block ^= b1 ^ b1>>33 ^ b1<<33
-
-	b1 = block & 0x3300330033003300
-	b2 := block & 0x00cc00cc00cc00cc
-	block ^= b1 ^ b2 ^ b1>>6 ^ b2<<6
-
-	b1 = block & 0x0f0f00000f0f0000
-	b2 = block & 0x0000f0f00000f0f0
-	block ^= b1 ^ b2 ^ b1>>12 ^ b2<<12
-
-	b1 = block >> 32 & 0xff00ff
-	b2 = (block & 0xff00ff00)
-	block ^= b1<<32 ^ b2 ^ b1<<8 ^ b2<<24
-
-	b1 = block >> 48
-	b2 = block << 48
-	block ^= b1 ^ b2 ^ b1<<48 ^ b2>>48
-	return block
-}
-
-// creates 16 28-bit blocks rotated according
-// to the rotation schedule
-func ksRotate(in uint32) (out []uint32) {
-	out = make([]uint32, 16)
-	last := in
-	for i := 0; i < 16; i++ {
-		// 28-bit circular left shift
-		left := (last << (4 + ksRotations[i])) >> 4
-		right := (last << 4) >> (32 - ksRotations[i])
-		out[i] = left | right
-		last = out[i]
-	}
-	return
-}
-
-// creates 16 56-bit subkeys from the original key
-func (c *desCipher) generateSubkeys(keyBytes []byte) {
-	feistelBoxOnce.Do(initFeistelBox)
-
-	// apply PC1 permutation to key
-	key := binary.BigEndian.Uint64(keyBytes)
-	permutedKey := permuteBlock(key, permutedChoice1[:])
-
-	// rotate halves of permuted key according to the rotation schedule
-	leftRotations := ksRotate(uint32(permutedKey >> 28))
-	rightRotations := ksRotate(uint32(permutedKey<<4) >> 4)
-
-	// generate subkeys
-	for i := 0; i < 16; i++ {
-		// combine halves to form 56-bit input to PC2
-		pc2Input := uint64(leftRotations[i])<<28 | uint64(rightRotations[i])
-		// apply PC2 permutation to 7 byte input
-		c.subkeys[i] = unpack(permuteBlock(pc2Input, permutedChoice2[:]))
-	}
-}
-
-// Expand 48-bit input to 64-bit, with each 6-bit block padded by extra two bits at the top.
-// By doing so, we can have the input blocks (four bits each), and the key blocks (six bits each) well-aligned without
-// extra shifts/rotations for alignments.
-func unpack(x uint64) uint64 {
-	var result uint64
-
-	result = ((x>>(6*1))&0xff)<<(8*0) |
-		((x>>(6*3))&0xff)<<(8*1) |
-		((x>>(6*5))&0xff)<<(8*2) |
-		((x>>(6*7))&0xff)<<(8*3) |
-		((x>>(6*0))&0xff)<<(8*4) |
-		((x>>(6*2))&0xff)<<(8*5) |
-		((x>>(6*4))&0xff)<<(8*6) |
-		((x>>(6*6))&0xff)<<(8*7)
-
-	return result
-}
diff --git a/contrib/go/_std_1.18/src/crypto/ecdsa/ecdsa.go b/contrib/go/_std_1.18/src/crypto/ecdsa/ecdsa.go
deleted file mode 100644
index 9f9a09a884..0000000000
--- a/contrib/go/_std_1.18/src/crypto/ecdsa/ecdsa.go
+++ /dev/null
@@ -1,368 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package ecdsa implements the Elliptic Curve Digital Signature Algorithm, as
-// defined in FIPS 186-4 and SEC 1, Version 2.0.
-//
-// Signatures generated by this package are not deterministic, but entropy is
-// mixed with the private key and the message, achieving the same level of
-// security in case of randomness source failure.
-package ecdsa
-
-// [FIPS 186-4] references ANSI X9.62-2005 for the bulk of the ECDSA algorithm.
-// That standard is not freely available, which is a problem in an open source
-// implementation, because not only the implementer, but also any maintainer,
-// contributor, reviewer, auditor, and learner needs access to it. Instead, this
-// package references and follows the equivalent [SEC 1, Version 2.0].
-//
-// [FIPS 186-4]: https://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.186-4.pdf
-// [SEC 1, Version 2.0]: https://www.secg.org/sec1-v2.pdf
-
-import (
-	"crypto"
-	"crypto/aes"
-	"crypto/cipher"
-	"crypto/elliptic"
-	"crypto/internal/randutil"
-	"crypto/sha512"
-	"errors"
-	"io"
-	"math/big"
-
-	"golang.org/x/crypto/cryptobyte"
-	"golang.org/x/crypto/cryptobyte/asn1"
-)
-
-// A invertible implements fast inverse in GF(N).
-type invertible interface {
-	// Inverse returns the inverse of k mod Params().N.
-	Inverse(k *big.Int) *big.Int
-}
-
-// A combinedMult implements fast combined multiplication for verification.
-type combinedMult interface {
-	// CombinedMult returns [s1]G + [s2]P where G is the generator.
-	CombinedMult(Px, Py *big.Int, s1, s2 []byte) (x, y *big.Int)
-}
-
-const (
-	aesIV = "IV for ECDSA CTR"
-)
-
-// PublicKey represents an ECDSA public key.
-type PublicKey struct {
-	elliptic.Curve
-	X, Y *big.Int
-}
-
-// Any methods implemented on PublicKey might need to also be implemented on
-// PrivateKey, as the latter embeds the former and will expose its methods.
-
-// Equal reports whether pub and x have the same value.
-//
-// Two keys are only considered to have the same value if they have the same Curve value.
-// Note that for example elliptic.P256() and elliptic.P256().Params() are different
-// values, as the latter is a generic not constant time implementation.
-func (pub *PublicKey) Equal(x crypto.PublicKey) bool {
-	xx, ok := x.(*PublicKey)
-	if !ok {
-		return false
-	}
-	return pub.X.Cmp(xx.X) == 0 && pub.Y.Cmp(xx.Y) == 0 &&
-		// Standard library Curve implementations are singletons, so this check
-		// will work for those. Other Curves might be equivalent even if not
-		// singletons, but there is no definitive way to check for that, and
-		// better to err on the side of safety.
-		pub.Curve == xx.Curve
-}
-
-// PrivateKey represents an ECDSA private key.
-type PrivateKey struct {
-	PublicKey
-	D *big.Int
-}
-
-// Public returns the public key corresponding to priv.
-func (priv *PrivateKey) Public() crypto.PublicKey {
-	return &priv.PublicKey
-}
-
-// Equal reports whether priv and x have the same value.
-//
-// See PublicKey.Equal for details on how Curve is compared.
-func (priv *PrivateKey) Equal(x crypto.PrivateKey) bool {
-	xx, ok := x.(*PrivateKey)
-	if !ok {
-		return false
-	}
-	return priv.PublicKey.Equal(&xx.PublicKey) && priv.D.Cmp(xx.D) == 0
-}
-
-// Sign signs digest with priv, reading randomness from rand. The opts argument
-// is not currently used but, in keeping with the crypto.Signer interface,
-// should be the hash function used to digest the message.
-//
-// This method implements crypto.Signer, which is an interface to support keys
-// where the private part is kept in, for example, a hardware module. Common
-// uses can use the SignASN1 function in this package directly.
-func (priv *PrivateKey) Sign(rand io.Reader, digest []byte, opts crypto.SignerOpts) ([]byte, error) {
-	r, s, err := Sign(rand, priv, digest)
-	if err != nil {
-		return nil, err
-	}
-
-	var b cryptobyte.Builder
-	b.AddASN1(asn1.SEQUENCE, func(b *cryptobyte.Builder) {
-		b.AddASN1BigInt(r)
-		b.AddASN1BigInt(s)
-	})
-	return b.Bytes()
-}
-
-var one = new(big.Int).SetInt64(1)
-
-// randFieldElement returns a random element of the order of the given
-// curve using the procedure given in FIPS 186-4, Appendix B.5.1.
-func randFieldElement(c elliptic.Curve, rand io.Reader) (k *big.Int, err error) {
-	params := c.Params()
-	// Note that for P-521 this will actually be 63 bits more than the order, as
-	// division rounds down, but the extra bit is inconsequential.
-	b := make([]byte, params.BitSize/8+8) // TODO: use params.N.BitLen()
-	_, err = io.ReadFull(rand, b)
-	if err != nil {
-		return
-	}
-
-	k = new(big.Int).SetBytes(b)
-	n := new(big.Int).Sub(params.N, one)
-	k.Mod(k, n)
-	k.Add(k, one)
-	return
-}
-
-// GenerateKey generates a public and private key pair.
-func GenerateKey(c elliptic.Curve, rand io.Reader) (*PrivateKey, error) {
-	k, err := randFieldElement(c, rand)
-	if err != nil {
-		return nil, err
-	}
-
-	priv := new(PrivateKey)
-	priv.PublicKey.Curve = c
-	priv.D = k
-	priv.PublicKey.X, priv.PublicKey.Y = c.ScalarBaseMult(k.Bytes())
-	return priv, nil
-}
-
-// hashToInt converts a hash value to an integer. Per FIPS 186-4, Section 6.4,
-// we use the left-most bits of the hash to match the bit-length of the order of
-// the curve. This also performs Step 5 of SEC 1, Version 2.0, Section 4.1.3.
-func hashToInt(hash []byte, c elliptic.Curve) *big.Int {
-	orderBits := c.Params().N.BitLen()
-	orderBytes := (orderBits + 7) / 8
-	if len(hash) > orderBytes {
-		hash = hash[:orderBytes]
-	}
-
-	ret := new(big.Int).SetBytes(hash)
-	excess := len(hash)*8 - orderBits
-	if excess > 0 {
-		ret.Rsh(ret, uint(excess))
-	}
-	return ret
-}
-
-// fermatInverse calculates the inverse of k in GF(P) using Fermat's method
-// (exponentiation modulo P - 2, per Euler's theorem). This has better
-// constant-time properties than Euclid's method (implemented in
-// math/big.Int.ModInverse and FIPS 186-4, Appendix C.1) although math/big
-// itself isn't strictly constant-time so it's not perfect.
-func fermatInverse(k, N *big.Int) *big.Int {
-	two := big.NewInt(2)
-	nMinus2 := new(big.Int).Sub(N, two)
-	return new(big.Int).Exp(k, nMinus2, N)
-}
-
-var errZeroParam = errors.New("zero parameter")
-
-// Sign signs a hash (which should be the result of hashing a larger message)
-// using the private key, priv. If the hash is longer than the bit-length of the
-// private key's curve order, the hash will be truncated to that length. It
-// returns the signature as a pair of integers. Most applications should use
-// SignASN1 instead of dealing directly with r, s.
-func Sign(rand io.Reader, priv *PrivateKey, hash []byte) (r, s *big.Int, err error) {
-	randutil.MaybeReadByte(rand)
-
-	// This implementation derives the nonce from an AES-CTR CSPRNG keyed by:
-	//
-	//    SHA2-512(priv.D || entropy || hash)[:32]
-	//
-	// The CSPRNG key is indifferentiable from a random oracle as shown in
-	// [Coron], the AES-CTR stream is indifferentiable from a random oracle
-	// under standard cryptographic assumptions (see [Larsson] for examples).
-	//
-	// [Coron]: https://cs.nyu.edu/~dodis/ps/merkle.pdf
-	// [Larsson]: https://web.archive.org/web/20040719170906/https://www.nada.kth.se/kurser/kth/2D1441/semteo03/lecturenotes/assump.pdf
-
-	// Get 256 bits of entropy from rand.
-	entropy := make([]byte, 32)
-	_, err = io.ReadFull(rand, entropy)
-	if err != nil {
-		return
-	}
-
-	// Initialize an SHA-512 hash context; digest...
-	md := sha512.New()
-	md.Write(priv.D.Bytes()) // the private key,
-	md.Write(entropy)        // the entropy,
-	md.Write(hash)           // and the input hash;
-	key := md.Sum(nil)[:32]  // and compute ChopMD-256(SHA-512),
-	// which is an indifferentiable MAC.
-
-	// Create an AES-CTR instance to use as a CSPRNG.
-	block, err := aes.NewCipher(key)
-	if err != nil {
-		return nil, nil, err
-	}
-
-	// Create a CSPRNG that xors a stream of zeros with
-	// the output of the AES-CTR instance.
-	csprng := cipher.StreamReader{
-		R: zeroReader,
-		S: cipher.NewCTR(block, []byte(aesIV)),
-	}
-
-	c := priv.PublicKey.Curve
-	return sign(priv, &csprng, c, hash)
-}
-
-func signGeneric(priv *PrivateKey, csprng *cipher.StreamReader, c elliptic.Curve, hash []byte) (r, s *big.Int, err error) {
-	// SEC 1, Version 2.0, Section 4.1.3
-	N := c.Params().N
-	if N.Sign() == 0 {
-		return nil, nil, errZeroParam
-	}
-	var k, kInv *big.Int
-	for {
-		for {
-			k, err = randFieldElement(c, *csprng)
-			if err != nil {
-				r = nil
-				return
-			}
-
-			if in, ok := priv.Curve.(invertible); ok {
-				kInv = in.Inverse(k)
-			} else {
-				kInv = fermatInverse(k, N) // N != 0
-			}
-
-			r, _ = priv.Curve.ScalarBaseMult(k.Bytes())
-			r.Mod(r, N)
-			if r.Sign() != 0 {
-				break
-			}
-		}
-
-		e := hashToInt(hash, c)
-		s = new(big.Int).Mul(priv.D, r)
-		s.Add(s, e)
-		s.Mul(s, kInv)
-		s.Mod(s, N) // N != 0
-		if s.Sign() != 0 {
-			break
-		}
-	}
-
-	return
-}
-
-// SignASN1 signs a hash (which should be the result of hashing a larger message)
-// using the private key, priv. If the hash is longer than the bit-length of the
-// private key's curve order, the hash will be truncated to that length. It
-// returns the ASN.1 encoded signature.
-func SignASN1(rand io.Reader, priv *PrivateKey, hash []byte) ([]byte, error) {
-	return priv.Sign(rand, hash, nil)
-}
-
-// Verify verifies the signature in r, s of hash using the public key, pub. Its
-// return value records whether the signature is valid. Most applications should
-// use VerifyASN1 instead of dealing directly with r, s.
-func Verify(pub *PublicKey, hash []byte, r, s *big.Int) bool {
-	c := pub.Curve
-	N := c.Params().N
-
-	if r.Sign() <= 0 || s.Sign() <= 0 {
-		return false
-	}
-	if r.Cmp(N) >= 0 || s.Cmp(N) >= 0 {
-		return false
-	}
-	return verify(pub, c, hash, r, s)
-}
-
-func verifyGeneric(pub *PublicKey, c elliptic.Curve, hash []byte, r, s *big.Int) bool {
-	// SEC 1, Version 2.0, Section 4.1.4
-	e := hashToInt(hash, c)
-	var w *big.Int
-	N := c.Params().N
-	if in, ok := c.(invertible); ok {
-		w = in.Inverse(s)
-	} else {
-		w = new(big.Int).ModInverse(s, N)
-	}
-
-	u1 := e.Mul(e, w)
-	u1.Mod(u1, N)
-	u2 := w.Mul(r, w)
-	u2.Mod(u2, N)
-
-	// Check if implements S1*g + S2*p
-	var x, y *big.Int
-	if opt, ok := c.(combinedMult); ok {
-		x, y = opt.CombinedMult(pub.X, pub.Y, u1.Bytes(), u2.Bytes())
-	} else {
-		x1, y1 := c.ScalarBaseMult(u1.Bytes())
-		x2, y2 := c.ScalarMult(pub.X, pub.Y, u2.Bytes())
-		x, y = c.Add(x1, y1, x2, y2)
-	}
-
-	if x.Sign() == 0 && y.Sign() == 0 {
-		return false
-	}
-	x.Mod(x, N)
-	return x.Cmp(r) == 0
-}
-
-// VerifyASN1 verifies the ASN.1 encoded signature, sig, of hash using the
-// public key, pub. Its return value records whether the signature is valid.
-func VerifyASN1(pub *PublicKey, hash, sig []byte) bool {
-	var (
-		r, s  = &big.Int{}, &big.Int{}
-		inner cryptobyte.String
-	)
-	input := cryptobyte.String(sig)
-	if !input.ReadASN1(&inner, asn1.SEQUENCE) ||
-		!input.Empty() ||
-		!inner.ReadASN1Integer(r) ||
-		!inner.ReadASN1Integer(s) ||
-		!inner.Empty() {
-		return false
-	}
-	return Verify(pub, hash, r, s)
-}
-
-type zr struct {
-	io.Reader
-}
-
-// Read replaces the contents of dst with zeros.
-func (z *zr) Read(dst []byte) (n int, err error) {
-	for i := range dst {
-		dst[i] = 0
-	}
-	return len(dst), nil
-}
-
-var zeroReader = &zr{}
diff --git a/contrib/go/_std_1.18/src/crypto/ed25519/ed25519.go b/contrib/go/_std_1.18/src/crypto/ed25519/ed25519.go
deleted file mode 100644
index 09c5269d0c..0000000000
--- a/contrib/go/_std_1.18/src/crypto/ed25519/ed25519.go
+++ /dev/null
@@ -1,215 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package ed25519 implements the Ed25519 signature algorithm. See
-// https://ed25519.cr.yp.to/.
-//
-// These functions are also compatible with the “Ed25519” function defined in
-// RFC 8032. However, unlike RFC 8032's formulation, this package's private key
-// representation includes a public key suffix to make multiple signing
-// operations with the same key more efficient. This package refers to the RFC
-// 8032 private key as the “seed”.
-package ed25519
-
-import (
-	"bytes"
-	"crypto"
-	"crypto/ed25519/internal/edwards25519"
-	cryptorand "crypto/rand"
-	"crypto/sha512"
-	"errors"
-	"io"
-	"strconv"
-)
-
-const (
-	// PublicKeySize is the size, in bytes, of public keys as used in this package.
-	PublicKeySize = 32
-	// PrivateKeySize is the size, in bytes, of private keys as used in this package.
-	PrivateKeySize = 64
-	// SignatureSize is the size, in bytes, of signatures generated and verified by this package.
-	SignatureSize = 64
-	// SeedSize is the size, in bytes, of private key seeds. These are the private key representations used by RFC 8032.
-	SeedSize = 32
-)
-
-// PublicKey is the type of Ed25519 public keys.
-type PublicKey []byte
-
-// Any methods implemented on PublicKey might need to also be implemented on
-// PrivateKey, as the latter embeds the former and will expose its methods.
-
-// Equal reports whether pub and x have the same value.
-func (pub PublicKey) Equal(x crypto.PublicKey) bool {
-	xx, ok := x.(PublicKey)
-	if !ok {
-		return false
-	}
-	return bytes.Equal(pub, xx)
-}
-
-// PrivateKey is the type of Ed25519 private keys. It implements crypto.Signer.
-type PrivateKey []byte
-
-// Public returns the PublicKey corresponding to priv.
-func (priv PrivateKey) Public() crypto.PublicKey {
-	publicKey := make([]byte, PublicKeySize)
-	copy(publicKey, priv[32:])
-	return PublicKey(publicKey)
-}
-
-// Equal reports whether priv and x have the same value.
-func (priv PrivateKey) Equal(x crypto.PrivateKey) bool {
-	xx, ok := x.(PrivateKey)
-	if !ok {
-		return false
-	}
-	return bytes.Equal(priv, xx)
-}
-
-// Seed returns the private key seed corresponding to priv. It is provided for
-// interoperability with RFC 8032. RFC 8032's private keys correspond to seeds
-// in this package.
-func (priv PrivateKey) Seed() []byte {
-	seed := make([]byte, SeedSize)
-	copy(seed, priv[:32])
-	return seed
-}
-
-// Sign signs the given message with priv.
-// Ed25519 performs two passes over messages to be signed and therefore cannot
-// handle pre-hashed messages. Thus opts.HashFunc() must return zero to
-// indicate the message hasn't been hashed. This can be achieved by passing
-// crypto.Hash(0) as the value for opts.
-func (priv PrivateKey) Sign(rand io.Reader, message []byte, opts crypto.SignerOpts) (signature []byte, err error) {
-	if opts.HashFunc() != crypto.Hash(0) {
-		return nil, errors.New("ed25519: cannot sign hashed message")
-	}
-
-	return Sign(priv, message), nil
-}
-
-// GenerateKey generates a public/private key pair using entropy from rand.
-// If rand is nil, crypto/rand.Reader will be used.
-func GenerateKey(rand io.Reader) (PublicKey, PrivateKey, error) {
-	if rand == nil {
-		rand = cryptorand.Reader
-	}
-
-	seed := make([]byte, SeedSize)
-	if _, err := io.ReadFull(rand, seed); err != nil {
-		return nil, nil, err
-	}
-
-	privateKey := NewKeyFromSeed(seed)
-	publicKey := make([]byte, PublicKeySize)
-	copy(publicKey, privateKey[32:])
-
-	return publicKey, privateKey, nil
-}
-
-// NewKeyFromSeed calculates a private key from a seed. It will panic if
-// len(seed) is not SeedSize. This function is provided for interoperability
-// with RFC 8032. RFC 8032's private keys correspond to seeds in this
-// package.
-func NewKeyFromSeed(seed []byte) PrivateKey {
-	// Outline the function body so that the returned key can be stack-allocated.
-	privateKey := make([]byte, PrivateKeySize)
-	newKeyFromSeed(privateKey, seed)
-	return privateKey
-}
-
-func newKeyFromSeed(privateKey, seed []byte) {
-	if l := len(seed); l != SeedSize {
-		panic("ed25519: bad seed length: " + strconv.Itoa(l))
-	}
-
-	h := sha512.Sum512(seed)
-	s := edwards25519.NewScalar().SetBytesWithClamping(h[:32])
-	A := (&edwards25519.Point{}).ScalarBaseMult(s)
-
-	publicKey := A.Bytes()
-
-	copy(privateKey, seed)
-	copy(privateKey[32:], publicKey)
-}
-
-// Sign signs the message with privateKey and returns a signature. It will
-// panic if len(privateKey) is not PrivateKeySize.
-func Sign(privateKey PrivateKey, message []byte) []byte {
-	// Outline the function body so that the returned signature can be
-	// stack-allocated.
-	signature := make([]byte, SignatureSize)
-	sign(signature, privateKey, message)
-	return signature
-}
-
-func sign(signature, privateKey, message []byte) {
-	if l := len(privateKey); l != PrivateKeySize {
-		panic("ed25519: bad private key length: " + strconv.Itoa(l))
-	}
-	seed, publicKey := privateKey[:SeedSize], privateKey[SeedSize:]
-
-	h := sha512.Sum512(seed)
-	s := edwards25519.NewScalar().SetBytesWithClamping(h[:32])
-	prefix := h[32:]
-
-	mh := sha512.New()
-	mh.Write(prefix)
-	mh.Write(message)
-	messageDigest := make([]byte, 0, sha512.Size)
-	messageDigest = mh.Sum(messageDigest)
-	r := edwards25519.NewScalar().SetUniformBytes(messageDigest)
-
-	R := (&edwards25519.Point{}).ScalarBaseMult(r)
-
-	kh := sha512.New()
-	kh.Write(R.Bytes())
-	kh.Write(publicKey)
-	kh.Write(message)
-	hramDigest := make([]byte, 0, sha512.Size)
-	hramDigest = kh.Sum(hramDigest)
-	k := edwards25519.NewScalar().SetUniformBytes(hramDigest)
-
-	S := edwards25519.NewScalar().MultiplyAdd(k, s, r)
-
-	copy(signature[:32], R.Bytes())
-	copy(signature[32:], S.Bytes())
-}
-
-// Verify reports whether sig is a valid signature of message by publicKey. It
-// will panic if len(publicKey) is not PublicKeySize.
-func Verify(publicKey PublicKey, message, sig []byte) bool {
-	if l := len(publicKey); l != PublicKeySize {
-		panic("ed25519: bad public key length: " + strconv.Itoa(l))
-	}
-
-	if len(sig) != SignatureSize || sig[63]&224 != 0 {
-		return false
-	}
-
-	A, err := (&edwards25519.Point{}).SetBytes(publicKey)
-	if err != nil {
-		return false
-	}
-
-	kh := sha512.New()
-	kh.Write(sig[:32])
-	kh.Write(publicKey)
-	kh.Write(message)
-	hramDigest := make([]byte, 0, sha512.Size)
-	hramDigest = kh.Sum(hramDigest)
-	k := edwards25519.NewScalar().SetUniformBytes(hramDigest)
-
-	S, err := edwards25519.NewScalar().SetCanonicalBytes(sig[32:])
-	if err != nil {
-		return false
-	}
-
-	// [S]B = R + [k]A --> [k](-A) + [S]B = R
-	minusA := (&edwards25519.Point{}).Negate(A)
-	R := (&edwards25519.Point{}).VarTimeDoubleScalarBaseMult(k, minusA, S)
-
-	return bytes.Equal(sig[:32], R.Bytes())
-}
diff --git a/contrib/go/_std_1.18/src/crypto/ed25519/internal/edwards25519/doc.go b/contrib/go/_std_1.18/src/crypto/ed25519/internal/edwards25519/doc.go
deleted file mode 100644
index ff31cd23da..0000000000
--- a/contrib/go/_std_1.18/src/crypto/ed25519/internal/edwards25519/doc.go
+++ /dev/null
@@ -1,22 +0,0 @@
-// Copyright (c) 2021 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package edwards25519 implements group logic for the twisted Edwards curve
-//
-//     -x^2 + y^2 = 1 + -(121665/121666)*x^2*y^2
-//
-// This is better known as the Edwards curve equivalent to Curve25519, and is
-// the curve used by the Ed25519 signature scheme.
-//
-// Most users don't need this package, and should instead use crypto/ed25519 for
-// signatures, golang.org/x/crypto/curve25519 for Diffie-Hellman, or
-// github.com/gtank/ristretto255 for prime order group logic.
-//
-// However, developers who do need to interact with low-level edwards25519
-// operations can use filippo.io/edwards25519, an extended version of this
-// package repackaged as an importable module.
-//
-// (Note that filippo.io/edwards25519 and github.com/gtank/ristretto255 are not
-// maintained by the Go team and are not covered by the Go 1 Compatibility Promise.)
-package edwards25519
diff --git a/contrib/go/_std_1.18/src/crypto/ed25519/internal/edwards25519/edwards25519.go b/contrib/go/_std_1.18/src/crypto/ed25519/internal/edwards25519/edwards25519.go
deleted file mode 100644
index 313e6c281c..0000000000
--- a/contrib/go/_std_1.18/src/crypto/ed25519/internal/edwards25519/edwards25519.go
+++ /dev/null
@@ -1,427 +0,0 @@
-// Copyright (c) 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package edwards25519
-
-import (
-	"crypto/ed25519/internal/edwards25519/field"
-	"errors"
-)
-
-// Point types.
-
-type projP1xP1 struct {
-	X, Y, Z, T field.Element
-}
-
-type projP2 struct {
-	X, Y, Z field.Element
-}
-
-// Point represents a point on the edwards25519 curve.
-//
-// This type works similarly to math/big.Int, and all arguments and receivers
-// are allowed to alias.
-//
-// The zero value is NOT valid, and it may be used only as a receiver.
-type Point struct {
-	// The point is internally represented in extended coordinates (X, Y, Z, T)
-	// where x = X/Z, y = Y/Z, and xy = T/Z per https://eprint.iacr.org/2008/522.
-	x, y, z, t field.Element
-
-	// Make the type not comparable (i.e. used with == or as a map key), as
-	// equivalent points can be represented by different Go values.
-	_ incomparable
-}
-
-type incomparable [0]func()
-
-func checkInitialized(points ...*Point) {
-	for _, p := range points {
-		if p.x == (field.Element{}) && p.y == (field.Element{}) {
-			panic("edwards25519: use of uninitialized Point")
-		}
-	}
-}
-
-type projCached struct {
-	YplusX, YminusX, Z, T2d field.Element
-}
-
-type affineCached struct {
-	YplusX, YminusX, T2d field.Element
-}
-
-// Constructors.
-
-func (v *projP2) Zero() *projP2 {
-	v.X.Zero()
-	v.Y.One()
-	v.Z.One()
-	return v
-}
-
-// identity is the point at infinity.
-var identity, _ = new(Point).SetBytes([]byte{
-	1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0})
-
-// NewIdentityPoint returns a new Point set to the identity.
-func NewIdentityPoint() *Point {
-	return new(Point).Set(identity)
-}
-
-// generator is the canonical curve basepoint. See TestGenerator for the
-// correspondence of this encoding with the values in RFC 8032.
-var generator, _ = new(Point).SetBytes([]byte{
-	0x58, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66,
-	0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66,
-	0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66,
-	0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66})
-
-// NewGeneratorPoint returns a new Point set to the canonical generator.
-func NewGeneratorPoint() *Point {
-	return new(Point).Set(generator)
-}
-
-func (v *projCached) Zero() *projCached {
-	v.YplusX.One()
-	v.YminusX.One()
-	v.Z.One()
-	v.T2d.Zero()
-	return v
-}
-
-func (v *affineCached) Zero() *affineCached {
-	v.YplusX.One()
-	v.YminusX.One()
-	v.T2d.Zero()
-	return v
-}
-
-// Assignments.
-
-// Set sets v = u, and returns v.
-func (v *Point) Set(u *Point) *Point {
-	*v = *u
-	return v
-}
-
-// Encoding.
-
-// Bytes returns the canonical 32-byte encoding of v, according to RFC 8032,
-// Section 5.1.2.
-func (v *Point) Bytes() []byte {
-	// This function is outlined to make the allocations inline in the caller
-	// rather than happen on the heap.
-	var buf [32]byte
-	return v.bytes(&buf)
-}
-
-func (v *Point) bytes(buf *[32]byte) []byte {
-	checkInitialized(v)
-
-	var zInv, x, y field.Element
-	zInv.Invert(&v.z)       // zInv = 1 / Z
-	x.Multiply(&v.x, &zInv) // x = X / Z
-	y.Multiply(&v.y, &zInv) // y = Y / Z
-
-	out := copyFieldElement(buf, &y)
-	out[31] |= byte(x.IsNegative() << 7)
-	return out
-}
-
-var feOne = new(field.Element).One()
-
-// SetBytes sets v = x, where x is a 32-byte encoding of v. If x does not
-// represent a valid point on the curve, SetBytes returns nil and an error and
-// the receiver is unchanged. Otherwise, SetBytes returns v.
-//
-// Note that SetBytes accepts all non-canonical encodings of valid points.
-// That is, it follows decoding rules that match most implementations in
-// the ecosystem rather than RFC 8032.
-func (v *Point) SetBytes(x []byte) (*Point, error) {
-	// Specifically, the non-canonical encodings that are accepted are
-	//   1) the ones where the field element is not reduced (see the
-	//      (*field.Element).SetBytes docs) and
-	//   2) the ones where the x-coordinate is zero and the sign bit is set.
-	//
-	// This is consistent with crypto/ed25519/internal/edwards25519. Read more
-	// at https://hdevalence.ca/blog/2020-10-04-its-25519am, specifically the
-	// "Canonical A, R" section.
-
-	if len(x) != 32 {
-		return nil, errors.New("edwards25519: invalid point encoding length")
-	}
-	y := new(field.Element).SetBytes(x)
-
-	// -x² + y² = 1 + dx²y²
-	// x² + dx²y² = x²(dy² + 1) = y² - 1
-	// x² = (y² - 1) / (dy² + 1)
-
-	// u = y² - 1
-	y2 := new(field.Element).Square(y)
-	u := new(field.Element).Subtract(y2, feOne)
-
-	// v = dy² + 1
-	vv := new(field.Element).Multiply(y2, d)
-	vv = vv.Add(vv, feOne)
-
-	// x = +√(u/v)
-	xx, wasSquare := new(field.Element).SqrtRatio(u, vv)
-	if wasSquare == 0 {
-		return nil, errors.New("edwards25519: invalid point encoding")
-	}
-
-	// Select the negative square root if the sign bit is set.
-	xxNeg := new(field.Element).Negate(xx)
-	xx = xx.Select(xxNeg, xx, int(x[31]>>7))
-
-	v.x.Set(xx)
-	v.y.Set(y)
-	v.z.One()
-	v.t.Multiply(xx, y) // xy = T / Z
-
-	return v, nil
-}
-
-func copyFieldElement(buf *[32]byte, v *field.Element) []byte {
-	copy(buf[:], v.Bytes())
-	return buf[:]
-}
-
-// Conversions.
-
-func (v *projP2) FromP1xP1(p *projP1xP1) *projP2 {
-	v.X.Multiply(&p.X, &p.T)
-	v.Y.Multiply(&p.Y, &p.Z)
-	v.Z.Multiply(&p.Z, &p.T)
-	return v
-}
-
-func (v *projP2) FromP3(p *Point) *projP2 {
-	v.X.Set(&p.x)
-	v.Y.Set(&p.y)
-	v.Z.Set(&p.z)
-	return v
-}
-
-func (v *Point) fromP1xP1(p *projP1xP1) *Point {
-	v.x.Multiply(&p.X, &p.T)
-	v.y.Multiply(&p.Y, &p.Z)
-	v.z.Multiply(&p.Z, &p.T)
-	v.t.Multiply(&p.X, &p.Y)
-	return v
-}
-
-func (v *Point) fromP2(p *projP2) *Point {
-	v.x.Multiply(&p.X, &p.Z)
-	v.y.Multiply(&p.Y, &p.Z)
-	v.z.Square(&p.Z)
-	v.t.Multiply(&p.X, &p.Y)
-	return v
-}
-
-// d is a constant in the curve equation.
-var d = new(field.Element).SetBytes([]byte{
-	0xa3, 0x78, 0x59, 0x13, 0xca, 0x4d, 0xeb, 0x75,
-	0xab, 0xd8, 0x41, 0x41, 0x4d, 0x0a, 0x70, 0x00,
-	0x98, 0xe8, 0x79, 0x77, 0x79, 0x40, 0xc7, 0x8c,
-	0x73, 0xfe, 0x6f, 0x2b, 0xee, 0x6c, 0x03, 0x52})
-var d2 = new(field.Element).Add(d, d)
-
-func (v *projCached) FromP3(p *Point) *projCached {
-	v.YplusX.Add(&p.y, &p.x)
-	v.YminusX.Subtract(&p.y, &p.x)
-	v.Z.Set(&p.z)
-	v.T2d.Multiply(&p.t, d2)
-	return v
-}
-
-func (v *affineCached) FromP3(p *Point) *affineCached {
-	v.YplusX.Add(&p.y, &p.x)
-	v.YminusX.Subtract(&p.y, &p.x)
-	v.T2d.Multiply(&p.t, d2)
-
-	var invZ field.Element
-	invZ.Invert(&p.z)
-	v.YplusX.Multiply(&v.YplusX, &invZ)
-	v.YminusX.Multiply(&v.YminusX, &invZ)
-	v.T2d.Multiply(&v.T2d, &invZ)
-	return v
-}
-
-// (Re)addition and subtraction.
-
-// Add sets v = p + q, and returns v.
-func (v *Point) Add(p, q *Point) *Point {
-	checkInitialized(p, q)
-	qCached := new(projCached).FromP3(q)
-	result := new(projP1xP1).Add(p, qCached)
-	return v.fromP1xP1(result)
-}
-
-// Subtract sets v = p - q, and returns v.
-func (v *Point) Subtract(p, q *Point) *Point {
-	checkInitialized(p, q)
-	qCached := new(projCached).FromP3(q)
-	result := new(projP1xP1).Sub(p, qCached)
-	return v.fromP1xP1(result)
-}
-
-func (v *projP1xP1) Add(p *Point, q *projCached) *projP1xP1 {
-	var YplusX, YminusX, PP, MM, TT2d, ZZ2 field.Element
-
-	YplusX.Add(&p.y, &p.x)
-	YminusX.Subtract(&p.y, &p.x)
-
-	PP.Multiply(&YplusX, &q.YplusX)
-	MM.Multiply(&YminusX, &q.YminusX)
-	TT2d.Multiply(&p.t, &q.T2d)
-	ZZ2.Multiply(&p.z, &q.Z)
-
-	ZZ2.Add(&ZZ2, &ZZ2)
-
-	v.X.Subtract(&PP, &MM)
-	v.Y.Add(&PP, &MM)
-	v.Z.Add(&ZZ2, &TT2d)
-	v.T.Subtract(&ZZ2, &TT2d)
-	return v
-}
-
-func (v *projP1xP1) Sub(p *Point, q *projCached) *projP1xP1 {
-	var YplusX, YminusX, PP, MM, TT2d, ZZ2 field.Element
-
-	YplusX.Add(&p.y, &p.x)
-	YminusX.Subtract(&p.y, &p.x)
-
-	PP.Multiply(&YplusX, &q.YminusX) // flipped sign
-	MM.Multiply(&YminusX, &q.YplusX) // flipped sign
-	TT2d.Multiply(&p.t, &q.T2d)
-	ZZ2.Multiply(&p.z, &q.Z)
-
-	ZZ2.Add(&ZZ2, &ZZ2)
-
-	v.X.Subtract(&PP, &MM)
-	v.Y.Add(&PP, &MM)
-	v.Z.Subtract(&ZZ2, &TT2d) // flipped sign
-	v.T.Add(&ZZ2, &TT2d)      // flipped sign
-	return v
-}
-
-func (v *projP1xP1) AddAffine(p *Point, q *affineCached) *projP1xP1 {
-	var YplusX, YminusX, PP, MM, TT2d, Z2 field.Element
-
-	YplusX.Add(&p.y, &p.x)
-	YminusX.Subtract(&p.y, &p.x)
-
-	PP.Multiply(&YplusX, &q.YplusX)
-	MM.Multiply(&YminusX, &q.YminusX)
-	TT2d.Multiply(&p.t, &q.T2d)
-
-	Z2.Add(&p.z, &p.z)
-
-	v.X.Subtract(&PP, &MM)
-	v.Y.Add(&PP, &MM)
-	v.Z.Add(&Z2, &TT2d)
-	v.T.Subtract(&Z2, &TT2d)
-	return v
-}
-
-func (v *projP1xP1) SubAffine(p *Point, q *affineCached) *projP1xP1 {
-	var YplusX, YminusX, PP, MM, TT2d, Z2 field.Element
-
-	YplusX.Add(&p.y, &p.x)
-	YminusX.Subtract(&p.y, &p.x)
-
-	PP.Multiply(&YplusX, &q.YminusX) // flipped sign
-	MM.Multiply(&YminusX, &q.YplusX) // flipped sign
-	TT2d.Multiply(&p.t, &q.T2d)
-
-	Z2.Add(&p.z, &p.z)
-
-	v.X.Subtract(&PP, &MM)
-	v.Y.Add(&PP, &MM)
-	v.Z.Subtract(&Z2, &TT2d) // flipped sign
-	v.T.Add(&Z2, &TT2d)      // flipped sign
-	return v
-}
-
-// Doubling.
-
-func (v *projP1xP1) Double(p *projP2) *projP1xP1 {
-	var XX, YY, ZZ2, XplusYsq field.Element
-
-	XX.Square(&p.X)
-	YY.Square(&p.Y)
-	ZZ2.Square(&p.Z)
-	ZZ2.Add(&ZZ2, &ZZ2)
-	XplusYsq.Add(&p.X, &p.Y)
-	XplusYsq.Square(&XplusYsq)
-
-	v.Y.Add(&YY, &XX)
-	v.Z.Subtract(&YY, &XX)
-
-	v.X.Subtract(&XplusYsq, &v.Y)
-	v.T.Subtract(&ZZ2, &v.Z)
-	return v
-}
-
-// Negation.
-
-// Negate sets v = -p, and returns v.
-func (v *Point) Negate(p *Point) *Point {
-	checkInitialized(p)
-	v.x.Negate(&p.x)
-	v.y.Set(&p.y)
-	v.z.Set(&p.z)
-	v.t.Negate(&p.t)
-	return v
-}
-
-// Equal returns 1 if v is equivalent to u, and 0 otherwise.
-func (v *Point) Equal(u *Point) int {
-	checkInitialized(v, u)
-
-	var t1, t2, t3, t4 field.Element
-	t1.Multiply(&v.x, &u.z)
-	t2.Multiply(&u.x, &v.z)
-	t3.Multiply(&v.y, &u.z)
-	t4.Multiply(&u.y, &v.z)
-
-	return t1.Equal(&t2) & t3.Equal(&t4)
-}
-
-// Constant-time operations
-
-// Select sets v to a if cond == 1 and to b if cond == 0.
-func (v *projCached) Select(a, b *projCached, cond int) *projCached {
-	v.YplusX.Select(&a.YplusX, &b.YplusX, cond)
-	v.YminusX.Select(&a.YminusX, &b.YminusX, cond)
-	v.Z.Select(&a.Z, &b.Z, cond)
-	v.T2d.Select(&a.T2d, &b.T2d, cond)
-	return v
-}
-
-// Select sets v to a if cond == 1 and to b if cond == 0.
-func (v *affineCached) Select(a, b *affineCached, cond int) *affineCached {
-	v.YplusX.Select(&a.YplusX, &b.YplusX, cond)
-	v.YminusX.Select(&a.YminusX, &b.YminusX, cond)
-	v.T2d.Select(&a.T2d, &b.T2d, cond)
-	return v
-}
-
-// CondNeg negates v if cond == 1 and leaves it unchanged if cond == 0.
-func (v *projCached) CondNeg(cond int) *projCached {
-	v.YplusX.Swap(&v.YminusX, cond)
-	v.T2d.Select(new(field.Element).Negate(&v.T2d), &v.T2d, cond)
-	return v
-}
-
-// CondNeg negates v if cond == 1 and leaves it unchanged if cond == 0.
-func (v *affineCached) CondNeg(cond int) *affineCached {
-	v.YplusX.Swap(&v.YminusX, cond)
-	v.T2d.Select(new(field.Element).Negate(&v.T2d), &v.T2d, cond)
-	return v
-}
diff --git a/contrib/go/_std_1.18/src/crypto/ed25519/internal/edwards25519/field/fe.go b/contrib/go/_std_1.18/src/crypto/ed25519/internal/edwards25519/field/fe.go
deleted file mode 100644
index dbe86599b3..0000000000
--- a/contrib/go/_std_1.18/src/crypto/ed25519/internal/edwards25519/field/fe.go
+++ /dev/null
@@ -1,416 +0,0 @@
-// Copyright (c) 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package field implements fast arithmetic modulo 2^255-19.
-package field
-
-import (
-	"crypto/subtle"
-	"encoding/binary"
-	"math/bits"
-)
-
-// Element represents an element of the field GF(2^255-19). Note that this
-// is not a cryptographically secure group, and should only be used to interact
-// with edwards25519.Point coordinates.
-//
-// This type works similarly to math/big.Int, and all arguments and receivers
-// are allowed to alias.
-//
-// The zero value is a valid zero element.
-type Element struct {
-	// An element t represents the integer
-	//     t.l0 + t.l1*2^51 + t.l2*2^102 + t.l3*2^153 + t.l4*2^204
-	//
-	// Between operations, all limbs are expected to be lower than 2^52.
-	l0 uint64
-	l1 uint64
-	l2 uint64
-	l3 uint64
-	l4 uint64
-}
-
-const maskLow51Bits uint64 = (1 << 51) - 1
-
-var feZero = &Element{0, 0, 0, 0, 0}
-
-// Zero sets v = 0, and returns v.
-func (v *Element) Zero() *Element {
-	*v = *feZero
-	return v
-}
-
-var feOne = &Element{1, 0, 0, 0, 0}
-
-// One sets v = 1, and returns v.
-func (v *Element) One() *Element {
-	*v = *feOne
-	return v
-}
-
-// reduce reduces v modulo 2^255 - 19 and returns it.
-func (v *Element) reduce() *Element {
-	v.carryPropagate()
-
-	// After the light reduction we now have a field element representation
-	// v < 2^255 + 2^13 * 19, but need v < 2^255 - 19.
-
-	// If v >= 2^255 - 19, then v + 19 >= 2^255, which would overflow 2^255 - 1,
-	// generating a carry. That is, c will be 0 if v < 2^255 - 19, and 1 otherwise.
-	c := (v.l0 + 19) >> 51
-	c = (v.l1 + c) >> 51
-	c = (v.l2 + c) >> 51
-	c = (v.l3 + c) >> 51
-	c = (v.l4 + c) >> 51
-
-	// If v < 2^255 - 19 and c = 0, this will be a no-op. Otherwise, it's
-	// effectively applying the reduction identity to the carry.
-	v.l0 += 19 * c
-
-	v.l1 += v.l0 >> 51
-	v.l0 = v.l0 & maskLow51Bits
-	v.l2 += v.l1 >> 51
-	v.l1 = v.l1 & maskLow51Bits
-	v.l3 += v.l2 >> 51
-	v.l2 = v.l2 & maskLow51Bits
-	v.l4 += v.l3 >> 51
-	v.l3 = v.l3 & maskLow51Bits
-	// no additional carry
-	v.l4 = v.l4 & maskLow51Bits
-
-	return v
-}
-
-// Add sets v = a + b, and returns v.
-func (v *Element) Add(a, b *Element) *Element {
-	v.l0 = a.l0 + b.l0
-	v.l1 = a.l1 + b.l1
-	v.l2 = a.l2 + b.l2
-	v.l3 = a.l3 + b.l3
-	v.l4 = a.l4 + b.l4
-	// Using the generic implementation here is actually faster than the
-	// assembly. Probably because the body of this function is so simple that
-	// the compiler can figure out better optimizations by inlining the carry
-	// propagation.
-	return v.carryPropagateGeneric()
-}
-
-// Subtract sets v = a - b, and returns v.
-func (v *Element) Subtract(a, b *Element) *Element {
-	// We first add 2 * p, to guarantee the subtraction won't underflow, and
-	// then subtract b (which can be up to 2^255 + 2^13 * 19).
-	v.l0 = (a.l0 + 0xFFFFFFFFFFFDA) - b.l0
-	v.l1 = (a.l1 + 0xFFFFFFFFFFFFE) - b.l1
-	v.l2 = (a.l2 + 0xFFFFFFFFFFFFE) - b.l2
-	v.l3 = (a.l3 + 0xFFFFFFFFFFFFE) - b.l3
-	v.l4 = (a.l4 + 0xFFFFFFFFFFFFE) - b.l4
-	return v.carryPropagate()
-}
-
-// Negate sets v = -a, and returns v.
-func (v *Element) Negate(a *Element) *Element {
-	return v.Subtract(feZero, a)
-}
-
-// Invert sets v = 1/z mod p, and returns v.
-//
-// If z == 0, Invert returns v = 0.
-func (v *Element) Invert(z *Element) *Element {
-	// Inversion is implemented as exponentiation with exponent p − 2. It uses the
-	// same sequence of 255 squarings and 11 multiplications as [Curve25519].
-	var z2, z9, z11, z2_5_0, z2_10_0, z2_20_0, z2_50_0, z2_100_0, t Element
-
-	z2.Square(z)             // 2
-	t.Square(&z2)            // 4
-	t.Square(&t)             // 8
-	z9.Multiply(&t, z)       // 9
-	z11.Multiply(&z9, &z2)   // 11
-	t.Square(&z11)           // 22
-	z2_5_0.Multiply(&t, &z9) // 31 = 2^5 - 2^0
-
-	t.Square(&z2_5_0) // 2^6 - 2^1
-	for i := 0; i < 4; i++ {
-		t.Square(&t) // 2^10 - 2^5
-	}
-	z2_10_0.Multiply(&t, &z2_5_0) // 2^10 - 2^0
-
-	t.Square(&z2_10_0) // 2^11 - 2^1
-	for i := 0; i < 9; i++ {
-		t.Square(&t) // 2^20 - 2^10
-	}
-	z2_20_0.Multiply(&t, &z2_10_0) // 2^20 - 2^0
-
-	t.Square(&z2_20_0) // 2^21 - 2^1
-	for i := 0; i < 19; i++ {
-		t.Square(&t) // 2^40 - 2^20
-	}
-	t.Multiply(&t, &z2_20_0) // 2^40 - 2^0
-
-	t.Square(&t) // 2^41 - 2^1
-	for i := 0; i < 9; i++ {
-		t.Square(&t) // 2^50 - 2^10
-	}
-	z2_50_0.Multiply(&t, &z2_10_0) // 2^50 - 2^0
-
-	t.Square(&z2_50_0) // 2^51 - 2^1
-	for i := 0; i < 49; i++ {
-		t.Square(&t) // 2^100 - 2^50
-	}
-	z2_100_0.Multiply(&t, &z2_50_0) // 2^100 - 2^0
-
-	t.Square(&z2_100_0) // 2^101 - 2^1
-	for i := 0; i < 99; i++ {
-		t.Square(&t) // 2^200 - 2^100
-	}
-	t.Multiply(&t, &z2_100_0) // 2^200 - 2^0
-
-	t.Square(&t) // 2^201 - 2^1
-	for i := 0; i < 49; i++ {
-		t.Square(&t) // 2^250 - 2^50
-	}
-	t.Multiply(&t, &z2_50_0) // 2^250 - 2^0
-
-	t.Square(&t) // 2^251 - 2^1
-	t.Square(&t) // 2^252 - 2^2
-	t.Square(&t) // 2^253 - 2^3
-	t.Square(&t) // 2^254 - 2^4
-	t.Square(&t) // 2^255 - 2^5
-
-	return v.Multiply(&t, &z11) // 2^255 - 21
-}
-
-// Set sets v = a, and returns v.
-func (v *Element) Set(a *Element) *Element {
-	*v = *a
-	return v
-}
-
-// SetBytes sets v to x, which must be a 32-byte little-endian encoding.
-//
-// Consistent with RFC 7748, the most significant bit (the high bit of the
-// last byte) is ignored, and non-canonical values (2^255-19 through 2^255-1)
-// are accepted. Note that this is laxer than specified by RFC 8032.
-func (v *Element) SetBytes(x []byte) *Element {
-	if len(x) != 32 {
-		panic("edwards25519: invalid field element input size")
-	}
-
-	// Bits 0:51 (bytes 0:8, bits 0:64, shift 0, mask 51).
-	v.l0 = binary.LittleEndian.Uint64(x[0:8])
-	v.l0 &= maskLow51Bits
-	// Bits 51:102 (bytes 6:14, bits 48:112, shift 3, mask 51).
-	v.l1 = binary.LittleEndian.Uint64(x[6:14]) >> 3
-	v.l1 &= maskLow51Bits
-	// Bits 102:153 (bytes 12:20, bits 96:160, shift 6, mask 51).
-	v.l2 = binary.LittleEndian.Uint64(x[12:20]) >> 6
-	v.l2 &= maskLow51Bits
-	// Bits 153:204 (bytes 19:27, bits 152:216, shift 1, mask 51).
-	v.l3 = binary.LittleEndian.Uint64(x[19:27]) >> 1
-	v.l3 &= maskLow51Bits
-	// Bits 204:251 (bytes 24:32, bits 192:256, shift 12, mask 51).
-	// Note: not bytes 25:33, shift 4, to avoid overread.
-	v.l4 = binary.LittleEndian.Uint64(x[24:32]) >> 12
-	v.l4 &= maskLow51Bits
-
-	return v
-}
-
-// Bytes returns the canonical 32-byte little-endian encoding of v.
-func (v *Element) Bytes() []byte {
-	// This function is outlined to make the allocations inline in the caller
-	// rather than happen on the heap.
-	var out [32]byte
-	return v.bytes(&out)
-}
-
-func (v *Element) bytes(out *[32]byte) []byte {
-	t := *v
-	t.reduce()
-
-	var buf [8]byte
-	for i, l := range [5]uint64{t.l0, t.l1, t.l2, t.l3, t.l4} {
-		bitsOffset := i * 51
-		binary.LittleEndian.PutUint64(buf[:], l<<uint(bitsOffset%8))
-		for i, bb := range buf {
-			off := bitsOffset/8 + i
-			if off >= len(out) {
-				break
-			}
-			out[off] |= bb
-		}
-	}
-
-	return out[:]
-}
-
-// Equal returns 1 if v and u are equal, and 0 otherwise.
-func (v *Element) Equal(u *Element) int {
-	sa, sv := u.Bytes(), v.Bytes()
-	return subtle.ConstantTimeCompare(sa, sv)
-}
-
-// mask64Bits returns 0xffffffff if cond is 1, and 0 otherwise.
-func mask64Bits(cond int) uint64 { return ^(uint64(cond) - 1) }
-
-// Select sets v to a if cond == 1, and to b if cond == 0.
-func (v *Element) Select(a, b *Element, cond int) *Element {
-	m := mask64Bits(cond)
-	v.l0 = (m & a.l0) | (^m & b.l0)
-	v.l1 = (m & a.l1) | (^m & b.l1)
-	v.l2 = (m & a.l2) | (^m & b.l2)
-	v.l3 = (m & a.l3) | (^m & b.l3)
-	v.l4 = (m & a.l4) | (^m & b.l4)
-	return v
-}
-
-// Swap swaps v and u if cond == 1 or leaves them unchanged if cond == 0, and returns v.
-func (v *Element) Swap(u *Element, cond int) {
-	m := mask64Bits(cond)
-	t := m & (v.l0 ^ u.l0)
-	v.l0 ^= t
-	u.l0 ^= t
-	t = m & (v.l1 ^ u.l1)
-	v.l1 ^= t
-	u.l1 ^= t
-	t = m & (v.l2 ^ u.l2)
-	v.l2 ^= t
-	u.l2 ^= t
-	t = m & (v.l3 ^ u.l3)
-	v.l3 ^= t
-	u.l3 ^= t
-	t = m & (v.l4 ^ u.l4)
-	v.l4 ^= t
-	u.l4 ^= t
-}
-
-// IsNegative returns 1 if v is negative, and 0 otherwise.
-func (v *Element) IsNegative() int {
-	return int(v.Bytes()[0] & 1)
-}
-
-// Absolute sets v to |u|, and returns v.
-func (v *Element) Absolute(u *Element) *Element {
-	return v.Select(new(Element).Negate(u), u, u.IsNegative())
-}
-
-// Multiply sets v = x * y, and returns v.
-func (v *Element) Multiply(x, y *Element) *Element {
-	feMul(v, x, y)
-	return v
-}
-
-// Square sets v = x * x, and returns v.
-func (v *Element) Square(x *Element) *Element {
-	feSquare(v, x)
-	return v
-}
-
-// Mult32 sets v = x * y, and returns v.
-func (v *Element) Mult32(x *Element, y uint32) *Element {
-	x0lo, x0hi := mul51(x.l0, y)
-	x1lo, x1hi := mul51(x.l1, y)
-	x2lo, x2hi := mul51(x.l2, y)
-	x3lo, x3hi := mul51(x.l3, y)
-	x4lo, x4hi := mul51(x.l4, y)
-	v.l0 = x0lo + 19*x4hi // carried over per the reduction identity
-	v.l1 = x1lo + x0hi
-	v.l2 = x2lo + x1hi
-	v.l3 = x3lo + x2hi
-	v.l4 = x4lo + x3hi
-	// The hi portions are going to be only 32 bits, plus any previous excess,
-	// so we can skip the carry propagation.
-	return v
-}
-
-// mul51 returns lo + hi * 2⁵¹ = a * b.
-func mul51(a uint64, b uint32) (lo uint64, hi uint64) {
-	mh, ml := bits.Mul64(a, uint64(b))
-	lo = ml & maskLow51Bits
-	hi = (mh << 13) | (ml >> 51)
-	return
-}
-
-// Pow22523 set v = x^((p-5)/8), and returns v. (p-5)/8 is 2^252-3.
-func (v *Element) Pow22523(x *Element) *Element {
-	var t0, t1, t2 Element
-
-	t0.Square(x)             // x^2
-	t1.Square(&t0)           // x^4
-	t1.Square(&t1)           // x^8
-	t1.Multiply(x, &t1)      // x^9
-	t0.Multiply(&t0, &t1)    // x^11
-	t0.Square(&t0)           // x^22
-	t0.Multiply(&t1, &t0)    // x^31
-	t1.Square(&t0)           // x^62
-	for i := 1; i < 5; i++ { // x^992
-		t1.Square(&t1)
-	}
-	t0.Multiply(&t1, &t0)     // x^1023 -> 1023 = 2^10 - 1
-	t1.Square(&t0)            // 2^11 - 2
-	for i := 1; i < 10; i++ { // 2^20 - 2^10
-		t1.Square(&t1)
-	}
-	t1.Multiply(&t1, &t0)     // 2^20 - 1
-	t2.Square(&t1)            // 2^21 - 2
-	for i := 1; i < 20; i++ { // 2^40 - 2^20
-		t2.Square(&t2)
-	}
-	t1.Multiply(&t2, &t1)     // 2^40 - 1
-	t1.Square(&t1)            // 2^41 - 2
-	for i := 1; i < 10; i++ { // 2^50 - 2^10
-		t1.Square(&t1)
-	}
-	t0.Multiply(&t1, &t0)     // 2^50 - 1
-	t1.Square(&t0)            // 2^51 - 2
-	for i := 1; i < 50; i++ { // 2^100 - 2^50
-		t1.Square(&t1)
-	}
-	t1.Multiply(&t1, &t0)      // 2^100 - 1
-	t2.Square(&t1)             // 2^101 - 2
-	for i := 1; i < 100; i++ { // 2^200 - 2^100
-		t2.Square(&t2)
-	}
-	t1.Multiply(&t2, &t1)     // 2^200 - 1
-	t1.Square(&t1)            // 2^201 - 2
-	for i := 1; i < 50; i++ { // 2^250 - 2^50
-		t1.Square(&t1)
-	}
-	t0.Multiply(&t1, &t0)     // 2^250 - 1
-	t0.Square(&t0)            // 2^251 - 2
-	t0.Square(&t0)            // 2^252 - 4
-	return v.Multiply(&t0, x) // 2^252 - 3 -> x^(2^252-3)
-}
-
-// sqrtM1 is 2^((p-1)/4), which squared is equal to -1 by Euler's Criterion.
-var sqrtM1 = &Element{1718705420411056, 234908883556509,
-	2233514472574048, 2117202627021982, 765476049583133}
-
-// SqrtRatio sets r to the non-negative square root of the ratio of u and v.
-//
-// If u/v is square, SqrtRatio returns r and 1. If u/v is not square, SqrtRatio
-// sets r according to Section 4.3 of draft-irtf-cfrg-ristretto255-decaf448-00,
-// and returns r and 0.
-func (r *Element) SqrtRatio(u, v *Element) (rr *Element, wasSquare int) {
-	var a, b Element
-
-	// r = (u * v3) * (u * v7)^((p-5)/8)
-	v2 := a.Square(v)
-	uv3 := b.Multiply(u, b.Multiply(v2, v))
-	uv7 := a.Multiply(uv3, a.Square(v2))
-	r.Multiply(uv3, r.Pow22523(uv7))
-
-	check := a.Multiply(v, a.Square(r)) // check = v * r^2
-
-	uNeg := b.Negate(u)
-	correctSignSqrt := check.Equal(u)
-	flippedSignSqrt := check.Equal(uNeg)
-	flippedSignSqrtI := check.Equal(uNeg.Multiply(uNeg, sqrtM1))
-
-	rPrime := b.Multiply(r, sqrtM1) // r_prime = SQRT_M1 * r
-	// r = CT_SELECT(r_prime IF flipped_sign_sqrt | flipped_sign_sqrt_i ELSE r)
-	r.Select(rPrime, r, flippedSignSqrt|flippedSignSqrtI)
-
-	r.Absolute(r) // Choose the nonnegative square root.
-	return r, correctSignSqrt | flippedSignSqrt
-}
diff --git a/contrib/go/_std_1.18/src/crypto/ed25519/internal/edwards25519/field/fe_amd64.go b/contrib/go/_std_1.18/src/crypto/ed25519/internal/edwards25519/field/fe_amd64.go
deleted file mode 100644
index 363020bd6b..0000000000
--- a/contrib/go/_std_1.18/src/crypto/ed25519/internal/edwards25519/field/fe_amd64.go
+++ /dev/null
@@ -1,13 +0,0 @@
-// Code generated by command: go run fe_amd64_asm.go -out ../fe_amd64.s -stubs ../fe_amd64.go -pkg field. DO NOT EDIT.
-
-//go:build amd64 && gc && !purego
-
-package field
-
-// feMul sets out = a * b. It works like feMulGeneric.
-//go:noescape
-func feMul(out *Element, a *Element, b *Element)
-
-// feSquare sets out = a * a. It works like feSquareGeneric.
-//go:noescape
-func feSquare(out *Element, a *Element)
diff --git a/contrib/go/_std_1.18/src/crypto/ed25519/internal/edwards25519/field/fe_generic.go b/contrib/go/_std_1.18/src/crypto/ed25519/internal/edwards25519/field/fe_generic.go
deleted file mode 100644
index bccf8511ac..0000000000
--- a/contrib/go/_std_1.18/src/crypto/ed25519/internal/edwards25519/field/fe_generic.go
+++ /dev/null
@@ -1,264 +0,0 @@
-// Copyright (c) 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package field
-
-import "math/bits"
-
-// uint128 holds a 128-bit number as two 64-bit limbs, for use with the
-// bits.Mul64 and bits.Add64 intrinsics.
-type uint128 struct {
-	lo, hi uint64
-}
-
-// mul64 returns a * b.
-func mul64(a, b uint64) uint128 {
-	hi, lo := bits.Mul64(a, b)
-	return uint128{lo, hi}
-}
-
-// addMul64 returns v + a * b.
-func addMul64(v uint128, a, b uint64) uint128 {
-	hi, lo := bits.Mul64(a, b)
-	lo, c := bits.Add64(lo, v.lo, 0)
-	hi, _ = bits.Add64(hi, v.hi, c)
-	return uint128{lo, hi}
-}
-
-// shiftRightBy51 returns a >> 51. a is assumed to be at most 115 bits.
-func shiftRightBy51(a uint128) uint64 {
-	return (a.hi << (64 - 51)) | (a.lo >> 51)
-}
-
-func feMulGeneric(v, a, b *Element) {
-	a0 := a.l0
-	a1 := a.l1
-	a2 := a.l2
-	a3 := a.l3
-	a4 := a.l4
-
-	b0 := b.l0
-	b1 := b.l1
-	b2 := b.l2
-	b3 := b.l3
-	b4 := b.l4
-
-	// Limb multiplication works like pen-and-paper columnar multiplication, but
-	// with 51-bit limbs instead of digits.
-	//
-	//                          a4   a3   a2   a1   a0  x
-	//                          b4   b3   b2   b1   b0  =
-	//                         ------------------------
-	//                        a4b0 a3b0 a2b0 a1b0 a0b0  +
-	//                   a4b1 a3b1 a2b1 a1b1 a0b1       +
-	//              a4b2 a3b2 a2b2 a1b2 a0b2            +
-	//         a4b3 a3b3 a2b3 a1b3 a0b3                 +
-	//    a4b4 a3b4 a2b4 a1b4 a0b4                      =
-	//   ----------------------------------------------
-	//      r8   r7   r6   r5   r4   r3   r2   r1   r0
-	//
-	// We can then use the reduction identity (a * 2²⁵⁵ + b = a * 19 + b) to
-	// reduce the limbs that would overflow 255 bits. r5 * 2²⁵⁵ becomes 19 * r5,
-	// r6 * 2³⁰⁶ becomes 19 * r6 * 2⁵¹, etc.
-	//
-	// Reduction can be carried out simultaneously to multiplication. For
-	// example, we do not compute r5: whenever the result of a multiplication
-	// belongs to r5, like a1b4, we multiply it by 19 and add the result to r0.
-	//
-	//            a4b0    a3b0    a2b0    a1b0    a0b0  +
-	//            a3b1    a2b1    a1b1    a0b1 19×a4b1  +
-	//            a2b2    a1b2    a0b2 19×a4b2 19×a3b2  +
-	//            a1b3    a0b3 19×a4b3 19×a3b3 19×a2b3  +
-	//            a0b4 19×a4b4 19×a3b4 19×a2b4 19×a1b4  =
-	//           --------------------------------------
-	//              r4      r3      r2      r1      r0
-	//
-	// Finally we add up the columns into wide, overlapping limbs.
-
-	a1_19 := a1 * 19
-	a2_19 := a2 * 19
-	a3_19 := a3 * 19
-	a4_19 := a4 * 19
-
-	// r0 = a0×b0 + 19×(a1×b4 + a2×b3 + a3×b2 + a4×b1)
-	r0 := mul64(a0, b0)
-	r0 = addMul64(r0, a1_19, b4)
-	r0 = addMul64(r0, a2_19, b3)
-	r0 = addMul64(r0, a3_19, b2)
-	r0 = addMul64(r0, a4_19, b1)
-
-	// r1 = a0×b1 + a1×b0 + 19×(a2×b4 + a3×b3 + a4×b2)
-	r1 := mul64(a0, b1)
-	r1 = addMul64(r1, a1, b0)
-	r1 = addMul64(r1, a2_19, b4)
-	r1 = addMul64(r1, a3_19, b3)
-	r1 = addMul64(r1, a4_19, b2)
-
-	// r2 = a0×b2 + a1×b1 + a2×b0 + 19×(a3×b4 + a4×b3)
-	r2 := mul64(a0, b2)
-	r2 = addMul64(r2, a1, b1)
-	r2 = addMul64(r2, a2, b0)
-	r2 = addMul64(r2, a3_19, b4)
-	r2 = addMul64(r2, a4_19, b3)
-
-	// r3 = a0×b3 + a1×b2 + a2×b1 + a3×b0 + 19×a4×b4
-	r3 := mul64(a0, b3)
-	r3 = addMul64(r3, a1, b2)
-	r3 = addMul64(r3, a2, b1)
-	r3 = addMul64(r3, a3, b0)
-	r3 = addMul64(r3, a4_19, b4)
-
-	// r4 = a0×b4 + a1×b3 + a2×b2 + a3×b1 + a4×b0
-	r4 := mul64(a0, b4)
-	r4 = addMul64(r4, a1, b3)
-	r4 = addMul64(r4, a2, b2)
-	r4 = addMul64(r4, a3, b1)
-	r4 = addMul64(r4, a4, b0)
-
-	// After the multiplication, we need to reduce (carry) the five coefficients
-	// to obtain a result with limbs that are at most slightly larger than 2⁵¹,
-	// to respect the Element invariant.
-	//
-	// Overall, the reduction works the same as carryPropagate, except with
-	// wider inputs: we take the carry for each coefficient by shifting it right
-	// by 51, and add it to the limb above it. The top carry is multiplied by 19
-	// according to the reduction identity and added to the lowest limb.
-	//
-	// The largest coefficient (r0) will be at most 111 bits, which guarantees
-	// that all carries are at most 111 - 51 = 60 bits, which fits in a uint64.
-	//
-	//     r0 = a0×b0 + 19×(a1×b4 + a2×b3 + a3×b2 + a4×b1)
-	//     r0 < 2⁵²×2⁵² + 19×(2⁵²×2⁵² + 2⁵²×2⁵² + 2⁵²×2⁵² + 2⁵²×2⁵²)
-	//     r0 < (1 + 19 × 4) × 2⁵² × 2⁵²
-	//     r0 < 2⁷ × 2⁵² × 2⁵²
-	//     r0 < 2¹¹¹
-	//
-	// Moreover, the top coefficient (r4) is at most 107 bits, so c4 is at most
-	// 56 bits, and c4 * 19 is at most 61 bits, which again fits in a uint64 and
-	// allows us to easily apply the reduction identity.
-	//
-	//     r4 = a0×b4 + a1×b3 + a2×b2 + a3×b1 + a4×b0
-	//     r4 < 5 × 2⁵² × 2⁵²
-	//     r4 < 2¹⁰⁷
-	//
-
-	c0 := shiftRightBy51(r0)
-	c1 := shiftRightBy51(r1)
-	c2 := shiftRightBy51(r2)
-	c3 := shiftRightBy51(r3)
-	c4 := shiftRightBy51(r4)
-
-	rr0 := r0.lo&maskLow51Bits + c4*19
-	rr1 := r1.lo&maskLow51Bits + c0
-	rr2 := r2.lo&maskLow51Bits + c1
-	rr3 := r3.lo&maskLow51Bits + c2
-	rr4 := r4.lo&maskLow51Bits + c3
-
-	// Now all coefficients fit into 64-bit registers but are still too large to
-	// be passed around as a Element. We therefore do one last carry chain,
-	// where the carries will be small enough to fit in the wiggle room above 2⁵¹.
-	*v = Element{rr0, rr1, rr2, rr3, rr4}
-	v.carryPropagate()
-}
-
-func feSquareGeneric(v, a *Element) {
-	l0 := a.l0
-	l1 := a.l1
-	l2 := a.l2
-	l3 := a.l3
-	l4 := a.l4
-
-	// Squaring works precisely like multiplication above, but thanks to its
-	// symmetry we get to group a few terms together.
-	//
-	//                          l4   l3   l2   l1   l0  x
-	//                          l4   l3   l2   l1   l0  =
-	//                         ------------------------
-	//                        l4l0 l3l0 l2l0 l1l0 l0l0  +
-	//                   l4l1 l3l1 l2l1 l1l1 l0l1       +
-	//              l4l2 l3l2 l2l2 l1l2 l0l2            +
-	//         l4l3 l3l3 l2l3 l1l3 l0l3                 +
-	//    l4l4 l3l4 l2l4 l1l4 l0l4                      =
-	//   ----------------------------------------------
-	//      r8   r7   r6   r5   r4   r3   r2   r1   r0
-	//
-	//            l4l0    l3l0    l2l0    l1l0    l0l0  +
-	//            l3l1    l2l1    l1l1    l0l1 19×l4l1  +
-	//            l2l2    l1l2    l0l2 19×l4l2 19×l3l2  +
-	//            l1l3    l0l3 19×l4l3 19×l3l3 19×l2l3  +
-	//            l0l4 19×l4l4 19×l3l4 19×l2l4 19×l1l4  =
-	//           --------------------------------------
-	//              r4      r3      r2      r1      r0
-	//
-	// With precomputed 2×, 19×, and 2×19× terms, we can compute each limb with
-	// only three Mul64 and four Add64, instead of five and eight.
-
-	l0_2 := l0 * 2
-	l1_2 := l1 * 2
-
-	l1_38 := l1 * 38
-	l2_38 := l2 * 38
-	l3_38 := l3 * 38
-
-	l3_19 := l3 * 19
-	l4_19 := l4 * 19
-
-	// r0 = l0×l0 + 19×(l1×l4 + l2×l3 + l3×l2 + l4×l1) = l0×l0 + 19×2×(l1×l4 + l2×l3)
-	r0 := mul64(l0, l0)
-	r0 = addMul64(r0, l1_38, l4)
-	r0 = addMul64(r0, l2_38, l3)
-
-	// r1 = l0×l1 + l1×l0 + 19×(l2×l4 + l3×l3 + l4×l2) = 2×l0×l1 + 19×2×l2×l4 + 19×l3×l3
-	r1 := mul64(l0_2, l1)
-	r1 = addMul64(r1, l2_38, l4)
-	r1 = addMul64(r1, l3_19, l3)
-
-	// r2 = l0×l2 + l1×l1 + l2×l0 + 19×(l3×l4 + l4×l3) = 2×l0×l2 + l1×l1 + 19×2×l3×l4
-	r2 := mul64(l0_2, l2)
-	r2 = addMul64(r2, l1, l1)
-	r2 = addMul64(r2, l3_38, l4)
-
-	// r3 = l0×l3 + l1×l2 + l2×l1 + l3×l0 + 19×l4×l4 = 2×l0×l3 + 2×l1×l2 + 19×l4×l4
-	r3 := mul64(l0_2, l3)
-	r3 = addMul64(r3, l1_2, l2)
-	r3 = addMul64(r3, l4_19, l4)
-
-	// r4 = l0×l4 + l1×l3 + l2×l2 + l3×l1 + l4×l0 = 2×l0×l4 + 2×l1×l3 + l2×l2
-	r4 := mul64(l0_2, l4)
-	r4 = addMul64(r4, l1_2, l3)
-	r4 = addMul64(r4, l2, l2)
-
-	c0 := shiftRightBy51(r0)
-	c1 := shiftRightBy51(r1)
-	c2 := shiftRightBy51(r2)
-	c3 := shiftRightBy51(r3)
-	c4 := shiftRightBy51(r4)
-
-	rr0 := r0.lo&maskLow51Bits + c4*19
-	rr1 := r1.lo&maskLow51Bits + c0
-	rr2 := r2.lo&maskLow51Bits + c1
-	rr3 := r3.lo&maskLow51Bits + c2
-	rr4 := r4.lo&maskLow51Bits + c3
-
-	*v = Element{rr0, rr1, rr2, rr3, rr4}
-	v.carryPropagate()
-}
-
-// carryPropagate brings the limbs below 52 bits by applying the reduction
-// identity (a * 2²⁵⁵ + b = a * 19 + b) to the l4 carry.
-func (v *Element) carryPropagateGeneric() *Element {
-	c0 := v.l0 >> 51
-	c1 := v.l1 >> 51
-	c2 := v.l2 >> 51
-	c3 := v.l3 >> 51
-	c4 := v.l4 >> 51
-
-	v.l0 = v.l0&maskLow51Bits + c4*19
-	v.l1 = v.l1&maskLow51Bits + c0
-	v.l2 = v.l2&maskLow51Bits + c1
-	v.l3 = v.l3&maskLow51Bits + c2
-	v.l4 = v.l4&maskLow51Bits + c3
-
-	return v
-}
diff --git a/contrib/go/_std_1.18/src/crypto/ed25519/internal/edwards25519/scalar.go b/contrib/go/_std_1.18/src/crypto/ed25519/internal/edwards25519/scalar.go
deleted file mode 100644
index 889acaa0f1..0000000000
--- a/contrib/go/_std_1.18/src/crypto/ed25519/internal/edwards25519/scalar.go
+++ /dev/null
@@ -1,1025 +0,0 @@
-// Copyright (c) 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package edwards25519
-
-import (
-	"crypto/subtle"
-	"encoding/binary"
-	"errors"
-)
-
-// A Scalar is an integer modulo
-//
-//     l = 2^252 + 27742317777372353535851937790883648493
-//
-// which is the prime order of the edwards25519 group.
-//
-// This type works similarly to math/big.Int, and all arguments and
-// receivers are allowed to alias.
-//
-// The zero value is a valid zero element.
-type Scalar struct {
-	// s is the Scalar value in little-endian. The value is always reduced
-	// between operations.
-	s [32]byte
-}
-
-var (
-	scZero = Scalar{[32]byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}}
-
-	scOne = Scalar{[32]byte{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}}
-
-	scMinusOne = Scalar{[32]byte{236, 211, 245, 92, 26, 99, 18, 88, 214, 156, 247, 162, 222, 249, 222, 20, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 16}}
-)
-
-// NewScalar returns a new zero Scalar.
-func NewScalar() *Scalar {
-	return &Scalar{}
-}
-
-// MultiplyAdd sets s = x * y + z mod l, and returns s.
-func (s *Scalar) MultiplyAdd(x, y, z *Scalar) *Scalar {
-	scMulAdd(&s.s, &x.s, &y.s, &z.s)
-	return s
-}
-
-// Add sets s = x + y mod l, and returns s.
-func (s *Scalar) Add(x, y *Scalar) *Scalar {
-	// s = 1 * x + y mod l
-	scMulAdd(&s.s, &scOne.s, &x.s, &y.s)
-	return s
-}
-
-// Subtract sets s = x - y mod l, and returns s.
-func (s *Scalar) Subtract(x, y *Scalar) *Scalar {
-	// s = -1 * y + x mod l
-	scMulAdd(&s.s, &scMinusOne.s, &y.s, &x.s)
-	return s
-}
-
-// Negate sets s = -x mod l, and returns s.
-func (s *Scalar) Negate(x *Scalar) *Scalar {
-	// s = -1 * x + 0 mod l
-	scMulAdd(&s.s, &scMinusOne.s, &x.s, &scZero.s)
-	return s
-}
-
-// Multiply sets s = x * y mod l, and returns s.
-func (s *Scalar) Multiply(x, y *Scalar) *Scalar {
-	// s = x * y + 0 mod l
-	scMulAdd(&s.s, &x.s, &y.s, &scZero.s)
-	return s
-}
-
-// Set sets s = x, and returns s.
-func (s *Scalar) Set(x *Scalar) *Scalar {
-	*s = *x
-	return s
-}
-
-// SetUniformBytes sets s to an uniformly distributed value given 64 uniformly
-// distributed random bytes.
-func (s *Scalar) SetUniformBytes(x []byte) *Scalar {
-	if len(x) != 64 {
-		panic("edwards25519: invalid SetUniformBytes input length")
-	}
-	var wideBytes [64]byte
-	copy(wideBytes[:], x[:])
-	scReduce(&s.s, &wideBytes)
-	return s
-}
-
-// SetCanonicalBytes sets s = x, where x is a 32-byte little-endian encoding of
-// s, and returns s. If x is not a canonical encoding of s, SetCanonicalBytes
-// returns nil and an error, and the receiver is unchanged.
-func (s *Scalar) SetCanonicalBytes(x []byte) (*Scalar, error) {
-	if len(x) != 32 {
-		return nil, errors.New("invalid scalar length")
-	}
-	ss := &Scalar{}
-	copy(ss.s[:], x)
-	if !isReduced(ss) {
-		return nil, errors.New("invalid scalar encoding")
-	}
-	s.s = ss.s
-	return s, nil
-}
-
-// isReduced returns whether the given scalar is reduced modulo l.
-func isReduced(s *Scalar) bool {
-	for i := len(s.s) - 1; i >= 0; i-- {
-		switch {
-		case s.s[i] > scMinusOne.s[i]:
-			return false
-		case s.s[i] < scMinusOne.s[i]:
-			return true
-		}
-	}
-	return true
-}
-
-// SetBytesWithClamping applies the buffer pruning described in RFC 8032,
-// Section 5.1.5 (also known as clamping) and sets s to the result. The input
-// must be 32 bytes, and it is not modified.
-//
-// Note that since Scalar values are always reduced modulo the prime order of
-// the curve, the resulting value will not preserve any of the cofactor-clearing
-// properties that clamping is meant to provide. It will however work as
-// expected as long as it is applied to points on the prime order subgroup, like
-// in Ed25519. In fact, it is lost to history why RFC 8032 adopted the
-// irrelevant RFC 7748 clamping, but it is now required for compatibility.
-func (s *Scalar) SetBytesWithClamping(x []byte) *Scalar {
-	// The description above omits the purpose of the high bits of the clamping
-	// for brevity, but those are also lost to reductions, and are also
-	// irrelevant to edwards25519 as they protect against a specific
-	// implementation bug that was once observed in a generic Montgomery ladder.
-	if len(x) != 32 {
-		panic("edwards25519: invalid SetBytesWithClamping input length")
-	}
-	var wideBytes [64]byte
-	copy(wideBytes[:], x[:])
-	wideBytes[0] &= 248
-	wideBytes[31] &= 63
-	wideBytes[31] |= 64
-	scReduce(&s.s, &wideBytes)
-	return s
-}
-
-// Bytes returns the canonical 32-byte little-endian encoding of s.
-func (s *Scalar) Bytes() []byte {
-	buf := make([]byte, 32)
-	copy(buf, s.s[:])
-	return buf
-}
-
-// Equal returns 1 if s and t are equal, and 0 otherwise.
-func (s *Scalar) Equal(t *Scalar) int {
-	return subtle.ConstantTimeCompare(s.s[:], t.s[:])
-}
-
-// scMulAdd and scReduce are ported from the public domain, “ref10”
-// implementation of ed25519 from SUPERCOP.
-
-func load3(in []byte) int64 {
-	r := int64(in[0])
-	r |= int64(in[1]) << 8
-	r |= int64(in[2]) << 16
-	return r
-}
-
-func load4(in []byte) int64 {
-	r := int64(in[0])
-	r |= int64(in[1]) << 8
-	r |= int64(in[2]) << 16
-	r |= int64(in[3]) << 24
-	return r
-}
-
-// Input:
-//   a[0]+256*a[1]+...+256^31*a[31] = a
-//   b[0]+256*b[1]+...+256^31*b[31] = b
-//   c[0]+256*c[1]+...+256^31*c[31] = c
-//
-// Output:
-//   s[0]+256*s[1]+...+256^31*s[31] = (ab+c) mod l
-//   where l = 2^252 + 27742317777372353535851937790883648493.
-func scMulAdd(s, a, b, c *[32]byte) {
-	a0 := 2097151 & load3(a[:])
-	a1 := 2097151 & (load4(a[2:]) >> 5)
-	a2 := 2097151 & (load3(a[5:]) >> 2)
-	a3 := 2097151 & (load4(a[7:]) >> 7)
-	a4 := 2097151 & (load4(a[10:]) >> 4)
-	a5 := 2097151 & (load3(a[13:]) >> 1)
-	a6 := 2097151 & (load4(a[15:]) >> 6)
-	a7 := 2097151 & (load3(a[18:]) >> 3)
-	a8 := 2097151 & load3(a[21:])
-	a9 := 2097151 & (load4(a[23:]) >> 5)
-	a10 := 2097151 & (load3(a[26:]) >> 2)
-	a11 := (load4(a[28:]) >> 7)
-	b0 := 2097151 & load3(b[:])
-	b1 := 2097151 & (load4(b[2:]) >> 5)
-	b2 := 2097151 & (load3(b[5:]) >> 2)
-	b3 := 2097151 & (load4(b[7:]) >> 7)
-	b4 := 2097151 & (load4(b[10:]) >> 4)
-	b5 := 2097151 & (load3(b[13:]) >> 1)
-	b6 := 2097151 & (load4(b[15:]) >> 6)
-	b7 := 2097151 & (load3(b[18:]) >> 3)
-	b8 := 2097151 & load3(b[21:])
-	b9 := 2097151 & (load4(b[23:]) >> 5)
-	b10 := 2097151 & (load3(b[26:]) >> 2)
-	b11 := (load4(b[28:]) >> 7)
-	c0 := 2097151 & load3(c[:])
-	c1 := 2097151 & (load4(c[2:]) >> 5)
-	c2 := 2097151 & (load3(c[5:]) >> 2)
-	c3 := 2097151 & (load4(c[7:]) >> 7)
-	c4 := 2097151 & (load4(c[10:]) >> 4)
-	c5 := 2097151 & (load3(c[13:]) >> 1)
-	c6 := 2097151 & (load4(c[15:]) >> 6)
-	c7 := 2097151 & (load3(c[18:]) >> 3)
-	c8 := 2097151 & load3(c[21:])
-	c9 := 2097151 & (load4(c[23:]) >> 5)
-	c10 := 2097151 & (load3(c[26:]) >> 2)
-	c11 := (load4(c[28:]) >> 7)
-	var carry [23]int64
-
-	s0 := c0 + a0*b0
-	s1 := c1 + a0*b1 + a1*b0
-	s2 := c2 + a0*b2 + a1*b1 + a2*b0
-	s3 := c3 + a0*b3 + a1*b2 + a2*b1 + a3*b0
-	s4 := c4 + a0*b4 + a1*b3 + a2*b2 + a3*b1 + a4*b0
-	s5 := c5 + a0*b5 + a1*b4 + a2*b3 + a3*b2 + a4*b1 + a5*b0
-	s6 := c6 + a0*b6 + a1*b5 + a2*b4 + a3*b3 + a4*b2 + a5*b1 + a6*b0
-	s7 := c7 + a0*b7 + a1*b6 + a2*b5 + a3*b4 + a4*b3 + a5*b2 + a6*b1 + a7*b0
-	s8 := c8 + a0*b8 + a1*b7 + a2*b6 + a3*b5 + a4*b4 + a5*b3 + a6*b2 + a7*b1 + a8*b0
-	s9 := c9 + a0*b9 + a1*b8 + a2*b7 + a3*b6 + a4*b5 + a5*b4 + a6*b3 + a7*b2 + a8*b1 + a9*b0
-	s10 := c10 + a0*b10 + a1*b9 + a2*b8 + a3*b7 + a4*b6 + a5*b5 + a6*b4 + a7*b3 + a8*b2 + a9*b1 + a10*b0
-	s11 := c11 + a0*b11 + a1*b10 + a2*b9 + a3*b8 + a4*b7 + a5*b6 + a6*b5 + a7*b4 + a8*b3 + a9*b2 + a10*b1 + a11*b0
-	s12 := a1*b11 + a2*b10 + a3*b9 + a4*b8 + a5*b7 + a6*b6 + a7*b5 + a8*b4 + a9*b3 + a10*b2 + a11*b1
-	s13 := a2*b11 + a3*b10 + a4*b9 + a5*b8 + a6*b7 + a7*b6 + a8*b5 + a9*b4 + a10*b3 + a11*b2
-	s14 := a3*b11 + a4*b10 + a5*b9 + a6*b8 + a7*b7 + a8*b6 + a9*b5 + a10*b4 + a11*b3
-	s15 := a4*b11 + a5*b10 + a6*b9 + a7*b8 + a8*b7 + a9*b6 + a10*b5 + a11*b4
-	s16 := a5*b11 + a6*b10 + a7*b9 + a8*b8 + a9*b7 + a10*b6 + a11*b5
-	s17 := a6*b11 + a7*b10 + a8*b9 + a9*b8 + a10*b7 + a11*b6
-	s18 := a7*b11 + a8*b10 + a9*b9 + a10*b8 + a11*b7
-	s19 := a8*b11 + a9*b10 + a10*b9 + a11*b8
-	s20 := a9*b11 + a10*b10 + a11*b9
-	s21 := a10*b11 + a11*b10
-	s22 := a11 * b11
-	s23 := int64(0)
-
-	carry[0] = (s0 + (1 << 20)) >> 21
-	s1 += carry[0]
-	s0 -= carry[0] << 21
-	carry[2] = (s2 + (1 << 20)) >> 21
-	s3 += carry[2]
-	s2 -= carry[2] << 21
-	carry[4] = (s4 + (1 << 20)) >> 21
-	s5 += carry[4]
-	s4 -= carry[4] << 21
-	carry[6] = (s6 + (1 << 20)) >> 21
-	s7 += carry[6]
-	s6 -= carry[6] << 21
-	carry[8] = (s8 + (1 << 20)) >> 21
-	s9 += carry[8]
-	s8 -= carry[8] << 21
-	carry[10] = (s10 + (1 << 20)) >> 21
-	s11 += carry[10]
-	s10 -= carry[10] << 21
-	carry[12] = (s12 + (1 << 20)) >> 21
-	s13 += carry[12]
-	s12 -= carry[12] << 21
-	carry[14] = (s14 + (1 << 20)) >> 21
-	s15 += carry[14]
-	s14 -= carry[14] << 21
-	carry[16] = (s16 + (1 << 20)) >> 21
-	s17 += carry[16]
-	s16 -= carry[16] << 21
-	carry[18] = (s18 + (1 << 20)) >> 21
-	s19 += carry[18]
-	s18 -= carry[18] << 21
-	carry[20] = (s20 + (1 << 20)) >> 21
-	s21 += carry[20]
-	s20 -= carry[20] << 21
-	carry[22] = (s22 + (1 << 20)) >> 21
-	s23 += carry[22]
-	s22 -= carry[22] << 21
-
-	carry[1] = (s1 + (1 << 20)) >> 21
-	s2 += carry[1]
-	s1 -= carry[1] << 21
-	carry[3] = (s3 + (1 << 20)) >> 21
-	s4 += carry[3]
-	s3 -= carry[3] << 21
-	carry[5] = (s5 + (1 << 20)) >> 21
-	s6 += carry[5]
-	s5 -= carry[5] << 21
-	carry[7] = (s7 + (1 << 20)) >> 21
-	s8 += carry[7]
-	s7 -= carry[7] << 21
-	carry[9] = (s9 + (1 << 20)) >> 21
-	s10 += carry[9]
-	s9 -= carry[9] << 21
-	carry[11] = (s11 + (1 << 20)) >> 21
-	s12 += carry[11]
-	s11 -= carry[11] << 21
-	carry[13] = (s13 + (1 << 20)) >> 21
-	s14 += carry[13]
-	s13 -= carry[13] << 21
-	carry[15] = (s15 + (1 << 20)) >> 21
-	s16 += carry[15]
-	s15 -= carry[15] << 21
-	carry[17] = (s17 + (1 << 20)) >> 21
-	s18 += carry[17]
-	s17 -= carry[17] << 21
-	carry[19] = (s19 + (1 << 20)) >> 21
-	s20 += carry[19]
-	s19 -= carry[19] << 21
-	carry[21] = (s21 + (1 << 20)) >> 21
-	s22 += carry[21]
-	s21 -= carry[21] << 21
-
-	s11 += s23 * 666643
-	s12 += s23 * 470296
-	s13 += s23 * 654183
-	s14 -= s23 * 997805
-	s15 += s23 * 136657
-	s16 -= s23 * 683901
-	s23 = 0
-
-	s10 += s22 * 666643
-	s11 += s22 * 470296
-	s12 += s22 * 654183
-	s13 -= s22 * 997805
-	s14 += s22 * 136657
-	s15 -= s22 * 683901
-	s22 = 0
-
-	s9 += s21 * 666643
-	s10 += s21 * 470296
-	s11 += s21 * 654183
-	s12 -= s21 * 997805
-	s13 += s21 * 136657
-	s14 -= s21 * 683901
-	s21 = 0
-
-	s8 += s20 * 666643
-	s9 += s20 * 470296
-	s10 += s20 * 654183
-	s11 -= s20 * 997805
-	s12 += s20 * 136657
-	s13 -= s20 * 683901
-	s20 = 0
-
-	s7 += s19 * 666643
-	s8 += s19 * 470296
-	s9 += s19 * 654183
-	s10 -= s19 * 997805
-	s11 += s19 * 136657
-	s12 -= s19 * 683901
-	s19 = 0
-
-	s6 += s18 * 666643
-	s7 += s18 * 470296
-	s8 += s18 * 654183
-	s9 -= s18 * 997805
-	s10 += s18 * 136657
-	s11 -= s18 * 683901
-	s18 = 0
-
-	carry[6] = (s6 + (1 << 20)) >> 21
-	s7 += carry[6]
-	s6 -= carry[6] << 21
-	carry[8] = (s8 + (1 << 20)) >> 21
-	s9 += carry[8]
-	s8 -= carry[8] << 21
-	carry[10] = (s10 + (1 << 20)) >> 21
-	s11 += carry[10]
-	s10 -= carry[10] << 21
-	carry[12] = (s12 + (1 << 20)) >> 21
-	s13 += carry[12]
-	s12 -= carry[12] << 21
-	carry[14] = (s14 + (1 << 20)) >> 21
-	s15 += carry[14]
-	s14 -= carry[14] << 21
-	carry[16] = (s16 + (1 << 20)) >> 21
-	s17 += carry[16]
-	s16 -= carry[16] << 21
-
-	carry[7] = (s7 + (1 << 20)) >> 21
-	s8 += carry[7]
-	s7 -= carry[7] << 21
-	carry[9] = (s9 + (1 << 20)) >> 21
-	s10 += carry[9]
-	s9 -= carry[9] << 21
-	carry[11] = (s11 + (1 << 20)) >> 21
-	s12 += carry[11]
-	s11 -= carry[11] << 21
-	carry[13] = (s13 + (1 << 20)) >> 21
-	s14 += carry[13]
-	s13 -= carry[13] << 21
-	carry[15] = (s15 + (1 << 20)) >> 21
-	s16 += carry[15]
-	s15 -= carry[15] << 21
-
-	s5 += s17 * 666643
-	s6 += s17 * 470296
-	s7 += s17 * 654183
-	s8 -= s17 * 997805
-	s9 += s17 * 136657
-	s10 -= s17 * 683901
-	s17 = 0
-
-	s4 += s16 * 666643
-	s5 += s16 * 470296
-	s6 += s16 * 654183
-	s7 -= s16 * 997805
-	s8 += s16 * 136657
-	s9 -= s16 * 683901
-	s16 = 0
-
-	s3 += s15 * 666643
-	s4 += s15 * 470296
-	s5 += s15 * 654183
-	s6 -= s15 * 997805
-	s7 += s15 * 136657
-	s8 -= s15 * 683901
-	s15 = 0
-
-	s2 += s14 * 666643
-	s3 += s14 * 470296
-	s4 += s14 * 654183
-	s5 -= s14 * 997805
-	s6 += s14 * 136657
-	s7 -= s14 * 683901
-	s14 = 0
-
-	s1 += s13 * 666643
-	s2 += s13 * 470296
-	s3 += s13 * 654183
-	s4 -= s13 * 997805
-	s5 += s13 * 136657
-	s6 -= s13 * 683901
-	s13 = 0
-
-	s0 += s12 * 666643
-	s1 += s12 * 470296
-	s2 += s12 * 654183
-	s3 -= s12 * 997805
-	s4 += s12 * 136657
-	s5 -= s12 * 683901
-	s12 = 0
-
-	carry[0] = (s0 + (1 << 20)) >> 21
-	s1 += carry[0]
-	s0 -= carry[0] << 21
-	carry[2] = (s2 + (1 << 20)) >> 21
-	s3 += carry[2]
-	s2 -= carry[2] << 21
-	carry[4] = (s4 + (1 << 20)) >> 21
-	s5 += carry[4]
-	s4 -= carry[4] << 21
-	carry[6] = (s6 + (1 << 20)) >> 21
-	s7 += carry[6]
-	s6 -= carry[6] << 21
-	carry[8] = (s8 + (1 << 20)) >> 21
-	s9 += carry[8]
-	s8 -= carry[8] << 21
-	carry[10] = (s10 + (1 << 20)) >> 21
-	s11 += carry[10]
-	s10 -= carry[10] << 21
-
-	carry[1] = (s1 + (1 << 20)) >> 21
-	s2 += carry[1]
-	s1 -= carry[1] << 21
-	carry[3] = (s3 + (1 << 20)) >> 21
-	s4 += carry[3]
-	s3 -= carry[3] << 21
-	carry[5] = (s5 + (1 << 20)) >> 21
-	s6 += carry[5]
-	s5 -= carry[5] << 21
-	carry[7] = (s7 + (1 << 20)) >> 21
-	s8 += carry[7]
-	s7 -= carry[7] << 21
-	carry[9] = (s9 + (1 << 20)) >> 21
-	s10 += carry[9]
-	s9 -= carry[9] << 21
-	carry[11] = (s11 + (1 << 20)) >> 21
-	s12 += carry[11]
-	s11 -= carry[11] << 21
-
-	s0 += s12 * 666643
-	s1 += s12 * 470296
-	s2 += s12 * 654183
-	s3 -= s12 * 997805
-	s4 += s12 * 136657
-	s5 -= s12 * 683901
-	s12 = 0
-
-	carry[0] = s0 >> 21
-	s1 += carry[0]
-	s0 -= carry[0] << 21
-	carry[1] = s1 >> 21
-	s2 += carry[1]
-	s1 -= carry[1] << 21
-	carry[2] = s2 >> 21
-	s3 += carry[2]
-	s2 -= carry[2] << 21
-	carry[3] = s3 >> 21
-	s4 += carry[3]
-	s3 -= carry[3] << 21
-	carry[4] = s4 >> 21
-	s5 += carry[4]
-	s4 -= carry[4] << 21
-	carry[5] = s5 >> 21
-	s6 += carry[5]
-	s5 -= carry[5] << 21
-	carry[6] = s6 >> 21
-	s7 += carry[6]
-	s6 -= carry[6] << 21
-	carry[7] = s7 >> 21
-	s8 += carry[7]
-	s7 -= carry[7] << 21
-	carry[8] = s8 >> 21
-	s9 += carry[8]
-	s8 -= carry[8] << 21
-	carry[9] = s9 >> 21
-	s10 += carry[9]
-	s9 -= carry[9] << 21
-	carry[10] = s10 >> 21
-	s11 += carry[10]
-	s10 -= carry[10] << 21
-	carry[11] = s11 >> 21
-	s12 += carry[11]
-	s11 -= carry[11] << 21
-
-	s0 += s12 * 666643
-	s1 += s12 * 470296
-	s2 += s12 * 654183
-	s3 -= s12 * 997805
-	s4 += s12 * 136657
-	s5 -= s12 * 683901
-	s12 = 0
-
-	carry[0] = s0 >> 21
-	s1 += carry[0]
-	s0 -= carry[0] << 21
-	carry[1] = s1 >> 21
-	s2 += carry[1]
-	s1 -= carry[1] << 21
-	carry[2] = s2 >> 21
-	s3 += carry[2]
-	s2 -= carry[2] << 21
-	carry[3] = s3 >> 21
-	s4 += carry[3]
-	s3 -= carry[3] << 21
-	carry[4] = s4 >> 21
-	s5 += carry[4]
-	s4 -= carry[4] << 21
-	carry[5] = s5 >> 21
-	s6 += carry[5]
-	s5 -= carry[5] << 21
-	carry[6] = s6 >> 21
-	s7 += carry[6]
-	s6 -= carry[6] << 21
-	carry[7] = s7 >> 21
-	s8 += carry[7]
-	s7 -= carry[7] << 21
-	carry[8] = s8 >> 21
-	s9 += carry[8]
-	s8 -= carry[8] << 21
-	carry[9] = s9 >> 21
-	s10 += carry[9]
-	s9 -= carry[9] << 21
-	carry[10] = s10 >> 21
-	s11 += carry[10]
-	s10 -= carry[10] << 21
-
-	s[0] = byte(s0 >> 0)
-	s[1] = byte(s0 >> 8)
-	s[2] = byte((s0 >> 16) | (s1 << 5))
-	s[3] = byte(s1 >> 3)
-	s[4] = byte(s1 >> 11)
-	s[5] = byte((s1 >> 19) | (s2 << 2))
-	s[6] = byte(s2 >> 6)
-	s[7] = byte((s2 >> 14) | (s3 << 7))
-	s[8] = byte(s3 >> 1)
-	s[9] = byte(s3 >> 9)
-	s[10] = byte((s3 >> 17) | (s4 << 4))
-	s[11] = byte(s4 >> 4)
-	s[12] = byte(s4 >> 12)
-	s[13] = byte((s4 >> 20) | (s5 << 1))
-	s[14] = byte(s5 >> 7)
-	s[15] = byte((s5 >> 15) | (s6 << 6))
-	s[16] = byte(s6 >> 2)
-	s[17] = byte(s6 >> 10)
-	s[18] = byte((s6 >> 18) | (s7 << 3))
-	s[19] = byte(s7 >> 5)
-	s[20] = byte(s7 >> 13)
-	s[21] = byte(s8 >> 0)
-	s[22] = byte(s8 >> 8)
-	s[23] = byte((s8 >> 16) | (s9 << 5))
-	s[24] = byte(s9 >> 3)
-	s[25] = byte(s9 >> 11)
-	s[26] = byte((s9 >> 19) | (s10 << 2))
-	s[27] = byte(s10 >> 6)
-	s[28] = byte((s10 >> 14) | (s11 << 7))
-	s[29] = byte(s11 >> 1)
-	s[30] = byte(s11 >> 9)
-	s[31] = byte(s11 >> 17)
-}
-
-// Input:
-//   s[0]+256*s[1]+...+256^63*s[63] = s
-//
-// Output:
-//   s[0]+256*s[1]+...+256^31*s[31] = s mod l
-//   where l = 2^252 + 27742317777372353535851937790883648493.
-func scReduce(out *[32]byte, s *[64]byte) {
-	s0 := 2097151 & load3(s[:])
-	s1 := 2097151 & (load4(s[2:]) >> 5)
-	s2 := 2097151 & (load3(s[5:]) >> 2)
-	s3 := 2097151 & (load4(s[7:]) >> 7)
-	s4 := 2097151 & (load4(s[10:]) >> 4)
-	s5 := 2097151 & (load3(s[13:]) >> 1)
-	s6 := 2097151 & (load4(s[15:]) >> 6)
-	s7 := 2097151 & (load3(s[18:]) >> 3)
-	s8 := 2097151 & load3(s[21:])
-	s9 := 2097151 & (load4(s[23:]) >> 5)
-	s10 := 2097151 & (load3(s[26:]) >> 2)
-	s11 := 2097151 & (load4(s[28:]) >> 7)
-	s12 := 2097151 & (load4(s[31:]) >> 4)
-	s13 := 2097151 & (load3(s[34:]) >> 1)
-	s14 := 2097151 & (load4(s[36:]) >> 6)
-	s15 := 2097151 & (load3(s[39:]) >> 3)
-	s16 := 2097151 & load3(s[42:])
-	s17 := 2097151 & (load4(s[44:]) >> 5)
-	s18 := 2097151 & (load3(s[47:]) >> 2)
-	s19 := 2097151 & (load4(s[49:]) >> 7)
-	s20 := 2097151 & (load4(s[52:]) >> 4)
-	s21 := 2097151 & (load3(s[55:]) >> 1)
-	s22 := 2097151 & (load4(s[57:]) >> 6)
-	s23 := (load4(s[60:]) >> 3)
-
-	s11 += s23 * 666643
-	s12 += s23 * 470296
-	s13 += s23 * 654183
-	s14 -= s23 * 997805
-	s15 += s23 * 136657
-	s16 -= s23 * 683901
-	s23 = 0
-
-	s10 += s22 * 666643
-	s11 += s22 * 470296
-	s12 += s22 * 654183
-	s13 -= s22 * 997805
-	s14 += s22 * 136657
-	s15 -= s22 * 683901
-	s22 = 0
-
-	s9 += s21 * 666643
-	s10 += s21 * 470296
-	s11 += s21 * 654183
-	s12 -= s21 * 997805
-	s13 += s21 * 136657
-	s14 -= s21 * 683901
-	s21 = 0
-
-	s8 += s20 * 666643
-	s9 += s20 * 470296
-	s10 += s20 * 654183
-	s11 -= s20 * 997805
-	s12 += s20 * 136657
-	s13 -= s20 * 683901
-	s20 = 0
-
-	s7 += s19 * 666643
-	s8 += s19 * 470296
-	s9 += s19 * 654183
-	s10 -= s19 * 997805
-	s11 += s19 * 136657
-	s12 -= s19 * 683901
-	s19 = 0
-
-	s6 += s18 * 666643
-	s7 += s18 * 470296
-	s8 += s18 * 654183
-	s9 -= s18 * 997805
-	s10 += s18 * 136657
-	s11 -= s18 * 683901
-	s18 = 0
-
-	var carry [17]int64
-
-	carry[6] = (s6 + (1 << 20)) >> 21
-	s7 += carry[6]
-	s6 -= carry[6] << 21
-	carry[8] = (s8 + (1 << 20)) >> 21
-	s9 += carry[8]
-	s8 -= carry[8] << 21
-	carry[10] = (s10 + (1 << 20)) >> 21
-	s11 += carry[10]
-	s10 -= carry[10] << 21
-	carry[12] = (s12 + (1 << 20)) >> 21
-	s13 += carry[12]
-	s12 -= carry[12] << 21
-	carry[14] = (s14 + (1 << 20)) >> 21
-	s15 += carry[14]
-	s14 -= carry[14] << 21
-	carry[16] = (s16 + (1 << 20)) >> 21
-	s17 += carry[16]
-	s16 -= carry[16] << 21
-
-	carry[7] = (s7 + (1 << 20)) >> 21
-	s8 += carry[7]
-	s7 -= carry[7] << 21
-	carry[9] = (s9 + (1 << 20)) >> 21
-	s10 += carry[9]
-	s9 -= carry[9] << 21
-	carry[11] = (s11 + (1 << 20)) >> 21
-	s12 += carry[11]
-	s11 -= carry[11] << 21
-	carry[13] = (s13 + (1 << 20)) >> 21
-	s14 += carry[13]
-	s13 -= carry[13] << 21
-	carry[15] = (s15 + (1 << 20)) >> 21
-	s16 += carry[15]
-	s15 -= carry[15] << 21
-
-	s5 += s17 * 666643
-	s6 += s17 * 470296
-	s7 += s17 * 654183
-	s8 -= s17 * 997805
-	s9 += s17 * 136657
-	s10 -= s17 * 683901
-	s17 = 0
-
-	s4 += s16 * 666643
-	s5 += s16 * 470296
-	s6 += s16 * 654183
-	s7 -= s16 * 997805
-	s8 += s16 * 136657
-	s9 -= s16 * 683901
-	s16 = 0
-
-	s3 += s15 * 666643
-	s4 += s15 * 470296
-	s5 += s15 * 654183
-	s6 -= s15 * 997805
-	s7 += s15 * 136657
-	s8 -= s15 * 683901
-	s15 = 0
-
-	s2 += s14 * 666643
-	s3 += s14 * 470296
-	s4 += s14 * 654183
-	s5 -= s14 * 997805
-	s6 += s14 * 136657
-	s7 -= s14 * 683901
-	s14 = 0
-
-	s1 += s13 * 666643
-	s2 += s13 * 470296
-	s3 += s13 * 654183
-	s4 -= s13 * 997805
-	s5 += s13 * 136657
-	s6 -= s13 * 683901
-	s13 = 0
-
-	s0 += s12 * 666643
-	s1 += s12 * 470296
-	s2 += s12 * 654183
-	s3 -= s12 * 997805
-	s4 += s12 * 136657
-	s5 -= s12 * 683901
-	s12 = 0
-
-	carry[0] = (s0 + (1 << 20)) >> 21
-	s1 += carry[0]
-	s0 -= carry[0] << 21
-	carry[2] = (s2 + (1 << 20)) >> 21
-	s3 += carry[2]
-	s2 -= carry[2] << 21
-	carry[4] = (s4 + (1 << 20)) >> 21
-	s5 += carry[4]
-	s4 -= carry[4] << 21
-	carry[6] = (s6 + (1 << 20)) >> 21
-	s7 += carry[6]
-	s6 -= carry[6] << 21
-	carry[8] = (s8 + (1 << 20)) >> 21
-	s9 += carry[8]
-	s8 -= carry[8] << 21
-	carry[10] = (s10 + (1 << 20)) >> 21
-	s11 += carry[10]
-	s10 -= carry[10] << 21
-
-	carry[1] = (s1 + (1 << 20)) >> 21
-	s2 += carry[1]
-	s1 -= carry[1] << 21
-	carry[3] = (s3 + (1 << 20)) >> 21
-	s4 += carry[3]
-	s3 -= carry[3] << 21
-	carry[5] = (s5 + (1 << 20)) >> 21
-	s6 += carry[5]
-	s5 -= carry[5] << 21
-	carry[7] = (s7 + (1 << 20)) >> 21
-	s8 += carry[7]
-	s7 -= carry[7] << 21
-	carry[9] = (s9 + (1 << 20)) >> 21
-	s10 += carry[9]
-	s9 -= carry[9] << 21
-	carry[11] = (s11 + (1 << 20)) >> 21
-	s12 += carry[11]
-	s11 -= carry[11] << 21
-
-	s0 += s12 * 666643
-	s1 += s12 * 470296
-	s2 += s12 * 654183
-	s3 -= s12 * 997805
-	s4 += s12 * 136657
-	s5 -= s12 * 683901
-	s12 = 0
-
-	carry[0] = s0 >> 21
-	s1 += carry[0]
-	s0 -= carry[0] << 21
-	carry[1] = s1 >> 21
-	s2 += carry[1]
-	s1 -= carry[1] << 21
-	carry[2] = s2 >> 21
-	s3 += carry[2]
-	s2 -= carry[2] << 21
-	carry[3] = s3 >> 21
-	s4 += carry[3]
-	s3 -= carry[3] << 21
-	carry[4] = s4 >> 21
-	s5 += carry[4]
-	s4 -= carry[4] << 21
-	carry[5] = s5 >> 21
-	s6 += carry[5]
-	s5 -= carry[5] << 21
-	carry[6] = s6 >> 21
-	s7 += carry[6]
-	s6 -= carry[6] << 21
-	carry[7] = s7 >> 21
-	s8 += carry[7]
-	s7 -= carry[7] << 21
-	carry[8] = s8 >> 21
-	s9 += carry[8]
-	s8 -= carry[8] << 21
-	carry[9] = s9 >> 21
-	s10 += carry[9]
-	s9 -= carry[9] << 21
-	carry[10] = s10 >> 21
-	s11 += carry[10]
-	s10 -= carry[10] << 21
-	carry[11] = s11 >> 21
-	s12 += carry[11]
-	s11 -= carry[11] << 21
-
-	s0 += s12 * 666643
-	s1 += s12 * 470296
-	s2 += s12 * 654183
-	s3 -= s12 * 997805
-	s4 += s12 * 136657
-	s5 -= s12 * 683901
-	s12 = 0
-
-	carry[0] = s0 >> 21
-	s1 += carry[0]
-	s0 -= carry[0] << 21
-	carry[1] = s1 >> 21
-	s2 += carry[1]
-	s1 -= carry[1] << 21
-	carry[2] = s2 >> 21
-	s3 += carry[2]
-	s2 -= carry[2] << 21
-	carry[3] = s3 >> 21
-	s4 += carry[3]
-	s3 -= carry[3] << 21
-	carry[4] = s4 >> 21
-	s5 += carry[4]
-	s4 -= carry[4] << 21
-	carry[5] = s5 >> 21
-	s6 += carry[5]
-	s5 -= carry[5] << 21
-	carry[6] = s6 >> 21
-	s7 += carry[6]
-	s6 -= carry[6] << 21
-	carry[7] = s7 >> 21
-	s8 += carry[7]
-	s7 -= carry[7] << 21
-	carry[8] = s8 >> 21
-	s9 += carry[8]
-	s8 -= carry[8] << 21
-	carry[9] = s9 >> 21
-	s10 += carry[9]
-	s9 -= carry[9] << 21
-	carry[10] = s10 >> 21
-	s11 += carry[10]
-	s10 -= carry[10] << 21
-
-	out[0] = byte(s0 >> 0)
-	out[1] = byte(s0 >> 8)
-	out[2] = byte((s0 >> 16) | (s1 << 5))
-	out[3] = byte(s1 >> 3)
-	out[4] = byte(s1 >> 11)
-	out[5] = byte((s1 >> 19) | (s2 << 2))
-	out[6] = byte(s2 >> 6)
-	out[7] = byte((s2 >> 14) | (s3 << 7))
-	out[8] = byte(s3 >> 1)
-	out[9] = byte(s3 >> 9)
-	out[10] = byte((s3 >> 17) | (s4 << 4))
-	out[11] = byte(s4 >> 4)
-	out[12] = byte(s4 >> 12)
-	out[13] = byte((s4 >> 20) | (s5 << 1))
-	out[14] = byte(s5 >> 7)
-	out[15] = byte((s5 >> 15) | (s6 << 6))
-	out[16] = byte(s6 >> 2)
-	out[17] = byte(s6 >> 10)
-	out[18] = byte((s6 >> 18) | (s7 << 3))
-	out[19] = byte(s7 >> 5)
-	out[20] = byte(s7 >> 13)
-	out[21] = byte(s8 >> 0)
-	out[22] = byte(s8 >> 8)
-	out[23] = byte((s8 >> 16) | (s9 << 5))
-	out[24] = byte(s9 >> 3)
-	out[25] = byte(s9 >> 11)
-	out[26] = byte((s9 >> 19) | (s10 << 2))
-	out[27] = byte(s10 >> 6)
-	out[28] = byte((s10 >> 14) | (s11 << 7))
-	out[29] = byte(s11 >> 1)
-	out[30] = byte(s11 >> 9)
-	out[31] = byte(s11 >> 17)
-}
-
-// nonAdjacentForm computes a width-w non-adjacent form for this scalar.
-//
-// w must be between 2 and 8, or nonAdjacentForm will panic.
-func (s *Scalar) nonAdjacentForm(w uint) [256]int8 {
-	// This implementation is adapted from the one
-	// in curve25519-dalek and is documented there:
-	// https://github.com/dalek-cryptography/curve25519-dalek/blob/f630041af28e9a405255f98a8a93adca18e4315b/src/scalar.rs#L800-L871
-	if s.s[31] > 127 {
-		panic("scalar has high bit set illegally")
-	}
-	if w < 2 {
-		panic("w must be at least 2 by the definition of NAF")
-	} else if w > 8 {
-		panic("NAF digits must fit in int8")
-	}
-
-	var naf [256]int8
-	var digits [5]uint64
-
-	for i := 0; i < 4; i++ {
-		digits[i] = binary.LittleEndian.Uint64(s.s[i*8:])
-	}
-
-	width := uint64(1 << w)
-	windowMask := uint64(width - 1)
-
-	pos := uint(0)
-	carry := uint64(0)
-	for pos < 256 {
-		indexU64 := pos / 64
-		indexBit := pos % 64
-		var bitBuf uint64
-		if indexBit < 64-w {
-			// This window's bits are contained in a single u64
-			bitBuf = digits[indexU64] >> indexBit
-		} else {
-			// Combine the current 64 bits with bits from the next 64
-			bitBuf = (digits[indexU64] >> indexBit) | (digits[1+indexU64] << (64 - indexBit))
-		}
-
-		// Add carry into the current window
-		window := carry + (bitBuf & windowMask)
-
-		if window&1 == 0 {
-			// If the window value is even, preserve the carry and continue.
-			// Why is the carry preserved?
-			// If carry == 0 and window & 1 == 0,
-			//    then the next carry should be 0
-			// If carry == 1 and window & 1 == 0,
-			//    then bit_buf & 1 == 1 so the next carry should be 1
-			pos += 1
-			continue
-		}
-
-		if window < width/2 {
-			carry = 0
-			naf[pos] = int8(window)
-		} else {
-			carry = 1
-			naf[pos] = int8(window) - int8(width)
-		}
-
-		pos += w
-	}
-	return naf
-}
-
-func (s *Scalar) signedRadix16() [64]int8 {
-	if s.s[31] > 127 {
-		panic("scalar has high bit set illegally")
-	}
-
-	var digits [64]int8
-
-	// Compute unsigned radix-16 digits:
-	for i := 0; i < 32; i++ {
-		digits[2*i] = int8(s.s[i] & 15)
-		digits[2*i+1] = int8((s.s[i] >> 4) & 15)
-	}
-
-	// Recenter coefficients:
-	for i := 0; i < 63; i++ {
-		carry := (digits[i] + 8) >> 4
-		digits[i] -= carry << 4
-		digits[i+1] += carry
-	}
-
-	return digits
-}
diff --git a/contrib/go/_std_1.18/src/crypto/elliptic/elliptic.go b/contrib/go/_std_1.18/src/crypto/elliptic/elliptic.go
deleted file mode 100644
index 7ead09f8d3..0000000000
--- a/contrib/go/_std_1.18/src/crypto/elliptic/elliptic.go
+++ /dev/null
@@ -1,496 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package elliptic implements the standard NIST P-224, P-256, P-384, and P-521
-// elliptic curves over prime fields.
-package elliptic
-
-import (
-	"io"
-	"math/big"
-	"sync"
-)
-
-// A Curve represents a short-form Weierstrass curve with a=-3.
-//
-// The behavior of Add, Double, and ScalarMult when the input is not a point on
-// the curve is undefined.
-//
-// Note that the conventional point at infinity (0, 0) is not considered on the
-// curve, although it can be returned by Add, Double, ScalarMult, or
-// ScalarBaseMult (but not the Unmarshal or UnmarshalCompressed functions).
-type Curve interface {
-	// Params returns the parameters for the curve.
-	Params() *CurveParams
-	// IsOnCurve reports whether the given (x,y) lies on the curve.
-	IsOnCurve(x, y *big.Int) bool
-	// Add returns the sum of (x1,y1) and (x2,y2)
-	Add(x1, y1, x2, y2 *big.Int) (x, y *big.Int)
-	// Double returns 2*(x,y)
-	Double(x1, y1 *big.Int) (x, y *big.Int)
-	// ScalarMult returns k*(Bx,By) where k is a number in big-endian form.
-	ScalarMult(x1, y1 *big.Int, k []byte) (x, y *big.Int)
-	// ScalarBaseMult returns k*G, where G is the base point of the group
-	// and k is an integer in big-endian form.
-	ScalarBaseMult(k []byte) (x, y *big.Int)
-}
-
-func matchesSpecificCurve(params *CurveParams, available ...Curve) (Curve, bool) {
-	for _, c := range available {
-		if params == c.Params() {
-			return c, true
-		}
-	}
-	return nil, false
-}
-
-// CurveParams contains the parameters of an elliptic curve and also provides
-// a generic, non-constant time implementation of Curve.
-type CurveParams struct {
-	P       *big.Int // the order of the underlying field
-	N       *big.Int // the order of the base point
-	B       *big.Int // the constant of the curve equation
-	Gx, Gy  *big.Int // (x,y) of the base point
-	BitSize int      // the size of the underlying field
-	Name    string   // the canonical name of the curve
-}
-
-func (curve *CurveParams) Params() *CurveParams {
-	return curve
-}
-
-// CurveParams operates, internally, on Jacobian coordinates. For a given
-// (x, y) position on the curve, the Jacobian coordinates are (x1, y1, z1)
-// where x = x1/z1² and y = y1/z1³. The greatest speedups come when the whole
-// calculation can be performed within the transform (as in ScalarMult and
-// ScalarBaseMult). But even for Add and Double, it's faster to apply and
-// reverse the transform than to operate in affine coordinates.
-
-// polynomial returns x³ - 3x + b.
-func (curve *CurveParams) polynomial(x *big.Int) *big.Int {
-	x3 := new(big.Int).Mul(x, x)
-	x3.Mul(x3, x)
-
-	threeX := new(big.Int).Lsh(x, 1)
-	threeX.Add(threeX, x)
-
-	x3.Sub(x3, threeX)
-	x3.Add(x3, curve.B)
-	x3.Mod(x3, curve.P)
-
-	return x3
-}
-
-func (curve *CurveParams) IsOnCurve(x, y *big.Int) bool {
-	// If there is a dedicated constant-time implementation for this curve operation,
-	// use that instead of the generic one.
-	if specific, ok := matchesSpecificCurve(curve, p224, p384, p521); ok {
-		return specific.IsOnCurve(x, y)
-	}
-
-	if x.Sign() < 0 || x.Cmp(curve.P) >= 0 ||
-		y.Sign() < 0 || y.Cmp(curve.P) >= 0 {
-		return false
-	}
-
-	// y² = x³ - 3x + b
-	y2 := new(big.Int).Mul(y, y)
-	y2.Mod(y2, curve.P)
-
-	return curve.polynomial(x).Cmp(y2) == 0
-}
-
-// zForAffine returns a Jacobian Z value for the affine point (x, y). If x and
-// y are zero, it assumes that they represent the point at infinity because (0,
-// 0) is not on the any of the curves handled here.
-func zForAffine(x, y *big.Int) *big.Int {
-	z := new(big.Int)
-	if x.Sign() != 0 || y.Sign() != 0 {
-		z.SetInt64(1)
-	}
-	return z
-}
-
-// affineFromJacobian reverses the Jacobian transform. See the comment at the
-// top of the file. If the point is ∞ it returns 0, 0.
-func (curve *CurveParams) affineFromJacobian(x, y, z *big.Int) (xOut, yOut *big.Int) {
-	if z.Sign() == 0 {
-		return new(big.Int), new(big.Int)
-	}
-
-	zinv := new(big.Int).ModInverse(z, curve.P)
-	zinvsq := new(big.Int).Mul(zinv, zinv)
-
-	xOut = new(big.Int).Mul(x, zinvsq)
-	xOut.Mod(xOut, curve.P)
-	zinvsq.Mul(zinvsq, zinv)
-	yOut = new(big.Int).Mul(y, zinvsq)
-	yOut.Mod(yOut, curve.P)
-	return
-}
-
-func (curve *CurveParams) Add(x1, y1, x2, y2 *big.Int) (*big.Int, *big.Int) {
-	// If there is a dedicated constant-time implementation for this curve operation,
-	// use that instead of the generic one.
-	if specific, ok := matchesSpecificCurve(curve, p224, p384, p521); ok {
-		return specific.Add(x1, y1, x2, y2)
-	}
-
-	z1 := zForAffine(x1, y1)
-	z2 := zForAffine(x2, y2)
-	return curve.affineFromJacobian(curve.addJacobian(x1, y1, z1, x2, y2, z2))
-}
-
-// addJacobian takes two points in Jacobian coordinates, (x1, y1, z1) and
-// (x2, y2, z2) and returns their sum, also in Jacobian form.
-func (curve *CurveParams) addJacobian(x1, y1, z1, x2, y2, z2 *big.Int) (*big.Int, *big.Int, *big.Int) {
-	// See https://hyperelliptic.org/EFD/g1p/auto-shortw-jacobian-3.html#addition-add-2007-bl
-	x3, y3, z3 := new(big.Int), new(big.Int), new(big.Int)
-	if z1.Sign() == 0 {
-		x3.Set(x2)
-		y3.Set(y2)
-		z3.Set(z2)
-		return x3, y3, z3
-	}
-	if z2.Sign() == 0 {
-		x3.Set(x1)
-		y3.Set(y1)
-		z3.Set(z1)
-		return x3, y3, z3
-	}
-
-	z1z1 := new(big.Int).Mul(z1, z1)
-	z1z1.Mod(z1z1, curve.P)
-	z2z2 := new(big.Int).Mul(z2, z2)
-	z2z2.Mod(z2z2, curve.P)
-
-	u1 := new(big.Int).Mul(x1, z2z2)
-	u1.Mod(u1, curve.P)
-	u2 := new(big.Int).Mul(x2, z1z1)
-	u2.Mod(u2, curve.P)
-	h := new(big.Int).Sub(u2, u1)
-	xEqual := h.Sign() == 0
-	if h.Sign() == -1 {
-		h.Add(h, curve.P)
-	}
-	i := new(big.Int).Lsh(h, 1)
-	i.Mul(i, i)
-	j := new(big.Int).Mul(h, i)
-
-	s1 := new(big.Int).Mul(y1, z2)
-	s1.Mul(s1, z2z2)
-	s1.Mod(s1, curve.P)
-	s2 := new(big.Int).Mul(y2, z1)
-	s2.Mul(s2, z1z1)
-	s2.Mod(s2, curve.P)
-	r := new(big.Int).Sub(s2, s1)
-	if r.Sign() == -1 {
-		r.Add(r, curve.P)
-	}
-	yEqual := r.Sign() == 0
-	if xEqual && yEqual {
-		return curve.doubleJacobian(x1, y1, z1)
-	}
-	r.Lsh(r, 1)
-	v := new(big.Int).Mul(u1, i)
-
-	x3.Set(r)
-	x3.Mul(x3, x3)
-	x3.Sub(x3, j)
-	x3.Sub(x3, v)
-	x3.Sub(x3, v)
-	x3.Mod(x3, curve.P)
-
-	y3.Set(r)
-	v.Sub(v, x3)
-	y3.Mul(y3, v)
-	s1.Mul(s1, j)
-	s1.Lsh(s1, 1)
-	y3.Sub(y3, s1)
-	y3.Mod(y3, curve.P)
-
-	z3.Add(z1, z2)
-	z3.Mul(z3, z3)
-	z3.Sub(z3, z1z1)
-	z3.Sub(z3, z2z2)
-	z3.Mul(z3, h)
-	z3.Mod(z3, curve.P)
-
-	return x3, y3, z3
-}
-
-func (curve *CurveParams) Double(x1, y1 *big.Int) (*big.Int, *big.Int) {
-	// If there is a dedicated constant-time implementation for this curve operation,
-	// use that instead of the generic one.
-	if specific, ok := matchesSpecificCurve(curve, p224, p384, p521); ok {
-		return specific.Double(x1, y1)
-	}
-
-	z1 := zForAffine(x1, y1)
-	return curve.affineFromJacobian(curve.doubleJacobian(x1, y1, z1))
-}
-
-// doubleJacobian takes a point in Jacobian coordinates, (x, y, z), and
-// returns its double, also in Jacobian form.
-func (curve *CurveParams) doubleJacobian(x, y, z *big.Int) (*big.Int, *big.Int, *big.Int) {
-	// See https://hyperelliptic.org/EFD/g1p/auto-shortw-jacobian-3.html#doubling-dbl-2001-b
-	delta := new(big.Int).Mul(z, z)
-	delta.Mod(delta, curve.P)
-	gamma := new(big.Int).Mul(y, y)
-	gamma.Mod(gamma, curve.P)
-	alpha := new(big.Int).Sub(x, delta)
-	if alpha.Sign() == -1 {
-		alpha.Add(alpha, curve.P)
-	}
-	alpha2 := new(big.Int).Add(x, delta)
-	alpha.Mul(alpha, alpha2)
-	alpha2.Set(alpha)
-	alpha.Lsh(alpha, 1)
-	alpha.Add(alpha, alpha2)
-
-	beta := alpha2.Mul(x, gamma)
-
-	x3 := new(big.Int).Mul(alpha, alpha)
-	beta8 := new(big.Int).Lsh(beta, 3)
-	beta8.Mod(beta8, curve.P)
-	x3.Sub(x3, beta8)
-	if x3.Sign() == -1 {
-		x3.Add(x3, curve.P)
-	}
-	x3.Mod(x3, curve.P)
-
-	z3 := new(big.Int).Add(y, z)
-	z3.Mul(z3, z3)
-	z3.Sub(z3, gamma)
-	if z3.Sign() == -1 {
-		z3.Add(z3, curve.P)
-	}
-	z3.Sub(z3, delta)
-	if z3.Sign() == -1 {
-		z3.Add(z3, curve.P)
-	}
-	z3.Mod(z3, curve.P)
-
-	beta.Lsh(beta, 2)
-	beta.Sub(beta, x3)
-	if beta.Sign() == -1 {
-		beta.Add(beta, curve.P)
-	}
-	y3 := alpha.Mul(alpha, beta)
-
-	gamma.Mul(gamma, gamma)
-	gamma.Lsh(gamma, 3)
-	gamma.Mod(gamma, curve.P)
-
-	y3.Sub(y3, gamma)
-	if y3.Sign() == -1 {
-		y3.Add(y3, curve.P)
-	}
-	y3.Mod(y3, curve.P)
-
-	return x3, y3, z3
-}
-
-func (curve *CurveParams) ScalarMult(Bx, By *big.Int, k []byte) (*big.Int, *big.Int) {
-	// If there is a dedicated constant-time implementation for this curve operation,
-	// use that instead of the generic one.
-	if specific, ok := matchesSpecificCurve(curve, p224, p256, p384, p521); ok {
-		return specific.ScalarMult(Bx, By, k)
-	}
-
-	Bz := new(big.Int).SetInt64(1)
-	x, y, z := new(big.Int), new(big.Int), new(big.Int)
-
-	for _, byte := range k {
-		for bitNum := 0; bitNum < 8; bitNum++ {
-			x, y, z = curve.doubleJacobian(x, y, z)
-			if byte&0x80 == 0x80 {
-				x, y, z = curve.addJacobian(Bx, By, Bz, x, y, z)
-			}
-			byte <<= 1
-		}
-	}
-
-	return curve.affineFromJacobian(x, y, z)
-}
-
-func (curve *CurveParams) ScalarBaseMult(k []byte) (*big.Int, *big.Int) {
-	// If there is a dedicated constant-time implementation for this curve operation,
-	// use that instead of the generic one.
-	if specific, ok := matchesSpecificCurve(curve, p224, p256, p384, p521); ok {
-		return specific.ScalarBaseMult(k)
-	}
-
-	return curve.ScalarMult(curve.Gx, curve.Gy, k)
-}
-
-var mask = []byte{0xff, 0x1, 0x3, 0x7, 0xf, 0x1f, 0x3f, 0x7f}
-
-// GenerateKey returns a public/private key pair. The private key is
-// generated using the given reader, which must return random data.
-func GenerateKey(curve Curve, rand io.Reader) (priv []byte, x, y *big.Int, err error) {
-	N := curve.Params().N
-	bitSize := N.BitLen()
-	byteLen := (bitSize + 7) / 8
-	priv = make([]byte, byteLen)
-
-	for x == nil {
-		_, err = io.ReadFull(rand, priv)
-		if err != nil {
-			return
-		}
-		// We have to mask off any excess bits in the case that the size of the
-		// underlying field is not a whole number of bytes.
-		priv[0] &= mask[bitSize%8]
-		// This is because, in tests, rand will return all zeros and we don't
-		// want to get the point at infinity and loop forever.
-		priv[1] ^= 0x42
-
-		// If the scalar is out of range, sample another random number.
-		if new(big.Int).SetBytes(priv).Cmp(N) >= 0 {
-			continue
-		}
-
-		x, y = curve.ScalarBaseMult(priv)
-	}
-	return
-}
-
-// Marshal converts a point on the curve into the uncompressed form specified in
-// SEC 1, Version 2.0, Section 2.3.3. If the point is not on the curve (or is
-// the conventional point at infinity), the behavior is undefined.
-func Marshal(curve Curve, x, y *big.Int) []byte {
-	byteLen := (curve.Params().BitSize + 7) / 8
-
-	ret := make([]byte, 1+2*byteLen)
-	ret[0] = 4 // uncompressed point
-
-	x.FillBytes(ret[1 : 1+byteLen])
-	y.FillBytes(ret[1+byteLen : 1+2*byteLen])
-
-	return ret
-}
-
-// MarshalCompressed converts a point on the curve into the compressed form
-// specified in SEC 1, Version 2.0, Section 2.3.3. If the point is not on the
-// curve (or is the conventional point at infinity), the behavior is undefined.
-func MarshalCompressed(curve Curve, x, y *big.Int) []byte {
-	byteLen := (curve.Params().BitSize + 7) / 8
-	compressed := make([]byte, 1+byteLen)
-	compressed[0] = byte(y.Bit(0)) | 2
-	x.FillBytes(compressed[1:])
-	return compressed
-}
-
-// Unmarshal converts a point, serialized by Marshal, into an x, y pair. It is
-// an error if the point is not in uncompressed form, is not on the curve, or is
-// the point at infinity. On error, x = nil.
-func Unmarshal(curve Curve, data []byte) (x, y *big.Int) {
-	byteLen := (curve.Params().BitSize + 7) / 8
-	if len(data) != 1+2*byteLen {
-		return nil, nil
-	}
-	if data[0] != 4 { // uncompressed form
-		return nil, nil
-	}
-	p := curve.Params().P
-	x = new(big.Int).SetBytes(data[1 : 1+byteLen])
-	y = new(big.Int).SetBytes(data[1+byteLen:])
-	if x.Cmp(p) >= 0 || y.Cmp(p) >= 0 {
-		return nil, nil
-	}
-	if !curve.IsOnCurve(x, y) {
-		return nil, nil
-	}
-	return
-}
-
-// UnmarshalCompressed converts a point, serialized by MarshalCompressed, into
-// an x, y pair. It is an error if the point is not in compressed form, is not
-// on the curve, or is the point at infinity. On error, x = nil.
-func UnmarshalCompressed(curve Curve, data []byte) (x, y *big.Int) {
-	byteLen := (curve.Params().BitSize + 7) / 8
-	if len(data) != 1+byteLen {
-		return nil, nil
-	}
-	if data[0] != 2 && data[0] != 3 { // compressed form
-		return nil, nil
-	}
-	p := curve.Params().P
-	x = new(big.Int).SetBytes(data[1:])
-	if x.Cmp(p) >= 0 {
-		return nil, nil
-	}
-	// y² = x³ - 3x + b
-	y = curve.Params().polynomial(x)
-	y = y.ModSqrt(y, p)
-	if y == nil {
-		return nil, nil
-	}
-	if byte(y.Bit(0)) != data[0]&1 {
-		y.Neg(y).Mod(y, p)
-	}
-	if !curve.IsOnCurve(x, y) {
-		return nil, nil
-	}
-	return
-}
-
-var initonce sync.Once
-
-func initAll() {
-	initP224()
-	initP256()
-	initP384()
-	initP521()
-}
-
-// P224 returns a Curve which implements NIST P-224 (FIPS 186-3, section D.2.2),
-// also known as secp224r1. The CurveParams.Name of this Curve is "P-224".
-//
-// Multiple invocations of this function will return the same value, so it can
-// be used for equality checks and switch statements.
-//
-// The cryptographic operations are implemented using constant-time algorithms.
-func P224() Curve {
-	initonce.Do(initAll)
-	return p224
-}
-
-// P256 returns a Curve which implements NIST P-256 (FIPS 186-3, section D.2.3),
-// also known as secp256r1 or prime256v1. The CurveParams.Name of this Curve is
-// "P-256".
-//
-// Multiple invocations of this function will return the same value, so it can
-// be used for equality checks and switch statements.
-//
-// ScalarMult and ScalarBaseMult are implemented using constant-time algorithms.
-func P256() Curve {
-	initonce.Do(initAll)
-	return p256
-}
-
-// P384 returns a Curve which implements NIST P-384 (FIPS 186-3, section D.2.4),
-// also known as secp384r1. The CurveParams.Name of this Curve is "P-384".
-//
-// Multiple invocations of this function will return the same value, so it can
-// be used for equality checks and switch statements.
-//
-// The cryptographic operations are implemented using constant-time algorithms.
-func P384() Curve {
-	initonce.Do(initAll)
-	return p384
-}
-
-// P521 returns a Curve which implements NIST P-521 (FIPS 186-3, section D.2.5),
-// also known as secp521r1. The CurveParams.Name of this Curve is "P-521".
-//
-// Multiple invocations of this function will return the same value, so it can
-// be used for equality checks and switch statements.
-//
-// The cryptographic operations are implemented using constant-time algorithms.
-func P521() Curve {
-	initonce.Do(initAll)
-	return p521
-}
diff --git a/contrib/go/_std_1.18/src/crypto/elliptic/internal/fiat/p224_fiat64.go b/contrib/go/_std_1.18/src/crypto/elliptic/internal/fiat/p224_fiat64.go
deleted file mode 100644
index 4ece3e9220..0000000000
--- a/contrib/go/_std_1.18/src/crypto/elliptic/internal/fiat/p224_fiat64.go
+++ /dev/null
@@ -1,1429 +0,0 @@
-// Code generated by Fiat Cryptography. DO NOT EDIT.
-//
-// Autogenerated: word_by_word_montgomery --lang Go --no-wide-int --cmovznz-by-mul --relax-primitive-carry-to-bitwidth 32,64 --internal-static --public-function-case camelCase --public-type-case camelCase --private-function-case camelCase --private-type-case camelCase --doc-text-before-function-name '' --doc-newline-before-package-declaration --doc-prepend-header 'Code generated by Fiat Cryptography. DO NOT EDIT.' --package-name fiat --no-prefix-fiat p224 64 '2^224 - 2^96 + 1' mul square add sub one from_montgomery to_montgomery selectznz to_bytes from_bytes
-//
-// curve description: p224
-//
-// machine_wordsize = 64 (from "64")
-//
-// requested operations: mul, square, add, sub, one, from_montgomery, to_montgomery, selectznz, to_bytes, from_bytes
-//
-// m = 0xffffffffffffffffffffffffffffffff000000000000000000000001 (from "2^224 - 2^96 + 1")
-//
-//
-//
-// NOTE: In addition to the bounds specified above each function, all
-//
-//   functions synthesized for this Montgomery arithmetic require the
-//
-//   input to be strictly less than the prime modulus (m), and also
-//
-//   require the input to be in the unique saturated representation.
-//
-//   All functions also ensure that these two properties are true of
-//
-//   return values.
-//
-//
-//
-// Computed values:
-//
-//   eval z = z[0] + (z[1] << 64) + (z[2] << 128) + (z[3] << 192)
-//
-//   bytes_eval z = z[0] + (z[1] << 8) + (z[2] << 16) + (z[3] << 24) + (z[4] << 32) + (z[5] << 40) + (z[6] << 48) + (z[7] << 56) + (z[8] << 64) + (z[9] << 72) + (z[10] << 80) + (z[11] << 88) + (z[12] << 96) + (z[13] << 104) + (z[14] << 112) + (z[15] << 120) + (z[16] << 128) + (z[17] << 136) + (z[18] << 144) + (z[19] << 152) + (z[20] << 160) + (z[21] << 168) + (z[22] << 176) + (z[23] << 184) + (z[24] << 192) + (z[25] << 200) + (z[26] << 208) + (z[27] << 216)
-//
-//   twos_complement_eval z = let x1 := z[0] + (z[1] << 64) + (z[2] << 128) + (z[3] << 192) in
-//
-//                            if x1 & (2^256-1) < 2^255 then x1 & (2^256-1) else (x1 & (2^256-1)) - 2^256
-
-package fiat
-
-import "math/bits"
-
-type p224Uint1 uint64 // We use uint64 instead of a more narrow type for performance reasons; see https://github.com/mit-plv/fiat-crypto/pull/1006#issuecomment-892625927
-type p224Int1 int64   // We use uint64 instead of a more narrow type for performance reasons; see https://github.com/mit-plv/fiat-crypto/pull/1006#issuecomment-892625927
-
-// The type p224MontgomeryDomainFieldElement is a field element in the Montgomery domain.
-//
-// Bounds: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
-type p224MontgomeryDomainFieldElement [4]uint64
-
-// The type p224NonMontgomeryDomainFieldElement is a field element NOT in the Montgomery domain.
-//
-// Bounds: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
-type p224NonMontgomeryDomainFieldElement [4]uint64
-
-// p224CmovznzU64 is a single-word conditional move.
-//
-// Postconditions:
-//   out1 = (if arg1 = 0 then arg2 else arg3)
-//
-// Input Bounds:
-//   arg1: [0x0 ~> 0x1]
-//   arg2: [0x0 ~> 0xffffffffffffffff]
-//   arg3: [0x0 ~> 0xffffffffffffffff]
-// Output Bounds:
-//   out1: [0x0 ~> 0xffffffffffffffff]
-func p224CmovznzU64(out1 *uint64, arg1 p224Uint1, arg2 uint64, arg3 uint64) {
-	x1 := (uint64(arg1) * 0xffffffffffffffff)
-	x2 := ((x1 & arg3) | ((^x1) & arg2))
-	*out1 = x2
-}
-
-// p224Mul multiplies two field elements in the Montgomery domain.
-//
-// Preconditions:
-//   0 ≤ eval arg1 < m
-//   0 ≤ eval arg2 < m
-// Postconditions:
-//   eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) * eval (from_montgomery arg2)) mod m
-//   0 ≤ eval out1 < m
-//
-func p224Mul(out1 *p224MontgomeryDomainFieldElement, arg1 *p224MontgomeryDomainFieldElement, arg2 *p224MontgomeryDomainFieldElement) {
-	x1 := arg1[1]
-	x2 := arg1[2]
-	x3 := arg1[3]
-	x4 := arg1[0]
-	var x5 uint64
-	var x6 uint64
-	x6, x5 = bits.Mul64(x4, arg2[3])
-	var x7 uint64
-	var x8 uint64
-	x8, x7 = bits.Mul64(x4, arg2[2])
-	var x9 uint64
-	var x10 uint64
-	x10, x9 = bits.Mul64(x4, arg2[1])
-	var x11 uint64
-	var x12 uint64
-	x12, x11 = bits.Mul64(x4, arg2[0])
-	var x13 uint64
-	var x14 uint64
-	x13, x14 = bits.Add64(x12, x9, uint64(0x0))
-	var x15 uint64
-	var x16 uint64
-	x15, x16 = bits.Add64(x10, x7, uint64(p224Uint1(x14)))
-	var x17 uint64
-	var x18 uint64
-	x17, x18 = bits.Add64(x8, x5, uint64(p224Uint1(x16)))
-	x19 := (uint64(p224Uint1(x18)) + x6)
-	var x20 uint64
-	_, x20 = bits.Mul64(x11, 0xffffffffffffffff)
-	var x22 uint64
-	var x23 uint64
-	x23, x22 = bits.Mul64(x20, 0xffffffff)
-	var x24 uint64
-	var x25 uint64
-	x25, x24 = bits.Mul64(x20, 0xffffffffffffffff)
-	var x26 uint64
-	var x27 uint64
-	x27, x26 = bits.Mul64(x20, 0xffffffff00000000)
-	var x28 uint64
-	var x29 uint64
-	x28, x29 = bits.Add64(x27, x24, uint64(0x0))
-	var x30 uint64
-	var x31 uint64
-	x30, x31 = bits.Add64(x25, x22, uint64(p224Uint1(x29)))
-	x32 := (uint64(p224Uint1(x31)) + x23)
-	var x34 uint64
-	_, x34 = bits.Add64(x11, x20, uint64(0x0))
-	var x35 uint64
-	var x36 uint64
-	x35, x36 = bits.Add64(x13, x26, uint64(p224Uint1(x34)))
-	var x37 uint64
-	var x38 uint64
-	x37, x38 = bits.Add64(x15, x28, uint64(p224Uint1(x36)))
-	var x39 uint64
-	var x40 uint64
-	x39, x40 = bits.Add64(x17, x30, uint64(p224Uint1(x38)))
-	var x41 uint64
-	var x42 uint64
-	x41, x42 = bits.Add64(x19, x32, uint64(p224Uint1(x40)))
-	var x43 uint64
-	var x44 uint64
-	x44, x43 = bits.Mul64(x1, arg2[3])
-	var x45 uint64
-	var x46 uint64
-	x46, x45 = bits.Mul64(x1, arg2[2])
-	var x47 uint64
-	var x48 uint64
-	x48, x47 = bits.Mul64(x1, arg2[1])
-	var x49 uint64
-	var x50 uint64
-	x50, x49 = bits.Mul64(x1, arg2[0])
-	var x51 uint64
-	var x52 uint64
-	x51, x52 = bits.Add64(x50, x47, uint64(0x0))
-	var x53 uint64
-	var x54 uint64
-	x53, x54 = bits.Add64(x48, x45, uint64(p224Uint1(x52)))
-	var x55 uint64
-	var x56 uint64
-	x55, x56 = bits.Add64(x46, x43, uint64(p224Uint1(x54)))
-	x57 := (uint64(p224Uint1(x56)) + x44)
-	var x58 uint64
-	var x59 uint64
-	x58, x59 = bits.Add64(x35, x49, uint64(0x0))
-	var x60 uint64
-	var x61 uint64
-	x60, x61 = bits.Add64(x37, x51, uint64(p224Uint1(x59)))
-	var x62 uint64
-	var x63 uint64
-	x62, x63 = bits.Add64(x39, x53, uint64(p224Uint1(x61)))
-	var x64 uint64
-	var x65 uint64
-	x64, x65 = bits.Add64(x41, x55, uint64(p224Uint1(x63)))
-	var x66 uint64
-	var x67 uint64
-	x66, x67 = bits.Add64(uint64(p224Uint1(x42)), x57, uint64(p224Uint1(x65)))
-	var x68 uint64
-	_, x68 = bits.Mul64(x58, 0xffffffffffffffff)
-	var x70 uint64
-	var x71 uint64
-	x71, x70 = bits.Mul64(x68, 0xffffffff)
-	var x72 uint64
-	var x73 uint64
-	x73, x72 = bits.Mul64(x68, 0xffffffffffffffff)
-	var x74 uint64
-	var x75 uint64
-	x75, x74 = bits.Mul64(x68, 0xffffffff00000000)
-	var x76 uint64
-	var x77 uint64
-	x76, x77 = bits.Add64(x75, x72, uint64(0x0))
-	var x78 uint64
-	var x79 uint64
-	x78, x79 = bits.Add64(x73, x70, uint64(p224Uint1(x77)))
-	x80 := (uint64(p224Uint1(x79)) + x71)
-	var x82 uint64
-	_, x82 = bits.Add64(x58, x68, uint64(0x0))
-	var x83 uint64
-	var x84 uint64
-	x83, x84 = bits.Add64(x60, x74, uint64(p224Uint1(x82)))
-	var x85 uint64
-	var x86 uint64
-	x85, x86 = bits.Add64(x62, x76, uint64(p224Uint1(x84)))
-	var x87 uint64
-	var x88 uint64
-	x87, x88 = bits.Add64(x64, x78, uint64(p224Uint1(x86)))
-	var x89 uint64
-	var x90 uint64
-	x89, x90 = bits.Add64(x66, x80, uint64(p224Uint1(x88)))
-	x91 := (uint64(p224Uint1(x90)) + uint64(p224Uint1(x67)))
-	var x92 uint64
-	var x93 uint64
-	x93, x92 = bits.Mul64(x2, arg2[3])
-	var x94 uint64
-	var x95 uint64
-	x95, x94 = bits.Mul64(x2, arg2[2])
-	var x96 uint64
-	var x97 uint64
-	x97, x96 = bits.Mul64(x2, arg2[1])
-	var x98 uint64
-	var x99 uint64
-	x99, x98 = bits.Mul64(x2, arg2[0])
-	var x100 uint64
-	var x101 uint64
-	x100, x101 = bits.Add64(x99, x96, uint64(0x0))
-	var x102 uint64
-	var x103 uint64
-	x102, x103 = bits.Add64(x97, x94, uint64(p224Uint1(x101)))
-	var x104 uint64
-	var x105 uint64
-	x104, x105 = bits.Add64(x95, x92, uint64(p224Uint1(x103)))
-	x106 := (uint64(p224Uint1(x105)) + x93)
-	var x107 uint64
-	var x108 uint64
-	x107, x108 = bits.Add64(x83, x98, uint64(0x0))
-	var x109 uint64
-	var x110 uint64
-	x109, x110 = bits.Add64(x85, x100, uint64(p224Uint1(x108)))
-	var x111 uint64
-	var x112 uint64
-	x111, x112 = bits.Add64(x87, x102, uint64(p224Uint1(x110)))
-	var x113 uint64
-	var x114 uint64
-	x113, x114 = bits.Add64(x89, x104, uint64(p224Uint1(x112)))
-	var x115 uint64
-	var x116 uint64
-	x115, x116 = bits.Add64(x91, x106, uint64(p224Uint1(x114)))
-	var x117 uint64
-	_, x117 = bits.Mul64(x107, 0xffffffffffffffff)
-	var x119 uint64
-	var x120 uint64
-	x120, x119 = bits.Mul64(x117, 0xffffffff)
-	var x121 uint64
-	var x122 uint64
-	x122, x121 = bits.Mul64(x117, 0xffffffffffffffff)
-	var x123 uint64
-	var x124 uint64
-	x124, x123 = bits.Mul64(x117, 0xffffffff00000000)
-	var x125 uint64
-	var x126 uint64
-	x125, x126 = bits.Add64(x124, x121, uint64(0x0))
-	var x127 uint64
-	var x128 uint64
-	x127, x128 = bits.Add64(x122, x119, uint64(p224Uint1(x126)))
-	x129 := (uint64(p224Uint1(x128)) + x120)
-	var x131 uint64
-	_, x131 = bits.Add64(x107, x117, uint64(0x0))
-	var x132 uint64
-	var x133 uint64
-	x132, x133 = bits.Add64(x109, x123, uint64(p224Uint1(x131)))
-	var x134 uint64
-	var x135 uint64
-	x134, x135 = bits.Add64(x111, x125, uint64(p224Uint1(x133)))
-	var x136 uint64
-	var x137 uint64
-	x136, x137 = bits.Add64(x113, x127, uint64(p224Uint1(x135)))
-	var x138 uint64
-	var x139 uint64
-	x138, x139 = bits.Add64(x115, x129, uint64(p224Uint1(x137)))
-	x140 := (uint64(p224Uint1(x139)) + uint64(p224Uint1(x116)))
-	var x141 uint64
-	var x142 uint64
-	x142, x141 = bits.Mul64(x3, arg2[3])
-	var x143 uint64
-	var x144 uint64
-	x144, x143 = bits.Mul64(x3, arg2[2])
-	var x145 uint64
-	var x146 uint64
-	x146, x145 = bits.Mul64(x3, arg2[1])
-	var x147 uint64
-	var x148 uint64
-	x148, x147 = bits.Mul64(x3, arg2[0])
-	var x149 uint64
-	var x150 uint64
-	x149, x150 = bits.Add64(x148, x145, uint64(0x0))
-	var x151 uint64
-	var x152 uint64
-	x151, x152 = bits.Add64(x146, x143, uint64(p224Uint1(x150)))
-	var x153 uint64
-	var x154 uint64
-	x153, x154 = bits.Add64(x144, x141, uint64(p224Uint1(x152)))
-	x155 := (uint64(p224Uint1(x154)) + x142)
-	var x156 uint64
-	var x157 uint64
-	x156, x157 = bits.Add64(x132, x147, uint64(0x0))
-	var x158 uint64
-	var x159 uint64
-	x158, x159 = bits.Add64(x134, x149, uint64(p224Uint1(x157)))
-	var x160 uint64
-	var x161 uint64
-	x160, x161 = bits.Add64(x136, x151, uint64(p224Uint1(x159)))
-	var x162 uint64
-	var x163 uint64
-	x162, x163 = bits.Add64(x138, x153, uint64(p224Uint1(x161)))
-	var x164 uint64
-	var x165 uint64
-	x164, x165 = bits.Add64(x140, x155, uint64(p224Uint1(x163)))
-	var x166 uint64
-	_, x166 = bits.Mul64(x156, 0xffffffffffffffff)
-	var x168 uint64
-	var x169 uint64
-	x169, x168 = bits.Mul64(x166, 0xffffffff)
-	var x170 uint64
-	var x171 uint64
-	x171, x170 = bits.Mul64(x166, 0xffffffffffffffff)
-	var x172 uint64
-	var x173 uint64
-	x173, x172 = bits.Mul64(x166, 0xffffffff00000000)
-	var x174 uint64
-	var x175 uint64
-	x174, x175 = bits.Add64(x173, x170, uint64(0x0))
-	var x176 uint64
-	var x177 uint64
-	x176, x177 = bits.Add64(x171, x168, uint64(p224Uint1(x175)))
-	x178 := (uint64(p224Uint1(x177)) + x169)
-	var x180 uint64
-	_, x180 = bits.Add64(x156, x166, uint64(0x0))
-	var x181 uint64
-	var x182 uint64
-	x181, x182 = bits.Add64(x158, x172, uint64(p224Uint1(x180)))
-	var x183 uint64
-	var x184 uint64
-	x183, x184 = bits.Add64(x160, x174, uint64(p224Uint1(x182)))
-	var x185 uint64
-	var x186 uint64
-	x185, x186 = bits.Add64(x162, x176, uint64(p224Uint1(x184)))
-	var x187 uint64
-	var x188 uint64
-	x187, x188 = bits.Add64(x164, x178, uint64(p224Uint1(x186)))
-	x189 := (uint64(p224Uint1(x188)) + uint64(p224Uint1(x165)))
-	var x190 uint64
-	var x191 uint64
-	x190, x191 = bits.Sub64(x181, uint64(0x1), uint64(0x0))
-	var x192 uint64
-	var x193 uint64
-	x192, x193 = bits.Sub64(x183, 0xffffffff00000000, uint64(p224Uint1(x191)))
-	var x194 uint64
-	var x195 uint64
-	x194, x195 = bits.Sub64(x185, 0xffffffffffffffff, uint64(p224Uint1(x193)))
-	var x196 uint64
-	var x197 uint64
-	x196, x197 = bits.Sub64(x187, 0xffffffff, uint64(p224Uint1(x195)))
-	var x199 uint64
-	_, x199 = bits.Sub64(x189, uint64(0x0), uint64(p224Uint1(x197)))
-	var x200 uint64
-	p224CmovznzU64(&x200, p224Uint1(x199), x190, x181)
-	var x201 uint64
-	p224CmovznzU64(&x201, p224Uint1(x199), x192, x183)
-	var x202 uint64
-	p224CmovznzU64(&x202, p224Uint1(x199), x194, x185)
-	var x203 uint64
-	p224CmovznzU64(&x203, p224Uint1(x199), x196, x187)
-	out1[0] = x200
-	out1[1] = x201
-	out1[2] = x202
-	out1[3] = x203
-}
-
-// p224Square squares a field element in the Montgomery domain.
-//
-// Preconditions:
-//   0 ≤ eval arg1 < m
-// Postconditions:
-//   eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) * eval (from_montgomery arg1)) mod m
-//   0 ≤ eval out1 < m
-//
-func p224Square(out1 *p224MontgomeryDomainFieldElement, arg1 *p224MontgomeryDomainFieldElement) {
-	x1 := arg1[1]
-	x2 := arg1[2]
-	x3 := arg1[3]
-	x4 := arg1[0]
-	var x5 uint64
-	var x6 uint64
-	x6, x5 = bits.Mul64(x4, arg1[3])
-	var x7 uint64
-	var x8 uint64
-	x8, x7 = bits.Mul64(x4, arg1[2])
-	var x9 uint64
-	var x10 uint64
-	x10, x9 = bits.Mul64(x4, arg1[1])
-	var x11 uint64
-	var x12 uint64
-	x12, x11 = bits.Mul64(x4, arg1[0])
-	var x13 uint64
-	var x14 uint64
-	x13, x14 = bits.Add64(x12, x9, uint64(0x0))
-	var x15 uint64
-	var x16 uint64
-	x15, x16 = bits.Add64(x10, x7, uint64(p224Uint1(x14)))
-	var x17 uint64
-	var x18 uint64
-	x17, x18 = bits.Add64(x8, x5, uint64(p224Uint1(x16)))
-	x19 := (uint64(p224Uint1(x18)) + x6)
-	var x20 uint64
-	_, x20 = bits.Mul64(x11, 0xffffffffffffffff)
-	var x22 uint64
-	var x23 uint64
-	x23, x22 = bits.Mul64(x20, 0xffffffff)
-	var x24 uint64
-	var x25 uint64
-	x25, x24 = bits.Mul64(x20, 0xffffffffffffffff)
-	var x26 uint64
-	var x27 uint64
-	x27, x26 = bits.Mul64(x20, 0xffffffff00000000)
-	var x28 uint64
-	var x29 uint64
-	x28, x29 = bits.Add64(x27, x24, uint64(0x0))
-	var x30 uint64
-	var x31 uint64
-	x30, x31 = bits.Add64(x25, x22, uint64(p224Uint1(x29)))
-	x32 := (uint64(p224Uint1(x31)) + x23)
-	var x34 uint64
-	_, x34 = bits.Add64(x11, x20, uint64(0x0))
-	var x35 uint64
-	var x36 uint64
-	x35, x36 = bits.Add64(x13, x26, uint64(p224Uint1(x34)))
-	var x37 uint64
-	var x38 uint64
-	x37, x38 = bits.Add64(x15, x28, uint64(p224Uint1(x36)))
-	var x39 uint64
-	var x40 uint64
-	x39, x40 = bits.Add64(x17, x30, uint64(p224Uint1(x38)))
-	var x41 uint64
-	var x42 uint64
-	x41, x42 = bits.Add64(x19, x32, uint64(p224Uint1(x40)))
-	var x43 uint64
-	var x44 uint64
-	x44, x43 = bits.Mul64(x1, arg1[3])
-	var x45 uint64
-	var x46 uint64
-	x46, x45 = bits.Mul64(x1, arg1[2])
-	var x47 uint64
-	var x48 uint64
-	x48, x47 = bits.Mul64(x1, arg1[1])
-	var x49 uint64
-	var x50 uint64
-	x50, x49 = bits.Mul64(x1, arg1[0])
-	var x51 uint64
-	var x52 uint64
-	x51, x52 = bits.Add64(x50, x47, uint64(0x0))
-	var x53 uint64
-	var x54 uint64
-	x53, x54 = bits.Add64(x48, x45, uint64(p224Uint1(x52)))
-	var x55 uint64
-	var x56 uint64
-	x55, x56 = bits.Add64(x46, x43, uint64(p224Uint1(x54)))
-	x57 := (uint64(p224Uint1(x56)) + x44)
-	var x58 uint64
-	var x59 uint64
-	x58, x59 = bits.Add64(x35, x49, uint64(0x0))
-	var x60 uint64
-	var x61 uint64
-	x60, x61 = bits.Add64(x37, x51, uint64(p224Uint1(x59)))
-	var x62 uint64
-	var x63 uint64
-	x62, x63 = bits.Add64(x39, x53, uint64(p224Uint1(x61)))
-	var x64 uint64
-	var x65 uint64
-	x64, x65 = bits.Add64(x41, x55, uint64(p224Uint1(x63)))
-	var x66 uint64
-	var x67 uint64
-	x66, x67 = bits.Add64(uint64(p224Uint1(x42)), x57, uint64(p224Uint1(x65)))
-	var x68 uint64
-	_, x68 = bits.Mul64(x58, 0xffffffffffffffff)
-	var x70 uint64
-	var x71 uint64
-	x71, x70 = bits.Mul64(x68, 0xffffffff)
-	var x72 uint64
-	var x73 uint64
-	x73, x72 = bits.Mul64(x68, 0xffffffffffffffff)
-	var x74 uint64
-	var x75 uint64
-	x75, x74 = bits.Mul64(x68, 0xffffffff00000000)
-	var x76 uint64
-	var x77 uint64
-	x76, x77 = bits.Add64(x75, x72, uint64(0x0))
-	var x78 uint64
-	var x79 uint64
-	x78, x79 = bits.Add64(x73, x70, uint64(p224Uint1(x77)))
-	x80 := (uint64(p224Uint1(x79)) + x71)
-	var x82 uint64
-	_, x82 = bits.Add64(x58, x68, uint64(0x0))
-	var x83 uint64
-	var x84 uint64
-	x83, x84 = bits.Add64(x60, x74, uint64(p224Uint1(x82)))
-	var x85 uint64
-	var x86 uint64
-	x85, x86 = bits.Add64(x62, x76, uint64(p224Uint1(x84)))
-	var x87 uint64
-	var x88 uint64
-	x87, x88 = bits.Add64(x64, x78, uint64(p224Uint1(x86)))
-	var x89 uint64
-	var x90 uint64
-	x89, x90 = bits.Add64(x66, x80, uint64(p224Uint1(x88)))
-	x91 := (uint64(p224Uint1(x90)) + uint64(p224Uint1(x67)))
-	var x92 uint64
-	var x93 uint64
-	x93, x92 = bits.Mul64(x2, arg1[3])
-	var x94 uint64
-	var x95 uint64
-	x95, x94 = bits.Mul64(x2, arg1[2])
-	var x96 uint64
-	var x97 uint64
-	x97, x96 = bits.Mul64(x2, arg1[1])
-	var x98 uint64
-	var x99 uint64
-	x99, x98 = bits.Mul64(x2, arg1[0])
-	var x100 uint64
-	var x101 uint64
-	x100, x101 = bits.Add64(x99, x96, uint64(0x0))
-	var x102 uint64
-	var x103 uint64
-	x102, x103 = bits.Add64(x97, x94, uint64(p224Uint1(x101)))
-	var x104 uint64
-	var x105 uint64
-	x104, x105 = bits.Add64(x95, x92, uint64(p224Uint1(x103)))
-	x106 := (uint64(p224Uint1(x105)) + x93)
-	var x107 uint64
-	var x108 uint64
-	x107, x108 = bits.Add64(x83, x98, uint64(0x0))
-	var x109 uint64
-	var x110 uint64
-	x109, x110 = bits.Add64(x85, x100, uint64(p224Uint1(x108)))
-	var x111 uint64
-	var x112 uint64
-	x111, x112 = bits.Add64(x87, x102, uint64(p224Uint1(x110)))
-	var x113 uint64
-	var x114 uint64
-	x113, x114 = bits.Add64(x89, x104, uint64(p224Uint1(x112)))
-	var x115 uint64
-	var x116 uint64
-	x115, x116 = bits.Add64(x91, x106, uint64(p224Uint1(x114)))
-	var x117 uint64
-	_, x117 = bits.Mul64(x107, 0xffffffffffffffff)
-	var x119 uint64
-	var x120 uint64
-	x120, x119 = bits.Mul64(x117, 0xffffffff)
-	var x121 uint64
-	var x122 uint64
-	x122, x121 = bits.Mul64(x117, 0xffffffffffffffff)
-	var x123 uint64
-	var x124 uint64
-	x124, x123 = bits.Mul64(x117, 0xffffffff00000000)
-	var x125 uint64
-	var x126 uint64
-	x125, x126 = bits.Add64(x124, x121, uint64(0x0))
-	var x127 uint64
-	var x128 uint64
-	x127, x128 = bits.Add64(x122, x119, uint64(p224Uint1(x126)))
-	x129 := (uint64(p224Uint1(x128)) + x120)
-	var x131 uint64
-	_, x131 = bits.Add64(x107, x117, uint64(0x0))
-	var x132 uint64
-	var x133 uint64
-	x132, x133 = bits.Add64(x109, x123, uint64(p224Uint1(x131)))
-	var x134 uint64
-	var x135 uint64
-	x134, x135 = bits.Add64(x111, x125, uint64(p224Uint1(x133)))
-	var x136 uint64
-	var x137 uint64
-	x136, x137 = bits.Add64(x113, x127, uint64(p224Uint1(x135)))
-	var x138 uint64
-	var x139 uint64
-	x138, x139 = bits.Add64(x115, x129, uint64(p224Uint1(x137)))
-	x140 := (uint64(p224Uint1(x139)) + uint64(p224Uint1(x116)))
-	var x141 uint64
-	var x142 uint64
-	x142, x141 = bits.Mul64(x3, arg1[3])
-	var x143 uint64
-	var x144 uint64
-	x144, x143 = bits.Mul64(x3, arg1[2])
-	var x145 uint64
-	var x146 uint64
-	x146, x145 = bits.Mul64(x3, arg1[1])
-	var x147 uint64
-	var x148 uint64
-	x148, x147 = bits.Mul64(x3, arg1[0])
-	var x149 uint64
-	var x150 uint64
-	x149, x150 = bits.Add64(x148, x145, uint64(0x0))
-	var x151 uint64
-	var x152 uint64
-	x151, x152 = bits.Add64(x146, x143, uint64(p224Uint1(x150)))
-	var x153 uint64
-	var x154 uint64
-	x153, x154 = bits.Add64(x144, x141, uint64(p224Uint1(x152)))
-	x155 := (uint64(p224Uint1(x154)) + x142)
-	var x156 uint64
-	var x157 uint64
-	x156, x157 = bits.Add64(x132, x147, uint64(0x0))
-	var x158 uint64
-	var x159 uint64
-	x158, x159 = bits.Add64(x134, x149, uint64(p224Uint1(x157)))
-	var x160 uint64
-	var x161 uint64
-	x160, x161 = bits.Add64(x136, x151, uint64(p224Uint1(x159)))
-	var x162 uint64
-	var x163 uint64
-	x162, x163 = bits.Add64(x138, x153, uint64(p224Uint1(x161)))
-	var x164 uint64
-	var x165 uint64
-	x164, x165 = bits.Add64(x140, x155, uint64(p224Uint1(x163)))
-	var x166 uint64
-	_, x166 = bits.Mul64(x156, 0xffffffffffffffff)
-	var x168 uint64
-	var x169 uint64
-	x169, x168 = bits.Mul64(x166, 0xffffffff)
-	var x170 uint64
-	var x171 uint64
-	x171, x170 = bits.Mul64(x166, 0xffffffffffffffff)
-	var x172 uint64
-	var x173 uint64
-	x173, x172 = bits.Mul64(x166, 0xffffffff00000000)
-	var x174 uint64
-	var x175 uint64
-	x174, x175 = bits.Add64(x173, x170, uint64(0x0))
-	var x176 uint64
-	var x177 uint64
-	x176, x177 = bits.Add64(x171, x168, uint64(p224Uint1(x175)))
-	x178 := (uint64(p224Uint1(x177)) + x169)
-	var x180 uint64
-	_, x180 = bits.Add64(x156, x166, uint64(0x0))
-	var x181 uint64
-	var x182 uint64
-	x181, x182 = bits.Add64(x158, x172, uint64(p224Uint1(x180)))
-	var x183 uint64
-	var x184 uint64
-	x183, x184 = bits.Add64(x160, x174, uint64(p224Uint1(x182)))
-	var x185 uint64
-	var x186 uint64
-	x185, x186 = bits.Add64(x162, x176, uint64(p224Uint1(x184)))
-	var x187 uint64
-	var x188 uint64
-	x187, x188 = bits.Add64(x164, x178, uint64(p224Uint1(x186)))
-	x189 := (uint64(p224Uint1(x188)) + uint64(p224Uint1(x165)))
-	var x190 uint64
-	var x191 uint64
-	x190, x191 = bits.Sub64(x181, uint64(0x1), uint64(0x0))
-	var x192 uint64
-	var x193 uint64
-	x192, x193 = bits.Sub64(x183, 0xffffffff00000000, uint64(p224Uint1(x191)))
-	var x194 uint64
-	var x195 uint64
-	x194, x195 = bits.Sub64(x185, 0xffffffffffffffff, uint64(p224Uint1(x193)))
-	var x196 uint64
-	var x197 uint64
-	x196, x197 = bits.Sub64(x187, 0xffffffff, uint64(p224Uint1(x195)))
-	var x199 uint64
-	_, x199 = bits.Sub64(x189, uint64(0x0), uint64(p224Uint1(x197)))
-	var x200 uint64
-	p224CmovznzU64(&x200, p224Uint1(x199), x190, x181)
-	var x201 uint64
-	p224CmovznzU64(&x201, p224Uint1(x199), x192, x183)
-	var x202 uint64
-	p224CmovznzU64(&x202, p224Uint1(x199), x194, x185)
-	var x203 uint64
-	p224CmovznzU64(&x203, p224Uint1(x199), x196, x187)
-	out1[0] = x200
-	out1[1] = x201
-	out1[2] = x202
-	out1[3] = x203
-}
-
-// p224Add adds two field elements in the Montgomery domain.
-//
-// Preconditions:
-//   0 ≤ eval arg1 < m
-//   0 ≤ eval arg2 < m
-// Postconditions:
-//   eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) + eval (from_montgomery arg2)) mod m
-//   0 ≤ eval out1 < m
-//
-func p224Add(out1 *p224MontgomeryDomainFieldElement, arg1 *p224MontgomeryDomainFieldElement, arg2 *p224MontgomeryDomainFieldElement) {
-	var x1 uint64
-	var x2 uint64
-	x1, x2 = bits.Add64(arg1[0], arg2[0], uint64(0x0))
-	var x3 uint64
-	var x4 uint64
-	x3, x4 = bits.Add64(arg1[1], arg2[1], uint64(p224Uint1(x2)))
-	var x5 uint64
-	var x6 uint64
-	x5, x6 = bits.Add64(arg1[2], arg2[2], uint64(p224Uint1(x4)))
-	var x7 uint64
-	var x8 uint64
-	x7, x8 = bits.Add64(arg1[3], arg2[3], uint64(p224Uint1(x6)))
-	var x9 uint64
-	var x10 uint64
-	x9, x10 = bits.Sub64(x1, uint64(0x1), uint64(0x0))
-	var x11 uint64
-	var x12 uint64
-	x11, x12 = bits.Sub64(x3, 0xffffffff00000000, uint64(p224Uint1(x10)))
-	var x13 uint64
-	var x14 uint64
-	x13, x14 = bits.Sub64(x5, 0xffffffffffffffff, uint64(p224Uint1(x12)))
-	var x15 uint64
-	var x16 uint64
-	x15, x16 = bits.Sub64(x7, 0xffffffff, uint64(p224Uint1(x14)))
-	var x18 uint64
-	_, x18 = bits.Sub64(uint64(p224Uint1(x8)), uint64(0x0), uint64(p224Uint1(x16)))
-	var x19 uint64
-	p224CmovznzU64(&x19, p224Uint1(x18), x9, x1)
-	var x20 uint64
-	p224CmovznzU64(&x20, p224Uint1(x18), x11, x3)
-	var x21 uint64
-	p224CmovznzU64(&x21, p224Uint1(x18), x13, x5)
-	var x22 uint64
-	p224CmovznzU64(&x22, p224Uint1(x18), x15, x7)
-	out1[0] = x19
-	out1[1] = x20
-	out1[2] = x21
-	out1[3] = x22
-}
-
-// p224Sub subtracts two field elements in the Montgomery domain.
-//
-// Preconditions:
-//   0 ≤ eval arg1 < m
-//   0 ≤ eval arg2 < m
-// Postconditions:
-//   eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) - eval (from_montgomery arg2)) mod m
-//   0 ≤ eval out1 < m
-//
-func p224Sub(out1 *p224MontgomeryDomainFieldElement, arg1 *p224MontgomeryDomainFieldElement, arg2 *p224MontgomeryDomainFieldElement) {
-	var x1 uint64
-	var x2 uint64
-	x1, x2 = bits.Sub64(arg1[0], arg2[0], uint64(0x0))
-	var x3 uint64
-	var x4 uint64
-	x3, x4 = bits.Sub64(arg1[1], arg2[1], uint64(p224Uint1(x2)))
-	var x5 uint64
-	var x6 uint64
-	x5, x6 = bits.Sub64(arg1[2], arg2[2], uint64(p224Uint1(x4)))
-	var x7 uint64
-	var x8 uint64
-	x7, x8 = bits.Sub64(arg1[3], arg2[3], uint64(p224Uint1(x6)))
-	var x9 uint64
-	p224CmovznzU64(&x9, p224Uint1(x8), uint64(0x0), 0xffffffffffffffff)
-	var x10 uint64
-	var x11 uint64
-	x10, x11 = bits.Add64(x1, uint64((p224Uint1(x9) & 0x1)), uint64(0x0))
-	var x12 uint64
-	var x13 uint64
-	x12, x13 = bits.Add64(x3, (x9 & 0xffffffff00000000), uint64(p224Uint1(x11)))
-	var x14 uint64
-	var x15 uint64
-	x14, x15 = bits.Add64(x5, x9, uint64(p224Uint1(x13)))
-	var x16 uint64
-	x16, _ = bits.Add64(x7, (x9 & 0xffffffff), uint64(p224Uint1(x15)))
-	out1[0] = x10
-	out1[1] = x12
-	out1[2] = x14
-	out1[3] = x16
-}
-
-// p224SetOne returns the field element one in the Montgomery domain.
-//
-// Postconditions:
-//   eval (from_montgomery out1) mod m = 1 mod m
-//   0 ≤ eval out1 < m
-//
-func p224SetOne(out1 *p224MontgomeryDomainFieldElement) {
-	out1[0] = 0xffffffff00000000
-	out1[1] = 0xffffffffffffffff
-	out1[2] = uint64(0x0)
-	out1[3] = uint64(0x0)
-}
-
-// p224FromMontgomery translates a field element out of the Montgomery domain.
-//
-// Preconditions:
-//   0 ≤ eval arg1 < m
-// Postconditions:
-//   eval out1 mod m = (eval arg1 * ((2^64)⁻¹ mod m)^4) mod m
-//   0 ≤ eval out1 < m
-//
-func p224FromMontgomery(out1 *p224NonMontgomeryDomainFieldElement, arg1 *p224MontgomeryDomainFieldElement) {
-	x1 := arg1[0]
-	var x2 uint64
-	_, x2 = bits.Mul64(x1, 0xffffffffffffffff)
-	var x4 uint64
-	var x5 uint64
-	x5, x4 = bits.Mul64(x2, 0xffffffff)
-	var x6 uint64
-	var x7 uint64
-	x7, x6 = bits.Mul64(x2, 0xffffffffffffffff)
-	var x8 uint64
-	var x9 uint64
-	x9, x8 = bits.Mul64(x2, 0xffffffff00000000)
-	var x10 uint64
-	var x11 uint64
-	x10, x11 = bits.Add64(x9, x6, uint64(0x0))
-	var x12 uint64
-	var x13 uint64
-	x12, x13 = bits.Add64(x7, x4, uint64(p224Uint1(x11)))
-	var x15 uint64
-	_, x15 = bits.Add64(x1, x2, uint64(0x0))
-	var x16 uint64
-	var x17 uint64
-	x16, x17 = bits.Add64(uint64(0x0), x8, uint64(p224Uint1(x15)))
-	var x18 uint64
-	var x19 uint64
-	x18, x19 = bits.Add64(uint64(0x0), x10, uint64(p224Uint1(x17)))
-	var x20 uint64
-	var x21 uint64
-	x20, x21 = bits.Add64(uint64(0x0), x12, uint64(p224Uint1(x19)))
-	var x22 uint64
-	var x23 uint64
-	x22, x23 = bits.Add64(x16, arg1[1], uint64(0x0))
-	var x24 uint64
-	var x25 uint64
-	x24, x25 = bits.Add64(x18, uint64(0x0), uint64(p224Uint1(x23)))
-	var x26 uint64
-	var x27 uint64
-	x26, x27 = bits.Add64(x20, uint64(0x0), uint64(p224Uint1(x25)))
-	var x28 uint64
-	_, x28 = bits.Mul64(x22, 0xffffffffffffffff)
-	var x30 uint64
-	var x31 uint64
-	x31, x30 = bits.Mul64(x28, 0xffffffff)
-	var x32 uint64
-	var x33 uint64
-	x33, x32 = bits.Mul64(x28, 0xffffffffffffffff)
-	var x34 uint64
-	var x35 uint64
-	x35, x34 = bits.Mul64(x28, 0xffffffff00000000)
-	var x36 uint64
-	var x37 uint64
-	x36, x37 = bits.Add64(x35, x32, uint64(0x0))
-	var x38 uint64
-	var x39 uint64
-	x38, x39 = bits.Add64(x33, x30, uint64(p224Uint1(x37)))
-	var x41 uint64
-	_, x41 = bits.Add64(x22, x28, uint64(0x0))
-	var x42 uint64
-	var x43 uint64
-	x42, x43 = bits.Add64(x24, x34, uint64(p224Uint1(x41)))
-	var x44 uint64
-	var x45 uint64
-	x44, x45 = bits.Add64(x26, x36, uint64(p224Uint1(x43)))
-	var x46 uint64
-	var x47 uint64
-	x46, x47 = bits.Add64((uint64(p224Uint1(x27)) + (uint64(p224Uint1(x21)) + (uint64(p224Uint1(x13)) + x5))), x38, uint64(p224Uint1(x45)))
-	var x48 uint64
-	var x49 uint64
-	x48, x49 = bits.Add64(x42, arg1[2], uint64(0x0))
-	var x50 uint64
-	var x51 uint64
-	x50, x51 = bits.Add64(x44, uint64(0x0), uint64(p224Uint1(x49)))
-	var x52 uint64
-	var x53 uint64
-	x52, x53 = bits.Add64(x46, uint64(0x0), uint64(p224Uint1(x51)))
-	var x54 uint64
-	_, x54 = bits.Mul64(x48, 0xffffffffffffffff)
-	var x56 uint64
-	var x57 uint64
-	x57, x56 = bits.Mul64(x54, 0xffffffff)
-	var x58 uint64
-	var x59 uint64
-	x59, x58 = bits.Mul64(x54, 0xffffffffffffffff)
-	var x60 uint64
-	var x61 uint64
-	x61, x60 = bits.Mul64(x54, 0xffffffff00000000)
-	var x62 uint64
-	var x63 uint64
-	x62, x63 = bits.Add64(x61, x58, uint64(0x0))
-	var x64 uint64
-	var x65 uint64
-	x64, x65 = bits.Add64(x59, x56, uint64(p224Uint1(x63)))
-	var x67 uint64
-	_, x67 = bits.Add64(x48, x54, uint64(0x0))
-	var x68 uint64
-	var x69 uint64
-	x68, x69 = bits.Add64(x50, x60, uint64(p224Uint1(x67)))
-	var x70 uint64
-	var x71 uint64
-	x70, x71 = bits.Add64(x52, x62, uint64(p224Uint1(x69)))
-	var x72 uint64
-	var x73 uint64
-	x72, x73 = bits.Add64((uint64(p224Uint1(x53)) + (uint64(p224Uint1(x47)) + (uint64(p224Uint1(x39)) + x31))), x64, uint64(p224Uint1(x71)))
-	var x74 uint64
-	var x75 uint64
-	x74, x75 = bits.Add64(x68, arg1[3], uint64(0x0))
-	var x76 uint64
-	var x77 uint64
-	x76, x77 = bits.Add64(x70, uint64(0x0), uint64(p224Uint1(x75)))
-	var x78 uint64
-	var x79 uint64
-	x78, x79 = bits.Add64(x72, uint64(0x0), uint64(p224Uint1(x77)))
-	var x80 uint64
-	_, x80 = bits.Mul64(x74, 0xffffffffffffffff)
-	var x82 uint64
-	var x83 uint64
-	x83, x82 = bits.Mul64(x80, 0xffffffff)
-	var x84 uint64
-	var x85 uint64
-	x85, x84 = bits.Mul64(x80, 0xffffffffffffffff)
-	var x86 uint64
-	var x87 uint64
-	x87, x86 = bits.Mul64(x80, 0xffffffff00000000)
-	var x88 uint64
-	var x89 uint64
-	x88, x89 = bits.Add64(x87, x84, uint64(0x0))
-	var x90 uint64
-	var x91 uint64
-	x90, x91 = bits.Add64(x85, x82, uint64(p224Uint1(x89)))
-	var x93 uint64
-	_, x93 = bits.Add64(x74, x80, uint64(0x0))
-	var x94 uint64
-	var x95 uint64
-	x94, x95 = bits.Add64(x76, x86, uint64(p224Uint1(x93)))
-	var x96 uint64
-	var x97 uint64
-	x96, x97 = bits.Add64(x78, x88, uint64(p224Uint1(x95)))
-	var x98 uint64
-	var x99 uint64
-	x98, x99 = bits.Add64((uint64(p224Uint1(x79)) + (uint64(p224Uint1(x73)) + (uint64(p224Uint1(x65)) + x57))), x90, uint64(p224Uint1(x97)))
-	x100 := (uint64(p224Uint1(x99)) + (uint64(p224Uint1(x91)) + x83))
-	var x101 uint64
-	var x102 uint64
-	x101, x102 = bits.Sub64(x94, uint64(0x1), uint64(0x0))
-	var x103 uint64
-	var x104 uint64
-	x103, x104 = bits.Sub64(x96, 0xffffffff00000000, uint64(p224Uint1(x102)))
-	var x105 uint64
-	var x106 uint64
-	x105, x106 = bits.Sub64(x98, 0xffffffffffffffff, uint64(p224Uint1(x104)))
-	var x107 uint64
-	var x108 uint64
-	x107, x108 = bits.Sub64(x100, 0xffffffff, uint64(p224Uint1(x106)))
-	var x110 uint64
-	_, x110 = bits.Sub64(uint64(0x0), uint64(0x0), uint64(p224Uint1(x108)))
-	var x111 uint64
-	p224CmovznzU64(&x111, p224Uint1(x110), x101, x94)
-	var x112 uint64
-	p224CmovznzU64(&x112, p224Uint1(x110), x103, x96)
-	var x113 uint64
-	p224CmovznzU64(&x113, p224Uint1(x110), x105, x98)
-	var x114 uint64
-	p224CmovznzU64(&x114, p224Uint1(x110), x107, x100)
-	out1[0] = x111
-	out1[1] = x112
-	out1[2] = x113
-	out1[3] = x114
-}
-
-// p224ToMontgomery translates a field element into the Montgomery domain.
-//
-// Preconditions:
-//   0 ≤ eval arg1 < m
-// Postconditions:
-//   eval (from_montgomery out1) mod m = eval arg1 mod m
-//   0 ≤ eval out1 < m
-//
-func p224ToMontgomery(out1 *p224MontgomeryDomainFieldElement, arg1 *p224NonMontgomeryDomainFieldElement) {
-	x1 := arg1[1]
-	x2 := arg1[2]
-	x3 := arg1[3]
-	x4 := arg1[0]
-	var x5 uint64
-	var x6 uint64
-	x6, x5 = bits.Mul64(x4, 0xffffffff)
-	var x7 uint64
-	var x8 uint64
-	x8, x7 = bits.Mul64(x4, 0xfffffffe00000000)
-	var x9 uint64
-	var x10 uint64
-	x10, x9 = bits.Mul64(x4, 0xffffffff00000000)
-	var x11 uint64
-	var x12 uint64
-	x12, x11 = bits.Mul64(x4, 0xffffffff00000001)
-	var x13 uint64
-	var x14 uint64
-	x13, x14 = bits.Add64(x12, x9, uint64(0x0))
-	var x15 uint64
-	var x16 uint64
-	x15, x16 = bits.Add64(x10, x7, uint64(p224Uint1(x14)))
-	var x17 uint64
-	var x18 uint64
-	x17, x18 = bits.Add64(x8, x5, uint64(p224Uint1(x16)))
-	var x19 uint64
-	_, x19 = bits.Mul64(x11, 0xffffffffffffffff)
-	var x21 uint64
-	var x22 uint64
-	x22, x21 = bits.Mul64(x19, 0xffffffff)
-	var x23 uint64
-	var x24 uint64
-	x24, x23 = bits.Mul64(x19, 0xffffffffffffffff)
-	var x25 uint64
-	var x26 uint64
-	x26, x25 = bits.Mul64(x19, 0xffffffff00000000)
-	var x27 uint64
-	var x28 uint64
-	x27, x28 = bits.Add64(x26, x23, uint64(0x0))
-	var x29 uint64
-	var x30 uint64
-	x29, x30 = bits.Add64(x24, x21, uint64(p224Uint1(x28)))
-	var x32 uint64
-	_, x32 = bits.Add64(x11, x19, uint64(0x0))
-	var x33 uint64
-	var x34 uint64
-	x33, x34 = bits.Add64(x13, x25, uint64(p224Uint1(x32)))
-	var x35 uint64
-	var x36 uint64
-	x35, x36 = bits.Add64(x15, x27, uint64(p224Uint1(x34)))
-	var x37 uint64
-	var x38 uint64
-	x37, x38 = bits.Add64(x17, x29, uint64(p224Uint1(x36)))
-	var x39 uint64
-	var x40 uint64
-	x40, x39 = bits.Mul64(x1, 0xffffffff)
-	var x41 uint64
-	var x42 uint64
-	x42, x41 = bits.Mul64(x1, 0xfffffffe00000000)
-	var x43 uint64
-	var x44 uint64
-	x44, x43 = bits.Mul64(x1, 0xffffffff00000000)
-	var x45 uint64
-	var x46 uint64
-	x46, x45 = bits.Mul64(x1, 0xffffffff00000001)
-	var x47 uint64
-	var x48 uint64
-	x47, x48 = bits.Add64(x46, x43, uint64(0x0))
-	var x49 uint64
-	var x50 uint64
-	x49, x50 = bits.Add64(x44, x41, uint64(p224Uint1(x48)))
-	var x51 uint64
-	var x52 uint64
-	x51, x52 = bits.Add64(x42, x39, uint64(p224Uint1(x50)))
-	var x53 uint64
-	var x54 uint64
-	x53, x54 = bits.Add64(x33, x45, uint64(0x0))
-	var x55 uint64
-	var x56 uint64
-	x55, x56 = bits.Add64(x35, x47, uint64(p224Uint1(x54)))
-	var x57 uint64
-	var x58 uint64
-	x57, x58 = bits.Add64(x37, x49, uint64(p224Uint1(x56)))
-	var x59 uint64
-	var x60 uint64
-	x59, x60 = bits.Add64(((uint64(p224Uint1(x38)) + (uint64(p224Uint1(x18)) + x6)) + (uint64(p224Uint1(x30)) + x22)), x51, uint64(p224Uint1(x58)))
-	var x61 uint64
-	_, x61 = bits.Mul64(x53, 0xffffffffffffffff)
-	var x63 uint64
-	var x64 uint64
-	x64, x63 = bits.Mul64(x61, 0xffffffff)
-	var x65 uint64
-	var x66 uint64
-	x66, x65 = bits.Mul64(x61, 0xffffffffffffffff)
-	var x67 uint64
-	var x68 uint64
-	x68, x67 = bits.Mul64(x61, 0xffffffff00000000)
-	var x69 uint64
-	var x70 uint64
-	x69, x70 = bits.Add64(x68, x65, uint64(0x0))
-	var x71 uint64
-	var x72 uint64
-	x71, x72 = bits.Add64(x66, x63, uint64(p224Uint1(x70)))
-	var x74 uint64
-	_, x74 = bits.Add64(x53, x61, uint64(0x0))
-	var x75 uint64
-	var x76 uint64
-	x75, x76 = bits.Add64(x55, x67, uint64(p224Uint1(x74)))
-	var x77 uint64
-	var x78 uint64
-	x77, x78 = bits.Add64(x57, x69, uint64(p224Uint1(x76)))
-	var x79 uint64
-	var x80 uint64
-	x79, x80 = bits.Add64(x59, x71, uint64(p224Uint1(x78)))
-	var x81 uint64
-	var x82 uint64
-	x82, x81 = bits.Mul64(x2, 0xffffffff)
-	var x83 uint64
-	var x84 uint64
-	x84, x83 = bits.Mul64(x2, 0xfffffffe00000000)
-	var x85 uint64
-	var x86 uint64
-	x86, x85 = bits.Mul64(x2, 0xffffffff00000000)
-	var x87 uint64
-	var x88 uint64
-	x88, x87 = bits.Mul64(x2, 0xffffffff00000001)
-	var x89 uint64
-	var x90 uint64
-	x89, x90 = bits.Add64(x88, x85, uint64(0x0))
-	var x91 uint64
-	var x92 uint64
-	x91, x92 = bits.Add64(x86, x83, uint64(p224Uint1(x90)))
-	var x93 uint64
-	var x94 uint64
-	x93, x94 = bits.Add64(x84, x81, uint64(p224Uint1(x92)))
-	var x95 uint64
-	var x96 uint64
-	x95, x96 = bits.Add64(x75, x87, uint64(0x0))
-	var x97 uint64
-	var x98 uint64
-	x97, x98 = bits.Add64(x77, x89, uint64(p224Uint1(x96)))
-	var x99 uint64
-	var x100 uint64
-	x99, x100 = bits.Add64(x79, x91, uint64(p224Uint1(x98)))
-	var x101 uint64
-	var x102 uint64
-	x101, x102 = bits.Add64(((uint64(p224Uint1(x80)) + (uint64(p224Uint1(x60)) + (uint64(p224Uint1(x52)) + x40))) + (uint64(p224Uint1(x72)) + x64)), x93, uint64(p224Uint1(x100)))
-	var x103 uint64
-	_, x103 = bits.Mul64(x95, 0xffffffffffffffff)
-	var x105 uint64
-	var x106 uint64
-	x106, x105 = bits.Mul64(x103, 0xffffffff)
-	var x107 uint64
-	var x108 uint64
-	x108, x107 = bits.Mul64(x103, 0xffffffffffffffff)
-	var x109 uint64
-	var x110 uint64
-	x110, x109 = bits.Mul64(x103, 0xffffffff00000000)
-	var x111 uint64
-	var x112 uint64
-	x111, x112 = bits.Add64(x110, x107, uint64(0x0))
-	var x113 uint64
-	var x114 uint64
-	x113, x114 = bits.Add64(x108, x105, uint64(p224Uint1(x112)))
-	var x116 uint64
-	_, x116 = bits.Add64(x95, x103, uint64(0x0))
-	var x117 uint64
-	var x118 uint64
-	x117, x118 = bits.Add64(x97, x109, uint64(p224Uint1(x116)))
-	var x119 uint64
-	var x120 uint64
-	x119, x120 = bits.Add64(x99, x111, uint64(p224Uint1(x118)))
-	var x121 uint64
-	var x122 uint64
-	x121, x122 = bits.Add64(x101, x113, uint64(p224Uint1(x120)))
-	var x123 uint64
-	var x124 uint64
-	x124, x123 = bits.Mul64(x3, 0xffffffff)
-	var x125 uint64
-	var x126 uint64
-	x126, x125 = bits.Mul64(x3, 0xfffffffe00000000)
-	var x127 uint64
-	var x128 uint64
-	x128, x127 = bits.Mul64(x3, 0xffffffff00000000)
-	var x129 uint64
-	var x130 uint64
-	x130, x129 = bits.Mul64(x3, 0xffffffff00000001)
-	var x131 uint64
-	var x132 uint64
-	x131, x132 = bits.Add64(x130, x127, uint64(0x0))
-	var x133 uint64
-	var x134 uint64
-	x133, x134 = bits.Add64(x128, x125, uint64(p224Uint1(x132)))
-	var x135 uint64
-	var x136 uint64
-	x135, x136 = bits.Add64(x126, x123, uint64(p224Uint1(x134)))
-	var x137 uint64
-	var x138 uint64
-	x137, x138 = bits.Add64(x117, x129, uint64(0x0))
-	var x139 uint64
-	var x140 uint64
-	x139, x140 = bits.Add64(x119, x131, uint64(p224Uint1(x138)))
-	var x141 uint64
-	var x142 uint64
-	x141, x142 = bits.Add64(x121, x133, uint64(p224Uint1(x140)))
-	var x143 uint64
-	var x144 uint64
-	x143, x144 = bits.Add64(((uint64(p224Uint1(x122)) + (uint64(p224Uint1(x102)) + (uint64(p224Uint1(x94)) + x82))) + (uint64(p224Uint1(x114)) + x106)), x135, uint64(p224Uint1(x142)))
-	var x145 uint64
-	_, x145 = bits.Mul64(x137, 0xffffffffffffffff)
-	var x147 uint64
-	var x148 uint64
-	x148, x147 = bits.Mul64(x145, 0xffffffff)
-	var x149 uint64
-	var x150 uint64
-	x150, x149 = bits.Mul64(x145, 0xffffffffffffffff)
-	var x151 uint64
-	var x152 uint64
-	x152, x151 = bits.Mul64(x145, 0xffffffff00000000)
-	var x153 uint64
-	var x154 uint64
-	x153, x154 = bits.Add64(x152, x149, uint64(0x0))
-	var x155 uint64
-	var x156 uint64
-	x155, x156 = bits.Add64(x150, x147, uint64(p224Uint1(x154)))
-	var x158 uint64
-	_, x158 = bits.Add64(x137, x145, uint64(0x0))
-	var x159 uint64
-	var x160 uint64
-	x159, x160 = bits.Add64(x139, x151, uint64(p224Uint1(x158)))
-	var x161 uint64
-	var x162 uint64
-	x161, x162 = bits.Add64(x141, x153, uint64(p224Uint1(x160)))
-	var x163 uint64
-	var x164 uint64
-	x163, x164 = bits.Add64(x143, x155, uint64(p224Uint1(x162)))
-	x165 := ((uint64(p224Uint1(x164)) + (uint64(p224Uint1(x144)) + (uint64(p224Uint1(x136)) + x124))) + (uint64(p224Uint1(x156)) + x148))
-	var x166 uint64
-	var x167 uint64
-	x166, x167 = bits.Sub64(x159, uint64(0x1), uint64(0x0))
-	var x168 uint64
-	var x169 uint64
-	x168, x169 = bits.Sub64(x161, 0xffffffff00000000, uint64(p224Uint1(x167)))
-	var x170 uint64
-	var x171 uint64
-	x170, x171 = bits.Sub64(x163, 0xffffffffffffffff, uint64(p224Uint1(x169)))
-	var x172 uint64
-	var x173 uint64
-	x172, x173 = bits.Sub64(x165, 0xffffffff, uint64(p224Uint1(x171)))
-	var x175 uint64
-	_, x175 = bits.Sub64(uint64(0x0), uint64(0x0), uint64(p224Uint1(x173)))
-	var x176 uint64
-	p224CmovznzU64(&x176, p224Uint1(x175), x166, x159)
-	var x177 uint64
-	p224CmovznzU64(&x177, p224Uint1(x175), x168, x161)
-	var x178 uint64
-	p224CmovznzU64(&x178, p224Uint1(x175), x170, x163)
-	var x179 uint64
-	p224CmovznzU64(&x179, p224Uint1(x175), x172, x165)
-	out1[0] = x176
-	out1[1] = x177
-	out1[2] = x178
-	out1[3] = x179
-}
-
-// p224Selectznz is a multi-limb conditional select.
-//
-// Postconditions:
-//   eval out1 = (if arg1 = 0 then eval arg2 else eval arg3)
-//
-// Input Bounds:
-//   arg1: [0x0 ~> 0x1]
-//   arg2: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
-//   arg3: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
-// Output Bounds:
-//   out1: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
-func p224Selectznz(out1 *[4]uint64, arg1 p224Uint1, arg2 *[4]uint64, arg3 *[4]uint64) {
-	var x1 uint64
-	p224CmovznzU64(&x1, arg1, arg2[0], arg3[0])
-	var x2 uint64
-	p224CmovznzU64(&x2, arg1, arg2[1], arg3[1])
-	var x3 uint64
-	p224CmovznzU64(&x3, arg1, arg2[2], arg3[2])
-	var x4 uint64
-	p224CmovznzU64(&x4, arg1, arg2[3], arg3[3])
-	out1[0] = x1
-	out1[1] = x2
-	out1[2] = x3
-	out1[3] = x4
-}
-
-// p224ToBytes serializes a field element NOT in the Montgomery domain to bytes in little-endian order.
-//
-// Preconditions:
-//   0 ≤ eval arg1 < m
-// Postconditions:
-//   out1 = map (λ x, ⌊((eval arg1 mod m) mod 2^(8 * (x + 1))) / 2^(8 * x)⌋) [0..27]
-//
-// Input Bounds:
-//   arg1: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffff]]
-// Output Bounds:
-//   out1: [[0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff]]
-func p224ToBytes(out1 *[28]uint8, arg1 *[4]uint64) {
-	x1 := arg1[3]
-	x2 := arg1[2]
-	x3 := arg1[1]
-	x4 := arg1[0]
-	x5 := (uint8(x4) & 0xff)
-	x6 := (x4 >> 8)
-	x7 := (uint8(x6) & 0xff)
-	x8 := (x6 >> 8)
-	x9 := (uint8(x8) & 0xff)
-	x10 := (x8 >> 8)
-	x11 := (uint8(x10) & 0xff)
-	x12 := (x10 >> 8)
-	x13 := (uint8(x12) & 0xff)
-	x14 := (x12 >> 8)
-	x15 := (uint8(x14) & 0xff)
-	x16 := (x14 >> 8)
-	x17 := (uint8(x16) & 0xff)
-	x18 := uint8((x16 >> 8))
-	x19 := (uint8(x3) & 0xff)
-	x20 := (x3 >> 8)
-	x21 := (uint8(x20) & 0xff)
-	x22 := (x20 >> 8)
-	x23 := (uint8(x22) & 0xff)
-	x24 := (x22 >> 8)
-	x25 := (uint8(x24) & 0xff)
-	x26 := (x24 >> 8)
-	x27 := (uint8(x26) & 0xff)
-	x28 := (x26 >> 8)
-	x29 := (uint8(x28) & 0xff)
-	x30 := (x28 >> 8)
-	x31 := (uint8(x30) & 0xff)
-	x32 := uint8((x30 >> 8))
-	x33 := (uint8(x2) & 0xff)
-	x34 := (x2 >> 8)
-	x35 := (uint8(x34) & 0xff)
-	x36 := (x34 >> 8)
-	x37 := (uint8(x36) & 0xff)
-	x38 := (x36 >> 8)
-	x39 := (uint8(x38) & 0xff)
-	x40 := (x38 >> 8)
-	x41 := (uint8(x40) & 0xff)
-	x42 := (x40 >> 8)
-	x43 := (uint8(x42) & 0xff)
-	x44 := (x42 >> 8)
-	x45 := (uint8(x44) & 0xff)
-	x46 := uint8((x44 >> 8))
-	x47 := (uint8(x1) & 0xff)
-	x48 := (x1 >> 8)
-	x49 := (uint8(x48) & 0xff)
-	x50 := (x48 >> 8)
-	x51 := (uint8(x50) & 0xff)
-	x52 := uint8((x50 >> 8))
-	out1[0] = x5
-	out1[1] = x7
-	out1[2] = x9
-	out1[3] = x11
-	out1[4] = x13
-	out1[5] = x15
-	out1[6] = x17
-	out1[7] = x18
-	out1[8] = x19
-	out1[9] = x21
-	out1[10] = x23
-	out1[11] = x25
-	out1[12] = x27
-	out1[13] = x29
-	out1[14] = x31
-	out1[15] = x32
-	out1[16] = x33
-	out1[17] = x35
-	out1[18] = x37
-	out1[19] = x39
-	out1[20] = x41
-	out1[21] = x43
-	out1[22] = x45
-	out1[23] = x46
-	out1[24] = x47
-	out1[25] = x49
-	out1[26] = x51
-	out1[27] = x52
-}
-
-// p224FromBytes deserializes a field element NOT in the Montgomery domain from bytes in little-endian order.
-//
-// Preconditions:
-//   0 ≤ bytes_eval arg1 < m
-// Postconditions:
-//   eval out1 mod m = bytes_eval arg1 mod m
-//   0 ≤ eval out1 < m
-//
-// Input Bounds:
-//   arg1: [[0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff]]
-// Output Bounds:
-//   out1: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffff]]
-func p224FromBytes(out1 *[4]uint64, arg1 *[28]uint8) {
-	x1 := (uint64(arg1[27]) << 24)
-	x2 := (uint64(arg1[26]) << 16)
-	x3 := (uint64(arg1[25]) << 8)
-	x4 := arg1[24]
-	x5 := (uint64(arg1[23]) << 56)
-	x6 := (uint64(arg1[22]) << 48)
-	x7 := (uint64(arg1[21]) << 40)
-	x8 := (uint64(arg1[20]) << 32)
-	x9 := (uint64(arg1[19]) << 24)
-	x10 := (uint64(arg1[18]) << 16)
-	x11 := (uint64(arg1[17]) << 8)
-	x12 := arg1[16]
-	x13 := (uint64(arg1[15]) << 56)
-	x14 := (uint64(arg1[14]) << 48)
-	x15 := (uint64(arg1[13]) << 40)
-	x16 := (uint64(arg1[12]) << 32)
-	x17 := (uint64(arg1[11]) << 24)
-	x18 := (uint64(arg1[10]) << 16)
-	x19 := (uint64(arg1[9]) << 8)
-	x20 := arg1[8]
-	x21 := (uint64(arg1[7]) << 56)
-	x22 := (uint64(arg1[6]) << 48)
-	x23 := (uint64(arg1[5]) << 40)
-	x24 := (uint64(arg1[4]) << 32)
-	x25 := (uint64(arg1[3]) << 24)
-	x26 := (uint64(arg1[2]) << 16)
-	x27 := (uint64(arg1[1]) << 8)
-	x28 := arg1[0]
-	x29 := (x27 + uint64(x28))
-	x30 := (x26 + x29)
-	x31 := (x25 + x30)
-	x32 := (x24 + x31)
-	x33 := (x23 + x32)
-	x34 := (x22 + x33)
-	x35 := (x21 + x34)
-	x36 := (x19 + uint64(x20))
-	x37 := (x18 + x36)
-	x38 := (x17 + x37)
-	x39 := (x16 + x38)
-	x40 := (x15 + x39)
-	x41 := (x14 + x40)
-	x42 := (x13 + x41)
-	x43 := (x11 + uint64(x12))
-	x44 := (x10 + x43)
-	x45 := (x9 + x44)
-	x46 := (x8 + x45)
-	x47 := (x7 + x46)
-	x48 := (x6 + x47)
-	x49 := (x5 + x48)
-	x50 := (x3 + uint64(x4))
-	x51 := (x2 + x50)
-	x52 := (x1 + x51)
-	out1[0] = x35
-	out1[1] = x42
-	out1[2] = x49
-	out1[3] = x52
-}
diff --git a/contrib/go/_std_1.18/src/crypto/elliptic/internal/fiat/p384_fiat64.go b/contrib/go/_std_1.18/src/crypto/elliptic/internal/fiat/p384_fiat64.go
deleted file mode 100644
index 493bed47e1..0000000000
--- a/contrib/go/_std_1.18/src/crypto/elliptic/internal/fiat/p384_fiat64.go
+++ /dev/null
@@ -1,3004 +0,0 @@
-// Code generated by Fiat Cryptography. DO NOT EDIT.
-//
-// Autogenerated: word_by_word_montgomery --lang Go --no-wide-int --cmovznz-by-mul --relax-primitive-carry-to-bitwidth 32,64 --internal-static --public-function-case camelCase --public-type-case camelCase --private-function-case camelCase --private-type-case camelCase --doc-text-before-function-name '' --doc-newline-before-package-declaration --doc-prepend-header 'Code generated by Fiat Cryptography. DO NOT EDIT.' --package-name fiat --no-prefix-fiat p384 64 '2^384 - 2^128 - 2^96 + 2^32 - 1' mul square add sub one from_montgomery to_montgomery selectznz to_bytes from_bytes
-//
-// curve description: p384
-//
-// machine_wordsize = 64 (from "64")
-//
-// requested operations: mul, square, add, sub, one, from_montgomery, to_montgomery, selectznz, to_bytes, from_bytes
-//
-// m = 0xfffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffeffffffff0000000000000000ffffffff (from "2^384 - 2^128 - 2^96 + 2^32 - 1")
-//
-//
-//
-// NOTE: In addition to the bounds specified above each function, all
-//
-//   functions synthesized for this Montgomery arithmetic require the
-//
-//   input to be strictly less than the prime modulus (m), and also
-//
-//   require the input to be in the unique saturated representation.
-//
-//   All functions also ensure that these two properties are true of
-//
-//   return values.
-//
-//
-//
-// Computed values:
-//
-//   eval z = z[0] + (z[1] << 64) + (z[2] << 128) + (z[3] << 192) + (z[4] << 256) + (z[5] << 0x140)
-//
-//   bytes_eval z = z[0] + (z[1] << 8) + (z[2] << 16) + (z[3] << 24) + (z[4] << 32) + (z[5] << 40) + (z[6] << 48) + (z[7] << 56) + (z[8] << 64) + (z[9] << 72) + (z[10] << 80) + (z[11] << 88) + (z[12] << 96) + (z[13] << 104) + (z[14] << 112) + (z[15] << 120) + (z[16] << 128) + (z[17] << 136) + (z[18] << 144) + (z[19] << 152) + (z[20] << 160) + (z[21] << 168) + (z[22] << 176) + (z[23] << 184) + (z[24] << 192) + (z[25] << 200) + (z[26] << 208) + (z[27] << 216) + (z[28] << 224) + (z[29] << 232) + (z[30] << 240) + (z[31] << 248) + (z[32] << 256) + (z[33] << 0x108) + (z[34] << 0x110) + (z[35] << 0x118) + (z[36] << 0x120) + (z[37] << 0x128) + (z[38] << 0x130) + (z[39] << 0x138) + (z[40] << 0x140) + (z[41] << 0x148) + (z[42] << 0x150) + (z[43] << 0x158) + (z[44] << 0x160) + (z[45] << 0x168) + (z[46] << 0x170) + (z[47] << 0x178)
-//
-//   twos_complement_eval z = let x1 := z[0] + (z[1] << 64) + (z[2] << 128) + (z[3] << 192) + (z[4] << 256) + (z[5] << 0x140) in
-//
-//                            if x1 & (2^384-1) < 2^383 then x1 & (2^384-1) else (x1 & (2^384-1)) - 2^384
-
-package fiat
-
-import "math/bits"
-
-type p384Uint1 uint64 // We use uint64 instead of a more narrow type for performance reasons; see https://github.com/mit-plv/fiat-crypto/pull/1006#issuecomment-892625927
-type p384Int1 int64   // We use uint64 instead of a more narrow type for performance reasons; see https://github.com/mit-plv/fiat-crypto/pull/1006#issuecomment-892625927
-
-// The type p384MontgomeryDomainFieldElement is a field element in the Montgomery domain.
-//
-// Bounds: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
-type p384MontgomeryDomainFieldElement [6]uint64
-
-// The type p384NonMontgomeryDomainFieldElement is a field element NOT in the Montgomery domain.
-//
-// Bounds: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
-type p384NonMontgomeryDomainFieldElement [6]uint64
-
-// p384CmovznzU64 is a single-word conditional move.
-//
-// Postconditions:
-//   out1 = (if arg1 = 0 then arg2 else arg3)
-//
-// Input Bounds:
-//   arg1: [0x0 ~> 0x1]
-//   arg2: [0x0 ~> 0xffffffffffffffff]
-//   arg3: [0x0 ~> 0xffffffffffffffff]
-// Output Bounds:
-//   out1: [0x0 ~> 0xffffffffffffffff]
-func p384CmovznzU64(out1 *uint64, arg1 p384Uint1, arg2 uint64, arg3 uint64) {
-	x1 := (uint64(arg1) * 0xffffffffffffffff)
-	x2 := ((x1 & arg3) | ((^x1) & arg2))
-	*out1 = x2
-}
-
-// p384Mul multiplies two field elements in the Montgomery domain.
-//
-// Preconditions:
-//   0 ≤ eval arg1 < m
-//   0 ≤ eval arg2 < m
-// Postconditions:
-//   eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) * eval (from_montgomery arg2)) mod m
-//   0 ≤ eval out1 < m
-//
-func p384Mul(out1 *p384MontgomeryDomainFieldElement, arg1 *p384MontgomeryDomainFieldElement, arg2 *p384MontgomeryDomainFieldElement) {
-	x1 := arg1[1]
-	x2 := arg1[2]
-	x3 := arg1[3]
-	x4 := arg1[4]
-	x5 := arg1[5]
-	x6 := arg1[0]
-	var x7 uint64
-	var x8 uint64
-	x8, x7 = bits.Mul64(x6, arg2[5])
-	var x9 uint64
-	var x10 uint64
-	x10, x9 = bits.Mul64(x6, arg2[4])
-	var x11 uint64
-	var x12 uint64
-	x12, x11 = bits.Mul64(x6, arg2[3])
-	var x13 uint64
-	var x14 uint64
-	x14, x13 = bits.Mul64(x6, arg2[2])
-	var x15 uint64
-	var x16 uint64
-	x16, x15 = bits.Mul64(x6, arg2[1])
-	var x17 uint64
-	var x18 uint64
-	x18, x17 = bits.Mul64(x6, arg2[0])
-	var x19 uint64
-	var x20 uint64
-	x19, x20 = bits.Add64(x18, x15, uint64(0x0))
-	var x21 uint64
-	var x22 uint64
-	x21, x22 = bits.Add64(x16, x13, uint64(p384Uint1(x20)))
-	var x23 uint64
-	var x24 uint64
-	x23, x24 = bits.Add64(x14, x11, uint64(p384Uint1(x22)))
-	var x25 uint64
-	var x26 uint64
-	x25, x26 = bits.Add64(x12, x9, uint64(p384Uint1(x24)))
-	var x27 uint64
-	var x28 uint64
-	x27, x28 = bits.Add64(x10, x7, uint64(p384Uint1(x26)))
-	x29 := (uint64(p384Uint1(x28)) + x8)
-	var x30 uint64
-	_, x30 = bits.Mul64(x17, 0x100000001)
-	var x32 uint64
-	var x33 uint64
-	x33, x32 = bits.Mul64(x30, 0xffffffffffffffff)
-	var x34 uint64
-	var x35 uint64
-	x35, x34 = bits.Mul64(x30, 0xffffffffffffffff)
-	var x36 uint64
-	var x37 uint64
-	x37, x36 = bits.Mul64(x30, 0xffffffffffffffff)
-	var x38 uint64
-	var x39 uint64
-	x39, x38 = bits.Mul64(x30, 0xfffffffffffffffe)
-	var x40 uint64
-	var x41 uint64
-	x41, x40 = bits.Mul64(x30, 0xffffffff00000000)
-	var x42 uint64
-	var x43 uint64
-	x43, x42 = bits.Mul64(x30, 0xffffffff)
-	var x44 uint64
-	var x45 uint64
-	x44, x45 = bits.Add64(x43, x40, uint64(0x0))
-	var x46 uint64
-	var x47 uint64
-	x46, x47 = bits.Add64(x41, x38, uint64(p384Uint1(x45)))
-	var x48 uint64
-	var x49 uint64
-	x48, x49 = bits.Add64(x39, x36, uint64(p384Uint1(x47)))
-	var x50 uint64
-	var x51 uint64
-	x50, x51 = bits.Add64(x37, x34, uint64(p384Uint1(x49)))
-	var x52 uint64
-	var x53 uint64
-	x52, x53 = bits.Add64(x35, x32, uint64(p384Uint1(x51)))
-	x54 := (uint64(p384Uint1(x53)) + x33)
-	var x56 uint64
-	_, x56 = bits.Add64(x17, x42, uint64(0x0))
-	var x57 uint64
-	var x58 uint64
-	x57, x58 = bits.Add64(x19, x44, uint64(p384Uint1(x56)))
-	var x59 uint64
-	var x60 uint64
-	x59, x60 = bits.Add64(x21, x46, uint64(p384Uint1(x58)))
-	var x61 uint64
-	var x62 uint64
-	x61, x62 = bits.Add64(x23, x48, uint64(p384Uint1(x60)))
-	var x63 uint64
-	var x64 uint64
-	x63, x64 = bits.Add64(x25, x50, uint64(p384Uint1(x62)))
-	var x65 uint64
-	var x66 uint64
-	x65, x66 = bits.Add64(x27, x52, uint64(p384Uint1(x64)))
-	var x67 uint64
-	var x68 uint64
-	x67, x68 = bits.Add64(x29, x54, uint64(p384Uint1(x66)))
-	var x69 uint64
-	var x70 uint64
-	x70, x69 = bits.Mul64(x1, arg2[5])
-	var x71 uint64
-	var x72 uint64
-	x72, x71 = bits.Mul64(x1, arg2[4])
-	var x73 uint64
-	var x74 uint64
-	x74, x73 = bits.Mul64(x1, arg2[3])
-	var x75 uint64
-	var x76 uint64
-	x76, x75 = bits.Mul64(x1, arg2[2])
-	var x77 uint64
-	var x78 uint64
-	x78, x77 = bits.Mul64(x1, arg2[1])
-	var x79 uint64
-	var x80 uint64
-	x80, x79 = bits.Mul64(x1, arg2[0])
-	var x81 uint64
-	var x82 uint64
-	x81, x82 = bits.Add64(x80, x77, uint64(0x0))
-	var x83 uint64
-	var x84 uint64
-	x83, x84 = bits.Add64(x78, x75, uint64(p384Uint1(x82)))
-	var x85 uint64
-	var x86 uint64
-	x85, x86 = bits.Add64(x76, x73, uint64(p384Uint1(x84)))
-	var x87 uint64
-	var x88 uint64
-	x87, x88 = bits.Add64(x74, x71, uint64(p384Uint1(x86)))
-	var x89 uint64
-	var x90 uint64
-	x89, x90 = bits.Add64(x72, x69, uint64(p384Uint1(x88)))
-	x91 := (uint64(p384Uint1(x90)) + x70)
-	var x92 uint64
-	var x93 uint64
-	x92, x93 = bits.Add64(x57, x79, uint64(0x0))
-	var x94 uint64
-	var x95 uint64
-	x94, x95 = bits.Add64(x59, x81, uint64(p384Uint1(x93)))
-	var x96 uint64
-	var x97 uint64
-	x96, x97 = bits.Add64(x61, x83, uint64(p384Uint1(x95)))
-	var x98 uint64
-	var x99 uint64
-	x98, x99 = bits.Add64(x63, x85, uint64(p384Uint1(x97)))
-	var x100 uint64
-	var x101 uint64
-	x100, x101 = bits.Add64(x65, x87, uint64(p384Uint1(x99)))
-	var x102 uint64
-	var x103 uint64
-	x102, x103 = bits.Add64(x67, x89, uint64(p384Uint1(x101)))
-	var x104 uint64
-	var x105 uint64
-	x104, x105 = bits.Add64(uint64(p384Uint1(x68)), x91, uint64(p384Uint1(x103)))
-	var x106 uint64
-	_, x106 = bits.Mul64(x92, 0x100000001)
-	var x108 uint64
-	var x109 uint64
-	x109, x108 = bits.Mul64(x106, 0xffffffffffffffff)
-	var x110 uint64
-	var x111 uint64
-	x111, x110 = bits.Mul64(x106, 0xffffffffffffffff)
-	var x112 uint64
-	var x113 uint64
-	x113, x112 = bits.Mul64(x106, 0xffffffffffffffff)
-	var x114 uint64
-	var x115 uint64
-	x115, x114 = bits.Mul64(x106, 0xfffffffffffffffe)
-	var x116 uint64
-	var x117 uint64
-	x117, x116 = bits.Mul64(x106, 0xffffffff00000000)
-	var x118 uint64
-	var x119 uint64
-	x119, x118 = bits.Mul64(x106, 0xffffffff)
-	var x120 uint64
-	var x121 uint64
-	x120, x121 = bits.Add64(x119, x116, uint64(0x0))
-	var x122 uint64
-	var x123 uint64
-	x122, x123 = bits.Add64(x117, x114, uint64(p384Uint1(x121)))
-	var x124 uint64
-	var x125 uint64
-	x124, x125 = bits.Add64(x115, x112, uint64(p384Uint1(x123)))
-	var x126 uint64
-	var x127 uint64
-	x126, x127 = bits.Add64(x113, x110, uint64(p384Uint1(x125)))
-	var x128 uint64
-	var x129 uint64
-	x128, x129 = bits.Add64(x111, x108, uint64(p384Uint1(x127)))
-	x130 := (uint64(p384Uint1(x129)) + x109)
-	var x132 uint64
-	_, x132 = bits.Add64(x92, x118, uint64(0x0))
-	var x133 uint64
-	var x134 uint64
-	x133, x134 = bits.Add64(x94, x120, uint64(p384Uint1(x132)))
-	var x135 uint64
-	var x136 uint64
-	x135, x136 = bits.Add64(x96, x122, uint64(p384Uint1(x134)))
-	var x137 uint64
-	var x138 uint64
-	x137, x138 = bits.Add64(x98, x124, uint64(p384Uint1(x136)))
-	var x139 uint64
-	var x140 uint64
-	x139, x140 = bits.Add64(x100, x126, uint64(p384Uint1(x138)))
-	var x141 uint64
-	var x142 uint64
-	x141, x142 = bits.Add64(x102, x128, uint64(p384Uint1(x140)))
-	var x143 uint64
-	var x144 uint64
-	x143, x144 = bits.Add64(x104, x130, uint64(p384Uint1(x142)))
-	x145 := (uint64(p384Uint1(x144)) + uint64(p384Uint1(x105)))
-	var x146 uint64
-	var x147 uint64
-	x147, x146 = bits.Mul64(x2, arg2[5])
-	var x148 uint64
-	var x149 uint64
-	x149, x148 = bits.Mul64(x2, arg2[4])
-	var x150 uint64
-	var x151 uint64
-	x151, x150 = bits.Mul64(x2, arg2[3])
-	var x152 uint64
-	var x153 uint64
-	x153, x152 = bits.Mul64(x2, arg2[2])
-	var x154 uint64
-	var x155 uint64
-	x155, x154 = bits.Mul64(x2, arg2[1])
-	var x156 uint64
-	var x157 uint64
-	x157, x156 = bits.Mul64(x2, arg2[0])
-	var x158 uint64
-	var x159 uint64
-	x158, x159 = bits.Add64(x157, x154, uint64(0x0))
-	var x160 uint64
-	var x161 uint64
-	x160, x161 = bits.Add64(x155, x152, uint64(p384Uint1(x159)))
-	var x162 uint64
-	var x163 uint64
-	x162, x163 = bits.Add64(x153, x150, uint64(p384Uint1(x161)))
-	var x164 uint64
-	var x165 uint64
-	x164, x165 = bits.Add64(x151, x148, uint64(p384Uint1(x163)))
-	var x166 uint64
-	var x167 uint64
-	x166, x167 = bits.Add64(x149, x146, uint64(p384Uint1(x165)))
-	x168 := (uint64(p384Uint1(x167)) + x147)
-	var x169 uint64
-	var x170 uint64
-	x169, x170 = bits.Add64(x133, x156, uint64(0x0))
-	var x171 uint64
-	var x172 uint64
-	x171, x172 = bits.Add64(x135, x158, uint64(p384Uint1(x170)))
-	var x173 uint64
-	var x174 uint64
-	x173, x174 = bits.Add64(x137, x160, uint64(p384Uint1(x172)))
-	var x175 uint64
-	var x176 uint64
-	x175, x176 = bits.Add64(x139, x162, uint64(p384Uint1(x174)))
-	var x177 uint64
-	var x178 uint64
-	x177, x178 = bits.Add64(x141, x164, uint64(p384Uint1(x176)))
-	var x179 uint64
-	var x180 uint64
-	x179, x180 = bits.Add64(x143, x166, uint64(p384Uint1(x178)))
-	var x181 uint64
-	var x182 uint64
-	x181, x182 = bits.Add64(x145, x168, uint64(p384Uint1(x180)))
-	var x183 uint64
-	_, x183 = bits.Mul64(x169, 0x100000001)
-	var x185 uint64
-	var x186 uint64
-	x186, x185 = bits.Mul64(x183, 0xffffffffffffffff)
-	var x187 uint64
-	var x188 uint64
-	x188, x187 = bits.Mul64(x183, 0xffffffffffffffff)
-	var x189 uint64
-	var x190 uint64
-	x190, x189 = bits.Mul64(x183, 0xffffffffffffffff)
-	var x191 uint64
-	var x192 uint64
-	x192, x191 = bits.Mul64(x183, 0xfffffffffffffffe)
-	var x193 uint64
-	var x194 uint64
-	x194, x193 = bits.Mul64(x183, 0xffffffff00000000)
-	var x195 uint64
-	var x196 uint64
-	x196, x195 = bits.Mul64(x183, 0xffffffff)
-	var x197 uint64
-	var x198 uint64
-	x197, x198 = bits.Add64(x196, x193, uint64(0x0))
-	var x199 uint64
-	var x200 uint64
-	x199, x200 = bits.Add64(x194, x191, uint64(p384Uint1(x198)))
-	var x201 uint64
-	var x202 uint64
-	x201, x202 = bits.Add64(x192, x189, uint64(p384Uint1(x200)))
-	var x203 uint64
-	var x204 uint64
-	x203, x204 = bits.Add64(x190, x187, uint64(p384Uint1(x202)))
-	var x205 uint64
-	var x206 uint64
-	x205, x206 = bits.Add64(x188, x185, uint64(p384Uint1(x204)))
-	x207 := (uint64(p384Uint1(x206)) + x186)
-	var x209 uint64
-	_, x209 = bits.Add64(x169, x195, uint64(0x0))
-	var x210 uint64
-	var x211 uint64
-	x210, x211 = bits.Add64(x171, x197, uint64(p384Uint1(x209)))
-	var x212 uint64
-	var x213 uint64
-	x212, x213 = bits.Add64(x173, x199, uint64(p384Uint1(x211)))
-	var x214 uint64
-	var x215 uint64
-	x214, x215 = bits.Add64(x175, x201, uint64(p384Uint1(x213)))
-	var x216 uint64
-	var x217 uint64
-	x216, x217 = bits.Add64(x177, x203, uint64(p384Uint1(x215)))
-	var x218 uint64
-	var x219 uint64
-	x218, x219 = bits.Add64(x179, x205, uint64(p384Uint1(x217)))
-	var x220 uint64
-	var x221 uint64
-	x220, x221 = bits.Add64(x181, x207, uint64(p384Uint1(x219)))
-	x222 := (uint64(p384Uint1(x221)) + uint64(p384Uint1(x182)))
-	var x223 uint64
-	var x224 uint64
-	x224, x223 = bits.Mul64(x3, arg2[5])
-	var x225 uint64
-	var x226 uint64
-	x226, x225 = bits.Mul64(x3, arg2[4])
-	var x227 uint64
-	var x228 uint64
-	x228, x227 = bits.Mul64(x3, arg2[3])
-	var x229 uint64
-	var x230 uint64
-	x230, x229 = bits.Mul64(x3, arg2[2])
-	var x231 uint64
-	var x232 uint64
-	x232, x231 = bits.Mul64(x3, arg2[1])
-	var x233 uint64
-	var x234 uint64
-	x234, x233 = bits.Mul64(x3, arg2[0])
-	var x235 uint64
-	var x236 uint64
-	x235, x236 = bits.Add64(x234, x231, uint64(0x0))
-	var x237 uint64
-	var x238 uint64
-	x237, x238 = bits.Add64(x232, x229, uint64(p384Uint1(x236)))
-	var x239 uint64
-	var x240 uint64
-	x239, x240 = bits.Add64(x230, x227, uint64(p384Uint1(x238)))
-	var x241 uint64
-	var x242 uint64
-	x241, x242 = bits.Add64(x228, x225, uint64(p384Uint1(x240)))
-	var x243 uint64
-	var x244 uint64
-	x243, x244 = bits.Add64(x226, x223, uint64(p384Uint1(x242)))
-	x245 := (uint64(p384Uint1(x244)) + x224)
-	var x246 uint64
-	var x247 uint64
-	x246, x247 = bits.Add64(x210, x233, uint64(0x0))
-	var x248 uint64
-	var x249 uint64
-	x248, x249 = bits.Add64(x212, x235, uint64(p384Uint1(x247)))
-	var x250 uint64
-	var x251 uint64
-	x250, x251 = bits.Add64(x214, x237, uint64(p384Uint1(x249)))
-	var x252 uint64
-	var x253 uint64
-	x252, x253 = bits.Add64(x216, x239, uint64(p384Uint1(x251)))
-	var x254 uint64
-	var x255 uint64
-	x254, x255 = bits.Add64(x218, x241, uint64(p384Uint1(x253)))
-	var x256 uint64
-	var x257 uint64
-	x256, x257 = bits.Add64(x220, x243, uint64(p384Uint1(x255)))
-	var x258 uint64
-	var x259 uint64
-	x258, x259 = bits.Add64(x222, x245, uint64(p384Uint1(x257)))
-	var x260 uint64
-	_, x260 = bits.Mul64(x246, 0x100000001)
-	var x262 uint64
-	var x263 uint64
-	x263, x262 = bits.Mul64(x260, 0xffffffffffffffff)
-	var x264 uint64
-	var x265 uint64
-	x265, x264 = bits.Mul64(x260, 0xffffffffffffffff)
-	var x266 uint64
-	var x267 uint64
-	x267, x266 = bits.Mul64(x260, 0xffffffffffffffff)
-	var x268 uint64
-	var x269 uint64
-	x269, x268 = bits.Mul64(x260, 0xfffffffffffffffe)
-	var x270 uint64
-	var x271 uint64
-	x271, x270 = bits.Mul64(x260, 0xffffffff00000000)
-	var x272 uint64
-	var x273 uint64
-	x273, x272 = bits.Mul64(x260, 0xffffffff)
-	var x274 uint64
-	var x275 uint64
-	x274, x275 = bits.Add64(x273, x270, uint64(0x0))
-	var x276 uint64
-	var x277 uint64
-	x276, x277 = bits.Add64(x271, x268, uint64(p384Uint1(x275)))
-	var x278 uint64
-	var x279 uint64
-	x278, x279 = bits.Add64(x269, x266, uint64(p384Uint1(x277)))
-	var x280 uint64
-	var x281 uint64
-	x280, x281 = bits.Add64(x267, x264, uint64(p384Uint1(x279)))
-	var x282 uint64
-	var x283 uint64
-	x282, x283 = bits.Add64(x265, x262, uint64(p384Uint1(x281)))
-	x284 := (uint64(p384Uint1(x283)) + x263)
-	var x286 uint64
-	_, x286 = bits.Add64(x246, x272, uint64(0x0))
-	var x287 uint64
-	var x288 uint64
-	x287, x288 = bits.Add64(x248, x274, uint64(p384Uint1(x286)))
-	var x289 uint64
-	var x290 uint64
-	x289, x290 = bits.Add64(x250, x276, uint64(p384Uint1(x288)))
-	var x291 uint64
-	var x292 uint64
-	x291, x292 = bits.Add64(x252, x278, uint64(p384Uint1(x290)))
-	var x293 uint64
-	var x294 uint64
-	x293, x294 = bits.Add64(x254, x280, uint64(p384Uint1(x292)))
-	var x295 uint64
-	var x296 uint64
-	x295, x296 = bits.Add64(x256, x282, uint64(p384Uint1(x294)))
-	var x297 uint64
-	var x298 uint64
-	x297, x298 = bits.Add64(x258, x284, uint64(p384Uint1(x296)))
-	x299 := (uint64(p384Uint1(x298)) + uint64(p384Uint1(x259)))
-	var x300 uint64
-	var x301 uint64
-	x301, x300 = bits.Mul64(x4, arg2[5])
-	var x302 uint64
-	var x303 uint64
-	x303, x302 = bits.Mul64(x4, arg2[4])
-	var x304 uint64
-	var x305 uint64
-	x305, x304 = bits.Mul64(x4, arg2[3])
-	var x306 uint64
-	var x307 uint64
-	x307, x306 = bits.Mul64(x4, arg2[2])
-	var x308 uint64
-	var x309 uint64
-	x309, x308 = bits.Mul64(x4, arg2[1])
-	var x310 uint64
-	var x311 uint64
-	x311, x310 = bits.Mul64(x4, arg2[0])
-	var x312 uint64
-	var x313 uint64
-	x312, x313 = bits.Add64(x311, x308, uint64(0x0))
-	var x314 uint64
-	var x315 uint64
-	x314, x315 = bits.Add64(x309, x306, uint64(p384Uint1(x313)))
-	var x316 uint64
-	var x317 uint64
-	x316, x317 = bits.Add64(x307, x304, uint64(p384Uint1(x315)))
-	var x318 uint64
-	var x319 uint64
-	x318, x319 = bits.Add64(x305, x302, uint64(p384Uint1(x317)))
-	var x320 uint64
-	var x321 uint64
-	x320, x321 = bits.Add64(x303, x300, uint64(p384Uint1(x319)))
-	x322 := (uint64(p384Uint1(x321)) + x301)
-	var x323 uint64
-	var x324 uint64
-	x323, x324 = bits.Add64(x287, x310, uint64(0x0))
-	var x325 uint64
-	var x326 uint64
-	x325, x326 = bits.Add64(x289, x312, uint64(p384Uint1(x324)))
-	var x327 uint64
-	var x328 uint64
-	x327, x328 = bits.Add64(x291, x314, uint64(p384Uint1(x326)))
-	var x329 uint64
-	var x330 uint64
-	x329, x330 = bits.Add64(x293, x316, uint64(p384Uint1(x328)))
-	var x331 uint64
-	var x332 uint64
-	x331, x332 = bits.Add64(x295, x318, uint64(p384Uint1(x330)))
-	var x333 uint64
-	var x334 uint64
-	x333, x334 = bits.Add64(x297, x320, uint64(p384Uint1(x332)))
-	var x335 uint64
-	var x336 uint64
-	x335, x336 = bits.Add64(x299, x322, uint64(p384Uint1(x334)))
-	var x337 uint64
-	_, x337 = bits.Mul64(x323, 0x100000001)
-	var x339 uint64
-	var x340 uint64
-	x340, x339 = bits.Mul64(x337, 0xffffffffffffffff)
-	var x341 uint64
-	var x342 uint64
-	x342, x341 = bits.Mul64(x337, 0xffffffffffffffff)
-	var x343 uint64
-	var x344 uint64
-	x344, x343 = bits.Mul64(x337, 0xffffffffffffffff)
-	var x345 uint64
-	var x346 uint64
-	x346, x345 = bits.Mul64(x337, 0xfffffffffffffffe)
-	var x347 uint64
-	var x348 uint64
-	x348, x347 = bits.Mul64(x337, 0xffffffff00000000)
-	var x349 uint64
-	var x350 uint64
-	x350, x349 = bits.Mul64(x337, 0xffffffff)
-	var x351 uint64
-	var x352 uint64
-	x351, x352 = bits.Add64(x350, x347, uint64(0x0))
-	var x353 uint64
-	var x354 uint64
-	x353, x354 = bits.Add64(x348, x345, uint64(p384Uint1(x352)))
-	var x355 uint64
-	var x356 uint64
-	x355, x356 = bits.Add64(x346, x343, uint64(p384Uint1(x354)))
-	var x357 uint64
-	var x358 uint64
-	x357, x358 = bits.Add64(x344, x341, uint64(p384Uint1(x356)))
-	var x359 uint64
-	var x360 uint64
-	x359, x360 = bits.Add64(x342, x339, uint64(p384Uint1(x358)))
-	x361 := (uint64(p384Uint1(x360)) + x340)
-	var x363 uint64
-	_, x363 = bits.Add64(x323, x349, uint64(0x0))
-	var x364 uint64
-	var x365 uint64
-	x364, x365 = bits.Add64(x325, x351, uint64(p384Uint1(x363)))
-	var x366 uint64
-	var x367 uint64
-	x366, x367 = bits.Add64(x327, x353, uint64(p384Uint1(x365)))
-	var x368 uint64
-	var x369 uint64
-	x368, x369 = bits.Add64(x329, x355, uint64(p384Uint1(x367)))
-	var x370 uint64
-	var x371 uint64
-	x370, x371 = bits.Add64(x331, x357, uint64(p384Uint1(x369)))
-	var x372 uint64
-	var x373 uint64
-	x372, x373 = bits.Add64(x333, x359, uint64(p384Uint1(x371)))
-	var x374 uint64
-	var x375 uint64
-	x374, x375 = bits.Add64(x335, x361, uint64(p384Uint1(x373)))
-	x376 := (uint64(p384Uint1(x375)) + uint64(p384Uint1(x336)))
-	var x377 uint64
-	var x378 uint64
-	x378, x377 = bits.Mul64(x5, arg2[5])
-	var x379 uint64
-	var x380 uint64
-	x380, x379 = bits.Mul64(x5, arg2[4])
-	var x381 uint64
-	var x382 uint64
-	x382, x381 = bits.Mul64(x5, arg2[3])
-	var x383 uint64
-	var x384 uint64
-	x384, x383 = bits.Mul64(x5, arg2[2])
-	var x385 uint64
-	var x386 uint64
-	x386, x385 = bits.Mul64(x5, arg2[1])
-	var x387 uint64
-	var x388 uint64
-	x388, x387 = bits.Mul64(x5, arg2[0])
-	var x389 uint64
-	var x390 uint64
-	x389, x390 = bits.Add64(x388, x385, uint64(0x0))
-	var x391 uint64
-	var x392 uint64
-	x391, x392 = bits.Add64(x386, x383, uint64(p384Uint1(x390)))
-	var x393 uint64
-	var x394 uint64
-	x393, x394 = bits.Add64(x384, x381, uint64(p384Uint1(x392)))
-	var x395 uint64
-	var x396 uint64
-	x395, x396 = bits.Add64(x382, x379, uint64(p384Uint1(x394)))
-	var x397 uint64
-	var x398 uint64
-	x397, x398 = bits.Add64(x380, x377, uint64(p384Uint1(x396)))
-	x399 := (uint64(p384Uint1(x398)) + x378)
-	var x400 uint64
-	var x401 uint64
-	x400, x401 = bits.Add64(x364, x387, uint64(0x0))
-	var x402 uint64
-	var x403 uint64
-	x402, x403 = bits.Add64(x366, x389, uint64(p384Uint1(x401)))
-	var x404 uint64
-	var x405 uint64
-	x404, x405 = bits.Add64(x368, x391, uint64(p384Uint1(x403)))
-	var x406 uint64
-	var x407 uint64
-	x406, x407 = bits.Add64(x370, x393, uint64(p384Uint1(x405)))
-	var x408 uint64
-	var x409 uint64
-	x408, x409 = bits.Add64(x372, x395, uint64(p384Uint1(x407)))
-	var x410 uint64
-	var x411 uint64
-	x410, x411 = bits.Add64(x374, x397, uint64(p384Uint1(x409)))
-	var x412 uint64
-	var x413 uint64
-	x412, x413 = bits.Add64(x376, x399, uint64(p384Uint1(x411)))
-	var x414 uint64
-	_, x414 = bits.Mul64(x400, 0x100000001)
-	var x416 uint64
-	var x417 uint64
-	x417, x416 = bits.Mul64(x414, 0xffffffffffffffff)
-	var x418 uint64
-	var x419 uint64
-	x419, x418 = bits.Mul64(x414, 0xffffffffffffffff)
-	var x420 uint64
-	var x421 uint64
-	x421, x420 = bits.Mul64(x414, 0xffffffffffffffff)
-	var x422 uint64
-	var x423 uint64
-	x423, x422 = bits.Mul64(x414, 0xfffffffffffffffe)
-	var x424 uint64
-	var x425 uint64
-	x425, x424 = bits.Mul64(x414, 0xffffffff00000000)
-	var x426 uint64
-	var x427 uint64
-	x427, x426 = bits.Mul64(x414, 0xffffffff)
-	var x428 uint64
-	var x429 uint64
-	x428, x429 = bits.Add64(x427, x424, uint64(0x0))
-	var x430 uint64
-	var x431 uint64
-	x430, x431 = bits.Add64(x425, x422, uint64(p384Uint1(x429)))
-	var x432 uint64
-	var x433 uint64
-	x432, x433 = bits.Add64(x423, x420, uint64(p384Uint1(x431)))
-	var x434 uint64
-	var x435 uint64
-	x434, x435 = bits.Add64(x421, x418, uint64(p384Uint1(x433)))
-	var x436 uint64
-	var x437 uint64
-	x436, x437 = bits.Add64(x419, x416, uint64(p384Uint1(x435)))
-	x438 := (uint64(p384Uint1(x437)) + x417)
-	var x440 uint64
-	_, x440 = bits.Add64(x400, x426, uint64(0x0))
-	var x441 uint64
-	var x442 uint64
-	x441, x442 = bits.Add64(x402, x428, uint64(p384Uint1(x440)))
-	var x443 uint64
-	var x444 uint64
-	x443, x444 = bits.Add64(x404, x430, uint64(p384Uint1(x442)))
-	var x445 uint64
-	var x446 uint64
-	x445, x446 = bits.Add64(x406, x432, uint64(p384Uint1(x444)))
-	var x447 uint64
-	var x448 uint64
-	x447, x448 = bits.Add64(x408, x434, uint64(p384Uint1(x446)))
-	var x449 uint64
-	var x450 uint64
-	x449, x450 = bits.Add64(x410, x436, uint64(p384Uint1(x448)))
-	var x451 uint64
-	var x452 uint64
-	x451, x452 = bits.Add64(x412, x438, uint64(p384Uint1(x450)))
-	x453 := (uint64(p384Uint1(x452)) + uint64(p384Uint1(x413)))
-	var x454 uint64
-	var x455 uint64
-	x454, x455 = bits.Sub64(x441, 0xffffffff, uint64(0x0))
-	var x456 uint64
-	var x457 uint64
-	x456, x457 = bits.Sub64(x443, 0xffffffff00000000, uint64(p384Uint1(x455)))
-	var x458 uint64
-	var x459 uint64
-	x458, x459 = bits.Sub64(x445, 0xfffffffffffffffe, uint64(p384Uint1(x457)))
-	var x460 uint64
-	var x461 uint64
-	x460, x461 = bits.Sub64(x447, 0xffffffffffffffff, uint64(p384Uint1(x459)))
-	var x462 uint64
-	var x463 uint64
-	x462, x463 = bits.Sub64(x449, 0xffffffffffffffff, uint64(p384Uint1(x461)))
-	var x464 uint64
-	var x465 uint64
-	x464, x465 = bits.Sub64(x451, 0xffffffffffffffff, uint64(p384Uint1(x463)))
-	var x467 uint64
-	_, x467 = bits.Sub64(x453, uint64(0x0), uint64(p384Uint1(x465)))
-	var x468 uint64
-	p384CmovznzU64(&x468, p384Uint1(x467), x454, x441)
-	var x469 uint64
-	p384CmovznzU64(&x469, p384Uint1(x467), x456, x443)
-	var x470 uint64
-	p384CmovznzU64(&x470, p384Uint1(x467), x458, x445)
-	var x471 uint64
-	p384CmovznzU64(&x471, p384Uint1(x467), x460, x447)
-	var x472 uint64
-	p384CmovznzU64(&x472, p384Uint1(x467), x462, x449)
-	var x473 uint64
-	p384CmovznzU64(&x473, p384Uint1(x467), x464, x451)
-	out1[0] = x468
-	out1[1] = x469
-	out1[2] = x470
-	out1[3] = x471
-	out1[4] = x472
-	out1[5] = x473
-}
-
-// p384Square squares a field element in the Montgomery domain.
-//
-// Preconditions:
-//   0 ≤ eval arg1 < m
-// Postconditions:
-//   eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) * eval (from_montgomery arg1)) mod m
-//   0 ≤ eval out1 < m
-//
-func p384Square(out1 *p384MontgomeryDomainFieldElement, arg1 *p384MontgomeryDomainFieldElement) {
-	x1 := arg1[1]
-	x2 := arg1[2]
-	x3 := arg1[3]
-	x4 := arg1[4]
-	x5 := arg1[5]
-	x6 := arg1[0]
-	var x7 uint64
-	var x8 uint64
-	x8, x7 = bits.Mul64(x6, arg1[5])
-	var x9 uint64
-	var x10 uint64
-	x10, x9 = bits.Mul64(x6, arg1[4])
-	var x11 uint64
-	var x12 uint64
-	x12, x11 = bits.Mul64(x6, arg1[3])
-	var x13 uint64
-	var x14 uint64
-	x14, x13 = bits.Mul64(x6, arg1[2])
-	var x15 uint64
-	var x16 uint64
-	x16, x15 = bits.Mul64(x6, arg1[1])
-	var x17 uint64
-	var x18 uint64
-	x18, x17 = bits.Mul64(x6, arg1[0])
-	var x19 uint64
-	var x20 uint64
-	x19, x20 = bits.Add64(x18, x15, uint64(0x0))
-	var x21 uint64
-	var x22 uint64
-	x21, x22 = bits.Add64(x16, x13, uint64(p384Uint1(x20)))
-	var x23 uint64
-	var x24 uint64
-	x23, x24 = bits.Add64(x14, x11, uint64(p384Uint1(x22)))
-	var x25 uint64
-	var x26 uint64
-	x25, x26 = bits.Add64(x12, x9, uint64(p384Uint1(x24)))
-	var x27 uint64
-	var x28 uint64
-	x27, x28 = bits.Add64(x10, x7, uint64(p384Uint1(x26)))
-	x29 := (uint64(p384Uint1(x28)) + x8)
-	var x30 uint64
-	_, x30 = bits.Mul64(x17, 0x100000001)
-	var x32 uint64
-	var x33 uint64
-	x33, x32 = bits.Mul64(x30, 0xffffffffffffffff)
-	var x34 uint64
-	var x35 uint64
-	x35, x34 = bits.Mul64(x30, 0xffffffffffffffff)
-	var x36 uint64
-	var x37 uint64
-	x37, x36 = bits.Mul64(x30, 0xffffffffffffffff)
-	var x38 uint64
-	var x39 uint64
-	x39, x38 = bits.Mul64(x30, 0xfffffffffffffffe)
-	var x40 uint64
-	var x41 uint64
-	x41, x40 = bits.Mul64(x30, 0xffffffff00000000)
-	var x42 uint64
-	var x43 uint64
-	x43, x42 = bits.Mul64(x30, 0xffffffff)
-	var x44 uint64
-	var x45 uint64
-	x44, x45 = bits.Add64(x43, x40, uint64(0x0))
-	var x46 uint64
-	var x47 uint64
-	x46, x47 = bits.Add64(x41, x38, uint64(p384Uint1(x45)))
-	var x48 uint64
-	var x49 uint64
-	x48, x49 = bits.Add64(x39, x36, uint64(p384Uint1(x47)))
-	var x50 uint64
-	var x51 uint64
-	x50, x51 = bits.Add64(x37, x34, uint64(p384Uint1(x49)))
-	var x52 uint64
-	var x53 uint64
-	x52, x53 = bits.Add64(x35, x32, uint64(p384Uint1(x51)))
-	x54 := (uint64(p384Uint1(x53)) + x33)
-	var x56 uint64
-	_, x56 = bits.Add64(x17, x42, uint64(0x0))
-	var x57 uint64
-	var x58 uint64
-	x57, x58 = bits.Add64(x19, x44, uint64(p384Uint1(x56)))
-	var x59 uint64
-	var x60 uint64
-	x59, x60 = bits.Add64(x21, x46, uint64(p384Uint1(x58)))
-	var x61 uint64
-	var x62 uint64
-	x61, x62 = bits.Add64(x23, x48, uint64(p384Uint1(x60)))
-	var x63 uint64
-	var x64 uint64
-	x63, x64 = bits.Add64(x25, x50, uint64(p384Uint1(x62)))
-	var x65 uint64
-	var x66 uint64
-	x65, x66 = bits.Add64(x27, x52, uint64(p384Uint1(x64)))
-	var x67 uint64
-	var x68 uint64
-	x67, x68 = bits.Add64(x29, x54, uint64(p384Uint1(x66)))
-	var x69 uint64
-	var x70 uint64
-	x70, x69 = bits.Mul64(x1, arg1[5])
-	var x71 uint64
-	var x72 uint64
-	x72, x71 = bits.Mul64(x1, arg1[4])
-	var x73 uint64
-	var x74 uint64
-	x74, x73 = bits.Mul64(x1, arg1[3])
-	var x75 uint64
-	var x76 uint64
-	x76, x75 = bits.Mul64(x1, arg1[2])
-	var x77 uint64
-	var x78 uint64
-	x78, x77 = bits.Mul64(x1, arg1[1])
-	var x79 uint64
-	var x80 uint64
-	x80, x79 = bits.Mul64(x1, arg1[0])
-	var x81 uint64
-	var x82 uint64
-	x81, x82 = bits.Add64(x80, x77, uint64(0x0))
-	var x83 uint64
-	var x84 uint64
-	x83, x84 = bits.Add64(x78, x75, uint64(p384Uint1(x82)))
-	var x85 uint64
-	var x86 uint64
-	x85, x86 = bits.Add64(x76, x73, uint64(p384Uint1(x84)))
-	var x87 uint64
-	var x88 uint64
-	x87, x88 = bits.Add64(x74, x71, uint64(p384Uint1(x86)))
-	var x89 uint64
-	var x90 uint64
-	x89, x90 = bits.Add64(x72, x69, uint64(p384Uint1(x88)))
-	x91 := (uint64(p384Uint1(x90)) + x70)
-	var x92 uint64
-	var x93 uint64
-	x92, x93 = bits.Add64(x57, x79, uint64(0x0))
-	var x94 uint64
-	var x95 uint64
-	x94, x95 = bits.Add64(x59, x81, uint64(p384Uint1(x93)))
-	var x96 uint64
-	var x97 uint64
-	x96, x97 = bits.Add64(x61, x83, uint64(p384Uint1(x95)))
-	var x98 uint64
-	var x99 uint64
-	x98, x99 = bits.Add64(x63, x85, uint64(p384Uint1(x97)))
-	var x100 uint64
-	var x101 uint64
-	x100, x101 = bits.Add64(x65, x87, uint64(p384Uint1(x99)))
-	var x102 uint64
-	var x103 uint64
-	x102, x103 = bits.Add64(x67, x89, uint64(p384Uint1(x101)))
-	var x104 uint64
-	var x105 uint64
-	x104, x105 = bits.Add64(uint64(p384Uint1(x68)), x91, uint64(p384Uint1(x103)))
-	var x106 uint64
-	_, x106 = bits.Mul64(x92, 0x100000001)
-	var x108 uint64
-	var x109 uint64
-	x109, x108 = bits.Mul64(x106, 0xffffffffffffffff)
-	var x110 uint64
-	var x111 uint64
-	x111, x110 = bits.Mul64(x106, 0xffffffffffffffff)
-	var x112 uint64
-	var x113 uint64
-	x113, x112 = bits.Mul64(x106, 0xffffffffffffffff)
-	var x114 uint64
-	var x115 uint64
-	x115, x114 = bits.Mul64(x106, 0xfffffffffffffffe)
-	var x116 uint64
-	var x117 uint64
-	x117, x116 = bits.Mul64(x106, 0xffffffff00000000)
-	var x118 uint64
-	var x119 uint64
-	x119, x118 = bits.Mul64(x106, 0xffffffff)
-	var x120 uint64
-	var x121 uint64
-	x120, x121 = bits.Add64(x119, x116, uint64(0x0))
-	var x122 uint64
-	var x123 uint64
-	x122, x123 = bits.Add64(x117, x114, uint64(p384Uint1(x121)))
-	var x124 uint64
-	var x125 uint64
-	x124, x125 = bits.Add64(x115, x112, uint64(p384Uint1(x123)))
-	var x126 uint64
-	var x127 uint64
-	x126, x127 = bits.Add64(x113, x110, uint64(p384Uint1(x125)))
-	var x128 uint64
-	var x129 uint64
-	x128, x129 = bits.Add64(x111, x108, uint64(p384Uint1(x127)))
-	x130 := (uint64(p384Uint1(x129)) + x109)
-	var x132 uint64
-	_, x132 = bits.Add64(x92, x118, uint64(0x0))
-	var x133 uint64
-	var x134 uint64
-	x133, x134 = bits.Add64(x94, x120, uint64(p384Uint1(x132)))
-	var x135 uint64
-	var x136 uint64
-	x135, x136 = bits.Add64(x96, x122, uint64(p384Uint1(x134)))
-	var x137 uint64
-	var x138 uint64
-	x137, x138 = bits.Add64(x98, x124, uint64(p384Uint1(x136)))
-	var x139 uint64
-	var x140 uint64
-	x139, x140 = bits.Add64(x100, x126, uint64(p384Uint1(x138)))
-	var x141 uint64
-	var x142 uint64
-	x141, x142 = bits.Add64(x102, x128, uint64(p384Uint1(x140)))
-	var x143 uint64
-	var x144 uint64
-	x143, x144 = bits.Add64(x104, x130, uint64(p384Uint1(x142)))
-	x145 := (uint64(p384Uint1(x144)) + uint64(p384Uint1(x105)))
-	var x146 uint64
-	var x147 uint64
-	x147, x146 = bits.Mul64(x2, arg1[5])
-	var x148 uint64
-	var x149 uint64
-	x149, x148 = bits.Mul64(x2, arg1[4])
-	var x150 uint64
-	var x151 uint64
-	x151, x150 = bits.Mul64(x2, arg1[3])
-	var x152 uint64
-	var x153 uint64
-	x153, x152 = bits.Mul64(x2, arg1[2])
-	var x154 uint64
-	var x155 uint64
-	x155, x154 = bits.Mul64(x2, arg1[1])
-	var x156 uint64
-	var x157 uint64
-	x157, x156 = bits.Mul64(x2, arg1[0])
-	var x158 uint64
-	var x159 uint64
-	x158, x159 = bits.Add64(x157, x154, uint64(0x0))
-	var x160 uint64
-	var x161 uint64
-	x160, x161 = bits.Add64(x155, x152, uint64(p384Uint1(x159)))
-	var x162 uint64
-	var x163 uint64
-	x162, x163 = bits.Add64(x153, x150, uint64(p384Uint1(x161)))
-	var x164 uint64
-	var x165 uint64
-	x164, x165 = bits.Add64(x151, x148, uint64(p384Uint1(x163)))
-	var x166 uint64
-	var x167 uint64
-	x166, x167 = bits.Add64(x149, x146, uint64(p384Uint1(x165)))
-	x168 := (uint64(p384Uint1(x167)) + x147)
-	var x169 uint64
-	var x170 uint64
-	x169, x170 = bits.Add64(x133, x156, uint64(0x0))
-	var x171 uint64
-	var x172 uint64
-	x171, x172 = bits.Add64(x135, x158, uint64(p384Uint1(x170)))
-	var x173 uint64
-	var x174 uint64
-	x173, x174 = bits.Add64(x137, x160, uint64(p384Uint1(x172)))
-	var x175 uint64
-	var x176 uint64
-	x175, x176 = bits.Add64(x139, x162, uint64(p384Uint1(x174)))
-	var x177 uint64
-	var x178 uint64
-	x177, x178 = bits.Add64(x141, x164, uint64(p384Uint1(x176)))
-	var x179 uint64
-	var x180 uint64
-	x179, x180 = bits.Add64(x143, x166, uint64(p384Uint1(x178)))
-	var x181 uint64
-	var x182 uint64
-	x181, x182 = bits.Add64(x145, x168, uint64(p384Uint1(x180)))
-	var x183 uint64
-	_, x183 = bits.Mul64(x169, 0x100000001)
-	var x185 uint64
-	var x186 uint64
-	x186, x185 = bits.Mul64(x183, 0xffffffffffffffff)
-	var x187 uint64
-	var x188 uint64
-	x188, x187 = bits.Mul64(x183, 0xffffffffffffffff)
-	var x189 uint64
-	var x190 uint64
-	x190, x189 = bits.Mul64(x183, 0xffffffffffffffff)
-	var x191 uint64
-	var x192 uint64
-	x192, x191 = bits.Mul64(x183, 0xfffffffffffffffe)
-	var x193 uint64
-	var x194 uint64
-	x194, x193 = bits.Mul64(x183, 0xffffffff00000000)
-	var x195 uint64
-	var x196 uint64
-	x196, x195 = bits.Mul64(x183, 0xffffffff)
-	var x197 uint64
-	var x198 uint64
-	x197, x198 = bits.Add64(x196, x193, uint64(0x0))
-	var x199 uint64
-	var x200 uint64
-	x199, x200 = bits.Add64(x194, x191, uint64(p384Uint1(x198)))
-	var x201 uint64
-	var x202 uint64
-	x201, x202 = bits.Add64(x192, x189, uint64(p384Uint1(x200)))
-	var x203 uint64
-	var x204 uint64
-	x203, x204 = bits.Add64(x190, x187, uint64(p384Uint1(x202)))
-	var x205 uint64
-	var x206 uint64
-	x205, x206 = bits.Add64(x188, x185, uint64(p384Uint1(x204)))
-	x207 := (uint64(p384Uint1(x206)) + x186)
-	var x209 uint64
-	_, x209 = bits.Add64(x169, x195, uint64(0x0))
-	var x210 uint64
-	var x211 uint64
-	x210, x211 = bits.Add64(x171, x197, uint64(p384Uint1(x209)))
-	var x212 uint64
-	var x213 uint64
-	x212, x213 = bits.Add64(x173, x199, uint64(p384Uint1(x211)))
-	var x214 uint64
-	var x215 uint64
-	x214, x215 = bits.Add64(x175, x201, uint64(p384Uint1(x213)))
-	var x216 uint64
-	var x217 uint64
-	x216, x217 = bits.Add64(x177, x203, uint64(p384Uint1(x215)))
-	var x218 uint64
-	var x219 uint64
-	x218, x219 = bits.Add64(x179, x205, uint64(p384Uint1(x217)))
-	var x220 uint64
-	var x221 uint64
-	x220, x221 = bits.Add64(x181, x207, uint64(p384Uint1(x219)))
-	x222 := (uint64(p384Uint1(x221)) + uint64(p384Uint1(x182)))
-	var x223 uint64
-	var x224 uint64
-	x224, x223 = bits.Mul64(x3, arg1[5])
-	var x225 uint64
-	var x226 uint64
-	x226, x225 = bits.Mul64(x3, arg1[4])
-	var x227 uint64
-	var x228 uint64
-	x228, x227 = bits.Mul64(x3, arg1[3])
-	var x229 uint64
-	var x230 uint64
-	x230, x229 = bits.Mul64(x3, arg1[2])
-	var x231 uint64
-	var x232 uint64
-	x232, x231 = bits.Mul64(x3, arg1[1])
-	var x233 uint64
-	var x234 uint64
-	x234, x233 = bits.Mul64(x3, arg1[0])
-	var x235 uint64
-	var x236 uint64
-	x235, x236 = bits.Add64(x234, x231, uint64(0x0))
-	var x237 uint64
-	var x238 uint64
-	x237, x238 = bits.Add64(x232, x229, uint64(p384Uint1(x236)))
-	var x239 uint64
-	var x240 uint64
-	x239, x240 = bits.Add64(x230, x227, uint64(p384Uint1(x238)))
-	var x241 uint64
-	var x242 uint64
-	x241, x242 = bits.Add64(x228, x225, uint64(p384Uint1(x240)))
-	var x243 uint64
-	var x244 uint64
-	x243, x244 = bits.Add64(x226, x223, uint64(p384Uint1(x242)))
-	x245 := (uint64(p384Uint1(x244)) + x224)
-	var x246 uint64
-	var x247 uint64
-	x246, x247 = bits.Add64(x210, x233, uint64(0x0))
-	var x248 uint64
-	var x249 uint64
-	x248, x249 = bits.Add64(x212, x235, uint64(p384Uint1(x247)))
-	var x250 uint64
-	var x251 uint64
-	x250, x251 = bits.Add64(x214, x237, uint64(p384Uint1(x249)))
-	var x252 uint64
-	var x253 uint64
-	x252, x253 = bits.Add64(x216, x239, uint64(p384Uint1(x251)))
-	var x254 uint64
-	var x255 uint64
-	x254, x255 = bits.Add64(x218, x241, uint64(p384Uint1(x253)))
-	var x256 uint64
-	var x257 uint64
-	x256, x257 = bits.Add64(x220, x243, uint64(p384Uint1(x255)))
-	var x258 uint64
-	var x259 uint64
-	x258, x259 = bits.Add64(x222, x245, uint64(p384Uint1(x257)))
-	var x260 uint64
-	_, x260 = bits.Mul64(x246, 0x100000001)
-	var x262 uint64
-	var x263 uint64
-	x263, x262 = bits.Mul64(x260, 0xffffffffffffffff)
-	var x264 uint64
-	var x265 uint64
-	x265, x264 = bits.Mul64(x260, 0xffffffffffffffff)
-	var x266 uint64
-	var x267 uint64
-	x267, x266 = bits.Mul64(x260, 0xffffffffffffffff)
-	var x268 uint64
-	var x269 uint64
-	x269, x268 = bits.Mul64(x260, 0xfffffffffffffffe)
-	var x270 uint64
-	var x271 uint64
-	x271, x270 = bits.Mul64(x260, 0xffffffff00000000)
-	var x272 uint64
-	var x273 uint64
-	x273, x272 = bits.Mul64(x260, 0xffffffff)
-	var x274 uint64
-	var x275 uint64
-	x274, x275 = bits.Add64(x273, x270, uint64(0x0))
-	var x276 uint64
-	var x277 uint64
-	x276, x277 = bits.Add64(x271, x268, uint64(p384Uint1(x275)))
-	var x278 uint64
-	var x279 uint64
-	x278, x279 = bits.Add64(x269, x266, uint64(p384Uint1(x277)))
-	var x280 uint64
-	var x281 uint64
-	x280, x281 = bits.Add64(x267, x264, uint64(p384Uint1(x279)))
-	var x282 uint64
-	var x283 uint64
-	x282, x283 = bits.Add64(x265, x262, uint64(p384Uint1(x281)))
-	x284 := (uint64(p384Uint1(x283)) + x263)
-	var x286 uint64
-	_, x286 = bits.Add64(x246, x272, uint64(0x0))
-	var x287 uint64
-	var x288 uint64
-	x287, x288 = bits.Add64(x248, x274, uint64(p384Uint1(x286)))
-	var x289 uint64
-	var x290 uint64
-	x289, x290 = bits.Add64(x250, x276, uint64(p384Uint1(x288)))
-	var x291 uint64
-	var x292 uint64
-	x291, x292 = bits.Add64(x252, x278, uint64(p384Uint1(x290)))
-	var x293 uint64
-	var x294 uint64
-	x293, x294 = bits.Add64(x254, x280, uint64(p384Uint1(x292)))
-	var x295 uint64
-	var x296 uint64
-	x295, x296 = bits.Add64(x256, x282, uint64(p384Uint1(x294)))
-	var x297 uint64
-	var x298 uint64
-	x297, x298 = bits.Add64(x258, x284, uint64(p384Uint1(x296)))
-	x299 := (uint64(p384Uint1(x298)) + uint64(p384Uint1(x259)))
-	var x300 uint64
-	var x301 uint64
-	x301, x300 = bits.Mul64(x4, arg1[5])
-	var x302 uint64
-	var x303 uint64
-	x303, x302 = bits.Mul64(x4, arg1[4])
-	var x304 uint64
-	var x305 uint64
-	x305, x304 = bits.Mul64(x4, arg1[3])
-	var x306 uint64
-	var x307 uint64
-	x307, x306 = bits.Mul64(x4, arg1[2])
-	var x308 uint64
-	var x309 uint64
-	x309, x308 = bits.Mul64(x4, arg1[1])
-	var x310 uint64
-	var x311 uint64
-	x311, x310 = bits.Mul64(x4, arg1[0])
-	var x312 uint64
-	var x313 uint64
-	x312, x313 = bits.Add64(x311, x308, uint64(0x0))
-	var x314 uint64
-	var x315 uint64
-	x314, x315 = bits.Add64(x309, x306, uint64(p384Uint1(x313)))
-	var x316 uint64
-	var x317 uint64
-	x316, x317 = bits.Add64(x307, x304, uint64(p384Uint1(x315)))
-	var x318 uint64
-	var x319 uint64
-	x318, x319 = bits.Add64(x305, x302, uint64(p384Uint1(x317)))
-	var x320 uint64
-	var x321 uint64
-	x320, x321 = bits.Add64(x303, x300, uint64(p384Uint1(x319)))
-	x322 := (uint64(p384Uint1(x321)) + x301)
-	var x323 uint64
-	var x324 uint64
-	x323, x324 = bits.Add64(x287, x310, uint64(0x0))
-	var x325 uint64
-	var x326 uint64
-	x325, x326 = bits.Add64(x289, x312, uint64(p384Uint1(x324)))
-	var x327 uint64
-	var x328 uint64
-	x327, x328 = bits.Add64(x291, x314, uint64(p384Uint1(x326)))
-	var x329 uint64
-	var x330 uint64
-	x329, x330 = bits.Add64(x293, x316, uint64(p384Uint1(x328)))
-	var x331 uint64
-	var x332 uint64
-	x331, x332 = bits.Add64(x295, x318, uint64(p384Uint1(x330)))
-	var x333 uint64
-	var x334 uint64
-	x333, x334 = bits.Add64(x297, x320, uint64(p384Uint1(x332)))
-	var x335 uint64
-	var x336 uint64
-	x335, x336 = bits.Add64(x299, x322, uint64(p384Uint1(x334)))
-	var x337 uint64
-	_, x337 = bits.Mul64(x323, 0x100000001)
-	var x339 uint64
-	var x340 uint64
-	x340, x339 = bits.Mul64(x337, 0xffffffffffffffff)
-	var x341 uint64
-	var x342 uint64
-	x342, x341 = bits.Mul64(x337, 0xffffffffffffffff)
-	var x343 uint64
-	var x344 uint64
-	x344, x343 = bits.Mul64(x337, 0xffffffffffffffff)
-	var x345 uint64
-	var x346 uint64
-	x346, x345 = bits.Mul64(x337, 0xfffffffffffffffe)
-	var x347 uint64
-	var x348 uint64
-	x348, x347 = bits.Mul64(x337, 0xffffffff00000000)
-	var x349 uint64
-	var x350 uint64
-	x350, x349 = bits.Mul64(x337, 0xffffffff)
-	var x351 uint64
-	var x352 uint64
-	x351, x352 = bits.Add64(x350, x347, uint64(0x0))
-	var x353 uint64
-	var x354 uint64
-	x353, x354 = bits.Add64(x348, x345, uint64(p384Uint1(x352)))
-	var x355 uint64
-	var x356 uint64
-	x355, x356 = bits.Add64(x346, x343, uint64(p384Uint1(x354)))
-	var x357 uint64
-	var x358 uint64
-	x357, x358 = bits.Add64(x344, x341, uint64(p384Uint1(x356)))
-	var x359 uint64
-	var x360 uint64
-	x359, x360 = bits.Add64(x342, x339, uint64(p384Uint1(x358)))
-	x361 := (uint64(p384Uint1(x360)) + x340)
-	var x363 uint64
-	_, x363 = bits.Add64(x323, x349, uint64(0x0))
-	var x364 uint64
-	var x365 uint64
-	x364, x365 = bits.Add64(x325, x351, uint64(p384Uint1(x363)))
-	var x366 uint64
-	var x367 uint64
-	x366, x367 = bits.Add64(x327, x353, uint64(p384Uint1(x365)))
-	var x368 uint64
-	var x369 uint64
-	x368, x369 = bits.Add64(x329, x355, uint64(p384Uint1(x367)))
-	var x370 uint64
-	var x371 uint64
-	x370, x371 = bits.Add64(x331, x357, uint64(p384Uint1(x369)))
-	var x372 uint64
-	var x373 uint64
-	x372, x373 = bits.Add64(x333, x359, uint64(p384Uint1(x371)))
-	var x374 uint64
-	var x375 uint64
-	x374, x375 = bits.Add64(x335, x361, uint64(p384Uint1(x373)))
-	x376 := (uint64(p384Uint1(x375)) + uint64(p384Uint1(x336)))
-	var x377 uint64
-	var x378 uint64
-	x378, x377 = bits.Mul64(x5, arg1[5])
-	var x379 uint64
-	var x380 uint64
-	x380, x379 = bits.Mul64(x5, arg1[4])
-	var x381 uint64
-	var x382 uint64
-	x382, x381 = bits.Mul64(x5, arg1[3])
-	var x383 uint64
-	var x384 uint64
-	x384, x383 = bits.Mul64(x5, arg1[2])
-	var x385 uint64
-	var x386 uint64
-	x386, x385 = bits.Mul64(x5, arg1[1])
-	var x387 uint64
-	var x388 uint64
-	x388, x387 = bits.Mul64(x5, arg1[0])
-	var x389 uint64
-	var x390 uint64
-	x389, x390 = bits.Add64(x388, x385, uint64(0x0))
-	var x391 uint64
-	var x392 uint64
-	x391, x392 = bits.Add64(x386, x383, uint64(p384Uint1(x390)))
-	var x393 uint64
-	var x394 uint64
-	x393, x394 = bits.Add64(x384, x381, uint64(p384Uint1(x392)))
-	var x395 uint64
-	var x396 uint64
-	x395, x396 = bits.Add64(x382, x379, uint64(p384Uint1(x394)))
-	var x397 uint64
-	var x398 uint64
-	x397, x398 = bits.Add64(x380, x377, uint64(p384Uint1(x396)))
-	x399 := (uint64(p384Uint1(x398)) + x378)
-	var x400 uint64
-	var x401 uint64
-	x400, x401 = bits.Add64(x364, x387, uint64(0x0))
-	var x402 uint64
-	var x403 uint64
-	x402, x403 = bits.Add64(x366, x389, uint64(p384Uint1(x401)))
-	var x404 uint64
-	var x405 uint64
-	x404, x405 = bits.Add64(x368, x391, uint64(p384Uint1(x403)))
-	var x406 uint64
-	var x407 uint64
-	x406, x407 = bits.Add64(x370, x393, uint64(p384Uint1(x405)))
-	var x408 uint64
-	var x409 uint64
-	x408, x409 = bits.Add64(x372, x395, uint64(p384Uint1(x407)))
-	var x410 uint64
-	var x411 uint64
-	x410, x411 = bits.Add64(x374, x397, uint64(p384Uint1(x409)))
-	var x412 uint64
-	var x413 uint64
-	x412, x413 = bits.Add64(x376, x399, uint64(p384Uint1(x411)))
-	var x414 uint64
-	_, x414 = bits.Mul64(x400, 0x100000001)
-	var x416 uint64
-	var x417 uint64
-	x417, x416 = bits.Mul64(x414, 0xffffffffffffffff)
-	var x418 uint64
-	var x419 uint64
-	x419, x418 = bits.Mul64(x414, 0xffffffffffffffff)
-	var x420 uint64
-	var x421 uint64
-	x421, x420 = bits.Mul64(x414, 0xffffffffffffffff)
-	var x422 uint64
-	var x423 uint64
-	x423, x422 = bits.Mul64(x414, 0xfffffffffffffffe)
-	var x424 uint64
-	var x425 uint64
-	x425, x424 = bits.Mul64(x414, 0xffffffff00000000)
-	var x426 uint64
-	var x427 uint64
-	x427, x426 = bits.Mul64(x414, 0xffffffff)
-	var x428 uint64
-	var x429 uint64
-	x428, x429 = bits.Add64(x427, x424, uint64(0x0))
-	var x430 uint64
-	var x431 uint64
-	x430, x431 = bits.Add64(x425, x422, uint64(p384Uint1(x429)))
-	var x432 uint64
-	var x433 uint64
-	x432, x433 = bits.Add64(x423, x420, uint64(p384Uint1(x431)))
-	var x434 uint64
-	var x435 uint64
-	x434, x435 = bits.Add64(x421, x418, uint64(p384Uint1(x433)))
-	var x436 uint64
-	var x437 uint64
-	x436, x437 = bits.Add64(x419, x416, uint64(p384Uint1(x435)))
-	x438 := (uint64(p384Uint1(x437)) + x417)
-	var x440 uint64
-	_, x440 = bits.Add64(x400, x426, uint64(0x0))
-	var x441 uint64
-	var x442 uint64
-	x441, x442 = bits.Add64(x402, x428, uint64(p384Uint1(x440)))
-	var x443 uint64
-	var x444 uint64
-	x443, x444 = bits.Add64(x404, x430, uint64(p384Uint1(x442)))
-	var x445 uint64
-	var x446 uint64
-	x445, x446 = bits.Add64(x406, x432, uint64(p384Uint1(x444)))
-	var x447 uint64
-	var x448 uint64
-	x447, x448 = bits.Add64(x408, x434, uint64(p384Uint1(x446)))
-	var x449 uint64
-	var x450 uint64
-	x449, x450 = bits.Add64(x410, x436, uint64(p384Uint1(x448)))
-	var x451 uint64
-	var x452 uint64
-	x451, x452 = bits.Add64(x412, x438, uint64(p384Uint1(x450)))
-	x453 := (uint64(p384Uint1(x452)) + uint64(p384Uint1(x413)))
-	var x454 uint64
-	var x455 uint64
-	x454, x455 = bits.Sub64(x441, 0xffffffff, uint64(0x0))
-	var x456 uint64
-	var x457 uint64
-	x456, x457 = bits.Sub64(x443, 0xffffffff00000000, uint64(p384Uint1(x455)))
-	var x458 uint64
-	var x459 uint64
-	x458, x459 = bits.Sub64(x445, 0xfffffffffffffffe, uint64(p384Uint1(x457)))
-	var x460 uint64
-	var x461 uint64
-	x460, x461 = bits.Sub64(x447, 0xffffffffffffffff, uint64(p384Uint1(x459)))
-	var x462 uint64
-	var x463 uint64
-	x462, x463 = bits.Sub64(x449, 0xffffffffffffffff, uint64(p384Uint1(x461)))
-	var x464 uint64
-	var x465 uint64
-	x464, x465 = bits.Sub64(x451, 0xffffffffffffffff, uint64(p384Uint1(x463)))
-	var x467 uint64
-	_, x467 = bits.Sub64(x453, uint64(0x0), uint64(p384Uint1(x465)))
-	var x468 uint64
-	p384CmovznzU64(&x468, p384Uint1(x467), x454, x441)
-	var x469 uint64
-	p384CmovznzU64(&x469, p384Uint1(x467), x456, x443)
-	var x470 uint64
-	p384CmovznzU64(&x470, p384Uint1(x467), x458, x445)
-	var x471 uint64
-	p384CmovznzU64(&x471, p384Uint1(x467), x460, x447)
-	var x472 uint64
-	p384CmovznzU64(&x472, p384Uint1(x467), x462, x449)
-	var x473 uint64
-	p384CmovznzU64(&x473, p384Uint1(x467), x464, x451)
-	out1[0] = x468
-	out1[1] = x469
-	out1[2] = x470
-	out1[3] = x471
-	out1[4] = x472
-	out1[5] = x473
-}
-
-// p384Add adds two field elements in the Montgomery domain.
-//
-// Preconditions:
-//   0 ≤ eval arg1 < m
-//   0 ≤ eval arg2 < m
-// Postconditions:
-//   eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) + eval (from_montgomery arg2)) mod m
-//   0 ≤ eval out1 < m
-//
-func p384Add(out1 *p384MontgomeryDomainFieldElement, arg1 *p384MontgomeryDomainFieldElement, arg2 *p384MontgomeryDomainFieldElement) {
-	var x1 uint64
-	var x2 uint64
-	x1, x2 = bits.Add64(arg1[0], arg2[0], uint64(0x0))
-	var x3 uint64
-	var x4 uint64
-	x3, x4 = bits.Add64(arg1[1], arg2[1], uint64(p384Uint1(x2)))
-	var x5 uint64
-	var x6 uint64
-	x5, x6 = bits.Add64(arg1[2], arg2[2], uint64(p384Uint1(x4)))
-	var x7 uint64
-	var x8 uint64
-	x7, x8 = bits.Add64(arg1[3], arg2[3], uint64(p384Uint1(x6)))
-	var x9 uint64
-	var x10 uint64
-	x9, x10 = bits.Add64(arg1[4], arg2[4], uint64(p384Uint1(x8)))
-	var x11 uint64
-	var x12 uint64
-	x11, x12 = bits.Add64(arg1[5], arg2[5], uint64(p384Uint1(x10)))
-	var x13 uint64
-	var x14 uint64
-	x13, x14 = bits.Sub64(x1, 0xffffffff, uint64(0x0))
-	var x15 uint64
-	var x16 uint64
-	x15, x16 = bits.Sub64(x3, 0xffffffff00000000, uint64(p384Uint1(x14)))
-	var x17 uint64
-	var x18 uint64
-	x17, x18 = bits.Sub64(x5, 0xfffffffffffffffe, uint64(p384Uint1(x16)))
-	var x19 uint64
-	var x20 uint64
-	x19, x20 = bits.Sub64(x7, 0xffffffffffffffff, uint64(p384Uint1(x18)))
-	var x21 uint64
-	var x22 uint64
-	x21, x22 = bits.Sub64(x9, 0xffffffffffffffff, uint64(p384Uint1(x20)))
-	var x23 uint64
-	var x24 uint64
-	x23, x24 = bits.Sub64(x11, 0xffffffffffffffff, uint64(p384Uint1(x22)))
-	var x26 uint64
-	_, x26 = bits.Sub64(uint64(p384Uint1(x12)), uint64(0x0), uint64(p384Uint1(x24)))
-	var x27 uint64
-	p384CmovznzU64(&x27, p384Uint1(x26), x13, x1)
-	var x28 uint64
-	p384CmovznzU64(&x28, p384Uint1(x26), x15, x3)
-	var x29 uint64
-	p384CmovznzU64(&x29, p384Uint1(x26), x17, x5)
-	var x30 uint64
-	p384CmovznzU64(&x30, p384Uint1(x26), x19, x7)
-	var x31 uint64
-	p384CmovznzU64(&x31, p384Uint1(x26), x21, x9)
-	var x32 uint64
-	p384CmovznzU64(&x32, p384Uint1(x26), x23, x11)
-	out1[0] = x27
-	out1[1] = x28
-	out1[2] = x29
-	out1[3] = x30
-	out1[4] = x31
-	out1[5] = x32
-}
-
-// p384Sub subtracts two field elements in the Montgomery domain.
-//
-// Preconditions:
-//   0 ≤ eval arg1 < m
-//   0 ≤ eval arg2 < m
-// Postconditions:
-//   eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) - eval (from_montgomery arg2)) mod m
-//   0 ≤ eval out1 < m
-//
-func p384Sub(out1 *p384MontgomeryDomainFieldElement, arg1 *p384MontgomeryDomainFieldElement, arg2 *p384MontgomeryDomainFieldElement) {
-	var x1 uint64
-	var x2 uint64
-	x1, x2 = bits.Sub64(arg1[0], arg2[0], uint64(0x0))
-	var x3 uint64
-	var x4 uint64
-	x3, x4 = bits.Sub64(arg1[1], arg2[1], uint64(p384Uint1(x2)))
-	var x5 uint64
-	var x6 uint64
-	x5, x6 = bits.Sub64(arg1[2], arg2[2], uint64(p384Uint1(x4)))
-	var x7 uint64
-	var x8 uint64
-	x7, x8 = bits.Sub64(arg1[3], arg2[3], uint64(p384Uint1(x6)))
-	var x9 uint64
-	var x10 uint64
-	x9, x10 = bits.Sub64(arg1[4], arg2[4], uint64(p384Uint1(x8)))
-	var x11 uint64
-	var x12 uint64
-	x11, x12 = bits.Sub64(arg1[5], arg2[5], uint64(p384Uint1(x10)))
-	var x13 uint64
-	p384CmovznzU64(&x13, p384Uint1(x12), uint64(0x0), 0xffffffffffffffff)
-	var x14 uint64
-	var x15 uint64
-	x14, x15 = bits.Add64(x1, (x13 & 0xffffffff), uint64(0x0))
-	var x16 uint64
-	var x17 uint64
-	x16, x17 = bits.Add64(x3, (x13 & 0xffffffff00000000), uint64(p384Uint1(x15)))
-	var x18 uint64
-	var x19 uint64
-	x18, x19 = bits.Add64(x5, (x13 & 0xfffffffffffffffe), uint64(p384Uint1(x17)))
-	var x20 uint64
-	var x21 uint64
-	x20, x21 = bits.Add64(x7, x13, uint64(p384Uint1(x19)))
-	var x22 uint64
-	var x23 uint64
-	x22, x23 = bits.Add64(x9, x13, uint64(p384Uint1(x21)))
-	var x24 uint64
-	x24, _ = bits.Add64(x11, x13, uint64(p384Uint1(x23)))
-	out1[0] = x14
-	out1[1] = x16
-	out1[2] = x18
-	out1[3] = x20
-	out1[4] = x22
-	out1[5] = x24
-}
-
-// p384SetOne returns the field element one in the Montgomery domain.
-//
-// Postconditions:
-//   eval (from_montgomery out1) mod m = 1 mod m
-//   0 ≤ eval out1 < m
-//
-func p384SetOne(out1 *p384MontgomeryDomainFieldElement) {
-	out1[0] = 0xffffffff00000001
-	out1[1] = 0xffffffff
-	out1[2] = uint64(0x1)
-	out1[3] = uint64(0x0)
-	out1[4] = uint64(0x0)
-	out1[5] = uint64(0x0)
-}
-
-// p384FromMontgomery translates a field element out of the Montgomery domain.
-//
-// Preconditions:
-//   0 ≤ eval arg1 < m
-// Postconditions:
-//   eval out1 mod m = (eval arg1 * ((2^64)⁻¹ mod m)^6) mod m
-//   0 ≤ eval out1 < m
-//
-func p384FromMontgomery(out1 *p384NonMontgomeryDomainFieldElement, arg1 *p384MontgomeryDomainFieldElement) {
-	x1 := arg1[0]
-	var x2 uint64
-	_, x2 = bits.Mul64(x1, 0x100000001)
-	var x4 uint64
-	var x5 uint64
-	x5, x4 = bits.Mul64(x2, 0xffffffffffffffff)
-	var x6 uint64
-	var x7 uint64
-	x7, x6 = bits.Mul64(x2, 0xffffffffffffffff)
-	var x8 uint64
-	var x9 uint64
-	x9, x8 = bits.Mul64(x2, 0xffffffffffffffff)
-	var x10 uint64
-	var x11 uint64
-	x11, x10 = bits.Mul64(x2, 0xfffffffffffffffe)
-	var x12 uint64
-	var x13 uint64
-	x13, x12 = bits.Mul64(x2, 0xffffffff00000000)
-	var x14 uint64
-	var x15 uint64
-	x15, x14 = bits.Mul64(x2, 0xffffffff)
-	var x16 uint64
-	var x17 uint64
-	x16, x17 = bits.Add64(x15, x12, uint64(0x0))
-	var x18 uint64
-	var x19 uint64
-	x18, x19 = bits.Add64(x13, x10, uint64(p384Uint1(x17)))
-	var x20 uint64
-	var x21 uint64
-	x20, x21 = bits.Add64(x11, x8, uint64(p384Uint1(x19)))
-	var x22 uint64
-	var x23 uint64
-	x22, x23 = bits.Add64(x9, x6, uint64(p384Uint1(x21)))
-	var x24 uint64
-	var x25 uint64
-	x24, x25 = bits.Add64(x7, x4, uint64(p384Uint1(x23)))
-	var x27 uint64
-	_, x27 = bits.Add64(x1, x14, uint64(0x0))
-	var x28 uint64
-	var x29 uint64
-	x28, x29 = bits.Add64(uint64(0x0), x16, uint64(p384Uint1(x27)))
-	var x30 uint64
-	var x31 uint64
-	x30, x31 = bits.Add64(uint64(0x0), x18, uint64(p384Uint1(x29)))
-	var x32 uint64
-	var x33 uint64
-	x32, x33 = bits.Add64(uint64(0x0), x20, uint64(p384Uint1(x31)))
-	var x34 uint64
-	var x35 uint64
-	x34, x35 = bits.Add64(uint64(0x0), x22, uint64(p384Uint1(x33)))
-	var x36 uint64
-	var x37 uint64
-	x36, x37 = bits.Add64(uint64(0x0), x24, uint64(p384Uint1(x35)))
-	var x38 uint64
-	var x39 uint64
-	x38, x39 = bits.Add64(uint64(0x0), (uint64(p384Uint1(x25)) + x5), uint64(p384Uint1(x37)))
-	var x40 uint64
-	var x41 uint64
-	x40, x41 = bits.Add64(x28, arg1[1], uint64(0x0))
-	var x42 uint64
-	var x43 uint64
-	x42, x43 = bits.Add64(x30, uint64(0x0), uint64(p384Uint1(x41)))
-	var x44 uint64
-	var x45 uint64
-	x44, x45 = bits.Add64(x32, uint64(0x0), uint64(p384Uint1(x43)))
-	var x46 uint64
-	var x47 uint64
-	x46, x47 = bits.Add64(x34, uint64(0x0), uint64(p384Uint1(x45)))
-	var x48 uint64
-	var x49 uint64
-	x48, x49 = bits.Add64(x36, uint64(0x0), uint64(p384Uint1(x47)))
-	var x50 uint64
-	var x51 uint64
-	x50, x51 = bits.Add64(x38, uint64(0x0), uint64(p384Uint1(x49)))
-	var x52 uint64
-	_, x52 = bits.Mul64(x40, 0x100000001)
-	var x54 uint64
-	var x55 uint64
-	x55, x54 = bits.Mul64(x52, 0xffffffffffffffff)
-	var x56 uint64
-	var x57 uint64
-	x57, x56 = bits.Mul64(x52, 0xffffffffffffffff)
-	var x58 uint64
-	var x59 uint64
-	x59, x58 = bits.Mul64(x52, 0xffffffffffffffff)
-	var x60 uint64
-	var x61 uint64
-	x61, x60 = bits.Mul64(x52, 0xfffffffffffffffe)
-	var x62 uint64
-	var x63 uint64
-	x63, x62 = bits.Mul64(x52, 0xffffffff00000000)
-	var x64 uint64
-	var x65 uint64
-	x65, x64 = bits.Mul64(x52, 0xffffffff)
-	var x66 uint64
-	var x67 uint64
-	x66, x67 = bits.Add64(x65, x62, uint64(0x0))
-	var x68 uint64
-	var x69 uint64
-	x68, x69 = bits.Add64(x63, x60, uint64(p384Uint1(x67)))
-	var x70 uint64
-	var x71 uint64
-	x70, x71 = bits.Add64(x61, x58, uint64(p384Uint1(x69)))
-	var x72 uint64
-	var x73 uint64
-	x72, x73 = bits.Add64(x59, x56, uint64(p384Uint1(x71)))
-	var x74 uint64
-	var x75 uint64
-	x74, x75 = bits.Add64(x57, x54, uint64(p384Uint1(x73)))
-	var x77 uint64
-	_, x77 = bits.Add64(x40, x64, uint64(0x0))
-	var x78 uint64
-	var x79 uint64
-	x78, x79 = bits.Add64(x42, x66, uint64(p384Uint1(x77)))
-	var x80 uint64
-	var x81 uint64
-	x80, x81 = bits.Add64(x44, x68, uint64(p384Uint1(x79)))
-	var x82 uint64
-	var x83 uint64
-	x82, x83 = bits.Add64(x46, x70, uint64(p384Uint1(x81)))
-	var x84 uint64
-	var x85 uint64
-	x84, x85 = bits.Add64(x48, x72, uint64(p384Uint1(x83)))
-	var x86 uint64
-	var x87 uint64
-	x86, x87 = bits.Add64(x50, x74, uint64(p384Uint1(x85)))
-	var x88 uint64
-	var x89 uint64
-	x88, x89 = bits.Add64((uint64(p384Uint1(x51)) + uint64(p384Uint1(x39))), (uint64(p384Uint1(x75)) + x55), uint64(p384Uint1(x87)))
-	var x90 uint64
-	var x91 uint64
-	x90, x91 = bits.Add64(x78, arg1[2], uint64(0x0))
-	var x92 uint64
-	var x93 uint64
-	x92, x93 = bits.Add64(x80, uint64(0x0), uint64(p384Uint1(x91)))
-	var x94 uint64
-	var x95 uint64
-	x94, x95 = bits.Add64(x82, uint64(0x0), uint64(p384Uint1(x93)))
-	var x96 uint64
-	var x97 uint64
-	x96, x97 = bits.Add64(x84, uint64(0x0), uint64(p384Uint1(x95)))
-	var x98 uint64
-	var x99 uint64
-	x98, x99 = bits.Add64(x86, uint64(0x0), uint64(p384Uint1(x97)))
-	var x100 uint64
-	var x101 uint64
-	x100, x101 = bits.Add64(x88, uint64(0x0), uint64(p384Uint1(x99)))
-	var x102 uint64
-	_, x102 = bits.Mul64(x90, 0x100000001)
-	var x104 uint64
-	var x105 uint64
-	x105, x104 = bits.Mul64(x102, 0xffffffffffffffff)
-	var x106 uint64
-	var x107 uint64
-	x107, x106 = bits.Mul64(x102, 0xffffffffffffffff)
-	var x108 uint64
-	var x109 uint64
-	x109, x108 = bits.Mul64(x102, 0xffffffffffffffff)
-	var x110 uint64
-	var x111 uint64
-	x111, x110 = bits.Mul64(x102, 0xfffffffffffffffe)
-	var x112 uint64
-	var x113 uint64
-	x113, x112 = bits.Mul64(x102, 0xffffffff00000000)
-	var x114 uint64
-	var x115 uint64
-	x115, x114 = bits.Mul64(x102, 0xffffffff)
-	var x116 uint64
-	var x117 uint64
-	x116, x117 = bits.Add64(x115, x112, uint64(0x0))
-	var x118 uint64
-	var x119 uint64
-	x118, x119 = bits.Add64(x113, x110, uint64(p384Uint1(x117)))
-	var x120 uint64
-	var x121 uint64
-	x120, x121 = bits.Add64(x111, x108, uint64(p384Uint1(x119)))
-	var x122 uint64
-	var x123 uint64
-	x122, x123 = bits.Add64(x109, x106, uint64(p384Uint1(x121)))
-	var x124 uint64
-	var x125 uint64
-	x124, x125 = bits.Add64(x107, x104, uint64(p384Uint1(x123)))
-	var x127 uint64
-	_, x127 = bits.Add64(x90, x114, uint64(0x0))
-	var x128 uint64
-	var x129 uint64
-	x128, x129 = bits.Add64(x92, x116, uint64(p384Uint1(x127)))
-	var x130 uint64
-	var x131 uint64
-	x130, x131 = bits.Add64(x94, x118, uint64(p384Uint1(x129)))
-	var x132 uint64
-	var x133 uint64
-	x132, x133 = bits.Add64(x96, x120, uint64(p384Uint1(x131)))
-	var x134 uint64
-	var x135 uint64
-	x134, x135 = bits.Add64(x98, x122, uint64(p384Uint1(x133)))
-	var x136 uint64
-	var x137 uint64
-	x136, x137 = bits.Add64(x100, x124, uint64(p384Uint1(x135)))
-	var x138 uint64
-	var x139 uint64
-	x138, x139 = bits.Add64((uint64(p384Uint1(x101)) + uint64(p384Uint1(x89))), (uint64(p384Uint1(x125)) + x105), uint64(p384Uint1(x137)))
-	var x140 uint64
-	var x141 uint64
-	x140, x141 = bits.Add64(x128, arg1[3], uint64(0x0))
-	var x142 uint64
-	var x143 uint64
-	x142, x143 = bits.Add64(x130, uint64(0x0), uint64(p384Uint1(x141)))
-	var x144 uint64
-	var x145 uint64
-	x144, x145 = bits.Add64(x132, uint64(0x0), uint64(p384Uint1(x143)))
-	var x146 uint64
-	var x147 uint64
-	x146, x147 = bits.Add64(x134, uint64(0x0), uint64(p384Uint1(x145)))
-	var x148 uint64
-	var x149 uint64
-	x148, x149 = bits.Add64(x136, uint64(0x0), uint64(p384Uint1(x147)))
-	var x150 uint64
-	var x151 uint64
-	x150, x151 = bits.Add64(x138, uint64(0x0), uint64(p384Uint1(x149)))
-	var x152 uint64
-	_, x152 = bits.Mul64(x140, 0x100000001)
-	var x154 uint64
-	var x155 uint64
-	x155, x154 = bits.Mul64(x152, 0xffffffffffffffff)
-	var x156 uint64
-	var x157 uint64
-	x157, x156 = bits.Mul64(x152, 0xffffffffffffffff)
-	var x158 uint64
-	var x159 uint64
-	x159, x158 = bits.Mul64(x152, 0xffffffffffffffff)
-	var x160 uint64
-	var x161 uint64
-	x161, x160 = bits.Mul64(x152, 0xfffffffffffffffe)
-	var x162 uint64
-	var x163 uint64
-	x163, x162 = bits.Mul64(x152, 0xffffffff00000000)
-	var x164 uint64
-	var x165 uint64
-	x165, x164 = bits.Mul64(x152, 0xffffffff)
-	var x166 uint64
-	var x167 uint64
-	x166, x167 = bits.Add64(x165, x162, uint64(0x0))
-	var x168 uint64
-	var x169 uint64
-	x168, x169 = bits.Add64(x163, x160, uint64(p384Uint1(x167)))
-	var x170 uint64
-	var x171 uint64
-	x170, x171 = bits.Add64(x161, x158, uint64(p384Uint1(x169)))
-	var x172 uint64
-	var x173 uint64
-	x172, x173 = bits.Add64(x159, x156, uint64(p384Uint1(x171)))
-	var x174 uint64
-	var x175 uint64
-	x174, x175 = bits.Add64(x157, x154, uint64(p384Uint1(x173)))
-	var x177 uint64
-	_, x177 = bits.Add64(x140, x164, uint64(0x0))
-	var x178 uint64
-	var x179 uint64
-	x178, x179 = bits.Add64(x142, x166, uint64(p384Uint1(x177)))
-	var x180 uint64
-	var x181 uint64
-	x180, x181 = bits.Add64(x144, x168, uint64(p384Uint1(x179)))
-	var x182 uint64
-	var x183 uint64
-	x182, x183 = bits.Add64(x146, x170, uint64(p384Uint1(x181)))
-	var x184 uint64
-	var x185 uint64
-	x184, x185 = bits.Add64(x148, x172, uint64(p384Uint1(x183)))
-	var x186 uint64
-	var x187 uint64
-	x186, x187 = bits.Add64(x150, x174, uint64(p384Uint1(x185)))
-	var x188 uint64
-	var x189 uint64
-	x188, x189 = bits.Add64((uint64(p384Uint1(x151)) + uint64(p384Uint1(x139))), (uint64(p384Uint1(x175)) + x155), uint64(p384Uint1(x187)))
-	var x190 uint64
-	var x191 uint64
-	x190, x191 = bits.Add64(x178, arg1[4], uint64(0x0))
-	var x192 uint64
-	var x193 uint64
-	x192, x193 = bits.Add64(x180, uint64(0x0), uint64(p384Uint1(x191)))
-	var x194 uint64
-	var x195 uint64
-	x194, x195 = bits.Add64(x182, uint64(0x0), uint64(p384Uint1(x193)))
-	var x196 uint64
-	var x197 uint64
-	x196, x197 = bits.Add64(x184, uint64(0x0), uint64(p384Uint1(x195)))
-	var x198 uint64
-	var x199 uint64
-	x198, x199 = bits.Add64(x186, uint64(0x0), uint64(p384Uint1(x197)))
-	var x200 uint64
-	var x201 uint64
-	x200, x201 = bits.Add64(x188, uint64(0x0), uint64(p384Uint1(x199)))
-	var x202 uint64
-	_, x202 = bits.Mul64(x190, 0x100000001)
-	var x204 uint64
-	var x205 uint64
-	x205, x204 = bits.Mul64(x202, 0xffffffffffffffff)
-	var x206 uint64
-	var x207 uint64
-	x207, x206 = bits.Mul64(x202, 0xffffffffffffffff)
-	var x208 uint64
-	var x209 uint64
-	x209, x208 = bits.Mul64(x202, 0xffffffffffffffff)
-	var x210 uint64
-	var x211 uint64
-	x211, x210 = bits.Mul64(x202, 0xfffffffffffffffe)
-	var x212 uint64
-	var x213 uint64
-	x213, x212 = bits.Mul64(x202, 0xffffffff00000000)
-	var x214 uint64
-	var x215 uint64
-	x215, x214 = bits.Mul64(x202, 0xffffffff)
-	var x216 uint64
-	var x217 uint64
-	x216, x217 = bits.Add64(x215, x212, uint64(0x0))
-	var x218 uint64
-	var x219 uint64
-	x218, x219 = bits.Add64(x213, x210, uint64(p384Uint1(x217)))
-	var x220 uint64
-	var x221 uint64
-	x220, x221 = bits.Add64(x211, x208, uint64(p384Uint1(x219)))
-	var x222 uint64
-	var x223 uint64
-	x222, x223 = bits.Add64(x209, x206, uint64(p384Uint1(x221)))
-	var x224 uint64
-	var x225 uint64
-	x224, x225 = bits.Add64(x207, x204, uint64(p384Uint1(x223)))
-	var x227 uint64
-	_, x227 = bits.Add64(x190, x214, uint64(0x0))
-	var x228 uint64
-	var x229 uint64
-	x228, x229 = bits.Add64(x192, x216, uint64(p384Uint1(x227)))
-	var x230 uint64
-	var x231 uint64
-	x230, x231 = bits.Add64(x194, x218, uint64(p384Uint1(x229)))
-	var x232 uint64
-	var x233 uint64
-	x232, x233 = bits.Add64(x196, x220, uint64(p384Uint1(x231)))
-	var x234 uint64
-	var x235 uint64
-	x234, x235 = bits.Add64(x198, x222, uint64(p384Uint1(x233)))
-	var x236 uint64
-	var x237 uint64
-	x236, x237 = bits.Add64(x200, x224, uint64(p384Uint1(x235)))
-	var x238 uint64
-	var x239 uint64
-	x238, x239 = bits.Add64((uint64(p384Uint1(x201)) + uint64(p384Uint1(x189))), (uint64(p384Uint1(x225)) + x205), uint64(p384Uint1(x237)))
-	var x240 uint64
-	var x241 uint64
-	x240, x241 = bits.Add64(x228, arg1[5], uint64(0x0))
-	var x242 uint64
-	var x243 uint64
-	x242, x243 = bits.Add64(x230, uint64(0x0), uint64(p384Uint1(x241)))
-	var x244 uint64
-	var x245 uint64
-	x244, x245 = bits.Add64(x232, uint64(0x0), uint64(p384Uint1(x243)))
-	var x246 uint64
-	var x247 uint64
-	x246, x247 = bits.Add64(x234, uint64(0x0), uint64(p384Uint1(x245)))
-	var x248 uint64
-	var x249 uint64
-	x248, x249 = bits.Add64(x236, uint64(0x0), uint64(p384Uint1(x247)))
-	var x250 uint64
-	var x251 uint64
-	x250, x251 = bits.Add64(x238, uint64(0x0), uint64(p384Uint1(x249)))
-	var x252 uint64
-	_, x252 = bits.Mul64(x240, 0x100000001)
-	var x254 uint64
-	var x255 uint64
-	x255, x254 = bits.Mul64(x252, 0xffffffffffffffff)
-	var x256 uint64
-	var x257 uint64
-	x257, x256 = bits.Mul64(x252, 0xffffffffffffffff)
-	var x258 uint64
-	var x259 uint64
-	x259, x258 = bits.Mul64(x252, 0xffffffffffffffff)
-	var x260 uint64
-	var x261 uint64
-	x261, x260 = bits.Mul64(x252, 0xfffffffffffffffe)
-	var x262 uint64
-	var x263 uint64
-	x263, x262 = bits.Mul64(x252, 0xffffffff00000000)
-	var x264 uint64
-	var x265 uint64
-	x265, x264 = bits.Mul64(x252, 0xffffffff)
-	var x266 uint64
-	var x267 uint64
-	x266, x267 = bits.Add64(x265, x262, uint64(0x0))
-	var x268 uint64
-	var x269 uint64
-	x268, x269 = bits.Add64(x263, x260, uint64(p384Uint1(x267)))
-	var x270 uint64
-	var x271 uint64
-	x270, x271 = bits.Add64(x261, x258, uint64(p384Uint1(x269)))
-	var x272 uint64
-	var x273 uint64
-	x272, x273 = bits.Add64(x259, x256, uint64(p384Uint1(x271)))
-	var x274 uint64
-	var x275 uint64
-	x274, x275 = bits.Add64(x257, x254, uint64(p384Uint1(x273)))
-	var x277 uint64
-	_, x277 = bits.Add64(x240, x264, uint64(0x0))
-	var x278 uint64
-	var x279 uint64
-	x278, x279 = bits.Add64(x242, x266, uint64(p384Uint1(x277)))
-	var x280 uint64
-	var x281 uint64
-	x280, x281 = bits.Add64(x244, x268, uint64(p384Uint1(x279)))
-	var x282 uint64
-	var x283 uint64
-	x282, x283 = bits.Add64(x246, x270, uint64(p384Uint1(x281)))
-	var x284 uint64
-	var x285 uint64
-	x284, x285 = bits.Add64(x248, x272, uint64(p384Uint1(x283)))
-	var x286 uint64
-	var x287 uint64
-	x286, x287 = bits.Add64(x250, x274, uint64(p384Uint1(x285)))
-	var x288 uint64
-	var x289 uint64
-	x288, x289 = bits.Add64((uint64(p384Uint1(x251)) + uint64(p384Uint1(x239))), (uint64(p384Uint1(x275)) + x255), uint64(p384Uint1(x287)))
-	var x290 uint64
-	var x291 uint64
-	x290, x291 = bits.Sub64(x278, 0xffffffff, uint64(0x0))
-	var x292 uint64
-	var x293 uint64
-	x292, x293 = bits.Sub64(x280, 0xffffffff00000000, uint64(p384Uint1(x291)))
-	var x294 uint64
-	var x295 uint64
-	x294, x295 = bits.Sub64(x282, 0xfffffffffffffffe, uint64(p384Uint1(x293)))
-	var x296 uint64
-	var x297 uint64
-	x296, x297 = bits.Sub64(x284, 0xffffffffffffffff, uint64(p384Uint1(x295)))
-	var x298 uint64
-	var x299 uint64
-	x298, x299 = bits.Sub64(x286, 0xffffffffffffffff, uint64(p384Uint1(x297)))
-	var x300 uint64
-	var x301 uint64
-	x300, x301 = bits.Sub64(x288, 0xffffffffffffffff, uint64(p384Uint1(x299)))
-	var x303 uint64
-	_, x303 = bits.Sub64(uint64(p384Uint1(x289)), uint64(0x0), uint64(p384Uint1(x301)))
-	var x304 uint64
-	p384CmovznzU64(&x304, p384Uint1(x303), x290, x278)
-	var x305 uint64
-	p384CmovznzU64(&x305, p384Uint1(x303), x292, x280)
-	var x306 uint64
-	p384CmovznzU64(&x306, p384Uint1(x303), x294, x282)
-	var x307 uint64
-	p384CmovznzU64(&x307, p384Uint1(x303), x296, x284)
-	var x308 uint64
-	p384CmovznzU64(&x308, p384Uint1(x303), x298, x286)
-	var x309 uint64
-	p384CmovznzU64(&x309, p384Uint1(x303), x300, x288)
-	out1[0] = x304
-	out1[1] = x305
-	out1[2] = x306
-	out1[3] = x307
-	out1[4] = x308
-	out1[5] = x309
-}
-
-// p384ToMontgomery translates a field element into the Montgomery domain.
-//
-// Preconditions:
-//   0 ≤ eval arg1 < m
-// Postconditions:
-//   eval (from_montgomery out1) mod m = eval arg1 mod m
-//   0 ≤ eval out1 < m
-//
-func p384ToMontgomery(out1 *p384MontgomeryDomainFieldElement, arg1 *p384NonMontgomeryDomainFieldElement) {
-	x1 := arg1[1]
-	x2 := arg1[2]
-	x3 := arg1[3]
-	x4 := arg1[4]
-	x5 := arg1[5]
-	x6 := arg1[0]
-	var x7 uint64
-	var x8 uint64
-	x8, x7 = bits.Mul64(x6, 0x200000000)
-	var x9 uint64
-	var x10 uint64
-	x10, x9 = bits.Mul64(x6, 0xfffffffe00000000)
-	var x11 uint64
-	var x12 uint64
-	x12, x11 = bits.Mul64(x6, 0x200000000)
-	var x13 uint64
-	var x14 uint64
-	x14, x13 = bits.Mul64(x6, 0xfffffffe00000001)
-	var x15 uint64
-	var x16 uint64
-	x15, x16 = bits.Add64(x14, x11, uint64(0x0))
-	var x17 uint64
-	var x18 uint64
-	x17, x18 = bits.Add64(x12, x9, uint64(p384Uint1(x16)))
-	var x19 uint64
-	var x20 uint64
-	x19, x20 = bits.Add64(x10, x7, uint64(p384Uint1(x18)))
-	var x21 uint64
-	var x22 uint64
-	x21, x22 = bits.Add64(x8, x6, uint64(p384Uint1(x20)))
-	var x23 uint64
-	_, x23 = bits.Mul64(x13, 0x100000001)
-	var x25 uint64
-	var x26 uint64
-	x26, x25 = bits.Mul64(x23, 0xffffffffffffffff)
-	var x27 uint64
-	var x28 uint64
-	x28, x27 = bits.Mul64(x23, 0xffffffffffffffff)
-	var x29 uint64
-	var x30 uint64
-	x30, x29 = bits.Mul64(x23, 0xffffffffffffffff)
-	var x31 uint64
-	var x32 uint64
-	x32, x31 = bits.Mul64(x23, 0xfffffffffffffffe)
-	var x33 uint64
-	var x34 uint64
-	x34, x33 = bits.Mul64(x23, 0xffffffff00000000)
-	var x35 uint64
-	var x36 uint64
-	x36, x35 = bits.Mul64(x23, 0xffffffff)
-	var x37 uint64
-	var x38 uint64
-	x37, x38 = bits.Add64(x36, x33, uint64(0x0))
-	var x39 uint64
-	var x40 uint64
-	x39, x40 = bits.Add64(x34, x31, uint64(p384Uint1(x38)))
-	var x41 uint64
-	var x42 uint64
-	x41, x42 = bits.Add64(x32, x29, uint64(p384Uint1(x40)))
-	var x43 uint64
-	var x44 uint64
-	x43, x44 = bits.Add64(x30, x27, uint64(p384Uint1(x42)))
-	var x45 uint64
-	var x46 uint64
-	x45, x46 = bits.Add64(x28, x25, uint64(p384Uint1(x44)))
-	var x48 uint64
-	_, x48 = bits.Add64(x13, x35, uint64(0x0))
-	var x49 uint64
-	var x50 uint64
-	x49, x50 = bits.Add64(x15, x37, uint64(p384Uint1(x48)))
-	var x51 uint64
-	var x52 uint64
-	x51, x52 = bits.Add64(x17, x39, uint64(p384Uint1(x50)))
-	var x53 uint64
-	var x54 uint64
-	x53, x54 = bits.Add64(x19, x41, uint64(p384Uint1(x52)))
-	var x55 uint64
-	var x56 uint64
-	x55, x56 = bits.Add64(x21, x43, uint64(p384Uint1(x54)))
-	var x57 uint64
-	var x58 uint64
-	x57, x58 = bits.Add64(uint64(p384Uint1(x22)), x45, uint64(p384Uint1(x56)))
-	var x59 uint64
-	var x60 uint64
-	x59, x60 = bits.Add64(uint64(0x0), (uint64(p384Uint1(x46)) + x26), uint64(p384Uint1(x58)))
-	var x61 uint64
-	var x62 uint64
-	x62, x61 = bits.Mul64(x1, 0x200000000)
-	var x63 uint64
-	var x64 uint64
-	x64, x63 = bits.Mul64(x1, 0xfffffffe00000000)
-	var x65 uint64
-	var x66 uint64
-	x66, x65 = bits.Mul64(x1, 0x200000000)
-	var x67 uint64
-	var x68 uint64
-	x68, x67 = bits.Mul64(x1, 0xfffffffe00000001)
-	var x69 uint64
-	var x70 uint64
-	x69, x70 = bits.Add64(x68, x65, uint64(0x0))
-	var x71 uint64
-	var x72 uint64
-	x71, x72 = bits.Add64(x66, x63, uint64(p384Uint1(x70)))
-	var x73 uint64
-	var x74 uint64
-	x73, x74 = bits.Add64(x64, x61, uint64(p384Uint1(x72)))
-	var x75 uint64
-	var x76 uint64
-	x75, x76 = bits.Add64(x62, x1, uint64(p384Uint1(x74)))
-	var x77 uint64
-	var x78 uint64
-	x77, x78 = bits.Add64(x49, x67, uint64(0x0))
-	var x79 uint64
-	var x80 uint64
-	x79, x80 = bits.Add64(x51, x69, uint64(p384Uint1(x78)))
-	var x81 uint64
-	var x82 uint64
-	x81, x82 = bits.Add64(x53, x71, uint64(p384Uint1(x80)))
-	var x83 uint64
-	var x84 uint64
-	x83, x84 = bits.Add64(x55, x73, uint64(p384Uint1(x82)))
-	var x85 uint64
-	var x86 uint64
-	x85, x86 = bits.Add64(x57, x75, uint64(p384Uint1(x84)))
-	var x87 uint64
-	var x88 uint64
-	x87, x88 = bits.Add64(x59, uint64(p384Uint1(x76)), uint64(p384Uint1(x86)))
-	var x89 uint64
-	_, x89 = bits.Mul64(x77, 0x100000001)
-	var x91 uint64
-	var x92 uint64
-	x92, x91 = bits.Mul64(x89, 0xffffffffffffffff)
-	var x93 uint64
-	var x94 uint64
-	x94, x93 = bits.Mul64(x89, 0xffffffffffffffff)
-	var x95 uint64
-	var x96 uint64
-	x96, x95 = bits.Mul64(x89, 0xffffffffffffffff)
-	var x97 uint64
-	var x98 uint64
-	x98, x97 = bits.Mul64(x89, 0xfffffffffffffffe)
-	var x99 uint64
-	var x100 uint64
-	x100, x99 = bits.Mul64(x89, 0xffffffff00000000)
-	var x101 uint64
-	var x102 uint64
-	x102, x101 = bits.Mul64(x89, 0xffffffff)
-	var x103 uint64
-	var x104 uint64
-	x103, x104 = bits.Add64(x102, x99, uint64(0x0))
-	var x105 uint64
-	var x106 uint64
-	x105, x106 = bits.Add64(x100, x97, uint64(p384Uint1(x104)))
-	var x107 uint64
-	var x108 uint64
-	x107, x108 = bits.Add64(x98, x95, uint64(p384Uint1(x106)))
-	var x109 uint64
-	var x110 uint64
-	x109, x110 = bits.Add64(x96, x93, uint64(p384Uint1(x108)))
-	var x111 uint64
-	var x112 uint64
-	x111, x112 = bits.Add64(x94, x91, uint64(p384Uint1(x110)))
-	var x114 uint64
-	_, x114 = bits.Add64(x77, x101, uint64(0x0))
-	var x115 uint64
-	var x116 uint64
-	x115, x116 = bits.Add64(x79, x103, uint64(p384Uint1(x114)))
-	var x117 uint64
-	var x118 uint64
-	x117, x118 = bits.Add64(x81, x105, uint64(p384Uint1(x116)))
-	var x119 uint64
-	var x120 uint64
-	x119, x120 = bits.Add64(x83, x107, uint64(p384Uint1(x118)))
-	var x121 uint64
-	var x122 uint64
-	x121, x122 = bits.Add64(x85, x109, uint64(p384Uint1(x120)))
-	var x123 uint64
-	var x124 uint64
-	x123, x124 = bits.Add64(x87, x111, uint64(p384Uint1(x122)))
-	var x125 uint64
-	var x126 uint64
-	x125, x126 = bits.Add64((uint64(p384Uint1(x88)) + uint64(p384Uint1(x60))), (uint64(p384Uint1(x112)) + x92), uint64(p384Uint1(x124)))
-	var x127 uint64
-	var x128 uint64
-	x128, x127 = bits.Mul64(x2, 0x200000000)
-	var x129 uint64
-	var x130 uint64
-	x130, x129 = bits.Mul64(x2, 0xfffffffe00000000)
-	var x131 uint64
-	var x132 uint64
-	x132, x131 = bits.Mul64(x2, 0x200000000)
-	var x133 uint64
-	var x134 uint64
-	x134, x133 = bits.Mul64(x2, 0xfffffffe00000001)
-	var x135 uint64
-	var x136 uint64
-	x135, x136 = bits.Add64(x134, x131, uint64(0x0))
-	var x137 uint64
-	var x138 uint64
-	x137, x138 = bits.Add64(x132, x129, uint64(p384Uint1(x136)))
-	var x139 uint64
-	var x140 uint64
-	x139, x140 = bits.Add64(x130, x127, uint64(p384Uint1(x138)))
-	var x141 uint64
-	var x142 uint64
-	x141, x142 = bits.Add64(x128, x2, uint64(p384Uint1(x140)))
-	var x143 uint64
-	var x144 uint64
-	x143, x144 = bits.Add64(x115, x133, uint64(0x0))
-	var x145 uint64
-	var x146 uint64
-	x145, x146 = bits.Add64(x117, x135, uint64(p384Uint1(x144)))
-	var x147 uint64
-	var x148 uint64
-	x147, x148 = bits.Add64(x119, x137, uint64(p384Uint1(x146)))
-	var x149 uint64
-	var x150 uint64
-	x149, x150 = bits.Add64(x121, x139, uint64(p384Uint1(x148)))
-	var x151 uint64
-	var x152 uint64
-	x151, x152 = bits.Add64(x123, x141, uint64(p384Uint1(x150)))
-	var x153 uint64
-	var x154 uint64
-	x153, x154 = bits.Add64(x125, uint64(p384Uint1(x142)), uint64(p384Uint1(x152)))
-	var x155 uint64
-	_, x155 = bits.Mul64(x143, 0x100000001)
-	var x157 uint64
-	var x158 uint64
-	x158, x157 = bits.Mul64(x155, 0xffffffffffffffff)
-	var x159 uint64
-	var x160 uint64
-	x160, x159 = bits.Mul64(x155, 0xffffffffffffffff)
-	var x161 uint64
-	var x162 uint64
-	x162, x161 = bits.Mul64(x155, 0xffffffffffffffff)
-	var x163 uint64
-	var x164 uint64
-	x164, x163 = bits.Mul64(x155, 0xfffffffffffffffe)
-	var x165 uint64
-	var x166 uint64
-	x166, x165 = bits.Mul64(x155, 0xffffffff00000000)
-	var x167 uint64
-	var x168 uint64
-	x168, x167 = bits.Mul64(x155, 0xffffffff)
-	var x169 uint64
-	var x170 uint64
-	x169, x170 = bits.Add64(x168, x165, uint64(0x0))
-	var x171 uint64
-	var x172 uint64
-	x171, x172 = bits.Add64(x166, x163, uint64(p384Uint1(x170)))
-	var x173 uint64
-	var x174 uint64
-	x173, x174 = bits.Add64(x164, x161, uint64(p384Uint1(x172)))
-	var x175 uint64
-	var x176 uint64
-	x175, x176 = bits.Add64(x162, x159, uint64(p384Uint1(x174)))
-	var x177 uint64
-	var x178 uint64
-	x177, x178 = bits.Add64(x160, x157, uint64(p384Uint1(x176)))
-	var x180 uint64
-	_, x180 = bits.Add64(x143, x167, uint64(0x0))
-	var x181 uint64
-	var x182 uint64
-	x181, x182 = bits.Add64(x145, x169, uint64(p384Uint1(x180)))
-	var x183 uint64
-	var x184 uint64
-	x183, x184 = bits.Add64(x147, x171, uint64(p384Uint1(x182)))
-	var x185 uint64
-	var x186 uint64
-	x185, x186 = bits.Add64(x149, x173, uint64(p384Uint1(x184)))
-	var x187 uint64
-	var x188 uint64
-	x187, x188 = bits.Add64(x151, x175, uint64(p384Uint1(x186)))
-	var x189 uint64
-	var x190 uint64
-	x189, x190 = bits.Add64(x153, x177, uint64(p384Uint1(x188)))
-	var x191 uint64
-	var x192 uint64
-	x191, x192 = bits.Add64((uint64(p384Uint1(x154)) + uint64(p384Uint1(x126))), (uint64(p384Uint1(x178)) + x158), uint64(p384Uint1(x190)))
-	var x193 uint64
-	var x194 uint64
-	x194, x193 = bits.Mul64(x3, 0x200000000)
-	var x195 uint64
-	var x196 uint64
-	x196, x195 = bits.Mul64(x3, 0xfffffffe00000000)
-	var x197 uint64
-	var x198 uint64
-	x198, x197 = bits.Mul64(x3, 0x200000000)
-	var x199 uint64
-	var x200 uint64
-	x200, x199 = bits.Mul64(x3, 0xfffffffe00000001)
-	var x201 uint64
-	var x202 uint64
-	x201, x202 = bits.Add64(x200, x197, uint64(0x0))
-	var x203 uint64
-	var x204 uint64
-	x203, x204 = bits.Add64(x198, x195, uint64(p384Uint1(x202)))
-	var x205 uint64
-	var x206 uint64
-	x205, x206 = bits.Add64(x196, x193, uint64(p384Uint1(x204)))
-	var x207 uint64
-	var x208 uint64
-	x207, x208 = bits.Add64(x194, x3, uint64(p384Uint1(x206)))
-	var x209 uint64
-	var x210 uint64
-	x209, x210 = bits.Add64(x181, x199, uint64(0x0))
-	var x211 uint64
-	var x212 uint64
-	x211, x212 = bits.Add64(x183, x201, uint64(p384Uint1(x210)))
-	var x213 uint64
-	var x214 uint64
-	x213, x214 = bits.Add64(x185, x203, uint64(p384Uint1(x212)))
-	var x215 uint64
-	var x216 uint64
-	x215, x216 = bits.Add64(x187, x205, uint64(p384Uint1(x214)))
-	var x217 uint64
-	var x218 uint64
-	x217, x218 = bits.Add64(x189, x207, uint64(p384Uint1(x216)))
-	var x219 uint64
-	var x220 uint64
-	x219, x220 = bits.Add64(x191, uint64(p384Uint1(x208)), uint64(p384Uint1(x218)))
-	var x221 uint64
-	_, x221 = bits.Mul64(x209, 0x100000001)
-	var x223 uint64
-	var x224 uint64
-	x224, x223 = bits.Mul64(x221, 0xffffffffffffffff)
-	var x225 uint64
-	var x226 uint64
-	x226, x225 = bits.Mul64(x221, 0xffffffffffffffff)
-	var x227 uint64
-	var x228 uint64
-	x228, x227 = bits.Mul64(x221, 0xffffffffffffffff)
-	var x229 uint64
-	var x230 uint64
-	x230, x229 = bits.Mul64(x221, 0xfffffffffffffffe)
-	var x231 uint64
-	var x232 uint64
-	x232, x231 = bits.Mul64(x221, 0xffffffff00000000)
-	var x233 uint64
-	var x234 uint64
-	x234, x233 = bits.Mul64(x221, 0xffffffff)
-	var x235 uint64
-	var x236 uint64
-	x235, x236 = bits.Add64(x234, x231, uint64(0x0))
-	var x237 uint64
-	var x238 uint64
-	x237, x238 = bits.Add64(x232, x229, uint64(p384Uint1(x236)))
-	var x239 uint64
-	var x240 uint64
-	x239, x240 = bits.Add64(x230, x227, uint64(p384Uint1(x238)))
-	var x241 uint64
-	var x242 uint64
-	x241, x242 = bits.Add64(x228, x225, uint64(p384Uint1(x240)))
-	var x243 uint64
-	var x244 uint64
-	x243, x244 = bits.Add64(x226, x223, uint64(p384Uint1(x242)))
-	var x246 uint64
-	_, x246 = bits.Add64(x209, x233, uint64(0x0))
-	var x247 uint64
-	var x248 uint64
-	x247, x248 = bits.Add64(x211, x235, uint64(p384Uint1(x246)))
-	var x249 uint64
-	var x250 uint64
-	x249, x250 = bits.Add64(x213, x237, uint64(p384Uint1(x248)))
-	var x251 uint64
-	var x252 uint64
-	x251, x252 = bits.Add64(x215, x239, uint64(p384Uint1(x250)))
-	var x253 uint64
-	var x254 uint64
-	x253, x254 = bits.Add64(x217, x241, uint64(p384Uint1(x252)))
-	var x255 uint64
-	var x256 uint64
-	x255, x256 = bits.Add64(x219, x243, uint64(p384Uint1(x254)))
-	var x257 uint64
-	var x258 uint64
-	x257, x258 = bits.Add64((uint64(p384Uint1(x220)) + uint64(p384Uint1(x192))), (uint64(p384Uint1(x244)) + x224), uint64(p384Uint1(x256)))
-	var x259 uint64
-	var x260 uint64
-	x260, x259 = bits.Mul64(x4, 0x200000000)
-	var x261 uint64
-	var x262 uint64
-	x262, x261 = bits.Mul64(x4, 0xfffffffe00000000)
-	var x263 uint64
-	var x264 uint64
-	x264, x263 = bits.Mul64(x4, 0x200000000)
-	var x265 uint64
-	var x266 uint64
-	x266, x265 = bits.Mul64(x4, 0xfffffffe00000001)
-	var x267 uint64
-	var x268 uint64
-	x267, x268 = bits.Add64(x266, x263, uint64(0x0))
-	var x269 uint64
-	var x270 uint64
-	x269, x270 = bits.Add64(x264, x261, uint64(p384Uint1(x268)))
-	var x271 uint64
-	var x272 uint64
-	x271, x272 = bits.Add64(x262, x259, uint64(p384Uint1(x270)))
-	var x273 uint64
-	var x274 uint64
-	x273, x274 = bits.Add64(x260, x4, uint64(p384Uint1(x272)))
-	var x275 uint64
-	var x276 uint64
-	x275, x276 = bits.Add64(x247, x265, uint64(0x0))
-	var x277 uint64
-	var x278 uint64
-	x277, x278 = bits.Add64(x249, x267, uint64(p384Uint1(x276)))
-	var x279 uint64
-	var x280 uint64
-	x279, x280 = bits.Add64(x251, x269, uint64(p384Uint1(x278)))
-	var x281 uint64
-	var x282 uint64
-	x281, x282 = bits.Add64(x253, x271, uint64(p384Uint1(x280)))
-	var x283 uint64
-	var x284 uint64
-	x283, x284 = bits.Add64(x255, x273, uint64(p384Uint1(x282)))
-	var x285 uint64
-	var x286 uint64
-	x285, x286 = bits.Add64(x257, uint64(p384Uint1(x274)), uint64(p384Uint1(x284)))
-	var x287 uint64
-	_, x287 = bits.Mul64(x275, 0x100000001)
-	var x289 uint64
-	var x290 uint64
-	x290, x289 = bits.Mul64(x287, 0xffffffffffffffff)
-	var x291 uint64
-	var x292 uint64
-	x292, x291 = bits.Mul64(x287, 0xffffffffffffffff)
-	var x293 uint64
-	var x294 uint64
-	x294, x293 = bits.Mul64(x287, 0xffffffffffffffff)
-	var x295 uint64
-	var x296 uint64
-	x296, x295 = bits.Mul64(x287, 0xfffffffffffffffe)
-	var x297 uint64
-	var x298 uint64
-	x298, x297 = bits.Mul64(x287, 0xffffffff00000000)
-	var x299 uint64
-	var x300 uint64
-	x300, x299 = bits.Mul64(x287, 0xffffffff)
-	var x301 uint64
-	var x302 uint64
-	x301, x302 = bits.Add64(x300, x297, uint64(0x0))
-	var x303 uint64
-	var x304 uint64
-	x303, x304 = bits.Add64(x298, x295, uint64(p384Uint1(x302)))
-	var x305 uint64
-	var x306 uint64
-	x305, x306 = bits.Add64(x296, x293, uint64(p384Uint1(x304)))
-	var x307 uint64
-	var x308 uint64
-	x307, x308 = bits.Add64(x294, x291, uint64(p384Uint1(x306)))
-	var x309 uint64
-	var x310 uint64
-	x309, x310 = bits.Add64(x292, x289, uint64(p384Uint1(x308)))
-	var x312 uint64
-	_, x312 = bits.Add64(x275, x299, uint64(0x0))
-	var x313 uint64
-	var x314 uint64
-	x313, x314 = bits.Add64(x277, x301, uint64(p384Uint1(x312)))
-	var x315 uint64
-	var x316 uint64
-	x315, x316 = bits.Add64(x279, x303, uint64(p384Uint1(x314)))
-	var x317 uint64
-	var x318 uint64
-	x317, x318 = bits.Add64(x281, x305, uint64(p384Uint1(x316)))
-	var x319 uint64
-	var x320 uint64
-	x319, x320 = bits.Add64(x283, x307, uint64(p384Uint1(x318)))
-	var x321 uint64
-	var x322 uint64
-	x321, x322 = bits.Add64(x285, x309, uint64(p384Uint1(x320)))
-	var x323 uint64
-	var x324 uint64
-	x323, x324 = bits.Add64((uint64(p384Uint1(x286)) + uint64(p384Uint1(x258))), (uint64(p384Uint1(x310)) + x290), uint64(p384Uint1(x322)))
-	var x325 uint64
-	var x326 uint64
-	x326, x325 = bits.Mul64(x5, 0x200000000)
-	var x327 uint64
-	var x328 uint64
-	x328, x327 = bits.Mul64(x5, 0xfffffffe00000000)
-	var x329 uint64
-	var x330 uint64
-	x330, x329 = bits.Mul64(x5, 0x200000000)
-	var x331 uint64
-	var x332 uint64
-	x332, x331 = bits.Mul64(x5, 0xfffffffe00000001)
-	var x333 uint64
-	var x334 uint64
-	x333, x334 = bits.Add64(x332, x329, uint64(0x0))
-	var x335 uint64
-	var x336 uint64
-	x335, x336 = bits.Add64(x330, x327, uint64(p384Uint1(x334)))
-	var x337 uint64
-	var x338 uint64
-	x337, x338 = bits.Add64(x328, x325, uint64(p384Uint1(x336)))
-	var x339 uint64
-	var x340 uint64
-	x339, x340 = bits.Add64(x326, x5, uint64(p384Uint1(x338)))
-	var x341 uint64
-	var x342 uint64
-	x341, x342 = bits.Add64(x313, x331, uint64(0x0))
-	var x343 uint64
-	var x344 uint64
-	x343, x344 = bits.Add64(x315, x333, uint64(p384Uint1(x342)))
-	var x345 uint64
-	var x346 uint64
-	x345, x346 = bits.Add64(x317, x335, uint64(p384Uint1(x344)))
-	var x347 uint64
-	var x348 uint64
-	x347, x348 = bits.Add64(x319, x337, uint64(p384Uint1(x346)))
-	var x349 uint64
-	var x350 uint64
-	x349, x350 = bits.Add64(x321, x339, uint64(p384Uint1(x348)))
-	var x351 uint64
-	var x352 uint64
-	x351, x352 = bits.Add64(x323, uint64(p384Uint1(x340)), uint64(p384Uint1(x350)))
-	var x353 uint64
-	_, x353 = bits.Mul64(x341, 0x100000001)
-	var x355 uint64
-	var x356 uint64
-	x356, x355 = bits.Mul64(x353, 0xffffffffffffffff)
-	var x357 uint64
-	var x358 uint64
-	x358, x357 = bits.Mul64(x353, 0xffffffffffffffff)
-	var x359 uint64
-	var x360 uint64
-	x360, x359 = bits.Mul64(x353, 0xffffffffffffffff)
-	var x361 uint64
-	var x362 uint64
-	x362, x361 = bits.Mul64(x353, 0xfffffffffffffffe)
-	var x363 uint64
-	var x364 uint64
-	x364, x363 = bits.Mul64(x353, 0xffffffff00000000)
-	var x365 uint64
-	var x366 uint64
-	x366, x365 = bits.Mul64(x353, 0xffffffff)
-	var x367 uint64
-	var x368 uint64
-	x367, x368 = bits.Add64(x366, x363, uint64(0x0))
-	var x369 uint64
-	var x370 uint64
-	x369, x370 = bits.Add64(x364, x361, uint64(p384Uint1(x368)))
-	var x371 uint64
-	var x372 uint64
-	x371, x372 = bits.Add64(x362, x359, uint64(p384Uint1(x370)))
-	var x373 uint64
-	var x374 uint64
-	x373, x374 = bits.Add64(x360, x357, uint64(p384Uint1(x372)))
-	var x375 uint64
-	var x376 uint64
-	x375, x376 = bits.Add64(x358, x355, uint64(p384Uint1(x374)))
-	var x378 uint64
-	_, x378 = bits.Add64(x341, x365, uint64(0x0))
-	var x379 uint64
-	var x380 uint64
-	x379, x380 = bits.Add64(x343, x367, uint64(p384Uint1(x378)))
-	var x381 uint64
-	var x382 uint64
-	x381, x382 = bits.Add64(x345, x369, uint64(p384Uint1(x380)))
-	var x383 uint64
-	var x384 uint64
-	x383, x384 = bits.Add64(x347, x371, uint64(p384Uint1(x382)))
-	var x385 uint64
-	var x386 uint64
-	x385, x386 = bits.Add64(x349, x373, uint64(p384Uint1(x384)))
-	var x387 uint64
-	var x388 uint64
-	x387, x388 = bits.Add64(x351, x375, uint64(p384Uint1(x386)))
-	var x389 uint64
-	var x390 uint64
-	x389, x390 = bits.Add64((uint64(p384Uint1(x352)) + uint64(p384Uint1(x324))), (uint64(p384Uint1(x376)) + x356), uint64(p384Uint1(x388)))
-	var x391 uint64
-	var x392 uint64
-	x391, x392 = bits.Sub64(x379, 0xffffffff, uint64(0x0))
-	var x393 uint64
-	var x394 uint64
-	x393, x394 = bits.Sub64(x381, 0xffffffff00000000, uint64(p384Uint1(x392)))
-	var x395 uint64
-	var x396 uint64
-	x395, x396 = bits.Sub64(x383, 0xfffffffffffffffe, uint64(p384Uint1(x394)))
-	var x397 uint64
-	var x398 uint64
-	x397, x398 = bits.Sub64(x385, 0xffffffffffffffff, uint64(p384Uint1(x396)))
-	var x399 uint64
-	var x400 uint64
-	x399, x400 = bits.Sub64(x387, 0xffffffffffffffff, uint64(p384Uint1(x398)))
-	var x401 uint64
-	var x402 uint64
-	x401, x402 = bits.Sub64(x389, 0xffffffffffffffff, uint64(p384Uint1(x400)))
-	var x404 uint64
-	_, x404 = bits.Sub64(uint64(p384Uint1(x390)), uint64(0x0), uint64(p384Uint1(x402)))
-	var x405 uint64
-	p384CmovznzU64(&x405, p384Uint1(x404), x391, x379)
-	var x406 uint64
-	p384CmovznzU64(&x406, p384Uint1(x404), x393, x381)
-	var x407 uint64
-	p384CmovznzU64(&x407, p384Uint1(x404), x395, x383)
-	var x408 uint64
-	p384CmovznzU64(&x408, p384Uint1(x404), x397, x385)
-	var x409 uint64
-	p384CmovznzU64(&x409, p384Uint1(x404), x399, x387)
-	var x410 uint64
-	p384CmovznzU64(&x410, p384Uint1(x404), x401, x389)
-	out1[0] = x405
-	out1[1] = x406
-	out1[2] = x407
-	out1[3] = x408
-	out1[4] = x409
-	out1[5] = x410
-}
-
-// p384Selectznz is a multi-limb conditional select.
-//
-// Postconditions:
-//   eval out1 = (if arg1 = 0 then eval arg2 else eval arg3)
-//
-// Input Bounds:
-//   arg1: [0x0 ~> 0x1]
-//   arg2: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
-//   arg3: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
-// Output Bounds:
-//   out1: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
-func p384Selectznz(out1 *[6]uint64, arg1 p384Uint1, arg2 *[6]uint64, arg3 *[6]uint64) {
-	var x1 uint64
-	p384CmovznzU64(&x1, arg1, arg2[0], arg3[0])
-	var x2 uint64
-	p384CmovznzU64(&x2, arg1, arg2[1], arg3[1])
-	var x3 uint64
-	p384CmovznzU64(&x3, arg1, arg2[2], arg3[2])
-	var x4 uint64
-	p384CmovznzU64(&x4, arg1, arg2[3], arg3[3])
-	var x5 uint64
-	p384CmovznzU64(&x5, arg1, arg2[4], arg3[4])
-	var x6 uint64
-	p384CmovznzU64(&x6, arg1, arg2[5], arg3[5])
-	out1[0] = x1
-	out1[1] = x2
-	out1[2] = x3
-	out1[3] = x4
-	out1[4] = x5
-	out1[5] = x6
-}
-
-// p384ToBytes serializes a field element NOT in the Montgomery domain to bytes in little-endian order.
-//
-// Preconditions:
-//   0 ≤ eval arg1 < m
-// Postconditions:
-//   out1 = map (λ x, ⌊((eval arg1 mod m) mod 2^(8 * (x + 1))) / 2^(8 * x)⌋) [0..47]
-//
-// Input Bounds:
-//   arg1: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
-// Output Bounds:
-//   out1: [[0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff]]
-func p384ToBytes(out1 *[48]uint8, arg1 *[6]uint64) {
-	x1 := arg1[5]
-	x2 := arg1[4]
-	x3 := arg1[3]
-	x4 := arg1[2]
-	x5 := arg1[1]
-	x6 := arg1[0]
-	x7 := (uint8(x6) & 0xff)
-	x8 := (x6 >> 8)
-	x9 := (uint8(x8) & 0xff)
-	x10 := (x8 >> 8)
-	x11 := (uint8(x10) & 0xff)
-	x12 := (x10 >> 8)
-	x13 := (uint8(x12) & 0xff)
-	x14 := (x12 >> 8)
-	x15 := (uint8(x14) & 0xff)
-	x16 := (x14 >> 8)
-	x17 := (uint8(x16) & 0xff)
-	x18 := (x16 >> 8)
-	x19 := (uint8(x18) & 0xff)
-	x20 := uint8((x18 >> 8))
-	x21 := (uint8(x5) & 0xff)
-	x22 := (x5 >> 8)
-	x23 := (uint8(x22) & 0xff)
-	x24 := (x22 >> 8)
-	x25 := (uint8(x24) & 0xff)
-	x26 := (x24 >> 8)
-	x27 := (uint8(x26) & 0xff)
-	x28 := (x26 >> 8)
-	x29 := (uint8(x28) & 0xff)
-	x30 := (x28 >> 8)
-	x31 := (uint8(x30) & 0xff)
-	x32 := (x30 >> 8)
-	x33 := (uint8(x32) & 0xff)
-	x34 := uint8((x32 >> 8))
-	x35 := (uint8(x4) & 0xff)
-	x36 := (x4 >> 8)
-	x37 := (uint8(x36) & 0xff)
-	x38 := (x36 >> 8)
-	x39 := (uint8(x38) & 0xff)
-	x40 := (x38 >> 8)
-	x41 := (uint8(x40) & 0xff)
-	x42 := (x40 >> 8)
-	x43 := (uint8(x42) & 0xff)
-	x44 := (x42 >> 8)
-	x45 := (uint8(x44) & 0xff)
-	x46 := (x44 >> 8)
-	x47 := (uint8(x46) & 0xff)
-	x48 := uint8((x46 >> 8))
-	x49 := (uint8(x3) & 0xff)
-	x50 := (x3 >> 8)
-	x51 := (uint8(x50) & 0xff)
-	x52 := (x50 >> 8)
-	x53 := (uint8(x52) & 0xff)
-	x54 := (x52 >> 8)
-	x55 := (uint8(x54) & 0xff)
-	x56 := (x54 >> 8)
-	x57 := (uint8(x56) & 0xff)
-	x58 := (x56 >> 8)
-	x59 := (uint8(x58) & 0xff)
-	x60 := (x58 >> 8)
-	x61 := (uint8(x60) & 0xff)
-	x62 := uint8((x60 >> 8))
-	x63 := (uint8(x2) & 0xff)
-	x64 := (x2 >> 8)
-	x65 := (uint8(x64) & 0xff)
-	x66 := (x64 >> 8)
-	x67 := (uint8(x66) & 0xff)
-	x68 := (x66 >> 8)
-	x69 := (uint8(x68) & 0xff)
-	x70 := (x68 >> 8)
-	x71 := (uint8(x70) & 0xff)
-	x72 := (x70 >> 8)
-	x73 := (uint8(x72) & 0xff)
-	x74 := (x72 >> 8)
-	x75 := (uint8(x74) & 0xff)
-	x76 := uint8((x74 >> 8))
-	x77 := (uint8(x1) & 0xff)
-	x78 := (x1 >> 8)
-	x79 := (uint8(x78) & 0xff)
-	x80 := (x78 >> 8)
-	x81 := (uint8(x80) & 0xff)
-	x82 := (x80 >> 8)
-	x83 := (uint8(x82) & 0xff)
-	x84 := (x82 >> 8)
-	x85 := (uint8(x84) & 0xff)
-	x86 := (x84 >> 8)
-	x87 := (uint8(x86) & 0xff)
-	x88 := (x86 >> 8)
-	x89 := (uint8(x88) & 0xff)
-	x90 := uint8((x88 >> 8))
-	out1[0] = x7
-	out1[1] = x9
-	out1[2] = x11
-	out1[3] = x13
-	out1[4] = x15
-	out1[5] = x17
-	out1[6] = x19
-	out1[7] = x20
-	out1[8] = x21
-	out1[9] = x23
-	out1[10] = x25
-	out1[11] = x27
-	out1[12] = x29
-	out1[13] = x31
-	out1[14] = x33
-	out1[15] = x34
-	out1[16] = x35
-	out1[17] = x37
-	out1[18] = x39
-	out1[19] = x41
-	out1[20] = x43
-	out1[21] = x45
-	out1[22] = x47
-	out1[23] = x48
-	out1[24] = x49
-	out1[25] = x51
-	out1[26] = x53
-	out1[27] = x55
-	out1[28] = x57
-	out1[29] = x59
-	out1[30] = x61
-	out1[31] = x62
-	out1[32] = x63
-	out1[33] = x65
-	out1[34] = x67
-	out1[35] = x69
-	out1[36] = x71
-	out1[37] = x73
-	out1[38] = x75
-	out1[39] = x76
-	out1[40] = x77
-	out1[41] = x79
-	out1[42] = x81
-	out1[43] = x83
-	out1[44] = x85
-	out1[45] = x87
-	out1[46] = x89
-	out1[47] = x90
-}
-
-// p384FromBytes deserializes a field element NOT in the Montgomery domain from bytes in little-endian order.
-//
-// Preconditions:
-//   0 ≤ bytes_eval arg1 < m
-// Postconditions:
-//   eval out1 mod m = bytes_eval arg1 mod m
-//   0 ≤ eval out1 < m
-//
-// Input Bounds:
-//   arg1: [[0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff]]
-// Output Bounds:
-//   out1: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
-func p384FromBytes(out1 *[6]uint64, arg1 *[48]uint8) {
-	x1 := (uint64(arg1[47]) << 56)
-	x2 := (uint64(arg1[46]) << 48)
-	x3 := (uint64(arg1[45]) << 40)
-	x4 := (uint64(arg1[44]) << 32)
-	x5 := (uint64(arg1[43]) << 24)
-	x6 := (uint64(arg1[42]) << 16)
-	x7 := (uint64(arg1[41]) << 8)
-	x8 := arg1[40]
-	x9 := (uint64(arg1[39]) << 56)
-	x10 := (uint64(arg1[38]) << 48)
-	x11 := (uint64(arg1[37]) << 40)
-	x12 := (uint64(arg1[36]) << 32)
-	x13 := (uint64(arg1[35]) << 24)
-	x14 := (uint64(arg1[34]) << 16)
-	x15 := (uint64(arg1[33]) << 8)
-	x16 := arg1[32]
-	x17 := (uint64(arg1[31]) << 56)
-	x18 := (uint64(arg1[30]) << 48)
-	x19 := (uint64(arg1[29]) << 40)
-	x20 := (uint64(arg1[28]) << 32)
-	x21 := (uint64(arg1[27]) << 24)
-	x22 := (uint64(arg1[26]) << 16)
-	x23 := (uint64(arg1[25]) << 8)
-	x24 := arg1[24]
-	x25 := (uint64(arg1[23]) << 56)
-	x26 := (uint64(arg1[22]) << 48)
-	x27 := (uint64(arg1[21]) << 40)
-	x28 := (uint64(arg1[20]) << 32)
-	x29 := (uint64(arg1[19]) << 24)
-	x30 := (uint64(arg1[18]) << 16)
-	x31 := (uint64(arg1[17]) << 8)
-	x32 := arg1[16]
-	x33 := (uint64(arg1[15]) << 56)
-	x34 := (uint64(arg1[14]) << 48)
-	x35 := (uint64(arg1[13]) << 40)
-	x36 := (uint64(arg1[12]) << 32)
-	x37 := (uint64(arg1[11]) << 24)
-	x38 := (uint64(arg1[10]) << 16)
-	x39 := (uint64(arg1[9]) << 8)
-	x40 := arg1[8]
-	x41 := (uint64(arg1[7]) << 56)
-	x42 := (uint64(arg1[6]) << 48)
-	x43 := (uint64(arg1[5]) << 40)
-	x44 := (uint64(arg1[4]) << 32)
-	x45 := (uint64(arg1[3]) << 24)
-	x46 := (uint64(arg1[2]) << 16)
-	x47 := (uint64(arg1[1]) << 8)
-	x48 := arg1[0]
-	x49 := (x47 + uint64(x48))
-	x50 := (x46 + x49)
-	x51 := (x45 + x50)
-	x52 := (x44 + x51)
-	x53 := (x43 + x52)
-	x54 := (x42 + x53)
-	x55 := (x41 + x54)
-	x56 := (x39 + uint64(x40))
-	x57 := (x38 + x56)
-	x58 := (x37 + x57)
-	x59 := (x36 + x58)
-	x60 := (x35 + x59)
-	x61 := (x34 + x60)
-	x62 := (x33 + x61)
-	x63 := (x31 + uint64(x32))
-	x64 := (x30 + x63)
-	x65 := (x29 + x64)
-	x66 := (x28 + x65)
-	x67 := (x27 + x66)
-	x68 := (x26 + x67)
-	x69 := (x25 + x68)
-	x70 := (x23 + uint64(x24))
-	x71 := (x22 + x70)
-	x72 := (x21 + x71)
-	x73 := (x20 + x72)
-	x74 := (x19 + x73)
-	x75 := (x18 + x74)
-	x76 := (x17 + x75)
-	x77 := (x15 + uint64(x16))
-	x78 := (x14 + x77)
-	x79 := (x13 + x78)
-	x80 := (x12 + x79)
-	x81 := (x11 + x80)
-	x82 := (x10 + x81)
-	x83 := (x9 + x82)
-	x84 := (x7 + uint64(x8))
-	x85 := (x6 + x84)
-	x86 := (x5 + x85)
-	x87 := (x4 + x86)
-	x88 := (x3 + x87)
-	x89 := (x2 + x88)
-	x90 := (x1 + x89)
-	out1[0] = x55
-	out1[1] = x62
-	out1[2] = x69
-	out1[3] = x76
-	out1[4] = x83
-	out1[5] = x90
-}
diff --git a/contrib/go/_std_1.18/src/crypto/elliptic/internal/fiat/p521_fiat64.go b/contrib/go/_std_1.18/src/crypto/elliptic/internal/fiat/p521_fiat64.go
deleted file mode 100644
index 9f4f290f4c..0000000000
--- a/contrib/go/_std_1.18/src/crypto/elliptic/internal/fiat/p521_fiat64.go
+++ /dev/null
@@ -1,5509 +0,0 @@
-// Code generated by Fiat Cryptography. DO NOT EDIT.
-//
-// Autogenerated: word_by_word_montgomery --lang Go --no-wide-int --cmovznz-by-mul --relax-primitive-carry-to-bitwidth 32,64 --internal-static --public-function-case camelCase --public-type-case camelCase --private-function-case camelCase --private-type-case camelCase --doc-text-before-function-name '' --doc-newline-before-package-declaration --doc-prepend-header 'Code generated by Fiat Cryptography. DO NOT EDIT.' --package-name fiat --no-prefix-fiat p521 64 '2^521 - 1' mul square add sub one from_montgomery to_montgomery selectznz to_bytes from_bytes
-//
-// curve description: p521
-//
-// machine_wordsize = 64 (from "64")
-//
-// requested operations: mul, square, add, sub, one, from_montgomery, to_montgomery, selectznz, to_bytes, from_bytes
-//
-// m = 0x1ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff (from "2^521 - 1")
-//
-//
-//
-// NOTE: In addition to the bounds specified above each function, all
-//
-//   functions synthesized for this Montgomery arithmetic require the
-//
-//   input to be strictly less than the prime modulus (m), and also
-//
-//   require the input to be in the unique saturated representation.
-//
-//   All functions also ensure that these two properties are true of
-//
-//   return values.
-//
-//
-//
-// Computed values:
-//
-//   eval z = z[0] + (z[1] << 64) + (z[2] << 128) + (z[3] << 192) + (z[4] << 256) + (z[5] << 0x140) + (z[6] << 0x180) + (z[7] << 0x1c0) + (z[8] << 2^9)
-//
-//   bytes_eval z = z[0] + (z[1] << 8) + (z[2] << 16) + (z[3] << 24) + (z[4] << 32) + (z[5] << 40) + (z[6] << 48) + (z[7] << 56) + (z[8] << 64) + (z[9] << 72) + (z[10] << 80) + (z[11] << 88) + (z[12] << 96) + (z[13] << 104) + (z[14] << 112) + (z[15] << 120) + (z[16] << 128) + (z[17] << 136) + (z[18] << 144) + (z[19] << 152) + (z[20] << 160) + (z[21] << 168) + (z[22] << 176) + (z[23] << 184) + (z[24] << 192) + (z[25] << 200) + (z[26] << 208) + (z[27] << 216) + (z[28] << 224) + (z[29] << 232) + (z[30] << 240) + (z[31] << 248) + (z[32] << 256) + (z[33] << 0x108) + (z[34] << 0x110) + (z[35] << 0x118) + (z[36] << 0x120) + (z[37] << 0x128) + (z[38] << 0x130) + (z[39] << 0x138) + (z[40] << 0x140) + (z[41] << 0x148) + (z[42] << 0x150) + (z[43] << 0x158) + (z[44] << 0x160) + (z[45] << 0x168) + (z[46] << 0x170) + (z[47] << 0x178) + (z[48] << 0x180) + (z[49] << 0x188) + (z[50] << 0x190) + (z[51] << 0x198) + (z[52] << 0x1a0) + (z[53] << 0x1a8) + (z[54] << 0x1b0) + (z[55] << 0x1b8) + (z[56] << 0x1c0) + (z[57] << 0x1c8) + (z[58] << 0x1d0) + (z[59] << 0x1d8) + (z[60] << 0x1e0) + (z[61] << 0x1e8) + (z[62] << 0x1f0) + (z[63] << 0x1f8) + (z[64] << 2^9) + (z[65] << 0x208)
-//
-//   twos_complement_eval z = let x1 := z[0] + (z[1] << 64) + (z[2] << 128) + (z[3] << 192) + (z[4] << 256) + (z[5] << 0x140) + (z[6] << 0x180) + (z[7] << 0x1c0) + (z[8] << 2^9) in
-//
-//                            if x1 & (2^576-1) < 2^575 then x1 & (2^576-1) else (x1 & (2^576-1)) - 2^576
-
-package fiat
-
-import "math/bits"
-
-type p521Uint1 uint64 // We use uint64 instead of a more narrow type for performance reasons; see https://github.com/mit-plv/fiat-crypto/pull/1006#issuecomment-892625927
-type p521Int1 int64   // We use uint64 instead of a more narrow type for performance reasons; see https://github.com/mit-plv/fiat-crypto/pull/1006#issuecomment-892625927
-
-// The type p521MontgomeryDomainFieldElement is a field element in the Montgomery domain.
-//
-// Bounds: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
-type p521MontgomeryDomainFieldElement [9]uint64
-
-// The type p521NonMontgomeryDomainFieldElement is a field element NOT in the Montgomery domain.
-//
-// Bounds: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
-type p521NonMontgomeryDomainFieldElement [9]uint64
-
-// p521CmovznzU64 is a single-word conditional move.
-//
-// Postconditions:
-//   out1 = (if arg1 = 0 then arg2 else arg3)
-//
-// Input Bounds:
-//   arg1: [0x0 ~> 0x1]
-//   arg2: [0x0 ~> 0xffffffffffffffff]
-//   arg3: [0x0 ~> 0xffffffffffffffff]
-// Output Bounds:
-//   out1: [0x0 ~> 0xffffffffffffffff]
-func p521CmovznzU64(out1 *uint64, arg1 p521Uint1, arg2 uint64, arg3 uint64) {
-	x1 := (uint64(arg1) * 0xffffffffffffffff)
-	x2 := ((x1 & arg3) | ((^x1) & arg2))
-	*out1 = x2
-}
-
-// p521Mul multiplies two field elements in the Montgomery domain.
-//
-// Preconditions:
-//   0 ≤ eval arg1 < m
-//   0 ≤ eval arg2 < m
-// Postconditions:
-//   eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) * eval (from_montgomery arg2)) mod m
-//   0 ≤ eval out1 < m
-//
-func p521Mul(out1 *p521MontgomeryDomainFieldElement, arg1 *p521MontgomeryDomainFieldElement, arg2 *p521MontgomeryDomainFieldElement) {
-	x1 := arg1[1]
-	x2 := arg1[2]
-	x3 := arg1[3]
-	x4 := arg1[4]
-	x5 := arg1[5]
-	x6 := arg1[6]
-	x7 := arg1[7]
-	x8 := arg1[8]
-	x9 := arg1[0]
-	var x10 uint64
-	var x11 uint64
-	x11, x10 = bits.Mul64(x9, arg2[8])
-	var x12 uint64
-	var x13 uint64
-	x13, x12 = bits.Mul64(x9, arg2[7])
-	var x14 uint64
-	var x15 uint64
-	x15, x14 = bits.Mul64(x9, arg2[6])
-	var x16 uint64
-	var x17 uint64
-	x17, x16 = bits.Mul64(x9, arg2[5])
-	var x18 uint64
-	var x19 uint64
-	x19, x18 = bits.Mul64(x9, arg2[4])
-	var x20 uint64
-	var x21 uint64
-	x21, x20 = bits.Mul64(x9, arg2[3])
-	var x22 uint64
-	var x23 uint64
-	x23, x22 = bits.Mul64(x9, arg2[2])
-	var x24 uint64
-	var x25 uint64
-	x25, x24 = bits.Mul64(x9, arg2[1])
-	var x26 uint64
-	var x27 uint64
-	x27, x26 = bits.Mul64(x9, arg2[0])
-	var x28 uint64
-	var x29 uint64
-	x28, x29 = bits.Add64(x27, x24, uint64(0x0))
-	var x30 uint64
-	var x31 uint64
-	x30, x31 = bits.Add64(x25, x22, uint64(p521Uint1(x29)))
-	var x32 uint64
-	var x33 uint64
-	x32, x33 = bits.Add64(x23, x20, uint64(p521Uint1(x31)))
-	var x34 uint64
-	var x35 uint64
-	x34, x35 = bits.Add64(x21, x18, uint64(p521Uint1(x33)))
-	var x36 uint64
-	var x37 uint64
-	x36, x37 = bits.Add64(x19, x16, uint64(p521Uint1(x35)))
-	var x38 uint64
-	var x39 uint64
-	x38, x39 = bits.Add64(x17, x14, uint64(p521Uint1(x37)))
-	var x40 uint64
-	var x41 uint64
-	x40, x41 = bits.Add64(x15, x12, uint64(p521Uint1(x39)))
-	var x42 uint64
-	var x43 uint64
-	x42, x43 = bits.Add64(x13, x10, uint64(p521Uint1(x41)))
-	x44 := (uint64(p521Uint1(x43)) + x11)
-	var x45 uint64
-	var x46 uint64
-	x46, x45 = bits.Mul64(x26, 0x1ff)
-	var x47 uint64
-	var x48 uint64
-	x48, x47 = bits.Mul64(x26, 0xffffffffffffffff)
-	var x49 uint64
-	var x50 uint64
-	x50, x49 = bits.Mul64(x26, 0xffffffffffffffff)
-	var x51 uint64
-	var x52 uint64
-	x52, x51 = bits.Mul64(x26, 0xffffffffffffffff)
-	var x53 uint64
-	var x54 uint64
-	x54, x53 = bits.Mul64(x26, 0xffffffffffffffff)
-	var x55 uint64
-	var x56 uint64
-	x56, x55 = bits.Mul64(x26, 0xffffffffffffffff)
-	var x57 uint64
-	var x58 uint64
-	x58, x57 = bits.Mul64(x26, 0xffffffffffffffff)
-	var x59 uint64
-	var x60 uint64
-	x60, x59 = bits.Mul64(x26, 0xffffffffffffffff)
-	var x61 uint64
-	var x62 uint64
-	x62, x61 = bits.Mul64(x26, 0xffffffffffffffff)
-	var x63 uint64
-	var x64 uint64
-	x63, x64 = bits.Add64(x62, x59, uint64(0x0))
-	var x65 uint64
-	var x66 uint64
-	x65, x66 = bits.Add64(x60, x57, uint64(p521Uint1(x64)))
-	var x67 uint64
-	var x68 uint64
-	x67, x68 = bits.Add64(x58, x55, uint64(p521Uint1(x66)))
-	var x69 uint64
-	var x70 uint64
-	x69, x70 = bits.Add64(x56, x53, uint64(p521Uint1(x68)))
-	var x71 uint64
-	var x72 uint64
-	x71, x72 = bits.Add64(x54, x51, uint64(p521Uint1(x70)))
-	var x73 uint64
-	var x74 uint64
-	x73, x74 = bits.Add64(x52, x49, uint64(p521Uint1(x72)))
-	var x75 uint64
-	var x76 uint64
-	x75, x76 = bits.Add64(x50, x47, uint64(p521Uint1(x74)))
-	var x77 uint64
-	var x78 uint64
-	x77, x78 = bits.Add64(x48, x45, uint64(p521Uint1(x76)))
-	x79 := (uint64(p521Uint1(x78)) + x46)
-	var x81 uint64
-	_, x81 = bits.Add64(x26, x61, uint64(0x0))
-	var x82 uint64
-	var x83 uint64
-	x82, x83 = bits.Add64(x28, x63, uint64(p521Uint1(x81)))
-	var x84 uint64
-	var x85 uint64
-	x84, x85 = bits.Add64(x30, x65, uint64(p521Uint1(x83)))
-	var x86 uint64
-	var x87 uint64
-	x86, x87 = bits.Add64(x32, x67, uint64(p521Uint1(x85)))
-	var x88 uint64
-	var x89 uint64
-	x88, x89 = bits.Add64(x34, x69, uint64(p521Uint1(x87)))
-	var x90 uint64
-	var x91 uint64
-	x90, x91 = bits.Add64(x36, x71, uint64(p521Uint1(x89)))
-	var x92 uint64
-	var x93 uint64
-	x92, x93 = bits.Add64(x38, x73, uint64(p521Uint1(x91)))
-	var x94 uint64
-	var x95 uint64
-	x94, x95 = bits.Add64(x40, x75, uint64(p521Uint1(x93)))
-	var x96 uint64
-	var x97 uint64
-	x96, x97 = bits.Add64(x42, x77, uint64(p521Uint1(x95)))
-	var x98 uint64
-	var x99 uint64
-	x98, x99 = bits.Add64(x44, x79, uint64(p521Uint1(x97)))
-	var x100 uint64
-	var x101 uint64
-	x101, x100 = bits.Mul64(x1, arg2[8])
-	var x102 uint64
-	var x103 uint64
-	x103, x102 = bits.Mul64(x1, arg2[7])
-	var x104 uint64
-	var x105 uint64
-	x105, x104 = bits.Mul64(x1, arg2[6])
-	var x106 uint64
-	var x107 uint64
-	x107, x106 = bits.Mul64(x1, arg2[5])
-	var x108 uint64
-	var x109 uint64
-	x109, x108 = bits.Mul64(x1, arg2[4])
-	var x110 uint64
-	var x111 uint64
-	x111, x110 = bits.Mul64(x1, arg2[3])
-	var x112 uint64
-	var x113 uint64
-	x113, x112 = bits.Mul64(x1, arg2[2])
-	var x114 uint64
-	var x115 uint64
-	x115, x114 = bits.Mul64(x1, arg2[1])
-	var x116 uint64
-	var x117 uint64
-	x117, x116 = bits.Mul64(x1, arg2[0])
-	var x118 uint64
-	var x119 uint64
-	x118, x119 = bits.Add64(x117, x114, uint64(0x0))
-	var x120 uint64
-	var x121 uint64
-	x120, x121 = bits.Add64(x115, x112, uint64(p521Uint1(x119)))
-	var x122 uint64
-	var x123 uint64
-	x122, x123 = bits.Add64(x113, x110, uint64(p521Uint1(x121)))
-	var x124 uint64
-	var x125 uint64
-	x124, x125 = bits.Add64(x111, x108, uint64(p521Uint1(x123)))
-	var x126 uint64
-	var x127 uint64
-	x126, x127 = bits.Add64(x109, x106, uint64(p521Uint1(x125)))
-	var x128 uint64
-	var x129 uint64
-	x128, x129 = bits.Add64(x107, x104, uint64(p521Uint1(x127)))
-	var x130 uint64
-	var x131 uint64
-	x130, x131 = bits.Add64(x105, x102, uint64(p521Uint1(x129)))
-	var x132 uint64
-	var x133 uint64
-	x132, x133 = bits.Add64(x103, x100, uint64(p521Uint1(x131)))
-	x134 := (uint64(p521Uint1(x133)) + x101)
-	var x135 uint64
-	var x136 uint64
-	x135, x136 = bits.Add64(x82, x116, uint64(0x0))
-	var x137 uint64
-	var x138 uint64
-	x137, x138 = bits.Add64(x84, x118, uint64(p521Uint1(x136)))
-	var x139 uint64
-	var x140 uint64
-	x139, x140 = bits.Add64(x86, x120, uint64(p521Uint1(x138)))
-	var x141 uint64
-	var x142 uint64
-	x141, x142 = bits.Add64(x88, x122, uint64(p521Uint1(x140)))
-	var x143 uint64
-	var x144 uint64
-	x143, x144 = bits.Add64(x90, x124, uint64(p521Uint1(x142)))
-	var x145 uint64
-	var x146 uint64
-	x145, x146 = bits.Add64(x92, x126, uint64(p521Uint1(x144)))
-	var x147 uint64
-	var x148 uint64
-	x147, x148 = bits.Add64(x94, x128, uint64(p521Uint1(x146)))
-	var x149 uint64
-	var x150 uint64
-	x149, x150 = bits.Add64(x96, x130, uint64(p521Uint1(x148)))
-	var x151 uint64
-	var x152 uint64
-	x151, x152 = bits.Add64(x98, x132, uint64(p521Uint1(x150)))
-	var x153 uint64
-	var x154 uint64
-	x153, x154 = bits.Add64(uint64(p521Uint1(x99)), x134, uint64(p521Uint1(x152)))
-	var x155 uint64
-	var x156 uint64
-	x156, x155 = bits.Mul64(x135, 0x1ff)
-	var x157 uint64
-	var x158 uint64
-	x158, x157 = bits.Mul64(x135, 0xffffffffffffffff)
-	var x159 uint64
-	var x160 uint64
-	x160, x159 = bits.Mul64(x135, 0xffffffffffffffff)
-	var x161 uint64
-	var x162 uint64
-	x162, x161 = bits.Mul64(x135, 0xffffffffffffffff)
-	var x163 uint64
-	var x164 uint64
-	x164, x163 = bits.Mul64(x135, 0xffffffffffffffff)
-	var x165 uint64
-	var x166 uint64
-	x166, x165 = bits.Mul64(x135, 0xffffffffffffffff)
-	var x167 uint64
-	var x168 uint64
-	x168, x167 = bits.Mul64(x135, 0xffffffffffffffff)
-	var x169 uint64
-	var x170 uint64
-	x170, x169 = bits.Mul64(x135, 0xffffffffffffffff)
-	var x171 uint64
-	var x172 uint64
-	x172, x171 = bits.Mul64(x135, 0xffffffffffffffff)
-	var x173 uint64
-	var x174 uint64
-	x173, x174 = bits.Add64(x172, x169, uint64(0x0))
-	var x175 uint64
-	var x176 uint64
-	x175, x176 = bits.Add64(x170, x167, uint64(p521Uint1(x174)))
-	var x177 uint64
-	var x178 uint64
-	x177, x178 = bits.Add64(x168, x165, uint64(p521Uint1(x176)))
-	var x179 uint64
-	var x180 uint64
-	x179, x180 = bits.Add64(x166, x163, uint64(p521Uint1(x178)))
-	var x181 uint64
-	var x182 uint64
-	x181, x182 = bits.Add64(x164, x161, uint64(p521Uint1(x180)))
-	var x183 uint64
-	var x184 uint64
-	x183, x184 = bits.Add64(x162, x159, uint64(p521Uint1(x182)))
-	var x185 uint64
-	var x186 uint64
-	x185, x186 = bits.Add64(x160, x157, uint64(p521Uint1(x184)))
-	var x187 uint64
-	var x188 uint64
-	x187, x188 = bits.Add64(x158, x155, uint64(p521Uint1(x186)))
-	x189 := (uint64(p521Uint1(x188)) + x156)
-	var x191 uint64
-	_, x191 = bits.Add64(x135, x171, uint64(0x0))
-	var x192 uint64
-	var x193 uint64
-	x192, x193 = bits.Add64(x137, x173, uint64(p521Uint1(x191)))
-	var x194 uint64
-	var x195 uint64
-	x194, x195 = bits.Add64(x139, x175, uint64(p521Uint1(x193)))
-	var x196 uint64
-	var x197 uint64
-	x196, x197 = bits.Add64(x141, x177, uint64(p521Uint1(x195)))
-	var x198 uint64
-	var x199 uint64
-	x198, x199 = bits.Add64(x143, x179, uint64(p521Uint1(x197)))
-	var x200 uint64
-	var x201 uint64
-	x200, x201 = bits.Add64(x145, x181, uint64(p521Uint1(x199)))
-	var x202 uint64
-	var x203 uint64
-	x202, x203 = bits.Add64(x147, x183, uint64(p521Uint1(x201)))
-	var x204 uint64
-	var x205 uint64
-	x204, x205 = bits.Add64(x149, x185, uint64(p521Uint1(x203)))
-	var x206 uint64
-	var x207 uint64
-	x206, x207 = bits.Add64(x151, x187, uint64(p521Uint1(x205)))
-	var x208 uint64
-	var x209 uint64
-	x208, x209 = bits.Add64(x153, x189, uint64(p521Uint1(x207)))
-	x210 := (uint64(p521Uint1(x209)) + uint64(p521Uint1(x154)))
-	var x211 uint64
-	var x212 uint64
-	x212, x211 = bits.Mul64(x2, arg2[8])
-	var x213 uint64
-	var x214 uint64
-	x214, x213 = bits.Mul64(x2, arg2[7])
-	var x215 uint64
-	var x216 uint64
-	x216, x215 = bits.Mul64(x2, arg2[6])
-	var x217 uint64
-	var x218 uint64
-	x218, x217 = bits.Mul64(x2, arg2[5])
-	var x219 uint64
-	var x220 uint64
-	x220, x219 = bits.Mul64(x2, arg2[4])
-	var x221 uint64
-	var x222 uint64
-	x222, x221 = bits.Mul64(x2, arg2[3])
-	var x223 uint64
-	var x224 uint64
-	x224, x223 = bits.Mul64(x2, arg2[2])
-	var x225 uint64
-	var x226 uint64
-	x226, x225 = bits.Mul64(x2, arg2[1])
-	var x227 uint64
-	var x228 uint64
-	x228, x227 = bits.Mul64(x2, arg2[0])
-	var x229 uint64
-	var x230 uint64
-	x229, x230 = bits.Add64(x228, x225, uint64(0x0))
-	var x231 uint64
-	var x232 uint64
-	x231, x232 = bits.Add64(x226, x223, uint64(p521Uint1(x230)))
-	var x233 uint64
-	var x234 uint64
-	x233, x234 = bits.Add64(x224, x221, uint64(p521Uint1(x232)))
-	var x235 uint64
-	var x236 uint64
-	x235, x236 = bits.Add64(x222, x219, uint64(p521Uint1(x234)))
-	var x237 uint64
-	var x238 uint64
-	x237, x238 = bits.Add64(x220, x217, uint64(p521Uint1(x236)))
-	var x239 uint64
-	var x240 uint64
-	x239, x240 = bits.Add64(x218, x215, uint64(p521Uint1(x238)))
-	var x241 uint64
-	var x242 uint64
-	x241, x242 = bits.Add64(x216, x213, uint64(p521Uint1(x240)))
-	var x243 uint64
-	var x244 uint64
-	x243, x244 = bits.Add64(x214, x211, uint64(p521Uint1(x242)))
-	x245 := (uint64(p521Uint1(x244)) + x212)
-	var x246 uint64
-	var x247 uint64
-	x246, x247 = bits.Add64(x192, x227, uint64(0x0))
-	var x248 uint64
-	var x249 uint64
-	x248, x249 = bits.Add64(x194, x229, uint64(p521Uint1(x247)))
-	var x250 uint64
-	var x251 uint64
-	x250, x251 = bits.Add64(x196, x231, uint64(p521Uint1(x249)))
-	var x252 uint64
-	var x253 uint64
-	x252, x253 = bits.Add64(x198, x233, uint64(p521Uint1(x251)))
-	var x254 uint64
-	var x255 uint64
-	x254, x255 = bits.Add64(x200, x235, uint64(p521Uint1(x253)))
-	var x256 uint64
-	var x257 uint64
-	x256, x257 = bits.Add64(x202, x237, uint64(p521Uint1(x255)))
-	var x258 uint64
-	var x259 uint64
-	x258, x259 = bits.Add64(x204, x239, uint64(p521Uint1(x257)))
-	var x260 uint64
-	var x261 uint64
-	x260, x261 = bits.Add64(x206, x241, uint64(p521Uint1(x259)))
-	var x262 uint64
-	var x263 uint64
-	x262, x263 = bits.Add64(x208, x243, uint64(p521Uint1(x261)))
-	var x264 uint64
-	var x265 uint64
-	x264, x265 = bits.Add64(x210, x245, uint64(p521Uint1(x263)))
-	var x266 uint64
-	var x267 uint64
-	x267, x266 = bits.Mul64(x246, 0x1ff)
-	var x268 uint64
-	var x269 uint64
-	x269, x268 = bits.Mul64(x246, 0xffffffffffffffff)
-	var x270 uint64
-	var x271 uint64
-	x271, x270 = bits.Mul64(x246, 0xffffffffffffffff)
-	var x272 uint64
-	var x273 uint64
-	x273, x272 = bits.Mul64(x246, 0xffffffffffffffff)
-	var x274 uint64
-	var x275 uint64
-	x275, x274 = bits.Mul64(x246, 0xffffffffffffffff)
-	var x276 uint64
-	var x277 uint64
-	x277, x276 = bits.Mul64(x246, 0xffffffffffffffff)
-	var x278 uint64
-	var x279 uint64
-	x279, x278 = bits.Mul64(x246, 0xffffffffffffffff)
-	var x280 uint64
-	var x281 uint64
-	x281, x280 = bits.Mul64(x246, 0xffffffffffffffff)
-	var x282 uint64
-	var x283 uint64
-	x283, x282 = bits.Mul64(x246, 0xffffffffffffffff)
-	var x284 uint64
-	var x285 uint64
-	x284, x285 = bits.Add64(x283, x280, uint64(0x0))
-	var x286 uint64
-	var x287 uint64
-	x286, x287 = bits.Add64(x281, x278, uint64(p521Uint1(x285)))
-	var x288 uint64
-	var x289 uint64
-	x288, x289 = bits.Add64(x279, x276, uint64(p521Uint1(x287)))
-	var x290 uint64
-	var x291 uint64
-	x290, x291 = bits.Add64(x277, x274, uint64(p521Uint1(x289)))
-	var x292 uint64
-	var x293 uint64
-	x292, x293 = bits.Add64(x275, x272, uint64(p521Uint1(x291)))
-	var x294 uint64
-	var x295 uint64
-	x294, x295 = bits.Add64(x273, x270, uint64(p521Uint1(x293)))
-	var x296 uint64
-	var x297 uint64
-	x296, x297 = bits.Add64(x271, x268, uint64(p521Uint1(x295)))
-	var x298 uint64
-	var x299 uint64
-	x298, x299 = bits.Add64(x269, x266, uint64(p521Uint1(x297)))
-	x300 := (uint64(p521Uint1(x299)) + x267)
-	var x302 uint64
-	_, x302 = bits.Add64(x246, x282, uint64(0x0))
-	var x303 uint64
-	var x304 uint64
-	x303, x304 = bits.Add64(x248, x284, uint64(p521Uint1(x302)))
-	var x305 uint64
-	var x306 uint64
-	x305, x306 = bits.Add64(x250, x286, uint64(p521Uint1(x304)))
-	var x307 uint64
-	var x308 uint64
-	x307, x308 = bits.Add64(x252, x288, uint64(p521Uint1(x306)))
-	var x309 uint64
-	var x310 uint64
-	x309, x310 = bits.Add64(x254, x290, uint64(p521Uint1(x308)))
-	var x311 uint64
-	var x312 uint64
-	x311, x312 = bits.Add64(x256, x292, uint64(p521Uint1(x310)))
-	var x313 uint64
-	var x314 uint64
-	x313, x314 = bits.Add64(x258, x294, uint64(p521Uint1(x312)))
-	var x315 uint64
-	var x316 uint64
-	x315, x316 = bits.Add64(x260, x296, uint64(p521Uint1(x314)))
-	var x317 uint64
-	var x318 uint64
-	x317, x318 = bits.Add64(x262, x298, uint64(p521Uint1(x316)))
-	var x319 uint64
-	var x320 uint64
-	x319, x320 = bits.Add64(x264, x300, uint64(p521Uint1(x318)))
-	x321 := (uint64(p521Uint1(x320)) + uint64(p521Uint1(x265)))
-	var x322 uint64
-	var x323 uint64
-	x323, x322 = bits.Mul64(x3, arg2[8])
-	var x324 uint64
-	var x325 uint64
-	x325, x324 = bits.Mul64(x3, arg2[7])
-	var x326 uint64
-	var x327 uint64
-	x327, x326 = bits.Mul64(x3, arg2[6])
-	var x328 uint64
-	var x329 uint64
-	x329, x328 = bits.Mul64(x3, arg2[5])
-	var x330 uint64
-	var x331 uint64
-	x331, x330 = bits.Mul64(x3, arg2[4])
-	var x332 uint64
-	var x333 uint64
-	x333, x332 = bits.Mul64(x3, arg2[3])
-	var x334 uint64
-	var x335 uint64
-	x335, x334 = bits.Mul64(x3, arg2[2])
-	var x336 uint64
-	var x337 uint64
-	x337, x336 = bits.Mul64(x3, arg2[1])
-	var x338 uint64
-	var x339 uint64
-	x339, x338 = bits.Mul64(x3, arg2[0])
-	var x340 uint64
-	var x341 uint64
-	x340, x341 = bits.Add64(x339, x336, uint64(0x0))
-	var x342 uint64
-	var x343 uint64
-	x342, x343 = bits.Add64(x337, x334, uint64(p521Uint1(x341)))
-	var x344 uint64
-	var x345 uint64
-	x344, x345 = bits.Add64(x335, x332, uint64(p521Uint1(x343)))
-	var x346 uint64
-	var x347 uint64
-	x346, x347 = bits.Add64(x333, x330, uint64(p521Uint1(x345)))
-	var x348 uint64
-	var x349 uint64
-	x348, x349 = bits.Add64(x331, x328, uint64(p521Uint1(x347)))
-	var x350 uint64
-	var x351 uint64
-	x350, x351 = bits.Add64(x329, x326, uint64(p521Uint1(x349)))
-	var x352 uint64
-	var x353 uint64
-	x352, x353 = bits.Add64(x327, x324, uint64(p521Uint1(x351)))
-	var x354 uint64
-	var x355 uint64
-	x354, x355 = bits.Add64(x325, x322, uint64(p521Uint1(x353)))
-	x356 := (uint64(p521Uint1(x355)) + x323)
-	var x357 uint64
-	var x358 uint64
-	x357, x358 = bits.Add64(x303, x338, uint64(0x0))
-	var x359 uint64
-	var x360 uint64
-	x359, x360 = bits.Add64(x305, x340, uint64(p521Uint1(x358)))
-	var x361 uint64
-	var x362 uint64
-	x361, x362 = bits.Add64(x307, x342, uint64(p521Uint1(x360)))
-	var x363 uint64
-	var x364 uint64
-	x363, x364 = bits.Add64(x309, x344, uint64(p521Uint1(x362)))
-	var x365 uint64
-	var x366 uint64
-	x365, x366 = bits.Add64(x311, x346, uint64(p521Uint1(x364)))
-	var x367 uint64
-	var x368 uint64
-	x367, x368 = bits.Add64(x313, x348, uint64(p521Uint1(x366)))
-	var x369 uint64
-	var x370 uint64
-	x369, x370 = bits.Add64(x315, x350, uint64(p521Uint1(x368)))
-	var x371 uint64
-	var x372 uint64
-	x371, x372 = bits.Add64(x317, x352, uint64(p521Uint1(x370)))
-	var x373 uint64
-	var x374 uint64
-	x373, x374 = bits.Add64(x319, x354, uint64(p521Uint1(x372)))
-	var x375 uint64
-	var x376 uint64
-	x375, x376 = bits.Add64(x321, x356, uint64(p521Uint1(x374)))
-	var x377 uint64
-	var x378 uint64
-	x378, x377 = bits.Mul64(x357, 0x1ff)
-	var x379 uint64
-	var x380 uint64
-	x380, x379 = bits.Mul64(x357, 0xffffffffffffffff)
-	var x381 uint64
-	var x382 uint64
-	x382, x381 = bits.Mul64(x357, 0xffffffffffffffff)
-	var x383 uint64
-	var x384 uint64
-	x384, x383 = bits.Mul64(x357, 0xffffffffffffffff)
-	var x385 uint64
-	var x386 uint64
-	x386, x385 = bits.Mul64(x357, 0xffffffffffffffff)
-	var x387 uint64
-	var x388 uint64
-	x388, x387 = bits.Mul64(x357, 0xffffffffffffffff)
-	var x389 uint64
-	var x390 uint64
-	x390, x389 = bits.Mul64(x357, 0xffffffffffffffff)
-	var x391 uint64
-	var x392 uint64
-	x392, x391 = bits.Mul64(x357, 0xffffffffffffffff)
-	var x393 uint64
-	var x394 uint64
-	x394, x393 = bits.Mul64(x357, 0xffffffffffffffff)
-	var x395 uint64
-	var x396 uint64
-	x395, x396 = bits.Add64(x394, x391, uint64(0x0))
-	var x397 uint64
-	var x398 uint64
-	x397, x398 = bits.Add64(x392, x389, uint64(p521Uint1(x396)))
-	var x399 uint64
-	var x400 uint64
-	x399, x400 = bits.Add64(x390, x387, uint64(p521Uint1(x398)))
-	var x401 uint64
-	var x402 uint64
-	x401, x402 = bits.Add64(x388, x385, uint64(p521Uint1(x400)))
-	var x403 uint64
-	var x404 uint64
-	x403, x404 = bits.Add64(x386, x383, uint64(p521Uint1(x402)))
-	var x405 uint64
-	var x406 uint64
-	x405, x406 = bits.Add64(x384, x381, uint64(p521Uint1(x404)))
-	var x407 uint64
-	var x408 uint64
-	x407, x408 = bits.Add64(x382, x379, uint64(p521Uint1(x406)))
-	var x409 uint64
-	var x410 uint64
-	x409, x410 = bits.Add64(x380, x377, uint64(p521Uint1(x408)))
-	x411 := (uint64(p521Uint1(x410)) + x378)
-	var x413 uint64
-	_, x413 = bits.Add64(x357, x393, uint64(0x0))
-	var x414 uint64
-	var x415 uint64
-	x414, x415 = bits.Add64(x359, x395, uint64(p521Uint1(x413)))
-	var x416 uint64
-	var x417 uint64
-	x416, x417 = bits.Add64(x361, x397, uint64(p521Uint1(x415)))
-	var x418 uint64
-	var x419 uint64
-	x418, x419 = bits.Add64(x363, x399, uint64(p521Uint1(x417)))
-	var x420 uint64
-	var x421 uint64
-	x420, x421 = bits.Add64(x365, x401, uint64(p521Uint1(x419)))
-	var x422 uint64
-	var x423 uint64
-	x422, x423 = bits.Add64(x367, x403, uint64(p521Uint1(x421)))
-	var x424 uint64
-	var x425 uint64
-	x424, x425 = bits.Add64(x369, x405, uint64(p521Uint1(x423)))
-	var x426 uint64
-	var x427 uint64
-	x426, x427 = bits.Add64(x371, x407, uint64(p521Uint1(x425)))
-	var x428 uint64
-	var x429 uint64
-	x428, x429 = bits.Add64(x373, x409, uint64(p521Uint1(x427)))
-	var x430 uint64
-	var x431 uint64
-	x430, x431 = bits.Add64(x375, x411, uint64(p521Uint1(x429)))
-	x432 := (uint64(p521Uint1(x431)) + uint64(p521Uint1(x376)))
-	var x433 uint64
-	var x434 uint64
-	x434, x433 = bits.Mul64(x4, arg2[8])
-	var x435 uint64
-	var x436 uint64
-	x436, x435 = bits.Mul64(x4, arg2[7])
-	var x437 uint64
-	var x438 uint64
-	x438, x437 = bits.Mul64(x4, arg2[6])
-	var x439 uint64
-	var x440 uint64
-	x440, x439 = bits.Mul64(x4, arg2[5])
-	var x441 uint64
-	var x442 uint64
-	x442, x441 = bits.Mul64(x4, arg2[4])
-	var x443 uint64
-	var x444 uint64
-	x444, x443 = bits.Mul64(x4, arg2[3])
-	var x445 uint64
-	var x446 uint64
-	x446, x445 = bits.Mul64(x4, arg2[2])
-	var x447 uint64
-	var x448 uint64
-	x448, x447 = bits.Mul64(x4, arg2[1])
-	var x449 uint64
-	var x450 uint64
-	x450, x449 = bits.Mul64(x4, arg2[0])
-	var x451 uint64
-	var x452 uint64
-	x451, x452 = bits.Add64(x450, x447, uint64(0x0))
-	var x453 uint64
-	var x454 uint64
-	x453, x454 = bits.Add64(x448, x445, uint64(p521Uint1(x452)))
-	var x455 uint64
-	var x456 uint64
-	x455, x456 = bits.Add64(x446, x443, uint64(p521Uint1(x454)))
-	var x457 uint64
-	var x458 uint64
-	x457, x458 = bits.Add64(x444, x441, uint64(p521Uint1(x456)))
-	var x459 uint64
-	var x460 uint64
-	x459, x460 = bits.Add64(x442, x439, uint64(p521Uint1(x458)))
-	var x461 uint64
-	var x462 uint64
-	x461, x462 = bits.Add64(x440, x437, uint64(p521Uint1(x460)))
-	var x463 uint64
-	var x464 uint64
-	x463, x464 = bits.Add64(x438, x435, uint64(p521Uint1(x462)))
-	var x465 uint64
-	var x466 uint64
-	x465, x466 = bits.Add64(x436, x433, uint64(p521Uint1(x464)))
-	x467 := (uint64(p521Uint1(x466)) + x434)
-	var x468 uint64
-	var x469 uint64
-	x468, x469 = bits.Add64(x414, x449, uint64(0x0))
-	var x470 uint64
-	var x471 uint64
-	x470, x471 = bits.Add64(x416, x451, uint64(p521Uint1(x469)))
-	var x472 uint64
-	var x473 uint64
-	x472, x473 = bits.Add64(x418, x453, uint64(p521Uint1(x471)))
-	var x474 uint64
-	var x475 uint64
-	x474, x475 = bits.Add64(x420, x455, uint64(p521Uint1(x473)))
-	var x476 uint64
-	var x477 uint64
-	x476, x477 = bits.Add64(x422, x457, uint64(p521Uint1(x475)))
-	var x478 uint64
-	var x479 uint64
-	x478, x479 = bits.Add64(x424, x459, uint64(p521Uint1(x477)))
-	var x480 uint64
-	var x481 uint64
-	x480, x481 = bits.Add64(x426, x461, uint64(p521Uint1(x479)))
-	var x482 uint64
-	var x483 uint64
-	x482, x483 = bits.Add64(x428, x463, uint64(p521Uint1(x481)))
-	var x484 uint64
-	var x485 uint64
-	x484, x485 = bits.Add64(x430, x465, uint64(p521Uint1(x483)))
-	var x486 uint64
-	var x487 uint64
-	x486, x487 = bits.Add64(x432, x467, uint64(p521Uint1(x485)))
-	var x488 uint64
-	var x489 uint64
-	x489, x488 = bits.Mul64(x468, 0x1ff)
-	var x490 uint64
-	var x491 uint64
-	x491, x490 = bits.Mul64(x468, 0xffffffffffffffff)
-	var x492 uint64
-	var x493 uint64
-	x493, x492 = bits.Mul64(x468, 0xffffffffffffffff)
-	var x494 uint64
-	var x495 uint64
-	x495, x494 = bits.Mul64(x468, 0xffffffffffffffff)
-	var x496 uint64
-	var x497 uint64
-	x497, x496 = bits.Mul64(x468, 0xffffffffffffffff)
-	var x498 uint64
-	var x499 uint64
-	x499, x498 = bits.Mul64(x468, 0xffffffffffffffff)
-	var x500 uint64
-	var x501 uint64
-	x501, x500 = bits.Mul64(x468, 0xffffffffffffffff)
-	var x502 uint64
-	var x503 uint64
-	x503, x502 = bits.Mul64(x468, 0xffffffffffffffff)
-	var x504 uint64
-	var x505 uint64
-	x505, x504 = bits.Mul64(x468, 0xffffffffffffffff)
-	var x506 uint64
-	var x507 uint64
-	x506, x507 = bits.Add64(x505, x502, uint64(0x0))
-	var x508 uint64
-	var x509 uint64
-	x508, x509 = bits.Add64(x503, x500, uint64(p521Uint1(x507)))
-	var x510 uint64
-	var x511 uint64
-	x510, x511 = bits.Add64(x501, x498, uint64(p521Uint1(x509)))
-	var x512 uint64
-	var x513 uint64
-	x512, x513 = bits.Add64(x499, x496, uint64(p521Uint1(x511)))
-	var x514 uint64
-	var x515 uint64
-	x514, x515 = bits.Add64(x497, x494, uint64(p521Uint1(x513)))
-	var x516 uint64
-	var x517 uint64
-	x516, x517 = bits.Add64(x495, x492, uint64(p521Uint1(x515)))
-	var x518 uint64
-	var x519 uint64
-	x518, x519 = bits.Add64(x493, x490, uint64(p521Uint1(x517)))
-	var x520 uint64
-	var x521 uint64
-	x520, x521 = bits.Add64(x491, x488, uint64(p521Uint1(x519)))
-	x522 := (uint64(p521Uint1(x521)) + x489)
-	var x524 uint64
-	_, x524 = bits.Add64(x468, x504, uint64(0x0))
-	var x525 uint64
-	var x526 uint64
-	x525, x526 = bits.Add64(x470, x506, uint64(p521Uint1(x524)))
-	var x527 uint64
-	var x528 uint64
-	x527, x528 = bits.Add64(x472, x508, uint64(p521Uint1(x526)))
-	var x529 uint64
-	var x530 uint64
-	x529, x530 = bits.Add64(x474, x510, uint64(p521Uint1(x528)))
-	var x531 uint64
-	var x532 uint64
-	x531, x532 = bits.Add64(x476, x512, uint64(p521Uint1(x530)))
-	var x533 uint64
-	var x534 uint64
-	x533, x534 = bits.Add64(x478, x514, uint64(p521Uint1(x532)))
-	var x535 uint64
-	var x536 uint64
-	x535, x536 = bits.Add64(x480, x516, uint64(p521Uint1(x534)))
-	var x537 uint64
-	var x538 uint64
-	x537, x538 = bits.Add64(x482, x518, uint64(p521Uint1(x536)))
-	var x539 uint64
-	var x540 uint64
-	x539, x540 = bits.Add64(x484, x520, uint64(p521Uint1(x538)))
-	var x541 uint64
-	var x542 uint64
-	x541, x542 = bits.Add64(x486, x522, uint64(p521Uint1(x540)))
-	x543 := (uint64(p521Uint1(x542)) + uint64(p521Uint1(x487)))
-	var x544 uint64
-	var x545 uint64
-	x545, x544 = bits.Mul64(x5, arg2[8])
-	var x546 uint64
-	var x547 uint64
-	x547, x546 = bits.Mul64(x5, arg2[7])
-	var x548 uint64
-	var x549 uint64
-	x549, x548 = bits.Mul64(x5, arg2[6])
-	var x550 uint64
-	var x551 uint64
-	x551, x550 = bits.Mul64(x5, arg2[5])
-	var x552 uint64
-	var x553 uint64
-	x553, x552 = bits.Mul64(x5, arg2[4])
-	var x554 uint64
-	var x555 uint64
-	x555, x554 = bits.Mul64(x5, arg2[3])
-	var x556 uint64
-	var x557 uint64
-	x557, x556 = bits.Mul64(x5, arg2[2])
-	var x558 uint64
-	var x559 uint64
-	x559, x558 = bits.Mul64(x5, arg2[1])
-	var x560 uint64
-	var x561 uint64
-	x561, x560 = bits.Mul64(x5, arg2[0])
-	var x562 uint64
-	var x563 uint64
-	x562, x563 = bits.Add64(x561, x558, uint64(0x0))
-	var x564 uint64
-	var x565 uint64
-	x564, x565 = bits.Add64(x559, x556, uint64(p521Uint1(x563)))
-	var x566 uint64
-	var x567 uint64
-	x566, x567 = bits.Add64(x557, x554, uint64(p521Uint1(x565)))
-	var x568 uint64
-	var x569 uint64
-	x568, x569 = bits.Add64(x555, x552, uint64(p521Uint1(x567)))
-	var x570 uint64
-	var x571 uint64
-	x570, x571 = bits.Add64(x553, x550, uint64(p521Uint1(x569)))
-	var x572 uint64
-	var x573 uint64
-	x572, x573 = bits.Add64(x551, x548, uint64(p521Uint1(x571)))
-	var x574 uint64
-	var x575 uint64
-	x574, x575 = bits.Add64(x549, x546, uint64(p521Uint1(x573)))
-	var x576 uint64
-	var x577 uint64
-	x576, x577 = bits.Add64(x547, x544, uint64(p521Uint1(x575)))
-	x578 := (uint64(p521Uint1(x577)) + x545)
-	var x579 uint64
-	var x580 uint64
-	x579, x580 = bits.Add64(x525, x560, uint64(0x0))
-	var x581 uint64
-	var x582 uint64
-	x581, x582 = bits.Add64(x527, x562, uint64(p521Uint1(x580)))
-	var x583 uint64
-	var x584 uint64
-	x583, x584 = bits.Add64(x529, x564, uint64(p521Uint1(x582)))
-	var x585 uint64
-	var x586 uint64
-	x585, x586 = bits.Add64(x531, x566, uint64(p521Uint1(x584)))
-	var x587 uint64
-	var x588 uint64
-	x587, x588 = bits.Add64(x533, x568, uint64(p521Uint1(x586)))
-	var x589 uint64
-	var x590 uint64
-	x589, x590 = bits.Add64(x535, x570, uint64(p521Uint1(x588)))
-	var x591 uint64
-	var x592 uint64
-	x591, x592 = bits.Add64(x537, x572, uint64(p521Uint1(x590)))
-	var x593 uint64
-	var x594 uint64
-	x593, x594 = bits.Add64(x539, x574, uint64(p521Uint1(x592)))
-	var x595 uint64
-	var x596 uint64
-	x595, x596 = bits.Add64(x541, x576, uint64(p521Uint1(x594)))
-	var x597 uint64
-	var x598 uint64
-	x597, x598 = bits.Add64(x543, x578, uint64(p521Uint1(x596)))
-	var x599 uint64
-	var x600 uint64
-	x600, x599 = bits.Mul64(x579, 0x1ff)
-	var x601 uint64
-	var x602 uint64
-	x602, x601 = bits.Mul64(x579, 0xffffffffffffffff)
-	var x603 uint64
-	var x604 uint64
-	x604, x603 = bits.Mul64(x579, 0xffffffffffffffff)
-	var x605 uint64
-	var x606 uint64
-	x606, x605 = bits.Mul64(x579, 0xffffffffffffffff)
-	var x607 uint64
-	var x608 uint64
-	x608, x607 = bits.Mul64(x579, 0xffffffffffffffff)
-	var x609 uint64
-	var x610 uint64
-	x610, x609 = bits.Mul64(x579, 0xffffffffffffffff)
-	var x611 uint64
-	var x612 uint64
-	x612, x611 = bits.Mul64(x579, 0xffffffffffffffff)
-	var x613 uint64
-	var x614 uint64
-	x614, x613 = bits.Mul64(x579, 0xffffffffffffffff)
-	var x615 uint64
-	var x616 uint64
-	x616, x615 = bits.Mul64(x579, 0xffffffffffffffff)
-	var x617 uint64
-	var x618 uint64
-	x617, x618 = bits.Add64(x616, x613, uint64(0x0))
-	var x619 uint64
-	var x620 uint64
-	x619, x620 = bits.Add64(x614, x611, uint64(p521Uint1(x618)))
-	var x621 uint64
-	var x622 uint64
-	x621, x622 = bits.Add64(x612, x609, uint64(p521Uint1(x620)))
-	var x623 uint64
-	var x624 uint64
-	x623, x624 = bits.Add64(x610, x607, uint64(p521Uint1(x622)))
-	var x625 uint64
-	var x626 uint64
-	x625, x626 = bits.Add64(x608, x605, uint64(p521Uint1(x624)))
-	var x627 uint64
-	var x628 uint64
-	x627, x628 = bits.Add64(x606, x603, uint64(p521Uint1(x626)))
-	var x629 uint64
-	var x630 uint64
-	x629, x630 = bits.Add64(x604, x601, uint64(p521Uint1(x628)))
-	var x631 uint64
-	var x632 uint64
-	x631, x632 = bits.Add64(x602, x599, uint64(p521Uint1(x630)))
-	x633 := (uint64(p521Uint1(x632)) + x600)
-	var x635 uint64
-	_, x635 = bits.Add64(x579, x615, uint64(0x0))
-	var x636 uint64
-	var x637 uint64
-	x636, x637 = bits.Add64(x581, x617, uint64(p521Uint1(x635)))
-	var x638 uint64
-	var x639 uint64
-	x638, x639 = bits.Add64(x583, x619, uint64(p521Uint1(x637)))
-	var x640 uint64
-	var x641 uint64
-	x640, x641 = bits.Add64(x585, x621, uint64(p521Uint1(x639)))
-	var x642 uint64
-	var x643 uint64
-	x642, x643 = bits.Add64(x587, x623, uint64(p521Uint1(x641)))
-	var x644 uint64
-	var x645 uint64
-	x644, x645 = bits.Add64(x589, x625, uint64(p521Uint1(x643)))
-	var x646 uint64
-	var x647 uint64
-	x646, x647 = bits.Add64(x591, x627, uint64(p521Uint1(x645)))
-	var x648 uint64
-	var x649 uint64
-	x648, x649 = bits.Add64(x593, x629, uint64(p521Uint1(x647)))
-	var x650 uint64
-	var x651 uint64
-	x650, x651 = bits.Add64(x595, x631, uint64(p521Uint1(x649)))
-	var x652 uint64
-	var x653 uint64
-	x652, x653 = bits.Add64(x597, x633, uint64(p521Uint1(x651)))
-	x654 := (uint64(p521Uint1(x653)) + uint64(p521Uint1(x598)))
-	var x655 uint64
-	var x656 uint64
-	x656, x655 = bits.Mul64(x6, arg2[8])
-	var x657 uint64
-	var x658 uint64
-	x658, x657 = bits.Mul64(x6, arg2[7])
-	var x659 uint64
-	var x660 uint64
-	x660, x659 = bits.Mul64(x6, arg2[6])
-	var x661 uint64
-	var x662 uint64
-	x662, x661 = bits.Mul64(x6, arg2[5])
-	var x663 uint64
-	var x664 uint64
-	x664, x663 = bits.Mul64(x6, arg2[4])
-	var x665 uint64
-	var x666 uint64
-	x666, x665 = bits.Mul64(x6, arg2[3])
-	var x667 uint64
-	var x668 uint64
-	x668, x667 = bits.Mul64(x6, arg2[2])
-	var x669 uint64
-	var x670 uint64
-	x670, x669 = bits.Mul64(x6, arg2[1])
-	var x671 uint64
-	var x672 uint64
-	x672, x671 = bits.Mul64(x6, arg2[0])
-	var x673 uint64
-	var x674 uint64
-	x673, x674 = bits.Add64(x672, x669, uint64(0x0))
-	var x675 uint64
-	var x676 uint64
-	x675, x676 = bits.Add64(x670, x667, uint64(p521Uint1(x674)))
-	var x677 uint64
-	var x678 uint64
-	x677, x678 = bits.Add64(x668, x665, uint64(p521Uint1(x676)))
-	var x679 uint64
-	var x680 uint64
-	x679, x680 = bits.Add64(x666, x663, uint64(p521Uint1(x678)))
-	var x681 uint64
-	var x682 uint64
-	x681, x682 = bits.Add64(x664, x661, uint64(p521Uint1(x680)))
-	var x683 uint64
-	var x684 uint64
-	x683, x684 = bits.Add64(x662, x659, uint64(p521Uint1(x682)))
-	var x685 uint64
-	var x686 uint64
-	x685, x686 = bits.Add64(x660, x657, uint64(p521Uint1(x684)))
-	var x687 uint64
-	var x688 uint64
-	x687, x688 = bits.Add64(x658, x655, uint64(p521Uint1(x686)))
-	x689 := (uint64(p521Uint1(x688)) + x656)
-	var x690 uint64
-	var x691 uint64
-	x690, x691 = bits.Add64(x636, x671, uint64(0x0))
-	var x692 uint64
-	var x693 uint64
-	x692, x693 = bits.Add64(x638, x673, uint64(p521Uint1(x691)))
-	var x694 uint64
-	var x695 uint64
-	x694, x695 = bits.Add64(x640, x675, uint64(p521Uint1(x693)))
-	var x696 uint64
-	var x697 uint64
-	x696, x697 = bits.Add64(x642, x677, uint64(p521Uint1(x695)))
-	var x698 uint64
-	var x699 uint64
-	x698, x699 = bits.Add64(x644, x679, uint64(p521Uint1(x697)))
-	var x700 uint64
-	var x701 uint64
-	x700, x701 = bits.Add64(x646, x681, uint64(p521Uint1(x699)))
-	var x702 uint64
-	var x703 uint64
-	x702, x703 = bits.Add64(x648, x683, uint64(p521Uint1(x701)))
-	var x704 uint64
-	var x705 uint64
-	x704, x705 = bits.Add64(x650, x685, uint64(p521Uint1(x703)))
-	var x706 uint64
-	var x707 uint64
-	x706, x707 = bits.Add64(x652, x687, uint64(p521Uint1(x705)))
-	var x708 uint64
-	var x709 uint64
-	x708, x709 = bits.Add64(x654, x689, uint64(p521Uint1(x707)))
-	var x710 uint64
-	var x711 uint64
-	x711, x710 = bits.Mul64(x690, 0x1ff)
-	var x712 uint64
-	var x713 uint64
-	x713, x712 = bits.Mul64(x690, 0xffffffffffffffff)
-	var x714 uint64
-	var x715 uint64
-	x715, x714 = bits.Mul64(x690, 0xffffffffffffffff)
-	var x716 uint64
-	var x717 uint64
-	x717, x716 = bits.Mul64(x690, 0xffffffffffffffff)
-	var x718 uint64
-	var x719 uint64
-	x719, x718 = bits.Mul64(x690, 0xffffffffffffffff)
-	var x720 uint64
-	var x721 uint64
-	x721, x720 = bits.Mul64(x690, 0xffffffffffffffff)
-	var x722 uint64
-	var x723 uint64
-	x723, x722 = bits.Mul64(x690, 0xffffffffffffffff)
-	var x724 uint64
-	var x725 uint64
-	x725, x724 = bits.Mul64(x690, 0xffffffffffffffff)
-	var x726 uint64
-	var x727 uint64
-	x727, x726 = bits.Mul64(x690, 0xffffffffffffffff)
-	var x728 uint64
-	var x729 uint64
-	x728, x729 = bits.Add64(x727, x724, uint64(0x0))
-	var x730 uint64
-	var x731 uint64
-	x730, x731 = bits.Add64(x725, x722, uint64(p521Uint1(x729)))
-	var x732 uint64
-	var x733 uint64
-	x732, x733 = bits.Add64(x723, x720, uint64(p521Uint1(x731)))
-	var x734 uint64
-	var x735 uint64
-	x734, x735 = bits.Add64(x721, x718, uint64(p521Uint1(x733)))
-	var x736 uint64
-	var x737 uint64
-	x736, x737 = bits.Add64(x719, x716, uint64(p521Uint1(x735)))
-	var x738 uint64
-	var x739 uint64
-	x738, x739 = bits.Add64(x717, x714, uint64(p521Uint1(x737)))
-	var x740 uint64
-	var x741 uint64
-	x740, x741 = bits.Add64(x715, x712, uint64(p521Uint1(x739)))
-	var x742 uint64
-	var x743 uint64
-	x742, x743 = bits.Add64(x713, x710, uint64(p521Uint1(x741)))
-	x744 := (uint64(p521Uint1(x743)) + x711)
-	var x746 uint64
-	_, x746 = bits.Add64(x690, x726, uint64(0x0))
-	var x747 uint64
-	var x748 uint64
-	x747, x748 = bits.Add64(x692, x728, uint64(p521Uint1(x746)))
-	var x749 uint64
-	var x750 uint64
-	x749, x750 = bits.Add64(x694, x730, uint64(p521Uint1(x748)))
-	var x751 uint64
-	var x752 uint64
-	x751, x752 = bits.Add64(x696, x732, uint64(p521Uint1(x750)))
-	var x753 uint64
-	var x754 uint64
-	x753, x754 = bits.Add64(x698, x734, uint64(p521Uint1(x752)))
-	var x755 uint64
-	var x756 uint64
-	x755, x756 = bits.Add64(x700, x736, uint64(p521Uint1(x754)))
-	var x757 uint64
-	var x758 uint64
-	x757, x758 = bits.Add64(x702, x738, uint64(p521Uint1(x756)))
-	var x759 uint64
-	var x760 uint64
-	x759, x760 = bits.Add64(x704, x740, uint64(p521Uint1(x758)))
-	var x761 uint64
-	var x762 uint64
-	x761, x762 = bits.Add64(x706, x742, uint64(p521Uint1(x760)))
-	var x763 uint64
-	var x764 uint64
-	x763, x764 = bits.Add64(x708, x744, uint64(p521Uint1(x762)))
-	x765 := (uint64(p521Uint1(x764)) + uint64(p521Uint1(x709)))
-	var x766 uint64
-	var x767 uint64
-	x767, x766 = bits.Mul64(x7, arg2[8])
-	var x768 uint64
-	var x769 uint64
-	x769, x768 = bits.Mul64(x7, arg2[7])
-	var x770 uint64
-	var x771 uint64
-	x771, x770 = bits.Mul64(x7, arg2[6])
-	var x772 uint64
-	var x773 uint64
-	x773, x772 = bits.Mul64(x7, arg2[5])
-	var x774 uint64
-	var x775 uint64
-	x775, x774 = bits.Mul64(x7, arg2[4])
-	var x776 uint64
-	var x777 uint64
-	x777, x776 = bits.Mul64(x7, arg2[3])
-	var x778 uint64
-	var x779 uint64
-	x779, x778 = bits.Mul64(x7, arg2[2])
-	var x780 uint64
-	var x781 uint64
-	x781, x780 = bits.Mul64(x7, arg2[1])
-	var x782 uint64
-	var x783 uint64
-	x783, x782 = bits.Mul64(x7, arg2[0])
-	var x784 uint64
-	var x785 uint64
-	x784, x785 = bits.Add64(x783, x780, uint64(0x0))
-	var x786 uint64
-	var x787 uint64
-	x786, x787 = bits.Add64(x781, x778, uint64(p521Uint1(x785)))
-	var x788 uint64
-	var x789 uint64
-	x788, x789 = bits.Add64(x779, x776, uint64(p521Uint1(x787)))
-	var x790 uint64
-	var x791 uint64
-	x790, x791 = bits.Add64(x777, x774, uint64(p521Uint1(x789)))
-	var x792 uint64
-	var x793 uint64
-	x792, x793 = bits.Add64(x775, x772, uint64(p521Uint1(x791)))
-	var x794 uint64
-	var x795 uint64
-	x794, x795 = bits.Add64(x773, x770, uint64(p521Uint1(x793)))
-	var x796 uint64
-	var x797 uint64
-	x796, x797 = bits.Add64(x771, x768, uint64(p521Uint1(x795)))
-	var x798 uint64
-	var x799 uint64
-	x798, x799 = bits.Add64(x769, x766, uint64(p521Uint1(x797)))
-	x800 := (uint64(p521Uint1(x799)) + x767)
-	var x801 uint64
-	var x802 uint64
-	x801, x802 = bits.Add64(x747, x782, uint64(0x0))
-	var x803 uint64
-	var x804 uint64
-	x803, x804 = bits.Add64(x749, x784, uint64(p521Uint1(x802)))
-	var x805 uint64
-	var x806 uint64
-	x805, x806 = bits.Add64(x751, x786, uint64(p521Uint1(x804)))
-	var x807 uint64
-	var x808 uint64
-	x807, x808 = bits.Add64(x753, x788, uint64(p521Uint1(x806)))
-	var x809 uint64
-	var x810 uint64
-	x809, x810 = bits.Add64(x755, x790, uint64(p521Uint1(x808)))
-	var x811 uint64
-	var x812 uint64
-	x811, x812 = bits.Add64(x757, x792, uint64(p521Uint1(x810)))
-	var x813 uint64
-	var x814 uint64
-	x813, x814 = bits.Add64(x759, x794, uint64(p521Uint1(x812)))
-	var x815 uint64
-	var x816 uint64
-	x815, x816 = bits.Add64(x761, x796, uint64(p521Uint1(x814)))
-	var x817 uint64
-	var x818 uint64
-	x817, x818 = bits.Add64(x763, x798, uint64(p521Uint1(x816)))
-	var x819 uint64
-	var x820 uint64
-	x819, x820 = bits.Add64(x765, x800, uint64(p521Uint1(x818)))
-	var x821 uint64
-	var x822 uint64
-	x822, x821 = bits.Mul64(x801, 0x1ff)
-	var x823 uint64
-	var x824 uint64
-	x824, x823 = bits.Mul64(x801, 0xffffffffffffffff)
-	var x825 uint64
-	var x826 uint64
-	x826, x825 = bits.Mul64(x801, 0xffffffffffffffff)
-	var x827 uint64
-	var x828 uint64
-	x828, x827 = bits.Mul64(x801, 0xffffffffffffffff)
-	var x829 uint64
-	var x830 uint64
-	x830, x829 = bits.Mul64(x801, 0xffffffffffffffff)
-	var x831 uint64
-	var x832 uint64
-	x832, x831 = bits.Mul64(x801, 0xffffffffffffffff)
-	var x833 uint64
-	var x834 uint64
-	x834, x833 = bits.Mul64(x801, 0xffffffffffffffff)
-	var x835 uint64
-	var x836 uint64
-	x836, x835 = bits.Mul64(x801, 0xffffffffffffffff)
-	var x837 uint64
-	var x838 uint64
-	x838, x837 = bits.Mul64(x801, 0xffffffffffffffff)
-	var x839 uint64
-	var x840 uint64
-	x839, x840 = bits.Add64(x838, x835, uint64(0x0))
-	var x841 uint64
-	var x842 uint64
-	x841, x842 = bits.Add64(x836, x833, uint64(p521Uint1(x840)))
-	var x843 uint64
-	var x844 uint64
-	x843, x844 = bits.Add64(x834, x831, uint64(p521Uint1(x842)))
-	var x845 uint64
-	var x846 uint64
-	x845, x846 = bits.Add64(x832, x829, uint64(p521Uint1(x844)))
-	var x847 uint64
-	var x848 uint64
-	x847, x848 = bits.Add64(x830, x827, uint64(p521Uint1(x846)))
-	var x849 uint64
-	var x850 uint64
-	x849, x850 = bits.Add64(x828, x825, uint64(p521Uint1(x848)))
-	var x851 uint64
-	var x852 uint64
-	x851, x852 = bits.Add64(x826, x823, uint64(p521Uint1(x850)))
-	var x853 uint64
-	var x854 uint64
-	x853, x854 = bits.Add64(x824, x821, uint64(p521Uint1(x852)))
-	x855 := (uint64(p521Uint1(x854)) + x822)
-	var x857 uint64
-	_, x857 = bits.Add64(x801, x837, uint64(0x0))
-	var x858 uint64
-	var x859 uint64
-	x858, x859 = bits.Add64(x803, x839, uint64(p521Uint1(x857)))
-	var x860 uint64
-	var x861 uint64
-	x860, x861 = bits.Add64(x805, x841, uint64(p521Uint1(x859)))
-	var x862 uint64
-	var x863 uint64
-	x862, x863 = bits.Add64(x807, x843, uint64(p521Uint1(x861)))
-	var x864 uint64
-	var x865 uint64
-	x864, x865 = bits.Add64(x809, x845, uint64(p521Uint1(x863)))
-	var x866 uint64
-	var x867 uint64
-	x866, x867 = bits.Add64(x811, x847, uint64(p521Uint1(x865)))
-	var x868 uint64
-	var x869 uint64
-	x868, x869 = bits.Add64(x813, x849, uint64(p521Uint1(x867)))
-	var x870 uint64
-	var x871 uint64
-	x870, x871 = bits.Add64(x815, x851, uint64(p521Uint1(x869)))
-	var x872 uint64
-	var x873 uint64
-	x872, x873 = bits.Add64(x817, x853, uint64(p521Uint1(x871)))
-	var x874 uint64
-	var x875 uint64
-	x874, x875 = bits.Add64(x819, x855, uint64(p521Uint1(x873)))
-	x876 := (uint64(p521Uint1(x875)) + uint64(p521Uint1(x820)))
-	var x877 uint64
-	var x878 uint64
-	x878, x877 = bits.Mul64(x8, arg2[8])
-	var x879 uint64
-	var x880 uint64
-	x880, x879 = bits.Mul64(x8, arg2[7])
-	var x881 uint64
-	var x882 uint64
-	x882, x881 = bits.Mul64(x8, arg2[6])
-	var x883 uint64
-	var x884 uint64
-	x884, x883 = bits.Mul64(x8, arg2[5])
-	var x885 uint64
-	var x886 uint64
-	x886, x885 = bits.Mul64(x8, arg2[4])
-	var x887 uint64
-	var x888 uint64
-	x888, x887 = bits.Mul64(x8, arg2[3])
-	var x889 uint64
-	var x890 uint64
-	x890, x889 = bits.Mul64(x8, arg2[2])
-	var x891 uint64
-	var x892 uint64
-	x892, x891 = bits.Mul64(x8, arg2[1])
-	var x893 uint64
-	var x894 uint64
-	x894, x893 = bits.Mul64(x8, arg2[0])
-	var x895 uint64
-	var x896 uint64
-	x895, x896 = bits.Add64(x894, x891, uint64(0x0))
-	var x897 uint64
-	var x898 uint64
-	x897, x898 = bits.Add64(x892, x889, uint64(p521Uint1(x896)))
-	var x899 uint64
-	var x900 uint64
-	x899, x900 = bits.Add64(x890, x887, uint64(p521Uint1(x898)))
-	var x901 uint64
-	var x902 uint64
-	x901, x902 = bits.Add64(x888, x885, uint64(p521Uint1(x900)))
-	var x903 uint64
-	var x904 uint64
-	x903, x904 = bits.Add64(x886, x883, uint64(p521Uint1(x902)))
-	var x905 uint64
-	var x906 uint64
-	x905, x906 = bits.Add64(x884, x881, uint64(p521Uint1(x904)))
-	var x907 uint64
-	var x908 uint64
-	x907, x908 = bits.Add64(x882, x879, uint64(p521Uint1(x906)))
-	var x909 uint64
-	var x910 uint64
-	x909, x910 = bits.Add64(x880, x877, uint64(p521Uint1(x908)))
-	x911 := (uint64(p521Uint1(x910)) + x878)
-	var x912 uint64
-	var x913 uint64
-	x912, x913 = bits.Add64(x858, x893, uint64(0x0))
-	var x914 uint64
-	var x915 uint64
-	x914, x915 = bits.Add64(x860, x895, uint64(p521Uint1(x913)))
-	var x916 uint64
-	var x917 uint64
-	x916, x917 = bits.Add64(x862, x897, uint64(p521Uint1(x915)))
-	var x918 uint64
-	var x919 uint64
-	x918, x919 = bits.Add64(x864, x899, uint64(p521Uint1(x917)))
-	var x920 uint64
-	var x921 uint64
-	x920, x921 = bits.Add64(x866, x901, uint64(p521Uint1(x919)))
-	var x922 uint64
-	var x923 uint64
-	x922, x923 = bits.Add64(x868, x903, uint64(p521Uint1(x921)))
-	var x924 uint64
-	var x925 uint64
-	x924, x925 = bits.Add64(x870, x905, uint64(p521Uint1(x923)))
-	var x926 uint64
-	var x927 uint64
-	x926, x927 = bits.Add64(x872, x907, uint64(p521Uint1(x925)))
-	var x928 uint64
-	var x929 uint64
-	x928, x929 = bits.Add64(x874, x909, uint64(p521Uint1(x927)))
-	var x930 uint64
-	var x931 uint64
-	x930, x931 = bits.Add64(x876, x911, uint64(p521Uint1(x929)))
-	var x932 uint64
-	var x933 uint64
-	x933, x932 = bits.Mul64(x912, 0x1ff)
-	var x934 uint64
-	var x935 uint64
-	x935, x934 = bits.Mul64(x912, 0xffffffffffffffff)
-	var x936 uint64
-	var x937 uint64
-	x937, x936 = bits.Mul64(x912, 0xffffffffffffffff)
-	var x938 uint64
-	var x939 uint64
-	x939, x938 = bits.Mul64(x912, 0xffffffffffffffff)
-	var x940 uint64
-	var x941 uint64
-	x941, x940 = bits.Mul64(x912, 0xffffffffffffffff)
-	var x942 uint64
-	var x943 uint64
-	x943, x942 = bits.Mul64(x912, 0xffffffffffffffff)
-	var x944 uint64
-	var x945 uint64
-	x945, x944 = bits.Mul64(x912, 0xffffffffffffffff)
-	var x946 uint64
-	var x947 uint64
-	x947, x946 = bits.Mul64(x912, 0xffffffffffffffff)
-	var x948 uint64
-	var x949 uint64
-	x949, x948 = bits.Mul64(x912, 0xffffffffffffffff)
-	var x950 uint64
-	var x951 uint64
-	x950, x951 = bits.Add64(x949, x946, uint64(0x0))
-	var x952 uint64
-	var x953 uint64
-	x952, x953 = bits.Add64(x947, x944, uint64(p521Uint1(x951)))
-	var x954 uint64
-	var x955 uint64
-	x954, x955 = bits.Add64(x945, x942, uint64(p521Uint1(x953)))
-	var x956 uint64
-	var x957 uint64
-	x956, x957 = bits.Add64(x943, x940, uint64(p521Uint1(x955)))
-	var x958 uint64
-	var x959 uint64
-	x958, x959 = bits.Add64(x941, x938, uint64(p521Uint1(x957)))
-	var x960 uint64
-	var x961 uint64
-	x960, x961 = bits.Add64(x939, x936, uint64(p521Uint1(x959)))
-	var x962 uint64
-	var x963 uint64
-	x962, x963 = bits.Add64(x937, x934, uint64(p521Uint1(x961)))
-	var x964 uint64
-	var x965 uint64
-	x964, x965 = bits.Add64(x935, x932, uint64(p521Uint1(x963)))
-	x966 := (uint64(p521Uint1(x965)) + x933)
-	var x968 uint64
-	_, x968 = bits.Add64(x912, x948, uint64(0x0))
-	var x969 uint64
-	var x970 uint64
-	x969, x970 = bits.Add64(x914, x950, uint64(p521Uint1(x968)))
-	var x971 uint64
-	var x972 uint64
-	x971, x972 = bits.Add64(x916, x952, uint64(p521Uint1(x970)))
-	var x973 uint64
-	var x974 uint64
-	x973, x974 = bits.Add64(x918, x954, uint64(p521Uint1(x972)))
-	var x975 uint64
-	var x976 uint64
-	x975, x976 = bits.Add64(x920, x956, uint64(p521Uint1(x974)))
-	var x977 uint64
-	var x978 uint64
-	x977, x978 = bits.Add64(x922, x958, uint64(p521Uint1(x976)))
-	var x979 uint64
-	var x980 uint64
-	x979, x980 = bits.Add64(x924, x960, uint64(p521Uint1(x978)))
-	var x981 uint64
-	var x982 uint64
-	x981, x982 = bits.Add64(x926, x962, uint64(p521Uint1(x980)))
-	var x983 uint64
-	var x984 uint64
-	x983, x984 = bits.Add64(x928, x964, uint64(p521Uint1(x982)))
-	var x985 uint64
-	var x986 uint64
-	x985, x986 = bits.Add64(x930, x966, uint64(p521Uint1(x984)))
-	x987 := (uint64(p521Uint1(x986)) + uint64(p521Uint1(x931)))
-	var x988 uint64
-	var x989 uint64
-	x988, x989 = bits.Sub64(x969, 0xffffffffffffffff, uint64(0x0))
-	var x990 uint64
-	var x991 uint64
-	x990, x991 = bits.Sub64(x971, 0xffffffffffffffff, uint64(p521Uint1(x989)))
-	var x992 uint64
-	var x993 uint64
-	x992, x993 = bits.Sub64(x973, 0xffffffffffffffff, uint64(p521Uint1(x991)))
-	var x994 uint64
-	var x995 uint64
-	x994, x995 = bits.Sub64(x975, 0xffffffffffffffff, uint64(p521Uint1(x993)))
-	var x996 uint64
-	var x997 uint64
-	x996, x997 = bits.Sub64(x977, 0xffffffffffffffff, uint64(p521Uint1(x995)))
-	var x998 uint64
-	var x999 uint64
-	x998, x999 = bits.Sub64(x979, 0xffffffffffffffff, uint64(p521Uint1(x997)))
-	var x1000 uint64
-	var x1001 uint64
-	x1000, x1001 = bits.Sub64(x981, 0xffffffffffffffff, uint64(p521Uint1(x999)))
-	var x1002 uint64
-	var x1003 uint64
-	x1002, x1003 = bits.Sub64(x983, 0xffffffffffffffff, uint64(p521Uint1(x1001)))
-	var x1004 uint64
-	var x1005 uint64
-	x1004, x1005 = bits.Sub64(x985, 0x1ff, uint64(p521Uint1(x1003)))
-	var x1007 uint64
-	_, x1007 = bits.Sub64(x987, uint64(0x0), uint64(p521Uint1(x1005)))
-	var x1008 uint64
-	p521CmovznzU64(&x1008, p521Uint1(x1007), x988, x969)
-	var x1009 uint64
-	p521CmovznzU64(&x1009, p521Uint1(x1007), x990, x971)
-	var x1010 uint64
-	p521CmovznzU64(&x1010, p521Uint1(x1007), x992, x973)
-	var x1011 uint64
-	p521CmovznzU64(&x1011, p521Uint1(x1007), x994, x975)
-	var x1012 uint64
-	p521CmovznzU64(&x1012, p521Uint1(x1007), x996, x977)
-	var x1013 uint64
-	p521CmovznzU64(&x1013, p521Uint1(x1007), x998, x979)
-	var x1014 uint64
-	p521CmovznzU64(&x1014, p521Uint1(x1007), x1000, x981)
-	var x1015 uint64
-	p521CmovznzU64(&x1015, p521Uint1(x1007), x1002, x983)
-	var x1016 uint64
-	p521CmovznzU64(&x1016, p521Uint1(x1007), x1004, x985)
-	out1[0] = x1008
-	out1[1] = x1009
-	out1[2] = x1010
-	out1[3] = x1011
-	out1[4] = x1012
-	out1[5] = x1013
-	out1[6] = x1014
-	out1[7] = x1015
-	out1[8] = x1016
-}
-
-// p521Square squares a field element in the Montgomery domain.
-//
-// Preconditions:
-//   0 ≤ eval arg1 < m
-// Postconditions:
-//   eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) * eval (from_montgomery arg1)) mod m
-//   0 ≤ eval out1 < m
-//
-func p521Square(out1 *p521MontgomeryDomainFieldElement, arg1 *p521MontgomeryDomainFieldElement) {
-	x1 := arg1[1]
-	x2 := arg1[2]
-	x3 := arg1[3]
-	x4 := arg1[4]
-	x5 := arg1[5]
-	x6 := arg1[6]
-	x7 := arg1[7]
-	x8 := arg1[8]
-	x9 := arg1[0]
-	var x10 uint64
-	var x11 uint64
-	x11, x10 = bits.Mul64(x9, arg1[8])
-	var x12 uint64
-	var x13 uint64
-	x13, x12 = bits.Mul64(x9, arg1[7])
-	var x14 uint64
-	var x15 uint64
-	x15, x14 = bits.Mul64(x9, arg1[6])
-	var x16 uint64
-	var x17 uint64
-	x17, x16 = bits.Mul64(x9, arg1[5])
-	var x18 uint64
-	var x19 uint64
-	x19, x18 = bits.Mul64(x9, arg1[4])
-	var x20 uint64
-	var x21 uint64
-	x21, x20 = bits.Mul64(x9, arg1[3])
-	var x22 uint64
-	var x23 uint64
-	x23, x22 = bits.Mul64(x9, arg1[2])
-	var x24 uint64
-	var x25 uint64
-	x25, x24 = bits.Mul64(x9, arg1[1])
-	var x26 uint64
-	var x27 uint64
-	x27, x26 = bits.Mul64(x9, arg1[0])
-	var x28 uint64
-	var x29 uint64
-	x28, x29 = bits.Add64(x27, x24, uint64(0x0))
-	var x30 uint64
-	var x31 uint64
-	x30, x31 = bits.Add64(x25, x22, uint64(p521Uint1(x29)))
-	var x32 uint64
-	var x33 uint64
-	x32, x33 = bits.Add64(x23, x20, uint64(p521Uint1(x31)))
-	var x34 uint64
-	var x35 uint64
-	x34, x35 = bits.Add64(x21, x18, uint64(p521Uint1(x33)))
-	var x36 uint64
-	var x37 uint64
-	x36, x37 = bits.Add64(x19, x16, uint64(p521Uint1(x35)))
-	var x38 uint64
-	var x39 uint64
-	x38, x39 = bits.Add64(x17, x14, uint64(p521Uint1(x37)))
-	var x40 uint64
-	var x41 uint64
-	x40, x41 = bits.Add64(x15, x12, uint64(p521Uint1(x39)))
-	var x42 uint64
-	var x43 uint64
-	x42, x43 = bits.Add64(x13, x10, uint64(p521Uint1(x41)))
-	x44 := (uint64(p521Uint1(x43)) + x11)
-	var x45 uint64
-	var x46 uint64
-	x46, x45 = bits.Mul64(x26, 0x1ff)
-	var x47 uint64
-	var x48 uint64
-	x48, x47 = bits.Mul64(x26, 0xffffffffffffffff)
-	var x49 uint64
-	var x50 uint64
-	x50, x49 = bits.Mul64(x26, 0xffffffffffffffff)
-	var x51 uint64
-	var x52 uint64
-	x52, x51 = bits.Mul64(x26, 0xffffffffffffffff)
-	var x53 uint64
-	var x54 uint64
-	x54, x53 = bits.Mul64(x26, 0xffffffffffffffff)
-	var x55 uint64
-	var x56 uint64
-	x56, x55 = bits.Mul64(x26, 0xffffffffffffffff)
-	var x57 uint64
-	var x58 uint64
-	x58, x57 = bits.Mul64(x26, 0xffffffffffffffff)
-	var x59 uint64
-	var x60 uint64
-	x60, x59 = bits.Mul64(x26, 0xffffffffffffffff)
-	var x61 uint64
-	var x62 uint64
-	x62, x61 = bits.Mul64(x26, 0xffffffffffffffff)
-	var x63 uint64
-	var x64 uint64
-	x63, x64 = bits.Add64(x62, x59, uint64(0x0))
-	var x65 uint64
-	var x66 uint64
-	x65, x66 = bits.Add64(x60, x57, uint64(p521Uint1(x64)))
-	var x67 uint64
-	var x68 uint64
-	x67, x68 = bits.Add64(x58, x55, uint64(p521Uint1(x66)))
-	var x69 uint64
-	var x70 uint64
-	x69, x70 = bits.Add64(x56, x53, uint64(p521Uint1(x68)))
-	var x71 uint64
-	var x72 uint64
-	x71, x72 = bits.Add64(x54, x51, uint64(p521Uint1(x70)))
-	var x73 uint64
-	var x74 uint64
-	x73, x74 = bits.Add64(x52, x49, uint64(p521Uint1(x72)))
-	var x75 uint64
-	var x76 uint64
-	x75, x76 = bits.Add64(x50, x47, uint64(p521Uint1(x74)))
-	var x77 uint64
-	var x78 uint64
-	x77, x78 = bits.Add64(x48, x45, uint64(p521Uint1(x76)))
-	x79 := (uint64(p521Uint1(x78)) + x46)
-	var x81 uint64
-	_, x81 = bits.Add64(x26, x61, uint64(0x0))
-	var x82 uint64
-	var x83 uint64
-	x82, x83 = bits.Add64(x28, x63, uint64(p521Uint1(x81)))
-	var x84 uint64
-	var x85 uint64
-	x84, x85 = bits.Add64(x30, x65, uint64(p521Uint1(x83)))
-	var x86 uint64
-	var x87 uint64
-	x86, x87 = bits.Add64(x32, x67, uint64(p521Uint1(x85)))
-	var x88 uint64
-	var x89 uint64
-	x88, x89 = bits.Add64(x34, x69, uint64(p521Uint1(x87)))
-	var x90 uint64
-	var x91 uint64
-	x90, x91 = bits.Add64(x36, x71, uint64(p521Uint1(x89)))
-	var x92 uint64
-	var x93 uint64
-	x92, x93 = bits.Add64(x38, x73, uint64(p521Uint1(x91)))
-	var x94 uint64
-	var x95 uint64
-	x94, x95 = bits.Add64(x40, x75, uint64(p521Uint1(x93)))
-	var x96 uint64
-	var x97 uint64
-	x96, x97 = bits.Add64(x42, x77, uint64(p521Uint1(x95)))
-	var x98 uint64
-	var x99 uint64
-	x98, x99 = bits.Add64(x44, x79, uint64(p521Uint1(x97)))
-	var x100 uint64
-	var x101 uint64
-	x101, x100 = bits.Mul64(x1, arg1[8])
-	var x102 uint64
-	var x103 uint64
-	x103, x102 = bits.Mul64(x1, arg1[7])
-	var x104 uint64
-	var x105 uint64
-	x105, x104 = bits.Mul64(x1, arg1[6])
-	var x106 uint64
-	var x107 uint64
-	x107, x106 = bits.Mul64(x1, arg1[5])
-	var x108 uint64
-	var x109 uint64
-	x109, x108 = bits.Mul64(x1, arg1[4])
-	var x110 uint64
-	var x111 uint64
-	x111, x110 = bits.Mul64(x1, arg1[3])
-	var x112 uint64
-	var x113 uint64
-	x113, x112 = bits.Mul64(x1, arg1[2])
-	var x114 uint64
-	var x115 uint64
-	x115, x114 = bits.Mul64(x1, arg1[1])
-	var x116 uint64
-	var x117 uint64
-	x117, x116 = bits.Mul64(x1, arg1[0])
-	var x118 uint64
-	var x119 uint64
-	x118, x119 = bits.Add64(x117, x114, uint64(0x0))
-	var x120 uint64
-	var x121 uint64
-	x120, x121 = bits.Add64(x115, x112, uint64(p521Uint1(x119)))
-	var x122 uint64
-	var x123 uint64
-	x122, x123 = bits.Add64(x113, x110, uint64(p521Uint1(x121)))
-	var x124 uint64
-	var x125 uint64
-	x124, x125 = bits.Add64(x111, x108, uint64(p521Uint1(x123)))
-	var x126 uint64
-	var x127 uint64
-	x126, x127 = bits.Add64(x109, x106, uint64(p521Uint1(x125)))
-	var x128 uint64
-	var x129 uint64
-	x128, x129 = bits.Add64(x107, x104, uint64(p521Uint1(x127)))
-	var x130 uint64
-	var x131 uint64
-	x130, x131 = bits.Add64(x105, x102, uint64(p521Uint1(x129)))
-	var x132 uint64
-	var x133 uint64
-	x132, x133 = bits.Add64(x103, x100, uint64(p521Uint1(x131)))
-	x134 := (uint64(p521Uint1(x133)) + x101)
-	var x135 uint64
-	var x136 uint64
-	x135, x136 = bits.Add64(x82, x116, uint64(0x0))
-	var x137 uint64
-	var x138 uint64
-	x137, x138 = bits.Add64(x84, x118, uint64(p521Uint1(x136)))
-	var x139 uint64
-	var x140 uint64
-	x139, x140 = bits.Add64(x86, x120, uint64(p521Uint1(x138)))
-	var x141 uint64
-	var x142 uint64
-	x141, x142 = bits.Add64(x88, x122, uint64(p521Uint1(x140)))
-	var x143 uint64
-	var x144 uint64
-	x143, x144 = bits.Add64(x90, x124, uint64(p521Uint1(x142)))
-	var x145 uint64
-	var x146 uint64
-	x145, x146 = bits.Add64(x92, x126, uint64(p521Uint1(x144)))
-	var x147 uint64
-	var x148 uint64
-	x147, x148 = bits.Add64(x94, x128, uint64(p521Uint1(x146)))
-	var x149 uint64
-	var x150 uint64
-	x149, x150 = bits.Add64(x96, x130, uint64(p521Uint1(x148)))
-	var x151 uint64
-	var x152 uint64
-	x151, x152 = bits.Add64(x98, x132, uint64(p521Uint1(x150)))
-	var x153 uint64
-	var x154 uint64
-	x153, x154 = bits.Add64(uint64(p521Uint1(x99)), x134, uint64(p521Uint1(x152)))
-	var x155 uint64
-	var x156 uint64
-	x156, x155 = bits.Mul64(x135, 0x1ff)
-	var x157 uint64
-	var x158 uint64
-	x158, x157 = bits.Mul64(x135, 0xffffffffffffffff)
-	var x159 uint64
-	var x160 uint64
-	x160, x159 = bits.Mul64(x135, 0xffffffffffffffff)
-	var x161 uint64
-	var x162 uint64
-	x162, x161 = bits.Mul64(x135, 0xffffffffffffffff)
-	var x163 uint64
-	var x164 uint64
-	x164, x163 = bits.Mul64(x135, 0xffffffffffffffff)
-	var x165 uint64
-	var x166 uint64
-	x166, x165 = bits.Mul64(x135, 0xffffffffffffffff)
-	var x167 uint64
-	var x168 uint64
-	x168, x167 = bits.Mul64(x135, 0xffffffffffffffff)
-	var x169 uint64
-	var x170 uint64
-	x170, x169 = bits.Mul64(x135, 0xffffffffffffffff)
-	var x171 uint64
-	var x172 uint64
-	x172, x171 = bits.Mul64(x135, 0xffffffffffffffff)
-	var x173 uint64
-	var x174 uint64
-	x173, x174 = bits.Add64(x172, x169, uint64(0x0))
-	var x175 uint64
-	var x176 uint64
-	x175, x176 = bits.Add64(x170, x167, uint64(p521Uint1(x174)))
-	var x177 uint64
-	var x178 uint64
-	x177, x178 = bits.Add64(x168, x165, uint64(p521Uint1(x176)))
-	var x179 uint64
-	var x180 uint64
-	x179, x180 = bits.Add64(x166, x163, uint64(p521Uint1(x178)))
-	var x181 uint64
-	var x182 uint64
-	x181, x182 = bits.Add64(x164, x161, uint64(p521Uint1(x180)))
-	var x183 uint64
-	var x184 uint64
-	x183, x184 = bits.Add64(x162, x159, uint64(p521Uint1(x182)))
-	var x185 uint64
-	var x186 uint64
-	x185, x186 = bits.Add64(x160, x157, uint64(p521Uint1(x184)))
-	var x187 uint64
-	var x188 uint64
-	x187, x188 = bits.Add64(x158, x155, uint64(p521Uint1(x186)))
-	x189 := (uint64(p521Uint1(x188)) + x156)
-	var x191 uint64
-	_, x191 = bits.Add64(x135, x171, uint64(0x0))
-	var x192 uint64
-	var x193 uint64
-	x192, x193 = bits.Add64(x137, x173, uint64(p521Uint1(x191)))
-	var x194 uint64
-	var x195 uint64
-	x194, x195 = bits.Add64(x139, x175, uint64(p521Uint1(x193)))
-	var x196 uint64
-	var x197 uint64
-	x196, x197 = bits.Add64(x141, x177, uint64(p521Uint1(x195)))
-	var x198 uint64
-	var x199 uint64
-	x198, x199 = bits.Add64(x143, x179, uint64(p521Uint1(x197)))
-	var x200 uint64
-	var x201 uint64
-	x200, x201 = bits.Add64(x145, x181, uint64(p521Uint1(x199)))
-	var x202 uint64
-	var x203 uint64
-	x202, x203 = bits.Add64(x147, x183, uint64(p521Uint1(x201)))
-	var x204 uint64
-	var x205 uint64
-	x204, x205 = bits.Add64(x149, x185, uint64(p521Uint1(x203)))
-	var x206 uint64
-	var x207 uint64
-	x206, x207 = bits.Add64(x151, x187, uint64(p521Uint1(x205)))
-	var x208 uint64
-	var x209 uint64
-	x208, x209 = bits.Add64(x153, x189, uint64(p521Uint1(x207)))
-	x210 := (uint64(p521Uint1(x209)) + uint64(p521Uint1(x154)))
-	var x211 uint64
-	var x212 uint64
-	x212, x211 = bits.Mul64(x2, arg1[8])
-	var x213 uint64
-	var x214 uint64
-	x214, x213 = bits.Mul64(x2, arg1[7])
-	var x215 uint64
-	var x216 uint64
-	x216, x215 = bits.Mul64(x2, arg1[6])
-	var x217 uint64
-	var x218 uint64
-	x218, x217 = bits.Mul64(x2, arg1[5])
-	var x219 uint64
-	var x220 uint64
-	x220, x219 = bits.Mul64(x2, arg1[4])
-	var x221 uint64
-	var x222 uint64
-	x222, x221 = bits.Mul64(x2, arg1[3])
-	var x223 uint64
-	var x224 uint64
-	x224, x223 = bits.Mul64(x2, arg1[2])
-	var x225 uint64
-	var x226 uint64
-	x226, x225 = bits.Mul64(x2, arg1[1])
-	var x227 uint64
-	var x228 uint64
-	x228, x227 = bits.Mul64(x2, arg1[0])
-	var x229 uint64
-	var x230 uint64
-	x229, x230 = bits.Add64(x228, x225, uint64(0x0))
-	var x231 uint64
-	var x232 uint64
-	x231, x232 = bits.Add64(x226, x223, uint64(p521Uint1(x230)))
-	var x233 uint64
-	var x234 uint64
-	x233, x234 = bits.Add64(x224, x221, uint64(p521Uint1(x232)))
-	var x235 uint64
-	var x236 uint64
-	x235, x236 = bits.Add64(x222, x219, uint64(p521Uint1(x234)))
-	var x237 uint64
-	var x238 uint64
-	x237, x238 = bits.Add64(x220, x217, uint64(p521Uint1(x236)))
-	var x239 uint64
-	var x240 uint64
-	x239, x240 = bits.Add64(x218, x215, uint64(p521Uint1(x238)))
-	var x241 uint64
-	var x242 uint64
-	x241, x242 = bits.Add64(x216, x213, uint64(p521Uint1(x240)))
-	var x243 uint64
-	var x244 uint64
-	x243, x244 = bits.Add64(x214, x211, uint64(p521Uint1(x242)))
-	x245 := (uint64(p521Uint1(x244)) + x212)
-	var x246 uint64
-	var x247 uint64
-	x246, x247 = bits.Add64(x192, x227, uint64(0x0))
-	var x248 uint64
-	var x249 uint64
-	x248, x249 = bits.Add64(x194, x229, uint64(p521Uint1(x247)))
-	var x250 uint64
-	var x251 uint64
-	x250, x251 = bits.Add64(x196, x231, uint64(p521Uint1(x249)))
-	var x252 uint64
-	var x253 uint64
-	x252, x253 = bits.Add64(x198, x233, uint64(p521Uint1(x251)))
-	var x254 uint64
-	var x255 uint64
-	x254, x255 = bits.Add64(x200, x235, uint64(p521Uint1(x253)))
-	var x256 uint64
-	var x257 uint64
-	x256, x257 = bits.Add64(x202, x237, uint64(p521Uint1(x255)))
-	var x258 uint64
-	var x259 uint64
-	x258, x259 = bits.Add64(x204, x239, uint64(p521Uint1(x257)))
-	var x260 uint64
-	var x261 uint64
-	x260, x261 = bits.Add64(x206, x241, uint64(p521Uint1(x259)))
-	var x262 uint64
-	var x263 uint64
-	x262, x263 = bits.Add64(x208, x243, uint64(p521Uint1(x261)))
-	var x264 uint64
-	var x265 uint64
-	x264, x265 = bits.Add64(x210, x245, uint64(p521Uint1(x263)))
-	var x266 uint64
-	var x267 uint64
-	x267, x266 = bits.Mul64(x246, 0x1ff)
-	var x268 uint64
-	var x269 uint64
-	x269, x268 = bits.Mul64(x246, 0xffffffffffffffff)
-	var x270 uint64
-	var x271 uint64
-	x271, x270 = bits.Mul64(x246, 0xffffffffffffffff)
-	var x272 uint64
-	var x273 uint64
-	x273, x272 = bits.Mul64(x246, 0xffffffffffffffff)
-	var x274 uint64
-	var x275 uint64
-	x275, x274 = bits.Mul64(x246, 0xffffffffffffffff)
-	var x276 uint64
-	var x277 uint64
-	x277, x276 = bits.Mul64(x246, 0xffffffffffffffff)
-	var x278 uint64
-	var x279 uint64
-	x279, x278 = bits.Mul64(x246, 0xffffffffffffffff)
-	var x280 uint64
-	var x281 uint64
-	x281, x280 = bits.Mul64(x246, 0xffffffffffffffff)
-	var x282 uint64
-	var x283 uint64
-	x283, x282 = bits.Mul64(x246, 0xffffffffffffffff)
-	var x284 uint64
-	var x285 uint64
-	x284, x285 = bits.Add64(x283, x280, uint64(0x0))
-	var x286 uint64
-	var x287 uint64
-	x286, x287 = bits.Add64(x281, x278, uint64(p521Uint1(x285)))
-	var x288 uint64
-	var x289 uint64
-	x288, x289 = bits.Add64(x279, x276, uint64(p521Uint1(x287)))
-	var x290 uint64
-	var x291 uint64
-	x290, x291 = bits.Add64(x277, x274, uint64(p521Uint1(x289)))
-	var x292 uint64
-	var x293 uint64
-	x292, x293 = bits.Add64(x275, x272, uint64(p521Uint1(x291)))
-	var x294 uint64
-	var x295 uint64
-	x294, x295 = bits.Add64(x273, x270, uint64(p521Uint1(x293)))
-	var x296 uint64
-	var x297 uint64
-	x296, x297 = bits.Add64(x271, x268, uint64(p521Uint1(x295)))
-	var x298 uint64
-	var x299 uint64
-	x298, x299 = bits.Add64(x269, x266, uint64(p521Uint1(x297)))
-	x300 := (uint64(p521Uint1(x299)) + x267)
-	var x302 uint64
-	_, x302 = bits.Add64(x246, x282, uint64(0x0))
-	var x303 uint64
-	var x304 uint64
-	x303, x304 = bits.Add64(x248, x284, uint64(p521Uint1(x302)))
-	var x305 uint64
-	var x306 uint64
-	x305, x306 = bits.Add64(x250, x286, uint64(p521Uint1(x304)))
-	var x307 uint64
-	var x308 uint64
-	x307, x308 = bits.Add64(x252, x288, uint64(p521Uint1(x306)))
-	var x309 uint64
-	var x310 uint64
-	x309, x310 = bits.Add64(x254, x290, uint64(p521Uint1(x308)))
-	var x311 uint64
-	var x312 uint64
-	x311, x312 = bits.Add64(x256, x292, uint64(p521Uint1(x310)))
-	var x313 uint64
-	var x314 uint64
-	x313, x314 = bits.Add64(x258, x294, uint64(p521Uint1(x312)))
-	var x315 uint64
-	var x316 uint64
-	x315, x316 = bits.Add64(x260, x296, uint64(p521Uint1(x314)))
-	var x317 uint64
-	var x318 uint64
-	x317, x318 = bits.Add64(x262, x298, uint64(p521Uint1(x316)))
-	var x319 uint64
-	var x320 uint64
-	x319, x320 = bits.Add64(x264, x300, uint64(p521Uint1(x318)))
-	x321 := (uint64(p521Uint1(x320)) + uint64(p521Uint1(x265)))
-	var x322 uint64
-	var x323 uint64
-	x323, x322 = bits.Mul64(x3, arg1[8])
-	var x324 uint64
-	var x325 uint64
-	x325, x324 = bits.Mul64(x3, arg1[7])
-	var x326 uint64
-	var x327 uint64
-	x327, x326 = bits.Mul64(x3, arg1[6])
-	var x328 uint64
-	var x329 uint64
-	x329, x328 = bits.Mul64(x3, arg1[5])
-	var x330 uint64
-	var x331 uint64
-	x331, x330 = bits.Mul64(x3, arg1[4])
-	var x332 uint64
-	var x333 uint64
-	x333, x332 = bits.Mul64(x3, arg1[3])
-	var x334 uint64
-	var x335 uint64
-	x335, x334 = bits.Mul64(x3, arg1[2])
-	var x336 uint64
-	var x337 uint64
-	x337, x336 = bits.Mul64(x3, arg1[1])
-	var x338 uint64
-	var x339 uint64
-	x339, x338 = bits.Mul64(x3, arg1[0])
-	var x340 uint64
-	var x341 uint64
-	x340, x341 = bits.Add64(x339, x336, uint64(0x0))
-	var x342 uint64
-	var x343 uint64
-	x342, x343 = bits.Add64(x337, x334, uint64(p521Uint1(x341)))
-	var x344 uint64
-	var x345 uint64
-	x344, x345 = bits.Add64(x335, x332, uint64(p521Uint1(x343)))
-	var x346 uint64
-	var x347 uint64
-	x346, x347 = bits.Add64(x333, x330, uint64(p521Uint1(x345)))
-	var x348 uint64
-	var x349 uint64
-	x348, x349 = bits.Add64(x331, x328, uint64(p521Uint1(x347)))
-	var x350 uint64
-	var x351 uint64
-	x350, x351 = bits.Add64(x329, x326, uint64(p521Uint1(x349)))
-	var x352 uint64
-	var x353 uint64
-	x352, x353 = bits.Add64(x327, x324, uint64(p521Uint1(x351)))
-	var x354 uint64
-	var x355 uint64
-	x354, x355 = bits.Add64(x325, x322, uint64(p521Uint1(x353)))
-	x356 := (uint64(p521Uint1(x355)) + x323)
-	var x357 uint64
-	var x358 uint64
-	x357, x358 = bits.Add64(x303, x338, uint64(0x0))
-	var x359 uint64
-	var x360 uint64
-	x359, x360 = bits.Add64(x305, x340, uint64(p521Uint1(x358)))
-	var x361 uint64
-	var x362 uint64
-	x361, x362 = bits.Add64(x307, x342, uint64(p521Uint1(x360)))
-	var x363 uint64
-	var x364 uint64
-	x363, x364 = bits.Add64(x309, x344, uint64(p521Uint1(x362)))
-	var x365 uint64
-	var x366 uint64
-	x365, x366 = bits.Add64(x311, x346, uint64(p521Uint1(x364)))
-	var x367 uint64
-	var x368 uint64
-	x367, x368 = bits.Add64(x313, x348, uint64(p521Uint1(x366)))
-	var x369 uint64
-	var x370 uint64
-	x369, x370 = bits.Add64(x315, x350, uint64(p521Uint1(x368)))
-	var x371 uint64
-	var x372 uint64
-	x371, x372 = bits.Add64(x317, x352, uint64(p521Uint1(x370)))
-	var x373 uint64
-	var x374 uint64
-	x373, x374 = bits.Add64(x319, x354, uint64(p521Uint1(x372)))
-	var x375 uint64
-	var x376 uint64
-	x375, x376 = bits.Add64(x321, x356, uint64(p521Uint1(x374)))
-	var x377 uint64
-	var x378 uint64
-	x378, x377 = bits.Mul64(x357, 0x1ff)
-	var x379 uint64
-	var x380 uint64
-	x380, x379 = bits.Mul64(x357, 0xffffffffffffffff)
-	var x381 uint64
-	var x382 uint64
-	x382, x381 = bits.Mul64(x357, 0xffffffffffffffff)
-	var x383 uint64
-	var x384 uint64
-	x384, x383 = bits.Mul64(x357, 0xffffffffffffffff)
-	var x385 uint64
-	var x386 uint64
-	x386, x385 = bits.Mul64(x357, 0xffffffffffffffff)
-	var x387 uint64
-	var x388 uint64
-	x388, x387 = bits.Mul64(x357, 0xffffffffffffffff)
-	var x389 uint64
-	var x390 uint64
-	x390, x389 = bits.Mul64(x357, 0xffffffffffffffff)
-	var x391 uint64
-	var x392 uint64
-	x392, x391 = bits.Mul64(x357, 0xffffffffffffffff)
-	var x393 uint64
-	var x394 uint64
-	x394, x393 = bits.Mul64(x357, 0xffffffffffffffff)
-	var x395 uint64
-	var x396 uint64
-	x395, x396 = bits.Add64(x394, x391, uint64(0x0))
-	var x397 uint64
-	var x398 uint64
-	x397, x398 = bits.Add64(x392, x389, uint64(p521Uint1(x396)))
-	var x399 uint64
-	var x400 uint64
-	x399, x400 = bits.Add64(x390, x387, uint64(p521Uint1(x398)))
-	var x401 uint64
-	var x402 uint64
-	x401, x402 = bits.Add64(x388, x385, uint64(p521Uint1(x400)))
-	var x403 uint64
-	var x404 uint64
-	x403, x404 = bits.Add64(x386, x383, uint64(p521Uint1(x402)))
-	var x405 uint64
-	var x406 uint64
-	x405, x406 = bits.Add64(x384, x381, uint64(p521Uint1(x404)))
-	var x407 uint64
-	var x408 uint64
-	x407, x408 = bits.Add64(x382, x379, uint64(p521Uint1(x406)))
-	var x409 uint64
-	var x410 uint64
-	x409, x410 = bits.Add64(x380, x377, uint64(p521Uint1(x408)))
-	x411 := (uint64(p521Uint1(x410)) + x378)
-	var x413 uint64
-	_, x413 = bits.Add64(x357, x393, uint64(0x0))
-	var x414 uint64
-	var x415 uint64
-	x414, x415 = bits.Add64(x359, x395, uint64(p521Uint1(x413)))
-	var x416 uint64
-	var x417 uint64
-	x416, x417 = bits.Add64(x361, x397, uint64(p521Uint1(x415)))
-	var x418 uint64
-	var x419 uint64
-	x418, x419 = bits.Add64(x363, x399, uint64(p521Uint1(x417)))
-	var x420 uint64
-	var x421 uint64
-	x420, x421 = bits.Add64(x365, x401, uint64(p521Uint1(x419)))
-	var x422 uint64
-	var x423 uint64
-	x422, x423 = bits.Add64(x367, x403, uint64(p521Uint1(x421)))
-	var x424 uint64
-	var x425 uint64
-	x424, x425 = bits.Add64(x369, x405, uint64(p521Uint1(x423)))
-	var x426 uint64
-	var x427 uint64
-	x426, x427 = bits.Add64(x371, x407, uint64(p521Uint1(x425)))
-	var x428 uint64
-	var x429 uint64
-	x428, x429 = bits.Add64(x373, x409, uint64(p521Uint1(x427)))
-	var x430 uint64
-	var x431 uint64
-	x430, x431 = bits.Add64(x375, x411, uint64(p521Uint1(x429)))
-	x432 := (uint64(p521Uint1(x431)) + uint64(p521Uint1(x376)))
-	var x433 uint64
-	var x434 uint64
-	x434, x433 = bits.Mul64(x4, arg1[8])
-	var x435 uint64
-	var x436 uint64
-	x436, x435 = bits.Mul64(x4, arg1[7])
-	var x437 uint64
-	var x438 uint64
-	x438, x437 = bits.Mul64(x4, arg1[6])
-	var x439 uint64
-	var x440 uint64
-	x440, x439 = bits.Mul64(x4, arg1[5])
-	var x441 uint64
-	var x442 uint64
-	x442, x441 = bits.Mul64(x4, arg1[4])
-	var x443 uint64
-	var x444 uint64
-	x444, x443 = bits.Mul64(x4, arg1[3])
-	var x445 uint64
-	var x446 uint64
-	x446, x445 = bits.Mul64(x4, arg1[2])
-	var x447 uint64
-	var x448 uint64
-	x448, x447 = bits.Mul64(x4, arg1[1])
-	var x449 uint64
-	var x450 uint64
-	x450, x449 = bits.Mul64(x4, arg1[0])
-	var x451 uint64
-	var x452 uint64
-	x451, x452 = bits.Add64(x450, x447, uint64(0x0))
-	var x453 uint64
-	var x454 uint64
-	x453, x454 = bits.Add64(x448, x445, uint64(p521Uint1(x452)))
-	var x455 uint64
-	var x456 uint64
-	x455, x456 = bits.Add64(x446, x443, uint64(p521Uint1(x454)))
-	var x457 uint64
-	var x458 uint64
-	x457, x458 = bits.Add64(x444, x441, uint64(p521Uint1(x456)))
-	var x459 uint64
-	var x460 uint64
-	x459, x460 = bits.Add64(x442, x439, uint64(p521Uint1(x458)))
-	var x461 uint64
-	var x462 uint64
-	x461, x462 = bits.Add64(x440, x437, uint64(p521Uint1(x460)))
-	var x463 uint64
-	var x464 uint64
-	x463, x464 = bits.Add64(x438, x435, uint64(p521Uint1(x462)))
-	var x465 uint64
-	var x466 uint64
-	x465, x466 = bits.Add64(x436, x433, uint64(p521Uint1(x464)))
-	x467 := (uint64(p521Uint1(x466)) + x434)
-	var x468 uint64
-	var x469 uint64
-	x468, x469 = bits.Add64(x414, x449, uint64(0x0))
-	var x470 uint64
-	var x471 uint64
-	x470, x471 = bits.Add64(x416, x451, uint64(p521Uint1(x469)))
-	var x472 uint64
-	var x473 uint64
-	x472, x473 = bits.Add64(x418, x453, uint64(p521Uint1(x471)))
-	var x474 uint64
-	var x475 uint64
-	x474, x475 = bits.Add64(x420, x455, uint64(p521Uint1(x473)))
-	var x476 uint64
-	var x477 uint64
-	x476, x477 = bits.Add64(x422, x457, uint64(p521Uint1(x475)))
-	var x478 uint64
-	var x479 uint64
-	x478, x479 = bits.Add64(x424, x459, uint64(p521Uint1(x477)))
-	var x480 uint64
-	var x481 uint64
-	x480, x481 = bits.Add64(x426, x461, uint64(p521Uint1(x479)))
-	var x482 uint64
-	var x483 uint64
-	x482, x483 = bits.Add64(x428, x463, uint64(p521Uint1(x481)))
-	var x484 uint64
-	var x485 uint64
-	x484, x485 = bits.Add64(x430, x465, uint64(p521Uint1(x483)))
-	var x486 uint64
-	var x487 uint64
-	x486, x487 = bits.Add64(x432, x467, uint64(p521Uint1(x485)))
-	var x488 uint64
-	var x489 uint64
-	x489, x488 = bits.Mul64(x468, 0x1ff)
-	var x490 uint64
-	var x491 uint64
-	x491, x490 = bits.Mul64(x468, 0xffffffffffffffff)
-	var x492 uint64
-	var x493 uint64
-	x493, x492 = bits.Mul64(x468, 0xffffffffffffffff)
-	var x494 uint64
-	var x495 uint64
-	x495, x494 = bits.Mul64(x468, 0xffffffffffffffff)
-	var x496 uint64
-	var x497 uint64
-	x497, x496 = bits.Mul64(x468, 0xffffffffffffffff)
-	var x498 uint64
-	var x499 uint64
-	x499, x498 = bits.Mul64(x468, 0xffffffffffffffff)
-	var x500 uint64
-	var x501 uint64
-	x501, x500 = bits.Mul64(x468, 0xffffffffffffffff)
-	var x502 uint64
-	var x503 uint64
-	x503, x502 = bits.Mul64(x468, 0xffffffffffffffff)
-	var x504 uint64
-	var x505 uint64
-	x505, x504 = bits.Mul64(x468, 0xffffffffffffffff)
-	var x506 uint64
-	var x507 uint64
-	x506, x507 = bits.Add64(x505, x502, uint64(0x0))
-	var x508 uint64
-	var x509 uint64
-	x508, x509 = bits.Add64(x503, x500, uint64(p521Uint1(x507)))
-	var x510 uint64
-	var x511 uint64
-	x510, x511 = bits.Add64(x501, x498, uint64(p521Uint1(x509)))
-	var x512 uint64
-	var x513 uint64
-	x512, x513 = bits.Add64(x499, x496, uint64(p521Uint1(x511)))
-	var x514 uint64
-	var x515 uint64
-	x514, x515 = bits.Add64(x497, x494, uint64(p521Uint1(x513)))
-	var x516 uint64
-	var x517 uint64
-	x516, x517 = bits.Add64(x495, x492, uint64(p521Uint1(x515)))
-	var x518 uint64
-	var x519 uint64
-	x518, x519 = bits.Add64(x493, x490, uint64(p521Uint1(x517)))
-	var x520 uint64
-	var x521 uint64
-	x520, x521 = bits.Add64(x491, x488, uint64(p521Uint1(x519)))
-	x522 := (uint64(p521Uint1(x521)) + x489)
-	var x524 uint64
-	_, x524 = bits.Add64(x468, x504, uint64(0x0))
-	var x525 uint64
-	var x526 uint64
-	x525, x526 = bits.Add64(x470, x506, uint64(p521Uint1(x524)))
-	var x527 uint64
-	var x528 uint64
-	x527, x528 = bits.Add64(x472, x508, uint64(p521Uint1(x526)))
-	var x529 uint64
-	var x530 uint64
-	x529, x530 = bits.Add64(x474, x510, uint64(p521Uint1(x528)))
-	var x531 uint64
-	var x532 uint64
-	x531, x532 = bits.Add64(x476, x512, uint64(p521Uint1(x530)))
-	var x533 uint64
-	var x534 uint64
-	x533, x534 = bits.Add64(x478, x514, uint64(p521Uint1(x532)))
-	var x535 uint64
-	var x536 uint64
-	x535, x536 = bits.Add64(x480, x516, uint64(p521Uint1(x534)))
-	var x537 uint64
-	var x538 uint64
-	x537, x538 = bits.Add64(x482, x518, uint64(p521Uint1(x536)))
-	var x539 uint64
-	var x540 uint64
-	x539, x540 = bits.Add64(x484, x520, uint64(p521Uint1(x538)))
-	var x541 uint64
-	var x542 uint64
-	x541, x542 = bits.Add64(x486, x522, uint64(p521Uint1(x540)))
-	x543 := (uint64(p521Uint1(x542)) + uint64(p521Uint1(x487)))
-	var x544 uint64
-	var x545 uint64
-	x545, x544 = bits.Mul64(x5, arg1[8])
-	var x546 uint64
-	var x547 uint64
-	x547, x546 = bits.Mul64(x5, arg1[7])
-	var x548 uint64
-	var x549 uint64
-	x549, x548 = bits.Mul64(x5, arg1[6])
-	var x550 uint64
-	var x551 uint64
-	x551, x550 = bits.Mul64(x5, arg1[5])
-	var x552 uint64
-	var x553 uint64
-	x553, x552 = bits.Mul64(x5, arg1[4])
-	var x554 uint64
-	var x555 uint64
-	x555, x554 = bits.Mul64(x5, arg1[3])
-	var x556 uint64
-	var x557 uint64
-	x557, x556 = bits.Mul64(x5, arg1[2])
-	var x558 uint64
-	var x559 uint64
-	x559, x558 = bits.Mul64(x5, arg1[1])
-	var x560 uint64
-	var x561 uint64
-	x561, x560 = bits.Mul64(x5, arg1[0])
-	var x562 uint64
-	var x563 uint64
-	x562, x563 = bits.Add64(x561, x558, uint64(0x0))
-	var x564 uint64
-	var x565 uint64
-	x564, x565 = bits.Add64(x559, x556, uint64(p521Uint1(x563)))
-	var x566 uint64
-	var x567 uint64
-	x566, x567 = bits.Add64(x557, x554, uint64(p521Uint1(x565)))
-	var x568 uint64
-	var x569 uint64
-	x568, x569 = bits.Add64(x555, x552, uint64(p521Uint1(x567)))
-	var x570 uint64
-	var x571 uint64
-	x570, x571 = bits.Add64(x553, x550, uint64(p521Uint1(x569)))
-	var x572 uint64
-	var x573 uint64
-	x572, x573 = bits.Add64(x551, x548, uint64(p521Uint1(x571)))
-	var x574 uint64
-	var x575 uint64
-	x574, x575 = bits.Add64(x549, x546, uint64(p521Uint1(x573)))
-	var x576 uint64
-	var x577 uint64
-	x576, x577 = bits.Add64(x547, x544, uint64(p521Uint1(x575)))
-	x578 := (uint64(p521Uint1(x577)) + x545)
-	var x579 uint64
-	var x580 uint64
-	x579, x580 = bits.Add64(x525, x560, uint64(0x0))
-	var x581 uint64
-	var x582 uint64
-	x581, x582 = bits.Add64(x527, x562, uint64(p521Uint1(x580)))
-	var x583 uint64
-	var x584 uint64
-	x583, x584 = bits.Add64(x529, x564, uint64(p521Uint1(x582)))
-	var x585 uint64
-	var x586 uint64
-	x585, x586 = bits.Add64(x531, x566, uint64(p521Uint1(x584)))
-	var x587 uint64
-	var x588 uint64
-	x587, x588 = bits.Add64(x533, x568, uint64(p521Uint1(x586)))
-	var x589 uint64
-	var x590 uint64
-	x589, x590 = bits.Add64(x535, x570, uint64(p521Uint1(x588)))
-	var x591 uint64
-	var x592 uint64
-	x591, x592 = bits.Add64(x537, x572, uint64(p521Uint1(x590)))
-	var x593 uint64
-	var x594 uint64
-	x593, x594 = bits.Add64(x539, x574, uint64(p521Uint1(x592)))
-	var x595 uint64
-	var x596 uint64
-	x595, x596 = bits.Add64(x541, x576, uint64(p521Uint1(x594)))
-	var x597 uint64
-	var x598 uint64
-	x597, x598 = bits.Add64(x543, x578, uint64(p521Uint1(x596)))
-	var x599 uint64
-	var x600 uint64
-	x600, x599 = bits.Mul64(x579, 0x1ff)
-	var x601 uint64
-	var x602 uint64
-	x602, x601 = bits.Mul64(x579, 0xffffffffffffffff)
-	var x603 uint64
-	var x604 uint64
-	x604, x603 = bits.Mul64(x579, 0xffffffffffffffff)
-	var x605 uint64
-	var x606 uint64
-	x606, x605 = bits.Mul64(x579, 0xffffffffffffffff)
-	var x607 uint64
-	var x608 uint64
-	x608, x607 = bits.Mul64(x579, 0xffffffffffffffff)
-	var x609 uint64
-	var x610 uint64
-	x610, x609 = bits.Mul64(x579, 0xffffffffffffffff)
-	var x611 uint64
-	var x612 uint64
-	x612, x611 = bits.Mul64(x579, 0xffffffffffffffff)
-	var x613 uint64
-	var x614 uint64
-	x614, x613 = bits.Mul64(x579, 0xffffffffffffffff)
-	var x615 uint64
-	var x616 uint64
-	x616, x615 = bits.Mul64(x579, 0xffffffffffffffff)
-	var x617 uint64
-	var x618 uint64
-	x617, x618 = bits.Add64(x616, x613, uint64(0x0))
-	var x619 uint64
-	var x620 uint64
-	x619, x620 = bits.Add64(x614, x611, uint64(p521Uint1(x618)))
-	var x621 uint64
-	var x622 uint64
-	x621, x622 = bits.Add64(x612, x609, uint64(p521Uint1(x620)))
-	var x623 uint64
-	var x624 uint64
-	x623, x624 = bits.Add64(x610, x607, uint64(p521Uint1(x622)))
-	var x625 uint64
-	var x626 uint64
-	x625, x626 = bits.Add64(x608, x605, uint64(p521Uint1(x624)))
-	var x627 uint64
-	var x628 uint64
-	x627, x628 = bits.Add64(x606, x603, uint64(p521Uint1(x626)))
-	var x629 uint64
-	var x630 uint64
-	x629, x630 = bits.Add64(x604, x601, uint64(p521Uint1(x628)))
-	var x631 uint64
-	var x632 uint64
-	x631, x632 = bits.Add64(x602, x599, uint64(p521Uint1(x630)))
-	x633 := (uint64(p521Uint1(x632)) + x600)
-	var x635 uint64
-	_, x635 = bits.Add64(x579, x615, uint64(0x0))
-	var x636 uint64
-	var x637 uint64
-	x636, x637 = bits.Add64(x581, x617, uint64(p521Uint1(x635)))
-	var x638 uint64
-	var x639 uint64
-	x638, x639 = bits.Add64(x583, x619, uint64(p521Uint1(x637)))
-	var x640 uint64
-	var x641 uint64
-	x640, x641 = bits.Add64(x585, x621, uint64(p521Uint1(x639)))
-	var x642 uint64
-	var x643 uint64
-	x642, x643 = bits.Add64(x587, x623, uint64(p521Uint1(x641)))
-	var x644 uint64
-	var x645 uint64
-	x644, x645 = bits.Add64(x589, x625, uint64(p521Uint1(x643)))
-	var x646 uint64
-	var x647 uint64
-	x646, x647 = bits.Add64(x591, x627, uint64(p521Uint1(x645)))
-	var x648 uint64
-	var x649 uint64
-	x648, x649 = bits.Add64(x593, x629, uint64(p521Uint1(x647)))
-	var x650 uint64
-	var x651 uint64
-	x650, x651 = bits.Add64(x595, x631, uint64(p521Uint1(x649)))
-	var x652 uint64
-	var x653 uint64
-	x652, x653 = bits.Add64(x597, x633, uint64(p521Uint1(x651)))
-	x654 := (uint64(p521Uint1(x653)) + uint64(p521Uint1(x598)))
-	var x655 uint64
-	var x656 uint64
-	x656, x655 = bits.Mul64(x6, arg1[8])
-	var x657 uint64
-	var x658 uint64
-	x658, x657 = bits.Mul64(x6, arg1[7])
-	var x659 uint64
-	var x660 uint64
-	x660, x659 = bits.Mul64(x6, arg1[6])
-	var x661 uint64
-	var x662 uint64
-	x662, x661 = bits.Mul64(x6, arg1[5])
-	var x663 uint64
-	var x664 uint64
-	x664, x663 = bits.Mul64(x6, arg1[4])
-	var x665 uint64
-	var x666 uint64
-	x666, x665 = bits.Mul64(x6, arg1[3])
-	var x667 uint64
-	var x668 uint64
-	x668, x667 = bits.Mul64(x6, arg1[2])
-	var x669 uint64
-	var x670 uint64
-	x670, x669 = bits.Mul64(x6, arg1[1])
-	var x671 uint64
-	var x672 uint64
-	x672, x671 = bits.Mul64(x6, arg1[0])
-	var x673 uint64
-	var x674 uint64
-	x673, x674 = bits.Add64(x672, x669, uint64(0x0))
-	var x675 uint64
-	var x676 uint64
-	x675, x676 = bits.Add64(x670, x667, uint64(p521Uint1(x674)))
-	var x677 uint64
-	var x678 uint64
-	x677, x678 = bits.Add64(x668, x665, uint64(p521Uint1(x676)))
-	var x679 uint64
-	var x680 uint64
-	x679, x680 = bits.Add64(x666, x663, uint64(p521Uint1(x678)))
-	var x681 uint64
-	var x682 uint64
-	x681, x682 = bits.Add64(x664, x661, uint64(p521Uint1(x680)))
-	var x683 uint64
-	var x684 uint64
-	x683, x684 = bits.Add64(x662, x659, uint64(p521Uint1(x682)))
-	var x685 uint64
-	var x686 uint64
-	x685, x686 = bits.Add64(x660, x657, uint64(p521Uint1(x684)))
-	var x687 uint64
-	var x688 uint64
-	x687, x688 = bits.Add64(x658, x655, uint64(p521Uint1(x686)))
-	x689 := (uint64(p521Uint1(x688)) + x656)
-	var x690 uint64
-	var x691 uint64
-	x690, x691 = bits.Add64(x636, x671, uint64(0x0))
-	var x692 uint64
-	var x693 uint64
-	x692, x693 = bits.Add64(x638, x673, uint64(p521Uint1(x691)))
-	var x694 uint64
-	var x695 uint64
-	x694, x695 = bits.Add64(x640, x675, uint64(p521Uint1(x693)))
-	var x696 uint64
-	var x697 uint64
-	x696, x697 = bits.Add64(x642, x677, uint64(p521Uint1(x695)))
-	var x698 uint64
-	var x699 uint64
-	x698, x699 = bits.Add64(x644, x679, uint64(p521Uint1(x697)))
-	var x700 uint64
-	var x701 uint64
-	x700, x701 = bits.Add64(x646, x681, uint64(p521Uint1(x699)))
-	var x702 uint64
-	var x703 uint64
-	x702, x703 = bits.Add64(x648, x683, uint64(p521Uint1(x701)))
-	var x704 uint64
-	var x705 uint64
-	x704, x705 = bits.Add64(x650, x685, uint64(p521Uint1(x703)))
-	var x706 uint64
-	var x707 uint64
-	x706, x707 = bits.Add64(x652, x687, uint64(p521Uint1(x705)))
-	var x708 uint64
-	var x709 uint64
-	x708, x709 = bits.Add64(x654, x689, uint64(p521Uint1(x707)))
-	var x710 uint64
-	var x711 uint64
-	x711, x710 = bits.Mul64(x690, 0x1ff)
-	var x712 uint64
-	var x713 uint64
-	x713, x712 = bits.Mul64(x690, 0xffffffffffffffff)
-	var x714 uint64
-	var x715 uint64
-	x715, x714 = bits.Mul64(x690, 0xffffffffffffffff)
-	var x716 uint64
-	var x717 uint64
-	x717, x716 = bits.Mul64(x690, 0xffffffffffffffff)
-	var x718 uint64
-	var x719 uint64
-	x719, x718 = bits.Mul64(x690, 0xffffffffffffffff)
-	var x720 uint64
-	var x721 uint64
-	x721, x720 = bits.Mul64(x690, 0xffffffffffffffff)
-	var x722 uint64
-	var x723 uint64
-	x723, x722 = bits.Mul64(x690, 0xffffffffffffffff)
-	var x724 uint64
-	var x725 uint64
-	x725, x724 = bits.Mul64(x690, 0xffffffffffffffff)
-	var x726 uint64
-	var x727 uint64
-	x727, x726 = bits.Mul64(x690, 0xffffffffffffffff)
-	var x728 uint64
-	var x729 uint64
-	x728, x729 = bits.Add64(x727, x724, uint64(0x0))
-	var x730 uint64
-	var x731 uint64
-	x730, x731 = bits.Add64(x725, x722, uint64(p521Uint1(x729)))
-	var x732 uint64
-	var x733 uint64
-	x732, x733 = bits.Add64(x723, x720, uint64(p521Uint1(x731)))
-	var x734 uint64
-	var x735 uint64
-	x734, x735 = bits.Add64(x721, x718, uint64(p521Uint1(x733)))
-	var x736 uint64
-	var x737 uint64
-	x736, x737 = bits.Add64(x719, x716, uint64(p521Uint1(x735)))
-	var x738 uint64
-	var x739 uint64
-	x738, x739 = bits.Add64(x717, x714, uint64(p521Uint1(x737)))
-	var x740 uint64
-	var x741 uint64
-	x740, x741 = bits.Add64(x715, x712, uint64(p521Uint1(x739)))
-	var x742 uint64
-	var x743 uint64
-	x742, x743 = bits.Add64(x713, x710, uint64(p521Uint1(x741)))
-	x744 := (uint64(p521Uint1(x743)) + x711)
-	var x746 uint64
-	_, x746 = bits.Add64(x690, x726, uint64(0x0))
-	var x747 uint64
-	var x748 uint64
-	x747, x748 = bits.Add64(x692, x728, uint64(p521Uint1(x746)))
-	var x749 uint64
-	var x750 uint64
-	x749, x750 = bits.Add64(x694, x730, uint64(p521Uint1(x748)))
-	var x751 uint64
-	var x752 uint64
-	x751, x752 = bits.Add64(x696, x732, uint64(p521Uint1(x750)))
-	var x753 uint64
-	var x754 uint64
-	x753, x754 = bits.Add64(x698, x734, uint64(p521Uint1(x752)))
-	var x755 uint64
-	var x756 uint64
-	x755, x756 = bits.Add64(x700, x736, uint64(p521Uint1(x754)))
-	var x757 uint64
-	var x758 uint64
-	x757, x758 = bits.Add64(x702, x738, uint64(p521Uint1(x756)))
-	var x759 uint64
-	var x760 uint64
-	x759, x760 = bits.Add64(x704, x740, uint64(p521Uint1(x758)))
-	var x761 uint64
-	var x762 uint64
-	x761, x762 = bits.Add64(x706, x742, uint64(p521Uint1(x760)))
-	var x763 uint64
-	var x764 uint64
-	x763, x764 = bits.Add64(x708, x744, uint64(p521Uint1(x762)))
-	x765 := (uint64(p521Uint1(x764)) + uint64(p521Uint1(x709)))
-	var x766 uint64
-	var x767 uint64
-	x767, x766 = bits.Mul64(x7, arg1[8])
-	var x768 uint64
-	var x769 uint64
-	x769, x768 = bits.Mul64(x7, arg1[7])
-	var x770 uint64
-	var x771 uint64
-	x771, x770 = bits.Mul64(x7, arg1[6])
-	var x772 uint64
-	var x773 uint64
-	x773, x772 = bits.Mul64(x7, arg1[5])
-	var x774 uint64
-	var x775 uint64
-	x775, x774 = bits.Mul64(x7, arg1[4])
-	var x776 uint64
-	var x777 uint64
-	x777, x776 = bits.Mul64(x7, arg1[3])
-	var x778 uint64
-	var x779 uint64
-	x779, x778 = bits.Mul64(x7, arg1[2])
-	var x780 uint64
-	var x781 uint64
-	x781, x780 = bits.Mul64(x7, arg1[1])
-	var x782 uint64
-	var x783 uint64
-	x783, x782 = bits.Mul64(x7, arg1[0])
-	var x784 uint64
-	var x785 uint64
-	x784, x785 = bits.Add64(x783, x780, uint64(0x0))
-	var x786 uint64
-	var x787 uint64
-	x786, x787 = bits.Add64(x781, x778, uint64(p521Uint1(x785)))
-	var x788 uint64
-	var x789 uint64
-	x788, x789 = bits.Add64(x779, x776, uint64(p521Uint1(x787)))
-	var x790 uint64
-	var x791 uint64
-	x790, x791 = bits.Add64(x777, x774, uint64(p521Uint1(x789)))
-	var x792 uint64
-	var x793 uint64
-	x792, x793 = bits.Add64(x775, x772, uint64(p521Uint1(x791)))
-	var x794 uint64
-	var x795 uint64
-	x794, x795 = bits.Add64(x773, x770, uint64(p521Uint1(x793)))
-	var x796 uint64
-	var x797 uint64
-	x796, x797 = bits.Add64(x771, x768, uint64(p521Uint1(x795)))
-	var x798 uint64
-	var x799 uint64
-	x798, x799 = bits.Add64(x769, x766, uint64(p521Uint1(x797)))
-	x800 := (uint64(p521Uint1(x799)) + x767)
-	var x801 uint64
-	var x802 uint64
-	x801, x802 = bits.Add64(x747, x782, uint64(0x0))
-	var x803 uint64
-	var x804 uint64
-	x803, x804 = bits.Add64(x749, x784, uint64(p521Uint1(x802)))
-	var x805 uint64
-	var x806 uint64
-	x805, x806 = bits.Add64(x751, x786, uint64(p521Uint1(x804)))
-	var x807 uint64
-	var x808 uint64
-	x807, x808 = bits.Add64(x753, x788, uint64(p521Uint1(x806)))
-	var x809 uint64
-	var x810 uint64
-	x809, x810 = bits.Add64(x755, x790, uint64(p521Uint1(x808)))
-	var x811 uint64
-	var x812 uint64
-	x811, x812 = bits.Add64(x757, x792, uint64(p521Uint1(x810)))
-	var x813 uint64
-	var x814 uint64
-	x813, x814 = bits.Add64(x759, x794, uint64(p521Uint1(x812)))
-	var x815 uint64
-	var x816 uint64
-	x815, x816 = bits.Add64(x761, x796, uint64(p521Uint1(x814)))
-	var x817 uint64
-	var x818 uint64
-	x817, x818 = bits.Add64(x763, x798, uint64(p521Uint1(x816)))
-	var x819 uint64
-	var x820 uint64
-	x819, x820 = bits.Add64(x765, x800, uint64(p521Uint1(x818)))
-	var x821 uint64
-	var x822 uint64
-	x822, x821 = bits.Mul64(x801, 0x1ff)
-	var x823 uint64
-	var x824 uint64
-	x824, x823 = bits.Mul64(x801, 0xffffffffffffffff)
-	var x825 uint64
-	var x826 uint64
-	x826, x825 = bits.Mul64(x801, 0xffffffffffffffff)
-	var x827 uint64
-	var x828 uint64
-	x828, x827 = bits.Mul64(x801, 0xffffffffffffffff)
-	var x829 uint64
-	var x830 uint64
-	x830, x829 = bits.Mul64(x801, 0xffffffffffffffff)
-	var x831 uint64
-	var x832 uint64
-	x832, x831 = bits.Mul64(x801, 0xffffffffffffffff)
-	var x833 uint64
-	var x834 uint64
-	x834, x833 = bits.Mul64(x801, 0xffffffffffffffff)
-	var x835 uint64
-	var x836 uint64
-	x836, x835 = bits.Mul64(x801, 0xffffffffffffffff)
-	var x837 uint64
-	var x838 uint64
-	x838, x837 = bits.Mul64(x801, 0xffffffffffffffff)
-	var x839 uint64
-	var x840 uint64
-	x839, x840 = bits.Add64(x838, x835, uint64(0x0))
-	var x841 uint64
-	var x842 uint64
-	x841, x842 = bits.Add64(x836, x833, uint64(p521Uint1(x840)))
-	var x843 uint64
-	var x844 uint64
-	x843, x844 = bits.Add64(x834, x831, uint64(p521Uint1(x842)))
-	var x845 uint64
-	var x846 uint64
-	x845, x846 = bits.Add64(x832, x829, uint64(p521Uint1(x844)))
-	var x847 uint64
-	var x848 uint64
-	x847, x848 = bits.Add64(x830, x827, uint64(p521Uint1(x846)))
-	var x849 uint64
-	var x850 uint64
-	x849, x850 = bits.Add64(x828, x825, uint64(p521Uint1(x848)))
-	var x851 uint64
-	var x852 uint64
-	x851, x852 = bits.Add64(x826, x823, uint64(p521Uint1(x850)))
-	var x853 uint64
-	var x854 uint64
-	x853, x854 = bits.Add64(x824, x821, uint64(p521Uint1(x852)))
-	x855 := (uint64(p521Uint1(x854)) + x822)
-	var x857 uint64
-	_, x857 = bits.Add64(x801, x837, uint64(0x0))
-	var x858 uint64
-	var x859 uint64
-	x858, x859 = bits.Add64(x803, x839, uint64(p521Uint1(x857)))
-	var x860 uint64
-	var x861 uint64
-	x860, x861 = bits.Add64(x805, x841, uint64(p521Uint1(x859)))
-	var x862 uint64
-	var x863 uint64
-	x862, x863 = bits.Add64(x807, x843, uint64(p521Uint1(x861)))
-	var x864 uint64
-	var x865 uint64
-	x864, x865 = bits.Add64(x809, x845, uint64(p521Uint1(x863)))
-	var x866 uint64
-	var x867 uint64
-	x866, x867 = bits.Add64(x811, x847, uint64(p521Uint1(x865)))
-	var x868 uint64
-	var x869 uint64
-	x868, x869 = bits.Add64(x813, x849, uint64(p521Uint1(x867)))
-	var x870 uint64
-	var x871 uint64
-	x870, x871 = bits.Add64(x815, x851, uint64(p521Uint1(x869)))
-	var x872 uint64
-	var x873 uint64
-	x872, x873 = bits.Add64(x817, x853, uint64(p521Uint1(x871)))
-	var x874 uint64
-	var x875 uint64
-	x874, x875 = bits.Add64(x819, x855, uint64(p521Uint1(x873)))
-	x876 := (uint64(p521Uint1(x875)) + uint64(p521Uint1(x820)))
-	var x877 uint64
-	var x878 uint64
-	x878, x877 = bits.Mul64(x8, arg1[8])
-	var x879 uint64
-	var x880 uint64
-	x880, x879 = bits.Mul64(x8, arg1[7])
-	var x881 uint64
-	var x882 uint64
-	x882, x881 = bits.Mul64(x8, arg1[6])
-	var x883 uint64
-	var x884 uint64
-	x884, x883 = bits.Mul64(x8, arg1[5])
-	var x885 uint64
-	var x886 uint64
-	x886, x885 = bits.Mul64(x8, arg1[4])
-	var x887 uint64
-	var x888 uint64
-	x888, x887 = bits.Mul64(x8, arg1[3])
-	var x889 uint64
-	var x890 uint64
-	x890, x889 = bits.Mul64(x8, arg1[2])
-	var x891 uint64
-	var x892 uint64
-	x892, x891 = bits.Mul64(x8, arg1[1])
-	var x893 uint64
-	var x894 uint64
-	x894, x893 = bits.Mul64(x8, arg1[0])
-	var x895 uint64
-	var x896 uint64
-	x895, x896 = bits.Add64(x894, x891, uint64(0x0))
-	var x897 uint64
-	var x898 uint64
-	x897, x898 = bits.Add64(x892, x889, uint64(p521Uint1(x896)))
-	var x899 uint64
-	var x900 uint64
-	x899, x900 = bits.Add64(x890, x887, uint64(p521Uint1(x898)))
-	var x901 uint64
-	var x902 uint64
-	x901, x902 = bits.Add64(x888, x885, uint64(p521Uint1(x900)))
-	var x903 uint64
-	var x904 uint64
-	x903, x904 = bits.Add64(x886, x883, uint64(p521Uint1(x902)))
-	var x905 uint64
-	var x906 uint64
-	x905, x906 = bits.Add64(x884, x881, uint64(p521Uint1(x904)))
-	var x907 uint64
-	var x908 uint64
-	x907, x908 = bits.Add64(x882, x879, uint64(p521Uint1(x906)))
-	var x909 uint64
-	var x910 uint64
-	x909, x910 = bits.Add64(x880, x877, uint64(p521Uint1(x908)))
-	x911 := (uint64(p521Uint1(x910)) + x878)
-	var x912 uint64
-	var x913 uint64
-	x912, x913 = bits.Add64(x858, x893, uint64(0x0))
-	var x914 uint64
-	var x915 uint64
-	x914, x915 = bits.Add64(x860, x895, uint64(p521Uint1(x913)))
-	var x916 uint64
-	var x917 uint64
-	x916, x917 = bits.Add64(x862, x897, uint64(p521Uint1(x915)))
-	var x918 uint64
-	var x919 uint64
-	x918, x919 = bits.Add64(x864, x899, uint64(p521Uint1(x917)))
-	var x920 uint64
-	var x921 uint64
-	x920, x921 = bits.Add64(x866, x901, uint64(p521Uint1(x919)))
-	var x922 uint64
-	var x923 uint64
-	x922, x923 = bits.Add64(x868, x903, uint64(p521Uint1(x921)))
-	var x924 uint64
-	var x925 uint64
-	x924, x925 = bits.Add64(x870, x905, uint64(p521Uint1(x923)))
-	var x926 uint64
-	var x927 uint64
-	x926, x927 = bits.Add64(x872, x907, uint64(p521Uint1(x925)))
-	var x928 uint64
-	var x929 uint64
-	x928, x929 = bits.Add64(x874, x909, uint64(p521Uint1(x927)))
-	var x930 uint64
-	var x931 uint64
-	x930, x931 = bits.Add64(x876, x911, uint64(p521Uint1(x929)))
-	var x932 uint64
-	var x933 uint64
-	x933, x932 = bits.Mul64(x912, 0x1ff)
-	var x934 uint64
-	var x935 uint64
-	x935, x934 = bits.Mul64(x912, 0xffffffffffffffff)
-	var x936 uint64
-	var x937 uint64
-	x937, x936 = bits.Mul64(x912, 0xffffffffffffffff)
-	var x938 uint64
-	var x939 uint64
-	x939, x938 = bits.Mul64(x912, 0xffffffffffffffff)
-	var x940 uint64
-	var x941 uint64
-	x941, x940 = bits.Mul64(x912, 0xffffffffffffffff)
-	var x942 uint64
-	var x943 uint64
-	x943, x942 = bits.Mul64(x912, 0xffffffffffffffff)
-	var x944 uint64
-	var x945 uint64
-	x945, x944 = bits.Mul64(x912, 0xffffffffffffffff)
-	var x946 uint64
-	var x947 uint64
-	x947, x946 = bits.Mul64(x912, 0xffffffffffffffff)
-	var x948 uint64
-	var x949 uint64
-	x949, x948 = bits.Mul64(x912, 0xffffffffffffffff)
-	var x950 uint64
-	var x951 uint64
-	x950, x951 = bits.Add64(x949, x946, uint64(0x0))
-	var x952 uint64
-	var x953 uint64
-	x952, x953 = bits.Add64(x947, x944, uint64(p521Uint1(x951)))
-	var x954 uint64
-	var x955 uint64
-	x954, x955 = bits.Add64(x945, x942, uint64(p521Uint1(x953)))
-	var x956 uint64
-	var x957 uint64
-	x956, x957 = bits.Add64(x943, x940, uint64(p521Uint1(x955)))
-	var x958 uint64
-	var x959 uint64
-	x958, x959 = bits.Add64(x941, x938, uint64(p521Uint1(x957)))
-	var x960 uint64
-	var x961 uint64
-	x960, x961 = bits.Add64(x939, x936, uint64(p521Uint1(x959)))
-	var x962 uint64
-	var x963 uint64
-	x962, x963 = bits.Add64(x937, x934, uint64(p521Uint1(x961)))
-	var x964 uint64
-	var x965 uint64
-	x964, x965 = bits.Add64(x935, x932, uint64(p521Uint1(x963)))
-	x966 := (uint64(p521Uint1(x965)) + x933)
-	var x968 uint64
-	_, x968 = bits.Add64(x912, x948, uint64(0x0))
-	var x969 uint64
-	var x970 uint64
-	x969, x970 = bits.Add64(x914, x950, uint64(p521Uint1(x968)))
-	var x971 uint64
-	var x972 uint64
-	x971, x972 = bits.Add64(x916, x952, uint64(p521Uint1(x970)))
-	var x973 uint64
-	var x974 uint64
-	x973, x974 = bits.Add64(x918, x954, uint64(p521Uint1(x972)))
-	var x975 uint64
-	var x976 uint64
-	x975, x976 = bits.Add64(x920, x956, uint64(p521Uint1(x974)))
-	var x977 uint64
-	var x978 uint64
-	x977, x978 = bits.Add64(x922, x958, uint64(p521Uint1(x976)))
-	var x979 uint64
-	var x980 uint64
-	x979, x980 = bits.Add64(x924, x960, uint64(p521Uint1(x978)))
-	var x981 uint64
-	var x982 uint64
-	x981, x982 = bits.Add64(x926, x962, uint64(p521Uint1(x980)))
-	var x983 uint64
-	var x984 uint64
-	x983, x984 = bits.Add64(x928, x964, uint64(p521Uint1(x982)))
-	var x985 uint64
-	var x986 uint64
-	x985, x986 = bits.Add64(x930, x966, uint64(p521Uint1(x984)))
-	x987 := (uint64(p521Uint1(x986)) + uint64(p521Uint1(x931)))
-	var x988 uint64
-	var x989 uint64
-	x988, x989 = bits.Sub64(x969, 0xffffffffffffffff, uint64(0x0))
-	var x990 uint64
-	var x991 uint64
-	x990, x991 = bits.Sub64(x971, 0xffffffffffffffff, uint64(p521Uint1(x989)))
-	var x992 uint64
-	var x993 uint64
-	x992, x993 = bits.Sub64(x973, 0xffffffffffffffff, uint64(p521Uint1(x991)))
-	var x994 uint64
-	var x995 uint64
-	x994, x995 = bits.Sub64(x975, 0xffffffffffffffff, uint64(p521Uint1(x993)))
-	var x996 uint64
-	var x997 uint64
-	x996, x997 = bits.Sub64(x977, 0xffffffffffffffff, uint64(p521Uint1(x995)))
-	var x998 uint64
-	var x999 uint64
-	x998, x999 = bits.Sub64(x979, 0xffffffffffffffff, uint64(p521Uint1(x997)))
-	var x1000 uint64
-	var x1001 uint64
-	x1000, x1001 = bits.Sub64(x981, 0xffffffffffffffff, uint64(p521Uint1(x999)))
-	var x1002 uint64
-	var x1003 uint64
-	x1002, x1003 = bits.Sub64(x983, 0xffffffffffffffff, uint64(p521Uint1(x1001)))
-	var x1004 uint64
-	var x1005 uint64
-	x1004, x1005 = bits.Sub64(x985, 0x1ff, uint64(p521Uint1(x1003)))
-	var x1007 uint64
-	_, x1007 = bits.Sub64(x987, uint64(0x0), uint64(p521Uint1(x1005)))
-	var x1008 uint64
-	p521CmovznzU64(&x1008, p521Uint1(x1007), x988, x969)
-	var x1009 uint64
-	p521CmovznzU64(&x1009, p521Uint1(x1007), x990, x971)
-	var x1010 uint64
-	p521CmovznzU64(&x1010, p521Uint1(x1007), x992, x973)
-	var x1011 uint64
-	p521CmovznzU64(&x1011, p521Uint1(x1007), x994, x975)
-	var x1012 uint64
-	p521CmovznzU64(&x1012, p521Uint1(x1007), x996, x977)
-	var x1013 uint64
-	p521CmovznzU64(&x1013, p521Uint1(x1007), x998, x979)
-	var x1014 uint64
-	p521CmovznzU64(&x1014, p521Uint1(x1007), x1000, x981)
-	var x1015 uint64
-	p521CmovznzU64(&x1015, p521Uint1(x1007), x1002, x983)
-	var x1016 uint64
-	p521CmovznzU64(&x1016, p521Uint1(x1007), x1004, x985)
-	out1[0] = x1008
-	out1[1] = x1009
-	out1[2] = x1010
-	out1[3] = x1011
-	out1[4] = x1012
-	out1[5] = x1013
-	out1[6] = x1014
-	out1[7] = x1015
-	out1[8] = x1016
-}
-
-// p521Add adds two field elements in the Montgomery domain.
-//
-// Preconditions:
-//   0 ≤ eval arg1 < m
-//   0 ≤ eval arg2 < m
-// Postconditions:
-//   eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) + eval (from_montgomery arg2)) mod m
-//   0 ≤ eval out1 < m
-//
-func p521Add(out1 *p521MontgomeryDomainFieldElement, arg1 *p521MontgomeryDomainFieldElement, arg2 *p521MontgomeryDomainFieldElement) {
-	var x1 uint64
-	var x2 uint64
-	x1, x2 = bits.Add64(arg1[0], arg2[0], uint64(0x0))
-	var x3 uint64
-	var x4 uint64
-	x3, x4 = bits.Add64(arg1[1], arg2[1], uint64(p521Uint1(x2)))
-	var x5 uint64
-	var x6 uint64
-	x5, x6 = bits.Add64(arg1[2], arg2[2], uint64(p521Uint1(x4)))
-	var x7 uint64
-	var x8 uint64
-	x7, x8 = bits.Add64(arg1[3], arg2[3], uint64(p521Uint1(x6)))
-	var x9 uint64
-	var x10 uint64
-	x9, x10 = bits.Add64(arg1[4], arg2[4], uint64(p521Uint1(x8)))
-	var x11 uint64
-	var x12 uint64
-	x11, x12 = bits.Add64(arg1[5], arg2[5], uint64(p521Uint1(x10)))
-	var x13 uint64
-	var x14 uint64
-	x13, x14 = bits.Add64(arg1[6], arg2[6], uint64(p521Uint1(x12)))
-	var x15 uint64
-	var x16 uint64
-	x15, x16 = bits.Add64(arg1[7], arg2[7], uint64(p521Uint1(x14)))
-	var x17 uint64
-	var x18 uint64
-	x17, x18 = bits.Add64(arg1[8], arg2[8], uint64(p521Uint1(x16)))
-	var x19 uint64
-	var x20 uint64
-	x19, x20 = bits.Sub64(x1, 0xffffffffffffffff, uint64(0x0))
-	var x21 uint64
-	var x22 uint64
-	x21, x22 = bits.Sub64(x3, 0xffffffffffffffff, uint64(p521Uint1(x20)))
-	var x23 uint64
-	var x24 uint64
-	x23, x24 = bits.Sub64(x5, 0xffffffffffffffff, uint64(p521Uint1(x22)))
-	var x25 uint64
-	var x26 uint64
-	x25, x26 = bits.Sub64(x7, 0xffffffffffffffff, uint64(p521Uint1(x24)))
-	var x27 uint64
-	var x28 uint64
-	x27, x28 = bits.Sub64(x9, 0xffffffffffffffff, uint64(p521Uint1(x26)))
-	var x29 uint64
-	var x30 uint64
-	x29, x30 = bits.Sub64(x11, 0xffffffffffffffff, uint64(p521Uint1(x28)))
-	var x31 uint64
-	var x32 uint64
-	x31, x32 = bits.Sub64(x13, 0xffffffffffffffff, uint64(p521Uint1(x30)))
-	var x33 uint64
-	var x34 uint64
-	x33, x34 = bits.Sub64(x15, 0xffffffffffffffff, uint64(p521Uint1(x32)))
-	var x35 uint64
-	var x36 uint64
-	x35, x36 = bits.Sub64(x17, 0x1ff, uint64(p521Uint1(x34)))
-	var x38 uint64
-	_, x38 = bits.Sub64(uint64(p521Uint1(x18)), uint64(0x0), uint64(p521Uint1(x36)))
-	var x39 uint64
-	p521CmovznzU64(&x39, p521Uint1(x38), x19, x1)
-	var x40 uint64
-	p521CmovznzU64(&x40, p521Uint1(x38), x21, x3)
-	var x41 uint64
-	p521CmovznzU64(&x41, p521Uint1(x38), x23, x5)
-	var x42 uint64
-	p521CmovznzU64(&x42, p521Uint1(x38), x25, x7)
-	var x43 uint64
-	p521CmovznzU64(&x43, p521Uint1(x38), x27, x9)
-	var x44 uint64
-	p521CmovznzU64(&x44, p521Uint1(x38), x29, x11)
-	var x45 uint64
-	p521CmovznzU64(&x45, p521Uint1(x38), x31, x13)
-	var x46 uint64
-	p521CmovznzU64(&x46, p521Uint1(x38), x33, x15)
-	var x47 uint64
-	p521CmovznzU64(&x47, p521Uint1(x38), x35, x17)
-	out1[0] = x39
-	out1[1] = x40
-	out1[2] = x41
-	out1[3] = x42
-	out1[4] = x43
-	out1[5] = x44
-	out1[6] = x45
-	out1[7] = x46
-	out1[8] = x47
-}
-
-// p521Sub subtracts two field elements in the Montgomery domain.
-//
-// Preconditions:
-//   0 ≤ eval arg1 < m
-//   0 ≤ eval arg2 < m
-// Postconditions:
-//   eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) - eval (from_montgomery arg2)) mod m
-//   0 ≤ eval out1 < m
-//
-func p521Sub(out1 *p521MontgomeryDomainFieldElement, arg1 *p521MontgomeryDomainFieldElement, arg2 *p521MontgomeryDomainFieldElement) {
-	var x1 uint64
-	var x2 uint64
-	x1, x2 = bits.Sub64(arg1[0], arg2[0], uint64(0x0))
-	var x3 uint64
-	var x4 uint64
-	x3, x4 = bits.Sub64(arg1[1], arg2[1], uint64(p521Uint1(x2)))
-	var x5 uint64
-	var x6 uint64
-	x5, x6 = bits.Sub64(arg1[2], arg2[2], uint64(p521Uint1(x4)))
-	var x7 uint64
-	var x8 uint64
-	x7, x8 = bits.Sub64(arg1[3], arg2[3], uint64(p521Uint1(x6)))
-	var x9 uint64
-	var x10 uint64
-	x9, x10 = bits.Sub64(arg1[4], arg2[4], uint64(p521Uint1(x8)))
-	var x11 uint64
-	var x12 uint64
-	x11, x12 = bits.Sub64(arg1[5], arg2[5], uint64(p521Uint1(x10)))
-	var x13 uint64
-	var x14 uint64
-	x13, x14 = bits.Sub64(arg1[6], arg2[6], uint64(p521Uint1(x12)))
-	var x15 uint64
-	var x16 uint64
-	x15, x16 = bits.Sub64(arg1[7], arg2[7], uint64(p521Uint1(x14)))
-	var x17 uint64
-	var x18 uint64
-	x17, x18 = bits.Sub64(arg1[8], arg2[8], uint64(p521Uint1(x16)))
-	var x19 uint64
-	p521CmovznzU64(&x19, p521Uint1(x18), uint64(0x0), 0xffffffffffffffff)
-	var x20 uint64
-	var x21 uint64
-	x20, x21 = bits.Add64(x1, x19, uint64(0x0))
-	var x22 uint64
-	var x23 uint64
-	x22, x23 = bits.Add64(x3, x19, uint64(p521Uint1(x21)))
-	var x24 uint64
-	var x25 uint64
-	x24, x25 = bits.Add64(x5, x19, uint64(p521Uint1(x23)))
-	var x26 uint64
-	var x27 uint64
-	x26, x27 = bits.Add64(x7, x19, uint64(p521Uint1(x25)))
-	var x28 uint64
-	var x29 uint64
-	x28, x29 = bits.Add64(x9, x19, uint64(p521Uint1(x27)))
-	var x30 uint64
-	var x31 uint64
-	x30, x31 = bits.Add64(x11, x19, uint64(p521Uint1(x29)))
-	var x32 uint64
-	var x33 uint64
-	x32, x33 = bits.Add64(x13, x19, uint64(p521Uint1(x31)))
-	var x34 uint64
-	var x35 uint64
-	x34, x35 = bits.Add64(x15, x19, uint64(p521Uint1(x33)))
-	var x36 uint64
-	x36, _ = bits.Add64(x17, (x19 & 0x1ff), uint64(p521Uint1(x35)))
-	out1[0] = x20
-	out1[1] = x22
-	out1[2] = x24
-	out1[3] = x26
-	out1[4] = x28
-	out1[5] = x30
-	out1[6] = x32
-	out1[7] = x34
-	out1[8] = x36
-}
-
-// p521SetOne returns the field element one in the Montgomery domain.
-//
-// Postconditions:
-//   eval (from_montgomery out1) mod m = 1 mod m
-//   0 ≤ eval out1 < m
-//
-func p521SetOne(out1 *p521MontgomeryDomainFieldElement) {
-	out1[0] = 0x80000000000000
-	out1[1] = uint64(0x0)
-	out1[2] = uint64(0x0)
-	out1[3] = uint64(0x0)
-	out1[4] = uint64(0x0)
-	out1[5] = uint64(0x0)
-	out1[6] = uint64(0x0)
-	out1[7] = uint64(0x0)
-	out1[8] = uint64(0x0)
-}
-
-// p521FromMontgomery translates a field element out of the Montgomery domain.
-//
-// Preconditions:
-//   0 ≤ eval arg1 < m
-// Postconditions:
-//   eval out1 mod m = (eval arg1 * ((2^64)⁻¹ mod m)^9) mod m
-//   0 ≤ eval out1 < m
-//
-func p521FromMontgomery(out1 *p521NonMontgomeryDomainFieldElement, arg1 *p521MontgomeryDomainFieldElement) {
-	x1 := arg1[0]
-	var x2 uint64
-	var x3 uint64
-	x3, x2 = bits.Mul64(x1, 0x1ff)
-	var x4 uint64
-	var x5 uint64
-	x5, x4 = bits.Mul64(x1, 0xffffffffffffffff)
-	var x6 uint64
-	var x7 uint64
-	x7, x6 = bits.Mul64(x1, 0xffffffffffffffff)
-	var x8 uint64
-	var x9 uint64
-	x9, x8 = bits.Mul64(x1, 0xffffffffffffffff)
-	var x10 uint64
-	var x11 uint64
-	x11, x10 = bits.Mul64(x1, 0xffffffffffffffff)
-	var x12 uint64
-	var x13 uint64
-	x13, x12 = bits.Mul64(x1, 0xffffffffffffffff)
-	var x14 uint64
-	var x15 uint64
-	x15, x14 = bits.Mul64(x1, 0xffffffffffffffff)
-	var x16 uint64
-	var x17 uint64
-	x17, x16 = bits.Mul64(x1, 0xffffffffffffffff)
-	var x18 uint64
-	var x19 uint64
-	x19, x18 = bits.Mul64(x1, 0xffffffffffffffff)
-	var x20 uint64
-	var x21 uint64
-	x20, x21 = bits.Add64(x19, x16, uint64(0x0))
-	var x22 uint64
-	var x23 uint64
-	x22, x23 = bits.Add64(x17, x14, uint64(p521Uint1(x21)))
-	var x24 uint64
-	var x25 uint64
-	x24, x25 = bits.Add64(x15, x12, uint64(p521Uint1(x23)))
-	var x26 uint64
-	var x27 uint64
-	x26, x27 = bits.Add64(x13, x10, uint64(p521Uint1(x25)))
-	var x28 uint64
-	var x29 uint64
-	x28, x29 = bits.Add64(x11, x8, uint64(p521Uint1(x27)))
-	var x30 uint64
-	var x31 uint64
-	x30, x31 = bits.Add64(x9, x6, uint64(p521Uint1(x29)))
-	var x32 uint64
-	var x33 uint64
-	x32, x33 = bits.Add64(x7, x4, uint64(p521Uint1(x31)))
-	var x34 uint64
-	var x35 uint64
-	x34, x35 = bits.Add64(x5, x2, uint64(p521Uint1(x33)))
-	var x37 uint64
-	_, x37 = bits.Add64(x1, x18, uint64(0x0))
-	var x38 uint64
-	var x39 uint64
-	x38, x39 = bits.Add64(uint64(0x0), x20, uint64(p521Uint1(x37)))
-	var x40 uint64
-	var x41 uint64
-	x40, x41 = bits.Add64(uint64(0x0), x22, uint64(p521Uint1(x39)))
-	var x42 uint64
-	var x43 uint64
-	x42, x43 = bits.Add64(uint64(0x0), x24, uint64(p521Uint1(x41)))
-	var x44 uint64
-	var x45 uint64
-	x44, x45 = bits.Add64(uint64(0x0), x26, uint64(p521Uint1(x43)))
-	var x46 uint64
-	var x47 uint64
-	x46, x47 = bits.Add64(uint64(0x0), x28, uint64(p521Uint1(x45)))
-	var x48 uint64
-	var x49 uint64
-	x48, x49 = bits.Add64(uint64(0x0), x30, uint64(p521Uint1(x47)))
-	var x50 uint64
-	var x51 uint64
-	x50, x51 = bits.Add64(uint64(0x0), x32, uint64(p521Uint1(x49)))
-	var x52 uint64
-	var x53 uint64
-	x52, x53 = bits.Add64(uint64(0x0), x34, uint64(p521Uint1(x51)))
-	var x54 uint64
-	var x55 uint64
-	x54, x55 = bits.Add64(x38, arg1[1], uint64(0x0))
-	var x56 uint64
-	var x57 uint64
-	x56, x57 = bits.Add64(x40, uint64(0x0), uint64(p521Uint1(x55)))
-	var x58 uint64
-	var x59 uint64
-	x58, x59 = bits.Add64(x42, uint64(0x0), uint64(p521Uint1(x57)))
-	var x60 uint64
-	var x61 uint64
-	x60, x61 = bits.Add64(x44, uint64(0x0), uint64(p521Uint1(x59)))
-	var x62 uint64
-	var x63 uint64
-	x62, x63 = bits.Add64(x46, uint64(0x0), uint64(p521Uint1(x61)))
-	var x64 uint64
-	var x65 uint64
-	x64, x65 = bits.Add64(x48, uint64(0x0), uint64(p521Uint1(x63)))
-	var x66 uint64
-	var x67 uint64
-	x66, x67 = bits.Add64(x50, uint64(0x0), uint64(p521Uint1(x65)))
-	var x68 uint64
-	var x69 uint64
-	x68, x69 = bits.Add64(x52, uint64(0x0), uint64(p521Uint1(x67)))
-	var x70 uint64
-	var x71 uint64
-	x71, x70 = bits.Mul64(x54, 0x1ff)
-	var x72 uint64
-	var x73 uint64
-	x73, x72 = bits.Mul64(x54, 0xffffffffffffffff)
-	var x74 uint64
-	var x75 uint64
-	x75, x74 = bits.Mul64(x54, 0xffffffffffffffff)
-	var x76 uint64
-	var x77 uint64
-	x77, x76 = bits.Mul64(x54, 0xffffffffffffffff)
-	var x78 uint64
-	var x79 uint64
-	x79, x78 = bits.Mul64(x54, 0xffffffffffffffff)
-	var x80 uint64
-	var x81 uint64
-	x81, x80 = bits.Mul64(x54, 0xffffffffffffffff)
-	var x82 uint64
-	var x83 uint64
-	x83, x82 = bits.Mul64(x54, 0xffffffffffffffff)
-	var x84 uint64
-	var x85 uint64
-	x85, x84 = bits.Mul64(x54, 0xffffffffffffffff)
-	var x86 uint64
-	var x87 uint64
-	x87, x86 = bits.Mul64(x54, 0xffffffffffffffff)
-	var x88 uint64
-	var x89 uint64
-	x88, x89 = bits.Add64(x87, x84, uint64(0x0))
-	var x90 uint64
-	var x91 uint64
-	x90, x91 = bits.Add64(x85, x82, uint64(p521Uint1(x89)))
-	var x92 uint64
-	var x93 uint64
-	x92, x93 = bits.Add64(x83, x80, uint64(p521Uint1(x91)))
-	var x94 uint64
-	var x95 uint64
-	x94, x95 = bits.Add64(x81, x78, uint64(p521Uint1(x93)))
-	var x96 uint64
-	var x97 uint64
-	x96, x97 = bits.Add64(x79, x76, uint64(p521Uint1(x95)))
-	var x98 uint64
-	var x99 uint64
-	x98, x99 = bits.Add64(x77, x74, uint64(p521Uint1(x97)))
-	var x100 uint64
-	var x101 uint64
-	x100, x101 = bits.Add64(x75, x72, uint64(p521Uint1(x99)))
-	var x102 uint64
-	var x103 uint64
-	x102, x103 = bits.Add64(x73, x70, uint64(p521Uint1(x101)))
-	var x105 uint64
-	_, x105 = bits.Add64(x54, x86, uint64(0x0))
-	var x106 uint64
-	var x107 uint64
-	x106, x107 = bits.Add64(x56, x88, uint64(p521Uint1(x105)))
-	var x108 uint64
-	var x109 uint64
-	x108, x109 = bits.Add64(x58, x90, uint64(p521Uint1(x107)))
-	var x110 uint64
-	var x111 uint64
-	x110, x111 = bits.Add64(x60, x92, uint64(p521Uint1(x109)))
-	var x112 uint64
-	var x113 uint64
-	x112, x113 = bits.Add64(x62, x94, uint64(p521Uint1(x111)))
-	var x114 uint64
-	var x115 uint64
-	x114, x115 = bits.Add64(x64, x96, uint64(p521Uint1(x113)))
-	var x116 uint64
-	var x117 uint64
-	x116, x117 = bits.Add64(x66, x98, uint64(p521Uint1(x115)))
-	var x118 uint64
-	var x119 uint64
-	x118, x119 = bits.Add64(x68, x100, uint64(p521Uint1(x117)))
-	var x120 uint64
-	var x121 uint64
-	x120, x121 = bits.Add64((uint64(p521Uint1(x69)) + (uint64(p521Uint1(x53)) + (uint64(p521Uint1(x35)) + x3))), x102, uint64(p521Uint1(x119)))
-	var x122 uint64
-	var x123 uint64
-	x122, x123 = bits.Add64(x106, arg1[2], uint64(0x0))
-	var x124 uint64
-	var x125 uint64
-	x124, x125 = bits.Add64(x108, uint64(0x0), uint64(p521Uint1(x123)))
-	var x126 uint64
-	var x127 uint64
-	x126, x127 = bits.Add64(x110, uint64(0x0), uint64(p521Uint1(x125)))
-	var x128 uint64
-	var x129 uint64
-	x128, x129 = bits.Add64(x112, uint64(0x0), uint64(p521Uint1(x127)))
-	var x130 uint64
-	var x131 uint64
-	x130, x131 = bits.Add64(x114, uint64(0x0), uint64(p521Uint1(x129)))
-	var x132 uint64
-	var x133 uint64
-	x132, x133 = bits.Add64(x116, uint64(0x0), uint64(p521Uint1(x131)))
-	var x134 uint64
-	var x135 uint64
-	x134, x135 = bits.Add64(x118, uint64(0x0), uint64(p521Uint1(x133)))
-	var x136 uint64
-	var x137 uint64
-	x136, x137 = bits.Add64(x120, uint64(0x0), uint64(p521Uint1(x135)))
-	var x138 uint64
-	var x139 uint64
-	x139, x138 = bits.Mul64(x122, 0x1ff)
-	var x140 uint64
-	var x141 uint64
-	x141, x140 = bits.Mul64(x122, 0xffffffffffffffff)
-	var x142 uint64
-	var x143 uint64
-	x143, x142 = bits.Mul64(x122, 0xffffffffffffffff)
-	var x144 uint64
-	var x145 uint64
-	x145, x144 = bits.Mul64(x122, 0xffffffffffffffff)
-	var x146 uint64
-	var x147 uint64
-	x147, x146 = bits.Mul64(x122, 0xffffffffffffffff)
-	var x148 uint64
-	var x149 uint64
-	x149, x148 = bits.Mul64(x122, 0xffffffffffffffff)
-	var x150 uint64
-	var x151 uint64
-	x151, x150 = bits.Mul64(x122, 0xffffffffffffffff)
-	var x152 uint64
-	var x153 uint64
-	x153, x152 = bits.Mul64(x122, 0xffffffffffffffff)
-	var x154 uint64
-	var x155 uint64
-	x155, x154 = bits.Mul64(x122, 0xffffffffffffffff)
-	var x156 uint64
-	var x157 uint64
-	x156, x157 = bits.Add64(x155, x152, uint64(0x0))
-	var x158 uint64
-	var x159 uint64
-	x158, x159 = bits.Add64(x153, x150, uint64(p521Uint1(x157)))
-	var x160 uint64
-	var x161 uint64
-	x160, x161 = bits.Add64(x151, x148, uint64(p521Uint1(x159)))
-	var x162 uint64
-	var x163 uint64
-	x162, x163 = bits.Add64(x149, x146, uint64(p521Uint1(x161)))
-	var x164 uint64
-	var x165 uint64
-	x164, x165 = bits.Add64(x147, x144, uint64(p521Uint1(x163)))
-	var x166 uint64
-	var x167 uint64
-	x166, x167 = bits.Add64(x145, x142, uint64(p521Uint1(x165)))
-	var x168 uint64
-	var x169 uint64
-	x168, x169 = bits.Add64(x143, x140, uint64(p521Uint1(x167)))
-	var x170 uint64
-	var x171 uint64
-	x170, x171 = bits.Add64(x141, x138, uint64(p521Uint1(x169)))
-	var x173 uint64
-	_, x173 = bits.Add64(x122, x154, uint64(0x0))
-	var x174 uint64
-	var x175 uint64
-	x174, x175 = bits.Add64(x124, x156, uint64(p521Uint1(x173)))
-	var x176 uint64
-	var x177 uint64
-	x176, x177 = bits.Add64(x126, x158, uint64(p521Uint1(x175)))
-	var x178 uint64
-	var x179 uint64
-	x178, x179 = bits.Add64(x128, x160, uint64(p521Uint1(x177)))
-	var x180 uint64
-	var x181 uint64
-	x180, x181 = bits.Add64(x130, x162, uint64(p521Uint1(x179)))
-	var x182 uint64
-	var x183 uint64
-	x182, x183 = bits.Add64(x132, x164, uint64(p521Uint1(x181)))
-	var x184 uint64
-	var x185 uint64
-	x184, x185 = bits.Add64(x134, x166, uint64(p521Uint1(x183)))
-	var x186 uint64
-	var x187 uint64
-	x186, x187 = bits.Add64(x136, x168, uint64(p521Uint1(x185)))
-	var x188 uint64
-	var x189 uint64
-	x188, x189 = bits.Add64((uint64(p521Uint1(x137)) + (uint64(p521Uint1(x121)) + (uint64(p521Uint1(x103)) + x71))), x170, uint64(p521Uint1(x187)))
-	var x190 uint64
-	var x191 uint64
-	x190, x191 = bits.Add64(x174, arg1[3], uint64(0x0))
-	var x192 uint64
-	var x193 uint64
-	x192, x193 = bits.Add64(x176, uint64(0x0), uint64(p521Uint1(x191)))
-	var x194 uint64
-	var x195 uint64
-	x194, x195 = bits.Add64(x178, uint64(0x0), uint64(p521Uint1(x193)))
-	var x196 uint64
-	var x197 uint64
-	x196, x197 = bits.Add64(x180, uint64(0x0), uint64(p521Uint1(x195)))
-	var x198 uint64
-	var x199 uint64
-	x198, x199 = bits.Add64(x182, uint64(0x0), uint64(p521Uint1(x197)))
-	var x200 uint64
-	var x201 uint64
-	x200, x201 = bits.Add64(x184, uint64(0x0), uint64(p521Uint1(x199)))
-	var x202 uint64
-	var x203 uint64
-	x202, x203 = bits.Add64(x186, uint64(0x0), uint64(p521Uint1(x201)))
-	var x204 uint64
-	var x205 uint64
-	x204, x205 = bits.Add64(x188, uint64(0x0), uint64(p521Uint1(x203)))
-	var x206 uint64
-	var x207 uint64
-	x207, x206 = bits.Mul64(x190, 0x1ff)
-	var x208 uint64
-	var x209 uint64
-	x209, x208 = bits.Mul64(x190, 0xffffffffffffffff)
-	var x210 uint64
-	var x211 uint64
-	x211, x210 = bits.Mul64(x190, 0xffffffffffffffff)
-	var x212 uint64
-	var x213 uint64
-	x213, x212 = bits.Mul64(x190, 0xffffffffffffffff)
-	var x214 uint64
-	var x215 uint64
-	x215, x214 = bits.Mul64(x190, 0xffffffffffffffff)
-	var x216 uint64
-	var x217 uint64
-	x217, x216 = bits.Mul64(x190, 0xffffffffffffffff)
-	var x218 uint64
-	var x219 uint64
-	x219, x218 = bits.Mul64(x190, 0xffffffffffffffff)
-	var x220 uint64
-	var x221 uint64
-	x221, x220 = bits.Mul64(x190, 0xffffffffffffffff)
-	var x222 uint64
-	var x223 uint64
-	x223, x222 = bits.Mul64(x190, 0xffffffffffffffff)
-	var x224 uint64
-	var x225 uint64
-	x224, x225 = bits.Add64(x223, x220, uint64(0x0))
-	var x226 uint64
-	var x227 uint64
-	x226, x227 = bits.Add64(x221, x218, uint64(p521Uint1(x225)))
-	var x228 uint64
-	var x229 uint64
-	x228, x229 = bits.Add64(x219, x216, uint64(p521Uint1(x227)))
-	var x230 uint64
-	var x231 uint64
-	x230, x231 = bits.Add64(x217, x214, uint64(p521Uint1(x229)))
-	var x232 uint64
-	var x233 uint64
-	x232, x233 = bits.Add64(x215, x212, uint64(p521Uint1(x231)))
-	var x234 uint64
-	var x235 uint64
-	x234, x235 = bits.Add64(x213, x210, uint64(p521Uint1(x233)))
-	var x236 uint64
-	var x237 uint64
-	x236, x237 = bits.Add64(x211, x208, uint64(p521Uint1(x235)))
-	var x238 uint64
-	var x239 uint64
-	x238, x239 = bits.Add64(x209, x206, uint64(p521Uint1(x237)))
-	var x241 uint64
-	_, x241 = bits.Add64(x190, x222, uint64(0x0))
-	var x242 uint64
-	var x243 uint64
-	x242, x243 = bits.Add64(x192, x224, uint64(p521Uint1(x241)))
-	var x244 uint64
-	var x245 uint64
-	x244, x245 = bits.Add64(x194, x226, uint64(p521Uint1(x243)))
-	var x246 uint64
-	var x247 uint64
-	x246, x247 = bits.Add64(x196, x228, uint64(p521Uint1(x245)))
-	var x248 uint64
-	var x249 uint64
-	x248, x249 = bits.Add64(x198, x230, uint64(p521Uint1(x247)))
-	var x250 uint64
-	var x251 uint64
-	x250, x251 = bits.Add64(x200, x232, uint64(p521Uint1(x249)))
-	var x252 uint64
-	var x253 uint64
-	x252, x253 = bits.Add64(x202, x234, uint64(p521Uint1(x251)))
-	var x254 uint64
-	var x255 uint64
-	x254, x255 = bits.Add64(x204, x236, uint64(p521Uint1(x253)))
-	var x256 uint64
-	var x257 uint64
-	x256, x257 = bits.Add64((uint64(p521Uint1(x205)) + (uint64(p521Uint1(x189)) + (uint64(p521Uint1(x171)) + x139))), x238, uint64(p521Uint1(x255)))
-	var x258 uint64
-	var x259 uint64
-	x258, x259 = bits.Add64(x242, arg1[4], uint64(0x0))
-	var x260 uint64
-	var x261 uint64
-	x260, x261 = bits.Add64(x244, uint64(0x0), uint64(p521Uint1(x259)))
-	var x262 uint64
-	var x263 uint64
-	x262, x263 = bits.Add64(x246, uint64(0x0), uint64(p521Uint1(x261)))
-	var x264 uint64
-	var x265 uint64
-	x264, x265 = bits.Add64(x248, uint64(0x0), uint64(p521Uint1(x263)))
-	var x266 uint64
-	var x267 uint64
-	x266, x267 = bits.Add64(x250, uint64(0x0), uint64(p521Uint1(x265)))
-	var x268 uint64
-	var x269 uint64
-	x268, x269 = bits.Add64(x252, uint64(0x0), uint64(p521Uint1(x267)))
-	var x270 uint64
-	var x271 uint64
-	x270, x271 = bits.Add64(x254, uint64(0x0), uint64(p521Uint1(x269)))
-	var x272 uint64
-	var x273 uint64
-	x272, x273 = bits.Add64(x256, uint64(0x0), uint64(p521Uint1(x271)))
-	var x274 uint64
-	var x275 uint64
-	x275, x274 = bits.Mul64(x258, 0x1ff)
-	var x276 uint64
-	var x277 uint64
-	x277, x276 = bits.Mul64(x258, 0xffffffffffffffff)
-	var x278 uint64
-	var x279 uint64
-	x279, x278 = bits.Mul64(x258, 0xffffffffffffffff)
-	var x280 uint64
-	var x281 uint64
-	x281, x280 = bits.Mul64(x258, 0xffffffffffffffff)
-	var x282 uint64
-	var x283 uint64
-	x283, x282 = bits.Mul64(x258, 0xffffffffffffffff)
-	var x284 uint64
-	var x285 uint64
-	x285, x284 = bits.Mul64(x258, 0xffffffffffffffff)
-	var x286 uint64
-	var x287 uint64
-	x287, x286 = bits.Mul64(x258, 0xffffffffffffffff)
-	var x288 uint64
-	var x289 uint64
-	x289, x288 = bits.Mul64(x258, 0xffffffffffffffff)
-	var x290 uint64
-	var x291 uint64
-	x291, x290 = bits.Mul64(x258, 0xffffffffffffffff)
-	var x292 uint64
-	var x293 uint64
-	x292, x293 = bits.Add64(x291, x288, uint64(0x0))
-	var x294 uint64
-	var x295 uint64
-	x294, x295 = bits.Add64(x289, x286, uint64(p521Uint1(x293)))
-	var x296 uint64
-	var x297 uint64
-	x296, x297 = bits.Add64(x287, x284, uint64(p521Uint1(x295)))
-	var x298 uint64
-	var x299 uint64
-	x298, x299 = bits.Add64(x285, x282, uint64(p521Uint1(x297)))
-	var x300 uint64
-	var x301 uint64
-	x300, x301 = bits.Add64(x283, x280, uint64(p521Uint1(x299)))
-	var x302 uint64
-	var x303 uint64
-	x302, x303 = bits.Add64(x281, x278, uint64(p521Uint1(x301)))
-	var x304 uint64
-	var x305 uint64
-	x304, x305 = bits.Add64(x279, x276, uint64(p521Uint1(x303)))
-	var x306 uint64
-	var x307 uint64
-	x306, x307 = bits.Add64(x277, x274, uint64(p521Uint1(x305)))
-	var x309 uint64
-	_, x309 = bits.Add64(x258, x290, uint64(0x0))
-	var x310 uint64
-	var x311 uint64
-	x310, x311 = bits.Add64(x260, x292, uint64(p521Uint1(x309)))
-	var x312 uint64
-	var x313 uint64
-	x312, x313 = bits.Add64(x262, x294, uint64(p521Uint1(x311)))
-	var x314 uint64
-	var x315 uint64
-	x314, x315 = bits.Add64(x264, x296, uint64(p521Uint1(x313)))
-	var x316 uint64
-	var x317 uint64
-	x316, x317 = bits.Add64(x266, x298, uint64(p521Uint1(x315)))
-	var x318 uint64
-	var x319 uint64
-	x318, x319 = bits.Add64(x268, x300, uint64(p521Uint1(x317)))
-	var x320 uint64
-	var x321 uint64
-	x320, x321 = bits.Add64(x270, x302, uint64(p521Uint1(x319)))
-	var x322 uint64
-	var x323 uint64
-	x322, x323 = bits.Add64(x272, x304, uint64(p521Uint1(x321)))
-	var x324 uint64
-	var x325 uint64
-	x324, x325 = bits.Add64((uint64(p521Uint1(x273)) + (uint64(p521Uint1(x257)) + (uint64(p521Uint1(x239)) + x207))), x306, uint64(p521Uint1(x323)))
-	var x326 uint64
-	var x327 uint64
-	x326, x327 = bits.Add64(x310, arg1[5], uint64(0x0))
-	var x328 uint64
-	var x329 uint64
-	x328, x329 = bits.Add64(x312, uint64(0x0), uint64(p521Uint1(x327)))
-	var x330 uint64
-	var x331 uint64
-	x330, x331 = bits.Add64(x314, uint64(0x0), uint64(p521Uint1(x329)))
-	var x332 uint64
-	var x333 uint64
-	x332, x333 = bits.Add64(x316, uint64(0x0), uint64(p521Uint1(x331)))
-	var x334 uint64
-	var x335 uint64
-	x334, x335 = bits.Add64(x318, uint64(0x0), uint64(p521Uint1(x333)))
-	var x336 uint64
-	var x337 uint64
-	x336, x337 = bits.Add64(x320, uint64(0x0), uint64(p521Uint1(x335)))
-	var x338 uint64
-	var x339 uint64
-	x338, x339 = bits.Add64(x322, uint64(0x0), uint64(p521Uint1(x337)))
-	var x340 uint64
-	var x341 uint64
-	x340, x341 = bits.Add64(x324, uint64(0x0), uint64(p521Uint1(x339)))
-	var x342 uint64
-	var x343 uint64
-	x343, x342 = bits.Mul64(x326, 0x1ff)
-	var x344 uint64
-	var x345 uint64
-	x345, x344 = bits.Mul64(x326, 0xffffffffffffffff)
-	var x346 uint64
-	var x347 uint64
-	x347, x346 = bits.Mul64(x326, 0xffffffffffffffff)
-	var x348 uint64
-	var x349 uint64
-	x349, x348 = bits.Mul64(x326, 0xffffffffffffffff)
-	var x350 uint64
-	var x351 uint64
-	x351, x350 = bits.Mul64(x326, 0xffffffffffffffff)
-	var x352 uint64
-	var x353 uint64
-	x353, x352 = bits.Mul64(x326, 0xffffffffffffffff)
-	var x354 uint64
-	var x355 uint64
-	x355, x354 = bits.Mul64(x326, 0xffffffffffffffff)
-	var x356 uint64
-	var x357 uint64
-	x357, x356 = bits.Mul64(x326, 0xffffffffffffffff)
-	var x358 uint64
-	var x359 uint64
-	x359, x358 = bits.Mul64(x326, 0xffffffffffffffff)
-	var x360 uint64
-	var x361 uint64
-	x360, x361 = bits.Add64(x359, x356, uint64(0x0))
-	var x362 uint64
-	var x363 uint64
-	x362, x363 = bits.Add64(x357, x354, uint64(p521Uint1(x361)))
-	var x364 uint64
-	var x365 uint64
-	x364, x365 = bits.Add64(x355, x352, uint64(p521Uint1(x363)))
-	var x366 uint64
-	var x367 uint64
-	x366, x367 = bits.Add64(x353, x350, uint64(p521Uint1(x365)))
-	var x368 uint64
-	var x369 uint64
-	x368, x369 = bits.Add64(x351, x348, uint64(p521Uint1(x367)))
-	var x370 uint64
-	var x371 uint64
-	x370, x371 = bits.Add64(x349, x346, uint64(p521Uint1(x369)))
-	var x372 uint64
-	var x373 uint64
-	x372, x373 = bits.Add64(x347, x344, uint64(p521Uint1(x371)))
-	var x374 uint64
-	var x375 uint64
-	x374, x375 = bits.Add64(x345, x342, uint64(p521Uint1(x373)))
-	var x377 uint64
-	_, x377 = bits.Add64(x326, x358, uint64(0x0))
-	var x378 uint64
-	var x379 uint64
-	x378, x379 = bits.Add64(x328, x360, uint64(p521Uint1(x377)))
-	var x380 uint64
-	var x381 uint64
-	x380, x381 = bits.Add64(x330, x362, uint64(p521Uint1(x379)))
-	var x382 uint64
-	var x383 uint64
-	x382, x383 = bits.Add64(x332, x364, uint64(p521Uint1(x381)))
-	var x384 uint64
-	var x385 uint64
-	x384, x385 = bits.Add64(x334, x366, uint64(p521Uint1(x383)))
-	var x386 uint64
-	var x387 uint64
-	x386, x387 = bits.Add64(x336, x368, uint64(p521Uint1(x385)))
-	var x388 uint64
-	var x389 uint64
-	x388, x389 = bits.Add64(x338, x370, uint64(p521Uint1(x387)))
-	var x390 uint64
-	var x391 uint64
-	x390, x391 = bits.Add64(x340, x372, uint64(p521Uint1(x389)))
-	var x392 uint64
-	var x393 uint64
-	x392, x393 = bits.Add64((uint64(p521Uint1(x341)) + (uint64(p521Uint1(x325)) + (uint64(p521Uint1(x307)) + x275))), x374, uint64(p521Uint1(x391)))
-	var x394 uint64
-	var x395 uint64
-	x394, x395 = bits.Add64(x378, arg1[6], uint64(0x0))
-	var x396 uint64
-	var x397 uint64
-	x396, x397 = bits.Add64(x380, uint64(0x0), uint64(p521Uint1(x395)))
-	var x398 uint64
-	var x399 uint64
-	x398, x399 = bits.Add64(x382, uint64(0x0), uint64(p521Uint1(x397)))
-	var x400 uint64
-	var x401 uint64
-	x400, x401 = bits.Add64(x384, uint64(0x0), uint64(p521Uint1(x399)))
-	var x402 uint64
-	var x403 uint64
-	x402, x403 = bits.Add64(x386, uint64(0x0), uint64(p521Uint1(x401)))
-	var x404 uint64
-	var x405 uint64
-	x404, x405 = bits.Add64(x388, uint64(0x0), uint64(p521Uint1(x403)))
-	var x406 uint64
-	var x407 uint64
-	x406, x407 = bits.Add64(x390, uint64(0x0), uint64(p521Uint1(x405)))
-	var x408 uint64
-	var x409 uint64
-	x408, x409 = bits.Add64(x392, uint64(0x0), uint64(p521Uint1(x407)))
-	var x410 uint64
-	var x411 uint64
-	x411, x410 = bits.Mul64(x394, 0x1ff)
-	var x412 uint64
-	var x413 uint64
-	x413, x412 = bits.Mul64(x394, 0xffffffffffffffff)
-	var x414 uint64
-	var x415 uint64
-	x415, x414 = bits.Mul64(x394, 0xffffffffffffffff)
-	var x416 uint64
-	var x417 uint64
-	x417, x416 = bits.Mul64(x394, 0xffffffffffffffff)
-	var x418 uint64
-	var x419 uint64
-	x419, x418 = bits.Mul64(x394, 0xffffffffffffffff)
-	var x420 uint64
-	var x421 uint64
-	x421, x420 = bits.Mul64(x394, 0xffffffffffffffff)
-	var x422 uint64
-	var x423 uint64
-	x423, x422 = bits.Mul64(x394, 0xffffffffffffffff)
-	var x424 uint64
-	var x425 uint64
-	x425, x424 = bits.Mul64(x394, 0xffffffffffffffff)
-	var x426 uint64
-	var x427 uint64
-	x427, x426 = bits.Mul64(x394, 0xffffffffffffffff)
-	var x428 uint64
-	var x429 uint64
-	x428, x429 = bits.Add64(x427, x424, uint64(0x0))
-	var x430 uint64
-	var x431 uint64
-	x430, x431 = bits.Add64(x425, x422, uint64(p521Uint1(x429)))
-	var x432 uint64
-	var x433 uint64
-	x432, x433 = bits.Add64(x423, x420, uint64(p521Uint1(x431)))
-	var x434 uint64
-	var x435 uint64
-	x434, x435 = bits.Add64(x421, x418, uint64(p521Uint1(x433)))
-	var x436 uint64
-	var x437 uint64
-	x436, x437 = bits.Add64(x419, x416, uint64(p521Uint1(x435)))
-	var x438 uint64
-	var x439 uint64
-	x438, x439 = bits.Add64(x417, x414, uint64(p521Uint1(x437)))
-	var x440 uint64
-	var x441 uint64
-	x440, x441 = bits.Add64(x415, x412, uint64(p521Uint1(x439)))
-	var x442 uint64
-	var x443 uint64
-	x442, x443 = bits.Add64(x413, x410, uint64(p521Uint1(x441)))
-	var x445 uint64
-	_, x445 = bits.Add64(x394, x426, uint64(0x0))
-	var x446 uint64
-	var x447 uint64
-	x446, x447 = bits.Add64(x396, x428, uint64(p521Uint1(x445)))
-	var x448 uint64
-	var x449 uint64
-	x448, x449 = bits.Add64(x398, x430, uint64(p521Uint1(x447)))
-	var x450 uint64
-	var x451 uint64
-	x450, x451 = bits.Add64(x400, x432, uint64(p521Uint1(x449)))
-	var x452 uint64
-	var x453 uint64
-	x452, x453 = bits.Add64(x402, x434, uint64(p521Uint1(x451)))
-	var x454 uint64
-	var x455 uint64
-	x454, x455 = bits.Add64(x404, x436, uint64(p521Uint1(x453)))
-	var x456 uint64
-	var x457 uint64
-	x456, x457 = bits.Add64(x406, x438, uint64(p521Uint1(x455)))
-	var x458 uint64
-	var x459 uint64
-	x458, x459 = bits.Add64(x408, x440, uint64(p521Uint1(x457)))
-	var x460 uint64
-	var x461 uint64
-	x460, x461 = bits.Add64((uint64(p521Uint1(x409)) + (uint64(p521Uint1(x393)) + (uint64(p521Uint1(x375)) + x343))), x442, uint64(p521Uint1(x459)))
-	var x462 uint64
-	var x463 uint64
-	x462, x463 = bits.Add64(x446, arg1[7], uint64(0x0))
-	var x464 uint64
-	var x465 uint64
-	x464, x465 = bits.Add64(x448, uint64(0x0), uint64(p521Uint1(x463)))
-	var x466 uint64
-	var x467 uint64
-	x466, x467 = bits.Add64(x450, uint64(0x0), uint64(p521Uint1(x465)))
-	var x468 uint64
-	var x469 uint64
-	x468, x469 = bits.Add64(x452, uint64(0x0), uint64(p521Uint1(x467)))
-	var x470 uint64
-	var x471 uint64
-	x470, x471 = bits.Add64(x454, uint64(0x0), uint64(p521Uint1(x469)))
-	var x472 uint64
-	var x473 uint64
-	x472, x473 = bits.Add64(x456, uint64(0x0), uint64(p521Uint1(x471)))
-	var x474 uint64
-	var x475 uint64
-	x474, x475 = bits.Add64(x458, uint64(0x0), uint64(p521Uint1(x473)))
-	var x476 uint64
-	var x477 uint64
-	x476, x477 = bits.Add64(x460, uint64(0x0), uint64(p521Uint1(x475)))
-	var x478 uint64
-	var x479 uint64
-	x479, x478 = bits.Mul64(x462, 0x1ff)
-	var x480 uint64
-	var x481 uint64
-	x481, x480 = bits.Mul64(x462, 0xffffffffffffffff)
-	var x482 uint64
-	var x483 uint64
-	x483, x482 = bits.Mul64(x462, 0xffffffffffffffff)
-	var x484 uint64
-	var x485 uint64
-	x485, x484 = bits.Mul64(x462, 0xffffffffffffffff)
-	var x486 uint64
-	var x487 uint64
-	x487, x486 = bits.Mul64(x462, 0xffffffffffffffff)
-	var x488 uint64
-	var x489 uint64
-	x489, x488 = bits.Mul64(x462, 0xffffffffffffffff)
-	var x490 uint64
-	var x491 uint64
-	x491, x490 = bits.Mul64(x462, 0xffffffffffffffff)
-	var x492 uint64
-	var x493 uint64
-	x493, x492 = bits.Mul64(x462, 0xffffffffffffffff)
-	var x494 uint64
-	var x495 uint64
-	x495, x494 = bits.Mul64(x462, 0xffffffffffffffff)
-	var x496 uint64
-	var x497 uint64
-	x496, x497 = bits.Add64(x495, x492, uint64(0x0))
-	var x498 uint64
-	var x499 uint64
-	x498, x499 = bits.Add64(x493, x490, uint64(p521Uint1(x497)))
-	var x500 uint64
-	var x501 uint64
-	x500, x501 = bits.Add64(x491, x488, uint64(p521Uint1(x499)))
-	var x502 uint64
-	var x503 uint64
-	x502, x503 = bits.Add64(x489, x486, uint64(p521Uint1(x501)))
-	var x504 uint64
-	var x505 uint64
-	x504, x505 = bits.Add64(x487, x484, uint64(p521Uint1(x503)))
-	var x506 uint64
-	var x507 uint64
-	x506, x507 = bits.Add64(x485, x482, uint64(p521Uint1(x505)))
-	var x508 uint64
-	var x509 uint64
-	x508, x509 = bits.Add64(x483, x480, uint64(p521Uint1(x507)))
-	var x510 uint64
-	var x511 uint64
-	x510, x511 = bits.Add64(x481, x478, uint64(p521Uint1(x509)))
-	var x513 uint64
-	_, x513 = bits.Add64(x462, x494, uint64(0x0))
-	var x514 uint64
-	var x515 uint64
-	x514, x515 = bits.Add64(x464, x496, uint64(p521Uint1(x513)))
-	var x516 uint64
-	var x517 uint64
-	x516, x517 = bits.Add64(x466, x498, uint64(p521Uint1(x515)))
-	var x518 uint64
-	var x519 uint64
-	x518, x519 = bits.Add64(x468, x500, uint64(p521Uint1(x517)))
-	var x520 uint64
-	var x521 uint64
-	x520, x521 = bits.Add64(x470, x502, uint64(p521Uint1(x519)))
-	var x522 uint64
-	var x523 uint64
-	x522, x523 = bits.Add64(x472, x504, uint64(p521Uint1(x521)))
-	var x524 uint64
-	var x525 uint64
-	x524, x525 = bits.Add64(x474, x506, uint64(p521Uint1(x523)))
-	var x526 uint64
-	var x527 uint64
-	x526, x527 = bits.Add64(x476, x508, uint64(p521Uint1(x525)))
-	var x528 uint64
-	var x529 uint64
-	x528, x529 = bits.Add64((uint64(p521Uint1(x477)) + (uint64(p521Uint1(x461)) + (uint64(p521Uint1(x443)) + x411))), x510, uint64(p521Uint1(x527)))
-	var x530 uint64
-	var x531 uint64
-	x530, x531 = bits.Add64(x514, arg1[8], uint64(0x0))
-	var x532 uint64
-	var x533 uint64
-	x532, x533 = bits.Add64(x516, uint64(0x0), uint64(p521Uint1(x531)))
-	var x534 uint64
-	var x535 uint64
-	x534, x535 = bits.Add64(x518, uint64(0x0), uint64(p521Uint1(x533)))
-	var x536 uint64
-	var x537 uint64
-	x536, x537 = bits.Add64(x520, uint64(0x0), uint64(p521Uint1(x535)))
-	var x538 uint64
-	var x539 uint64
-	x538, x539 = bits.Add64(x522, uint64(0x0), uint64(p521Uint1(x537)))
-	var x540 uint64
-	var x541 uint64
-	x540, x541 = bits.Add64(x524, uint64(0x0), uint64(p521Uint1(x539)))
-	var x542 uint64
-	var x543 uint64
-	x542, x543 = bits.Add64(x526, uint64(0x0), uint64(p521Uint1(x541)))
-	var x544 uint64
-	var x545 uint64
-	x544, x545 = bits.Add64(x528, uint64(0x0), uint64(p521Uint1(x543)))
-	var x546 uint64
-	var x547 uint64
-	x547, x546 = bits.Mul64(x530, 0x1ff)
-	var x548 uint64
-	var x549 uint64
-	x549, x548 = bits.Mul64(x530, 0xffffffffffffffff)
-	var x550 uint64
-	var x551 uint64
-	x551, x550 = bits.Mul64(x530, 0xffffffffffffffff)
-	var x552 uint64
-	var x553 uint64
-	x553, x552 = bits.Mul64(x530, 0xffffffffffffffff)
-	var x554 uint64
-	var x555 uint64
-	x555, x554 = bits.Mul64(x530, 0xffffffffffffffff)
-	var x556 uint64
-	var x557 uint64
-	x557, x556 = bits.Mul64(x530, 0xffffffffffffffff)
-	var x558 uint64
-	var x559 uint64
-	x559, x558 = bits.Mul64(x530, 0xffffffffffffffff)
-	var x560 uint64
-	var x561 uint64
-	x561, x560 = bits.Mul64(x530, 0xffffffffffffffff)
-	var x562 uint64
-	var x563 uint64
-	x563, x562 = bits.Mul64(x530, 0xffffffffffffffff)
-	var x564 uint64
-	var x565 uint64
-	x564, x565 = bits.Add64(x563, x560, uint64(0x0))
-	var x566 uint64
-	var x567 uint64
-	x566, x567 = bits.Add64(x561, x558, uint64(p521Uint1(x565)))
-	var x568 uint64
-	var x569 uint64
-	x568, x569 = bits.Add64(x559, x556, uint64(p521Uint1(x567)))
-	var x570 uint64
-	var x571 uint64
-	x570, x571 = bits.Add64(x557, x554, uint64(p521Uint1(x569)))
-	var x572 uint64
-	var x573 uint64
-	x572, x573 = bits.Add64(x555, x552, uint64(p521Uint1(x571)))
-	var x574 uint64
-	var x575 uint64
-	x574, x575 = bits.Add64(x553, x550, uint64(p521Uint1(x573)))
-	var x576 uint64
-	var x577 uint64
-	x576, x577 = bits.Add64(x551, x548, uint64(p521Uint1(x575)))
-	var x578 uint64
-	var x579 uint64
-	x578, x579 = bits.Add64(x549, x546, uint64(p521Uint1(x577)))
-	var x581 uint64
-	_, x581 = bits.Add64(x530, x562, uint64(0x0))
-	var x582 uint64
-	var x583 uint64
-	x582, x583 = bits.Add64(x532, x564, uint64(p521Uint1(x581)))
-	var x584 uint64
-	var x585 uint64
-	x584, x585 = bits.Add64(x534, x566, uint64(p521Uint1(x583)))
-	var x586 uint64
-	var x587 uint64
-	x586, x587 = bits.Add64(x536, x568, uint64(p521Uint1(x585)))
-	var x588 uint64
-	var x589 uint64
-	x588, x589 = bits.Add64(x538, x570, uint64(p521Uint1(x587)))
-	var x590 uint64
-	var x591 uint64
-	x590, x591 = bits.Add64(x540, x572, uint64(p521Uint1(x589)))
-	var x592 uint64
-	var x593 uint64
-	x592, x593 = bits.Add64(x542, x574, uint64(p521Uint1(x591)))
-	var x594 uint64
-	var x595 uint64
-	x594, x595 = bits.Add64(x544, x576, uint64(p521Uint1(x593)))
-	var x596 uint64
-	var x597 uint64
-	x596, x597 = bits.Add64((uint64(p521Uint1(x545)) + (uint64(p521Uint1(x529)) + (uint64(p521Uint1(x511)) + x479))), x578, uint64(p521Uint1(x595)))
-	x598 := (uint64(p521Uint1(x597)) + (uint64(p521Uint1(x579)) + x547))
-	var x599 uint64
-	var x600 uint64
-	x599, x600 = bits.Sub64(x582, 0xffffffffffffffff, uint64(0x0))
-	var x601 uint64
-	var x602 uint64
-	x601, x602 = bits.Sub64(x584, 0xffffffffffffffff, uint64(p521Uint1(x600)))
-	var x603 uint64
-	var x604 uint64
-	x603, x604 = bits.Sub64(x586, 0xffffffffffffffff, uint64(p521Uint1(x602)))
-	var x605 uint64
-	var x606 uint64
-	x605, x606 = bits.Sub64(x588, 0xffffffffffffffff, uint64(p521Uint1(x604)))
-	var x607 uint64
-	var x608 uint64
-	x607, x608 = bits.Sub64(x590, 0xffffffffffffffff, uint64(p521Uint1(x606)))
-	var x609 uint64
-	var x610 uint64
-	x609, x610 = bits.Sub64(x592, 0xffffffffffffffff, uint64(p521Uint1(x608)))
-	var x611 uint64
-	var x612 uint64
-	x611, x612 = bits.Sub64(x594, 0xffffffffffffffff, uint64(p521Uint1(x610)))
-	var x613 uint64
-	var x614 uint64
-	x613, x614 = bits.Sub64(x596, 0xffffffffffffffff, uint64(p521Uint1(x612)))
-	var x615 uint64
-	var x616 uint64
-	x615, x616 = bits.Sub64(x598, 0x1ff, uint64(p521Uint1(x614)))
-	var x618 uint64
-	_, x618 = bits.Sub64(uint64(0x0), uint64(0x0), uint64(p521Uint1(x616)))
-	var x619 uint64
-	p521CmovznzU64(&x619, p521Uint1(x618), x599, x582)
-	var x620 uint64
-	p521CmovznzU64(&x620, p521Uint1(x618), x601, x584)
-	var x621 uint64
-	p521CmovznzU64(&x621, p521Uint1(x618), x603, x586)
-	var x622 uint64
-	p521CmovznzU64(&x622, p521Uint1(x618), x605, x588)
-	var x623 uint64
-	p521CmovznzU64(&x623, p521Uint1(x618), x607, x590)
-	var x624 uint64
-	p521CmovznzU64(&x624, p521Uint1(x618), x609, x592)
-	var x625 uint64
-	p521CmovznzU64(&x625, p521Uint1(x618), x611, x594)
-	var x626 uint64
-	p521CmovznzU64(&x626, p521Uint1(x618), x613, x596)
-	var x627 uint64
-	p521CmovznzU64(&x627, p521Uint1(x618), x615, x598)
-	out1[0] = x619
-	out1[1] = x620
-	out1[2] = x621
-	out1[3] = x622
-	out1[4] = x623
-	out1[5] = x624
-	out1[6] = x625
-	out1[7] = x626
-	out1[8] = x627
-}
-
-// p521ToMontgomery translates a field element into the Montgomery domain.
-//
-// Preconditions:
-//   0 ≤ eval arg1 < m
-// Postconditions:
-//   eval (from_montgomery out1) mod m = eval arg1 mod m
-//   0 ≤ eval out1 < m
-//
-func p521ToMontgomery(out1 *p521MontgomeryDomainFieldElement, arg1 *p521NonMontgomeryDomainFieldElement) {
-	var x1 uint64
-	var x2 uint64
-	x2, x1 = bits.Mul64(arg1[0], 0x400000000000)
-	var x3 uint64
-	var x4 uint64
-	x4, x3 = bits.Mul64(arg1[1], 0x400000000000)
-	var x5 uint64
-	var x6 uint64
-	x5, x6 = bits.Add64(x2, x3, uint64(0x0))
-	var x7 uint64
-	var x8 uint64
-	x8, x7 = bits.Mul64(x1, 0x1ff)
-	var x9 uint64
-	var x10 uint64
-	x10, x9 = bits.Mul64(x1, 0xffffffffffffffff)
-	var x11 uint64
-	var x12 uint64
-	x12, x11 = bits.Mul64(x1, 0xffffffffffffffff)
-	var x13 uint64
-	var x14 uint64
-	x14, x13 = bits.Mul64(x1, 0xffffffffffffffff)
-	var x15 uint64
-	var x16 uint64
-	x16, x15 = bits.Mul64(x1, 0xffffffffffffffff)
-	var x17 uint64
-	var x18 uint64
-	x18, x17 = bits.Mul64(x1, 0xffffffffffffffff)
-	var x19 uint64
-	var x20 uint64
-	x20, x19 = bits.Mul64(x1, 0xffffffffffffffff)
-	var x21 uint64
-	var x22 uint64
-	x22, x21 = bits.Mul64(x1, 0xffffffffffffffff)
-	var x23 uint64
-	var x24 uint64
-	x24, x23 = bits.Mul64(x1, 0xffffffffffffffff)
-	var x25 uint64
-	var x26 uint64
-	x25, x26 = bits.Add64(x24, x21, uint64(0x0))
-	var x27 uint64
-	var x28 uint64
-	x27, x28 = bits.Add64(x22, x19, uint64(p521Uint1(x26)))
-	var x29 uint64
-	var x30 uint64
-	x29, x30 = bits.Add64(x20, x17, uint64(p521Uint1(x28)))
-	var x31 uint64
-	var x32 uint64
-	x31, x32 = bits.Add64(x18, x15, uint64(p521Uint1(x30)))
-	var x33 uint64
-	var x34 uint64
-	x33, x34 = bits.Add64(x16, x13, uint64(p521Uint1(x32)))
-	var x35 uint64
-	var x36 uint64
-	x35, x36 = bits.Add64(x14, x11, uint64(p521Uint1(x34)))
-	var x37 uint64
-	var x38 uint64
-	x37, x38 = bits.Add64(x12, x9, uint64(p521Uint1(x36)))
-	var x39 uint64
-	var x40 uint64
-	x39, x40 = bits.Add64(x10, x7, uint64(p521Uint1(x38)))
-	var x42 uint64
-	_, x42 = bits.Add64(x1, x23, uint64(0x0))
-	var x43 uint64
-	var x44 uint64
-	x43, x44 = bits.Add64(x5, x25, uint64(p521Uint1(x42)))
-	var x45 uint64
-	var x46 uint64
-	x45, x46 = bits.Add64((uint64(p521Uint1(x6)) + x4), x27, uint64(p521Uint1(x44)))
-	var x47 uint64
-	var x48 uint64
-	x47, x48 = bits.Add64(uint64(0x0), x29, uint64(p521Uint1(x46)))
-	var x49 uint64
-	var x50 uint64
-	x49, x50 = bits.Add64(uint64(0x0), x31, uint64(p521Uint1(x48)))
-	var x51 uint64
-	var x52 uint64
-	x51, x52 = bits.Add64(uint64(0x0), x33, uint64(p521Uint1(x50)))
-	var x53 uint64
-	var x54 uint64
-	x53, x54 = bits.Add64(uint64(0x0), x35, uint64(p521Uint1(x52)))
-	var x55 uint64
-	var x56 uint64
-	x55, x56 = bits.Add64(uint64(0x0), x37, uint64(p521Uint1(x54)))
-	var x57 uint64
-	var x58 uint64
-	x57, x58 = bits.Add64(uint64(0x0), x39, uint64(p521Uint1(x56)))
-	var x59 uint64
-	var x60 uint64
-	x60, x59 = bits.Mul64(arg1[2], 0x400000000000)
-	var x61 uint64
-	var x62 uint64
-	x61, x62 = bits.Add64(x45, x59, uint64(0x0))
-	var x63 uint64
-	var x64 uint64
-	x63, x64 = bits.Add64(x47, x60, uint64(p521Uint1(x62)))
-	var x65 uint64
-	var x66 uint64
-	x65, x66 = bits.Add64(x49, uint64(0x0), uint64(p521Uint1(x64)))
-	var x67 uint64
-	var x68 uint64
-	x67, x68 = bits.Add64(x51, uint64(0x0), uint64(p521Uint1(x66)))
-	var x69 uint64
-	var x70 uint64
-	x69, x70 = bits.Add64(x53, uint64(0x0), uint64(p521Uint1(x68)))
-	var x71 uint64
-	var x72 uint64
-	x71, x72 = bits.Add64(x55, uint64(0x0), uint64(p521Uint1(x70)))
-	var x73 uint64
-	var x74 uint64
-	x73, x74 = bits.Add64(x57, uint64(0x0), uint64(p521Uint1(x72)))
-	var x75 uint64
-	var x76 uint64
-	x76, x75 = bits.Mul64(x43, 0x1ff)
-	var x77 uint64
-	var x78 uint64
-	x78, x77 = bits.Mul64(x43, 0xffffffffffffffff)
-	var x79 uint64
-	var x80 uint64
-	x80, x79 = bits.Mul64(x43, 0xffffffffffffffff)
-	var x81 uint64
-	var x82 uint64
-	x82, x81 = bits.Mul64(x43, 0xffffffffffffffff)
-	var x83 uint64
-	var x84 uint64
-	x84, x83 = bits.Mul64(x43, 0xffffffffffffffff)
-	var x85 uint64
-	var x86 uint64
-	x86, x85 = bits.Mul64(x43, 0xffffffffffffffff)
-	var x87 uint64
-	var x88 uint64
-	x88, x87 = bits.Mul64(x43, 0xffffffffffffffff)
-	var x89 uint64
-	var x90 uint64
-	x90, x89 = bits.Mul64(x43, 0xffffffffffffffff)
-	var x91 uint64
-	var x92 uint64
-	x92, x91 = bits.Mul64(x43, 0xffffffffffffffff)
-	var x93 uint64
-	var x94 uint64
-	x93, x94 = bits.Add64(x92, x89, uint64(0x0))
-	var x95 uint64
-	var x96 uint64
-	x95, x96 = bits.Add64(x90, x87, uint64(p521Uint1(x94)))
-	var x97 uint64
-	var x98 uint64
-	x97, x98 = bits.Add64(x88, x85, uint64(p521Uint1(x96)))
-	var x99 uint64
-	var x100 uint64
-	x99, x100 = bits.Add64(x86, x83, uint64(p521Uint1(x98)))
-	var x101 uint64
-	var x102 uint64
-	x101, x102 = bits.Add64(x84, x81, uint64(p521Uint1(x100)))
-	var x103 uint64
-	var x104 uint64
-	x103, x104 = bits.Add64(x82, x79, uint64(p521Uint1(x102)))
-	var x105 uint64
-	var x106 uint64
-	x105, x106 = bits.Add64(x80, x77, uint64(p521Uint1(x104)))
-	var x107 uint64
-	var x108 uint64
-	x107, x108 = bits.Add64(x78, x75, uint64(p521Uint1(x106)))
-	var x110 uint64
-	_, x110 = bits.Add64(x43, x91, uint64(0x0))
-	var x111 uint64
-	var x112 uint64
-	x111, x112 = bits.Add64(x61, x93, uint64(p521Uint1(x110)))
-	var x113 uint64
-	var x114 uint64
-	x113, x114 = bits.Add64(x63, x95, uint64(p521Uint1(x112)))
-	var x115 uint64
-	var x116 uint64
-	x115, x116 = bits.Add64(x65, x97, uint64(p521Uint1(x114)))
-	var x117 uint64
-	var x118 uint64
-	x117, x118 = bits.Add64(x67, x99, uint64(p521Uint1(x116)))
-	var x119 uint64
-	var x120 uint64
-	x119, x120 = bits.Add64(x69, x101, uint64(p521Uint1(x118)))
-	var x121 uint64
-	var x122 uint64
-	x121, x122 = bits.Add64(x71, x103, uint64(p521Uint1(x120)))
-	var x123 uint64
-	var x124 uint64
-	x123, x124 = bits.Add64(x73, x105, uint64(p521Uint1(x122)))
-	var x125 uint64
-	var x126 uint64
-	x125, x126 = bits.Add64((uint64(p521Uint1(x74)) + (uint64(p521Uint1(x58)) + (uint64(p521Uint1(x40)) + x8))), x107, uint64(p521Uint1(x124)))
-	var x127 uint64
-	var x128 uint64
-	x128, x127 = bits.Mul64(arg1[3], 0x400000000000)
-	var x129 uint64
-	var x130 uint64
-	x129, x130 = bits.Add64(x113, x127, uint64(0x0))
-	var x131 uint64
-	var x132 uint64
-	x131, x132 = bits.Add64(x115, x128, uint64(p521Uint1(x130)))
-	var x133 uint64
-	var x134 uint64
-	x133, x134 = bits.Add64(x117, uint64(0x0), uint64(p521Uint1(x132)))
-	var x135 uint64
-	var x136 uint64
-	x135, x136 = bits.Add64(x119, uint64(0x0), uint64(p521Uint1(x134)))
-	var x137 uint64
-	var x138 uint64
-	x137, x138 = bits.Add64(x121, uint64(0x0), uint64(p521Uint1(x136)))
-	var x139 uint64
-	var x140 uint64
-	x139, x140 = bits.Add64(x123, uint64(0x0), uint64(p521Uint1(x138)))
-	var x141 uint64
-	var x142 uint64
-	x141, x142 = bits.Add64(x125, uint64(0x0), uint64(p521Uint1(x140)))
-	var x143 uint64
-	var x144 uint64
-	x144, x143 = bits.Mul64(x111, 0x1ff)
-	var x145 uint64
-	var x146 uint64
-	x146, x145 = bits.Mul64(x111, 0xffffffffffffffff)
-	var x147 uint64
-	var x148 uint64
-	x148, x147 = bits.Mul64(x111, 0xffffffffffffffff)
-	var x149 uint64
-	var x150 uint64
-	x150, x149 = bits.Mul64(x111, 0xffffffffffffffff)
-	var x151 uint64
-	var x152 uint64
-	x152, x151 = bits.Mul64(x111, 0xffffffffffffffff)
-	var x153 uint64
-	var x154 uint64
-	x154, x153 = bits.Mul64(x111, 0xffffffffffffffff)
-	var x155 uint64
-	var x156 uint64
-	x156, x155 = bits.Mul64(x111, 0xffffffffffffffff)
-	var x157 uint64
-	var x158 uint64
-	x158, x157 = bits.Mul64(x111, 0xffffffffffffffff)
-	var x159 uint64
-	var x160 uint64
-	x160, x159 = bits.Mul64(x111, 0xffffffffffffffff)
-	var x161 uint64
-	var x162 uint64
-	x161, x162 = bits.Add64(x160, x157, uint64(0x0))
-	var x163 uint64
-	var x164 uint64
-	x163, x164 = bits.Add64(x158, x155, uint64(p521Uint1(x162)))
-	var x165 uint64
-	var x166 uint64
-	x165, x166 = bits.Add64(x156, x153, uint64(p521Uint1(x164)))
-	var x167 uint64
-	var x168 uint64
-	x167, x168 = bits.Add64(x154, x151, uint64(p521Uint1(x166)))
-	var x169 uint64
-	var x170 uint64
-	x169, x170 = bits.Add64(x152, x149, uint64(p521Uint1(x168)))
-	var x171 uint64
-	var x172 uint64
-	x171, x172 = bits.Add64(x150, x147, uint64(p521Uint1(x170)))
-	var x173 uint64
-	var x174 uint64
-	x173, x174 = bits.Add64(x148, x145, uint64(p521Uint1(x172)))
-	var x175 uint64
-	var x176 uint64
-	x175, x176 = bits.Add64(x146, x143, uint64(p521Uint1(x174)))
-	var x178 uint64
-	_, x178 = bits.Add64(x111, x159, uint64(0x0))
-	var x179 uint64
-	var x180 uint64
-	x179, x180 = bits.Add64(x129, x161, uint64(p521Uint1(x178)))
-	var x181 uint64
-	var x182 uint64
-	x181, x182 = bits.Add64(x131, x163, uint64(p521Uint1(x180)))
-	var x183 uint64
-	var x184 uint64
-	x183, x184 = bits.Add64(x133, x165, uint64(p521Uint1(x182)))
-	var x185 uint64
-	var x186 uint64
-	x185, x186 = bits.Add64(x135, x167, uint64(p521Uint1(x184)))
-	var x187 uint64
-	var x188 uint64
-	x187, x188 = bits.Add64(x137, x169, uint64(p521Uint1(x186)))
-	var x189 uint64
-	var x190 uint64
-	x189, x190 = bits.Add64(x139, x171, uint64(p521Uint1(x188)))
-	var x191 uint64
-	var x192 uint64
-	x191, x192 = bits.Add64(x141, x173, uint64(p521Uint1(x190)))
-	var x193 uint64
-	var x194 uint64
-	x193, x194 = bits.Add64((uint64(p521Uint1(x142)) + (uint64(p521Uint1(x126)) + (uint64(p521Uint1(x108)) + x76))), x175, uint64(p521Uint1(x192)))
-	var x195 uint64
-	var x196 uint64
-	x196, x195 = bits.Mul64(arg1[4], 0x400000000000)
-	var x197 uint64
-	var x198 uint64
-	x197, x198 = bits.Add64(x181, x195, uint64(0x0))
-	var x199 uint64
-	var x200 uint64
-	x199, x200 = bits.Add64(x183, x196, uint64(p521Uint1(x198)))
-	var x201 uint64
-	var x202 uint64
-	x201, x202 = bits.Add64(x185, uint64(0x0), uint64(p521Uint1(x200)))
-	var x203 uint64
-	var x204 uint64
-	x203, x204 = bits.Add64(x187, uint64(0x0), uint64(p521Uint1(x202)))
-	var x205 uint64
-	var x206 uint64
-	x205, x206 = bits.Add64(x189, uint64(0x0), uint64(p521Uint1(x204)))
-	var x207 uint64
-	var x208 uint64
-	x207, x208 = bits.Add64(x191, uint64(0x0), uint64(p521Uint1(x206)))
-	var x209 uint64
-	var x210 uint64
-	x209, x210 = bits.Add64(x193, uint64(0x0), uint64(p521Uint1(x208)))
-	var x211 uint64
-	var x212 uint64
-	x212, x211 = bits.Mul64(x179, 0x1ff)
-	var x213 uint64
-	var x214 uint64
-	x214, x213 = bits.Mul64(x179, 0xffffffffffffffff)
-	var x215 uint64
-	var x216 uint64
-	x216, x215 = bits.Mul64(x179, 0xffffffffffffffff)
-	var x217 uint64
-	var x218 uint64
-	x218, x217 = bits.Mul64(x179, 0xffffffffffffffff)
-	var x219 uint64
-	var x220 uint64
-	x220, x219 = bits.Mul64(x179, 0xffffffffffffffff)
-	var x221 uint64
-	var x222 uint64
-	x222, x221 = bits.Mul64(x179, 0xffffffffffffffff)
-	var x223 uint64
-	var x224 uint64
-	x224, x223 = bits.Mul64(x179, 0xffffffffffffffff)
-	var x225 uint64
-	var x226 uint64
-	x226, x225 = bits.Mul64(x179, 0xffffffffffffffff)
-	var x227 uint64
-	var x228 uint64
-	x228, x227 = bits.Mul64(x179, 0xffffffffffffffff)
-	var x229 uint64
-	var x230 uint64
-	x229, x230 = bits.Add64(x228, x225, uint64(0x0))
-	var x231 uint64
-	var x232 uint64
-	x231, x232 = bits.Add64(x226, x223, uint64(p521Uint1(x230)))
-	var x233 uint64
-	var x234 uint64
-	x233, x234 = bits.Add64(x224, x221, uint64(p521Uint1(x232)))
-	var x235 uint64
-	var x236 uint64
-	x235, x236 = bits.Add64(x222, x219, uint64(p521Uint1(x234)))
-	var x237 uint64
-	var x238 uint64
-	x237, x238 = bits.Add64(x220, x217, uint64(p521Uint1(x236)))
-	var x239 uint64
-	var x240 uint64
-	x239, x240 = bits.Add64(x218, x215, uint64(p521Uint1(x238)))
-	var x241 uint64
-	var x242 uint64
-	x241, x242 = bits.Add64(x216, x213, uint64(p521Uint1(x240)))
-	var x243 uint64
-	var x244 uint64
-	x243, x244 = bits.Add64(x214, x211, uint64(p521Uint1(x242)))
-	var x246 uint64
-	_, x246 = bits.Add64(x179, x227, uint64(0x0))
-	var x247 uint64
-	var x248 uint64
-	x247, x248 = bits.Add64(x197, x229, uint64(p521Uint1(x246)))
-	var x249 uint64
-	var x250 uint64
-	x249, x250 = bits.Add64(x199, x231, uint64(p521Uint1(x248)))
-	var x251 uint64
-	var x252 uint64
-	x251, x252 = bits.Add64(x201, x233, uint64(p521Uint1(x250)))
-	var x253 uint64
-	var x254 uint64
-	x253, x254 = bits.Add64(x203, x235, uint64(p521Uint1(x252)))
-	var x255 uint64
-	var x256 uint64
-	x255, x256 = bits.Add64(x205, x237, uint64(p521Uint1(x254)))
-	var x257 uint64
-	var x258 uint64
-	x257, x258 = bits.Add64(x207, x239, uint64(p521Uint1(x256)))
-	var x259 uint64
-	var x260 uint64
-	x259, x260 = bits.Add64(x209, x241, uint64(p521Uint1(x258)))
-	var x261 uint64
-	var x262 uint64
-	x261, x262 = bits.Add64((uint64(p521Uint1(x210)) + (uint64(p521Uint1(x194)) + (uint64(p521Uint1(x176)) + x144))), x243, uint64(p521Uint1(x260)))
-	var x263 uint64
-	var x264 uint64
-	x264, x263 = bits.Mul64(arg1[5], 0x400000000000)
-	var x265 uint64
-	var x266 uint64
-	x265, x266 = bits.Add64(x249, x263, uint64(0x0))
-	var x267 uint64
-	var x268 uint64
-	x267, x268 = bits.Add64(x251, x264, uint64(p521Uint1(x266)))
-	var x269 uint64
-	var x270 uint64
-	x269, x270 = bits.Add64(x253, uint64(0x0), uint64(p521Uint1(x268)))
-	var x271 uint64
-	var x272 uint64
-	x271, x272 = bits.Add64(x255, uint64(0x0), uint64(p521Uint1(x270)))
-	var x273 uint64
-	var x274 uint64
-	x273, x274 = bits.Add64(x257, uint64(0x0), uint64(p521Uint1(x272)))
-	var x275 uint64
-	var x276 uint64
-	x275, x276 = bits.Add64(x259, uint64(0x0), uint64(p521Uint1(x274)))
-	var x277 uint64
-	var x278 uint64
-	x277, x278 = bits.Add64(x261, uint64(0x0), uint64(p521Uint1(x276)))
-	var x279 uint64
-	var x280 uint64
-	x280, x279 = bits.Mul64(x247, 0x1ff)
-	var x281 uint64
-	var x282 uint64
-	x282, x281 = bits.Mul64(x247, 0xffffffffffffffff)
-	var x283 uint64
-	var x284 uint64
-	x284, x283 = bits.Mul64(x247, 0xffffffffffffffff)
-	var x285 uint64
-	var x286 uint64
-	x286, x285 = bits.Mul64(x247, 0xffffffffffffffff)
-	var x287 uint64
-	var x288 uint64
-	x288, x287 = bits.Mul64(x247, 0xffffffffffffffff)
-	var x289 uint64
-	var x290 uint64
-	x290, x289 = bits.Mul64(x247, 0xffffffffffffffff)
-	var x291 uint64
-	var x292 uint64
-	x292, x291 = bits.Mul64(x247, 0xffffffffffffffff)
-	var x293 uint64
-	var x294 uint64
-	x294, x293 = bits.Mul64(x247, 0xffffffffffffffff)
-	var x295 uint64
-	var x296 uint64
-	x296, x295 = bits.Mul64(x247, 0xffffffffffffffff)
-	var x297 uint64
-	var x298 uint64
-	x297, x298 = bits.Add64(x296, x293, uint64(0x0))
-	var x299 uint64
-	var x300 uint64
-	x299, x300 = bits.Add64(x294, x291, uint64(p521Uint1(x298)))
-	var x301 uint64
-	var x302 uint64
-	x301, x302 = bits.Add64(x292, x289, uint64(p521Uint1(x300)))
-	var x303 uint64
-	var x304 uint64
-	x303, x304 = bits.Add64(x290, x287, uint64(p521Uint1(x302)))
-	var x305 uint64
-	var x306 uint64
-	x305, x306 = bits.Add64(x288, x285, uint64(p521Uint1(x304)))
-	var x307 uint64
-	var x308 uint64
-	x307, x308 = bits.Add64(x286, x283, uint64(p521Uint1(x306)))
-	var x309 uint64
-	var x310 uint64
-	x309, x310 = bits.Add64(x284, x281, uint64(p521Uint1(x308)))
-	var x311 uint64
-	var x312 uint64
-	x311, x312 = bits.Add64(x282, x279, uint64(p521Uint1(x310)))
-	var x314 uint64
-	_, x314 = bits.Add64(x247, x295, uint64(0x0))
-	var x315 uint64
-	var x316 uint64
-	x315, x316 = bits.Add64(x265, x297, uint64(p521Uint1(x314)))
-	var x317 uint64
-	var x318 uint64
-	x317, x318 = bits.Add64(x267, x299, uint64(p521Uint1(x316)))
-	var x319 uint64
-	var x320 uint64
-	x319, x320 = bits.Add64(x269, x301, uint64(p521Uint1(x318)))
-	var x321 uint64
-	var x322 uint64
-	x321, x322 = bits.Add64(x271, x303, uint64(p521Uint1(x320)))
-	var x323 uint64
-	var x324 uint64
-	x323, x324 = bits.Add64(x273, x305, uint64(p521Uint1(x322)))
-	var x325 uint64
-	var x326 uint64
-	x325, x326 = bits.Add64(x275, x307, uint64(p521Uint1(x324)))
-	var x327 uint64
-	var x328 uint64
-	x327, x328 = bits.Add64(x277, x309, uint64(p521Uint1(x326)))
-	var x329 uint64
-	var x330 uint64
-	x329, x330 = bits.Add64((uint64(p521Uint1(x278)) + (uint64(p521Uint1(x262)) + (uint64(p521Uint1(x244)) + x212))), x311, uint64(p521Uint1(x328)))
-	var x331 uint64
-	var x332 uint64
-	x332, x331 = bits.Mul64(arg1[6], 0x400000000000)
-	var x333 uint64
-	var x334 uint64
-	x333, x334 = bits.Add64(x317, x331, uint64(0x0))
-	var x335 uint64
-	var x336 uint64
-	x335, x336 = bits.Add64(x319, x332, uint64(p521Uint1(x334)))
-	var x337 uint64
-	var x338 uint64
-	x337, x338 = bits.Add64(x321, uint64(0x0), uint64(p521Uint1(x336)))
-	var x339 uint64
-	var x340 uint64
-	x339, x340 = bits.Add64(x323, uint64(0x0), uint64(p521Uint1(x338)))
-	var x341 uint64
-	var x342 uint64
-	x341, x342 = bits.Add64(x325, uint64(0x0), uint64(p521Uint1(x340)))
-	var x343 uint64
-	var x344 uint64
-	x343, x344 = bits.Add64(x327, uint64(0x0), uint64(p521Uint1(x342)))
-	var x345 uint64
-	var x346 uint64
-	x345, x346 = bits.Add64(x329, uint64(0x0), uint64(p521Uint1(x344)))
-	var x347 uint64
-	var x348 uint64
-	x348, x347 = bits.Mul64(x315, 0x1ff)
-	var x349 uint64
-	var x350 uint64
-	x350, x349 = bits.Mul64(x315, 0xffffffffffffffff)
-	var x351 uint64
-	var x352 uint64
-	x352, x351 = bits.Mul64(x315, 0xffffffffffffffff)
-	var x353 uint64
-	var x354 uint64
-	x354, x353 = bits.Mul64(x315, 0xffffffffffffffff)
-	var x355 uint64
-	var x356 uint64
-	x356, x355 = bits.Mul64(x315, 0xffffffffffffffff)
-	var x357 uint64
-	var x358 uint64
-	x358, x357 = bits.Mul64(x315, 0xffffffffffffffff)
-	var x359 uint64
-	var x360 uint64
-	x360, x359 = bits.Mul64(x315, 0xffffffffffffffff)
-	var x361 uint64
-	var x362 uint64
-	x362, x361 = bits.Mul64(x315, 0xffffffffffffffff)
-	var x363 uint64
-	var x364 uint64
-	x364, x363 = bits.Mul64(x315, 0xffffffffffffffff)
-	var x365 uint64
-	var x366 uint64
-	x365, x366 = bits.Add64(x364, x361, uint64(0x0))
-	var x367 uint64
-	var x368 uint64
-	x367, x368 = bits.Add64(x362, x359, uint64(p521Uint1(x366)))
-	var x369 uint64
-	var x370 uint64
-	x369, x370 = bits.Add64(x360, x357, uint64(p521Uint1(x368)))
-	var x371 uint64
-	var x372 uint64
-	x371, x372 = bits.Add64(x358, x355, uint64(p521Uint1(x370)))
-	var x373 uint64
-	var x374 uint64
-	x373, x374 = bits.Add64(x356, x353, uint64(p521Uint1(x372)))
-	var x375 uint64
-	var x376 uint64
-	x375, x376 = bits.Add64(x354, x351, uint64(p521Uint1(x374)))
-	var x377 uint64
-	var x378 uint64
-	x377, x378 = bits.Add64(x352, x349, uint64(p521Uint1(x376)))
-	var x379 uint64
-	var x380 uint64
-	x379, x380 = bits.Add64(x350, x347, uint64(p521Uint1(x378)))
-	var x382 uint64
-	_, x382 = bits.Add64(x315, x363, uint64(0x0))
-	var x383 uint64
-	var x384 uint64
-	x383, x384 = bits.Add64(x333, x365, uint64(p521Uint1(x382)))
-	var x385 uint64
-	var x386 uint64
-	x385, x386 = bits.Add64(x335, x367, uint64(p521Uint1(x384)))
-	var x387 uint64
-	var x388 uint64
-	x387, x388 = bits.Add64(x337, x369, uint64(p521Uint1(x386)))
-	var x389 uint64
-	var x390 uint64
-	x389, x390 = bits.Add64(x339, x371, uint64(p521Uint1(x388)))
-	var x391 uint64
-	var x392 uint64
-	x391, x392 = bits.Add64(x341, x373, uint64(p521Uint1(x390)))
-	var x393 uint64
-	var x394 uint64
-	x393, x394 = bits.Add64(x343, x375, uint64(p521Uint1(x392)))
-	var x395 uint64
-	var x396 uint64
-	x395, x396 = bits.Add64(x345, x377, uint64(p521Uint1(x394)))
-	var x397 uint64
-	var x398 uint64
-	x397, x398 = bits.Add64((uint64(p521Uint1(x346)) + (uint64(p521Uint1(x330)) + (uint64(p521Uint1(x312)) + x280))), x379, uint64(p521Uint1(x396)))
-	var x399 uint64
-	var x400 uint64
-	x400, x399 = bits.Mul64(arg1[7], 0x400000000000)
-	var x401 uint64
-	var x402 uint64
-	x401, x402 = bits.Add64(x385, x399, uint64(0x0))
-	var x403 uint64
-	var x404 uint64
-	x403, x404 = bits.Add64(x387, x400, uint64(p521Uint1(x402)))
-	var x405 uint64
-	var x406 uint64
-	x405, x406 = bits.Add64(x389, uint64(0x0), uint64(p521Uint1(x404)))
-	var x407 uint64
-	var x408 uint64
-	x407, x408 = bits.Add64(x391, uint64(0x0), uint64(p521Uint1(x406)))
-	var x409 uint64
-	var x410 uint64
-	x409, x410 = bits.Add64(x393, uint64(0x0), uint64(p521Uint1(x408)))
-	var x411 uint64
-	var x412 uint64
-	x411, x412 = bits.Add64(x395, uint64(0x0), uint64(p521Uint1(x410)))
-	var x413 uint64
-	var x414 uint64
-	x413, x414 = bits.Add64(x397, uint64(0x0), uint64(p521Uint1(x412)))
-	var x415 uint64
-	var x416 uint64
-	x416, x415 = bits.Mul64(x383, 0x1ff)
-	var x417 uint64
-	var x418 uint64
-	x418, x417 = bits.Mul64(x383, 0xffffffffffffffff)
-	var x419 uint64
-	var x420 uint64
-	x420, x419 = bits.Mul64(x383, 0xffffffffffffffff)
-	var x421 uint64
-	var x422 uint64
-	x422, x421 = bits.Mul64(x383, 0xffffffffffffffff)
-	var x423 uint64
-	var x424 uint64
-	x424, x423 = bits.Mul64(x383, 0xffffffffffffffff)
-	var x425 uint64
-	var x426 uint64
-	x426, x425 = bits.Mul64(x383, 0xffffffffffffffff)
-	var x427 uint64
-	var x428 uint64
-	x428, x427 = bits.Mul64(x383, 0xffffffffffffffff)
-	var x429 uint64
-	var x430 uint64
-	x430, x429 = bits.Mul64(x383, 0xffffffffffffffff)
-	var x431 uint64
-	var x432 uint64
-	x432, x431 = bits.Mul64(x383, 0xffffffffffffffff)
-	var x433 uint64
-	var x434 uint64
-	x433, x434 = bits.Add64(x432, x429, uint64(0x0))
-	var x435 uint64
-	var x436 uint64
-	x435, x436 = bits.Add64(x430, x427, uint64(p521Uint1(x434)))
-	var x437 uint64
-	var x438 uint64
-	x437, x438 = bits.Add64(x428, x425, uint64(p521Uint1(x436)))
-	var x439 uint64
-	var x440 uint64
-	x439, x440 = bits.Add64(x426, x423, uint64(p521Uint1(x438)))
-	var x441 uint64
-	var x442 uint64
-	x441, x442 = bits.Add64(x424, x421, uint64(p521Uint1(x440)))
-	var x443 uint64
-	var x444 uint64
-	x443, x444 = bits.Add64(x422, x419, uint64(p521Uint1(x442)))
-	var x445 uint64
-	var x446 uint64
-	x445, x446 = bits.Add64(x420, x417, uint64(p521Uint1(x444)))
-	var x447 uint64
-	var x448 uint64
-	x447, x448 = bits.Add64(x418, x415, uint64(p521Uint1(x446)))
-	var x450 uint64
-	_, x450 = bits.Add64(x383, x431, uint64(0x0))
-	var x451 uint64
-	var x452 uint64
-	x451, x452 = bits.Add64(x401, x433, uint64(p521Uint1(x450)))
-	var x453 uint64
-	var x454 uint64
-	x453, x454 = bits.Add64(x403, x435, uint64(p521Uint1(x452)))
-	var x455 uint64
-	var x456 uint64
-	x455, x456 = bits.Add64(x405, x437, uint64(p521Uint1(x454)))
-	var x457 uint64
-	var x458 uint64
-	x457, x458 = bits.Add64(x407, x439, uint64(p521Uint1(x456)))
-	var x459 uint64
-	var x460 uint64
-	x459, x460 = bits.Add64(x409, x441, uint64(p521Uint1(x458)))
-	var x461 uint64
-	var x462 uint64
-	x461, x462 = bits.Add64(x411, x443, uint64(p521Uint1(x460)))
-	var x463 uint64
-	var x464 uint64
-	x463, x464 = bits.Add64(x413, x445, uint64(p521Uint1(x462)))
-	var x465 uint64
-	var x466 uint64
-	x465, x466 = bits.Add64((uint64(p521Uint1(x414)) + (uint64(p521Uint1(x398)) + (uint64(p521Uint1(x380)) + x348))), x447, uint64(p521Uint1(x464)))
-	var x467 uint64
-	var x468 uint64
-	x468, x467 = bits.Mul64(arg1[8], 0x400000000000)
-	var x469 uint64
-	var x470 uint64
-	x469, x470 = bits.Add64(x453, x467, uint64(0x0))
-	var x471 uint64
-	var x472 uint64
-	x471, x472 = bits.Add64(x455, x468, uint64(p521Uint1(x470)))
-	var x473 uint64
-	var x474 uint64
-	x473, x474 = bits.Add64(x457, uint64(0x0), uint64(p521Uint1(x472)))
-	var x475 uint64
-	var x476 uint64
-	x475, x476 = bits.Add64(x459, uint64(0x0), uint64(p521Uint1(x474)))
-	var x477 uint64
-	var x478 uint64
-	x477, x478 = bits.Add64(x461, uint64(0x0), uint64(p521Uint1(x476)))
-	var x479 uint64
-	var x480 uint64
-	x479, x480 = bits.Add64(x463, uint64(0x0), uint64(p521Uint1(x478)))
-	var x481 uint64
-	var x482 uint64
-	x481, x482 = bits.Add64(x465, uint64(0x0), uint64(p521Uint1(x480)))
-	var x483 uint64
-	var x484 uint64
-	x484, x483 = bits.Mul64(x451, 0x1ff)
-	var x485 uint64
-	var x486 uint64
-	x486, x485 = bits.Mul64(x451, 0xffffffffffffffff)
-	var x487 uint64
-	var x488 uint64
-	x488, x487 = bits.Mul64(x451, 0xffffffffffffffff)
-	var x489 uint64
-	var x490 uint64
-	x490, x489 = bits.Mul64(x451, 0xffffffffffffffff)
-	var x491 uint64
-	var x492 uint64
-	x492, x491 = bits.Mul64(x451, 0xffffffffffffffff)
-	var x493 uint64
-	var x494 uint64
-	x494, x493 = bits.Mul64(x451, 0xffffffffffffffff)
-	var x495 uint64
-	var x496 uint64
-	x496, x495 = bits.Mul64(x451, 0xffffffffffffffff)
-	var x497 uint64
-	var x498 uint64
-	x498, x497 = bits.Mul64(x451, 0xffffffffffffffff)
-	var x499 uint64
-	var x500 uint64
-	x500, x499 = bits.Mul64(x451, 0xffffffffffffffff)
-	var x501 uint64
-	var x502 uint64
-	x501, x502 = bits.Add64(x500, x497, uint64(0x0))
-	var x503 uint64
-	var x504 uint64
-	x503, x504 = bits.Add64(x498, x495, uint64(p521Uint1(x502)))
-	var x505 uint64
-	var x506 uint64
-	x505, x506 = bits.Add64(x496, x493, uint64(p521Uint1(x504)))
-	var x507 uint64
-	var x508 uint64
-	x507, x508 = bits.Add64(x494, x491, uint64(p521Uint1(x506)))
-	var x509 uint64
-	var x510 uint64
-	x509, x510 = bits.Add64(x492, x489, uint64(p521Uint1(x508)))
-	var x511 uint64
-	var x512 uint64
-	x511, x512 = bits.Add64(x490, x487, uint64(p521Uint1(x510)))
-	var x513 uint64
-	var x514 uint64
-	x513, x514 = bits.Add64(x488, x485, uint64(p521Uint1(x512)))
-	var x515 uint64
-	var x516 uint64
-	x515, x516 = bits.Add64(x486, x483, uint64(p521Uint1(x514)))
-	var x518 uint64
-	_, x518 = bits.Add64(x451, x499, uint64(0x0))
-	var x519 uint64
-	var x520 uint64
-	x519, x520 = bits.Add64(x469, x501, uint64(p521Uint1(x518)))
-	var x521 uint64
-	var x522 uint64
-	x521, x522 = bits.Add64(x471, x503, uint64(p521Uint1(x520)))
-	var x523 uint64
-	var x524 uint64
-	x523, x524 = bits.Add64(x473, x505, uint64(p521Uint1(x522)))
-	var x525 uint64
-	var x526 uint64
-	x525, x526 = bits.Add64(x475, x507, uint64(p521Uint1(x524)))
-	var x527 uint64
-	var x528 uint64
-	x527, x528 = bits.Add64(x477, x509, uint64(p521Uint1(x526)))
-	var x529 uint64
-	var x530 uint64
-	x529, x530 = bits.Add64(x479, x511, uint64(p521Uint1(x528)))
-	var x531 uint64
-	var x532 uint64
-	x531, x532 = bits.Add64(x481, x513, uint64(p521Uint1(x530)))
-	var x533 uint64
-	var x534 uint64
-	x533, x534 = bits.Add64((uint64(p521Uint1(x482)) + (uint64(p521Uint1(x466)) + (uint64(p521Uint1(x448)) + x416))), x515, uint64(p521Uint1(x532)))
-	x535 := (uint64(p521Uint1(x534)) + (uint64(p521Uint1(x516)) + x484))
-	var x536 uint64
-	var x537 uint64
-	x536, x537 = bits.Sub64(x519, 0xffffffffffffffff, uint64(0x0))
-	var x538 uint64
-	var x539 uint64
-	x538, x539 = bits.Sub64(x521, 0xffffffffffffffff, uint64(p521Uint1(x537)))
-	var x540 uint64
-	var x541 uint64
-	x540, x541 = bits.Sub64(x523, 0xffffffffffffffff, uint64(p521Uint1(x539)))
-	var x542 uint64
-	var x543 uint64
-	x542, x543 = bits.Sub64(x525, 0xffffffffffffffff, uint64(p521Uint1(x541)))
-	var x544 uint64
-	var x545 uint64
-	x544, x545 = bits.Sub64(x527, 0xffffffffffffffff, uint64(p521Uint1(x543)))
-	var x546 uint64
-	var x547 uint64
-	x546, x547 = bits.Sub64(x529, 0xffffffffffffffff, uint64(p521Uint1(x545)))
-	var x548 uint64
-	var x549 uint64
-	x548, x549 = bits.Sub64(x531, 0xffffffffffffffff, uint64(p521Uint1(x547)))
-	var x550 uint64
-	var x551 uint64
-	x550, x551 = bits.Sub64(x533, 0xffffffffffffffff, uint64(p521Uint1(x549)))
-	var x552 uint64
-	var x553 uint64
-	x552, x553 = bits.Sub64(x535, 0x1ff, uint64(p521Uint1(x551)))
-	var x555 uint64
-	_, x555 = bits.Sub64(uint64(0x0), uint64(0x0), uint64(p521Uint1(x553)))
-	var x556 uint64
-	p521CmovznzU64(&x556, p521Uint1(x555), x536, x519)
-	var x557 uint64
-	p521CmovznzU64(&x557, p521Uint1(x555), x538, x521)
-	var x558 uint64
-	p521CmovznzU64(&x558, p521Uint1(x555), x540, x523)
-	var x559 uint64
-	p521CmovznzU64(&x559, p521Uint1(x555), x542, x525)
-	var x560 uint64
-	p521CmovznzU64(&x560, p521Uint1(x555), x544, x527)
-	var x561 uint64
-	p521CmovznzU64(&x561, p521Uint1(x555), x546, x529)
-	var x562 uint64
-	p521CmovznzU64(&x562, p521Uint1(x555), x548, x531)
-	var x563 uint64
-	p521CmovznzU64(&x563, p521Uint1(x555), x550, x533)
-	var x564 uint64
-	p521CmovznzU64(&x564, p521Uint1(x555), x552, x535)
-	out1[0] = x556
-	out1[1] = x557
-	out1[2] = x558
-	out1[3] = x559
-	out1[4] = x560
-	out1[5] = x561
-	out1[6] = x562
-	out1[7] = x563
-	out1[8] = x564
-}
-
-// p521Selectznz is a multi-limb conditional select.
-//
-// Postconditions:
-//   eval out1 = (if arg1 = 0 then eval arg2 else eval arg3)
-//
-// Input Bounds:
-//   arg1: [0x0 ~> 0x1]
-//   arg2: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
-//   arg3: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
-// Output Bounds:
-//   out1: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
-func p521Selectznz(out1 *[9]uint64, arg1 p521Uint1, arg2 *[9]uint64, arg3 *[9]uint64) {
-	var x1 uint64
-	p521CmovznzU64(&x1, arg1, arg2[0], arg3[0])
-	var x2 uint64
-	p521CmovznzU64(&x2, arg1, arg2[1], arg3[1])
-	var x3 uint64
-	p521CmovznzU64(&x3, arg1, arg2[2], arg3[2])
-	var x4 uint64
-	p521CmovznzU64(&x4, arg1, arg2[3], arg3[3])
-	var x5 uint64
-	p521CmovznzU64(&x5, arg1, arg2[4], arg3[4])
-	var x6 uint64
-	p521CmovznzU64(&x6, arg1, arg2[5], arg3[5])
-	var x7 uint64
-	p521CmovznzU64(&x7, arg1, arg2[6], arg3[6])
-	var x8 uint64
-	p521CmovznzU64(&x8, arg1, arg2[7], arg3[7])
-	var x9 uint64
-	p521CmovznzU64(&x9, arg1, arg2[8], arg3[8])
-	out1[0] = x1
-	out1[1] = x2
-	out1[2] = x3
-	out1[3] = x4
-	out1[4] = x5
-	out1[5] = x6
-	out1[6] = x7
-	out1[7] = x8
-	out1[8] = x9
-}
-
-// p521ToBytes serializes a field element NOT in the Montgomery domain to bytes in little-endian order.
-//
-// Preconditions:
-//   0 ≤ eval arg1 < m
-// Postconditions:
-//   out1 = map (λ x, ⌊((eval arg1 mod m) mod 2^(8 * (x + 1))) / 2^(8 * x)⌋) [0..65]
-//
-// Input Bounds:
-//   arg1: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0x1ff]]
-// Output Bounds:
-//   out1: [[0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0x1]]
-func p521ToBytes(out1 *[66]uint8, arg1 *[9]uint64) {
-	x1 := arg1[8]
-	x2 := arg1[7]
-	x3 := arg1[6]
-	x4 := arg1[5]
-	x5 := arg1[4]
-	x6 := arg1[3]
-	x7 := arg1[2]
-	x8 := arg1[1]
-	x9 := arg1[0]
-	x10 := (uint8(x9) & 0xff)
-	x11 := (x9 >> 8)
-	x12 := (uint8(x11) & 0xff)
-	x13 := (x11 >> 8)
-	x14 := (uint8(x13) & 0xff)
-	x15 := (x13 >> 8)
-	x16 := (uint8(x15) & 0xff)
-	x17 := (x15 >> 8)
-	x18 := (uint8(x17) & 0xff)
-	x19 := (x17 >> 8)
-	x20 := (uint8(x19) & 0xff)
-	x21 := (x19 >> 8)
-	x22 := (uint8(x21) & 0xff)
-	x23 := uint8((x21 >> 8))
-	x24 := (uint8(x8) & 0xff)
-	x25 := (x8 >> 8)
-	x26 := (uint8(x25) & 0xff)
-	x27 := (x25 >> 8)
-	x28 := (uint8(x27) & 0xff)
-	x29 := (x27 >> 8)
-	x30 := (uint8(x29) & 0xff)
-	x31 := (x29 >> 8)
-	x32 := (uint8(x31) & 0xff)
-	x33 := (x31 >> 8)
-	x34 := (uint8(x33) & 0xff)
-	x35 := (x33 >> 8)
-	x36 := (uint8(x35) & 0xff)
-	x37 := uint8((x35 >> 8))
-	x38 := (uint8(x7) & 0xff)
-	x39 := (x7 >> 8)
-	x40 := (uint8(x39) & 0xff)
-	x41 := (x39 >> 8)
-	x42 := (uint8(x41) & 0xff)
-	x43 := (x41 >> 8)
-	x44 := (uint8(x43) & 0xff)
-	x45 := (x43 >> 8)
-	x46 := (uint8(x45) & 0xff)
-	x47 := (x45 >> 8)
-	x48 := (uint8(x47) & 0xff)
-	x49 := (x47 >> 8)
-	x50 := (uint8(x49) & 0xff)
-	x51 := uint8((x49 >> 8))
-	x52 := (uint8(x6) & 0xff)
-	x53 := (x6 >> 8)
-	x54 := (uint8(x53) & 0xff)
-	x55 := (x53 >> 8)
-	x56 := (uint8(x55) & 0xff)
-	x57 := (x55 >> 8)
-	x58 := (uint8(x57) & 0xff)
-	x59 := (x57 >> 8)
-	x60 := (uint8(x59) & 0xff)
-	x61 := (x59 >> 8)
-	x62 := (uint8(x61) & 0xff)
-	x63 := (x61 >> 8)
-	x64 := (uint8(x63) & 0xff)
-	x65 := uint8((x63 >> 8))
-	x66 := (uint8(x5) & 0xff)
-	x67 := (x5 >> 8)
-	x68 := (uint8(x67) & 0xff)
-	x69 := (x67 >> 8)
-	x70 := (uint8(x69) & 0xff)
-	x71 := (x69 >> 8)
-	x72 := (uint8(x71) & 0xff)
-	x73 := (x71 >> 8)
-	x74 := (uint8(x73) & 0xff)
-	x75 := (x73 >> 8)
-	x76 := (uint8(x75) & 0xff)
-	x77 := (x75 >> 8)
-	x78 := (uint8(x77) & 0xff)
-	x79 := uint8((x77 >> 8))
-	x80 := (uint8(x4) & 0xff)
-	x81 := (x4 >> 8)
-	x82 := (uint8(x81) & 0xff)
-	x83 := (x81 >> 8)
-	x84 := (uint8(x83) & 0xff)
-	x85 := (x83 >> 8)
-	x86 := (uint8(x85) & 0xff)
-	x87 := (x85 >> 8)
-	x88 := (uint8(x87) & 0xff)
-	x89 := (x87 >> 8)
-	x90 := (uint8(x89) & 0xff)
-	x91 := (x89 >> 8)
-	x92 := (uint8(x91) & 0xff)
-	x93 := uint8((x91 >> 8))
-	x94 := (uint8(x3) & 0xff)
-	x95 := (x3 >> 8)
-	x96 := (uint8(x95) & 0xff)
-	x97 := (x95 >> 8)
-	x98 := (uint8(x97) & 0xff)
-	x99 := (x97 >> 8)
-	x100 := (uint8(x99) & 0xff)
-	x101 := (x99 >> 8)
-	x102 := (uint8(x101) & 0xff)
-	x103 := (x101 >> 8)
-	x104 := (uint8(x103) & 0xff)
-	x105 := (x103 >> 8)
-	x106 := (uint8(x105) & 0xff)
-	x107 := uint8((x105 >> 8))
-	x108 := (uint8(x2) & 0xff)
-	x109 := (x2 >> 8)
-	x110 := (uint8(x109) & 0xff)
-	x111 := (x109 >> 8)
-	x112 := (uint8(x111) & 0xff)
-	x113 := (x111 >> 8)
-	x114 := (uint8(x113) & 0xff)
-	x115 := (x113 >> 8)
-	x116 := (uint8(x115) & 0xff)
-	x117 := (x115 >> 8)
-	x118 := (uint8(x117) & 0xff)
-	x119 := (x117 >> 8)
-	x120 := (uint8(x119) & 0xff)
-	x121 := uint8((x119 >> 8))
-	x122 := (uint8(x1) & 0xff)
-	x123 := p521Uint1((x1 >> 8))
-	out1[0] = x10
-	out1[1] = x12
-	out1[2] = x14
-	out1[3] = x16
-	out1[4] = x18
-	out1[5] = x20
-	out1[6] = x22
-	out1[7] = x23
-	out1[8] = x24
-	out1[9] = x26
-	out1[10] = x28
-	out1[11] = x30
-	out1[12] = x32
-	out1[13] = x34
-	out1[14] = x36
-	out1[15] = x37
-	out1[16] = x38
-	out1[17] = x40
-	out1[18] = x42
-	out1[19] = x44
-	out1[20] = x46
-	out1[21] = x48
-	out1[22] = x50
-	out1[23] = x51
-	out1[24] = x52
-	out1[25] = x54
-	out1[26] = x56
-	out1[27] = x58
-	out1[28] = x60
-	out1[29] = x62
-	out1[30] = x64
-	out1[31] = x65
-	out1[32] = x66
-	out1[33] = x68
-	out1[34] = x70
-	out1[35] = x72
-	out1[36] = x74
-	out1[37] = x76
-	out1[38] = x78
-	out1[39] = x79
-	out1[40] = x80
-	out1[41] = x82
-	out1[42] = x84
-	out1[43] = x86
-	out1[44] = x88
-	out1[45] = x90
-	out1[46] = x92
-	out1[47] = x93
-	out1[48] = x94
-	out1[49] = x96
-	out1[50] = x98
-	out1[51] = x100
-	out1[52] = x102
-	out1[53] = x104
-	out1[54] = x106
-	out1[55] = x107
-	out1[56] = x108
-	out1[57] = x110
-	out1[58] = x112
-	out1[59] = x114
-	out1[60] = x116
-	out1[61] = x118
-	out1[62] = x120
-	out1[63] = x121
-	out1[64] = x122
-	out1[65] = uint8(x123)
-}
-
-// p521FromBytes deserializes a field element NOT in the Montgomery domain from bytes in little-endian order.
-//
-// Preconditions:
-//   0 ≤ bytes_eval arg1 < m
-// Postconditions:
-//   eval out1 mod m = bytes_eval arg1 mod m
-//   0 ≤ eval out1 < m
-//
-// Input Bounds:
-//   arg1: [[0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0x1]]
-// Output Bounds:
-//   out1: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0x1ff]]
-func p521FromBytes(out1 *[9]uint64, arg1 *[66]uint8) {
-	x1 := (uint64(p521Uint1(arg1[65])) << 8)
-	x2 := arg1[64]
-	x3 := (uint64(arg1[63]) << 56)
-	x4 := (uint64(arg1[62]) << 48)
-	x5 := (uint64(arg1[61]) << 40)
-	x6 := (uint64(arg1[60]) << 32)
-	x7 := (uint64(arg1[59]) << 24)
-	x8 := (uint64(arg1[58]) << 16)
-	x9 := (uint64(arg1[57]) << 8)
-	x10 := arg1[56]
-	x11 := (uint64(arg1[55]) << 56)
-	x12 := (uint64(arg1[54]) << 48)
-	x13 := (uint64(arg1[53]) << 40)
-	x14 := (uint64(arg1[52]) << 32)
-	x15 := (uint64(arg1[51]) << 24)
-	x16 := (uint64(arg1[50]) << 16)
-	x17 := (uint64(arg1[49]) << 8)
-	x18 := arg1[48]
-	x19 := (uint64(arg1[47]) << 56)
-	x20 := (uint64(arg1[46]) << 48)
-	x21 := (uint64(arg1[45]) << 40)
-	x22 := (uint64(arg1[44]) << 32)
-	x23 := (uint64(arg1[43]) << 24)
-	x24 := (uint64(arg1[42]) << 16)
-	x25 := (uint64(arg1[41]) << 8)
-	x26 := arg1[40]
-	x27 := (uint64(arg1[39]) << 56)
-	x28 := (uint64(arg1[38]) << 48)
-	x29 := (uint64(arg1[37]) << 40)
-	x30 := (uint64(arg1[36]) << 32)
-	x31 := (uint64(arg1[35]) << 24)
-	x32 := (uint64(arg1[34]) << 16)
-	x33 := (uint64(arg1[33]) << 8)
-	x34 := arg1[32]
-	x35 := (uint64(arg1[31]) << 56)
-	x36 := (uint64(arg1[30]) << 48)
-	x37 := (uint64(arg1[29]) << 40)
-	x38 := (uint64(arg1[28]) << 32)
-	x39 := (uint64(arg1[27]) << 24)
-	x40 := (uint64(arg1[26]) << 16)
-	x41 := (uint64(arg1[25]) << 8)
-	x42 := arg1[24]
-	x43 := (uint64(arg1[23]) << 56)
-	x44 := (uint64(arg1[22]) << 48)
-	x45 := (uint64(arg1[21]) << 40)
-	x46 := (uint64(arg1[20]) << 32)
-	x47 := (uint64(arg1[19]) << 24)
-	x48 := (uint64(arg1[18]) << 16)
-	x49 := (uint64(arg1[17]) << 8)
-	x50 := arg1[16]
-	x51 := (uint64(arg1[15]) << 56)
-	x52 := (uint64(arg1[14]) << 48)
-	x53 := (uint64(arg1[13]) << 40)
-	x54 := (uint64(arg1[12]) << 32)
-	x55 := (uint64(arg1[11]) << 24)
-	x56 := (uint64(arg1[10]) << 16)
-	x57 := (uint64(arg1[9]) << 8)
-	x58 := arg1[8]
-	x59 := (uint64(arg1[7]) << 56)
-	x60 := (uint64(arg1[6]) << 48)
-	x61 := (uint64(arg1[5]) << 40)
-	x62 := (uint64(arg1[4]) << 32)
-	x63 := (uint64(arg1[3]) << 24)
-	x64 := (uint64(arg1[2]) << 16)
-	x65 := (uint64(arg1[1]) << 8)
-	x66 := arg1[0]
-	x67 := (x65 + uint64(x66))
-	x68 := (x64 + x67)
-	x69 := (x63 + x68)
-	x70 := (x62 + x69)
-	x71 := (x61 + x70)
-	x72 := (x60 + x71)
-	x73 := (x59 + x72)
-	x74 := (x57 + uint64(x58))
-	x75 := (x56 + x74)
-	x76 := (x55 + x75)
-	x77 := (x54 + x76)
-	x78 := (x53 + x77)
-	x79 := (x52 + x78)
-	x80 := (x51 + x79)
-	x81 := (x49 + uint64(x50))
-	x82 := (x48 + x81)
-	x83 := (x47 + x82)
-	x84 := (x46 + x83)
-	x85 := (x45 + x84)
-	x86 := (x44 + x85)
-	x87 := (x43 + x86)
-	x88 := (x41 + uint64(x42))
-	x89 := (x40 + x88)
-	x90 := (x39 + x89)
-	x91 := (x38 + x90)
-	x92 := (x37 + x91)
-	x93 := (x36 + x92)
-	x94 := (x35 + x93)
-	x95 := (x33 + uint64(x34))
-	x96 := (x32 + x95)
-	x97 := (x31 + x96)
-	x98 := (x30 + x97)
-	x99 := (x29 + x98)
-	x100 := (x28 + x99)
-	x101 := (x27 + x100)
-	x102 := (x25 + uint64(x26))
-	x103 := (x24 + x102)
-	x104 := (x23 + x103)
-	x105 := (x22 + x104)
-	x106 := (x21 + x105)
-	x107 := (x20 + x106)
-	x108 := (x19 + x107)
-	x109 := (x17 + uint64(x18))
-	x110 := (x16 + x109)
-	x111 := (x15 + x110)
-	x112 := (x14 + x111)
-	x113 := (x13 + x112)
-	x114 := (x12 + x113)
-	x115 := (x11 + x114)
-	x116 := (x9 + uint64(x10))
-	x117 := (x8 + x116)
-	x118 := (x7 + x117)
-	x119 := (x6 + x118)
-	x120 := (x5 + x119)
-	x121 := (x4 + x120)
-	x122 := (x3 + x121)
-	x123 := (x1 + uint64(x2))
-	out1[0] = x73
-	out1[1] = x80
-	out1[2] = x87
-	out1[3] = x94
-	out1[4] = x101
-	out1[5] = x108
-	out1[6] = x115
-	out1[7] = x122
-	out1[8] = x123
-}
diff --git a/contrib/go/_std_1.18/src/crypto/elliptic/internal/nistec/p224.go b/contrib/go/_std_1.18/src/crypto/elliptic/internal/nistec/p224.go
deleted file mode 100644
index 74dbc184dd..0000000000
--- a/contrib/go/_std_1.18/src/crypto/elliptic/internal/nistec/p224.go
+++ /dev/null
@@ -1,293 +0,0 @@
-// Copyright 2021 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package nistec
-
-import (
-	"crypto/elliptic/internal/fiat"
-	"crypto/subtle"
-	"errors"
-)
-
-var p224B, _ = new(fiat.P224Element).SetBytes([]byte{0xb4, 0x05, 0x0a, 0x85,
-	0x0c, 0x04, 0xb3, 0xab, 0xf5, 0x41, 0x32, 0x56, 0x50, 0x44, 0xb0, 0xb7,
-	0xd7, 0xbf, 0xd8, 0xba, 0x27, 0x0b, 0x39, 0x43, 0x23, 0x55, 0xff, 0xb4})
-
-var p224G, _ = NewP224Point().SetBytes([]byte{0x04,
-	0xb7, 0x0e, 0x0c, 0xbd, 0x6b, 0xb4, 0xbf, 0x7f, 0x32, 0x13, 0x90, 0xb9,
-	0x4a, 0x03, 0xc1, 0xd3, 0x56, 0xc2, 0x11, 0x22, 0x34, 0x32, 0x80, 0xd6,
-	0x11, 0x5c, 0x1d, 0x21, 0xbd, 0x37, 0x63, 0x88, 0xb5, 0xf7, 0x23, 0xfb,
-	0x4c, 0x22, 0xdf, 0xe6, 0xcd, 0x43, 0x75, 0xa0, 0x5a, 0x07, 0x47, 0x64,
-	0x44, 0xd5, 0x81, 0x99, 0x85, 0x0, 0x7e, 0x34})
-
-const p224ElementLength = 28
-
-// P224Point is a P-224 point. The zero value is NOT valid.
-type P224Point struct {
-	// The point is represented in projective coordinates (X:Y:Z),
-	// where x = X/Z and y = Y/Z.
-	x, y, z *fiat.P224Element
-}
-
-// NewP224Point returns a new P224Point representing the point at infinity point.
-func NewP224Point() *P224Point {
-	return &P224Point{
-		x: new(fiat.P224Element),
-		y: new(fiat.P224Element).One(),
-		z: new(fiat.P224Element),
-	}
-}
-
-// NewP224Generator returns a new P224Point set to the canonical generator.
-func NewP224Generator() *P224Point {
-	return (&P224Point{
-		x: new(fiat.P224Element),
-		y: new(fiat.P224Element),
-		z: new(fiat.P224Element),
-	}).Set(p224G)
-}
-
-// Set sets p = q and returns p.
-func (p *P224Point) Set(q *P224Point) *P224Point {
-	p.x.Set(q.x)
-	p.y.Set(q.y)
-	p.z.Set(q.z)
-	return p
-}
-
-// SetBytes sets p to the compressed, uncompressed, or infinity value encoded in
-// b, as specified in SEC 1, Version 2.0, Section 2.3.4. If the point is not on
-// the curve, it returns nil and an error, and the receiver is unchanged.
-// Otherwise, it returns p.
-func (p *P224Point) SetBytes(b []byte) (*P224Point, error) {
-	switch {
-	// Point at infinity.
-	case len(b) == 1 && b[0] == 0:
-		return p.Set(NewP224Point()), nil
-
-	// Uncompressed form.
-	case len(b) == 1+2*p224ElementLength && b[0] == 4:
-		x, err := new(fiat.P224Element).SetBytes(b[1 : 1+p224ElementLength])
-		if err != nil {
-			return nil, err
-		}
-		y, err := new(fiat.P224Element).SetBytes(b[1+p224ElementLength:])
-		if err != nil {
-			return nil, err
-		}
-		if err := p224CheckOnCurve(x, y); err != nil {
-			return nil, err
-		}
-		p.x.Set(x)
-		p.y.Set(y)
-		p.z.One()
-		return p, nil
-
-	// Compressed form
-	case len(b) == 1+p224ElementLength && b[0] == 0:
-		return nil, errors.New("unimplemented") // TODO(filippo)
-
-	default:
-		return nil, errors.New("invalid P224 point encoding")
-	}
-}
-
-func p224CheckOnCurve(x, y *fiat.P224Element) error {
-	// x³ - 3x + b.
-	x3 := new(fiat.P224Element).Square(x)
-	x3.Mul(x3, x)
-
-	threeX := new(fiat.P224Element).Add(x, x)
-	threeX.Add(threeX, x)
-
-	x3.Sub(x3, threeX)
-	x3.Add(x3, p224B)
-
-	// y² = x³ - 3x + b
-	y2 := new(fiat.P224Element).Square(y)
-
-	if x3.Equal(y2) != 1 {
-		return errors.New("P224 point not on curve")
-	}
-	return nil
-}
-
-// Bytes returns the uncompressed or infinity encoding of p, as specified in
-// SEC 1, Version 2.0, Section 2.3.3. Note that the encoding of the point at
-// infinity is shorter than all other encodings.
-func (p *P224Point) Bytes() []byte {
-	// This function is outlined to make the allocations inline in the caller
-	// rather than happen on the heap.
-	var out [133]byte
-	return p.bytes(&out)
-}
-
-func (p *P224Point) bytes(out *[133]byte) []byte {
-	if p.z.IsZero() == 1 {
-		return append(out[:0], 0)
-	}
-
-	zinv := new(fiat.P224Element).Invert(p.z)
-	xx := new(fiat.P224Element).Mul(p.x, zinv)
-	yy := new(fiat.P224Element).Mul(p.y, zinv)
-
-	buf := append(out[:0], 4)
-	buf = append(buf, xx.Bytes()...)
-	buf = append(buf, yy.Bytes()...)
-	return buf
-}
-
-// Add sets q = p1 + p2, and returns q. The points may overlap.
-func (q *P224Point) Add(p1, p2 *P224Point) *P224Point {
-	// Complete addition formula for a = -3 from "Complete addition formulas for
-	// prime order elliptic curves" (https://eprint.iacr.org/2015/1060), §A.2.
-
-	t0 := new(fiat.P224Element).Mul(p1.x, p2.x) // t0 := X1 * X2
-	t1 := new(fiat.P224Element).Mul(p1.y, p2.y) // t1 := Y1 * Y2
-	t2 := new(fiat.P224Element).Mul(p1.z, p2.z) // t2 := Z1 * Z2
-	t3 := new(fiat.P224Element).Add(p1.x, p1.y) // t3 := X1 + Y1
-	t4 := new(fiat.P224Element).Add(p2.x, p2.y) // t4 := X2 + Y2
-	t3.Mul(t3, t4)                              // t3 := t3 * t4
-	t4.Add(t0, t1)                              // t4 := t0 + t1
-	t3.Sub(t3, t4)                              // t3 := t3 - t4
-	t4.Add(p1.y, p1.z)                          // t4 := Y1 + Z1
-	x3 := new(fiat.P224Element).Add(p2.y, p2.z) // X3 := Y2 + Z2
-	t4.Mul(t4, x3)                              // t4 := t4 * X3
-	x3.Add(t1, t2)                              // X3 := t1 + t2
-	t4.Sub(t4, x3)                              // t4 := t4 - X3
-	x3.Add(p1.x, p1.z)                          // X3 := X1 + Z1
-	y3 := new(fiat.P224Element).Add(p2.x, p2.z) // Y3 := X2 + Z2
-	x3.Mul(x3, y3)                              // X3 := X3 * Y3
-	y3.Add(t0, t2)                              // Y3 := t0 + t2
-	y3.Sub(x3, y3)                              // Y3 := X3 - Y3
-	z3 := new(fiat.P224Element).Mul(p224B, t2)  // Z3 := b * t2
-	x3.Sub(y3, z3)                              // X3 := Y3 - Z3
-	z3.Add(x3, x3)                              // Z3 := X3 + X3
-	x3.Add(x3, z3)                              // X3 := X3 + Z3
-	z3.Sub(t1, x3)                              // Z3 := t1 - X3
-	x3.Add(t1, x3)                              // X3 := t1 + X3
-	y3.Mul(p224B, y3)                           // Y3 := b * Y3
-	t1.Add(t2, t2)                              // t1 := t2 + t2
-	t2.Add(t1, t2)                              // t2 := t1 + t2
-	y3.Sub(y3, t2)                              // Y3 := Y3 - t2
-	y3.Sub(y3, t0)                              // Y3 := Y3 - t0
-	t1.Add(y3, y3)                              // t1 := Y3 + Y3
-	y3.Add(t1, y3)                              // Y3 := t1 + Y3
-	t1.Add(t0, t0)                              // t1 := t0 + t0
-	t0.Add(t1, t0)                              // t0 := t1 + t0
-	t0.Sub(t0, t2)                              // t0 := t0 - t2
-	t1.Mul(t4, y3)                              // t1 := t4 * Y3
-	t2.Mul(t0, y3)                              // t2 := t0 * Y3
-	y3.Mul(x3, z3)                              // Y3 := X3 * Z3
-	y3.Add(y3, t2)                              // Y3 := Y3 + t2
-	x3.Mul(t3, x3)                              // X3 := t3 * X3
-	x3.Sub(x3, t1)                              // X3 := X3 - t1
-	z3.Mul(t4, z3)                              // Z3 := t4 * Z3
-	t1.Mul(t3, t0)                              // t1 := t3 * t0
-	z3.Add(z3, t1)                              // Z3 := Z3 + t1
-
-	q.x.Set(x3)
-	q.y.Set(y3)
-	q.z.Set(z3)
-	return q
-}
-
-// Double sets q = p + p, and returns q. The points may overlap.
-func (q *P224Point) Double(p *P224Point) *P224Point {
-	// Complete addition formula for a = -3 from "Complete addition formulas for
-	// prime order elliptic curves" (https://eprint.iacr.org/2015/1060), §A.2.
-
-	t0 := new(fiat.P224Element).Square(p.x)    // t0 := X ^ 2
-	t1 := new(fiat.P224Element).Square(p.y)    // t1 := Y ^ 2
-	t2 := new(fiat.P224Element).Square(p.z)    // t2 := Z ^ 2
-	t3 := new(fiat.P224Element).Mul(p.x, p.y)  // t3 := X * Y
-	t3.Add(t3, t3)                             // t3 := t3 + t3
-	z3 := new(fiat.P224Element).Mul(p.x, p.z)  // Z3 := X * Z
-	z3.Add(z3, z3)                             // Z3 := Z3 + Z3
-	y3 := new(fiat.P224Element).Mul(p224B, t2) // Y3 := b * t2
-	y3.Sub(y3, z3)                             // Y3 := Y3 - Z3
-	x3 := new(fiat.P224Element).Add(y3, y3)    // X3 := Y3 + Y3
-	y3.Add(x3, y3)                             // Y3 := X3 + Y3
-	x3.Sub(t1, y3)                             // X3 := t1 - Y3
-	y3.Add(t1, y3)                             // Y3 := t1 + Y3
-	y3.Mul(x3, y3)                             // Y3 := X3 * Y3
-	x3.Mul(x3, t3)                             // X3 := X3 * t3
-	t3.Add(t2, t2)                             // t3 := t2 + t2
-	t2.Add(t2, t3)                             // t2 := t2 + t3
-	z3.Mul(p224B, z3)                          // Z3 := b * Z3
-	z3.Sub(z3, t2)                             // Z3 := Z3 - t2
-	z3.Sub(z3, t0)                             // Z3 := Z3 - t0
-	t3.Add(z3, z3)                             // t3 := Z3 + Z3
-	z3.Add(z3, t3)                             // Z3 := Z3 + t3
-	t3.Add(t0, t0)                             // t3 := t0 + t0
-	t0.Add(t3, t0)                             // t0 := t3 + t0
-	t0.Sub(t0, t2)                             // t0 := t0 - t2
-	t0.Mul(t0, z3)                             // t0 := t0 * Z3
-	y3.Add(y3, t0)                             // Y3 := Y3 + t0
-	t0.Mul(p.y, p.z)                           // t0 := Y * Z
-	t0.Add(t0, t0)                             // t0 := t0 + t0
-	z3.Mul(t0, z3)                             // Z3 := t0 * Z3
-	x3.Sub(x3, z3)                             // X3 := X3 - Z3
-	z3.Mul(t0, t1)                             // Z3 := t0 * t1
-	z3.Add(z3, z3)                             // Z3 := Z3 + Z3
-	z3.Add(z3, z3)                             // Z3 := Z3 + Z3
-
-	q.x.Set(x3)
-	q.y.Set(y3)
-	q.z.Set(z3)
-	return q
-}
-
-// Select sets q to p1 if cond == 1, and to p2 if cond == 0.
-func (q *P224Point) Select(p1, p2 *P224Point, cond int) *P224Point {
-	q.x.Select(p1.x, p2.x, cond)
-	q.y.Select(p1.y, p2.y, cond)
-	q.z.Select(p1.z, p2.z, cond)
-	return q
-}
-
-// ScalarMult sets p = scalar * q, and returns p.
-func (p *P224Point) ScalarMult(q *P224Point, scalar []byte) *P224Point {
-	// table holds the first 16 multiples of q. The explicit newP224Point calls
-	// get inlined, letting the allocations live on the stack.
-	var table = [16]*P224Point{
-		NewP224Point(), NewP224Point(), NewP224Point(), NewP224Point(),
-		NewP224Point(), NewP224Point(), NewP224Point(), NewP224Point(),
-		NewP224Point(), NewP224Point(), NewP224Point(), NewP224Point(),
-		NewP224Point(), NewP224Point(), NewP224Point(), NewP224Point(),
-	}
-	for i := 1; i < 16; i++ {
-		table[i].Add(table[i-1], q)
-	}
-
-	// Instead of doing the classic double-and-add chain, we do it with a
-	// four-bit window: we double four times, and then add [0-15]P.
-	t := NewP224Point()
-	p.Set(NewP224Point())
-	for _, byte := range scalar {
-		p.Double(p)
-		p.Double(p)
-		p.Double(p)
-		p.Double(p)
-
-		for i := uint8(0); i < 16; i++ {
-			cond := subtle.ConstantTimeByteEq(byte>>4, i)
-			t.Select(table[i], t, cond)
-		}
-		p.Add(p, t)
-
-		p.Double(p)
-		p.Double(p)
-		p.Double(p)
-		p.Double(p)
-
-		for i := uint8(0); i < 16; i++ {
-			cond := subtle.ConstantTimeByteEq(byte&0b1111, i)
-			t.Select(table[i], t, cond)
-		}
-		p.Add(p, t)
-	}
-
-	return p
-}
diff --git a/contrib/go/_std_1.18/src/crypto/elliptic/internal/nistec/p384.go b/contrib/go/_std_1.18/src/crypto/elliptic/internal/nistec/p384.go
deleted file mode 100644
index 24a166de0a..0000000000
--- a/contrib/go/_std_1.18/src/crypto/elliptic/internal/nistec/p384.go
+++ /dev/null
@@ -1,298 +0,0 @@
-// Copyright 2021 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package nistec
-
-import (
-	"crypto/elliptic/internal/fiat"
-	"crypto/subtle"
-	"errors"
-)
-
-var p384B, _ = new(fiat.P384Element).SetBytes([]byte{
-	0xb3, 0x31, 0x2f, 0xa7, 0xe2, 0x3e, 0xe7, 0xe4, 0x98, 0x8e, 0x05, 0x6b,
-	0xe3, 0xf8, 0x2d, 0x19, 0x18, 0x1d, 0x9c, 0x6e, 0xfe, 0x81, 0x41, 0x12,
-	0x03, 0x14, 0x08, 0x8f, 0x50, 0x13, 0x87, 0x5a, 0xc6, 0x56, 0x39, 0x8d,
-	0x8a, 0x2e, 0xd1, 0x9d, 0x2a, 0x85, 0xc8, 0xed, 0xd3, 0xec, 0x2a, 0xef})
-
-var p384G, _ = NewP384Point().SetBytes([]byte{0x4,
-	0xaa, 0x87, 0xca, 0x22, 0xbe, 0x8b, 0x05, 0x37, 0x8e, 0xb1, 0xc7, 0x1e,
-	0xf3, 0x20, 0xad, 0x74, 0x6e, 0x1d, 0x3b, 0x62, 0x8b, 0xa7, 0x9b, 0x98,
-	0x59, 0xf7, 0x41, 0xe0, 0x82, 0x54, 0x2a, 0x38, 0x55, 0x02, 0xf2, 0x5d,
-	0xbf, 0x55, 0x29, 0x6c, 0x3a, 0x54, 0x5e, 0x38, 0x72, 0x76, 0x0a, 0xb7,
-	0x36, 0x17, 0xde, 0x4a, 0x96, 0x26, 0x2c, 0x6f, 0x5d, 0x9e, 0x98, 0xbf,
-	0x92, 0x92, 0xdc, 0x29, 0xf8, 0xf4, 0x1d, 0xbd, 0x28, 0x9a, 0x14, 0x7c,
-	0xe9, 0xda, 0x31, 0x13, 0xb5, 0xf0, 0xb8, 0xc0, 0x0a, 0x60, 0xb1, 0xce,
-	0x1d, 0x7e, 0x81, 0x9d, 0x7a, 0x43, 0x1d, 0x7c, 0x90, 0xea, 0x0e, 0x5f})
-
-const p384ElementLength = 48
-
-// P384Point is a P-384 point. The zero value is NOT valid.
-type P384Point struct {
-	// The point is represented in projective coordinates (X:Y:Z),
-	// where x = X/Z and y = Y/Z.
-	x, y, z *fiat.P384Element
-}
-
-// NewP384Point returns a new P384Point representing the point at infinity point.
-func NewP384Point() *P384Point {
-	return &P384Point{
-		x: new(fiat.P384Element),
-		y: new(fiat.P384Element).One(),
-		z: new(fiat.P384Element),
-	}
-}
-
-// NewP384Generator returns a new P384Point set to the canonical generator.
-func NewP384Generator() *P384Point {
-	return (&P384Point{
-		x: new(fiat.P384Element),
-		y: new(fiat.P384Element),
-		z: new(fiat.P384Element),
-	}).Set(p384G)
-}
-
-// Set sets p = q and returns p.
-func (p *P384Point) Set(q *P384Point) *P384Point {
-	p.x.Set(q.x)
-	p.y.Set(q.y)
-	p.z.Set(q.z)
-	return p
-}
-
-// SetBytes sets p to the compressed, uncompressed, or infinity value encoded in
-// b, as specified in SEC 1, Version 2.0, Section 2.3.4. If the point is not on
-// the curve, it returns nil and an error, and the receiver is unchanged.
-// Otherwise, it returns p.
-func (p *P384Point) SetBytes(b []byte) (*P384Point, error) {
-	switch {
-	// Point at infinity.
-	case len(b) == 1 && b[0] == 0:
-		return p.Set(NewP384Point()), nil
-
-	// Uncompressed form.
-	case len(b) == 1+2*p384ElementLength && b[0] == 4:
-		x, err := new(fiat.P384Element).SetBytes(b[1 : 1+p384ElementLength])
-		if err != nil {
-			return nil, err
-		}
-		y, err := new(fiat.P384Element).SetBytes(b[1+p384ElementLength:])
-		if err != nil {
-			return nil, err
-		}
-		if err := p384CheckOnCurve(x, y); err != nil {
-			return nil, err
-		}
-		p.x.Set(x)
-		p.y.Set(y)
-		p.z.One()
-		return p, nil
-
-	// Compressed form
-	case len(b) == 1+p384ElementLength && b[0] == 0:
-		return nil, errors.New("unimplemented") // TODO(filippo)
-
-	default:
-		return nil, errors.New("invalid P384 point encoding")
-	}
-}
-
-func p384CheckOnCurve(x, y *fiat.P384Element) error {
-	// x³ - 3x + b.
-	x3 := new(fiat.P384Element).Square(x)
-	x3.Mul(x3, x)
-
-	threeX := new(fiat.P384Element).Add(x, x)
-	threeX.Add(threeX, x)
-
-	x3.Sub(x3, threeX)
-	x3.Add(x3, p384B)
-
-	// y² = x³ - 3x + b
-	y2 := new(fiat.P384Element).Square(y)
-
-	if x3.Equal(y2) != 1 {
-		return errors.New("P384 point not on curve")
-	}
-	return nil
-}
-
-// Bytes returns the uncompressed or infinity encoding of p, as specified in
-// SEC 1, Version 2.0, Section 2.3.3. Note that the encoding of the point at
-// infinity is shorter than all other encodings.
-func (p *P384Point) Bytes() []byte {
-	// This function is outlined to make the allocations inline in the caller
-	// rather than happen on the heap.
-	var out [133]byte
-	return p.bytes(&out)
-}
-
-func (p *P384Point) bytes(out *[133]byte) []byte {
-	if p.z.IsZero() == 1 {
-		return append(out[:0], 0)
-	}
-
-	zinv := new(fiat.P384Element).Invert(p.z)
-	xx := new(fiat.P384Element).Mul(p.x, zinv)
-	yy := new(fiat.P384Element).Mul(p.y, zinv)
-
-	buf := append(out[:0], 4)
-	buf = append(buf, xx.Bytes()...)
-	buf = append(buf, yy.Bytes()...)
-	return buf
-}
-
-// Add sets q = p1 + p2, and returns q. The points may overlap.
-func (q *P384Point) Add(p1, p2 *P384Point) *P384Point {
-	// Complete addition formula for a = -3 from "Complete addition formulas for
-	// prime order elliptic curves" (https://eprint.iacr.org/2015/1060), §A.2.
-
-	t0 := new(fiat.P384Element).Mul(p1.x, p2.x) // t0 := X1 * X2
-	t1 := new(fiat.P384Element).Mul(p1.y, p2.y) // t1 := Y1 * Y2
-	t2 := new(fiat.P384Element).Mul(p1.z, p2.z) // t2 := Z1 * Z2
-	t3 := new(fiat.P384Element).Add(p1.x, p1.y) // t3 := X1 + Y1
-	t4 := new(fiat.P384Element).Add(p2.x, p2.y) // t4 := X2 + Y2
-	t3.Mul(t3, t4)                              // t3 := t3 * t4
-	t4.Add(t0, t1)                              // t4 := t0 + t1
-	t3.Sub(t3, t4)                              // t3 := t3 - t4
-	t4.Add(p1.y, p1.z)                          // t4 := Y1 + Z1
-	x3 := new(fiat.P384Element).Add(p2.y, p2.z) // X3 := Y2 + Z2
-	t4.Mul(t4, x3)                              // t4 := t4 * X3
-	x3.Add(t1, t2)                              // X3 := t1 + t2
-	t4.Sub(t4, x3)                              // t4 := t4 - X3
-	x3.Add(p1.x, p1.z)                          // X3 := X1 + Z1
-	y3 := new(fiat.P384Element).Add(p2.x, p2.z) // Y3 := X2 + Z2
-	x3.Mul(x3, y3)                              // X3 := X3 * Y3
-	y3.Add(t0, t2)                              // Y3 := t0 + t2
-	y3.Sub(x3, y3)                              // Y3 := X3 - Y3
-	z3 := new(fiat.P384Element).Mul(p384B, t2)  // Z3 := b * t2
-	x3.Sub(y3, z3)                              // X3 := Y3 - Z3
-	z3.Add(x3, x3)                              // Z3 := X3 + X3
-	x3.Add(x3, z3)                              // X3 := X3 + Z3
-	z3.Sub(t1, x3)                              // Z3 := t1 - X3
-	x3.Add(t1, x3)                              // X3 := t1 + X3
-	y3.Mul(p384B, y3)                           // Y3 := b * Y3
-	t1.Add(t2, t2)                              // t1 := t2 + t2
-	t2.Add(t1, t2)                              // t2 := t1 + t2
-	y3.Sub(y3, t2)                              // Y3 := Y3 - t2
-	y3.Sub(y3, t0)                              // Y3 := Y3 - t0
-	t1.Add(y3, y3)                              // t1 := Y3 + Y3
-	y3.Add(t1, y3)                              // Y3 := t1 + Y3
-	t1.Add(t0, t0)                              // t1 := t0 + t0
-	t0.Add(t1, t0)                              // t0 := t1 + t0
-	t0.Sub(t0, t2)                              // t0 := t0 - t2
-	t1.Mul(t4, y3)                              // t1 := t4 * Y3
-	t2.Mul(t0, y3)                              // t2 := t0 * Y3
-	y3.Mul(x3, z3)                              // Y3 := X3 * Z3
-	y3.Add(y3, t2)                              // Y3 := Y3 + t2
-	x3.Mul(t3, x3)                              // X3 := t3 * X3
-	x3.Sub(x3, t1)                              // X3 := X3 - t1
-	z3.Mul(t4, z3)                              // Z3 := t4 * Z3
-	t1.Mul(t3, t0)                              // t1 := t3 * t0
-	z3.Add(z3, t1)                              // Z3 := Z3 + t1
-
-	q.x.Set(x3)
-	q.y.Set(y3)
-	q.z.Set(z3)
-	return q
-}
-
-// Double sets q = p + p, and returns q. The points may overlap.
-func (q *P384Point) Double(p *P384Point) *P384Point {
-	// Complete addition formula for a = -3 from "Complete addition formulas for
-	// prime order elliptic curves" (https://eprint.iacr.org/2015/1060), §A.2.
-
-	t0 := new(fiat.P384Element).Square(p.x)    // t0 := X ^ 2
-	t1 := new(fiat.P384Element).Square(p.y)    // t1 := Y ^ 2
-	t2 := new(fiat.P384Element).Square(p.z)    // t2 := Z ^ 2
-	t3 := new(fiat.P384Element).Mul(p.x, p.y)  // t3 := X * Y
-	t3.Add(t3, t3)                             // t3 := t3 + t3
-	z3 := new(fiat.P384Element).Mul(p.x, p.z)  // Z3 := X * Z
-	z3.Add(z3, z3)                             // Z3 := Z3 + Z3
-	y3 := new(fiat.P384Element).Mul(p384B, t2) // Y3 := b * t2
-	y3.Sub(y3, z3)                             // Y3 := Y3 - Z3
-	x3 := new(fiat.P384Element).Add(y3, y3)    // X3 := Y3 + Y3
-	y3.Add(x3, y3)                             // Y3 := X3 + Y3
-	x3.Sub(t1, y3)                             // X3 := t1 - Y3
-	y3.Add(t1, y3)                             // Y3 := t1 + Y3
-	y3.Mul(x3, y3)                             // Y3 := X3 * Y3
-	x3.Mul(x3, t3)                             // X3 := X3 * t3
-	t3.Add(t2, t2)                             // t3 := t2 + t2
-	t2.Add(t2, t3)                             // t2 := t2 + t3
-	z3.Mul(p384B, z3)                          // Z3 := b * Z3
-	z3.Sub(z3, t2)                             // Z3 := Z3 - t2
-	z3.Sub(z3, t0)                             // Z3 := Z3 - t0
-	t3.Add(z3, z3)                             // t3 := Z3 + Z3
-	z3.Add(z3, t3)                             // Z3 := Z3 + t3
-	t3.Add(t0, t0)                             // t3 := t0 + t0
-	t0.Add(t3, t0)                             // t0 := t3 + t0
-	t0.Sub(t0, t2)                             // t0 := t0 - t2
-	t0.Mul(t0, z3)                             // t0 := t0 * Z3
-	y3.Add(y3, t0)                             // Y3 := Y3 + t0
-	t0.Mul(p.y, p.z)                           // t0 := Y * Z
-	t0.Add(t0, t0)                             // t0 := t0 + t0
-	z3.Mul(t0, z3)                             // Z3 := t0 * Z3
-	x3.Sub(x3, z3)                             // X3 := X3 - Z3
-	z3.Mul(t0, t1)                             // Z3 := t0 * t1
-	z3.Add(z3, z3)                             // Z3 := Z3 + Z3
-	z3.Add(z3, z3)                             // Z3 := Z3 + Z3
-
-	q.x.Set(x3)
-	q.y.Set(y3)
-	q.z.Set(z3)
-	return q
-}
-
-// Select sets q to p1 if cond == 1, and to p2 if cond == 0.
-func (q *P384Point) Select(p1, p2 *P384Point, cond int) *P384Point {
-	q.x.Select(p1.x, p2.x, cond)
-	q.y.Select(p1.y, p2.y, cond)
-	q.z.Select(p1.z, p2.z, cond)
-	return q
-}
-
-// ScalarMult sets p = scalar * q, and returns p.
-func (p *P384Point) ScalarMult(q *P384Point, scalar []byte) *P384Point {
-	// table holds the first 16 multiples of q. The explicit newP384Point calls
-	// get inlined, letting the allocations live on the stack.
-	var table = [16]*P384Point{
-		NewP384Point(), NewP384Point(), NewP384Point(), NewP384Point(),
-		NewP384Point(), NewP384Point(), NewP384Point(), NewP384Point(),
-		NewP384Point(), NewP384Point(), NewP384Point(), NewP384Point(),
-		NewP384Point(), NewP384Point(), NewP384Point(), NewP384Point(),
-	}
-	for i := 1; i < 16; i++ {
-		table[i].Add(table[i-1], q)
-	}
-
-	// Instead of doing the classic double-and-add chain, we do it with a
-	// four-bit window: we double four times, and then add [0-15]P.
-	t := NewP384Point()
-	p.Set(NewP384Point())
-	for _, byte := range scalar {
-		p.Double(p)
-		p.Double(p)
-		p.Double(p)
-		p.Double(p)
-
-		for i := uint8(0); i < 16; i++ {
-			cond := subtle.ConstantTimeByteEq(byte>>4, i)
-			t.Select(table[i], t, cond)
-		}
-		p.Add(p, t)
-
-		p.Double(p)
-		p.Double(p)
-		p.Double(p)
-		p.Double(p)
-
-		for i := uint8(0); i < 16; i++ {
-			cond := subtle.ConstantTimeByteEq(byte&0b1111, i)
-			t.Select(table[i], t, cond)
-		}
-		p.Add(p, t)
-	}
-
-	return p
-}
diff --git a/contrib/go/_std_1.18/src/crypto/elliptic/internal/nistec/p521.go b/contrib/go/_std_1.18/src/crypto/elliptic/internal/nistec/p521.go
deleted file mode 100644
index cdbd195cf4..0000000000
--- a/contrib/go/_std_1.18/src/crypto/elliptic/internal/nistec/p521.go
+++ /dev/null
@@ -1,310 +0,0 @@
-// Copyright 2021 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package nistec implements the NIST P elliptic curves from FIPS 186-4.
-//
-// This package uses fiat-crypto for its backend field arithmetic (not math/big)
-// and exposes constant-time, heap allocation-free, byte slice-based safe APIs.
-// Group operations use modern and safe complete addition formulas. The point at
-// infinity is handled and encoded according to SEC 1, Version 2.0, and invalid
-// curve points can't be represented.
-package nistec
-
-import (
-	"crypto/elliptic/internal/fiat"
-	"crypto/subtle"
-	"errors"
-)
-
-var p521B, _ = new(fiat.P521Element).SetBytes([]byte{
-	0x00, 0x51, 0x95, 0x3e, 0xb9, 0x61, 0x8e, 0x1c, 0x9a, 0x1f, 0x92, 0x9a,
-	0x21, 0xa0, 0xb6, 0x85, 0x40, 0xee, 0xa2, 0xda, 0x72, 0x5b, 0x99, 0xb3,
-	0x15, 0xf3, 0xb8, 0xb4, 0x89, 0x91, 0x8e, 0xf1, 0x09, 0xe1, 0x56, 0x19,
-	0x39, 0x51, 0xec, 0x7e, 0x93, 0x7b, 0x16, 0x52, 0xc0, 0xbd, 0x3b, 0xb1,
-	0xbf, 0x07, 0x35, 0x73, 0xdf, 0x88, 0x3d, 0x2c, 0x34, 0xf1, 0xef, 0x45,
-	0x1f, 0xd4, 0x6b, 0x50, 0x3f, 0x00})
-
-var p521G, _ = NewP521Point().SetBytes([]byte{0x04,
-	0x00, 0xc6, 0x85, 0x8e, 0x06, 0xb7, 0x04, 0x04, 0xe9, 0xcd, 0x9e, 0x3e,
-	0xcb, 0x66, 0x23, 0x95, 0xb4, 0x42, 0x9c, 0x64, 0x81, 0x39, 0x05, 0x3f,
-	0xb5, 0x21, 0xf8, 0x28, 0xaf, 0x60, 0x6b, 0x4d, 0x3d, 0xba, 0xa1, 0x4b,
-	0x5e, 0x77, 0xef, 0xe7, 0x59, 0x28, 0xfe, 0x1d, 0xc1, 0x27, 0xa2, 0xff,
-	0xa8, 0xde, 0x33, 0x48, 0xb3, 0xc1, 0x85, 0x6a, 0x42, 0x9b, 0xf9, 0x7e,
-	0x7e, 0x31, 0xc2, 0xe5, 0xbd, 0x66, 0x01, 0x18, 0x39, 0x29, 0x6a, 0x78,
-	0x9a, 0x3b, 0xc0, 0x04, 0x5c, 0x8a, 0x5f, 0xb4, 0x2c, 0x7d, 0x1b, 0xd9,
-	0x98, 0xf5, 0x44, 0x49, 0x57, 0x9b, 0x44, 0x68, 0x17, 0xaf, 0xbd, 0x17,
-	0x27, 0x3e, 0x66, 0x2c, 0x97, 0xee, 0x72, 0x99, 0x5e, 0xf4, 0x26, 0x40,
-	0xc5, 0x50, 0xb9, 0x01, 0x3f, 0xad, 0x07, 0x61, 0x35, 0x3c, 0x70, 0x86,
-	0xa2, 0x72, 0xc2, 0x40, 0x88, 0xbe, 0x94, 0x76, 0x9f, 0xd1, 0x66, 0x50})
-
-const p521ElementLength = 66
-
-// P521Point is a P-521 point. The zero value is NOT valid.
-type P521Point struct {
-	// The point is represented in projective coordinates (X:Y:Z),
-	// where x = X/Z and y = Y/Z.
-	x, y, z *fiat.P521Element
-}
-
-// NewP521Point returns a new P521Point representing the point at infinity point.
-func NewP521Point() *P521Point {
-	return &P521Point{
-		x: new(fiat.P521Element),
-		y: new(fiat.P521Element).One(),
-		z: new(fiat.P521Element),
-	}
-}
-
-// NewP521Generator returns a new P521Point set to the canonical generator.
-func NewP521Generator() *P521Point {
-	return (&P521Point{
-		x: new(fiat.P521Element),
-		y: new(fiat.P521Element),
-		z: new(fiat.P521Element),
-	}).Set(p521G)
-}
-
-// Set sets p = q and returns p.
-func (p *P521Point) Set(q *P521Point) *P521Point {
-	p.x.Set(q.x)
-	p.y.Set(q.y)
-	p.z.Set(q.z)
-	return p
-}
-
-// SetBytes sets p to the compressed, uncompressed, or infinity value encoded in
-// b, as specified in SEC 1, Version 2.0, Section 2.3.4. If the point is not on
-// the curve, it returns nil and an error, and the receiver is unchanged.
-// Otherwise, it returns p.
-func (p *P521Point) SetBytes(b []byte) (*P521Point, error) {
-	switch {
-	// Point at infinity.
-	case len(b) == 1 && b[0] == 0:
-		return p.Set(NewP521Point()), nil
-
-	// Uncompressed form.
-	case len(b) == 1+2*p521ElementLength && b[0] == 4:
-		x, err := new(fiat.P521Element).SetBytes(b[1 : 1+p521ElementLength])
-		if err != nil {
-			return nil, err
-		}
-		y, err := new(fiat.P521Element).SetBytes(b[1+p521ElementLength:])
-		if err != nil {
-			return nil, err
-		}
-		if err := p521CheckOnCurve(x, y); err != nil {
-			return nil, err
-		}
-		p.x.Set(x)
-		p.y.Set(y)
-		p.z.One()
-		return p, nil
-
-	// Compressed form
-	case len(b) == 1+p521ElementLength && b[0] == 0:
-		return nil, errors.New("unimplemented") // TODO(filippo)
-
-	default:
-		return nil, errors.New("invalid P521 point encoding")
-	}
-}
-
-func p521CheckOnCurve(x, y *fiat.P521Element) error {
-	// x³ - 3x + b.
-	x3 := new(fiat.P521Element).Square(x)
-	x3.Mul(x3, x)
-
-	threeX := new(fiat.P521Element).Add(x, x)
-	threeX.Add(threeX, x)
-
-	x3.Sub(x3, threeX)
-	x3.Add(x3, p521B)
-
-	// y² = x³ - 3x + b
-	y2 := new(fiat.P521Element).Square(y)
-
-	if x3.Equal(y2) != 1 {
-		return errors.New("P521 point not on curve")
-	}
-	return nil
-}
-
-// Bytes returns the uncompressed or infinity encoding of p, as specified in
-// SEC 1, Version 2.0, Section 2.3.3. Note that the encoding of the point at
-// infinity is shorter than all other encodings.
-func (p *P521Point) Bytes() []byte {
-	// This function is outlined to make the allocations inline in the caller
-	// rather than happen on the heap.
-	var out [133]byte
-	return p.bytes(&out)
-}
-
-func (p *P521Point) bytes(out *[133]byte) []byte {
-	if p.z.IsZero() == 1 {
-		return append(out[:0], 0)
-	}
-
-	zinv := new(fiat.P521Element).Invert(p.z)
-	xx := new(fiat.P521Element).Mul(p.x, zinv)
-	yy := new(fiat.P521Element).Mul(p.y, zinv)
-
-	buf := append(out[:0], 4)
-	buf = append(buf, xx.Bytes()...)
-	buf = append(buf, yy.Bytes()...)
-	return buf
-}
-
-// Add sets q = p1 + p2, and returns q. The points may overlap.
-func (q *P521Point) Add(p1, p2 *P521Point) *P521Point {
-	// Complete addition formula for a = -3 from "Complete addition formulas for
-	// prime order elliptic curves" (https://eprint.iacr.org/2015/1060), §A.2.
-
-	t0 := new(fiat.P521Element).Mul(p1.x, p2.x) // t0 := X1 * X2
-	t1 := new(fiat.P521Element).Mul(p1.y, p2.y) // t1 := Y1 * Y2
-	t2 := new(fiat.P521Element).Mul(p1.z, p2.z) // t2 := Z1 * Z2
-	t3 := new(fiat.P521Element).Add(p1.x, p1.y) // t3 := X1 + Y1
-	t4 := new(fiat.P521Element).Add(p2.x, p2.y) // t4 := X2 + Y2
-	t3.Mul(t3, t4)                              // t3 := t3 * t4
-	t4.Add(t0, t1)                              // t4 := t0 + t1
-	t3.Sub(t3, t4)                              // t3 := t3 - t4
-	t4.Add(p1.y, p1.z)                          // t4 := Y1 + Z1
-	x3 := new(fiat.P521Element).Add(p2.y, p2.z) // X3 := Y2 + Z2
-	t4.Mul(t4, x3)                              // t4 := t4 * X3
-	x3.Add(t1, t2)                              // X3 := t1 + t2
-	t4.Sub(t4, x3)                              // t4 := t4 - X3
-	x3.Add(p1.x, p1.z)                          // X3 := X1 + Z1
-	y3 := new(fiat.P521Element).Add(p2.x, p2.z) // Y3 := X2 + Z2
-	x3.Mul(x3, y3)                              // X3 := X3 * Y3
-	y3.Add(t0, t2)                              // Y3 := t0 + t2
-	y3.Sub(x3, y3)                              // Y3 := X3 - Y3
-	z3 := new(fiat.P521Element).Mul(p521B, t2)  // Z3 := b * t2
-	x3.Sub(y3, z3)                              // X3 := Y3 - Z3
-	z3.Add(x3, x3)                              // Z3 := X3 + X3
-	x3.Add(x3, z3)                              // X3 := X3 + Z3
-	z3.Sub(t1, x3)                              // Z3 := t1 - X3
-	x3.Add(t1, x3)                              // X3 := t1 + X3
-	y3.Mul(p521B, y3)                           // Y3 := b * Y3
-	t1.Add(t2, t2)                              // t1 := t2 + t2
-	t2.Add(t1, t2)                              // t2 := t1 + t2
-	y3.Sub(y3, t2)                              // Y3 := Y3 - t2
-	y3.Sub(y3, t0)                              // Y3 := Y3 - t0
-	t1.Add(y3, y3)                              // t1 := Y3 + Y3
-	y3.Add(t1, y3)                              // Y3 := t1 + Y3
-	t1.Add(t0, t0)                              // t1 := t0 + t0
-	t0.Add(t1, t0)                              // t0 := t1 + t0
-	t0.Sub(t0, t2)                              // t0 := t0 - t2
-	t1.Mul(t4, y3)                              // t1 := t4 * Y3
-	t2.Mul(t0, y3)                              // t2 := t0 * Y3
-	y3.Mul(x3, z3)                              // Y3 := X3 * Z3
-	y3.Add(y3, t2)                              // Y3 := Y3 + t2
-	x3.Mul(t3, x3)                              // X3 := t3 * X3
-	x3.Sub(x3, t1)                              // X3 := X3 - t1
-	z3.Mul(t4, z3)                              // Z3 := t4 * Z3
-	t1.Mul(t3, t0)                              // t1 := t3 * t0
-	z3.Add(z3, t1)                              // Z3 := Z3 + t1
-
-	q.x.Set(x3)
-	q.y.Set(y3)
-	q.z.Set(z3)
-	return q
-}
-
-// Double sets q = p + p, and returns q. The points may overlap.
-func (q *P521Point) Double(p *P521Point) *P521Point {
-	// Complete addition formula for a = -3 from "Complete addition formulas for
-	// prime order elliptic curves" (https://eprint.iacr.org/2015/1060), §A.2.
-
-	t0 := new(fiat.P521Element).Square(p.x)    // t0 := X ^ 2
-	t1 := new(fiat.P521Element).Square(p.y)    // t1 := Y ^ 2
-	t2 := new(fiat.P521Element).Square(p.z)    // t2 := Z ^ 2
-	t3 := new(fiat.P521Element).Mul(p.x, p.y)  // t3 := X * Y
-	t3.Add(t3, t3)                             // t3 := t3 + t3
-	z3 := new(fiat.P521Element).Mul(p.x, p.z)  // Z3 := X * Z
-	z3.Add(z3, z3)                             // Z3 := Z3 + Z3
-	y3 := new(fiat.P521Element).Mul(p521B, t2) // Y3 := b * t2
-	y3.Sub(y3, z3)                             // Y3 := Y3 - Z3
-	x3 := new(fiat.P521Element).Add(y3, y3)    // X3 := Y3 + Y3
-	y3.Add(x3, y3)                             // Y3 := X3 + Y3
-	x3.Sub(t1, y3)                             // X3 := t1 - Y3
-	y3.Add(t1, y3)                             // Y3 := t1 + Y3
-	y3.Mul(x3, y3)                             // Y3 := X3 * Y3
-	x3.Mul(x3, t3)                             // X3 := X3 * t3
-	t3.Add(t2, t2)                             // t3 := t2 + t2
-	t2.Add(t2, t3)                             // t2 := t2 + t3
-	z3.Mul(p521B, z3)                          // Z3 := b * Z3
-	z3.Sub(z3, t2)                             // Z3 := Z3 - t2
-	z3.Sub(z3, t0)                             // Z3 := Z3 - t0
-	t3.Add(z3, z3)                             // t3 := Z3 + Z3
-	z3.Add(z3, t3)                             // Z3 := Z3 + t3
-	t3.Add(t0, t0)                             // t3 := t0 + t0
-	t0.Add(t3, t0)                             // t0 := t3 + t0
-	t0.Sub(t0, t2)                             // t0 := t0 - t2
-	t0.Mul(t0, z3)                             // t0 := t0 * Z3
-	y3.Add(y3, t0)                             // Y3 := Y3 + t0
-	t0.Mul(p.y, p.z)                           // t0 := Y * Z
-	t0.Add(t0, t0)                             // t0 := t0 + t0
-	z3.Mul(t0, z3)                             // Z3 := t0 * Z3
-	x3.Sub(x3, z3)                             // X3 := X3 - Z3
-	z3.Mul(t0, t1)                             // Z3 := t0 * t1
-	z3.Add(z3, z3)                             // Z3 := Z3 + Z3
-	z3.Add(z3, z3)                             // Z3 := Z3 + Z3
-
-	q.x.Set(x3)
-	q.y.Set(y3)
-	q.z.Set(z3)
-	return q
-}
-
-// Select sets q to p1 if cond == 1, and to p2 if cond == 0.
-func (q *P521Point) Select(p1, p2 *P521Point, cond int) *P521Point {
-	q.x.Select(p1.x, p2.x, cond)
-	q.y.Select(p1.y, p2.y, cond)
-	q.z.Select(p1.z, p2.z, cond)
-	return q
-}
-
-// ScalarMult sets p = scalar * q, and returns p.
-func (p *P521Point) ScalarMult(q *P521Point, scalar []byte) *P521Point {
-	// table holds the first 16 multiples of q. The explicit newP521Point calls
-	// get inlined, letting the allocations live on the stack.
-	var table = [16]*P521Point{
-		NewP521Point(), NewP521Point(), NewP521Point(), NewP521Point(),
-		NewP521Point(), NewP521Point(), NewP521Point(), NewP521Point(),
-		NewP521Point(), NewP521Point(), NewP521Point(), NewP521Point(),
-		NewP521Point(), NewP521Point(), NewP521Point(), NewP521Point(),
-	}
-	for i := 1; i < 16; i++ {
-		table[i].Add(table[i-1], q)
-	}
-
-	// Instead of doing the classic double-and-add chain, we do it with a
-	// four-bit window: we double four times, and then add [0-15]P.
-	t := NewP521Point()
-	p.Set(NewP521Point())
-	for _, byte := range scalar {
-		p.Double(p)
-		p.Double(p)
-		p.Double(p)
-		p.Double(p)
-
-		for i := uint8(0); i < 16; i++ {
-			cond := subtle.ConstantTimeByteEq(byte>>4, i)
-			t.Select(table[i], t, cond)
-		}
-		p.Add(p, t)
-
-		p.Double(p)
-		p.Double(p)
-		p.Double(p)
-		p.Double(p)
-
-		for i := uint8(0); i < 16; i++ {
-			cond := subtle.ConstantTimeByteEq(byte&0b1111, i)
-			t.Select(table[i], t, cond)
-		}
-		p.Add(p, t)
-	}
-
-	return p
-}
diff --git a/contrib/go/_std_1.18/src/crypto/elliptic/p224.go b/contrib/go/_std_1.18/src/crypto/elliptic/p224.go
deleted file mode 100644
index 8a431c4769..0000000000
--- a/contrib/go/_std_1.18/src/crypto/elliptic/p224.go
+++ /dev/null
@@ -1,139 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package elliptic
-
-import (
-	"crypto/elliptic/internal/nistec"
-	"crypto/rand"
-	"math/big"
-)
-
-// p224Curve is a Curve implementation based on nistec.P224Point.
-//
-// It's a wrapper that exposes the big.Int-based Curve interface and encodes the
-// legacy idiosyncrasies it requires, such as invalid and infinity point
-// handling.
-//
-// To interact with the nistec package, points are encoded into and decoded from
-// properly formatted byte slices. All big.Int use is limited to this package.
-// Encoding and decoding is 1/1000th of the runtime of a scalar multiplication,
-// so the overhead is acceptable.
-type p224Curve struct {
-	params *CurveParams
-}
-
-var p224 p224Curve
-var _ Curve = p224
-
-func initP224() {
-	p224.params = &CurveParams{
-		Name:    "P-224",
-		BitSize: 224,
-		// FIPS 186-4, section D.1.2.2
-		P:  bigFromDecimal("26959946667150639794667015087019630673557916260026308143510066298881"),
-		N:  bigFromDecimal("26959946667150639794667015087019625940457807714424391721682722368061"),
-		B:  bigFromHex("b4050a850c04b3abf54132565044b0b7d7bfd8ba270b39432355ffb4"),
-		Gx: bigFromHex("b70e0cbd6bb4bf7f321390b94a03c1d356c21122343280d6115c1d21"),
-		Gy: bigFromHex("bd376388b5f723fb4c22dfe6cd4375a05a07476444d5819985007e34"),
-	}
-}
-
-func (curve p224Curve) Params() *CurveParams {
-	return curve.params
-}
-
-func (curve p224Curve) IsOnCurve(x, y *big.Int) bool {
-	// IsOnCurve is documented to reject (0, 0), the conventional point at
-	// infinity, which however is accepted by p224PointFromAffine.
-	if x.Sign() == 0 && y.Sign() == 0 {
-		return false
-	}
-	_, ok := p224PointFromAffine(x, y)
-	return ok
-}
-
-func p224PointFromAffine(x, y *big.Int) (p *nistec.P224Point, ok bool) {
-	// (0, 0) is by convention the point at infinity, which can't be represented
-	// in affine coordinates. Marshal incorrectly encodes it as an uncompressed
-	// point, which SetBytes would correctly reject. See Issue 37294.
-	if x.Sign() == 0 && y.Sign() == 0 {
-		return nistec.NewP224Point(), true
-	}
-	if x.Sign() < 0 || y.Sign() < 0 {
-		return nil, false
-	}
-	if x.BitLen() > 224 || y.BitLen() > 224 {
-		return nil, false
-	}
-	p, err := nistec.NewP224Point().SetBytes(Marshal(P224(), x, y))
-	if err != nil {
-		return nil, false
-	}
-	return p, true
-}
-
-func p224PointToAffine(p *nistec.P224Point) (x, y *big.Int) {
-	out := p.Bytes()
-	if len(out) == 1 && out[0] == 0 {
-		// This is the correct encoding of the point at infinity, which
-		// Unmarshal does not support. See Issue 37294.
-		return new(big.Int), new(big.Int)
-	}
-	x, y = Unmarshal(P224(), out)
-	if x == nil {
-		panic("crypto/elliptic: internal error: Unmarshal rejected a valid point encoding")
-	}
-	return x, y
-}
-
-// p224RandomPoint returns a random point on the curve. It's used when Add,
-// Double, or ScalarMult are fed a point not on the curve, which is undefined
-// behavior. Originally, we used to do the math on it anyway (which allows
-// invalid curve attacks) and relied on the caller and Unmarshal to avoid this
-// happening in the first place. Now, we just can't construct a nistec.P224Point
-// for an invalid pair of coordinates, because that API is safer. If we panic,
-// we risk introducing a DoS. If we return nil, we risk a panic. If we return
-// the input, ecdsa.Verify might fail open. The safest course seems to be to
-// return a valid, random point, which hopefully won't help the attacker.
-func p224RandomPoint() (x, y *big.Int) {
-	_, x, y, err := GenerateKey(P224(), rand.Reader)
-	if err != nil {
-		panic("crypto/elliptic: failed to generate random point")
-	}
-	return x, y
-}
-
-func (p224Curve) Add(x1, y1, x2, y2 *big.Int) (*big.Int, *big.Int) {
-	p1, ok := p224PointFromAffine(x1, y1)
-	if !ok {
-		return p224RandomPoint()
-	}
-	p2, ok := p224PointFromAffine(x2, y2)
-	if !ok {
-		return p224RandomPoint()
-	}
-	return p224PointToAffine(p1.Add(p1, p2))
-}
-
-func (p224Curve) Double(x1, y1 *big.Int) (*big.Int, *big.Int) {
-	p, ok := p224PointFromAffine(x1, y1)
-	if !ok {
-		return p224RandomPoint()
-	}
-	return p224PointToAffine(p.Double(p))
-}
-
-func (p224Curve) ScalarMult(Bx, By *big.Int, scalar []byte) (*big.Int, *big.Int) {
-	p, ok := p224PointFromAffine(Bx, By)
-	if !ok {
-		return p224RandomPoint()
-	}
-	return p224PointToAffine(p.ScalarMult(p, scalar))
-}
-
-func (p224Curve) ScalarBaseMult(scalar []byte) (*big.Int, *big.Int) {
-	p := nistec.NewP224Generator()
-	return p224PointToAffine(p.ScalarMult(p, scalar))
-}
diff --git a/contrib/go/_std_1.18/src/crypto/elliptic/p256_asm.go b/contrib/go/_std_1.18/src/crypto/elliptic/p256_asm.go
deleted file mode 100644
index 8624e031a3..0000000000
--- a/contrib/go/_std_1.18/src/crypto/elliptic/p256_asm.go
+++ /dev/null
@@ -1,544 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file contains the Go wrapper for the constant-time, 64-bit assembly
-// implementation of P256. The optimizations performed here are described in
-// detail in:
-// S.Gueron and V.Krasnov, "Fast prime field elliptic-curve cryptography with
-//                          256-bit primes"
-// https://link.springer.com/article/10.1007%2Fs13389-014-0090-x
-// https://eprint.iacr.org/2013/816.pdf
-
-//go:build amd64 || arm64
-
-package elliptic
-
-import (
-	_ "embed"
-	"math/big"
-)
-
-//go:generate go run -tags=tablegen gen_p256_table.go
-
-//go:embed p256_asm_table.bin
-var p256Precomputed string
-
-type (
-	p256Curve struct {
-		*CurveParams
-	}
-
-	p256Point struct {
-		xyz [12]uint64
-	}
-)
-
-var p256 p256Curve
-
-func initP256() {
-	// See FIPS 186-3, section D.2.3
-	p256.CurveParams = &CurveParams{Name: "P-256"}
-	p256.P, _ = new(big.Int).SetString("115792089210356248762697446949407573530086143415290314195533631308867097853951", 10)
-	p256.N, _ = new(big.Int).SetString("115792089210356248762697446949407573529996955224135760342422259061068512044369", 10)
-	p256.B, _ = new(big.Int).SetString("5ac635d8aa3a93e7b3ebbd55769886bc651d06b0cc53b0f63bce3c3e27d2604b", 16)
-	p256.Gx, _ = new(big.Int).SetString("6b17d1f2e12c4247f8bce6e563a440f277037d812deb33a0f4a13945d898c296", 16)
-	p256.Gy, _ = new(big.Int).SetString("4fe342e2fe1a7f9b8ee7eb4a7c0f9e162bce33576b315ececbb6406837bf51f5", 16)
-	p256.BitSize = 256
-}
-
-func (curve p256Curve) Params() *CurveParams {
-	return curve.CurveParams
-}
-
-// Functions implemented in p256_asm_*64.s
-// Montgomery multiplication modulo P256
-//go:noescape
-func p256Mul(res, in1, in2 []uint64)
-
-// Montgomery square modulo P256, repeated n times (n >= 1)
-//go:noescape
-func p256Sqr(res, in []uint64, n int)
-
-// Montgomery multiplication by 1
-//go:noescape
-func p256FromMont(res, in []uint64)
-
-// iff cond == 1  val <- -val
-//go:noescape
-func p256NegCond(val []uint64, cond int)
-
-// if cond == 0 res <- b; else res <- a
-//go:noescape
-func p256MovCond(res, a, b []uint64, cond int)
-
-// Endianness swap
-//go:noescape
-func p256BigToLittle(res []uint64, in []byte)
-
-//go:noescape
-func p256LittleToBig(res []byte, in []uint64)
-
-// Constant time table access
-//go:noescape
-func p256Select(point, table []uint64, idx int)
-
-//go:noescape
-func p256SelectBase(point *[12]uint64, table string, idx int)
-
-// Montgomery multiplication modulo Ord(G)
-//go:noescape
-func p256OrdMul(res, in1, in2 []uint64)
-
-// Montgomery square modulo Ord(G), repeated n times
-//go:noescape
-func p256OrdSqr(res, in []uint64, n int)
-
-// Point add with in2 being affine point
-// If sign == 1 -> in2 = -in2
-// If sel == 0 -> res = in1
-// if zero == 0 -> res = in2
-//go:noescape
-func p256PointAddAffineAsm(res, in1, in2 []uint64, sign, sel, zero int)
-
-// Point add. Returns one if the two input points were equal and zero
-// otherwise. (Note that, due to the way that the equations work out, some
-// representations of ∞ are considered equal to everything by this function.)
-//go:noescape
-func p256PointAddAsm(res, in1, in2 []uint64) int
-
-// Point double
-//go:noescape
-func p256PointDoubleAsm(res, in []uint64)
-
-func (curve p256Curve) Inverse(k *big.Int) *big.Int {
-	if k.Sign() < 0 {
-		// This should never happen.
-		k = new(big.Int).Neg(k)
-	}
-
-	if k.Cmp(p256.N) >= 0 {
-		// This should never happen.
-		k = new(big.Int).Mod(k, p256.N)
-	}
-
-	// table will store precomputed powers of x.
-	var table [4 * 9]uint64
-	var (
-		_1      = table[4*0 : 4*1]
-		_11     = table[4*1 : 4*2]
-		_101    = table[4*2 : 4*3]
-		_111    = table[4*3 : 4*4]
-		_1111   = table[4*4 : 4*5]
-		_10101  = table[4*5 : 4*6]
-		_101111 = table[4*6 : 4*7]
-		x       = table[4*7 : 4*8]
-		t       = table[4*8 : 4*9]
-	)
-
-	fromBig(x[:], k)
-	// This code operates in the Montgomery domain where R = 2^256 mod n
-	// and n is the order of the scalar field. (See initP256 for the
-	// value.) Elements in the Montgomery domain take the form a×R and
-	// multiplication of x and y in the calculates (x × y × R^-1) mod n. RR
-	// is R×R mod n thus the Montgomery multiplication x and RR gives x×R,
-	// i.e. converts x into the Montgomery domain.
-	// Window values borrowed from https://briansmith.org/ecc-inversion-addition-chains-01#p256_scalar_inversion
-	RR := []uint64{0x83244c95be79eea2, 0x4699799c49bd6fa6, 0x2845b2392b6bec59, 0x66e12d94f3d95620}
-	p256OrdMul(_1, x, RR)      // _1
-	p256OrdSqr(x, _1, 1)       // _10
-	p256OrdMul(_11, x, _1)     // _11
-	p256OrdMul(_101, x, _11)   // _101
-	p256OrdMul(_111, x, _101)  // _111
-	p256OrdSqr(x, _101, 1)     // _1010
-	p256OrdMul(_1111, _101, x) // _1111
-
-	p256OrdSqr(t, x, 1)          // _10100
-	p256OrdMul(_10101, t, _1)    // _10101
-	p256OrdSqr(x, _10101, 1)     // _101010
-	p256OrdMul(_101111, _101, x) // _101111
-	p256OrdMul(x, _10101, x)     // _111111 = x6
-	p256OrdSqr(t, x, 2)          // _11111100
-	p256OrdMul(t, t, _11)        // _11111111 = x8
-	p256OrdSqr(x, t, 8)          // _ff00
-	p256OrdMul(x, x, t)          // _ffff = x16
-	p256OrdSqr(t, x, 16)         // _ffff0000
-	p256OrdMul(t, t, x)          // _ffffffff = x32
-
-	p256OrdSqr(x, t, 64)
-	p256OrdMul(x, x, t)
-	p256OrdSqr(x, x, 32)
-	p256OrdMul(x, x, t)
-
-	sqrs := []uint8{
-		6, 5, 4, 5, 5,
-		4, 3, 3, 5, 9,
-		6, 2, 5, 6, 5,
-		4, 5, 5, 3, 10,
-		2, 5, 5, 3, 7, 6}
-	muls := [][]uint64{
-		_101111, _111, _11, _1111, _10101,
-		_101, _101, _101, _111, _101111,
-		_1111, _1, _1, _1111, _111,
-		_111, _111, _101, _11, _101111,
-		_11, _11, _11, _1, _10101, _1111}
-
-	for i, s := range sqrs {
-		p256OrdSqr(x, x, int(s))
-		p256OrdMul(x, x, muls[i])
-	}
-
-	// Multiplying by one in the Montgomery domain converts a Montgomery
-	// value out of the domain.
-	one := []uint64{1, 0, 0, 0}
-	p256OrdMul(x, x, one)
-
-	xOut := make([]byte, 32)
-	p256LittleToBig(xOut, x)
-	return new(big.Int).SetBytes(xOut)
-}
-
-// fromBig converts a *big.Int into a format used by this code.
-func fromBig(out []uint64, big *big.Int) {
-	for i := range out {
-		out[i] = 0
-	}
-
-	for i, v := range big.Bits() {
-		out[i] = uint64(v)
-	}
-}
-
-// p256GetScalar endian-swaps the big-endian scalar value from in and writes it
-// to out. If the scalar is equal or greater than the order of the group, it's
-// reduced modulo that order.
-func p256GetScalar(out []uint64, in []byte) {
-	n := new(big.Int).SetBytes(in)
-
-	if n.Cmp(p256.N) >= 0 {
-		n.Mod(n, p256.N)
-	}
-	fromBig(out, n)
-}
-
-// p256Mul operates in a Montgomery domain with R = 2^256 mod p, where p is the
-// underlying field of the curve. (See initP256 for the value.) Thus rr here is
-// R×R mod p. See comment in Inverse about how this is used.
-var rr = []uint64{0x0000000000000003, 0xfffffffbffffffff, 0xfffffffffffffffe, 0x00000004fffffffd}
-
-func maybeReduceModP(in *big.Int) *big.Int {
-	if in.Cmp(p256.P) < 0 {
-		return in
-	}
-	return new(big.Int).Mod(in, p256.P)
-}
-
-func (curve p256Curve) CombinedMult(bigX, bigY *big.Int, baseScalar, scalar []byte) (x, y *big.Int) {
-	scalarReversed := make([]uint64, 4)
-	var r1, r2 p256Point
-	p256GetScalar(scalarReversed, baseScalar)
-	r1IsInfinity := scalarIsZero(scalarReversed)
-	r1.p256BaseMult(scalarReversed)
-
-	p256GetScalar(scalarReversed, scalar)
-	r2IsInfinity := scalarIsZero(scalarReversed)
-	fromBig(r2.xyz[0:4], maybeReduceModP(bigX))
-	fromBig(r2.xyz[4:8], maybeReduceModP(bigY))
-	p256Mul(r2.xyz[0:4], r2.xyz[0:4], rr[:])
-	p256Mul(r2.xyz[4:8], r2.xyz[4:8], rr[:])
-
-	// This sets r2's Z value to 1, in the Montgomery domain.
-	r2.xyz[8] = 0x0000000000000001
-	r2.xyz[9] = 0xffffffff00000000
-	r2.xyz[10] = 0xffffffffffffffff
-	r2.xyz[11] = 0x00000000fffffffe
-
-	r2.p256ScalarMult(scalarReversed)
-
-	var sum, double p256Point
-	pointsEqual := p256PointAddAsm(sum.xyz[:], r1.xyz[:], r2.xyz[:])
-	p256PointDoubleAsm(double.xyz[:], r1.xyz[:])
-	sum.CopyConditional(&double, pointsEqual)
-	sum.CopyConditional(&r1, r2IsInfinity)
-	sum.CopyConditional(&r2, r1IsInfinity)
-
-	return sum.p256PointToAffine()
-}
-
-func (curve p256Curve) ScalarBaseMult(scalar []byte) (x, y *big.Int) {
-	scalarReversed := make([]uint64, 4)
-	p256GetScalar(scalarReversed, scalar)
-
-	var r p256Point
-	r.p256BaseMult(scalarReversed)
-	return r.p256PointToAffine()
-}
-
-func (curve p256Curve) ScalarMult(bigX, bigY *big.Int, scalar []byte) (x, y *big.Int) {
-	scalarReversed := make([]uint64, 4)
-	p256GetScalar(scalarReversed, scalar)
-
-	var r p256Point
-	fromBig(r.xyz[0:4], maybeReduceModP(bigX))
-	fromBig(r.xyz[4:8], maybeReduceModP(bigY))
-	p256Mul(r.xyz[0:4], r.xyz[0:4], rr[:])
-	p256Mul(r.xyz[4:8], r.xyz[4:8], rr[:])
-	// This sets r2's Z value to 1, in the Montgomery domain.
-	r.xyz[8] = 0x0000000000000001
-	r.xyz[9] = 0xffffffff00000000
-	r.xyz[10] = 0xffffffffffffffff
-	r.xyz[11] = 0x00000000fffffffe
-
-	r.p256ScalarMult(scalarReversed)
-	return r.p256PointToAffine()
-}
-
-// uint64IsZero returns 1 if x is zero and zero otherwise.
-func uint64IsZero(x uint64) int {
-	x = ^x
-	x &= x >> 32
-	x &= x >> 16
-	x &= x >> 8
-	x &= x >> 4
-	x &= x >> 2
-	x &= x >> 1
-	return int(x & 1)
-}
-
-// scalarIsZero returns 1 if scalar represents the zero value, and zero
-// otherwise.
-func scalarIsZero(scalar []uint64) int {
-	return uint64IsZero(scalar[0] | scalar[1] | scalar[2] | scalar[3])
-}
-
-func (p *p256Point) p256PointToAffine() (x, y *big.Int) {
-	zInv := make([]uint64, 4)
-	zInvSq := make([]uint64, 4)
-	p256Inverse(zInv, p.xyz[8:12])
-	p256Sqr(zInvSq, zInv, 1)
-	p256Mul(zInv, zInv, zInvSq)
-
-	p256Mul(zInvSq, p.xyz[0:4], zInvSq)
-	p256Mul(zInv, p.xyz[4:8], zInv)
-
-	p256FromMont(zInvSq, zInvSq)
-	p256FromMont(zInv, zInv)
-
-	xOut := make([]byte, 32)
-	yOut := make([]byte, 32)
-	p256LittleToBig(xOut, zInvSq)
-	p256LittleToBig(yOut, zInv)
-
-	return new(big.Int).SetBytes(xOut), new(big.Int).SetBytes(yOut)
-}
-
-// CopyConditional copies overwrites p with src if v == 1, and leaves p
-// unchanged if v == 0.
-func (p *p256Point) CopyConditional(src *p256Point, v int) {
-	pMask := uint64(v) - 1
-	srcMask := ^pMask
-
-	for i, n := range p.xyz {
-		p.xyz[i] = (n & pMask) | (src.xyz[i] & srcMask)
-	}
-}
-
-// p256Inverse sets out to in^-1 mod p.
-func p256Inverse(out, in []uint64) {
-	var stack [6 * 4]uint64
-	p2 := stack[4*0 : 4*0+4]
-	p4 := stack[4*1 : 4*1+4]
-	p8 := stack[4*2 : 4*2+4]
-	p16 := stack[4*3 : 4*3+4]
-	p32 := stack[4*4 : 4*4+4]
-
-	p256Sqr(out, in, 1)
-	p256Mul(p2, out, in) // 3*p
-
-	p256Sqr(out, p2, 2)
-	p256Mul(p4, out, p2) // f*p
-
-	p256Sqr(out, p4, 4)
-	p256Mul(p8, out, p4) // ff*p
-
-	p256Sqr(out, p8, 8)
-	p256Mul(p16, out, p8) // ffff*p
-
-	p256Sqr(out, p16, 16)
-	p256Mul(p32, out, p16) // ffffffff*p
-
-	p256Sqr(out, p32, 32)
-	p256Mul(out, out, in)
-
-	p256Sqr(out, out, 128)
-	p256Mul(out, out, p32)
-
-	p256Sqr(out, out, 32)
-	p256Mul(out, out, p32)
-
-	p256Sqr(out, out, 16)
-	p256Mul(out, out, p16)
-
-	p256Sqr(out, out, 8)
-	p256Mul(out, out, p8)
-
-	p256Sqr(out, out, 4)
-	p256Mul(out, out, p4)
-
-	p256Sqr(out, out, 2)
-	p256Mul(out, out, p2)
-
-	p256Sqr(out, out, 2)
-	p256Mul(out, out, in)
-}
-
-func (p *p256Point) p256StorePoint(r *[16 * 4 * 3]uint64, index int) {
-	copy(r[index*12:], p.xyz[:])
-}
-
-func boothW5(in uint) (int, int) {
-	var s uint = ^((in >> 5) - 1)
-	var d uint = (1 << 6) - in - 1
-	d = (d & s) | (in & (^s))
-	d = (d >> 1) + (d & 1)
-	return int(d), int(s & 1)
-}
-
-func boothW6(in uint) (int, int) {
-	var s uint = ^((in >> 6) - 1)
-	var d uint = (1 << 7) - in - 1
-	d = (d & s) | (in & (^s))
-	d = (d >> 1) + (d & 1)
-	return int(d), int(s & 1)
-}
-
-func (p *p256Point) p256BaseMult(scalar []uint64) {
-	wvalue := (scalar[0] << 1) & 0x7f
-	sel, sign := boothW6(uint(wvalue))
-	p256SelectBase(&p.xyz, p256Precomputed, sel)
-	p256NegCond(p.xyz[4:8], sign)
-
-	// (This is one, in the Montgomery domain.)
-	p.xyz[8] = 0x0000000000000001
-	p.xyz[9] = 0xffffffff00000000
-	p.xyz[10] = 0xffffffffffffffff
-	p.xyz[11] = 0x00000000fffffffe
-
-	var t0 p256Point
-	// (This is one, in the Montgomery domain.)
-	t0.xyz[8] = 0x0000000000000001
-	t0.xyz[9] = 0xffffffff00000000
-	t0.xyz[10] = 0xffffffffffffffff
-	t0.xyz[11] = 0x00000000fffffffe
-
-	index := uint(5)
-	zero := sel
-
-	for i := 1; i < 43; i++ {
-		if index < 192 {
-			wvalue = ((scalar[index/64] >> (index % 64)) + (scalar[index/64+1] << (64 - (index % 64)))) & 0x7f
-		} else {
-			wvalue = (scalar[index/64] >> (index % 64)) & 0x7f
-		}
-		index += 6
-		sel, sign = boothW6(uint(wvalue))
-		p256SelectBase(&t0.xyz, p256Precomputed[i*32*8*8:], sel)
-		p256PointAddAffineAsm(p.xyz[0:12], p.xyz[0:12], t0.xyz[0:8], sign, sel, zero)
-		zero |= sel
-	}
-}
-
-func (p *p256Point) p256ScalarMult(scalar []uint64) {
-	// precomp is a table of precomputed points that stores powers of p
-	// from p^1 to p^16.
-	var precomp [16 * 4 * 3]uint64
-	var t0, t1, t2, t3 p256Point
-
-	// Prepare the table
-	p.p256StorePoint(&precomp, 0) // 1
-
-	p256PointDoubleAsm(t0.xyz[:], p.xyz[:])
-	p256PointDoubleAsm(t1.xyz[:], t0.xyz[:])
-	p256PointDoubleAsm(t2.xyz[:], t1.xyz[:])
-	p256PointDoubleAsm(t3.xyz[:], t2.xyz[:])
-	t0.p256StorePoint(&precomp, 1)  // 2
-	t1.p256StorePoint(&precomp, 3)  // 4
-	t2.p256StorePoint(&precomp, 7)  // 8
-	t3.p256StorePoint(&precomp, 15) // 16
-
-	p256PointAddAsm(t0.xyz[:], t0.xyz[:], p.xyz[:])
-	p256PointAddAsm(t1.xyz[:], t1.xyz[:], p.xyz[:])
-	p256PointAddAsm(t2.xyz[:], t2.xyz[:], p.xyz[:])
-	t0.p256StorePoint(&precomp, 2) // 3
-	t1.p256StorePoint(&precomp, 4) // 5
-	t2.p256StorePoint(&precomp, 8) // 9
-
-	p256PointDoubleAsm(t0.xyz[:], t0.xyz[:])
-	p256PointDoubleAsm(t1.xyz[:], t1.xyz[:])
-	t0.p256StorePoint(&precomp, 5) // 6
-	t1.p256StorePoint(&precomp, 9) // 10
-
-	p256PointAddAsm(t2.xyz[:], t0.xyz[:], p.xyz[:])
-	p256PointAddAsm(t1.xyz[:], t1.xyz[:], p.xyz[:])
-	t2.p256StorePoint(&precomp, 6)  // 7
-	t1.p256StorePoint(&precomp, 10) // 11
-
-	p256PointDoubleAsm(t0.xyz[:], t0.xyz[:])
-	p256PointDoubleAsm(t2.xyz[:], t2.xyz[:])
-	t0.p256StorePoint(&precomp, 11) // 12
-	t2.p256StorePoint(&precomp, 13) // 14
-
-	p256PointAddAsm(t0.xyz[:], t0.xyz[:], p.xyz[:])
-	p256PointAddAsm(t2.xyz[:], t2.xyz[:], p.xyz[:])
-	t0.p256StorePoint(&precomp, 12) // 13
-	t2.p256StorePoint(&precomp, 14) // 15
-
-	// Start scanning the window from top bit
-	index := uint(254)
-	var sel, sign int
-
-	wvalue := (scalar[index/64] >> (index % 64)) & 0x3f
-	sel, _ = boothW5(uint(wvalue))
-
-	p256Select(p.xyz[0:12], precomp[0:], sel)
-	zero := sel
-
-	for index > 4 {
-		index -= 5
-		p256PointDoubleAsm(p.xyz[:], p.xyz[:])
-		p256PointDoubleAsm(p.xyz[:], p.xyz[:])
-		p256PointDoubleAsm(p.xyz[:], p.xyz[:])
-		p256PointDoubleAsm(p.xyz[:], p.xyz[:])
-		p256PointDoubleAsm(p.xyz[:], p.xyz[:])
-
-		if index < 192 {
-			wvalue = ((scalar[index/64] >> (index % 64)) + (scalar[index/64+1] << (64 - (index % 64)))) & 0x3f
-		} else {
-			wvalue = (scalar[index/64] >> (index % 64)) & 0x3f
-		}
-
-		sel, sign = boothW5(uint(wvalue))
-
-		p256Select(t0.xyz[0:], precomp[0:], sel)
-		p256NegCond(t0.xyz[4:8], sign)
-		p256PointAddAsm(t1.xyz[:], p.xyz[:], t0.xyz[:])
-		p256MovCond(t1.xyz[0:12], t1.xyz[0:12], p.xyz[0:12], sel)
-		p256MovCond(p.xyz[0:12], t1.xyz[0:12], t0.xyz[0:12], zero)
-		zero |= sel
-	}
-
-	p256PointDoubleAsm(p.xyz[:], p.xyz[:])
-	p256PointDoubleAsm(p.xyz[:], p.xyz[:])
-	p256PointDoubleAsm(p.xyz[:], p.xyz[:])
-	p256PointDoubleAsm(p.xyz[:], p.xyz[:])
-	p256PointDoubleAsm(p.xyz[:], p.xyz[:])
-
-	wvalue = (scalar[0] << 1) & 0x3f
-	sel, sign = boothW5(uint(wvalue))
-
-	p256Select(t0.xyz[0:], precomp[0:], sel)
-	p256NegCond(t0.xyz[4:8], sign)
-	p256PointAddAsm(t1.xyz[:], p.xyz[:], t0.xyz[:])
-	p256MovCond(t1.xyz[0:12], t1.xyz[0:12], p.xyz[0:12], sel)
-	p256MovCond(p.xyz[0:12], t1.xyz[0:12], t0.xyz[0:12], zero)
-}
diff --git a/contrib/go/_std_1.18/src/crypto/elliptic/p256_asm_amd64.s b/contrib/go/_std_1.18/src/crypto/elliptic/p256_asm_amd64.s
deleted file mode 100644
index bd16add241..0000000000
--- a/contrib/go/_std_1.18/src/crypto/elliptic/p256_asm_amd64.s
+++ /dev/null
@@ -1,2347 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file contains constant-time, 64-bit assembly implementation of
-// P256. The optimizations performed here are described in detail in:
-// S.Gueron and V.Krasnov, "Fast prime field elliptic-curve cryptography with
-//                          256-bit primes"
-// https://link.springer.com/article/10.1007%2Fs13389-014-0090-x
-// https://eprint.iacr.org/2013/816.pdf
-
-#include "textflag.h"
-
-#define res_ptr DI
-#define x_ptr SI
-#define y_ptr CX
-
-#define acc0 R8
-#define acc1 R9
-#define acc2 R10
-#define acc3 R11
-#define acc4 R12
-#define acc5 R13
-#define t0 R14
-#define t1 R15
-
-DATA p256const0<>+0x00(SB)/8, $0x00000000ffffffff
-DATA p256const1<>+0x00(SB)/8, $0xffffffff00000001
-DATA p256ordK0<>+0x00(SB)/8, $0xccd1c8aaee00bc4f
-DATA p256ord<>+0x00(SB)/8, $0xf3b9cac2fc632551
-DATA p256ord<>+0x08(SB)/8, $0xbce6faada7179e84
-DATA p256ord<>+0x10(SB)/8, $0xffffffffffffffff
-DATA p256ord<>+0x18(SB)/8, $0xffffffff00000000
-DATA p256one<>+0x00(SB)/8, $0x0000000000000001
-DATA p256one<>+0x08(SB)/8, $0xffffffff00000000
-DATA p256one<>+0x10(SB)/8, $0xffffffffffffffff
-DATA p256one<>+0x18(SB)/8, $0x00000000fffffffe
-GLOBL p256const0<>(SB), 8, $8
-GLOBL p256const1<>(SB), 8, $8
-GLOBL p256ordK0<>(SB), 8, $8
-GLOBL p256ord<>(SB), 8, $32
-GLOBL p256one<>(SB), 8, $32
-
-/* ---------------------------------------*/
-// func p256LittleToBig(res []byte, in []uint64)
-TEXT ·p256LittleToBig(SB),NOSPLIT,$0
-	JMP ·p256BigToLittle(SB)
-/* ---------------------------------------*/
-// func p256BigToLittle(res []uint64, in []byte)
-TEXT ·p256BigToLittle(SB),NOSPLIT,$0
-	MOVQ res+0(FP), res_ptr
-	MOVQ in+24(FP), x_ptr
-
-	MOVQ (8*0)(x_ptr), acc0
-	MOVQ (8*1)(x_ptr), acc1
-	MOVQ (8*2)(x_ptr), acc2
-	MOVQ (8*3)(x_ptr), acc3
-
-	BSWAPQ acc0
-	BSWAPQ acc1
-	BSWAPQ acc2
-	BSWAPQ acc3
-
-	MOVQ acc3, (8*0)(res_ptr)
-	MOVQ acc2, (8*1)(res_ptr)
-	MOVQ acc1, (8*2)(res_ptr)
-	MOVQ acc0, (8*3)(res_ptr)
-
-	RET
-/* ---------------------------------------*/
-// func p256MovCond(res, a, b []uint64, cond int)
-// If cond == 0 res=b, else res=a
-TEXT ·p256MovCond(SB),NOSPLIT,$0
-	MOVQ res+0(FP), res_ptr
-	MOVQ a+24(FP), x_ptr
-	MOVQ b+48(FP), y_ptr
-	MOVQ cond+72(FP), X12
-
-	PXOR X13, X13
-	PSHUFD $0, X12, X12
-	PCMPEQL X13, X12
-
-	MOVOU X12, X0
-	MOVOU (16*0)(x_ptr), X6
-	PANDN X6, X0
-	MOVOU X12, X1
-	MOVOU (16*1)(x_ptr), X7
-	PANDN X7, X1
-	MOVOU X12, X2
-	MOVOU (16*2)(x_ptr), X8
-	PANDN X8, X2
-	MOVOU X12, X3
-	MOVOU (16*3)(x_ptr), X9
-	PANDN X9, X3
-	MOVOU X12, X4
-	MOVOU (16*4)(x_ptr), X10
-	PANDN X10, X4
-	MOVOU X12, X5
-	MOVOU (16*5)(x_ptr), X11
-	PANDN X11, X5
-
-	MOVOU (16*0)(y_ptr), X6
-	MOVOU (16*1)(y_ptr), X7
-	MOVOU (16*2)(y_ptr), X8
-	MOVOU (16*3)(y_ptr), X9
-	MOVOU (16*4)(y_ptr), X10
-	MOVOU (16*5)(y_ptr), X11
-
-	PAND X12, X6
-	PAND X12, X7
-	PAND X12, X8
-	PAND X12, X9
-	PAND X12, X10
-	PAND X12, X11
-
-	PXOR X6, X0
-	PXOR X7, X1
-	PXOR X8, X2
-	PXOR X9, X3
-	PXOR X10, X4
-	PXOR X11, X5
-
-	MOVOU X0, (16*0)(res_ptr)
-	MOVOU X1, (16*1)(res_ptr)
-	MOVOU X2, (16*2)(res_ptr)
-	MOVOU X3, (16*3)(res_ptr)
-	MOVOU X4, (16*4)(res_ptr)
-	MOVOU X5, (16*5)(res_ptr)
-
-	RET
-/* ---------------------------------------*/
-// func p256NegCond(val []uint64, cond int)
-TEXT ·p256NegCond(SB),NOSPLIT,$0
-	MOVQ val+0(FP), res_ptr
-	MOVQ cond+24(FP), t0
-	// acc = poly
-	MOVQ $-1, acc0
-	MOVQ p256const0<>(SB), acc1
-	MOVQ $0, acc2
-	MOVQ p256const1<>(SB), acc3
-	// Load the original value
-	MOVQ (8*0)(res_ptr), acc5
-	MOVQ (8*1)(res_ptr), x_ptr
-	MOVQ (8*2)(res_ptr), y_ptr
-	MOVQ (8*3)(res_ptr), t1
-	// Speculatively subtract
-	SUBQ acc5, acc0
-	SBBQ x_ptr, acc1
-	SBBQ y_ptr, acc2
-	SBBQ t1, acc3
-	// If condition is 0, keep original value
-	TESTQ t0, t0
-	CMOVQEQ acc5, acc0
-	CMOVQEQ x_ptr, acc1
-	CMOVQEQ y_ptr, acc2
-	CMOVQEQ t1, acc3
-	// Store result
-	MOVQ acc0, (8*0)(res_ptr)
-	MOVQ acc1, (8*1)(res_ptr)
-	MOVQ acc2, (8*2)(res_ptr)
-	MOVQ acc3, (8*3)(res_ptr)
-
-	RET
-/* ---------------------------------------*/
-// func p256Sqr(res, in []uint64, n int)
-TEXT ·p256Sqr(SB),NOSPLIT,$0
-	MOVQ res+0(FP), res_ptr
-	MOVQ in+24(FP), x_ptr
-	MOVQ n+48(FP), BX
-
-sqrLoop:
-
-	// y[1:] * y[0]
-	MOVQ (8*0)(x_ptr), t0
-
-	MOVQ (8*1)(x_ptr), AX
-	MULQ t0
-	MOVQ AX, acc1
-	MOVQ DX, acc2
-
-	MOVQ (8*2)(x_ptr), AX
-	MULQ t0
-	ADDQ AX, acc2
-	ADCQ $0, DX
-	MOVQ DX, acc3
-
-	MOVQ (8*3)(x_ptr), AX
-	MULQ t0
-	ADDQ AX, acc3
-	ADCQ $0, DX
-	MOVQ DX, acc4
-	// y[2:] * y[1]
-	MOVQ (8*1)(x_ptr), t0
-
-	MOVQ (8*2)(x_ptr), AX
-	MULQ t0
-	ADDQ AX, acc3
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ (8*3)(x_ptr), AX
-	MULQ t0
-	ADDQ t1, acc4
-	ADCQ $0, DX
-	ADDQ AX, acc4
-	ADCQ $0, DX
-	MOVQ DX, acc5
-	// y[3] * y[2]
-	MOVQ (8*2)(x_ptr), t0
-
-	MOVQ (8*3)(x_ptr), AX
-	MULQ t0
-	ADDQ AX, acc5
-	ADCQ $0, DX
-	MOVQ DX, y_ptr
-	XORQ t1, t1
-	// *2
-	ADDQ acc1, acc1
-	ADCQ acc2, acc2
-	ADCQ acc3, acc3
-	ADCQ acc4, acc4
-	ADCQ acc5, acc5
-	ADCQ y_ptr, y_ptr
-	ADCQ $0, t1
-	// Missing products
-	MOVQ (8*0)(x_ptr), AX
-	MULQ AX
-	MOVQ AX, acc0
-	MOVQ DX, t0
-
-	MOVQ (8*1)(x_ptr), AX
-	MULQ AX
-	ADDQ t0, acc1
-	ADCQ AX, acc2
-	ADCQ $0, DX
-	MOVQ DX, t0
-
-	MOVQ (8*2)(x_ptr), AX
-	MULQ AX
-	ADDQ t0, acc3
-	ADCQ AX, acc4
-	ADCQ $0, DX
-	MOVQ DX, t0
-
-	MOVQ (8*3)(x_ptr), AX
-	MULQ AX
-	ADDQ t0, acc5
-	ADCQ AX, y_ptr
-	ADCQ DX, t1
-	MOVQ t1, x_ptr
-	// First reduction step
-	MOVQ acc0, AX
-	MOVQ acc0, t1
-	SHLQ $32, acc0
-	MULQ p256const1<>(SB)
-	SHRQ $32, t1
-	ADDQ acc0, acc1
-	ADCQ t1, acc2
-	ADCQ AX, acc3
-	ADCQ $0, DX
-	MOVQ DX, acc0
-	// Second reduction step
-	MOVQ acc1, AX
-	MOVQ acc1, t1
-	SHLQ $32, acc1
-	MULQ p256const1<>(SB)
-	SHRQ $32, t1
-	ADDQ acc1, acc2
-	ADCQ t1, acc3
-	ADCQ AX, acc0
-	ADCQ $0, DX
-	MOVQ DX, acc1
-	// Third reduction step
-	MOVQ acc2, AX
-	MOVQ acc2, t1
-	SHLQ $32, acc2
-	MULQ p256const1<>(SB)
-	SHRQ $32, t1
-	ADDQ acc2, acc3
-	ADCQ t1, acc0
-	ADCQ AX, acc1
-	ADCQ $0, DX
-	MOVQ DX, acc2
-	// Last reduction step
-	XORQ t0, t0
-	MOVQ acc3, AX
-	MOVQ acc3, t1
-	SHLQ $32, acc3
-	MULQ p256const1<>(SB)
-	SHRQ $32, t1
-	ADDQ acc3, acc0
-	ADCQ t1, acc1
-	ADCQ AX, acc2
-	ADCQ $0, DX
-	MOVQ DX, acc3
-	// Add bits [511:256] of the sqr result
-	ADCQ acc4, acc0
-	ADCQ acc5, acc1
-	ADCQ y_ptr, acc2
-	ADCQ x_ptr, acc3
-	ADCQ $0, t0
-
-	MOVQ acc0, acc4
-	MOVQ acc1, acc5
-	MOVQ acc2, y_ptr
-	MOVQ acc3, t1
-	// Subtract p256
-	SUBQ $-1, acc0
-	SBBQ p256const0<>(SB) ,acc1
-	SBBQ $0, acc2
-	SBBQ p256const1<>(SB), acc3
-	SBBQ $0, t0
-
-	CMOVQCS acc4, acc0
-	CMOVQCS acc5, acc1
-	CMOVQCS y_ptr, acc2
-	CMOVQCS t1, acc3
-
-	MOVQ acc0, (8*0)(res_ptr)
-	MOVQ acc1, (8*1)(res_ptr)
-	MOVQ acc2, (8*2)(res_ptr)
-	MOVQ acc3, (8*3)(res_ptr)
-	MOVQ res_ptr, x_ptr
-	DECQ BX
-	JNE  sqrLoop
-
-	RET
-/* ---------------------------------------*/
-// func p256Mul(res, in1, in2 []uint64)
-TEXT ·p256Mul(SB),NOSPLIT,$0
-	MOVQ res+0(FP), res_ptr
-	MOVQ in1+24(FP), x_ptr
-	MOVQ in2+48(FP), y_ptr
-	// x * y[0]
-	MOVQ (8*0)(y_ptr), t0
-
-	MOVQ (8*0)(x_ptr), AX
-	MULQ t0
-	MOVQ AX, acc0
-	MOVQ DX, acc1
-
-	MOVQ (8*1)(x_ptr), AX
-	MULQ t0
-	ADDQ AX, acc1
-	ADCQ $0, DX
-	MOVQ DX, acc2
-
-	MOVQ (8*2)(x_ptr), AX
-	MULQ t0
-	ADDQ AX, acc2
-	ADCQ $0, DX
-	MOVQ DX, acc3
-
-	MOVQ (8*3)(x_ptr), AX
-	MULQ t0
-	ADDQ AX, acc3
-	ADCQ $0, DX
-	MOVQ DX, acc4
-	XORQ acc5, acc5
-	// First reduction step
-	MOVQ acc0, AX
-	MOVQ acc0, t1
-	SHLQ $32, acc0
-	MULQ p256const1<>(SB)
-	SHRQ $32, t1
-	ADDQ acc0, acc1
-	ADCQ t1, acc2
-	ADCQ AX, acc3
-	ADCQ DX, acc4
-	ADCQ $0, acc5
-	XORQ acc0, acc0
-	// x * y[1]
-	MOVQ (8*1)(y_ptr), t0
-
-	MOVQ (8*0)(x_ptr), AX
-	MULQ t0
-	ADDQ AX, acc1
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ (8*1)(x_ptr), AX
-	MULQ t0
-	ADDQ t1, acc2
-	ADCQ $0, DX
-	ADDQ AX, acc2
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ (8*2)(x_ptr), AX
-	MULQ t0
-	ADDQ t1, acc3
-	ADCQ $0, DX
-	ADDQ AX, acc3
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ (8*3)(x_ptr), AX
-	MULQ t0
-	ADDQ t1, acc4
-	ADCQ $0, DX
-	ADDQ AX, acc4
-	ADCQ DX, acc5
-	ADCQ $0, acc0
-	// Second reduction step
-	MOVQ acc1, AX
-	MOVQ acc1, t1
-	SHLQ $32, acc1
-	MULQ p256const1<>(SB)
-	SHRQ $32, t1
-	ADDQ acc1, acc2
-	ADCQ t1, acc3
-	ADCQ AX, acc4
-	ADCQ DX, acc5
-	ADCQ $0, acc0
-	XORQ acc1, acc1
-	// x * y[2]
-	MOVQ (8*2)(y_ptr), t0
-
-	MOVQ (8*0)(x_ptr), AX
-	MULQ t0
-	ADDQ AX, acc2
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ (8*1)(x_ptr), AX
-	MULQ t0
-	ADDQ t1, acc3
-	ADCQ $0, DX
-	ADDQ AX, acc3
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ (8*2)(x_ptr), AX
-	MULQ t0
-	ADDQ t1, acc4
-	ADCQ $0, DX
-	ADDQ AX, acc4
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ (8*3)(x_ptr), AX
-	MULQ t0
-	ADDQ t1, acc5
-	ADCQ $0, DX
-	ADDQ AX, acc5
-	ADCQ DX, acc0
-	ADCQ $0, acc1
-	// Third reduction step
-	MOVQ acc2, AX
-	MOVQ acc2, t1
-	SHLQ $32, acc2
-	MULQ p256const1<>(SB)
-	SHRQ $32, t1
-	ADDQ acc2, acc3
-	ADCQ t1, acc4
-	ADCQ AX, acc5
-	ADCQ DX, acc0
-	ADCQ $0, acc1
-	XORQ acc2, acc2
-	// x * y[3]
-	MOVQ (8*3)(y_ptr), t0
-
-	MOVQ (8*0)(x_ptr), AX
-	MULQ t0
-	ADDQ AX, acc3
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ (8*1)(x_ptr), AX
-	MULQ t0
-	ADDQ t1, acc4
-	ADCQ $0, DX
-	ADDQ AX, acc4
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ (8*2)(x_ptr), AX
-	MULQ t0
-	ADDQ t1, acc5
-	ADCQ $0, DX
-	ADDQ AX, acc5
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ (8*3)(x_ptr), AX
-	MULQ t0
-	ADDQ t1, acc0
-	ADCQ $0, DX
-	ADDQ AX, acc0
-	ADCQ DX, acc1
-	ADCQ $0, acc2
-	// Last reduction step
-	MOVQ acc3, AX
-	MOVQ acc3, t1
-	SHLQ $32, acc3
-	MULQ p256const1<>(SB)
-	SHRQ $32, t1
-	ADDQ acc3, acc4
-	ADCQ t1, acc5
-	ADCQ AX, acc0
-	ADCQ DX, acc1
-	ADCQ $0, acc2
-	// Copy result [255:0]
-	MOVQ acc4, x_ptr
-	MOVQ acc5, acc3
-	MOVQ acc0, t0
-	MOVQ acc1, t1
-	// Subtract p256
-	SUBQ $-1, acc4
-	SBBQ p256const0<>(SB) ,acc5
-	SBBQ $0, acc0
-	SBBQ p256const1<>(SB), acc1
-	SBBQ $0, acc2
-
-	CMOVQCS x_ptr, acc4
-	CMOVQCS acc3, acc5
-	CMOVQCS t0, acc0
-	CMOVQCS t1, acc1
-
-	MOVQ acc4, (8*0)(res_ptr)
-	MOVQ acc5, (8*1)(res_ptr)
-	MOVQ acc0, (8*2)(res_ptr)
-	MOVQ acc1, (8*3)(res_ptr)
-
-	RET
-/* ---------------------------------------*/
-// func p256FromMont(res, in []uint64)
-TEXT ·p256FromMont(SB),NOSPLIT,$0
-	MOVQ res+0(FP), res_ptr
-	MOVQ in+24(FP), x_ptr
-
-	MOVQ (8*0)(x_ptr), acc0
-	MOVQ (8*1)(x_ptr), acc1
-	MOVQ (8*2)(x_ptr), acc2
-	MOVQ (8*3)(x_ptr), acc3
-	XORQ acc4, acc4
-
-	// Only reduce, no multiplications are needed
-	// First stage
-	MOVQ acc0, AX
-	MOVQ acc0, t1
-	SHLQ $32, acc0
-	MULQ p256const1<>(SB)
-	SHRQ $32, t1
-	ADDQ acc0, acc1
-	ADCQ t1, acc2
-	ADCQ AX, acc3
-	ADCQ DX, acc4
-	XORQ acc5, acc5
-	// Second stage
-	MOVQ acc1, AX
-	MOVQ acc1, t1
-	SHLQ $32, acc1
-	MULQ p256const1<>(SB)
-	SHRQ $32, t1
-	ADDQ acc1, acc2
-	ADCQ t1, acc3
-	ADCQ AX, acc4
-	ADCQ DX, acc5
-	XORQ acc0, acc0
-	// Third stage
-	MOVQ acc2, AX
-	MOVQ acc2, t1
-	SHLQ $32, acc2
-	MULQ p256const1<>(SB)
-	SHRQ $32, t1
-	ADDQ acc2, acc3
-	ADCQ t1, acc4
-	ADCQ AX, acc5
-	ADCQ DX, acc0
-	XORQ acc1, acc1
-	// Last stage
-	MOVQ acc3, AX
-	MOVQ acc3, t1
-	SHLQ $32, acc3
-	MULQ p256const1<>(SB)
-	SHRQ $32, t1
-	ADDQ acc3, acc4
-	ADCQ t1, acc5
-	ADCQ AX, acc0
-	ADCQ DX, acc1
-
-	MOVQ acc4, x_ptr
-	MOVQ acc5, acc3
-	MOVQ acc0, t0
-	MOVQ acc1, t1
-
-	SUBQ $-1, acc4
-	SBBQ p256const0<>(SB), acc5
-	SBBQ $0, acc0
-	SBBQ p256const1<>(SB), acc1
-
-	CMOVQCS x_ptr, acc4
-	CMOVQCS acc3, acc5
-	CMOVQCS t0, acc0
-	CMOVQCS t1, acc1
-
-	MOVQ acc4, (8*0)(res_ptr)
-	MOVQ acc5, (8*1)(res_ptr)
-	MOVQ acc0, (8*2)(res_ptr)
-	MOVQ acc1, (8*3)(res_ptr)
-
-	RET
-/* ---------------------------------------*/
-// Constant time point access to arbitrary point table.
-// Indexed from 1 to 15, with -1 offset
-// (index 0 is implicitly point at infinity)
-// func p256Select(point, table []uint64, idx int)
-TEXT ·p256Select(SB),NOSPLIT,$0
-	MOVQ idx+48(FP),AX
-	MOVQ table+24(FP),DI
-	MOVQ point+0(FP),DX
-
-	PXOR X15, X15	// X15 = 0
-	PCMPEQL X14, X14 // X14 = -1
-	PSUBL X14, X15   // X15 = 1
-	MOVL AX, X14
-	PSHUFD $0, X14, X14
-
-	PXOR X0, X0
-	PXOR X1, X1
-	PXOR X2, X2
-	PXOR X3, X3
-	PXOR X4, X4
-	PXOR X5, X5
-	MOVQ $16, AX
-
-	MOVOU X15, X13
-
-loop_select:
-
-		MOVOU X13, X12
-		PADDL X15, X13
-		PCMPEQL X14, X12
-
-		MOVOU (16*0)(DI), X6
-		MOVOU (16*1)(DI), X7
-		MOVOU (16*2)(DI), X8
-		MOVOU (16*3)(DI), X9
-		MOVOU (16*4)(DI), X10
-		MOVOU (16*5)(DI), X11
-		ADDQ $(16*6), DI
-
-		PAND X12, X6
-		PAND X12, X7
-		PAND X12, X8
-		PAND X12, X9
-		PAND X12, X10
-		PAND X12, X11
-
-		PXOR X6, X0
-		PXOR X7, X1
-		PXOR X8, X2
-		PXOR X9, X3
-		PXOR X10, X4
-		PXOR X11, X5
-
-		DECQ AX
-		JNE loop_select
-
-	MOVOU X0, (16*0)(DX)
-	MOVOU X1, (16*1)(DX)
-	MOVOU X2, (16*2)(DX)
-	MOVOU X3, (16*3)(DX)
-	MOVOU X4, (16*4)(DX)
-	MOVOU X5, (16*5)(DX)
-
-	RET
-/* ---------------------------------------*/
-// Constant time point access to base point table.
-// func p256SelectBase(point *[12]uint64, table string, idx int)
-TEXT ·p256SelectBase(SB),NOSPLIT,$0
-	MOVQ idx+24(FP),AX
-	MOVQ table+8(FP),DI
-	MOVQ point+0(FP),DX
-
-	PXOR X15, X15	// X15 = 0
-	PCMPEQL X14, X14 // X14 = -1
-	PSUBL X14, X15   // X15 = 1
-	MOVL AX, X14
-	PSHUFD $0, X14, X14
-
-	PXOR X0, X0
-	PXOR X1, X1
-	PXOR X2, X2
-	PXOR X3, X3
-	MOVQ $16, AX
-
-	MOVOU X15, X13
-
-loop_select_base:
-
-		MOVOU X13, X12
-		PADDL X15, X13
-		PCMPEQL X14, X12
-
-		MOVOU (16*0)(DI), X4
-		MOVOU (16*1)(DI), X5
-		MOVOU (16*2)(DI), X6
-		MOVOU (16*3)(DI), X7
-
-		MOVOU (16*4)(DI), X8
-		MOVOU (16*5)(DI), X9
-		MOVOU (16*6)(DI), X10
-		MOVOU (16*7)(DI), X11
-
-		ADDQ $(16*8), DI
-
-		PAND X12, X4
-		PAND X12, X5
-		PAND X12, X6
-		PAND X12, X7
-
-		MOVOU X13, X12
-		PADDL X15, X13
-		PCMPEQL X14, X12
-
-		PAND X12, X8
-		PAND X12, X9
-		PAND X12, X10
-		PAND X12, X11
-
-		PXOR X4, X0
-		PXOR X5, X1
-		PXOR X6, X2
-		PXOR X7, X3
-
-		PXOR X8, X0
-		PXOR X9, X1
-		PXOR X10, X2
-		PXOR X11, X3
-
-		DECQ AX
-		JNE loop_select_base
-
-	MOVOU X0, (16*0)(DX)
-	MOVOU X1, (16*1)(DX)
-	MOVOU X2, (16*2)(DX)
-	MOVOU X3, (16*3)(DX)
-
-	RET
-/* ---------------------------------------*/
-// func p256OrdMul(res, in1, in2 []uint64)
-TEXT ·p256OrdMul(SB),NOSPLIT,$0
-	MOVQ res+0(FP), res_ptr
-	MOVQ in1+24(FP), x_ptr
-	MOVQ in2+48(FP), y_ptr
-	// x * y[0]
-	MOVQ (8*0)(y_ptr), t0
-
-	MOVQ (8*0)(x_ptr), AX
-	MULQ t0
-	MOVQ AX, acc0
-	MOVQ DX, acc1
-
-	MOVQ (8*1)(x_ptr), AX
-	MULQ t0
-	ADDQ AX, acc1
-	ADCQ $0, DX
-	MOVQ DX, acc2
-
-	MOVQ (8*2)(x_ptr), AX
-	MULQ t0
-	ADDQ AX, acc2
-	ADCQ $0, DX
-	MOVQ DX, acc3
-
-	MOVQ (8*3)(x_ptr), AX
-	MULQ t0
-	ADDQ AX, acc3
-	ADCQ $0, DX
-	MOVQ DX, acc4
-	XORQ acc5, acc5
-	// First reduction step
-	MOVQ acc0, AX
-	MULQ p256ordK0<>(SB)
-	MOVQ AX, t0
-
-	MOVQ p256ord<>+0x00(SB), AX
-	MULQ t0
-	ADDQ AX, acc0
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ p256ord<>+0x08(SB), AX
-	MULQ t0
-	ADDQ t1, acc1
-	ADCQ $0, DX
-	ADDQ AX, acc1
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ p256ord<>+0x10(SB), AX
-	MULQ t0
-	ADDQ t1, acc2
-	ADCQ $0, DX
-	ADDQ AX, acc2
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ p256ord<>+0x18(SB), AX
-	MULQ t0
-	ADDQ t1, acc3
-	ADCQ $0, DX
-	ADDQ AX, acc3
-	ADCQ DX, acc4
-	ADCQ $0, acc5
-	// x * y[1]
-	MOVQ (8*1)(y_ptr), t0
-
-	MOVQ (8*0)(x_ptr), AX
-	MULQ t0
-	ADDQ AX, acc1
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ (8*1)(x_ptr), AX
-	MULQ t0
-	ADDQ t1, acc2
-	ADCQ $0, DX
-	ADDQ AX, acc2
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ (8*2)(x_ptr), AX
-	MULQ t0
-	ADDQ t1, acc3
-	ADCQ $0, DX
-	ADDQ AX, acc3
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ (8*3)(x_ptr), AX
-	MULQ t0
-	ADDQ t1, acc4
-	ADCQ $0, DX
-	ADDQ AX, acc4
-	ADCQ DX, acc5
-	ADCQ $0, acc0
-	// Second reduction step
-	MOVQ acc1, AX
-	MULQ p256ordK0<>(SB)
-	MOVQ AX, t0
-
-	MOVQ p256ord<>+0x00(SB), AX
-	MULQ t0
-	ADDQ AX, acc1
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ p256ord<>+0x08(SB), AX
-	MULQ t0
-	ADDQ t1, acc2
-	ADCQ $0, DX
-	ADDQ AX, acc2
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ p256ord<>+0x10(SB), AX
-	MULQ t0
-	ADDQ t1, acc3
-	ADCQ $0, DX
-	ADDQ AX, acc3
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ p256ord<>+0x18(SB), AX
-	MULQ t0
-	ADDQ t1, acc4
-	ADCQ $0, DX
-	ADDQ AX, acc4
-	ADCQ DX, acc5
-	ADCQ $0, acc0
-	// x * y[2]
-	MOVQ (8*2)(y_ptr), t0
-
-	MOVQ (8*0)(x_ptr), AX
-	MULQ t0
-	ADDQ AX, acc2
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ (8*1)(x_ptr), AX
-	MULQ t0
-	ADDQ t1, acc3
-	ADCQ $0, DX
-	ADDQ AX, acc3
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ (8*2)(x_ptr), AX
-	MULQ t0
-	ADDQ t1, acc4
-	ADCQ $0, DX
-	ADDQ AX, acc4
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ (8*3)(x_ptr), AX
-	MULQ t0
-	ADDQ t1, acc5
-	ADCQ $0, DX
-	ADDQ AX, acc5
-	ADCQ DX, acc0
-	ADCQ $0, acc1
-	// Third reduction step
-	MOVQ acc2, AX
-	MULQ p256ordK0<>(SB)
-	MOVQ AX, t0
-
-	MOVQ p256ord<>+0x00(SB), AX
-	MULQ t0
-	ADDQ AX, acc2
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ p256ord<>+0x08(SB), AX
-	MULQ t0
-	ADDQ t1, acc3
-	ADCQ $0, DX
-	ADDQ AX, acc3
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ p256ord<>+0x10(SB), AX
-	MULQ t0
-	ADDQ t1, acc4
-	ADCQ $0, DX
-	ADDQ AX, acc4
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ p256ord<>+0x18(SB), AX
-	MULQ t0
-	ADDQ t1, acc5
-	ADCQ $0, DX
-	ADDQ AX, acc5
-	ADCQ DX, acc0
-	ADCQ $0, acc1
-	// x * y[3]
-	MOVQ (8*3)(y_ptr), t0
-
-	MOVQ (8*0)(x_ptr), AX
-	MULQ t0
-	ADDQ AX, acc3
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ (8*1)(x_ptr), AX
-	MULQ t0
-	ADDQ t1, acc4
-	ADCQ $0, DX
-	ADDQ AX, acc4
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ (8*2)(x_ptr), AX
-	MULQ t0
-	ADDQ t1, acc5
-	ADCQ $0, DX
-	ADDQ AX, acc5
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ (8*3)(x_ptr), AX
-	MULQ t0
-	ADDQ t1, acc0
-	ADCQ $0, DX
-	ADDQ AX, acc0
-	ADCQ DX, acc1
-	ADCQ $0, acc2
-	// Last reduction step
-	MOVQ acc3, AX
-	MULQ p256ordK0<>(SB)
-	MOVQ AX, t0
-
-	MOVQ p256ord<>+0x00(SB), AX
-	MULQ t0
-	ADDQ AX, acc3
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ p256ord<>+0x08(SB), AX
-	MULQ t0
-	ADDQ t1, acc4
-	ADCQ $0, DX
-	ADDQ AX, acc4
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ p256ord<>+0x10(SB), AX
-	MULQ t0
-	ADDQ t1, acc5
-	ADCQ $0, DX
-	ADDQ AX, acc5
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ p256ord<>+0x18(SB), AX
-	MULQ t0
-	ADDQ t1, acc0
-	ADCQ $0, DX
-	ADDQ AX, acc0
-	ADCQ DX, acc1
-	ADCQ $0, acc2
-	// Copy result [255:0]
-	MOVQ acc4, x_ptr
-	MOVQ acc5, acc3
-	MOVQ acc0, t0
-	MOVQ acc1, t1
-	// Subtract p256
-	SUBQ p256ord<>+0x00(SB), acc4
-	SBBQ p256ord<>+0x08(SB) ,acc5
-	SBBQ p256ord<>+0x10(SB), acc0
-	SBBQ p256ord<>+0x18(SB), acc1
-	SBBQ $0, acc2
-
-	CMOVQCS x_ptr, acc4
-	CMOVQCS acc3, acc5
-	CMOVQCS t0, acc0
-	CMOVQCS t1, acc1
-
-	MOVQ acc4, (8*0)(res_ptr)
-	MOVQ acc5, (8*1)(res_ptr)
-	MOVQ acc0, (8*2)(res_ptr)
-	MOVQ acc1, (8*3)(res_ptr)
-
-	RET
-/* ---------------------------------------*/
-// func p256OrdSqr(res, in []uint64, n int)
-TEXT ·p256OrdSqr(SB),NOSPLIT,$0
-	MOVQ res+0(FP), res_ptr
-	MOVQ in+24(FP), x_ptr
-	MOVQ n+48(FP), BX
-
-ordSqrLoop:
-
-	// y[1:] * y[0]
-	MOVQ (8*0)(x_ptr), t0
-
-	MOVQ (8*1)(x_ptr), AX
-	MULQ t0
-	MOVQ AX, acc1
-	MOVQ DX, acc2
-
-	MOVQ (8*2)(x_ptr), AX
-	MULQ t0
-	ADDQ AX, acc2
-	ADCQ $0, DX
-	MOVQ DX, acc3
-
-	MOVQ (8*3)(x_ptr), AX
-	MULQ t0
-	ADDQ AX, acc3
-	ADCQ $0, DX
-	MOVQ DX, acc4
-	// y[2:] * y[1]
-	MOVQ (8*1)(x_ptr), t0
-
-	MOVQ (8*2)(x_ptr), AX
-	MULQ t0
-	ADDQ AX, acc3
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ (8*3)(x_ptr), AX
-	MULQ t0
-	ADDQ t1, acc4
-	ADCQ $0, DX
-	ADDQ AX, acc4
-	ADCQ $0, DX
-	MOVQ DX, acc5
-	// y[3] * y[2]
-	MOVQ (8*2)(x_ptr), t0
-
-	MOVQ (8*3)(x_ptr), AX
-	MULQ t0
-	ADDQ AX, acc5
-	ADCQ $0, DX
-	MOVQ DX, y_ptr
-	XORQ t1, t1
-	// *2
-	ADDQ acc1, acc1
-	ADCQ acc2, acc2
-	ADCQ acc3, acc3
-	ADCQ acc4, acc4
-	ADCQ acc5, acc5
-	ADCQ y_ptr, y_ptr
-	ADCQ $0, t1
-	// Missing products
-	MOVQ (8*0)(x_ptr), AX
-	MULQ AX
-	MOVQ AX, acc0
-	MOVQ DX, t0
-
-	MOVQ (8*1)(x_ptr), AX
-	MULQ AX
-	ADDQ t0, acc1
-	ADCQ AX, acc2
-	ADCQ $0, DX
-	MOVQ DX, t0
-
-	MOVQ (8*2)(x_ptr), AX
-	MULQ AX
-	ADDQ t0, acc3
-	ADCQ AX, acc4
-	ADCQ $0, DX
-	MOVQ DX, t0
-
-	MOVQ (8*3)(x_ptr), AX
-	MULQ AX
-	ADDQ t0, acc5
-	ADCQ AX, y_ptr
-	ADCQ DX, t1
-	MOVQ t1, x_ptr
-	// First reduction step
-	MOVQ acc0, AX
-	MULQ p256ordK0<>(SB)
-	MOVQ AX, t0
-
-	MOVQ p256ord<>+0x00(SB), AX
-	MULQ t0
-	ADDQ AX, acc0
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ p256ord<>+0x08(SB), AX
-	MULQ t0
-	ADDQ t1, acc1
-	ADCQ $0, DX
-	ADDQ AX, acc1
-
-	MOVQ t0, t1
-	ADCQ DX, acc2
-	ADCQ $0, t1
-	SUBQ t0, acc2
-	SBBQ $0, t1
-
-	MOVQ t0, AX
-	MOVQ t0, DX
-	MOVQ t0, acc0
-	SHLQ $32, AX
-	SHRQ $32, DX
-
-	ADDQ t1, acc3
-	ADCQ $0, acc0
-	SUBQ AX, acc3
-	SBBQ DX, acc0
-	// Second reduction step
-	MOVQ acc1, AX
-	MULQ p256ordK0<>(SB)
-	MOVQ AX, t0
-
-	MOVQ p256ord<>+0x00(SB), AX
-	MULQ t0
-	ADDQ AX, acc1
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ p256ord<>+0x08(SB), AX
-	MULQ t0
-	ADDQ t1, acc2
-	ADCQ $0, DX
-	ADDQ AX, acc2
-
-	MOVQ t0, t1
-	ADCQ DX, acc3
-	ADCQ $0, t1
-	SUBQ t0, acc3
-	SBBQ $0, t1
-
-	MOVQ t0, AX
-	MOVQ t0, DX
-	MOVQ t0, acc1
-	SHLQ $32, AX
-	SHRQ $32, DX
-
-	ADDQ t1, acc0
-	ADCQ $0, acc1
-	SUBQ AX, acc0
-	SBBQ DX, acc1
-	// Third reduction step
-	MOVQ acc2, AX
-	MULQ p256ordK0<>(SB)
-	MOVQ AX, t0
-
-	MOVQ p256ord<>+0x00(SB), AX
-	MULQ t0
-	ADDQ AX, acc2
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ p256ord<>+0x08(SB), AX
-	MULQ t0
-	ADDQ t1, acc3
-	ADCQ $0, DX
-	ADDQ AX, acc3
-
-	MOVQ t0, t1
-	ADCQ DX, acc0
-	ADCQ $0, t1
-	SUBQ t0, acc0
-	SBBQ $0, t1
-
-	MOVQ t0, AX
-	MOVQ t0, DX
-	MOVQ t0, acc2
-	SHLQ $32, AX
-	SHRQ $32, DX
-
-	ADDQ t1, acc1
-	ADCQ $0, acc2
-	SUBQ AX, acc1
-	SBBQ DX, acc2
-	// Last reduction step
-	MOVQ acc3, AX
-	MULQ p256ordK0<>(SB)
-	MOVQ AX, t0
-
-	MOVQ p256ord<>+0x00(SB), AX
-	MULQ t0
-	ADDQ AX, acc3
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ p256ord<>+0x08(SB), AX
-	MULQ t0
-	ADDQ t1, acc0
-	ADCQ $0, DX
-	ADDQ AX, acc0
-	ADCQ $0, DX
-	MOVQ DX, t1
-
-	MOVQ t0, t1
-	ADCQ DX, acc1
-	ADCQ $0, t1
-	SUBQ t0, acc1
-	SBBQ $0, t1
-
-	MOVQ t0, AX
-	MOVQ t0, DX
-	MOVQ t0, acc3
-	SHLQ $32, AX
-	SHRQ $32, DX
-
-	ADDQ t1, acc2
-	ADCQ $0, acc3
-	SUBQ AX, acc2
-	SBBQ DX, acc3
-	XORQ t0, t0
-	// Add bits [511:256] of the sqr result
-	ADCQ acc4, acc0
-	ADCQ acc5, acc1
-	ADCQ y_ptr, acc2
-	ADCQ x_ptr, acc3
-	ADCQ $0, t0
-
-	MOVQ acc0, acc4
-	MOVQ acc1, acc5
-	MOVQ acc2, y_ptr
-	MOVQ acc3, t1
-	// Subtract p256
-	SUBQ p256ord<>+0x00(SB), acc0
-	SBBQ p256ord<>+0x08(SB) ,acc1
-	SBBQ p256ord<>+0x10(SB), acc2
-	SBBQ p256ord<>+0x18(SB), acc3
-	SBBQ $0, t0
-
-	CMOVQCS acc4, acc0
-	CMOVQCS acc5, acc1
-	CMOVQCS y_ptr, acc2
-	CMOVQCS t1, acc3
-
-	MOVQ acc0, (8*0)(res_ptr)
-	MOVQ acc1, (8*1)(res_ptr)
-	MOVQ acc2, (8*2)(res_ptr)
-	MOVQ acc3, (8*3)(res_ptr)
-	MOVQ res_ptr, x_ptr
-	DECQ BX
-	JNE ordSqrLoop
-
-	RET
-/* ---------------------------------------*/
-#undef res_ptr
-#undef x_ptr
-#undef y_ptr
-
-#undef acc0
-#undef acc1
-#undef acc2
-#undef acc3
-#undef acc4
-#undef acc5
-#undef t0
-#undef t1
-/* ---------------------------------------*/
-#define mul0 AX
-#define mul1 DX
-#define acc0 BX
-#define acc1 CX
-#define acc2 R8
-#define acc3 R9
-#define acc4 R10
-#define acc5 R11
-#define acc6 R12
-#define acc7 R13
-#define t0 R14
-#define t1 R15
-#define t2 DI
-#define t3 SI
-#define hlp BP
-/* ---------------------------------------*/
-TEXT p256SubInternal(SB),NOSPLIT,$0
-	XORQ mul0, mul0
-	SUBQ t0, acc4
-	SBBQ t1, acc5
-	SBBQ t2, acc6
-	SBBQ t3, acc7
-	SBBQ $0, mul0
-
-	MOVQ acc4, acc0
-	MOVQ acc5, acc1
-	MOVQ acc6, acc2
-	MOVQ acc7, acc3
-
-	ADDQ $-1, acc4
-	ADCQ p256const0<>(SB), acc5
-	ADCQ $0, acc6
-	ADCQ p256const1<>(SB), acc7
-	ANDQ $1, mul0
-
-	CMOVQEQ acc0, acc4
-	CMOVQEQ acc1, acc5
-	CMOVQEQ acc2, acc6
-	CMOVQEQ acc3, acc7
-
-	RET
-/* ---------------------------------------*/
-TEXT p256MulInternal(SB),NOSPLIT,$8
-	MOVQ acc4, mul0
-	MULQ t0
-	MOVQ mul0, acc0
-	MOVQ mul1, acc1
-
-	MOVQ acc4, mul0
-	MULQ t1
-	ADDQ mul0, acc1
-	ADCQ $0, mul1
-	MOVQ mul1, acc2
-
-	MOVQ acc4, mul0
-	MULQ t2
-	ADDQ mul0, acc2
-	ADCQ $0, mul1
-	MOVQ mul1, acc3
-
-	MOVQ acc4, mul0
-	MULQ t3
-	ADDQ mul0, acc3
-	ADCQ $0, mul1
-	MOVQ mul1, acc4
-
-	MOVQ acc5, mul0
-	MULQ t0
-	ADDQ mul0, acc1
-	ADCQ $0, mul1
-	MOVQ mul1, hlp
-
-	MOVQ acc5, mul0
-	MULQ t1
-	ADDQ hlp, acc2
-	ADCQ $0, mul1
-	ADDQ mul0, acc2
-	ADCQ $0, mul1
-	MOVQ mul1, hlp
-
-	MOVQ acc5, mul0
-	MULQ t2
-	ADDQ hlp, acc3
-	ADCQ $0, mul1
-	ADDQ mul0, acc3
-	ADCQ $0, mul1
-	MOVQ mul1, hlp
-
-	MOVQ acc5, mul0
-	MULQ t3
-	ADDQ hlp, acc4
-	ADCQ $0, mul1
-	ADDQ mul0, acc4
-	ADCQ $0, mul1
-	MOVQ mul1, acc5
-
-	MOVQ acc6, mul0
-	MULQ t0
-	ADDQ mul0, acc2
-	ADCQ $0, mul1
-	MOVQ mul1, hlp
-
-	MOVQ acc6, mul0
-	MULQ t1
-	ADDQ hlp, acc3
-	ADCQ $0, mul1
-	ADDQ mul0, acc3
-	ADCQ $0, mul1
-	MOVQ mul1, hlp
-
-	MOVQ acc6, mul0
-	MULQ t2
-	ADDQ hlp, acc4
-	ADCQ $0, mul1
-	ADDQ mul0, acc4
-	ADCQ $0, mul1
-	MOVQ mul1, hlp
-
-	MOVQ acc6, mul0
-	MULQ t3
-	ADDQ hlp, acc5
-	ADCQ $0, mul1
-	ADDQ mul0, acc5
-	ADCQ $0, mul1
-	MOVQ mul1, acc6
-
-	MOVQ acc7, mul0
-	MULQ t0
-	ADDQ mul0, acc3
-	ADCQ $0, mul1
-	MOVQ mul1, hlp
-
-	MOVQ acc7, mul0
-	MULQ t1
-	ADDQ hlp, acc4
-	ADCQ $0, mul1
-	ADDQ mul0, acc4
-	ADCQ $0, mul1
-	MOVQ mul1, hlp
-
-	MOVQ acc7, mul0
-	MULQ t2
-	ADDQ hlp, acc5
-	ADCQ $0, mul1
-	ADDQ mul0, acc5
-	ADCQ $0, mul1
-	MOVQ mul1, hlp
-
-	MOVQ acc7, mul0
-	MULQ t3
-	ADDQ hlp, acc6
-	ADCQ $0, mul1
-	ADDQ mul0, acc6
-	ADCQ $0, mul1
-	MOVQ mul1, acc7
-	// First reduction step
-	MOVQ acc0, mul0
-	MOVQ acc0, hlp
-	SHLQ $32, acc0
-	MULQ p256const1<>(SB)
-	SHRQ $32, hlp
-	ADDQ acc0, acc1
-	ADCQ hlp, acc2
-	ADCQ mul0, acc3
-	ADCQ $0, mul1
-	MOVQ mul1, acc0
-	// Second reduction step
-	MOVQ acc1, mul0
-	MOVQ acc1, hlp
-	SHLQ $32, acc1
-	MULQ p256const1<>(SB)
-	SHRQ $32, hlp
-	ADDQ acc1, acc2
-	ADCQ hlp, acc3
-	ADCQ mul0, acc0
-	ADCQ $0, mul1
-	MOVQ mul1, acc1
-	// Third reduction step
-	MOVQ acc2, mul0
-	MOVQ acc2, hlp
-	SHLQ $32, acc2
-	MULQ p256const1<>(SB)
-	SHRQ $32, hlp
-	ADDQ acc2, acc3
-	ADCQ hlp, acc0
-	ADCQ mul0, acc1
-	ADCQ $0, mul1
-	MOVQ mul1, acc2
-	// Last reduction step
-	MOVQ acc3, mul0
-	MOVQ acc3, hlp
-	SHLQ $32, acc3
-	MULQ p256const1<>(SB)
-	SHRQ $32, hlp
-	ADDQ acc3, acc0
-	ADCQ hlp, acc1
-	ADCQ mul0, acc2
-	ADCQ $0, mul1
-	MOVQ mul1, acc3
-	MOVQ $0, BP
-	// Add bits [511:256] of the result
-	ADCQ acc0, acc4
-	ADCQ acc1, acc5
-	ADCQ acc2, acc6
-	ADCQ acc3, acc7
-	ADCQ $0, hlp
-	// Copy result
-	MOVQ acc4, acc0
-	MOVQ acc5, acc1
-	MOVQ acc6, acc2
-	MOVQ acc7, acc3
-	// Subtract p256
-	SUBQ $-1, acc4
-	SBBQ p256const0<>(SB) ,acc5
-	SBBQ $0, acc6
-	SBBQ p256const1<>(SB), acc7
-	SBBQ $0, hlp
-	// If the result of the subtraction is negative, restore the previous result
-	CMOVQCS acc0, acc4
-	CMOVQCS acc1, acc5
-	CMOVQCS acc2, acc6
-	CMOVQCS acc3, acc7
-
-	RET
-/* ---------------------------------------*/
-TEXT p256SqrInternal(SB),NOSPLIT,$8
-
-	MOVQ acc4, mul0
-	MULQ acc5
-	MOVQ mul0, acc1
-	MOVQ mul1, acc2
-
-	MOVQ acc4, mul0
-	MULQ acc6
-	ADDQ mul0, acc2
-	ADCQ $0, mul1
-	MOVQ mul1, acc3
-
-	MOVQ acc4, mul0
-	MULQ acc7
-	ADDQ mul0, acc3
-	ADCQ $0, mul1
-	MOVQ mul1, t0
-
-	MOVQ acc5, mul0
-	MULQ acc6
-	ADDQ mul0, acc3
-	ADCQ $0, mul1
-	MOVQ mul1, hlp
-
-	MOVQ acc5, mul0
-	MULQ acc7
-	ADDQ hlp, t0
-	ADCQ $0, mul1
-	ADDQ mul0, t0
-	ADCQ $0, mul1
-	MOVQ mul1, t1
-
-	MOVQ acc6, mul0
-	MULQ acc7
-	ADDQ mul0, t1
-	ADCQ $0, mul1
-	MOVQ mul1, t2
-	XORQ t3, t3
-	// *2
-	ADDQ acc1, acc1
-	ADCQ acc2, acc2
-	ADCQ acc3, acc3
-	ADCQ t0, t0
-	ADCQ t1, t1
-	ADCQ t2, t2
-	ADCQ $0, t3
-	// Missing products
-	MOVQ acc4, mul0
-	MULQ mul0
-	MOVQ mul0, acc0
-	MOVQ DX, acc4
-
-	MOVQ acc5, mul0
-	MULQ mul0
-	ADDQ acc4, acc1
-	ADCQ mul0, acc2
-	ADCQ $0, DX
-	MOVQ DX, acc4
-
-	MOVQ acc6, mul0
-	MULQ mul0
-	ADDQ acc4, acc3
-	ADCQ mul0, t0
-	ADCQ $0, DX
-	MOVQ DX, acc4
-
-	MOVQ acc7, mul0
-	MULQ mul0
-	ADDQ acc4, t1
-	ADCQ mul0, t2
-	ADCQ DX, t3
-	// First reduction step
-	MOVQ acc0, mul0
-	MOVQ acc0, hlp
-	SHLQ $32, acc0
-	MULQ p256const1<>(SB)
-	SHRQ $32, hlp
-	ADDQ acc0, acc1
-	ADCQ hlp, acc2
-	ADCQ mul0, acc3
-	ADCQ $0, mul1
-	MOVQ mul1, acc0
-	// Second reduction step
-	MOVQ acc1, mul0
-	MOVQ acc1, hlp
-	SHLQ $32, acc1
-	MULQ p256const1<>(SB)
-	SHRQ $32, hlp
-	ADDQ acc1, acc2
-	ADCQ hlp, acc3
-	ADCQ mul0, acc0
-	ADCQ $0, mul1
-	MOVQ mul1, acc1
-	// Third reduction step
-	MOVQ acc2, mul0
-	MOVQ acc2, hlp
-	SHLQ $32, acc2
-	MULQ p256const1<>(SB)
-	SHRQ $32, hlp
-	ADDQ acc2, acc3
-	ADCQ hlp, acc0
-	ADCQ mul0, acc1
-	ADCQ $0, mul1
-	MOVQ mul1, acc2
-	// Last reduction step
-	MOVQ acc3, mul0
-	MOVQ acc3, hlp
-	SHLQ $32, acc3
-	MULQ p256const1<>(SB)
-	SHRQ $32, hlp
-	ADDQ acc3, acc0
-	ADCQ hlp, acc1
-	ADCQ mul0, acc2
-	ADCQ $0, mul1
-	MOVQ mul1, acc3
-	MOVQ $0, BP
-	// Add bits [511:256] of the result
-	ADCQ acc0, t0
-	ADCQ acc1, t1
-	ADCQ acc2, t2
-	ADCQ acc3, t3
-	ADCQ $0, hlp
-	// Copy result
-	MOVQ t0, acc4
-	MOVQ t1, acc5
-	MOVQ t2, acc6
-	MOVQ t3, acc7
-	// Subtract p256
-	SUBQ $-1, acc4
-	SBBQ p256const0<>(SB) ,acc5
-	SBBQ $0, acc6
-	SBBQ p256const1<>(SB), acc7
-	SBBQ $0, hlp
-	// If the result of the subtraction is negative, restore the previous result
-	CMOVQCS t0, acc4
-	CMOVQCS t1, acc5
-	CMOVQCS t2, acc6
-	CMOVQCS t3, acc7
-
-	RET
-/* ---------------------------------------*/
-#define p256MulBy2Inline\
-	XORQ mul0, mul0;\
-	ADDQ acc4, acc4;\
-	ADCQ acc5, acc5;\
-	ADCQ acc6, acc6;\
-	ADCQ acc7, acc7;\
-	ADCQ $0, mul0;\
-	MOVQ acc4, t0;\
-	MOVQ acc5, t1;\
-	MOVQ acc6, t2;\
-	MOVQ acc7, t3;\
-	SUBQ $-1, t0;\
-	SBBQ p256const0<>(SB), t1;\
-	SBBQ $0, t2;\
-	SBBQ p256const1<>(SB), t3;\
-	SBBQ $0, mul0;\
-	CMOVQCS acc4, t0;\
-	CMOVQCS acc5, t1;\
-	CMOVQCS acc6, t2;\
-	CMOVQCS acc7, t3;
-/* ---------------------------------------*/
-#define p256AddInline \
-	XORQ mul0, mul0;\
-	ADDQ t0, acc4;\
-	ADCQ t1, acc5;\
-	ADCQ t2, acc6;\
-	ADCQ t3, acc7;\
-	ADCQ $0, mul0;\
-	MOVQ acc4, t0;\
-	MOVQ acc5, t1;\
-	MOVQ acc6, t2;\
-	MOVQ acc7, t3;\
-	SUBQ $-1, t0;\
-	SBBQ p256const0<>(SB), t1;\
-	SBBQ $0, t2;\
-	SBBQ p256const1<>(SB), t3;\
-	SBBQ $0, mul0;\
-	CMOVQCS acc4, t0;\
-	CMOVQCS acc5, t1;\
-	CMOVQCS acc6, t2;\
-	CMOVQCS acc7, t3;
-/* ---------------------------------------*/
-#define LDacc(src) MOVQ src(8*0), acc4; MOVQ src(8*1), acc5; MOVQ src(8*2), acc6; MOVQ src(8*3), acc7
-#define LDt(src)   MOVQ src(8*0), t0; MOVQ src(8*1), t1; MOVQ src(8*2), t2; MOVQ src(8*3), t3
-#define ST(dst)    MOVQ acc4, dst(8*0); MOVQ acc5, dst(8*1); MOVQ acc6, dst(8*2); MOVQ acc7, dst(8*3)
-#define STt(dst)   MOVQ t0, dst(8*0); MOVQ t1, dst(8*1); MOVQ t2, dst(8*2); MOVQ t3, dst(8*3)
-#define acc2t      MOVQ acc4, t0; MOVQ acc5, t1; MOVQ acc6, t2; MOVQ acc7, t3
-#define t2acc      MOVQ t0, acc4; MOVQ t1, acc5; MOVQ t2, acc6; MOVQ t3, acc7
-/* ---------------------------------------*/
-#define x1in(off) (32*0 + off)(SP)
-#define y1in(off) (32*1 + off)(SP)
-#define z1in(off) (32*2 + off)(SP)
-#define x2in(off) (32*3 + off)(SP)
-#define y2in(off) (32*4 + off)(SP)
-#define xout(off) (32*5 + off)(SP)
-#define yout(off) (32*6 + off)(SP)
-#define zout(off) (32*7 + off)(SP)
-#define s2(off)   (32*8 + off)(SP)
-#define z1sqr(off) (32*9 + off)(SP)
-#define h(off)	  (32*10 + off)(SP)
-#define r(off)	  (32*11 + off)(SP)
-#define hsqr(off) (32*12 + off)(SP)
-#define rsqr(off) (32*13 + off)(SP)
-#define hcub(off) (32*14 + off)(SP)
-#define rptr	  (32*15)(SP)
-#define sel_save  (32*15 + 8)(SP)
-#define zero_save (32*15 + 8 + 4)(SP)
-
-// func p256PointAddAffineAsm(res, in1, in2 []uint64, sign, sel, zero int)
-TEXT ·p256PointAddAffineAsm(SB),0,$512-96
-	// Move input to stack in order to free registers
-	MOVQ res+0(FP), AX
-	MOVQ in1+24(FP), BX
-	MOVQ in2+48(FP), CX
-	MOVQ sign+72(FP), DX
-	MOVQ sel+80(FP), t1
-	MOVQ zero+88(FP), t2
-
-	MOVOU (16*0)(BX), X0
-	MOVOU (16*1)(BX), X1
-	MOVOU (16*2)(BX), X2
-	MOVOU (16*3)(BX), X3
-	MOVOU (16*4)(BX), X4
-	MOVOU (16*5)(BX), X5
-
-	MOVOU X0, x1in(16*0)
-	MOVOU X1, x1in(16*1)
-	MOVOU X2, y1in(16*0)
-	MOVOU X3, y1in(16*1)
-	MOVOU X4, z1in(16*0)
-	MOVOU X5, z1in(16*1)
-
-	MOVOU (16*0)(CX), X0
-	MOVOU (16*1)(CX), X1
-
-	MOVOU X0, x2in(16*0)
-	MOVOU X1, x2in(16*1)
-	// Store pointer to result
-	MOVQ mul0, rptr
-	MOVL t1, sel_save
-	MOVL t2, zero_save
-	// Negate y2in based on sign
-	MOVQ (16*2 + 8*0)(CX), acc4
-	MOVQ (16*2 + 8*1)(CX), acc5
-	MOVQ (16*2 + 8*2)(CX), acc6
-	MOVQ (16*2 + 8*3)(CX), acc7
-	MOVQ $-1, acc0
-	MOVQ p256const0<>(SB), acc1
-	MOVQ $0, acc2
-	MOVQ p256const1<>(SB), acc3
-	XORQ mul0, mul0
-	// Speculatively subtract
-	SUBQ acc4, acc0
-	SBBQ acc5, acc1
-	SBBQ acc6, acc2
-	SBBQ acc7, acc3
-	SBBQ $0, mul0
-	MOVQ acc0, t0
-	MOVQ acc1, t1
-	MOVQ acc2, t2
-	MOVQ acc3, t3
-	// Add in case the operand was > p256
-	ADDQ $-1, acc0
-	ADCQ p256const0<>(SB), acc1
-	ADCQ $0, acc2
-	ADCQ p256const1<>(SB), acc3
-	ADCQ $0, mul0
-	CMOVQNE t0, acc0
-	CMOVQNE t1, acc1
-	CMOVQNE t2, acc2
-	CMOVQNE t3, acc3
-	// If condition is 0, keep original value
-	TESTQ DX, DX
-	CMOVQEQ acc4, acc0
-	CMOVQEQ acc5, acc1
-	CMOVQEQ acc6, acc2
-	CMOVQEQ acc7, acc3
-	// Store result
-	MOVQ acc0, y2in(8*0)
-	MOVQ acc1, y2in(8*1)
-	MOVQ acc2, y2in(8*2)
-	MOVQ acc3, y2in(8*3)
-	// Begin point add
-	LDacc (z1in)
-	CALL p256SqrInternal(SB)	// z1ˆ2
-	ST (z1sqr)
-
-	LDt (x2in)
-	CALL p256MulInternal(SB)	// x2 * z1ˆ2
-
-	LDt (x1in)
-	CALL p256SubInternal(SB)	// h = u2 - u1
-	ST (h)
-
-	LDt (z1in)
-	CALL p256MulInternal(SB)	// z3 = h * z1
-	ST (zout)
-
-	LDacc (z1sqr)
-	CALL p256MulInternal(SB)	// z1ˆ3
-
-	LDt (y2in)
-	CALL p256MulInternal(SB)	// s2 = y2 * z1ˆ3
-	ST (s2)
-
-	LDt (y1in)
-	CALL p256SubInternal(SB)	// r = s2 - s1
-	ST (r)
-
-	CALL p256SqrInternal(SB)	// rsqr = rˆ2
-	ST (rsqr)
-
-	LDacc (h)
-	CALL p256SqrInternal(SB)	// hsqr = hˆ2
-	ST (hsqr)
-
-	LDt (h)
-	CALL p256MulInternal(SB)	// hcub = hˆ3
-	ST (hcub)
-
-	LDt (y1in)
-	CALL p256MulInternal(SB)	// y1 * hˆ3
-	ST (s2)
-
-	LDacc (x1in)
-	LDt (hsqr)
-	CALL p256MulInternal(SB)	// u1 * hˆ2
-	ST (h)
-
-	p256MulBy2Inline			// u1 * hˆ2 * 2, inline
-	LDacc (rsqr)
-	CALL p256SubInternal(SB)	// rˆ2 - u1 * hˆ2 * 2
-
-	LDt (hcub)
-	CALL p256SubInternal(SB)
-	ST (xout)
-
-	MOVQ acc4, t0
-	MOVQ acc5, t1
-	MOVQ acc6, t2
-	MOVQ acc7, t3
-	LDacc (h)
-	CALL p256SubInternal(SB)
-
-	LDt (r)
-	CALL p256MulInternal(SB)
-
-	LDt (s2)
-	CALL p256SubInternal(SB)
-	ST (yout)
-	// Load stored values from stack
-	MOVQ rptr, AX
-	MOVL sel_save, BX
-	MOVL zero_save, CX
-	// The result is not valid if (sel == 0), conditional choose
-	MOVOU xout(16*0), X0
-	MOVOU xout(16*1), X1
-	MOVOU yout(16*0), X2
-	MOVOU yout(16*1), X3
-	MOVOU zout(16*0), X4
-	MOVOU zout(16*1), X5
-
-	MOVL BX, X6
-	MOVL CX, X7
-
-	PXOR X8, X8
-	PCMPEQL X9, X9
-
-	PSHUFD $0, X6, X6
-	PSHUFD $0, X7, X7
-
-	PCMPEQL X8, X6
-	PCMPEQL X8, X7
-
-	MOVOU X6, X15
-	PANDN X9, X15
-
-	MOVOU x1in(16*0), X9
-	MOVOU x1in(16*1), X10
-	MOVOU y1in(16*0), X11
-	MOVOU y1in(16*1), X12
-	MOVOU z1in(16*0), X13
-	MOVOU z1in(16*1), X14
-
-	PAND X15, X0
-	PAND X15, X1
-	PAND X15, X2
-	PAND X15, X3
-	PAND X15, X4
-	PAND X15, X5
-
-	PAND X6, X9
-	PAND X6, X10
-	PAND X6, X11
-	PAND X6, X12
-	PAND X6, X13
-	PAND X6, X14
-
-	PXOR X9, X0
-	PXOR X10, X1
-	PXOR X11, X2
-	PXOR X12, X3
-	PXOR X13, X4
-	PXOR X14, X5
-	// Similarly if zero == 0
-	PCMPEQL X9, X9
-	MOVOU X7, X15
-	PANDN X9, X15
-
-	MOVOU x2in(16*0), X9
-	MOVOU x2in(16*1), X10
-	MOVOU y2in(16*0), X11
-	MOVOU y2in(16*1), X12
-	MOVOU p256one<>+0x00(SB), X13
-	MOVOU p256one<>+0x10(SB), X14
-
-	PAND X15, X0
-	PAND X15, X1
-	PAND X15, X2
-	PAND X15, X3
-	PAND X15, X4
-	PAND X15, X5
-
-	PAND X7, X9
-	PAND X7, X10
-	PAND X7, X11
-	PAND X7, X12
-	PAND X7, X13
-	PAND X7, X14
-
-	PXOR X9, X0
-	PXOR X10, X1
-	PXOR X11, X2
-	PXOR X12, X3
-	PXOR X13, X4
-	PXOR X14, X5
-	// Finally output the result
-	MOVOU X0, (16*0)(AX)
-	MOVOU X1, (16*1)(AX)
-	MOVOU X2, (16*2)(AX)
-	MOVOU X3, (16*3)(AX)
-	MOVOU X4, (16*4)(AX)
-	MOVOU X5, (16*5)(AX)
-	MOVQ $0, rptr
-
-	RET
-#undef x1in
-#undef y1in
-#undef z1in
-#undef x2in
-#undef y2in
-#undef xout
-#undef yout
-#undef zout
-#undef s2
-#undef z1sqr
-#undef h
-#undef r
-#undef hsqr
-#undef rsqr
-#undef hcub
-#undef rptr
-#undef sel_save
-#undef zero_save
-
-// p256IsZero returns 1 in AX if [acc4..acc7] represents zero and zero
-// otherwise. It writes to [acc4..acc7], t0 and t1.
-TEXT p256IsZero(SB),NOSPLIT,$0
-	// AX contains a flag that is set if the input is zero.
-	XORQ AX, AX
-	MOVQ $1, t1
-
-	// Check whether [acc4..acc7] are all zero.
-	MOVQ acc4, t0
-	ORQ acc5, t0
-	ORQ acc6, t0
-	ORQ acc7, t0
-
-	// Set the zero flag if so. (CMOV of a constant to a register doesn't
-	// appear to be supported in Go. Thus t1 = 1.)
-	CMOVQEQ t1, AX
-
-	// XOR [acc4..acc7] with P and compare with zero again.
-	XORQ $-1, acc4
-	XORQ p256const0<>(SB), acc5
-	XORQ p256const1<>(SB), acc7
-	ORQ acc5, acc4
-	ORQ acc6, acc4
-	ORQ acc7, acc4
-
-	// Set the zero flag if so.
-	CMOVQEQ t1, AX
-	RET
-
-/* ---------------------------------------*/
-#define x1in(off) (32*0 + off)(SP)
-#define y1in(off) (32*1 + off)(SP)
-#define z1in(off) (32*2 + off)(SP)
-#define x2in(off) (32*3 + off)(SP)
-#define y2in(off) (32*4 + off)(SP)
-#define z2in(off) (32*5 + off)(SP)
-
-#define xout(off) (32*6 + off)(SP)
-#define yout(off) (32*7 + off)(SP)
-#define zout(off) (32*8 + off)(SP)
-
-#define u1(off)    (32*9 + off)(SP)
-#define u2(off)    (32*10 + off)(SP)
-#define s1(off)    (32*11 + off)(SP)
-#define s2(off)    (32*12 + off)(SP)
-#define z1sqr(off) (32*13 + off)(SP)
-#define z2sqr(off) (32*14 + off)(SP)
-#define h(off)     (32*15 + off)(SP)
-#define r(off)     (32*16 + off)(SP)
-#define hsqr(off)  (32*17 + off)(SP)
-#define rsqr(off)  (32*18 + off)(SP)
-#define hcub(off)  (32*19 + off)(SP)
-#define rptr       (32*20)(SP)
-#define points_eq  (32*20+8)(SP)
-
-//func p256PointAddAsm(res, in1, in2 []uint64) int
-TEXT ·p256PointAddAsm(SB),0,$680-80
-	// See https://hyperelliptic.org/EFD/g1p/auto-shortw-jacobian-3.html#addition-add-2007-bl
-	// Move input to stack in order to free registers
-	MOVQ res+0(FP), AX
-	MOVQ in1+24(FP), BX
-	MOVQ in2+48(FP), CX
-
-	MOVOU (16*0)(BX), X0
-	MOVOU (16*1)(BX), X1
-	MOVOU (16*2)(BX), X2
-	MOVOU (16*3)(BX), X3
-	MOVOU (16*4)(BX), X4
-	MOVOU (16*5)(BX), X5
-
-	MOVOU X0, x1in(16*0)
-	MOVOU X1, x1in(16*1)
-	MOVOU X2, y1in(16*0)
-	MOVOU X3, y1in(16*1)
-	MOVOU X4, z1in(16*0)
-	MOVOU X5, z1in(16*1)
-
-	MOVOU (16*0)(CX), X0
-	MOVOU (16*1)(CX), X1
-	MOVOU (16*2)(CX), X2
-	MOVOU (16*3)(CX), X3
-	MOVOU (16*4)(CX), X4
-	MOVOU (16*5)(CX), X5
-
-	MOVOU X0, x2in(16*0)
-	MOVOU X1, x2in(16*1)
-	MOVOU X2, y2in(16*0)
-	MOVOU X3, y2in(16*1)
-	MOVOU X4, z2in(16*0)
-	MOVOU X5, z2in(16*1)
-	// Store pointer to result
-	MOVQ AX, rptr
-	// Begin point add
-	LDacc (z2in)
-	CALL p256SqrInternal(SB)	// z2ˆ2
-	ST (z2sqr)
-	LDt (z2in)
-	CALL p256MulInternal(SB)	// z2ˆ3
-	LDt (y1in)
-	CALL p256MulInternal(SB)	// s1 = z2ˆ3*y1
-	ST (s1)
-
-	LDacc (z1in)
-	CALL p256SqrInternal(SB)	// z1ˆ2
-	ST (z1sqr)
-	LDt (z1in)
-	CALL p256MulInternal(SB)	// z1ˆ3
-	LDt (y2in)
-	CALL p256MulInternal(SB)	// s2 = z1ˆ3*y2
-	ST (s2)
-
-	LDt (s1)
-	CALL p256SubInternal(SB)	// r = s2 - s1
-	ST (r)
-	CALL p256IsZero(SB)
-	MOVQ AX, points_eq
-
-	LDacc (z2sqr)
-	LDt (x1in)
-	CALL p256MulInternal(SB)	// u1 = x1 * z2ˆ2
-	ST (u1)
-	LDacc (z1sqr)
-	LDt (x2in)
-	CALL p256MulInternal(SB)	// u2 = x2 * z1ˆ2
-	ST (u2)
-
-	LDt (u1)
-	CALL p256SubInternal(SB)	// h = u2 - u1
-	ST (h)
-	CALL p256IsZero(SB)
-	ANDQ points_eq, AX
-	MOVQ AX, points_eq
-
-	LDacc (r)
-	CALL p256SqrInternal(SB)	// rsqr = rˆ2
-	ST (rsqr)
-
-	LDacc (h)
-	CALL p256SqrInternal(SB)	// hsqr = hˆ2
-	ST (hsqr)
-
-	LDt (h)
-	CALL p256MulInternal(SB)	// hcub = hˆ3
-	ST (hcub)
-
-	LDt (s1)
-	CALL p256MulInternal(SB)
-	ST (s2)
-
-	LDacc (z1in)
-	LDt (z2in)
-	CALL p256MulInternal(SB)	// z1 * z2
-	LDt (h)
-	CALL p256MulInternal(SB)	// z1 * z2 * h
-	ST (zout)
-
-	LDacc (hsqr)
-	LDt (u1)
-	CALL p256MulInternal(SB)	// hˆ2 * u1
-	ST (u2)
-
-	p256MulBy2Inline	// u1 * hˆ2 * 2, inline
-	LDacc (rsqr)
-	CALL p256SubInternal(SB)	// rˆ2 - u1 * hˆ2 * 2
-
-	LDt (hcub)
-	CALL p256SubInternal(SB)
-	ST (xout)
-
-	MOVQ acc4, t0
-	MOVQ acc5, t1
-	MOVQ acc6, t2
-	MOVQ acc7, t3
-	LDacc (u2)
-	CALL p256SubInternal(SB)
-
-	LDt (r)
-	CALL p256MulInternal(SB)
-
-	LDt (s2)
-	CALL p256SubInternal(SB)
-	ST (yout)
-
-	MOVOU xout(16*0), X0
-	MOVOU xout(16*1), X1
-	MOVOU yout(16*0), X2
-	MOVOU yout(16*1), X3
-	MOVOU zout(16*0), X4
-	MOVOU zout(16*1), X5
-	// Finally output the result
-	MOVQ rptr, AX
-	MOVQ $0, rptr
-	MOVOU X0, (16*0)(AX)
-	MOVOU X1, (16*1)(AX)
-	MOVOU X2, (16*2)(AX)
-	MOVOU X3, (16*3)(AX)
-	MOVOU X4, (16*4)(AX)
-	MOVOU X5, (16*5)(AX)
-
-	MOVQ points_eq, AX
-	MOVQ AX, ret+72(FP)
-
-	RET
-#undef x1in
-#undef y1in
-#undef z1in
-#undef x2in
-#undef y2in
-#undef z2in
-#undef xout
-#undef yout
-#undef zout
-#undef s1
-#undef s2
-#undef u1
-#undef u2
-#undef z1sqr
-#undef z2sqr
-#undef h
-#undef r
-#undef hsqr
-#undef rsqr
-#undef hcub
-#undef rptr
-/* ---------------------------------------*/
-#define x(off) (32*0 + off)(SP)
-#define y(off) (32*1 + off)(SP)
-#define z(off) (32*2 + off)(SP)
-
-#define s(off)	(32*3 + off)(SP)
-#define m(off)	(32*4 + off)(SP)
-#define zsqr(off) (32*5 + off)(SP)
-#define tmp(off)  (32*6 + off)(SP)
-#define rptr	  (32*7)(SP)
-
-//func p256PointDoubleAsm(res, in []uint64)
-TEXT ·p256PointDoubleAsm(SB),NOSPLIT,$256-48
-	// Move input to stack in order to free registers
-	MOVQ res+0(FP), AX
-	MOVQ in+24(FP), BX
-
-	MOVOU (16*0)(BX), X0
-	MOVOU (16*1)(BX), X1
-	MOVOU (16*2)(BX), X2
-	MOVOU (16*3)(BX), X3
-	MOVOU (16*4)(BX), X4
-	MOVOU (16*5)(BX), X5
-
-	MOVOU X0, x(16*0)
-	MOVOU X1, x(16*1)
-	MOVOU X2, y(16*0)
-	MOVOU X3, y(16*1)
-	MOVOU X4, z(16*0)
-	MOVOU X5, z(16*1)
-	// Store pointer to result
-	MOVQ AX, rptr
-	// Begin point double
-	LDacc (z)
-	CALL p256SqrInternal(SB)
-	ST (zsqr)
-
-	LDt (x)
-	p256AddInline
-	STt (m)
-
-	LDacc (z)
-	LDt (y)
-	CALL p256MulInternal(SB)
-	p256MulBy2Inline
-	MOVQ rptr, AX
-	// Store z
-	MOVQ t0, (16*4 + 8*0)(AX)
-	MOVQ t1, (16*4 + 8*1)(AX)
-	MOVQ t2, (16*4 + 8*2)(AX)
-	MOVQ t3, (16*4 + 8*3)(AX)
-
-	LDacc (x)
-	LDt (zsqr)
-	CALL p256SubInternal(SB)
-	LDt (m)
-	CALL p256MulInternal(SB)
-	ST (m)
-	// Multiply by 3
-	p256MulBy2Inline
-	LDacc (m)
-	p256AddInline
-	STt (m)
-	////////////////////////
-	LDacc (y)
-	p256MulBy2Inline
-	t2acc
-	CALL p256SqrInternal(SB)
-	ST (s)
-	CALL p256SqrInternal(SB)
-	// Divide by 2
-	XORQ mul0, mul0
-	MOVQ acc4, t0
-	MOVQ acc5, t1
-	MOVQ acc6, t2
-	MOVQ acc7, t3
-
-	ADDQ $-1, acc4
-	ADCQ p256const0<>(SB), acc5
-	ADCQ $0, acc6
-	ADCQ p256const1<>(SB), acc7
-	ADCQ $0, mul0
-	TESTQ $1, t0
-
-	CMOVQEQ t0, acc4
-	CMOVQEQ t1, acc5
-	CMOVQEQ t2, acc6
-	CMOVQEQ t3, acc7
-	ANDQ t0, mul0
-
-	SHRQ $1, acc5, acc4
-	SHRQ $1, acc6, acc5
-	SHRQ $1, acc7, acc6
-	SHRQ $1, mul0, acc7
-	ST (y)
-	/////////////////////////
-	LDacc (x)
-	LDt (s)
-	CALL p256MulInternal(SB)
-	ST (s)
-	p256MulBy2Inline
-	STt (tmp)
-
-	LDacc (m)
-	CALL p256SqrInternal(SB)
-	LDt (tmp)
-	CALL p256SubInternal(SB)
-
-	MOVQ rptr, AX
-	// Store x
-	MOVQ acc4, (16*0 + 8*0)(AX)
-	MOVQ acc5, (16*0 + 8*1)(AX)
-	MOVQ acc6, (16*0 + 8*2)(AX)
-	MOVQ acc7, (16*0 + 8*3)(AX)
-
-	acc2t
-	LDacc (s)
-	CALL p256SubInternal(SB)
-
-	LDt (m)
-	CALL p256MulInternal(SB)
-
-	LDt (y)
-	CALL p256SubInternal(SB)
-	MOVQ rptr, AX
-	// Store y
-	MOVQ acc4, (16*2 + 8*0)(AX)
-	MOVQ acc5, (16*2 + 8*1)(AX)
-	MOVQ acc6, (16*2 + 8*2)(AX)
-	MOVQ acc7, (16*2 + 8*3)(AX)
-	///////////////////////
-	MOVQ $0, rptr
-
-	RET
-/* ---------------------------------------*/
diff --git a/contrib/go/_std_1.18/src/crypto/elliptic/p384.go b/contrib/go/_std_1.18/src/crypto/elliptic/p384.go
deleted file mode 100644
index 33a441d090..0000000000
--- a/contrib/go/_std_1.18/src/crypto/elliptic/p384.go
+++ /dev/null
@@ -1,144 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package elliptic
-
-import (
-	"crypto/elliptic/internal/nistec"
-	"crypto/rand"
-	"math/big"
-)
-
-// p384Curve is a Curve implementation based on nistec.P384Point.
-//
-// It's a wrapper that exposes the big.Int-based Curve interface and encodes the
-// legacy idiosyncrasies it requires, such as invalid and infinity point
-// handling.
-//
-// To interact with the nistec package, points are encoded into and decoded from
-// properly formatted byte slices. All big.Int use is limited to this package.
-// Encoding and decoding is 1/1000th of the runtime of a scalar multiplication,
-// so the overhead is acceptable.
-type p384Curve struct {
-	params *CurveParams
-}
-
-var p384 p384Curve
-var _ Curve = p384
-
-func initP384() {
-	p384.params = &CurveParams{
-		Name:    "P-384",
-		BitSize: 384,
-		// FIPS 186-4, section D.1.2.4
-		P: bigFromDecimal("394020061963944792122790401001436138050797392704654" +
-			"46667948293404245721771496870329047266088258938001861606973112319"),
-		N: bigFromDecimal("394020061963944792122790401001436138050797392704654" +
-			"46667946905279627659399113263569398956308152294913554433653942643"),
-		B: bigFromHex("b3312fa7e23ee7e4988e056be3f82d19181d9c6efe8141120314088" +
-			"f5013875ac656398d8a2ed19d2a85c8edd3ec2aef"),
-		Gx: bigFromHex("aa87ca22be8b05378eb1c71ef320ad746e1d3b628ba79b9859f741" +
-			"e082542a385502f25dbf55296c3a545e3872760ab7"),
-		Gy: bigFromHex("3617de4a96262c6f5d9e98bf9292dc29f8f41dbd289a147ce9da31" +
-			"13b5f0b8c00a60b1ce1d7e819d7a431d7c90ea0e5f"),
-	}
-}
-
-func (curve p384Curve) Params() *CurveParams {
-	return curve.params
-}
-
-func (curve p384Curve) IsOnCurve(x, y *big.Int) bool {
-	// IsOnCurve is documented to reject (0, 0), the conventional point at
-	// infinity, which however is accepted by p384PointFromAffine.
-	if x.Sign() == 0 && y.Sign() == 0 {
-		return false
-	}
-	_, ok := p384PointFromAffine(x, y)
-	return ok
-}
-
-func p384PointFromAffine(x, y *big.Int) (p *nistec.P384Point, ok bool) {
-	// (0, 0) is by convention the point at infinity, which can't be represented
-	// in affine coordinates. Marshal incorrectly encodes it as an uncompressed
-	// point, which SetBytes would correctly reject. See Issue 37294.
-	if x.Sign() == 0 && y.Sign() == 0 {
-		return nistec.NewP384Point(), true
-	}
-	if x.Sign() < 0 || y.Sign() < 0 {
-		return nil, false
-	}
-	if x.BitLen() > 384 || y.BitLen() > 384 {
-		return nil, false
-	}
-	p, err := nistec.NewP384Point().SetBytes(Marshal(P384(), x, y))
-	if err != nil {
-		return nil, false
-	}
-	return p, true
-}
-
-func p384PointToAffine(p *nistec.P384Point) (x, y *big.Int) {
-	out := p.Bytes()
-	if len(out) == 1 && out[0] == 0 {
-		// This is the correct encoding of the point at infinity, which
-		// Unmarshal does not support. See Issue 37294.
-		return new(big.Int), new(big.Int)
-	}
-	x, y = Unmarshal(P384(), out)
-	if x == nil {
-		panic("crypto/elliptic: internal error: Unmarshal rejected a valid point encoding")
-	}
-	return x, y
-}
-
-// p384RandomPoint returns a random point on the curve. It's used when Add,
-// Double, or ScalarMult are fed a point not on the curve, which is undefined
-// behavior. Originally, we used to do the math on it anyway (which allows
-// invalid curve attacks) and relied on the caller and Unmarshal to avoid this
-// happening in the first place. Now, we just can't construct a nistec.P384Point
-// for an invalid pair of coordinates, because that API is safer. If we panic,
-// we risk introducing a DoS. If we return nil, we risk a panic. If we return
-// the input, ecdsa.Verify might fail open. The safest course seems to be to
-// return a valid, random point, which hopefully won't help the attacker.
-func p384RandomPoint() (x, y *big.Int) {
-	_, x, y, err := GenerateKey(P384(), rand.Reader)
-	if err != nil {
-		panic("crypto/elliptic: failed to generate random point")
-	}
-	return x, y
-}
-
-func (p384Curve) Add(x1, y1, x2, y2 *big.Int) (*big.Int, *big.Int) {
-	p1, ok := p384PointFromAffine(x1, y1)
-	if !ok {
-		return p384RandomPoint()
-	}
-	p2, ok := p384PointFromAffine(x2, y2)
-	if !ok {
-		return p384RandomPoint()
-	}
-	return p384PointToAffine(p1.Add(p1, p2))
-}
-
-func (p384Curve) Double(x1, y1 *big.Int) (*big.Int, *big.Int) {
-	p, ok := p384PointFromAffine(x1, y1)
-	if !ok {
-		return p384RandomPoint()
-	}
-	return p384PointToAffine(p.Double(p))
-}
-
-func (p384Curve) ScalarMult(Bx, By *big.Int, scalar []byte) (*big.Int, *big.Int) {
-	p, ok := p384PointFromAffine(Bx, By)
-	if !ok {
-		return p384RandomPoint()
-	}
-	return p384PointToAffine(p.ScalarMult(p, scalar))
-}
-
-func (p384Curve) ScalarBaseMult(scalar []byte) (*big.Int, *big.Int) {
-	p := nistec.NewP384Generator()
-	return p384PointToAffine(p.ScalarMult(p, scalar))
-}
diff --git a/contrib/go/_std_1.18/src/crypto/elliptic/p521.go b/contrib/go/_std_1.18/src/crypto/elliptic/p521.go
deleted file mode 100644
index 6a3ade3c36..0000000000
--- a/contrib/go/_std_1.18/src/crypto/elliptic/p521.go
+++ /dev/null
@@ -1,165 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package elliptic
-
-import (
-	"crypto/elliptic/internal/nistec"
-	"crypto/rand"
-	"math/big"
-)
-
-// p521Curve is a Curve implementation based on nistec.P521Point.
-//
-// It's a wrapper that exposes the big.Int-based Curve interface and encodes the
-// legacy idiosyncrasies it requires, such as invalid and infinity point
-// handling.
-//
-// To interact with the nistec package, points are encoded into and decoded from
-// properly formatted byte slices. All big.Int use is limited to this package.
-// Encoding and decoding is 1/1000th of the runtime of a scalar multiplication,
-// so the overhead is acceptable.
-type p521Curve struct {
-	params *CurveParams
-}
-
-var p521 p521Curve
-var _ Curve = p521
-
-func initP521() {
-	p521.params = &CurveParams{
-		Name:    "P-521",
-		BitSize: 521,
-		// FIPS 186-4, section D.1.2.5
-		P: bigFromDecimal("68647976601306097149819007990813932172694353001433" +
-			"0540939446345918554318339765605212255964066145455497729631139148" +
-			"0858037121987999716643812574028291115057151"),
-		N: bigFromDecimal("68647976601306097149819007990813932172694353001433" +
-			"0540939446345918554318339765539424505774633321719753296399637136" +
-			"3321113864768612440380340372808892707005449"),
-		B: bigFromHex("0051953eb9618e1c9a1f929a21a0b68540eea2da725b99b315f3b8" +
-			"b489918ef109e156193951ec7e937b1652c0bd3bb1bf073573df883d2c34f1ef" +
-			"451fd46b503f00"),
-		Gx: bigFromHex("00c6858e06b70404e9cd9e3ecb662395b4429c648139053fb521f8" +
-			"28af606b4d3dbaa14b5e77efe75928fe1dc127a2ffa8de3348b3c1856a429bf9" +
-			"7e7e31c2e5bd66"),
-		Gy: bigFromHex("011839296a789a3bc0045c8a5fb42c7d1bd998f54449579b446817" +
-			"afbd17273e662c97ee72995ef42640c550b9013fad0761353c7086a272c24088" +
-			"be94769fd16650"),
-	}
-}
-
-func (curve p521Curve) Params() *CurveParams {
-	return curve.params
-}
-
-func (curve p521Curve) IsOnCurve(x, y *big.Int) bool {
-	// IsOnCurve is documented to reject (0, 0), the conventional point at
-	// infinity, which however is accepted by p521PointFromAffine.
-	if x.Sign() == 0 && y.Sign() == 0 {
-		return false
-	}
-	_, ok := p521PointFromAffine(x, y)
-	return ok
-}
-
-func p521PointFromAffine(x, y *big.Int) (p *nistec.P521Point, ok bool) {
-	// (0, 0) is by convention the point at infinity, which can't be represented
-	// in affine coordinates. Marshal incorrectly encodes it as an uncompressed
-	// point, which SetBytes would correctly reject. See Issue 37294.
-	if x.Sign() == 0 && y.Sign() == 0 {
-		return nistec.NewP521Point(), true
-	}
-	if x.Sign() < 0 || y.Sign() < 0 {
-		return nil, false
-	}
-	if x.BitLen() > 521 || y.BitLen() > 521 {
-		return nil, false
-	}
-	p, err := nistec.NewP521Point().SetBytes(Marshal(P521(), x, y))
-	if err != nil {
-		return nil, false
-	}
-	return p, true
-}
-
-func p521PointToAffine(p *nistec.P521Point) (x, y *big.Int) {
-	out := p.Bytes()
-	if len(out) == 1 && out[0] == 0 {
-		// This is the correct encoding of the point at infinity, which
-		// Unmarshal does not support. See Issue 37294.
-		return new(big.Int), new(big.Int)
-	}
-	x, y = Unmarshal(P521(), out)
-	if x == nil {
-		panic("crypto/elliptic: internal error: Unmarshal rejected a valid point encoding")
-	}
-	return x, y
-}
-
-// p521RandomPoint returns a random point on the curve. It's used when Add,
-// Double, or ScalarMult are fed a point not on the curve, which is undefined
-// behavior. Originally, we used to do the math on it anyway (which allows
-// invalid curve attacks) and relied on the caller and Unmarshal to avoid this
-// happening in the first place. Now, we just can't construct a nistec.P521Point
-// for an invalid pair of coordinates, because that API is safer. If we panic,
-// we risk introducing a DoS. If we return nil, we risk a panic. If we return
-// the input, ecdsa.Verify might fail open. The safest course seems to be to
-// return a valid, random point, which hopefully won't help the attacker.
-func p521RandomPoint() (x, y *big.Int) {
-	_, x, y, err := GenerateKey(P521(), rand.Reader)
-	if err != nil {
-		panic("crypto/elliptic: failed to generate random point")
-	}
-	return x, y
-}
-
-func (p521Curve) Add(x1, y1, x2, y2 *big.Int) (*big.Int, *big.Int) {
-	p1, ok := p521PointFromAffine(x1, y1)
-	if !ok {
-		return p521RandomPoint()
-	}
-	p2, ok := p521PointFromAffine(x2, y2)
-	if !ok {
-		return p521RandomPoint()
-	}
-	return p521PointToAffine(p1.Add(p1, p2))
-}
-
-func (p521Curve) Double(x1, y1 *big.Int) (*big.Int, *big.Int) {
-	p, ok := p521PointFromAffine(x1, y1)
-	if !ok {
-		return p521RandomPoint()
-	}
-	return p521PointToAffine(p.Double(p))
-}
-
-func (p521Curve) ScalarMult(Bx, By *big.Int, scalar []byte) (*big.Int, *big.Int) {
-	p, ok := p521PointFromAffine(Bx, By)
-	if !ok {
-		return p521RandomPoint()
-	}
-	return p521PointToAffine(p.ScalarMult(p, scalar))
-}
-
-func (p521Curve) ScalarBaseMult(scalar []byte) (*big.Int, *big.Int) {
-	p := nistec.NewP521Generator()
-	return p521PointToAffine(p.ScalarMult(p, scalar))
-}
-
-func bigFromDecimal(s string) *big.Int {
-	b, ok := new(big.Int).SetString(s, 10)
-	if !ok {
-		panic("invalid encoding")
-	}
-	return b
-}
-
-func bigFromHex(s string) *big.Int {
-	b, ok := new(big.Int).SetString(s, 16)
-	if !ok {
-		panic("invalid encoding")
-	}
-	return b
-}
diff --git a/contrib/go/_std_1.18/src/crypto/hmac/hmac.go b/contrib/go/_std_1.18/src/crypto/hmac/hmac.go
deleted file mode 100644
index cdda33c2cb..0000000000
--- a/contrib/go/_std_1.18/src/crypto/hmac/hmac.go
+++ /dev/null
@@ -1,172 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-/*
-Package hmac implements the Keyed-Hash Message Authentication Code (HMAC) as
-defined in U.S. Federal Information Processing Standards Publication 198.
-An HMAC is a cryptographic hash that uses a key to sign a message.
-The receiver verifies the hash by recomputing it using the same key.
-
-Receivers should be careful to use Equal to compare MACs in order to avoid
-timing side-channels:
-
-	// ValidMAC reports whether messageMAC is a valid HMAC tag for message.
-	func ValidMAC(message, messageMAC, key []byte) bool {
-		mac := hmac.New(sha256.New, key)
-		mac.Write(message)
-		expectedMAC := mac.Sum(nil)
-		return hmac.Equal(messageMAC, expectedMAC)
-	}
-*/
-package hmac
-
-import (
-	"crypto/subtle"
-	"hash"
-)
-
-// FIPS 198-1:
-// https://csrc.nist.gov/publications/fips/fips198-1/FIPS-198-1_final.pdf
-
-// key is zero padded to the block size of the hash function
-// ipad = 0x36 byte repeated for key length
-// opad = 0x5c byte repeated for key length
-// hmac = H([key ^ opad] H([key ^ ipad] text))
-
-// Marshalable is the combination of encoding.BinaryMarshaler and
-// encoding.BinaryUnmarshaler. Their method definitions are repeated here to
-// avoid a dependency on the encoding package.
-type marshalable interface {
-	MarshalBinary() ([]byte, error)
-	UnmarshalBinary([]byte) error
-}
-
-type hmac struct {
-	opad, ipad   []byte
-	outer, inner hash.Hash
-
-	// If marshaled is true, then opad and ipad do not contain a padded
-	// copy of the key, but rather the marshaled state of outer/inner after
-	// opad/ipad has been fed into it.
-	marshaled bool
-}
-
-func (h *hmac) Sum(in []byte) []byte {
-	origLen := len(in)
-	in = h.inner.Sum(in)
-
-	if h.marshaled {
-		if err := h.outer.(marshalable).UnmarshalBinary(h.opad); err != nil {
-			panic(err)
-		}
-	} else {
-		h.outer.Reset()
-		h.outer.Write(h.opad)
-	}
-	h.outer.Write(in[origLen:])
-	return h.outer.Sum(in[:origLen])
-}
-
-func (h *hmac) Write(p []byte) (n int, err error) {
-	return h.inner.Write(p)
-}
-
-func (h *hmac) Size() int      { return h.outer.Size() }
-func (h *hmac) BlockSize() int { return h.inner.BlockSize() }
-
-func (h *hmac) Reset() {
-	if h.marshaled {
-		if err := h.inner.(marshalable).UnmarshalBinary(h.ipad); err != nil {
-			panic(err)
-		}
-		return
-	}
-
-	h.inner.Reset()
-	h.inner.Write(h.ipad)
-
-	// If the underlying hash is marshalable, we can save some time by
-	// saving a copy of the hash state now, and restoring it on future
-	// calls to Reset and Sum instead of writing ipad/opad every time.
-	//
-	// If either hash is unmarshalable for whatever reason,
-	// it's safe to bail out here.
-	marshalableInner, innerOK := h.inner.(marshalable)
-	if !innerOK {
-		return
-	}
-	marshalableOuter, outerOK := h.outer.(marshalable)
-	if !outerOK {
-		return
-	}
-
-	imarshal, err := marshalableInner.MarshalBinary()
-	if err != nil {
-		return
-	}
-
-	h.outer.Reset()
-	h.outer.Write(h.opad)
-	omarshal, err := marshalableOuter.MarshalBinary()
-	if err != nil {
-		return
-	}
-
-	// Marshaling succeeded; save the marshaled state for later
-	h.ipad = imarshal
-	h.opad = omarshal
-	h.marshaled = true
-}
-
-// New returns a new HMAC hash using the given hash.Hash type and key.
-// New functions like sha256.New from crypto/sha256 can be used as h.
-// h must return a new Hash every time it is called.
-// Note that unlike other hash implementations in the standard library,
-// the returned Hash does not implement encoding.BinaryMarshaler
-// or encoding.BinaryUnmarshaler.
-func New(h func() hash.Hash, key []byte) hash.Hash {
-	hm := new(hmac)
-	hm.outer = h()
-	hm.inner = h()
-	unique := true
-	func() {
-		defer func() {
-			// The comparison might panic if the underlying types are not comparable.
-			_ = recover()
-		}()
-		if hm.outer == hm.inner {
-			unique = false
-		}
-	}()
-	if !unique {
-		panic("crypto/hmac: hash generation function does not produce unique values")
-	}
-	blocksize := hm.inner.BlockSize()
-	hm.ipad = make([]byte, blocksize)
-	hm.opad = make([]byte, blocksize)
-	if len(key) > blocksize {
-		// If key is too big, hash it.
-		hm.outer.Write(key)
-		key = hm.outer.Sum(nil)
-	}
-	copy(hm.ipad, key)
-	copy(hm.opad, key)
-	for i := range hm.ipad {
-		hm.ipad[i] ^= 0x36
-	}
-	for i := range hm.opad {
-		hm.opad[i] ^= 0x5c
-	}
-	hm.inner.Write(hm.ipad)
-
-	return hm
-}
-
-// Equal compares two MACs for equality without leaking timing information.
-func Equal(mac1, mac2 []byte) bool {
-	// We don't have to be constant time if the lengths of the MACs are
-	// different as that suggests that a completely different hash function
-	// was used.
-	return subtle.ConstantTimeCompare(mac1, mac2) == 1
-}
diff --git a/contrib/go/_std_1.18/src/crypto/rand/eagain.go b/contrib/go/_std_1.18/src/crypto/rand/eagain.go
deleted file mode 100644
index f018e75931..0000000000
--- a/contrib/go/_std_1.18/src/crypto/rand/eagain.go
+++ /dev/null
@@ -1,27 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
-
-package rand
-
-import (
-	"io/fs"
-	"syscall"
-)
-
-func init() {
-	isEAGAIN = unixIsEAGAIN
-}
-
-// unixIsEAGAIN reports whether err is a syscall.EAGAIN wrapped in a PathError.
-// See golang.org/issue/9205
-func unixIsEAGAIN(err error) bool {
-	if pe, ok := err.(*fs.PathError); ok {
-		if errno, ok := pe.Err.(syscall.Errno); ok && errno == syscall.EAGAIN {
-			return true
-		}
-	}
-	return false
-}
diff --git a/contrib/go/_std_1.18/src/crypto/rand/rand_batched.go b/contrib/go/_std_1.18/src/crypto/rand/rand_batched.go
deleted file mode 100644
index c267f6a31a..0000000000
--- a/contrib/go/_std_1.18/src/crypto/rand/rand_batched.go
+++ /dev/null
@@ -1,32 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build linux || freebsd || dragonfly || solaris
-
-package rand
-
-import (
-	"errors"
-	"internal/syscall/unix"
-)
-
-// maxGetRandomRead is platform dependent.
-func init() {
-	altGetRandom = batched(getRandomBatch, maxGetRandomRead)
-}
-
-// If the kernel is too old to support the getrandom syscall(),
-// unix.GetRandom will immediately return ENOSYS and we will then fall back to
-// reading from /dev/urandom in rand_unix.go. unix.GetRandom caches the ENOSYS
-// result so we only suffer the syscall overhead once in this case.
-// If the kernel supports the getrandom() syscall, unix.GetRandom will block
-// until the kernel has sufficient randomness (as we don't use GRND_NONBLOCK).
-// In this case, unix.GetRandom will not return an error.
-func getRandomBatch(p []byte) (err error) {
-	n, err := unix.GetRandom(p, 0)
-	if n != len(p) {
-		return errors.New("short read")
-	}
-	return err
-}
diff --git a/contrib/go/_std_1.18/src/crypto/rand/rand_getentropy.go b/contrib/go/_std_1.18/src/crypto/rand/rand_getentropy.go
deleted file mode 100644
index d9e551097f..0000000000
--- a/contrib/go/_std_1.18/src/crypto/rand/rand_getentropy.go
+++ /dev/null
@@ -1,30 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build (darwin && !ios) || openbsd
-
-package rand
-
-import (
-	"internal/syscall/unix"
-)
-
-func init() {
-	altGetRandom = getEntropy
-}
-
-func getEntropy(p []byte) error {
-	// getentropy(2) returns a maximum of 256 bytes per call
-	for i := 0; i < len(p); i += 256 {
-		end := i + 256
-		if len(p) < end {
-			end = len(p)
-		}
-		err := unix.GetEntropy(p[i:end])
-		if err != nil {
-			return err
-		}
-	}
-	return nil
-}
diff --git a/contrib/go/_std_1.18/src/crypto/rand/rand_linux.go b/contrib/go/_std_1.18/src/crypto/rand/rand_linux.go
deleted file mode 100644
index 26b93c54d2..0000000000
--- a/contrib/go/_std_1.18/src/crypto/rand/rand_linux.go
+++ /dev/null
@@ -1,14 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package rand
-
-// maxGetRandomRead is the maximum number of bytes to ask for in one call to the
-// getrandom() syscall. In linux at most 2^25-1 bytes will be returned per call.
-// From the manpage
-//
-//	*  When reading from the urandom source, a maximum of 33554431 bytes
-//	   is returned by a single call to getrandom() on systems where int
-//	   has a size of 32 bits.
-const maxGetRandomRead = (1 << 25) - 1
diff --git a/contrib/go/_std_1.18/src/crypto/rand/rand_unix.go b/contrib/go/_std_1.18/src/crypto/rand/rand_unix.go
deleted file mode 100644
index 811c65f0e9..0000000000
--- a/contrib/go/_std_1.18/src/crypto/rand/rand_unix.go
+++ /dev/null
@@ -1,169 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || plan9 || solaris
-
-// Unix cryptographically secure pseudorandom number
-// generator.
-
-package rand
-
-import (
-	"bufio"
-	"crypto/aes"
-	"crypto/cipher"
-	"encoding/binary"
-	"io"
-	"os"
-	"runtime"
-	"sync"
-	"sync/atomic"
-	"time"
-)
-
-const urandomDevice = "/dev/urandom"
-
-// Easy implementation: read from /dev/urandom.
-// This is sufficient on Linux, OS X, and FreeBSD.
-
-func init() {
-	if runtime.GOOS == "plan9" {
-		Reader = newReader(nil)
-	} else {
-		Reader = &devReader{name: urandomDevice}
-	}
-}
-
-// A devReader satisfies reads by reading the file named name.
-type devReader struct {
-	name string
-	f    io.Reader
-	mu   sync.Mutex
-	used int32 // atomic; whether this devReader has been used
-}
-
-// altGetRandom if non-nil specifies an OS-specific function to get
-// urandom-style randomness.
-var altGetRandom func([]byte) (err error)
-
-func warnBlocked() {
-	println("crypto/rand: blocked for 60 seconds waiting to read random data from the kernel")
-}
-
-func (r *devReader) Read(b []byte) (n int, err error) {
-	if atomic.CompareAndSwapInt32(&r.used, 0, 1) {
-		// First use of randomness. Start timer to warn about
-		// being blocked on entropy not being available.
-		t := time.AfterFunc(60*time.Second, warnBlocked)
-		defer t.Stop()
-	}
-	if altGetRandom != nil && r.name == urandomDevice && altGetRandom(b) == nil {
-		return len(b), nil
-	}
-	r.mu.Lock()
-	defer r.mu.Unlock()
-	if r.f == nil {
-		f, err := os.Open(r.name)
-		if f == nil {
-			return 0, err
-		}
-		if runtime.GOOS == "plan9" {
-			r.f = f
-		} else {
-			r.f = bufio.NewReader(hideAgainReader{f})
-		}
-	}
-	return r.f.Read(b)
-}
-
-var isEAGAIN func(error) bool // set by eagain.go on unix systems
-
-// hideAgainReader masks EAGAIN reads from /dev/urandom.
-// See golang.org/issue/9205
-type hideAgainReader struct {
-	r io.Reader
-}
-
-func (hr hideAgainReader) Read(p []byte) (n int, err error) {
-	n, err = hr.r.Read(p)
-	if err != nil && isEAGAIN != nil && isEAGAIN(err) {
-		err = nil
-	}
-	return
-}
-
-// Alternate pseudo-random implementation for use on
-// systems without a reliable /dev/urandom.
-
-// newReader returns a new pseudorandom generator that
-// seeds itself by reading from entropy. If entropy == nil,
-// the generator seeds itself by reading from the system's
-// random number generator, typically /dev/random.
-// The Read method on the returned reader always returns
-// the full amount asked for, or else it returns an error.
-//
-// The generator uses the X9.31 algorithm with AES-128,
-// reseeding after every 1 MB of generated data.
-func newReader(entropy io.Reader) io.Reader {
-	if entropy == nil {
-		entropy = &devReader{name: "/dev/random"}
-	}
-	return &reader{entropy: entropy}
-}
-
-type reader struct {
-	mu                   sync.Mutex
-	budget               int // number of bytes that can be generated
-	cipher               cipher.Block
-	entropy              io.Reader
-	time, seed, dst, key [aes.BlockSize]byte
-}
-
-func (r *reader) Read(b []byte) (n int, err error) {
-	r.mu.Lock()
-	defer r.mu.Unlock()
-	n = len(b)
-
-	for len(b) > 0 {
-		if r.budget == 0 {
-			_, err := io.ReadFull(r.entropy, r.seed[0:])
-			if err != nil {
-				return n - len(b), err
-			}
-			_, err = io.ReadFull(r.entropy, r.key[0:])
-			if err != nil {
-				return n - len(b), err
-			}
-			r.cipher, err = aes.NewCipher(r.key[0:])
-			if err != nil {
-				return n - len(b), err
-			}
-			r.budget = 1 << 20 // reseed after generating 1MB
-		}
-		r.budget -= aes.BlockSize
-
-		// ANSI X9.31 (== X9.17) algorithm, but using AES in place of 3DES.
-		//
-		// single block:
-		// t = encrypt(time)
-		// dst = encrypt(t^seed)
-		// seed = encrypt(t^dst)
-		ns := time.Now().UnixNano()
-		binary.BigEndian.PutUint64(r.time[:], uint64(ns))
-		r.cipher.Encrypt(r.time[0:], r.time[0:])
-		for i := 0; i < aes.BlockSize; i++ {
-			r.dst[i] = r.time[i] ^ r.seed[i]
-		}
-		r.cipher.Encrypt(r.dst[0:], r.dst[0:])
-		for i := 0; i < aes.BlockSize; i++ {
-			r.seed[i] = r.time[i] ^ r.dst[i]
-		}
-		r.cipher.Encrypt(r.seed[0:], r.seed[0:])
-
-		m := copy(b, r.dst[0:])
-		b = b[m:]
-	}
-
-	return n, nil
-}
diff --git a/contrib/go/_std_1.18/src/crypto/rand/util.go b/contrib/go/_std_1.18/src/crypto/rand/util.go
deleted file mode 100644
index 4dd1711203..0000000000
--- a/contrib/go/_std_1.18/src/crypto/rand/util.go
+++ /dev/null
@@ -1,143 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package rand
-
-import (
-	"errors"
-	"io"
-	"math/big"
-)
-
-// smallPrimes is a list of small, prime numbers that allows us to rapidly
-// exclude some fraction of composite candidates when searching for a random
-// prime. This list is truncated at the point where smallPrimesProduct exceeds
-// a uint64. It does not include two because we ensure that the candidates are
-// odd by construction.
-var smallPrimes = []uint8{
-	3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53,
-}
-
-// smallPrimesProduct is the product of the values in smallPrimes and allows us
-// to reduce a candidate prime by this number and then determine whether it's
-// coprime to all the elements of smallPrimes without further big.Int
-// operations.
-var smallPrimesProduct = new(big.Int).SetUint64(16294579238595022365)
-
-// Prime returns a number, p, of the given size, such that p is prime
-// with high probability.
-// Prime will return error for any error returned by rand.Read or if bits < 2.
-func Prime(rand io.Reader, bits int) (p *big.Int, err error) {
-	if bits < 2 {
-		err = errors.New("crypto/rand: prime size must be at least 2-bit")
-		return
-	}
-
-	b := uint(bits % 8)
-	if b == 0 {
-		b = 8
-	}
-
-	bytes := make([]byte, (bits+7)/8)
-	p = new(big.Int)
-
-	bigMod := new(big.Int)
-
-	for {
-		_, err = io.ReadFull(rand, bytes)
-		if err != nil {
-			return nil, err
-		}
-
-		// Clear bits in the first byte to make sure the candidate has a size <= bits.
-		bytes[0] &= uint8(int(1<<b) - 1)
-		// Don't let the value be too small, i.e, set the most significant two bits.
-		// Setting the top two bits, rather than just the top bit,
-		// means that when two of these values are multiplied together,
-		// the result isn't ever one bit short.
-		if b >= 2 {
-			bytes[0] |= 3 << (b - 2)
-		} else {
-			// Here b==1, because b cannot be zero.
-			bytes[0] |= 1
-			if len(bytes) > 1 {
-				bytes[1] |= 0x80
-			}
-		}
-		// Make the value odd since an even number this large certainly isn't prime.
-		bytes[len(bytes)-1] |= 1
-
-		p.SetBytes(bytes)
-
-		// Calculate the value mod the product of smallPrimes. If it's
-		// a multiple of any of these primes we add two until it isn't.
-		// The probability of overflowing is minimal and can be ignored
-		// because we still perform Miller-Rabin tests on the result.
-		bigMod.Mod(p, smallPrimesProduct)
-		mod := bigMod.Uint64()
-
-	NextDelta:
-		for delta := uint64(0); delta < 1<<20; delta += 2 {
-			m := mod + delta
-			for _, prime := range smallPrimes {
-				if m%uint64(prime) == 0 && (bits > 6 || m != uint64(prime)) {
-					continue NextDelta
-				}
-			}
-
-			if delta > 0 {
-				bigMod.SetUint64(delta)
-				p.Add(p, bigMod)
-			}
-			break
-		}
-
-		// There is a tiny possibility that, by adding delta, we caused
-		// the number to be one bit too long. Thus we check BitLen
-		// here.
-		if p.ProbablyPrime(20) && p.BitLen() == bits {
-			return
-		}
-	}
-}
-
-// Int returns a uniform random value in [0, max). It panics if max <= 0.
-func Int(rand io.Reader, max *big.Int) (n *big.Int, err error) {
-	if max.Sign() <= 0 {
-		panic("crypto/rand: argument to Int is <= 0")
-	}
-	n = new(big.Int)
-	n.Sub(max, n.SetUint64(1))
-	// bitLen is the maximum bit length needed to encode a value < max.
-	bitLen := n.BitLen()
-	if bitLen == 0 {
-		// the only valid result is 0
-		return
-	}
-	// k is the maximum byte length needed to encode a value < max.
-	k := (bitLen + 7) / 8
-	// b is the number of bits in the most significant byte of max-1.
-	b := uint(bitLen % 8)
-	if b == 0 {
-		b = 8
-	}
-
-	bytes := make([]byte, k)
-
-	for {
-		_, err = io.ReadFull(rand, bytes)
-		if err != nil {
-			return nil, err
-		}
-
-		// Clear bits in the first byte to increase the probability
-		// that the candidate is < max.
-		bytes[0] &= uint8(int(1<<b) - 1)
-
-		n.SetBytes(bytes)
-		if n.Cmp(max) < 0 {
-			return
-		}
-	}
-}
diff --git a/contrib/go/_std_1.18/src/crypto/rsa/pkcs1v15.go b/contrib/go/_std_1.18/src/crypto/rsa/pkcs1v15.go
deleted file mode 100644
index 0cbd6d0045..0000000000
--- a/contrib/go/_std_1.18/src/crypto/rsa/pkcs1v15.go
+++ /dev/null
@@ -1,323 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package rsa
-
-import (
-	"crypto"
-	"crypto/subtle"
-	"errors"
-	"io"
-	"math/big"
-
-	"crypto/internal/randutil"
-)
-
-// This file implements encryption and decryption using PKCS #1 v1.5 padding.
-
-// PKCS1v15DecrypterOpts is for passing options to PKCS #1 v1.5 decryption using
-// the crypto.Decrypter interface.
-type PKCS1v15DecryptOptions struct {
-	// SessionKeyLen is the length of the session key that is being
-	// decrypted. If not zero, then a padding error during decryption will
-	// cause a random plaintext of this length to be returned rather than
-	// an error. These alternatives happen in constant time.
-	SessionKeyLen int
-}
-
-// EncryptPKCS1v15 encrypts the given message with RSA and the padding
-// scheme from PKCS #1 v1.5.  The message must be no longer than the
-// length of the public modulus minus 11 bytes.
-//
-// The rand parameter is used as a source of entropy to ensure that
-// encrypting the same message twice doesn't result in the same
-// ciphertext.
-//
-// WARNING: use of this function to encrypt plaintexts other than
-// session keys is dangerous. Use RSA OAEP in new protocols.
-func EncryptPKCS1v15(rand io.Reader, pub *PublicKey, msg []byte) ([]byte, error) {
-	randutil.MaybeReadByte(rand)
-
-	if err := checkPub(pub); err != nil {
-		return nil, err
-	}
-	k := pub.Size()
-	if len(msg) > k-11 {
-		return nil, ErrMessageTooLong
-	}
-
-	// EM = 0x00 || 0x02 || PS || 0x00 || M
-	em := make([]byte, k)
-	em[1] = 2
-	ps, mm := em[2:len(em)-len(msg)-1], em[len(em)-len(msg):]
-	err := nonZeroRandomBytes(ps, rand)
-	if err != nil {
-		return nil, err
-	}
-	em[len(em)-len(msg)-1] = 0
-	copy(mm, msg)
-
-	m := new(big.Int).SetBytes(em)
-	c := encrypt(new(big.Int), pub, m)
-
-	return c.FillBytes(em), nil
-}
-
-// DecryptPKCS1v15 decrypts a plaintext using RSA and the padding scheme from PKCS #1 v1.5.
-// If rand != nil, it uses RSA blinding to avoid timing side-channel attacks.
-//
-// Note that whether this function returns an error or not discloses secret
-// information. If an attacker can cause this function to run repeatedly and
-// learn whether each instance returned an error then they can decrypt and
-// forge signatures as if they had the private key. See
-// DecryptPKCS1v15SessionKey for a way of solving this problem.
-func DecryptPKCS1v15(rand io.Reader, priv *PrivateKey, ciphertext []byte) ([]byte, error) {
-	if err := checkPub(&priv.PublicKey); err != nil {
-		return nil, err
-	}
-	valid, out, index, err := decryptPKCS1v15(rand, priv, ciphertext)
-	if err != nil {
-		return nil, err
-	}
-	if valid == 0 {
-		return nil, ErrDecryption
-	}
-	return out[index:], nil
-}
-
-// DecryptPKCS1v15SessionKey decrypts a session key using RSA and the padding scheme from PKCS #1 v1.5.
-// If rand != nil, it uses RSA blinding to avoid timing side-channel attacks.
-// It returns an error if the ciphertext is the wrong length or if the
-// ciphertext is greater than the public modulus. Otherwise, no error is
-// returned. If the padding is valid, the resulting plaintext message is copied
-// into key. Otherwise, key is unchanged. These alternatives occur in constant
-// time. It is intended that the user of this function generate a random
-// session key beforehand and continue the protocol with the resulting value.
-// This will remove any possibility that an attacker can learn any information
-// about the plaintext.
-// See ``Chosen Ciphertext Attacks Against Protocols Based on the RSA
-// Encryption Standard PKCS #1'', Daniel Bleichenbacher, Advances in Cryptology
-// (Crypto '98).
-//
-// Note that if the session key is too small then it may be possible for an
-// attacker to brute-force it. If they can do that then they can learn whether
-// a random value was used (because it'll be different for the same ciphertext)
-// and thus whether the padding was correct. This defeats the point of this
-// function. Using at least a 16-byte key will protect against this attack.
-func DecryptPKCS1v15SessionKey(rand io.Reader, priv *PrivateKey, ciphertext []byte, key []byte) error {
-	if err := checkPub(&priv.PublicKey); err != nil {
-		return err
-	}
-	k := priv.Size()
-	if k-(len(key)+3+8) < 0 {
-		return ErrDecryption
-	}
-
-	valid, em, index, err := decryptPKCS1v15(rand, priv, ciphertext)
-	if err != nil {
-		return err
-	}
-
-	if len(em) != k {
-		// This should be impossible because decryptPKCS1v15 always
-		// returns the full slice.
-		return ErrDecryption
-	}
-
-	valid &= subtle.ConstantTimeEq(int32(len(em)-index), int32(len(key)))
-	subtle.ConstantTimeCopy(valid, key, em[len(em)-len(key):])
-	return nil
-}
-
-// decryptPKCS1v15 decrypts ciphertext using priv and blinds the operation if
-// rand is not nil. It returns one or zero in valid that indicates whether the
-// plaintext was correctly structured. In either case, the plaintext is
-// returned in em so that it may be read independently of whether it was valid
-// in order to maintain constant memory access patterns. If the plaintext was
-// valid then index contains the index of the original message in em.
-func decryptPKCS1v15(rand io.Reader, priv *PrivateKey, ciphertext []byte) (valid int, em []byte, index int, err error) {
-	k := priv.Size()
-	if k < 11 {
-		err = ErrDecryption
-		return
-	}
-
-	c := new(big.Int).SetBytes(ciphertext)
-	m, err := decrypt(rand, priv, c)
-	if err != nil {
-		return
-	}
-
-	em = m.FillBytes(make([]byte, k))
-	firstByteIsZero := subtle.ConstantTimeByteEq(em[0], 0)
-	secondByteIsTwo := subtle.ConstantTimeByteEq(em[1], 2)
-
-	// The remainder of the plaintext must be a string of non-zero random
-	// octets, followed by a 0, followed by the message.
-	//   lookingForIndex: 1 iff we are still looking for the zero.
-	//   index: the offset of the first zero byte.
-	lookingForIndex := 1
-
-	for i := 2; i < len(em); i++ {
-		equals0 := subtle.ConstantTimeByteEq(em[i], 0)
-		index = subtle.ConstantTimeSelect(lookingForIndex&equals0, i, index)
-		lookingForIndex = subtle.ConstantTimeSelect(equals0, 0, lookingForIndex)
-	}
-
-	// The PS padding must be at least 8 bytes long, and it starts two
-	// bytes into em.
-	validPS := subtle.ConstantTimeLessOrEq(2+8, index)
-
-	valid = firstByteIsZero & secondByteIsTwo & (^lookingForIndex & 1) & validPS
-	index = subtle.ConstantTimeSelect(valid, index+1, 0)
-	return valid, em, index, nil
-}
-
-// nonZeroRandomBytes fills the given slice with non-zero random octets.
-func nonZeroRandomBytes(s []byte, rand io.Reader) (err error) {
-	_, err = io.ReadFull(rand, s)
-	if err != nil {
-		return
-	}
-
-	for i := 0; i < len(s); i++ {
-		for s[i] == 0 {
-			_, err = io.ReadFull(rand, s[i:i+1])
-			if err != nil {
-				return
-			}
-			// In tests, the PRNG may return all zeros so we do
-			// this to break the loop.
-			s[i] ^= 0x42
-		}
-	}
-
-	return
-}
-
-// These are ASN1 DER structures:
-//   DigestInfo ::= SEQUENCE {
-//     digestAlgorithm AlgorithmIdentifier,
-//     digest OCTET STRING
-//   }
-// For performance, we don't use the generic ASN1 encoder. Rather, we
-// precompute a prefix of the digest value that makes a valid ASN1 DER string
-// with the correct contents.
-var hashPrefixes = map[crypto.Hash][]byte{
-	crypto.MD5:       {0x30, 0x20, 0x30, 0x0c, 0x06, 0x08, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x02, 0x05, 0x05, 0x00, 0x04, 0x10},
-	crypto.SHA1:      {0x30, 0x21, 0x30, 0x09, 0x06, 0x05, 0x2b, 0x0e, 0x03, 0x02, 0x1a, 0x05, 0x00, 0x04, 0x14},
-	crypto.SHA224:    {0x30, 0x2d, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x04, 0x05, 0x00, 0x04, 0x1c},
-	crypto.SHA256:    {0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, 0x05, 0x00, 0x04, 0x20},
-	crypto.SHA384:    {0x30, 0x41, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x02, 0x05, 0x00, 0x04, 0x30},
-	crypto.SHA512:    {0x30, 0x51, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03, 0x05, 0x00, 0x04, 0x40},
-	crypto.MD5SHA1:   {}, // A special TLS case which doesn't use an ASN1 prefix.
-	crypto.RIPEMD160: {0x30, 0x20, 0x30, 0x08, 0x06, 0x06, 0x28, 0xcf, 0x06, 0x03, 0x00, 0x31, 0x04, 0x14},
-}
-
-// SignPKCS1v15 calculates the signature of hashed using
-// RSASSA-PKCS1-V1_5-SIGN from RSA PKCS #1 v1.5.  Note that hashed must
-// be the result of hashing the input message using the given hash
-// function. If hash is zero, hashed is signed directly. This isn't
-// advisable except for interoperability.
-//
-// If rand is not nil then RSA blinding will be used to avoid timing
-// side-channel attacks.
-//
-// This function is deterministic. Thus, if the set of possible
-// messages is small, an attacker may be able to build a map from
-// messages to signatures and identify the signed messages. As ever,
-// signatures provide authenticity, not confidentiality.
-func SignPKCS1v15(rand io.Reader, priv *PrivateKey, hash crypto.Hash, hashed []byte) ([]byte, error) {
-	hashLen, prefix, err := pkcs1v15HashInfo(hash, len(hashed))
-	if err != nil {
-		return nil, err
-	}
-
-	tLen := len(prefix) + hashLen
-	k := priv.Size()
-	if k < tLen+11 {
-		return nil, ErrMessageTooLong
-	}
-
-	// EM = 0x00 || 0x01 || PS || 0x00 || T
-	em := make([]byte, k)
-	em[1] = 1
-	for i := 2; i < k-tLen-1; i++ {
-		em[i] = 0xff
-	}
-	copy(em[k-tLen:k-hashLen], prefix)
-	copy(em[k-hashLen:k], hashed)
-
-	m := new(big.Int).SetBytes(em)
-	c, err := decryptAndCheck(rand, priv, m)
-	if err != nil {
-		return nil, err
-	}
-
-	return c.FillBytes(em), nil
-}
-
-// VerifyPKCS1v15 verifies an RSA PKCS #1 v1.5 signature.
-// hashed is the result of hashing the input message using the given hash
-// function and sig is the signature. A valid signature is indicated by
-// returning a nil error. If hash is zero then hashed is used directly. This
-// isn't advisable except for interoperability.
-func VerifyPKCS1v15(pub *PublicKey, hash crypto.Hash, hashed []byte, sig []byte) error {
-	hashLen, prefix, err := pkcs1v15HashInfo(hash, len(hashed))
-	if err != nil {
-		return err
-	}
-
-	tLen := len(prefix) + hashLen
-	k := pub.Size()
-	if k < tLen+11 {
-		return ErrVerification
-	}
-
-	// RFC 8017 Section 8.2.2: If the length of the signature S is not k
-	// octets (where k is the length in octets of the RSA modulus n), output
-	// "invalid signature" and stop.
-	if k != len(sig) {
-		return ErrVerification
-	}
-
-	c := new(big.Int).SetBytes(sig)
-	m := encrypt(new(big.Int), pub, c)
-	em := m.FillBytes(make([]byte, k))
-	// EM = 0x00 || 0x01 || PS || 0x00 || T
-
-	ok := subtle.ConstantTimeByteEq(em[0], 0)
-	ok &= subtle.ConstantTimeByteEq(em[1], 1)
-	ok &= subtle.ConstantTimeCompare(em[k-hashLen:k], hashed)
-	ok &= subtle.ConstantTimeCompare(em[k-tLen:k-hashLen], prefix)
-	ok &= subtle.ConstantTimeByteEq(em[k-tLen-1], 0)
-
-	for i := 2; i < k-tLen-1; i++ {
-		ok &= subtle.ConstantTimeByteEq(em[i], 0xff)
-	}
-
-	if ok != 1 {
-		return ErrVerification
-	}
-
-	return nil
-}
-
-func pkcs1v15HashInfo(hash crypto.Hash, inLen int) (hashLen int, prefix []byte, err error) {
-	// Special case: crypto.Hash(0) is used to indicate that the data is
-	// signed directly.
-	if hash == 0 {
-		return inLen, nil, nil
-	}
-
-	hashLen = hash.Size()
-	if inLen != hashLen {
-		return 0, nil, errors.New("crypto/rsa: input must be hashed message")
-	}
-	prefix, ok := hashPrefixes[hash]
-	if !ok {
-		return 0, nil, errors.New("crypto/rsa: unsupported hash function")
-	}
-	return
-}
diff --git a/contrib/go/_std_1.18/src/crypto/rsa/pss.go b/contrib/go/_std_1.18/src/crypto/rsa/pss.go
deleted file mode 100644
index 814522de81..0000000000
--- a/contrib/go/_std_1.18/src/crypto/rsa/pss.go
+++ /dev/null
@@ -1,303 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package rsa
-
-// This file implements the RSASSA-PSS signature scheme according to RFC 8017.
-
-import (
-	"bytes"
-	"crypto"
-	"errors"
-	"hash"
-	"io"
-	"math/big"
-)
-
-// Per RFC 8017, Section 9.1
-//
-//     EM = MGF1 xor DB || H( 8*0x00 || mHash || salt ) || 0xbc
-//
-// where
-//
-//     DB = PS || 0x01 || salt
-//
-// and PS can be empty so
-//
-//     emLen = dbLen + hLen + 1 = psLen + sLen + hLen + 2
-//
-
-func emsaPSSEncode(mHash []byte, emBits int, salt []byte, hash hash.Hash) ([]byte, error) {
-	// See RFC 8017, Section 9.1.1.
-
-	hLen := hash.Size()
-	sLen := len(salt)
-	emLen := (emBits + 7) / 8
-
-	// 1.  If the length of M is greater than the input limitation for the
-	//     hash function (2^61 - 1 octets for SHA-1), output "message too
-	//     long" and stop.
-	//
-	// 2.  Let mHash = Hash(M), an octet string of length hLen.
-
-	if len(mHash) != hLen {
-		return nil, errors.New("crypto/rsa: input must be hashed with given hash")
-	}
-
-	// 3.  If emLen < hLen + sLen + 2, output "encoding error" and stop.
-
-	if emLen < hLen+sLen+2 {
-		return nil, errors.New("crypto/rsa: key size too small for PSS signature")
-	}
-
-	em := make([]byte, emLen)
-	psLen := emLen - sLen - hLen - 2
-	db := em[:psLen+1+sLen]
-	h := em[psLen+1+sLen : emLen-1]
-
-	// 4.  Generate a random octet string salt of length sLen; if sLen = 0,
-	//     then salt is the empty string.
-	//
-	// 5.  Let
-	//       M' = (0x)00 00 00 00 00 00 00 00 || mHash || salt;
-	//
-	//     M' is an octet string of length 8 + hLen + sLen with eight
-	//     initial zero octets.
-	//
-	// 6.  Let H = Hash(M'), an octet string of length hLen.
-
-	var prefix [8]byte
-
-	hash.Write(prefix[:])
-	hash.Write(mHash)
-	hash.Write(salt)
-
-	h = hash.Sum(h[:0])
-	hash.Reset()
-
-	// 7.  Generate an octet string PS consisting of emLen - sLen - hLen - 2
-	//     zero octets. The length of PS may be 0.
-	//
-	// 8.  Let DB = PS || 0x01 || salt; DB is an octet string of length
-	//     emLen - hLen - 1.
-
-	db[psLen] = 0x01
-	copy(db[psLen+1:], salt)
-
-	// 9.  Let dbMask = MGF(H, emLen - hLen - 1).
-	//
-	// 10. Let maskedDB = DB \xor dbMask.
-
-	mgf1XOR(db, hash, h)
-
-	// 11. Set the leftmost 8 * emLen - emBits bits of the leftmost octet in
-	//     maskedDB to zero.
-
-	db[0] &= 0xff >> (8*emLen - emBits)
-
-	// 12. Let EM = maskedDB || H || 0xbc.
-	em[emLen-1] = 0xbc
-
-	// 13. Output EM.
-	return em, nil
-}
-
-func emsaPSSVerify(mHash, em []byte, emBits, sLen int, hash hash.Hash) error {
-	// See RFC 8017, Section 9.1.2.
-
-	hLen := hash.Size()
-	if sLen == PSSSaltLengthEqualsHash {
-		sLen = hLen
-	}
-	emLen := (emBits + 7) / 8
-	if emLen != len(em) {
-		return errors.New("rsa: internal error: inconsistent length")
-	}
-
-	// 1.  If the length of M is greater than the input limitation for the
-	//     hash function (2^61 - 1 octets for SHA-1), output "inconsistent"
-	//     and stop.
-	//
-	// 2.  Let mHash = Hash(M), an octet string of length hLen.
-	if hLen != len(mHash) {
-		return ErrVerification
-	}
-
-	// 3.  If emLen < hLen + sLen + 2, output "inconsistent" and stop.
-	if emLen < hLen+sLen+2 {
-		return ErrVerification
-	}
-
-	// 4.  If the rightmost octet of EM does not have hexadecimal value
-	//     0xbc, output "inconsistent" and stop.
-	if em[emLen-1] != 0xbc {
-		return ErrVerification
-	}
-
-	// 5.  Let maskedDB be the leftmost emLen - hLen - 1 octets of EM, and
-	//     let H be the next hLen octets.
-	db := em[:emLen-hLen-1]
-	h := em[emLen-hLen-1 : emLen-1]
-
-	// 6.  If the leftmost 8 * emLen - emBits bits of the leftmost octet in
-	//     maskedDB are not all equal to zero, output "inconsistent" and
-	//     stop.
-	var bitMask byte = 0xff >> (8*emLen - emBits)
-	if em[0] & ^bitMask != 0 {
-		return ErrVerification
-	}
-
-	// 7.  Let dbMask = MGF(H, emLen - hLen - 1).
-	//
-	// 8.  Let DB = maskedDB \xor dbMask.
-	mgf1XOR(db, hash, h)
-
-	// 9.  Set the leftmost 8 * emLen - emBits bits of the leftmost octet in DB
-	//     to zero.
-	db[0] &= bitMask
-
-	// If we don't know the salt length, look for the 0x01 delimiter.
-	if sLen == PSSSaltLengthAuto {
-		psLen := bytes.IndexByte(db, 0x01)
-		if psLen < 0 {
-			return ErrVerification
-		}
-		sLen = len(db) - psLen - 1
-	}
-
-	// 10. If the emLen - hLen - sLen - 2 leftmost octets of DB are not zero
-	//     or if the octet at position emLen - hLen - sLen - 1 (the leftmost
-	//     position is "position 1") does not have hexadecimal value 0x01,
-	//     output "inconsistent" and stop.
-	psLen := emLen - hLen - sLen - 2
-	for _, e := range db[:psLen] {
-		if e != 0x00 {
-			return ErrVerification
-		}
-	}
-	if db[psLen] != 0x01 {
-		return ErrVerification
-	}
-
-	// 11.  Let salt be the last sLen octets of DB.
-	salt := db[len(db)-sLen:]
-
-	// 12.  Let
-	//          M' = (0x)00 00 00 00 00 00 00 00 || mHash || salt ;
-	//     M' is an octet string of length 8 + hLen + sLen with eight
-	//     initial zero octets.
-	//
-	// 13. Let H' = Hash(M'), an octet string of length hLen.
-	var prefix [8]byte
-	hash.Write(prefix[:])
-	hash.Write(mHash)
-	hash.Write(salt)
-
-	h0 := hash.Sum(nil)
-
-	// 14. If H = H', output "consistent." Otherwise, output "inconsistent."
-	if !bytes.Equal(h0, h) { // TODO: constant time?
-		return ErrVerification
-	}
-	return nil
-}
-
-// signPSSWithSalt calculates the signature of hashed using PSS with specified salt.
-// Note that hashed must be the result of hashing the input message using the
-// given hash function. salt is a random sequence of bytes whose length will be
-// later used to verify the signature.
-func signPSSWithSalt(rand io.Reader, priv *PrivateKey, hash crypto.Hash, hashed, salt []byte) ([]byte, error) {
-	emBits := priv.N.BitLen() - 1
-	em, err := emsaPSSEncode(hashed, emBits, salt, hash.New())
-	if err != nil {
-		return nil, err
-	}
-	m := new(big.Int).SetBytes(em)
-	c, err := decryptAndCheck(rand, priv, m)
-	if err != nil {
-		return nil, err
-	}
-	s := make([]byte, priv.Size())
-	return c.FillBytes(s), nil
-}
-
-const (
-	// PSSSaltLengthAuto causes the salt in a PSS signature to be as large
-	// as possible when signing, and to be auto-detected when verifying.
-	PSSSaltLengthAuto = 0
-	// PSSSaltLengthEqualsHash causes the salt length to equal the length
-	// of the hash used in the signature.
-	PSSSaltLengthEqualsHash = -1
-)
-
-// PSSOptions contains options for creating and verifying PSS signatures.
-type PSSOptions struct {
-	// SaltLength controls the length of the salt used in the PSS
-	// signature. It can either be a number of bytes, or one of the special
-	// PSSSaltLength constants.
-	SaltLength int
-
-	// Hash is the hash function used to generate the message digest. If not
-	// zero, it overrides the hash function passed to SignPSS. It's required
-	// when using PrivateKey.Sign.
-	Hash crypto.Hash
-}
-
-// HashFunc returns opts.Hash so that PSSOptions implements crypto.SignerOpts.
-func (opts *PSSOptions) HashFunc() crypto.Hash {
-	return opts.Hash
-}
-
-func (opts *PSSOptions) saltLength() int {
-	if opts == nil {
-		return PSSSaltLengthAuto
-	}
-	return opts.SaltLength
-}
-
-// SignPSS calculates the signature of digest using PSS.
-//
-// digest must be the result of hashing the input message using the given hash
-// function. The opts argument may be nil, in which case sensible defaults are
-// used. If opts.Hash is set, it overrides hash.
-func SignPSS(rand io.Reader, priv *PrivateKey, hash crypto.Hash, digest []byte, opts *PSSOptions) ([]byte, error) {
-	if opts != nil && opts.Hash != 0 {
-		hash = opts.Hash
-	}
-
-	saltLength := opts.saltLength()
-	switch saltLength {
-	case PSSSaltLengthAuto:
-		saltLength = (priv.N.BitLen()-1+7)/8 - 2 - hash.Size()
-	case PSSSaltLengthEqualsHash:
-		saltLength = hash.Size()
-	}
-
-	salt := make([]byte, saltLength)
-	if _, err := io.ReadFull(rand, salt); err != nil {
-		return nil, err
-	}
-	return signPSSWithSalt(rand, priv, hash, digest, salt)
-}
-
-// VerifyPSS verifies a PSS signature.
-//
-// A valid signature is indicated by returning a nil error. digest must be the
-// result of hashing the input message using the given hash function. The opts
-// argument may be nil, in which case sensible defaults are used. opts.Hash is
-// ignored.
-func VerifyPSS(pub *PublicKey, hash crypto.Hash, digest []byte, sig []byte, opts *PSSOptions) error {
-	if len(sig) != pub.Size() {
-		return ErrVerification
-	}
-	s := new(big.Int).SetBytes(sig)
-	m := encrypt(new(big.Int), pub, s)
-	emBits := pub.N.BitLen() - 1
-	emLen := (emBits + 7) / 8
-	if m.BitLen() > emLen*8 {
-		return ErrVerification
-	}
-	em := m.FillBytes(make([]byte, emLen))
-	return emsaPSSVerify(digest, em, emBits, opts.saltLength(), hash.New())
-}
diff --git a/contrib/go/_std_1.18/src/crypto/rsa/rsa.go b/contrib/go/_std_1.18/src/crypto/rsa/rsa.go
deleted file mode 100644
index 6fd59b3940..0000000000
--- a/contrib/go/_std_1.18/src/crypto/rsa/rsa.go
+++ /dev/null
@@ -1,659 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package rsa implements RSA encryption as specified in PKCS #1 and RFC 8017.
-//
-// RSA is a single, fundamental operation that is used in this package to
-// implement either public-key encryption or public-key signatures.
-//
-// The original specification for encryption and signatures with RSA is PKCS #1
-// and the terms "RSA encryption" and "RSA signatures" by default refer to
-// PKCS #1 version 1.5. However, that specification has flaws and new designs
-// should use version 2, usually called by just OAEP and PSS, where
-// possible.
-//
-// Two sets of interfaces are included in this package. When a more abstract
-// interface isn't necessary, there are functions for encrypting/decrypting
-// with v1.5/OAEP and signing/verifying with v1.5/PSS. If one needs to abstract
-// over the public key primitive, the PrivateKey type implements the
-// Decrypter and Signer interfaces from the crypto package.
-//
-// The RSA operations in this package are not implemented using constant-time algorithms.
-package rsa
-
-import (
-	"crypto"
-	"crypto/rand"
-	"crypto/subtle"
-	"errors"
-	"hash"
-	"io"
-	"math"
-	"math/big"
-
-	"crypto/internal/randutil"
-)
-
-var bigZero = big.NewInt(0)
-var bigOne = big.NewInt(1)
-
-// A PublicKey represents the public part of an RSA key.
-type PublicKey struct {
-	N *big.Int // modulus
-	E int      // public exponent
-}
-
-// Any methods implemented on PublicKey might need to also be implemented on
-// PrivateKey, as the latter embeds the former and will expose its methods.
-
-// Size returns the modulus size in bytes. Raw signatures and ciphertexts
-// for or by this public key will have the same size.
-func (pub *PublicKey) Size() int {
-	return (pub.N.BitLen() + 7) / 8
-}
-
-// Equal reports whether pub and x have the same value.
-func (pub *PublicKey) Equal(x crypto.PublicKey) bool {
-	xx, ok := x.(*PublicKey)
-	if !ok {
-		return false
-	}
-	return pub.N.Cmp(xx.N) == 0 && pub.E == xx.E
-}
-
-// OAEPOptions is an interface for passing options to OAEP decryption using the
-// crypto.Decrypter interface.
-type OAEPOptions struct {
-	// Hash is the hash function that will be used when generating the mask.
-	Hash crypto.Hash
-	// Label is an arbitrary byte string that must be equal to the value
-	// used when encrypting.
-	Label []byte
-}
-
-var (
-	errPublicModulus       = errors.New("crypto/rsa: missing public modulus")
-	errPublicExponentSmall = errors.New("crypto/rsa: public exponent too small")
-	errPublicExponentLarge = errors.New("crypto/rsa: public exponent too large")
-)
-
-// checkPub sanity checks the public key before we use it.
-// We require pub.E to fit into a 32-bit integer so that we
-// do not have different behavior depending on whether
-// int is 32 or 64 bits. See also
-// https://www.imperialviolet.org/2012/03/16/rsae.html.
-func checkPub(pub *PublicKey) error {
-	if pub.N == nil {
-		return errPublicModulus
-	}
-	if pub.E < 2 {
-		return errPublicExponentSmall
-	}
-	if pub.E > 1<<31-1 {
-		return errPublicExponentLarge
-	}
-	return nil
-}
-
-// A PrivateKey represents an RSA key
-type PrivateKey struct {
-	PublicKey            // public part.
-	D         *big.Int   // private exponent
-	Primes    []*big.Int // prime factors of N, has >= 2 elements.
-
-	// Precomputed contains precomputed values that speed up private
-	// operations, if available.
-	Precomputed PrecomputedValues
-}
-
-// Public returns the public key corresponding to priv.
-func (priv *PrivateKey) Public() crypto.PublicKey {
-	return &priv.PublicKey
-}
-
-// Equal reports whether priv and x have equivalent values. It ignores
-// Precomputed values.
-func (priv *PrivateKey) Equal(x crypto.PrivateKey) bool {
-	xx, ok := x.(*PrivateKey)
-	if !ok {
-		return false
-	}
-	if !priv.PublicKey.Equal(&xx.PublicKey) || priv.D.Cmp(xx.D) != 0 {
-		return false
-	}
-	if len(priv.Primes) != len(xx.Primes) {
-		return false
-	}
-	for i := range priv.Primes {
-		if priv.Primes[i].Cmp(xx.Primes[i]) != 0 {
-			return false
-		}
-	}
-	return true
-}
-
-// Sign signs digest with priv, reading randomness from rand. If opts is a
-// *PSSOptions then the PSS algorithm will be used, otherwise PKCS #1 v1.5 will
-// be used. digest must be the result of hashing the input message using
-// opts.HashFunc().
-//
-// This method implements crypto.Signer, which is an interface to support keys
-// where the private part is kept in, for example, a hardware module. Common
-// uses should use the Sign* functions in this package directly.
-func (priv *PrivateKey) Sign(rand io.Reader, digest []byte, opts crypto.SignerOpts) ([]byte, error) {
-	if pssOpts, ok := opts.(*PSSOptions); ok {
-		return SignPSS(rand, priv, pssOpts.Hash, digest, pssOpts)
-	}
-
-	return SignPKCS1v15(rand, priv, opts.HashFunc(), digest)
-}
-
-// Decrypt decrypts ciphertext with priv. If opts is nil or of type
-// *PKCS1v15DecryptOptions then PKCS #1 v1.5 decryption is performed. Otherwise
-// opts must have type *OAEPOptions and OAEP decryption is done.
-func (priv *PrivateKey) Decrypt(rand io.Reader, ciphertext []byte, opts crypto.DecrypterOpts) (plaintext []byte, err error) {
-	if opts == nil {
-		return DecryptPKCS1v15(rand, priv, ciphertext)
-	}
-
-	switch opts := opts.(type) {
-	case *OAEPOptions:
-		return DecryptOAEP(opts.Hash.New(), rand, priv, ciphertext, opts.Label)
-
-	case *PKCS1v15DecryptOptions:
-		if l := opts.SessionKeyLen; l > 0 {
-			plaintext = make([]byte, l)
-			if _, err := io.ReadFull(rand, plaintext); err != nil {
-				return nil, err
-			}
-			if err := DecryptPKCS1v15SessionKey(rand, priv, ciphertext, plaintext); err != nil {
-				return nil, err
-			}
-			return plaintext, nil
-		} else {
-			return DecryptPKCS1v15(rand, priv, ciphertext)
-		}
-
-	default:
-		return nil, errors.New("crypto/rsa: invalid options for Decrypt")
-	}
-}
-
-type PrecomputedValues struct {
-	Dp, Dq *big.Int // D mod (P-1) (or mod Q-1)
-	Qinv   *big.Int // Q^-1 mod P
-
-	// CRTValues is used for the 3rd and subsequent primes. Due to a
-	// historical accident, the CRT for the first two primes is handled
-	// differently in PKCS #1 and interoperability is sufficiently
-	// important that we mirror this.
-	CRTValues []CRTValue
-}
-
-// CRTValue contains the precomputed Chinese remainder theorem values.
-type CRTValue struct {
-	Exp   *big.Int // D mod (prime-1).
-	Coeff *big.Int // R·Coeff ≡ 1 mod Prime.
-	R     *big.Int // product of primes prior to this (inc p and q).
-}
-
-// Validate performs basic sanity checks on the key.
-// It returns nil if the key is valid, or else an error describing a problem.
-func (priv *PrivateKey) Validate() error {
-	if err := checkPub(&priv.PublicKey); err != nil {
-		return err
-	}
-
-	// Check that Πprimes == n.
-	modulus := new(big.Int).Set(bigOne)
-	for _, prime := range priv.Primes {
-		// Any primes ≤ 1 will cause divide-by-zero panics later.
-		if prime.Cmp(bigOne) <= 0 {
-			return errors.New("crypto/rsa: invalid prime value")
-		}
-		modulus.Mul(modulus, prime)
-	}
-	if modulus.Cmp(priv.N) != 0 {
-		return errors.New("crypto/rsa: invalid modulus")
-	}
-
-	// Check that de ≡ 1 mod p-1, for each prime.
-	// This implies that e is coprime to each p-1 as e has a multiplicative
-	// inverse. Therefore e is coprime to lcm(p-1,q-1,r-1,...) =
-	// exponent(ℤ/nℤ). It also implies that a^de ≡ a mod p as a^(p-1) ≡ 1
-	// mod p. Thus a^de ≡ a mod n for all a coprime to n, as required.
-	congruence := new(big.Int)
-	de := new(big.Int).SetInt64(int64(priv.E))
-	de.Mul(de, priv.D)
-	for _, prime := range priv.Primes {
-		pminus1 := new(big.Int).Sub(prime, bigOne)
-		congruence.Mod(de, pminus1)
-		if congruence.Cmp(bigOne) != 0 {
-			return errors.New("crypto/rsa: invalid exponents")
-		}
-	}
-	return nil
-}
-
-// GenerateKey generates an RSA keypair of the given bit size using the
-// random source random (for example, crypto/rand.Reader).
-func GenerateKey(random io.Reader, bits int) (*PrivateKey, error) {
-	return GenerateMultiPrimeKey(random, 2, bits)
-}
-
-// GenerateMultiPrimeKey generates a multi-prime RSA keypair of the given bit
-// size and the given random source, as suggested in [1]. Although the public
-// keys are compatible (actually, indistinguishable) from the 2-prime case,
-// the private keys are not. Thus it may not be possible to export multi-prime
-// private keys in certain formats or to subsequently import them into other
-// code.
-//
-// Table 1 in [2] suggests maximum numbers of primes for a given size.
-//
-// [1] US patent 4405829 (1972, expired)
-// [2] http://www.cacr.math.uwaterloo.ca/techreports/2006/cacr2006-16.pdf
-func GenerateMultiPrimeKey(random io.Reader, nprimes int, bits int) (*PrivateKey, error) {
-	randutil.MaybeReadByte(random)
-
-	priv := new(PrivateKey)
-	priv.E = 65537
-
-	if nprimes < 2 {
-		return nil, errors.New("crypto/rsa: GenerateMultiPrimeKey: nprimes must be >= 2")
-	}
-
-	if bits < 64 {
-		primeLimit := float64(uint64(1) << uint(bits/nprimes))
-		// pi approximates the number of primes less than primeLimit
-		pi := primeLimit / (math.Log(primeLimit) - 1)
-		// Generated primes start with 11 (in binary) so we can only
-		// use a quarter of them.
-		pi /= 4
-		// Use a factor of two to ensure that key generation terminates
-		// in a reasonable amount of time.
-		pi /= 2
-		if pi <= float64(nprimes) {
-			return nil, errors.New("crypto/rsa: too few primes of given length to generate an RSA key")
-		}
-	}
-
-	primes := make([]*big.Int, nprimes)
-
-NextSetOfPrimes:
-	for {
-		todo := bits
-		// crypto/rand should set the top two bits in each prime.
-		// Thus each prime has the form
-		//   p_i = 2^bitlen(p_i) × 0.11... (in base 2).
-		// And the product is:
-		//   P = 2^todo × α
-		// where α is the product of nprimes numbers of the form 0.11...
-		//
-		// If α < 1/2 (which can happen for nprimes > 2), we need to
-		// shift todo to compensate for lost bits: the mean value of 0.11...
-		// is 7/8, so todo + shift - nprimes * log2(7/8) ~= bits - 1/2
-		// will give good results.
-		if nprimes >= 7 {
-			todo += (nprimes - 2) / 5
-		}
-		for i := 0; i < nprimes; i++ {
-			var err error
-			primes[i], err = rand.Prime(random, todo/(nprimes-i))
-			if err != nil {
-				return nil, err
-			}
-			todo -= primes[i].BitLen()
-		}
-
-		// Make sure that primes is pairwise unequal.
-		for i, prime := range primes {
-			for j := 0; j < i; j++ {
-				if prime.Cmp(primes[j]) == 0 {
-					continue NextSetOfPrimes
-				}
-			}
-		}
-
-		n := new(big.Int).Set(bigOne)
-		totient := new(big.Int).Set(bigOne)
-		pminus1 := new(big.Int)
-		for _, prime := range primes {
-			n.Mul(n, prime)
-			pminus1.Sub(prime, bigOne)
-			totient.Mul(totient, pminus1)
-		}
-		if n.BitLen() != bits {
-			// This should never happen for nprimes == 2 because
-			// crypto/rand should set the top two bits in each prime.
-			// For nprimes > 2 we hope it does not happen often.
-			continue NextSetOfPrimes
-		}
-
-		priv.D = new(big.Int)
-		e := big.NewInt(int64(priv.E))
-		ok := priv.D.ModInverse(e, totient)
-
-		if ok != nil {
-			priv.Primes = primes
-			priv.N = n
-			break
-		}
-	}
-
-	priv.Precompute()
-	return priv, nil
-}
-
-// incCounter increments a four byte, big-endian counter.
-func incCounter(c *[4]byte) {
-	if c[3]++; c[3] != 0 {
-		return
-	}
-	if c[2]++; c[2] != 0 {
-		return
-	}
-	if c[1]++; c[1] != 0 {
-		return
-	}
-	c[0]++
-}
-
-// mgf1XOR XORs the bytes in out with a mask generated using the MGF1 function
-// specified in PKCS #1 v2.1.
-func mgf1XOR(out []byte, hash hash.Hash, seed []byte) {
-	var counter [4]byte
-	var digest []byte
-
-	done := 0
-	for done < len(out) {
-		hash.Write(seed)
-		hash.Write(counter[0:4])
-		digest = hash.Sum(digest[:0])
-		hash.Reset()
-
-		for i := 0; i < len(digest) && done < len(out); i++ {
-			out[done] ^= digest[i]
-			done++
-		}
-		incCounter(&counter)
-	}
-}
-
-// ErrMessageTooLong is returned when attempting to encrypt a message which is
-// too large for the size of the public key.
-var ErrMessageTooLong = errors.New("crypto/rsa: message too long for RSA public key size")
-
-func encrypt(c *big.Int, pub *PublicKey, m *big.Int) *big.Int {
-	e := big.NewInt(int64(pub.E))
-	c.Exp(m, e, pub.N)
-	return c
-}
-
-// EncryptOAEP encrypts the given message with RSA-OAEP.
-//
-// OAEP is parameterised by a hash function that is used as a random oracle.
-// Encryption and decryption of a given message must use the same hash function
-// and sha256.New() is a reasonable choice.
-//
-// The random parameter is used as a source of entropy to ensure that
-// encrypting the same message twice doesn't result in the same ciphertext.
-//
-// The label parameter may contain arbitrary data that will not be encrypted,
-// but which gives important context to the message. For example, if a given
-// public key is used to encrypt two types of messages then distinct label
-// values could be used to ensure that a ciphertext for one purpose cannot be
-// used for another by an attacker. If not required it can be empty.
-//
-// The message must be no longer than the length of the public modulus minus
-// twice the hash length, minus a further 2.
-func EncryptOAEP(hash hash.Hash, random io.Reader, pub *PublicKey, msg []byte, label []byte) ([]byte, error) {
-	if err := checkPub(pub); err != nil {
-		return nil, err
-	}
-	hash.Reset()
-	k := pub.Size()
-	if len(msg) > k-2*hash.Size()-2 {
-		return nil, ErrMessageTooLong
-	}
-
-	hash.Write(label)
-	lHash := hash.Sum(nil)
-	hash.Reset()
-
-	em := make([]byte, k)
-	seed := em[1 : 1+hash.Size()]
-	db := em[1+hash.Size():]
-
-	copy(db[0:hash.Size()], lHash)
-	db[len(db)-len(msg)-1] = 1
-	copy(db[len(db)-len(msg):], msg)
-
-	_, err := io.ReadFull(random, seed)
-	if err != nil {
-		return nil, err
-	}
-
-	mgf1XOR(db, hash, seed)
-	mgf1XOR(seed, hash, db)
-
-	m := new(big.Int)
-	m.SetBytes(em)
-	c := encrypt(new(big.Int), pub, m)
-
-	out := make([]byte, k)
-	return c.FillBytes(out), nil
-}
-
-// ErrDecryption represents a failure to decrypt a message.
-// It is deliberately vague to avoid adaptive attacks.
-var ErrDecryption = errors.New("crypto/rsa: decryption error")
-
-// ErrVerification represents a failure to verify a signature.
-// It is deliberately vague to avoid adaptive attacks.
-var ErrVerification = errors.New("crypto/rsa: verification error")
-
-// Precompute performs some calculations that speed up private key operations
-// in the future.
-func (priv *PrivateKey) Precompute() {
-	if priv.Precomputed.Dp != nil {
-		return
-	}
-
-	priv.Precomputed.Dp = new(big.Int).Sub(priv.Primes[0], bigOne)
-	priv.Precomputed.Dp.Mod(priv.D, priv.Precomputed.Dp)
-
-	priv.Precomputed.Dq = new(big.Int).Sub(priv.Primes[1], bigOne)
-	priv.Precomputed.Dq.Mod(priv.D, priv.Precomputed.Dq)
-
-	priv.Precomputed.Qinv = new(big.Int).ModInverse(priv.Primes[1], priv.Primes[0])
-
-	r := new(big.Int).Mul(priv.Primes[0], priv.Primes[1])
-	priv.Precomputed.CRTValues = make([]CRTValue, len(priv.Primes)-2)
-	for i := 2; i < len(priv.Primes); i++ {
-		prime := priv.Primes[i]
-		values := &priv.Precomputed.CRTValues[i-2]
-
-		values.Exp = new(big.Int).Sub(prime, bigOne)
-		values.Exp.Mod(priv.D, values.Exp)
-
-		values.R = new(big.Int).Set(r)
-		values.Coeff = new(big.Int).ModInverse(r, prime)
-
-		r.Mul(r, prime)
-	}
-}
-
-// decrypt performs an RSA decryption, resulting in a plaintext integer. If a
-// random source is given, RSA blinding is used.
-func decrypt(random io.Reader, priv *PrivateKey, c *big.Int) (m *big.Int, err error) {
-	// TODO(agl): can we get away with reusing blinds?
-	if c.Cmp(priv.N) > 0 {
-		err = ErrDecryption
-		return
-	}
-	if priv.N.Sign() == 0 {
-		return nil, ErrDecryption
-	}
-
-	var ir *big.Int
-	if random != nil {
-		randutil.MaybeReadByte(random)
-
-		// Blinding enabled. Blinding involves multiplying c by r^e.
-		// Then the decryption operation performs (m^e * r^e)^d mod n
-		// which equals mr mod n. The factor of r can then be removed
-		// by multiplying by the multiplicative inverse of r.
-
-		var r *big.Int
-		ir = new(big.Int)
-		for {
-			r, err = rand.Int(random, priv.N)
-			if err != nil {
-				return
-			}
-			if r.Cmp(bigZero) == 0 {
-				r = bigOne
-			}
-			ok := ir.ModInverse(r, priv.N)
-			if ok != nil {
-				break
-			}
-		}
-		bigE := big.NewInt(int64(priv.E))
-		rpowe := new(big.Int).Exp(r, bigE, priv.N) // N != 0
-		cCopy := new(big.Int).Set(c)
-		cCopy.Mul(cCopy, rpowe)
-		cCopy.Mod(cCopy, priv.N)
-		c = cCopy
-	}
-
-	if priv.Precomputed.Dp == nil {
-		m = new(big.Int).Exp(c, priv.D, priv.N)
-	} else {
-		// We have the precalculated values needed for the CRT.
-		m = new(big.Int).Exp(c, priv.Precomputed.Dp, priv.Primes[0])
-		m2 := new(big.Int).Exp(c, priv.Precomputed.Dq, priv.Primes[1])
-		m.Sub(m, m2)
-		if m.Sign() < 0 {
-			m.Add(m, priv.Primes[0])
-		}
-		m.Mul(m, priv.Precomputed.Qinv)
-		m.Mod(m, priv.Primes[0])
-		m.Mul(m, priv.Primes[1])
-		m.Add(m, m2)
-
-		for i, values := range priv.Precomputed.CRTValues {
-			prime := priv.Primes[2+i]
-			m2.Exp(c, values.Exp, prime)
-			m2.Sub(m2, m)
-			m2.Mul(m2, values.Coeff)
-			m2.Mod(m2, prime)
-			if m2.Sign() < 0 {
-				m2.Add(m2, prime)
-			}
-			m2.Mul(m2, values.R)
-			m.Add(m, m2)
-		}
-	}
-
-	if ir != nil {
-		// Unblind.
-		m.Mul(m, ir)
-		m.Mod(m, priv.N)
-	}
-
-	return
-}
-
-func decryptAndCheck(random io.Reader, priv *PrivateKey, c *big.Int) (m *big.Int, err error) {
-	m, err = decrypt(random, priv, c)
-	if err != nil {
-		return nil, err
-	}
-
-	// In order to defend against errors in the CRT computation, m^e is
-	// calculated, which should match the original ciphertext.
-	check := encrypt(new(big.Int), &priv.PublicKey, m)
-	if c.Cmp(check) != 0 {
-		return nil, errors.New("rsa: internal error")
-	}
-	return m, nil
-}
-
-// DecryptOAEP decrypts ciphertext using RSA-OAEP.
-//
-// OAEP is parameterised by a hash function that is used as a random oracle.
-// Encryption and decryption of a given message must use the same hash function
-// and sha256.New() is a reasonable choice.
-//
-// The random parameter, if not nil, is used to blind the private-key operation
-// and avoid timing side-channel attacks. Blinding is purely internal to this
-// function – the random data need not match that used when encrypting.
-//
-// The label parameter must match the value given when encrypting. See
-// EncryptOAEP for details.
-func DecryptOAEP(hash hash.Hash, random io.Reader, priv *PrivateKey, ciphertext []byte, label []byte) ([]byte, error) {
-	if err := checkPub(&priv.PublicKey); err != nil {
-		return nil, err
-	}
-	k := priv.Size()
-	if len(ciphertext) > k ||
-		k < hash.Size()*2+2 {
-		return nil, ErrDecryption
-	}
-
-	c := new(big.Int).SetBytes(ciphertext)
-
-	m, err := decrypt(random, priv, c)
-	if err != nil {
-		return nil, err
-	}
-
-	hash.Write(label)
-	lHash := hash.Sum(nil)
-	hash.Reset()
-
-	// We probably leak the number of leading zeros.
-	// It's not clear that we can do anything about this.
-	em := m.FillBytes(make([]byte, k))
-
-	firstByteIsZero := subtle.ConstantTimeByteEq(em[0], 0)
-
-	seed := em[1 : hash.Size()+1]
-	db := em[hash.Size()+1:]
-
-	mgf1XOR(seed, hash, db)
-	mgf1XOR(db, hash, seed)
-
-	lHash2 := db[0:hash.Size()]
-
-	// We have to validate the plaintext in constant time in order to avoid
-	// attacks like: J. Manger. A Chosen Ciphertext Attack on RSA Optimal
-	// Asymmetric Encryption Padding (OAEP) as Standardized in PKCS #1
-	// v2.0. In J. Kilian, editor, Advances in Cryptology.
-	lHash2Good := subtle.ConstantTimeCompare(lHash, lHash2)
-
-	// The remainder of the plaintext must be zero or more 0x00, followed
-	// by 0x01, followed by the message.
-	//   lookingForIndex: 1 iff we are still looking for the 0x01
-	//   index: the offset of the first 0x01 byte
-	//   invalid: 1 iff we saw a non-zero byte before the 0x01.
-	var lookingForIndex, index, invalid int
-	lookingForIndex = 1
-	rest := db[hash.Size():]
-
-	for i := 0; i < len(rest); i++ {
-		equals0 := subtle.ConstantTimeByteEq(rest[i], 0)
-		equals1 := subtle.ConstantTimeByteEq(rest[i], 1)
-		index = subtle.ConstantTimeSelect(lookingForIndex&equals1, i, index)
-		lookingForIndex = subtle.ConstantTimeSelect(equals1, 0, lookingForIndex)
-		invalid = subtle.ConstantTimeSelect(lookingForIndex&^equals0, 1, invalid)
-	}
-
-	if firstByteIsZero&lHash2Good&^invalid&^lookingForIndex != 1 {
-		return nil, ErrDecryption
-	}
-
-	return rest[index+1:], nil
-}
diff --git a/contrib/go/_std_1.18/src/crypto/sha1/sha1.go b/contrib/go/_std_1.18/src/crypto/sha1/sha1.go
deleted file mode 100644
index 286a59d33d..0000000000
--- a/contrib/go/_std_1.18/src/crypto/sha1/sha1.go
+++ /dev/null
@@ -1,266 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package sha1 implements the SHA-1 hash algorithm as defined in RFC 3174.
-//
-// SHA-1 is cryptographically broken and should not be used for secure
-// applications.
-package sha1
-
-import (
-	"crypto"
-	"encoding/binary"
-	"errors"
-	"hash"
-)
-
-func init() {
-	crypto.RegisterHash(crypto.SHA1, New)
-}
-
-// The size of a SHA-1 checksum in bytes.
-const Size = 20
-
-// The blocksize of SHA-1 in bytes.
-const BlockSize = 64
-
-const (
-	chunk = 64
-	init0 = 0x67452301
-	init1 = 0xEFCDAB89
-	init2 = 0x98BADCFE
-	init3 = 0x10325476
-	init4 = 0xC3D2E1F0
-)
-
-// digest represents the partial evaluation of a checksum.
-type digest struct {
-	h   [5]uint32
-	x   [chunk]byte
-	nx  int
-	len uint64
-}
-
-const (
-	magic         = "sha\x01"
-	marshaledSize = len(magic) + 5*4 + chunk + 8
-)
-
-func (d *digest) MarshalBinary() ([]byte, error) {
-	b := make([]byte, 0, marshaledSize)
-	b = append(b, magic...)
-	b = appendUint32(b, d.h[0])
-	b = appendUint32(b, d.h[1])
-	b = appendUint32(b, d.h[2])
-	b = appendUint32(b, d.h[3])
-	b = appendUint32(b, d.h[4])
-	b = append(b, d.x[:d.nx]...)
-	b = b[:len(b)+len(d.x)-int(d.nx)] // already zero
-	b = appendUint64(b, d.len)
-	return b, nil
-}
-
-func (d *digest) UnmarshalBinary(b []byte) error {
-	if len(b) < len(magic) || string(b[:len(magic)]) != magic {
-		return errors.New("crypto/sha1: invalid hash state identifier")
-	}
-	if len(b) != marshaledSize {
-		return errors.New("crypto/sha1: invalid hash state size")
-	}
-	b = b[len(magic):]
-	b, d.h[0] = consumeUint32(b)
-	b, d.h[1] = consumeUint32(b)
-	b, d.h[2] = consumeUint32(b)
-	b, d.h[3] = consumeUint32(b)
-	b, d.h[4] = consumeUint32(b)
-	b = b[copy(d.x[:], b):]
-	b, d.len = consumeUint64(b)
-	d.nx = int(d.len % chunk)
-	return nil
-}
-
-func appendUint64(b []byte, x uint64) []byte {
-	var a [8]byte
-	binary.BigEndian.PutUint64(a[:], x)
-	return append(b, a[:]...)
-}
-
-func appendUint32(b []byte, x uint32) []byte {
-	var a [4]byte
-	binary.BigEndian.PutUint32(a[:], x)
-	return append(b, a[:]...)
-}
-
-func consumeUint64(b []byte) ([]byte, uint64) {
-	_ = b[7]
-	x := uint64(b[7]) | uint64(b[6])<<8 | uint64(b[5])<<16 | uint64(b[4])<<24 |
-		uint64(b[3])<<32 | uint64(b[2])<<40 | uint64(b[1])<<48 | uint64(b[0])<<56
-	return b[8:], x
-}
-
-func consumeUint32(b []byte) ([]byte, uint32) {
-	_ = b[3]
-	x := uint32(b[3]) | uint32(b[2])<<8 | uint32(b[1])<<16 | uint32(b[0])<<24
-	return b[4:], x
-}
-
-func (d *digest) Reset() {
-	d.h[0] = init0
-	d.h[1] = init1
-	d.h[2] = init2
-	d.h[3] = init3
-	d.h[4] = init4
-	d.nx = 0
-	d.len = 0
-}
-
-// New returns a new hash.Hash computing the SHA1 checksum. The Hash also
-// implements encoding.BinaryMarshaler and encoding.BinaryUnmarshaler to
-// marshal and unmarshal the internal state of the hash.
-func New() hash.Hash {
-	d := new(digest)
-	d.Reset()
-	return d
-}
-
-func (d *digest) Size() int { return Size }
-
-func (d *digest) BlockSize() int { return BlockSize }
-
-func (d *digest) Write(p []byte) (nn int, err error) {
-	nn = len(p)
-	d.len += uint64(nn)
-	if d.nx > 0 {
-		n := copy(d.x[d.nx:], p)
-		d.nx += n
-		if d.nx == chunk {
-			block(d, d.x[:])
-			d.nx = 0
-		}
-		p = p[n:]
-	}
-	if len(p) >= chunk {
-		n := len(p) &^ (chunk - 1)
-		block(d, p[:n])
-		p = p[n:]
-	}
-	if len(p) > 0 {
-		d.nx = copy(d.x[:], p)
-	}
-	return
-}
-
-func (d *digest) Sum(in []byte) []byte {
-	// Make a copy of d so that caller can keep writing and summing.
-	d0 := *d
-	hash := d0.checkSum()
-	return append(in, hash[:]...)
-}
-
-func (d *digest) checkSum() [Size]byte {
-	len := d.len
-	// Padding.  Add a 1 bit and 0 bits until 56 bytes mod 64.
-	var tmp [64]byte
-	tmp[0] = 0x80
-	if len%64 < 56 {
-		d.Write(tmp[0 : 56-len%64])
-	} else {
-		d.Write(tmp[0 : 64+56-len%64])
-	}
-
-	// Length in bits.
-	len <<= 3
-	binary.BigEndian.PutUint64(tmp[:], len)
-	d.Write(tmp[0:8])
-
-	if d.nx != 0 {
-		panic("d.nx != 0")
-	}
-
-	var digest [Size]byte
-
-	binary.BigEndian.PutUint32(digest[0:], d.h[0])
-	binary.BigEndian.PutUint32(digest[4:], d.h[1])
-	binary.BigEndian.PutUint32(digest[8:], d.h[2])
-	binary.BigEndian.PutUint32(digest[12:], d.h[3])
-	binary.BigEndian.PutUint32(digest[16:], d.h[4])
-
-	return digest
-}
-
-// ConstantTimeSum computes the same result of Sum() but in constant time
-func (d *digest) ConstantTimeSum(in []byte) []byte {
-	d0 := *d
-	hash := d0.constSum()
-	return append(in, hash[:]...)
-}
-
-func (d *digest) constSum() [Size]byte {
-	var length [8]byte
-	l := d.len << 3
-	for i := uint(0); i < 8; i++ {
-		length[i] = byte(l >> (56 - 8*i))
-	}
-
-	nx := byte(d.nx)
-	t := nx - 56                 // if nx < 56 then the MSB of t is one
-	mask1b := byte(int8(t) >> 7) // mask1b is 0xFF iff one block is enough
-
-	separator := byte(0x80) // gets reset to 0x00 once used
-	for i := byte(0); i < chunk; i++ {
-		mask := byte(int8(i-nx) >> 7) // 0x00 after the end of data
-
-		// if we reached the end of the data, replace with 0x80 or 0x00
-		d.x[i] = (^mask & separator) | (mask & d.x[i])
-
-		// zero the separator once used
-		separator &= mask
-
-		if i >= 56 {
-			// we might have to write the length here if all fit in one block
-			d.x[i] |= mask1b & length[i-56]
-		}
-	}
-
-	// compress, and only keep the digest if all fit in one block
-	block(d, d.x[:])
-
-	var digest [Size]byte
-	for i, s := range d.h {
-		digest[i*4] = mask1b & byte(s>>24)
-		digest[i*4+1] = mask1b & byte(s>>16)
-		digest[i*4+2] = mask1b & byte(s>>8)
-		digest[i*4+3] = mask1b & byte(s)
-	}
-
-	for i := byte(0); i < chunk; i++ {
-		// second block, it's always past the end of data, might start with 0x80
-		if i < 56 {
-			d.x[i] = separator
-			separator = 0
-		} else {
-			d.x[i] = length[i-56]
-		}
-	}
-
-	// compress, and only keep the digest if we actually needed the second block
-	block(d, d.x[:])
-
-	for i, s := range d.h {
-		digest[i*4] |= ^mask1b & byte(s>>24)
-		digest[i*4+1] |= ^mask1b & byte(s>>16)
-		digest[i*4+2] |= ^mask1b & byte(s>>8)
-		digest[i*4+3] |= ^mask1b & byte(s)
-	}
-
-	return digest
-}
-
-// Sum returns the SHA-1 checksum of the data.
-func Sum(data []byte) [Size]byte {
-	var d digest
-	d.Reset()
-	d.Write(data)
-	return d.checkSum()
-}
diff --git a/contrib/go/_std_1.18/src/crypto/sha256/sha256.go b/contrib/go/_std_1.18/src/crypto/sha256/sha256.go
deleted file mode 100644
index 659531dc71..0000000000
--- a/contrib/go/_std_1.18/src/crypto/sha256/sha256.go
+++ /dev/null
@@ -1,270 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package sha256 implements the SHA224 and SHA256 hash algorithms as defined
-// in FIPS 180-4.
-package sha256
-
-import (
-	"crypto"
-	"encoding/binary"
-	"errors"
-	"hash"
-)
-
-func init() {
-	crypto.RegisterHash(crypto.SHA224, New224)
-	crypto.RegisterHash(crypto.SHA256, New)
-}
-
-// The size of a SHA256 checksum in bytes.
-const Size = 32
-
-// The size of a SHA224 checksum in bytes.
-const Size224 = 28
-
-// The blocksize of SHA256 and SHA224 in bytes.
-const BlockSize = 64
-
-const (
-	chunk     = 64
-	init0     = 0x6A09E667
-	init1     = 0xBB67AE85
-	init2     = 0x3C6EF372
-	init3     = 0xA54FF53A
-	init4     = 0x510E527F
-	init5     = 0x9B05688C
-	init6     = 0x1F83D9AB
-	init7     = 0x5BE0CD19
-	init0_224 = 0xC1059ED8
-	init1_224 = 0x367CD507
-	init2_224 = 0x3070DD17
-	init3_224 = 0xF70E5939
-	init4_224 = 0xFFC00B31
-	init5_224 = 0x68581511
-	init6_224 = 0x64F98FA7
-	init7_224 = 0xBEFA4FA4
-)
-
-// digest represents the partial evaluation of a checksum.
-type digest struct {
-	h     [8]uint32
-	x     [chunk]byte
-	nx    int
-	len   uint64
-	is224 bool // mark if this digest is SHA-224
-}
-
-const (
-	magic224      = "sha\x02"
-	magic256      = "sha\x03"
-	marshaledSize = len(magic256) + 8*4 + chunk + 8
-)
-
-func (d *digest) MarshalBinary() ([]byte, error) {
-	b := make([]byte, 0, marshaledSize)
-	if d.is224 {
-		b = append(b, magic224...)
-	} else {
-		b = append(b, magic256...)
-	}
-	b = appendUint32(b, d.h[0])
-	b = appendUint32(b, d.h[1])
-	b = appendUint32(b, d.h[2])
-	b = appendUint32(b, d.h[3])
-	b = appendUint32(b, d.h[4])
-	b = appendUint32(b, d.h[5])
-	b = appendUint32(b, d.h[6])
-	b = appendUint32(b, d.h[7])
-	b = append(b, d.x[:d.nx]...)
-	b = b[:len(b)+len(d.x)-int(d.nx)] // already zero
-	b = appendUint64(b, d.len)
-	return b, nil
-}
-
-func (d *digest) UnmarshalBinary(b []byte) error {
-	if len(b) < len(magic224) || (d.is224 && string(b[:len(magic224)]) != magic224) || (!d.is224 && string(b[:len(magic256)]) != magic256) {
-		return errors.New("crypto/sha256: invalid hash state identifier")
-	}
-	if len(b) != marshaledSize {
-		return errors.New("crypto/sha256: invalid hash state size")
-	}
-	b = b[len(magic224):]
-	b, d.h[0] = consumeUint32(b)
-	b, d.h[1] = consumeUint32(b)
-	b, d.h[2] = consumeUint32(b)
-	b, d.h[3] = consumeUint32(b)
-	b, d.h[4] = consumeUint32(b)
-	b, d.h[5] = consumeUint32(b)
-	b, d.h[6] = consumeUint32(b)
-	b, d.h[7] = consumeUint32(b)
-	b = b[copy(d.x[:], b):]
-	b, d.len = consumeUint64(b)
-	d.nx = int(d.len % chunk)
-	return nil
-}
-
-func appendUint64(b []byte, x uint64) []byte {
-	var a [8]byte
-	binary.BigEndian.PutUint64(a[:], x)
-	return append(b, a[:]...)
-}
-
-func appendUint32(b []byte, x uint32) []byte {
-	var a [4]byte
-	binary.BigEndian.PutUint32(a[:], x)
-	return append(b, a[:]...)
-}
-
-func consumeUint64(b []byte) ([]byte, uint64) {
-	_ = b[7]
-	x := uint64(b[7]) | uint64(b[6])<<8 | uint64(b[5])<<16 | uint64(b[4])<<24 |
-		uint64(b[3])<<32 | uint64(b[2])<<40 | uint64(b[1])<<48 | uint64(b[0])<<56
-	return b[8:], x
-}
-
-func consumeUint32(b []byte) ([]byte, uint32) {
-	_ = b[3]
-	x := uint32(b[3]) | uint32(b[2])<<8 | uint32(b[1])<<16 | uint32(b[0])<<24
-	return b[4:], x
-}
-
-func (d *digest) Reset() {
-	if !d.is224 {
-		d.h[0] = init0
-		d.h[1] = init1
-		d.h[2] = init2
-		d.h[3] = init3
-		d.h[4] = init4
-		d.h[5] = init5
-		d.h[6] = init6
-		d.h[7] = init7
-	} else {
-		d.h[0] = init0_224
-		d.h[1] = init1_224
-		d.h[2] = init2_224
-		d.h[3] = init3_224
-		d.h[4] = init4_224
-		d.h[5] = init5_224
-		d.h[6] = init6_224
-		d.h[7] = init7_224
-	}
-	d.nx = 0
-	d.len = 0
-}
-
-// New returns a new hash.Hash computing the SHA256 checksum. The Hash
-// also implements encoding.BinaryMarshaler and
-// encoding.BinaryUnmarshaler to marshal and unmarshal the internal
-// state of the hash.
-func New() hash.Hash {
-	d := new(digest)
-	d.Reset()
-	return d
-}
-
-// New224 returns a new hash.Hash computing the SHA224 checksum.
-func New224() hash.Hash {
-	d := new(digest)
-	d.is224 = true
-	d.Reset()
-	return d
-}
-
-func (d *digest) Size() int {
-	if !d.is224 {
-		return Size
-	}
-	return Size224
-}
-
-func (d *digest) BlockSize() int { return BlockSize }
-
-func (d *digest) Write(p []byte) (nn int, err error) {
-	nn = len(p)
-	d.len += uint64(nn)
-	if d.nx > 0 {
-		n := copy(d.x[d.nx:], p)
-		d.nx += n
-		if d.nx == chunk {
-			block(d, d.x[:])
-			d.nx = 0
-		}
-		p = p[n:]
-	}
-	if len(p) >= chunk {
-		n := len(p) &^ (chunk - 1)
-		block(d, p[:n])
-		p = p[n:]
-	}
-	if len(p) > 0 {
-		d.nx = copy(d.x[:], p)
-	}
-	return
-}
-
-func (d *digest) Sum(in []byte) []byte {
-	// Make a copy of d so that caller can keep writing and summing.
-	d0 := *d
-	hash := d0.checkSum()
-	if d0.is224 {
-		return append(in, hash[:Size224]...)
-	}
-	return append(in, hash[:]...)
-}
-
-func (d *digest) checkSum() [Size]byte {
-	len := d.len
-	// Padding. Add a 1 bit and 0 bits until 56 bytes mod 64.
-	var tmp [64]byte
-	tmp[0] = 0x80
-	if len%64 < 56 {
-		d.Write(tmp[0 : 56-len%64])
-	} else {
-		d.Write(tmp[0 : 64+56-len%64])
-	}
-
-	// Length in bits.
-	len <<= 3
-	binary.BigEndian.PutUint64(tmp[:], len)
-	d.Write(tmp[0:8])
-
-	if d.nx != 0 {
-		panic("d.nx != 0")
-	}
-
-	var digest [Size]byte
-
-	binary.BigEndian.PutUint32(digest[0:], d.h[0])
-	binary.BigEndian.PutUint32(digest[4:], d.h[1])
-	binary.BigEndian.PutUint32(digest[8:], d.h[2])
-	binary.BigEndian.PutUint32(digest[12:], d.h[3])
-	binary.BigEndian.PutUint32(digest[16:], d.h[4])
-	binary.BigEndian.PutUint32(digest[20:], d.h[5])
-	binary.BigEndian.PutUint32(digest[24:], d.h[6])
-	if !d.is224 {
-		binary.BigEndian.PutUint32(digest[28:], d.h[7])
-	}
-
-	return digest
-}
-
-// Sum256 returns the SHA256 checksum of the data.
-func Sum256(data []byte) [Size]byte {
-	var d digest
-	d.Reset()
-	d.Write(data)
-	return d.checkSum()
-}
-
-// Sum224 returns the SHA224 checksum of the data.
-func Sum224(data []byte) [Size224]byte {
-	var d digest
-	d.is224 = true
-	d.Reset()
-	d.Write(data)
-	sum := d.checkSum()
-	ap := (*[Size224]byte)(sum[:])
-	return *ap
-}
diff --git a/contrib/go/_std_1.18/src/crypto/sha256/sha256block_decl.go b/contrib/go/_std_1.18/src/crypto/sha256/sha256block_decl.go
deleted file mode 100644
index c9c1194487..0000000000
--- a/contrib/go/_std_1.18/src/crypto/sha256/sha256block_decl.go
+++ /dev/null
@@ -1,11 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build 386 || amd64 || s390x || ppc64le
-
-package sha256
-
-//go:noescape
-
-func block(dig *digest, p []byte)
diff --git a/contrib/go/_std_1.18/src/crypto/sha512/sha512.go b/contrib/go/_std_1.18/src/crypto/sha512/sha512.go
deleted file mode 100644
index d5715558c0..0000000000
--- a/contrib/go/_std_1.18/src/crypto/sha512/sha512.go
+++ /dev/null
@@ -1,367 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package sha512 implements the SHA-384, SHA-512, SHA-512/224, and SHA-512/256
-// hash algorithms as defined in FIPS 180-4.
-//
-// All the hash.Hash implementations returned by this package also
-// implement encoding.BinaryMarshaler and encoding.BinaryUnmarshaler to
-// marshal and unmarshal the internal state of the hash.
-package sha512
-
-import (
-	"crypto"
-	"encoding/binary"
-	"errors"
-	"hash"
-)
-
-func init() {
-	crypto.RegisterHash(crypto.SHA384, New384)
-	crypto.RegisterHash(crypto.SHA512, New)
-	crypto.RegisterHash(crypto.SHA512_224, New512_224)
-	crypto.RegisterHash(crypto.SHA512_256, New512_256)
-}
-
-const (
-	// Size is the size, in bytes, of a SHA-512 checksum.
-	Size = 64
-
-	// Size224 is the size, in bytes, of a SHA-512/224 checksum.
-	Size224 = 28
-
-	// Size256 is the size, in bytes, of a SHA-512/256 checksum.
-	Size256 = 32
-
-	// Size384 is the size, in bytes, of a SHA-384 checksum.
-	Size384 = 48
-
-	// BlockSize is the block size, in bytes, of the SHA-512/224,
-	// SHA-512/256, SHA-384 and SHA-512 hash functions.
-	BlockSize = 128
-)
-
-const (
-	chunk     = 128
-	init0     = 0x6a09e667f3bcc908
-	init1     = 0xbb67ae8584caa73b
-	init2     = 0x3c6ef372fe94f82b
-	init3     = 0xa54ff53a5f1d36f1
-	init4     = 0x510e527fade682d1
-	init5     = 0x9b05688c2b3e6c1f
-	init6     = 0x1f83d9abfb41bd6b
-	init7     = 0x5be0cd19137e2179
-	init0_224 = 0x8c3d37c819544da2
-	init1_224 = 0x73e1996689dcd4d6
-	init2_224 = 0x1dfab7ae32ff9c82
-	init3_224 = 0x679dd514582f9fcf
-	init4_224 = 0x0f6d2b697bd44da8
-	init5_224 = 0x77e36f7304c48942
-	init6_224 = 0x3f9d85a86a1d36c8
-	init7_224 = 0x1112e6ad91d692a1
-	init0_256 = 0x22312194fc2bf72c
-	init1_256 = 0x9f555fa3c84c64c2
-	init2_256 = 0x2393b86b6f53b151
-	init3_256 = 0x963877195940eabd
-	init4_256 = 0x96283ee2a88effe3
-	init5_256 = 0xbe5e1e2553863992
-	init6_256 = 0x2b0199fc2c85b8aa
-	init7_256 = 0x0eb72ddc81c52ca2
-	init0_384 = 0xcbbb9d5dc1059ed8
-	init1_384 = 0x629a292a367cd507
-	init2_384 = 0x9159015a3070dd17
-	init3_384 = 0x152fecd8f70e5939
-	init4_384 = 0x67332667ffc00b31
-	init5_384 = 0x8eb44a8768581511
-	init6_384 = 0xdb0c2e0d64f98fa7
-	init7_384 = 0x47b5481dbefa4fa4
-)
-
-// digest represents the partial evaluation of a checksum.
-type digest struct {
-	h        [8]uint64
-	x        [chunk]byte
-	nx       int
-	len      uint64
-	function crypto.Hash
-}
-
-func (d *digest) Reset() {
-	switch d.function {
-	case crypto.SHA384:
-		d.h[0] = init0_384
-		d.h[1] = init1_384
-		d.h[2] = init2_384
-		d.h[3] = init3_384
-		d.h[4] = init4_384
-		d.h[5] = init5_384
-		d.h[6] = init6_384
-		d.h[7] = init7_384
-	case crypto.SHA512_224:
-		d.h[0] = init0_224
-		d.h[1] = init1_224
-		d.h[2] = init2_224
-		d.h[3] = init3_224
-		d.h[4] = init4_224
-		d.h[5] = init5_224
-		d.h[6] = init6_224
-		d.h[7] = init7_224
-	case crypto.SHA512_256:
-		d.h[0] = init0_256
-		d.h[1] = init1_256
-		d.h[2] = init2_256
-		d.h[3] = init3_256
-		d.h[4] = init4_256
-		d.h[5] = init5_256
-		d.h[6] = init6_256
-		d.h[7] = init7_256
-	default:
-		d.h[0] = init0
-		d.h[1] = init1
-		d.h[2] = init2
-		d.h[3] = init3
-		d.h[4] = init4
-		d.h[5] = init5
-		d.h[6] = init6
-		d.h[7] = init7
-	}
-	d.nx = 0
-	d.len = 0
-}
-
-const (
-	magic384      = "sha\x04"
-	magic512_224  = "sha\x05"
-	magic512_256  = "sha\x06"
-	magic512      = "sha\x07"
-	marshaledSize = len(magic512) + 8*8 + chunk + 8
-)
-
-func (d *digest) MarshalBinary() ([]byte, error) {
-	b := make([]byte, 0, marshaledSize)
-	switch d.function {
-	case crypto.SHA384:
-		b = append(b, magic384...)
-	case crypto.SHA512_224:
-		b = append(b, magic512_224...)
-	case crypto.SHA512_256:
-		b = append(b, magic512_256...)
-	case crypto.SHA512:
-		b = append(b, magic512...)
-	default:
-		return nil, errors.New("crypto/sha512: invalid hash function")
-	}
-	b = appendUint64(b, d.h[0])
-	b = appendUint64(b, d.h[1])
-	b = appendUint64(b, d.h[2])
-	b = appendUint64(b, d.h[3])
-	b = appendUint64(b, d.h[4])
-	b = appendUint64(b, d.h[5])
-	b = appendUint64(b, d.h[6])
-	b = appendUint64(b, d.h[7])
-	b = append(b, d.x[:d.nx]...)
-	b = b[:len(b)+len(d.x)-int(d.nx)] // already zero
-	b = appendUint64(b, d.len)
-	return b, nil
-}
-
-func (d *digest) UnmarshalBinary(b []byte) error {
-	if len(b) < len(magic512) {
-		return errors.New("crypto/sha512: invalid hash state identifier")
-	}
-	switch {
-	case d.function == crypto.SHA384 && string(b[:len(magic384)]) == magic384:
-	case d.function == crypto.SHA512_224 && string(b[:len(magic512_224)]) == magic512_224:
-	case d.function == crypto.SHA512_256 && string(b[:len(magic512_256)]) == magic512_256:
-	case d.function == crypto.SHA512 && string(b[:len(magic512)]) == magic512:
-	default:
-		return errors.New("crypto/sha512: invalid hash state identifier")
-	}
-	if len(b) != marshaledSize {
-		return errors.New("crypto/sha512: invalid hash state size")
-	}
-	b = b[len(magic512):]
-	b, d.h[0] = consumeUint64(b)
-	b, d.h[1] = consumeUint64(b)
-	b, d.h[2] = consumeUint64(b)
-	b, d.h[3] = consumeUint64(b)
-	b, d.h[4] = consumeUint64(b)
-	b, d.h[5] = consumeUint64(b)
-	b, d.h[6] = consumeUint64(b)
-	b, d.h[7] = consumeUint64(b)
-	b = b[copy(d.x[:], b):]
-	b, d.len = consumeUint64(b)
-	d.nx = int(d.len % chunk)
-	return nil
-}
-
-func appendUint64(b []byte, x uint64) []byte {
-	var a [8]byte
-	binary.BigEndian.PutUint64(a[:], x)
-	return append(b, a[:]...)
-}
-
-func consumeUint64(b []byte) ([]byte, uint64) {
-	_ = b[7]
-	x := uint64(b[7]) | uint64(b[6])<<8 | uint64(b[5])<<16 | uint64(b[4])<<24 |
-		uint64(b[3])<<32 | uint64(b[2])<<40 | uint64(b[1])<<48 | uint64(b[0])<<56
-	return b[8:], x
-}
-
-// New returns a new hash.Hash computing the SHA-512 checksum.
-func New() hash.Hash {
-	d := &digest{function: crypto.SHA512}
-	d.Reset()
-	return d
-}
-
-// New512_224 returns a new hash.Hash computing the SHA-512/224 checksum.
-func New512_224() hash.Hash {
-	d := &digest{function: crypto.SHA512_224}
-	d.Reset()
-	return d
-}
-
-// New512_256 returns a new hash.Hash computing the SHA-512/256 checksum.
-func New512_256() hash.Hash {
-	d := &digest{function: crypto.SHA512_256}
-	d.Reset()
-	return d
-}
-
-// New384 returns a new hash.Hash computing the SHA-384 checksum.
-func New384() hash.Hash {
-	d := &digest{function: crypto.SHA384}
-	d.Reset()
-	return d
-}
-
-func (d *digest) Size() int {
-	switch d.function {
-	case crypto.SHA512_224:
-		return Size224
-	case crypto.SHA512_256:
-		return Size256
-	case crypto.SHA384:
-		return Size384
-	default:
-		return Size
-	}
-}
-
-func (d *digest) BlockSize() int { return BlockSize }
-
-func (d *digest) Write(p []byte) (nn int, err error) {
-	nn = len(p)
-	d.len += uint64(nn)
-	if d.nx > 0 {
-		n := copy(d.x[d.nx:], p)
-		d.nx += n
-		if d.nx == chunk {
-			block(d, d.x[:])
-			d.nx = 0
-		}
-		p = p[n:]
-	}
-	if len(p) >= chunk {
-		n := len(p) &^ (chunk - 1)
-		block(d, p[:n])
-		p = p[n:]
-	}
-	if len(p) > 0 {
-		d.nx = copy(d.x[:], p)
-	}
-	return
-}
-
-func (d *digest) Sum(in []byte) []byte {
-	// Make a copy of d so that caller can keep writing and summing.
-	d0 := new(digest)
-	*d0 = *d
-	hash := d0.checkSum()
-	switch d0.function {
-	case crypto.SHA384:
-		return append(in, hash[:Size384]...)
-	case crypto.SHA512_224:
-		return append(in, hash[:Size224]...)
-	case crypto.SHA512_256:
-		return append(in, hash[:Size256]...)
-	default:
-		return append(in, hash[:]...)
-	}
-}
-
-func (d *digest) checkSum() [Size]byte {
-	// Padding. Add a 1 bit and 0 bits until 112 bytes mod 128.
-	len := d.len
-	var tmp [128]byte
-	tmp[0] = 0x80
-	if len%128 < 112 {
-		d.Write(tmp[0 : 112-len%128])
-	} else {
-		d.Write(tmp[0 : 128+112-len%128])
-	}
-
-	// Length in bits.
-	len <<= 3
-	binary.BigEndian.PutUint64(tmp[0:], 0) // upper 64 bits are always zero, because len variable has type uint64
-	binary.BigEndian.PutUint64(tmp[8:], len)
-	d.Write(tmp[0:16])
-
-	if d.nx != 0 {
-		panic("d.nx != 0")
-	}
-
-	var digest [Size]byte
-	binary.BigEndian.PutUint64(digest[0:], d.h[0])
-	binary.BigEndian.PutUint64(digest[8:], d.h[1])
-	binary.BigEndian.PutUint64(digest[16:], d.h[2])
-	binary.BigEndian.PutUint64(digest[24:], d.h[3])
-	binary.BigEndian.PutUint64(digest[32:], d.h[4])
-	binary.BigEndian.PutUint64(digest[40:], d.h[5])
-	if d.function != crypto.SHA384 {
-		binary.BigEndian.PutUint64(digest[48:], d.h[6])
-		binary.BigEndian.PutUint64(digest[56:], d.h[7])
-	}
-
-	return digest
-}
-
-// Sum512 returns the SHA512 checksum of the data.
-func Sum512(data []byte) [Size]byte {
-	d := digest{function: crypto.SHA512}
-	d.Reset()
-	d.Write(data)
-	return d.checkSum()
-}
-
-// Sum384 returns the SHA384 checksum of the data.
-func Sum384(data []byte) [Size384]byte {
-	d := digest{function: crypto.SHA384}
-	d.Reset()
-	d.Write(data)
-	sum := d.checkSum()
-	ap := (*[Size384]byte)(sum[:])
-	return *ap
-}
-
-// Sum512_224 returns the Sum512/224 checksum of the data.
-func Sum512_224(data []byte) [Size224]byte {
-	d := digest{function: crypto.SHA512_224}
-	d.Reset()
-	d.Write(data)
-	sum := d.checkSum()
-	ap := (*[Size224]byte)(sum[:])
-	return *ap
-}
-
-// Sum512_256 returns the Sum512/256 checksum of the data.
-func Sum512_256(data []byte) [Size256]byte {
-	d := digest{function: crypto.SHA512_256}
-	d.Reset()
-	d.Write(data)
-	sum := d.checkSum()
-	ap := (*[Size256]byte)(sum[:])
-	return *ap
-}
diff --git a/contrib/go/_std_1.18/src/crypto/subtle/constant_time.go b/contrib/go/_std_1.18/src/crypto/subtle/constant_time.go
deleted file mode 100644
index 7c3cf05c46..0000000000
--- a/contrib/go/_std_1.18/src/crypto/subtle/constant_time.go
+++ /dev/null
@@ -1,61 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package subtle implements functions that are often useful in cryptographic
-// code but require careful thought to use correctly.
-package subtle
-
-// ConstantTimeCompare returns 1 if the two slices, x and y, have equal contents
-// and 0 otherwise. The time taken is a function of the length of the slices and
-// is independent of the contents.
-func ConstantTimeCompare(x, y []byte) int {
-	if len(x) != len(y) {
-		return 0
-	}
-
-	var v byte
-
-	for i := 0; i < len(x); i++ {
-		v |= x[i] ^ y[i]
-	}
-
-	return ConstantTimeByteEq(v, 0)
-}
-
-// ConstantTimeSelect returns x if v == 1 and y if v == 0.
-// Its behavior is undefined if v takes any other value.
-func ConstantTimeSelect(v, x, y int) int { return ^(v-1)&x | (v-1)&y }
-
-// ConstantTimeByteEq returns 1 if x == y and 0 otherwise.
-func ConstantTimeByteEq(x, y uint8) int {
-	return int((uint32(x^y) - 1) >> 31)
-}
-
-// ConstantTimeEq returns 1 if x == y and 0 otherwise.
-func ConstantTimeEq(x, y int32) int {
-	return int((uint64(uint32(x^y)) - 1) >> 63)
-}
-
-// ConstantTimeCopy copies the contents of y into x (a slice of equal length)
-// if v == 1. If v == 0, x is left unchanged. Its behavior is undefined if v
-// takes any other value.
-func ConstantTimeCopy(v int, x, y []byte) {
-	if len(x) != len(y) {
-		panic("subtle: slices have different lengths")
-	}
-
-	xmask := byte(v - 1)
-	ymask := byte(^(v - 1))
-	for i := 0; i < len(x); i++ {
-		x[i] = x[i]&xmask | y[i]&ymask
-	}
-}
-
-// ConstantTimeLessOrEq returns 1 if x <= y and 0 otherwise.
-// Its behavior is undefined if x or y are negative or > 2**31 - 1.
-func ConstantTimeLessOrEq(x, y int) int {
-	x32 := int32(x)
-	y32 := int32(y)
-	return int(((x32 - y32 - 1) >> 31) & 1)
-}
diff --git a/contrib/go/_std_1.18/src/crypto/tls/auth.go b/contrib/go/_std_1.18/src/crypto/tls/auth.go
deleted file mode 100644
index a9df0da6d6..0000000000
--- a/contrib/go/_std_1.18/src/crypto/tls/auth.go
+++ /dev/null
@@ -1,289 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package tls
-
-import (
-	"bytes"
-	"crypto"
-	"crypto/ecdsa"
-	"crypto/ed25519"
-	"crypto/elliptic"
-	"crypto/rsa"
-	"errors"
-	"fmt"
-	"hash"
-	"io"
-)
-
-// verifyHandshakeSignature verifies a signature against pre-hashed
-// (if required) handshake contents.
-func verifyHandshakeSignature(sigType uint8, pubkey crypto.PublicKey, hashFunc crypto.Hash, signed, sig []byte) error {
-	switch sigType {
-	case signatureECDSA:
-		pubKey, ok := pubkey.(*ecdsa.PublicKey)
-		if !ok {
-			return fmt.Errorf("expected an ECDSA public key, got %T", pubkey)
-		}
-		if !ecdsa.VerifyASN1(pubKey, signed, sig) {
-			return errors.New("ECDSA verification failure")
-		}
-	case signatureEd25519:
-		pubKey, ok := pubkey.(ed25519.PublicKey)
-		if !ok {
-			return fmt.Errorf("expected an Ed25519 public key, got %T", pubkey)
-		}
-		if !ed25519.Verify(pubKey, signed, sig) {
-			return errors.New("Ed25519 verification failure")
-		}
-	case signaturePKCS1v15:
-		pubKey, ok := pubkey.(*rsa.PublicKey)
-		if !ok {
-			return fmt.Errorf("expected an RSA public key, got %T", pubkey)
-		}
-		if err := rsa.VerifyPKCS1v15(pubKey, hashFunc, signed, sig); err != nil {
-			return err
-		}
-	case signatureRSAPSS:
-		pubKey, ok := pubkey.(*rsa.PublicKey)
-		if !ok {
-			return fmt.Errorf("expected an RSA public key, got %T", pubkey)
-		}
-		signOpts := &rsa.PSSOptions{SaltLength: rsa.PSSSaltLengthEqualsHash}
-		if err := rsa.VerifyPSS(pubKey, hashFunc, signed, sig, signOpts); err != nil {
-			return err
-		}
-	default:
-		return errors.New("internal error: unknown signature type")
-	}
-	return nil
-}
-
-const (
-	serverSignatureContext = "TLS 1.3, server CertificateVerify\x00"
-	clientSignatureContext = "TLS 1.3, client CertificateVerify\x00"
-)
-
-var signaturePadding = []byte{
-	0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
-	0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
-	0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
-	0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
-	0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
-	0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
-	0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
-	0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
-}
-
-// signedMessage returns the pre-hashed (if necessary) message to be signed by
-// certificate keys in TLS 1.3. See RFC 8446, Section 4.4.3.
-func signedMessage(sigHash crypto.Hash, context string, transcript hash.Hash) []byte {
-	if sigHash == directSigning {
-		b := &bytes.Buffer{}
-		b.Write(signaturePadding)
-		io.WriteString(b, context)
-		b.Write(transcript.Sum(nil))
-		return b.Bytes()
-	}
-	h := sigHash.New()
-	h.Write(signaturePadding)
-	io.WriteString(h, context)
-	h.Write(transcript.Sum(nil))
-	return h.Sum(nil)
-}
-
-// typeAndHashFromSignatureScheme returns the corresponding signature type and
-// crypto.Hash for a given TLS SignatureScheme.
-func typeAndHashFromSignatureScheme(signatureAlgorithm SignatureScheme) (sigType uint8, hash crypto.Hash, err error) {
-	switch signatureAlgorithm {
-	case PKCS1WithSHA1, PKCS1WithSHA256, PKCS1WithSHA384, PKCS1WithSHA512:
-		sigType = signaturePKCS1v15
-	case PSSWithSHA256, PSSWithSHA384, PSSWithSHA512:
-		sigType = signatureRSAPSS
-	case ECDSAWithSHA1, ECDSAWithP256AndSHA256, ECDSAWithP384AndSHA384, ECDSAWithP521AndSHA512:
-		sigType = signatureECDSA
-	case Ed25519:
-		sigType = signatureEd25519
-	default:
-		return 0, 0, fmt.Errorf("unsupported signature algorithm: %v", signatureAlgorithm)
-	}
-	switch signatureAlgorithm {
-	case PKCS1WithSHA1, ECDSAWithSHA1:
-		hash = crypto.SHA1
-	case PKCS1WithSHA256, PSSWithSHA256, ECDSAWithP256AndSHA256:
-		hash = crypto.SHA256
-	case PKCS1WithSHA384, PSSWithSHA384, ECDSAWithP384AndSHA384:
-		hash = crypto.SHA384
-	case PKCS1WithSHA512, PSSWithSHA512, ECDSAWithP521AndSHA512:
-		hash = crypto.SHA512
-	case Ed25519:
-		hash = directSigning
-	default:
-		return 0, 0, fmt.Errorf("unsupported signature algorithm: %v", signatureAlgorithm)
-	}
-	return sigType, hash, nil
-}
-
-// legacyTypeAndHashFromPublicKey returns the fixed signature type and crypto.Hash for
-// a given public key used with TLS 1.0 and 1.1, before the introduction of
-// signature algorithm negotiation.
-func legacyTypeAndHashFromPublicKey(pub crypto.PublicKey) (sigType uint8, hash crypto.Hash, err error) {
-	switch pub.(type) {
-	case *rsa.PublicKey:
-		return signaturePKCS1v15, crypto.MD5SHA1, nil
-	case *ecdsa.PublicKey:
-		return signatureECDSA, crypto.SHA1, nil
-	case ed25519.PublicKey:
-		// RFC 8422 specifies support for Ed25519 in TLS 1.0 and 1.1,
-		// but it requires holding on to a handshake transcript to do a
-		// full signature, and not even OpenSSL bothers with the
-		// complexity, so we can't even test it properly.
-		return 0, 0, fmt.Errorf("tls: Ed25519 public keys are not supported before TLS 1.2")
-	default:
-		return 0, 0, fmt.Errorf("tls: unsupported public key: %T", pub)
-	}
-}
-
-var rsaSignatureSchemes = []struct {
-	scheme          SignatureScheme
-	minModulusBytes int
-	maxVersion      uint16
-}{
-	// RSA-PSS is used with PSSSaltLengthEqualsHash, and requires
-	//    emLen >= hLen + sLen + 2
-	{PSSWithSHA256, crypto.SHA256.Size()*2 + 2, VersionTLS13},
-	{PSSWithSHA384, crypto.SHA384.Size()*2 + 2, VersionTLS13},
-	{PSSWithSHA512, crypto.SHA512.Size()*2 + 2, VersionTLS13},
-	// PKCS #1 v1.5 uses prefixes from hashPrefixes in crypto/rsa, and requires
-	//    emLen >= len(prefix) + hLen + 11
-	// TLS 1.3 dropped support for PKCS #1 v1.5 in favor of RSA-PSS.
-	{PKCS1WithSHA256, 19 + crypto.SHA256.Size() + 11, VersionTLS12},
-	{PKCS1WithSHA384, 19 + crypto.SHA384.Size() + 11, VersionTLS12},
-	{PKCS1WithSHA512, 19 + crypto.SHA512.Size() + 11, VersionTLS12},
-	{PKCS1WithSHA1, 15 + crypto.SHA1.Size() + 11, VersionTLS12},
-}
-
-// signatureSchemesForCertificate returns the list of supported SignatureSchemes
-// for a given certificate, based on the public key and the protocol version,
-// and optionally filtered by its explicit SupportedSignatureAlgorithms.
-//
-// This function must be kept in sync with supportedSignatureAlgorithms.
-func signatureSchemesForCertificate(version uint16, cert *Certificate) []SignatureScheme {
-	priv, ok := cert.PrivateKey.(crypto.Signer)
-	if !ok {
-		return nil
-	}
-
-	var sigAlgs []SignatureScheme
-	switch pub := priv.Public().(type) {
-	case *ecdsa.PublicKey:
-		if version != VersionTLS13 {
-			// In TLS 1.2 and earlier, ECDSA algorithms are not
-			// constrained to a single curve.
-			sigAlgs = []SignatureScheme{
-				ECDSAWithP256AndSHA256,
-				ECDSAWithP384AndSHA384,
-				ECDSAWithP521AndSHA512,
-				ECDSAWithSHA1,
-			}
-			break
-		}
-		switch pub.Curve {
-		case elliptic.P256():
-			sigAlgs = []SignatureScheme{ECDSAWithP256AndSHA256}
-		case elliptic.P384():
-			sigAlgs = []SignatureScheme{ECDSAWithP384AndSHA384}
-		case elliptic.P521():
-			sigAlgs = []SignatureScheme{ECDSAWithP521AndSHA512}
-		default:
-			return nil
-		}
-	case *rsa.PublicKey:
-		size := pub.Size()
-		sigAlgs = make([]SignatureScheme, 0, len(rsaSignatureSchemes))
-		for _, candidate := range rsaSignatureSchemes {
-			if size >= candidate.minModulusBytes && version <= candidate.maxVersion {
-				sigAlgs = append(sigAlgs, candidate.scheme)
-			}
-		}
-	case ed25519.PublicKey:
-		sigAlgs = []SignatureScheme{Ed25519}
-	default:
-		return nil
-	}
-
-	if cert.SupportedSignatureAlgorithms != nil {
-		var filteredSigAlgs []SignatureScheme
-		for _, sigAlg := range sigAlgs {
-			if isSupportedSignatureAlgorithm(sigAlg, cert.SupportedSignatureAlgorithms) {
-				filteredSigAlgs = append(filteredSigAlgs, sigAlg)
-			}
-		}
-		return filteredSigAlgs
-	}
-	return sigAlgs
-}
-
-// selectSignatureScheme picks a SignatureScheme from the peer's preference list
-// that works with the selected certificate. It's only called for protocol
-// versions that support signature algorithms, so TLS 1.2 and 1.3.
-func selectSignatureScheme(vers uint16, c *Certificate, peerAlgs []SignatureScheme) (SignatureScheme, error) {
-	supportedAlgs := signatureSchemesForCertificate(vers, c)
-	if len(supportedAlgs) == 0 {
-		return 0, unsupportedCertificateError(c)
-	}
-	if len(peerAlgs) == 0 && vers == VersionTLS12 {
-		// For TLS 1.2, if the client didn't send signature_algorithms then we
-		// can assume that it supports SHA1. See RFC 5246, Section 7.4.1.4.1.
-		peerAlgs = []SignatureScheme{PKCS1WithSHA1, ECDSAWithSHA1}
-	}
-	// Pick signature scheme in the peer's preference order, as our
-	// preference order is not configurable.
-	for _, preferredAlg := range peerAlgs {
-		if isSupportedSignatureAlgorithm(preferredAlg, supportedAlgs) {
-			return preferredAlg, nil
-		}
-	}
-	return 0, errors.New("tls: peer doesn't support any of the certificate's signature algorithms")
-}
-
-// unsupportedCertificateError returns a helpful error for certificates with
-// an unsupported private key.
-func unsupportedCertificateError(cert *Certificate) error {
-	switch cert.PrivateKey.(type) {
-	case rsa.PrivateKey, ecdsa.PrivateKey:
-		return fmt.Errorf("tls: unsupported certificate: private key is %T, expected *%T",
-			cert.PrivateKey, cert.PrivateKey)
-	case *ed25519.PrivateKey:
-		return fmt.Errorf("tls: unsupported certificate: private key is *ed25519.PrivateKey, expected ed25519.PrivateKey")
-	}
-
-	signer, ok := cert.PrivateKey.(crypto.Signer)
-	if !ok {
-		return fmt.Errorf("tls: certificate private key (%T) does not implement crypto.Signer",
-			cert.PrivateKey)
-	}
-
-	switch pub := signer.Public().(type) {
-	case *ecdsa.PublicKey:
-		switch pub.Curve {
-		case elliptic.P256():
-		case elliptic.P384():
-		case elliptic.P521():
-		default:
-			return fmt.Errorf("tls: unsupported certificate curve (%s)", pub.Curve.Params().Name)
-		}
-	case *rsa.PublicKey:
-		return fmt.Errorf("tls: certificate RSA key size too small for supported signature algorithms")
-	case ed25519.PublicKey:
-	default:
-		return fmt.Errorf("tls: unsupported certificate key (%T)", pub)
-	}
-
-	if cert.SupportedSignatureAlgorithms != nil {
-		return fmt.Errorf("tls: peer doesn't support the certificate custom signature algorithms")
-	}
-
-	return fmt.Errorf("tls: internal error: unsupported key (%T)", cert.PrivateKey)
-}
diff --git a/contrib/go/_std_1.18/src/crypto/tls/cipher_suites.go b/contrib/go/_std_1.18/src/crypto/tls/cipher_suites.go
deleted file mode 100644
index d164991eec..0000000000
--- a/contrib/go/_std_1.18/src/crypto/tls/cipher_suites.go
+++ /dev/null
@@ -1,689 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package tls
-
-import (
-	"crypto"
-	"crypto/aes"
-	"crypto/cipher"
-	"crypto/des"
-	"crypto/hmac"
-	"crypto/rc4"
-	"crypto/sha1"
-	"crypto/sha256"
-	"fmt"
-	"hash"
-	"internal/cpu"
-	"runtime"
-
-	"golang.org/x/crypto/chacha20poly1305"
-)
-
-// CipherSuite is a TLS cipher suite. Note that most functions in this package
-// accept and expose cipher suite IDs instead of this type.
-type CipherSuite struct {
-	ID   uint16
-	Name string
-
-	// Supported versions is the list of TLS protocol versions that can
-	// negotiate this cipher suite.
-	SupportedVersions []uint16
-
-	// Insecure is true if the cipher suite has known security issues
-	// due to its primitives, design, or implementation.
-	Insecure bool
-}
-
-var (
-	supportedUpToTLS12 = []uint16{VersionTLS10, VersionTLS11, VersionTLS12}
-	supportedOnlyTLS12 = []uint16{VersionTLS12}
-	supportedOnlyTLS13 = []uint16{VersionTLS13}
-)
-
-// CipherSuites returns a list of cipher suites currently implemented by this
-// package, excluding those with security issues, which are returned by
-// InsecureCipherSuites.
-//
-// The list is sorted by ID. Note that the default cipher suites selected by
-// this package might depend on logic that can't be captured by a static list,
-// and might not match those returned by this function.
-func CipherSuites() []*CipherSuite {
-	return []*CipherSuite{
-		{TLS_RSA_WITH_AES_128_CBC_SHA, "TLS_RSA_WITH_AES_128_CBC_SHA", supportedUpToTLS12, false},
-		{TLS_RSA_WITH_AES_256_CBC_SHA, "TLS_RSA_WITH_AES_256_CBC_SHA", supportedUpToTLS12, false},
-		{TLS_RSA_WITH_AES_128_GCM_SHA256, "TLS_RSA_WITH_AES_128_GCM_SHA256", supportedOnlyTLS12, false},
-		{TLS_RSA_WITH_AES_256_GCM_SHA384, "TLS_RSA_WITH_AES_256_GCM_SHA384", supportedOnlyTLS12, false},
-
-		{TLS_AES_128_GCM_SHA256, "TLS_AES_128_GCM_SHA256", supportedOnlyTLS13, false},
-		{TLS_AES_256_GCM_SHA384, "TLS_AES_256_GCM_SHA384", supportedOnlyTLS13, false},
-		{TLS_CHACHA20_POLY1305_SHA256, "TLS_CHACHA20_POLY1305_SHA256", supportedOnlyTLS13, false},
-
-		{TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA, "TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA", supportedUpToTLS12, false},
-		{TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA, "TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA", supportedUpToTLS12, false},
-		{TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA, "TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA", supportedUpToTLS12, false},
-		{TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA, "TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA", supportedUpToTLS12, false},
-		{TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256, "TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256", supportedOnlyTLS12, false},
-		{TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384, "TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384", supportedOnlyTLS12, false},
-		{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256, "TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256", supportedOnlyTLS12, false},
-		{TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384, "TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384", supportedOnlyTLS12, false},
-		{TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256, "TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256", supportedOnlyTLS12, false},
-		{TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256, "TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256", supportedOnlyTLS12, false},
-	}
-}
-
-// InsecureCipherSuites returns a list of cipher suites currently implemented by
-// this package and which have security issues.
-//
-// Most applications should not use the cipher suites in this list, and should
-// only use those returned by CipherSuites.
-func InsecureCipherSuites() []*CipherSuite {
-	// This list includes RC4, CBC_SHA256, and 3DES cipher suites. See
-	// cipherSuitesPreferenceOrder for details.
-	return []*CipherSuite{
-		{TLS_RSA_WITH_RC4_128_SHA, "TLS_RSA_WITH_RC4_128_SHA", supportedUpToTLS12, true},
-		{TLS_RSA_WITH_3DES_EDE_CBC_SHA, "TLS_RSA_WITH_3DES_EDE_CBC_SHA", supportedUpToTLS12, true},
-		{TLS_RSA_WITH_AES_128_CBC_SHA256, "TLS_RSA_WITH_AES_128_CBC_SHA256", supportedOnlyTLS12, true},
-		{TLS_ECDHE_ECDSA_WITH_RC4_128_SHA, "TLS_ECDHE_ECDSA_WITH_RC4_128_SHA", supportedUpToTLS12, true},
-		{TLS_ECDHE_RSA_WITH_RC4_128_SHA, "TLS_ECDHE_RSA_WITH_RC4_128_SHA", supportedUpToTLS12, true},
-		{TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA, "TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA", supportedUpToTLS12, true},
-		{TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256, "TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256", supportedOnlyTLS12, true},
-		{TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256, "TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256", supportedOnlyTLS12, true},
-	}
-}
-
-// CipherSuiteName returns the standard name for the passed cipher suite ID
-// (e.g. "TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256"), or a fallback representation
-// of the ID value if the cipher suite is not implemented by this package.
-func CipherSuiteName(id uint16) string {
-	for _, c := range CipherSuites() {
-		if c.ID == id {
-			return c.Name
-		}
-	}
-	for _, c := range InsecureCipherSuites() {
-		if c.ID == id {
-			return c.Name
-		}
-	}
-	return fmt.Sprintf("0x%04X", id)
-}
-
-const (
-	// suiteECDHE indicates that the cipher suite involves elliptic curve
-	// Diffie-Hellman. This means that it should only be selected when the
-	// client indicates that it supports ECC with a curve and point format
-	// that we're happy with.
-	suiteECDHE = 1 << iota
-	// suiteECSign indicates that the cipher suite involves an ECDSA or
-	// EdDSA signature and therefore may only be selected when the server's
-	// certificate is ECDSA or EdDSA. If this is not set then the cipher suite
-	// is RSA based.
-	suiteECSign
-	// suiteTLS12 indicates that the cipher suite should only be advertised
-	// and accepted when using TLS 1.2.
-	suiteTLS12
-	// suiteSHA384 indicates that the cipher suite uses SHA384 as the
-	// handshake hash.
-	suiteSHA384
-)
-
-// A cipherSuite is a TLS 1.0–1.2 cipher suite, and defines the key exchange
-// mechanism, as well as the cipher+MAC pair or the AEAD.
-type cipherSuite struct {
-	id uint16
-	// the lengths, in bytes, of the key material needed for each component.
-	keyLen int
-	macLen int
-	ivLen  int
-	ka     func(version uint16) keyAgreement
-	// flags is a bitmask of the suite* values, above.
-	flags  int
-	cipher func(key, iv []byte, isRead bool) any
-	mac    func(key []byte) hash.Hash
-	aead   func(key, fixedNonce []byte) aead
-}
-
-var cipherSuites = []*cipherSuite{ // TODO: replace with a map, since the order doesn't matter.
-	{TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305, 32, 0, 12, ecdheRSAKA, suiteECDHE | suiteTLS12, nil, nil, aeadChaCha20Poly1305},
-	{TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305, 32, 0, 12, ecdheECDSAKA, suiteECDHE | suiteECSign | suiteTLS12, nil, nil, aeadChaCha20Poly1305},
-	{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256, 16, 0, 4, ecdheRSAKA, suiteECDHE | suiteTLS12, nil, nil, aeadAESGCM},
-	{TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256, 16, 0, 4, ecdheECDSAKA, suiteECDHE | suiteECSign | suiteTLS12, nil, nil, aeadAESGCM},
-	{TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384, 32, 0, 4, ecdheRSAKA, suiteECDHE | suiteTLS12 | suiteSHA384, nil, nil, aeadAESGCM},
-	{TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384, 32, 0, 4, ecdheECDSAKA, suiteECDHE | suiteECSign | suiteTLS12 | suiteSHA384, nil, nil, aeadAESGCM},
-	{TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256, 16, 32, 16, ecdheRSAKA, suiteECDHE | suiteTLS12, cipherAES, macSHA256, nil},
-	{TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA, 16, 20, 16, ecdheRSAKA, suiteECDHE, cipherAES, macSHA1, nil},
-	{TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256, 16, 32, 16, ecdheECDSAKA, suiteECDHE | suiteECSign | suiteTLS12, cipherAES, macSHA256, nil},
-	{TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA, 16, 20, 16, ecdheECDSAKA, suiteECDHE | suiteECSign, cipherAES, macSHA1, nil},
-	{TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA, 32, 20, 16, ecdheRSAKA, suiteECDHE, cipherAES, macSHA1, nil},
-	{TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA, 32, 20, 16, ecdheECDSAKA, suiteECDHE | suiteECSign, cipherAES, macSHA1, nil},
-	{TLS_RSA_WITH_AES_128_GCM_SHA256, 16, 0, 4, rsaKA, suiteTLS12, nil, nil, aeadAESGCM},
-	{TLS_RSA_WITH_AES_256_GCM_SHA384, 32, 0, 4, rsaKA, suiteTLS12 | suiteSHA384, nil, nil, aeadAESGCM},
-	{TLS_RSA_WITH_AES_128_CBC_SHA256, 16, 32, 16, rsaKA, suiteTLS12, cipherAES, macSHA256, nil},
-	{TLS_RSA_WITH_AES_128_CBC_SHA, 16, 20, 16, rsaKA, 0, cipherAES, macSHA1, nil},
-	{TLS_RSA_WITH_AES_256_CBC_SHA, 32, 20, 16, rsaKA, 0, cipherAES, macSHA1, nil},
-	{TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA, 24, 20, 8, ecdheRSAKA, suiteECDHE, cipher3DES, macSHA1, nil},
-	{TLS_RSA_WITH_3DES_EDE_CBC_SHA, 24, 20, 8, rsaKA, 0, cipher3DES, macSHA1, nil},
-	{TLS_RSA_WITH_RC4_128_SHA, 16, 20, 0, rsaKA, 0, cipherRC4, macSHA1, nil},
-	{TLS_ECDHE_RSA_WITH_RC4_128_SHA, 16, 20, 0, ecdheRSAKA, suiteECDHE, cipherRC4, macSHA1, nil},
-	{TLS_ECDHE_ECDSA_WITH_RC4_128_SHA, 16, 20, 0, ecdheECDSAKA, suiteECDHE | suiteECSign, cipherRC4, macSHA1, nil},
-}
-
-// selectCipherSuite returns the first TLS 1.0–1.2 cipher suite from ids which
-// is also in supportedIDs and passes the ok filter.
-func selectCipherSuite(ids, supportedIDs []uint16, ok func(*cipherSuite) bool) *cipherSuite {
-	for _, id := range ids {
-		candidate := cipherSuiteByID(id)
-		if candidate == nil || !ok(candidate) {
-			continue
-		}
-
-		for _, suppID := range supportedIDs {
-			if id == suppID {
-				return candidate
-			}
-		}
-	}
-	return nil
-}
-
-// A cipherSuiteTLS13 defines only the pair of the AEAD algorithm and hash
-// algorithm to be used with HKDF. See RFC 8446, Appendix B.4.
-type cipherSuiteTLS13 struct {
-	id     uint16
-	keyLen int
-	aead   func(key, fixedNonce []byte) aead
-	hash   crypto.Hash
-}
-
-var cipherSuitesTLS13 = []*cipherSuiteTLS13{ // TODO: replace with a map.
-	{TLS_AES_128_GCM_SHA256, 16, aeadAESGCMTLS13, crypto.SHA256},
-	{TLS_CHACHA20_POLY1305_SHA256, 32, aeadChaCha20Poly1305, crypto.SHA256},
-	{TLS_AES_256_GCM_SHA384, 32, aeadAESGCMTLS13, crypto.SHA384},
-}
-
-// cipherSuitesPreferenceOrder is the order in which we'll select (on the
-// server) or advertise (on the client) TLS 1.0–1.2 cipher suites.
-//
-// Cipher suites are filtered but not reordered based on the application and
-// peer's preferences, meaning we'll never select a suite lower in this list if
-// any higher one is available. This makes it more defensible to keep weaker
-// cipher suites enabled, especially on the server side where we get the last
-// word, since there are no known downgrade attacks on cipher suites selection.
-//
-// The list is sorted by applying the following priority rules, stopping at the
-// first (most important) applicable one:
-//
-//   - Anything else comes before RC4
-//
-//       RC4 has practically exploitable biases. See https://www.rc4nomore.com.
-//
-//   - Anything else comes before CBC_SHA256
-//
-//       SHA-256 variants of the CBC ciphersuites don't implement any Lucky13
-//       countermeasures. See http://www.isg.rhul.ac.uk/tls/Lucky13.html and
-//       https://www.imperialviolet.org/2013/02/04/luckythirteen.html.
-//
-//   - Anything else comes before 3DES
-//
-//       3DES has 64-bit blocks, which makes it fundamentally susceptible to
-//       birthday attacks. See https://sweet32.info.
-//
-//   - ECDHE comes before anything else
-//
-//       Once we got the broken stuff out of the way, the most important
-//       property a cipher suite can have is forward secrecy. We don't
-//       implement FFDHE, so that means ECDHE.
-//
-//   - AEADs come before CBC ciphers
-//
-//       Even with Lucky13 countermeasures, MAC-then-Encrypt CBC cipher suites
-//       are fundamentally fragile, and suffered from an endless sequence of
-//       padding oracle attacks. See https://eprint.iacr.org/2015/1129,
-//       https://www.imperialviolet.org/2014/12/08/poodleagain.html, and
-//       https://blog.cloudflare.com/yet-another-padding-oracle-in-openssl-cbc-ciphersuites/.
-//
-//   - AES comes before ChaCha20
-//
-//       When AES hardware is available, AES-128-GCM and AES-256-GCM are faster
-//       than ChaCha20Poly1305.
-//
-//       When AES hardware is not available, AES-128-GCM is one or more of: much
-//       slower, way more complex, and less safe (because not constant time)
-//       than ChaCha20Poly1305.
-//
-//       We use this list if we think both peers have AES hardware, and
-//       cipherSuitesPreferenceOrderNoAES otherwise.
-//
-//   - AES-128 comes before AES-256
-//
-//       The only potential advantages of AES-256 are better multi-target
-//       margins, and hypothetical post-quantum properties. Neither apply to
-//       TLS, and AES-256 is slower due to its four extra rounds (which don't
-//       contribute to the advantages above).
-//
-//   - ECDSA comes before RSA
-//
-//       The relative order of ECDSA and RSA cipher suites doesn't matter,
-//       as they depend on the certificate. Pick one to get a stable order.
-//
-var cipherSuitesPreferenceOrder = []uint16{
-	// AEADs w/ ECDHE
-	TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256, TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
-	TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384, TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
-	TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305, TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305,
-
-	// CBC w/ ECDHE
-	TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA, TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
-	TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA, TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
-
-	// AEADs w/o ECDHE
-	TLS_RSA_WITH_AES_128_GCM_SHA256,
-	TLS_RSA_WITH_AES_256_GCM_SHA384,
-
-	// CBC w/o ECDHE
-	TLS_RSA_WITH_AES_128_CBC_SHA,
-	TLS_RSA_WITH_AES_256_CBC_SHA,
-
-	// 3DES
-	TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA,
-	TLS_RSA_WITH_3DES_EDE_CBC_SHA,
-
-	// CBC_SHA256
-	TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256, TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256,
-	TLS_RSA_WITH_AES_128_CBC_SHA256,
-
-	// RC4
-	TLS_ECDHE_ECDSA_WITH_RC4_128_SHA, TLS_ECDHE_RSA_WITH_RC4_128_SHA,
-	TLS_RSA_WITH_RC4_128_SHA,
-}
-
-var cipherSuitesPreferenceOrderNoAES = []uint16{
-	// ChaCha20Poly1305
-	TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305, TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305,
-
-	// AES-GCM w/ ECDHE
-	TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256, TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
-	TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384, TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
-
-	// The rest of cipherSuitesPreferenceOrder.
-	TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA, TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
-	TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA, TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
-	TLS_RSA_WITH_AES_128_GCM_SHA256,
-	TLS_RSA_WITH_AES_256_GCM_SHA384,
-	TLS_RSA_WITH_AES_128_CBC_SHA,
-	TLS_RSA_WITH_AES_256_CBC_SHA,
-	TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA,
-	TLS_RSA_WITH_3DES_EDE_CBC_SHA,
-	TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256, TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256,
-	TLS_RSA_WITH_AES_128_CBC_SHA256,
-	TLS_ECDHE_ECDSA_WITH_RC4_128_SHA, TLS_ECDHE_RSA_WITH_RC4_128_SHA,
-	TLS_RSA_WITH_RC4_128_SHA,
-}
-
-// disabledCipherSuites are not used unless explicitly listed in
-// Config.CipherSuites. They MUST be at the end of cipherSuitesPreferenceOrder.
-var disabledCipherSuites = []uint16{
-	// CBC_SHA256
-	TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256, TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256,
-	TLS_RSA_WITH_AES_128_CBC_SHA256,
-
-	// RC4
-	TLS_ECDHE_ECDSA_WITH_RC4_128_SHA, TLS_ECDHE_RSA_WITH_RC4_128_SHA,
-	TLS_RSA_WITH_RC4_128_SHA,
-}
-
-var (
-	defaultCipherSuitesLen = len(cipherSuitesPreferenceOrder) - len(disabledCipherSuites)
-	defaultCipherSuites    = cipherSuitesPreferenceOrder[:defaultCipherSuitesLen]
-)
-
-// defaultCipherSuitesTLS13 is also the preference order, since there are no
-// disabled by default TLS 1.3 cipher suites. The same AES vs ChaCha20 logic as
-// cipherSuitesPreferenceOrder applies.
-var defaultCipherSuitesTLS13 = []uint16{
-	TLS_AES_128_GCM_SHA256,
-	TLS_AES_256_GCM_SHA384,
-	TLS_CHACHA20_POLY1305_SHA256,
-}
-
-var defaultCipherSuitesTLS13NoAES = []uint16{
-	TLS_CHACHA20_POLY1305_SHA256,
-	TLS_AES_128_GCM_SHA256,
-	TLS_AES_256_GCM_SHA384,
-}
-
-var (
-	hasGCMAsmAMD64 = cpu.X86.HasAES && cpu.X86.HasPCLMULQDQ
-	hasGCMAsmARM64 = cpu.ARM64.HasAES && cpu.ARM64.HasPMULL
-	// Keep in sync with crypto/aes/cipher_s390x.go.
-	hasGCMAsmS390X = cpu.S390X.HasAES && cpu.S390X.HasAESCBC && cpu.S390X.HasAESCTR &&
-		(cpu.S390X.HasGHASH || cpu.S390X.HasAESGCM)
-
-	hasAESGCMHardwareSupport = runtime.GOARCH == "amd64" && hasGCMAsmAMD64 ||
-		runtime.GOARCH == "arm64" && hasGCMAsmARM64 ||
-		runtime.GOARCH == "s390x" && hasGCMAsmS390X
-)
-
-var aesgcmCiphers = map[uint16]bool{
-	// TLS 1.2
-	TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256:   true,
-	TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384:   true,
-	TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256: true,
-	TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384: true,
-	// TLS 1.3
-	TLS_AES_128_GCM_SHA256: true,
-	TLS_AES_256_GCM_SHA384: true,
-}
-
-var nonAESGCMAEADCiphers = map[uint16]bool{
-	// TLS 1.2
-	TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305:   true,
-	TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305: true,
-	// TLS 1.3
-	TLS_CHACHA20_POLY1305_SHA256: true,
-}
-
-// aesgcmPreferred returns whether the first known cipher in the preference list
-// is an AES-GCM cipher, implying the peer has hardware support for it.
-func aesgcmPreferred(ciphers []uint16) bool {
-	for _, cID := range ciphers {
-		if c := cipherSuiteByID(cID); c != nil {
-			return aesgcmCiphers[cID]
-		}
-		if c := cipherSuiteTLS13ByID(cID); c != nil {
-			return aesgcmCiphers[cID]
-		}
-	}
-	return false
-}
-
-func cipherRC4(key, iv []byte, isRead bool) any {
-	cipher, _ := rc4.NewCipher(key)
-	return cipher
-}
-
-func cipher3DES(key, iv []byte, isRead bool) any {
-	block, _ := des.NewTripleDESCipher(key)
-	if isRead {
-		return cipher.NewCBCDecrypter(block, iv)
-	}
-	return cipher.NewCBCEncrypter(block, iv)
-}
-
-func cipherAES(key, iv []byte, isRead bool) any {
-	block, _ := aes.NewCipher(key)
-	if isRead {
-		return cipher.NewCBCDecrypter(block, iv)
-	}
-	return cipher.NewCBCEncrypter(block, iv)
-}
-
-// macSHA1 returns a SHA-1 based constant time MAC.
-func macSHA1(key []byte) hash.Hash {
-	return hmac.New(newConstantTimeHash(sha1.New), key)
-}
-
-// macSHA256 returns a SHA-256 based MAC. This is only supported in TLS 1.2 and
-// is currently only used in disabled-by-default cipher suites.
-func macSHA256(key []byte) hash.Hash {
-	return hmac.New(sha256.New, key)
-}
-
-type aead interface {
-	cipher.AEAD
-
-	// explicitNonceLen returns the number of bytes of explicit nonce
-	// included in each record. This is eight for older AEADs and
-	// zero for modern ones.
-	explicitNonceLen() int
-}
-
-const (
-	aeadNonceLength   = 12
-	noncePrefixLength = 4
-)
-
-// prefixNonceAEAD wraps an AEAD and prefixes a fixed portion of the nonce to
-// each call.
-type prefixNonceAEAD struct {
-	// nonce contains the fixed part of the nonce in the first four bytes.
-	nonce [aeadNonceLength]byte
-	aead  cipher.AEAD
-}
-
-func (f *prefixNonceAEAD) NonceSize() int        { return aeadNonceLength - noncePrefixLength }
-func (f *prefixNonceAEAD) Overhead() int         { return f.aead.Overhead() }
-func (f *prefixNonceAEAD) explicitNonceLen() int { return f.NonceSize() }
-
-func (f *prefixNonceAEAD) Seal(out, nonce, plaintext, additionalData []byte) []byte {
-	copy(f.nonce[4:], nonce)
-	return f.aead.Seal(out, f.nonce[:], plaintext, additionalData)
-}
-
-func (f *prefixNonceAEAD) Open(out, nonce, ciphertext, additionalData []byte) ([]byte, error) {
-	copy(f.nonce[4:], nonce)
-	return f.aead.Open(out, f.nonce[:], ciphertext, additionalData)
-}
-
-// xoredNonceAEAD wraps an AEAD by XORing in a fixed pattern to the nonce
-// before each call.
-type xorNonceAEAD struct {
-	nonceMask [aeadNonceLength]byte
-	aead      cipher.AEAD
-}
-
-func (f *xorNonceAEAD) NonceSize() int        { return 8 } // 64-bit sequence number
-func (f *xorNonceAEAD) Overhead() int         { return f.aead.Overhead() }
-func (f *xorNonceAEAD) explicitNonceLen() int { return 0 }
-
-func (f *xorNonceAEAD) Seal(out, nonce, plaintext, additionalData []byte) []byte {
-	for i, b := range nonce {
-		f.nonceMask[4+i] ^= b
-	}
-	result := f.aead.Seal(out, f.nonceMask[:], plaintext, additionalData)
-	for i, b := range nonce {
-		f.nonceMask[4+i] ^= b
-	}
-
-	return result
-}
-
-func (f *xorNonceAEAD) Open(out, nonce, ciphertext, additionalData []byte) ([]byte, error) {
-	for i, b := range nonce {
-		f.nonceMask[4+i] ^= b
-	}
-	result, err := f.aead.Open(out, f.nonceMask[:], ciphertext, additionalData)
-	for i, b := range nonce {
-		f.nonceMask[4+i] ^= b
-	}
-
-	return result, err
-}
-
-func aeadAESGCM(key, noncePrefix []byte) aead {
-	if len(noncePrefix) != noncePrefixLength {
-		panic("tls: internal error: wrong nonce length")
-	}
-	aes, err := aes.NewCipher(key)
-	if err != nil {
-		panic(err)
-	}
-	aead, err := cipher.NewGCM(aes)
-	if err != nil {
-		panic(err)
-	}
-
-	ret := &prefixNonceAEAD{aead: aead}
-	copy(ret.nonce[:], noncePrefix)
-	return ret
-}
-
-func aeadAESGCMTLS13(key, nonceMask []byte) aead {
-	if len(nonceMask) != aeadNonceLength {
-		panic("tls: internal error: wrong nonce length")
-	}
-	aes, err := aes.NewCipher(key)
-	if err != nil {
-		panic(err)
-	}
-	aead, err := cipher.NewGCM(aes)
-	if err != nil {
-		panic(err)
-	}
-
-	ret := &xorNonceAEAD{aead: aead}
-	copy(ret.nonceMask[:], nonceMask)
-	return ret
-}
-
-func aeadChaCha20Poly1305(key, nonceMask []byte) aead {
-	if len(nonceMask) != aeadNonceLength {
-		panic("tls: internal error: wrong nonce length")
-	}
-	aead, err := chacha20poly1305.New(key)
-	if err != nil {
-		panic(err)
-	}
-
-	ret := &xorNonceAEAD{aead: aead}
-	copy(ret.nonceMask[:], nonceMask)
-	return ret
-}
-
-type constantTimeHash interface {
-	hash.Hash
-	ConstantTimeSum(b []byte) []byte
-}
-
-// cthWrapper wraps any hash.Hash that implements ConstantTimeSum, and replaces
-// with that all calls to Sum. It's used to obtain a ConstantTimeSum-based HMAC.
-type cthWrapper struct {
-	h constantTimeHash
-}
-
-func (c *cthWrapper) Size() int                   { return c.h.Size() }
-func (c *cthWrapper) BlockSize() int              { return c.h.BlockSize() }
-func (c *cthWrapper) Reset()                      { c.h.Reset() }
-func (c *cthWrapper) Write(p []byte) (int, error) { return c.h.Write(p) }
-func (c *cthWrapper) Sum(b []byte) []byte         { return c.h.ConstantTimeSum(b) }
-
-func newConstantTimeHash(h func() hash.Hash) func() hash.Hash {
-	return func() hash.Hash {
-		return &cthWrapper{h().(constantTimeHash)}
-	}
-}
-
-// tls10MAC implements the TLS 1.0 MAC function. RFC 2246, Section 6.2.3.
-func tls10MAC(h hash.Hash, out, seq, header, data, extra []byte) []byte {
-	h.Reset()
-	h.Write(seq)
-	h.Write(header)
-	h.Write(data)
-	res := h.Sum(out)
-	if extra != nil {
-		h.Write(extra)
-	}
-	return res
-}
-
-func rsaKA(version uint16) keyAgreement {
-	return rsaKeyAgreement{}
-}
-
-func ecdheECDSAKA(version uint16) keyAgreement {
-	return &ecdheKeyAgreement{
-		isRSA:   false,
-		version: version,
-	}
-}
-
-func ecdheRSAKA(version uint16) keyAgreement {
-	return &ecdheKeyAgreement{
-		isRSA:   true,
-		version: version,
-	}
-}
-
-// mutualCipherSuite returns a cipherSuite given a list of supported
-// ciphersuites and the id requested by the peer.
-func mutualCipherSuite(have []uint16, want uint16) *cipherSuite {
-	for _, id := range have {
-		if id == want {
-			return cipherSuiteByID(id)
-		}
-	}
-	return nil
-}
-
-func cipherSuiteByID(id uint16) *cipherSuite {
-	for _, cipherSuite := range cipherSuites {
-		if cipherSuite.id == id {
-			return cipherSuite
-		}
-	}
-	return nil
-}
-
-func mutualCipherSuiteTLS13(have []uint16, want uint16) *cipherSuiteTLS13 {
-	for _, id := range have {
-		if id == want {
-			return cipherSuiteTLS13ByID(id)
-		}
-	}
-	return nil
-}
-
-func cipherSuiteTLS13ByID(id uint16) *cipherSuiteTLS13 {
-	for _, cipherSuite := range cipherSuitesTLS13 {
-		if cipherSuite.id == id {
-			return cipherSuite
-		}
-	}
-	return nil
-}
-
-// A list of cipher suite IDs that are, or have been, implemented by this
-// package.
-//
-// See https://www.iana.org/assignments/tls-parameters/tls-parameters.xml
-const (
-	// TLS 1.0 - 1.2 cipher suites.
-	TLS_RSA_WITH_RC4_128_SHA                      uint16 = 0x0005
-	TLS_RSA_WITH_3DES_EDE_CBC_SHA                 uint16 = 0x000a
-	TLS_RSA_WITH_AES_128_CBC_SHA                  uint16 = 0x002f
-	TLS_RSA_WITH_AES_256_CBC_SHA                  uint16 = 0x0035
-	TLS_RSA_WITH_AES_128_CBC_SHA256               uint16 = 0x003c
-	TLS_RSA_WITH_AES_128_GCM_SHA256               uint16 = 0x009c
-	TLS_RSA_WITH_AES_256_GCM_SHA384               uint16 = 0x009d
-	TLS_ECDHE_ECDSA_WITH_RC4_128_SHA              uint16 = 0xc007
-	TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA          uint16 = 0xc009
-	TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA          uint16 = 0xc00a
-	TLS_ECDHE_RSA_WITH_RC4_128_SHA                uint16 = 0xc011
-	TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA           uint16 = 0xc012
-	TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA            uint16 = 0xc013
-	TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA            uint16 = 0xc014
-	TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256       uint16 = 0xc023
-	TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256         uint16 = 0xc027
-	TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256         uint16 = 0xc02f
-	TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256       uint16 = 0xc02b
-	TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384         uint16 = 0xc030
-	TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384       uint16 = 0xc02c
-	TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256   uint16 = 0xcca8
-	TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 uint16 = 0xcca9
-
-	// TLS 1.3 cipher suites.
-	TLS_AES_128_GCM_SHA256       uint16 = 0x1301
-	TLS_AES_256_GCM_SHA384       uint16 = 0x1302
-	TLS_CHACHA20_POLY1305_SHA256 uint16 = 0x1303
-
-	// TLS_FALLBACK_SCSV isn't a standard cipher suite but an indicator
-	// that the client is doing version fallback. See RFC 7507.
-	TLS_FALLBACK_SCSV uint16 = 0x5600
-
-	// Legacy names for the corresponding cipher suites with the correct _SHA256
-	// suffix, retained for backward compatibility.
-	TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305   = TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256
-	TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305 = TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256
-)
diff --git a/contrib/go/_std_1.18/src/crypto/tls/common.go b/contrib/go/_std_1.18/src/crypto/tls/common.go
deleted file mode 100644
index e6e7598ce9..0000000000
--- a/contrib/go/_std_1.18/src/crypto/tls/common.go
+++ /dev/null
@@ -1,1480 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package tls
-
-import (
-	"bytes"
-	"container/list"
-	"context"
-	"crypto"
-	"crypto/ecdsa"
-	"crypto/ed25519"
-	"crypto/elliptic"
-	"crypto/rand"
-	"crypto/rsa"
-	"crypto/sha512"
-	"crypto/x509"
-	"errors"
-	"fmt"
-	"internal/godebug"
-	"io"
-	"net"
-	"strings"
-	"sync"
-	"time"
-)
-
-const (
-	VersionTLS10 = 0x0301
-	VersionTLS11 = 0x0302
-	VersionTLS12 = 0x0303
-	VersionTLS13 = 0x0304
-
-	// Deprecated: SSLv3 is cryptographically broken, and is no longer
-	// supported by this package. See golang.org/issue/32716.
-	VersionSSL30 = 0x0300
-)
-
-const (
-	maxPlaintext       = 16384        // maximum plaintext payload length
-	maxCiphertext      = 16384 + 2048 // maximum ciphertext payload length
-	maxCiphertextTLS13 = 16384 + 256  // maximum ciphertext length in TLS 1.3
-	recordHeaderLen    = 5            // record header length
-	maxHandshake       = 65536        // maximum handshake we support (protocol max is 16 MB)
-	maxUselessRecords  = 16           // maximum number of consecutive non-advancing records
-)
-
-// TLS record types.
-type recordType uint8
-
-const (
-	recordTypeChangeCipherSpec recordType = 20
-	recordTypeAlert            recordType = 21
-	recordTypeHandshake        recordType = 22
-	recordTypeApplicationData  recordType = 23
-)
-
-// TLS handshake message types.
-const (
-	typeHelloRequest        uint8 = 0
-	typeClientHello         uint8 = 1
-	typeServerHello         uint8 = 2
-	typeNewSessionTicket    uint8 = 4
-	typeEndOfEarlyData      uint8 = 5
-	typeEncryptedExtensions uint8 = 8
-	typeCertificate         uint8 = 11
-	typeServerKeyExchange   uint8 = 12
-	typeCertificateRequest  uint8 = 13
-	typeServerHelloDone     uint8 = 14
-	typeCertificateVerify   uint8 = 15
-	typeClientKeyExchange   uint8 = 16
-	typeFinished            uint8 = 20
-	typeCertificateStatus   uint8 = 22
-	typeKeyUpdate           uint8 = 24
-	typeNextProtocol        uint8 = 67  // Not IANA assigned
-	typeMessageHash         uint8 = 254 // synthetic message
-)
-
-// TLS compression types.
-const (
-	compressionNone uint8 = 0
-)
-
-// TLS extension numbers
-const (
-	extensionServerName              uint16 = 0
-	extensionStatusRequest           uint16 = 5
-	extensionSupportedCurves         uint16 = 10 // supported_groups in TLS 1.3, see RFC 8446, Section 4.2.7
-	extensionSupportedPoints         uint16 = 11
-	extensionSignatureAlgorithms     uint16 = 13
-	extensionALPN                    uint16 = 16
-	extensionSCT                     uint16 = 18
-	extensionSessionTicket           uint16 = 35
-	extensionPreSharedKey            uint16 = 41
-	extensionEarlyData               uint16 = 42
-	extensionSupportedVersions       uint16 = 43
-	extensionCookie                  uint16 = 44
-	extensionPSKModes                uint16 = 45
-	extensionCertificateAuthorities  uint16 = 47
-	extensionSignatureAlgorithmsCert uint16 = 50
-	extensionKeyShare                uint16 = 51
-	extensionRenegotiationInfo       uint16 = 0xff01
-)
-
-// TLS signaling cipher suite values
-const (
-	scsvRenegotiation uint16 = 0x00ff
-)
-
-// CurveID is the type of a TLS identifier for an elliptic curve. See
-// https://www.iana.org/assignments/tls-parameters/tls-parameters.xml#tls-parameters-8.
-//
-// In TLS 1.3, this type is called NamedGroup, but at this time this library
-// only supports Elliptic Curve based groups. See RFC 8446, Section 4.2.7.
-type CurveID uint16
-
-const (
-	CurveP256 CurveID = 23
-	CurveP384 CurveID = 24
-	CurveP521 CurveID = 25
-	X25519    CurveID = 29
-)
-
-// TLS 1.3 Key Share. See RFC 8446, Section 4.2.8.
-type keyShare struct {
-	group CurveID
-	data  []byte
-}
-
-// TLS 1.3 PSK Key Exchange Modes. See RFC 8446, Section 4.2.9.
-const (
-	pskModePlain uint8 = 0
-	pskModeDHE   uint8 = 1
-)
-
-// TLS 1.3 PSK Identity. Can be a Session Ticket, or a reference to a saved
-// session. See RFC 8446, Section 4.2.11.
-type pskIdentity struct {
-	label               []byte
-	obfuscatedTicketAge uint32
-}
-
-// TLS Elliptic Curve Point Formats
-// https://www.iana.org/assignments/tls-parameters/tls-parameters.xml#tls-parameters-9
-const (
-	pointFormatUncompressed uint8 = 0
-)
-
-// TLS CertificateStatusType (RFC 3546)
-const (
-	statusTypeOCSP uint8 = 1
-)
-
-// Certificate types (for certificateRequestMsg)
-const (
-	certTypeRSASign   = 1
-	certTypeECDSASign = 64 // ECDSA or EdDSA keys, see RFC 8422, Section 3.
-)
-
-// Signature algorithms (for internal signaling use). Starting at 225 to avoid overlap with
-// TLS 1.2 codepoints (RFC 5246, Appendix A.4.1), with which these have nothing to do.
-const (
-	signaturePKCS1v15 uint8 = iota + 225
-	signatureRSAPSS
-	signatureECDSA
-	signatureEd25519
-)
-
-// directSigning is a standard Hash value that signals that no pre-hashing
-// should be performed, and that the input should be signed directly. It is the
-// hash function associated with the Ed25519 signature scheme.
-var directSigning crypto.Hash = 0
-
-// supportedSignatureAlgorithms contains the signature and hash algorithms that
-// the code advertises as supported in a TLS 1.2+ ClientHello and in a TLS 1.2+
-// CertificateRequest. The two fields are merged to match with TLS 1.3.
-// Note that in TLS 1.2, the ECDSA algorithms are not constrained to P-256, etc.
-var supportedSignatureAlgorithms = []SignatureScheme{
-	PSSWithSHA256,
-	ECDSAWithP256AndSHA256,
-	Ed25519,
-	PSSWithSHA384,
-	PSSWithSHA512,
-	PKCS1WithSHA256,
-	PKCS1WithSHA384,
-	PKCS1WithSHA512,
-	ECDSAWithP384AndSHA384,
-	ECDSAWithP521AndSHA512,
-	PKCS1WithSHA1,
-	ECDSAWithSHA1,
-}
-
-// helloRetryRequestRandom is set as the Random value of a ServerHello
-// to signal that the message is actually a HelloRetryRequest.
-var helloRetryRequestRandom = []byte{ // See RFC 8446, Section 4.1.3.
-	0xCF, 0x21, 0xAD, 0x74, 0xE5, 0x9A, 0x61, 0x11,
-	0xBE, 0x1D, 0x8C, 0x02, 0x1E, 0x65, 0xB8, 0x91,
-	0xC2, 0xA2, 0x11, 0x16, 0x7A, 0xBB, 0x8C, 0x5E,
-	0x07, 0x9E, 0x09, 0xE2, 0xC8, 0xA8, 0x33, 0x9C,
-}
-
-const (
-	// downgradeCanaryTLS12 or downgradeCanaryTLS11 is embedded in the server
-	// random as a downgrade protection if the server would be capable of
-	// negotiating a higher version. See RFC 8446, Section 4.1.3.
-	downgradeCanaryTLS12 = "DOWNGRD\x01"
-	downgradeCanaryTLS11 = "DOWNGRD\x00"
-)
-
-// testingOnlyForceDowngradeCanary is set in tests to force the server side to
-// include downgrade canaries even if it's using its highers supported version.
-var testingOnlyForceDowngradeCanary bool
-
-// ConnectionState records basic TLS details about the connection.
-type ConnectionState struct {
-	// Version is the TLS version used by the connection (e.g. VersionTLS12).
-	Version uint16
-
-	// HandshakeComplete is true if the handshake has concluded.
-	HandshakeComplete bool
-
-	// DidResume is true if this connection was successfully resumed from a
-	// previous session with a session ticket or similar mechanism.
-	DidResume bool
-
-	// CipherSuite is the cipher suite negotiated for the connection (e.g.
-	// TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256, TLS_AES_128_GCM_SHA256).
-	CipherSuite uint16
-
-	// NegotiatedProtocol is the application protocol negotiated with ALPN.
-	NegotiatedProtocol string
-
-	// NegotiatedProtocolIsMutual used to indicate a mutual NPN negotiation.
-	//
-	// Deprecated: this value is always true.
-	NegotiatedProtocolIsMutual bool
-
-	// ServerName is the value of the Server Name Indication extension sent by
-	// the client. It's available both on the server and on the client side.
-	ServerName string
-
-	// PeerCertificates are the parsed certificates sent by the peer, in the
-	// order in which they were sent. The first element is the leaf certificate
-	// that the connection is verified against.
-	//
-	// On the client side, it can't be empty. On the server side, it can be
-	// empty if Config.ClientAuth is not RequireAnyClientCert or
-	// RequireAndVerifyClientCert.
-	PeerCertificates []*x509.Certificate
-
-	// VerifiedChains is a list of one or more chains where the first element is
-	// PeerCertificates[0] and the last element is from Config.RootCAs (on the
-	// client side) or Config.ClientCAs (on the server side).
-	//
-	// On the client side, it's set if Config.InsecureSkipVerify is false. On
-	// the server side, it's set if Config.ClientAuth is VerifyClientCertIfGiven
-	// (and the peer provided a certificate) or RequireAndVerifyClientCert.
-	VerifiedChains [][]*x509.Certificate
-
-	// SignedCertificateTimestamps is a list of SCTs provided by the peer
-	// through the TLS handshake for the leaf certificate, if any.
-	SignedCertificateTimestamps [][]byte
-
-	// OCSPResponse is a stapled Online Certificate Status Protocol (OCSP)
-	// response provided by the peer for the leaf certificate, if any.
-	OCSPResponse []byte
-
-	// TLSUnique contains the "tls-unique" channel binding value (see RFC 5929,
-	// Section 3). This value will be nil for TLS 1.3 connections and for all
-	// resumed connections.
-	//
-	// Deprecated: there are conditions in which this value might not be unique
-	// to a connection. See the Security Considerations sections of RFC 5705 and
-	// RFC 7627, and https://mitls.org/pages/attacks/3SHAKE#channelbindings.
-	TLSUnique []byte
-
-	// ekm is a closure exposed via ExportKeyingMaterial.
-	ekm func(label string, context []byte, length int) ([]byte, error)
-}
-
-// ExportKeyingMaterial returns length bytes of exported key material in a new
-// slice as defined in RFC 5705. If context is nil, it is not used as part of
-// the seed. If the connection was set to allow renegotiation via
-// Config.Renegotiation, this function will return an error.
-func (cs *ConnectionState) ExportKeyingMaterial(label string, context []byte, length int) ([]byte, error) {
-	return cs.ekm(label, context, length)
-}
-
-// ClientAuthType declares the policy the server will follow for
-// TLS Client Authentication.
-type ClientAuthType int
-
-const (
-	// NoClientCert indicates that no client certificate should be requested
-	// during the handshake, and if any certificates are sent they will not
-	// be verified.
-	NoClientCert ClientAuthType = iota
-	// RequestClientCert indicates that a client certificate should be requested
-	// during the handshake, but does not require that the client send any
-	// certificates.
-	RequestClientCert
-	// RequireAnyClientCert indicates that a client certificate should be requested
-	// during the handshake, and that at least one certificate is required to be
-	// sent by the client, but that certificate is not required to be valid.
-	RequireAnyClientCert
-	// VerifyClientCertIfGiven indicates that a client certificate should be requested
-	// during the handshake, but does not require that the client sends a
-	// certificate. If the client does send a certificate it is required to be
-	// valid.
-	VerifyClientCertIfGiven
-	// RequireAndVerifyClientCert indicates that a client certificate should be requested
-	// during the handshake, and that at least one valid certificate is required
-	// to be sent by the client.
-	RequireAndVerifyClientCert
-)
-
-// requiresClientCert reports whether the ClientAuthType requires a client
-// certificate to be provided.
-func requiresClientCert(c ClientAuthType) bool {
-	switch c {
-	case RequireAnyClientCert, RequireAndVerifyClientCert:
-		return true
-	default:
-		return false
-	}
-}
-
-// ClientSessionState contains the state needed by clients to resume TLS
-// sessions.
-type ClientSessionState struct {
-	sessionTicket      []uint8               // Encrypted ticket used for session resumption with server
-	vers               uint16                // TLS version negotiated for the session
-	cipherSuite        uint16                // Ciphersuite negotiated for the session
-	masterSecret       []byte                // Full handshake MasterSecret, or TLS 1.3 resumption_master_secret
-	serverCertificates []*x509.Certificate   // Certificate chain presented by the server
-	verifiedChains     [][]*x509.Certificate // Certificate chains we built for verification
-	receivedAt         time.Time             // When the session ticket was received from the server
-	ocspResponse       []byte                // Stapled OCSP response presented by the server
-	scts               [][]byte              // SCTs presented by the server
-
-	// TLS 1.3 fields.
-	nonce  []byte    // Ticket nonce sent by the server, to derive PSK
-	useBy  time.Time // Expiration of the ticket lifetime as set by the server
-	ageAdd uint32    // Random obfuscation factor for sending the ticket age
-}
-
-// ClientSessionCache is a cache of ClientSessionState objects that can be used
-// by a client to resume a TLS session with a given server. ClientSessionCache
-// implementations should expect to be called concurrently from different
-// goroutines. Up to TLS 1.2, only ticket-based resumption is supported, not
-// SessionID-based resumption. In TLS 1.3 they were merged into PSK modes, which
-// are supported via this interface.
-type ClientSessionCache interface {
-	// Get searches for a ClientSessionState associated with the given key.
-	// On return, ok is true if one was found.
-	Get(sessionKey string) (session *ClientSessionState, ok bool)
-
-	// Put adds the ClientSessionState to the cache with the given key. It might
-	// get called multiple times in a connection if a TLS 1.3 server provides
-	// more than one session ticket. If called with a nil *ClientSessionState,
-	// it should remove the cache entry.
-	Put(sessionKey string, cs *ClientSessionState)
-}
-
-//go:generate stringer -type=SignatureScheme,CurveID,ClientAuthType -output=common_string.go
-
-// SignatureScheme identifies a signature algorithm supported by TLS. See
-// RFC 8446, Section 4.2.3.
-type SignatureScheme uint16
-
-const (
-	// RSASSA-PKCS1-v1_5 algorithms.
-	PKCS1WithSHA256 SignatureScheme = 0x0401
-	PKCS1WithSHA384 SignatureScheme = 0x0501
-	PKCS1WithSHA512 SignatureScheme = 0x0601
-
-	// RSASSA-PSS algorithms with public key OID rsaEncryption.
-	PSSWithSHA256 SignatureScheme = 0x0804
-	PSSWithSHA384 SignatureScheme = 0x0805
-	PSSWithSHA512 SignatureScheme = 0x0806
-
-	// ECDSA algorithms. Only constrained to a specific curve in TLS 1.3.
-	ECDSAWithP256AndSHA256 SignatureScheme = 0x0403
-	ECDSAWithP384AndSHA384 SignatureScheme = 0x0503
-	ECDSAWithP521AndSHA512 SignatureScheme = 0x0603
-
-	// EdDSA algorithms.
-	Ed25519 SignatureScheme = 0x0807
-
-	// Legacy signature and hash algorithms for TLS 1.2.
-	PKCS1WithSHA1 SignatureScheme = 0x0201
-	ECDSAWithSHA1 SignatureScheme = 0x0203
-)
-
-// ClientHelloInfo contains information from a ClientHello message in order to
-// guide application logic in the GetCertificate and GetConfigForClient callbacks.
-type ClientHelloInfo struct {
-	// CipherSuites lists the CipherSuites supported by the client (e.g.
-	// TLS_AES_128_GCM_SHA256, TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256).
-	CipherSuites []uint16
-
-	// ServerName indicates the name of the server requested by the client
-	// in order to support virtual hosting. ServerName is only set if the
-	// client is using SNI (see RFC 4366, Section 3.1).
-	ServerName string
-
-	// SupportedCurves lists the elliptic curves supported by the client.
-	// SupportedCurves is set only if the Supported Elliptic Curves
-	// Extension is being used (see RFC 4492, Section 5.1.1).
-	SupportedCurves []CurveID
-
-	// SupportedPoints lists the point formats supported by the client.
-	// SupportedPoints is set only if the Supported Point Formats Extension
-	// is being used (see RFC 4492, Section 5.1.2).
-	SupportedPoints []uint8
-
-	// SignatureSchemes lists the signature and hash schemes that the client
-	// is willing to verify. SignatureSchemes is set only if the Signature
-	// Algorithms Extension is being used (see RFC 5246, Section 7.4.1.4.1).
-	SignatureSchemes []SignatureScheme
-
-	// SupportedProtos lists the application protocols supported by the client.
-	// SupportedProtos is set only if the Application-Layer Protocol
-	// Negotiation Extension is being used (see RFC 7301, Section 3.1).
-	//
-	// Servers can select a protocol by setting Config.NextProtos in a
-	// GetConfigForClient return value.
-	SupportedProtos []string
-
-	// SupportedVersions lists the TLS versions supported by the client.
-	// For TLS versions less than 1.3, this is extrapolated from the max
-	// version advertised by the client, so values other than the greatest
-	// might be rejected if used.
-	SupportedVersions []uint16
-
-	// Conn is the underlying net.Conn for the connection. Do not read
-	// from, or write to, this connection; that will cause the TLS
-	// connection to fail.
-	Conn net.Conn
-
-	// config is embedded by the GetCertificate or GetConfigForClient caller,
-	// for use with SupportsCertificate.
-	config *Config
-
-	// ctx is the context of the handshake that is in progress.
-	ctx context.Context
-}
-
-// Context returns the context of the handshake that is in progress.
-// This context is a child of the context passed to HandshakeContext,
-// if any, and is canceled when the handshake concludes.
-func (c *ClientHelloInfo) Context() context.Context {
-	return c.ctx
-}
-
-// CertificateRequestInfo contains information from a server's
-// CertificateRequest message, which is used to demand a certificate and proof
-// of control from a client.
-type CertificateRequestInfo struct {
-	// AcceptableCAs contains zero or more, DER-encoded, X.501
-	// Distinguished Names. These are the names of root or intermediate CAs
-	// that the server wishes the returned certificate to be signed by. An
-	// empty slice indicates that the server has no preference.
-	AcceptableCAs [][]byte
-
-	// SignatureSchemes lists the signature schemes that the server is
-	// willing to verify.
-	SignatureSchemes []SignatureScheme
-
-	// Version is the TLS version that was negotiated for this connection.
-	Version uint16
-
-	// ctx is the context of the handshake that is in progress.
-	ctx context.Context
-}
-
-// Context returns the context of the handshake that is in progress.
-// This context is a child of the context passed to HandshakeContext,
-// if any, and is canceled when the handshake concludes.
-func (c *CertificateRequestInfo) Context() context.Context {
-	return c.ctx
-}
-
-// RenegotiationSupport enumerates the different levels of support for TLS
-// renegotiation. TLS renegotiation is the act of performing subsequent
-// handshakes on a connection after the first. This significantly complicates
-// the state machine and has been the source of numerous, subtle security
-// issues. Initiating a renegotiation is not supported, but support for
-// accepting renegotiation requests may be enabled.
-//
-// Even when enabled, the server may not change its identity between handshakes
-// (i.e. the leaf certificate must be the same). Additionally, concurrent
-// handshake and application data flow is not permitted so renegotiation can
-// only be used with protocols that synchronise with the renegotiation, such as
-// HTTPS.
-//
-// Renegotiation is not defined in TLS 1.3.
-type RenegotiationSupport int
-
-const (
-	// RenegotiateNever disables renegotiation.
-	RenegotiateNever RenegotiationSupport = iota
-
-	// RenegotiateOnceAsClient allows a remote server to request
-	// renegotiation once per connection.
-	RenegotiateOnceAsClient
-
-	// RenegotiateFreelyAsClient allows a remote server to repeatedly
-	// request renegotiation.
-	RenegotiateFreelyAsClient
-)
-
-// A Config structure is used to configure a TLS client or server.
-// After one has been passed to a TLS function it must not be
-// modified. A Config may be reused; the tls package will also not
-// modify it.
-type Config struct {
-	// Rand provides the source of entropy for nonces and RSA blinding.
-	// If Rand is nil, TLS uses the cryptographic random reader in package
-	// crypto/rand.
-	// The Reader must be safe for use by multiple goroutines.
-	Rand io.Reader
-
-	// Time returns the current time as the number of seconds since the epoch.
-	// If Time is nil, TLS uses time.Now.
-	Time func() time.Time
-
-	// Certificates contains one or more certificate chains to present to the
-	// other side of the connection. The first certificate compatible with the
-	// peer's requirements is selected automatically.
-	//
-	// Server configurations must set one of Certificates, GetCertificate or
-	// GetConfigForClient. Clients doing client-authentication may set either
-	// Certificates or GetClientCertificate.
-	//
-	// Note: if there are multiple Certificates, and they don't have the
-	// optional field Leaf set, certificate selection will incur a significant
-	// per-handshake performance cost.
-	Certificates []Certificate
-
-	// NameToCertificate maps from a certificate name to an element of
-	// Certificates. Note that a certificate name can be of the form
-	// '*.example.com' and so doesn't have to be a domain name as such.
-	//
-	// Deprecated: NameToCertificate only allows associating a single
-	// certificate with a given name. Leave this field nil to let the library
-	// select the first compatible chain from Certificates.
-	NameToCertificate map[string]*Certificate
-
-	// GetCertificate returns a Certificate based on the given
-	// ClientHelloInfo. It will only be called if the client supplies SNI
-	// information or if Certificates is empty.
-	//
-	// If GetCertificate is nil or returns nil, then the certificate is
-	// retrieved from NameToCertificate. If NameToCertificate is nil, the
-	// best element of Certificates will be used.
-	GetCertificate func(*ClientHelloInfo) (*Certificate, error)
-
-	// GetClientCertificate, if not nil, is called when a server requests a
-	// certificate from a client. If set, the contents of Certificates will
-	// be ignored.
-	//
-	// If GetClientCertificate returns an error, the handshake will be
-	// aborted and that error will be returned. Otherwise
-	// GetClientCertificate must return a non-nil Certificate. If
-	// Certificate.Certificate is empty then no certificate will be sent to
-	// the server. If this is unacceptable to the server then it may abort
-	// the handshake.
-	//
-	// GetClientCertificate may be called multiple times for the same
-	// connection if renegotiation occurs or if TLS 1.3 is in use.
-	GetClientCertificate func(*CertificateRequestInfo) (*Certificate, error)
-
-	// GetConfigForClient, if not nil, is called after a ClientHello is
-	// received from a client. It may return a non-nil Config in order to
-	// change the Config that will be used to handle this connection. If
-	// the returned Config is nil, the original Config will be used. The
-	// Config returned by this callback may not be subsequently modified.
-	//
-	// If GetConfigForClient is nil, the Config passed to Server() will be
-	// used for all connections.
-	//
-	// If SessionTicketKey was explicitly set on the returned Config, or if
-	// SetSessionTicketKeys was called on the returned Config, those keys will
-	// be used. Otherwise, the original Config keys will be used (and possibly
-	// rotated if they are automatically managed).
-	GetConfigForClient func(*ClientHelloInfo) (*Config, error)
-
-	// VerifyPeerCertificate, if not nil, is called after normal
-	// certificate verification by either a TLS client or server. It
-	// receives the raw ASN.1 certificates provided by the peer and also
-	// any verified chains that normal processing found. If it returns a
-	// non-nil error, the handshake is aborted and that error results.
-	//
-	// If normal verification fails then the handshake will abort before
-	// considering this callback. If normal verification is disabled by
-	// setting InsecureSkipVerify, or (for a server) when ClientAuth is
-	// RequestClientCert or RequireAnyClientCert, then this callback will
-	// be considered but the verifiedChains argument will always be nil.
-	VerifyPeerCertificate func(rawCerts [][]byte, verifiedChains [][]*x509.Certificate) error
-
-	// VerifyConnection, if not nil, is called after normal certificate
-	// verification and after VerifyPeerCertificate by either a TLS client
-	// or server. If it returns a non-nil error, the handshake is aborted
-	// and that error results.
-	//
-	// If normal verification fails then the handshake will abort before
-	// considering this callback. This callback will run for all connections
-	// regardless of InsecureSkipVerify or ClientAuth settings.
-	VerifyConnection func(ConnectionState) error
-
-	// RootCAs defines the set of root certificate authorities
-	// that clients use when verifying server certificates.
-	// If RootCAs is nil, TLS uses the host's root CA set.
-	RootCAs *x509.CertPool
-
-	// NextProtos is a list of supported application level protocols, in
-	// order of preference. If both peers support ALPN, the selected
-	// protocol will be one from this list, and the connection will fail
-	// if there is no mutually supported protocol. If NextProtos is empty
-	// or the peer doesn't support ALPN, the connection will succeed and
-	// ConnectionState.NegotiatedProtocol will be empty.
-	NextProtos []string
-
-	// ServerName is used to verify the hostname on the returned
-	// certificates unless InsecureSkipVerify is given. It is also included
-	// in the client's handshake to support virtual hosting unless it is
-	// an IP address.
-	ServerName string
-
-	// ClientAuth determines the server's policy for
-	// TLS Client Authentication. The default is NoClientCert.
-	ClientAuth ClientAuthType
-
-	// ClientCAs defines the set of root certificate authorities
-	// that servers use if required to verify a client certificate
-	// by the policy in ClientAuth.
-	ClientCAs *x509.CertPool
-
-	// InsecureSkipVerify controls whether a client verifies the server's
-	// certificate chain and host name. If InsecureSkipVerify is true, crypto/tls
-	// accepts any certificate presented by the server and any host name in that
-	// certificate. In this mode, TLS is susceptible to machine-in-the-middle
-	// attacks unless custom verification is used. This should be used only for
-	// testing or in combination with VerifyConnection or VerifyPeerCertificate.
-	InsecureSkipVerify bool
-
-	// CipherSuites is a list of enabled TLS 1.0–1.2 cipher suites. The order of
-	// the list is ignored. Note that TLS 1.3 ciphersuites are not configurable.
-	//
-	// If CipherSuites is nil, a safe default list is used. The default cipher
-	// suites might change over time.
-	CipherSuites []uint16
-
-	// PreferServerCipherSuites is a legacy field and has no effect.
-	//
-	// It used to control whether the server would follow the client's or the
-	// server's preference. Servers now select the best mutually supported
-	// cipher suite based on logic that takes into account inferred client
-	// hardware, server hardware, and security.
-	//
-	// Deprecated: PreferServerCipherSuites is ignored.
-	PreferServerCipherSuites bool
-
-	// SessionTicketsDisabled may be set to true to disable session ticket and
-	// PSK (resumption) support. Note that on clients, session ticket support is
-	// also disabled if ClientSessionCache is nil.
-	SessionTicketsDisabled bool
-
-	// SessionTicketKey is used by TLS servers to provide session resumption.
-	// See RFC 5077 and the PSK mode of RFC 8446. If zero, it will be filled
-	// with random data before the first server handshake.
-	//
-	// Deprecated: if this field is left at zero, session ticket keys will be
-	// automatically rotated every day and dropped after seven days. For
-	// customizing the rotation schedule or synchronizing servers that are
-	// terminating connections for the same host, use SetSessionTicketKeys.
-	SessionTicketKey [32]byte
-
-	// ClientSessionCache is a cache of ClientSessionState entries for TLS
-	// session resumption. It is only used by clients.
-	ClientSessionCache ClientSessionCache
-
-	// MinVersion contains the minimum TLS version that is acceptable.
-	//
-	// By default, TLS 1.2 is currently used as the minimum when acting as a
-	// client, and TLS 1.0 when acting as a server. TLS 1.0 is the minimum
-	// supported by this package, both as a client and as a server.
-	//
-	// The client-side default can temporarily be reverted to TLS 1.0 by
-	// including the value "x509sha1=1" in the GODEBUG environment variable.
-	// Note that this option will be removed in Go 1.19 (but it will still be
-	// possible to set this field to VersionTLS10 explicitly).
-	MinVersion uint16
-
-	// MaxVersion contains the maximum TLS version that is acceptable.
-	//
-	// By default, the maximum version supported by this package is used,
-	// which is currently TLS 1.3.
-	MaxVersion uint16
-
-	// CurvePreferences contains the elliptic curves that will be used in
-	// an ECDHE handshake, in preference order. If empty, the default will
-	// be used. The client will use the first preference as the type for
-	// its key share in TLS 1.3. This may change in the future.
-	CurvePreferences []CurveID
-
-	// DynamicRecordSizingDisabled disables adaptive sizing of TLS records.
-	// When true, the largest possible TLS record size is always used. When
-	// false, the size of TLS records may be adjusted in an attempt to
-	// improve latency.
-	DynamicRecordSizingDisabled bool
-
-	// Renegotiation controls what types of renegotiation are supported.
-	// The default, none, is correct for the vast majority of applications.
-	Renegotiation RenegotiationSupport
-
-	// KeyLogWriter optionally specifies a destination for TLS master secrets
-	// in NSS key log format that can be used to allow external programs
-	// such as Wireshark to decrypt TLS connections.
-	// See https://developer.mozilla.org/en-US/docs/Mozilla/Projects/NSS/Key_Log_Format.
-	// Use of KeyLogWriter compromises security and should only be
-	// used for debugging.
-	KeyLogWriter io.Writer
-
-	// mutex protects sessionTicketKeys and autoSessionTicketKeys.
-	mutex sync.RWMutex
-	// sessionTicketKeys contains zero or more ticket keys. If set, it means the
-	// the keys were set with SessionTicketKey or SetSessionTicketKeys. The
-	// first key is used for new tickets and any subsequent keys can be used to
-	// decrypt old tickets. The slice contents are not protected by the mutex
-	// and are immutable.
-	sessionTicketKeys []ticketKey
-	// autoSessionTicketKeys is like sessionTicketKeys but is owned by the
-	// auto-rotation logic. See Config.ticketKeys.
-	autoSessionTicketKeys []ticketKey
-}
-
-const (
-	// ticketKeyNameLen is the number of bytes of identifier that is prepended to
-	// an encrypted session ticket in order to identify the key used to encrypt it.
-	ticketKeyNameLen = 16
-
-	// ticketKeyLifetime is how long a ticket key remains valid and can be used to
-	// resume a client connection.
-	ticketKeyLifetime = 7 * 24 * time.Hour // 7 days
-
-	// ticketKeyRotation is how often the server should rotate the session ticket key
-	// that is used for new tickets.
-	ticketKeyRotation = 24 * time.Hour
-)
-
-// ticketKey is the internal representation of a session ticket key.
-type ticketKey struct {
-	// keyName is an opaque byte string that serves to identify the session
-	// ticket key. It's exposed as plaintext in every session ticket.
-	keyName [ticketKeyNameLen]byte
-	aesKey  [16]byte
-	hmacKey [16]byte
-	// created is the time at which this ticket key was created. See Config.ticketKeys.
-	created time.Time
-}
-
-// ticketKeyFromBytes converts from the external representation of a session
-// ticket key to a ticketKey. Externally, session ticket keys are 32 random
-// bytes and this function expands that into sufficient name and key material.
-func (c *Config) ticketKeyFromBytes(b [32]byte) (key ticketKey) {
-	hashed := sha512.Sum512(b[:])
-	copy(key.keyName[:], hashed[:ticketKeyNameLen])
-	copy(key.aesKey[:], hashed[ticketKeyNameLen:ticketKeyNameLen+16])
-	copy(key.hmacKey[:], hashed[ticketKeyNameLen+16:ticketKeyNameLen+32])
-	key.created = c.time()
-	return key
-}
-
-// maxSessionTicketLifetime is the maximum allowed lifetime of a TLS 1.3 session
-// ticket, and the lifetime we set for tickets we send.
-const maxSessionTicketLifetime = 7 * 24 * time.Hour
-
-// Clone returns a shallow clone of c or nil if c is nil. It is safe to clone a Config that is
-// being used concurrently by a TLS client or server.
-func (c *Config) Clone() *Config {
-	if c == nil {
-		return nil
-	}
-	c.mutex.RLock()
-	defer c.mutex.RUnlock()
-	return &Config{
-		Rand:                        c.Rand,
-		Time:                        c.Time,
-		Certificates:                c.Certificates,
-		NameToCertificate:           c.NameToCertificate,
-		GetCertificate:              c.GetCertificate,
-		GetClientCertificate:        c.GetClientCertificate,
-		GetConfigForClient:          c.GetConfigForClient,
-		VerifyPeerCertificate:       c.VerifyPeerCertificate,
-		VerifyConnection:            c.VerifyConnection,
-		RootCAs:                     c.RootCAs,
-		NextProtos:                  c.NextProtos,
-		ServerName:                  c.ServerName,
-		ClientAuth:                  c.ClientAuth,
-		ClientCAs:                   c.ClientCAs,
-		InsecureSkipVerify:          c.InsecureSkipVerify,
-		CipherSuites:                c.CipherSuites,
-		PreferServerCipherSuites:    c.PreferServerCipherSuites,
-		SessionTicketsDisabled:      c.SessionTicketsDisabled,
-		SessionTicketKey:            c.SessionTicketKey,
-		ClientSessionCache:          c.ClientSessionCache,
-		MinVersion:                  c.MinVersion,
-		MaxVersion:                  c.MaxVersion,
-		CurvePreferences:            c.CurvePreferences,
-		DynamicRecordSizingDisabled: c.DynamicRecordSizingDisabled,
-		Renegotiation:               c.Renegotiation,
-		KeyLogWriter:                c.KeyLogWriter,
-		sessionTicketKeys:           c.sessionTicketKeys,
-		autoSessionTicketKeys:       c.autoSessionTicketKeys,
-	}
-}
-
-// deprecatedSessionTicketKey is set as the prefix of SessionTicketKey if it was
-// randomized for backwards compatibility but is not in use.
-var deprecatedSessionTicketKey = []byte("DEPRECATED")
-
-// initLegacySessionTicketKeyRLocked ensures the legacy SessionTicketKey field is
-// randomized if empty, and that sessionTicketKeys is populated from it otherwise.
-func (c *Config) initLegacySessionTicketKeyRLocked() {
-	// Don't write if SessionTicketKey is already defined as our deprecated string,
-	// or if it is defined by the user but sessionTicketKeys is already set.
-	if c.SessionTicketKey != [32]byte{} &&
-		(bytes.HasPrefix(c.SessionTicketKey[:], deprecatedSessionTicketKey) || len(c.sessionTicketKeys) > 0) {
-		return
-	}
-
-	// We need to write some data, so get an exclusive lock and re-check any conditions.
-	c.mutex.RUnlock()
-	defer c.mutex.RLock()
-	c.mutex.Lock()
-	defer c.mutex.Unlock()
-	if c.SessionTicketKey == [32]byte{} {
-		if _, err := io.ReadFull(c.rand(), c.SessionTicketKey[:]); err != nil {
-			panic(fmt.Sprintf("tls: unable to generate random session ticket key: %v", err))
-		}
-		// Write the deprecated prefix at the beginning so we know we created
-		// it. This key with the DEPRECATED prefix isn't used as an actual
-		// session ticket key, and is only randomized in case the application
-		// reuses it for some reason.
-		copy(c.SessionTicketKey[:], deprecatedSessionTicketKey)
-	} else if !bytes.HasPrefix(c.SessionTicketKey[:], deprecatedSessionTicketKey) && len(c.sessionTicketKeys) == 0 {
-		c.sessionTicketKeys = []ticketKey{c.ticketKeyFromBytes(c.SessionTicketKey)}
-	}
-
-}
-
-// ticketKeys returns the ticketKeys for this connection.
-// If configForClient has explicitly set keys, those will
-// be returned. Otherwise, the keys on c will be used and
-// may be rotated if auto-managed.
-// During rotation, any expired session ticket keys are deleted from
-// c.sessionTicketKeys. If the session ticket key that is currently
-// encrypting tickets (ie. the first ticketKey in c.sessionTicketKeys)
-// is not fresh, then a new session ticket key will be
-// created and prepended to c.sessionTicketKeys.
-func (c *Config) ticketKeys(configForClient *Config) []ticketKey {
-	// If the ConfigForClient callback returned a Config with explicitly set
-	// keys, use those, otherwise just use the original Config.
-	if configForClient != nil {
-		configForClient.mutex.RLock()
-		if configForClient.SessionTicketsDisabled {
-			return nil
-		}
-		configForClient.initLegacySessionTicketKeyRLocked()
-		if len(configForClient.sessionTicketKeys) != 0 {
-			ret := configForClient.sessionTicketKeys
-			configForClient.mutex.RUnlock()
-			return ret
-		}
-		configForClient.mutex.RUnlock()
-	}
-
-	c.mutex.RLock()
-	defer c.mutex.RUnlock()
-	if c.SessionTicketsDisabled {
-		return nil
-	}
-	c.initLegacySessionTicketKeyRLocked()
-	if len(c.sessionTicketKeys) != 0 {
-		return c.sessionTicketKeys
-	}
-	// Fast path for the common case where the key is fresh enough.
-	if len(c.autoSessionTicketKeys) > 0 && c.time().Sub(c.autoSessionTicketKeys[0].created) < ticketKeyRotation {
-		return c.autoSessionTicketKeys
-	}
-
-	// autoSessionTicketKeys are managed by auto-rotation.
-	c.mutex.RUnlock()
-	defer c.mutex.RLock()
-	c.mutex.Lock()
-	defer c.mutex.Unlock()
-	// Re-check the condition in case it changed since obtaining the new lock.
-	if len(c.autoSessionTicketKeys) == 0 || c.time().Sub(c.autoSessionTicketKeys[0].created) >= ticketKeyRotation {
-		var newKey [32]byte
-		if _, err := io.ReadFull(c.rand(), newKey[:]); err != nil {
-			panic(fmt.Sprintf("unable to generate random session ticket key: %v", err))
-		}
-		valid := make([]ticketKey, 0, len(c.autoSessionTicketKeys)+1)
-		valid = append(valid, c.ticketKeyFromBytes(newKey))
-		for _, k := range c.autoSessionTicketKeys {
-			// While rotating the current key, also remove any expired ones.
-			if c.time().Sub(k.created) < ticketKeyLifetime {
-				valid = append(valid, k)
-			}
-		}
-		c.autoSessionTicketKeys = valid
-	}
-	return c.autoSessionTicketKeys
-}
-
-// SetSessionTicketKeys updates the session ticket keys for a server.
-//
-// The first key will be used when creating new tickets, while all keys can be
-// used for decrypting tickets. It is safe to call this function while the
-// server is running in order to rotate the session ticket keys. The function
-// will panic if keys is empty.
-//
-// Calling this function will turn off automatic session ticket key rotation.
-//
-// If multiple servers are terminating connections for the same host they should
-// all have the same session ticket keys. If the session ticket keys leaks,
-// previously recorded and future TLS connections using those keys might be
-// compromised.
-func (c *Config) SetSessionTicketKeys(keys [][32]byte) {
-	if len(keys) == 0 {
-		panic("tls: keys must have at least one key")
-	}
-
-	newKeys := make([]ticketKey, len(keys))
-	for i, bytes := range keys {
-		newKeys[i] = c.ticketKeyFromBytes(bytes)
-	}
-
-	c.mutex.Lock()
-	c.sessionTicketKeys = newKeys
-	c.mutex.Unlock()
-}
-
-func (c *Config) rand() io.Reader {
-	r := c.Rand
-	if r == nil {
-		return rand.Reader
-	}
-	return r
-}
-
-func (c *Config) time() time.Time {
-	t := c.Time
-	if t == nil {
-		t = time.Now
-	}
-	return t()
-}
-
-func (c *Config) cipherSuites() []uint16 {
-	if c.CipherSuites != nil {
-		return c.CipherSuites
-	}
-	return defaultCipherSuites
-}
-
-var supportedVersions = []uint16{
-	VersionTLS13,
-	VersionTLS12,
-	VersionTLS11,
-	VersionTLS10,
-}
-
-// debugEnableTLS10 enables TLS 1.0. See issue 45428.
-var debugEnableTLS10 = godebug.Get("tls10default") == "1"
-
-// roleClient and roleServer are meant to call supportedVersions and parents
-// with more readability at the callsite.
-const roleClient = true
-const roleServer = false
-
-func (c *Config) supportedVersions(isClient bool) []uint16 {
-	versions := make([]uint16, 0, len(supportedVersions))
-	for _, v := range supportedVersions {
-		if (c == nil || c.MinVersion == 0) && !debugEnableTLS10 &&
-			isClient && v < VersionTLS12 {
-			continue
-		}
-		if c != nil && c.MinVersion != 0 && v < c.MinVersion {
-			continue
-		}
-		if c != nil && c.MaxVersion != 0 && v > c.MaxVersion {
-			continue
-		}
-		versions = append(versions, v)
-	}
-	return versions
-}
-
-func (c *Config) maxSupportedVersion(isClient bool) uint16 {
-	supportedVersions := c.supportedVersions(isClient)
-	if len(supportedVersions) == 0 {
-		return 0
-	}
-	return supportedVersions[0]
-}
-
-// supportedVersionsFromMax returns a list of supported versions derived from a
-// legacy maximum version value. Note that only versions supported by this
-// library are returned. Any newer peer will use supportedVersions anyway.
-func supportedVersionsFromMax(maxVersion uint16) []uint16 {
-	versions := make([]uint16, 0, len(supportedVersions))
-	for _, v := range supportedVersions {
-		if v > maxVersion {
-			continue
-		}
-		versions = append(versions, v)
-	}
-	return versions
-}
-
-var defaultCurvePreferences = []CurveID{X25519, CurveP256, CurveP384, CurveP521}
-
-func (c *Config) curvePreferences() []CurveID {
-	if c == nil || len(c.CurvePreferences) == 0 {
-		return defaultCurvePreferences
-	}
-	return c.CurvePreferences
-}
-
-func (c *Config) supportsCurve(curve CurveID) bool {
-	for _, cc := range c.curvePreferences() {
-		if cc == curve {
-			return true
-		}
-	}
-	return false
-}
-
-// mutualVersion returns the protocol version to use given the advertised
-// versions of the peer. Priority is given to the peer preference order.
-func (c *Config) mutualVersion(isClient bool, peerVersions []uint16) (uint16, bool) {
-	supportedVersions := c.supportedVersions(isClient)
-	for _, peerVersion := range peerVersions {
-		for _, v := range supportedVersions {
-			if v == peerVersion {
-				return v, true
-			}
-		}
-	}
-	return 0, false
-}
-
-var errNoCertificates = errors.New("tls: no certificates configured")
-
-// getCertificate returns the best certificate for the given ClientHelloInfo,
-// defaulting to the first element of c.Certificates.
-func (c *Config) getCertificate(clientHello *ClientHelloInfo) (*Certificate, error) {
-	if c.GetCertificate != nil &&
-		(len(c.Certificates) == 0 || len(clientHello.ServerName) > 0) {
-		cert, err := c.GetCertificate(clientHello)
-		if cert != nil || err != nil {
-			return cert, err
-		}
-	}
-
-	if len(c.Certificates) == 0 {
-		return nil, errNoCertificates
-	}
-
-	if len(c.Certificates) == 1 {
-		// There's only one choice, so no point doing any work.
-		return &c.Certificates[0], nil
-	}
-
-	if c.NameToCertificate != nil {
-		name := strings.ToLower(clientHello.ServerName)
-		if cert, ok := c.NameToCertificate[name]; ok {
-			return cert, nil
-		}
-		if len(name) > 0 {
-			labels := strings.Split(name, ".")
-			labels[0] = "*"
-			wildcardName := strings.Join(labels, ".")
-			if cert, ok := c.NameToCertificate[wildcardName]; ok {
-				return cert, nil
-			}
-		}
-	}
-
-	for _, cert := range c.Certificates {
-		if err := clientHello.SupportsCertificate(&cert); err == nil {
-			return &cert, nil
-		}
-	}
-
-	// If nothing matches, return the first certificate.
-	return &c.Certificates[0], nil
-}
-
-// SupportsCertificate returns nil if the provided certificate is supported by
-// the client that sent the ClientHello. Otherwise, it returns an error
-// describing the reason for the incompatibility.
-//
-// If this ClientHelloInfo was passed to a GetConfigForClient or GetCertificate
-// callback, this method will take into account the associated Config. Note that
-// if GetConfigForClient returns a different Config, the change can't be
-// accounted for by this method.
-//
-// This function will call x509.ParseCertificate unless c.Leaf is set, which can
-// incur a significant performance cost.
-func (chi *ClientHelloInfo) SupportsCertificate(c *Certificate) error {
-	// Note we don't currently support certificate_authorities nor
-	// signature_algorithms_cert, and don't check the algorithms of the
-	// signatures on the chain (which anyway are a SHOULD, see RFC 8446,
-	// Section 4.4.2.2).
-
-	config := chi.config
-	if config == nil {
-		config = &Config{}
-	}
-	vers, ok := config.mutualVersion(roleServer, chi.SupportedVersions)
-	if !ok {
-		return errors.New("no mutually supported protocol versions")
-	}
-
-	// If the client specified the name they are trying to connect to, the
-	// certificate needs to be valid for it.
-	if chi.ServerName != "" {
-		x509Cert, err := c.leaf()
-		if err != nil {
-			return fmt.Errorf("failed to parse certificate: %w", err)
-		}
-		if err := x509Cert.VerifyHostname(chi.ServerName); err != nil {
-			return fmt.Errorf("certificate is not valid for requested server name: %w", err)
-		}
-	}
-
-	// supportsRSAFallback returns nil if the certificate and connection support
-	// the static RSA key exchange, and unsupported otherwise. The logic for
-	// supporting static RSA is completely disjoint from the logic for
-	// supporting signed key exchanges, so we just check it as a fallback.
-	supportsRSAFallback := func(unsupported error) error {
-		// TLS 1.3 dropped support for the static RSA key exchange.
-		if vers == VersionTLS13 {
-			return unsupported
-		}
-		// The static RSA key exchange works by decrypting a challenge with the
-		// RSA private key, not by signing, so check the PrivateKey implements
-		// crypto.Decrypter, like *rsa.PrivateKey does.
-		if priv, ok := c.PrivateKey.(crypto.Decrypter); ok {
-			if _, ok := priv.Public().(*rsa.PublicKey); !ok {
-				return unsupported
-			}
-		} else {
-			return unsupported
-		}
-		// Finally, there needs to be a mutual cipher suite that uses the static
-		// RSA key exchange instead of ECDHE.
-		rsaCipherSuite := selectCipherSuite(chi.CipherSuites, config.cipherSuites(), func(c *cipherSuite) bool {
-			if c.flags&suiteECDHE != 0 {
-				return false
-			}
-			if vers < VersionTLS12 && c.flags&suiteTLS12 != 0 {
-				return false
-			}
-			return true
-		})
-		if rsaCipherSuite == nil {
-			return unsupported
-		}
-		return nil
-	}
-
-	// If the client sent the signature_algorithms extension, ensure it supports
-	// schemes we can use with this certificate and TLS version.
-	if len(chi.SignatureSchemes) > 0 {
-		if _, err := selectSignatureScheme(vers, c, chi.SignatureSchemes); err != nil {
-			return supportsRSAFallback(err)
-		}
-	}
-
-	// In TLS 1.3 we are done because supported_groups is only relevant to the
-	// ECDHE computation, point format negotiation is removed, cipher suites are
-	// only relevant to the AEAD choice, and static RSA does not exist.
-	if vers == VersionTLS13 {
-		return nil
-	}
-
-	// The only signed key exchange we support is ECDHE.
-	if !supportsECDHE(config, chi.SupportedCurves, chi.SupportedPoints) {
-		return supportsRSAFallback(errors.New("client doesn't support ECDHE, can only use legacy RSA key exchange"))
-	}
-
-	var ecdsaCipherSuite bool
-	if priv, ok := c.PrivateKey.(crypto.Signer); ok {
-		switch pub := priv.Public().(type) {
-		case *ecdsa.PublicKey:
-			var curve CurveID
-			switch pub.Curve {
-			case elliptic.P256():
-				curve = CurveP256
-			case elliptic.P384():
-				curve = CurveP384
-			case elliptic.P521():
-				curve = CurveP521
-			default:
-				return supportsRSAFallback(unsupportedCertificateError(c))
-			}
-			var curveOk bool
-			for _, c := range chi.SupportedCurves {
-				if c == curve && config.supportsCurve(c) {
-					curveOk = true
-					break
-				}
-			}
-			if !curveOk {
-				return errors.New("client doesn't support certificate curve")
-			}
-			ecdsaCipherSuite = true
-		case ed25519.PublicKey:
-			if vers < VersionTLS12 || len(chi.SignatureSchemes) == 0 {
-				return errors.New("connection doesn't support Ed25519")
-			}
-			ecdsaCipherSuite = true
-		case *rsa.PublicKey:
-		default:
-			return supportsRSAFallback(unsupportedCertificateError(c))
-		}
-	} else {
-		return supportsRSAFallback(unsupportedCertificateError(c))
-	}
-
-	// Make sure that there is a mutually supported cipher suite that works with
-	// this certificate. Cipher suite selection will then apply the logic in
-	// reverse to pick it. See also serverHandshakeState.cipherSuiteOk.
-	cipherSuite := selectCipherSuite(chi.CipherSuites, config.cipherSuites(), func(c *cipherSuite) bool {
-		if c.flags&suiteECDHE == 0 {
-			return false
-		}
-		if c.flags&suiteECSign != 0 {
-			if !ecdsaCipherSuite {
-				return false
-			}
-		} else {
-			if ecdsaCipherSuite {
-				return false
-			}
-		}
-		if vers < VersionTLS12 && c.flags&suiteTLS12 != 0 {
-			return false
-		}
-		return true
-	})
-	if cipherSuite == nil {
-		return supportsRSAFallback(errors.New("client doesn't support any cipher suites compatible with the certificate"))
-	}
-
-	return nil
-}
-
-// SupportsCertificate returns nil if the provided certificate is supported by
-// the server that sent the CertificateRequest. Otherwise, it returns an error
-// describing the reason for the incompatibility.
-func (cri *CertificateRequestInfo) SupportsCertificate(c *Certificate) error {
-	if _, err := selectSignatureScheme(cri.Version, c, cri.SignatureSchemes); err != nil {
-		return err
-	}
-
-	if len(cri.AcceptableCAs) == 0 {
-		return nil
-	}
-
-	for j, cert := range c.Certificate {
-		x509Cert := c.Leaf
-		// Parse the certificate if this isn't the leaf node, or if
-		// chain.Leaf was nil.
-		if j != 0 || x509Cert == nil {
-			var err error
-			if x509Cert, err = x509.ParseCertificate(cert); err != nil {
-				return fmt.Errorf("failed to parse certificate #%d in the chain: %w", j, err)
-			}
-		}
-
-		for _, ca := range cri.AcceptableCAs {
-			if bytes.Equal(x509Cert.RawIssuer, ca) {
-				return nil
-			}
-		}
-	}
-	return errors.New("chain is not signed by an acceptable CA")
-}
-
-// BuildNameToCertificate parses c.Certificates and builds c.NameToCertificate
-// from the CommonName and SubjectAlternateName fields of each of the leaf
-// certificates.
-//
-// Deprecated: NameToCertificate only allows associating a single certificate
-// with a given name. Leave that field nil to let the library select the first
-// compatible chain from Certificates.
-func (c *Config) BuildNameToCertificate() {
-	c.NameToCertificate = make(map[string]*Certificate)
-	for i := range c.Certificates {
-		cert := &c.Certificates[i]
-		x509Cert, err := cert.leaf()
-		if err != nil {
-			continue
-		}
-		// If SANs are *not* present, some clients will consider the certificate
-		// valid for the name in the Common Name.
-		if x509Cert.Subject.CommonName != "" && len(x509Cert.DNSNames) == 0 {
-			c.NameToCertificate[x509Cert.Subject.CommonName] = cert
-		}
-		for _, san := range x509Cert.DNSNames {
-			c.NameToCertificate[san] = cert
-		}
-	}
-}
-
-const (
-	keyLogLabelTLS12           = "CLIENT_RANDOM"
-	keyLogLabelClientHandshake = "CLIENT_HANDSHAKE_TRAFFIC_SECRET"
-	keyLogLabelServerHandshake = "SERVER_HANDSHAKE_TRAFFIC_SECRET"
-	keyLogLabelClientTraffic   = "CLIENT_TRAFFIC_SECRET_0"
-	keyLogLabelServerTraffic   = "SERVER_TRAFFIC_SECRET_0"
-)
-
-func (c *Config) writeKeyLog(label string, clientRandom, secret []byte) error {
-	if c.KeyLogWriter == nil {
-		return nil
-	}
-
-	logLine := []byte(fmt.Sprintf("%s %x %x\n", label, clientRandom, secret))
-
-	writerMutex.Lock()
-	_, err := c.KeyLogWriter.Write(logLine)
-	writerMutex.Unlock()
-
-	return err
-}
-
-// writerMutex protects all KeyLogWriters globally. It is rarely enabled,
-// and is only for debugging, so a global mutex saves space.
-var writerMutex sync.Mutex
-
-// A Certificate is a chain of one or more certificates, leaf first.
-type Certificate struct {
-	Certificate [][]byte
-	// PrivateKey contains the private key corresponding to the public key in
-	// Leaf. This must implement crypto.Signer with an RSA, ECDSA or Ed25519 PublicKey.
-	// For a server up to TLS 1.2, it can also implement crypto.Decrypter with
-	// an RSA PublicKey.
-	PrivateKey crypto.PrivateKey
-	// SupportedSignatureAlgorithms is an optional list restricting what
-	// signature algorithms the PrivateKey can be used for.
-	SupportedSignatureAlgorithms []SignatureScheme
-	// OCSPStaple contains an optional OCSP response which will be served
-	// to clients that request it.
-	OCSPStaple []byte
-	// SignedCertificateTimestamps contains an optional list of Signed
-	// Certificate Timestamps which will be served to clients that request it.
-	SignedCertificateTimestamps [][]byte
-	// Leaf is the parsed form of the leaf certificate, which may be initialized
-	// using x509.ParseCertificate to reduce per-handshake processing. If nil,
-	// the leaf certificate will be parsed as needed.
-	Leaf *x509.Certificate
-}
-
-// leaf returns the parsed leaf certificate, either from c.Leaf or by parsing
-// the corresponding c.Certificate[0].
-func (c *Certificate) leaf() (*x509.Certificate, error) {
-	if c.Leaf != nil {
-		return c.Leaf, nil
-	}
-	return x509.ParseCertificate(c.Certificate[0])
-}
-
-type handshakeMessage interface {
-	marshal() []byte
-	unmarshal([]byte) bool
-}
-
-// lruSessionCache is a ClientSessionCache implementation that uses an LRU
-// caching strategy.
-type lruSessionCache struct {
-	sync.Mutex
-
-	m        map[string]*list.Element
-	q        *list.List
-	capacity int
-}
-
-type lruSessionCacheEntry struct {
-	sessionKey string
-	state      *ClientSessionState
-}
-
-// NewLRUClientSessionCache returns a ClientSessionCache with the given
-// capacity that uses an LRU strategy. If capacity is < 1, a default capacity
-// is used instead.
-func NewLRUClientSessionCache(capacity int) ClientSessionCache {
-	const defaultSessionCacheCapacity = 64
-
-	if capacity < 1 {
-		capacity = defaultSessionCacheCapacity
-	}
-	return &lruSessionCache{
-		m:        make(map[string]*list.Element),
-		q:        list.New(),
-		capacity: capacity,
-	}
-}
-
-// Put adds the provided (sessionKey, cs) pair to the cache. If cs is nil, the entry
-// corresponding to sessionKey is removed from the cache instead.
-func (c *lruSessionCache) Put(sessionKey string, cs *ClientSessionState) {
-	c.Lock()
-	defer c.Unlock()
-
-	if elem, ok := c.m[sessionKey]; ok {
-		if cs == nil {
-			c.q.Remove(elem)
-			delete(c.m, sessionKey)
-		} else {
-			entry := elem.Value.(*lruSessionCacheEntry)
-			entry.state = cs
-			c.q.MoveToFront(elem)
-		}
-		return
-	}
-
-	if c.q.Len() < c.capacity {
-		entry := &lruSessionCacheEntry{sessionKey, cs}
-		c.m[sessionKey] = c.q.PushFront(entry)
-		return
-	}
-
-	elem := c.q.Back()
-	entry := elem.Value.(*lruSessionCacheEntry)
-	delete(c.m, entry.sessionKey)
-	entry.sessionKey = sessionKey
-	entry.state = cs
-	c.q.MoveToFront(elem)
-	c.m[sessionKey] = elem
-}
-
-// Get returns the ClientSessionState value associated with a given key. It
-// returns (nil, false) if no value is found.
-func (c *lruSessionCache) Get(sessionKey string) (*ClientSessionState, bool) {
-	c.Lock()
-	defer c.Unlock()
-
-	if elem, ok := c.m[sessionKey]; ok {
-		c.q.MoveToFront(elem)
-		return elem.Value.(*lruSessionCacheEntry).state, true
-	}
-	return nil, false
-}
-
-var emptyConfig Config
-
-func defaultConfig() *Config {
-	return &emptyConfig
-}
-
-func unexpectedMessageError(wanted, got any) error {
-	return fmt.Errorf("tls: received unexpected handshake message of type %T when waiting for %T", got, wanted)
-}
-
-func isSupportedSignatureAlgorithm(sigAlg SignatureScheme, supportedSignatureAlgorithms []SignatureScheme) bool {
-	for _, s := range supportedSignatureAlgorithms {
-		if s == sigAlg {
-			return true
-		}
-	}
-	return false
-}
diff --git a/contrib/go/_std_1.18/src/crypto/tls/conn.go b/contrib/go/_std_1.18/src/crypto/tls/conn.go
deleted file mode 100644
index 0dae8e34a1..0000000000
--- a/contrib/go/_std_1.18/src/crypto/tls/conn.go
+++ /dev/null
@@ -1,1543 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// TLS low level connection and record layer
-
-package tls
-
-import (
-	"bytes"
-	"context"
-	"crypto/cipher"
-	"crypto/subtle"
-	"crypto/x509"
-	"errors"
-	"fmt"
-	"hash"
-	"io"
-	"net"
-	"sync"
-	"sync/atomic"
-	"time"
-)
-
-// A Conn represents a secured connection.
-// It implements the net.Conn interface.
-type Conn struct {
-	// constant
-	conn        net.Conn
-	isClient    bool
-	handshakeFn func(context.Context) error // (*Conn).clientHandshake or serverHandshake
-
-	// handshakeStatus is 1 if the connection is currently transferring
-	// application data (i.e. is not currently processing a handshake).
-	// handshakeStatus == 1 implies handshakeErr == nil.
-	// This field is only to be accessed with sync/atomic.
-	handshakeStatus uint32
-	// constant after handshake; protected by handshakeMutex
-	handshakeMutex sync.Mutex
-	handshakeErr   error   // error resulting from handshake
-	vers           uint16  // TLS version
-	haveVers       bool    // version has been negotiated
-	config         *Config // configuration passed to constructor
-	// handshakes counts the number of handshakes performed on the
-	// connection so far. If renegotiation is disabled then this is either
-	// zero or one.
-	handshakes       int
-	didResume        bool // whether this connection was a session resumption
-	cipherSuite      uint16
-	ocspResponse     []byte   // stapled OCSP response
-	scts             [][]byte // signed certificate timestamps from server
-	peerCertificates []*x509.Certificate
-	// verifiedChains contains the certificate chains that we built, as
-	// opposed to the ones presented by the server.
-	verifiedChains [][]*x509.Certificate
-	// serverName contains the server name indicated by the client, if any.
-	serverName string
-	// secureRenegotiation is true if the server echoed the secure
-	// renegotiation extension. (This is meaningless as a server because
-	// renegotiation is not supported in that case.)
-	secureRenegotiation bool
-	// ekm is a closure for exporting keying material.
-	ekm func(label string, context []byte, length int) ([]byte, error)
-	// resumptionSecret is the resumption_master_secret for handling
-	// NewSessionTicket messages. nil if config.SessionTicketsDisabled.
-	resumptionSecret []byte
-
-	// ticketKeys is the set of active session ticket keys for this
-	// connection. The first one is used to encrypt new tickets and
-	// all are tried to decrypt tickets.
-	ticketKeys []ticketKey
-
-	// clientFinishedIsFirst is true if the client sent the first Finished
-	// message during the most recent handshake. This is recorded because
-	// the first transmitted Finished message is the tls-unique
-	// channel-binding value.
-	clientFinishedIsFirst bool
-
-	// closeNotifyErr is any error from sending the alertCloseNotify record.
-	closeNotifyErr error
-	// closeNotifySent is true if the Conn attempted to send an
-	// alertCloseNotify record.
-	closeNotifySent bool
-
-	// clientFinished and serverFinished contain the Finished message sent
-	// by the client or server in the most recent handshake. This is
-	// retained to support the renegotiation extension and tls-unique
-	// channel-binding.
-	clientFinished [12]byte
-	serverFinished [12]byte
-
-	// clientProtocol is the negotiated ALPN protocol.
-	clientProtocol string
-
-	// input/output
-	in, out   halfConn
-	rawInput  bytes.Buffer // raw input, starting with a record header
-	input     bytes.Reader // application data waiting to be read, from rawInput.Next
-	hand      bytes.Buffer // handshake data waiting to be read
-	buffering bool         // whether records are buffered in sendBuf
-	sendBuf   []byte       // a buffer of records waiting to be sent
-
-	// bytesSent counts the bytes of application data sent.
-	// packetsSent counts packets.
-	bytesSent   int64
-	packetsSent int64
-
-	// retryCount counts the number of consecutive non-advancing records
-	// received by Conn.readRecord. That is, records that neither advance the
-	// handshake, nor deliver application data. Protected by in.Mutex.
-	retryCount int
-
-	// activeCall is an atomic int32; the low bit is whether Close has
-	// been called. the rest of the bits are the number of goroutines
-	// in Conn.Write.
-	activeCall int32
-
-	tmp [16]byte
-}
-
-// Access to net.Conn methods.
-// Cannot just embed net.Conn because that would
-// export the struct field too.
-
-// LocalAddr returns the local network address.
-func (c *Conn) LocalAddr() net.Addr {
-	return c.conn.LocalAddr()
-}
-
-// RemoteAddr returns the remote network address.
-func (c *Conn) RemoteAddr() net.Addr {
-	return c.conn.RemoteAddr()
-}
-
-// SetDeadline sets the read and write deadlines associated with the connection.
-// A zero value for t means Read and Write will not time out.
-// After a Write has timed out, the TLS state is corrupt and all future writes will return the same error.
-func (c *Conn) SetDeadline(t time.Time) error {
-	return c.conn.SetDeadline(t)
-}
-
-// SetReadDeadline sets the read deadline on the underlying connection.
-// A zero value for t means Read will not time out.
-func (c *Conn) SetReadDeadline(t time.Time) error {
-	return c.conn.SetReadDeadline(t)
-}
-
-// SetWriteDeadline sets the write deadline on the underlying connection.
-// A zero value for t means Write will not time out.
-// After a Write has timed out, the TLS state is corrupt and all future writes will return the same error.
-func (c *Conn) SetWriteDeadline(t time.Time) error {
-	return c.conn.SetWriteDeadline(t)
-}
-
-// NetConn returns the underlying connection that is wrapped by c.
-// Note that writing to or reading from this connection directly will corrupt the
-// TLS session.
-func (c *Conn) NetConn() net.Conn {
-	return c.conn
-}
-
-// A halfConn represents one direction of the record layer
-// connection, either sending or receiving.
-type halfConn struct {
-	sync.Mutex
-
-	err     error  // first permanent error
-	version uint16 // protocol version
-	cipher  any    // cipher algorithm
-	mac     hash.Hash
-	seq     [8]byte // 64-bit sequence number
-
-	scratchBuf [13]byte // to avoid allocs; interface method args escape
-
-	nextCipher any       // next encryption state
-	nextMac    hash.Hash // next MAC algorithm
-
-	trafficSecret []byte // current TLS 1.3 traffic secret
-}
-
-type permanentError struct {
-	err net.Error
-}
-
-func (e *permanentError) Error() string   { return e.err.Error() }
-func (e *permanentError) Unwrap() error   { return e.err }
-func (e *permanentError) Timeout() bool   { return e.err.Timeout() }
-func (e *permanentError) Temporary() bool { return false }
-
-func (hc *halfConn) setErrorLocked(err error) error {
-	if e, ok := err.(net.Error); ok {
-		hc.err = &permanentError{err: e}
-	} else {
-		hc.err = err
-	}
-	return hc.err
-}
-
-// prepareCipherSpec sets the encryption and MAC states
-// that a subsequent changeCipherSpec will use.
-func (hc *halfConn) prepareCipherSpec(version uint16, cipher any, mac hash.Hash) {
-	hc.version = version
-	hc.nextCipher = cipher
-	hc.nextMac = mac
-}
-
-// changeCipherSpec changes the encryption and MAC states
-// to the ones previously passed to prepareCipherSpec.
-func (hc *halfConn) changeCipherSpec() error {
-	if hc.nextCipher == nil || hc.version == VersionTLS13 {
-		return alertInternalError
-	}
-	hc.cipher = hc.nextCipher
-	hc.mac = hc.nextMac
-	hc.nextCipher = nil
-	hc.nextMac = nil
-	for i := range hc.seq {
-		hc.seq[i] = 0
-	}
-	return nil
-}
-
-func (hc *halfConn) setTrafficSecret(suite *cipherSuiteTLS13, secret []byte) {
-	hc.trafficSecret = secret
-	key, iv := suite.trafficKey(secret)
-	hc.cipher = suite.aead(key, iv)
-	for i := range hc.seq {
-		hc.seq[i] = 0
-	}
-}
-
-// incSeq increments the sequence number.
-func (hc *halfConn) incSeq() {
-	for i := 7; i >= 0; i-- {
-		hc.seq[i]++
-		if hc.seq[i] != 0 {
-			return
-		}
-	}
-
-	// Not allowed to let sequence number wrap.
-	// Instead, must renegotiate before it does.
-	// Not likely enough to bother.
-	panic("TLS: sequence number wraparound")
-}
-
-// explicitNonceLen returns the number of bytes of explicit nonce or IV included
-// in each record. Explicit nonces are present only in CBC modes after TLS 1.0
-// and in certain AEAD modes in TLS 1.2.
-func (hc *halfConn) explicitNonceLen() int {
-	if hc.cipher == nil {
-		return 0
-	}
-
-	switch c := hc.cipher.(type) {
-	case cipher.Stream:
-		return 0
-	case aead:
-		return c.explicitNonceLen()
-	case cbcMode:
-		// TLS 1.1 introduced a per-record explicit IV to fix the BEAST attack.
-		if hc.version >= VersionTLS11 {
-			return c.BlockSize()
-		}
-		return 0
-	default:
-		panic("unknown cipher type")
-	}
-}
-
-// extractPadding returns, in constant time, the length of the padding to remove
-// from the end of payload. It also returns a byte which is equal to 255 if the
-// padding was valid and 0 otherwise. See RFC 2246, Section 6.2.3.2.
-func extractPadding(payload []byte) (toRemove int, good byte) {
-	if len(payload) < 1 {
-		return 0, 0
-	}
-
-	paddingLen := payload[len(payload)-1]
-	t := uint(len(payload)-1) - uint(paddingLen)
-	// if len(payload) >= (paddingLen - 1) then the MSB of t is zero
-	good = byte(int32(^t) >> 31)
-
-	// The maximum possible padding length plus the actual length field
-	toCheck := 256
-	// The length of the padded data is public, so we can use an if here
-	if toCheck > len(payload) {
-		toCheck = len(payload)
-	}
-
-	for i := 0; i < toCheck; i++ {
-		t := uint(paddingLen) - uint(i)
-		// if i <= paddingLen then the MSB of t is zero
-		mask := byte(int32(^t) >> 31)
-		b := payload[len(payload)-1-i]
-		good &^= mask&paddingLen ^ mask&b
-	}
-
-	// We AND together the bits of good and replicate the result across
-	// all the bits.
-	good &= good << 4
-	good &= good << 2
-	good &= good << 1
-	good = uint8(int8(good) >> 7)
-
-	// Zero the padding length on error. This ensures any unchecked bytes
-	// are included in the MAC. Otherwise, an attacker that could
-	// distinguish MAC failures from padding failures could mount an attack
-	// similar to POODLE in SSL 3.0: given a good ciphertext that uses a
-	// full block's worth of padding, replace the final block with another
-	// block. If the MAC check passed but the padding check failed, the
-	// last byte of that block decrypted to the block size.
-	//
-	// See also macAndPaddingGood logic below.
-	paddingLen &= good
-
-	toRemove = int(paddingLen) + 1
-	return
-}
-
-func roundUp(a, b int) int {
-	return a + (b-a%b)%b
-}
-
-// cbcMode is an interface for block ciphers using cipher block chaining.
-type cbcMode interface {
-	cipher.BlockMode
-	SetIV([]byte)
-}
-
-// decrypt authenticates and decrypts the record if protection is active at
-// this stage. The returned plaintext might overlap with the input.
-func (hc *halfConn) decrypt(record []byte) ([]byte, recordType, error) {
-	var plaintext []byte
-	typ := recordType(record[0])
-	payload := record[recordHeaderLen:]
-
-	// In TLS 1.3, change_cipher_spec messages are to be ignored without being
-	// decrypted. See RFC 8446, Appendix D.4.
-	if hc.version == VersionTLS13 && typ == recordTypeChangeCipherSpec {
-		return payload, typ, nil
-	}
-
-	paddingGood := byte(255)
-	paddingLen := 0
-
-	explicitNonceLen := hc.explicitNonceLen()
-
-	if hc.cipher != nil {
-		switch c := hc.cipher.(type) {
-		case cipher.Stream:
-			c.XORKeyStream(payload, payload)
-		case aead:
-			if len(payload) < explicitNonceLen {
-				return nil, 0, alertBadRecordMAC
-			}
-			nonce := payload[:explicitNonceLen]
-			if len(nonce) == 0 {
-				nonce = hc.seq[:]
-			}
-			payload = payload[explicitNonceLen:]
-
-			var additionalData []byte
-			if hc.version == VersionTLS13 {
-				additionalData = record[:recordHeaderLen]
-			} else {
-				additionalData = append(hc.scratchBuf[:0], hc.seq[:]...)
-				additionalData = append(additionalData, record[:3]...)
-				n := len(payload) - c.Overhead()
-				additionalData = append(additionalData, byte(n>>8), byte(n))
-			}
-
-			var err error
-			plaintext, err = c.Open(payload[:0], nonce, payload, additionalData)
-			if err != nil {
-				return nil, 0, alertBadRecordMAC
-			}
-		case cbcMode:
-			blockSize := c.BlockSize()
-			minPayload := explicitNonceLen + roundUp(hc.mac.Size()+1, blockSize)
-			if len(payload)%blockSize != 0 || len(payload) < minPayload {
-				return nil, 0, alertBadRecordMAC
-			}
-
-			if explicitNonceLen > 0 {
-				c.SetIV(payload[:explicitNonceLen])
-				payload = payload[explicitNonceLen:]
-			}
-			c.CryptBlocks(payload, payload)
-
-			// In a limited attempt to protect against CBC padding oracles like
-			// Lucky13, the data past paddingLen (which is secret) is passed to
-			// the MAC function as extra data, to be fed into the HMAC after
-			// computing the digest. This makes the MAC roughly constant time as
-			// long as the digest computation is constant time and does not
-			// affect the subsequent write, modulo cache effects.
-			paddingLen, paddingGood = extractPadding(payload)
-		default:
-			panic("unknown cipher type")
-		}
-
-		if hc.version == VersionTLS13 {
-			if typ != recordTypeApplicationData {
-				return nil, 0, alertUnexpectedMessage
-			}
-			if len(plaintext) > maxPlaintext+1 {
-				return nil, 0, alertRecordOverflow
-			}
-			// Remove padding and find the ContentType scanning from the end.
-			for i := len(plaintext) - 1; i >= 0; i-- {
-				if plaintext[i] != 0 {
-					typ = recordType(plaintext[i])
-					plaintext = plaintext[:i]
-					break
-				}
-				if i == 0 {
-					return nil, 0, alertUnexpectedMessage
-				}
-			}
-		}
-	} else {
-		plaintext = payload
-	}
-
-	if hc.mac != nil {
-		macSize := hc.mac.Size()
-		if len(payload) < macSize {
-			return nil, 0, alertBadRecordMAC
-		}
-
-		n := len(payload) - macSize - paddingLen
-		n = subtle.ConstantTimeSelect(int(uint32(n)>>31), 0, n) // if n < 0 { n = 0 }
-		record[3] = byte(n >> 8)
-		record[4] = byte(n)
-		remoteMAC := payload[n : n+macSize]
-		localMAC := tls10MAC(hc.mac, hc.scratchBuf[:0], hc.seq[:], record[:recordHeaderLen], payload[:n], payload[n+macSize:])
-
-		// This is equivalent to checking the MACs and paddingGood
-		// separately, but in constant-time to prevent distinguishing
-		// padding failures from MAC failures. Depending on what value
-		// of paddingLen was returned on bad padding, distinguishing
-		// bad MAC from bad padding can lead to an attack.
-		//
-		// See also the logic at the end of extractPadding.
-		macAndPaddingGood := subtle.ConstantTimeCompare(localMAC, remoteMAC) & int(paddingGood)
-		if macAndPaddingGood != 1 {
-			return nil, 0, alertBadRecordMAC
-		}
-
-		plaintext = payload[:n]
-	}
-
-	hc.incSeq()
-	return plaintext, typ, nil
-}
-
-// sliceForAppend extends the input slice by n bytes. head is the full extended
-// slice, while tail is the appended part. If the original slice has sufficient
-// capacity no allocation is performed.
-func sliceForAppend(in []byte, n int) (head, tail []byte) {
-	if total := len(in) + n; cap(in) >= total {
-		head = in[:total]
-	} else {
-		head = make([]byte, total)
-		copy(head, in)
-	}
-	tail = head[len(in):]
-	return
-}
-
-// encrypt encrypts payload, adding the appropriate nonce and/or MAC, and
-// appends it to record, which must already contain the record header.
-func (hc *halfConn) encrypt(record, payload []byte, rand io.Reader) ([]byte, error) {
-	if hc.cipher == nil {
-		return append(record, payload...), nil
-	}
-
-	var explicitNonce []byte
-	if explicitNonceLen := hc.explicitNonceLen(); explicitNonceLen > 0 {
-		record, explicitNonce = sliceForAppend(record, explicitNonceLen)
-		if _, isCBC := hc.cipher.(cbcMode); !isCBC && explicitNonceLen < 16 {
-			// The AES-GCM construction in TLS has an explicit nonce so that the
-			// nonce can be random. However, the nonce is only 8 bytes which is
-			// too small for a secure, random nonce. Therefore we use the
-			// sequence number as the nonce. The 3DES-CBC construction also has
-			// an 8 bytes nonce but its nonces must be unpredictable (see RFC
-			// 5246, Appendix F.3), forcing us to use randomness. That's not
-			// 3DES' biggest problem anyway because the birthday bound on block
-			// collision is reached first due to its similarly small block size
-			// (see the Sweet32 attack).
-			copy(explicitNonce, hc.seq[:])
-		} else {
-			if _, err := io.ReadFull(rand, explicitNonce); err != nil {
-				return nil, err
-			}
-		}
-	}
-
-	var dst []byte
-	switch c := hc.cipher.(type) {
-	case cipher.Stream:
-		mac := tls10MAC(hc.mac, hc.scratchBuf[:0], hc.seq[:], record[:recordHeaderLen], payload, nil)
-		record, dst = sliceForAppend(record, len(payload)+len(mac))
-		c.XORKeyStream(dst[:len(payload)], payload)
-		c.XORKeyStream(dst[len(payload):], mac)
-	case aead:
-		nonce := explicitNonce
-		if len(nonce) == 0 {
-			nonce = hc.seq[:]
-		}
-
-		if hc.version == VersionTLS13 {
-			record = append(record, payload...)
-
-			// Encrypt the actual ContentType and replace the plaintext one.
-			record = append(record, record[0])
-			record[0] = byte(recordTypeApplicationData)
-
-			n := len(payload) + 1 + c.Overhead()
-			record[3] = byte(n >> 8)
-			record[4] = byte(n)
-
-			record = c.Seal(record[:recordHeaderLen],
-				nonce, record[recordHeaderLen:], record[:recordHeaderLen])
-		} else {
-			additionalData := append(hc.scratchBuf[:0], hc.seq[:]...)
-			additionalData = append(additionalData, record[:recordHeaderLen]...)
-			record = c.Seal(record, nonce, payload, additionalData)
-		}
-	case cbcMode:
-		mac := tls10MAC(hc.mac, hc.scratchBuf[:0], hc.seq[:], record[:recordHeaderLen], payload, nil)
-		blockSize := c.BlockSize()
-		plaintextLen := len(payload) + len(mac)
-		paddingLen := blockSize - plaintextLen%blockSize
-		record, dst = sliceForAppend(record, plaintextLen+paddingLen)
-		copy(dst, payload)
-		copy(dst[len(payload):], mac)
-		for i := plaintextLen; i < len(dst); i++ {
-			dst[i] = byte(paddingLen - 1)
-		}
-		if len(explicitNonce) > 0 {
-			c.SetIV(explicitNonce)
-		}
-		c.CryptBlocks(dst, dst)
-	default:
-		panic("unknown cipher type")
-	}
-
-	// Update length to include nonce, MAC and any block padding needed.
-	n := len(record) - recordHeaderLen
-	record[3] = byte(n >> 8)
-	record[4] = byte(n)
-	hc.incSeq()
-
-	return record, nil
-}
-
-// RecordHeaderError is returned when a TLS record header is invalid.
-type RecordHeaderError struct {
-	// Msg contains a human readable string that describes the error.
-	Msg string
-	// RecordHeader contains the five bytes of TLS record header that
-	// triggered the error.
-	RecordHeader [5]byte
-	// Conn provides the underlying net.Conn in the case that a client
-	// sent an initial handshake that didn't look like TLS.
-	// It is nil if there's already been a handshake or a TLS alert has
-	// been written to the connection.
-	Conn net.Conn
-}
-
-func (e RecordHeaderError) Error() string { return "tls: " + e.Msg }
-
-func (c *Conn) newRecordHeaderError(conn net.Conn, msg string) (err RecordHeaderError) {
-	err.Msg = msg
-	err.Conn = conn
-	copy(err.RecordHeader[:], c.rawInput.Bytes())
-	return err
-}
-
-func (c *Conn) readRecord() error {
-	return c.readRecordOrCCS(false)
-}
-
-func (c *Conn) readChangeCipherSpec() error {
-	return c.readRecordOrCCS(true)
-}
-
-// readRecordOrCCS reads one or more TLS records from the connection and
-// updates the record layer state. Some invariants:
-//   * c.in must be locked
-//   * c.input must be empty
-// During the handshake one and only one of the following will happen:
-//   - c.hand grows
-//   - c.in.changeCipherSpec is called
-//   - an error is returned
-// After the handshake one and only one of the following will happen:
-//   - c.hand grows
-//   - c.input is set
-//   - an error is returned
-func (c *Conn) readRecordOrCCS(expectChangeCipherSpec bool) error {
-	if c.in.err != nil {
-		return c.in.err
-	}
-	handshakeComplete := c.handshakeComplete()
-
-	// This function modifies c.rawInput, which owns the c.input memory.
-	if c.input.Len() != 0 {
-		return c.in.setErrorLocked(errors.New("tls: internal error: attempted to read record with pending application data"))
-	}
-	c.input.Reset(nil)
-
-	// Read header, payload.
-	if err := c.readFromUntil(c.conn, recordHeaderLen); err != nil {
-		// RFC 8446, Section 6.1 suggests that EOF without an alertCloseNotify
-		// is an error, but popular web sites seem to do this, so we accept it
-		// if and only if at the record boundary.
-		if err == io.ErrUnexpectedEOF && c.rawInput.Len() == 0 {
-			err = io.EOF
-		}
-		if e, ok := err.(net.Error); !ok || !e.Temporary() {
-			c.in.setErrorLocked(err)
-		}
-		return err
-	}
-	hdr := c.rawInput.Bytes()[:recordHeaderLen]
-	typ := recordType(hdr[0])
-
-	// No valid TLS record has a type of 0x80, however SSLv2 handshakes
-	// start with a uint16 length where the MSB is set and the first record
-	// is always < 256 bytes long. Therefore typ == 0x80 strongly suggests
-	// an SSLv2 client.
-	if !handshakeComplete && typ == 0x80 {
-		c.sendAlert(alertProtocolVersion)
-		return c.in.setErrorLocked(c.newRecordHeaderError(nil, "unsupported SSLv2 handshake received"))
-	}
-
-	vers := uint16(hdr[1])<<8 | uint16(hdr[2])
-	n := int(hdr[3])<<8 | int(hdr[4])
-	if c.haveVers && c.vers != VersionTLS13 && vers != c.vers {
-		c.sendAlert(alertProtocolVersion)
-		msg := fmt.Sprintf("received record with version %x when expecting version %x", vers, c.vers)
-		return c.in.setErrorLocked(c.newRecordHeaderError(nil, msg))
-	}
-	if !c.haveVers {
-		// First message, be extra suspicious: this might not be a TLS
-		// client. Bail out before reading a full 'body', if possible.
-		// The current max version is 3.3 so if the version is >= 16.0,
-		// it's probably not real.
-		if (typ != recordTypeAlert && typ != recordTypeHandshake) || vers >= 0x1000 {
-			return c.in.setErrorLocked(c.newRecordHeaderError(c.conn, "first record does not look like a TLS handshake"))
-		}
-	}
-	if c.vers == VersionTLS13 && n > maxCiphertextTLS13 || n > maxCiphertext {
-		c.sendAlert(alertRecordOverflow)
-		msg := fmt.Sprintf("oversized record received with length %d", n)
-		return c.in.setErrorLocked(c.newRecordHeaderError(nil, msg))
-	}
-	if err := c.readFromUntil(c.conn, recordHeaderLen+n); err != nil {
-		if e, ok := err.(net.Error); !ok || !e.Temporary() {
-			c.in.setErrorLocked(err)
-		}
-		return err
-	}
-
-	// Process message.
-	record := c.rawInput.Next(recordHeaderLen + n)
-	data, typ, err := c.in.decrypt(record)
-	if err != nil {
-		return c.in.setErrorLocked(c.sendAlert(err.(alert)))
-	}
-	if len(data) > maxPlaintext {
-		return c.in.setErrorLocked(c.sendAlert(alertRecordOverflow))
-	}
-
-	// Application Data messages are always protected.
-	if c.in.cipher == nil && typ == recordTypeApplicationData {
-		return c.in.setErrorLocked(c.sendAlert(alertUnexpectedMessage))
-	}
-
-	if typ != recordTypeAlert && typ != recordTypeChangeCipherSpec && len(data) > 0 {
-		// This is a state-advancing message: reset the retry count.
-		c.retryCount = 0
-	}
-
-	// Handshake messages MUST NOT be interleaved with other record types in TLS 1.3.
-	if c.vers == VersionTLS13 && typ != recordTypeHandshake && c.hand.Len() > 0 {
-		return c.in.setErrorLocked(c.sendAlert(alertUnexpectedMessage))
-	}
-
-	switch typ {
-	default:
-		return c.in.setErrorLocked(c.sendAlert(alertUnexpectedMessage))
-
-	case recordTypeAlert:
-		if len(data) != 2 {
-			return c.in.setErrorLocked(c.sendAlert(alertUnexpectedMessage))
-		}
-		if alert(data[1]) == alertCloseNotify {
-			return c.in.setErrorLocked(io.EOF)
-		}
-		if c.vers == VersionTLS13 {
-			return c.in.setErrorLocked(&net.OpError{Op: "remote error", Err: alert(data[1])})
-		}
-		switch data[0] {
-		case alertLevelWarning:
-			// Drop the record on the floor and retry.
-			return c.retryReadRecord(expectChangeCipherSpec)
-		case alertLevelError:
-			return c.in.setErrorLocked(&net.OpError{Op: "remote error", Err: alert(data[1])})
-		default:
-			return c.in.setErrorLocked(c.sendAlert(alertUnexpectedMessage))
-		}
-
-	case recordTypeChangeCipherSpec:
-		if len(data) != 1 || data[0] != 1 {
-			return c.in.setErrorLocked(c.sendAlert(alertDecodeError))
-		}
-		// Handshake messages are not allowed to fragment across the CCS.
-		if c.hand.Len() > 0 {
-			return c.in.setErrorLocked(c.sendAlert(alertUnexpectedMessage))
-		}
-		// In TLS 1.3, change_cipher_spec records are ignored until the
-		// Finished. See RFC 8446, Appendix D.4. Note that according to Section
-		// 5, a server can send a ChangeCipherSpec before its ServerHello, when
-		// c.vers is still unset. That's not useful though and suspicious if the
-		// server then selects a lower protocol version, so don't allow that.
-		if c.vers == VersionTLS13 {
-			return c.retryReadRecord(expectChangeCipherSpec)
-		}
-		if !expectChangeCipherSpec {
-			return c.in.setErrorLocked(c.sendAlert(alertUnexpectedMessage))
-		}
-		if err := c.in.changeCipherSpec(); err != nil {
-			return c.in.setErrorLocked(c.sendAlert(err.(alert)))
-		}
-
-	case recordTypeApplicationData:
-		if !handshakeComplete || expectChangeCipherSpec {
-			return c.in.setErrorLocked(c.sendAlert(alertUnexpectedMessage))
-		}
-		// Some OpenSSL servers send empty records in order to randomize the
-		// CBC IV. Ignore a limited number of empty records.
-		if len(data) == 0 {
-			return c.retryReadRecord(expectChangeCipherSpec)
-		}
-		// Note that data is owned by c.rawInput, following the Next call above,
-		// to avoid copying the plaintext. This is safe because c.rawInput is
-		// not read from or written to until c.input is drained.
-		c.input.Reset(data)
-
-	case recordTypeHandshake:
-		if len(data) == 0 || expectChangeCipherSpec {
-			return c.in.setErrorLocked(c.sendAlert(alertUnexpectedMessage))
-		}
-		c.hand.Write(data)
-	}
-
-	return nil
-}
-
-// retryReadRecord recurses into readRecordOrCCS to drop a non-advancing record, like
-// a warning alert, empty application_data, or a change_cipher_spec in TLS 1.3.
-func (c *Conn) retryReadRecord(expectChangeCipherSpec bool) error {
-	c.retryCount++
-	if c.retryCount > maxUselessRecords {
-		c.sendAlert(alertUnexpectedMessage)
-		return c.in.setErrorLocked(errors.New("tls: too many ignored records"))
-	}
-	return c.readRecordOrCCS(expectChangeCipherSpec)
-}
-
-// atLeastReader reads from R, stopping with EOF once at least N bytes have been
-// read. It is different from an io.LimitedReader in that it doesn't cut short
-// the last Read call, and in that it considers an early EOF an error.
-type atLeastReader struct {
-	R io.Reader
-	N int64
-}
-
-func (r *atLeastReader) Read(p []byte) (int, error) {
-	if r.N <= 0 {
-		return 0, io.EOF
-	}
-	n, err := r.R.Read(p)
-	r.N -= int64(n) // won't underflow unless len(p) >= n > 9223372036854775809
-	if r.N > 0 && err == io.EOF {
-		return n, io.ErrUnexpectedEOF
-	}
-	if r.N <= 0 && err == nil {
-		return n, io.EOF
-	}
-	return n, err
-}
-
-// readFromUntil reads from r into c.rawInput until c.rawInput contains
-// at least n bytes or else returns an error.
-func (c *Conn) readFromUntil(r io.Reader, n int) error {
-	if c.rawInput.Len() >= n {
-		return nil
-	}
-	needs := n - c.rawInput.Len()
-	// There might be extra input waiting on the wire. Make a best effort
-	// attempt to fetch it so that it can be used in (*Conn).Read to
-	// "predict" closeNotify alerts.
-	c.rawInput.Grow(needs + bytes.MinRead)
-	_, err := c.rawInput.ReadFrom(&atLeastReader{r, int64(needs)})
-	return err
-}
-
-// sendAlert sends a TLS alert message.
-func (c *Conn) sendAlertLocked(err alert) error {
-	switch err {
-	case alertNoRenegotiation, alertCloseNotify:
-		c.tmp[0] = alertLevelWarning
-	default:
-		c.tmp[0] = alertLevelError
-	}
-	c.tmp[1] = byte(err)
-
-	_, writeErr := c.writeRecordLocked(recordTypeAlert, c.tmp[0:2])
-	if err == alertCloseNotify {
-		// closeNotify is a special case in that it isn't an error.
-		return writeErr
-	}
-
-	return c.out.setErrorLocked(&net.OpError{Op: "local error", Err: err})
-}
-
-// sendAlert sends a TLS alert message.
-func (c *Conn) sendAlert(err alert) error {
-	c.out.Lock()
-	defer c.out.Unlock()
-	return c.sendAlertLocked(err)
-}
-
-const (
-	// tcpMSSEstimate is a conservative estimate of the TCP maximum segment
-	// size (MSS). A constant is used, rather than querying the kernel for
-	// the actual MSS, to avoid complexity. The value here is the IPv6
-	// minimum MTU (1280 bytes) minus the overhead of an IPv6 header (40
-	// bytes) and a TCP header with timestamps (32 bytes).
-	tcpMSSEstimate = 1208
-
-	// recordSizeBoostThreshold is the number of bytes of application data
-	// sent after which the TLS record size will be increased to the
-	// maximum.
-	recordSizeBoostThreshold = 128 * 1024
-)
-
-// maxPayloadSizeForWrite returns the maximum TLS payload size to use for the
-// next application data record. There is the following trade-off:
-//
-//   - For latency-sensitive applications, such as web browsing, each TLS
-//     record should fit in one TCP segment.
-//   - For throughput-sensitive applications, such as large file transfers,
-//     larger TLS records better amortize framing and encryption overheads.
-//
-// A simple heuristic that works well in practice is to use small records for
-// the first 1MB of data, then use larger records for subsequent data, and
-// reset back to smaller records after the connection becomes idle. See "High
-// Performance Web Networking", Chapter 4, or:
-// https://www.igvita.com/2013/10/24/optimizing-tls-record-size-and-buffering-latency/
-//
-// In the interests of simplicity and determinism, this code does not attempt
-// to reset the record size once the connection is idle, however.
-func (c *Conn) maxPayloadSizeForWrite(typ recordType) int {
-	if c.config.DynamicRecordSizingDisabled || typ != recordTypeApplicationData {
-		return maxPlaintext
-	}
-
-	if c.bytesSent >= recordSizeBoostThreshold {
-		return maxPlaintext
-	}
-
-	// Subtract TLS overheads to get the maximum payload size.
-	payloadBytes := tcpMSSEstimate - recordHeaderLen - c.out.explicitNonceLen()
-	if c.out.cipher != nil {
-		switch ciph := c.out.cipher.(type) {
-		case cipher.Stream:
-			payloadBytes -= c.out.mac.Size()
-		case cipher.AEAD:
-			payloadBytes -= ciph.Overhead()
-		case cbcMode:
-			blockSize := ciph.BlockSize()
-			// The payload must fit in a multiple of blockSize, with
-			// room for at least one padding byte.
-			payloadBytes = (payloadBytes & ^(blockSize - 1)) - 1
-			// The MAC is appended before padding so affects the
-			// payload size directly.
-			payloadBytes -= c.out.mac.Size()
-		default:
-			panic("unknown cipher type")
-		}
-	}
-	if c.vers == VersionTLS13 {
-		payloadBytes-- // encrypted ContentType
-	}
-
-	// Allow packet growth in arithmetic progression up to max.
-	pkt := c.packetsSent
-	c.packetsSent++
-	if pkt > 1000 {
-		return maxPlaintext // avoid overflow in multiply below
-	}
-
-	n := payloadBytes * int(pkt+1)
-	if n > maxPlaintext {
-		n = maxPlaintext
-	}
-	return n
-}
-
-func (c *Conn) write(data []byte) (int, error) {
-	if c.buffering {
-		c.sendBuf = append(c.sendBuf, data...)
-		return len(data), nil
-	}
-
-	n, err := c.conn.Write(data)
-	c.bytesSent += int64(n)
-	return n, err
-}
-
-func (c *Conn) flush() (int, error) {
-	if len(c.sendBuf) == 0 {
-		return 0, nil
-	}
-
-	n, err := c.conn.Write(c.sendBuf)
-	c.bytesSent += int64(n)
-	c.sendBuf = nil
-	c.buffering = false
-	return n, err
-}
-
-// outBufPool pools the record-sized scratch buffers used by writeRecordLocked.
-var outBufPool = sync.Pool{
-	New: func() any {
-		return new([]byte)
-	},
-}
-
-// writeRecordLocked writes a TLS record with the given type and payload to the
-// connection and updates the record layer state.
-func (c *Conn) writeRecordLocked(typ recordType, data []byte) (int, error) {
-	outBufPtr := outBufPool.Get().(*[]byte)
-	outBuf := *outBufPtr
-	defer func() {
-		// You might be tempted to simplify this by just passing &outBuf to Put,
-		// but that would make the local copy of the outBuf slice header escape
-		// to the heap, causing an allocation. Instead, we keep around the
-		// pointer to the slice header returned by Get, which is already on the
-		// heap, and overwrite and return that.
-		*outBufPtr = outBuf
-		outBufPool.Put(outBufPtr)
-	}()
-
-	var n int
-	for len(data) > 0 {
-		m := len(data)
-		if maxPayload := c.maxPayloadSizeForWrite(typ); m > maxPayload {
-			m = maxPayload
-		}
-
-		_, outBuf = sliceForAppend(outBuf[:0], recordHeaderLen)
-		outBuf[0] = byte(typ)
-		vers := c.vers
-		if vers == 0 {
-			// Some TLS servers fail if the record version is
-			// greater than TLS 1.0 for the initial ClientHello.
-			vers = VersionTLS10
-		} else if vers == VersionTLS13 {
-			// TLS 1.3 froze the record layer version to 1.2.
-			// See RFC 8446, Section 5.1.
-			vers = VersionTLS12
-		}
-		outBuf[1] = byte(vers >> 8)
-		outBuf[2] = byte(vers)
-		outBuf[3] = byte(m >> 8)
-		outBuf[4] = byte(m)
-
-		var err error
-		outBuf, err = c.out.encrypt(outBuf, data[:m], c.config.rand())
-		if err != nil {
-			return n, err
-		}
-		if _, err := c.write(outBuf); err != nil {
-			return n, err
-		}
-		n += m
-		data = data[m:]
-	}
-
-	if typ == recordTypeChangeCipherSpec && c.vers != VersionTLS13 {
-		if err := c.out.changeCipherSpec(); err != nil {
-			return n, c.sendAlertLocked(err.(alert))
-		}
-	}
-
-	return n, nil
-}
-
-// writeRecord writes a TLS record with the given type and payload to the
-// connection and updates the record layer state.
-func (c *Conn) writeRecord(typ recordType, data []byte) (int, error) {
-	c.out.Lock()
-	defer c.out.Unlock()
-
-	return c.writeRecordLocked(typ, data)
-}
-
-// readHandshake reads the next handshake message from
-// the record layer.
-func (c *Conn) readHandshake() (any, error) {
-	for c.hand.Len() < 4 {
-		if err := c.readRecord(); err != nil {
-			return nil, err
-		}
-	}
-
-	data := c.hand.Bytes()
-	n := int(data[1])<<16 | int(data[2])<<8 | int(data[3])
-	if n > maxHandshake {
-		c.sendAlertLocked(alertInternalError)
-		return nil, c.in.setErrorLocked(fmt.Errorf("tls: handshake message of length %d bytes exceeds maximum of %d bytes", n, maxHandshake))
-	}
-	for c.hand.Len() < 4+n {
-		if err := c.readRecord(); err != nil {
-			return nil, err
-		}
-	}
-	data = c.hand.Next(4 + n)
-	var m handshakeMessage
-	switch data[0] {
-	case typeHelloRequest:
-		m = new(helloRequestMsg)
-	case typeClientHello:
-		m = new(clientHelloMsg)
-	case typeServerHello:
-		m = new(serverHelloMsg)
-	case typeNewSessionTicket:
-		if c.vers == VersionTLS13 {
-			m = new(newSessionTicketMsgTLS13)
-		} else {
-			m = new(newSessionTicketMsg)
-		}
-	case typeCertificate:
-		if c.vers == VersionTLS13 {
-			m = new(certificateMsgTLS13)
-		} else {
-			m = new(certificateMsg)
-		}
-	case typeCertificateRequest:
-		if c.vers == VersionTLS13 {
-			m = new(certificateRequestMsgTLS13)
-		} else {
-			m = &certificateRequestMsg{
-				hasSignatureAlgorithm: c.vers >= VersionTLS12,
-			}
-		}
-	case typeCertificateStatus:
-		m = new(certificateStatusMsg)
-	case typeServerKeyExchange:
-		m = new(serverKeyExchangeMsg)
-	case typeServerHelloDone:
-		m = new(serverHelloDoneMsg)
-	case typeClientKeyExchange:
-		m = new(clientKeyExchangeMsg)
-	case typeCertificateVerify:
-		m = &certificateVerifyMsg{
-			hasSignatureAlgorithm: c.vers >= VersionTLS12,
-		}
-	case typeFinished:
-		m = new(finishedMsg)
-	case typeEncryptedExtensions:
-		m = new(encryptedExtensionsMsg)
-	case typeEndOfEarlyData:
-		m = new(endOfEarlyDataMsg)
-	case typeKeyUpdate:
-		m = new(keyUpdateMsg)
-	default:
-		return nil, c.in.setErrorLocked(c.sendAlert(alertUnexpectedMessage))
-	}
-
-	// The handshake message unmarshalers
-	// expect to be able to keep references to data,
-	// so pass in a fresh copy that won't be overwritten.
-	data = append([]byte(nil), data...)
-
-	if !m.unmarshal(data) {
-		return nil, c.in.setErrorLocked(c.sendAlert(alertUnexpectedMessage))
-	}
-	return m, nil
-}
-
-var (
-	errShutdown = errors.New("tls: protocol is shutdown")
-)
-
-// Write writes data to the connection.
-//
-// As Write calls Handshake, in order to prevent indefinite blocking a deadline
-// must be set for both Read and Write before Write is called when the handshake
-// has not yet completed. See SetDeadline, SetReadDeadline, and
-// SetWriteDeadline.
-func (c *Conn) Write(b []byte) (int, error) {
-	// interlock with Close below
-	for {
-		x := atomic.LoadInt32(&c.activeCall)
-		if x&1 != 0 {
-			return 0, net.ErrClosed
-		}
-		if atomic.CompareAndSwapInt32(&c.activeCall, x, x+2) {
-			break
-		}
-	}
-	defer atomic.AddInt32(&c.activeCall, -2)
-
-	if err := c.Handshake(); err != nil {
-		return 0, err
-	}
-
-	c.out.Lock()
-	defer c.out.Unlock()
-
-	if err := c.out.err; err != nil {
-		return 0, err
-	}
-
-	if !c.handshakeComplete() {
-		return 0, alertInternalError
-	}
-
-	if c.closeNotifySent {
-		return 0, errShutdown
-	}
-
-	// TLS 1.0 is susceptible to a chosen-plaintext
-	// attack when using block mode ciphers due to predictable IVs.
-	// This can be prevented by splitting each Application Data
-	// record into two records, effectively randomizing the IV.
-	//
-	// https://www.openssl.org/~bodo/tls-cbc.txt
-	// https://bugzilla.mozilla.org/show_bug.cgi?id=665814
-	// https://www.imperialviolet.org/2012/01/15/beastfollowup.html
-
-	var m int
-	if len(b) > 1 && c.vers == VersionTLS10 {
-		if _, ok := c.out.cipher.(cipher.BlockMode); ok {
-			n, err := c.writeRecordLocked(recordTypeApplicationData, b[:1])
-			if err != nil {
-				return n, c.out.setErrorLocked(err)
-			}
-			m, b = 1, b[1:]
-		}
-	}
-
-	n, err := c.writeRecordLocked(recordTypeApplicationData, b)
-	return n + m, c.out.setErrorLocked(err)
-}
-
-// handleRenegotiation processes a HelloRequest handshake message.
-func (c *Conn) handleRenegotiation() error {
-	if c.vers == VersionTLS13 {
-		return errors.New("tls: internal error: unexpected renegotiation")
-	}
-
-	msg, err := c.readHandshake()
-	if err != nil {
-		return err
-	}
-
-	helloReq, ok := msg.(*helloRequestMsg)
-	if !ok {
-		c.sendAlert(alertUnexpectedMessage)
-		return unexpectedMessageError(helloReq, msg)
-	}
-
-	if !c.isClient {
-		return c.sendAlert(alertNoRenegotiation)
-	}
-
-	switch c.config.Renegotiation {
-	case RenegotiateNever:
-		return c.sendAlert(alertNoRenegotiation)
-	case RenegotiateOnceAsClient:
-		if c.handshakes > 1 {
-			return c.sendAlert(alertNoRenegotiation)
-		}
-	case RenegotiateFreelyAsClient:
-		// Ok.
-	default:
-		c.sendAlert(alertInternalError)
-		return errors.New("tls: unknown Renegotiation value")
-	}
-
-	c.handshakeMutex.Lock()
-	defer c.handshakeMutex.Unlock()
-
-	atomic.StoreUint32(&c.handshakeStatus, 0)
-	if c.handshakeErr = c.clientHandshake(context.Background()); c.handshakeErr == nil {
-		c.handshakes++
-	}
-	return c.handshakeErr
-}
-
-// handlePostHandshakeMessage processes a handshake message arrived after the
-// handshake is complete. Up to TLS 1.2, it indicates the start of a renegotiation.
-func (c *Conn) handlePostHandshakeMessage() error {
-	if c.vers != VersionTLS13 {
-		return c.handleRenegotiation()
-	}
-
-	msg, err := c.readHandshake()
-	if err != nil {
-		return err
-	}
-
-	c.retryCount++
-	if c.retryCount > maxUselessRecords {
-		c.sendAlert(alertUnexpectedMessage)
-		return c.in.setErrorLocked(errors.New("tls: too many non-advancing records"))
-	}
-
-	switch msg := msg.(type) {
-	case *newSessionTicketMsgTLS13:
-		return c.handleNewSessionTicket(msg)
-	case *keyUpdateMsg:
-		return c.handleKeyUpdate(msg)
-	default:
-		c.sendAlert(alertUnexpectedMessage)
-		return fmt.Errorf("tls: received unexpected handshake message of type %T", msg)
-	}
-}
-
-func (c *Conn) handleKeyUpdate(keyUpdate *keyUpdateMsg) error {
-	cipherSuite := cipherSuiteTLS13ByID(c.cipherSuite)
-	if cipherSuite == nil {
-		return c.in.setErrorLocked(c.sendAlert(alertInternalError))
-	}
-
-	newSecret := cipherSuite.nextTrafficSecret(c.in.trafficSecret)
-	c.in.setTrafficSecret(cipherSuite, newSecret)
-
-	if keyUpdate.updateRequested {
-		c.out.Lock()
-		defer c.out.Unlock()
-
-		msg := &keyUpdateMsg{}
-		_, err := c.writeRecordLocked(recordTypeHandshake, msg.marshal())
-		if err != nil {
-			// Surface the error at the next write.
-			c.out.setErrorLocked(err)
-			return nil
-		}
-
-		newSecret := cipherSuite.nextTrafficSecret(c.out.trafficSecret)
-		c.out.setTrafficSecret(cipherSuite, newSecret)
-	}
-
-	return nil
-}
-
-// Read reads data from the connection.
-//
-// As Read calls Handshake, in order to prevent indefinite blocking a deadline
-// must be set for both Read and Write before Read is called when the handshake
-// has not yet completed. See SetDeadline, SetReadDeadline, and
-// SetWriteDeadline.
-func (c *Conn) Read(b []byte) (int, error) {
-	if err := c.Handshake(); err != nil {
-		return 0, err
-	}
-	if len(b) == 0 {
-		// Put this after Handshake, in case people were calling
-		// Read(nil) for the side effect of the Handshake.
-		return 0, nil
-	}
-
-	c.in.Lock()
-	defer c.in.Unlock()
-
-	for c.input.Len() == 0 {
-		if err := c.readRecord(); err != nil {
-			return 0, err
-		}
-		for c.hand.Len() > 0 {
-			if err := c.handlePostHandshakeMessage(); err != nil {
-				return 0, err
-			}
-		}
-	}
-
-	n, _ := c.input.Read(b)
-
-	// If a close-notify alert is waiting, read it so that we can return (n,
-	// EOF) instead of (n, nil), to signal to the HTTP response reading
-	// goroutine that the connection is now closed. This eliminates a race
-	// where the HTTP response reading goroutine would otherwise not observe
-	// the EOF until its next read, by which time a client goroutine might
-	// have already tried to reuse the HTTP connection for a new request.
-	// See https://golang.org/cl/76400046 and https://golang.org/issue/3514
-	if n != 0 && c.input.Len() == 0 && c.rawInput.Len() > 0 &&
-		recordType(c.rawInput.Bytes()[0]) == recordTypeAlert {
-		if err := c.readRecord(); err != nil {
-			return n, err // will be io.EOF on closeNotify
-		}
-	}
-
-	return n, nil
-}
-
-// Close closes the connection.
-func (c *Conn) Close() error {
-	// Interlock with Conn.Write above.
-	var x int32
-	for {
-		x = atomic.LoadInt32(&c.activeCall)
-		if x&1 != 0 {
-			return net.ErrClosed
-		}
-		if atomic.CompareAndSwapInt32(&c.activeCall, x, x|1) {
-			break
-		}
-	}
-	if x != 0 {
-		// io.Writer and io.Closer should not be used concurrently.
-		// If Close is called while a Write is currently in-flight,
-		// interpret that as a sign that this Close is really just
-		// being used to break the Write and/or clean up resources and
-		// avoid sending the alertCloseNotify, which may block
-		// waiting on handshakeMutex or the c.out mutex.
-		return c.conn.Close()
-	}
-
-	var alertErr error
-	if c.handshakeComplete() {
-		if err := c.closeNotify(); err != nil {
-			alertErr = fmt.Errorf("tls: failed to send closeNotify alert (but connection was closed anyway): %w", err)
-		}
-	}
-
-	if err := c.conn.Close(); err != nil {
-		return err
-	}
-	return alertErr
-}
-
-var errEarlyCloseWrite = errors.New("tls: CloseWrite called before handshake complete")
-
-// CloseWrite shuts down the writing side of the connection. It should only be
-// called once the handshake has completed and does not call CloseWrite on the
-// underlying connection. Most callers should just use Close.
-func (c *Conn) CloseWrite() error {
-	if !c.handshakeComplete() {
-		return errEarlyCloseWrite
-	}
-
-	return c.closeNotify()
-}
-
-func (c *Conn) closeNotify() error {
-	c.out.Lock()
-	defer c.out.Unlock()
-
-	if !c.closeNotifySent {
-		// Set a Write Deadline to prevent possibly blocking forever.
-		c.SetWriteDeadline(time.Now().Add(time.Second * 5))
-		c.closeNotifyErr = c.sendAlertLocked(alertCloseNotify)
-		c.closeNotifySent = true
-		// Any subsequent writes will fail.
-		c.SetWriteDeadline(time.Now())
-	}
-	return c.closeNotifyErr
-}
-
-// Handshake runs the client or server handshake
-// protocol if it has not yet been run.
-//
-// Most uses of this package need not call Handshake explicitly: the
-// first Read or Write will call it automatically.
-//
-// For control over canceling or setting a timeout on a handshake, use
-// HandshakeContext or the Dialer's DialContext method instead.
-func (c *Conn) Handshake() error {
-	return c.HandshakeContext(context.Background())
-}
-
-// HandshakeContext runs the client or server handshake
-// protocol if it has not yet been run.
-//
-// The provided Context must be non-nil. If the context is canceled before
-// the handshake is complete, the handshake is interrupted and an error is returned.
-// Once the handshake has completed, cancellation of the context will not affect the
-// connection.
-//
-// Most uses of this package need not call HandshakeContext explicitly: the
-// first Read or Write will call it automatically.
-func (c *Conn) HandshakeContext(ctx context.Context) error {
-	// Delegate to unexported method for named return
-	// without confusing documented signature.
-	return c.handshakeContext(ctx)
-}
-
-func (c *Conn) handshakeContext(ctx context.Context) (ret error) {
-	// Fast sync/atomic-based exit if there is no handshake in flight and the
-	// last one succeeded without an error. Avoids the expensive context setup
-	// and mutex for most Read and Write calls.
-	if c.handshakeComplete() {
-		return nil
-	}
-
-	handshakeCtx, cancel := context.WithCancel(ctx)
-	// Note: defer this before starting the "interrupter" goroutine
-	// so that we can tell the difference between the input being canceled and
-	// this cancellation. In the former case, we need to close the connection.
-	defer cancel()
-
-	// Start the "interrupter" goroutine, if this context might be canceled.
-	// (The background context cannot).
-	//
-	// The interrupter goroutine waits for the input context to be done and
-	// closes the connection if this happens before the function returns.
-	if ctx.Done() != nil {
-		done := make(chan struct{})
-		interruptRes := make(chan error, 1)
-		defer func() {
-			close(done)
-			if ctxErr := <-interruptRes; ctxErr != nil {
-				// Return context error to user.
-				ret = ctxErr
-			}
-		}()
-		go func() {
-			select {
-			case <-handshakeCtx.Done():
-				// Close the connection, discarding the error
-				_ = c.conn.Close()
-				interruptRes <- handshakeCtx.Err()
-			case <-done:
-				interruptRes <- nil
-			}
-		}()
-	}
-
-	c.handshakeMutex.Lock()
-	defer c.handshakeMutex.Unlock()
-
-	if err := c.handshakeErr; err != nil {
-		return err
-	}
-	if c.handshakeComplete() {
-		return nil
-	}
-
-	c.in.Lock()
-	defer c.in.Unlock()
-
-	c.handshakeErr = c.handshakeFn(handshakeCtx)
-	if c.handshakeErr == nil {
-		c.handshakes++
-	} else {
-		// If an error occurred during the handshake try to flush the
-		// alert that might be left in the buffer.
-		c.flush()
-	}
-
-	if c.handshakeErr == nil && !c.handshakeComplete() {
-		c.handshakeErr = errors.New("tls: internal error: handshake should have had a result")
-	}
-	if c.handshakeErr != nil && c.handshakeComplete() {
-		panic("tls: internal error: handshake returned an error but is marked successful")
-	}
-
-	return c.handshakeErr
-}
-
-// ConnectionState returns basic TLS details about the connection.
-func (c *Conn) ConnectionState() ConnectionState {
-	c.handshakeMutex.Lock()
-	defer c.handshakeMutex.Unlock()
-	return c.connectionStateLocked()
-}
-
-func (c *Conn) connectionStateLocked() ConnectionState {
-	var state ConnectionState
-	state.HandshakeComplete = c.handshakeComplete()
-	state.Version = c.vers
-	state.NegotiatedProtocol = c.clientProtocol
-	state.DidResume = c.didResume
-	state.NegotiatedProtocolIsMutual = true
-	state.ServerName = c.serverName
-	state.CipherSuite = c.cipherSuite
-	state.PeerCertificates = c.peerCertificates
-	state.VerifiedChains = c.verifiedChains
-	state.SignedCertificateTimestamps = c.scts
-	state.OCSPResponse = c.ocspResponse
-	if !c.didResume && c.vers != VersionTLS13 {
-		if c.clientFinishedIsFirst {
-			state.TLSUnique = c.clientFinished[:]
-		} else {
-			state.TLSUnique = c.serverFinished[:]
-		}
-	}
-	if c.config.Renegotiation != RenegotiateNever {
-		state.ekm = noExportedKeyingMaterial
-	} else {
-		state.ekm = c.ekm
-	}
-	return state
-}
-
-// OCSPResponse returns the stapled OCSP response from the TLS server, if
-// any. (Only valid for client connections.)
-func (c *Conn) OCSPResponse() []byte {
-	c.handshakeMutex.Lock()
-	defer c.handshakeMutex.Unlock()
-
-	return c.ocspResponse
-}
-
-// VerifyHostname checks that the peer certificate chain is valid for
-// connecting to host. If so, it returns nil; if not, it returns an error
-// describing the problem.
-func (c *Conn) VerifyHostname(host string) error {
-	c.handshakeMutex.Lock()
-	defer c.handshakeMutex.Unlock()
-	if !c.isClient {
-		return errors.New("tls: VerifyHostname called on TLS server connection")
-	}
-	if !c.handshakeComplete() {
-		return errors.New("tls: handshake has not yet been performed")
-	}
-	if len(c.verifiedChains) == 0 {
-		return errors.New("tls: handshake did not verify certificate chain")
-	}
-	return c.peerCertificates[0].VerifyHostname(host)
-}
-
-func (c *Conn) handshakeComplete() bool {
-	return atomic.LoadUint32(&c.handshakeStatus) == 1
-}
diff --git a/contrib/go/_std_1.18/src/crypto/tls/handshake_client.go b/contrib/go/_std_1.18/src/crypto/tls/handshake_client.go
deleted file mode 100644
index a3e00777f1..0000000000
--- a/contrib/go/_std_1.18/src/crypto/tls/handshake_client.go
+++ /dev/null
@@ -1,1011 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package tls
-
-import (
-	"bytes"
-	"context"
-	"crypto"
-	"crypto/ecdsa"
-	"crypto/ed25519"
-	"crypto/rsa"
-	"crypto/subtle"
-	"crypto/x509"
-	"errors"
-	"fmt"
-	"hash"
-	"io"
-	"net"
-	"strings"
-	"sync/atomic"
-	"time"
-)
-
-type clientHandshakeState struct {
-	c            *Conn
-	ctx          context.Context
-	serverHello  *serverHelloMsg
-	hello        *clientHelloMsg
-	suite        *cipherSuite
-	finishedHash finishedHash
-	masterSecret []byte
-	session      *ClientSessionState
-}
-
-func (c *Conn) makeClientHello() (*clientHelloMsg, ecdheParameters, error) {
-	config := c.config
-	if len(config.ServerName) == 0 && !config.InsecureSkipVerify {
-		return nil, nil, errors.New("tls: either ServerName or InsecureSkipVerify must be specified in the tls.Config")
-	}
-
-	nextProtosLength := 0
-	for _, proto := range config.NextProtos {
-		if l := len(proto); l == 0 || l > 255 {
-			return nil, nil, errors.New("tls: invalid NextProtos value")
-		} else {
-			nextProtosLength += 1 + l
-		}
-	}
-	if nextProtosLength > 0xffff {
-		return nil, nil, errors.New("tls: NextProtos values too large")
-	}
-
-	supportedVersions := config.supportedVersions(roleClient)
-	if len(supportedVersions) == 0 {
-		return nil, nil, errors.New("tls: no supported versions satisfy MinVersion and MaxVersion")
-	}
-
-	clientHelloVersion := config.maxSupportedVersion(roleClient)
-	// The version at the beginning of the ClientHello was capped at TLS 1.2
-	// for compatibility reasons. The supported_versions extension is used
-	// to negotiate versions now. See RFC 8446, Section 4.2.1.
-	if clientHelloVersion > VersionTLS12 {
-		clientHelloVersion = VersionTLS12
-	}
-
-	hello := &clientHelloMsg{
-		vers:                         clientHelloVersion,
-		compressionMethods:           []uint8{compressionNone},
-		random:                       make([]byte, 32),
-		sessionId:                    make([]byte, 32),
-		ocspStapling:                 true,
-		scts:                         true,
-		serverName:                   hostnameInSNI(config.ServerName),
-		supportedCurves:              config.curvePreferences(),
-		supportedPoints:              []uint8{pointFormatUncompressed},
-		secureRenegotiationSupported: true,
-		alpnProtocols:                config.NextProtos,
-		supportedVersions:            supportedVersions,
-	}
-
-	if c.handshakes > 0 {
-		hello.secureRenegotiation = c.clientFinished[:]
-	}
-
-	preferenceOrder := cipherSuitesPreferenceOrder
-	if !hasAESGCMHardwareSupport {
-		preferenceOrder = cipherSuitesPreferenceOrderNoAES
-	}
-	configCipherSuites := config.cipherSuites()
-	hello.cipherSuites = make([]uint16, 0, len(configCipherSuites))
-
-	for _, suiteId := range preferenceOrder {
-		suite := mutualCipherSuite(configCipherSuites, suiteId)
-		if suite == nil {
-			continue
-		}
-		// Don't advertise TLS 1.2-only cipher suites unless
-		// we're attempting TLS 1.2.
-		if hello.vers < VersionTLS12 && suite.flags&suiteTLS12 != 0 {
-			continue
-		}
-		hello.cipherSuites = append(hello.cipherSuites, suiteId)
-	}
-
-	_, err := io.ReadFull(config.rand(), hello.random)
-	if err != nil {
-		return nil, nil, errors.New("tls: short read from Rand: " + err.Error())
-	}
-
-	// A random session ID is used to detect when the server accepted a ticket
-	// and is resuming a session (see RFC 5077). In TLS 1.3, it's always set as
-	// a compatibility measure (see RFC 8446, Section 4.1.2).
-	if _, err := io.ReadFull(config.rand(), hello.sessionId); err != nil {
-		return nil, nil, errors.New("tls: short read from Rand: " + err.Error())
-	}
-
-	if hello.vers >= VersionTLS12 {
-		hello.supportedSignatureAlgorithms = supportedSignatureAlgorithms
-	}
-
-	var params ecdheParameters
-	if hello.supportedVersions[0] == VersionTLS13 {
-		if hasAESGCMHardwareSupport {
-			hello.cipherSuites = append(hello.cipherSuites, defaultCipherSuitesTLS13...)
-		} else {
-			hello.cipherSuites = append(hello.cipherSuites, defaultCipherSuitesTLS13NoAES...)
-		}
-
-		curveID := config.curvePreferences()[0]
-		if _, ok := curveForCurveID(curveID); curveID != X25519 && !ok {
-			return nil, nil, errors.New("tls: CurvePreferences includes unsupported curve")
-		}
-		params, err = generateECDHEParameters(config.rand(), curveID)
-		if err != nil {
-			return nil, nil, err
-		}
-		hello.keyShares = []keyShare{{group: curveID, data: params.PublicKey()}}
-	}
-
-	return hello, params, nil
-}
-
-func (c *Conn) clientHandshake(ctx context.Context) (err error) {
-	if c.config == nil {
-		c.config = defaultConfig()
-	}
-
-	// This may be a renegotiation handshake, in which case some fields
-	// need to be reset.
-	c.didResume = false
-
-	hello, ecdheParams, err := c.makeClientHello()
-	if err != nil {
-		return err
-	}
-	c.serverName = hello.serverName
-
-	cacheKey, session, earlySecret, binderKey := c.loadSession(hello)
-	if cacheKey != "" && session != nil {
-		defer func() {
-			// If we got a handshake failure when resuming a session, throw away
-			// the session ticket. See RFC 5077, Section 3.2.
-			//
-			// RFC 8446 makes no mention of dropping tickets on failure, but it
-			// does require servers to abort on invalid binders, so we need to
-			// delete tickets to recover from a corrupted PSK.
-			if err != nil {
-				c.config.ClientSessionCache.Put(cacheKey, nil)
-			}
-		}()
-	}
-
-	if _, err := c.writeRecord(recordTypeHandshake, hello.marshal()); err != nil {
-		return err
-	}
-
-	msg, err := c.readHandshake()
-	if err != nil {
-		return err
-	}
-
-	serverHello, ok := msg.(*serverHelloMsg)
-	if !ok {
-		c.sendAlert(alertUnexpectedMessage)
-		return unexpectedMessageError(serverHello, msg)
-	}
-
-	if err := c.pickTLSVersion(serverHello); err != nil {
-		return err
-	}
-
-	// If we are negotiating a protocol version that's lower than what we
-	// support, check for the server downgrade canaries.
-	// See RFC 8446, Section 4.1.3.
-	maxVers := c.config.maxSupportedVersion(roleClient)
-	tls12Downgrade := string(serverHello.random[24:]) == downgradeCanaryTLS12
-	tls11Downgrade := string(serverHello.random[24:]) == downgradeCanaryTLS11
-	if maxVers == VersionTLS13 && c.vers <= VersionTLS12 && (tls12Downgrade || tls11Downgrade) ||
-		maxVers == VersionTLS12 && c.vers <= VersionTLS11 && tls11Downgrade {
-		c.sendAlert(alertIllegalParameter)
-		return errors.New("tls: downgrade attempt detected, possibly due to a MitM attack or a broken middlebox")
-	}
-
-	if c.vers == VersionTLS13 {
-		hs := &clientHandshakeStateTLS13{
-			c:           c,
-			ctx:         ctx,
-			serverHello: serverHello,
-			hello:       hello,
-			ecdheParams: ecdheParams,
-			session:     session,
-			earlySecret: earlySecret,
-			binderKey:   binderKey,
-		}
-
-		// In TLS 1.3, session tickets are delivered after the handshake.
-		return hs.handshake()
-	}
-
-	hs := &clientHandshakeState{
-		c:           c,
-		ctx:         ctx,
-		serverHello: serverHello,
-		hello:       hello,
-		session:     session,
-	}
-
-	if err := hs.handshake(); err != nil {
-		return err
-	}
-
-	// If we had a successful handshake and hs.session is different from
-	// the one already cached - cache a new one.
-	if cacheKey != "" && hs.session != nil && session != hs.session {
-		c.config.ClientSessionCache.Put(cacheKey, hs.session)
-	}
-
-	return nil
-}
-
-func (c *Conn) loadSession(hello *clientHelloMsg) (cacheKey string,
-	session *ClientSessionState, earlySecret, binderKey []byte) {
-	if c.config.SessionTicketsDisabled || c.config.ClientSessionCache == nil {
-		return "", nil, nil, nil
-	}
-
-	hello.ticketSupported = true
-
-	if hello.supportedVersions[0] == VersionTLS13 {
-		// Require DHE on resumption as it guarantees forward secrecy against
-		// compromise of the session ticket key. See RFC 8446, Section 4.2.9.
-		hello.pskModes = []uint8{pskModeDHE}
-	}
-
-	// Session resumption is not allowed if renegotiating because
-	// renegotiation is primarily used to allow a client to send a client
-	// certificate, which would be skipped if session resumption occurred.
-	if c.handshakes != 0 {
-		return "", nil, nil, nil
-	}
-
-	// Try to resume a previously negotiated TLS session, if available.
-	cacheKey = clientSessionCacheKey(c.conn.RemoteAddr(), c.config)
-	session, ok := c.config.ClientSessionCache.Get(cacheKey)
-	if !ok || session == nil {
-		return cacheKey, nil, nil, nil
-	}
-
-	// Check that version used for the previous session is still valid.
-	versOk := false
-	for _, v := range hello.supportedVersions {
-		if v == session.vers {
-			versOk = true
-			break
-		}
-	}
-	if !versOk {
-		return cacheKey, nil, nil, nil
-	}
-
-	// Check that the cached server certificate is not expired, and that it's
-	// valid for the ServerName. This should be ensured by the cache key, but
-	// protect the application from a faulty ClientSessionCache implementation.
-	if !c.config.InsecureSkipVerify {
-		if len(session.verifiedChains) == 0 {
-			// The original connection had InsecureSkipVerify, while this doesn't.
-			return cacheKey, nil, nil, nil
-		}
-		serverCert := session.serverCertificates[0]
-		if c.config.time().After(serverCert.NotAfter) {
-			// Expired certificate, delete the entry.
-			c.config.ClientSessionCache.Put(cacheKey, nil)
-			return cacheKey, nil, nil, nil
-		}
-		if err := serverCert.VerifyHostname(c.config.ServerName); err != nil {
-			return cacheKey, nil, nil, nil
-		}
-	}
-
-	if session.vers != VersionTLS13 {
-		// In TLS 1.2 the cipher suite must match the resumed session. Ensure we
-		// are still offering it.
-		if mutualCipherSuite(hello.cipherSuites, session.cipherSuite) == nil {
-			return cacheKey, nil, nil, nil
-		}
-
-		hello.sessionTicket = session.sessionTicket
-		return
-	}
-
-	// Check that the session ticket is not expired.
-	if c.config.time().After(session.useBy) {
-		c.config.ClientSessionCache.Put(cacheKey, nil)
-		return cacheKey, nil, nil, nil
-	}
-
-	// In TLS 1.3 the KDF hash must match the resumed session. Ensure we
-	// offer at least one cipher suite with that hash.
-	cipherSuite := cipherSuiteTLS13ByID(session.cipherSuite)
-	if cipherSuite == nil {
-		return cacheKey, nil, nil, nil
-	}
-	cipherSuiteOk := false
-	for _, offeredID := range hello.cipherSuites {
-		offeredSuite := cipherSuiteTLS13ByID(offeredID)
-		if offeredSuite != nil && offeredSuite.hash == cipherSuite.hash {
-			cipherSuiteOk = true
-			break
-		}
-	}
-	if !cipherSuiteOk {
-		return cacheKey, nil, nil, nil
-	}
-
-	// Set the pre_shared_key extension. See RFC 8446, Section 4.2.11.1.
-	ticketAge := uint32(c.config.time().Sub(session.receivedAt) / time.Millisecond)
-	identity := pskIdentity{
-		label:               session.sessionTicket,
-		obfuscatedTicketAge: ticketAge + session.ageAdd,
-	}
-	hello.pskIdentities = []pskIdentity{identity}
-	hello.pskBinders = [][]byte{make([]byte, cipherSuite.hash.Size())}
-
-	// Compute the PSK binders. See RFC 8446, Section 4.2.11.2.
-	psk := cipherSuite.expandLabel(session.masterSecret, "resumption",
-		session.nonce, cipherSuite.hash.Size())
-	earlySecret = cipherSuite.extract(psk, nil)
-	binderKey = cipherSuite.deriveSecret(earlySecret, resumptionBinderLabel, nil)
-	transcript := cipherSuite.hash.New()
-	transcript.Write(hello.marshalWithoutBinders())
-	pskBinders := [][]byte{cipherSuite.finishedHash(binderKey, transcript)}
-	hello.updateBinders(pskBinders)
-
-	return
-}
-
-func (c *Conn) pickTLSVersion(serverHello *serverHelloMsg) error {
-	peerVersion := serverHello.vers
-	if serverHello.supportedVersion != 0 {
-		peerVersion = serverHello.supportedVersion
-	}
-
-	vers, ok := c.config.mutualVersion(roleClient, []uint16{peerVersion})
-	if !ok {
-		c.sendAlert(alertProtocolVersion)
-		return fmt.Errorf("tls: server selected unsupported protocol version %x", peerVersion)
-	}
-
-	c.vers = vers
-	c.haveVers = true
-	c.in.version = vers
-	c.out.version = vers
-
-	return nil
-}
-
-// Does the handshake, either a full one or resumes old session. Requires hs.c,
-// hs.hello, hs.serverHello, and, optionally, hs.session to be set.
-func (hs *clientHandshakeState) handshake() error {
-	c := hs.c
-
-	isResume, err := hs.processServerHello()
-	if err != nil {
-		return err
-	}
-
-	hs.finishedHash = newFinishedHash(c.vers, hs.suite)
-
-	// No signatures of the handshake are needed in a resumption.
-	// Otherwise, in a full handshake, if we don't have any certificates
-	// configured then we will never send a CertificateVerify message and
-	// thus no signatures are needed in that case either.
-	if isResume || (len(c.config.Certificates) == 0 && c.config.GetClientCertificate == nil) {
-		hs.finishedHash.discardHandshakeBuffer()
-	}
-
-	hs.finishedHash.Write(hs.hello.marshal())
-	hs.finishedHash.Write(hs.serverHello.marshal())
-
-	c.buffering = true
-	c.didResume = isResume
-	if isResume {
-		if err := hs.establishKeys(); err != nil {
-			return err
-		}
-		if err := hs.readSessionTicket(); err != nil {
-			return err
-		}
-		if err := hs.readFinished(c.serverFinished[:]); err != nil {
-			return err
-		}
-		c.clientFinishedIsFirst = false
-		// Make sure the connection is still being verified whether or not this
-		// is a resumption. Resumptions currently don't reverify certificates so
-		// they don't call verifyServerCertificate. See Issue 31641.
-		if c.config.VerifyConnection != nil {
-			if err := c.config.VerifyConnection(c.connectionStateLocked()); err != nil {
-				c.sendAlert(alertBadCertificate)
-				return err
-			}
-		}
-		if err := hs.sendFinished(c.clientFinished[:]); err != nil {
-			return err
-		}
-		if _, err := c.flush(); err != nil {
-			return err
-		}
-	} else {
-		if err := hs.doFullHandshake(); err != nil {
-			return err
-		}
-		if err := hs.establishKeys(); err != nil {
-			return err
-		}
-		if err := hs.sendFinished(c.clientFinished[:]); err != nil {
-			return err
-		}
-		if _, err := c.flush(); err != nil {
-			return err
-		}
-		c.clientFinishedIsFirst = true
-		if err := hs.readSessionTicket(); err != nil {
-			return err
-		}
-		if err := hs.readFinished(c.serverFinished[:]); err != nil {
-			return err
-		}
-	}
-
-	c.ekm = ekmFromMasterSecret(c.vers, hs.suite, hs.masterSecret, hs.hello.random, hs.serverHello.random)
-	atomic.StoreUint32(&c.handshakeStatus, 1)
-
-	return nil
-}
-
-func (hs *clientHandshakeState) pickCipherSuite() error {
-	if hs.suite = mutualCipherSuite(hs.hello.cipherSuites, hs.serverHello.cipherSuite); hs.suite == nil {
-		hs.c.sendAlert(alertHandshakeFailure)
-		return errors.New("tls: server chose an unconfigured cipher suite")
-	}
-
-	hs.c.cipherSuite = hs.suite.id
-	return nil
-}
-
-func (hs *clientHandshakeState) doFullHandshake() error {
-	c := hs.c
-
-	msg, err := c.readHandshake()
-	if err != nil {
-		return err
-	}
-	certMsg, ok := msg.(*certificateMsg)
-	if !ok || len(certMsg.certificates) == 0 {
-		c.sendAlert(alertUnexpectedMessage)
-		return unexpectedMessageError(certMsg, msg)
-	}
-	hs.finishedHash.Write(certMsg.marshal())
-
-	msg, err = c.readHandshake()
-	if err != nil {
-		return err
-	}
-
-	cs, ok := msg.(*certificateStatusMsg)
-	if ok {
-		// RFC4366 on Certificate Status Request:
-		// The server MAY return a "certificate_status" message.
-
-		if !hs.serverHello.ocspStapling {
-			// If a server returns a "CertificateStatus" message, then the
-			// server MUST have included an extension of type "status_request"
-			// with empty "extension_data" in the extended server hello.
-
-			c.sendAlert(alertUnexpectedMessage)
-			return errors.New("tls: received unexpected CertificateStatus message")
-		}
-		hs.finishedHash.Write(cs.marshal())
-
-		c.ocspResponse = cs.response
-
-		msg, err = c.readHandshake()
-		if err != nil {
-			return err
-		}
-	}
-
-	if c.handshakes == 0 {
-		// If this is the first handshake on a connection, process and
-		// (optionally) verify the server's certificates.
-		if err := c.verifyServerCertificate(certMsg.certificates); err != nil {
-			return err
-		}
-	} else {
-		// This is a renegotiation handshake. We require that the
-		// server's identity (i.e. leaf certificate) is unchanged and
-		// thus any previous trust decision is still valid.
-		//
-		// See https://mitls.org/pages/attacks/3SHAKE for the
-		// motivation behind this requirement.
-		if !bytes.Equal(c.peerCertificates[0].Raw, certMsg.certificates[0]) {
-			c.sendAlert(alertBadCertificate)
-			return errors.New("tls: server's identity changed during renegotiation")
-		}
-	}
-
-	keyAgreement := hs.suite.ka(c.vers)
-
-	skx, ok := msg.(*serverKeyExchangeMsg)
-	if ok {
-		hs.finishedHash.Write(skx.marshal())
-		err = keyAgreement.processServerKeyExchange(c.config, hs.hello, hs.serverHello, c.peerCertificates[0], skx)
-		if err != nil {
-			c.sendAlert(alertUnexpectedMessage)
-			return err
-		}
-
-		msg, err = c.readHandshake()
-		if err != nil {
-			return err
-		}
-	}
-
-	var chainToSend *Certificate
-	var certRequested bool
-	certReq, ok := msg.(*certificateRequestMsg)
-	if ok {
-		certRequested = true
-		hs.finishedHash.Write(certReq.marshal())
-
-		cri := certificateRequestInfoFromMsg(hs.ctx, c.vers, certReq)
-		if chainToSend, err = c.getClientCertificate(cri); err != nil {
-			c.sendAlert(alertInternalError)
-			return err
-		}
-
-		msg, err = c.readHandshake()
-		if err != nil {
-			return err
-		}
-	}
-
-	shd, ok := msg.(*serverHelloDoneMsg)
-	if !ok {
-		c.sendAlert(alertUnexpectedMessage)
-		return unexpectedMessageError(shd, msg)
-	}
-	hs.finishedHash.Write(shd.marshal())
-
-	// If the server requested a certificate then we have to send a
-	// Certificate message, even if it's empty because we don't have a
-	// certificate to send.
-	if certRequested {
-		certMsg = new(certificateMsg)
-		certMsg.certificates = chainToSend.Certificate
-		hs.finishedHash.Write(certMsg.marshal())
-		if _, err := c.writeRecord(recordTypeHandshake, certMsg.marshal()); err != nil {
-			return err
-		}
-	}
-
-	preMasterSecret, ckx, err := keyAgreement.generateClientKeyExchange(c.config, hs.hello, c.peerCertificates[0])
-	if err != nil {
-		c.sendAlert(alertInternalError)
-		return err
-	}
-	if ckx != nil {
-		hs.finishedHash.Write(ckx.marshal())
-		if _, err := c.writeRecord(recordTypeHandshake, ckx.marshal()); err != nil {
-			return err
-		}
-	}
-
-	if chainToSend != nil && len(chainToSend.Certificate) > 0 {
-		certVerify := &certificateVerifyMsg{}
-
-		key, ok := chainToSend.PrivateKey.(crypto.Signer)
-		if !ok {
-			c.sendAlert(alertInternalError)
-			return fmt.Errorf("tls: client certificate private key of type %T does not implement crypto.Signer", chainToSend.PrivateKey)
-		}
-
-		var sigType uint8
-		var sigHash crypto.Hash
-		if c.vers >= VersionTLS12 {
-			signatureAlgorithm, err := selectSignatureScheme(c.vers, chainToSend, certReq.supportedSignatureAlgorithms)
-			if err != nil {
-				c.sendAlert(alertIllegalParameter)
-				return err
-			}
-			sigType, sigHash, err = typeAndHashFromSignatureScheme(signatureAlgorithm)
-			if err != nil {
-				return c.sendAlert(alertInternalError)
-			}
-			certVerify.hasSignatureAlgorithm = true
-			certVerify.signatureAlgorithm = signatureAlgorithm
-		} else {
-			sigType, sigHash, err = legacyTypeAndHashFromPublicKey(key.Public())
-			if err != nil {
-				c.sendAlert(alertIllegalParameter)
-				return err
-			}
-		}
-
-		signed := hs.finishedHash.hashForClientCertificate(sigType, sigHash, hs.masterSecret)
-		signOpts := crypto.SignerOpts(sigHash)
-		if sigType == signatureRSAPSS {
-			signOpts = &rsa.PSSOptions{SaltLength: rsa.PSSSaltLengthEqualsHash, Hash: sigHash}
-		}
-		certVerify.signature, err = key.Sign(c.config.rand(), signed, signOpts)
-		if err != nil {
-			c.sendAlert(alertInternalError)
-			return err
-		}
-
-		hs.finishedHash.Write(certVerify.marshal())
-		if _, err := c.writeRecord(recordTypeHandshake, certVerify.marshal()); err != nil {
-			return err
-		}
-	}
-
-	hs.masterSecret = masterFromPreMasterSecret(c.vers, hs.suite, preMasterSecret, hs.hello.random, hs.serverHello.random)
-	if err := c.config.writeKeyLog(keyLogLabelTLS12, hs.hello.random, hs.masterSecret); err != nil {
-		c.sendAlert(alertInternalError)
-		return errors.New("tls: failed to write to key log: " + err.Error())
-	}
-
-	hs.finishedHash.discardHandshakeBuffer()
-
-	return nil
-}
-
-func (hs *clientHandshakeState) establishKeys() error {
-	c := hs.c
-
-	clientMAC, serverMAC, clientKey, serverKey, clientIV, serverIV :=
-		keysFromMasterSecret(c.vers, hs.suite, hs.masterSecret, hs.hello.random, hs.serverHello.random, hs.suite.macLen, hs.suite.keyLen, hs.suite.ivLen)
-	var clientCipher, serverCipher any
-	var clientHash, serverHash hash.Hash
-	if hs.suite.cipher != nil {
-		clientCipher = hs.suite.cipher(clientKey, clientIV, false /* not for reading */)
-		clientHash = hs.suite.mac(clientMAC)
-		serverCipher = hs.suite.cipher(serverKey, serverIV, true /* for reading */)
-		serverHash = hs.suite.mac(serverMAC)
-	} else {
-		clientCipher = hs.suite.aead(clientKey, clientIV)
-		serverCipher = hs.suite.aead(serverKey, serverIV)
-	}
-
-	c.in.prepareCipherSpec(c.vers, serverCipher, serverHash)
-	c.out.prepareCipherSpec(c.vers, clientCipher, clientHash)
-	return nil
-}
-
-func (hs *clientHandshakeState) serverResumedSession() bool {
-	// If the server responded with the same sessionId then it means the
-	// sessionTicket is being used to resume a TLS session.
-	return hs.session != nil && hs.hello.sessionId != nil &&
-		bytes.Equal(hs.serverHello.sessionId, hs.hello.sessionId)
-}
-
-func (hs *clientHandshakeState) processServerHello() (bool, error) {
-	c := hs.c
-
-	if err := hs.pickCipherSuite(); err != nil {
-		return false, err
-	}
-
-	if hs.serverHello.compressionMethod != compressionNone {
-		c.sendAlert(alertUnexpectedMessage)
-		return false, errors.New("tls: server selected unsupported compression format")
-	}
-
-	if c.handshakes == 0 && hs.serverHello.secureRenegotiationSupported {
-		c.secureRenegotiation = true
-		if len(hs.serverHello.secureRenegotiation) != 0 {
-			c.sendAlert(alertHandshakeFailure)
-			return false, errors.New("tls: initial handshake had non-empty renegotiation extension")
-		}
-	}
-
-	if c.handshakes > 0 && c.secureRenegotiation {
-		var expectedSecureRenegotiation [24]byte
-		copy(expectedSecureRenegotiation[:], c.clientFinished[:])
-		copy(expectedSecureRenegotiation[12:], c.serverFinished[:])
-		if !bytes.Equal(hs.serverHello.secureRenegotiation, expectedSecureRenegotiation[:]) {
-			c.sendAlert(alertHandshakeFailure)
-			return false, errors.New("tls: incorrect renegotiation extension contents")
-		}
-	}
-
-	if err := checkALPN(hs.hello.alpnProtocols, hs.serverHello.alpnProtocol); err != nil {
-		c.sendAlert(alertUnsupportedExtension)
-		return false, err
-	}
-	c.clientProtocol = hs.serverHello.alpnProtocol
-
-	c.scts = hs.serverHello.scts
-
-	if !hs.serverResumedSession() {
-		return false, nil
-	}
-
-	if hs.session.vers != c.vers {
-		c.sendAlert(alertHandshakeFailure)
-		return false, errors.New("tls: server resumed a session with a different version")
-	}
-
-	if hs.session.cipherSuite != hs.suite.id {
-		c.sendAlert(alertHandshakeFailure)
-		return false, errors.New("tls: server resumed a session with a different cipher suite")
-	}
-
-	// Restore masterSecret, peerCerts, and ocspResponse from previous state
-	hs.masterSecret = hs.session.masterSecret
-	c.peerCertificates = hs.session.serverCertificates
-	c.verifiedChains = hs.session.verifiedChains
-	c.ocspResponse = hs.session.ocspResponse
-	// Let the ServerHello SCTs override the session SCTs from the original
-	// connection, if any are provided
-	if len(c.scts) == 0 && len(hs.session.scts) != 0 {
-		c.scts = hs.session.scts
-	}
-
-	return true, nil
-}
-
-// checkALPN ensure that the server's choice of ALPN protocol is compatible with
-// the protocols that we advertised in the Client Hello.
-func checkALPN(clientProtos []string, serverProto string) error {
-	if serverProto == "" {
-		return nil
-	}
-	if len(clientProtos) == 0 {
-		return errors.New("tls: server advertised unrequested ALPN extension")
-	}
-	for _, proto := range clientProtos {
-		if proto == serverProto {
-			return nil
-		}
-	}
-	return errors.New("tls: server selected unadvertised ALPN protocol")
-}
-
-func (hs *clientHandshakeState) readFinished(out []byte) error {
-	c := hs.c
-
-	if err := c.readChangeCipherSpec(); err != nil {
-		return err
-	}
-
-	msg, err := c.readHandshake()
-	if err != nil {
-		return err
-	}
-	serverFinished, ok := msg.(*finishedMsg)
-	if !ok {
-		c.sendAlert(alertUnexpectedMessage)
-		return unexpectedMessageError(serverFinished, msg)
-	}
-
-	verify := hs.finishedHash.serverSum(hs.masterSecret)
-	if len(verify) != len(serverFinished.verifyData) ||
-		subtle.ConstantTimeCompare(verify, serverFinished.verifyData) != 1 {
-		c.sendAlert(alertHandshakeFailure)
-		return errors.New("tls: server's Finished message was incorrect")
-	}
-	hs.finishedHash.Write(serverFinished.marshal())
-	copy(out, verify)
-	return nil
-}
-
-func (hs *clientHandshakeState) readSessionTicket() error {
-	if !hs.serverHello.ticketSupported {
-		return nil
-	}
-
-	c := hs.c
-	msg, err := c.readHandshake()
-	if err != nil {
-		return err
-	}
-	sessionTicketMsg, ok := msg.(*newSessionTicketMsg)
-	if !ok {
-		c.sendAlert(alertUnexpectedMessage)
-		return unexpectedMessageError(sessionTicketMsg, msg)
-	}
-	hs.finishedHash.Write(sessionTicketMsg.marshal())
-
-	hs.session = &ClientSessionState{
-		sessionTicket:      sessionTicketMsg.ticket,
-		vers:               c.vers,
-		cipherSuite:        hs.suite.id,
-		masterSecret:       hs.masterSecret,
-		serverCertificates: c.peerCertificates,
-		verifiedChains:     c.verifiedChains,
-		receivedAt:         c.config.time(),
-		ocspResponse:       c.ocspResponse,
-		scts:               c.scts,
-	}
-
-	return nil
-}
-
-func (hs *clientHandshakeState) sendFinished(out []byte) error {
-	c := hs.c
-
-	if _, err := c.writeRecord(recordTypeChangeCipherSpec, []byte{1}); err != nil {
-		return err
-	}
-
-	finished := new(finishedMsg)
-	finished.verifyData = hs.finishedHash.clientSum(hs.masterSecret)
-	hs.finishedHash.Write(finished.marshal())
-	if _, err := c.writeRecord(recordTypeHandshake, finished.marshal()); err != nil {
-		return err
-	}
-	copy(out, finished.verifyData)
-	return nil
-}
-
-// verifyServerCertificate parses and verifies the provided chain, setting
-// c.verifiedChains and c.peerCertificates or sending the appropriate alert.
-func (c *Conn) verifyServerCertificate(certificates [][]byte) error {
-	certs := make([]*x509.Certificate, len(certificates))
-	for i, asn1Data := range certificates {
-		cert, err := x509.ParseCertificate(asn1Data)
-		if err != nil {
-			c.sendAlert(alertBadCertificate)
-			return errors.New("tls: failed to parse certificate from server: " + err.Error())
-		}
-		certs[i] = cert
-	}
-
-	if !c.config.InsecureSkipVerify {
-		opts := x509.VerifyOptions{
-			Roots:         c.config.RootCAs,
-			CurrentTime:   c.config.time(),
-			DNSName:       c.config.ServerName,
-			Intermediates: x509.NewCertPool(),
-		}
-		for _, cert := range certs[1:] {
-			opts.Intermediates.AddCert(cert)
-		}
-		var err error
-		c.verifiedChains, err = certs[0].Verify(opts)
-		if err != nil {
-			c.sendAlert(alertBadCertificate)
-			return err
-		}
-	}
-
-	switch certs[0].PublicKey.(type) {
-	case *rsa.PublicKey, *ecdsa.PublicKey, ed25519.PublicKey:
-		break
-	default:
-		c.sendAlert(alertUnsupportedCertificate)
-		return fmt.Errorf("tls: server's certificate contains an unsupported type of public key: %T", certs[0].PublicKey)
-	}
-
-	c.peerCertificates = certs
-
-	if c.config.VerifyPeerCertificate != nil {
-		if err := c.config.VerifyPeerCertificate(certificates, c.verifiedChains); err != nil {
-			c.sendAlert(alertBadCertificate)
-			return err
-		}
-	}
-
-	if c.config.VerifyConnection != nil {
-		if err := c.config.VerifyConnection(c.connectionStateLocked()); err != nil {
-			c.sendAlert(alertBadCertificate)
-			return err
-		}
-	}
-
-	return nil
-}
-
-// certificateRequestInfoFromMsg generates a CertificateRequestInfo from a TLS
-// <= 1.2 CertificateRequest, making an effort to fill in missing information.
-func certificateRequestInfoFromMsg(ctx context.Context, vers uint16, certReq *certificateRequestMsg) *CertificateRequestInfo {
-	cri := &CertificateRequestInfo{
-		AcceptableCAs: certReq.certificateAuthorities,
-		Version:       vers,
-		ctx:           ctx,
-	}
-
-	var rsaAvail, ecAvail bool
-	for _, certType := range certReq.certificateTypes {
-		switch certType {
-		case certTypeRSASign:
-			rsaAvail = true
-		case certTypeECDSASign:
-			ecAvail = true
-		}
-	}
-
-	if !certReq.hasSignatureAlgorithm {
-		// Prior to TLS 1.2, signature schemes did not exist. In this case we
-		// make up a list based on the acceptable certificate types, to help
-		// GetClientCertificate and SupportsCertificate select the right certificate.
-		// The hash part of the SignatureScheme is a lie here, because
-		// TLS 1.0 and 1.1 always use MD5+SHA1 for RSA and SHA1 for ECDSA.
-		switch {
-		case rsaAvail && ecAvail:
-			cri.SignatureSchemes = []SignatureScheme{
-				ECDSAWithP256AndSHA256, ECDSAWithP384AndSHA384, ECDSAWithP521AndSHA512,
-				PKCS1WithSHA256, PKCS1WithSHA384, PKCS1WithSHA512, PKCS1WithSHA1,
-			}
-		case rsaAvail:
-			cri.SignatureSchemes = []SignatureScheme{
-				PKCS1WithSHA256, PKCS1WithSHA384, PKCS1WithSHA512, PKCS1WithSHA1,
-			}
-		case ecAvail:
-			cri.SignatureSchemes = []SignatureScheme{
-				ECDSAWithP256AndSHA256, ECDSAWithP384AndSHA384, ECDSAWithP521AndSHA512,
-			}
-		}
-		return cri
-	}
-
-	// Filter the signature schemes based on the certificate types.
-	// See RFC 5246, Section 7.4.4 (where it calls this "somewhat complicated").
-	cri.SignatureSchemes = make([]SignatureScheme, 0, len(certReq.supportedSignatureAlgorithms))
-	for _, sigScheme := range certReq.supportedSignatureAlgorithms {
-		sigType, _, err := typeAndHashFromSignatureScheme(sigScheme)
-		if err != nil {
-			continue
-		}
-		switch sigType {
-		case signatureECDSA, signatureEd25519:
-			if ecAvail {
-				cri.SignatureSchemes = append(cri.SignatureSchemes, sigScheme)
-			}
-		case signatureRSAPSS, signaturePKCS1v15:
-			if rsaAvail {
-				cri.SignatureSchemes = append(cri.SignatureSchemes, sigScheme)
-			}
-		}
-	}
-
-	return cri
-}
-
-func (c *Conn) getClientCertificate(cri *CertificateRequestInfo) (*Certificate, error) {
-	if c.config.GetClientCertificate != nil {
-		return c.config.GetClientCertificate(cri)
-	}
-
-	for _, chain := range c.config.Certificates {
-		if err := cri.SupportsCertificate(&chain); err != nil {
-			continue
-		}
-		return &chain, nil
-	}
-
-	// No acceptable certificate found. Don't send a certificate.
-	return new(Certificate), nil
-}
-
-// clientSessionCacheKey returns a key used to cache sessionTickets that could
-// be used to resume previously negotiated TLS sessions with a server.
-func clientSessionCacheKey(serverAddr net.Addr, config *Config) string {
-	if len(config.ServerName) > 0 {
-		return config.ServerName
-	}
-	return serverAddr.String()
-}
-
-// hostnameInSNI converts name into an appropriate hostname for SNI.
-// Literal IP addresses and absolute FQDNs are not permitted as SNI values.
-// See RFC 6066, Section 3.
-func hostnameInSNI(name string) string {
-	host := name
-	if len(host) > 0 && host[0] == '[' && host[len(host)-1] == ']' {
-		host = host[1 : len(host)-1]
-	}
-	if i := strings.LastIndex(host, "%"); i > 0 {
-		host = host[:i]
-	}
-	if net.ParseIP(host) != nil {
-		return ""
-	}
-	for len(name) > 0 && name[len(name)-1] == '.' {
-		name = name[:len(name)-1]
-	}
-	return name
-}
diff --git a/contrib/go/_std_1.18/src/crypto/tls/handshake_client_tls13.go b/contrib/go/_std_1.18/src/crypto/tls/handshake_client_tls13.go
deleted file mode 100644
index eb59ac90d1..0000000000
--- a/contrib/go/_std_1.18/src/crypto/tls/handshake_client_tls13.go
+++ /dev/null
@@ -1,682 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package tls
-
-import (
-	"bytes"
-	"context"
-	"crypto"
-	"crypto/hmac"
-	"crypto/rsa"
-	"errors"
-	"hash"
-	"sync/atomic"
-	"time"
-)
-
-type clientHandshakeStateTLS13 struct {
-	c           *Conn
-	ctx         context.Context
-	serverHello *serverHelloMsg
-	hello       *clientHelloMsg
-	ecdheParams ecdheParameters
-
-	session     *ClientSessionState
-	earlySecret []byte
-	binderKey   []byte
-
-	certReq       *certificateRequestMsgTLS13
-	usingPSK      bool
-	sentDummyCCS  bool
-	suite         *cipherSuiteTLS13
-	transcript    hash.Hash
-	masterSecret  []byte
-	trafficSecret []byte // client_application_traffic_secret_0
-}
-
-// handshake requires hs.c, hs.hello, hs.serverHello, hs.ecdheParams, and,
-// optionally, hs.session, hs.earlySecret and hs.binderKey to be set.
-func (hs *clientHandshakeStateTLS13) handshake() error {
-	c := hs.c
-
-	// The server must not select TLS 1.3 in a renegotiation. See RFC 8446,
-	// sections 4.1.2 and 4.1.3.
-	if c.handshakes > 0 {
-		c.sendAlert(alertProtocolVersion)
-		return errors.New("tls: server selected TLS 1.3 in a renegotiation")
-	}
-
-	// Consistency check on the presence of a keyShare and its parameters.
-	if hs.ecdheParams == nil || len(hs.hello.keyShares) != 1 {
-		return c.sendAlert(alertInternalError)
-	}
-
-	if err := hs.checkServerHelloOrHRR(); err != nil {
-		return err
-	}
-
-	hs.transcript = hs.suite.hash.New()
-	hs.transcript.Write(hs.hello.marshal())
-
-	if bytes.Equal(hs.serverHello.random, helloRetryRequestRandom) {
-		if err := hs.sendDummyChangeCipherSpec(); err != nil {
-			return err
-		}
-		if err := hs.processHelloRetryRequest(); err != nil {
-			return err
-		}
-	}
-
-	hs.transcript.Write(hs.serverHello.marshal())
-
-	c.buffering = true
-	if err := hs.processServerHello(); err != nil {
-		return err
-	}
-	if err := hs.sendDummyChangeCipherSpec(); err != nil {
-		return err
-	}
-	if err := hs.establishHandshakeKeys(); err != nil {
-		return err
-	}
-	if err := hs.readServerParameters(); err != nil {
-		return err
-	}
-	if err := hs.readServerCertificate(); err != nil {
-		return err
-	}
-	if err := hs.readServerFinished(); err != nil {
-		return err
-	}
-	if err := hs.sendClientCertificate(); err != nil {
-		return err
-	}
-	if err := hs.sendClientFinished(); err != nil {
-		return err
-	}
-	if _, err := c.flush(); err != nil {
-		return err
-	}
-
-	atomic.StoreUint32(&c.handshakeStatus, 1)
-
-	return nil
-}
-
-// checkServerHelloOrHRR does validity checks that apply to both ServerHello and
-// HelloRetryRequest messages. It sets hs.suite.
-func (hs *clientHandshakeStateTLS13) checkServerHelloOrHRR() error {
-	c := hs.c
-
-	if hs.serverHello.supportedVersion == 0 {
-		c.sendAlert(alertMissingExtension)
-		return errors.New("tls: server selected TLS 1.3 using the legacy version field")
-	}
-
-	if hs.serverHello.supportedVersion != VersionTLS13 {
-		c.sendAlert(alertIllegalParameter)
-		return errors.New("tls: server selected an invalid version after a HelloRetryRequest")
-	}
-
-	if hs.serverHello.vers != VersionTLS12 {
-		c.sendAlert(alertIllegalParameter)
-		return errors.New("tls: server sent an incorrect legacy version")
-	}
-
-	if hs.serverHello.ocspStapling ||
-		hs.serverHello.ticketSupported ||
-		hs.serverHello.secureRenegotiationSupported ||
-		len(hs.serverHello.secureRenegotiation) != 0 ||
-		len(hs.serverHello.alpnProtocol) != 0 ||
-		len(hs.serverHello.scts) != 0 {
-		c.sendAlert(alertUnsupportedExtension)
-		return errors.New("tls: server sent a ServerHello extension forbidden in TLS 1.3")
-	}
-
-	if !bytes.Equal(hs.hello.sessionId, hs.serverHello.sessionId) {
-		c.sendAlert(alertIllegalParameter)
-		return errors.New("tls: server did not echo the legacy session ID")
-	}
-
-	if hs.serverHello.compressionMethod != compressionNone {
-		c.sendAlert(alertIllegalParameter)
-		return errors.New("tls: server selected unsupported compression format")
-	}
-
-	selectedSuite := mutualCipherSuiteTLS13(hs.hello.cipherSuites, hs.serverHello.cipherSuite)
-	if hs.suite != nil && selectedSuite != hs.suite {
-		c.sendAlert(alertIllegalParameter)
-		return errors.New("tls: server changed cipher suite after a HelloRetryRequest")
-	}
-	if selectedSuite == nil {
-		c.sendAlert(alertIllegalParameter)
-		return errors.New("tls: server chose an unconfigured cipher suite")
-	}
-	hs.suite = selectedSuite
-	c.cipherSuite = hs.suite.id
-
-	return nil
-}
-
-// sendDummyChangeCipherSpec sends a ChangeCipherSpec record for compatibility
-// with middleboxes that didn't implement TLS correctly. See RFC 8446, Appendix D.4.
-func (hs *clientHandshakeStateTLS13) sendDummyChangeCipherSpec() error {
-	if hs.sentDummyCCS {
-		return nil
-	}
-	hs.sentDummyCCS = true
-
-	_, err := hs.c.writeRecord(recordTypeChangeCipherSpec, []byte{1})
-	return err
-}
-
-// processHelloRetryRequest handles the HRR in hs.serverHello, modifies and
-// resends hs.hello, and reads the new ServerHello into hs.serverHello.
-func (hs *clientHandshakeStateTLS13) processHelloRetryRequest() error {
-	c := hs.c
-
-	// The first ClientHello gets double-hashed into the transcript upon a
-	// HelloRetryRequest. (The idea is that the server might offload transcript
-	// storage to the client in the cookie.) See RFC 8446, Section 4.4.1.
-	chHash := hs.transcript.Sum(nil)
-	hs.transcript.Reset()
-	hs.transcript.Write([]byte{typeMessageHash, 0, 0, uint8(len(chHash))})
-	hs.transcript.Write(chHash)
-	hs.transcript.Write(hs.serverHello.marshal())
-
-	// The only HelloRetryRequest extensions we support are key_share and
-	// cookie, and clients must abort the handshake if the HRR would not result
-	// in any change in the ClientHello.
-	if hs.serverHello.selectedGroup == 0 && hs.serverHello.cookie == nil {
-		c.sendAlert(alertIllegalParameter)
-		return errors.New("tls: server sent an unnecessary HelloRetryRequest message")
-	}
-
-	if hs.serverHello.cookie != nil {
-		hs.hello.cookie = hs.serverHello.cookie
-	}
-
-	if hs.serverHello.serverShare.group != 0 {
-		c.sendAlert(alertDecodeError)
-		return errors.New("tls: received malformed key_share extension")
-	}
-
-	// If the server sent a key_share extension selecting a group, ensure it's
-	// a group we advertised but did not send a key share for, and send a key
-	// share for it this time.
-	if curveID := hs.serverHello.selectedGroup; curveID != 0 {
-		curveOK := false
-		for _, id := range hs.hello.supportedCurves {
-			if id == curveID {
-				curveOK = true
-				break
-			}
-		}
-		if !curveOK {
-			c.sendAlert(alertIllegalParameter)
-			return errors.New("tls: server selected unsupported group")
-		}
-		if hs.ecdheParams.CurveID() == curveID {
-			c.sendAlert(alertIllegalParameter)
-			return errors.New("tls: server sent an unnecessary HelloRetryRequest key_share")
-		}
-		if _, ok := curveForCurveID(curveID); curveID != X25519 && !ok {
-			c.sendAlert(alertInternalError)
-			return errors.New("tls: CurvePreferences includes unsupported curve")
-		}
-		params, err := generateECDHEParameters(c.config.rand(), curveID)
-		if err != nil {
-			c.sendAlert(alertInternalError)
-			return err
-		}
-		hs.ecdheParams = params
-		hs.hello.keyShares = []keyShare{{group: curveID, data: params.PublicKey()}}
-	}
-
-	hs.hello.raw = nil
-	if len(hs.hello.pskIdentities) > 0 {
-		pskSuite := cipherSuiteTLS13ByID(hs.session.cipherSuite)
-		if pskSuite == nil {
-			return c.sendAlert(alertInternalError)
-		}
-		if pskSuite.hash == hs.suite.hash {
-			// Update binders and obfuscated_ticket_age.
-			ticketAge := uint32(c.config.time().Sub(hs.session.receivedAt) / time.Millisecond)
-			hs.hello.pskIdentities[0].obfuscatedTicketAge = ticketAge + hs.session.ageAdd
-
-			transcript := hs.suite.hash.New()
-			transcript.Write([]byte{typeMessageHash, 0, 0, uint8(len(chHash))})
-			transcript.Write(chHash)
-			transcript.Write(hs.serverHello.marshal())
-			transcript.Write(hs.hello.marshalWithoutBinders())
-			pskBinders := [][]byte{hs.suite.finishedHash(hs.binderKey, transcript)}
-			hs.hello.updateBinders(pskBinders)
-		} else {
-			// Server selected a cipher suite incompatible with the PSK.
-			hs.hello.pskIdentities = nil
-			hs.hello.pskBinders = nil
-		}
-	}
-
-	hs.transcript.Write(hs.hello.marshal())
-	if _, err := c.writeRecord(recordTypeHandshake, hs.hello.marshal()); err != nil {
-		return err
-	}
-
-	msg, err := c.readHandshake()
-	if err != nil {
-		return err
-	}
-
-	serverHello, ok := msg.(*serverHelloMsg)
-	if !ok {
-		c.sendAlert(alertUnexpectedMessage)
-		return unexpectedMessageError(serverHello, msg)
-	}
-	hs.serverHello = serverHello
-
-	if err := hs.checkServerHelloOrHRR(); err != nil {
-		return err
-	}
-
-	return nil
-}
-
-func (hs *clientHandshakeStateTLS13) processServerHello() error {
-	c := hs.c
-
-	if bytes.Equal(hs.serverHello.random, helloRetryRequestRandom) {
-		c.sendAlert(alertUnexpectedMessage)
-		return errors.New("tls: server sent two HelloRetryRequest messages")
-	}
-
-	if len(hs.serverHello.cookie) != 0 {
-		c.sendAlert(alertUnsupportedExtension)
-		return errors.New("tls: server sent a cookie in a normal ServerHello")
-	}
-
-	if hs.serverHello.selectedGroup != 0 {
-		c.sendAlert(alertDecodeError)
-		return errors.New("tls: malformed key_share extension")
-	}
-
-	if hs.serverHello.serverShare.group == 0 {
-		c.sendAlert(alertIllegalParameter)
-		return errors.New("tls: server did not send a key share")
-	}
-	if hs.serverHello.serverShare.group != hs.ecdheParams.CurveID() {
-		c.sendAlert(alertIllegalParameter)
-		return errors.New("tls: server selected unsupported group")
-	}
-
-	if !hs.serverHello.selectedIdentityPresent {
-		return nil
-	}
-
-	if int(hs.serverHello.selectedIdentity) >= len(hs.hello.pskIdentities) {
-		c.sendAlert(alertIllegalParameter)
-		return errors.New("tls: server selected an invalid PSK")
-	}
-
-	if len(hs.hello.pskIdentities) != 1 || hs.session == nil {
-		return c.sendAlert(alertInternalError)
-	}
-	pskSuite := cipherSuiteTLS13ByID(hs.session.cipherSuite)
-	if pskSuite == nil {
-		return c.sendAlert(alertInternalError)
-	}
-	if pskSuite.hash != hs.suite.hash {
-		c.sendAlert(alertIllegalParameter)
-		return errors.New("tls: server selected an invalid PSK and cipher suite pair")
-	}
-
-	hs.usingPSK = true
-	c.didResume = true
-	c.peerCertificates = hs.session.serverCertificates
-	c.verifiedChains = hs.session.verifiedChains
-	c.ocspResponse = hs.session.ocspResponse
-	c.scts = hs.session.scts
-	return nil
-}
-
-func (hs *clientHandshakeStateTLS13) establishHandshakeKeys() error {
-	c := hs.c
-
-	sharedKey := hs.ecdheParams.SharedKey(hs.serverHello.serverShare.data)
-	if sharedKey == nil {
-		c.sendAlert(alertIllegalParameter)
-		return errors.New("tls: invalid server key share")
-	}
-
-	earlySecret := hs.earlySecret
-	if !hs.usingPSK {
-		earlySecret = hs.suite.extract(nil, nil)
-	}
-	handshakeSecret := hs.suite.extract(sharedKey,
-		hs.suite.deriveSecret(earlySecret, "derived", nil))
-
-	clientSecret := hs.suite.deriveSecret(handshakeSecret,
-		clientHandshakeTrafficLabel, hs.transcript)
-	c.out.setTrafficSecret(hs.suite, clientSecret)
-	serverSecret := hs.suite.deriveSecret(handshakeSecret,
-		serverHandshakeTrafficLabel, hs.transcript)
-	c.in.setTrafficSecret(hs.suite, serverSecret)
-
-	err := c.config.writeKeyLog(keyLogLabelClientHandshake, hs.hello.random, clientSecret)
-	if err != nil {
-		c.sendAlert(alertInternalError)
-		return err
-	}
-	err = c.config.writeKeyLog(keyLogLabelServerHandshake, hs.hello.random, serverSecret)
-	if err != nil {
-		c.sendAlert(alertInternalError)
-		return err
-	}
-
-	hs.masterSecret = hs.suite.extract(nil,
-		hs.suite.deriveSecret(handshakeSecret, "derived", nil))
-
-	return nil
-}
-
-func (hs *clientHandshakeStateTLS13) readServerParameters() error {
-	c := hs.c
-
-	msg, err := c.readHandshake()
-	if err != nil {
-		return err
-	}
-
-	encryptedExtensions, ok := msg.(*encryptedExtensionsMsg)
-	if !ok {
-		c.sendAlert(alertUnexpectedMessage)
-		return unexpectedMessageError(encryptedExtensions, msg)
-	}
-	hs.transcript.Write(encryptedExtensions.marshal())
-
-	if err := checkALPN(hs.hello.alpnProtocols, encryptedExtensions.alpnProtocol); err != nil {
-		c.sendAlert(alertUnsupportedExtension)
-		return err
-	}
-	c.clientProtocol = encryptedExtensions.alpnProtocol
-
-	return nil
-}
-
-func (hs *clientHandshakeStateTLS13) readServerCertificate() error {
-	c := hs.c
-
-	// Either a PSK or a certificate is always used, but not both.
-	// See RFC 8446, Section 4.1.1.
-	if hs.usingPSK {
-		// Make sure the connection is still being verified whether or not this
-		// is a resumption. Resumptions currently don't reverify certificates so
-		// they don't call verifyServerCertificate. See Issue 31641.
-		if c.config.VerifyConnection != nil {
-			if err := c.config.VerifyConnection(c.connectionStateLocked()); err != nil {
-				c.sendAlert(alertBadCertificate)
-				return err
-			}
-		}
-		return nil
-	}
-
-	msg, err := c.readHandshake()
-	if err != nil {
-		return err
-	}
-
-	certReq, ok := msg.(*certificateRequestMsgTLS13)
-	if ok {
-		hs.transcript.Write(certReq.marshal())
-
-		hs.certReq = certReq
-
-		msg, err = c.readHandshake()
-		if err != nil {
-			return err
-		}
-	}
-
-	certMsg, ok := msg.(*certificateMsgTLS13)
-	if !ok {
-		c.sendAlert(alertUnexpectedMessage)
-		return unexpectedMessageError(certMsg, msg)
-	}
-	if len(certMsg.certificate.Certificate) == 0 {
-		c.sendAlert(alertDecodeError)
-		return errors.New("tls: received empty certificates message")
-	}
-	hs.transcript.Write(certMsg.marshal())
-
-	c.scts = certMsg.certificate.SignedCertificateTimestamps
-	c.ocspResponse = certMsg.certificate.OCSPStaple
-
-	if err := c.verifyServerCertificate(certMsg.certificate.Certificate); err != nil {
-		return err
-	}
-
-	msg, err = c.readHandshake()
-	if err != nil {
-		return err
-	}
-
-	certVerify, ok := msg.(*certificateVerifyMsg)
-	if !ok {
-		c.sendAlert(alertUnexpectedMessage)
-		return unexpectedMessageError(certVerify, msg)
-	}
-
-	// See RFC 8446, Section 4.4.3.
-	if !isSupportedSignatureAlgorithm(certVerify.signatureAlgorithm, supportedSignatureAlgorithms) {
-		c.sendAlert(alertIllegalParameter)
-		return errors.New("tls: certificate used with invalid signature algorithm")
-	}
-	sigType, sigHash, err := typeAndHashFromSignatureScheme(certVerify.signatureAlgorithm)
-	if err != nil {
-		return c.sendAlert(alertInternalError)
-	}
-	if sigType == signaturePKCS1v15 || sigHash == crypto.SHA1 {
-		c.sendAlert(alertIllegalParameter)
-		return errors.New("tls: certificate used with invalid signature algorithm")
-	}
-	signed := signedMessage(sigHash, serverSignatureContext, hs.transcript)
-	if err := verifyHandshakeSignature(sigType, c.peerCertificates[0].PublicKey,
-		sigHash, signed, certVerify.signature); err != nil {
-		c.sendAlert(alertDecryptError)
-		return errors.New("tls: invalid signature by the server certificate: " + err.Error())
-	}
-
-	hs.transcript.Write(certVerify.marshal())
-
-	return nil
-}
-
-func (hs *clientHandshakeStateTLS13) readServerFinished() error {
-	c := hs.c
-
-	msg, err := c.readHandshake()
-	if err != nil {
-		return err
-	}
-
-	finished, ok := msg.(*finishedMsg)
-	if !ok {
-		c.sendAlert(alertUnexpectedMessage)
-		return unexpectedMessageError(finished, msg)
-	}
-
-	expectedMAC := hs.suite.finishedHash(c.in.trafficSecret, hs.transcript)
-	if !hmac.Equal(expectedMAC, finished.verifyData) {
-		c.sendAlert(alertDecryptError)
-		return errors.New("tls: invalid server finished hash")
-	}
-
-	hs.transcript.Write(finished.marshal())
-
-	// Derive secrets that take context through the server Finished.
-
-	hs.trafficSecret = hs.suite.deriveSecret(hs.masterSecret,
-		clientApplicationTrafficLabel, hs.transcript)
-	serverSecret := hs.suite.deriveSecret(hs.masterSecret,
-		serverApplicationTrafficLabel, hs.transcript)
-	c.in.setTrafficSecret(hs.suite, serverSecret)
-
-	err = c.config.writeKeyLog(keyLogLabelClientTraffic, hs.hello.random, hs.trafficSecret)
-	if err != nil {
-		c.sendAlert(alertInternalError)
-		return err
-	}
-	err = c.config.writeKeyLog(keyLogLabelServerTraffic, hs.hello.random, serverSecret)
-	if err != nil {
-		c.sendAlert(alertInternalError)
-		return err
-	}
-
-	c.ekm = hs.suite.exportKeyingMaterial(hs.masterSecret, hs.transcript)
-
-	return nil
-}
-
-func (hs *clientHandshakeStateTLS13) sendClientCertificate() error {
-	c := hs.c
-
-	if hs.certReq == nil {
-		return nil
-	}
-
-	cert, err := c.getClientCertificate(&CertificateRequestInfo{
-		AcceptableCAs:    hs.certReq.certificateAuthorities,
-		SignatureSchemes: hs.certReq.supportedSignatureAlgorithms,
-		Version:          c.vers,
-		ctx:              hs.ctx,
-	})
-	if err != nil {
-		return err
-	}
-
-	certMsg := new(certificateMsgTLS13)
-
-	certMsg.certificate = *cert
-	certMsg.scts = hs.certReq.scts && len(cert.SignedCertificateTimestamps) > 0
-	certMsg.ocspStapling = hs.certReq.ocspStapling && len(cert.OCSPStaple) > 0
-
-	hs.transcript.Write(certMsg.marshal())
-	if _, err := c.writeRecord(recordTypeHandshake, certMsg.marshal()); err != nil {
-		return err
-	}
-
-	// If we sent an empty certificate message, skip the CertificateVerify.
-	if len(cert.Certificate) == 0 {
-		return nil
-	}
-
-	certVerifyMsg := new(certificateVerifyMsg)
-	certVerifyMsg.hasSignatureAlgorithm = true
-
-	certVerifyMsg.signatureAlgorithm, err = selectSignatureScheme(c.vers, cert, hs.certReq.supportedSignatureAlgorithms)
-	if err != nil {
-		// getClientCertificate returned a certificate incompatible with the
-		// CertificateRequestInfo supported signature algorithms.
-		c.sendAlert(alertHandshakeFailure)
-		return err
-	}
-
-	sigType, sigHash, err := typeAndHashFromSignatureScheme(certVerifyMsg.signatureAlgorithm)
-	if err != nil {
-		return c.sendAlert(alertInternalError)
-	}
-
-	signed := signedMessage(sigHash, clientSignatureContext, hs.transcript)
-	signOpts := crypto.SignerOpts(sigHash)
-	if sigType == signatureRSAPSS {
-		signOpts = &rsa.PSSOptions{SaltLength: rsa.PSSSaltLengthEqualsHash, Hash: sigHash}
-	}
-	sig, err := cert.PrivateKey.(crypto.Signer).Sign(c.config.rand(), signed, signOpts)
-	if err != nil {
-		c.sendAlert(alertInternalError)
-		return errors.New("tls: failed to sign handshake: " + err.Error())
-	}
-	certVerifyMsg.signature = sig
-
-	hs.transcript.Write(certVerifyMsg.marshal())
-	if _, err := c.writeRecord(recordTypeHandshake, certVerifyMsg.marshal()); err != nil {
-		return err
-	}
-
-	return nil
-}
-
-func (hs *clientHandshakeStateTLS13) sendClientFinished() error {
-	c := hs.c
-
-	finished := &finishedMsg{
-		verifyData: hs.suite.finishedHash(c.out.trafficSecret, hs.transcript),
-	}
-
-	hs.transcript.Write(finished.marshal())
-	if _, err := c.writeRecord(recordTypeHandshake, finished.marshal()); err != nil {
-		return err
-	}
-
-	c.out.setTrafficSecret(hs.suite, hs.trafficSecret)
-
-	if !c.config.SessionTicketsDisabled && c.config.ClientSessionCache != nil {
-		c.resumptionSecret = hs.suite.deriveSecret(hs.masterSecret,
-			resumptionLabel, hs.transcript)
-	}
-
-	return nil
-}
-
-func (c *Conn) handleNewSessionTicket(msg *newSessionTicketMsgTLS13) error {
-	if !c.isClient {
-		c.sendAlert(alertUnexpectedMessage)
-		return errors.New("tls: received new session ticket from a client")
-	}
-
-	if c.config.SessionTicketsDisabled || c.config.ClientSessionCache == nil {
-		return nil
-	}
-
-	// See RFC 8446, Section 4.6.1.
-	if msg.lifetime == 0 {
-		return nil
-	}
-	lifetime := time.Duration(msg.lifetime) * time.Second
-	if lifetime > maxSessionTicketLifetime {
-		c.sendAlert(alertIllegalParameter)
-		return errors.New("tls: received a session ticket with invalid lifetime")
-	}
-
-	cipherSuite := cipherSuiteTLS13ByID(c.cipherSuite)
-	if cipherSuite == nil || c.resumptionSecret == nil {
-		return c.sendAlert(alertInternalError)
-	}
-
-	// Save the resumption_master_secret and nonce instead of deriving the PSK
-	// to do the least amount of work on NewSessionTicket messages before we
-	// know if the ticket will be used. Forward secrecy of resumed connections
-	// is guaranteed by the requirement for pskModeDHE.
-	session := &ClientSessionState{
-		sessionTicket:      msg.label,
-		vers:               c.vers,
-		cipherSuite:        c.cipherSuite,
-		masterSecret:       c.resumptionSecret,
-		serverCertificates: c.peerCertificates,
-		verifiedChains:     c.verifiedChains,
-		receivedAt:         c.config.time(),
-		nonce:              msg.nonce,
-		useBy:              c.config.time().Add(lifetime),
-		ageAdd:             msg.ageAdd,
-		ocspResponse:       c.ocspResponse,
-		scts:               c.scts,
-	}
-
-	cacheKey := clientSessionCacheKey(c.conn.RemoteAddr(), c.config)
-	c.config.ClientSessionCache.Put(cacheKey, session)
-
-	return nil
-}
diff --git a/contrib/go/_std_1.18/src/crypto/tls/handshake_messages.go b/contrib/go/_std_1.18/src/crypto/tls/handshake_messages.go
deleted file mode 100644
index 17cf85910f..0000000000
--- a/contrib/go/_std_1.18/src/crypto/tls/handshake_messages.go
+++ /dev/null
@@ -1,1808 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package tls
-
-import (
-	"fmt"
-	"strings"
-
-	"golang.org/x/crypto/cryptobyte"
-)
-
-// The marshalingFunction type is an adapter to allow the use of ordinary
-// functions as cryptobyte.MarshalingValue.
-type marshalingFunction func(b *cryptobyte.Builder) error
-
-func (f marshalingFunction) Marshal(b *cryptobyte.Builder) error {
-	return f(b)
-}
-
-// addBytesWithLength appends a sequence of bytes to the cryptobyte.Builder. If
-// the length of the sequence is not the value specified, it produces an error.
-func addBytesWithLength(b *cryptobyte.Builder, v []byte, n int) {
-	b.AddValue(marshalingFunction(func(b *cryptobyte.Builder) error {
-		if len(v) != n {
-			return fmt.Errorf("invalid value length: expected %d, got %d", n, len(v))
-		}
-		b.AddBytes(v)
-		return nil
-	}))
-}
-
-// addUint64 appends a big-endian, 64-bit value to the cryptobyte.Builder.
-func addUint64(b *cryptobyte.Builder, v uint64) {
-	b.AddUint32(uint32(v >> 32))
-	b.AddUint32(uint32(v))
-}
-
-// readUint64 decodes a big-endian, 64-bit value into out and advances over it.
-// It reports whether the read was successful.
-func readUint64(s *cryptobyte.String, out *uint64) bool {
-	var hi, lo uint32
-	if !s.ReadUint32(&hi) || !s.ReadUint32(&lo) {
-		return false
-	}
-	*out = uint64(hi)<<32 | uint64(lo)
-	return true
-}
-
-// readUint8LengthPrefixed acts like s.ReadUint8LengthPrefixed, but targets a
-// []byte instead of a cryptobyte.String.
-func readUint8LengthPrefixed(s *cryptobyte.String, out *[]byte) bool {
-	return s.ReadUint8LengthPrefixed((*cryptobyte.String)(out))
-}
-
-// readUint16LengthPrefixed acts like s.ReadUint16LengthPrefixed, but targets a
-// []byte instead of a cryptobyte.String.
-func readUint16LengthPrefixed(s *cryptobyte.String, out *[]byte) bool {
-	return s.ReadUint16LengthPrefixed((*cryptobyte.String)(out))
-}
-
-// readUint24LengthPrefixed acts like s.ReadUint24LengthPrefixed, but targets a
-// []byte instead of a cryptobyte.String.
-func readUint24LengthPrefixed(s *cryptobyte.String, out *[]byte) bool {
-	return s.ReadUint24LengthPrefixed((*cryptobyte.String)(out))
-}
-
-type clientHelloMsg struct {
-	raw                              []byte
-	vers                             uint16
-	random                           []byte
-	sessionId                        []byte
-	cipherSuites                     []uint16
-	compressionMethods               []uint8
-	serverName                       string
-	ocspStapling                     bool
-	supportedCurves                  []CurveID
-	supportedPoints                  []uint8
-	ticketSupported                  bool
-	sessionTicket                    []uint8
-	supportedSignatureAlgorithms     []SignatureScheme
-	supportedSignatureAlgorithmsCert []SignatureScheme
-	secureRenegotiationSupported     bool
-	secureRenegotiation              []byte
-	alpnProtocols                    []string
-	scts                             bool
-	supportedVersions                []uint16
-	cookie                           []byte
-	keyShares                        []keyShare
-	earlyData                        bool
-	pskModes                         []uint8
-	pskIdentities                    []pskIdentity
-	pskBinders                       [][]byte
-}
-
-func (m *clientHelloMsg) marshal() []byte {
-	if m.raw != nil {
-		return m.raw
-	}
-
-	var b cryptobyte.Builder
-	b.AddUint8(typeClientHello)
-	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
-		b.AddUint16(m.vers)
-		addBytesWithLength(b, m.random, 32)
-		b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
-			b.AddBytes(m.sessionId)
-		})
-		b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-			for _, suite := range m.cipherSuites {
-				b.AddUint16(suite)
-			}
-		})
-		b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
-			b.AddBytes(m.compressionMethods)
-		})
-
-		// If extensions aren't present, omit them.
-		var extensionsPresent bool
-		bWithoutExtensions := *b
-
-		b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-			if len(m.serverName) > 0 {
-				// RFC 6066, Section 3
-				b.AddUint16(extensionServerName)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-						b.AddUint8(0) // name_type = host_name
-						b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-							b.AddBytes([]byte(m.serverName))
-						})
-					})
-				})
-			}
-			if m.ocspStapling {
-				// RFC 4366, Section 3.6
-				b.AddUint16(extensionStatusRequest)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint8(1)  // status_type = ocsp
-					b.AddUint16(0) // empty responder_id_list
-					b.AddUint16(0) // empty request_extensions
-				})
-			}
-			if len(m.supportedCurves) > 0 {
-				// RFC 4492, sections 5.1.1 and RFC 8446, Section 4.2.7
-				b.AddUint16(extensionSupportedCurves)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-						for _, curve := range m.supportedCurves {
-							b.AddUint16(uint16(curve))
-						}
-					})
-				})
-			}
-			if len(m.supportedPoints) > 0 {
-				// RFC 4492, Section 5.1.2
-				b.AddUint16(extensionSupportedPoints)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
-						b.AddBytes(m.supportedPoints)
-					})
-				})
-			}
-			if m.ticketSupported {
-				// RFC 5077, Section 3.2
-				b.AddUint16(extensionSessionTicket)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddBytes(m.sessionTicket)
-				})
-			}
-			if len(m.supportedSignatureAlgorithms) > 0 {
-				// RFC 5246, Section 7.4.1.4.1
-				b.AddUint16(extensionSignatureAlgorithms)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-						for _, sigAlgo := range m.supportedSignatureAlgorithms {
-							b.AddUint16(uint16(sigAlgo))
-						}
-					})
-				})
-			}
-			if len(m.supportedSignatureAlgorithmsCert) > 0 {
-				// RFC 8446, Section 4.2.3
-				b.AddUint16(extensionSignatureAlgorithmsCert)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-						for _, sigAlgo := range m.supportedSignatureAlgorithmsCert {
-							b.AddUint16(uint16(sigAlgo))
-						}
-					})
-				})
-			}
-			if m.secureRenegotiationSupported {
-				// RFC 5746, Section 3.2
-				b.AddUint16(extensionRenegotiationInfo)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
-						b.AddBytes(m.secureRenegotiation)
-					})
-				})
-			}
-			if len(m.alpnProtocols) > 0 {
-				// RFC 7301, Section 3.1
-				b.AddUint16(extensionALPN)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-						for _, proto := range m.alpnProtocols {
-							b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
-								b.AddBytes([]byte(proto))
-							})
-						}
-					})
-				})
-			}
-			if m.scts {
-				// RFC 6962, Section 3.3.1
-				b.AddUint16(extensionSCT)
-				b.AddUint16(0) // empty extension_data
-			}
-			if len(m.supportedVersions) > 0 {
-				// RFC 8446, Section 4.2.1
-				b.AddUint16(extensionSupportedVersions)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
-						for _, vers := range m.supportedVersions {
-							b.AddUint16(vers)
-						}
-					})
-				})
-			}
-			if len(m.cookie) > 0 {
-				// RFC 8446, Section 4.2.2
-				b.AddUint16(extensionCookie)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-						b.AddBytes(m.cookie)
-					})
-				})
-			}
-			if len(m.keyShares) > 0 {
-				// RFC 8446, Section 4.2.8
-				b.AddUint16(extensionKeyShare)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-						for _, ks := range m.keyShares {
-							b.AddUint16(uint16(ks.group))
-							b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-								b.AddBytes(ks.data)
-							})
-						}
-					})
-				})
-			}
-			if m.earlyData {
-				// RFC 8446, Section 4.2.10
-				b.AddUint16(extensionEarlyData)
-				b.AddUint16(0) // empty extension_data
-			}
-			if len(m.pskModes) > 0 {
-				// RFC 8446, Section 4.2.9
-				b.AddUint16(extensionPSKModes)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
-						b.AddBytes(m.pskModes)
-					})
-				})
-			}
-			if len(m.pskIdentities) > 0 { // pre_shared_key must be the last extension
-				// RFC 8446, Section 4.2.11
-				b.AddUint16(extensionPreSharedKey)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-						for _, psk := range m.pskIdentities {
-							b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-								b.AddBytes(psk.label)
-							})
-							b.AddUint32(psk.obfuscatedTicketAge)
-						}
-					})
-					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-						for _, binder := range m.pskBinders {
-							b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
-								b.AddBytes(binder)
-							})
-						}
-					})
-				})
-			}
-
-			extensionsPresent = len(b.BytesOrPanic()) > 2
-		})
-
-		if !extensionsPresent {
-			*b = bWithoutExtensions
-		}
-	})
-
-	m.raw = b.BytesOrPanic()
-	return m.raw
-}
-
-// marshalWithoutBinders returns the ClientHello through the
-// PreSharedKeyExtension.identities field, according to RFC 8446, Section
-// 4.2.11.2. Note that m.pskBinders must be set to slices of the correct length.
-func (m *clientHelloMsg) marshalWithoutBinders() []byte {
-	bindersLen := 2 // uint16 length prefix
-	for _, binder := range m.pskBinders {
-		bindersLen += 1 // uint8 length prefix
-		bindersLen += len(binder)
-	}
-
-	fullMessage := m.marshal()
-	return fullMessage[:len(fullMessage)-bindersLen]
-}
-
-// updateBinders updates the m.pskBinders field, if necessary updating the
-// cached marshaled representation. The supplied binders must have the same
-// length as the current m.pskBinders.
-func (m *clientHelloMsg) updateBinders(pskBinders [][]byte) {
-	if len(pskBinders) != len(m.pskBinders) {
-		panic("tls: internal error: pskBinders length mismatch")
-	}
-	for i := range m.pskBinders {
-		if len(pskBinders[i]) != len(m.pskBinders[i]) {
-			panic("tls: internal error: pskBinders length mismatch")
-		}
-	}
-	m.pskBinders = pskBinders
-	if m.raw != nil {
-		lenWithoutBinders := len(m.marshalWithoutBinders())
-		b := cryptobyte.NewFixedBuilder(m.raw[:lenWithoutBinders])
-		b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-			for _, binder := range m.pskBinders {
-				b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddBytes(binder)
-				})
-			}
-		})
-		if out, err := b.Bytes(); err != nil || len(out) != len(m.raw) {
-			panic("tls: internal error: failed to update binders")
-		}
-	}
-}
-
-func (m *clientHelloMsg) unmarshal(data []byte) bool {
-	*m = clientHelloMsg{raw: data}
-	s := cryptobyte.String(data)
-
-	if !s.Skip(4) || // message type and uint24 length field
-		!s.ReadUint16(&m.vers) || !s.ReadBytes(&m.random, 32) ||
-		!readUint8LengthPrefixed(&s, &m.sessionId) {
-		return false
-	}
-
-	var cipherSuites cryptobyte.String
-	if !s.ReadUint16LengthPrefixed(&cipherSuites) {
-		return false
-	}
-	m.cipherSuites = []uint16{}
-	m.secureRenegotiationSupported = false
-	for !cipherSuites.Empty() {
-		var suite uint16
-		if !cipherSuites.ReadUint16(&suite) {
-			return false
-		}
-		if suite == scsvRenegotiation {
-			m.secureRenegotiationSupported = true
-		}
-		m.cipherSuites = append(m.cipherSuites, suite)
-	}
-
-	if !readUint8LengthPrefixed(&s, &m.compressionMethods) {
-		return false
-	}
-
-	if s.Empty() {
-		// ClientHello is optionally followed by extension data
-		return true
-	}
-
-	var extensions cryptobyte.String
-	if !s.ReadUint16LengthPrefixed(&extensions) || !s.Empty() {
-		return false
-	}
-
-	for !extensions.Empty() {
-		var extension uint16
-		var extData cryptobyte.String
-		if !extensions.ReadUint16(&extension) ||
-			!extensions.ReadUint16LengthPrefixed(&extData) {
-			return false
-		}
-
-		switch extension {
-		case extensionServerName:
-			// RFC 6066, Section 3
-			var nameList cryptobyte.String
-			if !extData.ReadUint16LengthPrefixed(&nameList) || nameList.Empty() {
-				return false
-			}
-			for !nameList.Empty() {
-				var nameType uint8
-				var serverName cryptobyte.String
-				if !nameList.ReadUint8(&nameType) ||
-					!nameList.ReadUint16LengthPrefixed(&serverName) ||
-					serverName.Empty() {
-					return false
-				}
-				if nameType != 0 {
-					continue
-				}
-				if len(m.serverName) != 0 {
-					// Multiple names of the same name_type are prohibited.
-					return false
-				}
-				m.serverName = string(serverName)
-				// An SNI value may not include a trailing dot.
-				if strings.HasSuffix(m.serverName, ".") {
-					return false
-				}
-			}
-		case extensionStatusRequest:
-			// RFC 4366, Section 3.6
-			var statusType uint8
-			var ignored cryptobyte.String
-			if !extData.ReadUint8(&statusType) ||
-				!extData.ReadUint16LengthPrefixed(&ignored) ||
-				!extData.ReadUint16LengthPrefixed(&ignored) {
-				return false
-			}
-			m.ocspStapling = statusType == statusTypeOCSP
-		case extensionSupportedCurves:
-			// RFC 4492, sections 5.1.1 and RFC 8446, Section 4.2.7
-			var curves cryptobyte.String
-			if !extData.ReadUint16LengthPrefixed(&curves) || curves.Empty() {
-				return false
-			}
-			for !curves.Empty() {
-				var curve uint16
-				if !curves.ReadUint16(&curve) {
-					return false
-				}
-				m.supportedCurves = append(m.supportedCurves, CurveID(curve))
-			}
-		case extensionSupportedPoints:
-			// RFC 4492, Section 5.1.2
-			if !readUint8LengthPrefixed(&extData, &m.supportedPoints) ||
-				len(m.supportedPoints) == 0 {
-				return false
-			}
-		case extensionSessionTicket:
-			// RFC 5077, Section 3.2
-			m.ticketSupported = true
-			extData.ReadBytes(&m.sessionTicket, len(extData))
-		case extensionSignatureAlgorithms:
-			// RFC 5246, Section 7.4.1.4.1
-			var sigAndAlgs cryptobyte.String
-			if !extData.ReadUint16LengthPrefixed(&sigAndAlgs) || sigAndAlgs.Empty() {
-				return false
-			}
-			for !sigAndAlgs.Empty() {
-				var sigAndAlg uint16
-				if !sigAndAlgs.ReadUint16(&sigAndAlg) {
-					return false
-				}
-				m.supportedSignatureAlgorithms = append(
-					m.supportedSignatureAlgorithms, SignatureScheme(sigAndAlg))
-			}
-		case extensionSignatureAlgorithmsCert:
-			// RFC 8446, Section 4.2.3
-			var sigAndAlgs cryptobyte.String
-			if !extData.ReadUint16LengthPrefixed(&sigAndAlgs) || sigAndAlgs.Empty() {
-				return false
-			}
-			for !sigAndAlgs.Empty() {
-				var sigAndAlg uint16
-				if !sigAndAlgs.ReadUint16(&sigAndAlg) {
-					return false
-				}
-				m.supportedSignatureAlgorithmsCert = append(
-					m.supportedSignatureAlgorithmsCert, SignatureScheme(sigAndAlg))
-			}
-		case extensionRenegotiationInfo:
-			// RFC 5746, Section 3.2
-			if !readUint8LengthPrefixed(&extData, &m.secureRenegotiation) {
-				return false
-			}
-			m.secureRenegotiationSupported = true
-		case extensionALPN:
-			// RFC 7301, Section 3.1
-			var protoList cryptobyte.String
-			if !extData.ReadUint16LengthPrefixed(&protoList) || protoList.Empty() {
-				return false
-			}
-			for !protoList.Empty() {
-				var proto cryptobyte.String
-				if !protoList.ReadUint8LengthPrefixed(&proto) || proto.Empty() {
-					return false
-				}
-				m.alpnProtocols = append(m.alpnProtocols, string(proto))
-			}
-		case extensionSCT:
-			// RFC 6962, Section 3.3.1
-			m.scts = true
-		case extensionSupportedVersions:
-			// RFC 8446, Section 4.2.1
-			var versList cryptobyte.String
-			if !extData.ReadUint8LengthPrefixed(&versList) || versList.Empty() {
-				return false
-			}
-			for !versList.Empty() {
-				var vers uint16
-				if !versList.ReadUint16(&vers) {
-					return false
-				}
-				m.supportedVersions = append(m.supportedVersions, vers)
-			}
-		case extensionCookie:
-			// RFC 8446, Section 4.2.2
-			if !readUint16LengthPrefixed(&extData, &m.cookie) ||
-				len(m.cookie) == 0 {
-				return false
-			}
-		case extensionKeyShare:
-			// RFC 8446, Section 4.2.8
-			var clientShares cryptobyte.String
-			if !extData.ReadUint16LengthPrefixed(&clientShares) {
-				return false
-			}
-			for !clientShares.Empty() {
-				var ks keyShare
-				if !clientShares.ReadUint16((*uint16)(&ks.group)) ||
-					!readUint16LengthPrefixed(&clientShares, &ks.data) ||
-					len(ks.data) == 0 {
-					return false
-				}
-				m.keyShares = append(m.keyShares, ks)
-			}
-		case extensionEarlyData:
-			// RFC 8446, Section 4.2.10
-			m.earlyData = true
-		case extensionPSKModes:
-			// RFC 8446, Section 4.2.9
-			if !readUint8LengthPrefixed(&extData, &m.pskModes) {
-				return false
-			}
-		case extensionPreSharedKey:
-			// RFC 8446, Section 4.2.11
-			if !extensions.Empty() {
-				return false // pre_shared_key must be the last extension
-			}
-			var identities cryptobyte.String
-			if !extData.ReadUint16LengthPrefixed(&identities) || identities.Empty() {
-				return false
-			}
-			for !identities.Empty() {
-				var psk pskIdentity
-				if !readUint16LengthPrefixed(&identities, &psk.label) ||
-					!identities.ReadUint32(&psk.obfuscatedTicketAge) ||
-					len(psk.label) == 0 {
-					return false
-				}
-				m.pskIdentities = append(m.pskIdentities, psk)
-			}
-			var binders cryptobyte.String
-			if !extData.ReadUint16LengthPrefixed(&binders) || binders.Empty() {
-				return false
-			}
-			for !binders.Empty() {
-				var binder []byte
-				if !readUint8LengthPrefixed(&binders, &binder) ||
-					len(binder) == 0 {
-					return false
-				}
-				m.pskBinders = append(m.pskBinders, binder)
-			}
-		default:
-			// Ignore unknown extensions.
-			continue
-		}
-
-		if !extData.Empty() {
-			return false
-		}
-	}
-
-	return true
-}
-
-type serverHelloMsg struct {
-	raw                          []byte
-	vers                         uint16
-	random                       []byte
-	sessionId                    []byte
-	cipherSuite                  uint16
-	compressionMethod            uint8
-	ocspStapling                 bool
-	ticketSupported              bool
-	secureRenegotiationSupported bool
-	secureRenegotiation          []byte
-	alpnProtocol                 string
-	scts                         [][]byte
-	supportedVersion             uint16
-	serverShare                  keyShare
-	selectedIdentityPresent      bool
-	selectedIdentity             uint16
-	supportedPoints              []uint8
-
-	// HelloRetryRequest extensions
-	cookie        []byte
-	selectedGroup CurveID
-}
-
-func (m *serverHelloMsg) marshal() []byte {
-	if m.raw != nil {
-		return m.raw
-	}
-
-	var b cryptobyte.Builder
-	b.AddUint8(typeServerHello)
-	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
-		b.AddUint16(m.vers)
-		addBytesWithLength(b, m.random, 32)
-		b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
-			b.AddBytes(m.sessionId)
-		})
-		b.AddUint16(m.cipherSuite)
-		b.AddUint8(m.compressionMethod)
-
-		// If extensions aren't present, omit them.
-		var extensionsPresent bool
-		bWithoutExtensions := *b
-
-		b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-			if m.ocspStapling {
-				b.AddUint16(extensionStatusRequest)
-				b.AddUint16(0) // empty extension_data
-			}
-			if m.ticketSupported {
-				b.AddUint16(extensionSessionTicket)
-				b.AddUint16(0) // empty extension_data
-			}
-			if m.secureRenegotiationSupported {
-				b.AddUint16(extensionRenegotiationInfo)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
-						b.AddBytes(m.secureRenegotiation)
-					})
-				})
-			}
-			if len(m.alpnProtocol) > 0 {
-				b.AddUint16(extensionALPN)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-						b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
-							b.AddBytes([]byte(m.alpnProtocol))
-						})
-					})
-				})
-			}
-			if len(m.scts) > 0 {
-				b.AddUint16(extensionSCT)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-						for _, sct := range m.scts {
-							b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-								b.AddBytes(sct)
-							})
-						}
-					})
-				})
-			}
-			if m.supportedVersion != 0 {
-				b.AddUint16(extensionSupportedVersions)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint16(m.supportedVersion)
-				})
-			}
-			if m.serverShare.group != 0 {
-				b.AddUint16(extensionKeyShare)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint16(uint16(m.serverShare.group))
-					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-						b.AddBytes(m.serverShare.data)
-					})
-				})
-			}
-			if m.selectedIdentityPresent {
-				b.AddUint16(extensionPreSharedKey)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint16(m.selectedIdentity)
-				})
-			}
-
-			if len(m.cookie) > 0 {
-				b.AddUint16(extensionCookie)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-						b.AddBytes(m.cookie)
-					})
-				})
-			}
-			if m.selectedGroup != 0 {
-				b.AddUint16(extensionKeyShare)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint16(uint16(m.selectedGroup))
-				})
-			}
-			if len(m.supportedPoints) > 0 {
-				b.AddUint16(extensionSupportedPoints)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
-						b.AddBytes(m.supportedPoints)
-					})
-				})
-			}
-
-			extensionsPresent = len(b.BytesOrPanic()) > 2
-		})
-
-		if !extensionsPresent {
-			*b = bWithoutExtensions
-		}
-	})
-
-	m.raw = b.BytesOrPanic()
-	return m.raw
-}
-
-func (m *serverHelloMsg) unmarshal(data []byte) bool {
-	*m = serverHelloMsg{raw: data}
-	s := cryptobyte.String(data)
-
-	if !s.Skip(4) || // message type and uint24 length field
-		!s.ReadUint16(&m.vers) || !s.ReadBytes(&m.random, 32) ||
-		!readUint8LengthPrefixed(&s, &m.sessionId) ||
-		!s.ReadUint16(&m.cipherSuite) ||
-		!s.ReadUint8(&m.compressionMethod) {
-		return false
-	}
-
-	if s.Empty() {
-		// ServerHello is optionally followed by extension data
-		return true
-	}
-
-	var extensions cryptobyte.String
-	if !s.ReadUint16LengthPrefixed(&extensions) || !s.Empty() {
-		return false
-	}
-
-	for !extensions.Empty() {
-		var extension uint16
-		var extData cryptobyte.String
-		if !extensions.ReadUint16(&extension) ||
-			!extensions.ReadUint16LengthPrefixed(&extData) {
-			return false
-		}
-
-		switch extension {
-		case extensionStatusRequest:
-			m.ocspStapling = true
-		case extensionSessionTicket:
-			m.ticketSupported = true
-		case extensionRenegotiationInfo:
-			if !readUint8LengthPrefixed(&extData, &m.secureRenegotiation) {
-				return false
-			}
-			m.secureRenegotiationSupported = true
-		case extensionALPN:
-			var protoList cryptobyte.String
-			if !extData.ReadUint16LengthPrefixed(&protoList) || protoList.Empty() {
-				return false
-			}
-			var proto cryptobyte.String
-			if !protoList.ReadUint8LengthPrefixed(&proto) ||
-				proto.Empty() || !protoList.Empty() {
-				return false
-			}
-			m.alpnProtocol = string(proto)
-		case extensionSCT:
-			var sctList cryptobyte.String
-			if !extData.ReadUint16LengthPrefixed(&sctList) || sctList.Empty() {
-				return false
-			}
-			for !sctList.Empty() {
-				var sct []byte
-				if !readUint16LengthPrefixed(&sctList, &sct) ||
-					len(sct) == 0 {
-					return false
-				}
-				m.scts = append(m.scts, sct)
-			}
-		case extensionSupportedVersions:
-			if !extData.ReadUint16(&m.supportedVersion) {
-				return false
-			}
-		case extensionCookie:
-			if !readUint16LengthPrefixed(&extData, &m.cookie) ||
-				len(m.cookie) == 0 {
-				return false
-			}
-		case extensionKeyShare:
-			// This extension has different formats in SH and HRR, accept either
-			// and let the handshake logic decide. See RFC 8446, Section 4.2.8.
-			if len(extData) == 2 {
-				if !extData.ReadUint16((*uint16)(&m.selectedGroup)) {
-					return false
-				}
-			} else {
-				if !extData.ReadUint16((*uint16)(&m.serverShare.group)) ||
-					!readUint16LengthPrefixed(&extData, &m.serverShare.data) {
-					return false
-				}
-			}
-		case extensionPreSharedKey:
-			m.selectedIdentityPresent = true
-			if !extData.ReadUint16(&m.selectedIdentity) {
-				return false
-			}
-		case extensionSupportedPoints:
-			// RFC 4492, Section 5.1.2
-			if !readUint8LengthPrefixed(&extData, &m.supportedPoints) ||
-				len(m.supportedPoints) == 0 {
-				return false
-			}
-		default:
-			// Ignore unknown extensions.
-			continue
-		}
-
-		if !extData.Empty() {
-			return false
-		}
-	}
-
-	return true
-}
-
-type encryptedExtensionsMsg struct {
-	raw          []byte
-	alpnProtocol string
-}
-
-func (m *encryptedExtensionsMsg) marshal() []byte {
-	if m.raw != nil {
-		return m.raw
-	}
-
-	var b cryptobyte.Builder
-	b.AddUint8(typeEncryptedExtensions)
-	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
-		b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-			if len(m.alpnProtocol) > 0 {
-				b.AddUint16(extensionALPN)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-						b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
-							b.AddBytes([]byte(m.alpnProtocol))
-						})
-					})
-				})
-			}
-		})
-	})
-
-	m.raw = b.BytesOrPanic()
-	return m.raw
-}
-
-func (m *encryptedExtensionsMsg) unmarshal(data []byte) bool {
-	*m = encryptedExtensionsMsg{raw: data}
-	s := cryptobyte.String(data)
-
-	var extensions cryptobyte.String
-	if !s.Skip(4) || // message type and uint24 length field
-		!s.ReadUint16LengthPrefixed(&extensions) || !s.Empty() {
-		return false
-	}
-
-	for !extensions.Empty() {
-		var extension uint16
-		var extData cryptobyte.String
-		if !extensions.ReadUint16(&extension) ||
-			!extensions.ReadUint16LengthPrefixed(&extData) {
-			return false
-		}
-
-		switch extension {
-		case extensionALPN:
-			var protoList cryptobyte.String
-			if !extData.ReadUint16LengthPrefixed(&protoList) || protoList.Empty() {
-				return false
-			}
-			var proto cryptobyte.String
-			if !protoList.ReadUint8LengthPrefixed(&proto) ||
-				proto.Empty() || !protoList.Empty() {
-				return false
-			}
-			m.alpnProtocol = string(proto)
-		default:
-			// Ignore unknown extensions.
-			continue
-		}
-
-		if !extData.Empty() {
-			return false
-		}
-	}
-
-	return true
-}
-
-type endOfEarlyDataMsg struct{}
-
-func (m *endOfEarlyDataMsg) marshal() []byte {
-	x := make([]byte, 4)
-	x[0] = typeEndOfEarlyData
-	return x
-}
-
-func (m *endOfEarlyDataMsg) unmarshal(data []byte) bool {
-	return len(data) == 4
-}
-
-type keyUpdateMsg struct {
-	raw             []byte
-	updateRequested bool
-}
-
-func (m *keyUpdateMsg) marshal() []byte {
-	if m.raw != nil {
-		return m.raw
-	}
-
-	var b cryptobyte.Builder
-	b.AddUint8(typeKeyUpdate)
-	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
-		if m.updateRequested {
-			b.AddUint8(1)
-		} else {
-			b.AddUint8(0)
-		}
-	})
-
-	m.raw = b.BytesOrPanic()
-	return m.raw
-}
-
-func (m *keyUpdateMsg) unmarshal(data []byte) bool {
-	m.raw = data
-	s := cryptobyte.String(data)
-
-	var updateRequested uint8
-	if !s.Skip(4) || // message type and uint24 length field
-		!s.ReadUint8(&updateRequested) || !s.Empty() {
-		return false
-	}
-	switch updateRequested {
-	case 0:
-		m.updateRequested = false
-	case 1:
-		m.updateRequested = true
-	default:
-		return false
-	}
-	return true
-}
-
-type newSessionTicketMsgTLS13 struct {
-	raw          []byte
-	lifetime     uint32
-	ageAdd       uint32
-	nonce        []byte
-	label        []byte
-	maxEarlyData uint32
-}
-
-func (m *newSessionTicketMsgTLS13) marshal() []byte {
-	if m.raw != nil {
-		return m.raw
-	}
-
-	var b cryptobyte.Builder
-	b.AddUint8(typeNewSessionTicket)
-	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
-		b.AddUint32(m.lifetime)
-		b.AddUint32(m.ageAdd)
-		b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
-			b.AddBytes(m.nonce)
-		})
-		b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-			b.AddBytes(m.label)
-		})
-
-		b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-			if m.maxEarlyData > 0 {
-				b.AddUint16(extensionEarlyData)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint32(m.maxEarlyData)
-				})
-			}
-		})
-	})
-
-	m.raw = b.BytesOrPanic()
-	return m.raw
-}
-
-func (m *newSessionTicketMsgTLS13) unmarshal(data []byte) bool {
-	*m = newSessionTicketMsgTLS13{raw: data}
-	s := cryptobyte.String(data)
-
-	var extensions cryptobyte.String
-	if !s.Skip(4) || // message type and uint24 length field
-		!s.ReadUint32(&m.lifetime) ||
-		!s.ReadUint32(&m.ageAdd) ||
-		!readUint8LengthPrefixed(&s, &m.nonce) ||
-		!readUint16LengthPrefixed(&s, &m.label) ||
-		!s.ReadUint16LengthPrefixed(&extensions) ||
-		!s.Empty() {
-		return false
-	}
-
-	for !extensions.Empty() {
-		var extension uint16
-		var extData cryptobyte.String
-		if !extensions.ReadUint16(&extension) ||
-			!extensions.ReadUint16LengthPrefixed(&extData) {
-			return false
-		}
-
-		switch extension {
-		case extensionEarlyData:
-			if !extData.ReadUint32(&m.maxEarlyData) {
-				return false
-			}
-		default:
-			// Ignore unknown extensions.
-			continue
-		}
-
-		if !extData.Empty() {
-			return false
-		}
-	}
-
-	return true
-}
-
-type certificateRequestMsgTLS13 struct {
-	raw                              []byte
-	ocspStapling                     bool
-	scts                             bool
-	supportedSignatureAlgorithms     []SignatureScheme
-	supportedSignatureAlgorithmsCert []SignatureScheme
-	certificateAuthorities           [][]byte
-}
-
-func (m *certificateRequestMsgTLS13) marshal() []byte {
-	if m.raw != nil {
-		return m.raw
-	}
-
-	var b cryptobyte.Builder
-	b.AddUint8(typeCertificateRequest)
-	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
-		// certificate_request_context (SHALL be zero length unless used for
-		// post-handshake authentication)
-		b.AddUint8(0)
-
-		b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-			if m.ocspStapling {
-				b.AddUint16(extensionStatusRequest)
-				b.AddUint16(0) // empty extension_data
-			}
-			if m.scts {
-				// RFC 8446, Section 4.4.2.1 makes no mention of
-				// signed_certificate_timestamp in CertificateRequest, but
-				// "Extensions in the Certificate message from the client MUST
-				// correspond to extensions in the CertificateRequest message
-				// from the server." and it appears in the table in Section 4.2.
-				b.AddUint16(extensionSCT)
-				b.AddUint16(0) // empty extension_data
-			}
-			if len(m.supportedSignatureAlgorithms) > 0 {
-				b.AddUint16(extensionSignatureAlgorithms)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-						for _, sigAlgo := range m.supportedSignatureAlgorithms {
-							b.AddUint16(uint16(sigAlgo))
-						}
-					})
-				})
-			}
-			if len(m.supportedSignatureAlgorithmsCert) > 0 {
-				b.AddUint16(extensionSignatureAlgorithmsCert)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-						for _, sigAlgo := range m.supportedSignatureAlgorithmsCert {
-							b.AddUint16(uint16(sigAlgo))
-						}
-					})
-				})
-			}
-			if len(m.certificateAuthorities) > 0 {
-				b.AddUint16(extensionCertificateAuthorities)
-				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-						for _, ca := range m.certificateAuthorities {
-							b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-								b.AddBytes(ca)
-							})
-						}
-					})
-				})
-			}
-		})
-	})
-
-	m.raw = b.BytesOrPanic()
-	return m.raw
-}
-
-func (m *certificateRequestMsgTLS13) unmarshal(data []byte) bool {
-	*m = certificateRequestMsgTLS13{raw: data}
-	s := cryptobyte.String(data)
-
-	var context, extensions cryptobyte.String
-	if !s.Skip(4) || // message type and uint24 length field
-		!s.ReadUint8LengthPrefixed(&context) || !context.Empty() ||
-		!s.ReadUint16LengthPrefixed(&extensions) ||
-		!s.Empty() {
-		return false
-	}
-
-	for !extensions.Empty() {
-		var extension uint16
-		var extData cryptobyte.String
-		if !extensions.ReadUint16(&extension) ||
-			!extensions.ReadUint16LengthPrefixed(&extData) {
-			return false
-		}
-
-		switch extension {
-		case extensionStatusRequest:
-			m.ocspStapling = true
-		case extensionSCT:
-			m.scts = true
-		case extensionSignatureAlgorithms:
-			var sigAndAlgs cryptobyte.String
-			if !extData.ReadUint16LengthPrefixed(&sigAndAlgs) || sigAndAlgs.Empty() {
-				return false
-			}
-			for !sigAndAlgs.Empty() {
-				var sigAndAlg uint16
-				if !sigAndAlgs.ReadUint16(&sigAndAlg) {
-					return false
-				}
-				m.supportedSignatureAlgorithms = append(
-					m.supportedSignatureAlgorithms, SignatureScheme(sigAndAlg))
-			}
-		case extensionSignatureAlgorithmsCert:
-			var sigAndAlgs cryptobyte.String
-			if !extData.ReadUint16LengthPrefixed(&sigAndAlgs) || sigAndAlgs.Empty() {
-				return false
-			}
-			for !sigAndAlgs.Empty() {
-				var sigAndAlg uint16
-				if !sigAndAlgs.ReadUint16(&sigAndAlg) {
-					return false
-				}
-				m.supportedSignatureAlgorithmsCert = append(
-					m.supportedSignatureAlgorithmsCert, SignatureScheme(sigAndAlg))
-			}
-		case extensionCertificateAuthorities:
-			var auths cryptobyte.String
-			if !extData.ReadUint16LengthPrefixed(&auths) || auths.Empty() {
-				return false
-			}
-			for !auths.Empty() {
-				var ca []byte
-				if !readUint16LengthPrefixed(&auths, &ca) || len(ca) == 0 {
-					return false
-				}
-				m.certificateAuthorities = append(m.certificateAuthorities, ca)
-			}
-		default:
-			// Ignore unknown extensions.
-			continue
-		}
-
-		if !extData.Empty() {
-			return false
-		}
-	}
-
-	return true
-}
-
-type certificateMsg struct {
-	raw          []byte
-	certificates [][]byte
-}
-
-func (m *certificateMsg) marshal() (x []byte) {
-	if m.raw != nil {
-		return m.raw
-	}
-
-	var i int
-	for _, slice := range m.certificates {
-		i += len(slice)
-	}
-
-	length := 3 + 3*len(m.certificates) + i
-	x = make([]byte, 4+length)
-	x[0] = typeCertificate
-	x[1] = uint8(length >> 16)
-	x[2] = uint8(length >> 8)
-	x[3] = uint8(length)
-
-	certificateOctets := length - 3
-	x[4] = uint8(certificateOctets >> 16)
-	x[5] = uint8(certificateOctets >> 8)
-	x[6] = uint8(certificateOctets)
-
-	y := x[7:]
-	for _, slice := range m.certificates {
-		y[0] = uint8(len(slice) >> 16)
-		y[1] = uint8(len(slice) >> 8)
-		y[2] = uint8(len(slice))
-		copy(y[3:], slice)
-		y = y[3+len(slice):]
-	}
-
-	m.raw = x
-	return
-}
-
-func (m *certificateMsg) unmarshal(data []byte) bool {
-	if len(data) < 7 {
-		return false
-	}
-
-	m.raw = data
-	certsLen := uint32(data[4])<<16 | uint32(data[5])<<8 | uint32(data[6])
-	if uint32(len(data)) != certsLen+7 {
-		return false
-	}
-
-	numCerts := 0
-	d := data[7:]
-	for certsLen > 0 {
-		if len(d) < 4 {
-			return false
-		}
-		certLen := uint32(d[0])<<16 | uint32(d[1])<<8 | uint32(d[2])
-		if uint32(len(d)) < 3+certLen {
-			return false
-		}
-		d = d[3+certLen:]
-		certsLen -= 3 + certLen
-		numCerts++
-	}
-
-	m.certificates = make([][]byte, numCerts)
-	d = data[7:]
-	for i := 0; i < numCerts; i++ {
-		certLen := uint32(d[0])<<16 | uint32(d[1])<<8 | uint32(d[2])
-		m.certificates[i] = d[3 : 3+certLen]
-		d = d[3+certLen:]
-	}
-
-	return true
-}
-
-type certificateMsgTLS13 struct {
-	raw          []byte
-	certificate  Certificate
-	ocspStapling bool
-	scts         bool
-}
-
-func (m *certificateMsgTLS13) marshal() []byte {
-	if m.raw != nil {
-		return m.raw
-	}
-
-	var b cryptobyte.Builder
-	b.AddUint8(typeCertificate)
-	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
-		b.AddUint8(0) // certificate_request_context
-
-		certificate := m.certificate
-		if !m.ocspStapling {
-			certificate.OCSPStaple = nil
-		}
-		if !m.scts {
-			certificate.SignedCertificateTimestamps = nil
-		}
-		marshalCertificate(b, certificate)
-	})
-
-	m.raw = b.BytesOrPanic()
-	return m.raw
-}
-
-func marshalCertificate(b *cryptobyte.Builder, certificate Certificate) {
-	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
-		for i, cert := range certificate.Certificate {
-			b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
-				b.AddBytes(cert)
-			})
-			b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-				if i > 0 {
-					// This library only supports OCSP and SCT for leaf certificates.
-					return
-				}
-				if certificate.OCSPStaple != nil {
-					b.AddUint16(extensionStatusRequest)
-					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-						b.AddUint8(statusTypeOCSP)
-						b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
-							b.AddBytes(certificate.OCSPStaple)
-						})
-					})
-				}
-				if certificate.SignedCertificateTimestamps != nil {
-					b.AddUint16(extensionSCT)
-					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-						b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-							for _, sct := range certificate.SignedCertificateTimestamps {
-								b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-									b.AddBytes(sct)
-								})
-							}
-						})
-					})
-				}
-			})
-		}
-	})
-}
-
-func (m *certificateMsgTLS13) unmarshal(data []byte) bool {
-	*m = certificateMsgTLS13{raw: data}
-	s := cryptobyte.String(data)
-
-	var context cryptobyte.String
-	if !s.Skip(4) || // message type and uint24 length field
-		!s.ReadUint8LengthPrefixed(&context) || !context.Empty() ||
-		!unmarshalCertificate(&s, &m.certificate) ||
-		!s.Empty() {
-		return false
-	}
-
-	m.scts = m.certificate.SignedCertificateTimestamps != nil
-	m.ocspStapling = m.certificate.OCSPStaple != nil
-
-	return true
-}
-
-func unmarshalCertificate(s *cryptobyte.String, certificate *Certificate) bool {
-	var certList cryptobyte.String
-	if !s.ReadUint24LengthPrefixed(&certList) {
-		return false
-	}
-	for !certList.Empty() {
-		var cert []byte
-		var extensions cryptobyte.String
-		if !readUint24LengthPrefixed(&certList, &cert) ||
-			!certList.ReadUint16LengthPrefixed(&extensions) {
-			return false
-		}
-		certificate.Certificate = append(certificate.Certificate, cert)
-		for !extensions.Empty() {
-			var extension uint16
-			var extData cryptobyte.String
-			if !extensions.ReadUint16(&extension) ||
-				!extensions.ReadUint16LengthPrefixed(&extData) {
-				return false
-			}
-			if len(certificate.Certificate) > 1 {
-				// This library only supports OCSP and SCT for leaf certificates.
-				continue
-			}
-
-			switch extension {
-			case extensionStatusRequest:
-				var statusType uint8
-				if !extData.ReadUint8(&statusType) || statusType != statusTypeOCSP ||
-					!readUint24LengthPrefixed(&extData, &certificate.OCSPStaple) ||
-					len(certificate.OCSPStaple) == 0 {
-					return false
-				}
-			case extensionSCT:
-				var sctList cryptobyte.String
-				if !extData.ReadUint16LengthPrefixed(&sctList) || sctList.Empty() {
-					return false
-				}
-				for !sctList.Empty() {
-					var sct []byte
-					if !readUint16LengthPrefixed(&sctList, &sct) ||
-						len(sct) == 0 {
-						return false
-					}
-					certificate.SignedCertificateTimestamps = append(
-						certificate.SignedCertificateTimestamps, sct)
-				}
-			default:
-				// Ignore unknown extensions.
-				continue
-			}
-
-			if !extData.Empty() {
-				return false
-			}
-		}
-	}
-	return true
-}
-
-type serverKeyExchangeMsg struct {
-	raw []byte
-	key []byte
-}
-
-func (m *serverKeyExchangeMsg) marshal() []byte {
-	if m.raw != nil {
-		return m.raw
-	}
-	length := len(m.key)
-	x := make([]byte, length+4)
-	x[0] = typeServerKeyExchange
-	x[1] = uint8(length >> 16)
-	x[2] = uint8(length >> 8)
-	x[3] = uint8(length)
-	copy(x[4:], m.key)
-
-	m.raw = x
-	return x
-}
-
-func (m *serverKeyExchangeMsg) unmarshal(data []byte) bool {
-	m.raw = data
-	if len(data) < 4 {
-		return false
-	}
-	m.key = data[4:]
-	return true
-}
-
-type certificateStatusMsg struct {
-	raw      []byte
-	response []byte
-}
-
-func (m *certificateStatusMsg) marshal() []byte {
-	if m.raw != nil {
-		return m.raw
-	}
-
-	var b cryptobyte.Builder
-	b.AddUint8(typeCertificateStatus)
-	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
-		b.AddUint8(statusTypeOCSP)
-		b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
-			b.AddBytes(m.response)
-		})
-	})
-
-	m.raw = b.BytesOrPanic()
-	return m.raw
-}
-
-func (m *certificateStatusMsg) unmarshal(data []byte) bool {
-	m.raw = data
-	s := cryptobyte.String(data)
-
-	var statusType uint8
-	if !s.Skip(4) || // message type and uint24 length field
-		!s.ReadUint8(&statusType) || statusType != statusTypeOCSP ||
-		!readUint24LengthPrefixed(&s, &m.response) ||
-		len(m.response) == 0 || !s.Empty() {
-		return false
-	}
-	return true
-}
-
-type serverHelloDoneMsg struct{}
-
-func (m *serverHelloDoneMsg) marshal() []byte {
-	x := make([]byte, 4)
-	x[0] = typeServerHelloDone
-	return x
-}
-
-func (m *serverHelloDoneMsg) unmarshal(data []byte) bool {
-	return len(data) == 4
-}
-
-type clientKeyExchangeMsg struct {
-	raw        []byte
-	ciphertext []byte
-}
-
-func (m *clientKeyExchangeMsg) marshal() []byte {
-	if m.raw != nil {
-		return m.raw
-	}
-	length := len(m.ciphertext)
-	x := make([]byte, length+4)
-	x[0] = typeClientKeyExchange
-	x[1] = uint8(length >> 16)
-	x[2] = uint8(length >> 8)
-	x[3] = uint8(length)
-	copy(x[4:], m.ciphertext)
-
-	m.raw = x
-	return x
-}
-
-func (m *clientKeyExchangeMsg) unmarshal(data []byte) bool {
-	m.raw = data
-	if len(data) < 4 {
-		return false
-	}
-	l := int(data[1])<<16 | int(data[2])<<8 | int(data[3])
-	if l != len(data)-4 {
-		return false
-	}
-	m.ciphertext = data[4:]
-	return true
-}
-
-type finishedMsg struct {
-	raw        []byte
-	verifyData []byte
-}
-
-func (m *finishedMsg) marshal() []byte {
-	if m.raw != nil {
-		return m.raw
-	}
-
-	var b cryptobyte.Builder
-	b.AddUint8(typeFinished)
-	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
-		b.AddBytes(m.verifyData)
-	})
-
-	m.raw = b.BytesOrPanic()
-	return m.raw
-}
-
-func (m *finishedMsg) unmarshal(data []byte) bool {
-	m.raw = data
-	s := cryptobyte.String(data)
-	return s.Skip(1) &&
-		readUint24LengthPrefixed(&s, &m.verifyData) &&
-		s.Empty()
-}
-
-type certificateRequestMsg struct {
-	raw []byte
-	// hasSignatureAlgorithm indicates whether this message includes a list of
-	// supported signature algorithms. This change was introduced with TLS 1.2.
-	hasSignatureAlgorithm bool
-
-	certificateTypes             []byte
-	supportedSignatureAlgorithms []SignatureScheme
-	certificateAuthorities       [][]byte
-}
-
-func (m *certificateRequestMsg) marshal() (x []byte) {
-	if m.raw != nil {
-		return m.raw
-	}
-
-	// See RFC 4346, Section 7.4.4.
-	length := 1 + len(m.certificateTypes) + 2
-	casLength := 0
-	for _, ca := range m.certificateAuthorities {
-		casLength += 2 + len(ca)
-	}
-	length += casLength
-
-	if m.hasSignatureAlgorithm {
-		length += 2 + 2*len(m.supportedSignatureAlgorithms)
-	}
-
-	x = make([]byte, 4+length)
-	x[0] = typeCertificateRequest
-	x[1] = uint8(length >> 16)
-	x[2] = uint8(length >> 8)
-	x[3] = uint8(length)
-
-	x[4] = uint8(len(m.certificateTypes))
-
-	copy(x[5:], m.certificateTypes)
-	y := x[5+len(m.certificateTypes):]
-
-	if m.hasSignatureAlgorithm {
-		n := len(m.supportedSignatureAlgorithms) * 2
-		y[0] = uint8(n >> 8)
-		y[1] = uint8(n)
-		y = y[2:]
-		for _, sigAlgo := range m.supportedSignatureAlgorithms {
-			y[0] = uint8(sigAlgo >> 8)
-			y[1] = uint8(sigAlgo)
-			y = y[2:]
-		}
-	}
-
-	y[0] = uint8(casLength >> 8)
-	y[1] = uint8(casLength)
-	y = y[2:]
-	for _, ca := range m.certificateAuthorities {
-		y[0] = uint8(len(ca) >> 8)
-		y[1] = uint8(len(ca))
-		y = y[2:]
-		copy(y, ca)
-		y = y[len(ca):]
-	}
-
-	m.raw = x
-	return
-}
-
-func (m *certificateRequestMsg) unmarshal(data []byte) bool {
-	m.raw = data
-
-	if len(data) < 5 {
-		return false
-	}
-
-	length := uint32(data[1])<<16 | uint32(data[2])<<8 | uint32(data[3])
-	if uint32(len(data))-4 != length {
-		return false
-	}
-
-	numCertTypes := int(data[4])
-	data = data[5:]
-	if numCertTypes == 0 || len(data) <= numCertTypes {
-		return false
-	}
-
-	m.certificateTypes = make([]byte, numCertTypes)
-	if copy(m.certificateTypes, data) != numCertTypes {
-		return false
-	}
-
-	data = data[numCertTypes:]
-
-	if m.hasSignatureAlgorithm {
-		if len(data) < 2 {
-			return false
-		}
-		sigAndHashLen := uint16(data[0])<<8 | uint16(data[1])
-		data = data[2:]
-		if sigAndHashLen&1 != 0 {
-			return false
-		}
-		if len(data) < int(sigAndHashLen) {
-			return false
-		}
-		numSigAlgos := sigAndHashLen / 2
-		m.supportedSignatureAlgorithms = make([]SignatureScheme, numSigAlgos)
-		for i := range m.supportedSignatureAlgorithms {
-			m.supportedSignatureAlgorithms[i] = SignatureScheme(data[0])<<8 | SignatureScheme(data[1])
-			data = data[2:]
-		}
-	}
-
-	if len(data) < 2 {
-		return false
-	}
-	casLength := uint16(data[0])<<8 | uint16(data[1])
-	data = data[2:]
-	if len(data) < int(casLength) {
-		return false
-	}
-	cas := make([]byte, casLength)
-	copy(cas, data)
-	data = data[casLength:]
-
-	m.certificateAuthorities = nil
-	for len(cas) > 0 {
-		if len(cas) < 2 {
-			return false
-		}
-		caLen := uint16(cas[0])<<8 | uint16(cas[1])
-		cas = cas[2:]
-
-		if len(cas) < int(caLen) {
-			return false
-		}
-
-		m.certificateAuthorities = append(m.certificateAuthorities, cas[:caLen])
-		cas = cas[caLen:]
-	}
-
-	return len(data) == 0
-}
-
-type certificateVerifyMsg struct {
-	raw                   []byte
-	hasSignatureAlgorithm bool // format change introduced in TLS 1.2
-	signatureAlgorithm    SignatureScheme
-	signature             []byte
-}
-
-func (m *certificateVerifyMsg) marshal() (x []byte) {
-	if m.raw != nil {
-		return m.raw
-	}
-
-	var b cryptobyte.Builder
-	b.AddUint8(typeCertificateVerify)
-	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
-		if m.hasSignatureAlgorithm {
-			b.AddUint16(uint16(m.signatureAlgorithm))
-		}
-		b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
-			b.AddBytes(m.signature)
-		})
-	})
-
-	m.raw = b.BytesOrPanic()
-	return m.raw
-}
-
-func (m *certificateVerifyMsg) unmarshal(data []byte) bool {
-	m.raw = data
-	s := cryptobyte.String(data)
-
-	if !s.Skip(4) { // message type and uint24 length field
-		return false
-	}
-	if m.hasSignatureAlgorithm {
-		if !s.ReadUint16((*uint16)(&m.signatureAlgorithm)) {
-			return false
-		}
-	}
-	return readUint16LengthPrefixed(&s, &m.signature) && s.Empty()
-}
-
-type newSessionTicketMsg struct {
-	raw    []byte
-	ticket []byte
-}
-
-func (m *newSessionTicketMsg) marshal() (x []byte) {
-	if m.raw != nil {
-		return m.raw
-	}
-
-	// See RFC 5077, Section 3.3.
-	ticketLen := len(m.ticket)
-	length := 2 + 4 + ticketLen
-	x = make([]byte, 4+length)
-	x[0] = typeNewSessionTicket
-	x[1] = uint8(length >> 16)
-	x[2] = uint8(length >> 8)
-	x[3] = uint8(length)
-	x[8] = uint8(ticketLen >> 8)
-	x[9] = uint8(ticketLen)
-	copy(x[10:], m.ticket)
-
-	m.raw = x
-
-	return
-}
-
-func (m *newSessionTicketMsg) unmarshal(data []byte) bool {
-	m.raw = data
-
-	if len(data) < 10 {
-		return false
-	}
-
-	length := uint32(data[1])<<16 | uint32(data[2])<<8 | uint32(data[3])
-	if uint32(len(data))-4 != length {
-		return false
-	}
-
-	ticketLen := int(data[8])<<8 + int(data[9])
-	if len(data)-10 != ticketLen {
-		return false
-	}
-
-	m.ticket = data[10:]
-
-	return true
-}
-
-type helloRequestMsg struct {
-}
-
-func (*helloRequestMsg) marshal() []byte {
-	return []byte{typeHelloRequest, 0, 0, 0}
-}
-
-func (*helloRequestMsg) unmarshal(data []byte) bool {
-	return len(data) == 4
-}
diff --git a/contrib/go/_std_1.18/src/crypto/tls/handshake_server.go b/contrib/go/_std_1.18/src/crypto/tls/handshake_server.go
deleted file mode 100644
index 097046340b..0000000000
--- a/contrib/go/_std_1.18/src/crypto/tls/handshake_server.go
+++ /dev/null
@@ -1,875 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package tls
-
-import (
-	"context"
-	"crypto"
-	"crypto/ecdsa"
-	"crypto/ed25519"
-	"crypto/rsa"
-	"crypto/subtle"
-	"crypto/x509"
-	"errors"
-	"fmt"
-	"hash"
-	"io"
-	"sync/atomic"
-	"time"
-)
-
-// serverHandshakeState contains details of a server handshake in progress.
-// It's discarded once the handshake has completed.
-type serverHandshakeState struct {
-	c            *Conn
-	ctx          context.Context
-	clientHello  *clientHelloMsg
-	hello        *serverHelloMsg
-	suite        *cipherSuite
-	ecdheOk      bool
-	ecSignOk     bool
-	rsaDecryptOk bool
-	rsaSignOk    bool
-	sessionState *sessionState
-	finishedHash finishedHash
-	masterSecret []byte
-	cert         *Certificate
-}
-
-// serverHandshake performs a TLS handshake as a server.
-func (c *Conn) serverHandshake(ctx context.Context) error {
-	clientHello, err := c.readClientHello(ctx)
-	if err != nil {
-		return err
-	}
-
-	if c.vers == VersionTLS13 {
-		hs := serverHandshakeStateTLS13{
-			c:           c,
-			ctx:         ctx,
-			clientHello: clientHello,
-		}
-		return hs.handshake()
-	}
-
-	hs := serverHandshakeState{
-		c:           c,
-		ctx:         ctx,
-		clientHello: clientHello,
-	}
-	return hs.handshake()
-}
-
-func (hs *serverHandshakeState) handshake() error {
-	c := hs.c
-
-	if err := hs.processClientHello(); err != nil {
-		return err
-	}
-
-	// For an overview of TLS handshaking, see RFC 5246, Section 7.3.
-	c.buffering = true
-	if hs.checkForResumption() {
-		// The client has included a session ticket and so we do an abbreviated handshake.
-		c.didResume = true
-		if err := hs.doResumeHandshake(); err != nil {
-			return err
-		}
-		if err := hs.establishKeys(); err != nil {
-			return err
-		}
-		if err := hs.sendSessionTicket(); err != nil {
-			return err
-		}
-		if err := hs.sendFinished(c.serverFinished[:]); err != nil {
-			return err
-		}
-		if _, err := c.flush(); err != nil {
-			return err
-		}
-		c.clientFinishedIsFirst = false
-		if err := hs.readFinished(nil); err != nil {
-			return err
-		}
-	} else {
-		// The client didn't include a session ticket, or it wasn't
-		// valid so we do a full handshake.
-		if err := hs.pickCipherSuite(); err != nil {
-			return err
-		}
-		if err := hs.doFullHandshake(); err != nil {
-			return err
-		}
-		if err := hs.establishKeys(); err != nil {
-			return err
-		}
-		if err := hs.readFinished(c.clientFinished[:]); err != nil {
-			return err
-		}
-		c.clientFinishedIsFirst = true
-		c.buffering = true
-		if err := hs.sendSessionTicket(); err != nil {
-			return err
-		}
-		if err := hs.sendFinished(nil); err != nil {
-			return err
-		}
-		if _, err := c.flush(); err != nil {
-			return err
-		}
-	}
-
-	c.ekm = ekmFromMasterSecret(c.vers, hs.suite, hs.masterSecret, hs.clientHello.random, hs.hello.random)
-	atomic.StoreUint32(&c.handshakeStatus, 1)
-
-	return nil
-}
-
-// readClientHello reads a ClientHello message and selects the protocol version.
-func (c *Conn) readClientHello(ctx context.Context) (*clientHelloMsg, error) {
-	msg, err := c.readHandshake()
-	if err != nil {
-		return nil, err
-	}
-	clientHello, ok := msg.(*clientHelloMsg)
-	if !ok {
-		c.sendAlert(alertUnexpectedMessage)
-		return nil, unexpectedMessageError(clientHello, msg)
-	}
-
-	var configForClient *Config
-	originalConfig := c.config
-	if c.config.GetConfigForClient != nil {
-		chi := clientHelloInfo(ctx, c, clientHello)
-		if configForClient, err = c.config.GetConfigForClient(chi); err != nil {
-			c.sendAlert(alertInternalError)
-			return nil, err
-		} else if configForClient != nil {
-			c.config = configForClient
-		}
-	}
-	c.ticketKeys = originalConfig.ticketKeys(configForClient)
-
-	clientVersions := clientHello.supportedVersions
-	if len(clientHello.supportedVersions) == 0 {
-		clientVersions = supportedVersionsFromMax(clientHello.vers)
-	}
-	c.vers, ok = c.config.mutualVersion(roleServer, clientVersions)
-	if !ok {
-		c.sendAlert(alertProtocolVersion)
-		return nil, fmt.Errorf("tls: client offered only unsupported versions: %x", clientVersions)
-	}
-	c.haveVers = true
-	c.in.version = c.vers
-	c.out.version = c.vers
-
-	return clientHello, nil
-}
-
-func (hs *serverHandshakeState) processClientHello() error {
-	c := hs.c
-
-	hs.hello = new(serverHelloMsg)
-	hs.hello.vers = c.vers
-
-	foundCompression := false
-	// We only support null compression, so check that the client offered it.
-	for _, compression := range hs.clientHello.compressionMethods {
-		if compression == compressionNone {
-			foundCompression = true
-			break
-		}
-	}
-
-	if !foundCompression {
-		c.sendAlert(alertHandshakeFailure)
-		return errors.New("tls: client does not support uncompressed connections")
-	}
-
-	hs.hello.random = make([]byte, 32)
-	serverRandom := hs.hello.random
-	// Downgrade protection canaries. See RFC 8446, Section 4.1.3.
-	maxVers := c.config.maxSupportedVersion(roleServer)
-	if maxVers >= VersionTLS12 && c.vers < maxVers || testingOnlyForceDowngradeCanary {
-		if c.vers == VersionTLS12 {
-			copy(serverRandom[24:], downgradeCanaryTLS12)
-		} else {
-			copy(serverRandom[24:], downgradeCanaryTLS11)
-		}
-		serverRandom = serverRandom[:24]
-	}
-	_, err := io.ReadFull(c.config.rand(), serverRandom)
-	if err != nil {
-		c.sendAlert(alertInternalError)
-		return err
-	}
-
-	if len(hs.clientHello.secureRenegotiation) != 0 {
-		c.sendAlert(alertHandshakeFailure)
-		return errors.New("tls: initial handshake had non-empty renegotiation extension")
-	}
-
-	hs.hello.secureRenegotiationSupported = hs.clientHello.secureRenegotiationSupported
-	hs.hello.compressionMethod = compressionNone
-	if len(hs.clientHello.serverName) > 0 {
-		c.serverName = hs.clientHello.serverName
-	}
-
-	selectedProto, err := negotiateALPN(c.config.NextProtos, hs.clientHello.alpnProtocols)
-	if err != nil {
-		c.sendAlert(alertNoApplicationProtocol)
-		return err
-	}
-	hs.hello.alpnProtocol = selectedProto
-	c.clientProtocol = selectedProto
-
-	hs.cert, err = c.config.getCertificate(clientHelloInfo(hs.ctx, c, hs.clientHello))
-	if err != nil {
-		if err == errNoCertificates {
-			c.sendAlert(alertUnrecognizedName)
-		} else {
-			c.sendAlert(alertInternalError)
-		}
-		return err
-	}
-	if hs.clientHello.scts {
-		hs.hello.scts = hs.cert.SignedCertificateTimestamps
-	}
-
-	hs.ecdheOk = supportsECDHE(c.config, hs.clientHello.supportedCurves, hs.clientHello.supportedPoints)
-
-	if hs.ecdheOk {
-		// Although omitting the ec_point_formats extension is permitted, some
-		// old OpenSSL version will refuse to handshake if not present.
-		//
-		// Per RFC 4492, section 5.1.2, implementations MUST support the
-		// uncompressed point format. See golang.org/issue/31943.
-		hs.hello.supportedPoints = []uint8{pointFormatUncompressed}
-	}
-
-	if priv, ok := hs.cert.PrivateKey.(crypto.Signer); ok {
-		switch priv.Public().(type) {
-		case *ecdsa.PublicKey:
-			hs.ecSignOk = true
-		case ed25519.PublicKey:
-			hs.ecSignOk = true
-		case *rsa.PublicKey:
-			hs.rsaSignOk = true
-		default:
-			c.sendAlert(alertInternalError)
-			return fmt.Errorf("tls: unsupported signing key type (%T)", priv.Public())
-		}
-	}
-	if priv, ok := hs.cert.PrivateKey.(crypto.Decrypter); ok {
-		switch priv.Public().(type) {
-		case *rsa.PublicKey:
-			hs.rsaDecryptOk = true
-		default:
-			c.sendAlert(alertInternalError)
-			return fmt.Errorf("tls: unsupported decryption key type (%T)", priv.Public())
-		}
-	}
-
-	return nil
-}
-
-// negotiateALPN picks a shared ALPN protocol that both sides support in server
-// preference order. If ALPN is not configured or the peer doesn't support it,
-// it returns "" and no error.
-func negotiateALPN(serverProtos, clientProtos []string) (string, error) {
-	if len(serverProtos) == 0 || len(clientProtos) == 0 {
-		return "", nil
-	}
-	var http11fallback bool
-	for _, s := range serverProtos {
-		for _, c := range clientProtos {
-			if s == c {
-				return s, nil
-			}
-			if s == "h2" && c == "http/1.1" {
-				http11fallback = true
-			}
-		}
-	}
-	// As a special case, let http/1.1 clients connect to h2 servers as if they
-	// didn't support ALPN. We used not to enforce protocol overlap, so over
-	// time a number of HTTP servers were configured with only "h2", but
-	// expected to accept connections from "http/1.1" clients. See Issue 46310.
-	if http11fallback {
-		return "", nil
-	}
-	return "", fmt.Errorf("tls: client requested unsupported application protocols (%s)", clientProtos)
-}
-
-// supportsECDHE returns whether ECDHE key exchanges can be used with this
-// pre-TLS 1.3 client.
-func supportsECDHE(c *Config, supportedCurves []CurveID, supportedPoints []uint8) bool {
-	supportsCurve := false
-	for _, curve := range supportedCurves {
-		if c.supportsCurve(curve) {
-			supportsCurve = true
-			break
-		}
-	}
-
-	supportsPointFormat := false
-	for _, pointFormat := range supportedPoints {
-		if pointFormat == pointFormatUncompressed {
-			supportsPointFormat = true
-			break
-		}
-	}
-
-	return supportsCurve && supportsPointFormat
-}
-
-func (hs *serverHandshakeState) pickCipherSuite() error {
-	c := hs.c
-
-	preferenceOrder := cipherSuitesPreferenceOrder
-	if !hasAESGCMHardwareSupport || !aesgcmPreferred(hs.clientHello.cipherSuites) {
-		preferenceOrder = cipherSuitesPreferenceOrderNoAES
-	}
-
-	configCipherSuites := c.config.cipherSuites()
-	preferenceList := make([]uint16, 0, len(configCipherSuites))
-	for _, suiteID := range preferenceOrder {
-		for _, id := range configCipherSuites {
-			if id == suiteID {
-				preferenceList = append(preferenceList, id)
-				break
-			}
-		}
-	}
-
-	hs.suite = selectCipherSuite(preferenceList, hs.clientHello.cipherSuites, hs.cipherSuiteOk)
-	if hs.suite == nil {
-		c.sendAlert(alertHandshakeFailure)
-		return errors.New("tls: no cipher suite supported by both client and server")
-	}
-	c.cipherSuite = hs.suite.id
-
-	for _, id := range hs.clientHello.cipherSuites {
-		if id == TLS_FALLBACK_SCSV {
-			// The client is doing a fallback connection. See RFC 7507.
-			if hs.clientHello.vers < c.config.maxSupportedVersion(roleServer) {
-				c.sendAlert(alertInappropriateFallback)
-				return errors.New("tls: client using inappropriate protocol fallback")
-			}
-			break
-		}
-	}
-
-	return nil
-}
-
-func (hs *serverHandshakeState) cipherSuiteOk(c *cipherSuite) bool {
-	if c.flags&suiteECDHE != 0 {
-		if !hs.ecdheOk {
-			return false
-		}
-		if c.flags&suiteECSign != 0 {
-			if !hs.ecSignOk {
-				return false
-			}
-		} else if !hs.rsaSignOk {
-			return false
-		}
-	} else if !hs.rsaDecryptOk {
-		return false
-	}
-	if hs.c.vers < VersionTLS12 && c.flags&suiteTLS12 != 0 {
-		return false
-	}
-	return true
-}
-
-// checkForResumption reports whether we should perform resumption on this connection.
-func (hs *serverHandshakeState) checkForResumption() bool {
-	c := hs.c
-
-	if c.config.SessionTicketsDisabled {
-		return false
-	}
-
-	plaintext, usedOldKey := c.decryptTicket(hs.clientHello.sessionTicket)
-	if plaintext == nil {
-		return false
-	}
-	hs.sessionState = &sessionState{usedOldKey: usedOldKey}
-	ok := hs.sessionState.unmarshal(plaintext)
-	if !ok {
-		return false
-	}
-
-	createdAt := time.Unix(int64(hs.sessionState.createdAt), 0)
-	if c.config.time().Sub(createdAt) > maxSessionTicketLifetime {
-		return false
-	}
-
-	// Never resume a session for a different TLS version.
-	if c.vers != hs.sessionState.vers {
-		return false
-	}
-
-	cipherSuiteOk := false
-	// Check that the client is still offering the ciphersuite in the session.
-	for _, id := range hs.clientHello.cipherSuites {
-		if id == hs.sessionState.cipherSuite {
-			cipherSuiteOk = true
-			break
-		}
-	}
-	if !cipherSuiteOk {
-		return false
-	}
-
-	// Check that we also support the ciphersuite from the session.
-	hs.suite = selectCipherSuite([]uint16{hs.sessionState.cipherSuite},
-		c.config.cipherSuites(), hs.cipherSuiteOk)
-	if hs.suite == nil {
-		return false
-	}
-
-	sessionHasClientCerts := len(hs.sessionState.certificates) != 0
-	needClientCerts := requiresClientCert(c.config.ClientAuth)
-	if needClientCerts && !sessionHasClientCerts {
-		return false
-	}
-	if sessionHasClientCerts && c.config.ClientAuth == NoClientCert {
-		return false
-	}
-
-	return true
-}
-
-func (hs *serverHandshakeState) doResumeHandshake() error {
-	c := hs.c
-
-	hs.hello.cipherSuite = hs.suite.id
-	c.cipherSuite = hs.suite.id
-	// We echo the client's session ID in the ServerHello to let it know
-	// that we're doing a resumption.
-	hs.hello.sessionId = hs.clientHello.sessionId
-	hs.hello.ticketSupported = hs.sessionState.usedOldKey
-	hs.finishedHash = newFinishedHash(c.vers, hs.suite)
-	hs.finishedHash.discardHandshakeBuffer()
-	hs.finishedHash.Write(hs.clientHello.marshal())
-	hs.finishedHash.Write(hs.hello.marshal())
-	if _, err := c.writeRecord(recordTypeHandshake, hs.hello.marshal()); err != nil {
-		return err
-	}
-
-	if err := c.processCertsFromClient(Certificate{
-		Certificate: hs.sessionState.certificates,
-	}); err != nil {
-		return err
-	}
-
-	if c.config.VerifyConnection != nil {
-		if err := c.config.VerifyConnection(c.connectionStateLocked()); err != nil {
-			c.sendAlert(alertBadCertificate)
-			return err
-		}
-	}
-
-	hs.masterSecret = hs.sessionState.masterSecret
-
-	return nil
-}
-
-func (hs *serverHandshakeState) doFullHandshake() error {
-	c := hs.c
-
-	if hs.clientHello.ocspStapling && len(hs.cert.OCSPStaple) > 0 {
-		hs.hello.ocspStapling = true
-	}
-
-	hs.hello.ticketSupported = hs.clientHello.ticketSupported && !c.config.SessionTicketsDisabled
-	hs.hello.cipherSuite = hs.suite.id
-
-	hs.finishedHash = newFinishedHash(hs.c.vers, hs.suite)
-	if c.config.ClientAuth == NoClientCert {
-		// No need to keep a full record of the handshake if client
-		// certificates won't be used.
-		hs.finishedHash.discardHandshakeBuffer()
-	}
-	hs.finishedHash.Write(hs.clientHello.marshal())
-	hs.finishedHash.Write(hs.hello.marshal())
-	if _, err := c.writeRecord(recordTypeHandshake, hs.hello.marshal()); err != nil {
-		return err
-	}
-
-	certMsg := new(certificateMsg)
-	certMsg.certificates = hs.cert.Certificate
-	hs.finishedHash.Write(certMsg.marshal())
-	if _, err := c.writeRecord(recordTypeHandshake, certMsg.marshal()); err != nil {
-		return err
-	}
-
-	if hs.hello.ocspStapling {
-		certStatus := new(certificateStatusMsg)
-		certStatus.response = hs.cert.OCSPStaple
-		hs.finishedHash.Write(certStatus.marshal())
-		if _, err := c.writeRecord(recordTypeHandshake, certStatus.marshal()); err != nil {
-			return err
-		}
-	}
-
-	keyAgreement := hs.suite.ka(c.vers)
-	skx, err := keyAgreement.generateServerKeyExchange(c.config, hs.cert, hs.clientHello, hs.hello)
-	if err != nil {
-		c.sendAlert(alertHandshakeFailure)
-		return err
-	}
-	if skx != nil {
-		hs.finishedHash.Write(skx.marshal())
-		if _, err := c.writeRecord(recordTypeHandshake, skx.marshal()); err != nil {
-			return err
-		}
-	}
-
-	var certReq *certificateRequestMsg
-	if c.config.ClientAuth >= RequestClientCert {
-		// Request a client certificate
-		certReq = new(certificateRequestMsg)
-		certReq.certificateTypes = []byte{
-			byte(certTypeRSASign),
-			byte(certTypeECDSASign),
-		}
-		if c.vers >= VersionTLS12 {
-			certReq.hasSignatureAlgorithm = true
-			certReq.supportedSignatureAlgorithms = supportedSignatureAlgorithms
-		}
-
-		// An empty list of certificateAuthorities signals to
-		// the client that it may send any certificate in response
-		// to our request. When we know the CAs we trust, then
-		// we can send them down, so that the client can choose
-		// an appropriate certificate to give to us.
-		if c.config.ClientCAs != nil {
-			certReq.certificateAuthorities = c.config.ClientCAs.Subjects()
-		}
-		hs.finishedHash.Write(certReq.marshal())
-		if _, err := c.writeRecord(recordTypeHandshake, certReq.marshal()); err != nil {
-			return err
-		}
-	}
-
-	helloDone := new(serverHelloDoneMsg)
-	hs.finishedHash.Write(helloDone.marshal())
-	if _, err := c.writeRecord(recordTypeHandshake, helloDone.marshal()); err != nil {
-		return err
-	}
-
-	if _, err := c.flush(); err != nil {
-		return err
-	}
-
-	var pub crypto.PublicKey // public key for client auth, if any
-
-	msg, err := c.readHandshake()
-	if err != nil {
-		return err
-	}
-
-	// If we requested a client certificate, then the client must send a
-	// certificate message, even if it's empty.
-	if c.config.ClientAuth >= RequestClientCert {
-		certMsg, ok := msg.(*certificateMsg)
-		if !ok {
-			c.sendAlert(alertUnexpectedMessage)
-			return unexpectedMessageError(certMsg, msg)
-		}
-		hs.finishedHash.Write(certMsg.marshal())
-
-		if err := c.processCertsFromClient(Certificate{
-			Certificate: certMsg.certificates,
-		}); err != nil {
-			return err
-		}
-		if len(certMsg.certificates) != 0 {
-			pub = c.peerCertificates[0].PublicKey
-		}
-
-		msg, err = c.readHandshake()
-		if err != nil {
-			return err
-		}
-	}
-	if c.config.VerifyConnection != nil {
-		if err := c.config.VerifyConnection(c.connectionStateLocked()); err != nil {
-			c.sendAlert(alertBadCertificate)
-			return err
-		}
-	}
-
-	// Get client key exchange
-	ckx, ok := msg.(*clientKeyExchangeMsg)
-	if !ok {
-		c.sendAlert(alertUnexpectedMessage)
-		return unexpectedMessageError(ckx, msg)
-	}
-	hs.finishedHash.Write(ckx.marshal())
-
-	preMasterSecret, err := keyAgreement.processClientKeyExchange(c.config, hs.cert, ckx, c.vers)
-	if err != nil {
-		c.sendAlert(alertHandshakeFailure)
-		return err
-	}
-	hs.masterSecret = masterFromPreMasterSecret(c.vers, hs.suite, preMasterSecret, hs.clientHello.random, hs.hello.random)
-	if err := c.config.writeKeyLog(keyLogLabelTLS12, hs.clientHello.random, hs.masterSecret); err != nil {
-		c.sendAlert(alertInternalError)
-		return err
-	}
-
-	// If we received a client cert in response to our certificate request message,
-	// the client will send us a certificateVerifyMsg immediately after the
-	// clientKeyExchangeMsg. This message is a digest of all preceding
-	// handshake-layer messages that is signed using the private key corresponding
-	// to the client's certificate. This allows us to verify that the client is in
-	// possession of the private key of the certificate.
-	if len(c.peerCertificates) > 0 {
-		msg, err = c.readHandshake()
-		if err != nil {
-			return err
-		}
-		certVerify, ok := msg.(*certificateVerifyMsg)
-		if !ok {
-			c.sendAlert(alertUnexpectedMessage)
-			return unexpectedMessageError(certVerify, msg)
-		}
-
-		var sigType uint8
-		var sigHash crypto.Hash
-		if c.vers >= VersionTLS12 {
-			if !isSupportedSignatureAlgorithm(certVerify.signatureAlgorithm, certReq.supportedSignatureAlgorithms) {
-				c.sendAlert(alertIllegalParameter)
-				return errors.New("tls: client certificate used with invalid signature algorithm")
-			}
-			sigType, sigHash, err = typeAndHashFromSignatureScheme(certVerify.signatureAlgorithm)
-			if err != nil {
-				return c.sendAlert(alertInternalError)
-			}
-		} else {
-			sigType, sigHash, err = legacyTypeAndHashFromPublicKey(pub)
-			if err != nil {
-				c.sendAlert(alertIllegalParameter)
-				return err
-			}
-		}
-
-		signed := hs.finishedHash.hashForClientCertificate(sigType, sigHash, hs.masterSecret)
-		if err := verifyHandshakeSignature(sigType, pub, sigHash, signed, certVerify.signature); err != nil {
-			c.sendAlert(alertDecryptError)
-			return errors.New("tls: invalid signature by the client certificate: " + err.Error())
-		}
-
-		hs.finishedHash.Write(certVerify.marshal())
-	}
-
-	hs.finishedHash.discardHandshakeBuffer()
-
-	return nil
-}
-
-func (hs *serverHandshakeState) establishKeys() error {
-	c := hs.c
-
-	clientMAC, serverMAC, clientKey, serverKey, clientIV, serverIV :=
-		keysFromMasterSecret(c.vers, hs.suite, hs.masterSecret, hs.clientHello.random, hs.hello.random, hs.suite.macLen, hs.suite.keyLen, hs.suite.ivLen)
-
-	var clientCipher, serverCipher any
-	var clientHash, serverHash hash.Hash
-
-	if hs.suite.aead == nil {
-		clientCipher = hs.suite.cipher(clientKey, clientIV, true /* for reading */)
-		clientHash = hs.suite.mac(clientMAC)
-		serverCipher = hs.suite.cipher(serverKey, serverIV, false /* not for reading */)
-		serverHash = hs.suite.mac(serverMAC)
-	} else {
-		clientCipher = hs.suite.aead(clientKey, clientIV)
-		serverCipher = hs.suite.aead(serverKey, serverIV)
-	}
-
-	c.in.prepareCipherSpec(c.vers, clientCipher, clientHash)
-	c.out.prepareCipherSpec(c.vers, serverCipher, serverHash)
-
-	return nil
-}
-
-func (hs *serverHandshakeState) readFinished(out []byte) error {
-	c := hs.c
-
-	if err := c.readChangeCipherSpec(); err != nil {
-		return err
-	}
-
-	msg, err := c.readHandshake()
-	if err != nil {
-		return err
-	}
-	clientFinished, ok := msg.(*finishedMsg)
-	if !ok {
-		c.sendAlert(alertUnexpectedMessage)
-		return unexpectedMessageError(clientFinished, msg)
-	}
-
-	verify := hs.finishedHash.clientSum(hs.masterSecret)
-	if len(verify) != len(clientFinished.verifyData) ||
-		subtle.ConstantTimeCompare(verify, clientFinished.verifyData) != 1 {
-		c.sendAlert(alertHandshakeFailure)
-		return errors.New("tls: client's Finished message is incorrect")
-	}
-
-	hs.finishedHash.Write(clientFinished.marshal())
-	copy(out, verify)
-	return nil
-}
-
-func (hs *serverHandshakeState) sendSessionTicket() error {
-	// ticketSupported is set in a resumption handshake if the
-	// ticket from the client was encrypted with an old session
-	// ticket key and thus a refreshed ticket should be sent.
-	if !hs.hello.ticketSupported {
-		return nil
-	}
-
-	c := hs.c
-	m := new(newSessionTicketMsg)
-
-	createdAt := uint64(c.config.time().Unix())
-	if hs.sessionState != nil {
-		// If this is re-wrapping an old key, then keep
-		// the original time it was created.
-		createdAt = hs.sessionState.createdAt
-	}
-
-	var certsFromClient [][]byte
-	for _, cert := range c.peerCertificates {
-		certsFromClient = append(certsFromClient, cert.Raw)
-	}
-	state := sessionState{
-		vers:         c.vers,
-		cipherSuite:  hs.suite.id,
-		createdAt:    createdAt,
-		masterSecret: hs.masterSecret,
-		certificates: certsFromClient,
-	}
-	var err error
-	m.ticket, err = c.encryptTicket(state.marshal())
-	if err != nil {
-		return err
-	}
-
-	hs.finishedHash.Write(m.marshal())
-	if _, err := c.writeRecord(recordTypeHandshake, m.marshal()); err != nil {
-		return err
-	}
-
-	return nil
-}
-
-func (hs *serverHandshakeState) sendFinished(out []byte) error {
-	c := hs.c
-
-	if _, err := c.writeRecord(recordTypeChangeCipherSpec, []byte{1}); err != nil {
-		return err
-	}
-
-	finished := new(finishedMsg)
-	finished.verifyData = hs.finishedHash.serverSum(hs.masterSecret)
-	hs.finishedHash.Write(finished.marshal())
-	if _, err := c.writeRecord(recordTypeHandshake, finished.marshal()); err != nil {
-		return err
-	}
-
-	copy(out, finished.verifyData)
-
-	return nil
-}
-
-// processCertsFromClient takes a chain of client certificates either from a
-// Certificates message or from a sessionState and verifies them. It returns
-// the public key of the leaf certificate.
-func (c *Conn) processCertsFromClient(certificate Certificate) error {
-	certificates := certificate.Certificate
-	certs := make([]*x509.Certificate, len(certificates))
-	var err error
-	for i, asn1Data := range certificates {
-		if certs[i], err = x509.ParseCertificate(asn1Data); err != nil {
-			c.sendAlert(alertBadCertificate)
-			return errors.New("tls: failed to parse client certificate: " + err.Error())
-		}
-	}
-
-	if len(certs) == 0 && requiresClientCert(c.config.ClientAuth) {
-		c.sendAlert(alertBadCertificate)
-		return errors.New("tls: client didn't provide a certificate")
-	}
-
-	if c.config.ClientAuth >= VerifyClientCertIfGiven && len(certs) > 0 {
-		opts := x509.VerifyOptions{
-			Roots:         c.config.ClientCAs,
-			CurrentTime:   c.config.time(),
-			Intermediates: x509.NewCertPool(),
-			KeyUsages:     []x509.ExtKeyUsage{x509.ExtKeyUsageClientAuth},
-		}
-
-		for _, cert := range certs[1:] {
-			opts.Intermediates.AddCert(cert)
-		}
-
-		chains, err := certs[0].Verify(opts)
-		if err != nil {
-			c.sendAlert(alertBadCertificate)
-			return errors.New("tls: failed to verify client certificate: " + err.Error())
-		}
-
-		c.verifiedChains = chains
-	}
-
-	c.peerCertificates = certs
-	c.ocspResponse = certificate.OCSPStaple
-	c.scts = certificate.SignedCertificateTimestamps
-
-	if len(certs) > 0 {
-		switch certs[0].PublicKey.(type) {
-		case *ecdsa.PublicKey, *rsa.PublicKey, ed25519.PublicKey:
-		default:
-			c.sendAlert(alertUnsupportedCertificate)
-			return fmt.Errorf("tls: client certificate contains an unsupported public key of type %T", certs[0].PublicKey)
-		}
-	}
-
-	if c.config.VerifyPeerCertificate != nil {
-		if err := c.config.VerifyPeerCertificate(certificates, c.verifiedChains); err != nil {
-			c.sendAlert(alertBadCertificate)
-			return err
-		}
-	}
-
-	return nil
-}
-
-func clientHelloInfo(ctx context.Context, c *Conn, clientHello *clientHelloMsg) *ClientHelloInfo {
-	supportedVersions := clientHello.supportedVersions
-	if len(clientHello.supportedVersions) == 0 {
-		supportedVersions = supportedVersionsFromMax(clientHello.vers)
-	}
-
-	return &ClientHelloInfo{
-		CipherSuites:      clientHello.cipherSuites,
-		ServerName:        clientHello.serverName,
-		SupportedCurves:   clientHello.supportedCurves,
-		SupportedPoints:   clientHello.supportedPoints,
-		SignatureSchemes:  clientHello.supportedSignatureAlgorithms,
-		SupportedProtos:   clientHello.alpnProtocols,
-		SupportedVersions: supportedVersions,
-		Conn:              c.conn,
-		config:            c.config,
-		ctx:               ctx,
-	}
-}
diff --git a/contrib/go/_std_1.18/src/crypto/tls/handshake_server_tls13.go b/contrib/go/_std_1.18/src/crypto/tls/handshake_server_tls13.go
deleted file mode 100644
index 54e612ae04..0000000000
--- a/contrib/go/_std_1.18/src/crypto/tls/handshake_server_tls13.go
+++ /dev/null
@@ -1,872 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package tls
-
-import (
-	"bytes"
-	"context"
-	"crypto"
-	"crypto/hmac"
-	"crypto/rsa"
-	"encoding/binary"
-	"errors"
-	"hash"
-	"io"
-	"sync/atomic"
-	"time"
-)
-
-// maxClientPSKIdentities is the number of client PSK identities the server will
-// attempt to validate. It will ignore the rest not to let cheap ClientHello
-// messages cause too much work in session ticket decryption attempts.
-const maxClientPSKIdentities = 5
-
-type serverHandshakeStateTLS13 struct {
-	c               *Conn
-	ctx             context.Context
-	clientHello     *clientHelloMsg
-	hello           *serverHelloMsg
-	sentDummyCCS    bool
-	usingPSK        bool
-	suite           *cipherSuiteTLS13
-	cert            *Certificate
-	sigAlg          SignatureScheme
-	earlySecret     []byte
-	sharedKey       []byte
-	handshakeSecret []byte
-	masterSecret    []byte
-	trafficSecret   []byte // client_application_traffic_secret_0
-	transcript      hash.Hash
-	clientFinished  []byte
-}
-
-func (hs *serverHandshakeStateTLS13) handshake() error {
-	c := hs.c
-
-	// For an overview of the TLS 1.3 handshake, see RFC 8446, Section 2.
-	if err := hs.processClientHello(); err != nil {
-		return err
-	}
-	if err := hs.checkForResumption(); err != nil {
-		return err
-	}
-	if err := hs.pickCertificate(); err != nil {
-		return err
-	}
-	c.buffering = true
-	if err := hs.sendServerParameters(); err != nil {
-		return err
-	}
-	if err := hs.sendServerCertificate(); err != nil {
-		return err
-	}
-	if err := hs.sendServerFinished(); err != nil {
-		return err
-	}
-	// Note that at this point we could start sending application data without
-	// waiting for the client's second flight, but the application might not
-	// expect the lack of replay protection of the ClientHello parameters.
-	if _, err := c.flush(); err != nil {
-		return err
-	}
-	if err := hs.readClientCertificate(); err != nil {
-		return err
-	}
-	if err := hs.readClientFinished(); err != nil {
-		return err
-	}
-
-	atomic.StoreUint32(&c.handshakeStatus, 1)
-
-	return nil
-}
-
-func (hs *serverHandshakeStateTLS13) processClientHello() error {
-	c := hs.c
-
-	hs.hello = new(serverHelloMsg)
-
-	// TLS 1.3 froze the ServerHello.legacy_version field, and uses
-	// supported_versions instead. See RFC 8446, sections 4.1.3 and 4.2.1.
-	hs.hello.vers = VersionTLS12
-	hs.hello.supportedVersion = c.vers
-
-	if len(hs.clientHello.supportedVersions) == 0 {
-		c.sendAlert(alertIllegalParameter)
-		return errors.New("tls: client used the legacy version field to negotiate TLS 1.3")
-	}
-
-	// Abort if the client is doing a fallback and landing lower than what we
-	// support. See RFC 7507, which however does not specify the interaction
-	// with supported_versions. The only difference is that with
-	// supported_versions a client has a chance to attempt a [TLS 1.2, TLS 1.4]
-	// handshake in case TLS 1.3 is broken but 1.2 is not. Alas, in that case,
-	// it will have to drop the TLS_FALLBACK_SCSV protection if it falls back to
-	// TLS 1.2, because a TLS 1.3 server would abort here. The situation before
-	// supported_versions was not better because there was just no way to do a
-	// TLS 1.4 handshake without risking the server selecting TLS 1.3.
-	for _, id := range hs.clientHello.cipherSuites {
-		if id == TLS_FALLBACK_SCSV {
-			// Use c.vers instead of max(supported_versions) because an attacker
-			// could defeat this by adding an arbitrary high version otherwise.
-			if c.vers < c.config.maxSupportedVersion(roleServer) {
-				c.sendAlert(alertInappropriateFallback)
-				return errors.New("tls: client using inappropriate protocol fallback")
-			}
-			break
-		}
-	}
-
-	if len(hs.clientHello.compressionMethods) != 1 ||
-		hs.clientHello.compressionMethods[0] != compressionNone {
-		c.sendAlert(alertIllegalParameter)
-		return errors.New("tls: TLS 1.3 client supports illegal compression methods")
-	}
-
-	hs.hello.random = make([]byte, 32)
-	if _, err := io.ReadFull(c.config.rand(), hs.hello.random); err != nil {
-		c.sendAlert(alertInternalError)
-		return err
-	}
-
-	if len(hs.clientHello.secureRenegotiation) != 0 {
-		c.sendAlert(alertHandshakeFailure)
-		return errors.New("tls: initial handshake had non-empty renegotiation extension")
-	}
-
-	if hs.clientHello.earlyData {
-		// See RFC 8446, Section 4.2.10 for the complicated behavior required
-		// here. The scenario is that a different server at our address offered
-		// to accept early data in the past, which we can't handle. For now, all
-		// 0-RTT enabled session tickets need to expire before a Go server can
-		// replace a server or join a pool. That's the same requirement that
-		// applies to mixing or replacing with any TLS 1.2 server.
-		c.sendAlert(alertUnsupportedExtension)
-		return errors.New("tls: client sent unexpected early data")
-	}
-
-	hs.hello.sessionId = hs.clientHello.sessionId
-	hs.hello.compressionMethod = compressionNone
-
-	preferenceList := defaultCipherSuitesTLS13
-	if !hasAESGCMHardwareSupport || !aesgcmPreferred(hs.clientHello.cipherSuites) {
-		preferenceList = defaultCipherSuitesTLS13NoAES
-	}
-	for _, suiteID := range preferenceList {
-		hs.suite = mutualCipherSuiteTLS13(hs.clientHello.cipherSuites, suiteID)
-		if hs.suite != nil {
-			break
-		}
-	}
-	if hs.suite == nil {
-		c.sendAlert(alertHandshakeFailure)
-		return errors.New("tls: no cipher suite supported by both client and server")
-	}
-	c.cipherSuite = hs.suite.id
-	hs.hello.cipherSuite = hs.suite.id
-	hs.transcript = hs.suite.hash.New()
-
-	// Pick the ECDHE group in server preference order, but give priority to
-	// groups with a key share, to avoid a HelloRetryRequest round-trip.
-	var selectedGroup CurveID
-	var clientKeyShare *keyShare
-GroupSelection:
-	for _, preferredGroup := range c.config.curvePreferences() {
-		for _, ks := range hs.clientHello.keyShares {
-			if ks.group == preferredGroup {
-				selectedGroup = ks.group
-				clientKeyShare = &ks
-				break GroupSelection
-			}
-		}
-		if selectedGroup != 0 {
-			continue
-		}
-		for _, group := range hs.clientHello.supportedCurves {
-			if group == preferredGroup {
-				selectedGroup = group
-				break
-			}
-		}
-	}
-	if selectedGroup == 0 {
-		c.sendAlert(alertHandshakeFailure)
-		return errors.New("tls: no ECDHE curve supported by both client and server")
-	}
-	if clientKeyShare == nil {
-		if err := hs.doHelloRetryRequest(selectedGroup); err != nil {
-			return err
-		}
-		clientKeyShare = &hs.clientHello.keyShares[0]
-	}
-
-	if _, ok := curveForCurveID(selectedGroup); selectedGroup != X25519 && !ok {
-		c.sendAlert(alertInternalError)
-		return errors.New("tls: CurvePreferences includes unsupported curve")
-	}
-	params, err := generateECDHEParameters(c.config.rand(), selectedGroup)
-	if err != nil {
-		c.sendAlert(alertInternalError)
-		return err
-	}
-	hs.hello.serverShare = keyShare{group: selectedGroup, data: params.PublicKey()}
-	hs.sharedKey = params.SharedKey(clientKeyShare.data)
-	if hs.sharedKey == nil {
-		c.sendAlert(alertIllegalParameter)
-		return errors.New("tls: invalid client key share")
-	}
-
-	c.serverName = hs.clientHello.serverName
-	return nil
-}
-
-func (hs *serverHandshakeStateTLS13) checkForResumption() error {
-	c := hs.c
-
-	if c.config.SessionTicketsDisabled {
-		return nil
-	}
-
-	modeOK := false
-	for _, mode := range hs.clientHello.pskModes {
-		if mode == pskModeDHE {
-			modeOK = true
-			break
-		}
-	}
-	if !modeOK {
-		return nil
-	}
-
-	if len(hs.clientHello.pskIdentities) != len(hs.clientHello.pskBinders) {
-		c.sendAlert(alertIllegalParameter)
-		return errors.New("tls: invalid or missing PSK binders")
-	}
-	if len(hs.clientHello.pskIdentities) == 0 {
-		return nil
-	}
-
-	for i, identity := range hs.clientHello.pskIdentities {
-		if i >= maxClientPSKIdentities {
-			break
-		}
-
-		plaintext, _ := c.decryptTicket(identity.label)
-		if plaintext == nil {
-			continue
-		}
-		sessionState := new(sessionStateTLS13)
-		if ok := sessionState.unmarshal(plaintext); !ok {
-			continue
-		}
-
-		createdAt := time.Unix(int64(sessionState.createdAt), 0)
-		if c.config.time().Sub(createdAt) > maxSessionTicketLifetime {
-			continue
-		}
-
-		// We don't check the obfuscated ticket age because it's affected by
-		// clock skew and it's only a freshness signal useful for shrinking the
-		// window for replay attacks, which don't affect us as we don't do 0-RTT.
-
-		pskSuite := cipherSuiteTLS13ByID(sessionState.cipherSuite)
-		if pskSuite == nil || pskSuite.hash != hs.suite.hash {
-			continue
-		}
-
-		// PSK connections don't re-establish client certificates, but carry
-		// them over in the session ticket. Ensure the presence of client certs
-		// in the ticket is consistent with the configured requirements.
-		sessionHasClientCerts := len(sessionState.certificate.Certificate) != 0
-		needClientCerts := requiresClientCert(c.config.ClientAuth)
-		if needClientCerts && !sessionHasClientCerts {
-			continue
-		}
-		if sessionHasClientCerts && c.config.ClientAuth == NoClientCert {
-			continue
-		}
-
-		psk := hs.suite.expandLabel(sessionState.resumptionSecret, "resumption",
-			nil, hs.suite.hash.Size())
-		hs.earlySecret = hs.suite.extract(psk, nil)
-		binderKey := hs.suite.deriveSecret(hs.earlySecret, resumptionBinderLabel, nil)
-		// Clone the transcript in case a HelloRetryRequest was recorded.
-		transcript := cloneHash(hs.transcript, hs.suite.hash)
-		if transcript == nil {
-			c.sendAlert(alertInternalError)
-			return errors.New("tls: internal error: failed to clone hash")
-		}
-		transcript.Write(hs.clientHello.marshalWithoutBinders())
-		pskBinder := hs.suite.finishedHash(binderKey, transcript)
-		if !hmac.Equal(hs.clientHello.pskBinders[i], pskBinder) {
-			c.sendAlert(alertDecryptError)
-			return errors.New("tls: invalid PSK binder")
-		}
-
-		c.didResume = true
-		if err := c.processCertsFromClient(sessionState.certificate); err != nil {
-			return err
-		}
-
-		hs.hello.selectedIdentityPresent = true
-		hs.hello.selectedIdentity = uint16(i)
-		hs.usingPSK = true
-		return nil
-	}
-
-	return nil
-}
-
-// cloneHash uses the encoding.BinaryMarshaler and encoding.BinaryUnmarshaler
-// interfaces implemented by standard library hashes to clone the state of in
-// to a new instance of h. It returns nil if the operation fails.
-func cloneHash(in hash.Hash, h crypto.Hash) hash.Hash {
-	// Recreate the interface to avoid importing encoding.
-	type binaryMarshaler interface {
-		MarshalBinary() (data []byte, err error)
-		UnmarshalBinary(data []byte) error
-	}
-	marshaler, ok := in.(binaryMarshaler)
-	if !ok {
-		return nil
-	}
-	state, err := marshaler.MarshalBinary()
-	if err != nil {
-		return nil
-	}
-	out := h.New()
-	unmarshaler, ok := out.(binaryMarshaler)
-	if !ok {
-		return nil
-	}
-	if err := unmarshaler.UnmarshalBinary(state); err != nil {
-		return nil
-	}
-	return out
-}
-
-func (hs *serverHandshakeStateTLS13) pickCertificate() error {
-	c := hs.c
-
-	// Only one of PSK and certificates are used at a time.
-	if hs.usingPSK {
-		return nil
-	}
-
-	// signature_algorithms is required in TLS 1.3. See RFC 8446, Section 4.2.3.
-	if len(hs.clientHello.supportedSignatureAlgorithms) == 0 {
-		return c.sendAlert(alertMissingExtension)
-	}
-
-	certificate, err := c.config.getCertificate(clientHelloInfo(hs.ctx, c, hs.clientHello))
-	if err != nil {
-		if err == errNoCertificates {
-			c.sendAlert(alertUnrecognizedName)
-		} else {
-			c.sendAlert(alertInternalError)
-		}
-		return err
-	}
-	hs.sigAlg, err = selectSignatureScheme(c.vers, certificate, hs.clientHello.supportedSignatureAlgorithms)
-	if err != nil {
-		// getCertificate returned a certificate that is unsupported or
-		// incompatible with the client's signature algorithms.
-		c.sendAlert(alertHandshakeFailure)
-		return err
-	}
-	hs.cert = certificate
-
-	return nil
-}
-
-// sendDummyChangeCipherSpec sends a ChangeCipherSpec record for compatibility
-// with middleboxes that didn't implement TLS correctly. See RFC 8446, Appendix D.4.
-func (hs *serverHandshakeStateTLS13) sendDummyChangeCipherSpec() error {
-	if hs.sentDummyCCS {
-		return nil
-	}
-	hs.sentDummyCCS = true
-
-	_, err := hs.c.writeRecord(recordTypeChangeCipherSpec, []byte{1})
-	return err
-}
-
-func (hs *serverHandshakeStateTLS13) doHelloRetryRequest(selectedGroup CurveID) error {
-	c := hs.c
-
-	// The first ClientHello gets double-hashed into the transcript upon a
-	// HelloRetryRequest. See RFC 8446, Section 4.4.1.
-	hs.transcript.Write(hs.clientHello.marshal())
-	chHash := hs.transcript.Sum(nil)
-	hs.transcript.Reset()
-	hs.transcript.Write([]byte{typeMessageHash, 0, 0, uint8(len(chHash))})
-	hs.transcript.Write(chHash)
-
-	helloRetryRequest := &serverHelloMsg{
-		vers:              hs.hello.vers,
-		random:            helloRetryRequestRandom,
-		sessionId:         hs.hello.sessionId,
-		cipherSuite:       hs.hello.cipherSuite,
-		compressionMethod: hs.hello.compressionMethod,
-		supportedVersion:  hs.hello.supportedVersion,
-		selectedGroup:     selectedGroup,
-	}
-
-	hs.transcript.Write(helloRetryRequest.marshal())
-	if _, err := c.writeRecord(recordTypeHandshake, helloRetryRequest.marshal()); err != nil {
-		return err
-	}
-
-	if err := hs.sendDummyChangeCipherSpec(); err != nil {
-		return err
-	}
-
-	msg, err := c.readHandshake()
-	if err != nil {
-		return err
-	}
-
-	clientHello, ok := msg.(*clientHelloMsg)
-	if !ok {
-		c.sendAlert(alertUnexpectedMessage)
-		return unexpectedMessageError(clientHello, msg)
-	}
-
-	if len(clientHello.keyShares) != 1 || clientHello.keyShares[0].group != selectedGroup {
-		c.sendAlert(alertIllegalParameter)
-		return errors.New("tls: client sent invalid key share in second ClientHello")
-	}
-
-	if clientHello.earlyData {
-		c.sendAlert(alertIllegalParameter)
-		return errors.New("tls: client indicated early data in second ClientHello")
-	}
-
-	if illegalClientHelloChange(clientHello, hs.clientHello) {
-		c.sendAlert(alertIllegalParameter)
-		return errors.New("tls: client illegally modified second ClientHello")
-	}
-
-	hs.clientHello = clientHello
-	return nil
-}
-
-// illegalClientHelloChange reports whether the two ClientHello messages are
-// different, with the exception of the changes allowed before and after a
-// HelloRetryRequest. See RFC 8446, Section 4.1.2.
-func illegalClientHelloChange(ch, ch1 *clientHelloMsg) bool {
-	if len(ch.supportedVersions) != len(ch1.supportedVersions) ||
-		len(ch.cipherSuites) != len(ch1.cipherSuites) ||
-		len(ch.supportedCurves) != len(ch1.supportedCurves) ||
-		len(ch.supportedSignatureAlgorithms) != len(ch1.supportedSignatureAlgorithms) ||
-		len(ch.supportedSignatureAlgorithmsCert) != len(ch1.supportedSignatureAlgorithmsCert) ||
-		len(ch.alpnProtocols) != len(ch1.alpnProtocols) {
-		return true
-	}
-	for i := range ch.supportedVersions {
-		if ch.supportedVersions[i] != ch1.supportedVersions[i] {
-			return true
-		}
-	}
-	for i := range ch.cipherSuites {
-		if ch.cipherSuites[i] != ch1.cipherSuites[i] {
-			return true
-		}
-	}
-	for i := range ch.supportedCurves {
-		if ch.supportedCurves[i] != ch1.supportedCurves[i] {
-			return true
-		}
-	}
-	for i := range ch.supportedSignatureAlgorithms {
-		if ch.supportedSignatureAlgorithms[i] != ch1.supportedSignatureAlgorithms[i] {
-			return true
-		}
-	}
-	for i := range ch.supportedSignatureAlgorithmsCert {
-		if ch.supportedSignatureAlgorithmsCert[i] != ch1.supportedSignatureAlgorithmsCert[i] {
-			return true
-		}
-	}
-	for i := range ch.alpnProtocols {
-		if ch.alpnProtocols[i] != ch1.alpnProtocols[i] {
-			return true
-		}
-	}
-	return ch.vers != ch1.vers ||
-		!bytes.Equal(ch.random, ch1.random) ||
-		!bytes.Equal(ch.sessionId, ch1.sessionId) ||
-		!bytes.Equal(ch.compressionMethods, ch1.compressionMethods) ||
-		ch.serverName != ch1.serverName ||
-		ch.ocspStapling != ch1.ocspStapling ||
-		!bytes.Equal(ch.supportedPoints, ch1.supportedPoints) ||
-		ch.ticketSupported != ch1.ticketSupported ||
-		!bytes.Equal(ch.sessionTicket, ch1.sessionTicket) ||
-		ch.secureRenegotiationSupported != ch1.secureRenegotiationSupported ||
-		!bytes.Equal(ch.secureRenegotiation, ch1.secureRenegotiation) ||
-		ch.scts != ch1.scts ||
-		!bytes.Equal(ch.cookie, ch1.cookie) ||
-		!bytes.Equal(ch.pskModes, ch1.pskModes)
-}
-
-func (hs *serverHandshakeStateTLS13) sendServerParameters() error {
-	c := hs.c
-
-	hs.transcript.Write(hs.clientHello.marshal())
-	hs.transcript.Write(hs.hello.marshal())
-	if _, err := c.writeRecord(recordTypeHandshake, hs.hello.marshal()); err != nil {
-		return err
-	}
-
-	if err := hs.sendDummyChangeCipherSpec(); err != nil {
-		return err
-	}
-
-	earlySecret := hs.earlySecret
-	if earlySecret == nil {
-		earlySecret = hs.suite.extract(nil, nil)
-	}
-	hs.handshakeSecret = hs.suite.extract(hs.sharedKey,
-		hs.suite.deriveSecret(earlySecret, "derived", nil))
-
-	clientSecret := hs.suite.deriveSecret(hs.handshakeSecret,
-		clientHandshakeTrafficLabel, hs.transcript)
-	c.in.setTrafficSecret(hs.suite, clientSecret)
-	serverSecret := hs.suite.deriveSecret(hs.handshakeSecret,
-		serverHandshakeTrafficLabel, hs.transcript)
-	c.out.setTrafficSecret(hs.suite, serverSecret)
-
-	err := c.config.writeKeyLog(keyLogLabelClientHandshake, hs.clientHello.random, clientSecret)
-	if err != nil {
-		c.sendAlert(alertInternalError)
-		return err
-	}
-	err = c.config.writeKeyLog(keyLogLabelServerHandshake, hs.clientHello.random, serverSecret)
-	if err != nil {
-		c.sendAlert(alertInternalError)
-		return err
-	}
-
-	encryptedExtensions := new(encryptedExtensionsMsg)
-
-	selectedProto, err := negotiateALPN(c.config.NextProtos, hs.clientHello.alpnProtocols)
-	if err != nil {
-		c.sendAlert(alertNoApplicationProtocol)
-		return err
-	}
-	encryptedExtensions.alpnProtocol = selectedProto
-	c.clientProtocol = selectedProto
-
-	hs.transcript.Write(encryptedExtensions.marshal())
-	if _, err := c.writeRecord(recordTypeHandshake, encryptedExtensions.marshal()); err != nil {
-		return err
-	}
-
-	return nil
-}
-
-func (hs *serverHandshakeStateTLS13) requestClientCert() bool {
-	return hs.c.config.ClientAuth >= RequestClientCert && !hs.usingPSK
-}
-
-func (hs *serverHandshakeStateTLS13) sendServerCertificate() error {
-	c := hs.c
-
-	// Only one of PSK and certificates are used at a time.
-	if hs.usingPSK {
-		return nil
-	}
-
-	if hs.requestClientCert() {
-		// Request a client certificate
-		certReq := new(certificateRequestMsgTLS13)
-		certReq.ocspStapling = true
-		certReq.scts = true
-		certReq.supportedSignatureAlgorithms = supportedSignatureAlgorithms
-		if c.config.ClientCAs != nil {
-			certReq.certificateAuthorities = c.config.ClientCAs.Subjects()
-		}
-
-		hs.transcript.Write(certReq.marshal())
-		if _, err := c.writeRecord(recordTypeHandshake, certReq.marshal()); err != nil {
-			return err
-		}
-	}
-
-	certMsg := new(certificateMsgTLS13)
-
-	certMsg.certificate = *hs.cert
-	certMsg.scts = hs.clientHello.scts && len(hs.cert.SignedCertificateTimestamps) > 0
-	certMsg.ocspStapling = hs.clientHello.ocspStapling && len(hs.cert.OCSPStaple) > 0
-
-	hs.transcript.Write(certMsg.marshal())
-	if _, err := c.writeRecord(recordTypeHandshake, certMsg.marshal()); err != nil {
-		return err
-	}
-
-	certVerifyMsg := new(certificateVerifyMsg)
-	certVerifyMsg.hasSignatureAlgorithm = true
-	certVerifyMsg.signatureAlgorithm = hs.sigAlg
-
-	sigType, sigHash, err := typeAndHashFromSignatureScheme(hs.sigAlg)
-	if err != nil {
-		return c.sendAlert(alertInternalError)
-	}
-
-	signed := signedMessage(sigHash, serverSignatureContext, hs.transcript)
-	signOpts := crypto.SignerOpts(sigHash)
-	if sigType == signatureRSAPSS {
-		signOpts = &rsa.PSSOptions{SaltLength: rsa.PSSSaltLengthEqualsHash, Hash: sigHash}
-	}
-	sig, err := hs.cert.PrivateKey.(crypto.Signer).Sign(c.config.rand(), signed, signOpts)
-	if err != nil {
-		public := hs.cert.PrivateKey.(crypto.Signer).Public()
-		if rsaKey, ok := public.(*rsa.PublicKey); ok && sigType == signatureRSAPSS &&
-			rsaKey.N.BitLen()/8 < sigHash.Size()*2+2 { // key too small for RSA-PSS
-			c.sendAlert(alertHandshakeFailure)
-		} else {
-			c.sendAlert(alertInternalError)
-		}
-		return errors.New("tls: failed to sign handshake: " + err.Error())
-	}
-	certVerifyMsg.signature = sig
-
-	hs.transcript.Write(certVerifyMsg.marshal())
-	if _, err := c.writeRecord(recordTypeHandshake, certVerifyMsg.marshal()); err != nil {
-		return err
-	}
-
-	return nil
-}
-
-func (hs *serverHandshakeStateTLS13) sendServerFinished() error {
-	c := hs.c
-
-	finished := &finishedMsg{
-		verifyData: hs.suite.finishedHash(c.out.trafficSecret, hs.transcript),
-	}
-
-	hs.transcript.Write(finished.marshal())
-	if _, err := c.writeRecord(recordTypeHandshake, finished.marshal()); err != nil {
-		return err
-	}
-
-	// Derive secrets that take context through the server Finished.
-
-	hs.masterSecret = hs.suite.extract(nil,
-		hs.suite.deriveSecret(hs.handshakeSecret, "derived", nil))
-
-	hs.trafficSecret = hs.suite.deriveSecret(hs.masterSecret,
-		clientApplicationTrafficLabel, hs.transcript)
-	serverSecret := hs.suite.deriveSecret(hs.masterSecret,
-		serverApplicationTrafficLabel, hs.transcript)
-	c.out.setTrafficSecret(hs.suite, serverSecret)
-
-	err := c.config.writeKeyLog(keyLogLabelClientTraffic, hs.clientHello.random, hs.trafficSecret)
-	if err != nil {
-		c.sendAlert(alertInternalError)
-		return err
-	}
-	err = c.config.writeKeyLog(keyLogLabelServerTraffic, hs.clientHello.random, serverSecret)
-	if err != nil {
-		c.sendAlert(alertInternalError)
-		return err
-	}
-
-	c.ekm = hs.suite.exportKeyingMaterial(hs.masterSecret, hs.transcript)
-
-	// If we did not request client certificates, at this point we can
-	// precompute the client finished and roll the transcript forward to send
-	// session tickets in our first flight.
-	if !hs.requestClientCert() {
-		if err := hs.sendSessionTickets(); err != nil {
-			return err
-		}
-	}
-
-	return nil
-}
-
-func (hs *serverHandshakeStateTLS13) shouldSendSessionTickets() bool {
-	if hs.c.config.SessionTicketsDisabled {
-		return false
-	}
-
-	// Don't send tickets the client wouldn't use. See RFC 8446, Section 4.2.9.
-	for _, pskMode := range hs.clientHello.pskModes {
-		if pskMode == pskModeDHE {
-			return true
-		}
-	}
-	return false
-}
-
-func (hs *serverHandshakeStateTLS13) sendSessionTickets() error {
-	c := hs.c
-
-	hs.clientFinished = hs.suite.finishedHash(c.in.trafficSecret, hs.transcript)
-	finishedMsg := &finishedMsg{
-		verifyData: hs.clientFinished,
-	}
-	hs.transcript.Write(finishedMsg.marshal())
-
-	if !hs.shouldSendSessionTickets() {
-		return nil
-	}
-
-	resumptionSecret := hs.suite.deriveSecret(hs.masterSecret,
-		resumptionLabel, hs.transcript)
-
-	m := new(newSessionTicketMsgTLS13)
-
-	var certsFromClient [][]byte
-	for _, cert := range c.peerCertificates {
-		certsFromClient = append(certsFromClient, cert.Raw)
-	}
-	state := sessionStateTLS13{
-		cipherSuite:      hs.suite.id,
-		createdAt:        uint64(c.config.time().Unix()),
-		resumptionSecret: resumptionSecret,
-		certificate: Certificate{
-			Certificate:                 certsFromClient,
-			OCSPStaple:                  c.ocspResponse,
-			SignedCertificateTimestamps: c.scts,
-		},
-	}
-	var err error
-	m.label, err = c.encryptTicket(state.marshal())
-	if err != nil {
-		return err
-	}
-	m.lifetime = uint32(maxSessionTicketLifetime / time.Second)
-
-	// ticket_age_add is a random 32-bit value. See RFC 8446, section 4.6.1
-	// The value is not stored anywhere; we never need to check the ticket age
-	// because 0-RTT is not supported.
-	ageAdd := make([]byte, 4)
-	_, err = hs.c.config.rand().Read(ageAdd)
-	if err != nil {
-		return err
-	}
-	m.ageAdd = binary.LittleEndian.Uint32(ageAdd)
-
-	// ticket_nonce, which must be unique per connection, is always left at
-	// zero because we only ever send one ticket per connection.
-
-	if _, err := c.writeRecord(recordTypeHandshake, m.marshal()); err != nil {
-		return err
-	}
-
-	return nil
-}
-
-func (hs *serverHandshakeStateTLS13) readClientCertificate() error {
-	c := hs.c
-
-	if !hs.requestClientCert() {
-		// Make sure the connection is still being verified whether or not
-		// the server requested a client certificate.
-		if c.config.VerifyConnection != nil {
-			if err := c.config.VerifyConnection(c.connectionStateLocked()); err != nil {
-				c.sendAlert(alertBadCertificate)
-				return err
-			}
-		}
-		return nil
-	}
-
-	// If we requested a client certificate, then the client must send a
-	// certificate message. If it's empty, no CertificateVerify is sent.
-
-	msg, err := c.readHandshake()
-	if err != nil {
-		return err
-	}
-
-	certMsg, ok := msg.(*certificateMsgTLS13)
-	if !ok {
-		c.sendAlert(alertUnexpectedMessage)
-		return unexpectedMessageError(certMsg, msg)
-	}
-	hs.transcript.Write(certMsg.marshal())
-
-	if err := c.processCertsFromClient(certMsg.certificate); err != nil {
-		return err
-	}
-
-	if c.config.VerifyConnection != nil {
-		if err := c.config.VerifyConnection(c.connectionStateLocked()); err != nil {
-			c.sendAlert(alertBadCertificate)
-			return err
-		}
-	}
-
-	if len(certMsg.certificate.Certificate) != 0 {
-		msg, err = c.readHandshake()
-		if err != nil {
-			return err
-		}
-
-		certVerify, ok := msg.(*certificateVerifyMsg)
-		if !ok {
-			c.sendAlert(alertUnexpectedMessage)
-			return unexpectedMessageError(certVerify, msg)
-		}
-
-		// See RFC 8446, Section 4.4.3.
-		if !isSupportedSignatureAlgorithm(certVerify.signatureAlgorithm, supportedSignatureAlgorithms) {
-			c.sendAlert(alertIllegalParameter)
-			return errors.New("tls: client certificate used with invalid signature algorithm")
-		}
-		sigType, sigHash, err := typeAndHashFromSignatureScheme(certVerify.signatureAlgorithm)
-		if err != nil {
-			return c.sendAlert(alertInternalError)
-		}
-		if sigType == signaturePKCS1v15 || sigHash == crypto.SHA1 {
-			c.sendAlert(alertIllegalParameter)
-			return errors.New("tls: client certificate used with invalid signature algorithm")
-		}
-		signed := signedMessage(sigHash, clientSignatureContext, hs.transcript)
-		if err := verifyHandshakeSignature(sigType, c.peerCertificates[0].PublicKey,
-			sigHash, signed, certVerify.signature); err != nil {
-			c.sendAlert(alertDecryptError)
-			return errors.New("tls: invalid signature by the client certificate: " + err.Error())
-		}
-
-		hs.transcript.Write(certVerify.marshal())
-	}
-
-	// If we waited until the client certificates to send session tickets, we
-	// are ready to do it now.
-	if err := hs.sendSessionTickets(); err != nil {
-		return err
-	}
-
-	return nil
-}
-
-func (hs *serverHandshakeStateTLS13) readClientFinished() error {
-	c := hs.c
-
-	msg, err := c.readHandshake()
-	if err != nil {
-		return err
-	}
-
-	finished, ok := msg.(*finishedMsg)
-	if !ok {
-		c.sendAlert(alertUnexpectedMessage)
-		return unexpectedMessageError(finished, msg)
-	}
-
-	if !hmac.Equal(hs.clientFinished, finished.verifyData) {
-		c.sendAlert(alertDecryptError)
-		return errors.New("tls: invalid client finished hash")
-	}
-
-	c.in.setTrafficSecret(hs.suite, hs.trafficSecret)
-
-	return nil
-}
diff --git a/contrib/go/_std_1.18/src/crypto/x509/cert_pool.go b/contrib/go/_std_1.18/src/crypto/x509/cert_pool.go
deleted file mode 100644
index 873ffeee1d..0000000000
--- a/contrib/go/_std_1.18/src/crypto/x509/cert_pool.go
+++ /dev/null
@@ -1,251 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package x509
-
-import (
-	"bytes"
-	"crypto/sha256"
-	"encoding/pem"
-	"sync"
-)
-
-type sum224 [sha256.Size224]byte
-
-// CertPool is a set of certificates.
-type CertPool struct {
-	byName map[string][]int // cert.RawSubject => index into lazyCerts
-
-	// lazyCerts contains funcs that return a certificate,
-	// lazily parsing/decompressing it as needed.
-	lazyCerts []lazyCert
-
-	// haveSum maps from sum224(cert.Raw) to true. It's used only
-	// for AddCert duplicate detection, to avoid CertPool.contains
-	// calls in the AddCert path (because the contains method can
-	// call getCert and otherwise negate savings from lazy getCert
-	// funcs).
-	haveSum map[sum224]bool
-
-	// systemPool indicates whether this is a special pool derived from the
-	// system roots. If it includes additional roots, it requires doing two
-	// verifications, one using the roots provided by the caller, and one using
-	// the system platform verifier.
-	systemPool bool
-}
-
-// lazyCert is minimal metadata about a Cert and a func to retrieve it
-// in its normal expanded *Certificate form.
-type lazyCert struct {
-	// rawSubject is the Certificate.RawSubject value.
-	// It's the same as the CertPool.byName key, but in []byte
-	// form to make CertPool.Subjects (as used by crypto/tls) do
-	// fewer allocations.
-	rawSubject []byte
-
-	// getCert returns the certificate.
-	//
-	// It is not meant to do network operations or anything else
-	// where a failure is likely; the func is meant to lazily
-	// parse/decompress data that is already known to be good. The
-	// error in the signature primarily is meant for use in the
-	// case where a cert file existed on local disk when the program
-	// started up is deleted later before it's read.
-	getCert func() (*Certificate, error)
-}
-
-// NewCertPool returns a new, empty CertPool.
-func NewCertPool() *CertPool {
-	return &CertPool{
-		byName:  make(map[string][]int),
-		haveSum: make(map[sum224]bool),
-	}
-}
-
-// len returns the number of certs in the set.
-// A nil set is a valid empty set.
-func (s *CertPool) len() int {
-	if s == nil {
-		return 0
-	}
-	return len(s.lazyCerts)
-}
-
-// cert returns cert index n in s.
-func (s *CertPool) cert(n int) (*Certificate, error) {
-	return s.lazyCerts[n].getCert()
-}
-
-func (s *CertPool) copy() *CertPool {
-	p := &CertPool{
-		byName:     make(map[string][]int, len(s.byName)),
-		lazyCerts:  make([]lazyCert, len(s.lazyCerts)),
-		haveSum:    make(map[sum224]bool, len(s.haveSum)),
-		systemPool: s.systemPool,
-	}
-	for k, v := range s.byName {
-		indexes := make([]int, len(v))
-		copy(indexes, v)
-		p.byName[k] = indexes
-	}
-	for k := range s.haveSum {
-		p.haveSum[k] = true
-	}
-	copy(p.lazyCerts, s.lazyCerts)
-	return p
-}
-
-// SystemCertPool returns a copy of the system cert pool.
-//
-// On Unix systems other than macOS the environment variables SSL_CERT_FILE and
-// SSL_CERT_DIR can be used to override the system default locations for the SSL
-// certificate file and SSL certificate files directory, respectively. The
-// latter can be a colon-separated list.
-//
-// Any mutations to the returned pool are not written to disk and do not affect
-// any other pool returned by SystemCertPool.
-//
-// New changes in the system cert pool might not be reflected in subsequent calls.
-func SystemCertPool() (*CertPool, error) {
-	if sysRoots := systemRootsPool(); sysRoots != nil {
-		return sysRoots.copy(), nil
-	}
-
-	return loadSystemRoots()
-}
-
-// findPotentialParents returns the indexes of certificates in s which might
-// have signed cert.
-func (s *CertPool) findPotentialParents(cert *Certificate) []*Certificate {
-	if s == nil {
-		return nil
-	}
-
-	// consider all candidates where cert.Issuer matches cert.Subject.
-	// when picking possible candidates the list is built in the order
-	// of match plausibility as to save cycles in buildChains:
-	//   AKID and SKID match
-	//   AKID present, SKID missing / AKID missing, SKID present
-	//   AKID and SKID don't match
-	var matchingKeyID, oneKeyID, mismatchKeyID []*Certificate
-	for _, c := range s.byName[string(cert.RawIssuer)] {
-		candidate, err := s.cert(c)
-		if err != nil {
-			continue
-		}
-		kidMatch := bytes.Equal(candidate.SubjectKeyId, cert.AuthorityKeyId)
-		switch {
-		case kidMatch:
-			matchingKeyID = append(matchingKeyID, candidate)
-		case (len(candidate.SubjectKeyId) == 0 && len(cert.AuthorityKeyId) > 0) ||
-			(len(candidate.SubjectKeyId) > 0 && len(cert.AuthorityKeyId) == 0):
-			oneKeyID = append(oneKeyID, candidate)
-		default:
-			mismatchKeyID = append(mismatchKeyID, candidate)
-		}
-	}
-
-	found := len(matchingKeyID) + len(oneKeyID) + len(mismatchKeyID)
-	if found == 0 {
-		return nil
-	}
-	candidates := make([]*Certificate, 0, found)
-	candidates = append(candidates, matchingKeyID...)
-	candidates = append(candidates, oneKeyID...)
-	candidates = append(candidates, mismatchKeyID...)
-	return candidates
-}
-
-func (s *CertPool) contains(cert *Certificate) bool {
-	if s == nil {
-		return false
-	}
-	return s.haveSum[sha256.Sum224(cert.Raw)]
-}
-
-// AddCert adds a certificate to a pool.
-func (s *CertPool) AddCert(cert *Certificate) {
-	if cert == nil {
-		panic("adding nil Certificate to CertPool")
-	}
-	s.addCertFunc(sha256.Sum224(cert.Raw), string(cert.RawSubject), func() (*Certificate, error) {
-		return cert, nil
-	})
-}
-
-// addCertFunc adds metadata about a certificate to a pool, along with
-// a func to fetch that certificate later when needed.
-//
-// The rawSubject is Certificate.RawSubject and must be non-empty.
-// The getCert func may be called 0 or more times.
-func (s *CertPool) addCertFunc(rawSum224 sum224, rawSubject string, getCert func() (*Certificate, error)) {
-	if getCert == nil {
-		panic("getCert can't be nil")
-	}
-
-	// Check that the certificate isn't being added twice.
-	if s.haveSum[rawSum224] {
-		return
-	}
-
-	s.haveSum[rawSum224] = true
-	s.lazyCerts = append(s.lazyCerts, lazyCert{
-		rawSubject: []byte(rawSubject),
-		getCert:    getCert,
-	})
-	s.byName[rawSubject] = append(s.byName[rawSubject], len(s.lazyCerts)-1)
-}
-
-// AppendCertsFromPEM attempts to parse a series of PEM encoded certificates.
-// It appends any certificates found to s and reports whether any certificates
-// were successfully parsed.
-//
-// On many Linux systems, /etc/ssl/cert.pem will contain the system wide set
-// of root CAs in a format suitable for this function.
-func (s *CertPool) AppendCertsFromPEM(pemCerts []byte) (ok bool) {
-	for len(pemCerts) > 0 {
-		var block *pem.Block
-		block, pemCerts = pem.Decode(pemCerts)
-		if block == nil {
-			break
-		}
-		if block.Type != "CERTIFICATE" || len(block.Headers) != 0 {
-			continue
-		}
-
-		certBytes := block.Bytes
-		cert, err := ParseCertificate(certBytes)
-		if err != nil {
-			continue
-		}
-		var lazyCert struct {
-			sync.Once
-			v *Certificate
-		}
-		s.addCertFunc(sha256.Sum224(cert.Raw), string(cert.RawSubject), func() (*Certificate, error) {
-			lazyCert.Do(func() {
-				// This can't fail, as the same bytes already parsed above.
-				lazyCert.v, _ = ParseCertificate(certBytes)
-				certBytes = nil
-			})
-			return lazyCert.v, nil
-		})
-		ok = true
-	}
-
-	return ok
-}
-
-// Subjects returns a list of the DER-encoded subjects of
-// all of the certificates in the pool.
-//
-// Deprecated: if s was returned by SystemCertPool, Subjects
-// will not include the system roots.
-func (s *CertPool) Subjects() [][]byte {
-	res := make([][]byte, s.len())
-	for i, lc := range s.lazyCerts {
-		res[i] = lc.rawSubject
-	}
-	return res
-}
diff --git a/contrib/go/_std_1.18/src/crypto/x509/internal/macos/corefoundation.go b/contrib/go/_std_1.18/src/crypto/x509/internal/macos/corefoundation.go
deleted file mode 100644
index 75c212910b..0000000000
--- a/contrib/go/_std_1.18/src/crypto/x509/internal/macos/corefoundation.go
+++ /dev/null
@@ -1,207 +0,0 @@
-// Copyright 2020 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build darwin
-
-// Package macOS provides cgo-less wrappers for Core Foundation and
-// Security.framework, similarly to how package syscall provides access to
-// libSystem.dylib.
-package macOS
-
-import (
-	"errors"
-	"internal/abi"
-	"reflect"
-	"runtime"
-	"time"
-	"unsafe"
-)
-
-// Core Foundation linker flags for the external linker. See Issue 42459.
-//go:cgo_ldflag "-framework"
-//go:cgo_ldflag "CoreFoundation"
-
-// CFRef is an opaque reference to a Core Foundation object. It is a pointer,
-// but to memory not owned by Go, so not an unsafe.Pointer.
-type CFRef uintptr
-
-// CFDataToSlice returns a copy of the contents of data as a bytes slice.
-func CFDataToSlice(data CFRef) []byte {
-	length := CFDataGetLength(data)
-	ptr := CFDataGetBytePtr(data)
-	src := (*[1 << 20]byte)(unsafe.Pointer(ptr))[:length:length]
-	out := make([]byte, length)
-	copy(out, src)
-	return out
-}
-
-// CFStringToString returns a Go string representation of the passed
-// in CFString.
-func CFStringToString(ref CFRef) string {
-	data := CFStringCreateExternalRepresentation(ref)
-	b := CFDataToSlice(data)
-	CFRelease(data)
-	return string(b)
-}
-
-// TimeToCFDateRef converts a time.Time into an apple CFDateRef
-func TimeToCFDateRef(t time.Time) CFRef {
-	secs := t.Sub(time.Date(2001, 1, 1, 0, 0, 0, 0, time.UTC)).Seconds()
-	ref := CFDateCreate(secs)
-	return ref
-}
-
-type CFString CFRef
-
-const kCFAllocatorDefault = 0
-const kCFStringEncodingUTF8 = 0x08000100
-
-//go:cgo_import_dynamic x509_CFDataCreate CFDataCreate "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
-
-func BytesToCFData(b []byte) CFRef {
-	p := unsafe.Pointer((*reflect.SliceHeader)(unsafe.Pointer(&b)).Data)
-	ret := syscall(abi.FuncPCABI0(x509_CFDataCreate_trampoline), kCFAllocatorDefault, uintptr(p), uintptr(len(b)), 0, 0, 0)
-	runtime.KeepAlive(p)
-	return CFRef(ret)
-}
-func x509_CFDataCreate_trampoline()
-
-//go:cgo_import_dynamic x509_CFStringCreateWithBytes CFStringCreateWithBytes "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
-
-// StringToCFString returns a copy of the UTF-8 contents of s as a new CFString.
-func StringToCFString(s string) CFString {
-	p := unsafe.Pointer((*reflect.StringHeader)(unsafe.Pointer(&s)).Data)
-	ret := syscall(abi.FuncPCABI0(x509_CFStringCreateWithBytes_trampoline), kCFAllocatorDefault, uintptr(p),
-		uintptr(len(s)), uintptr(kCFStringEncodingUTF8), 0 /* isExternalRepresentation */, 0)
-	runtime.KeepAlive(p)
-	return CFString(ret)
-}
-func x509_CFStringCreateWithBytes_trampoline()
-
-//go:cgo_import_dynamic x509_CFDictionaryGetValueIfPresent CFDictionaryGetValueIfPresent "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
-
-func CFDictionaryGetValueIfPresent(dict CFRef, key CFString) (value CFRef, ok bool) {
-	ret := syscall(abi.FuncPCABI0(x509_CFDictionaryGetValueIfPresent_trampoline), uintptr(dict), uintptr(key),
-		uintptr(unsafe.Pointer(&value)), 0, 0, 0)
-	if ret == 0 {
-		return 0, false
-	}
-	return value, true
-}
-func x509_CFDictionaryGetValueIfPresent_trampoline()
-
-const kCFNumberSInt32Type = 3
-
-//go:cgo_import_dynamic x509_CFNumberGetValue CFNumberGetValue "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
-
-func CFNumberGetValue(num CFRef) (int32, error) {
-	var value int32
-	ret := syscall(abi.FuncPCABI0(x509_CFNumberGetValue_trampoline), uintptr(num), uintptr(kCFNumberSInt32Type),
-		uintptr(unsafe.Pointer(&value)), 0, 0, 0)
-	if ret == 0 {
-		return 0, errors.New("CFNumberGetValue call failed")
-	}
-	return value, nil
-}
-func x509_CFNumberGetValue_trampoline()
-
-//go:cgo_import_dynamic x509_CFDataGetLength CFDataGetLength "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
-
-func CFDataGetLength(data CFRef) int {
-	ret := syscall(abi.FuncPCABI0(x509_CFDataGetLength_trampoline), uintptr(data), 0, 0, 0, 0, 0)
-	return int(ret)
-}
-func x509_CFDataGetLength_trampoline()
-
-//go:cgo_import_dynamic x509_CFDataGetBytePtr CFDataGetBytePtr "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
-
-func CFDataGetBytePtr(data CFRef) uintptr {
-	ret := syscall(abi.FuncPCABI0(x509_CFDataGetBytePtr_trampoline), uintptr(data), 0, 0, 0, 0, 0)
-	return ret
-}
-func x509_CFDataGetBytePtr_trampoline()
-
-//go:cgo_import_dynamic x509_CFArrayGetCount CFArrayGetCount "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
-
-func CFArrayGetCount(array CFRef) int {
-	ret := syscall(abi.FuncPCABI0(x509_CFArrayGetCount_trampoline), uintptr(array), 0, 0, 0, 0, 0)
-	return int(ret)
-}
-func x509_CFArrayGetCount_trampoline()
-
-//go:cgo_import_dynamic x509_CFArrayGetValueAtIndex CFArrayGetValueAtIndex "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
-
-func CFArrayGetValueAtIndex(array CFRef, index int) CFRef {
-	ret := syscall(abi.FuncPCABI0(x509_CFArrayGetValueAtIndex_trampoline), uintptr(array), uintptr(index), 0, 0, 0, 0)
-	return CFRef(ret)
-}
-func x509_CFArrayGetValueAtIndex_trampoline()
-
-//go:cgo_import_dynamic x509_CFEqual CFEqual "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
-
-func CFEqual(a, b CFRef) bool {
-	ret := syscall(abi.FuncPCABI0(x509_CFEqual_trampoline), uintptr(a), uintptr(b), 0, 0, 0, 0)
-	return ret == 1
-}
-func x509_CFEqual_trampoline()
-
-//go:cgo_import_dynamic x509_CFRelease CFRelease "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
-
-func CFRelease(ref CFRef) {
-	syscall(abi.FuncPCABI0(x509_CFRelease_trampoline), uintptr(ref), 0, 0, 0, 0, 0)
-}
-func x509_CFRelease_trampoline()
-
-//go:cgo_import_dynamic x509_CFArrayCreateMutable CFArrayCreateMutable "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
-
-func CFArrayCreateMutable() CFRef {
-	ret := syscall(abi.FuncPCABI0(x509_CFArrayCreateMutable_trampoline), kCFAllocatorDefault, 0, 0 /* kCFTypeArrayCallBacks */, 0, 0, 0)
-	return CFRef(ret)
-}
-func x509_CFArrayCreateMutable_trampoline()
-
-//go:cgo_import_dynamic x509_CFArrayAppendValue CFArrayAppendValue "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
-
-func CFArrayAppendValue(array CFRef, val CFRef) {
-	syscall(abi.FuncPCABI0(x509_CFArrayAppendValue_trampoline), uintptr(array), uintptr(val), 0, 0, 0, 0)
-}
-func x509_CFArrayAppendValue_trampoline()
-
-//go:cgo_import_dynamic x509_CFDateCreate CFDateCreate "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
-
-func CFDateCreate(seconds float64) CFRef {
-	ret := syscall(abi.FuncPCABI0(x509_CFDateCreate_trampoline), kCFAllocatorDefault, 0, 0, 0, 0, seconds)
-	return CFRef(ret)
-}
-func x509_CFDateCreate_trampoline()
-
-//go:cgo_import_dynamic x509_CFErrorCopyDescription CFErrorCopyDescription "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
-
-func CFErrorCopyDescription(errRef CFRef) CFRef {
-	ret := syscall(abi.FuncPCABI0(x509_CFErrorCopyDescription_trampoline), uintptr(errRef), 0, 0, 0, 0, 0)
-	return CFRef(ret)
-}
-func x509_CFErrorCopyDescription_trampoline()
-
-//go:cgo_import_dynamic x509_CFStringCreateExternalRepresentation CFStringCreateExternalRepresentation "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
-
-func CFStringCreateExternalRepresentation(strRef CFRef) CFRef {
-	ret := syscall(abi.FuncPCABI0(x509_CFStringCreateExternalRepresentation_trampoline), kCFAllocatorDefault, uintptr(strRef), kCFStringEncodingUTF8, 0, 0, 0)
-	return CFRef(ret)
-}
-func x509_CFStringCreateExternalRepresentation_trampoline()
-
-// syscall is implemented in the runtime package (runtime/sys_darwin.go)
-func syscall(fn, a1, a2, a3, a4, a5 uintptr, f1 float64) uintptr
-
-// ReleaseCFArray iterates through an array, releasing its contents, and then
-// releases the array itself. This is necessary because we cannot, easily, set the
-// CFArrayCallBacks argument when creating CFArrays.
-func ReleaseCFArray(array CFRef) {
-	for i := 0; i < CFArrayGetCount(array); i++ {
-		ref := CFArrayGetValueAtIndex(array, i)
-		CFRelease(ref)
-	}
-	CFRelease(array)
-}
diff --git a/contrib/go/_std_1.18/src/crypto/x509/internal/macos/security.go b/contrib/go/_std_1.18/src/crypto/x509/internal/macos/security.go
deleted file mode 100644
index ef64bda49f..0000000000
--- a/contrib/go/_std_1.18/src/crypto/x509/internal/macos/security.go
+++ /dev/null
@@ -1,234 +0,0 @@
-// Copyright 2020 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build darwin
-
-package macOS
-
-import (
-	"errors"
-	"fmt"
-	"internal/abi"
-	"strconv"
-	"unsafe"
-)
-
-// Security.framework linker flags for the external linker. See Issue 42459.
-//go:cgo_ldflag "-framework"
-//go:cgo_ldflag "Security"
-
-// Based on https://opensource.apple.com/source/Security/Security-59306.41.2/base/Security.h
-
-type SecTrustSettingsResult int32
-
-const (
-	SecTrustSettingsResultInvalid SecTrustSettingsResult = iota
-	SecTrustSettingsResultTrustRoot
-	SecTrustSettingsResultTrustAsRoot
-	SecTrustSettingsResultDeny
-	SecTrustSettingsResultUnspecified
-)
-
-type SecTrustResultType int32
-
-const (
-	SecTrustResultInvalid SecTrustResultType = iota
-	SecTrustResultProceed
-	SecTrustResultConfirm // deprecated
-	SecTrustResultDeny
-	SecTrustResultUnspecified
-	SecTrustResultRecoverableTrustFailure
-	SecTrustResultFatalTrustFailure
-	SecTrustResultOtherError
-)
-
-type SecTrustSettingsDomain int32
-
-const (
-	SecTrustSettingsDomainUser SecTrustSettingsDomain = iota
-	SecTrustSettingsDomainAdmin
-	SecTrustSettingsDomainSystem
-)
-
-type OSStatus struct {
-	call   string
-	status int32
-}
-
-func (s OSStatus) Error() string {
-	return s.call + " error: " + strconv.Itoa(int(s.status))
-}
-
-// Dictionary keys are defined as build-time strings with CFSTR, but the Go
-// linker's internal linking mode can't handle CFSTR relocations. Create our
-// own dynamic strings instead and just never release them.
-//
-// Note that this might be the only thing that can break over time if
-// these values change, as the ABI arguably requires using the strings
-// pointed to by the symbols, not values that happen to be equal to them.
-
-var SecTrustSettingsResultKey = StringToCFString("kSecTrustSettingsResult")
-var SecTrustSettingsPolicy = StringToCFString("kSecTrustSettingsPolicy")
-var SecTrustSettingsPolicyString = StringToCFString("kSecTrustSettingsPolicyString")
-var SecPolicyOid = StringToCFString("SecPolicyOid")
-var SecPolicyAppleSSL = StringToCFString("1.2.840.113635.100.1.3") // defined by POLICYMACRO
-
-var ErrNoTrustSettings = errors.New("no trust settings found")
-
-const errSecNoTrustSettings = -25263
-
-//go:cgo_import_dynamic x509_SecTrustSettingsCopyCertificates SecTrustSettingsCopyCertificates "/System/Library/Frameworks/Security.framework/Versions/A/Security"
-
-func SecTrustSettingsCopyCertificates(domain SecTrustSettingsDomain) (certArray CFRef, err error) {
-	ret := syscall(abi.FuncPCABI0(x509_SecTrustSettingsCopyCertificates_trampoline), uintptr(domain),
-		uintptr(unsafe.Pointer(&certArray)), 0, 0, 0, 0)
-	if int32(ret) == errSecNoTrustSettings {
-		return 0, ErrNoTrustSettings
-	} else if ret != 0 {
-		return 0, OSStatus{"SecTrustSettingsCopyCertificates", int32(ret)}
-	}
-	return certArray, nil
-}
-func x509_SecTrustSettingsCopyCertificates_trampoline()
-
-const errSecItemNotFound = -25300
-
-//go:cgo_import_dynamic x509_SecTrustSettingsCopyTrustSettings SecTrustSettingsCopyTrustSettings "/System/Library/Frameworks/Security.framework/Versions/A/Security"
-
-func SecTrustSettingsCopyTrustSettings(cert CFRef, domain SecTrustSettingsDomain) (trustSettings CFRef, err error) {
-	ret := syscall(abi.FuncPCABI0(x509_SecTrustSettingsCopyTrustSettings_trampoline), uintptr(cert), uintptr(domain),
-		uintptr(unsafe.Pointer(&trustSettings)), 0, 0, 0)
-	if int32(ret) == errSecItemNotFound {
-		return 0, ErrNoTrustSettings
-	} else if ret != 0 {
-		return 0, OSStatus{"SecTrustSettingsCopyTrustSettings", int32(ret)}
-	}
-	return trustSettings, nil
-}
-func x509_SecTrustSettingsCopyTrustSettings_trampoline()
-
-//go:cgo_import_dynamic x509_SecPolicyCopyProperties SecPolicyCopyProperties "/System/Library/Frameworks/Security.framework/Versions/A/Security"
-
-func SecPolicyCopyProperties(policy CFRef) CFRef {
-	ret := syscall(abi.FuncPCABI0(x509_SecPolicyCopyProperties_trampoline), uintptr(policy), 0, 0, 0, 0, 0)
-	return CFRef(ret)
-}
-func x509_SecPolicyCopyProperties_trampoline()
-
-//go:cgo_import_dynamic x509_SecTrustCreateWithCertificates SecTrustCreateWithCertificates "/System/Library/Frameworks/Security.framework/Versions/A/Security"
-
-func SecTrustCreateWithCertificates(certs CFRef, policies CFRef) (CFRef, error) {
-	var trustObj CFRef
-	ret := syscall(abi.FuncPCABI0(x509_SecTrustCreateWithCertificates_trampoline), uintptr(certs), uintptr(policies),
-		uintptr(unsafe.Pointer(&trustObj)), 0, 0, 0)
-	if int32(ret) != 0 {
-		return 0, OSStatus{"SecTrustCreateWithCertificates", int32(ret)}
-	}
-	return trustObj, nil
-}
-func x509_SecTrustCreateWithCertificates_trampoline()
-
-//go:cgo_import_dynamic x509_SecCertificateCreateWithData SecCertificateCreateWithData "/System/Library/Frameworks/Security.framework/Versions/A/Security"
-
-func SecCertificateCreateWithData(b []byte) CFRef {
-	data := BytesToCFData(b)
-	ret := syscall(abi.FuncPCABI0(x509_SecCertificateCreateWithData_trampoline), kCFAllocatorDefault, uintptr(data), 0, 0, 0, 0)
-	CFRelease(data)
-	return CFRef(ret)
-}
-func x509_SecCertificateCreateWithData_trampoline()
-
-//go:cgo_import_dynamic x509_SecPolicyCreateSSL SecPolicyCreateSSL "/System/Library/Frameworks/Security.framework/Versions/A/Security"
-
-func SecPolicyCreateSSL(name string) CFRef {
-	var hostname CFString
-	if name != "" {
-		hostname = StringToCFString(name)
-		defer CFRelease(CFRef(hostname))
-	}
-	ret := syscall(abi.FuncPCABI0(x509_SecPolicyCreateSSL_trampoline), 1 /* true */, uintptr(hostname), 0, 0, 0, 0)
-	return CFRef(ret)
-}
-func x509_SecPolicyCreateSSL_trampoline()
-
-//go:cgo_import_dynamic x509_SecTrustSetVerifyDate SecTrustSetVerifyDate "/System/Library/Frameworks/Security.framework/Versions/A/Security"
-
-func SecTrustSetVerifyDate(trustObj CFRef, dateRef CFRef) error {
-	ret := syscall(abi.FuncPCABI0(x509_SecTrustSetVerifyDate_trampoline), uintptr(trustObj), uintptr(dateRef), 0, 0, 0, 0)
-	if int32(ret) != 0 {
-		return OSStatus{"SecTrustSetVerifyDate", int32(ret)}
-	}
-	return nil
-}
-func x509_SecTrustSetVerifyDate_trampoline()
-
-//go:cgo_import_dynamic x509_SecTrustEvaluate SecTrustEvaluate "/System/Library/Frameworks/Security.framework/Versions/A/Security"
-
-func SecTrustEvaluate(trustObj CFRef) (CFRef, error) {
-	var result CFRef
-	ret := syscall(abi.FuncPCABI0(x509_SecTrustEvaluate_trampoline), uintptr(trustObj), uintptr(unsafe.Pointer(&result)), 0, 0, 0, 0)
-	if int32(ret) != 0 {
-		return 0, OSStatus{"SecTrustEvaluate", int32(ret)}
-	}
-	return CFRef(result), nil
-}
-func x509_SecTrustEvaluate_trampoline()
-
-//go:cgo_import_dynamic x509_SecTrustGetResult SecTrustGetResult "/System/Library/Frameworks/Security.framework/Versions/A/Security"
-
-func SecTrustGetResult(trustObj CFRef, result CFRef) (CFRef, CFRef, error) {
-	var chain, info CFRef
-	ret := syscall(abi.FuncPCABI0(x509_SecTrustGetResult_trampoline), uintptr(trustObj), uintptr(unsafe.Pointer(&result)),
-		uintptr(unsafe.Pointer(&chain)), uintptr(unsafe.Pointer(&info)), 0, 0)
-	if int32(ret) != 0 {
-		return 0, 0, OSStatus{"SecTrustGetResult", int32(ret)}
-	}
-	return chain, info, nil
-}
-func x509_SecTrustGetResult_trampoline()
-
-//go:cgo_import_dynamic x509_SecTrustEvaluateWithError SecTrustEvaluateWithError "/System/Library/Frameworks/Security.framework/Versions/A/Security"
-
-func SecTrustEvaluateWithError(trustObj CFRef) error {
-	var errRef CFRef
-	ret := syscall(abi.FuncPCABI0(x509_SecTrustEvaluateWithError_trampoline), uintptr(trustObj), uintptr(unsafe.Pointer(&errRef)), 0, 0, 0, 0)
-	if int32(ret) != 1 {
-		errStr := CFErrorCopyDescription(errRef)
-		err := fmt.Errorf("x509: %s", CFStringToString(errStr))
-		CFRelease(errRef)
-		CFRelease(errStr)
-		return err
-	}
-	return nil
-}
-func x509_SecTrustEvaluateWithError_trampoline()
-
-//go:cgo_import_dynamic x509_SecTrustGetCertificateCount SecTrustGetCertificateCount "/System/Library/Frameworks/Security.framework/Versions/A/Security"
-
-func SecTrustGetCertificateCount(trustObj CFRef) int {
-	ret := syscall(abi.FuncPCABI0(x509_SecTrustGetCertificateCount_trampoline), uintptr(trustObj), 0, 0, 0, 0, 0)
-	return int(ret)
-}
-func x509_SecTrustGetCertificateCount_trampoline()
-
-//go:cgo_import_dynamic x509_SecTrustGetCertificateAtIndex SecTrustGetCertificateAtIndex "/System/Library/Frameworks/Security.framework/Versions/A/Security"
-
-func SecTrustGetCertificateAtIndex(trustObj CFRef, i int) CFRef {
-	ret := syscall(abi.FuncPCABI0(x509_SecTrustGetCertificateAtIndex_trampoline), uintptr(trustObj), uintptr(i), 0, 0, 0, 0)
-	return CFRef(ret)
-}
-func x509_SecTrustGetCertificateAtIndex_trampoline()
-
-//go:cgo_import_dynamic x509_SecCertificateCopyData SecCertificateCopyData "/System/Library/Frameworks/Security.framework/Versions/A/Security"
-
-func SecCertificateCopyData(cert CFRef) ([]byte, error) {
-	ret := syscall(abi.FuncPCABI0(x509_SecCertificateCopyData_trampoline), uintptr(cert), 0, 0, 0, 0, 0)
-	if ret == 0 {
-		return nil, errors.New("x509: invalid certificate object")
-	}
-	b := CFDataToSlice(CFRef(ret))
-	CFRelease(CFRef(ret))
-	return b, nil
-}
-func x509_SecCertificateCopyData_trampoline()
diff --git a/contrib/go/_std_1.18/src/crypto/x509/parser.go b/contrib/go/_std_1.18/src/crypto/x509/parser.go
deleted file mode 100644
index 2cb1ad2d7f..0000000000
--- a/contrib/go/_std_1.18/src/crypto/x509/parser.go
+++ /dev/null
@@ -1,1013 +0,0 @@
-// Copyright 2021 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-package x509
-
-import (
-	"bytes"
-	"crypto/dsa"
-	"crypto/ecdsa"
-	"crypto/ed25519"
-	"crypto/elliptic"
-	"crypto/rsa"
-	"crypto/x509/pkix"
-	"encoding/asn1"
-	"errors"
-	"fmt"
-	"math/big"
-	"net"
-	"net/url"
-	"strconv"
-	"strings"
-	"time"
-	"unicode/utf16"
-	"unicode/utf8"
-
-	"golang.org/x/crypto/cryptobyte"
-	cryptobyte_asn1 "golang.org/x/crypto/cryptobyte/asn1"
-)
-
-// isPrintable reports whether the given b is in the ASN.1 PrintableString set.
-// This is a simplified version of encoding/asn1.isPrintable.
-func isPrintable(b byte) bool {
-	return 'a' <= b && b <= 'z' ||
-		'A' <= b && b <= 'Z' ||
-		'0' <= b && b <= '9' ||
-		'\'' <= b && b <= ')' ||
-		'+' <= b && b <= '/' ||
-		b == ' ' ||
-		b == ':' ||
-		b == '=' ||
-		b == '?' ||
-		// This is technically not allowed in a PrintableString.
-		// However, x509 certificates with wildcard strings don't
-		// always use the correct string type so we permit it.
-		b == '*' ||
-		// This is not technically allowed either. However, not
-		// only is it relatively common, but there are also a
-		// handful of CA certificates that contain it. At least
-		// one of which will not expire until 2027.
-		b == '&'
-}
-
-// parseASN1String parses the ASN.1 string types T61String, PrintableString,
-// UTF8String, BMPString, IA5String, and NumericString. This is mostly copied
-// from the respective encoding/asn1.parse... methods, rather than just
-// increasing the API surface of that package.
-func parseASN1String(tag cryptobyte_asn1.Tag, value []byte) (string, error) {
-	switch tag {
-	case cryptobyte_asn1.T61String:
-		return string(value), nil
-	case cryptobyte_asn1.PrintableString:
-		for _, b := range value {
-			if !isPrintable(b) {
-				return "", errors.New("invalid PrintableString")
-			}
-		}
-		return string(value), nil
-	case cryptobyte_asn1.UTF8String:
-		if !utf8.Valid(value) {
-			return "", errors.New("invalid UTF-8 string")
-		}
-		return string(value), nil
-	case cryptobyte_asn1.Tag(asn1.TagBMPString):
-		if len(value)%2 != 0 {
-			return "", errors.New("invalid BMPString")
-		}
-
-		// Strip terminator if present.
-		if l := len(value); l >= 2 && value[l-1] == 0 && value[l-2] == 0 {
-			value = value[:l-2]
-		}
-
-		s := make([]uint16, 0, len(value)/2)
-		for len(value) > 0 {
-			s = append(s, uint16(value[0])<<8+uint16(value[1]))
-			value = value[2:]
-		}
-
-		return string(utf16.Decode(s)), nil
-	case cryptobyte_asn1.IA5String:
-		s := string(value)
-		if isIA5String(s) != nil {
-			return "", errors.New("invalid IA5String")
-		}
-		return s, nil
-	case cryptobyte_asn1.Tag(asn1.TagNumericString):
-		for _, b := range value {
-			if !('0' <= b && b <= '9' || b == ' ') {
-				return "", errors.New("invalid NumericString")
-			}
-		}
-		return string(value), nil
-	}
-	return "", fmt.Errorf("unsupported string type: %v", tag)
-}
-
-// parseName parses a DER encoded Name as defined in RFC 5280. We may
-// want to export this function in the future for use in crypto/tls.
-func parseName(raw cryptobyte.String) (*pkix.RDNSequence, error) {
-	if !raw.ReadASN1(&raw, cryptobyte_asn1.SEQUENCE) {
-		return nil, errors.New("x509: invalid RDNSequence")
-	}
-
-	var rdnSeq pkix.RDNSequence
-	for !raw.Empty() {
-		var rdnSet pkix.RelativeDistinguishedNameSET
-		var set cryptobyte.String
-		if !raw.ReadASN1(&set, cryptobyte_asn1.SET) {
-			return nil, errors.New("x509: invalid RDNSequence")
-		}
-		for !set.Empty() {
-			var atav cryptobyte.String
-			if !set.ReadASN1(&atav, cryptobyte_asn1.SEQUENCE) {
-				return nil, errors.New("x509: invalid RDNSequence: invalid attribute")
-			}
-			var attr pkix.AttributeTypeAndValue
-			if !atav.ReadASN1ObjectIdentifier(&attr.Type) {
-				return nil, errors.New("x509: invalid RDNSequence: invalid attribute type")
-			}
-			var rawValue cryptobyte.String
-			var valueTag cryptobyte_asn1.Tag
-			if !atav.ReadAnyASN1(&rawValue, &valueTag) {
-				return nil, errors.New("x509: invalid RDNSequence: invalid attribute value")
-			}
-			var err error
-			attr.Value, err = parseASN1String(valueTag, rawValue)
-			if err != nil {
-				return nil, fmt.Errorf("x509: invalid RDNSequence: invalid attribute value: %s", err)
-			}
-			rdnSet = append(rdnSet, attr)
-		}
-
-		rdnSeq = append(rdnSeq, rdnSet)
-	}
-
-	return &rdnSeq, nil
-}
-
-func parseAI(der cryptobyte.String) (pkix.AlgorithmIdentifier, error) {
-	ai := pkix.AlgorithmIdentifier{}
-	if !der.ReadASN1ObjectIdentifier(&ai.Algorithm) {
-		return ai, errors.New("x509: malformed OID")
-	}
-	if der.Empty() {
-		return ai, nil
-	}
-	var params cryptobyte.String
-	var tag cryptobyte_asn1.Tag
-	if !der.ReadAnyASN1Element(&params, &tag) {
-		return ai, errors.New("x509: malformed parameters")
-	}
-	ai.Parameters.Tag = int(tag)
-	ai.Parameters.FullBytes = params
-	return ai, nil
-}
-
-func parseValidity(der cryptobyte.String) (time.Time, time.Time, error) {
-	extract := func() (time.Time, error) {
-		var t time.Time
-		switch {
-		case der.PeekASN1Tag(cryptobyte_asn1.UTCTime):
-			// TODO(rolandshoemaker): once #45411 is fixed, the following code
-			// should be replaced with a call to der.ReadASN1UTCTime.
-			var utc cryptobyte.String
-			if !der.ReadASN1(&utc, cryptobyte_asn1.UTCTime) {
-				return t, errors.New("x509: malformed UTCTime")
-			}
-			s := string(utc)
-
-			formatStr := "0601021504Z0700"
-			var err error
-			t, err = time.Parse(formatStr, s)
-			if err != nil {
-				formatStr = "060102150405Z0700"
-				t, err = time.Parse(formatStr, s)
-			}
-			if err != nil {
-				return t, err
-			}
-
-			if serialized := t.Format(formatStr); serialized != s {
-				return t, errors.New("x509: malformed UTCTime")
-			}
-
-			if t.Year() >= 2050 {
-				// UTCTime only encodes times prior to 2050. See https://tools.ietf.org/html/rfc5280#section-4.1.2.5.1
-				t = t.AddDate(-100, 0, 0)
-			}
-		case der.PeekASN1Tag(cryptobyte_asn1.GeneralizedTime):
-			if !der.ReadASN1GeneralizedTime(&t) {
-				return t, errors.New("x509: malformed GeneralizedTime")
-			}
-		default:
-			return t, errors.New("x509: unsupported time format")
-		}
-		return t, nil
-	}
-
-	notBefore, err := extract()
-	if err != nil {
-		return time.Time{}, time.Time{}, err
-	}
-	notAfter, err := extract()
-	if err != nil {
-		return time.Time{}, time.Time{}, err
-	}
-
-	return notBefore, notAfter, nil
-}
-
-func parseExtension(der cryptobyte.String) (pkix.Extension, error) {
-	var ext pkix.Extension
-	if !der.ReadASN1ObjectIdentifier(&ext.Id) {
-		return ext, errors.New("x509: malformed extension OID field")
-	}
-	if der.PeekASN1Tag(cryptobyte_asn1.BOOLEAN) {
-		if !der.ReadASN1Boolean(&ext.Critical) {
-			return ext, errors.New("x509: malformed extension critical field")
-		}
-	}
-	var val cryptobyte.String
-	if !der.ReadASN1(&val, cryptobyte_asn1.OCTET_STRING) {
-		return ext, errors.New("x509: malformed extension value field")
-	}
-	ext.Value = val
-	return ext, nil
-}
-
-func parsePublicKey(algo PublicKeyAlgorithm, keyData *publicKeyInfo) (any, error) {
-	der := cryptobyte.String(keyData.PublicKey.RightAlign())
-	switch algo {
-	case RSA:
-		// RSA public keys must have a NULL in the parameters.
-		// See RFC 3279, Section 2.3.1.
-		if !bytes.Equal(keyData.Algorithm.Parameters.FullBytes, asn1.NullBytes) {
-			return nil, errors.New("x509: RSA key missing NULL parameters")
-		}
-
-		p := &pkcs1PublicKey{N: new(big.Int)}
-		if !der.ReadASN1(&der, cryptobyte_asn1.SEQUENCE) {
-			return nil, errors.New("x509: invalid RSA public key")
-		}
-		if !der.ReadASN1Integer(p.N) {
-			return nil, errors.New("x509: invalid RSA modulus")
-		}
-		if !der.ReadASN1Integer(&p.E) {
-			return nil, errors.New("x509: invalid RSA public exponent")
-		}
-
-		if p.N.Sign() <= 0 {
-			return nil, errors.New("x509: RSA modulus is not a positive number")
-		}
-		if p.E <= 0 {
-			return nil, errors.New("x509: RSA public exponent is not a positive number")
-		}
-
-		pub := &rsa.PublicKey{
-			E: p.E,
-			N: p.N,
-		}
-		return pub, nil
-	case ECDSA:
-		paramsDer := cryptobyte.String(keyData.Algorithm.Parameters.FullBytes)
-		namedCurveOID := new(asn1.ObjectIdentifier)
-		if !paramsDer.ReadASN1ObjectIdentifier(namedCurveOID) {
-			return nil, errors.New("x509: invalid ECDSA parameters")
-		}
-		namedCurve := namedCurveFromOID(*namedCurveOID)
-		if namedCurve == nil {
-			return nil, errors.New("x509: unsupported elliptic curve")
-		}
-		x, y := elliptic.Unmarshal(namedCurve, der)
-		if x == nil {
-			return nil, errors.New("x509: failed to unmarshal elliptic curve point")
-		}
-		pub := &ecdsa.PublicKey{
-			Curve: namedCurve,
-			X:     x,
-			Y:     y,
-		}
-		return pub, nil
-	case Ed25519:
-		// RFC 8410, Section 3
-		// > For all of the OIDs, the parameters MUST be absent.
-		if len(keyData.Algorithm.Parameters.FullBytes) != 0 {
-			return nil, errors.New("x509: Ed25519 key encoded with illegal parameters")
-		}
-		if len(der) != ed25519.PublicKeySize {
-			return nil, errors.New("x509: wrong Ed25519 public key size")
-		}
-		return ed25519.PublicKey(der), nil
-	case DSA:
-		y := new(big.Int)
-		if !der.ReadASN1Integer(y) {
-			return nil, errors.New("x509: invalid DSA public key")
-		}
-		pub := &dsa.PublicKey{
-			Y: y,
-			Parameters: dsa.Parameters{
-				P: new(big.Int),
-				Q: new(big.Int),
-				G: new(big.Int),
-			},
-		}
-		paramsDer := cryptobyte.String(keyData.Algorithm.Parameters.FullBytes)
-		if !paramsDer.ReadASN1(&paramsDer, cryptobyte_asn1.SEQUENCE) ||
-			!paramsDer.ReadASN1Integer(pub.Parameters.P) ||
-			!paramsDer.ReadASN1Integer(pub.Parameters.Q) ||
-			!paramsDer.ReadASN1Integer(pub.Parameters.G) {
-			return nil, errors.New("x509: invalid DSA parameters")
-		}
-		if pub.Y.Sign() <= 0 || pub.Parameters.P.Sign() <= 0 ||
-			pub.Parameters.Q.Sign() <= 0 || pub.Parameters.G.Sign() <= 0 {
-			return nil, errors.New("x509: zero or negative DSA parameter")
-		}
-		return pub, nil
-	default:
-		return nil, nil
-	}
-}
-
-func parseKeyUsageExtension(der cryptobyte.String) (KeyUsage, error) {
-	var usageBits asn1.BitString
-	if !der.ReadASN1BitString(&usageBits) {
-		return 0, errors.New("x509: invalid key usage")
-	}
-
-	var usage int
-	for i := 0; i < 9; i++ {
-		if usageBits.At(i) != 0 {
-			usage |= 1 << uint(i)
-		}
-	}
-	return KeyUsage(usage), nil
-}
-
-func parseBasicConstraintsExtension(der cryptobyte.String) (bool, int, error) {
-	var isCA bool
-	if !der.ReadASN1(&der, cryptobyte_asn1.SEQUENCE) {
-		return false, 0, errors.New("x509: invalid basic constraints a")
-	}
-	if der.PeekASN1Tag(cryptobyte_asn1.BOOLEAN) {
-		if !der.ReadASN1Boolean(&isCA) {
-			return false, 0, errors.New("x509: invalid basic constraints b")
-		}
-	}
-	maxPathLen := -1
-	if !der.Empty() && der.PeekASN1Tag(cryptobyte_asn1.INTEGER) {
-		if !der.ReadASN1Integer(&maxPathLen) {
-			return false, 0, errors.New("x509: invalid basic constraints c")
-		}
-	}
-
-	// TODO: map out.MaxPathLen to 0 if it has the -1 default value? (Issue 19285)
-	return isCA, maxPathLen, nil
-}
-
-func forEachSAN(der cryptobyte.String, callback func(tag int, data []byte) error) error {
-	if !der.ReadASN1(&der, cryptobyte_asn1.SEQUENCE) {
-		return errors.New("x509: invalid subject alternative names")
-	}
-	for !der.Empty() {
-		var san cryptobyte.String
-		var tag cryptobyte_asn1.Tag
-		if !der.ReadAnyASN1(&san, &tag) {
-			return errors.New("x509: invalid subject alternative name")
-		}
-		if err := callback(int(tag^0x80), san); err != nil {
-			return err
-		}
-	}
-
-	return nil
-}
-
-func parseSANExtension(der cryptobyte.String) (dnsNames, emailAddresses []string, ipAddresses []net.IP, uris []*url.URL, err error) {
-	err = forEachSAN(der, func(tag int, data []byte) error {
-		switch tag {
-		case nameTypeEmail:
-			email := string(data)
-			if err := isIA5String(email); err != nil {
-				return errors.New("x509: SAN rfc822Name is malformed")
-			}
-			emailAddresses = append(emailAddresses, email)
-		case nameTypeDNS:
-			name := string(data)
-			if err := isIA5String(name); err != nil {
-				return errors.New("x509: SAN dNSName is malformed")
-			}
-			dnsNames = append(dnsNames, string(name))
-		case nameTypeURI:
-			uriStr := string(data)
-			if err := isIA5String(uriStr); err != nil {
-				return errors.New("x509: SAN uniformResourceIdentifier is malformed")
-			}
-			uri, err := url.Parse(uriStr)
-			if err != nil {
-				return fmt.Errorf("x509: cannot parse URI %q: %s", uriStr, err)
-			}
-			if len(uri.Host) > 0 {
-				if _, ok := domainToReverseLabels(uri.Host); !ok {
-					return fmt.Errorf("x509: cannot parse URI %q: invalid domain", uriStr)
-				}
-			}
-			uris = append(uris, uri)
-		case nameTypeIP:
-			switch len(data) {
-			case net.IPv4len, net.IPv6len:
-				ipAddresses = append(ipAddresses, data)
-			default:
-				return errors.New("x509: cannot parse IP address of length " + strconv.Itoa(len(data)))
-			}
-		}
-
-		return nil
-	})
-
-	return
-}
-
-func parseExtKeyUsageExtension(der cryptobyte.String) ([]ExtKeyUsage, []asn1.ObjectIdentifier, error) {
-	var extKeyUsages []ExtKeyUsage
-	var unknownUsages []asn1.ObjectIdentifier
-	if !der.ReadASN1(&der, cryptobyte_asn1.SEQUENCE) {
-		return nil, nil, errors.New("x509: invalid extended key usages")
-	}
-	for !der.Empty() {
-		var eku asn1.ObjectIdentifier
-		if !der.ReadASN1ObjectIdentifier(&eku) {
-			return nil, nil, errors.New("x509: invalid extended key usages")
-		}
-		if extKeyUsage, ok := extKeyUsageFromOID(eku); ok {
-			extKeyUsages = append(extKeyUsages, extKeyUsage)
-		} else {
-			unknownUsages = append(unknownUsages, eku)
-		}
-	}
-	return extKeyUsages, unknownUsages, nil
-}
-
-func parseCertificatePoliciesExtension(der cryptobyte.String) ([]asn1.ObjectIdentifier, error) {
-	var oids []asn1.ObjectIdentifier
-	if !der.ReadASN1(&der, cryptobyte_asn1.SEQUENCE) {
-		return nil, errors.New("x509: invalid certificate policies")
-	}
-	for !der.Empty() {
-		var cp cryptobyte.String
-		if !der.ReadASN1(&cp, cryptobyte_asn1.SEQUENCE) {
-			return nil, errors.New("x509: invalid certificate policies")
-		}
-		var oid asn1.ObjectIdentifier
-		if !cp.ReadASN1ObjectIdentifier(&oid) {
-			return nil, errors.New("x509: invalid certificate policies")
-		}
-		oids = append(oids, oid)
-	}
-
-	return oids, nil
-}
-
-// isValidIPMask reports whether mask consists of zero or more 1 bits, followed by zero bits.
-func isValidIPMask(mask []byte) bool {
-	seenZero := false
-
-	for _, b := range mask {
-		if seenZero {
-			if b != 0 {
-				return false
-			}
-
-			continue
-		}
-
-		switch b {
-		case 0x00, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe:
-			seenZero = true
-		case 0xff:
-		default:
-			return false
-		}
-	}
-
-	return true
-}
-
-func parseNameConstraintsExtension(out *Certificate, e pkix.Extension) (unhandled bool, err error) {
-	// RFC 5280, 4.2.1.10
-
-	// NameConstraints ::= SEQUENCE {
-	//      permittedSubtrees       [0]     GeneralSubtrees OPTIONAL,
-	//      excludedSubtrees        [1]     GeneralSubtrees OPTIONAL }
-	//
-	// GeneralSubtrees ::= SEQUENCE SIZE (1..MAX) OF GeneralSubtree
-	//
-	// GeneralSubtree ::= SEQUENCE {
-	//      base                    GeneralName,
-	//      minimum         [0]     BaseDistance DEFAULT 0,
-	//      maximum         [1]     BaseDistance OPTIONAL }
-	//
-	// BaseDistance ::= INTEGER (0..MAX)
-
-	outer := cryptobyte.String(e.Value)
-	var toplevel, permitted, excluded cryptobyte.String
-	var havePermitted, haveExcluded bool
-	if !outer.ReadASN1(&toplevel, cryptobyte_asn1.SEQUENCE) ||
-		!outer.Empty() ||
-		!toplevel.ReadOptionalASN1(&permitted, &havePermitted, cryptobyte_asn1.Tag(0).ContextSpecific().Constructed()) ||
-		!toplevel.ReadOptionalASN1(&excluded, &haveExcluded, cryptobyte_asn1.Tag(1).ContextSpecific().Constructed()) ||
-		!toplevel.Empty() {
-		return false, errors.New("x509: invalid NameConstraints extension")
-	}
-
-	if !havePermitted && !haveExcluded || len(permitted) == 0 && len(excluded) == 0 {
-		// From RFC 5280, Section 4.2.1.10:
-		//   “either the permittedSubtrees field
-		//   or the excludedSubtrees MUST be
-		//   present”
-		return false, errors.New("x509: empty name constraints extension")
-	}
-
-	getValues := func(subtrees cryptobyte.String) (dnsNames []string, ips []*net.IPNet, emails, uriDomains []string, err error) {
-		for !subtrees.Empty() {
-			var seq, value cryptobyte.String
-			var tag cryptobyte_asn1.Tag
-			if !subtrees.ReadASN1(&seq, cryptobyte_asn1.SEQUENCE) ||
-				!seq.ReadAnyASN1(&value, &tag) {
-				return nil, nil, nil, nil, fmt.Errorf("x509: invalid NameConstraints extension")
-			}
-
-			var (
-				dnsTag   = cryptobyte_asn1.Tag(2).ContextSpecific()
-				emailTag = cryptobyte_asn1.Tag(1).ContextSpecific()
-				ipTag    = cryptobyte_asn1.Tag(7).ContextSpecific()
-				uriTag   = cryptobyte_asn1.Tag(6).ContextSpecific()
-			)
-
-			switch tag {
-			case dnsTag:
-				domain := string(value)
-				if err := isIA5String(domain); err != nil {
-					return nil, nil, nil, nil, errors.New("x509: invalid constraint value: " + err.Error())
-				}
-
-				trimmedDomain := domain
-				if len(trimmedDomain) > 0 && trimmedDomain[0] == '.' {
-					// constraints can have a leading
-					// period to exclude the domain
-					// itself, but that's not valid in a
-					// normal domain name.
-					trimmedDomain = trimmedDomain[1:]
-				}
-				if _, ok := domainToReverseLabels(trimmedDomain); !ok {
-					return nil, nil, nil, nil, fmt.Errorf("x509: failed to parse dnsName constraint %q", domain)
-				}
-				dnsNames = append(dnsNames, domain)
-
-			case ipTag:
-				l := len(value)
-				var ip, mask []byte
-
-				switch l {
-				case 8:
-					ip = value[:4]
-					mask = value[4:]
-
-				case 32:
-					ip = value[:16]
-					mask = value[16:]
-
-				default:
-					return nil, nil, nil, nil, fmt.Errorf("x509: IP constraint contained value of length %d", l)
-				}
-
-				if !isValidIPMask(mask) {
-					return nil, nil, nil, nil, fmt.Errorf("x509: IP constraint contained invalid mask %x", mask)
-				}
-
-				ips = append(ips, &net.IPNet{IP: net.IP(ip), Mask: net.IPMask(mask)})
-
-			case emailTag:
-				constraint := string(value)
-				if err := isIA5String(constraint); err != nil {
-					return nil, nil, nil, nil, errors.New("x509: invalid constraint value: " + err.Error())
-				}
-
-				// If the constraint contains an @ then
-				// it specifies an exact mailbox name.
-				if strings.Contains(constraint, "@") {
-					if _, ok := parseRFC2821Mailbox(constraint); !ok {
-						return nil, nil, nil, nil, fmt.Errorf("x509: failed to parse rfc822Name constraint %q", constraint)
-					}
-				} else {
-					// Otherwise it's a domain name.
-					domain := constraint
-					if len(domain) > 0 && domain[0] == '.' {
-						domain = domain[1:]
-					}
-					if _, ok := domainToReverseLabels(domain); !ok {
-						return nil, nil, nil, nil, fmt.Errorf("x509: failed to parse rfc822Name constraint %q", constraint)
-					}
-				}
-				emails = append(emails, constraint)
-
-			case uriTag:
-				domain := string(value)
-				if err := isIA5String(domain); err != nil {
-					return nil, nil, nil, nil, errors.New("x509: invalid constraint value: " + err.Error())
-				}
-
-				if net.ParseIP(domain) != nil {
-					return nil, nil, nil, nil, fmt.Errorf("x509: failed to parse URI constraint %q: cannot be IP address", domain)
-				}
-
-				trimmedDomain := domain
-				if len(trimmedDomain) > 0 && trimmedDomain[0] == '.' {
-					// constraints can have a leading
-					// period to exclude the domain itself,
-					// but that's not valid in a normal
-					// domain name.
-					trimmedDomain = trimmedDomain[1:]
-				}
-				if _, ok := domainToReverseLabels(trimmedDomain); !ok {
-					return nil, nil, nil, nil, fmt.Errorf("x509: failed to parse URI constraint %q", domain)
-				}
-				uriDomains = append(uriDomains, domain)
-
-			default:
-				unhandled = true
-			}
-		}
-
-		return dnsNames, ips, emails, uriDomains, nil
-	}
-
-	if out.PermittedDNSDomains, out.PermittedIPRanges, out.PermittedEmailAddresses, out.PermittedURIDomains, err = getValues(permitted); err != nil {
-		return false, err
-	}
-	if out.ExcludedDNSDomains, out.ExcludedIPRanges, out.ExcludedEmailAddresses, out.ExcludedURIDomains, err = getValues(excluded); err != nil {
-		return false, err
-	}
-	out.PermittedDNSDomainsCritical = e.Critical
-
-	return unhandled, nil
-}
-
-func processExtensions(out *Certificate) error {
-	var err error
-	for _, e := range out.Extensions {
-		unhandled := false
-
-		if len(e.Id) == 4 && e.Id[0] == 2 && e.Id[1] == 5 && e.Id[2] == 29 {
-			switch e.Id[3] {
-			case 15:
-				out.KeyUsage, err = parseKeyUsageExtension(e.Value)
-				if err != nil {
-					return err
-				}
-			case 19:
-				out.IsCA, out.MaxPathLen, err = parseBasicConstraintsExtension(e.Value)
-				if err != nil {
-					return err
-				}
-				out.BasicConstraintsValid = true
-				out.MaxPathLenZero = out.MaxPathLen == 0
-			case 17:
-				out.DNSNames, out.EmailAddresses, out.IPAddresses, out.URIs, err = parseSANExtension(e.Value)
-				if err != nil {
-					return err
-				}
-
-				if len(out.DNSNames) == 0 && len(out.EmailAddresses) == 0 && len(out.IPAddresses) == 0 && len(out.URIs) == 0 {
-					// If we didn't parse anything then we do the critical check, below.
-					unhandled = true
-				}
-
-			case 30:
-				unhandled, err = parseNameConstraintsExtension(out, e)
-				if err != nil {
-					return err
-				}
-
-			case 31:
-				// RFC 5280, 4.2.1.13
-
-				// CRLDistributionPoints ::= SEQUENCE SIZE (1..MAX) OF DistributionPoint
-				//
-				// DistributionPoint ::= SEQUENCE {
-				//     distributionPoint       [0]     DistributionPointName OPTIONAL,
-				//     reasons                 [1]     ReasonFlags OPTIONAL,
-				//     cRLIssuer               [2]     GeneralNames OPTIONAL }
-				//
-				// DistributionPointName ::= CHOICE {
-				//     fullName                [0]     GeneralNames,
-				//     nameRelativeToCRLIssuer [1]     RelativeDistinguishedName }
-				val := cryptobyte.String(e.Value)
-				if !val.ReadASN1(&val, cryptobyte_asn1.SEQUENCE) {
-					return errors.New("x509: invalid CRL distribution points")
-				}
-				for !val.Empty() {
-					var dpDER cryptobyte.String
-					if !val.ReadASN1(&dpDER, cryptobyte_asn1.SEQUENCE) {
-						return errors.New("x509: invalid CRL distribution point")
-					}
-					var dpNameDER cryptobyte.String
-					var dpNamePresent bool
-					if !dpDER.ReadOptionalASN1(&dpNameDER, &dpNamePresent, cryptobyte_asn1.Tag(0).Constructed().ContextSpecific()) {
-						return errors.New("x509: invalid CRL distribution point")
-					}
-					if !dpNamePresent {
-						continue
-					}
-					if !dpNameDER.ReadASN1(&dpNameDER, cryptobyte_asn1.Tag(0).Constructed().ContextSpecific()) {
-						return errors.New("x509: invalid CRL distribution point")
-					}
-					for !dpNameDER.Empty() {
-						if !dpNameDER.PeekASN1Tag(cryptobyte_asn1.Tag(6).ContextSpecific()) {
-							break
-						}
-						var uri cryptobyte.String
-						if !dpNameDER.ReadASN1(&uri, cryptobyte_asn1.Tag(6).ContextSpecific()) {
-							return errors.New("x509: invalid CRL distribution point")
-						}
-						out.CRLDistributionPoints = append(out.CRLDistributionPoints, string(uri))
-					}
-				}
-
-			case 35:
-				// RFC 5280, 4.2.1.1
-				val := cryptobyte.String(e.Value)
-				var akid cryptobyte.String
-				if !val.ReadASN1(&akid, cryptobyte_asn1.SEQUENCE) {
-					return errors.New("x509: invalid authority key identifier")
-				}
-				if akid.PeekASN1Tag(cryptobyte_asn1.Tag(0).ContextSpecific()) {
-					if !akid.ReadASN1(&akid, cryptobyte_asn1.Tag(0).ContextSpecific()) {
-						return errors.New("x509: invalid authority key identifier")
-					}
-					out.AuthorityKeyId = akid
-				}
-			case 37:
-				out.ExtKeyUsage, out.UnknownExtKeyUsage, err = parseExtKeyUsageExtension(e.Value)
-				if err != nil {
-					return err
-				}
-			case 14:
-				// RFC 5280, 4.2.1.2
-				val := cryptobyte.String(e.Value)
-				var skid cryptobyte.String
-				if !val.ReadASN1(&skid, cryptobyte_asn1.OCTET_STRING) {
-					return errors.New("x509: invalid subject key identifier")
-				}
-				out.SubjectKeyId = skid
-			case 32:
-				out.PolicyIdentifiers, err = parseCertificatePoliciesExtension(e.Value)
-				if err != nil {
-					return err
-				}
-			default:
-				// Unknown extensions are recorded if critical.
-				unhandled = true
-			}
-		} else if e.Id.Equal(oidExtensionAuthorityInfoAccess) {
-			// RFC 5280 4.2.2.1: Authority Information Access
-			val := cryptobyte.String(e.Value)
-			if !val.ReadASN1(&val, cryptobyte_asn1.SEQUENCE) {
-				return errors.New("x509: invalid authority info access")
-			}
-			for !val.Empty() {
-				var aiaDER cryptobyte.String
-				if !val.ReadASN1(&aiaDER, cryptobyte_asn1.SEQUENCE) {
-					return errors.New("x509: invalid authority info access")
-				}
-				var method asn1.ObjectIdentifier
-				if !aiaDER.ReadASN1ObjectIdentifier(&method) {
-					return errors.New("x509: invalid authority info access")
-				}
-				if !aiaDER.PeekASN1Tag(cryptobyte_asn1.Tag(6).ContextSpecific()) {
-					continue
-				}
-				if !aiaDER.ReadASN1(&aiaDER, cryptobyte_asn1.Tag(6).ContextSpecific()) {
-					return errors.New("x509: invalid authority info access")
-				}
-				switch {
-				case method.Equal(oidAuthorityInfoAccessOcsp):
-					out.OCSPServer = append(out.OCSPServer, string(aiaDER))
-				case method.Equal(oidAuthorityInfoAccessIssuers):
-					out.IssuingCertificateURL = append(out.IssuingCertificateURL, string(aiaDER))
-				}
-			}
-		} else {
-			// Unknown extensions are recorded if critical.
-			unhandled = true
-		}
-
-		if e.Critical && unhandled {
-			out.UnhandledCriticalExtensions = append(out.UnhandledCriticalExtensions, e.Id)
-		}
-	}
-
-	return nil
-}
-
-func parseCertificate(der []byte) (*Certificate, error) {
-	cert := &Certificate{}
-
-	input := cryptobyte.String(der)
-	// we read the SEQUENCE including length and tag bytes so that
-	// we can populate Certificate.Raw, before unwrapping the
-	// SEQUENCE so it can be operated on
-	if !input.ReadASN1Element(&input, cryptobyte_asn1.SEQUENCE) {
-		return nil, errors.New("x509: malformed certificate")
-	}
-	cert.Raw = input
-	if !input.ReadASN1(&input, cryptobyte_asn1.SEQUENCE) {
-		return nil, errors.New("x509: malformed certificate")
-	}
-
-	var tbs cryptobyte.String
-	// do the same trick again as above to extract the raw
-	// bytes for Certificate.RawTBSCertificate
-	if !input.ReadASN1Element(&tbs, cryptobyte_asn1.SEQUENCE) {
-		return nil, errors.New("x509: malformed tbs certificate")
-	}
-	cert.RawTBSCertificate = tbs
-	if !tbs.ReadASN1(&tbs, cryptobyte_asn1.SEQUENCE) {
-		return nil, errors.New("x509: malformed tbs certificate")
-	}
-
-	if !tbs.ReadOptionalASN1Integer(&cert.Version, cryptobyte_asn1.Tag(0).Constructed().ContextSpecific(), 0) {
-		return nil, errors.New("x509: malformed version")
-	}
-	if cert.Version < 0 {
-		return nil, errors.New("x509: malformed version")
-	}
-	// for backwards compat reasons Version is one-indexed,
-	// rather than zero-indexed as defined in 5280
-	cert.Version++
-	if cert.Version > 3 {
-		return nil, errors.New("x509: invalid version")
-	}
-
-	serial := new(big.Int)
-	if !tbs.ReadASN1Integer(serial) {
-		return nil, errors.New("x509: malformed serial number")
-	}
-	// we ignore the presence of negative serial numbers because
-	// of their prevalence, despite them being invalid
-	// TODO(rolandshoemaker): revist this decision, there are currently
-	// only 10 trusted certificates with negative serial numbers
-	// according to censys.io.
-	cert.SerialNumber = serial
-
-	var sigAISeq cryptobyte.String
-	if !tbs.ReadASN1(&sigAISeq, cryptobyte_asn1.SEQUENCE) {
-		return nil, errors.New("x509: malformed signature algorithm identifier")
-	}
-	// Before parsing the inner algorithm identifier, extract
-	// the outer algorithm identifier and make sure that they
-	// match.
-	var outerSigAISeq cryptobyte.String
-	if !input.ReadASN1(&outerSigAISeq, cryptobyte_asn1.SEQUENCE) {
-		return nil, errors.New("x509: malformed algorithm identifier")
-	}
-	if !bytes.Equal(outerSigAISeq, sigAISeq) {
-		return nil, errors.New("x509: inner and outer signature algorithm identifiers don't match")
-	}
-	sigAI, err := parseAI(sigAISeq)
-	if err != nil {
-		return nil, err
-	}
-	cert.SignatureAlgorithm = getSignatureAlgorithmFromAI(sigAI)
-
-	var issuerSeq cryptobyte.String
-	if !tbs.ReadASN1Element(&issuerSeq, cryptobyte_asn1.SEQUENCE) {
-		return nil, errors.New("x509: malformed issuer")
-	}
-	cert.RawIssuer = issuerSeq
-	issuerRDNs, err := parseName(issuerSeq)
-	if err != nil {
-		return nil, err
-	}
-	cert.Issuer.FillFromRDNSequence(issuerRDNs)
-
-	var validity cryptobyte.String
-	if !tbs.ReadASN1(&validity, cryptobyte_asn1.SEQUENCE) {
-		return nil, errors.New("x509: malformed validity")
-	}
-	cert.NotBefore, cert.NotAfter, err = parseValidity(validity)
-	if err != nil {
-		return nil, err
-	}
-
-	var subjectSeq cryptobyte.String
-	if !tbs.ReadASN1Element(&subjectSeq, cryptobyte_asn1.SEQUENCE) {
-		return nil, errors.New("x509: malformed issuer")
-	}
-	cert.RawSubject = subjectSeq
-	subjectRDNs, err := parseName(subjectSeq)
-	if err != nil {
-		return nil, err
-	}
-	cert.Subject.FillFromRDNSequence(subjectRDNs)
-
-	var spki cryptobyte.String
-	if !tbs.ReadASN1Element(&spki, cryptobyte_asn1.SEQUENCE) {
-		return nil, errors.New("x509: malformed spki")
-	}
-	cert.RawSubjectPublicKeyInfo = spki
-	if !spki.ReadASN1(&spki, cryptobyte_asn1.SEQUENCE) {
-		return nil, errors.New("x509: malformed spki")
-	}
-	var pkAISeq cryptobyte.String
-	if !spki.ReadASN1(&pkAISeq, cryptobyte_asn1.SEQUENCE) {
-		return nil, errors.New("x509: malformed public key algorithm identifier")
-	}
-	pkAI, err := parseAI(pkAISeq)
-	if err != nil {
-		return nil, err
-	}
-	cert.PublicKeyAlgorithm = getPublicKeyAlgorithmFromOID(pkAI.Algorithm)
-	var spk asn1.BitString
-	if !spki.ReadASN1BitString(&spk) {
-		return nil, errors.New("x509: malformed subjectPublicKey")
-	}
-	cert.PublicKey, err = parsePublicKey(cert.PublicKeyAlgorithm, &publicKeyInfo{
-		Algorithm: pkAI,
-		PublicKey: spk,
-	})
-	if err != nil {
-		return nil, err
-	}
-
-	if cert.Version > 1 {
-		if !tbs.SkipOptionalASN1(cryptobyte_asn1.Tag(1).ContextSpecific()) {
-			return nil, errors.New("x509: malformed issuerUniqueID")
-		}
-		if !tbs.SkipOptionalASN1(cryptobyte_asn1.Tag(2).ContextSpecific()) {
-			return nil, errors.New("x509: malformed subjectUniqueID")
-		}
-		if cert.Version == 3 {
-			var extensions cryptobyte.String
-			var present bool
-			if !tbs.ReadOptionalASN1(&extensions, &present, cryptobyte_asn1.Tag(3).Constructed().ContextSpecific()) {
-				return nil, errors.New("x509: malformed extensions")
-			}
-			if present {
-				if !extensions.ReadASN1(&extensions, cryptobyte_asn1.SEQUENCE) {
-					return nil, errors.New("x509: malformed extensions")
-				}
-				for !extensions.Empty() {
-					var extension cryptobyte.String
-					if !extensions.ReadASN1(&extension, cryptobyte_asn1.SEQUENCE) {
-						return nil, errors.New("x509: malformed extension")
-					}
-					ext, err := parseExtension(extension)
-					if err != nil {
-						return nil, err
-					}
-					cert.Extensions = append(cert.Extensions, ext)
-				}
-				err = processExtensions(cert)
-				if err != nil {
-					return nil, err
-				}
-			}
-		}
-	}
-
-	var signature asn1.BitString
-	if !input.ReadASN1BitString(&signature) {
-		return nil, errors.New("x509: malformed signature")
-	}
-	cert.Signature = signature.RightAlign()
-
-	return cert, nil
-}
-
-// ParseCertificate parses a single certificate from the given ASN.1 DER data.
-func ParseCertificate(der []byte) (*Certificate, error) {
-	cert, err := parseCertificate(der)
-	if err != nil {
-		return nil, err
-	}
-	if len(der) != len(cert.Raw) {
-		return nil, errors.New("x509: trailing data")
-	}
-	return cert, err
-}
-
-// ParseCertificates parses one or more certificates from the given ASN.1 DER
-// data. The certificates must be concatenated with no intermediate padding.
-func ParseCertificates(der []byte) ([]*Certificate, error) {
-	var certs []*Certificate
-	for len(der) > 0 {
-		cert, err := parseCertificate(der)
-		if err != nil {
-			return nil, err
-		}
-		certs = append(certs, cert)
-		der = der[len(cert.Raw):]
-	}
-	return certs, nil
-}
diff --git a/contrib/go/_std_1.18/src/crypto/x509/pkix/pkix.go b/contrib/go/_std_1.18/src/crypto/x509/pkix/pkix.go
deleted file mode 100644
index e9179ed067..0000000000
--- a/contrib/go/_std_1.18/src/crypto/x509/pkix/pkix.go
+++ /dev/null
@@ -1,316 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package pkix contains shared, low level structures used for ASN.1 parsing
-// and serialization of X.509 certificates, CRL and OCSP.
-package pkix
-
-import (
-	"encoding/asn1"
-	"encoding/hex"
-	"fmt"
-	"math/big"
-	"time"
-)
-
-// AlgorithmIdentifier represents the ASN.1 structure of the same name. See RFC
-// 5280, section 4.1.1.2.
-type AlgorithmIdentifier struct {
-	Algorithm  asn1.ObjectIdentifier
-	Parameters asn1.RawValue `asn1:"optional"`
-}
-
-type RDNSequence []RelativeDistinguishedNameSET
-
-var attributeTypeNames = map[string]string{
-	"2.5.4.6":  "C",
-	"2.5.4.10": "O",
-	"2.5.4.11": "OU",
-	"2.5.4.3":  "CN",
-	"2.5.4.5":  "SERIALNUMBER",
-	"2.5.4.7":  "L",
-	"2.5.4.8":  "ST",
-	"2.5.4.9":  "STREET",
-	"2.5.4.17": "POSTALCODE",
-}
-
-// String returns a string representation of the sequence r,
-// roughly following the RFC 2253 Distinguished Names syntax.
-func (r RDNSequence) String() string {
-	s := ""
-	for i := 0; i < len(r); i++ {
-		rdn := r[len(r)-1-i]
-		if i > 0 {
-			s += ","
-		}
-		for j, tv := range rdn {
-			if j > 0 {
-				s += "+"
-			}
-
-			oidString := tv.Type.String()
-			typeName, ok := attributeTypeNames[oidString]
-			if !ok {
-				derBytes, err := asn1.Marshal(tv.Value)
-				if err == nil {
-					s += oidString + "=#" + hex.EncodeToString(derBytes)
-					continue // No value escaping necessary.
-				}
-
-				typeName = oidString
-			}
-
-			valueString := fmt.Sprint(tv.Value)
-			escaped := make([]rune, 0, len(valueString))
-
-			for k, c := range valueString {
-				escape := false
-
-				switch c {
-				case ',', '+', '"', '\\', '<', '>', ';':
-					escape = true
-
-				case ' ':
-					escape = k == 0 || k == len(valueString)-1
-
-				case '#':
-					escape = k == 0
-				}
-
-				if escape {
-					escaped = append(escaped, '\\', c)
-				} else {
-					escaped = append(escaped, c)
-				}
-			}
-
-			s += typeName + "=" + string(escaped)
-		}
-	}
-
-	return s
-}
-
-type RelativeDistinguishedNameSET []AttributeTypeAndValue
-
-// AttributeTypeAndValue mirrors the ASN.1 structure of the same name in
-// RFC 5280, Section 4.1.2.4.
-type AttributeTypeAndValue struct {
-	Type  asn1.ObjectIdentifier
-	Value any
-}
-
-// AttributeTypeAndValueSET represents a set of ASN.1 sequences of
-// AttributeTypeAndValue sequences from RFC 2986 (PKCS #10).
-type AttributeTypeAndValueSET struct {
-	Type  asn1.ObjectIdentifier
-	Value [][]AttributeTypeAndValue `asn1:"set"`
-}
-
-// Extension represents the ASN.1 structure of the same name. See RFC
-// 5280, section 4.2.
-type Extension struct {
-	Id       asn1.ObjectIdentifier
-	Critical bool `asn1:"optional"`
-	Value    []byte
-}
-
-// Name represents an X.509 distinguished name. This only includes the common
-// elements of a DN. Note that Name is only an approximation of the X.509
-// structure. If an accurate representation is needed, asn1.Unmarshal the raw
-// subject or issuer as an RDNSequence.
-type Name struct {
-	Country, Organization, OrganizationalUnit []string
-	Locality, Province                        []string
-	StreetAddress, PostalCode                 []string
-	SerialNumber, CommonName                  string
-
-	// Names contains all parsed attributes. When parsing distinguished names,
-	// this can be used to extract non-standard attributes that are not parsed
-	// by this package. When marshaling to RDNSequences, the Names field is
-	// ignored, see ExtraNames.
-	Names []AttributeTypeAndValue
-
-	// ExtraNames contains attributes to be copied, raw, into any marshaled
-	// distinguished names. Values override any attributes with the same OID.
-	// The ExtraNames field is not populated when parsing, see Names.
-	ExtraNames []AttributeTypeAndValue
-}
-
-// FillFromRDNSequence populates n from the provided RDNSequence.
-// Multi-entry RDNs are flattened, all entries are added to the
-// relevant n fields, and the grouping is not preserved.
-func (n *Name) FillFromRDNSequence(rdns *RDNSequence) {
-	for _, rdn := range *rdns {
-		if len(rdn) == 0 {
-			continue
-		}
-
-		for _, atv := range rdn {
-			n.Names = append(n.Names, atv)
-			value, ok := atv.Value.(string)
-			if !ok {
-				continue
-			}
-
-			t := atv.Type
-			if len(t) == 4 && t[0] == 2 && t[1] == 5 && t[2] == 4 {
-				switch t[3] {
-				case 3:
-					n.CommonName = value
-				case 5:
-					n.SerialNumber = value
-				case 6:
-					n.Country = append(n.Country, value)
-				case 7:
-					n.Locality = append(n.Locality, value)
-				case 8:
-					n.Province = append(n.Province, value)
-				case 9:
-					n.StreetAddress = append(n.StreetAddress, value)
-				case 10:
-					n.Organization = append(n.Organization, value)
-				case 11:
-					n.OrganizationalUnit = append(n.OrganizationalUnit, value)
-				case 17:
-					n.PostalCode = append(n.PostalCode, value)
-				}
-			}
-		}
-	}
-}
-
-var (
-	oidCountry            = []int{2, 5, 4, 6}
-	oidOrganization       = []int{2, 5, 4, 10}
-	oidOrganizationalUnit = []int{2, 5, 4, 11}
-	oidCommonName         = []int{2, 5, 4, 3}
-	oidSerialNumber       = []int{2, 5, 4, 5}
-	oidLocality           = []int{2, 5, 4, 7}
-	oidProvince           = []int{2, 5, 4, 8}
-	oidStreetAddress      = []int{2, 5, 4, 9}
-	oidPostalCode         = []int{2, 5, 4, 17}
-)
-
-// appendRDNs appends a relativeDistinguishedNameSET to the given RDNSequence
-// and returns the new value. The relativeDistinguishedNameSET contains an
-// attributeTypeAndValue for each of the given values. See RFC 5280, A.1, and
-// search for AttributeTypeAndValue.
-func (n Name) appendRDNs(in RDNSequence, values []string, oid asn1.ObjectIdentifier) RDNSequence {
-	if len(values) == 0 || oidInAttributeTypeAndValue(oid, n.ExtraNames) {
-		return in
-	}
-
-	s := make([]AttributeTypeAndValue, len(values))
-	for i, value := range values {
-		s[i].Type = oid
-		s[i].Value = value
-	}
-
-	return append(in, s)
-}
-
-// ToRDNSequence converts n into a single RDNSequence. The following
-// attributes are encoded as multi-value RDNs:
-//
-//  - Country
-//  - Organization
-//  - OrganizationalUnit
-//  - Locality
-//  - Province
-//  - StreetAddress
-//  - PostalCode
-//
-// Each ExtraNames entry is encoded as an individual RDN.
-func (n Name) ToRDNSequence() (ret RDNSequence) {
-	ret = n.appendRDNs(ret, n.Country, oidCountry)
-	ret = n.appendRDNs(ret, n.Province, oidProvince)
-	ret = n.appendRDNs(ret, n.Locality, oidLocality)
-	ret = n.appendRDNs(ret, n.StreetAddress, oidStreetAddress)
-	ret = n.appendRDNs(ret, n.PostalCode, oidPostalCode)
-	ret = n.appendRDNs(ret, n.Organization, oidOrganization)
-	ret = n.appendRDNs(ret, n.OrganizationalUnit, oidOrganizationalUnit)
-	if len(n.CommonName) > 0 {
-		ret = n.appendRDNs(ret, []string{n.CommonName}, oidCommonName)
-	}
-	if len(n.SerialNumber) > 0 {
-		ret = n.appendRDNs(ret, []string{n.SerialNumber}, oidSerialNumber)
-	}
-	for _, atv := range n.ExtraNames {
-		ret = append(ret, []AttributeTypeAndValue{atv})
-	}
-
-	return ret
-}
-
-// String returns the string form of n, roughly following
-// the RFC 2253 Distinguished Names syntax.
-func (n Name) String() string {
-	var rdns RDNSequence
-	// If there are no ExtraNames, surface the parsed value (all entries in
-	// Names) instead.
-	if n.ExtraNames == nil {
-		for _, atv := range n.Names {
-			t := atv.Type
-			if len(t) == 4 && t[0] == 2 && t[1] == 5 && t[2] == 4 {
-				switch t[3] {
-				case 3, 5, 6, 7, 8, 9, 10, 11, 17:
-					// These attributes were already parsed into named fields.
-					continue
-				}
-			}
-			// Place non-standard parsed values at the beginning of the sequence
-			// so they will be at the end of the string. See Issue 39924.
-			rdns = append(rdns, []AttributeTypeAndValue{atv})
-		}
-	}
-	rdns = append(rdns, n.ToRDNSequence()...)
-	return rdns.String()
-}
-
-// oidInAttributeTypeAndValue reports whether a type with the given OID exists
-// in atv.
-func oidInAttributeTypeAndValue(oid asn1.ObjectIdentifier, atv []AttributeTypeAndValue) bool {
-	for _, a := range atv {
-		if a.Type.Equal(oid) {
-			return true
-		}
-	}
-	return false
-}
-
-// CertificateList represents the ASN.1 structure of the same name. See RFC
-// 5280, section 5.1. Use Certificate.CheckCRLSignature to verify the
-// signature.
-type CertificateList struct {
-	TBSCertList        TBSCertificateList
-	SignatureAlgorithm AlgorithmIdentifier
-	SignatureValue     asn1.BitString
-}
-
-// HasExpired reports whether certList should have been updated by now.
-func (certList *CertificateList) HasExpired(now time.Time) bool {
-	return !now.Before(certList.TBSCertList.NextUpdate)
-}
-
-// TBSCertificateList represents the ASN.1 structure of the same name. See RFC
-// 5280, section 5.1.
-type TBSCertificateList struct {
-	Raw                 asn1.RawContent
-	Version             int `asn1:"optional,default:0"`
-	Signature           AlgorithmIdentifier
-	Issuer              RDNSequence
-	ThisUpdate          time.Time
-	NextUpdate          time.Time            `asn1:"optional"`
-	RevokedCertificates []RevokedCertificate `asn1:"optional"`
-	Extensions          []Extension          `asn1:"tag:0,optional,explicit"`
-}
-
-// RevokedCertificate represents the ASN.1 structure of the same name. See RFC
-// 5280, section 5.1.
-type RevokedCertificate struct {
-	SerialNumber   *big.Int
-	RevocationTime time.Time
-	Extensions     []Extension `asn1:"optional"`
-}
diff --git a/contrib/go/_std_1.18/src/crypto/x509/root.go b/contrib/go/_std_1.18/src/crypto/x509/root.go
deleted file mode 100644
index eef9c047b2..0000000000
--- a/contrib/go/_std_1.18/src/crypto/x509/root.go
+++ /dev/null
@@ -1,31 +0,0 @@
-// Copyright 2012 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package x509
-
-// To update the embedded iOS root store, update the -version
-// argument to the latest security_certificates version from
-// https://opensource.apple.com/source/security_certificates/
-// and run "go generate". See https://golang.org/issue/38843.
-//go:generate go run root_ios_gen.go -version 55188.120.1.0.1
-
-import "sync"
-
-var (
-	once           sync.Once
-	systemRoots    *CertPool
-	systemRootsErr error
-)
-
-func systemRootsPool() *CertPool {
-	once.Do(initSystemRoots)
-	return systemRoots
-}
-
-func initSystemRoots() {
-	systemRoots, systemRootsErr = loadSystemRoots()
-	if systemRootsErr != nil {
-		systemRoots = nil
-	}
-}
diff --git a/contrib/go/_std_1.18/src/crypto/x509/root_darwin.go b/contrib/go/_std_1.18/src/crypto/x509/root_darwin.go
deleted file mode 100644
index ad365f577e..0000000000
--- a/contrib/go/_std_1.18/src/crypto/x509/root_darwin.go
+++ /dev/null
@@ -1,113 +0,0 @@
-// Copyright 2020 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package x509
-
-import (
-	macOS "crypto/x509/internal/macos"
-	"errors"
-)
-
-func (c *Certificate) systemVerify(opts *VerifyOptions) (chains [][]*Certificate, err error) {
-	certs := macOS.CFArrayCreateMutable()
-	defer macOS.ReleaseCFArray(certs)
-	leaf := macOS.SecCertificateCreateWithData(c.Raw)
-	if leaf == 0 {
-		return nil, errors.New("invalid leaf certificate")
-	}
-	macOS.CFArrayAppendValue(certs, leaf)
-	if opts.Intermediates != nil {
-		for _, lc := range opts.Intermediates.lazyCerts {
-			c, err := lc.getCert()
-			if err != nil {
-				return nil, err
-			}
-			sc := macOS.SecCertificateCreateWithData(c.Raw)
-			if sc != 0 {
-				macOS.CFArrayAppendValue(certs, sc)
-			}
-		}
-	}
-
-	policies := macOS.CFArrayCreateMutable()
-	defer macOS.ReleaseCFArray(policies)
-	sslPolicy := macOS.SecPolicyCreateSSL(opts.DNSName)
-	macOS.CFArrayAppendValue(policies, sslPolicy)
-
-	trustObj, err := macOS.SecTrustCreateWithCertificates(certs, policies)
-	if err != nil {
-		return nil, err
-	}
-	defer macOS.CFRelease(trustObj)
-
-	if !opts.CurrentTime.IsZero() {
-		dateRef := macOS.TimeToCFDateRef(opts.CurrentTime)
-		defer macOS.CFRelease(dateRef)
-		if err := macOS.SecTrustSetVerifyDate(trustObj, dateRef); err != nil {
-			return nil, err
-		}
-	}
-
-	// TODO(roland): we may want to allow passing in SCTs via VerifyOptions and
-	// set them via SecTrustSetSignedCertificateTimestamps, since Apple will
-	// always enforce its SCT requirements, and there are still _some_ people
-	// using TLS or OCSP for that.
-
-	if err := macOS.SecTrustEvaluateWithError(trustObj); err != nil {
-		return nil, err
-	}
-
-	chain := [][]*Certificate{{}}
-	numCerts := macOS.SecTrustGetCertificateCount(trustObj)
-	for i := 0; i < numCerts; i++ {
-		certRef := macOS.SecTrustGetCertificateAtIndex(trustObj, i)
-		cert, err := exportCertificate(certRef)
-		if err != nil {
-			return nil, err
-		}
-		chain[0] = append(chain[0], cert)
-	}
-	if len(chain[0]) == 0 {
-		// This should _never_ happen, but to be safe
-		return nil, errors.New("x509: macOS certificate verification internal error")
-	}
-
-	if opts.DNSName != "" {
-		// If we have a DNS name, apply our own name verification
-		if err := chain[0][0].VerifyHostname(opts.DNSName); err != nil {
-			return nil, err
-		}
-	}
-
-	keyUsages := opts.KeyUsages
-	if len(keyUsages) == 0 {
-		keyUsages = []ExtKeyUsage{ExtKeyUsageServerAuth}
-	}
-
-	// If any key usage is acceptable then we're done.
-	for _, usage := range keyUsages {
-		if usage == ExtKeyUsageAny {
-			return chain, nil
-		}
-	}
-
-	if !checkChainForKeyUsage(chain[0], keyUsages) {
-		return nil, CertificateInvalidError{c, IncompatibleUsage, ""}
-	}
-
-	return chain, nil
-}
-
-// exportCertificate returns a *Certificate for a SecCertificateRef.
-func exportCertificate(cert macOS.CFRef) (*Certificate, error) {
-	data, err := macOS.SecCertificateCopyData(cert)
-	if err != nil {
-		return nil, err
-	}
-	return ParseCertificate(data)
-}
-
-func loadSystemRoots() (*CertPool, error) {
-	return &CertPool{systemPool: true}, nil
-}
diff --git a/contrib/go/_std_1.18/src/crypto/x509/sec1.go b/contrib/go/_std_1.18/src/crypto/x509/sec1.go
deleted file mode 100644
index 52c108ff1d..0000000000
--- a/contrib/go/_std_1.18/src/crypto/x509/sec1.go
+++ /dev/null
@@ -1,120 +0,0 @@
-// Copyright 2012 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package x509
-
-import (
-	"crypto/ecdsa"
-	"crypto/elliptic"
-	"encoding/asn1"
-	"errors"
-	"fmt"
-	"math/big"
-)
-
-const ecPrivKeyVersion = 1
-
-// ecPrivateKey reflects an ASN.1 Elliptic Curve Private Key Structure.
-// References:
-//   RFC 5915
-//   SEC1 - http://www.secg.org/sec1-v2.pdf
-// Per RFC 5915 the NamedCurveOID is marked as ASN.1 OPTIONAL, however in
-// most cases it is not.
-type ecPrivateKey struct {
-	Version       int
-	PrivateKey    []byte
-	NamedCurveOID asn1.ObjectIdentifier `asn1:"optional,explicit,tag:0"`
-	PublicKey     asn1.BitString        `asn1:"optional,explicit,tag:1"`
-}
-
-// ParseECPrivateKey parses an EC private key in SEC 1, ASN.1 DER form.
-//
-// This kind of key is commonly encoded in PEM blocks of type "EC PRIVATE KEY".
-func ParseECPrivateKey(der []byte) (*ecdsa.PrivateKey, error) {
-	return parseECPrivateKey(nil, der)
-}
-
-// MarshalECPrivateKey converts an EC private key to SEC 1, ASN.1 DER form.
-//
-// This kind of key is commonly encoded in PEM blocks of type "EC PRIVATE KEY".
-// For a more flexible key format which is not EC specific, use
-// MarshalPKCS8PrivateKey.
-func MarshalECPrivateKey(key *ecdsa.PrivateKey) ([]byte, error) {
-	oid, ok := oidFromNamedCurve(key.Curve)
-	if !ok {
-		return nil, errors.New("x509: unknown elliptic curve")
-	}
-
-	return marshalECPrivateKeyWithOID(key, oid)
-}
-
-// marshalECPrivateKey marshals an EC private key into ASN.1, DER format and
-// sets the curve ID to the given OID, or omits it if OID is nil.
-func marshalECPrivateKeyWithOID(key *ecdsa.PrivateKey, oid asn1.ObjectIdentifier) ([]byte, error) {
-	privateKey := make([]byte, (key.Curve.Params().N.BitLen()+7)/8)
-	return asn1.Marshal(ecPrivateKey{
-		Version:       1,
-		PrivateKey:    key.D.FillBytes(privateKey),
-		NamedCurveOID: oid,
-		PublicKey:     asn1.BitString{Bytes: elliptic.Marshal(key.Curve, key.X, key.Y)},
-	})
-}
-
-// parseECPrivateKey parses an ASN.1 Elliptic Curve Private Key Structure.
-// The OID for the named curve may be provided from another source (such as
-// the PKCS8 container) - if it is provided then use this instead of the OID
-// that may exist in the EC private key structure.
-func parseECPrivateKey(namedCurveOID *asn1.ObjectIdentifier, der []byte) (key *ecdsa.PrivateKey, err error) {
-	var privKey ecPrivateKey
-	if _, err := asn1.Unmarshal(der, &privKey); err != nil {
-		if _, err := asn1.Unmarshal(der, &pkcs8{}); err == nil {
-			return nil, errors.New("x509: failed to parse private key (use ParsePKCS8PrivateKey instead for this key format)")
-		}
-		if _, err := asn1.Unmarshal(der, &pkcs1PrivateKey{}); err == nil {
-			return nil, errors.New("x509: failed to parse private key (use ParsePKCS1PrivateKey instead for this key format)")
-		}
-		return nil, errors.New("x509: failed to parse EC private key: " + err.Error())
-	}
-	if privKey.Version != ecPrivKeyVersion {
-		return nil, fmt.Errorf("x509: unknown EC private key version %d", privKey.Version)
-	}
-
-	var curve elliptic.Curve
-	if namedCurveOID != nil {
-		curve = namedCurveFromOID(*namedCurveOID)
-	} else {
-		curve = namedCurveFromOID(privKey.NamedCurveOID)
-	}
-	if curve == nil {
-		return nil, errors.New("x509: unknown elliptic curve")
-	}
-
-	k := new(big.Int).SetBytes(privKey.PrivateKey)
-	curveOrder := curve.Params().N
-	if k.Cmp(curveOrder) >= 0 {
-		return nil, errors.New("x509: invalid elliptic curve private key value")
-	}
-	priv := new(ecdsa.PrivateKey)
-	priv.Curve = curve
-	priv.D = k
-
-	privateKey := make([]byte, (curveOrder.BitLen()+7)/8)
-
-	// Some private keys have leading zero padding. This is invalid
-	// according to [SEC1], but this code will ignore it.
-	for len(privKey.PrivateKey) > len(privateKey) {
-		if privKey.PrivateKey[0] != 0 {
-			return nil, errors.New("x509: invalid private key length")
-		}
-		privKey.PrivateKey = privKey.PrivateKey[1:]
-	}
-
-	// Some private keys remove all leading zeros, this is also invalid
-	// according to [SEC1] but since OpenSSL used to do this, we ignore
-	// this too.
-	copy(privateKey[len(privateKey)-len(privKey.PrivateKey):], privKey.PrivateKey)
-	priv.X, priv.Y = curve.ScalarBaseMult(privateKey)
-
-	return priv, nil
-}
diff --git a/contrib/go/_std_1.18/src/crypto/x509/verify.go b/contrib/go/_std_1.18/src/crypto/x509/verify.go
deleted file mode 100644
index 4be4eb6095..0000000000
--- a/contrib/go/_std_1.18/src/crypto/x509/verify.go
+++ /dev/null
@@ -1,1114 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package x509
-
-import (
-	"bytes"
-	"errors"
-	"fmt"
-	"net"
-	"net/url"
-	"reflect"
-	"runtime"
-	"strings"
-	"time"
-	"unicode/utf8"
-)
-
-type InvalidReason int
-
-const (
-	// NotAuthorizedToSign results when a certificate is signed by another
-	// which isn't marked as a CA certificate.
-	NotAuthorizedToSign InvalidReason = iota
-	// Expired results when a certificate has expired, based on the time
-	// given in the VerifyOptions.
-	Expired
-	// CANotAuthorizedForThisName results when an intermediate or root
-	// certificate has a name constraint which doesn't permit a DNS or
-	// other name (including IP address) in the leaf certificate.
-	CANotAuthorizedForThisName
-	// TooManyIntermediates results when a path length constraint is
-	// violated.
-	TooManyIntermediates
-	// IncompatibleUsage results when the certificate's key usage indicates
-	// that it may only be used for a different purpose.
-	IncompatibleUsage
-	// NameMismatch results when the subject name of a parent certificate
-	// does not match the issuer name in the child.
-	NameMismatch
-	// NameConstraintsWithoutSANs is a legacy error and is no longer returned.
-	NameConstraintsWithoutSANs
-	// UnconstrainedName results when a CA certificate contains permitted
-	// name constraints, but leaf certificate contains a name of an
-	// unsupported or unconstrained type.
-	UnconstrainedName
-	// TooManyConstraints results when the number of comparison operations
-	// needed to check a certificate exceeds the limit set by
-	// VerifyOptions.MaxConstraintComparisions. This limit exists to
-	// prevent pathological certificates can consuming excessive amounts of
-	// CPU time to verify.
-	TooManyConstraints
-	// CANotAuthorizedForExtKeyUsage results when an intermediate or root
-	// certificate does not permit a requested extended key usage.
-	CANotAuthorizedForExtKeyUsage
-)
-
-// CertificateInvalidError results when an odd error occurs. Users of this
-// library probably want to handle all these errors uniformly.
-type CertificateInvalidError struct {
-	Cert   *Certificate
-	Reason InvalidReason
-	Detail string
-}
-
-func (e CertificateInvalidError) Error() string {
-	switch e.Reason {
-	case NotAuthorizedToSign:
-		return "x509: certificate is not authorized to sign other certificates"
-	case Expired:
-		return "x509: certificate has expired or is not yet valid: " + e.Detail
-	case CANotAuthorizedForThisName:
-		return "x509: a root or intermediate certificate is not authorized to sign for this name: " + e.Detail
-	case CANotAuthorizedForExtKeyUsage:
-		return "x509: a root or intermediate certificate is not authorized for an extended key usage: " + e.Detail
-	case TooManyIntermediates:
-		return "x509: too many intermediates for path length constraint"
-	case IncompatibleUsage:
-		return "x509: certificate specifies an incompatible key usage"
-	case NameMismatch:
-		return "x509: issuer name does not match subject from issuing certificate"
-	case NameConstraintsWithoutSANs:
-		return "x509: issuer has name constraints but leaf doesn't have a SAN extension"
-	case UnconstrainedName:
-		return "x509: issuer has name constraints but leaf contains unknown or unconstrained name: " + e.Detail
-	}
-	return "x509: unknown error"
-}
-
-// HostnameError results when the set of authorized names doesn't match the
-// requested name.
-type HostnameError struct {
-	Certificate *Certificate
-	Host        string
-}
-
-func (h HostnameError) Error() string {
-	c := h.Certificate
-
-	if !c.hasSANExtension() && matchHostnames(c.Subject.CommonName, h.Host) {
-		return "x509: certificate relies on legacy Common Name field, use SANs instead"
-	}
-
-	var valid string
-	if ip := net.ParseIP(h.Host); ip != nil {
-		// Trying to validate an IP
-		if len(c.IPAddresses) == 0 {
-			return "x509: cannot validate certificate for " + h.Host + " because it doesn't contain any IP SANs"
-		}
-		for _, san := range c.IPAddresses {
-			if len(valid) > 0 {
-				valid += ", "
-			}
-			valid += san.String()
-		}
-	} else {
-		valid = strings.Join(c.DNSNames, ", ")
-	}
-
-	if len(valid) == 0 {
-		return "x509: certificate is not valid for any names, but wanted to match " + h.Host
-	}
-	return "x509: certificate is valid for " + valid + ", not " + h.Host
-}
-
-// UnknownAuthorityError results when the certificate issuer is unknown
-type UnknownAuthorityError struct {
-	Cert *Certificate
-	// hintErr contains an error that may be helpful in determining why an
-	// authority wasn't found.
-	hintErr error
-	// hintCert contains a possible authority certificate that was rejected
-	// because of the error in hintErr.
-	hintCert *Certificate
-}
-
-func (e UnknownAuthorityError) Error() string {
-	s := "x509: certificate signed by unknown authority"
-	if e.hintErr != nil {
-		certName := e.hintCert.Subject.CommonName
-		if len(certName) == 0 {
-			if len(e.hintCert.Subject.Organization) > 0 {
-				certName = e.hintCert.Subject.Organization[0]
-			} else {
-				certName = "serial:" + e.hintCert.SerialNumber.String()
-			}
-		}
-		s += fmt.Sprintf(" (possibly because of %q while trying to verify candidate authority certificate %q)", e.hintErr, certName)
-	}
-	return s
-}
-
-// SystemRootsError results when we fail to load the system root certificates.
-type SystemRootsError struct {
-	Err error
-}
-
-func (se SystemRootsError) Error() string {
-	msg := "x509: failed to load system roots and no roots provided"
-	if se.Err != nil {
-		return msg + "; " + se.Err.Error()
-	}
-	return msg
-}
-
-func (se SystemRootsError) Unwrap() error { return se.Err }
-
-// errNotParsed is returned when a certificate without ASN.1 contents is
-// verified. Platform-specific verification needs the ASN.1 contents.
-var errNotParsed = errors.New("x509: missing ASN.1 contents; use ParseCertificate")
-
-// VerifyOptions contains parameters for Certificate.Verify.
-type VerifyOptions struct {
-	// DNSName, if set, is checked against the leaf certificate with
-	// Certificate.VerifyHostname or the platform verifier.
-	DNSName string
-
-	// Intermediates is an optional pool of certificates that are not trust
-	// anchors, but can be used to form a chain from the leaf certificate to a
-	// root certificate.
-	Intermediates *CertPool
-	// Roots is the set of trusted root certificates the leaf certificate needs
-	// to chain up to. If nil, the system roots or the platform verifier are used.
-	Roots *CertPool
-
-	// CurrentTime is used to check the validity of all certificates in the
-	// chain. If zero, the current time is used.
-	CurrentTime time.Time
-
-	// KeyUsages specifies which Extended Key Usage values are acceptable. A
-	// chain is accepted if it allows any of the listed values. An empty list
-	// means ExtKeyUsageServerAuth. To accept any key usage, include ExtKeyUsageAny.
-	KeyUsages []ExtKeyUsage
-
-	// MaxConstraintComparisions is the maximum number of comparisons to
-	// perform when checking a given certificate's name constraints. If
-	// zero, a sensible default is used. This limit prevents pathological
-	// certificates from consuming excessive amounts of CPU time when
-	// validating. It does not apply to the platform verifier.
-	MaxConstraintComparisions int
-}
-
-const (
-	leafCertificate = iota
-	intermediateCertificate
-	rootCertificate
-)
-
-// rfc2821Mailbox represents a “mailbox” (which is an email address to most
-// people) by breaking it into the “local” (i.e. before the '@') and “domain”
-// parts.
-type rfc2821Mailbox struct {
-	local, domain string
-}
-
-// parseRFC2821Mailbox parses an email address into local and domain parts,
-// based on the ABNF for a “Mailbox” from RFC 2821. According to RFC 5280,
-// Section 4.2.1.6 that's correct for an rfc822Name from a certificate: “The
-// format of an rfc822Name is a "Mailbox" as defined in RFC 2821, Section 4.1.2”.
-func parseRFC2821Mailbox(in string) (mailbox rfc2821Mailbox, ok bool) {
-	if len(in) == 0 {
-		return mailbox, false
-	}
-
-	localPartBytes := make([]byte, 0, len(in)/2)
-
-	if in[0] == '"' {
-		// Quoted-string = DQUOTE *qcontent DQUOTE
-		// non-whitespace-control = %d1-8 / %d11 / %d12 / %d14-31 / %d127
-		// qcontent = qtext / quoted-pair
-		// qtext = non-whitespace-control /
-		//         %d33 / %d35-91 / %d93-126
-		// quoted-pair = ("\" text) / obs-qp
-		// text = %d1-9 / %d11 / %d12 / %d14-127 / obs-text
-		//
-		// (Names beginning with “obs-” are the obsolete syntax from RFC 2822,
-		// Section 4. Since it has been 16 years, we no longer accept that.)
-		in = in[1:]
-	QuotedString:
-		for {
-			if len(in) == 0 {
-				return mailbox, false
-			}
-			c := in[0]
-			in = in[1:]
-
-			switch {
-			case c == '"':
-				break QuotedString
-
-			case c == '\\':
-				// quoted-pair
-				if len(in) == 0 {
-					return mailbox, false
-				}
-				if in[0] == 11 ||
-					in[0] == 12 ||
-					(1 <= in[0] && in[0] <= 9) ||
-					(14 <= in[0] && in[0] <= 127) {
-					localPartBytes = append(localPartBytes, in[0])
-					in = in[1:]
-				} else {
-					return mailbox, false
-				}
-
-			case c == 11 ||
-				c == 12 ||
-				// Space (char 32) is not allowed based on the
-				// BNF, but RFC 3696 gives an example that
-				// assumes that it is. Several “verified”
-				// errata continue to argue about this point.
-				// We choose to accept it.
-				c == 32 ||
-				c == 33 ||
-				c == 127 ||
-				(1 <= c && c <= 8) ||
-				(14 <= c && c <= 31) ||
-				(35 <= c && c <= 91) ||
-				(93 <= c && c <= 126):
-				// qtext
-				localPartBytes = append(localPartBytes, c)
-
-			default:
-				return mailbox, false
-			}
-		}
-	} else {
-		// Atom ("." Atom)*
-	NextChar:
-		for len(in) > 0 {
-			// atext from RFC 2822, Section 3.2.4
-			c := in[0]
-
-			switch {
-			case c == '\\':
-				// Examples given in RFC 3696 suggest that
-				// escaped characters can appear outside of a
-				// quoted string. Several “verified” errata
-				// continue to argue the point. We choose to
-				// accept it.
-				in = in[1:]
-				if len(in) == 0 {
-					return mailbox, false
-				}
-				fallthrough
-
-			case ('0' <= c && c <= '9') ||
-				('a' <= c && c <= 'z') ||
-				('A' <= c && c <= 'Z') ||
-				c == '!' || c == '#' || c == '$' || c == '%' ||
-				c == '&' || c == '\'' || c == '*' || c == '+' ||
-				c == '-' || c == '/' || c == '=' || c == '?' ||
-				c == '^' || c == '_' || c == '`' || c == '{' ||
-				c == '|' || c == '}' || c == '~' || c == '.':
-				localPartBytes = append(localPartBytes, in[0])
-				in = in[1:]
-
-			default:
-				break NextChar
-			}
-		}
-
-		if len(localPartBytes) == 0 {
-			return mailbox, false
-		}
-
-		// From RFC 3696, Section 3:
-		// “period (".") may also appear, but may not be used to start
-		// or end the local part, nor may two or more consecutive
-		// periods appear.”
-		twoDots := []byte{'.', '.'}
-		if localPartBytes[0] == '.' ||
-			localPartBytes[len(localPartBytes)-1] == '.' ||
-			bytes.Contains(localPartBytes, twoDots) {
-			return mailbox, false
-		}
-	}
-
-	if len(in) == 0 || in[0] != '@' {
-		return mailbox, false
-	}
-	in = in[1:]
-
-	// The RFC species a format for domains, but that's known to be
-	// violated in practice so we accept that anything after an '@' is the
-	// domain part.
-	if _, ok := domainToReverseLabels(in); !ok {
-		return mailbox, false
-	}
-
-	mailbox.local = string(localPartBytes)
-	mailbox.domain = in
-	return mailbox, true
-}
-
-// domainToReverseLabels converts a textual domain name like foo.example.com to
-// the list of labels in reverse order, e.g. ["com", "example", "foo"].
-func domainToReverseLabels(domain string) (reverseLabels []string, ok bool) {
-	for len(domain) > 0 {
-		if i := strings.LastIndexByte(domain, '.'); i == -1 {
-			reverseLabels = append(reverseLabels, domain)
-			domain = ""
-		} else {
-			reverseLabels = append(reverseLabels, domain[i+1:])
-			domain = domain[:i]
-		}
-	}
-
-	if len(reverseLabels) > 0 && len(reverseLabels[0]) == 0 {
-		// An empty label at the end indicates an absolute value.
-		return nil, false
-	}
-
-	for _, label := range reverseLabels {
-		if len(label) == 0 {
-			// Empty labels are otherwise invalid.
-			return nil, false
-		}
-
-		for _, c := range label {
-			if c < 33 || c > 126 {
-				// Invalid character.
-				return nil, false
-			}
-		}
-	}
-
-	return reverseLabels, true
-}
-
-func matchEmailConstraint(mailbox rfc2821Mailbox, constraint string) (bool, error) {
-	// If the constraint contains an @, then it specifies an exact mailbox
-	// name.
-	if strings.Contains(constraint, "@") {
-		constraintMailbox, ok := parseRFC2821Mailbox(constraint)
-		if !ok {
-			return false, fmt.Errorf("x509: internal error: cannot parse constraint %q", constraint)
-		}
-		return mailbox.local == constraintMailbox.local && strings.EqualFold(mailbox.domain, constraintMailbox.domain), nil
-	}
-
-	// Otherwise the constraint is like a DNS constraint of the domain part
-	// of the mailbox.
-	return matchDomainConstraint(mailbox.domain, constraint)
-}
-
-func matchURIConstraint(uri *url.URL, constraint string) (bool, error) {
-	// From RFC 5280, Section 4.2.1.10:
-	// “a uniformResourceIdentifier that does not include an authority
-	// component with a host name specified as a fully qualified domain
-	// name (e.g., if the URI either does not include an authority
-	// component or includes an authority component in which the host name
-	// is specified as an IP address), then the application MUST reject the
-	// certificate.”
-
-	host := uri.Host
-	if len(host) == 0 {
-		return false, fmt.Errorf("URI with empty host (%q) cannot be matched against constraints", uri.String())
-	}
-
-	if strings.Contains(host, ":") && !strings.HasSuffix(host, "]") {
-		var err error
-		host, _, err = net.SplitHostPort(uri.Host)
-		if err != nil {
-			return false, err
-		}
-	}
-
-	if strings.HasPrefix(host, "[") && strings.HasSuffix(host, "]") ||
-		net.ParseIP(host) != nil {
-		return false, fmt.Errorf("URI with IP (%q) cannot be matched against constraints", uri.String())
-	}
-
-	return matchDomainConstraint(host, constraint)
-}
-
-func matchIPConstraint(ip net.IP, constraint *net.IPNet) (bool, error) {
-	if len(ip) != len(constraint.IP) {
-		return false, nil
-	}
-
-	for i := range ip {
-		if mask := constraint.Mask[i]; ip[i]&mask != constraint.IP[i]&mask {
-			return false, nil
-		}
-	}
-
-	return true, nil
-}
-
-func matchDomainConstraint(domain, constraint string) (bool, error) {
-	// The meaning of zero length constraints is not specified, but this
-	// code follows NSS and accepts them as matching everything.
-	if len(constraint) == 0 {
-		return true, nil
-	}
-
-	domainLabels, ok := domainToReverseLabels(domain)
-	if !ok {
-		return false, fmt.Errorf("x509: internal error: cannot parse domain %q", domain)
-	}
-
-	// RFC 5280 says that a leading period in a domain name means that at
-	// least one label must be prepended, but only for URI and email
-	// constraints, not DNS constraints. The code also supports that
-	// behaviour for DNS constraints.
-
-	mustHaveSubdomains := false
-	if constraint[0] == '.' {
-		mustHaveSubdomains = true
-		constraint = constraint[1:]
-	}
-
-	constraintLabels, ok := domainToReverseLabels(constraint)
-	if !ok {
-		return false, fmt.Errorf("x509: internal error: cannot parse domain %q", constraint)
-	}
-
-	if len(domainLabels) < len(constraintLabels) ||
-		(mustHaveSubdomains && len(domainLabels) == len(constraintLabels)) {
-		return false, nil
-	}
-
-	for i, constraintLabel := range constraintLabels {
-		if !strings.EqualFold(constraintLabel, domainLabels[i]) {
-			return false, nil
-		}
-	}
-
-	return true, nil
-}
-
-// checkNameConstraints checks that c permits a child certificate to claim the
-// given name, of type nameType. The argument parsedName contains the parsed
-// form of name, suitable for passing to the match function. The total number
-// of comparisons is tracked in the given count and should not exceed the given
-// limit.
-func (c *Certificate) checkNameConstraints(count *int,
-	maxConstraintComparisons int,
-	nameType string,
-	name string,
-	parsedName any,
-	match func(parsedName, constraint any) (match bool, err error),
-	permitted, excluded any) error {
-
-	excludedValue := reflect.ValueOf(excluded)
-
-	*count += excludedValue.Len()
-	if *count > maxConstraintComparisons {
-		return CertificateInvalidError{c, TooManyConstraints, ""}
-	}
-
-	for i := 0; i < excludedValue.Len(); i++ {
-		constraint := excludedValue.Index(i).Interface()
-		match, err := match(parsedName, constraint)
-		if err != nil {
-			return CertificateInvalidError{c, CANotAuthorizedForThisName, err.Error()}
-		}
-
-		if match {
-			return CertificateInvalidError{c, CANotAuthorizedForThisName, fmt.Sprintf("%s %q is excluded by constraint %q", nameType, name, constraint)}
-		}
-	}
-
-	permittedValue := reflect.ValueOf(permitted)
-
-	*count += permittedValue.Len()
-	if *count > maxConstraintComparisons {
-		return CertificateInvalidError{c, TooManyConstraints, ""}
-	}
-
-	ok := true
-	for i := 0; i < permittedValue.Len(); i++ {
-		constraint := permittedValue.Index(i).Interface()
-
-		var err error
-		if ok, err = match(parsedName, constraint); err != nil {
-			return CertificateInvalidError{c, CANotAuthorizedForThisName, err.Error()}
-		}
-
-		if ok {
-			break
-		}
-	}
-
-	if !ok {
-		return CertificateInvalidError{c, CANotAuthorizedForThisName, fmt.Sprintf("%s %q is not permitted by any constraint", nameType, name)}
-	}
-
-	return nil
-}
-
-// isValid performs validity checks on c given that it is a candidate to append
-// to the chain in currentChain.
-func (c *Certificate) isValid(certType int, currentChain []*Certificate, opts *VerifyOptions) error {
-	if len(c.UnhandledCriticalExtensions) > 0 {
-		return UnhandledCriticalExtension{}
-	}
-
-	if len(currentChain) > 0 {
-		child := currentChain[len(currentChain)-1]
-		if !bytes.Equal(child.RawIssuer, c.RawSubject) {
-			return CertificateInvalidError{c, NameMismatch, ""}
-		}
-	}
-
-	now := opts.CurrentTime
-	if now.IsZero() {
-		now = time.Now()
-	}
-	if now.Before(c.NotBefore) {
-		return CertificateInvalidError{
-			Cert:   c,
-			Reason: Expired,
-			Detail: fmt.Sprintf("current time %s is before %s", now.Format(time.RFC3339), c.NotBefore.Format(time.RFC3339)),
-		}
-	} else if now.After(c.NotAfter) {
-		return CertificateInvalidError{
-			Cert:   c,
-			Reason: Expired,
-			Detail: fmt.Sprintf("current time %s is after %s", now.Format(time.RFC3339), c.NotAfter.Format(time.RFC3339)),
-		}
-	}
-
-	maxConstraintComparisons := opts.MaxConstraintComparisions
-	if maxConstraintComparisons == 0 {
-		maxConstraintComparisons = 250000
-	}
-	comparisonCount := 0
-
-	var leaf *Certificate
-	if certType == intermediateCertificate || certType == rootCertificate {
-		if len(currentChain) == 0 {
-			return errors.New("x509: internal error: empty chain when appending CA cert")
-		}
-		leaf = currentChain[0]
-	}
-
-	if (certType == intermediateCertificate || certType == rootCertificate) &&
-		c.hasNameConstraints() && leaf.hasSANExtension() {
-		err := forEachSAN(leaf.getSANExtension(), func(tag int, data []byte) error {
-			switch tag {
-			case nameTypeEmail:
-				name := string(data)
-				mailbox, ok := parseRFC2821Mailbox(name)
-				if !ok {
-					return fmt.Errorf("x509: cannot parse rfc822Name %q", mailbox)
-				}
-
-				if err := c.checkNameConstraints(&comparisonCount, maxConstraintComparisons, "email address", name, mailbox,
-					func(parsedName, constraint any) (bool, error) {
-						return matchEmailConstraint(parsedName.(rfc2821Mailbox), constraint.(string))
-					}, c.PermittedEmailAddresses, c.ExcludedEmailAddresses); err != nil {
-					return err
-				}
-
-			case nameTypeDNS:
-				name := string(data)
-				if _, ok := domainToReverseLabels(name); !ok {
-					return fmt.Errorf("x509: cannot parse dnsName %q", name)
-				}
-
-				if err := c.checkNameConstraints(&comparisonCount, maxConstraintComparisons, "DNS name", name, name,
-					func(parsedName, constraint any) (bool, error) {
-						return matchDomainConstraint(parsedName.(string), constraint.(string))
-					}, c.PermittedDNSDomains, c.ExcludedDNSDomains); err != nil {
-					return err
-				}
-
-			case nameTypeURI:
-				name := string(data)
-				uri, err := url.Parse(name)
-				if err != nil {
-					return fmt.Errorf("x509: internal error: URI SAN %q failed to parse", name)
-				}
-
-				if err := c.checkNameConstraints(&comparisonCount, maxConstraintComparisons, "URI", name, uri,
-					func(parsedName, constraint any) (bool, error) {
-						return matchURIConstraint(parsedName.(*url.URL), constraint.(string))
-					}, c.PermittedURIDomains, c.ExcludedURIDomains); err != nil {
-					return err
-				}
-
-			case nameTypeIP:
-				ip := net.IP(data)
-				if l := len(ip); l != net.IPv4len && l != net.IPv6len {
-					return fmt.Errorf("x509: internal error: IP SAN %x failed to parse", data)
-				}
-
-				if err := c.checkNameConstraints(&comparisonCount, maxConstraintComparisons, "IP address", ip.String(), ip,
-					func(parsedName, constraint any) (bool, error) {
-						return matchIPConstraint(parsedName.(net.IP), constraint.(*net.IPNet))
-					}, c.PermittedIPRanges, c.ExcludedIPRanges); err != nil {
-					return err
-				}
-
-			default:
-				// Unknown SAN types are ignored.
-			}
-
-			return nil
-		})
-
-		if err != nil {
-			return err
-		}
-	}
-
-	// KeyUsage status flags are ignored. From Engineering Security, Peter
-	// Gutmann: A European government CA marked its signing certificates as
-	// being valid for encryption only, but no-one noticed. Another
-	// European CA marked its signature keys as not being valid for
-	// signatures. A different CA marked its own trusted root certificate
-	// as being invalid for certificate signing. Another national CA
-	// distributed a certificate to be used to encrypt data for the
-	// country’s tax authority that was marked as only being usable for
-	// digital signatures but not for encryption. Yet another CA reversed
-	// the order of the bit flags in the keyUsage due to confusion over
-	// encoding endianness, essentially setting a random keyUsage in
-	// certificates that it issued. Another CA created a self-invalidating
-	// certificate by adding a certificate policy statement stipulating
-	// that the certificate had to be used strictly as specified in the
-	// keyUsage, and a keyUsage containing a flag indicating that the RSA
-	// encryption key could only be used for Diffie-Hellman key agreement.
-
-	if certType == intermediateCertificate && (!c.BasicConstraintsValid || !c.IsCA) {
-		return CertificateInvalidError{c, NotAuthorizedToSign, ""}
-	}
-
-	if c.BasicConstraintsValid && c.MaxPathLen >= 0 {
-		numIntermediates := len(currentChain) - 1
-		if numIntermediates > c.MaxPathLen {
-			return CertificateInvalidError{c, TooManyIntermediates, ""}
-		}
-	}
-
-	return nil
-}
-
-// Verify attempts to verify c by building one or more chains from c to a
-// certificate in opts.Roots, using certificates in opts.Intermediates if
-// needed. If successful, it returns one or more chains where the first
-// element of the chain is c and the last element is from opts.Roots.
-//
-// If opts.Roots is nil, the platform verifier might be used, and
-// verification details might differ from what is described below. If system
-// roots are unavailable the returned error will be of type SystemRootsError.
-//
-// Name constraints in the intermediates will be applied to all names claimed
-// in the chain, not just opts.DNSName. Thus it is invalid for a leaf to claim
-// example.com if an intermediate doesn't permit it, even if example.com is not
-// the name being validated. Note that DirectoryName constraints are not
-// supported.
-//
-// Name constraint validation follows the rules from RFC 5280, with the
-// addition that DNS name constraints may use the leading period format
-// defined for emails and URIs. When a constraint has a leading period
-// it indicates that at least one additional label must be prepended to
-// the constrained name to be considered valid.
-//
-// Extended Key Usage values are enforced nested down a chain, so an intermediate
-// or root that enumerates EKUs prevents a leaf from asserting an EKU not in that
-// list. (While this is not specified, it is common practice in order to limit
-// the types of certificates a CA can issue.)
-//
-// Certificates that use SHA1WithRSA and ECDSAWithSHA1 signatures are not supported,
-// and will not be used to build chains.
-//
-// WARNING: this function doesn't do any revocation checking.
-func (c *Certificate) Verify(opts VerifyOptions) (chains [][]*Certificate, err error) {
-	// Platform-specific verification needs the ASN.1 contents so
-	// this makes the behavior consistent across platforms.
-	if len(c.Raw) == 0 {
-		return nil, errNotParsed
-	}
-	for i := 0; i < opts.Intermediates.len(); i++ {
-		c, err := opts.Intermediates.cert(i)
-		if err != nil {
-			return nil, fmt.Errorf("crypto/x509: error fetching intermediate: %w", err)
-		}
-		if len(c.Raw) == 0 {
-			return nil, errNotParsed
-		}
-	}
-
-	// Use platform verifiers, where available, if Roots is from SystemCertPool.
-	if runtime.GOOS == "windows" || runtime.GOOS == "darwin" || runtime.GOOS == "ios" {
-		if opts.Roots == nil {
-			return c.systemVerify(&opts)
-		}
-		if opts.Roots != nil && opts.Roots.systemPool {
-			platformChains, err := c.systemVerify(&opts)
-			// If the platform verifier succeeded, or there are no additional
-			// roots, return the platform verifier result. Otherwise, continue
-			// with the Go verifier.
-			if err == nil || opts.Roots.len() == 0 {
-				return platformChains, err
-			}
-		}
-	}
-
-	if opts.Roots == nil {
-		opts.Roots = systemRootsPool()
-		if opts.Roots == nil {
-			return nil, SystemRootsError{systemRootsErr}
-		}
-	}
-
-	err = c.isValid(leafCertificate, nil, &opts)
-	if err != nil {
-		return
-	}
-
-	if len(opts.DNSName) > 0 {
-		err = c.VerifyHostname(opts.DNSName)
-		if err != nil {
-			return
-		}
-	}
-
-	var candidateChains [][]*Certificate
-	if opts.Roots.contains(c) {
-		candidateChains = append(candidateChains, []*Certificate{c})
-	} else {
-		if candidateChains, err = c.buildChains(nil, []*Certificate{c}, nil, &opts); err != nil {
-			return nil, err
-		}
-	}
-
-	keyUsages := opts.KeyUsages
-	if len(keyUsages) == 0 {
-		keyUsages = []ExtKeyUsage{ExtKeyUsageServerAuth}
-	}
-
-	// If any key usage is acceptable then we're done.
-	for _, usage := range keyUsages {
-		if usage == ExtKeyUsageAny {
-			return candidateChains, nil
-		}
-	}
-
-	for _, candidate := range candidateChains {
-		if checkChainForKeyUsage(candidate, keyUsages) {
-			chains = append(chains, candidate)
-		}
-	}
-
-	if len(chains) == 0 {
-		return nil, CertificateInvalidError{c, IncompatibleUsage, ""}
-	}
-
-	return chains, nil
-}
-
-func appendToFreshChain(chain []*Certificate, cert *Certificate) []*Certificate {
-	n := make([]*Certificate, len(chain)+1)
-	copy(n, chain)
-	n[len(chain)] = cert
-	return n
-}
-
-// maxChainSignatureChecks is the maximum number of CheckSignatureFrom calls
-// that an invocation of buildChains will (transitively) make. Most chains are
-// less than 15 certificates long, so this leaves space for multiple chains and
-// for failed checks due to different intermediates having the same Subject.
-const maxChainSignatureChecks = 100
-
-func (c *Certificate) buildChains(cache map[*Certificate][][]*Certificate, currentChain []*Certificate, sigChecks *int, opts *VerifyOptions) (chains [][]*Certificate, err error) {
-	var (
-		hintErr  error
-		hintCert *Certificate
-	)
-
-	considerCandidate := func(certType int, candidate *Certificate) {
-		for _, cert := range currentChain {
-			if cert.Equal(candidate) {
-				return
-			}
-		}
-
-		if sigChecks == nil {
-			sigChecks = new(int)
-		}
-		*sigChecks++
-		if *sigChecks > maxChainSignatureChecks {
-			err = errors.New("x509: signature check attempts limit reached while verifying certificate chain")
-			return
-		}
-
-		if err := c.CheckSignatureFrom(candidate); err != nil {
-			if hintErr == nil {
-				hintErr = err
-				hintCert = candidate
-			}
-			return
-		}
-
-		err = candidate.isValid(certType, currentChain, opts)
-		if err != nil {
-			return
-		}
-
-		switch certType {
-		case rootCertificate:
-			chains = append(chains, appendToFreshChain(currentChain, candidate))
-		case intermediateCertificate:
-			if cache == nil {
-				cache = make(map[*Certificate][][]*Certificate)
-			}
-			childChains, ok := cache[candidate]
-			if !ok {
-				childChains, err = candidate.buildChains(cache, appendToFreshChain(currentChain, candidate), sigChecks, opts)
-				cache[candidate] = childChains
-			}
-			chains = append(chains, childChains...)
-		}
-	}
-
-	for _, root := range opts.Roots.findPotentialParents(c) {
-		considerCandidate(rootCertificate, root)
-	}
-	for _, intermediate := range opts.Intermediates.findPotentialParents(c) {
-		considerCandidate(intermediateCertificate, intermediate)
-	}
-
-	if len(chains) > 0 {
-		err = nil
-	}
-	if len(chains) == 0 && err == nil {
-		err = UnknownAuthorityError{c, hintErr, hintCert}
-	}
-
-	return
-}
-
-func validHostnamePattern(host string) bool { return validHostname(host, true) }
-func validHostnameInput(host string) bool   { return validHostname(host, false) }
-
-// validHostname reports whether host is a valid hostname that can be matched or
-// matched against according to RFC 6125 2.2, with some leniency to accommodate
-// legacy values.
-func validHostname(host string, isPattern bool) bool {
-	if !isPattern {
-		host = strings.TrimSuffix(host, ".")
-	}
-	if len(host) == 0 {
-		return false
-	}
-
-	for i, part := range strings.Split(host, ".") {
-		if part == "" {
-			// Empty label.
-			return false
-		}
-		if isPattern && i == 0 && part == "*" {
-			// Only allow full left-most wildcards, as those are the only ones
-			// we match, and matching literal '*' characters is probably never
-			// the expected behavior.
-			continue
-		}
-		for j, c := range part {
-			if 'a' <= c && c <= 'z' {
-				continue
-			}
-			if '0' <= c && c <= '9' {
-				continue
-			}
-			if 'A' <= c && c <= 'Z' {
-				continue
-			}
-			if c == '-' && j != 0 {
-				continue
-			}
-			if c == '_' {
-				// Not a valid character in hostnames, but commonly
-				// found in deployments outside the WebPKI.
-				continue
-			}
-			return false
-		}
-	}
-
-	return true
-}
-
-func matchExactly(hostA, hostB string) bool {
-	if hostA == "" || hostA == "." || hostB == "" || hostB == "." {
-		return false
-	}
-	return toLowerCaseASCII(hostA) == toLowerCaseASCII(hostB)
-}
-
-func matchHostnames(pattern, host string) bool {
-	pattern = toLowerCaseASCII(pattern)
-	host = toLowerCaseASCII(strings.TrimSuffix(host, "."))
-
-	if len(pattern) == 0 || len(host) == 0 {
-		return false
-	}
-
-	patternParts := strings.Split(pattern, ".")
-	hostParts := strings.Split(host, ".")
-
-	if len(patternParts) != len(hostParts) {
-		return false
-	}
-
-	for i, patternPart := range patternParts {
-		if i == 0 && patternPart == "*" {
-			continue
-		}
-		if patternPart != hostParts[i] {
-			return false
-		}
-	}
-
-	return true
-}
-
-// toLowerCaseASCII returns a lower-case version of in. See RFC 6125 6.4.1. We use
-// an explicitly ASCII function to avoid any sharp corners resulting from
-// performing Unicode operations on DNS labels.
-func toLowerCaseASCII(in string) string {
-	// If the string is already lower-case then there's nothing to do.
-	isAlreadyLowerCase := true
-	for _, c := range in {
-		if c == utf8.RuneError {
-			// If we get a UTF-8 error then there might be
-			// upper-case ASCII bytes in the invalid sequence.
-			isAlreadyLowerCase = false
-			break
-		}
-		if 'A' <= c && c <= 'Z' {
-			isAlreadyLowerCase = false
-			break
-		}
-	}
-
-	if isAlreadyLowerCase {
-		return in
-	}
-
-	out := []byte(in)
-	for i, c := range out {
-		if 'A' <= c && c <= 'Z' {
-			out[i] += 'a' - 'A'
-		}
-	}
-	return string(out)
-}
-
-// VerifyHostname returns nil if c is a valid certificate for the named host.
-// Otherwise it returns an error describing the mismatch.
-//
-// IP addresses can be optionally enclosed in square brackets and are checked
-// against the IPAddresses field. Other names are checked case insensitively
-// against the DNSNames field. If the names are valid hostnames, the certificate
-// fields can have a wildcard as the left-most label.
-//
-// Note that the legacy Common Name field is ignored.
-func (c *Certificate) VerifyHostname(h string) error {
-	// IP addresses may be written in [ ].
-	candidateIP := h
-	if len(h) >= 3 && h[0] == '[' && h[len(h)-1] == ']' {
-		candidateIP = h[1 : len(h)-1]
-	}
-	if ip := net.ParseIP(candidateIP); ip != nil {
-		// We only match IP addresses against IP SANs.
-		// See RFC 6125, Appendix B.2.
-		for _, candidate := range c.IPAddresses {
-			if ip.Equal(candidate) {
-				return nil
-			}
-		}
-		return HostnameError{c, candidateIP}
-	}
-
-	candidateName := toLowerCaseASCII(h) // Save allocations inside the loop.
-	validCandidateName := validHostnameInput(candidateName)
-
-	for _, match := range c.DNSNames {
-		// Ideally, we'd only match valid hostnames according to RFC 6125 like
-		// browsers (more or less) do, but in practice Go is used in a wider
-		// array of contexts and can't even assume DNS resolution. Instead,
-		// always allow perfect matches, and only apply wildcard and trailing
-		// dot processing to valid hostnames.
-		if validCandidateName && validHostnamePattern(match) {
-			if matchHostnames(match, candidateName) {
-				return nil
-			}
-		} else {
-			if matchExactly(match, candidateName) {
-				return nil
-			}
-		}
-	}
-
-	return HostnameError{c, h}
-}
-
-func checkChainForKeyUsage(chain []*Certificate, keyUsages []ExtKeyUsage) bool {
-	usages := make([]ExtKeyUsage, len(keyUsages))
-	copy(usages, keyUsages)
-
-	if len(chain) == 0 {
-		return false
-	}
-
-	usagesRemaining := len(usages)
-
-	// We walk down the list and cross out any usages that aren't supported
-	// by each certificate. If we cross out all the usages, then the chain
-	// is unacceptable.
-
-NextCert:
-	for i := len(chain) - 1; i >= 0; i-- {
-		cert := chain[i]
-		if len(cert.ExtKeyUsage) == 0 && len(cert.UnknownExtKeyUsage) == 0 {
-			// The certificate doesn't have any extended key usage specified.
-			continue
-		}
-
-		for _, usage := range cert.ExtKeyUsage {
-			if usage == ExtKeyUsageAny {
-				// The certificate is explicitly good for any usage.
-				continue NextCert
-			}
-		}
-
-		const invalidUsage ExtKeyUsage = -1
-
-	NextRequestedUsage:
-		for i, requestedUsage := range usages {
-			if requestedUsage == invalidUsage {
-				continue
-			}
-
-			for _, usage := range cert.ExtKeyUsage {
-				if requestedUsage == usage {
-					continue NextRequestedUsage
-				}
-			}
-
-			usages[i] = invalidUsage
-			usagesRemaining--
-			if usagesRemaining == 0 {
-				return false
-			}
-		}
-	}
-
-	return true
-}
diff --git a/contrib/go/_std_1.18/src/crypto/x509/x509.go b/contrib/go/_std_1.18/src/crypto/x509/x509.go
deleted file mode 100644
index 85720b3ccb..0000000000
--- a/contrib/go/_std_1.18/src/crypto/x509/x509.go
+++ /dev/null
@@ -1,2224 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package x509 parses X.509-encoded keys and certificates.
-package x509
-
-import (
-	"bytes"
-	"crypto"
-	"crypto/ecdsa"
-	"crypto/ed25519"
-	"crypto/elliptic"
-	"crypto/rsa"
-	"crypto/sha1"
-	"crypto/x509/pkix"
-	"encoding/asn1"
-	"encoding/pem"
-	"errors"
-	"fmt"
-	"internal/godebug"
-	"io"
-	"math/big"
-	"net"
-	"net/url"
-	"strconv"
-	"time"
-	"unicode"
-
-	// Explicitly import these for their crypto.RegisterHash init side-effects.
-	// Keep these as blank imports, even if they're imported above.
-	_ "crypto/sha1"
-	_ "crypto/sha256"
-	_ "crypto/sha512"
-
-	"golang.org/x/crypto/cryptobyte"
-	cryptobyte_asn1 "golang.org/x/crypto/cryptobyte/asn1"
-)
-
-// pkixPublicKey reflects a PKIX public key structure. See SubjectPublicKeyInfo
-// in RFC 3280.
-type pkixPublicKey struct {
-	Algo      pkix.AlgorithmIdentifier
-	BitString asn1.BitString
-}
-
-// ParsePKIXPublicKey parses a public key in PKIX, ASN.1 DER form.
-// The encoded public key is a SubjectPublicKeyInfo structure
-// (see RFC 5280, Section 4.1).
-//
-// It returns a *rsa.PublicKey, *dsa.PublicKey, *ecdsa.PublicKey, or
-// ed25519.PublicKey. More types might be supported in the future.
-//
-// This kind of key is commonly encoded in PEM blocks of type "PUBLIC KEY".
-func ParsePKIXPublicKey(derBytes []byte) (pub any, err error) {
-	var pki publicKeyInfo
-	if rest, err := asn1.Unmarshal(derBytes, &pki); err != nil {
-		if _, err := asn1.Unmarshal(derBytes, &pkcs1PublicKey{}); err == nil {
-			return nil, errors.New("x509: failed to parse public key (use ParsePKCS1PublicKey instead for this key format)")
-		}
-		return nil, err
-	} else if len(rest) != 0 {
-		return nil, errors.New("x509: trailing data after ASN.1 of public-key")
-	}
-	algo := getPublicKeyAlgorithmFromOID(pki.Algorithm.Algorithm)
-	if algo == UnknownPublicKeyAlgorithm {
-		return nil, errors.New("x509: unknown public key algorithm")
-	}
-	return parsePublicKey(algo, &pki)
-}
-
-func marshalPublicKey(pub any) (publicKeyBytes []byte, publicKeyAlgorithm pkix.AlgorithmIdentifier, err error) {
-	switch pub := pub.(type) {
-	case *rsa.PublicKey:
-		publicKeyBytes, err = asn1.Marshal(pkcs1PublicKey{
-			N: pub.N,
-			E: pub.E,
-		})
-		if err != nil {
-			return nil, pkix.AlgorithmIdentifier{}, err
-		}
-		publicKeyAlgorithm.Algorithm = oidPublicKeyRSA
-		// This is a NULL parameters value which is required by
-		// RFC 3279, Section 2.3.1.
-		publicKeyAlgorithm.Parameters = asn1.NullRawValue
-	case *ecdsa.PublicKey:
-		publicKeyBytes = elliptic.Marshal(pub.Curve, pub.X, pub.Y)
-		oid, ok := oidFromNamedCurve(pub.Curve)
-		if !ok {
-			return nil, pkix.AlgorithmIdentifier{}, errors.New("x509: unsupported elliptic curve")
-		}
-		publicKeyAlgorithm.Algorithm = oidPublicKeyECDSA
-		var paramBytes []byte
-		paramBytes, err = asn1.Marshal(oid)
-		if err != nil {
-			return
-		}
-		publicKeyAlgorithm.Parameters.FullBytes = paramBytes
-	case ed25519.PublicKey:
-		publicKeyBytes = pub
-		publicKeyAlgorithm.Algorithm = oidPublicKeyEd25519
-	default:
-		return nil, pkix.AlgorithmIdentifier{}, fmt.Errorf("x509: unsupported public key type: %T", pub)
-	}
-
-	return publicKeyBytes, publicKeyAlgorithm, nil
-}
-
-// MarshalPKIXPublicKey converts a public key to PKIX, ASN.1 DER form.
-// The encoded public key is a SubjectPublicKeyInfo structure
-// (see RFC 5280, Section 4.1).
-//
-// The following key types are currently supported: *rsa.PublicKey, *ecdsa.PublicKey
-// and ed25519.PublicKey. Unsupported key types result in an error.
-//
-// This kind of key is commonly encoded in PEM blocks of type "PUBLIC KEY".
-func MarshalPKIXPublicKey(pub any) ([]byte, error) {
-	var publicKeyBytes []byte
-	var publicKeyAlgorithm pkix.AlgorithmIdentifier
-	var err error
-
-	if publicKeyBytes, publicKeyAlgorithm, err = marshalPublicKey(pub); err != nil {
-		return nil, err
-	}
-
-	pkix := pkixPublicKey{
-		Algo: publicKeyAlgorithm,
-		BitString: asn1.BitString{
-			Bytes:     publicKeyBytes,
-			BitLength: 8 * len(publicKeyBytes),
-		},
-	}
-
-	ret, _ := asn1.Marshal(pkix)
-	return ret, nil
-}
-
-// These structures reflect the ASN.1 structure of X.509 certificates.:
-
-type certificate struct {
-	Raw                asn1.RawContent
-	TBSCertificate     tbsCertificate
-	SignatureAlgorithm pkix.AlgorithmIdentifier
-	SignatureValue     asn1.BitString
-}
-
-type tbsCertificate struct {
-	Raw                asn1.RawContent
-	Version            int `asn1:"optional,explicit,default:0,tag:0"`
-	SerialNumber       *big.Int
-	SignatureAlgorithm pkix.AlgorithmIdentifier
-	Issuer             asn1.RawValue
-	Validity           validity
-	Subject            asn1.RawValue
-	PublicKey          publicKeyInfo
-	UniqueId           asn1.BitString   `asn1:"optional,tag:1"`
-	SubjectUniqueId    asn1.BitString   `asn1:"optional,tag:2"`
-	Extensions         []pkix.Extension `asn1:"optional,explicit,tag:3"`
-}
-
-type dsaAlgorithmParameters struct {
-	P, Q, G *big.Int
-}
-
-type validity struct {
-	NotBefore, NotAfter time.Time
-}
-
-type publicKeyInfo struct {
-	Raw       asn1.RawContent
-	Algorithm pkix.AlgorithmIdentifier
-	PublicKey asn1.BitString
-}
-
-// RFC 5280,  4.2.1.1
-type authKeyId struct {
-	Id []byte `asn1:"optional,tag:0"`
-}
-
-type SignatureAlgorithm int
-
-const (
-	UnknownSignatureAlgorithm SignatureAlgorithm = iota
-
-	MD2WithRSA  // Unsupported.
-	MD5WithRSA  // Only supported for signing, not verification.
-	SHA1WithRSA // Only supported for signing, and verification of CRLs, CSRs, and OCSP responses.
-	SHA256WithRSA
-	SHA384WithRSA
-	SHA512WithRSA
-	DSAWithSHA1   // Unsupported.
-	DSAWithSHA256 // Unsupported.
-	ECDSAWithSHA1 // Only supported for signing, and verification of CRLs, CSRs, and OCSP responses.
-	ECDSAWithSHA256
-	ECDSAWithSHA384
-	ECDSAWithSHA512
-	SHA256WithRSAPSS
-	SHA384WithRSAPSS
-	SHA512WithRSAPSS
-	PureEd25519
-)
-
-func (algo SignatureAlgorithm) isRSAPSS() bool {
-	switch algo {
-	case SHA256WithRSAPSS, SHA384WithRSAPSS, SHA512WithRSAPSS:
-		return true
-	default:
-		return false
-	}
-}
-
-func (algo SignatureAlgorithm) String() string {
-	for _, details := range signatureAlgorithmDetails {
-		if details.algo == algo {
-			return details.name
-		}
-	}
-	return strconv.Itoa(int(algo))
-}
-
-type PublicKeyAlgorithm int
-
-const (
-	UnknownPublicKeyAlgorithm PublicKeyAlgorithm = iota
-	RSA
-	DSA // Unsupported.
-	ECDSA
-	Ed25519
-)
-
-var publicKeyAlgoName = [...]string{
-	RSA:     "RSA",
-	DSA:     "DSA",
-	ECDSA:   "ECDSA",
-	Ed25519: "Ed25519",
-}
-
-func (algo PublicKeyAlgorithm) String() string {
-	if 0 < algo && int(algo) < len(publicKeyAlgoName) {
-		return publicKeyAlgoName[algo]
-	}
-	return strconv.Itoa(int(algo))
-}
-
-// OIDs for signature algorithms
-//
-// pkcs-1 OBJECT IDENTIFIER ::= {
-//    iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) 1 }
-//
-//
-// RFC 3279 2.2.1 RSA Signature Algorithms
-//
-// md2WithRSAEncryption OBJECT IDENTIFIER ::= { pkcs-1 2 }
-//
-// md5WithRSAEncryption OBJECT IDENTIFIER ::= { pkcs-1 4 }
-//
-// sha-1WithRSAEncryption OBJECT IDENTIFIER ::= { pkcs-1 5 }
-//
-// dsaWithSha1 OBJECT IDENTIFIER ::= {
-//    iso(1) member-body(2) us(840) x9-57(10040) x9cm(4) 3 }
-//
-// RFC 3279 2.2.3 ECDSA Signature Algorithm
-//
-// ecdsa-with-SHA1 OBJECT IDENTIFIER ::= {
-// 	  iso(1) member-body(2) us(840) ansi-x962(10045)
-//    signatures(4) ecdsa-with-SHA1(1)}
-//
-//
-// RFC 4055 5 PKCS #1 Version 1.5
-//
-// sha256WithRSAEncryption OBJECT IDENTIFIER ::= { pkcs-1 11 }
-//
-// sha384WithRSAEncryption OBJECT IDENTIFIER ::= { pkcs-1 12 }
-//
-// sha512WithRSAEncryption OBJECT IDENTIFIER ::= { pkcs-1 13 }
-//
-//
-// RFC 5758 3.1 DSA Signature Algorithms
-//
-// dsaWithSha256 OBJECT IDENTIFIER ::= {
-//    joint-iso-ccitt(2) country(16) us(840) organization(1) gov(101)
-//    csor(3) algorithms(4) id-dsa-with-sha2(3) 2}
-//
-// RFC 5758 3.2 ECDSA Signature Algorithm
-//
-// ecdsa-with-SHA256 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
-//    us(840) ansi-X9-62(10045) signatures(4) ecdsa-with-SHA2(3) 2 }
-//
-// ecdsa-with-SHA384 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
-//    us(840) ansi-X9-62(10045) signatures(4) ecdsa-with-SHA2(3) 3 }
-//
-// ecdsa-with-SHA512 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
-//    us(840) ansi-X9-62(10045) signatures(4) ecdsa-with-SHA2(3) 4 }
-//
-//
-// RFC 8410 3 Curve25519 and Curve448 Algorithm Identifiers
-//
-// id-Ed25519   OBJECT IDENTIFIER ::= { 1 3 101 112 }
-
-var (
-	oidSignatureMD2WithRSA      = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 2}
-	oidSignatureMD5WithRSA      = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 4}
-	oidSignatureSHA1WithRSA     = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 5}
-	oidSignatureSHA256WithRSA   = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 11}
-	oidSignatureSHA384WithRSA   = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 12}
-	oidSignatureSHA512WithRSA   = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 13}
-	oidSignatureRSAPSS          = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 10}
-	oidSignatureDSAWithSHA1     = asn1.ObjectIdentifier{1, 2, 840, 10040, 4, 3}
-	oidSignatureDSAWithSHA256   = asn1.ObjectIdentifier{2, 16, 840, 1, 101, 3, 4, 3, 2}
-	oidSignatureECDSAWithSHA1   = asn1.ObjectIdentifier{1, 2, 840, 10045, 4, 1}
-	oidSignatureECDSAWithSHA256 = asn1.ObjectIdentifier{1, 2, 840, 10045, 4, 3, 2}
-	oidSignatureECDSAWithSHA384 = asn1.ObjectIdentifier{1, 2, 840, 10045, 4, 3, 3}
-	oidSignatureECDSAWithSHA512 = asn1.ObjectIdentifier{1, 2, 840, 10045, 4, 3, 4}
-	oidSignatureEd25519         = asn1.ObjectIdentifier{1, 3, 101, 112}
-
-	oidSHA256 = asn1.ObjectIdentifier{2, 16, 840, 1, 101, 3, 4, 2, 1}
-	oidSHA384 = asn1.ObjectIdentifier{2, 16, 840, 1, 101, 3, 4, 2, 2}
-	oidSHA512 = asn1.ObjectIdentifier{2, 16, 840, 1, 101, 3, 4, 2, 3}
-
-	oidMGF1 = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 8}
-
-	// oidISOSignatureSHA1WithRSA means the same as oidSignatureSHA1WithRSA
-	// but it's specified by ISO. Microsoft's makecert.exe has been known
-	// to produce certificates with this OID.
-	oidISOSignatureSHA1WithRSA = asn1.ObjectIdentifier{1, 3, 14, 3, 2, 29}
-)
-
-var signatureAlgorithmDetails = []struct {
-	algo       SignatureAlgorithm
-	name       string
-	oid        asn1.ObjectIdentifier
-	pubKeyAlgo PublicKeyAlgorithm
-	hash       crypto.Hash
-}{
-	{MD2WithRSA, "MD2-RSA", oidSignatureMD2WithRSA, RSA, crypto.Hash(0) /* no value for MD2 */},
-	{MD5WithRSA, "MD5-RSA", oidSignatureMD5WithRSA, RSA, crypto.MD5},
-	{SHA1WithRSA, "SHA1-RSA", oidSignatureSHA1WithRSA, RSA, crypto.SHA1},
-	{SHA1WithRSA, "SHA1-RSA", oidISOSignatureSHA1WithRSA, RSA, crypto.SHA1},
-	{SHA256WithRSA, "SHA256-RSA", oidSignatureSHA256WithRSA, RSA, crypto.SHA256},
-	{SHA384WithRSA, "SHA384-RSA", oidSignatureSHA384WithRSA, RSA, crypto.SHA384},
-	{SHA512WithRSA, "SHA512-RSA", oidSignatureSHA512WithRSA, RSA, crypto.SHA512},
-	{SHA256WithRSAPSS, "SHA256-RSAPSS", oidSignatureRSAPSS, RSA, crypto.SHA256},
-	{SHA384WithRSAPSS, "SHA384-RSAPSS", oidSignatureRSAPSS, RSA, crypto.SHA384},
-	{SHA512WithRSAPSS, "SHA512-RSAPSS", oidSignatureRSAPSS, RSA, crypto.SHA512},
-	{DSAWithSHA1, "DSA-SHA1", oidSignatureDSAWithSHA1, DSA, crypto.SHA1},
-	{DSAWithSHA256, "DSA-SHA256", oidSignatureDSAWithSHA256, DSA, crypto.SHA256},
-	{ECDSAWithSHA1, "ECDSA-SHA1", oidSignatureECDSAWithSHA1, ECDSA, crypto.SHA1},
-	{ECDSAWithSHA256, "ECDSA-SHA256", oidSignatureECDSAWithSHA256, ECDSA, crypto.SHA256},
-	{ECDSAWithSHA384, "ECDSA-SHA384", oidSignatureECDSAWithSHA384, ECDSA, crypto.SHA384},
-	{ECDSAWithSHA512, "ECDSA-SHA512", oidSignatureECDSAWithSHA512, ECDSA, crypto.SHA512},
-	{PureEd25519, "Ed25519", oidSignatureEd25519, Ed25519, crypto.Hash(0) /* no pre-hashing */},
-}
-
-// hashToPSSParameters contains the DER encoded RSA PSS parameters for the
-// SHA256, SHA384, and SHA512 hashes as defined in RFC 3447, Appendix A.2.3.
-// The parameters contain the following values:
-//   * hashAlgorithm contains the associated hash identifier with NULL parameters
-//   * maskGenAlgorithm always contains the default mgf1SHA1 identifier
-//   * saltLength contains the length of the associated hash
-//   * trailerField always contains the default trailerFieldBC value
-var hashToPSSParameters = map[crypto.Hash]asn1.RawValue{
-	crypto.SHA256: asn1.RawValue{FullBytes: []byte{48, 52, 160, 15, 48, 13, 6, 9, 96, 134, 72, 1, 101, 3, 4, 2, 1, 5, 0, 161, 28, 48, 26, 6, 9, 42, 134, 72, 134, 247, 13, 1, 1, 8, 48, 13, 6, 9, 96, 134, 72, 1, 101, 3, 4, 2, 1, 5, 0, 162, 3, 2, 1, 32}},
-	crypto.SHA384: asn1.RawValue{FullBytes: []byte{48, 52, 160, 15, 48, 13, 6, 9, 96, 134, 72, 1, 101, 3, 4, 2, 2, 5, 0, 161, 28, 48, 26, 6, 9, 42, 134, 72, 134, 247, 13, 1, 1, 8, 48, 13, 6, 9, 96, 134, 72, 1, 101, 3, 4, 2, 2, 5, 0, 162, 3, 2, 1, 48}},
-	crypto.SHA512: asn1.RawValue{FullBytes: []byte{48, 52, 160, 15, 48, 13, 6, 9, 96, 134, 72, 1, 101, 3, 4, 2, 3, 5, 0, 161, 28, 48, 26, 6, 9, 42, 134, 72, 134, 247, 13, 1, 1, 8, 48, 13, 6, 9, 96, 134, 72, 1, 101, 3, 4, 2, 3, 5, 0, 162, 3, 2, 1, 64}},
-}
-
-// pssParameters reflects the parameters in an AlgorithmIdentifier that
-// specifies RSA PSS. See RFC 3447, Appendix A.2.3.
-type pssParameters struct {
-	// The following three fields are not marked as
-	// optional because the default values specify SHA-1,
-	// which is no longer suitable for use in signatures.
-	Hash         pkix.AlgorithmIdentifier `asn1:"explicit,tag:0"`
-	MGF          pkix.AlgorithmIdentifier `asn1:"explicit,tag:1"`
-	SaltLength   int                      `asn1:"explicit,tag:2"`
-	TrailerField int                      `asn1:"optional,explicit,tag:3,default:1"`
-}
-
-func getSignatureAlgorithmFromAI(ai pkix.AlgorithmIdentifier) SignatureAlgorithm {
-	if ai.Algorithm.Equal(oidSignatureEd25519) {
-		// RFC 8410, Section 3
-		// > For all of the OIDs, the parameters MUST be absent.
-		if len(ai.Parameters.FullBytes) != 0 {
-			return UnknownSignatureAlgorithm
-		}
-	}
-
-	if !ai.Algorithm.Equal(oidSignatureRSAPSS) {
-		for _, details := range signatureAlgorithmDetails {
-			if ai.Algorithm.Equal(details.oid) {
-				return details.algo
-			}
-		}
-		return UnknownSignatureAlgorithm
-	}
-
-	// RSA PSS is special because it encodes important parameters
-	// in the Parameters.
-
-	var params pssParameters
-	if _, err := asn1.Unmarshal(ai.Parameters.FullBytes, &params); err != nil {
-		return UnknownSignatureAlgorithm
-	}
-
-	var mgf1HashFunc pkix.AlgorithmIdentifier
-	if _, err := asn1.Unmarshal(params.MGF.Parameters.FullBytes, &mgf1HashFunc); err != nil {
-		return UnknownSignatureAlgorithm
-	}
-
-	// PSS is greatly overburdened with options. This code forces them into
-	// three buckets by requiring that the MGF1 hash function always match the
-	// message hash function (as recommended in RFC 3447, Section 8.1), that the
-	// salt length matches the hash length, and that the trailer field has the
-	// default value.
-	if (len(params.Hash.Parameters.FullBytes) != 0 && !bytes.Equal(params.Hash.Parameters.FullBytes, asn1.NullBytes)) ||
-		!params.MGF.Algorithm.Equal(oidMGF1) ||
-		!mgf1HashFunc.Algorithm.Equal(params.Hash.Algorithm) ||
-		(len(mgf1HashFunc.Parameters.FullBytes) != 0 && !bytes.Equal(mgf1HashFunc.Parameters.FullBytes, asn1.NullBytes)) ||
-		params.TrailerField != 1 {
-		return UnknownSignatureAlgorithm
-	}
-
-	switch {
-	case params.Hash.Algorithm.Equal(oidSHA256) && params.SaltLength == 32:
-		return SHA256WithRSAPSS
-	case params.Hash.Algorithm.Equal(oidSHA384) && params.SaltLength == 48:
-		return SHA384WithRSAPSS
-	case params.Hash.Algorithm.Equal(oidSHA512) && params.SaltLength == 64:
-		return SHA512WithRSAPSS
-	}
-
-	return UnknownSignatureAlgorithm
-}
-
-// RFC 3279, 2.3 Public Key Algorithms
-//
-// pkcs-1 OBJECT IDENTIFIER ::== { iso(1) member-body(2) us(840)
-//    rsadsi(113549) pkcs(1) 1 }
-//
-// rsaEncryption OBJECT IDENTIFIER ::== { pkcs1-1 1 }
-//
-// id-dsa OBJECT IDENTIFIER ::== { iso(1) member-body(2) us(840)
-//    x9-57(10040) x9cm(4) 1 }
-//
-// RFC 5480, 2.1.1 Unrestricted Algorithm Identifier and Parameters
-//
-// id-ecPublicKey OBJECT IDENTIFIER ::= {
-//       iso(1) member-body(2) us(840) ansi-X9-62(10045) keyType(2) 1 }
-var (
-	oidPublicKeyRSA     = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 1}
-	oidPublicKeyDSA     = asn1.ObjectIdentifier{1, 2, 840, 10040, 4, 1}
-	oidPublicKeyECDSA   = asn1.ObjectIdentifier{1, 2, 840, 10045, 2, 1}
-	oidPublicKeyEd25519 = oidSignatureEd25519
-)
-
-func getPublicKeyAlgorithmFromOID(oid asn1.ObjectIdentifier) PublicKeyAlgorithm {
-	switch {
-	case oid.Equal(oidPublicKeyRSA):
-		return RSA
-	case oid.Equal(oidPublicKeyDSA):
-		return DSA
-	case oid.Equal(oidPublicKeyECDSA):
-		return ECDSA
-	case oid.Equal(oidPublicKeyEd25519):
-		return Ed25519
-	}
-	return UnknownPublicKeyAlgorithm
-}
-
-// RFC 5480, 2.1.1.1. Named Curve
-//
-// secp224r1 OBJECT IDENTIFIER ::= {
-//   iso(1) identified-organization(3) certicom(132) curve(0) 33 }
-//
-// secp256r1 OBJECT IDENTIFIER ::= {
-//   iso(1) member-body(2) us(840) ansi-X9-62(10045) curves(3)
-//   prime(1) 7 }
-//
-// secp384r1 OBJECT IDENTIFIER ::= {
-//   iso(1) identified-organization(3) certicom(132) curve(0) 34 }
-//
-// secp521r1 OBJECT IDENTIFIER ::= {
-//   iso(1) identified-organization(3) certicom(132) curve(0) 35 }
-//
-// NB: secp256r1 is equivalent to prime256v1
-var (
-	oidNamedCurveP224 = asn1.ObjectIdentifier{1, 3, 132, 0, 33}
-	oidNamedCurveP256 = asn1.ObjectIdentifier{1, 2, 840, 10045, 3, 1, 7}
-	oidNamedCurveP384 = asn1.ObjectIdentifier{1, 3, 132, 0, 34}
-	oidNamedCurveP521 = asn1.ObjectIdentifier{1, 3, 132, 0, 35}
-)
-
-func namedCurveFromOID(oid asn1.ObjectIdentifier) elliptic.Curve {
-	switch {
-	case oid.Equal(oidNamedCurveP224):
-		return elliptic.P224()
-	case oid.Equal(oidNamedCurveP256):
-		return elliptic.P256()
-	case oid.Equal(oidNamedCurveP384):
-		return elliptic.P384()
-	case oid.Equal(oidNamedCurveP521):
-		return elliptic.P521()
-	}
-	return nil
-}
-
-func oidFromNamedCurve(curve elliptic.Curve) (asn1.ObjectIdentifier, bool) {
-	switch curve {
-	case elliptic.P224():
-		return oidNamedCurveP224, true
-	case elliptic.P256():
-		return oidNamedCurveP256, true
-	case elliptic.P384():
-		return oidNamedCurveP384, true
-	case elliptic.P521():
-		return oidNamedCurveP521, true
-	}
-
-	return nil, false
-}
-
-// KeyUsage represents the set of actions that are valid for a given key. It's
-// a bitmap of the KeyUsage* constants.
-type KeyUsage int
-
-const (
-	KeyUsageDigitalSignature KeyUsage = 1 << iota
-	KeyUsageContentCommitment
-	KeyUsageKeyEncipherment
-	KeyUsageDataEncipherment
-	KeyUsageKeyAgreement
-	KeyUsageCertSign
-	KeyUsageCRLSign
-	KeyUsageEncipherOnly
-	KeyUsageDecipherOnly
-)
-
-// RFC 5280, 4.2.1.12  Extended Key Usage
-//
-// anyExtendedKeyUsage OBJECT IDENTIFIER ::= { id-ce-extKeyUsage 0 }
-//
-// id-kp OBJECT IDENTIFIER ::= { id-pkix 3 }
-//
-// id-kp-serverAuth             OBJECT IDENTIFIER ::= { id-kp 1 }
-// id-kp-clientAuth             OBJECT IDENTIFIER ::= { id-kp 2 }
-// id-kp-codeSigning            OBJECT IDENTIFIER ::= { id-kp 3 }
-// id-kp-emailProtection        OBJECT IDENTIFIER ::= { id-kp 4 }
-// id-kp-timeStamping           OBJECT IDENTIFIER ::= { id-kp 8 }
-// id-kp-OCSPSigning            OBJECT IDENTIFIER ::= { id-kp 9 }
-var (
-	oidExtKeyUsageAny                            = asn1.ObjectIdentifier{2, 5, 29, 37, 0}
-	oidExtKeyUsageServerAuth                     = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 1}
-	oidExtKeyUsageClientAuth                     = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 2}
-	oidExtKeyUsageCodeSigning                    = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 3}
-	oidExtKeyUsageEmailProtection                = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 4}
-	oidExtKeyUsageIPSECEndSystem                 = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 5}
-	oidExtKeyUsageIPSECTunnel                    = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 6}
-	oidExtKeyUsageIPSECUser                      = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 7}
-	oidExtKeyUsageTimeStamping                   = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 8}
-	oidExtKeyUsageOCSPSigning                    = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 9}
-	oidExtKeyUsageMicrosoftServerGatedCrypto     = asn1.ObjectIdentifier{1, 3, 6, 1, 4, 1, 311, 10, 3, 3}
-	oidExtKeyUsageNetscapeServerGatedCrypto      = asn1.ObjectIdentifier{2, 16, 840, 1, 113730, 4, 1}
-	oidExtKeyUsageMicrosoftCommercialCodeSigning = asn1.ObjectIdentifier{1, 3, 6, 1, 4, 1, 311, 2, 1, 22}
-	oidExtKeyUsageMicrosoftKernelCodeSigning     = asn1.ObjectIdentifier{1, 3, 6, 1, 4, 1, 311, 61, 1, 1}
-)
-
-// ExtKeyUsage represents an extended set of actions that are valid for a given key.
-// Each of the ExtKeyUsage* constants define a unique action.
-type ExtKeyUsage int
-
-const (
-	ExtKeyUsageAny ExtKeyUsage = iota
-	ExtKeyUsageServerAuth
-	ExtKeyUsageClientAuth
-	ExtKeyUsageCodeSigning
-	ExtKeyUsageEmailProtection
-	ExtKeyUsageIPSECEndSystem
-	ExtKeyUsageIPSECTunnel
-	ExtKeyUsageIPSECUser
-	ExtKeyUsageTimeStamping
-	ExtKeyUsageOCSPSigning
-	ExtKeyUsageMicrosoftServerGatedCrypto
-	ExtKeyUsageNetscapeServerGatedCrypto
-	ExtKeyUsageMicrosoftCommercialCodeSigning
-	ExtKeyUsageMicrosoftKernelCodeSigning
-)
-
-// extKeyUsageOIDs contains the mapping between an ExtKeyUsage and its OID.
-var extKeyUsageOIDs = []struct {
-	extKeyUsage ExtKeyUsage
-	oid         asn1.ObjectIdentifier
-}{
-	{ExtKeyUsageAny, oidExtKeyUsageAny},
-	{ExtKeyUsageServerAuth, oidExtKeyUsageServerAuth},
-	{ExtKeyUsageClientAuth, oidExtKeyUsageClientAuth},
-	{ExtKeyUsageCodeSigning, oidExtKeyUsageCodeSigning},
-	{ExtKeyUsageEmailProtection, oidExtKeyUsageEmailProtection},
-	{ExtKeyUsageIPSECEndSystem, oidExtKeyUsageIPSECEndSystem},
-	{ExtKeyUsageIPSECTunnel, oidExtKeyUsageIPSECTunnel},
-	{ExtKeyUsageIPSECUser, oidExtKeyUsageIPSECUser},
-	{ExtKeyUsageTimeStamping, oidExtKeyUsageTimeStamping},
-	{ExtKeyUsageOCSPSigning, oidExtKeyUsageOCSPSigning},
-	{ExtKeyUsageMicrosoftServerGatedCrypto, oidExtKeyUsageMicrosoftServerGatedCrypto},
-	{ExtKeyUsageNetscapeServerGatedCrypto, oidExtKeyUsageNetscapeServerGatedCrypto},
-	{ExtKeyUsageMicrosoftCommercialCodeSigning, oidExtKeyUsageMicrosoftCommercialCodeSigning},
-	{ExtKeyUsageMicrosoftKernelCodeSigning, oidExtKeyUsageMicrosoftKernelCodeSigning},
-}
-
-func extKeyUsageFromOID(oid asn1.ObjectIdentifier) (eku ExtKeyUsage, ok bool) {
-	for _, pair := range extKeyUsageOIDs {
-		if oid.Equal(pair.oid) {
-			return pair.extKeyUsage, true
-		}
-	}
-	return
-}
-
-func oidFromExtKeyUsage(eku ExtKeyUsage) (oid asn1.ObjectIdentifier, ok bool) {
-	for _, pair := range extKeyUsageOIDs {
-		if eku == pair.extKeyUsage {
-			return pair.oid, true
-		}
-	}
-	return
-}
-
-// A Certificate represents an X.509 certificate.
-type Certificate struct {
-	Raw                     []byte // Complete ASN.1 DER content (certificate, signature algorithm and signature).
-	RawTBSCertificate       []byte // Certificate part of raw ASN.1 DER content.
-	RawSubjectPublicKeyInfo []byte // DER encoded SubjectPublicKeyInfo.
-	RawSubject              []byte // DER encoded Subject
-	RawIssuer               []byte // DER encoded Issuer
-
-	Signature          []byte
-	SignatureAlgorithm SignatureAlgorithm
-
-	PublicKeyAlgorithm PublicKeyAlgorithm
-	PublicKey          any
-
-	Version             int
-	SerialNumber        *big.Int
-	Issuer              pkix.Name
-	Subject             pkix.Name
-	NotBefore, NotAfter time.Time // Validity bounds.
-	KeyUsage            KeyUsage
-
-	// Extensions contains raw X.509 extensions. When parsing certificates,
-	// this can be used to extract non-critical extensions that are not
-	// parsed by this package. When marshaling certificates, the Extensions
-	// field is ignored, see ExtraExtensions.
-	Extensions []pkix.Extension
-
-	// ExtraExtensions contains extensions to be copied, raw, into any
-	// marshaled certificates. Values override any extensions that would
-	// otherwise be produced based on the other fields. The ExtraExtensions
-	// field is not populated when parsing certificates, see Extensions.
-	ExtraExtensions []pkix.Extension
-
-	// UnhandledCriticalExtensions contains a list of extension IDs that
-	// were not (fully) processed when parsing. Verify will fail if this
-	// slice is non-empty, unless verification is delegated to an OS
-	// library which understands all the critical extensions.
-	//
-	// Users can access these extensions using Extensions and can remove
-	// elements from this slice if they believe that they have been
-	// handled.
-	UnhandledCriticalExtensions []asn1.ObjectIdentifier
-
-	ExtKeyUsage        []ExtKeyUsage           // Sequence of extended key usages.
-	UnknownExtKeyUsage []asn1.ObjectIdentifier // Encountered extended key usages unknown to this package.
-
-	// BasicConstraintsValid indicates whether IsCA, MaxPathLen,
-	// and MaxPathLenZero are valid.
-	BasicConstraintsValid bool
-	IsCA                  bool
-
-	// MaxPathLen and MaxPathLenZero indicate the presence and
-	// value of the BasicConstraints' "pathLenConstraint".
-	//
-	// When parsing a certificate, a positive non-zero MaxPathLen
-	// means that the field was specified, -1 means it was unset,
-	// and MaxPathLenZero being true mean that the field was
-	// explicitly set to zero. The case of MaxPathLen==0 with MaxPathLenZero==false
-	// should be treated equivalent to -1 (unset).
-	//
-	// When generating a certificate, an unset pathLenConstraint
-	// can be requested with either MaxPathLen == -1 or using the
-	// zero value for both MaxPathLen and MaxPathLenZero.
-	MaxPathLen int
-	// MaxPathLenZero indicates that BasicConstraintsValid==true
-	// and MaxPathLen==0 should be interpreted as an actual
-	// maximum path length of zero. Otherwise, that combination is
-	// interpreted as MaxPathLen not being set.
-	MaxPathLenZero bool
-
-	SubjectKeyId   []byte
-	AuthorityKeyId []byte
-
-	// RFC 5280, 4.2.2.1 (Authority Information Access)
-	OCSPServer            []string
-	IssuingCertificateURL []string
-
-	// Subject Alternate Name values. (Note that these values may not be valid
-	// if invalid values were contained within a parsed certificate. For
-	// example, an element of DNSNames may not be a valid DNS domain name.)
-	DNSNames       []string
-	EmailAddresses []string
-	IPAddresses    []net.IP
-	URIs           []*url.URL
-
-	// Name constraints
-	PermittedDNSDomainsCritical bool // if true then the name constraints are marked critical.
-	PermittedDNSDomains         []string
-	ExcludedDNSDomains          []string
-	PermittedIPRanges           []*net.IPNet
-	ExcludedIPRanges            []*net.IPNet
-	PermittedEmailAddresses     []string
-	ExcludedEmailAddresses      []string
-	PermittedURIDomains         []string
-	ExcludedURIDomains          []string
-
-	// CRL Distribution Points
-	CRLDistributionPoints []string
-
-	PolicyIdentifiers []asn1.ObjectIdentifier
-}
-
-// ErrUnsupportedAlgorithm results from attempting to perform an operation that
-// involves algorithms that are not currently implemented.
-var ErrUnsupportedAlgorithm = errors.New("x509: cannot verify signature: algorithm unimplemented")
-
-// debugAllowSHA1 allows SHA-1 signatures. See issue 41682.
-var debugAllowSHA1 = godebug.Get("x509sha1") == "1"
-
-// An InsecureAlgorithmError indicates that the SignatureAlgorithm used to
-// generate the signature is not secure, and the signature has been rejected.
-//
-// To temporarily restore support for SHA-1 signatures, include the value
-// "x509sha1=1" in the GODEBUG environment variable. Note that this option will
-// be removed in Go 1.19.
-type InsecureAlgorithmError SignatureAlgorithm
-
-func (e InsecureAlgorithmError) Error() string {
-	var override string
-	if SignatureAlgorithm(e) == SHA1WithRSA || SignatureAlgorithm(e) == ECDSAWithSHA1 {
-		override = " (temporarily override with GODEBUG=x509sha1=1)"
-	}
-	return fmt.Sprintf("x509: cannot verify signature: insecure algorithm %v", SignatureAlgorithm(e)) + override
-}
-
-// ConstraintViolationError results when a requested usage is not permitted by
-// a certificate. For example: checking a signature when the public key isn't a
-// certificate signing key.
-type ConstraintViolationError struct{}
-
-func (ConstraintViolationError) Error() string {
-	return "x509: invalid signature: parent certificate cannot sign this kind of certificate"
-}
-
-func (c *Certificate) Equal(other *Certificate) bool {
-	if c == nil || other == nil {
-		return c == other
-	}
-	return bytes.Equal(c.Raw, other.Raw)
-}
-
-func (c *Certificate) hasSANExtension() bool {
-	return oidInExtensions(oidExtensionSubjectAltName, c.Extensions)
-}
-
-// CheckSignatureFrom verifies that the signature on c is a valid signature
-// from parent. SHA1WithRSA and ECDSAWithSHA1 signatures are not supported.
-func (c *Certificate) CheckSignatureFrom(parent *Certificate) error {
-	// RFC 5280, 4.2.1.9:
-	// "If the basic constraints extension is not present in a version 3
-	// certificate, or the extension is present but the cA boolean is not
-	// asserted, then the certified public key MUST NOT be used to verify
-	// certificate signatures."
-	if parent.Version == 3 && !parent.BasicConstraintsValid ||
-		parent.BasicConstraintsValid && !parent.IsCA {
-		return ConstraintViolationError{}
-	}
-
-	if parent.KeyUsage != 0 && parent.KeyUsage&KeyUsageCertSign == 0 {
-		return ConstraintViolationError{}
-	}
-
-	if parent.PublicKeyAlgorithm == UnknownPublicKeyAlgorithm {
-		return ErrUnsupportedAlgorithm
-	}
-
-	// TODO(agl): don't ignore the path length constraint.
-
-	return checkSignature(c.SignatureAlgorithm, c.RawTBSCertificate, c.Signature, parent.PublicKey, debugAllowSHA1)
-}
-
-// CheckSignature verifies that signature is a valid signature over signed from
-// c's public key.
-func (c *Certificate) CheckSignature(algo SignatureAlgorithm, signed, signature []byte) error {
-	return checkSignature(algo, signed, signature, c.PublicKey, true)
-}
-
-func (c *Certificate) hasNameConstraints() bool {
-	return oidInExtensions(oidExtensionNameConstraints, c.Extensions)
-}
-
-func (c *Certificate) getSANExtension() []byte {
-	for _, e := range c.Extensions {
-		if e.Id.Equal(oidExtensionSubjectAltName) {
-			return e.Value
-		}
-	}
-	return nil
-}
-
-func signaturePublicKeyAlgoMismatchError(expectedPubKeyAlgo PublicKeyAlgorithm, pubKey any) error {
-	return fmt.Errorf("x509: signature algorithm specifies an %s public key, but have public key of type %T", expectedPubKeyAlgo.String(), pubKey)
-}
-
-// checkSignature verifies that signature is a valid signature over signed from
-// a crypto.PublicKey.
-func checkSignature(algo SignatureAlgorithm, signed, signature []byte, publicKey crypto.PublicKey, allowSHA1 bool) (err error) {
-	var hashType crypto.Hash
-	var pubKeyAlgo PublicKeyAlgorithm
-
-	for _, details := range signatureAlgorithmDetails {
-		if details.algo == algo {
-			hashType = details.hash
-			pubKeyAlgo = details.pubKeyAlgo
-		}
-	}
-
-	switch hashType {
-	case crypto.Hash(0):
-		if pubKeyAlgo != Ed25519 {
-			return ErrUnsupportedAlgorithm
-		}
-	case crypto.MD5:
-		return InsecureAlgorithmError(algo)
-	case crypto.SHA1:
-		if !allowSHA1 {
-			return InsecureAlgorithmError(algo)
-		}
-		fallthrough
-	default:
-		if !hashType.Available() {
-			return ErrUnsupportedAlgorithm
-		}
-		h := hashType.New()
-		h.Write(signed)
-		signed = h.Sum(nil)
-	}
-
-	switch pub := publicKey.(type) {
-	case *rsa.PublicKey:
-		if pubKeyAlgo != RSA {
-			return signaturePublicKeyAlgoMismatchError(pubKeyAlgo, pub)
-		}
-		if algo.isRSAPSS() {
-			return rsa.VerifyPSS(pub, hashType, signed, signature, &rsa.PSSOptions{SaltLength: rsa.PSSSaltLengthEqualsHash})
-		} else {
-			return rsa.VerifyPKCS1v15(pub, hashType, signed, signature)
-		}
-	case *ecdsa.PublicKey:
-		if pubKeyAlgo != ECDSA {
-			return signaturePublicKeyAlgoMismatchError(pubKeyAlgo, pub)
-		}
-		if !ecdsa.VerifyASN1(pub, signed, signature) {
-			return errors.New("x509: ECDSA verification failure")
-		}
-		return
-	case ed25519.PublicKey:
-		if pubKeyAlgo != Ed25519 {
-			return signaturePublicKeyAlgoMismatchError(pubKeyAlgo, pub)
-		}
-		if !ed25519.Verify(pub, signed, signature) {
-			return errors.New("x509: Ed25519 verification failure")
-		}
-		return
-	}
-	return ErrUnsupportedAlgorithm
-}
-
-// CheckCRLSignature checks that the signature in crl is from c.
-func (c *Certificate) CheckCRLSignature(crl *pkix.CertificateList) error {
-	algo := getSignatureAlgorithmFromAI(crl.SignatureAlgorithm)
-	return c.CheckSignature(algo, crl.TBSCertList.Raw, crl.SignatureValue.RightAlign())
-}
-
-type UnhandledCriticalExtension struct{}
-
-func (h UnhandledCriticalExtension) Error() string {
-	return "x509: unhandled critical extension"
-}
-
-type basicConstraints struct {
-	IsCA       bool `asn1:"optional"`
-	MaxPathLen int  `asn1:"optional,default:-1"`
-}
-
-// RFC 5280 4.2.1.4
-type policyInformation struct {
-	Policy asn1.ObjectIdentifier
-	// policyQualifiers omitted
-}
-
-const (
-	nameTypeEmail = 1
-	nameTypeDNS   = 2
-	nameTypeURI   = 6
-	nameTypeIP    = 7
-)
-
-// RFC 5280, 4.2.2.1
-type authorityInfoAccess struct {
-	Method   asn1.ObjectIdentifier
-	Location asn1.RawValue
-}
-
-// RFC 5280, 4.2.1.14
-type distributionPoint struct {
-	DistributionPoint distributionPointName `asn1:"optional,tag:0"`
-	Reason            asn1.BitString        `asn1:"optional,tag:1"`
-	CRLIssuer         asn1.RawValue         `asn1:"optional,tag:2"`
-}
-
-type distributionPointName struct {
-	FullName     []asn1.RawValue  `asn1:"optional,tag:0"`
-	RelativeName pkix.RDNSequence `asn1:"optional,tag:1"`
-}
-
-func reverseBitsInAByte(in byte) byte {
-	b1 := in>>4 | in<<4
-	b2 := b1>>2&0x33 | b1<<2&0xcc
-	b3 := b2>>1&0x55 | b2<<1&0xaa
-	return b3
-}
-
-// asn1BitLength returns the bit-length of bitString by considering the
-// most-significant bit in a byte to be the "first" bit. This convention
-// matches ASN.1, but differs from almost everything else.
-func asn1BitLength(bitString []byte) int {
-	bitLen := len(bitString) * 8
-
-	for i := range bitString {
-		b := bitString[len(bitString)-i-1]
-
-		for bit := uint(0); bit < 8; bit++ {
-			if (b>>bit)&1 == 1 {
-				return bitLen
-			}
-			bitLen--
-		}
-	}
-
-	return 0
-}
-
-var (
-	oidExtensionSubjectKeyId          = []int{2, 5, 29, 14}
-	oidExtensionKeyUsage              = []int{2, 5, 29, 15}
-	oidExtensionExtendedKeyUsage      = []int{2, 5, 29, 37}
-	oidExtensionAuthorityKeyId        = []int{2, 5, 29, 35}
-	oidExtensionBasicConstraints      = []int{2, 5, 29, 19}
-	oidExtensionSubjectAltName        = []int{2, 5, 29, 17}
-	oidExtensionCertificatePolicies   = []int{2, 5, 29, 32}
-	oidExtensionNameConstraints       = []int{2, 5, 29, 30}
-	oidExtensionCRLDistributionPoints = []int{2, 5, 29, 31}
-	oidExtensionAuthorityInfoAccess   = []int{1, 3, 6, 1, 5, 5, 7, 1, 1}
-	oidExtensionCRLNumber             = []int{2, 5, 29, 20}
-)
-
-var (
-	oidAuthorityInfoAccessOcsp    = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 48, 1}
-	oidAuthorityInfoAccessIssuers = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 48, 2}
-)
-
-// oidNotInExtensions reports whether an extension with the given oid exists in
-// extensions.
-func oidInExtensions(oid asn1.ObjectIdentifier, extensions []pkix.Extension) bool {
-	for _, e := range extensions {
-		if e.Id.Equal(oid) {
-			return true
-		}
-	}
-	return false
-}
-
-// marshalSANs marshals a list of addresses into a the contents of an X.509
-// SubjectAlternativeName extension.
-func marshalSANs(dnsNames, emailAddresses []string, ipAddresses []net.IP, uris []*url.URL) (derBytes []byte, err error) {
-	var rawValues []asn1.RawValue
-	for _, name := range dnsNames {
-		if err := isIA5String(name); err != nil {
-			return nil, err
-		}
-		rawValues = append(rawValues, asn1.RawValue{Tag: nameTypeDNS, Class: 2, Bytes: []byte(name)})
-	}
-	for _, email := range emailAddresses {
-		if err := isIA5String(email); err != nil {
-			return nil, err
-		}
-		rawValues = append(rawValues, asn1.RawValue{Tag: nameTypeEmail, Class: 2, Bytes: []byte(email)})
-	}
-	for _, rawIP := range ipAddresses {
-		// If possible, we always want to encode IPv4 addresses in 4 bytes.
-		ip := rawIP.To4()
-		if ip == nil {
-			ip = rawIP
-		}
-		rawValues = append(rawValues, asn1.RawValue{Tag: nameTypeIP, Class: 2, Bytes: ip})
-	}
-	for _, uri := range uris {
-		uriStr := uri.String()
-		if err := isIA5String(uriStr); err != nil {
-			return nil, err
-		}
-		rawValues = append(rawValues, asn1.RawValue{Tag: nameTypeURI, Class: 2, Bytes: []byte(uriStr)})
-	}
-	return asn1.Marshal(rawValues)
-}
-
-func isIA5String(s string) error {
-	for _, r := range s {
-		// Per RFC5280 "IA5String is limited to the set of ASCII characters"
-		if r > unicode.MaxASCII {
-			return fmt.Errorf("x509: %q cannot be encoded as an IA5String", s)
-		}
-	}
-
-	return nil
-}
-
-func buildCertExtensions(template *Certificate, subjectIsEmpty bool, authorityKeyId []byte, subjectKeyId []byte) (ret []pkix.Extension, err error) {
-	ret = make([]pkix.Extension, 10 /* maximum number of elements. */)
-	n := 0
-
-	if template.KeyUsage != 0 &&
-		!oidInExtensions(oidExtensionKeyUsage, template.ExtraExtensions) {
-		ret[n], err = marshalKeyUsage(template.KeyUsage)
-		if err != nil {
-			return nil, err
-		}
-		n++
-	}
-
-	if (len(template.ExtKeyUsage) > 0 || len(template.UnknownExtKeyUsage) > 0) &&
-		!oidInExtensions(oidExtensionExtendedKeyUsage, template.ExtraExtensions) {
-		ret[n], err = marshalExtKeyUsage(template.ExtKeyUsage, template.UnknownExtKeyUsage)
-		if err != nil {
-			return nil, err
-		}
-		n++
-	}
-
-	if template.BasicConstraintsValid && !oidInExtensions(oidExtensionBasicConstraints, template.ExtraExtensions) {
-		ret[n], err = marshalBasicConstraints(template.IsCA, template.MaxPathLen, template.MaxPathLenZero)
-		if err != nil {
-			return nil, err
-		}
-		n++
-	}
-
-	if len(subjectKeyId) > 0 && !oidInExtensions(oidExtensionSubjectKeyId, template.ExtraExtensions) {
-		ret[n].Id = oidExtensionSubjectKeyId
-		ret[n].Value, err = asn1.Marshal(subjectKeyId)
-		if err != nil {
-			return
-		}
-		n++
-	}
-
-	if len(authorityKeyId) > 0 && !oidInExtensions(oidExtensionAuthorityKeyId, template.ExtraExtensions) {
-		ret[n].Id = oidExtensionAuthorityKeyId
-		ret[n].Value, err = asn1.Marshal(authKeyId{authorityKeyId})
-		if err != nil {
-			return
-		}
-		n++
-	}
-
-	if (len(template.OCSPServer) > 0 || len(template.IssuingCertificateURL) > 0) &&
-		!oidInExtensions(oidExtensionAuthorityInfoAccess, template.ExtraExtensions) {
-		ret[n].Id = oidExtensionAuthorityInfoAccess
-		var aiaValues []authorityInfoAccess
-		for _, name := range template.OCSPServer {
-			aiaValues = append(aiaValues, authorityInfoAccess{
-				Method:   oidAuthorityInfoAccessOcsp,
-				Location: asn1.RawValue{Tag: 6, Class: 2, Bytes: []byte(name)},
-			})
-		}
-		for _, name := range template.IssuingCertificateURL {
-			aiaValues = append(aiaValues, authorityInfoAccess{
-				Method:   oidAuthorityInfoAccessIssuers,
-				Location: asn1.RawValue{Tag: 6, Class: 2, Bytes: []byte(name)},
-			})
-		}
-		ret[n].Value, err = asn1.Marshal(aiaValues)
-		if err != nil {
-			return
-		}
-		n++
-	}
-
-	if (len(template.DNSNames) > 0 || len(template.EmailAddresses) > 0 || len(template.IPAddresses) > 0 || len(template.URIs) > 0) &&
-		!oidInExtensions(oidExtensionSubjectAltName, template.ExtraExtensions) {
-		ret[n].Id = oidExtensionSubjectAltName
-		// From RFC 5280, Section 4.2.1.6:
-		// “If the subject field contains an empty sequence ... then
-		// subjectAltName extension ... is marked as critical”
-		ret[n].Critical = subjectIsEmpty
-		ret[n].Value, err = marshalSANs(template.DNSNames, template.EmailAddresses, template.IPAddresses, template.URIs)
-		if err != nil {
-			return
-		}
-		n++
-	}
-
-	if len(template.PolicyIdentifiers) > 0 &&
-		!oidInExtensions(oidExtensionCertificatePolicies, template.ExtraExtensions) {
-		ret[n], err = marshalCertificatePolicies(template.PolicyIdentifiers)
-		if err != nil {
-			return nil, err
-		}
-		n++
-	}
-
-	if (len(template.PermittedDNSDomains) > 0 || len(template.ExcludedDNSDomains) > 0 ||
-		len(template.PermittedIPRanges) > 0 || len(template.ExcludedIPRanges) > 0 ||
-		len(template.PermittedEmailAddresses) > 0 || len(template.ExcludedEmailAddresses) > 0 ||
-		len(template.PermittedURIDomains) > 0 || len(template.ExcludedURIDomains) > 0) &&
-		!oidInExtensions(oidExtensionNameConstraints, template.ExtraExtensions) {
-		ret[n].Id = oidExtensionNameConstraints
-		ret[n].Critical = template.PermittedDNSDomainsCritical
-
-		ipAndMask := func(ipNet *net.IPNet) []byte {
-			maskedIP := ipNet.IP.Mask(ipNet.Mask)
-			ipAndMask := make([]byte, 0, len(maskedIP)+len(ipNet.Mask))
-			ipAndMask = append(ipAndMask, maskedIP...)
-			ipAndMask = append(ipAndMask, ipNet.Mask...)
-			return ipAndMask
-		}
-
-		serialiseConstraints := func(dns []string, ips []*net.IPNet, emails []string, uriDomains []string) (der []byte, err error) {
-			var b cryptobyte.Builder
-
-			for _, name := range dns {
-				if err = isIA5String(name); err != nil {
-					return nil, err
-				}
-
-				b.AddASN1(cryptobyte_asn1.SEQUENCE, func(b *cryptobyte.Builder) {
-					b.AddASN1(cryptobyte_asn1.Tag(2).ContextSpecific(), func(b *cryptobyte.Builder) {
-						b.AddBytes([]byte(name))
-					})
-				})
-			}
-
-			for _, ipNet := range ips {
-				b.AddASN1(cryptobyte_asn1.SEQUENCE, func(b *cryptobyte.Builder) {
-					b.AddASN1(cryptobyte_asn1.Tag(7).ContextSpecific(), func(b *cryptobyte.Builder) {
-						b.AddBytes(ipAndMask(ipNet))
-					})
-				})
-			}
-
-			for _, email := range emails {
-				if err = isIA5String(email); err != nil {
-					return nil, err
-				}
-
-				b.AddASN1(cryptobyte_asn1.SEQUENCE, func(b *cryptobyte.Builder) {
-					b.AddASN1(cryptobyte_asn1.Tag(1).ContextSpecific(), func(b *cryptobyte.Builder) {
-						b.AddBytes([]byte(email))
-					})
-				})
-			}
-
-			for _, uriDomain := range uriDomains {
-				if err = isIA5String(uriDomain); err != nil {
-					return nil, err
-				}
-
-				b.AddASN1(cryptobyte_asn1.SEQUENCE, func(b *cryptobyte.Builder) {
-					b.AddASN1(cryptobyte_asn1.Tag(6).ContextSpecific(), func(b *cryptobyte.Builder) {
-						b.AddBytes([]byte(uriDomain))
-					})
-				})
-			}
-
-			return b.Bytes()
-		}
-
-		permitted, err := serialiseConstraints(template.PermittedDNSDomains, template.PermittedIPRanges, template.PermittedEmailAddresses, template.PermittedURIDomains)
-		if err != nil {
-			return nil, err
-		}
-
-		excluded, err := serialiseConstraints(template.ExcludedDNSDomains, template.ExcludedIPRanges, template.ExcludedEmailAddresses, template.ExcludedURIDomains)
-		if err != nil {
-			return nil, err
-		}
-
-		var b cryptobyte.Builder
-		b.AddASN1(cryptobyte_asn1.SEQUENCE, func(b *cryptobyte.Builder) {
-			if len(permitted) > 0 {
-				b.AddASN1(cryptobyte_asn1.Tag(0).ContextSpecific().Constructed(), func(b *cryptobyte.Builder) {
-					b.AddBytes(permitted)
-				})
-			}
-
-			if len(excluded) > 0 {
-				b.AddASN1(cryptobyte_asn1.Tag(1).ContextSpecific().Constructed(), func(b *cryptobyte.Builder) {
-					b.AddBytes(excluded)
-				})
-			}
-		})
-
-		ret[n].Value, err = b.Bytes()
-		if err != nil {
-			return nil, err
-		}
-		n++
-	}
-
-	if len(template.CRLDistributionPoints) > 0 &&
-		!oidInExtensions(oidExtensionCRLDistributionPoints, template.ExtraExtensions) {
-		ret[n].Id = oidExtensionCRLDistributionPoints
-
-		var crlDp []distributionPoint
-		for _, name := range template.CRLDistributionPoints {
-			dp := distributionPoint{
-				DistributionPoint: distributionPointName{
-					FullName: []asn1.RawValue{
-						{Tag: 6, Class: 2, Bytes: []byte(name)},
-					},
-				},
-			}
-			crlDp = append(crlDp, dp)
-		}
-
-		ret[n].Value, err = asn1.Marshal(crlDp)
-		if err != nil {
-			return
-		}
-		n++
-	}
-
-	// Adding another extension here? Remember to update the maximum number
-	// of elements in the make() at the top of the function and the list of
-	// template fields used in CreateCertificate documentation.
-
-	return append(ret[:n], template.ExtraExtensions...), nil
-}
-
-func marshalKeyUsage(ku KeyUsage) (pkix.Extension, error) {
-	ext := pkix.Extension{Id: oidExtensionKeyUsage, Critical: true}
-
-	var a [2]byte
-	a[0] = reverseBitsInAByte(byte(ku))
-	a[1] = reverseBitsInAByte(byte(ku >> 8))
-
-	l := 1
-	if a[1] != 0 {
-		l = 2
-	}
-
-	bitString := a[:l]
-	var err error
-	ext.Value, err = asn1.Marshal(asn1.BitString{Bytes: bitString, BitLength: asn1BitLength(bitString)})
-	if err != nil {
-		return ext, err
-	}
-	return ext, nil
-}
-
-func marshalExtKeyUsage(extUsages []ExtKeyUsage, unknownUsages []asn1.ObjectIdentifier) (pkix.Extension, error) {
-	ext := pkix.Extension{Id: oidExtensionExtendedKeyUsage}
-
-	oids := make([]asn1.ObjectIdentifier, len(extUsages)+len(unknownUsages))
-	for i, u := range extUsages {
-		if oid, ok := oidFromExtKeyUsage(u); ok {
-			oids[i] = oid
-		} else {
-			return ext, errors.New("x509: unknown extended key usage")
-		}
-	}
-
-	copy(oids[len(extUsages):], unknownUsages)
-
-	var err error
-	ext.Value, err = asn1.Marshal(oids)
-	if err != nil {
-		return ext, err
-	}
-	return ext, nil
-}
-
-func marshalBasicConstraints(isCA bool, maxPathLen int, maxPathLenZero bool) (pkix.Extension, error) {
-	ext := pkix.Extension{Id: oidExtensionBasicConstraints, Critical: true}
-	// Leaving MaxPathLen as zero indicates that no maximum path
-	// length is desired, unless MaxPathLenZero is set. A value of
-	// -1 causes encoding/asn1 to omit the value as desired.
-	if maxPathLen == 0 && !maxPathLenZero {
-		maxPathLen = -1
-	}
-	var err error
-	ext.Value, err = asn1.Marshal(basicConstraints{isCA, maxPathLen})
-	if err != nil {
-		return ext, nil
-	}
-	return ext, nil
-}
-
-func marshalCertificatePolicies(policyIdentifiers []asn1.ObjectIdentifier) (pkix.Extension, error) {
-	ext := pkix.Extension{Id: oidExtensionCertificatePolicies}
-	policies := make([]policyInformation, len(policyIdentifiers))
-	for i, policy := range policyIdentifiers {
-		policies[i].Policy = policy
-	}
-	var err error
-	ext.Value, err = asn1.Marshal(policies)
-	if err != nil {
-		return ext, err
-	}
-	return ext, nil
-}
-
-func buildCSRExtensions(template *CertificateRequest) ([]pkix.Extension, error) {
-	var ret []pkix.Extension
-
-	if (len(template.DNSNames) > 0 || len(template.EmailAddresses) > 0 || len(template.IPAddresses) > 0 || len(template.URIs) > 0) &&
-		!oidInExtensions(oidExtensionSubjectAltName, template.ExtraExtensions) {
-		sanBytes, err := marshalSANs(template.DNSNames, template.EmailAddresses, template.IPAddresses, template.URIs)
-		if err != nil {
-			return nil, err
-		}
-
-		ret = append(ret, pkix.Extension{
-			Id:    oidExtensionSubjectAltName,
-			Value: sanBytes,
-		})
-	}
-
-	return append(ret, template.ExtraExtensions...), nil
-}
-
-func subjectBytes(cert *Certificate) ([]byte, error) {
-	if len(cert.RawSubject) > 0 {
-		return cert.RawSubject, nil
-	}
-
-	return asn1.Marshal(cert.Subject.ToRDNSequence())
-}
-
-// signingParamsForPublicKey returns the parameters to use for signing with
-// priv. If requestedSigAlgo is not zero then it overrides the default
-// signature algorithm.
-func signingParamsForPublicKey(pub any, requestedSigAlgo SignatureAlgorithm) (hashFunc crypto.Hash, sigAlgo pkix.AlgorithmIdentifier, err error) {
-	var pubType PublicKeyAlgorithm
-
-	switch pub := pub.(type) {
-	case *rsa.PublicKey:
-		pubType = RSA
-		hashFunc = crypto.SHA256
-		sigAlgo.Algorithm = oidSignatureSHA256WithRSA
-		sigAlgo.Parameters = asn1.NullRawValue
-
-	case *ecdsa.PublicKey:
-		pubType = ECDSA
-
-		switch pub.Curve {
-		case elliptic.P224(), elliptic.P256():
-			hashFunc = crypto.SHA256
-			sigAlgo.Algorithm = oidSignatureECDSAWithSHA256
-		case elliptic.P384():
-			hashFunc = crypto.SHA384
-			sigAlgo.Algorithm = oidSignatureECDSAWithSHA384
-		case elliptic.P521():
-			hashFunc = crypto.SHA512
-			sigAlgo.Algorithm = oidSignatureECDSAWithSHA512
-		default:
-			err = errors.New("x509: unknown elliptic curve")
-		}
-
-	case ed25519.PublicKey:
-		pubType = Ed25519
-		sigAlgo.Algorithm = oidSignatureEd25519
-
-	default:
-		err = errors.New("x509: only RSA, ECDSA and Ed25519 keys supported")
-	}
-
-	if err != nil {
-		return
-	}
-
-	if requestedSigAlgo == 0 {
-		return
-	}
-
-	found := false
-	for _, details := range signatureAlgorithmDetails {
-		if details.algo == requestedSigAlgo {
-			if details.pubKeyAlgo != pubType {
-				err = errors.New("x509: requested SignatureAlgorithm does not match private key type")
-				return
-			}
-			sigAlgo.Algorithm, hashFunc = details.oid, details.hash
-			if hashFunc == 0 && pubType != Ed25519 {
-				err = errors.New("x509: cannot sign with hash function requested")
-				return
-			}
-			if requestedSigAlgo.isRSAPSS() {
-				sigAlgo.Parameters = hashToPSSParameters[hashFunc]
-			}
-			found = true
-			break
-		}
-	}
-
-	if !found {
-		err = errors.New("x509: unknown SignatureAlgorithm")
-	}
-
-	return
-}
-
-// emptyASN1Subject is the ASN.1 DER encoding of an empty Subject, which is
-// just an empty SEQUENCE.
-var emptyASN1Subject = []byte{0x30, 0}
-
-// CreateCertificate creates a new X.509 v3 certificate based on a template.
-// The following members of template are currently used:
-//
-//  - AuthorityKeyId
-//  - BasicConstraintsValid
-//  - CRLDistributionPoints
-//  - DNSNames
-//  - EmailAddresses
-//  - ExcludedDNSDomains
-//  - ExcludedEmailAddresses
-//  - ExcludedIPRanges
-//  - ExcludedURIDomains
-//  - ExtKeyUsage
-//  - ExtraExtensions
-//  - IPAddresses
-//  - IsCA
-//  - IssuingCertificateURL
-//  - KeyUsage
-//  - MaxPathLen
-//  - MaxPathLenZero
-//  - NotAfter
-//  - NotBefore
-//  - OCSPServer
-//  - PermittedDNSDomains
-//  - PermittedDNSDomainsCritical
-//  - PermittedEmailAddresses
-//  - PermittedIPRanges
-//  - PermittedURIDomains
-//  - PolicyIdentifiers
-//  - SerialNumber
-//  - SignatureAlgorithm
-//  - Subject
-//  - SubjectKeyId
-//  - URIs
-//  - UnknownExtKeyUsage
-//
-// The certificate is signed by parent. If parent is equal to template then the
-// certificate is self-signed. The parameter pub is the public key of the
-// certificate to be generated and priv is the private key of the signer.
-//
-// The returned slice is the certificate in DER encoding.
-//
-// The currently supported key types are *rsa.PublicKey, *ecdsa.PublicKey and
-// ed25519.PublicKey. pub must be a supported key type, and priv must be a
-// crypto.Signer with a supported public key.
-//
-// The AuthorityKeyId will be taken from the SubjectKeyId of parent, if any,
-// unless the resulting certificate is self-signed. Otherwise the value from
-// template will be used.
-//
-// If SubjectKeyId from template is empty and the template is a CA, SubjectKeyId
-// will be generated from the hash of the public key.
-func CreateCertificate(rand io.Reader, template, parent *Certificate, pub, priv any) ([]byte, error) {
-	key, ok := priv.(crypto.Signer)
-	if !ok {
-		return nil, errors.New("x509: certificate private key does not implement crypto.Signer")
-	}
-
-	if template.SerialNumber == nil {
-		return nil, errors.New("x509: no SerialNumber given")
-	}
-
-	if template.BasicConstraintsValid && !template.IsCA && template.MaxPathLen != -1 && (template.MaxPathLen != 0 || template.MaxPathLenZero) {
-		return nil, errors.New("x509: only CAs are allowed to specify MaxPathLen")
-	}
-
-	hashFunc, signatureAlgorithm, err := signingParamsForPublicKey(key.Public(), template.SignatureAlgorithm)
-	if err != nil {
-		return nil, err
-	}
-
-	publicKeyBytes, publicKeyAlgorithm, err := marshalPublicKey(pub)
-	if err != nil {
-		return nil, err
-	}
-
-	asn1Issuer, err := subjectBytes(parent)
-	if err != nil {
-		return nil, err
-	}
-
-	asn1Subject, err := subjectBytes(template)
-	if err != nil {
-		return nil, err
-	}
-
-	authorityKeyId := template.AuthorityKeyId
-	if !bytes.Equal(asn1Issuer, asn1Subject) && len(parent.SubjectKeyId) > 0 {
-		authorityKeyId = parent.SubjectKeyId
-	}
-
-	subjectKeyId := template.SubjectKeyId
-	if len(subjectKeyId) == 0 && template.IsCA {
-		// SubjectKeyId generated using method 1 in RFC 5280, Section 4.2.1.2:
-		//   (1) The keyIdentifier is composed of the 160-bit SHA-1 hash of the
-		//   value of the BIT STRING subjectPublicKey (excluding the tag,
-		//   length, and number of unused bits).
-		h := sha1.Sum(publicKeyBytes)
-		subjectKeyId = h[:]
-	}
-
-	// Check that the signer's public key matches the private key, if available.
-	type privateKey interface {
-		Equal(crypto.PublicKey) bool
-	}
-	if privPub, ok := key.Public().(privateKey); !ok {
-		return nil, errors.New("x509: internal error: supported public key does not implement Equal")
-	} else if parent.PublicKey != nil && !privPub.Equal(parent.PublicKey) {
-		return nil, errors.New("x509: provided PrivateKey doesn't match parent's PublicKey")
-	}
-
-	extensions, err := buildCertExtensions(template, bytes.Equal(asn1Subject, emptyASN1Subject), authorityKeyId, subjectKeyId)
-	if err != nil {
-		return nil, err
-	}
-
-	encodedPublicKey := asn1.BitString{BitLength: len(publicKeyBytes) * 8, Bytes: publicKeyBytes}
-	c := tbsCertificate{
-		Version:            2,
-		SerialNumber:       template.SerialNumber,
-		SignatureAlgorithm: signatureAlgorithm,
-		Issuer:             asn1.RawValue{FullBytes: asn1Issuer},
-		Validity:           validity{template.NotBefore.UTC(), template.NotAfter.UTC()},
-		Subject:            asn1.RawValue{FullBytes: asn1Subject},
-		PublicKey:          publicKeyInfo{nil, publicKeyAlgorithm, encodedPublicKey},
-		Extensions:         extensions,
-	}
-
-	tbsCertContents, err := asn1.Marshal(c)
-	if err != nil {
-		return nil, err
-	}
-	c.Raw = tbsCertContents
-
-	signed := tbsCertContents
-	if hashFunc != 0 {
-		h := hashFunc.New()
-		h.Write(signed)
-		signed = h.Sum(nil)
-	}
-
-	var signerOpts crypto.SignerOpts = hashFunc
-	if template.SignatureAlgorithm != 0 && template.SignatureAlgorithm.isRSAPSS() {
-		signerOpts = &rsa.PSSOptions{
-			SaltLength: rsa.PSSSaltLengthEqualsHash,
-			Hash:       hashFunc,
-		}
-	}
-
-	var signature []byte
-	signature, err = key.Sign(rand, signed, signerOpts)
-	if err != nil {
-		return nil, err
-	}
-
-	signedCert, err := asn1.Marshal(certificate{
-		nil,
-		c,
-		signatureAlgorithm,
-		asn1.BitString{Bytes: signature, BitLength: len(signature) * 8},
-	})
-	if err != nil {
-		return nil, err
-	}
-
-	// Check the signature to ensure the crypto.Signer behaved correctly.
-	sigAlg := getSignatureAlgorithmFromAI(signatureAlgorithm)
-	switch sigAlg {
-	case MD5WithRSA:
-		// We skip the check if the signature algorithm is only supported for
-		// signing, not verification.
-	default:
-		if err := checkSignature(sigAlg, c.Raw, signature, key.Public(), true); err != nil {
-			return nil, fmt.Errorf("x509: signature over certificate returned by signer is invalid: %w", err)
-		}
-	}
-
-	return signedCert, nil
-}
-
-// pemCRLPrefix is the magic string that indicates that we have a PEM encoded
-// CRL.
-var pemCRLPrefix = []byte("-----BEGIN X509 CRL")
-
-// pemType is the type of a PEM encoded CRL.
-var pemType = "X509 CRL"
-
-// ParseCRL parses a CRL from the given bytes. It's often the case that PEM
-// encoded CRLs will appear where they should be DER encoded, so this function
-// will transparently handle PEM encoding as long as there isn't any leading
-// garbage.
-func ParseCRL(crlBytes []byte) (*pkix.CertificateList, error) {
-	if bytes.HasPrefix(crlBytes, pemCRLPrefix) {
-		block, _ := pem.Decode(crlBytes)
-		if block != nil && block.Type == pemType {
-			crlBytes = block.Bytes
-		}
-	}
-	return ParseDERCRL(crlBytes)
-}
-
-// ParseDERCRL parses a DER encoded CRL from the given bytes.
-func ParseDERCRL(derBytes []byte) (*pkix.CertificateList, error) {
-	certList := new(pkix.CertificateList)
-	if rest, err := asn1.Unmarshal(derBytes, certList); err != nil {
-		return nil, err
-	} else if len(rest) != 0 {
-		return nil, errors.New("x509: trailing data after CRL")
-	}
-	return certList, nil
-}
-
-// CreateCRL returns a DER encoded CRL, signed by this Certificate, that
-// contains the given list of revoked certificates.
-//
-// Note: this method does not generate an RFC 5280 conformant X.509 v2 CRL.
-// To generate a standards compliant CRL, use CreateRevocationList instead.
-func (c *Certificate) CreateCRL(rand io.Reader, priv any, revokedCerts []pkix.RevokedCertificate, now, expiry time.Time) (crlBytes []byte, err error) {
-	key, ok := priv.(crypto.Signer)
-	if !ok {
-		return nil, errors.New("x509: certificate private key does not implement crypto.Signer")
-	}
-
-	hashFunc, signatureAlgorithm, err := signingParamsForPublicKey(key.Public(), 0)
-	if err != nil {
-		return nil, err
-	}
-
-	// Force revocation times to UTC per RFC 5280.
-	revokedCertsUTC := make([]pkix.RevokedCertificate, len(revokedCerts))
-	for i, rc := range revokedCerts {
-		rc.RevocationTime = rc.RevocationTime.UTC()
-		revokedCertsUTC[i] = rc
-	}
-
-	tbsCertList := pkix.TBSCertificateList{
-		Version:             1,
-		Signature:           signatureAlgorithm,
-		Issuer:              c.Subject.ToRDNSequence(),
-		ThisUpdate:          now.UTC(),
-		NextUpdate:          expiry.UTC(),
-		RevokedCertificates: revokedCertsUTC,
-	}
-
-	// Authority Key Id
-	if len(c.SubjectKeyId) > 0 {
-		var aki pkix.Extension
-		aki.Id = oidExtensionAuthorityKeyId
-		aki.Value, err = asn1.Marshal(authKeyId{Id: c.SubjectKeyId})
-		if err != nil {
-			return
-		}
-		tbsCertList.Extensions = append(tbsCertList.Extensions, aki)
-	}
-
-	tbsCertListContents, err := asn1.Marshal(tbsCertList)
-	if err != nil {
-		return
-	}
-
-	signed := tbsCertListContents
-	if hashFunc != 0 {
-		h := hashFunc.New()
-		h.Write(signed)
-		signed = h.Sum(nil)
-	}
-
-	var signature []byte
-	signature, err = key.Sign(rand, signed, hashFunc)
-	if err != nil {
-		return
-	}
-
-	return asn1.Marshal(pkix.CertificateList{
-		TBSCertList:        tbsCertList,
-		SignatureAlgorithm: signatureAlgorithm,
-		SignatureValue:     asn1.BitString{Bytes: signature, BitLength: len(signature) * 8},
-	})
-}
-
-// CertificateRequest represents a PKCS #10, certificate signature request.
-type CertificateRequest struct {
-	Raw                      []byte // Complete ASN.1 DER content (CSR, signature algorithm and signature).
-	RawTBSCertificateRequest []byte // Certificate request info part of raw ASN.1 DER content.
-	RawSubjectPublicKeyInfo  []byte // DER encoded SubjectPublicKeyInfo.
-	RawSubject               []byte // DER encoded Subject.
-
-	Version            int
-	Signature          []byte
-	SignatureAlgorithm SignatureAlgorithm
-
-	PublicKeyAlgorithm PublicKeyAlgorithm
-	PublicKey          any
-
-	Subject pkix.Name
-
-	// Attributes contains the CSR attributes that can parse as
-	// pkix.AttributeTypeAndValueSET.
-	//
-	// Deprecated: Use Extensions and ExtraExtensions instead for parsing and
-	// generating the requestedExtensions attribute.
-	Attributes []pkix.AttributeTypeAndValueSET
-
-	// Extensions contains all requested extensions, in raw form. When parsing
-	// CSRs, this can be used to extract extensions that are not parsed by this
-	// package.
-	Extensions []pkix.Extension
-
-	// ExtraExtensions contains extensions to be copied, raw, into any CSR
-	// marshaled by CreateCertificateRequest. Values override any extensions
-	// that would otherwise be produced based on the other fields but are
-	// overridden by any extensions specified in Attributes.
-	//
-	// The ExtraExtensions field is not populated by ParseCertificateRequest,
-	// see Extensions instead.
-	ExtraExtensions []pkix.Extension
-
-	// Subject Alternate Name values.
-	DNSNames       []string
-	EmailAddresses []string
-	IPAddresses    []net.IP
-	URIs           []*url.URL
-}
-
-// These structures reflect the ASN.1 structure of X.509 certificate
-// signature requests (see RFC 2986):
-
-type tbsCertificateRequest struct {
-	Raw           asn1.RawContent
-	Version       int
-	Subject       asn1.RawValue
-	PublicKey     publicKeyInfo
-	RawAttributes []asn1.RawValue `asn1:"tag:0"`
-}
-
-type certificateRequest struct {
-	Raw                asn1.RawContent
-	TBSCSR             tbsCertificateRequest
-	SignatureAlgorithm pkix.AlgorithmIdentifier
-	SignatureValue     asn1.BitString
-}
-
-// oidExtensionRequest is a PKCS #9 OBJECT IDENTIFIER that indicates requested
-// extensions in a CSR.
-var oidExtensionRequest = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 9, 14}
-
-// newRawAttributes converts AttributeTypeAndValueSETs from a template
-// CertificateRequest's Attributes into tbsCertificateRequest RawAttributes.
-func newRawAttributes(attributes []pkix.AttributeTypeAndValueSET) ([]asn1.RawValue, error) {
-	var rawAttributes []asn1.RawValue
-	b, err := asn1.Marshal(attributes)
-	if err != nil {
-		return nil, err
-	}
-	rest, err := asn1.Unmarshal(b, &rawAttributes)
-	if err != nil {
-		return nil, err
-	}
-	if len(rest) != 0 {
-		return nil, errors.New("x509: failed to unmarshal raw CSR Attributes")
-	}
-	return rawAttributes, nil
-}
-
-// parseRawAttributes Unmarshals RawAttributes into AttributeTypeAndValueSETs.
-func parseRawAttributes(rawAttributes []asn1.RawValue) []pkix.AttributeTypeAndValueSET {
-	var attributes []pkix.AttributeTypeAndValueSET
-	for _, rawAttr := range rawAttributes {
-		var attr pkix.AttributeTypeAndValueSET
-		rest, err := asn1.Unmarshal(rawAttr.FullBytes, &attr)
-		// Ignore attributes that don't parse into pkix.AttributeTypeAndValueSET
-		// (i.e.: challengePassword or unstructuredName).
-		if err == nil && len(rest) == 0 {
-			attributes = append(attributes, attr)
-		}
-	}
-	return attributes
-}
-
-// parseCSRExtensions parses the attributes from a CSR and extracts any
-// requested extensions.
-func parseCSRExtensions(rawAttributes []asn1.RawValue) ([]pkix.Extension, error) {
-	// pkcs10Attribute reflects the Attribute structure from RFC 2986, Section 4.1.
-	type pkcs10Attribute struct {
-		Id     asn1.ObjectIdentifier
-		Values []asn1.RawValue `asn1:"set"`
-	}
-
-	var ret []pkix.Extension
-	for _, rawAttr := range rawAttributes {
-		var attr pkcs10Attribute
-		if rest, err := asn1.Unmarshal(rawAttr.FullBytes, &attr); err != nil || len(rest) != 0 || len(attr.Values) == 0 {
-			// Ignore attributes that don't parse.
-			continue
-		}
-
-		if !attr.Id.Equal(oidExtensionRequest) {
-			continue
-		}
-
-		var extensions []pkix.Extension
-		if _, err := asn1.Unmarshal(attr.Values[0].FullBytes, &extensions); err != nil {
-			return nil, err
-		}
-		ret = append(ret, extensions...)
-	}
-
-	return ret, nil
-}
-
-// CreateCertificateRequest creates a new certificate request based on a
-// template. The following members of template are used:
-//
-//  - SignatureAlgorithm
-//  - Subject
-//  - DNSNames
-//  - EmailAddresses
-//  - IPAddresses
-//  - URIs
-//  - ExtraExtensions
-//  - Attributes (deprecated)
-//
-// priv is the private key to sign the CSR with, and the corresponding public
-// key will be included in the CSR. It must implement crypto.Signer and its
-// Public() method must return a *rsa.PublicKey or a *ecdsa.PublicKey or a
-// ed25519.PublicKey. (A *rsa.PrivateKey, *ecdsa.PrivateKey or
-// ed25519.PrivateKey satisfies this.)
-//
-// The returned slice is the certificate request in DER encoding.
-func CreateCertificateRequest(rand io.Reader, template *CertificateRequest, priv any) (csr []byte, err error) {
-	key, ok := priv.(crypto.Signer)
-	if !ok {
-		return nil, errors.New("x509: certificate private key does not implement crypto.Signer")
-	}
-
-	var hashFunc crypto.Hash
-	var sigAlgo pkix.AlgorithmIdentifier
-	hashFunc, sigAlgo, err = signingParamsForPublicKey(key.Public(), template.SignatureAlgorithm)
-	if err != nil {
-		return nil, err
-	}
-
-	var publicKeyBytes []byte
-	var publicKeyAlgorithm pkix.AlgorithmIdentifier
-	publicKeyBytes, publicKeyAlgorithm, err = marshalPublicKey(key.Public())
-	if err != nil {
-		return nil, err
-	}
-
-	extensions, err := buildCSRExtensions(template)
-	if err != nil {
-		return nil, err
-	}
-
-	// Make a copy of template.Attributes because we may alter it below.
-	attributes := make([]pkix.AttributeTypeAndValueSET, 0, len(template.Attributes))
-	for _, attr := range template.Attributes {
-		values := make([][]pkix.AttributeTypeAndValue, len(attr.Value))
-		copy(values, attr.Value)
-		attributes = append(attributes, pkix.AttributeTypeAndValueSET{
-			Type:  attr.Type,
-			Value: values,
-		})
-	}
-
-	extensionsAppended := false
-	if len(extensions) > 0 {
-		// Append the extensions to an existing attribute if possible.
-		for _, atvSet := range attributes {
-			if !atvSet.Type.Equal(oidExtensionRequest) || len(atvSet.Value) == 0 {
-				continue
-			}
-
-			// specifiedExtensions contains all the extensions that we
-			// found specified via template.Attributes.
-			specifiedExtensions := make(map[string]bool)
-
-			for _, atvs := range atvSet.Value {
-				for _, atv := range atvs {
-					specifiedExtensions[atv.Type.String()] = true
-				}
-			}
-
-			newValue := make([]pkix.AttributeTypeAndValue, 0, len(atvSet.Value[0])+len(extensions))
-			newValue = append(newValue, atvSet.Value[0]...)
-
-			for _, e := range extensions {
-				if specifiedExtensions[e.Id.String()] {
-					// Attributes already contained a value for
-					// this extension and it takes priority.
-					continue
-				}
-
-				newValue = append(newValue, pkix.AttributeTypeAndValue{
-					// There is no place for the critical
-					// flag in an AttributeTypeAndValue.
-					Type:  e.Id,
-					Value: e.Value,
-				})
-			}
-
-			atvSet.Value[0] = newValue
-			extensionsAppended = true
-			break
-		}
-	}
-
-	rawAttributes, err := newRawAttributes(attributes)
-	if err != nil {
-		return
-	}
-
-	// If not included in attributes, add a new attribute for the
-	// extensions.
-	if len(extensions) > 0 && !extensionsAppended {
-		attr := struct {
-			Type  asn1.ObjectIdentifier
-			Value [][]pkix.Extension `asn1:"set"`
-		}{
-			Type:  oidExtensionRequest,
-			Value: [][]pkix.Extension{extensions},
-		}
-
-		b, err := asn1.Marshal(attr)
-		if err != nil {
-			return nil, errors.New("x509: failed to serialise extensions attribute: " + err.Error())
-		}
-
-		var rawValue asn1.RawValue
-		if _, err := asn1.Unmarshal(b, &rawValue); err != nil {
-			return nil, err
-		}
-
-		rawAttributes = append(rawAttributes, rawValue)
-	}
-
-	asn1Subject := template.RawSubject
-	if len(asn1Subject) == 0 {
-		asn1Subject, err = asn1.Marshal(template.Subject.ToRDNSequence())
-		if err != nil {
-			return nil, err
-		}
-	}
-
-	tbsCSR := tbsCertificateRequest{
-		Version: 0, // PKCS #10, RFC 2986
-		Subject: asn1.RawValue{FullBytes: asn1Subject},
-		PublicKey: publicKeyInfo{
-			Algorithm: publicKeyAlgorithm,
-			PublicKey: asn1.BitString{
-				Bytes:     publicKeyBytes,
-				BitLength: len(publicKeyBytes) * 8,
-			},
-		},
-		RawAttributes: rawAttributes,
-	}
-
-	tbsCSRContents, err := asn1.Marshal(tbsCSR)
-	if err != nil {
-		return
-	}
-	tbsCSR.Raw = tbsCSRContents
-
-	signed := tbsCSRContents
-	if hashFunc != 0 {
-		h := hashFunc.New()
-		h.Write(signed)
-		signed = h.Sum(nil)
-	}
-
-	var signature []byte
-	signature, err = key.Sign(rand, signed, hashFunc)
-	if err != nil {
-		return
-	}
-
-	return asn1.Marshal(certificateRequest{
-		TBSCSR:             tbsCSR,
-		SignatureAlgorithm: sigAlgo,
-		SignatureValue: asn1.BitString{
-			Bytes:     signature,
-			BitLength: len(signature) * 8,
-		},
-	})
-}
-
-// ParseCertificateRequest parses a single certificate request from the
-// given ASN.1 DER data.
-func ParseCertificateRequest(asn1Data []byte) (*CertificateRequest, error) {
-	var csr certificateRequest
-
-	rest, err := asn1.Unmarshal(asn1Data, &csr)
-	if err != nil {
-		return nil, err
-	} else if len(rest) != 0 {
-		return nil, asn1.SyntaxError{Msg: "trailing data"}
-	}
-
-	return parseCertificateRequest(&csr)
-}
-
-func parseCertificateRequest(in *certificateRequest) (*CertificateRequest, error) {
-	out := &CertificateRequest{
-		Raw:                      in.Raw,
-		RawTBSCertificateRequest: in.TBSCSR.Raw,
-		RawSubjectPublicKeyInfo:  in.TBSCSR.PublicKey.Raw,
-		RawSubject:               in.TBSCSR.Subject.FullBytes,
-
-		Signature:          in.SignatureValue.RightAlign(),
-		SignatureAlgorithm: getSignatureAlgorithmFromAI(in.SignatureAlgorithm),
-
-		PublicKeyAlgorithm: getPublicKeyAlgorithmFromOID(in.TBSCSR.PublicKey.Algorithm.Algorithm),
-
-		Version:    in.TBSCSR.Version,
-		Attributes: parseRawAttributes(in.TBSCSR.RawAttributes),
-	}
-
-	var err error
-	out.PublicKey, err = parsePublicKey(out.PublicKeyAlgorithm, &in.TBSCSR.PublicKey)
-	if err != nil {
-		return nil, err
-	}
-
-	var subject pkix.RDNSequence
-	if rest, err := asn1.Unmarshal(in.TBSCSR.Subject.FullBytes, &subject); err != nil {
-		return nil, err
-	} else if len(rest) != 0 {
-		return nil, errors.New("x509: trailing data after X.509 Subject")
-	}
-
-	out.Subject.FillFromRDNSequence(&subject)
-
-	if out.Extensions, err = parseCSRExtensions(in.TBSCSR.RawAttributes); err != nil {
-		return nil, err
-	}
-
-	for _, extension := range out.Extensions {
-		switch {
-		case extension.Id.Equal(oidExtensionSubjectAltName):
-			out.DNSNames, out.EmailAddresses, out.IPAddresses, out.URIs, err = parseSANExtension(extension.Value)
-			if err != nil {
-				return nil, err
-			}
-		}
-	}
-
-	return out, nil
-}
-
-// CheckSignature reports whether the signature on c is valid.
-func (c *CertificateRequest) CheckSignature() error {
-	return checkSignature(c.SignatureAlgorithm, c.RawTBSCertificateRequest, c.Signature, c.PublicKey, true)
-}
-
-// RevocationList contains the fields used to create an X.509 v2 Certificate
-// Revocation list with CreateRevocationList.
-type RevocationList struct {
-	// SignatureAlgorithm is used to determine the signature algorithm to be
-	// used when signing the CRL. If 0 the default algorithm for the signing
-	// key will be used.
-	SignatureAlgorithm SignatureAlgorithm
-
-	// RevokedCertificates is used to populate the revokedCertificates
-	// sequence in the CRL, it may be empty. RevokedCertificates may be nil,
-	// in which case an empty CRL will be created.
-	RevokedCertificates []pkix.RevokedCertificate
-
-	// Number is used to populate the X.509 v2 cRLNumber extension in the CRL,
-	// which should be a monotonically increasing sequence number for a given
-	// CRL scope and CRL issuer.
-	Number *big.Int
-	// ThisUpdate is used to populate the thisUpdate field in the CRL, which
-	// indicates the issuance date of the CRL.
-	ThisUpdate time.Time
-	// NextUpdate is used to populate the nextUpdate field in the CRL, which
-	// indicates the date by which the next CRL will be issued. NextUpdate
-	// must be greater than ThisUpdate.
-	NextUpdate time.Time
-	// ExtraExtensions contains any additional extensions to add directly to
-	// the CRL.
-	ExtraExtensions []pkix.Extension
-}
-
-// CreateRevocationList creates a new X.509 v2 Certificate Revocation List,
-// according to RFC 5280, based on template.
-//
-// The CRL is signed by priv which should be the private key associated with
-// the public key in the issuer certificate.
-//
-// The issuer may not be nil, and the crlSign bit must be set in KeyUsage in
-// order to use it as a CRL issuer.
-//
-// The issuer distinguished name CRL field and authority key identifier
-// extension are populated using the issuer certificate. issuer must have
-// SubjectKeyId set.
-func CreateRevocationList(rand io.Reader, template *RevocationList, issuer *Certificate, priv crypto.Signer) ([]byte, error) {
-	if template == nil {
-		return nil, errors.New("x509: template can not be nil")
-	}
-	if issuer == nil {
-		return nil, errors.New("x509: issuer can not be nil")
-	}
-	if (issuer.KeyUsage & KeyUsageCRLSign) == 0 {
-		return nil, errors.New("x509: issuer must have the crlSign key usage bit set")
-	}
-	if len(issuer.SubjectKeyId) == 0 {
-		return nil, errors.New("x509: issuer certificate doesn't contain a subject key identifier")
-	}
-	if template.NextUpdate.Before(template.ThisUpdate) {
-		return nil, errors.New("x509: template.ThisUpdate is after template.NextUpdate")
-	}
-	if template.Number == nil {
-		return nil, errors.New("x509: template contains nil Number field")
-	}
-
-	hashFunc, signatureAlgorithm, err := signingParamsForPublicKey(priv.Public(), template.SignatureAlgorithm)
-	if err != nil {
-		return nil, err
-	}
-
-	// Force revocation times to UTC per RFC 5280.
-	revokedCertsUTC := make([]pkix.RevokedCertificate, len(template.RevokedCertificates))
-	for i, rc := range template.RevokedCertificates {
-		rc.RevocationTime = rc.RevocationTime.UTC()
-		revokedCertsUTC[i] = rc
-	}
-
-	aki, err := asn1.Marshal(authKeyId{Id: issuer.SubjectKeyId})
-	if err != nil {
-		return nil, err
-	}
-	crlNum, err := asn1.Marshal(template.Number)
-	if err != nil {
-		return nil, err
-	}
-
-	tbsCertList := pkix.TBSCertificateList{
-		Version:    1, // v2
-		Signature:  signatureAlgorithm,
-		Issuer:     issuer.Subject.ToRDNSequence(),
-		ThisUpdate: template.ThisUpdate.UTC(),
-		NextUpdate: template.NextUpdate.UTC(),
-		Extensions: []pkix.Extension{
-			{
-				Id:    oidExtensionAuthorityKeyId,
-				Value: aki,
-			},
-			{
-				Id:    oidExtensionCRLNumber,
-				Value: crlNum,
-			},
-		},
-	}
-	if len(revokedCertsUTC) > 0 {
-		tbsCertList.RevokedCertificates = revokedCertsUTC
-	}
-
-	if len(template.ExtraExtensions) > 0 {
-		tbsCertList.Extensions = append(tbsCertList.Extensions, template.ExtraExtensions...)
-	}
-
-	tbsCertListContents, err := asn1.Marshal(tbsCertList)
-	if err != nil {
-		return nil, err
-	}
-
-	input := tbsCertListContents
-	if hashFunc != 0 {
-		h := hashFunc.New()
-		h.Write(tbsCertListContents)
-		input = h.Sum(nil)
-	}
-	var signerOpts crypto.SignerOpts = hashFunc
-	if template.SignatureAlgorithm.isRSAPSS() {
-		signerOpts = &rsa.PSSOptions{
-			SaltLength: rsa.PSSSaltLengthEqualsHash,
-			Hash:       hashFunc,
-		}
-	}
-
-	signature, err := priv.Sign(rand, input, signerOpts)
-	if err != nil {
-		return nil, err
-	}
-
-	return asn1.Marshal(pkix.CertificateList{
-		TBSCertList:        tbsCertList,
-		SignatureAlgorithm: signatureAlgorithm,
-		SignatureValue:     asn1.BitString{Bytes: signature, BitLength: len(signature) * 8},
-	})
-}
diff --git a/contrib/go/_std_1.18/src/embed/embed.go b/contrib/go/_std_1.18/src/embed/embed.go
deleted file mode 100644
index 9737ccdf6b..0000000000
--- a/contrib/go/_std_1.18/src/embed/embed.go
+++ /dev/null
@@ -1,432 +0,0 @@
-// Copyright 2020 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package embed provides access to files embedded in the running Go program.
-//
-// Go source files that import "embed" can use the //go:embed directive
-// to initialize a variable of type string, []byte, or FS with the contents of
-// files read from the package directory or subdirectories at compile time.
-//
-// For example, here are three ways to embed a file named hello.txt
-// and then print its contents at run time.
-//
-// Embedding one file into a string:
-//
-//	import _ "embed"
-//
-//	//go:embed hello.txt
-//	var s string
-//	print(s)
-//
-// Embedding one file into a slice of bytes:
-//
-//	import _ "embed"
-//
-//	//go:embed hello.txt
-//	var b []byte
-//	print(string(b))
-//
-// Embedded one or more files into a file system:
-//
-//	import "embed"
-//
-//	//go:embed hello.txt
-//	var f embed.FS
-//	data, _ := f.ReadFile("hello.txt")
-//	print(string(data))
-//
-// Directives
-//
-// A //go:embed directive above a variable declaration specifies which files to embed,
-// using one or more path.Match patterns.
-//
-// The directive must immediately precede a line containing the declaration of a single variable.
-// Only blank lines and ‘//’ line comments are permitted between the directive and the declaration.
-//
-// The type of the variable must be a string type, or a slice of a byte type,
-// or FS (or an alias of FS).
-//
-// For example:
-//
-//	package server
-//
-//	import "embed"
-//
-//	// content holds our static web server content.
-//	//go:embed image/* template/*
-//	//go:embed html/index.html
-//	var content embed.FS
-//
-// The Go build system will recognize the directives and arrange for the declared variable
-// (in the example above, content) to be populated with the matching files from the file system.
-//
-// The //go:embed directive accepts multiple space-separated patterns for
-// brevity, but it can also be repeated, to avoid very long lines when there are
-// many patterns. The patterns are interpreted relative to the package directory
-// containing the source file. The path separator is a forward slash, even on
-// Windows systems. Patterns may not contain ‘.’ or ‘..’ or empty path elements,
-// nor may they begin or end with a slash. To match everything in the current
-// directory, use ‘*’ instead of ‘.’. To allow for naming files with spaces in
-// their names, patterns can be written as Go double-quoted or back-quoted
-// string literals.
-//
-// If a pattern names a directory, all files in the subtree rooted at that directory are
-// embedded (recursively), except that files with names beginning with ‘.’ or ‘_’
-// are excluded. So the variable in the above example is almost equivalent to:
-//
-//	// content is our static web server content.
-//	//go:embed image template html/index.html
-//	var content embed.FS
-//
-// The difference is that ‘image/*’ embeds ‘image/.tempfile’ while ‘image’ does not.
-// Neither embeds ‘image/dir/.tempfile’.
-//
-// If a pattern begins with the prefix ‘all:’, then the rule for walking directories is changed
-// to include those files beginning with ‘.’ or ‘_’. For example, ‘all:image’ embeds
-// both ‘image/.tempfile’ and ‘image/dir/.tempfile’.
-//
-// The //go:embed directive can be used with both exported and unexported variables,
-// depending on whether the package wants to make the data available to other packages.
-// It can only be used with variables at package scope, not with local variables.
-//
-// Patterns must not match files outside the package's module, such as ‘.git/*’ or symbolic links.
-// Matches for empty directories are ignored. After that, each pattern in a //go:embed line
-// must match at least one file or non-empty directory.
-//
-// If any patterns are invalid or have invalid matches, the build will fail.
-//
-// Strings and Bytes
-//
-// The //go:embed line for a variable of type string or []byte can have only a single pattern,
-// and that pattern can match only a single file. The string or []byte is initialized with
-// the contents of that file.
-//
-// The //go:embed directive requires importing "embed", even when using a string or []byte.
-// In source files that don't refer to embed.FS, use a blank import (import _ "embed").
-//
-// File Systems
-//
-// For embedding a single file, a variable of type string or []byte is often best.
-// The FS type enables embedding a tree of files, such as a directory of static
-// web server content, as in the example above.
-//
-// FS implements the io/fs package's FS interface, so it can be used with any package that
-// understands file systems, including net/http, text/template, and html/template.
-//
-// For example, given the content variable in the example above, we can write:
-//
-//	http.Handle("/static/", http.StripPrefix("/static/", http.FileServer(http.FS(content))))
-//
-//	template.ParseFS(content, "*.tmpl")
-//
-// Tools
-//
-// To support tools that analyze Go packages, the patterns found in //go:embed lines
-// are available in “go list” output. See the EmbedPatterns, TestEmbedPatterns,
-// and XTestEmbedPatterns fields in the “go help list” output.
-//
-package embed
-
-import (
-	"errors"
-	"io"
-	"io/fs"
-	"time"
-)
-
-// An FS is a read-only collection of files, usually initialized with a //go:embed directive.
-// When declared without a //go:embed directive, an FS is an empty file system.
-//
-// An FS is a read-only value, so it is safe to use from multiple goroutines
-// simultaneously and also safe to assign values of type FS to each other.
-//
-// FS implements fs.FS, so it can be used with any package that understands
-// file system interfaces, including net/http, text/template, and html/template.
-//
-// See the package documentation for more details about initializing an FS.
-type FS struct {
-	// The compiler knows the layout of this struct.
-	// See cmd/compile/internal/staticdata's WriteEmbed.
-	//
-	// The files list is sorted by name but not by simple string comparison.
-	// Instead, each file's name takes the form "dir/elem" or "dir/elem/".
-	// The optional trailing slash indicates that the file is itself a directory.
-	// The files list is sorted first by dir (if dir is missing, it is taken to be ".")
-	// and then by base, so this list of files:
-	//
-	//	p
-	//	q/
-	//	q/r
-	//	q/s/
-	//	q/s/t
-	//	q/s/u
-	//	q/v
-	//	w
-	//
-	// is actually sorted as:
-	//
-	//	p       # dir=.    elem=p
-	//	q/      # dir=.    elem=q
-	//	w/      # dir=.    elem=w
-	//	q/r     # dir=q    elem=r
-	//	q/s/    # dir=q    elem=s
-	//	q/v     # dir=q    elem=v
-	//	q/s/t   # dir=q/s  elem=t
-	//	q/s/u   # dir=q/s  elem=u
-	//
-	// This order brings directory contents together in contiguous sections
-	// of the list, allowing a directory read to use binary search to find
-	// the relevant sequence of entries.
-	files *[]file
-}
-
-// split splits the name into dir and elem as described in the
-// comment in the FS struct above. isDir reports whether the
-// final trailing slash was present, indicating that name is a directory.
-func split(name string) (dir, elem string, isDir bool) {
-	if name[len(name)-1] == '/' {
-		isDir = true
-		name = name[:len(name)-1]
-	}
-	i := len(name) - 1
-	for i >= 0 && name[i] != '/' {
-		i--
-	}
-	if i < 0 {
-		return ".", name, isDir
-	}
-	return name[:i], name[i+1:], isDir
-}
-
-// trimSlash trims a trailing slash from name, if present,
-// returning the possibly shortened name.
-func trimSlash(name string) string {
-	if len(name) > 0 && name[len(name)-1] == '/' {
-		return name[:len(name)-1]
-	}
-	return name
-}
-
-var (
-	_ fs.ReadDirFS  = FS{}
-	_ fs.ReadFileFS = FS{}
-)
-
-// A file is a single file in the FS.
-// It implements fs.FileInfo and fs.DirEntry.
-type file struct {
-	// The compiler knows the layout of this struct.
-	// See cmd/compile/internal/staticdata's WriteEmbed.
-	name string
-	data string
-	hash [16]byte // truncated SHA256 hash
-}
-
-var (
-	_ fs.FileInfo = (*file)(nil)
-	_ fs.DirEntry = (*file)(nil)
-)
-
-func (f *file) Name() string               { _, elem, _ := split(f.name); return elem }
-func (f *file) Size() int64                { return int64(len(f.data)) }
-func (f *file) ModTime() time.Time         { return time.Time{} }
-func (f *file) IsDir() bool                { _, _, isDir := split(f.name); return isDir }
-func (f *file) Sys() any                   { return nil }
-func (f *file) Type() fs.FileMode          { return f.Mode().Type() }
-func (f *file) Info() (fs.FileInfo, error) { return f, nil }
-
-func (f *file) Mode() fs.FileMode {
-	if f.IsDir() {
-		return fs.ModeDir | 0555
-	}
-	return 0444
-}
-
-// dotFile is a file for the root directory,
-// which is omitted from the files list in a FS.
-var dotFile = &file{name: "./"}
-
-// lookup returns the named file, or nil if it is not present.
-func (f FS) lookup(name string) *file {
-	if !fs.ValidPath(name) {
-		// The compiler should never emit a file with an invalid name,
-		// so this check is not strictly necessary (if name is invalid,
-		// we shouldn't find a match below), but it's a good backstop anyway.
-		return nil
-	}
-	if name == "." {
-		return dotFile
-	}
-	if f.files == nil {
-		return nil
-	}
-
-	// Binary search to find where name would be in the list,
-	// and then check if name is at that position.
-	dir, elem, _ := split(name)
-	files := *f.files
-	i := sortSearch(len(files), func(i int) bool {
-		idir, ielem, _ := split(files[i].name)
-		return idir > dir || idir == dir && ielem >= elem
-	})
-	if i < len(files) && trimSlash(files[i].name) == name {
-		return &files[i]
-	}
-	return nil
-}
-
-// readDir returns the list of files corresponding to the directory dir.
-func (f FS) readDir(dir string) []file {
-	if f.files == nil {
-		return nil
-	}
-	// Binary search to find where dir starts and ends in the list
-	// and then return that slice of the list.
-	files := *f.files
-	i := sortSearch(len(files), func(i int) bool {
-		idir, _, _ := split(files[i].name)
-		return idir >= dir
-	})
-	j := sortSearch(len(files), func(j int) bool {
-		jdir, _, _ := split(files[j].name)
-		return jdir > dir
-	})
-	return files[i:j]
-}
-
-// Open opens the named file for reading and returns it as an fs.File.
-//
-// The returned file implements io.Seeker when the file is not a directory.
-func (f FS) Open(name string) (fs.File, error) {
-	file := f.lookup(name)
-	if file == nil {
-		return nil, &fs.PathError{Op: "open", Path: name, Err: fs.ErrNotExist}
-	}
-	if file.IsDir() {
-		return &openDir{file, f.readDir(name), 0}, nil
-	}
-	return &openFile{file, 0}, nil
-}
-
-// ReadDir reads and returns the entire named directory.
-func (f FS) ReadDir(name string) ([]fs.DirEntry, error) {
-	file, err := f.Open(name)
-	if err != nil {
-		return nil, err
-	}
-	dir, ok := file.(*openDir)
-	if !ok {
-		return nil, &fs.PathError{Op: "read", Path: name, Err: errors.New("not a directory")}
-	}
-	list := make([]fs.DirEntry, len(dir.files))
-	for i := range list {
-		list[i] = &dir.files[i]
-	}
-	return list, nil
-}
-
-// ReadFile reads and returns the content of the named file.
-func (f FS) ReadFile(name string) ([]byte, error) {
-	file, err := f.Open(name)
-	if err != nil {
-		return nil, err
-	}
-	ofile, ok := file.(*openFile)
-	if !ok {
-		return nil, &fs.PathError{Op: "read", Path: name, Err: errors.New("is a directory")}
-	}
-	return []byte(ofile.f.data), nil
-}
-
-// An openFile is a regular file open for reading.
-type openFile struct {
-	f      *file // the file itself
-	offset int64 // current read offset
-}
-
-var (
-	_ io.Seeker = (*openFile)(nil)
-)
-
-func (f *openFile) Close() error               { return nil }
-func (f *openFile) Stat() (fs.FileInfo, error) { return f.f, nil }
-
-func (f *openFile) Read(b []byte) (int, error) {
-	if f.offset >= int64(len(f.f.data)) {
-		return 0, io.EOF
-	}
-	if f.offset < 0 {
-		return 0, &fs.PathError{Op: "read", Path: f.f.name, Err: fs.ErrInvalid}
-	}
-	n := copy(b, f.f.data[f.offset:])
-	f.offset += int64(n)
-	return n, nil
-}
-
-func (f *openFile) Seek(offset int64, whence int) (int64, error) {
-	switch whence {
-	case 0:
-		// offset += 0
-	case 1:
-		offset += f.offset
-	case 2:
-		offset += int64(len(f.f.data))
-	}
-	if offset < 0 || offset > int64(len(f.f.data)) {
-		return 0, &fs.PathError{Op: "seek", Path: f.f.name, Err: fs.ErrInvalid}
-	}
-	f.offset = offset
-	return offset, nil
-}
-
-// An openDir is a directory open for reading.
-type openDir struct {
-	f      *file  // the directory file itself
-	files  []file // the directory contents
-	offset int    // the read offset, an index into the files slice
-}
-
-func (d *openDir) Close() error               { return nil }
-func (d *openDir) Stat() (fs.FileInfo, error) { return d.f, nil }
-
-func (d *openDir) Read([]byte) (int, error) {
-	return 0, &fs.PathError{Op: "read", Path: d.f.name, Err: errors.New("is a directory")}
-}
-
-func (d *openDir) ReadDir(count int) ([]fs.DirEntry, error) {
-	n := len(d.files) - d.offset
-	if n == 0 {
-		if count <= 0 {
-			return nil, nil
-		}
-		return nil, io.EOF
-	}
-	if count > 0 && n > count {
-		n = count
-	}
-	list := make([]fs.DirEntry, n)
-	for i := range list {
-		list[i] = &d.files[d.offset+i]
-	}
-	d.offset += n
-	return list, nil
-}
-
-// sortSearch is like sort.Search, avoiding an import.
-func sortSearch(n int, f func(int) bool) int {
-	// Define f(-1) == false and f(n) == true.
-	// Invariant: f(i-1) == false, f(j) == true.
-	i, j := 0, n
-	for i < j {
-		h := int(uint(i+j) >> 1) // avoid overflow when computing h
-		// i ≤ h < j
-		if !f(h) {
-			i = h + 1 // preserves f(i-1) == false
-		} else {
-			j = h // preserves f(j) == true
-		}
-	}
-	// i == j, f(i-1) == false, and f(j) (= f(i)) == true  =>  answer is i.
-	return i
-}
diff --git a/contrib/go/_std_1.18/src/encoding/asn1/asn1.go b/contrib/go/_std_1.18/src/encoding/asn1/asn1.go
deleted file mode 100644
index cad1d7b08f..0000000000
--- a/contrib/go/_std_1.18/src/encoding/asn1/asn1.go
+++ /dev/null
@@ -1,1122 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package asn1 implements parsing of DER-encoded ASN.1 data structures,
-// as defined in ITU-T Rec X.690.
-//
-// See also ``A Layman's Guide to a Subset of ASN.1, BER, and DER,''
-// http://luca.ntop.org/Teaching/Appunti/asn1.html.
-package asn1
-
-// ASN.1 is a syntax for specifying abstract objects and BER, DER, PER, XER etc
-// are different encoding formats for those objects. Here, we'll be dealing
-// with DER, the Distinguished Encoding Rules. DER is used in X.509 because
-// it's fast to parse and, unlike BER, has a unique encoding for every object.
-// When calculating hashes over objects, it's important that the resulting
-// bytes be the same at both ends and DER removes this margin of error.
-//
-// ASN.1 is very complex and this package doesn't attempt to implement
-// everything by any means.
-
-import (
-	"errors"
-	"fmt"
-	"math"
-	"math/big"
-	"reflect"
-	"strconv"
-	"time"
-	"unicode/utf16"
-	"unicode/utf8"
-)
-
-// A StructuralError suggests that the ASN.1 data is valid, but the Go type
-// which is receiving it doesn't match.
-type StructuralError struct {
-	Msg string
-}
-
-func (e StructuralError) Error() string { return "asn1: structure error: " + e.Msg }
-
-// A SyntaxError suggests that the ASN.1 data is invalid.
-type SyntaxError struct {
-	Msg string
-}
-
-func (e SyntaxError) Error() string { return "asn1: syntax error: " + e.Msg }
-
-// We start by dealing with each of the primitive types in turn.
-
-// BOOLEAN
-
-func parseBool(bytes []byte) (ret bool, err error) {
-	if len(bytes) != 1 {
-		err = SyntaxError{"invalid boolean"}
-		return
-	}
-
-	// DER demands that "If the encoding represents the boolean value TRUE,
-	// its single contents octet shall have all eight bits set to one."
-	// Thus only 0 and 255 are valid encoded values.
-	switch bytes[0] {
-	case 0:
-		ret = false
-	case 0xff:
-		ret = true
-	default:
-		err = SyntaxError{"invalid boolean"}
-	}
-
-	return
-}
-
-// INTEGER
-
-// checkInteger returns nil if the given bytes are a valid DER-encoded
-// INTEGER and an error otherwise.
-func checkInteger(bytes []byte) error {
-	if len(bytes) == 0 {
-		return StructuralError{"empty integer"}
-	}
-	if len(bytes) == 1 {
-		return nil
-	}
-	if (bytes[0] == 0 && bytes[1]&0x80 == 0) || (bytes[0] == 0xff && bytes[1]&0x80 == 0x80) {
-		return StructuralError{"integer not minimally-encoded"}
-	}
-	return nil
-}
-
-// parseInt64 treats the given bytes as a big-endian, signed integer and
-// returns the result.
-func parseInt64(bytes []byte) (ret int64, err error) {
-	err = checkInteger(bytes)
-	if err != nil {
-		return
-	}
-	if len(bytes) > 8 {
-		// We'll overflow an int64 in this case.
-		err = StructuralError{"integer too large"}
-		return
-	}
-	for bytesRead := 0; bytesRead < len(bytes); bytesRead++ {
-		ret <<= 8
-		ret |= int64(bytes[bytesRead])
-	}
-
-	// Shift up and down in order to sign extend the result.
-	ret <<= 64 - uint8(len(bytes))*8
-	ret >>= 64 - uint8(len(bytes))*8
-	return
-}
-
-// parseInt treats the given bytes as a big-endian, signed integer and returns
-// the result.
-func parseInt32(bytes []byte) (int32, error) {
-	if err := checkInteger(bytes); err != nil {
-		return 0, err
-	}
-	ret64, err := parseInt64(bytes)
-	if err != nil {
-		return 0, err
-	}
-	if ret64 != int64(int32(ret64)) {
-		return 0, StructuralError{"integer too large"}
-	}
-	return int32(ret64), nil
-}
-
-var bigOne = big.NewInt(1)
-
-// parseBigInt treats the given bytes as a big-endian, signed integer and returns
-// the result.
-func parseBigInt(bytes []byte) (*big.Int, error) {
-	if err := checkInteger(bytes); err != nil {
-		return nil, err
-	}
-	ret := new(big.Int)
-	if len(bytes) > 0 && bytes[0]&0x80 == 0x80 {
-		// This is a negative number.
-		notBytes := make([]byte, len(bytes))
-		for i := range notBytes {
-			notBytes[i] = ^bytes[i]
-		}
-		ret.SetBytes(notBytes)
-		ret.Add(ret, bigOne)
-		ret.Neg(ret)
-		return ret, nil
-	}
-	ret.SetBytes(bytes)
-	return ret, nil
-}
-
-// BIT STRING
-
-// BitString is the structure to use when you want an ASN.1 BIT STRING type. A
-// bit string is padded up to the nearest byte in memory and the number of
-// valid bits is recorded. Padding bits will be zero.
-type BitString struct {
-	Bytes     []byte // bits packed into bytes.
-	BitLength int    // length in bits.
-}
-
-// At returns the bit at the given index. If the index is out of range it
-// returns false.
-func (b BitString) At(i int) int {
-	if i < 0 || i >= b.BitLength {
-		return 0
-	}
-	x := i / 8
-	y := 7 - uint(i%8)
-	return int(b.Bytes[x]>>y) & 1
-}
-
-// RightAlign returns a slice where the padding bits are at the beginning. The
-// slice may share memory with the BitString.
-func (b BitString) RightAlign() []byte {
-	shift := uint(8 - (b.BitLength % 8))
-	if shift == 8 || len(b.Bytes) == 0 {
-		return b.Bytes
-	}
-
-	a := make([]byte, len(b.Bytes))
-	a[0] = b.Bytes[0] >> shift
-	for i := 1; i < len(b.Bytes); i++ {
-		a[i] = b.Bytes[i-1] << (8 - shift)
-		a[i] |= b.Bytes[i] >> shift
-	}
-
-	return a
-}
-
-// parseBitString parses an ASN.1 bit string from the given byte slice and returns it.
-func parseBitString(bytes []byte) (ret BitString, err error) {
-	if len(bytes) == 0 {
-		err = SyntaxError{"zero length BIT STRING"}
-		return
-	}
-	paddingBits := int(bytes[0])
-	if paddingBits > 7 ||
-		len(bytes) == 1 && paddingBits > 0 ||
-		bytes[len(bytes)-1]&((1<<bytes[0])-1) != 0 {
-		err = SyntaxError{"invalid padding bits in BIT STRING"}
-		return
-	}
-	ret.BitLength = (len(bytes)-1)*8 - paddingBits
-	ret.Bytes = bytes[1:]
-	return
-}
-
-// NULL
-
-// NullRawValue is a RawValue with its Tag set to the ASN.1 NULL type tag (5).
-var NullRawValue = RawValue{Tag: TagNull}
-
-// NullBytes contains bytes representing the DER-encoded ASN.1 NULL type.
-var NullBytes = []byte{TagNull, 0}
-
-// OBJECT IDENTIFIER
-
-// An ObjectIdentifier represents an ASN.1 OBJECT IDENTIFIER.
-type ObjectIdentifier []int
-
-// Equal reports whether oi and other represent the same identifier.
-func (oi ObjectIdentifier) Equal(other ObjectIdentifier) bool {
-	if len(oi) != len(other) {
-		return false
-	}
-	for i := 0; i < len(oi); i++ {
-		if oi[i] != other[i] {
-			return false
-		}
-	}
-
-	return true
-}
-
-func (oi ObjectIdentifier) String() string {
-	var s string
-
-	for i, v := range oi {
-		if i > 0 {
-			s += "."
-		}
-		s += strconv.Itoa(v)
-	}
-
-	return s
-}
-
-// parseObjectIdentifier parses an OBJECT IDENTIFIER from the given bytes and
-// returns it. An object identifier is a sequence of variable length integers
-// that are assigned in a hierarchy.
-func parseObjectIdentifier(bytes []byte) (s ObjectIdentifier, err error) {
-	if len(bytes) == 0 {
-		err = SyntaxError{"zero length OBJECT IDENTIFIER"}
-		return
-	}
-
-	// In the worst case, we get two elements from the first byte (which is
-	// encoded differently) and then every varint is a single byte long.
-	s = make([]int, len(bytes)+1)
-
-	// The first varint is 40*value1 + value2:
-	// According to this packing, value1 can take the values 0, 1 and 2 only.
-	// When value1 = 0 or value1 = 1, then value2 is <= 39. When value1 = 2,
-	// then there are no restrictions on value2.
-	v, offset, err := parseBase128Int(bytes, 0)
-	if err != nil {
-		return
-	}
-	if v < 80 {
-		s[0] = v / 40
-		s[1] = v % 40
-	} else {
-		s[0] = 2
-		s[1] = v - 80
-	}
-
-	i := 2
-	for ; offset < len(bytes); i++ {
-		v, offset, err = parseBase128Int(bytes, offset)
-		if err != nil {
-			return
-		}
-		s[i] = v
-	}
-	s = s[0:i]
-	return
-}
-
-// ENUMERATED
-
-// An Enumerated is represented as a plain int.
-type Enumerated int
-
-// FLAG
-
-// A Flag accepts any data and is set to true if present.
-type Flag bool
-
-// parseBase128Int parses a base-128 encoded int from the given offset in the
-// given byte slice. It returns the value and the new offset.
-func parseBase128Int(bytes []byte, initOffset int) (ret, offset int, err error) {
-	offset = initOffset
-	var ret64 int64
-	for shifted := 0; offset < len(bytes); shifted++ {
-		// 5 * 7 bits per byte == 35 bits of data
-		// Thus the representation is either non-minimal or too large for an int32
-		if shifted == 5 {
-			err = StructuralError{"base 128 integer too large"}
-			return
-		}
-		ret64 <<= 7
-		b := bytes[offset]
-		// integers should be minimally encoded, so the leading octet should
-		// never be 0x80
-		if shifted == 0 && b == 0x80 {
-			err = SyntaxError{"integer is not minimally encoded"}
-			return
-		}
-		ret64 |= int64(b & 0x7f)
-		offset++
-		if b&0x80 == 0 {
-			ret = int(ret64)
-			// Ensure that the returned value fits in an int on all platforms
-			if ret64 > math.MaxInt32 {
-				err = StructuralError{"base 128 integer too large"}
-			}
-			return
-		}
-	}
-	err = SyntaxError{"truncated base 128 integer"}
-	return
-}
-
-// UTCTime
-
-func parseUTCTime(bytes []byte) (ret time.Time, err error) {
-	s := string(bytes)
-
-	formatStr := "0601021504Z0700"
-	ret, err = time.Parse(formatStr, s)
-	if err != nil {
-		formatStr = "060102150405Z0700"
-		ret, err = time.Parse(formatStr, s)
-	}
-	if err != nil {
-		return
-	}
-
-	if serialized := ret.Format(formatStr); serialized != s {
-		err = fmt.Errorf("asn1: time did not serialize back to the original value and may be invalid: given %q, but serialized as %q", s, serialized)
-		return
-	}
-
-	if ret.Year() >= 2050 {
-		// UTCTime only encodes times prior to 2050. See https://tools.ietf.org/html/rfc5280#section-4.1.2.5.1
-		ret = ret.AddDate(-100, 0, 0)
-	}
-
-	return
-}
-
-// parseGeneralizedTime parses the GeneralizedTime from the given byte slice
-// and returns the resulting time.
-func parseGeneralizedTime(bytes []byte) (ret time.Time, err error) {
-	const formatStr = "20060102150405Z0700"
-	s := string(bytes)
-
-	if ret, err = time.Parse(formatStr, s); err != nil {
-		return
-	}
-
-	if serialized := ret.Format(formatStr); serialized != s {
-		err = fmt.Errorf("asn1: time did not serialize back to the original value and may be invalid: given %q, but serialized as %q", s, serialized)
-	}
-
-	return
-}
-
-// NumericString
-
-// parseNumericString parses an ASN.1 NumericString from the given byte array
-// and returns it.
-func parseNumericString(bytes []byte) (ret string, err error) {
-	for _, b := range bytes {
-		if !isNumeric(b) {
-			return "", SyntaxError{"NumericString contains invalid character"}
-		}
-	}
-	return string(bytes), nil
-}
-
-// isNumeric reports whether the given b is in the ASN.1 NumericString set.
-func isNumeric(b byte) bool {
-	return '0' <= b && b <= '9' ||
-		b == ' '
-}
-
-// PrintableString
-
-// parsePrintableString parses an ASN.1 PrintableString from the given byte
-// array and returns it.
-func parsePrintableString(bytes []byte) (ret string, err error) {
-	for _, b := range bytes {
-		if !isPrintable(b, allowAsterisk, allowAmpersand) {
-			err = SyntaxError{"PrintableString contains invalid character"}
-			return
-		}
-	}
-	ret = string(bytes)
-	return
-}
-
-type asteriskFlag bool
-type ampersandFlag bool
-
-const (
-	allowAsterisk  asteriskFlag = true
-	rejectAsterisk asteriskFlag = false
-
-	allowAmpersand  ampersandFlag = true
-	rejectAmpersand ampersandFlag = false
-)
-
-// isPrintable reports whether the given b is in the ASN.1 PrintableString set.
-// If asterisk is allowAsterisk then '*' is also allowed, reflecting existing
-// practice. If ampersand is allowAmpersand then '&' is allowed as well.
-func isPrintable(b byte, asterisk asteriskFlag, ampersand ampersandFlag) bool {
-	return 'a' <= b && b <= 'z' ||
-		'A' <= b && b <= 'Z' ||
-		'0' <= b && b <= '9' ||
-		'\'' <= b && b <= ')' ||
-		'+' <= b && b <= '/' ||
-		b == ' ' ||
-		b == ':' ||
-		b == '=' ||
-		b == '?' ||
-		// This is technically not allowed in a PrintableString.
-		// However, x509 certificates with wildcard strings don't
-		// always use the correct string type so we permit it.
-		(bool(asterisk) && b == '*') ||
-		// This is not technically allowed either. However, not
-		// only is it relatively common, but there are also a
-		// handful of CA certificates that contain it. At least
-		// one of which will not expire until 2027.
-		(bool(ampersand) && b == '&')
-}
-
-// IA5String
-
-// parseIA5String parses an ASN.1 IA5String (ASCII string) from the given
-// byte slice and returns it.
-func parseIA5String(bytes []byte) (ret string, err error) {
-	for _, b := range bytes {
-		if b >= utf8.RuneSelf {
-			err = SyntaxError{"IA5String contains invalid character"}
-			return
-		}
-	}
-	ret = string(bytes)
-	return
-}
-
-// T61String
-
-// parseT61String parses an ASN.1 T61String (8-bit clean string) from the given
-// byte slice and returns it.
-func parseT61String(bytes []byte) (ret string, err error) {
-	return string(bytes), nil
-}
-
-// UTF8String
-
-// parseUTF8String parses an ASN.1 UTF8String (raw UTF-8) from the given byte
-// array and returns it.
-func parseUTF8String(bytes []byte) (ret string, err error) {
-	if !utf8.Valid(bytes) {
-		return "", errors.New("asn1: invalid UTF-8 string")
-	}
-	return string(bytes), nil
-}
-
-// BMPString
-
-// parseBMPString parses an ASN.1 BMPString (Basic Multilingual Plane of
-// ISO/IEC/ITU 10646-1) from the given byte slice and returns it.
-func parseBMPString(bmpString []byte) (string, error) {
-	if len(bmpString)%2 != 0 {
-		return "", errors.New("pkcs12: odd-length BMP string")
-	}
-
-	// Strip terminator if present.
-	if l := len(bmpString); l >= 2 && bmpString[l-1] == 0 && bmpString[l-2] == 0 {
-		bmpString = bmpString[:l-2]
-	}
-
-	s := make([]uint16, 0, len(bmpString)/2)
-	for len(bmpString) > 0 {
-		s = append(s, uint16(bmpString[0])<<8+uint16(bmpString[1]))
-		bmpString = bmpString[2:]
-	}
-
-	return string(utf16.Decode(s)), nil
-}
-
-// A RawValue represents an undecoded ASN.1 object.
-type RawValue struct {
-	Class, Tag int
-	IsCompound bool
-	Bytes      []byte
-	FullBytes  []byte // includes the tag and length
-}
-
-// RawContent is used to signal that the undecoded, DER data needs to be
-// preserved for a struct. To use it, the first field of the struct must have
-// this type. It's an error for any of the other fields to have this type.
-type RawContent []byte
-
-// Tagging
-
-// parseTagAndLength parses an ASN.1 tag and length pair from the given offset
-// into a byte slice. It returns the parsed data and the new offset. SET and
-// SET OF (tag 17) are mapped to SEQUENCE and SEQUENCE OF (tag 16) since we
-// don't distinguish between ordered and unordered objects in this code.
-func parseTagAndLength(bytes []byte, initOffset int) (ret tagAndLength, offset int, err error) {
-	offset = initOffset
-	// parseTagAndLength should not be called without at least a single
-	// byte to read. Thus this check is for robustness:
-	if offset >= len(bytes) {
-		err = errors.New("asn1: internal error in parseTagAndLength")
-		return
-	}
-	b := bytes[offset]
-	offset++
-	ret.class = int(b >> 6)
-	ret.isCompound = b&0x20 == 0x20
-	ret.tag = int(b & 0x1f)
-
-	// If the bottom five bits are set, then the tag number is actually base 128
-	// encoded afterwards
-	if ret.tag == 0x1f {
-		ret.tag, offset, err = parseBase128Int(bytes, offset)
-		if err != nil {
-			return
-		}
-		// Tags should be encoded in minimal form.
-		if ret.tag < 0x1f {
-			err = SyntaxError{"non-minimal tag"}
-			return
-		}
-	}
-	if offset >= len(bytes) {
-		err = SyntaxError{"truncated tag or length"}
-		return
-	}
-	b = bytes[offset]
-	offset++
-	if b&0x80 == 0 {
-		// The length is encoded in the bottom 7 bits.
-		ret.length = int(b & 0x7f)
-	} else {
-		// Bottom 7 bits give the number of length bytes to follow.
-		numBytes := int(b & 0x7f)
-		if numBytes == 0 {
-			err = SyntaxError{"indefinite length found (not DER)"}
-			return
-		}
-		ret.length = 0
-		for i := 0; i < numBytes; i++ {
-			if offset >= len(bytes) {
-				err = SyntaxError{"truncated tag or length"}
-				return
-			}
-			b = bytes[offset]
-			offset++
-			if ret.length >= 1<<23 {
-				// We can't shift ret.length up without
-				// overflowing.
-				err = StructuralError{"length too large"}
-				return
-			}
-			ret.length <<= 8
-			ret.length |= int(b)
-			if ret.length == 0 {
-				// DER requires that lengths be minimal.
-				err = StructuralError{"superfluous leading zeros in length"}
-				return
-			}
-		}
-		// Short lengths must be encoded in short form.
-		if ret.length < 0x80 {
-			err = StructuralError{"non-minimal length"}
-			return
-		}
-	}
-
-	return
-}
-
-// parseSequenceOf is used for SEQUENCE OF and SET OF values. It tries to parse
-// a number of ASN.1 values from the given byte slice and returns them as a
-// slice of Go values of the given type.
-func parseSequenceOf(bytes []byte, sliceType reflect.Type, elemType reflect.Type) (ret reflect.Value, err error) {
-	matchAny, expectedTag, compoundType, ok := getUniversalType(elemType)
-	if !ok {
-		err = StructuralError{"unknown Go type for slice"}
-		return
-	}
-
-	// First we iterate over the input and count the number of elements,
-	// checking that the types are correct in each case.
-	numElements := 0
-	for offset := 0; offset < len(bytes); {
-		var t tagAndLength
-		t, offset, err = parseTagAndLength(bytes, offset)
-		if err != nil {
-			return
-		}
-		switch t.tag {
-		case TagIA5String, TagGeneralString, TagT61String, TagUTF8String, TagNumericString, TagBMPString:
-			// We pretend that various other string types are
-			// PRINTABLE STRINGs so that a sequence of them can be
-			// parsed into a []string.
-			t.tag = TagPrintableString
-		case TagGeneralizedTime, TagUTCTime:
-			// Likewise, both time types are treated the same.
-			t.tag = TagUTCTime
-		}
-
-		if !matchAny && (t.class != ClassUniversal || t.isCompound != compoundType || t.tag != expectedTag) {
-			err = StructuralError{"sequence tag mismatch"}
-			return
-		}
-		if invalidLength(offset, t.length, len(bytes)) {
-			err = SyntaxError{"truncated sequence"}
-			return
-		}
-		offset += t.length
-		numElements++
-	}
-	ret = reflect.MakeSlice(sliceType, numElements, numElements)
-	params := fieldParameters{}
-	offset := 0
-	for i := 0; i < numElements; i++ {
-		offset, err = parseField(ret.Index(i), bytes, offset, params)
-		if err != nil {
-			return
-		}
-	}
-	return
-}
-
-var (
-	bitStringType        = reflect.TypeOf(BitString{})
-	objectIdentifierType = reflect.TypeOf(ObjectIdentifier{})
-	enumeratedType       = reflect.TypeOf(Enumerated(0))
-	flagType             = reflect.TypeOf(Flag(false))
-	timeType             = reflect.TypeOf(time.Time{})
-	rawValueType         = reflect.TypeOf(RawValue{})
-	rawContentsType      = reflect.TypeOf(RawContent(nil))
-	bigIntType           = reflect.TypeOf(new(big.Int))
-)
-
-// invalidLength reports whether offset + length > sliceLength, or if the
-// addition would overflow.
-func invalidLength(offset, length, sliceLength int) bool {
-	return offset+length < offset || offset+length > sliceLength
-}
-
-// parseField is the main parsing function. Given a byte slice and an offset
-// into the array, it will try to parse a suitable ASN.1 value out and store it
-// in the given Value.
-func parseField(v reflect.Value, bytes []byte, initOffset int, params fieldParameters) (offset int, err error) {
-	offset = initOffset
-	fieldType := v.Type()
-
-	// If we have run out of data, it may be that there are optional elements at the end.
-	if offset == len(bytes) {
-		if !setDefaultValue(v, params) {
-			err = SyntaxError{"sequence truncated"}
-		}
-		return
-	}
-
-	// Deal with the ANY type.
-	if ifaceType := fieldType; ifaceType.Kind() == reflect.Interface && ifaceType.NumMethod() == 0 {
-		var t tagAndLength
-		t, offset, err = parseTagAndLength(bytes, offset)
-		if err != nil {
-			return
-		}
-		if invalidLength(offset, t.length, len(bytes)) {
-			err = SyntaxError{"data truncated"}
-			return
-		}
-		var result any
-		if !t.isCompound && t.class == ClassUniversal {
-			innerBytes := bytes[offset : offset+t.length]
-			switch t.tag {
-			case TagPrintableString:
-				result, err = parsePrintableString(innerBytes)
-			case TagNumericString:
-				result, err = parseNumericString(innerBytes)
-			case TagIA5String:
-				result, err = parseIA5String(innerBytes)
-			case TagT61String:
-				result, err = parseT61String(innerBytes)
-			case TagUTF8String:
-				result, err = parseUTF8String(innerBytes)
-			case TagInteger:
-				result, err = parseInt64(innerBytes)
-			case TagBitString:
-				result, err = parseBitString(innerBytes)
-			case TagOID:
-				result, err = parseObjectIdentifier(innerBytes)
-			case TagUTCTime:
-				result, err = parseUTCTime(innerBytes)
-			case TagGeneralizedTime:
-				result, err = parseGeneralizedTime(innerBytes)
-			case TagOctetString:
-				result = innerBytes
-			case TagBMPString:
-				result, err = parseBMPString(innerBytes)
-			default:
-				// If we don't know how to handle the type, we just leave Value as nil.
-			}
-		}
-		offset += t.length
-		if err != nil {
-			return
-		}
-		if result != nil {
-			v.Set(reflect.ValueOf(result))
-		}
-		return
-	}
-
-	t, offset, err := parseTagAndLength(bytes, offset)
-	if err != nil {
-		return
-	}
-	if params.explicit {
-		expectedClass := ClassContextSpecific
-		if params.application {
-			expectedClass = ClassApplication
-		}
-		if offset == len(bytes) {
-			err = StructuralError{"explicit tag has no child"}
-			return
-		}
-		if t.class == expectedClass && t.tag == *params.tag && (t.length == 0 || t.isCompound) {
-			if fieldType == rawValueType {
-				// The inner element should not be parsed for RawValues.
-			} else if t.length > 0 {
-				t, offset, err = parseTagAndLength(bytes, offset)
-				if err != nil {
-					return
-				}
-			} else {
-				if fieldType != flagType {
-					err = StructuralError{"zero length explicit tag was not an asn1.Flag"}
-					return
-				}
-				v.SetBool(true)
-				return
-			}
-		} else {
-			// The tags didn't match, it might be an optional element.
-			ok := setDefaultValue(v, params)
-			if ok {
-				offset = initOffset
-			} else {
-				err = StructuralError{"explicitly tagged member didn't match"}
-			}
-			return
-		}
-	}
-
-	matchAny, universalTag, compoundType, ok1 := getUniversalType(fieldType)
-	if !ok1 {
-		err = StructuralError{fmt.Sprintf("unknown Go type: %v", fieldType)}
-		return
-	}
-
-	// Special case for strings: all the ASN.1 string types map to the Go
-	// type string. getUniversalType returns the tag for PrintableString
-	// when it sees a string, so if we see a different string type on the
-	// wire, we change the universal type to match.
-	if universalTag == TagPrintableString {
-		if t.class == ClassUniversal {
-			switch t.tag {
-			case TagIA5String, TagGeneralString, TagT61String, TagUTF8String, TagNumericString, TagBMPString:
-				universalTag = t.tag
-			}
-		} else if params.stringType != 0 {
-			universalTag = params.stringType
-		}
-	}
-
-	// Special case for time: UTCTime and GeneralizedTime both map to the
-	// Go type time.Time.
-	if universalTag == TagUTCTime && t.tag == TagGeneralizedTime && t.class == ClassUniversal {
-		universalTag = TagGeneralizedTime
-	}
-
-	if params.set {
-		universalTag = TagSet
-	}
-
-	matchAnyClassAndTag := matchAny
-	expectedClass := ClassUniversal
-	expectedTag := universalTag
-
-	if !params.explicit && params.tag != nil {
-		expectedClass = ClassContextSpecific
-		expectedTag = *params.tag
-		matchAnyClassAndTag = false
-	}
-
-	if !params.explicit && params.application && params.tag != nil {
-		expectedClass = ClassApplication
-		expectedTag = *params.tag
-		matchAnyClassAndTag = false
-	}
-
-	if !params.explicit && params.private && params.tag != nil {
-		expectedClass = ClassPrivate
-		expectedTag = *params.tag
-		matchAnyClassAndTag = false
-	}
-
-	// We have unwrapped any explicit tagging at this point.
-	if !matchAnyClassAndTag && (t.class != expectedClass || t.tag != expectedTag) ||
-		(!matchAny && t.isCompound != compoundType) {
-		// Tags don't match. Again, it could be an optional element.
-		ok := setDefaultValue(v, params)
-		if ok {
-			offset = initOffset
-		} else {
-			err = StructuralError{fmt.Sprintf("tags don't match (%d vs %+v) %+v %s @%d", expectedTag, t, params, fieldType.Name(), offset)}
-		}
-		return
-	}
-	if invalidLength(offset, t.length, len(bytes)) {
-		err = SyntaxError{"data truncated"}
-		return
-	}
-	innerBytes := bytes[offset : offset+t.length]
-	offset += t.length
-
-	// We deal with the structures defined in this package first.
-	switch v := v.Addr().Interface().(type) {
-	case *RawValue:
-		*v = RawValue{t.class, t.tag, t.isCompound, innerBytes, bytes[initOffset:offset]}
-		return
-	case *ObjectIdentifier:
-		*v, err = parseObjectIdentifier(innerBytes)
-		return
-	case *BitString:
-		*v, err = parseBitString(innerBytes)
-		return
-	case *time.Time:
-		if universalTag == TagUTCTime {
-			*v, err = parseUTCTime(innerBytes)
-			return
-		}
-		*v, err = parseGeneralizedTime(innerBytes)
-		return
-	case *Enumerated:
-		parsedInt, err1 := parseInt32(innerBytes)
-		if err1 == nil {
-			*v = Enumerated(parsedInt)
-		}
-		err = err1
-		return
-	case *Flag:
-		*v = true
-		return
-	case **big.Int:
-		parsedInt, err1 := parseBigInt(innerBytes)
-		if err1 == nil {
-			*v = parsedInt
-		}
-		err = err1
-		return
-	}
-	switch val := v; val.Kind() {
-	case reflect.Bool:
-		parsedBool, err1 := parseBool(innerBytes)
-		if err1 == nil {
-			val.SetBool(parsedBool)
-		}
-		err = err1
-		return
-	case reflect.Int, reflect.Int32, reflect.Int64:
-		if val.Type().Size() == 4 {
-			parsedInt, err1 := parseInt32(innerBytes)
-			if err1 == nil {
-				val.SetInt(int64(parsedInt))
-			}
-			err = err1
-		} else {
-			parsedInt, err1 := parseInt64(innerBytes)
-			if err1 == nil {
-				val.SetInt(parsedInt)
-			}
-			err = err1
-		}
-		return
-	// TODO(dfc) Add support for the remaining integer types
-	case reflect.Struct:
-		structType := fieldType
-
-		for i := 0; i < structType.NumField(); i++ {
-			if !structType.Field(i).IsExported() {
-				err = StructuralError{"struct contains unexported fields"}
-				return
-			}
-		}
-
-		if structType.NumField() > 0 &&
-			structType.Field(0).Type == rawContentsType {
-			bytes := bytes[initOffset:offset]
-			val.Field(0).Set(reflect.ValueOf(RawContent(bytes)))
-		}
-
-		innerOffset := 0
-		for i := 0; i < structType.NumField(); i++ {
-			field := structType.Field(i)
-			if i == 0 && field.Type == rawContentsType {
-				continue
-			}
-			innerOffset, err = parseField(val.Field(i), innerBytes, innerOffset, parseFieldParameters(field.Tag.Get("asn1")))
-			if err != nil {
-				return
-			}
-		}
-		// We allow extra bytes at the end of the SEQUENCE because
-		// adding elements to the end has been used in X.509 as the
-		// version numbers have increased.
-		return
-	case reflect.Slice:
-		sliceType := fieldType
-		if sliceType.Elem().Kind() == reflect.Uint8 {
-			val.Set(reflect.MakeSlice(sliceType, len(innerBytes), len(innerBytes)))
-			reflect.Copy(val, reflect.ValueOf(innerBytes))
-			return
-		}
-		newSlice, err1 := parseSequenceOf(innerBytes, sliceType, sliceType.Elem())
-		if err1 == nil {
-			val.Set(newSlice)
-		}
-		err = err1
-		return
-	case reflect.String:
-		var v string
-		switch universalTag {
-		case TagPrintableString:
-			v, err = parsePrintableString(innerBytes)
-		case TagNumericString:
-			v, err = parseNumericString(innerBytes)
-		case TagIA5String:
-			v, err = parseIA5String(innerBytes)
-		case TagT61String:
-			v, err = parseT61String(innerBytes)
-		case TagUTF8String:
-			v, err = parseUTF8String(innerBytes)
-		case TagGeneralString:
-			// GeneralString is specified in ISO-2022/ECMA-35,
-			// A brief review suggests that it includes structures
-			// that allow the encoding to change midstring and
-			// such. We give up and pass it as an 8-bit string.
-			v, err = parseT61String(innerBytes)
-		case TagBMPString:
-			v, err = parseBMPString(innerBytes)
-
-		default:
-			err = SyntaxError{fmt.Sprintf("internal error: unknown string type %d", universalTag)}
-		}
-		if err == nil {
-			val.SetString(v)
-		}
-		return
-	}
-	err = StructuralError{"unsupported: " + v.Type().String()}
-	return
-}
-
-// canHaveDefaultValue reports whether k is a Kind that we will set a default
-// value for. (A signed integer, essentially.)
-func canHaveDefaultValue(k reflect.Kind) bool {
-	switch k {
-	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
-		return true
-	}
-
-	return false
-}
-
-// setDefaultValue is used to install a default value, from a tag string, into
-// a Value. It is successful if the field was optional, even if a default value
-// wasn't provided or it failed to install it into the Value.
-func setDefaultValue(v reflect.Value, params fieldParameters) (ok bool) {
-	if !params.optional {
-		return
-	}
-	ok = true
-	if params.defaultValue == nil {
-		return
-	}
-	if canHaveDefaultValue(v.Kind()) {
-		v.SetInt(*params.defaultValue)
-	}
-	return
-}
-
-// Unmarshal parses the DER-encoded ASN.1 data structure b
-// and uses the reflect package to fill in an arbitrary value pointed at by val.
-// Because Unmarshal uses the reflect package, the structs
-// being written to must use upper case field names. If val
-// is nil or not a pointer, Unmarshal returns an error.
-//
-// After parsing b, any bytes that were leftover and not used to fill
-// val will be returned in rest. When parsing a SEQUENCE into a struct,
-// any trailing elements of the SEQUENCE that do not have matching
-// fields in val will not be included in rest, as these are considered
-// valid elements of the SEQUENCE and not trailing data.
-//
-// An ASN.1 INTEGER can be written to an int, int32, int64,
-// or *big.Int (from the math/big package).
-// If the encoded value does not fit in the Go type,
-// Unmarshal returns a parse error.
-//
-// An ASN.1 BIT STRING can be written to a BitString.
-//
-// An ASN.1 OCTET STRING can be written to a []byte.
-//
-// An ASN.1 OBJECT IDENTIFIER can be written to an
-// ObjectIdentifier.
-//
-// An ASN.1 ENUMERATED can be written to an Enumerated.
-//
-// An ASN.1 UTCTIME or GENERALIZEDTIME can be written to a time.Time.
-//
-// An ASN.1 PrintableString, IA5String, or NumericString can be written to a string.
-//
-// Any of the above ASN.1 values can be written to an interface{}.
-// The value stored in the interface has the corresponding Go type.
-// For integers, that type is int64.
-//
-// An ASN.1 SEQUENCE OF x or SET OF x can be written
-// to a slice if an x can be written to the slice's element type.
-//
-// An ASN.1 SEQUENCE or SET can be written to a struct
-// if each of the elements in the sequence can be
-// written to the corresponding element in the struct.
-//
-// The following tags on struct fields have special meaning to Unmarshal:
-//
-//	application specifies that an APPLICATION tag is used
-//	private     specifies that a PRIVATE tag is used
-//	default:x   sets the default value for optional integer fields (only used if optional is also present)
-//	explicit    specifies that an additional, explicit tag wraps the implicit one
-//	optional    marks the field as ASN.1 OPTIONAL
-//	set         causes a SET, rather than a SEQUENCE type to be expected
-//	tag:x       specifies the ASN.1 tag number; implies ASN.1 CONTEXT SPECIFIC
-//
-// When decoding an ASN.1 value with an IMPLICIT tag into a string field,
-// Unmarshal will default to a PrintableString, which doesn't support
-// characters such as '@' and '&'. To force other encodings, use the following
-// tags:
-//
-//	ia5     causes strings to be unmarshaled as ASN.1 IA5String values
-//	numeric causes strings to be unmarshaled as ASN.1 NumericString values
-//	utf8    causes strings to be unmarshaled as ASN.1 UTF8String values
-//
-// If the type of the first field of a structure is RawContent then the raw
-// ASN1 contents of the struct will be stored in it.
-//
-// If the name of a slice type ends with "SET" then it's treated as if
-// the "set" tag was set on it. This results in interpreting the type as a
-// SET OF x rather than a SEQUENCE OF x. This can be used with nested slices
-// where a struct tag cannot be given.
-//
-// Other ASN.1 types are not supported; if it encounters them,
-// Unmarshal returns a parse error.
-func Unmarshal(b []byte, val any) (rest []byte, err error) {
-	return UnmarshalWithParams(b, val, "")
-}
-
-// An invalidUnmarshalError describes an invalid argument passed to Unmarshal.
-// (The argument to Unmarshal must be a non-nil pointer.)
-type invalidUnmarshalError struct {
-	Type reflect.Type
-}
-
-func (e *invalidUnmarshalError) Error() string {
-	if e.Type == nil {
-		return "asn1: Unmarshal recipient value is nil"
-	}
-
-	if e.Type.Kind() != reflect.Pointer {
-		return "asn1: Unmarshal recipient value is non-pointer " + e.Type.String()
-	}
-	return "asn1: Unmarshal recipient value is nil " + e.Type.String()
-}
-
-// UnmarshalWithParams allows field parameters to be specified for the
-// top-level element. The form of the params is the same as the field tags.
-func UnmarshalWithParams(b []byte, val any, params string) (rest []byte, err error) {
-	v := reflect.ValueOf(val)
-	if v.Kind() != reflect.Pointer || v.IsNil() {
-		return nil, &invalidUnmarshalError{reflect.TypeOf(val)}
-	}
-	offset, err := parseField(v.Elem(), b, 0, parseFieldParameters(params))
-	if err != nil {
-		return nil, err
-	}
-	return b[offset:], nil
-}
diff --git a/contrib/go/_std_1.18/src/encoding/binary/binary.go b/contrib/go/_std_1.18/src/encoding/binary/binary.go
deleted file mode 100644
index ee933461ee..0000000000
--- a/contrib/go/_std_1.18/src/encoding/binary/binary.go
+++ /dev/null
@@ -1,737 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package binary implements simple translation between numbers and byte
-// sequences and encoding and decoding of varints.
-//
-// Numbers are translated by reading and writing fixed-size values.
-// A fixed-size value is either a fixed-size arithmetic
-// type (bool, int8, uint8, int16, float32, complex64, ...)
-// or an array or struct containing only fixed-size values.
-//
-// The varint functions encode and decode single integer values using
-// a variable-length encoding; smaller values require fewer bytes.
-// For a specification, see
-// https://developers.google.com/protocol-buffers/docs/encoding.
-//
-// This package favors simplicity over efficiency. Clients that require
-// high-performance serialization, especially for large data structures,
-// should look at more advanced solutions such as the encoding/gob
-// package or protocol buffers.
-package binary
-
-import (
-	"errors"
-	"io"
-	"math"
-	"reflect"
-	"sync"
-)
-
-// A ByteOrder specifies how to convert byte sequences into
-// 16-, 32-, or 64-bit unsigned integers.
-type ByteOrder interface {
-	Uint16([]byte) uint16
-	Uint32([]byte) uint32
-	Uint64([]byte) uint64
-	PutUint16([]byte, uint16)
-	PutUint32([]byte, uint32)
-	PutUint64([]byte, uint64)
-	String() string
-}
-
-// LittleEndian is the little-endian implementation of ByteOrder.
-var LittleEndian littleEndian
-
-// BigEndian is the big-endian implementation of ByteOrder.
-var BigEndian bigEndian
-
-type littleEndian struct{}
-
-func (littleEndian) Uint16(b []byte) uint16 {
-	_ = b[1] // bounds check hint to compiler; see golang.org/issue/14808
-	return uint16(b[0]) | uint16(b[1])<<8
-}
-
-func (littleEndian) PutUint16(b []byte, v uint16) {
-	_ = b[1] // early bounds check to guarantee safety of writes below
-	b[0] = byte(v)
-	b[1] = byte(v >> 8)
-}
-
-func (littleEndian) Uint32(b []byte) uint32 {
-	_ = b[3] // bounds check hint to compiler; see golang.org/issue/14808
-	return uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24
-}
-
-func (littleEndian) PutUint32(b []byte, v uint32) {
-	_ = b[3] // early bounds check to guarantee safety of writes below
-	b[0] = byte(v)
-	b[1] = byte(v >> 8)
-	b[2] = byte(v >> 16)
-	b[3] = byte(v >> 24)
-}
-
-func (littleEndian) Uint64(b []byte) uint64 {
-	_ = b[7] // bounds check hint to compiler; see golang.org/issue/14808
-	return uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 |
-		uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56
-}
-
-func (littleEndian) PutUint64(b []byte, v uint64) {
-	_ = b[7] // early bounds check to guarantee safety of writes below
-	b[0] = byte(v)
-	b[1] = byte(v >> 8)
-	b[2] = byte(v >> 16)
-	b[3] = byte(v >> 24)
-	b[4] = byte(v >> 32)
-	b[5] = byte(v >> 40)
-	b[6] = byte(v >> 48)
-	b[7] = byte(v >> 56)
-}
-
-func (littleEndian) String() string { return "LittleEndian" }
-
-func (littleEndian) GoString() string { return "binary.LittleEndian" }
-
-type bigEndian struct{}
-
-func (bigEndian) Uint16(b []byte) uint16 {
-	_ = b[1] // bounds check hint to compiler; see golang.org/issue/14808
-	return uint16(b[1]) | uint16(b[0])<<8
-}
-
-func (bigEndian) PutUint16(b []byte, v uint16) {
-	_ = b[1] // early bounds check to guarantee safety of writes below
-	b[0] = byte(v >> 8)
-	b[1] = byte(v)
-}
-
-func (bigEndian) Uint32(b []byte) uint32 {
-	_ = b[3] // bounds check hint to compiler; see golang.org/issue/14808
-	return uint32(b[3]) | uint32(b[2])<<8 | uint32(b[1])<<16 | uint32(b[0])<<24
-}
-
-func (bigEndian) PutUint32(b []byte, v uint32) {
-	_ = b[3] // early bounds check to guarantee safety of writes below
-	b[0] = byte(v >> 24)
-	b[1] = byte(v >> 16)
-	b[2] = byte(v >> 8)
-	b[3] = byte(v)
-}
-
-func (bigEndian) Uint64(b []byte) uint64 {
-	_ = b[7] // bounds check hint to compiler; see golang.org/issue/14808
-	return uint64(b[7]) | uint64(b[6])<<8 | uint64(b[5])<<16 | uint64(b[4])<<24 |
-		uint64(b[3])<<32 | uint64(b[2])<<40 | uint64(b[1])<<48 | uint64(b[0])<<56
-}
-
-func (bigEndian) PutUint64(b []byte, v uint64) {
-	_ = b[7] // early bounds check to guarantee safety of writes below
-	b[0] = byte(v >> 56)
-	b[1] = byte(v >> 48)
-	b[2] = byte(v >> 40)
-	b[3] = byte(v >> 32)
-	b[4] = byte(v >> 24)
-	b[5] = byte(v >> 16)
-	b[6] = byte(v >> 8)
-	b[7] = byte(v)
-}
-
-func (bigEndian) String() string { return "BigEndian" }
-
-func (bigEndian) GoString() string { return "binary.BigEndian" }
-
-// Read reads structured binary data from r into data.
-// Data must be a pointer to a fixed-size value or a slice
-// of fixed-size values.
-// Bytes read from r are decoded using the specified byte order
-// and written to successive fields of the data.
-// When decoding boolean values, a zero byte is decoded as false, and
-// any other non-zero byte is decoded as true.
-// When reading into structs, the field data for fields with
-// blank (_) field names is skipped; i.e., blank field names
-// may be used for padding.
-// When reading into a struct, all non-blank fields must be exported
-// or Read may panic.
-//
-// The error is EOF only if no bytes were read.
-// If an EOF happens after reading some but not all the bytes,
-// Read returns ErrUnexpectedEOF.
-func Read(r io.Reader, order ByteOrder, data any) error {
-	// Fast path for basic types and slices.
-	if n := intDataSize(data); n != 0 {
-		bs := make([]byte, n)
-		if _, err := io.ReadFull(r, bs); err != nil {
-			return err
-		}
-		switch data := data.(type) {
-		case *bool:
-			*data = bs[0] != 0
-		case *int8:
-			*data = int8(bs[0])
-		case *uint8:
-			*data = bs[0]
-		case *int16:
-			*data = int16(order.Uint16(bs))
-		case *uint16:
-			*data = order.Uint16(bs)
-		case *int32:
-			*data = int32(order.Uint32(bs))
-		case *uint32:
-			*data = order.Uint32(bs)
-		case *int64:
-			*data = int64(order.Uint64(bs))
-		case *uint64:
-			*data = order.Uint64(bs)
-		case *float32:
-			*data = math.Float32frombits(order.Uint32(bs))
-		case *float64:
-			*data = math.Float64frombits(order.Uint64(bs))
-		case []bool:
-			for i, x := range bs { // Easier to loop over the input for 8-bit values.
-				data[i] = x != 0
-			}
-		case []int8:
-			for i, x := range bs {
-				data[i] = int8(x)
-			}
-		case []uint8:
-			copy(data, bs)
-		case []int16:
-			for i := range data {
-				data[i] = int16(order.Uint16(bs[2*i:]))
-			}
-		case []uint16:
-			for i := range data {
-				data[i] = order.Uint16(bs[2*i:])
-			}
-		case []int32:
-			for i := range data {
-				data[i] = int32(order.Uint32(bs[4*i:]))
-			}
-		case []uint32:
-			for i := range data {
-				data[i] = order.Uint32(bs[4*i:])
-			}
-		case []int64:
-			for i := range data {
-				data[i] = int64(order.Uint64(bs[8*i:]))
-			}
-		case []uint64:
-			for i := range data {
-				data[i] = order.Uint64(bs[8*i:])
-			}
-		case []float32:
-			for i := range data {
-				data[i] = math.Float32frombits(order.Uint32(bs[4*i:]))
-			}
-		case []float64:
-			for i := range data {
-				data[i] = math.Float64frombits(order.Uint64(bs[8*i:]))
-			}
-		default:
-			n = 0 // fast path doesn't apply
-		}
-		if n != 0 {
-			return nil
-		}
-	}
-
-	// Fallback to reflect-based decoding.
-	v := reflect.ValueOf(data)
-	size := -1
-	switch v.Kind() {
-	case reflect.Pointer:
-		v = v.Elem()
-		size = dataSize(v)
-	case reflect.Slice:
-		size = dataSize(v)
-	}
-	if size < 0 {
-		return errors.New("binary.Read: invalid type " + reflect.TypeOf(data).String())
-	}
-	d := &decoder{order: order, buf: make([]byte, size)}
-	if _, err := io.ReadFull(r, d.buf); err != nil {
-		return err
-	}
-	d.value(v)
-	return nil
-}
-
-// Write writes the binary representation of data into w.
-// Data must be a fixed-size value or a slice of fixed-size
-// values, or a pointer to such data.
-// Boolean values encode as one byte: 1 for true, and 0 for false.
-// Bytes written to w are encoded using the specified byte order
-// and read from successive fields of the data.
-// When writing structs, zero values are written for fields
-// with blank (_) field names.
-func Write(w io.Writer, order ByteOrder, data any) error {
-	// Fast path for basic types and slices.
-	if n := intDataSize(data); n != 0 {
-		bs := make([]byte, n)
-		switch v := data.(type) {
-		case *bool:
-			if *v {
-				bs[0] = 1
-			} else {
-				bs[0] = 0
-			}
-		case bool:
-			if v {
-				bs[0] = 1
-			} else {
-				bs[0] = 0
-			}
-		case []bool:
-			for i, x := range v {
-				if x {
-					bs[i] = 1
-				} else {
-					bs[i] = 0
-				}
-			}
-		case *int8:
-			bs[0] = byte(*v)
-		case int8:
-			bs[0] = byte(v)
-		case []int8:
-			for i, x := range v {
-				bs[i] = byte(x)
-			}
-		case *uint8:
-			bs[0] = *v
-		case uint8:
-			bs[0] = v
-		case []uint8:
-			bs = v
-		case *int16:
-			order.PutUint16(bs, uint16(*v))
-		case int16:
-			order.PutUint16(bs, uint16(v))
-		case []int16:
-			for i, x := range v {
-				order.PutUint16(bs[2*i:], uint16(x))
-			}
-		case *uint16:
-			order.PutUint16(bs, *v)
-		case uint16:
-			order.PutUint16(bs, v)
-		case []uint16:
-			for i, x := range v {
-				order.PutUint16(bs[2*i:], x)
-			}
-		case *int32:
-			order.PutUint32(bs, uint32(*v))
-		case int32:
-			order.PutUint32(bs, uint32(v))
-		case []int32:
-			for i, x := range v {
-				order.PutUint32(bs[4*i:], uint32(x))
-			}
-		case *uint32:
-			order.PutUint32(bs, *v)
-		case uint32:
-			order.PutUint32(bs, v)
-		case []uint32:
-			for i, x := range v {
-				order.PutUint32(bs[4*i:], x)
-			}
-		case *int64:
-			order.PutUint64(bs, uint64(*v))
-		case int64:
-			order.PutUint64(bs, uint64(v))
-		case []int64:
-			for i, x := range v {
-				order.PutUint64(bs[8*i:], uint64(x))
-			}
-		case *uint64:
-			order.PutUint64(bs, *v)
-		case uint64:
-			order.PutUint64(bs, v)
-		case []uint64:
-			for i, x := range v {
-				order.PutUint64(bs[8*i:], x)
-			}
-		case *float32:
-			order.PutUint32(bs, math.Float32bits(*v))
-		case float32:
-			order.PutUint32(bs, math.Float32bits(v))
-		case []float32:
-			for i, x := range v {
-				order.PutUint32(bs[4*i:], math.Float32bits(x))
-			}
-		case *float64:
-			order.PutUint64(bs, math.Float64bits(*v))
-		case float64:
-			order.PutUint64(bs, math.Float64bits(v))
-		case []float64:
-			for i, x := range v {
-				order.PutUint64(bs[8*i:], math.Float64bits(x))
-			}
-		}
-		_, err := w.Write(bs)
-		return err
-	}
-
-	// Fallback to reflect-based encoding.
-	v := reflect.Indirect(reflect.ValueOf(data))
-	size := dataSize(v)
-	if size < 0 {
-		return errors.New("binary.Write: invalid type " + reflect.TypeOf(data).String())
-	}
-	buf := make([]byte, size)
-	e := &encoder{order: order, buf: buf}
-	e.value(v)
-	_, err := w.Write(buf)
-	return err
-}
-
-// Size returns how many bytes Write would generate to encode the value v, which
-// must be a fixed-size value or a slice of fixed-size values, or a pointer to such data.
-// If v is neither of these, Size returns -1.
-func Size(v any) int {
-	return dataSize(reflect.Indirect(reflect.ValueOf(v)))
-}
-
-var structSize sync.Map // map[reflect.Type]int
-
-// dataSize returns the number of bytes the actual data represented by v occupies in memory.
-// For compound structures, it sums the sizes of the elements. Thus, for instance, for a slice
-// it returns the length of the slice times the element size and does not count the memory
-// occupied by the header. If the type of v is not acceptable, dataSize returns -1.
-func dataSize(v reflect.Value) int {
-	switch v.Kind() {
-	case reflect.Slice:
-		if s := sizeof(v.Type().Elem()); s >= 0 {
-			return s * v.Len()
-		}
-		return -1
-
-	case reflect.Struct:
-		t := v.Type()
-		if size, ok := structSize.Load(t); ok {
-			return size.(int)
-		}
-		size := sizeof(t)
-		structSize.Store(t, size)
-		return size
-
-	default:
-		return sizeof(v.Type())
-	}
-}
-
-// sizeof returns the size >= 0 of variables for the given type or -1 if the type is not acceptable.
-func sizeof(t reflect.Type) int {
-	switch t.Kind() {
-	case reflect.Array:
-		if s := sizeof(t.Elem()); s >= 0 {
-			return s * t.Len()
-		}
-
-	case reflect.Struct:
-		sum := 0
-		for i, n := 0, t.NumField(); i < n; i++ {
-			s := sizeof(t.Field(i).Type)
-			if s < 0 {
-				return -1
-			}
-			sum += s
-		}
-		return sum
-
-	case reflect.Bool,
-		reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64,
-		reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64,
-		reflect.Float32, reflect.Float64, reflect.Complex64, reflect.Complex128:
-		return int(t.Size())
-	}
-
-	return -1
-}
-
-type coder struct {
-	order  ByteOrder
-	buf    []byte
-	offset int
-}
-
-type decoder coder
-type encoder coder
-
-func (d *decoder) bool() bool {
-	x := d.buf[d.offset]
-	d.offset++
-	return x != 0
-}
-
-func (e *encoder) bool(x bool) {
-	if x {
-		e.buf[e.offset] = 1
-	} else {
-		e.buf[e.offset] = 0
-	}
-	e.offset++
-}
-
-func (d *decoder) uint8() uint8 {
-	x := d.buf[d.offset]
-	d.offset++
-	return x
-}
-
-func (e *encoder) uint8(x uint8) {
-	e.buf[e.offset] = x
-	e.offset++
-}
-
-func (d *decoder) uint16() uint16 {
-	x := d.order.Uint16(d.buf[d.offset : d.offset+2])
-	d.offset += 2
-	return x
-}
-
-func (e *encoder) uint16(x uint16) {
-	e.order.PutUint16(e.buf[e.offset:e.offset+2], x)
-	e.offset += 2
-}
-
-func (d *decoder) uint32() uint32 {
-	x := d.order.Uint32(d.buf[d.offset : d.offset+4])
-	d.offset += 4
-	return x
-}
-
-func (e *encoder) uint32(x uint32) {
-	e.order.PutUint32(e.buf[e.offset:e.offset+4], x)
-	e.offset += 4
-}
-
-func (d *decoder) uint64() uint64 {
-	x := d.order.Uint64(d.buf[d.offset : d.offset+8])
-	d.offset += 8
-	return x
-}
-
-func (e *encoder) uint64(x uint64) {
-	e.order.PutUint64(e.buf[e.offset:e.offset+8], x)
-	e.offset += 8
-}
-
-func (d *decoder) int8() int8 { return int8(d.uint8()) }
-
-func (e *encoder) int8(x int8) { e.uint8(uint8(x)) }
-
-func (d *decoder) int16() int16 { return int16(d.uint16()) }
-
-func (e *encoder) int16(x int16) { e.uint16(uint16(x)) }
-
-func (d *decoder) int32() int32 { return int32(d.uint32()) }
-
-func (e *encoder) int32(x int32) { e.uint32(uint32(x)) }
-
-func (d *decoder) int64() int64 { return int64(d.uint64()) }
-
-func (e *encoder) int64(x int64) { e.uint64(uint64(x)) }
-
-func (d *decoder) value(v reflect.Value) {
-	switch v.Kind() {
-	case reflect.Array:
-		l := v.Len()
-		for i := 0; i < l; i++ {
-			d.value(v.Index(i))
-		}
-
-	case reflect.Struct:
-		t := v.Type()
-		l := v.NumField()
-		for i := 0; i < l; i++ {
-			// Note: Calling v.CanSet() below is an optimization.
-			// It would be sufficient to check the field name,
-			// but creating the StructField info for each field is
-			// costly (run "go test -bench=ReadStruct" and compare
-			// results when making changes to this code).
-			if v := v.Field(i); v.CanSet() || t.Field(i).Name != "_" {
-				d.value(v)
-			} else {
-				d.skip(v)
-			}
-		}
-
-	case reflect.Slice:
-		l := v.Len()
-		for i := 0; i < l; i++ {
-			d.value(v.Index(i))
-		}
-
-	case reflect.Bool:
-		v.SetBool(d.bool())
-
-	case reflect.Int8:
-		v.SetInt(int64(d.int8()))
-	case reflect.Int16:
-		v.SetInt(int64(d.int16()))
-	case reflect.Int32:
-		v.SetInt(int64(d.int32()))
-	case reflect.Int64:
-		v.SetInt(d.int64())
-
-	case reflect.Uint8:
-		v.SetUint(uint64(d.uint8()))
-	case reflect.Uint16:
-		v.SetUint(uint64(d.uint16()))
-	case reflect.Uint32:
-		v.SetUint(uint64(d.uint32()))
-	case reflect.Uint64:
-		v.SetUint(d.uint64())
-
-	case reflect.Float32:
-		v.SetFloat(float64(math.Float32frombits(d.uint32())))
-	case reflect.Float64:
-		v.SetFloat(math.Float64frombits(d.uint64()))
-
-	case reflect.Complex64:
-		v.SetComplex(complex(
-			float64(math.Float32frombits(d.uint32())),
-			float64(math.Float32frombits(d.uint32())),
-		))
-	case reflect.Complex128:
-		v.SetComplex(complex(
-			math.Float64frombits(d.uint64()),
-			math.Float64frombits(d.uint64()),
-		))
-	}
-}
-
-func (e *encoder) value(v reflect.Value) {
-	switch v.Kind() {
-	case reflect.Array:
-		l := v.Len()
-		for i := 0; i < l; i++ {
-			e.value(v.Index(i))
-		}
-
-	case reflect.Struct:
-		t := v.Type()
-		l := v.NumField()
-		for i := 0; i < l; i++ {
-			// see comment for corresponding code in decoder.value()
-			if v := v.Field(i); v.CanSet() || t.Field(i).Name != "_" {
-				e.value(v)
-			} else {
-				e.skip(v)
-			}
-		}
-
-	case reflect.Slice:
-		l := v.Len()
-		for i := 0; i < l; i++ {
-			e.value(v.Index(i))
-		}
-
-	case reflect.Bool:
-		e.bool(v.Bool())
-
-	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
-		switch v.Type().Kind() {
-		case reflect.Int8:
-			e.int8(int8(v.Int()))
-		case reflect.Int16:
-			e.int16(int16(v.Int()))
-		case reflect.Int32:
-			e.int32(int32(v.Int()))
-		case reflect.Int64:
-			e.int64(v.Int())
-		}
-
-	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
-		switch v.Type().Kind() {
-		case reflect.Uint8:
-			e.uint8(uint8(v.Uint()))
-		case reflect.Uint16:
-			e.uint16(uint16(v.Uint()))
-		case reflect.Uint32:
-			e.uint32(uint32(v.Uint()))
-		case reflect.Uint64:
-			e.uint64(v.Uint())
-		}
-
-	case reflect.Float32, reflect.Float64:
-		switch v.Type().Kind() {
-		case reflect.Float32:
-			e.uint32(math.Float32bits(float32(v.Float())))
-		case reflect.Float64:
-			e.uint64(math.Float64bits(v.Float()))
-		}
-
-	case reflect.Complex64, reflect.Complex128:
-		switch v.Type().Kind() {
-		case reflect.Complex64:
-			x := v.Complex()
-			e.uint32(math.Float32bits(float32(real(x))))
-			e.uint32(math.Float32bits(float32(imag(x))))
-		case reflect.Complex128:
-			x := v.Complex()
-			e.uint64(math.Float64bits(real(x)))
-			e.uint64(math.Float64bits(imag(x)))
-		}
-	}
-}
-
-func (d *decoder) skip(v reflect.Value) {
-	d.offset += dataSize(v)
-}
-
-func (e *encoder) skip(v reflect.Value) {
-	n := dataSize(v)
-	zero := e.buf[e.offset : e.offset+n]
-	for i := range zero {
-		zero[i] = 0
-	}
-	e.offset += n
-}
-
-// intDataSize returns the size of the data required to represent the data when encoded.
-// It returns zero if the type cannot be implemented by the fast path in Read or Write.
-func intDataSize(data any) int {
-	switch data := data.(type) {
-	case bool, int8, uint8, *bool, *int8, *uint8:
-		return 1
-	case []bool:
-		return len(data)
-	case []int8:
-		return len(data)
-	case []uint8:
-		return len(data)
-	case int16, uint16, *int16, *uint16:
-		return 2
-	case []int16:
-		return 2 * len(data)
-	case []uint16:
-		return 2 * len(data)
-	case int32, uint32, *int32, *uint32:
-		return 4
-	case []int32:
-		return 4 * len(data)
-	case []uint32:
-		return 4 * len(data)
-	case int64, uint64, *int64, *uint64:
-		return 8
-	case []int64:
-		return 8 * len(data)
-	case []uint64:
-		return 8 * len(data)
-	case float32, *float32:
-		return 4
-	case float64, *float64:
-		return 8
-	case []float32:
-		return 4 * len(data)
-	case []float64:
-		return 8 * len(data)
-	}
-	return 0
-}
diff --git a/contrib/go/_std_1.18/src/encoding/binary/varint.go b/contrib/go/_std_1.18/src/encoding/binary/varint.go
deleted file mode 100644
index 8fe20b5c45..0000000000
--- a/contrib/go/_std_1.18/src/encoding/binary/varint.go
+++ /dev/null
@@ -1,139 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package binary
-
-// This file implements "varint" encoding of 64-bit integers.
-// The encoding is:
-// - unsigned integers are serialized 7 bits at a time, starting with the
-//   least significant bits
-// - the most significant bit (msb) in each output byte indicates if there
-//   is a continuation byte (msb = 1)
-// - signed integers are mapped to unsigned integers using "zig-zag"
-//   encoding: Positive values x are written as 2*x + 0, negative values
-//   are written as 2*(^x) + 1; that is, negative numbers are complemented
-//   and whether to complement is encoded in bit 0.
-//
-// Design note:
-// At most 10 bytes are needed for 64-bit values. The encoding could
-// be more dense: a full 64-bit value needs an extra byte just to hold bit 63.
-// Instead, the msb of the previous byte could be used to hold bit 63 since we
-// know there can't be more than 64 bits. This is a trivial improvement and
-// would reduce the maximum encoding length to 9 bytes. However, it breaks the
-// invariant that the msb is always the "continuation bit" and thus makes the
-// format incompatible with a varint encoding for larger numbers (say 128-bit).
-
-import (
-	"errors"
-	"io"
-)
-
-// MaxVarintLenN is the maximum length of a varint-encoded N-bit integer.
-const (
-	MaxVarintLen16 = 3
-	MaxVarintLen32 = 5
-	MaxVarintLen64 = 10
-)
-
-// PutUvarint encodes a uint64 into buf and returns the number of bytes written.
-// If the buffer is too small, PutUvarint will panic.
-func PutUvarint(buf []byte, x uint64) int {
-	i := 0
-	for x >= 0x80 {
-		buf[i] = byte(x) | 0x80
-		x >>= 7
-		i++
-	}
-	buf[i] = byte(x)
-	return i + 1
-}
-
-// Uvarint decodes a uint64 from buf and returns that value and the
-// number of bytes read (> 0). If an error occurred, the value is 0
-// and the number of bytes n is <= 0 meaning:
-//
-// 	n == 0: buf too small
-// 	n  < 0: value larger than 64 bits (overflow)
-// 	        and -n is the number of bytes read
-//
-func Uvarint(buf []byte) (uint64, int) {
-	var x uint64
-	var s uint
-	for i, b := range buf {
-		if i == MaxVarintLen64 {
-			// Catch byte reads past MaxVarintLen64.
-			// See issue https://golang.org/issues/41185
-			return 0, -(i + 1) // overflow
-		}
-		if b < 0x80 {
-			if i == MaxVarintLen64-1 && b > 1 {
-				return 0, -(i + 1) // overflow
-			}
-			return x | uint64(b)<<s, i + 1
-		}
-		x |= uint64(b&0x7f) << s
-		s += 7
-	}
-	return 0, 0
-}
-
-// PutVarint encodes an int64 into buf and returns the number of bytes written.
-// If the buffer is too small, PutVarint will panic.
-func PutVarint(buf []byte, x int64) int {
-	ux := uint64(x) << 1
-	if x < 0 {
-		ux = ^ux
-	}
-	return PutUvarint(buf, ux)
-}
-
-// Varint decodes an int64 from buf and returns that value and the
-// number of bytes read (> 0). If an error occurred, the value is 0
-// and the number of bytes n is <= 0 with the following meaning:
-//
-// 	n == 0: buf too small
-// 	n  < 0: value larger than 64 bits (overflow)
-// 	        and -n is the number of bytes read
-//
-func Varint(buf []byte) (int64, int) {
-	ux, n := Uvarint(buf) // ok to continue in presence of error
-	x := int64(ux >> 1)
-	if ux&1 != 0 {
-		x = ^x
-	}
-	return x, n
-}
-
-var overflow = errors.New("binary: varint overflows a 64-bit integer")
-
-// ReadUvarint reads an encoded unsigned integer from r and returns it as a uint64.
-func ReadUvarint(r io.ByteReader) (uint64, error) {
-	var x uint64
-	var s uint
-	for i := 0; i < MaxVarintLen64; i++ {
-		b, err := r.ReadByte()
-		if err != nil {
-			return x, err
-		}
-		if b < 0x80 {
-			if i == MaxVarintLen64-1 && b > 1 {
-				return x, overflow
-			}
-			return x | uint64(b)<<s, nil
-		}
-		x |= uint64(b&0x7f) << s
-		s += 7
-	}
-	return x, overflow
-}
-
-// ReadVarint reads an encoded signed integer from r and returns it as an int64.
-func ReadVarint(r io.ByteReader) (int64, error) {
-	ux, err := ReadUvarint(r) // ok to continue in presence of error
-	x := int64(ux >> 1)
-	if ux&1 != 0 {
-		x = ^x
-	}
-	return x, err
-}
diff --git a/contrib/go/_std_1.18/src/encoding/csv/reader.go b/contrib/go/_std_1.18/src/encoding/csv/reader.go
deleted file mode 100644
index f860f4f25f..0000000000
--- a/contrib/go/_std_1.18/src/encoding/csv/reader.go
+++ /dev/null
@@ -1,450 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package csv reads and writes comma-separated values (CSV) files.
-// There are many kinds of CSV files; this package supports the format
-// described in RFC 4180.
-//
-// A csv file contains zero or more records of one or more fields per record.
-// Each record is separated by the newline character. The final record may
-// optionally be followed by a newline character.
-//
-//	field1,field2,field3
-//
-// White space is considered part of a field.
-//
-// Carriage returns before newline characters are silently removed.
-//
-// Blank lines are ignored. A line with only whitespace characters (excluding
-// the ending newline character) is not considered a blank line.
-//
-// Fields which start and stop with the quote character " are called
-// quoted-fields. The beginning and ending quote are not part of the
-// field.
-//
-// The source:
-//
-//	normal string,"quoted-field"
-//
-// results in the fields
-//
-//	{`normal string`, `quoted-field`}
-//
-// Within a quoted-field a quote character followed by a second quote
-// character is considered a single quote.
-//
-//	"the ""word"" is true","a ""quoted-field"""
-//
-// results in
-//
-//	{`the "word" is true`, `a "quoted-field"`}
-//
-// Newlines and commas may be included in a quoted-field
-//
-//	"Multi-line
-//	field","comma is ,"
-//
-// results in
-//
-//	{`Multi-line
-//	field`, `comma is ,`}
-package csv
-
-import (
-	"bufio"
-	"bytes"
-	"errors"
-	"fmt"
-	"io"
-	"unicode"
-	"unicode/utf8"
-)
-
-// A ParseError is returned for parsing errors.
-// Line numbers are 1-indexed and columns are 0-indexed.
-type ParseError struct {
-	StartLine int   // Line where the record starts
-	Line      int   // Line where the error occurred
-	Column    int   // Column (1-based byte index) where the error occurred
-	Err       error // The actual error
-}
-
-func (e *ParseError) Error() string {
-	if e.Err == ErrFieldCount {
-		return fmt.Sprintf("record on line %d: %v", e.Line, e.Err)
-	}
-	if e.StartLine != e.Line {
-		return fmt.Sprintf("record on line %d; parse error on line %d, column %d: %v", e.StartLine, e.Line, e.Column, e.Err)
-	}
-	return fmt.Sprintf("parse error on line %d, column %d: %v", e.Line, e.Column, e.Err)
-}
-
-func (e *ParseError) Unwrap() error { return e.Err }
-
-// These are the errors that can be returned in ParseError.Err.
-var (
-	ErrTrailingComma = errors.New("extra delimiter at end of line") // Deprecated: No longer used.
-	ErrBareQuote     = errors.New("bare \" in non-quoted-field")
-	ErrQuote         = errors.New("extraneous or missing \" in quoted-field")
-	ErrFieldCount    = errors.New("wrong number of fields")
-)
-
-var errInvalidDelim = errors.New("csv: invalid field or comment delimiter")
-
-func validDelim(r rune) bool {
-	return r != 0 && r != '"' && r != '\r' && r != '\n' && utf8.ValidRune(r) && r != utf8.RuneError
-}
-
-// A Reader reads records from a CSV-encoded file.
-//
-// As returned by NewReader, a Reader expects input conforming to RFC 4180.
-// The exported fields can be changed to customize the details before the
-// first call to Read or ReadAll.
-//
-// The Reader converts all \r\n sequences in its input to plain \n,
-// including in multiline field values, so that the returned data does
-// not depend on which line-ending convention an input file uses.
-type Reader struct {
-	// Comma is the field delimiter.
-	// It is set to comma (',') by NewReader.
-	// Comma must be a valid rune and must not be \r, \n,
-	// or the Unicode replacement character (0xFFFD).
-	Comma rune
-
-	// Comment, if not 0, is the comment character. Lines beginning with the
-	// Comment character without preceding whitespace are ignored.
-	// With leading whitespace the Comment character becomes part of the
-	// field, even if TrimLeadingSpace is true.
-	// Comment must be a valid rune and must not be \r, \n,
-	// or the Unicode replacement character (0xFFFD).
-	// It must also not be equal to Comma.
-	Comment rune
-
-	// FieldsPerRecord is the number of expected fields per record.
-	// If FieldsPerRecord is positive, Read requires each record to
-	// have the given number of fields. If FieldsPerRecord is 0, Read sets it to
-	// the number of fields in the first record, so that future records must
-	// have the same field count. If FieldsPerRecord is negative, no check is
-	// made and records may have a variable number of fields.
-	FieldsPerRecord int
-
-	// If LazyQuotes is true, a quote may appear in an unquoted field and a
-	// non-doubled quote may appear in a quoted field.
-	LazyQuotes bool
-
-	// If TrimLeadingSpace is true, leading white space in a field is ignored.
-	// This is done even if the field delimiter, Comma, is white space.
-	TrimLeadingSpace bool
-
-	// ReuseRecord controls whether calls to Read may return a slice sharing
-	// the backing array of the previous call's returned slice for performance.
-	// By default, each call to Read returns newly allocated memory owned by the caller.
-	ReuseRecord bool
-
-	TrailingComma bool // Deprecated: No longer used.
-
-	r *bufio.Reader
-
-	// numLine is the current line being read in the CSV file.
-	numLine int
-
-	// rawBuffer is a line buffer only used by the readLine method.
-	rawBuffer []byte
-
-	// recordBuffer holds the unescaped fields, one after another.
-	// The fields can be accessed by using the indexes in fieldIndexes.
-	// E.g., For the row `a,"b","c""d",e`, recordBuffer will contain `abc"de`
-	// and fieldIndexes will contain the indexes [1, 2, 5, 6].
-	recordBuffer []byte
-
-	// fieldIndexes is an index of fields inside recordBuffer.
-	// The i'th field ends at offset fieldIndexes[i] in recordBuffer.
-	fieldIndexes []int
-
-	// fieldPositions is an index of field positions for the
-	// last record returned by Read.
-	fieldPositions []position
-
-	// lastRecord is a record cache and only used when ReuseRecord == true.
-	lastRecord []string
-}
-
-// NewReader returns a new Reader that reads from r.
-func NewReader(r io.Reader) *Reader {
-	return &Reader{
-		Comma: ',',
-		r:     bufio.NewReader(r),
-	}
-}
-
-// Read reads one record (a slice of fields) from r.
-// If the record has an unexpected number of fields,
-// Read returns the record along with the error ErrFieldCount.
-// Except for that case, Read always returns either a non-nil
-// record or a non-nil error, but not both.
-// If there is no data left to be read, Read returns nil, io.EOF.
-// If ReuseRecord is true, the returned slice may be shared
-// between multiple calls to Read.
-func (r *Reader) Read() (record []string, err error) {
-	if r.ReuseRecord {
-		record, err = r.readRecord(r.lastRecord)
-		r.lastRecord = record
-	} else {
-		record, err = r.readRecord(nil)
-	}
-	return record, err
-}
-
-// FieldPos returns the line and column corresponding to
-// the start of the field with the given index in the slice most recently
-// returned by Read. Numbering of lines and columns starts at 1;
-// columns are counted in bytes, not runes.
-//
-// If this is called with an out-of-bounds index, it panics.
-func (r *Reader) FieldPos(field int) (line, column int) {
-	if field < 0 || field >= len(r.fieldPositions) {
-		panic("out of range index passed to FieldPos")
-	}
-	p := &r.fieldPositions[field]
-	return p.line, p.col
-}
-
-// pos holds the position of a field in the current line.
-type position struct {
-	line, col int
-}
-
-// ReadAll reads all the remaining records from r.
-// Each record is a slice of fields.
-// A successful call returns err == nil, not err == io.EOF. Because ReadAll is
-// defined to read until EOF, it does not treat end of file as an error to be
-// reported.
-func (r *Reader) ReadAll() (records [][]string, err error) {
-	for {
-		record, err := r.readRecord(nil)
-		if err == io.EOF {
-			return records, nil
-		}
-		if err != nil {
-			return nil, err
-		}
-		records = append(records, record)
-	}
-}
-
-// readLine reads the next line (with the trailing endline).
-// If EOF is hit without a trailing endline, it will be omitted.
-// If some bytes were read, then the error is never io.EOF.
-// The result is only valid until the next call to readLine.
-func (r *Reader) readLine() ([]byte, error) {
-	line, err := r.r.ReadSlice('\n')
-	if err == bufio.ErrBufferFull {
-		r.rawBuffer = append(r.rawBuffer[:0], line...)
-		for err == bufio.ErrBufferFull {
-			line, err = r.r.ReadSlice('\n')
-			r.rawBuffer = append(r.rawBuffer, line...)
-		}
-		line = r.rawBuffer
-	}
-	if len(line) > 0 && err == io.EOF {
-		err = nil
-		// For backwards compatibility, drop trailing \r before EOF.
-		if line[len(line)-1] == '\r' {
-			line = line[:len(line)-1]
-		}
-	}
-	r.numLine++
-	// Normalize \r\n to \n on all input lines.
-	if n := len(line); n >= 2 && line[n-2] == '\r' && line[n-1] == '\n' {
-		line[n-2] = '\n'
-		line = line[:n-1]
-	}
-	return line, err
-}
-
-// lengthNL reports the number of bytes for the trailing \n.
-func lengthNL(b []byte) int {
-	if len(b) > 0 && b[len(b)-1] == '\n' {
-		return 1
-	}
-	return 0
-}
-
-// nextRune returns the next rune in b or utf8.RuneError.
-func nextRune(b []byte) rune {
-	r, _ := utf8.DecodeRune(b)
-	return r
-}
-
-func (r *Reader) readRecord(dst []string) ([]string, error) {
-	if r.Comma == r.Comment || !validDelim(r.Comma) || (r.Comment != 0 && !validDelim(r.Comment)) {
-		return nil, errInvalidDelim
-	}
-
-	// Read line (automatically skipping past empty lines and any comments).
-	var line []byte
-	var errRead error
-	for errRead == nil {
-		line, errRead = r.readLine()
-		if r.Comment != 0 && nextRune(line) == r.Comment {
-			line = nil
-			continue // Skip comment lines
-		}
-		if errRead == nil && len(line) == lengthNL(line) {
-			line = nil
-			continue // Skip empty lines
-		}
-		break
-	}
-	if errRead == io.EOF {
-		return nil, errRead
-	}
-
-	// Parse each field in the record.
-	var err error
-	const quoteLen = len(`"`)
-	commaLen := utf8.RuneLen(r.Comma)
-	recLine := r.numLine // Starting line for record
-	r.recordBuffer = r.recordBuffer[:0]
-	r.fieldIndexes = r.fieldIndexes[:0]
-	r.fieldPositions = r.fieldPositions[:0]
-	pos := position{line: r.numLine, col: 1}
-parseField:
-	for {
-		if r.TrimLeadingSpace {
-			i := bytes.IndexFunc(line, func(r rune) bool {
-				return !unicode.IsSpace(r)
-			})
-			if i < 0 {
-				i = len(line)
-				pos.col -= lengthNL(line)
-			}
-			line = line[i:]
-			pos.col += i
-		}
-		if len(line) == 0 || line[0] != '"' {
-			// Non-quoted string field
-			i := bytes.IndexRune(line, r.Comma)
-			field := line
-			if i >= 0 {
-				field = field[:i]
-			} else {
-				field = field[:len(field)-lengthNL(field)]
-			}
-			// Check to make sure a quote does not appear in field.
-			if !r.LazyQuotes {
-				if j := bytes.IndexByte(field, '"'); j >= 0 {
-					col := pos.col + j
-					err = &ParseError{StartLine: recLine, Line: r.numLine, Column: col, Err: ErrBareQuote}
-					break parseField
-				}
-			}
-			r.recordBuffer = append(r.recordBuffer, field...)
-			r.fieldIndexes = append(r.fieldIndexes, len(r.recordBuffer))
-			r.fieldPositions = append(r.fieldPositions, pos)
-			if i >= 0 {
-				line = line[i+commaLen:]
-				pos.col += i + commaLen
-				continue parseField
-			}
-			break parseField
-		} else {
-			// Quoted string field
-			fieldPos := pos
-			line = line[quoteLen:]
-			pos.col += quoteLen
-			for {
-				i := bytes.IndexByte(line, '"')
-				if i >= 0 {
-					// Hit next quote.
-					r.recordBuffer = append(r.recordBuffer, line[:i]...)
-					line = line[i+quoteLen:]
-					pos.col += i + quoteLen
-					switch rn := nextRune(line); {
-					case rn == '"':
-						// `""` sequence (append quote).
-						r.recordBuffer = append(r.recordBuffer, '"')
-						line = line[quoteLen:]
-						pos.col += quoteLen
-					case rn == r.Comma:
-						// `",` sequence (end of field).
-						line = line[commaLen:]
-						pos.col += commaLen
-						r.fieldIndexes = append(r.fieldIndexes, len(r.recordBuffer))
-						r.fieldPositions = append(r.fieldPositions, fieldPos)
-						continue parseField
-					case lengthNL(line) == len(line):
-						// `"\n` sequence (end of line).
-						r.fieldIndexes = append(r.fieldIndexes, len(r.recordBuffer))
-						r.fieldPositions = append(r.fieldPositions, fieldPos)
-						break parseField
-					case r.LazyQuotes:
-						// `"` sequence (bare quote).
-						r.recordBuffer = append(r.recordBuffer, '"')
-					default:
-						// `"*` sequence (invalid non-escaped quote).
-						err = &ParseError{StartLine: recLine, Line: r.numLine, Column: pos.col - quoteLen, Err: ErrQuote}
-						break parseField
-					}
-				} else if len(line) > 0 {
-					// Hit end of line (copy all data so far).
-					r.recordBuffer = append(r.recordBuffer, line...)
-					if errRead != nil {
-						break parseField
-					}
-					pos.col += len(line)
-					line, errRead = r.readLine()
-					if len(line) > 0 {
-						pos.line++
-						pos.col = 1
-					}
-					if errRead == io.EOF {
-						errRead = nil
-					}
-				} else {
-					// Abrupt end of file (EOF or error).
-					if !r.LazyQuotes && errRead == nil {
-						err = &ParseError{StartLine: recLine, Line: pos.line, Column: pos.col, Err: ErrQuote}
-						break parseField
-					}
-					r.fieldIndexes = append(r.fieldIndexes, len(r.recordBuffer))
-					r.fieldPositions = append(r.fieldPositions, fieldPos)
-					break parseField
-				}
-			}
-		}
-	}
-	if err == nil {
-		err = errRead
-	}
-
-	// Create a single string and create slices out of it.
-	// This pins the memory of the fields together, but allocates once.
-	str := string(r.recordBuffer) // Convert to string once to batch allocations
-	dst = dst[:0]
-	if cap(dst) < len(r.fieldIndexes) {
-		dst = make([]string, len(r.fieldIndexes))
-	}
-	dst = dst[:len(r.fieldIndexes)]
-	var preIdx int
-	for i, idx := range r.fieldIndexes {
-		dst[i] = str[preIdx:idx]
-		preIdx = idx
-	}
-
-	// Check or update the expected fields per record.
-	if r.FieldsPerRecord > 0 {
-		if len(dst) != r.FieldsPerRecord && err == nil {
-			err = &ParseError{
-				StartLine: recLine,
-				Line:      recLine,
-				Column:    1,
-				Err:       ErrFieldCount,
-			}
-		}
-	} else if r.FieldsPerRecord == 0 {
-		r.FieldsPerRecord = len(dst)
-	}
-	return dst, err
-}
diff --git a/contrib/go/_std_1.18/src/encoding/hex/hex.go b/contrib/go/_std_1.18/src/encoding/hex/hex.go
deleted file mode 100644
index fbba78ffd2..0000000000
--- a/contrib/go/_std_1.18/src/encoding/hex/hex.go
+++ /dev/null
@@ -1,326 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package hex implements hexadecimal encoding and decoding.
-package hex
-
-import (
-	"errors"
-	"fmt"
-	"io"
-	"strings"
-)
-
-const hextable = "0123456789abcdef"
-
-// EncodedLen returns the length of an encoding of n source bytes.
-// Specifically, it returns n * 2.
-func EncodedLen(n int) int { return n * 2 }
-
-// Encode encodes src into EncodedLen(len(src))
-// bytes of dst. As a convenience, it returns the number
-// of bytes written to dst, but this value is always EncodedLen(len(src)).
-// Encode implements hexadecimal encoding.
-func Encode(dst, src []byte) int {
-	j := 0
-	for _, v := range src {
-		dst[j] = hextable[v>>4]
-		dst[j+1] = hextable[v&0x0f]
-		j += 2
-	}
-	return len(src) * 2
-}
-
-// ErrLength reports an attempt to decode an odd-length input
-// using Decode or DecodeString.
-// The stream-based Decoder returns io.ErrUnexpectedEOF instead of ErrLength.
-var ErrLength = errors.New("encoding/hex: odd length hex string")
-
-// InvalidByteError values describe errors resulting from an invalid byte in a hex string.
-type InvalidByteError byte
-
-func (e InvalidByteError) Error() string {
-	return fmt.Sprintf("encoding/hex: invalid byte: %#U", rune(e))
-}
-
-// DecodedLen returns the length of a decoding of x source bytes.
-// Specifically, it returns x / 2.
-func DecodedLen(x int) int { return x / 2 }
-
-// Decode decodes src into DecodedLen(len(src)) bytes,
-// returning the actual number of bytes written to dst.
-//
-// Decode expects that src contains only hexadecimal
-// characters and that src has even length.
-// If the input is malformed, Decode returns the number
-// of bytes decoded before the error.
-func Decode(dst, src []byte) (int, error) {
-	i, j := 0, 1
-	for ; j < len(src); j += 2 {
-		a, ok := fromHexChar(src[j-1])
-		if !ok {
-			return i, InvalidByteError(src[j-1])
-		}
-		b, ok := fromHexChar(src[j])
-		if !ok {
-			return i, InvalidByteError(src[j])
-		}
-		dst[i] = (a << 4) | b
-		i++
-	}
-	if len(src)%2 == 1 {
-		// Check for invalid char before reporting bad length,
-		// since the invalid char (if present) is an earlier problem.
-		if _, ok := fromHexChar(src[j-1]); !ok {
-			return i, InvalidByteError(src[j-1])
-		}
-		return i, ErrLength
-	}
-	return i, nil
-}
-
-// fromHexChar converts a hex character into its value and a success flag.
-func fromHexChar(c byte) (byte, bool) {
-	switch {
-	case '0' <= c && c <= '9':
-		return c - '0', true
-	case 'a' <= c && c <= 'f':
-		return c - 'a' + 10, true
-	case 'A' <= c && c <= 'F':
-		return c - 'A' + 10, true
-	}
-
-	return 0, false
-}
-
-// EncodeToString returns the hexadecimal encoding of src.
-func EncodeToString(src []byte) string {
-	dst := make([]byte, EncodedLen(len(src)))
-	Encode(dst, src)
-	return string(dst)
-}
-
-// DecodeString returns the bytes represented by the hexadecimal string s.
-//
-// DecodeString expects that src contains only hexadecimal
-// characters and that src has even length.
-// If the input is malformed, DecodeString returns
-// the bytes decoded before the error.
-func DecodeString(s string) ([]byte, error) {
-	src := []byte(s)
-	// We can use the source slice itself as the destination
-	// because the decode loop increments by one and then the 'seen' byte is not used anymore.
-	n, err := Decode(src, src)
-	return src[:n], err
-}
-
-// Dump returns a string that contains a hex dump of the given data. The format
-// of the hex dump matches the output of `hexdump -C` on the command line.
-func Dump(data []byte) string {
-	if len(data) == 0 {
-		return ""
-	}
-
-	var buf strings.Builder
-	// Dumper will write 79 bytes per complete 16 byte chunk, and at least
-	// 64 bytes for whatever remains. Round the allocation up, since only a
-	// maximum of 15 bytes will be wasted.
-	buf.Grow((1 + ((len(data) - 1) / 16)) * 79)
-
-	dumper := Dumper(&buf)
-	dumper.Write(data)
-	dumper.Close()
-	return buf.String()
-}
-
-// bufferSize is the number of hexadecimal characters to buffer in encoder and decoder.
-const bufferSize = 1024
-
-type encoder struct {
-	w   io.Writer
-	err error
-	out [bufferSize]byte // output buffer
-}
-
-// NewEncoder returns an io.Writer that writes lowercase hexadecimal characters to w.
-func NewEncoder(w io.Writer) io.Writer {
-	return &encoder{w: w}
-}
-
-func (e *encoder) Write(p []byte) (n int, err error) {
-	for len(p) > 0 && e.err == nil {
-		chunkSize := bufferSize / 2
-		if len(p) < chunkSize {
-			chunkSize = len(p)
-		}
-
-		var written int
-		encoded := Encode(e.out[:], p[:chunkSize])
-		written, e.err = e.w.Write(e.out[:encoded])
-		n += written / 2
-		p = p[chunkSize:]
-	}
-	return n, e.err
-}
-
-type decoder struct {
-	r   io.Reader
-	err error
-	in  []byte           // input buffer (encoded form)
-	arr [bufferSize]byte // backing array for in
-}
-
-// NewDecoder returns an io.Reader that decodes hexadecimal characters from r.
-// NewDecoder expects that r contain only an even number of hexadecimal characters.
-func NewDecoder(r io.Reader) io.Reader {
-	return &decoder{r: r}
-}
-
-func (d *decoder) Read(p []byte) (n int, err error) {
-	// Fill internal buffer with sufficient bytes to decode
-	if len(d.in) < 2 && d.err == nil {
-		var numCopy, numRead int
-		numCopy = copy(d.arr[:], d.in) // Copies either 0 or 1 bytes
-		numRead, d.err = d.r.Read(d.arr[numCopy:])
-		d.in = d.arr[:numCopy+numRead]
-		if d.err == io.EOF && len(d.in)%2 != 0 {
-			if _, ok := fromHexChar(d.in[len(d.in)-1]); !ok {
-				d.err = InvalidByteError(d.in[len(d.in)-1])
-			} else {
-				d.err = io.ErrUnexpectedEOF
-			}
-		}
-	}
-
-	// Decode internal buffer into output buffer
-	if numAvail := len(d.in) / 2; len(p) > numAvail {
-		p = p[:numAvail]
-	}
-	numDec, err := Decode(p, d.in[:len(p)*2])
-	d.in = d.in[2*numDec:]
-	if err != nil {
-		d.in, d.err = nil, err // Decode error; discard input remainder
-	}
-
-	if len(d.in) < 2 {
-		return numDec, d.err // Only expose errors when buffer fully consumed
-	}
-	return numDec, nil
-}
-
-// Dumper returns a WriteCloser that writes a hex dump of all written data to
-// w. The format of the dump matches the output of `hexdump -C` on the command
-// line.
-func Dumper(w io.Writer) io.WriteCloser {
-	return &dumper{w: w}
-}
-
-type dumper struct {
-	w          io.Writer
-	rightChars [18]byte
-	buf        [14]byte
-	used       int  // number of bytes in the current line
-	n          uint // number of bytes, total
-	closed     bool
-}
-
-func toChar(b byte) byte {
-	if b < 32 || b > 126 {
-		return '.'
-	}
-	return b
-}
-
-func (h *dumper) Write(data []byte) (n int, err error) {
-	if h.closed {
-		return 0, errors.New("encoding/hex: dumper closed")
-	}
-
-	// Output lines look like:
-	// 00000010  2e 2f 30 31 32 33 34 35  36 37 38 39 3a 3b 3c 3d  |./0123456789:;<=|
-	// ^ offset                          ^ extra space              ^ ASCII of line.
-	for i := range data {
-		if h.used == 0 {
-			// At the beginning of a line we print the current
-			// offset in hex.
-			h.buf[0] = byte(h.n >> 24)
-			h.buf[1] = byte(h.n >> 16)
-			h.buf[2] = byte(h.n >> 8)
-			h.buf[3] = byte(h.n)
-			Encode(h.buf[4:], h.buf[:4])
-			h.buf[12] = ' '
-			h.buf[13] = ' '
-			_, err = h.w.Write(h.buf[4:])
-			if err != nil {
-				return
-			}
-		}
-		Encode(h.buf[:], data[i:i+1])
-		h.buf[2] = ' '
-		l := 3
-		if h.used == 7 {
-			// There's an additional space after the 8th byte.
-			h.buf[3] = ' '
-			l = 4
-		} else if h.used == 15 {
-			// At the end of the line there's an extra space and
-			// the bar for the right column.
-			h.buf[3] = ' '
-			h.buf[4] = '|'
-			l = 5
-		}
-		_, err = h.w.Write(h.buf[:l])
-		if err != nil {
-			return
-		}
-		n++
-		h.rightChars[h.used] = toChar(data[i])
-		h.used++
-		h.n++
-		if h.used == 16 {
-			h.rightChars[16] = '|'
-			h.rightChars[17] = '\n'
-			_, err = h.w.Write(h.rightChars[:])
-			if err != nil {
-				return
-			}
-			h.used = 0
-		}
-	}
-	return
-}
-
-func (h *dumper) Close() (err error) {
-	// See the comments in Write() for the details of this format.
-	if h.closed {
-		return
-	}
-	h.closed = true
-	if h.used == 0 {
-		return
-	}
-	h.buf[0] = ' '
-	h.buf[1] = ' '
-	h.buf[2] = ' '
-	h.buf[3] = ' '
-	h.buf[4] = '|'
-	nBytes := h.used
-	for h.used < 16 {
-		l := 3
-		if h.used == 7 {
-			l = 4
-		} else if h.used == 15 {
-			l = 5
-		}
-		_, err = h.w.Write(h.buf[:l])
-		if err != nil {
-			return
-		}
-		h.used++
-	}
-	h.rightChars[nBytes] = '|'
-	h.rightChars[nBytes+1] = '\n'
-	_, err = h.w.Write(h.rightChars[:nBytes+2])
-	return
-}
diff --git a/contrib/go/_std_1.18/src/encoding/pem/pem.go b/contrib/go/_std_1.18/src/encoding/pem/pem.go
deleted file mode 100644
index 743876c906..0000000000
--- a/contrib/go/_std_1.18/src/encoding/pem/pem.go
+++ /dev/null
@@ -1,314 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package pem implements the PEM data encoding, which originated in Privacy
-// Enhanced Mail. The most common use of PEM encoding today is in TLS keys and
-// certificates. See RFC 1421.
-package pem
-
-import (
-	"bytes"
-	"encoding/base64"
-	"errors"
-	"io"
-	"sort"
-	"strings"
-)
-
-// A Block represents a PEM encoded structure.
-//
-// The encoded form is:
-//    -----BEGIN Type-----
-//    Headers
-//    base64-encoded Bytes
-//    -----END Type-----
-// where Headers is a possibly empty sequence of Key: Value lines.
-type Block struct {
-	Type    string            // The type, taken from the preamble (i.e. "RSA PRIVATE KEY").
-	Headers map[string]string // Optional headers.
-	Bytes   []byte            // The decoded bytes of the contents. Typically a DER encoded ASN.1 structure.
-}
-
-// getLine results the first \r\n or \n delineated line from the given byte
-// array. The line does not include trailing whitespace or the trailing new
-// line bytes. The remainder of the byte array (also not including the new line
-// bytes) is also returned and this will always be smaller than the original
-// argument.
-func getLine(data []byte) (line, rest []byte) {
-	i := bytes.IndexByte(data, '\n')
-	var j int
-	if i < 0 {
-		i = len(data)
-		j = i
-	} else {
-		j = i + 1
-		if i > 0 && data[i-1] == '\r' {
-			i--
-		}
-	}
-	return bytes.TrimRight(data[0:i], " \t"), data[j:]
-}
-
-// removeSpacesAndTabs returns a copy of its input with all spaces and tabs
-// removed, if there were any. Otherwise, the input is returned unchanged.
-//
-// The base64 decoder already skips newline characters, so we don't need to
-// filter them out here.
-func removeSpacesAndTabs(data []byte) []byte {
-	if !bytes.ContainsAny(data, " \t") {
-		// Fast path; most base64 data within PEM contains newlines, but
-		// no spaces nor tabs. Skip the extra alloc and work.
-		return data
-	}
-	result := make([]byte, len(data))
-	n := 0
-
-	for _, b := range data {
-		if b == ' ' || b == '\t' {
-			continue
-		}
-		result[n] = b
-		n++
-	}
-
-	return result[0:n]
-}
-
-var pemStart = []byte("\n-----BEGIN ")
-var pemEnd = []byte("\n-----END ")
-var pemEndOfLine = []byte("-----")
-var colon = []byte(":")
-
-// Decode will find the next PEM formatted block (certificate, private key
-// etc) in the input. It returns that block and the remainder of the input. If
-// no PEM data is found, p is nil and the whole of the input is returned in
-// rest.
-func Decode(data []byte) (p *Block, rest []byte) {
-	// pemStart begins with a newline. However, at the very beginning of
-	// the byte array, we'll accept the start string without it.
-	rest = data
-	for {
-		if bytes.HasPrefix(rest, pemStart[1:]) {
-			rest = rest[len(pemStart)-1:]
-		} else if _, after, ok := bytes.Cut(rest, pemStart); ok {
-			rest = after
-		} else {
-			return nil, data
-		}
-
-		var typeLine []byte
-		typeLine, rest = getLine(rest)
-		if !bytes.HasSuffix(typeLine, pemEndOfLine) {
-			continue
-		}
-		typeLine = typeLine[0 : len(typeLine)-len(pemEndOfLine)]
-
-		p = &Block{
-			Headers: make(map[string]string),
-			Type:    string(typeLine),
-		}
-
-		for {
-			// This loop terminates because getLine's second result is
-			// always smaller than its argument.
-			if len(rest) == 0 {
-				return nil, data
-			}
-			line, next := getLine(rest)
-
-			key, val, ok := bytes.Cut(line, colon)
-			if !ok {
-				break
-			}
-
-			// TODO(agl): need to cope with values that spread across lines.
-			key = bytes.TrimSpace(key)
-			val = bytes.TrimSpace(val)
-			p.Headers[string(key)] = string(val)
-			rest = next
-		}
-
-		var endIndex, endTrailerIndex int
-
-		// If there were no headers, the END line might occur
-		// immediately, without a leading newline.
-		if len(p.Headers) == 0 && bytes.HasPrefix(rest, pemEnd[1:]) {
-			endIndex = 0
-			endTrailerIndex = len(pemEnd) - 1
-		} else {
-			endIndex = bytes.Index(rest, pemEnd)
-			endTrailerIndex = endIndex + len(pemEnd)
-		}
-
-		if endIndex < 0 {
-			continue
-		}
-
-		// After the "-----" of the ending line, there should be the same type
-		// and then a final five dashes.
-		endTrailer := rest[endTrailerIndex:]
-		endTrailerLen := len(typeLine) + len(pemEndOfLine)
-		if len(endTrailer) < endTrailerLen {
-			continue
-		}
-
-		restOfEndLine := endTrailer[endTrailerLen:]
-		endTrailer = endTrailer[:endTrailerLen]
-		if !bytes.HasPrefix(endTrailer, typeLine) ||
-			!bytes.HasSuffix(endTrailer, pemEndOfLine) {
-			continue
-		}
-
-		// The line must end with only whitespace.
-		if s, _ := getLine(restOfEndLine); len(s) != 0 {
-			continue
-		}
-
-		base64Data := removeSpacesAndTabs(rest[:endIndex])
-		p.Bytes = make([]byte, base64.StdEncoding.DecodedLen(len(base64Data)))
-		n, err := base64.StdEncoding.Decode(p.Bytes, base64Data)
-		if err != nil {
-			continue
-		}
-		p.Bytes = p.Bytes[:n]
-
-		// the -1 is because we might have only matched pemEnd without the
-		// leading newline if the PEM block was empty.
-		_, rest = getLine(rest[endIndex+len(pemEnd)-1:])
-		return p, rest
-	}
-}
-
-const pemLineLength = 64
-
-type lineBreaker struct {
-	line [pemLineLength]byte
-	used int
-	out  io.Writer
-}
-
-var nl = []byte{'\n'}
-
-func (l *lineBreaker) Write(b []byte) (n int, err error) {
-	if l.used+len(b) < pemLineLength {
-		copy(l.line[l.used:], b)
-		l.used += len(b)
-		return len(b), nil
-	}
-
-	n, err = l.out.Write(l.line[0:l.used])
-	if err != nil {
-		return
-	}
-	excess := pemLineLength - l.used
-	l.used = 0
-
-	n, err = l.out.Write(b[0:excess])
-	if err != nil {
-		return
-	}
-
-	n, err = l.out.Write(nl)
-	if err != nil {
-		return
-	}
-
-	return l.Write(b[excess:])
-}
-
-func (l *lineBreaker) Close() (err error) {
-	if l.used > 0 {
-		_, err = l.out.Write(l.line[0:l.used])
-		if err != nil {
-			return
-		}
-		_, err = l.out.Write(nl)
-	}
-
-	return
-}
-
-func writeHeader(out io.Writer, k, v string) error {
-	_, err := out.Write([]byte(k + ": " + v + "\n"))
-	return err
-}
-
-// Encode writes the PEM encoding of b to out.
-func Encode(out io.Writer, b *Block) error {
-	// Check for invalid block before writing any output.
-	for k := range b.Headers {
-		if strings.Contains(k, ":") {
-			return errors.New("pem: cannot encode a header key that contains a colon")
-		}
-	}
-
-	// All errors below are relayed from underlying io.Writer,
-	// so it is now safe to write data.
-
-	if _, err := out.Write(pemStart[1:]); err != nil {
-		return err
-	}
-	if _, err := out.Write([]byte(b.Type + "-----\n")); err != nil {
-		return err
-	}
-
-	if len(b.Headers) > 0 {
-		const procType = "Proc-Type"
-		h := make([]string, 0, len(b.Headers))
-		hasProcType := false
-		for k := range b.Headers {
-			if k == procType {
-				hasProcType = true
-				continue
-			}
-			h = append(h, k)
-		}
-		// The Proc-Type header must be written first.
-		// See RFC 1421, section 4.6.1.1
-		if hasProcType {
-			if err := writeHeader(out, procType, b.Headers[procType]); err != nil {
-				return err
-			}
-		}
-		// For consistency of output, write other headers sorted by key.
-		sort.Strings(h)
-		for _, k := range h {
-			if err := writeHeader(out, k, b.Headers[k]); err != nil {
-				return err
-			}
-		}
-		if _, err := out.Write(nl); err != nil {
-			return err
-		}
-	}
-
-	var breaker lineBreaker
-	breaker.out = out
-
-	b64 := base64.NewEncoder(base64.StdEncoding, &breaker)
-	if _, err := b64.Write(b.Bytes); err != nil {
-		return err
-	}
-	b64.Close()
-	breaker.Close()
-
-	if _, err := out.Write(pemEnd[1:]); err != nil {
-		return err
-	}
-	_, err := out.Write([]byte(b.Type + "-----\n"))
-	return err
-}
-
-// EncodeToMemory returns the PEM encoding of b.
-//
-// If b has invalid headers and cannot be encoded,
-// EncodeToMemory returns nil. If it is important to
-// report details about this error case, use Encode instead.
-func EncodeToMemory(b *Block) []byte {
-	var buf bytes.Buffer
-	if err := Encode(&buf, b); err != nil {
-		return nil
-	}
-	return buf.Bytes()
-}
diff --git a/contrib/go/_std_1.18/src/flag/flag.go b/contrib/go/_std_1.18/src/flag/flag.go
deleted file mode 100644
index 4e2af450c5..0000000000
--- a/contrib/go/_std_1.18/src/flag/flag.go
+++ /dev/null
@@ -1,1079 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-/*
-	Package flag implements command-line flag parsing.
-
-	Usage
-
-	Define flags using flag.String(), Bool(), Int(), etc.
-
-	This declares an integer flag, -n, stored in the pointer nFlag, with type *int:
-		import "flag"
-		var nFlag = flag.Int("n", 1234, "help message for flag n")
-	If you like, you can bind the flag to a variable using the Var() functions.
-		var flagvar int
-		func init() {
-			flag.IntVar(&flagvar, "flagname", 1234, "help message for flagname")
-		}
-	Or you can create custom flags that satisfy the Value interface (with
-	pointer receivers) and couple them to flag parsing by
-		flag.Var(&flagVal, "name", "help message for flagname")
-	For such flags, the default value is just the initial value of the variable.
-
-	After all flags are defined, call
-		flag.Parse()
-	to parse the command line into the defined flags.
-
-	Flags may then be used directly. If you're using the flags themselves,
-	they are all pointers; if you bind to variables, they're values.
-		fmt.Println("ip has value ", *ip)
-		fmt.Println("flagvar has value ", flagvar)
-
-	After parsing, the arguments following the flags are available as the
-	slice flag.Args() or individually as flag.Arg(i).
-	The arguments are indexed from 0 through flag.NArg()-1.
-
-	Command line flag syntax
-
-	The following forms are permitted:
-
-		-flag
-		-flag=x
-		-flag x  // non-boolean flags only
-	One or two minus signs may be used; they are equivalent.
-	The last form is not permitted for boolean flags because the
-	meaning of the command
-		cmd -x *
-	where * is a Unix shell wildcard, will change if there is a file
-	called 0, false, etc. You must use the -flag=false form to turn
-	off a boolean flag.
-
-	Flag parsing stops just before the first non-flag argument
-	("-" is a non-flag argument) or after the terminator "--".
-
-	Integer flags accept 1234, 0664, 0x1234 and may be negative.
-	Boolean flags may be:
-		1, 0, t, f, T, F, true, false, TRUE, FALSE, True, False
-	Duration flags accept any input valid for time.ParseDuration.
-
-	The default set of command-line flags is controlled by
-	top-level functions.  The FlagSet type allows one to define
-	independent sets of flags, such as to implement subcommands
-	in a command-line interface. The methods of FlagSet are
-	analogous to the top-level functions for the command-line
-	flag set.
-*/
-package flag
-
-import (
-	"errors"
-	"fmt"
-	"io"
-	"os"
-	"reflect"
-	"sort"
-	"strconv"
-	"strings"
-	"time"
-)
-
-// ErrHelp is the error returned if the -help or -h flag is invoked
-// but no such flag is defined.
-var ErrHelp = errors.New("flag: help requested")
-
-// errParse is returned by Set if a flag's value fails to parse, such as with an invalid integer for Int.
-// It then gets wrapped through failf to provide more information.
-var errParse = errors.New("parse error")
-
-// errRange is returned by Set if a flag's value is out of range.
-// It then gets wrapped through failf to provide more information.
-var errRange = errors.New("value out of range")
-
-func numError(err error) error {
-	ne, ok := err.(*strconv.NumError)
-	if !ok {
-		return err
-	}
-	if ne.Err == strconv.ErrSyntax {
-		return errParse
-	}
-	if ne.Err == strconv.ErrRange {
-		return errRange
-	}
-	return err
-}
-
-// -- bool Value
-type boolValue bool
-
-func newBoolValue(val bool, p *bool) *boolValue {
-	*p = val
-	return (*boolValue)(p)
-}
-
-func (b *boolValue) Set(s string) error {
-	v, err := strconv.ParseBool(s)
-	if err != nil {
-		err = errParse
-	}
-	*b = boolValue(v)
-	return err
-}
-
-func (b *boolValue) Get() any { return bool(*b) }
-
-func (b *boolValue) String() string { return strconv.FormatBool(bool(*b)) }
-
-func (b *boolValue) IsBoolFlag() bool { return true }
-
-// optional interface to indicate boolean flags that can be
-// supplied without "=value" text
-type boolFlag interface {
-	Value
-	IsBoolFlag() bool
-}
-
-// -- int Value
-type intValue int
-
-func newIntValue(val int, p *int) *intValue {
-	*p = val
-	return (*intValue)(p)
-}
-
-func (i *intValue) Set(s string) error {
-	v, err := strconv.ParseInt(s, 0, strconv.IntSize)
-	if err != nil {
-		err = numError(err)
-	}
-	*i = intValue(v)
-	return err
-}
-
-func (i *intValue) Get() any { return int(*i) }
-
-func (i *intValue) String() string { return strconv.Itoa(int(*i)) }
-
-// -- int64 Value
-type int64Value int64
-
-func newInt64Value(val int64, p *int64) *int64Value {
-	*p = val
-	return (*int64Value)(p)
-}
-
-func (i *int64Value) Set(s string) error {
-	v, err := strconv.ParseInt(s, 0, 64)
-	if err != nil {
-		err = numError(err)
-	}
-	*i = int64Value(v)
-	return err
-}
-
-func (i *int64Value) Get() any { return int64(*i) }
-
-func (i *int64Value) String() string { return strconv.FormatInt(int64(*i), 10) }
-
-// -- uint Value
-type uintValue uint
-
-func newUintValue(val uint, p *uint) *uintValue {
-	*p = val
-	return (*uintValue)(p)
-}
-
-func (i *uintValue) Set(s string) error {
-	v, err := strconv.ParseUint(s, 0, strconv.IntSize)
-	if err != nil {
-		err = numError(err)
-	}
-	*i = uintValue(v)
-	return err
-}
-
-func (i *uintValue) Get() any { return uint(*i) }
-
-func (i *uintValue) String() string { return strconv.FormatUint(uint64(*i), 10) }
-
-// -- uint64 Value
-type uint64Value uint64
-
-func newUint64Value(val uint64, p *uint64) *uint64Value {
-	*p = val
-	return (*uint64Value)(p)
-}
-
-func (i *uint64Value) Set(s string) error {
-	v, err := strconv.ParseUint(s, 0, 64)
-	if err != nil {
-		err = numError(err)
-	}
-	*i = uint64Value(v)
-	return err
-}
-
-func (i *uint64Value) Get() any { return uint64(*i) }
-
-func (i *uint64Value) String() string { return strconv.FormatUint(uint64(*i), 10) }
-
-// -- string Value
-type stringValue string
-
-func newStringValue(val string, p *string) *stringValue {
-	*p = val
-	return (*stringValue)(p)
-}
-
-func (s *stringValue) Set(val string) error {
-	*s = stringValue(val)
-	return nil
-}
-
-func (s *stringValue) Get() any { return string(*s) }
-
-func (s *stringValue) String() string { return string(*s) }
-
-// -- float64 Value
-type float64Value float64
-
-func newFloat64Value(val float64, p *float64) *float64Value {
-	*p = val
-	return (*float64Value)(p)
-}
-
-func (f *float64Value) Set(s string) error {
-	v, err := strconv.ParseFloat(s, 64)
-	if err != nil {
-		err = numError(err)
-	}
-	*f = float64Value(v)
-	return err
-}
-
-func (f *float64Value) Get() any { return float64(*f) }
-
-func (f *float64Value) String() string { return strconv.FormatFloat(float64(*f), 'g', -1, 64) }
-
-// -- time.Duration Value
-type durationValue time.Duration
-
-func newDurationValue(val time.Duration, p *time.Duration) *durationValue {
-	*p = val
-	return (*durationValue)(p)
-}
-
-func (d *durationValue) Set(s string) error {
-	v, err := time.ParseDuration(s)
-	if err != nil {
-		err = errParse
-	}
-	*d = durationValue(v)
-	return err
-}
-
-func (d *durationValue) Get() any { return time.Duration(*d) }
-
-func (d *durationValue) String() string { return (*time.Duration)(d).String() }
-
-type funcValue func(string) error
-
-func (f funcValue) Set(s string) error { return f(s) }
-
-func (f funcValue) String() string { return "" }
-
-// Value is the interface to the dynamic value stored in a flag.
-// (The default value is represented as a string.)
-//
-// If a Value has an IsBoolFlag() bool method returning true,
-// the command-line parser makes -name equivalent to -name=true
-// rather than using the next command-line argument.
-//
-// Set is called once, in command line order, for each flag present.
-// The flag package may call the String method with a zero-valued receiver,
-// such as a nil pointer.
-type Value interface {
-	String() string
-	Set(string) error
-}
-
-// Getter is an interface that allows the contents of a Value to be retrieved.
-// It wraps the Value interface, rather than being part of it, because it
-// appeared after Go 1 and its compatibility rules. All Value types provided
-// by this package satisfy the Getter interface, except the type used by Func.
-type Getter interface {
-	Value
-	Get() any
-}
-
-// ErrorHandling defines how FlagSet.Parse behaves if the parse fails.
-type ErrorHandling int
-
-// These constants cause FlagSet.Parse to behave as described if the parse fails.
-const (
-	ContinueOnError ErrorHandling = iota // Return a descriptive error.
-	ExitOnError                          // Call os.Exit(2) or for -h/-help Exit(0).
-	PanicOnError                         // Call panic with a descriptive error.
-)
-
-// A FlagSet represents a set of defined flags. The zero value of a FlagSet
-// has no name and has ContinueOnError error handling.
-//
-// Flag names must be unique within a FlagSet. An attempt to define a flag whose
-// name is already in use will cause a panic.
-type FlagSet struct {
-	// Usage is the function called when an error occurs while parsing flags.
-	// The field is a function (not a method) that may be changed to point to
-	// a custom error handler. What happens after Usage is called depends
-	// on the ErrorHandling setting; for the command line, this defaults
-	// to ExitOnError, which exits the program after calling Usage.
-	Usage func()
-
-	name          string
-	parsed        bool
-	actual        map[string]*Flag
-	formal        map[string]*Flag
-	args          []string // arguments after flags
-	errorHandling ErrorHandling
-	output        io.Writer // nil means stderr; use Output() accessor
-}
-
-// A Flag represents the state of a flag.
-type Flag struct {
-	Name     string // name as it appears on command line
-	Usage    string // help message
-	Value    Value  // value as set
-	DefValue string // default value (as text); for usage message
-}
-
-// sortFlags returns the flags as a slice in lexicographical sorted order.
-func sortFlags(flags map[string]*Flag) []*Flag {
-	result := make([]*Flag, len(flags))
-	i := 0
-	for _, f := range flags {
-		result[i] = f
-		i++
-	}
-	sort.Slice(result, func(i, j int) bool {
-		return result[i].Name < result[j].Name
-	})
-	return result
-}
-
-// Output returns the destination for usage and error messages. os.Stderr is returned if
-// output was not set or was set to nil.
-func (f *FlagSet) Output() io.Writer {
-	if f.output == nil {
-		return os.Stderr
-	}
-	return f.output
-}
-
-// Name returns the name of the flag set.
-func (f *FlagSet) Name() string {
-	return f.name
-}
-
-// ErrorHandling returns the error handling behavior of the flag set.
-func (f *FlagSet) ErrorHandling() ErrorHandling {
-	return f.errorHandling
-}
-
-// SetOutput sets the destination for usage and error messages.
-// If output is nil, os.Stderr is used.
-func (f *FlagSet) SetOutput(output io.Writer) {
-	f.output = output
-}
-
-// VisitAll visits the flags in lexicographical order, calling fn for each.
-// It visits all flags, even those not set.
-func (f *FlagSet) VisitAll(fn func(*Flag)) {
-	for _, flag := range sortFlags(f.formal) {
-		fn(flag)
-	}
-}
-
-// VisitAll visits the command-line flags in lexicographical order, calling
-// fn for each. It visits all flags, even those not set.
-func VisitAll(fn func(*Flag)) {
-	CommandLine.VisitAll(fn)
-}
-
-// Visit visits the flags in lexicographical order, calling fn for each.
-// It visits only those flags that have been set.
-func (f *FlagSet) Visit(fn func(*Flag)) {
-	for _, flag := range sortFlags(f.actual) {
-		fn(flag)
-	}
-}
-
-// Visit visits the command-line flags in lexicographical order, calling fn
-// for each. It visits only those flags that have been set.
-func Visit(fn func(*Flag)) {
-	CommandLine.Visit(fn)
-}
-
-// Lookup returns the Flag structure of the named flag, returning nil if none exists.
-func (f *FlagSet) Lookup(name string) *Flag {
-	return f.formal[name]
-}
-
-// Lookup returns the Flag structure of the named command-line flag,
-// returning nil if none exists.
-func Lookup(name string) *Flag {
-	return CommandLine.formal[name]
-}
-
-// Set sets the value of the named flag.
-func (f *FlagSet) Set(name, value string) error {
-	flag, ok := f.formal[name]
-	if !ok {
-		return fmt.Errorf("no such flag -%v", name)
-	}
-	err := flag.Value.Set(value)
-	if err != nil {
-		return err
-	}
-	if f.actual == nil {
-		f.actual = make(map[string]*Flag)
-	}
-	f.actual[name] = flag
-	return nil
-}
-
-// Set sets the value of the named command-line flag.
-func Set(name, value string) error {
-	return CommandLine.Set(name, value)
-}
-
-// isZeroValue determines whether the string represents the zero
-// value for a flag.
-func isZeroValue(flag *Flag, value string) bool {
-	// Build a zero value of the flag's Value type, and see if the
-	// result of calling its String method equals the value passed in.
-	// This works unless the Value type is itself an interface type.
-	typ := reflect.TypeOf(flag.Value)
-	var z reflect.Value
-	if typ.Kind() == reflect.Pointer {
-		z = reflect.New(typ.Elem())
-	} else {
-		z = reflect.Zero(typ)
-	}
-	return value == z.Interface().(Value).String()
-}
-
-// UnquoteUsage extracts a back-quoted name from the usage
-// string for a flag and returns it and the un-quoted usage.
-// Given "a `name` to show" it returns ("name", "a name to show").
-// If there are no back quotes, the name is an educated guess of the
-// type of the flag's value, or the empty string if the flag is boolean.
-func UnquoteUsage(flag *Flag) (name string, usage string) {
-	// Look for a back-quoted name, but avoid the strings package.
-	usage = flag.Usage
-	for i := 0; i < len(usage); i++ {
-		if usage[i] == '`' {
-			for j := i + 1; j < len(usage); j++ {
-				if usage[j] == '`' {
-					name = usage[i+1 : j]
-					usage = usage[:i] + name + usage[j+1:]
-					return name, usage
-				}
-			}
-			break // Only one back quote; use type name.
-		}
-	}
-	// No explicit name, so use type if we can find one.
-	name = "value"
-	switch flag.Value.(type) {
-	case boolFlag:
-		name = ""
-	case *durationValue:
-		name = "duration"
-	case *float64Value:
-		name = "float"
-	case *intValue, *int64Value:
-		name = "int"
-	case *stringValue:
-		name = "string"
-	case *uintValue, *uint64Value:
-		name = "uint"
-	}
-	return
-}
-
-// PrintDefaults prints, to standard error unless configured otherwise, the
-// default values of all defined command-line flags in the set. See the
-// documentation for the global function PrintDefaults for more information.
-func (f *FlagSet) PrintDefaults() {
-	f.VisitAll(func(flag *Flag) {
-		var b strings.Builder
-		fmt.Fprintf(&b, "  -%s", flag.Name) // Two spaces before -; see next two comments.
-		name, usage := UnquoteUsage(flag)
-		if len(name) > 0 {
-			b.WriteString(" ")
-			b.WriteString(name)
-		}
-		// Boolean flags of one ASCII letter are so common we
-		// treat them specially, putting their usage on the same line.
-		if b.Len() <= 4 { // space, space, '-', 'x'.
-			b.WriteString("\t")
-		} else {
-			// Four spaces before the tab triggers good alignment
-			// for both 4- and 8-space tab stops.
-			b.WriteString("\n    \t")
-		}
-		b.WriteString(strings.ReplaceAll(usage, "\n", "\n    \t"))
-
-		if !isZeroValue(flag, flag.DefValue) {
-			if _, ok := flag.Value.(*stringValue); ok {
-				// put quotes on the value
-				fmt.Fprintf(&b, " (default %q)", flag.DefValue)
-			} else {
-				fmt.Fprintf(&b, " (default %v)", flag.DefValue)
-			}
-		}
-		fmt.Fprint(f.Output(), b.String(), "\n")
-	})
-}
-
-// PrintDefaults prints, to standard error unless configured otherwise,
-// a usage message showing the default settings of all defined
-// command-line flags.
-// For an integer valued flag x, the default output has the form
-//	-x int
-//		usage-message-for-x (default 7)
-// The usage message will appear on a separate line for anything but
-// a bool flag with a one-byte name. For bool flags, the type is
-// omitted and if the flag name is one byte the usage message appears
-// on the same line. The parenthetical default is omitted if the
-// default is the zero value for the type. The listed type, here int,
-// can be changed by placing a back-quoted name in the flag's usage
-// string; the first such item in the message is taken to be a parameter
-// name to show in the message and the back quotes are stripped from
-// the message when displayed. For instance, given
-//	flag.String("I", "", "search `directory` for include files")
-// the output will be
-//	-I directory
-//		search directory for include files.
-//
-// To change the destination for flag messages, call CommandLine.SetOutput.
-func PrintDefaults() {
-	CommandLine.PrintDefaults()
-}
-
-// defaultUsage is the default function to print a usage message.
-func (f *FlagSet) defaultUsage() {
-	if f.name == "" {
-		fmt.Fprintf(f.Output(), "Usage:\n")
-	} else {
-		fmt.Fprintf(f.Output(), "Usage of %s:\n", f.name)
-	}
-	f.PrintDefaults()
-}
-
-// NOTE: Usage is not just defaultUsage(CommandLine)
-// because it serves (via godoc flag Usage) as the example
-// for how to write your own usage function.
-
-// Usage prints a usage message documenting all defined command-line flags
-// to CommandLine's output, which by default is os.Stderr.
-// It is called when an error occurs while parsing flags.
-// The function is a variable that may be changed to point to a custom function.
-// By default it prints a simple header and calls PrintDefaults; for details about the
-// format of the output and how to control it, see the documentation for PrintDefaults.
-// Custom usage functions may choose to exit the program; by default exiting
-// happens anyway as the command line's error handling strategy is set to
-// ExitOnError.
-var Usage = func() {
-	fmt.Fprintf(CommandLine.Output(), "Usage of %s:\n", os.Args[0])
-	PrintDefaults()
-}
-
-// NFlag returns the number of flags that have been set.
-func (f *FlagSet) NFlag() int { return len(f.actual) }
-
-// NFlag returns the number of command-line flags that have been set.
-func NFlag() int { return len(CommandLine.actual) }
-
-// Arg returns the i'th argument. Arg(0) is the first remaining argument
-// after flags have been processed. Arg returns an empty string if the
-// requested element does not exist.
-func (f *FlagSet) Arg(i int) string {
-	if i < 0 || i >= len(f.args) {
-		return ""
-	}
-	return f.args[i]
-}
-
-// Arg returns the i'th command-line argument. Arg(0) is the first remaining argument
-// after flags have been processed. Arg returns an empty string if the
-// requested element does not exist.
-func Arg(i int) string {
-	return CommandLine.Arg(i)
-}
-
-// NArg is the number of arguments remaining after flags have been processed.
-func (f *FlagSet) NArg() int { return len(f.args) }
-
-// NArg is the number of arguments remaining after flags have been processed.
-func NArg() int { return len(CommandLine.args) }
-
-// Args returns the non-flag arguments.
-func (f *FlagSet) Args() []string { return f.args }
-
-// Args returns the non-flag command-line arguments.
-func Args() []string { return CommandLine.args }
-
-// BoolVar defines a bool flag with specified name, default value, and usage string.
-// The argument p points to a bool variable in which to store the value of the flag.
-func (f *FlagSet) BoolVar(p *bool, name string, value bool, usage string) {
-	f.Var(newBoolValue(value, p), name, usage)
-}
-
-// BoolVar defines a bool flag with specified name, default value, and usage string.
-// The argument p points to a bool variable in which to store the value of the flag.
-func BoolVar(p *bool, name string, value bool, usage string) {
-	CommandLine.Var(newBoolValue(value, p), name, usage)
-}
-
-// Bool defines a bool flag with specified name, default value, and usage string.
-// The return value is the address of a bool variable that stores the value of the flag.
-func (f *FlagSet) Bool(name string, value bool, usage string) *bool {
-	p := new(bool)
-	f.BoolVar(p, name, value, usage)
-	return p
-}
-
-// Bool defines a bool flag with specified name, default value, and usage string.
-// The return value is the address of a bool variable that stores the value of the flag.
-func Bool(name string, value bool, usage string) *bool {
-	return CommandLine.Bool(name, value, usage)
-}
-
-// IntVar defines an int flag with specified name, default value, and usage string.
-// The argument p points to an int variable in which to store the value of the flag.
-func (f *FlagSet) IntVar(p *int, name string, value int, usage string) {
-	f.Var(newIntValue(value, p), name, usage)
-}
-
-// IntVar defines an int flag with specified name, default value, and usage string.
-// The argument p points to an int variable in which to store the value of the flag.
-func IntVar(p *int, name string, value int, usage string) {
-	CommandLine.Var(newIntValue(value, p), name, usage)
-}
-
-// Int defines an int flag with specified name, default value, and usage string.
-// The return value is the address of an int variable that stores the value of the flag.
-func (f *FlagSet) Int(name string, value int, usage string) *int {
-	p := new(int)
-	f.IntVar(p, name, value, usage)
-	return p
-}
-
-// Int defines an int flag with specified name, default value, and usage string.
-// The return value is the address of an int variable that stores the value of the flag.
-func Int(name string, value int, usage string) *int {
-	return CommandLine.Int(name, value, usage)
-}
-
-// Int64Var defines an int64 flag with specified name, default value, and usage string.
-// The argument p points to an int64 variable in which to store the value of the flag.
-func (f *FlagSet) Int64Var(p *int64, name string, value int64, usage string) {
-	f.Var(newInt64Value(value, p), name, usage)
-}
-
-// Int64Var defines an int64 flag with specified name, default value, and usage string.
-// The argument p points to an int64 variable in which to store the value of the flag.
-func Int64Var(p *int64, name string, value int64, usage string) {
-	CommandLine.Var(newInt64Value(value, p), name, usage)
-}
-
-// Int64 defines an int64 flag with specified name, default value, and usage string.
-// The return value is the address of an int64 variable that stores the value of the flag.
-func (f *FlagSet) Int64(name string, value int64, usage string) *int64 {
-	p := new(int64)
-	f.Int64Var(p, name, value, usage)
-	return p
-}
-
-// Int64 defines an int64 flag with specified name, default value, and usage string.
-// The return value is the address of an int64 variable that stores the value of the flag.
-func Int64(name string, value int64, usage string) *int64 {
-	return CommandLine.Int64(name, value, usage)
-}
-
-// UintVar defines a uint flag with specified name, default value, and usage string.
-// The argument p points to a uint variable in which to store the value of the flag.
-func (f *FlagSet) UintVar(p *uint, name string, value uint, usage string) {
-	f.Var(newUintValue(value, p), name, usage)
-}
-
-// UintVar defines a uint flag with specified name, default value, and usage string.
-// The argument p points to a uint variable in which to store the value of the flag.
-func UintVar(p *uint, name string, value uint, usage string) {
-	CommandLine.Var(newUintValue(value, p), name, usage)
-}
-
-// Uint defines a uint flag with specified name, default value, and usage string.
-// The return value is the address of a uint variable that stores the value of the flag.
-func (f *FlagSet) Uint(name string, value uint, usage string) *uint {
-	p := new(uint)
-	f.UintVar(p, name, value, usage)
-	return p
-}
-
-// Uint defines a uint flag with specified name, default value, and usage string.
-// The return value is the address of a uint variable that stores the value of the flag.
-func Uint(name string, value uint, usage string) *uint {
-	return CommandLine.Uint(name, value, usage)
-}
-
-// Uint64Var defines a uint64 flag with specified name, default value, and usage string.
-// The argument p points to a uint64 variable in which to store the value of the flag.
-func (f *FlagSet) Uint64Var(p *uint64, name string, value uint64, usage string) {
-	f.Var(newUint64Value(value, p), name, usage)
-}
-
-// Uint64Var defines a uint64 flag with specified name, default value, and usage string.
-// The argument p points to a uint64 variable in which to store the value of the flag.
-func Uint64Var(p *uint64, name string, value uint64, usage string) {
-	CommandLine.Var(newUint64Value(value, p), name, usage)
-}
-
-// Uint64 defines a uint64 flag with specified name, default value, and usage string.
-// The return value is the address of a uint64 variable that stores the value of the flag.
-func (f *FlagSet) Uint64(name string, value uint64, usage string) *uint64 {
-	p := new(uint64)
-	f.Uint64Var(p, name, value, usage)
-	return p
-}
-
-// Uint64 defines a uint64 flag with specified name, default value, and usage string.
-// The return value is the address of a uint64 variable that stores the value of the flag.
-func Uint64(name string, value uint64, usage string) *uint64 {
-	return CommandLine.Uint64(name, value, usage)
-}
-
-// StringVar defines a string flag with specified name, default value, and usage string.
-// The argument p points to a string variable in which to store the value of the flag.
-func (f *FlagSet) StringVar(p *string, name string, value string, usage string) {
-	f.Var(newStringValue(value, p), name, usage)
-}
-
-// StringVar defines a string flag with specified name, default value, and usage string.
-// The argument p points to a string variable in which to store the value of the flag.
-func StringVar(p *string, name string, value string, usage string) {
-	CommandLine.Var(newStringValue(value, p), name, usage)
-}
-
-// String defines a string flag with specified name, default value, and usage string.
-// The return value is the address of a string variable that stores the value of the flag.
-func (f *FlagSet) String(name string, value string, usage string) *string {
-	p := new(string)
-	f.StringVar(p, name, value, usage)
-	return p
-}
-
-// String defines a string flag with specified name, default value, and usage string.
-// The return value is the address of a string variable that stores the value of the flag.
-func String(name string, value string, usage string) *string {
-	return CommandLine.String(name, value, usage)
-}
-
-// Float64Var defines a float64 flag with specified name, default value, and usage string.
-// The argument p points to a float64 variable in which to store the value of the flag.
-func (f *FlagSet) Float64Var(p *float64, name string, value float64, usage string) {
-	f.Var(newFloat64Value(value, p), name, usage)
-}
-
-// Float64Var defines a float64 flag with specified name, default value, and usage string.
-// The argument p points to a float64 variable in which to store the value of the flag.
-func Float64Var(p *float64, name string, value float64, usage string) {
-	CommandLine.Var(newFloat64Value(value, p), name, usage)
-}
-
-// Float64 defines a float64 flag with specified name, default value, and usage string.
-// The return value is the address of a float64 variable that stores the value of the flag.
-func (f *FlagSet) Float64(name string, value float64, usage string) *float64 {
-	p := new(float64)
-	f.Float64Var(p, name, value, usage)
-	return p
-}
-
-// Float64 defines a float64 flag with specified name, default value, and usage string.
-// The return value is the address of a float64 variable that stores the value of the flag.
-func Float64(name string, value float64, usage string) *float64 {
-	return CommandLine.Float64(name, value, usage)
-}
-
-// DurationVar defines a time.Duration flag with specified name, default value, and usage string.
-// The argument p points to a time.Duration variable in which to store the value of the flag.
-// The flag accepts a value acceptable to time.ParseDuration.
-func (f *FlagSet) DurationVar(p *time.Duration, name string, value time.Duration, usage string) {
-	f.Var(newDurationValue(value, p), name, usage)
-}
-
-// DurationVar defines a time.Duration flag with specified name, default value, and usage string.
-// The argument p points to a time.Duration variable in which to store the value of the flag.
-// The flag accepts a value acceptable to time.ParseDuration.
-func DurationVar(p *time.Duration, name string, value time.Duration, usage string) {
-	CommandLine.Var(newDurationValue(value, p), name, usage)
-}
-
-// Duration defines a time.Duration flag with specified name, default value, and usage string.
-// The return value is the address of a time.Duration variable that stores the value of the flag.
-// The flag accepts a value acceptable to time.ParseDuration.
-func (f *FlagSet) Duration(name string, value time.Duration, usage string) *time.Duration {
-	p := new(time.Duration)
-	f.DurationVar(p, name, value, usage)
-	return p
-}
-
-// Duration defines a time.Duration flag with specified name, default value, and usage string.
-// The return value is the address of a time.Duration variable that stores the value of the flag.
-// The flag accepts a value acceptable to time.ParseDuration.
-func Duration(name string, value time.Duration, usage string) *time.Duration {
-	return CommandLine.Duration(name, value, usage)
-}
-
-// Func defines a flag with the specified name and usage string.
-// Each time the flag is seen, fn is called with the value of the flag.
-// If fn returns a non-nil error, it will be treated as a flag value parsing error.
-func (f *FlagSet) Func(name, usage string, fn func(string) error) {
-	f.Var(funcValue(fn), name, usage)
-}
-
-// Func defines a flag with the specified name and usage string.
-// Each time the flag is seen, fn is called with the value of the flag.
-// If fn returns a non-nil error, it will be treated as a flag value parsing error.
-func Func(name, usage string, fn func(string) error) {
-	CommandLine.Func(name, usage, fn)
-}
-
-// Var defines a flag with the specified name and usage string. The type and
-// value of the flag are represented by the first argument, of type Value, which
-// typically holds a user-defined implementation of Value. For instance, the
-// caller could create a flag that turns a comma-separated string into a slice
-// of strings by giving the slice the methods of Value; in particular, Set would
-// decompose the comma-separated string into the slice.
-func (f *FlagSet) Var(value Value, name string, usage string) {
-	// Flag must not begin "-" or contain "=".
-	if strings.HasPrefix(name, "-") {
-		panic(f.sprintf("flag %q begins with -", name))
-	} else if strings.Contains(name, "=") {
-		panic(f.sprintf("flag %q contains =", name))
-	}
-
-	// Remember the default value as a string; it won't change.
-	flag := &Flag{name, usage, value, value.String()}
-	_, alreadythere := f.formal[name]
-	if alreadythere {
-		var msg string
-		if f.name == "" {
-			msg = f.sprintf("flag redefined: %s", name)
-		} else {
-			msg = f.sprintf("%s flag redefined: %s", f.name, name)
-		}
-		panic(msg) // Happens only if flags are declared with identical names
-	}
-	if f.formal == nil {
-		f.formal = make(map[string]*Flag)
-	}
-	f.formal[name] = flag
-}
-
-// Var defines a flag with the specified name and usage string. The type and
-// value of the flag are represented by the first argument, of type Value, which
-// typically holds a user-defined implementation of Value. For instance, the
-// caller could create a flag that turns a comma-separated string into a slice
-// of strings by giving the slice the methods of Value; in particular, Set would
-// decompose the comma-separated string into the slice.
-func Var(value Value, name string, usage string) {
-	CommandLine.Var(value, name, usage)
-}
-
-// sprintf formats the message, prints it to output, and returns it.
-func (f *FlagSet) sprintf(format string, a ...any) string {
-	msg := fmt.Sprintf(format, a...)
-	fmt.Fprintln(f.Output(), msg)
-	return msg
-}
-
-// failf prints to standard error a formatted error and usage message and
-// returns the error.
-func (f *FlagSet) failf(format string, a ...any) error {
-	msg := f.sprintf(format, a...)
-	f.usage()
-	return errors.New(msg)
-}
-
-// usage calls the Usage method for the flag set if one is specified,
-// or the appropriate default usage function otherwise.
-func (f *FlagSet) usage() {
-	if f.Usage == nil {
-		f.defaultUsage()
-	} else {
-		f.Usage()
-	}
-}
-
-// parseOne parses one flag. It reports whether a flag was seen.
-func (f *FlagSet) parseOne() (bool, error) {
-	if len(f.args) == 0 {
-		return false, nil
-	}
-	s := f.args[0]
-	if len(s) < 2 || s[0] != '-' {
-		return false, nil
-	}
-	numMinuses := 1
-	if s[1] == '-' {
-		numMinuses++
-		if len(s) == 2 { // "--" terminates the flags
-			f.args = f.args[1:]
-			return false, nil
-		}
-	}
-	name := s[numMinuses:]
-	if len(name) == 0 || name[0] == '-' || name[0] == '=' {
-		return false, f.failf("bad flag syntax: %s", s)
-	}
-
-	// it's a flag. does it have an argument?
-	f.args = f.args[1:]
-	hasValue := false
-	value := ""
-	for i := 1; i < len(name); i++ { // equals cannot be first
-		if name[i] == '=' {
-			value = name[i+1:]
-			hasValue = true
-			name = name[0:i]
-			break
-		}
-	}
-	m := f.formal
-	flag, alreadythere := m[name] // BUG
-	if !alreadythere {
-		if name == "help" || name == "h" { // special case for nice help message.
-			f.usage()
-			return false, ErrHelp
-		}
-		return false, f.failf("flag provided but not defined: -%s", name)
-	}
-
-	if fv, ok := flag.Value.(boolFlag); ok && fv.IsBoolFlag() { // special case: doesn't need an arg
-		if hasValue {
-			if err := fv.Set(value); err != nil {
-				return false, f.failf("invalid boolean value %q for -%s: %v", value, name, err)
-			}
-		} else {
-			if err := fv.Set("true"); err != nil {
-				return false, f.failf("invalid boolean flag %s: %v", name, err)
-			}
-		}
-	} else {
-		// It must have a value, which might be the next argument.
-		if !hasValue && len(f.args) > 0 {
-			// value is the next arg
-			hasValue = true
-			value, f.args = f.args[0], f.args[1:]
-		}
-		if !hasValue {
-			return false, f.failf("flag needs an argument: -%s", name)
-		}
-		if err := flag.Value.Set(value); err != nil {
-			return false, f.failf("invalid value %q for flag -%s: %v", value, name, err)
-		}
-	}
-	if f.actual == nil {
-		f.actual = make(map[string]*Flag)
-	}
-	f.actual[name] = flag
-	return true, nil
-}
-
-// Parse parses flag definitions from the argument list, which should not
-// include the command name. Must be called after all flags in the FlagSet
-// are defined and before flags are accessed by the program.
-// The return value will be ErrHelp if -help or -h were set but not defined.
-func (f *FlagSet) Parse(arguments []string) error {
-	f.parsed = true
-	f.args = arguments
-	for {
-		seen, err := f.parseOne()
-		if seen {
-			continue
-		}
-		if err == nil {
-			break
-		}
-		switch f.errorHandling {
-		case ContinueOnError:
-			return err
-		case ExitOnError:
-			if err == ErrHelp {
-				os.Exit(0)
-			}
-			os.Exit(2)
-		case PanicOnError:
-			panic(err)
-		}
-	}
-	return nil
-}
-
-// Parsed reports whether f.Parse has been called.
-func (f *FlagSet) Parsed() bool {
-	return f.parsed
-}
-
-// Parse parses the command-line flags from os.Args[1:]. Must be called
-// after all flags are defined and before flags are accessed by the program.
-func Parse() {
-	// Ignore errors; CommandLine is set for ExitOnError.
-	CommandLine.Parse(os.Args[1:])
-}
-
-// Parsed reports whether the command-line flags have been parsed.
-func Parsed() bool {
-	return CommandLine.Parsed()
-}
-
-// CommandLine is the default set of command-line flags, parsed from os.Args.
-// The top-level functions such as BoolVar, Arg, and so on are wrappers for the
-// methods of CommandLine.
-var CommandLine = NewFlagSet(os.Args[0], ExitOnError)
-
-func init() {
-	// Override generic FlagSet default Usage with call to global Usage.
-	// Note: This is not CommandLine.Usage = Usage,
-	// because we want any eventual call to use any updated value of Usage,
-	// not the value it has when this line is run.
-	CommandLine.Usage = commandLineUsage
-}
-
-func commandLineUsage() {
-	Usage()
-}
-
-// NewFlagSet returns a new, empty flag set with the specified name and
-// error handling property. If the name is not empty, it will be printed
-// in the default usage message and in error messages.
-func NewFlagSet(name string, errorHandling ErrorHandling) *FlagSet {
-	f := &FlagSet{
-		name:          name,
-		errorHandling: errorHandling,
-	}
-	f.Usage = f.defaultUsage
-	return f
-}
-
-// Init sets the name and error handling property for a flag set.
-// By default, the zero FlagSet uses an empty name and the
-// ContinueOnError error handling policy.
-func (f *FlagSet) Init(name string, errorHandling ErrorHandling) {
-	f.name = name
-	f.errorHandling = errorHandling
-}
diff --git a/contrib/go/_std_1.18/src/fmt/doc.go b/contrib/go/_std_1.18/src/fmt/doc.go
deleted file mode 100644
index c584cc9465..0000000000
--- a/contrib/go/_std_1.18/src/fmt/doc.go
+++ /dev/null
@@ -1,343 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-/*
-	Package fmt implements formatted I/O with functions analogous
-	to C's printf and scanf.  The format 'verbs' are derived from C's but
-	are simpler.
-
-
-	Printing
-
-	The verbs:
-
-	General:
-		%v	the value in a default format
-			when printing structs, the plus flag (%+v) adds field names
-		%#v	a Go-syntax representation of the value
-		%T	a Go-syntax representation of the type of the value
-		%%	a literal percent sign; consumes no value
-
-	Boolean:
-		%t	the word true or false
-	Integer:
-		%b	base 2
-		%c	the character represented by the corresponding Unicode code point
-		%d	base 10
-		%o	base 8
-		%O	base 8 with 0o prefix
-		%q	a single-quoted character literal safely escaped with Go syntax.
-		%x	base 16, with lower-case letters for a-f
-		%X	base 16, with upper-case letters for A-F
-		%U	Unicode format: U+1234; same as "U+%04X"
-	Floating-point and complex constituents:
-		%b	decimalless scientific notation with exponent a power of two,
-			in the manner of strconv.FormatFloat with the 'b' format,
-			e.g. -123456p-78
-		%e	scientific notation, e.g. -1.234456e+78
-		%E	scientific notation, e.g. -1.234456E+78
-		%f	decimal point but no exponent, e.g. 123.456
-		%F	synonym for %f
-		%g	%e for large exponents, %f otherwise. Precision is discussed below.
-		%G	%E for large exponents, %F otherwise
-		%x	hexadecimal notation (with decimal power of two exponent), e.g. -0x1.23abcp+20
-		%X	upper-case hexadecimal notation, e.g. -0X1.23ABCP+20
-	String and slice of bytes (treated equivalently with these verbs):
-		%s	the uninterpreted bytes of the string or slice
-		%q	a double-quoted string safely escaped with Go syntax
-		%x	base 16, lower-case, two characters per byte
-		%X	base 16, upper-case, two characters per byte
-	Slice:
-		%p	address of 0th element in base 16 notation, with leading 0x
-	Pointer:
-		%p	base 16 notation, with leading 0x
-		The %b, %d, %o, %x and %X verbs also work with pointers,
-		formatting the value exactly as if it were an integer.
-
-	The default format for %v is:
-		bool:                    %t
-		int, int8 etc.:          %d
-		uint, uint8 etc.:        %d, %#x if printed with %#v
-		float32, complex64, etc: %g
-		string:                  %s
-		chan:                    %p
-		pointer:                 %p
-	For compound objects, the elements are printed using these rules, recursively,
-	laid out like this:
-		struct:             {field0 field1 ...}
-		array, slice:       [elem0 elem1 ...]
-		maps:               map[key1:value1 key2:value2 ...]
-		pointer to above:   &{}, &[], &map[]
-
-	Width is specified by an optional decimal number immediately preceding the verb.
-	If absent, the width is whatever is necessary to represent the value.
-	Precision is specified after the (optional) width by a period followed by a
-	decimal number. If no period is present, a default precision is used.
-	A period with no following number specifies a precision of zero.
-	Examples:
-		%f     default width, default precision
-		%9f    width 9, default precision
-		%.2f   default width, precision 2
-		%9.2f  width 9, precision 2
-		%9.f   width 9, precision 0
-
-	Width and precision are measured in units of Unicode code points,
-	that is, runes. (This differs from C's printf where the
-	units are always measured in bytes.) Either or both of the flags
-	may be replaced with the character '*', causing their values to be
-	obtained from the next operand (preceding the one to format),
-	which must be of type int.
-
-	For most values, width is the minimum number of runes to output,
-	padding the formatted form with spaces if necessary.
-
-	For strings, byte slices and byte arrays, however, precision
-	limits the length of the input to be formatted (not the size of
-	the output), truncating if necessary. Normally it is measured in
-	runes, but for these types when formatted with the %x or %X format
-	it is measured in bytes.
-
-	For floating-point values, width sets the minimum width of the field and
-	precision sets the number of places after the decimal, if appropriate,
-	except that for %g/%G precision sets the maximum number of significant
-	digits (trailing zeros are removed). For example, given 12.345 the format
-	%6.3f prints 12.345 while %.3g prints 12.3. The default precision for %e, %f
-	and %#g is 6; for %g it is the smallest number of digits necessary to identify
-	the value uniquely.
-
-	For complex numbers, the width and precision apply to the two
-	components independently and the result is parenthesized, so %f applied
-	to 1.2+3.4i produces (1.200000+3.400000i).
-
-	Other flags:
-		+	always print a sign for numeric values;
-			guarantee ASCII-only output for %q (%+q)
-		-	pad with spaces on the right rather than the left (left-justify the field)
-		#	alternate format: add leading 0b for binary (%#b), 0 for octal (%#o),
-			0x or 0X for hex (%#x or %#X); suppress 0x for %p (%#p);
-			for %q, print a raw (backquoted) string if strconv.CanBackquote
-			returns true;
-			always print a decimal point for %e, %E, %f, %F, %g and %G;
-			do not remove trailing zeros for %g and %G;
-			write e.g. U+0078 'x' if the character is printable for %U (%#U).
-		' '	(space) leave a space for elided sign in numbers (% d);
-			put spaces between bytes printing strings or slices in hex (% x, % X)
-		0	pad with leading zeros rather than spaces;
-			for numbers, this moves the padding after the sign
-
-	Flags are ignored by verbs that do not expect them.
-	For example there is no alternate decimal format, so %#d and %d
-	behave identically.
-
-	For each Printf-like function, there is also a Print function
-	that takes no format and is equivalent to saying %v for every
-	operand.  Another variant Println inserts blanks between
-	operands and appends a newline.
-
-	Regardless of the verb, if an operand is an interface value,
-	the internal concrete value is used, not the interface itself.
-	Thus:
-		var i interface{} = 23
-		fmt.Printf("%v\n", i)
-	will print 23.
-
-	Except when printed using the verbs %T and %p, special
-	formatting considerations apply for operands that implement
-	certain interfaces. In order of application:
-
-	1. If the operand is a reflect.Value, the operand is replaced by the
-	concrete value that it holds, and printing continues with the next rule.
-
-	2. If an operand implements the Formatter interface, it will
-	be invoked. In this case the interpretation of verbs and flags is
-	controlled by that implementation.
-
-	3. If the %v verb is used with the # flag (%#v) and the operand
-	implements the GoStringer interface, that will be invoked.
-
-	If the format (which is implicitly %v for Println etc.) is valid
-	for a string (%s %q %v %x %X), the following two rules apply:
-
-	4. If an operand implements the error interface, the Error method
-	will be invoked to convert the object to a string, which will then
-	be formatted as required by the verb (if any).
-
-	5. If an operand implements method String() string, that method
-	will be invoked to convert the object to a string, which will then
-	be formatted as required by the verb (if any).
-
-	For compound operands such as slices and structs, the format
-	applies to the elements of each operand, recursively, not to the
-	operand as a whole. Thus %q will quote each element of a slice
-	of strings, and %6.2f will control formatting for each element
-	of a floating-point array.
-
-	However, when printing a byte slice with a string-like verb
-	(%s %q %x %X), it is treated identically to a string, as a single item.
-
-	To avoid recursion in cases such as
-		type X string
-		func (x X) String() string { return Sprintf("<%s>", x) }
-	convert the value before recurring:
-		func (x X) String() string { return Sprintf("<%s>", string(x)) }
-	Infinite recursion can also be triggered by self-referential data
-	structures, such as a slice that contains itself as an element, if
-	that type has a String method. Such pathologies are rare, however,
-	and the package does not protect against them.
-
-	When printing a struct, fmt cannot and therefore does not invoke
-	formatting methods such as Error or String on unexported fields.
-
-	Explicit argument indexes
-
-	In Printf, Sprintf, and Fprintf, the default behavior is for each
-	formatting verb to format successive arguments passed in the call.
-	However, the notation [n] immediately before the verb indicates that the
-	nth one-indexed argument is to be formatted instead. The same notation
-	before a '*' for a width or precision selects the argument index holding
-	the value. After processing a bracketed expression [n], subsequent verbs
-	will use arguments n+1, n+2, etc. unless otherwise directed.
-
-	For example,
-		fmt.Sprintf("%[2]d %[1]d\n", 11, 22)
-	will yield "22 11", while
-		fmt.Sprintf("%[3]*.[2]*[1]f", 12.0, 2, 6)
-	equivalent to
-		fmt.Sprintf("%6.2f", 12.0)
-	will yield " 12.00". Because an explicit index affects subsequent verbs,
-	this notation can be used to print the same values multiple times
-	by resetting the index for the first argument to be repeated:
-		fmt.Sprintf("%d %d %#[1]x %#x", 16, 17)
-	will yield "16 17 0x10 0x11".
-
-	Format errors
-
-	If an invalid argument is given for a verb, such as providing
-	a string to %d, the generated string will contain a
-	description of the problem, as in these examples:
-
-		Wrong type or unknown verb: %!verb(type=value)
-			Printf("%d", "hi"):        %!d(string=hi)
-		Too many arguments: %!(EXTRA type=value)
-			Printf("hi", "guys"):      hi%!(EXTRA string=guys)
-		Too few arguments: %!verb(MISSING)
-			Printf("hi%d"):            hi%!d(MISSING)
-		Non-int for width or precision: %!(BADWIDTH) or %!(BADPREC)
-			Printf("%*s", 4.5, "hi"):  %!(BADWIDTH)hi
-			Printf("%.*s", 4.5, "hi"): %!(BADPREC)hi
-		Invalid or invalid use of argument index: %!(BADINDEX)
-			Printf("%*[2]d", 7):       %!d(BADINDEX)
-			Printf("%.[2]d", 7):       %!d(BADINDEX)
-
-	All errors begin with the string "%!" followed sometimes
-	by a single character (the verb) and end with a parenthesized
-	description.
-
-	If an Error or String method triggers a panic when called by a
-	print routine, the fmt package reformats the error message
-	from the panic, decorating it with an indication that it came
-	through the fmt package.  For example, if a String method
-	calls panic("bad"), the resulting formatted message will look
-	like
-		%!s(PANIC=bad)
-
-	The %!s just shows the print verb in use when the failure
-	occurred. If the panic is caused by a nil receiver to an Error
-	or String method, however, the output is the undecorated
-	string, "<nil>".
-
-	Scanning
-
-	An analogous set of functions scans formatted text to yield
-	values.  Scan, Scanf and Scanln read from os.Stdin; Fscan,
-	Fscanf and Fscanln read from a specified io.Reader; Sscan,
-	Sscanf and Sscanln read from an argument string.
-
-	Scan, Fscan, Sscan treat newlines in the input as spaces.
-
-	Scanln, Fscanln and Sscanln stop scanning at a newline and
-	require that the items be followed by a newline or EOF.
-
-	Scanf, Fscanf, and Sscanf parse the arguments according to a
-	format string, analogous to that of Printf. In the text that
-	follows, 'space' means any Unicode whitespace character
-	except newline.
-
-	In the format string, a verb introduced by the % character
-	consumes and parses input; these verbs are described in more
-	detail below. A character other than %, space, or newline in
-	the format consumes exactly that input character, which must
-	be present. A newline with zero or more spaces before it in
-	the format string consumes zero or more spaces in the input
-	followed by a single newline or the end of the input. A space
-	following a newline in the format string consumes zero or more
-	spaces in the input. Otherwise, any run of one or more spaces
-	in the format string consumes as many spaces as possible in
-	the input. Unless the run of spaces in the format string
-	appears adjacent to a newline, the run must consume at least
-	one space from the input or find the end of the input.
-
-	The handling of spaces and newlines differs from that of C's
-	scanf family: in C, newlines are treated as any other space,
-	and it is never an error when a run of spaces in the format
-	string finds no spaces to consume in the input.
-
-	The verbs behave analogously to those of Printf.
-	For example, %x will scan an integer as a hexadecimal number,
-	and %v will scan the default representation format for the value.
-	The Printf verbs %p and %T and the flags # and + are not implemented.
-	For floating-point and complex values, all valid formatting verbs
-	(%b %e %E %f %F %g %G %x %X and %v) are equivalent and accept
-	both decimal and hexadecimal notation (for example: "2.3e+7", "0x4.5p-8")
-	and digit-separating underscores (for example: "3.14159_26535_89793").
-
-	Input processed by verbs is implicitly space-delimited: the
-	implementation of every verb except %c starts by discarding
-	leading spaces from the remaining input, and the %s verb
-	(and %v reading into a string) stops consuming input at the first
-	space or newline character.
-
-	The familiar base-setting prefixes 0b (binary), 0o and 0 (octal),
-	and 0x (hexadecimal) are accepted when scanning integers
-	without a format or with the %v verb, as are digit-separating
-	underscores.
-
-	Width is interpreted in the input text but there is no
-	syntax for scanning with a precision (no %5.2f, just %5f).
-	If width is provided, it applies after leading spaces are
-	trimmed and specifies the maximum number of runes to read
-	to satisfy the verb. For example,
-	   Sscanf(" 1234567 ", "%5s%d", &s, &i)
-	will set s to "12345" and i to 67 while
-	   Sscanf(" 12 34 567 ", "%5s%d", &s, &i)
-	will set s to "12" and i to 34.
-
-	In all the scanning functions, a carriage return followed
-	immediately by a newline is treated as a plain newline
-	(\r\n means the same as \n).
-
-	In all the scanning functions, if an operand implements method
-	Scan (that is, it implements the Scanner interface) that
-	method will be used to scan the text for that operand.  Also,
-	if the number of arguments scanned is less than the number of
-	arguments provided, an error is returned.
-
-	All arguments to be scanned must be either pointers to basic
-	types or implementations of the Scanner interface.
-
-	Like Scanf and Fscanf, Sscanf need not consume its entire input.
-	There is no way to recover how much of the input string Sscanf used.
-
-	Note: Fscan etc. can read one character (rune) past the input
-	they return, which means that a loop calling a scan routine
-	may skip some of the input.  This is usually a problem only
-	when there is no space between input values.  If the reader
-	provided to Fscan implements ReadRune, that method will be used
-	to read characters.  If the reader also implements UnreadRune,
-	that method will be used to save the character and successive
-	calls will not lose data.  To attach ReadRune and UnreadRune
-	methods to a reader without that capability, use
-	bufio.NewReader.
-*/
-package fmt
diff --git a/contrib/go/_std_1.18/src/fmt/print.go b/contrib/go/_std_1.18/src/fmt/print.go
deleted file mode 100644
index 1c37c3cb7b..0000000000
--- a/contrib/go/_std_1.18/src/fmt/print.go
+++ /dev/null
@@ -1,1172 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package fmt
-
-import (
-	"internal/fmtsort"
-	"io"
-	"os"
-	"reflect"
-	"sync"
-	"unicode/utf8"
-)
-
-// Strings for use with buffer.WriteString.
-// This is less overhead than using buffer.Write with byte arrays.
-const (
-	commaSpaceString  = ", "
-	nilAngleString    = "<nil>"
-	nilParenString    = "(nil)"
-	nilString         = "nil"
-	mapString         = "map["
-	percentBangString = "%!"
-	missingString     = "(MISSING)"
-	badIndexString    = "(BADINDEX)"
-	panicString       = "(PANIC="
-	extraString       = "%!(EXTRA "
-	badWidthString    = "%!(BADWIDTH)"
-	badPrecString     = "%!(BADPREC)"
-	noVerbString      = "%!(NOVERB)"
-	invReflectString  = "<invalid reflect.Value>"
-)
-
-// State represents the printer state passed to custom formatters.
-// It provides access to the io.Writer interface plus information about
-// the flags and options for the operand's format specifier.
-type State interface {
-	// Write is the function to call to emit formatted output to be printed.
-	Write(b []byte) (n int, err error)
-	// Width returns the value of the width option and whether it has been set.
-	Width() (wid int, ok bool)
-	// Precision returns the value of the precision option and whether it has been set.
-	Precision() (prec int, ok bool)
-
-	// Flag reports whether the flag c, a character, has been set.
-	Flag(c int) bool
-}
-
-// Formatter is implemented by any value that has a Format method.
-// The implementation controls how State and rune are interpreted,
-// and may call Sprint(f) or Fprint(f) etc. to generate its output.
-type Formatter interface {
-	Format(f State, verb rune)
-}
-
-// Stringer is implemented by any value that has a String method,
-// which defines the ``native'' format for that value.
-// The String method is used to print values passed as an operand
-// to any format that accepts a string or to an unformatted printer
-// such as Print.
-type Stringer interface {
-	String() string
-}
-
-// GoStringer is implemented by any value that has a GoString method,
-// which defines the Go syntax for that value.
-// The GoString method is used to print values passed as an operand
-// to a %#v format.
-type GoStringer interface {
-	GoString() string
-}
-
-// Use simple []byte instead of bytes.Buffer to avoid large dependency.
-type buffer []byte
-
-func (b *buffer) write(p []byte) {
-	*b = append(*b, p...)
-}
-
-func (b *buffer) writeString(s string) {
-	*b = append(*b, s...)
-}
-
-func (b *buffer) writeByte(c byte) {
-	*b = append(*b, c)
-}
-
-func (bp *buffer) writeRune(r rune) {
-	if r < utf8.RuneSelf {
-		*bp = append(*bp, byte(r))
-		return
-	}
-
-	b := *bp
-	n := len(b)
-	for n+utf8.UTFMax > cap(b) {
-		b = append(b, 0)
-	}
-	w := utf8.EncodeRune(b[n:n+utf8.UTFMax], r)
-	*bp = b[:n+w]
-}
-
-// pp is used to store a printer's state and is reused with sync.Pool to avoid allocations.
-type pp struct {
-	buf buffer
-
-	// arg holds the current item, as an interface{}.
-	arg any
-
-	// value is used instead of arg for reflect values.
-	value reflect.Value
-
-	// fmt is used to format basic items such as integers or strings.
-	fmt fmt
-
-	// reordered records whether the format string used argument reordering.
-	reordered bool
-	// goodArgNum records whether the most recent reordering directive was valid.
-	goodArgNum bool
-	// panicking is set by catchPanic to avoid infinite panic, recover, panic, ... recursion.
-	panicking bool
-	// erroring is set when printing an error string to guard against calling handleMethods.
-	erroring bool
-	// wrapErrs is set when the format string may contain a %w verb.
-	wrapErrs bool
-	// wrappedErr records the target of the %w verb.
-	wrappedErr error
-}
-
-var ppFree = sync.Pool{
-	New: func() any { return new(pp) },
-}
-
-// newPrinter allocates a new pp struct or grabs a cached one.
-func newPrinter() *pp {
-	p := ppFree.Get().(*pp)
-	p.panicking = false
-	p.erroring = false
-	p.wrapErrs = false
-	p.fmt.init(&p.buf)
-	return p
-}
-
-// free saves used pp structs in ppFree; avoids an allocation per invocation.
-func (p *pp) free() {
-	// Proper usage of a sync.Pool requires each entry to have approximately
-	// the same memory cost. To obtain this property when the stored type
-	// contains a variably-sized buffer, we add a hard limit on the maximum buffer
-	// to place back in the pool.
-	//
-	// See https://golang.org/issue/23199
-	if cap(p.buf) > 64<<10 {
-		return
-	}
-
-	p.buf = p.buf[:0]
-	p.arg = nil
-	p.value = reflect.Value{}
-	p.wrappedErr = nil
-	ppFree.Put(p)
-}
-
-func (p *pp) Width() (wid int, ok bool) { return p.fmt.wid, p.fmt.widPresent }
-
-func (p *pp) Precision() (prec int, ok bool) { return p.fmt.prec, p.fmt.precPresent }
-
-func (p *pp) Flag(b int) bool {
-	switch b {
-	case '-':
-		return p.fmt.minus
-	case '+':
-		return p.fmt.plus || p.fmt.plusV
-	case '#':
-		return p.fmt.sharp || p.fmt.sharpV
-	case ' ':
-		return p.fmt.space
-	case '0':
-		return p.fmt.zero
-	}
-	return false
-}
-
-// Implement Write so we can call Fprintf on a pp (through State), for
-// recursive use in custom verbs.
-func (p *pp) Write(b []byte) (ret int, err error) {
-	p.buf.write(b)
-	return len(b), nil
-}
-
-// Implement WriteString so that we can call io.WriteString
-// on a pp (through state), for efficiency.
-func (p *pp) WriteString(s string) (ret int, err error) {
-	p.buf.writeString(s)
-	return len(s), nil
-}
-
-// These routines end in 'f' and take a format string.
-
-// Fprintf formats according to a format specifier and writes to w.
-// It returns the number of bytes written and any write error encountered.
-func Fprintf(w io.Writer, format string, a ...any) (n int, err error) {
-	p := newPrinter()
-	p.doPrintf(format, a)
-	n, err = w.Write(p.buf)
-	p.free()
-	return
-}
-
-// Printf formats according to a format specifier and writes to standard output.
-// It returns the number of bytes written and any write error encountered.
-func Printf(format string, a ...any) (n int, err error) {
-	return Fprintf(os.Stdout, format, a...)
-}
-
-// Sprintf formats according to a format specifier and returns the resulting string.
-func Sprintf(format string, a ...any) string {
-	p := newPrinter()
-	p.doPrintf(format, a)
-	s := string(p.buf)
-	p.free()
-	return s
-}
-
-// These routines do not take a format string
-
-// Fprint formats using the default formats for its operands and writes to w.
-// Spaces are added between operands when neither is a string.
-// It returns the number of bytes written and any write error encountered.
-func Fprint(w io.Writer, a ...any) (n int, err error) {
-	p := newPrinter()
-	p.doPrint(a)
-	n, err = w.Write(p.buf)
-	p.free()
-	return
-}
-
-// Print formats using the default formats for its operands and writes to standard output.
-// Spaces are added between operands when neither is a string.
-// It returns the number of bytes written and any write error encountered.
-func Print(a ...any) (n int, err error) {
-	return Fprint(os.Stdout, a...)
-}
-
-// Sprint formats using the default formats for its operands and returns the resulting string.
-// Spaces are added between operands when neither is a string.
-func Sprint(a ...any) string {
-	p := newPrinter()
-	p.doPrint(a)
-	s := string(p.buf)
-	p.free()
-	return s
-}
-
-// These routines end in 'ln', do not take a format string,
-// always add spaces between operands, and add a newline
-// after the last operand.
-
-// Fprintln formats using the default formats for its operands and writes to w.
-// Spaces are always added between operands and a newline is appended.
-// It returns the number of bytes written and any write error encountered.
-func Fprintln(w io.Writer, a ...any) (n int, err error) {
-	p := newPrinter()
-	p.doPrintln(a)
-	n, err = w.Write(p.buf)
-	p.free()
-	return
-}
-
-// Println formats using the default formats for its operands and writes to standard output.
-// Spaces are always added between operands and a newline is appended.
-// It returns the number of bytes written and any write error encountered.
-func Println(a ...any) (n int, err error) {
-	return Fprintln(os.Stdout, a...)
-}
-
-// Sprintln formats using the default formats for its operands and returns the resulting string.
-// Spaces are always added between operands and a newline is appended.
-func Sprintln(a ...any) string {
-	p := newPrinter()
-	p.doPrintln(a)
-	s := string(p.buf)
-	p.free()
-	return s
-}
-
-// getField gets the i'th field of the struct value.
-// If the field is itself is an interface, return a value for
-// the thing inside the interface, not the interface itself.
-func getField(v reflect.Value, i int) reflect.Value {
-	val := v.Field(i)
-	if val.Kind() == reflect.Interface && !val.IsNil() {
-		val = val.Elem()
-	}
-	return val
-}
-
-// tooLarge reports whether the magnitude of the integer is
-// too large to be used as a formatting width or precision.
-func tooLarge(x int) bool {
-	const max int = 1e6
-	return x > max || x < -max
-}
-
-// parsenum converts ASCII to integer.  num is 0 (and isnum is false) if no number present.
-func parsenum(s string, start, end int) (num int, isnum bool, newi int) {
-	if start >= end {
-		return 0, false, end
-	}
-	for newi = start; newi < end && '0' <= s[newi] && s[newi] <= '9'; newi++ {
-		if tooLarge(num) {
-			return 0, false, end // Overflow; crazy long number most likely.
-		}
-		num = num*10 + int(s[newi]-'0')
-		isnum = true
-	}
-	return
-}
-
-func (p *pp) unknownType(v reflect.Value) {
-	if !v.IsValid() {
-		p.buf.writeString(nilAngleString)
-		return
-	}
-	p.buf.writeByte('?')
-	p.buf.writeString(v.Type().String())
-	p.buf.writeByte('?')
-}
-
-func (p *pp) badVerb(verb rune) {
-	p.erroring = true
-	p.buf.writeString(percentBangString)
-	p.buf.writeRune(verb)
-	p.buf.writeByte('(')
-	switch {
-	case p.arg != nil:
-		p.buf.writeString(reflect.TypeOf(p.arg).String())
-		p.buf.writeByte('=')
-		p.printArg(p.arg, 'v')
-	case p.value.IsValid():
-		p.buf.writeString(p.value.Type().String())
-		p.buf.writeByte('=')
-		p.printValue(p.value, 'v', 0)
-	default:
-		p.buf.writeString(nilAngleString)
-	}
-	p.buf.writeByte(')')
-	p.erroring = false
-}
-
-func (p *pp) fmtBool(v bool, verb rune) {
-	switch verb {
-	case 't', 'v':
-		p.fmt.fmtBoolean(v)
-	default:
-		p.badVerb(verb)
-	}
-}
-
-// fmt0x64 formats a uint64 in hexadecimal and prefixes it with 0x or
-// not, as requested, by temporarily setting the sharp flag.
-func (p *pp) fmt0x64(v uint64, leading0x bool) {
-	sharp := p.fmt.sharp
-	p.fmt.sharp = leading0x
-	p.fmt.fmtInteger(v, 16, unsigned, 'v', ldigits)
-	p.fmt.sharp = sharp
-}
-
-// fmtInteger formats a signed or unsigned integer.
-func (p *pp) fmtInteger(v uint64, isSigned bool, verb rune) {
-	switch verb {
-	case 'v':
-		if p.fmt.sharpV && !isSigned {
-			p.fmt0x64(v, true)
-		} else {
-			p.fmt.fmtInteger(v, 10, isSigned, verb, ldigits)
-		}
-	case 'd':
-		p.fmt.fmtInteger(v, 10, isSigned, verb, ldigits)
-	case 'b':
-		p.fmt.fmtInteger(v, 2, isSigned, verb, ldigits)
-	case 'o', 'O':
-		p.fmt.fmtInteger(v, 8, isSigned, verb, ldigits)
-	case 'x':
-		p.fmt.fmtInteger(v, 16, isSigned, verb, ldigits)
-	case 'X':
-		p.fmt.fmtInteger(v, 16, isSigned, verb, udigits)
-	case 'c':
-		p.fmt.fmtC(v)
-	case 'q':
-		p.fmt.fmtQc(v)
-	case 'U':
-		p.fmt.fmtUnicode(v)
-	default:
-		p.badVerb(verb)
-	}
-}
-
-// fmtFloat formats a float. The default precision for each verb
-// is specified as last argument in the call to fmt_float.
-func (p *pp) fmtFloat(v float64, size int, verb rune) {
-	switch verb {
-	case 'v':
-		p.fmt.fmtFloat(v, size, 'g', -1)
-	case 'b', 'g', 'G', 'x', 'X':
-		p.fmt.fmtFloat(v, size, verb, -1)
-	case 'f', 'e', 'E':
-		p.fmt.fmtFloat(v, size, verb, 6)
-	case 'F':
-		p.fmt.fmtFloat(v, size, 'f', 6)
-	default:
-		p.badVerb(verb)
-	}
-}
-
-// fmtComplex formats a complex number v with
-// r = real(v) and j = imag(v) as (r+ji) using
-// fmtFloat for r and j formatting.
-func (p *pp) fmtComplex(v complex128, size int, verb rune) {
-	// Make sure any unsupported verbs are found before the
-	// calls to fmtFloat to not generate an incorrect error string.
-	switch verb {
-	case 'v', 'b', 'g', 'G', 'x', 'X', 'f', 'F', 'e', 'E':
-		oldPlus := p.fmt.plus
-		p.buf.writeByte('(')
-		p.fmtFloat(real(v), size/2, verb)
-		// Imaginary part always has a sign.
-		p.fmt.plus = true
-		p.fmtFloat(imag(v), size/2, verb)
-		p.buf.writeString("i)")
-		p.fmt.plus = oldPlus
-	default:
-		p.badVerb(verb)
-	}
-}
-
-func (p *pp) fmtString(v string, verb rune) {
-	switch verb {
-	case 'v':
-		if p.fmt.sharpV {
-			p.fmt.fmtQ(v)
-		} else {
-			p.fmt.fmtS(v)
-		}
-	case 's':
-		p.fmt.fmtS(v)
-	case 'x':
-		p.fmt.fmtSx(v, ldigits)
-	case 'X':
-		p.fmt.fmtSx(v, udigits)
-	case 'q':
-		p.fmt.fmtQ(v)
-	default:
-		p.badVerb(verb)
-	}
-}
-
-func (p *pp) fmtBytes(v []byte, verb rune, typeString string) {
-	switch verb {
-	case 'v', 'd':
-		if p.fmt.sharpV {
-			p.buf.writeString(typeString)
-			if v == nil {
-				p.buf.writeString(nilParenString)
-				return
-			}
-			p.buf.writeByte('{')
-			for i, c := range v {
-				if i > 0 {
-					p.buf.writeString(commaSpaceString)
-				}
-				p.fmt0x64(uint64(c), true)
-			}
-			p.buf.writeByte('}')
-		} else {
-			p.buf.writeByte('[')
-			for i, c := range v {
-				if i > 0 {
-					p.buf.writeByte(' ')
-				}
-				p.fmt.fmtInteger(uint64(c), 10, unsigned, verb, ldigits)
-			}
-			p.buf.writeByte(']')
-		}
-	case 's':
-		p.fmt.fmtBs(v)
-	case 'x':
-		p.fmt.fmtBx(v, ldigits)
-	case 'X':
-		p.fmt.fmtBx(v, udigits)
-	case 'q':
-		p.fmt.fmtQ(string(v))
-	default:
-		p.printValue(reflect.ValueOf(v), verb, 0)
-	}
-}
-
-func (p *pp) fmtPointer(value reflect.Value, verb rune) {
-	var u uintptr
-	switch value.Kind() {
-	case reflect.Chan, reflect.Func, reflect.Map, reflect.Pointer, reflect.Slice, reflect.UnsafePointer:
-		u = value.Pointer()
-	default:
-		p.badVerb(verb)
-		return
-	}
-
-	switch verb {
-	case 'v':
-		if p.fmt.sharpV {
-			p.buf.writeByte('(')
-			p.buf.writeString(value.Type().String())
-			p.buf.writeString(")(")
-			if u == 0 {
-				p.buf.writeString(nilString)
-			} else {
-				p.fmt0x64(uint64(u), true)
-			}
-			p.buf.writeByte(')')
-		} else {
-			if u == 0 {
-				p.fmt.padString(nilAngleString)
-			} else {
-				p.fmt0x64(uint64(u), !p.fmt.sharp)
-			}
-		}
-	case 'p':
-		p.fmt0x64(uint64(u), !p.fmt.sharp)
-	case 'b', 'o', 'd', 'x', 'X':
-		p.fmtInteger(uint64(u), unsigned, verb)
-	default:
-		p.badVerb(verb)
-	}
-}
-
-func (p *pp) catchPanic(arg any, verb rune, method string) {
-	if err := recover(); err != nil {
-		// If it's a nil pointer, just say "<nil>". The likeliest causes are a
-		// Stringer that fails to guard against nil or a nil pointer for a
-		// value receiver, and in either case, "<nil>" is a nice result.
-		if v := reflect.ValueOf(arg); v.Kind() == reflect.Pointer && v.IsNil() {
-			p.buf.writeString(nilAngleString)
-			return
-		}
-		// Otherwise print a concise panic message. Most of the time the panic
-		// value will print itself nicely.
-		if p.panicking {
-			// Nested panics; the recursion in printArg cannot succeed.
-			panic(err)
-		}
-
-		oldFlags := p.fmt.fmtFlags
-		// For this output we want default behavior.
-		p.fmt.clearflags()
-
-		p.buf.writeString(percentBangString)
-		p.buf.writeRune(verb)
-		p.buf.writeString(panicString)
-		p.buf.writeString(method)
-		p.buf.writeString(" method: ")
-		p.panicking = true
-		p.printArg(err, 'v')
-		p.panicking = false
-		p.buf.writeByte(')')
-
-		p.fmt.fmtFlags = oldFlags
-	}
-}
-
-func (p *pp) handleMethods(verb rune) (handled bool) {
-	if p.erroring {
-		return
-	}
-	if verb == 'w' {
-		// It is invalid to use %w other than with Errorf, more than once,
-		// or with a non-error arg.
-		err, ok := p.arg.(error)
-		if !ok || !p.wrapErrs || p.wrappedErr != nil {
-			p.wrappedErr = nil
-			p.wrapErrs = false
-			p.badVerb(verb)
-			return true
-		}
-		p.wrappedErr = err
-		// If the arg is a Formatter, pass 'v' as the verb to it.
-		verb = 'v'
-	}
-
-	// Is it a Formatter?
-	if formatter, ok := p.arg.(Formatter); ok {
-		handled = true
-		defer p.catchPanic(p.arg, verb, "Format")
-		formatter.Format(p, verb)
-		return
-	}
-
-	// If we're doing Go syntax and the argument knows how to supply it, take care of it now.
-	if p.fmt.sharpV {
-		if stringer, ok := p.arg.(GoStringer); ok {
-			handled = true
-			defer p.catchPanic(p.arg, verb, "GoString")
-			// Print the result of GoString unadorned.
-			p.fmt.fmtS(stringer.GoString())
-			return
-		}
-	} else {
-		// If a string is acceptable according to the format, see if
-		// the value satisfies one of the string-valued interfaces.
-		// Println etc. set verb to %v, which is "stringable".
-		switch verb {
-		case 'v', 's', 'x', 'X', 'q':
-			// Is it an error or Stringer?
-			// The duplication in the bodies is necessary:
-			// setting handled and deferring catchPanic
-			// must happen before calling the method.
-			switch v := p.arg.(type) {
-			case error:
-				handled = true
-				defer p.catchPanic(p.arg, verb, "Error")
-				p.fmtString(v.Error(), verb)
-				return
-
-			case Stringer:
-				handled = true
-				defer p.catchPanic(p.arg, verb, "String")
-				p.fmtString(v.String(), verb)
-				return
-			}
-		}
-	}
-	return false
-}
-
-func (p *pp) printArg(arg any, verb rune) {
-	p.arg = arg
-	p.value = reflect.Value{}
-
-	if arg == nil {
-		switch verb {
-		case 'T', 'v':
-			p.fmt.padString(nilAngleString)
-		default:
-			p.badVerb(verb)
-		}
-		return
-	}
-
-	// Special processing considerations.
-	// %T (the value's type) and %p (its address) are special; we always do them first.
-	switch verb {
-	case 'T':
-		p.fmt.fmtS(reflect.TypeOf(arg).String())
-		return
-	case 'p':
-		p.fmtPointer(reflect.ValueOf(arg), 'p')
-		return
-	}
-
-	// Some types can be done without reflection.
-	switch f := arg.(type) {
-	case bool:
-		p.fmtBool(f, verb)
-	case float32:
-		p.fmtFloat(float64(f), 32, verb)
-	case float64:
-		p.fmtFloat(f, 64, verb)
-	case complex64:
-		p.fmtComplex(complex128(f), 64, verb)
-	case complex128:
-		p.fmtComplex(f, 128, verb)
-	case int:
-		p.fmtInteger(uint64(f), signed, verb)
-	case int8:
-		p.fmtInteger(uint64(f), signed, verb)
-	case int16:
-		p.fmtInteger(uint64(f), signed, verb)
-	case int32:
-		p.fmtInteger(uint64(f), signed, verb)
-	case int64:
-		p.fmtInteger(uint64(f), signed, verb)
-	case uint:
-		p.fmtInteger(uint64(f), unsigned, verb)
-	case uint8:
-		p.fmtInteger(uint64(f), unsigned, verb)
-	case uint16:
-		p.fmtInteger(uint64(f), unsigned, verb)
-	case uint32:
-		p.fmtInteger(uint64(f), unsigned, verb)
-	case uint64:
-		p.fmtInteger(f, unsigned, verb)
-	case uintptr:
-		p.fmtInteger(uint64(f), unsigned, verb)
-	case string:
-		p.fmtString(f, verb)
-	case []byte:
-		p.fmtBytes(f, verb, "[]byte")
-	case reflect.Value:
-		// Handle extractable values with special methods
-		// since printValue does not handle them at depth 0.
-		if f.IsValid() && f.CanInterface() {
-			p.arg = f.Interface()
-			if p.handleMethods(verb) {
-				return
-			}
-		}
-		p.printValue(f, verb, 0)
-	default:
-		// If the type is not simple, it might have methods.
-		if !p.handleMethods(verb) {
-			// Need to use reflection, since the type had no
-			// interface methods that could be used for formatting.
-			p.printValue(reflect.ValueOf(f), verb, 0)
-		}
-	}
-}
-
-// printValue is similar to printArg but starts with a reflect value, not an interface{} value.
-// It does not handle 'p' and 'T' verbs because these should have been already handled by printArg.
-func (p *pp) printValue(value reflect.Value, verb rune, depth int) {
-	// Handle values with special methods if not already handled by printArg (depth == 0).
-	if depth > 0 && value.IsValid() && value.CanInterface() {
-		p.arg = value.Interface()
-		if p.handleMethods(verb) {
-			return
-		}
-	}
-	p.arg = nil
-	p.value = value
-
-	switch f := value; value.Kind() {
-	case reflect.Invalid:
-		if depth == 0 {
-			p.buf.writeString(invReflectString)
-		} else {
-			switch verb {
-			case 'v':
-				p.buf.writeString(nilAngleString)
-			default:
-				p.badVerb(verb)
-			}
-		}
-	case reflect.Bool:
-		p.fmtBool(f.Bool(), verb)
-	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
-		p.fmtInteger(uint64(f.Int()), signed, verb)
-	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
-		p.fmtInteger(f.Uint(), unsigned, verb)
-	case reflect.Float32:
-		p.fmtFloat(f.Float(), 32, verb)
-	case reflect.Float64:
-		p.fmtFloat(f.Float(), 64, verb)
-	case reflect.Complex64:
-		p.fmtComplex(f.Complex(), 64, verb)
-	case reflect.Complex128:
-		p.fmtComplex(f.Complex(), 128, verb)
-	case reflect.String:
-		p.fmtString(f.String(), verb)
-	case reflect.Map:
-		if p.fmt.sharpV {
-			p.buf.writeString(f.Type().String())
-			if f.IsNil() {
-				p.buf.writeString(nilParenString)
-				return
-			}
-			p.buf.writeByte('{')
-		} else {
-			p.buf.writeString(mapString)
-		}
-		sorted := fmtsort.Sort(f)
-		for i, key := range sorted.Key {
-			if i > 0 {
-				if p.fmt.sharpV {
-					p.buf.writeString(commaSpaceString)
-				} else {
-					p.buf.writeByte(' ')
-				}
-			}
-			p.printValue(key, verb, depth+1)
-			p.buf.writeByte(':')
-			p.printValue(sorted.Value[i], verb, depth+1)
-		}
-		if p.fmt.sharpV {
-			p.buf.writeByte('}')
-		} else {
-			p.buf.writeByte(']')
-		}
-	case reflect.Struct:
-		if p.fmt.sharpV {
-			p.buf.writeString(f.Type().String())
-		}
-		p.buf.writeByte('{')
-		for i := 0; i < f.NumField(); i++ {
-			if i > 0 {
-				if p.fmt.sharpV {
-					p.buf.writeString(commaSpaceString)
-				} else {
-					p.buf.writeByte(' ')
-				}
-			}
-			if p.fmt.plusV || p.fmt.sharpV {
-				if name := f.Type().Field(i).Name; name != "" {
-					p.buf.writeString(name)
-					p.buf.writeByte(':')
-				}
-			}
-			p.printValue(getField(f, i), verb, depth+1)
-		}
-		p.buf.writeByte('}')
-	case reflect.Interface:
-		value := f.Elem()
-		if !value.IsValid() {
-			if p.fmt.sharpV {
-				p.buf.writeString(f.Type().String())
-				p.buf.writeString(nilParenString)
-			} else {
-				p.buf.writeString(nilAngleString)
-			}
-		} else {
-			p.printValue(value, verb, depth+1)
-		}
-	case reflect.Array, reflect.Slice:
-		switch verb {
-		case 's', 'q', 'x', 'X':
-			// Handle byte and uint8 slices and arrays special for the above verbs.
-			t := f.Type()
-			if t.Elem().Kind() == reflect.Uint8 {
-				var bytes []byte
-				if f.Kind() == reflect.Slice {
-					bytes = f.Bytes()
-				} else if f.CanAddr() {
-					bytes = f.Slice(0, f.Len()).Bytes()
-				} else {
-					// We have an array, but we cannot Slice() a non-addressable array,
-					// so we build a slice by hand. This is a rare case but it would be nice
-					// if reflection could help a little more.
-					bytes = make([]byte, f.Len())
-					for i := range bytes {
-						bytes[i] = byte(f.Index(i).Uint())
-					}
-				}
-				p.fmtBytes(bytes, verb, t.String())
-				return
-			}
-		}
-		if p.fmt.sharpV {
-			p.buf.writeString(f.Type().String())
-			if f.Kind() == reflect.Slice && f.IsNil() {
-				p.buf.writeString(nilParenString)
-				return
-			}
-			p.buf.writeByte('{')
-			for i := 0; i < f.Len(); i++ {
-				if i > 0 {
-					p.buf.writeString(commaSpaceString)
-				}
-				p.printValue(f.Index(i), verb, depth+1)
-			}
-			p.buf.writeByte('}')
-		} else {
-			p.buf.writeByte('[')
-			for i := 0; i < f.Len(); i++ {
-				if i > 0 {
-					p.buf.writeByte(' ')
-				}
-				p.printValue(f.Index(i), verb, depth+1)
-			}
-			p.buf.writeByte(']')
-		}
-	case reflect.Pointer:
-		// pointer to array or slice or struct? ok at top level
-		// but not embedded (avoid loops)
-		if depth == 0 && f.Pointer() != 0 {
-			switch a := f.Elem(); a.Kind() {
-			case reflect.Array, reflect.Slice, reflect.Struct, reflect.Map:
-				p.buf.writeByte('&')
-				p.printValue(a, verb, depth+1)
-				return
-			}
-		}
-		fallthrough
-	case reflect.Chan, reflect.Func, reflect.UnsafePointer:
-		p.fmtPointer(f, verb)
-	default:
-		p.unknownType(f)
-	}
-}
-
-// intFromArg gets the argNumth element of a. On return, isInt reports whether the argument has integer type.
-func intFromArg(a []any, argNum int) (num int, isInt bool, newArgNum int) {
-	newArgNum = argNum
-	if argNum < len(a) {
-		num, isInt = a[argNum].(int) // Almost always OK.
-		if !isInt {
-			// Work harder.
-			switch v := reflect.ValueOf(a[argNum]); v.Kind() {
-			case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
-				n := v.Int()
-				if int64(int(n)) == n {
-					num = int(n)
-					isInt = true
-				}
-			case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
-				n := v.Uint()
-				if int64(n) >= 0 && uint64(int(n)) == n {
-					num = int(n)
-					isInt = true
-				}
-			default:
-				// Already 0, false.
-			}
-		}
-		newArgNum = argNum + 1
-		if tooLarge(num) {
-			num = 0
-			isInt = false
-		}
-	}
-	return
-}
-
-// parseArgNumber returns the value of the bracketed number, minus 1
-// (explicit argument numbers are one-indexed but we want zero-indexed).
-// The opening bracket is known to be present at format[0].
-// The returned values are the index, the number of bytes to consume
-// up to the closing paren, if present, and whether the number parsed
-// ok. The bytes to consume will be 1 if no closing paren is present.
-func parseArgNumber(format string) (index int, wid int, ok bool) {
-	// There must be at least 3 bytes: [n].
-	if len(format) < 3 {
-		return 0, 1, false
-	}
-
-	// Find closing bracket.
-	for i := 1; i < len(format); i++ {
-		if format[i] == ']' {
-			width, ok, newi := parsenum(format, 1, i)
-			if !ok || newi != i {
-				return 0, i + 1, false
-			}
-			return width - 1, i + 1, true // arg numbers are one-indexed and skip paren.
-		}
-	}
-	return 0, 1, false
-}
-
-// argNumber returns the next argument to evaluate, which is either the value of the passed-in
-// argNum or the value of the bracketed integer that begins format[i:]. It also returns
-// the new value of i, that is, the index of the next byte of the format to process.
-func (p *pp) argNumber(argNum int, format string, i int, numArgs int) (newArgNum, newi int, found bool) {
-	if len(format) <= i || format[i] != '[' {
-		return argNum, i, false
-	}
-	p.reordered = true
-	index, wid, ok := parseArgNumber(format[i:])
-	if ok && 0 <= index && index < numArgs {
-		return index, i + wid, true
-	}
-	p.goodArgNum = false
-	return argNum, i + wid, ok
-}
-
-func (p *pp) badArgNum(verb rune) {
-	p.buf.writeString(percentBangString)
-	p.buf.writeRune(verb)
-	p.buf.writeString(badIndexString)
-}
-
-func (p *pp) missingArg(verb rune) {
-	p.buf.writeString(percentBangString)
-	p.buf.writeRune(verb)
-	p.buf.writeString(missingString)
-}
-
-func (p *pp) doPrintf(format string, a []any) {
-	end := len(format)
-	argNum := 0         // we process one argument per non-trivial format
-	afterIndex := false // previous item in format was an index like [3].
-	p.reordered = false
-formatLoop:
-	for i := 0; i < end; {
-		p.goodArgNum = true
-		lasti := i
-		for i < end && format[i] != '%' {
-			i++
-		}
-		if i > lasti {
-			p.buf.writeString(format[lasti:i])
-		}
-		if i >= end {
-			// done processing format string
-			break
-		}
-
-		// Process one verb
-		i++
-
-		// Do we have flags?
-		p.fmt.clearflags()
-	simpleFormat:
-		for ; i < end; i++ {
-			c := format[i]
-			switch c {
-			case '#':
-				p.fmt.sharp = true
-			case '0':
-				p.fmt.zero = !p.fmt.minus // Only allow zero padding to the left.
-			case '+':
-				p.fmt.plus = true
-			case '-':
-				p.fmt.minus = true
-				p.fmt.zero = false // Do not pad with zeros to the right.
-			case ' ':
-				p.fmt.space = true
-			default:
-				// Fast path for common case of ascii lower case simple verbs
-				// without precision or width or argument indices.
-				if 'a' <= c && c <= 'z' && argNum < len(a) {
-					if c == 'v' {
-						// Go syntax
-						p.fmt.sharpV = p.fmt.sharp
-						p.fmt.sharp = false
-						// Struct-field syntax
-						p.fmt.plusV = p.fmt.plus
-						p.fmt.plus = false
-					}
-					p.printArg(a[argNum], rune(c))
-					argNum++
-					i++
-					continue formatLoop
-				}
-				// Format is more complex than simple flags and a verb or is malformed.
-				break simpleFormat
-			}
-		}
-
-		// Do we have an explicit argument index?
-		argNum, i, afterIndex = p.argNumber(argNum, format, i, len(a))
-
-		// Do we have width?
-		if i < end && format[i] == '*' {
-			i++
-			p.fmt.wid, p.fmt.widPresent, argNum = intFromArg(a, argNum)
-
-			if !p.fmt.widPresent {
-				p.buf.writeString(badWidthString)
-			}
-
-			// We have a negative width, so take its value and ensure
-			// that the minus flag is set
-			if p.fmt.wid < 0 {
-				p.fmt.wid = -p.fmt.wid
-				p.fmt.minus = true
-				p.fmt.zero = false // Do not pad with zeros to the right.
-			}
-			afterIndex = false
-		} else {
-			p.fmt.wid, p.fmt.widPresent, i = parsenum(format, i, end)
-			if afterIndex && p.fmt.widPresent { // "%[3]2d"
-				p.goodArgNum = false
-			}
-		}
-
-		// Do we have precision?
-		if i+1 < end && format[i] == '.' {
-			i++
-			if afterIndex { // "%[3].2d"
-				p.goodArgNum = false
-			}
-			argNum, i, afterIndex = p.argNumber(argNum, format, i, len(a))
-			if i < end && format[i] == '*' {
-				i++
-				p.fmt.prec, p.fmt.precPresent, argNum = intFromArg(a, argNum)
-				// Negative precision arguments don't make sense
-				if p.fmt.prec < 0 {
-					p.fmt.prec = 0
-					p.fmt.precPresent = false
-				}
-				if !p.fmt.precPresent {
-					p.buf.writeString(badPrecString)
-				}
-				afterIndex = false
-			} else {
-				p.fmt.prec, p.fmt.precPresent, i = parsenum(format, i, end)
-				if !p.fmt.precPresent {
-					p.fmt.prec = 0
-					p.fmt.precPresent = true
-				}
-			}
-		}
-
-		if !afterIndex {
-			argNum, i, afterIndex = p.argNumber(argNum, format, i, len(a))
-		}
-
-		if i >= end {
-			p.buf.writeString(noVerbString)
-			break
-		}
-
-		verb, size := rune(format[i]), 1
-		if verb >= utf8.RuneSelf {
-			verb, size = utf8.DecodeRuneInString(format[i:])
-		}
-		i += size
-
-		switch {
-		case verb == '%': // Percent does not absorb operands and ignores f.wid and f.prec.
-			p.buf.writeByte('%')
-		case !p.goodArgNum:
-			p.badArgNum(verb)
-		case argNum >= len(a): // No argument left over to print for the current verb.
-			p.missingArg(verb)
-		case verb == 'v':
-			// Go syntax
-			p.fmt.sharpV = p.fmt.sharp
-			p.fmt.sharp = false
-			// Struct-field syntax
-			p.fmt.plusV = p.fmt.plus
-			p.fmt.plus = false
-			fallthrough
-		default:
-			p.printArg(a[argNum], verb)
-			argNum++
-		}
-	}
-
-	// Check for extra arguments unless the call accessed the arguments
-	// out of order, in which case it's too expensive to detect if they've all
-	// been used and arguably OK if they're not.
-	if !p.reordered && argNum < len(a) {
-		p.fmt.clearflags()
-		p.buf.writeString(extraString)
-		for i, arg := range a[argNum:] {
-			if i > 0 {
-				p.buf.writeString(commaSpaceString)
-			}
-			if arg == nil {
-				p.buf.writeString(nilAngleString)
-			} else {
-				p.buf.writeString(reflect.TypeOf(arg).String())
-				p.buf.writeByte('=')
-				p.printArg(arg, 'v')
-			}
-		}
-		p.buf.writeByte(')')
-	}
-}
-
-func (p *pp) doPrint(a []any) {
-	prevString := false
-	for argNum, arg := range a {
-		isString := arg != nil && reflect.TypeOf(arg).Kind() == reflect.String
-		// Add a space between two non-string arguments.
-		if argNum > 0 && !isString && !prevString {
-			p.buf.writeByte(' ')
-		}
-		p.printArg(arg, 'v')
-		prevString = isString
-	}
-}
-
-// doPrintln is like doPrint but always adds a space between arguments
-// and a newline after the last argument.
-func (p *pp) doPrintln(a []any) {
-	for argNum, arg := range a {
-		if argNum > 0 {
-			p.buf.writeByte(' ')
-		}
-		p.printArg(arg, 'v')
-	}
-	p.buf.writeByte('\n')
-}
diff --git a/contrib/go/_std_1.18/src/hash/crc32/crc32_amd64.go b/contrib/go/_std_1.18/src/hash/crc32/crc32_amd64.go
deleted file mode 100644
index 7017a89304..0000000000
--- a/contrib/go/_std_1.18/src/hash/crc32/crc32_amd64.go
+++ /dev/null
@@ -1,222 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// AMD64-specific hardware-assisted CRC32 algorithms. See crc32.go for a
-// description of the interface that each architecture-specific file
-// implements.
-
-package crc32
-
-import (
-	"internal/cpu"
-	"unsafe"
-)
-
-// This file contains the code to call the SSE 4.2 version of the Castagnoli
-// and IEEE CRC.
-
-// castagnoliSSE42 is defined in crc32_amd64.s and uses the SSE 4.2 CRC32
-// instruction.
-//go:noescape
-func castagnoliSSE42(crc uint32, p []byte) uint32
-
-// castagnoliSSE42Triple is defined in crc32_amd64.s and uses the SSE 4.2 CRC32
-// instruction.
-//go:noescape
-func castagnoliSSE42Triple(
-	crcA, crcB, crcC uint32,
-	a, b, c []byte,
-	rounds uint32,
-) (retA uint32, retB uint32, retC uint32)
-
-// ieeeCLMUL is defined in crc_amd64.s and uses the PCLMULQDQ
-// instruction as well as SSE 4.1.
-//go:noescape
-func ieeeCLMUL(crc uint32, p []byte) uint32
-
-const castagnoliK1 = 168
-const castagnoliK2 = 1344
-
-type sse42Table [4]Table
-
-var castagnoliSSE42TableK1 *sse42Table
-var castagnoliSSE42TableK2 *sse42Table
-
-func archAvailableCastagnoli() bool {
-	return cpu.X86.HasSSE42
-}
-
-func archInitCastagnoli() {
-	if !cpu.X86.HasSSE42 {
-		panic("arch-specific Castagnoli not available")
-	}
-	castagnoliSSE42TableK1 = new(sse42Table)
-	castagnoliSSE42TableK2 = new(sse42Table)
-	// See description in updateCastagnoli.
-	//    t[0][i] = CRC(i000, O)
-	//    t[1][i] = CRC(0i00, O)
-	//    t[2][i] = CRC(00i0, O)
-	//    t[3][i] = CRC(000i, O)
-	// where O is a sequence of K zeros.
-	var tmp [castagnoliK2]byte
-	for b := 0; b < 4; b++ {
-		for i := 0; i < 256; i++ {
-			val := uint32(i) << uint32(b*8)
-			castagnoliSSE42TableK1[b][i] = castagnoliSSE42(val, tmp[:castagnoliK1])
-			castagnoliSSE42TableK2[b][i] = castagnoliSSE42(val, tmp[:])
-		}
-	}
-}
-
-// castagnoliShift computes the CRC32-C of K1 or K2 zeroes (depending on the
-// table given) with the given initial crc value. This corresponds to
-// CRC(crc, O) in the description in updateCastagnoli.
-func castagnoliShift(table *sse42Table, crc uint32) uint32 {
-	return table[3][crc>>24] ^
-		table[2][(crc>>16)&0xFF] ^
-		table[1][(crc>>8)&0xFF] ^
-		table[0][crc&0xFF]
-}
-
-func archUpdateCastagnoli(crc uint32, p []byte) uint32 {
-	if !cpu.X86.HasSSE42 {
-		panic("not available")
-	}
-
-	// This method is inspired from the algorithm in Intel's white paper:
-	//    "Fast CRC Computation for iSCSI Polynomial Using CRC32 Instruction"
-	// The same strategy of splitting the buffer in three is used but the
-	// combining calculation is different; the complete derivation is explained
-	// below.
-	//
-	// -- The basic idea --
-	//
-	// The CRC32 instruction (available in SSE4.2) can process 8 bytes at a
-	// time. In recent Intel architectures the instruction takes 3 cycles;
-	// however the processor can pipeline up to three instructions if they
-	// don't depend on each other.
-	//
-	// Roughly this means that we can process three buffers in about the same
-	// time we can process one buffer.
-	//
-	// The idea is then to split the buffer in three, CRC the three pieces
-	// separately and then combine the results.
-	//
-	// Combining the results requires precomputed tables, so we must choose a
-	// fixed buffer length to optimize. The longer the length, the faster; but
-	// only buffers longer than this length will use the optimization. We choose
-	// two cutoffs and compute tables for both:
-	//  - one around 512: 168*3=504
-	//  - one around 4KB: 1344*3=4032
-	//
-	// -- The nitty gritty --
-	//
-	// Let CRC(I, X) be the non-inverted CRC32-C of the sequence X (with
-	// initial non-inverted CRC I). This function has the following properties:
-	//   (a) CRC(I, AB) = CRC(CRC(I, A), B)
-	//   (b) CRC(I, A xor B) = CRC(I, A) xor CRC(0, B)
-	//
-	// Say we want to compute CRC(I, ABC) where A, B, C are three sequences of
-	// K bytes each, where K is a fixed constant. Let O be the sequence of K zero
-	// bytes.
-	//
-	// CRC(I, ABC) = CRC(I, ABO xor C)
-	//             = CRC(I, ABO) xor CRC(0, C)
-	//             = CRC(CRC(I, AB), O) xor CRC(0, C)
-	//             = CRC(CRC(I, AO xor B), O) xor CRC(0, C)
-	//             = CRC(CRC(I, AO) xor CRC(0, B), O) xor CRC(0, C)
-	//             = CRC(CRC(CRC(I, A), O) xor CRC(0, B), O) xor CRC(0, C)
-	//
-	// The castagnoliSSE42Triple function can compute CRC(I, A), CRC(0, B),
-	// and CRC(0, C) efficiently.  We just need to find a way to quickly compute
-	// CRC(uvwx, O) given a 4-byte initial value uvwx. We can precompute these
-	// values; since we can't have a 32-bit table, we break it up into four
-	// 8-bit tables:
-	//
-	//    CRC(uvwx, O) = CRC(u000, O) xor
-	//                   CRC(0v00, O) xor
-	//                   CRC(00w0, O) xor
-	//                   CRC(000x, O)
-	//
-	// We can compute tables corresponding to the four terms for all 8-bit
-	// values.
-
-	crc = ^crc
-
-	// If a buffer is long enough to use the optimization, process the first few
-	// bytes to align the buffer to an 8 byte boundary (if necessary).
-	if len(p) >= castagnoliK1*3 {
-		delta := int(uintptr(unsafe.Pointer(&p[0])) & 7)
-		if delta != 0 {
-			delta = 8 - delta
-			crc = castagnoliSSE42(crc, p[:delta])
-			p = p[delta:]
-		}
-	}
-
-	// Process 3*K2 at a time.
-	for len(p) >= castagnoliK2*3 {
-		// Compute CRC(I, A), CRC(0, B), and CRC(0, C).
-		crcA, crcB, crcC := castagnoliSSE42Triple(
-			crc, 0, 0,
-			p, p[castagnoliK2:], p[castagnoliK2*2:],
-			castagnoliK2/24)
-
-		// CRC(I, AB) = CRC(CRC(I, A), O) xor CRC(0, B)
-		crcAB := castagnoliShift(castagnoliSSE42TableK2, crcA) ^ crcB
-		// CRC(I, ABC) = CRC(CRC(I, AB), O) xor CRC(0, C)
-		crc = castagnoliShift(castagnoliSSE42TableK2, crcAB) ^ crcC
-		p = p[castagnoliK2*3:]
-	}
-
-	// Process 3*K1 at a time.
-	for len(p) >= castagnoliK1*3 {
-		// Compute CRC(I, A), CRC(0, B), and CRC(0, C).
-		crcA, crcB, crcC := castagnoliSSE42Triple(
-			crc, 0, 0,
-			p, p[castagnoliK1:], p[castagnoliK1*2:],
-			castagnoliK1/24)
-
-		// CRC(I, AB) = CRC(CRC(I, A), O) xor CRC(0, B)
-		crcAB := castagnoliShift(castagnoliSSE42TableK1, crcA) ^ crcB
-		// CRC(I, ABC) = CRC(CRC(I, AB), O) xor CRC(0, C)
-		crc = castagnoliShift(castagnoliSSE42TableK1, crcAB) ^ crcC
-		p = p[castagnoliK1*3:]
-	}
-
-	// Use the simple implementation for what's left.
-	crc = castagnoliSSE42(crc, p)
-	return ^crc
-}
-
-func archAvailableIEEE() bool {
-	return cpu.X86.HasPCLMULQDQ && cpu.X86.HasSSE41
-}
-
-var archIeeeTable8 *slicing8Table
-
-func archInitIEEE() {
-	if !cpu.X86.HasPCLMULQDQ || !cpu.X86.HasSSE41 {
-		panic("not available")
-	}
-	// We still use slicing-by-8 for small buffers.
-	archIeeeTable8 = slicingMakeTable(IEEE)
-}
-
-func archUpdateIEEE(crc uint32, p []byte) uint32 {
-	if !cpu.X86.HasPCLMULQDQ || !cpu.X86.HasSSE41 {
-		panic("not available")
-	}
-
-	if len(p) >= 64 {
-		left := len(p) & 15
-		do := len(p) - left
-		crc = ^ieeeCLMUL(^crc, p[:do])
-		p = p[do:]
-	}
-	if len(p) == 0 {
-		return crc
-	}
-	return slicingUpdate(crc, archIeeeTable8, p)
-}
diff --git a/contrib/go/_std_1.18/src/internal/bytealg/compare_native.go b/contrib/go/_std_1.18/src/internal/bytealg/compare_native.go
deleted file mode 100644
index 21ff8fe786..0000000000
--- a/contrib/go/_std_1.18/src/internal/bytealg/compare_native.go
+++ /dev/null
@@ -1,19 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build 386 || amd64 || s390x || arm || arm64 || ppc64 || ppc64le || mips || mipsle || wasm || mips64 || mips64le
-
-package bytealg
-
-import _ "unsafe" // For go:linkname
-
-//go:noescape
-func Compare(a, b []byte) int
-
-// The declaration below generates ABI wrappers for functions
-// implemented in assembly in this package but declared in another
-// package.
-
-//go:linkname abigen_runtime_cmpstring runtime.cmpstring
-func abigen_runtime_cmpstring(a, b string) int
diff --git a/contrib/go/_std_1.18/src/internal/bytealg/indexbyte_native.go b/contrib/go/_std_1.18/src/internal/bytealg/indexbyte_native.go
deleted file mode 100644
index 2101021e2d..0000000000
--- a/contrib/go/_std_1.18/src/internal/bytealg/indexbyte_native.go
+++ /dev/null
@@ -1,13 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build 386 || amd64 || s390x || arm || arm64 || ppc64 || ppc64le || mips || mipsle || mips64 || mips64le || riscv64 || wasm
-
-package bytealg
-
-//go:noescape
-func IndexByte(b []byte, c byte) int
-
-//go:noescape
-func IndexByteString(s string, c byte) int
diff --git a/contrib/go/_std_1.18/src/internal/cpu/cpu.go b/contrib/go/_std_1.18/src/internal/cpu/cpu.go
deleted file mode 100644
index 30745344e1..0000000000
--- a/contrib/go/_std_1.18/src/internal/cpu/cpu.go
+++ /dev/null
@@ -1,220 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package cpu implements processor feature detection
-// used by the Go standard library.
-package cpu
-
-// DebugOptions is set to true by the runtime if the OS supports reading
-// GODEBUG early in runtime startup.
-// This should not be changed after it is initialized.
-var DebugOptions bool
-
-// CacheLinePad is used to pad structs to avoid false sharing.
-type CacheLinePad struct{ _ [CacheLinePadSize]byte }
-
-// CacheLineSize is the CPU's assumed cache line size.
-// There is currently no runtime detection of the real cache line size
-// so we use the constant per GOARCH CacheLinePadSize as an approximation.
-var CacheLineSize uintptr = CacheLinePadSize
-
-// The booleans in X86 contain the correspondingly named cpuid feature bit.
-// HasAVX and HasAVX2 are only set if the OS does support XMM and YMM registers
-// in addition to the cpuid feature bit being set.
-// The struct is padded to avoid false sharing.
-var X86 struct {
-	_            CacheLinePad
-	HasAES       bool
-	HasADX       bool
-	HasAVX       bool
-	HasAVX2      bool
-	HasBMI1      bool
-	HasBMI2      bool
-	HasERMS      bool
-	HasFMA       bool
-	HasOSXSAVE   bool
-	HasPCLMULQDQ bool
-	HasPOPCNT    bool
-	HasRDTSCP    bool
-	HasSSE3      bool
-	HasSSSE3     bool
-	HasSSE41     bool
-	HasSSE42     bool
-	_            CacheLinePad
-}
-
-// The booleans in ARM contain the correspondingly named cpu feature bit.
-// The struct is padded to avoid false sharing.
-var ARM struct {
-	_        CacheLinePad
-	HasVFPv4 bool
-	HasIDIVA bool
-	_        CacheLinePad
-}
-
-// The booleans in ARM64 contain the correspondingly named cpu feature bit.
-// The struct is padded to avoid false sharing.
-var ARM64 struct {
-	_            CacheLinePad
-	HasAES       bool
-	HasPMULL     bool
-	HasSHA1      bool
-	HasSHA2      bool
-	HasCRC32     bool
-	HasATOMICS   bool
-	HasCPUID     bool
-	IsNeoverseN1 bool
-	IsZeus       bool
-	_            CacheLinePad
-}
-
-var MIPS64X struct {
-	_      CacheLinePad
-	HasMSA bool // MIPS SIMD architecture
-	_      CacheLinePad
-}
-
-// For ppc64(le), it is safe to check only for ISA level starting on ISA v3.00,
-// since there are no optional categories. There are some exceptions that also
-// require kernel support to work (darn, scv), so there are feature bits for
-// those as well. The minimum processor requirement is POWER8 (ISA 2.07).
-// The struct is padded to avoid false sharing.
-var PPC64 struct {
-	_        CacheLinePad
-	HasDARN  bool // Hardware random number generator (requires kernel enablement)
-	HasSCV   bool // Syscall vectored (requires kernel enablement)
-	IsPOWER8 bool // ISA v2.07 (POWER8)
-	IsPOWER9 bool // ISA v3.00 (POWER9)
-	_        CacheLinePad
-}
-
-var S390X struct {
-	_         CacheLinePad
-	HasZARCH  bool // z architecture mode is active [mandatory]
-	HasSTFLE  bool // store facility list extended [mandatory]
-	HasLDISP  bool // long (20-bit) displacements [mandatory]
-	HasEIMM   bool // 32-bit immediates [mandatory]
-	HasDFP    bool // decimal floating point
-	HasETF3EH bool // ETF-3 enhanced
-	HasMSA    bool // message security assist (CPACF)
-	HasAES    bool // KM-AES{128,192,256} functions
-	HasAESCBC bool // KMC-AES{128,192,256} functions
-	HasAESCTR bool // KMCTR-AES{128,192,256} functions
-	HasAESGCM bool // KMA-GCM-AES{128,192,256} functions
-	HasGHASH  bool // KIMD-GHASH function
-	HasSHA1   bool // K{I,L}MD-SHA-1 functions
-	HasSHA256 bool // K{I,L}MD-SHA-256 functions
-	HasSHA512 bool // K{I,L}MD-SHA-512 functions
-	HasSHA3   bool // K{I,L}MD-SHA3-{224,256,384,512} and K{I,L}MD-SHAKE-{128,256} functions
-	HasVX     bool // vector facility. Note: the runtime sets this when it processes auxv records.
-	HasVXE    bool // vector-enhancements facility 1
-	HasKDSA   bool // elliptic curve functions
-	HasECDSA  bool // NIST curves
-	HasEDDSA  bool // Edwards curves
-	_         CacheLinePad
-}
-
-// Initialize examines the processor and sets the relevant variables above.
-// This is called by the runtime package early in program initialization,
-// before normal init functions are run. env is set by runtime if the OS supports
-// cpu feature options in GODEBUG.
-func Initialize(env string) {
-	doinit()
-	processOptions(env)
-}
-
-// options contains the cpu debug options that can be used in GODEBUG.
-// Options are arch dependent and are added by the arch specific doinit functions.
-// Features that are mandatory for the specific GOARCH should not be added to options
-// (e.g. SSE2 on amd64).
-var options []option
-
-// Option names should be lower case. e.g. avx instead of AVX.
-type option struct {
-	Name      string
-	Feature   *bool
-	Specified bool // whether feature value was specified in GODEBUG
-	Enable    bool // whether feature should be enabled
-}
-
-// processOptions enables or disables CPU feature values based on the parsed env string.
-// The env string is expected to be of the form cpu.feature1=value1,cpu.feature2=value2...
-// where feature names is one of the architecture specific list stored in the
-// cpu packages options variable and values are either 'on' or 'off'.
-// If env contains cpu.all=off then all cpu features referenced through the options
-// variable are disabled. Other feature names and values result in warning messages.
-func processOptions(env string) {
-field:
-	for env != "" {
-		field := ""
-		i := indexByte(env, ',')
-		if i < 0 {
-			field, env = env, ""
-		} else {
-			field, env = env[:i], env[i+1:]
-		}
-		if len(field) < 4 || field[:4] != "cpu." {
-			continue
-		}
-		i = indexByte(field, '=')
-		if i < 0 {
-			print("GODEBUG: no value specified for \"", field, "\"\n")
-			continue
-		}
-		key, value := field[4:i], field[i+1:] // e.g. "SSE2", "on"
-
-		var enable bool
-		switch value {
-		case "on":
-			enable = true
-		case "off":
-			enable = false
-		default:
-			print("GODEBUG: value \"", value, "\" not supported for cpu option \"", key, "\"\n")
-			continue field
-		}
-
-		if key == "all" {
-			for i := range options {
-				options[i].Specified = true
-				options[i].Enable = enable
-			}
-			continue field
-		}
-
-		for i := range options {
-			if options[i].Name == key {
-				options[i].Specified = true
-				options[i].Enable = enable
-				continue field
-			}
-		}
-
-		print("GODEBUG: unknown cpu feature \"", key, "\"\n")
-	}
-
-	for _, o := range options {
-		if !o.Specified {
-			continue
-		}
-
-		if o.Enable && !*o.Feature {
-			print("GODEBUG: can not enable \"", o.Name, "\", missing CPU support\n")
-			continue
-		}
-
-		*o.Feature = o.Enable
-	}
-}
-
-// indexByte returns the index of the first instance of c in s,
-// or -1 if c is not present in s.
-func indexByte(s string, c byte) int {
-	for i := 0; i < len(s); i++ {
-		if s[i] == c {
-			return i
-		}
-	}
-	return -1
-}
diff --git a/contrib/go/_std_1.18/src/internal/cpu/cpu_x86.go b/contrib/go/_std_1.18/src/internal/cpu/cpu_x86.go
deleted file mode 100644
index 81d5ceed61..0000000000
--- a/contrib/go/_std_1.18/src/internal/cpu/cpu_x86.go
+++ /dev/null
@@ -1,173 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build 386 || amd64
-
-package cpu
-
-const CacheLinePadSize = 64
-
-// cpuid is implemented in cpu_x86.s.
-func cpuid(eaxArg, ecxArg uint32) (eax, ebx, ecx, edx uint32)
-
-// xgetbv with ecx = 0 is implemented in cpu_x86.s.
-func xgetbv() (eax, edx uint32)
-
-const (
-	// edx bits
-	cpuid_SSE2 = 1 << 26
-
-	// ecx bits
-	cpuid_SSE3      = 1 << 0
-	cpuid_PCLMULQDQ = 1 << 1
-	cpuid_SSSE3     = 1 << 9
-	cpuid_FMA       = 1 << 12
-	cpuid_SSE41     = 1 << 19
-	cpuid_SSE42     = 1 << 20
-	cpuid_POPCNT    = 1 << 23
-	cpuid_AES       = 1 << 25
-	cpuid_OSXSAVE   = 1 << 27
-	cpuid_AVX       = 1 << 28
-
-	// ebx bits
-	cpuid_BMI1 = 1 << 3
-	cpuid_AVX2 = 1 << 5
-	cpuid_BMI2 = 1 << 8
-	cpuid_ERMS = 1 << 9
-	cpuid_ADX  = 1 << 19
-
-	// edx bits for CPUID 0x80000001
-	cpuid_RDTSCP = 1 << 27
-)
-
-var maxExtendedFunctionInformation uint32
-
-func doinit() {
-	options = []option{
-		{Name: "adx", Feature: &X86.HasADX},
-		{Name: "aes", Feature: &X86.HasAES},
-		{Name: "avx", Feature: &X86.HasAVX},
-		{Name: "avx2", Feature: &X86.HasAVX2},
-		{Name: "bmi1", Feature: &X86.HasBMI1},
-		{Name: "bmi2", Feature: &X86.HasBMI2},
-		{Name: "erms", Feature: &X86.HasERMS},
-		{Name: "fma", Feature: &X86.HasFMA},
-		{Name: "pclmulqdq", Feature: &X86.HasPCLMULQDQ},
-		{Name: "popcnt", Feature: &X86.HasPOPCNT},
-		{Name: "rdtscp", Feature: &X86.HasRDTSCP},
-		{Name: "sse3", Feature: &X86.HasSSE3},
-		{Name: "sse41", Feature: &X86.HasSSE41},
-		{Name: "sse42", Feature: &X86.HasSSE42},
-		{Name: "ssse3", Feature: &X86.HasSSSE3},
-	}
-
-	maxID, _, _, _ := cpuid(0, 0)
-
-	if maxID < 1 {
-		return
-	}
-
-	maxExtendedFunctionInformation, _, _, _ = cpuid(0x80000000, 0)
-
-	_, _, ecx1, _ := cpuid(1, 0)
-
-	X86.HasSSE3 = isSet(ecx1, cpuid_SSE3)
-	X86.HasPCLMULQDQ = isSet(ecx1, cpuid_PCLMULQDQ)
-	X86.HasSSSE3 = isSet(ecx1, cpuid_SSSE3)
-	X86.HasSSE41 = isSet(ecx1, cpuid_SSE41)
-	X86.HasSSE42 = isSet(ecx1, cpuid_SSE42)
-	X86.HasPOPCNT = isSet(ecx1, cpuid_POPCNT)
-	X86.HasAES = isSet(ecx1, cpuid_AES)
-
-	// OSXSAVE can be false when using older Operating Systems
-	// or when explicitly disabled on newer Operating Systems by
-	// e.g. setting the xsavedisable boot option on Windows 10.
-	X86.HasOSXSAVE = isSet(ecx1, cpuid_OSXSAVE)
-
-	// The FMA instruction set extension only has VEX prefixed instructions.
-	// VEX prefixed instructions require OSXSAVE to be enabled.
-	// See Intel 64 and IA-32 Architecture Software Developer’s Manual Volume 2
-	// Section 2.4 "AVX and SSE Instruction Exception Specification"
-	X86.HasFMA = isSet(ecx1, cpuid_FMA) && X86.HasOSXSAVE
-
-	osSupportsAVX := false
-	// For XGETBV, OSXSAVE bit is required and sufficient.
-	if X86.HasOSXSAVE {
-		eax, _ := xgetbv()
-		// Check if XMM and YMM registers have OS support.
-		osSupportsAVX = isSet(eax, 1<<1) && isSet(eax, 1<<2)
-	}
-
-	X86.HasAVX = isSet(ecx1, cpuid_AVX) && osSupportsAVX
-
-	if maxID < 7 {
-		return
-	}
-
-	_, ebx7, _, _ := cpuid(7, 0)
-	X86.HasBMI1 = isSet(ebx7, cpuid_BMI1)
-	X86.HasAVX2 = isSet(ebx7, cpuid_AVX2) && osSupportsAVX
-	X86.HasBMI2 = isSet(ebx7, cpuid_BMI2)
-	X86.HasERMS = isSet(ebx7, cpuid_ERMS)
-	X86.HasADX = isSet(ebx7, cpuid_ADX)
-
-	var maxExtendedInformation uint32
-	maxExtendedInformation, _, _, _ = cpuid(0x80000000, 0)
-
-	if maxExtendedInformation < 0x80000001 {
-		return
-	}
-
-	_, _, _, edxExt1 := cpuid(0x80000001, 0)
-	X86.HasRDTSCP = isSet(edxExt1, cpuid_RDTSCP)
-}
-
-func isSet(hwc uint32, value uint32) bool {
-	return hwc&value != 0
-}
-
-// Name returns the CPU name given by the vendor.
-// If the CPU name can not be determined an
-// empty string is returned.
-func Name() string {
-	if maxExtendedFunctionInformation < 0x80000004 {
-		return ""
-	}
-
-	data := make([]byte, 0, 3*4*4)
-
-	var eax, ebx, ecx, edx uint32
-	eax, ebx, ecx, edx = cpuid(0x80000002, 0)
-	data = appendBytes(data, eax, ebx, ecx, edx)
-	eax, ebx, ecx, edx = cpuid(0x80000003, 0)
-	data = appendBytes(data, eax, ebx, ecx, edx)
-	eax, ebx, ecx, edx = cpuid(0x80000004, 0)
-	data = appendBytes(data, eax, ebx, ecx, edx)
-
-	// Trim leading spaces.
-	for len(data) > 0 && data[0] == ' ' {
-		data = data[1:]
-	}
-
-	// Trim tail after and including the first null byte.
-	for i, c := range data {
-		if c == '\x00' {
-			data = data[:i]
-			break
-		}
-	}
-
-	return string(data)
-}
-
-func appendBytes(b []byte, args ...uint32) []byte {
-	for _, arg := range args {
-		b = append(b,
-			byte((arg >> 0)),
-			byte((arg >> 8)),
-			byte((arg >> 16)),
-			byte((arg >> 24)))
-	}
-	return b
-}
diff --git a/contrib/go/_std_1.18/src/internal/cpu/cpu_x86.s b/contrib/go/_std_1.18/src/internal/cpu/cpu_x86.s
deleted file mode 100644
index edef21905c..0000000000
--- a/contrib/go/_std_1.18/src/internal/cpu/cpu_x86.s
+++ /dev/null
@@ -1,26 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build 386 || amd64
-
-#include "textflag.h"
-
-// func cpuid(eaxArg, ecxArg uint32) (eax, ebx, ecx, edx uint32)
-TEXT ·cpuid(SB), NOSPLIT, $0-24
-	MOVL eaxArg+0(FP), AX
-	MOVL ecxArg+4(FP), CX
-	CPUID
-	MOVL AX, eax+8(FP)
-	MOVL BX, ebx+12(FP)
-	MOVL CX, ecx+16(FP)
-	MOVL DX, edx+20(FP)
-	RET
-
-// func xgetbv() (eax, edx uint32)
-TEXT ·xgetbv(SB),NOSPLIT,$0-8
-	MOVL $0, CX
-	XGETBV
-	MOVL AX, eax+0(FP)
-	MOVL DX, edx+4(FP)
-	RET
diff --git a/contrib/go/_std_1.18/src/internal/fmtsort/sort.go b/contrib/go/_std_1.18/src/internal/fmtsort/sort.go
deleted file mode 100644
index 34c1f477f0..0000000000
--- a/contrib/go/_std_1.18/src/internal/fmtsort/sort.go
+++ /dev/null
@@ -1,220 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package fmtsort provides a general stable ordering mechanism
-// for maps, on behalf of the fmt and text/template packages.
-// It is not guaranteed to be efficient and works only for types
-// that are valid map keys.
-package fmtsort
-
-import (
-	"reflect"
-	"sort"
-)
-
-// Note: Throughout this package we avoid calling reflect.Value.Interface as
-// it is not always legal to do so and it's easier to avoid the issue than to face it.
-
-// SortedMap represents a map's keys and values. The keys and values are
-// aligned in index order: Value[i] is the value in the map corresponding to Key[i].
-type SortedMap struct {
-	Key   []reflect.Value
-	Value []reflect.Value
-}
-
-func (o *SortedMap) Len() int           { return len(o.Key) }
-func (o *SortedMap) Less(i, j int) bool { return compare(o.Key[i], o.Key[j]) < 0 }
-func (o *SortedMap) Swap(i, j int) {
-	o.Key[i], o.Key[j] = o.Key[j], o.Key[i]
-	o.Value[i], o.Value[j] = o.Value[j], o.Value[i]
-}
-
-// Sort accepts a map and returns a SortedMap that has the same keys and
-// values but in a stable sorted order according to the keys, modulo issues
-// raised by unorderable key values such as NaNs.
-//
-// The ordering rules are more general than with Go's < operator:
-//
-//  - when applicable, nil compares low
-//  - ints, floats, and strings order by <
-//  - NaN compares less than non-NaN floats
-//  - bool compares false before true
-//  - complex compares real, then imag
-//  - pointers compare by machine address
-//  - channel values compare by machine address
-//  - structs compare each field in turn
-//  - arrays compare each element in turn.
-//    Otherwise identical arrays compare by length.
-//  - interface values compare first by reflect.Type describing the concrete type
-//    and then by concrete value as described in the previous rules.
-//
-func Sort(mapValue reflect.Value) *SortedMap {
-	if mapValue.Type().Kind() != reflect.Map {
-		return nil
-	}
-	// Note: this code is arranged to not panic even in the presence
-	// of a concurrent map update. The runtime is responsible for
-	// yelling loudly if that happens. See issue 33275.
-	n := mapValue.Len()
-	key := make([]reflect.Value, 0, n)
-	value := make([]reflect.Value, 0, n)
-	iter := mapValue.MapRange()
-	for iter.Next() {
-		key = append(key, iter.Key())
-		value = append(value, iter.Value())
-	}
-	sorted := &SortedMap{
-		Key:   key,
-		Value: value,
-	}
-	sort.Stable(sorted)
-	return sorted
-}
-
-// compare compares two values of the same type. It returns -1, 0, 1
-// according to whether a > b (1), a == b (0), or a < b (-1).
-// If the types differ, it returns -1.
-// See the comment on Sort for the comparison rules.
-func compare(aVal, bVal reflect.Value) int {
-	aType, bType := aVal.Type(), bVal.Type()
-	if aType != bType {
-		return -1 // No good answer possible, but don't return 0: they're not equal.
-	}
-	switch aVal.Kind() {
-	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
-		a, b := aVal.Int(), bVal.Int()
-		switch {
-		case a < b:
-			return -1
-		case a > b:
-			return 1
-		default:
-			return 0
-		}
-	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
-		a, b := aVal.Uint(), bVal.Uint()
-		switch {
-		case a < b:
-			return -1
-		case a > b:
-			return 1
-		default:
-			return 0
-		}
-	case reflect.String:
-		a, b := aVal.String(), bVal.String()
-		switch {
-		case a < b:
-			return -1
-		case a > b:
-			return 1
-		default:
-			return 0
-		}
-	case reflect.Float32, reflect.Float64:
-		return floatCompare(aVal.Float(), bVal.Float())
-	case reflect.Complex64, reflect.Complex128:
-		a, b := aVal.Complex(), bVal.Complex()
-		if c := floatCompare(real(a), real(b)); c != 0 {
-			return c
-		}
-		return floatCompare(imag(a), imag(b))
-	case reflect.Bool:
-		a, b := aVal.Bool(), bVal.Bool()
-		switch {
-		case a == b:
-			return 0
-		case a:
-			return 1
-		default:
-			return -1
-		}
-	case reflect.Pointer, reflect.UnsafePointer:
-		a, b := aVal.Pointer(), bVal.Pointer()
-		switch {
-		case a < b:
-			return -1
-		case a > b:
-			return 1
-		default:
-			return 0
-		}
-	case reflect.Chan:
-		if c, ok := nilCompare(aVal, bVal); ok {
-			return c
-		}
-		ap, bp := aVal.Pointer(), bVal.Pointer()
-		switch {
-		case ap < bp:
-			return -1
-		case ap > bp:
-			return 1
-		default:
-			return 0
-		}
-	case reflect.Struct:
-		for i := 0; i < aVal.NumField(); i++ {
-			if c := compare(aVal.Field(i), bVal.Field(i)); c != 0 {
-				return c
-			}
-		}
-		return 0
-	case reflect.Array:
-		for i := 0; i < aVal.Len(); i++ {
-			if c := compare(aVal.Index(i), bVal.Index(i)); c != 0 {
-				return c
-			}
-		}
-		return 0
-	case reflect.Interface:
-		if c, ok := nilCompare(aVal, bVal); ok {
-			return c
-		}
-		c := compare(reflect.ValueOf(aVal.Elem().Type()), reflect.ValueOf(bVal.Elem().Type()))
-		if c != 0 {
-			return c
-		}
-		return compare(aVal.Elem(), bVal.Elem())
-	default:
-		// Certain types cannot appear as keys (maps, funcs, slices), but be explicit.
-		panic("bad type in compare: " + aType.String())
-	}
-}
-
-// nilCompare checks whether either value is nil. If not, the boolean is false.
-// If either value is nil, the boolean is true and the integer is the comparison
-// value. The comparison is defined to be 0 if both are nil, otherwise the one
-// nil value compares low. Both arguments must represent a chan, func,
-// interface, map, pointer, or slice.
-func nilCompare(aVal, bVal reflect.Value) (int, bool) {
-	if aVal.IsNil() {
-		if bVal.IsNil() {
-			return 0, true
-		}
-		return -1, true
-	}
-	if bVal.IsNil() {
-		return 1, true
-	}
-	return 0, false
-}
-
-// floatCompare compares two floating-point values. NaNs compare low.
-func floatCompare(a, b float64) int {
-	switch {
-	case isNaN(a):
-		return -1 // No good answer if b is a NaN so don't bother checking.
-	case isNaN(b):
-		return 1
-	case a < b:
-		return -1
-	case a > b:
-		return 1
-	}
-	return 0
-}
-
-func isNaN(a float64) bool {
-	return a != a
-}
diff --git a/contrib/go/_std_1.18/src/internal/goarch/goarch.go b/contrib/go/_std_1.18/src/internal/goarch/goarch.go
deleted file mode 100644
index 921f5a208f..0000000000
--- a/contrib/go/_std_1.18/src/internal/goarch/goarch.go
+++ /dev/null
@@ -1,58 +0,0 @@
-// Copyright 2021 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// package goarch contains GOARCH-specific constants.
-package goarch
-
-// The next line makes 'go generate' write the zgoarch*.go files with
-// per-arch information, including constants named $GOARCH for every
-// GOARCH. The constant is 1 on the current system, 0 otherwise; multiplying
-// by them is useful for defining GOARCH-specific constants.
-//go:generate go run gengoarch.go
-
-type ArchFamilyType int
-
-const (
-	AMD64 ArchFamilyType = iota
-	ARM
-	ARM64
-	I386
-	MIPS
-	MIPS64
-	PPC64
-	RISCV64
-	S390X
-	WASM
-)
-
-// PtrSize is the size of a pointer in bytes - unsafe.Sizeof(uintptr(0)) but as an ideal constant.
-// It is also the size of the machine's native word size (that is, 4 on 32-bit systems, 8 on 64-bit).
-const PtrSize = 4 << (^uintptr(0) >> 63)
-
-// ArchFamily is the architecture family (AMD64, ARM, ...)
-const ArchFamily ArchFamilyType = _ArchFamily
-
-// BigEndian reports whether the architecture is big-endian.
-const BigEndian = IsArmbe|IsArm64be|IsMips|IsMips64|IsPpc|IsPpc64|IsS390|IsS390x|IsSparc|IsSparc64 == 1
-
-// DefaultPhysPageSize is the default physical page size.
-const DefaultPhysPageSize = _DefaultPhysPageSize
-
-// PCQuantum is the minimal unit for a program counter (1 on x86, 4 on most other systems).
-// The various PC tables record PC deltas pre-divided by PCQuantum.
-const PCQuantum = _PCQuantum
-
-// Int64Align is the required alignment for a 64-bit integer (4 on 32-bit systems, 8 on 64-bit).
-const Int64Align = PtrSize
-
-// MinFrameSize is the size of the system-reserved words at the bottom
-// of a frame (just above the architectural stack pointer).
-// It is zero on x86 and PtrSize on most non-x86 (LR-based) systems.
-// On PowerPC it is larger, to cover three more reserved words:
-// the compiler word, the link editor word, and the TOC save word.
-const MinFrameSize = _MinFrameSize
-
-// StackAlign is the required alignment of the SP register.
-// The stack must be at least word aligned, but some architectures require more.
-const StackAlign = _StackAlign
diff --git a/contrib/go/_std_1.18/src/internal/goexperiment/exp_pacerredesign_on.go b/contrib/go/_std_1.18/src/internal/goexperiment/exp_pacerredesign_on.go
deleted file mode 100644
index b22b031009..0000000000
--- a/contrib/go/_std_1.18/src/internal/goexperiment/exp_pacerredesign_on.go
+++ /dev/null
@@ -1,9 +0,0 @@
-// Code generated by mkconsts.go. DO NOT EDIT.
-
-//go:build goexperiment.pacerredesign
-// +build goexperiment.pacerredesign
-
-package goexperiment
-
-const PacerRedesign = true
-const PacerRedesignInt = 1
diff --git a/contrib/go/_std_1.18/src/internal/goexperiment/exp_regabireflect_on.go b/contrib/go/_std_1.18/src/internal/goexperiment/exp_regabireflect_on.go
deleted file mode 100644
index e8a3e9c06a..0000000000
--- a/contrib/go/_std_1.18/src/internal/goexperiment/exp_regabireflect_on.go
+++ /dev/null
@@ -1,9 +0,0 @@
-// Code generated by mkconsts.go. DO NOT EDIT.
-
-//go:build goexperiment.regabireflect
-// +build goexperiment.regabireflect
-
-package goexperiment
-
-const RegabiReflect = true
-const RegabiReflectInt = 1
diff --git a/contrib/go/_std_1.18/src/internal/goexperiment/flags.go b/contrib/go/_std_1.18/src/internal/goexperiment/flags.go
deleted file mode 100644
index 6d935edc2b..0000000000
--- a/contrib/go/_std_1.18/src/internal/goexperiment/flags.go
+++ /dev/null
@@ -1,99 +0,0 @@
-// Copyright 2021 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package goexperiment implements support for toolchain experiments.
-//
-// Toolchain experiments are controlled by the GOEXPERIMENT
-// environment variable. GOEXPERIMENT is a comma-separated list of
-// experiment names. GOEXPERIMENT can be set at make.bash time, which
-// sets the default experiments for binaries built with the tool
-// chain; or it can be set at build time. GOEXPERIMENT can also be set
-// to "none", which disables any experiments that were enabled at
-// make.bash time.
-//
-// Experiments are exposed to the build in the following ways:
-//
-// - Build tag goexperiment.x is set if experiment x (lower case) is
-// enabled.
-//
-// - For each experiment x (in camel case), this package contains a
-// boolean constant x and an integer constant xInt.
-//
-// - In runtime assembly, the macro GOEXPERIMENT_x is defined if
-// experiment x (lower case) is enabled.
-//
-// In the toolchain, the set of experiments enabled for the current
-// build should be accessed via objabi.Experiment.
-//
-// The set of experiments is included in the output of runtime.Version()
-// and "go version <binary>" if it differs from the default experiments.
-//
-// For the set of experiments supported by the current toolchain, see
-// "go doc goexperiment.Flags".
-//
-// Note that this package defines the set of experiments (in Flags)
-// and records the experiments that were enabled when the package
-// was compiled (as boolean and integer constants).
-//
-// Note especially that this package does not itself change behavior
-// at run time based on the GOEXPERIMENT variable.
-// The code used in builds to interpret the GOEXPERIMENT variable
-// is in the separate package internal/buildcfg.
-package goexperiment
-
-//go:generate go run mkconsts.go
-
-// Flags is the set of experiments that can be enabled or disabled in
-// the current toolchain.
-//
-// When specified in the GOEXPERIMENT environment variable or as build
-// tags, experiments use the strings.ToLower of their field name.
-//
-// For the baseline experimental configuration, see
-// objabi.experimentBaseline.
-//
-// If you change this struct definition, run "go generate".
-type Flags struct {
-	FieldTrack        bool
-	PreemptibleLoops  bool
-	StaticLockRanking bool
-
-	// Unified enables the compiler's unified IR construction
-	// experiment.
-	Unified bool
-
-	// Regabi is split into several sub-experiments that can be
-	// enabled individually. Not all combinations work.
-	// The "regabi" GOEXPERIMENT is an alias for all "working"
-	// subexperiments.
-
-	// RegabiWrappers enables ABI wrappers for calling between
-	// ABI0 and ABIInternal functions. Without this, the ABIs are
-	// assumed to be identical so cross-ABI calls are direct.
-	RegabiWrappers bool
-	// RegabiReflect enables the register-passing paths in
-	// reflection calls. This is also gated by intArgRegs in
-	// reflect and runtime (which are disabled by default) so it
-	// can be used in targeted tests.
-	RegabiReflect bool
-	// RegabiArgs enables register arguments/results in all
-	// compiled Go functions.
-	//
-	// Requires wrappers (to do ABI translation), and reflect (so
-	// reflection calls use registers).
-	RegabiArgs bool
-
-	// PacerRedesign enables the new GC pacer in the runtime.
-	//
-	// Details regarding the new pacer may be found at
-	// https://golang.org/design/44167-gc-pacer-redesign
-	PacerRedesign bool
-
-	// HeapMinimum512KiB reduces the minimum heap size to 512 KiB.
-	//
-	// This was originally reduced as part of PacerRedesign, but
-	// has been broken out to its own experiment that is disabled
-	// by default.
-	HeapMinimum512KiB bool
-}
diff --git a/contrib/go/_std_1.18/src/internal/goos/goos.go b/contrib/go/_std_1.18/src/internal/goos/goos.go
deleted file mode 100644
index ebb521fec6..0000000000
--- a/contrib/go/_std_1.18/src/internal/goos/goos.go
+++ /dev/null
@@ -1,12 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// package goos contains GOOS-specific constants.
-package goos
-
-// The next line makes 'go generate' write the zgoos*.go files with
-// per-OS information, including constants named Is$GOOS for every
-// known GOOS. The constant is 1 on the current system, 0 otherwise;
-// multiplying by them is useful for defining GOOS-specific constants.
-//go:generate go run gengoos.go
diff --git a/contrib/go/_std_1.18/src/internal/intern/intern.go b/contrib/go/_std_1.18/src/internal/intern/intern.go
deleted file mode 100644
index 75641106ab..0000000000
--- a/contrib/go/_std_1.18/src/internal/intern/intern.go
+++ /dev/null
@@ -1,178 +0,0 @@
-// Copyright 2020 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package intern lets you make smaller comparable values by boxing
-// a larger comparable value (such as a 16 byte string header) down
-// into a globally unique 8 byte pointer.
-//
-// The globally unique pointers are garbage collected with weak
-// references and finalizers. This package hides that.
-package intern
-
-import (
-	"internal/godebug"
-	"runtime"
-	"sync"
-	"unsafe"
-)
-
-// A Value pointer is the handle to an underlying comparable value.
-// See func Get for how Value pointers may be used.
-type Value struct {
-	_      [0]func() // prevent people from accidentally using value type as comparable
-	cmpVal any
-	// resurrected is guarded by mu (for all instances of Value).
-	// It is set true whenever v is synthesized from a uintptr.
-	resurrected bool
-}
-
-// Get returns the comparable value passed to the Get func
-// that returned v.
-func (v *Value) Get() any { return v.cmpVal }
-
-// key is a key in our global value map.
-// It contains type-specialized fields to avoid allocations
-// when converting common types to empty interfaces.
-type key struct {
-	s      string
-	cmpVal any
-	// isString reports whether key contains a string.
-	// Without it, the zero value of key is ambiguous.
-	isString bool
-}
-
-// keyFor returns a key to use with cmpVal.
-func keyFor(cmpVal any) key {
-	if s, ok := cmpVal.(string); ok {
-		return key{s: s, isString: true}
-	}
-	return key{cmpVal: cmpVal}
-}
-
-// Value returns a *Value built from k.
-func (k key) Value() *Value {
-	if k.isString {
-		return &Value{cmpVal: k.s}
-	}
-	return &Value{cmpVal: k.cmpVal}
-}
-
-var (
-	// mu guards valMap, a weakref map of *Value by underlying value.
-	// It also guards the resurrected field of all *Values.
-	mu      sync.Mutex
-	valMap  = map[key]uintptr{} // to uintptr(*Value)
-	valSafe = safeMap()         // non-nil in safe+leaky mode
-)
-
-// safeMap returns a non-nil map if we're in safe-but-leaky mode,
-// as controlled by GODEBUG=intern=leaky
-func safeMap() map[key]*Value {
-	if godebug.Get("intern") == "leaky" {
-		return map[key]*Value{}
-	}
-	return nil
-}
-
-// Get returns a pointer representing the comparable value cmpVal.
-//
-// The returned pointer will be the same for Get(v) and Get(v2)
-// if and only if v == v2, and can be used as a map key.
-func Get(cmpVal any) *Value {
-	return get(keyFor(cmpVal))
-}
-
-// GetByString is identical to Get, except that it is specialized for strings.
-// This avoids an allocation from putting a string into an interface{}
-// to pass as an argument to Get.
-func GetByString(s string) *Value {
-	return get(key{s: s, isString: true})
-}
-
-// We play unsafe games that violate Go's rules (and assume a non-moving
-// collector). So we quiet Go here.
-// See the comment below Get for more implementation details.
-//go:nocheckptr
-func get(k key) *Value {
-	mu.Lock()
-	defer mu.Unlock()
-
-	var v *Value
-	if valSafe != nil {
-		v = valSafe[k]
-	} else if addr, ok := valMap[k]; ok {
-		v = (*Value)(unsafe.Pointer(addr))
-		v.resurrected = true
-	}
-	if v != nil {
-		return v
-	}
-	v = k.Value()
-	if valSafe != nil {
-		valSafe[k] = v
-	} else {
-		// SetFinalizer before uintptr conversion (theoretical concern;
-		// see https://github.com/go4org/intern/issues/13)
-		runtime.SetFinalizer(v, finalize)
-		valMap[k] = uintptr(unsafe.Pointer(v))
-	}
-	return v
-}
-
-func finalize(v *Value) {
-	mu.Lock()
-	defer mu.Unlock()
-	if v.resurrected {
-		// We lost the race. Somebody resurrected it while we
-		// were about to finalize it. Try again next round.
-		v.resurrected = false
-		runtime.SetFinalizer(v, finalize)
-		return
-	}
-	delete(valMap, keyFor(v.cmpVal))
-}
-
-// Interning is simple if you don't require that unused values be
-// garbage collectable. But we do require that; we don't want to be
-// DOS vector. We do this by using a uintptr to hide the pointer from
-// the garbage collector, and using a finalizer to eliminate the
-// pointer when no other code is using it.
-//
-// The obvious implementation of this is to use a
-// map[interface{}]uintptr-of-*interface{}, and set up a finalizer to
-// delete from the map. Unfortunately, this is racy. Because pointers
-// are being created in violation of Go's unsafety rules, it's
-// possible to create a pointer to a value concurrently with the GC
-// concluding that the value can be collected. There are other races
-// that break the equality invariant as well, but the use-after-free
-// will cause a runtime crash.
-//
-// To make this work, the finalizer needs to know that no references
-// have been unsafely created since the finalizer was set up. To do
-// this, values carry a "resurrected" sentinel, which gets set
-// whenever a pointer is unsafely created. If the finalizer encounters
-// the sentinel, it clears the sentinel and delays collection for one
-// additional GC cycle, by re-installing itself as finalizer. This
-// ensures that the unsafely created pointer is visible to the GC, and
-// will correctly prevent collection.
-//
-// This technique does mean that interned values that get reused take
-// at least 3 GC cycles to fully collect (1 to clear the sentinel, 1
-// to clean up the unsafe map, 1 to be actually deleted).
-//
-// @ianlancetaylor commented in
-// https://github.com/golang/go/issues/41303#issuecomment-717401656
-// that it is possible to implement weak references in terms of
-// finalizers without unsafe. Unfortunately, the approach he outlined
-// does not work here, for two reasons. First, there is no way to
-// construct a strong pointer out of a weak pointer; our map stores
-// weak pointers, but we must return strong pointers to callers.
-// Second, and more fundamentally, we must return not just _a_ strong
-// pointer to callers, but _the same_ strong pointer to callers. In
-// order to return _the same_ strong pointer to callers, we must track
-// it, which is exactly what we cannot do with strong pointers.
-//
-// See https://github.com/inetaf/netaddr/issues/53 for more
-// discussion, and https://github.com/go4org/intern/issues/2 for an
-// illustration of the subtleties at play.
diff --git a/contrib/go/_std_1.18/src/internal/nettrace/nettrace.go b/contrib/go/_std_1.18/src/internal/nettrace/nettrace.go
deleted file mode 100644
index 6e0dbe73bb..0000000000
--- a/contrib/go/_std_1.18/src/internal/nettrace/nettrace.go
+++ /dev/null
@@ -1,45 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package nettrace contains internal hooks for tracing activity in
-// the net package. This package is purely internal for use by the
-// net/http/httptrace package and has no stable API exposed to end
-// users.
-package nettrace
-
-// TraceKey is a context.Context Value key. Its associated value should
-// be a *Trace struct.
-type TraceKey struct{}
-
-// LookupIPAltResolverKey is a context.Context Value key used by tests to
-// specify an alternate resolver func.
-// It is not exposed to outsider users. (But see issue 12503)
-// The value should be the same type as lookupIP:
-//     func lookupIP(ctx context.Context, host string) ([]IPAddr, error)
-type LookupIPAltResolverKey struct{}
-
-// Trace contains a set of hooks for tracing events within
-// the net package. Any specific hook may be nil.
-type Trace struct {
-	// DNSStart is called with the hostname of a DNS lookup
-	// before it begins.
-	DNSStart func(name string)
-
-	// DNSDone is called after a DNS lookup completes (or fails).
-	// The coalesced parameter is whether singleflight de-duped
-	// the call. The addrs are of type net.IPAddr but can't
-	// actually be for circular dependency reasons.
-	DNSDone func(netIPs []any, coalesced bool, err error)
-
-	// ConnectStart is called before a Dial, excluding Dials made
-	// during DNS lookups. In the case of DualStack (Happy Eyeballs)
-	// dialing, this may be called multiple times, from multiple
-	// goroutines.
-	ConnectStart func(network, addr string)
-
-	// ConnectStart is called after a Dial with the results, excluding
-	// Dials made during DNS lookups. It may also be called multiple
-	// times, like ConnectStart.
-	ConnectDone func(network, addr string, err error)
-}
diff --git a/contrib/go/_std_1.18/src/internal/poll/errno_unix.go b/contrib/go/_std_1.18/src/internal/poll/errno_unix.go
deleted file mode 100644
index c177519732..0000000000
--- a/contrib/go/_std_1.18/src/internal/poll/errno_unix.go
+++ /dev/null
@@ -1,33 +0,0 @@
-// Copyright 2019 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
-
-package poll
-
-import "syscall"
-
-// Do the interface allocations only once for common
-// Errno values.
-var (
-	errEAGAIN error = syscall.EAGAIN
-	errEINVAL error = syscall.EINVAL
-	errENOENT error = syscall.ENOENT
-)
-
-// errnoErr returns common boxed Errno values, to prevent
-// allocations at runtime.
-func errnoErr(e syscall.Errno) error {
-	switch e {
-	case 0:
-		return nil
-	case syscall.EAGAIN:
-		return errEAGAIN
-	case syscall.EINVAL:
-		return errEINVAL
-	case syscall.ENOENT:
-		return errENOENT
-	}
-	return e
-}
diff --git a/contrib/go/_std_1.18/src/internal/poll/fcntl_libc.go b/contrib/go/_std_1.18/src/internal/poll/fcntl_libc.go
deleted file mode 100644
index f503d7a336..0000000000
--- a/contrib/go/_std_1.18/src/internal/poll/fcntl_libc.go
+++ /dev/null
@@ -1,13 +0,0 @@
-// Copyright 2019 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || solaris
-
-package poll
-
-import _ "unsafe" // for go:linkname
-
-// Implemented in the syscall package.
-//go:linkname fcntl syscall.fcntl
-func fcntl(fd int, cmd int, arg int) (int, error)
diff --git a/contrib/go/_std_1.18/src/internal/poll/fd.go b/contrib/go/_std_1.18/src/internal/poll/fd.go
deleted file mode 100644
index 69a90054d3..0000000000
--- a/contrib/go/_std_1.18/src/internal/poll/fd.go
+++ /dev/null
@@ -1,82 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package poll supports non-blocking I/O on file descriptors with polling.
-// This supports I/O operations that block only a goroutine, not a thread.
-// This is used by the net and os packages.
-// It uses a poller built into the runtime, with support from the
-// runtime scheduler.
-package poll
-
-import (
-	"errors"
-)
-
-// errNetClosing is the type of the variable ErrNetClosing.
-// This is used to implement the net.Error interface.
-type errNetClosing struct{}
-
-// Error returns the error message for ErrNetClosing.
-// Keep this string consistent because of issue #4373:
-// since historically programs have not been able to detect
-// this error, they look for the string.
-func (e errNetClosing) Error() string { return "use of closed network connection" }
-
-func (e errNetClosing) Timeout() bool   { return false }
-func (e errNetClosing) Temporary() bool { return false }
-
-// ErrNetClosing is returned when a network descriptor is used after
-// it has been closed.
-var ErrNetClosing = errNetClosing{}
-
-// ErrFileClosing is returned when a file descriptor is used after it
-// has been closed.
-var ErrFileClosing = errors.New("use of closed file")
-
-// ErrNoDeadline is returned when a request is made to set a deadline
-// on a file type that does not use the poller.
-var ErrNoDeadline = errors.New("file type does not support deadline")
-
-// Return the appropriate closing error based on isFile.
-func errClosing(isFile bool) error {
-	if isFile {
-		return ErrFileClosing
-	}
-	return ErrNetClosing
-}
-
-// ErrDeadlineExceeded is returned for an expired deadline.
-// This is exported by the os package as os.ErrDeadlineExceeded.
-var ErrDeadlineExceeded error = &DeadlineExceededError{}
-
-// DeadlineExceededError is returned for an expired deadline.
-type DeadlineExceededError struct{}
-
-// Implement the net.Error interface.
-// The string is "i/o timeout" because that is what was returned
-// by earlier Go versions. Changing it may break programs that
-// match on error strings.
-func (e *DeadlineExceededError) Error() string   { return "i/o timeout" }
-func (e *DeadlineExceededError) Timeout() bool   { return true }
-func (e *DeadlineExceededError) Temporary() bool { return true }
-
-// ErrNotPollable is returned when the file or socket is not suitable
-// for event notification.
-var ErrNotPollable = errors.New("not pollable")
-
-// consume removes data from a slice of byte slices, for writev.
-func consume(v *[][]byte, n int64) {
-	for len(*v) > 0 {
-		ln0 := int64(len((*v)[0]))
-		if ln0 > n {
-			(*v)[0] = (*v)[0][n:]
-			return
-		}
-		n -= ln0
-		*v = (*v)[1:]
-	}
-}
-
-// TestHookDidWritev is a hook for testing writev.
-var TestHookDidWritev = func(wrote int) {}
diff --git a/contrib/go/_std_1.18/src/internal/poll/fd_opendir_darwin.go b/contrib/go/_std_1.18/src/internal/poll/fd_opendir_darwin.go
deleted file mode 100644
index 8eb770c358..0000000000
--- a/contrib/go/_std_1.18/src/internal/poll/fd_opendir_darwin.go
+++ /dev/null
@@ -1,38 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package poll
-
-import (
-	"syscall"
-	_ "unsafe" // for go:linkname
-)
-
-// OpenDir returns a pointer to a DIR structure suitable for
-// ReadDir. In case of an error, the name of the failed
-// syscall is returned along with a syscall.Errno.
-func (fd *FD) OpenDir() (uintptr, string, error) {
-	// fdopendir(3) takes control of the file descriptor,
-	// so use a dup.
-	fd2, call, err := fd.Dup()
-	if err != nil {
-		return 0, call, err
-	}
-	var dir uintptr
-	for {
-		dir, err = fdopendir(fd2)
-		if err != syscall.EINTR {
-			break
-		}
-	}
-	if err != nil {
-		syscall.Close(fd2)
-		return 0, "fdopendir", err
-	}
-	return dir, "", nil
-}
-
-// Implemented in syscall/syscall_darwin.go.
-//go:linkname fdopendir syscall.fdopendir
-func fdopendir(fd int) (dir uintptr, err error)
diff --git a/contrib/go/_std_1.18/src/internal/poll/fd_poll_runtime.go b/contrib/go/_std_1.18/src/internal/poll/fd_poll_runtime.go
deleted file mode 100644
index 4a4dddfd27..0000000000
--- a/contrib/go/_std_1.18/src/internal/poll/fd_poll_runtime.go
+++ /dev/null
@@ -1,168 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || windows || solaris
-
-package poll
-
-import (
-	"errors"
-	"sync"
-	"syscall"
-	"time"
-	_ "unsafe" // for go:linkname
-)
-
-// runtimeNano returns the current value of the runtime clock in nanoseconds.
-//go:linkname runtimeNano runtime.nanotime
-func runtimeNano() int64
-
-func runtime_pollServerInit()
-func runtime_pollOpen(fd uintptr) (uintptr, int)
-func runtime_pollClose(ctx uintptr)
-func runtime_pollWait(ctx uintptr, mode int) int
-func runtime_pollWaitCanceled(ctx uintptr, mode int) int
-func runtime_pollReset(ctx uintptr, mode int) int
-func runtime_pollSetDeadline(ctx uintptr, d int64, mode int)
-func runtime_pollUnblock(ctx uintptr)
-func runtime_isPollServerDescriptor(fd uintptr) bool
-
-type pollDesc struct {
-	runtimeCtx uintptr
-}
-
-var serverInit sync.Once
-
-func (pd *pollDesc) init(fd *FD) error {
-	serverInit.Do(runtime_pollServerInit)
-	ctx, errno := runtime_pollOpen(uintptr(fd.Sysfd))
-	if errno != 0 {
-		return errnoErr(syscall.Errno(errno))
-	}
-	pd.runtimeCtx = ctx
-	return nil
-}
-
-func (pd *pollDesc) close() {
-	if pd.runtimeCtx == 0 {
-		return
-	}
-	runtime_pollClose(pd.runtimeCtx)
-	pd.runtimeCtx = 0
-}
-
-// Evict evicts fd from the pending list, unblocking any I/O running on fd.
-func (pd *pollDesc) evict() {
-	if pd.runtimeCtx == 0 {
-		return
-	}
-	runtime_pollUnblock(pd.runtimeCtx)
-}
-
-func (pd *pollDesc) prepare(mode int, isFile bool) error {
-	if pd.runtimeCtx == 0 {
-		return nil
-	}
-	res := runtime_pollReset(pd.runtimeCtx, mode)
-	return convertErr(res, isFile)
-}
-
-func (pd *pollDesc) prepareRead(isFile bool) error {
-	return pd.prepare('r', isFile)
-}
-
-func (pd *pollDesc) prepareWrite(isFile bool) error {
-	return pd.prepare('w', isFile)
-}
-
-func (pd *pollDesc) wait(mode int, isFile bool) error {
-	if pd.runtimeCtx == 0 {
-		return errors.New("waiting for unsupported file type")
-	}
-	res := runtime_pollWait(pd.runtimeCtx, mode)
-	return convertErr(res, isFile)
-}
-
-func (pd *pollDesc) waitRead(isFile bool) error {
-	return pd.wait('r', isFile)
-}
-
-func (pd *pollDesc) waitWrite(isFile bool) error {
-	return pd.wait('w', isFile)
-}
-
-func (pd *pollDesc) waitCanceled(mode int) {
-	if pd.runtimeCtx == 0 {
-		return
-	}
-	runtime_pollWaitCanceled(pd.runtimeCtx, mode)
-}
-
-func (pd *pollDesc) pollable() bool {
-	return pd.runtimeCtx != 0
-}
-
-// Error values returned by runtime_pollReset and runtime_pollWait.
-// These must match the values in runtime/netpoll.go.
-const (
-	pollNoError        = 0
-	pollErrClosing     = 1
-	pollErrTimeout     = 2
-	pollErrNotPollable = 3
-)
-
-func convertErr(res int, isFile bool) error {
-	switch res {
-	case pollNoError:
-		return nil
-	case pollErrClosing:
-		return errClosing(isFile)
-	case pollErrTimeout:
-		return ErrDeadlineExceeded
-	case pollErrNotPollable:
-		return ErrNotPollable
-	}
-	println("unreachable: ", res)
-	panic("unreachable")
-}
-
-// SetDeadline sets the read and write deadlines associated with fd.
-func (fd *FD) SetDeadline(t time.Time) error {
-	return setDeadlineImpl(fd, t, 'r'+'w')
-}
-
-// SetReadDeadline sets the read deadline associated with fd.
-func (fd *FD) SetReadDeadline(t time.Time) error {
-	return setDeadlineImpl(fd, t, 'r')
-}
-
-// SetWriteDeadline sets the write deadline associated with fd.
-func (fd *FD) SetWriteDeadline(t time.Time) error {
-	return setDeadlineImpl(fd, t, 'w')
-}
-
-func setDeadlineImpl(fd *FD, t time.Time, mode int) error {
-	var d int64
-	if !t.IsZero() {
-		d = int64(time.Until(t))
-		if d == 0 {
-			d = -1 // don't confuse deadline right now with no deadline
-		}
-	}
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	if fd.pd.runtimeCtx == 0 {
-		return ErrNoDeadline
-	}
-	runtime_pollSetDeadline(fd.pd.runtimeCtx, d, mode)
-	return nil
-}
-
-// IsPollDescriptor reports whether fd is the descriptor being used by the poller.
-// This is only used for testing.
-func IsPollDescriptor(fd uintptr) bool {
-	return runtime_isPollServerDescriptor(fd)
-}
diff --git a/contrib/go/_std_1.18/src/internal/poll/fd_posix.go b/contrib/go/_std_1.18/src/internal/poll/fd_posix.go
deleted file mode 100644
index dc1e29c6b7..0000000000
--- a/contrib/go/_std_1.18/src/internal/poll/fd_posix.go
+++ /dev/null
@@ -1,79 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris || windows
-
-package poll
-
-import (
-	"io"
-	"syscall"
-)
-
-// eofError returns io.EOF when fd is available for reading end of
-// file.
-func (fd *FD) eofError(n int, err error) error {
-	if n == 0 && err == nil && fd.ZeroReadIsEOF {
-		return io.EOF
-	}
-	return err
-}
-
-// Shutdown wraps syscall.Shutdown.
-func (fd *FD) Shutdown(how int) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return syscall.Shutdown(fd.Sysfd, how)
-}
-
-// Fchown wraps syscall.Fchown.
-func (fd *FD) Fchown(uid, gid int) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return ignoringEINTR(func() error {
-		return syscall.Fchown(fd.Sysfd, uid, gid)
-	})
-}
-
-// Ftruncate wraps syscall.Ftruncate.
-func (fd *FD) Ftruncate(size int64) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return ignoringEINTR(func() error {
-		return syscall.Ftruncate(fd.Sysfd, size)
-	})
-}
-
-// RawControl invokes the user-defined function f for a non-IO
-// operation.
-func (fd *FD) RawControl(f func(uintptr)) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	f(uintptr(fd.Sysfd))
-	return nil
-}
-
-// ignoringEINTR makes a function call and repeats it if it returns
-// an EINTR error. This appears to be required even though we install all
-// signal handlers with SA_RESTART: see #22838, #38033, #38836, #40846.
-// Also #20400 and #36644 are issues in which a signal handler is
-// installed without setting SA_RESTART. None of these are the common case,
-// but there are enough of them that it seems that we can't avoid
-// an EINTR loop.
-func ignoringEINTR(fn func() error) error {
-	for {
-		err := fn()
-		if err != syscall.EINTR {
-			return err
-		}
-	}
-}
diff --git a/contrib/go/_std_1.18/src/internal/poll/fd_unix.go b/contrib/go/_std_1.18/src/internal/poll/fd_unix.go
deleted file mode 100644
index 85971a16cd..0000000000
--- a/contrib/go/_std_1.18/src/internal/poll/fd_unix.go
+++ /dev/null
@@ -1,799 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris
-
-package poll
-
-import (
-	"internal/syscall/unix"
-	"io"
-	"sync/atomic"
-	"syscall"
-)
-
-// FD is a file descriptor. The net and os packages use this type as a
-// field of a larger type representing a network connection or OS file.
-type FD struct {
-	// Lock sysfd and serialize access to Read and Write methods.
-	fdmu fdMutex
-
-	// System file descriptor. Immutable until Close.
-	Sysfd int
-
-	// I/O poller.
-	pd pollDesc
-
-	// Writev cache.
-	iovecs *[]syscall.Iovec
-
-	// Semaphore signaled when file is closed.
-	csema uint32
-
-	// Non-zero if this file has been set to blocking mode.
-	isBlocking uint32
-
-	// Whether this is a streaming descriptor, as opposed to a
-	// packet-based descriptor like a UDP socket. Immutable.
-	IsStream bool
-
-	// Whether a zero byte read indicates EOF. This is false for a
-	// message based socket connection.
-	ZeroReadIsEOF bool
-
-	// Whether this is a file rather than a network socket.
-	isFile bool
-}
-
-// Init initializes the FD. The Sysfd field should already be set.
-// This can be called multiple times on a single FD.
-// The net argument is a network name from the net package (e.g., "tcp"),
-// or "file".
-// Set pollable to true if fd should be managed by runtime netpoll.
-func (fd *FD) Init(net string, pollable bool) error {
-	// We don't actually care about the various network types.
-	if net == "file" {
-		fd.isFile = true
-	}
-	if !pollable {
-		fd.isBlocking = 1
-		return nil
-	}
-	err := fd.pd.init(fd)
-	if err != nil {
-		// If we could not initialize the runtime poller,
-		// assume we are using blocking mode.
-		fd.isBlocking = 1
-	}
-	return err
-}
-
-// Destroy closes the file descriptor. This is called when there are
-// no remaining references.
-func (fd *FD) destroy() error {
-	// Poller may want to unregister fd in readiness notification mechanism,
-	// so this must be executed before CloseFunc.
-	fd.pd.close()
-
-	// We don't use ignoringEINTR here because POSIX does not define
-	// whether the descriptor is closed if close returns EINTR.
-	// If the descriptor is indeed closed, using a loop would race
-	// with some other goroutine opening a new descriptor.
-	// (The Linux kernel guarantees that it is closed on an EINTR error.)
-	err := CloseFunc(fd.Sysfd)
-
-	fd.Sysfd = -1
-	runtime_Semrelease(&fd.csema)
-	return err
-}
-
-// Close closes the FD. The underlying file descriptor is closed by the
-// destroy method when there are no remaining references.
-func (fd *FD) Close() error {
-	if !fd.fdmu.increfAndClose() {
-		return errClosing(fd.isFile)
-	}
-
-	// Unblock any I/O.  Once it all unblocks and returns,
-	// so that it cannot be referring to fd.sysfd anymore,
-	// the final decref will close fd.sysfd. This should happen
-	// fairly quickly, since all the I/O is non-blocking, and any
-	// attempts to block in the pollDesc will return errClosing(fd.isFile).
-	fd.pd.evict()
-
-	// The call to decref will call destroy if there are no other
-	// references.
-	err := fd.decref()
-
-	// Wait until the descriptor is closed. If this was the only
-	// reference, it is already closed. Only wait if the file has
-	// not been set to blocking mode, as otherwise any current I/O
-	// may be blocking, and that would block the Close.
-	// No need for an atomic read of isBlocking, increfAndClose means
-	// we have exclusive access to fd.
-	if fd.isBlocking == 0 {
-		runtime_Semacquire(&fd.csema)
-	}
-
-	return err
-}
-
-// SetBlocking puts the file into blocking mode.
-func (fd *FD) SetBlocking() error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	// Atomic store so that concurrent calls to SetBlocking
-	// do not cause a race condition. isBlocking only ever goes
-	// from 0 to 1 so there is no real race here.
-	atomic.StoreUint32(&fd.isBlocking, 1)
-	return syscall.SetNonblock(fd.Sysfd, false)
-}
-
-// Darwin and FreeBSD can't read or write 2GB+ files at a time,
-// even on 64-bit systems.
-// The same is true of socket implementations on many systems.
-// See golang.org/issue/7812 and golang.org/issue/16266.
-// Use 1GB instead of, say, 2GB-1, to keep subsequent reads aligned.
-const maxRW = 1 << 30
-
-// Read implements io.Reader.
-func (fd *FD) Read(p []byte) (int, error) {
-	if err := fd.readLock(); err != nil {
-		return 0, err
-	}
-	defer fd.readUnlock()
-	if len(p) == 0 {
-		// If the caller wanted a zero byte read, return immediately
-		// without trying (but after acquiring the readLock).
-		// Otherwise syscall.Read returns 0, nil which looks like
-		// io.EOF.
-		// TODO(bradfitz): make it wait for readability? (Issue 15735)
-		return 0, nil
-	}
-	if err := fd.pd.prepareRead(fd.isFile); err != nil {
-		return 0, err
-	}
-	if fd.IsStream && len(p) > maxRW {
-		p = p[:maxRW]
-	}
-	for {
-		n, err := ignoringEINTRIO(syscall.Read, fd.Sysfd, p)
-		if err != nil {
-			n = 0
-			if err == syscall.EAGAIN && fd.pd.pollable() {
-				if err = fd.pd.waitRead(fd.isFile); err == nil {
-					continue
-				}
-			}
-		}
-		err = fd.eofError(n, err)
-		return n, err
-	}
-}
-
-// Pread wraps the pread system call.
-func (fd *FD) Pread(p []byte, off int64) (int, error) {
-	// Call incref, not readLock, because since pread specifies the
-	// offset it is independent from other reads.
-	// Similarly, using the poller doesn't make sense for pread.
-	if err := fd.incref(); err != nil {
-		return 0, err
-	}
-	if fd.IsStream && len(p) > maxRW {
-		p = p[:maxRW]
-	}
-	var (
-		n   int
-		err error
-	)
-	for {
-		n, err = syscall.Pread(fd.Sysfd, p, off)
-		if err != syscall.EINTR {
-			break
-		}
-	}
-	if err != nil {
-		n = 0
-	}
-	fd.decref()
-	err = fd.eofError(n, err)
-	return n, err
-}
-
-// ReadFrom wraps the recvfrom network call.
-func (fd *FD) ReadFrom(p []byte) (int, syscall.Sockaddr, error) {
-	if err := fd.readLock(); err != nil {
-		return 0, nil, err
-	}
-	defer fd.readUnlock()
-	if err := fd.pd.prepareRead(fd.isFile); err != nil {
-		return 0, nil, err
-	}
-	for {
-		n, sa, err := syscall.Recvfrom(fd.Sysfd, p, 0)
-		if err != nil {
-			if err == syscall.EINTR {
-				continue
-			}
-			n = 0
-			if err == syscall.EAGAIN && fd.pd.pollable() {
-				if err = fd.pd.waitRead(fd.isFile); err == nil {
-					continue
-				}
-			}
-		}
-		err = fd.eofError(n, err)
-		return n, sa, err
-	}
-}
-
-// ReadFromInet4 wraps the recvfrom network call for IPv4.
-func (fd *FD) ReadFromInet4(p []byte, from *syscall.SockaddrInet4) (int, error) {
-	if err := fd.readLock(); err != nil {
-		return 0, err
-	}
-	defer fd.readUnlock()
-	if err := fd.pd.prepareRead(fd.isFile); err != nil {
-		return 0, err
-	}
-	for {
-		n, err := unix.RecvfromInet4(fd.Sysfd, p, 0, from)
-		if err != nil {
-			if err == syscall.EINTR {
-				continue
-			}
-			n = 0
-			if err == syscall.EAGAIN && fd.pd.pollable() {
-				if err = fd.pd.waitRead(fd.isFile); err == nil {
-					continue
-				}
-			}
-		}
-		err = fd.eofError(n, err)
-		return n, err
-	}
-}
-
-// ReadFromInet6 wraps the recvfrom network call for IPv6.
-func (fd *FD) ReadFromInet6(p []byte, from *syscall.SockaddrInet6) (int, error) {
-	if err := fd.readLock(); err != nil {
-		return 0, err
-	}
-	defer fd.readUnlock()
-	if err := fd.pd.prepareRead(fd.isFile); err != nil {
-		return 0, err
-	}
-	for {
-		n, err := unix.RecvfromInet6(fd.Sysfd, p, 0, from)
-		if err != nil {
-			if err == syscall.EINTR {
-				continue
-			}
-			n = 0
-			if err == syscall.EAGAIN && fd.pd.pollable() {
-				if err = fd.pd.waitRead(fd.isFile); err == nil {
-					continue
-				}
-			}
-		}
-		err = fd.eofError(n, err)
-		return n, err
-	}
-}
-
-// ReadMsg wraps the recvmsg network call.
-func (fd *FD) ReadMsg(p []byte, oob []byte, flags int) (int, int, int, syscall.Sockaddr, error) {
-	if err := fd.readLock(); err != nil {
-		return 0, 0, 0, nil, err
-	}
-	defer fd.readUnlock()
-	if err := fd.pd.prepareRead(fd.isFile); err != nil {
-		return 0, 0, 0, nil, err
-	}
-	for {
-		n, oobn, sysflags, sa, err := syscall.Recvmsg(fd.Sysfd, p, oob, flags)
-		if err != nil {
-			if err == syscall.EINTR {
-				continue
-			}
-			// TODO(dfc) should n and oobn be set to 0
-			if err == syscall.EAGAIN && fd.pd.pollable() {
-				if err = fd.pd.waitRead(fd.isFile); err == nil {
-					continue
-				}
-			}
-		}
-		err = fd.eofError(n, err)
-		return n, oobn, sysflags, sa, err
-	}
-}
-
-// ReadMsgInet4 is ReadMsg, but specialized for syscall.SockaddrInet4.
-func (fd *FD) ReadMsgInet4(p []byte, oob []byte, flags int, sa4 *syscall.SockaddrInet4) (int, int, int, error) {
-	if err := fd.readLock(); err != nil {
-		return 0, 0, 0, err
-	}
-	defer fd.readUnlock()
-	if err := fd.pd.prepareRead(fd.isFile); err != nil {
-		return 0, 0, 0, err
-	}
-	for {
-		n, oobn, sysflags, err := unix.RecvmsgInet4(fd.Sysfd, p, oob, flags, sa4)
-		if err != nil {
-			if err == syscall.EINTR {
-				continue
-			}
-			// TODO(dfc) should n and oobn be set to 0
-			if err == syscall.EAGAIN && fd.pd.pollable() {
-				if err = fd.pd.waitRead(fd.isFile); err == nil {
-					continue
-				}
-			}
-		}
-		err = fd.eofError(n, err)
-		return n, oobn, sysflags, err
-	}
-}
-
-// ReadMsgInet6 is ReadMsg, but specialized for syscall.SockaddrInet6.
-func (fd *FD) ReadMsgInet6(p []byte, oob []byte, flags int, sa6 *syscall.SockaddrInet6) (int, int, int, error) {
-	if err := fd.readLock(); err != nil {
-		return 0, 0, 0, err
-	}
-	defer fd.readUnlock()
-	if err := fd.pd.prepareRead(fd.isFile); err != nil {
-		return 0, 0, 0, err
-	}
-	for {
-		n, oobn, sysflags, err := unix.RecvmsgInet6(fd.Sysfd, p, oob, flags, sa6)
-		if err != nil {
-			if err == syscall.EINTR {
-				continue
-			}
-			// TODO(dfc) should n and oobn be set to 0
-			if err == syscall.EAGAIN && fd.pd.pollable() {
-				if err = fd.pd.waitRead(fd.isFile); err == nil {
-					continue
-				}
-			}
-		}
-		err = fd.eofError(n, err)
-		return n, oobn, sysflags, err
-	}
-}
-
-// Write implements io.Writer.
-func (fd *FD) Write(p []byte) (int, error) {
-	if err := fd.writeLock(); err != nil {
-		return 0, err
-	}
-	defer fd.writeUnlock()
-	if err := fd.pd.prepareWrite(fd.isFile); err != nil {
-		return 0, err
-	}
-	var nn int
-	for {
-		max := len(p)
-		if fd.IsStream && max-nn > maxRW {
-			max = nn + maxRW
-		}
-		n, err := ignoringEINTRIO(syscall.Write, fd.Sysfd, p[nn:max])
-		if n > 0 {
-			nn += n
-		}
-		if nn == len(p) {
-			return nn, err
-		}
-		if err == syscall.EAGAIN && fd.pd.pollable() {
-			if err = fd.pd.waitWrite(fd.isFile); err == nil {
-				continue
-			}
-		}
-		if err != nil {
-			return nn, err
-		}
-		if n == 0 {
-			return nn, io.ErrUnexpectedEOF
-		}
-	}
-}
-
-// Pwrite wraps the pwrite system call.
-func (fd *FD) Pwrite(p []byte, off int64) (int, error) {
-	// Call incref, not writeLock, because since pwrite specifies the
-	// offset it is independent from other writes.
-	// Similarly, using the poller doesn't make sense for pwrite.
-	if err := fd.incref(); err != nil {
-		return 0, err
-	}
-	defer fd.decref()
-	var nn int
-	for {
-		max := len(p)
-		if fd.IsStream && max-nn > maxRW {
-			max = nn + maxRW
-		}
-		n, err := syscall.Pwrite(fd.Sysfd, p[nn:max], off+int64(nn))
-		if err == syscall.EINTR {
-			continue
-		}
-		if n > 0 {
-			nn += n
-		}
-		if nn == len(p) {
-			return nn, err
-		}
-		if err != nil {
-			return nn, err
-		}
-		if n == 0 {
-			return nn, io.ErrUnexpectedEOF
-		}
-	}
-}
-
-// WriteToInet4 wraps the sendto network call for IPv4 addresses.
-func (fd *FD) WriteToInet4(p []byte, sa *syscall.SockaddrInet4) (int, error) {
-	if err := fd.writeLock(); err != nil {
-		return 0, err
-	}
-	defer fd.writeUnlock()
-	if err := fd.pd.prepareWrite(fd.isFile); err != nil {
-		return 0, err
-	}
-	for {
-		err := unix.SendtoInet4(fd.Sysfd, p, 0, sa)
-		if err == syscall.EINTR {
-			continue
-		}
-		if err == syscall.EAGAIN && fd.pd.pollable() {
-			if err = fd.pd.waitWrite(fd.isFile); err == nil {
-				continue
-			}
-		}
-		if err != nil {
-			return 0, err
-		}
-		return len(p), nil
-	}
-}
-
-// WriteToInet6 wraps the sendto network call for IPv6 addresses.
-func (fd *FD) WriteToInet6(p []byte, sa *syscall.SockaddrInet6) (int, error) {
-	if err := fd.writeLock(); err != nil {
-		return 0, err
-	}
-	defer fd.writeUnlock()
-	if err := fd.pd.prepareWrite(fd.isFile); err != nil {
-		return 0, err
-	}
-	for {
-		err := unix.SendtoInet6(fd.Sysfd, p, 0, sa)
-		if err == syscall.EINTR {
-			continue
-		}
-		if err == syscall.EAGAIN && fd.pd.pollable() {
-			if err = fd.pd.waitWrite(fd.isFile); err == nil {
-				continue
-			}
-		}
-		if err != nil {
-			return 0, err
-		}
-		return len(p), nil
-	}
-}
-
-// WriteTo wraps the sendto network call.
-func (fd *FD) WriteTo(p []byte, sa syscall.Sockaddr) (int, error) {
-	if err := fd.writeLock(); err != nil {
-		return 0, err
-	}
-	defer fd.writeUnlock()
-	if err := fd.pd.prepareWrite(fd.isFile); err != nil {
-		return 0, err
-	}
-	for {
-		err := syscall.Sendto(fd.Sysfd, p, 0, sa)
-		if err == syscall.EINTR {
-			continue
-		}
-		if err == syscall.EAGAIN && fd.pd.pollable() {
-			if err = fd.pd.waitWrite(fd.isFile); err == nil {
-				continue
-			}
-		}
-		if err != nil {
-			return 0, err
-		}
-		return len(p), nil
-	}
-}
-
-// WriteMsg wraps the sendmsg network call.
-func (fd *FD) WriteMsg(p []byte, oob []byte, sa syscall.Sockaddr) (int, int, error) {
-	if err := fd.writeLock(); err != nil {
-		return 0, 0, err
-	}
-	defer fd.writeUnlock()
-	if err := fd.pd.prepareWrite(fd.isFile); err != nil {
-		return 0, 0, err
-	}
-	for {
-		n, err := syscall.SendmsgN(fd.Sysfd, p, oob, sa, 0)
-		if err == syscall.EINTR {
-			continue
-		}
-		if err == syscall.EAGAIN && fd.pd.pollable() {
-			if err = fd.pd.waitWrite(fd.isFile); err == nil {
-				continue
-			}
-		}
-		if err != nil {
-			return n, 0, err
-		}
-		return n, len(oob), err
-	}
-}
-
-// WriteMsgInet4 is WriteMsg specialized for syscall.SockaddrInet4.
-func (fd *FD) WriteMsgInet4(p []byte, oob []byte, sa *syscall.SockaddrInet4) (int, int, error) {
-	if err := fd.writeLock(); err != nil {
-		return 0, 0, err
-	}
-	defer fd.writeUnlock()
-	if err := fd.pd.prepareWrite(fd.isFile); err != nil {
-		return 0, 0, err
-	}
-	for {
-		n, err := unix.SendmsgNInet4(fd.Sysfd, p, oob, sa, 0)
-		if err == syscall.EINTR {
-			continue
-		}
-		if err == syscall.EAGAIN && fd.pd.pollable() {
-			if err = fd.pd.waitWrite(fd.isFile); err == nil {
-				continue
-			}
-		}
-		if err != nil {
-			return n, 0, err
-		}
-		return n, len(oob), err
-	}
-}
-
-// WriteMsgInet6 is WriteMsg specialized for syscall.SockaddrInet6.
-func (fd *FD) WriteMsgInet6(p []byte, oob []byte, sa *syscall.SockaddrInet6) (int, int, error) {
-	if err := fd.writeLock(); err != nil {
-		return 0, 0, err
-	}
-	defer fd.writeUnlock()
-	if err := fd.pd.prepareWrite(fd.isFile); err != nil {
-		return 0, 0, err
-	}
-	for {
-		n, err := unix.SendmsgNInet6(fd.Sysfd, p, oob, sa, 0)
-		if err == syscall.EINTR {
-			continue
-		}
-		if err == syscall.EAGAIN && fd.pd.pollable() {
-			if err = fd.pd.waitWrite(fd.isFile); err == nil {
-				continue
-			}
-		}
-		if err != nil {
-			return n, 0, err
-		}
-		return n, len(oob), err
-	}
-}
-
-// Accept wraps the accept network call.
-func (fd *FD) Accept() (int, syscall.Sockaddr, string, error) {
-	if err := fd.readLock(); err != nil {
-		return -1, nil, "", err
-	}
-	defer fd.readUnlock()
-
-	if err := fd.pd.prepareRead(fd.isFile); err != nil {
-		return -1, nil, "", err
-	}
-	for {
-		s, rsa, errcall, err := accept(fd.Sysfd)
-		if err == nil {
-			return s, rsa, "", err
-		}
-		switch err {
-		case syscall.EINTR:
-			continue
-		case syscall.EAGAIN:
-			if fd.pd.pollable() {
-				if err = fd.pd.waitRead(fd.isFile); err == nil {
-					continue
-				}
-			}
-		case syscall.ECONNABORTED:
-			// This means that a socket on the listen
-			// queue was closed before we Accept()ed it;
-			// it's a silly error, so try again.
-			continue
-		}
-		return -1, nil, errcall, err
-	}
-}
-
-// Seek wraps syscall.Seek.
-func (fd *FD) Seek(offset int64, whence int) (int64, error) {
-	if err := fd.incref(); err != nil {
-		return 0, err
-	}
-	defer fd.decref()
-	return syscall.Seek(fd.Sysfd, offset, whence)
-}
-
-// ReadDirent wraps syscall.ReadDirent.
-// We treat this like an ordinary system call rather than a call
-// that tries to fill the buffer.
-func (fd *FD) ReadDirent(buf []byte) (int, error) {
-	if err := fd.incref(); err != nil {
-		return 0, err
-	}
-	defer fd.decref()
-	for {
-		n, err := ignoringEINTRIO(syscall.ReadDirent, fd.Sysfd, buf)
-		if err != nil {
-			n = 0
-			if err == syscall.EAGAIN && fd.pd.pollable() {
-				if err = fd.pd.waitRead(fd.isFile); err == nil {
-					continue
-				}
-			}
-		}
-		// Do not call eofError; caller does not expect to see io.EOF.
-		return n, err
-	}
-}
-
-// Fchmod wraps syscall.Fchmod.
-func (fd *FD) Fchmod(mode uint32) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return ignoringEINTR(func() error {
-		return syscall.Fchmod(fd.Sysfd, mode)
-	})
-}
-
-// Fchdir wraps syscall.Fchdir.
-func (fd *FD) Fchdir() error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return syscall.Fchdir(fd.Sysfd)
-}
-
-// Fstat wraps syscall.Fstat
-func (fd *FD) Fstat(s *syscall.Stat_t) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return ignoringEINTR(func() error {
-		return syscall.Fstat(fd.Sysfd, s)
-	})
-}
-
-// tryDupCloexec indicates whether F_DUPFD_CLOEXEC should be used.
-// If the kernel doesn't support it, this is set to 0.
-var tryDupCloexec = int32(1)
-
-// DupCloseOnExec dups fd and marks it close-on-exec.
-func DupCloseOnExec(fd int) (int, string, error) {
-	if syscall.F_DUPFD_CLOEXEC != 0 && atomic.LoadInt32(&tryDupCloexec) == 1 {
-		r0, e1 := fcntl(fd, syscall.F_DUPFD_CLOEXEC, 0)
-		if e1 == nil {
-			return r0, "", nil
-		}
-		switch e1.(syscall.Errno) {
-		case syscall.EINVAL, syscall.ENOSYS:
-			// Old kernel, or js/wasm (which returns
-			// ENOSYS). Fall back to the portable way from
-			// now on.
-			atomic.StoreInt32(&tryDupCloexec, 0)
-		default:
-			return -1, "fcntl", e1
-		}
-	}
-	return dupCloseOnExecOld(fd)
-}
-
-// dupCloseOnExecOld is the traditional way to dup an fd and
-// set its O_CLOEXEC bit, using two system calls.
-func dupCloseOnExecOld(fd int) (int, string, error) {
-	syscall.ForkLock.RLock()
-	defer syscall.ForkLock.RUnlock()
-	newfd, err := syscall.Dup(fd)
-	if err != nil {
-		return -1, "dup", err
-	}
-	syscall.CloseOnExec(newfd)
-	return newfd, "", nil
-}
-
-// Dup duplicates the file descriptor.
-func (fd *FD) Dup() (int, string, error) {
-	if err := fd.incref(); err != nil {
-		return -1, "", err
-	}
-	defer fd.decref()
-	return DupCloseOnExec(fd.Sysfd)
-}
-
-// On Unix variants only, expose the IO event for the net code.
-
-// WaitWrite waits until data can be read from fd.
-func (fd *FD) WaitWrite() error {
-	return fd.pd.waitWrite(fd.isFile)
-}
-
-// WriteOnce is for testing only. It makes a single write call.
-func (fd *FD) WriteOnce(p []byte) (int, error) {
-	if err := fd.writeLock(); err != nil {
-		return 0, err
-	}
-	defer fd.writeUnlock()
-	return ignoringEINTRIO(syscall.Write, fd.Sysfd, p)
-}
-
-// RawRead invokes the user-defined function f for a read operation.
-func (fd *FD) RawRead(f func(uintptr) bool) error {
-	if err := fd.readLock(); err != nil {
-		return err
-	}
-	defer fd.readUnlock()
-	if err := fd.pd.prepareRead(fd.isFile); err != nil {
-		return err
-	}
-	for {
-		if f(uintptr(fd.Sysfd)) {
-			return nil
-		}
-		if err := fd.pd.waitRead(fd.isFile); err != nil {
-			return err
-		}
-	}
-}
-
-// RawWrite invokes the user-defined function f for a write operation.
-func (fd *FD) RawWrite(f func(uintptr) bool) error {
-	if err := fd.writeLock(); err != nil {
-		return err
-	}
-	defer fd.writeUnlock()
-	if err := fd.pd.prepareWrite(fd.isFile); err != nil {
-		return err
-	}
-	for {
-		if f(uintptr(fd.Sysfd)) {
-			return nil
-		}
-		if err := fd.pd.waitWrite(fd.isFile); err != nil {
-			return err
-		}
-	}
-}
-
-// ignoringEINTRIO is like ignoringEINTR, but just for IO calls.
-func ignoringEINTRIO(fn func(fd int, p []byte) (int, error), fd int, p []byte) (int, error) {
-	for {
-		n, err := fn(fd, p)
-		if err != syscall.EINTR {
-			return n, err
-		}
-	}
-}
diff --git a/contrib/go/_std_1.18/src/internal/poll/fd_writev_darwin.go b/contrib/go/_std_1.18/src/internal/poll/fd_writev_darwin.go
deleted file mode 100644
index 8137510c8b..0000000000
--- a/contrib/go/_std_1.18/src/internal/poll/fd_writev_darwin.go
+++ /dev/null
@@ -1,16 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build darwin
-
-package poll
-
-import (
-	"syscall"
-	_ "unsafe" // for go:linkname
-)
-
-// Implemented in syscall/syscall_darwin.go.
-//go:linkname writev syscall.writev
-func writev(fd int, iovecs []syscall.Iovec) (uintptr, error)
diff --git a/contrib/go/_std_1.18/src/internal/poll/hook_cloexec.go b/contrib/go/_std_1.18/src/internal/poll/hook_cloexec.go
deleted file mode 100644
index c941cb5235..0000000000
--- a/contrib/go/_std_1.18/src/internal/poll/hook_cloexec.go
+++ /dev/null
@@ -1,12 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build dragonfly || freebsd || illumos || linux || netbsd || openbsd
-
-package poll
-
-import "syscall"
-
-// Accept4Func is used to hook the accept4 call.
-var Accept4Func func(int, int) (int, syscall.Sockaddr, error) = syscall.Accept4
diff --git a/contrib/go/_std_1.18/src/internal/poll/hook_unix.go b/contrib/go/_std_1.18/src/internal/poll/hook_unix.go
deleted file mode 100644
index c9aa4b4ca2..0000000000
--- a/contrib/go/_std_1.18/src/internal/poll/hook_unix.go
+++ /dev/null
@@ -1,15 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris
-
-package poll
-
-import "syscall"
-
-// CloseFunc is used to hook the close call.
-var CloseFunc func(int) error = syscall.Close
-
-// AcceptFunc is used to hook the accept call.
-var AcceptFunc func(int) (int, syscall.Sockaddr, error) = syscall.Accept
diff --git a/contrib/go/_std_1.18/src/internal/poll/sock_cloexec.go b/contrib/go/_std_1.18/src/internal/poll/sock_cloexec.go
deleted file mode 100644
index d849fda0b0..0000000000
--- a/contrib/go/_std_1.18/src/internal/poll/sock_cloexec.go
+++ /dev/null
@@ -1,50 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file implements accept for platforms that provide a fast path for
-// setting SetNonblock and CloseOnExec.
-
-//go:build dragonfly || freebsd || illumos || linux || netbsd || openbsd
-
-package poll
-
-import "syscall"
-
-// Wrapper around the accept system call that marks the returned file
-// descriptor as nonblocking and close-on-exec.
-func accept(s int) (int, syscall.Sockaddr, string, error) {
-	ns, sa, err := Accept4Func(s, syscall.SOCK_NONBLOCK|syscall.SOCK_CLOEXEC)
-	// On Linux the accept4 system call was introduced in 2.6.28
-	// kernel and on FreeBSD it was introduced in 10 kernel. If we
-	// get an ENOSYS error on both Linux and FreeBSD, or EINVAL
-	// error on Linux, fall back to using accept.
-	switch err {
-	case nil:
-		return ns, sa, "", nil
-	default: // errors other than the ones listed
-		return -1, sa, "accept4", err
-	case syscall.ENOSYS: // syscall missing
-	case syscall.EINVAL: // some Linux use this instead of ENOSYS
-	case syscall.EACCES: // some Linux use this instead of ENOSYS
-	case syscall.EFAULT: // some Linux use this instead of ENOSYS
-	}
-
-	// See ../syscall/exec_unix.go for description of ForkLock.
-	// It is probably okay to hold the lock across syscall.Accept
-	// because we have put fd.sysfd into non-blocking mode.
-	// However, a call to the File method will put it back into
-	// blocking mode. We can't take that risk, so no use of ForkLock here.
-	ns, sa, err = AcceptFunc(s)
-	if err == nil {
-		syscall.CloseOnExec(ns)
-	}
-	if err != nil {
-		return -1, nil, "accept", err
-	}
-	if err = syscall.SetNonblock(ns, true); err != nil {
-		CloseFunc(ns)
-		return -1, nil, "setnonblock", err
-	}
-	return ns, sa, "", nil
-}
diff --git a/contrib/go/_std_1.18/src/internal/poll/sockopt.go b/contrib/go/_std_1.18/src/internal/poll/sockopt.go
deleted file mode 100644
index 2d354700c5..0000000000
--- a/contrib/go/_std_1.18/src/internal/poll/sockopt.go
+++ /dev/null
@@ -1,36 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris || windows
-
-package poll
-
-import "syscall"
-
-// SetsockoptInt wraps the setsockopt network call with an int argument.
-func (fd *FD) SetsockoptInt(level, name, arg int) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return syscall.SetsockoptInt(fd.Sysfd, level, name, arg)
-}
-
-// SetsockoptInet4Addr wraps the setsockopt network call with an IPv4 address.
-func (fd *FD) SetsockoptInet4Addr(level, name int, arg [4]byte) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return syscall.SetsockoptInet4Addr(fd.Sysfd, level, name, arg)
-}
-
-// SetsockoptLinger wraps the setsockopt network call with a Linger argument.
-func (fd *FD) SetsockoptLinger(level, name int, l *syscall.Linger) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return syscall.SetsockoptLinger(fd.Sysfd, level, name, l)
-}
diff --git a/contrib/go/_std_1.18/src/internal/poll/sockopt_unix.go b/contrib/go/_std_1.18/src/internal/poll/sockopt_unix.go
deleted file mode 100644
index 54be1cc4b6..0000000000
--- a/contrib/go/_std_1.18/src/internal/poll/sockopt_unix.go
+++ /dev/null
@@ -1,18 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
-
-package poll
-
-import "syscall"
-
-// SetsockoptByte wraps the setsockopt network call with a byte argument.
-func (fd *FD) SetsockoptByte(level, name int, arg byte) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return syscall.SetsockoptByte(fd.Sysfd, level, name, arg)
-}
diff --git a/contrib/go/_std_1.18/src/internal/poll/sockoptip.go b/contrib/go/_std_1.18/src/internal/poll/sockoptip.go
deleted file mode 100644
index 7fc9aeefb3..0000000000
--- a/contrib/go/_std_1.18/src/internal/poll/sockoptip.go
+++ /dev/null
@@ -1,27 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris || windows
-
-package poll
-
-import "syscall"
-
-// SetsockoptIPMreq wraps the setsockopt network call with an IPMreq argument.
-func (fd *FD) SetsockoptIPMreq(level, name int, mreq *syscall.IPMreq) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return syscall.SetsockoptIPMreq(fd.Sysfd, level, name, mreq)
-}
-
-// SetsockoptIPv6Mreq wraps the setsockopt network call with an IPv6Mreq argument.
-func (fd *FD) SetsockoptIPv6Mreq(level, name int, mreq *syscall.IPv6Mreq) error {
-	if err := fd.incref(); err != nil {
-		return err
-	}
-	defer fd.decref()
-	return syscall.SetsockoptIPv6Mreq(fd.Sysfd, level, name, mreq)
-}
diff --git a/contrib/go/_std_1.18/src/internal/poll/sys_cloexec.go b/contrib/go/_std_1.18/src/internal/poll/sys_cloexec.go
deleted file mode 100644
index 312ed24a44..0000000000
--- a/contrib/go/_std_1.18/src/internal/poll/sys_cloexec.go
+++ /dev/null
@@ -1,36 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file implements accept for platforms that do not provide a fast path for
-// setting SetNonblock and CloseOnExec.
-
-//go:build aix || darwin || (js && wasm) || (solaris && !illumos)
-
-package poll
-
-import (
-	"syscall"
-)
-
-// Wrapper around the accept system call that marks the returned file
-// descriptor as nonblocking and close-on-exec.
-func accept(s int) (int, syscall.Sockaddr, string, error) {
-	// See ../syscall/exec_unix.go for description of ForkLock.
-	// It is probably okay to hold the lock across syscall.Accept
-	// because we have put fd.sysfd into non-blocking mode.
-	// However, a call to the File method will put it back into
-	// blocking mode. We can't take that risk, so no use of ForkLock here.
-	ns, sa, err := AcceptFunc(s)
-	if err == nil {
-		syscall.CloseOnExec(ns)
-	}
-	if err != nil {
-		return -1, nil, "accept", err
-	}
-	if err = syscall.SetNonblock(ns, true); err != nil {
-		CloseFunc(ns)
-		return -1, nil, "setnonblock", err
-	}
-	return ns, sa, "", nil
-}
diff --git a/contrib/go/_std_1.18/src/internal/reflectlite/type.go b/contrib/go/_std_1.18/src/internal/reflectlite/type.go
deleted file mode 100644
index 8f649600d2..0000000000
--- a/contrib/go/_std_1.18/src/internal/reflectlite/type.go
+++ /dev/null
@@ -1,972 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package reflectlite implements lightweight version of reflect, not using
-// any package except for "runtime" and "unsafe".
-package reflectlite
-
-import (
-	"internal/unsafeheader"
-	"unsafe"
-)
-
-// Type is the representation of a Go type.
-//
-// Not all methods apply to all kinds of types. Restrictions,
-// if any, are noted in the documentation for each method.
-// Use the Kind method to find out the kind of type before
-// calling kind-specific methods. Calling a method
-// inappropriate to the kind of type causes a run-time panic.
-//
-// Type values are comparable, such as with the == operator,
-// so they can be used as map keys.
-// Two Type values are equal if they represent identical types.
-type Type interface {
-	// Methods applicable to all types.
-
-	// Name returns the type's name within its package for a defined type.
-	// For other (non-defined) types it returns the empty string.
-	Name() string
-
-	// PkgPath returns a defined type's package path, that is, the import path
-	// that uniquely identifies the package, such as "encoding/base64".
-	// If the type was predeclared (string, error) or not defined (*T, struct{},
-	// []int, or A where A is an alias for a non-defined type), the package path
-	// will be the empty string.
-	PkgPath() string
-
-	// Size returns the number of bytes needed to store
-	// a value of the given type; it is analogous to unsafe.Sizeof.
-	Size() uintptr
-
-	// Kind returns the specific kind of this type.
-	Kind() Kind
-
-	// Implements reports whether the type implements the interface type u.
-	Implements(u Type) bool
-
-	// AssignableTo reports whether a value of the type is assignable to type u.
-	AssignableTo(u Type) bool
-
-	// Comparable reports whether values of this type are comparable.
-	Comparable() bool
-
-	// String returns a string representation of the type.
-	// The string representation may use shortened package names
-	// (e.g., base64 instead of "encoding/base64") and is not
-	// guaranteed to be unique among types. To test for type identity,
-	// compare the Types directly.
-	String() string
-
-	// Elem returns a type's element type.
-	// It panics if the type's Kind is not Ptr.
-	Elem() Type
-
-	common() *rtype
-	uncommon() *uncommonType
-}
-
-/*
- * These data structures are known to the compiler (../../cmd/internal/reflectdata/reflect.go).
- * A few are known to ../runtime/type.go to convey to debuggers.
- * They are also known to ../runtime/type.go.
- */
-
-// A Kind represents the specific kind of type that a Type represents.
-// The zero Kind is not a valid kind.
-type Kind uint
-
-const (
-	Invalid Kind = iota
-	Bool
-	Int
-	Int8
-	Int16
-	Int32
-	Int64
-	Uint
-	Uint8
-	Uint16
-	Uint32
-	Uint64
-	Uintptr
-	Float32
-	Float64
-	Complex64
-	Complex128
-	Array
-	Chan
-	Func
-	Interface
-	Map
-	Pointer
-	Slice
-	String
-	Struct
-	UnsafePointer
-)
-
-const Ptr = Pointer
-
-// tflag is used by an rtype to signal what extra type information is
-// available in the memory directly following the rtype value.
-//
-// tflag values must be kept in sync with copies in:
-//	cmd/compile/internal/reflectdata/reflect.go
-//	cmd/link/internal/ld/decodesym.go
-//	runtime/type.go
-type tflag uint8
-
-const (
-	// tflagUncommon means that there is a pointer, *uncommonType,
-	// just beyond the outer type structure.
-	//
-	// For example, if t.Kind() == Struct and t.tflag&tflagUncommon != 0,
-	// then t has uncommonType data and it can be accessed as:
-	//
-	//	type tUncommon struct {
-	//		structType
-	//		u uncommonType
-	//	}
-	//	u := &(*tUncommon)(unsafe.Pointer(t)).u
-	tflagUncommon tflag = 1 << 0
-
-	// tflagExtraStar means the name in the str field has an
-	// extraneous '*' prefix. This is because for most types T in
-	// a program, the type *T also exists and reusing the str data
-	// saves binary size.
-	tflagExtraStar tflag = 1 << 1
-
-	// tflagNamed means the type has a name.
-	tflagNamed tflag = 1 << 2
-
-	// tflagRegularMemory means that equal and hash functions can treat
-	// this type as a single region of t.size bytes.
-	tflagRegularMemory tflag = 1 << 3
-)
-
-// rtype is the common implementation of most values.
-// It is embedded in other struct types.
-//
-// rtype must be kept in sync with ../runtime/type.go:/^type._type.
-type rtype struct {
-	size       uintptr
-	ptrdata    uintptr // number of bytes in the type that can contain pointers
-	hash       uint32  // hash of type; avoids computation in hash tables
-	tflag      tflag   // extra type information flags
-	align      uint8   // alignment of variable with this type
-	fieldAlign uint8   // alignment of struct field with this type
-	kind       uint8   // enumeration for C
-	// function for comparing objects of this type
-	// (ptr to object A, ptr to object B) -> ==?
-	equal     func(unsafe.Pointer, unsafe.Pointer) bool
-	gcdata    *byte   // garbage collection data
-	str       nameOff // string form
-	ptrToThis typeOff // type for pointer to this type, may be zero
-}
-
-// Method on non-interface type
-type method struct {
-	name nameOff // name of method
-	mtyp typeOff // method type (without receiver)
-	ifn  textOff // fn used in interface call (one-word receiver)
-	tfn  textOff // fn used for normal method call
-}
-
-// uncommonType is present only for defined types or types with methods
-// (if T is a defined type, the uncommonTypes for T and *T have methods).
-// Using a pointer to this struct reduces the overall size required
-// to describe a non-defined type with no methods.
-type uncommonType struct {
-	pkgPath nameOff // import path; empty for built-in types like int, string
-	mcount  uint16  // number of methods
-	xcount  uint16  // number of exported methods
-	moff    uint32  // offset from this uncommontype to [mcount]method
-	_       uint32  // unused
-}
-
-// chanDir represents a channel type's direction.
-type chanDir int
-
-const (
-	recvDir chanDir             = 1 << iota // <-chan
-	sendDir                                 // chan<-
-	bothDir = recvDir | sendDir             // chan
-)
-
-// arrayType represents a fixed array type.
-type arrayType struct {
-	rtype
-	elem  *rtype // array element type
-	slice *rtype // slice type
-	len   uintptr
-}
-
-// chanType represents a channel type.
-type chanType struct {
-	rtype
-	elem *rtype  // channel element type
-	dir  uintptr // channel direction (chanDir)
-}
-
-// funcType represents a function type.
-//
-// A *rtype for each in and out parameter is stored in an array that
-// directly follows the funcType (and possibly its uncommonType). So
-// a function type with one method, one input, and one output is:
-//
-//	struct {
-//		funcType
-//		uncommonType
-//		[2]*rtype    // [0] is in, [1] is out
-//	}
-type funcType struct {
-	rtype
-	inCount  uint16
-	outCount uint16 // top bit is set if last input parameter is ...
-}
-
-// imethod represents a method on an interface type
-type imethod struct {
-	name nameOff // name of method
-	typ  typeOff // .(*FuncType) underneath
-}
-
-// interfaceType represents an interface type.
-type interfaceType struct {
-	rtype
-	pkgPath name      // import path
-	methods []imethod // sorted by hash
-}
-
-// mapType represents a map type.
-type mapType struct {
-	rtype
-	key    *rtype // map key type
-	elem   *rtype // map element (value) type
-	bucket *rtype // internal bucket structure
-	// function for hashing keys (ptr to key, seed) -> hash
-	hasher     func(unsafe.Pointer, uintptr) uintptr
-	keysize    uint8  // size of key slot
-	valuesize  uint8  // size of value slot
-	bucketsize uint16 // size of bucket
-	flags      uint32
-}
-
-// ptrType represents a pointer type.
-type ptrType struct {
-	rtype
-	elem *rtype // pointer element (pointed at) type
-}
-
-// sliceType represents a slice type.
-type sliceType struct {
-	rtype
-	elem *rtype // slice element type
-}
-
-// Struct field
-type structField struct {
-	name        name    // name is always non-empty
-	typ         *rtype  // type of field
-	offsetEmbed uintptr // byte offset of field<<1 | isEmbedded
-}
-
-func (f *structField) offset() uintptr {
-	return f.offsetEmbed >> 1
-}
-
-func (f *structField) embedded() bool {
-	return f.offsetEmbed&1 != 0
-}
-
-// structType represents a struct type.
-type structType struct {
-	rtype
-	pkgPath name
-	fields  []structField // sorted by offset
-}
-
-// name is an encoded type name with optional extra data.
-//
-// The first byte is a bit field containing:
-//
-//	1<<0 the name is exported
-//	1<<1 tag data follows the name
-//	1<<2 pkgPath nameOff follows the name and tag
-//
-// The next two bytes are the data length:
-//
-//	 l := uint16(data[1])<<8 | uint16(data[2])
-//
-// Bytes [3:3+l] are the string data.
-//
-// If tag data follows then bytes 3+l and 3+l+1 are the tag length,
-// with the data following.
-//
-// If the import path follows, then 4 bytes at the end of
-// the data form a nameOff. The import path is only set for concrete
-// methods that are defined in a different package than their type.
-//
-// If a name starts with "*", then the exported bit represents
-// whether the pointed to type is exported.
-type name struct {
-	bytes *byte
-}
-
-func (n name) data(off int, whySafe string) *byte {
-	return (*byte)(add(unsafe.Pointer(n.bytes), uintptr(off), whySafe))
-}
-
-func (n name) isExported() bool {
-	return (*n.bytes)&(1<<0) != 0
-}
-
-func (n name) hasTag() bool {
-	return (*n.bytes)&(1<<1) != 0
-}
-
-// readVarint parses a varint as encoded by encoding/binary.
-// It returns the number of encoded bytes and the encoded value.
-func (n name) readVarint(off int) (int, int) {
-	v := 0
-	for i := 0; ; i++ {
-		x := *n.data(off+i, "read varint")
-		v += int(x&0x7f) << (7 * i)
-		if x&0x80 == 0 {
-			return i + 1, v
-		}
-	}
-}
-
-func (n name) name() (s string) {
-	if n.bytes == nil {
-		return
-	}
-	i, l := n.readVarint(1)
-	hdr := (*unsafeheader.String)(unsafe.Pointer(&s))
-	hdr.Data = unsafe.Pointer(n.data(1+i, "non-empty string"))
-	hdr.Len = l
-	return
-}
-
-func (n name) tag() (s string) {
-	if !n.hasTag() {
-		return ""
-	}
-	i, l := n.readVarint(1)
-	i2, l2 := n.readVarint(1 + i + l)
-	hdr := (*unsafeheader.String)(unsafe.Pointer(&s))
-	hdr.Data = unsafe.Pointer(n.data(1+i+l+i2, "non-empty string"))
-	hdr.Len = l2
-	return
-}
-
-func (n name) pkgPath() string {
-	if n.bytes == nil || *n.data(0, "name flag field")&(1<<2) == 0 {
-		return ""
-	}
-	i, l := n.readVarint(1)
-	off := 1 + i + l
-	if n.hasTag() {
-		i2, l2 := n.readVarint(off)
-		off += i2 + l2
-	}
-	var nameOff int32
-	// Note that this field may not be aligned in memory,
-	// so we cannot use a direct int32 assignment here.
-	copy((*[4]byte)(unsafe.Pointer(&nameOff))[:], (*[4]byte)(unsafe.Pointer(n.data(off, "name offset field")))[:])
-	pkgPathName := name{(*byte)(resolveTypeOff(unsafe.Pointer(n.bytes), nameOff))}
-	return pkgPathName.name()
-}
-
-/*
- * The compiler knows the exact layout of all the data structures above.
- * The compiler does not know about the data structures and methods below.
- */
-
-const (
-	kindDirectIface = 1 << 5
-	kindGCProg      = 1 << 6 // Type.gc points to GC program
-	kindMask        = (1 << 5) - 1
-)
-
-// String returns the name of k.
-func (k Kind) String() string {
-	if int(k) < len(kindNames) {
-		return kindNames[k]
-	}
-	return kindNames[0]
-}
-
-var kindNames = []string{
-	Invalid:       "invalid",
-	Bool:          "bool",
-	Int:           "int",
-	Int8:          "int8",
-	Int16:         "int16",
-	Int32:         "int32",
-	Int64:         "int64",
-	Uint:          "uint",
-	Uint8:         "uint8",
-	Uint16:        "uint16",
-	Uint32:        "uint32",
-	Uint64:        "uint64",
-	Uintptr:       "uintptr",
-	Float32:       "float32",
-	Float64:       "float64",
-	Complex64:     "complex64",
-	Complex128:    "complex128",
-	Array:         "array",
-	Chan:          "chan",
-	Func:          "func",
-	Interface:     "interface",
-	Map:           "map",
-	Ptr:           "ptr",
-	Slice:         "slice",
-	String:        "string",
-	Struct:        "struct",
-	UnsafePointer: "unsafe.Pointer",
-}
-
-func (t *uncommonType) methods() []method {
-	if t.mcount == 0 {
-		return nil
-	}
-	return (*[1 << 16]method)(add(unsafe.Pointer(t), uintptr(t.moff), "t.mcount > 0"))[:t.mcount:t.mcount]
-}
-
-func (t *uncommonType) exportedMethods() []method {
-	if t.xcount == 0 {
-		return nil
-	}
-	return (*[1 << 16]method)(add(unsafe.Pointer(t), uintptr(t.moff), "t.xcount > 0"))[:t.xcount:t.xcount]
-}
-
-// resolveNameOff resolves a name offset from a base pointer.
-// The (*rtype).nameOff method is a convenience wrapper for this function.
-// Implemented in the runtime package.
-func resolveNameOff(ptrInModule unsafe.Pointer, off int32) unsafe.Pointer
-
-// resolveTypeOff resolves an *rtype offset from a base type.
-// The (*rtype).typeOff method is a convenience wrapper for this function.
-// Implemented in the runtime package.
-func resolveTypeOff(rtype unsafe.Pointer, off int32) unsafe.Pointer
-
-type nameOff int32 // offset to a name
-type typeOff int32 // offset to an *rtype
-type textOff int32 // offset from top of text section
-
-func (t *rtype) nameOff(off nameOff) name {
-	return name{(*byte)(resolveNameOff(unsafe.Pointer(t), int32(off)))}
-}
-
-func (t *rtype) typeOff(off typeOff) *rtype {
-	return (*rtype)(resolveTypeOff(unsafe.Pointer(t), int32(off)))
-}
-
-func (t *rtype) uncommon() *uncommonType {
-	if t.tflag&tflagUncommon == 0 {
-		return nil
-	}
-	switch t.Kind() {
-	case Struct:
-		return &(*structTypeUncommon)(unsafe.Pointer(t)).u
-	case Ptr:
-		type u struct {
-			ptrType
-			u uncommonType
-		}
-		return &(*u)(unsafe.Pointer(t)).u
-	case Func:
-		type u struct {
-			funcType
-			u uncommonType
-		}
-		return &(*u)(unsafe.Pointer(t)).u
-	case Slice:
-		type u struct {
-			sliceType
-			u uncommonType
-		}
-		return &(*u)(unsafe.Pointer(t)).u
-	case Array:
-		type u struct {
-			arrayType
-			u uncommonType
-		}
-		return &(*u)(unsafe.Pointer(t)).u
-	case Chan:
-		type u struct {
-			chanType
-			u uncommonType
-		}
-		return &(*u)(unsafe.Pointer(t)).u
-	case Map:
-		type u struct {
-			mapType
-			u uncommonType
-		}
-		return &(*u)(unsafe.Pointer(t)).u
-	case Interface:
-		type u struct {
-			interfaceType
-			u uncommonType
-		}
-		return &(*u)(unsafe.Pointer(t)).u
-	default:
-		type u struct {
-			rtype
-			u uncommonType
-		}
-		return &(*u)(unsafe.Pointer(t)).u
-	}
-}
-
-func (t *rtype) String() string {
-	s := t.nameOff(t.str).name()
-	if t.tflag&tflagExtraStar != 0 {
-		return s[1:]
-	}
-	return s
-}
-
-func (t *rtype) Size() uintptr { return t.size }
-
-func (t *rtype) Kind() Kind { return Kind(t.kind & kindMask) }
-
-func (t *rtype) pointers() bool { return t.ptrdata != 0 }
-
-func (t *rtype) common() *rtype { return t }
-
-func (t *rtype) exportedMethods() []method {
-	ut := t.uncommon()
-	if ut == nil {
-		return nil
-	}
-	return ut.exportedMethods()
-}
-
-func (t *rtype) NumMethod() int {
-	if t.Kind() == Interface {
-		tt := (*interfaceType)(unsafe.Pointer(t))
-		return tt.NumMethod()
-	}
-	return len(t.exportedMethods())
-}
-
-func (t *rtype) PkgPath() string {
-	if t.tflag&tflagNamed == 0 {
-		return ""
-	}
-	ut := t.uncommon()
-	if ut == nil {
-		return ""
-	}
-	return t.nameOff(ut.pkgPath).name()
-}
-
-func (t *rtype) hasName() bool {
-	return t.tflag&tflagNamed != 0
-}
-
-func (t *rtype) Name() string {
-	if !t.hasName() {
-		return ""
-	}
-	s := t.String()
-	i := len(s) - 1
-	for i >= 0 && s[i] != '.' {
-		i--
-	}
-	return s[i+1:]
-}
-
-func (t *rtype) chanDir() chanDir {
-	if t.Kind() != Chan {
-		panic("reflect: chanDir of non-chan type")
-	}
-	tt := (*chanType)(unsafe.Pointer(t))
-	return chanDir(tt.dir)
-}
-
-func (t *rtype) Elem() Type {
-	switch t.Kind() {
-	case Array:
-		tt := (*arrayType)(unsafe.Pointer(t))
-		return toType(tt.elem)
-	case Chan:
-		tt := (*chanType)(unsafe.Pointer(t))
-		return toType(tt.elem)
-	case Map:
-		tt := (*mapType)(unsafe.Pointer(t))
-		return toType(tt.elem)
-	case Ptr:
-		tt := (*ptrType)(unsafe.Pointer(t))
-		return toType(tt.elem)
-	case Slice:
-		tt := (*sliceType)(unsafe.Pointer(t))
-		return toType(tt.elem)
-	}
-	panic("reflect: Elem of invalid type")
-}
-
-func (t *rtype) In(i int) Type {
-	if t.Kind() != Func {
-		panic("reflect: In of non-func type")
-	}
-	tt := (*funcType)(unsafe.Pointer(t))
-	return toType(tt.in()[i])
-}
-
-func (t *rtype) Key() Type {
-	if t.Kind() != Map {
-		panic("reflect: Key of non-map type")
-	}
-	tt := (*mapType)(unsafe.Pointer(t))
-	return toType(tt.key)
-}
-
-func (t *rtype) Len() int {
-	if t.Kind() != Array {
-		panic("reflect: Len of non-array type")
-	}
-	tt := (*arrayType)(unsafe.Pointer(t))
-	return int(tt.len)
-}
-
-func (t *rtype) NumField() int {
-	if t.Kind() != Struct {
-		panic("reflect: NumField of non-struct type")
-	}
-	tt := (*structType)(unsafe.Pointer(t))
-	return len(tt.fields)
-}
-
-func (t *rtype) NumIn() int {
-	if t.Kind() != Func {
-		panic("reflect: NumIn of non-func type")
-	}
-	tt := (*funcType)(unsafe.Pointer(t))
-	return int(tt.inCount)
-}
-
-func (t *rtype) NumOut() int {
-	if t.Kind() != Func {
-		panic("reflect: NumOut of non-func type")
-	}
-	tt := (*funcType)(unsafe.Pointer(t))
-	return len(tt.out())
-}
-
-func (t *rtype) Out(i int) Type {
-	if t.Kind() != Func {
-		panic("reflect: Out of non-func type")
-	}
-	tt := (*funcType)(unsafe.Pointer(t))
-	return toType(tt.out()[i])
-}
-
-func (t *funcType) in() []*rtype {
-	uadd := unsafe.Sizeof(*t)
-	if t.tflag&tflagUncommon != 0 {
-		uadd += unsafe.Sizeof(uncommonType{})
-	}
-	if t.inCount == 0 {
-		return nil
-	}
-	return (*[1 << 20]*rtype)(add(unsafe.Pointer(t), uadd, "t.inCount > 0"))[:t.inCount:t.inCount]
-}
-
-func (t *funcType) out() []*rtype {
-	uadd := unsafe.Sizeof(*t)
-	if t.tflag&tflagUncommon != 0 {
-		uadd += unsafe.Sizeof(uncommonType{})
-	}
-	outCount := t.outCount & (1<<15 - 1)
-	if outCount == 0 {
-		return nil
-	}
-	return (*[1 << 20]*rtype)(add(unsafe.Pointer(t), uadd, "outCount > 0"))[t.inCount : t.inCount+outCount : t.inCount+outCount]
-}
-
-// add returns p+x.
-//
-// The whySafe string is ignored, so that the function still inlines
-// as efficiently as p+x, but all call sites should use the string to
-// record why the addition is safe, which is to say why the addition
-// does not cause x to advance to the very end of p's allocation
-// and therefore point incorrectly at the next block in memory.
-func add(p unsafe.Pointer, x uintptr, whySafe string) unsafe.Pointer {
-	return unsafe.Pointer(uintptr(p) + x)
-}
-
-// NumMethod returns the number of interface methods in the type's method set.
-func (t *interfaceType) NumMethod() int { return len(t.methods) }
-
-// TypeOf returns the reflection Type that represents the dynamic type of i.
-// If i is a nil interface value, TypeOf returns nil.
-func TypeOf(i any) Type {
-	eface := *(*emptyInterface)(unsafe.Pointer(&i))
-	return toType(eface.typ)
-}
-
-func (t *rtype) Implements(u Type) bool {
-	if u == nil {
-		panic("reflect: nil type passed to Type.Implements")
-	}
-	if u.Kind() != Interface {
-		panic("reflect: non-interface type passed to Type.Implements")
-	}
-	return implements(u.(*rtype), t)
-}
-
-func (t *rtype) AssignableTo(u Type) bool {
-	if u == nil {
-		panic("reflect: nil type passed to Type.AssignableTo")
-	}
-	uu := u.(*rtype)
-	return directlyAssignable(uu, t) || implements(uu, t)
-}
-
-func (t *rtype) Comparable() bool {
-	return t.equal != nil
-}
-
-// implements reports whether the type V implements the interface type T.
-func implements(T, V *rtype) bool {
-	if T.Kind() != Interface {
-		return false
-	}
-	t := (*interfaceType)(unsafe.Pointer(T))
-	if len(t.methods) == 0 {
-		return true
-	}
-
-	// The same algorithm applies in both cases, but the
-	// method tables for an interface type and a concrete type
-	// are different, so the code is duplicated.
-	// In both cases the algorithm is a linear scan over the two
-	// lists - T's methods and V's methods - simultaneously.
-	// Since method tables are stored in a unique sorted order
-	// (alphabetical, with no duplicate method names), the scan
-	// through V's methods must hit a match for each of T's
-	// methods along the way, or else V does not implement T.
-	// This lets us run the scan in overall linear time instead of
-	// the quadratic time  a naive search would require.
-	// See also ../runtime/iface.go.
-	if V.Kind() == Interface {
-		v := (*interfaceType)(unsafe.Pointer(V))
-		i := 0
-		for j := 0; j < len(v.methods); j++ {
-			tm := &t.methods[i]
-			tmName := t.nameOff(tm.name)
-			vm := &v.methods[j]
-			vmName := V.nameOff(vm.name)
-			if vmName.name() == tmName.name() && V.typeOff(vm.typ) == t.typeOff(tm.typ) {
-				if !tmName.isExported() {
-					tmPkgPath := tmName.pkgPath()
-					if tmPkgPath == "" {
-						tmPkgPath = t.pkgPath.name()
-					}
-					vmPkgPath := vmName.pkgPath()
-					if vmPkgPath == "" {
-						vmPkgPath = v.pkgPath.name()
-					}
-					if tmPkgPath != vmPkgPath {
-						continue
-					}
-				}
-				if i++; i >= len(t.methods) {
-					return true
-				}
-			}
-		}
-		return false
-	}
-
-	v := V.uncommon()
-	if v == nil {
-		return false
-	}
-	i := 0
-	vmethods := v.methods()
-	for j := 0; j < int(v.mcount); j++ {
-		tm := &t.methods[i]
-		tmName := t.nameOff(tm.name)
-		vm := vmethods[j]
-		vmName := V.nameOff(vm.name)
-		if vmName.name() == tmName.name() && V.typeOff(vm.mtyp) == t.typeOff(tm.typ) {
-			if !tmName.isExported() {
-				tmPkgPath := tmName.pkgPath()
-				if tmPkgPath == "" {
-					tmPkgPath = t.pkgPath.name()
-				}
-				vmPkgPath := vmName.pkgPath()
-				if vmPkgPath == "" {
-					vmPkgPath = V.nameOff(v.pkgPath).name()
-				}
-				if tmPkgPath != vmPkgPath {
-					continue
-				}
-			}
-			if i++; i >= len(t.methods) {
-				return true
-			}
-		}
-	}
-	return false
-}
-
-// directlyAssignable reports whether a value x of type V can be directly
-// assigned (using memmove) to a value of type T.
-// https://golang.org/doc/go_spec.html#Assignability
-// Ignoring the interface rules (implemented elsewhere)
-// and the ideal constant rules (no ideal constants at run time).
-func directlyAssignable(T, V *rtype) bool {
-	// x's type V is identical to T?
-	if T == V {
-		return true
-	}
-
-	// Otherwise at least one of T and V must not be defined
-	// and they must have the same kind.
-	if T.hasName() && V.hasName() || T.Kind() != V.Kind() {
-		return false
-	}
-
-	// x's type T and V must  have identical underlying types.
-	return haveIdenticalUnderlyingType(T, V, true)
-}
-
-func haveIdenticalType(T, V Type, cmpTags bool) bool {
-	if cmpTags {
-		return T == V
-	}
-
-	if T.Name() != V.Name() || T.Kind() != V.Kind() {
-		return false
-	}
-
-	return haveIdenticalUnderlyingType(T.common(), V.common(), false)
-}
-
-func haveIdenticalUnderlyingType(T, V *rtype, cmpTags bool) bool {
-	if T == V {
-		return true
-	}
-
-	kind := T.Kind()
-	if kind != V.Kind() {
-		return false
-	}
-
-	// Non-composite types of equal kind have same underlying type
-	// (the predefined instance of the type).
-	if Bool <= kind && kind <= Complex128 || kind == String || kind == UnsafePointer {
-		return true
-	}
-
-	// Composite types.
-	switch kind {
-	case Array:
-		return T.Len() == V.Len() && haveIdenticalType(T.Elem(), V.Elem(), cmpTags)
-
-	case Chan:
-		// Special case:
-		// x is a bidirectional channel value, T is a channel type,
-		// and x's type V and T have identical element types.
-		if V.chanDir() == bothDir && haveIdenticalType(T.Elem(), V.Elem(), cmpTags) {
-			return true
-		}
-
-		// Otherwise continue test for identical underlying type.
-		return V.chanDir() == T.chanDir() && haveIdenticalType(T.Elem(), V.Elem(), cmpTags)
-
-	case Func:
-		t := (*funcType)(unsafe.Pointer(T))
-		v := (*funcType)(unsafe.Pointer(V))
-		if t.outCount != v.outCount || t.inCount != v.inCount {
-			return false
-		}
-		for i := 0; i < t.NumIn(); i++ {
-			if !haveIdenticalType(t.In(i), v.In(i), cmpTags) {
-				return false
-			}
-		}
-		for i := 0; i < t.NumOut(); i++ {
-			if !haveIdenticalType(t.Out(i), v.Out(i), cmpTags) {
-				return false
-			}
-		}
-		return true
-
-	case Interface:
-		t := (*interfaceType)(unsafe.Pointer(T))
-		v := (*interfaceType)(unsafe.Pointer(V))
-		if len(t.methods) == 0 && len(v.methods) == 0 {
-			return true
-		}
-		// Might have the same methods but still
-		// need a run time conversion.
-		return false
-
-	case Map:
-		return haveIdenticalType(T.Key(), V.Key(), cmpTags) && haveIdenticalType(T.Elem(), V.Elem(), cmpTags)
-
-	case Ptr, Slice:
-		return haveIdenticalType(T.Elem(), V.Elem(), cmpTags)
-
-	case Struct:
-		t := (*structType)(unsafe.Pointer(T))
-		v := (*structType)(unsafe.Pointer(V))
-		if len(t.fields) != len(v.fields) {
-			return false
-		}
-		if t.pkgPath.name() != v.pkgPath.name() {
-			return false
-		}
-		for i := range t.fields {
-			tf := &t.fields[i]
-			vf := &v.fields[i]
-			if tf.name.name() != vf.name.name() {
-				return false
-			}
-			if !haveIdenticalType(tf.typ, vf.typ, cmpTags) {
-				return false
-			}
-			if cmpTags && tf.name.tag() != vf.name.tag() {
-				return false
-			}
-			if tf.offsetEmbed != vf.offsetEmbed {
-				return false
-			}
-		}
-		return true
-	}
-
-	return false
-}
-
-type structTypeUncommon struct {
-	structType
-	u uncommonType
-}
-
-// toType converts from a *rtype to a Type that can be returned
-// to the client of package reflect. In gc, the only concern is that
-// a nil *rtype must be replaced by a nil Type, but in gccgo this
-// function takes care of ensuring that multiple *rtype for the same
-// type are coalesced into a single Type.
-func toType(t *rtype) Type {
-	if t == nil {
-		return nil
-	}
-	return t
-}
-
-// ifaceIndir reports whether t is stored indirectly in an interface value.
-func ifaceIndir(t *rtype) bool {
-	return t.kind&kindDirectIface == 0
-}
diff --git a/contrib/go/_std_1.18/src/internal/reflectlite/value.go b/contrib/go/_std_1.18/src/internal/reflectlite/value.go
deleted file mode 100644
index 966230f581..0000000000
--- a/contrib/go/_std_1.18/src/internal/reflectlite/value.go
+++ /dev/null
@@ -1,476 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package reflectlite
-
-import (
-	"internal/goarch"
-	"internal/unsafeheader"
-	"runtime"
-	"unsafe"
-)
-
-// Value is the reflection interface to a Go value.
-//
-// Not all methods apply to all kinds of values. Restrictions,
-// if any, are noted in the documentation for each method.
-// Use the Kind method to find out the kind of value before
-// calling kind-specific methods. Calling a method
-// inappropriate to the kind of type causes a run time panic.
-//
-// The zero Value represents no value.
-// Its IsValid method returns false, its Kind method returns Invalid,
-// its String method returns "<invalid Value>", and all other methods panic.
-// Most functions and methods never return an invalid value.
-// If one does, its documentation states the conditions explicitly.
-//
-// A Value can be used concurrently by multiple goroutines provided that
-// the underlying Go value can be used concurrently for the equivalent
-// direct operations.
-//
-// To compare two Values, compare the results of the Interface method.
-// Using == on two Values does not compare the underlying values
-// they represent.
-type Value struct {
-	// typ holds the type of the value represented by a Value.
-	typ *rtype
-
-	// Pointer-valued data or, if flagIndir is set, pointer to data.
-	// Valid when either flagIndir is set or typ.pointers() is true.
-	ptr unsafe.Pointer
-
-	// flag holds metadata about the value.
-	// The lowest bits are flag bits:
-	//	- flagStickyRO: obtained via unexported not embedded field, so read-only
-	//	- flagEmbedRO: obtained via unexported embedded field, so read-only
-	//	- flagIndir: val holds a pointer to the data
-	//	- flagAddr: v.CanAddr is true (implies flagIndir)
-	// Value cannot represent method values.
-	// The next five bits give the Kind of the value.
-	// This repeats typ.Kind() except for method values.
-	// The remaining 23+ bits give a method number for method values.
-	// If flag.kind() != Func, code can assume that flagMethod is unset.
-	// If ifaceIndir(typ), code can assume that flagIndir is set.
-	flag
-
-	// A method value represents a curried method invocation
-	// like r.Read for some receiver r. The typ+val+flag bits describe
-	// the receiver r, but the flag's Kind bits say Func (methods are
-	// functions), and the top bits of the flag give the method number
-	// in r's type's method table.
-}
-
-type flag uintptr
-
-const (
-	flagKindWidth        = 5 // there are 27 kinds
-	flagKindMask    flag = 1<<flagKindWidth - 1
-	flagStickyRO    flag = 1 << 5
-	flagEmbedRO     flag = 1 << 6
-	flagIndir       flag = 1 << 7
-	flagAddr        flag = 1 << 8
-	flagMethod      flag = 1 << 9
-	flagMethodShift      = 10
-	flagRO          flag = flagStickyRO | flagEmbedRO
-)
-
-func (f flag) kind() Kind {
-	return Kind(f & flagKindMask)
-}
-
-func (f flag) ro() flag {
-	if f&flagRO != 0 {
-		return flagStickyRO
-	}
-	return 0
-}
-
-// pointer returns the underlying pointer represented by v.
-// v.Kind() must be Pointer, Map, Chan, Func, or UnsafePointer
-func (v Value) pointer() unsafe.Pointer {
-	if v.typ.size != goarch.PtrSize || !v.typ.pointers() {
-		panic("can't call pointer on a non-pointer Value")
-	}
-	if v.flag&flagIndir != 0 {
-		return *(*unsafe.Pointer)(v.ptr)
-	}
-	return v.ptr
-}
-
-// packEface converts v to the empty interface.
-func packEface(v Value) any {
-	t := v.typ
-	var i any
-	e := (*emptyInterface)(unsafe.Pointer(&i))
-	// First, fill in the data portion of the interface.
-	switch {
-	case ifaceIndir(t):
-		if v.flag&flagIndir == 0 {
-			panic("bad indir")
-		}
-		// Value is indirect, and so is the interface we're making.
-		ptr := v.ptr
-		if v.flag&flagAddr != 0 {
-			// TODO: pass safe boolean from valueInterface so
-			// we don't need to copy if safe==true?
-			c := unsafe_New(t)
-			typedmemmove(t, c, ptr)
-			ptr = c
-		}
-		e.word = ptr
-	case v.flag&flagIndir != 0:
-		// Value is indirect, but interface is direct. We need
-		// to load the data at v.ptr into the interface data word.
-		e.word = *(*unsafe.Pointer)(v.ptr)
-	default:
-		// Value is direct, and so is the interface.
-		e.word = v.ptr
-	}
-	// Now, fill in the type portion. We're very careful here not
-	// to have any operation between the e.word and e.typ assignments
-	// that would let the garbage collector observe the partially-built
-	// interface value.
-	e.typ = t
-	return i
-}
-
-// unpackEface converts the empty interface i to a Value.
-func unpackEface(i any) Value {
-	e := (*emptyInterface)(unsafe.Pointer(&i))
-	// NOTE: don't read e.word until we know whether it is really a pointer or not.
-	t := e.typ
-	if t == nil {
-		return Value{}
-	}
-	f := flag(t.Kind())
-	if ifaceIndir(t) {
-		f |= flagIndir
-	}
-	return Value{t, e.word, f}
-}
-
-// A ValueError occurs when a Value method is invoked on
-// a Value that does not support it. Such cases are documented
-// in the description of each method.
-type ValueError struct {
-	Method string
-	Kind   Kind
-}
-
-func (e *ValueError) Error() string {
-	if e.Kind == 0 {
-		return "reflect: call of " + e.Method + " on zero Value"
-	}
-	return "reflect: call of " + e.Method + " on " + e.Kind.String() + " Value"
-}
-
-// methodName returns the name of the calling method,
-// assumed to be two stack frames above.
-func methodName() string {
-	pc, _, _, _ := runtime.Caller(2)
-	f := runtime.FuncForPC(pc)
-	if f == nil {
-		return "unknown method"
-	}
-	return f.Name()
-}
-
-// emptyInterface is the header for an interface{} value.
-type emptyInterface struct {
-	typ  *rtype
-	word unsafe.Pointer
-}
-
-// mustBeExported panics if f records that the value was obtained using
-// an unexported field.
-func (f flag) mustBeExported() {
-	if f == 0 {
-		panic(&ValueError{methodName(), 0})
-	}
-	if f&flagRO != 0 {
-		panic("reflect: " + methodName() + " using value obtained using unexported field")
-	}
-}
-
-// mustBeAssignable panics if f records that the value is not assignable,
-// which is to say that either it was obtained using an unexported field
-// or it is not addressable.
-func (f flag) mustBeAssignable() {
-	if f == 0 {
-		panic(&ValueError{methodName(), Invalid})
-	}
-	// Assignable if addressable and not read-only.
-	if f&flagRO != 0 {
-		panic("reflect: " + methodName() + " using value obtained using unexported field")
-	}
-	if f&flagAddr == 0 {
-		panic("reflect: " + methodName() + " using unaddressable value")
-	}
-}
-
-// CanSet reports whether the value of v can be changed.
-// A Value can be changed only if it is addressable and was not
-// obtained by the use of unexported struct fields.
-// If CanSet returns false, calling Set or any type-specific
-// setter (e.g., SetBool, SetInt) will panic.
-func (v Value) CanSet() bool {
-	return v.flag&(flagAddr|flagRO) == flagAddr
-}
-
-// Elem returns the value that the interface v contains
-// or that the pointer v points to.
-// It panics if v's Kind is not Interface or Pointer.
-// It returns the zero Value if v is nil.
-func (v Value) Elem() Value {
-	k := v.kind()
-	switch k {
-	case Interface:
-		var eface any
-		if v.typ.NumMethod() == 0 {
-			eface = *(*any)(v.ptr)
-		} else {
-			eface = (any)(*(*interface {
-				M()
-			})(v.ptr))
-		}
-		x := unpackEface(eface)
-		if x.flag != 0 {
-			x.flag |= v.flag.ro()
-		}
-		return x
-	case Pointer:
-		ptr := v.ptr
-		if v.flag&flagIndir != 0 {
-			ptr = *(*unsafe.Pointer)(ptr)
-		}
-		// The returned value's address is v's value.
-		if ptr == nil {
-			return Value{}
-		}
-		tt := (*ptrType)(unsafe.Pointer(v.typ))
-		typ := tt.elem
-		fl := v.flag&flagRO | flagIndir | flagAddr
-		fl |= flag(typ.Kind())
-		return Value{typ, ptr, fl}
-	}
-	panic(&ValueError{"reflectlite.Value.Elem", v.kind()})
-}
-
-func valueInterface(v Value) any {
-	if v.flag == 0 {
-		panic(&ValueError{"reflectlite.Value.Interface", 0})
-	}
-
-	if v.kind() == Interface {
-		// Special case: return the element inside the interface.
-		// Empty interface has one layout, all interfaces with
-		// methods have a second layout.
-		if v.numMethod() == 0 {
-			return *(*any)(v.ptr)
-		}
-		return *(*interface {
-			M()
-		})(v.ptr)
-	}
-
-	// TODO: pass safe to packEface so we don't need to copy if safe==true?
-	return packEface(v)
-}
-
-// IsNil reports whether its argument v is nil. The argument must be
-// a chan, func, interface, map, pointer, or slice value; if it is
-// not, IsNil panics. Note that IsNil is not always equivalent to a
-// regular comparison with nil in Go. For example, if v was created
-// by calling ValueOf with an uninitialized interface variable i,
-// i==nil will be true but v.IsNil will panic as v will be the zero
-// Value.
-func (v Value) IsNil() bool {
-	k := v.kind()
-	switch k {
-	case Chan, Func, Map, Pointer, UnsafePointer:
-		// if v.flag&flagMethod != 0 {
-		// 	return false
-		// }
-		ptr := v.ptr
-		if v.flag&flagIndir != 0 {
-			ptr = *(*unsafe.Pointer)(ptr)
-		}
-		return ptr == nil
-	case Interface, Slice:
-		// Both interface and slice are nil if first word is 0.
-		// Both are always bigger than a word; assume flagIndir.
-		return *(*unsafe.Pointer)(v.ptr) == nil
-	}
-	panic(&ValueError{"reflectlite.Value.IsNil", v.kind()})
-}
-
-// IsValid reports whether v represents a value.
-// It returns false if v is the zero Value.
-// If IsValid returns false, all other methods except String panic.
-// Most functions and methods never return an invalid Value.
-// If one does, its documentation states the conditions explicitly.
-func (v Value) IsValid() bool {
-	return v.flag != 0
-}
-
-// Kind returns v's Kind.
-// If v is the zero Value (IsValid returns false), Kind returns Invalid.
-func (v Value) Kind() Kind {
-	return v.kind()
-}
-
-// implemented in runtime:
-func chanlen(unsafe.Pointer) int
-func maplen(unsafe.Pointer) int
-
-// Len returns v's length.
-// It panics if v's Kind is not Array, Chan, Map, Slice, or String.
-func (v Value) Len() int {
-	k := v.kind()
-	switch k {
-	case Array:
-		tt := (*arrayType)(unsafe.Pointer(v.typ))
-		return int(tt.len)
-	case Chan:
-		return chanlen(v.pointer())
-	case Map:
-		return maplen(v.pointer())
-	case Slice:
-		// Slice is bigger than a word; assume flagIndir.
-		return (*unsafeheader.Slice)(v.ptr).Len
-	case String:
-		// String is bigger than a word; assume flagIndir.
-		return (*unsafeheader.String)(v.ptr).Len
-	}
-	panic(&ValueError{"reflect.Value.Len", v.kind()})
-}
-
-// NumMethod returns the number of exported methods in the value's method set.
-func (v Value) numMethod() int {
-	if v.typ == nil {
-		panic(&ValueError{"reflectlite.Value.NumMethod", Invalid})
-	}
-	return v.typ.NumMethod()
-}
-
-// Set assigns x to the value v.
-// It panics if CanSet returns false.
-// As in Go, x's value must be assignable to v's type.
-func (v Value) Set(x Value) {
-	v.mustBeAssignable()
-	x.mustBeExported() // do not let unexported x leak
-	var target unsafe.Pointer
-	if v.kind() == Interface {
-		target = v.ptr
-	}
-	x = x.assignTo("reflectlite.Set", v.typ, target)
-	if x.flag&flagIndir != 0 {
-		typedmemmove(v.typ, v.ptr, x.ptr)
-	} else {
-		*(*unsafe.Pointer)(v.ptr) = x.ptr
-	}
-}
-
-// Type returns v's type.
-func (v Value) Type() Type {
-	f := v.flag
-	if f == 0 {
-		panic(&ValueError{"reflectlite.Value.Type", Invalid})
-	}
-	// Method values not supported.
-	return v.typ
-}
-
-/*
- * constructors
- */
-
-// implemented in package runtime
-func unsafe_New(*rtype) unsafe.Pointer
-
-// ValueOf returns a new Value initialized to the concrete value
-// stored in the interface i. ValueOf(nil) returns the zero Value.
-func ValueOf(i any) Value {
-	if i == nil {
-		return Value{}
-	}
-
-	// TODO: Maybe allow contents of a Value to live on the stack.
-	// For now we make the contents always escape to the heap. It
-	// makes life easier in a few places (see chanrecv/mapassign
-	// comment below).
-	escapes(i)
-
-	return unpackEface(i)
-}
-
-// assignTo returns a value v that can be assigned directly to typ.
-// It panics if v is not assignable to typ.
-// For a conversion to an interface type, target is a suggested scratch space to use.
-func (v Value) assignTo(context string, dst *rtype, target unsafe.Pointer) Value {
-	// if v.flag&flagMethod != 0 {
-	// 	v = makeMethodValue(context, v)
-	// }
-
-	switch {
-	case directlyAssignable(dst, v.typ):
-		// Overwrite type so that they match.
-		// Same memory layout, so no harm done.
-		fl := v.flag&(flagAddr|flagIndir) | v.flag.ro()
-		fl |= flag(dst.Kind())
-		return Value{dst, v.ptr, fl}
-
-	case implements(dst, v.typ):
-		if target == nil {
-			target = unsafe_New(dst)
-		}
-		if v.Kind() == Interface && v.IsNil() {
-			// A nil ReadWriter passed to nil Reader is OK,
-			// but using ifaceE2I below will panic.
-			// Avoid the panic by returning a nil dst (e.g., Reader) explicitly.
-			return Value{dst, nil, flag(Interface)}
-		}
-		x := valueInterface(v)
-		if dst.NumMethod() == 0 {
-			*(*any)(target) = x
-		} else {
-			ifaceE2I(dst, x, target)
-		}
-		return Value{dst, target, flagIndir | flag(Interface)}
-	}
-
-	// Failed.
-	panic(context + ": value of type " + v.typ.String() + " is not assignable to type " + dst.String())
-}
-
-// arrayAt returns the i-th element of p,
-// an array whose elements are eltSize bytes wide.
-// The array pointed at by p must have at least i+1 elements:
-// it is invalid (but impossible to check here) to pass i >= len,
-// because then the result will point outside the array.
-// whySafe must explain why i < len. (Passing "i < len" is fine;
-// the benefit is to surface this assumption at the call site.)
-func arrayAt(p unsafe.Pointer, i int, eltSize uintptr, whySafe string) unsafe.Pointer {
-	return add(p, uintptr(i)*eltSize, "i < len")
-}
-
-func ifaceE2I(t *rtype, src any, dst unsafe.Pointer)
-
-// typedmemmove copies a value of type t to dst from src.
-//go:noescape
-func typedmemmove(t *rtype, dst, src unsafe.Pointer)
-
-// Dummy annotation marking that the value x escapes,
-// for use in cases where the reflect code is so clever that
-// the compiler cannot follow.
-func escapes(x any) {
-	if dummy.b {
-		dummy.x = x
-	}
-}
-
-var dummy struct {
-	b bool
-	x any
-}
diff --git a/contrib/go/_std_1.18/src/internal/syscall/unix/at.go b/contrib/go/_std_1.18/src/internal/syscall/unix/at.go
deleted file mode 100644
index 447d48e198..0000000000
--- a/contrib/go/_std_1.18/src/internal/syscall/unix/at.go
+++ /dev/null
@@ -1,58 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build linux || openbsd || netbsd || dragonfly
-
-package unix
-
-import (
-	"syscall"
-	"unsafe"
-)
-
-func Unlinkat(dirfd int, path string, flags int) error {
-	var p *byte
-	p, err := syscall.BytePtrFromString(path)
-	if err != nil {
-		return err
-	}
-
-	_, _, errno := syscall.Syscall(unlinkatTrap, uintptr(dirfd), uintptr(unsafe.Pointer(p)), uintptr(flags))
-	if errno != 0 {
-		return errno
-	}
-
-	return nil
-}
-
-func Openat(dirfd int, path string, flags int, perm uint32) (int, error) {
-	var p *byte
-	p, err := syscall.BytePtrFromString(path)
-	if err != nil {
-		return 0, err
-	}
-
-	fd, _, errno := syscall.Syscall6(openatTrap, uintptr(dirfd), uintptr(unsafe.Pointer(p)), uintptr(flags), uintptr(perm), 0, 0)
-	if errno != 0 {
-		return 0, errno
-	}
-
-	return int(fd), nil
-}
-
-func Fstatat(dirfd int, path string, stat *syscall.Stat_t, flags int) error {
-	var p *byte
-	p, err := syscall.BytePtrFromString(path)
-	if err != nil {
-		return err
-	}
-
-	_, _, errno := syscall.Syscall6(fstatatTrap, uintptr(dirfd), uintptr(unsafe.Pointer(p)), uintptr(unsafe.Pointer(stat)), uintptr(flags), 0, 0)
-	if errno != 0 {
-		return errno
-	}
-
-	return nil
-
-}
diff --git a/contrib/go/_std_1.18/src/internal/syscall/unix/net.go b/contrib/go/_std_1.18/src/internal/syscall/unix/net.go
deleted file mode 100644
index 85632e1c03..0000000000
--- a/contrib/go/_std_1.18/src/internal/syscall/unix/net.go
+++ /dev/null
@@ -1,44 +0,0 @@
-// Copyright 2021 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
-
-package unix
-
-import (
-	"syscall"
-	_ "unsafe"
-)
-
-//go:linkname RecvfromInet4 syscall.recvfromInet4
-//go:noescape
-func RecvfromInet4(fd int, p []byte, flags int, from *syscall.SockaddrInet4) (int, error)
-
-//go:linkname RecvfromInet6 syscall.recvfromInet6
-//go:noescape
-func RecvfromInet6(fd int, p []byte, flags int, from *syscall.SockaddrInet6) (n int, err error)
-
-//go:linkname SendtoInet4 syscall.sendtoInet4
-//go:noescape
-func SendtoInet4(fd int, p []byte, flags int, to *syscall.SockaddrInet4) (err error)
-
-//go:linkname SendtoInet6 syscall.sendtoInet6
-//go:noescape
-func SendtoInet6(fd int, p []byte, flags int, to *syscall.SockaddrInet6) (err error)
-
-//go:linkname SendmsgNInet4 syscall.sendmsgNInet4
-//go:noescape
-func SendmsgNInet4(fd int, p, oob []byte, to *syscall.SockaddrInet4, flags int) (n int, err error)
-
-//go:linkname SendmsgNInet6 syscall.sendmsgNInet6
-//go:noescape
-func SendmsgNInet6(fd int, p, oob []byte, to *syscall.SockaddrInet6, flags int) (n int, err error)
-
-//go:linkname RecvmsgInet4 syscall.recvmsgInet4
-//go:noescape
-func RecvmsgInet4(fd int, p, oob []byte, flags int, from *syscall.SockaddrInet4) (n, oobn int, recvflags int, err error)
-
-//go:linkname RecvmsgInet6 syscall.recvmsgInet6
-//go:noescape
-func RecvmsgInet6(fd int, p, oob []byte, flags int, from *syscall.SockaddrInet6) (n, oobn int, recvflags int, err error)
diff --git a/contrib/go/_std_1.18/src/internal/syscall/unix/nonblocking_libc.go b/contrib/go/_std_1.18/src/internal/syscall/unix/nonblocking_libc.go
deleted file mode 100644
index 75c6e92a6e..0000000000
--- a/contrib/go/_std_1.18/src/internal/syscall/unix/nonblocking_libc.go
+++ /dev/null
@@ -1,24 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || solaris
-
-package unix
-
-import (
-	"syscall"
-	_ "unsafe" // for go:linkname
-)
-
-func IsNonblock(fd int) (nonblocking bool, err error) {
-	flag, e1 := fcntl(fd, syscall.F_GETFL, 0)
-	if e1 != nil {
-		return false, e1
-	}
-	return flag&syscall.O_NONBLOCK != 0, nil
-}
-
-// Implemented in the syscall package.
-//go:linkname fcntl syscall.fcntl
-func fcntl(fd int, cmd int, arg int) (int, error)
diff --git a/contrib/go/_std_1.18/src/io/fs/fs.go b/contrib/go/_std_1.18/src/io/fs/fs.go
deleted file mode 100644
index 5c0d9a6664..0000000000
--- a/contrib/go/_std_1.18/src/io/fs/fs.go
+++ /dev/null
@@ -1,257 +0,0 @@
-// Copyright 2020 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package fs defines basic interfaces to a file system.
-// A file system can be provided by the host operating system
-// but also by other packages.
-package fs
-
-import (
-	"internal/oserror"
-	"time"
-	"unicode/utf8"
-)
-
-// An FS provides access to a hierarchical file system.
-//
-// The FS interface is the minimum implementation required of the file system.
-// A file system may implement additional interfaces,
-// such as ReadFileFS, to provide additional or optimized functionality.
-type FS interface {
-	// Open opens the named file.
-	//
-	// When Open returns an error, it should be of type *PathError
-	// with the Op field set to "open", the Path field set to name,
-	// and the Err field describing the problem.
-	//
-	// Open should reject attempts to open names that do not satisfy
-	// ValidPath(name), returning a *PathError with Err set to
-	// ErrInvalid or ErrNotExist.
-	Open(name string) (File, error)
-}
-
-// ValidPath reports whether the given path name
-// is valid for use in a call to Open.
-//
-// Path names passed to open are UTF-8-encoded,
-// unrooted, slash-separated sequences of path elements, like “x/y/z”.
-// Path names must not contain an element that is “.” or “..” or the empty string,
-// except for the special case that the root directory is named “.”.
-// Paths must not start or end with a slash: “/x” and “x/” are invalid.
-//
-// Note that paths are slash-separated on all systems, even Windows.
-// Paths containing other characters such as backslash and colon
-// are accepted as valid, but those characters must never be
-// interpreted by an FS implementation as path element separators.
-func ValidPath(name string) bool {
-	if !utf8.ValidString(name) {
-		return false
-	}
-
-	if name == "." {
-		// special case
-		return true
-	}
-
-	// Iterate over elements in name, checking each.
-	for {
-		i := 0
-		for i < len(name) && name[i] != '/' {
-			i++
-		}
-		elem := name[:i]
-		if elem == "" || elem == "." || elem == ".." {
-			return false
-		}
-		if i == len(name) {
-			return true // reached clean ending
-		}
-		name = name[i+1:]
-	}
-}
-
-// A File provides access to a single file.
-// The File interface is the minimum implementation required of the file.
-// Directory files should also implement ReadDirFile.
-// A file may implement io.ReaderAt or io.Seeker as optimizations.
-type File interface {
-	Stat() (FileInfo, error)
-	Read([]byte) (int, error)
-	Close() error
-}
-
-// A DirEntry is an entry read from a directory
-// (using the ReadDir function or a ReadDirFile's ReadDir method).
-type DirEntry interface {
-	// Name returns the name of the file (or subdirectory) described by the entry.
-	// This name is only the final element of the path (the base name), not the entire path.
-	// For example, Name would return "hello.go" not "home/gopher/hello.go".
-	Name() string
-
-	// IsDir reports whether the entry describes a directory.
-	IsDir() bool
-
-	// Type returns the type bits for the entry.
-	// The type bits are a subset of the usual FileMode bits, those returned by the FileMode.Type method.
-	Type() FileMode
-
-	// Info returns the FileInfo for the file or subdirectory described by the entry.
-	// The returned FileInfo may be from the time of the original directory read
-	// or from the time of the call to Info. If the file has been removed or renamed
-	// since the directory read, Info may return an error satisfying errors.Is(err, ErrNotExist).
-	// If the entry denotes a symbolic link, Info reports the information about the link itself,
-	// not the link's target.
-	Info() (FileInfo, error)
-}
-
-// A ReadDirFile is a directory file whose entries can be read with the ReadDir method.
-// Every directory file should implement this interface.
-// (It is permissible for any file to implement this interface,
-// but if so ReadDir should return an error for non-directories.)
-type ReadDirFile interface {
-	File
-
-	// ReadDir reads the contents of the directory and returns
-	// a slice of up to n DirEntry values in directory order.
-	// Subsequent calls on the same file will yield further DirEntry values.
-	//
-	// If n > 0, ReadDir returns at most n DirEntry structures.
-	// In this case, if ReadDir returns an empty slice, it will return
-	// a non-nil error explaining why.
-	// At the end of a directory, the error is io.EOF.
-	//
-	// If n <= 0, ReadDir returns all the DirEntry values from the directory
-	// in a single slice. In this case, if ReadDir succeeds (reads all the way
-	// to the end of the directory), it returns the slice and a nil error.
-	// If it encounters an error before the end of the directory,
-	// ReadDir returns the DirEntry list read until that point and a non-nil error.
-	ReadDir(n int) ([]DirEntry, error)
-}
-
-// Generic file system errors.
-// Errors returned by file systems can be tested against these errors
-// using errors.Is.
-var (
-	ErrInvalid    = errInvalid()    // "invalid argument"
-	ErrPermission = errPermission() // "permission denied"
-	ErrExist      = errExist()      // "file already exists"
-	ErrNotExist   = errNotExist()   // "file does not exist"
-	ErrClosed     = errClosed()     // "file already closed"
-)
-
-func errInvalid() error    { return oserror.ErrInvalid }
-func errPermission() error { return oserror.ErrPermission }
-func errExist() error      { return oserror.ErrExist }
-func errNotExist() error   { return oserror.ErrNotExist }
-func errClosed() error     { return oserror.ErrClosed }
-
-// A FileInfo describes a file and is returned by Stat.
-type FileInfo interface {
-	Name() string       // base name of the file
-	Size() int64        // length in bytes for regular files; system-dependent for others
-	Mode() FileMode     // file mode bits
-	ModTime() time.Time // modification time
-	IsDir() bool        // abbreviation for Mode().IsDir()
-	Sys() any           // underlying data source (can return nil)
-}
-
-// A FileMode represents a file's mode and permission bits.
-// The bits have the same definition on all systems, so that
-// information about files can be moved from one system
-// to another portably. Not all bits apply to all systems.
-// The only required bit is ModeDir for directories.
-type FileMode uint32
-
-// The defined file mode bits are the most significant bits of the FileMode.
-// The nine least-significant bits are the standard Unix rwxrwxrwx permissions.
-// The values of these bits should be considered part of the public API and
-// may be used in wire protocols or disk representations: they must not be
-// changed, although new bits might be added.
-const (
-	// The single letters are the abbreviations
-	// used by the String method's formatting.
-	ModeDir        FileMode = 1 << (32 - 1 - iota) // d: is a directory
-	ModeAppend                                     // a: append-only
-	ModeExclusive                                  // l: exclusive use
-	ModeTemporary                                  // T: temporary file; Plan 9 only
-	ModeSymlink                                    // L: symbolic link
-	ModeDevice                                     // D: device file
-	ModeNamedPipe                                  // p: named pipe (FIFO)
-	ModeSocket                                     // S: Unix domain socket
-	ModeSetuid                                     // u: setuid
-	ModeSetgid                                     // g: setgid
-	ModeCharDevice                                 // c: Unix character device, when ModeDevice is set
-	ModeSticky                                     // t: sticky
-	ModeIrregular                                  // ?: non-regular file; nothing else is known about this file
-
-	// Mask for the type bits. For regular files, none will be set.
-	ModeType = ModeDir | ModeSymlink | ModeNamedPipe | ModeSocket | ModeDevice | ModeCharDevice | ModeIrregular
-
-	ModePerm FileMode = 0777 // Unix permission bits
-)
-
-func (m FileMode) String() string {
-	const str = "dalTLDpSugct?"
-	var buf [32]byte // Mode is uint32.
-	w := 0
-	for i, c := range str {
-		if m&(1<<uint(32-1-i)) != 0 {
-			buf[w] = byte(c)
-			w++
-		}
-	}
-	if w == 0 {
-		buf[w] = '-'
-		w++
-	}
-	const rwx = "rwxrwxrwx"
-	for i, c := range rwx {
-		if m&(1<<uint(9-1-i)) != 0 {
-			buf[w] = byte(c)
-		} else {
-			buf[w] = '-'
-		}
-		w++
-	}
-	return string(buf[:w])
-}
-
-// IsDir reports whether m describes a directory.
-// That is, it tests for the ModeDir bit being set in m.
-func (m FileMode) IsDir() bool {
-	return m&ModeDir != 0
-}
-
-// IsRegular reports whether m describes a regular file.
-// That is, it tests that no mode type bits are set.
-func (m FileMode) IsRegular() bool {
-	return m&ModeType == 0
-}
-
-// Perm returns the Unix permission bits in m (m & ModePerm).
-func (m FileMode) Perm() FileMode {
-	return m & ModePerm
-}
-
-// Type returns type bits in m (m & ModeType).
-func (m FileMode) Type() FileMode {
-	return m & ModeType
-}
-
-// PathError records an error and the operation and file path that caused it.
-type PathError struct {
-	Op   string
-	Path string
-	Err  error
-}
-
-func (e *PathError) Error() string { return e.Op + " " + e.Path + ": " + e.Err.Error() }
-
-func (e *PathError) Unwrap() error { return e.Err }
-
-// Timeout reports whether this error represents a timeout.
-func (e *PathError) Timeout() bool {
-	t, ok := e.Err.(interface{ Timeout() bool })
-	return ok && t.Timeout()
-}
diff --git a/contrib/go/_std_1.18/src/io/fs/walk.go b/contrib/go/_std_1.18/src/io/fs/walk.go
deleted file mode 100644
index 534876bad3..0000000000
--- a/contrib/go/_std_1.18/src/io/fs/walk.go
+++ /dev/null
@@ -1,127 +0,0 @@
-// Copyright 2020 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package fs
-
-import (
-	"errors"
-	"path"
-)
-
-// SkipDir is used as a return value from WalkDirFuncs to indicate that
-// the directory named in the call is to be skipped. It is not returned
-// as an error by any function.
-var SkipDir = errors.New("skip this directory")
-
-// WalkDirFunc is the type of the function called by WalkDir to visit
-// each file or directory.
-//
-// The path argument contains the argument to WalkDir as a prefix.
-// That is, if WalkDir is called with root argument "dir" and finds a file
-// named "a" in that directory, the walk function will be called with
-// argument "dir/a".
-//
-// The d argument is the fs.DirEntry for the named path.
-//
-// The error result returned by the function controls how WalkDir
-// continues. If the function returns the special value SkipDir, WalkDir
-// skips the current directory (path if d.IsDir() is true, otherwise
-// path's parent directory). Otherwise, if the function returns a non-nil
-// error, WalkDir stops entirely and returns that error.
-//
-// The err argument reports an error related to path, signaling that
-// WalkDir will not walk into that directory. The function can decide how
-// to handle that error; as described earlier, returning the error will
-// cause WalkDir to stop walking the entire tree.
-//
-// WalkDir calls the function with a non-nil err argument in two cases.
-//
-// First, if the initial fs.Stat on the root directory fails, WalkDir
-// calls the function with path set to root, d set to nil, and err set to
-// the error from fs.Stat.
-//
-// Second, if a directory's ReadDir method fails, WalkDir calls the
-// function with path set to the directory's path, d set to an
-// fs.DirEntry describing the directory, and err set to the error from
-// ReadDir. In this second case, the function is called twice with the
-// path of the directory: the first call is before the directory read is
-// attempted and has err set to nil, giving the function a chance to
-// return SkipDir and avoid the ReadDir entirely. The second call is
-// after a failed ReadDir and reports the error from ReadDir.
-// (If ReadDir succeeds, there is no second call.)
-//
-// The differences between WalkDirFunc compared to filepath.WalkFunc are:
-//
-//   - The second argument has type fs.DirEntry instead of fs.FileInfo.
-//   - The function is called before reading a directory, to allow SkipDir
-//     to bypass the directory read entirely.
-//   - If a directory read fails, the function is called a second time
-//     for that directory to report the error.
-//
-type WalkDirFunc func(path string, d DirEntry, err error) error
-
-// walkDir recursively descends path, calling walkDirFn.
-func walkDir(fsys FS, name string, d DirEntry, walkDirFn WalkDirFunc) error {
-	if err := walkDirFn(name, d, nil); err != nil || !d.IsDir() {
-		if err == SkipDir && d.IsDir() {
-			// Successfully skipped directory.
-			err = nil
-		}
-		return err
-	}
-
-	dirs, err := ReadDir(fsys, name)
-	if err != nil {
-		// Second call, to report ReadDir error.
-		err = walkDirFn(name, d, err)
-		if err != nil {
-			return err
-		}
-	}
-
-	for _, d1 := range dirs {
-		name1 := path.Join(name, d1.Name())
-		if err := walkDir(fsys, name1, d1, walkDirFn); err != nil {
-			if err == SkipDir {
-				break
-			}
-			return err
-		}
-	}
-	return nil
-}
-
-// WalkDir walks the file tree rooted at root, calling fn for each file or
-// directory in the tree, including root.
-//
-// All errors that arise visiting files and directories are filtered by fn:
-// see the fs.WalkDirFunc documentation for details.
-//
-// The files are walked in lexical order, which makes the output deterministic
-// but requires WalkDir to read an entire directory into memory before proceeding
-// to walk that directory.
-//
-// WalkDir does not follow symbolic links found in directories,
-// but if root itself is a symbolic link, its target will be walked.
-func WalkDir(fsys FS, root string, fn WalkDirFunc) error {
-	info, err := Stat(fsys, root)
-	if err != nil {
-		err = fn(root, nil, err)
-	} else {
-		err = walkDir(fsys, root, &statDirEntry{info}, fn)
-	}
-	if err == SkipDir {
-		return nil
-	}
-	return err
-}
-
-type statDirEntry struct {
-	info FileInfo
-}
-
-func (d *statDirEntry) Name() string            { return d.info.Name() }
-func (d *statDirEntry) IsDir() bool             { return d.info.IsDir() }
-func (d *statDirEntry) Type() FileMode          { return d.info.Mode().Type() }
-func (d *statDirEntry) Info() (FileInfo, error) { return d.info, nil }
diff --git a/contrib/go/_std_1.18/src/io/io.go b/contrib/go/_std_1.18/src/io/io.go
deleted file mode 100644
index 1ea01d5d63..0000000000
--- a/contrib/go/_std_1.18/src/io/io.go
+++ /dev/null
@@ -1,654 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package io provides basic interfaces to I/O primitives.
-// Its primary job is to wrap existing implementations of such primitives,
-// such as those in package os, into shared public interfaces that
-// abstract the functionality, plus some other related primitives.
-//
-// Because these interfaces and primitives wrap lower-level operations with
-// various implementations, unless otherwise informed clients should not
-// assume they are safe for parallel execution.
-package io
-
-import (
-	"errors"
-	"sync"
-)
-
-// Seek whence values.
-const (
-	SeekStart   = 0 // seek relative to the origin of the file
-	SeekCurrent = 1 // seek relative to the current offset
-	SeekEnd     = 2 // seek relative to the end
-)
-
-// ErrShortWrite means that a write accepted fewer bytes than requested
-// but failed to return an explicit error.
-var ErrShortWrite = errors.New("short write")
-
-// errInvalidWrite means that a write returned an impossible count.
-var errInvalidWrite = errors.New("invalid write result")
-
-// ErrShortBuffer means that a read required a longer buffer than was provided.
-var ErrShortBuffer = errors.New("short buffer")
-
-// EOF is the error returned by Read when no more input is available.
-// (Read must return EOF itself, not an error wrapping EOF,
-// because callers will test for EOF using ==.)
-// Functions should return EOF only to signal a graceful end of input.
-// If the EOF occurs unexpectedly in a structured data stream,
-// the appropriate error is either ErrUnexpectedEOF or some other error
-// giving more detail.
-var EOF = errors.New("EOF")
-
-// ErrUnexpectedEOF means that EOF was encountered in the
-// middle of reading a fixed-size block or data structure.
-var ErrUnexpectedEOF = errors.New("unexpected EOF")
-
-// ErrNoProgress is returned by some clients of a Reader when
-// many calls to Read have failed to return any data or error,
-// usually the sign of a broken Reader implementation.
-var ErrNoProgress = errors.New("multiple Read calls return no data or error")
-
-// Reader is the interface that wraps the basic Read method.
-//
-// Read reads up to len(p) bytes into p. It returns the number of bytes
-// read (0 <= n <= len(p)) and any error encountered. Even if Read
-// returns n < len(p), it may use all of p as scratch space during the call.
-// If some data is available but not len(p) bytes, Read conventionally
-// returns what is available instead of waiting for more.
-//
-// When Read encounters an error or end-of-file condition after
-// successfully reading n > 0 bytes, it returns the number of
-// bytes read. It may return the (non-nil) error from the same call
-// or return the error (and n == 0) from a subsequent call.
-// An instance of this general case is that a Reader returning
-// a non-zero number of bytes at the end of the input stream may
-// return either err == EOF or err == nil. The next Read should
-// return 0, EOF.
-//
-// Callers should always process the n > 0 bytes returned before
-// considering the error err. Doing so correctly handles I/O errors
-// that happen after reading some bytes and also both of the
-// allowed EOF behaviors.
-//
-// Implementations of Read are discouraged from returning a
-// zero byte count with a nil error, except when len(p) == 0.
-// Callers should treat a return of 0 and nil as indicating that
-// nothing happened; in particular it does not indicate EOF.
-//
-// Implementations must not retain p.
-type Reader interface {
-	Read(p []byte) (n int, err error)
-}
-
-// Writer is the interface that wraps the basic Write method.
-//
-// Write writes len(p) bytes from p to the underlying data stream.
-// It returns the number of bytes written from p (0 <= n <= len(p))
-// and any error encountered that caused the write to stop early.
-// Write must return a non-nil error if it returns n < len(p).
-// Write must not modify the slice data, even temporarily.
-//
-// Implementations must not retain p.
-type Writer interface {
-	Write(p []byte) (n int, err error)
-}
-
-// Closer is the interface that wraps the basic Close method.
-//
-// The behavior of Close after the first call is undefined.
-// Specific implementations may document their own behavior.
-type Closer interface {
-	Close() error
-}
-
-// Seeker is the interface that wraps the basic Seek method.
-//
-// Seek sets the offset for the next Read or Write to offset,
-// interpreted according to whence:
-// SeekStart means relative to the start of the file,
-// SeekCurrent means relative to the current offset, and
-// SeekEnd means relative to the end.
-// Seek returns the new offset relative to the start of the
-// file or an error, if any.
-//
-// Seeking to an offset before the start of the file is an error.
-// Seeking to any positive offset may be allowed, but if the new offset exceeds
-// the size of the underlying object the behavior of subsequent I/O operations
-// is implementation-dependent.
-type Seeker interface {
-	Seek(offset int64, whence int) (int64, error)
-}
-
-// ReadWriter is the interface that groups the basic Read and Write methods.
-type ReadWriter interface {
-	Reader
-	Writer
-}
-
-// ReadCloser is the interface that groups the basic Read and Close methods.
-type ReadCloser interface {
-	Reader
-	Closer
-}
-
-// WriteCloser is the interface that groups the basic Write and Close methods.
-type WriteCloser interface {
-	Writer
-	Closer
-}
-
-// ReadWriteCloser is the interface that groups the basic Read, Write and Close methods.
-type ReadWriteCloser interface {
-	Reader
-	Writer
-	Closer
-}
-
-// ReadSeeker is the interface that groups the basic Read and Seek methods.
-type ReadSeeker interface {
-	Reader
-	Seeker
-}
-
-// ReadSeekCloser is the interface that groups the basic Read, Seek and Close
-// methods.
-type ReadSeekCloser interface {
-	Reader
-	Seeker
-	Closer
-}
-
-// WriteSeeker is the interface that groups the basic Write and Seek methods.
-type WriteSeeker interface {
-	Writer
-	Seeker
-}
-
-// ReadWriteSeeker is the interface that groups the basic Read, Write and Seek methods.
-type ReadWriteSeeker interface {
-	Reader
-	Writer
-	Seeker
-}
-
-// ReaderFrom is the interface that wraps the ReadFrom method.
-//
-// ReadFrom reads data from r until EOF or error.
-// The return value n is the number of bytes read.
-// Any error except EOF encountered during the read is also returned.
-//
-// The Copy function uses ReaderFrom if available.
-type ReaderFrom interface {
-	ReadFrom(r Reader) (n int64, err error)
-}
-
-// WriterTo is the interface that wraps the WriteTo method.
-//
-// WriteTo writes data to w until there's no more data to write or
-// when an error occurs. The return value n is the number of bytes
-// written. Any error encountered during the write is also returned.
-//
-// The Copy function uses WriterTo if available.
-type WriterTo interface {
-	WriteTo(w Writer) (n int64, err error)
-}
-
-// ReaderAt is the interface that wraps the basic ReadAt method.
-//
-// ReadAt reads len(p) bytes into p starting at offset off in the
-// underlying input source. It returns the number of bytes
-// read (0 <= n <= len(p)) and any error encountered.
-//
-// When ReadAt returns n < len(p), it returns a non-nil error
-// explaining why more bytes were not returned. In this respect,
-// ReadAt is stricter than Read.
-//
-// Even if ReadAt returns n < len(p), it may use all of p as scratch
-// space during the call. If some data is available but not len(p) bytes,
-// ReadAt blocks until either all the data is available or an error occurs.
-// In this respect ReadAt is different from Read.
-//
-// If the n = len(p) bytes returned by ReadAt are at the end of the
-// input source, ReadAt may return either err == EOF or err == nil.
-//
-// If ReadAt is reading from an input source with a seek offset,
-// ReadAt should not affect nor be affected by the underlying
-// seek offset.
-//
-// Clients of ReadAt can execute parallel ReadAt calls on the
-// same input source.
-//
-// Implementations must not retain p.
-type ReaderAt interface {
-	ReadAt(p []byte, off int64) (n int, err error)
-}
-
-// WriterAt is the interface that wraps the basic WriteAt method.
-//
-// WriteAt writes len(p) bytes from p to the underlying data stream
-// at offset off. It returns the number of bytes written from p (0 <= n <= len(p))
-// and any error encountered that caused the write to stop early.
-// WriteAt must return a non-nil error if it returns n < len(p).
-//
-// If WriteAt is writing to a destination with a seek offset,
-// WriteAt should not affect nor be affected by the underlying
-// seek offset.
-//
-// Clients of WriteAt can execute parallel WriteAt calls on the same
-// destination if the ranges do not overlap.
-//
-// Implementations must not retain p.
-type WriterAt interface {
-	WriteAt(p []byte, off int64) (n int, err error)
-}
-
-// ByteReader is the interface that wraps the ReadByte method.
-//
-// ReadByte reads and returns the next byte from the input or
-// any error encountered. If ReadByte returns an error, no input
-// byte was consumed, and the returned byte value is undefined.
-//
-// ReadByte provides an efficient interface for byte-at-time
-// processing. A Reader that does not implement  ByteReader
-// can be wrapped using bufio.NewReader to add this method.
-type ByteReader interface {
-	ReadByte() (byte, error)
-}
-
-// ByteScanner is the interface that adds the UnreadByte method to the
-// basic ReadByte method.
-//
-// UnreadByte causes the next call to ReadByte to return the last byte read.
-// If the last operation was not a successful call to ReadByte, UnreadByte may
-// return an error, unread the last byte read (or the byte prior to the
-// last-unread byte), or (in implementations that support the Seeker interface)
-// seek to one byte before the current offset.
-type ByteScanner interface {
-	ByteReader
-	UnreadByte() error
-}
-
-// ByteWriter is the interface that wraps the WriteByte method.
-type ByteWriter interface {
-	WriteByte(c byte) error
-}
-
-// RuneReader is the interface that wraps the ReadRune method.
-//
-// ReadRune reads a single encoded Unicode character
-// and returns the rune and its size in bytes. If no character is
-// available, err will be set.
-type RuneReader interface {
-	ReadRune() (r rune, size int, err error)
-}
-
-// RuneScanner is the interface that adds the UnreadRune method to the
-// basic ReadRune method.
-//
-// UnreadRune causes the next call to ReadRune to return the last rune read.
-// If the last operation was not a successful call to ReadRune, UnreadRune may
-// return an error, unread the last rune read (or the rune prior to the
-// last-unread rune), or (in implementations that support the Seeker interface)
-// seek to the start of the rune before the current offset.
-type RuneScanner interface {
-	RuneReader
-	UnreadRune() error
-}
-
-// StringWriter is the interface that wraps the WriteString method.
-type StringWriter interface {
-	WriteString(s string) (n int, err error)
-}
-
-// WriteString writes the contents of the string s to w, which accepts a slice of bytes.
-// If w implements StringWriter, its WriteString method is invoked directly.
-// Otherwise, w.Write is called exactly once.
-func WriteString(w Writer, s string) (n int, err error) {
-	if sw, ok := w.(StringWriter); ok {
-		return sw.WriteString(s)
-	}
-	return w.Write([]byte(s))
-}
-
-// ReadAtLeast reads from r into buf until it has read at least min bytes.
-// It returns the number of bytes copied and an error if fewer bytes were read.
-// The error is EOF only if no bytes were read.
-// If an EOF happens after reading fewer than min bytes,
-// ReadAtLeast returns ErrUnexpectedEOF.
-// If min is greater than the length of buf, ReadAtLeast returns ErrShortBuffer.
-// On return, n >= min if and only if err == nil.
-// If r returns an error having read at least min bytes, the error is dropped.
-func ReadAtLeast(r Reader, buf []byte, min int) (n int, err error) {
-	if len(buf) < min {
-		return 0, ErrShortBuffer
-	}
-	for n < min && err == nil {
-		var nn int
-		nn, err = r.Read(buf[n:])
-		n += nn
-	}
-	if n >= min {
-		err = nil
-	} else if n > 0 && err == EOF {
-		err = ErrUnexpectedEOF
-	}
-	return
-}
-
-// ReadFull reads exactly len(buf) bytes from r into buf.
-// It returns the number of bytes copied and an error if fewer bytes were read.
-// The error is EOF only if no bytes were read.
-// If an EOF happens after reading some but not all the bytes,
-// ReadFull returns ErrUnexpectedEOF.
-// On return, n == len(buf) if and only if err == nil.
-// If r returns an error having read at least len(buf) bytes, the error is dropped.
-func ReadFull(r Reader, buf []byte) (n int, err error) {
-	return ReadAtLeast(r, buf, len(buf))
-}
-
-// CopyN copies n bytes (or until an error) from src to dst.
-// It returns the number of bytes copied and the earliest
-// error encountered while copying.
-// On return, written == n if and only if err == nil.
-//
-// If dst implements the ReaderFrom interface,
-// the copy is implemented using it.
-func CopyN(dst Writer, src Reader, n int64) (written int64, err error) {
-	written, err = Copy(dst, LimitReader(src, n))
-	if written == n {
-		return n, nil
-	}
-	if written < n && err == nil {
-		// src stopped early; must have been EOF.
-		err = EOF
-	}
-	return
-}
-
-// Copy copies from src to dst until either EOF is reached
-// on src or an error occurs. It returns the number of bytes
-// copied and the first error encountered while copying, if any.
-//
-// A successful Copy returns err == nil, not err == EOF.
-// Because Copy is defined to read from src until EOF, it does
-// not treat an EOF from Read as an error to be reported.
-//
-// If src implements the WriterTo interface,
-// the copy is implemented by calling src.WriteTo(dst).
-// Otherwise, if dst implements the ReaderFrom interface,
-// the copy is implemented by calling dst.ReadFrom(src).
-func Copy(dst Writer, src Reader) (written int64, err error) {
-	return copyBuffer(dst, src, nil)
-}
-
-// CopyBuffer is identical to Copy except that it stages through the
-// provided buffer (if one is required) rather than allocating a
-// temporary one. If buf is nil, one is allocated; otherwise if it has
-// zero length, CopyBuffer panics.
-//
-// If either src implements WriterTo or dst implements ReaderFrom,
-// buf will not be used to perform the copy.
-func CopyBuffer(dst Writer, src Reader, buf []byte) (written int64, err error) {
-	if buf != nil && len(buf) == 0 {
-		panic("empty buffer in CopyBuffer")
-	}
-	return copyBuffer(dst, src, buf)
-}
-
-// copyBuffer is the actual implementation of Copy and CopyBuffer.
-// if buf is nil, one is allocated.
-func copyBuffer(dst Writer, src Reader, buf []byte) (written int64, err error) {
-	// If the reader has a WriteTo method, use it to do the copy.
-	// Avoids an allocation and a copy.
-	if wt, ok := src.(WriterTo); ok {
-		return wt.WriteTo(dst)
-	}
-	// Similarly, if the writer has a ReadFrom method, use it to do the copy.
-	if rt, ok := dst.(ReaderFrom); ok {
-		return rt.ReadFrom(src)
-	}
-	if buf == nil {
-		size := 32 * 1024
-		if l, ok := src.(*LimitedReader); ok && int64(size) > l.N {
-			if l.N < 1 {
-				size = 1
-			} else {
-				size = int(l.N)
-			}
-		}
-		buf = make([]byte, size)
-	}
-	for {
-		nr, er := src.Read(buf)
-		if nr > 0 {
-			nw, ew := dst.Write(buf[0:nr])
-			if nw < 0 || nr < nw {
-				nw = 0
-				if ew == nil {
-					ew = errInvalidWrite
-				}
-			}
-			written += int64(nw)
-			if ew != nil {
-				err = ew
-				break
-			}
-			if nr != nw {
-				err = ErrShortWrite
-				break
-			}
-		}
-		if er != nil {
-			if er != EOF {
-				err = er
-			}
-			break
-		}
-	}
-	return written, err
-}
-
-// LimitReader returns a Reader that reads from r
-// but stops with EOF after n bytes.
-// The underlying implementation is a *LimitedReader.
-func LimitReader(r Reader, n int64) Reader { return &LimitedReader{r, n} }
-
-// A LimitedReader reads from R but limits the amount of
-// data returned to just N bytes. Each call to Read
-// updates N to reflect the new amount remaining.
-// Read returns EOF when N <= 0 or when the underlying R returns EOF.
-type LimitedReader struct {
-	R Reader // underlying reader
-	N int64  // max bytes remaining
-}
-
-func (l *LimitedReader) Read(p []byte) (n int, err error) {
-	if l.N <= 0 {
-		return 0, EOF
-	}
-	if int64(len(p)) > l.N {
-		p = p[0:l.N]
-	}
-	n, err = l.R.Read(p)
-	l.N -= int64(n)
-	return
-}
-
-// NewSectionReader returns a SectionReader that reads from r
-// starting at offset off and stops with EOF after n bytes.
-func NewSectionReader(r ReaderAt, off int64, n int64) *SectionReader {
-	var remaining int64
-	const maxint64 = 1<<63 - 1
-	if off <= maxint64-n {
-		remaining = n + off
-	} else {
-		// Overflow, with no way to return error.
-		// Assume we can read up to an offset of 1<<63 - 1.
-		remaining = maxint64
-	}
-	return &SectionReader{r, off, off, remaining}
-}
-
-// SectionReader implements Read, Seek, and ReadAt on a section
-// of an underlying ReaderAt.
-type SectionReader struct {
-	r     ReaderAt
-	base  int64
-	off   int64
-	limit int64
-}
-
-func (s *SectionReader) Read(p []byte) (n int, err error) {
-	if s.off >= s.limit {
-		return 0, EOF
-	}
-	if max := s.limit - s.off; int64(len(p)) > max {
-		p = p[0:max]
-	}
-	n, err = s.r.ReadAt(p, s.off)
-	s.off += int64(n)
-	return
-}
-
-var errWhence = errors.New("Seek: invalid whence")
-var errOffset = errors.New("Seek: invalid offset")
-
-func (s *SectionReader) Seek(offset int64, whence int) (int64, error) {
-	switch whence {
-	default:
-		return 0, errWhence
-	case SeekStart:
-		offset += s.base
-	case SeekCurrent:
-		offset += s.off
-	case SeekEnd:
-		offset += s.limit
-	}
-	if offset < s.base {
-		return 0, errOffset
-	}
-	s.off = offset
-	return offset - s.base, nil
-}
-
-func (s *SectionReader) ReadAt(p []byte, off int64) (n int, err error) {
-	if off < 0 || off >= s.limit-s.base {
-		return 0, EOF
-	}
-	off += s.base
-	if max := s.limit - off; int64(len(p)) > max {
-		p = p[0:max]
-		n, err = s.r.ReadAt(p, off)
-		if err == nil {
-			err = EOF
-		}
-		return n, err
-	}
-	return s.r.ReadAt(p, off)
-}
-
-// Size returns the size of the section in bytes.
-func (s *SectionReader) Size() int64 { return s.limit - s.base }
-
-// TeeReader returns a Reader that writes to w what it reads from r.
-// All reads from r performed through it are matched with
-// corresponding writes to w. There is no internal buffering -
-// the write must complete before the read completes.
-// Any error encountered while writing is reported as a read error.
-func TeeReader(r Reader, w Writer) Reader {
-	return &teeReader{r, w}
-}
-
-type teeReader struct {
-	r Reader
-	w Writer
-}
-
-func (t *teeReader) Read(p []byte) (n int, err error) {
-	n, err = t.r.Read(p)
-	if n > 0 {
-		if n, err := t.w.Write(p[:n]); err != nil {
-			return n, err
-		}
-	}
-	return
-}
-
-// Discard is a Writer on which all Write calls succeed
-// without doing anything.
-var Discard Writer = discard{}
-
-type discard struct{}
-
-// discard implements ReaderFrom as an optimization so Copy to
-// io.Discard can avoid doing unnecessary work.
-var _ ReaderFrom = discard{}
-
-func (discard) Write(p []byte) (int, error) {
-	return len(p), nil
-}
-
-func (discard) WriteString(s string) (int, error) {
-	return len(s), nil
-}
-
-var blackHolePool = sync.Pool{
-	New: func() any {
-		b := make([]byte, 8192)
-		return &b
-	},
-}
-
-func (discard) ReadFrom(r Reader) (n int64, err error) {
-	bufp := blackHolePool.Get().(*[]byte)
-	readSize := 0
-	for {
-		readSize, err = r.Read(*bufp)
-		n += int64(readSize)
-		if err != nil {
-			blackHolePool.Put(bufp)
-			if err == EOF {
-				return n, nil
-			}
-			return
-		}
-	}
-}
-
-// NopCloser returns a ReadCloser with a no-op Close method wrapping
-// the provided Reader r.
-func NopCloser(r Reader) ReadCloser {
-	return nopCloser{r}
-}
-
-type nopCloser struct {
-	Reader
-}
-
-func (nopCloser) Close() error { return nil }
-
-// ReadAll reads from r until an error or EOF and returns the data it read.
-// A successful call returns err == nil, not err == EOF. Because ReadAll is
-// defined to read from src until EOF, it does not treat an EOF from Read
-// as an error to be reported.
-func ReadAll(r Reader) ([]byte, error) {
-	b := make([]byte, 0, 512)
-	for {
-		if len(b) == cap(b) {
-			// Add more capacity (let append pick how much).
-			b = append(b, 0)[:len(b)]
-		}
-		n, err := r.Read(b[len(b):cap(b)])
-		b = b[:len(b)+n]
-		if err != nil {
-			if err == EOF {
-				err = nil
-			}
-			return b, err
-		}
-	}
-}
diff --git a/contrib/go/_std_1.18/src/io/ioutil/ioutil.go b/contrib/go/_std_1.18/src/io/ioutil/ioutil.go
deleted file mode 100644
index 45682b89c9..0000000000
--- a/contrib/go/_std_1.18/src/io/ioutil/ioutil.go
+++ /dev/null
@@ -1,84 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package ioutil implements some I/O utility functions.
-//
-// As of Go 1.16, the same functionality is now provided
-// by package io or package os, and those implementations
-// should be preferred in new code.
-// See the specific function documentation for details.
-package ioutil
-
-import (
-	"io"
-	"io/fs"
-	"os"
-	"sort"
-)
-
-// ReadAll reads from r until an error or EOF and returns the data it read.
-// A successful call returns err == nil, not err == EOF. Because ReadAll is
-// defined to read from src until EOF, it does not treat an EOF from Read
-// as an error to be reported.
-//
-// As of Go 1.16, this function simply calls io.ReadAll.
-func ReadAll(r io.Reader) ([]byte, error) {
-	return io.ReadAll(r)
-}
-
-// ReadFile reads the file named by filename and returns the contents.
-// A successful call returns err == nil, not err == EOF. Because ReadFile
-// reads the whole file, it does not treat an EOF from Read as an error
-// to be reported.
-//
-// As of Go 1.16, this function simply calls os.ReadFile.
-func ReadFile(filename string) ([]byte, error) {
-	return os.ReadFile(filename)
-}
-
-// WriteFile writes data to a file named by filename.
-// If the file does not exist, WriteFile creates it with permissions perm
-// (before umask); otherwise WriteFile truncates it before writing, without changing permissions.
-//
-// As of Go 1.16, this function simply calls os.WriteFile.
-func WriteFile(filename string, data []byte, perm fs.FileMode) error {
-	return os.WriteFile(filename, data, perm)
-}
-
-// ReadDir reads the directory named by dirname and returns
-// a list of fs.FileInfo for the directory's contents,
-// sorted by filename. If an error occurs reading the directory,
-// ReadDir returns no directory entries along with the error.
-//
-// As of Go 1.16, os.ReadDir is a more efficient and correct choice:
-// it returns a list of fs.DirEntry instead of fs.FileInfo,
-// and it returns partial results in the case of an error
-// midway through reading a directory.
-func ReadDir(dirname string) ([]fs.FileInfo, error) {
-	f, err := os.Open(dirname)
-	if err != nil {
-		return nil, err
-	}
-	list, err := f.Readdir(-1)
-	f.Close()
-	if err != nil {
-		return nil, err
-	}
-	sort.Slice(list, func(i, j int) bool { return list[i].Name() < list[j].Name() })
-	return list, nil
-}
-
-// NopCloser returns a ReadCloser with a no-op Close method wrapping
-// the provided Reader r.
-//
-// As of Go 1.16, this function simply calls io.NopCloser.
-func NopCloser(r io.Reader) io.ReadCloser {
-	return io.NopCloser(r)
-}
-
-// Discard is an io.Writer on which all Write calls succeed
-// without doing anything.
-//
-// As of Go 1.16, this value is simply io.Discard.
-var Discard io.Writer = io.Discard
diff --git a/contrib/go/_std_1.18/src/io/ioutil/tempfile.go b/contrib/go/_std_1.18/src/io/ioutil/tempfile.go
deleted file mode 100644
index c43db2c080..0000000000
--- a/contrib/go/_std_1.18/src/io/ioutil/tempfile.go
+++ /dev/null
@@ -1,41 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package ioutil
-
-import (
-	"os"
-)
-
-// TempFile creates a new temporary file in the directory dir,
-// opens the file for reading and writing, and returns the resulting *os.File.
-// The filename is generated by taking pattern and adding a random
-// string to the end. If pattern includes a "*", the random string
-// replaces the last "*".
-// If dir is the empty string, TempFile uses the default directory
-// for temporary files (see os.TempDir).
-// Multiple programs calling TempFile simultaneously
-// will not choose the same file. The caller can use f.Name()
-// to find the pathname of the file. It is the caller's responsibility
-// to remove the file when no longer needed.
-//
-// As of Go 1.17, this function simply calls os.CreateTemp.
-func TempFile(dir, pattern string) (f *os.File, err error) {
-	return os.CreateTemp(dir, pattern)
-}
-
-// TempDir creates a new temporary directory in the directory dir.
-// The directory name is generated by taking pattern and applying a
-// random string to the end. If pattern includes a "*", the random string
-// replaces the last "*". TempDir returns the name of the new directory.
-// If dir is the empty string, TempDir uses the
-// default directory for temporary files (see os.TempDir).
-// Multiple programs calling TempDir simultaneously
-// will not choose the same directory. It is the caller's responsibility
-// to remove the directory when no longer needed.
-//
-// As of Go 1.17, this function simply calls os.MkdirTemp.
-func TempDir(dir, pattern string) (name string, err error) {
-	return os.MkdirTemp(dir, pattern)
-}
diff --git a/contrib/go/_std_1.18/src/io/multi.go b/contrib/go/_std_1.18/src/io/multi.go
deleted file mode 100644
index 24ee71e4ca..0000000000
--- a/contrib/go/_std_1.18/src/io/multi.go
+++ /dev/null
@@ -1,112 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package io
-
-type eofReader struct{}
-
-func (eofReader) Read([]byte) (int, error) {
-	return 0, EOF
-}
-
-type multiReader struct {
-	readers []Reader
-}
-
-func (mr *multiReader) Read(p []byte) (n int, err error) {
-	for len(mr.readers) > 0 {
-		// Optimization to flatten nested multiReaders (Issue 13558).
-		if len(mr.readers) == 1 {
-			if r, ok := mr.readers[0].(*multiReader); ok {
-				mr.readers = r.readers
-				continue
-			}
-		}
-		n, err = mr.readers[0].Read(p)
-		if err == EOF {
-			// Use eofReader instead of nil to avoid nil panic
-			// after performing flatten (Issue 18232).
-			mr.readers[0] = eofReader{} // permit earlier GC
-			mr.readers = mr.readers[1:]
-		}
-		if n > 0 || err != EOF {
-			if err == EOF && len(mr.readers) > 0 {
-				// Don't return EOF yet. More readers remain.
-				err = nil
-			}
-			return
-		}
-	}
-	return 0, EOF
-}
-
-// MultiReader returns a Reader that's the logical concatenation of
-// the provided input readers. They're read sequentially. Once all
-// inputs have returned EOF, Read will return EOF.  If any of the readers
-// return a non-nil, non-EOF error, Read will return that error.
-func MultiReader(readers ...Reader) Reader {
-	r := make([]Reader, len(readers))
-	copy(r, readers)
-	return &multiReader{r}
-}
-
-type multiWriter struct {
-	writers []Writer
-}
-
-func (t *multiWriter) Write(p []byte) (n int, err error) {
-	for _, w := range t.writers {
-		n, err = w.Write(p)
-		if err != nil {
-			return
-		}
-		if n != len(p) {
-			err = ErrShortWrite
-			return
-		}
-	}
-	return len(p), nil
-}
-
-var _ StringWriter = (*multiWriter)(nil)
-
-func (t *multiWriter) WriteString(s string) (n int, err error) {
-	var p []byte // lazily initialized if/when needed
-	for _, w := range t.writers {
-		if sw, ok := w.(StringWriter); ok {
-			n, err = sw.WriteString(s)
-		} else {
-			if p == nil {
-				p = []byte(s)
-			}
-			n, err = w.Write(p)
-		}
-		if err != nil {
-			return
-		}
-		if n != len(s) {
-			err = ErrShortWrite
-			return
-		}
-	}
-	return len(s), nil
-}
-
-// MultiWriter creates a writer that duplicates its writes to all the
-// provided writers, similar to the Unix tee(1) command.
-//
-// Each write is written to each listed writer, one at a time.
-// If a listed writer returns an error, that overall write operation
-// stops and returns the error; it does not continue down the list.
-func MultiWriter(writers ...Writer) Writer {
-	allWriters := make([]Writer, 0, len(writers))
-	for _, w := range writers {
-		if mw, ok := w.(*multiWriter); ok {
-			allWriters = append(allWriters, mw.writers...)
-		} else {
-			allWriters = append(allWriters, w)
-		}
-	}
-	return &multiWriter{allWriters}
-}
diff --git a/contrib/go/_std_1.18/src/log/log.go b/contrib/go/_std_1.18/src/log/log.go
deleted file mode 100644
index 5e79b19522..0000000000
--- a/contrib/go/_std_1.18/src/log/log.go
+++ /dev/null
@@ -1,411 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package log implements a simple logging package. It defines a type, Logger,
-// with methods for formatting output. It also has a predefined 'standard'
-// Logger accessible through helper functions Print[f|ln], Fatal[f|ln], and
-// Panic[f|ln], which are easier to use than creating a Logger manually.
-// That logger writes to standard error and prints the date and time
-// of each logged message.
-// Every log message is output on a separate line: if the message being
-// printed does not end in a newline, the logger will add one.
-// The Fatal functions call os.Exit(1) after writing the log message.
-// The Panic functions call panic after writing the log message.
-package log
-
-import (
-	"fmt"
-	"io"
-	"os"
-	"runtime"
-	"sync"
-	"sync/atomic"
-	"time"
-)
-
-// These flags define which text to prefix to each log entry generated by the Logger.
-// Bits are or'ed together to control what's printed.
-// With the exception of the Lmsgprefix flag, there is no
-// control over the order they appear (the order listed here)
-// or the format they present (as described in the comments).
-// The prefix is followed by a colon only when Llongfile or Lshortfile
-// is specified.
-// For example, flags Ldate | Ltime (or LstdFlags) produce,
-//	2009/01/23 01:23:23 message
-// while flags Ldate | Ltime | Lmicroseconds | Llongfile produce,
-//	2009/01/23 01:23:23.123123 /a/b/c/d.go:23: message
-const (
-	Ldate         = 1 << iota     // the date in the local time zone: 2009/01/23
-	Ltime                         // the time in the local time zone: 01:23:23
-	Lmicroseconds                 // microsecond resolution: 01:23:23.123123.  assumes Ltime.
-	Llongfile                     // full file name and line number: /a/b/c/d.go:23
-	Lshortfile                    // final file name element and line number: d.go:23. overrides Llongfile
-	LUTC                          // if Ldate or Ltime is set, use UTC rather than the local time zone
-	Lmsgprefix                    // move the "prefix" from the beginning of the line to before the message
-	LstdFlags     = Ldate | Ltime // initial values for the standard logger
-)
-
-// A Logger represents an active logging object that generates lines of
-// output to an io.Writer. Each logging operation makes a single call to
-// the Writer's Write method. A Logger can be used simultaneously from
-// multiple goroutines; it guarantees to serialize access to the Writer.
-type Logger struct {
-	mu        sync.Mutex // ensures atomic writes; protects the following fields
-	prefix    string     // prefix on each line to identify the logger (but see Lmsgprefix)
-	flag      int        // properties
-	out       io.Writer  // destination for output
-	buf       []byte     // for accumulating text to write
-	isDiscard int32      // atomic boolean: whether out == io.Discard
-}
-
-// New creates a new Logger. The out variable sets the
-// destination to which log data will be written.
-// The prefix appears at the beginning of each generated log line, or
-// after the log header if the Lmsgprefix flag is provided.
-// The flag argument defines the logging properties.
-func New(out io.Writer, prefix string, flag int) *Logger {
-	l := &Logger{out: out, prefix: prefix, flag: flag}
-	if out == io.Discard {
-		l.isDiscard = 1
-	}
-	return l
-}
-
-// SetOutput sets the output destination for the logger.
-func (l *Logger) SetOutput(w io.Writer) {
-	l.mu.Lock()
-	defer l.mu.Unlock()
-	l.out = w
-	isDiscard := int32(0)
-	if w == io.Discard {
-		isDiscard = 1
-	}
-	atomic.StoreInt32(&l.isDiscard, isDiscard)
-}
-
-var std = New(os.Stderr, "", LstdFlags)
-
-// Default returns the standard logger used by the package-level output functions.
-func Default() *Logger { return std }
-
-// Cheap integer to fixed-width decimal ASCII. Give a negative width to avoid zero-padding.
-func itoa(buf *[]byte, i int, wid int) {
-	// Assemble decimal in reverse order.
-	var b [20]byte
-	bp := len(b) - 1
-	for i >= 10 || wid > 1 {
-		wid--
-		q := i / 10
-		b[bp] = byte('0' + i - q*10)
-		bp--
-		i = q
-	}
-	// i < 10
-	b[bp] = byte('0' + i)
-	*buf = append(*buf, b[bp:]...)
-}
-
-// formatHeader writes log header to buf in following order:
-//   * l.prefix (if it's not blank and Lmsgprefix is unset),
-//   * date and/or time (if corresponding flags are provided),
-//   * file and line number (if corresponding flags are provided),
-//   * l.prefix (if it's not blank and Lmsgprefix is set).
-func (l *Logger) formatHeader(buf *[]byte, t time.Time, file string, line int) {
-	if l.flag&Lmsgprefix == 0 {
-		*buf = append(*buf, l.prefix...)
-	}
-	if l.flag&(Ldate|Ltime|Lmicroseconds) != 0 {
-		if l.flag&LUTC != 0 {
-			t = t.UTC()
-		}
-		if l.flag&Ldate != 0 {
-			year, month, day := t.Date()
-			itoa(buf, year, 4)
-			*buf = append(*buf, '/')
-			itoa(buf, int(month), 2)
-			*buf = append(*buf, '/')
-			itoa(buf, day, 2)
-			*buf = append(*buf, ' ')
-		}
-		if l.flag&(Ltime|Lmicroseconds) != 0 {
-			hour, min, sec := t.Clock()
-			itoa(buf, hour, 2)
-			*buf = append(*buf, ':')
-			itoa(buf, min, 2)
-			*buf = append(*buf, ':')
-			itoa(buf, sec, 2)
-			if l.flag&Lmicroseconds != 0 {
-				*buf = append(*buf, '.')
-				itoa(buf, t.Nanosecond()/1e3, 6)
-			}
-			*buf = append(*buf, ' ')
-		}
-	}
-	if l.flag&(Lshortfile|Llongfile) != 0 {
-		if l.flag&Lshortfile != 0 {
-			short := file
-			for i := len(file) - 1; i > 0; i-- {
-				if file[i] == '/' {
-					short = file[i+1:]
-					break
-				}
-			}
-			file = short
-		}
-		*buf = append(*buf, file...)
-		*buf = append(*buf, ':')
-		itoa(buf, line, -1)
-		*buf = append(*buf, ": "...)
-	}
-	if l.flag&Lmsgprefix != 0 {
-		*buf = append(*buf, l.prefix...)
-	}
-}
-
-// Output writes the output for a logging event. The string s contains
-// the text to print after the prefix specified by the flags of the
-// Logger. A newline is appended if the last character of s is not
-// already a newline. Calldepth is used to recover the PC and is
-// provided for generality, although at the moment on all pre-defined
-// paths it will be 2.
-func (l *Logger) Output(calldepth int, s string) error {
-	now := time.Now() // get this early.
-	var file string
-	var line int
-	l.mu.Lock()
-	defer l.mu.Unlock()
-	if l.flag&(Lshortfile|Llongfile) != 0 {
-		// Release lock while getting caller info - it's expensive.
-		l.mu.Unlock()
-		var ok bool
-		_, file, line, ok = runtime.Caller(calldepth)
-		if !ok {
-			file = "???"
-			line = 0
-		}
-		l.mu.Lock()
-	}
-	l.buf = l.buf[:0]
-	l.formatHeader(&l.buf, now, file, line)
-	l.buf = append(l.buf, s...)
-	if len(s) == 0 || s[len(s)-1] != '\n' {
-		l.buf = append(l.buf, '\n')
-	}
-	_, err := l.out.Write(l.buf)
-	return err
-}
-
-// Printf calls l.Output to print to the logger.
-// Arguments are handled in the manner of fmt.Printf.
-func (l *Logger) Printf(format string, v ...any) {
-	if atomic.LoadInt32(&l.isDiscard) != 0 {
-		return
-	}
-	l.Output(2, fmt.Sprintf(format, v...))
-}
-
-// Print calls l.Output to print to the logger.
-// Arguments are handled in the manner of fmt.Print.
-func (l *Logger) Print(v ...any) {
-	if atomic.LoadInt32(&l.isDiscard) != 0 {
-		return
-	}
-	l.Output(2, fmt.Sprint(v...))
-}
-
-// Println calls l.Output to print to the logger.
-// Arguments are handled in the manner of fmt.Println.
-func (l *Logger) Println(v ...any) {
-	if atomic.LoadInt32(&l.isDiscard) != 0 {
-		return
-	}
-	l.Output(2, fmt.Sprintln(v...))
-}
-
-// Fatal is equivalent to l.Print() followed by a call to os.Exit(1).
-func (l *Logger) Fatal(v ...any) {
-	l.Output(2, fmt.Sprint(v...))
-	os.Exit(1)
-}
-
-// Fatalf is equivalent to l.Printf() followed by a call to os.Exit(1).
-func (l *Logger) Fatalf(format string, v ...any) {
-	l.Output(2, fmt.Sprintf(format, v...))
-	os.Exit(1)
-}
-
-// Fatalln is equivalent to l.Println() followed by a call to os.Exit(1).
-func (l *Logger) Fatalln(v ...any) {
-	l.Output(2, fmt.Sprintln(v...))
-	os.Exit(1)
-}
-
-// Panic is equivalent to l.Print() followed by a call to panic().
-func (l *Logger) Panic(v ...any) {
-	s := fmt.Sprint(v...)
-	l.Output(2, s)
-	panic(s)
-}
-
-// Panicf is equivalent to l.Printf() followed by a call to panic().
-func (l *Logger) Panicf(format string, v ...any) {
-	s := fmt.Sprintf(format, v...)
-	l.Output(2, s)
-	panic(s)
-}
-
-// Panicln is equivalent to l.Println() followed by a call to panic().
-func (l *Logger) Panicln(v ...any) {
-	s := fmt.Sprintln(v...)
-	l.Output(2, s)
-	panic(s)
-}
-
-// Flags returns the output flags for the logger.
-// The flag bits are Ldate, Ltime, and so on.
-func (l *Logger) Flags() int {
-	l.mu.Lock()
-	defer l.mu.Unlock()
-	return l.flag
-}
-
-// SetFlags sets the output flags for the logger.
-// The flag bits are Ldate, Ltime, and so on.
-func (l *Logger) SetFlags(flag int) {
-	l.mu.Lock()
-	defer l.mu.Unlock()
-	l.flag = flag
-}
-
-// Prefix returns the output prefix for the logger.
-func (l *Logger) Prefix() string {
-	l.mu.Lock()
-	defer l.mu.Unlock()
-	return l.prefix
-}
-
-// SetPrefix sets the output prefix for the logger.
-func (l *Logger) SetPrefix(prefix string) {
-	l.mu.Lock()
-	defer l.mu.Unlock()
-	l.prefix = prefix
-}
-
-// Writer returns the output destination for the logger.
-func (l *Logger) Writer() io.Writer {
-	l.mu.Lock()
-	defer l.mu.Unlock()
-	return l.out
-}
-
-// SetOutput sets the output destination for the standard logger.
-func SetOutput(w io.Writer) {
-	std.SetOutput(w)
-}
-
-// Flags returns the output flags for the standard logger.
-// The flag bits are Ldate, Ltime, and so on.
-func Flags() int {
-	return std.Flags()
-}
-
-// SetFlags sets the output flags for the standard logger.
-// The flag bits are Ldate, Ltime, and so on.
-func SetFlags(flag int) {
-	std.SetFlags(flag)
-}
-
-// Prefix returns the output prefix for the standard logger.
-func Prefix() string {
-	return std.Prefix()
-}
-
-// SetPrefix sets the output prefix for the standard logger.
-func SetPrefix(prefix string) {
-	std.SetPrefix(prefix)
-}
-
-// Writer returns the output destination for the standard logger.
-func Writer() io.Writer {
-	return std.Writer()
-}
-
-// These functions write to the standard logger.
-
-// Print calls Output to print to the standard logger.
-// Arguments are handled in the manner of fmt.Print.
-func Print(v ...any) {
-	if atomic.LoadInt32(&std.isDiscard) != 0 {
-		return
-	}
-	std.Output(2, fmt.Sprint(v...))
-}
-
-// Printf calls Output to print to the standard logger.
-// Arguments are handled in the manner of fmt.Printf.
-func Printf(format string, v ...any) {
-	if atomic.LoadInt32(&std.isDiscard) != 0 {
-		return
-	}
-	std.Output(2, fmt.Sprintf(format, v...))
-}
-
-// Println calls Output to print to the standard logger.
-// Arguments are handled in the manner of fmt.Println.
-func Println(v ...any) {
-	if atomic.LoadInt32(&std.isDiscard) != 0 {
-		return
-	}
-	std.Output(2, fmt.Sprintln(v...))
-}
-
-// Fatal is equivalent to Print() followed by a call to os.Exit(1).
-func Fatal(v ...any) {
-	std.Output(2, fmt.Sprint(v...))
-	os.Exit(1)
-}
-
-// Fatalf is equivalent to Printf() followed by a call to os.Exit(1).
-func Fatalf(format string, v ...any) {
-	std.Output(2, fmt.Sprintf(format, v...))
-	os.Exit(1)
-}
-
-// Fatalln is equivalent to Println() followed by a call to os.Exit(1).
-func Fatalln(v ...any) {
-	std.Output(2, fmt.Sprintln(v...))
-	os.Exit(1)
-}
-
-// Panic is equivalent to Print() followed by a call to panic().
-func Panic(v ...any) {
-	s := fmt.Sprint(v...)
-	std.Output(2, s)
-	panic(s)
-}
-
-// Panicf is equivalent to Printf() followed by a call to panic().
-func Panicf(format string, v ...any) {
-	s := fmt.Sprintf(format, v...)
-	std.Output(2, s)
-	panic(s)
-}
-
-// Panicln is equivalent to Println() followed by a call to panic().
-func Panicln(v ...any) {
-	s := fmt.Sprintln(v...)
-	std.Output(2, s)
-	panic(s)
-}
-
-// Output writes the output for a logging event. The string s contains
-// the text to print after the prefix specified by the flags of the
-// Logger. A newline is appended if the last character of s is not
-// already a newline. Calldepth is the count of the number of
-// frames to skip when computing the file name and line number
-// if Llongfile or Lshortfile is set; a value of 1 will print the details
-// for the caller of Output.
-func Output(calldepth int, s string) error {
-	return std.Output(calldepth+1, s) // +1 for this frame.
-}
diff --git a/contrib/go/_std_1.18/src/math/abs.go b/contrib/go/_std_1.18/src/math/abs.go
deleted file mode 100644
index df83add695..0000000000
--- a/contrib/go/_std_1.18/src/math/abs.go
+++ /dev/null
@@ -1,14 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-// Abs returns the absolute value of x.
-//
-// Special cases are:
-//	Abs(±Inf) = +Inf
-//	Abs(NaN) = NaN
-func Abs(x float64) float64 {
-	return Float64frombits(Float64bits(x) &^ (1 << 63))
-}
diff --git a/contrib/go/_std_1.18/src/math/acosh.go b/contrib/go/_std_1.18/src/math/acosh.go
deleted file mode 100644
index f74e0b62fb..0000000000
--- a/contrib/go/_std_1.18/src/math/acosh.go
+++ /dev/null
@@ -1,64 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-// The original C code, the long comment, and the constants
-// below are from FreeBSD's /usr/src/lib/msun/src/e_acosh.c
-// and came with this notice. The go code is a simplified
-// version of the original C.
-//
-// ====================================================
-// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
-//
-// Developed at SunPro, a Sun Microsystems, Inc. business.
-// Permission to use, copy, modify, and distribute this
-// software is freely granted, provided that this notice
-// is preserved.
-// ====================================================
-//
-//
-// __ieee754_acosh(x)
-// Method :
-//	Based on
-//	        acosh(x) = log [ x + sqrt(x*x-1) ]
-//	we have
-//	        acosh(x) := log(x)+ln2,	if x is large; else
-//	        acosh(x) := log(2x-1/(sqrt(x*x-1)+x)) if x>2; else
-//	        acosh(x) := log1p(t+sqrt(2.0*t+t*t)); where t=x-1.
-//
-// Special cases:
-//	acosh(x) is NaN with signal if x<1.
-//	acosh(NaN) is NaN without signal.
-//
-
-// Acosh returns the inverse hyperbolic cosine of x.
-//
-// Special cases are:
-//	Acosh(+Inf) = +Inf
-//	Acosh(x) = NaN if x < 1
-//	Acosh(NaN) = NaN
-func Acosh(x float64) float64 {
-	if haveArchAcosh {
-		return archAcosh(x)
-	}
-	return acosh(x)
-}
-
-func acosh(x float64) float64 {
-	const Large = 1 << 28 // 2**28
-	// first case is special case
-	switch {
-	case x < 1 || IsNaN(x):
-		return NaN()
-	case x == 1:
-		return 0
-	case x >= Large:
-		return Log(x) + Ln2 // x > 2**28
-	case x > 2:
-		return Log(2*x - 1/(x+Sqrt(x*x-1))) // 2**28 > x > 2
-	}
-	t := x - 1
-	return Log1p(t + Sqrt(2*t+t*t)) // 2 >= x > 1
-}
diff --git a/contrib/go/_std_1.18/src/math/asin.go b/contrib/go/_std_1.18/src/math/asin.go
deleted file mode 100644
index 989a74155b..0000000000
--- a/contrib/go/_std_1.18/src/math/asin.go
+++ /dev/null
@@ -1,65 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-/*
-	Floating-point arcsine and arccosine.
-
-	They are implemented by computing the arctangent
-	after appropriate range reduction.
-*/
-
-// Asin returns the arcsine, in radians, of x.
-//
-// Special cases are:
-//	Asin(±0) = ±0
-//	Asin(x) = NaN if x < -1 or x > 1
-func Asin(x float64) float64 {
-	if haveArchAsin {
-		return archAsin(x)
-	}
-	return asin(x)
-}
-
-func asin(x float64) float64 {
-	if x == 0 {
-		return x // special case
-	}
-	sign := false
-	if x < 0 {
-		x = -x
-		sign = true
-	}
-	if x > 1 {
-		return NaN() // special case
-	}
-
-	temp := Sqrt(1 - x*x)
-	if x > 0.7 {
-		temp = Pi/2 - satan(temp/x)
-	} else {
-		temp = satan(x / temp)
-	}
-
-	if sign {
-		temp = -temp
-	}
-	return temp
-}
-
-// Acos returns the arccosine, in radians, of x.
-//
-// Special case is:
-//	Acos(x) = NaN if x < -1 or x > 1
-func Acos(x float64) float64 {
-	if haveArchAcos {
-		return archAcos(x)
-	}
-	return acos(x)
-}
-
-func acos(x float64) float64 {
-	return Pi/2 - Asin(x)
-}
diff --git a/contrib/go/_std_1.18/src/math/asinh.go b/contrib/go/_std_1.18/src/math/asinh.go
deleted file mode 100644
index 6dcb241c1f..0000000000
--- a/contrib/go/_std_1.18/src/math/asinh.go
+++ /dev/null
@@ -1,76 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-// The original C code, the long comment, and the constants
-// below are from FreeBSD's /usr/src/lib/msun/src/s_asinh.c
-// and came with this notice. The go code is a simplified
-// version of the original C.
-//
-// ====================================================
-// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
-//
-// Developed at SunPro, a Sun Microsystems, Inc. business.
-// Permission to use, copy, modify, and distribute this
-// software is freely granted, provided that this notice
-// is preserved.
-// ====================================================
-//
-//
-// asinh(x)
-// Method :
-//	Based on
-//	        asinh(x) = sign(x) * log [ |x| + sqrt(x*x+1) ]
-//	we have
-//	asinh(x) := x  if  1+x*x=1,
-//	         := sign(x)*(log(x)+ln2)) for large |x|, else
-//	         := sign(x)*log(2|x|+1/(|x|+sqrt(x*x+1))) if|x|>2, else
-//	         := sign(x)*log1p(|x| + x**2/(1 + sqrt(1+x**2)))
-//
-
-// Asinh returns the inverse hyperbolic sine of x.
-//
-// Special cases are:
-//	Asinh(±0) = ±0
-//	Asinh(±Inf) = ±Inf
-//	Asinh(NaN) = NaN
-func Asinh(x float64) float64 {
-	if haveArchAsinh {
-		return archAsinh(x)
-	}
-	return asinh(x)
-}
-
-func asinh(x float64) float64 {
-	const (
-		Ln2      = 6.93147180559945286227e-01 // 0x3FE62E42FEFA39EF
-		NearZero = 1.0 / (1 << 28)            // 2**-28
-		Large    = 1 << 28                    // 2**28
-	)
-	// special cases
-	if IsNaN(x) || IsInf(x, 0) {
-		return x
-	}
-	sign := false
-	if x < 0 {
-		x = -x
-		sign = true
-	}
-	var temp float64
-	switch {
-	case x > Large:
-		temp = Log(x) + Ln2 // |x| > 2**28
-	case x > 2:
-		temp = Log(2*x + 1/(Sqrt(x*x+1)+x)) // 2**28 > |x| > 2.0
-	case x < NearZero:
-		temp = x // |x| < 2**-28
-	default:
-		temp = Log1p(x + x*x/(1+Sqrt(1+x*x))) // 2.0 > |x| > 2**-28
-	}
-	if sign {
-		temp = -temp
-	}
-	return temp
-}
diff --git a/contrib/go/_std_1.18/src/math/atan.go b/contrib/go/_std_1.18/src/math/atan.go
deleted file mode 100644
index 69af860161..0000000000
--- a/contrib/go/_std_1.18/src/math/atan.go
+++ /dev/null
@@ -1,110 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-/*
-	Floating-point arctangent.
-*/
-
-// The original C code, the long comment, and the constants below were
-// from http://netlib.sandia.gov/cephes/cmath/atan.c, available from
-// http://www.netlib.org/cephes/cmath.tgz.
-// The go code is a version of the original C.
-//
-// atan.c
-// Inverse circular tangent (arctangent)
-//
-// SYNOPSIS:
-// double x, y, atan();
-// y = atan( x );
-//
-// DESCRIPTION:
-// Returns radian angle between -pi/2 and +pi/2 whose tangent is x.
-//
-// Range reduction is from three intervals into the interval from zero to 0.66.
-// The approximant uses a rational function of degree 4/5 of the form
-// x + x**3 P(x)/Q(x).
-//
-// ACCURACY:
-//                      Relative error:
-// arithmetic   domain    # trials  peak     rms
-//    DEC       -10, 10   50000     2.4e-17  8.3e-18
-//    IEEE      -10, 10   10^6      1.8e-16  5.0e-17
-//
-// Cephes Math Library Release 2.8:  June, 2000
-// Copyright 1984, 1987, 1989, 1992, 2000 by Stephen L. Moshier
-//
-// The readme file at http://netlib.sandia.gov/cephes/ says:
-//    Some software in this archive may be from the book _Methods and
-// Programs for Mathematical Functions_ (Prentice-Hall or Simon & Schuster
-// International, 1989) or from the Cephes Mathematical Library, a
-// commercial product. In either event, it is copyrighted by the author.
-// What you see here may be used freely but it comes with no support or
-// guarantee.
-//
-//   The two known misprints in the book are repaired here in the
-// source listings for the gamma function and the incomplete beta
-// integral.
-//
-//   Stephen L. Moshier
-//   moshier@na-net.ornl.gov
-
-// xatan evaluates a series valid in the range [0, 0.66].
-func xatan(x float64) float64 {
-	const (
-		P0 = -8.750608600031904122785e-01
-		P1 = -1.615753718733365076637e+01
-		P2 = -7.500855792314704667340e+01
-		P3 = -1.228866684490136173410e+02
-		P4 = -6.485021904942025371773e+01
-		Q0 = +2.485846490142306297962e+01
-		Q1 = +1.650270098316988542046e+02
-		Q2 = +4.328810604912902668951e+02
-		Q3 = +4.853903996359136964868e+02
-		Q4 = +1.945506571482613964425e+02
-	)
-	z := x * x
-	z = z * ((((P0*z+P1)*z+P2)*z+P3)*z + P4) / (((((z+Q0)*z+Q1)*z+Q2)*z+Q3)*z + Q4)
-	z = x*z + x
-	return z
-}
-
-// satan reduces its argument (known to be positive)
-// to the range [0, 0.66] and calls xatan.
-func satan(x float64) float64 {
-	const (
-		Morebits = 6.123233995736765886130e-17 // pi/2 = PIO2 + Morebits
-		Tan3pio8 = 2.41421356237309504880      // tan(3*pi/8)
-	)
-	if x <= 0.66 {
-		return xatan(x)
-	}
-	if x > Tan3pio8 {
-		return Pi/2 - xatan(1/x) + Morebits
-	}
-	return Pi/4 + xatan((x-1)/(x+1)) + 0.5*Morebits
-}
-
-// Atan returns the arctangent, in radians, of x.
-//
-// Special cases are:
-//      Atan(±0) = ±0
-//      Atan(±Inf) = ±Pi/2
-func Atan(x float64) float64 {
-	if haveArchAtan {
-		return archAtan(x)
-	}
-	return atan(x)
-}
-
-func atan(x float64) float64 {
-	if x == 0 {
-		return x
-	}
-	if x > 0 {
-		return satan(x)
-	}
-	return -satan(-x)
-}
diff --git a/contrib/go/_std_1.18/src/math/atan2.go b/contrib/go/_std_1.18/src/math/atan2.go
deleted file mode 100644
index 11d7e81acd..0000000000
--- a/contrib/go/_std_1.18/src/math/atan2.go
+++ /dev/null
@@ -1,76 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-// Atan2 returns the arc tangent of y/x, using
-// the signs of the two to determine the quadrant
-// of the return value.
-//
-// Special cases are (in order):
-//	Atan2(y, NaN) = NaN
-//	Atan2(NaN, x) = NaN
-//	Atan2(+0, x>=0) = +0
-//	Atan2(-0, x>=0) = -0
-//	Atan2(+0, x<=-0) = +Pi
-//	Atan2(-0, x<=-0) = -Pi
-//	Atan2(y>0, 0) = +Pi/2
-//	Atan2(y<0, 0) = -Pi/2
-//	Atan2(+Inf, +Inf) = +Pi/4
-//	Atan2(-Inf, +Inf) = -Pi/4
-//	Atan2(+Inf, -Inf) = 3Pi/4
-//	Atan2(-Inf, -Inf) = -3Pi/4
-//	Atan2(y, +Inf) = 0
-//	Atan2(y>0, -Inf) = +Pi
-//	Atan2(y<0, -Inf) = -Pi
-//	Atan2(+Inf, x) = +Pi/2
-//	Atan2(-Inf, x) = -Pi/2
-func Atan2(y, x float64) float64 {
-	if haveArchAtan2 {
-		return archAtan2(y, x)
-	}
-	return atan2(y, x)
-}
-
-func atan2(y, x float64) float64 {
-	// special cases
-	switch {
-	case IsNaN(y) || IsNaN(x):
-		return NaN()
-	case y == 0:
-		if x >= 0 && !Signbit(x) {
-			return Copysign(0, y)
-		}
-		return Copysign(Pi, y)
-	case x == 0:
-		return Copysign(Pi/2, y)
-	case IsInf(x, 0):
-		if IsInf(x, 1) {
-			switch {
-			case IsInf(y, 0):
-				return Copysign(Pi/4, y)
-			default:
-				return Copysign(0, y)
-			}
-		}
-		switch {
-		case IsInf(y, 0):
-			return Copysign(3*Pi/4, y)
-		default:
-			return Copysign(Pi, y)
-		}
-	case IsInf(y, 0):
-		return Copysign(Pi/2, y)
-	}
-
-	// Call atan and determine the quadrant.
-	q := Atan(y / x)
-	if x < 0 {
-		if q <= 0 {
-			return q + Pi
-		}
-		return q - Pi
-	}
-	return q
-}
diff --git a/contrib/go/_std_1.18/src/math/atanh.go b/contrib/go/_std_1.18/src/math/atanh.go
deleted file mode 100644
index fe8bd6d8a4..0000000000
--- a/contrib/go/_std_1.18/src/math/atanh.go
+++ /dev/null
@@ -1,84 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-// The original C code, the long comment, and the constants
-// below are from FreeBSD's /usr/src/lib/msun/src/e_atanh.c
-// and came with this notice. The go code is a simplified
-// version of the original C.
-//
-// ====================================================
-// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
-//
-// Developed at SunPro, a Sun Microsystems, Inc. business.
-// Permission to use, copy, modify, and distribute this
-// software is freely granted, provided that this notice
-// is preserved.
-// ====================================================
-//
-//
-// __ieee754_atanh(x)
-// Method :
-//	1. Reduce x to positive by atanh(-x) = -atanh(x)
-//	2. For x>=0.5
-//	            1              2x                          x
-//	atanh(x) = --- * log(1 + -------) = 0.5 * log1p(2 * --------)
-//	            2             1 - x                      1 - x
-//
-//	For x<0.5
-//	atanh(x) = 0.5*log1p(2x+2x*x/(1-x))
-//
-// Special cases:
-//	atanh(x) is NaN if |x| > 1 with signal;
-//	atanh(NaN) is that NaN with no signal;
-//	atanh(+-1) is +-INF with signal.
-//
-
-// Atanh returns the inverse hyperbolic tangent of x.
-//
-// Special cases are:
-//	Atanh(1) = +Inf
-//	Atanh(±0) = ±0
-//	Atanh(-1) = -Inf
-//	Atanh(x) = NaN if x < -1 or x > 1
-//	Atanh(NaN) = NaN
-func Atanh(x float64) float64 {
-	if haveArchAtanh {
-		return archAtanh(x)
-	}
-	return atanh(x)
-}
-
-func atanh(x float64) float64 {
-	const NearZero = 1.0 / (1 << 28) // 2**-28
-	// special cases
-	switch {
-	case x < -1 || x > 1 || IsNaN(x):
-		return NaN()
-	case x == 1:
-		return Inf(1)
-	case x == -1:
-		return Inf(-1)
-	}
-	sign := false
-	if x < 0 {
-		x = -x
-		sign = true
-	}
-	var temp float64
-	switch {
-	case x < NearZero:
-		temp = x
-	case x < 0.5:
-		temp = x + x
-		temp = 0.5 * Log1p(temp+temp*x/(1-x))
-	default:
-		temp = 0.5 * Log1p((x+x)/(1-x))
-	}
-	if sign {
-		temp = -temp
-	}
-	return temp
-}
diff --git a/contrib/go/_std_1.18/src/math/big/arith.go b/contrib/go/_std_1.18/src/math/big/arith.go
deleted file mode 100644
index 8f55c195d4..0000000000
--- a/contrib/go/_std_1.18/src/math/big/arith.go
+++ /dev/null
@@ -1,277 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file provides Go implementations of elementary multi-precision
-// arithmetic operations on word vectors. These have the suffix _g.
-// These are needed for platforms without assembly implementations of these routines.
-// This file also contains elementary operations that can be implemented
-// sufficiently efficiently in Go.
-
-package big
-
-import "math/bits"
-
-// A Word represents a single digit of a multi-precision unsigned integer.
-type Word uint
-
-const (
-	_S = _W / 8 // word size in bytes
-
-	_W = bits.UintSize // word size in bits
-	_B = 1 << _W       // digit base
-	_M = _B - 1        // digit mask
-)
-
-// Many of the loops in this file are of the form
-//   for i := 0; i < len(z) && i < len(x) && i < len(y); i++
-// i < len(z) is the real condition.
-// However, checking i < len(x) && i < len(y) as well is faster than
-// having the compiler do a bounds check in the body of the loop;
-// remarkably it is even faster than hoisting the bounds check
-// out of the loop, by doing something like
-//   _, _ = x[len(z)-1], y[len(z)-1]
-// There are other ways to hoist the bounds check out of the loop,
-// but the compiler's BCE isn't powerful enough for them (yet?).
-// See the discussion in CL 164966.
-
-// ----------------------------------------------------------------------------
-// Elementary operations on words
-//
-// These operations are used by the vector operations below.
-
-// z1<<_W + z0 = x*y
-func mulWW_g(x, y Word) (z1, z0 Word) {
-	hi, lo := bits.Mul(uint(x), uint(y))
-	return Word(hi), Word(lo)
-}
-
-// z1<<_W + z0 = x*y + c
-func mulAddWWW_g(x, y, c Word) (z1, z0 Word) {
-	hi, lo := bits.Mul(uint(x), uint(y))
-	var cc uint
-	lo, cc = bits.Add(lo, uint(c), 0)
-	return Word(hi + cc), Word(lo)
-}
-
-// nlz returns the number of leading zeros in x.
-// Wraps bits.LeadingZeros call for convenience.
-func nlz(x Word) uint {
-	return uint(bits.LeadingZeros(uint(x)))
-}
-
-// The resulting carry c is either 0 or 1.
-func addVV_g(z, x, y []Word) (c Word) {
-	// The comment near the top of this file discusses this for loop condition.
-	for i := 0; i < len(z) && i < len(x) && i < len(y); i++ {
-		zi, cc := bits.Add(uint(x[i]), uint(y[i]), uint(c))
-		z[i] = Word(zi)
-		c = Word(cc)
-	}
-	return
-}
-
-// The resulting carry c is either 0 or 1.
-func subVV_g(z, x, y []Word) (c Word) {
-	// The comment near the top of this file discusses this for loop condition.
-	for i := 0; i < len(z) && i < len(x) && i < len(y); i++ {
-		zi, cc := bits.Sub(uint(x[i]), uint(y[i]), uint(c))
-		z[i] = Word(zi)
-		c = Word(cc)
-	}
-	return
-}
-
-// The resulting carry c is either 0 or 1.
-func addVW_g(z, x []Word, y Word) (c Word) {
-	c = y
-	// The comment near the top of this file discusses this for loop condition.
-	for i := 0; i < len(z) && i < len(x); i++ {
-		zi, cc := bits.Add(uint(x[i]), uint(c), 0)
-		z[i] = Word(zi)
-		c = Word(cc)
-	}
-	return
-}
-
-// addVWlarge is addVW, but intended for large z.
-// The only difference is that we check on every iteration
-// whether we are done with carries,
-// and if so, switch to a much faster copy instead.
-// This is only a good idea for large z,
-// because the overhead of the check and the function call
-// outweigh the benefits when z is small.
-func addVWlarge(z, x []Word, y Word) (c Word) {
-	c = y
-	// The comment near the top of this file discusses this for loop condition.
-	for i := 0; i < len(z) && i < len(x); i++ {
-		if c == 0 {
-			copy(z[i:], x[i:])
-			return
-		}
-		zi, cc := bits.Add(uint(x[i]), uint(c), 0)
-		z[i] = Word(zi)
-		c = Word(cc)
-	}
-	return
-}
-
-func subVW_g(z, x []Word, y Word) (c Word) {
-	c = y
-	// The comment near the top of this file discusses this for loop condition.
-	for i := 0; i < len(z) && i < len(x); i++ {
-		zi, cc := bits.Sub(uint(x[i]), uint(c), 0)
-		z[i] = Word(zi)
-		c = Word(cc)
-	}
-	return
-}
-
-// subVWlarge is to subVW as addVWlarge is to addVW.
-func subVWlarge(z, x []Word, y Word) (c Word) {
-	c = y
-	// The comment near the top of this file discusses this for loop condition.
-	for i := 0; i < len(z) && i < len(x); i++ {
-		if c == 0 {
-			copy(z[i:], x[i:])
-			return
-		}
-		zi, cc := bits.Sub(uint(x[i]), uint(c), 0)
-		z[i] = Word(zi)
-		c = Word(cc)
-	}
-	return
-}
-
-func shlVU_g(z, x []Word, s uint) (c Word) {
-	if s == 0 {
-		copy(z, x)
-		return
-	}
-	if len(z) == 0 {
-		return
-	}
-	s &= _W - 1 // hint to the compiler that shifts by s don't need guard code
-	ŝ := _W - s
-	ŝ &= _W - 1 // ditto
-	c = x[len(z)-1] >> ŝ
-	for i := len(z) - 1; i > 0; i-- {
-		z[i] = x[i]<<s | x[i-1]>>ŝ
-	}
-	z[0] = x[0] << s
-	return
-}
-
-func shrVU_g(z, x []Word, s uint) (c Word) {
-	if s == 0 {
-		copy(z, x)
-		return
-	}
-	if len(z) == 0 {
-		return
-	}
-	if len(x) != len(z) {
-		// This is an invariant guaranteed by the caller.
-		panic("len(x) != len(z)")
-	}
-	s &= _W - 1 // hint to the compiler that shifts by s don't need guard code
-	ŝ := _W - s
-	ŝ &= _W - 1 // ditto
-	c = x[0] << ŝ
-	for i := 1; i < len(z); i++ {
-		z[i-1] = x[i-1]>>s | x[i]<<ŝ
-	}
-	z[len(z)-1] = x[len(z)-1] >> s
-	return
-}
-
-func mulAddVWW_g(z, x []Word, y, r Word) (c Word) {
-	c = r
-	// The comment near the top of this file discusses this for loop condition.
-	for i := 0; i < len(z) && i < len(x); i++ {
-		c, z[i] = mulAddWWW_g(x[i], y, c)
-	}
-	return
-}
-
-func addMulVVW_g(z, x []Word, y Word) (c Word) {
-	// The comment near the top of this file discusses this for loop condition.
-	for i := 0; i < len(z) && i < len(x); i++ {
-		z1, z0 := mulAddWWW_g(x[i], y, z[i])
-		lo, cc := bits.Add(uint(z0), uint(c), 0)
-		c, z[i] = Word(cc), Word(lo)
-		c += z1
-	}
-	return
-}
-
-// q = ( x1 << _W + x0 - r)/y. m = floor(( _B^2 - 1 ) / d - _B). Requiring x1<y.
-// An approximate reciprocal with a reference to "Improved Division by Invariant Integers
-// (IEEE Transactions on Computers, 11 Jun. 2010)"
-func divWW(x1, x0, y, m Word) (q, r Word) {
-	s := nlz(y)
-	if s != 0 {
-		x1 = x1<<s | x0>>(_W-s)
-		x0 <<= s
-		y <<= s
-	}
-	d := uint(y)
-	// We know that
-	//   m = ⎣(B^2-1)/d⎦-B
-	//   ⎣(B^2-1)/d⎦ = m+B
-	//   (B^2-1)/d = m+B+delta1    0 <= delta1 <= (d-1)/d
-	//   B^2/d = m+B+delta2        0 <= delta2 <= 1
-	// The quotient we're trying to compute is
-	//   quotient = ⎣(x1*B+x0)/d⎦
-	//            = ⎣(x1*B*(B^2/d)+x0*(B^2/d))/B^2⎦
-	//            = ⎣(x1*B*(m+B+delta2)+x0*(m+B+delta2))/B^2⎦
-	//            = ⎣(x1*m+x1*B+x0)/B + x0*m/B^2 + delta2*(x1*B+x0)/B^2⎦
-	// The latter two terms of this three-term sum are between 0 and 1.
-	// So we can compute just the first term, and we will be low by at most 2.
-	t1, t0 := bits.Mul(uint(m), uint(x1))
-	_, c := bits.Add(t0, uint(x0), 0)
-	t1, _ = bits.Add(t1, uint(x1), c)
-	// The quotient is either t1, t1+1, or t1+2.
-	// We'll try t1 and adjust if needed.
-	qq := t1
-	// compute remainder r=x-d*q.
-	dq1, dq0 := bits.Mul(d, qq)
-	r0, b := bits.Sub(uint(x0), dq0, 0)
-	r1, _ := bits.Sub(uint(x1), dq1, b)
-	// The remainder we just computed is bounded above by B+d:
-	// r = x1*B + x0 - d*q.
-	//   = x1*B + x0 - d*⎣(x1*m+x1*B+x0)/B⎦
-	//   = x1*B + x0 - d*((x1*m+x1*B+x0)/B-alpha)                                   0 <= alpha < 1
-	//   = x1*B + x0 - x1*d/B*m                         - x1*d - x0*d/B + d*alpha
-	//   = x1*B + x0 - x1*d/B*⎣(B^2-1)/d-B⎦             - x1*d - x0*d/B + d*alpha
-	//   = x1*B + x0 - x1*d/B*⎣(B^2-1)/d-B⎦             - x1*d - x0*d/B + d*alpha
-	//   = x1*B + x0 - x1*d/B*((B^2-1)/d-B-beta)        - x1*d - x0*d/B + d*alpha   0 <= beta < 1
-	//   = x1*B + x0 - x1*B + x1/B + x1*d + x1*d/B*beta - x1*d - x0*d/B + d*alpha
-	//   =        x0        + x1/B        + x1*d/B*beta        - x0*d/B + d*alpha
-	//   = x0*(1-d/B) + x1*(1+d*beta)/B + d*alpha
-	//   <  B*(1-d/B) +  d*B/B          + d          because x0<B (and 1-d/B>0), x1<d, 1+d*beta<=B, alpha<1
-	//   =  B - d     +  d              + d
-	//   = B+d
-	// So r1 can only be 0 or 1. If r1 is 1, then we know q was too small.
-	// Add 1 to q and subtract d from r. That guarantees that r is <B, so
-	// we no longer need to keep track of r1.
-	if r1 != 0 {
-		qq++
-		r0 -= d
-	}
-	// If the remainder is still too large, increment q one more time.
-	if r0 >= d {
-		qq++
-		r0 -= d
-	}
-	return Word(qq), Word(r0 >> s)
-}
-
-// reciprocalWord return the reciprocal of the divisor. rec = floor(( _B^2 - 1 ) / u - _B). u = d1 << nlz(d1).
-func reciprocalWord(d1 Word) Word {
-	u := uint(d1 << nlz(d1))
-	x1 := ^u
-	x0 := uint(_M)
-	rec, _ := bits.Div(x1, x0, u) // (_B^2-1)/U-_B = (_B*(_M-C)+_M)/U
-	return Word(rec)
-}
diff --git a/contrib/go/_std_1.18/src/math/big/arith_amd64.s b/contrib/go/_std_1.18/src/math/big/arith_amd64.s
deleted file mode 100644
index 5c72a27d8d..0000000000
--- a/contrib/go/_std_1.18/src/math/big/arith_amd64.s
+++ /dev/null
@@ -1,526 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build !math_big_pure_go
-// +build !math_big_pure_go
-
-#include "textflag.h"
-
-// This file provides fast assembly versions for the elementary
-// arithmetic operations on vectors implemented in arith.go.
-
-// func mulWW(x, y Word) (z1, z0 Word)
-TEXT ·mulWW(SB),NOSPLIT,$0
-	MOVQ x+0(FP), AX
-	MULQ y+8(FP)
-	MOVQ DX, z1+16(FP)
-	MOVQ AX, z0+24(FP)
-	RET
-
-
-
-// The carry bit is saved with SBBQ Rx, Rx: if the carry was set, Rx is -1, otherwise it is 0.
-// It is restored with ADDQ Rx, Rx: if Rx was -1 the carry is set, otherwise it is cleared.
-// This is faster than using rotate instructions.
-
-// func addVV(z, x, y []Word) (c Word)
-TEXT ·addVV(SB),NOSPLIT,$0
-	MOVQ z_len+8(FP), DI
-	MOVQ x+24(FP), R8
-	MOVQ y+48(FP), R9
-	MOVQ z+0(FP), R10
-
-	MOVQ $0, CX		// c = 0
-	MOVQ $0, SI		// i = 0
-
-	// s/JL/JMP/ below to disable the unrolled loop
-	SUBQ $4, DI		// n -= 4
-	JL V1			// if n < 0 goto V1
-
-U1:	// n >= 0
-	// regular loop body unrolled 4x
-	ADDQ CX, CX		// restore CF
-	MOVQ 0(R8)(SI*8), R11
-	MOVQ 8(R8)(SI*8), R12
-	MOVQ 16(R8)(SI*8), R13
-	MOVQ 24(R8)(SI*8), R14
-	ADCQ 0(R9)(SI*8), R11
-	ADCQ 8(R9)(SI*8), R12
-	ADCQ 16(R9)(SI*8), R13
-	ADCQ 24(R9)(SI*8), R14
-	MOVQ R11, 0(R10)(SI*8)
-	MOVQ R12, 8(R10)(SI*8)
-	MOVQ R13, 16(R10)(SI*8)
-	MOVQ R14, 24(R10)(SI*8)
-	SBBQ CX, CX		// save CF
-
-	ADDQ $4, SI		// i += 4
-	SUBQ $4, DI		// n -= 4
-	JGE U1			// if n >= 0 goto U1
-
-V1:	ADDQ $4, DI		// n += 4
-	JLE E1			// if n <= 0 goto E1
-
-L1:	// n > 0
-	ADDQ CX, CX		// restore CF
-	MOVQ 0(R8)(SI*8), R11
-	ADCQ 0(R9)(SI*8), R11
-	MOVQ R11, 0(R10)(SI*8)
-	SBBQ CX, CX		// save CF
-
-	ADDQ $1, SI		// i++
-	SUBQ $1, DI		// n--
-	JG L1			// if n > 0 goto L1
-
-E1:	NEGQ CX
-	MOVQ CX, c+72(FP)	// return c
-	RET
-
-
-// func subVV(z, x, y []Word) (c Word)
-// (same as addVV except for SBBQ instead of ADCQ and label names)
-TEXT ·subVV(SB),NOSPLIT,$0
-	MOVQ z_len+8(FP), DI
-	MOVQ x+24(FP), R8
-	MOVQ y+48(FP), R9
-	MOVQ z+0(FP), R10
-
-	MOVQ $0, CX		// c = 0
-	MOVQ $0, SI		// i = 0
-
-	// s/JL/JMP/ below to disable the unrolled loop
-	SUBQ $4, DI		// n -= 4
-	JL V2			// if n < 0 goto V2
-
-U2:	// n >= 0
-	// regular loop body unrolled 4x
-	ADDQ CX, CX		// restore CF
-	MOVQ 0(R8)(SI*8), R11
-	MOVQ 8(R8)(SI*8), R12
-	MOVQ 16(R8)(SI*8), R13
-	MOVQ 24(R8)(SI*8), R14
-	SBBQ 0(R9)(SI*8), R11
-	SBBQ 8(R9)(SI*8), R12
-	SBBQ 16(R9)(SI*8), R13
-	SBBQ 24(R9)(SI*8), R14
-	MOVQ R11, 0(R10)(SI*8)
-	MOVQ R12, 8(R10)(SI*8)
-	MOVQ R13, 16(R10)(SI*8)
-	MOVQ R14, 24(R10)(SI*8)
-	SBBQ CX, CX		// save CF
-
-	ADDQ $4, SI		// i += 4
-	SUBQ $4, DI		// n -= 4
-	JGE U2			// if n >= 0 goto U2
-
-V2:	ADDQ $4, DI		// n += 4
-	JLE E2			// if n <= 0 goto E2
-
-L2:	// n > 0
-	ADDQ CX, CX		// restore CF
-	MOVQ 0(R8)(SI*8), R11
-	SBBQ 0(R9)(SI*8), R11
-	MOVQ R11, 0(R10)(SI*8)
-	SBBQ CX, CX		// save CF
-
-	ADDQ $1, SI		// i++
-	SUBQ $1, DI		// n--
-	JG L2			// if n > 0 goto L2
-
-E2:	NEGQ CX
-	MOVQ CX, c+72(FP)	// return c
-	RET
-
-
-// func addVW(z, x []Word, y Word) (c Word)
-TEXT ·addVW(SB),NOSPLIT,$0
-	MOVQ z_len+8(FP), DI
-	CMPQ DI, $32
-	JG large
-	MOVQ x+24(FP), R8
-	MOVQ y+48(FP), CX	// c = y
-	MOVQ z+0(FP), R10
-
-	MOVQ $0, SI		// i = 0
-
-	// s/JL/JMP/ below to disable the unrolled loop
-	SUBQ $4, DI		// n -= 4
-	JL V3			// if n < 4 goto V3
-
-U3:	// n >= 0
-	// regular loop body unrolled 4x
-	MOVQ 0(R8)(SI*8), R11
-	MOVQ 8(R8)(SI*8), R12
-	MOVQ 16(R8)(SI*8), R13
-	MOVQ 24(R8)(SI*8), R14
-	ADDQ CX, R11
-	ADCQ $0, R12
-	ADCQ $0, R13
-	ADCQ $0, R14
-	SBBQ CX, CX		// save CF
-	NEGQ CX
-	MOVQ R11, 0(R10)(SI*8)
-	MOVQ R12, 8(R10)(SI*8)
-	MOVQ R13, 16(R10)(SI*8)
-	MOVQ R14, 24(R10)(SI*8)
-
-	ADDQ $4, SI		// i += 4
-	SUBQ $4, DI		// n -= 4
-	JGE U3			// if n >= 0 goto U3
-
-V3:	ADDQ $4, DI		// n += 4
-	JLE E3			// if n <= 0 goto E3
-
-L3:	// n > 0
-	ADDQ 0(R8)(SI*8), CX
-	MOVQ CX, 0(R10)(SI*8)
-	SBBQ CX, CX		// save CF
-	NEGQ CX
-
-	ADDQ $1, SI		// i++
-	SUBQ $1, DI		// n--
-	JG L3			// if n > 0 goto L3
-
-E3:	MOVQ CX, c+56(FP)	// return c
-	RET
-large:
-	JMP ·addVWlarge(SB)
-
-
-// func subVW(z, x []Word, y Word) (c Word)
-// (same as addVW except for SUBQ/SBBQ instead of ADDQ/ADCQ and label names)
-TEXT ·subVW(SB),NOSPLIT,$0
-	MOVQ z_len+8(FP), DI
-	CMPQ DI, $32
-	JG large
-	MOVQ x+24(FP), R8
-	MOVQ y+48(FP), CX	// c = y
-	MOVQ z+0(FP), R10
-
-	MOVQ $0, SI		// i = 0
-
-	// s/JL/JMP/ below to disable the unrolled loop
-	SUBQ $4, DI		// n -= 4
-	JL V4			// if n < 4 goto V4
-
-U4:	// n >= 0
-	// regular loop body unrolled 4x
-	MOVQ 0(R8)(SI*8), R11
-	MOVQ 8(R8)(SI*8), R12
-	MOVQ 16(R8)(SI*8), R13
-	MOVQ 24(R8)(SI*8), R14
-	SUBQ CX, R11
-	SBBQ $0, R12
-	SBBQ $0, R13
-	SBBQ $0, R14
-	SBBQ CX, CX		// save CF
-	NEGQ CX
-	MOVQ R11, 0(R10)(SI*8)
-	MOVQ R12, 8(R10)(SI*8)
-	MOVQ R13, 16(R10)(SI*8)
-	MOVQ R14, 24(R10)(SI*8)
-
-	ADDQ $4, SI		// i += 4
-	SUBQ $4, DI		// n -= 4
-	JGE U4			// if n >= 0 goto U4
-
-V4:	ADDQ $4, DI		// n += 4
-	JLE E4			// if n <= 0 goto E4
-
-L4:	// n > 0
-	MOVQ 0(R8)(SI*8), R11
-	SUBQ CX, R11
-	MOVQ R11, 0(R10)(SI*8)
-	SBBQ CX, CX		// save CF
-	NEGQ CX
-
-	ADDQ $1, SI		// i++
-	SUBQ $1, DI		// n--
-	JG L4			// if n > 0 goto L4
-
-E4:	MOVQ CX, c+56(FP)	// return c
-	RET
-large:
-	JMP ·subVWlarge(SB)
-
-
-// func shlVU(z, x []Word, s uint) (c Word)
-TEXT ·shlVU(SB),NOSPLIT,$0
-	MOVQ z_len+8(FP), BX	// i = z
-	SUBQ $1, BX		// i--
-	JL X8b			// i < 0	(n <= 0)
-
-	// n > 0
-	MOVQ z+0(FP), R10
-	MOVQ x+24(FP), R8
-	MOVQ s+48(FP), CX
-	MOVQ (R8)(BX*8), AX	// w1 = x[n-1]
-	MOVQ $0, DX
-	SHLQ CX, AX, DX		// w1>>ŝ
-	MOVQ DX, c+56(FP)
-
-	CMPQ BX, $0
-	JLE X8a			// i <= 0
-
-	// i > 0
-L8:	MOVQ AX, DX		// w = w1
-	MOVQ -8(R8)(BX*8), AX	// w1 = x[i-1]
-	SHLQ CX, AX, DX		// w<<s | w1>>ŝ
-	MOVQ DX, (R10)(BX*8)	// z[i] = w<<s | w1>>ŝ
-	SUBQ $1, BX		// i--
-	JG L8			// i > 0
-
-	// i <= 0
-X8a:	SHLQ CX, AX		// w1<<s
-	MOVQ AX, (R10)		// z[0] = w1<<s
-	RET
-
-X8b:	MOVQ $0, c+56(FP)
-	RET
-
-
-// func shrVU(z, x []Word, s uint) (c Word)
-TEXT ·shrVU(SB),NOSPLIT,$0
-	MOVQ z_len+8(FP), R11
-	SUBQ $1, R11		// n--
-	JL X9b			// n < 0	(n <= 0)
-
-	// n > 0
-	MOVQ z+0(FP), R10
-	MOVQ x+24(FP), R8
-	MOVQ s+48(FP), CX
-	MOVQ (R8), AX		// w1 = x[0]
-	MOVQ $0, DX
-	SHRQ CX, AX, DX		// w1<<ŝ
-	MOVQ DX, c+56(FP)
-
-	MOVQ $0, BX		// i = 0
-	JMP E9
-
-	// i < n-1
-L9:	MOVQ AX, DX		// w = w1
-	MOVQ 8(R8)(BX*8), AX	// w1 = x[i+1]
-	SHRQ CX, AX, DX		// w>>s | w1<<ŝ
-	MOVQ DX, (R10)(BX*8)	// z[i] = w>>s | w1<<ŝ
-	ADDQ $1, BX		// i++
-
-E9:	CMPQ BX, R11
-	JL L9			// i < n-1
-
-	// i >= n-1
-X9a:	SHRQ CX, AX		// w1>>s
-	MOVQ AX, (R10)(R11*8)	// z[n-1] = w1>>s
-	RET
-
-X9b:	MOVQ $0, c+56(FP)
-	RET
-
-
-// func mulAddVWW(z, x []Word, y, r Word) (c Word)
-TEXT ·mulAddVWW(SB),NOSPLIT,$0
-	MOVQ z+0(FP), R10
-	MOVQ x+24(FP), R8
-	MOVQ y+48(FP), R9
-	MOVQ r+56(FP), CX	// c = r
-	MOVQ z_len+8(FP), R11
-	MOVQ $0, BX		// i = 0
-
-	CMPQ R11, $4
-	JL E5
-
-U5:	// i+4 <= n
-	// regular loop body unrolled 4x
-	MOVQ (0*8)(R8)(BX*8), AX
-	MULQ R9
-	ADDQ CX, AX
-	ADCQ $0, DX
-	MOVQ AX, (0*8)(R10)(BX*8)
-	MOVQ DX, CX
-	MOVQ (1*8)(R8)(BX*8), AX
-	MULQ R9
-	ADDQ CX, AX
-	ADCQ $0, DX
-	MOVQ AX, (1*8)(R10)(BX*8)
-	MOVQ DX, CX
-	MOVQ (2*8)(R8)(BX*8), AX
-	MULQ R9
-	ADDQ CX, AX
-	ADCQ $0, DX
-	MOVQ AX, (2*8)(R10)(BX*8)
-	MOVQ DX, CX
-	MOVQ (3*8)(R8)(BX*8), AX
-	MULQ R9
-	ADDQ CX, AX
-	ADCQ $0, DX
-	MOVQ AX, (3*8)(R10)(BX*8)
-	MOVQ DX, CX
-	ADDQ $4, BX		// i += 4
-
-	LEAQ 4(BX), DX
-	CMPQ DX, R11
-	JLE U5
-	JMP E5
-
-L5:	MOVQ (R8)(BX*8), AX
-	MULQ R9
-	ADDQ CX, AX
-	ADCQ $0, DX
-	MOVQ AX, (R10)(BX*8)
-	MOVQ DX, CX
-	ADDQ $1, BX		// i++
-
-E5:	CMPQ BX, R11		// i < n
-	JL L5
-
-	MOVQ CX, c+64(FP)
-	RET
-
-
-// func addMulVVW(z, x []Word, y Word) (c Word)
-TEXT ·addMulVVW(SB),NOSPLIT,$0
-	CMPB ·support_adx(SB), $1
-	JEQ adx
-	MOVQ z+0(FP), R10
-	MOVQ x+24(FP), R8
-	MOVQ y+48(FP), R9
-	MOVQ z_len+8(FP), R11
-	MOVQ $0, BX		// i = 0
-	MOVQ $0, CX		// c = 0
-	MOVQ R11, R12
-	ANDQ $-2, R12
-	CMPQ R11, $2
-	JAE A6
-	JMP E6
-
-A6:
-	MOVQ (R8)(BX*8), AX
-	MULQ R9
-	ADDQ (R10)(BX*8), AX
-	ADCQ $0, DX
-	ADDQ CX, AX
-	ADCQ $0, DX
-	MOVQ DX, CX
-	MOVQ AX, (R10)(BX*8)
-
-	MOVQ (8)(R8)(BX*8), AX
-	MULQ R9
-	ADDQ (8)(R10)(BX*8), AX
-	ADCQ $0, DX
-	ADDQ CX, AX
-	ADCQ $0, DX
-	MOVQ DX, CX
-	MOVQ AX, (8)(R10)(BX*8)
-
-	ADDQ $2, BX
-	CMPQ BX, R12
-	JL A6
-	JMP E6
-
-L6:	MOVQ (R8)(BX*8), AX
-	MULQ R9
-	ADDQ CX, AX
-	ADCQ $0, DX
-	ADDQ AX, (R10)(BX*8)
-	ADCQ $0, DX
-	MOVQ DX, CX
-	ADDQ $1, BX		// i++
-
-E6:	CMPQ BX, R11		// i < n
-	JL L6
-
-	MOVQ CX, c+56(FP)
-	RET
-
-adx:
-	MOVQ z_len+8(FP), R11
-	MOVQ z+0(FP), R10
-	MOVQ x+24(FP), R8
-	MOVQ y+48(FP), DX
-	MOVQ $0, BX   // i = 0
-	MOVQ $0, CX   // carry
-	CMPQ R11, $8
-	JAE  adx_loop_header
-	CMPQ BX, R11
-	JL adx_short
-	MOVQ CX, c+56(FP)
-	RET
-
-adx_loop_header:
-	MOVQ  R11, R13
-	ANDQ  $-8, R13
-adx_loop:
-	XORQ  R9, R9  // unset flags
-	MULXQ (R8), SI, DI
-	ADCXQ CX,SI
-	ADOXQ (R10), SI
-	MOVQ  SI,(R10)
-
-	MULXQ 8(R8), AX, CX
-	ADCXQ DI, AX
-	ADOXQ 8(R10), AX
-	MOVQ  AX, 8(R10)
-
-	MULXQ 16(R8), SI, DI
-	ADCXQ CX, SI
-	ADOXQ 16(R10), SI
-	MOVQ  SI, 16(R10)
-
-	MULXQ 24(R8), AX, CX
-	ADCXQ DI, AX
-	ADOXQ 24(R10), AX
-	MOVQ  AX, 24(R10)
-
-	MULXQ 32(R8), SI, DI
-	ADCXQ CX, SI
-	ADOXQ 32(R10), SI
-	MOVQ  SI, 32(R10)
-
-	MULXQ 40(R8), AX, CX
-	ADCXQ DI, AX
-	ADOXQ 40(R10), AX
-	MOVQ  AX, 40(R10)
-
-	MULXQ 48(R8), SI, DI
-	ADCXQ CX, SI
-	ADOXQ 48(R10), SI
-	MOVQ  SI, 48(R10)
-
-	MULXQ 56(R8), AX, CX
-	ADCXQ DI, AX
-	ADOXQ 56(R10), AX
-	MOVQ  AX, 56(R10)
-
-	ADCXQ R9, CX
-	ADOXQ R9, CX
-
-	ADDQ $64, R8
-	ADDQ $64, R10
-	ADDQ $8, BX
-
-	CMPQ BX, R13
-	JL adx_loop
-	MOVQ z+0(FP), R10
-	MOVQ x+24(FP), R8
-	CMPQ BX, R11
-	JL adx_short
-	MOVQ CX, c+56(FP)
-	RET
-
-adx_short:
-	MULXQ (R8)(BX*8), SI, DI
-	ADDQ CX, SI
-	ADCQ $0, DI
-	ADDQ SI, (R10)(BX*8)
-	ADCQ $0, DI
-	MOVQ DI, CX
-	ADDQ $1, BX		// i++
-
-	CMPQ BX, R11
-	JL adx_short
-
-	MOVQ CX, c+56(FP)
-	RET
-
-
-
diff --git a/contrib/go/_std_1.18/src/math/big/arith_decl.go b/contrib/go/_std_1.18/src/math/big/arith_decl.go
deleted file mode 100644
index eea3d6b325..0000000000
--- a/contrib/go/_std_1.18/src/math/big/arith_decl.go
+++ /dev/null
@@ -1,19 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build !math_big_pure_go
-// +build !math_big_pure_go
-
-package big
-
-// implemented in arith_$GOARCH.s
-func mulWW(x, y Word) (z1, z0 Word)
-func addVV(z, x, y []Word) (c Word)
-func subVV(z, x, y []Word) (c Word)
-func addVW(z, x []Word, y Word) (c Word)
-func subVW(z, x []Word, y Word) (c Word)
-func shlVU(z, x []Word, s uint) (c Word)
-func shrVU(z, x []Word, s uint) (c Word)
-func mulAddVWW(z, x []Word, y, r Word) (c Word)
-func addMulVVW(z, x []Word, y Word) (c Word)
diff --git a/contrib/go/_std_1.18/src/math/big/float.go b/contrib/go/_std_1.18/src/math/big/float.go
deleted file mode 100644
index a8c91a6e54..0000000000
--- a/contrib/go/_std_1.18/src/math/big/float.go
+++ /dev/null
@@ -1,1732 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file implements multi-precision floating-point numbers.
-// Like in the GNU MPFR library (https://www.mpfr.org/), operands
-// can be of mixed precision. Unlike MPFR, the rounding mode is
-// not specified with each operation, but with each operand. The
-// rounding mode of the result operand determines the rounding
-// mode of an operation. This is a from-scratch implementation.
-
-package big
-
-import (
-	"fmt"
-	"math"
-	"math/bits"
-)
-
-const debugFloat = false // enable for debugging
-
-// A nonzero finite Float represents a multi-precision floating point number
-//
-//   sign × mantissa × 2**exponent
-//
-// with 0.5 <= mantissa < 1.0, and MinExp <= exponent <= MaxExp.
-// A Float may also be zero (+0, -0) or infinite (+Inf, -Inf).
-// All Floats are ordered, and the ordering of two Floats x and y
-// is defined by x.Cmp(y).
-//
-// Each Float value also has a precision, rounding mode, and accuracy.
-// The precision is the maximum number of mantissa bits available to
-// represent the value. The rounding mode specifies how a result should
-// be rounded to fit into the mantissa bits, and accuracy describes the
-// rounding error with respect to the exact result.
-//
-// Unless specified otherwise, all operations (including setters) that
-// specify a *Float variable for the result (usually via the receiver
-// with the exception of MantExp), round the numeric result according
-// to the precision and rounding mode of the result variable.
-//
-// If the provided result precision is 0 (see below), it is set to the
-// precision of the argument with the largest precision value before any
-// rounding takes place, and the rounding mode remains unchanged. Thus,
-// uninitialized Floats provided as result arguments will have their
-// precision set to a reasonable value determined by the operands, and
-// their mode is the zero value for RoundingMode (ToNearestEven).
-//
-// By setting the desired precision to 24 or 53 and using matching rounding
-// mode (typically ToNearestEven), Float operations produce the same results
-// as the corresponding float32 or float64 IEEE-754 arithmetic for operands
-// that correspond to normal (i.e., not denormal) float32 or float64 numbers.
-// Exponent underflow and overflow lead to a 0 or an Infinity for different
-// values than IEEE-754 because Float exponents have a much larger range.
-//
-// The zero (uninitialized) value for a Float is ready to use and represents
-// the number +0.0 exactly, with precision 0 and rounding mode ToNearestEven.
-//
-// Operations always take pointer arguments (*Float) rather
-// than Float values, and each unique Float value requires
-// its own unique *Float pointer. To "copy" a Float value,
-// an existing (or newly allocated) Float must be set to
-// a new value using the Float.Set method; shallow copies
-// of Floats are not supported and may lead to errors.
-type Float struct {
-	prec uint32
-	mode RoundingMode
-	acc  Accuracy
-	form form
-	neg  bool
-	mant nat
-	exp  int32
-}
-
-// An ErrNaN panic is raised by a Float operation that would lead to
-// a NaN under IEEE-754 rules. An ErrNaN implements the error interface.
-type ErrNaN struct {
-	msg string
-}
-
-func (err ErrNaN) Error() string {
-	return err.msg
-}
-
-// NewFloat allocates and returns a new Float set to x,
-// with precision 53 and rounding mode ToNearestEven.
-// NewFloat panics with ErrNaN if x is a NaN.
-func NewFloat(x float64) *Float {
-	if math.IsNaN(x) {
-		panic(ErrNaN{"NewFloat(NaN)"})
-	}
-	return new(Float).SetFloat64(x)
-}
-
-// Exponent and precision limits.
-const (
-	MaxExp  = math.MaxInt32  // largest supported exponent
-	MinExp  = math.MinInt32  // smallest supported exponent
-	MaxPrec = math.MaxUint32 // largest (theoretically) supported precision; likely memory-limited
-)
-
-// Internal representation: The mantissa bits x.mant of a nonzero finite
-// Float x are stored in a nat slice long enough to hold up to x.prec bits;
-// the slice may (but doesn't have to) be shorter if the mantissa contains
-// trailing 0 bits. x.mant is normalized if the msb of x.mant == 1 (i.e.,
-// the msb is shifted all the way "to the left"). Thus, if the mantissa has
-// trailing 0 bits or x.prec is not a multiple of the Word size _W,
-// x.mant[0] has trailing zero bits. The msb of the mantissa corresponds
-// to the value 0.5; the exponent x.exp shifts the binary point as needed.
-//
-// A zero or non-finite Float x ignores x.mant and x.exp.
-//
-// x                 form      neg      mant         exp
-// ----------------------------------------------------------
-// ±0                zero      sign     -            -
-// 0 < |x| < +Inf    finite    sign     mantissa     exponent
-// ±Inf              inf       sign     -            -
-
-// A form value describes the internal representation.
-type form byte
-
-// The form value order is relevant - do not change!
-const (
-	zero form = iota
-	finite
-	inf
-)
-
-// RoundingMode determines how a Float value is rounded to the
-// desired precision. Rounding may change the Float value; the
-// rounding error is described by the Float's Accuracy.
-type RoundingMode byte
-
-// These constants define supported rounding modes.
-const (
-	ToNearestEven RoundingMode = iota // == IEEE 754-2008 roundTiesToEven
-	ToNearestAway                     // == IEEE 754-2008 roundTiesToAway
-	ToZero                            // == IEEE 754-2008 roundTowardZero
-	AwayFromZero                      // no IEEE 754-2008 equivalent
-	ToNegativeInf                     // == IEEE 754-2008 roundTowardNegative
-	ToPositiveInf                     // == IEEE 754-2008 roundTowardPositive
-)
-
-//go:generate stringer -type=RoundingMode
-
-// Accuracy describes the rounding error produced by the most recent
-// operation that generated a Float value, relative to the exact value.
-type Accuracy int8
-
-// Constants describing the Accuracy of a Float.
-const (
-	Below Accuracy = -1
-	Exact Accuracy = 0
-	Above Accuracy = +1
-)
-
-//go:generate stringer -type=Accuracy
-
-// SetPrec sets z's precision to prec and returns the (possibly) rounded
-// value of z. Rounding occurs according to z's rounding mode if the mantissa
-// cannot be represented in prec bits without loss of precision.
-// SetPrec(0) maps all finite values to ±0; infinite values remain unchanged.
-// If prec > MaxPrec, it is set to MaxPrec.
-func (z *Float) SetPrec(prec uint) *Float {
-	z.acc = Exact // optimistically assume no rounding is needed
-
-	// special case
-	if prec == 0 {
-		z.prec = 0
-		if z.form == finite {
-			// truncate z to 0
-			z.acc = makeAcc(z.neg)
-			z.form = zero
-		}
-		return z
-	}
-
-	// general case
-	if prec > MaxPrec {
-		prec = MaxPrec
-	}
-	old := z.prec
-	z.prec = uint32(prec)
-	if z.prec < old {
-		z.round(0)
-	}
-	return z
-}
-
-func makeAcc(above bool) Accuracy {
-	if above {
-		return Above
-	}
-	return Below
-}
-
-// SetMode sets z's rounding mode to mode and returns an exact z.
-// z remains unchanged otherwise.
-// z.SetMode(z.Mode()) is a cheap way to set z's accuracy to Exact.
-func (z *Float) SetMode(mode RoundingMode) *Float {
-	z.mode = mode
-	z.acc = Exact
-	return z
-}
-
-// Prec returns the mantissa precision of x in bits.
-// The result may be 0 for |x| == 0 and |x| == Inf.
-func (x *Float) Prec() uint {
-	return uint(x.prec)
-}
-
-// MinPrec returns the minimum precision required to represent x exactly
-// (i.e., the smallest prec before x.SetPrec(prec) would start rounding x).
-// The result is 0 for |x| == 0 and |x| == Inf.
-func (x *Float) MinPrec() uint {
-	if x.form != finite {
-		return 0
-	}
-	return uint(len(x.mant))*_W - x.mant.trailingZeroBits()
-}
-
-// Mode returns the rounding mode of x.
-func (x *Float) Mode() RoundingMode {
-	return x.mode
-}
-
-// Acc returns the accuracy of x produced by the most recent
-// operation, unless explicitly documented otherwise by that
-// operation.
-func (x *Float) Acc() Accuracy {
-	return x.acc
-}
-
-// Sign returns:
-//
-//	-1 if x <   0
-//	 0 if x is ±0
-//	+1 if x >   0
-//
-func (x *Float) Sign() int {
-	if debugFloat {
-		x.validate()
-	}
-	if x.form == zero {
-		return 0
-	}
-	if x.neg {
-		return -1
-	}
-	return 1
-}
-
-// MantExp breaks x into its mantissa and exponent components
-// and returns the exponent. If a non-nil mant argument is
-// provided its value is set to the mantissa of x, with the
-// same precision and rounding mode as x. The components
-// satisfy x == mant × 2**exp, with 0.5 <= |mant| < 1.0.
-// Calling MantExp with a nil argument is an efficient way to
-// get the exponent of the receiver.
-//
-// Special cases are:
-//
-//	(  ±0).MantExp(mant) = 0, with mant set to   ±0
-//	(±Inf).MantExp(mant) = 0, with mant set to ±Inf
-//
-// x and mant may be the same in which case x is set to its
-// mantissa value.
-func (x *Float) MantExp(mant *Float) (exp int) {
-	if debugFloat {
-		x.validate()
-	}
-	if x.form == finite {
-		exp = int(x.exp)
-	}
-	if mant != nil {
-		mant.Copy(x)
-		if mant.form == finite {
-			mant.exp = 0
-		}
-	}
-	return
-}
-
-func (z *Float) setExpAndRound(exp int64, sbit uint) {
-	if exp < MinExp {
-		// underflow
-		z.acc = makeAcc(z.neg)
-		z.form = zero
-		return
-	}
-
-	if exp > MaxExp {
-		// overflow
-		z.acc = makeAcc(!z.neg)
-		z.form = inf
-		return
-	}
-
-	z.form = finite
-	z.exp = int32(exp)
-	z.round(sbit)
-}
-
-// SetMantExp sets z to mant × 2**exp and returns z.
-// The result z has the same precision and rounding mode
-// as mant. SetMantExp is an inverse of MantExp but does
-// not require 0.5 <= |mant| < 1.0. Specifically, for a
-// given x of type *Float, SetMantExp relates to MantExp
-// as follows:
-//
-//	mant := new(Float)
-//	new(Float).SetMantExp(mant, x.MantExp(mant)).Cmp(x) == 0
-//
-// Special cases are:
-//
-//	z.SetMantExp(  ±0, exp) =   ±0
-//	z.SetMantExp(±Inf, exp) = ±Inf
-//
-// z and mant may be the same in which case z's exponent
-// is set to exp.
-func (z *Float) SetMantExp(mant *Float, exp int) *Float {
-	if debugFloat {
-		z.validate()
-		mant.validate()
-	}
-	z.Copy(mant)
-
-	if z.form == finite {
-		// 0 < |mant| < +Inf
-		z.setExpAndRound(int64(z.exp)+int64(exp), 0)
-	}
-	return z
-}
-
-// Signbit reports whether x is negative or negative zero.
-func (x *Float) Signbit() bool {
-	return x.neg
-}
-
-// IsInf reports whether x is +Inf or -Inf.
-func (x *Float) IsInf() bool {
-	return x.form == inf
-}
-
-// IsInt reports whether x is an integer.
-// ±Inf values are not integers.
-func (x *Float) IsInt() bool {
-	if debugFloat {
-		x.validate()
-	}
-	// special cases
-	if x.form != finite {
-		return x.form == zero
-	}
-	// x.form == finite
-	if x.exp <= 0 {
-		return false
-	}
-	// x.exp > 0
-	return x.prec <= uint32(x.exp) || x.MinPrec() <= uint(x.exp) // not enough bits for fractional mantissa
-}
-
-// debugging support
-func (x *Float) validate() {
-	if !debugFloat {
-		// avoid performance bugs
-		panic("validate called but debugFloat is not set")
-	}
-	if x.form != finite {
-		return
-	}
-	m := len(x.mant)
-	if m == 0 {
-		panic("nonzero finite number with empty mantissa")
-	}
-	const msb = 1 << (_W - 1)
-	if x.mant[m-1]&msb == 0 {
-		panic(fmt.Sprintf("msb not set in last word %#x of %s", x.mant[m-1], x.Text('p', 0)))
-	}
-	if x.prec == 0 {
-		panic("zero precision finite number")
-	}
-}
-
-// round rounds z according to z.mode to z.prec bits and sets z.acc accordingly.
-// sbit must be 0 or 1 and summarizes any "sticky bit" information one might
-// have before calling round. z's mantissa must be normalized (with the msb set)
-// or empty.
-//
-// CAUTION: The rounding modes ToNegativeInf, ToPositiveInf are affected by the
-// sign of z. For correct rounding, the sign of z must be set correctly before
-// calling round.
-func (z *Float) round(sbit uint) {
-	if debugFloat {
-		z.validate()
-	}
-
-	z.acc = Exact
-	if z.form != finite {
-		// ±0 or ±Inf => nothing left to do
-		return
-	}
-	// z.form == finite && len(z.mant) > 0
-	// m > 0 implies z.prec > 0 (checked by validate)
-
-	m := uint32(len(z.mant)) // present mantissa length in words
-	bits := m * _W           // present mantissa bits; bits > 0
-	if bits <= z.prec {
-		// mantissa fits => nothing to do
-		return
-	}
-	// bits > z.prec
-
-	// Rounding is based on two bits: the rounding bit (rbit) and the
-	// sticky bit (sbit). The rbit is the bit immediately before the
-	// z.prec leading mantissa bits (the "0.5"). The sbit is set if any
-	// of the bits before the rbit are set (the "0.25", "0.125", etc.):
-	//
-	//   rbit  sbit  => "fractional part"
-	//
-	//   0     0        == 0
-	//   0     1        >  0  , < 0.5
-	//   1     0        == 0.5
-	//   1     1        >  0.5, < 1.0
-
-	// bits > z.prec: mantissa too large => round
-	r := uint(bits - z.prec - 1) // rounding bit position; r >= 0
-	rbit := z.mant.bit(r) & 1    // rounding bit; be safe and ensure it's a single bit
-	// The sticky bit is only needed for rounding ToNearestEven
-	// or when the rounding bit is zero. Avoid computation otherwise.
-	if sbit == 0 && (rbit == 0 || z.mode == ToNearestEven) {
-		sbit = z.mant.sticky(r)
-	}
-	sbit &= 1 // be safe and ensure it's a single bit
-
-	// cut off extra words
-	n := (z.prec + (_W - 1)) / _W // mantissa length in words for desired precision
-	if m > n {
-		copy(z.mant, z.mant[m-n:]) // move n last words to front
-		z.mant = z.mant[:n]
-	}
-
-	// determine number of trailing zero bits (ntz) and compute lsb mask of mantissa's least-significant word
-	ntz := n*_W - z.prec // 0 <= ntz < _W
-	lsb := Word(1) << ntz
-
-	// round if result is inexact
-	if rbit|sbit != 0 {
-		// Make rounding decision: The result mantissa is truncated ("rounded down")
-		// by default. Decide if we need to increment, or "round up", the (unsigned)
-		// mantissa.
-		inc := false
-		switch z.mode {
-		case ToNegativeInf:
-			inc = z.neg
-		case ToZero:
-			// nothing to do
-		case ToNearestEven:
-			inc = rbit != 0 && (sbit != 0 || z.mant[0]&lsb != 0)
-		case ToNearestAway:
-			inc = rbit != 0
-		case AwayFromZero:
-			inc = true
-		case ToPositiveInf:
-			inc = !z.neg
-		default:
-			panic("unreachable")
-		}
-
-		// A positive result (!z.neg) is Above the exact result if we increment,
-		// and it's Below if we truncate (Exact results require no rounding).
-		// For a negative result (z.neg) it is exactly the opposite.
-		z.acc = makeAcc(inc != z.neg)
-
-		if inc {
-			// add 1 to mantissa
-			if addVW(z.mant, z.mant, lsb) != 0 {
-				// mantissa overflow => adjust exponent
-				if z.exp >= MaxExp {
-					// exponent overflow
-					z.form = inf
-					return
-				}
-				z.exp++
-				// adjust mantissa: divide by 2 to compensate for exponent adjustment
-				shrVU(z.mant, z.mant, 1)
-				// set msb == carry == 1 from the mantissa overflow above
-				const msb = 1 << (_W - 1)
-				z.mant[n-1] |= msb
-			}
-		}
-	}
-
-	// zero out trailing bits in least-significant word
-	z.mant[0] &^= lsb - 1
-
-	if debugFloat {
-		z.validate()
-	}
-}
-
-func (z *Float) setBits64(neg bool, x uint64) *Float {
-	if z.prec == 0 {
-		z.prec = 64
-	}
-	z.acc = Exact
-	z.neg = neg
-	if x == 0 {
-		z.form = zero
-		return z
-	}
-	// x != 0
-	z.form = finite
-	s := bits.LeadingZeros64(x)
-	z.mant = z.mant.setUint64(x << uint(s))
-	z.exp = int32(64 - s) // always fits
-	if z.prec < 64 {
-		z.round(0)
-	}
-	return z
-}
-
-// SetUint64 sets z to the (possibly rounded) value of x and returns z.
-// If z's precision is 0, it is changed to 64 (and rounding will have
-// no effect).
-func (z *Float) SetUint64(x uint64) *Float {
-	return z.setBits64(false, x)
-}
-
-// SetInt64 sets z to the (possibly rounded) value of x and returns z.
-// If z's precision is 0, it is changed to 64 (and rounding will have
-// no effect).
-func (z *Float) SetInt64(x int64) *Float {
-	u := x
-	if u < 0 {
-		u = -u
-	}
-	// We cannot simply call z.SetUint64(uint64(u)) and change
-	// the sign afterwards because the sign affects rounding.
-	return z.setBits64(x < 0, uint64(u))
-}
-
-// SetFloat64 sets z to the (possibly rounded) value of x and returns z.
-// If z's precision is 0, it is changed to 53 (and rounding will have
-// no effect). SetFloat64 panics with ErrNaN if x is a NaN.
-func (z *Float) SetFloat64(x float64) *Float {
-	if z.prec == 0 {
-		z.prec = 53
-	}
-	if math.IsNaN(x) {
-		panic(ErrNaN{"Float.SetFloat64(NaN)"})
-	}
-	z.acc = Exact
-	z.neg = math.Signbit(x) // handle -0, -Inf correctly
-	if x == 0 {
-		z.form = zero
-		return z
-	}
-	if math.IsInf(x, 0) {
-		z.form = inf
-		return z
-	}
-	// normalized x != 0
-	z.form = finite
-	fmant, exp := math.Frexp(x) // get normalized mantissa
-	z.mant = z.mant.setUint64(1<<63 | math.Float64bits(fmant)<<11)
-	z.exp = int32(exp) // always fits
-	if z.prec < 53 {
-		z.round(0)
-	}
-	return z
-}
-
-// fnorm normalizes mantissa m by shifting it to the left
-// such that the msb of the most-significant word (msw) is 1.
-// It returns the shift amount. It assumes that len(m) != 0.
-func fnorm(m nat) int64 {
-	if debugFloat && (len(m) == 0 || m[len(m)-1] == 0) {
-		panic("msw of mantissa is 0")
-	}
-	s := nlz(m[len(m)-1])
-	if s > 0 {
-		c := shlVU(m, m, s)
-		if debugFloat && c != 0 {
-			panic("nlz or shlVU incorrect")
-		}
-	}
-	return int64(s)
-}
-
-// SetInt sets z to the (possibly rounded) value of x and returns z.
-// If z's precision is 0, it is changed to the larger of x.BitLen()
-// or 64 (and rounding will have no effect).
-func (z *Float) SetInt(x *Int) *Float {
-	// TODO(gri) can be more efficient if z.prec > 0
-	// but small compared to the size of x, or if there
-	// are many trailing 0's.
-	bits := uint32(x.BitLen())
-	if z.prec == 0 {
-		z.prec = umax32(bits, 64)
-	}
-	z.acc = Exact
-	z.neg = x.neg
-	if len(x.abs) == 0 {
-		z.form = zero
-		return z
-	}
-	// x != 0
-	z.mant = z.mant.set(x.abs)
-	fnorm(z.mant)
-	z.setExpAndRound(int64(bits), 0)
-	return z
-}
-
-// SetRat sets z to the (possibly rounded) value of x and returns z.
-// If z's precision is 0, it is changed to the largest of a.BitLen(),
-// b.BitLen(), or 64; with x = a/b.
-func (z *Float) SetRat(x *Rat) *Float {
-	if x.IsInt() {
-		return z.SetInt(x.Num())
-	}
-	var a, b Float
-	a.SetInt(x.Num())
-	b.SetInt(x.Denom())
-	if z.prec == 0 {
-		z.prec = umax32(a.prec, b.prec)
-	}
-	return z.Quo(&a, &b)
-}
-
-// SetInf sets z to the infinite Float -Inf if signbit is
-// set, or +Inf if signbit is not set, and returns z. The
-// precision of z is unchanged and the result is always
-// Exact.
-func (z *Float) SetInf(signbit bool) *Float {
-	z.acc = Exact
-	z.form = inf
-	z.neg = signbit
-	return z
-}
-
-// Set sets z to the (possibly rounded) value of x and returns z.
-// If z's precision is 0, it is changed to the precision of x
-// before setting z (and rounding will have no effect).
-// Rounding is performed according to z's precision and rounding
-// mode; and z's accuracy reports the result error relative to the
-// exact (not rounded) result.
-func (z *Float) Set(x *Float) *Float {
-	if debugFloat {
-		x.validate()
-	}
-	z.acc = Exact
-	if z != x {
-		z.form = x.form
-		z.neg = x.neg
-		if x.form == finite {
-			z.exp = x.exp
-			z.mant = z.mant.set(x.mant)
-		}
-		if z.prec == 0 {
-			z.prec = x.prec
-		} else if z.prec < x.prec {
-			z.round(0)
-		}
-	}
-	return z
-}
-
-// Copy sets z to x, with the same precision, rounding mode, and
-// accuracy as x, and returns z. x is not changed even if z and
-// x are the same.
-func (z *Float) Copy(x *Float) *Float {
-	if debugFloat {
-		x.validate()
-	}
-	if z != x {
-		z.prec = x.prec
-		z.mode = x.mode
-		z.acc = x.acc
-		z.form = x.form
-		z.neg = x.neg
-		if z.form == finite {
-			z.mant = z.mant.set(x.mant)
-			z.exp = x.exp
-		}
-	}
-	return z
-}
-
-// msb32 returns the 32 most significant bits of x.
-func msb32(x nat) uint32 {
-	i := len(x) - 1
-	if i < 0 {
-		return 0
-	}
-	if debugFloat && x[i]&(1<<(_W-1)) == 0 {
-		panic("x not normalized")
-	}
-	switch _W {
-	case 32:
-		return uint32(x[i])
-	case 64:
-		return uint32(x[i] >> 32)
-	}
-	panic("unreachable")
-}
-
-// msb64 returns the 64 most significant bits of x.
-func msb64(x nat) uint64 {
-	i := len(x) - 1
-	if i < 0 {
-		return 0
-	}
-	if debugFloat && x[i]&(1<<(_W-1)) == 0 {
-		panic("x not normalized")
-	}
-	switch _W {
-	case 32:
-		v := uint64(x[i]) << 32
-		if i > 0 {
-			v |= uint64(x[i-1])
-		}
-		return v
-	case 64:
-		return uint64(x[i])
-	}
-	panic("unreachable")
-}
-
-// Uint64 returns the unsigned integer resulting from truncating x
-// towards zero. If 0 <= x <= math.MaxUint64, the result is Exact
-// if x is an integer and Below otherwise.
-// The result is (0, Above) for x < 0, and (math.MaxUint64, Below)
-// for x > math.MaxUint64.
-func (x *Float) Uint64() (uint64, Accuracy) {
-	if debugFloat {
-		x.validate()
-	}
-
-	switch x.form {
-	case finite:
-		if x.neg {
-			return 0, Above
-		}
-		// 0 < x < +Inf
-		if x.exp <= 0 {
-			// 0 < x < 1
-			return 0, Below
-		}
-		// 1 <= x < Inf
-		if x.exp <= 64 {
-			// u = trunc(x) fits into a uint64
-			u := msb64(x.mant) >> (64 - uint32(x.exp))
-			if x.MinPrec() <= 64 {
-				return u, Exact
-			}
-			return u, Below // x truncated
-		}
-		// x too large
-		return math.MaxUint64, Below
-
-	case zero:
-		return 0, Exact
-
-	case inf:
-		if x.neg {
-			return 0, Above
-		}
-		return math.MaxUint64, Below
-	}
-
-	panic("unreachable")
-}
-
-// Int64 returns the integer resulting from truncating x towards zero.
-// If math.MinInt64 <= x <= math.MaxInt64, the result is Exact if x is
-// an integer, and Above (x < 0) or Below (x > 0) otherwise.
-// The result is (math.MinInt64, Above) for x < math.MinInt64,
-// and (math.MaxInt64, Below) for x > math.MaxInt64.
-func (x *Float) Int64() (int64, Accuracy) {
-	if debugFloat {
-		x.validate()
-	}
-
-	switch x.form {
-	case finite:
-		// 0 < |x| < +Inf
-		acc := makeAcc(x.neg)
-		if x.exp <= 0 {
-			// 0 < |x| < 1
-			return 0, acc
-		}
-		// x.exp > 0
-
-		// 1 <= |x| < +Inf
-		if x.exp <= 63 {
-			// i = trunc(x) fits into an int64 (excluding math.MinInt64)
-			i := int64(msb64(x.mant) >> (64 - uint32(x.exp)))
-			if x.neg {
-				i = -i
-			}
-			if x.MinPrec() <= uint(x.exp) {
-				return i, Exact
-			}
-			return i, acc // x truncated
-		}
-		if x.neg {
-			// check for special case x == math.MinInt64 (i.e., x == -(0.5 << 64))
-			if x.exp == 64 && x.MinPrec() == 1 {
-				acc = Exact
-			}
-			return math.MinInt64, acc
-		}
-		// x too large
-		return math.MaxInt64, Below
-
-	case zero:
-		return 0, Exact
-
-	case inf:
-		if x.neg {
-			return math.MinInt64, Above
-		}
-		return math.MaxInt64, Below
-	}
-
-	panic("unreachable")
-}
-
-// Float32 returns the float32 value nearest to x. If x is too small to be
-// represented by a float32 (|x| < math.SmallestNonzeroFloat32), the result
-// is (0, Below) or (-0, Above), respectively, depending on the sign of x.
-// If x is too large to be represented by a float32 (|x| > math.MaxFloat32),
-// the result is (+Inf, Above) or (-Inf, Below), depending on the sign of x.
-func (x *Float) Float32() (float32, Accuracy) {
-	if debugFloat {
-		x.validate()
-	}
-
-	switch x.form {
-	case finite:
-		// 0 < |x| < +Inf
-
-		const (
-			fbits = 32                //        float size
-			mbits = 23                //        mantissa size (excluding implicit msb)
-			ebits = fbits - mbits - 1 //     8  exponent size
-			bias  = 1<<(ebits-1) - 1  //   127  exponent bias
-			dmin  = 1 - bias - mbits  //  -149  smallest unbiased exponent (denormal)
-			emin  = 1 - bias          //  -126  smallest unbiased exponent (normal)
-			emax  = bias              //   127  largest unbiased exponent (normal)
-		)
-
-		// Float mantissa m is 0.5 <= m < 1.0; compute exponent e for float32 mantissa.
-		e := x.exp - 1 // exponent for normal mantissa m with 1.0 <= m < 2.0
-
-		// Compute precision p for float32 mantissa.
-		// If the exponent is too small, we have a denormal number before
-		// rounding and fewer than p mantissa bits of precision available
-		// (the exponent remains fixed but the mantissa gets shifted right).
-		p := mbits + 1 // precision of normal float
-		if e < emin {
-			// recompute precision
-			p = mbits + 1 - emin + int(e)
-			// If p == 0, the mantissa of x is shifted so much to the right
-			// that its msb falls immediately to the right of the float32
-			// mantissa space. In other words, if the smallest denormal is
-			// considered "1.0", for p == 0, the mantissa value m is >= 0.5.
-			// If m > 0.5, it is rounded up to 1.0; i.e., the smallest denormal.
-			// If m == 0.5, it is rounded down to even, i.e., 0.0.
-			// If p < 0, the mantissa value m is <= "0.25" which is never rounded up.
-			if p < 0 /* m <= 0.25 */ || p == 0 && x.mant.sticky(uint(len(x.mant))*_W-1) == 0 /* m == 0.5 */ {
-				// underflow to ±0
-				if x.neg {
-					var z float32
-					return -z, Above
-				}
-				return 0.0, Below
-			}
-			// otherwise, round up
-			// We handle p == 0 explicitly because it's easy and because
-			// Float.round doesn't support rounding to 0 bits of precision.
-			if p == 0 {
-				if x.neg {
-					return -math.SmallestNonzeroFloat32, Below
-				}
-				return math.SmallestNonzeroFloat32, Above
-			}
-		}
-		// p > 0
-
-		// round
-		var r Float
-		r.prec = uint32(p)
-		r.Set(x)
-		e = r.exp - 1
-
-		// Rounding may have caused r to overflow to ±Inf
-		// (rounding never causes underflows to 0).
-		// If the exponent is too large, also overflow to ±Inf.
-		if r.form == inf || e > emax {
-			// overflow
-			if x.neg {
-				return float32(math.Inf(-1)), Below
-			}
-			return float32(math.Inf(+1)), Above
-		}
-		// e <= emax
-
-		// Determine sign, biased exponent, and mantissa.
-		var sign, bexp, mant uint32
-		if x.neg {
-			sign = 1 << (fbits - 1)
-		}
-
-		// Rounding may have caused a denormal number to
-		// become normal. Check again.
-		if e < emin {
-			// denormal number: recompute precision
-			// Since rounding may have at best increased precision
-			// and we have eliminated p <= 0 early, we know p > 0.
-			// bexp == 0 for denormals
-			p = mbits + 1 - emin + int(e)
-			mant = msb32(r.mant) >> uint(fbits-p)
-		} else {
-			// normal number: emin <= e <= emax
-			bexp = uint32(e+bias) << mbits
-			mant = msb32(r.mant) >> ebits & (1<<mbits - 1) // cut off msb (implicit 1 bit)
-		}
-
-		return math.Float32frombits(sign | bexp | mant), r.acc
-
-	case zero:
-		if x.neg {
-			var z float32
-			return -z, Exact
-		}
-		return 0.0, Exact
-
-	case inf:
-		if x.neg {
-			return float32(math.Inf(-1)), Exact
-		}
-		return float32(math.Inf(+1)), Exact
-	}
-
-	panic("unreachable")
-}
-
-// Float64 returns the float64 value nearest to x. If x is too small to be
-// represented by a float64 (|x| < math.SmallestNonzeroFloat64), the result
-// is (0, Below) or (-0, Above), respectively, depending on the sign of x.
-// If x is too large to be represented by a float64 (|x| > math.MaxFloat64),
-// the result is (+Inf, Above) or (-Inf, Below), depending on the sign of x.
-func (x *Float) Float64() (float64, Accuracy) {
-	if debugFloat {
-		x.validate()
-	}
-
-	switch x.form {
-	case finite:
-		// 0 < |x| < +Inf
-
-		const (
-			fbits = 64                //        float size
-			mbits = 52                //        mantissa size (excluding implicit msb)
-			ebits = fbits - mbits - 1 //    11  exponent size
-			bias  = 1<<(ebits-1) - 1  //  1023  exponent bias
-			dmin  = 1 - bias - mbits  // -1074  smallest unbiased exponent (denormal)
-			emin  = 1 - bias          // -1022  smallest unbiased exponent (normal)
-			emax  = bias              //  1023  largest unbiased exponent (normal)
-		)
-
-		// Float mantissa m is 0.5 <= m < 1.0; compute exponent e for float64 mantissa.
-		e := x.exp - 1 // exponent for normal mantissa m with 1.0 <= m < 2.0
-
-		// Compute precision p for float64 mantissa.
-		// If the exponent is too small, we have a denormal number before
-		// rounding and fewer than p mantissa bits of precision available
-		// (the exponent remains fixed but the mantissa gets shifted right).
-		p := mbits + 1 // precision of normal float
-		if e < emin {
-			// recompute precision
-			p = mbits + 1 - emin + int(e)
-			// If p == 0, the mantissa of x is shifted so much to the right
-			// that its msb falls immediately to the right of the float64
-			// mantissa space. In other words, if the smallest denormal is
-			// considered "1.0", for p == 0, the mantissa value m is >= 0.5.
-			// If m > 0.5, it is rounded up to 1.0; i.e., the smallest denormal.
-			// If m == 0.5, it is rounded down to even, i.e., 0.0.
-			// If p < 0, the mantissa value m is <= "0.25" which is never rounded up.
-			if p < 0 /* m <= 0.25 */ || p == 0 && x.mant.sticky(uint(len(x.mant))*_W-1) == 0 /* m == 0.5 */ {
-				// underflow to ±0
-				if x.neg {
-					var z float64
-					return -z, Above
-				}
-				return 0.0, Below
-			}
-			// otherwise, round up
-			// We handle p == 0 explicitly because it's easy and because
-			// Float.round doesn't support rounding to 0 bits of precision.
-			if p == 0 {
-				if x.neg {
-					return -math.SmallestNonzeroFloat64, Below
-				}
-				return math.SmallestNonzeroFloat64, Above
-			}
-		}
-		// p > 0
-
-		// round
-		var r Float
-		r.prec = uint32(p)
-		r.Set(x)
-		e = r.exp - 1
-
-		// Rounding may have caused r to overflow to ±Inf
-		// (rounding never causes underflows to 0).
-		// If the exponent is too large, also overflow to ±Inf.
-		if r.form == inf || e > emax {
-			// overflow
-			if x.neg {
-				return math.Inf(-1), Below
-			}
-			return math.Inf(+1), Above
-		}
-		// e <= emax
-
-		// Determine sign, biased exponent, and mantissa.
-		var sign, bexp, mant uint64
-		if x.neg {
-			sign = 1 << (fbits - 1)
-		}
-
-		// Rounding may have caused a denormal number to
-		// become normal. Check again.
-		if e < emin {
-			// denormal number: recompute precision
-			// Since rounding may have at best increased precision
-			// and we have eliminated p <= 0 early, we know p > 0.
-			// bexp == 0 for denormals
-			p = mbits + 1 - emin + int(e)
-			mant = msb64(r.mant) >> uint(fbits-p)
-		} else {
-			// normal number: emin <= e <= emax
-			bexp = uint64(e+bias) << mbits
-			mant = msb64(r.mant) >> ebits & (1<<mbits - 1) // cut off msb (implicit 1 bit)
-		}
-
-		return math.Float64frombits(sign | bexp | mant), r.acc
-
-	case zero:
-		if x.neg {
-			var z float64
-			return -z, Exact
-		}
-		return 0.0, Exact
-
-	case inf:
-		if x.neg {
-			return math.Inf(-1), Exact
-		}
-		return math.Inf(+1), Exact
-	}
-
-	panic("unreachable")
-}
-
-// Int returns the result of truncating x towards zero;
-// or nil if x is an infinity.
-// The result is Exact if x.IsInt(); otherwise it is Below
-// for x > 0, and Above for x < 0.
-// If a non-nil *Int argument z is provided, Int stores
-// the result in z instead of allocating a new Int.
-func (x *Float) Int(z *Int) (*Int, Accuracy) {
-	if debugFloat {
-		x.validate()
-	}
-
-	if z == nil && x.form <= finite {
-		z = new(Int)
-	}
-
-	switch x.form {
-	case finite:
-		// 0 < |x| < +Inf
-		acc := makeAcc(x.neg)
-		if x.exp <= 0 {
-			// 0 < |x| < 1
-			return z.SetInt64(0), acc
-		}
-		// x.exp > 0
-
-		// 1 <= |x| < +Inf
-		// determine minimum required precision for x
-		allBits := uint(len(x.mant)) * _W
-		exp := uint(x.exp)
-		if x.MinPrec() <= exp {
-			acc = Exact
-		}
-		// shift mantissa as needed
-		if z == nil {
-			z = new(Int)
-		}
-		z.neg = x.neg
-		switch {
-		case exp > allBits:
-			z.abs = z.abs.shl(x.mant, exp-allBits)
-		default:
-			z.abs = z.abs.set(x.mant)
-		case exp < allBits:
-			z.abs = z.abs.shr(x.mant, allBits-exp)
-		}
-		return z, acc
-
-	case zero:
-		return z.SetInt64(0), Exact
-
-	case inf:
-		return nil, makeAcc(x.neg)
-	}
-
-	panic("unreachable")
-}
-
-// Rat returns the rational number corresponding to x;
-// or nil if x is an infinity.
-// The result is Exact if x is not an Inf.
-// If a non-nil *Rat argument z is provided, Rat stores
-// the result in z instead of allocating a new Rat.
-func (x *Float) Rat(z *Rat) (*Rat, Accuracy) {
-	if debugFloat {
-		x.validate()
-	}
-
-	if z == nil && x.form <= finite {
-		z = new(Rat)
-	}
-
-	switch x.form {
-	case finite:
-		// 0 < |x| < +Inf
-		allBits := int32(len(x.mant)) * _W
-		// build up numerator and denominator
-		z.a.neg = x.neg
-		switch {
-		case x.exp > allBits:
-			z.a.abs = z.a.abs.shl(x.mant, uint(x.exp-allBits))
-			z.b.abs = z.b.abs[:0] // == 1 (see Rat)
-			// z already in normal form
-		default:
-			z.a.abs = z.a.abs.set(x.mant)
-			z.b.abs = z.b.abs[:0] // == 1 (see Rat)
-			// z already in normal form
-		case x.exp < allBits:
-			z.a.abs = z.a.abs.set(x.mant)
-			t := z.b.abs.setUint64(1)
-			z.b.abs = t.shl(t, uint(allBits-x.exp))
-			z.norm()
-		}
-		return z, Exact
-
-	case zero:
-		return z.SetInt64(0), Exact
-
-	case inf:
-		return nil, makeAcc(x.neg)
-	}
-
-	panic("unreachable")
-}
-
-// Abs sets z to the (possibly rounded) value |x| (the absolute value of x)
-// and returns z.
-func (z *Float) Abs(x *Float) *Float {
-	z.Set(x)
-	z.neg = false
-	return z
-}
-
-// Neg sets z to the (possibly rounded) value of x with its sign negated,
-// and returns z.
-func (z *Float) Neg(x *Float) *Float {
-	z.Set(x)
-	z.neg = !z.neg
-	return z
-}
-
-func validateBinaryOperands(x, y *Float) {
-	if !debugFloat {
-		// avoid performance bugs
-		panic("validateBinaryOperands called but debugFloat is not set")
-	}
-	if len(x.mant) == 0 {
-		panic("empty mantissa for x")
-	}
-	if len(y.mant) == 0 {
-		panic("empty mantissa for y")
-	}
-}
-
-// z = x + y, ignoring signs of x and y for the addition
-// but using the sign of z for rounding the result.
-// x and y must have a non-empty mantissa and valid exponent.
-func (z *Float) uadd(x, y *Float) {
-	// Note: This implementation requires 2 shifts most of the
-	// time. It is also inefficient if exponents or precisions
-	// differ by wide margins. The following article describes
-	// an efficient (but much more complicated) implementation
-	// compatible with the internal representation used here:
-	//
-	// Vincent Lefèvre: "The Generic Multiple-Precision Floating-
-	// Point Addition With Exact Rounding (as in the MPFR Library)"
-	// http://www.vinc17.net/research/papers/rnc6.pdf
-
-	if debugFloat {
-		validateBinaryOperands(x, y)
-	}
-
-	// compute exponents ex, ey for mantissa with "binary point"
-	// on the right (mantissa.0) - use int64 to avoid overflow
-	ex := int64(x.exp) - int64(len(x.mant))*_W
-	ey := int64(y.exp) - int64(len(y.mant))*_W
-
-	al := alias(z.mant, x.mant) || alias(z.mant, y.mant)
-
-	// TODO(gri) having a combined add-and-shift primitive
-	//           could make this code significantly faster
-	switch {
-	case ex < ey:
-		if al {
-			t := nat(nil).shl(y.mant, uint(ey-ex))
-			z.mant = z.mant.add(x.mant, t)
-		} else {
-			z.mant = z.mant.shl(y.mant, uint(ey-ex))
-			z.mant = z.mant.add(x.mant, z.mant)
-		}
-	default:
-		// ex == ey, no shift needed
-		z.mant = z.mant.add(x.mant, y.mant)
-	case ex > ey:
-		if al {
-			t := nat(nil).shl(x.mant, uint(ex-ey))
-			z.mant = z.mant.add(t, y.mant)
-		} else {
-			z.mant = z.mant.shl(x.mant, uint(ex-ey))
-			z.mant = z.mant.add(z.mant, y.mant)
-		}
-		ex = ey
-	}
-	// len(z.mant) > 0
-
-	z.setExpAndRound(ex+int64(len(z.mant))*_W-fnorm(z.mant), 0)
-}
-
-// z = x - y for |x| > |y|, ignoring signs of x and y for the subtraction
-// but using the sign of z for rounding the result.
-// x and y must have a non-empty mantissa and valid exponent.
-func (z *Float) usub(x, y *Float) {
-	// This code is symmetric to uadd.
-	// We have not factored the common code out because
-	// eventually uadd (and usub) should be optimized
-	// by special-casing, and the code will diverge.
-
-	if debugFloat {
-		validateBinaryOperands(x, y)
-	}
-
-	ex := int64(x.exp) - int64(len(x.mant))*_W
-	ey := int64(y.exp) - int64(len(y.mant))*_W
-
-	al := alias(z.mant, x.mant) || alias(z.mant, y.mant)
-
-	switch {
-	case ex < ey:
-		if al {
-			t := nat(nil).shl(y.mant, uint(ey-ex))
-			z.mant = t.sub(x.mant, t)
-		} else {
-			z.mant = z.mant.shl(y.mant, uint(ey-ex))
-			z.mant = z.mant.sub(x.mant, z.mant)
-		}
-	default:
-		// ex == ey, no shift needed
-		z.mant = z.mant.sub(x.mant, y.mant)
-	case ex > ey:
-		if al {
-			t := nat(nil).shl(x.mant, uint(ex-ey))
-			z.mant = t.sub(t, y.mant)
-		} else {
-			z.mant = z.mant.shl(x.mant, uint(ex-ey))
-			z.mant = z.mant.sub(z.mant, y.mant)
-		}
-		ex = ey
-	}
-
-	// operands may have canceled each other out
-	if len(z.mant) == 0 {
-		z.acc = Exact
-		z.form = zero
-		z.neg = false
-		return
-	}
-	// len(z.mant) > 0
-
-	z.setExpAndRound(ex+int64(len(z.mant))*_W-fnorm(z.mant), 0)
-}
-
-// z = x * y, ignoring signs of x and y for the multiplication
-// but using the sign of z for rounding the result.
-// x and y must have a non-empty mantissa and valid exponent.
-func (z *Float) umul(x, y *Float) {
-	if debugFloat {
-		validateBinaryOperands(x, y)
-	}
-
-	// Note: This is doing too much work if the precision
-	// of z is less than the sum of the precisions of x
-	// and y which is often the case (e.g., if all floats
-	// have the same precision).
-	// TODO(gri) Optimize this for the common case.
-
-	e := int64(x.exp) + int64(y.exp)
-	if x == y {
-		z.mant = z.mant.sqr(x.mant)
-	} else {
-		z.mant = z.mant.mul(x.mant, y.mant)
-	}
-	z.setExpAndRound(e-fnorm(z.mant), 0)
-}
-
-// z = x / y, ignoring signs of x and y for the division
-// but using the sign of z for rounding the result.
-// x and y must have a non-empty mantissa and valid exponent.
-func (z *Float) uquo(x, y *Float) {
-	if debugFloat {
-		validateBinaryOperands(x, y)
-	}
-
-	// mantissa length in words for desired result precision + 1
-	// (at least one extra bit so we get the rounding bit after
-	// the division)
-	n := int(z.prec/_W) + 1
-
-	// compute adjusted x.mant such that we get enough result precision
-	xadj := x.mant
-	if d := n - len(x.mant) + len(y.mant); d > 0 {
-		// d extra words needed => add d "0 digits" to x
-		xadj = make(nat, len(x.mant)+d)
-		copy(xadj[d:], x.mant)
-	}
-	// TODO(gri): If we have too many digits (d < 0), we should be able
-	// to shorten x for faster division. But we must be extra careful
-	// with rounding in that case.
-
-	// Compute d before division since there may be aliasing of x.mant
-	// (via xadj) or y.mant with z.mant.
-	d := len(xadj) - len(y.mant)
-
-	// divide
-	var r nat
-	z.mant, r = z.mant.div(nil, xadj, y.mant)
-	e := int64(x.exp) - int64(y.exp) - int64(d-len(z.mant))*_W
-
-	// The result is long enough to include (at least) the rounding bit.
-	// If there's a non-zero remainder, the corresponding fractional part
-	// (if it were computed), would have a non-zero sticky bit (if it were
-	// zero, it couldn't have a non-zero remainder).
-	var sbit uint
-	if len(r) > 0 {
-		sbit = 1
-	}
-
-	z.setExpAndRound(e-fnorm(z.mant), sbit)
-}
-
-// ucmp returns -1, 0, or +1, depending on whether
-// |x| < |y|, |x| == |y|, or |x| > |y|.
-// x and y must have a non-empty mantissa and valid exponent.
-func (x *Float) ucmp(y *Float) int {
-	if debugFloat {
-		validateBinaryOperands(x, y)
-	}
-
-	switch {
-	case x.exp < y.exp:
-		return -1
-	case x.exp > y.exp:
-		return +1
-	}
-	// x.exp == y.exp
-
-	// compare mantissas
-	i := len(x.mant)
-	j := len(y.mant)
-	for i > 0 || j > 0 {
-		var xm, ym Word
-		if i > 0 {
-			i--
-			xm = x.mant[i]
-		}
-		if j > 0 {
-			j--
-			ym = y.mant[j]
-		}
-		switch {
-		case xm < ym:
-			return -1
-		case xm > ym:
-			return +1
-		}
-	}
-
-	return 0
-}
-
-// Handling of sign bit as defined by IEEE 754-2008, section 6.3:
-//
-// When neither the inputs nor result are NaN, the sign of a product or
-// quotient is the exclusive OR of the operands’ signs; the sign of a sum,
-// or of a difference x−y regarded as a sum x+(−y), differs from at most
-// one of the addends’ signs; and the sign of the result of conversions,
-// the quantize operation, the roundToIntegral operations, and the
-// roundToIntegralExact (see 5.3.1) is the sign of the first or only operand.
-// These rules shall apply even when operands or results are zero or infinite.
-//
-// When the sum of two operands with opposite signs (or the difference of
-// two operands with like signs) is exactly zero, the sign of that sum (or
-// difference) shall be +0 in all rounding-direction attributes except
-// roundTowardNegative; under that attribute, the sign of an exact zero
-// sum (or difference) shall be −0. However, x+x = x−(−x) retains the same
-// sign as x even when x is zero.
-//
-// See also: https://play.golang.org/p/RtH3UCt5IH
-
-// Add sets z to the rounded sum x+y and returns z. If z's precision is 0,
-// it is changed to the larger of x's or y's precision before the operation.
-// Rounding is performed according to z's precision and rounding mode; and
-// z's accuracy reports the result error relative to the exact (not rounded)
-// result. Add panics with ErrNaN if x and y are infinities with opposite
-// signs. The value of z is undefined in that case.
-func (z *Float) Add(x, y *Float) *Float {
-	if debugFloat {
-		x.validate()
-		y.validate()
-	}
-
-	if z.prec == 0 {
-		z.prec = umax32(x.prec, y.prec)
-	}
-
-	if x.form == finite && y.form == finite {
-		// x + y (common case)
-
-		// Below we set z.neg = x.neg, and when z aliases y this will
-		// change the y operand's sign. This is fine, because if an
-		// operand aliases the receiver it'll be overwritten, but we still
-		// want the original x.neg and y.neg values when we evaluate
-		// x.neg != y.neg, so we need to save y.neg before setting z.neg.
-		yneg := y.neg
-
-		z.neg = x.neg
-		if x.neg == yneg {
-			// x + y == x + y
-			// (-x) + (-y) == -(x + y)
-			z.uadd(x, y)
-		} else {
-			// x + (-y) == x - y == -(y - x)
-			// (-x) + y == y - x == -(x - y)
-			if x.ucmp(y) > 0 {
-				z.usub(x, y)
-			} else {
-				z.neg = !z.neg
-				z.usub(y, x)
-			}
-		}
-		if z.form == zero && z.mode == ToNegativeInf && z.acc == Exact {
-			z.neg = true
-		}
-		return z
-	}
-
-	if x.form == inf && y.form == inf && x.neg != y.neg {
-		// +Inf + -Inf
-		// -Inf + +Inf
-		// value of z is undefined but make sure it's valid
-		z.acc = Exact
-		z.form = zero
-		z.neg = false
-		panic(ErrNaN{"addition of infinities with opposite signs"})
-	}
-
-	if x.form == zero && y.form == zero {
-		// ±0 + ±0
-		z.acc = Exact
-		z.form = zero
-		z.neg = x.neg && y.neg // -0 + -0 == -0
-		return z
-	}
-
-	if x.form == inf || y.form == zero {
-		// ±Inf + y
-		// x + ±0
-		return z.Set(x)
-	}
-
-	// ±0 + y
-	// x + ±Inf
-	return z.Set(y)
-}
-
-// Sub sets z to the rounded difference x-y and returns z.
-// Precision, rounding, and accuracy reporting are as for Add.
-// Sub panics with ErrNaN if x and y are infinities with equal
-// signs. The value of z is undefined in that case.
-func (z *Float) Sub(x, y *Float) *Float {
-	if debugFloat {
-		x.validate()
-		y.validate()
-	}
-
-	if z.prec == 0 {
-		z.prec = umax32(x.prec, y.prec)
-	}
-
-	if x.form == finite && y.form == finite {
-		// x - y (common case)
-		yneg := y.neg
-		z.neg = x.neg
-		if x.neg != yneg {
-			// x - (-y) == x + y
-			// (-x) - y == -(x + y)
-			z.uadd(x, y)
-		} else {
-			// x - y == x - y == -(y - x)
-			// (-x) - (-y) == y - x == -(x - y)
-			if x.ucmp(y) > 0 {
-				z.usub(x, y)
-			} else {
-				z.neg = !z.neg
-				z.usub(y, x)
-			}
-		}
-		if z.form == zero && z.mode == ToNegativeInf && z.acc == Exact {
-			z.neg = true
-		}
-		return z
-	}
-
-	if x.form == inf && y.form == inf && x.neg == y.neg {
-		// +Inf - +Inf
-		// -Inf - -Inf
-		// value of z is undefined but make sure it's valid
-		z.acc = Exact
-		z.form = zero
-		z.neg = false
-		panic(ErrNaN{"subtraction of infinities with equal signs"})
-	}
-
-	if x.form == zero && y.form == zero {
-		// ±0 - ±0
-		z.acc = Exact
-		z.form = zero
-		z.neg = x.neg && !y.neg // -0 - +0 == -0
-		return z
-	}
-
-	if x.form == inf || y.form == zero {
-		// ±Inf - y
-		// x - ±0
-		return z.Set(x)
-	}
-
-	// ±0 - y
-	// x - ±Inf
-	return z.Neg(y)
-}
-
-// Mul sets z to the rounded product x*y and returns z.
-// Precision, rounding, and accuracy reporting are as for Add.
-// Mul panics with ErrNaN if one operand is zero and the other
-// operand an infinity. The value of z is undefined in that case.
-func (z *Float) Mul(x, y *Float) *Float {
-	if debugFloat {
-		x.validate()
-		y.validate()
-	}
-
-	if z.prec == 0 {
-		z.prec = umax32(x.prec, y.prec)
-	}
-
-	z.neg = x.neg != y.neg
-
-	if x.form == finite && y.form == finite {
-		// x * y (common case)
-		z.umul(x, y)
-		return z
-	}
-
-	z.acc = Exact
-	if x.form == zero && y.form == inf || x.form == inf && y.form == zero {
-		// ±0 * ±Inf
-		// ±Inf * ±0
-		// value of z is undefined but make sure it's valid
-		z.form = zero
-		z.neg = false
-		panic(ErrNaN{"multiplication of zero with infinity"})
-	}
-
-	if x.form == inf || y.form == inf {
-		// ±Inf * y
-		// x * ±Inf
-		z.form = inf
-		return z
-	}
-
-	// ±0 * y
-	// x * ±0
-	z.form = zero
-	return z
-}
-
-// Quo sets z to the rounded quotient x/y and returns z.
-// Precision, rounding, and accuracy reporting are as for Add.
-// Quo panics with ErrNaN if both operands are zero or infinities.
-// The value of z is undefined in that case.
-func (z *Float) Quo(x, y *Float) *Float {
-	if debugFloat {
-		x.validate()
-		y.validate()
-	}
-
-	if z.prec == 0 {
-		z.prec = umax32(x.prec, y.prec)
-	}
-
-	z.neg = x.neg != y.neg
-
-	if x.form == finite && y.form == finite {
-		// x / y (common case)
-		z.uquo(x, y)
-		return z
-	}
-
-	z.acc = Exact
-	if x.form == zero && y.form == zero || x.form == inf && y.form == inf {
-		// ±0 / ±0
-		// ±Inf / ±Inf
-		// value of z is undefined but make sure it's valid
-		z.form = zero
-		z.neg = false
-		panic(ErrNaN{"division of zero by zero or infinity by infinity"})
-	}
-
-	if x.form == zero || y.form == inf {
-		// ±0 / y
-		// x / ±Inf
-		z.form = zero
-		return z
-	}
-
-	// x / ±0
-	// ±Inf / y
-	z.form = inf
-	return z
-}
-
-// Cmp compares x and y and returns:
-//
-//   -1 if x <  y
-//    0 if x == y (incl. -0 == 0, -Inf == -Inf, and +Inf == +Inf)
-//   +1 if x >  y
-//
-func (x *Float) Cmp(y *Float) int {
-	if debugFloat {
-		x.validate()
-		y.validate()
-	}
-
-	mx := x.ord()
-	my := y.ord()
-	switch {
-	case mx < my:
-		return -1
-	case mx > my:
-		return +1
-	}
-	// mx == my
-
-	// only if |mx| == 1 we have to compare the mantissae
-	switch mx {
-	case -1:
-		return y.ucmp(x)
-	case +1:
-		return x.ucmp(y)
-	}
-
-	return 0
-}
-
-// ord classifies x and returns:
-//
-//	-2 if -Inf == x
-//	-1 if -Inf < x < 0
-//	 0 if x == 0 (signed or unsigned)
-//	+1 if 0 < x < +Inf
-//	+2 if x == +Inf
-//
-func (x *Float) ord() int {
-	var m int
-	switch x.form {
-	case finite:
-		m = 1
-	case zero:
-		return 0
-	case inf:
-		m = 2
-	}
-	if x.neg {
-		m = -m
-	}
-	return m
-}
-
-func umax32(x, y uint32) uint32 {
-	if x > y {
-		return x
-	}
-	return y
-}
diff --git a/contrib/go/_std_1.18/src/math/big/floatconv.go b/contrib/go/_std_1.18/src/math/big/floatconv.go
deleted file mode 100644
index 57b7df3936..0000000000
--- a/contrib/go/_std_1.18/src/math/big/floatconv.go
+++ /dev/null
@@ -1,304 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file implements string-to-Float conversion functions.
-
-package big
-
-import (
-	"fmt"
-	"io"
-	"strings"
-)
-
-var floatZero Float
-
-// SetString sets z to the value of s and returns z and a boolean indicating
-// success. s must be a floating-point number of the same format as accepted
-// by Parse, with base argument 0. The entire string (not just a prefix) must
-// be valid for success. If the operation failed, the value of z is undefined
-// but the returned value is nil.
-func (z *Float) SetString(s string) (*Float, bool) {
-	if f, _, err := z.Parse(s, 0); err == nil {
-		return f, true
-	}
-	return nil, false
-}
-
-// scan is like Parse but reads the longest possible prefix representing a valid
-// floating point number from an io.ByteScanner rather than a string. It serves
-// as the implementation of Parse. It does not recognize ±Inf and does not expect
-// EOF at the end.
-func (z *Float) scan(r io.ByteScanner, base int) (f *Float, b int, err error) {
-	prec := z.prec
-	if prec == 0 {
-		prec = 64
-	}
-
-	// A reasonable value in case of an error.
-	z.form = zero
-
-	// sign
-	z.neg, err = scanSign(r)
-	if err != nil {
-		return
-	}
-
-	// mantissa
-	var fcount int // fractional digit count; valid if <= 0
-	z.mant, b, fcount, err = z.mant.scan(r, base, true)
-	if err != nil {
-		return
-	}
-
-	// exponent
-	var exp int64
-	var ebase int
-	exp, ebase, err = scanExponent(r, true, base == 0)
-	if err != nil {
-		return
-	}
-
-	// special-case 0
-	if len(z.mant) == 0 {
-		z.prec = prec
-		z.acc = Exact
-		z.form = zero
-		f = z
-		return
-	}
-	// len(z.mant) > 0
-
-	// The mantissa may have a radix point (fcount <= 0) and there
-	// may be a nonzero exponent exp. The radix point amounts to a
-	// division by b**(-fcount). An exponent means multiplication by
-	// ebase**exp. Finally, mantissa normalization (shift left) requires
-	// a correcting multiplication by 2**(-shiftcount). Multiplications
-	// are commutative, so we can apply them in any order as long as there
-	// is no loss of precision. We only have powers of 2 and 10, and
-	// we split powers of 10 into the product of the same powers of
-	// 2 and 5. This reduces the size of the multiplication factor
-	// needed for base-10 exponents.
-
-	// normalize mantissa and determine initial exponent contributions
-	exp2 := int64(len(z.mant))*_W - fnorm(z.mant)
-	exp5 := int64(0)
-
-	// determine binary or decimal exponent contribution of radix point
-	if fcount < 0 {
-		// The mantissa has a radix point ddd.dddd; and
-		// -fcount is the number of digits to the right
-		// of '.'. Adjust relevant exponent accordingly.
-		d := int64(fcount)
-		switch b {
-		case 10:
-			exp5 = d
-			fallthrough // 10**e == 5**e * 2**e
-		case 2:
-			exp2 += d
-		case 8:
-			exp2 += d * 3 // octal digits are 3 bits each
-		case 16:
-			exp2 += d * 4 // hexadecimal digits are 4 bits each
-		default:
-			panic("unexpected mantissa base")
-		}
-		// fcount consumed - not needed anymore
-	}
-
-	// take actual exponent into account
-	switch ebase {
-	case 10:
-		exp5 += exp
-		fallthrough // see fallthrough above
-	case 2:
-		exp2 += exp
-	default:
-		panic("unexpected exponent base")
-	}
-	// exp consumed - not needed anymore
-
-	// apply 2**exp2
-	if MinExp <= exp2 && exp2 <= MaxExp {
-		z.prec = prec
-		z.form = finite
-		z.exp = int32(exp2)
-		f = z
-	} else {
-		err = fmt.Errorf("exponent overflow")
-		return
-	}
-
-	if exp5 == 0 {
-		// no decimal exponent contribution
-		z.round(0)
-		return
-	}
-	// exp5 != 0
-
-	// apply 5**exp5
-	p := new(Float).SetPrec(z.Prec() + 64) // use more bits for p -- TODO(gri) what is the right number?
-	if exp5 < 0 {
-		z.Quo(z, p.pow5(uint64(-exp5)))
-	} else {
-		z.Mul(z, p.pow5(uint64(exp5)))
-	}
-
-	return
-}
-
-// These powers of 5 fit into a uint64.
-//
-//	for p, q := uint64(0), uint64(1); p < q; p, q = q, q*5 {
-//		fmt.Println(q)
-//	}
-//
-var pow5tab = [...]uint64{
-	1,
-	5,
-	25,
-	125,
-	625,
-	3125,
-	15625,
-	78125,
-	390625,
-	1953125,
-	9765625,
-	48828125,
-	244140625,
-	1220703125,
-	6103515625,
-	30517578125,
-	152587890625,
-	762939453125,
-	3814697265625,
-	19073486328125,
-	95367431640625,
-	476837158203125,
-	2384185791015625,
-	11920928955078125,
-	59604644775390625,
-	298023223876953125,
-	1490116119384765625,
-	7450580596923828125,
-}
-
-// pow5 sets z to 5**n and returns z.
-// n must not be negative.
-func (z *Float) pow5(n uint64) *Float {
-	const m = uint64(len(pow5tab) - 1)
-	if n <= m {
-		return z.SetUint64(pow5tab[n])
-	}
-	// n > m
-
-	z.SetUint64(pow5tab[m])
-	n -= m
-
-	// use more bits for f than for z
-	// TODO(gri) what is the right number?
-	f := new(Float).SetPrec(z.Prec() + 64).SetUint64(5)
-
-	for n > 0 {
-		if n&1 != 0 {
-			z.Mul(z, f)
-		}
-		f.Mul(f, f)
-		n >>= 1
-	}
-
-	return z
-}
-
-// Parse parses s which must contain a text representation of a floating-
-// point number with a mantissa in the given conversion base (the exponent
-// is always a decimal number), or a string representing an infinite value.
-//
-// For base 0, an underscore character ``_'' may appear between a base
-// prefix and an adjacent digit, and between successive digits; such
-// underscores do not change the value of the number, or the returned
-// digit count. Incorrect placement of underscores is reported as an
-// error if there are no other errors. If base != 0, underscores are
-// not recognized and thus terminate scanning like any other character
-// that is not a valid radix point or digit.
-//
-// It sets z to the (possibly rounded) value of the corresponding floating-
-// point value, and returns z, the actual base b, and an error err, if any.
-// The entire string (not just a prefix) must be consumed for success.
-// If z's precision is 0, it is changed to 64 before rounding takes effect.
-// The number must be of the form:
-//
-//     number    = [ sign ] ( float | "inf" | "Inf" ) .
-//     sign      = "+" | "-" .
-//     float     = ( mantissa | prefix pmantissa ) [ exponent ] .
-//     prefix    = "0" [ "b" | "B" | "o" | "O" | "x" | "X" ] .
-//     mantissa  = digits "." [ digits ] | digits | "." digits .
-//     pmantissa = [ "_" ] digits "." [ digits ] | [ "_" ] digits | "." digits .
-//     exponent  = ( "e" | "E" | "p" | "P" ) [ sign ] digits .
-//     digits    = digit { [ "_" ] digit } .
-//     digit     = "0" ... "9" | "a" ... "z" | "A" ... "Z" .
-//
-// The base argument must be 0, 2, 8, 10, or 16. Providing an invalid base
-// argument will lead to a run-time panic.
-//
-// For base 0, the number prefix determines the actual base: A prefix of
-// ``0b'' or ``0B'' selects base 2, ``0o'' or ``0O'' selects base 8, and
-// ``0x'' or ``0X'' selects base 16. Otherwise, the actual base is 10 and
-// no prefix is accepted. The octal prefix "0" is not supported (a leading
-// "0" is simply considered a "0").
-//
-// A "p" or "P" exponent indicates a base 2 (rather then base 10) exponent;
-// for instance, "0x1.fffffffffffffp1023" (using base 0) represents the
-// maximum float64 value. For hexadecimal mantissae, the exponent character
-// must be one of 'p' or 'P', if present (an "e" or "E" exponent indicator
-// cannot be distinguished from a mantissa digit).
-//
-// The returned *Float f is nil and the value of z is valid but not
-// defined if an error is reported.
-//
-func (z *Float) Parse(s string, base int) (f *Float, b int, err error) {
-	// scan doesn't handle ±Inf
-	if len(s) == 3 && (s == "Inf" || s == "inf") {
-		f = z.SetInf(false)
-		return
-	}
-	if len(s) == 4 && (s[0] == '+' || s[0] == '-') && (s[1:] == "Inf" || s[1:] == "inf") {
-		f = z.SetInf(s[0] == '-')
-		return
-	}
-
-	r := strings.NewReader(s)
-	if f, b, err = z.scan(r, base); err != nil {
-		return
-	}
-
-	// entire string must have been consumed
-	if ch, err2 := r.ReadByte(); err2 == nil {
-		err = fmt.Errorf("expected end of string, found %q", ch)
-	} else if err2 != io.EOF {
-		err = err2
-	}
-
-	return
-}
-
-// ParseFloat is like f.Parse(s, base) with f set to the given precision
-// and rounding mode.
-func ParseFloat(s string, base int, prec uint, mode RoundingMode) (f *Float, b int, err error) {
-	return new(Float).SetPrec(prec).SetMode(mode).Parse(s, base)
-}
-
-var _ fmt.Scanner = (*Float)(nil) // *Float must implement fmt.Scanner
-
-// Scan is a support routine for fmt.Scanner; it sets z to the value of
-// the scanned number. It accepts formats whose verbs are supported by
-// fmt.Scan for floating point values, which are:
-// 'b' (binary), 'e', 'E', 'f', 'F', 'g' and 'G'.
-// Scan doesn't handle ±Inf.
-func (z *Float) Scan(s fmt.ScanState, ch rune) error {
-	s.SkipSpace()
-	_, _, err := z.scan(byteReader{s}, 0)
-	return err
-}
diff --git a/contrib/go/_std_1.18/src/math/big/floatmarsh.go b/contrib/go/_std_1.18/src/math/big/floatmarsh.go
deleted file mode 100644
index d1c1dab069..0000000000
--- a/contrib/go/_std_1.18/src/math/big/floatmarsh.go
+++ /dev/null
@@ -1,120 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file implements encoding/decoding of Floats.
-
-package big
-
-import (
-	"encoding/binary"
-	"fmt"
-)
-
-// Gob codec version. Permits backward-compatible changes to the encoding.
-const floatGobVersion byte = 1
-
-// GobEncode implements the gob.GobEncoder interface.
-// The Float value and all its attributes (precision,
-// rounding mode, accuracy) are marshaled.
-func (x *Float) GobEncode() ([]byte, error) {
-	if x == nil {
-		return nil, nil
-	}
-
-	// determine max. space (bytes) required for encoding
-	sz := 1 + 1 + 4 // version + mode|acc|form|neg (3+2+2+1bit) + prec
-	n := 0          // number of mantissa words
-	if x.form == finite {
-		// add space for mantissa and exponent
-		n = int((x.prec + (_W - 1)) / _W) // required mantissa length in words for given precision
-		// actual mantissa slice could be shorter (trailing 0's) or longer (unused bits):
-		// - if shorter, only encode the words present
-		// - if longer, cut off unused words when encoding in bytes
-		//   (in practice, this should never happen since rounding
-		//   takes care of it, but be safe and do it always)
-		if len(x.mant) < n {
-			n = len(x.mant)
-		}
-		// len(x.mant) >= n
-		sz += 4 + n*_S // exp + mant
-	}
-	buf := make([]byte, sz)
-
-	buf[0] = floatGobVersion
-	b := byte(x.mode&7)<<5 | byte((x.acc+1)&3)<<3 | byte(x.form&3)<<1
-	if x.neg {
-		b |= 1
-	}
-	buf[1] = b
-	binary.BigEndian.PutUint32(buf[2:], x.prec)
-
-	if x.form == finite {
-		binary.BigEndian.PutUint32(buf[6:], uint32(x.exp))
-		x.mant[len(x.mant)-n:].bytes(buf[10:]) // cut off unused trailing words
-	}
-
-	return buf, nil
-}
-
-// GobDecode implements the gob.GobDecoder interface.
-// The result is rounded per the precision and rounding mode of
-// z unless z's precision is 0, in which case z is set exactly
-// to the decoded value.
-func (z *Float) GobDecode(buf []byte) error {
-	if len(buf) == 0 {
-		// Other side sent a nil or default value.
-		*z = Float{}
-		return nil
-	}
-
-	if buf[0] != floatGobVersion {
-		return fmt.Errorf("Float.GobDecode: encoding version %d not supported", buf[0])
-	}
-
-	oldPrec := z.prec
-	oldMode := z.mode
-
-	b := buf[1]
-	z.mode = RoundingMode((b >> 5) & 7)
-	z.acc = Accuracy((b>>3)&3) - 1
-	z.form = form((b >> 1) & 3)
-	z.neg = b&1 != 0
-	z.prec = binary.BigEndian.Uint32(buf[2:])
-
-	if z.form == finite {
-		z.exp = int32(binary.BigEndian.Uint32(buf[6:]))
-		z.mant = z.mant.setBytes(buf[10:])
-	}
-
-	if oldPrec != 0 {
-		z.mode = oldMode
-		z.SetPrec(uint(oldPrec))
-	}
-
-	return nil
-}
-
-// MarshalText implements the encoding.TextMarshaler interface.
-// Only the Float value is marshaled (in full precision), other
-// attributes such as precision or accuracy are ignored.
-func (x *Float) MarshalText() (text []byte, err error) {
-	if x == nil {
-		return []byte("<nil>"), nil
-	}
-	var buf []byte
-	return x.Append(buf, 'g', -1), nil
-}
-
-// UnmarshalText implements the encoding.TextUnmarshaler interface.
-// The result is rounded per the precision and rounding mode of z.
-// If z's precision is 0, it is changed to 64 before rounding takes
-// effect.
-func (z *Float) UnmarshalText(text []byte) error {
-	// TODO(gri): get rid of the []byte/string conversion
-	_, _, err := z.Parse(string(text), 0)
-	if err != nil {
-		err = fmt.Errorf("math/big: cannot unmarshal %q into a *big.Float (%v)", text, err)
-	}
-	return err
-}
diff --git a/contrib/go/_std_1.18/src/math/big/int.go b/contrib/go/_std_1.18/src/math/big/int.go
deleted file mode 100644
index 7647346486..0000000000
--- a/contrib/go/_std_1.18/src/math/big/int.go
+++ /dev/null
@@ -1,1218 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file implements signed multi-precision integers.
-
-package big
-
-import (
-	"fmt"
-	"io"
-	"math/rand"
-	"strings"
-)
-
-// An Int represents a signed multi-precision integer.
-// The zero value for an Int represents the value 0.
-//
-// Operations always take pointer arguments (*Int) rather
-// than Int values, and each unique Int value requires
-// its own unique *Int pointer. To "copy" an Int value,
-// an existing (or newly allocated) Int must be set to
-// a new value using the Int.Set method; shallow copies
-// of Ints are not supported and may lead to errors.
-type Int struct {
-	neg bool // sign
-	abs nat  // absolute value of the integer
-}
-
-var intOne = &Int{false, natOne}
-
-// Sign returns:
-//
-//	-1 if x <  0
-//	 0 if x == 0
-//	+1 if x >  0
-//
-func (x *Int) Sign() int {
-	if len(x.abs) == 0 {
-		return 0
-	}
-	if x.neg {
-		return -1
-	}
-	return 1
-}
-
-// SetInt64 sets z to x and returns z.
-func (z *Int) SetInt64(x int64) *Int {
-	neg := false
-	if x < 0 {
-		neg = true
-		x = -x
-	}
-	z.abs = z.abs.setUint64(uint64(x))
-	z.neg = neg
-	return z
-}
-
-// SetUint64 sets z to x and returns z.
-func (z *Int) SetUint64(x uint64) *Int {
-	z.abs = z.abs.setUint64(x)
-	z.neg = false
-	return z
-}
-
-// NewInt allocates and returns a new Int set to x.
-func NewInt(x int64) *Int {
-	return new(Int).SetInt64(x)
-}
-
-// Set sets z to x and returns z.
-func (z *Int) Set(x *Int) *Int {
-	if z != x {
-		z.abs = z.abs.set(x.abs)
-		z.neg = x.neg
-	}
-	return z
-}
-
-// Bits provides raw (unchecked but fast) access to x by returning its
-// absolute value as a little-endian Word slice. The result and x share
-// the same underlying array.
-// Bits is intended to support implementation of missing low-level Int
-// functionality outside this package; it should be avoided otherwise.
-func (x *Int) Bits() []Word {
-	return x.abs
-}
-
-// SetBits provides raw (unchecked but fast) access to z by setting its
-// value to abs, interpreted as a little-endian Word slice, and returning
-// z. The result and abs share the same underlying array.
-// SetBits is intended to support implementation of missing low-level Int
-// functionality outside this package; it should be avoided otherwise.
-func (z *Int) SetBits(abs []Word) *Int {
-	z.abs = nat(abs).norm()
-	z.neg = false
-	return z
-}
-
-// Abs sets z to |x| (the absolute value of x) and returns z.
-func (z *Int) Abs(x *Int) *Int {
-	z.Set(x)
-	z.neg = false
-	return z
-}
-
-// Neg sets z to -x and returns z.
-func (z *Int) Neg(x *Int) *Int {
-	z.Set(x)
-	z.neg = len(z.abs) > 0 && !z.neg // 0 has no sign
-	return z
-}
-
-// Add sets z to the sum x+y and returns z.
-func (z *Int) Add(x, y *Int) *Int {
-	neg := x.neg
-	if x.neg == y.neg {
-		// x + y == x + y
-		// (-x) + (-y) == -(x + y)
-		z.abs = z.abs.add(x.abs, y.abs)
-	} else {
-		// x + (-y) == x - y == -(y - x)
-		// (-x) + y == y - x == -(x - y)
-		if x.abs.cmp(y.abs) >= 0 {
-			z.abs = z.abs.sub(x.abs, y.abs)
-		} else {
-			neg = !neg
-			z.abs = z.abs.sub(y.abs, x.abs)
-		}
-	}
-	z.neg = len(z.abs) > 0 && neg // 0 has no sign
-	return z
-}
-
-// Sub sets z to the difference x-y and returns z.
-func (z *Int) Sub(x, y *Int) *Int {
-	neg := x.neg
-	if x.neg != y.neg {
-		// x - (-y) == x + y
-		// (-x) - y == -(x + y)
-		z.abs = z.abs.add(x.abs, y.abs)
-	} else {
-		// x - y == x - y == -(y - x)
-		// (-x) - (-y) == y - x == -(x - y)
-		if x.abs.cmp(y.abs) >= 0 {
-			z.abs = z.abs.sub(x.abs, y.abs)
-		} else {
-			neg = !neg
-			z.abs = z.abs.sub(y.abs, x.abs)
-		}
-	}
-	z.neg = len(z.abs) > 0 && neg // 0 has no sign
-	return z
-}
-
-// Mul sets z to the product x*y and returns z.
-func (z *Int) Mul(x, y *Int) *Int {
-	// x * y == x * y
-	// x * (-y) == -(x * y)
-	// (-x) * y == -(x * y)
-	// (-x) * (-y) == x * y
-	if x == y {
-		z.abs = z.abs.sqr(x.abs)
-		z.neg = false
-		return z
-	}
-	z.abs = z.abs.mul(x.abs, y.abs)
-	z.neg = len(z.abs) > 0 && x.neg != y.neg // 0 has no sign
-	return z
-}
-
-// MulRange sets z to the product of all integers
-// in the range [a, b] inclusively and returns z.
-// If a > b (empty range), the result is 1.
-func (z *Int) MulRange(a, b int64) *Int {
-	switch {
-	case a > b:
-		return z.SetInt64(1) // empty range
-	case a <= 0 && b >= 0:
-		return z.SetInt64(0) // range includes 0
-	}
-	// a <= b && (b < 0 || a > 0)
-
-	neg := false
-	if a < 0 {
-		neg = (b-a)&1 == 0
-		a, b = -b, -a
-	}
-
-	z.abs = z.abs.mulRange(uint64(a), uint64(b))
-	z.neg = neg
-	return z
-}
-
-// Binomial sets z to the binomial coefficient of (n, k) and returns z.
-func (z *Int) Binomial(n, k int64) *Int {
-	// reduce the number of multiplications by reducing k
-	if n/2 < k && k <= n {
-		k = n - k // Binomial(n, k) == Binomial(n, n-k)
-	}
-	var a, b Int
-	a.MulRange(n-k+1, n)
-	b.MulRange(1, k)
-	return z.Quo(&a, &b)
-}
-
-// Quo sets z to the quotient x/y for y != 0 and returns z.
-// If y == 0, a division-by-zero run-time panic occurs.
-// Quo implements truncated division (like Go); see QuoRem for more details.
-func (z *Int) Quo(x, y *Int) *Int {
-	z.abs, _ = z.abs.div(nil, x.abs, y.abs)
-	z.neg = len(z.abs) > 0 && x.neg != y.neg // 0 has no sign
-	return z
-}
-
-// Rem sets z to the remainder x%y for y != 0 and returns z.
-// If y == 0, a division-by-zero run-time panic occurs.
-// Rem implements truncated modulus (like Go); see QuoRem for more details.
-func (z *Int) Rem(x, y *Int) *Int {
-	_, z.abs = nat(nil).div(z.abs, x.abs, y.abs)
-	z.neg = len(z.abs) > 0 && x.neg // 0 has no sign
-	return z
-}
-
-// QuoRem sets z to the quotient x/y and r to the remainder x%y
-// and returns the pair (z, r) for y != 0.
-// If y == 0, a division-by-zero run-time panic occurs.
-//
-// QuoRem implements T-division and modulus (like Go):
-//
-//	q = x/y      with the result truncated to zero
-//	r = x - y*q
-//
-// (See Daan Leijen, ``Division and Modulus for Computer Scientists''.)
-// See DivMod for Euclidean division and modulus (unlike Go).
-//
-func (z *Int) QuoRem(x, y, r *Int) (*Int, *Int) {
-	z.abs, r.abs = z.abs.div(r.abs, x.abs, y.abs)
-	z.neg, r.neg = len(z.abs) > 0 && x.neg != y.neg, len(r.abs) > 0 && x.neg // 0 has no sign
-	return z, r
-}
-
-// Div sets z to the quotient x/y for y != 0 and returns z.
-// If y == 0, a division-by-zero run-time panic occurs.
-// Div implements Euclidean division (unlike Go); see DivMod for more details.
-func (z *Int) Div(x, y *Int) *Int {
-	y_neg := y.neg // z may be an alias for y
-	var r Int
-	z.QuoRem(x, y, &r)
-	if r.neg {
-		if y_neg {
-			z.Add(z, intOne)
-		} else {
-			z.Sub(z, intOne)
-		}
-	}
-	return z
-}
-
-// Mod sets z to the modulus x%y for y != 0 and returns z.
-// If y == 0, a division-by-zero run-time panic occurs.
-// Mod implements Euclidean modulus (unlike Go); see DivMod for more details.
-func (z *Int) Mod(x, y *Int) *Int {
-	y0 := y // save y
-	if z == y || alias(z.abs, y.abs) {
-		y0 = new(Int).Set(y)
-	}
-	var q Int
-	q.QuoRem(x, y, z)
-	if z.neg {
-		if y0.neg {
-			z.Sub(z, y0)
-		} else {
-			z.Add(z, y0)
-		}
-	}
-	return z
-}
-
-// DivMod sets z to the quotient x div y and m to the modulus x mod y
-// and returns the pair (z, m) for y != 0.
-// If y == 0, a division-by-zero run-time panic occurs.
-//
-// DivMod implements Euclidean division and modulus (unlike Go):
-//
-//	q = x div y  such that
-//	m = x - y*q  with 0 <= m < |y|
-//
-// (See Raymond T. Boute, ``The Euclidean definition of the functions
-// div and mod''. ACM Transactions on Programming Languages and
-// Systems (TOPLAS), 14(2):127-144, New York, NY, USA, 4/1992.
-// ACM press.)
-// See QuoRem for T-division and modulus (like Go).
-//
-func (z *Int) DivMod(x, y, m *Int) (*Int, *Int) {
-	y0 := y // save y
-	if z == y || alias(z.abs, y.abs) {
-		y0 = new(Int).Set(y)
-	}
-	z.QuoRem(x, y, m)
-	if m.neg {
-		if y0.neg {
-			z.Add(z, intOne)
-			m.Sub(m, y0)
-		} else {
-			z.Sub(z, intOne)
-			m.Add(m, y0)
-		}
-	}
-	return z, m
-}
-
-// Cmp compares x and y and returns:
-//
-//   -1 if x <  y
-//    0 if x == y
-//   +1 if x >  y
-//
-func (x *Int) Cmp(y *Int) (r int) {
-	// x cmp y == x cmp y
-	// x cmp (-y) == x
-	// (-x) cmp y == y
-	// (-x) cmp (-y) == -(x cmp y)
-	switch {
-	case x == y:
-		// nothing to do
-	case x.neg == y.neg:
-		r = x.abs.cmp(y.abs)
-		if x.neg {
-			r = -r
-		}
-	case x.neg:
-		r = -1
-	default:
-		r = 1
-	}
-	return
-}
-
-// CmpAbs compares the absolute values of x and y and returns:
-//
-//   -1 if |x| <  |y|
-//    0 if |x| == |y|
-//   +1 if |x| >  |y|
-//
-func (x *Int) CmpAbs(y *Int) int {
-	return x.abs.cmp(y.abs)
-}
-
-// low32 returns the least significant 32 bits of x.
-func low32(x nat) uint32 {
-	if len(x) == 0 {
-		return 0
-	}
-	return uint32(x[0])
-}
-
-// low64 returns the least significant 64 bits of x.
-func low64(x nat) uint64 {
-	if len(x) == 0 {
-		return 0
-	}
-	v := uint64(x[0])
-	if _W == 32 && len(x) > 1 {
-		return uint64(x[1])<<32 | v
-	}
-	return v
-}
-
-// Int64 returns the int64 representation of x.
-// If x cannot be represented in an int64, the result is undefined.
-func (x *Int) Int64() int64 {
-	v := int64(low64(x.abs))
-	if x.neg {
-		v = -v
-	}
-	return v
-}
-
-// Uint64 returns the uint64 representation of x.
-// If x cannot be represented in a uint64, the result is undefined.
-func (x *Int) Uint64() uint64 {
-	return low64(x.abs)
-}
-
-// IsInt64 reports whether x can be represented as an int64.
-func (x *Int) IsInt64() bool {
-	if len(x.abs) <= 64/_W {
-		w := int64(low64(x.abs))
-		return w >= 0 || x.neg && w == -w
-	}
-	return false
-}
-
-// IsUint64 reports whether x can be represented as a uint64.
-func (x *Int) IsUint64() bool {
-	return !x.neg && len(x.abs) <= 64/_W
-}
-
-// SetString sets z to the value of s, interpreted in the given base,
-// and returns z and a boolean indicating success. The entire string
-// (not just a prefix) must be valid for success. If SetString fails,
-// the value of z is undefined but the returned value is nil.
-//
-// The base argument must be 0 or a value between 2 and MaxBase.
-// For base 0, the number prefix determines the actual base: A prefix of
-// ``0b'' or ``0B'' selects base 2, ``0'', ``0o'' or ``0O'' selects base 8,
-// and ``0x'' or ``0X'' selects base 16. Otherwise, the selected base is 10
-// and no prefix is accepted.
-//
-// For bases <= 36, lower and upper case letters are considered the same:
-// The letters 'a' to 'z' and 'A' to 'Z' represent digit values 10 to 35.
-// For bases > 36, the upper case letters 'A' to 'Z' represent the digit
-// values 36 to 61.
-//
-// For base 0, an underscore character ``_'' may appear between a base
-// prefix and an adjacent digit, and between successive digits; such
-// underscores do not change the value of the number.
-// Incorrect placement of underscores is reported as an error if there
-// are no other errors. If base != 0, underscores are not recognized
-// and act like any other character that is not a valid digit.
-//
-func (z *Int) SetString(s string, base int) (*Int, bool) {
-	return z.setFromScanner(strings.NewReader(s), base)
-}
-
-// setFromScanner implements SetString given an io.ByteScanner.
-// For documentation see comments of SetString.
-func (z *Int) setFromScanner(r io.ByteScanner, base int) (*Int, bool) {
-	if _, _, err := z.scan(r, base); err != nil {
-		return nil, false
-	}
-	// entire content must have been consumed
-	if _, err := r.ReadByte(); err != io.EOF {
-		return nil, false
-	}
-	return z, true // err == io.EOF => scan consumed all content of r
-}
-
-// SetBytes interprets buf as the bytes of a big-endian unsigned
-// integer, sets z to that value, and returns z.
-func (z *Int) SetBytes(buf []byte) *Int {
-	z.abs = z.abs.setBytes(buf)
-	z.neg = false
-	return z
-}
-
-// Bytes returns the absolute value of x as a big-endian byte slice.
-//
-// To use a fixed length slice, or a preallocated one, use FillBytes.
-func (x *Int) Bytes() []byte {
-	buf := make([]byte, len(x.abs)*_S)
-	return buf[x.abs.bytes(buf):]
-}
-
-// FillBytes sets buf to the absolute value of x, storing it as a zero-extended
-// big-endian byte slice, and returns buf.
-//
-// If the absolute value of x doesn't fit in buf, FillBytes will panic.
-func (x *Int) FillBytes(buf []byte) []byte {
-	// Clear whole buffer. (This gets optimized into a memclr.)
-	for i := range buf {
-		buf[i] = 0
-	}
-	x.abs.bytes(buf)
-	return buf
-}
-
-// BitLen returns the length of the absolute value of x in bits.
-// The bit length of 0 is 0.
-func (x *Int) BitLen() int {
-	return x.abs.bitLen()
-}
-
-// TrailingZeroBits returns the number of consecutive least significant zero
-// bits of |x|.
-func (x *Int) TrailingZeroBits() uint {
-	return x.abs.trailingZeroBits()
-}
-
-// Exp sets z = x**y mod |m| (i.e. the sign of m is ignored), and returns z.
-// If m == nil or m == 0, z = x**y unless y <= 0 then z = 1. If m != 0, y < 0,
-// and x and m are not relatively prime, z is unchanged and nil is returned.
-//
-// Modular exponentiation of inputs of a particular size is not a
-// cryptographically constant-time operation.
-func (z *Int) Exp(x, y, m *Int) *Int {
-	// See Knuth, volume 2, section 4.6.3.
-	xWords := x.abs
-	if y.neg {
-		if m == nil || len(m.abs) == 0 {
-			return z.SetInt64(1)
-		}
-		// for y < 0: x**y mod m == (x**(-1))**|y| mod m
-		inverse := new(Int).ModInverse(x, m)
-		if inverse == nil {
-			return nil
-		}
-		xWords = inverse.abs
-	}
-	yWords := y.abs
-
-	var mWords nat
-	if m != nil {
-		mWords = m.abs // m.abs may be nil for m == 0
-	}
-
-	z.abs = z.abs.expNN(xWords, yWords, mWords)
-	z.neg = len(z.abs) > 0 && x.neg && len(yWords) > 0 && yWords[0]&1 == 1 // 0 has no sign
-	if z.neg && len(mWords) > 0 {
-		// make modulus result positive
-		z.abs = z.abs.sub(mWords, z.abs) // z == x**y mod |m| && 0 <= z < |m|
-		z.neg = false
-	}
-
-	return z
-}
-
-// GCD sets z to the greatest common divisor of a and b and returns z.
-// If x or y are not nil, GCD sets their value such that z = a*x + b*y.
-//
-// a and b may be positive, zero or negative. (Before Go 1.14 both had
-// to be > 0.) Regardless of the signs of a and b, z is always >= 0.
-//
-// If a == b == 0, GCD sets z = x = y = 0.
-//
-// If a == 0 and b != 0, GCD sets z = |b|, x = 0, y = sign(b) * 1.
-//
-// If a != 0 and b == 0, GCD sets z = |a|, x = sign(a) * 1, y = 0.
-func (z *Int) GCD(x, y, a, b *Int) *Int {
-	if len(a.abs) == 0 || len(b.abs) == 0 {
-		lenA, lenB, negA, negB := len(a.abs), len(b.abs), a.neg, b.neg
-		if lenA == 0 {
-			z.Set(b)
-		} else {
-			z.Set(a)
-		}
-		z.neg = false
-		if x != nil {
-			if lenA == 0 {
-				x.SetUint64(0)
-			} else {
-				x.SetUint64(1)
-				x.neg = negA
-			}
-		}
-		if y != nil {
-			if lenB == 0 {
-				y.SetUint64(0)
-			} else {
-				y.SetUint64(1)
-				y.neg = negB
-			}
-		}
-		return z
-	}
-
-	return z.lehmerGCD(x, y, a, b)
-}
-
-// lehmerSimulate attempts to simulate several Euclidean update steps
-// using the leading digits of A and B.  It returns u0, u1, v0, v1
-// such that A and B can be updated as:
-//		A = u0*A + v0*B
-//		B = u1*A + v1*B
-// Requirements: A >= B and len(B.abs) >= 2
-// Since we are calculating with full words to avoid overflow,
-// we use 'even' to track the sign of the cosequences.
-// For even iterations: u0, v1 >= 0 && u1, v0 <= 0
-// For odd  iterations: u0, v1 <= 0 && u1, v0 >= 0
-func lehmerSimulate(A, B *Int) (u0, u1, v0, v1 Word, even bool) {
-	// initialize the digits
-	var a1, a2, u2, v2 Word
-
-	m := len(B.abs) // m >= 2
-	n := len(A.abs) // n >= m >= 2
-
-	// extract the top Word of bits from A and B
-	h := nlz(A.abs[n-1])
-	a1 = A.abs[n-1]<<h | A.abs[n-2]>>(_W-h)
-	// B may have implicit zero words in the high bits if the lengths differ
-	switch {
-	case n == m:
-		a2 = B.abs[n-1]<<h | B.abs[n-2]>>(_W-h)
-	case n == m+1:
-		a2 = B.abs[n-2] >> (_W - h)
-	default:
-		a2 = 0
-	}
-
-	// Since we are calculating with full words to avoid overflow,
-	// we use 'even' to track the sign of the cosequences.
-	// For even iterations: u0, v1 >= 0 && u1, v0 <= 0
-	// For odd  iterations: u0, v1 <= 0 && u1, v0 >= 0
-	// The first iteration starts with k=1 (odd).
-	even = false
-	// variables to track the cosequences
-	u0, u1, u2 = 0, 1, 0
-	v0, v1, v2 = 0, 0, 1
-
-	// Calculate the quotient and cosequences using Collins' stopping condition.
-	// Note that overflow of a Word is not possible when computing the remainder
-	// sequence and cosequences since the cosequence size is bounded by the input size.
-	// See section 4.2 of Jebelean for details.
-	for a2 >= v2 && a1-a2 >= v1+v2 {
-		q, r := a1/a2, a1%a2
-		a1, a2 = a2, r
-		u0, u1, u2 = u1, u2, u1+q*u2
-		v0, v1, v2 = v1, v2, v1+q*v2
-		even = !even
-	}
-	return
-}
-
-// lehmerUpdate updates the inputs A and B such that:
-//		A = u0*A + v0*B
-//		B = u1*A + v1*B
-// where the signs of u0, u1, v0, v1 are given by even
-// For even == true: u0, v1 >= 0 && u1, v0 <= 0
-// For even == false: u0, v1 <= 0 && u1, v0 >= 0
-// q, r, s, t are temporary variables to avoid allocations in the multiplication
-func lehmerUpdate(A, B, q, r, s, t *Int, u0, u1, v0, v1 Word, even bool) {
-
-	t.abs = t.abs.setWord(u0)
-	s.abs = s.abs.setWord(v0)
-	t.neg = !even
-	s.neg = even
-
-	t.Mul(A, t)
-	s.Mul(B, s)
-
-	r.abs = r.abs.setWord(u1)
-	q.abs = q.abs.setWord(v1)
-	r.neg = even
-	q.neg = !even
-
-	r.Mul(A, r)
-	q.Mul(B, q)
-
-	A.Add(t, s)
-	B.Add(r, q)
-}
-
-// euclidUpdate performs a single step of the Euclidean GCD algorithm
-// if extended is true, it also updates the cosequence Ua, Ub
-func euclidUpdate(A, B, Ua, Ub, q, r, s, t *Int, extended bool) {
-	q, r = q.QuoRem(A, B, r)
-
-	*A, *B, *r = *B, *r, *A
-
-	if extended {
-		// Ua, Ub = Ub, Ua - q*Ub
-		t.Set(Ub)
-		s.Mul(Ub, q)
-		Ub.Sub(Ua, s)
-		Ua.Set(t)
-	}
-}
-
-// lehmerGCD sets z to the greatest common divisor of a and b,
-// which both must be != 0, and returns z.
-// If x or y are not nil, their values are set such that z = a*x + b*y.
-// See Knuth, The Art of Computer Programming, Vol. 2, Section 4.5.2, Algorithm L.
-// This implementation uses the improved condition by Collins requiring only one
-// quotient and avoiding the possibility of single Word overflow.
-// See Jebelean, "Improving the multiprecision Euclidean algorithm",
-// Design and Implementation of Symbolic Computation Systems, pp 45-58.
-// The cosequences are updated according to Algorithm 10.45 from
-// Cohen et al. "Handbook of Elliptic and Hyperelliptic Curve Cryptography" pp 192.
-func (z *Int) lehmerGCD(x, y, a, b *Int) *Int {
-	var A, B, Ua, Ub *Int
-
-	A = new(Int).Abs(a)
-	B = new(Int).Abs(b)
-
-	extended := x != nil || y != nil
-
-	if extended {
-		// Ua (Ub) tracks how many times input a has been accumulated into A (B).
-		Ua = new(Int).SetInt64(1)
-		Ub = new(Int)
-	}
-
-	// temp variables for multiprecision update
-	q := new(Int)
-	r := new(Int)
-	s := new(Int)
-	t := new(Int)
-
-	// ensure A >= B
-	if A.abs.cmp(B.abs) < 0 {
-		A, B = B, A
-		Ub, Ua = Ua, Ub
-	}
-
-	// loop invariant A >= B
-	for len(B.abs) > 1 {
-		// Attempt to calculate in single-precision using leading words of A and B.
-		u0, u1, v0, v1, even := lehmerSimulate(A, B)
-
-		// multiprecision Step
-		if v0 != 0 {
-			// Simulate the effect of the single-precision steps using the cosequences.
-			// A = u0*A + v0*B
-			// B = u1*A + v1*B
-			lehmerUpdate(A, B, q, r, s, t, u0, u1, v0, v1, even)
-
-			if extended {
-				// Ua = u0*Ua + v0*Ub
-				// Ub = u1*Ua + v1*Ub
-				lehmerUpdate(Ua, Ub, q, r, s, t, u0, u1, v0, v1, even)
-			}
-
-		} else {
-			// Single-digit calculations failed to simulate any quotients.
-			// Do a standard Euclidean step.
-			euclidUpdate(A, B, Ua, Ub, q, r, s, t, extended)
-		}
-	}
-
-	if len(B.abs) > 0 {
-		// extended Euclidean algorithm base case if B is a single Word
-		if len(A.abs) > 1 {
-			// A is longer than a single Word, so one update is needed.
-			euclidUpdate(A, B, Ua, Ub, q, r, s, t, extended)
-		}
-		if len(B.abs) > 0 {
-			// A and B are both a single Word.
-			aWord, bWord := A.abs[0], B.abs[0]
-			if extended {
-				var ua, ub, va, vb Word
-				ua, ub = 1, 0
-				va, vb = 0, 1
-				even := true
-				for bWord != 0 {
-					q, r := aWord/bWord, aWord%bWord
-					aWord, bWord = bWord, r
-					ua, ub = ub, ua+q*ub
-					va, vb = vb, va+q*vb
-					even = !even
-				}
-
-				t.abs = t.abs.setWord(ua)
-				s.abs = s.abs.setWord(va)
-				t.neg = !even
-				s.neg = even
-
-				t.Mul(Ua, t)
-				s.Mul(Ub, s)
-
-				Ua.Add(t, s)
-			} else {
-				for bWord != 0 {
-					aWord, bWord = bWord, aWord%bWord
-				}
-			}
-			A.abs[0] = aWord
-		}
-	}
-	negA := a.neg
-	if y != nil {
-		// avoid aliasing b needed in the division below
-		if y == b {
-			B.Set(b)
-		} else {
-			B = b
-		}
-		// y = (z - a*x)/b
-		y.Mul(a, Ua) // y can safely alias a
-		if negA {
-			y.neg = !y.neg
-		}
-		y.Sub(A, y)
-		y.Div(y, B)
-	}
-
-	if x != nil {
-		*x = *Ua
-		if negA {
-			x.neg = !x.neg
-		}
-	}
-
-	*z = *A
-
-	return z
-}
-
-// Rand sets z to a pseudo-random number in [0, n) and returns z.
-//
-// As this uses the math/rand package, it must not be used for
-// security-sensitive work. Use crypto/rand.Int instead.
-func (z *Int) Rand(rnd *rand.Rand, n *Int) *Int {
-	z.neg = false
-	if n.neg || len(n.abs) == 0 {
-		z.abs = nil
-		return z
-	}
-	z.abs = z.abs.random(rnd, n.abs, n.abs.bitLen())
-	return z
-}
-
-// ModInverse sets z to the multiplicative inverse of g in the ring ℤ/nℤ
-// and returns z. If g and n are not relatively prime, g has no multiplicative
-// inverse in the ring ℤ/nℤ.  In this case, z is unchanged and the return value
-// is nil.
-func (z *Int) ModInverse(g, n *Int) *Int {
-	// GCD expects parameters a and b to be > 0.
-	if n.neg {
-		var n2 Int
-		n = n2.Neg(n)
-	}
-	if g.neg {
-		var g2 Int
-		g = g2.Mod(g, n)
-	}
-	var d, x Int
-	d.GCD(&x, nil, g, n)
-
-	// if and only if d==1, g and n are relatively prime
-	if d.Cmp(intOne) != 0 {
-		return nil
-	}
-
-	// x and y are such that g*x + n*y = 1, therefore x is the inverse element,
-	// but it may be negative, so convert to the range 0 <= z < |n|
-	if x.neg {
-		z.Add(&x, n)
-	} else {
-		z.Set(&x)
-	}
-	return z
-}
-
-// Jacobi returns the Jacobi symbol (x/y), either +1, -1, or 0.
-// The y argument must be an odd integer.
-func Jacobi(x, y *Int) int {
-	if len(y.abs) == 0 || y.abs[0]&1 == 0 {
-		panic(fmt.Sprintf("big: invalid 2nd argument to Int.Jacobi: need odd integer but got %s", y))
-	}
-
-	// We use the formulation described in chapter 2, section 2.4,
-	// "The Yacas Book of Algorithms":
-	// http://yacas.sourceforge.net/Algo.book.pdf
-
-	var a, b, c Int
-	a.Set(x)
-	b.Set(y)
-	j := 1
-
-	if b.neg {
-		if a.neg {
-			j = -1
-		}
-		b.neg = false
-	}
-
-	for {
-		if b.Cmp(intOne) == 0 {
-			return j
-		}
-		if len(a.abs) == 0 {
-			return 0
-		}
-		a.Mod(&a, &b)
-		if len(a.abs) == 0 {
-			return 0
-		}
-		// a > 0
-
-		// handle factors of 2 in 'a'
-		s := a.abs.trailingZeroBits()
-		if s&1 != 0 {
-			bmod8 := b.abs[0] & 7
-			if bmod8 == 3 || bmod8 == 5 {
-				j = -j
-			}
-		}
-		c.Rsh(&a, s) // a = 2^s*c
-
-		// swap numerator and denominator
-		if b.abs[0]&3 == 3 && c.abs[0]&3 == 3 {
-			j = -j
-		}
-		a.Set(&b)
-		b.Set(&c)
-	}
-}
-
-// modSqrt3Mod4 uses the identity
-//      (a^((p+1)/4))^2  mod p
-//   == u^(p+1)          mod p
-//   == u^2              mod p
-// to calculate the square root of any quadratic residue mod p quickly for 3
-// mod 4 primes.
-func (z *Int) modSqrt3Mod4Prime(x, p *Int) *Int {
-	e := new(Int).Add(p, intOne) // e = p + 1
-	e.Rsh(e, 2)                  // e = (p + 1) / 4
-	z.Exp(x, e, p)               // z = x^e mod p
-	return z
-}
-
-// modSqrt5Mod8 uses Atkin's observation that 2 is not a square mod p
-//   alpha ==  (2*a)^((p-5)/8)    mod p
-//   beta  ==  2*a*alpha^2        mod p  is a square root of -1
-//   b     ==  a*alpha*(beta-1)   mod p  is a square root of a
-// to calculate the square root of any quadratic residue mod p quickly for 5
-// mod 8 primes.
-func (z *Int) modSqrt5Mod8Prime(x, p *Int) *Int {
-	// p == 5 mod 8 implies p = e*8 + 5
-	// e is the quotient and 5 the remainder on division by 8
-	e := new(Int).Rsh(p, 3)  // e = (p - 5) / 8
-	tx := new(Int).Lsh(x, 1) // tx = 2*x
-	alpha := new(Int).Exp(tx, e, p)
-	beta := new(Int).Mul(alpha, alpha)
-	beta.Mod(beta, p)
-	beta.Mul(beta, tx)
-	beta.Mod(beta, p)
-	beta.Sub(beta, intOne)
-	beta.Mul(beta, x)
-	beta.Mod(beta, p)
-	beta.Mul(beta, alpha)
-	z.Mod(beta, p)
-	return z
-}
-
-// modSqrtTonelliShanks uses the Tonelli-Shanks algorithm to find the square
-// root of a quadratic residue modulo any prime.
-func (z *Int) modSqrtTonelliShanks(x, p *Int) *Int {
-	// Break p-1 into s*2^e such that s is odd.
-	var s Int
-	s.Sub(p, intOne)
-	e := s.abs.trailingZeroBits()
-	s.Rsh(&s, e)
-
-	// find some non-square n
-	var n Int
-	n.SetInt64(2)
-	for Jacobi(&n, p) != -1 {
-		n.Add(&n, intOne)
-	}
-
-	// Core of the Tonelli-Shanks algorithm. Follows the description in
-	// section 6 of "Square roots from 1; 24, 51, 10 to Dan Shanks" by Ezra
-	// Brown:
-	// https://www.maa.org/sites/default/files/pdf/upload_library/22/Polya/07468342.di020786.02p0470a.pdf
-	var y, b, g, t Int
-	y.Add(&s, intOne)
-	y.Rsh(&y, 1)
-	y.Exp(x, &y, p)  // y = x^((s+1)/2)
-	b.Exp(x, &s, p)  // b = x^s
-	g.Exp(&n, &s, p) // g = n^s
-	r := e
-	for {
-		// find the least m such that ord_p(b) = 2^m
-		var m uint
-		t.Set(&b)
-		for t.Cmp(intOne) != 0 {
-			t.Mul(&t, &t).Mod(&t, p)
-			m++
-		}
-
-		if m == 0 {
-			return z.Set(&y)
-		}
-
-		t.SetInt64(0).SetBit(&t, int(r-m-1), 1).Exp(&g, &t, p)
-		// t = g^(2^(r-m-1)) mod p
-		g.Mul(&t, &t).Mod(&g, p) // g = g^(2^(r-m)) mod p
-		y.Mul(&y, &t).Mod(&y, p)
-		b.Mul(&b, &g).Mod(&b, p)
-		r = m
-	}
-}
-
-// ModSqrt sets z to a square root of x mod p if such a square root exists, and
-// returns z. The modulus p must be an odd prime. If x is not a square mod p,
-// ModSqrt leaves z unchanged and returns nil. This function panics if p is
-// not an odd integer.
-func (z *Int) ModSqrt(x, p *Int) *Int {
-	switch Jacobi(x, p) {
-	case -1:
-		return nil // x is not a square mod p
-	case 0:
-		return z.SetInt64(0) // sqrt(0) mod p = 0
-	case 1:
-		break
-	}
-	if x.neg || x.Cmp(p) >= 0 { // ensure 0 <= x < p
-		x = new(Int).Mod(x, p)
-	}
-
-	switch {
-	case p.abs[0]%4 == 3:
-		// Check whether p is 3 mod 4, and if so, use the faster algorithm.
-		return z.modSqrt3Mod4Prime(x, p)
-	case p.abs[0]%8 == 5:
-		// Check whether p is 5 mod 8, use Atkin's algorithm.
-		return z.modSqrt5Mod8Prime(x, p)
-	default:
-		// Otherwise, use Tonelli-Shanks.
-		return z.modSqrtTonelliShanks(x, p)
-	}
-}
-
-// Lsh sets z = x << n and returns z.
-func (z *Int) Lsh(x *Int, n uint) *Int {
-	z.abs = z.abs.shl(x.abs, n)
-	z.neg = x.neg
-	return z
-}
-
-// Rsh sets z = x >> n and returns z.
-func (z *Int) Rsh(x *Int, n uint) *Int {
-	if x.neg {
-		// (-x) >> s == ^(x-1) >> s == ^((x-1) >> s) == -(((x-1) >> s) + 1)
-		t := z.abs.sub(x.abs, natOne) // no underflow because |x| > 0
-		t = t.shr(t, n)
-		z.abs = t.add(t, natOne)
-		z.neg = true // z cannot be zero if x is negative
-		return z
-	}
-
-	z.abs = z.abs.shr(x.abs, n)
-	z.neg = false
-	return z
-}
-
-// Bit returns the value of the i'th bit of x. That is, it
-// returns (x>>i)&1. The bit index i must be >= 0.
-func (x *Int) Bit(i int) uint {
-	if i == 0 {
-		// optimization for common case: odd/even test of x
-		if len(x.abs) > 0 {
-			return uint(x.abs[0] & 1) // bit 0 is same for -x
-		}
-		return 0
-	}
-	if i < 0 {
-		panic("negative bit index")
-	}
-	if x.neg {
-		t := nat(nil).sub(x.abs, natOne)
-		return t.bit(uint(i)) ^ 1
-	}
-
-	return x.abs.bit(uint(i))
-}
-
-// SetBit sets z to x, with x's i'th bit set to b (0 or 1).
-// That is, if b is 1 SetBit sets z = x | (1 << i);
-// if b is 0 SetBit sets z = x &^ (1 << i). If b is not 0 or 1,
-// SetBit will panic.
-func (z *Int) SetBit(x *Int, i int, b uint) *Int {
-	if i < 0 {
-		panic("negative bit index")
-	}
-	if x.neg {
-		t := z.abs.sub(x.abs, natOne)
-		t = t.setBit(t, uint(i), b^1)
-		z.abs = t.add(t, natOne)
-		z.neg = len(z.abs) > 0
-		return z
-	}
-	z.abs = z.abs.setBit(x.abs, uint(i), b)
-	z.neg = false
-	return z
-}
-
-// And sets z = x & y and returns z.
-func (z *Int) And(x, y *Int) *Int {
-	if x.neg == y.neg {
-		if x.neg {
-			// (-x) & (-y) == ^(x-1) & ^(y-1) == ^((x-1) | (y-1)) == -(((x-1) | (y-1)) + 1)
-			x1 := nat(nil).sub(x.abs, natOne)
-			y1 := nat(nil).sub(y.abs, natOne)
-			z.abs = z.abs.add(z.abs.or(x1, y1), natOne)
-			z.neg = true // z cannot be zero if x and y are negative
-			return z
-		}
-
-		// x & y == x & y
-		z.abs = z.abs.and(x.abs, y.abs)
-		z.neg = false
-		return z
-	}
-
-	// x.neg != y.neg
-	if x.neg {
-		x, y = y, x // & is symmetric
-	}
-
-	// x & (-y) == x & ^(y-1) == x &^ (y-1)
-	y1 := nat(nil).sub(y.abs, natOne)
-	z.abs = z.abs.andNot(x.abs, y1)
-	z.neg = false
-	return z
-}
-
-// AndNot sets z = x &^ y and returns z.
-func (z *Int) AndNot(x, y *Int) *Int {
-	if x.neg == y.neg {
-		if x.neg {
-			// (-x) &^ (-y) == ^(x-1) &^ ^(y-1) == ^(x-1) & (y-1) == (y-1) &^ (x-1)
-			x1 := nat(nil).sub(x.abs, natOne)
-			y1 := nat(nil).sub(y.abs, natOne)
-			z.abs = z.abs.andNot(y1, x1)
-			z.neg = false
-			return z
-		}
-
-		// x &^ y == x &^ y
-		z.abs = z.abs.andNot(x.abs, y.abs)
-		z.neg = false
-		return z
-	}
-
-	if x.neg {
-		// (-x) &^ y == ^(x-1) &^ y == ^(x-1) & ^y == ^((x-1) | y) == -(((x-1) | y) + 1)
-		x1 := nat(nil).sub(x.abs, natOne)
-		z.abs = z.abs.add(z.abs.or(x1, y.abs), natOne)
-		z.neg = true // z cannot be zero if x is negative and y is positive
-		return z
-	}
-
-	// x &^ (-y) == x &^ ^(y-1) == x & (y-1)
-	y1 := nat(nil).sub(y.abs, natOne)
-	z.abs = z.abs.and(x.abs, y1)
-	z.neg = false
-	return z
-}
-
-// Or sets z = x | y and returns z.
-func (z *Int) Or(x, y *Int) *Int {
-	if x.neg == y.neg {
-		if x.neg {
-			// (-x) | (-y) == ^(x-1) | ^(y-1) == ^((x-1) & (y-1)) == -(((x-1) & (y-1)) + 1)
-			x1 := nat(nil).sub(x.abs, natOne)
-			y1 := nat(nil).sub(y.abs, natOne)
-			z.abs = z.abs.add(z.abs.and(x1, y1), natOne)
-			z.neg = true // z cannot be zero if x and y are negative
-			return z
-		}
-
-		// x | y == x | y
-		z.abs = z.abs.or(x.abs, y.abs)
-		z.neg = false
-		return z
-	}
-
-	// x.neg != y.neg
-	if x.neg {
-		x, y = y, x // | is symmetric
-	}
-
-	// x | (-y) == x | ^(y-1) == ^((y-1) &^ x) == -(^((y-1) &^ x) + 1)
-	y1 := nat(nil).sub(y.abs, natOne)
-	z.abs = z.abs.add(z.abs.andNot(y1, x.abs), natOne)
-	z.neg = true // z cannot be zero if one of x or y is negative
-	return z
-}
-
-// Xor sets z = x ^ y and returns z.
-func (z *Int) Xor(x, y *Int) *Int {
-	if x.neg == y.neg {
-		if x.neg {
-			// (-x) ^ (-y) == ^(x-1) ^ ^(y-1) == (x-1) ^ (y-1)
-			x1 := nat(nil).sub(x.abs, natOne)
-			y1 := nat(nil).sub(y.abs, natOne)
-			z.abs = z.abs.xor(x1, y1)
-			z.neg = false
-			return z
-		}
-
-		// x ^ y == x ^ y
-		z.abs = z.abs.xor(x.abs, y.abs)
-		z.neg = false
-		return z
-	}
-
-	// x.neg != y.neg
-	if x.neg {
-		x, y = y, x // ^ is symmetric
-	}
-
-	// x ^ (-y) == x ^ ^(y-1) == ^(x ^ (y-1)) == -((x ^ (y-1)) + 1)
-	y1 := nat(nil).sub(y.abs, natOne)
-	z.abs = z.abs.add(z.abs.xor(x.abs, y1), natOne)
-	z.neg = true // z cannot be zero if only one of x or y is negative
-	return z
-}
-
-// Not sets z = ^x and returns z.
-func (z *Int) Not(x *Int) *Int {
-	if x.neg {
-		// ^(-x) == ^(^(x-1)) == x-1
-		z.abs = z.abs.sub(x.abs, natOne)
-		z.neg = false
-		return z
-	}
-
-	// ^x == -x-1 == -(x+1)
-	z.abs = z.abs.add(x.abs, natOne)
-	z.neg = true // z cannot be zero if x is positive
-	return z
-}
-
-// Sqrt sets z to ⌊√x⌋, the largest integer such that z² ≤ x, and returns z.
-// It panics if x is negative.
-func (z *Int) Sqrt(x *Int) *Int {
-	if x.neg {
-		panic("square root of negative number")
-	}
-	z.neg = false
-	z.abs = z.abs.sqrt(x.abs)
-	return z
-}
diff --git a/contrib/go/_std_1.18/src/math/big/intconv.go b/contrib/go/_std_1.18/src/math/big/intconv.go
deleted file mode 100644
index 0567284105..0000000000
--- a/contrib/go/_std_1.18/src/math/big/intconv.go
+++ /dev/null
@@ -1,257 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file implements int-to-string conversion functions.
-
-package big
-
-import (
-	"errors"
-	"fmt"
-	"io"
-)
-
-// Text returns the string representation of x in the given base.
-// Base must be between 2 and 62, inclusive. The result uses the
-// lower-case letters 'a' to 'z' for digit values 10 to 35, and
-// the upper-case letters 'A' to 'Z' for digit values 36 to 61.
-// No prefix (such as "0x") is added to the string. If x is a nil
-// pointer it returns "<nil>".
-func (x *Int) Text(base int) string {
-	if x == nil {
-		return "<nil>"
-	}
-	return string(x.abs.itoa(x.neg, base))
-}
-
-// Append appends the string representation of x, as generated by
-// x.Text(base), to buf and returns the extended buffer.
-func (x *Int) Append(buf []byte, base int) []byte {
-	if x == nil {
-		return append(buf, "<nil>"...)
-	}
-	return append(buf, x.abs.itoa(x.neg, base)...)
-}
-
-// String returns the decimal representation of x as generated by
-// x.Text(10).
-func (x *Int) String() string {
-	return x.Text(10)
-}
-
-// write count copies of text to s
-func writeMultiple(s fmt.State, text string, count int) {
-	if len(text) > 0 {
-		b := []byte(text)
-		for ; count > 0; count-- {
-			s.Write(b)
-		}
-	}
-}
-
-var _ fmt.Formatter = intOne // *Int must implement fmt.Formatter
-
-// Format implements fmt.Formatter. It accepts the formats
-// 'b' (binary), 'o' (octal with 0 prefix), 'O' (octal with 0o prefix),
-// 'd' (decimal), 'x' (lowercase hexadecimal), and
-// 'X' (uppercase hexadecimal).
-// Also supported are the full suite of package fmt's format
-// flags for integral types, including '+' and ' ' for sign
-// control, '#' for leading zero in octal and for hexadecimal,
-// a leading "0x" or "0X" for "%#x" and "%#X" respectively,
-// specification of minimum digits precision, output field
-// width, space or zero padding, and '-' for left or right
-// justification.
-//
-func (x *Int) Format(s fmt.State, ch rune) {
-	// determine base
-	var base int
-	switch ch {
-	case 'b':
-		base = 2
-	case 'o', 'O':
-		base = 8
-	case 'd', 's', 'v':
-		base = 10
-	case 'x', 'X':
-		base = 16
-	default:
-		// unknown format
-		fmt.Fprintf(s, "%%!%c(big.Int=%s)", ch, x.String())
-		return
-	}
-
-	if x == nil {
-		fmt.Fprint(s, "<nil>")
-		return
-	}
-
-	// determine sign character
-	sign := ""
-	switch {
-	case x.neg:
-		sign = "-"
-	case s.Flag('+'): // supersedes ' ' when both specified
-		sign = "+"
-	case s.Flag(' '):
-		sign = " "
-	}
-
-	// determine prefix characters for indicating output base
-	prefix := ""
-	if s.Flag('#') {
-		switch ch {
-		case 'b': // binary
-			prefix = "0b"
-		case 'o': // octal
-			prefix = "0"
-		case 'x': // hexadecimal
-			prefix = "0x"
-		case 'X':
-			prefix = "0X"
-		}
-	}
-	if ch == 'O' {
-		prefix = "0o"
-	}
-
-	digits := x.abs.utoa(base)
-	if ch == 'X' {
-		// faster than bytes.ToUpper
-		for i, d := range digits {
-			if 'a' <= d && d <= 'z' {
-				digits[i] = 'A' + (d - 'a')
-			}
-		}
-	}
-
-	// number of characters for the three classes of number padding
-	var left int  // space characters to left of digits for right justification ("%8d")
-	var zeros int // zero characters (actually cs[0]) as left-most digits ("%.8d")
-	var right int // space characters to right of digits for left justification ("%-8d")
-
-	// determine number padding from precision: the least number of digits to output
-	precision, precisionSet := s.Precision()
-	if precisionSet {
-		switch {
-		case len(digits) < precision:
-			zeros = precision - len(digits) // count of zero padding
-		case len(digits) == 1 && digits[0] == '0' && precision == 0:
-			return // print nothing if zero value (x == 0) and zero precision ("." or ".0")
-		}
-	}
-
-	// determine field pad from width: the least number of characters to output
-	length := len(sign) + len(prefix) + zeros + len(digits)
-	if width, widthSet := s.Width(); widthSet && length < width { // pad as specified
-		switch d := width - length; {
-		case s.Flag('-'):
-			// pad on the right with spaces; supersedes '0' when both specified
-			right = d
-		case s.Flag('0') && !precisionSet:
-			// pad with zeros unless precision also specified
-			zeros = d
-		default:
-			// pad on the left with spaces
-			left = d
-		}
-	}
-
-	// print number as [left pad][sign][prefix][zero pad][digits][right pad]
-	writeMultiple(s, " ", left)
-	writeMultiple(s, sign, 1)
-	writeMultiple(s, prefix, 1)
-	writeMultiple(s, "0", zeros)
-	s.Write(digits)
-	writeMultiple(s, " ", right)
-}
-
-// scan sets z to the integer value corresponding to the longest possible prefix
-// read from r representing a signed integer number in a given conversion base.
-// It returns z, the actual conversion base used, and an error, if any. In the
-// error case, the value of z is undefined but the returned value is nil. The
-// syntax follows the syntax of integer literals in Go.
-//
-// The base argument must be 0 or a value from 2 through MaxBase. If the base
-// is 0, the string prefix determines the actual conversion base. A prefix of
-// ``0b'' or ``0B'' selects base 2; a ``0'', ``0o'', or ``0O'' prefix selects
-// base 8, and a ``0x'' or ``0X'' prefix selects base 16. Otherwise the selected
-// base is 10.
-//
-func (z *Int) scan(r io.ByteScanner, base int) (*Int, int, error) {
-	// determine sign
-	neg, err := scanSign(r)
-	if err != nil {
-		return nil, 0, err
-	}
-
-	// determine mantissa
-	z.abs, base, _, err = z.abs.scan(r, base, false)
-	if err != nil {
-		return nil, base, err
-	}
-	z.neg = len(z.abs) > 0 && neg // 0 has no sign
-
-	return z, base, nil
-}
-
-func scanSign(r io.ByteScanner) (neg bool, err error) {
-	var ch byte
-	if ch, err = r.ReadByte(); err != nil {
-		return false, err
-	}
-	switch ch {
-	case '-':
-		neg = true
-	case '+':
-		// nothing to do
-	default:
-		r.UnreadByte()
-	}
-	return
-}
-
-// byteReader is a local wrapper around fmt.ScanState;
-// it implements the ByteReader interface.
-type byteReader struct {
-	fmt.ScanState
-}
-
-func (r byteReader) ReadByte() (byte, error) {
-	ch, size, err := r.ReadRune()
-	if size != 1 && err == nil {
-		err = fmt.Errorf("invalid rune %#U", ch)
-	}
-	return byte(ch), err
-}
-
-func (r byteReader) UnreadByte() error {
-	return r.UnreadRune()
-}
-
-var _ fmt.Scanner = intOne // *Int must implement fmt.Scanner
-
-// Scan is a support routine for fmt.Scanner; it sets z to the value of
-// the scanned number. It accepts the formats 'b' (binary), 'o' (octal),
-// 'd' (decimal), 'x' (lowercase hexadecimal), and 'X' (uppercase hexadecimal).
-func (z *Int) Scan(s fmt.ScanState, ch rune) error {
-	s.SkipSpace() // skip leading space characters
-	base := 0
-	switch ch {
-	case 'b':
-		base = 2
-	case 'o':
-		base = 8
-	case 'd':
-		base = 10
-	case 'x', 'X':
-		base = 16
-	case 's', 'v':
-		// let scan determine the base
-	default:
-		return errors.New("Int.Scan: invalid verb")
-	}
-	_, _, err := z.scan(byteReader{s}, base)
-	return err
-}
diff --git a/contrib/go/_std_1.18/src/math/big/intmarsh.go b/contrib/go/_std_1.18/src/math/big/intmarsh.go
deleted file mode 100644
index c1422e2710..0000000000
--- a/contrib/go/_std_1.18/src/math/big/intmarsh.go
+++ /dev/null
@@ -1,80 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file implements encoding/decoding of Ints.
-
-package big
-
-import (
-	"bytes"
-	"fmt"
-)
-
-// Gob codec version. Permits backward-compatible changes to the encoding.
-const intGobVersion byte = 1
-
-// GobEncode implements the gob.GobEncoder interface.
-func (x *Int) GobEncode() ([]byte, error) {
-	if x == nil {
-		return nil, nil
-	}
-	buf := make([]byte, 1+len(x.abs)*_S) // extra byte for version and sign bit
-	i := x.abs.bytes(buf) - 1            // i >= 0
-	b := intGobVersion << 1              // make space for sign bit
-	if x.neg {
-		b |= 1
-	}
-	buf[i] = b
-	return buf[i:], nil
-}
-
-// GobDecode implements the gob.GobDecoder interface.
-func (z *Int) GobDecode(buf []byte) error {
-	if len(buf) == 0 {
-		// Other side sent a nil or default value.
-		*z = Int{}
-		return nil
-	}
-	b := buf[0]
-	if b>>1 != intGobVersion {
-		return fmt.Errorf("Int.GobDecode: encoding version %d not supported", b>>1)
-	}
-	z.neg = b&1 != 0
-	z.abs = z.abs.setBytes(buf[1:])
-	return nil
-}
-
-// MarshalText implements the encoding.TextMarshaler interface.
-func (x *Int) MarshalText() (text []byte, err error) {
-	if x == nil {
-		return []byte("<nil>"), nil
-	}
-	return x.abs.itoa(x.neg, 10), nil
-}
-
-// UnmarshalText implements the encoding.TextUnmarshaler interface.
-func (z *Int) UnmarshalText(text []byte) error {
-	if _, ok := z.setFromScanner(bytes.NewReader(text), 0); !ok {
-		return fmt.Errorf("math/big: cannot unmarshal %q into a *big.Int", text)
-	}
-	return nil
-}
-
-// The JSON marshalers are only here for API backward compatibility
-// (programs that explicitly look for these two methods). JSON works
-// fine with the TextMarshaler only.
-
-// MarshalJSON implements the json.Marshaler interface.
-func (x *Int) MarshalJSON() ([]byte, error) {
-	return x.MarshalText()
-}
-
-// UnmarshalJSON implements the json.Unmarshaler interface.
-func (z *Int) UnmarshalJSON(text []byte) error {
-	// Ignore null, like in the main JSON package.
-	if string(text) == "null" {
-		return nil
-	}
-	return z.UnmarshalText(text)
-}
diff --git a/contrib/go/_std_1.18/src/math/big/nat.go b/contrib/go/_std_1.18/src/math/big/nat.go
deleted file mode 100644
index 140c619c8c..0000000000
--- a/contrib/go/_std_1.18/src/math/big/nat.go
+++ /dev/null
@@ -1,1244 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file implements unsigned multi-precision integers (natural
-// numbers). They are the building blocks for the implementation
-// of signed integers, rationals, and floating-point numbers.
-//
-// Caution: This implementation relies on the function "alias"
-//          which assumes that (nat) slice capacities are never
-//          changed (no 3-operand slice expressions). If that
-//          changes, alias needs to be updated for correctness.
-
-package big
-
-import (
-	"encoding/binary"
-	"math/bits"
-	"math/rand"
-	"sync"
-)
-
-// An unsigned integer x of the form
-//
-//   x = x[n-1]*_B^(n-1) + x[n-2]*_B^(n-2) + ... + x[1]*_B + x[0]
-//
-// with 0 <= x[i] < _B and 0 <= i < n is stored in a slice of length n,
-// with the digits x[i] as the slice elements.
-//
-// A number is normalized if the slice contains no leading 0 digits.
-// During arithmetic operations, denormalized values may occur but are
-// always normalized before returning the final result. The normalized
-// representation of 0 is the empty or nil slice (length = 0).
-//
-type nat []Word
-
-var (
-	natOne  = nat{1}
-	natTwo  = nat{2}
-	natFive = nat{5}
-	natTen  = nat{10}
-)
-
-func (z nat) clear() {
-	for i := range z {
-		z[i] = 0
-	}
-}
-
-func (z nat) norm() nat {
-	i := len(z)
-	for i > 0 && z[i-1] == 0 {
-		i--
-	}
-	return z[0:i]
-}
-
-func (z nat) make(n int) nat {
-	if n <= cap(z) {
-		return z[:n] // reuse z
-	}
-	if n == 1 {
-		// Most nats start small and stay that way; don't over-allocate.
-		return make(nat, 1)
-	}
-	// Choosing a good value for e has significant performance impact
-	// because it increases the chance that a value can be reused.
-	const e = 4 // extra capacity
-	return make(nat, n, n+e)
-}
-
-func (z nat) setWord(x Word) nat {
-	if x == 0 {
-		return z[:0]
-	}
-	z = z.make(1)
-	z[0] = x
-	return z
-}
-
-func (z nat) setUint64(x uint64) nat {
-	// single-word value
-	if w := Word(x); uint64(w) == x {
-		return z.setWord(w)
-	}
-	// 2-word value
-	z = z.make(2)
-	z[1] = Word(x >> 32)
-	z[0] = Word(x)
-	return z
-}
-
-func (z nat) set(x nat) nat {
-	z = z.make(len(x))
-	copy(z, x)
-	return z
-}
-
-func (z nat) add(x, y nat) nat {
-	m := len(x)
-	n := len(y)
-
-	switch {
-	case m < n:
-		return z.add(y, x)
-	case m == 0:
-		// n == 0 because m >= n; result is 0
-		return z[:0]
-	case n == 0:
-		// result is x
-		return z.set(x)
-	}
-	// m > 0
-
-	z = z.make(m + 1)
-	c := addVV(z[0:n], x, y)
-	if m > n {
-		c = addVW(z[n:m], x[n:], c)
-	}
-	z[m] = c
-
-	return z.norm()
-}
-
-func (z nat) sub(x, y nat) nat {
-	m := len(x)
-	n := len(y)
-
-	switch {
-	case m < n:
-		panic("underflow")
-	case m == 0:
-		// n == 0 because m >= n; result is 0
-		return z[:0]
-	case n == 0:
-		// result is x
-		return z.set(x)
-	}
-	// m > 0
-
-	z = z.make(m)
-	c := subVV(z[0:n], x, y)
-	if m > n {
-		c = subVW(z[n:], x[n:], c)
-	}
-	if c != 0 {
-		panic("underflow")
-	}
-
-	return z.norm()
-}
-
-func (x nat) cmp(y nat) (r int) {
-	m := len(x)
-	n := len(y)
-	if m != n || m == 0 {
-		switch {
-		case m < n:
-			r = -1
-		case m > n:
-			r = 1
-		}
-		return
-	}
-
-	i := m - 1
-	for i > 0 && x[i] == y[i] {
-		i--
-	}
-
-	switch {
-	case x[i] < y[i]:
-		r = -1
-	case x[i] > y[i]:
-		r = 1
-	}
-	return
-}
-
-func (z nat) mulAddWW(x nat, y, r Word) nat {
-	m := len(x)
-	if m == 0 || y == 0 {
-		return z.setWord(r) // result is r
-	}
-	// m > 0
-
-	z = z.make(m + 1)
-	z[m] = mulAddVWW(z[0:m], x, y, r)
-
-	return z.norm()
-}
-
-// basicMul multiplies x and y and leaves the result in z.
-// The (non-normalized) result is placed in z[0 : len(x) + len(y)].
-func basicMul(z, x, y nat) {
-	z[0 : len(x)+len(y)].clear() // initialize z
-	for i, d := range y {
-		if d != 0 {
-			z[len(x)+i] = addMulVVW(z[i:i+len(x)], x, d)
-		}
-	}
-}
-
-// montgomery computes z mod m = x*y*2**(-n*_W) mod m,
-// assuming k = -1/m mod 2**_W.
-// z is used for storing the result which is returned;
-// z must not alias x, y or m.
-// See Gueron, "Efficient Software Implementations of Modular Exponentiation".
-// https://eprint.iacr.org/2011/239.pdf
-// In the terminology of that paper, this is an "Almost Montgomery Multiplication":
-// x and y are required to satisfy 0 <= z < 2**(n*_W) and then the result
-// z is guaranteed to satisfy 0 <= z < 2**(n*_W), but it may not be < m.
-func (z nat) montgomery(x, y, m nat, k Word, n int) nat {
-	// This code assumes x, y, m are all the same length, n.
-	// (required by addMulVVW and the for loop).
-	// It also assumes that x, y are already reduced mod m,
-	// or else the result will not be properly reduced.
-	if len(x) != n || len(y) != n || len(m) != n {
-		panic("math/big: mismatched montgomery number lengths")
-	}
-	z = z.make(n * 2)
-	z.clear()
-	var c Word
-	for i := 0; i < n; i++ {
-		d := y[i]
-		c2 := addMulVVW(z[i:n+i], x, d)
-		t := z[i] * k
-		c3 := addMulVVW(z[i:n+i], m, t)
-		cx := c + c2
-		cy := cx + c3
-		z[n+i] = cy
-		if cx < c2 || cy < c3 {
-			c = 1
-		} else {
-			c = 0
-		}
-	}
-	if c != 0 {
-		subVV(z[:n], z[n:], m)
-	} else {
-		copy(z[:n], z[n:])
-	}
-	return z[:n]
-}
-
-// Fast version of z[0:n+n>>1].add(z[0:n+n>>1], x[0:n]) w/o bounds checks.
-// Factored out for readability - do not use outside karatsuba.
-func karatsubaAdd(z, x nat, n int) {
-	if c := addVV(z[0:n], z, x); c != 0 {
-		addVW(z[n:n+n>>1], z[n:], c)
-	}
-}
-
-// Like karatsubaAdd, but does subtract.
-func karatsubaSub(z, x nat, n int) {
-	if c := subVV(z[0:n], z, x); c != 0 {
-		subVW(z[n:n+n>>1], z[n:], c)
-	}
-}
-
-// Operands that are shorter than karatsubaThreshold are multiplied using
-// "grade school" multiplication; for longer operands the Karatsuba algorithm
-// is used.
-var karatsubaThreshold = 40 // computed by calibrate_test.go
-
-// karatsuba multiplies x and y and leaves the result in z.
-// Both x and y must have the same length n and n must be a
-// power of 2. The result vector z must have len(z) >= 6*n.
-// The (non-normalized) result is placed in z[0 : 2*n].
-func karatsuba(z, x, y nat) {
-	n := len(y)
-
-	// Switch to basic multiplication if numbers are odd or small.
-	// (n is always even if karatsubaThreshold is even, but be
-	// conservative)
-	if n&1 != 0 || n < karatsubaThreshold || n < 2 {
-		basicMul(z, x, y)
-		return
-	}
-	// n&1 == 0 && n >= karatsubaThreshold && n >= 2
-
-	// Karatsuba multiplication is based on the observation that
-	// for two numbers x and y with:
-	//
-	//   x = x1*b + x0
-	//   y = y1*b + y0
-	//
-	// the product x*y can be obtained with 3 products z2, z1, z0
-	// instead of 4:
-	//
-	//   x*y = x1*y1*b*b + (x1*y0 + x0*y1)*b + x0*y0
-	//       =    z2*b*b +              z1*b +    z0
-	//
-	// with:
-	//
-	//   xd = x1 - x0
-	//   yd = y0 - y1
-	//
-	//   z1 =      xd*yd                    + z2 + z0
-	//      = (x1-x0)*(y0 - y1)             + z2 + z0
-	//      = x1*y0 - x1*y1 - x0*y0 + x0*y1 + z2 + z0
-	//      = x1*y0 -    z2 -    z0 + x0*y1 + z2 + z0
-	//      = x1*y0                 + x0*y1
-
-	// split x, y into "digits"
-	n2 := n >> 1              // n2 >= 1
-	x1, x0 := x[n2:], x[0:n2] // x = x1*b + y0
-	y1, y0 := y[n2:], y[0:n2] // y = y1*b + y0
-
-	// z is used for the result and temporary storage:
-	//
-	//   6*n     5*n     4*n     3*n     2*n     1*n     0*n
-	// z = [z2 copy|z0 copy| xd*yd | yd:xd | x1*y1 | x0*y0 ]
-	//
-	// For each recursive call of karatsuba, an unused slice of
-	// z is passed in that has (at least) half the length of the
-	// caller's z.
-
-	// compute z0 and z2 with the result "in place" in z
-	karatsuba(z, x0, y0)     // z0 = x0*y0
-	karatsuba(z[n:], x1, y1) // z2 = x1*y1
-
-	// compute xd (or the negative value if underflow occurs)
-	s := 1 // sign of product xd*yd
-	xd := z[2*n : 2*n+n2]
-	if subVV(xd, x1, x0) != 0 { // x1-x0
-		s = -s
-		subVV(xd, x0, x1) // x0-x1
-	}
-
-	// compute yd (or the negative value if underflow occurs)
-	yd := z[2*n+n2 : 3*n]
-	if subVV(yd, y0, y1) != 0 { // y0-y1
-		s = -s
-		subVV(yd, y1, y0) // y1-y0
-	}
-
-	// p = (x1-x0)*(y0-y1) == x1*y0 - x1*y1 - x0*y0 + x0*y1 for s > 0
-	// p = (x0-x1)*(y0-y1) == x0*y0 - x0*y1 - x1*y0 + x1*y1 for s < 0
-	p := z[n*3:]
-	karatsuba(p, xd, yd)
-
-	// save original z2:z0
-	// (ok to use upper half of z since we're done recursing)
-	r := z[n*4:]
-	copy(r, z[:n*2])
-
-	// add up all partial products
-	//
-	//   2*n     n     0
-	// z = [ z2  | z0  ]
-	//   +    [ z0  ]
-	//   +    [ z2  ]
-	//   +    [  p  ]
-	//
-	karatsubaAdd(z[n2:], r, n)
-	karatsubaAdd(z[n2:], r[n:], n)
-	if s > 0 {
-		karatsubaAdd(z[n2:], p, n)
-	} else {
-		karatsubaSub(z[n2:], p, n)
-	}
-}
-
-// alias reports whether x and y share the same base array.
-// Note: alias assumes that the capacity of underlying arrays
-//       is never changed for nat values; i.e. that there are
-//       no 3-operand slice expressions in this code (or worse,
-//       reflect-based operations to the same effect).
-func alias(x, y nat) bool {
-	return cap(x) > 0 && cap(y) > 0 && &x[0:cap(x)][cap(x)-1] == &y[0:cap(y)][cap(y)-1]
-}
-
-// addAt implements z += x<<(_W*i); z must be long enough.
-// (we don't use nat.add because we need z to stay the same
-// slice, and we don't need to normalize z after each addition)
-func addAt(z, x nat, i int) {
-	if n := len(x); n > 0 {
-		if c := addVV(z[i:i+n], z[i:], x); c != 0 {
-			j := i + n
-			if j < len(z) {
-				addVW(z[j:], z[j:], c)
-			}
-		}
-	}
-}
-
-func max(x, y int) int {
-	if x > y {
-		return x
-	}
-	return y
-}
-
-// karatsubaLen computes an approximation to the maximum k <= n such that
-// k = p<<i for a number p <= threshold and an i >= 0. Thus, the
-// result is the largest number that can be divided repeatedly by 2 before
-// becoming about the value of threshold.
-func karatsubaLen(n, threshold int) int {
-	i := uint(0)
-	for n > threshold {
-		n >>= 1
-		i++
-	}
-	return n << i
-}
-
-func (z nat) mul(x, y nat) nat {
-	m := len(x)
-	n := len(y)
-
-	switch {
-	case m < n:
-		return z.mul(y, x)
-	case m == 0 || n == 0:
-		return z[:0]
-	case n == 1:
-		return z.mulAddWW(x, y[0], 0)
-	}
-	// m >= n > 1
-
-	// determine if z can be reused
-	if alias(z, x) || alias(z, y) {
-		z = nil // z is an alias for x or y - cannot reuse
-	}
-
-	// use basic multiplication if the numbers are small
-	if n < karatsubaThreshold {
-		z = z.make(m + n)
-		basicMul(z, x, y)
-		return z.norm()
-	}
-	// m >= n && n >= karatsubaThreshold && n >= 2
-
-	// determine Karatsuba length k such that
-	//
-	//   x = xh*b + x0  (0 <= x0 < b)
-	//   y = yh*b + y0  (0 <= y0 < b)
-	//   b = 1<<(_W*k)  ("base" of digits xi, yi)
-	//
-	k := karatsubaLen(n, karatsubaThreshold)
-	// k <= n
-
-	// multiply x0 and y0 via Karatsuba
-	x0 := x[0:k]              // x0 is not normalized
-	y0 := y[0:k]              // y0 is not normalized
-	z = z.make(max(6*k, m+n)) // enough space for karatsuba of x0*y0 and full result of x*y
-	karatsuba(z, x0, y0)
-	z = z[0 : m+n]  // z has final length but may be incomplete
-	z[2*k:].clear() // upper portion of z is garbage (and 2*k <= m+n since k <= n <= m)
-
-	// If xh != 0 or yh != 0, add the missing terms to z. For
-	//
-	//   xh = xi*b^i + ... + x2*b^2 + x1*b (0 <= xi < b)
-	//   yh =                         y1*b (0 <= y1 < b)
-	//
-	// the missing terms are
-	//
-	//   x0*y1*b and xi*y0*b^i, xi*y1*b^(i+1) for i > 0
-	//
-	// since all the yi for i > 1 are 0 by choice of k: If any of them
-	// were > 0, then yh >= b^2 and thus y >= b^2. Then k' = k*2 would
-	// be a larger valid threshold contradicting the assumption about k.
-	//
-	if k < n || m != n {
-		tp := getNat(3 * k)
-		t := *tp
-
-		// add x0*y1*b
-		x0 := x0.norm()
-		y1 := y[k:]       // y1 is normalized because y is
-		t = t.mul(x0, y1) // update t so we don't lose t's underlying array
-		addAt(z, t, k)
-
-		// add xi*y0<<i, xi*y1*b<<(i+k)
-		y0 := y0.norm()
-		for i := k; i < len(x); i += k {
-			xi := x[i:]
-			if len(xi) > k {
-				xi = xi[:k]
-			}
-			xi = xi.norm()
-			t = t.mul(xi, y0)
-			addAt(z, t, i)
-			t = t.mul(xi, y1)
-			addAt(z, t, i+k)
-		}
-
-		putNat(tp)
-	}
-
-	return z.norm()
-}
-
-// basicSqr sets z = x*x and is asymptotically faster than basicMul
-// by about a factor of 2, but slower for small arguments due to overhead.
-// Requirements: len(x) > 0, len(z) == 2*len(x)
-// The (non-normalized) result is placed in z.
-func basicSqr(z, x nat) {
-	n := len(x)
-	tp := getNat(2 * n)
-	t := *tp // temporary variable to hold the products
-	t.clear()
-	z[1], z[0] = mulWW(x[0], x[0]) // the initial square
-	for i := 1; i < n; i++ {
-		d := x[i]
-		// z collects the squares x[i] * x[i]
-		z[2*i+1], z[2*i] = mulWW(d, d)
-		// t collects the products x[i] * x[j] where j < i
-		t[2*i] = addMulVVW(t[i:2*i], x[0:i], d)
-	}
-	t[2*n-1] = shlVU(t[1:2*n-1], t[1:2*n-1], 1) // double the j < i products
-	addVV(z, z, t)                              // combine the result
-	putNat(tp)
-}
-
-// karatsubaSqr squares x and leaves the result in z.
-// len(x) must be a power of 2 and len(z) >= 6*len(x).
-// The (non-normalized) result is placed in z[0 : 2*len(x)].
-//
-// The algorithm and the layout of z are the same as for karatsuba.
-func karatsubaSqr(z, x nat) {
-	n := len(x)
-
-	if n&1 != 0 || n < karatsubaSqrThreshold || n < 2 {
-		basicSqr(z[:2*n], x)
-		return
-	}
-
-	n2 := n >> 1
-	x1, x0 := x[n2:], x[0:n2]
-
-	karatsubaSqr(z, x0)
-	karatsubaSqr(z[n:], x1)
-
-	// s = sign(xd*yd) == -1 for xd != 0; s == 1 for xd == 0
-	xd := z[2*n : 2*n+n2]
-	if subVV(xd, x1, x0) != 0 {
-		subVV(xd, x0, x1)
-	}
-
-	p := z[n*3:]
-	karatsubaSqr(p, xd)
-
-	r := z[n*4:]
-	copy(r, z[:n*2])
-
-	karatsubaAdd(z[n2:], r, n)
-	karatsubaAdd(z[n2:], r[n:], n)
-	karatsubaSub(z[n2:], p, n) // s == -1 for p != 0; s == 1 for p == 0
-}
-
-// Operands that are shorter than basicSqrThreshold are squared using
-// "grade school" multiplication; for operands longer than karatsubaSqrThreshold
-// we use the Karatsuba algorithm optimized for x == y.
-var basicSqrThreshold = 20      // computed by calibrate_test.go
-var karatsubaSqrThreshold = 260 // computed by calibrate_test.go
-
-// z = x*x
-func (z nat) sqr(x nat) nat {
-	n := len(x)
-	switch {
-	case n == 0:
-		return z[:0]
-	case n == 1:
-		d := x[0]
-		z = z.make(2)
-		z[1], z[0] = mulWW(d, d)
-		return z.norm()
-	}
-
-	if alias(z, x) {
-		z = nil // z is an alias for x - cannot reuse
-	}
-
-	if n < basicSqrThreshold {
-		z = z.make(2 * n)
-		basicMul(z, x, x)
-		return z.norm()
-	}
-	if n < karatsubaSqrThreshold {
-		z = z.make(2 * n)
-		basicSqr(z, x)
-		return z.norm()
-	}
-
-	// Use Karatsuba multiplication optimized for x == y.
-	// The algorithm and layout of z are the same as for mul.
-
-	// z = (x1*b + x0)^2 = x1^2*b^2 + 2*x1*x0*b + x0^2
-
-	k := karatsubaLen(n, karatsubaSqrThreshold)
-
-	x0 := x[0:k]
-	z = z.make(max(6*k, 2*n))
-	karatsubaSqr(z, x0) // z = x0^2
-	z = z[0 : 2*n]
-	z[2*k:].clear()
-
-	if k < n {
-		tp := getNat(2 * k)
-		t := *tp
-		x0 := x0.norm()
-		x1 := x[k:]
-		t = t.mul(x0, x1)
-		addAt(z, t, k)
-		addAt(z, t, k) // z = 2*x1*x0*b + x0^2
-		t = t.sqr(x1)
-		addAt(z, t, 2*k) // z = x1^2*b^2 + 2*x1*x0*b + x0^2
-		putNat(tp)
-	}
-
-	return z.norm()
-}
-
-// mulRange computes the product of all the unsigned integers in the
-// range [a, b] inclusively. If a > b (empty range), the result is 1.
-func (z nat) mulRange(a, b uint64) nat {
-	switch {
-	case a == 0:
-		// cut long ranges short (optimization)
-		return z.setUint64(0)
-	case a > b:
-		return z.setUint64(1)
-	case a == b:
-		return z.setUint64(a)
-	case a+1 == b:
-		return z.mul(nat(nil).setUint64(a), nat(nil).setUint64(b))
-	}
-	m := (a + b) / 2
-	return z.mul(nat(nil).mulRange(a, m), nat(nil).mulRange(m+1, b))
-}
-
-// getNat returns a *nat of len n. The contents may not be zero.
-// The pool holds *nat to avoid allocation when converting to interface{}.
-func getNat(n int) *nat {
-	var z *nat
-	if v := natPool.Get(); v != nil {
-		z = v.(*nat)
-	}
-	if z == nil {
-		z = new(nat)
-	}
-	*z = z.make(n)
-	return z
-}
-
-func putNat(x *nat) {
-	natPool.Put(x)
-}
-
-var natPool sync.Pool
-
-// Length of x in bits. x must be normalized.
-func (x nat) bitLen() int {
-	if i := len(x) - 1; i >= 0 {
-		return i*_W + bits.Len(uint(x[i]))
-	}
-	return 0
-}
-
-// trailingZeroBits returns the number of consecutive least significant zero
-// bits of x.
-func (x nat) trailingZeroBits() uint {
-	if len(x) == 0 {
-		return 0
-	}
-	var i uint
-	for x[i] == 0 {
-		i++
-	}
-	// x[i] != 0
-	return i*_W + uint(bits.TrailingZeros(uint(x[i])))
-}
-
-func same(x, y nat) bool {
-	return len(x) == len(y) && len(x) > 0 && &x[0] == &y[0]
-}
-
-// z = x << s
-func (z nat) shl(x nat, s uint) nat {
-	if s == 0 {
-		if same(z, x) {
-			return z
-		}
-		if !alias(z, x) {
-			return z.set(x)
-		}
-	}
-
-	m := len(x)
-	if m == 0 {
-		return z[:0]
-	}
-	// m > 0
-
-	n := m + int(s/_W)
-	z = z.make(n + 1)
-	z[n] = shlVU(z[n-m:n], x, s%_W)
-	z[0 : n-m].clear()
-
-	return z.norm()
-}
-
-// z = x >> s
-func (z nat) shr(x nat, s uint) nat {
-	if s == 0 {
-		if same(z, x) {
-			return z
-		}
-		if !alias(z, x) {
-			return z.set(x)
-		}
-	}
-
-	m := len(x)
-	n := m - int(s/_W)
-	if n <= 0 {
-		return z[:0]
-	}
-	// n > 0
-
-	z = z.make(n)
-	shrVU(z, x[m-n:], s%_W)
-
-	return z.norm()
-}
-
-func (z nat) setBit(x nat, i uint, b uint) nat {
-	j := int(i / _W)
-	m := Word(1) << (i % _W)
-	n := len(x)
-	switch b {
-	case 0:
-		z = z.make(n)
-		copy(z, x)
-		if j >= n {
-			// no need to grow
-			return z
-		}
-		z[j] &^= m
-		return z.norm()
-	case 1:
-		if j >= n {
-			z = z.make(j + 1)
-			z[n:].clear()
-		} else {
-			z = z.make(n)
-		}
-		copy(z, x)
-		z[j] |= m
-		// no need to normalize
-		return z
-	}
-	panic("set bit is not 0 or 1")
-}
-
-// bit returns the value of the i'th bit, with lsb == bit 0.
-func (x nat) bit(i uint) uint {
-	j := i / _W
-	if j >= uint(len(x)) {
-		return 0
-	}
-	// 0 <= j < len(x)
-	return uint(x[j] >> (i % _W) & 1)
-}
-
-// sticky returns 1 if there's a 1 bit within the
-// i least significant bits, otherwise it returns 0.
-func (x nat) sticky(i uint) uint {
-	j := i / _W
-	if j >= uint(len(x)) {
-		if len(x) == 0 {
-			return 0
-		}
-		return 1
-	}
-	// 0 <= j < len(x)
-	for _, x := range x[:j] {
-		if x != 0 {
-			return 1
-		}
-	}
-	if x[j]<<(_W-i%_W) != 0 {
-		return 1
-	}
-	return 0
-}
-
-func (z nat) and(x, y nat) nat {
-	m := len(x)
-	n := len(y)
-	if m > n {
-		m = n
-	}
-	// m <= n
-
-	z = z.make(m)
-	for i := 0; i < m; i++ {
-		z[i] = x[i] & y[i]
-	}
-
-	return z.norm()
-}
-
-func (z nat) andNot(x, y nat) nat {
-	m := len(x)
-	n := len(y)
-	if n > m {
-		n = m
-	}
-	// m >= n
-
-	z = z.make(m)
-	for i := 0; i < n; i++ {
-		z[i] = x[i] &^ y[i]
-	}
-	copy(z[n:m], x[n:m])
-
-	return z.norm()
-}
-
-func (z nat) or(x, y nat) nat {
-	m := len(x)
-	n := len(y)
-	s := x
-	if m < n {
-		n, m = m, n
-		s = y
-	}
-	// m >= n
-
-	z = z.make(m)
-	for i := 0; i < n; i++ {
-		z[i] = x[i] | y[i]
-	}
-	copy(z[n:m], s[n:m])
-
-	return z.norm()
-}
-
-func (z nat) xor(x, y nat) nat {
-	m := len(x)
-	n := len(y)
-	s := x
-	if m < n {
-		n, m = m, n
-		s = y
-	}
-	// m >= n
-
-	z = z.make(m)
-	for i := 0; i < n; i++ {
-		z[i] = x[i] ^ y[i]
-	}
-	copy(z[n:m], s[n:m])
-
-	return z.norm()
-}
-
-// random creates a random integer in [0..limit), using the space in z if
-// possible. n is the bit length of limit.
-func (z nat) random(rand *rand.Rand, limit nat, n int) nat {
-	if alias(z, limit) {
-		z = nil // z is an alias for limit - cannot reuse
-	}
-	z = z.make(len(limit))
-
-	bitLengthOfMSW := uint(n % _W)
-	if bitLengthOfMSW == 0 {
-		bitLengthOfMSW = _W
-	}
-	mask := Word((1 << bitLengthOfMSW) - 1)
-
-	for {
-		switch _W {
-		case 32:
-			for i := range z {
-				z[i] = Word(rand.Uint32())
-			}
-		case 64:
-			for i := range z {
-				z[i] = Word(rand.Uint32()) | Word(rand.Uint32())<<32
-			}
-		default:
-			panic("unknown word size")
-		}
-		z[len(limit)-1] &= mask
-		if z.cmp(limit) < 0 {
-			break
-		}
-	}
-
-	return z.norm()
-}
-
-// If m != 0 (i.e., len(m) != 0), expNN sets z to x**y mod m;
-// otherwise it sets z to x**y. The result is the value of z.
-func (z nat) expNN(x, y, m nat) nat {
-	if alias(z, x) || alias(z, y) {
-		// We cannot allow in-place modification of x or y.
-		z = nil
-	}
-
-	// x**y mod 1 == 0
-	if len(m) == 1 && m[0] == 1 {
-		return z.setWord(0)
-	}
-	// m == 0 || m > 1
-
-	// x**0 == 1
-	if len(y) == 0 {
-		return z.setWord(1)
-	}
-	// y > 0
-
-	// x**1 mod m == x mod m
-	if len(y) == 1 && y[0] == 1 && len(m) != 0 {
-		_, z = nat(nil).div(z, x, m)
-		return z
-	}
-	// y > 1
-
-	if len(m) != 0 {
-		// We likely end up being as long as the modulus.
-		z = z.make(len(m))
-	}
-	z = z.set(x)
-
-	// If the base is non-trivial and the exponent is large, we use
-	// 4-bit, windowed exponentiation. This involves precomputing 14 values
-	// (x^2...x^15) but then reduces the number of multiply-reduces by a
-	// third. Even for a 32-bit exponent, this reduces the number of
-	// operations. Uses Montgomery method for odd moduli.
-	if x.cmp(natOne) > 0 && len(y) > 1 && len(m) > 0 {
-		if m[0]&1 == 1 {
-			return z.expNNMontgomery(x, y, m)
-		}
-		return z.expNNWindowed(x, y, m)
-	}
-
-	v := y[len(y)-1] // v > 0 because y is normalized and y > 0
-	shift := nlz(v) + 1
-	v <<= shift
-	var q nat
-
-	const mask = 1 << (_W - 1)
-
-	// We walk through the bits of the exponent one by one. Each time we
-	// see a bit, we square, thus doubling the power. If the bit is a one,
-	// we also multiply by x, thus adding one to the power.
-
-	w := _W - int(shift)
-	// zz and r are used to avoid allocating in mul and div as
-	// otherwise the arguments would alias.
-	var zz, r nat
-	for j := 0; j < w; j++ {
-		zz = zz.sqr(z)
-		zz, z = z, zz
-
-		if v&mask != 0 {
-			zz = zz.mul(z, x)
-			zz, z = z, zz
-		}
-
-		if len(m) != 0 {
-			zz, r = zz.div(r, z, m)
-			zz, r, q, z = q, z, zz, r
-		}
-
-		v <<= 1
-	}
-
-	for i := len(y) - 2; i >= 0; i-- {
-		v = y[i]
-
-		for j := 0; j < _W; j++ {
-			zz = zz.sqr(z)
-			zz, z = z, zz
-
-			if v&mask != 0 {
-				zz = zz.mul(z, x)
-				zz, z = z, zz
-			}
-
-			if len(m) != 0 {
-				zz, r = zz.div(r, z, m)
-				zz, r, q, z = q, z, zz, r
-			}
-
-			v <<= 1
-		}
-	}
-
-	return z.norm()
-}
-
-// expNNWindowed calculates x**y mod m using a fixed, 4-bit window.
-func (z nat) expNNWindowed(x, y, m nat) nat {
-	// zz and r are used to avoid allocating in mul and div as otherwise
-	// the arguments would alias.
-	var zz, r nat
-
-	const n = 4
-	// powers[i] contains x^i.
-	var powers [1 << n]nat
-	powers[0] = natOne
-	powers[1] = x
-	for i := 2; i < 1<<n; i += 2 {
-		p2, p, p1 := &powers[i/2], &powers[i], &powers[i+1]
-		*p = p.sqr(*p2)
-		zz, r = zz.div(r, *p, m)
-		*p, r = r, *p
-		*p1 = p1.mul(*p, x)
-		zz, r = zz.div(r, *p1, m)
-		*p1, r = r, *p1
-	}
-
-	z = z.setWord(1)
-
-	for i := len(y) - 1; i >= 0; i-- {
-		yi := y[i]
-		for j := 0; j < _W; j += n {
-			if i != len(y)-1 || j != 0 {
-				// Unrolled loop for significant performance
-				// gain. Use go test -bench=".*" in crypto/rsa
-				// to check performance before making changes.
-				zz = zz.sqr(z)
-				zz, z = z, zz
-				zz, r = zz.div(r, z, m)
-				z, r = r, z
-
-				zz = zz.sqr(z)
-				zz, z = z, zz
-				zz, r = zz.div(r, z, m)
-				z, r = r, z
-
-				zz = zz.sqr(z)
-				zz, z = z, zz
-				zz, r = zz.div(r, z, m)
-				z, r = r, z
-
-				zz = zz.sqr(z)
-				zz, z = z, zz
-				zz, r = zz.div(r, z, m)
-				z, r = r, z
-			}
-
-			zz = zz.mul(z, powers[yi>>(_W-n)])
-			zz, z = z, zz
-			zz, r = zz.div(r, z, m)
-			z, r = r, z
-
-			yi <<= n
-		}
-	}
-
-	return z.norm()
-}
-
-// expNNMontgomery calculates x**y mod m using a fixed, 4-bit window.
-// Uses Montgomery representation.
-func (z nat) expNNMontgomery(x, y, m nat) nat {
-	numWords := len(m)
-
-	// We want the lengths of x and m to be equal.
-	// It is OK if x >= m as long as len(x) == len(m).
-	if len(x) > numWords {
-		_, x = nat(nil).div(nil, x, m)
-		// Note: now len(x) <= numWords, not guaranteed ==.
-	}
-	if len(x) < numWords {
-		rr := make(nat, numWords)
-		copy(rr, x)
-		x = rr
-	}
-
-	// Ideally the precomputations would be performed outside, and reused
-	// k0 = -m**-1 mod 2**_W. Algorithm from: Dumas, J.G. "On Newton–Raphson
-	// Iteration for Multiplicative Inverses Modulo Prime Powers".
-	k0 := 2 - m[0]
-	t := m[0] - 1
-	for i := 1; i < _W; i <<= 1 {
-		t *= t
-		k0 *= (t + 1)
-	}
-	k0 = -k0
-
-	// RR = 2**(2*_W*len(m)) mod m
-	RR := nat(nil).setWord(1)
-	zz := nat(nil).shl(RR, uint(2*numWords*_W))
-	_, RR = nat(nil).div(RR, zz, m)
-	if len(RR) < numWords {
-		zz = zz.make(numWords)
-		copy(zz, RR)
-		RR = zz
-	}
-	// one = 1, with equal length to that of m
-	one := make(nat, numWords)
-	one[0] = 1
-
-	const n = 4
-	// powers[i] contains x^i
-	var powers [1 << n]nat
-	powers[0] = powers[0].montgomery(one, RR, m, k0, numWords)
-	powers[1] = powers[1].montgomery(x, RR, m, k0, numWords)
-	for i := 2; i < 1<<n; i++ {
-		powers[i] = powers[i].montgomery(powers[i-1], powers[1], m, k0, numWords)
-	}
-
-	// initialize z = 1 (Montgomery 1)
-	z = z.make(numWords)
-	copy(z, powers[0])
-
-	zz = zz.make(numWords)
-
-	// same windowed exponent, but with Montgomery multiplications
-	for i := len(y) - 1; i >= 0; i-- {
-		yi := y[i]
-		for j := 0; j < _W; j += n {
-			if i != len(y)-1 || j != 0 {
-				zz = zz.montgomery(z, z, m, k0, numWords)
-				z = z.montgomery(zz, zz, m, k0, numWords)
-				zz = zz.montgomery(z, z, m, k0, numWords)
-				z = z.montgomery(zz, zz, m, k0, numWords)
-			}
-			zz = zz.montgomery(z, powers[yi>>(_W-n)], m, k0, numWords)
-			z, zz = zz, z
-			yi <<= n
-		}
-	}
-	// convert to regular number
-	zz = zz.montgomery(z, one, m, k0, numWords)
-
-	// One last reduction, just in case.
-	// See golang.org/issue/13907.
-	if zz.cmp(m) >= 0 {
-		// Common case is m has high bit set; in that case,
-		// since zz is the same length as m, there can be just
-		// one multiple of m to remove. Just subtract.
-		// We think that the subtract should be sufficient in general,
-		// so do that unconditionally, but double-check,
-		// in case our beliefs are wrong.
-		// The div is not expected to be reached.
-		zz = zz.sub(zz, m)
-		if zz.cmp(m) >= 0 {
-			_, zz = nat(nil).div(nil, zz, m)
-		}
-	}
-
-	return zz.norm()
-}
-
-// bytes writes the value of z into buf using big-endian encoding.
-// The value of z is encoded in the slice buf[i:]. If the value of z
-// cannot be represented in buf, bytes panics. The number i of unused
-// bytes at the beginning of buf is returned as result.
-func (z nat) bytes(buf []byte) (i int) {
-	i = len(buf)
-	for _, d := range z {
-		for j := 0; j < _S; j++ {
-			i--
-			if i >= 0 {
-				buf[i] = byte(d)
-			} else if byte(d) != 0 {
-				panic("math/big: buffer too small to fit value")
-			}
-			d >>= 8
-		}
-	}
-
-	if i < 0 {
-		i = 0
-	}
-	for i < len(buf) && buf[i] == 0 {
-		i++
-	}
-
-	return
-}
-
-// bigEndianWord returns the contents of buf interpreted as a big-endian encoded Word value.
-func bigEndianWord(buf []byte) Word {
-	if _W == 64 {
-		return Word(binary.BigEndian.Uint64(buf))
-	}
-	return Word(binary.BigEndian.Uint32(buf))
-}
-
-// setBytes interprets buf as the bytes of a big-endian unsigned
-// integer, sets z to that value, and returns z.
-func (z nat) setBytes(buf []byte) nat {
-	z = z.make((len(buf) + _S - 1) / _S)
-
-	i := len(buf)
-	for k := 0; i >= _S; k++ {
-		z[k] = bigEndianWord(buf[i-_S : i])
-		i -= _S
-	}
-	if i > 0 {
-		var d Word
-		for s := uint(0); i > 0; s += 8 {
-			d |= Word(buf[i-1]) << s
-			i--
-		}
-		z[len(z)-1] = d
-	}
-
-	return z.norm()
-}
-
-// sqrt sets z = ⌊√x⌋
-func (z nat) sqrt(x nat) nat {
-	if x.cmp(natOne) <= 0 {
-		return z.set(x)
-	}
-	if alias(z, x) {
-		z = nil
-	}
-
-	// Start with value known to be too large and repeat "z = ⌊(z + ⌊x/z⌋)/2⌋" until it stops getting smaller.
-	// See Brent and Zimmermann, Modern Computer Arithmetic, Algorithm 1.13 (SqrtInt).
-	// https://members.loria.fr/PZimmermann/mca/pub226.html
-	// If x is one less than a perfect square, the sequence oscillates between the correct z and z+1;
-	// otherwise it converges to the correct z and stays there.
-	var z1, z2 nat
-	z1 = z
-	z1 = z1.setUint64(1)
-	z1 = z1.shl(z1, uint(x.bitLen()+1)/2) // must be ≥ √x
-	for n := 0; ; n++ {
-		z2, _ = z2.div(nil, x, z1)
-		z2 = z2.add(z2, z1)
-		z2 = z2.shr(z2, 1)
-		if z2.cmp(z1) >= 0 {
-			// z1 is answer.
-			// Figure out whether z1 or z2 is currently aliased to z by looking at loop count.
-			if n&1 == 0 {
-				return z1
-			}
-			return z.set(z1)
-		}
-		z1, z2 = z2, z1
-	}
-}
diff --git a/contrib/go/_std_1.18/src/math/big/natconv.go b/contrib/go/_std_1.18/src/math/big/natconv.go
deleted file mode 100644
index 42d1cccf6f..0000000000
--- a/contrib/go/_std_1.18/src/math/big/natconv.go
+++ /dev/null
@@ -1,512 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file implements nat-to-string conversion functions.
-
-package big
-
-import (
-	"errors"
-	"fmt"
-	"io"
-	"math"
-	"math/bits"
-	"sync"
-)
-
-const digits = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
-
-// Note: MaxBase = len(digits), but it must remain an untyped rune constant
-//       for API compatibility.
-
-// MaxBase is the largest number base accepted for string conversions.
-const MaxBase = 10 + ('z' - 'a' + 1) + ('Z' - 'A' + 1)
-const maxBaseSmall = 10 + ('z' - 'a' + 1)
-
-// maxPow returns (b**n, n) such that b**n is the largest power b**n <= _M.
-// For instance maxPow(10) == (1e19, 19) for 19 decimal digits in a 64bit Word.
-// In other words, at most n digits in base b fit into a Word.
-// TODO(gri) replace this with a table, generated at build time.
-func maxPow(b Word) (p Word, n int) {
-	p, n = b, 1 // assuming b <= _M
-	for max := _M / b; p <= max; {
-		// p == b**n && p <= max
-		p *= b
-		n++
-	}
-	// p == b**n && p <= _M
-	return
-}
-
-// pow returns x**n for n > 0, and 1 otherwise.
-func pow(x Word, n int) (p Word) {
-	// n == sum of bi * 2**i, for 0 <= i < imax, and bi is 0 or 1
-	// thus x**n == product of x**(2**i) for all i where bi == 1
-	// (Russian Peasant Method for exponentiation)
-	p = 1
-	for n > 0 {
-		if n&1 != 0 {
-			p *= x
-		}
-		x *= x
-		n >>= 1
-	}
-	return
-}
-
-// scan errors
-var (
-	errNoDigits = errors.New("number has no digits")
-	errInvalSep = errors.New("'_' must separate successive digits")
-)
-
-// scan scans the number corresponding to the longest possible prefix
-// from r representing an unsigned number in a given conversion base.
-// scan returns the corresponding natural number res, the actual base b,
-// a digit count, and a read or syntax error err, if any.
-//
-// For base 0, an underscore character ``_'' may appear between a base
-// prefix and an adjacent digit, and between successive digits; such
-// underscores do not change the value of the number, or the returned
-// digit count. Incorrect placement of underscores is reported as an
-// error if there are no other errors. If base != 0, underscores are
-// not recognized and thus terminate scanning like any other character
-// that is not a valid radix point or digit.
-//
-//     number    = mantissa | prefix pmantissa .
-//     prefix    = "0" [ "b" | "B" | "o" | "O" | "x" | "X" ] .
-//     mantissa  = digits "." [ digits ] | digits | "." digits .
-//     pmantissa = [ "_" ] digits "." [ digits ] | [ "_" ] digits | "." digits .
-//     digits    = digit { [ "_" ] digit } .
-//     digit     = "0" ... "9" | "a" ... "z" | "A" ... "Z" .
-//
-// Unless fracOk is set, the base argument must be 0 or a value between
-// 2 and MaxBase. If fracOk is set, the base argument must be one of
-// 0, 2, 8, 10, or 16. Providing an invalid base argument leads to a run-
-// time panic.
-//
-// For base 0, the number prefix determines the actual base: A prefix of
-// ``0b'' or ``0B'' selects base 2, ``0o'' or ``0O'' selects base 8, and
-// ``0x'' or ``0X'' selects base 16. If fracOk is false, a ``0'' prefix
-// (immediately followed by digits) selects base 8 as well. Otherwise,
-// the selected base is 10 and no prefix is accepted.
-//
-// If fracOk is set, a period followed by a fractional part is permitted.
-// The result value is computed as if there were no period present; and
-// the count value is used to determine the fractional part.
-//
-// For bases <= 36, lower and upper case letters are considered the same:
-// The letters 'a' to 'z' and 'A' to 'Z' represent digit values 10 to 35.
-// For bases > 36, the upper case letters 'A' to 'Z' represent the digit
-// values 36 to 61.
-//
-// A result digit count > 0 corresponds to the number of (non-prefix) digits
-// parsed. A digit count <= 0 indicates the presence of a period (if fracOk
-// is set, only), and -count is the number of fractional digits found.
-// In this case, the actual value of the scanned number is res * b**count.
-//
-func (z nat) scan(r io.ByteScanner, base int, fracOk bool) (res nat, b, count int, err error) {
-	// reject invalid bases
-	baseOk := base == 0 ||
-		!fracOk && 2 <= base && base <= MaxBase ||
-		fracOk && (base == 2 || base == 8 || base == 10 || base == 16)
-	if !baseOk {
-		panic(fmt.Sprintf("invalid number base %d", base))
-	}
-
-	// prev encodes the previously seen char: it is one
-	// of '_', '0' (a digit), or '.' (anything else). A
-	// valid separator '_' may only occur after a digit
-	// and if base == 0.
-	prev := '.'
-	invalSep := false
-
-	// one char look-ahead
-	ch, err := r.ReadByte()
-
-	// determine actual base
-	b, prefix := base, 0
-	if base == 0 {
-		// actual base is 10 unless there's a base prefix
-		b = 10
-		if err == nil && ch == '0' {
-			prev = '0'
-			count = 1
-			ch, err = r.ReadByte()
-			if err == nil {
-				// possibly one of 0b, 0B, 0o, 0O, 0x, 0X
-				switch ch {
-				case 'b', 'B':
-					b, prefix = 2, 'b'
-				case 'o', 'O':
-					b, prefix = 8, 'o'
-				case 'x', 'X':
-					b, prefix = 16, 'x'
-				default:
-					if !fracOk {
-						b, prefix = 8, '0'
-					}
-				}
-				if prefix != 0 {
-					count = 0 // prefix is not counted
-					if prefix != '0' {
-						ch, err = r.ReadByte()
-					}
-				}
-			}
-		}
-	}
-
-	// convert string
-	// Algorithm: Collect digits in groups of at most n digits in di
-	// and then use mulAddWW for every such group to add them to the
-	// result.
-	z = z[:0]
-	b1 := Word(b)
-	bn, n := maxPow(b1) // at most n digits in base b1 fit into Word
-	di := Word(0)       // 0 <= di < b1**i < bn
-	i := 0              // 0 <= i < n
-	dp := -1            // position of decimal point
-	for err == nil {
-		if ch == '.' && fracOk {
-			fracOk = false
-			if prev == '_' {
-				invalSep = true
-			}
-			prev = '.'
-			dp = count
-		} else if ch == '_' && base == 0 {
-			if prev != '0' {
-				invalSep = true
-			}
-			prev = '_'
-		} else {
-			// convert rune into digit value d1
-			var d1 Word
-			switch {
-			case '0' <= ch && ch <= '9':
-				d1 = Word(ch - '0')
-			case 'a' <= ch && ch <= 'z':
-				d1 = Word(ch - 'a' + 10)
-			case 'A' <= ch && ch <= 'Z':
-				if b <= maxBaseSmall {
-					d1 = Word(ch - 'A' + 10)
-				} else {
-					d1 = Word(ch - 'A' + maxBaseSmall)
-				}
-			default:
-				d1 = MaxBase + 1
-			}
-			if d1 >= b1 {
-				r.UnreadByte() // ch does not belong to number anymore
-				break
-			}
-			prev = '0'
-			count++
-
-			// collect d1 in di
-			di = di*b1 + d1
-			i++
-
-			// if di is "full", add it to the result
-			if i == n {
-				z = z.mulAddWW(z, bn, di)
-				di = 0
-				i = 0
-			}
-		}
-
-		ch, err = r.ReadByte()
-	}
-
-	if err == io.EOF {
-		err = nil
-	}
-
-	// other errors take precedence over invalid separators
-	if err == nil && (invalSep || prev == '_') {
-		err = errInvalSep
-	}
-
-	if count == 0 {
-		// no digits found
-		if prefix == '0' {
-			// there was only the octal prefix 0 (possibly followed by separators and digits > 7);
-			// interpret as decimal 0
-			return z[:0], 10, 1, err
-		}
-		err = errNoDigits // fall through; result will be 0
-	}
-
-	// add remaining digits to result
-	if i > 0 {
-		z = z.mulAddWW(z, pow(b1, i), di)
-	}
-	res = z.norm()
-
-	// adjust count for fraction, if any
-	if dp >= 0 {
-		// 0 <= dp <= count
-		count = dp - count
-	}
-
-	return
-}
-
-// utoa converts x to an ASCII representation in the given base;
-// base must be between 2 and MaxBase, inclusive.
-func (x nat) utoa(base int) []byte {
-	return x.itoa(false, base)
-}
-
-// itoa is like utoa but it prepends a '-' if neg && x != 0.
-func (x nat) itoa(neg bool, base int) []byte {
-	if base < 2 || base > MaxBase {
-		panic("invalid base")
-	}
-
-	// x == 0
-	if len(x) == 0 {
-		return []byte("0")
-	}
-	// len(x) > 0
-
-	// allocate buffer for conversion
-	i := int(float64(x.bitLen())/math.Log2(float64(base))) + 1 // off by 1 at most
-	if neg {
-		i++
-	}
-	s := make([]byte, i)
-
-	// convert power of two and non power of two bases separately
-	if b := Word(base); b == b&-b {
-		// shift is base b digit size in bits
-		shift := uint(bits.TrailingZeros(uint(b))) // shift > 0 because b >= 2
-		mask := Word(1<<shift - 1)
-		w := x[0]         // current word
-		nbits := uint(_W) // number of unprocessed bits in w
-
-		// convert less-significant words (include leading zeros)
-		for k := 1; k < len(x); k++ {
-			// convert full digits
-			for nbits >= shift {
-				i--
-				s[i] = digits[w&mask]
-				w >>= shift
-				nbits -= shift
-			}
-
-			// convert any partial leading digit and advance to next word
-			if nbits == 0 {
-				// no partial digit remaining, just advance
-				w = x[k]
-				nbits = _W
-			} else {
-				// partial digit in current word w (== x[k-1]) and next word x[k]
-				w |= x[k] << nbits
-				i--
-				s[i] = digits[w&mask]
-
-				// advance
-				w = x[k] >> (shift - nbits)
-				nbits = _W - (shift - nbits)
-			}
-		}
-
-		// convert digits of most-significant word w (omit leading zeros)
-		for w != 0 {
-			i--
-			s[i] = digits[w&mask]
-			w >>= shift
-		}
-
-	} else {
-		bb, ndigits := maxPow(b)
-
-		// construct table of successive squares of bb*leafSize to use in subdivisions
-		// result (table != nil) <=> (len(x) > leafSize > 0)
-		table := divisors(len(x), b, ndigits, bb)
-
-		// preserve x, create local copy for use by convertWords
-		q := nat(nil).set(x)
-
-		// convert q to string s in base b
-		q.convertWords(s, b, ndigits, bb, table)
-
-		// strip leading zeros
-		// (x != 0; thus s must contain at least one non-zero digit
-		// and the loop will terminate)
-		i = 0
-		for s[i] == '0' {
-			i++
-		}
-	}
-
-	if neg {
-		i--
-		s[i] = '-'
-	}
-
-	return s[i:]
-}
-
-// Convert words of q to base b digits in s. If q is large, it is recursively "split in half"
-// by nat/nat division using tabulated divisors. Otherwise, it is converted iteratively using
-// repeated nat/Word division.
-//
-// The iterative method processes n Words by n divW() calls, each of which visits every Word in the
-// incrementally shortened q for a total of n + (n-1) + (n-2) ... + 2 + 1, or n(n+1)/2 divW()'s.
-// Recursive conversion divides q by its approximate square root, yielding two parts, each half
-// the size of q. Using the iterative method on both halves means 2 * (n/2)(n/2 + 1)/2 divW()'s
-// plus the expensive long div(). Asymptotically, the ratio is favorable at 1/2 the divW()'s, and
-// is made better by splitting the subblocks recursively. Best is to split blocks until one more
-// split would take longer (because of the nat/nat div()) than the twice as many divW()'s of the
-// iterative approach. This threshold is represented by leafSize. Benchmarking of leafSize in the
-// range 2..64 shows that values of 8 and 16 work well, with a 4x speedup at medium lengths and
-// ~30x for 20000 digits. Use nat_test.go's BenchmarkLeafSize tests to optimize leafSize for
-// specific hardware.
-//
-func (q nat) convertWords(s []byte, b Word, ndigits int, bb Word, table []divisor) {
-	// split larger blocks recursively
-	if table != nil {
-		// len(q) > leafSize > 0
-		var r nat
-		index := len(table) - 1
-		for len(q) > leafSize {
-			// find divisor close to sqrt(q) if possible, but in any case < q
-			maxLength := q.bitLen()     // ~= log2 q, or at of least largest possible q of this bit length
-			minLength := maxLength >> 1 // ~= log2 sqrt(q)
-			for index > 0 && table[index-1].nbits > minLength {
-				index-- // desired
-			}
-			if table[index].nbits >= maxLength && table[index].bbb.cmp(q) >= 0 {
-				index--
-				if index < 0 {
-					panic("internal inconsistency")
-				}
-			}
-
-			// split q into the two digit number (q'*bbb + r) to form independent subblocks
-			q, r = q.div(r, q, table[index].bbb)
-
-			// convert subblocks and collect results in s[:h] and s[h:]
-			h := len(s) - table[index].ndigits
-			r.convertWords(s[h:], b, ndigits, bb, table[0:index])
-			s = s[:h] // == q.convertWords(s, b, ndigits, bb, table[0:index+1])
-		}
-	}
-
-	// having split any large blocks now process the remaining (small) block iteratively
-	i := len(s)
-	var r Word
-	if b == 10 {
-		// hard-coding for 10 here speeds this up by 1.25x (allows for / and % by constants)
-		for len(q) > 0 {
-			// extract least significant, base bb "digit"
-			q, r = q.divW(q, bb)
-			for j := 0; j < ndigits && i > 0; j++ {
-				i--
-				// avoid % computation since r%10 == r - int(r/10)*10;
-				// this appears to be faster for BenchmarkString10000Base10
-				// and smaller strings (but a bit slower for larger ones)
-				t := r / 10
-				s[i] = '0' + byte(r-t*10)
-				r = t
-			}
-		}
-	} else {
-		for len(q) > 0 {
-			// extract least significant, base bb "digit"
-			q, r = q.divW(q, bb)
-			for j := 0; j < ndigits && i > 0; j++ {
-				i--
-				s[i] = digits[r%b]
-				r /= b
-			}
-		}
-	}
-
-	// prepend high-order zeros
-	for i > 0 { // while need more leading zeros
-		i--
-		s[i] = '0'
-	}
-}
-
-// Split blocks greater than leafSize Words (or set to 0 to disable recursive conversion)
-// Benchmark and configure leafSize using: go test -bench="Leaf"
-//   8 and 16 effective on 3.0 GHz Xeon "Clovertown" CPU (128 byte cache lines)
-//   8 and 16 effective on 2.66 GHz Core 2 Duo "Penryn" CPU
-var leafSize int = 8 // number of Word-size binary values treat as a monolithic block
-
-type divisor struct {
-	bbb     nat // divisor
-	nbits   int // bit length of divisor (discounting leading zeros) ~= log2(bbb)
-	ndigits int // digit length of divisor in terms of output base digits
-}
-
-var cacheBase10 struct {
-	sync.Mutex
-	table [64]divisor // cached divisors for base 10
-}
-
-// expWW computes x**y
-func (z nat) expWW(x, y Word) nat {
-	return z.expNN(nat(nil).setWord(x), nat(nil).setWord(y), nil)
-}
-
-// construct table of powers of bb*leafSize to use in subdivisions
-func divisors(m int, b Word, ndigits int, bb Word) []divisor {
-	// only compute table when recursive conversion is enabled and x is large
-	if leafSize == 0 || m <= leafSize {
-		return nil
-	}
-
-	// determine k where (bb**leafSize)**(2**k) >= sqrt(x)
-	k := 1
-	for words := leafSize; words < m>>1 && k < len(cacheBase10.table); words <<= 1 {
-		k++
-	}
-
-	// reuse and extend existing table of divisors or create new table as appropriate
-	var table []divisor // for b == 10, table overlaps with cacheBase10.table
-	if b == 10 {
-		cacheBase10.Lock()
-		table = cacheBase10.table[0:k] // reuse old table for this conversion
-	} else {
-		table = make([]divisor, k) // create new table for this conversion
-	}
-
-	// extend table
-	if table[k-1].ndigits == 0 {
-		// add new entries as needed
-		var larger nat
-		for i := 0; i < k; i++ {
-			if table[i].ndigits == 0 {
-				if i == 0 {
-					table[0].bbb = nat(nil).expWW(bb, Word(leafSize))
-					table[0].ndigits = ndigits * leafSize
-				} else {
-					table[i].bbb = nat(nil).sqr(table[i-1].bbb)
-					table[i].ndigits = 2 * table[i-1].ndigits
-				}
-
-				// optimization: exploit aggregated extra bits in macro blocks
-				larger = nat(nil).set(table[i].bbb)
-				for mulAddVWW(larger, larger, b, 0) == 0 {
-					table[i].bbb = table[i].bbb.set(larger)
-					table[i].ndigits++
-				}
-
-				table[i].nbits = table[i].bbb.bitLen()
-			}
-		}
-	}
-
-	if b == 10 {
-		cacheBase10.Unlock()
-	}
-
-	return table
-}
diff --git a/contrib/go/_std_1.18/src/math/big/rat.go b/contrib/go/_std_1.18/src/math/big/rat.go
deleted file mode 100644
index 731a979ff7..0000000000
--- a/contrib/go/_std_1.18/src/math/big/rat.go
+++ /dev/null
@@ -1,544 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file implements multi-precision rational numbers.
-
-package big
-
-import (
-	"fmt"
-	"math"
-)
-
-// A Rat represents a quotient a/b of arbitrary precision.
-// The zero value for a Rat represents the value 0.
-//
-// Operations always take pointer arguments (*Rat) rather
-// than Rat values, and each unique Rat value requires
-// its own unique *Rat pointer. To "copy" a Rat value,
-// an existing (or newly allocated) Rat must be set to
-// a new value using the Rat.Set method; shallow copies
-// of Rats are not supported and may lead to errors.
-type Rat struct {
-	// To make zero values for Rat work w/o initialization,
-	// a zero value of b (len(b) == 0) acts like b == 1. At
-	// the earliest opportunity (when an assignment to the Rat
-	// is made), such uninitialized denominators are set to 1.
-	// a.neg determines the sign of the Rat, b.neg is ignored.
-	a, b Int
-}
-
-// NewRat creates a new Rat with numerator a and denominator b.
-func NewRat(a, b int64) *Rat {
-	return new(Rat).SetFrac64(a, b)
-}
-
-// SetFloat64 sets z to exactly f and returns z.
-// If f is not finite, SetFloat returns nil.
-func (z *Rat) SetFloat64(f float64) *Rat {
-	const expMask = 1<<11 - 1
-	bits := math.Float64bits(f)
-	mantissa := bits & (1<<52 - 1)
-	exp := int((bits >> 52) & expMask)
-	switch exp {
-	case expMask: // non-finite
-		return nil
-	case 0: // denormal
-		exp -= 1022
-	default: // normal
-		mantissa |= 1 << 52
-		exp -= 1023
-	}
-
-	shift := 52 - exp
-
-	// Optimization (?): partially pre-normalise.
-	for mantissa&1 == 0 && shift > 0 {
-		mantissa >>= 1
-		shift--
-	}
-
-	z.a.SetUint64(mantissa)
-	z.a.neg = f < 0
-	z.b.Set(intOne)
-	if shift > 0 {
-		z.b.Lsh(&z.b, uint(shift))
-	} else {
-		z.a.Lsh(&z.a, uint(-shift))
-	}
-	return z.norm()
-}
-
-// quotToFloat32 returns the non-negative float32 value
-// nearest to the quotient a/b, using round-to-even in
-// halfway cases. It does not mutate its arguments.
-// Preconditions: b is non-zero; a and b have no common factors.
-func quotToFloat32(a, b nat) (f float32, exact bool) {
-	const (
-		// float size in bits
-		Fsize = 32
-
-		// mantissa
-		Msize  = 23
-		Msize1 = Msize + 1 // incl. implicit 1
-		Msize2 = Msize1 + 1
-
-		// exponent
-		Esize = Fsize - Msize1
-		Ebias = 1<<(Esize-1) - 1
-		Emin  = 1 - Ebias
-		Emax  = Ebias
-	)
-
-	// TODO(adonovan): specialize common degenerate cases: 1.0, integers.
-	alen := a.bitLen()
-	if alen == 0 {
-		return 0, true
-	}
-	blen := b.bitLen()
-	if blen == 0 {
-		panic("division by zero")
-	}
-
-	// 1. Left-shift A or B such that quotient A/B is in [1<<Msize1, 1<<(Msize2+1)
-	// (Msize2 bits if A < B when they are left-aligned, Msize2+1 bits if A >= B).
-	// This is 2 or 3 more than the float32 mantissa field width of Msize:
-	// - the optional extra bit is shifted away in step 3 below.
-	// - the high-order 1 is omitted in "normal" representation;
-	// - the low-order 1 will be used during rounding then discarded.
-	exp := alen - blen
-	var a2, b2 nat
-	a2 = a2.set(a)
-	b2 = b2.set(b)
-	if shift := Msize2 - exp; shift > 0 {
-		a2 = a2.shl(a2, uint(shift))
-	} else if shift < 0 {
-		b2 = b2.shl(b2, uint(-shift))
-	}
-
-	// 2. Compute quotient and remainder (q, r).  NB: due to the
-	// extra shift, the low-order bit of q is logically the
-	// high-order bit of r.
-	var q nat
-	q, r := q.div(a2, a2, b2) // (recycle a2)
-	mantissa := low32(q)
-	haveRem := len(r) > 0 // mantissa&1 && !haveRem => remainder is exactly half
-
-	// 3. If quotient didn't fit in Msize2 bits, redo division by b2<<1
-	// (in effect---we accomplish this incrementally).
-	if mantissa>>Msize2 == 1 {
-		if mantissa&1 == 1 {
-			haveRem = true
-		}
-		mantissa >>= 1
-		exp++
-	}
-	if mantissa>>Msize1 != 1 {
-		panic(fmt.Sprintf("expected exactly %d bits of result", Msize2))
-	}
-
-	// 4. Rounding.
-	if Emin-Msize <= exp && exp <= Emin {
-		// Denormal case; lose 'shift' bits of precision.
-		shift := uint(Emin - (exp - 1)) // [1..Esize1)
-		lostbits := mantissa & (1<<shift - 1)
-		haveRem = haveRem || lostbits != 0
-		mantissa >>= shift
-		exp = 2 - Ebias // == exp + shift
-	}
-	// Round q using round-half-to-even.
-	exact = !haveRem
-	if mantissa&1 != 0 {
-		exact = false
-		if haveRem || mantissa&2 != 0 {
-			if mantissa++; mantissa >= 1<<Msize2 {
-				// Complete rollover 11...1 => 100...0, so shift is safe
-				mantissa >>= 1
-				exp++
-			}
-		}
-	}
-	mantissa >>= 1 // discard rounding bit.  Mantissa now scaled by 1<<Msize1.
-
-	f = float32(math.Ldexp(float64(mantissa), exp-Msize1))
-	if math.IsInf(float64(f), 0) {
-		exact = false
-	}
-	return
-}
-
-// quotToFloat64 returns the non-negative float64 value
-// nearest to the quotient a/b, using round-to-even in
-// halfway cases. It does not mutate its arguments.
-// Preconditions: b is non-zero; a and b have no common factors.
-func quotToFloat64(a, b nat) (f float64, exact bool) {
-	const (
-		// float size in bits
-		Fsize = 64
-
-		// mantissa
-		Msize  = 52
-		Msize1 = Msize + 1 // incl. implicit 1
-		Msize2 = Msize1 + 1
-
-		// exponent
-		Esize = Fsize - Msize1
-		Ebias = 1<<(Esize-1) - 1
-		Emin  = 1 - Ebias
-		Emax  = Ebias
-	)
-
-	// TODO(adonovan): specialize common degenerate cases: 1.0, integers.
-	alen := a.bitLen()
-	if alen == 0 {
-		return 0, true
-	}
-	blen := b.bitLen()
-	if blen == 0 {
-		panic("division by zero")
-	}
-
-	// 1. Left-shift A or B such that quotient A/B is in [1<<Msize1, 1<<(Msize2+1)
-	// (Msize2 bits if A < B when they are left-aligned, Msize2+1 bits if A >= B).
-	// This is 2 or 3 more than the float64 mantissa field width of Msize:
-	// - the optional extra bit is shifted away in step 3 below.
-	// - the high-order 1 is omitted in "normal" representation;
-	// - the low-order 1 will be used during rounding then discarded.
-	exp := alen - blen
-	var a2, b2 nat
-	a2 = a2.set(a)
-	b2 = b2.set(b)
-	if shift := Msize2 - exp; shift > 0 {
-		a2 = a2.shl(a2, uint(shift))
-	} else if shift < 0 {
-		b2 = b2.shl(b2, uint(-shift))
-	}
-
-	// 2. Compute quotient and remainder (q, r).  NB: due to the
-	// extra shift, the low-order bit of q is logically the
-	// high-order bit of r.
-	var q nat
-	q, r := q.div(a2, a2, b2) // (recycle a2)
-	mantissa := low64(q)
-	haveRem := len(r) > 0 // mantissa&1 && !haveRem => remainder is exactly half
-
-	// 3. If quotient didn't fit in Msize2 bits, redo division by b2<<1
-	// (in effect---we accomplish this incrementally).
-	if mantissa>>Msize2 == 1 {
-		if mantissa&1 == 1 {
-			haveRem = true
-		}
-		mantissa >>= 1
-		exp++
-	}
-	if mantissa>>Msize1 != 1 {
-		panic(fmt.Sprintf("expected exactly %d bits of result", Msize2))
-	}
-
-	// 4. Rounding.
-	if Emin-Msize <= exp && exp <= Emin {
-		// Denormal case; lose 'shift' bits of precision.
-		shift := uint(Emin - (exp - 1)) // [1..Esize1)
-		lostbits := mantissa & (1<<shift - 1)
-		haveRem = haveRem || lostbits != 0
-		mantissa >>= shift
-		exp = 2 - Ebias // == exp + shift
-	}
-	// Round q using round-half-to-even.
-	exact = !haveRem
-	if mantissa&1 != 0 {
-		exact = false
-		if haveRem || mantissa&2 != 0 {
-			if mantissa++; mantissa >= 1<<Msize2 {
-				// Complete rollover 11...1 => 100...0, so shift is safe
-				mantissa >>= 1
-				exp++
-			}
-		}
-	}
-	mantissa >>= 1 // discard rounding bit.  Mantissa now scaled by 1<<Msize1.
-
-	f = math.Ldexp(float64(mantissa), exp-Msize1)
-	if math.IsInf(f, 0) {
-		exact = false
-	}
-	return
-}
-
-// Float32 returns the nearest float32 value for x and a bool indicating
-// whether f represents x exactly. If the magnitude of x is too large to
-// be represented by a float32, f is an infinity and exact is false.
-// The sign of f always matches the sign of x, even if f == 0.
-func (x *Rat) Float32() (f float32, exact bool) {
-	b := x.b.abs
-	if len(b) == 0 {
-		b = natOne
-	}
-	f, exact = quotToFloat32(x.a.abs, b)
-	if x.a.neg {
-		f = -f
-	}
-	return
-}
-
-// Float64 returns the nearest float64 value for x and a bool indicating
-// whether f represents x exactly. If the magnitude of x is too large to
-// be represented by a float64, f is an infinity and exact is false.
-// The sign of f always matches the sign of x, even if f == 0.
-func (x *Rat) Float64() (f float64, exact bool) {
-	b := x.b.abs
-	if len(b) == 0 {
-		b = natOne
-	}
-	f, exact = quotToFloat64(x.a.abs, b)
-	if x.a.neg {
-		f = -f
-	}
-	return
-}
-
-// SetFrac sets z to a/b and returns z.
-// If b == 0, SetFrac panics.
-func (z *Rat) SetFrac(a, b *Int) *Rat {
-	z.a.neg = a.neg != b.neg
-	babs := b.abs
-	if len(babs) == 0 {
-		panic("division by zero")
-	}
-	if &z.a == b || alias(z.a.abs, babs) {
-		babs = nat(nil).set(babs) // make a copy
-	}
-	z.a.abs = z.a.abs.set(a.abs)
-	z.b.abs = z.b.abs.set(babs)
-	return z.norm()
-}
-
-// SetFrac64 sets z to a/b and returns z.
-// If b == 0, SetFrac64 panics.
-func (z *Rat) SetFrac64(a, b int64) *Rat {
-	if b == 0 {
-		panic("division by zero")
-	}
-	z.a.SetInt64(a)
-	if b < 0 {
-		b = -b
-		z.a.neg = !z.a.neg
-	}
-	z.b.abs = z.b.abs.setUint64(uint64(b))
-	return z.norm()
-}
-
-// SetInt sets z to x (by making a copy of x) and returns z.
-func (z *Rat) SetInt(x *Int) *Rat {
-	z.a.Set(x)
-	z.b.abs = z.b.abs.setWord(1)
-	return z
-}
-
-// SetInt64 sets z to x and returns z.
-func (z *Rat) SetInt64(x int64) *Rat {
-	z.a.SetInt64(x)
-	z.b.abs = z.b.abs.setWord(1)
-	return z
-}
-
-// SetUint64 sets z to x and returns z.
-func (z *Rat) SetUint64(x uint64) *Rat {
-	z.a.SetUint64(x)
-	z.b.abs = z.b.abs.setWord(1)
-	return z
-}
-
-// Set sets z to x (by making a copy of x) and returns z.
-func (z *Rat) Set(x *Rat) *Rat {
-	if z != x {
-		z.a.Set(&x.a)
-		z.b.Set(&x.b)
-	}
-	if len(z.b.abs) == 0 {
-		z.b.abs = z.b.abs.setWord(1)
-	}
-	return z
-}
-
-// Abs sets z to |x| (the absolute value of x) and returns z.
-func (z *Rat) Abs(x *Rat) *Rat {
-	z.Set(x)
-	z.a.neg = false
-	return z
-}
-
-// Neg sets z to -x and returns z.
-func (z *Rat) Neg(x *Rat) *Rat {
-	z.Set(x)
-	z.a.neg = len(z.a.abs) > 0 && !z.a.neg // 0 has no sign
-	return z
-}
-
-// Inv sets z to 1/x and returns z.
-// If x == 0, Inv panics.
-func (z *Rat) Inv(x *Rat) *Rat {
-	if len(x.a.abs) == 0 {
-		panic("division by zero")
-	}
-	z.Set(x)
-	z.a.abs, z.b.abs = z.b.abs, z.a.abs
-	return z
-}
-
-// Sign returns:
-//
-//	-1 if x <  0
-//	 0 if x == 0
-//	+1 if x >  0
-//
-func (x *Rat) Sign() int {
-	return x.a.Sign()
-}
-
-// IsInt reports whether the denominator of x is 1.
-func (x *Rat) IsInt() bool {
-	return len(x.b.abs) == 0 || x.b.abs.cmp(natOne) == 0
-}
-
-// Num returns the numerator of x; it may be <= 0.
-// The result is a reference to x's numerator; it
-// may change if a new value is assigned to x, and vice versa.
-// The sign of the numerator corresponds to the sign of x.
-func (x *Rat) Num() *Int {
-	return &x.a
-}
-
-// Denom returns the denominator of x; it is always > 0.
-// The result is a reference to x's denominator, unless
-// x is an uninitialized (zero value) Rat, in which case
-// the result is a new Int of value 1. (To initialize x,
-// any operation that sets x will do, including x.Set(x).)
-// If the result is a reference to x's denominator it
-// may change if a new value is assigned to x, and vice versa.
-func (x *Rat) Denom() *Int {
-	// Note that x.b.neg is guaranteed false.
-	if len(x.b.abs) == 0 {
-		// Note: If this proves problematic, we could
-		//       panic instead and require the Rat to
-		//       be explicitly initialized.
-		return &Int{abs: nat{1}}
-	}
-	return &x.b
-}
-
-func (z *Rat) norm() *Rat {
-	switch {
-	case len(z.a.abs) == 0:
-		// z == 0; normalize sign and denominator
-		z.a.neg = false
-		fallthrough
-	case len(z.b.abs) == 0:
-		// z is integer; normalize denominator
-		z.b.abs = z.b.abs.setWord(1)
-	default:
-		// z is fraction; normalize numerator and denominator
-		neg := z.a.neg
-		z.a.neg = false
-		z.b.neg = false
-		if f := NewInt(0).lehmerGCD(nil, nil, &z.a, &z.b); f.Cmp(intOne) != 0 {
-			z.a.abs, _ = z.a.abs.div(nil, z.a.abs, f.abs)
-			z.b.abs, _ = z.b.abs.div(nil, z.b.abs, f.abs)
-		}
-		z.a.neg = neg
-	}
-	return z
-}
-
-// mulDenom sets z to the denominator product x*y (by taking into
-// account that 0 values for x or y must be interpreted as 1) and
-// returns z.
-func mulDenom(z, x, y nat) nat {
-	switch {
-	case len(x) == 0 && len(y) == 0:
-		return z.setWord(1)
-	case len(x) == 0:
-		return z.set(y)
-	case len(y) == 0:
-		return z.set(x)
-	}
-	return z.mul(x, y)
-}
-
-// scaleDenom sets z to the product x*f.
-// If f == 0 (zero value of denominator), z is set to (a copy of) x.
-func (z *Int) scaleDenom(x *Int, f nat) {
-	if len(f) == 0 {
-		z.Set(x)
-		return
-	}
-	z.abs = z.abs.mul(x.abs, f)
-	z.neg = x.neg
-}
-
-// Cmp compares x and y and returns:
-//
-//   -1 if x <  y
-//    0 if x == y
-//   +1 if x >  y
-//
-func (x *Rat) Cmp(y *Rat) int {
-	var a, b Int
-	a.scaleDenom(&x.a, y.b.abs)
-	b.scaleDenom(&y.a, x.b.abs)
-	return a.Cmp(&b)
-}
-
-// Add sets z to the sum x+y and returns z.
-func (z *Rat) Add(x, y *Rat) *Rat {
-	var a1, a2 Int
-	a1.scaleDenom(&x.a, y.b.abs)
-	a2.scaleDenom(&y.a, x.b.abs)
-	z.a.Add(&a1, &a2)
-	z.b.abs = mulDenom(z.b.abs, x.b.abs, y.b.abs)
-	return z.norm()
-}
-
-// Sub sets z to the difference x-y and returns z.
-func (z *Rat) Sub(x, y *Rat) *Rat {
-	var a1, a2 Int
-	a1.scaleDenom(&x.a, y.b.abs)
-	a2.scaleDenom(&y.a, x.b.abs)
-	z.a.Sub(&a1, &a2)
-	z.b.abs = mulDenom(z.b.abs, x.b.abs, y.b.abs)
-	return z.norm()
-}
-
-// Mul sets z to the product x*y and returns z.
-func (z *Rat) Mul(x, y *Rat) *Rat {
-	if x == y {
-		// a squared Rat is positive and can't be reduced (no need to call norm())
-		z.a.neg = false
-		z.a.abs = z.a.abs.sqr(x.a.abs)
-		if len(x.b.abs) == 0 {
-			z.b.abs = z.b.abs.setWord(1)
-		} else {
-			z.b.abs = z.b.abs.sqr(x.b.abs)
-		}
-		return z
-	}
-	z.a.Mul(&x.a, &y.a)
-	z.b.abs = mulDenom(z.b.abs, x.b.abs, y.b.abs)
-	return z.norm()
-}
-
-// Quo sets z to the quotient x/y and returns z.
-// If y == 0, Quo panics.
-func (z *Rat) Quo(x, y *Rat) *Rat {
-	if len(y.a.abs) == 0 {
-		panic("division by zero")
-	}
-	var a, b Int
-	a.scaleDenom(&x.a, y.b.abs)
-	b.scaleDenom(&y.a, x.b.abs)
-	z.a.abs = a.abs
-	z.b.abs = b.abs
-	z.a.neg = a.neg != b.neg
-	return z.norm()
-}
diff --git a/contrib/go/_std_1.18/src/math/big/ratconv.go b/contrib/go/_std_1.18/src/math/big/ratconv.go
deleted file mode 100644
index 90053a9c81..0000000000
--- a/contrib/go/_std_1.18/src/math/big/ratconv.go
+++ /dev/null
@@ -1,380 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file implements rat-to-string conversion functions.
-
-package big
-
-import (
-	"errors"
-	"fmt"
-	"io"
-	"strconv"
-	"strings"
-)
-
-func ratTok(ch rune) bool {
-	return strings.ContainsRune("+-/0123456789.eE", ch)
-}
-
-var ratZero Rat
-var _ fmt.Scanner = &ratZero // *Rat must implement fmt.Scanner
-
-// Scan is a support routine for fmt.Scanner. It accepts the formats
-// 'e', 'E', 'f', 'F', 'g', 'G', and 'v'. All formats are equivalent.
-func (z *Rat) Scan(s fmt.ScanState, ch rune) error {
-	tok, err := s.Token(true, ratTok)
-	if err != nil {
-		return err
-	}
-	if !strings.ContainsRune("efgEFGv", ch) {
-		return errors.New("Rat.Scan: invalid verb")
-	}
-	if _, ok := z.SetString(string(tok)); !ok {
-		return errors.New("Rat.Scan: invalid syntax")
-	}
-	return nil
-}
-
-// SetString sets z to the value of s and returns z and a boolean indicating
-// success. s can be given as a (possibly signed) fraction "a/b", or as a
-// floating-point number optionally followed by an exponent.
-// If a fraction is provided, both the dividend and the divisor may be a
-// decimal integer or independently use a prefix of ``0b'', ``0'' or ``0o'',
-// or ``0x'' (or their upper-case variants) to denote a binary, octal, or
-// hexadecimal integer, respectively. The divisor may not be signed.
-// If a floating-point number is provided, it may be in decimal form or
-// use any of the same prefixes as above but for ``0'' to denote a non-decimal
-// mantissa. A leading ``0'' is considered a decimal leading 0; it does not
-// indicate octal representation in this case.
-// An optional base-10 ``e'' or base-2 ``p'' (or their upper-case variants)
-// exponent may be provided as well, except for hexadecimal floats which
-// only accept an (optional) ``p'' exponent (because an ``e'' or ``E'' cannot
-// be distinguished from a mantissa digit). If the exponent's absolute value
-// is too large, the operation may fail.
-// The entire string, not just a prefix, must be valid for success. If the
-// operation failed, the value of z is undefined but the returned value is nil.
-func (z *Rat) SetString(s string) (*Rat, bool) {
-	if len(s) == 0 {
-		return nil, false
-	}
-	// len(s) > 0
-
-	// parse fraction a/b, if any
-	if sep := strings.Index(s, "/"); sep >= 0 {
-		if _, ok := z.a.SetString(s[:sep], 0); !ok {
-			return nil, false
-		}
-		r := strings.NewReader(s[sep+1:])
-		var err error
-		if z.b.abs, _, _, err = z.b.abs.scan(r, 0, false); err != nil {
-			return nil, false
-		}
-		// entire string must have been consumed
-		if _, err = r.ReadByte(); err != io.EOF {
-			return nil, false
-		}
-		if len(z.b.abs) == 0 {
-			return nil, false
-		}
-		return z.norm(), true
-	}
-
-	// parse floating-point number
-	r := strings.NewReader(s)
-
-	// sign
-	neg, err := scanSign(r)
-	if err != nil {
-		return nil, false
-	}
-
-	// mantissa
-	var base int
-	var fcount int // fractional digit count; valid if <= 0
-	z.a.abs, base, fcount, err = z.a.abs.scan(r, 0, true)
-	if err != nil {
-		return nil, false
-	}
-
-	// exponent
-	var exp int64
-	var ebase int
-	exp, ebase, err = scanExponent(r, true, true)
-	if err != nil {
-		return nil, false
-	}
-
-	// there should be no unread characters left
-	if _, err = r.ReadByte(); err != io.EOF {
-		return nil, false
-	}
-
-	// special-case 0 (see also issue #16176)
-	if len(z.a.abs) == 0 {
-		return z, true
-	}
-	// len(z.a.abs) > 0
-
-	// The mantissa may have a radix point (fcount <= 0) and there
-	// may be a nonzero exponent exp. The radix point amounts to a
-	// division by base**(-fcount), which equals a multiplication by
-	// base**fcount. An exponent means multiplication by ebase**exp.
-	// Multiplications are commutative, so we can apply them in any
-	// order. We only have powers of 2 and 10, and we split powers
-	// of 10 into the product of the same powers of 2 and 5. This
-	// may reduce the size of shift/multiplication factors or
-	// divisors required to create the final fraction, depending
-	// on the actual floating-point value.
-
-	// determine binary or decimal exponent contribution of radix point
-	var exp2, exp5 int64
-	if fcount < 0 {
-		// The mantissa has a radix point ddd.dddd; and
-		// -fcount is the number of digits to the right
-		// of '.'. Adjust relevant exponent accordingly.
-		d := int64(fcount)
-		switch base {
-		case 10:
-			exp5 = d
-			fallthrough // 10**e == 5**e * 2**e
-		case 2:
-			exp2 = d
-		case 8:
-			exp2 = d * 3 // octal digits are 3 bits each
-		case 16:
-			exp2 = d * 4 // hexadecimal digits are 4 bits each
-		default:
-			panic("unexpected mantissa base")
-		}
-		// fcount consumed - not needed anymore
-	}
-
-	// take actual exponent into account
-	switch ebase {
-	case 10:
-		exp5 += exp
-		fallthrough // see fallthrough above
-	case 2:
-		exp2 += exp
-	default:
-		panic("unexpected exponent base")
-	}
-	// exp consumed - not needed anymore
-
-	// apply exp5 contributions
-	// (start with exp5 so the numbers to multiply are smaller)
-	if exp5 != 0 {
-		n := exp5
-		if n < 0 {
-			n = -n
-			if n < 0 {
-				// This can occur if -n overflows. -(-1 << 63) would become
-				// -1 << 63, which is still negative.
-				return nil, false
-			}
-		}
-		if n > 1e6 {
-			return nil, false // avoid excessively large exponents
-		}
-		pow5 := z.b.abs.expNN(natFive, nat(nil).setWord(Word(n)), nil) // use underlying array of z.b.abs
-		if exp5 > 0 {
-			z.a.abs = z.a.abs.mul(z.a.abs, pow5)
-			z.b.abs = z.b.abs.setWord(1)
-		} else {
-			z.b.abs = pow5
-		}
-	} else {
-		z.b.abs = z.b.abs.setWord(1)
-	}
-
-	// apply exp2 contributions
-	if exp2 < -1e7 || exp2 > 1e7 {
-		return nil, false // avoid excessively large exponents
-	}
-	if exp2 > 0 {
-		z.a.abs = z.a.abs.shl(z.a.abs, uint(exp2))
-	} else if exp2 < 0 {
-		z.b.abs = z.b.abs.shl(z.b.abs, uint(-exp2))
-	}
-
-	z.a.neg = neg && len(z.a.abs) > 0 // 0 has no sign
-
-	return z.norm(), true
-}
-
-// scanExponent scans the longest possible prefix of r representing a base 10
-// (``e'', ``E'') or a base 2 (``p'', ``P'') exponent, if any. It returns the
-// exponent, the exponent base (10 or 2), or a read or syntax error, if any.
-//
-// If sepOk is set, an underscore character ``_'' may appear between successive
-// exponent digits; such underscores do not change the value of the exponent.
-// Incorrect placement of underscores is reported as an error if there are no
-// other errors. If sepOk is not set, underscores are not recognized and thus
-// terminate scanning like any other character that is not a valid digit.
-//
-//	exponent = ( "e" | "E" | "p" | "P" ) [ sign ] digits .
-//	sign     = "+" | "-" .
-//	digits   = digit { [ '_' ] digit } .
-//	digit    = "0" ... "9" .
-//
-// A base 2 exponent is only permitted if base2ok is set.
-func scanExponent(r io.ByteScanner, base2ok, sepOk bool) (exp int64, base int, err error) {
-	// one char look-ahead
-	ch, err := r.ReadByte()
-	if err != nil {
-		if err == io.EOF {
-			err = nil
-		}
-		return 0, 10, err
-	}
-
-	// exponent char
-	switch ch {
-	case 'e', 'E':
-		base = 10
-	case 'p', 'P':
-		if base2ok {
-			base = 2
-			break // ok
-		}
-		fallthrough // binary exponent not permitted
-	default:
-		r.UnreadByte() // ch does not belong to exponent anymore
-		return 0, 10, nil
-	}
-
-	// sign
-	var digits []byte
-	ch, err = r.ReadByte()
-	if err == nil && (ch == '+' || ch == '-') {
-		if ch == '-' {
-			digits = append(digits, '-')
-		}
-		ch, err = r.ReadByte()
-	}
-
-	// prev encodes the previously seen char: it is one
-	// of '_', '0' (a digit), or '.' (anything else). A
-	// valid separator '_' may only occur after a digit.
-	prev := '.'
-	invalSep := false
-
-	// exponent value
-	hasDigits := false
-	for err == nil {
-		if '0' <= ch && ch <= '9' {
-			digits = append(digits, ch)
-			prev = '0'
-			hasDigits = true
-		} else if ch == '_' && sepOk {
-			if prev != '0' {
-				invalSep = true
-			}
-			prev = '_'
-		} else {
-			r.UnreadByte() // ch does not belong to number anymore
-			break
-		}
-		ch, err = r.ReadByte()
-	}
-
-	if err == io.EOF {
-		err = nil
-	}
-	if err == nil && !hasDigits {
-		err = errNoDigits
-	}
-	if err == nil {
-		exp, err = strconv.ParseInt(string(digits), 10, 64)
-	}
-	// other errors take precedence over invalid separators
-	if err == nil && (invalSep || prev == '_') {
-		err = errInvalSep
-	}
-
-	return
-}
-
-// String returns a string representation of x in the form "a/b" (even if b == 1).
-func (x *Rat) String() string {
-	return string(x.marshal())
-}
-
-// marshal implements String returning a slice of bytes
-func (x *Rat) marshal() []byte {
-	var buf []byte
-	buf = x.a.Append(buf, 10)
-	buf = append(buf, '/')
-	if len(x.b.abs) != 0 {
-		buf = x.b.Append(buf, 10)
-	} else {
-		buf = append(buf, '1')
-	}
-	return buf
-}
-
-// RatString returns a string representation of x in the form "a/b" if b != 1,
-// and in the form "a" if b == 1.
-func (x *Rat) RatString() string {
-	if x.IsInt() {
-		return x.a.String()
-	}
-	return x.String()
-}
-
-// FloatString returns a string representation of x in decimal form with prec
-// digits of precision after the radix point. The last digit is rounded to
-// nearest, with halves rounded away from zero.
-func (x *Rat) FloatString(prec int) string {
-	var buf []byte
-
-	if x.IsInt() {
-		buf = x.a.Append(buf, 10)
-		if prec > 0 {
-			buf = append(buf, '.')
-			for i := prec; i > 0; i-- {
-				buf = append(buf, '0')
-			}
-		}
-		return string(buf)
-	}
-	// x.b.abs != 0
-
-	q, r := nat(nil).div(nat(nil), x.a.abs, x.b.abs)
-
-	p := natOne
-	if prec > 0 {
-		p = nat(nil).expNN(natTen, nat(nil).setUint64(uint64(prec)), nil)
-	}
-
-	r = r.mul(r, p)
-	r, r2 := r.div(nat(nil), r, x.b.abs)
-
-	// see if we need to round up
-	r2 = r2.add(r2, r2)
-	if x.b.abs.cmp(r2) <= 0 {
-		r = r.add(r, natOne)
-		if r.cmp(p) >= 0 {
-			q = nat(nil).add(q, natOne)
-			r = nat(nil).sub(r, p)
-		}
-	}
-
-	if x.a.neg {
-		buf = append(buf, '-')
-	}
-	buf = append(buf, q.utoa(10)...) // itoa ignores sign if q == 0
-
-	if prec > 0 {
-		buf = append(buf, '.')
-		rs := r.utoa(10)
-		for i := prec - len(rs); i > 0; i-- {
-			buf = append(buf, '0')
-		}
-		buf = append(buf, rs...)
-	}
-
-	return string(buf)
-}
diff --git a/contrib/go/_std_1.18/src/math/big/ratmarsh.go b/contrib/go/_std_1.18/src/math/big/ratmarsh.go
deleted file mode 100644
index fbc7b6002d..0000000000
--- a/contrib/go/_std_1.18/src/math/big/ratmarsh.go
+++ /dev/null
@@ -1,75 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file implements encoding/decoding of Rats.
-
-package big
-
-import (
-	"encoding/binary"
-	"errors"
-	"fmt"
-)
-
-// Gob codec version. Permits backward-compatible changes to the encoding.
-const ratGobVersion byte = 1
-
-// GobEncode implements the gob.GobEncoder interface.
-func (x *Rat) GobEncode() ([]byte, error) {
-	if x == nil {
-		return nil, nil
-	}
-	buf := make([]byte, 1+4+(len(x.a.abs)+len(x.b.abs))*_S) // extra bytes for version and sign bit (1), and numerator length (4)
-	i := x.b.abs.bytes(buf)
-	j := x.a.abs.bytes(buf[:i])
-	n := i - j
-	if int(uint32(n)) != n {
-		// this should never happen
-		return nil, errors.New("Rat.GobEncode: numerator too large")
-	}
-	binary.BigEndian.PutUint32(buf[j-4:j], uint32(n))
-	j -= 1 + 4
-	b := ratGobVersion << 1 // make space for sign bit
-	if x.a.neg {
-		b |= 1
-	}
-	buf[j] = b
-	return buf[j:], nil
-}
-
-// GobDecode implements the gob.GobDecoder interface.
-func (z *Rat) GobDecode(buf []byte) error {
-	if len(buf) == 0 {
-		// Other side sent a nil or default value.
-		*z = Rat{}
-		return nil
-	}
-	b := buf[0]
-	if b>>1 != ratGobVersion {
-		return fmt.Errorf("Rat.GobDecode: encoding version %d not supported", b>>1)
-	}
-	const j = 1 + 4
-	i := j + binary.BigEndian.Uint32(buf[j-4:j])
-	z.a.neg = b&1 != 0
-	z.a.abs = z.a.abs.setBytes(buf[j:i])
-	z.b.abs = z.b.abs.setBytes(buf[i:])
-	return nil
-}
-
-// MarshalText implements the encoding.TextMarshaler interface.
-func (x *Rat) MarshalText() (text []byte, err error) {
-	if x.IsInt() {
-		return x.a.MarshalText()
-	}
-	return x.marshal(), nil
-}
-
-// UnmarshalText implements the encoding.TextUnmarshaler interface.
-func (z *Rat) UnmarshalText(text []byte) error {
-	// TODO(gri): get rid of the []byte/string conversion
-	if _, ok := z.SetString(string(text)); !ok {
-		return fmt.Errorf("math/big: cannot unmarshal %q into a *big.Rat", text)
-	}
-	return nil
-}
diff --git a/contrib/go/_std_1.18/src/math/big/sqrt.go b/contrib/go/_std_1.18/src/math/big/sqrt.go
deleted file mode 100644
index 0d50164557..0000000000
--- a/contrib/go/_std_1.18/src/math/big/sqrt.go
+++ /dev/null
@@ -1,128 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package big
-
-import (
-	"math"
-	"sync"
-)
-
-var threeOnce struct {
-	sync.Once
-	v *Float
-}
-
-func three() *Float {
-	threeOnce.Do(func() {
-		threeOnce.v = NewFloat(3.0)
-	})
-	return threeOnce.v
-}
-
-// Sqrt sets z to the rounded square root of x, and returns it.
-//
-// If z's precision is 0, it is changed to x's precision before the
-// operation. Rounding is performed according to z's precision and
-// rounding mode, but z's accuracy is not computed. Specifically, the
-// result of z.Acc() is undefined.
-//
-// The function panics if z < 0. The value of z is undefined in that
-// case.
-func (z *Float) Sqrt(x *Float) *Float {
-	if debugFloat {
-		x.validate()
-	}
-
-	if z.prec == 0 {
-		z.prec = x.prec
-	}
-
-	if x.Sign() == -1 {
-		// following IEEE754-2008 (section 7.2)
-		panic(ErrNaN{"square root of negative operand"})
-	}
-
-	// handle ±0 and +∞
-	if x.form != finite {
-		z.acc = Exact
-		z.form = x.form
-		z.neg = x.neg // IEEE754-2008 requires √±0 = ±0
-		return z
-	}
-
-	// MantExp sets the argument's precision to the receiver's, and
-	// when z.prec > x.prec this will lower z.prec. Restore it after
-	// the MantExp call.
-	prec := z.prec
-	b := x.MantExp(z)
-	z.prec = prec
-
-	// Compute √(z·2**b) as
-	//   √( z)·2**(½b)     if b is even
-	//   √(2z)·2**(⌊½b⌋)   if b > 0 is odd
-	//   √(½z)·2**(⌈½b⌉)   if b < 0 is odd
-	switch b % 2 {
-	case 0:
-		// nothing to do
-	case 1:
-		z.exp++
-	case -1:
-		z.exp--
-	}
-	// 0.25 <= z < 2.0
-
-	// Solving 1/x² - z = 0 avoids Quo calls and is faster, especially
-	// for high precisions.
-	z.sqrtInverse(z)
-
-	// re-attach halved exponent
-	return z.SetMantExp(z, b/2)
-}
-
-// Compute √x (to z.prec precision) by solving
-//   1/t² - x = 0
-// for t (using Newton's method), and then inverting.
-func (z *Float) sqrtInverse(x *Float) {
-	// let
-	//   f(t) = 1/t² - x
-	// then
-	//   g(t) = f(t)/f'(t) = -½t(1 - xt²)
-	// and the next guess is given by
-	//   t2 = t - g(t) = ½t(3 - xt²)
-	u := newFloat(z.prec)
-	v := newFloat(z.prec)
-	three := three()
-	ng := func(t *Float) *Float {
-		u.prec = t.prec
-		v.prec = t.prec
-		u.Mul(t, t)     // u = t²
-		u.Mul(x, u)     //   = xt²
-		v.Sub(three, u) // v = 3 - xt²
-		u.Mul(t, v)     // u = t(3 - xt²)
-		u.exp--         //   = ½t(3 - xt²)
-		return t.Set(u)
-	}
-
-	xf, _ := x.Float64()
-	sqi := newFloat(z.prec)
-	sqi.SetFloat64(1 / math.Sqrt(xf))
-	for prec := z.prec + 32; sqi.prec < prec; {
-		sqi.prec *= 2
-		sqi = ng(sqi)
-	}
-	// sqi = 1/√x
-
-	// x/√x = √x
-	z.Mul(x, sqi)
-}
-
-// newFloat returns a new *Float with space for twice the given
-// precision.
-func newFloat(prec2 uint32) *Float {
-	z := new(Float)
-	// nat.make ensures the slice length is > 0
-	z.mant = z.mant.make(int(prec2/_W) * 2)
-	return z
-}
diff --git a/contrib/go/_std_1.18/src/math/bits.go b/contrib/go/_std_1.18/src/math/bits.go
deleted file mode 100644
index 77bcdbe1ce..0000000000
--- a/contrib/go/_std_1.18/src/math/bits.go
+++ /dev/null
@@ -1,62 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-const (
-	uvnan    = 0x7FF8000000000001
-	uvinf    = 0x7FF0000000000000
-	uvneginf = 0xFFF0000000000000
-	uvone    = 0x3FF0000000000000
-	mask     = 0x7FF
-	shift    = 64 - 11 - 1
-	bias     = 1023
-	signMask = 1 << 63
-	fracMask = 1<<shift - 1
-)
-
-// Inf returns positive infinity if sign >= 0, negative infinity if sign < 0.
-func Inf(sign int) float64 {
-	var v uint64
-	if sign >= 0 {
-		v = uvinf
-	} else {
-		v = uvneginf
-	}
-	return Float64frombits(v)
-}
-
-// NaN returns an IEEE 754 ``not-a-number'' value.
-func NaN() float64 { return Float64frombits(uvnan) }
-
-// IsNaN reports whether f is an IEEE 754 ``not-a-number'' value.
-func IsNaN(f float64) (is bool) {
-	// IEEE 754 says that only NaNs satisfy f != f.
-	// To avoid the floating-point hardware, could use:
-	//	x := Float64bits(f);
-	//	return uint32(x>>shift)&mask == mask && x != uvinf && x != uvneginf
-	return f != f
-}
-
-// IsInf reports whether f is an infinity, according to sign.
-// If sign > 0, IsInf reports whether f is positive infinity.
-// If sign < 0, IsInf reports whether f is negative infinity.
-// If sign == 0, IsInf reports whether f is either infinity.
-func IsInf(f float64, sign int) bool {
-	// Test for infinity by comparing against maximum float.
-	// To avoid the floating-point hardware, could use:
-	//	x := Float64bits(f);
-	//	return sign >= 0 && x == uvinf || sign <= 0 && x == uvneginf;
-	return sign >= 0 && f > MaxFloat64 || sign <= 0 && f < -MaxFloat64
-}
-
-// normalize returns a normal number y and exponent exp
-// satisfying x == y × 2**exp. It assumes x is finite and non-zero.
-func normalize(x float64) (y float64, exp int) {
-	const SmallestNormal = 2.2250738585072014e-308 // 2**-1022
-	if Abs(x) < SmallestNormal {
-		return x * (1 << 52), -52
-	}
-	return x, 0
-}
diff --git a/contrib/go/_std_1.18/src/math/cbrt.go b/contrib/go/_std_1.18/src/math/cbrt.go
deleted file mode 100644
index 45c8ecb3a8..0000000000
--- a/contrib/go/_std_1.18/src/math/cbrt.go
+++ /dev/null
@@ -1,84 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-// The go code is a modified version of the original C code from
-// http://www.netlib.org/fdlibm/s_cbrt.c and came with this notice.
-//
-// ====================================================
-// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
-//
-// Developed at SunSoft, a Sun Microsystems, Inc. business.
-// Permission to use, copy, modify, and distribute this
-// software is freely granted, provided that this notice
-// is preserved.
-// ====================================================
-
-// Cbrt returns the cube root of x.
-//
-// Special cases are:
-//	Cbrt(±0) = ±0
-//	Cbrt(±Inf) = ±Inf
-//	Cbrt(NaN) = NaN
-func Cbrt(x float64) float64 {
-	if haveArchCbrt {
-		return archCbrt(x)
-	}
-	return cbrt(x)
-}
-
-func cbrt(x float64) float64 {
-	const (
-		B1             = 715094163                   // (682-0.03306235651)*2**20
-		B2             = 696219795                   // (664-0.03306235651)*2**20
-		C              = 5.42857142857142815906e-01  // 19/35     = 0x3FE15F15F15F15F1
-		D              = -7.05306122448979611050e-01 // -864/1225 = 0xBFE691DE2532C834
-		E              = 1.41428571428571436819e+00  // 99/70     = 0x3FF6A0EA0EA0EA0F
-		F              = 1.60714285714285720630e+00  // 45/28     = 0x3FF9B6DB6DB6DB6E
-		G              = 3.57142857142857150787e-01  // 5/14      = 0x3FD6DB6DB6DB6DB7
-		SmallestNormal = 2.22507385850720138309e-308 // 2**-1022  = 0x0010000000000000
-	)
-	// special cases
-	switch {
-	case x == 0 || IsNaN(x) || IsInf(x, 0):
-		return x
-	}
-
-	sign := false
-	if x < 0 {
-		x = -x
-		sign = true
-	}
-
-	// rough cbrt to 5 bits
-	t := Float64frombits(Float64bits(x)/3 + B1<<32)
-	if x < SmallestNormal {
-		// subnormal number
-		t = float64(1 << 54) // set t= 2**54
-		t *= x
-		t = Float64frombits(Float64bits(t)/3 + B2<<32)
-	}
-
-	// new cbrt to 23 bits
-	r := t * t / x
-	s := C + r*t
-	t *= G + F/(s+E+D/s)
-
-	// chop to 22 bits, make larger than cbrt(x)
-	t = Float64frombits(Float64bits(t)&(0xFFFFFFFFC<<28) + 1<<30)
-
-	// one step newton iteration to 53 bits with error less than 0.667ulps
-	s = t * t // t*t is exact
-	r = x / s
-	w := t + t
-	r = (r - t) / (w + r) // r-s is exact
-	t = t + t*r
-
-	// restore the sign bit
-	if sign {
-		t = -t
-	}
-	return t
-}
diff --git a/contrib/go/_std_1.18/src/math/copysign.go b/contrib/go/_std_1.18/src/math/copysign.go
deleted file mode 100644
index 719c64b9eb..0000000000
--- a/contrib/go/_std_1.18/src/math/copysign.go
+++ /dev/null
@@ -1,12 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-// Copysign returns a value with the magnitude
-// of x and the sign of y.
-func Copysign(x, y float64) float64 {
-	const sign = 1 << 63
-	return Float64frombits(Float64bits(x)&^sign | Float64bits(y)&sign)
-}
diff --git a/contrib/go/_std_1.18/src/math/dim.go b/contrib/go/_std_1.18/src/math/dim.go
deleted file mode 100644
index 6a857bbe41..0000000000
--- a/contrib/go/_std_1.18/src/math/dim.go
+++ /dev/null
@@ -1,91 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-// Dim returns the maximum of x-y or 0.
-//
-// Special cases are:
-//	Dim(+Inf, +Inf) = NaN
-//	Dim(-Inf, -Inf) = NaN
-//	Dim(x, NaN) = Dim(NaN, x) = NaN
-func Dim(x, y float64) float64 {
-	// The special cases result in NaN after the subtraction:
-	//      +Inf - +Inf = NaN
-	//      -Inf - -Inf = NaN
-	//       NaN - y    = NaN
-	//         x - NaN  = NaN
-	v := x - y
-	if v <= 0 {
-		// v is negative or 0
-		return 0
-	}
-	// v is positive or NaN
-	return v
-}
-
-// Max returns the larger of x or y.
-//
-// Special cases are:
-//	Max(x, +Inf) = Max(+Inf, x) = +Inf
-//	Max(x, NaN) = Max(NaN, x) = NaN
-//	Max(+0, ±0) = Max(±0, +0) = +0
-//	Max(-0, -0) = -0
-func Max(x, y float64) float64 {
-	if haveArchMax {
-		return archMax(x, y)
-	}
-	return max(x, y)
-}
-
-func max(x, y float64) float64 {
-	// special cases
-	switch {
-	case IsInf(x, 1) || IsInf(y, 1):
-		return Inf(1)
-	case IsNaN(x) || IsNaN(y):
-		return NaN()
-	case x == 0 && x == y:
-		if Signbit(x) {
-			return y
-		}
-		return x
-	}
-	if x > y {
-		return x
-	}
-	return y
-}
-
-// Min returns the smaller of x or y.
-//
-// Special cases are:
-//	Min(x, -Inf) = Min(-Inf, x) = -Inf
-//	Min(x, NaN) = Min(NaN, x) = NaN
-//	Min(-0, ±0) = Min(±0, -0) = -0
-func Min(x, y float64) float64 {
-	if haveArchMin {
-		return archMin(x, y)
-	}
-	return min(x, y)
-}
-
-func min(x, y float64) float64 {
-	// special cases
-	switch {
-	case IsInf(x, -1) || IsInf(y, -1):
-		return Inf(-1)
-	case IsNaN(x) || IsNaN(y):
-		return NaN()
-	case x == 0 && x == y:
-		if Signbit(x) {
-			return x
-		}
-		return y
-	}
-	if x < y {
-		return x
-	}
-	return y
-}
diff --git a/contrib/go/_std_1.18/src/math/erf.go b/contrib/go/_std_1.18/src/math/erf.go
deleted file mode 100644
index 4d6fe472f1..0000000000
--- a/contrib/go/_std_1.18/src/math/erf.go
+++ /dev/null
@@ -1,349 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-/*
-	Floating-point error function and complementary error function.
-*/
-
-// The original C code and the long comment below are
-// from FreeBSD's /usr/src/lib/msun/src/s_erf.c and
-// came with this notice. The go code is a simplified
-// version of the original C.
-//
-// ====================================================
-// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
-//
-// Developed at SunPro, a Sun Microsystems, Inc. business.
-// Permission to use, copy, modify, and distribute this
-// software is freely granted, provided that this notice
-// is preserved.
-// ====================================================
-//
-//
-// double erf(double x)
-// double erfc(double x)
-//                           x
-//                    2      |\
-//     erf(x)  =  ---------  | exp(-t*t)dt
-//                 sqrt(pi) \|
-//                           0
-//
-//     erfc(x) =  1-erf(x)
-//  Note that
-//              erf(-x) = -erf(x)
-//              erfc(-x) = 2 - erfc(x)
-//
-// Method:
-//      1. For |x| in [0, 0.84375]
-//          erf(x)  = x + x*R(x**2)
-//          erfc(x) = 1 - erf(x)           if x in [-.84375,0.25]
-//                  = 0.5 + ((0.5-x)-x*R)  if x in [0.25,0.84375]
-//         where R = P/Q where P is an odd poly of degree 8 and
-//         Q is an odd poly of degree 10.
-//                                               -57.90
-//                      | R - (erf(x)-x)/x | <= 2
-//
-//
-//         Remark. The formula is derived by noting
-//          erf(x) = (2/sqrt(pi))*(x - x**3/3 + x**5/10 - x**7/42 + ....)
-//         and that
-//          2/sqrt(pi) = 1.128379167095512573896158903121545171688
-//         is close to one. The interval is chosen because the fix
-//         point of erf(x) is near 0.6174 (i.e., erf(x)=x when x is
-//         near 0.6174), and by some experiment, 0.84375 is chosen to
-//         guarantee the error is less than one ulp for erf.
-//
-//      2. For |x| in [0.84375,1.25], let s = |x| - 1, and
-//         c = 0.84506291151 rounded to single (24 bits)
-//              erf(x)  = sign(x) * (c  + P1(s)/Q1(s))
-//              erfc(x) = (1-c)  - P1(s)/Q1(s) if x > 0
-//                        1+(c+P1(s)/Q1(s))    if x < 0
-//              |P1/Q1 - (erf(|x|)-c)| <= 2**-59.06
-//         Remark: here we use the taylor series expansion at x=1.
-//              erf(1+s) = erf(1) + s*Poly(s)
-//                       = 0.845.. + P1(s)/Q1(s)
-//         That is, we use rational approximation to approximate
-//                      erf(1+s) - (c = (single)0.84506291151)
-//         Note that |P1/Q1|< 0.078 for x in [0.84375,1.25]
-//         where
-//              P1(s) = degree 6 poly in s
-//              Q1(s) = degree 6 poly in s
-//
-//      3. For x in [1.25,1/0.35(~2.857143)],
-//              erfc(x) = (1/x)*exp(-x*x-0.5625+R1/S1)
-//              erf(x)  = 1 - erfc(x)
-//         where
-//              R1(z) = degree 7 poly in z, (z=1/x**2)
-//              S1(z) = degree 8 poly in z
-//
-//      4. For x in [1/0.35,28]
-//              erfc(x) = (1/x)*exp(-x*x-0.5625+R2/S2) if x > 0
-//                      = 2.0 - (1/x)*exp(-x*x-0.5625+R2/S2) if -6<x<0
-//                      = 2.0 - tiny            (if x <= -6)
-//              erf(x)  = sign(x)*(1.0 - erfc(x)) if x < 6, else
-//              erf(x)  = sign(x)*(1.0 - tiny)
-//         where
-//              R2(z) = degree 6 poly in z, (z=1/x**2)
-//              S2(z) = degree 7 poly in z
-//
-//      Note1:
-//         To compute exp(-x*x-0.5625+R/S), let s be a single
-//         precision number and s := x; then
-//              -x*x = -s*s + (s-x)*(s+x)
-//              exp(-x*x-0.5626+R/S) =
-//                      exp(-s*s-0.5625)*exp((s-x)*(s+x)+R/S);
-//      Note2:
-//         Here 4 and 5 make use of the asymptotic series
-//                        exp(-x*x)
-//              erfc(x) ~ ---------- * ( 1 + Poly(1/x**2) )
-//                        x*sqrt(pi)
-//         We use rational approximation to approximate
-//              g(s)=f(1/x**2) = log(erfc(x)*x) - x*x + 0.5625
-//         Here is the error bound for R1/S1 and R2/S2
-//              |R1/S1 - f(x)|  < 2**(-62.57)
-//              |R2/S2 - f(x)|  < 2**(-61.52)
-//
-//      5. For inf > x >= 28
-//              erf(x)  = sign(x) *(1 - tiny)  (raise inexact)
-//              erfc(x) = tiny*tiny (raise underflow) if x > 0
-//                      = 2 - tiny if x<0
-//
-//      7. Special case:
-//              erf(0)  = 0, erf(inf)  = 1, erf(-inf) = -1,
-//              erfc(0) = 1, erfc(inf) = 0, erfc(-inf) = 2,
-//              erfc/erf(NaN) is NaN
-
-const (
-	erx = 8.45062911510467529297e-01 // 0x3FEB0AC160000000
-	// Coefficients for approximation to  erf in [0, 0.84375]
-	efx  = 1.28379167095512586316e-01  // 0x3FC06EBA8214DB69
-	efx8 = 1.02703333676410069053e+00  // 0x3FF06EBA8214DB69
-	pp0  = 1.28379167095512558561e-01  // 0x3FC06EBA8214DB68
-	pp1  = -3.25042107247001499370e-01 // 0xBFD4CD7D691CB913
-	pp2  = -2.84817495755985104766e-02 // 0xBF9D2A51DBD7194F
-	pp3  = -5.77027029648944159157e-03 // 0xBF77A291236668E4
-	pp4  = -2.37630166566501626084e-05 // 0xBEF8EAD6120016AC
-	qq1  = 3.97917223959155352819e-01  // 0x3FD97779CDDADC09
-	qq2  = 6.50222499887672944485e-02  // 0x3FB0A54C5536CEBA
-	qq3  = 5.08130628187576562776e-03  // 0x3F74D022C4D36B0F
-	qq4  = 1.32494738004321644526e-04  // 0x3F215DC9221C1A10
-	qq5  = -3.96022827877536812320e-06 // 0xBED09C4342A26120
-	// Coefficients for approximation to  erf  in [0.84375, 1.25]
-	pa0 = -2.36211856075265944077e-03 // 0xBF6359B8BEF77538
-	pa1 = 4.14856118683748331666e-01  // 0x3FDA8D00AD92B34D
-	pa2 = -3.72207876035701323847e-01 // 0xBFD7D240FBB8C3F1
-	pa3 = 3.18346619901161753674e-01  // 0x3FD45FCA805120E4
-	pa4 = -1.10894694282396677476e-01 // 0xBFBC63983D3E28EC
-	pa5 = 3.54783043256182359371e-02  // 0x3FA22A36599795EB
-	pa6 = -2.16637559486879084300e-03 // 0xBF61BF380A96073F
-	qa1 = 1.06420880400844228286e-01  // 0x3FBB3E6618EEE323
-	qa2 = 5.40397917702171048937e-01  // 0x3FE14AF092EB6F33
-	qa3 = 7.18286544141962662868e-02  // 0x3FB2635CD99FE9A7
-	qa4 = 1.26171219808761642112e-01  // 0x3FC02660E763351F
-	qa5 = 1.36370839120290507362e-02  // 0x3F8BEDC26B51DD1C
-	qa6 = 1.19844998467991074170e-02  // 0x3F888B545735151D
-	// Coefficients for approximation to  erfc in [1.25, 1/0.35]
-	ra0 = -9.86494403484714822705e-03 // 0xBF843412600D6435
-	ra1 = -6.93858572707181764372e-01 // 0xBFE63416E4BA7360
-	ra2 = -1.05586262253232909814e+01 // 0xC0251E0441B0E726
-	ra3 = -6.23753324503260060396e+01 // 0xC04F300AE4CBA38D
-	ra4 = -1.62396669462573470355e+02 // 0xC0644CB184282266
-	ra5 = -1.84605092906711035994e+02 // 0xC067135CEBCCABB2
-	ra6 = -8.12874355063065934246e+01 // 0xC054526557E4D2F2
-	ra7 = -9.81432934416914548592e+00 // 0xC023A0EFC69AC25C
-	sa1 = 1.96512716674392571292e+01  // 0x4033A6B9BD707687
-	sa2 = 1.37657754143519042600e+02  // 0x4061350C526AE721
-	sa3 = 4.34565877475229228821e+02  // 0x407B290DD58A1A71
-	sa4 = 6.45387271733267880336e+02  // 0x40842B1921EC2868
-	sa5 = 4.29008140027567833386e+02  // 0x407AD02157700314
-	sa6 = 1.08635005541779435134e+02  // 0x405B28A3EE48AE2C
-	sa7 = 6.57024977031928170135e+00  // 0x401A47EF8E484A93
-	sa8 = -6.04244152148580987438e-02 // 0xBFAEEFF2EE749A62
-	// Coefficients for approximation to  erfc in [1/.35, 28]
-	rb0 = -9.86494292470009928597e-03 // 0xBF84341239E86F4A
-	rb1 = -7.99283237680523006574e-01 // 0xBFE993BA70C285DE
-	rb2 = -1.77579549177547519889e+01 // 0xC031C209555F995A
-	rb3 = -1.60636384855821916062e+02 // 0xC064145D43C5ED98
-	rb4 = -6.37566443368389627722e+02 // 0xC083EC881375F228
-	rb5 = -1.02509513161107724954e+03 // 0xC09004616A2E5992
-	rb6 = -4.83519191608651397019e+02 // 0xC07E384E9BDC383F
-	sb1 = 3.03380607434824582924e+01  // 0x403E568B261D5190
-	sb2 = 3.25792512996573918826e+02  // 0x40745CAE221B9F0A
-	sb3 = 1.53672958608443695994e+03  // 0x409802EB189D5118
-	sb4 = 3.19985821950859553908e+03  // 0x40A8FFB7688C246A
-	sb5 = 2.55305040643316442583e+03  // 0x40A3F219CEDF3BE6
-	sb6 = 4.74528541206955367215e+02  // 0x407DA874E79FE763
-	sb7 = -2.24409524465858183362e+01 // 0xC03670E242712D62
-)
-
-// Erf returns the error function of x.
-//
-// Special cases are:
-//	Erf(+Inf) = 1
-//	Erf(-Inf) = -1
-//	Erf(NaN) = NaN
-func Erf(x float64) float64 {
-	if haveArchErf {
-		return archErf(x)
-	}
-	return erf(x)
-}
-
-func erf(x float64) float64 {
-	const (
-		VeryTiny = 2.848094538889218e-306 // 0x0080000000000000
-		Small    = 1.0 / (1 << 28)        // 2**-28
-	)
-	// special cases
-	switch {
-	case IsNaN(x):
-		return NaN()
-	case IsInf(x, 1):
-		return 1
-	case IsInf(x, -1):
-		return -1
-	}
-	sign := false
-	if x < 0 {
-		x = -x
-		sign = true
-	}
-	if x < 0.84375 { // |x| < 0.84375
-		var temp float64
-		if x < Small { // |x| < 2**-28
-			if x < VeryTiny {
-				temp = 0.125 * (8.0*x + efx8*x) // avoid underflow
-			} else {
-				temp = x + efx*x
-			}
-		} else {
-			z := x * x
-			r := pp0 + z*(pp1+z*(pp2+z*(pp3+z*pp4)))
-			s := 1 + z*(qq1+z*(qq2+z*(qq3+z*(qq4+z*qq5))))
-			y := r / s
-			temp = x + x*y
-		}
-		if sign {
-			return -temp
-		}
-		return temp
-	}
-	if x < 1.25 { // 0.84375 <= |x| < 1.25
-		s := x - 1
-		P := pa0 + s*(pa1+s*(pa2+s*(pa3+s*(pa4+s*(pa5+s*pa6)))))
-		Q := 1 + s*(qa1+s*(qa2+s*(qa3+s*(qa4+s*(qa5+s*qa6)))))
-		if sign {
-			return -erx - P/Q
-		}
-		return erx + P/Q
-	}
-	if x >= 6 { // inf > |x| >= 6
-		if sign {
-			return -1
-		}
-		return 1
-	}
-	s := 1 / (x * x)
-	var R, S float64
-	if x < 1/0.35 { // |x| < 1 / 0.35  ~ 2.857143
-		R = ra0 + s*(ra1+s*(ra2+s*(ra3+s*(ra4+s*(ra5+s*(ra6+s*ra7))))))
-		S = 1 + s*(sa1+s*(sa2+s*(sa3+s*(sa4+s*(sa5+s*(sa6+s*(sa7+s*sa8)))))))
-	} else { // |x| >= 1 / 0.35  ~ 2.857143
-		R = rb0 + s*(rb1+s*(rb2+s*(rb3+s*(rb4+s*(rb5+s*rb6)))))
-		S = 1 + s*(sb1+s*(sb2+s*(sb3+s*(sb4+s*(sb5+s*(sb6+s*sb7))))))
-	}
-	z := Float64frombits(Float64bits(x) & 0xffffffff00000000) // pseudo-single (20-bit) precision x
-	r := Exp(-z*z-0.5625) * Exp((z-x)*(z+x)+R/S)
-	if sign {
-		return r/x - 1
-	}
-	return 1 - r/x
-}
-
-// Erfc returns the complementary error function of x.
-//
-// Special cases are:
-//	Erfc(+Inf) = 0
-//	Erfc(-Inf) = 2
-//	Erfc(NaN) = NaN
-func Erfc(x float64) float64 {
-	if haveArchErfc {
-		return archErfc(x)
-	}
-	return erfc(x)
-}
-
-func erfc(x float64) float64 {
-	const Tiny = 1.0 / (1 << 56) // 2**-56
-	// special cases
-	switch {
-	case IsNaN(x):
-		return NaN()
-	case IsInf(x, 1):
-		return 0
-	case IsInf(x, -1):
-		return 2
-	}
-	sign := false
-	if x < 0 {
-		x = -x
-		sign = true
-	}
-	if x < 0.84375 { // |x| < 0.84375
-		var temp float64
-		if x < Tiny { // |x| < 2**-56
-			temp = x
-		} else {
-			z := x * x
-			r := pp0 + z*(pp1+z*(pp2+z*(pp3+z*pp4)))
-			s := 1 + z*(qq1+z*(qq2+z*(qq3+z*(qq4+z*qq5))))
-			y := r / s
-			if x < 0.25 { // |x| < 1/4
-				temp = x + x*y
-			} else {
-				temp = 0.5 + (x*y + (x - 0.5))
-			}
-		}
-		if sign {
-			return 1 + temp
-		}
-		return 1 - temp
-	}
-	if x < 1.25 { // 0.84375 <= |x| < 1.25
-		s := x - 1
-		P := pa0 + s*(pa1+s*(pa2+s*(pa3+s*(pa4+s*(pa5+s*pa6)))))
-		Q := 1 + s*(qa1+s*(qa2+s*(qa3+s*(qa4+s*(qa5+s*qa6)))))
-		if sign {
-			return 1 + erx + P/Q
-		}
-		return 1 - erx - P/Q
-
-	}
-	if x < 28 { // |x| < 28
-		s := 1 / (x * x)
-		var R, S float64
-		if x < 1/0.35 { // |x| < 1 / 0.35 ~ 2.857143
-			R = ra0 + s*(ra1+s*(ra2+s*(ra3+s*(ra4+s*(ra5+s*(ra6+s*ra7))))))
-			S = 1 + s*(sa1+s*(sa2+s*(sa3+s*(sa4+s*(sa5+s*(sa6+s*(sa7+s*sa8)))))))
-		} else { // |x| >= 1 / 0.35 ~ 2.857143
-			if sign && x > 6 {
-				return 2 // x < -6
-			}
-			R = rb0 + s*(rb1+s*(rb2+s*(rb3+s*(rb4+s*(rb5+s*rb6)))))
-			S = 1 + s*(sb1+s*(sb2+s*(sb3+s*(sb4+s*(sb5+s*(sb6+s*sb7))))))
-		}
-		z := Float64frombits(Float64bits(x) & 0xffffffff00000000) // pseudo-single (20-bit) precision x
-		r := Exp(-z*z-0.5625) * Exp((z-x)*(z+x)+R/S)
-		if sign {
-			return 2 - r/x
-		}
-		return r / x
-	}
-	if sign {
-		return 2
-	}
-	return 0
-}
diff --git a/contrib/go/_std_1.18/src/math/erfinv.go b/contrib/go/_std_1.18/src/math/erfinv.go
deleted file mode 100644
index ee423d33e4..0000000000
--- a/contrib/go/_std_1.18/src/math/erfinv.go
+++ /dev/null
@@ -1,127 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-/*
-	Inverse of the floating-point error function.
-*/
-
-// This implementation is based on the rational approximation
-// of percentage points of normal distribution available from
-// https://www.jstor.org/stable/2347330.
-
-const (
-	// Coefficients for approximation to erf in |x| <= 0.85
-	a0 = 1.1975323115670912564578e0
-	a1 = 4.7072688112383978012285e1
-	a2 = 6.9706266534389598238465e2
-	a3 = 4.8548868893843886794648e3
-	a4 = 1.6235862515167575384252e4
-	a5 = 2.3782041382114385731252e4
-	a6 = 1.1819493347062294404278e4
-	a7 = 8.8709406962545514830200e2
-	b0 = 1.0000000000000000000e0
-	b1 = 4.2313330701600911252e1
-	b2 = 6.8718700749205790830e2
-	b3 = 5.3941960214247511077e3
-	b4 = 2.1213794301586595867e4
-	b5 = 3.9307895800092710610e4
-	b6 = 2.8729085735721942674e4
-	b7 = 5.2264952788528545610e3
-	// Coefficients for approximation to erf in 0.85 < |x| <= 1-2*exp(-25)
-	c0 = 1.42343711074968357734e0
-	c1 = 4.63033784615654529590e0
-	c2 = 5.76949722146069140550e0
-	c3 = 3.64784832476320460504e0
-	c4 = 1.27045825245236838258e0
-	c5 = 2.41780725177450611770e-1
-	c6 = 2.27238449892691845833e-2
-	c7 = 7.74545014278341407640e-4
-	d0 = 1.4142135623730950488016887e0
-	d1 = 2.9036514445419946173133295e0
-	d2 = 2.3707661626024532365971225e0
-	d3 = 9.7547832001787427186894837e-1
-	d4 = 2.0945065210512749128288442e-1
-	d5 = 2.1494160384252876777097297e-2
-	d6 = 7.7441459065157709165577218e-4
-	d7 = 1.4859850019840355905497876e-9
-	// Coefficients for approximation to erf in 1-2*exp(-25) < |x| < 1
-	e0 = 6.65790464350110377720e0
-	e1 = 5.46378491116411436990e0
-	e2 = 1.78482653991729133580e0
-	e3 = 2.96560571828504891230e-1
-	e4 = 2.65321895265761230930e-2
-	e5 = 1.24266094738807843860e-3
-	e6 = 2.71155556874348757815e-5
-	e7 = 2.01033439929228813265e-7
-	f0 = 1.414213562373095048801689e0
-	f1 = 8.482908416595164588112026e-1
-	f2 = 1.936480946950659106176712e-1
-	f3 = 2.103693768272068968719679e-2
-	f4 = 1.112800997078859844711555e-3
-	f5 = 2.611088405080593625138020e-5
-	f6 = 2.010321207683943062279931e-7
-	f7 = 2.891024605872965461538222e-15
-)
-
-// Erfinv returns the inverse error function of x.
-//
-// Special cases are:
-//	Erfinv(1) = +Inf
-//	Erfinv(-1) = -Inf
-//	Erfinv(x) = NaN if x < -1 or x > 1
-//	Erfinv(NaN) = NaN
-func Erfinv(x float64) float64 {
-	// special cases
-	if IsNaN(x) || x <= -1 || x >= 1 {
-		if x == -1 || x == 1 {
-			return Inf(int(x))
-		}
-		return NaN()
-	}
-
-	sign := false
-	if x < 0 {
-		x = -x
-		sign = true
-	}
-
-	var ans float64
-	if x <= 0.85 { // |x| <= 0.85
-		r := 0.180625 - 0.25*x*x
-		z1 := ((((((a7*r+a6)*r+a5)*r+a4)*r+a3)*r+a2)*r+a1)*r + a0
-		z2 := ((((((b7*r+b6)*r+b5)*r+b4)*r+b3)*r+b2)*r+b1)*r + b0
-		ans = (x * z1) / z2
-	} else {
-		var z1, z2 float64
-		r := Sqrt(Ln2 - Log(1.0-x))
-		if r <= 5.0 {
-			r -= 1.6
-			z1 = ((((((c7*r+c6)*r+c5)*r+c4)*r+c3)*r+c2)*r+c1)*r + c0
-			z2 = ((((((d7*r+d6)*r+d5)*r+d4)*r+d3)*r+d2)*r+d1)*r + d0
-		} else {
-			r -= 5.0
-			z1 = ((((((e7*r+e6)*r+e5)*r+e4)*r+e3)*r+e2)*r+e1)*r + e0
-			z2 = ((((((f7*r+f6)*r+f5)*r+f4)*r+f3)*r+f2)*r+f1)*r + f0
-		}
-		ans = z1 / z2
-	}
-
-	if sign {
-		return -ans
-	}
-	return ans
-}
-
-// Erfcinv returns the inverse of Erfc(x).
-//
-// Special cases are:
-//	Erfcinv(0) = +Inf
-//	Erfcinv(2) = -Inf
-//	Erfcinv(x) = NaN if x < 0 or x > 2
-//	Erfcinv(NaN) = NaN
-func Erfcinv(x float64) float64 {
-	return Erfinv(1 - x)
-}
diff --git a/contrib/go/_std_1.18/src/math/exp.go b/contrib/go/_std_1.18/src/math/exp.go
deleted file mode 100644
index d05eb91fb0..0000000000
--- a/contrib/go/_std_1.18/src/math/exp.go
+++ /dev/null
@@ -1,201 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-// Exp returns e**x, the base-e exponential of x.
-//
-// Special cases are:
-//	Exp(+Inf) = +Inf
-//	Exp(NaN) = NaN
-// Very large values overflow to 0 or +Inf.
-// Very small values underflow to 1.
-func Exp(x float64) float64 {
-	if haveArchExp {
-		return archExp(x)
-	}
-	return exp(x)
-}
-
-// The original C code, the long comment, and the constants
-// below are from FreeBSD's /usr/src/lib/msun/src/e_exp.c
-// and came with this notice. The go code is a simplified
-// version of the original C.
-//
-// ====================================================
-// Copyright (C) 2004 by Sun Microsystems, Inc. All rights reserved.
-//
-// Permission to use, copy, modify, and distribute this
-// software is freely granted, provided that this notice
-// is preserved.
-// ====================================================
-//
-//
-// exp(x)
-// Returns the exponential of x.
-//
-// Method
-//   1. Argument reduction:
-//      Reduce x to an r so that |r| <= 0.5*ln2 ~ 0.34658.
-//      Given x, find r and integer k such that
-//
-//               x = k*ln2 + r,  |r| <= 0.5*ln2.
-//
-//      Here r will be represented as r = hi-lo for better
-//      accuracy.
-//
-//   2. Approximation of exp(r) by a special rational function on
-//      the interval [0,0.34658]:
-//      Write
-//          R(r**2) = r*(exp(r)+1)/(exp(r)-1) = 2 + r*r/6 - r**4/360 + ...
-//      We use a special Remez algorithm on [0,0.34658] to generate
-//      a polynomial of degree 5 to approximate R. The maximum error
-//      of this polynomial approximation is bounded by 2**-59. In
-//      other words,
-//          R(z) ~ 2.0 + P1*z + P2*z**2 + P3*z**3 + P4*z**4 + P5*z**5
-//      (where z=r*r, and the values of P1 to P5 are listed below)
-//      and
-//          |                  5          |     -59
-//          | 2.0+P1*z+...+P5*z   -  R(z) | <= 2
-//          |                             |
-//      The computation of exp(r) thus becomes
-//                             2*r
-//              exp(r) = 1 + -------
-//                            R - r
-//                                 r*R1(r)
-//                     = 1 + r + ----------- (for better accuracy)
-//                                2 - R1(r)
-//      where
-//                               2       4             10
-//              R1(r) = r - (P1*r  + P2*r  + ... + P5*r   ).
-//
-//   3. Scale back to obtain exp(x):
-//      From step 1, we have
-//         exp(x) = 2**k * exp(r)
-//
-// Special cases:
-//      exp(INF) is INF, exp(NaN) is NaN;
-//      exp(-INF) is 0, and
-//      for finite argument, only exp(0)=1 is exact.
-//
-// Accuracy:
-//      according to an error analysis, the error is always less than
-//      1 ulp (unit in the last place).
-//
-// Misc. info.
-//      For IEEE double
-//          if x >  7.09782712893383973096e+02 then exp(x) overflow
-//          if x < -7.45133219101941108420e+02 then exp(x) underflow
-//
-// Constants:
-// The hexadecimal values are the intended ones for the following
-// constants. The decimal values may be used, provided that the
-// compiler will convert from decimal to binary accurately enough
-// to produce the hexadecimal values shown.
-
-func exp(x float64) float64 {
-	const (
-		Ln2Hi = 6.93147180369123816490e-01
-		Ln2Lo = 1.90821492927058770002e-10
-		Log2e = 1.44269504088896338700e+00
-
-		Overflow  = 7.09782712893383973096e+02
-		Underflow = -7.45133219101941108420e+02
-		NearZero  = 1.0 / (1 << 28) // 2**-28
-	)
-
-	// special cases
-	switch {
-	case IsNaN(x) || IsInf(x, 1):
-		return x
-	case IsInf(x, -1):
-		return 0
-	case x > Overflow:
-		return Inf(1)
-	case x < Underflow:
-		return 0
-	case -NearZero < x && x < NearZero:
-		return 1 + x
-	}
-
-	// reduce; computed as r = hi - lo for extra precision.
-	var k int
-	switch {
-	case x < 0:
-		k = int(Log2e*x - 0.5)
-	case x > 0:
-		k = int(Log2e*x + 0.5)
-	}
-	hi := x - float64(k)*Ln2Hi
-	lo := float64(k) * Ln2Lo
-
-	// compute
-	return expmulti(hi, lo, k)
-}
-
-// Exp2 returns 2**x, the base-2 exponential of x.
-//
-// Special cases are the same as Exp.
-func Exp2(x float64) float64 {
-	if haveArchExp2 {
-		return archExp2(x)
-	}
-	return exp2(x)
-}
-
-func exp2(x float64) float64 {
-	const (
-		Ln2Hi = 6.93147180369123816490e-01
-		Ln2Lo = 1.90821492927058770002e-10
-
-		Overflow  = 1.0239999999999999e+03
-		Underflow = -1.0740e+03
-	)
-
-	// special cases
-	switch {
-	case IsNaN(x) || IsInf(x, 1):
-		return x
-	case IsInf(x, -1):
-		return 0
-	case x > Overflow:
-		return Inf(1)
-	case x < Underflow:
-		return 0
-	}
-
-	// argument reduction; x = r×lg(e) + k with |r| ≤ ln(2)/2.
-	// computed as r = hi - lo for extra precision.
-	var k int
-	switch {
-	case x > 0:
-		k = int(x + 0.5)
-	case x < 0:
-		k = int(x - 0.5)
-	}
-	t := x - float64(k)
-	hi := t * Ln2Hi
-	lo := -t * Ln2Lo
-
-	// compute
-	return expmulti(hi, lo, k)
-}
-
-// exp1 returns e**r × 2**k where r = hi - lo and |r| ≤ ln(2)/2.
-func expmulti(hi, lo float64, k int) float64 {
-	const (
-		P1 = 1.66666666666666657415e-01  /* 0x3FC55555; 0x55555555 */
-		P2 = -2.77777777770155933842e-03 /* 0xBF66C16C; 0x16BEBD93 */
-		P3 = 6.61375632143793436117e-05  /* 0x3F11566A; 0xAF25DE2C */
-		P4 = -1.65339022054652515390e-06 /* 0xBEBBBD41; 0xC5D26BF1 */
-		P5 = 4.13813679705723846039e-08  /* 0x3E663769; 0x72BEA4D0 */
-	)
-
-	r := hi - lo
-	t := r * r
-	c := r - t*(P1+t*(P2+t*(P3+t*(P4+t*P5))))
-	y := 1 - ((lo - (r*c)/(2-c)) - hi)
-	// TODO(rsc): make sure Ldexp can handle boundary k
-	return Ldexp(y, k)
-}
diff --git a/contrib/go/_std_1.18/src/math/expm1.go b/contrib/go/_std_1.18/src/math/expm1.go
deleted file mode 100644
index 66d3421661..0000000000
--- a/contrib/go/_std_1.18/src/math/expm1.go
+++ /dev/null
@@ -1,242 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-// The original C code, the long comment, and the constants
-// below are from FreeBSD's /usr/src/lib/msun/src/s_expm1.c
-// and came with this notice. The go code is a simplified
-// version of the original C.
-//
-// ====================================================
-// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
-//
-// Developed at SunPro, a Sun Microsystems, Inc. business.
-// Permission to use, copy, modify, and distribute this
-// software is freely granted, provided that this notice
-// is preserved.
-// ====================================================
-//
-// expm1(x)
-// Returns exp(x)-1, the exponential of x minus 1.
-//
-// Method
-//   1. Argument reduction:
-//      Given x, find r and integer k such that
-//
-//               x = k*ln2 + r,  |r| <= 0.5*ln2 ~ 0.34658
-//
-//      Here a correction term c will be computed to compensate
-//      the error in r when rounded to a floating-point number.
-//
-//   2. Approximating expm1(r) by a special rational function on
-//      the interval [0,0.34658]:
-//      Since
-//          r*(exp(r)+1)/(exp(r)-1) = 2+ r**2/6 - r**4/360 + ...
-//      we define R1(r*r) by
-//          r*(exp(r)+1)/(exp(r)-1) = 2+ r**2/6 * R1(r*r)
-//      That is,
-//          R1(r**2) = 6/r *((exp(r)+1)/(exp(r)-1) - 2/r)
-//                   = 6/r * ( 1 + 2.0*(1/(exp(r)-1) - 1/r))
-//                   = 1 - r**2/60 + r**4/2520 - r**6/100800 + ...
-//      We use a special Reme algorithm on [0,0.347] to generate
-//      a polynomial of degree 5 in r*r to approximate R1. The
-//      maximum error of this polynomial approximation is bounded
-//      by 2**-61. In other words,
-//          R1(z) ~ 1.0 + Q1*z + Q2*z**2 + Q3*z**3 + Q4*z**4 + Q5*z**5
-//      where   Q1  =  -1.6666666666666567384E-2,
-//              Q2  =   3.9682539681370365873E-4,
-//              Q3  =  -9.9206344733435987357E-6,
-//              Q4  =   2.5051361420808517002E-7,
-//              Q5  =  -6.2843505682382617102E-9;
-//      (where z=r*r, and the values of Q1 to Q5 are listed below)
-//      with error bounded by
-//          |                  5           |     -61
-//          | 1.0+Q1*z+...+Q5*z   -  R1(z) | <= 2
-//          |                              |
-//
-//      expm1(r) = exp(r)-1 is then computed by the following
-//      specific way which minimize the accumulation rounding error:
-//                             2     3
-//                            r     r    [ 3 - (R1 + R1*r/2)  ]
-//            expm1(r) = r + --- + --- * [--------------------]
-//                            2     2    [ 6 - r*(3 - R1*r/2) ]
-//
-//      To compensate the error in the argument reduction, we use
-//              expm1(r+c) = expm1(r) + c + expm1(r)*c
-//                         ~ expm1(r) + c + r*c
-//      Thus c+r*c will be added in as the correction terms for
-//      expm1(r+c). Now rearrange the term to avoid optimization
-//      screw up:
-//                      (      2                                    2 )
-//                      ({  ( r    [ R1 -  (3 - R1*r/2) ]  )  }    r  )
-//       expm1(r+c)~r - ({r*(--- * [--------------------]-c)-c} - --- )
-//                      ({  ( 2    [ 6 - r*(3 - R1*r/2) ]  )  }    2  )
-//                      (                                             )
-//
-//                 = r - E
-//   3. Scale back to obtain expm1(x):
-//      From step 1, we have
-//         expm1(x) = either 2**k*[expm1(r)+1] - 1
-//                  = or     2**k*[expm1(r) + (1-2**-k)]
-//   4. Implementation notes:
-//      (A). To save one multiplication, we scale the coefficient Qi
-//           to Qi*2**i, and replace z by (x**2)/2.
-//      (B). To achieve maximum accuracy, we compute expm1(x) by
-//        (i)   if x < -56*ln2, return -1.0, (raise inexact if x!=inf)
-//        (ii)  if k=0, return r-E
-//        (iii) if k=-1, return 0.5*(r-E)-0.5
-//        (iv)  if k=1 if r < -0.25, return 2*((r+0.5)- E)
-//                     else          return  1.0+2.0*(r-E);
-//        (v)   if (k<-2||k>56) return 2**k(1-(E-r)) - 1 (or exp(x)-1)
-//        (vi)  if k <= 20, return 2**k((1-2**-k)-(E-r)), else
-//        (vii) return 2**k(1-((E+2**-k)-r))
-//
-// Special cases:
-//      expm1(INF) is INF, expm1(NaN) is NaN;
-//      expm1(-INF) is -1, and
-//      for finite argument, only expm1(0)=0 is exact.
-//
-// Accuracy:
-//      according to an error analysis, the error is always less than
-//      1 ulp (unit in the last place).
-//
-// Misc. info.
-//      For IEEE double
-//          if x >  7.09782712893383973096e+02 then expm1(x) overflow
-//
-// Constants:
-// The hexadecimal values are the intended ones for the following
-// constants. The decimal values may be used, provided that the
-// compiler will convert from decimal to binary accurately enough
-// to produce the hexadecimal values shown.
-//
-
-// Expm1 returns e**x - 1, the base-e exponential of x minus 1.
-// It is more accurate than Exp(x) - 1 when x is near zero.
-//
-// Special cases are:
-//	Expm1(+Inf) = +Inf
-//	Expm1(-Inf) = -1
-//	Expm1(NaN) = NaN
-// Very large values overflow to -1 or +Inf.
-func Expm1(x float64) float64 {
-	if haveArchExpm1 {
-		return archExpm1(x)
-	}
-	return expm1(x)
-}
-
-func expm1(x float64) float64 {
-	const (
-		Othreshold = 7.09782712893383973096e+02 // 0x40862E42FEFA39EF
-		Ln2X56     = 3.88162421113569373274e+01 // 0x4043687a9f1af2b1
-		Ln2HalfX3  = 1.03972077083991796413e+00 // 0x3ff0a2b23f3bab73
-		Ln2Half    = 3.46573590279972654709e-01 // 0x3fd62e42fefa39ef
-		Ln2Hi      = 6.93147180369123816490e-01 // 0x3fe62e42fee00000
-		Ln2Lo      = 1.90821492927058770002e-10 // 0x3dea39ef35793c76
-		InvLn2     = 1.44269504088896338700e+00 // 0x3ff71547652b82fe
-		Tiny       = 1.0 / (1 << 54)            // 2**-54 = 0x3c90000000000000
-		// scaled coefficients related to expm1
-		Q1 = -3.33333333333331316428e-02 // 0xBFA11111111110F4
-		Q2 = 1.58730158725481460165e-03  // 0x3F5A01A019FE5585
-		Q3 = -7.93650757867487942473e-05 // 0xBF14CE199EAADBB7
-		Q4 = 4.00821782732936239552e-06  // 0x3ED0CFCA86E65239
-		Q5 = -2.01099218183624371326e-07 // 0xBE8AFDB76E09C32D
-	)
-
-	// special cases
-	switch {
-	case IsInf(x, 1) || IsNaN(x):
-		return x
-	case IsInf(x, -1):
-		return -1
-	}
-
-	absx := x
-	sign := false
-	if x < 0 {
-		absx = -absx
-		sign = true
-	}
-
-	// filter out huge argument
-	if absx >= Ln2X56 { // if |x| >= 56 * ln2
-		if sign {
-			return -1 // x < -56*ln2, return -1
-		}
-		if absx >= Othreshold { // if |x| >= 709.78...
-			return Inf(1)
-		}
-	}
-
-	// argument reduction
-	var c float64
-	var k int
-	if absx > Ln2Half { // if  |x| > 0.5 * ln2
-		var hi, lo float64
-		if absx < Ln2HalfX3 { // and |x| < 1.5 * ln2
-			if !sign {
-				hi = x - Ln2Hi
-				lo = Ln2Lo
-				k = 1
-			} else {
-				hi = x + Ln2Hi
-				lo = -Ln2Lo
-				k = -1
-			}
-		} else {
-			if !sign {
-				k = int(InvLn2*x + 0.5)
-			} else {
-				k = int(InvLn2*x - 0.5)
-			}
-			t := float64(k)
-			hi = x - t*Ln2Hi // t * Ln2Hi is exact here
-			lo = t * Ln2Lo
-		}
-		x = hi - lo
-		c = (hi - x) - lo
-	} else if absx < Tiny { // when |x| < 2**-54, return x
-		return x
-	} else {
-		k = 0
-	}
-
-	// x is now in primary range
-	hfx := 0.5 * x
-	hxs := x * hfx
-	r1 := 1 + hxs*(Q1+hxs*(Q2+hxs*(Q3+hxs*(Q4+hxs*Q5))))
-	t := 3 - r1*hfx
-	e := hxs * ((r1 - t) / (6.0 - x*t))
-	if k == 0 {
-		return x - (x*e - hxs) // c is 0
-	}
-	e = (x*(e-c) - c)
-	e -= hxs
-	switch {
-	case k == -1:
-		return 0.5*(x-e) - 0.5
-	case k == 1:
-		if x < -0.25 {
-			return -2 * (e - (x + 0.5))
-		}
-		return 1 + 2*(x-e)
-	case k <= -2 || k > 56: // suffice to return exp(x)-1
-		y := 1 - (e - x)
-		y = Float64frombits(Float64bits(y) + uint64(k)<<52) // add k to y's exponent
-		return y - 1
-	}
-	if k < 20 {
-		t := Float64frombits(0x3ff0000000000000 - (0x20000000000000 >> uint(k))) // t=1-2**-k
-		y := t - (e - x)
-		y = Float64frombits(Float64bits(y) + uint64(k)<<52) // add k to y's exponent
-		return y
-	}
-	t = Float64frombits(uint64(0x3ff-k) << 52) // 2**-k
-	y := x - (e + t)
-	y++
-	y = Float64frombits(Float64bits(y) + uint64(k)<<52) // add k to y's exponent
-	return y
-}
diff --git a/contrib/go/_std_1.18/src/math/floor.go b/contrib/go/_std_1.18/src/math/floor.go
deleted file mode 100644
index 7913a900e3..0000000000
--- a/contrib/go/_std_1.18/src/math/floor.go
+++ /dev/null
@@ -1,146 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-// Floor returns the greatest integer value less than or equal to x.
-//
-// Special cases are:
-//	Floor(±0) = ±0
-//	Floor(±Inf) = ±Inf
-//	Floor(NaN) = NaN
-func Floor(x float64) float64 {
-	if haveArchFloor {
-		return archFloor(x)
-	}
-	return floor(x)
-}
-
-func floor(x float64) float64 {
-	if x == 0 || IsNaN(x) || IsInf(x, 0) {
-		return x
-	}
-	if x < 0 {
-		d, fract := Modf(-x)
-		if fract != 0.0 {
-			d = d + 1
-		}
-		return -d
-	}
-	d, _ := Modf(x)
-	return d
-}
-
-// Ceil returns the least integer value greater than or equal to x.
-//
-// Special cases are:
-//	Ceil(±0) = ±0
-//	Ceil(±Inf) = ±Inf
-//	Ceil(NaN) = NaN
-func Ceil(x float64) float64 {
-	if haveArchCeil {
-		return archCeil(x)
-	}
-	return ceil(x)
-}
-
-func ceil(x float64) float64 {
-	return -Floor(-x)
-}
-
-// Trunc returns the integer value of x.
-//
-// Special cases are:
-//	Trunc(±0) = ±0
-//	Trunc(±Inf) = ±Inf
-//	Trunc(NaN) = NaN
-func Trunc(x float64) float64 {
-	if haveArchTrunc {
-		return archTrunc(x)
-	}
-	return trunc(x)
-}
-
-func trunc(x float64) float64 {
-	if x == 0 || IsNaN(x) || IsInf(x, 0) {
-		return x
-	}
-	d, _ := Modf(x)
-	return d
-}
-
-// Round returns the nearest integer, rounding half away from zero.
-//
-// Special cases are:
-//	Round(±0) = ±0
-//	Round(±Inf) = ±Inf
-//	Round(NaN) = NaN
-func Round(x float64) float64 {
-	// Round is a faster implementation of:
-	//
-	// func Round(x float64) float64 {
-	//   t := Trunc(x)
-	//   if Abs(x-t) >= 0.5 {
-	//     return t + Copysign(1, x)
-	//   }
-	//   return t
-	// }
-	bits := Float64bits(x)
-	e := uint(bits>>shift) & mask
-	if e < bias {
-		// Round abs(x) < 1 including denormals.
-		bits &= signMask // +-0
-		if e == bias-1 {
-			bits |= uvone // +-1
-		}
-	} else if e < bias+shift {
-		// Round any abs(x) >= 1 containing a fractional component [0,1).
-		//
-		// Numbers with larger exponents are returned unchanged since they
-		// must be either an integer, infinity, or NaN.
-		const half = 1 << (shift - 1)
-		e -= bias
-		bits += half >> e
-		bits &^= fracMask >> e
-	}
-	return Float64frombits(bits)
-}
-
-// RoundToEven returns the nearest integer, rounding ties to even.
-//
-// Special cases are:
-//	RoundToEven(±0) = ±0
-//	RoundToEven(±Inf) = ±Inf
-//	RoundToEven(NaN) = NaN
-func RoundToEven(x float64) float64 {
-	// RoundToEven is a faster implementation of:
-	//
-	// func RoundToEven(x float64) float64 {
-	//   t := math.Trunc(x)
-	//   odd := math.Remainder(t, 2) != 0
-	//   if d := math.Abs(x - t); d > 0.5 || (d == 0.5 && odd) {
-	//     return t + math.Copysign(1, x)
-	//   }
-	//   return t
-	// }
-	bits := Float64bits(x)
-	e := uint(bits>>shift) & mask
-	if e >= bias {
-		// Round abs(x) >= 1.
-		// - Large numbers without fractional components, infinity, and NaN are unchanged.
-		// - Add 0.499.. or 0.5 before truncating depending on whether the truncated
-		//   number is even or odd (respectively).
-		const halfMinusULP = (1 << (shift - 1)) - 1
-		e -= bias
-		bits += (halfMinusULP + (bits>>(shift-e))&1) >> e
-		bits &^= fracMask >> e
-	} else if e == bias-1 && bits&fracMask != 0 {
-		// Round 0.5 < abs(x) < 1.
-		bits = bits&signMask | uvone // +-1
-	} else {
-		// Round abs(x) <= 0.5 including denormals.
-		bits &= signMask // +-0
-	}
-	return Float64frombits(bits)
-}
diff --git a/contrib/go/_std_1.18/src/math/frexp.go b/contrib/go/_std_1.18/src/math/frexp.go
deleted file mode 100644
index 3c8a909ed0..0000000000
--- a/contrib/go/_std_1.18/src/math/frexp.go
+++ /dev/null
@@ -1,38 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-// Frexp breaks f into a normalized fraction
-// and an integral power of two.
-// It returns frac and exp satisfying f == frac × 2**exp,
-// with the absolute value of frac in the interval [½, 1).
-//
-// Special cases are:
-//	Frexp(±0) = ±0, 0
-//	Frexp(±Inf) = ±Inf, 0
-//	Frexp(NaN) = NaN, 0
-func Frexp(f float64) (frac float64, exp int) {
-	if haveArchFrexp {
-		return archFrexp(f)
-	}
-	return frexp(f)
-}
-
-func frexp(f float64) (frac float64, exp int) {
-	// special cases
-	switch {
-	case f == 0:
-		return f, 0 // correctly return -0
-	case IsInf(f, 0) || IsNaN(f):
-		return f, 0
-	}
-	f, exp = normalize(f)
-	x := Float64bits(f)
-	exp += int((x>>shift)&mask) - bias + 1
-	x &^= mask << shift
-	x |= (-1 + bias) << shift
-	frac = Float64frombits(x)
-	return
-}
diff --git a/contrib/go/_std_1.18/src/math/gamma.go b/contrib/go/_std_1.18/src/math/gamma.go
deleted file mode 100644
index cc9e869496..0000000000
--- a/contrib/go/_std_1.18/src/math/gamma.go
+++ /dev/null
@@ -1,221 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-// The original C code, the long comment, and the constants
-// below are from http://netlib.sandia.gov/cephes/cprob/gamma.c.
-// The go code is a simplified version of the original C.
-//
-//      tgamma.c
-//
-//      Gamma function
-//
-// SYNOPSIS:
-//
-// double x, y, tgamma();
-// extern int signgam;
-//
-// y = tgamma( x );
-//
-// DESCRIPTION:
-//
-// Returns gamma function of the argument. The result is
-// correctly signed, and the sign (+1 or -1) is also
-// returned in a global (extern) variable named signgam.
-// This variable is also filled in by the logarithmic gamma
-// function lgamma().
-//
-// Arguments |x| <= 34 are reduced by recurrence and the function
-// approximated by a rational function of degree 6/7 in the
-// interval (2,3).  Large arguments are handled by Stirling's
-// formula. Large negative arguments are made positive using
-// a reflection formula.
-//
-// ACCURACY:
-//
-//                      Relative error:
-// arithmetic   domain     # trials      peak         rms
-//    DEC      -34, 34      10000       1.3e-16     2.5e-17
-//    IEEE    -170,-33      20000       2.3e-15     3.3e-16
-//    IEEE     -33,  33     20000       9.4e-16     2.2e-16
-//    IEEE      33, 171.6   20000       2.3e-15     3.2e-16
-//
-// Error for arguments outside the test range will be larger
-// owing to error amplification by the exponential function.
-//
-// Cephes Math Library Release 2.8:  June, 2000
-// Copyright 1984, 1987, 1989, 1992, 2000 by Stephen L. Moshier
-//
-// The readme file at http://netlib.sandia.gov/cephes/ says:
-//    Some software in this archive may be from the book _Methods and
-// Programs for Mathematical Functions_ (Prentice-Hall or Simon & Schuster
-// International, 1989) or from the Cephes Mathematical Library, a
-// commercial product. In either event, it is copyrighted by the author.
-// What you see here may be used freely but it comes with no support or
-// guarantee.
-//
-//   The two known misprints in the book are repaired here in the
-// source listings for the gamma function and the incomplete beta
-// integral.
-//
-//   Stephen L. Moshier
-//   moshier@na-net.ornl.gov
-
-var _gamP = [...]float64{
-	1.60119522476751861407e-04,
-	1.19135147006586384913e-03,
-	1.04213797561761569935e-02,
-	4.76367800457137231464e-02,
-	2.07448227648435975150e-01,
-	4.94214826801497100753e-01,
-	9.99999999999999996796e-01,
-}
-var _gamQ = [...]float64{
-	-2.31581873324120129819e-05,
-	5.39605580493303397842e-04,
-	-4.45641913851797240494e-03,
-	1.18139785222060435552e-02,
-	3.58236398605498653373e-02,
-	-2.34591795718243348568e-01,
-	7.14304917030273074085e-02,
-	1.00000000000000000320e+00,
-}
-var _gamS = [...]float64{
-	7.87311395793093628397e-04,
-	-2.29549961613378126380e-04,
-	-2.68132617805781232825e-03,
-	3.47222221605458667310e-03,
-	8.33333333333482257126e-02,
-}
-
-// Gamma function computed by Stirling's formula.
-// The pair of results must be multiplied together to get the actual answer.
-// The multiplication is left to the caller so that, if careful, the caller can avoid
-// infinity for 172 <= x <= 180.
-// The polynomial is valid for 33 <= x <= 172; larger values are only used
-// in reciprocal and produce denormalized floats. The lower precision there
-// masks any imprecision in the polynomial.
-func stirling(x float64) (float64, float64) {
-	if x > 200 {
-		return Inf(1), 1
-	}
-	const (
-		SqrtTwoPi   = 2.506628274631000502417
-		MaxStirling = 143.01608
-	)
-	w := 1 / x
-	w = 1 + w*((((_gamS[0]*w+_gamS[1])*w+_gamS[2])*w+_gamS[3])*w+_gamS[4])
-	y1 := Exp(x)
-	y2 := 1.0
-	if x > MaxStirling { // avoid Pow() overflow
-		v := Pow(x, 0.5*x-0.25)
-		y1, y2 = v, v/y1
-	} else {
-		y1 = Pow(x, x-0.5) / y1
-	}
-	return y1, SqrtTwoPi * w * y2
-}
-
-// Gamma returns the Gamma function of x.
-//
-// Special cases are:
-//	Gamma(+Inf) = +Inf
-//	Gamma(+0) = +Inf
-//	Gamma(-0) = -Inf
-//	Gamma(x) = NaN for integer x < 0
-//	Gamma(-Inf) = NaN
-//	Gamma(NaN) = NaN
-func Gamma(x float64) float64 {
-	const Euler = 0.57721566490153286060651209008240243104215933593992 // A001620
-	// special cases
-	switch {
-	case isNegInt(x) || IsInf(x, -1) || IsNaN(x):
-		return NaN()
-	case IsInf(x, 1):
-		return Inf(1)
-	case x == 0:
-		if Signbit(x) {
-			return Inf(-1)
-		}
-		return Inf(1)
-	}
-	q := Abs(x)
-	p := Floor(q)
-	if q > 33 {
-		if x >= 0 {
-			y1, y2 := stirling(x)
-			return y1 * y2
-		}
-		// Note: x is negative but (checked above) not a negative integer,
-		// so x must be small enough to be in range for conversion to int64.
-		// If |x| were >= 2⁶³ it would have to be an integer.
-		signgam := 1
-		if ip := int64(p); ip&1 == 0 {
-			signgam = -1
-		}
-		z := q - p
-		if z > 0.5 {
-			p = p + 1
-			z = q - p
-		}
-		z = q * Sin(Pi*z)
-		if z == 0 {
-			return Inf(signgam)
-		}
-		sq1, sq2 := stirling(q)
-		absz := Abs(z)
-		d := absz * sq1 * sq2
-		if IsInf(d, 0) {
-			z = Pi / absz / sq1 / sq2
-		} else {
-			z = Pi / d
-		}
-		return float64(signgam) * z
-	}
-
-	// Reduce argument
-	z := 1.0
-	for x >= 3 {
-		x = x - 1
-		z = z * x
-	}
-	for x < 0 {
-		if x > -1e-09 {
-			goto small
-		}
-		z = z / x
-		x = x + 1
-	}
-	for x < 2 {
-		if x < 1e-09 {
-			goto small
-		}
-		z = z / x
-		x = x + 1
-	}
-
-	if x == 2 {
-		return z
-	}
-
-	x = x - 2
-	p = (((((x*_gamP[0]+_gamP[1])*x+_gamP[2])*x+_gamP[3])*x+_gamP[4])*x+_gamP[5])*x + _gamP[6]
-	q = ((((((x*_gamQ[0]+_gamQ[1])*x+_gamQ[2])*x+_gamQ[3])*x+_gamQ[4])*x+_gamQ[5])*x+_gamQ[6])*x + _gamQ[7]
-	return z * p / q
-
-small:
-	if x == 0 {
-		return Inf(1)
-	}
-	return z / ((1 + Euler*x) * x)
-}
-
-func isNegInt(x float64) bool {
-	if x < 0 {
-		_, xf := Modf(x)
-		return xf == 0
-	}
-	return false
-}
diff --git a/contrib/go/_std_1.18/src/math/hypot.go b/contrib/go/_std_1.18/src/math/hypot.go
deleted file mode 100644
index 12af17766d..0000000000
--- a/contrib/go/_std_1.18/src/math/hypot.go
+++ /dev/null
@@ -1,43 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-/*
-	Hypot -- sqrt(p*p + q*q), but overflows only if the result does.
-*/
-
-// Hypot returns Sqrt(p*p + q*q), taking care to avoid
-// unnecessary overflow and underflow.
-//
-// Special cases are:
-//	Hypot(±Inf, q) = +Inf
-//	Hypot(p, ±Inf) = +Inf
-//	Hypot(NaN, q) = NaN
-//	Hypot(p, NaN) = NaN
-func Hypot(p, q float64) float64 {
-	if haveArchHypot {
-		return archHypot(p, q)
-	}
-	return hypot(p, q)
-}
-
-func hypot(p, q float64) float64 {
-	// special cases
-	switch {
-	case IsInf(p, 0) || IsInf(q, 0):
-		return Inf(1)
-	case IsNaN(p) || IsNaN(q):
-		return NaN()
-	}
-	p, q = Abs(p), Abs(q)
-	if p < q {
-		p, q = q, p
-	}
-	if p == 0 {
-		return 0
-	}
-	q = q / p
-	return p * Sqrt(1+q*q)
-}
diff --git a/contrib/go/_std_1.18/src/math/j0.go b/contrib/go/_std_1.18/src/math/j0.go
deleted file mode 100644
index cb5f07bca6..0000000000
--- a/contrib/go/_std_1.18/src/math/j0.go
+++ /dev/null
@@ -1,427 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-/*
-	Bessel function of the first and second kinds of order zero.
-*/
-
-// The original C code and the long comment below are
-// from FreeBSD's /usr/src/lib/msun/src/e_j0.c and
-// came with this notice. The go code is a simplified
-// version of the original C.
-//
-// ====================================================
-// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
-//
-// Developed at SunPro, a Sun Microsystems, Inc. business.
-// Permission to use, copy, modify, and distribute this
-// software is freely granted, provided that this notice
-// is preserved.
-// ====================================================
-//
-// __ieee754_j0(x), __ieee754_y0(x)
-// Bessel function of the first and second kinds of order zero.
-// Method -- j0(x):
-//      1. For tiny x, we use j0(x) = 1 - x**2/4 + x**4/64 - ...
-//      2. Reduce x to |x| since j0(x)=j0(-x),  and
-//         for x in (0,2)
-//              j0(x) = 1-z/4+ z**2*R0/S0,  where z = x*x;
-//         (precision:  |j0-1+z/4-z**2R0/S0 |<2**-63.67 )
-//         for x in (2,inf)
-//              j0(x) = sqrt(2/(pi*x))*(p0(x)*cos(x0)-q0(x)*sin(x0))
-//         where x0 = x-pi/4. It is better to compute sin(x0),cos(x0)
-//         as follow:
-//              cos(x0) = cos(x)cos(pi/4)+sin(x)sin(pi/4)
-//                      = 1/sqrt(2) * (cos(x) + sin(x))
-//              sin(x0) = sin(x)cos(pi/4)-cos(x)sin(pi/4)
-//                      = 1/sqrt(2) * (sin(x) - cos(x))
-//         (To avoid cancellation, use
-//              sin(x) +- cos(x) = -cos(2x)/(sin(x) -+ cos(x))
-//         to compute the worse one.)
-//
-//      3 Special cases
-//              j0(nan)= nan
-//              j0(0) = 1
-//              j0(inf) = 0
-//
-// Method -- y0(x):
-//      1. For x<2.
-//         Since
-//              y0(x) = 2/pi*(j0(x)*(ln(x/2)+Euler) + x**2/4 - ...)
-//         therefore y0(x)-2/pi*j0(x)*ln(x) is an even function.
-//         We use the following function to approximate y0,
-//              y0(x) = U(z)/V(z) + (2/pi)*(j0(x)*ln(x)), z= x**2
-//         where
-//              U(z) = u00 + u01*z + ... + u06*z**6
-//              V(z) = 1  + v01*z + ... + v04*z**4
-//         with absolute approximation error bounded by 2**-72.
-//         Note: For tiny x, U/V = u0 and j0(x)~1, hence
-//              y0(tiny) = u0 + (2/pi)*ln(tiny), (choose tiny<2**-27)
-//      2. For x>=2.
-//              y0(x) = sqrt(2/(pi*x))*(p0(x)*cos(x0)+q0(x)*sin(x0))
-//         where x0 = x-pi/4. It is better to compute sin(x0),cos(x0)
-//         by the method mentioned above.
-//      3. Special cases: y0(0)=-inf, y0(x<0)=NaN, y0(inf)=0.
-//
-
-// J0 returns the order-zero Bessel function of the first kind.
-//
-// Special cases are:
-//	J0(±Inf) = 0
-//	J0(0) = 1
-//	J0(NaN) = NaN
-func J0(x float64) float64 {
-	const (
-		Huge   = 1e300
-		TwoM27 = 1.0 / (1 << 27) // 2**-27 0x3e40000000000000
-		TwoM13 = 1.0 / (1 << 13) // 2**-13 0x3f20000000000000
-		Two129 = 1 << 129        // 2**129 0x4800000000000000
-		// R0/S0 on [0, 2]
-		R02 = 1.56249999999999947958e-02  // 0x3F8FFFFFFFFFFFFD
-		R03 = -1.89979294238854721751e-04 // 0xBF28E6A5B61AC6E9
-		R04 = 1.82954049532700665670e-06  // 0x3EBEB1D10C503919
-		R05 = -4.61832688532103189199e-09 // 0xBE33D5E773D63FCE
-		S01 = 1.56191029464890010492e-02  // 0x3F8FFCE882C8C2A4
-		S02 = 1.16926784663337450260e-04  // 0x3F1EA6D2DD57DBF4
-		S03 = 5.13546550207318111446e-07  // 0x3EA13B54CE84D5A9
-		S04 = 1.16614003333790000205e-09  // 0x3E1408BCF4745D8F
-	)
-	// special cases
-	switch {
-	case IsNaN(x):
-		return x
-	case IsInf(x, 0):
-		return 0
-	case x == 0:
-		return 1
-	}
-
-	x = Abs(x)
-	if x >= 2 {
-		s, c := Sincos(x)
-		ss := s - c
-		cc := s + c
-
-		// make sure x+x does not overflow
-		if x < MaxFloat64/2 {
-			z := -Cos(x + x)
-			if s*c < 0 {
-				cc = z / ss
-			} else {
-				ss = z / cc
-			}
-		}
-
-		// j0(x) = 1/sqrt(pi) * (P(0,x)*cc - Q(0,x)*ss) / sqrt(x)
-		// y0(x) = 1/sqrt(pi) * (P(0,x)*ss + Q(0,x)*cc) / sqrt(x)
-
-		var z float64
-		if x > Two129 { // |x| > ~6.8056e+38
-			z = (1 / SqrtPi) * cc / Sqrt(x)
-		} else {
-			u := pzero(x)
-			v := qzero(x)
-			z = (1 / SqrtPi) * (u*cc - v*ss) / Sqrt(x)
-		}
-		return z // |x| >= 2.0
-	}
-	if x < TwoM13 { // |x| < ~1.2207e-4
-		if x < TwoM27 {
-			return 1 // |x| < ~7.4506e-9
-		}
-		return 1 - 0.25*x*x // ~7.4506e-9 < |x| < ~1.2207e-4
-	}
-	z := x * x
-	r := z * (R02 + z*(R03+z*(R04+z*R05)))
-	s := 1 + z*(S01+z*(S02+z*(S03+z*S04)))
-	if x < 1 {
-		return 1 + z*(-0.25+(r/s)) // |x| < 1.00
-	}
-	u := 0.5 * x
-	return (1+u)*(1-u) + z*(r/s) // 1.0 < |x| < 2.0
-}
-
-// Y0 returns the order-zero Bessel function of the second kind.
-//
-// Special cases are:
-//	Y0(+Inf) = 0
-//	Y0(0) = -Inf
-//	Y0(x < 0) = NaN
-//	Y0(NaN) = NaN
-func Y0(x float64) float64 {
-	const (
-		TwoM27 = 1.0 / (1 << 27)             // 2**-27 0x3e40000000000000
-		Two129 = 1 << 129                    // 2**129 0x4800000000000000
-		U00    = -7.38042951086872317523e-02 // 0xBFB2E4D699CBD01F
-		U01    = 1.76666452509181115538e-01  // 0x3FC69D019DE9E3FC
-		U02    = -1.38185671945596898896e-02 // 0xBF8C4CE8B16CFA97
-		U03    = 3.47453432093683650238e-04  // 0x3F36C54D20B29B6B
-		U04    = -3.81407053724364161125e-06 // 0xBECFFEA773D25CAD
-		U05    = 1.95590137035022920206e-08  // 0x3E5500573B4EABD4
-		U06    = -3.98205194132103398453e-11 // 0xBDC5E43D693FB3C8
-		V01    = 1.27304834834123699328e-02  // 0x3F8A127091C9C71A
-		V02    = 7.60068627350353253702e-05  // 0x3F13ECBBF578C6C1
-		V03    = 2.59150851840457805467e-07  // 0x3E91642D7FF202FD
-		V04    = 4.41110311332675467403e-10  // 0x3DFE50183BD6D9EF
-	)
-	// special cases
-	switch {
-	case x < 0 || IsNaN(x):
-		return NaN()
-	case IsInf(x, 1):
-		return 0
-	case x == 0:
-		return Inf(-1)
-	}
-
-	if x >= 2 { // |x| >= 2.0
-
-		// y0(x) = sqrt(2/(pi*x))*(p0(x)*sin(x0)+q0(x)*cos(x0))
-		//     where x0 = x-pi/4
-		// Better formula:
-		//     cos(x0) = cos(x)cos(pi/4)+sin(x)sin(pi/4)
-		//             =  1/sqrt(2) * (sin(x) + cos(x))
-		//     sin(x0) = sin(x)cos(3pi/4)-cos(x)sin(3pi/4)
-		//             =  1/sqrt(2) * (sin(x) - cos(x))
-		// To avoid cancellation, use
-		//     sin(x) +- cos(x) = -cos(2x)/(sin(x) -+ cos(x))
-		// to compute the worse one.
-
-		s, c := Sincos(x)
-		ss := s - c
-		cc := s + c
-
-		// j0(x) = 1/sqrt(pi) * (P(0,x)*cc - Q(0,x)*ss) / sqrt(x)
-		// y0(x) = 1/sqrt(pi) * (P(0,x)*ss + Q(0,x)*cc) / sqrt(x)
-
-		// make sure x+x does not overflow
-		if x < MaxFloat64/2 {
-			z := -Cos(x + x)
-			if s*c < 0 {
-				cc = z / ss
-			} else {
-				ss = z / cc
-			}
-		}
-		var z float64
-		if x > Two129 { // |x| > ~6.8056e+38
-			z = (1 / SqrtPi) * ss / Sqrt(x)
-		} else {
-			u := pzero(x)
-			v := qzero(x)
-			z = (1 / SqrtPi) * (u*ss + v*cc) / Sqrt(x)
-		}
-		return z // |x| >= 2.0
-	}
-	if x <= TwoM27 {
-		return U00 + (2/Pi)*Log(x) // |x| < ~7.4506e-9
-	}
-	z := x * x
-	u := U00 + z*(U01+z*(U02+z*(U03+z*(U04+z*(U05+z*U06)))))
-	v := 1 + z*(V01+z*(V02+z*(V03+z*V04)))
-	return u/v + (2/Pi)*J0(x)*Log(x) // ~7.4506e-9 < |x| < 2.0
-}
-
-// The asymptotic expansions of pzero is
-//      1 - 9/128 s**2 + 11025/98304 s**4 - ..., where s = 1/x.
-// For x >= 2, We approximate pzero by
-// 	pzero(x) = 1 + (R/S)
-// where  R = pR0 + pR1*s**2 + pR2*s**4 + ... + pR5*s**10
-// 	  S = 1 + pS0*s**2 + ... + pS4*s**10
-// and
-//      | pzero(x)-1-R/S | <= 2  ** ( -60.26)
-
-// for x in [inf, 8]=1/[0,0.125]
-var p0R8 = [6]float64{
-	0.00000000000000000000e+00,  // 0x0000000000000000
-	-7.03124999999900357484e-02, // 0xBFB1FFFFFFFFFD32
-	-8.08167041275349795626e+00, // 0xC02029D0B44FA779
-	-2.57063105679704847262e+02, // 0xC07011027B19E863
-	-2.48521641009428822144e+03, // 0xC0A36A6ECD4DCAFC
-	-5.25304380490729545272e+03, // 0xC0B4850B36CC643D
-}
-var p0S8 = [5]float64{
-	1.16534364619668181717e+02, // 0x405D223307A96751
-	3.83374475364121826715e+03, // 0x40ADF37D50596938
-	4.05978572648472545552e+04, // 0x40E3D2BB6EB6B05F
-	1.16752972564375915681e+05, // 0x40FC810F8F9FA9BD
-	4.76277284146730962675e+04, // 0x40E741774F2C49DC
-}
-
-// for x in [8,4.5454]=1/[0.125,0.22001]
-var p0R5 = [6]float64{
-	-1.14125464691894502584e-11, // 0xBDA918B147E495CC
-	-7.03124940873599280078e-02, // 0xBFB1FFFFE69AFBC6
-	-4.15961064470587782438e+00, // 0xC010A370F90C6BBF
-	-6.76747652265167261021e+01, // 0xC050EB2F5A7D1783
-	-3.31231299649172967747e+02, // 0xC074B3B36742CC63
-	-3.46433388365604912451e+02, // 0xC075A6EF28A38BD7
-}
-var p0S5 = [5]float64{
-	6.07539382692300335975e+01, // 0x404E60810C98C5DE
-	1.05125230595704579173e+03, // 0x40906D025C7E2864
-	5.97897094333855784498e+03, // 0x40B75AF88FBE1D60
-	9.62544514357774460223e+03, // 0x40C2CCB8FA76FA38
-	2.40605815922939109441e+03, // 0x40A2CC1DC70BE864
-}
-
-// for x in [4.547,2.8571]=1/[0.2199,0.35001]
-var p0R3 = [6]float64{
-	-2.54704601771951915620e-09, // 0xBE25E1036FE1AA86
-	-7.03119616381481654654e-02, // 0xBFB1FFF6F7C0E24B
-	-2.40903221549529611423e+00, // 0xC00345B2AEA48074
-	-2.19659774734883086467e+01, // 0xC035F74A4CB94E14
-	-5.80791704701737572236e+01, // 0xC04D0A22420A1A45
-	-3.14479470594888503854e+01, // 0xC03F72ACA892D80F
-}
-var p0S3 = [5]float64{
-	3.58560338055209726349e+01, // 0x4041ED9284077DD3
-	3.61513983050303863820e+02, // 0x40769839464A7C0E
-	1.19360783792111533330e+03, // 0x4092A66E6D1061D6
-	1.12799679856907414432e+03, // 0x40919FFCB8C39B7E
-	1.73580930813335754692e+02, // 0x4065B296FC379081
-}
-
-// for x in [2.8570,2]=1/[0.3499,0.5]
-var p0R2 = [6]float64{
-	-8.87534333032526411254e-08, // 0xBE77D316E927026D
-	-7.03030995483624743247e-02, // 0xBFB1FF62495E1E42
-	-1.45073846780952986357e+00, // 0xBFF736398A24A843
-	-7.63569613823527770791e+00, // 0xC01E8AF3EDAFA7F3
-	-1.11931668860356747786e+01, // 0xC02662E6C5246303
-	-3.23364579351335335033e+00, // 0xC009DE81AF8FE70F
-}
-var p0S2 = [5]float64{
-	2.22202997532088808441e+01, // 0x40363865908B5959
-	1.36206794218215208048e+02, // 0x4061069E0EE8878F
-	2.70470278658083486789e+02, // 0x4070E78642EA079B
-	1.53875394208320329881e+02, // 0x40633C033AB6FAFF
-	1.46576176948256193810e+01, // 0x402D50B344391809
-}
-
-func pzero(x float64) float64 {
-	var p *[6]float64
-	var q *[5]float64
-	if x >= 8 {
-		p = &p0R8
-		q = &p0S8
-	} else if x >= 4.5454 {
-		p = &p0R5
-		q = &p0S5
-	} else if x >= 2.8571 {
-		p = &p0R3
-		q = &p0S3
-	} else if x >= 2 {
-		p = &p0R2
-		q = &p0S2
-	}
-	z := 1 / (x * x)
-	r := p[0] + z*(p[1]+z*(p[2]+z*(p[3]+z*(p[4]+z*p[5]))))
-	s := 1 + z*(q[0]+z*(q[1]+z*(q[2]+z*(q[3]+z*q[4]))))
-	return 1 + r/s
-}
-
-// For x >= 8, the asymptotic expansions of qzero is
-//      -1/8 s + 75/1024 s**3 - ..., where s = 1/x.
-// We approximate pzero by
-//      qzero(x) = s*(-1.25 + (R/S))
-// where R = qR0 + qR1*s**2 + qR2*s**4 + ... + qR5*s**10
-//       S = 1 + qS0*s**2 + ... + qS5*s**12
-// and
-//      | qzero(x)/s +1.25-R/S | <= 2**(-61.22)
-
-// for x in [inf, 8]=1/[0,0.125]
-var q0R8 = [6]float64{
-	0.00000000000000000000e+00, // 0x0000000000000000
-	7.32421874999935051953e-02, // 0x3FB2BFFFFFFFFE2C
-	1.17682064682252693899e+01, // 0x402789525BB334D6
-	5.57673380256401856059e+02, // 0x40816D6315301825
-	8.85919720756468632317e+03, // 0x40C14D993E18F46D
-	3.70146267776887834771e+04, // 0x40E212D40E901566
-}
-var q0S8 = [6]float64{
-	1.63776026895689824414e+02,  // 0x406478D5365B39BC
-	8.09834494656449805916e+03,  // 0x40BFA2584E6B0563
-	1.42538291419120476348e+05,  // 0x4101665254D38C3F
-	8.03309257119514397345e+05,  // 0x412883DA83A52B43
-	8.40501579819060512818e+05,  // 0x4129A66B28DE0B3D
-	-3.43899293537866615225e+05, // 0xC114FD6D2C9530C5
-}
-
-// for x in [8,4.5454]=1/[0.125,0.22001]
-var q0R5 = [6]float64{
-	1.84085963594515531381e-11, // 0x3DB43D8F29CC8CD9
-	7.32421766612684765896e-02, // 0x3FB2BFFFD172B04C
-	5.83563508962056953777e+00, // 0x401757B0B9953DD3
-	1.35111577286449829671e+02, // 0x4060E3920A8788E9
-	1.02724376596164097464e+03, // 0x40900CF99DC8C481
-	1.98997785864605384631e+03, // 0x409F17E953C6E3A6
-}
-var q0S5 = [6]float64{
-	8.27766102236537761883e+01,  // 0x4054B1B3FB5E1543
-	2.07781416421392987104e+03,  // 0x40A03BA0DA21C0CE
-	1.88472887785718085070e+04,  // 0x40D267D27B591E6D
-	5.67511122894947329769e+04,  // 0x40EBB5E397E02372
-	3.59767538425114471465e+04,  // 0x40E191181F7A54A0
-	-5.35434275601944773371e+03, // 0xC0B4EA57BEDBC609
-}
-
-// for x in [4.547,2.8571]=1/[0.2199,0.35001]
-var q0R3 = [6]float64{
-	4.37741014089738620906e-09, // 0x3E32CD036ADECB82
-	7.32411180042911447163e-02, // 0x3FB2BFEE0E8D0842
-	3.34423137516170720929e+00, // 0x400AC0FC61149CF5
-	4.26218440745412650017e+01, // 0x40454F98962DAEDD
-	1.70808091340565596283e+02, // 0x406559DBE25EFD1F
-	1.66733948696651168575e+02, // 0x4064D77C81FA21E0
-}
-var q0S3 = [6]float64{
-	4.87588729724587182091e+01,  // 0x40486122BFE343A6
-	7.09689221056606015736e+02,  // 0x40862D8386544EB3
-	3.70414822620111362994e+03,  // 0x40ACF04BE44DFC63
-	6.46042516752568917582e+03,  // 0x40B93C6CD7C76A28
-	2.51633368920368957333e+03,  // 0x40A3A8AAD94FB1C0
-	-1.49247451836156386662e+02, // 0xC062A7EB201CF40F
-}
-
-// for x in [2.8570,2]=1/[0.3499,0.5]
-var q0R2 = [6]float64{
-	1.50444444886983272379e-07, // 0x3E84313B54F76BDB
-	7.32234265963079278272e-02, // 0x3FB2BEC53E883E34
-	1.99819174093815998816e+00, // 0x3FFFF897E727779C
-	1.44956029347885735348e+01, // 0x402CFDBFAAF96FE5
-	3.16662317504781540833e+01, // 0x403FAA8E29FBDC4A
-	1.62527075710929267416e+01, // 0x403040B171814BB4
-}
-var q0S2 = [6]float64{
-	3.03655848355219184498e+01,  // 0x403E5D96F7C07AED
-	2.69348118608049844624e+02,  // 0x4070D591E4D14B40
-	8.44783757595320139444e+02,  // 0x408A664522B3BF22
-	8.82935845112488550512e+02,  // 0x408B977C9C5CC214
-	2.12666388511798828631e+02,  // 0x406A95530E001365
-	-5.31095493882666946917e+00, // 0xC0153E6AF8B32931
-}
-
-func qzero(x float64) float64 {
-	var p, q *[6]float64
-	if x >= 8 {
-		p = &q0R8
-		q = &q0S8
-	} else if x >= 4.5454 {
-		p = &q0R5
-		q = &q0S5
-	} else if x >= 2.8571 {
-		p = &q0R3
-		q = &q0S3
-	} else if x >= 2 {
-		p = &q0R2
-		q = &q0S2
-	}
-	z := 1 / (x * x)
-	r := p[0] + z*(p[1]+z*(p[2]+z*(p[3]+z*(p[4]+z*p[5]))))
-	s := 1 + z*(q[0]+z*(q[1]+z*(q[2]+z*(q[3]+z*(q[4]+z*q[5])))))
-	return (-0.125 + r/s) / x
-}
diff --git a/contrib/go/_std_1.18/src/math/j1.go b/contrib/go/_std_1.18/src/math/j1.go
deleted file mode 100644
index 7c7d279730..0000000000
--- a/contrib/go/_std_1.18/src/math/j1.go
+++ /dev/null
@@ -1,422 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-/*
-	Bessel function of the first and second kinds of order one.
-*/
-
-// The original C code and the long comment below are
-// from FreeBSD's /usr/src/lib/msun/src/e_j1.c and
-// came with this notice. The go code is a simplified
-// version of the original C.
-//
-// ====================================================
-// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
-//
-// Developed at SunPro, a Sun Microsystems, Inc. business.
-// Permission to use, copy, modify, and distribute this
-// software is freely granted, provided that this notice
-// is preserved.
-// ====================================================
-//
-// __ieee754_j1(x), __ieee754_y1(x)
-// Bessel function of the first and second kinds of order one.
-// Method -- j1(x):
-//      1. For tiny x, we use j1(x) = x/2 - x**3/16 + x**5/384 - ...
-//      2. Reduce x to |x| since j1(x)=-j1(-x),  and
-//         for x in (0,2)
-//              j1(x) = x/2 + x*z*R0/S0,  where z = x*x;
-//         (precision:  |j1/x - 1/2 - R0/S0 |<2**-61.51 )
-//         for x in (2,inf)
-//              j1(x) = sqrt(2/(pi*x))*(p1(x)*cos(x1)-q1(x)*sin(x1))
-//              y1(x) = sqrt(2/(pi*x))*(p1(x)*sin(x1)+q1(x)*cos(x1))
-//         where x1 = x-3*pi/4. It is better to compute sin(x1),cos(x1)
-//         as follow:
-//              cos(x1) =  cos(x)cos(3pi/4)+sin(x)sin(3pi/4)
-//                      =  1/sqrt(2) * (sin(x) - cos(x))
-//              sin(x1) =  sin(x)cos(3pi/4)-cos(x)sin(3pi/4)
-//                      = -1/sqrt(2) * (sin(x) + cos(x))
-//         (To avoid cancellation, use
-//              sin(x) +- cos(x) = -cos(2x)/(sin(x) -+ cos(x))
-//         to compute the worse one.)
-//
-//      3 Special cases
-//              j1(nan)= nan
-//              j1(0) = 0
-//              j1(inf) = 0
-//
-// Method -- y1(x):
-//      1. screen out x<=0 cases: y1(0)=-inf, y1(x<0)=NaN
-//      2. For x<2.
-//         Since
-//              y1(x) = 2/pi*(j1(x)*(ln(x/2)+Euler)-1/x-x/2+5/64*x**3-...)
-//         therefore y1(x)-2/pi*j1(x)*ln(x)-1/x is an odd function.
-//         We use the following function to approximate y1,
-//              y1(x) = x*U(z)/V(z) + (2/pi)*(j1(x)*ln(x)-1/x), z= x**2
-//         where for x in [0,2] (abs err less than 2**-65.89)
-//              U(z) = U0[0] + U0[1]*z + ... + U0[4]*z**4
-//              V(z) = 1  + v0[0]*z + ... + v0[4]*z**5
-//         Note: For tiny x, 1/x dominate y1 and hence
-//              y1(tiny) = -2/pi/tiny, (choose tiny<2**-54)
-//      3. For x>=2.
-//               y1(x) = sqrt(2/(pi*x))*(p1(x)*sin(x1)+q1(x)*cos(x1))
-//         where x1 = x-3*pi/4. It is better to compute sin(x1),cos(x1)
-//         by method mentioned above.
-
-// J1 returns the order-one Bessel function of the first kind.
-//
-// Special cases are:
-//	J1(±Inf) = 0
-//	J1(NaN) = NaN
-func J1(x float64) float64 {
-	const (
-		TwoM27 = 1.0 / (1 << 27) // 2**-27 0x3e40000000000000
-		Two129 = 1 << 129        // 2**129 0x4800000000000000
-		// R0/S0 on [0, 2]
-		R00 = -6.25000000000000000000e-02 // 0xBFB0000000000000
-		R01 = 1.40705666955189706048e-03  // 0x3F570D9F98472C61
-		R02 = -1.59955631084035597520e-05 // 0xBEF0C5C6BA169668
-		R03 = 4.96727999609584448412e-08  // 0x3E6AAAFA46CA0BD9
-		S01 = 1.91537599538363460805e-02  // 0x3F939D0B12637E53
-		S02 = 1.85946785588630915560e-04  // 0x3F285F56B9CDF664
-		S03 = 1.17718464042623683263e-06  // 0x3EB3BFF8333F8498
-		S04 = 5.04636257076217042715e-09  // 0x3E35AC88C97DFF2C
-		S05 = 1.23542274426137913908e-11  // 0x3DAB2ACFCFB97ED8
-	)
-	// special cases
-	switch {
-	case IsNaN(x):
-		return x
-	case IsInf(x, 0) || x == 0:
-		return 0
-	}
-
-	sign := false
-	if x < 0 {
-		x = -x
-		sign = true
-	}
-	if x >= 2 {
-		s, c := Sincos(x)
-		ss := -s - c
-		cc := s - c
-
-		// make sure x+x does not overflow
-		if x < MaxFloat64/2 {
-			z := Cos(x + x)
-			if s*c > 0 {
-				cc = z / ss
-			} else {
-				ss = z / cc
-			}
-		}
-
-		// j1(x) = 1/sqrt(pi) * (P(1,x)*cc - Q(1,x)*ss) / sqrt(x)
-		// y1(x) = 1/sqrt(pi) * (P(1,x)*ss + Q(1,x)*cc) / sqrt(x)
-
-		var z float64
-		if x > Two129 {
-			z = (1 / SqrtPi) * cc / Sqrt(x)
-		} else {
-			u := pone(x)
-			v := qone(x)
-			z = (1 / SqrtPi) * (u*cc - v*ss) / Sqrt(x)
-		}
-		if sign {
-			return -z
-		}
-		return z
-	}
-	if x < TwoM27 { // |x|<2**-27
-		return 0.5 * x // inexact if x!=0 necessary
-	}
-	z := x * x
-	r := z * (R00 + z*(R01+z*(R02+z*R03)))
-	s := 1.0 + z*(S01+z*(S02+z*(S03+z*(S04+z*S05))))
-	r *= x
-	z = 0.5*x + r/s
-	if sign {
-		return -z
-	}
-	return z
-}
-
-// Y1 returns the order-one Bessel function of the second kind.
-//
-// Special cases are:
-//	Y1(+Inf) = 0
-//	Y1(0) = -Inf
-//	Y1(x < 0) = NaN
-//	Y1(NaN) = NaN
-func Y1(x float64) float64 {
-	const (
-		TwoM54 = 1.0 / (1 << 54)             // 2**-54 0x3c90000000000000
-		Two129 = 1 << 129                    // 2**129 0x4800000000000000
-		U00    = -1.96057090646238940668e-01 // 0xBFC91866143CBC8A
-		U01    = 5.04438716639811282616e-02  // 0x3FA9D3C776292CD1
-		U02    = -1.91256895875763547298e-03 // 0xBF5F55E54844F50F
-		U03    = 2.35252600561610495928e-05  // 0x3EF8AB038FA6B88E
-		U04    = -9.19099158039878874504e-08 // 0xBE78AC00569105B8
-		V00    = 1.99167318236649903973e-02  // 0x3F94650D3F4DA9F0
-		V01    = 2.02552581025135171496e-04  // 0x3F2A8C896C257764
-		V02    = 1.35608801097516229404e-06  // 0x3EB6C05A894E8CA6
-		V03    = 6.22741452364621501295e-09  // 0x3E3ABF1D5BA69A86
-		V04    = 1.66559246207992079114e-11  // 0x3DB25039DACA772A
-	)
-	// special cases
-	switch {
-	case x < 0 || IsNaN(x):
-		return NaN()
-	case IsInf(x, 1):
-		return 0
-	case x == 0:
-		return Inf(-1)
-	}
-
-	if x >= 2 {
-		s, c := Sincos(x)
-		ss := -s - c
-		cc := s - c
-
-		// make sure x+x does not overflow
-		if x < MaxFloat64/2 {
-			z := Cos(x + x)
-			if s*c > 0 {
-				cc = z / ss
-			} else {
-				ss = z / cc
-			}
-		}
-		// y1(x) = sqrt(2/(pi*x))*(p1(x)*sin(x0)+q1(x)*cos(x0))
-		// where x0 = x-3pi/4
-		//     Better formula:
-		//         cos(x0) = cos(x)cos(3pi/4)+sin(x)sin(3pi/4)
-		//                 =  1/sqrt(2) * (sin(x) - cos(x))
-		//         sin(x0) = sin(x)cos(3pi/4)-cos(x)sin(3pi/4)
-		//                 = -1/sqrt(2) * (cos(x) + sin(x))
-		// To avoid cancellation, use
-		//     sin(x) +- cos(x) = -cos(2x)/(sin(x) -+ cos(x))
-		// to compute the worse one.
-
-		var z float64
-		if x > Two129 {
-			z = (1 / SqrtPi) * ss / Sqrt(x)
-		} else {
-			u := pone(x)
-			v := qone(x)
-			z = (1 / SqrtPi) * (u*ss + v*cc) / Sqrt(x)
-		}
-		return z
-	}
-	if x <= TwoM54 { // x < 2**-54
-		return -(2 / Pi) / x
-	}
-	z := x * x
-	u := U00 + z*(U01+z*(U02+z*(U03+z*U04)))
-	v := 1 + z*(V00+z*(V01+z*(V02+z*(V03+z*V04))))
-	return x*(u/v) + (2/Pi)*(J1(x)*Log(x)-1/x)
-}
-
-// For x >= 8, the asymptotic expansions of pone is
-//      1 + 15/128 s**2 - 4725/2**15 s**4 - ..., where s = 1/x.
-// We approximate pone by
-//      pone(x) = 1 + (R/S)
-// where R = pr0 + pr1*s**2 + pr2*s**4 + ... + pr5*s**10
-//       S = 1 + ps0*s**2 + ... + ps4*s**10
-// and
-//      | pone(x)-1-R/S | <= 2**(-60.06)
-
-// for x in [inf, 8]=1/[0,0.125]
-var p1R8 = [6]float64{
-	0.00000000000000000000e+00, // 0x0000000000000000
-	1.17187499999988647970e-01, // 0x3FBDFFFFFFFFFCCE
-	1.32394806593073575129e+01, // 0x402A7A9D357F7FCE
-	4.12051854307378562225e+02, // 0x4079C0D4652EA590
-	3.87474538913960532227e+03, // 0x40AE457DA3A532CC
-	7.91447954031891731574e+03, // 0x40BEEA7AC32782DD
-}
-var p1S8 = [5]float64{
-	1.14207370375678408436e+02, // 0x405C8D458E656CAC
-	3.65093083420853463394e+03, // 0x40AC85DC964D274F
-	3.69562060269033463555e+04, // 0x40E20B8697C5BB7F
-	9.76027935934950801311e+04, // 0x40F7D42CB28F17BB
-	3.08042720627888811578e+04, // 0x40DE1511697A0B2D
-}
-
-// for x in [8,4.5454] = 1/[0.125,0.22001]
-var p1R5 = [6]float64{
-	1.31990519556243522749e-11, // 0x3DAD0667DAE1CA7D
-	1.17187493190614097638e-01, // 0x3FBDFFFFE2C10043
-	6.80275127868432871736e+00, // 0x401B36046E6315E3
-	1.08308182990189109773e+02, // 0x405B13B9452602ED
-	5.17636139533199752805e+02, // 0x40802D16D052D649
-	5.28715201363337541807e+02, // 0x408085B8BB7E0CB7
-}
-var p1S5 = [5]float64{
-	5.92805987221131331921e+01, // 0x404DA3EAA8AF633D
-	9.91401418733614377743e+02, // 0x408EFB361B066701
-	5.35326695291487976647e+03, // 0x40B4E9445706B6FB
-	7.84469031749551231769e+03, // 0x40BEA4B0B8A5BB15
-	1.50404688810361062679e+03, // 0x40978030036F5E51
-}
-
-// for x in[4.5453,2.8571] = 1/[0.2199,0.35001]
-var p1R3 = [6]float64{
-	3.02503916137373618024e-09, // 0x3E29FC21A7AD9EDD
-	1.17186865567253592491e-01, // 0x3FBDFFF55B21D17B
-	3.93297750033315640650e+00, // 0x400F76BCE85EAD8A
-	3.51194035591636932736e+01, // 0x40418F489DA6D129
-	9.10550110750781271918e+01, // 0x4056C3854D2C1837
-	4.85590685197364919645e+01, // 0x4048478F8EA83EE5
-}
-var p1S3 = [5]float64{
-	3.47913095001251519989e+01, // 0x40416549A134069C
-	3.36762458747825746741e+02, // 0x40750C3307F1A75F
-	1.04687139975775130551e+03, // 0x40905B7C5037D523
-	8.90811346398256432622e+02, // 0x408BD67DA32E31E9
-	1.03787932439639277504e+02, // 0x4059F26D7C2EED53
-}
-
-// for x in [2.8570,2] = 1/[0.3499,0.5]
-var p1R2 = [6]float64{
-	1.07710830106873743082e-07, // 0x3E7CE9D4F65544F4
-	1.17176219462683348094e-01, // 0x3FBDFF42BE760D83
-	2.36851496667608785174e+00, // 0x4002F2B7F98FAEC0
-	1.22426109148261232917e+01, // 0x40287C377F71A964
-	1.76939711271687727390e+01, // 0x4031B1A8177F8EE2
-	5.07352312588818499250e+00, // 0x40144B49A574C1FE
-}
-var p1S2 = [5]float64{
-	2.14364859363821409488e+01, // 0x40356FBD8AD5ECDC
-	1.25290227168402751090e+02, // 0x405F529314F92CD5
-	2.32276469057162813669e+02, // 0x406D08D8D5A2DBD9
-	1.17679373287147100768e+02, // 0x405D6B7ADA1884A9
-	8.36463893371618283368e+00, // 0x4020BAB1F44E5192
-}
-
-func pone(x float64) float64 {
-	var p *[6]float64
-	var q *[5]float64
-	if x >= 8 {
-		p = &p1R8
-		q = &p1S8
-	} else if x >= 4.5454 {
-		p = &p1R5
-		q = &p1S5
-	} else if x >= 2.8571 {
-		p = &p1R3
-		q = &p1S3
-	} else if x >= 2 {
-		p = &p1R2
-		q = &p1S2
-	}
-	z := 1 / (x * x)
-	r := p[0] + z*(p[1]+z*(p[2]+z*(p[3]+z*(p[4]+z*p[5]))))
-	s := 1.0 + z*(q[0]+z*(q[1]+z*(q[2]+z*(q[3]+z*q[4]))))
-	return 1 + r/s
-}
-
-// For x >= 8, the asymptotic expansions of qone is
-//      3/8 s - 105/1024 s**3 - ..., where s = 1/x.
-// We approximate qone by
-//      qone(x) = s*(0.375 + (R/S))
-// where R = qr1*s**2 + qr2*s**4 + ... + qr5*s**10
-//       S = 1 + qs1*s**2 + ... + qs6*s**12
-// and
-//      | qone(x)/s -0.375-R/S | <= 2**(-61.13)
-
-// for x in [inf, 8] = 1/[0,0.125]
-var q1R8 = [6]float64{
-	0.00000000000000000000e+00,  // 0x0000000000000000
-	-1.02539062499992714161e-01, // 0xBFBA3FFFFFFFFDF3
-	-1.62717534544589987888e+01, // 0xC0304591A26779F7
-	-7.59601722513950107896e+02, // 0xC087BCD053E4B576
-	-1.18498066702429587167e+04, // 0xC0C724E740F87415
-	-4.84385124285750353010e+04, // 0xC0E7A6D065D09C6A
-}
-var q1S8 = [6]float64{
-	1.61395369700722909556e+02,  // 0x40642CA6DE5BCDE5
-	7.82538599923348465381e+03,  // 0x40BE9162D0D88419
-	1.33875336287249578163e+05,  // 0x4100579AB0B75E98
-	7.19657723683240939863e+05,  // 0x4125F65372869C19
-	6.66601232617776375264e+05,  // 0x412457D27719AD5C
-	-2.94490264303834643215e+05, // 0xC111F9690EA5AA18
-}
-
-// for x in [8,4.5454] = 1/[0.125,0.22001]
-var q1R5 = [6]float64{
-	-2.08979931141764104297e-11, // 0xBDB6FA431AA1A098
-	-1.02539050241375426231e-01, // 0xBFBA3FFFCB597FEF
-	-8.05644828123936029840e+00, // 0xC0201CE6CA03AD4B
-	-1.83669607474888380239e+02, // 0xC066F56D6CA7B9B0
-	-1.37319376065508163265e+03, // 0xC09574C66931734F
-	-2.61244440453215656817e+03, // 0xC0A468E388FDA79D
-}
-var q1S5 = [6]float64{
-	8.12765501384335777857e+01,  // 0x405451B2FF5A11B2
-	1.99179873460485964642e+03,  // 0x409F1F31E77BF839
-	1.74684851924908907677e+04,  // 0x40D10F1F0D64CE29
-	4.98514270910352279316e+04,  // 0x40E8576DAABAD197
-	2.79480751638918118260e+04,  // 0x40DB4B04CF7C364B
-	-4.71918354795128470869e+03, // 0xC0B26F2EFCFFA004
-}
-
-// for x in [4.5454,2.8571] = 1/[0.2199,0.35001] ???
-var q1R3 = [6]float64{
-	-5.07831226461766561369e-09, // 0xBE35CFA9D38FC84F
-	-1.02537829820837089745e-01, // 0xBFBA3FEB51AEED54
-	-4.61011581139473403113e+00, // 0xC01270C23302D9FF
-	-5.78472216562783643212e+01, // 0xC04CEC71C25D16DA
-	-2.28244540737631695038e+02, // 0xC06C87D34718D55F
-	-2.19210128478909325622e+02, // 0xC06B66B95F5C1BF6
-}
-var q1S3 = [6]float64{
-	4.76651550323729509273e+01,  // 0x4047D523CCD367E4
-	6.73865112676699709482e+02,  // 0x40850EEBC031EE3E
-	3.38015286679526343505e+03,  // 0x40AA684E448E7C9A
-	5.54772909720722782367e+03,  // 0x40B5ABBAA61D54A6
-	1.90311919338810798763e+03,  // 0x409DBC7A0DD4DF4B
-	-1.35201191444307340817e+02, // 0xC060E670290A311F
-}
-
-// for x in [2.8570,2] = 1/[0.3499,0.5]
-var q1R2 = [6]float64{
-	-1.78381727510958865572e-07, // 0xBE87F12644C626D2
-	-1.02517042607985553460e-01, // 0xBFBA3E8E9148B010
-	-2.75220568278187460720e+00, // 0xC006048469BB4EDA
-	-1.96636162643703720221e+01, // 0xC033A9E2C168907F
-	-4.23253133372830490089e+01, // 0xC04529A3DE104AAA
-	-2.13719211703704061733e+01, // 0xC0355F3639CF6E52
-}
-var q1S2 = [6]float64{
-	2.95333629060523854548e+01,  // 0x403D888A78AE64FF
-	2.52981549982190529136e+02,  // 0x406F9F68DB821CBA
-	7.57502834868645436472e+02,  // 0x4087AC05CE49A0F7
-	7.39393205320467245656e+02,  // 0x40871B2548D4C029
-	1.55949003336666123687e+02,  // 0x40637E5E3C3ED8D4
-	-4.95949898822628210127e+00, // 0xC013D686E71BE86B
-}
-
-func qone(x float64) float64 {
-	var p, q *[6]float64
-	if x >= 8 {
-		p = &q1R8
-		q = &q1S8
-	} else if x >= 4.5454 {
-		p = &q1R5
-		q = &q1S5
-	} else if x >= 2.8571 {
-		p = &q1R3
-		q = &q1S3
-	} else if x >= 2 {
-		p = &q1R2
-		q = &q1S2
-	}
-	z := 1 / (x * x)
-	r := p[0] + z*(p[1]+z*(p[2]+z*(p[3]+z*(p[4]+z*p[5]))))
-	s := 1 + z*(q[0]+z*(q[1]+z*(q[2]+z*(q[3]+z*(q[4]+z*q[5])))))
-	return (0.375 + r/s) / x
-}
diff --git a/contrib/go/_std_1.18/src/math/jn.go b/contrib/go/_std_1.18/src/math/jn.go
deleted file mode 100644
index b1aca8ff6b..0000000000
--- a/contrib/go/_std_1.18/src/math/jn.go
+++ /dev/null
@@ -1,304 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-/*
-	Bessel function of the first and second kinds of order n.
-*/
-
-// The original C code and the long comment below are
-// from FreeBSD's /usr/src/lib/msun/src/e_jn.c and
-// came with this notice. The go code is a simplified
-// version of the original C.
-//
-// ====================================================
-// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
-//
-// Developed at SunPro, a Sun Microsystems, Inc. business.
-// Permission to use, copy, modify, and distribute this
-// software is freely granted, provided that this notice
-// is preserved.
-// ====================================================
-//
-// __ieee754_jn(n, x), __ieee754_yn(n, x)
-// floating point Bessel's function of the 1st and 2nd kind
-// of order n
-//
-// Special cases:
-//      y0(0)=y1(0)=yn(n,0) = -inf with division by zero signal;
-//      y0(-ve)=y1(-ve)=yn(n,-ve) are NaN with invalid signal.
-// Note 2. About jn(n,x), yn(n,x)
-//      For n=0, j0(x) is called,
-//      for n=1, j1(x) is called,
-//      for n<x, forward recursion is used starting
-//      from values of j0(x) and j1(x).
-//      for n>x, a continued fraction approximation to
-//      j(n,x)/j(n-1,x) is evaluated and then backward
-//      recursion is used starting from a supposed value
-//      for j(n,x). The resulting value of j(0,x) is
-//      compared with the actual value to correct the
-//      supposed value of j(n,x).
-//
-//      yn(n,x) is similar in all respects, except
-//      that forward recursion is used for all
-//      values of n>1.
-
-// Jn returns the order-n Bessel function of the first kind.
-//
-// Special cases are:
-//	Jn(n, ±Inf) = 0
-//	Jn(n, NaN) = NaN
-func Jn(n int, x float64) float64 {
-	const (
-		TwoM29 = 1.0 / (1 << 29) // 2**-29 0x3e10000000000000
-		Two302 = 1 << 302        // 2**302 0x52D0000000000000
-	)
-	// special cases
-	switch {
-	case IsNaN(x):
-		return x
-	case IsInf(x, 0):
-		return 0
-	}
-	// J(-n, x) = (-1)**n * J(n, x), J(n, -x) = (-1)**n * J(n, x)
-	// Thus, J(-n, x) = J(n, -x)
-
-	if n == 0 {
-		return J0(x)
-	}
-	if x == 0 {
-		return 0
-	}
-	if n < 0 {
-		n, x = -n, -x
-	}
-	if n == 1 {
-		return J1(x)
-	}
-	sign := false
-	if x < 0 {
-		x = -x
-		if n&1 == 1 {
-			sign = true // odd n and negative x
-		}
-	}
-	var b float64
-	if float64(n) <= x {
-		// Safe to use J(n+1,x)=2n/x *J(n,x)-J(n-1,x)
-		if x >= Two302 { // x > 2**302
-
-			// (x >> n**2)
-			//          Jn(x) = cos(x-(2n+1)*pi/4)*sqrt(2/x*pi)
-			//          Yn(x) = sin(x-(2n+1)*pi/4)*sqrt(2/x*pi)
-			//          Let s=sin(x), c=cos(x),
-			//              xn=x-(2n+1)*pi/4, sqt2 = sqrt(2),then
-			//
-			//                 n    sin(xn)*sqt2    cos(xn)*sqt2
-			//              ----------------------------------
-			//                 0     s-c             c+s
-			//                 1    -s-c            -c+s
-			//                 2    -s+c            -c-s
-			//                 3     s+c             c-s
-
-			var temp float64
-			switch s, c := Sincos(x); n & 3 {
-			case 0:
-				temp = c + s
-			case 1:
-				temp = -c + s
-			case 2:
-				temp = -c - s
-			case 3:
-				temp = c - s
-			}
-			b = (1 / SqrtPi) * temp / Sqrt(x)
-		} else {
-			b = J1(x)
-			for i, a := 1, J0(x); i < n; i++ {
-				a, b = b, b*(float64(i+i)/x)-a // avoid underflow
-			}
-		}
-	} else {
-		if x < TwoM29 { // x < 2**-29
-			// x is tiny, return the first Taylor expansion of J(n,x)
-			// J(n,x) = 1/n!*(x/2)**n  - ...
-
-			if n > 33 { // underflow
-				b = 0
-			} else {
-				temp := x * 0.5
-				b = temp
-				a := 1.0
-				for i := 2; i <= n; i++ {
-					a *= float64(i) // a = n!
-					b *= temp       // b = (x/2)**n
-				}
-				b /= a
-			}
-		} else {
-			// use backward recurrence
-			//                      x      x**2      x**2
-			//  J(n,x)/J(n-1,x) =  ----   ------   ------   .....
-			//                      2n  - 2(n+1) - 2(n+2)
-			//
-			//                      1      1        1
-			//  (for large x)   =  ----  ------   ------   .....
-			//                      2n   2(n+1)   2(n+2)
-			//                      -- - ------ - ------ -
-			//                       x     x         x
-			//
-			// Let w = 2n/x and h=2/x, then the above quotient
-			// is equal to the continued fraction:
-			//                  1
-			//      = -----------------------
-			//                     1
-			//         w - -----------------
-			//                        1
-			//              w+h - ---------
-			//                     w+2h - ...
-			//
-			// To determine how many terms needed, let
-			// Q(0) = w, Q(1) = w(w+h) - 1,
-			// Q(k) = (w+k*h)*Q(k-1) - Q(k-2),
-			// When Q(k) > 1e4	good for single
-			// When Q(k) > 1e9	good for double
-			// When Q(k) > 1e17	good for quadruple
-
-			// determine k
-			w := float64(n+n) / x
-			h := 2 / x
-			q0 := w
-			z := w + h
-			q1 := w*z - 1
-			k := 1
-			for q1 < 1e9 {
-				k++
-				z += h
-				q0, q1 = q1, z*q1-q0
-			}
-			m := n + n
-			t := 0.0
-			for i := 2 * (n + k); i >= m; i -= 2 {
-				t = 1 / (float64(i)/x - t)
-			}
-			a := t
-			b = 1
-			//  estimate log((2/x)**n*n!) = n*log(2/x)+n*ln(n)
-			//  Hence, if n*(log(2n/x)) > ...
-			//  single 8.8722839355e+01
-			//  double 7.09782712893383973096e+02
-			//  long double 1.1356523406294143949491931077970765006170e+04
-			//  then recurrent value may overflow and the result is
-			//  likely underflow to zero
-
-			tmp := float64(n)
-			v := 2 / x
-			tmp = tmp * Log(Abs(v*tmp))
-			if tmp < 7.09782712893383973096e+02 {
-				for i := n - 1; i > 0; i-- {
-					di := float64(i + i)
-					a, b = b, b*di/x-a
-				}
-			} else {
-				for i := n - 1; i > 0; i-- {
-					di := float64(i + i)
-					a, b = b, b*di/x-a
-					// scale b to avoid spurious overflow
-					if b > 1e100 {
-						a /= b
-						t /= b
-						b = 1
-					}
-				}
-			}
-			b = t * J0(x) / b
-		}
-	}
-	if sign {
-		return -b
-	}
-	return b
-}
-
-// Yn returns the order-n Bessel function of the second kind.
-//
-// Special cases are:
-//	Yn(n, +Inf) = 0
-//	Yn(n ≥ 0, 0) = -Inf
-//	Yn(n < 0, 0) = +Inf if n is odd, -Inf if n is even
-//	Yn(n, x < 0) = NaN
-//	Yn(n, NaN) = NaN
-func Yn(n int, x float64) float64 {
-	const Two302 = 1 << 302 // 2**302 0x52D0000000000000
-	// special cases
-	switch {
-	case x < 0 || IsNaN(x):
-		return NaN()
-	case IsInf(x, 1):
-		return 0
-	}
-
-	if n == 0 {
-		return Y0(x)
-	}
-	if x == 0 {
-		if n < 0 && n&1 == 1 {
-			return Inf(1)
-		}
-		return Inf(-1)
-	}
-	sign := false
-	if n < 0 {
-		n = -n
-		if n&1 == 1 {
-			sign = true // sign true if n < 0 && |n| odd
-		}
-	}
-	if n == 1 {
-		if sign {
-			return -Y1(x)
-		}
-		return Y1(x)
-	}
-	var b float64
-	if x >= Two302 { // x > 2**302
-		// (x >> n**2)
-		//	    Jn(x) = cos(x-(2n+1)*pi/4)*sqrt(2/x*pi)
-		//	    Yn(x) = sin(x-(2n+1)*pi/4)*sqrt(2/x*pi)
-		//	    Let s=sin(x), c=cos(x),
-		//		xn=x-(2n+1)*pi/4, sqt2 = sqrt(2),then
-		//
-		//		   n	sin(xn)*sqt2	cos(xn)*sqt2
-		//		----------------------------------
-		//		   0	 s-c		 c+s
-		//		   1	-s-c 		-c+s
-		//		   2	-s+c		-c-s
-		//		   3	 s+c		 c-s
-
-		var temp float64
-		switch s, c := Sincos(x); n & 3 {
-		case 0:
-			temp = s - c
-		case 1:
-			temp = -s - c
-		case 2:
-			temp = -s + c
-		case 3:
-			temp = s + c
-		}
-		b = (1 / SqrtPi) * temp / Sqrt(x)
-	} else {
-		a := Y0(x)
-		b = Y1(x)
-		// quit if b is -inf
-		for i := 1; i < n && !IsInf(b, -1); i++ {
-			a, b = b, (float64(i+i)/x)*b-a
-		}
-	}
-	if sign {
-		return -b
-	}
-	return b
-}
diff --git a/contrib/go/_std_1.18/src/math/ldexp.go b/contrib/go/_std_1.18/src/math/ldexp.go
deleted file mode 100644
index 55c82f1e84..0000000000
--- a/contrib/go/_std_1.18/src/math/ldexp.go
+++ /dev/null
@@ -1,50 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-// Ldexp is the inverse of Frexp.
-// It returns frac × 2**exp.
-//
-// Special cases are:
-//	Ldexp(±0, exp) = ±0
-//	Ldexp(±Inf, exp) = ±Inf
-//	Ldexp(NaN, exp) = NaN
-func Ldexp(frac float64, exp int) float64 {
-	if haveArchLdexp {
-		return archLdexp(frac, exp)
-	}
-	return ldexp(frac, exp)
-}
-
-func ldexp(frac float64, exp int) float64 {
-	// special cases
-	switch {
-	case frac == 0:
-		return frac // correctly return -0
-	case IsInf(frac, 0) || IsNaN(frac):
-		return frac
-	}
-	frac, e := normalize(frac)
-	exp += e
-	x := Float64bits(frac)
-	exp += int(x>>shift)&mask - bias
-	if exp < -1075 {
-		return Copysign(0, frac) // underflow
-	}
-	if exp > 1023 { // overflow
-		if frac < 0 {
-			return Inf(-1)
-		}
-		return Inf(1)
-	}
-	var m float64 = 1
-	if exp < -1022 { // denormal
-		exp += 53
-		m = 1.0 / (1 << 53) // 2**-53
-	}
-	x &^= mask << shift
-	x |= uint64(exp+bias) << shift
-	return m * Float64frombits(x)
-}
diff --git a/contrib/go/_std_1.18/src/math/lgamma.go b/contrib/go/_std_1.18/src/math/lgamma.go
deleted file mode 100644
index 7af5871744..0000000000
--- a/contrib/go/_std_1.18/src/math/lgamma.go
+++ /dev/null
@@ -1,365 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-/*
-	Floating-point logarithm of the Gamma function.
-*/
-
-// The original C code and the long comment below are
-// from FreeBSD's /usr/src/lib/msun/src/e_lgamma_r.c and
-// came with this notice. The go code is a simplified
-// version of the original C.
-//
-// ====================================================
-// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
-//
-// Developed at SunPro, a Sun Microsystems, Inc. business.
-// Permission to use, copy, modify, and distribute this
-// software is freely granted, provided that this notice
-// is preserved.
-// ====================================================
-//
-// __ieee754_lgamma_r(x, signgamp)
-// Reentrant version of the logarithm of the Gamma function
-// with user provided pointer for the sign of Gamma(x).
-//
-// Method:
-//   1. Argument Reduction for 0 < x <= 8
-//      Since gamma(1+s)=s*gamma(s), for x in [0,8], we may
-//      reduce x to a number in [1.5,2.5] by
-//              lgamma(1+s) = log(s) + lgamma(s)
-//      for example,
-//              lgamma(7.3) = log(6.3) + lgamma(6.3)
-//                          = log(6.3*5.3) + lgamma(5.3)
-//                          = log(6.3*5.3*4.3*3.3*2.3) + lgamma(2.3)
-//   2. Polynomial approximation of lgamma around its
-//      minimum (ymin=1.461632144968362245) to maintain monotonicity.
-//      On [ymin-0.23, ymin+0.27] (i.e., [1.23164,1.73163]), use
-//              Let z = x-ymin;
-//              lgamma(x) = -1.214862905358496078218 + z**2*poly(z)
-//              poly(z) is a 14 degree polynomial.
-//   2. Rational approximation in the primary interval [2,3]
-//      We use the following approximation:
-//              s = x-2.0;
-//              lgamma(x) = 0.5*s + s*P(s)/Q(s)
-//      with accuracy
-//              |P/Q - (lgamma(x)-0.5s)| < 2**-61.71
-//      Our algorithms are based on the following observation
-//
-//                             zeta(2)-1    2    zeta(3)-1    3
-// lgamma(2+s) = s*(1-Euler) + --------- * s  -  --------- * s  + ...
-//                                 2                 3
-//
-//      where Euler = 0.5772156649... is the Euler constant, which
-//      is very close to 0.5.
-//
-//   3. For x>=8, we have
-//      lgamma(x)~(x-0.5)log(x)-x+0.5*log(2pi)+1/(12x)-1/(360x**3)+....
-//      (better formula:
-//         lgamma(x)~(x-0.5)*(log(x)-1)-.5*(log(2pi)-1) + ...)
-//      Let z = 1/x, then we approximation
-//              f(z) = lgamma(x) - (x-0.5)(log(x)-1)
-//      by
-//                                  3       5             11
-//              w = w0 + w1*z + w2*z  + w3*z  + ... + w6*z
-//      where
-//              |w - f(z)| < 2**-58.74
-//
-//   4. For negative x, since (G is gamma function)
-//              -x*G(-x)*G(x) = pi/sin(pi*x),
-//      we have
-//              G(x) = pi/(sin(pi*x)*(-x)*G(-x))
-//      since G(-x) is positive, sign(G(x)) = sign(sin(pi*x)) for x<0
-//      Hence, for x<0, signgam = sign(sin(pi*x)) and
-//              lgamma(x) = log(|Gamma(x)|)
-//                        = log(pi/(|x*sin(pi*x)|)) - lgamma(-x);
-//      Note: one should avoid computing pi*(-x) directly in the
-//            computation of sin(pi*(-x)).
-//
-//   5. Special Cases
-//              lgamma(2+s) ~ s*(1-Euler) for tiny s
-//              lgamma(1)=lgamma(2)=0
-//              lgamma(x) ~ -log(x) for tiny x
-//              lgamma(0) = lgamma(inf) = inf
-//              lgamma(-integer) = +-inf
-//
-//
-
-var _lgamA = [...]float64{
-	7.72156649015328655494e-02, // 0x3FB3C467E37DB0C8
-	3.22467033424113591611e-01, // 0x3FD4A34CC4A60FAD
-	6.73523010531292681824e-02, // 0x3FB13E001A5562A7
-	2.05808084325167332806e-02, // 0x3F951322AC92547B
-	7.38555086081402883957e-03, // 0x3F7E404FB68FEFE8
-	2.89051383673415629091e-03, // 0x3F67ADD8CCB7926B
-	1.19270763183362067845e-03, // 0x3F538A94116F3F5D
-	5.10069792153511336608e-04, // 0x3F40B6C689B99C00
-	2.20862790713908385557e-04, // 0x3F2CF2ECED10E54D
-	1.08011567247583939954e-04, // 0x3F1C5088987DFB07
-	2.52144565451257326939e-05, // 0x3EFA7074428CFA52
-	4.48640949618915160150e-05, // 0x3F07858E90A45837
-}
-var _lgamR = [...]float64{
-	1.0,                        // placeholder
-	1.39200533467621045958e+00, // 0x3FF645A762C4AB74
-	7.21935547567138069525e-01, // 0x3FE71A1893D3DCDC
-	1.71933865632803078993e-01, // 0x3FC601EDCCFBDF27
-	1.86459191715652901344e-02, // 0x3F9317EA742ED475
-	7.77942496381893596434e-04, // 0x3F497DDACA41A95B
-	7.32668430744625636189e-06, // 0x3EDEBAF7A5B38140
-}
-var _lgamS = [...]float64{
-	-7.72156649015328655494e-02, // 0xBFB3C467E37DB0C8
-	2.14982415960608852501e-01,  // 0x3FCB848B36E20878
-	3.25778796408930981787e-01,  // 0x3FD4D98F4F139F59
-	1.46350472652464452805e-01,  // 0x3FC2BB9CBEE5F2F7
-	2.66422703033638609560e-02,  // 0x3F9B481C7E939961
-	1.84028451407337715652e-03,  // 0x3F5E26B67368F239
-	3.19475326584100867617e-05,  // 0x3F00BFECDD17E945
-}
-var _lgamT = [...]float64{
-	4.83836122723810047042e-01,  // 0x3FDEF72BC8EE38A2
-	-1.47587722994593911752e-01, // 0xBFC2E4278DC6C509
-	6.46249402391333854778e-02,  // 0x3FB08B4294D5419B
-	-3.27885410759859649565e-02, // 0xBFA0C9A8DF35B713
-	1.79706750811820387126e-02,  // 0x3F9266E7970AF9EC
-	-1.03142241298341437450e-02, // 0xBF851F9FBA91EC6A
-	6.10053870246291332635e-03,  // 0x3F78FCE0E370E344
-	-3.68452016781138256760e-03, // 0xBF6E2EFFB3E914D7
-	2.25964780900612472250e-03,  // 0x3F6282D32E15C915
-	-1.40346469989232843813e-03, // 0xBF56FE8EBF2D1AF1
-	8.81081882437654011382e-04,  // 0x3F4CDF0CEF61A8E9
-	-5.38595305356740546715e-04, // 0xBF41A6109C73E0EC
-	3.15632070903625950361e-04,  // 0x3F34AF6D6C0EBBF7
-	-3.12754168375120860518e-04, // 0xBF347F24ECC38C38
-	3.35529192635519073543e-04,  // 0x3F35FD3EE8C2D3F4
-}
-var _lgamU = [...]float64{
-	-7.72156649015328655494e-02, // 0xBFB3C467E37DB0C8
-	6.32827064025093366517e-01,  // 0x3FE4401E8B005DFF
-	1.45492250137234768737e+00,  // 0x3FF7475CD119BD6F
-	9.77717527963372745603e-01,  // 0x3FEF497644EA8450
-	2.28963728064692451092e-01,  // 0x3FCD4EAEF6010924
-	1.33810918536787660377e-02,  // 0x3F8B678BBF2BAB09
-}
-var _lgamV = [...]float64{
-	1.0,
-	2.45597793713041134822e+00, // 0x4003A5D7C2BD619C
-	2.12848976379893395361e+00, // 0x40010725A42B18F5
-	7.69285150456672783825e-01, // 0x3FE89DFBE45050AF
-	1.04222645593369134254e-01, // 0x3FBAAE55D6537C88
-	3.21709242282423911810e-03, // 0x3F6A5ABB57D0CF61
-}
-var _lgamW = [...]float64{
-	4.18938533204672725052e-01,  // 0x3FDACFE390C97D69
-	8.33333333333329678849e-02,  // 0x3FB555555555553B
-	-2.77777777728775536470e-03, // 0xBF66C16C16B02E5C
-	7.93650558643019558500e-04,  // 0x3F4A019F98CF38B6
-	-5.95187557450339963135e-04, // 0xBF4380CB8C0FE741
-	8.36339918996282139126e-04,  // 0x3F4B67BA4CDAD5D1
-	-1.63092934096575273989e-03, // 0xBF5AB89D0B9E43E4
-}
-
-// Lgamma returns the natural logarithm and sign (-1 or +1) of Gamma(x).
-//
-// Special cases are:
-//	Lgamma(+Inf) = +Inf
-//	Lgamma(0) = +Inf
-//	Lgamma(-integer) = +Inf
-//	Lgamma(-Inf) = -Inf
-//	Lgamma(NaN) = NaN
-func Lgamma(x float64) (lgamma float64, sign int) {
-	const (
-		Ymin  = 1.461632144968362245
-		Two52 = 1 << 52                     // 0x4330000000000000 ~4.5036e+15
-		Two53 = 1 << 53                     // 0x4340000000000000 ~9.0072e+15
-		Two58 = 1 << 58                     // 0x4390000000000000 ~2.8823e+17
-		Tiny  = 1.0 / (1 << 70)             // 0x3b90000000000000 ~8.47033e-22
-		Tc    = 1.46163214496836224576e+00  // 0x3FF762D86356BE3F
-		Tf    = -1.21486290535849611461e-01 // 0xBFBF19B9BCC38A42
-		// Tt = -(tail of Tf)
-		Tt = -3.63867699703950536541e-18 // 0xBC50C7CAA48A971F
-	)
-	// special cases
-	sign = 1
-	switch {
-	case IsNaN(x):
-		lgamma = x
-		return
-	case IsInf(x, 0):
-		lgamma = x
-		return
-	case x == 0:
-		lgamma = Inf(1)
-		return
-	}
-
-	neg := false
-	if x < 0 {
-		x = -x
-		neg = true
-	}
-
-	if x < Tiny { // if |x| < 2**-70, return -log(|x|)
-		if neg {
-			sign = -1
-		}
-		lgamma = -Log(x)
-		return
-	}
-	var nadj float64
-	if neg {
-		if x >= Two52 { // |x| >= 2**52, must be -integer
-			lgamma = Inf(1)
-			return
-		}
-		t := sinPi(x)
-		if t == 0 {
-			lgamma = Inf(1) // -integer
-			return
-		}
-		nadj = Log(Pi / Abs(t*x))
-		if t < 0 {
-			sign = -1
-		}
-	}
-
-	switch {
-	case x == 1 || x == 2: // purge off 1 and 2
-		lgamma = 0
-		return
-	case x < 2: // use lgamma(x) = lgamma(x+1) - log(x)
-		var y float64
-		var i int
-		if x <= 0.9 {
-			lgamma = -Log(x)
-			switch {
-			case x >= (Ymin - 1 + 0.27): // 0.7316 <= x <=  0.9
-				y = 1 - x
-				i = 0
-			case x >= (Ymin - 1 - 0.27): // 0.2316 <= x < 0.7316
-				y = x - (Tc - 1)
-				i = 1
-			default: // 0 < x < 0.2316
-				y = x
-				i = 2
-			}
-		} else {
-			lgamma = 0
-			switch {
-			case x >= (Ymin + 0.27): // 1.7316 <= x < 2
-				y = 2 - x
-				i = 0
-			case x >= (Ymin - 0.27): // 1.2316 <= x < 1.7316
-				y = x - Tc
-				i = 1
-			default: // 0.9 < x < 1.2316
-				y = x - 1
-				i = 2
-			}
-		}
-		switch i {
-		case 0:
-			z := y * y
-			p1 := _lgamA[0] + z*(_lgamA[2]+z*(_lgamA[4]+z*(_lgamA[6]+z*(_lgamA[8]+z*_lgamA[10]))))
-			p2 := z * (_lgamA[1] + z*(+_lgamA[3]+z*(_lgamA[5]+z*(_lgamA[7]+z*(_lgamA[9]+z*_lgamA[11])))))
-			p := y*p1 + p2
-			lgamma += (p - 0.5*y)
-		case 1:
-			z := y * y
-			w := z * y
-			p1 := _lgamT[0] + w*(_lgamT[3]+w*(_lgamT[6]+w*(_lgamT[9]+w*_lgamT[12]))) // parallel comp
-			p2 := _lgamT[1] + w*(_lgamT[4]+w*(_lgamT[7]+w*(_lgamT[10]+w*_lgamT[13])))
-			p3 := _lgamT[2] + w*(_lgamT[5]+w*(_lgamT[8]+w*(_lgamT[11]+w*_lgamT[14])))
-			p := z*p1 - (Tt - w*(p2+y*p3))
-			lgamma += (Tf + p)
-		case 2:
-			p1 := y * (_lgamU[0] + y*(_lgamU[1]+y*(_lgamU[2]+y*(_lgamU[3]+y*(_lgamU[4]+y*_lgamU[5])))))
-			p2 := 1 + y*(_lgamV[1]+y*(_lgamV[2]+y*(_lgamV[3]+y*(_lgamV[4]+y*_lgamV[5]))))
-			lgamma += (-0.5*y + p1/p2)
-		}
-	case x < 8: // 2 <= x < 8
-		i := int(x)
-		y := x - float64(i)
-		p := y * (_lgamS[0] + y*(_lgamS[1]+y*(_lgamS[2]+y*(_lgamS[3]+y*(_lgamS[4]+y*(_lgamS[5]+y*_lgamS[6]))))))
-		q := 1 + y*(_lgamR[1]+y*(_lgamR[2]+y*(_lgamR[3]+y*(_lgamR[4]+y*(_lgamR[5]+y*_lgamR[6])))))
-		lgamma = 0.5*y + p/q
-		z := 1.0 // Lgamma(1+s) = Log(s) + Lgamma(s)
-		switch i {
-		case 7:
-			z *= (y + 6)
-			fallthrough
-		case 6:
-			z *= (y + 5)
-			fallthrough
-		case 5:
-			z *= (y + 4)
-			fallthrough
-		case 4:
-			z *= (y + 3)
-			fallthrough
-		case 3:
-			z *= (y + 2)
-			lgamma += Log(z)
-		}
-	case x < Two58: // 8 <= x < 2**58
-		t := Log(x)
-		z := 1 / x
-		y := z * z
-		w := _lgamW[0] + z*(_lgamW[1]+y*(_lgamW[2]+y*(_lgamW[3]+y*(_lgamW[4]+y*(_lgamW[5]+y*_lgamW[6])))))
-		lgamma = (x-0.5)*(t-1) + w
-	default: // 2**58 <= x <= Inf
-		lgamma = x * (Log(x) - 1)
-	}
-	if neg {
-		lgamma = nadj - lgamma
-	}
-	return
-}
-
-// sinPi(x) is a helper function for negative x
-func sinPi(x float64) float64 {
-	const (
-		Two52 = 1 << 52 // 0x4330000000000000 ~4.5036e+15
-		Two53 = 1 << 53 // 0x4340000000000000 ~9.0072e+15
-	)
-	if x < 0.25 {
-		return -Sin(Pi * x)
-	}
-
-	// argument reduction
-	z := Floor(x)
-	var n int
-	if z != x { // inexact
-		x = Mod(x, 2)
-		n = int(x * 4)
-	} else {
-		if x >= Two53 { // x must be even
-			x = 0
-			n = 0
-		} else {
-			if x < Two52 {
-				z = x + Two52 // exact
-			}
-			n = int(1 & Float64bits(z))
-			x = float64(n)
-			n <<= 2
-		}
-	}
-	switch n {
-	case 0:
-		x = Sin(Pi * x)
-	case 1, 2:
-		x = Cos(Pi * (0.5 - x))
-	case 3, 4:
-		x = Sin(Pi * (1 - x))
-	case 5, 6:
-		x = -Cos(Pi * (x - 1.5))
-	default:
-		x = Sin(Pi * (x - 2))
-	}
-	return -x
-}
diff --git a/contrib/go/_std_1.18/src/math/log.go b/contrib/go/_std_1.18/src/math/log.go
deleted file mode 100644
index 1b3e306adf..0000000000
--- a/contrib/go/_std_1.18/src/math/log.go
+++ /dev/null
@@ -1,128 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-/*
-	Floating-point logarithm.
-*/
-
-// The original C code, the long comment, and the constants
-// below are from FreeBSD's /usr/src/lib/msun/src/e_log.c
-// and came with this notice. The go code is a simpler
-// version of the original C.
-//
-// ====================================================
-// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
-//
-// Developed at SunPro, a Sun Microsystems, Inc. business.
-// Permission to use, copy, modify, and distribute this
-// software is freely granted, provided that this notice
-// is preserved.
-// ====================================================
-//
-// __ieee754_log(x)
-// Return the logarithm of x
-//
-// Method :
-//   1. Argument Reduction: find k and f such that
-//			x = 2**k * (1+f),
-//	   where  sqrt(2)/2 < 1+f < sqrt(2) .
-//
-//   2. Approximation of log(1+f).
-//	Let s = f/(2+f) ; based on log(1+f) = log(1+s) - log(1-s)
-//		 = 2s + 2/3 s**3 + 2/5 s**5 + .....,
-//	     	 = 2s + s*R
-//      We use a special Reme algorithm on [0,0.1716] to generate
-//	a polynomial of degree 14 to approximate R.  The maximum error
-//	of this polynomial approximation is bounded by 2**-58.45. In
-//	other words,
-//		        2      4      6      8      10      12      14
-//	    R(z) ~ L1*s +L2*s +L3*s +L4*s +L5*s  +L6*s  +L7*s
-//	(the values of L1 to L7 are listed in the program) and
-//	    |      2          14          |     -58.45
-//	    | L1*s +...+L7*s    -  R(z) | <= 2
-//	    |                             |
-//	Note that 2s = f - s*f = f - hfsq + s*hfsq, where hfsq = f*f/2.
-//	In order to guarantee error in log below 1ulp, we compute log by
-//		log(1+f) = f - s*(f - R)		(if f is not too large)
-//		log(1+f) = f - (hfsq - s*(hfsq+R)).	(better accuracy)
-//
-//	3. Finally,  log(x) = k*Ln2 + log(1+f).
-//			    = k*Ln2_hi+(f-(hfsq-(s*(hfsq+R)+k*Ln2_lo)))
-//	   Here Ln2 is split into two floating point number:
-//			Ln2_hi + Ln2_lo,
-//	   where n*Ln2_hi is always exact for |n| < 2000.
-//
-// Special cases:
-//	log(x) is NaN with signal if x < 0 (including -INF) ;
-//	log(+INF) is +INF; log(0) is -INF with signal;
-//	log(NaN) is that NaN with no signal.
-//
-// Accuracy:
-//	according to an error analysis, the error is always less than
-//	1 ulp (unit in the last place).
-//
-// Constants:
-// The hexadecimal values are the intended ones for the following
-// constants. The decimal values may be used, provided that the
-// compiler will convert from decimal to binary accurately enough
-// to produce the hexadecimal values shown.
-
-// Log returns the natural logarithm of x.
-//
-// Special cases are:
-//	Log(+Inf) = +Inf
-//	Log(0) = -Inf
-//	Log(x < 0) = NaN
-//	Log(NaN) = NaN
-func Log(x float64) float64 {
-	if haveArchLog {
-		return archLog(x)
-	}
-	return log(x)
-}
-
-func log(x float64) float64 {
-	const (
-		Ln2Hi = 6.93147180369123816490e-01 /* 3fe62e42 fee00000 */
-		Ln2Lo = 1.90821492927058770002e-10 /* 3dea39ef 35793c76 */
-		L1    = 6.666666666666735130e-01   /* 3FE55555 55555593 */
-		L2    = 3.999999999940941908e-01   /* 3FD99999 9997FA04 */
-		L3    = 2.857142874366239149e-01   /* 3FD24924 94229359 */
-		L4    = 2.222219843214978396e-01   /* 3FCC71C5 1D8E78AF */
-		L5    = 1.818357216161805012e-01   /* 3FC74664 96CB03DE */
-		L6    = 1.531383769920937332e-01   /* 3FC39A09 D078C69F */
-		L7    = 1.479819860511658591e-01   /* 3FC2F112 DF3E5244 */
-	)
-
-	// special cases
-	switch {
-	case IsNaN(x) || IsInf(x, 1):
-		return x
-	case x < 0:
-		return NaN()
-	case x == 0:
-		return Inf(-1)
-	}
-
-	// reduce
-	f1, ki := Frexp(x)
-	if f1 < Sqrt2/2 {
-		f1 *= 2
-		ki--
-	}
-	f := f1 - 1
-	k := float64(ki)
-
-	// compute
-	s := f / (2 + f)
-	s2 := s * s
-	s4 := s2 * s2
-	t1 := s2 * (L1 + s4*(L3+s4*(L5+s4*L7)))
-	t2 := s4 * (L2 + s4*(L4+s4*L6))
-	R := t1 + t2
-	hfsq := 0.5 * f * f
-	return k*Ln2Hi - ((hfsq - (s*(hfsq+R) + k*Ln2Lo)) - f)
-}
diff --git a/contrib/go/_std_1.18/src/math/log1p.go b/contrib/go/_std_1.18/src/math/log1p.go
deleted file mode 100644
index c117f7245d..0000000000
--- a/contrib/go/_std_1.18/src/math/log1p.go
+++ /dev/null
@@ -1,202 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-// The original C code, the long comment, and the constants
-// below are from FreeBSD's /usr/src/lib/msun/src/s_log1p.c
-// and came with this notice. The go code is a simplified
-// version of the original C.
-//
-// ====================================================
-// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
-//
-// Developed at SunPro, a Sun Microsystems, Inc. business.
-// Permission to use, copy, modify, and distribute this
-// software is freely granted, provided that this notice
-// is preserved.
-// ====================================================
-//
-//
-// double log1p(double x)
-//
-// Method :
-//   1. Argument Reduction: find k and f such that
-//                      1+x = 2**k * (1+f),
-//         where  sqrt(2)/2 < 1+f < sqrt(2) .
-//
-//      Note. If k=0, then f=x is exact. However, if k!=0, then f
-//      may not be representable exactly. In that case, a correction
-//      term is need. Let u=1+x rounded. Let c = (1+x)-u, then
-//      log(1+x) - log(u) ~ c/u. Thus, we proceed to compute log(u),
-//      and add back the correction term c/u.
-//      (Note: when x > 2**53, one can simply return log(x))
-//
-//   2. Approximation of log1p(f).
-//      Let s = f/(2+f) ; based on log(1+f) = log(1+s) - log(1-s)
-//               = 2s + 2/3 s**3 + 2/5 s**5 + .....,
-//               = 2s + s*R
-//      We use a special Reme algorithm on [0,0.1716] to generate
-//      a polynomial of degree 14 to approximate R The maximum error
-//      of this polynomial approximation is bounded by 2**-58.45. In
-//      other words,
-//                      2      4      6      8      10      12      14
-//          R(z) ~ Lp1*s +Lp2*s +Lp3*s +Lp4*s +Lp5*s  +Lp6*s  +Lp7*s
-//      (the values of Lp1 to Lp7 are listed in the program)
-//      and
-//          |      2          14          |     -58.45
-//          | Lp1*s +...+Lp7*s    -  R(z) | <= 2
-//          |                             |
-//      Note that 2s = f - s*f = f - hfsq + s*hfsq, where hfsq = f*f/2.
-//      In order to guarantee error in log below 1ulp, we compute log
-//      by
-//              log1p(f) = f - (hfsq - s*(hfsq+R)).
-//
-//   3. Finally, log1p(x) = k*ln2 + log1p(f).
-//                        = k*ln2_hi+(f-(hfsq-(s*(hfsq+R)+k*ln2_lo)))
-//      Here ln2 is split into two floating point number:
-//                   ln2_hi + ln2_lo,
-//      where n*ln2_hi is always exact for |n| < 2000.
-//
-// Special cases:
-//      log1p(x) is NaN with signal if x < -1 (including -INF) ;
-//      log1p(+INF) is +INF; log1p(-1) is -INF with signal;
-//      log1p(NaN) is that NaN with no signal.
-//
-// Accuracy:
-//      according to an error analysis, the error is always less than
-//      1 ulp (unit in the last place).
-//
-// Constants:
-// The hexadecimal values are the intended ones for the following
-// constants. The decimal values may be used, provided that the
-// compiler will convert from decimal to binary accurately enough
-// to produce the hexadecimal values shown.
-//
-// Note: Assuming log() return accurate answer, the following
-//       algorithm can be used to compute log1p(x) to within a few ULP:
-//
-//              u = 1+x;
-//              if(u==1.0) return x ; else
-//                         return log(u)*(x/(u-1.0));
-//
-//       See HP-15C Advanced Functions Handbook, p.193.
-
-// Log1p returns the natural logarithm of 1 plus its argument x.
-// It is more accurate than Log(1 + x) when x is near zero.
-//
-// Special cases are:
-//	Log1p(+Inf) = +Inf
-//	Log1p(±0) = ±0
-//	Log1p(-1) = -Inf
-//	Log1p(x < -1) = NaN
-//	Log1p(NaN) = NaN
-func Log1p(x float64) float64 {
-	if haveArchLog1p {
-		return archLog1p(x)
-	}
-	return log1p(x)
-}
-
-func log1p(x float64) float64 {
-	const (
-		Sqrt2M1     = 4.142135623730950488017e-01  // Sqrt(2)-1 = 0x3fda827999fcef34
-		Sqrt2HalfM1 = -2.928932188134524755992e-01 // Sqrt(2)/2-1 = 0xbfd2bec333018866
-		Small       = 1.0 / (1 << 29)              // 2**-29 = 0x3e20000000000000
-		Tiny        = 1.0 / (1 << 54)              // 2**-54
-		Two53       = 1 << 53                      // 2**53
-		Ln2Hi       = 6.93147180369123816490e-01   // 3fe62e42fee00000
-		Ln2Lo       = 1.90821492927058770002e-10   // 3dea39ef35793c76
-		Lp1         = 6.666666666666735130e-01     // 3FE5555555555593
-		Lp2         = 3.999999999940941908e-01     // 3FD999999997FA04
-		Lp3         = 2.857142874366239149e-01     // 3FD2492494229359
-		Lp4         = 2.222219843214978396e-01     // 3FCC71C51D8E78AF
-		Lp5         = 1.818357216161805012e-01     // 3FC7466496CB03DE
-		Lp6         = 1.531383769920937332e-01     // 3FC39A09D078C69F
-		Lp7         = 1.479819860511658591e-01     // 3FC2F112DF3E5244
-	)
-
-	// special cases
-	switch {
-	case x < -1 || IsNaN(x): // includes -Inf
-		return NaN()
-	case x == -1:
-		return Inf(-1)
-	case IsInf(x, 1):
-		return Inf(1)
-	}
-
-	absx := Abs(x)
-
-	var f float64
-	var iu uint64
-	k := 1
-	if absx < Sqrt2M1 { //  |x| < Sqrt(2)-1
-		if absx < Small { // |x| < 2**-29
-			if absx < Tiny { // |x| < 2**-54
-				return x
-			}
-			return x - x*x*0.5
-		}
-		if x > Sqrt2HalfM1 { // Sqrt(2)/2-1 < x
-			// (Sqrt(2)/2-1) < x < (Sqrt(2)-1)
-			k = 0
-			f = x
-			iu = 1
-		}
-	}
-	var c float64
-	if k != 0 {
-		var u float64
-		if absx < Two53 { // 1<<53
-			u = 1.0 + x
-			iu = Float64bits(u)
-			k = int((iu >> 52) - 1023)
-			// correction term
-			if k > 0 {
-				c = 1.0 - (u - x)
-			} else {
-				c = x - (u - 1.0)
-			}
-			c /= u
-		} else {
-			u = x
-			iu = Float64bits(u)
-			k = int((iu >> 52) - 1023)
-			c = 0
-		}
-		iu &= 0x000fffffffffffff
-		if iu < 0x0006a09e667f3bcd { // mantissa of Sqrt(2)
-			u = Float64frombits(iu | 0x3ff0000000000000) // normalize u
-		} else {
-			k++
-			u = Float64frombits(iu | 0x3fe0000000000000) // normalize u/2
-			iu = (0x0010000000000000 - iu) >> 2
-		}
-		f = u - 1.0 // Sqrt(2)/2 < u < Sqrt(2)
-	}
-	hfsq := 0.5 * f * f
-	var s, R, z float64
-	if iu == 0 { // |f| < 2**-20
-		if f == 0 {
-			if k == 0 {
-				return 0
-			}
-			c += float64(k) * Ln2Lo
-			return float64(k)*Ln2Hi + c
-		}
-		R = hfsq * (1.0 - 0.66666666666666666*f) // avoid division
-		if k == 0 {
-			return f - R
-		}
-		return float64(k)*Ln2Hi - ((R - (float64(k)*Ln2Lo + c)) - f)
-	}
-	s = f / (2.0 + f)
-	z = s * s
-	R = z * (Lp1 + z*(Lp2+z*(Lp3+z*(Lp4+z*(Lp5+z*(Lp6+z*Lp7))))))
-	if k == 0 {
-		return f - (hfsq - s*(hfsq+R))
-	}
-	return float64(k)*Ln2Hi - ((hfsq - (s*(hfsq+R) + (float64(k)*Ln2Lo + c))) - f)
-}
diff --git a/contrib/go/_std_1.18/src/math/logb.go b/contrib/go/_std_1.18/src/math/logb.go
deleted file mode 100644
index f2769d4fd7..0000000000
--- a/contrib/go/_std_1.18/src/math/logb.go
+++ /dev/null
@@ -1,50 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-// Logb returns the binary exponent of x.
-//
-// Special cases are:
-//	Logb(±Inf) = +Inf
-//	Logb(0) = -Inf
-//	Logb(NaN) = NaN
-func Logb(x float64) float64 {
-	// special cases
-	switch {
-	case x == 0:
-		return Inf(-1)
-	case IsInf(x, 0):
-		return Inf(1)
-	case IsNaN(x):
-		return x
-	}
-	return float64(ilogb(x))
-}
-
-// Ilogb returns the binary exponent of x as an integer.
-//
-// Special cases are:
-//	Ilogb(±Inf) = MaxInt32
-//	Ilogb(0) = MinInt32
-//	Ilogb(NaN) = MaxInt32
-func Ilogb(x float64) int {
-	// special cases
-	switch {
-	case x == 0:
-		return MinInt32
-	case IsNaN(x):
-		return MaxInt32
-	case IsInf(x, 0):
-		return MaxInt32
-	}
-	return ilogb(x)
-}
-
-// logb returns the binary exponent of x. It assumes x is finite and
-// non-zero.
-func ilogb(x float64) int {
-	x, exp := normalize(x)
-	return int((Float64bits(x)>>shift)&mask) - bias + exp
-}
diff --git a/contrib/go/_std_1.18/src/math/mod.go b/contrib/go/_std_1.18/src/math/mod.go
deleted file mode 100644
index 6bc5f28832..0000000000
--- a/contrib/go/_std_1.18/src/math/mod.go
+++ /dev/null
@@ -1,51 +0,0 @@
-// Copyright 2009-2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-/*
-	Floating-point mod function.
-*/
-
-// Mod returns the floating-point remainder of x/y.
-// The magnitude of the result is less than y and its
-// sign agrees with that of x.
-//
-// Special cases are:
-//	Mod(±Inf, y) = NaN
-//	Mod(NaN, y) = NaN
-//	Mod(x, 0) = NaN
-//	Mod(x, ±Inf) = x
-//	Mod(x, NaN) = NaN
-func Mod(x, y float64) float64 {
-	if haveArchMod {
-		return archMod(x, y)
-	}
-	return mod(x, y)
-}
-
-func mod(x, y float64) float64 {
-	if y == 0 || IsInf(x, 0) || IsNaN(x) || IsNaN(y) {
-		return NaN()
-	}
-	y = Abs(y)
-
-	yfr, yexp := Frexp(y)
-	r := x
-	if x < 0 {
-		r = -x
-	}
-
-	for r >= y {
-		rfr, rexp := Frexp(r)
-		if rfr < yfr {
-			rexp = rexp - 1
-		}
-		r = r - Ldexp(y, rexp-yexp)
-	}
-	if x < 0 {
-		r = -r
-	}
-	return r
-}
diff --git a/contrib/go/_std_1.18/src/math/modf.go b/contrib/go/_std_1.18/src/math/modf.go
deleted file mode 100644
index bf08dc6556..0000000000
--- a/contrib/go/_std_1.18/src/math/modf.go
+++ /dev/null
@@ -1,42 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-// Modf returns integer and fractional floating-point numbers
-// that sum to f. Both values have the same sign as f.
-//
-// Special cases are:
-//	Modf(±Inf) = ±Inf, NaN
-//	Modf(NaN) = NaN, NaN
-func Modf(f float64) (int float64, frac float64) {
-	if haveArchModf {
-		return archModf(f)
-	}
-	return modf(f)
-}
-
-func modf(f float64) (int float64, frac float64) {
-	if f < 1 {
-		switch {
-		case f < 0:
-			int, frac = Modf(-f)
-			return -int, -frac
-		case f == 0:
-			return f, f // Return -0, -0 when f == -0
-		}
-		return 0, f
-	}
-
-	x := Float64bits(f)
-	e := uint(x>>shift)&mask - bias
-
-	// Keep the top 12+e bits, the integer part; clear the rest.
-	if e < 64-12 {
-		x &^= 1<<(64-12-e) - 1
-	}
-	int = Float64frombits(x)
-	frac = f - int
-	return
-}
diff --git a/contrib/go/_std_1.18/src/math/nextafter.go b/contrib/go/_std_1.18/src/math/nextafter.go
deleted file mode 100644
index 9088e4d248..0000000000
--- a/contrib/go/_std_1.18/src/math/nextafter.go
+++ /dev/null
@@ -1,49 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-// Nextafter32 returns the next representable float32 value after x towards y.
-//
-// Special cases are:
-//	Nextafter32(x, x)   = x
-//	Nextafter32(NaN, y) = NaN
-//	Nextafter32(x, NaN) = NaN
-func Nextafter32(x, y float32) (r float32) {
-	switch {
-	case IsNaN(float64(x)) || IsNaN(float64(y)): // special case
-		r = float32(NaN())
-	case x == y:
-		r = x
-	case x == 0:
-		r = float32(Copysign(float64(Float32frombits(1)), float64(y)))
-	case (y > x) == (x > 0):
-		r = Float32frombits(Float32bits(x) + 1)
-	default:
-		r = Float32frombits(Float32bits(x) - 1)
-	}
-	return
-}
-
-// Nextafter returns the next representable float64 value after x towards y.
-//
-// Special cases are:
-//	Nextafter(x, x)   = x
-//	Nextafter(NaN, y) = NaN
-//	Nextafter(x, NaN) = NaN
-func Nextafter(x, y float64) (r float64) {
-	switch {
-	case IsNaN(x) || IsNaN(y): // special case
-		r = NaN()
-	case x == y:
-		r = x
-	case x == 0:
-		r = Copysign(Float64frombits(1), y)
-	case (y > x) == (x > 0):
-		r = Float64frombits(Float64bits(x) + 1)
-	default:
-		r = Float64frombits(Float64bits(x) - 1)
-	}
-	return
-}
diff --git a/contrib/go/_std_1.18/src/math/pow.go b/contrib/go/_std_1.18/src/math/pow.go
deleted file mode 100644
index e45a044ae1..0000000000
--- a/contrib/go/_std_1.18/src/math/pow.go
+++ /dev/null
@@ -1,156 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-func isOddInt(x float64) bool {
-	xi, xf := Modf(x)
-	return xf == 0 && int64(xi)&1 == 1
-}
-
-// Special cases taken from FreeBSD's /usr/src/lib/msun/src/e_pow.c
-// updated by IEEE Std. 754-2008 "Section 9.2.1 Special values".
-
-// Pow returns x**y, the base-x exponential of y.
-//
-// Special cases are (in order):
-//	Pow(x, ±0) = 1 for any x
-//	Pow(1, y) = 1 for any y
-//	Pow(x, 1) = x for any x
-//	Pow(NaN, y) = NaN
-//	Pow(x, NaN) = NaN
-//	Pow(±0, y) = ±Inf for y an odd integer < 0
-//	Pow(±0, -Inf) = +Inf
-//	Pow(±0, +Inf) = +0
-//	Pow(±0, y) = +Inf for finite y < 0 and not an odd integer
-//	Pow(±0, y) = ±0 for y an odd integer > 0
-//	Pow(±0, y) = +0 for finite y > 0 and not an odd integer
-//	Pow(-1, ±Inf) = 1
-//	Pow(x, +Inf) = +Inf for |x| > 1
-//	Pow(x, -Inf) = +0 for |x| > 1
-//	Pow(x, +Inf) = +0 for |x| < 1
-//	Pow(x, -Inf) = +Inf for |x| < 1
-//	Pow(+Inf, y) = +Inf for y > 0
-//	Pow(+Inf, y) = +0 for y < 0
-//	Pow(-Inf, y) = Pow(-0, -y)
-//	Pow(x, y) = NaN for finite x < 0 and finite non-integer y
-func Pow(x, y float64) float64 {
-	if haveArchPow {
-		return archPow(x, y)
-	}
-	return pow(x, y)
-}
-
-func pow(x, y float64) float64 {
-	switch {
-	case y == 0 || x == 1:
-		return 1
-	case y == 1:
-		return x
-	case IsNaN(x) || IsNaN(y):
-		return NaN()
-	case x == 0:
-		switch {
-		case y < 0:
-			if isOddInt(y) {
-				return Copysign(Inf(1), x)
-			}
-			return Inf(1)
-		case y > 0:
-			if isOddInt(y) {
-				return x
-			}
-			return 0
-		}
-	case IsInf(y, 0):
-		switch {
-		case x == -1:
-			return 1
-		case (Abs(x) < 1) == IsInf(y, 1):
-			return 0
-		default:
-			return Inf(1)
-		}
-	case IsInf(x, 0):
-		if IsInf(x, -1) {
-			return Pow(1/x, -y) // Pow(-0, -y)
-		}
-		switch {
-		case y < 0:
-			return 0
-		case y > 0:
-			return Inf(1)
-		}
-	case y == 0.5:
-		return Sqrt(x)
-	case y == -0.5:
-		return 1 / Sqrt(x)
-	}
-
-	yi, yf := Modf(Abs(y))
-	if yf != 0 && x < 0 {
-		return NaN()
-	}
-	if yi >= 1<<63 {
-		// yi is a large even int that will lead to overflow (or underflow to 0)
-		// for all x except -1 (x == 1 was handled earlier)
-		switch {
-		case x == -1:
-			return 1
-		case (Abs(x) < 1) == (y > 0):
-			return 0
-		default:
-			return Inf(1)
-		}
-	}
-
-	// ans = a1 * 2**ae (= 1 for now).
-	a1 := 1.0
-	ae := 0
-
-	// ans *= x**yf
-	if yf != 0 {
-		if yf > 0.5 {
-			yf--
-			yi++
-		}
-		a1 = Exp(yf * Log(x))
-	}
-
-	// ans *= x**yi
-	// by multiplying in successive squarings
-	// of x according to bits of yi.
-	// accumulate powers of two into exp.
-	x1, xe := Frexp(x)
-	for i := int64(yi); i != 0; i >>= 1 {
-		if xe < -1<<12 || 1<<12 < xe {
-			// catch xe before it overflows the left shift below
-			// Since i !=0 it has at least one bit still set, so ae will accumulate xe
-			// on at least one more iteration, ae += xe is a lower bound on ae
-			// the lower bound on ae exceeds the size of a float64 exp
-			// so the final call to Ldexp will produce under/overflow (0/Inf)
-			ae += xe
-			break
-		}
-		if i&1 == 1 {
-			a1 *= x1
-			ae += xe
-		}
-		x1 *= x1
-		xe <<= 1
-		if x1 < .5 {
-			x1 += x1
-			xe--
-		}
-	}
-
-	// ans = a1*2**ae
-	// if y < 0 { ans = 1 / ans }
-	// but in the opposite order
-	if y < 0 {
-		a1 = 1 / a1
-		ae = -ae
-	}
-	return Ldexp(a1, ae)
-}
diff --git a/contrib/go/_std_1.18/src/math/pow10.go b/contrib/go/_std_1.18/src/math/pow10.go
deleted file mode 100644
index 1234e20885..0000000000
--- a/contrib/go/_std_1.18/src/math/pow10.go
+++ /dev/null
@@ -1,46 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-// pow10tab stores the pre-computed values 10**i for i < 32.
-var pow10tab = [...]float64{
-	1e00, 1e01, 1e02, 1e03, 1e04, 1e05, 1e06, 1e07, 1e08, 1e09,
-	1e10, 1e11, 1e12, 1e13, 1e14, 1e15, 1e16, 1e17, 1e18, 1e19,
-	1e20, 1e21, 1e22, 1e23, 1e24, 1e25, 1e26, 1e27, 1e28, 1e29,
-	1e30, 1e31,
-}
-
-// pow10postab32 stores the pre-computed value for 10**(i*32) at index i.
-var pow10postab32 = [...]float64{
-	1e00, 1e32, 1e64, 1e96, 1e128, 1e160, 1e192, 1e224, 1e256, 1e288,
-}
-
-// pow10negtab32 stores the pre-computed value for 10**(-i*32) at index i.
-var pow10negtab32 = [...]float64{
-	1e-00, 1e-32, 1e-64, 1e-96, 1e-128, 1e-160, 1e-192, 1e-224, 1e-256, 1e-288, 1e-320,
-}
-
-// Pow10 returns 10**n, the base-10 exponential of n.
-//
-// Special cases are:
-//	Pow10(n) =    0 for n < -323
-//	Pow10(n) = +Inf for n > 308
-func Pow10(n int) float64 {
-	if 0 <= n && n <= 308 {
-		return pow10postab32[uint(n)/32] * pow10tab[uint(n)%32]
-	}
-
-	if -323 <= n && n <= 0 {
-		return pow10negtab32[uint(-n)/32] / pow10tab[uint(-n)%32]
-	}
-
-	// n < -323 || 308 < n
-	if n > 0 {
-		return Inf(1)
-	}
-
-	// n < -323
-	return 0
-}
diff --git a/contrib/go/_std_1.18/src/math/rand/exp.go b/contrib/go/_std_1.18/src/math/rand/exp.go
deleted file mode 100644
index 5a8d946c0c..0000000000
--- a/contrib/go/_std_1.18/src/math/rand/exp.go
+++ /dev/null
@@ -1,222 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package rand
-
-import (
-	"math"
-)
-
-/*
- * Exponential distribution
- *
- * See "The Ziggurat Method for Generating Random Variables"
- * (Marsaglia & Tsang, 2000)
- * https://www.jstatsoft.org/v05/i08/paper [pdf]
- */
-
-const (
-	re = 7.69711747013104972
-)
-
-// ExpFloat64 returns an exponentially distributed float64 in the range
-// (0, +math.MaxFloat64] with an exponential distribution whose rate parameter
-// (lambda) is 1 and whose mean is 1/lambda (1).
-// To produce a distribution with a different rate parameter,
-// callers can adjust the output using:
-//
-//  sample = ExpFloat64() / desiredRateParameter
-//
-func (r *Rand) ExpFloat64() float64 {
-	for {
-		j := r.Uint32()
-		i := j & 0xFF
-		x := float64(j) * float64(we[i])
-		if j < ke[i] {
-			return x
-		}
-		if i == 0 {
-			return re - math.Log(r.Float64())
-		}
-		if fe[i]+float32(r.Float64())*(fe[i-1]-fe[i]) < float32(math.Exp(-x)) {
-			return x
-		}
-	}
-}
-
-var ke = [256]uint32{
-	0xe290a139, 0x0, 0x9beadebc, 0xc377ac71, 0xd4ddb990,
-	0xde893fb8, 0xe4a8e87c, 0xe8dff16a, 0xebf2deab, 0xee49a6e8,
-	0xf0204efd, 0xf19bdb8e, 0xf2d458bb, 0xf3da104b, 0xf4b86d78,
-	0xf577ad8a, 0xf61de83d, 0xf6afb784, 0xf730a573, 0xf7a37651,
-	0xf80a5bb6, 0xf867189d, 0xf8bb1b4f, 0xf9079062, 0xf94d70ca,
-	0xf98d8c7d, 0xf9c8928a, 0xf9ff175b, 0xfa319996, 0xfa6085f8,
-	0xfa8c3a62, 0xfab5084e, 0xfadb36c8, 0xfaff0410, 0xfb20a6ea,
-	0xfb404fb4, 0xfb5e2951, 0xfb7a59e9, 0xfb95038c, 0xfbae44ba,
-	0xfbc638d8, 0xfbdcf892, 0xfbf29a30, 0xfc0731df, 0xfc1ad1ed,
-	0xfc2d8b02, 0xfc3f6c4d, 0xfc5083ac, 0xfc60ddd1, 0xfc708662,
-	0xfc7f8810, 0xfc8decb4, 0xfc9bbd62, 0xfca9027c, 0xfcb5c3c3,
-	0xfcc20864, 0xfccdd70a, 0xfcd935e3, 0xfce42ab0, 0xfceebace,
-	0xfcf8eb3b, 0xfd02c0a0, 0xfd0c3f59, 0xfd156b7b, 0xfd1e48d6,
-	0xfd26daff, 0xfd2f2552, 0xfd372af7, 0xfd3eeee5, 0xfd4673e7,
-	0xfd4dbc9e, 0xfd54cb85, 0xfd5ba2f2, 0xfd62451b, 0xfd68b415,
-	0xfd6ef1da, 0xfd750047, 0xfd7ae120, 0xfd809612, 0xfd8620b4,
-	0xfd8b8285, 0xfd90bcf5, 0xfd95d15e, 0xfd9ac10b, 0xfd9f8d36,
-	0xfda43708, 0xfda8bf9e, 0xfdad2806, 0xfdb17141, 0xfdb59c46,
-	0xfdb9a9fd, 0xfdbd9b46, 0xfdc170f6, 0xfdc52bd8, 0xfdc8ccac,
-	0xfdcc542d, 0xfdcfc30b, 0xfdd319ef, 0xfdd6597a, 0xfdd98245,
-	0xfddc94e5, 0xfddf91e6, 0xfde279ce, 0xfde54d1f, 0xfde80c52,
-	0xfdeab7de, 0xfded5034, 0xfdefd5be, 0xfdf248e3, 0xfdf4aa06,
-	0xfdf6f984, 0xfdf937b6, 0xfdfb64f4, 0xfdfd818d, 0xfdff8dd0,
-	0xfe018a08, 0xfe03767a, 0xfe05536c, 0xfe07211c, 0xfe08dfc9,
-	0xfe0a8fab, 0xfe0c30fb, 0xfe0dc3ec, 0xfe0f48b1, 0xfe10bf76,
-	0xfe122869, 0xfe1383b4, 0xfe14d17c, 0xfe1611e7, 0xfe174516,
-	0xfe186b2a, 0xfe19843e, 0xfe1a9070, 0xfe1b8fd6, 0xfe1c8289,
-	0xfe1d689b, 0xfe1e4220, 0xfe1f0f26, 0xfe1fcfbc, 0xfe2083ed,
-	0xfe212bc3, 0xfe21c745, 0xfe225678, 0xfe22d95f, 0xfe234ffb,
-	0xfe23ba4a, 0xfe241849, 0xfe2469f2, 0xfe24af3c, 0xfe24e81e,
-	0xfe25148b, 0xfe253474, 0xfe2547c7, 0xfe254e70, 0xfe25485a,
-	0xfe25356a, 0xfe251586, 0xfe24e88f, 0xfe24ae64, 0xfe2466e1,
-	0xfe2411df, 0xfe23af34, 0xfe233eb4, 0xfe22c02c, 0xfe22336b,
-	0xfe219838, 0xfe20ee58, 0xfe20358c, 0xfe1f6d92, 0xfe1e9621,
-	0xfe1daef0, 0xfe1cb7ac, 0xfe1bb002, 0xfe1a9798, 0xfe196e0d,
-	0xfe1832fd, 0xfe16e5fe, 0xfe15869d, 0xfe141464, 0xfe128ed3,
-	0xfe10f565, 0xfe0f478c, 0xfe0d84b1, 0xfe0bac36, 0xfe09bd73,
-	0xfe07b7b5, 0xfe059a40, 0xfe03644c, 0xfe011504, 0xfdfeab88,
-	0xfdfc26e9, 0xfdf98629, 0xfdf6c83b, 0xfdf3ec01, 0xfdf0f04a,
-	0xfdedd3d1, 0xfdea953d, 0xfde7331e, 0xfde3abe9, 0xfddffdfb,
-	0xfddc2791, 0xfdd826cd, 0xfdd3f9a8, 0xfdcf9dfc, 0xfdcb1176,
-	0xfdc65198, 0xfdc15bb3, 0xfdbc2ce2, 0xfdb6c206, 0xfdb117be,
-	0xfdab2a63, 0xfda4f5fd, 0xfd9e7640, 0xfd97a67a, 0xfd908192,
-	0xfd8901f2, 0xfd812182, 0xfd78d98e, 0xfd7022bb, 0xfd66f4ed,
-	0xfd5d4732, 0xfd530f9c, 0xfd48432b, 0xfd3cd59a, 0xfd30b936,
-	0xfd23dea4, 0xfd16349e, 0xfd07a7a3, 0xfcf8219b, 0xfce7895b,
-	0xfcd5c220, 0xfcc2aadb, 0xfcae1d5e, 0xfc97ed4e, 0xfc7fe6d4,
-	0xfc65ccf3, 0xfc495762, 0xfc2a2fc8, 0xfc07ee19, 0xfbe213c1,
-	0xfbb8051a, 0xfb890078, 0xfb5411a5, 0xfb180005, 0xfad33482,
-	0xfa839276, 0xfa263b32, 0xf9b72d1c, 0xf930a1a2, 0xf889f023,
-	0xf7b577d2, 0xf69c650c, 0xf51530f0, 0xf2cb0e3c, 0xeeefb15d,
-	0xe6da6ecf,
-}
-var we = [256]float32{
-	2.0249555e-09, 1.486674e-11, 2.4409617e-11, 3.1968806e-11,
-	3.844677e-11, 4.4228204e-11, 4.9516443e-11, 5.443359e-11,
-	5.905944e-11, 6.344942e-11, 6.7643814e-11, 7.1672945e-11,
-	7.556032e-11, 7.932458e-11, 8.298079e-11, 8.654132e-11,
-	9.0016515e-11, 9.3415074e-11, 9.674443e-11, 1.0001099e-10,
-	1.03220314e-10, 1.06377254e-10, 1.09486115e-10, 1.1255068e-10,
-	1.1557435e-10, 1.1856015e-10, 1.2151083e-10, 1.2442886e-10,
-	1.2731648e-10, 1.3017575e-10, 1.3300853e-10, 1.3581657e-10,
-	1.3860142e-10, 1.4136457e-10, 1.4410738e-10, 1.4683108e-10,
-	1.4953687e-10, 1.5222583e-10, 1.54899e-10, 1.5755733e-10,
-	1.6020171e-10, 1.6283301e-10, 1.6545203e-10, 1.6805951e-10,
-	1.7065617e-10, 1.732427e-10, 1.7581973e-10, 1.7838787e-10,
-	1.8094774e-10, 1.8349985e-10, 1.8604476e-10, 1.8858298e-10,
-	1.9111498e-10, 1.9364126e-10, 1.9616223e-10, 1.9867835e-10,
-	2.0119004e-10, 2.0369768e-10, 2.0620168e-10, 2.087024e-10,
-	2.1120022e-10, 2.136955e-10, 2.1618855e-10, 2.1867974e-10,
-	2.2116936e-10, 2.2365775e-10, 2.261452e-10, 2.2863202e-10,
-	2.311185e-10, 2.3360494e-10, 2.360916e-10, 2.3857874e-10,
-	2.4106667e-10, 2.4355562e-10, 2.4604588e-10, 2.485377e-10,
-	2.5103128e-10, 2.5352695e-10, 2.560249e-10, 2.585254e-10,
-	2.6102867e-10, 2.6353494e-10, 2.6604446e-10, 2.6855745e-10,
-	2.7107416e-10, 2.7359479e-10, 2.761196e-10, 2.7864877e-10,
-	2.8118255e-10, 2.8372119e-10, 2.8626485e-10, 2.888138e-10,
-	2.9136826e-10, 2.939284e-10, 2.9649452e-10, 2.9906677e-10,
-	3.016454e-10, 3.0423064e-10, 3.0682268e-10, 3.0942177e-10,
-	3.1202813e-10, 3.1464195e-10, 3.1726352e-10, 3.19893e-10,
-	3.2253064e-10, 3.251767e-10, 3.2783135e-10, 3.3049485e-10,
-	3.3316744e-10, 3.3584938e-10, 3.3854083e-10, 3.4124212e-10,
-	3.4395342e-10, 3.46675e-10, 3.4940711e-10, 3.5215003e-10,
-	3.5490397e-10, 3.5766917e-10, 3.6044595e-10, 3.6323455e-10,
-	3.660352e-10, 3.6884823e-10, 3.7167386e-10, 3.745124e-10,
-	3.773641e-10, 3.802293e-10, 3.8310827e-10, 3.860013e-10,
-	3.8890866e-10, 3.918307e-10, 3.9476775e-10, 3.9772008e-10,
-	4.0068804e-10, 4.0367196e-10, 4.0667217e-10, 4.09689e-10,
-	4.1272286e-10, 4.1577405e-10, 4.1884296e-10, 4.2192994e-10,
-	4.250354e-10, 4.281597e-10, 4.313033e-10, 4.3446652e-10,
-	4.3764986e-10, 4.408537e-10, 4.4407847e-10, 4.4732465e-10,
-	4.5059267e-10, 4.5388301e-10, 4.571962e-10, 4.6053267e-10,
-	4.6389292e-10, 4.6727755e-10, 4.70687e-10, 4.741219e-10,
-	4.7758275e-10, 4.810702e-10, 4.845848e-10, 4.8812715e-10,
-	4.9169796e-10, 4.9529775e-10, 4.989273e-10, 5.0258725e-10,
-	5.0627835e-10, 5.100013e-10, 5.1375687e-10, 5.1754584e-10,
-	5.21369e-10, 5.2522725e-10, 5.2912136e-10, 5.330522e-10,
-	5.370208e-10, 5.4102806e-10, 5.45075e-10, 5.491625e-10,
-	5.532918e-10, 5.5746385e-10, 5.616799e-10, 5.6594107e-10,
-	5.7024857e-10, 5.746037e-10, 5.7900773e-10, 5.834621e-10,
-	5.8796823e-10, 5.925276e-10, 5.971417e-10, 6.018122e-10,
-	6.065408e-10, 6.113292e-10, 6.1617933e-10, 6.2109295e-10,
-	6.260722e-10, 6.3111916e-10, 6.3623595e-10, 6.4142497e-10,
-	6.4668854e-10, 6.5202926e-10, 6.5744976e-10, 6.6295286e-10,
-	6.6854156e-10, 6.742188e-10, 6.79988e-10, 6.858526e-10,
-	6.9181616e-10, 6.978826e-10, 7.04056e-10, 7.103407e-10,
-	7.167412e-10, 7.2326256e-10, 7.2990985e-10, 7.366886e-10,
-	7.4360473e-10, 7.5066453e-10, 7.5787476e-10, 7.6524265e-10,
-	7.7277595e-10, 7.80483e-10, 7.883728e-10, 7.9645507e-10,
-	8.047402e-10, 8.1323964e-10, 8.219657e-10, 8.309319e-10,
-	8.401528e-10, 8.496445e-10, 8.594247e-10, 8.6951274e-10,
-	8.799301e-10, 8.9070046e-10, 9.018503e-10, 9.134092e-10,
-	9.254101e-10, 9.378904e-10, 9.508923e-10, 9.644638e-10,
-	9.786603e-10, 9.935448e-10, 1.0091913e-09, 1.025686e-09,
-	1.0431306e-09, 1.0616465e-09, 1.08138e-09, 1.1025096e-09,
-	1.1252564e-09, 1.1498986e-09, 1.1767932e-09, 1.206409e-09,
-	1.2393786e-09, 1.276585e-09, 1.3193139e-09, 1.3695435e-09,
-	1.4305498e-09, 1.508365e-09, 1.6160854e-09, 1.7921248e-09,
-}
-var fe = [256]float32{
-	1, 0.9381437, 0.90046996, 0.87170434, 0.8477855, 0.8269933,
-	0.8084217, 0.7915276, 0.77595687, 0.7614634, 0.7478686,
-	0.7350381, 0.72286767, 0.71127474, 0.70019263, 0.6895665,
-	0.67935055, 0.6695063, 0.66000086, 0.65080583, 0.6418967,
-	0.63325197, 0.6248527, 0.6166822, 0.60872537, 0.60096896,
-	0.5934009, 0.58601034, 0.5787874, 0.57172304, 0.5648092,
-	0.5580383, 0.5514034, 0.5448982, 0.5385169, 0.53225386,
-	0.5261042, 0.52006316, 0.5141264, 0.50828975, 0.5025495,
-	0.496902, 0.49134386, 0.485872, 0.48048335, 0.4751752,
-	0.46994483, 0.46478975, 0.45970762, 0.45469615, 0.44975325,
-	0.44487688, 0.44006512, 0.43531612, 0.43062815, 0.42599955,
-	0.42142874, 0.4169142, 0.41245446, 0.40804818, 0.403694,
-	0.3993907, 0.39513698, 0.39093173, 0.38677382, 0.38266218,
-	0.37859577, 0.37457356, 0.37059465, 0.3666581, 0.362763,
-	0.35890847, 0.35509375, 0.351318, 0.3475805, 0.34388044,
-	0.34021714, 0.3365899, 0.33299807, 0.32944095, 0.32591796,
-	0.3224285, 0.3189719, 0.31554767, 0.31215525, 0.30879408,
-	0.3054636, 0.3021634, 0.29889292, 0.2956517, 0.29243928,
-	0.28925523, 0.28609908, 0.28297043, 0.27986884, 0.27679393,
-	0.2737453, 0.2707226, 0.2677254, 0.26475343, 0.26180625,
-	0.25888354, 0.25598502, 0.2531103, 0.25025907, 0.24743107,
-	0.24462597, 0.24184346, 0.23908329, 0.23634516, 0.23362878,
-	0.23093392, 0.2282603, 0.22560766, 0.22297576, 0.22036438,
-	0.21777324, 0.21520215, 0.21265087, 0.21011916, 0.20760682,
-	0.20511365, 0.20263945, 0.20018397, 0.19774707, 0.19532852,
-	0.19292815, 0.19054577, 0.1881812, 0.18583426, 0.18350479,
-	0.1811926, 0.17889754, 0.17661946, 0.17435817, 0.17211354,
-	0.1698854, 0.16767362, 0.16547804, 0.16329853, 0.16113494,
-	0.15898713, 0.15685499, 0.15473837, 0.15263714, 0.15055119,
-	0.14848037, 0.14642459, 0.14438373, 0.14235765, 0.14034624,
-	0.13834943, 0.13636707, 0.13439907, 0.13244532, 0.13050574,
-	0.1285802, 0.12666863, 0.12477092, 0.12288698, 0.12101672,
-	0.119160056, 0.1173169, 0.115487166, 0.11367077, 0.11186763,
-	0.11007768, 0.10830083, 0.10653701, 0.10478614, 0.10304816,
-	0.101323, 0.09961058, 0.09791085, 0.09622374, 0.09454919,
-	0.09288713, 0.091237515, 0.08960028, 0.087975375, 0.08636274,
-	0.08476233, 0.083174095, 0.081597984, 0.08003395, 0.07848195,
-	0.076941945, 0.07541389, 0.07389775, 0.072393484, 0.07090106,
-	0.069420435, 0.06795159, 0.066494495, 0.06504912, 0.063615434,
-	0.062193416, 0.060783047, 0.059384305, 0.057997175,
-	0.05662164, 0.05525769, 0.053905312, 0.052564494, 0.051235236,
-	0.049917534, 0.048611384, 0.047316793, 0.046033762, 0.0447623,
-	0.043502413, 0.042254124, 0.041017443, 0.039792392,
-	0.038578995, 0.037377283, 0.036187284, 0.035009038,
-	0.033842582, 0.032687962, 0.031545233, 0.030414443, 0.02929566,
-	0.02818895, 0.027094385, 0.026012046, 0.024942026, 0.023884421,
-	0.022839336, 0.021806888, 0.020787204, 0.019780423, 0.0187867,
-	0.0178062, 0.016839107, 0.015885621, 0.014945968, 0.014020392,
-	0.013109165, 0.012212592, 0.011331013, 0.01046481, 0.009614414,
-	0.008780315, 0.007963077, 0.0071633533, 0.006381906,
-	0.0056196423, 0.0048776558, 0.004157295, 0.0034602648,
-	0.0027887989, 0.0021459677, 0.0015362998, 0.0009672693,
-	0.00045413437,
-}
diff --git a/contrib/go/_std_1.18/src/math/rand/normal.go b/contrib/go/_std_1.18/src/math/rand/normal.go
deleted file mode 100644
index 2c5a7aa99b..0000000000
--- a/contrib/go/_std_1.18/src/math/rand/normal.go
+++ /dev/null
@@ -1,157 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package rand
-
-import (
-	"math"
-)
-
-/*
- * Normal distribution
- *
- * See "The Ziggurat Method for Generating Random Variables"
- * (Marsaglia & Tsang, 2000)
- * http://www.jstatsoft.org/v05/i08/paper [pdf]
- */
-
-const (
-	rn = 3.442619855899
-)
-
-func absInt32(i int32) uint32 {
-	if i < 0 {
-		return uint32(-i)
-	}
-	return uint32(i)
-}
-
-// NormFloat64 returns a normally distributed float64 in
-// the range -math.MaxFloat64 through +math.MaxFloat64 inclusive,
-// with standard normal distribution (mean = 0, stddev = 1).
-// To produce a different normal distribution, callers can
-// adjust the output using:
-//
-//  sample = NormFloat64() * desiredStdDev + desiredMean
-//
-func (r *Rand) NormFloat64() float64 {
-	for {
-		j := int32(r.Uint32()) // Possibly negative
-		i := j & 0x7F
-		x := float64(j) * float64(wn[i])
-		if absInt32(j) < kn[i] {
-			// This case should be hit better than 99% of the time.
-			return x
-		}
-
-		if i == 0 {
-			// This extra work is only required for the base strip.
-			for {
-				x = -math.Log(r.Float64()) * (1.0 / rn)
-				y := -math.Log(r.Float64())
-				if y+y >= x*x {
-					break
-				}
-			}
-			if j > 0 {
-				return rn + x
-			}
-			return -rn - x
-		}
-		if fn[i]+float32(r.Float64())*(fn[i-1]-fn[i]) < float32(math.Exp(-.5*x*x)) {
-			return x
-		}
-	}
-}
-
-var kn = [128]uint32{
-	0x76ad2212, 0x0, 0x600f1b53, 0x6ce447a6, 0x725b46a2,
-	0x7560051d, 0x774921eb, 0x789a25bd, 0x799045c3, 0x7a4bce5d,
-	0x7adf629f, 0x7b5682a6, 0x7bb8a8c6, 0x7c0ae722, 0x7c50cce7,
-	0x7c8cec5b, 0x7cc12cd6, 0x7ceefed2, 0x7d177e0b, 0x7d3b8883,
-	0x7d5bce6c, 0x7d78dd64, 0x7d932886, 0x7dab0e57, 0x7dc0dd30,
-	0x7dd4d688, 0x7de73185, 0x7df81cea, 0x7e07c0a3, 0x7e163efa,
-	0x7e23b587, 0x7e303dfd, 0x7e3beec2, 0x7e46db77, 0x7e51155d,
-	0x7e5aabb3, 0x7e63abf7, 0x7e6c222c, 0x7e741906, 0x7e7b9a18,
-	0x7e82adfa, 0x7e895c63, 0x7e8fac4b, 0x7e95a3fb, 0x7e9b4924,
-	0x7ea0a0ef, 0x7ea5b00d, 0x7eaa7ac3, 0x7eaf04f3, 0x7eb3522a,
-	0x7eb765a5, 0x7ebb4259, 0x7ebeeafd, 0x7ec2620a, 0x7ec5a9c4,
-	0x7ec8c441, 0x7ecbb365, 0x7ece78ed, 0x7ed11671, 0x7ed38d62,
-	0x7ed5df12, 0x7ed80cb4, 0x7eda175c, 0x7edc0005, 0x7eddc78e,
-	0x7edf6ebf, 0x7ee0f647, 0x7ee25ebe, 0x7ee3a8a9, 0x7ee4d473,
-	0x7ee5e276, 0x7ee6d2f5, 0x7ee7a620, 0x7ee85c10, 0x7ee8f4cd,
-	0x7ee97047, 0x7ee9ce59, 0x7eea0eca, 0x7eea3147, 0x7eea3568,
-	0x7eea1aab, 0x7ee9e071, 0x7ee98602, 0x7ee90a88, 0x7ee86d08,
-	0x7ee7ac6a, 0x7ee6c769, 0x7ee5bc9c, 0x7ee48a67, 0x7ee32efc,
-	0x7ee1a857, 0x7edff42f, 0x7ede0ffa, 0x7edbf8d9, 0x7ed9ab94,
-	0x7ed7248d, 0x7ed45fae, 0x7ed1585c, 0x7ece095f, 0x7eca6ccb,
-	0x7ec67be2, 0x7ec22eee, 0x7ebd7d1a, 0x7eb85c35, 0x7eb2c075,
-	0x7eac9c20, 0x7ea5df27, 0x7e9e769f, 0x7e964c16, 0x7e8d44ba,
-	0x7e834033, 0x7e781728, 0x7e6b9933, 0x7e5d8a1a, 0x7e4d9ded,
-	0x7e3b737a, 0x7e268c2f, 0x7e0e3ff5, 0x7df1aa5d, 0x7dcf8c72,
-	0x7da61a1e, 0x7d72a0fb, 0x7d30e097, 0x7cd9b4ab, 0x7c600f1a,
-	0x7ba90bdc, 0x7a722176, 0x77d664e5,
-}
-var wn = [128]float32{
-	1.7290405e-09, 1.2680929e-10, 1.6897518e-10, 1.9862688e-10,
-	2.2232431e-10, 2.4244937e-10, 2.601613e-10, 2.7611988e-10,
-	2.9073963e-10, 3.042997e-10, 3.1699796e-10, 3.289802e-10,
-	3.4035738e-10, 3.5121603e-10, 3.616251e-10, 3.7164058e-10,
-	3.8130857e-10, 3.9066758e-10, 3.9975012e-10, 4.08584e-10,
-	4.1719309e-10, 4.2559822e-10, 4.338176e-10, 4.418672e-10,
-	4.497613e-10, 4.5751258e-10, 4.651324e-10, 4.7263105e-10,
-	4.8001775e-10, 4.87301e-10, 4.944885e-10, 5.015873e-10,
-	5.0860405e-10, 5.155446e-10, 5.2241467e-10, 5.2921934e-10,
-	5.359635e-10, 5.426517e-10, 5.4928817e-10, 5.5587696e-10,
-	5.624219e-10, 5.6892646e-10, 5.753941e-10, 5.818282e-10,
-	5.882317e-10, 5.946077e-10, 6.00959e-10, 6.072884e-10,
-	6.135985e-10, 6.19892e-10, 6.2617134e-10, 6.3243905e-10,
-	6.386974e-10, 6.449488e-10, 6.511956e-10, 6.5744005e-10,
-	6.6368433e-10, 6.699307e-10, 6.7618144e-10, 6.824387e-10,
-	6.8870465e-10, 6.949815e-10, 7.012715e-10, 7.075768e-10,
-	7.1389966e-10, 7.202424e-10, 7.266073e-10, 7.329966e-10,
-	7.394128e-10, 7.4585826e-10, 7.5233547e-10, 7.58847e-10,
-	7.653954e-10, 7.719835e-10, 7.7861395e-10, 7.852897e-10,
-	7.920138e-10, 7.987892e-10, 8.0561924e-10, 8.125073e-10,
-	8.194569e-10, 8.2647167e-10, 8.3355556e-10, 8.407127e-10,
-	8.479473e-10, 8.55264e-10, 8.6266755e-10, 8.7016316e-10,
-	8.777562e-10, 8.8545243e-10, 8.932582e-10, 9.0117996e-10,
-	9.09225e-10, 9.174008e-10, 9.2571584e-10, 9.341788e-10,
-	9.427997e-10, 9.515889e-10, 9.605579e-10, 9.697193e-10,
-	9.790869e-10, 9.88676e-10, 9.985036e-10, 1.0085882e-09,
-	1.0189509e-09, 1.0296151e-09, 1.0406069e-09, 1.0519566e-09,
-	1.063698e-09, 1.0758702e-09, 1.0885183e-09, 1.1016947e-09,
-	1.1154611e-09, 1.1298902e-09, 1.1450696e-09, 1.1611052e-09,
-	1.1781276e-09, 1.1962995e-09, 1.2158287e-09, 1.2369856e-09,
-	1.2601323e-09, 1.2857697e-09, 1.3146202e-09, 1.347784e-09,
-	1.3870636e-09, 1.4357403e-09, 1.5008659e-09, 1.6030948e-09,
-}
-var fn = [128]float32{
-	1, 0.9635997, 0.9362827, 0.9130436, 0.89228165, 0.87324303,
-	0.8555006, 0.8387836, 0.8229072, 0.8077383, 0.793177,
-	0.7791461, 0.7655842, 0.7524416, 0.73967725, 0.7272569,
-	0.7151515, 0.7033361, 0.69178915, 0.68049186, 0.6694277,
-	0.658582, 0.6479418, 0.63749546, 0.6272325, 0.6171434,
-	0.6072195, 0.5974532, 0.58783704, 0.5783647, 0.56903,
-	0.5598274, 0.5507518, 0.54179835, 0.5329627, 0.52424055,
-	0.5156282, 0.50712204, 0.49871865, 0.49041483, 0.48220766,
-	0.4740943, 0.46607214, 0.4581387, 0.45029163, 0.44252872,
-	0.43484783, 0.427247, 0.41972435, 0.41227803, 0.40490642,
-	0.39760786, 0.3903808, 0.3832238, 0.37613547, 0.36911446,
-	0.3621595, 0.35526937, 0.34844297, 0.34167916, 0.33497685,
-	0.3283351, 0.3217529, 0.3152294, 0.30876362, 0.30235484,
-	0.29600215, 0.28970486, 0.2834622, 0.2772735, 0.27113807,
-	0.2650553, 0.25902456, 0.2530453, 0.24711695, 0.241239,
-	0.23541094, 0.22963232, 0.2239027, 0.21822165, 0.21258877,
-	0.20700371, 0.20146611, 0.19597565, 0.19053204, 0.18513499,
-	0.17978427, 0.17447963, 0.1692209, 0.16400786, 0.15884037,
-	0.15371831, 0.14864157, 0.14361008, 0.13862377, 0.13368265,
-	0.12878671, 0.12393598, 0.119130544, 0.11437051, 0.10965602,
-	0.104987256, 0.10036444, 0.095787846, 0.0912578, 0.08677467,
-	0.0823389, 0.077950984, 0.073611505, 0.06932112, 0.06508058,
-	0.06089077, 0.056752663, 0.0526674, 0.048636295, 0.044660863,
-	0.040742867, 0.03688439, 0.033087887, 0.029356318,
-	0.025693292, 0.022103304, 0.018592102, 0.015167298,
-	0.011839478, 0.008624485, 0.005548995, 0.0026696292,
-}
diff --git a/contrib/go/_std_1.18/src/math/rand/rand.go b/contrib/go/_std_1.18/src/math/rand/rand.go
deleted file mode 100644
index 13f20ca5ef..0000000000
--- a/contrib/go/_std_1.18/src/math/rand/rand.go
+++ /dev/null
@@ -1,421 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package rand implements pseudo-random number generators unsuitable for
-// security-sensitive work.
-//
-// Random numbers are generated by a Source. Top-level functions, such as
-// Float64 and Int, use a default shared Source that produces a deterministic
-// sequence of values each time a program is run. Use the Seed function to
-// initialize the default Source if different behavior is required for each run.
-// The default Source is safe for concurrent use by multiple goroutines, but
-// Sources created by NewSource are not.
-//
-// This package's outputs might be easily predictable regardless of how it's
-// seeded. For random numbers suitable for security-sensitive work, see the
-// crypto/rand package.
-package rand
-
-import "sync"
-
-// A Source represents a source of uniformly-distributed
-// pseudo-random int64 values in the range [0, 1<<63).
-type Source interface {
-	Int63() int64
-	Seed(seed int64)
-}
-
-// A Source64 is a Source that can also generate
-// uniformly-distributed pseudo-random uint64 values in
-// the range [0, 1<<64) directly.
-// If a Rand r's underlying Source s implements Source64,
-// then r.Uint64 returns the result of one call to s.Uint64
-// instead of making two calls to s.Int63.
-type Source64 interface {
-	Source
-	Uint64() uint64
-}
-
-// NewSource returns a new pseudo-random Source seeded with the given value.
-// Unlike the default Source used by top-level functions, this source is not
-// safe for concurrent use by multiple goroutines.
-func NewSource(seed int64) Source {
-	var rng rngSource
-	rng.Seed(seed)
-	return &rng
-}
-
-// A Rand is a source of random numbers.
-type Rand struct {
-	src Source
-	s64 Source64 // non-nil if src is source64
-
-	// readVal contains remainder of 63-bit integer used for bytes
-	// generation during most recent Read call.
-	// It is saved so next Read call can start where the previous
-	// one finished.
-	readVal int64
-	// readPos indicates the number of low-order bytes of readVal
-	// that are still valid.
-	readPos int8
-}
-
-// New returns a new Rand that uses random values from src
-// to generate other random values.
-func New(src Source) *Rand {
-	s64, _ := src.(Source64)
-	return &Rand{src: src, s64: s64}
-}
-
-// Seed uses the provided seed value to initialize the generator to a deterministic state.
-// Seed should not be called concurrently with any other Rand method.
-func (r *Rand) Seed(seed int64) {
-	if lk, ok := r.src.(*lockedSource); ok {
-		lk.seedPos(seed, &r.readPos)
-		return
-	}
-
-	r.src.Seed(seed)
-	r.readPos = 0
-}
-
-// Int63 returns a non-negative pseudo-random 63-bit integer as an int64.
-func (r *Rand) Int63() int64 { return r.src.Int63() }
-
-// Uint32 returns a pseudo-random 32-bit value as a uint32.
-func (r *Rand) Uint32() uint32 { return uint32(r.Int63() >> 31) }
-
-// Uint64 returns a pseudo-random 64-bit value as a uint64.
-func (r *Rand) Uint64() uint64 {
-	if r.s64 != nil {
-		return r.s64.Uint64()
-	}
-	return uint64(r.Int63())>>31 | uint64(r.Int63())<<32
-}
-
-// Int31 returns a non-negative pseudo-random 31-bit integer as an int32.
-func (r *Rand) Int31() int32 { return int32(r.Int63() >> 32) }
-
-// Int returns a non-negative pseudo-random int.
-func (r *Rand) Int() int {
-	u := uint(r.Int63())
-	return int(u << 1 >> 1) // clear sign bit if int == int32
-}
-
-// Int63n returns, as an int64, a non-negative pseudo-random number in the half-open interval [0,n).
-// It panics if n <= 0.
-func (r *Rand) Int63n(n int64) int64 {
-	if n <= 0 {
-		panic("invalid argument to Int63n")
-	}
-	if n&(n-1) == 0 { // n is power of two, can mask
-		return r.Int63() & (n - 1)
-	}
-	max := int64((1 << 63) - 1 - (1<<63)%uint64(n))
-	v := r.Int63()
-	for v > max {
-		v = r.Int63()
-	}
-	return v % n
-}
-
-// Int31n returns, as an int32, a non-negative pseudo-random number in the half-open interval [0,n).
-// It panics if n <= 0.
-func (r *Rand) Int31n(n int32) int32 {
-	if n <= 0 {
-		panic("invalid argument to Int31n")
-	}
-	if n&(n-1) == 0 { // n is power of two, can mask
-		return r.Int31() & (n - 1)
-	}
-	max := int32((1 << 31) - 1 - (1<<31)%uint32(n))
-	v := r.Int31()
-	for v > max {
-		v = r.Int31()
-	}
-	return v % n
-}
-
-// int31n returns, as an int32, a non-negative pseudo-random number in the half-open interval [0,n).
-// n must be > 0, but int31n does not check this; the caller must ensure it.
-// int31n exists because Int31n is inefficient, but Go 1 compatibility
-// requires that the stream of values produced by math/rand remain unchanged.
-// int31n can thus only be used internally, by newly introduced APIs.
-//
-// For implementation details, see:
-// https://lemire.me/blog/2016/06/27/a-fast-alternative-to-the-modulo-reduction
-// https://lemire.me/blog/2016/06/30/fast-random-shuffling
-func (r *Rand) int31n(n int32) int32 {
-	v := r.Uint32()
-	prod := uint64(v) * uint64(n)
-	low := uint32(prod)
-	if low < uint32(n) {
-		thresh := uint32(-n) % uint32(n)
-		for low < thresh {
-			v = r.Uint32()
-			prod = uint64(v) * uint64(n)
-			low = uint32(prod)
-		}
-	}
-	return int32(prod >> 32)
-}
-
-// Intn returns, as an int, a non-negative pseudo-random number in the half-open interval [0,n).
-// It panics if n <= 0.
-func (r *Rand) Intn(n int) int {
-	if n <= 0 {
-		panic("invalid argument to Intn")
-	}
-	if n <= 1<<31-1 {
-		return int(r.Int31n(int32(n)))
-	}
-	return int(r.Int63n(int64(n)))
-}
-
-// Float64 returns, as a float64, a pseudo-random number in the half-open interval [0.0,1.0).
-func (r *Rand) Float64() float64 {
-	// A clearer, simpler implementation would be:
-	//	return float64(r.Int63n(1<<53)) / (1<<53)
-	// However, Go 1 shipped with
-	//	return float64(r.Int63()) / (1 << 63)
-	// and we want to preserve that value stream.
-	//
-	// There is one bug in the value stream: r.Int63() may be so close
-	// to 1<<63 that the division rounds up to 1.0, and we've guaranteed
-	// that the result is always less than 1.0.
-	//
-	// We tried to fix this by mapping 1.0 back to 0.0, but since float64
-	// values near 0 are much denser than near 1, mapping 1 to 0 caused
-	// a theoretically significant overshoot in the probability of returning 0.
-	// Instead of that, if we round up to 1, just try again.
-	// Getting 1 only happens 1/2⁵³ of the time, so most clients
-	// will not observe it anyway.
-again:
-	f := float64(r.Int63()) / (1 << 63)
-	if f == 1 {
-		goto again // resample; this branch is taken O(never)
-	}
-	return f
-}
-
-// Float32 returns, as a float32, a pseudo-random number in the half-open interval [0.0,1.0).
-func (r *Rand) Float32() float32 {
-	// Same rationale as in Float64: we want to preserve the Go 1 value
-	// stream except we want to fix it not to return 1.0
-	// This only happens 1/2²⁴ of the time (plus the 1/2⁵³ of the time in Float64).
-again:
-	f := float32(r.Float64())
-	if f == 1 {
-		goto again // resample; this branch is taken O(very rarely)
-	}
-	return f
-}
-
-// Perm returns, as a slice of n ints, a pseudo-random permutation of the integers
-// in the half-open interval [0,n).
-func (r *Rand) Perm(n int) []int {
-	m := make([]int, n)
-	// In the following loop, the iteration when i=0 always swaps m[0] with m[0].
-	// A change to remove this useless iteration is to assign 1 to i in the init
-	// statement. But Perm also effects r. Making this change will affect
-	// the final state of r. So this change can't be made for compatibility
-	// reasons for Go 1.
-	for i := 0; i < n; i++ {
-		j := r.Intn(i + 1)
-		m[i] = m[j]
-		m[j] = i
-	}
-	return m
-}
-
-// Shuffle pseudo-randomizes the order of elements.
-// n is the number of elements. Shuffle panics if n < 0.
-// swap swaps the elements with indexes i and j.
-func (r *Rand) Shuffle(n int, swap func(i, j int)) {
-	if n < 0 {
-		panic("invalid argument to Shuffle")
-	}
-
-	// Fisher-Yates shuffle: https://en.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle
-	// Shuffle really ought not be called with n that doesn't fit in 32 bits.
-	// Not only will it take a very long time, but with 2³¹! possible permutations,
-	// there's no way that any PRNG can have a big enough internal state to
-	// generate even a minuscule percentage of the possible permutations.
-	// Nevertheless, the right API signature accepts an int n, so handle it as best we can.
-	i := n - 1
-	for ; i > 1<<31-1-1; i-- {
-		j := int(r.Int63n(int64(i + 1)))
-		swap(i, j)
-	}
-	for ; i > 0; i-- {
-		j := int(r.int31n(int32(i + 1)))
-		swap(i, j)
-	}
-}
-
-// Read generates len(p) random bytes and writes them into p. It
-// always returns len(p) and a nil error.
-// Read should not be called concurrently with any other Rand method.
-func (r *Rand) Read(p []byte) (n int, err error) {
-	if lk, ok := r.src.(*lockedSource); ok {
-		return lk.read(p, &r.readVal, &r.readPos)
-	}
-	return read(p, r.src, &r.readVal, &r.readPos)
-}
-
-func read(p []byte, src Source, readVal *int64, readPos *int8) (n int, err error) {
-	pos := *readPos
-	val := *readVal
-	rng, _ := src.(*rngSource)
-	for n = 0; n < len(p); n++ {
-		if pos == 0 {
-			if rng != nil {
-				val = rng.Int63()
-			} else {
-				val = src.Int63()
-			}
-			pos = 7
-		}
-		p[n] = byte(val)
-		val >>= 8
-		pos--
-	}
-	*readPos = pos
-	*readVal = val
-	return
-}
-
-/*
- * Top-level convenience functions
- */
-
-var globalRand = New(&lockedSource{src: NewSource(1).(*rngSource)})
-
-// Type assert that globalRand's source is a lockedSource whose src is a *rngSource.
-var _ *rngSource = globalRand.src.(*lockedSource).src
-
-// Seed uses the provided seed value to initialize the default Source to a
-// deterministic state. If Seed is not called, the generator behaves as
-// if seeded by Seed(1). Seed values that have the same remainder when
-// divided by 2³¹-1 generate the same pseudo-random sequence.
-// Seed, unlike the Rand.Seed method, is safe for concurrent use.
-func Seed(seed int64) { globalRand.Seed(seed) }
-
-// Int63 returns a non-negative pseudo-random 63-bit integer as an int64
-// from the default Source.
-func Int63() int64 { return globalRand.Int63() }
-
-// Uint32 returns a pseudo-random 32-bit value as a uint32
-// from the default Source.
-func Uint32() uint32 { return globalRand.Uint32() }
-
-// Uint64 returns a pseudo-random 64-bit value as a uint64
-// from the default Source.
-func Uint64() uint64 { return globalRand.Uint64() }
-
-// Int31 returns a non-negative pseudo-random 31-bit integer as an int32
-// from the default Source.
-func Int31() int32 { return globalRand.Int31() }
-
-// Int returns a non-negative pseudo-random int from the default Source.
-func Int() int { return globalRand.Int() }
-
-// Int63n returns, as an int64, a non-negative pseudo-random number in the half-open interval [0,n)
-// from the default Source.
-// It panics if n <= 0.
-func Int63n(n int64) int64 { return globalRand.Int63n(n) }
-
-// Int31n returns, as an int32, a non-negative pseudo-random number in the half-open interval [0,n)
-// from the default Source.
-// It panics if n <= 0.
-func Int31n(n int32) int32 { return globalRand.Int31n(n) }
-
-// Intn returns, as an int, a non-negative pseudo-random number in the half-open interval [0,n)
-// from the default Source.
-// It panics if n <= 0.
-func Intn(n int) int { return globalRand.Intn(n) }
-
-// Float64 returns, as a float64, a pseudo-random number in the half-open interval [0.0,1.0)
-// from the default Source.
-func Float64() float64 { return globalRand.Float64() }
-
-// Float32 returns, as a float32, a pseudo-random number in the half-open interval [0.0,1.0)
-// from the default Source.
-func Float32() float32 { return globalRand.Float32() }
-
-// Perm returns, as a slice of n ints, a pseudo-random permutation of the integers
-// in the half-open interval [0,n) from the default Source.
-func Perm(n int) []int { return globalRand.Perm(n) }
-
-// Shuffle pseudo-randomizes the order of elements using the default Source.
-// n is the number of elements. Shuffle panics if n < 0.
-// swap swaps the elements with indexes i and j.
-func Shuffle(n int, swap func(i, j int)) { globalRand.Shuffle(n, swap) }
-
-// Read generates len(p) random bytes from the default Source and
-// writes them into p. It always returns len(p) and a nil error.
-// Read, unlike the Rand.Read method, is safe for concurrent use.
-func Read(p []byte) (n int, err error) { return globalRand.Read(p) }
-
-// NormFloat64 returns a normally distributed float64 in the range
-// [-math.MaxFloat64, +math.MaxFloat64] with
-// standard normal distribution (mean = 0, stddev = 1)
-// from the default Source.
-// To produce a different normal distribution, callers can
-// adjust the output using:
-//
-//  sample = NormFloat64() * desiredStdDev + desiredMean
-//
-func NormFloat64() float64 { return globalRand.NormFloat64() }
-
-// ExpFloat64 returns an exponentially distributed float64 in the range
-// (0, +math.MaxFloat64] with an exponential distribution whose rate parameter
-// (lambda) is 1 and whose mean is 1/lambda (1) from the default Source.
-// To produce a distribution with a different rate parameter,
-// callers can adjust the output using:
-//
-//  sample = ExpFloat64() / desiredRateParameter
-//
-func ExpFloat64() float64 { return globalRand.ExpFloat64() }
-
-type lockedSource struct {
-	lk  sync.Mutex
-	src *rngSource
-}
-
-func (r *lockedSource) Int63() (n int64) {
-	r.lk.Lock()
-	n = r.src.Int63()
-	r.lk.Unlock()
-	return
-}
-
-func (r *lockedSource) Uint64() (n uint64) {
-	r.lk.Lock()
-	n = r.src.Uint64()
-	r.lk.Unlock()
-	return
-}
-
-func (r *lockedSource) Seed(seed int64) {
-	r.lk.Lock()
-	r.src.Seed(seed)
-	r.lk.Unlock()
-}
-
-// seedPos implements Seed for a lockedSource without a race condition.
-func (r *lockedSource) seedPos(seed int64, readPos *int8) {
-	r.lk.Lock()
-	r.src.Seed(seed)
-	*readPos = 0
-	r.lk.Unlock()
-}
-
-// read implements Read for a lockedSource without a race condition.
-func (r *lockedSource) read(p []byte, readVal *int64, readPos *int8) (n int, err error) {
-	r.lk.Lock()
-	n, err = read(p, r.src, readVal, readPos)
-	r.lk.Unlock()
-	return
-}
diff --git a/contrib/go/_std_1.18/src/math/remainder.go b/contrib/go/_std_1.18/src/math/remainder.go
deleted file mode 100644
index bf8bfd5553..0000000000
--- a/contrib/go/_std_1.18/src/math/remainder.go
+++ /dev/null
@@ -1,94 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-// The original C code and the comment below are from
-// FreeBSD's /usr/src/lib/msun/src/e_remainder.c and came
-// with this notice. The go code is a simplified version of
-// the original C.
-//
-// ====================================================
-// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
-//
-// Developed at SunPro, a Sun Microsystems, Inc. business.
-// Permission to use, copy, modify, and distribute this
-// software is freely granted, provided that this notice
-// is preserved.
-// ====================================================
-//
-// __ieee754_remainder(x,y)
-// Return :
-//      returns  x REM y  =  x - [x/y]*y  as if in infinite
-//      precision arithmetic, where [x/y] is the (infinite bit)
-//      integer nearest x/y (in half way cases, choose the even one).
-// Method :
-//      Based on Mod() returning  x - [x/y]chopped * y  exactly.
-
-// Remainder returns the IEEE 754 floating-point remainder of x/y.
-//
-// Special cases are:
-//	Remainder(±Inf, y) = NaN
-//	Remainder(NaN, y) = NaN
-//	Remainder(x, 0) = NaN
-//	Remainder(x, ±Inf) = x
-//	Remainder(x, NaN) = NaN
-func Remainder(x, y float64) float64 {
-	if haveArchRemainder {
-		return archRemainder(x, y)
-	}
-	return remainder(x, y)
-}
-
-func remainder(x, y float64) float64 {
-	const (
-		Tiny    = 4.45014771701440276618e-308 // 0x0020000000000000
-		HalfMax = MaxFloat64 / 2
-	)
-	// special cases
-	switch {
-	case IsNaN(x) || IsNaN(y) || IsInf(x, 0) || y == 0:
-		return NaN()
-	case IsInf(y, 0):
-		return x
-	}
-	sign := false
-	if x < 0 {
-		x = -x
-		sign = true
-	}
-	if y < 0 {
-		y = -y
-	}
-	if x == y {
-		if sign {
-			zero := 0.0
-			return -zero
-		}
-		return 0
-	}
-	if y <= HalfMax {
-		x = Mod(x, y+y) // now x < 2y
-	}
-	if y < Tiny {
-		if x+x > y {
-			x -= y
-			if x+x >= y {
-				x -= y
-			}
-		}
-	} else {
-		yHalf := 0.5 * y
-		if x > yHalf {
-			x -= y
-			if x >= yHalf {
-				x -= y
-			}
-		}
-	}
-	if sign {
-		x = -x
-	}
-	return x
-}
diff --git a/contrib/go/_std_1.18/src/math/sin.go b/contrib/go/_std_1.18/src/math/sin.go
deleted file mode 100644
index d95bb548e8..0000000000
--- a/contrib/go/_std_1.18/src/math/sin.go
+++ /dev/null
@@ -1,242 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-/*
-	Floating-point sine and cosine.
-*/
-
-// The original C code, the long comment, and the constants
-// below were from http://netlib.sandia.gov/cephes/cmath/sin.c,
-// available from http://www.netlib.org/cephes/cmath.tgz.
-// The go code is a simplified version of the original C.
-//
-//      sin.c
-//
-//      Circular sine
-//
-// SYNOPSIS:
-//
-// double x, y, sin();
-// y = sin( x );
-//
-// DESCRIPTION:
-//
-// Range reduction is into intervals of pi/4.  The reduction error is nearly
-// eliminated by contriving an extended precision modular arithmetic.
-//
-// Two polynomial approximating functions are employed.
-// Between 0 and pi/4 the sine is approximated by
-//      x  +  x**3 P(x**2).
-// Between pi/4 and pi/2 the cosine is represented as
-//      1  -  x**2 Q(x**2).
-//
-// ACCURACY:
-//
-//                      Relative error:
-// arithmetic   domain      # trials      peak         rms
-//    DEC       0, 10       150000       3.0e-17     7.8e-18
-//    IEEE -1.07e9,+1.07e9  130000       2.1e-16     5.4e-17
-//
-// Partial loss of accuracy begins to occur at x = 2**30 = 1.074e9.  The loss
-// is not gradual, but jumps suddenly to about 1 part in 10e7.  Results may
-// be meaningless for x > 2**49 = 5.6e14.
-//
-//      cos.c
-//
-//      Circular cosine
-//
-// SYNOPSIS:
-//
-// double x, y, cos();
-// y = cos( x );
-//
-// DESCRIPTION:
-//
-// Range reduction is into intervals of pi/4.  The reduction error is nearly
-// eliminated by contriving an extended precision modular arithmetic.
-//
-// Two polynomial approximating functions are employed.
-// Between 0 and pi/4 the cosine is approximated by
-//      1  -  x**2 Q(x**2).
-// Between pi/4 and pi/2 the sine is represented as
-//      x  +  x**3 P(x**2).
-//
-// ACCURACY:
-//
-//                      Relative error:
-// arithmetic   domain      # trials      peak         rms
-//    IEEE -1.07e9,+1.07e9  130000       2.1e-16     5.4e-17
-//    DEC        0,+1.07e9   17000       3.0e-17     7.2e-18
-//
-// Cephes Math Library Release 2.8:  June, 2000
-// Copyright 1984, 1987, 1989, 1992, 2000 by Stephen L. Moshier
-//
-// The readme file at http://netlib.sandia.gov/cephes/ says:
-//    Some software in this archive may be from the book _Methods and
-// Programs for Mathematical Functions_ (Prentice-Hall or Simon & Schuster
-// International, 1989) or from the Cephes Mathematical Library, a
-// commercial product. In either event, it is copyrighted by the author.
-// What you see here may be used freely but it comes with no support or
-// guarantee.
-//
-//   The two known misprints in the book are repaired here in the
-// source listings for the gamma function and the incomplete beta
-// integral.
-//
-//   Stephen L. Moshier
-//   moshier@na-net.ornl.gov
-
-// sin coefficients
-var _sin = [...]float64{
-	1.58962301576546568060e-10, // 0x3de5d8fd1fd19ccd
-	-2.50507477628578072866e-8, // 0xbe5ae5e5a9291f5d
-	2.75573136213857245213e-6,  // 0x3ec71de3567d48a1
-	-1.98412698295895385996e-4, // 0xbf2a01a019bfdf03
-	8.33333333332211858878e-3,  // 0x3f8111111110f7d0
-	-1.66666666666666307295e-1, // 0xbfc5555555555548
-}
-
-// cos coefficients
-var _cos = [...]float64{
-	-1.13585365213876817300e-11, // 0xbda8fa49a0861a9b
-	2.08757008419747316778e-9,   // 0x3e21ee9d7b4e3f05
-	-2.75573141792967388112e-7,  // 0xbe927e4f7eac4bc6
-	2.48015872888517045348e-5,   // 0x3efa01a019c844f5
-	-1.38888888888730564116e-3,  // 0xbf56c16c16c14f91
-	4.16666666666665929218e-2,   // 0x3fa555555555554b
-}
-
-// Cos returns the cosine of the radian argument x.
-//
-// Special cases are:
-//	Cos(±Inf) = NaN
-//	Cos(NaN) = NaN
-func Cos(x float64) float64 {
-	if haveArchCos {
-		return archCos(x)
-	}
-	return cos(x)
-}
-
-func cos(x float64) float64 {
-	const (
-		PI4A = 7.85398125648498535156e-1  // 0x3fe921fb40000000, Pi/4 split into three parts
-		PI4B = 3.77489470793079817668e-8  // 0x3e64442d00000000,
-		PI4C = 2.69515142907905952645e-15 // 0x3ce8469898cc5170,
-	)
-	// special cases
-	switch {
-	case IsNaN(x) || IsInf(x, 0):
-		return NaN()
-	}
-
-	// make argument positive
-	sign := false
-	x = Abs(x)
-
-	var j uint64
-	var y, z float64
-	if x >= reduceThreshold {
-		j, z = trigReduce(x)
-	} else {
-		j = uint64(x * (4 / Pi)) // integer part of x/(Pi/4), as integer for tests on the phase angle
-		y = float64(j)           // integer part of x/(Pi/4), as float
-
-		// map zeros to origin
-		if j&1 == 1 {
-			j++
-			y++
-		}
-		j &= 7                               // octant modulo 2Pi radians (360 degrees)
-		z = ((x - y*PI4A) - y*PI4B) - y*PI4C // Extended precision modular arithmetic
-	}
-
-	if j > 3 {
-		j -= 4
-		sign = !sign
-	}
-	if j > 1 {
-		sign = !sign
-	}
-
-	zz := z * z
-	if j == 1 || j == 2 {
-		y = z + z*zz*((((((_sin[0]*zz)+_sin[1])*zz+_sin[2])*zz+_sin[3])*zz+_sin[4])*zz+_sin[5])
-	} else {
-		y = 1.0 - 0.5*zz + zz*zz*((((((_cos[0]*zz)+_cos[1])*zz+_cos[2])*zz+_cos[3])*zz+_cos[4])*zz+_cos[5])
-	}
-	if sign {
-		y = -y
-	}
-	return y
-}
-
-// Sin returns the sine of the radian argument x.
-//
-// Special cases are:
-//	Sin(±0) = ±0
-//	Sin(±Inf) = NaN
-//	Sin(NaN) = NaN
-func Sin(x float64) float64 {
-	if haveArchSin {
-		return archSin(x)
-	}
-	return sin(x)
-}
-
-func sin(x float64) float64 {
-	const (
-		PI4A = 7.85398125648498535156e-1  // 0x3fe921fb40000000, Pi/4 split into three parts
-		PI4B = 3.77489470793079817668e-8  // 0x3e64442d00000000,
-		PI4C = 2.69515142907905952645e-15 // 0x3ce8469898cc5170,
-	)
-	// special cases
-	switch {
-	case x == 0 || IsNaN(x):
-		return x // return ±0 || NaN()
-	case IsInf(x, 0):
-		return NaN()
-	}
-
-	// make argument positive but save the sign
-	sign := false
-	if x < 0 {
-		x = -x
-		sign = true
-	}
-
-	var j uint64
-	var y, z float64
-	if x >= reduceThreshold {
-		j, z = trigReduce(x)
-	} else {
-		j = uint64(x * (4 / Pi)) // integer part of x/(Pi/4), as integer for tests on the phase angle
-		y = float64(j)           // integer part of x/(Pi/4), as float
-
-		// map zeros to origin
-		if j&1 == 1 {
-			j++
-			y++
-		}
-		j &= 7                               // octant modulo 2Pi radians (360 degrees)
-		z = ((x - y*PI4A) - y*PI4B) - y*PI4C // Extended precision modular arithmetic
-	}
-	// reflect in x axis
-	if j > 3 {
-		sign = !sign
-		j -= 4
-	}
-	zz := z * z
-	if j == 1 || j == 2 {
-		y = 1.0 - 0.5*zz + zz*zz*((((((_cos[0]*zz)+_cos[1])*zz+_cos[2])*zz+_cos[3])*zz+_cos[4])*zz+_cos[5])
-	} else {
-		y = z + z*zz*((((((_sin[0]*zz)+_sin[1])*zz+_sin[2])*zz+_sin[3])*zz+_sin[4])*zz+_sin[5])
-	}
-	if sign {
-		y = -y
-	}
-	return y
-}
diff --git a/contrib/go/_std_1.18/src/math/sincos.go b/contrib/go/_std_1.18/src/math/sincos.go
deleted file mode 100644
index 5c5726f689..0000000000
--- a/contrib/go/_std_1.18/src/math/sincos.go
+++ /dev/null
@@ -1,72 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-// Coefficients _sin[] and _cos[] are found in pkg/math/sin.go.
-
-// Sincos returns Sin(x), Cos(x).
-//
-// Special cases are:
-//	Sincos(±0) = ±0, 1
-//	Sincos(±Inf) = NaN, NaN
-//	Sincos(NaN) = NaN, NaN
-func Sincos(x float64) (sin, cos float64) {
-	const (
-		PI4A = 7.85398125648498535156e-1  // 0x3fe921fb40000000, Pi/4 split into three parts
-		PI4B = 3.77489470793079817668e-8  // 0x3e64442d00000000,
-		PI4C = 2.69515142907905952645e-15 // 0x3ce8469898cc5170,
-	)
-	// special cases
-	switch {
-	case x == 0:
-		return x, 1 // return ±0.0, 1.0
-	case IsNaN(x) || IsInf(x, 0):
-		return NaN(), NaN()
-	}
-
-	// make argument positive
-	sinSign, cosSign := false, false
-	if x < 0 {
-		x = -x
-		sinSign = true
-	}
-
-	var j uint64
-	var y, z float64
-	if x >= reduceThreshold {
-		j, z = trigReduce(x)
-	} else {
-		j = uint64(x * (4 / Pi)) // integer part of x/(Pi/4), as integer for tests on the phase angle
-		y = float64(j)           // integer part of x/(Pi/4), as float
-
-		if j&1 == 1 { // map zeros to origin
-			j++
-			y++
-		}
-		j &= 7                               // octant modulo 2Pi radians (360 degrees)
-		z = ((x - y*PI4A) - y*PI4B) - y*PI4C // Extended precision modular arithmetic
-	}
-	if j > 3 { // reflect in x axis
-		j -= 4
-		sinSign, cosSign = !sinSign, !cosSign
-	}
-	if j > 1 {
-		cosSign = !cosSign
-	}
-
-	zz := z * z
-	cos = 1.0 - 0.5*zz + zz*zz*((((((_cos[0]*zz)+_cos[1])*zz+_cos[2])*zz+_cos[3])*zz+_cos[4])*zz+_cos[5])
-	sin = z + z*zz*((((((_sin[0]*zz)+_sin[1])*zz+_sin[2])*zz+_sin[3])*zz+_sin[4])*zz+_sin[5])
-	if j == 1 || j == 2 {
-		sin, cos = cos, sin
-	}
-	if cosSign {
-		cos = -cos
-	}
-	if sinSign {
-		sin = -sin
-	}
-	return
-}
diff --git a/contrib/go/_std_1.18/src/math/sinh.go b/contrib/go/_std_1.18/src/math/sinh.go
deleted file mode 100644
index 9fe9b4e17a..0000000000
--- a/contrib/go/_std_1.18/src/math/sinh.go
+++ /dev/null
@@ -1,91 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-/*
-	Floating-point hyperbolic sine and cosine.
-
-	The exponential func is called for arguments
-	greater in magnitude than 0.5.
-
-	A series is used for arguments smaller in magnitude than 0.5.
-
-	Cosh(x) is computed from the exponential func for
-	all arguments.
-*/
-
-// Sinh returns the hyperbolic sine of x.
-//
-// Special cases are:
-//	Sinh(±0) = ±0
-//	Sinh(±Inf) = ±Inf
-//	Sinh(NaN) = NaN
-func Sinh(x float64) float64 {
-	if haveArchSinh {
-		return archSinh(x)
-	}
-	return sinh(x)
-}
-
-func sinh(x float64) float64 {
-	// The coefficients are #2029 from Hart & Cheney. (20.36D)
-	const (
-		P0 = -0.6307673640497716991184787251e+6
-		P1 = -0.8991272022039509355398013511e+5
-		P2 = -0.2894211355989563807284660366e+4
-		P3 = -0.2630563213397497062819489e+2
-		Q0 = -0.6307673640497716991212077277e+6
-		Q1 = 0.1521517378790019070696485176e+5
-		Q2 = -0.173678953558233699533450911e+3
-	)
-
-	sign := false
-	if x < 0 {
-		x = -x
-		sign = true
-	}
-
-	var temp float64
-	switch {
-	case x > 21:
-		temp = Exp(x) * 0.5
-
-	case x > 0.5:
-		ex := Exp(x)
-		temp = (ex - 1/ex) * 0.5
-
-	default:
-		sq := x * x
-		temp = (((P3*sq+P2)*sq+P1)*sq + P0) * x
-		temp = temp / (((sq+Q2)*sq+Q1)*sq + Q0)
-	}
-
-	if sign {
-		temp = -temp
-	}
-	return temp
-}
-
-// Cosh returns the hyperbolic cosine of x.
-//
-// Special cases are:
-//	Cosh(±0) = 1
-//	Cosh(±Inf) = +Inf
-//	Cosh(NaN) = NaN
-func Cosh(x float64) float64 {
-	if haveArchCosh {
-		return archCosh(x)
-	}
-	return cosh(x)
-}
-
-func cosh(x float64) float64 {
-	x = Abs(x)
-	if x > 21 {
-		return Exp(x) * 0.5
-	}
-	ex := Exp(x)
-	return (ex + 1/ex) * 0.5
-}
diff --git a/contrib/go/_std_1.18/src/math/sqrt.go b/contrib/go/_std_1.18/src/math/sqrt.go
deleted file mode 100644
index 903d57d5e0..0000000000
--- a/contrib/go/_std_1.18/src/math/sqrt.go
+++ /dev/null
@@ -1,149 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-// The original C code and the long comment below are
-// from FreeBSD's /usr/src/lib/msun/src/e_sqrt.c and
-// came with this notice. The go code is a simplified
-// version of the original C.
-//
-// ====================================================
-// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
-//
-// Developed at SunPro, a Sun Microsystems, Inc. business.
-// Permission to use, copy, modify, and distribute this
-// software is freely granted, provided that this notice
-// is preserved.
-// ====================================================
-//
-// __ieee754_sqrt(x)
-// Return correctly rounded sqrt.
-//           -----------------------------------------
-//           | Use the hardware sqrt if you have one |
-//           -----------------------------------------
-// Method:
-//   Bit by bit method using integer arithmetic. (Slow, but portable)
-//   1. Normalization
-//      Scale x to y in [1,4) with even powers of 2:
-//      find an integer k such that  1 <= (y=x*2**(2k)) < 4, then
-//              sqrt(x) = 2**k * sqrt(y)
-//   2. Bit by bit computation
-//      Let q  = sqrt(y) truncated to i bit after binary point (q = 1),
-//           i                                                   0
-//                                     i+1         2
-//          s  = 2*q , and      y  =  2   * ( y - q  ).          (1)
-//           i      i            i                 i
-//
-//      To compute q    from q , one checks whether
-//                  i+1       i
-//
-//                            -(i+1) 2
-//                      (q + 2      )  <= y.                     (2)
-//                        i
-//                                                            -(i+1)
-//      If (2) is false, then q   = q ; otherwise q   = q  + 2      .
-//                             i+1   i             i+1   i
-//
-//      With some algebraic manipulation, it is not difficult to see
-//      that (2) is equivalent to
-//                             -(i+1)
-//                      s  +  2       <= y                       (3)
-//                       i                i
-//
-//      The advantage of (3) is that s  and y  can be computed by
-//                                    i      i
-//      the following recurrence formula:
-//          if (3) is false
-//
-//          s     =  s  ,       y    = y   ;                     (4)
-//           i+1      i          i+1    i
-//
-//      otherwise,
-//                         -i                      -(i+1)
-//          s     =  s  + 2  ,  y    = y  -  s  - 2              (5)
-//           i+1      i          i+1    i     i
-//
-//      One may easily use induction to prove (4) and (5).
-//      Note. Since the left hand side of (3) contain only i+2 bits,
-//            it is not necessary to do a full (53-bit) comparison
-//            in (3).
-//   3. Final rounding
-//      After generating the 53 bits result, we compute one more bit.
-//      Together with the remainder, we can decide whether the
-//      result is exact, bigger than 1/2ulp, or less than 1/2ulp
-//      (it will never equal to 1/2ulp).
-//      The rounding mode can be detected by checking whether
-//      huge + tiny is equal to huge, and whether huge - tiny is
-//      equal to huge for some floating point number "huge" and "tiny".
-//
-//
-// Notes:  Rounding mode detection omitted. The constants "mask", "shift",
-// and "bias" are found in src/math/bits.go
-
-// Sqrt returns the square root of x.
-//
-// Special cases are:
-//	Sqrt(+Inf) = +Inf
-//	Sqrt(±0) = ±0
-//	Sqrt(x < 0) = NaN
-//	Sqrt(NaN) = NaN
-func Sqrt(x float64) float64 {
-	if haveArchSqrt {
-		return archSqrt(x)
-	}
-	return sqrt(x)
-}
-
-// Note: Sqrt is implemented in assembly on some systems.
-// Others have assembly stubs that jump to func sqrt below.
-// On systems where Sqrt is a single instruction, the compiler
-// may turn a direct call into a direct use of that instruction instead.
-
-func sqrt(x float64) float64 {
-	// special cases
-	switch {
-	case x == 0 || IsNaN(x) || IsInf(x, 1):
-		return x
-	case x < 0:
-		return NaN()
-	}
-	ix := Float64bits(x)
-	// normalize x
-	exp := int((ix >> shift) & mask)
-	if exp == 0 { // subnormal x
-		for ix&(1<<shift) == 0 {
-			ix <<= 1
-			exp--
-		}
-		exp++
-	}
-	exp -= bias // unbias exponent
-	ix &^= mask << shift
-	ix |= 1 << shift
-	if exp&1 == 1 { // odd exp, double x to make it even
-		ix <<= 1
-	}
-	exp >>= 1 // exp = exp/2, exponent of square root
-	// generate sqrt(x) bit by bit
-	ix <<= 1
-	var q, s uint64               // q = sqrt(x)
-	r := uint64(1 << (shift + 1)) // r = moving bit from MSB to LSB
-	for r != 0 {
-		t := s + r
-		if t <= ix {
-			s = t + r
-			ix -= t
-			q += r
-		}
-		ix <<= 1
-		r >>= 1
-	}
-	// final rounding
-	if ix != 0 { // remainder, result not exact
-		q += q & 1 // round according to extra bit
-	}
-	ix = q>>1 + uint64(exp-1+bias)<<shift // significand + biased exponent
-	return Float64frombits(ix)
-}
diff --git a/contrib/go/_std_1.18/src/math/tan.go b/contrib/go/_std_1.18/src/math/tan.go
deleted file mode 100644
index a25417f527..0000000000
--- a/contrib/go/_std_1.18/src/math/tan.go
+++ /dev/null
@@ -1,139 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-/*
-	Floating-point tangent.
-*/
-
-// The original C code, the long comment, and the constants
-// below were from http://netlib.sandia.gov/cephes/cmath/sin.c,
-// available from http://www.netlib.org/cephes/cmath.tgz.
-// The go code is a simplified version of the original C.
-//
-//      tan.c
-//
-//      Circular tangent
-//
-// SYNOPSIS:
-//
-// double x, y, tan();
-// y = tan( x );
-//
-// DESCRIPTION:
-//
-// Returns the circular tangent of the radian argument x.
-//
-// Range reduction is modulo pi/4.  A rational function
-//       x + x**3 P(x**2)/Q(x**2)
-// is employed in the basic interval [0, pi/4].
-//
-// ACCURACY:
-//                      Relative error:
-// arithmetic   domain     # trials      peak         rms
-//    DEC      +-1.07e9      44000      4.1e-17     1.0e-17
-//    IEEE     +-1.07e9      30000      2.9e-16     8.1e-17
-//
-// Partial loss of accuracy begins to occur at x = 2**30 = 1.074e9.  The loss
-// is not gradual, but jumps suddenly to about 1 part in 10e7.  Results may
-// be meaningless for x > 2**49 = 5.6e14.
-// [Accuracy loss statement from sin.go comments.]
-//
-// Cephes Math Library Release 2.8:  June, 2000
-// Copyright 1984, 1987, 1989, 1992, 2000 by Stephen L. Moshier
-//
-// The readme file at http://netlib.sandia.gov/cephes/ says:
-//    Some software in this archive may be from the book _Methods and
-// Programs for Mathematical Functions_ (Prentice-Hall or Simon & Schuster
-// International, 1989) or from the Cephes Mathematical Library, a
-// commercial product. In either event, it is copyrighted by the author.
-// What you see here may be used freely but it comes with no support or
-// guarantee.
-//
-//   The two known misprints in the book are repaired here in the
-// source listings for the gamma function and the incomplete beta
-// integral.
-//
-//   Stephen L. Moshier
-//   moshier@na-net.ornl.gov
-
-// tan coefficients
-var _tanP = [...]float64{
-	-1.30936939181383777646e4, // 0xc0c992d8d24f3f38
-	1.15351664838587416140e6,  // 0x413199eca5fc9ddd
-	-1.79565251976484877988e7, // 0xc1711fead3299176
-}
-var _tanQ = [...]float64{
-	1.00000000000000000000e0,
-	1.36812963470692954678e4,  //0x40cab8a5eeb36572
-	-1.32089234440210967447e6, //0xc13427bc582abc96
-	2.50083801823357915839e7,  //0x4177d98fc2ead8ef
-	-5.38695755929454629881e7, //0xc189afe03cbe5a31
-}
-
-// Tan returns the tangent of the radian argument x.
-//
-// Special cases are:
-//	Tan(±0) = ±0
-//	Tan(±Inf) = NaN
-//	Tan(NaN) = NaN
-func Tan(x float64) float64 {
-	if haveArchTan {
-		return archTan(x)
-	}
-	return tan(x)
-}
-
-func tan(x float64) float64 {
-	const (
-		PI4A = 7.85398125648498535156e-1  // 0x3fe921fb40000000, Pi/4 split into three parts
-		PI4B = 3.77489470793079817668e-8  // 0x3e64442d00000000,
-		PI4C = 2.69515142907905952645e-15 // 0x3ce8469898cc5170,
-	)
-	// special cases
-	switch {
-	case x == 0 || IsNaN(x):
-		return x // return ±0 || NaN()
-	case IsInf(x, 0):
-		return NaN()
-	}
-
-	// make argument positive but save the sign
-	sign := false
-	if x < 0 {
-		x = -x
-		sign = true
-	}
-	var j uint64
-	var y, z float64
-	if x >= reduceThreshold {
-		j, z = trigReduce(x)
-	} else {
-		j = uint64(x * (4 / Pi)) // integer part of x/(Pi/4), as integer for tests on the phase angle
-		y = float64(j)           // integer part of x/(Pi/4), as float
-
-		/* map zeros and singularities to origin */
-		if j&1 == 1 {
-			j++
-			y++
-		}
-
-		z = ((x - y*PI4A) - y*PI4B) - y*PI4C
-	}
-	zz := z * z
-
-	if zz > 1e-14 {
-		y = z + z*(zz*(((_tanP[0]*zz)+_tanP[1])*zz+_tanP[2])/((((zz+_tanQ[1])*zz+_tanQ[2])*zz+_tanQ[3])*zz+_tanQ[4]))
-	} else {
-		y = z
-	}
-	if j&2 == 2 {
-		y = -1 / y
-	}
-	if sign {
-		y = -y
-	}
-	return y
-}
diff --git a/contrib/go/_std_1.18/src/math/tanh.go b/contrib/go/_std_1.18/src/math/tanh.go
deleted file mode 100644
index a825678424..0000000000
--- a/contrib/go/_std_1.18/src/math/tanh.go
+++ /dev/null
@@ -1,104 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-// The original C code, the long comment, and the constants
-// below were from http://netlib.sandia.gov/cephes/cmath/sin.c,
-// available from http://www.netlib.org/cephes/cmath.tgz.
-// The go code is a simplified version of the original C.
-//      tanh.c
-//
-//      Hyperbolic tangent
-//
-// SYNOPSIS:
-//
-// double x, y, tanh();
-//
-// y = tanh( x );
-//
-// DESCRIPTION:
-//
-// Returns hyperbolic tangent of argument in the range MINLOG to MAXLOG.
-//      MAXLOG = 8.8029691931113054295988e+01 = log(2**127)
-//      MINLOG = -8.872283911167299960540e+01 = log(2**-128)
-//
-// A rational function is used for |x| < 0.625.  The form
-// x + x**3 P(x)/Q(x) of Cody & Waite is employed.
-// Otherwise,
-//      tanh(x) = sinh(x)/cosh(x) = 1  -  2/(exp(2x) + 1).
-//
-// ACCURACY:
-//
-//                      Relative error:
-// arithmetic   domain     # trials      peak         rms
-//    IEEE      -2,2        30000       2.5e-16     5.8e-17
-//
-// Cephes Math Library Release 2.8:  June, 2000
-// Copyright 1984, 1987, 1989, 1992, 2000 by Stephen L. Moshier
-//
-// The readme file at http://netlib.sandia.gov/cephes/ says:
-//    Some software in this archive may be from the book _Methods and
-// Programs for Mathematical Functions_ (Prentice-Hall or Simon & Schuster
-// International, 1989) or from the Cephes Mathematical Library, a
-// commercial product. In either event, it is copyrighted by the author.
-// What you see here may be used freely but it comes with no support or
-// guarantee.
-//
-//   The two known misprints in the book are repaired here in the
-// source listings for the gamma function and the incomplete beta
-// integral.
-//
-//   Stephen L. Moshier
-//   moshier@na-net.ornl.gov
-//
-
-var tanhP = [...]float64{
-	-9.64399179425052238628e-1,
-	-9.92877231001918586564e1,
-	-1.61468768441708447952e3,
-}
-var tanhQ = [...]float64{
-	1.12811678491632931402e2,
-	2.23548839060100448583e3,
-	4.84406305325125486048e3,
-}
-
-// Tanh returns the hyperbolic tangent of x.
-//
-// Special cases are:
-//	Tanh(±0) = ±0
-//	Tanh(±Inf) = ±1
-//	Tanh(NaN) = NaN
-func Tanh(x float64) float64 {
-	if haveArchTanh {
-		return archTanh(x)
-	}
-	return tanh(x)
-}
-
-func tanh(x float64) float64 {
-	const MAXLOG = 8.8029691931113054295988e+01 // log(2**127)
-	z := Abs(x)
-	switch {
-	case z > 0.5*MAXLOG:
-		if x < 0 {
-			return -1
-		}
-		return 1
-	case z >= 0.625:
-		s := Exp(2 * z)
-		z = 1 - 2/(s+1)
-		if x < 0 {
-			z = -z
-		}
-	default:
-		if x == 0 {
-			return x
-		}
-		s := x * x
-		z = x + x*s*((tanhP[0]*s+tanhP[1])*s+tanhP[2])/(((s+tanhQ[0])*s+tanhQ[1])*s+tanhQ[2])
-	}
-	return z
-}
diff --git a/contrib/go/_std_1.18/src/math/trig_reduce.go b/contrib/go/_std_1.18/src/math/trig_reduce.go
deleted file mode 100644
index 5cdf4fa013..0000000000
--- a/contrib/go/_std_1.18/src/math/trig_reduce.go
+++ /dev/null
@@ -1,100 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package math
-
-import (
-	"math/bits"
-)
-
-// reduceThreshold is the maximum value of x where the reduction using Pi/4
-// in 3 float64 parts still gives accurate results. This threshold
-// is set by y*C being representable as a float64 without error
-// where y is given by y = floor(x * (4 / Pi)) and C is the leading partial
-// terms of 4/Pi. Since the leading terms (PI4A and PI4B in sin.go) have 30
-// and 32 trailing zero bits, y should have less than 30 significant bits.
-//	y < 1<<30  -> floor(x*4/Pi) < 1<<30 -> x < (1<<30 - 1) * Pi/4
-// So, conservatively we can take x < 1<<29.
-// Above this threshold Payne-Hanek range reduction must be used.
-const reduceThreshold = 1 << 29
-
-// trigReduce implements Payne-Hanek range reduction by Pi/4
-// for x > 0. It returns the integer part mod 8 (j) and
-// the fractional part (z) of x / (Pi/4).
-// The implementation is based on:
-// "ARGUMENT REDUCTION FOR HUGE ARGUMENTS: Good to the Last Bit"
-// K. C. Ng et al, March 24, 1992
-// The simulated multi-precision calculation of x*B uses 64-bit integer arithmetic.
-func trigReduce(x float64) (j uint64, z float64) {
-	const PI4 = Pi / 4
-	if x < PI4 {
-		return 0, x
-	}
-	// Extract out the integer and exponent such that,
-	// x = ix * 2 ** exp.
-	ix := Float64bits(x)
-	exp := int(ix>>shift&mask) - bias - shift
-	ix &^= mask << shift
-	ix |= 1 << shift
-	// Use the exponent to extract the 3 appropriate uint64 digits from mPi4,
-	// B ~ (z0, z1, z2), such that the product leading digit has the exponent -61.
-	// Note, exp >= -53 since x >= PI4 and exp < 971 for maximum float64.
-	digit, bitshift := uint(exp+61)/64, uint(exp+61)%64
-	z0 := (mPi4[digit] << bitshift) | (mPi4[digit+1] >> (64 - bitshift))
-	z1 := (mPi4[digit+1] << bitshift) | (mPi4[digit+2] >> (64 - bitshift))
-	z2 := (mPi4[digit+2] << bitshift) | (mPi4[digit+3] >> (64 - bitshift))
-	// Multiply mantissa by the digits and extract the upper two digits (hi, lo).
-	z2hi, _ := bits.Mul64(z2, ix)
-	z1hi, z1lo := bits.Mul64(z1, ix)
-	z0lo := z0 * ix
-	lo, c := bits.Add64(z1lo, z2hi, 0)
-	hi, _ := bits.Add64(z0lo, z1hi, c)
-	// The top 3 bits are j.
-	j = hi >> 61
-	// Extract the fraction and find its magnitude.
-	hi = hi<<3 | lo>>61
-	lz := uint(bits.LeadingZeros64(hi))
-	e := uint64(bias - (lz + 1))
-	// Clear implicit mantissa bit and shift into place.
-	hi = (hi << (lz + 1)) | (lo >> (64 - (lz + 1)))
-	hi >>= 64 - shift
-	// Include the exponent and convert to a float.
-	hi |= e << shift
-	z = Float64frombits(hi)
-	// Map zeros to origin.
-	if j&1 == 1 {
-		j++
-		j &= 7
-		z--
-	}
-	// Multiply the fractional part by pi/4.
-	return j, z * PI4
-}
-
-// mPi4 is the binary digits of 4/pi as a uint64 array,
-// that is, 4/pi = Sum mPi4[i]*2^(-64*i)
-// 19 64-bit digits and the leading one bit give 1217 bits
-// of precision to handle the largest possible float64 exponent.
-var mPi4 = [...]uint64{
-	0x0000000000000001,
-	0x45f306dc9c882a53,
-	0xf84eafa3ea69bb81,
-	0xb6c52b3278872083,
-	0xfca2c757bd778ac3,
-	0x6e48dc74849ba5c0,
-	0x0c925dd413a32439,
-	0xfc3bd63962534e7d,
-	0xd1046bea5d768909,
-	0xd338e04d68befc82,
-	0x7323ac7306a673e9,
-	0x3908bf177bf25076,
-	0x3ff12fffbc0b301f,
-	0xde5e2316b414da3e,
-	0xda6cfd9e4f96136e,
-	0x9e8c7ecd3cbfd45a,
-	0xea4f758fd7cbe2f6,
-	0x7a0e73ef14a525d4,
-	0xd7f6bf623f1aba10,
-	0xac06608df8f6d757,
-}
diff --git a/contrib/go/_std_1.18/src/mime/multipart/multipart.go b/contrib/go/_std_1.18/src/mime/multipart/multipart.go
deleted file mode 100644
index 81bf722d4e..0000000000
--- a/contrib/go/_std_1.18/src/mime/multipart/multipart.go
+++ /dev/null
@@ -1,429 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-//
-
-/*
-Package multipart implements MIME multipart parsing, as defined in RFC
-2046.
-
-The implementation is sufficient for HTTP (RFC 2388) and the multipart
-bodies generated by popular browsers.
-*/
-package multipart
-
-import (
-	"bufio"
-	"bytes"
-	"fmt"
-	"io"
-	"mime"
-	"mime/quotedprintable"
-	"net/textproto"
-	"path/filepath"
-	"strings"
-)
-
-var emptyParams = make(map[string]string)
-
-// This constant needs to be at least 76 for this package to work correctly.
-// This is because \r\n--separator_of_len_70- would fill the buffer and it
-// wouldn't be safe to consume a single byte from it.
-const peekBufferSize = 4096
-
-// A Part represents a single part in a multipart body.
-type Part struct {
-	// The headers of the body, if any, with the keys canonicalized
-	// in the same fashion that the Go http.Request headers are.
-	// For example, "foo-bar" changes case to "Foo-Bar"
-	Header textproto.MIMEHeader
-
-	mr *Reader
-
-	disposition       string
-	dispositionParams map[string]string
-
-	// r is either a reader directly reading from mr, or it's a
-	// wrapper around such a reader, decoding the
-	// Content-Transfer-Encoding
-	r io.Reader
-
-	n       int   // known data bytes waiting in mr.bufReader
-	total   int64 // total data bytes read already
-	err     error // error to return when n == 0
-	readErr error // read error observed from mr.bufReader
-}
-
-// FormName returns the name parameter if p has a Content-Disposition
-// of type "form-data".  Otherwise it returns the empty string.
-func (p *Part) FormName() string {
-	// See https://tools.ietf.org/html/rfc2183 section 2 for EBNF
-	// of Content-Disposition value format.
-	if p.dispositionParams == nil {
-		p.parseContentDisposition()
-	}
-	if p.disposition != "form-data" {
-		return ""
-	}
-	return p.dispositionParams["name"]
-}
-
-// FileName returns the filename parameter of the Part's Content-Disposition
-// header. If not empty, the filename is passed through filepath.Base (which is
-// platform dependent) before being returned.
-func (p *Part) FileName() string {
-	if p.dispositionParams == nil {
-		p.parseContentDisposition()
-	}
-	filename := p.dispositionParams["filename"]
-	if filename == "" {
-		return ""
-	}
-	// RFC 7578, Section 4.2 requires that if a filename is provided, the
-	// directory path information must not be used.
-	return filepath.Base(filename)
-}
-
-func (p *Part) parseContentDisposition() {
-	v := p.Header.Get("Content-Disposition")
-	var err error
-	p.disposition, p.dispositionParams, err = mime.ParseMediaType(v)
-	if err != nil {
-		p.dispositionParams = emptyParams
-	}
-}
-
-// NewReader creates a new multipart Reader reading from r using the
-// given MIME boundary.
-//
-// The boundary is usually obtained from the "boundary" parameter of
-// the message's "Content-Type" header. Use mime.ParseMediaType to
-// parse such headers.
-func NewReader(r io.Reader, boundary string) *Reader {
-	b := []byte("\r\n--" + boundary + "--")
-	return &Reader{
-		bufReader:        bufio.NewReaderSize(&stickyErrorReader{r: r}, peekBufferSize),
-		nl:               b[:2],
-		nlDashBoundary:   b[:len(b)-2],
-		dashBoundaryDash: b[2:],
-		dashBoundary:     b[2 : len(b)-2],
-	}
-}
-
-// stickyErrorReader is an io.Reader which never calls Read on its
-// underlying Reader once an error has been seen. (the io.Reader
-// interface's contract promises nothing about the return values of
-// Read calls after an error, yet this package does do multiple Reads
-// after error)
-type stickyErrorReader struct {
-	r   io.Reader
-	err error
-}
-
-func (r *stickyErrorReader) Read(p []byte) (n int, _ error) {
-	if r.err != nil {
-		return 0, r.err
-	}
-	n, r.err = r.r.Read(p)
-	return n, r.err
-}
-
-func newPart(mr *Reader, rawPart bool) (*Part, error) {
-	bp := &Part{
-		Header: make(map[string][]string),
-		mr:     mr,
-	}
-	if err := bp.populateHeaders(); err != nil {
-		return nil, err
-	}
-	bp.r = partReader{bp}
-
-	// rawPart is used to switch between Part.NextPart and Part.NextRawPart.
-	if !rawPart {
-		const cte = "Content-Transfer-Encoding"
-		if strings.EqualFold(bp.Header.Get(cte), "quoted-printable") {
-			bp.Header.Del(cte)
-			bp.r = quotedprintable.NewReader(bp.r)
-		}
-	}
-	return bp, nil
-}
-
-func (bp *Part) populateHeaders() error {
-	r := textproto.NewReader(bp.mr.bufReader)
-	header, err := r.ReadMIMEHeader()
-	if err == nil {
-		bp.Header = header
-	}
-	return err
-}
-
-// Read reads the body of a part, after its headers and before the
-// next part (if any) begins.
-func (p *Part) Read(d []byte) (n int, err error) {
-	return p.r.Read(d)
-}
-
-// partReader implements io.Reader by reading raw bytes directly from the
-// wrapped *Part, without doing any Transfer-Encoding decoding.
-type partReader struct {
-	p *Part
-}
-
-func (pr partReader) Read(d []byte) (int, error) {
-	p := pr.p
-	br := p.mr.bufReader
-
-	// Read into buffer until we identify some data to return,
-	// or we find a reason to stop (boundary or read error).
-	for p.n == 0 && p.err == nil {
-		peek, _ := br.Peek(br.Buffered())
-		p.n, p.err = scanUntilBoundary(peek, p.mr.dashBoundary, p.mr.nlDashBoundary, p.total, p.readErr)
-		if p.n == 0 && p.err == nil {
-			// Force buffered I/O to read more into buffer.
-			_, p.readErr = br.Peek(len(peek) + 1)
-			if p.readErr == io.EOF {
-				p.readErr = io.ErrUnexpectedEOF
-			}
-		}
-	}
-
-	// Read out from "data to return" part of buffer.
-	if p.n == 0 {
-		return 0, p.err
-	}
-	n := len(d)
-	if n > p.n {
-		n = p.n
-	}
-	n, _ = br.Read(d[:n])
-	p.total += int64(n)
-	p.n -= n
-	if p.n == 0 {
-		return n, p.err
-	}
-	return n, nil
-}
-
-// scanUntilBoundary scans buf to identify how much of it can be safely
-// returned as part of the Part body.
-// dashBoundary is "--boundary".
-// nlDashBoundary is "\r\n--boundary" or "\n--boundary", depending on what mode we are in.
-// The comments below (and the name) assume "\n--boundary", but either is accepted.
-// total is the number of bytes read out so far. If total == 0, then a leading "--boundary" is recognized.
-// readErr is the read error, if any, that followed reading the bytes in buf.
-// scanUntilBoundary returns the number of data bytes from buf that can be
-// returned as part of the Part body and also the error to return (if any)
-// once those data bytes are done.
-func scanUntilBoundary(buf, dashBoundary, nlDashBoundary []byte, total int64, readErr error) (int, error) {
-	if total == 0 {
-		// At beginning of body, allow dashBoundary.
-		if bytes.HasPrefix(buf, dashBoundary) {
-			switch matchAfterPrefix(buf, dashBoundary, readErr) {
-			case -1:
-				return len(dashBoundary), nil
-			case 0:
-				return 0, nil
-			case +1:
-				return 0, io.EOF
-			}
-		}
-		if bytes.HasPrefix(dashBoundary, buf) {
-			return 0, readErr
-		}
-	}
-
-	// Search for "\n--boundary".
-	if i := bytes.Index(buf, nlDashBoundary); i >= 0 {
-		switch matchAfterPrefix(buf[i:], nlDashBoundary, readErr) {
-		case -1:
-			return i + len(nlDashBoundary), nil
-		case 0:
-			return i, nil
-		case +1:
-			return i, io.EOF
-		}
-	}
-	if bytes.HasPrefix(nlDashBoundary, buf) {
-		return 0, readErr
-	}
-
-	// Otherwise, anything up to the final \n is not part of the boundary
-	// and so must be part of the body.
-	// Also if the section from the final \n onward is not a prefix of the boundary,
-	// it too must be part of the body.
-	i := bytes.LastIndexByte(buf, nlDashBoundary[0])
-	if i >= 0 && bytes.HasPrefix(nlDashBoundary, buf[i:]) {
-		return i, nil
-	}
-	return len(buf), readErr
-}
-
-// matchAfterPrefix checks whether buf should be considered to match the boundary.
-// The prefix is "--boundary" or "\r\n--boundary" or "\n--boundary",
-// and the caller has verified already that bytes.HasPrefix(buf, prefix) is true.
-//
-// matchAfterPrefix returns +1 if the buffer does match the boundary,
-// meaning the prefix is followed by a dash, space, tab, cr, nl, or end of input.
-// It returns -1 if the buffer definitely does NOT match the boundary,
-// meaning the prefix is followed by some other character.
-// For example, "--foobar" does not match "--foo".
-// It returns 0 more input needs to be read to make the decision,
-// meaning that len(buf) == len(prefix) and readErr == nil.
-func matchAfterPrefix(buf, prefix []byte, readErr error) int {
-	if len(buf) == len(prefix) {
-		if readErr != nil {
-			return +1
-		}
-		return 0
-	}
-	c := buf[len(prefix)]
-	if c == ' ' || c == '\t' || c == '\r' || c == '\n' || c == '-' {
-		return +1
-	}
-	return -1
-}
-
-func (p *Part) Close() error {
-	io.Copy(io.Discard, p)
-	return nil
-}
-
-// Reader is an iterator over parts in a MIME multipart body.
-// Reader's underlying parser consumes its input as needed. Seeking
-// isn't supported.
-type Reader struct {
-	bufReader *bufio.Reader
-
-	currentPart *Part
-	partsRead   int
-
-	nl               []byte // "\r\n" or "\n" (set after seeing first boundary line)
-	nlDashBoundary   []byte // nl + "--boundary"
-	dashBoundaryDash []byte // "--boundary--"
-	dashBoundary     []byte // "--boundary"
-}
-
-// NextPart returns the next part in the multipart or an error.
-// When there are no more parts, the error io.EOF is returned.
-//
-// As a special case, if the "Content-Transfer-Encoding" header
-// has a value of "quoted-printable", that header is instead
-// hidden and the body is transparently decoded during Read calls.
-func (r *Reader) NextPart() (*Part, error) {
-	return r.nextPart(false)
-}
-
-// NextRawPart returns the next part in the multipart or an error.
-// When there are no more parts, the error io.EOF is returned.
-//
-// Unlike NextPart, it does not have special handling for
-// "Content-Transfer-Encoding: quoted-printable".
-func (r *Reader) NextRawPart() (*Part, error) {
-	return r.nextPart(true)
-}
-
-func (r *Reader) nextPart(rawPart bool) (*Part, error) {
-	if r.currentPart != nil {
-		r.currentPart.Close()
-	}
-	if string(r.dashBoundary) == "--" {
-		return nil, fmt.Errorf("multipart: boundary is empty")
-	}
-	expectNewPart := false
-	for {
-		line, err := r.bufReader.ReadSlice('\n')
-
-		if err == io.EOF && r.isFinalBoundary(line) {
-			// If the buffer ends in "--boundary--" without the
-			// trailing "\r\n", ReadSlice will return an error
-			// (since it's missing the '\n'), but this is a valid
-			// multipart EOF so we need to return io.EOF instead of
-			// a fmt-wrapped one.
-			return nil, io.EOF
-		}
-		if err != nil {
-			return nil, fmt.Errorf("multipart: NextPart: %v", err)
-		}
-
-		if r.isBoundaryDelimiterLine(line) {
-			r.partsRead++
-			bp, err := newPart(r, rawPart)
-			if err != nil {
-				return nil, err
-			}
-			r.currentPart = bp
-			return bp, nil
-		}
-
-		if r.isFinalBoundary(line) {
-			// Expected EOF
-			return nil, io.EOF
-		}
-
-		if expectNewPart {
-			return nil, fmt.Errorf("multipart: expecting a new Part; got line %q", string(line))
-		}
-
-		if r.partsRead == 0 {
-			// skip line
-			continue
-		}
-
-		// Consume the "\n" or "\r\n" separator between the
-		// body of the previous part and the boundary line we
-		// now expect will follow. (either a new part or the
-		// end boundary)
-		if bytes.Equal(line, r.nl) {
-			expectNewPart = true
-			continue
-		}
-
-		return nil, fmt.Errorf("multipart: unexpected line in Next(): %q", line)
-	}
-}
-
-// isFinalBoundary reports whether line is the final boundary line
-// indicating that all parts are over.
-// It matches `^--boundary--[ \t]*(\r\n)?$`
-func (mr *Reader) isFinalBoundary(line []byte) bool {
-	if !bytes.HasPrefix(line, mr.dashBoundaryDash) {
-		return false
-	}
-	rest := line[len(mr.dashBoundaryDash):]
-	rest = skipLWSPChar(rest)
-	return len(rest) == 0 || bytes.Equal(rest, mr.nl)
-}
-
-func (mr *Reader) isBoundaryDelimiterLine(line []byte) (ret bool) {
-	// https://tools.ietf.org/html/rfc2046#section-5.1
-	//   The boundary delimiter line is then defined as a line
-	//   consisting entirely of two hyphen characters ("-",
-	//   decimal value 45) followed by the boundary parameter
-	//   value from the Content-Type header field, optional linear
-	//   whitespace, and a terminating CRLF.
-	if !bytes.HasPrefix(line, mr.dashBoundary) {
-		return false
-	}
-	rest := line[len(mr.dashBoundary):]
-	rest = skipLWSPChar(rest)
-
-	// On the first part, see our lines are ending in \n instead of \r\n
-	// and switch into that mode if so. This is a violation of the spec,
-	// but occurs in practice.
-	if mr.partsRead == 0 && len(rest) == 1 && rest[0] == '\n' {
-		mr.nl = mr.nl[1:]
-		mr.nlDashBoundary = mr.nlDashBoundary[1:]
-	}
-	return bytes.Equal(rest, mr.nl)
-}
-
-// skipLWSPChar returns b with leading spaces and tabs removed.
-// RFC 822 defines:
-//    LWSP-char = SPACE / HTAB
-func skipLWSPChar(b []byte) []byte {
-	for len(b) > 0 && (b[0] == ' ' || b[0] == '\t') {
-		b = b[1:]
-	}
-	return b
-}
diff --git a/contrib/go/_std_1.18/src/mime/type.go b/contrib/go/_std_1.18/src/mime/type.go
deleted file mode 100644
index bdb8bb319a..0000000000
--- a/contrib/go/_std_1.18/src/mime/type.go
+++ /dev/null
@@ -1,202 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package mime implements parts of the MIME spec.
-package mime
-
-import (
-	"fmt"
-	"sort"
-	"strings"
-	"sync"
-)
-
-var (
-	mimeTypes      sync.Map // map[string]string; ".Z" => "application/x-compress"
-	mimeTypesLower sync.Map // map[string]string; ".z" => "application/x-compress"
-
-	// extensions maps from MIME type to list of lowercase file
-	// extensions: "image/jpeg" => [".jpg", ".jpeg"]
-	extensionsMu sync.Mutex // Guards stores (but not loads) on extensions.
-	extensions   sync.Map   // map[string][]string; slice values are append-only.
-)
-
-func clearSyncMap(m *sync.Map) {
-	m.Range(func(k, _ any) bool {
-		m.Delete(k)
-		return true
-	})
-}
-
-// setMimeTypes is used by initMime's non-test path, and by tests.
-func setMimeTypes(lowerExt, mixExt map[string]string) {
-	clearSyncMap(&mimeTypes)
-	clearSyncMap(&mimeTypesLower)
-	clearSyncMap(&extensions)
-
-	for k, v := range lowerExt {
-		mimeTypesLower.Store(k, v)
-	}
-	for k, v := range mixExt {
-		mimeTypes.Store(k, v)
-	}
-
-	extensionsMu.Lock()
-	defer extensionsMu.Unlock()
-	for k, v := range lowerExt {
-		justType, _, err := ParseMediaType(v)
-		if err != nil {
-			panic(err)
-		}
-		var exts []string
-		if ei, ok := extensions.Load(justType); ok {
-			exts = ei.([]string)
-		}
-		extensions.Store(justType, append(exts, k))
-	}
-}
-
-var builtinTypesLower = map[string]string{
-	".avif": "image/avif",
-	".css":  "text/css; charset=utf-8",
-	".gif":  "image/gif",
-	".htm":  "text/html; charset=utf-8",
-	".html": "text/html; charset=utf-8",
-	".jpeg": "image/jpeg",
-	".jpg":  "image/jpeg",
-	".js":   "text/javascript; charset=utf-8",
-	".json": "application/json",
-	".mjs":  "text/javascript; charset=utf-8",
-	".pdf":  "application/pdf",
-	".png":  "image/png",
-	".svg":  "image/svg+xml",
-	".wasm": "application/wasm",
-	".webp": "image/webp",
-	".xml":  "text/xml; charset=utf-8",
-}
-
-var once sync.Once // guards initMime
-
-var testInitMime, osInitMime func()
-
-func initMime() {
-	if fn := testInitMime; fn != nil {
-		fn()
-	} else {
-		setMimeTypes(builtinTypesLower, builtinTypesLower)
-		osInitMime()
-	}
-}
-
-// TypeByExtension returns the MIME type associated with the file extension ext.
-// The extension ext should begin with a leading dot, as in ".html".
-// When ext has no associated type, TypeByExtension returns "".
-//
-// Extensions are looked up first case-sensitively, then case-insensitively.
-//
-// The built-in table is small but on unix it is augmented by the local
-// system's MIME-info database or mime.types file(s) if available under one or
-// more of these names:
-//
-//   /usr/local/share/mime/globs2
-//   /usr/share/mime/globs2
-//   /etc/mime.types
-//   /etc/apache2/mime.types
-//   /etc/apache/mime.types
-//
-// On Windows, MIME types are extracted from the registry.
-//
-// Text types have the charset parameter set to "utf-8" by default.
-func TypeByExtension(ext string) string {
-	once.Do(initMime)
-
-	// Case-sensitive lookup.
-	if v, ok := mimeTypes.Load(ext); ok {
-		return v.(string)
-	}
-
-	// Case-insensitive lookup.
-	// Optimistically assume a short ASCII extension and be
-	// allocation-free in that case.
-	var buf [10]byte
-	lower := buf[:0]
-	const utf8RuneSelf = 0x80 // from utf8 package, but not importing it.
-	for i := 0; i < len(ext); i++ {
-		c := ext[i]
-		if c >= utf8RuneSelf {
-			// Slow path.
-			si, _ := mimeTypesLower.Load(strings.ToLower(ext))
-			s, _ := si.(string)
-			return s
-		}
-		if 'A' <= c && c <= 'Z' {
-			lower = append(lower, c+('a'-'A'))
-		} else {
-			lower = append(lower, c)
-		}
-	}
-	si, _ := mimeTypesLower.Load(string(lower))
-	s, _ := si.(string)
-	return s
-}
-
-// ExtensionsByType returns the extensions known to be associated with the MIME
-// type typ. The returned extensions will each begin with a leading dot, as in
-// ".html". When typ has no associated extensions, ExtensionsByType returns an
-// nil slice.
-func ExtensionsByType(typ string) ([]string, error) {
-	justType, _, err := ParseMediaType(typ)
-	if err != nil {
-		return nil, err
-	}
-
-	once.Do(initMime)
-	s, ok := extensions.Load(justType)
-	if !ok {
-		return nil, nil
-	}
-	ret := append([]string(nil), s.([]string)...)
-	sort.Strings(ret)
-	return ret, nil
-}
-
-// AddExtensionType sets the MIME type associated with
-// the extension ext to typ. The extension should begin with
-// a leading dot, as in ".html".
-func AddExtensionType(ext, typ string) error {
-	if !strings.HasPrefix(ext, ".") {
-		return fmt.Errorf("mime: extension %q missing leading dot", ext)
-	}
-	once.Do(initMime)
-	return setExtensionType(ext, typ)
-}
-
-func setExtensionType(extension, mimeType string) error {
-	justType, param, err := ParseMediaType(mimeType)
-	if err != nil {
-		return err
-	}
-	if strings.HasPrefix(mimeType, "text/") && param["charset"] == "" {
-		param["charset"] = "utf-8"
-		mimeType = FormatMediaType(mimeType, param)
-	}
-	extLower := strings.ToLower(extension)
-
-	mimeTypes.Store(extension, mimeType)
-	mimeTypesLower.Store(extLower, mimeType)
-
-	extensionsMu.Lock()
-	defer extensionsMu.Unlock()
-	var exts []string
-	if ei, ok := extensions.Load(justType); ok {
-		exts = ei.([]string)
-	}
-	for _, v := range exts {
-		if v == extLower {
-			return nil
-		}
-	}
-	extensions.Store(justType, append(exts, extLower))
-	return nil
-}
diff --git a/contrib/go/_std_1.18/src/mime/type_unix.go b/contrib/go/_std_1.18/src/mime/type_unix.go
deleted file mode 100644
index 3abc1fa10e..0000000000
--- a/contrib/go/_std_1.18/src/mime/type_unix.go
+++ /dev/null
@@ -1,114 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris
-
-package mime
-
-import (
-	"bufio"
-	"os"
-	"strings"
-)
-
-func init() {
-	osInitMime = initMimeUnix
-}
-
-// See https://specifications.freedesktop.org/shared-mime-info-spec/shared-mime-info-spec-0.21.html
-// for the FreeDesktop Shared MIME-info Database specification.
-var mimeGlobs = []string{
-	"/usr/local/share/mime/globs2",
-	"/usr/share/mime/globs2",
-}
-
-// Common locations for mime.types files on unix.
-var typeFiles = []string{
-	"/etc/mime.types",
-	"/etc/apache2/mime.types",
-	"/etc/apache/mime.types",
-	"/etc/httpd/conf/mime.types",
-}
-
-func loadMimeGlobsFile(filename string) error {
-	f, err := os.Open(filename)
-	if err != nil {
-		return err
-	}
-	defer f.Close()
-
-	scanner := bufio.NewScanner(f)
-	for scanner.Scan() {
-		// Each line should be of format: weight:mimetype:*.ext
-		fields := strings.Split(scanner.Text(), ":")
-		if len(fields) < 3 || len(fields[0]) < 1 || len(fields[2]) < 2 {
-			continue
-		} else if fields[0][0] == '#' || fields[2][0] != '*' {
-			continue
-		}
-
-		extension := fields[2][1:]
-		if _, ok := mimeTypes.Load(extension); ok {
-			// We've already seen this extension.
-			// The file is in weight order, so we keep
-			// the first entry that we see.
-			continue
-		}
-
-		setExtensionType(extension, fields[1])
-	}
-	if err := scanner.Err(); err != nil {
-		panic(err)
-	}
-	return nil
-}
-
-func loadMimeFile(filename string) {
-	f, err := os.Open(filename)
-	if err != nil {
-		return
-	}
-	defer f.Close()
-
-	scanner := bufio.NewScanner(f)
-	for scanner.Scan() {
-		fields := strings.Fields(scanner.Text())
-		if len(fields) <= 1 || fields[0][0] == '#' {
-			continue
-		}
-		mimeType := fields[0]
-		for _, ext := range fields[1:] {
-			if ext[0] == '#' {
-				break
-			}
-			setExtensionType("."+ext, mimeType)
-		}
-	}
-	if err := scanner.Err(); err != nil {
-		panic(err)
-	}
-}
-
-func initMimeUnix() {
-	for _, filename := range mimeGlobs {
-		if err := loadMimeGlobsFile(filename); err == nil {
-			return // Stop checking more files if mimetype database is found.
-		}
-	}
-
-	// Fallback if no system-generated mimetype database exists.
-	for _, filename := range typeFiles {
-		loadMimeFile(filename)
-	}
-}
-
-func initMimeForTests() map[string]string {
-	mimeGlobs = []string{""}
-	typeFiles = []string{"testdata/test.types"}
-	return map[string]string{
-		".T1":  "application/test",
-		".t2":  "text/test; charset=utf-8",
-		".png": "image/png",
-	}
-}
diff --git a/contrib/go/_std_1.18/src/net/addrselect.go b/contrib/go/_std_1.18/src/net/addrselect.go
deleted file mode 100644
index 29e4ed85ab..0000000000
--- a/contrib/go/_std_1.18/src/net/addrselect.go
+++ /dev/null
@@ -1,390 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
-
-// Minimal RFC 6724 address selection.
-
-package net
-
-import "sort"
-
-func sortByRFC6724(addrs []IPAddr) {
-	if len(addrs) < 2 {
-		return
-	}
-	sortByRFC6724withSrcs(addrs, srcAddrs(addrs))
-}
-
-func sortByRFC6724withSrcs(addrs []IPAddr, srcs []IP) {
-	if len(addrs) != len(srcs) {
-		panic("internal error")
-	}
-	addrAttr := make([]ipAttr, len(addrs))
-	srcAttr := make([]ipAttr, len(srcs))
-	for i, v := range addrs {
-		addrAttr[i] = ipAttrOf(v.IP)
-		srcAttr[i] = ipAttrOf(srcs[i])
-	}
-	sort.Stable(&byRFC6724{
-		addrs:    addrs,
-		addrAttr: addrAttr,
-		srcs:     srcs,
-		srcAttr:  srcAttr,
-	})
-}
-
-// srcsAddrs tries to UDP-connect to each address to see if it has a
-// route. (This doesn't send any packets). The destination port
-// number is irrelevant.
-func srcAddrs(addrs []IPAddr) []IP {
-	srcs := make([]IP, len(addrs))
-	dst := UDPAddr{Port: 9}
-	for i := range addrs {
-		dst.IP = addrs[i].IP
-		dst.Zone = addrs[i].Zone
-		c, err := DialUDP("udp", nil, &dst)
-		if err == nil {
-			if src, ok := c.LocalAddr().(*UDPAddr); ok {
-				srcs[i] = src.IP
-			}
-			c.Close()
-		}
-	}
-	return srcs
-}
-
-type ipAttr struct {
-	Scope      scope
-	Precedence uint8
-	Label      uint8
-}
-
-func ipAttrOf(ip IP) ipAttr {
-	if ip == nil {
-		return ipAttr{}
-	}
-	match := rfc6724policyTable.Classify(ip)
-	return ipAttr{
-		Scope:      classifyScope(ip),
-		Precedence: match.Precedence,
-		Label:      match.Label,
-	}
-}
-
-type byRFC6724 struct {
-	addrs    []IPAddr // addrs to sort
-	addrAttr []ipAttr
-	srcs     []IP // or nil if unreachable
-	srcAttr  []ipAttr
-}
-
-func (s *byRFC6724) Len() int { return len(s.addrs) }
-
-func (s *byRFC6724) Swap(i, j int) {
-	s.addrs[i], s.addrs[j] = s.addrs[j], s.addrs[i]
-	s.srcs[i], s.srcs[j] = s.srcs[j], s.srcs[i]
-	s.addrAttr[i], s.addrAttr[j] = s.addrAttr[j], s.addrAttr[i]
-	s.srcAttr[i], s.srcAttr[j] = s.srcAttr[j], s.srcAttr[i]
-}
-
-// Less reports whether i is a better destination address for this
-// host than j.
-//
-// The algorithm and variable names comes from RFC 6724 section 6.
-func (s *byRFC6724) Less(i, j int) bool {
-	DA := s.addrs[i].IP
-	DB := s.addrs[j].IP
-	SourceDA := s.srcs[i]
-	SourceDB := s.srcs[j]
-	attrDA := &s.addrAttr[i]
-	attrDB := &s.addrAttr[j]
-	attrSourceDA := &s.srcAttr[i]
-	attrSourceDB := &s.srcAttr[j]
-
-	const preferDA = true
-	const preferDB = false
-
-	// Rule 1: Avoid unusable destinations.
-	// If DB is known to be unreachable or if Source(DB) is undefined, then
-	// prefer DA.  Similarly, if DA is known to be unreachable or if
-	// Source(DA) is undefined, then prefer DB.
-	if SourceDA == nil && SourceDB == nil {
-		return false // "equal"
-	}
-	if SourceDB == nil {
-		return preferDA
-	}
-	if SourceDA == nil {
-		return preferDB
-	}
-
-	// Rule 2: Prefer matching scope.
-	// If Scope(DA) = Scope(Source(DA)) and Scope(DB) <> Scope(Source(DB)),
-	// then prefer DA.  Similarly, if Scope(DA) <> Scope(Source(DA)) and
-	// Scope(DB) = Scope(Source(DB)), then prefer DB.
-	if attrDA.Scope == attrSourceDA.Scope && attrDB.Scope != attrSourceDB.Scope {
-		return preferDA
-	}
-	if attrDA.Scope != attrSourceDA.Scope && attrDB.Scope == attrSourceDB.Scope {
-		return preferDB
-	}
-
-	// Rule 3: Avoid deprecated addresses.
-	// If Source(DA) is deprecated and Source(DB) is not, then prefer DB.
-	// Similarly, if Source(DA) is not deprecated and Source(DB) is
-	// deprecated, then prefer DA.
-
-	// TODO(bradfitz): implement? low priority for now.
-
-	// Rule 4: Prefer home addresses.
-	// If Source(DA) is simultaneously a home address and care-of address
-	// and Source(DB) is not, then prefer DA.  Similarly, if Source(DB) is
-	// simultaneously a home address and care-of address and Source(DA) is
-	// not, then prefer DB.
-
-	// TODO(bradfitz): implement? low priority for now.
-
-	// Rule 5: Prefer matching label.
-	// If Label(Source(DA)) = Label(DA) and Label(Source(DB)) <> Label(DB),
-	// then prefer DA.  Similarly, if Label(Source(DA)) <> Label(DA) and
-	// Label(Source(DB)) = Label(DB), then prefer DB.
-	if attrSourceDA.Label == attrDA.Label &&
-		attrSourceDB.Label != attrDB.Label {
-		return preferDA
-	}
-	if attrSourceDA.Label != attrDA.Label &&
-		attrSourceDB.Label == attrDB.Label {
-		return preferDB
-	}
-
-	// Rule 6: Prefer higher precedence.
-	// If Precedence(DA) > Precedence(DB), then prefer DA.  Similarly, if
-	// Precedence(DA) < Precedence(DB), then prefer DB.
-	if attrDA.Precedence > attrDB.Precedence {
-		return preferDA
-	}
-	if attrDA.Precedence < attrDB.Precedence {
-		return preferDB
-	}
-
-	// Rule 7: Prefer native transport.
-	// If DA is reached via an encapsulating transition mechanism (e.g.,
-	// IPv6 in IPv4) and DB is not, then prefer DB.  Similarly, if DB is
-	// reached via encapsulation and DA is not, then prefer DA.
-
-	// TODO(bradfitz): implement? low priority for now.
-
-	// Rule 8: Prefer smaller scope.
-	// If Scope(DA) < Scope(DB), then prefer DA.  Similarly, if Scope(DA) >
-	// Scope(DB), then prefer DB.
-	if attrDA.Scope < attrDB.Scope {
-		return preferDA
-	}
-	if attrDA.Scope > attrDB.Scope {
-		return preferDB
-	}
-
-	// Rule 9: Use longest matching prefix.
-	// When DA and DB belong to the same address family (both are IPv6 or
-	// both are IPv4 [but see below]): If CommonPrefixLen(Source(DA), DA) >
-	// CommonPrefixLen(Source(DB), DB), then prefer DA.  Similarly, if
-	// CommonPrefixLen(Source(DA), DA) < CommonPrefixLen(Source(DB), DB),
-	// then prefer DB.
-	//
-	// However, applying this rule to IPv4 addresses causes
-	// problems (see issues 13283 and 18518), so limit to IPv6.
-	if DA.To4() == nil && DB.To4() == nil {
-		commonA := commonPrefixLen(SourceDA, DA)
-		commonB := commonPrefixLen(SourceDB, DB)
-
-		if commonA > commonB {
-			return preferDA
-		}
-		if commonA < commonB {
-			return preferDB
-		}
-	}
-
-	// Rule 10: Otherwise, leave the order unchanged.
-	// If DA preceded DB in the original list, prefer DA.
-	// Otherwise, prefer DB.
-	return false // "equal"
-}
-
-type policyTableEntry struct {
-	Prefix     *IPNet
-	Precedence uint8
-	Label      uint8
-}
-
-type policyTable []policyTableEntry
-
-// RFC 6724 section 2.1.
-var rfc6724policyTable = policyTable{
-	{
-		Prefix:     mustCIDR("::1/128"),
-		Precedence: 50,
-		Label:      0,
-	},
-	{
-		Prefix:     mustCIDR("::/0"),
-		Precedence: 40,
-		Label:      1,
-	},
-	{
-		// IPv4-compatible, etc.
-		Prefix:     mustCIDR("::ffff:0:0/96"),
-		Precedence: 35,
-		Label:      4,
-	},
-	{
-		// 6to4
-		Prefix:     mustCIDR("2002::/16"),
-		Precedence: 30,
-		Label:      2,
-	},
-	{
-		// Teredo
-		Prefix:     mustCIDR("2001::/32"),
-		Precedence: 5,
-		Label:      5,
-	},
-	{
-		Prefix:     mustCIDR("fc00::/7"),
-		Precedence: 3,
-		Label:      13,
-	},
-	{
-		Prefix:     mustCIDR("::/96"),
-		Precedence: 1,
-		Label:      3,
-	},
-	{
-		Prefix:     mustCIDR("fec0::/10"),
-		Precedence: 1,
-		Label:      11,
-	},
-	{
-		Prefix:     mustCIDR("3ffe::/16"),
-		Precedence: 1,
-		Label:      12,
-	},
-}
-
-func init() {
-	sort.Sort(sort.Reverse(byMaskLength(rfc6724policyTable)))
-}
-
-// byMaskLength sorts policyTableEntry by the size of their Prefix.Mask.Size,
-// from smallest mask, to largest.
-type byMaskLength []policyTableEntry
-
-func (s byMaskLength) Len() int      { return len(s) }
-func (s byMaskLength) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
-func (s byMaskLength) Less(i, j int) bool {
-	isize, _ := s[i].Prefix.Mask.Size()
-	jsize, _ := s[j].Prefix.Mask.Size()
-	return isize < jsize
-}
-
-// mustCIDR calls ParseCIDR and panics on any error, or if the network
-// is not IPv6.
-func mustCIDR(s string) *IPNet {
-	ip, ipNet, err := ParseCIDR(s)
-	if err != nil {
-		panic(err.Error())
-	}
-	if len(ip) != IPv6len {
-		panic("unexpected IP length")
-	}
-	return ipNet
-}
-
-// Classify returns the policyTableEntry of the entry with the longest
-// matching prefix that contains ip.
-// The table t must be sorted from largest mask size to smallest.
-func (t policyTable) Classify(ip IP) policyTableEntry {
-	for _, ent := range t {
-		if ent.Prefix.Contains(ip) {
-			return ent
-		}
-	}
-	return policyTableEntry{}
-}
-
-// RFC 6724 section 3.1.
-type scope uint8
-
-const (
-	scopeInterfaceLocal scope = 0x1
-	scopeLinkLocal      scope = 0x2
-	scopeAdminLocal     scope = 0x4
-	scopeSiteLocal      scope = 0x5
-	scopeOrgLocal       scope = 0x8
-	scopeGlobal         scope = 0xe
-)
-
-func classifyScope(ip IP) scope {
-	if ip.IsLoopback() || ip.IsLinkLocalUnicast() {
-		return scopeLinkLocal
-	}
-	ipv6 := len(ip) == IPv6len && ip.To4() == nil
-	if ipv6 && ip.IsMulticast() {
-		return scope(ip[1] & 0xf)
-	}
-	// Site-local addresses are defined in RFC 3513 section 2.5.6
-	// (and deprecated in RFC 3879).
-	if ipv6 && ip[0] == 0xfe && ip[1]&0xc0 == 0xc0 {
-		return scopeSiteLocal
-	}
-	return scopeGlobal
-}
-
-// commonPrefixLen reports the length of the longest prefix (looking
-// at the most significant, or leftmost, bits) that the
-// two addresses have in common, up to the length of a's prefix (i.e.,
-// the portion of the address not including the interface ID).
-//
-// If a or b is an IPv4 address as an IPv6 address, the IPv4 addresses
-// are compared (with max common prefix length of 32).
-// If a and b are different IP versions, 0 is returned.
-//
-// See https://tools.ietf.org/html/rfc6724#section-2.2
-func commonPrefixLen(a, b IP) (cpl int) {
-	if a4 := a.To4(); a4 != nil {
-		a = a4
-	}
-	if b4 := b.To4(); b4 != nil {
-		b = b4
-	}
-	if len(a) != len(b) {
-		return 0
-	}
-	// If IPv6, only up to the prefix (first 64 bits)
-	if len(a) > 8 {
-		a = a[:8]
-		b = b[:8]
-	}
-	for len(a) > 0 {
-		if a[0] == b[0] {
-			cpl += 8
-			a = a[1:]
-			b = b[1:]
-			continue
-		}
-		bits := 8
-		ab, bb := a[0], b[0]
-		for {
-			ab >>= 1
-			bb >>= 1
-			bits--
-			if ab == bb {
-				cpl += bits
-				return
-			}
-		}
-	}
-	return
-}
diff --git a/contrib/go/_std_1.18/src/net/cgo_unix.go b/contrib/go/_std_1.18/src/net/cgo_unix.go
deleted file mode 100644
index 6fc2c1930e..0000000000
--- a/contrib/go/_std_1.18/src/net/cgo_unix.go
+++ /dev/null
@@ -1,348 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build cgo && !netgo && (aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris)
-
-package net
-
-/*
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <netinet/in.h>
-#include <netdb.h>
-#include <unistd.h>
-#include <string.h>
-
-// If nothing else defined EAI_OVERFLOW, make sure it has a value.
-#ifndef EAI_OVERFLOW
-#define EAI_OVERFLOW -12
-#endif
-*/
-import "C"
-
-import (
-	"context"
-	"syscall"
-	"unsafe"
-)
-
-// An addrinfoErrno represents a getaddrinfo, getnameinfo-specific
-// error number. It's a signed number and a zero value is a non-error
-// by convention.
-type addrinfoErrno int
-
-func (eai addrinfoErrno) Error() string   { return C.GoString(C.gai_strerror(C.int(eai))) }
-func (eai addrinfoErrno) Temporary() bool { return eai == C.EAI_AGAIN }
-func (eai addrinfoErrno) Timeout() bool   { return false }
-
-type portLookupResult struct {
-	port int
-	err  error
-}
-
-type ipLookupResult struct {
-	addrs []IPAddr
-	cname string
-	err   error
-}
-
-type reverseLookupResult struct {
-	names []string
-	err   error
-}
-
-func cgoLookupHost(ctx context.Context, name string) (hosts []string, err error, completed bool) {
-	addrs, err, completed := cgoLookupIP(ctx, "ip", name)
-	for _, addr := range addrs {
-		hosts = append(hosts, addr.String())
-	}
-	return
-}
-
-func cgoLookupPort(ctx context.Context, network, service string) (port int, err error, completed bool) {
-	var hints C.struct_addrinfo
-	switch network {
-	case "": // no hints
-	case "tcp", "tcp4", "tcp6":
-		hints.ai_socktype = C.SOCK_STREAM
-		hints.ai_protocol = C.IPPROTO_TCP
-	case "udp", "udp4", "udp6":
-		hints.ai_socktype = C.SOCK_DGRAM
-		hints.ai_protocol = C.IPPROTO_UDP
-	default:
-		return 0, &DNSError{Err: "unknown network", Name: network + "/" + service}, true
-	}
-	switch ipVersion(network) {
-	case '4':
-		hints.ai_family = C.AF_INET
-	case '6':
-		hints.ai_family = C.AF_INET6
-	}
-	if ctx.Done() == nil {
-		port, err := cgoLookupServicePort(&hints, network, service)
-		return port, err, true
-	}
-	result := make(chan portLookupResult, 1)
-	go cgoPortLookup(result, &hints, network, service)
-	select {
-	case r := <-result:
-		return r.port, r.err, true
-	case <-ctx.Done():
-		// Since there isn't a portable way to cancel the lookup,
-		// we just let it finish and write to the buffered channel.
-		return 0, mapErr(ctx.Err()), false
-	}
-}
-
-func cgoLookupServicePort(hints *C.struct_addrinfo, network, service string) (port int, err error) {
-	cservice := make([]byte, len(service)+1)
-	copy(cservice, service)
-	// Lowercase the C service name.
-	for i, b := range cservice[:len(service)] {
-		cservice[i] = lowerASCII(b)
-	}
-	var res *C.struct_addrinfo
-	gerrno, err := C.getaddrinfo(nil, (*C.char)(unsafe.Pointer(&cservice[0])), hints, &res)
-	if gerrno != 0 {
-		isTemporary := false
-		switch gerrno {
-		case C.EAI_SYSTEM:
-			if err == nil { // see golang.org/issue/6232
-				err = syscall.EMFILE
-			}
-		default:
-			err = addrinfoErrno(gerrno)
-			isTemporary = addrinfoErrno(gerrno).Temporary()
-		}
-		return 0, &DNSError{Err: err.Error(), Name: network + "/" + service, IsTemporary: isTemporary}
-	}
-	defer C.freeaddrinfo(res)
-
-	for r := res; r != nil; r = r.ai_next {
-		switch r.ai_family {
-		case C.AF_INET:
-			sa := (*syscall.RawSockaddrInet4)(unsafe.Pointer(r.ai_addr))
-			p := (*[2]byte)(unsafe.Pointer(&sa.Port))
-			return int(p[0])<<8 | int(p[1]), nil
-		case C.AF_INET6:
-			sa := (*syscall.RawSockaddrInet6)(unsafe.Pointer(r.ai_addr))
-			p := (*[2]byte)(unsafe.Pointer(&sa.Port))
-			return int(p[0])<<8 | int(p[1]), nil
-		}
-	}
-	return 0, &DNSError{Err: "unknown port", Name: network + "/" + service}
-}
-
-func cgoPortLookup(result chan<- portLookupResult, hints *C.struct_addrinfo, network, service string) {
-	port, err := cgoLookupServicePort(hints, network, service)
-	result <- portLookupResult{port, err}
-}
-
-func cgoLookupIPCNAME(network, name string) (addrs []IPAddr, cname string, err error) {
-	acquireThread()
-	defer releaseThread()
-
-	var hints C.struct_addrinfo
-	hints.ai_flags = cgoAddrInfoFlags
-	hints.ai_socktype = C.SOCK_STREAM
-	hints.ai_family = C.AF_UNSPEC
-	switch ipVersion(network) {
-	case '4':
-		hints.ai_family = C.AF_INET
-	case '6':
-		hints.ai_family = C.AF_INET6
-	}
-
-	h := make([]byte, len(name)+1)
-	copy(h, name)
-	var res *C.struct_addrinfo
-	gerrno, err := C.getaddrinfo((*C.char)(unsafe.Pointer(&h[0])), nil, &hints, &res)
-	if gerrno != 0 {
-		isErrorNoSuchHost := false
-		isTemporary := false
-		switch gerrno {
-		case C.EAI_SYSTEM:
-			if err == nil {
-				// err should not be nil, but sometimes getaddrinfo returns
-				// gerrno == C.EAI_SYSTEM with err == nil on Linux.
-				// The report claims that it happens when we have too many
-				// open files, so use syscall.EMFILE (too many open files in system).
-				// Most system calls would return ENFILE (too many open files),
-				// so at the least EMFILE should be easy to recognize if this
-				// comes up again. golang.org/issue/6232.
-				err = syscall.EMFILE
-			}
-		case C.EAI_NONAME:
-			err = errNoSuchHost
-			isErrorNoSuchHost = true
-		default:
-			err = addrinfoErrno(gerrno)
-			isTemporary = addrinfoErrno(gerrno).Temporary()
-		}
-
-		return nil, "", &DNSError{Err: err.Error(), Name: name, IsNotFound: isErrorNoSuchHost, IsTemporary: isTemporary}
-	}
-	defer C.freeaddrinfo(res)
-
-	if res != nil {
-		cname = C.GoString(res.ai_canonname)
-		if cname == "" {
-			cname = name
-		}
-		if len(cname) > 0 && cname[len(cname)-1] != '.' {
-			cname += "."
-		}
-	}
-	for r := res; r != nil; r = r.ai_next {
-		// We only asked for SOCK_STREAM, but check anyhow.
-		if r.ai_socktype != C.SOCK_STREAM {
-			continue
-		}
-		switch r.ai_family {
-		case C.AF_INET:
-			sa := (*syscall.RawSockaddrInet4)(unsafe.Pointer(r.ai_addr))
-			addr := IPAddr{IP: copyIP(sa.Addr[:])}
-			addrs = append(addrs, addr)
-		case C.AF_INET6:
-			sa := (*syscall.RawSockaddrInet6)(unsafe.Pointer(r.ai_addr))
-			addr := IPAddr{IP: copyIP(sa.Addr[:]), Zone: zoneCache.name(int(sa.Scope_id))}
-			addrs = append(addrs, addr)
-		}
-	}
-	return addrs, cname, nil
-}
-
-func cgoIPLookup(result chan<- ipLookupResult, network, name string) {
-	addrs, cname, err := cgoLookupIPCNAME(network, name)
-	result <- ipLookupResult{addrs, cname, err}
-}
-
-func cgoLookupIP(ctx context.Context, network, name string) (addrs []IPAddr, err error, completed bool) {
-	if ctx.Done() == nil {
-		addrs, _, err = cgoLookupIPCNAME(network, name)
-		return addrs, err, true
-	}
-	result := make(chan ipLookupResult, 1)
-	go cgoIPLookup(result, network, name)
-	select {
-	case r := <-result:
-		return r.addrs, r.err, true
-	case <-ctx.Done():
-		return nil, mapErr(ctx.Err()), false
-	}
-}
-
-func cgoLookupCNAME(ctx context.Context, name string) (cname string, err error, completed bool) {
-	if ctx.Done() == nil {
-		_, cname, err = cgoLookupIPCNAME("ip", name)
-		return cname, err, true
-	}
-	result := make(chan ipLookupResult, 1)
-	go cgoIPLookup(result, "ip", name)
-	select {
-	case r := <-result:
-		return r.cname, r.err, true
-	case <-ctx.Done():
-		return "", mapErr(ctx.Err()), false
-	}
-}
-
-// These are roughly enough for the following:
-//
-// Source		Encoding			Maximum length of single name entry
-// Unicast DNS		ASCII or			<=253 + a NUL terminator
-//			Unicode in RFC 5892		252 * total number of labels + delimiters + a NUL terminator
-// Multicast DNS	UTF-8 in RFC 5198 or		<=253 + a NUL terminator
-//			the same as unicast DNS ASCII	<=253 + a NUL terminator
-// Local database	various				depends on implementation
-const (
-	nameinfoLen    = 64
-	maxNameinfoLen = 4096
-)
-
-func cgoLookupPTR(ctx context.Context, addr string) (names []string, err error, completed bool) {
-	var zone string
-	ip := parseIPv4(addr)
-	if ip == nil {
-		ip, zone = parseIPv6Zone(addr)
-	}
-	if ip == nil {
-		return nil, &DNSError{Err: "invalid address", Name: addr}, true
-	}
-	sa, salen := cgoSockaddr(ip, zone)
-	if sa == nil {
-		return nil, &DNSError{Err: "invalid address " + ip.String(), Name: addr}, true
-	}
-	if ctx.Done() == nil {
-		names, err := cgoLookupAddrPTR(addr, sa, salen)
-		return names, err, true
-	}
-	result := make(chan reverseLookupResult, 1)
-	go cgoReverseLookup(result, addr, sa, salen)
-	select {
-	case r := <-result:
-		return r.names, r.err, true
-	case <-ctx.Done():
-		return nil, mapErr(ctx.Err()), false
-	}
-}
-
-func cgoLookupAddrPTR(addr string, sa *C.struct_sockaddr, salen C.socklen_t) (names []string, err error) {
-	acquireThread()
-	defer releaseThread()
-
-	var gerrno int
-	var b []byte
-	for l := nameinfoLen; l <= maxNameinfoLen; l *= 2 {
-		b = make([]byte, l)
-		gerrno, err = cgoNameinfoPTR(b, sa, salen)
-		if gerrno == 0 || gerrno != C.EAI_OVERFLOW {
-			break
-		}
-	}
-	if gerrno != 0 {
-		isTemporary := false
-		switch gerrno {
-		case C.EAI_SYSTEM:
-			if err == nil { // see golang.org/issue/6232
-				err = syscall.EMFILE
-			}
-		default:
-			err = addrinfoErrno(gerrno)
-			isTemporary = addrinfoErrno(gerrno).Temporary()
-		}
-		return nil, &DNSError{Err: err.Error(), Name: addr, IsTemporary: isTemporary}
-	}
-	for i := 0; i < len(b); i++ {
-		if b[i] == 0 {
-			b = b[:i]
-			break
-		}
-	}
-	return []string{absDomainName(string(b))}, nil
-}
-
-func cgoReverseLookup(result chan<- reverseLookupResult, addr string, sa *C.struct_sockaddr, salen C.socklen_t) {
-	names, err := cgoLookupAddrPTR(addr, sa, salen)
-	result <- reverseLookupResult{names, err}
-}
-
-func cgoSockaddr(ip IP, zone string) (*C.struct_sockaddr, C.socklen_t) {
-	if ip4 := ip.To4(); ip4 != nil {
-		return cgoSockaddrInet4(ip4), C.socklen_t(syscall.SizeofSockaddrInet4)
-	}
-	if ip6 := ip.To16(); ip6 != nil {
-		return cgoSockaddrInet6(ip6, zoneCache.index(zone)), C.socklen_t(syscall.SizeofSockaddrInet6)
-	}
-	return nil, 0
-}
-
-func copyIP(x IP) IP {
-	if len(x) < 16 {
-		return x.To16()
-	}
-	y := make(IP, len(x))
-	copy(y, x)
-	return y
-}
diff --git a/contrib/go/_std_1.18/src/net/conf.go b/contrib/go/_std_1.18/src/net/conf.go
deleted file mode 100644
index 415caedacc..0000000000
--- a/contrib/go/_std_1.18/src/net/conf.go
+++ /dev/null
@@ -1,320 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
-
-package net
-
-import (
-	"internal/bytealg"
-	"internal/godebug"
-	"os"
-	"runtime"
-	"sync"
-	"syscall"
-)
-
-// conf represents a system's network configuration.
-type conf struct {
-	// forceCgoLookupHost forces CGO to always be used, if available.
-	forceCgoLookupHost bool
-
-	netGo  bool // go DNS resolution forced
-	netCgo bool // cgo DNS resolution forced
-
-	// machine has an /etc/mdns.allow file
-	hasMDNSAllow bool
-
-	goos          string // the runtime.GOOS, to ease testing
-	dnsDebugLevel int
-
-	nss    *nssConf
-	resolv *dnsConfig
-}
-
-var (
-	confOnce sync.Once // guards init of confVal via initConfVal
-	confVal  = &conf{goos: runtime.GOOS}
-)
-
-// systemConf returns the machine's network configuration.
-func systemConf() *conf {
-	confOnce.Do(initConfVal)
-	return confVal
-}
-
-func initConfVal() {
-	dnsMode, debugLevel := goDebugNetDNS()
-	confVal.dnsDebugLevel = debugLevel
-	confVal.netGo = netGo || dnsMode == "go"
-	confVal.netCgo = netCgo || dnsMode == "cgo"
-
-	if confVal.dnsDebugLevel > 0 {
-		defer func() {
-			switch {
-			case confVal.netGo:
-				if netGo {
-					println("go package net: built with netgo build tag; using Go's DNS resolver")
-				} else {
-					println("go package net: GODEBUG setting forcing use of Go's resolver")
-				}
-			case confVal.forceCgoLookupHost:
-				println("go package net: using cgo DNS resolver")
-			default:
-				println("go package net: dynamic selection of DNS resolver")
-			}
-		}()
-	}
-
-	// Darwin pops up annoying dialog boxes if programs try to do
-	// their own DNS requests. So always use cgo instead, which
-	// avoids that.
-	if runtime.GOOS == "darwin" || runtime.GOOS == "ios" {
-		confVal.forceCgoLookupHost = true
-		return
-	}
-
-	// If any environment-specified resolver options are specified,
-	// force cgo. Note that LOCALDOMAIN can change behavior merely
-	// by being specified with the empty string.
-	_, localDomainDefined := syscall.Getenv("LOCALDOMAIN")
-	if os.Getenv("RES_OPTIONS") != "" ||
-		os.Getenv("HOSTALIASES") != "" ||
-		confVal.netCgo ||
-		localDomainDefined {
-		confVal.forceCgoLookupHost = true
-		return
-	}
-
-	// OpenBSD apparently lets you override the location of resolv.conf
-	// with ASR_CONFIG. If we notice that, defer to libc.
-	if runtime.GOOS == "openbsd" && os.Getenv("ASR_CONFIG") != "" {
-		confVal.forceCgoLookupHost = true
-		return
-	}
-
-	if runtime.GOOS != "openbsd" {
-		confVal.nss = parseNSSConfFile("/etc/nsswitch.conf")
-	}
-
-	confVal.resolv = dnsReadConfig("/etc/resolv.conf")
-	if confVal.resolv.err != nil && !os.IsNotExist(confVal.resolv.err) &&
-		!os.IsPermission(confVal.resolv.err) {
-		// If we can't read the resolv.conf file, assume it
-		// had something important in it and defer to cgo.
-		// libc's resolver might then fail too, but at least
-		// it wasn't our fault.
-		confVal.forceCgoLookupHost = true
-	}
-
-	if _, err := os.Stat("/etc/mdns.allow"); err == nil {
-		confVal.hasMDNSAllow = true
-	}
-}
-
-// canUseCgo reports whether calling cgo functions is allowed
-// for non-hostname lookups.
-func (c *conf) canUseCgo() bool {
-	return c.hostLookupOrder(nil, "") == hostLookupCgo
-}
-
-// hostLookupOrder determines which strategy to use to resolve hostname.
-// The provided Resolver is optional. nil means to not consider its options.
-func (c *conf) hostLookupOrder(r *Resolver, hostname string) (ret hostLookupOrder) {
-	if c.dnsDebugLevel > 1 {
-		defer func() {
-			print("go package net: hostLookupOrder(", hostname, ") = ", ret.String(), "\n")
-		}()
-	}
-	fallbackOrder := hostLookupCgo
-	if c.netGo || r.preferGo() {
-		fallbackOrder = hostLookupFilesDNS
-	}
-	if c.forceCgoLookupHost || c.resolv.unknownOpt || c.goos == "android" {
-		return fallbackOrder
-	}
-	if bytealg.IndexByteString(hostname, '\\') != -1 || bytealg.IndexByteString(hostname, '%') != -1 {
-		// Don't deal with special form hostnames with backslashes
-		// or '%'.
-		return fallbackOrder
-	}
-
-	// OpenBSD is unique and doesn't use nsswitch.conf.
-	// It also doesn't support mDNS.
-	if c.goos == "openbsd" {
-		// OpenBSD's resolv.conf manpage says that a non-existent
-		// resolv.conf means "lookup" defaults to only "files",
-		// without DNS lookups.
-		if os.IsNotExist(c.resolv.err) {
-			return hostLookupFiles
-		}
-		lookup := c.resolv.lookup
-		if len(lookup) == 0 {
-			// https://www.openbsd.org/cgi-bin/man.cgi/OpenBSD-current/man5/resolv.conf.5
-			// "If the lookup keyword is not used in the
-			// system's resolv.conf file then the assumed
-			// order is 'bind file'"
-			return hostLookupDNSFiles
-		}
-		if len(lookup) < 1 || len(lookup) > 2 {
-			return fallbackOrder
-		}
-		switch lookup[0] {
-		case "bind":
-			if len(lookup) == 2 {
-				if lookup[1] == "file" {
-					return hostLookupDNSFiles
-				}
-				return fallbackOrder
-			}
-			return hostLookupDNS
-		case "file":
-			if len(lookup) == 2 {
-				if lookup[1] == "bind" {
-					return hostLookupFilesDNS
-				}
-				return fallbackOrder
-			}
-			return hostLookupFiles
-		default:
-			return fallbackOrder
-		}
-	}
-
-	// Canonicalize the hostname by removing any trailing dot.
-	if stringsHasSuffix(hostname, ".") {
-		hostname = hostname[:len(hostname)-1]
-	}
-	if stringsHasSuffixFold(hostname, ".local") {
-		// Per RFC 6762, the ".local" TLD is special. And
-		// because Go's native resolver doesn't do mDNS or
-		// similar local resolution mechanisms, assume that
-		// libc might (via Avahi, etc) and use cgo.
-		return fallbackOrder
-	}
-
-	nss := c.nss
-	srcs := nss.sources["hosts"]
-	// If /etc/nsswitch.conf doesn't exist or doesn't specify any
-	// sources for "hosts", assume Go's DNS will work fine.
-	if os.IsNotExist(nss.err) || (nss.err == nil && len(srcs) == 0) {
-		if c.goos == "solaris" {
-			// illumos defaults to "nis [NOTFOUND=return] files"
-			return fallbackOrder
-		}
-		return hostLookupFilesDNS
-	}
-	if nss.err != nil {
-		// We failed to parse or open nsswitch.conf, so
-		// conservatively assume we should use cgo if it's
-		// available.
-		return fallbackOrder
-	}
-
-	var mdnsSource, filesSource, dnsSource bool
-	var first string
-	for _, src := range srcs {
-		if src.source == "myhostname" {
-			if isLocalhost(hostname) || isGateway(hostname) {
-				return fallbackOrder
-			}
-			hn, err := getHostname()
-			if err != nil || stringsEqualFold(hostname, hn) {
-				return fallbackOrder
-			}
-			continue
-		}
-		if src.source == "files" || src.source == "dns" {
-			if !src.standardCriteria() {
-				return fallbackOrder // non-standard; let libc deal with it.
-			}
-			if src.source == "files" {
-				filesSource = true
-			} else if src.source == "dns" {
-				dnsSource = true
-			}
-			if first == "" {
-				first = src.source
-			}
-			continue
-		}
-		if stringsHasPrefix(src.source, "mdns") {
-			// e.g. "mdns4", "mdns4_minimal"
-			// We already returned true before if it was *.local.
-			// libc wouldn't have found a hit on this anyway.
-			mdnsSource = true
-			continue
-		}
-		// Some source we don't know how to deal with.
-		return fallbackOrder
-	}
-
-	// We don't parse mdns.allow files. They're rare. If one
-	// exists, it might list other TLDs (besides .local) or even
-	// '*', so just let libc deal with it.
-	if mdnsSource && c.hasMDNSAllow {
-		return fallbackOrder
-	}
-
-	// Cases where Go can handle it without cgo and C thread
-	// overhead.
-	switch {
-	case filesSource && dnsSource:
-		if first == "files" {
-			return hostLookupFilesDNS
-		} else {
-			return hostLookupDNSFiles
-		}
-	case filesSource:
-		return hostLookupFiles
-	case dnsSource:
-		return hostLookupDNS
-	}
-
-	// Something weird. Let libc deal with it.
-	return fallbackOrder
-}
-
-// goDebugNetDNS parses the value of the GODEBUG "netdns" value.
-// The netdns value can be of the form:
-//    1       // debug level 1
-//    2       // debug level 2
-//    cgo     // use cgo for DNS lookups
-//    go      // use go for DNS lookups
-//    cgo+1   // use cgo for DNS lookups + debug level 1
-//    1+cgo   // same
-//    cgo+2   // same, but debug level 2
-// etc.
-func goDebugNetDNS() (dnsMode string, debugLevel int) {
-	goDebug := godebug.Get("netdns")
-	parsePart := func(s string) {
-		if s == "" {
-			return
-		}
-		if '0' <= s[0] && s[0] <= '9' {
-			debugLevel, _, _ = dtoi(s)
-		} else {
-			dnsMode = s
-		}
-	}
-	if i := bytealg.IndexByteString(goDebug, '+'); i != -1 {
-		parsePart(goDebug[:i])
-		parsePart(goDebug[i+1:])
-		return
-	}
-	parsePart(goDebug)
-	return
-}
-
-// isLocalhost reports whether h should be considered a "localhost"
-// name for the myhostname NSS module.
-func isLocalhost(h string) bool {
-	return stringsEqualFold(h, "localhost") || stringsEqualFold(h, "localhost.localdomain") || stringsHasSuffixFold(h, ".localhost") || stringsHasSuffixFold(h, ".localhost.localdomain")
-}
-
-// isGateway reports whether h should be considered a "gateway"
-// name for the myhostname NSS module.
-func isGateway(h string) bool {
-	return stringsEqualFold(h, "gateway")
-}
diff --git a/contrib/go/_std_1.18/src/net/dial.go b/contrib/go/_std_1.18/src/net/dial.go
deleted file mode 100644
index 486ced0f2a..0000000000
--- a/contrib/go/_std_1.18/src/net/dial.go
+++ /dev/null
@@ -1,743 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package net
-
-import (
-	"context"
-	"internal/nettrace"
-	"syscall"
-	"time"
-)
-
-// defaultTCPKeepAlive is a default constant value for TCPKeepAlive times
-// See golang.org/issue/31510
-const (
-	defaultTCPKeepAlive = 15 * time.Second
-)
-
-// A Dialer contains options for connecting to an address.
-//
-// The zero value for each field is equivalent to dialing
-// without that option. Dialing with the zero value of Dialer
-// is therefore equivalent to just calling the Dial function.
-//
-// It is safe to call Dialer's methods concurrently.
-type Dialer struct {
-	// Timeout is the maximum amount of time a dial will wait for
-	// a connect to complete. If Deadline is also set, it may fail
-	// earlier.
-	//
-	// The default is no timeout.
-	//
-	// When using TCP and dialing a host name with multiple IP
-	// addresses, the timeout may be divided between them.
-	//
-	// With or without a timeout, the operating system may impose
-	// its own earlier timeout. For instance, TCP timeouts are
-	// often around 3 minutes.
-	Timeout time.Duration
-
-	// Deadline is the absolute point in time after which dials
-	// will fail. If Timeout is set, it may fail earlier.
-	// Zero means no deadline, or dependent on the operating system
-	// as with the Timeout option.
-	Deadline time.Time
-
-	// LocalAddr is the local address to use when dialing an
-	// address. The address must be of a compatible type for the
-	// network being dialed.
-	// If nil, a local address is automatically chosen.
-	LocalAddr Addr
-
-	// DualStack previously enabled RFC 6555 Fast Fallback
-	// support, also known as "Happy Eyeballs", in which IPv4 is
-	// tried soon if IPv6 appears to be misconfigured and
-	// hanging.
-	//
-	// Deprecated: Fast Fallback is enabled by default. To
-	// disable, set FallbackDelay to a negative value.
-	DualStack bool
-
-	// FallbackDelay specifies the length of time to wait before
-	// spawning a RFC 6555 Fast Fallback connection. That is, this
-	// is the amount of time to wait for IPv6 to succeed before
-	// assuming that IPv6 is misconfigured and falling back to
-	// IPv4.
-	//
-	// If zero, a default delay of 300ms is used.
-	// A negative value disables Fast Fallback support.
-	FallbackDelay time.Duration
-
-	// KeepAlive specifies the interval between keep-alive
-	// probes for an active network connection.
-	// If zero, keep-alive probes are sent with a default value
-	// (currently 15 seconds), if supported by the protocol and operating
-	// system. Network protocols or operating systems that do
-	// not support keep-alives ignore this field.
-	// If negative, keep-alive probes are disabled.
-	KeepAlive time.Duration
-
-	// Resolver optionally specifies an alternate resolver to use.
-	Resolver *Resolver
-
-	// Cancel is an optional channel whose closure indicates that
-	// the dial should be canceled. Not all types of dials support
-	// cancellation.
-	//
-	// Deprecated: Use DialContext instead.
-	Cancel <-chan struct{}
-
-	// If Control is not nil, it is called after creating the network
-	// connection but before actually dialing.
-	//
-	// Network and address parameters passed to Control method are not
-	// necessarily the ones passed to Dial. For example, passing "tcp" to Dial
-	// will cause the Control function to be called with "tcp4" or "tcp6".
-	Control func(network, address string, c syscall.RawConn) error
-}
-
-func (d *Dialer) dualStack() bool { return d.FallbackDelay >= 0 }
-
-func minNonzeroTime(a, b time.Time) time.Time {
-	if a.IsZero() {
-		return b
-	}
-	if b.IsZero() || a.Before(b) {
-		return a
-	}
-	return b
-}
-
-// deadline returns the earliest of:
-//   - now+Timeout
-//   - d.Deadline
-//   - the context's deadline
-// Or zero, if none of Timeout, Deadline, or context's deadline is set.
-func (d *Dialer) deadline(ctx context.Context, now time.Time) (earliest time.Time) {
-	if d.Timeout != 0 { // including negative, for historical reasons
-		earliest = now.Add(d.Timeout)
-	}
-	if d, ok := ctx.Deadline(); ok {
-		earliest = minNonzeroTime(earliest, d)
-	}
-	return minNonzeroTime(earliest, d.Deadline)
-}
-
-func (d *Dialer) resolver() *Resolver {
-	if d.Resolver != nil {
-		return d.Resolver
-	}
-	return DefaultResolver
-}
-
-// partialDeadline returns the deadline to use for a single address,
-// when multiple addresses are pending.
-func partialDeadline(now, deadline time.Time, addrsRemaining int) (time.Time, error) {
-	if deadline.IsZero() {
-		return deadline, nil
-	}
-	timeRemaining := deadline.Sub(now)
-	if timeRemaining <= 0 {
-		return time.Time{}, errTimeout
-	}
-	// Tentatively allocate equal time to each remaining address.
-	timeout := timeRemaining / time.Duration(addrsRemaining)
-	// If the time per address is too short, steal from the end of the list.
-	const saneMinimum = 2 * time.Second
-	if timeout < saneMinimum {
-		if timeRemaining < saneMinimum {
-			timeout = timeRemaining
-		} else {
-			timeout = saneMinimum
-		}
-	}
-	return now.Add(timeout), nil
-}
-
-func (d *Dialer) fallbackDelay() time.Duration {
-	if d.FallbackDelay > 0 {
-		return d.FallbackDelay
-	} else {
-		return 300 * time.Millisecond
-	}
-}
-
-func parseNetwork(ctx context.Context, network string, needsProto bool) (afnet string, proto int, err error) {
-	i := last(network, ':')
-	if i < 0 { // no colon
-		switch network {
-		case "tcp", "tcp4", "tcp6":
-		case "udp", "udp4", "udp6":
-		case "ip", "ip4", "ip6":
-			if needsProto {
-				return "", 0, UnknownNetworkError(network)
-			}
-		case "unix", "unixgram", "unixpacket":
-		default:
-			return "", 0, UnknownNetworkError(network)
-		}
-		return network, 0, nil
-	}
-	afnet = network[:i]
-	switch afnet {
-	case "ip", "ip4", "ip6":
-		protostr := network[i+1:]
-		proto, i, ok := dtoi(protostr)
-		if !ok || i != len(protostr) {
-			proto, err = lookupProtocol(ctx, protostr)
-			if err != nil {
-				return "", 0, err
-			}
-		}
-		return afnet, proto, nil
-	}
-	return "", 0, UnknownNetworkError(network)
-}
-
-// resolveAddrList resolves addr using hint and returns a list of
-// addresses. The result contains at least one address when error is
-// nil.
-func (r *Resolver) resolveAddrList(ctx context.Context, op, network, addr string, hint Addr) (addrList, error) {
-	afnet, _, err := parseNetwork(ctx, network, true)
-	if err != nil {
-		return nil, err
-	}
-	if op == "dial" && addr == "" {
-		return nil, errMissingAddress
-	}
-	switch afnet {
-	case "unix", "unixgram", "unixpacket":
-		addr, err := ResolveUnixAddr(afnet, addr)
-		if err != nil {
-			return nil, err
-		}
-		if op == "dial" && hint != nil && addr.Network() != hint.Network() {
-			return nil, &AddrError{Err: "mismatched local address type", Addr: hint.String()}
-		}
-		return addrList{addr}, nil
-	}
-	addrs, err := r.internetAddrList(ctx, afnet, addr)
-	if err != nil || op != "dial" || hint == nil {
-		return addrs, err
-	}
-	var (
-		tcp      *TCPAddr
-		udp      *UDPAddr
-		ip       *IPAddr
-		wildcard bool
-	)
-	switch hint := hint.(type) {
-	case *TCPAddr:
-		tcp = hint
-		wildcard = tcp.isWildcard()
-	case *UDPAddr:
-		udp = hint
-		wildcard = udp.isWildcard()
-	case *IPAddr:
-		ip = hint
-		wildcard = ip.isWildcard()
-	}
-	naddrs := addrs[:0]
-	for _, addr := range addrs {
-		if addr.Network() != hint.Network() {
-			return nil, &AddrError{Err: "mismatched local address type", Addr: hint.String()}
-		}
-		switch addr := addr.(type) {
-		case *TCPAddr:
-			if !wildcard && !addr.isWildcard() && !addr.IP.matchAddrFamily(tcp.IP) {
-				continue
-			}
-			naddrs = append(naddrs, addr)
-		case *UDPAddr:
-			if !wildcard && !addr.isWildcard() && !addr.IP.matchAddrFamily(udp.IP) {
-				continue
-			}
-			naddrs = append(naddrs, addr)
-		case *IPAddr:
-			if !wildcard && !addr.isWildcard() && !addr.IP.matchAddrFamily(ip.IP) {
-				continue
-			}
-			naddrs = append(naddrs, addr)
-		}
-	}
-	if len(naddrs) == 0 {
-		return nil, &AddrError{Err: errNoSuitableAddress.Error(), Addr: hint.String()}
-	}
-	return naddrs, nil
-}
-
-// Dial connects to the address on the named network.
-//
-// Known networks are "tcp", "tcp4" (IPv4-only), "tcp6" (IPv6-only),
-// "udp", "udp4" (IPv4-only), "udp6" (IPv6-only), "ip", "ip4"
-// (IPv4-only), "ip6" (IPv6-only), "unix", "unixgram" and
-// "unixpacket".
-//
-// For TCP and UDP networks, the address has the form "host:port".
-// The host must be a literal IP address, or a host name that can be
-// resolved to IP addresses.
-// The port must be a literal port number or a service name.
-// If the host is a literal IPv6 address it must be enclosed in square
-// brackets, as in "[2001:db8::1]:80" or "[fe80::1%zone]:80".
-// The zone specifies the scope of the literal IPv6 address as defined
-// in RFC 4007.
-// The functions JoinHostPort and SplitHostPort manipulate a pair of
-// host and port in this form.
-// When using TCP, and the host resolves to multiple IP addresses,
-// Dial will try each IP address in order until one succeeds.
-//
-// Examples:
-//	Dial("tcp", "golang.org:http")
-//	Dial("tcp", "192.0.2.1:http")
-//	Dial("tcp", "198.51.100.1:80")
-//	Dial("udp", "[2001:db8::1]:domain")
-//	Dial("udp", "[fe80::1%lo0]:53")
-//	Dial("tcp", ":80")
-//
-// For IP networks, the network must be "ip", "ip4" or "ip6" followed
-// by a colon and a literal protocol number or a protocol name, and
-// the address has the form "host". The host must be a literal IP
-// address or a literal IPv6 address with zone.
-// It depends on each operating system how the operating system
-// behaves with a non-well known protocol number such as "0" or "255".
-//
-// Examples:
-//	Dial("ip4:1", "192.0.2.1")
-//	Dial("ip6:ipv6-icmp", "2001:db8::1")
-//	Dial("ip6:58", "fe80::1%lo0")
-//
-// For TCP, UDP and IP networks, if the host is empty or a literal
-// unspecified IP address, as in ":80", "0.0.0.0:80" or "[::]:80" for
-// TCP and UDP, "", "0.0.0.0" or "::" for IP, the local system is
-// assumed.
-//
-// For Unix networks, the address must be a file system path.
-func Dial(network, address string) (Conn, error) {
-	var d Dialer
-	return d.Dial(network, address)
-}
-
-// DialTimeout acts like Dial but takes a timeout.
-//
-// The timeout includes name resolution, if required.
-// When using TCP, and the host in the address parameter resolves to
-// multiple IP addresses, the timeout is spread over each consecutive
-// dial, such that each is given an appropriate fraction of the time
-// to connect.
-//
-// See func Dial for a description of the network and address
-// parameters.
-func DialTimeout(network, address string, timeout time.Duration) (Conn, error) {
-	d := Dialer{Timeout: timeout}
-	return d.Dial(network, address)
-}
-
-// sysDialer contains a Dial's parameters and configuration.
-type sysDialer struct {
-	Dialer
-	network, address string
-}
-
-// Dial connects to the address on the named network.
-//
-// See func Dial for a description of the network and address
-// parameters.
-//
-// Dial uses context.Background internally; to specify the context, use
-// DialContext.
-func (d *Dialer) Dial(network, address string) (Conn, error) {
-	return d.DialContext(context.Background(), network, address)
-}
-
-// DialContext connects to the address on the named network using
-// the provided context.
-//
-// The provided Context must be non-nil. If the context expires before
-// the connection is complete, an error is returned. Once successfully
-// connected, any expiration of the context will not affect the
-// connection.
-//
-// When using TCP, and the host in the address parameter resolves to multiple
-// network addresses, any dial timeout (from d.Timeout or ctx) is spread
-// over each consecutive dial, such that each is given an appropriate
-// fraction of the time to connect.
-// For example, if a host has 4 IP addresses and the timeout is 1 minute,
-// the connect to each single address will be given 15 seconds to complete
-// before trying the next one.
-//
-// See func Dial for a description of the network and address
-// parameters.
-func (d *Dialer) DialContext(ctx context.Context, network, address string) (Conn, error) {
-	if ctx == nil {
-		panic("nil context")
-	}
-	deadline := d.deadline(ctx, time.Now())
-	if !deadline.IsZero() {
-		if d, ok := ctx.Deadline(); !ok || deadline.Before(d) {
-			subCtx, cancel := context.WithDeadline(ctx, deadline)
-			defer cancel()
-			ctx = subCtx
-		}
-	}
-	if oldCancel := d.Cancel; oldCancel != nil {
-		subCtx, cancel := context.WithCancel(ctx)
-		defer cancel()
-		go func() {
-			select {
-			case <-oldCancel:
-				cancel()
-			case <-subCtx.Done():
-			}
-		}()
-		ctx = subCtx
-	}
-
-	// Shadow the nettrace (if any) during resolve so Connect events don't fire for DNS lookups.
-	resolveCtx := ctx
-	if trace, _ := ctx.Value(nettrace.TraceKey{}).(*nettrace.Trace); trace != nil {
-		shadow := *trace
-		shadow.ConnectStart = nil
-		shadow.ConnectDone = nil
-		resolveCtx = context.WithValue(resolveCtx, nettrace.TraceKey{}, &shadow)
-	}
-
-	addrs, err := d.resolver().resolveAddrList(resolveCtx, "dial", network, address, d.LocalAddr)
-	if err != nil {
-		return nil, &OpError{Op: "dial", Net: network, Source: nil, Addr: nil, Err: err}
-	}
-
-	sd := &sysDialer{
-		Dialer:  *d,
-		network: network,
-		address: address,
-	}
-
-	var primaries, fallbacks addrList
-	if d.dualStack() && network == "tcp" {
-		primaries, fallbacks = addrs.partition(isIPv4)
-	} else {
-		primaries = addrs
-	}
-
-	var c Conn
-	if len(fallbacks) > 0 {
-		c, err = sd.dialParallel(ctx, primaries, fallbacks)
-	} else {
-		c, err = sd.dialSerial(ctx, primaries)
-	}
-	if err != nil {
-		return nil, err
-	}
-
-	if tc, ok := c.(*TCPConn); ok && d.KeepAlive >= 0 {
-		setKeepAlive(tc.fd, true)
-		ka := d.KeepAlive
-		if d.KeepAlive == 0 {
-			ka = defaultTCPKeepAlive
-		}
-		setKeepAlivePeriod(tc.fd, ka)
-		testHookSetKeepAlive(ka)
-	}
-	return c, nil
-}
-
-// dialParallel races two copies of dialSerial, giving the first a
-// head start. It returns the first established connection and
-// closes the others. Otherwise it returns an error from the first
-// primary address.
-func (sd *sysDialer) dialParallel(ctx context.Context, primaries, fallbacks addrList) (Conn, error) {
-	if len(fallbacks) == 0 {
-		return sd.dialSerial(ctx, primaries)
-	}
-
-	returned := make(chan struct{})
-	defer close(returned)
-
-	type dialResult struct {
-		Conn
-		error
-		primary bool
-		done    bool
-	}
-	results := make(chan dialResult) // unbuffered
-
-	startRacer := func(ctx context.Context, primary bool) {
-		ras := primaries
-		if !primary {
-			ras = fallbacks
-		}
-		c, err := sd.dialSerial(ctx, ras)
-		select {
-		case results <- dialResult{Conn: c, error: err, primary: primary, done: true}:
-		case <-returned:
-			if c != nil {
-				c.Close()
-			}
-		}
-	}
-
-	var primary, fallback dialResult
-
-	// Start the main racer.
-	primaryCtx, primaryCancel := context.WithCancel(ctx)
-	defer primaryCancel()
-	go startRacer(primaryCtx, true)
-
-	// Start the timer for the fallback racer.
-	fallbackTimer := time.NewTimer(sd.fallbackDelay())
-	defer fallbackTimer.Stop()
-
-	for {
-		select {
-		case <-fallbackTimer.C:
-			fallbackCtx, fallbackCancel := context.WithCancel(ctx)
-			defer fallbackCancel()
-			go startRacer(fallbackCtx, false)
-
-		case res := <-results:
-			if res.error == nil {
-				return res.Conn, nil
-			}
-			if res.primary {
-				primary = res
-			} else {
-				fallback = res
-			}
-			if primary.done && fallback.done {
-				return nil, primary.error
-			}
-			if res.primary && fallbackTimer.Stop() {
-				// If we were able to stop the timer, that means it
-				// was running (hadn't yet started the fallback), but
-				// we just got an error on the primary path, so start
-				// the fallback immediately (in 0 nanoseconds).
-				fallbackTimer.Reset(0)
-			}
-		}
-	}
-}
-
-// dialSerial connects to a list of addresses in sequence, returning
-// either the first successful connection, or the first error.
-func (sd *sysDialer) dialSerial(ctx context.Context, ras addrList) (Conn, error) {
-	var firstErr error // The error from the first address is most relevant.
-
-	for i, ra := range ras {
-		select {
-		case <-ctx.Done():
-			return nil, &OpError{Op: "dial", Net: sd.network, Source: sd.LocalAddr, Addr: ra, Err: mapErr(ctx.Err())}
-		default:
-		}
-
-		dialCtx := ctx
-		if deadline, hasDeadline := ctx.Deadline(); hasDeadline {
-			partialDeadline, err := partialDeadline(time.Now(), deadline, len(ras)-i)
-			if err != nil {
-				// Ran out of time.
-				if firstErr == nil {
-					firstErr = &OpError{Op: "dial", Net: sd.network, Source: sd.LocalAddr, Addr: ra, Err: err}
-				}
-				break
-			}
-			if partialDeadline.Before(deadline) {
-				var cancel context.CancelFunc
-				dialCtx, cancel = context.WithDeadline(ctx, partialDeadline)
-				defer cancel()
-			}
-		}
-
-		c, err := sd.dialSingle(dialCtx, ra)
-		if err == nil {
-			return c, nil
-		}
-		if firstErr == nil {
-			firstErr = err
-		}
-	}
-
-	if firstErr == nil {
-		firstErr = &OpError{Op: "dial", Net: sd.network, Source: nil, Addr: nil, Err: errMissingAddress}
-	}
-	return nil, firstErr
-}
-
-// dialSingle attempts to establish and returns a single connection to
-// the destination address.
-func (sd *sysDialer) dialSingle(ctx context.Context, ra Addr) (c Conn, err error) {
-	trace, _ := ctx.Value(nettrace.TraceKey{}).(*nettrace.Trace)
-	if trace != nil {
-		raStr := ra.String()
-		if trace.ConnectStart != nil {
-			trace.ConnectStart(sd.network, raStr)
-		}
-		if trace.ConnectDone != nil {
-			defer func() { trace.ConnectDone(sd.network, raStr, err) }()
-		}
-	}
-	la := sd.LocalAddr
-	switch ra := ra.(type) {
-	case *TCPAddr:
-		la, _ := la.(*TCPAddr)
-		c, err = sd.dialTCP(ctx, la, ra)
-	case *UDPAddr:
-		la, _ := la.(*UDPAddr)
-		c, err = sd.dialUDP(ctx, la, ra)
-	case *IPAddr:
-		la, _ := la.(*IPAddr)
-		c, err = sd.dialIP(ctx, la, ra)
-	case *UnixAddr:
-		la, _ := la.(*UnixAddr)
-		c, err = sd.dialUnix(ctx, la, ra)
-	default:
-		return nil, &OpError{Op: "dial", Net: sd.network, Source: la, Addr: ra, Err: &AddrError{Err: "unexpected address type", Addr: sd.address}}
-	}
-	if err != nil {
-		return nil, &OpError{Op: "dial", Net: sd.network, Source: la, Addr: ra, Err: err} // c is non-nil interface containing nil pointer
-	}
-	return c, nil
-}
-
-// ListenConfig contains options for listening to an address.
-type ListenConfig struct {
-	// If Control is not nil, it is called after creating the network
-	// connection but before binding it to the operating system.
-	//
-	// Network and address parameters passed to Control method are not
-	// necessarily the ones passed to Listen. For example, passing "tcp" to
-	// Listen will cause the Control function to be called with "tcp4" or "tcp6".
-	Control func(network, address string, c syscall.RawConn) error
-
-	// KeepAlive specifies the keep-alive period for network
-	// connections accepted by this listener.
-	// If zero, keep-alives are enabled if supported by the protocol
-	// and operating system. Network protocols or operating systems
-	// that do not support keep-alives ignore this field.
-	// If negative, keep-alives are disabled.
-	KeepAlive time.Duration
-}
-
-// Listen announces on the local network address.
-//
-// See func Listen for a description of the network and address
-// parameters.
-func (lc *ListenConfig) Listen(ctx context.Context, network, address string) (Listener, error) {
-	addrs, err := DefaultResolver.resolveAddrList(ctx, "listen", network, address, nil)
-	if err != nil {
-		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: nil, Err: err}
-	}
-	sl := &sysListener{
-		ListenConfig: *lc,
-		network:      network,
-		address:      address,
-	}
-	var l Listener
-	la := addrs.first(isIPv4)
-	switch la := la.(type) {
-	case *TCPAddr:
-		l, err = sl.listenTCP(ctx, la)
-	case *UnixAddr:
-		l, err = sl.listenUnix(ctx, la)
-	default:
-		return nil, &OpError{Op: "listen", Net: sl.network, Source: nil, Addr: la, Err: &AddrError{Err: "unexpected address type", Addr: address}}
-	}
-	if err != nil {
-		return nil, &OpError{Op: "listen", Net: sl.network, Source: nil, Addr: la, Err: err} // l is non-nil interface containing nil pointer
-	}
-	return l, nil
-}
-
-// ListenPacket announces on the local network address.
-//
-// See func ListenPacket for a description of the network and address
-// parameters.
-func (lc *ListenConfig) ListenPacket(ctx context.Context, network, address string) (PacketConn, error) {
-	addrs, err := DefaultResolver.resolveAddrList(ctx, "listen", network, address, nil)
-	if err != nil {
-		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: nil, Err: err}
-	}
-	sl := &sysListener{
-		ListenConfig: *lc,
-		network:      network,
-		address:      address,
-	}
-	var c PacketConn
-	la := addrs.first(isIPv4)
-	switch la := la.(type) {
-	case *UDPAddr:
-		c, err = sl.listenUDP(ctx, la)
-	case *IPAddr:
-		c, err = sl.listenIP(ctx, la)
-	case *UnixAddr:
-		c, err = sl.listenUnixgram(ctx, la)
-	default:
-		return nil, &OpError{Op: "listen", Net: sl.network, Source: nil, Addr: la, Err: &AddrError{Err: "unexpected address type", Addr: address}}
-	}
-	if err != nil {
-		return nil, &OpError{Op: "listen", Net: sl.network, Source: nil, Addr: la, Err: err} // c is non-nil interface containing nil pointer
-	}
-	return c, nil
-}
-
-// sysListener contains a Listen's parameters and configuration.
-type sysListener struct {
-	ListenConfig
-	network, address string
-}
-
-// Listen announces on the local network address.
-//
-// The network must be "tcp", "tcp4", "tcp6", "unix" or "unixpacket".
-//
-// For TCP networks, if the host in the address parameter is empty or
-// a literal unspecified IP address, Listen listens on all available
-// unicast and anycast IP addresses of the local system.
-// To only use IPv4, use network "tcp4".
-// The address can use a host name, but this is not recommended,
-// because it will create a listener for at most one of the host's IP
-// addresses.
-// If the port in the address parameter is empty or "0", as in
-// "127.0.0.1:" or "[::1]:0", a port number is automatically chosen.
-// The Addr method of Listener can be used to discover the chosen
-// port.
-//
-// See func Dial for a description of the network and address
-// parameters.
-//
-// Listen uses context.Background internally; to specify the context, use
-// ListenConfig.Listen.
-func Listen(network, address string) (Listener, error) {
-	var lc ListenConfig
-	return lc.Listen(context.Background(), network, address)
-}
-
-// ListenPacket announces on the local network address.
-//
-// The network must be "udp", "udp4", "udp6", "unixgram", or an IP
-// transport. The IP transports are "ip", "ip4", or "ip6" followed by
-// a colon and a literal protocol number or a protocol name, as in
-// "ip:1" or "ip:icmp".
-//
-// For UDP and IP networks, if the host in the address parameter is
-// empty or a literal unspecified IP address, ListenPacket listens on
-// all available IP addresses of the local system except multicast IP
-// addresses.
-// To only use IPv4, use network "udp4" or "ip4:proto".
-// The address can use a host name, but this is not recommended,
-// because it will create a listener for at most one of the host's IP
-// addresses.
-// If the port in the address parameter is empty or "0", as in
-// "127.0.0.1:" or "[::1]:0", a port number is automatically chosen.
-// The LocalAddr method of PacketConn can be used to discover the
-// chosen port.
-//
-// See func Dial for a description of the network and address
-// parameters.
-//
-// ListenPacket uses context.Background internally; to specify the context, use
-// ListenConfig.ListenPacket.
-func ListenPacket(network, address string) (PacketConn, error) {
-	var lc ListenConfig
-	return lc.ListenPacket(context.Background(), network, address)
-}
diff --git a/contrib/go/_std_1.18/src/net/dnsclient.go b/contrib/go/_std_1.18/src/net/dnsclient.go
deleted file mode 100644
index a779c37e53..0000000000
--- a/contrib/go/_std_1.18/src/net/dnsclient.go
+++ /dev/null
@@ -1,231 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package net
-
-import (
-	"internal/bytealg"
-	"internal/itoa"
-	"sort"
-
-	"golang.org/x/net/dns/dnsmessage"
-)
-
-// provided by runtime
-func fastrand() uint32
-
-func randInt() int {
-	x, y := fastrand(), fastrand()    // 32-bit halves
-	u := uint(x)<<31 ^ uint(int32(y)) // full uint, even on 64-bit systems; avoid 32-bit shift on 32-bit systems
-	i := int(u >> 1)                  // clear sign bit, even on 32-bit systems
-	return i
-}
-
-func randIntn(n int) int {
-	return randInt() % n
-}
-
-// reverseaddr returns the in-addr.arpa. or ip6.arpa. hostname of the IP
-// address addr suitable for rDNS (PTR) record lookup or an error if it fails
-// to parse the IP address.
-func reverseaddr(addr string) (arpa string, err error) {
-	ip := ParseIP(addr)
-	if ip == nil {
-		return "", &DNSError{Err: "unrecognized address", Name: addr}
-	}
-	if ip.To4() != nil {
-		return itoa.Uitoa(uint(ip[15])) + "." + itoa.Uitoa(uint(ip[14])) + "." + itoa.Uitoa(uint(ip[13])) + "." + itoa.Uitoa(uint(ip[12])) + ".in-addr.arpa.", nil
-	}
-	// Must be IPv6
-	buf := make([]byte, 0, len(ip)*4+len("ip6.arpa."))
-	// Add it, in reverse, to the buffer
-	for i := len(ip) - 1; i >= 0; i-- {
-		v := ip[i]
-		buf = append(buf, hexDigit[v&0xF],
-			'.',
-			hexDigit[v>>4],
-			'.')
-	}
-	// Append "ip6.arpa." and return (buf already has the final .)
-	buf = append(buf, "ip6.arpa."...)
-	return string(buf), nil
-}
-
-func equalASCIIName(x, y dnsmessage.Name) bool {
-	if x.Length != y.Length {
-		return false
-	}
-	for i := 0; i < int(x.Length); i++ {
-		a := x.Data[i]
-		b := y.Data[i]
-		if 'A' <= a && a <= 'Z' {
-			a += 0x20
-		}
-		if 'A' <= b && b <= 'Z' {
-			b += 0x20
-		}
-		if a != b {
-			return false
-		}
-	}
-	return true
-}
-
-// isDomainName checks if a string is a presentation-format domain name
-// (currently restricted to hostname-compatible "preferred name" LDH labels and
-// SRV-like "underscore labels"; see golang.org/issue/12421).
-func isDomainName(s string) bool {
-	// The root domain name is valid. See golang.org/issue/45715.
-	if s == "." {
-		return true
-	}
-
-	// See RFC 1035, RFC 3696.
-	// Presentation format has dots before every label except the first, and the
-	// terminal empty label is optional here because we assume fully-qualified
-	// (absolute) input. We must therefore reserve space for the first and last
-	// labels' length octets in wire format, where they are necessary and the
-	// maximum total length is 255.
-	// So our _effective_ maximum is 253, but 254 is not rejected if the last
-	// character is a dot.
-	l := len(s)
-	if l == 0 || l > 254 || l == 254 && s[l-1] != '.' {
-		return false
-	}
-
-	last := byte('.')
-	nonNumeric := false // true once we've seen a letter or hyphen
-	partlen := 0
-	for i := 0; i < len(s); i++ {
-		c := s[i]
-		switch {
-		default:
-			return false
-		case 'a' <= c && c <= 'z' || 'A' <= c && c <= 'Z' || c == '_':
-			nonNumeric = true
-			partlen++
-		case '0' <= c && c <= '9':
-			// fine
-			partlen++
-		case c == '-':
-			// Byte before dash cannot be dot.
-			if last == '.' {
-				return false
-			}
-			partlen++
-			nonNumeric = true
-		case c == '.':
-			// Byte before dot cannot be dot, dash.
-			if last == '.' || last == '-' {
-				return false
-			}
-			if partlen > 63 || partlen == 0 {
-				return false
-			}
-			partlen = 0
-		}
-		last = c
-	}
-	if last == '-' || partlen > 63 {
-		return false
-	}
-
-	return nonNumeric
-}
-
-// absDomainName returns an absolute domain name which ends with a
-// trailing dot to match pure Go reverse resolver and all other lookup
-// routines.
-// See golang.org/issue/12189.
-// But we don't want to add dots for local names from /etc/hosts.
-// It's hard to tell so we settle on the heuristic that names without dots
-// (like "localhost" or "myhost") do not get trailing dots, but any other
-// names do.
-func absDomainName(s string) string {
-	if bytealg.IndexByteString(s, '.') != -1 && s[len(s)-1] != '.' {
-		s += "."
-	}
-	return s
-}
-
-// An SRV represents a single DNS SRV record.
-type SRV struct {
-	Target   string
-	Port     uint16
-	Priority uint16
-	Weight   uint16
-}
-
-// byPriorityWeight sorts SRV records by ascending priority and weight.
-type byPriorityWeight []*SRV
-
-func (s byPriorityWeight) Len() int { return len(s) }
-func (s byPriorityWeight) Less(i, j int) bool {
-	return s[i].Priority < s[j].Priority || (s[i].Priority == s[j].Priority && s[i].Weight < s[j].Weight)
-}
-func (s byPriorityWeight) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
-
-// shuffleByWeight shuffles SRV records by weight using the algorithm
-// described in RFC 2782.
-func (addrs byPriorityWeight) shuffleByWeight() {
-	sum := 0
-	for _, addr := range addrs {
-		sum += int(addr.Weight)
-	}
-	for sum > 0 && len(addrs) > 1 {
-		s := 0
-		n := randIntn(sum)
-		for i := range addrs {
-			s += int(addrs[i].Weight)
-			if s > n {
-				if i > 0 {
-					addrs[0], addrs[i] = addrs[i], addrs[0]
-				}
-				break
-			}
-		}
-		sum -= int(addrs[0].Weight)
-		addrs = addrs[1:]
-	}
-}
-
-// sort reorders SRV records as specified in RFC 2782.
-func (addrs byPriorityWeight) sort() {
-	sort.Sort(addrs)
-	i := 0
-	for j := 1; j < len(addrs); j++ {
-		if addrs[i].Priority != addrs[j].Priority {
-			addrs[i:j].shuffleByWeight()
-			i = j
-		}
-	}
-	addrs[i:].shuffleByWeight()
-}
-
-// An MX represents a single DNS MX record.
-type MX struct {
-	Host string
-	Pref uint16
-}
-
-// byPref implements sort.Interface to sort MX records by preference
-type byPref []*MX
-
-func (s byPref) Len() int           { return len(s) }
-func (s byPref) Less(i, j int) bool { return s[i].Pref < s[j].Pref }
-func (s byPref) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
-
-// sort reorders MX records as specified in RFC 5321.
-func (s byPref) sort() {
-	for i := range s {
-		j := randIntn(i + 1)
-		s[i], s[j] = s[j], s[i]
-	}
-	sort.Sort(s)
-}
-
-// An NS represents a single DNS NS record.
-type NS struct {
-	Host string
-}
diff --git a/contrib/go/_std_1.18/src/net/dnsclient_unix.go b/contrib/go/_std_1.18/src/net/dnsclient_unix.go
deleted file mode 100644
index 9a4a6ee68c..0000000000
--- a/contrib/go/_std_1.18/src/net/dnsclient_unix.go
+++ /dev/null
@@ -1,800 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
-
-// DNS client: see RFC 1035.
-// Has to be linked into package net for Dial.
-
-// TODO(rsc):
-//	Could potentially handle many outstanding lookups faster.
-//	Random UDP source port (net.Dial should do that for us).
-//	Random request IDs.
-
-package net
-
-import (
-	"context"
-	"errors"
-	"internal/itoa"
-	"io"
-	"os"
-	"sync"
-	"time"
-
-	"golang.org/x/net/dns/dnsmessage"
-)
-
-const (
-	// to be used as a useTCP parameter to exchange
-	useTCPOnly  = true
-	useUDPOrTCP = false
-
-	// Maximum DNS packet size.
-	// Value taken from https://dnsflagday.net/2020/.
-	maxDNSPacketSize = 1232
-)
-
-var (
-	errLameReferral              = errors.New("lame referral")
-	errCannotUnmarshalDNSMessage = errors.New("cannot unmarshal DNS message")
-	errCannotMarshalDNSMessage   = errors.New("cannot marshal DNS message")
-	errServerMisbehaving         = errors.New("server misbehaving")
-	errInvalidDNSResponse        = errors.New("invalid DNS response")
-	errNoAnswerFromDNSServer     = errors.New("no answer from DNS server")
-
-	// errServerTemporarilyMisbehaving is like errServerMisbehaving, except
-	// that when it gets translated to a DNSError, the IsTemporary field
-	// gets set to true.
-	errServerTemporarilyMisbehaving = errors.New("server misbehaving")
-)
-
-func newRequest(q dnsmessage.Question) (id uint16, udpReq, tcpReq []byte, err error) {
-	id = uint16(randInt())
-	b := dnsmessage.NewBuilder(make([]byte, 2, 514), dnsmessage.Header{ID: id, RecursionDesired: true})
-	b.EnableCompression()
-	if err := b.StartQuestions(); err != nil {
-		return 0, nil, nil, err
-	}
-	if err := b.Question(q); err != nil {
-		return 0, nil, nil, err
-	}
-	tcpReq, err = b.Finish()
-	udpReq = tcpReq[2:]
-	l := len(tcpReq) - 2
-	tcpReq[0] = byte(l >> 8)
-	tcpReq[1] = byte(l)
-	return id, udpReq, tcpReq, err
-}
-
-func checkResponse(reqID uint16, reqQues dnsmessage.Question, respHdr dnsmessage.Header, respQues dnsmessage.Question) bool {
-	if !respHdr.Response {
-		return false
-	}
-	if reqID != respHdr.ID {
-		return false
-	}
-	if reqQues.Type != respQues.Type || reqQues.Class != respQues.Class || !equalASCIIName(reqQues.Name, respQues.Name) {
-		return false
-	}
-	return true
-}
-
-func dnsPacketRoundTrip(c Conn, id uint16, query dnsmessage.Question, b []byte) (dnsmessage.Parser, dnsmessage.Header, error) {
-	if _, err := c.Write(b); err != nil {
-		return dnsmessage.Parser{}, dnsmessage.Header{}, err
-	}
-
-	b = make([]byte, maxDNSPacketSize)
-	for {
-		n, err := c.Read(b)
-		if err != nil {
-			return dnsmessage.Parser{}, dnsmessage.Header{}, err
-		}
-		var p dnsmessage.Parser
-		// Ignore invalid responses as they may be malicious
-		// forgery attempts. Instead continue waiting until
-		// timeout. See golang.org/issue/13281.
-		h, err := p.Start(b[:n])
-		if err != nil {
-			continue
-		}
-		q, err := p.Question()
-		if err != nil || !checkResponse(id, query, h, q) {
-			continue
-		}
-		return p, h, nil
-	}
-}
-
-func dnsStreamRoundTrip(c Conn, id uint16, query dnsmessage.Question, b []byte) (dnsmessage.Parser, dnsmessage.Header, error) {
-	if _, err := c.Write(b); err != nil {
-		return dnsmessage.Parser{}, dnsmessage.Header{}, err
-	}
-
-	b = make([]byte, 1280) // 1280 is a reasonable initial size for IP over Ethernet, see RFC 4035
-	if _, err := io.ReadFull(c, b[:2]); err != nil {
-		return dnsmessage.Parser{}, dnsmessage.Header{}, err
-	}
-	l := int(b[0])<<8 | int(b[1])
-	if l > len(b) {
-		b = make([]byte, l)
-	}
-	n, err := io.ReadFull(c, b[:l])
-	if err != nil {
-		return dnsmessage.Parser{}, dnsmessage.Header{}, err
-	}
-	var p dnsmessage.Parser
-	h, err := p.Start(b[:n])
-	if err != nil {
-		return dnsmessage.Parser{}, dnsmessage.Header{}, errCannotUnmarshalDNSMessage
-	}
-	q, err := p.Question()
-	if err != nil {
-		return dnsmessage.Parser{}, dnsmessage.Header{}, errCannotUnmarshalDNSMessage
-	}
-	if !checkResponse(id, query, h, q) {
-		return dnsmessage.Parser{}, dnsmessage.Header{}, errInvalidDNSResponse
-	}
-	return p, h, nil
-}
-
-// exchange sends a query on the connection and hopes for a response.
-func (r *Resolver) exchange(ctx context.Context, server string, q dnsmessage.Question, timeout time.Duration, useTCP bool) (dnsmessage.Parser, dnsmessage.Header, error) {
-	q.Class = dnsmessage.ClassINET
-	id, udpReq, tcpReq, err := newRequest(q)
-	if err != nil {
-		return dnsmessage.Parser{}, dnsmessage.Header{}, errCannotMarshalDNSMessage
-	}
-	var networks []string
-	if useTCP {
-		networks = []string{"tcp"}
-	} else {
-		networks = []string{"udp", "tcp"}
-	}
-	for _, network := range networks {
-		ctx, cancel := context.WithDeadline(ctx, time.Now().Add(timeout))
-		defer cancel()
-
-		c, err := r.dial(ctx, network, server)
-		if err != nil {
-			return dnsmessage.Parser{}, dnsmessage.Header{}, err
-		}
-		if d, ok := ctx.Deadline(); ok && !d.IsZero() {
-			c.SetDeadline(d)
-		}
-		var p dnsmessage.Parser
-		var h dnsmessage.Header
-		if _, ok := c.(PacketConn); ok {
-			p, h, err = dnsPacketRoundTrip(c, id, q, udpReq)
-		} else {
-			p, h, err = dnsStreamRoundTrip(c, id, q, tcpReq)
-		}
-		c.Close()
-		if err != nil {
-			return dnsmessage.Parser{}, dnsmessage.Header{}, mapErr(err)
-		}
-		if err := p.SkipQuestion(); err != dnsmessage.ErrSectionDone {
-			return dnsmessage.Parser{}, dnsmessage.Header{}, errInvalidDNSResponse
-		}
-		if h.Truncated { // see RFC 5966
-			continue
-		}
-		return p, h, nil
-	}
-	return dnsmessage.Parser{}, dnsmessage.Header{}, errNoAnswerFromDNSServer
-}
-
-// checkHeader performs basic sanity checks on the header.
-func checkHeader(p *dnsmessage.Parser, h dnsmessage.Header) error {
-	if h.RCode == dnsmessage.RCodeNameError {
-		return errNoSuchHost
-	}
-
-	_, err := p.AnswerHeader()
-	if err != nil && err != dnsmessage.ErrSectionDone {
-		return errCannotUnmarshalDNSMessage
-	}
-
-	// libresolv continues to the next server when it receives
-	// an invalid referral response. See golang.org/issue/15434.
-	if h.RCode == dnsmessage.RCodeSuccess && !h.Authoritative && !h.RecursionAvailable && err == dnsmessage.ErrSectionDone {
-		return errLameReferral
-	}
-
-	if h.RCode != dnsmessage.RCodeSuccess && h.RCode != dnsmessage.RCodeNameError {
-		// None of the error codes make sense
-		// for the query we sent. If we didn't get
-		// a name error and we didn't get success,
-		// the server is behaving incorrectly or
-		// having temporary trouble.
-		if h.RCode == dnsmessage.RCodeServerFailure {
-			return errServerTemporarilyMisbehaving
-		}
-		return errServerMisbehaving
-	}
-
-	return nil
-}
-
-func skipToAnswer(p *dnsmessage.Parser, qtype dnsmessage.Type) error {
-	for {
-		h, err := p.AnswerHeader()
-		if err == dnsmessage.ErrSectionDone {
-			return errNoSuchHost
-		}
-		if err != nil {
-			return errCannotUnmarshalDNSMessage
-		}
-		if h.Type == qtype {
-			return nil
-		}
-		if err := p.SkipAnswer(); err != nil {
-			return errCannotUnmarshalDNSMessage
-		}
-	}
-}
-
-// Do a lookup for a single name, which must be rooted
-// (otherwise answer will not find the answers).
-func (r *Resolver) tryOneName(ctx context.Context, cfg *dnsConfig, name string, qtype dnsmessage.Type) (dnsmessage.Parser, string, error) {
-	var lastErr error
-	serverOffset := cfg.serverOffset()
-	sLen := uint32(len(cfg.servers))
-
-	n, err := dnsmessage.NewName(name)
-	if err != nil {
-		return dnsmessage.Parser{}, "", errCannotMarshalDNSMessage
-	}
-	q := dnsmessage.Question{
-		Name:  n,
-		Type:  qtype,
-		Class: dnsmessage.ClassINET,
-	}
-
-	for i := 0; i < cfg.attempts; i++ {
-		for j := uint32(0); j < sLen; j++ {
-			server := cfg.servers[(serverOffset+j)%sLen]
-
-			p, h, err := r.exchange(ctx, server, q, cfg.timeout, cfg.useTCP)
-			if err != nil {
-				dnsErr := &DNSError{
-					Err:    err.Error(),
-					Name:   name,
-					Server: server,
-				}
-				if nerr, ok := err.(Error); ok && nerr.Timeout() {
-					dnsErr.IsTimeout = true
-				}
-				// Set IsTemporary for socket-level errors. Note that this flag
-				// may also be used to indicate a SERVFAIL response.
-				if _, ok := err.(*OpError); ok {
-					dnsErr.IsTemporary = true
-				}
-				lastErr = dnsErr
-				continue
-			}
-
-			if err := checkHeader(&p, h); err != nil {
-				dnsErr := &DNSError{
-					Err:    err.Error(),
-					Name:   name,
-					Server: server,
-				}
-				if err == errServerTemporarilyMisbehaving {
-					dnsErr.IsTemporary = true
-				}
-				if err == errNoSuchHost {
-					// The name does not exist, so trying
-					// another server won't help.
-
-					dnsErr.IsNotFound = true
-					return p, server, dnsErr
-				}
-				lastErr = dnsErr
-				continue
-			}
-
-			err = skipToAnswer(&p, qtype)
-			if err == nil {
-				return p, server, nil
-			}
-			lastErr = &DNSError{
-				Err:    err.Error(),
-				Name:   name,
-				Server: server,
-			}
-			if err == errNoSuchHost {
-				// The name does not exist, so trying another
-				// server won't help.
-
-				lastErr.(*DNSError).IsNotFound = true
-				return p, server, lastErr
-			}
-		}
-	}
-	return dnsmessage.Parser{}, "", lastErr
-}
-
-// A resolverConfig represents a DNS stub resolver configuration.
-type resolverConfig struct {
-	initOnce sync.Once // guards init of resolverConfig
-
-	// ch is used as a semaphore that only allows one lookup at a
-	// time to recheck resolv.conf.
-	ch          chan struct{} // guards lastChecked and modTime
-	lastChecked time.Time     // last time resolv.conf was checked
-
-	mu        sync.RWMutex // protects dnsConfig
-	dnsConfig *dnsConfig   // parsed resolv.conf structure used in lookups
-}
-
-var resolvConf resolverConfig
-
-// init initializes conf and is only called via conf.initOnce.
-func (conf *resolverConfig) init() {
-	// Set dnsConfig and lastChecked so we don't parse
-	// resolv.conf twice the first time.
-	conf.dnsConfig = systemConf().resolv
-	if conf.dnsConfig == nil {
-		conf.dnsConfig = dnsReadConfig("/etc/resolv.conf")
-	}
-	conf.lastChecked = time.Now()
-
-	// Prepare ch so that only one update of resolverConfig may
-	// run at once.
-	conf.ch = make(chan struct{}, 1)
-}
-
-// tryUpdate tries to update conf with the named resolv.conf file.
-// The name variable only exists for testing. It is otherwise always
-// "/etc/resolv.conf".
-func (conf *resolverConfig) tryUpdate(name string) {
-	conf.initOnce.Do(conf.init)
-
-	// Ensure only one update at a time checks resolv.conf.
-	if !conf.tryAcquireSema() {
-		return
-	}
-	defer conf.releaseSema()
-
-	now := time.Now()
-	if conf.lastChecked.After(now.Add(-5 * time.Second)) {
-		return
-	}
-	conf.lastChecked = now
-
-	var mtime time.Time
-	if fi, err := os.Stat(name); err == nil {
-		mtime = fi.ModTime()
-	}
-	if mtime.Equal(conf.dnsConfig.mtime) {
-		return
-	}
-
-	dnsConf := dnsReadConfig(name)
-	conf.mu.Lock()
-	conf.dnsConfig = dnsConf
-	conf.mu.Unlock()
-}
-
-func (conf *resolverConfig) tryAcquireSema() bool {
-	select {
-	case conf.ch <- struct{}{}:
-		return true
-	default:
-		return false
-	}
-}
-
-func (conf *resolverConfig) releaseSema() {
-	<-conf.ch
-}
-
-func (r *Resolver) lookup(ctx context.Context, name string, qtype dnsmessage.Type) (dnsmessage.Parser, string, error) {
-	if !isDomainName(name) {
-		// We used to use "invalid domain name" as the error,
-		// but that is a detail of the specific lookup mechanism.
-		// Other lookups might allow broader name syntax
-		// (for example Multicast DNS allows UTF-8; see RFC 6762).
-		// For consistency with libc resolvers, report no such host.
-		return dnsmessage.Parser{}, "", &DNSError{Err: errNoSuchHost.Error(), Name: name, IsNotFound: true}
-	}
-	resolvConf.tryUpdate("/etc/resolv.conf")
-	resolvConf.mu.RLock()
-	conf := resolvConf.dnsConfig
-	resolvConf.mu.RUnlock()
-	var (
-		p      dnsmessage.Parser
-		server string
-		err    error
-	)
-	for _, fqdn := range conf.nameList(name) {
-		p, server, err = r.tryOneName(ctx, conf, fqdn, qtype)
-		if err == nil {
-			break
-		}
-		if nerr, ok := err.(Error); ok && nerr.Temporary() && r.strictErrors() {
-			// If we hit a temporary error with StrictErrors enabled,
-			// stop immediately instead of trying more names.
-			break
-		}
-	}
-	if err == nil {
-		return p, server, nil
-	}
-	if err, ok := err.(*DNSError); ok {
-		// Show original name passed to lookup, not suffixed one.
-		// In general we might have tried many suffixes; showing
-		// just one is misleading. See also golang.org/issue/6324.
-		err.Name = name
-	}
-	return dnsmessage.Parser{}, "", err
-}
-
-// avoidDNS reports whether this is a hostname for which we should not
-// use DNS. Currently this includes only .onion, per RFC 7686. See
-// golang.org/issue/13705. Does not cover .local names (RFC 6762),
-// see golang.org/issue/16739.
-func avoidDNS(name string) bool {
-	if name == "" {
-		return true
-	}
-	if name[len(name)-1] == '.' {
-		name = name[:len(name)-1]
-	}
-	return stringsHasSuffixFold(name, ".onion")
-}
-
-// nameList returns a list of names for sequential DNS queries.
-func (conf *dnsConfig) nameList(name string) []string {
-	if avoidDNS(name) {
-		return nil
-	}
-
-	// Check name length (see isDomainName).
-	l := len(name)
-	rooted := l > 0 && name[l-1] == '.'
-	if l > 254 || l == 254 && rooted {
-		return nil
-	}
-
-	// If name is rooted (trailing dot), try only that name.
-	if rooted {
-		return []string{name}
-	}
-
-	hasNdots := count(name, '.') >= conf.ndots
-	name += "."
-	l++
-
-	// Build list of search choices.
-	names := make([]string, 0, 1+len(conf.search))
-	// If name has enough dots, try unsuffixed first.
-	if hasNdots {
-		names = append(names, name)
-	}
-	// Try suffixes that are not too long (see isDomainName).
-	for _, suffix := range conf.search {
-		if l+len(suffix) <= 254 {
-			names = append(names, name+suffix)
-		}
-	}
-	// Try unsuffixed, if not tried first above.
-	if !hasNdots {
-		names = append(names, name)
-	}
-	return names
-}
-
-// hostLookupOrder specifies the order of LookupHost lookup strategies.
-// It is basically a simplified representation of nsswitch.conf.
-// "files" means /etc/hosts.
-type hostLookupOrder int
-
-const (
-	// hostLookupCgo means defer to cgo.
-	hostLookupCgo      hostLookupOrder = iota
-	hostLookupFilesDNS                 // files first
-	hostLookupDNSFiles                 // dns first
-	hostLookupFiles                    // only files
-	hostLookupDNS                      // only DNS
-)
-
-var lookupOrderName = map[hostLookupOrder]string{
-	hostLookupCgo:      "cgo",
-	hostLookupFilesDNS: "files,dns",
-	hostLookupDNSFiles: "dns,files",
-	hostLookupFiles:    "files",
-	hostLookupDNS:      "dns",
-}
-
-func (o hostLookupOrder) String() string {
-	if s, ok := lookupOrderName[o]; ok {
-		return s
-	}
-	return "hostLookupOrder=" + itoa.Itoa(int(o)) + "??"
-}
-
-// goLookupHost is the native Go implementation of LookupHost.
-// Used only if cgoLookupHost refuses to handle the request
-// (that is, only if cgoLookupHost is the stub in cgo_stub.go).
-// Normally we let cgo use the C library resolver instead of
-// depending on our lookup code, so that Go and C get the same
-// answers.
-func (r *Resolver) goLookupHost(ctx context.Context, name string) (addrs []string, err error) {
-	return r.goLookupHostOrder(ctx, name, hostLookupFilesDNS)
-}
-
-func (r *Resolver) goLookupHostOrder(ctx context.Context, name string, order hostLookupOrder) (addrs []string, err error) {
-	if order == hostLookupFilesDNS || order == hostLookupFiles {
-		// Use entries from /etc/hosts if they match.
-		addrs = lookupStaticHost(name)
-		if len(addrs) > 0 || order == hostLookupFiles {
-			return
-		}
-	}
-	ips, _, err := r.goLookupIPCNAMEOrder(ctx, "ip", name, order)
-	if err != nil {
-		return
-	}
-	addrs = make([]string, 0, len(ips))
-	for _, ip := range ips {
-		addrs = append(addrs, ip.String())
-	}
-	return
-}
-
-// lookup entries from /etc/hosts
-func goLookupIPFiles(name string) (addrs []IPAddr) {
-	for _, haddr := range lookupStaticHost(name) {
-		haddr, zone := splitHostZone(haddr)
-		if ip := ParseIP(haddr); ip != nil {
-			addr := IPAddr{IP: ip, Zone: zone}
-			addrs = append(addrs, addr)
-		}
-	}
-	sortByRFC6724(addrs)
-	return
-}
-
-// goLookupIP is the native Go implementation of LookupIP.
-// The libc versions are in cgo_*.go.
-func (r *Resolver) goLookupIP(ctx context.Context, network, host string) (addrs []IPAddr, err error) {
-	order := systemConf().hostLookupOrder(r, host)
-	addrs, _, err = r.goLookupIPCNAMEOrder(ctx, network, host, order)
-	return
-}
-
-func (r *Resolver) goLookupIPCNAMEOrder(ctx context.Context, network, name string, order hostLookupOrder) (addrs []IPAddr, cname dnsmessage.Name, err error) {
-	if order == hostLookupFilesDNS || order == hostLookupFiles {
-		addrs = goLookupIPFiles(name)
-		if len(addrs) > 0 || order == hostLookupFiles {
-			return addrs, dnsmessage.Name{}, nil
-		}
-	}
-	if !isDomainName(name) {
-		// See comment in func lookup above about use of errNoSuchHost.
-		return nil, dnsmessage.Name{}, &DNSError{Err: errNoSuchHost.Error(), Name: name, IsNotFound: true}
-	}
-	resolvConf.tryUpdate("/etc/resolv.conf")
-	resolvConf.mu.RLock()
-	conf := resolvConf.dnsConfig
-	resolvConf.mu.RUnlock()
-	type result struct {
-		p      dnsmessage.Parser
-		server string
-		error
-	}
-	lane := make(chan result, 1)
-	qtypes := []dnsmessage.Type{dnsmessage.TypeA, dnsmessage.TypeAAAA}
-	switch ipVersion(network) {
-	case '4':
-		qtypes = []dnsmessage.Type{dnsmessage.TypeA}
-	case '6':
-		qtypes = []dnsmessage.Type{dnsmessage.TypeAAAA}
-	}
-	var queryFn func(fqdn string, qtype dnsmessage.Type)
-	var responseFn func(fqdn string, qtype dnsmessage.Type) result
-	if conf.singleRequest {
-		queryFn = func(fqdn string, qtype dnsmessage.Type) {}
-		responseFn = func(fqdn string, qtype dnsmessage.Type) result {
-			dnsWaitGroup.Add(1)
-			defer dnsWaitGroup.Done()
-			p, server, err := r.tryOneName(ctx, conf, fqdn, qtype)
-			return result{p, server, err}
-		}
-	} else {
-		queryFn = func(fqdn string, qtype dnsmessage.Type) {
-			dnsWaitGroup.Add(1)
-			go func(qtype dnsmessage.Type) {
-				p, server, err := r.tryOneName(ctx, conf, fqdn, qtype)
-				lane <- result{p, server, err}
-				dnsWaitGroup.Done()
-			}(qtype)
-		}
-		responseFn = func(fqdn string, qtype dnsmessage.Type) result {
-			return <-lane
-		}
-	}
-	var lastErr error
-	for _, fqdn := range conf.nameList(name) {
-		for _, qtype := range qtypes {
-			queryFn(fqdn, qtype)
-		}
-		hitStrictError := false
-		for _, qtype := range qtypes {
-			result := responseFn(fqdn, qtype)
-			if result.error != nil {
-				if nerr, ok := result.error.(Error); ok && nerr.Temporary() && r.strictErrors() {
-					// This error will abort the nameList loop.
-					hitStrictError = true
-					lastErr = result.error
-				} else if lastErr == nil || fqdn == name+"." {
-					// Prefer error for original name.
-					lastErr = result.error
-				}
-				continue
-			}
-
-			// Presotto says it's okay to assume that servers listed in
-			// /etc/resolv.conf are recursive resolvers.
-			//
-			// We asked for recursion, so it should have included all the
-			// answers we need in this one packet.
-			//
-			// Further, RFC 1035 section 4.3.1 says that "the recursive
-			// response to a query will be... The answer to the query,
-			// possibly preface by one or more CNAME RRs that specify
-			// aliases encountered on the way to an answer."
-			//
-			// Therefore, we should be able to assume that we can ignore
-			// CNAMEs and that the A and AAAA records we requested are
-			// for the canonical name.
-
-		loop:
-			for {
-				h, err := result.p.AnswerHeader()
-				if err != nil && err != dnsmessage.ErrSectionDone {
-					lastErr = &DNSError{
-						Err:    "cannot marshal DNS message",
-						Name:   name,
-						Server: result.server,
-					}
-				}
-				if err != nil {
-					break
-				}
-				switch h.Type {
-				case dnsmessage.TypeA:
-					a, err := result.p.AResource()
-					if err != nil {
-						lastErr = &DNSError{
-							Err:    "cannot marshal DNS message",
-							Name:   name,
-							Server: result.server,
-						}
-						break loop
-					}
-					addrs = append(addrs, IPAddr{IP: IP(a.A[:])})
-
-				case dnsmessage.TypeAAAA:
-					aaaa, err := result.p.AAAAResource()
-					if err != nil {
-						lastErr = &DNSError{
-							Err:    "cannot marshal DNS message",
-							Name:   name,
-							Server: result.server,
-						}
-						break loop
-					}
-					addrs = append(addrs, IPAddr{IP: IP(aaaa.AAAA[:])})
-
-				default:
-					if err := result.p.SkipAnswer(); err != nil {
-						lastErr = &DNSError{
-							Err:    "cannot marshal DNS message",
-							Name:   name,
-							Server: result.server,
-						}
-						break loop
-					}
-					continue
-				}
-				if cname.Length == 0 && h.Name.Length != 0 {
-					cname = h.Name
-				}
-			}
-		}
-		if hitStrictError {
-			// If either family hit an error with StrictErrors enabled,
-			// discard all addresses. This ensures that network flakiness
-			// cannot turn a dualstack hostname IPv4/IPv6-only.
-			addrs = nil
-			break
-		}
-		if len(addrs) > 0 {
-			break
-		}
-	}
-	if lastErr, ok := lastErr.(*DNSError); ok {
-		// Show original name passed to lookup, not suffixed one.
-		// In general we might have tried many suffixes; showing
-		// just one is misleading. See also golang.org/issue/6324.
-		lastErr.Name = name
-	}
-	sortByRFC6724(addrs)
-	if len(addrs) == 0 {
-		if order == hostLookupDNSFiles {
-			addrs = goLookupIPFiles(name)
-		}
-		if len(addrs) == 0 && lastErr != nil {
-			return nil, dnsmessage.Name{}, lastErr
-		}
-	}
-	return addrs, cname, nil
-}
-
-// goLookupCNAME is the native Go (non-cgo) implementation of LookupCNAME.
-func (r *Resolver) goLookupCNAME(ctx context.Context, host string) (string, error) {
-	order := systemConf().hostLookupOrder(r, host)
-	_, cname, err := r.goLookupIPCNAMEOrder(ctx, "ip", host, order)
-	return cname.String(), err
-}
-
-// goLookupPTR is the native Go implementation of LookupAddr.
-// Used only if cgoLookupPTR refuses to handle the request (that is,
-// only if cgoLookupPTR is the stub in cgo_stub.go).
-// Normally we let cgo use the C library resolver instead of depending
-// on our lookup code, so that Go and C get the same answers.
-func (r *Resolver) goLookupPTR(ctx context.Context, addr string) ([]string, error) {
-	names := lookupStaticAddr(addr)
-	if len(names) > 0 {
-		return names, nil
-	}
-	arpa, err := reverseaddr(addr)
-	if err != nil {
-		return nil, err
-	}
-	p, server, err := r.lookup(ctx, arpa, dnsmessage.TypePTR)
-	if err != nil {
-		return nil, err
-	}
-	var ptrs []string
-	for {
-		h, err := p.AnswerHeader()
-		if err == dnsmessage.ErrSectionDone {
-			break
-		}
-		if err != nil {
-			return nil, &DNSError{
-				Err:    "cannot marshal DNS message",
-				Name:   addr,
-				Server: server,
-			}
-		}
-		if h.Type != dnsmessage.TypePTR {
-			err := p.SkipAnswer()
-			if err != nil {
-				return nil, &DNSError{
-					Err:    "cannot marshal DNS message",
-					Name:   addr,
-					Server: server,
-				}
-			}
-			continue
-		}
-		ptr, err := p.PTRResource()
-		if err != nil {
-			return nil, &DNSError{
-				Err:    "cannot marshal DNS message",
-				Name:   addr,
-				Server: server,
-			}
-		}
-		ptrs = append(ptrs, ptr.PTR.String())
-
-	}
-	return ptrs, nil
-}
diff --git a/contrib/go/_std_1.18/src/net/dnsconfig_unix.go b/contrib/go/_std_1.18/src/net/dnsconfig_unix.go
deleted file mode 100644
index 5ad254cd7c..0000000000
--- a/contrib/go/_std_1.18/src/net/dnsconfig_unix.go
+++ /dev/null
@@ -1,191 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
-
-// Read system DNS config from /etc/resolv.conf
-
-package net
-
-import (
-	"internal/bytealg"
-	"os"
-	"sync/atomic"
-	"time"
-)
-
-var (
-	defaultNS   = []string{"127.0.0.1:53", "[::1]:53"}
-	getHostname = os.Hostname // variable for testing
-)
-
-type dnsConfig struct {
-	servers       []string      // server addresses (in host:port form) to use
-	search        []string      // rooted suffixes to append to local name
-	ndots         int           // number of dots in name to trigger absolute lookup
-	timeout       time.Duration // wait before giving up on a query, including retries
-	attempts      int           // lost packets before giving up on server
-	rotate        bool          // round robin among servers
-	unknownOpt    bool          // anything unknown was encountered
-	lookup        []string      // OpenBSD top-level database "lookup" order
-	err           error         // any error that occurs during open of resolv.conf
-	mtime         time.Time     // time of resolv.conf modification
-	soffset       uint32        // used by serverOffset
-	singleRequest bool          // use sequential A and AAAA queries instead of parallel queries
-	useTCP        bool          // force usage of TCP for DNS resolutions
-}
-
-// See resolv.conf(5) on a Linux machine.
-func dnsReadConfig(filename string) *dnsConfig {
-	conf := &dnsConfig{
-		ndots:    1,
-		timeout:  5 * time.Second,
-		attempts: 2,
-	}
-	file, err := open(filename)
-	if err != nil {
-		conf.servers = defaultNS
-		conf.search = dnsDefaultSearch()
-		conf.err = err
-		return conf
-	}
-	defer file.close()
-	if fi, err := file.file.Stat(); err == nil {
-		conf.mtime = fi.ModTime()
-	} else {
-		conf.servers = defaultNS
-		conf.search = dnsDefaultSearch()
-		conf.err = err
-		return conf
-	}
-	for line, ok := file.readLine(); ok; line, ok = file.readLine() {
-		if len(line) > 0 && (line[0] == ';' || line[0] == '#') {
-			// comment.
-			continue
-		}
-		f := getFields(line)
-		if len(f) < 1 {
-			continue
-		}
-		switch f[0] {
-		case "nameserver": // add one name server
-			if len(f) > 1 && len(conf.servers) < 3 { // small, but the standard limit
-				// One more check: make sure server name is
-				// just an IP address. Otherwise we need DNS
-				// to look it up.
-				if parseIPv4(f[1]) != nil {
-					conf.servers = append(conf.servers, JoinHostPort(f[1], "53"))
-				} else if ip, _ := parseIPv6Zone(f[1]); ip != nil {
-					conf.servers = append(conf.servers, JoinHostPort(f[1], "53"))
-				}
-			}
-
-		case "domain": // set search path to just this domain
-			if len(f) > 1 {
-				conf.search = []string{ensureRooted(f[1])}
-			}
-
-		case "search": // set search path to given servers
-			conf.search = make([]string, len(f)-1)
-			for i := 0; i < len(conf.search); i++ {
-				conf.search[i] = ensureRooted(f[i+1])
-			}
-
-		case "options": // magic options
-			for _, s := range f[1:] {
-				switch {
-				case hasPrefix(s, "ndots:"):
-					n, _, _ := dtoi(s[6:])
-					if n < 0 {
-						n = 0
-					} else if n > 15 {
-						n = 15
-					}
-					conf.ndots = n
-				case hasPrefix(s, "timeout:"):
-					n, _, _ := dtoi(s[8:])
-					if n < 1 {
-						n = 1
-					}
-					conf.timeout = time.Duration(n) * time.Second
-				case hasPrefix(s, "attempts:"):
-					n, _, _ := dtoi(s[9:])
-					if n < 1 {
-						n = 1
-					}
-					conf.attempts = n
-				case s == "rotate":
-					conf.rotate = true
-				case s == "single-request" || s == "single-request-reopen":
-					// Linux option:
-					// http://man7.org/linux/man-pages/man5/resolv.conf.5.html
-					// "By default, glibc performs IPv4 and IPv6 lookups in parallel [...]
-					//  This option disables the behavior and makes glibc
-					//  perform the IPv6 and IPv4 requests sequentially."
-					conf.singleRequest = true
-				case s == "use-vc" || s == "usevc" || s == "tcp":
-					// Linux (use-vc), FreeBSD (usevc) and OpenBSD (tcp) option:
-					// http://man7.org/linux/man-pages/man5/resolv.conf.5.html
-					// "Sets RES_USEVC in _res.options.
-					//  This option forces the use of TCP for DNS resolutions."
-					// https://www.freebsd.org/cgi/man.cgi?query=resolv.conf&sektion=5&manpath=freebsd-release-ports
-					// https://man.openbsd.org/resolv.conf.5
-					conf.useTCP = true
-				default:
-					conf.unknownOpt = true
-				}
-			}
-
-		case "lookup":
-			// OpenBSD option:
-			// https://www.openbsd.org/cgi-bin/man.cgi/OpenBSD-current/man5/resolv.conf.5
-			// "the legal space-separated values are: bind, file, yp"
-			conf.lookup = f[1:]
-
-		default:
-			conf.unknownOpt = true
-		}
-	}
-	if len(conf.servers) == 0 {
-		conf.servers = defaultNS
-	}
-	if len(conf.search) == 0 {
-		conf.search = dnsDefaultSearch()
-	}
-	return conf
-}
-
-// serverOffset returns an offset that can be used to determine
-// indices of servers in c.servers when making queries.
-// When the rotate option is enabled, this offset increases.
-// Otherwise it is always 0.
-func (c *dnsConfig) serverOffset() uint32 {
-	if c.rotate {
-		return atomic.AddUint32(&c.soffset, 1) - 1 // return 0 to start
-	}
-	return 0
-}
-
-func dnsDefaultSearch() []string {
-	hn, err := getHostname()
-	if err != nil {
-		// best effort
-		return nil
-	}
-	if i := bytealg.IndexByteString(hn, '.'); i >= 0 && i < len(hn)-1 {
-		return []string{ensureRooted(hn[i+1:])}
-	}
-	return nil
-}
-
-func hasPrefix(s, prefix string) bool {
-	return len(s) >= len(prefix) && s[:len(prefix)] == prefix
-}
-
-func ensureRooted(s string) string {
-	if len(s) > 0 && s[len(s)-1] == '.' {
-		return s
-	}
-	return s + "."
-}
diff --git a/contrib/go/_std_1.18/src/net/error_posix.go b/contrib/go/_std_1.18/src/net/error_posix.go
deleted file mode 100644
index 10e3caa67b..0000000000
--- a/contrib/go/_std_1.18/src/net/error_posix.go
+++ /dev/null
@@ -1,21 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris || windows
-
-package net
-
-import (
-	"os"
-	"syscall"
-)
-
-// wrapSyscallError takes an error and a syscall name. If the error is
-// a syscall.Errno, it wraps it in a os.SyscallError using the syscall name.
-func wrapSyscallError(name string, err error) error {
-	if _, ok := err.(syscall.Errno); ok {
-		err = os.NewSyscallError(name, err)
-	}
-	return err
-}
diff --git a/contrib/go/_std_1.18/src/net/error_unix.go b/contrib/go/_std_1.18/src/net/error_unix.go
deleted file mode 100644
index 0e64b40ea1..0000000000
--- a/contrib/go/_std_1.18/src/net/error_unix.go
+++ /dev/null
@@ -1,16 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || js || linux || netbsd || openbsd || solaris
-
-package net
-
-import "syscall"
-
-func isConnError(err error) bool {
-	if se, ok := err.(syscall.Errno); ok {
-		return se == syscall.ECONNRESET || se == syscall.ECONNABORTED
-	}
-	return false
-}
diff --git a/contrib/go/_std_1.18/src/net/fd_posix.go b/contrib/go/_std_1.18/src/net/fd_posix.go
deleted file mode 100644
index 1845c173bb..0000000000
--- a/contrib/go/_std_1.18/src/net/fd_posix.go
+++ /dev/null
@@ -1,147 +0,0 @@
-// Copyright 2020 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris || windows
-
-package net
-
-import (
-	"internal/poll"
-	"runtime"
-	"syscall"
-	"time"
-)
-
-// Network file descriptor.
-type netFD struct {
-	pfd poll.FD
-
-	// immutable until Close
-	family      int
-	sotype      int
-	isConnected bool // handshake completed or use of association with peer
-	net         string
-	laddr       Addr
-	raddr       Addr
-}
-
-func (fd *netFD) setAddr(laddr, raddr Addr) {
-	fd.laddr = laddr
-	fd.raddr = raddr
-	runtime.SetFinalizer(fd, (*netFD).Close)
-}
-
-func (fd *netFD) Close() error {
-	runtime.SetFinalizer(fd, nil)
-	return fd.pfd.Close()
-}
-
-func (fd *netFD) shutdown(how int) error {
-	err := fd.pfd.Shutdown(how)
-	runtime.KeepAlive(fd)
-	return wrapSyscallError("shutdown", err)
-}
-
-func (fd *netFD) closeRead() error {
-	return fd.shutdown(syscall.SHUT_RD)
-}
-
-func (fd *netFD) closeWrite() error {
-	return fd.shutdown(syscall.SHUT_WR)
-}
-
-func (fd *netFD) Read(p []byte) (n int, err error) {
-	n, err = fd.pfd.Read(p)
-	runtime.KeepAlive(fd)
-	return n, wrapSyscallError(readSyscallName, err)
-}
-
-func (fd *netFD) readFrom(p []byte) (n int, sa syscall.Sockaddr, err error) {
-	n, sa, err = fd.pfd.ReadFrom(p)
-	runtime.KeepAlive(fd)
-	return n, sa, wrapSyscallError(readFromSyscallName, err)
-}
-func (fd *netFD) readFromInet4(p []byte, from *syscall.SockaddrInet4) (n int, err error) {
-	n, err = fd.pfd.ReadFromInet4(p, from)
-	runtime.KeepAlive(fd)
-	return n, wrapSyscallError(readFromSyscallName, err)
-}
-
-func (fd *netFD) readFromInet6(p []byte, from *syscall.SockaddrInet6) (n int, err error) {
-	n, err = fd.pfd.ReadFromInet6(p, from)
-	runtime.KeepAlive(fd)
-	return n, wrapSyscallError(readFromSyscallName, err)
-}
-
-func (fd *netFD) readMsg(p []byte, oob []byte, flags int) (n, oobn, retflags int, sa syscall.Sockaddr, err error) {
-	n, oobn, retflags, sa, err = fd.pfd.ReadMsg(p, oob, flags)
-	runtime.KeepAlive(fd)
-	return n, oobn, retflags, sa, wrapSyscallError(readMsgSyscallName, err)
-}
-
-func (fd *netFD) readMsgInet4(p []byte, oob []byte, flags int, sa *syscall.SockaddrInet4) (n, oobn, retflags int, err error) {
-	n, oobn, retflags, err = fd.pfd.ReadMsgInet4(p, oob, flags, sa)
-	runtime.KeepAlive(fd)
-	return n, oobn, retflags, wrapSyscallError(readMsgSyscallName, err)
-}
-
-func (fd *netFD) readMsgInet6(p []byte, oob []byte, flags int, sa *syscall.SockaddrInet6) (n, oobn, retflags int, err error) {
-	n, oobn, retflags, err = fd.pfd.ReadMsgInet6(p, oob, flags, sa)
-	runtime.KeepAlive(fd)
-	return n, oobn, retflags, wrapSyscallError(readMsgSyscallName, err)
-}
-
-func (fd *netFD) Write(p []byte) (nn int, err error) {
-	nn, err = fd.pfd.Write(p)
-	runtime.KeepAlive(fd)
-	return nn, wrapSyscallError(writeSyscallName, err)
-}
-
-func (fd *netFD) writeTo(p []byte, sa syscall.Sockaddr) (n int, err error) {
-	n, err = fd.pfd.WriteTo(p, sa)
-	runtime.KeepAlive(fd)
-	return n, wrapSyscallError(writeToSyscallName, err)
-}
-
-func (fd *netFD) writeToInet4(p []byte, sa *syscall.SockaddrInet4) (n int, err error) {
-	n, err = fd.pfd.WriteToInet4(p, sa)
-	runtime.KeepAlive(fd)
-	return n, wrapSyscallError(writeToSyscallName, err)
-}
-
-func (fd *netFD) writeToInet6(p []byte, sa *syscall.SockaddrInet6) (n int, err error) {
-	n, err = fd.pfd.WriteToInet6(p, sa)
-	runtime.KeepAlive(fd)
-	return n, wrapSyscallError(writeToSyscallName, err)
-}
-
-func (fd *netFD) writeMsg(p []byte, oob []byte, sa syscall.Sockaddr) (n int, oobn int, err error) {
-	n, oobn, err = fd.pfd.WriteMsg(p, oob, sa)
-	runtime.KeepAlive(fd)
-	return n, oobn, wrapSyscallError(writeMsgSyscallName, err)
-}
-
-func (fd *netFD) writeMsgInet4(p []byte, oob []byte, sa *syscall.SockaddrInet4) (n int, oobn int, err error) {
-	n, oobn, err = fd.pfd.WriteMsgInet4(p, oob, sa)
-	runtime.KeepAlive(fd)
-	return n, oobn, wrapSyscallError(writeMsgSyscallName, err)
-}
-
-func (fd *netFD) writeMsgInet6(p []byte, oob []byte, sa *syscall.SockaddrInet6) (n int, oobn int, err error) {
-	n, oobn, err = fd.pfd.WriteMsgInet6(p, oob, sa)
-	runtime.KeepAlive(fd)
-	return n, oobn, wrapSyscallError(writeMsgSyscallName, err)
-}
-
-func (fd *netFD) SetDeadline(t time.Time) error {
-	return fd.pfd.SetDeadline(t)
-}
-
-func (fd *netFD) SetReadDeadline(t time.Time) error {
-	return fd.pfd.SetReadDeadline(t)
-}
-
-func (fd *netFD) SetWriteDeadline(t time.Time) error {
-	return fd.pfd.SetWriteDeadline(t)
-}
diff --git a/contrib/go/_std_1.18/src/net/fd_unix.go b/contrib/go/_std_1.18/src/net/fd_unix.go
deleted file mode 100644
index aaa7a1c185..0000000000
--- a/contrib/go/_std_1.18/src/net/fd_unix.go
+++ /dev/null
@@ -1,203 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
-
-package net
-
-import (
-	"context"
-	"internal/poll"
-	"os"
-	"runtime"
-	"syscall"
-)
-
-const (
-	readSyscallName     = "read"
-	readFromSyscallName = "recvfrom"
-	readMsgSyscallName  = "recvmsg"
-	writeSyscallName    = "write"
-	writeToSyscallName  = "sendto"
-	writeMsgSyscallName = "sendmsg"
-)
-
-func newFD(sysfd, family, sotype int, net string) (*netFD, error) {
-	ret := &netFD{
-		pfd: poll.FD{
-			Sysfd:         sysfd,
-			IsStream:      sotype == syscall.SOCK_STREAM,
-			ZeroReadIsEOF: sotype != syscall.SOCK_DGRAM && sotype != syscall.SOCK_RAW,
-		},
-		family: family,
-		sotype: sotype,
-		net:    net,
-	}
-	return ret, nil
-}
-
-func (fd *netFD) init() error {
-	return fd.pfd.Init(fd.net, true)
-}
-
-func (fd *netFD) name() string {
-	var ls, rs string
-	if fd.laddr != nil {
-		ls = fd.laddr.String()
-	}
-	if fd.raddr != nil {
-		rs = fd.raddr.String()
-	}
-	return fd.net + ":" + ls + "->" + rs
-}
-
-func (fd *netFD) connect(ctx context.Context, la, ra syscall.Sockaddr) (rsa syscall.Sockaddr, ret error) {
-	// Do not need to call fd.writeLock here,
-	// because fd is not yet accessible to user,
-	// so no concurrent operations are possible.
-	switch err := connectFunc(fd.pfd.Sysfd, ra); err {
-	case syscall.EINPROGRESS, syscall.EALREADY, syscall.EINTR:
-	case nil, syscall.EISCONN:
-		select {
-		case <-ctx.Done():
-			return nil, mapErr(ctx.Err())
-		default:
-		}
-		if err := fd.pfd.Init(fd.net, true); err != nil {
-			return nil, err
-		}
-		runtime.KeepAlive(fd)
-		return nil, nil
-	case syscall.EINVAL:
-		// On Solaris and illumos we can see EINVAL if the socket has
-		// already been accepted and closed by the server.  Treat this
-		// as a successful connection--writes to the socket will see
-		// EOF.  For details and a test case in C see
-		// https://golang.org/issue/6828.
-		if runtime.GOOS == "solaris" || runtime.GOOS == "illumos" {
-			return nil, nil
-		}
-		fallthrough
-	default:
-		return nil, os.NewSyscallError("connect", err)
-	}
-	if err := fd.pfd.Init(fd.net, true); err != nil {
-		return nil, err
-	}
-	if deadline, hasDeadline := ctx.Deadline(); hasDeadline {
-		fd.pfd.SetWriteDeadline(deadline)
-		defer fd.pfd.SetWriteDeadline(noDeadline)
-	}
-
-	// Start the "interrupter" goroutine, if this context might be canceled.
-	//
-	// The interrupter goroutine waits for the context to be done and
-	// interrupts the dial (by altering the fd's write deadline, which
-	// wakes up waitWrite).
-	ctxDone := ctx.Done()
-	if ctxDone != nil {
-		// Wait for the interrupter goroutine to exit before returning
-		// from connect.
-		done := make(chan struct{})
-		interruptRes := make(chan error)
-		defer func() {
-			close(done)
-			if ctxErr := <-interruptRes; ctxErr != nil && ret == nil {
-				// The interrupter goroutine called SetWriteDeadline,
-				// but the connect code below had returned from
-				// waitWrite already and did a successful connect (ret
-				// == nil). Because we've now poisoned the connection
-				// by making it unwritable, don't return a successful
-				// dial. This was issue 16523.
-				ret = mapErr(ctxErr)
-				fd.Close() // prevent a leak
-			}
-		}()
-		go func() {
-			select {
-			case <-ctxDone:
-				// Force the runtime's poller to immediately give up
-				// waiting for writability, unblocking waitWrite
-				// below.
-				fd.pfd.SetWriteDeadline(aLongTimeAgo)
-				testHookCanceledDial()
-				interruptRes <- ctx.Err()
-			case <-done:
-				interruptRes <- nil
-			}
-		}()
-	}
-
-	for {
-		// Performing multiple connect system calls on a
-		// non-blocking socket under Unix variants does not
-		// necessarily result in earlier errors being
-		// returned. Instead, once runtime-integrated network
-		// poller tells us that the socket is ready, get the
-		// SO_ERROR socket option to see if the connection
-		// succeeded or failed. See issue 7474 for further
-		// details.
-		if err := fd.pfd.WaitWrite(); err != nil {
-			select {
-			case <-ctxDone:
-				return nil, mapErr(ctx.Err())
-			default:
-			}
-			return nil, err
-		}
-		nerr, err := getsockoptIntFunc(fd.pfd.Sysfd, syscall.SOL_SOCKET, syscall.SO_ERROR)
-		if err != nil {
-			return nil, os.NewSyscallError("getsockopt", err)
-		}
-		switch err := syscall.Errno(nerr); err {
-		case syscall.EINPROGRESS, syscall.EALREADY, syscall.EINTR:
-		case syscall.EISCONN:
-			return nil, nil
-		case syscall.Errno(0):
-			// The runtime poller can wake us up spuriously;
-			// see issues 14548 and 19289. Check that we are
-			// really connected; if not, wait again.
-			if rsa, err := syscall.Getpeername(fd.pfd.Sysfd); err == nil {
-				return rsa, nil
-			}
-		default:
-			return nil, os.NewSyscallError("connect", err)
-		}
-		runtime.KeepAlive(fd)
-	}
-}
-
-func (fd *netFD) accept() (netfd *netFD, err error) {
-	d, rsa, errcall, err := fd.pfd.Accept()
-	if err != nil {
-		if errcall != "" {
-			err = wrapSyscallError(errcall, err)
-		}
-		return nil, err
-	}
-
-	if netfd, err = newFD(d, fd.family, fd.sotype, fd.net); err != nil {
-		poll.CloseFunc(d)
-		return nil, err
-	}
-	if err = netfd.init(); err != nil {
-		netfd.Close()
-		return nil, err
-	}
-	lsa, _ := syscall.Getsockname(netfd.pfd.Sysfd)
-	netfd.setAddr(netfd.addrFunc()(lsa), netfd.addrFunc()(rsa))
-	return netfd, nil
-}
-
-func (fd *netFD) dup() (f *os.File, err error) {
-	ns, call, err := fd.pfd.Dup()
-	if err != nil {
-		if call != "" {
-			err = os.NewSyscallError(call, err)
-		}
-		return nil, err
-	}
-
-	return os.NewFile(uintptr(ns), fd.name()), nil
-}
diff --git a/contrib/go/_std_1.18/src/net/file_unix.go b/contrib/go/_std_1.18/src/net/file_unix.go
deleted file mode 100644
index 68d7eb9ca0..0000000000
--- a/contrib/go/_std_1.18/src/net/file_unix.go
+++ /dev/null
@@ -1,119 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
-
-package net
-
-import (
-	"internal/poll"
-	"os"
-	"syscall"
-)
-
-func dupSocket(f *os.File) (int, error) {
-	s, call, err := poll.DupCloseOnExec(int(f.Fd()))
-	if err != nil {
-		if call != "" {
-			err = os.NewSyscallError(call, err)
-		}
-		return -1, err
-	}
-	if err := syscall.SetNonblock(s, true); err != nil {
-		poll.CloseFunc(s)
-		return -1, os.NewSyscallError("setnonblock", err)
-	}
-	return s, nil
-}
-
-func newFileFD(f *os.File) (*netFD, error) {
-	s, err := dupSocket(f)
-	if err != nil {
-		return nil, err
-	}
-	family := syscall.AF_UNSPEC
-	sotype, err := syscall.GetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_TYPE)
-	if err != nil {
-		poll.CloseFunc(s)
-		return nil, os.NewSyscallError("getsockopt", err)
-	}
-	lsa, _ := syscall.Getsockname(s)
-	rsa, _ := syscall.Getpeername(s)
-	switch lsa.(type) {
-	case *syscall.SockaddrInet4:
-		family = syscall.AF_INET
-	case *syscall.SockaddrInet6:
-		family = syscall.AF_INET6
-	case *syscall.SockaddrUnix:
-		family = syscall.AF_UNIX
-	default:
-		poll.CloseFunc(s)
-		return nil, syscall.EPROTONOSUPPORT
-	}
-	fd, err := newFD(s, family, sotype, "")
-	if err != nil {
-		poll.CloseFunc(s)
-		return nil, err
-	}
-	laddr := fd.addrFunc()(lsa)
-	raddr := fd.addrFunc()(rsa)
-	fd.net = laddr.Network()
-	if err := fd.init(); err != nil {
-		fd.Close()
-		return nil, err
-	}
-	fd.setAddr(laddr, raddr)
-	return fd, nil
-}
-
-func fileConn(f *os.File) (Conn, error) {
-	fd, err := newFileFD(f)
-	if err != nil {
-		return nil, err
-	}
-	switch fd.laddr.(type) {
-	case *TCPAddr:
-		return newTCPConn(fd), nil
-	case *UDPAddr:
-		return newUDPConn(fd), nil
-	case *IPAddr:
-		return newIPConn(fd), nil
-	case *UnixAddr:
-		return newUnixConn(fd), nil
-	}
-	fd.Close()
-	return nil, syscall.EINVAL
-}
-
-func fileListener(f *os.File) (Listener, error) {
-	fd, err := newFileFD(f)
-	if err != nil {
-		return nil, err
-	}
-	switch laddr := fd.laddr.(type) {
-	case *TCPAddr:
-		return &TCPListener{fd: fd}, nil
-	case *UnixAddr:
-		return &UnixListener{fd: fd, path: laddr.Name, unlink: false}, nil
-	}
-	fd.Close()
-	return nil, syscall.EINVAL
-}
-
-func filePacketConn(f *os.File) (PacketConn, error) {
-	fd, err := newFileFD(f)
-	if err != nil {
-		return nil, err
-	}
-	switch fd.laddr.(type) {
-	case *UDPAddr:
-		return newUDPConn(fd), nil
-	case *IPAddr:
-		return newIPConn(fd), nil
-	case *UnixAddr:
-		return newUnixConn(fd), nil
-	}
-	fd.Close()
-	return nil, syscall.EINVAL
-}
diff --git a/contrib/go/_std_1.18/src/net/hook_unix.go b/contrib/go/_std_1.18/src/net/hook_unix.go
deleted file mode 100644
index 7c36b0d6e3..0000000000
--- a/contrib/go/_std_1.18/src/net/hook_unix.go
+++ /dev/null
@@ -1,20 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris
-
-package net
-
-import "syscall"
-
-var (
-	testHookDialChannel  = func() {} // for golang.org/issue/5349
-	testHookCanceledDial = func() {} // for golang.org/issue/16523
-
-	// Placeholders for socket system calls.
-	socketFunc        func(int, int, int) (int, error)  = syscall.Socket
-	connectFunc       func(int, syscall.Sockaddr) error = syscall.Connect
-	listenFunc        func(int, int) error              = syscall.Listen
-	getsockoptIntFunc func(int, int, int) (int, error)  = syscall.GetsockoptInt
-)
diff --git a/contrib/go/_std_1.18/src/net/http/client.go b/contrib/go/_std_1.18/src/net/http/client.go
deleted file mode 100644
index 22db96b267..0000000000
--- a/contrib/go/_std_1.18/src/net/http/client.go
+++ /dev/null
@@ -1,1033 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// HTTP client. See RFC 7230 through 7235.
-//
-// This is the high-level Client interface.
-// The low-level implementation is in transport.go.
-
-package http
-
-import (
-	"context"
-	"crypto/tls"
-	"encoding/base64"
-	"errors"
-	"fmt"
-	"io"
-	"log"
-	"net/http/internal/ascii"
-	"net/url"
-	"reflect"
-	"sort"
-	"strings"
-	"sync"
-	"time"
-)
-
-// A Client is an HTTP client. Its zero value (DefaultClient) is a
-// usable client that uses DefaultTransport.
-//
-// The Client's Transport typically has internal state (cached TCP
-// connections), so Clients should be reused instead of created as
-// needed. Clients are safe for concurrent use by multiple goroutines.
-//
-// A Client is higher-level than a RoundTripper (such as Transport)
-// and additionally handles HTTP details such as cookies and
-// redirects.
-//
-// When following redirects, the Client will forward all headers set on the
-// initial Request except:
-//
-// • when forwarding sensitive headers like "Authorization",
-// "WWW-Authenticate", and "Cookie" to untrusted targets.
-// These headers will be ignored when following a redirect to a domain
-// that is not a subdomain match or exact match of the initial domain.
-// For example, a redirect from "foo.com" to either "foo.com" or "sub.foo.com"
-// will forward the sensitive headers, but a redirect to "bar.com" will not.
-//
-// • when forwarding the "Cookie" header with a non-nil cookie Jar.
-// Since each redirect may mutate the state of the cookie jar,
-// a redirect may possibly alter a cookie set in the initial request.
-// When forwarding the "Cookie" header, any mutated cookies will be omitted,
-// with the expectation that the Jar will insert those mutated cookies
-// with the updated values (assuming the origin matches).
-// If Jar is nil, the initial cookies are forwarded without change.
-//
-type Client struct {
-	// Transport specifies the mechanism by which individual
-	// HTTP requests are made.
-	// If nil, DefaultTransport is used.
-	Transport RoundTripper
-
-	// CheckRedirect specifies the policy for handling redirects.
-	// If CheckRedirect is not nil, the client calls it before
-	// following an HTTP redirect. The arguments req and via are
-	// the upcoming request and the requests made already, oldest
-	// first. If CheckRedirect returns an error, the Client's Get
-	// method returns both the previous Response (with its Body
-	// closed) and CheckRedirect's error (wrapped in a url.Error)
-	// instead of issuing the Request req.
-	// As a special case, if CheckRedirect returns ErrUseLastResponse,
-	// then the most recent response is returned with its body
-	// unclosed, along with a nil error.
-	//
-	// If CheckRedirect is nil, the Client uses its default policy,
-	// which is to stop after 10 consecutive requests.
-	CheckRedirect func(req *Request, via []*Request) error
-
-	// Jar specifies the cookie jar.
-	//
-	// The Jar is used to insert relevant cookies into every
-	// outbound Request and is updated with the cookie values
-	// of every inbound Response. The Jar is consulted for every
-	// redirect that the Client follows.
-	//
-	// If Jar is nil, cookies are only sent if they are explicitly
-	// set on the Request.
-	Jar CookieJar
-
-	// Timeout specifies a time limit for requests made by this
-	// Client. The timeout includes connection time, any
-	// redirects, and reading the response body. The timer remains
-	// running after Get, Head, Post, or Do return and will
-	// interrupt reading of the Response.Body.
-	//
-	// A Timeout of zero means no timeout.
-	//
-	// The Client cancels requests to the underlying Transport
-	// as if the Request's Context ended.
-	//
-	// For compatibility, the Client will also use the deprecated
-	// CancelRequest method on Transport if found. New
-	// RoundTripper implementations should use the Request's Context
-	// for cancellation instead of implementing CancelRequest.
-	Timeout time.Duration
-}
-
-// DefaultClient is the default Client and is used by Get, Head, and Post.
-var DefaultClient = &Client{}
-
-// RoundTripper is an interface representing the ability to execute a
-// single HTTP transaction, obtaining the Response for a given Request.
-//
-// A RoundTripper must be safe for concurrent use by multiple
-// goroutines.
-type RoundTripper interface {
-	// RoundTrip executes a single HTTP transaction, returning
-	// a Response for the provided Request.
-	//
-	// RoundTrip should not attempt to interpret the response. In
-	// particular, RoundTrip must return err == nil if it obtained
-	// a response, regardless of the response's HTTP status code.
-	// A non-nil err should be reserved for failure to obtain a
-	// response. Similarly, RoundTrip should not attempt to
-	// handle higher-level protocol details such as redirects,
-	// authentication, or cookies.
-	//
-	// RoundTrip should not modify the request, except for
-	// consuming and closing the Request's Body. RoundTrip may
-	// read fields of the request in a separate goroutine. Callers
-	// should not mutate or reuse the request until the Response's
-	// Body has been closed.
-	//
-	// RoundTrip must always close the body, including on errors,
-	// but depending on the implementation may do so in a separate
-	// goroutine even after RoundTrip returns. This means that
-	// callers wanting to reuse the body for subsequent requests
-	// must arrange to wait for the Close call before doing so.
-	//
-	// The Request's URL and Header fields must be initialized.
-	RoundTrip(*Request) (*Response, error)
-}
-
-// refererForURL returns a referer without any authentication info or
-// an empty string if lastReq scheme is https and newReq scheme is http.
-func refererForURL(lastReq, newReq *url.URL) string {
-	// https://tools.ietf.org/html/rfc7231#section-5.5.2
-	//   "Clients SHOULD NOT include a Referer header field in a
-	//    (non-secure) HTTP request if the referring page was
-	//    transferred with a secure protocol."
-	if lastReq.Scheme == "https" && newReq.Scheme == "http" {
-		return ""
-	}
-	referer := lastReq.String()
-	if lastReq.User != nil {
-		// This is not very efficient, but is the best we can
-		// do without:
-		// - introducing a new method on URL
-		// - creating a race condition
-		// - copying the URL struct manually, which would cause
-		//   maintenance problems down the line
-		auth := lastReq.User.String() + "@"
-		referer = strings.Replace(referer, auth, "", 1)
-	}
-	return referer
-}
-
-// didTimeout is non-nil only if err != nil.
-func (c *Client) send(req *Request, deadline time.Time) (resp *Response, didTimeout func() bool, err error) {
-	if c.Jar != nil {
-		for _, cookie := range c.Jar.Cookies(req.URL) {
-			req.AddCookie(cookie)
-		}
-	}
-	resp, didTimeout, err = send(req, c.transport(), deadline)
-	if err != nil {
-		return nil, didTimeout, err
-	}
-	if c.Jar != nil {
-		if rc := resp.Cookies(); len(rc) > 0 {
-			c.Jar.SetCookies(req.URL, rc)
-		}
-	}
-	return resp, nil, nil
-}
-
-func (c *Client) deadline() time.Time {
-	if c.Timeout > 0 {
-		return time.Now().Add(c.Timeout)
-	}
-	return time.Time{}
-}
-
-func (c *Client) transport() RoundTripper {
-	if c.Transport != nil {
-		return c.Transport
-	}
-	return DefaultTransport
-}
-
-// send issues an HTTP request.
-// Caller should close resp.Body when done reading from it.
-func send(ireq *Request, rt RoundTripper, deadline time.Time) (resp *Response, didTimeout func() bool, err error) {
-	req := ireq // req is either the original request, or a modified fork
-
-	if rt == nil {
-		req.closeBody()
-		return nil, alwaysFalse, errors.New("http: no Client.Transport or DefaultTransport")
-	}
-
-	if req.URL == nil {
-		req.closeBody()
-		return nil, alwaysFalse, errors.New("http: nil Request.URL")
-	}
-
-	if req.RequestURI != "" {
-		req.closeBody()
-		return nil, alwaysFalse, errors.New("http: Request.RequestURI can't be set in client requests")
-	}
-
-	// forkReq forks req into a shallow clone of ireq the first
-	// time it's called.
-	forkReq := func() {
-		if ireq == req {
-			req = new(Request)
-			*req = *ireq // shallow clone
-		}
-	}
-
-	// Most the callers of send (Get, Post, et al) don't need
-	// Headers, leaving it uninitialized. We guarantee to the
-	// Transport that this has been initialized, though.
-	if req.Header == nil {
-		forkReq()
-		req.Header = make(Header)
-	}
-
-	if u := req.URL.User; u != nil && req.Header.Get("Authorization") == "" {
-		username := u.Username()
-		password, _ := u.Password()
-		forkReq()
-		req.Header = cloneOrMakeHeader(ireq.Header)
-		req.Header.Set("Authorization", "Basic "+basicAuth(username, password))
-	}
-
-	if !deadline.IsZero() {
-		forkReq()
-	}
-	stopTimer, didTimeout := setRequestCancel(req, rt, deadline)
-
-	resp, err = rt.RoundTrip(req)
-	if err != nil {
-		stopTimer()
-		if resp != nil {
-			log.Printf("RoundTripper returned a response & error; ignoring response")
-		}
-		if tlsErr, ok := err.(tls.RecordHeaderError); ok {
-			// If we get a bad TLS record header, check to see if the
-			// response looks like HTTP and give a more helpful error.
-			// See golang.org/issue/11111.
-			if string(tlsErr.RecordHeader[:]) == "HTTP/" {
-				err = errors.New("http: server gave HTTP response to HTTPS client")
-			}
-		}
-		return nil, didTimeout, err
-	}
-	if resp == nil {
-		return nil, didTimeout, fmt.Errorf("http: RoundTripper implementation (%T) returned a nil *Response with a nil error", rt)
-	}
-	if resp.Body == nil {
-		// The documentation on the Body field says “The http Client and Transport
-		// guarantee that Body is always non-nil, even on responses without a body
-		// or responses with a zero-length body.” Unfortunately, we didn't document
-		// that same constraint for arbitrary RoundTripper implementations, and
-		// RoundTripper implementations in the wild (mostly in tests) assume that
-		// they can use a nil Body to mean an empty one (similar to Request.Body).
-		// (See https://golang.org/issue/38095.)
-		//
-		// If the ContentLength allows the Body to be empty, fill in an empty one
-		// here to ensure that it is non-nil.
-		if resp.ContentLength > 0 && req.Method != "HEAD" {
-			return nil, didTimeout, fmt.Errorf("http: RoundTripper implementation (%T) returned a *Response with content length %d but a nil Body", rt, resp.ContentLength)
-		}
-		resp.Body = io.NopCloser(strings.NewReader(""))
-	}
-	if !deadline.IsZero() {
-		resp.Body = &cancelTimerBody{
-			stop:          stopTimer,
-			rc:            resp.Body,
-			reqDidTimeout: didTimeout,
-		}
-	}
-	return resp, nil, nil
-}
-
-// timeBeforeContextDeadline reports whether the non-zero Time t is
-// before ctx's deadline, if any. If ctx does not have a deadline, it
-// always reports true (the deadline is considered infinite).
-func timeBeforeContextDeadline(t time.Time, ctx context.Context) bool {
-	d, ok := ctx.Deadline()
-	if !ok {
-		return true
-	}
-	return t.Before(d)
-}
-
-// knownRoundTripperImpl reports whether rt is a RoundTripper that's
-// maintained by the Go team and known to implement the latest
-// optional semantics (notably contexts). The Request is used
-// to check whether this particular request is using an alternate protocol,
-// in which case we need to check the RoundTripper for that protocol.
-func knownRoundTripperImpl(rt RoundTripper, req *Request) bool {
-	switch t := rt.(type) {
-	case *Transport:
-		if altRT := t.alternateRoundTripper(req); altRT != nil {
-			return knownRoundTripperImpl(altRT, req)
-		}
-		return true
-	case *http2Transport, http2noDialH2RoundTripper:
-		return true
-	}
-	// There's a very minor chance of a false positive with this.
-	// Instead of detecting our golang.org/x/net/http2.Transport,
-	// it might detect a Transport type in a different http2
-	// package. But I know of none, and the only problem would be
-	// some temporarily leaked goroutines if the transport didn't
-	// support contexts. So this is a good enough heuristic:
-	if reflect.TypeOf(rt).String() == "*http2.Transport" {
-		return true
-	}
-	return false
-}
-
-// setRequestCancel sets req.Cancel and adds a deadline context to req
-// if deadline is non-zero. The RoundTripper's type is used to
-// determine whether the legacy CancelRequest behavior should be used.
-//
-// As background, there are three ways to cancel a request:
-// First was Transport.CancelRequest. (deprecated)
-// Second was Request.Cancel.
-// Third was Request.Context.
-// This function populates the second and third, and uses the first if it really needs to.
-func setRequestCancel(req *Request, rt RoundTripper, deadline time.Time) (stopTimer func(), didTimeout func() bool) {
-	if deadline.IsZero() {
-		return nop, alwaysFalse
-	}
-	knownTransport := knownRoundTripperImpl(rt, req)
-	oldCtx := req.Context()
-
-	if req.Cancel == nil && knownTransport {
-		// If they already had a Request.Context that's
-		// expiring sooner, do nothing:
-		if !timeBeforeContextDeadline(deadline, oldCtx) {
-			return nop, alwaysFalse
-		}
-
-		var cancelCtx func()
-		req.ctx, cancelCtx = context.WithDeadline(oldCtx, deadline)
-		return cancelCtx, func() bool { return time.Now().After(deadline) }
-	}
-	initialReqCancel := req.Cancel // the user's original Request.Cancel, if any
-
-	var cancelCtx func()
-	if oldCtx := req.Context(); timeBeforeContextDeadline(deadline, oldCtx) {
-		req.ctx, cancelCtx = context.WithDeadline(oldCtx, deadline)
-	}
-
-	cancel := make(chan struct{})
-	req.Cancel = cancel
-
-	doCancel := func() {
-		// The second way in the func comment above:
-		close(cancel)
-		// The first way, used only for RoundTripper
-		// implementations written before Go 1.5 or Go 1.6.
-		type canceler interface{ CancelRequest(*Request) }
-		if v, ok := rt.(canceler); ok {
-			v.CancelRequest(req)
-		}
-	}
-
-	stopTimerCh := make(chan struct{})
-	var once sync.Once
-	stopTimer = func() {
-		once.Do(func() {
-			close(stopTimerCh)
-			if cancelCtx != nil {
-				cancelCtx()
-			}
-		})
-	}
-
-	timer := time.NewTimer(time.Until(deadline))
-	var timedOut atomicBool
-
-	go func() {
-		select {
-		case <-initialReqCancel:
-			doCancel()
-			timer.Stop()
-		case <-timer.C:
-			timedOut.setTrue()
-			doCancel()
-		case <-stopTimerCh:
-			timer.Stop()
-		}
-	}()
-
-	return stopTimer, timedOut.isSet
-}
-
-// See 2 (end of page 4) https://www.ietf.org/rfc/rfc2617.txt
-// "To receive authorization, the client sends the userid and password,
-// separated by a single colon (":") character, within a base64
-// encoded string in the credentials."
-// It is not meant to be urlencoded.
-func basicAuth(username, password string) string {
-	auth := username + ":" + password
-	return base64.StdEncoding.EncodeToString([]byte(auth))
-}
-
-// Get issues a GET to the specified URL. If the response is one of
-// the following redirect codes, Get follows the redirect, up to a
-// maximum of 10 redirects:
-//
-//    301 (Moved Permanently)
-//    302 (Found)
-//    303 (See Other)
-//    307 (Temporary Redirect)
-//    308 (Permanent Redirect)
-//
-// An error is returned if there were too many redirects or if there
-// was an HTTP protocol error. A non-2xx response doesn't cause an
-// error. Any returned error will be of type *url.Error. The url.Error
-// value's Timeout method will report true if the request timed out.
-//
-// When err is nil, resp always contains a non-nil resp.Body.
-// Caller should close resp.Body when done reading from it.
-//
-// Get is a wrapper around DefaultClient.Get.
-//
-// To make a request with custom headers, use NewRequest and
-// DefaultClient.Do.
-//
-// To make a request with a specified context.Context, use NewRequestWithContext
-// and DefaultClient.Do.
-func Get(url string) (resp *Response, err error) {
-	return DefaultClient.Get(url)
-}
-
-// Get issues a GET to the specified URL. If the response is one of the
-// following redirect codes, Get follows the redirect after calling the
-// Client's CheckRedirect function:
-//
-//    301 (Moved Permanently)
-//    302 (Found)
-//    303 (See Other)
-//    307 (Temporary Redirect)
-//    308 (Permanent Redirect)
-//
-// An error is returned if the Client's CheckRedirect function fails
-// or if there was an HTTP protocol error. A non-2xx response doesn't
-// cause an error. Any returned error will be of type *url.Error. The
-// url.Error value's Timeout method will report true if the request
-// timed out.
-//
-// When err is nil, resp always contains a non-nil resp.Body.
-// Caller should close resp.Body when done reading from it.
-//
-// To make a request with custom headers, use NewRequest and Client.Do.
-//
-// To make a request with a specified context.Context, use NewRequestWithContext
-// and Client.Do.
-func (c *Client) Get(url string) (resp *Response, err error) {
-	req, err := NewRequest("GET", url, nil)
-	if err != nil {
-		return nil, err
-	}
-	return c.Do(req)
-}
-
-func alwaysFalse() bool { return false }
-
-// ErrUseLastResponse can be returned by Client.CheckRedirect hooks to
-// control how redirects are processed. If returned, the next request
-// is not sent and the most recent response is returned with its body
-// unclosed.
-var ErrUseLastResponse = errors.New("net/http: use last response")
-
-// checkRedirect calls either the user's configured CheckRedirect
-// function, or the default.
-func (c *Client) checkRedirect(req *Request, via []*Request) error {
-	fn := c.CheckRedirect
-	if fn == nil {
-		fn = defaultCheckRedirect
-	}
-	return fn(req, via)
-}
-
-// redirectBehavior describes what should happen when the
-// client encounters a 3xx status code from the server
-func redirectBehavior(reqMethod string, resp *Response, ireq *Request) (redirectMethod string, shouldRedirect, includeBody bool) {
-	switch resp.StatusCode {
-	case 301, 302, 303:
-		redirectMethod = reqMethod
-		shouldRedirect = true
-		includeBody = false
-
-		// RFC 2616 allowed automatic redirection only with GET and
-		// HEAD requests. RFC 7231 lifts this restriction, but we still
-		// restrict other methods to GET to maintain compatibility.
-		// See Issue 18570.
-		if reqMethod != "GET" && reqMethod != "HEAD" {
-			redirectMethod = "GET"
-		}
-	case 307, 308:
-		redirectMethod = reqMethod
-		shouldRedirect = true
-		includeBody = true
-
-		// Treat 307 and 308 specially, since they're new in
-		// Go 1.8, and they also require re-sending the request body.
-		if resp.Header.Get("Location") == "" {
-			// 308s have been observed in the wild being served
-			// without Location headers. Since Go 1.7 and earlier
-			// didn't follow these codes, just stop here instead
-			// of returning an error.
-			// See Issue 17773.
-			shouldRedirect = false
-			break
-		}
-		if ireq.GetBody == nil && ireq.outgoingLength() != 0 {
-			// We had a request body, and 307/308 require
-			// re-sending it, but GetBody is not defined. So just
-			// return this response to the user instead of an
-			// error, like we did in Go 1.7 and earlier.
-			shouldRedirect = false
-		}
-	}
-	return redirectMethod, shouldRedirect, includeBody
-}
-
-// urlErrorOp returns the (*url.Error).Op value to use for the
-// provided (*Request).Method value.
-func urlErrorOp(method string) string {
-	if method == "" {
-		return "Get"
-	}
-	if lowerMethod, ok := ascii.ToLower(method); ok {
-		return method[:1] + lowerMethod[1:]
-	}
-	return method
-}
-
-// Do sends an HTTP request and returns an HTTP response, following
-// policy (such as redirects, cookies, auth) as configured on the
-// client.
-//
-// An error is returned if caused by client policy (such as
-// CheckRedirect), or failure to speak HTTP (such as a network
-// connectivity problem). A non-2xx status code doesn't cause an
-// error.
-//
-// If the returned error is nil, the Response will contain a non-nil
-// Body which the user is expected to close. If the Body is not both
-// read to EOF and closed, the Client's underlying RoundTripper
-// (typically Transport) may not be able to re-use a persistent TCP
-// connection to the server for a subsequent "keep-alive" request.
-//
-// The request Body, if non-nil, will be closed by the underlying
-// Transport, even on errors.
-//
-// On error, any Response can be ignored. A non-nil Response with a
-// non-nil error only occurs when CheckRedirect fails, and even then
-// the returned Response.Body is already closed.
-//
-// Generally Get, Post, or PostForm will be used instead of Do.
-//
-// If the server replies with a redirect, the Client first uses the
-// CheckRedirect function to determine whether the redirect should be
-// followed. If permitted, a 301, 302, or 303 redirect causes
-// subsequent requests to use HTTP method GET
-// (or HEAD if the original request was HEAD), with no body.
-// A 307 or 308 redirect preserves the original HTTP method and body,
-// provided that the Request.GetBody function is defined.
-// The NewRequest function automatically sets GetBody for common
-// standard library body types.
-//
-// Any returned error will be of type *url.Error. The url.Error
-// value's Timeout method will report true if the request timed out.
-func (c *Client) Do(req *Request) (*Response, error) {
-	return c.do(req)
-}
-
-var testHookClientDoResult func(retres *Response, reterr error)
-
-func (c *Client) do(req *Request) (retres *Response, reterr error) {
-	if testHookClientDoResult != nil {
-		defer func() { testHookClientDoResult(retres, reterr) }()
-	}
-	if req.URL == nil {
-		req.closeBody()
-		return nil, &url.Error{
-			Op:  urlErrorOp(req.Method),
-			Err: errors.New("http: nil Request.URL"),
-		}
-	}
-
-	var (
-		deadline      = c.deadline()
-		reqs          []*Request
-		resp          *Response
-		copyHeaders   = c.makeHeadersCopier(req)
-		reqBodyClosed = false // have we closed the current req.Body?
-
-		// Redirect behavior:
-		redirectMethod string
-		includeBody    bool
-	)
-	uerr := func(err error) error {
-		// the body may have been closed already by c.send()
-		if !reqBodyClosed {
-			req.closeBody()
-		}
-		var urlStr string
-		if resp != nil && resp.Request != nil {
-			urlStr = stripPassword(resp.Request.URL)
-		} else {
-			urlStr = stripPassword(req.URL)
-		}
-		return &url.Error{
-			Op:  urlErrorOp(reqs[0].Method),
-			URL: urlStr,
-			Err: err,
-		}
-	}
-	for {
-		// For all but the first request, create the next
-		// request hop and replace req.
-		if len(reqs) > 0 {
-			loc := resp.Header.Get("Location")
-			if loc == "" {
-				resp.closeBody()
-				return nil, uerr(fmt.Errorf("%d response missing Location header", resp.StatusCode))
-			}
-			u, err := req.URL.Parse(loc)
-			if err != nil {
-				resp.closeBody()
-				return nil, uerr(fmt.Errorf("failed to parse Location header %q: %v", loc, err))
-			}
-			host := ""
-			if req.Host != "" && req.Host != req.URL.Host {
-				// If the caller specified a custom Host header and the
-				// redirect location is relative, preserve the Host header
-				// through the redirect. See issue #22233.
-				if u, _ := url.Parse(loc); u != nil && !u.IsAbs() {
-					host = req.Host
-				}
-			}
-			ireq := reqs[0]
-			req = &Request{
-				Method:   redirectMethod,
-				Response: resp,
-				URL:      u,
-				Header:   make(Header),
-				Host:     host,
-				Cancel:   ireq.Cancel,
-				ctx:      ireq.ctx,
-			}
-			if includeBody && ireq.GetBody != nil {
-				req.Body, err = ireq.GetBody()
-				if err != nil {
-					resp.closeBody()
-					return nil, uerr(err)
-				}
-				req.ContentLength = ireq.ContentLength
-			}
-
-			// Copy original headers before setting the Referer,
-			// in case the user set Referer on their first request.
-			// If they really want to override, they can do it in
-			// their CheckRedirect func.
-			copyHeaders(req)
-
-			// Add the Referer header from the most recent
-			// request URL to the new one, if it's not https->http:
-			if ref := refererForURL(reqs[len(reqs)-1].URL, req.URL); ref != "" {
-				req.Header.Set("Referer", ref)
-			}
-			err = c.checkRedirect(req, reqs)
-
-			// Sentinel error to let users select the
-			// previous response, without closing its
-			// body. See Issue 10069.
-			if err == ErrUseLastResponse {
-				return resp, nil
-			}
-
-			// Close the previous response's body. But
-			// read at least some of the body so if it's
-			// small the underlying TCP connection will be
-			// re-used. No need to check for errors: if it
-			// fails, the Transport won't reuse it anyway.
-			const maxBodySlurpSize = 2 << 10
-			if resp.ContentLength == -1 || resp.ContentLength <= maxBodySlurpSize {
-				io.CopyN(io.Discard, resp.Body, maxBodySlurpSize)
-			}
-			resp.Body.Close()
-
-			if err != nil {
-				// Special case for Go 1 compatibility: return both the response
-				// and an error if the CheckRedirect function failed.
-				// See https://golang.org/issue/3795
-				// The resp.Body has already been closed.
-				ue := uerr(err)
-				ue.(*url.Error).URL = loc
-				return resp, ue
-			}
-		}
-
-		reqs = append(reqs, req)
-		var err error
-		var didTimeout func() bool
-		if resp, didTimeout, err = c.send(req, deadline); err != nil {
-			// c.send() always closes req.Body
-			reqBodyClosed = true
-			if !deadline.IsZero() && didTimeout() {
-				err = &httpError{
-					err:     err.Error() + " (Client.Timeout exceeded while awaiting headers)",
-					timeout: true,
-				}
-			}
-			return nil, uerr(err)
-		}
-
-		var shouldRedirect bool
-		redirectMethod, shouldRedirect, includeBody = redirectBehavior(req.Method, resp, reqs[0])
-		if !shouldRedirect {
-			return resp, nil
-		}
-
-		req.closeBody()
-	}
-}
-
-// makeHeadersCopier makes a function that copies headers from the
-// initial Request, ireq. For every redirect, this function must be called
-// so that it can copy headers into the upcoming Request.
-func (c *Client) makeHeadersCopier(ireq *Request) func(*Request) {
-	// The headers to copy are from the very initial request.
-	// We use a closured callback to keep a reference to these original headers.
-	var (
-		ireqhdr  = cloneOrMakeHeader(ireq.Header)
-		icookies map[string][]*Cookie
-	)
-	if c.Jar != nil && ireq.Header.Get("Cookie") != "" {
-		icookies = make(map[string][]*Cookie)
-		for _, c := range ireq.Cookies() {
-			icookies[c.Name] = append(icookies[c.Name], c)
-		}
-	}
-
-	preq := ireq // The previous request
-	return func(req *Request) {
-		// If Jar is present and there was some initial cookies provided
-		// via the request header, then we may need to alter the initial
-		// cookies as we follow redirects since each redirect may end up
-		// modifying a pre-existing cookie.
-		//
-		// Since cookies already set in the request header do not contain
-		// information about the original domain and path, the logic below
-		// assumes any new set cookies override the original cookie
-		// regardless of domain or path.
-		//
-		// See https://golang.org/issue/17494
-		if c.Jar != nil && icookies != nil {
-			var changed bool
-			resp := req.Response // The response that caused the upcoming redirect
-			for _, c := range resp.Cookies() {
-				if _, ok := icookies[c.Name]; ok {
-					delete(icookies, c.Name)
-					changed = true
-				}
-			}
-			if changed {
-				ireqhdr.Del("Cookie")
-				var ss []string
-				for _, cs := range icookies {
-					for _, c := range cs {
-						ss = append(ss, c.Name+"="+c.Value)
-					}
-				}
-				sort.Strings(ss) // Ensure deterministic headers
-				ireqhdr.Set("Cookie", strings.Join(ss, "; "))
-			}
-		}
-
-		// Copy the initial request's Header values
-		// (at least the safe ones).
-		for k, vv := range ireqhdr {
-			if shouldCopyHeaderOnRedirect(k, preq.URL, req.URL) {
-				req.Header[k] = vv
-			}
-		}
-
-		preq = req // Update previous Request with the current request
-	}
-}
-
-func defaultCheckRedirect(req *Request, via []*Request) error {
-	if len(via) >= 10 {
-		return errors.New("stopped after 10 redirects")
-	}
-	return nil
-}
-
-// Post issues a POST to the specified URL.
-//
-// Caller should close resp.Body when done reading from it.
-//
-// If the provided body is an io.Closer, it is closed after the
-// request.
-//
-// Post is a wrapper around DefaultClient.Post.
-//
-// To set custom headers, use NewRequest and DefaultClient.Do.
-//
-// See the Client.Do method documentation for details on how redirects
-// are handled.
-//
-// To make a request with a specified context.Context, use NewRequestWithContext
-// and DefaultClient.Do.
-func Post(url, contentType string, body io.Reader) (resp *Response, err error) {
-	return DefaultClient.Post(url, contentType, body)
-}
-
-// Post issues a POST to the specified URL.
-//
-// Caller should close resp.Body when done reading from it.
-//
-// If the provided body is an io.Closer, it is closed after the
-// request.
-//
-// To set custom headers, use NewRequest and Client.Do.
-//
-// To make a request with a specified context.Context, use NewRequestWithContext
-// and Client.Do.
-//
-// See the Client.Do method documentation for details on how redirects
-// are handled.
-func (c *Client) Post(url, contentType string, body io.Reader) (resp *Response, err error) {
-	req, err := NewRequest("POST", url, body)
-	if err != nil {
-		return nil, err
-	}
-	req.Header.Set("Content-Type", contentType)
-	return c.Do(req)
-}
-
-// PostForm issues a POST to the specified URL, with data's keys and
-// values URL-encoded as the request body.
-//
-// The Content-Type header is set to application/x-www-form-urlencoded.
-// To set other headers, use NewRequest and DefaultClient.Do.
-//
-// When err is nil, resp always contains a non-nil resp.Body.
-// Caller should close resp.Body when done reading from it.
-//
-// PostForm is a wrapper around DefaultClient.PostForm.
-//
-// See the Client.Do method documentation for details on how redirects
-// are handled.
-//
-// To make a request with a specified context.Context, use NewRequestWithContext
-// and DefaultClient.Do.
-func PostForm(url string, data url.Values) (resp *Response, err error) {
-	return DefaultClient.PostForm(url, data)
-}
-
-// PostForm issues a POST to the specified URL,
-// with data's keys and values URL-encoded as the request body.
-//
-// The Content-Type header is set to application/x-www-form-urlencoded.
-// To set other headers, use NewRequest and Client.Do.
-//
-// When err is nil, resp always contains a non-nil resp.Body.
-// Caller should close resp.Body when done reading from it.
-//
-// See the Client.Do method documentation for details on how redirects
-// are handled.
-//
-// To make a request with a specified context.Context, use NewRequestWithContext
-// and Client.Do.
-func (c *Client) PostForm(url string, data url.Values) (resp *Response, err error) {
-	return c.Post(url, "application/x-www-form-urlencoded", strings.NewReader(data.Encode()))
-}
-
-// Head issues a HEAD to the specified URL. If the response is one of
-// the following redirect codes, Head follows the redirect, up to a
-// maximum of 10 redirects:
-//
-//    301 (Moved Permanently)
-//    302 (Found)
-//    303 (See Other)
-//    307 (Temporary Redirect)
-//    308 (Permanent Redirect)
-//
-// Head is a wrapper around DefaultClient.Head
-//
-// To make a request with a specified context.Context, use NewRequestWithContext
-// and DefaultClient.Do.
-func Head(url string) (resp *Response, err error) {
-	return DefaultClient.Head(url)
-}
-
-// Head issues a HEAD to the specified URL. If the response is one of the
-// following redirect codes, Head follows the redirect after calling the
-// Client's CheckRedirect function:
-//
-//    301 (Moved Permanently)
-//    302 (Found)
-//    303 (See Other)
-//    307 (Temporary Redirect)
-//    308 (Permanent Redirect)
-//
-// To make a request with a specified context.Context, use NewRequestWithContext
-// and Client.Do.
-func (c *Client) Head(url string) (resp *Response, err error) {
-	req, err := NewRequest("HEAD", url, nil)
-	if err != nil {
-		return nil, err
-	}
-	return c.Do(req)
-}
-
-// CloseIdleConnections closes any connections on its Transport which
-// were previously connected from previous requests but are now
-// sitting idle in a "keep-alive" state. It does not interrupt any
-// connections currently in use.
-//
-// If the Client's Transport does not have a CloseIdleConnections method
-// then this method does nothing.
-func (c *Client) CloseIdleConnections() {
-	type closeIdler interface {
-		CloseIdleConnections()
-	}
-	if tr, ok := c.transport().(closeIdler); ok {
-		tr.CloseIdleConnections()
-	}
-}
-
-// cancelTimerBody is an io.ReadCloser that wraps rc with two features:
-// 1) On Read error or close, the stop func is called.
-// 2) On Read failure, if reqDidTimeout is true, the error is wrapped and
-//    marked as net.Error that hit its timeout.
-type cancelTimerBody struct {
-	stop          func() // stops the time.Timer waiting to cancel the request
-	rc            io.ReadCloser
-	reqDidTimeout func() bool
-}
-
-func (b *cancelTimerBody) Read(p []byte) (n int, err error) {
-	n, err = b.rc.Read(p)
-	if err == nil {
-		return n, nil
-	}
-	if err == io.EOF {
-		return n, err
-	}
-	if b.reqDidTimeout() {
-		err = &httpError{
-			err:     err.Error() + " (Client.Timeout or context cancellation while reading body)",
-			timeout: true,
-		}
-	}
-	return n, err
-}
-
-func (b *cancelTimerBody) Close() error {
-	err := b.rc.Close()
-	b.stop()
-	return err
-}
-
-func shouldCopyHeaderOnRedirect(headerKey string, initial, dest *url.URL) bool {
-	switch CanonicalHeaderKey(headerKey) {
-	case "Authorization", "Www-Authenticate", "Cookie", "Cookie2":
-		// Permit sending auth/cookie headers from "foo.com"
-		// to "sub.foo.com".
-
-		// Note that we don't send all cookies to subdomains
-		// automatically. This function is only used for
-		// Cookies set explicitly on the initial outgoing
-		// client request. Cookies automatically added via the
-		// CookieJar mechanism continue to follow each
-		// cookie's scope as set by Set-Cookie. But for
-		// outgoing requests with the Cookie header set
-		// directly, we don't know their scope, so we assume
-		// it's for *.domain.com.
-
-		ihost := canonicalAddr(initial)
-		dhost := canonicalAddr(dest)
-		return isDomainOrSubdomain(dhost, ihost)
-	}
-	// All other headers are copied:
-	return true
-}
-
-// isDomainOrSubdomain reports whether sub is a subdomain (or exact
-// match) of the parent domain.
-//
-// Both domains must already be in canonical form.
-func isDomainOrSubdomain(sub, parent string) bool {
-	if sub == parent {
-		return true
-	}
-	// If sub is "foo.example.com" and parent is "example.com",
-	// that means sub must end in "."+parent.
-	// Do it without allocating.
-	if !strings.HasSuffix(sub, parent) {
-		return false
-	}
-	return sub[len(sub)-len(parent)-1] == '.'
-}
-
-func stripPassword(u *url.URL) string {
-	_, passSet := u.User.Password()
-	if passSet {
-		return strings.Replace(u.String(), u.User.String()+"@", u.User.Username()+":***@", 1)
-	}
-	return u.String()
-}
diff --git a/contrib/go/_std_1.18/src/net/http/cookie.go b/contrib/go/_std_1.18/src/net/http/cookie.go
deleted file mode 100644
index cb37f2351f..0000000000
--- a/contrib/go/_std_1.18/src/net/http/cookie.go
+++ /dev/null
@@ -1,464 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package http
-
-import (
-	"errors"
-	"fmt"
-	"log"
-	"net"
-	"net/http/internal/ascii"
-	"net/textproto"
-	"strconv"
-	"strings"
-	"time"
-)
-
-// A Cookie represents an HTTP cookie as sent in the Set-Cookie header of an
-// HTTP response or the Cookie header of an HTTP request.
-//
-// See https://tools.ietf.org/html/rfc6265 for details.
-type Cookie struct {
-	Name  string
-	Value string
-
-	Path       string    // optional
-	Domain     string    // optional
-	Expires    time.Time // optional
-	RawExpires string    // for reading cookies only
-
-	// MaxAge=0 means no 'Max-Age' attribute specified.
-	// MaxAge<0 means delete cookie now, equivalently 'Max-Age: 0'
-	// MaxAge>0 means Max-Age attribute present and given in seconds
-	MaxAge   int
-	Secure   bool
-	HttpOnly bool
-	SameSite SameSite
-	Raw      string
-	Unparsed []string // Raw text of unparsed attribute-value pairs
-}
-
-// SameSite allows a server to define a cookie attribute making it impossible for
-// the browser to send this cookie along with cross-site requests. The main
-// goal is to mitigate the risk of cross-origin information leakage, and provide
-// some protection against cross-site request forgery attacks.
-//
-// See https://tools.ietf.org/html/draft-ietf-httpbis-cookie-same-site-00 for details.
-type SameSite int
-
-const (
-	SameSiteDefaultMode SameSite = iota + 1
-	SameSiteLaxMode
-	SameSiteStrictMode
-	SameSiteNoneMode
-)
-
-// readSetCookies parses all "Set-Cookie" values from
-// the header h and returns the successfully parsed Cookies.
-func readSetCookies(h Header) []*Cookie {
-	cookieCount := len(h["Set-Cookie"])
-	if cookieCount == 0 {
-		return []*Cookie{}
-	}
-	cookies := make([]*Cookie, 0, cookieCount)
-	for _, line := range h["Set-Cookie"] {
-		parts := strings.Split(textproto.TrimString(line), ";")
-		if len(parts) == 1 && parts[0] == "" {
-			continue
-		}
-		parts[0] = textproto.TrimString(parts[0])
-		name, value, ok := strings.Cut(parts[0], "=")
-		if !ok {
-			continue
-		}
-		if !isCookieNameValid(name) {
-			continue
-		}
-		value, ok = parseCookieValue(value, true)
-		if !ok {
-			continue
-		}
-		c := &Cookie{
-			Name:  name,
-			Value: value,
-			Raw:   line,
-		}
-		for i := 1; i < len(parts); i++ {
-			parts[i] = textproto.TrimString(parts[i])
-			if len(parts[i]) == 0 {
-				continue
-			}
-
-			attr, val, _ := strings.Cut(parts[i], "=")
-			lowerAttr, isASCII := ascii.ToLower(attr)
-			if !isASCII {
-				continue
-			}
-			val, ok = parseCookieValue(val, false)
-			if !ok {
-				c.Unparsed = append(c.Unparsed, parts[i])
-				continue
-			}
-
-			switch lowerAttr {
-			case "samesite":
-				lowerVal, ascii := ascii.ToLower(val)
-				if !ascii {
-					c.SameSite = SameSiteDefaultMode
-					continue
-				}
-				switch lowerVal {
-				case "lax":
-					c.SameSite = SameSiteLaxMode
-				case "strict":
-					c.SameSite = SameSiteStrictMode
-				case "none":
-					c.SameSite = SameSiteNoneMode
-				default:
-					c.SameSite = SameSiteDefaultMode
-				}
-				continue
-			case "secure":
-				c.Secure = true
-				continue
-			case "httponly":
-				c.HttpOnly = true
-				continue
-			case "domain":
-				c.Domain = val
-				continue
-			case "max-age":
-				secs, err := strconv.Atoi(val)
-				if err != nil || secs != 0 && val[0] == '0' {
-					break
-				}
-				if secs <= 0 {
-					secs = -1
-				}
-				c.MaxAge = secs
-				continue
-			case "expires":
-				c.RawExpires = val
-				exptime, err := time.Parse(time.RFC1123, val)
-				if err != nil {
-					exptime, err = time.Parse("Mon, 02-Jan-2006 15:04:05 MST", val)
-					if err != nil {
-						c.Expires = time.Time{}
-						break
-					}
-				}
-				c.Expires = exptime.UTC()
-				continue
-			case "path":
-				c.Path = val
-				continue
-			}
-			c.Unparsed = append(c.Unparsed, parts[i])
-		}
-		cookies = append(cookies, c)
-	}
-	return cookies
-}
-
-// SetCookie adds a Set-Cookie header to the provided ResponseWriter's headers.
-// The provided cookie must have a valid Name. Invalid cookies may be
-// silently dropped.
-func SetCookie(w ResponseWriter, cookie *Cookie) {
-	if v := cookie.String(); v != "" {
-		w.Header().Add("Set-Cookie", v)
-	}
-}
-
-// String returns the serialization of the cookie for use in a Cookie
-// header (if only Name and Value are set) or a Set-Cookie response
-// header (if other fields are set).
-// If c is nil or c.Name is invalid, the empty string is returned.
-func (c *Cookie) String() string {
-	if c == nil || !isCookieNameValid(c.Name) {
-		return ""
-	}
-	// extraCookieLength derived from typical length of cookie attributes
-	// see RFC 6265 Sec 4.1.
-	const extraCookieLength = 110
-	var b strings.Builder
-	b.Grow(len(c.Name) + len(c.Value) + len(c.Domain) + len(c.Path) + extraCookieLength)
-	b.WriteString(c.Name)
-	b.WriteRune('=')
-	b.WriteString(sanitizeCookieValue(c.Value))
-
-	if len(c.Path) > 0 {
-		b.WriteString("; Path=")
-		b.WriteString(sanitizeCookiePath(c.Path))
-	}
-	if len(c.Domain) > 0 {
-		if validCookieDomain(c.Domain) {
-			// A c.Domain containing illegal characters is not
-			// sanitized but simply dropped which turns the cookie
-			// into a host-only cookie. A leading dot is okay
-			// but won't be sent.
-			d := c.Domain
-			if d[0] == '.' {
-				d = d[1:]
-			}
-			b.WriteString("; Domain=")
-			b.WriteString(d)
-		} else {
-			log.Printf("net/http: invalid Cookie.Domain %q; dropping domain attribute", c.Domain)
-		}
-	}
-	var buf [len(TimeFormat)]byte
-	if validCookieExpires(c.Expires) {
-		b.WriteString("; Expires=")
-		b.Write(c.Expires.UTC().AppendFormat(buf[:0], TimeFormat))
-	}
-	if c.MaxAge > 0 {
-		b.WriteString("; Max-Age=")
-		b.Write(strconv.AppendInt(buf[:0], int64(c.MaxAge), 10))
-	} else if c.MaxAge < 0 {
-		b.WriteString("; Max-Age=0")
-	}
-	if c.HttpOnly {
-		b.WriteString("; HttpOnly")
-	}
-	if c.Secure {
-		b.WriteString("; Secure")
-	}
-	switch c.SameSite {
-	case SameSiteDefaultMode:
-		// Skip, default mode is obtained by not emitting the attribute.
-	case SameSiteNoneMode:
-		b.WriteString("; SameSite=None")
-	case SameSiteLaxMode:
-		b.WriteString("; SameSite=Lax")
-	case SameSiteStrictMode:
-		b.WriteString("; SameSite=Strict")
-	}
-	return b.String()
-}
-
-// Valid reports whether the cookie is valid.
-func (c *Cookie) Valid() error {
-	if c == nil {
-		return errors.New("http: nil Cookie")
-	}
-	if !isCookieNameValid(c.Name) {
-		return errors.New("http: invalid Cookie.Name")
-	}
-	if !validCookieExpires(c.Expires) {
-		return errors.New("http: invalid Cookie.Expires")
-	}
-	for i := 0; i < len(c.Value); i++ {
-		if !validCookieValueByte(c.Value[i]) {
-			return fmt.Errorf("http: invalid byte %q in Cookie.Value", c.Value[i])
-		}
-	}
-	if len(c.Path) > 0 {
-		for i := 0; i < len(c.Path); i++ {
-			if !validCookiePathByte(c.Path[i]) {
-				return fmt.Errorf("http: invalid byte %q in Cookie.Path", c.Path[i])
-			}
-		}
-	}
-	if len(c.Domain) > 0 {
-		if !validCookieDomain(c.Domain) {
-			return errors.New("http: invalid Cookie.Domain")
-		}
-	}
-	return nil
-}
-
-// readCookies parses all "Cookie" values from the header h and
-// returns the successfully parsed Cookies.
-//
-// if filter isn't empty, only cookies of that name are returned
-func readCookies(h Header, filter string) []*Cookie {
-	lines := h["Cookie"]
-	if len(lines) == 0 {
-		return []*Cookie{}
-	}
-
-	cookies := make([]*Cookie, 0, len(lines)+strings.Count(lines[0], ";"))
-	for _, line := range lines {
-		line = textproto.TrimString(line)
-
-		var part string
-		for len(line) > 0 { // continue since we have rest
-			part, line, _ = strings.Cut(line, ";")
-			part = textproto.TrimString(part)
-			if part == "" {
-				continue
-			}
-			name, val, _ := strings.Cut(part, "=")
-			if !isCookieNameValid(name) {
-				continue
-			}
-			if filter != "" && filter != name {
-				continue
-			}
-			val, ok := parseCookieValue(val, true)
-			if !ok {
-				continue
-			}
-			cookies = append(cookies, &Cookie{Name: name, Value: val})
-		}
-	}
-	return cookies
-}
-
-// validCookieDomain reports whether v is a valid cookie domain-value.
-func validCookieDomain(v string) bool {
-	if isCookieDomainName(v) {
-		return true
-	}
-	if net.ParseIP(v) != nil && !strings.Contains(v, ":") {
-		return true
-	}
-	return false
-}
-
-// validCookieExpires reports whether v is a valid cookie expires-value.
-func validCookieExpires(t time.Time) bool {
-	// IETF RFC 6265 Section 5.1.1.5, the year must not be less than 1601
-	return t.Year() >= 1601
-}
-
-// isCookieDomainName reports whether s is a valid domain name or a valid
-// domain name with a leading dot '.'.  It is almost a direct copy of
-// package net's isDomainName.
-func isCookieDomainName(s string) bool {
-	if len(s) == 0 {
-		return false
-	}
-	if len(s) > 255 {
-		return false
-	}
-
-	if s[0] == '.' {
-		// A cookie a domain attribute may start with a leading dot.
-		s = s[1:]
-	}
-	last := byte('.')
-	ok := false // Ok once we've seen a letter.
-	partlen := 0
-	for i := 0; i < len(s); i++ {
-		c := s[i]
-		switch {
-		default:
-			return false
-		case 'a' <= c && c <= 'z' || 'A' <= c && c <= 'Z':
-			// No '_' allowed here (in contrast to package net).
-			ok = true
-			partlen++
-		case '0' <= c && c <= '9':
-			// fine
-			partlen++
-		case c == '-':
-			// Byte before dash cannot be dot.
-			if last == '.' {
-				return false
-			}
-			partlen++
-		case c == '.':
-			// Byte before dot cannot be dot, dash.
-			if last == '.' || last == '-' {
-				return false
-			}
-			if partlen > 63 || partlen == 0 {
-				return false
-			}
-			partlen = 0
-		}
-		last = c
-	}
-	if last == '-' || partlen > 63 {
-		return false
-	}
-
-	return ok
-}
-
-var cookieNameSanitizer = strings.NewReplacer("\n", "-", "\r", "-")
-
-func sanitizeCookieName(n string) string {
-	return cookieNameSanitizer.Replace(n)
-}
-
-// sanitizeCookieValue produces a suitable cookie-value from v.
-// https://tools.ietf.org/html/rfc6265#section-4.1.1
-// cookie-value      = *cookie-octet / ( DQUOTE *cookie-octet DQUOTE )
-// cookie-octet      = %x21 / %x23-2B / %x2D-3A / %x3C-5B / %x5D-7E
-//           ; US-ASCII characters excluding CTLs,
-//           ; whitespace DQUOTE, comma, semicolon,
-//           ; and backslash
-// We loosen this as spaces and commas are common in cookie values
-// but we produce a quoted cookie-value if and only if v contains
-// commas or spaces.
-// See https://golang.org/issue/7243 for the discussion.
-func sanitizeCookieValue(v string) string {
-	v = sanitizeOrWarn("Cookie.Value", validCookieValueByte, v)
-	if len(v) == 0 {
-		return v
-	}
-	if strings.ContainsAny(v, " ,") {
-		return `"` + v + `"`
-	}
-	return v
-}
-
-func validCookieValueByte(b byte) bool {
-	return 0x20 <= b && b < 0x7f && b != '"' && b != ';' && b != '\\'
-}
-
-// path-av           = "Path=" path-value
-// path-value        = <any CHAR except CTLs or ";">
-func sanitizeCookiePath(v string) string {
-	return sanitizeOrWarn("Cookie.Path", validCookiePathByte, v)
-}
-
-func validCookiePathByte(b byte) bool {
-	return 0x20 <= b && b < 0x7f && b != ';'
-}
-
-func sanitizeOrWarn(fieldName string, valid func(byte) bool, v string) string {
-	ok := true
-	for i := 0; i < len(v); i++ {
-		if valid(v[i]) {
-			continue
-		}
-		log.Printf("net/http: invalid byte %q in %s; dropping invalid bytes", v[i], fieldName)
-		ok = false
-		break
-	}
-	if ok {
-		return v
-	}
-	buf := make([]byte, 0, len(v))
-	for i := 0; i < len(v); i++ {
-		if b := v[i]; valid(b) {
-			buf = append(buf, b)
-		}
-	}
-	return string(buf)
-}
-
-func parseCookieValue(raw string, allowDoubleQuote bool) (string, bool) {
-	// Strip the quotes, if present.
-	if allowDoubleQuote && len(raw) > 1 && raw[0] == '"' && raw[len(raw)-1] == '"' {
-		raw = raw[1 : len(raw)-1]
-	}
-	for i := 0; i < len(raw); i++ {
-		if !validCookieValueByte(raw[i]) {
-			return "", false
-		}
-	}
-	return raw, true
-}
-
-func isCookieNameValid(raw string) bool {
-	if raw == "" {
-		return false
-	}
-	return strings.IndexFunc(raw, isNotToken) < 0
-}
diff --git a/contrib/go/_std_1.18/src/net/http/doc.go b/contrib/go/_std_1.18/src/net/http/doc.go
deleted file mode 100644
index ae9b708c69..0000000000
--- a/contrib/go/_std_1.18/src/net/http/doc.go
+++ /dev/null
@@ -1,107 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-/*
-Package http provides HTTP client and server implementations.
-
-Get, Head, Post, and PostForm make HTTP (or HTTPS) requests:
-
-	resp, err := http.Get("http://example.com/")
-	...
-	resp, err := http.Post("http://example.com/upload", "image/jpeg", &buf)
-	...
-	resp, err := http.PostForm("http://example.com/form",
-		url.Values{"key": {"Value"}, "id": {"123"}})
-
-The client must close the response body when finished with it:
-
-	resp, err := http.Get("http://example.com/")
-	if err != nil {
-		// handle error
-	}
-	defer resp.Body.Close()
-	body, err := io.ReadAll(resp.Body)
-	// ...
-
-For control over HTTP client headers, redirect policy, and other
-settings, create a Client:
-
-	client := &http.Client{
-		CheckRedirect: redirectPolicyFunc,
-	}
-
-	resp, err := client.Get("http://example.com")
-	// ...
-
-	req, err := http.NewRequest("GET", "http://example.com", nil)
-	// ...
-	req.Header.Add("If-None-Match", `W/"wyzzy"`)
-	resp, err := client.Do(req)
-	// ...
-
-For control over proxies, TLS configuration, keep-alives,
-compression, and other settings, create a Transport:
-
-	tr := &http.Transport{
-		MaxIdleConns:       10,
-		IdleConnTimeout:    30 * time.Second,
-		DisableCompression: true,
-	}
-	client := &http.Client{Transport: tr}
-	resp, err := client.Get("https://example.com")
-
-Clients and Transports are safe for concurrent use by multiple
-goroutines and for efficiency should only be created once and re-used.
-
-ListenAndServe starts an HTTP server with a given address and handler.
-The handler is usually nil, which means to use DefaultServeMux.
-Handle and HandleFunc add handlers to DefaultServeMux:
-
-	http.Handle("/foo", fooHandler)
-
-	http.HandleFunc("/bar", func(w http.ResponseWriter, r *http.Request) {
-		fmt.Fprintf(w, "Hello, %q", html.EscapeString(r.URL.Path))
-	})
-
-	log.Fatal(http.ListenAndServe(":8080", nil))
-
-More control over the server's behavior is available by creating a
-custom Server:
-
-	s := &http.Server{
-		Addr:           ":8080",
-		Handler:        myHandler,
-		ReadTimeout:    10 * time.Second,
-		WriteTimeout:   10 * time.Second,
-		MaxHeaderBytes: 1 << 20,
-	}
-	log.Fatal(s.ListenAndServe())
-
-Starting with Go 1.6, the http package has transparent support for the
-HTTP/2 protocol when using HTTPS. Programs that must disable HTTP/2
-can do so by setting Transport.TLSNextProto (for clients) or
-Server.TLSNextProto (for servers) to a non-nil, empty
-map. Alternatively, the following GODEBUG environment variables are
-currently supported:
-
-	GODEBUG=http2client=0  # disable HTTP/2 client support
-	GODEBUG=http2server=0  # disable HTTP/2 server support
-	GODEBUG=http2debug=1   # enable verbose HTTP/2 debug logs
-	GODEBUG=http2debug=2   # ... even more verbose, with frame dumps
-
-The GODEBUG variables are not covered by Go's API compatibility
-promise. Please report any issues before disabling HTTP/2
-support: https://golang.org/s/http2bug
-
-The http package's Transport and Server both automatically enable
-HTTP/2 support for simple configurations. To enable HTTP/2 for more
-complex configurations, to use lower-level HTTP/2 features, or to use
-a newer version of Go's http2 package, import "golang.org/x/net/http2"
-directly and use its ConfigureTransport and/or ConfigureServer
-functions. Manually configuring HTTP/2 via the golang.org/x/net/http2
-package takes precedence over the net/http package's built-in HTTP/2
-support.
-
-*/
-package http
diff --git a/contrib/go/_std_1.18/src/net/http/filetransport.go b/contrib/go/_std_1.18/src/net/http/filetransport.go
deleted file mode 100644
index 32126d7ec0..0000000000
--- a/contrib/go/_std_1.18/src/net/http/filetransport.go
+++ /dev/null
@@ -1,123 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package http
-
-import (
-	"fmt"
-	"io"
-)
-
-// fileTransport implements RoundTripper for the 'file' protocol.
-type fileTransport struct {
-	fh fileHandler
-}
-
-// NewFileTransport returns a new RoundTripper, serving the provided
-// FileSystem. The returned RoundTripper ignores the URL host in its
-// incoming requests, as well as most other properties of the
-// request.
-//
-// The typical use case for NewFileTransport is to register the "file"
-// protocol with a Transport, as in:
-//
-//   t := &http.Transport{}
-//   t.RegisterProtocol("file", http.NewFileTransport(http.Dir("/")))
-//   c := &http.Client{Transport: t}
-//   res, err := c.Get("file:///etc/passwd")
-//   ...
-func NewFileTransport(fs FileSystem) RoundTripper {
-	return fileTransport{fileHandler{fs}}
-}
-
-func (t fileTransport) RoundTrip(req *Request) (resp *Response, err error) {
-	// We start ServeHTTP in a goroutine, which may take a long
-	// time if the file is large. The newPopulateResponseWriter
-	// call returns a channel which either ServeHTTP or finish()
-	// sends our *Response on, once the *Response itself has been
-	// populated (even if the body itself is still being
-	// written to the res.Body, a pipe)
-	rw, resc := newPopulateResponseWriter()
-	go func() {
-		t.fh.ServeHTTP(rw, req)
-		rw.finish()
-	}()
-	return <-resc, nil
-}
-
-func newPopulateResponseWriter() (*populateResponse, <-chan *Response) {
-	pr, pw := io.Pipe()
-	rw := &populateResponse{
-		ch: make(chan *Response),
-		pw: pw,
-		res: &Response{
-			Proto:      "HTTP/1.0",
-			ProtoMajor: 1,
-			Header:     make(Header),
-			Close:      true,
-			Body:       pr,
-		},
-	}
-	return rw, rw.ch
-}
-
-// populateResponse is a ResponseWriter that populates the *Response
-// in res, and writes its body to a pipe connected to the response
-// body. Once writes begin or finish() is called, the response is sent
-// on ch.
-type populateResponse struct {
-	res          *Response
-	ch           chan *Response
-	wroteHeader  bool
-	hasContent   bool
-	sentResponse bool
-	pw           *io.PipeWriter
-}
-
-func (pr *populateResponse) finish() {
-	if !pr.wroteHeader {
-		pr.WriteHeader(500)
-	}
-	if !pr.sentResponse {
-		pr.sendResponse()
-	}
-	pr.pw.Close()
-}
-
-func (pr *populateResponse) sendResponse() {
-	if pr.sentResponse {
-		return
-	}
-	pr.sentResponse = true
-
-	if pr.hasContent {
-		pr.res.ContentLength = -1
-	}
-	pr.ch <- pr.res
-}
-
-func (pr *populateResponse) Header() Header {
-	return pr.res.Header
-}
-
-func (pr *populateResponse) WriteHeader(code int) {
-	if pr.wroteHeader {
-		return
-	}
-	pr.wroteHeader = true
-
-	pr.res.StatusCode = code
-	pr.res.Status = fmt.Sprintf("%d %s", code, StatusText(code))
-}
-
-func (pr *populateResponse) Write(p []byte) (n int, err error) {
-	if !pr.wroteHeader {
-		pr.WriteHeader(StatusOK)
-	}
-	pr.hasContent = true
-	if !pr.sentResponse {
-		pr.sendResponse()
-	}
-	return pr.pw.Write(p)
-}
diff --git a/contrib/go/_std_1.18/src/net/http/fs.go b/contrib/go/_std_1.18/src/net/http/fs.go
deleted file mode 100644
index 6caee9ed93..0000000000
--- a/contrib/go/_std_1.18/src/net/http/fs.go
+++ /dev/null
@@ -1,972 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// HTTP file system request handler
-
-package http
-
-import (
-	"errors"
-	"fmt"
-	"io"
-	"io/fs"
-	"mime"
-	"mime/multipart"
-	"net/textproto"
-	"net/url"
-	"os"
-	"path"
-	"path/filepath"
-	"sort"
-	"strconv"
-	"strings"
-	"time"
-)
-
-// A Dir implements FileSystem using the native file system restricted to a
-// specific directory tree.
-//
-// While the FileSystem.Open method takes '/'-separated paths, a Dir's string
-// value is a filename on the native file system, not a URL, so it is separated
-// by filepath.Separator, which isn't necessarily '/'.
-//
-// Note that Dir could expose sensitive files and directories. Dir will follow
-// symlinks pointing out of the directory tree, which can be especially dangerous
-// if serving from a directory in which users are able to create arbitrary symlinks.
-// Dir will also allow access to files and directories starting with a period,
-// which could expose sensitive directories like .git or sensitive files like
-// .htpasswd. To exclude files with a leading period, remove the files/directories
-// from the server or create a custom FileSystem implementation.
-//
-// An empty Dir is treated as ".".
-type Dir string
-
-// mapOpenError maps the provided non-nil error from opening name
-// to a possibly better non-nil error. In particular, it turns OS-specific errors
-// about opening files in non-directories into fs.ErrNotExist. See Issues 18984 and 49552.
-func mapOpenError(originalErr error, name string, sep rune, stat func(string) (fs.FileInfo, error)) error {
-	if errors.Is(originalErr, fs.ErrNotExist) || errors.Is(originalErr, fs.ErrPermission) {
-		return originalErr
-	}
-
-	parts := strings.Split(name, string(sep))
-	for i := range parts {
-		if parts[i] == "" {
-			continue
-		}
-		fi, err := stat(strings.Join(parts[:i+1], string(sep)))
-		if err != nil {
-			return originalErr
-		}
-		if !fi.IsDir() {
-			return fs.ErrNotExist
-		}
-	}
-	return originalErr
-}
-
-// Open implements FileSystem using os.Open, opening files for reading rooted
-// and relative to the directory d.
-func (d Dir) Open(name string) (File, error) {
-	if filepath.Separator != '/' && strings.ContainsRune(name, filepath.Separator) {
-		return nil, errors.New("http: invalid character in file path")
-	}
-	dir := string(d)
-	if dir == "" {
-		dir = "."
-	}
-	fullName := filepath.Join(dir, filepath.FromSlash(path.Clean("/"+name)))
-	f, err := os.Open(fullName)
-	if err != nil {
-		return nil, mapOpenError(err, fullName, filepath.Separator, os.Stat)
-	}
-	return f, nil
-}
-
-// A FileSystem implements access to a collection of named files.
-// The elements in a file path are separated by slash ('/', U+002F)
-// characters, regardless of host operating system convention.
-// See the FileServer function to convert a FileSystem to a Handler.
-//
-// This interface predates the fs.FS interface, which can be used instead:
-// the FS adapter function converts an fs.FS to a FileSystem.
-type FileSystem interface {
-	Open(name string) (File, error)
-}
-
-// A File is returned by a FileSystem's Open method and can be
-// served by the FileServer implementation.
-//
-// The methods should behave the same as those on an *os.File.
-type File interface {
-	io.Closer
-	io.Reader
-	io.Seeker
-	Readdir(count int) ([]fs.FileInfo, error)
-	Stat() (fs.FileInfo, error)
-}
-
-type anyDirs interface {
-	len() int
-	name(i int) string
-	isDir(i int) bool
-}
-
-type fileInfoDirs []fs.FileInfo
-
-func (d fileInfoDirs) len() int          { return len(d) }
-func (d fileInfoDirs) isDir(i int) bool  { return d[i].IsDir() }
-func (d fileInfoDirs) name(i int) string { return d[i].Name() }
-
-type dirEntryDirs []fs.DirEntry
-
-func (d dirEntryDirs) len() int          { return len(d) }
-func (d dirEntryDirs) isDir(i int) bool  { return d[i].IsDir() }
-func (d dirEntryDirs) name(i int) string { return d[i].Name() }
-
-func dirList(w ResponseWriter, r *Request, f File) {
-	// Prefer to use ReadDir instead of Readdir,
-	// because the former doesn't require calling
-	// Stat on every entry of a directory on Unix.
-	var dirs anyDirs
-	var err error
-	if d, ok := f.(fs.ReadDirFile); ok {
-		var list dirEntryDirs
-		list, err = d.ReadDir(-1)
-		dirs = list
-	} else {
-		var list fileInfoDirs
-		list, err = f.Readdir(-1)
-		dirs = list
-	}
-
-	if err != nil {
-		logf(r, "http: error reading directory: %v", err)
-		Error(w, "Error reading directory", StatusInternalServerError)
-		return
-	}
-	sort.Slice(dirs, func(i, j int) bool { return dirs.name(i) < dirs.name(j) })
-
-	w.Header().Set("Content-Type", "text/html; charset=utf-8")
-	fmt.Fprintf(w, "<pre>\n")
-	for i, n := 0, dirs.len(); i < n; i++ {
-		name := dirs.name(i)
-		if dirs.isDir(i) {
-			name += "/"
-		}
-		// name may contain '?' or '#', which must be escaped to remain
-		// part of the URL path, and not indicate the start of a query
-		// string or fragment.
-		url := url.URL{Path: name}
-		fmt.Fprintf(w, "<a href=\"%s\">%s</a>\n", url.String(), htmlReplacer.Replace(name))
-	}
-	fmt.Fprintf(w, "</pre>\n")
-}
-
-// ServeContent replies to the request using the content in the
-// provided ReadSeeker. The main benefit of ServeContent over io.Copy
-// is that it handles Range requests properly, sets the MIME type, and
-// handles If-Match, If-Unmodified-Since, If-None-Match, If-Modified-Since,
-// and If-Range requests.
-//
-// If the response's Content-Type header is not set, ServeContent
-// first tries to deduce the type from name's file extension and,
-// if that fails, falls back to reading the first block of the content
-// and passing it to DetectContentType.
-// The name is otherwise unused; in particular it can be empty and is
-// never sent in the response.
-//
-// If modtime is not the zero time or Unix epoch, ServeContent
-// includes it in a Last-Modified header in the response. If the
-// request includes an If-Modified-Since header, ServeContent uses
-// modtime to decide whether the content needs to be sent at all.
-//
-// The content's Seek method must work: ServeContent uses
-// a seek to the end of the content to determine its size.
-//
-// If the caller has set w's ETag header formatted per RFC 7232, section 2.3,
-// ServeContent uses it to handle requests using If-Match, If-None-Match, or If-Range.
-//
-// Note that *os.File implements the io.ReadSeeker interface.
-func ServeContent(w ResponseWriter, req *Request, name string, modtime time.Time, content io.ReadSeeker) {
-	sizeFunc := func() (int64, error) {
-		size, err := content.Seek(0, io.SeekEnd)
-		if err != nil {
-			return 0, errSeeker
-		}
-		_, err = content.Seek(0, io.SeekStart)
-		if err != nil {
-			return 0, errSeeker
-		}
-		return size, nil
-	}
-	serveContent(w, req, name, modtime, sizeFunc, content)
-}
-
-// errSeeker is returned by ServeContent's sizeFunc when the content
-// doesn't seek properly. The underlying Seeker's error text isn't
-// included in the sizeFunc reply so it's not sent over HTTP to end
-// users.
-var errSeeker = errors.New("seeker can't seek")
-
-// errNoOverlap is returned by serveContent's parseRange if first-byte-pos of
-// all of the byte-range-spec values is greater than the content size.
-var errNoOverlap = errors.New("invalid range: failed to overlap")
-
-// if name is empty, filename is unknown. (used for mime type, before sniffing)
-// if modtime.IsZero(), modtime is unknown.
-// content must be seeked to the beginning of the file.
-// The sizeFunc is called at most once. Its error, if any, is sent in the HTTP response.
-func serveContent(w ResponseWriter, r *Request, name string, modtime time.Time, sizeFunc func() (int64, error), content io.ReadSeeker) {
-	setLastModified(w, modtime)
-	done, rangeReq := checkPreconditions(w, r, modtime)
-	if done {
-		return
-	}
-
-	code := StatusOK
-
-	// If Content-Type isn't set, use the file's extension to find it, but
-	// if the Content-Type is unset explicitly, do not sniff the type.
-	ctypes, haveType := w.Header()["Content-Type"]
-	var ctype string
-	if !haveType {
-		ctype = mime.TypeByExtension(filepath.Ext(name))
-		if ctype == "" {
-			// read a chunk to decide between utf-8 text and binary
-			var buf [sniffLen]byte
-			n, _ := io.ReadFull(content, buf[:])
-			ctype = DetectContentType(buf[:n])
-			_, err := content.Seek(0, io.SeekStart) // rewind to output whole file
-			if err != nil {
-				Error(w, "seeker can't seek", StatusInternalServerError)
-				return
-			}
-		}
-		w.Header().Set("Content-Type", ctype)
-	} else if len(ctypes) > 0 {
-		ctype = ctypes[0]
-	}
-
-	size, err := sizeFunc()
-	if err != nil {
-		Error(w, err.Error(), StatusInternalServerError)
-		return
-	}
-
-	// handle Content-Range header.
-	sendSize := size
-	var sendContent io.Reader = content
-	if size >= 0 {
-		ranges, err := parseRange(rangeReq, size)
-		if err != nil {
-			if err == errNoOverlap {
-				w.Header().Set("Content-Range", fmt.Sprintf("bytes */%d", size))
-			}
-			Error(w, err.Error(), StatusRequestedRangeNotSatisfiable)
-			return
-		}
-		if sumRangesSize(ranges) > size {
-			// The total number of bytes in all the ranges
-			// is larger than the size of the file by
-			// itself, so this is probably an attack, or a
-			// dumb client. Ignore the range request.
-			ranges = nil
-		}
-		switch {
-		case len(ranges) == 1:
-			// RFC 7233, Section 4.1:
-			// "If a single part is being transferred, the server
-			// generating the 206 response MUST generate a
-			// Content-Range header field, describing what range
-			// of the selected representation is enclosed, and a
-			// payload consisting of the range.
-			// ...
-			// A server MUST NOT generate a multipart response to
-			// a request for a single range, since a client that
-			// does not request multiple parts might not support
-			// multipart responses."
-			ra := ranges[0]
-			if _, err := content.Seek(ra.start, io.SeekStart); err != nil {
-				Error(w, err.Error(), StatusRequestedRangeNotSatisfiable)
-				return
-			}
-			sendSize = ra.length
-			code = StatusPartialContent
-			w.Header().Set("Content-Range", ra.contentRange(size))
-		case len(ranges) > 1:
-			sendSize = rangesMIMESize(ranges, ctype, size)
-			code = StatusPartialContent
-
-			pr, pw := io.Pipe()
-			mw := multipart.NewWriter(pw)
-			w.Header().Set("Content-Type", "multipart/byteranges; boundary="+mw.Boundary())
-			sendContent = pr
-			defer pr.Close() // cause writing goroutine to fail and exit if CopyN doesn't finish.
-			go func() {
-				for _, ra := range ranges {
-					part, err := mw.CreatePart(ra.mimeHeader(ctype, size))
-					if err != nil {
-						pw.CloseWithError(err)
-						return
-					}
-					if _, err := content.Seek(ra.start, io.SeekStart); err != nil {
-						pw.CloseWithError(err)
-						return
-					}
-					if _, err := io.CopyN(part, content, ra.length); err != nil {
-						pw.CloseWithError(err)
-						return
-					}
-				}
-				mw.Close()
-				pw.Close()
-			}()
-		}
-
-		w.Header().Set("Accept-Ranges", "bytes")
-		if w.Header().Get("Content-Encoding") == "" {
-			w.Header().Set("Content-Length", strconv.FormatInt(sendSize, 10))
-		}
-	}
-
-	w.WriteHeader(code)
-
-	if r.Method != "HEAD" {
-		io.CopyN(w, sendContent, sendSize)
-	}
-}
-
-// scanETag determines if a syntactically valid ETag is present at s. If so,
-// the ETag and remaining text after consuming ETag is returned. Otherwise,
-// it returns "", "".
-func scanETag(s string) (etag string, remain string) {
-	s = textproto.TrimString(s)
-	start := 0
-	if strings.HasPrefix(s, "W/") {
-		start = 2
-	}
-	if len(s[start:]) < 2 || s[start] != '"' {
-		return "", ""
-	}
-	// ETag is either W/"text" or "text".
-	// See RFC 7232 2.3.
-	for i := start + 1; i < len(s); i++ {
-		c := s[i]
-		switch {
-		// Character values allowed in ETags.
-		case c == 0x21 || c >= 0x23 && c <= 0x7E || c >= 0x80:
-		case c == '"':
-			return s[:i+1], s[i+1:]
-		default:
-			return "", ""
-		}
-	}
-	return "", ""
-}
-
-// etagStrongMatch reports whether a and b match using strong ETag comparison.
-// Assumes a and b are valid ETags.
-func etagStrongMatch(a, b string) bool {
-	return a == b && a != "" && a[0] == '"'
-}
-
-// etagWeakMatch reports whether a and b match using weak ETag comparison.
-// Assumes a and b are valid ETags.
-func etagWeakMatch(a, b string) bool {
-	return strings.TrimPrefix(a, "W/") == strings.TrimPrefix(b, "W/")
-}
-
-// condResult is the result of an HTTP request precondition check.
-// See https://tools.ietf.org/html/rfc7232 section 3.
-type condResult int
-
-const (
-	condNone condResult = iota
-	condTrue
-	condFalse
-)
-
-func checkIfMatch(w ResponseWriter, r *Request) condResult {
-	im := r.Header.Get("If-Match")
-	if im == "" {
-		return condNone
-	}
-	for {
-		im = textproto.TrimString(im)
-		if len(im) == 0 {
-			break
-		}
-		if im[0] == ',' {
-			im = im[1:]
-			continue
-		}
-		if im[0] == '*' {
-			return condTrue
-		}
-		etag, remain := scanETag(im)
-		if etag == "" {
-			break
-		}
-		if etagStrongMatch(etag, w.Header().get("Etag")) {
-			return condTrue
-		}
-		im = remain
-	}
-
-	return condFalse
-}
-
-func checkIfUnmodifiedSince(r *Request, modtime time.Time) condResult {
-	ius := r.Header.Get("If-Unmodified-Since")
-	if ius == "" || isZeroTime(modtime) {
-		return condNone
-	}
-	t, err := ParseTime(ius)
-	if err != nil {
-		return condNone
-	}
-
-	// The Last-Modified header truncates sub-second precision so
-	// the modtime needs to be truncated too.
-	modtime = modtime.Truncate(time.Second)
-	if modtime.Before(t) || modtime.Equal(t) {
-		return condTrue
-	}
-	return condFalse
-}
-
-func checkIfNoneMatch(w ResponseWriter, r *Request) condResult {
-	inm := r.Header.get("If-None-Match")
-	if inm == "" {
-		return condNone
-	}
-	buf := inm
-	for {
-		buf = textproto.TrimString(buf)
-		if len(buf) == 0 {
-			break
-		}
-		if buf[0] == ',' {
-			buf = buf[1:]
-			continue
-		}
-		if buf[0] == '*' {
-			return condFalse
-		}
-		etag, remain := scanETag(buf)
-		if etag == "" {
-			break
-		}
-		if etagWeakMatch(etag, w.Header().get("Etag")) {
-			return condFalse
-		}
-		buf = remain
-	}
-	return condTrue
-}
-
-func checkIfModifiedSince(r *Request, modtime time.Time) condResult {
-	if r.Method != "GET" && r.Method != "HEAD" {
-		return condNone
-	}
-	ims := r.Header.Get("If-Modified-Since")
-	if ims == "" || isZeroTime(modtime) {
-		return condNone
-	}
-	t, err := ParseTime(ims)
-	if err != nil {
-		return condNone
-	}
-	// The Last-Modified header truncates sub-second precision so
-	// the modtime needs to be truncated too.
-	modtime = modtime.Truncate(time.Second)
-	if modtime.Before(t) || modtime.Equal(t) {
-		return condFalse
-	}
-	return condTrue
-}
-
-func checkIfRange(w ResponseWriter, r *Request, modtime time.Time) condResult {
-	if r.Method != "GET" && r.Method != "HEAD" {
-		return condNone
-	}
-	ir := r.Header.get("If-Range")
-	if ir == "" {
-		return condNone
-	}
-	etag, _ := scanETag(ir)
-	if etag != "" {
-		if etagStrongMatch(etag, w.Header().Get("Etag")) {
-			return condTrue
-		} else {
-			return condFalse
-		}
-	}
-	// The If-Range value is typically the ETag value, but it may also be
-	// the modtime date. See golang.org/issue/8367.
-	if modtime.IsZero() {
-		return condFalse
-	}
-	t, err := ParseTime(ir)
-	if err != nil {
-		return condFalse
-	}
-	if t.Unix() == modtime.Unix() {
-		return condTrue
-	}
-	return condFalse
-}
-
-var unixEpochTime = time.Unix(0, 0)
-
-// isZeroTime reports whether t is obviously unspecified (either zero or Unix()=0).
-func isZeroTime(t time.Time) bool {
-	return t.IsZero() || t.Equal(unixEpochTime)
-}
-
-func setLastModified(w ResponseWriter, modtime time.Time) {
-	if !isZeroTime(modtime) {
-		w.Header().Set("Last-Modified", modtime.UTC().Format(TimeFormat))
-	}
-}
-
-func writeNotModified(w ResponseWriter) {
-	// RFC 7232 section 4.1:
-	// a sender SHOULD NOT generate representation metadata other than the
-	// above listed fields unless said metadata exists for the purpose of
-	// guiding cache updates (e.g., Last-Modified might be useful if the
-	// response does not have an ETag field).
-	h := w.Header()
-	delete(h, "Content-Type")
-	delete(h, "Content-Length")
-	if h.Get("Etag") != "" {
-		delete(h, "Last-Modified")
-	}
-	w.WriteHeader(StatusNotModified)
-}
-
-// checkPreconditions evaluates request preconditions and reports whether a precondition
-// resulted in sending StatusNotModified or StatusPreconditionFailed.
-func checkPreconditions(w ResponseWriter, r *Request, modtime time.Time) (done bool, rangeHeader string) {
-	// This function carefully follows RFC 7232 section 6.
-	ch := checkIfMatch(w, r)
-	if ch == condNone {
-		ch = checkIfUnmodifiedSince(r, modtime)
-	}
-	if ch == condFalse {
-		w.WriteHeader(StatusPreconditionFailed)
-		return true, ""
-	}
-	switch checkIfNoneMatch(w, r) {
-	case condFalse:
-		if r.Method == "GET" || r.Method == "HEAD" {
-			writeNotModified(w)
-			return true, ""
-		} else {
-			w.WriteHeader(StatusPreconditionFailed)
-			return true, ""
-		}
-	case condNone:
-		if checkIfModifiedSince(r, modtime) == condFalse {
-			writeNotModified(w)
-			return true, ""
-		}
-	}
-
-	rangeHeader = r.Header.get("Range")
-	if rangeHeader != "" && checkIfRange(w, r, modtime) == condFalse {
-		rangeHeader = ""
-	}
-	return false, rangeHeader
-}
-
-// name is '/'-separated, not filepath.Separator.
-func serveFile(w ResponseWriter, r *Request, fs FileSystem, name string, redirect bool) {
-	const indexPage = "/index.html"
-
-	// redirect .../index.html to .../
-	// can't use Redirect() because that would make the path absolute,
-	// which would be a problem running under StripPrefix
-	if strings.HasSuffix(r.URL.Path, indexPage) {
-		localRedirect(w, r, "./")
-		return
-	}
-
-	f, err := fs.Open(name)
-	if err != nil {
-		msg, code := toHTTPError(err)
-		Error(w, msg, code)
-		return
-	}
-	defer f.Close()
-
-	d, err := f.Stat()
-	if err != nil {
-		msg, code := toHTTPError(err)
-		Error(w, msg, code)
-		return
-	}
-
-	if redirect {
-		// redirect to canonical path: / at end of directory url
-		// r.URL.Path always begins with /
-		url := r.URL.Path
-		if d.IsDir() {
-			if url[len(url)-1] != '/' {
-				localRedirect(w, r, path.Base(url)+"/")
-				return
-			}
-		} else {
-			if url[len(url)-1] == '/' {
-				localRedirect(w, r, "../"+path.Base(url))
-				return
-			}
-		}
-	}
-
-	if d.IsDir() {
-		url := r.URL.Path
-		// redirect if the directory name doesn't end in a slash
-		if url == "" || url[len(url)-1] != '/' {
-			localRedirect(w, r, path.Base(url)+"/")
-			return
-		}
-
-		// use contents of index.html for directory, if present
-		index := strings.TrimSuffix(name, "/") + indexPage
-		ff, err := fs.Open(index)
-		if err == nil {
-			defer ff.Close()
-			dd, err := ff.Stat()
-			if err == nil {
-				name = index
-				d = dd
-				f = ff
-			}
-		}
-	}
-
-	// Still a directory? (we didn't find an index.html file)
-	if d.IsDir() {
-		if checkIfModifiedSince(r, d.ModTime()) == condFalse {
-			writeNotModified(w)
-			return
-		}
-		setLastModified(w, d.ModTime())
-		dirList(w, r, f)
-		return
-	}
-
-	// serveContent will check modification time
-	sizeFunc := func() (int64, error) { return d.Size(), nil }
-	serveContent(w, r, d.Name(), d.ModTime(), sizeFunc, f)
-}
-
-// toHTTPError returns a non-specific HTTP error message and status code
-// for a given non-nil error value. It's important that toHTTPError does not
-// actually return err.Error(), since msg and httpStatus are returned to users,
-// and historically Go's ServeContent always returned just "404 Not Found" for
-// all errors. We don't want to start leaking information in error messages.
-func toHTTPError(err error) (msg string, httpStatus int) {
-	if errors.Is(err, fs.ErrNotExist) {
-		return "404 page not found", StatusNotFound
-	}
-	if errors.Is(err, fs.ErrPermission) {
-		return "403 Forbidden", StatusForbidden
-	}
-	// Default:
-	return "500 Internal Server Error", StatusInternalServerError
-}
-
-// localRedirect gives a Moved Permanently response.
-// It does not convert relative paths to absolute paths like Redirect does.
-func localRedirect(w ResponseWriter, r *Request, newPath string) {
-	if q := r.URL.RawQuery; q != "" {
-		newPath += "?" + q
-	}
-	w.Header().Set("Location", newPath)
-	w.WriteHeader(StatusMovedPermanently)
-}
-
-// ServeFile replies to the request with the contents of the named
-// file or directory.
-//
-// If the provided file or directory name is a relative path, it is
-// interpreted relative to the current directory and may ascend to
-// parent directories. If the provided name is constructed from user
-// input, it should be sanitized before calling ServeFile.
-//
-// As a precaution, ServeFile will reject requests where r.URL.Path
-// contains a ".." path element; this protects against callers who
-// might unsafely use filepath.Join on r.URL.Path without sanitizing
-// it and then use that filepath.Join result as the name argument.
-//
-// As another special case, ServeFile redirects any request where r.URL.Path
-// ends in "/index.html" to the same path, without the final
-// "index.html". To avoid such redirects either modify the path or
-// use ServeContent.
-//
-// Outside of those two special cases, ServeFile does not use
-// r.URL.Path for selecting the file or directory to serve; only the
-// file or directory provided in the name argument is used.
-func ServeFile(w ResponseWriter, r *Request, name string) {
-	if containsDotDot(r.URL.Path) {
-		// Too many programs use r.URL.Path to construct the argument to
-		// serveFile. Reject the request under the assumption that happened
-		// here and ".." may not be wanted.
-		// Note that name might not contain "..", for example if code (still
-		// incorrectly) used filepath.Join(myDir, r.URL.Path).
-		Error(w, "invalid URL path", StatusBadRequest)
-		return
-	}
-	dir, file := filepath.Split(name)
-	serveFile(w, r, Dir(dir), file, false)
-}
-
-func containsDotDot(v string) bool {
-	if !strings.Contains(v, "..") {
-		return false
-	}
-	for _, ent := range strings.FieldsFunc(v, isSlashRune) {
-		if ent == ".." {
-			return true
-		}
-	}
-	return false
-}
-
-func isSlashRune(r rune) bool { return r == '/' || r == '\\' }
-
-type fileHandler struct {
-	root FileSystem
-}
-
-type ioFS struct {
-	fsys fs.FS
-}
-
-type ioFile struct {
-	file fs.File
-}
-
-func (f ioFS) Open(name string) (File, error) {
-	if name == "/" {
-		name = "."
-	} else {
-		name = strings.TrimPrefix(name, "/")
-	}
-	file, err := f.fsys.Open(name)
-	if err != nil {
-		return nil, mapOpenError(err, name, '/', func(path string) (fs.FileInfo, error) {
-			return fs.Stat(f.fsys, path)
-		})
-	}
-	return ioFile{file}, nil
-}
-
-func (f ioFile) Close() error               { return f.file.Close() }
-func (f ioFile) Read(b []byte) (int, error) { return f.file.Read(b) }
-func (f ioFile) Stat() (fs.FileInfo, error) { return f.file.Stat() }
-
-var errMissingSeek = errors.New("io.File missing Seek method")
-var errMissingReadDir = errors.New("io.File directory missing ReadDir method")
-
-func (f ioFile) Seek(offset int64, whence int) (int64, error) {
-	s, ok := f.file.(io.Seeker)
-	if !ok {
-		return 0, errMissingSeek
-	}
-	return s.Seek(offset, whence)
-}
-
-func (f ioFile) ReadDir(count int) ([]fs.DirEntry, error) {
-	d, ok := f.file.(fs.ReadDirFile)
-	if !ok {
-		return nil, errMissingReadDir
-	}
-	return d.ReadDir(count)
-}
-
-func (f ioFile) Readdir(count int) ([]fs.FileInfo, error) {
-	d, ok := f.file.(fs.ReadDirFile)
-	if !ok {
-		return nil, errMissingReadDir
-	}
-	var list []fs.FileInfo
-	for {
-		dirs, err := d.ReadDir(count - len(list))
-		for _, dir := range dirs {
-			info, err := dir.Info()
-			if err != nil {
-				// Pretend it doesn't exist, like (*os.File).Readdir does.
-				continue
-			}
-			list = append(list, info)
-		}
-		if err != nil {
-			return list, err
-		}
-		if count < 0 || len(list) >= count {
-			break
-		}
-	}
-	return list, nil
-}
-
-// FS converts fsys to a FileSystem implementation,
-// for use with FileServer and NewFileTransport.
-func FS(fsys fs.FS) FileSystem {
-	return ioFS{fsys}
-}
-
-// FileServer returns a handler that serves HTTP requests
-// with the contents of the file system rooted at root.
-//
-// As a special case, the returned file server redirects any request
-// ending in "/index.html" to the same path, without the final
-// "index.html".
-//
-// To use the operating system's file system implementation,
-// use http.Dir:
-//
-//     http.Handle("/", http.FileServer(http.Dir("/tmp")))
-//
-// To use an fs.FS implementation, use http.FS to convert it:
-//
-//	http.Handle("/", http.FileServer(http.FS(fsys)))
-//
-func FileServer(root FileSystem) Handler {
-	return &fileHandler{root}
-}
-
-func (f *fileHandler) ServeHTTP(w ResponseWriter, r *Request) {
-	upath := r.URL.Path
-	if !strings.HasPrefix(upath, "/") {
-		upath = "/" + upath
-		r.URL.Path = upath
-	}
-	serveFile(w, r, f.root, path.Clean(upath), true)
-}
-
-// httpRange specifies the byte range to be sent to the client.
-type httpRange struct {
-	start, length int64
-}
-
-func (r httpRange) contentRange(size int64) string {
-	return fmt.Sprintf("bytes %d-%d/%d", r.start, r.start+r.length-1, size)
-}
-
-func (r httpRange) mimeHeader(contentType string, size int64) textproto.MIMEHeader {
-	return textproto.MIMEHeader{
-		"Content-Range": {r.contentRange(size)},
-		"Content-Type":  {contentType},
-	}
-}
-
-// parseRange parses a Range header string as per RFC 7233.
-// errNoOverlap is returned if none of the ranges overlap.
-func parseRange(s string, size int64) ([]httpRange, error) {
-	if s == "" {
-		return nil, nil // header not present
-	}
-	const b = "bytes="
-	if !strings.HasPrefix(s, b) {
-		return nil, errors.New("invalid range")
-	}
-	var ranges []httpRange
-	noOverlap := false
-	for _, ra := range strings.Split(s[len(b):], ",") {
-		ra = textproto.TrimString(ra)
-		if ra == "" {
-			continue
-		}
-		start, end, ok := strings.Cut(ra, "-")
-		if !ok {
-			return nil, errors.New("invalid range")
-		}
-		start, end = textproto.TrimString(start), textproto.TrimString(end)
-		var r httpRange
-		if start == "" {
-			// If no start is specified, end specifies the
-			// range start relative to the end of the file,
-			// and we are dealing with <suffix-length>
-			// which has to be a non-negative integer as per
-			// RFC 7233 Section 2.1 "Byte-Ranges".
-			if end == "" || end[0] == '-' {
-				return nil, errors.New("invalid range")
-			}
-			i, err := strconv.ParseInt(end, 10, 64)
-			if i < 0 || err != nil {
-				return nil, errors.New("invalid range")
-			}
-			if i > size {
-				i = size
-			}
-			r.start = size - i
-			r.length = size - r.start
-		} else {
-			i, err := strconv.ParseInt(start, 10, 64)
-			if err != nil || i < 0 {
-				return nil, errors.New("invalid range")
-			}
-			if i >= size {
-				// If the range begins after the size of the content,
-				// then it does not overlap.
-				noOverlap = true
-				continue
-			}
-			r.start = i
-			if end == "" {
-				// If no end is specified, range extends to end of the file.
-				r.length = size - r.start
-			} else {
-				i, err := strconv.ParseInt(end, 10, 64)
-				if err != nil || r.start > i {
-					return nil, errors.New("invalid range")
-				}
-				if i >= size {
-					i = size - 1
-				}
-				r.length = i - r.start + 1
-			}
-		}
-		ranges = append(ranges, r)
-	}
-	if noOverlap && len(ranges) == 0 {
-		// The specified ranges did not overlap with the content.
-		return nil, errNoOverlap
-	}
-	return ranges, nil
-}
-
-// countingWriter counts how many bytes have been written to it.
-type countingWriter int64
-
-func (w *countingWriter) Write(p []byte) (n int, err error) {
-	*w += countingWriter(len(p))
-	return len(p), nil
-}
-
-// rangesMIMESize returns the number of bytes it takes to encode the
-// provided ranges as a multipart response.
-func rangesMIMESize(ranges []httpRange, contentType string, contentSize int64) (encSize int64) {
-	var w countingWriter
-	mw := multipart.NewWriter(&w)
-	for _, ra := range ranges {
-		mw.CreatePart(ra.mimeHeader(contentType, contentSize))
-		encSize += ra.length
-	}
-	mw.Close()
-	encSize += int64(w)
-	return
-}
-
-func sumRangesSize(ranges []httpRange) (size int64) {
-	for _, ra := range ranges {
-		size += ra.length
-	}
-	return
-}
diff --git a/contrib/go/_std_1.18/src/net/http/h2_bundle.go b/contrib/go/_std_1.18/src/net/http/h2_bundle.go
deleted file mode 100644
index bb82f24585..0000000000
--- a/contrib/go/_std_1.18/src/net/http/h2_bundle.go
+++ /dev/null
@@ -1,10858 +0,0 @@
-//go:build !nethttpomithttp2
-// +build !nethttpomithttp2
-
-// Code generated by golang.org/x/tools/cmd/bundle. DO NOT EDIT.
-//   $ bundle -o=h2_bundle.go -prefix=http2 -tags=!nethttpomithttp2 golang.org/x/net/http2
-
-// Package http2 implements the HTTP/2 protocol.
-//
-// This package is low-level and intended to be used directly by very
-// few people. Most users will use it indirectly through the automatic
-// use by the net/http package (from Go 1.6 and later).
-// For use in earlier Go versions see ConfigureServer. (Transport support
-// requires Go 1.6 or later)
-//
-// See https://http2.github.io/ for more information on HTTP/2.
-//
-// See https://http2.golang.org/ for a test server running this code.
-//
-
-package http
-
-import (
-	"bufio"
-	"bytes"
-	"compress/gzip"
-	"context"
-	"crypto/rand"
-	"crypto/tls"
-	"encoding/binary"
-	"errors"
-	"fmt"
-	"io"
-	"io/ioutil"
-	"log"
-	"math"
-	mathrand "math/rand"
-	"net"
-	"net/http/httptrace"
-	"net/textproto"
-	"net/url"
-	"os"
-	"reflect"
-	"runtime"
-	"sort"
-	"strconv"
-	"strings"
-	"sync"
-	"sync/atomic"
-	"time"
-
-	"golang.org/x/net/http/httpguts"
-	"golang.org/x/net/http2/hpack"
-	"golang.org/x/net/idna"
-)
-
-// The HTTP protocols are defined in terms of ASCII, not Unicode. This file
-// contains helper functions which may use Unicode-aware functions which would
-// otherwise be unsafe and could introduce vulnerabilities if used improperly.
-
-// asciiEqualFold is strings.EqualFold, ASCII only. It reports whether s and t
-// are equal, ASCII-case-insensitively.
-func http2asciiEqualFold(s, t string) bool {
-	if len(s) != len(t) {
-		return false
-	}
-	for i := 0; i < len(s); i++ {
-		if http2lower(s[i]) != http2lower(t[i]) {
-			return false
-		}
-	}
-	return true
-}
-
-// lower returns the ASCII lowercase version of b.
-func http2lower(b byte) byte {
-	if 'A' <= b && b <= 'Z' {
-		return b + ('a' - 'A')
-	}
-	return b
-}
-
-// isASCIIPrint returns whether s is ASCII and printable according to
-// https://tools.ietf.org/html/rfc20#section-4.2.
-func http2isASCIIPrint(s string) bool {
-	for i := 0; i < len(s); i++ {
-		if s[i] < ' ' || s[i] > '~' {
-			return false
-		}
-	}
-	return true
-}
-
-// asciiToLower returns the lowercase version of s if s is ASCII and printable,
-// and whether or not it was.
-func http2asciiToLower(s string) (lower string, ok bool) {
-	if !http2isASCIIPrint(s) {
-		return "", false
-	}
-	return strings.ToLower(s), true
-}
-
-// A list of the possible cipher suite ids. Taken from
-// https://www.iana.org/assignments/tls-parameters/tls-parameters.txt
-
-const (
-	http2cipher_TLS_NULL_WITH_NULL_NULL               uint16 = 0x0000
-	http2cipher_TLS_RSA_WITH_NULL_MD5                 uint16 = 0x0001
-	http2cipher_TLS_RSA_WITH_NULL_SHA                 uint16 = 0x0002
-	http2cipher_TLS_RSA_EXPORT_WITH_RC4_40_MD5        uint16 = 0x0003
-	http2cipher_TLS_RSA_WITH_RC4_128_MD5              uint16 = 0x0004
-	http2cipher_TLS_RSA_WITH_RC4_128_SHA              uint16 = 0x0005
-	http2cipher_TLS_RSA_EXPORT_WITH_RC2_CBC_40_MD5    uint16 = 0x0006
-	http2cipher_TLS_RSA_WITH_IDEA_CBC_SHA             uint16 = 0x0007
-	http2cipher_TLS_RSA_EXPORT_WITH_DES40_CBC_SHA     uint16 = 0x0008
-	http2cipher_TLS_RSA_WITH_DES_CBC_SHA              uint16 = 0x0009
-	http2cipher_TLS_RSA_WITH_3DES_EDE_CBC_SHA         uint16 = 0x000A
-	http2cipher_TLS_DH_DSS_EXPORT_WITH_DES40_CBC_SHA  uint16 = 0x000B
-	http2cipher_TLS_DH_DSS_WITH_DES_CBC_SHA           uint16 = 0x000C
-	http2cipher_TLS_DH_DSS_WITH_3DES_EDE_CBC_SHA      uint16 = 0x000D
-	http2cipher_TLS_DH_RSA_EXPORT_WITH_DES40_CBC_SHA  uint16 = 0x000E
-	http2cipher_TLS_DH_RSA_WITH_DES_CBC_SHA           uint16 = 0x000F
-	http2cipher_TLS_DH_RSA_WITH_3DES_EDE_CBC_SHA      uint16 = 0x0010
-	http2cipher_TLS_DHE_DSS_EXPORT_WITH_DES40_CBC_SHA uint16 = 0x0011
-	http2cipher_TLS_DHE_DSS_WITH_DES_CBC_SHA          uint16 = 0x0012
-	http2cipher_TLS_DHE_DSS_WITH_3DES_EDE_CBC_SHA     uint16 = 0x0013
-	http2cipher_TLS_DHE_RSA_EXPORT_WITH_DES40_CBC_SHA uint16 = 0x0014
-	http2cipher_TLS_DHE_RSA_WITH_DES_CBC_SHA          uint16 = 0x0015
-	http2cipher_TLS_DHE_RSA_WITH_3DES_EDE_CBC_SHA     uint16 = 0x0016
-	http2cipher_TLS_DH_anon_EXPORT_WITH_RC4_40_MD5    uint16 = 0x0017
-	http2cipher_TLS_DH_anon_WITH_RC4_128_MD5          uint16 = 0x0018
-	http2cipher_TLS_DH_anon_EXPORT_WITH_DES40_CBC_SHA uint16 = 0x0019
-	http2cipher_TLS_DH_anon_WITH_DES_CBC_SHA          uint16 = 0x001A
-	http2cipher_TLS_DH_anon_WITH_3DES_EDE_CBC_SHA     uint16 = 0x001B
-	// Reserved uint16 =  0x001C-1D
-	http2cipher_TLS_KRB5_WITH_DES_CBC_SHA             uint16 = 0x001E
-	http2cipher_TLS_KRB5_WITH_3DES_EDE_CBC_SHA        uint16 = 0x001F
-	http2cipher_TLS_KRB5_WITH_RC4_128_SHA             uint16 = 0x0020
-	http2cipher_TLS_KRB5_WITH_IDEA_CBC_SHA            uint16 = 0x0021
-	http2cipher_TLS_KRB5_WITH_DES_CBC_MD5             uint16 = 0x0022
-	http2cipher_TLS_KRB5_WITH_3DES_EDE_CBC_MD5        uint16 = 0x0023
-	http2cipher_TLS_KRB5_WITH_RC4_128_MD5             uint16 = 0x0024
-	http2cipher_TLS_KRB5_WITH_IDEA_CBC_MD5            uint16 = 0x0025
-	http2cipher_TLS_KRB5_EXPORT_WITH_DES_CBC_40_SHA   uint16 = 0x0026
-	http2cipher_TLS_KRB5_EXPORT_WITH_RC2_CBC_40_SHA   uint16 = 0x0027
-	http2cipher_TLS_KRB5_EXPORT_WITH_RC4_40_SHA       uint16 = 0x0028
-	http2cipher_TLS_KRB5_EXPORT_WITH_DES_CBC_40_MD5   uint16 = 0x0029
-	http2cipher_TLS_KRB5_EXPORT_WITH_RC2_CBC_40_MD5   uint16 = 0x002A
-	http2cipher_TLS_KRB5_EXPORT_WITH_RC4_40_MD5       uint16 = 0x002B
-	http2cipher_TLS_PSK_WITH_NULL_SHA                 uint16 = 0x002C
-	http2cipher_TLS_DHE_PSK_WITH_NULL_SHA             uint16 = 0x002D
-	http2cipher_TLS_RSA_PSK_WITH_NULL_SHA             uint16 = 0x002E
-	http2cipher_TLS_RSA_WITH_AES_128_CBC_SHA          uint16 = 0x002F
-	http2cipher_TLS_DH_DSS_WITH_AES_128_CBC_SHA       uint16 = 0x0030
-	http2cipher_TLS_DH_RSA_WITH_AES_128_CBC_SHA       uint16 = 0x0031
-	http2cipher_TLS_DHE_DSS_WITH_AES_128_CBC_SHA      uint16 = 0x0032
-	http2cipher_TLS_DHE_RSA_WITH_AES_128_CBC_SHA      uint16 = 0x0033
-	http2cipher_TLS_DH_anon_WITH_AES_128_CBC_SHA      uint16 = 0x0034
-	http2cipher_TLS_RSA_WITH_AES_256_CBC_SHA          uint16 = 0x0035
-	http2cipher_TLS_DH_DSS_WITH_AES_256_CBC_SHA       uint16 = 0x0036
-	http2cipher_TLS_DH_RSA_WITH_AES_256_CBC_SHA       uint16 = 0x0037
-	http2cipher_TLS_DHE_DSS_WITH_AES_256_CBC_SHA      uint16 = 0x0038
-	http2cipher_TLS_DHE_RSA_WITH_AES_256_CBC_SHA      uint16 = 0x0039
-	http2cipher_TLS_DH_anon_WITH_AES_256_CBC_SHA      uint16 = 0x003A
-	http2cipher_TLS_RSA_WITH_NULL_SHA256              uint16 = 0x003B
-	http2cipher_TLS_RSA_WITH_AES_128_CBC_SHA256       uint16 = 0x003C
-	http2cipher_TLS_RSA_WITH_AES_256_CBC_SHA256       uint16 = 0x003D
-	http2cipher_TLS_DH_DSS_WITH_AES_128_CBC_SHA256    uint16 = 0x003E
-	http2cipher_TLS_DH_RSA_WITH_AES_128_CBC_SHA256    uint16 = 0x003F
-	http2cipher_TLS_DHE_DSS_WITH_AES_128_CBC_SHA256   uint16 = 0x0040
-	http2cipher_TLS_RSA_WITH_CAMELLIA_128_CBC_SHA     uint16 = 0x0041
-	http2cipher_TLS_DH_DSS_WITH_CAMELLIA_128_CBC_SHA  uint16 = 0x0042
-	http2cipher_TLS_DH_RSA_WITH_CAMELLIA_128_CBC_SHA  uint16 = 0x0043
-	http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_128_CBC_SHA uint16 = 0x0044
-	http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_128_CBC_SHA uint16 = 0x0045
-	http2cipher_TLS_DH_anon_WITH_CAMELLIA_128_CBC_SHA uint16 = 0x0046
-	// Reserved uint16 =  0x0047-4F
-	// Reserved uint16 =  0x0050-58
-	// Reserved uint16 =  0x0059-5C
-	// Unassigned uint16 =  0x005D-5F
-	// Reserved uint16 =  0x0060-66
-	http2cipher_TLS_DHE_RSA_WITH_AES_128_CBC_SHA256 uint16 = 0x0067
-	http2cipher_TLS_DH_DSS_WITH_AES_256_CBC_SHA256  uint16 = 0x0068
-	http2cipher_TLS_DH_RSA_WITH_AES_256_CBC_SHA256  uint16 = 0x0069
-	http2cipher_TLS_DHE_DSS_WITH_AES_256_CBC_SHA256 uint16 = 0x006A
-	http2cipher_TLS_DHE_RSA_WITH_AES_256_CBC_SHA256 uint16 = 0x006B
-	http2cipher_TLS_DH_anon_WITH_AES_128_CBC_SHA256 uint16 = 0x006C
-	http2cipher_TLS_DH_anon_WITH_AES_256_CBC_SHA256 uint16 = 0x006D
-	// Unassigned uint16 =  0x006E-83
-	http2cipher_TLS_RSA_WITH_CAMELLIA_256_CBC_SHA        uint16 = 0x0084
-	http2cipher_TLS_DH_DSS_WITH_CAMELLIA_256_CBC_SHA     uint16 = 0x0085
-	http2cipher_TLS_DH_RSA_WITH_CAMELLIA_256_CBC_SHA     uint16 = 0x0086
-	http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_256_CBC_SHA    uint16 = 0x0087
-	http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_256_CBC_SHA    uint16 = 0x0088
-	http2cipher_TLS_DH_anon_WITH_CAMELLIA_256_CBC_SHA    uint16 = 0x0089
-	http2cipher_TLS_PSK_WITH_RC4_128_SHA                 uint16 = 0x008A
-	http2cipher_TLS_PSK_WITH_3DES_EDE_CBC_SHA            uint16 = 0x008B
-	http2cipher_TLS_PSK_WITH_AES_128_CBC_SHA             uint16 = 0x008C
-	http2cipher_TLS_PSK_WITH_AES_256_CBC_SHA             uint16 = 0x008D
-	http2cipher_TLS_DHE_PSK_WITH_RC4_128_SHA             uint16 = 0x008E
-	http2cipher_TLS_DHE_PSK_WITH_3DES_EDE_CBC_SHA        uint16 = 0x008F
-	http2cipher_TLS_DHE_PSK_WITH_AES_128_CBC_SHA         uint16 = 0x0090
-	http2cipher_TLS_DHE_PSK_WITH_AES_256_CBC_SHA         uint16 = 0x0091
-	http2cipher_TLS_RSA_PSK_WITH_RC4_128_SHA             uint16 = 0x0092
-	http2cipher_TLS_RSA_PSK_WITH_3DES_EDE_CBC_SHA        uint16 = 0x0093
-	http2cipher_TLS_RSA_PSK_WITH_AES_128_CBC_SHA         uint16 = 0x0094
-	http2cipher_TLS_RSA_PSK_WITH_AES_256_CBC_SHA         uint16 = 0x0095
-	http2cipher_TLS_RSA_WITH_SEED_CBC_SHA                uint16 = 0x0096
-	http2cipher_TLS_DH_DSS_WITH_SEED_CBC_SHA             uint16 = 0x0097
-	http2cipher_TLS_DH_RSA_WITH_SEED_CBC_SHA             uint16 = 0x0098
-	http2cipher_TLS_DHE_DSS_WITH_SEED_CBC_SHA            uint16 = 0x0099
-	http2cipher_TLS_DHE_RSA_WITH_SEED_CBC_SHA            uint16 = 0x009A
-	http2cipher_TLS_DH_anon_WITH_SEED_CBC_SHA            uint16 = 0x009B
-	http2cipher_TLS_RSA_WITH_AES_128_GCM_SHA256          uint16 = 0x009C
-	http2cipher_TLS_RSA_WITH_AES_256_GCM_SHA384          uint16 = 0x009D
-	http2cipher_TLS_DHE_RSA_WITH_AES_128_GCM_SHA256      uint16 = 0x009E
-	http2cipher_TLS_DHE_RSA_WITH_AES_256_GCM_SHA384      uint16 = 0x009F
-	http2cipher_TLS_DH_RSA_WITH_AES_128_GCM_SHA256       uint16 = 0x00A0
-	http2cipher_TLS_DH_RSA_WITH_AES_256_GCM_SHA384       uint16 = 0x00A1
-	http2cipher_TLS_DHE_DSS_WITH_AES_128_GCM_SHA256      uint16 = 0x00A2
-	http2cipher_TLS_DHE_DSS_WITH_AES_256_GCM_SHA384      uint16 = 0x00A3
-	http2cipher_TLS_DH_DSS_WITH_AES_128_GCM_SHA256       uint16 = 0x00A4
-	http2cipher_TLS_DH_DSS_WITH_AES_256_GCM_SHA384       uint16 = 0x00A5
-	http2cipher_TLS_DH_anon_WITH_AES_128_GCM_SHA256      uint16 = 0x00A6
-	http2cipher_TLS_DH_anon_WITH_AES_256_GCM_SHA384      uint16 = 0x00A7
-	http2cipher_TLS_PSK_WITH_AES_128_GCM_SHA256          uint16 = 0x00A8
-	http2cipher_TLS_PSK_WITH_AES_256_GCM_SHA384          uint16 = 0x00A9
-	http2cipher_TLS_DHE_PSK_WITH_AES_128_GCM_SHA256      uint16 = 0x00AA
-	http2cipher_TLS_DHE_PSK_WITH_AES_256_GCM_SHA384      uint16 = 0x00AB
-	http2cipher_TLS_RSA_PSK_WITH_AES_128_GCM_SHA256      uint16 = 0x00AC
-	http2cipher_TLS_RSA_PSK_WITH_AES_256_GCM_SHA384      uint16 = 0x00AD
-	http2cipher_TLS_PSK_WITH_AES_128_CBC_SHA256          uint16 = 0x00AE
-	http2cipher_TLS_PSK_WITH_AES_256_CBC_SHA384          uint16 = 0x00AF
-	http2cipher_TLS_PSK_WITH_NULL_SHA256                 uint16 = 0x00B0
-	http2cipher_TLS_PSK_WITH_NULL_SHA384                 uint16 = 0x00B1
-	http2cipher_TLS_DHE_PSK_WITH_AES_128_CBC_SHA256      uint16 = 0x00B2
-	http2cipher_TLS_DHE_PSK_WITH_AES_256_CBC_SHA384      uint16 = 0x00B3
-	http2cipher_TLS_DHE_PSK_WITH_NULL_SHA256             uint16 = 0x00B4
-	http2cipher_TLS_DHE_PSK_WITH_NULL_SHA384             uint16 = 0x00B5
-	http2cipher_TLS_RSA_PSK_WITH_AES_128_CBC_SHA256      uint16 = 0x00B6
-	http2cipher_TLS_RSA_PSK_WITH_AES_256_CBC_SHA384      uint16 = 0x00B7
-	http2cipher_TLS_RSA_PSK_WITH_NULL_SHA256             uint16 = 0x00B8
-	http2cipher_TLS_RSA_PSK_WITH_NULL_SHA384             uint16 = 0x00B9
-	http2cipher_TLS_RSA_WITH_CAMELLIA_128_CBC_SHA256     uint16 = 0x00BA
-	http2cipher_TLS_DH_DSS_WITH_CAMELLIA_128_CBC_SHA256  uint16 = 0x00BB
-	http2cipher_TLS_DH_RSA_WITH_CAMELLIA_128_CBC_SHA256  uint16 = 0x00BC
-	http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_128_CBC_SHA256 uint16 = 0x00BD
-	http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_128_CBC_SHA256 uint16 = 0x00BE
-	http2cipher_TLS_DH_anon_WITH_CAMELLIA_128_CBC_SHA256 uint16 = 0x00BF
-	http2cipher_TLS_RSA_WITH_CAMELLIA_256_CBC_SHA256     uint16 = 0x00C0
-	http2cipher_TLS_DH_DSS_WITH_CAMELLIA_256_CBC_SHA256  uint16 = 0x00C1
-	http2cipher_TLS_DH_RSA_WITH_CAMELLIA_256_CBC_SHA256  uint16 = 0x00C2
-	http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_256_CBC_SHA256 uint16 = 0x00C3
-	http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_256_CBC_SHA256 uint16 = 0x00C4
-	http2cipher_TLS_DH_anon_WITH_CAMELLIA_256_CBC_SHA256 uint16 = 0x00C5
-	// Unassigned uint16 =  0x00C6-FE
-	http2cipher_TLS_EMPTY_RENEGOTIATION_INFO_SCSV uint16 = 0x00FF
-	// Unassigned uint16 =  0x01-55,*
-	http2cipher_TLS_FALLBACK_SCSV uint16 = 0x5600
-	// Unassigned                                   uint16 = 0x5601 - 0xC000
-	http2cipher_TLS_ECDH_ECDSA_WITH_NULL_SHA                 uint16 = 0xC001
-	http2cipher_TLS_ECDH_ECDSA_WITH_RC4_128_SHA              uint16 = 0xC002
-	http2cipher_TLS_ECDH_ECDSA_WITH_3DES_EDE_CBC_SHA         uint16 = 0xC003
-	http2cipher_TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA          uint16 = 0xC004
-	http2cipher_TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA          uint16 = 0xC005
-	http2cipher_TLS_ECDHE_ECDSA_WITH_NULL_SHA                uint16 = 0xC006
-	http2cipher_TLS_ECDHE_ECDSA_WITH_RC4_128_SHA             uint16 = 0xC007
-	http2cipher_TLS_ECDHE_ECDSA_WITH_3DES_EDE_CBC_SHA        uint16 = 0xC008
-	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA         uint16 = 0xC009
-	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA         uint16 = 0xC00A
-	http2cipher_TLS_ECDH_RSA_WITH_NULL_SHA                   uint16 = 0xC00B
-	http2cipher_TLS_ECDH_RSA_WITH_RC4_128_SHA                uint16 = 0xC00C
-	http2cipher_TLS_ECDH_RSA_WITH_3DES_EDE_CBC_SHA           uint16 = 0xC00D
-	http2cipher_TLS_ECDH_RSA_WITH_AES_128_CBC_SHA            uint16 = 0xC00E
-	http2cipher_TLS_ECDH_RSA_WITH_AES_256_CBC_SHA            uint16 = 0xC00F
-	http2cipher_TLS_ECDHE_RSA_WITH_NULL_SHA                  uint16 = 0xC010
-	http2cipher_TLS_ECDHE_RSA_WITH_RC4_128_SHA               uint16 = 0xC011
-	http2cipher_TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA          uint16 = 0xC012
-	http2cipher_TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA           uint16 = 0xC013
-	http2cipher_TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA           uint16 = 0xC014
-	http2cipher_TLS_ECDH_anon_WITH_NULL_SHA                  uint16 = 0xC015
-	http2cipher_TLS_ECDH_anon_WITH_RC4_128_SHA               uint16 = 0xC016
-	http2cipher_TLS_ECDH_anon_WITH_3DES_EDE_CBC_SHA          uint16 = 0xC017
-	http2cipher_TLS_ECDH_anon_WITH_AES_128_CBC_SHA           uint16 = 0xC018
-	http2cipher_TLS_ECDH_anon_WITH_AES_256_CBC_SHA           uint16 = 0xC019
-	http2cipher_TLS_SRP_SHA_WITH_3DES_EDE_CBC_SHA            uint16 = 0xC01A
-	http2cipher_TLS_SRP_SHA_RSA_WITH_3DES_EDE_CBC_SHA        uint16 = 0xC01B
-	http2cipher_TLS_SRP_SHA_DSS_WITH_3DES_EDE_CBC_SHA        uint16 = 0xC01C
-	http2cipher_TLS_SRP_SHA_WITH_AES_128_CBC_SHA             uint16 = 0xC01D
-	http2cipher_TLS_SRP_SHA_RSA_WITH_AES_128_CBC_SHA         uint16 = 0xC01E
-	http2cipher_TLS_SRP_SHA_DSS_WITH_AES_128_CBC_SHA         uint16 = 0xC01F
-	http2cipher_TLS_SRP_SHA_WITH_AES_256_CBC_SHA             uint16 = 0xC020
-	http2cipher_TLS_SRP_SHA_RSA_WITH_AES_256_CBC_SHA         uint16 = 0xC021
-	http2cipher_TLS_SRP_SHA_DSS_WITH_AES_256_CBC_SHA         uint16 = 0xC022
-	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256      uint16 = 0xC023
-	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384      uint16 = 0xC024
-	http2cipher_TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA256       uint16 = 0xC025
-	http2cipher_TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA384       uint16 = 0xC026
-	http2cipher_TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256        uint16 = 0xC027
-	http2cipher_TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384        uint16 = 0xC028
-	http2cipher_TLS_ECDH_RSA_WITH_AES_128_CBC_SHA256         uint16 = 0xC029
-	http2cipher_TLS_ECDH_RSA_WITH_AES_256_CBC_SHA384         uint16 = 0xC02A
-	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256      uint16 = 0xC02B
-	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384      uint16 = 0xC02C
-	http2cipher_TLS_ECDH_ECDSA_WITH_AES_128_GCM_SHA256       uint16 = 0xC02D
-	http2cipher_TLS_ECDH_ECDSA_WITH_AES_256_GCM_SHA384       uint16 = 0xC02E
-	http2cipher_TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256        uint16 = 0xC02F
-	http2cipher_TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384        uint16 = 0xC030
-	http2cipher_TLS_ECDH_RSA_WITH_AES_128_GCM_SHA256         uint16 = 0xC031
-	http2cipher_TLS_ECDH_RSA_WITH_AES_256_GCM_SHA384         uint16 = 0xC032
-	http2cipher_TLS_ECDHE_PSK_WITH_RC4_128_SHA               uint16 = 0xC033
-	http2cipher_TLS_ECDHE_PSK_WITH_3DES_EDE_CBC_SHA          uint16 = 0xC034
-	http2cipher_TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA           uint16 = 0xC035
-	http2cipher_TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA           uint16 = 0xC036
-	http2cipher_TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA256        uint16 = 0xC037
-	http2cipher_TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA384        uint16 = 0xC038
-	http2cipher_TLS_ECDHE_PSK_WITH_NULL_SHA                  uint16 = 0xC039
-	http2cipher_TLS_ECDHE_PSK_WITH_NULL_SHA256               uint16 = 0xC03A
-	http2cipher_TLS_ECDHE_PSK_WITH_NULL_SHA384               uint16 = 0xC03B
-	http2cipher_TLS_RSA_WITH_ARIA_128_CBC_SHA256             uint16 = 0xC03C
-	http2cipher_TLS_RSA_WITH_ARIA_256_CBC_SHA384             uint16 = 0xC03D
-	http2cipher_TLS_DH_DSS_WITH_ARIA_128_CBC_SHA256          uint16 = 0xC03E
-	http2cipher_TLS_DH_DSS_WITH_ARIA_256_CBC_SHA384          uint16 = 0xC03F
-	http2cipher_TLS_DH_RSA_WITH_ARIA_128_CBC_SHA256          uint16 = 0xC040
-	http2cipher_TLS_DH_RSA_WITH_ARIA_256_CBC_SHA384          uint16 = 0xC041
-	http2cipher_TLS_DHE_DSS_WITH_ARIA_128_CBC_SHA256         uint16 = 0xC042
-	http2cipher_TLS_DHE_DSS_WITH_ARIA_256_CBC_SHA384         uint16 = 0xC043
-	http2cipher_TLS_DHE_RSA_WITH_ARIA_128_CBC_SHA256         uint16 = 0xC044
-	http2cipher_TLS_DHE_RSA_WITH_ARIA_256_CBC_SHA384         uint16 = 0xC045
-	http2cipher_TLS_DH_anon_WITH_ARIA_128_CBC_SHA256         uint16 = 0xC046
-	http2cipher_TLS_DH_anon_WITH_ARIA_256_CBC_SHA384         uint16 = 0xC047
-	http2cipher_TLS_ECDHE_ECDSA_WITH_ARIA_128_CBC_SHA256     uint16 = 0xC048
-	http2cipher_TLS_ECDHE_ECDSA_WITH_ARIA_256_CBC_SHA384     uint16 = 0xC049
-	http2cipher_TLS_ECDH_ECDSA_WITH_ARIA_128_CBC_SHA256      uint16 = 0xC04A
-	http2cipher_TLS_ECDH_ECDSA_WITH_ARIA_256_CBC_SHA384      uint16 = 0xC04B
-	http2cipher_TLS_ECDHE_RSA_WITH_ARIA_128_CBC_SHA256       uint16 = 0xC04C
-	http2cipher_TLS_ECDHE_RSA_WITH_ARIA_256_CBC_SHA384       uint16 = 0xC04D
-	http2cipher_TLS_ECDH_RSA_WITH_ARIA_128_CBC_SHA256        uint16 = 0xC04E
-	http2cipher_TLS_ECDH_RSA_WITH_ARIA_256_CBC_SHA384        uint16 = 0xC04F
-	http2cipher_TLS_RSA_WITH_ARIA_128_GCM_SHA256             uint16 = 0xC050
-	http2cipher_TLS_RSA_WITH_ARIA_256_GCM_SHA384             uint16 = 0xC051
-	http2cipher_TLS_DHE_RSA_WITH_ARIA_128_GCM_SHA256         uint16 = 0xC052
-	http2cipher_TLS_DHE_RSA_WITH_ARIA_256_GCM_SHA384         uint16 = 0xC053
-	http2cipher_TLS_DH_RSA_WITH_ARIA_128_GCM_SHA256          uint16 = 0xC054
-	http2cipher_TLS_DH_RSA_WITH_ARIA_256_GCM_SHA384          uint16 = 0xC055
-	http2cipher_TLS_DHE_DSS_WITH_ARIA_128_GCM_SHA256         uint16 = 0xC056
-	http2cipher_TLS_DHE_DSS_WITH_ARIA_256_GCM_SHA384         uint16 = 0xC057
-	http2cipher_TLS_DH_DSS_WITH_ARIA_128_GCM_SHA256          uint16 = 0xC058
-	http2cipher_TLS_DH_DSS_WITH_ARIA_256_GCM_SHA384          uint16 = 0xC059
-	http2cipher_TLS_DH_anon_WITH_ARIA_128_GCM_SHA256         uint16 = 0xC05A
-	http2cipher_TLS_DH_anon_WITH_ARIA_256_GCM_SHA384         uint16 = 0xC05B
-	http2cipher_TLS_ECDHE_ECDSA_WITH_ARIA_128_GCM_SHA256     uint16 = 0xC05C
-	http2cipher_TLS_ECDHE_ECDSA_WITH_ARIA_256_GCM_SHA384     uint16 = 0xC05D
-	http2cipher_TLS_ECDH_ECDSA_WITH_ARIA_128_GCM_SHA256      uint16 = 0xC05E
-	http2cipher_TLS_ECDH_ECDSA_WITH_ARIA_256_GCM_SHA384      uint16 = 0xC05F
-	http2cipher_TLS_ECDHE_RSA_WITH_ARIA_128_GCM_SHA256       uint16 = 0xC060
-	http2cipher_TLS_ECDHE_RSA_WITH_ARIA_256_GCM_SHA384       uint16 = 0xC061
-	http2cipher_TLS_ECDH_RSA_WITH_ARIA_128_GCM_SHA256        uint16 = 0xC062
-	http2cipher_TLS_ECDH_RSA_WITH_ARIA_256_GCM_SHA384        uint16 = 0xC063
-	http2cipher_TLS_PSK_WITH_ARIA_128_CBC_SHA256             uint16 = 0xC064
-	http2cipher_TLS_PSK_WITH_ARIA_256_CBC_SHA384             uint16 = 0xC065
-	http2cipher_TLS_DHE_PSK_WITH_ARIA_128_CBC_SHA256         uint16 = 0xC066
-	http2cipher_TLS_DHE_PSK_WITH_ARIA_256_CBC_SHA384         uint16 = 0xC067
-	http2cipher_TLS_RSA_PSK_WITH_ARIA_128_CBC_SHA256         uint16 = 0xC068
-	http2cipher_TLS_RSA_PSK_WITH_ARIA_256_CBC_SHA384         uint16 = 0xC069
-	http2cipher_TLS_PSK_WITH_ARIA_128_GCM_SHA256             uint16 = 0xC06A
-	http2cipher_TLS_PSK_WITH_ARIA_256_GCM_SHA384             uint16 = 0xC06B
-	http2cipher_TLS_DHE_PSK_WITH_ARIA_128_GCM_SHA256         uint16 = 0xC06C
-	http2cipher_TLS_DHE_PSK_WITH_ARIA_256_GCM_SHA384         uint16 = 0xC06D
-	http2cipher_TLS_RSA_PSK_WITH_ARIA_128_GCM_SHA256         uint16 = 0xC06E
-	http2cipher_TLS_RSA_PSK_WITH_ARIA_256_GCM_SHA384         uint16 = 0xC06F
-	http2cipher_TLS_ECDHE_PSK_WITH_ARIA_128_CBC_SHA256       uint16 = 0xC070
-	http2cipher_TLS_ECDHE_PSK_WITH_ARIA_256_CBC_SHA384       uint16 = 0xC071
-	http2cipher_TLS_ECDHE_ECDSA_WITH_CAMELLIA_128_CBC_SHA256 uint16 = 0xC072
-	http2cipher_TLS_ECDHE_ECDSA_WITH_CAMELLIA_256_CBC_SHA384 uint16 = 0xC073
-	http2cipher_TLS_ECDH_ECDSA_WITH_CAMELLIA_128_CBC_SHA256  uint16 = 0xC074
-	http2cipher_TLS_ECDH_ECDSA_WITH_CAMELLIA_256_CBC_SHA384  uint16 = 0xC075
-	http2cipher_TLS_ECDHE_RSA_WITH_CAMELLIA_128_CBC_SHA256   uint16 = 0xC076
-	http2cipher_TLS_ECDHE_RSA_WITH_CAMELLIA_256_CBC_SHA384   uint16 = 0xC077
-	http2cipher_TLS_ECDH_RSA_WITH_CAMELLIA_128_CBC_SHA256    uint16 = 0xC078
-	http2cipher_TLS_ECDH_RSA_WITH_CAMELLIA_256_CBC_SHA384    uint16 = 0xC079
-	http2cipher_TLS_RSA_WITH_CAMELLIA_128_GCM_SHA256         uint16 = 0xC07A
-	http2cipher_TLS_RSA_WITH_CAMELLIA_256_GCM_SHA384         uint16 = 0xC07B
-	http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_128_GCM_SHA256     uint16 = 0xC07C
-	http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_256_GCM_SHA384     uint16 = 0xC07D
-	http2cipher_TLS_DH_RSA_WITH_CAMELLIA_128_GCM_SHA256      uint16 = 0xC07E
-	http2cipher_TLS_DH_RSA_WITH_CAMELLIA_256_GCM_SHA384      uint16 = 0xC07F
-	http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_128_GCM_SHA256     uint16 = 0xC080
-	http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_256_GCM_SHA384     uint16 = 0xC081
-	http2cipher_TLS_DH_DSS_WITH_CAMELLIA_128_GCM_SHA256      uint16 = 0xC082
-	http2cipher_TLS_DH_DSS_WITH_CAMELLIA_256_GCM_SHA384      uint16 = 0xC083
-	http2cipher_TLS_DH_anon_WITH_CAMELLIA_128_GCM_SHA256     uint16 = 0xC084
-	http2cipher_TLS_DH_anon_WITH_CAMELLIA_256_GCM_SHA384     uint16 = 0xC085
-	http2cipher_TLS_ECDHE_ECDSA_WITH_CAMELLIA_128_GCM_SHA256 uint16 = 0xC086
-	http2cipher_TLS_ECDHE_ECDSA_WITH_CAMELLIA_256_GCM_SHA384 uint16 = 0xC087
-	http2cipher_TLS_ECDH_ECDSA_WITH_CAMELLIA_128_GCM_SHA256  uint16 = 0xC088
-	http2cipher_TLS_ECDH_ECDSA_WITH_CAMELLIA_256_GCM_SHA384  uint16 = 0xC089
-	http2cipher_TLS_ECDHE_RSA_WITH_CAMELLIA_128_GCM_SHA256   uint16 = 0xC08A
-	http2cipher_TLS_ECDHE_RSA_WITH_CAMELLIA_256_GCM_SHA384   uint16 = 0xC08B
-	http2cipher_TLS_ECDH_RSA_WITH_CAMELLIA_128_GCM_SHA256    uint16 = 0xC08C
-	http2cipher_TLS_ECDH_RSA_WITH_CAMELLIA_256_GCM_SHA384    uint16 = 0xC08D
-	http2cipher_TLS_PSK_WITH_CAMELLIA_128_GCM_SHA256         uint16 = 0xC08E
-	http2cipher_TLS_PSK_WITH_CAMELLIA_256_GCM_SHA384         uint16 = 0xC08F
-	http2cipher_TLS_DHE_PSK_WITH_CAMELLIA_128_GCM_SHA256     uint16 = 0xC090
-	http2cipher_TLS_DHE_PSK_WITH_CAMELLIA_256_GCM_SHA384     uint16 = 0xC091
-	http2cipher_TLS_RSA_PSK_WITH_CAMELLIA_128_GCM_SHA256     uint16 = 0xC092
-	http2cipher_TLS_RSA_PSK_WITH_CAMELLIA_256_GCM_SHA384     uint16 = 0xC093
-	http2cipher_TLS_PSK_WITH_CAMELLIA_128_CBC_SHA256         uint16 = 0xC094
-	http2cipher_TLS_PSK_WITH_CAMELLIA_256_CBC_SHA384         uint16 = 0xC095
-	http2cipher_TLS_DHE_PSK_WITH_CAMELLIA_128_CBC_SHA256     uint16 = 0xC096
-	http2cipher_TLS_DHE_PSK_WITH_CAMELLIA_256_CBC_SHA384     uint16 = 0xC097
-	http2cipher_TLS_RSA_PSK_WITH_CAMELLIA_128_CBC_SHA256     uint16 = 0xC098
-	http2cipher_TLS_RSA_PSK_WITH_CAMELLIA_256_CBC_SHA384     uint16 = 0xC099
-	http2cipher_TLS_ECDHE_PSK_WITH_CAMELLIA_128_CBC_SHA256   uint16 = 0xC09A
-	http2cipher_TLS_ECDHE_PSK_WITH_CAMELLIA_256_CBC_SHA384   uint16 = 0xC09B
-	http2cipher_TLS_RSA_WITH_AES_128_CCM                     uint16 = 0xC09C
-	http2cipher_TLS_RSA_WITH_AES_256_CCM                     uint16 = 0xC09D
-	http2cipher_TLS_DHE_RSA_WITH_AES_128_CCM                 uint16 = 0xC09E
-	http2cipher_TLS_DHE_RSA_WITH_AES_256_CCM                 uint16 = 0xC09F
-	http2cipher_TLS_RSA_WITH_AES_128_CCM_8                   uint16 = 0xC0A0
-	http2cipher_TLS_RSA_WITH_AES_256_CCM_8                   uint16 = 0xC0A1
-	http2cipher_TLS_DHE_RSA_WITH_AES_128_CCM_8               uint16 = 0xC0A2
-	http2cipher_TLS_DHE_RSA_WITH_AES_256_CCM_8               uint16 = 0xC0A3
-	http2cipher_TLS_PSK_WITH_AES_128_CCM                     uint16 = 0xC0A4
-	http2cipher_TLS_PSK_WITH_AES_256_CCM                     uint16 = 0xC0A5
-	http2cipher_TLS_DHE_PSK_WITH_AES_128_CCM                 uint16 = 0xC0A6
-	http2cipher_TLS_DHE_PSK_WITH_AES_256_CCM                 uint16 = 0xC0A7
-	http2cipher_TLS_PSK_WITH_AES_128_CCM_8                   uint16 = 0xC0A8
-	http2cipher_TLS_PSK_WITH_AES_256_CCM_8                   uint16 = 0xC0A9
-	http2cipher_TLS_PSK_DHE_WITH_AES_128_CCM_8               uint16 = 0xC0AA
-	http2cipher_TLS_PSK_DHE_WITH_AES_256_CCM_8               uint16 = 0xC0AB
-	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_128_CCM             uint16 = 0xC0AC
-	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_256_CCM             uint16 = 0xC0AD
-	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_128_CCM_8           uint16 = 0xC0AE
-	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_256_CCM_8           uint16 = 0xC0AF
-	// Unassigned uint16 =  0xC0B0-FF
-	// Unassigned uint16 =  0xC1-CB,*
-	// Unassigned uint16 =  0xCC00-A7
-	http2cipher_TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256   uint16 = 0xCCA8
-	http2cipher_TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 uint16 = 0xCCA9
-	http2cipher_TLS_DHE_RSA_WITH_CHACHA20_POLY1305_SHA256     uint16 = 0xCCAA
-	http2cipher_TLS_PSK_WITH_CHACHA20_POLY1305_SHA256         uint16 = 0xCCAB
-	http2cipher_TLS_ECDHE_PSK_WITH_CHACHA20_POLY1305_SHA256   uint16 = 0xCCAC
-	http2cipher_TLS_DHE_PSK_WITH_CHACHA20_POLY1305_SHA256     uint16 = 0xCCAD
-	http2cipher_TLS_RSA_PSK_WITH_CHACHA20_POLY1305_SHA256     uint16 = 0xCCAE
-)
-
-// isBadCipher reports whether the cipher is blacklisted by the HTTP/2 spec.
-// References:
-// https://tools.ietf.org/html/rfc7540#appendix-A
-// Reject cipher suites from Appendix A.
-// "This list includes those cipher suites that do not
-// offer an ephemeral key exchange and those that are
-// based on the TLS null, stream or block cipher type"
-func http2isBadCipher(cipher uint16) bool {
-	switch cipher {
-	case http2cipher_TLS_NULL_WITH_NULL_NULL,
-		http2cipher_TLS_RSA_WITH_NULL_MD5,
-		http2cipher_TLS_RSA_WITH_NULL_SHA,
-		http2cipher_TLS_RSA_EXPORT_WITH_RC4_40_MD5,
-		http2cipher_TLS_RSA_WITH_RC4_128_MD5,
-		http2cipher_TLS_RSA_WITH_RC4_128_SHA,
-		http2cipher_TLS_RSA_EXPORT_WITH_RC2_CBC_40_MD5,
-		http2cipher_TLS_RSA_WITH_IDEA_CBC_SHA,
-		http2cipher_TLS_RSA_EXPORT_WITH_DES40_CBC_SHA,
-		http2cipher_TLS_RSA_WITH_DES_CBC_SHA,
-		http2cipher_TLS_RSA_WITH_3DES_EDE_CBC_SHA,
-		http2cipher_TLS_DH_DSS_EXPORT_WITH_DES40_CBC_SHA,
-		http2cipher_TLS_DH_DSS_WITH_DES_CBC_SHA,
-		http2cipher_TLS_DH_DSS_WITH_3DES_EDE_CBC_SHA,
-		http2cipher_TLS_DH_RSA_EXPORT_WITH_DES40_CBC_SHA,
-		http2cipher_TLS_DH_RSA_WITH_DES_CBC_SHA,
-		http2cipher_TLS_DH_RSA_WITH_3DES_EDE_CBC_SHA,
-		http2cipher_TLS_DHE_DSS_EXPORT_WITH_DES40_CBC_SHA,
-		http2cipher_TLS_DHE_DSS_WITH_DES_CBC_SHA,
-		http2cipher_TLS_DHE_DSS_WITH_3DES_EDE_CBC_SHA,
-		http2cipher_TLS_DHE_RSA_EXPORT_WITH_DES40_CBC_SHA,
-		http2cipher_TLS_DHE_RSA_WITH_DES_CBC_SHA,
-		http2cipher_TLS_DHE_RSA_WITH_3DES_EDE_CBC_SHA,
-		http2cipher_TLS_DH_anon_EXPORT_WITH_RC4_40_MD5,
-		http2cipher_TLS_DH_anon_WITH_RC4_128_MD5,
-		http2cipher_TLS_DH_anon_EXPORT_WITH_DES40_CBC_SHA,
-		http2cipher_TLS_DH_anon_WITH_DES_CBC_SHA,
-		http2cipher_TLS_DH_anon_WITH_3DES_EDE_CBC_SHA,
-		http2cipher_TLS_KRB5_WITH_DES_CBC_SHA,
-		http2cipher_TLS_KRB5_WITH_3DES_EDE_CBC_SHA,
-		http2cipher_TLS_KRB5_WITH_RC4_128_SHA,
-		http2cipher_TLS_KRB5_WITH_IDEA_CBC_SHA,
-		http2cipher_TLS_KRB5_WITH_DES_CBC_MD5,
-		http2cipher_TLS_KRB5_WITH_3DES_EDE_CBC_MD5,
-		http2cipher_TLS_KRB5_WITH_RC4_128_MD5,
-		http2cipher_TLS_KRB5_WITH_IDEA_CBC_MD5,
-		http2cipher_TLS_KRB5_EXPORT_WITH_DES_CBC_40_SHA,
-		http2cipher_TLS_KRB5_EXPORT_WITH_RC2_CBC_40_SHA,
-		http2cipher_TLS_KRB5_EXPORT_WITH_RC4_40_SHA,
-		http2cipher_TLS_KRB5_EXPORT_WITH_DES_CBC_40_MD5,
-		http2cipher_TLS_KRB5_EXPORT_WITH_RC2_CBC_40_MD5,
-		http2cipher_TLS_KRB5_EXPORT_WITH_RC4_40_MD5,
-		http2cipher_TLS_PSK_WITH_NULL_SHA,
-		http2cipher_TLS_DHE_PSK_WITH_NULL_SHA,
-		http2cipher_TLS_RSA_PSK_WITH_NULL_SHA,
-		http2cipher_TLS_RSA_WITH_AES_128_CBC_SHA,
-		http2cipher_TLS_DH_DSS_WITH_AES_128_CBC_SHA,
-		http2cipher_TLS_DH_RSA_WITH_AES_128_CBC_SHA,
-		http2cipher_TLS_DHE_DSS_WITH_AES_128_CBC_SHA,
-		http2cipher_TLS_DHE_RSA_WITH_AES_128_CBC_SHA,
-		http2cipher_TLS_DH_anon_WITH_AES_128_CBC_SHA,
-		http2cipher_TLS_RSA_WITH_AES_256_CBC_SHA,
-		http2cipher_TLS_DH_DSS_WITH_AES_256_CBC_SHA,
-		http2cipher_TLS_DH_RSA_WITH_AES_256_CBC_SHA,
-		http2cipher_TLS_DHE_DSS_WITH_AES_256_CBC_SHA,
-		http2cipher_TLS_DHE_RSA_WITH_AES_256_CBC_SHA,
-		http2cipher_TLS_DH_anon_WITH_AES_256_CBC_SHA,
-		http2cipher_TLS_RSA_WITH_NULL_SHA256,
-		http2cipher_TLS_RSA_WITH_AES_128_CBC_SHA256,
-		http2cipher_TLS_RSA_WITH_AES_256_CBC_SHA256,
-		http2cipher_TLS_DH_DSS_WITH_AES_128_CBC_SHA256,
-		http2cipher_TLS_DH_RSA_WITH_AES_128_CBC_SHA256,
-		http2cipher_TLS_DHE_DSS_WITH_AES_128_CBC_SHA256,
-		http2cipher_TLS_RSA_WITH_CAMELLIA_128_CBC_SHA,
-		http2cipher_TLS_DH_DSS_WITH_CAMELLIA_128_CBC_SHA,
-		http2cipher_TLS_DH_RSA_WITH_CAMELLIA_128_CBC_SHA,
-		http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_128_CBC_SHA,
-		http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_128_CBC_SHA,
-		http2cipher_TLS_DH_anon_WITH_CAMELLIA_128_CBC_SHA,
-		http2cipher_TLS_DHE_RSA_WITH_AES_128_CBC_SHA256,
-		http2cipher_TLS_DH_DSS_WITH_AES_256_CBC_SHA256,
-		http2cipher_TLS_DH_RSA_WITH_AES_256_CBC_SHA256,
-		http2cipher_TLS_DHE_DSS_WITH_AES_256_CBC_SHA256,
-		http2cipher_TLS_DHE_RSA_WITH_AES_256_CBC_SHA256,
-		http2cipher_TLS_DH_anon_WITH_AES_128_CBC_SHA256,
-		http2cipher_TLS_DH_anon_WITH_AES_256_CBC_SHA256,
-		http2cipher_TLS_RSA_WITH_CAMELLIA_256_CBC_SHA,
-		http2cipher_TLS_DH_DSS_WITH_CAMELLIA_256_CBC_SHA,
-		http2cipher_TLS_DH_RSA_WITH_CAMELLIA_256_CBC_SHA,
-		http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_256_CBC_SHA,
-		http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_256_CBC_SHA,
-		http2cipher_TLS_DH_anon_WITH_CAMELLIA_256_CBC_SHA,
-		http2cipher_TLS_PSK_WITH_RC4_128_SHA,
-		http2cipher_TLS_PSK_WITH_3DES_EDE_CBC_SHA,
-		http2cipher_TLS_PSK_WITH_AES_128_CBC_SHA,
-		http2cipher_TLS_PSK_WITH_AES_256_CBC_SHA,
-		http2cipher_TLS_DHE_PSK_WITH_RC4_128_SHA,
-		http2cipher_TLS_DHE_PSK_WITH_3DES_EDE_CBC_SHA,
-		http2cipher_TLS_DHE_PSK_WITH_AES_128_CBC_SHA,
-		http2cipher_TLS_DHE_PSK_WITH_AES_256_CBC_SHA,
-		http2cipher_TLS_RSA_PSK_WITH_RC4_128_SHA,
-		http2cipher_TLS_RSA_PSK_WITH_3DES_EDE_CBC_SHA,
-		http2cipher_TLS_RSA_PSK_WITH_AES_128_CBC_SHA,
-		http2cipher_TLS_RSA_PSK_WITH_AES_256_CBC_SHA,
-		http2cipher_TLS_RSA_WITH_SEED_CBC_SHA,
-		http2cipher_TLS_DH_DSS_WITH_SEED_CBC_SHA,
-		http2cipher_TLS_DH_RSA_WITH_SEED_CBC_SHA,
-		http2cipher_TLS_DHE_DSS_WITH_SEED_CBC_SHA,
-		http2cipher_TLS_DHE_RSA_WITH_SEED_CBC_SHA,
-		http2cipher_TLS_DH_anon_WITH_SEED_CBC_SHA,
-		http2cipher_TLS_RSA_WITH_AES_128_GCM_SHA256,
-		http2cipher_TLS_RSA_WITH_AES_256_GCM_SHA384,
-		http2cipher_TLS_DH_RSA_WITH_AES_128_GCM_SHA256,
-		http2cipher_TLS_DH_RSA_WITH_AES_256_GCM_SHA384,
-		http2cipher_TLS_DH_DSS_WITH_AES_128_GCM_SHA256,
-		http2cipher_TLS_DH_DSS_WITH_AES_256_GCM_SHA384,
-		http2cipher_TLS_DH_anon_WITH_AES_128_GCM_SHA256,
-		http2cipher_TLS_DH_anon_WITH_AES_256_GCM_SHA384,
-		http2cipher_TLS_PSK_WITH_AES_128_GCM_SHA256,
-		http2cipher_TLS_PSK_WITH_AES_256_GCM_SHA384,
-		http2cipher_TLS_RSA_PSK_WITH_AES_128_GCM_SHA256,
-		http2cipher_TLS_RSA_PSK_WITH_AES_256_GCM_SHA384,
-		http2cipher_TLS_PSK_WITH_AES_128_CBC_SHA256,
-		http2cipher_TLS_PSK_WITH_AES_256_CBC_SHA384,
-		http2cipher_TLS_PSK_WITH_NULL_SHA256,
-		http2cipher_TLS_PSK_WITH_NULL_SHA384,
-		http2cipher_TLS_DHE_PSK_WITH_AES_128_CBC_SHA256,
-		http2cipher_TLS_DHE_PSK_WITH_AES_256_CBC_SHA384,
-		http2cipher_TLS_DHE_PSK_WITH_NULL_SHA256,
-		http2cipher_TLS_DHE_PSK_WITH_NULL_SHA384,
-		http2cipher_TLS_RSA_PSK_WITH_AES_128_CBC_SHA256,
-		http2cipher_TLS_RSA_PSK_WITH_AES_256_CBC_SHA384,
-		http2cipher_TLS_RSA_PSK_WITH_NULL_SHA256,
-		http2cipher_TLS_RSA_PSK_WITH_NULL_SHA384,
-		http2cipher_TLS_RSA_WITH_CAMELLIA_128_CBC_SHA256,
-		http2cipher_TLS_DH_DSS_WITH_CAMELLIA_128_CBC_SHA256,
-		http2cipher_TLS_DH_RSA_WITH_CAMELLIA_128_CBC_SHA256,
-		http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_128_CBC_SHA256,
-		http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_128_CBC_SHA256,
-		http2cipher_TLS_DH_anon_WITH_CAMELLIA_128_CBC_SHA256,
-		http2cipher_TLS_RSA_WITH_CAMELLIA_256_CBC_SHA256,
-		http2cipher_TLS_DH_DSS_WITH_CAMELLIA_256_CBC_SHA256,
-		http2cipher_TLS_DH_RSA_WITH_CAMELLIA_256_CBC_SHA256,
-		http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_256_CBC_SHA256,
-		http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_256_CBC_SHA256,
-		http2cipher_TLS_DH_anon_WITH_CAMELLIA_256_CBC_SHA256,
-		http2cipher_TLS_EMPTY_RENEGOTIATION_INFO_SCSV,
-		http2cipher_TLS_ECDH_ECDSA_WITH_NULL_SHA,
-		http2cipher_TLS_ECDH_ECDSA_WITH_RC4_128_SHA,
-		http2cipher_TLS_ECDH_ECDSA_WITH_3DES_EDE_CBC_SHA,
-		http2cipher_TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA,
-		http2cipher_TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA,
-		http2cipher_TLS_ECDHE_ECDSA_WITH_NULL_SHA,
-		http2cipher_TLS_ECDHE_ECDSA_WITH_RC4_128_SHA,
-		http2cipher_TLS_ECDHE_ECDSA_WITH_3DES_EDE_CBC_SHA,
-		http2cipher_TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
-		http2cipher_TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA,
-		http2cipher_TLS_ECDH_RSA_WITH_NULL_SHA,
-		http2cipher_TLS_ECDH_RSA_WITH_RC4_128_SHA,
-		http2cipher_TLS_ECDH_RSA_WITH_3DES_EDE_CBC_SHA,
-		http2cipher_TLS_ECDH_RSA_WITH_AES_128_CBC_SHA,
-		http2cipher_TLS_ECDH_RSA_WITH_AES_256_CBC_SHA,
-		http2cipher_TLS_ECDHE_RSA_WITH_NULL_SHA,
-		http2cipher_TLS_ECDHE_RSA_WITH_RC4_128_SHA,
-		http2cipher_TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA,
-		http2cipher_TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
-		http2cipher_TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
-		http2cipher_TLS_ECDH_anon_WITH_NULL_SHA,
-		http2cipher_TLS_ECDH_anon_WITH_RC4_128_SHA,
-		http2cipher_TLS_ECDH_anon_WITH_3DES_EDE_CBC_SHA,
-		http2cipher_TLS_ECDH_anon_WITH_AES_128_CBC_SHA,
-		http2cipher_TLS_ECDH_anon_WITH_AES_256_CBC_SHA,
-		http2cipher_TLS_SRP_SHA_WITH_3DES_EDE_CBC_SHA,
-		http2cipher_TLS_SRP_SHA_RSA_WITH_3DES_EDE_CBC_SHA,
-		http2cipher_TLS_SRP_SHA_DSS_WITH_3DES_EDE_CBC_SHA,
-		http2cipher_TLS_SRP_SHA_WITH_AES_128_CBC_SHA,
-		http2cipher_TLS_SRP_SHA_RSA_WITH_AES_128_CBC_SHA,
-		http2cipher_TLS_SRP_SHA_DSS_WITH_AES_128_CBC_SHA,
-		http2cipher_TLS_SRP_SHA_WITH_AES_256_CBC_SHA,
-		http2cipher_TLS_SRP_SHA_RSA_WITH_AES_256_CBC_SHA,
-		http2cipher_TLS_SRP_SHA_DSS_WITH_AES_256_CBC_SHA,
-		http2cipher_TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256,
-		http2cipher_TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384,
-		http2cipher_TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA256,
-		http2cipher_TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA384,
-		http2cipher_TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256,
-		http2cipher_TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384,
-		http2cipher_TLS_ECDH_RSA_WITH_AES_128_CBC_SHA256,
-		http2cipher_TLS_ECDH_RSA_WITH_AES_256_CBC_SHA384,
-		http2cipher_TLS_ECDH_ECDSA_WITH_AES_128_GCM_SHA256,
-		http2cipher_TLS_ECDH_ECDSA_WITH_AES_256_GCM_SHA384,
-		http2cipher_TLS_ECDH_RSA_WITH_AES_128_GCM_SHA256,
-		http2cipher_TLS_ECDH_RSA_WITH_AES_256_GCM_SHA384,
-		http2cipher_TLS_ECDHE_PSK_WITH_RC4_128_SHA,
-		http2cipher_TLS_ECDHE_PSK_WITH_3DES_EDE_CBC_SHA,
-		http2cipher_TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA,
-		http2cipher_TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA,
-		http2cipher_TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA256,
-		http2cipher_TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA384,
-		http2cipher_TLS_ECDHE_PSK_WITH_NULL_SHA,
-		http2cipher_TLS_ECDHE_PSK_WITH_NULL_SHA256,
-		http2cipher_TLS_ECDHE_PSK_WITH_NULL_SHA384,
-		http2cipher_TLS_RSA_WITH_ARIA_128_CBC_SHA256,
-		http2cipher_TLS_RSA_WITH_ARIA_256_CBC_SHA384,
-		http2cipher_TLS_DH_DSS_WITH_ARIA_128_CBC_SHA256,
-		http2cipher_TLS_DH_DSS_WITH_ARIA_256_CBC_SHA384,
-		http2cipher_TLS_DH_RSA_WITH_ARIA_128_CBC_SHA256,
-		http2cipher_TLS_DH_RSA_WITH_ARIA_256_CBC_SHA384,
-		http2cipher_TLS_DHE_DSS_WITH_ARIA_128_CBC_SHA256,
-		http2cipher_TLS_DHE_DSS_WITH_ARIA_256_CBC_SHA384,
-		http2cipher_TLS_DHE_RSA_WITH_ARIA_128_CBC_SHA256,
-		http2cipher_TLS_DHE_RSA_WITH_ARIA_256_CBC_SHA384,
-		http2cipher_TLS_DH_anon_WITH_ARIA_128_CBC_SHA256,
-		http2cipher_TLS_DH_anon_WITH_ARIA_256_CBC_SHA384,
-		http2cipher_TLS_ECDHE_ECDSA_WITH_ARIA_128_CBC_SHA256,
-		http2cipher_TLS_ECDHE_ECDSA_WITH_ARIA_256_CBC_SHA384,
-		http2cipher_TLS_ECDH_ECDSA_WITH_ARIA_128_CBC_SHA256,
-		http2cipher_TLS_ECDH_ECDSA_WITH_ARIA_256_CBC_SHA384,
-		http2cipher_TLS_ECDHE_RSA_WITH_ARIA_128_CBC_SHA256,
-		http2cipher_TLS_ECDHE_RSA_WITH_ARIA_256_CBC_SHA384,
-		http2cipher_TLS_ECDH_RSA_WITH_ARIA_128_CBC_SHA256,
-		http2cipher_TLS_ECDH_RSA_WITH_ARIA_256_CBC_SHA384,
-		http2cipher_TLS_RSA_WITH_ARIA_128_GCM_SHA256,
-		http2cipher_TLS_RSA_WITH_ARIA_256_GCM_SHA384,
-		http2cipher_TLS_DH_RSA_WITH_ARIA_128_GCM_SHA256,
-		http2cipher_TLS_DH_RSA_WITH_ARIA_256_GCM_SHA384,
-		http2cipher_TLS_DH_DSS_WITH_ARIA_128_GCM_SHA256,
-		http2cipher_TLS_DH_DSS_WITH_ARIA_256_GCM_SHA384,
-		http2cipher_TLS_DH_anon_WITH_ARIA_128_GCM_SHA256,
-		http2cipher_TLS_DH_anon_WITH_ARIA_256_GCM_SHA384,
-		http2cipher_TLS_ECDH_ECDSA_WITH_ARIA_128_GCM_SHA256,
-		http2cipher_TLS_ECDH_ECDSA_WITH_ARIA_256_GCM_SHA384,
-		http2cipher_TLS_ECDH_RSA_WITH_ARIA_128_GCM_SHA256,
-		http2cipher_TLS_ECDH_RSA_WITH_ARIA_256_GCM_SHA384,
-		http2cipher_TLS_PSK_WITH_ARIA_128_CBC_SHA256,
-		http2cipher_TLS_PSK_WITH_ARIA_256_CBC_SHA384,
-		http2cipher_TLS_DHE_PSK_WITH_ARIA_128_CBC_SHA256,
-		http2cipher_TLS_DHE_PSK_WITH_ARIA_256_CBC_SHA384,
-		http2cipher_TLS_RSA_PSK_WITH_ARIA_128_CBC_SHA256,
-		http2cipher_TLS_RSA_PSK_WITH_ARIA_256_CBC_SHA384,
-		http2cipher_TLS_PSK_WITH_ARIA_128_GCM_SHA256,
-		http2cipher_TLS_PSK_WITH_ARIA_256_GCM_SHA384,
-		http2cipher_TLS_RSA_PSK_WITH_ARIA_128_GCM_SHA256,
-		http2cipher_TLS_RSA_PSK_WITH_ARIA_256_GCM_SHA384,
-		http2cipher_TLS_ECDHE_PSK_WITH_ARIA_128_CBC_SHA256,
-		http2cipher_TLS_ECDHE_PSK_WITH_ARIA_256_CBC_SHA384,
-		http2cipher_TLS_ECDHE_ECDSA_WITH_CAMELLIA_128_CBC_SHA256,
-		http2cipher_TLS_ECDHE_ECDSA_WITH_CAMELLIA_256_CBC_SHA384,
-		http2cipher_TLS_ECDH_ECDSA_WITH_CAMELLIA_128_CBC_SHA256,
-		http2cipher_TLS_ECDH_ECDSA_WITH_CAMELLIA_256_CBC_SHA384,
-		http2cipher_TLS_ECDHE_RSA_WITH_CAMELLIA_128_CBC_SHA256,
-		http2cipher_TLS_ECDHE_RSA_WITH_CAMELLIA_256_CBC_SHA384,
-		http2cipher_TLS_ECDH_RSA_WITH_CAMELLIA_128_CBC_SHA256,
-		http2cipher_TLS_ECDH_RSA_WITH_CAMELLIA_256_CBC_SHA384,
-		http2cipher_TLS_RSA_WITH_CAMELLIA_128_GCM_SHA256,
-		http2cipher_TLS_RSA_WITH_CAMELLIA_256_GCM_SHA384,
-		http2cipher_TLS_DH_RSA_WITH_CAMELLIA_128_GCM_SHA256,
-		http2cipher_TLS_DH_RSA_WITH_CAMELLIA_256_GCM_SHA384,
-		http2cipher_TLS_DH_DSS_WITH_CAMELLIA_128_GCM_SHA256,
-		http2cipher_TLS_DH_DSS_WITH_CAMELLIA_256_GCM_SHA384,
-		http2cipher_TLS_DH_anon_WITH_CAMELLIA_128_GCM_SHA256,
-		http2cipher_TLS_DH_anon_WITH_CAMELLIA_256_GCM_SHA384,
-		http2cipher_TLS_ECDH_ECDSA_WITH_CAMELLIA_128_GCM_SHA256,
-		http2cipher_TLS_ECDH_ECDSA_WITH_CAMELLIA_256_GCM_SHA384,
-		http2cipher_TLS_ECDH_RSA_WITH_CAMELLIA_128_GCM_SHA256,
-		http2cipher_TLS_ECDH_RSA_WITH_CAMELLIA_256_GCM_SHA384,
-		http2cipher_TLS_PSK_WITH_CAMELLIA_128_GCM_SHA256,
-		http2cipher_TLS_PSK_WITH_CAMELLIA_256_GCM_SHA384,
-		http2cipher_TLS_RSA_PSK_WITH_CAMELLIA_128_GCM_SHA256,
-		http2cipher_TLS_RSA_PSK_WITH_CAMELLIA_256_GCM_SHA384,
-		http2cipher_TLS_PSK_WITH_CAMELLIA_128_CBC_SHA256,
-		http2cipher_TLS_PSK_WITH_CAMELLIA_256_CBC_SHA384,
-		http2cipher_TLS_DHE_PSK_WITH_CAMELLIA_128_CBC_SHA256,
-		http2cipher_TLS_DHE_PSK_WITH_CAMELLIA_256_CBC_SHA384,
-		http2cipher_TLS_RSA_PSK_WITH_CAMELLIA_128_CBC_SHA256,
-		http2cipher_TLS_RSA_PSK_WITH_CAMELLIA_256_CBC_SHA384,
-		http2cipher_TLS_ECDHE_PSK_WITH_CAMELLIA_128_CBC_SHA256,
-		http2cipher_TLS_ECDHE_PSK_WITH_CAMELLIA_256_CBC_SHA384,
-		http2cipher_TLS_RSA_WITH_AES_128_CCM,
-		http2cipher_TLS_RSA_WITH_AES_256_CCM,
-		http2cipher_TLS_RSA_WITH_AES_128_CCM_8,
-		http2cipher_TLS_RSA_WITH_AES_256_CCM_8,
-		http2cipher_TLS_PSK_WITH_AES_128_CCM,
-		http2cipher_TLS_PSK_WITH_AES_256_CCM,
-		http2cipher_TLS_PSK_WITH_AES_128_CCM_8,
-		http2cipher_TLS_PSK_WITH_AES_256_CCM_8:
-		return true
-	default:
-		return false
-	}
-}
-
-// ClientConnPool manages a pool of HTTP/2 client connections.
-type http2ClientConnPool interface {
-	// GetClientConn returns a specific HTTP/2 connection (usually
-	// a TLS-TCP connection) to an HTTP/2 server. On success, the
-	// returned ClientConn accounts for the upcoming RoundTrip
-	// call, so the caller should not omit it. If the caller needs
-	// to, ClientConn.RoundTrip can be called with a bogus
-	// new(http.Request) to release the stream reservation.
-	GetClientConn(req *Request, addr string) (*http2ClientConn, error)
-	MarkDead(*http2ClientConn)
-}
-
-// clientConnPoolIdleCloser is the interface implemented by ClientConnPool
-// implementations which can close their idle connections.
-type http2clientConnPoolIdleCloser interface {
-	http2ClientConnPool
-	closeIdleConnections()
-}
-
-var (
-	_ http2clientConnPoolIdleCloser = (*http2clientConnPool)(nil)
-	_ http2clientConnPoolIdleCloser = http2noDialClientConnPool{}
-)
-
-// TODO: use singleflight for dialing and addConnCalls?
-type http2clientConnPool struct {
-	t *http2Transport
-
-	mu sync.Mutex // TODO: maybe switch to RWMutex
-	// TODO: add support for sharing conns based on cert names
-	// (e.g. share conn for googleapis.com and appspot.com)
-	conns        map[string][]*http2ClientConn // key is host:port
-	dialing      map[string]*http2dialCall     // currently in-flight dials
-	keys         map[*http2ClientConn][]string
-	addConnCalls map[string]*http2addConnCall // in-flight addConnIfNeeded calls
-}
-
-func (p *http2clientConnPool) GetClientConn(req *Request, addr string) (*http2ClientConn, error) {
-	return p.getClientConn(req, addr, http2dialOnMiss)
-}
-
-const (
-	http2dialOnMiss   = true
-	http2noDialOnMiss = false
-)
-
-func (p *http2clientConnPool) getClientConn(req *Request, addr string, dialOnMiss bool) (*http2ClientConn, error) {
-	// TODO(dneil): Dial a new connection when t.DisableKeepAlives is set?
-	if http2isConnectionCloseRequest(req) && dialOnMiss {
-		// It gets its own connection.
-		http2traceGetConn(req, addr)
-		const singleUse = true
-		cc, err := p.t.dialClientConn(req.Context(), addr, singleUse)
-		if err != nil {
-			return nil, err
-		}
-		return cc, nil
-	}
-	for {
-		p.mu.Lock()
-		for _, cc := range p.conns[addr] {
-			if cc.ReserveNewRequest() {
-				// When a connection is presented to us by the net/http package,
-				// the GetConn hook has already been called.
-				// Don't call it a second time here.
-				if !cc.getConnCalled {
-					http2traceGetConn(req, addr)
-				}
-				cc.getConnCalled = false
-				p.mu.Unlock()
-				return cc, nil
-			}
-		}
-		if !dialOnMiss {
-			p.mu.Unlock()
-			return nil, http2ErrNoCachedConn
-		}
-		http2traceGetConn(req, addr)
-		call := p.getStartDialLocked(req.Context(), addr)
-		p.mu.Unlock()
-		<-call.done
-		if http2shouldRetryDial(call, req) {
-			continue
-		}
-		cc, err := call.res, call.err
-		if err != nil {
-			return nil, err
-		}
-		if cc.ReserveNewRequest() {
-			return cc, nil
-		}
-	}
-}
-
-// dialCall is an in-flight Transport dial call to a host.
-type http2dialCall struct {
-	_ http2incomparable
-	p *http2clientConnPool
-	// the context associated with the request
-	// that created this dialCall
-	ctx  context.Context
-	done chan struct{}    // closed when done
-	res  *http2ClientConn // valid after done is closed
-	err  error            // valid after done is closed
-}
-
-// requires p.mu is held.
-func (p *http2clientConnPool) getStartDialLocked(ctx context.Context, addr string) *http2dialCall {
-	if call, ok := p.dialing[addr]; ok {
-		// A dial is already in-flight. Don't start another.
-		return call
-	}
-	call := &http2dialCall{p: p, done: make(chan struct{}), ctx: ctx}
-	if p.dialing == nil {
-		p.dialing = make(map[string]*http2dialCall)
-	}
-	p.dialing[addr] = call
-	go call.dial(call.ctx, addr)
-	return call
-}
-
-// run in its own goroutine.
-func (c *http2dialCall) dial(ctx context.Context, addr string) {
-	const singleUse = false // shared conn
-	c.res, c.err = c.p.t.dialClientConn(ctx, addr, singleUse)
-	close(c.done)
-
-	c.p.mu.Lock()
-	delete(c.p.dialing, addr)
-	if c.err == nil {
-		c.p.addConnLocked(addr, c.res)
-	}
-	c.p.mu.Unlock()
-}
-
-// addConnIfNeeded makes a NewClientConn out of c if a connection for key doesn't
-// already exist. It coalesces concurrent calls with the same key.
-// This is used by the http1 Transport code when it creates a new connection. Because
-// the http1 Transport doesn't de-dup TCP dials to outbound hosts (because it doesn't know
-// the protocol), it can get into a situation where it has multiple TLS connections.
-// This code decides which ones live or die.
-// The return value used is whether c was used.
-// c is never closed.
-func (p *http2clientConnPool) addConnIfNeeded(key string, t *http2Transport, c *tls.Conn) (used bool, err error) {
-	p.mu.Lock()
-	for _, cc := range p.conns[key] {
-		if cc.CanTakeNewRequest() {
-			p.mu.Unlock()
-			return false, nil
-		}
-	}
-	call, dup := p.addConnCalls[key]
-	if !dup {
-		if p.addConnCalls == nil {
-			p.addConnCalls = make(map[string]*http2addConnCall)
-		}
-		call = &http2addConnCall{
-			p:    p,
-			done: make(chan struct{}),
-		}
-		p.addConnCalls[key] = call
-		go call.run(t, key, c)
-	}
-	p.mu.Unlock()
-
-	<-call.done
-	if call.err != nil {
-		return false, call.err
-	}
-	return !dup, nil
-}
-
-type http2addConnCall struct {
-	_    http2incomparable
-	p    *http2clientConnPool
-	done chan struct{} // closed when done
-	err  error
-}
-
-func (c *http2addConnCall) run(t *http2Transport, key string, tc *tls.Conn) {
-	cc, err := t.NewClientConn(tc)
-
-	p := c.p
-	p.mu.Lock()
-	if err != nil {
-		c.err = err
-	} else {
-		cc.getConnCalled = true // already called by the net/http package
-		p.addConnLocked(key, cc)
-	}
-	delete(p.addConnCalls, key)
-	p.mu.Unlock()
-	close(c.done)
-}
-
-// p.mu must be held
-func (p *http2clientConnPool) addConnLocked(key string, cc *http2ClientConn) {
-	for _, v := range p.conns[key] {
-		if v == cc {
-			return
-		}
-	}
-	if p.conns == nil {
-		p.conns = make(map[string][]*http2ClientConn)
-	}
-	if p.keys == nil {
-		p.keys = make(map[*http2ClientConn][]string)
-	}
-	p.conns[key] = append(p.conns[key], cc)
-	p.keys[cc] = append(p.keys[cc], key)
-}
-
-func (p *http2clientConnPool) MarkDead(cc *http2ClientConn) {
-	p.mu.Lock()
-	defer p.mu.Unlock()
-	for _, key := range p.keys[cc] {
-		vv, ok := p.conns[key]
-		if !ok {
-			continue
-		}
-		newList := http2filterOutClientConn(vv, cc)
-		if len(newList) > 0 {
-			p.conns[key] = newList
-		} else {
-			delete(p.conns, key)
-		}
-	}
-	delete(p.keys, cc)
-}
-
-func (p *http2clientConnPool) closeIdleConnections() {
-	p.mu.Lock()
-	defer p.mu.Unlock()
-	// TODO: don't close a cc if it was just added to the pool
-	// milliseconds ago and has never been used. There's currently
-	// a small race window with the HTTP/1 Transport's integration
-	// where it can add an idle conn just before using it, and
-	// somebody else can concurrently call CloseIdleConns and
-	// break some caller's RoundTrip.
-	for _, vv := range p.conns {
-		for _, cc := range vv {
-			cc.closeIfIdle()
-		}
-	}
-}
-
-func http2filterOutClientConn(in []*http2ClientConn, exclude *http2ClientConn) []*http2ClientConn {
-	out := in[:0]
-	for _, v := range in {
-		if v != exclude {
-			out = append(out, v)
-		}
-	}
-	// If we filtered it out, zero out the last item to prevent
-	// the GC from seeing it.
-	if len(in) != len(out) {
-		in[len(in)-1] = nil
-	}
-	return out
-}
-
-// noDialClientConnPool is an implementation of http2.ClientConnPool
-// which never dials. We let the HTTP/1.1 client dial and use its TLS
-// connection instead.
-type http2noDialClientConnPool struct{ *http2clientConnPool }
-
-func (p http2noDialClientConnPool) GetClientConn(req *Request, addr string) (*http2ClientConn, error) {
-	return p.getClientConn(req, addr, http2noDialOnMiss)
-}
-
-// shouldRetryDial reports whether the current request should
-// retry dialing after the call finished unsuccessfully, for example
-// if the dial was canceled because of a context cancellation or
-// deadline expiry.
-func http2shouldRetryDial(call *http2dialCall, req *Request) bool {
-	if call.err == nil {
-		// No error, no need to retry
-		return false
-	}
-	if call.ctx == req.Context() {
-		// If the call has the same context as the request, the dial
-		// should not be retried, since any cancellation will have come
-		// from this request.
-		return false
-	}
-	if !errors.Is(call.err, context.Canceled) && !errors.Is(call.err, context.DeadlineExceeded) {
-		// If the call error is not because of a context cancellation or a deadline expiry,
-		// the dial should not be retried.
-		return false
-	}
-	// Only retry if the error is a context cancellation error or deadline expiry
-	// and the context associated with the call was canceled or expired.
-	return call.ctx.Err() != nil
-}
-
-// Buffer chunks are allocated from a pool to reduce pressure on GC.
-// The maximum wasted space per dataBuffer is 2x the largest size class,
-// which happens when the dataBuffer has multiple chunks and there is
-// one unread byte in both the first and last chunks. We use a few size
-// classes to minimize overheads for servers that typically receive very
-// small request bodies.
-//
-// TODO: Benchmark to determine if the pools are necessary. The GC may have
-// improved enough that we can instead allocate chunks like this:
-// make([]byte, max(16<<10, expectedBytesRemaining))
-var (
-	http2dataChunkSizeClasses = []int{
-		1 << 10,
-		2 << 10,
-		4 << 10,
-		8 << 10,
-		16 << 10,
-	}
-	http2dataChunkPools = [...]sync.Pool{
-		{New: func() interface{} { return make([]byte, 1<<10) }},
-		{New: func() interface{} { return make([]byte, 2<<10) }},
-		{New: func() interface{} { return make([]byte, 4<<10) }},
-		{New: func() interface{} { return make([]byte, 8<<10) }},
-		{New: func() interface{} { return make([]byte, 16<<10) }},
-	}
-)
-
-func http2getDataBufferChunk(size int64) []byte {
-	i := 0
-	for ; i < len(http2dataChunkSizeClasses)-1; i++ {
-		if size <= int64(http2dataChunkSizeClasses[i]) {
-			break
-		}
-	}
-	return http2dataChunkPools[i].Get().([]byte)
-}
-
-func http2putDataBufferChunk(p []byte) {
-	for i, n := range http2dataChunkSizeClasses {
-		if len(p) == n {
-			http2dataChunkPools[i].Put(p)
-			return
-		}
-	}
-	panic(fmt.Sprintf("unexpected buffer len=%v", len(p)))
-}
-
-// dataBuffer is an io.ReadWriter backed by a list of data chunks.
-// Each dataBuffer is used to read DATA frames on a single stream.
-// The buffer is divided into chunks so the server can limit the
-// total memory used by a single connection without limiting the
-// request body size on any single stream.
-type http2dataBuffer struct {
-	chunks   [][]byte
-	r        int   // next byte to read is chunks[0][r]
-	w        int   // next byte to write is chunks[len(chunks)-1][w]
-	size     int   // total buffered bytes
-	expected int64 // we expect at least this many bytes in future Write calls (ignored if <= 0)
-}
-
-var http2errReadEmpty = errors.New("read from empty dataBuffer")
-
-// Read copies bytes from the buffer into p.
-// It is an error to read when no data is available.
-func (b *http2dataBuffer) Read(p []byte) (int, error) {
-	if b.size == 0 {
-		return 0, http2errReadEmpty
-	}
-	var ntotal int
-	for len(p) > 0 && b.size > 0 {
-		readFrom := b.bytesFromFirstChunk()
-		n := copy(p, readFrom)
-		p = p[n:]
-		ntotal += n
-		b.r += n
-		b.size -= n
-		// If the first chunk has been consumed, advance to the next chunk.
-		if b.r == len(b.chunks[0]) {
-			http2putDataBufferChunk(b.chunks[0])
-			end := len(b.chunks) - 1
-			copy(b.chunks[:end], b.chunks[1:])
-			b.chunks[end] = nil
-			b.chunks = b.chunks[:end]
-			b.r = 0
-		}
-	}
-	return ntotal, nil
-}
-
-func (b *http2dataBuffer) bytesFromFirstChunk() []byte {
-	if len(b.chunks) == 1 {
-		return b.chunks[0][b.r:b.w]
-	}
-	return b.chunks[0][b.r:]
-}
-
-// Len returns the number of bytes of the unread portion of the buffer.
-func (b *http2dataBuffer) Len() int {
-	return b.size
-}
-
-// Write appends p to the buffer.
-func (b *http2dataBuffer) Write(p []byte) (int, error) {
-	ntotal := len(p)
-	for len(p) > 0 {
-		// If the last chunk is empty, allocate a new chunk. Try to allocate
-		// enough to fully copy p plus any additional bytes we expect to
-		// receive. However, this may allocate less than len(p).
-		want := int64(len(p))
-		if b.expected > want {
-			want = b.expected
-		}
-		chunk := b.lastChunkOrAlloc(want)
-		n := copy(chunk[b.w:], p)
-		p = p[n:]
-		b.w += n
-		b.size += n
-		b.expected -= int64(n)
-	}
-	return ntotal, nil
-}
-
-func (b *http2dataBuffer) lastChunkOrAlloc(want int64) []byte {
-	if len(b.chunks) != 0 {
-		last := b.chunks[len(b.chunks)-1]
-		if b.w < len(last) {
-			return last
-		}
-	}
-	chunk := http2getDataBufferChunk(want)
-	b.chunks = append(b.chunks, chunk)
-	b.w = 0
-	return chunk
-}
-
-// An ErrCode is an unsigned 32-bit error code as defined in the HTTP/2 spec.
-type http2ErrCode uint32
-
-const (
-	http2ErrCodeNo                 http2ErrCode = 0x0
-	http2ErrCodeProtocol           http2ErrCode = 0x1
-	http2ErrCodeInternal           http2ErrCode = 0x2
-	http2ErrCodeFlowControl        http2ErrCode = 0x3
-	http2ErrCodeSettingsTimeout    http2ErrCode = 0x4
-	http2ErrCodeStreamClosed       http2ErrCode = 0x5
-	http2ErrCodeFrameSize          http2ErrCode = 0x6
-	http2ErrCodeRefusedStream      http2ErrCode = 0x7
-	http2ErrCodeCancel             http2ErrCode = 0x8
-	http2ErrCodeCompression        http2ErrCode = 0x9
-	http2ErrCodeConnect            http2ErrCode = 0xa
-	http2ErrCodeEnhanceYourCalm    http2ErrCode = 0xb
-	http2ErrCodeInadequateSecurity http2ErrCode = 0xc
-	http2ErrCodeHTTP11Required     http2ErrCode = 0xd
-)
-
-var http2errCodeName = map[http2ErrCode]string{
-	http2ErrCodeNo:                 "NO_ERROR",
-	http2ErrCodeProtocol:           "PROTOCOL_ERROR",
-	http2ErrCodeInternal:           "INTERNAL_ERROR",
-	http2ErrCodeFlowControl:        "FLOW_CONTROL_ERROR",
-	http2ErrCodeSettingsTimeout:    "SETTINGS_TIMEOUT",
-	http2ErrCodeStreamClosed:       "STREAM_CLOSED",
-	http2ErrCodeFrameSize:          "FRAME_SIZE_ERROR",
-	http2ErrCodeRefusedStream:      "REFUSED_STREAM",
-	http2ErrCodeCancel:             "CANCEL",
-	http2ErrCodeCompression:        "COMPRESSION_ERROR",
-	http2ErrCodeConnect:            "CONNECT_ERROR",
-	http2ErrCodeEnhanceYourCalm:    "ENHANCE_YOUR_CALM",
-	http2ErrCodeInadequateSecurity: "INADEQUATE_SECURITY",
-	http2ErrCodeHTTP11Required:     "HTTP_1_1_REQUIRED",
-}
-
-func (e http2ErrCode) String() string {
-	if s, ok := http2errCodeName[e]; ok {
-		return s
-	}
-	return fmt.Sprintf("unknown error code 0x%x", uint32(e))
-}
-
-func (e http2ErrCode) stringToken() string {
-	if s, ok := http2errCodeName[e]; ok {
-		return s
-	}
-	return fmt.Sprintf("ERR_UNKNOWN_%d", uint32(e))
-}
-
-// ConnectionError is an error that results in the termination of the
-// entire connection.
-type http2ConnectionError http2ErrCode
-
-func (e http2ConnectionError) Error() string {
-	return fmt.Sprintf("connection error: %s", http2ErrCode(e))
-}
-
-// StreamError is an error that only affects one stream within an
-// HTTP/2 connection.
-type http2StreamError struct {
-	StreamID uint32
-	Code     http2ErrCode
-	Cause    error // optional additional detail
-}
-
-// errFromPeer is a sentinel error value for StreamError.Cause to
-// indicate that the StreamError was sent from the peer over the wire
-// and wasn't locally generated in the Transport.
-var http2errFromPeer = errors.New("received from peer")
-
-func http2streamError(id uint32, code http2ErrCode) http2StreamError {
-	return http2StreamError{StreamID: id, Code: code}
-}
-
-func (e http2StreamError) Error() string {
-	if e.Cause != nil {
-		return fmt.Sprintf("stream error: stream ID %d; %v; %v", e.StreamID, e.Code, e.Cause)
-	}
-	return fmt.Sprintf("stream error: stream ID %d; %v", e.StreamID, e.Code)
-}
-
-// 6.9.1 The Flow Control Window
-// "If a sender receives a WINDOW_UPDATE that causes a flow control
-// window to exceed this maximum it MUST terminate either the stream
-// or the connection, as appropriate. For streams, [...]; for the
-// connection, a GOAWAY frame with a FLOW_CONTROL_ERROR code."
-type http2goAwayFlowError struct{}
-
-func (http2goAwayFlowError) Error() string { return "connection exceeded flow control window size" }
-
-// connError represents an HTTP/2 ConnectionError error code, along
-// with a string (for debugging) explaining why.
-//
-// Errors of this type are only returned by the frame parser functions
-// and converted into ConnectionError(Code), after stashing away
-// the Reason into the Framer's errDetail field, accessible via
-// the (*Framer).ErrorDetail method.
-type http2connError struct {
-	Code   http2ErrCode // the ConnectionError error code
-	Reason string       // additional reason
-}
-
-func (e http2connError) Error() string {
-	return fmt.Sprintf("http2: connection error: %v: %v", e.Code, e.Reason)
-}
-
-type http2pseudoHeaderError string
-
-func (e http2pseudoHeaderError) Error() string {
-	return fmt.Sprintf("invalid pseudo-header %q", string(e))
-}
-
-type http2duplicatePseudoHeaderError string
-
-func (e http2duplicatePseudoHeaderError) Error() string {
-	return fmt.Sprintf("duplicate pseudo-header %q", string(e))
-}
-
-type http2headerFieldNameError string
-
-func (e http2headerFieldNameError) Error() string {
-	return fmt.Sprintf("invalid header field name %q", string(e))
-}
-
-type http2headerFieldValueError string
-
-func (e http2headerFieldValueError) Error() string {
-	return fmt.Sprintf("invalid header field value %q", string(e))
-}
-
-var (
-	http2errMixPseudoHeaderTypes = errors.New("mix of request and response pseudo headers")
-	http2errPseudoAfterRegular   = errors.New("pseudo header field after regular")
-)
-
-// flow is the flow control window's size.
-type http2flow struct {
-	_ http2incomparable
-
-	// n is the number of DATA bytes we're allowed to send.
-	// A flow is kept both on a conn and a per-stream.
-	n int32
-
-	// conn points to the shared connection-level flow that is
-	// shared by all streams on that conn. It is nil for the flow
-	// that's on the conn directly.
-	conn *http2flow
-}
-
-func (f *http2flow) setConnFlow(cf *http2flow) { f.conn = cf }
-
-func (f *http2flow) available() int32 {
-	n := f.n
-	if f.conn != nil && f.conn.n < n {
-		n = f.conn.n
-	}
-	return n
-}
-
-func (f *http2flow) take(n int32) {
-	if n > f.available() {
-		panic("internal error: took too much")
-	}
-	f.n -= n
-	if f.conn != nil {
-		f.conn.n -= n
-	}
-}
-
-// add adds n bytes (positive or negative) to the flow control window.
-// It returns false if the sum would exceed 2^31-1.
-func (f *http2flow) add(n int32) bool {
-	sum := f.n + n
-	if (sum > n) == (f.n > 0) {
-		f.n = sum
-		return true
-	}
-	return false
-}
-
-const http2frameHeaderLen = 9
-
-var http2padZeros = make([]byte, 255) // zeros for padding
-
-// A FrameType is a registered frame type as defined in
-// http://http2.github.io/http2-spec/#rfc.section.11.2
-type http2FrameType uint8
-
-const (
-	http2FrameData         http2FrameType = 0x0
-	http2FrameHeaders      http2FrameType = 0x1
-	http2FramePriority     http2FrameType = 0x2
-	http2FrameRSTStream    http2FrameType = 0x3
-	http2FrameSettings     http2FrameType = 0x4
-	http2FramePushPromise  http2FrameType = 0x5
-	http2FramePing         http2FrameType = 0x6
-	http2FrameGoAway       http2FrameType = 0x7
-	http2FrameWindowUpdate http2FrameType = 0x8
-	http2FrameContinuation http2FrameType = 0x9
-)
-
-var http2frameName = map[http2FrameType]string{
-	http2FrameData:         "DATA",
-	http2FrameHeaders:      "HEADERS",
-	http2FramePriority:     "PRIORITY",
-	http2FrameRSTStream:    "RST_STREAM",
-	http2FrameSettings:     "SETTINGS",
-	http2FramePushPromise:  "PUSH_PROMISE",
-	http2FramePing:         "PING",
-	http2FrameGoAway:       "GOAWAY",
-	http2FrameWindowUpdate: "WINDOW_UPDATE",
-	http2FrameContinuation: "CONTINUATION",
-}
-
-func (t http2FrameType) String() string {
-	if s, ok := http2frameName[t]; ok {
-		return s
-	}
-	return fmt.Sprintf("UNKNOWN_FRAME_TYPE_%d", uint8(t))
-}
-
-// Flags is a bitmask of HTTP/2 flags.
-// The meaning of flags varies depending on the frame type.
-type http2Flags uint8
-
-// Has reports whether f contains all (0 or more) flags in v.
-func (f http2Flags) Has(v http2Flags) bool {
-	return (f & v) == v
-}
-
-// Frame-specific FrameHeader flag bits.
-const (
-	// Data Frame
-	http2FlagDataEndStream http2Flags = 0x1
-	http2FlagDataPadded    http2Flags = 0x8
-
-	// Headers Frame
-	http2FlagHeadersEndStream  http2Flags = 0x1
-	http2FlagHeadersEndHeaders http2Flags = 0x4
-	http2FlagHeadersPadded     http2Flags = 0x8
-	http2FlagHeadersPriority   http2Flags = 0x20
-
-	// Settings Frame
-	http2FlagSettingsAck http2Flags = 0x1
-
-	// Ping Frame
-	http2FlagPingAck http2Flags = 0x1
-
-	// Continuation Frame
-	http2FlagContinuationEndHeaders http2Flags = 0x4
-
-	http2FlagPushPromiseEndHeaders http2Flags = 0x4
-	http2FlagPushPromisePadded     http2Flags = 0x8
-)
-
-var http2flagName = map[http2FrameType]map[http2Flags]string{
-	http2FrameData: {
-		http2FlagDataEndStream: "END_STREAM",
-		http2FlagDataPadded:    "PADDED",
-	},
-	http2FrameHeaders: {
-		http2FlagHeadersEndStream:  "END_STREAM",
-		http2FlagHeadersEndHeaders: "END_HEADERS",
-		http2FlagHeadersPadded:     "PADDED",
-		http2FlagHeadersPriority:   "PRIORITY",
-	},
-	http2FrameSettings: {
-		http2FlagSettingsAck: "ACK",
-	},
-	http2FramePing: {
-		http2FlagPingAck: "ACK",
-	},
-	http2FrameContinuation: {
-		http2FlagContinuationEndHeaders: "END_HEADERS",
-	},
-	http2FramePushPromise: {
-		http2FlagPushPromiseEndHeaders: "END_HEADERS",
-		http2FlagPushPromisePadded:     "PADDED",
-	},
-}
-
-// a frameParser parses a frame given its FrameHeader and payload
-// bytes. The length of payload will always equal fh.Length (which
-// might be 0).
-type http2frameParser func(fc *http2frameCache, fh http2FrameHeader, countError func(string), payload []byte) (http2Frame, error)
-
-var http2frameParsers = map[http2FrameType]http2frameParser{
-	http2FrameData:         http2parseDataFrame,
-	http2FrameHeaders:      http2parseHeadersFrame,
-	http2FramePriority:     http2parsePriorityFrame,
-	http2FrameRSTStream:    http2parseRSTStreamFrame,
-	http2FrameSettings:     http2parseSettingsFrame,
-	http2FramePushPromise:  http2parsePushPromise,
-	http2FramePing:         http2parsePingFrame,
-	http2FrameGoAway:       http2parseGoAwayFrame,
-	http2FrameWindowUpdate: http2parseWindowUpdateFrame,
-	http2FrameContinuation: http2parseContinuationFrame,
-}
-
-func http2typeFrameParser(t http2FrameType) http2frameParser {
-	if f := http2frameParsers[t]; f != nil {
-		return f
-	}
-	return http2parseUnknownFrame
-}
-
-// A FrameHeader is the 9 byte header of all HTTP/2 frames.
-//
-// See http://http2.github.io/http2-spec/#FrameHeader
-type http2FrameHeader struct {
-	valid bool // caller can access []byte fields in the Frame
-
-	// Type is the 1 byte frame type. There are ten standard frame
-	// types, but extension frame types may be written by WriteRawFrame
-	// and will be returned by ReadFrame (as UnknownFrame).
-	Type http2FrameType
-
-	// Flags are the 1 byte of 8 potential bit flags per frame.
-	// They are specific to the frame type.
-	Flags http2Flags
-
-	// Length is the length of the frame, not including the 9 byte header.
-	// The maximum size is one byte less than 16MB (uint24), but only
-	// frames up to 16KB are allowed without peer agreement.
-	Length uint32
-
-	// StreamID is which stream this frame is for. Certain frames
-	// are not stream-specific, in which case this field is 0.
-	StreamID uint32
-}
-
-// Header returns h. It exists so FrameHeaders can be embedded in other
-// specific frame types and implement the Frame interface.
-func (h http2FrameHeader) Header() http2FrameHeader { return h }
-
-func (h http2FrameHeader) String() string {
-	var buf bytes.Buffer
-	buf.WriteString("[FrameHeader ")
-	h.writeDebug(&buf)
-	buf.WriteByte(']')
-	return buf.String()
-}
-
-func (h http2FrameHeader) writeDebug(buf *bytes.Buffer) {
-	buf.WriteString(h.Type.String())
-	if h.Flags != 0 {
-		buf.WriteString(" flags=")
-		set := 0
-		for i := uint8(0); i < 8; i++ {
-			if h.Flags&(1<<i) == 0 {
-				continue
-			}
-			set++
-			if set > 1 {
-				buf.WriteByte('|')
-			}
-			name := http2flagName[h.Type][http2Flags(1<<i)]
-			if name != "" {
-				buf.WriteString(name)
-			} else {
-				fmt.Fprintf(buf, "0x%x", 1<<i)
-			}
-		}
-	}
-	if h.StreamID != 0 {
-		fmt.Fprintf(buf, " stream=%d", h.StreamID)
-	}
-	fmt.Fprintf(buf, " len=%d", h.Length)
-}
-
-func (h *http2FrameHeader) checkValid() {
-	if !h.valid {
-		panic("Frame accessor called on non-owned Frame")
-	}
-}
-
-func (h *http2FrameHeader) invalidate() { h.valid = false }
-
-// frame header bytes.
-// Used only by ReadFrameHeader.
-var http2fhBytes = sync.Pool{
-	New: func() interface{} {
-		buf := make([]byte, http2frameHeaderLen)
-		return &buf
-	},
-}
-
-// ReadFrameHeader reads 9 bytes from r and returns a FrameHeader.
-// Most users should use Framer.ReadFrame instead.
-func http2ReadFrameHeader(r io.Reader) (http2FrameHeader, error) {
-	bufp := http2fhBytes.Get().(*[]byte)
-	defer http2fhBytes.Put(bufp)
-	return http2readFrameHeader(*bufp, r)
-}
-
-func http2readFrameHeader(buf []byte, r io.Reader) (http2FrameHeader, error) {
-	_, err := io.ReadFull(r, buf[:http2frameHeaderLen])
-	if err != nil {
-		return http2FrameHeader{}, err
-	}
-	return http2FrameHeader{
-		Length:   (uint32(buf[0])<<16 | uint32(buf[1])<<8 | uint32(buf[2])),
-		Type:     http2FrameType(buf[3]),
-		Flags:    http2Flags(buf[4]),
-		StreamID: binary.BigEndian.Uint32(buf[5:]) & (1<<31 - 1),
-		valid:    true,
-	}, nil
-}
-
-// A Frame is the base interface implemented by all frame types.
-// Callers will generally type-assert the specific frame type:
-// *HeadersFrame, *SettingsFrame, *WindowUpdateFrame, etc.
-//
-// Frames are only valid until the next call to Framer.ReadFrame.
-type http2Frame interface {
-	Header() http2FrameHeader
-
-	// invalidate is called by Framer.ReadFrame to make this
-	// frame's buffers as being invalid, since the subsequent
-	// frame will reuse them.
-	invalidate()
-}
-
-// A Framer reads and writes Frames.
-type http2Framer struct {
-	r         io.Reader
-	lastFrame http2Frame
-	errDetail error
-
-	// countError is a non-nil func that's called on a frame parse
-	// error with some unique error path token. It's initialized
-	// from Transport.CountError or Server.CountError.
-	countError func(errToken string)
-
-	// lastHeaderStream is non-zero if the last frame was an
-	// unfinished HEADERS/CONTINUATION.
-	lastHeaderStream uint32
-
-	maxReadSize uint32
-	headerBuf   [http2frameHeaderLen]byte
-
-	// TODO: let getReadBuf be configurable, and use a less memory-pinning
-	// allocator in server.go to minimize memory pinned for many idle conns.
-	// Will probably also need to make frame invalidation have a hook too.
-	getReadBuf func(size uint32) []byte
-	readBuf    []byte // cache for default getReadBuf
-
-	maxWriteSize uint32 // zero means unlimited; TODO: implement
-
-	w    io.Writer
-	wbuf []byte
-
-	// AllowIllegalWrites permits the Framer's Write methods to
-	// write frames that do not conform to the HTTP/2 spec. This
-	// permits using the Framer to test other HTTP/2
-	// implementations' conformance to the spec.
-	// If false, the Write methods will prefer to return an error
-	// rather than comply.
-	AllowIllegalWrites bool
-
-	// AllowIllegalReads permits the Framer's ReadFrame method
-	// to return non-compliant frames or frame orders.
-	// This is for testing and permits using the Framer to test
-	// other HTTP/2 implementations' conformance to the spec.
-	// It is not compatible with ReadMetaHeaders.
-	AllowIllegalReads bool
-
-	// ReadMetaHeaders if non-nil causes ReadFrame to merge
-	// HEADERS and CONTINUATION frames together and return
-	// MetaHeadersFrame instead.
-	ReadMetaHeaders *hpack.Decoder
-
-	// MaxHeaderListSize is the http2 MAX_HEADER_LIST_SIZE.
-	// It's used only if ReadMetaHeaders is set; 0 means a sane default
-	// (currently 16MB)
-	// If the limit is hit, MetaHeadersFrame.Truncated is set true.
-	MaxHeaderListSize uint32
-
-	// TODO: track which type of frame & with which flags was sent
-	// last. Then return an error (unless AllowIllegalWrites) if
-	// we're in the middle of a header block and a
-	// non-Continuation or Continuation on a different stream is
-	// attempted to be written.
-
-	logReads, logWrites bool
-
-	debugFramer       *http2Framer // only use for logging written writes
-	debugFramerBuf    *bytes.Buffer
-	debugReadLoggerf  func(string, ...interface{})
-	debugWriteLoggerf func(string, ...interface{})
-
-	frameCache *http2frameCache // nil if frames aren't reused (default)
-}
-
-func (fr *http2Framer) maxHeaderListSize() uint32 {
-	if fr.MaxHeaderListSize == 0 {
-		return 16 << 20 // sane default, per docs
-	}
-	return fr.MaxHeaderListSize
-}
-
-func (f *http2Framer) startWrite(ftype http2FrameType, flags http2Flags, streamID uint32) {
-	// Write the FrameHeader.
-	f.wbuf = append(f.wbuf[:0],
-		0, // 3 bytes of length, filled in in endWrite
-		0,
-		0,
-		byte(ftype),
-		byte(flags),
-		byte(streamID>>24),
-		byte(streamID>>16),
-		byte(streamID>>8),
-		byte(streamID))
-}
-
-func (f *http2Framer) endWrite() error {
-	// Now that we know the final size, fill in the FrameHeader in
-	// the space previously reserved for it. Abuse append.
-	length := len(f.wbuf) - http2frameHeaderLen
-	if length >= (1 << 24) {
-		return http2ErrFrameTooLarge
-	}
-	_ = append(f.wbuf[:0],
-		byte(length>>16),
-		byte(length>>8),
-		byte(length))
-	if f.logWrites {
-		f.logWrite()
-	}
-
-	n, err := f.w.Write(f.wbuf)
-	if err == nil && n != len(f.wbuf) {
-		err = io.ErrShortWrite
-	}
-	return err
-}
-
-func (f *http2Framer) logWrite() {
-	if f.debugFramer == nil {
-		f.debugFramerBuf = new(bytes.Buffer)
-		f.debugFramer = http2NewFramer(nil, f.debugFramerBuf)
-		f.debugFramer.logReads = false // we log it ourselves, saying "wrote" below
-		// Let us read anything, even if we accidentally wrote it
-		// in the wrong order:
-		f.debugFramer.AllowIllegalReads = true
-	}
-	f.debugFramerBuf.Write(f.wbuf)
-	fr, err := f.debugFramer.ReadFrame()
-	if err != nil {
-		f.debugWriteLoggerf("http2: Framer %p: failed to decode just-written frame", f)
-		return
-	}
-	f.debugWriteLoggerf("http2: Framer %p: wrote %v", f, http2summarizeFrame(fr))
-}
-
-func (f *http2Framer) writeByte(v byte) { f.wbuf = append(f.wbuf, v) }
-
-func (f *http2Framer) writeBytes(v []byte) { f.wbuf = append(f.wbuf, v...) }
-
-func (f *http2Framer) writeUint16(v uint16) { f.wbuf = append(f.wbuf, byte(v>>8), byte(v)) }
-
-func (f *http2Framer) writeUint32(v uint32) {
-	f.wbuf = append(f.wbuf, byte(v>>24), byte(v>>16), byte(v>>8), byte(v))
-}
-
-const (
-	http2minMaxFrameSize = 1 << 14
-	http2maxFrameSize    = 1<<24 - 1
-)
-
-// SetReuseFrames allows the Framer to reuse Frames.
-// If called on a Framer, Frames returned by calls to ReadFrame are only
-// valid until the next call to ReadFrame.
-func (fr *http2Framer) SetReuseFrames() {
-	if fr.frameCache != nil {
-		return
-	}
-	fr.frameCache = &http2frameCache{}
-}
-
-type http2frameCache struct {
-	dataFrame http2DataFrame
-}
-
-func (fc *http2frameCache) getDataFrame() *http2DataFrame {
-	if fc == nil {
-		return &http2DataFrame{}
-	}
-	return &fc.dataFrame
-}
-
-// NewFramer returns a Framer that writes frames to w and reads them from r.
-func http2NewFramer(w io.Writer, r io.Reader) *http2Framer {
-	fr := &http2Framer{
-		w:                 w,
-		r:                 r,
-		countError:        func(string) {},
-		logReads:          http2logFrameReads,
-		logWrites:         http2logFrameWrites,
-		debugReadLoggerf:  log.Printf,
-		debugWriteLoggerf: log.Printf,
-	}
-	fr.getReadBuf = func(size uint32) []byte {
-		if cap(fr.readBuf) >= int(size) {
-			return fr.readBuf[:size]
-		}
-		fr.readBuf = make([]byte, size)
-		return fr.readBuf
-	}
-	fr.SetMaxReadFrameSize(http2maxFrameSize)
-	return fr
-}
-
-// SetMaxReadFrameSize sets the maximum size of a frame
-// that will be read by a subsequent call to ReadFrame.
-// It is the caller's responsibility to advertise this
-// limit with a SETTINGS frame.
-func (fr *http2Framer) SetMaxReadFrameSize(v uint32) {
-	if v > http2maxFrameSize {
-		v = http2maxFrameSize
-	}
-	fr.maxReadSize = v
-}
-
-// ErrorDetail returns a more detailed error of the last error
-// returned by Framer.ReadFrame. For instance, if ReadFrame
-// returns a StreamError with code PROTOCOL_ERROR, ErrorDetail
-// will say exactly what was invalid. ErrorDetail is not guaranteed
-// to return a non-nil value and like the rest of the http2 package,
-// its return value is not protected by an API compatibility promise.
-// ErrorDetail is reset after the next call to ReadFrame.
-func (fr *http2Framer) ErrorDetail() error {
-	return fr.errDetail
-}
-
-// ErrFrameTooLarge is returned from Framer.ReadFrame when the peer
-// sends a frame that is larger than declared with SetMaxReadFrameSize.
-var http2ErrFrameTooLarge = errors.New("http2: frame too large")
-
-// terminalReadFrameError reports whether err is an unrecoverable
-// error from ReadFrame and no other frames should be read.
-func http2terminalReadFrameError(err error) bool {
-	if _, ok := err.(http2StreamError); ok {
-		return false
-	}
-	return err != nil
-}
-
-// ReadFrame reads a single frame. The returned Frame is only valid
-// until the next call to ReadFrame.
-//
-// If the frame is larger than previously set with SetMaxReadFrameSize, the
-// returned error is ErrFrameTooLarge. Other errors may be of type
-// ConnectionError, StreamError, or anything else from the underlying
-// reader.
-func (fr *http2Framer) ReadFrame() (http2Frame, error) {
-	fr.errDetail = nil
-	if fr.lastFrame != nil {
-		fr.lastFrame.invalidate()
-	}
-	fh, err := http2readFrameHeader(fr.headerBuf[:], fr.r)
-	if err != nil {
-		return nil, err
-	}
-	if fh.Length > fr.maxReadSize {
-		return nil, http2ErrFrameTooLarge
-	}
-	payload := fr.getReadBuf(fh.Length)
-	if _, err := io.ReadFull(fr.r, payload); err != nil {
-		return nil, err
-	}
-	f, err := http2typeFrameParser(fh.Type)(fr.frameCache, fh, fr.countError, payload)
-	if err != nil {
-		if ce, ok := err.(http2connError); ok {
-			return nil, fr.connError(ce.Code, ce.Reason)
-		}
-		return nil, err
-	}
-	if err := fr.checkFrameOrder(f); err != nil {
-		return nil, err
-	}
-	if fr.logReads {
-		fr.debugReadLoggerf("http2: Framer %p: read %v", fr, http2summarizeFrame(f))
-	}
-	if fh.Type == http2FrameHeaders && fr.ReadMetaHeaders != nil {
-		return fr.readMetaFrame(f.(*http2HeadersFrame))
-	}
-	return f, nil
-}
-
-// connError returns ConnectionError(code) but first
-// stashes away a public reason to the caller can optionally relay it
-// to the peer before hanging up on them. This might help others debug
-// their implementations.
-func (fr *http2Framer) connError(code http2ErrCode, reason string) error {
-	fr.errDetail = errors.New(reason)
-	return http2ConnectionError(code)
-}
-
-// checkFrameOrder reports an error if f is an invalid frame to return
-// next from ReadFrame. Mostly it checks whether HEADERS and
-// CONTINUATION frames are contiguous.
-func (fr *http2Framer) checkFrameOrder(f http2Frame) error {
-	last := fr.lastFrame
-	fr.lastFrame = f
-	if fr.AllowIllegalReads {
-		return nil
-	}
-
-	fh := f.Header()
-	if fr.lastHeaderStream != 0 {
-		if fh.Type != http2FrameContinuation {
-			return fr.connError(http2ErrCodeProtocol,
-				fmt.Sprintf("got %s for stream %d; expected CONTINUATION following %s for stream %d",
-					fh.Type, fh.StreamID,
-					last.Header().Type, fr.lastHeaderStream))
-		}
-		if fh.StreamID != fr.lastHeaderStream {
-			return fr.connError(http2ErrCodeProtocol,
-				fmt.Sprintf("got CONTINUATION for stream %d; expected stream %d",
-					fh.StreamID, fr.lastHeaderStream))
-		}
-	} else if fh.Type == http2FrameContinuation {
-		return fr.connError(http2ErrCodeProtocol, fmt.Sprintf("unexpected CONTINUATION for stream %d", fh.StreamID))
-	}
-
-	switch fh.Type {
-	case http2FrameHeaders, http2FrameContinuation:
-		if fh.Flags.Has(http2FlagHeadersEndHeaders) {
-			fr.lastHeaderStream = 0
-		} else {
-			fr.lastHeaderStream = fh.StreamID
-		}
-	}
-
-	return nil
-}
-
-// A DataFrame conveys arbitrary, variable-length sequences of octets
-// associated with a stream.
-// See http://http2.github.io/http2-spec/#rfc.section.6.1
-type http2DataFrame struct {
-	http2FrameHeader
-	data []byte
-}
-
-func (f *http2DataFrame) StreamEnded() bool {
-	return f.http2FrameHeader.Flags.Has(http2FlagDataEndStream)
-}
-
-// Data returns the frame's data octets, not including any padding
-// size byte or padding suffix bytes.
-// The caller must not retain the returned memory past the next
-// call to ReadFrame.
-func (f *http2DataFrame) Data() []byte {
-	f.checkValid()
-	return f.data
-}
-
-func http2parseDataFrame(fc *http2frameCache, fh http2FrameHeader, countError func(string), payload []byte) (http2Frame, error) {
-	if fh.StreamID == 0 {
-		// DATA frames MUST be associated with a stream. If a
-		// DATA frame is received whose stream identifier
-		// field is 0x0, the recipient MUST respond with a
-		// connection error (Section 5.4.1) of type
-		// PROTOCOL_ERROR.
-		countError("frame_data_stream_0")
-		return nil, http2connError{http2ErrCodeProtocol, "DATA frame with stream ID 0"}
-	}
-	f := fc.getDataFrame()
-	f.http2FrameHeader = fh
-
-	var padSize byte
-	if fh.Flags.Has(http2FlagDataPadded) {
-		var err error
-		payload, padSize, err = http2readByte(payload)
-		if err != nil {
-			countError("frame_data_pad_byte_short")
-			return nil, err
-		}
-	}
-	if int(padSize) > len(payload) {
-		// If the length of the padding is greater than the
-		// length of the frame payload, the recipient MUST
-		// treat this as a connection error.
-		// Filed: https://github.com/http2/http2-spec/issues/610
-		countError("frame_data_pad_too_big")
-		return nil, http2connError{http2ErrCodeProtocol, "pad size larger than data payload"}
-	}
-	f.data = payload[:len(payload)-int(padSize)]
-	return f, nil
-}
-
-var (
-	http2errStreamID    = errors.New("invalid stream ID")
-	http2errDepStreamID = errors.New("invalid dependent stream ID")
-	http2errPadLength   = errors.New("pad length too large")
-	http2errPadBytes    = errors.New("padding bytes must all be zeros unless AllowIllegalWrites is enabled")
-)
-
-func http2validStreamIDOrZero(streamID uint32) bool {
-	return streamID&(1<<31) == 0
-}
-
-func http2validStreamID(streamID uint32) bool {
-	return streamID != 0 && streamID&(1<<31) == 0
-}
-
-// WriteData writes a DATA frame.
-//
-// It will perform exactly one Write to the underlying Writer.
-// It is the caller's responsibility not to violate the maximum frame size
-// and to not call other Write methods concurrently.
-func (f *http2Framer) WriteData(streamID uint32, endStream bool, data []byte) error {
-	return f.WriteDataPadded(streamID, endStream, data, nil)
-}
-
-// WriteDataPadded writes a DATA frame with optional padding.
-//
-// If pad is nil, the padding bit is not sent.
-// The length of pad must not exceed 255 bytes.
-// The bytes of pad must all be zero, unless f.AllowIllegalWrites is set.
-//
-// It will perform exactly one Write to the underlying Writer.
-// It is the caller's responsibility not to violate the maximum frame size
-// and to not call other Write methods concurrently.
-func (f *http2Framer) WriteDataPadded(streamID uint32, endStream bool, data, pad []byte) error {
-	if !http2validStreamID(streamID) && !f.AllowIllegalWrites {
-		return http2errStreamID
-	}
-	if len(pad) > 0 {
-		if len(pad) > 255 {
-			return http2errPadLength
-		}
-		if !f.AllowIllegalWrites {
-			for _, b := range pad {
-				if b != 0 {
-					// "Padding octets MUST be set to zero when sending."
-					return http2errPadBytes
-				}
-			}
-		}
-	}
-	var flags http2Flags
-	if endStream {
-		flags |= http2FlagDataEndStream
-	}
-	if pad != nil {
-		flags |= http2FlagDataPadded
-	}
-	f.startWrite(http2FrameData, flags, streamID)
-	if pad != nil {
-		f.wbuf = append(f.wbuf, byte(len(pad)))
-	}
-	f.wbuf = append(f.wbuf, data...)
-	f.wbuf = append(f.wbuf, pad...)
-	return f.endWrite()
-}
-
-// A SettingsFrame conveys configuration parameters that affect how
-// endpoints communicate, such as preferences and constraints on peer
-// behavior.
-//
-// See http://http2.github.io/http2-spec/#SETTINGS
-type http2SettingsFrame struct {
-	http2FrameHeader
-	p []byte
-}
-
-func http2parseSettingsFrame(_ *http2frameCache, fh http2FrameHeader, countError func(string), p []byte) (http2Frame, error) {
-	if fh.Flags.Has(http2FlagSettingsAck) && fh.Length > 0 {
-		// When this (ACK 0x1) bit is set, the payload of the
-		// SETTINGS frame MUST be empty. Receipt of a
-		// SETTINGS frame with the ACK flag set and a length
-		// field value other than 0 MUST be treated as a
-		// connection error (Section 5.4.1) of type
-		// FRAME_SIZE_ERROR.
-		countError("frame_settings_ack_with_length")
-		return nil, http2ConnectionError(http2ErrCodeFrameSize)
-	}
-	if fh.StreamID != 0 {
-		// SETTINGS frames always apply to a connection,
-		// never a single stream. The stream identifier for a
-		// SETTINGS frame MUST be zero (0x0).  If an endpoint
-		// receives a SETTINGS frame whose stream identifier
-		// field is anything other than 0x0, the endpoint MUST
-		// respond with a connection error (Section 5.4.1) of
-		// type PROTOCOL_ERROR.
-		countError("frame_settings_has_stream")
-		return nil, http2ConnectionError(http2ErrCodeProtocol)
-	}
-	if len(p)%6 != 0 {
-		countError("frame_settings_mod_6")
-		// Expecting even number of 6 byte settings.
-		return nil, http2ConnectionError(http2ErrCodeFrameSize)
-	}
-	f := &http2SettingsFrame{http2FrameHeader: fh, p: p}
-	if v, ok := f.Value(http2SettingInitialWindowSize); ok && v > (1<<31)-1 {
-		countError("frame_settings_window_size_too_big")
-		// Values above the maximum flow control window size of 2^31 - 1 MUST
-		// be treated as a connection error (Section 5.4.1) of type
-		// FLOW_CONTROL_ERROR.
-		return nil, http2ConnectionError(http2ErrCodeFlowControl)
-	}
-	return f, nil
-}
-
-func (f *http2SettingsFrame) IsAck() bool {
-	return f.http2FrameHeader.Flags.Has(http2FlagSettingsAck)
-}
-
-func (f *http2SettingsFrame) Value(id http2SettingID) (v uint32, ok bool) {
-	f.checkValid()
-	for i := 0; i < f.NumSettings(); i++ {
-		if s := f.Setting(i); s.ID == id {
-			return s.Val, true
-		}
-	}
-	return 0, false
-}
-
-// Setting returns the setting from the frame at the given 0-based index.
-// The index must be >= 0 and less than f.NumSettings().
-func (f *http2SettingsFrame) Setting(i int) http2Setting {
-	buf := f.p
-	return http2Setting{
-		ID:  http2SettingID(binary.BigEndian.Uint16(buf[i*6 : i*6+2])),
-		Val: binary.BigEndian.Uint32(buf[i*6+2 : i*6+6]),
-	}
-}
-
-func (f *http2SettingsFrame) NumSettings() int { return len(f.p) / 6 }
-
-// HasDuplicates reports whether f contains any duplicate setting IDs.
-func (f *http2SettingsFrame) HasDuplicates() bool {
-	num := f.NumSettings()
-	if num == 0 {
-		return false
-	}
-	// If it's small enough (the common case), just do the n^2
-	// thing and avoid a map allocation.
-	if num < 10 {
-		for i := 0; i < num; i++ {
-			idi := f.Setting(i).ID
-			for j := i + 1; j < num; j++ {
-				idj := f.Setting(j).ID
-				if idi == idj {
-					return true
-				}
-			}
-		}
-		return false
-	}
-	seen := map[http2SettingID]bool{}
-	for i := 0; i < num; i++ {
-		id := f.Setting(i).ID
-		if seen[id] {
-			return true
-		}
-		seen[id] = true
-	}
-	return false
-}
-
-// ForeachSetting runs fn for each setting.
-// It stops and returns the first error.
-func (f *http2SettingsFrame) ForeachSetting(fn func(http2Setting) error) error {
-	f.checkValid()
-	for i := 0; i < f.NumSettings(); i++ {
-		if err := fn(f.Setting(i)); err != nil {
-			return err
-		}
-	}
-	return nil
-}
-
-// WriteSettings writes a SETTINGS frame with zero or more settings
-// specified and the ACK bit not set.
-//
-// It will perform exactly one Write to the underlying Writer.
-// It is the caller's responsibility to not call other Write methods concurrently.
-func (f *http2Framer) WriteSettings(settings ...http2Setting) error {
-	f.startWrite(http2FrameSettings, 0, 0)
-	for _, s := range settings {
-		f.writeUint16(uint16(s.ID))
-		f.writeUint32(s.Val)
-	}
-	return f.endWrite()
-}
-
-// WriteSettingsAck writes an empty SETTINGS frame with the ACK bit set.
-//
-// It will perform exactly one Write to the underlying Writer.
-// It is the caller's responsibility to not call other Write methods concurrently.
-func (f *http2Framer) WriteSettingsAck() error {
-	f.startWrite(http2FrameSettings, http2FlagSettingsAck, 0)
-	return f.endWrite()
-}
-
-// A PingFrame is a mechanism for measuring a minimal round trip time
-// from the sender, as well as determining whether an idle connection
-// is still functional.
-// See http://http2.github.io/http2-spec/#rfc.section.6.7
-type http2PingFrame struct {
-	http2FrameHeader
-	Data [8]byte
-}
-
-func (f *http2PingFrame) IsAck() bool { return f.Flags.Has(http2FlagPingAck) }
-
-func http2parsePingFrame(_ *http2frameCache, fh http2FrameHeader, countError func(string), payload []byte) (http2Frame, error) {
-	if len(payload) != 8 {
-		countError("frame_ping_length")
-		return nil, http2ConnectionError(http2ErrCodeFrameSize)
-	}
-	if fh.StreamID != 0 {
-		countError("frame_ping_has_stream")
-		return nil, http2ConnectionError(http2ErrCodeProtocol)
-	}
-	f := &http2PingFrame{http2FrameHeader: fh}
-	copy(f.Data[:], payload)
-	return f, nil
-}
-
-func (f *http2Framer) WritePing(ack bool, data [8]byte) error {
-	var flags http2Flags
-	if ack {
-		flags = http2FlagPingAck
-	}
-	f.startWrite(http2FramePing, flags, 0)
-	f.writeBytes(data[:])
-	return f.endWrite()
-}
-
-// A GoAwayFrame informs the remote peer to stop creating streams on this connection.
-// See http://http2.github.io/http2-spec/#rfc.section.6.8
-type http2GoAwayFrame struct {
-	http2FrameHeader
-	LastStreamID uint32
-	ErrCode      http2ErrCode
-	debugData    []byte
-}
-
-// DebugData returns any debug data in the GOAWAY frame. Its contents
-// are not defined.
-// The caller must not retain the returned memory past the next
-// call to ReadFrame.
-func (f *http2GoAwayFrame) DebugData() []byte {
-	f.checkValid()
-	return f.debugData
-}
-
-func http2parseGoAwayFrame(_ *http2frameCache, fh http2FrameHeader, countError func(string), p []byte) (http2Frame, error) {
-	if fh.StreamID != 0 {
-		countError("frame_goaway_has_stream")
-		return nil, http2ConnectionError(http2ErrCodeProtocol)
-	}
-	if len(p) < 8 {
-		countError("frame_goaway_short")
-		return nil, http2ConnectionError(http2ErrCodeFrameSize)
-	}
-	return &http2GoAwayFrame{
-		http2FrameHeader: fh,
-		LastStreamID:     binary.BigEndian.Uint32(p[:4]) & (1<<31 - 1),
-		ErrCode:          http2ErrCode(binary.BigEndian.Uint32(p[4:8])),
-		debugData:        p[8:],
-	}, nil
-}
-
-func (f *http2Framer) WriteGoAway(maxStreamID uint32, code http2ErrCode, debugData []byte) error {
-	f.startWrite(http2FrameGoAway, 0, 0)
-	f.writeUint32(maxStreamID & (1<<31 - 1))
-	f.writeUint32(uint32(code))
-	f.writeBytes(debugData)
-	return f.endWrite()
-}
-
-// An UnknownFrame is the frame type returned when the frame type is unknown
-// or no specific frame type parser exists.
-type http2UnknownFrame struct {
-	http2FrameHeader
-	p []byte
-}
-
-// Payload returns the frame's payload (after the header).  It is not
-// valid to call this method after a subsequent call to
-// Framer.ReadFrame, nor is it valid to retain the returned slice.
-// The memory is owned by the Framer and is invalidated when the next
-// frame is read.
-func (f *http2UnknownFrame) Payload() []byte {
-	f.checkValid()
-	return f.p
-}
-
-func http2parseUnknownFrame(_ *http2frameCache, fh http2FrameHeader, countError func(string), p []byte) (http2Frame, error) {
-	return &http2UnknownFrame{fh, p}, nil
-}
-
-// A WindowUpdateFrame is used to implement flow control.
-// See http://http2.github.io/http2-spec/#rfc.section.6.9
-type http2WindowUpdateFrame struct {
-	http2FrameHeader
-	Increment uint32 // never read with high bit set
-}
-
-func http2parseWindowUpdateFrame(_ *http2frameCache, fh http2FrameHeader, countError func(string), p []byte) (http2Frame, error) {
-	if len(p) != 4 {
-		countError("frame_windowupdate_bad_len")
-		return nil, http2ConnectionError(http2ErrCodeFrameSize)
-	}
-	inc := binary.BigEndian.Uint32(p[:4]) & 0x7fffffff // mask off high reserved bit
-	if inc == 0 {
-		// A receiver MUST treat the receipt of a
-		// WINDOW_UPDATE frame with an flow control window
-		// increment of 0 as a stream error (Section 5.4.2) of
-		// type PROTOCOL_ERROR; errors on the connection flow
-		// control window MUST be treated as a connection
-		// error (Section 5.4.1).
-		if fh.StreamID == 0 {
-			countError("frame_windowupdate_zero_inc_conn")
-			return nil, http2ConnectionError(http2ErrCodeProtocol)
-		}
-		countError("frame_windowupdate_zero_inc_stream")
-		return nil, http2streamError(fh.StreamID, http2ErrCodeProtocol)
-	}
-	return &http2WindowUpdateFrame{
-		http2FrameHeader: fh,
-		Increment:        inc,
-	}, nil
-}
-
-// WriteWindowUpdate writes a WINDOW_UPDATE frame.
-// The increment value must be between 1 and 2,147,483,647, inclusive.
-// If the Stream ID is zero, the window update applies to the
-// connection as a whole.
-func (f *http2Framer) WriteWindowUpdate(streamID, incr uint32) error {
-	// "The legal range for the increment to the flow control window is 1 to 2^31-1 (2,147,483,647) octets."
-	if (incr < 1 || incr > 2147483647) && !f.AllowIllegalWrites {
-		return errors.New("illegal window increment value")
-	}
-	f.startWrite(http2FrameWindowUpdate, 0, streamID)
-	f.writeUint32(incr)
-	return f.endWrite()
-}
-
-// A HeadersFrame is used to open a stream and additionally carries a
-// header block fragment.
-type http2HeadersFrame struct {
-	http2FrameHeader
-
-	// Priority is set if FlagHeadersPriority is set in the FrameHeader.
-	Priority http2PriorityParam
-
-	headerFragBuf []byte // not owned
-}
-
-func (f *http2HeadersFrame) HeaderBlockFragment() []byte {
-	f.checkValid()
-	return f.headerFragBuf
-}
-
-func (f *http2HeadersFrame) HeadersEnded() bool {
-	return f.http2FrameHeader.Flags.Has(http2FlagHeadersEndHeaders)
-}
-
-func (f *http2HeadersFrame) StreamEnded() bool {
-	return f.http2FrameHeader.Flags.Has(http2FlagHeadersEndStream)
-}
-
-func (f *http2HeadersFrame) HasPriority() bool {
-	return f.http2FrameHeader.Flags.Has(http2FlagHeadersPriority)
-}
-
-func http2parseHeadersFrame(_ *http2frameCache, fh http2FrameHeader, countError func(string), p []byte) (_ http2Frame, err error) {
-	hf := &http2HeadersFrame{
-		http2FrameHeader: fh,
-	}
-	if fh.StreamID == 0 {
-		// HEADERS frames MUST be associated with a stream. If a HEADERS frame
-		// is received whose stream identifier field is 0x0, the recipient MUST
-		// respond with a connection error (Section 5.4.1) of type
-		// PROTOCOL_ERROR.
-		countError("frame_headers_zero_stream")
-		return nil, http2connError{http2ErrCodeProtocol, "HEADERS frame with stream ID 0"}
-	}
-	var padLength uint8
-	if fh.Flags.Has(http2FlagHeadersPadded) {
-		if p, padLength, err = http2readByte(p); err != nil {
-			countError("frame_headers_pad_short")
-			return
-		}
-	}
-	if fh.Flags.Has(http2FlagHeadersPriority) {
-		var v uint32
-		p, v, err = http2readUint32(p)
-		if err != nil {
-			countError("frame_headers_prio_short")
-			return nil, err
-		}
-		hf.Priority.StreamDep = v & 0x7fffffff
-		hf.Priority.Exclusive = (v != hf.Priority.StreamDep) // high bit was set
-		p, hf.Priority.Weight, err = http2readByte(p)
-		if err != nil {
-			countError("frame_headers_prio_weight_short")
-			return nil, err
-		}
-	}
-	if len(p)-int(padLength) < 0 {
-		countError("frame_headers_pad_too_big")
-		return nil, http2streamError(fh.StreamID, http2ErrCodeProtocol)
-	}
-	hf.headerFragBuf = p[:len(p)-int(padLength)]
-	return hf, nil
-}
-
-// HeadersFrameParam are the parameters for writing a HEADERS frame.
-type http2HeadersFrameParam struct {
-	// StreamID is the required Stream ID to initiate.
-	StreamID uint32
-	// BlockFragment is part (or all) of a Header Block.
-	BlockFragment []byte
-
-	// EndStream indicates that the header block is the last that
-	// the endpoint will send for the identified stream. Setting
-	// this flag causes the stream to enter one of "half closed"
-	// states.
-	EndStream bool
-
-	// EndHeaders indicates that this frame contains an entire
-	// header block and is not followed by any
-	// CONTINUATION frames.
-	EndHeaders bool
-
-	// PadLength is the optional number of bytes of zeros to add
-	// to this frame.
-	PadLength uint8
-
-	// Priority, if non-zero, includes stream priority information
-	// in the HEADER frame.
-	Priority http2PriorityParam
-}
-
-// WriteHeaders writes a single HEADERS frame.
-//
-// This is a low-level header writing method. Encoding headers and
-// splitting them into any necessary CONTINUATION frames is handled
-// elsewhere.
-//
-// It will perform exactly one Write to the underlying Writer.
-// It is the caller's responsibility to not call other Write methods concurrently.
-func (f *http2Framer) WriteHeaders(p http2HeadersFrameParam) error {
-	if !http2validStreamID(p.StreamID) && !f.AllowIllegalWrites {
-		return http2errStreamID
-	}
-	var flags http2Flags
-	if p.PadLength != 0 {
-		flags |= http2FlagHeadersPadded
-	}
-	if p.EndStream {
-		flags |= http2FlagHeadersEndStream
-	}
-	if p.EndHeaders {
-		flags |= http2FlagHeadersEndHeaders
-	}
-	if !p.Priority.IsZero() {
-		flags |= http2FlagHeadersPriority
-	}
-	f.startWrite(http2FrameHeaders, flags, p.StreamID)
-	if p.PadLength != 0 {
-		f.writeByte(p.PadLength)
-	}
-	if !p.Priority.IsZero() {
-		v := p.Priority.StreamDep
-		if !http2validStreamIDOrZero(v) && !f.AllowIllegalWrites {
-			return http2errDepStreamID
-		}
-		if p.Priority.Exclusive {
-			v |= 1 << 31
-		}
-		f.writeUint32(v)
-		f.writeByte(p.Priority.Weight)
-	}
-	f.wbuf = append(f.wbuf, p.BlockFragment...)
-	f.wbuf = append(f.wbuf, http2padZeros[:p.PadLength]...)
-	return f.endWrite()
-}
-
-// A PriorityFrame specifies the sender-advised priority of a stream.
-// See http://http2.github.io/http2-spec/#rfc.section.6.3
-type http2PriorityFrame struct {
-	http2FrameHeader
-	http2PriorityParam
-}
-
-// PriorityParam are the stream prioritzation parameters.
-type http2PriorityParam struct {
-	// StreamDep is a 31-bit stream identifier for the
-	// stream that this stream depends on. Zero means no
-	// dependency.
-	StreamDep uint32
-
-	// Exclusive is whether the dependency is exclusive.
-	Exclusive bool
-
-	// Weight is the stream's zero-indexed weight. It should be
-	// set together with StreamDep, or neither should be set. Per
-	// the spec, "Add one to the value to obtain a weight between
-	// 1 and 256."
-	Weight uint8
-}
-
-func (p http2PriorityParam) IsZero() bool {
-	return p == http2PriorityParam{}
-}
-
-func http2parsePriorityFrame(_ *http2frameCache, fh http2FrameHeader, countError func(string), payload []byte) (http2Frame, error) {
-	if fh.StreamID == 0 {
-		countError("frame_priority_zero_stream")
-		return nil, http2connError{http2ErrCodeProtocol, "PRIORITY frame with stream ID 0"}
-	}
-	if len(payload) != 5 {
-		countError("frame_priority_bad_length")
-		return nil, http2connError{http2ErrCodeFrameSize, fmt.Sprintf("PRIORITY frame payload size was %d; want 5", len(payload))}
-	}
-	v := binary.BigEndian.Uint32(payload[:4])
-	streamID := v & 0x7fffffff // mask off high bit
-	return &http2PriorityFrame{
-		http2FrameHeader: fh,
-		http2PriorityParam: http2PriorityParam{
-			Weight:    payload[4],
-			StreamDep: streamID,
-			Exclusive: streamID != v, // was high bit set?
-		},
-	}, nil
-}
-
-// WritePriority writes a PRIORITY frame.
-//
-// It will perform exactly one Write to the underlying Writer.
-// It is the caller's responsibility to not call other Write methods concurrently.
-func (f *http2Framer) WritePriority(streamID uint32, p http2PriorityParam) error {
-	if !http2validStreamID(streamID) && !f.AllowIllegalWrites {
-		return http2errStreamID
-	}
-	if !http2validStreamIDOrZero(p.StreamDep) {
-		return http2errDepStreamID
-	}
-	f.startWrite(http2FramePriority, 0, streamID)
-	v := p.StreamDep
-	if p.Exclusive {
-		v |= 1 << 31
-	}
-	f.writeUint32(v)
-	f.writeByte(p.Weight)
-	return f.endWrite()
-}
-
-// A RSTStreamFrame allows for abnormal termination of a stream.
-// See http://http2.github.io/http2-spec/#rfc.section.6.4
-type http2RSTStreamFrame struct {
-	http2FrameHeader
-	ErrCode http2ErrCode
-}
-
-func http2parseRSTStreamFrame(_ *http2frameCache, fh http2FrameHeader, countError func(string), p []byte) (http2Frame, error) {
-	if len(p) != 4 {
-		countError("frame_rststream_bad_len")
-		return nil, http2ConnectionError(http2ErrCodeFrameSize)
-	}
-	if fh.StreamID == 0 {
-		countError("frame_rststream_zero_stream")
-		return nil, http2ConnectionError(http2ErrCodeProtocol)
-	}
-	return &http2RSTStreamFrame{fh, http2ErrCode(binary.BigEndian.Uint32(p[:4]))}, nil
-}
-
-// WriteRSTStream writes a RST_STREAM frame.
-//
-// It will perform exactly one Write to the underlying Writer.
-// It is the caller's responsibility to not call other Write methods concurrently.
-func (f *http2Framer) WriteRSTStream(streamID uint32, code http2ErrCode) error {
-	if !http2validStreamID(streamID) && !f.AllowIllegalWrites {
-		return http2errStreamID
-	}
-	f.startWrite(http2FrameRSTStream, 0, streamID)
-	f.writeUint32(uint32(code))
-	return f.endWrite()
-}
-
-// A ContinuationFrame is used to continue a sequence of header block fragments.
-// See http://http2.github.io/http2-spec/#rfc.section.6.10
-type http2ContinuationFrame struct {
-	http2FrameHeader
-	headerFragBuf []byte
-}
-
-func http2parseContinuationFrame(_ *http2frameCache, fh http2FrameHeader, countError func(string), p []byte) (http2Frame, error) {
-	if fh.StreamID == 0 {
-		countError("frame_continuation_zero_stream")
-		return nil, http2connError{http2ErrCodeProtocol, "CONTINUATION frame with stream ID 0"}
-	}
-	return &http2ContinuationFrame{fh, p}, nil
-}
-
-func (f *http2ContinuationFrame) HeaderBlockFragment() []byte {
-	f.checkValid()
-	return f.headerFragBuf
-}
-
-func (f *http2ContinuationFrame) HeadersEnded() bool {
-	return f.http2FrameHeader.Flags.Has(http2FlagContinuationEndHeaders)
-}
-
-// WriteContinuation writes a CONTINUATION frame.
-//
-// It will perform exactly one Write to the underlying Writer.
-// It is the caller's responsibility to not call other Write methods concurrently.
-func (f *http2Framer) WriteContinuation(streamID uint32, endHeaders bool, headerBlockFragment []byte) error {
-	if !http2validStreamID(streamID) && !f.AllowIllegalWrites {
-		return http2errStreamID
-	}
-	var flags http2Flags
-	if endHeaders {
-		flags |= http2FlagContinuationEndHeaders
-	}
-	f.startWrite(http2FrameContinuation, flags, streamID)
-	f.wbuf = append(f.wbuf, headerBlockFragment...)
-	return f.endWrite()
-}
-
-// A PushPromiseFrame is used to initiate a server stream.
-// See http://http2.github.io/http2-spec/#rfc.section.6.6
-type http2PushPromiseFrame struct {
-	http2FrameHeader
-	PromiseID     uint32
-	headerFragBuf []byte // not owned
-}
-
-func (f *http2PushPromiseFrame) HeaderBlockFragment() []byte {
-	f.checkValid()
-	return f.headerFragBuf
-}
-
-func (f *http2PushPromiseFrame) HeadersEnded() bool {
-	return f.http2FrameHeader.Flags.Has(http2FlagPushPromiseEndHeaders)
-}
-
-func http2parsePushPromise(_ *http2frameCache, fh http2FrameHeader, countError func(string), p []byte) (_ http2Frame, err error) {
-	pp := &http2PushPromiseFrame{
-		http2FrameHeader: fh,
-	}
-	if pp.StreamID == 0 {
-		// PUSH_PROMISE frames MUST be associated with an existing,
-		// peer-initiated stream. The stream identifier of a
-		// PUSH_PROMISE frame indicates the stream it is associated
-		// with. If the stream identifier field specifies the value
-		// 0x0, a recipient MUST respond with a connection error
-		// (Section 5.4.1) of type PROTOCOL_ERROR.
-		countError("frame_pushpromise_zero_stream")
-		return nil, http2ConnectionError(http2ErrCodeProtocol)
-	}
-	// The PUSH_PROMISE frame includes optional padding.
-	// Padding fields and flags are identical to those defined for DATA frames
-	var padLength uint8
-	if fh.Flags.Has(http2FlagPushPromisePadded) {
-		if p, padLength, err = http2readByte(p); err != nil {
-			countError("frame_pushpromise_pad_short")
-			return
-		}
-	}
-
-	p, pp.PromiseID, err = http2readUint32(p)
-	if err != nil {
-		countError("frame_pushpromise_promiseid_short")
-		return
-	}
-	pp.PromiseID = pp.PromiseID & (1<<31 - 1)
-
-	if int(padLength) > len(p) {
-		// like the DATA frame, error out if padding is longer than the body.
-		countError("frame_pushpromise_pad_too_big")
-		return nil, http2ConnectionError(http2ErrCodeProtocol)
-	}
-	pp.headerFragBuf = p[:len(p)-int(padLength)]
-	return pp, nil
-}
-
-// PushPromiseParam are the parameters for writing a PUSH_PROMISE frame.
-type http2PushPromiseParam struct {
-	// StreamID is the required Stream ID to initiate.
-	StreamID uint32
-
-	// PromiseID is the required Stream ID which this
-	// Push Promises
-	PromiseID uint32
-
-	// BlockFragment is part (or all) of a Header Block.
-	BlockFragment []byte
-
-	// EndHeaders indicates that this frame contains an entire
-	// header block and is not followed by any
-	// CONTINUATION frames.
-	EndHeaders bool
-
-	// PadLength is the optional number of bytes of zeros to add
-	// to this frame.
-	PadLength uint8
-}
-
-// WritePushPromise writes a single PushPromise Frame.
-//
-// As with Header Frames, This is the low level call for writing
-// individual frames. Continuation frames are handled elsewhere.
-//
-// It will perform exactly one Write to the underlying Writer.
-// It is the caller's responsibility to not call other Write methods concurrently.
-func (f *http2Framer) WritePushPromise(p http2PushPromiseParam) error {
-	if !http2validStreamID(p.StreamID) && !f.AllowIllegalWrites {
-		return http2errStreamID
-	}
-	var flags http2Flags
-	if p.PadLength != 0 {
-		flags |= http2FlagPushPromisePadded
-	}
-	if p.EndHeaders {
-		flags |= http2FlagPushPromiseEndHeaders
-	}
-	f.startWrite(http2FramePushPromise, flags, p.StreamID)
-	if p.PadLength != 0 {
-		f.writeByte(p.PadLength)
-	}
-	if !http2validStreamID(p.PromiseID) && !f.AllowIllegalWrites {
-		return http2errStreamID
-	}
-	f.writeUint32(p.PromiseID)
-	f.wbuf = append(f.wbuf, p.BlockFragment...)
-	f.wbuf = append(f.wbuf, http2padZeros[:p.PadLength]...)
-	return f.endWrite()
-}
-
-// WriteRawFrame writes a raw frame. This can be used to write
-// extension frames unknown to this package.
-func (f *http2Framer) WriteRawFrame(t http2FrameType, flags http2Flags, streamID uint32, payload []byte) error {
-	f.startWrite(t, flags, streamID)
-	f.writeBytes(payload)
-	return f.endWrite()
-}
-
-func http2readByte(p []byte) (remain []byte, b byte, err error) {
-	if len(p) == 0 {
-		return nil, 0, io.ErrUnexpectedEOF
-	}
-	return p[1:], p[0], nil
-}
-
-func http2readUint32(p []byte) (remain []byte, v uint32, err error) {
-	if len(p) < 4 {
-		return nil, 0, io.ErrUnexpectedEOF
-	}
-	return p[4:], binary.BigEndian.Uint32(p[:4]), nil
-}
-
-type http2streamEnder interface {
-	StreamEnded() bool
-}
-
-type http2headersEnder interface {
-	HeadersEnded() bool
-}
-
-type http2headersOrContinuation interface {
-	http2headersEnder
-	HeaderBlockFragment() []byte
-}
-
-// A MetaHeadersFrame is the representation of one HEADERS frame and
-// zero or more contiguous CONTINUATION frames and the decoding of
-// their HPACK-encoded contents.
-//
-// This type of frame does not appear on the wire and is only returned
-// by the Framer when Framer.ReadMetaHeaders is set.
-type http2MetaHeadersFrame struct {
-	*http2HeadersFrame
-
-	// Fields are the fields contained in the HEADERS and
-	// CONTINUATION frames. The underlying slice is owned by the
-	// Framer and must not be retained after the next call to
-	// ReadFrame.
-	//
-	// Fields are guaranteed to be in the correct http2 order and
-	// not have unknown pseudo header fields or invalid header
-	// field names or values. Required pseudo header fields may be
-	// missing, however. Use the MetaHeadersFrame.Pseudo accessor
-	// method access pseudo headers.
-	Fields []hpack.HeaderField
-
-	// Truncated is whether the max header list size limit was hit
-	// and Fields is incomplete. The hpack decoder state is still
-	// valid, however.
-	Truncated bool
-}
-
-// PseudoValue returns the given pseudo header field's value.
-// The provided pseudo field should not contain the leading colon.
-func (mh *http2MetaHeadersFrame) PseudoValue(pseudo string) string {
-	for _, hf := range mh.Fields {
-		if !hf.IsPseudo() {
-			return ""
-		}
-		if hf.Name[1:] == pseudo {
-			return hf.Value
-		}
-	}
-	return ""
-}
-
-// RegularFields returns the regular (non-pseudo) header fields of mh.
-// The caller does not own the returned slice.
-func (mh *http2MetaHeadersFrame) RegularFields() []hpack.HeaderField {
-	for i, hf := range mh.Fields {
-		if !hf.IsPseudo() {
-			return mh.Fields[i:]
-		}
-	}
-	return nil
-}
-
-// PseudoFields returns the pseudo header fields of mh.
-// The caller does not own the returned slice.
-func (mh *http2MetaHeadersFrame) PseudoFields() []hpack.HeaderField {
-	for i, hf := range mh.Fields {
-		if !hf.IsPseudo() {
-			return mh.Fields[:i]
-		}
-	}
-	return mh.Fields
-}
-
-func (mh *http2MetaHeadersFrame) checkPseudos() error {
-	var isRequest, isResponse bool
-	pf := mh.PseudoFields()
-	for i, hf := range pf {
-		switch hf.Name {
-		case ":method", ":path", ":scheme", ":authority":
-			isRequest = true
-		case ":status":
-			isResponse = true
-		default:
-			return http2pseudoHeaderError(hf.Name)
-		}
-		// Check for duplicates.
-		// This would be a bad algorithm, but N is 4.
-		// And this doesn't allocate.
-		for _, hf2 := range pf[:i] {
-			if hf.Name == hf2.Name {
-				return http2duplicatePseudoHeaderError(hf.Name)
-			}
-		}
-	}
-	if isRequest && isResponse {
-		return http2errMixPseudoHeaderTypes
-	}
-	return nil
-}
-
-func (fr *http2Framer) maxHeaderStringLen() int {
-	v := fr.maxHeaderListSize()
-	if uint32(int(v)) == v {
-		return int(v)
-	}
-	// They had a crazy big number for MaxHeaderBytes anyway,
-	// so give them unlimited header lengths:
-	return 0
-}
-
-// readMetaFrame returns 0 or more CONTINUATION frames from fr and
-// merge them into the provided hf and returns a MetaHeadersFrame
-// with the decoded hpack values.
-func (fr *http2Framer) readMetaFrame(hf *http2HeadersFrame) (*http2MetaHeadersFrame, error) {
-	if fr.AllowIllegalReads {
-		return nil, errors.New("illegal use of AllowIllegalReads with ReadMetaHeaders")
-	}
-	mh := &http2MetaHeadersFrame{
-		http2HeadersFrame: hf,
-	}
-	var remainSize = fr.maxHeaderListSize()
-	var sawRegular bool
-
-	var invalid error // pseudo header field errors
-	hdec := fr.ReadMetaHeaders
-	hdec.SetEmitEnabled(true)
-	hdec.SetMaxStringLength(fr.maxHeaderStringLen())
-	hdec.SetEmitFunc(func(hf hpack.HeaderField) {
-		if http2VerboseLogs && fr.logReads {
-			fr.debugReadLoggerf("http2: decoded hpack field %+v", hf)
-		}
-		if !httpguts.ValidHeaderFieldValue(hf.Value) {
-			invalid = http2headerFieldValueError(hf.Value)
-		}
-		isPseudo := strings.HasPrefix(hf.Name, ":")
-		if isPseudo {
-			if sawRegular {
-				invalid = http2errPseudoAfterRegular
-			}
-		} else {
-			sawRegular = true
-			if !http2validWireHeaderFieldName(hf.Name) {
-				invalid = http2headerFieldNameError(hf.Name)
-			}
-		}
-
-		if invalid != nil {
-			hdec.SetEmitEnabled(false)
-			return
-		}
-
-		size := hf.Size()
-		if size > remainSize {
-			hdec.SetEmitEnabled(false)
-			mh.Truncated = true
-			return
-		}
-		remainSize -= size
-
-		mh.Fields = append(mh.Fields, hf)
-	})
-	// Lose reference to MetaHeadersFrame:
-	defer hdec.SetEmitFunc(func(hf hpack.HeaderField) {})
-
-	var hc http2headersOrContinuation = hf
-	for {
-		frag := hc.HeaderBlockFragment()
-		if _, err := hdec.Write(frag); err != nil {
-			return nil, http2ConnectionError(http2ErrCodeCompression)
-		}
-
-		if hc.HeadersEnded() {
-			break
-		}
-		if f, err := fr.ReadFrame(); err != nil {
-			return nil, err
-		} else {
-			hc = f.(*http2ContinuationFrame) // guaranteed by checkFrameOrder
-		}
-	}
-
-	mh.http2HeadersFrame.headerFragBuf = nil
-	mh.http2HeadersFrame.invalidate()
-
-	if err := hdec.Close(); err != nil {
-		return nil, http2ConnectionError(http2ErrCodeCompression)
-	}
-	if invalid != nil {
-		fr.errDetail = invalid
-		if http2VerboseLogs {
-			log.Printf("http2: invalid header: %v", invalid)
-		}
-		return nil, http2StreamError{mh.StreamID, http2ErrCodeProtocol, invalid}
-	}
-	if err := mh.checkPseudos(); err != nil {
-		fr.errDetail = err
-		if http2VerboseLogs {
-			log.Printf("http2: invalid pseudo headers: %v", err)
-		}
-		return nil, http2StreamError{mh.StreamID, http2ErrCodeProtocol, err}
-	}
-	return mh, nil
-}
-
-func http2summarizeFrame(f http2Frame) string {
-	var buf bytes.Buffer
-	f.Header().writeDebug(&buf)
-	switch f := f.(type) {
-	case *http2SettingsFrame:
-		n := 0
-		f.ForeachSetting(func(s http2Setting) error {
-			n++
-			if n == 1 {
-				buf.WriteString(", settings:")
-			}
-			fmt.Fprintf(&buf, " %v=%v,", s.ID, s.Val)
-			return nil
-		})
-		if n > 0 {
-			buf.Truncate(buf.Len() - 1) // remove trailing comma
-		}
-	case *http2DataFrame:
-		data := f.Data()
-		const max = 256
-		if len(data) > max {
-			data = data[:max]
-		}
-		fmt.Fprintf(&buf, " data=%q", data)
-		if len(f.Data()) > max {
-			fmt.Fprintf(&buf, " (%d bytes omitted)", len(f.Data())-max)
-		}
-	case *http2WindowUpdateFrame:
-		if f.StreamID == 0 {
-			buf.WriteString(" (conn)")
-		}
-		fmt.Fprintf(&buf, " incr=%v", f.Increment)
-	case *http2PingFrame:
-		fmt.Fprintf(&buf, " ping=%q", f.Data[:])
-	case *http2GoAwayFrame:
-		fmt.Fprintf(&buf, " LastStreamID=%v ErrCode=%v Debug=%q",
-			f.LastStreamID, f.ErrCode, f.debugData)
-	case *http2RSTStreamFrame:
-		fmt.Fprintf(&buf, " ErrCode=%v", f.ErrCode)
-	}
-	return buf.String()
-}
-
-func http2traceHasWroteHeaderField(trace *httptrace.ClientTrace) bool {
-	return trace != nil && trace.WroteHeaderField != nil
-}
-
-func http2traceWroteHeaderField(trace *httptrace.ClientTrace, k, v string) {
-	if trace != nil && trace.WroteHeaderField != nil {
-		trace.WroteHeaderField(k, []string{v})
-	}
-}
-
-func http2traceGot1xxResponseFunc(trace *httptrace.ClientTrace) func(int, textproto.MIMEHeader) error {
-	if trace != nil {
-		return trace.Got1xxResponse
-	}
-	return nil
-}
-
-// dialTLSWithContext uses tls.Dialer, added in Go 1.15, to open a TLS
-// connection.
-func (t *http2Transport) dialTLSWithContext(ctx context.Context, network, addr string, cfg *tls.Config) (*tls.Conn, error) {
-	dialer := &tls.Dialer{
-		Config: cfg,
-	}
-	cn, err := dialer.DialContext(ctx, network, addr)
-	if err != nil {
-		return nil, err
-	}
-	tlsCn := cn.(*tls.Conn) // DialContext comment promises this will always succeed
-	return tlsCn, nil
-}
-
-var http2DebugGoroutines = os.Getenv("DEBUG_HTTP2_GOROUTINES") == "1"
-
-type http2goroutineLock uint64
-
-func http2newGoroutineLock() http2goroutineLock {
-	if !http2DebugGoroutines {
-		return 0
-	}
-	return http2goroutineLock(http2curGoroutineID())
-}
-
-func (g http2goroutineLock) check() {
-	if !http2DebugGoroutines {
-		return
-	}
-	if http2curGoroutineID() != uint64(g) {
-		panic("running on the wrong goroutine")
-	}
-}
-
-func (g http2goroutineLock) checkNotOn() {
-	if !http2DebugGoroutines {
-		return
-	}
-	if http2curGoroutineID() == uint64(g) {
-		panic("running on the wrong goroutine")
-	}
-}
-
-var http2goroutineSpace = []byte("goroutine ")
-
-func http2curGoroutineID() uint64 {
-	bp := http2littleBuf.Get().(*[]byte)
-	defer http2littleBuf.Put(bp)
-	b := *bp
-	b = b[:runtime.Stack(b, false)]
-	// Parse the 4707 out of "goroutine 4707 ["
-	b = bytes.TrimPrefix(b, http2goroutineSpace)
-	i := bytes.IndexByte(b, ' ')
-	if i < 0 {
-		panic(fmt.Sprintf("No space found in %q", b))
-	}
-	b = b[:i]
-	n, err := http2parseUintBytes(b, 10, 64)
-	if err != nil {
-		panic(fmt.Sprintf("Failed to parse goroutine ID out of %q: %v", b, err))
-	}
-	return n
-}
-
-var http2littleBuf = sync.Pool{
-	New: func() interface{} {
-		buf := make([]byte, 64)
-		return &buf
-	},
-}
-
-// parseUintBytes is like strconv.ParseUint, but using a []byte.
-func http2parseUintBytes(s []byte, base int, bitSize int) (n uint64, err error) {
-	var cutoff, maxVal uint64
-
-	if bitSize == 0 {
-		bitSize = int(strconv.IntSize)
-	}
-
-	s0 := s
-	switch {
-	case len(s) < 1:
-		err = strconv.ErrSyntax
-		goto Error
-
-	case 2 <= base && base <= 36:
-		// valid base; nothing to do
-
-	case base == 0:
-		// Look for octal, hex prefix.
-		switch {
-		case s[0] == '0' && len(s) > 1 && (s[1] == 'x' || s[1] == 'X'):
-			base = 16
-			s = s[2:]
-			if len(s) < 1 {
-				err = strconv.ErrSyntax
-				goto Error
-			}
-		case s[0] == '0':
-			base = 8
-		default:
-			base = 10
-		}
-
-	default:
-		err = errors.New("invalid base " + strconv.Itoa(base))
-		goto Error
-	}
-
-	n = 0
-	cutoff = http2cutoff64(base)
-	maxVal = 1<<uint(bitSize) - 1
-
-	for i := 0; i < len(s); i++ {
-		var v byte
-		d := s[i]
-		switch {
-		case '0' <= d && d <= '9':
-			v = d - '0'
-		case 'a' <= d && d <= 'z':
-			v = d - 'a' + 10
-		case 'A' <= d && d <= 'Z':
-			v = d - 'A' + 10
-		default:
-			n = 0
-			err = strconv.ErrSyntax
-			goto Error
-		}
-		if int(v) >= base {
-			n = 0
-			err = strconv.ErrSyntax
-			goto Error
-		}
-
-		if n >= cutoff {
-			// n*base overflows
-			n = 1<<64 - 1
-			err = strconv.ErrRange
-			goto Error
-		}
-		n *= uint64(base)
-
-		n1 := n + uint64(v)
-		if n1 < n || n1 > maxVal {
-			// n+v overflows
-			n = 1<<64 - 1
-			err = strconv.ErrRange
-			goto Error
-		}
-		n = n1
-	}
-
-	return n, nil
-
-Error:
-	return n, &strconv.NumError{Func: "ParseUint", Num: string(s0), Err: err}
-}
-
-// Return the first number n such that n*base >= 1<<64.
-func http2cutoff64(base int) uint64 {
-	if base < 2 {
-		return 0
-	}
-	return (1<<64-1)/uint64(base) + 1
-}
-
-var (
-	http2commonBuildOnce   sync.Once
-	http2commonLowerHeader map[string]string // Go-Canonical-Case -> lower-case
-	http2commonCanonHeader map[string]string // lower-case -> Go-Canonical-Case
-)
-
-func http2buildCommonHeaderMapsOnce() {
-	http2commonBuildOnce.Do(http2buildCommonHeaderMaps)
-}
-
-func http2buildCommonHeaderMaps() {
-	common := []string{
-		"accept",
-		"accept-charset",
-		"accept-encoding",
-		"accept-language",
-		"accept-ranges",
-		"age",
-		"access-control-allow-origin",
-		"allow",
-		"authorization",
-		"cache-control",
-		"content-disposition",
-		"content-encoding",
-		"content-language",
-		"content-length",
-		"content-location",
-		"content-range",
-		"content-type",
-		"cookie",
-		"date",
-		"etag",
-		"expect",
-		"expires",
-		"from",
-		"host",
-		"if-match",
-		"if-modified-since",
-		"if-none-match",
-		"if-unmodified-since",
-		"last-modified",
-		"link",
-		"location",
-		"max-forwards",
-		"proxy-authenticate",
-		"proxy-authorization",
-		"range",
-		"referer",
-		"refresh",
-		"retry-after",
-		"server",
-		"set-cookie",
-		"strict-transport-security",
-		"trailer",
-		"transfer-encoding",
-		"user-agent",
-		"vary",
-		"via",
-		"www-authenticate",
-	}
-	http2commonLowerHeader = make(map[string]string, len(common))
-	http2commonCanonHeader = make(map[string]string, len(common))
-	for _, v := range common {
-		chk := CanonicalHeaderKey(v)
-		http2commonLowerHeader[chk] = v
-		http2commonCanonHeader[v] = chk
-	}
-}
-
-func http2lowerHeader(v string) (lower string, ascii bool) {
-	http2buildCommonHeaderMapsOnce()
-	if s, ok := http2commonLowerHeader[v]; ok {
-		return s, true
-	}
-	return http2asciiToLower(v)
-}
-
-var (
-	http2VerboseLogs    bool
-	http2logFrameWrites bool
-	http2logFrameReads  bool
-	http2inTests        bool
-)
-
-func init() {
-	e := os.Getenv("GODEBUG")
-	if strings.Contains(e, "http2debug=1") {
-		http2VerboseLogs = true
-	}
-	if strings.Contains(e, "http2debug=2") {
-		http2VerboseLogs = true
-		http2logFrameWrites = true
-		http2logFrameReads = true
-	}
-}
-
-const (
-	// ClientPreface is the string that must be sent by new
-	// connections from clients.
-	http2ClientPreface = "PRI * HTTP/2.0\r\n\r\nSM\r\n\r\n"
-
-	// SETTINGS_MAX_FRAME_SIZE default
-	// http://http2.github.io/http2-spec/#rfc.section.6.5.2
-	http2initialMaxFrameSize = 16384
-
-	// NextProtoTLS is the NPN/ALPN protocol negotiated during
-	// HTTP/2's TLS setup.
-	http2NextProtoTLS = "h2"
-
-	// http://http2.github.io/http2-spec/#SettingValues
-	http2initialHeaderTableSize = 4096
-
-	http2initialWindowSize = 65535 // 6.9.2 Initial Flow Control Window Size
-
-	http2defaultMaxReadFrameSize = 1 << 20
-)
-
-var (
-	http2clientPreface = []byte(http2ClientPreface)
-)
-
-type http2streamState int
-
-// HTTP/2 stream states.
-//
-// See http://tools.ietf.org/html/rfc7540#section-5.1.
-//
-// For simplicity, the server code merges "reserved (local)" into
-// "half-closed (remote)". This is one less state transition to track.
-// The only downside is that we send PUSH_PROMISEs slightly less
-// liberally than allowable. More discussion here:
-// https://lists.w3.org/Archives/Public/ietf-http-wg/2016JulSep/0599.html
-//
-// "reserved (remote)" is omitted since the client code does not
-// support server push.
-const (
-	http2stateIdle http2streamState = iota
-	http2stateOpen
-	http2stateHalfClosedLocal
-	http2stateHalfClosedRemote
-	http2stateClosed
-)
-
-var http2stateName = [...]string{
-	http2stateIdle:             "Idle",
-	http2stateOpen:             "Open",
-	http2stateHalfClosedLocal:  "HalfClosedLocal",
-	http2stateHalfClosedRemote: "HalfClosedRemote",
-	http2stateClosed:           "Closed",
-}
-
-func (st http2streamState) String() string {
-	return http2stateName[st]
-}
-
-// Setting is a setting parameter: which setting it is, and its value.
-type http2Setting struct {
-	// ID is which setting is being set.
-	// See http://http2.github.io/http2-spec/#SettingValues
-	ID http2SettingID
-
-	// Val is the value.
-	Val uint32
-}
-
-func (s http2Setting) String() string {
-	return fmt.Sprintf("[%v = %d]", s.ID, s.Val)
-}
-
-// Valid reports whether the setting is valid.
-func (s http2Setting) Valid() error {
-	// Limits and error codes from 6.5.2 Defined SETTINGS Parameters
-	switch s.ID {
-	case http2SettingEnablePush:
-		if s.Val != 1 && s.Val != 0 {
-			return http2ConnectionError(http2ErrCodeProtocol)
-		}
-	case http2SettingInitialWindowSize:
-		if s.Val > 1<<31-1 {
-			return http2ConnectionError(http2ErrCodeFlowControl)
-		}
-	case http2SettingMaxFrameSize:
-		if s.Val < 16384 || s.Val > 1<<24-1 {
-			return http2ConnectionError(http2ErrCodeProtocol)
-		}
-	}
-	return nil
-}
-
-// A SettingID is an HTTP/2 setting as defined in
-// http://http2.github.io/http2-spec/#iana-settings
-type http2SettingID uint16
-
-const (
-	http2SettingHeaderTableSize      http2SettingID = 0x1
-	http2SettingEnablePush           http2SettingID = 0x2
-	http2SettingMaxConcurrentStreams http2SettingID = 0x3
-	http2SettingInitialWindowSize    http2SettingID = 0x4
-	http2SettingMaxFrameSize         http2SettingID = 0x5
-	http2SettingMaxHeaderListSize    http2SettingID = 0x6
-)
-
-var http2settingName = map[http2SettingID]string{
-	http2SettingHeaderTableSize:      "HEADER_TABLE_SIZE",
-	http2SettingEnablePush:           "ENABLE_PUSH",
-	http2SettingMaxConcurrentStreams: "MAX_CONCURRENT_STREAMS",
-	http2SettingInitialWindowSize:    "INITIAL_WINDOW_SIZE",
-	http2SettingMaxFrameSize:         "MAX_FRAME_SIZE",
-	http2SettingMaxHeaderListSize:    "MAX_HEADER_LIST_SIZE",
-}
-
-func (s http2SettingID) String() string {
-	if v, ok := http2settingName[s]; ok {
-		return v
-	}
-	return fmt.Sprintf("UNKNOWN_SETTING_%d", uint16(s))
-}
-
-// validWireHeaderFieldName reports whether v is a valid header field
-// name (key). See httpguts.ValidHeaderName for the base rules.
-//
-// Further, http2 says:
-//   "Just as in HTTP/1.x, header field names are strings of ASCII
-//   characters that are compared in a case-insensitive
-//   fashion. However, header field names MUST be converted to
-//   lowercase prior to their encoding in HTTP/2. "
-func http2validWireHeaderFieldName(v string) bool {
-	if len(v) == 0 {
-		return false
-	}
-	for _, r := range v {
-		if !httpguts.IsTokenRune(r) {
-			return false
-		}
-		if 'A' <= r && r <= 'Z' {
-			return false
-		}
-	}
-	return true
-}
-
-func http2httpCodeString(code int) string {
-	switch code {
-	case 200:
-		return "200"
-	case 404:
-		return "404"
-	}
-	return strconv.Itoa(code)
-}
-
-// from pkg io
-type http2stringWriter interface {
-	WriteString(s string) (n int, err error)
-}
-
-// A gate lets two goroutines coordinate their activities.
-type http2gate chan struct{}
-
-func (g http2gate) Done() { g <- struct{}{} }
-
-func (g http2gate) Wait() { <-g }
-
-// A closeWaiter is like a sync.WaitGroup but only goes 1 to 0 (open to closed).
-type http2closeWaiter chan struct{}
-
-// Init makes a closeWaiter usable.
-// It exists because so a closeWaiter value can be placed inside a
-// larger struct and have the Mutex and Cond's memory in the same
-// allocation.
-func (cw *http2closeWaiter) Init() {
-	*cw = make(chan struct{})
-}
-
-// Close marks the closeWaiter as closed and unblocks any waiters.
-func (cw http2closeWaiter) Close() {
-	close(cw)
-}
-
-// Wait waits for the closeWaiter to become closed.
-func (cw http2closeWaiter) Wait() {
-	<-cw
-}
-
-// bufferedWriter is a buffered writer that writes to w.
-// Its buffered writer is lazily allocated as needed, to minimize
-// idle memory usage with many connections.
-type http2bufferedWriter struct {
-	_  http2incomparable
-	w  io.Writer     // immutable
-	bw *bufio.Writer // non-nil when data is buffered
-}
-
-func http2newBufferedWriter(w io.Writer) *http2bufferedWriter {
-	return &http2bufferedWriter{w: w}
-}
-
-// bufWriterPoolBufferSize is the size of bufio.Writer's
-// buffers created using bufWriterPool.
-//
-// TODO: pick a less arbitrary value? this is a bit under
-// (3 x typical 1500 byte MTU) at least. Other than that,
-// not much thought went into it.
-const http2bufWriterPoolBufferSize = 4 << 10
-
-var http2bufWriterPool = sync.Pool{
-	New: func() interface{} {
-		return bufio.NewWriterSize(nil, http2bufWriterPoolBufferSize)
-	},
-}
-
-func (w *http2bufferedWriter) Available() int {
-	if w.bw == nil {
-		return http2bufWriterPoolBufferSize
-	}
-	return w.bw.Available()
-}
-
-func (w *http2bufferedWriter) Write(p []byte) (n int, err error) {
-	if w.bw == nil {
-		bw := http2bufWriterPool.Get().(*bufio.Writer)
-		bw.Reset(w.w)
-		w.bw = bw
-	}
-	return w.bw.Write(p)
-}
-
-func (w *http2bufferedWriter) Flush() error {
-	bw := w.bw
-	if bw == nil {
-		return nil
-	}
-	err := bw.Flush()
-	bw.Reset(nil)
-	http2bufWriterPool.Put(bw)
-	w.bw = nil
-	return err
-}
-
-func http2mustUint31(v int32) uint32 {
-	if v < 0 || v > 2147483647 {
-		panic("out of range")
-	}
-	return uint32(v)
-}
-
-// bodyAllowedForStatus reports whether a given response status code
-// permits a body. See RFC 7230, section 3.3.
-func http2bodyAllowedForStatus(status int) bool {
-	switch {
-	case status >= 100 && status <= 199:
-		return false
-	case status == 204:
-		return false
-	case status == 304:
-		return false
-	}
-	return true
-}
-
-type http2httpError struct {
-	_       http2incomparable
-	msg     string
-	timeout bool
-}
-
-func (e *http2httpError) Error() string { return e.msg }
-
-func (e *http2httpError) Timeout() bool { return e.timeout }
-
-func (e *http2httpError) Temporary() bool { return true }
-
-var http2errTimeout error = &http2httpError{msg: "http2: timeout awaiting response headers", timeout: true}
-
-type http2connectionStater interface {
-	ConnectionState() tls.ConnectionState
-}
-
-var http2sorterPool = sync.Pool{New: func() interface{} { return new(http2sorter) }}
-
-type http2sorter struct {
-	v []string // owned by sorter
-}
-
-func (s *http2sorter) Len() int { return len(s.v) }
-
-func (s *http2sorter) Swap(i, j int) { s.v[i], s.v[j] = s.v[j], s.v[i] }
-
-func (s *http2sorter) Less(i, j int) bool { return s.v[i] < s.v[j] }
-
-// Keys returns the sorted keys of h.
-//
-// The returned slice is only valid until s used again or returned to
-// its pool.
-func (s *http2sorter) Keys(h Header) []string {
-	keys := s.v[:0]
-	for k := range h {
-		keys = append(keys, k)
-	}
-	s.v = keys
-	sort.Sort(s)
-	return keys
-}
-
-func (s *http2sorter) SortStrings(ss []string) {
-	// Our sorter works on s.v, which sorter owns, so
-	// stash it away while we sort the user's buffer.
-	save := s.v
-	s.v = ss
-	sort.Sort(s)
-	s.v = save
-}
-
-// validPseudoPath reports whether v is a valid :path pseudo-header
-// value. It must be either:
-//
-//     *) a non-empty string starting with '/'
-//     *) the string '*', for OPTIONS requests.
-//
-// For now this is only used a quick check for deciding when to clean
-// up Opaque URLs before sending requests from the Transport.
-// See golang.org/issue/16847
-//
-// We used to enforce that the path also didn't start with "//", but
-// Google's GFE accepts such paths and Chrome sends them, so ignore
-// that part of the spec. See golang.org/issue/19103.
-func http2validPseudoPath(v string) bool {
-	return (len(v) > 0 && v[0] == '/') || v == "*"
-}
-
-// incomparable is a zero-width, non-comparable type. Adding it to a struct
-// makes that struct also non-comparable, and generally doesn't add
-// any size (as long as it's first).
-type http2incomparable [0]func()
-
-// pipe is a goroutine-safe io.Reader/io.Writer pair. It's like
-// io.Pipe except there are no PipeReader/PipeWriter halves, and the
-// underlying buffer is an interface. (io.Pipe is always unbuffered)
-type http2pipe struct {
-	mu       sync.Mutex
-	c        sync.Cond       // c.L lazily initialized to &p.mu
-	b        http2pipeBuffer // nil when done reading
-	unread   int             // bytes unread when done
-	err      error           // read error once empty. non-nil means closed.
-	breakErr error           // immediate read error (caller doesn't see rest of b)
-	donec    chan struct{}   // closed on error
-	readFn   func()          // optional code to run in Read before error
-}
-
-type http2pipeBuffer interface {
-	Len() int
-	io.Writer
-	io.Reader
-}
-
-// setBuffer initializes the pipe buffer.
-// It has no effect if the pipe is already closed.
-func (p *http2pipe) setBuffer(b http2pipeBuffer) {
-	p.mu.Lock()
-	defer p.mu.Unlock()
-	if p.err != nil || p.breakErr != nil {
-		return
-	}
-	p.b = b
-}
-
-func (p *http2pipe) Len() int {
-	p.mu.Lock()
-	defer p.mu.Unlock()
-	if p.b == nil {
-		return p.unread
-	}
-	return p.b.Len()
-}
-
-// Read waits until data is available and copies bytes
-// from the buffer into p.
-func (p *http2pipe) Read(d []byte) (n int, err error) {
-	p.mu.Lock()
-	defer p.mu.Unlock()
-	if p.c.L == nil {
-		p.c.L = &p.mu
-	}
-	for {
-		if p.breakErr != nil {
-			return 0, p.breakErr
-		}
-		if p.b != nil && p.b.Len() > 0 {
-			return p.b.Read(d)
-		}
-		if p.err != nil {
-			if p.readFn != nil {
-				p.readFn()     // e.g. copy trailers
-				p.readFn = nil // not sticky like p.err
-			}
-			p.b = nil
-			return 0, p.err
-		}
-		p.c.Wait()
-	}
-}
-
-var http2errClosedPipeWrite = errors.New("write on closed buffer")
-
-// Write copies bytes from p into the buffer and wakes a reader.
-// It is an error to write more data than the buffer can hold.
-func (p *http2pipe) Write(d []byte) (n int, err error) {
-	p.mu.Lock()
-	defer p.mu.Unlock()
-	if p.c.L == nil {
-		p.c.L = &p.mu
-	}
-	defer p.c.Signal()
-	if p.err != nil {
-		return 0, http2errClosedPipeWrite
-	}
-	if p.breakErr != nil {
-		p.unread += len(d)
-		return len(d), nil // discard when there is no reader
-	}
-	return p.b.Write(d)
-}
-
-// CloseWithError causes the next Read (waking up a current blocked
-// Read if needed) to return the provided err after all data has been
-// read.
-//
-// The error must be non-nil.
-func (p *http2pipe) CloseWithError(err error) { p.closeWithError(&p.err, err, nil) }
-
-// BreakWithError causes the next Read (waking up a current blocked
-// Read if needed) to return the provided err immediately, without
-// waiting for unread data.
-func (p *http2pipe) BreakWithError(err error) { p.closeWithError(&p.breakErr, err, nil) }
-
-// closeWithErrorAndCode is like CloseWithError but also sets some code to run
-// in the caller's goroutine before returning the error.
-func (p *http2pipe) closeWithErrorAndCode(err error, fn func()) { p.closeWithError(&p.err, err, fn) }
-
-func (p *http2pipe) closeWithError(dst *error, err error, fn func()) {
-	if err == nil {
-		panic("err must be non-nil")
-	}
-	p.mu.Lock()
-	defer p.mu.Unlock()
-	if p.c.L == nil {
-		p.c.L = &p.mu
-	}
-	defer p.c.Signal()
-	if *dst != nil {
-		// Already been done.
-		return
-	}
-	p.readFn = fn
-	if dst == &p.breakErr {
-		if p.b != nil {
-			p.unread += p.b.Len()
-		}
-		p.b = nil
-	}
-	*dst = err
-	p.closeDoneLocked()
-}
-
-// requires p.mu be held.
-func (p *http2pipe) closeDoneLocked() {
-	if p.donec == nil {
-		return
-	}
-	// Close if unclosed. This isn't racy since we always
-	// hold p.mu while closing.
-	select {
-	case <-p.donec:
-	default:
-		close(p.donec)
-	}
-}
-
-// Err returns the error (if any) first set by BreakWithError or CloseWithError.
-func (p *http2pipe) Err() error {
-	p.mu.Lock()
-	defer p.mu.Unlock()
-	if p.breakErr != nil {
-		return p.breakErr
-	}
-	return p.err
-}
-
-// Done returns a channel which is closed if and when this pipe is closed
-// with CloseWithError.
-func (p *http2pipe) Done() <-chan struct{} {
-	p.mu.Lock()
-	defer p.mu.Unlock()
-	if p.donec == nil {
-		p.donec = make(chan struct{})
-		if p.err != nil || p.breakErr != nil {
-			// Already hit an error.
-			p.closeDoneLocked()
-		}
-	}
-	return p.donec
-}
-
-const (
-	http2prefaceTimeout         = 10 * time.Second
-	http2firstSettingsTimeout   = 2 * time.Second // should be in-flight with preface anyway
-	http2handlerChunkWriteSize  = 4 << 10
-	http2defaultMaxStreams      = 250 // TODO: make this 100 as the GFE seems to?
-	http2maxQueuedControlFrames = 10000
-)
-
-var (
-	http2errClientDisconnected = errors.New("client disconnected")
-	http2errClosedBody         = errors.New("body closed by handler")
-	http2errHandlerComplete    = errors.New("http2: request body closed due to handler exiting")
-	http2errStreamClosed       = errors.New("http2: stream closed")
-)
-
-var http2responseWriterStatePool = sync.Pool{
-	New: func() interface{} {
-		rws := &http2responseWriterState{}
-		rws.bw = bufio.NewWriterSize(http2chunkWriter{rws}, http2handlerChunkWriteSize)
-		return rws
-	},
-}
-
-// Test hooks.
-var (
-	http2testHookOnConn        func()
-	http2testHookGetServerConn func(*http2serverConn)
-	http2testHookOnPanicMu     *sync.Mutex // nil except in tests
-	http2testHookOnPanic       func(sc *http2serverConn, panicVal interface{}) (rePanic bool)
-)
-
-// Server is an HTTP/2 server.
-type http2Server struct {
-	// MaxHandlers limits the number of http.Handler ServeHTTP goroutines
-	// which may run at a time over all connections.
-	// Negative or zero no limit.
-	// TODO: implement
-	MaxHandlers int
-
-	// MaxConcurrentStreams optionally specifies the number of
-	// concurrent streams that each client may have open at a
-	// time. This is unrelated to the number of http.Handler goroutines
-	// which may be active globally, which is MaxHandlers.
-	// If zero, MaxConcurrentStreams defaults to at least 100, per
-	// the HTTP/2 spec's recommendations.
-	MaxConcurrentStreams uint32
-
-	// MaxReadFrameSize optionally specifies the largest frame
-	// this server is willing to read. A valid value is between
-	// 16k and 16M, inclusive. If zero or otherwise invalid, a
-	// default value is used.
-	MaxReadFrameSize uint32
-
-	// PermitProhibitedCipherSuites, if true, permits the use of
-	// cipher suites prohibited by the HTTP/2 spec.
-	PermitProhibitedCipherSuites bool
-
-	// IdleTimeout specifies how long until idle clients should be
-	// closed with a GOAWAY frame. PING frames are not considered
-	// activity for the purposes of IdleTimeout.
-	IdleTimeout time.Duration
-
-	// MaxUploadBufferPerConnection is the size of the initial flow
-	// control window for each connections. The HTTP/2 spec does not
-	// allow this to be smaller than 65535 or larger than 2^32-1.
-	// If the value is outside this range, a default value will be
-	// used instead.
-	MaxUploadBufferPerConnection int32
-
-	// MaxUploadBufferPerStream is the size of the initial flow control
-	// window for each stream. The HTTP/2 spec does not allow this to
-	// be larger than 2^32-1. If the value is zero or larger than the
-	// maximum, a default value will be used instead.
-	MaxUploadBufferPerStream int32
-
-	// NewWriteScheduler constructs a write scheduler for a connection.
-	// If nil, a default scheduler is chosen.
-	NewWriteScheduler func() http2WriteScheduler
-
-	// CountError, if non-nil, is called on HTTP/2 server errors.
-	// It's intended to increment a metric for monitoring, such
-	// as an expvar or Prometheus metric.
-	// The errType consists of only ASCII word characters.
-	CountError func(errType string)
-
-	// Internal state. This is a pointer (rather than embedded directly)
-	// so that we don't embed a Mutex in this struct, which will make the
-	// struct non-copyable, which might break some callers.
-	state *http2serverInternalState
-}
-
-func (s *http2Server) initialConnRecvWindowSize() int32 {
-	if s.MaxUploadBufferPerConnection > http2initialWindowSize {
-		return s.MaxUploadBufferPerConnection
-	}
-	return 1 << 20
-}
-
-func (s *http2Server) initialStreamRecvWindowSize() int32 {
-	if s.MaxUploadBufferPerStream > 0 {
-		return s.MaxUploadBufferPerStream
-	}
-	return 1 << 20
-}
-
-func (s *http2Server) maxReadFrameSize() uint32 {
-	if v := s.MaxReadFrameSize; v >= http2minMaxFrameSize && v <= http2maxFrameSize {
-		return v
-	}
-	return http2defaultMaxReadFrameSize
-}
-
-func (s *http2Server) maxConcurrentStreams() uint32 {
-	if v := s.MaxConcurrentStreams; v > 0 {
-		return v
-	}
-	return http2defaultMaxStreams
-}
-
-// maxQueuedControlFrames is the maximum number of control frames like
-// SETTINGS, PING and RST_STREAM that will be queued for writing before
-// the connection is closed to prevent memory exhaustion attacks.
-func (s *http2Server) maxQueuedControlFrames() int {
-	// TODO: if anybody asks, add a Server field, and remember to define the
-	// behavior of negative values.
-	return http2maxQueuedControlFrames
-}
-
-type http2serverInternalState struct {
-	mu          sync.Mutex
-	activeConns map[*http2serverConn]struct{}
-}
-
-func (s *http2serverInternalState) registerConn(sc *http2serverConn) {
-	if s == nil {
-		return // if the Server was used without calling ConfigureServer
-	}
-	s.mu.Lock()
-	s.activeConns[sc] = struct{}{}
-	s.mu.Unlock()
-}
-
-func (s *http2serverInternalState) unregisterConn(sc *http2serverConn) {
-	if s == nil {
-		return // if the Server was used without calling ConfigureServer
-	}
-	s.mu.Lock()
-	delete(s.activeConns, sc)
-	s.mu.Unlock()
-}
-
-func (s *http2serverInternalState) startGracefulShutdown() {
-	if s == nil {
-		return // if the Server was used without calling ConfigureServer
-	}
-	s.mu.Lock()
-	for sc := range s.activeConns {
-		sc.startGracefulShutdown()
-	}
-	s.mu.Unlock()
-}
-
-// ConfigureServer adds HTTP/2 support to a net/http Server.
-//
-// The configuration conf may be nil.
-//
-// ConfigureServer must be called before s begins serving.
-func http2ConfigureServer(s *Server, conf *http2Server) error {
-	if s == nil {
-		panic("nil *http.Server")
-	}
-	if conf == nil {
-		conf = new(http2Server)
-	}
-	conf.state = &http2serverInternalState{activeConns: make(map[*http2serverConn]struct{})}
-	if h1, h2 := s, conf; h2.IdleTimeout == 0 {
-		if h1.IdleTimeout != 0 {
-			h2.IdleTimeout = h1.IdleTimeout
-		} else {
-			h2.IdleTimeout = h1.ReadTimeout
-		}
-	}
-	s.RegisterOnShutdown(conf.state.startGracefulShutdown)
-
-	if s.TLSConfig == nil {
-		s.TLSConfig = new(tls.Config)
-	} else if s.TLSConfig.CipherSuites != nil && s.TLSConfig.MinVersion < tls.VersionTLS13 {
-		// If they already provided a TLS 1.0–1.2 CipherSuite list, return an
-		// error if it is missing ECDHE_RSA_WITH_AES_128_GCM_SHA256 or
-		// ECDHE_ECDSA_WITH_AES_128_GCM_SHA256.
-		haveRequired := false
-		for _, cs := range s.TLSConfig.CipherSuites {
-			switch cs {
-			case tls.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
-				// Alternative MTI cipher to not discourage ECDSA-only servers.
-				// See http://golang.org/cl/30721 for further information.
-				tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256:
-				haveRequired = true
-			}
-		}
-		if !haveRequired {
-			return fmt.Errorf("http2: TLSConfig.CipherSuites is missing an HTTP/2-required AES_128_GCM_SHA256 cipher (need at least one of TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 or TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256)")
-		}
-	}
-
-	// Note: not setting MinVersion to tls.VersionTLS12,
-	// as we don't want to interfere with HTTP/1.1 traffic
-	// on the user's server. We enforce TLS 1.2 later once
-	// we accept a connection. Ideally this should be done
-	// during next-proto selection, but using TLS <1.2 with
-	// HTTP/2 is still the client's bug.
-
-	s.TLSConfig.PreferServerCipherSuites = true
-
-	if !http2strSliceContains(s.TLSConfig.NextProtos, http2NextProtoTLS) {
-		s.TLSConfig.NextProtos = append(s.TLSConfig.NextProtos, http2NextProtoTLS)
-	}
-	if !http2strSliceContains(s.TLSConfig.NextProtos, "http/1.1") {
-		s.TLSConfig.NextProtos = append(s.TLSConfig.NextProtos, "http/1.1")
-	}
-
-	if s.TLSNextProto == nil {
-		s.TLSNextProto = map[string]func(*Server, *tls.Conn, Handler){}
-	}
-	protoHandler := func(hs *Server, c *tls.Conn, h Handler) {
-		if http2testHookOnConn != nil {
-			http2testHookOnConn()
-		}
-		// The TLSNextProto interface predates contexts, so
-		// the net/http package passes down its per-connection
-		// base context via an exported but unadvertised
-		// method on the Handler. This is for internal
-		// net/http<=>http2 use only.
-		var ctx context.Context
-		type baseContexter interface {
-			BaseContext() context.Context
-		}
-		if bc, ok := h.(baseContexter); ok {
-			ctx = bc.BaseContext()
-		}
-		conf.ServeConn(c, &http2ServeConnOpts{
-			Context:    ctx,
-			Handler:    h,
-			BaseConfig: hs,
-		})
-	}
-	s.TLSNextProto[http2NextProtoTLS] = protoHandler
-	return nil
-}
-
-// ServeConnOpts are options for the Server.ServeConn method.
-type http2ServeConnOpts struct {
-	// Context is the base context to use.
-	// If nil, context.Background is used.
-	Context context.Context
-
-	// BaseConfig optionally sets the base configuration
-	// for values. If nil, defaults are used.
-	BaseConfig *Server
-
-	// Handler specifies which handler to use for processing
-	// requests. If nil, BaseConfig.Handler is used. If BaseConfig
-	// or BaseConfig.Handler is nil, http.DefaultServeMux is used.
-	Handler Handler
-}
-
-func (o *http2ServeConnOpts) context() context.Context {
-	if o != nil && o.Context != nil {
-		return o.Context
-	}
-	return context.Background()
-}
-
-func (o *http2ServeConnOpts) baseConfig() *Server {
-	if o != nil && o.BaseConfig != nil {
-		return o.BaseConfig
-	}
-	return new(Server)
-}
-
-func (o *http2ServeConnOpts) handler() Handler {
-	if o != nil {
-		if o.Handler != nil {
-			return o.Handler
-		}
-		if o.BaseConfig != nil && o.BaseConfig.Handler != nil {
-			return o.BaseConfig.Handler
-		}
-	}
-	return DefaultServeMux
-}
-
-// ServeConn serves HTTP/2 requests on the provided connection and
-// blocks until the connection is no longer readable.
-//
-// ServeConn starts speaking HTTP/2 assuming that c has not had any
-// reads or writes. It writes its initial settings frame and expects
-// to be able to read the preface and settings frame from the
-// client. If c has a ConnectionState method like a *tls.Conn, the
-// ConnectionState is used to verify the TLS ciphersuite and to set
-// the Request.TLS field in Handlers.
-//
-// ServeConn does not support h2c by itself. Any h2c support must be
-// implemented in terms of providing a suitably-behaving net.Conn.
-//
-// The opts parameter is optional. If nil, default values are used.
-func (s *http2Server) ServeConn(c net.Conn, opts *http2ServeConnOpts) {
-	baseCtx, cancel := http2serverConnBaseContext(c, opts)
-	defer cancel()
-
-	sc := &http2serverConn{
-		srv:                         s,
-		hs:                          opts.baseConfig(),
-		conn:                        c,
-		baseCtx:                     baseCtx,
-		remoteAddrStr:               c.RemoteAddr().String(),
-		bw:                          http2newBufferedWriter(c),
-		handler:                     opts.handler(),
-		streams:                     make(map[uint32]*http2stream),
-		readFrameCh:                 make(chan http2readFrameResult),
-		wantWriteFrameCh:            make(chan http2FrameWriteRequest, 8),
-		serveMsgCh:                  make(chan interface{}, 8),
-		wroteFrameCh:                make(chan http2frameWriteResult, 1), // buffered; one send in writeFrameAsync
-		bodyReadCh:                  make(chan http2bodyReadMsg),         // buffering doesn't matter either way
-		doneServing:                 make(chan struct{}),
-		clientMaxStreams:            math.MaxUint32, // Section 6.5.2: "Initially, there is no limit to this value"
-		advMaxStreams:               s.maxConcurrentStreams(),
-		initialStreamSendWindowSize: http2initialWindowSize,
-		maxFrameSize:                http2initialMaxFrameSize,
-		headerTableSize:             http2initialHeaderTableSize,
-		serveG:                      http2newGoroutineLock(),
-		pushEnabled:                 true,
-	}
-
-	s.state.registerConn(sc)
-	defer s.state.unregisterConn(sc)
-
-	// The net/http package sets the write deadline from the
-	// http.Server.WriteTimeout during the TLS handshake, but then
-	// passes the connection off to us with the deadline already set.
-	// Write deadlines are set per stream in serverConn.newStream.
-	// Disarm the net.Conn write deadline here.
-	if sc.hs.WriteTimeout != 0 {
-		sc.conn.SetWriteDeadline(time.Time{})
-	}
-
-	if s.NewWriteScheduler != nil {
-		sc.writeSched = s.NewWriteScheduler()
-	} else {
-		sc.writeSched = http2NewRandomWriteScheduler()
-	}
-
-	// These start at the RFC-specified defaults. If there is a higher
-	// configured value for inflow, that will be updated when we send a
-	// WINDOW_UPDATE shortly after sending SETTINGS.
-	sc.flow.add(http2initialWindowSize)
-	sc.inflow.add(http2initialWindowSize)
-	sc.hpackEncoder = hpack.NewEncoder(&sc.headerWriteBuf)
-
-	fr := http2NewFramer(sc.bw, c)
-	if s.CountError != nil {
-		fr.countError = s.CountError
-	}
-	fr.ReadMetaHeaders = hpack.NewDecoder(http2initialHeaderTableSize, nil)
-	fr.MaxHeaderListSize = sc.maxHeaderListSize()
-	fr.SetMaxReadFrameSize(s.maxReadFrameSize())
-	sc.framer = fr
-
-	if tc, ok := c.(http2connectionStater); ok {
-		sc.tlsState = new(tls.ConnectionState)
-		*sc.tlsState = tc.ConnectionState()
-		// 9.2 Use of TLS Features
-		// An implementation of HTTP/2 over TLS MUST use TLS
-		// 1.2 or higher with the restrictions on feature set
-		// and cipher suite described in this section. Due to
-		// implementation limitations, it might not be
-		// possible to fail TLS negotiation. An endpoint MUST
-		// immediately terminate an HTTP/2 connection that
-		// does not meet the TLS requirements described in
-		// this section with a connection error (Section
-		// 5.4.1) of type INADEQUATE_SECURITY.
-		if sc.tlsState.Version < tls.VersionTLS12 {
-			sc.rejectConn(http2ErrCodeInadequateSecurity, "TLS version too low")
-			return
-		}
-
-		if sc.tlsState.ServerName == "" {
-			// Client must use SNI, but we don't enforce that anymore,
-			// since it was causing problems when connecting to bare IP
-			// addresses during development.
-			//
-			// TODO: optionally enforce? Or enforce at the time we receive
-			// a new request, and verify the ServerName matches the :authority?
-			// But that precludes proxy situations, perhaps.
-			//
-			// So for now, do nothing here again.
-		}
-
-		if !s.PermitProhibitedCipherSuites && http2isBadCipher(sc.tlsState.CipherSuite) {
-			// "Endpoints MAY choose to generate a connection error
-			// (Section 5.4.1) of type INADEQUATE_SECURITY if one of
-			// the prohibited cipher suites are negotiated."
-			//
-			// We choose that. In my opinion, the spec is weak
-			// here. It also says both parties must support at least
-			// TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 so there's no
-			// excuses here. If we really must, we could allow an
-			// "AllowInsecureWeakCiphers" option on the server later.
-			// Let's see how it plays out first.
-			sc.rejectConn(http2ErrCodeInadequateSecurity, fmt.Sprintf("Prohibited TLS 1.2 Cipher Suite: %x", sc.tlsState.CipherSuite))
-			return
-		}
-	}
-
-	if hook := http2testHookGetServerConn; hook != nil {
-		hook(sc)
-	}
-	sc.serve()
-}
-
-func http2serverConnBaseContext(c net.Conn, opts *http2ServeConnOpts) (ctx context.Context, cancel func()) {
-	ctx, cancel = context.WithCancel(opts.context())
-	ctx = context.WithValue(ctx, LocalAddrContextKey, c.LocalAddr())
-	if hs := opts.baseConfig(); hs != nil {
-		ctx = context.WithValue(ctx, ServerContextKey, hs)
-	}
-	return
-}
-
-func (sc *http2serverConn) rejectConn(err http2ErrCode, debug string) {
-	sc.vlogf("http2: server rejecting conn: %v, %s", err, debug)
-	// ignoring errors. hanging up anyway.
-	sc.framer.WriteGoAway(0, err, []byte(debug))
-	sc.bw.Flush()
-	sc.conn.Close()
-}
-
-type http2serverConn struct {
-	// Immutable:
-	srv              *http2Server
-	hs               *Server
-	conn             net.Conn
-	bw               *http2bufferedWriter // writing to conn
-	handler          Handler
-	baseCtx          context.Context
-	framer           *http2Framer
-	doneServing      chan struct{}               // closed when serverConn.serve ends
-	readFrameCh      chan http2readFrameResult   // written by serverConn.readFrames
-	wantWriteFrameCh chan http2FrameWriteRequest // from handlers -> serve
-	wroteFrameCh     chan http2frameWriteResult  // from writeFrameAsync -> serve, tickles more frame writes
-	bodyReadCh       chan http2bodyReadMsg       // from handlers -> serve
-	serveMsgCh       chan interface{}            // misc messages & code to send to / run on the serve loop
-	flow             http2flow                   // conn-wide (not stream-specific) outbound flow control
-	inflow           http2flow                   // conn-wide inbound flow control
-	tlsState         *tls.ConnectionState        // shared by all handlers, like net/http
-	remoteAddrStr    string
-	writeSched       http2WriteScheduler
-
-	// Everything following is owned by the serve loop; use serveG.check():
-	serveG                      http2goroutineLock // used to verify funcs are on serve()
-	pushEnabled                 bool
-	sawFirstSettings            bool // got the initial SETTINGS frame after the preface
-	needToSendSettingsAck       bool
-	unackedSettings             int    // how many SETTINGS have we sent without ACKs?
-	queuedControlFrames         int    // control frames in the writeSched queue
-	clientMaxStreams            uint32 // SETTINGS_MAX_CONCURRENT_STREAMS from client (our PUSH_PROMISE limit)
-	advMaxStreams               uint32 // our SETTINGS_MAX_CONCURRENT_STREAMS advertised the client
-	curClientStreams            uint32 // number of open streams initiated by the client
-	curPushedStreams            uint32 // number of open streams initiated by server push
-	maxClientStreamID           uint32 // max ever seen from client (odd), or 0 if there have been no client requests
-	maxPushPromiseID            uint32 // ID of the last push promise (even), or 0 if there have been no pushes
-	streams                     map[uint32]*http2stream
-	initialStreamSendWindowSize int32
-	maxFrameSize                int32
-	headerTableSize             uint32
-	peerMaxHeaderListSize       uint32            // zero means unknown (default)
-	canonHeader                 map[string]string // http2-lower-case -> Go-Canonical-Case
-	writingFrame                bool              // started writing a frame (on serve goroutine or separate)
-	writingFrameAsync           bool              // started a frame on its own goroutine but haven't heard back on wroteFrameCh
-	needsFrameFlush             bool              // last frame write wasn't a flush
-	inGoAway                    bool              // we've started to or sent GOAWAY
-	inFrameScheduleLoop         bool              // whether we're in the scheduleFrameWrite loop
-	needToSendGoAway            bool              // we need to schedule a GOAWAY frame write
-	goAwayCode                  http2ErrCode
-	shutdownTimer               *time.Timer // nil until used
-	idleTimer                   *time.Timer // nil if unused
-
-	// Owned by the writeFrameAsync goroutine:
-	headerWriteBuf bytes.Buffer
-	hpackEncoder   *hpack.Encoder
-
-	// Used by startGracefulShutdown.
-	shutdownOnce sync.Once
-}
-
-func (sc *http2serverConn) maxHeaderListSize() uint32 {
-	n := sc.hs.MaxHeaderBytes
-	if n <= 0 {
-		n = DefaultMaxHeaderBytes
-	}
-	// http2's count is in a slightly different unit and includes 32 bytes per pair.
-	// So, take the net/http.Server value and pad it up a bit, assuming 10 headers.
-	const perFieldOverhead = 32 // per http2 spec
-	const typicalHeaders = 10   // conservative
-	return uint32(n + typicalHeaders*perFieldOverhead)
-}
-
-func (sc *http2serverConn) curOpenStreams() uint32 {
-	sc.serveG.check()
-	return sc.curClientStreams + sc.curPushedStreams
-}
-
-// stream represents a stream. This is the minimal metadata needed by
-// the serve goroutine. Most of the actual stream state is owned by
-// the http.Handler's goroutine in the responseWriter. Because the
-// responseWriter's responseWriterState is recycled at the end of a
-// handler, this struct intentionally has no pointer to the
-// *responseWriter{,State} itself, as the Handler ending nils out the
-// responseWriter's state field.
-type http2stream struct {
-	// immutable:
-	sc        *http2serverConn
-	id        uint32
-	body      *http2pipe       // non-nil if expecting DATA frames
-	cw        http2closeWaiter // closed wait stream transitions to closed state
-	ctx       context.Context
-	cancelCtx func()
-
-	// owned by serverConn's serve loop:
-	bodyBytes        int64     // body bytes seen so far
-	declBodyBytes    int64     // or -1 if undeclared
-	flow             http2flow // limits writing from Handler to client
-	inflow           http2flow // what the client is allowed to POST/etc to us
-	state            http2streamState
-	resetQueued      bool        // RST_STREAM queued for write; set by sc.resetStream
-	gotTrailerHeader bool        // HEADER frame for trailers was seen
-	wroteHeaders     bool        // whether we wrote headers (not status 100)
-	writeDeadline    *time.Timer // nil if unused
-
-	trailer    Header // accumulated trailers
-	reqTrailer Header // handler's Request.Trailer
-}
-
-func (sc *http2serverConn) Framer() *http2Framer { return sc.framer }
-
-func (sc *http2serverConn) CloseConn() error { return sc.conn.Close() }
-
-func (sc *http2serverConn) Flush() error { return sc.bw.Flush() }
-
-func (sc *http2serverConn) HeaderEncoder() (*hpack.Encoder, *bytes.Buffer) {
-	return sc.hpackEncoder, &sc.headerWriteBuf
-}
-
-func (sc *http2serverConn) state(streamID uint32) (http2streamState, *http2stream) {
-	sc.serveG.check()
-	// http://tools.ietf.org/html/rfc7540#section-5.1
-	if st, ok := sc.streams[streamID]; ok {
-		return st.state, st
-	}
-	// "The first use of a new stream identifier implicitly closes all
-	// streams in the "idle" state that might have been initiated by
-	// that peer with a lower-valued stream identifier. For example, if
-	// a client sends a HEADERS frame on stream 7 without ever sending a
-	// frame on stream 5, then stream 5 transitions to the "closed"
-	// state when the first frame for stream 7 is sent or received."
-	if streamID%2 == 1 {
-		if streamID <= sc.maxClientStreamID {
-			return http2stateClosed, nil
-		}
-	} else {
-		if streamID <= sc.maxPushPromiseID {
-			return http2stateClosed, nil
-		}
-	}
-	return http2stateIdle, nil
-}
-
-// setConnState calls the net/http ConnState hook for this connection, if configured.
-// Note that the net/http package does StateNew and StateClosed for us.
-// There is currently no plan for StateHijacked or hijacking HTTP/2 connections.
-func (sc *http2serverConn) setConnState(state ConnState) {
-	if sc.hs.ConnState != nil {
-		sc.hs.ConnState(sc.conn, state)
-	}
-}
-
-func (sc *http2serverConn) vlogf(format string, args ...interface{}) {
-	if http2VerboseLogs {
-		sc.logf(format, args...)
-	}
-}
-
-func (sc *http2serverConn) logf(format string, args ...interface{}) {
-	if lg := sc.hs.ErrorLog; lg != nil {
-		lg.Printf(format, args...)
-	} else {
-		log.Printf(format, args...)
-	}
-}
-
-// errno returns v's underlying uintptr, else 0.
-//
-// TODO: remove this helper function once http2 can use build
-// tags. See comment in isClosedConnError.
-func http2errno(v error) uintptr {
-	if rv := reflect.ValueOf(v); rv.Kind() == reflect.Uintptr {
-		return uintptr(rv.Uint())
-	}
-	return 0
-}
-
-// isClosedConnError reports whether err is an error from use of a closed
-// network connection.
-func http2isClosedConnError(err error) bool {
-	if err == nil {
-		return false
-	}
-
-	// TODO: remove this string search and be more like the Windows
-	// case below. That might involve modifying the standard library
-	// to return better error types.
-	str := err.Error()
-	if strings.Contains(str, "use of closed network connection") {
-		return true
-	}
-
-	// TODO(bradfitz): x/tools/cmd/bundle doesn't really support
-	// build tags, so I can't make an http2_windows.go file with
-	// Windows-specific stuff. Fix that and move this, once we
-	// have a way to bundle this into std's net/http somehow.
-	if runtime.GOOS == "windows" {
-		if oe, ok := err.(*net.OpError); ok && oe.Op == "read" {
-			if se, ok := oe.Err.(*os.SyscallError); ok && se.Syscall == "wsarecv" {
-				const WSAECONNABORTED = 10053
-				const WSAECONNRESET = 10054
-				if n := http2errno(se.Err); n == WSAECONNRESET || n == WSAECONNABORTED {
-					return true
-				}
-			}
-		}
-	}
-	return false
-}
-
-func (sc *http2serverConn) condlogf(err error, format string, args ...interface{}) {
-	if err == nil {
-		return
-	}
-	if err == io.EOF || err == io.ErrUnexpectedEOF || http2isClosedConnError(err) || err == http2errPrefaceTimeout {
-		// Boring, expected errors.
-		sc.vlogf(format, args...)
-	} else {
-		sc.logf(format, args...)
-	}
-}
-
-func (sc *http2serverConn) canonicalHeader(v string) string {
-	sc.serveG.check()
-	http2buildCommonHeaderMapsOnce()
-	cv, ok := http2commonCanonHeader[v]
-	if ok {
-		return cv
-	}
-	cv, ok = sc.canonHeader[v]
-	if ok {
-		return cv
-	}
-	if sc.canonHeader == nil {
-		sc.canonHeader = make(map[string]string)
-	}
-	cv = CanonicalHeaderKey(v)
-	// maxCachedCanonicalHeaders is an arbitrarily-chosen limit on the number of
-	// entries in the canonHeader cache. This should be larger than the number
-	// of unique, uncommon header keys likely to be sent by the peer, while not
-	// so high as to permit unreaasonable memory usage if the peer sends an unbounded
-	// number of unique header keys.
-	const maxCachedCanonicalHeaders = 32
-	if len(sc.canonHeader) < maxCachedCanonicalHeaders {
-		sc.canonHeader[v] = cv
-	}
-	return cv
-}
-
-type http2readFrameResult struct {
-	f   http2Frame // valid until readMore is called
-	err error
-
-	// readMore should be called once the consumer no longer needs or
-	// retains f. After readMore, f is invalid and more frames can be
-	// read.
-	readMore func()
-}
-
-// readFrames is the loop that reads incoming frames.
-// It takes care to only read one frame at a time, blocking until the
-// consumer is done with the frame.
-// It's run on its own goroutine.
-func (sc *http2serverConn) readFrames() {
-	gate := make(http2gate)
-	gateDone := gate.Done
-	for {
-		f, err := sc.framer.ReadFrame()
-		select {
-		case sc.readFrameCh <- http2readFrameResult{f, err, gateDone}:
-		case <-sc.doneServing:
-			return
-		}
-		select {
-		case <-gate:
-		case <-sc.doneServing:
-			return
-		}
-		if http2terminalReadFrameError(err) {
-			return
-		}
-	}
-}
-
-// frameWriteResult is the message passed from writeFrameAsync to the serve goroutine.
-type http2frameWriteResult struct {
-	_   http2incomparable
-	wr  http2FrameWriteRequest // what was written (or attempted)
-	err error                  // result of the writeFrame call
-}
-
-// writeFrameAsync runs in its own goroutine and writes a single frame
-// and then reports when it's done.
-// At most one goroutine can be running writeFrameAsync at a time per
-// serverConn.
-func (sc *http2serverConn) writeFrameAsync(wr http2FrameWriteRequest) {
-	err := wr.write.writeFrame(sc)
-	sc.wroteFrameCh <- http2frameWriteResult{wr: wr, err: err}
-}
-
-func (sc *http2serverConn) closeAllStreamsOnConnClose() {
-	sc.serveG.check()
-	for _, st := range sc.streams {
-		sc.closeStream(st, http2errClientDisconnected)
-	}
-}
-
-func (sc *http2serverConn) stopShutdownTimer() {
-	sc.serveG.check()
-	if t := sc.shutdownTimer; t != nil {
-		t.Stop()
-	}
-}
-
-func (sc *http2serverConn) notePanic() {
-	// Note: this is for serverConn.serve panicking, not http.Handler code.
-	if http2testHookOnPanicMu != nil {
-		http2testHookOnPanicMu.Lock()
-		defer http2testHookOnPanicMu.Unlock()
-	}
-	if http2testHookOnPanic != nil {
-		if e := recover(); e != nil {
-			if http2testHookOnPanic(sc, e) {
-				panic(e)
-			}
-		}
-	}
-}
-
-func (sc *http2serverConn) serve() {
-	sc.serveG.check()
-	defer sc.notePanic()
-	defer sc.conn.Close()
-	defer sc.closeAllStreamsOnConnClose()
-	defer sc.stopShutdownTimer()
-	defer close(sc.doneServing) // unblocks handlers trying to send
-
-	if http2VerboseLogs {
-		sc.vlogf("http2: server connection from %v on %p", sc.conn.RemoteAddr(), sc.hs)
-	}
-
-	sc.writeFrame(http2FrameWriteRequest{
-		write: http2writeSettings{
-			{http2SettingMaxFrameSize, sc.srv.maxReadFrameSize()},
-			{http2SettingMaxConcurrentStreams, sc.advMaxStreams},
-			{http2SettingMaxHeaderListSize, sc.maxHeaderListSize()},
-			{http2SettingInitialWindowSize, uint32(sc.srv.initialStreamRecvWindowSize())},
-		},
-	})
-	sc.unackedSettings++
-
-	// Each connection starts with initialWindowSize inflow tokens.
-	// If a higher value is configured, we add more tokens.
-	if diff := sc.srv.initialConnRecvWindowSize() - http2initialWindowSize; diff > 0 {
-		sc.sendWindowUpdate(nil, int(diff))
-	}
-
-	if err := sc.readPreface(); err != nil {
-		sc.condlogf(err, "http2: server: error reading preface from client %v: %v", sc.conn.RemoteAddr(), err)
-		return
-	}
-	// Now that we've got the preface, get us out of the
-	// "StateNew" state. We can't go directly to idle, though.
-	// Active means we read some data and anticipate a request. We'll
-	// do another Active when we get a HEADERS frame.
-	sc.setConnState(StateActive)
-	sc.setConnState(StateIdle)
-
-	if sc.srv.IdleTimeout != 0 {
-		sc.idleTimer = time.AfterFunc(sc.srv.IdleTimeout, sc.onIdleTimer)
-		defer sc.idleTimer.Stop()
-	}
-
-	go sc.readFrames() // closed by defer sc.conn.Close above
-
-	settingsTimer := time.AfterFunc(http2firstSettingsTimeout, sc.onSettingsTimer)
-	defer settingsTimer.Stop()
-
-	loopNum := 0
-	for {
-		loopNum++
-		select {
-		case wr := <-sc.wantWriteFrameCh:
-			if se, ok := wr.write.(http2StreamError); ok {
-				sc.resetStream(se)
-				break
-			}
-			sc.writeFrame(wr)
-		case res := <-sc.wroteFrameCh:
-			sc.wroteFrame(res)
-		case res := <-sc.readFrameCh:
-			// Process any written frames before reading new frames from the client since a
-			// written frame could have triggered a new stream to be started.
-			if sc.writingFrameAsync {
-				select {
-				case wroteRes := <-sc.wroteFrameCh:
-					sc.wroteFrame(wroteRes)
-				default:
-				}
-			}
-			if !sc.processFrameFromReader(res) {
-				return
-			}
-			res.readMore()
-			if settingsTimer != nil {
-				settingsTimer.Stop()
-				settingsTimer = nil
-			}
-		case m := <-sc.bodyReadCh:
-			sc.noteBodyRead(m.st, m.n)
-		case msg := <-sc.serveMsgCh:
-			switch v := msg.(type) {
-			case func(int):
-				v(loopNum) // for testing
-			case *http2serverMessage:
-				switch v {
-				case http2settingsTimerMsg:
-					sc.logf("timeout waiting for SETTINGS frames from %v", sc.conn.RemoteAddr())
-					return
-				case http2idleTimerMsg:
-					sc.vlogf("connection is idle")
-					sc.goAway(http2ErrCodeNo)
-				case http2shutdownTimerMsg:
-					sc.vlogf("GOAWAY close timer fired; closing conn from %v", sc.conn.RemoteAddr())
-					return
-				case http2gracefulShutdownMsg:
-					sc.startGracefulShutdownInternal()
-				default:
-					panic("unknown timer")
-				}
-			case *http2startPushRequest:
-				sc.startPush(v)
-			default:
-				panic(fmt.Sprintf("unexpected type %T", v))
-			}
-		}
-
-		// If the peer is causing us to generate a lot of control frames,
-		// but not reading them from us, assume they are trying to make us
-		// run out of memory.
-		if sc.queuedControlFrames > sc.srv.maxQueuedControlFrames() {
-			sc.vlogf("http2: too many control frames in send queue, closing connection")
-			return
-		}
-
-		// Start the shutdown timer after sending a GOAWAY. When sending GOAWAY
-		// with no error code (graceful shutdown), don't start the timer until
-		// all open streams have been completed.
-		sentGoAway := sc.inGoAway && !sc.needToSendGoAway && !sc.writingFrame
-		gracefulShutdownComplete := sc.goAwayCode == http2ErrCodeNo && sc.curOpenStreams() == 0
-		if sentGoAway && sc.shutdownTimer == nil && (sc.goAwayCode != http2ErrCodeNo || gracefulShutdownComplete) {
-			sc.shutDownIn(http2goAwayTimeout)
-		}
-	}
-}
-
-func (sc *http2serverConn) awaitGracefulShutdown(sharedCh <-chan struct{}, privateCh chan struct{}) {
-	select {
-	case <-sc.doneServing:
-	case <-sharedCh:
-		close(privateCh)
-	}
-}
-
-type http2serverMessage int
-
-// Message values sent to serveMsgCh.
-var (
-	http2settingsTimerMsg    = new(http2serverMessage)
-	http2idleTimerMsg        = new(http2serverMessage)
-	http2shutdownTimerMsg    = new(http2serverMessage)
-	http2gracefulShutdownMsg = new(http2serverMessage)
-)
-
-func (sc *http2serverConn) onSettingsTimer() { sc.sendServeMsg(http2settingsTimerMsg) }
-
-func (sc *http2serverConn) onIdleTimer() { sc.sendServeMsg(http2idleTimerMsg) }
-
-func (sc *http2serverConn) onShutdownTimer() { sc.sendServeMsg(http2shutdownTimerMsg) }
-
-func (sc *http2serverConn) sendServeMsg(msg interface{}) {
-	sc.serveG.checkNotOn() // NOT
-	select {
-	case sc.serveMsgCh <- msg:
-	case <-sc.doneServing:
-	}
-}
-
-var http2errPrefaceTimeout = errors.New("timeout waiting for client preface")
-
-// readPreface reads the ClientPreface greeting from the peer or
-// returns errPrefaceTimeout on timeout, or an error if the greeting
-// is invalid.
-func (sc *http2serverConn) readPreface() error {
-	errc := make(chan error, 1)
-	go func() {
-		// Read the client preface
-		buf := make([]byte, len(http2ClientPreface))
-		if _, err := io.ReadFull(sc.conn, buf); err != nil {
-			errc <- err
-		} else if !bytes.Equal(buf, http2clientPreface) {
-			errc <- fmt.Errorf("bogus greeting %q", buf)
-		} else {
-			errc <- nil
-		}
-	}()
-	timer := time.NewTimer(http2prefaceTimeout) // TODO: configurable on *Server?
-	defer timer.Stop()
-	select {
-	case <-timer.C:
-		return http2errPrefaceTimeout
-	case err := <-errc:
-		if err == nil {
-			if http2VerboseLogs {
-				sc.vlogf("http2: server: client %v said hello", sc.conn.RemoteAddr())
-			}
-		}
-		return err
-	}
-}
-
-var http2errChanPool = sync.Pool{
-	New: func() interface{} { return make(chan error, 1) },
-}
-
-var http2writeDataPool = sync.Pool{
-	New: func() interface{} { return new(http2writeData) },
-}
-
-// writeDataFromHandler writes DATA response frames from a handler on
-// the given stream.
-func (sc *http2serverConn) writeDataFromHandler(stream *http2stream, data []byte, endStream bool) error {
-	ch := http2errChanPool.Get().(chan error)
-	writeArg := http2writeDataPool.Get().(*http2writeData)
-	*writeArg = http2writeData{stream.id, data, endStream}
-	err := sc.writeFrameFromHandler(http2FrameWriteRequest{
-		write:  writeArg,
-		stream: stream,
-		done:   ch,
-	})
-	if err != nil {
-		return err
-	}
-	var frameWriteDone bool // the frame write is done (successfully or not)
-	select {
-	case err = <-ch:
-		frameWriteDone = true
-	case <-sc.doneServing:
-		return http2errClientDisconnected
-	case <-stream.cw:
-		// If both ch and stream.cw were ready (as might
-		// happen on the final Write after an http.Handler
-		// ends), prefer the write result. Otherwise this
-		// might just be us successfully closing the stream.
-		// The writeFrameAsync and serve goroutines guarantee
-		// that the ch send will happen before the stream.cw
-		// close.
-		select {
-		case err = <-ch:
-			frameWriteDone = true
-		default:
-			return http2errStreamClosed
-		}
-	}
-	http2errChanPool.Put(ch)
-	if frameWriteDone {
-		http2writeDataPool.Put(writeArg)
-	}
-	return err
-}
-
-// writeFrameFromHandler sends wr to sc.wantWriteFrameCh, but aborts
-// if the connection has gone away.
-//
-// This must not be run from the serve goroutine itself, else it might
-// deadlock writing to sc.wantWriteFrameCh (which is only mildly
-// buffered and is read by serve itself). If you're on the serve
-// goroutine, call writeFrame instead.
-func (sc *http2serverConn) writeFrameFromHandler(wr http2FrameWriteRequest) error {
-	sc.serveG.checkNotOn() // NOT
-	select {
-	case sc.wantWriteFrameCh <- wr:
-		return nil
-	case <-sc.doneServing:
-		// Serve loop is gone.
-		// Client has closed their connection to the server.
-		return http2errClientDisconnected
-	}
-}
-
-// writeFrame schedules a frame to write and sends it if there's nothing
-// already being written.
-//
-// There is no pushback here (the serve goroutine never blocks). It's
-// the http.Handlers that block, waiting for their previous frames to
-// make it onto the wire
-//
-// If you're not on the serve goroutine, use writeFrameFromHandler instead.
-func (sc *http2serverConn) writeFrame(wr http2FrameWriteRequest) {
-	sc.serveG.check()
-
-	// If true, wr will not be written and wr.done will not be signaled.
-	var ignoreWrite bool
-
-	// We are not allowed to write frames on closed streams. RFC 7540 Section
-	// 5.1.1 says: "An endpoint MUST NOT send frames other than PRIORITY on
-	// a closed stream." Our server never sends PRIORITY, so that exception
-	// does not apply.
-	//
-	// The serverConn might close an open stream while the stream's handler
-	// is still running. For example, the server might close a stream when it
-	// receives bad data from the client. If this happens, the handler might
-	// attempt to write a frame after the stream has been closed (since the
-	// handler hasn't yet been notified of the close). In this case, we simply
-	// ignore the frame. The handler will notice that the stream is closed when
-	// it waits for the frame to be written.
-	//
-	// As an exception to this rule, we allow sending RST_STREAM after close.
-	// This allows us to immediately reject new streams without tracking any
-	// state for those streams (except for the queued RST_STREAM frame). This
-	// may result in duplicate RST_STREAMs in some cases, but the client should
-	// ignore those.
-	if wr.StreamID() != 0 {
-		_, isReset := wr.write.(http2StreamError)
-		if state, _ := sc.state(wr.StreamID()); state == http2stateClosed && !isReset {
-			ignoreWrite = true
-		}
-	}
-
-	// Don't send a 100-continue response if we've already sent headers.
-	// See golang.org/issue/14030.
-	switch wr.write.(type) {
-	case *http2writeResHeaders:
-		wr.stream.wroteHeaders = true
-	case http2write100ContinueHeadersFrame:
-		if wr.stream.wroteHeaders {
-			// We do not need to notify wr.done because this frame is
-			// never written with wr.done != nil.
-			if wr.done != nil {
-				panic("wr.done != nil for write100ContinueHeadersFrame")
-			}
-			ignoreWrite = true
-		}
-	}
-
-	if !ignoreWrite {
-		if wr.isControl() {
-			sc.queuedControlFrames++
-			// For extra safety, detect wraparounds, which should not happen,
-			// and pull the plug.
-			if sc.queuedControlFrames < 0 {
-				sc.conn.Close()
-			}
-		}
-		sc.writeSched.Push(wr)
-	}
-	sc.scheduleFrameWrite()
-}
-
-// startFrameWrite starts a goroutine to write wr (in a separate
-// goroutine since that might block on the network), and updates the
-// serve goroutine's state about the world, updated from info in wr.
-func (sc *http2serverConn) startFrameWrite(wr http2FrameWriteRequest) {
-	sc.serveG.check()
-	if sc.writingFrame {
-		panic("internal error: can only be writing one frame at a time")
-	}
-
-	st := wr.stream
-	if st != nil {
-		switch st.state {
-		case http2stateHalfClosedLocal:
-			switch wr.write.(type) {
-			case http2StreamError, http2handlerPanicRST, http2writeWindowUpdate:
-				// RFC 7540 Section 5.1 allows sending RST_STREAM, PRIORITY, and WINDOW_UPDATE
-				// in this state. (We never send PRIORITY from the server, so that is not checked.)
-			default:
-				panic(fmt.Sprintf("internal error: attempt to send frame on a half-closed-local stream: %v", wr))
-			}
-		case http2stateClosed:
-			panic(fmt.Sprintf("internal error: attempt to send frame on a closed stream: %v", wr))
-		}
-	}
-	if wpp, ok := wr.write.(*http2writePushPromise); ok {
-		var err error
-		wpp.promisedID, err = wpp.allocatePromisedID()
-		if err != nil {
-			sc.writingFrameAsync = false
-			wr.replyToWriter(err)
-			return
-		}
-	}
-
-	sc.writingFrame = true
-	sc.needsFrameFlush = true
-	if wr.write.staysWithinBuffer(sc.bw.Available()) {
-		sc.writingFrameAsync = false
-		err := wr.write.writeFrame(sc)
-		sc.wroteFrame(http2frameWriteResult{wr: wr, err: err})
-	} else {
-		sc.writingFrameAsync = true
-		go sc.writeFrameAsync(wr)
-	}
-}
-
-// errHandlerPanicked is the error given to any callers blocked in a read from
-// Request.Body when the main goroutine panics. Since most handlers read in the
-// main ServeHTTP goroutine, this will show up rarely.
-var http2errHandlerPanicked = errors.New("http2: handler panicked")
-
-// wroteFrame is called on the serve goroutine with the result of
-// whatever happened on writeFrameAsync.
-func (sc *http2serverConn) wroteFrame(res http2frameWriteResult) {
-	sc.serveG.check()
-	if !sc.writingFrame {
-		panic("internal error: expected to be already writing a frame")
-	}
-	sc.writingFrame = false
-	sc.writingFrameAsync = false
-
-	wr := res.wr
-
-	if http2writeEndsStream(wr.write) {
-		st := wr.stream
-		if st == nil {
-			panic("internal error: expecting non-nil stream")
-		}
-		switch st.state {
-		case http2stateOpen:
-			// Here we would go to stateHalfClosedLocal in
-			// theory, but since our handler is done and
-			// the net/http package provides no mechanism
-			// for closing a ResponseWriter while still
-			// reading data (see possible TODO at top of
-			// this file), we go into closed state here
-			// anyway, after telling the peer we're
-			// hanging up on them. We'll transition to
-			// stateClosed after the RST_STREAM frame is
-			// written.
-			st.state = http2stateHalfClosedLocal
-			// Section 8.1: a server MAY request that the client abort
-			// transmission of a request without error by sending a
-			// RST_STREAM with an error code of NO_ERROR after sending
-			// a complete response.
-			sc.resetStream(http2streamError(st.id, http2ErrCodeNo))
-		case http2stateHalfClosedRemote:
-			sc.closeStream(st, http2errHandlerComplete)
-		}
-	} else {
-		switch v := wr.write.(type) {
-		case http2StreamError:
-			// st may be unknown if the RST_STREAM was generated to reject bad input.
-			if st, ok := sc.streams[v.StreamID]; ok {
-				sc.closeStream(st, v)
-			}
-		case http2handlerPanicRST:
-			sc.closeStream(wr.stream, http2errHandlerPanicked)
-		}
-	}
-
-	// Reply (if requested) to unblock the ServeHTTP goroutine.
-	wr.replyToWriter(res.err)
-
-	sc.scheduleFrameWrite()
-}
-
-// scheduleFrameWrite tickles the frame writing scheduler.
-//
-// If a frame is already being written, nothing happens. This will be called again
-// when the frame is done being written.
-//
-// If a frame isn't being written and we need to send one, the best frame
-// to send is selected by writeSched.
-//
-// If a frame isn't being written and there's nothing else to send, we
-// flush the write buffer.
-func (sc *http2serverConn) scheduleFrameWrite() {
-	sc.serveG.check()
-	if sc.writingFrame || sc.inFrameScheduleLoop {
-		return
-	}
-	sc.inFrameScheduleLoop = true
-	for !sc.writingFrameAsync {
-		if sc.needToSendGoAway {
-			sc.needToSendGoAway = false
-			sc.startFrameWrite(http2FrameWriteRequest{
-				write: &http2writeGoAway{
-					maxStreamID: sc.maxClientStreamID,
-					code:        sc.goAwayCode,
-				},
-			})
-			continue
-		}
-		if sc.needToSendSettingsAck {
-			sc.needToSendSettingsAck = false
-			sc.startFrameWrite(http2FrameWriteRequest{write: http2writeSettingsAck{}})
-			continue
-		}
-		if !sc.inGoAway || sc.goAwayCode == http2ErrCodeNo {
-			if wr, ok := sc.writeSched.Pop(); ok {
-				if wr.isControl() {
-					sc.queuedControlFrames--
-				}
-				sc.startFrameWrite(wr)
-				continue
-			}
-		}
-		if sc.needsFrameFlush {
-			sc.startFrameWrite(http2FrameWriteRequest{write: http2flushFrameWriter{}})
-			sc.needsFrameFlush = false // after startFrameWrite, since it sets this true
-			continue
-		}
-		break
-	}
-	sc.inFrameScheduleLoop = false
-}
-
-// startGracefulShutdown gracefully shuts down a connection. This
-// sends GOAWAY with ErrCodeNo to tell the client we're gracefully
-// shutting down. The connection isn't closed until all current
-// streams are done.
-//
-// startGracefulShutdown returns immediately; it does not wait until
-// the connection has shut down.
-func (sc *http2serverConn) startGracefulShutdown() {
-	sc.serveG.checkNotOn() // NOT
-	sc.shutdownOnce.Do(func() { sc.sendServeMsg(http2gracefulShutdownMsg) })
-}
-
-// After sending GOAWAY with an error code (non-graceful shutdown), the
-// connection will close after goAwayTimeout.
-//
-// If we close the connection immediately after sending GOAWAY, there may
-// be unsent data in our kernel receive buffer, which will cause the kernel
-// to send a TCP RST on close() instead of a FIN. This RST will abort the
-// connection immediately, whether or not the client had received the GOAWAY.
-//
-// Ideally we should delay for at least 1 RTT + epsilon so the client has
-// a chance to read the GOAWAY and stop sending messages. Measuring RTT
-// is hard, so we approximate with 1 second. See golang.org/issue/18701.
-//
-// This is a var so it can be shorter in tests, where all requests uses the
-// loopback interface making the expected RTT very small.
-//
-// TODO: configurable?
-var http2goAwayTimeout = 1 * time.Second
-
-func (sc *http2serverConn) startGracefulShutdownInternal() {
-	sc.goAway(http2ErrCodeNo)
-}
-
-func (sc *http2serverConn) goAway(code http2ErrCode) {
-	sc.serveG.check()
-	if sc.inGoAway {
-		return
-	}
-	sc.inGoAway = true
-	sc.needToSendGoAway = true
-	sc.goAwayCode = code
-	sc.scheduleFrameWrite()
-}
-
-func (sc *http2serverConn) shutDownIn(d time.Duration) {
-	sc.serveG.check()
-	sc.shutdownTimer = time.AfterFunc(d, sc.onShutdownTimer)
-}
-
-func (sc *http2serverConn) resetStream(se http2StreamError) {
-	sc.serveG.check()
-	sc.writeFrame(http2FrameWriteRequest{write: se})
-	if st, ok := sc.streams[se.StreamID]; ok {
-		st.resetQueued = true
-	}
-}
-
-// processFrameFromReader processes the serve loop's read from readFrameCh from the
-// frame-reading goroutine.
-// processFrameFromReader returns whether the connection should be kept open.
-func (sc *http2serverConn) processFrameFromReader(res http2readFrameResult) bool {
-	sc.serveG.check()
-	err := res.err
-	if err != nil {
-		if err == http2ErrFrameTooLarge {
-			sc.goAway(http2ErrCodeFrameSize)
-			return true // goAway will close the loop
-		}
-		clientGone := err == io.EOF || err == io.ErrUnexpectedEOF || http2isClosedConnError(err)
-		if clientGone {
-			// TODO: could we also get into this state if
-			// the peer does a half close
-			// (e.g. CloseWrite) because they're done
-			// sending frames but they're still wanting
-			// our open replies?  Investigate.
-			// TODO: add CloseWrite to crypto/tls.Conn first
-			// so we have a way to test this? I suppose
-			// just for testing we could have a non-TLS mode.
-			return false
-		}
-	} else {
-		f := res.f
-		if http2VerboseLogs {
-			sc.vlogf("http2: server read frame %v", http2summarizeFrame(f))
-		}
-		err = sc.processFrame(f)
-		if err == nil {
-			return true
-		}
-	}
-
-	switch ev := err.(type) {
-	case http2StreamError:
-		sc.resetStream(ev)
-		return true
-	case http2goAwayFlowError:
-		sc.goAway(http2ErrCodeFlowControl)
-		return true
-	case http2ConnectionError:
-		sc.logf("http2: server connection error from %v: %v", sc.conn.RemoteAddr(), ev)
-		sc.goAway(http2ErrCode(ev))
-		return true // goAway will handle shutdown
-	default:
-		if res.err != nil {
-			sc.vlogf("http2: server closing client connection; error reading frame from client %s: %v", sc.conn.RemoteAddr(), err)
-		} else {
-			sc.logf("http2: server closing client connection: %v", err)
-		}
-		return false
-	}
-}
-
-func (sc *http2serverConn) processFrame(f http2Frame) error {
-	sc.serveG.check()
-
-	// First frame received must be SETTINGS.
-	if !sc.sawFirstSettings {
-		if _, ok := f.(*http2SettingsFrame); !ok {
-			return sc.countError("first_settings", http2ConnectionError(http2ErrCodeProtocol))
-		}
-		sc.sawFirstSettings = true
-	}
-
-	switch f := f.(type) {
-	case *http2SettingsFrame:
-		return sc.processSettings(f)
-	case *http2MetaHeadersFrame:
-		return sc.processHeaders(f)
-	case *http2WindowUpdateFrame:
-		return sc.processWindowUpdate(f)
-	case *http2PingFrame:
-		return sc.processPing(f)
-	case *http2DataFrame:
-		return sc.processData(f)
-	case *http2RSTStreamFrame:
-		return sc.processResetStream(f)
-	case *http2PriorityFrame:
-		return sc.processPriority(f)
-	case *http2GoAwayFrame:
-		return sc.processGoAway(f)
-	case *http2PushPromiseFrame:
-		// A client cannot push. Thus, servers MUST treat the receipt of a PUSH_PROMISE
-		// frame as a connection error (Section 5.4.1) of type PROTOCOL_ERROR.
-		return sc.countError("push_promise", http2ConnectionError(http2ErrCodeProtocol))
-	default:
-		sc.vlogf("http2: server ignoring frame: %v", f.Header())
-		return nil
-	}
-}
-
-func (sc *http2serverConn) processPing(f *http2PingFrame) error {
-	sc.serveG.check()
-	if f.IsAck() {
-		// 6.7 PING: " An endpoint MUST NOT respond to PING frames
-		// containing this flag."
-		return nil
-	}
-	if f.StreamID != 0 {
-		// "PING frames are not associated with any individual
-		// stream. If a PING frame is received with a stream
-		// identifier field value other than 0x0, the recipient MUST
-		// respond with a connection error (Section 5.4.1) of type
-		// PROTOCOL_ERROR."
-		return sc.countError("ping_on_stream", http2ConnectionError(http2ErrCodeProtocol))
-	}
-	if sc.inGoAway && sc.goAwayCode != http2ErrCodeNo {
-		return nil
-	}
-	sc.writeFrame(http2FrameWriteRequest{write: http2writePingAck{f}})
-	return nil
-}
-
-func (sc *http2serverConn) processWindowUpdate(f *http2WindowUpdateFrame) error {
-	sc.serveG.check()
-	switch {
-	case f.StreamID != 0: // stream-level flow control
-		state, st := sc.state(f.StreamID)
-		if state == http2stateIdle {
-			// Section 5.1: "Receiving any frame other than HEADERS
-			// or PRIORITY on a stream in this state MUST be
-			// treated as a connection error (Section 5.4.1) of
-			// type PROTOCOL_ERROR."
-			return sc.countError("stream_idle", http2ConnectionError(http2ErrCodeProtocol))
-		}
-		if st == nil {
-			// "WINDOW_UPDATE can be sent by a peer that has sent a
-			// frame bearing the END_STREAM flag. This means that a
-			// receiver could receive a WINDOW_UPDATE frame on a "half
-			// closed (remote)" or "closed" stream. A receiver MUST
-			// NOT treat this as an error, see Section 5.1."
-			return nil
-		}
-		if !st.flow.add(int32(f.Increment)) {
-			return sc.countError("bad_flow", http2streamError(f.StreamID, http2ErrCodeFlowControl))
-		}
-	default: // connection-level flow control
-		if !sc.flow.add(int32(f.Increment)) {
-			return http2goAwayFlowError{}
-		}
-	}
-	sc.scheduleFrameWrite()
-	return nil
-}
-
-func (sc *http2serverConn) processResetStream(f *http2RSTStreamFrame) error {
-	sc.serveG.check()
-
-	state, st := sc.state(f.StreamID)
-	if state == http2stateIdle {
-		// 6.4 "RST_STREAM frames MUST NOT be sent for a
-		// stream in the "idle" state. If a RST_STREAM frame
-		// identifying an idle stream is received, the
-		// recipient MUST treat this as a connection error
-		// (Section 5.4.1) of type PROTOCOL_ERROR.
-		return sc.countError("reset_idle_stream", http2ConnectionError(http2ErrCodeProtocol))
-	}
-	if st != nil {
-		st.cancelCtx()
-		sc.closeStream(st, http2streamError(f.StreamID, f.ErrCode))
-	}
-	return nil
-}
-
-func (sc *http2serverConn) closeStream(st *http2stream, err error) {
-	sc.serveG.check()
-	if st.state == http2stateIdle || st.state == http2stateClosed {
-		panic(fmt.Sprintf("invariant; can't close stream in state %v", st.state))
-	}
-	st.state = http2stateClosed
-	if st.writeDeadline != nil {
-		st.writeDeadline.Stop()
-	}
-	if st.isPushed() {
-		sc.curPushedStreams--
-	} else {
-		sc.curClientStreams--
-	}
-	delete(sc.streams, st.id)
-	if len(sc.streams) == 0 {
-		sc.setConnState(StateIdle)
-		if sc.srv.IdleTimeout != 0 {
-			sc.idleTimer.Reset(sc.srv.IdleTimeout)
-		}
-		if http2h1ServerKeepAlivesDisabled(sc.hs) {
-			sc.startGracefulShutdownInternal()
-		}
-	}
-	if p := st.body; p != nil {
-		// Return any buffered unread bytes worth of conn-level flow control.
-		// See golang.org/issue/16481
-		sc.sendWindowUpdate(nil, p.Len())
-
-		p.CloseWithError(err)
-	}
-	st.cw.Close() // signals Handler's CloseNotifier, unblocks writes, etc
-	sc.writeSched.CloseStream(st.id)
-}
-
-func (sc *http2serverConn) processSettings(f *http2SettingsFrame) error {
-	sc.serveG.check()
-	if f.IsAck() {
-		sc.unackedSettings--
-		if sc.unackedSettings < 0 {
-			// Why is the peer ACKing settings we never sent?
-			// The spec doesn't mention this case, but
-			// hang up on them anyway.
-			return sc.countError("ack_mystery", http2ConnectionError(http2ErrCodeProtocol))
-		}
-		return nil
-	}
-	if f.NumSettings() > 100 || f.HasDuplicates() {
-		// This isn't actually in the spec, but hang up on
-		// suspiciously large settings frames or those with
-		// duplicate entries.
-		return sc.countError("settings_big_or_dups", http2ConnectionError(http2ErrCodeProtocol))
-	}
-	if err := f.ForeachSetting(sc.processSetting); err != nil {
-		return err
-	}
-	// TODO: judging by RFC 7540, Section 6.5.3 each SETTINGS frame should be
-	// acknowledged individually, even if multiple are received before the ACK.
-	sc.needToSendSettingsAck = true
-	sc.scheduleFrameWrite()
-	return nil
-}
-
-func (sc *http2serverConn) processSetting(s http2Setting) error {
-	sc.serveG.check()
-	if err := s.Valid(); err != nil {
-		return err
-	}
-	if http2VerboseLogs {
-		sc.vlogf("http2: server processing setting %v", s)
-	}
-	switch s.ID {
-	case http2SettingHeaderTableSize:
-		sc.headerTableSize = s.Val
-		sc.hpackEncoder.SetMaxDynamicTableSize(s.Val)
-	case http2SettingEnablePush:
-		sc.pushEnabled = s.Val != 0
-	case http2SettingMaxConcurrentStreams:
-		sc.clientMaxStreams = s.Val
-	case http2SettingInitialWindowSize:
-		return sc.processSettingInitialWindowSize(s.Val)
-	case http2SettingMaxFrameSize:
-		sc.maxFrameSize = int32(s.Val) // the maximum valid s.Val is < 2^31
-	case http2SettingMaxHeaderListSize:
-		sc.peerMaxHeaderListSize = s.Val
-	default:
-		// Unknown setting: "An endpoint that receives a SETTINGS
-		// frame with any unknown or unsupported identifier MUST
-		// ignore that setting."
-		if http2VerboseLogs {
-			sc.vlogf("http2: server ignoring unknown setting %v", s)
-		}
-	}
-	return nil
-}
-
-func (sc *http2serverConn) processSettingInitialWindowSize(val uint32) error {
-	sc.serveG.check()
-	// Note: val already validated to be within range by
-	// processSetting's Valid call.
-
-	// "A SETTINGS frame can alter the initial flow control window
-	// size for all current streams. When the value of
-	// SETTINGS_INITIAL_WINDOW_SIZE changes, a receiver MUST
-	// adjust the size of all stream flow control windows that it
-	// maintains by the difference between the new value and the
-	// old value."
-	old := sc.initialStreamSendWindowSize
-	sc.initialStreamSendWindowSize = int32(val)
-	growth := int32(val) - old // may be negative
-	for _, st := range sc.streams {
-		if !st.flow.add(growth) {
-			// 6.9.2 Initial Flow Control Window Size
-			// "An endpoint MUST treat a change to
-			// SETTINGS_INITIAL_WINDOW_SIZE that causes any flow
-			// control window to exceed the maximum size as a
-			// connection error (Section 5.4.1) of type
-			// FLOW_CONTROL_ERROR."
-			return sc.countError("setting_win_size", http2ConnectionError(http2ErrCodeFlowControl))
-		}
-	}
-	return nil
-}
-
-func (sc *http2serverConn) processData(f *http2DataFrame) error {
-	sc.serveG.check()
-	id := f.Header().StreamID
-	if sc.inGoAway && (sc.goAwayCode != http2ErrCodeNo || id > sc.maxClientStreamID) {
-		// Discard all DATA frames if the GOAWAY is due to an
-		// error, or:
-		//
-		// Section 6.8: After sending a GOAWAY frame, the sender
-		// can discard frames for streams initiated by the
-		// receiver with identifiers higher than the identified
-		// last stream.
-		return nil
-	}
-
-	data := f.Data()
-	state, st := sc.state(id)
-	if id == 0 || state == http2stateIdle {
-		// Section 6.1: "DATA frames MUST be associated with a
-		// stream. If a DATA frame is received whose stream
-		// identifier field is 0x0, the recipient MUST respond
-		// with a connection error (Section 5.4.1) of type
-		// PROTOCOL_ERROR."
-		//
-		// Section 5.1: "Receiving any frame other than HEADERS
-		// or PRIORITY on a stream in this state MUST be
-		// treated as a connection error (Section 5.4.1) of
-		// type PROTOCOL_ERROR."
-		return sc.countError("data_on_idle", http2ConnectionError(http2ErrCodeProtocol))
-	}
-
-	// "If a DATA frame is received whose stream is not in "open"
-	// or "half closed (local)" state, the recipient MUST respond
-	// with a stream error (Section 5.4.2) of type STREAM_CLOSED."
-	if st == nil || state != http2stateOpen || st.gotTrailerHeader || st.resetQueued {
-		// This includes sending a RST_STREAM if the stream is
-		// in stateHalfClosedLocal (which currently means that
-		// the http.Handler returned, so it's done reading &
-		// done writing). Try to stop the client from sending
-		// more DATA.
-
-		// But still enforce their connection-level flow control,
-		// and return any flow control bytes since we're not going
-		// to consume them.
-		if sc.inflow.available() < int32(f.Length) {
-			return sc.countError("data_flow", http2streamError(id, http2ErrCodeFlowControl))
-		}
-		// Deduct the flow control from inflow, since we're
-		// going to immediately add it back in
-		// sendWindowUpdate, which also schedules sending the
-		// frames.
-		sc.inflow.take(int32(f.Length))
-		sc.sendWindowUpdate(nil, int(f.Length)) // conn-level
-
-		if st != nil && st.resetQueued {
-			// Already have a stream error in flight. Don't send another.
-			return nil
-		}
-		return sc.countError("closed", http2streamError(id, http2ErrCodeStreamClosed))
-	}
-	if st.body == nil {
-		panic("internal error: should have a body in this state")
-	}
-
-	// Sender sending more than they'd declared?
-	if st.declBodyBytes != -1 && st.bodyBytes+int64(len(data)) > st.declBodyBytes {
-		st.body.CloseWithError(fmt.Errorf("sender tried to send more than declared Content-Length of %d bytes", st.declBodyBytes))
-		// RFC 7540, sec 8.1.2.6: A request or response is also malformed if the
-		// value of a content-length header field does not equal the sum of the
-		// DATA frame payload lengths that form the body.
-		return sc.countError("send_too_much", http2streamError(id, http2ErrCodeProtocol))
-	}
-	if f.Length > 0 {
-		// Check whether the client has flow control quota.
-		if st.inflow.available() < int32(f.Length) {
-			return sc.countError("flow_on_data_length", http2streamError(id, http2ErrCodeFlowControl))
-		}
-		st.inflow.take(int32(f.Length))
-
-		if len(data) > 0 {
-			wrote, err := st.body.Write(data)
-			if err != nil {
-				sc.sendWindowUpdate(nil, int(f.Length)-wrote)
-				return sc.countError("body_write_err", http2streamError(id, http2ErrCodeStreamClosed))
-			}
-			if wrote != len(data) {
-				panic("internal error: bad Writer")
-			}
-			st.bodyBytes += int64(len(data))
-		}
-
-		// Return any padded flow control now, since we won't
-		// refund it later on body reads.
-		if pad := int32(f.Length) - int32(len(data)); pad > 0 {
-			sc.sendWindowUpdate32(nil, pad)
-			sc.sendWindowUpdate32(st, pad)
-		}
-	}
-	if f.StreamEnded() {
-		st.endStream()
-	}
-	return nil
-}
-
-func (sc *http2serverConn) processGoAway(f *http2GoAwayFrame) error {
-	sc.serveG.check()
-	if f.ErrCode != http2ErrCodeNo {
-		sc.logf("http2: received GOAWAY %+v, starting graceful shutdown", f)
-	} else {
-		sc.vlogf("http2: received GOAWAY %+v, starting graceful shutdown", f)
-	}
-	sc.startGracefulShutdownInternal()
-	// http://tools.ietf.org/html/rfc7540#section-6.8
-	// We should not create any new streams, which means we should disable push.
-	sc.pushEnabled = false
-	return nil
-}
-
-// isPushed reports whether the stream is server-initiated.
-func (st *http2stream) isPushed() bool {
-	return st.id%2 == 0
-}
-
-// endStream closes a Request.Body's pipe. It is called when a DATA
-// frame says a request body is over (or after trailers).
-func (st *http2stream) endStream() {
-	sc := st.sc
-	sc.serveG.check()
-
-	if st.declBodyBytes != -1 && st.declBodyBytes != st.bodyBytes {
-		st.body.CloseWithError(fmt.Errorf("request declared a Content-Length of %d but only wrote %d bytes",
-			st.declBodyBytes, st.bodyBytes))
-	} else {
-		st.body.closeWithErrorAndCode(io.EOF, st.copyTrailersToHandlerRequest)
-		st.body.CloseWithError(io.EOF)
-	}
-	st.state = http2stateHalfClosedRemote
-}
-
-// copyTrailersToHandlerRequest is run in the Handler's goroutine in
-// its Request.Body.Read just before it gets io.EOF.
-func (st *http2stream) copyTrailersToHandlerRequest() {
-	for k, vv := range st.trailer {
-		if _, ok := st.reqTrailer[k]; ok {
-			// Only copy it over it was pre-declared.
-			st.reqTrailer[k] = vv
-		}
-	}
-}
-
-// onWriteTimeout is run on its own goroutine (from time.AfterFunc)
-// when the stream's WriteTimeout has fired.
-func (st *http2stream) onWriteTimeout() {
-	st.sc.writeFrameFromHandler(http2FrameWriteRequest{write: http2streamError(st.id, http2ErrCodeInternal)})
-}
-
-func (sc *http2serverConn) processHeaders(f *http2MetaHeadersFrame) error {
-	sc.serveG.check()
-	id := f.StreamID
-	if sc.inGoAway {
-		// Ignore.
-		return nil
-	}
-	// http://tools.ietf.org/html/rfc7540#section-5.1.1
-	// Streams initiated by a client MUST use odd-numbered stream
-	// identifiers. [...] An endpoint that receives an unexpected
-	// stream identifier MUST respond with a connection error
-	// (Section 5.4.1) of type PROTOCOL_ERROR.
-	if id%2 != 1 {
-		return sc.countError("headers_even", http2ConnectionError(http2ErrCodeProtocol))
-	}
-	// A HEADERS frame can be used to create a new stream or
-	// send a trailer for an open one. If we already have a stream
-	// open, let it process its own HEADERS frame (trailers at this
-	// point, if it's valid).
-	if st := sc.streams[f.StreamID]; st != nil {
-		if st.resetQueued {
-			// We're sending RST_STREAM to close the stream, so don't bother
-			// processing this frame.
-			return nil
-		}
-		// RFC 7540, sec 5.1: If an endpoint receives additional frames, other than
-		// WINDOW_UPDATE, PRIORITY, or RST_STREAM, for a stream that is in
-		// this state, it MUST respond with a stream error (Section 5.4.2) of
-		// type STREAM_CLOSED.
-		if st.state == http2stateHalfClosedRemote {
-			return sc.countError("headers_half_closed", http2streamError(id, http2ErrCodeStreamClosed))
-		}
-		return st.processTrailerHeaders(f)
-	}
-
-	// [...] The identifier of a newly established stream MUST be
-	// numerically greater than all streams that the initiating
-	// endpoint has opened or reserved. [...]  An endpoint that
-	// receives an unexpected stream identifier MUST respond with
-	// a connection error (Section 5.4.1) of type PROTOCOL_ERROR.
-	if id <= sc.maxClientStreamID {
-		return sc.countError("stream_went_down", http2ConnectionError(http2ErrCodeProtocol))
-	}
-	sc.maxClientStreamID = id
-
-	if sc.idleTimer != nil {
-		sc.idleTimer.Stop()
-	}
-
-	// http://tools.ietf.org/html/rfc7540#section-5.1.2
-	// [...] Endpoints MUST NOT exceed the limit set by their peer. An
-	// endpoint that receives a HEADERS frame that causes their
-	// advertised concurrent stream limit to be exceeded MUST treat
-	// this as a stream error (Section 5.4.2) of type PROTOCOL_ERROR
-	// or REFUSED_STREAM.
-	if sc.curClientStreams+1 > sc.advMaxStreams {
-		if sc.unackedSettings == 0 {
-			// They should know better.
-			return sc.countError("over_max_streams", http2streamError(id, http2ErrCodeProtocol))
-		}
-		// Assume it's a network race, where they just haven't
-		// received our last SETTINGS update. But actually
-		// this can't happen yet, because we don't yet provide
-		// a way for users to adjust server parameters at
-		// runtime.
-		return sc.countError("over_max_streams_race", http2streamError(id, http2ErrCodeRefusedStream))
-	}
-
-	initialState := http2stateOpen
-	if f.StreamEnded() {
-		initialState = http2stateHalfClosedRemote
-	}
-	st := sc.newStream(id, 0, initialState)
-
-	if f.HasPriority() {
-		if err := sc.checkPriority(f.StreamID, f.Priority); err != nil {
-			return err
-		}
-		sc.writeSched.AdjustStream(st.id, f.Priority)
-	}
-
-	rw, req, err := sc.newWriterAndRequest(st, f)
-	if err != nil {
-		return err
-	}
-	st.reqTrailer = req.Trailer
-	if st.reqTrailer != nil {
-		st.trailer = make(Header)
-	}
-	st.body = req.Body.(*http2requestBody).pipe // may be nil
-	st.declBodyBytes = req.ContentLength
-
-	handler := sc.handler.ServeHTTP
-	if f.Truncated {
-		// Their header list was too long. Send a 431 error.
-		handler = http2handleHeaderListTooLong
-	} else if err := http2checkValidHTTP2RequestHeaders(req.Header); err != nil {
-		handler = http2new400Handler(err)
-	}
-
-	// The net/http package sets the read deadline from the
-	// http.Server.ReadTimeout during the TLS handshake, but then
-	// passes the connection off to us with the deadline already
-	// set. Disarm it here after the request headers are read,
-	// similar to how the http1 server works. Here it's
-	// technically more like the http1 Server's ReadHeaderTimeout
-	// (in Go 1.8), though. That's a more sane option anyway.
-	if sc.hs.ReadTimeout != 0 {
-		sc.conn.SetReadDeadline(time.Time{})
-	}
-
-	go sc.runHandler(rw, req, handler)
-	return nil
-}
-
-func (st *http2stream) processTrailerHeaders(f *http2MetaHeadersFrame) error {
-	sc := st.sc
-	sc.serveG.check()
-	if st.gotTrailerHeader {
-		return sc.countError("dup_trailers", http2ConnectionError(http2ErrCodeProtocol))
-	}
-	st.gotTrailerHeader = true
-	if !f.StreamEnded() {
-		return sc.countError("trailers_not_ended", http2streamError(st.id, http2ErrCodeProtocol))
-	}
-
-	if len(f.PseudoFields()) > 0 {
-		return sc.countError("trailers_pseudo", http2streamError(st.id, http2ErrCodeProtocol))
-	}
-	if st.trailer != nil {
-		for _, hf := range f.RegularFields() {
-			key := sc.canonicalHeader(hf.Name)
-			if !httpguts.ValidTrailerHeader(key) {
-				// TODO: send more details to the peer somehow. But http2 has
-				// no way to send debug data at a stream level. Discuss with
-				// HTTP folk.
-				return sc.countError("trailers_bogus", http2streamError(st.id, http2ErrCodeProtocol))
-			}
-			st.trailer[key] = append(st.trailer[key], hf.Value)
-		}
-	}
-	st.endStream()
-	return nil
-}
-
-func (sc *http2serverConn) checkPriority(streamID uint32, p http2PriorityParam) error {
-	if streamID == p.StreamDep {
-		// Section 5.3.1: "A stream cannot depend on itself. An endpoint MUST treat
-		// this as a stream error (Section 5.4.2) of type PROTOCOL_ERROR."
-		// Section 5.3.3 says that a stream can depend on one of its dependencies,
-		// so it's only self-dependencies that are forbidden.
-		return sc.countError("priority", http2streamError(streamID, http2ErrCodeProtocol))
-	}
-	return nil
-}
-
-func (sc *http2serverConn) processPriority(f *http2PriorityFrame) error {
-	if sc.inGoAway {
-		return nil
-	}
-	if err := sc.checkPriority(f.StreamID, f.http2PriorityParam); err != nil {
-		return err
-	}
-	sc.writeSched.AdjustStream(f.StreamID, f.http2PriorityParam)
-	return nil
-}
-
-func (sc *http2serverConn) newStream(id, pusherID uint32, state http2streamState) *http2stream {
-	sc.serveG.check()
-	if id == 0 {
-		panic("internal error: cannot create stream with id 0")
-	}
-
-	ctx, cancelCtx := context.WithCancel(sc.baseCtx)
-	st := &http2stream{
-		sc:        sc,
-		id:        id,
-		state:     state,
-		ctx:       ctx,
-		cancelCtx: cancelCtx,
-	}
-	st.cw.Init()
-	st.flow.conn = &sc.flow // link to conn-level counter
-	st.flow.add(sc.initialStreamSendWindowSize)
-	st.inflow.conn = &sc.inflow // link to conn-level counter
-	st.inflow.add(sc.srv.initialStreamRecvWindowSize())
-	if sc.hs.WriteTimeout != 0 {
-		st.writeDeadline = time.AfterFunc(sc.hs.WriteTimeout, st.onWriteTimeout)
-	}
-
-	sc.streams[id] = st
-	sc.writeSched.OpenStream(st.id, http2OpenStreamOptions{PusherID: pusherID})
-	if st.isPushed() {
-		sc.curPushedStreams++
-	} else {
-		sc.curClientStreams++
-	}
-	if sc.curOpenStreams() == 1 {
-		sc.setConnState(StateActive)
-	}
-
-	return st
-}
-
-func (sc *http2serverConn) newWriterAndRequest(st *http2stream, f *http2MetaHeadersFrame) (*http2responseWriter, *Request, error) {
-	sc.serveG.check()
-
-	rp := http2requestParam{
-		method:    f.PseudoValue("method"),
-		scheme:    f.PseudoValue("scheme"),
-		authority: f.PseudoValue("authority"),
-		path:      f.PseudoValue("path"),
-	}
-
-	isConnect := rp.method == "CONNECT"
-	if isConnect {
-		if rp.path != "" || rp.scheme != "" || rp.authority == "" {
-			return nil, nil, sc.countError("bad_connect", http2streamError(f.StreamID, http2ErrCodeProtocol))
-		}
-	} else if rp.method == "" || rp.path == "" || (rp.scheme != "https" && rp.scheme != "http") {
-		// See 8.1.2.6 Malformed Requests and Responses:
-		//
-		// Malformed requests or responses that are detected
-		// MUST be treated as a stream error (Section 5.4.2)
-		// of type PROTOCOL_ERROR."
-		//
-		// 8.1.2.3 Request Pseudo-Header Fields
-		// "All HTTP/2 requests MUST include exactly one valid
-		// value for the :method, :scheme, and :path
-		// pseudo-header fields"
-		return nil, nil, sc.countError("bad_path_method", http2streamError(f.StreamID, http2ErrCodeProtocol))
-	}
-
-	bodyOpen := !f.StreamEnded()
-	if rp.method == "HEAD" && bodyOpen {
-		// HEAD requests can't have bodies
-		return nil, nil, sc.countError("head_body", http2streamError(f.StreamID, http2ErrCodeProtocol))
-	}
-
-	rp.header = make(Header)
-	for _, hf := range f.RegularFields() {
-		rp.header.Add(sc.canonicalHeader(hf.Name), hf.Value)
-	}
-	if rp.authority == "" {
-		rp.authority = rp.header.Get("Host")
-	}
-
-	rw, req, err := sc.newWriterAndRequestNoBody(st, rp)
-	if err != nil {
-		return nil, nil, err
-	}
-	if bodyOpen {
-		if vv, ok := rp.header["Content-Length"]; ok {
-			if cl, err := strconv.ParseUint(vv[0], 10, 63); err == nil {
-				req.ContentLength = int64(cl)
-			} else {
-				req.ContentLength = 0
-			}
-		} else {
-			req.ContentLength = -1
-		}
-		req.Body.(*http2requestBody).pipe = &http2pipe{
-			b: &http2dataBuffer{expected: req.ContentLength},
-		}
-	}
-	return rw, req, nil
-}
-
-type http2requestParam struct {
-	method                  string
-	scheme, authority, path string
-	header                  Header
-}
-
-func (sc *http2serverConn) newWriterAndRequestNoBody(st *http2stream, rp http2requestParam) (*http2responseWriter, *Request, error) {
-	sc.serveG.check()
-
-	var tlsState *tls.ConnectionState // nil if not scheme https
-	if rp.scheme == "https" {
-		tlsState = sc.tlsState
-	}
-
-	needsContinue := rp.header.Get("Expect") == "100-continue"
-	if needsContinue {
-		rp.header.Del("Expect")
-	}
-	// Merge Cookie headers into one "; "-delimited value.
-	if cookies := rp.header["Cookie"]; len(cookies) > 1 {
-		rp.header.Set("Cookie", strings.Join(cookies, "; "))
-	}
-
-	// Setup Trailers
-	var trailer Header
-	for _, v := range rp.header["Trailer"] {
-		for _, key := range strings.Split(v, ",") {
-			key = CanonicalHeaderKey(textproto.TrimString(key))
-			switch key {
-			case "Transfer-Encoding", "Trailer", "Content-Length":
-				// Bogus. (copy of http1 rules)
-				// Ignore.
-			default:
-				if trailer == nil {
-					trailer = make(Header)
-				}
-				trailer[key] = nil
-			}
-		}
-	}
-	delete(rp.header, "Trailer")
-
-	var url_ *url.URL
-	var requestURI string
-	if rp.method == "CONNECT" {
-		url_ = &url.URL{Host: rp.authority}
-		requestURI = rp.authority // mimic HTTP/1 server behavior
-	} else {
-		var err error
-		url_, err = url.ParseRequestURI(rp.path)
-		if err != nil {
-			return nil, nil, sc.countError("bad_path", http2streamError(st.id, http2ErrCodeProtocol))
-		}
-		requestURI = rp.path
-	}
-
-	body := &http2requestBody{
-		conn:          sc,
-		stream:        st,
-		needsContinue: needsContinue,
-	}
-	req := &Request{
-		Method:     rp.method,
-		URL:        url_,
-		RemoteAddr: sc.remoteAddrStr,
-		Header:     rp.header,
-		RequestURI: requestURI,
-		Proto:      "HTTP/2.0",
-		ProtoMajor: 2,
-		ProtoMinor: 0,
-		TLS:        tlsState,
-		Host:       rp.authority,
-		Body:       body,
-		Trailer:    trailer,
-	}
-	req = req.WithContext(st.ctx)
-
-	rws := http2responseWriterStatePool.Get().(*http2responseWriterState)
-	bwSave := rws.bw
-	*rws = http2responseWriterState{} // zero all the fields
-	rws.conn = sc
-	rws.bw = bwSave
-	rws.bw.Reset(http2chunkWriter{rws})
-	rws.stream = st
-	rws.req = req
-	rws.body = body
-
-	rw := &http2responseWriter{rws: rws}
-	return rw, req, nil
-}
-
-// Run on its own goroutine.
-func (sc *http2serverConn) runHandler(rw *http2responseWriter, req *Request, handler func(ResponseWriter, *Request)) {
-	didPanic := true
-	defer func() {
-		rw.rws.stream.cancelCtx()
-		if didPanic {
-			e := recover()
-			sc.writeFrameFromHandler(http2FrameWriteRequest{
-				write:  http2handlerPanicRST{rw.rws.stream.id},
-				stream: rw.rws.stream,
-			})
-			// Same as net/http:
-			if e != nil && e != ErrAbortHandler {
-				const size = 64 << 10
-				buf := make([]byte, size)
-				buf = buf[:runtime.Stack(buf, false)]
-				sc.logf("http2: panic serving %v: %v\n%s", sc.conn.RemoteAddr(), e, buf)
-			}
-			return
-		}
-		rw.handlerDone()
-	}()
-	handler(rw, req)
-	didPanic = false
-}
-
-func http2handleHeaderListTooLong(w ResponseWriter, r *Request) {
-	// 10.5.1 Limits on Header Block Size:
-	// .. "A server that receives a larger header block than it is
-	// willing to handle can send an HTTP 431 (Request Header Fields Too
-	// Large) status code"
-	const statusRequestHeaderFieldsTooLarge = 431 // only in Go 1.6+
-	w.WriteHeader(statusRequestHeaderFieldsTooLarge)
-	io.WriteString(w, "<h1>HTTP Error 431</h1><p>Request Header Field(s) Too Large</p>")
-}
-
-// called from handler goroutines.
-// h may be nil.
-func (sc *http2serverConn) writeHeaders(st *http2stream, headerData *http2writeResHeaders) error {
-	sc.serveG.checkNotOn() // NOT on
-	var errc chan error
-	if headerData.h != nil {
-		// If there's a header map (which we don't own), so we have to block on
-		// waiting for this frame to be written, so an http.Flush mid-handler
-		// writes out the correct value of keys, before a handler later potentially
-		// mutates it.
-		errc = http2errChanPool.Get().(chan error)
-	}
-	if err := sc.writeFrameFromHandler(http2FrameWriteRequest{
-		write:  headerData,
-		stream: st,
-		done:   errc,
-	}); err != nil {
-		return err
-	}
-	if errc != nil {
-		select {
-		case err := <-errc:
-			http2errChanPool.Put(errc)
-			return err
-		case <-sc.doneServing:
-			return http2errClientDisconnected
-		case <-st.cw:
-			return http2errStreamClosed
-		}
-	}
-	return nil
-}
-
-// called from handler goroutines.
-func (sc *http2serverConn) write100ContinueHeaders(st *http2stream) {
-	sc.writeFrameFromHandler(http2FrameWriteRequest{
-		write:  http2write100ContinueHeadersFrame{st.id},
-		stream: st,
-	})
-}
-
-// A bodyReadMsg tells the server loop that the http.Handler read n
-// bytes of the DATA from the client on the given stream.
-type http2bodyReadMsg struct {
-	st *http2stream
-	n  int
-}
-
-// called from handler goroutines.
-// Notes that the handler for the given stream ID read n bytes of its body
-// and schedules flow control tokens to be sent.
-func (sc *http2serverConn) noteBodyReadFromHandler(st *http2stream, n int, err error) {
-	sc.serveG.checkNotOn() // NOT on
-	if n > 0 {
-		select {
-		case sc.bodyReadCh <- http2bodyReadMsg{st, n}:
-		case <-sc.doneServing:
-		}
-	}
-}
-
-func (sc *http2serverConn) noteBodyRead(st *http2stream, n int) {
-	sc.serveG.check()
-	sc.sendWindowUpdate(nil, n) // conn-level
-	if st.state != http2stateHalfClosedRemote && st.state != http2stateClosed {
-		// Don't send this WINDOW_UPDATE if the stream is closed
-		// remotely.
-		sc.sendWindowUpdate(st, n)
-	}
-}
-
-// st may be nil for conn-level
-func (sc *http2serverConn) sendWindowUpdate(st *http2stream, n int) {
-	sc.serveG.check()
-	// "The legal range for the increment to the flow control
-	// window is 1 to 2^31-1 (2,147,483,647) octets."
-	// A Go Read call on 64-bit machines could in theory read
-	// a larger Read than this. Very unlikely, but we handle it here
-	// rather than elsewhere for now.
-	const maxUint31 = 1<<31 - 1
-	for n >= maxUint31 {
-		sc.sendWindowUpdate32(st, maxUint31)
-		n -= maxUint31
-	}
-	sc.sendWindowUpdate32(st, int32(n))
-}
-
-// st may be nil for conn-level
-func (sc *http2serverConn) sendWindowUpdate32(st *http2stream, n int32) {
-	sc.serveG.check()
-	if n == 0 {
-		return
-	}
-	if n < 0 {
-		panic("negative update")
-	}
-	var streamID uint32
-	if st != nil {
-		streamID = st.id
-	}
-	sc.writeFrame(http2FrameWriteRequest{
-		write:  http2writeWindowUpdate{streamID: streamID, n: uint32(n)},
-		stream: st,
-	})
-	var ok bool
-	if st == nil {
-		ok = sc.inflow.add(n)
-	} else {
-		ok = st.inflow.add(n)
-	}
-	if !ok {
-		panic("internal error; sent too many window updates without decrements?")
-	}
-}
-
-// requestBody is the Handler's Request.Body type.
-// Read and Close may be called concurrently.
-type http2requestBody struct {
-	_             http2incomparable
-	stream        *http2stream
-	conn          *http2serverConn
-	closed        bool       // for use by Close only
-	sawEOF        bool       // for use by Read only
-	pipe          *http2pipe // non-nil if we have a HTTP entity message body
-	needsContinue bool       // need to send a 100-continue
-}
-
-func (b *http2requestBody) Close() error {
-	if b.pipe != nil && !b.closed {
-		b.pipe.BreakWithError(http2errClosedBody)
-	}
-	b.closed = true
-	return nil
-}
-
-func (b *http2requestBody) Read(p []byte) (n int, err error) {
-	if b.needsContinue {
-		b.needsContinue = false
-		b.conn.write100ContinueHeaders(b.stream)
-	}
-	if b.pipe == nil || b.sawEOF {
-		return 0, io.EOF
-	}
-	n, err = b.pipe.Read(p)
-	if err == io.EOF {
-		b.sawEOF = true
-	}
-	if b.conn == nil && http2inTests {
-		return
-	}
-	b.conn.noteBodyReadFromHandler(b.stream, n, err)
-	return
-}
-
-// responseWriter is the http.ResponseWriter implementation. It's
-// intentionally small (1 pointer wide) to minimize garbage. The
-// responseWriterState pointer inside is zeroed at the end of a
-// request (in handlerDone) and calls on the responseWriter thereafter
-// simply crash (caller's mistake), but the much larger responseWriterState
-// and buffers are reused between multiple requests.
-type http2responseWriter struct {
-	rws *http2responseWriterState
-}
-
-// Optional http.ResponseWriter interfaces implemented.
-var (
-	_ CloseNotifier     = (*http2responseWriter)(nil)
-	_ Flusher           = (*http2responseWriter)(nil)
-	_ http2stringWriter = (*http2responseWriter)(nil)
-)
-
-type http2responseWriterState struct {
-	// immutable within a request:
-	stream *http2stream
-	req    *Request
-	body   *http2requestBody // to close at end of request, if DATA frames didn't
-	conn   *http2serverConn
-
-	// TODO: adjust buffer writing sizes based on server config, frame size updates from peer, etc
-	bw *bufio.Writer // writing to a chunkWriter{this *responseWriterState}
-
-	// mutated by http.Handler goroutine:
-	handlerHeader Header   // nil until called
-	snapHeader    Header   // snapshot of handlerHeader at WriteHeader time
-	trailers      []string // set in writeChunk
-	status        int      // status code passed to WriteHeader
-	wroteHeader   bool     // WriteHeader called (explicitly or implicitly). Not necessarily sent to user yet.
-	sentHeader    bool     // have we sent the header frame?
-	handlerDone   bool     // handler has finished
-	dirty         bool     // a Write failed; don't reuse this responseWriterState
-
-	sentContentLen int64 // non-zero if handler set a Content-Length header
-	wroteBytes     int64
-
-	closeNotifierMu sync.Mutex // guards closeNotifierCh
-	closeNotifierCh chan bool  // nil until first used
-}
-
-type http2chunkWriter struct{ rws *http2responseWriterState }
-
-func (cw http2chunkWriter) Write(p []byte) (n int, err error) { return cw.rws.writeChunk(p) }
-
-func (rws *http2responseWriterState) hasTrailers() bool { return len(rws.trailers) > 0 }
-
-func (rws *http2responseWriterState) hasNonemptyTrailers() bool {
-	for _, trailer := range rws.trailers {
-		if _, ok := rws.handlerHeader[trailer]; ok {
-			return true
-		}
-	}
-	return false
-}
-
-// declareTrailer is called for each Trailer header when the
-// response header is written. It notes that a header will need to be
-// written in the trailers at the end of the response.
-func (rws *http2responseWriterState) declareTrailer(k string) {
-	k = CanonicalHeaderKey(k)
-	if !httpguts.ValidTrailerHeader(k) {
-		// Forbidden by RFC 7230, section 4.1.2.
-		rws.conn.logf("ignoring invalid trailer %q", k)
-		return
-	}
-	if !http2strSliceContains(rws.trailers, k) {
-		rws.trailers = append(rws.trailers, k)
-	}
-}
-
-// writeChunk writes chunks from the bufio.Writer. But because
-// bufio.Writer may bypass its chunking, sometimes p may be
-// arbitrarily large.
-//
-// writeChunk is also responsible (on the first chunk) for sending the
-// HEADER response.
-func (rws *http2responseWriterState) writeChunk(p []byte) (n int, err error) {
-	if !rws.wroteHeader {
-		rws.writeHeader(200)
-	}
-
-	isHeadResp := rws.req.Method == "HEAD"
-	if !rws.sentHeader {
-		rws.sentHeader = true
-		var ctype, clen string
-		if clen = rws.snapHeader.Get("Content-Length"); clen != "" {
-			rws.snapHeader.Del("Content-Length")
-			if cl, err := strconv.ParseUint(clen, 10, 63); err == nil {
-				rws.sentContentLen = int64(cl)
-			} else {
-				clen = ""
-			}
-		}
-		if clen == "" && rws.handlerDone && http2bodyAllowedForStatus(rws.status) && (len(p) > 0 || !isHeadResp) {
-			clen = strconv.Itoa(len(p))
-		}
-		_, hasContentType := rws.snapHeader["Content-Type"]
-		// If the Content-Encoding is non-blank, we shouldn't
-		// sniff the body. See Issue golang.org/issue/31753.
-		ce := rws.snapHeader.Get("Content-Encoding")
-		hasCE := len(ce) > 0
-		if !hasCE && !hasContentType && http2bodyAllowedForStatus(rws.status) && len(p) > 0 {
-			ctype = DetectContentType(p)
-		}
-		var date string
-		if _, ok := rws.snapHeader["Date"]; !ok {
-			// TODO(bradfitz): be faster here, like net/http? measure.
-			date = time.Now().UTC().Format(TimeFormat)
-		}
-
-		for _, v := range rws.snapHeader["Trailer"] {
-			http2foreachHeaderElement(v, rws.declareTrailer)
-		}
-
-		// "Connection" headers aren't allowed in HTTP/2 (RFC 7540, 8.1.2.2),
-		// but respect "Connection" == "close" to mean sending a GOAWAY and tearing
-		// down the TCP connection when idle, like we do for HTTP/1.
-		// TODO: remove more Connection-specific header fields here, in addition
-		// to "Connection".
-		if _, ok := rws.snapHeader["Connection"]; ok {
-			v := rws.snapHeader.Get("Connection")
-			delete(rws.snapHeader, "Connection")
-			if v == "close" {
-				rws.conn.startGracefulShutdown()
-			}
-		}
-
-		endStream := (rws.handlerDone && !rws.hasTrailers() && len(p) == 0) || isHeadResp
-		err = rws.conn.writeHeaders(rws.stream, &http2writeResHeaders{
-			streamID:      rws.stream.id,
-			httpResCode:   rws.status,
-			h:             rws.snapHeader,
-			endStream:     endStream,
-			contentType:   ctype,
-			contentLength: clen,
-			date:          date,
-		})
-		if err != nil {
-			rws.dirty = true
-			return 0, err
-		}
-		if endStream {
-			return 0, nil
-		}
-	}
-	if isHeadResp {
-		return len(p), nil
-	}
-	if len(p) == 0 && !rws.handlerDone {
-		return 0, nil
-	}
-
-	if rws.handlerDone {
-		rws.promoteUndeclaredTrailers()
-	}
-
-	// only send trailers if they have actually been defined by the
-	// server handler.
-	hasNonemptyTrailers := rws.hasNonemptyTrailers()
-	endStream := rws.handlerDone && !hasNonemptyTrailers
-	if len(p) > 0 || endStream {
-		// only send a 0 byte DATA frame if we're ending the stream.
-		if err := rws.conn.writeDataFromHandler(rws.stream, p, endStream); err != nil {
-			rws.dirty = true
-			return 0, err
-		}
-	}
-
-	if rws.handlerDone && hasNonemptyTrailers {
-		err = rws.conn.writeHeaders(rws.stream, &http2writeResHeaders{
-			streamID:  rws.stream.id,
-			h:         rws.handlerHeader,
-			trailers:  rws.trailers,
-			endStream: true,
-		})
-		if err != nil {
-			rws.dirty = true
-		}
-		return len(p), err
-	}
-	return len(p), nil
-}
-
-// TrailerPrefix is a magic prefix for ResponseWriter.Header map keys
-// that, if present, signals that the map entry is actually for
-// the response trailers, and not the response headers. The prefix
-// is stripped after the ServeHTTP call finishes and the values are
-// sent in the trailers.
-//
-// This mechanism is intended only for trailers that are not known
-// prior to the headers being written. If the set of trailers is fixed
-// or known before the header is written, the normal Go trailers mechanism
-// is preferred:
-//    https://golang.org/pkg/net/http/#ResponseWriter
-//    https://golang.org/pkg/net/http/#example_ResponseWriter_trailers
-const http2TrailerPrefix = "Trailer:"
-
-// promoteUndeclaredTrailers permits http.Handlers to set trailers
-// after the header has already been flushed. Because the Go
-// ResponseWriter interface has no way to set Trailers (only the
-// Header), and because we didn't want to expand the ResponseWriter
-// interface, and because nobody used trailers, and because RFC 7230
-// says you SHOULD (but not must) predeclare any trailers in the
-// header, the official ResponseWriter rules said trailers in Go must
-// be predeclared, and then we reuse the same ResponseWriter.Header()
-// map to mean both Headers and Trailers. When it's time to write the
-// Trailers, we pick out the fields of Headers that were declared as
-// trailers. That worked for a while, until we found the first major
-// user of Trailers in the wild: gRPC (using them only over http2),
-// and gRPC libraries permit setting trailers mid-stream without
-// predeclaring them. So: change of plans. We still permit the old
-// way, but we also permit this hack: if a Header() key begins with
-// "Trailer:", the suffix of that key is a Trailer. Because ':' is an
-// invalid token byte anyway, there is no ambiguity. (And it's already
-// filtered out) It's mildly hacky, but not terrible.
-//
-// This method runs after the Handler is done and promotes any Header
-// fields to be trailers.
-func (rws *http2responseWriterState) promoteUndeclaredTrailers() {
-	for k, vv := range rws.handlerHeader {
-		if !strings.HasPrefix(k, http2TrailerPrefix) {
-			continue
-		}
-		trailerKey := strings.TrimPrefix(k, http2TrailerPrefix)
-		rws.declareTrailer(trailerKey)
-		rws.handlerHeader[CanonicalHeaderKey(trailerKey)] = vv
-	}
-
-	if len(rws.trailers) > 1 {
-		sorter := http2sorterPool.Get().(*http2sorter)
-		sorter.SortStrings(rws.trailers)
-		http2sorterPool.Put(sorter)
-	}
-}
-
-func (w *http2responseWriter) Flush() {
-	rws := w.rws
-	if rws == nil {
-		panic("Header called after Handler finished")
-	}
-	if rws.bw.Buffered() > 0 {
-		if err := rws.bw.Flush(); err != nil {
-			// Ignore the error. The frame writer already knows.
-			return
-		}
-	} else {
-		// The bufio.Writer won't call chunkWriter.Write
-		// (writeChunk with zero bytes, so we have to do it
-		// ourselves to force the HTTP response header and/or
-		// final DATA frame (with END_STREAM) to be sent.
-		rws.writeChunk(nil)
-	}
-}
-
-func (w *http2responseWriter) CloseNotify() <-chan bool {
-	rws := w.rws
-	if rws == nil {
-		panic("CloseNotify called after Handler finished")
-	}
-	rws.closeNotifierMu.Lock()
-	ch := rws.closeNotifierCh
-	if ch == nil {
-		ch = make(chan bool, 1)
-		rws.closeNotifierCh = ch
-		cw := rws.stream.cw
-		go func() {
-			cw.Wait() // wait for close
-			ch <- true
-		}()
-	}
-	rws.closeNotifierMu.Unlock()
-	return ch
-}
-
-func (w *http2responseWriter) Header() Header {
-	rws := w.rws
-	if rws == nil {
-		panic("Header called after Handler finished")
-	}
-	if rws.handlerHeader == nil {
-		rws.handlerHeader = make(Header)
-	}
-	return rws.handlerHeader
-}
-
-// checkWriteHeaderCode is a copy of net/http's checkWriteHeaderCode.
-func http2checkWriteHeaderCode(code int) {
-	// Issue 22880: require valid WriteHeader status codes.
-	// For now we only enforce that it's three digits.
-	// In the future we might block things over 599 (600 and above aren't defined
-	// at http://httpwg.org/specs/rfc7231.html#status.codes)
-	// and we might block under 200 (once we have more mature 1xx support).
-	// But for now any three digits.
-	//
-	// We used to send "HTTP/1.1 000 0" on the wire in responses but there's
-	// no equivalent bogus thing we can realistically send in HTTP/2,
-	// so we'll consistently panic instead and help people find their bugs
-	// early. (We can't return an error from WriteHeader even if we wanted to.)
-	if code < 100 || code > 999 {
-		panic(fmt.Sprintf("invalid WriteHeader code %v", code))
-	}
-}
-
-func (w *http2responseWriter) WriteHeader(code int) {
-	rws := w.rws
-	if rws == nil {
-		panic("WriteHeader called after Handler finished")
-	}
-	rws.writeHeader(code)
-}
-
-func (rws *http2responseWriterState) writeHeader(code int) {
-	if !rws.wroteHeader {
-		http2checkWriteHeaderCode(code)
-		rws.wroteHeader = true
-		rws.status = code
-		if len(rws.handlerHeader) > 0 {
-			rws.snapHeader = http2cloneHeader(rws.handlerHeader)
-		}
-	}
-}
-
-func http2cloneHeader(h Header) Header {
-	h2 := make(Header, len(h))
-	for k, vv := range h {
-		vv2 := make([]string, len(vv))
-		copy(vv2, vv)
-		h2[k] = vv2
-	}
-	return h2
-}
-
-// The Life Of A Write is like this:
-//
-// * Handler calls w.Write or w.WriteString ->
-// * -> rws.bw (*bufio.Writer) ->
-// * (Handler might call Flush)
-// * -> chunkWriter{rws}
-// * -> responseWriterState.writeChunk(p []byte)
-// * -> responseWriterState.writeChunk (most of the magic; see comment there)
-func (w *http2responseWriter) Write(p []byte) (n int, err error) {
-	return w.write(len(p), p, "")
-}
-
-func (w *http2responseWriter) WriteString(s string) (n int, err error) {
-	return w.write(len(s), nil, s)
-}
-
-// either dataB or dataS is non-zero.
-func (w *http2responseWriter) write(lenData int, dataB []byte, dataS string) (n int, err error) {
-	rws := w.rws
-	if rws == nil {
-		panic("Write called after Handler finished")
-	}
-	if !rws.wroteHeader {
-		w.WriteHeader(200)
-	}
-	if !http2bodyAllowedForStatus(rws.status) {
-		return 0, ErrBodyNotAllowed
-	}
-	rws.wroteBytes += int64(len(dataB)) + int64(len(dataS)) // only one can be set
-	if rws.sentContentLen != 0 && rws.wroteBytes > rws.sentContentLen {
-		// TODO: send a RST_STREAM
-		return 0, errors.New("http2: handler wrote more than declared Content-Length")
-	}
-
-	if dataB != nil {
-		return rws.bw.Write(dataB)
-	} else {
-		return rws.bw.WriteString(dataS)
-	}
-}
-
-func (w *http2responseWriter) handlerDone() {
-	rws := w.rws
-	dirty := rws.dirty
-	rws.handlerDone = true
-	w.Flush()
-	w.rws = nil
-	if !dirty {
-		// Only recycle the pool if all prior Write calls to
-		// the serverConn goroutine completed successfully. If
-		// they returned earlier due to resets from the peer
-		// there might still be write goroutines outstanding
-		// from the serverConn referencing the rws memory. See
-		// issue 20704.
-		http2responseWriterStatePool.Put(rws)
-	}
-}
-
-// Push errors.
-var (
-	http2ErrRecursivePush    = errors.New("http2: recursive push not allowed")
-	http2ErrPushLimitReached = errors.New("http2: push would exceed peer's SETTINGS_MAX_CONCURRENT_STREAMS")
-)
-
-var _ Pusher = (*http2responseWriter)(nil)
-
-func (w *http2responseWriter) Push(target string, opts *PushOptions) error {
-	st := w.rws.stream
-	sc := st.sc
-	sc.serveG.checkNotOn()
-
-	// No recursive pushes: "PUSH_PROMISE frames MUST only be sent on a peer-initiated stream."
-	// http://tools.ietf.org/html/rfc7540#section-6.6
-	if st.isPushed() {
-		return http2ErrRecursivePush
-	}
-
-	if opts == nil {
-		opts = new(PushOptions)
-	}
-
-	// Default options.
-	if opts.Method == "" {
-		opts.Method = "GET"
-	}
-	if opts.Header == nil {
-		opts.Header = Header{}
-	}
-	wantScheme := "http"
-	if w.rws.req.TLS != nil {
-		wantScheme = "https"
-	}
-
-	// Validate the request.
-	u, err := url.Parse(target)
-	if err != nil {
-		return err
-	}
-	if u.Scheme == "" {
-		if !strings.HasPrefix(target, "/") {
-			return fmt.Errorf("target must be an absolute URL or an absolute path: %q", target)
-		}
-		u.Scheme = wantScheme
-		u.Host = w.rws.req.Host
-	} else {
-		if u.Scheme != wantScheme {
-			return fmt.Errorf("cannot push URL with scheme %q from request with scheme %q", u.Scheme, wantScheme)
-		}
-		if u.Host == "" {
-			return errors.New("URL must have a host")
-		}
-	}
-	for k := range opts.Header {
-		if strings.HasPrefix(k, ":") {
-			return fmt.Errorf("promised request headers cannot include pseudo header %q", k)
-		}
-		// These headers are meaningful only if the request has a body,
-		// but PUSH_PROMISE requests cannot have a body.
-		// http://tools.ietf.org/html/rfc7540#section-8.2
-		// Also disallow Host, since the promised URL must be absolute.
-		if http2asciiEqualFold(k, "content-length") ||
-			http2asciiEqualFold(k, "content-encoding") ||
-			http2asciiEqualFold(k, "trailer") ||
-			http2asciiEqualFold(k, "te") ||
-			http2asciiEqualFold(k, "expect") ||
-			http2asciiEqualFold(k, "host") {
-			return fmt.Errorf("promised request headers cannot include %q", k)
-		}
-	}
-	if err := http2checkValidHTTP2RequestHeaders(opts.Header); err != nil {
-		return err
-	}
-
-	// The RFC effectively limits promised requests to GET and HEAD:
-	// "Promised requests MUST be cacheable [GET, HEAD, or POST], and MUST be safe [GET or HEAD]"
-	// http://tools.ietf.org/html/rfc7540#section-8.2
-	if opts.Method != "GET" && opts.Method != "HEAD" {
-		return fmt.Errorf("method %q must be GET or HEAD", opts.Method)
-	}
-
-	msg := &http2startPushRequest{
-		parent: st,
-		method: opts.Method,
-		url:    u,
-		header: http2cloneHeader(opts.Header),
-		done:   http2errChanPool.Get().(chan error),
-	}
-
-	select {
-	case <-sc.doneServing:
-		return http2errClientDisconnected
-	case <-st.cw:
-		return http2errStreamClosed
-	case sc.serveMsgCh <- msg:
-	}
-
-	select {
-	case <-sc.doneServing:
-		return http2errClientDisconnected
-	case <-st.cw:
-		return http2errStreamClosed
-	case err := <-msg.done:
-		http2errChanPool.Put(msg.done)
-		return err
-	}
-}
-
-type http2startPushRequest struct {
-	parent *http2stream
-	method string
-	url    *url.URL
-	header Header
-	done   chan error
-}
-
-func (sc *http2serverConn) startPush(msg *http2startPushRequest) {
-	sc.serveG.check()
-
-	// http://tools.ietf.org/html/rfc7540#section-6.6.
-	// PUSH_PROMISE frames MUST only be sent on a peer-initiated stream that
-	// is in either the "open" or "half-closed (remote)" state.
-	if msg.parent.state != http2stateOpen && msg.parent.state != http2stateHalfClosedRemote {
-		// responseWriter.Push checks that the stream is peer-initiated.
-		msg.done <- http2errStreamClosed
-		return
-	}
-
-	// http://tools.ietf.org/html/rfc7540#section-6.6.
-	if !sc.pushEnabled {
-		msg.done <- ErrNotSupported
-		return
-	}
-
-	// PUSH_PROMISE frames must be sent in increasing order by stream ID, so
-	// we allocate an ID for the promised stream lazily, when the PUSH_PROMISE
-	// is written. Once the ID is allocated, we start the request handler.
-	allocatePromisedID := func() (uint32, error) {
-		sc.serveG.check()
-
-		// Check this again, just in case. Technically, we might have received
-		// an updated SETTINGS by the time we got around to writing this frame.
-		if !sc.pushEnabled {
-			return 0, ErrNotSupported
-		}
-		// http://tools.ietf.org/html/rfc7540#section-6.5.2.
-		if sc.curPushedStreams+1 > sc.clientMaxStreams {
-			return 0, http2ErrPushLimitReached
-		}
-
-		// http://tools.ietf.org/html/rfc7540#section-5.1.1.
-		// Streams initiated by the server MUST use even-numbered identifiers.
-		// A server that is unable to establish a new stream identifier can send a GOAWAY
-		// frame so that the client is forced to open a new connection for new streams.
-		if sc.maxPushPromiseID+2 >= 1<<31 {
-			sc.startGracefulShutdownInternal()
-			return 0, http2ErrPushLimitReached
-		}
-		sc.maxPushPromiseID += 2
-		promisedID := sc.maxPushPromiseID
-
-		// http://tools.ietf.org/html/rfc7540#section-8.2.
-		// Strictly speaking, the new stream should start in "reserved (local)", then
-		// transition to "half closed (remote)" after sending the initial HEADERS, but
-		// we start in "half closed (remote)" for simplicity.
-		// See further comments at the definition of stateHalfClosedRemote.
-		promised := sc.newStream(promisedID, msg.parent.id, http2stateHalfClosedRemote)
-		rw, req, err := sc.newWriterAndRequestNoBody(promised, http2requestParam{
-			method:    msg.method,
-			scheme:    msg.url.Scheme,
-			authority: msg.url.Host,
-			path:      msg.url.RequestURI(),
-			header:    http2cloneHeader(msg.header), // clone since handler runs concurrently with writing the PUSH_PROMISE
-		})
-		if err != nil {
-			// Should not happen, since we've already validated msg.url.
-			panic(fmt.Sprintf("newWriterAndRequestNoBody(%+v): %v", msg.url, err))
-		}
-
-		go sc.runHandler(rw, req, sc.handler.ServeHTTP)
-		return promisedID, nil
-	}
-
-	sc.writeFrame(http2FrameWriteRequest{
-		write: &http2writePushPromise{
-			streamID:           msg.parent.id,
-			method:             msg.method,
-			url:                msg.url,
-			h:                  msg.header,
-			allocatePromisedID: allocatePromisedID,
-		},
-		stream: msg.parent,
-		done:   msg.done,
-	})
-}
-
-// foreachHeaderElement splits v according to the "#rule" construction
-// in RFC 7230 section 7 and calls fn for each non-empty element.
-func http2foreachHeaderElement(v string, fn func(string)) {
-	v = textproto.TrimString(v)
-	if v == "" {
-		return
-	}
-	if !strings.Contains(v, ",") {
-		fn(v)
-		return
-	}
-	for _, f := range strings.Split(v, ",") {
-		if f = textproto.TrimString(f); f != "" {
-			fn(f)
-		}
-	}
-}
-
-// From http://httpwg.org/specs/rfc7540.html#rfc.section.8.1.2.2
-var http2connHeaders = []string{
-	"Connection",
-	"Keep-Alive",
-	"Proxy-Connection",
-	"Transfer-Encoding",
-	"Upgrade",
-}
-
-// checkValidHTTP2RequestHeaders checks whether h is a valid HTTP/2 request,
-// per RFC 7540 Section 8.1.2.2.
-// The returned error is reported to users.
-func http2checkValidHTTP2RequestHeaders(h Header) error {
-	for _, k := range http2connHeaders {
-		if _, ok := h[k]; ok {
-			return fmt.Errorf("request header %q is not valid in HTTP/2", k)
-		}
-	}
-	te := h["Te"]
-	if len(te) > 0 && (len(te) > 1 || (te[0] != "trailers" && te[0] != "")) {
-		return errors.New(`request header "TE" may only be "trailers" in HTTP/2`)
-	}
-	return nil
-}
-
-func http2new400Handler(err error) HandlerFunc {
-	return func(w ResponseWriter, r *Request) {
-		Error(w, err.Error(), StatusBadRequest)
-	}
-}
-
-// h1ServerKeepAlivesDisabled reports whether hs has its keep-alives
-// disabled. See comments on h1ServerShutdownChan above for why
-// the code is written this way.
-func http2h1ServerKeepAlivesDisabled(hs *Server) bool {
-	var x interface{} = hs
-	type I interface {
-		doKeepAlives() bool
-	}
-	if hs, ok := x.(I); ok {
-		return !hs.doKeepAlives()
-	}
-	return false
-}
-
-func (sc *http2serverConn) countError(name string, err error) error {
-	if sc == nil || sc.srv == nil {
-		return err
-	}
-	f := sc.srv.CountError
-	if f == nil {
-		return err
-	}
-	var typ string
-	var code http2ErrCode
-	switch e := err.(type) {
-	case http2ConnectionError:
-		typ = "conn"
-		code = http2ErrCode(e)
-	case http2StreamError:
-		typ = "stream"
-		code = http2ErrCode(e.Code)
-	default:
-		return err
-	}
-	codeStr := http2errCodeName[code]
-	if codeStr == "" {
-		codeStr = strconv.Itoa(int(code))
-	}
-	f(fmt.Sprintf("%s_%s_%s", typ, codeStr, name))
-	return err
-}
-
-const (
-	// transportDefaultConnFlow is how many connection-level flow control
-	// tokens we give the server at start-up, past the default 64k.
-	http2transportDefaultConnFlow = 1 << 30
-
-	// transportDefaultStreamFlow is how many stream-level flow
-	// control tokens we announce to the peer, and how many bytes
-	// we buffer per stream.
-	http2transportDefaultStreamFlow = 4 << 20
-
-	// transportDefaultStreamMinRefresh is the minimum number of bytes we'll send
-	// a stream-level WINDOW_UPDATE for at a time.
-	http2transportDefaultStreamMinRefresh = 4 << 10
-
-	http2defaultUserAgent = "Go-http-client/2.0"
-
-	// initialMaxConcurrentStreams is a connections maxConcurrentStreams until
-	// it's received servers initial SETTINGS frame, which corresponds with the
-	// spec's minimum recommended value.
-	http2initialMaxConcurrentStreams = 100
-
-	// defaultMaxConcurrentStreams is a connections default maxConcurrentStreams
-	// if the server doesn't include one in its initial SETTINGS frame.
-	http2defaultMaxConcurrentStreams = 1000
-)
-
-// Transport is an HTTP/2 Transport.
-//
-// A Transport internally caches connections to servers. It is safe
-// for concurrent use by multiple goroutines.
-type http2Transport struct {
-	// DialTLS specifies an optional dial function for creating
-	// TLS connections for requests.
-	//
-	// If DialTLS is nil, tls.Dial is used.
-	//
-	// If the returned net.Conn has a ConnectionState method like tls.Conn,
-	// it will be used to set http.Response.TLS.
-	DialTLS func(network, addr string, cfg *tls.Config) (net.Conn, error)
-
-	// TLSClientConfig specifies the TLS configuration to use with
-	// tls.Client. If nil, the default configuration is used.
-	TLSClientConfig *tls.Config
-
-	// ConnPool optionally specifies an alternate connection pool to use.
-	// If nil, the default is used.
-	ConnPool http2ClientConnPool
-
-	// DisableCompression, if true, prevents the Transport from
-	// requesting compression with an "Accept-Encoding: gzip"
-	// request header when the Request contains no existing
-	// Accept-Encoding value. If the Transport requests gzip on
-	// its own and gets a gzipped response, it's transparently
-	// decoded in the Response.Body. However, if the user
-	// explicitly requested gzip it is not automatically
-	// uncompressed.
-	DisableCompression bool
-
-	// AllowHTTP, if true, permits HTTP/2 requests using the insecure,
-	// plain-text "http" scheme. Note that this does not enable h2c support.
-	AllowHTTP bool
-
-	// MaxHeaderListSize is the http2 SETTINGS_MAX_HEADER_LIST_SIZE to
-	// send in the initial settings frame. It is how many bytes
-	// of response headers are allowed. Unlike the http2 spec, zero here
-	// means to use a default limit (currently 10MB). If you actually
-	// want to advertise an unlimited value to the peer, Transport
-	// interprets the highest possible value here (0xffffffff or 1<<32-1)
-	// to mean no limit.
-	MaxHeaderListSize uint32
-
-	// StrictMaxConcurrentStreams controls whether the server's
-	// SETTINGS_MAX_CONCURRENT_STREAMS should be respected
-	// globally. If false, new TCP connections are created to the
-	// server as needed to keep each under the per-connection
-	// SETTINGS_MAX_CONCURRENT_STREAMS limit. If true, the
-	// server's SETTINGS_MAX_CONCURRENT_STREAMS is interpreted as
-	// a global limit and callers of RoundTrip block when needed,
-	// waiting for their turn.
-	StrictMaxConcurrentStreams bool
-
-	// ReadIdleTimeout is the timeout after which a health check using ping
-	// frame will be carried out if no frame is received on the connection.
-	// Note that a ping response will is considered a received frame, so if
-	// there is no other traffic on the connection, the health check will
-	// be performed every ReadIdleTimeout interval.
-	// If zero, no health check is performed.
-	ReadIdleTimeout time.Duration
-
-	// PingTimeout is the timeout after which the connection will be closed
-	// if a response to Ping is not received.
-	// Defaults to 15s.
-	PingTimeout time.Duration
-
-	// WriteByteTimeout is the timeout after which the connection will be
-	// closed no data can be written to it. The timeout begins when data is
-	// available to write, and is extended whenever any bytes are written.
-	WriteByteTimeout time.Duration
-
-	// CountError, if non-nil, is called on HTTP/2 transport errors.
-	// It's intended to increment a metric for monitoring, such
-	// as an expvar or Prometheus metric.
-	// The errType consists of only ASCII word characters.
-	CountError func(errType string)
-
-	// t1, if non-nil, is the standard library Transport using
-	// this transport. Its settings are used (but not its
-	// RoundTrip method, etc).
-	t1 *Transport
-
-	connPoolOnce  sync.Once
-	connPoolOrDef http2ClientConnPool // non-nil version of ConnPool
-}
-
-func (t *http2Transport) maxHeaderListSize() uint32 {
-	if t.MaxHeaderListSize == 0 {
-		return 10 << 20
-	}
-	if t.MaxHeaderListSize == 0xffffffff {
-		return 0
-	}
-	return t.MaxHeaderListSize
-}
-
-func (t *http2Transport) disableCompression() bool {
-	return t.DisableCompression || (t.t1 != nil && t.t1.DisableCompression)
-}
-
-func (t *http2Transport) pingTimeout() time.Duration {
-	if t.PingTimeout == 0 {
-		return 15 * time.Second
-	}
-	return t.PingTimeout
-
-}
-
-// ConfigureTransport configures a net/http HTTP/1 Transport to use HTTP/2.
-// It returns an error if t1 has already been HTTP/2-enabled.
-//
-// Use ConfigureTransports instead to configure the HTTP/2 Transport.
-func http2ConfigureTransport(t1 *Transport) error {
-	_, err := http2ConfigureTransports(t1)
-	return err
-}
-
-// ConfigureTransports configures a net/http HTTP/1 Transport to use HTTP/2.
-// It returns a new HTTP/2 Transport for further configuration.
-// It returns an error if t1 has already been HTTP/2-enabled.
-func http2ConfigureTransports(t1 *Transport) (*http2Transport, error) {
-	return http2configureTransports(t1)
-}
-
-func http2configureTransports(t1 *Transport) (*http2Transport, error) {
-	connPool := new(http2clientConnPool)
-	t2 := &http2Transport{
-		ConnPool: http2noDialClientConnPool{connPool},
-		t1:       t1,
-	}
-	connPool.t = t2
-	if err := http2registerHTTPSProtocol(t1, http2noDialH2RoundTripper{t2}); err != nil {
-		return nil, err
-	}
-	if t1.TLSClientConfig == nil {
-		t1.TLSClientConfig = new(tls.Config)
-	}
-	if !http2strSliceContains(t1.TLSClientConfig.NextProtos, "h2") {
-		t1.TLSClientConfig.NextProtos = append([]string{"h2"}, t1.TLSClientConfig.NextProtos...)
-	}
-	if !http2strSliceContains(t1.TLSClientConfig.NextProtos, "http/1.1") {
-		t1.TLSClientConfig.NextProtos = append(t1.TLSClientConfig.NextProtos, "http/1.1")
-	}
-	upgradeFn := func(authority string, c *tls.Conn) RoundTripper {
-		addr := http2authorityAddr("https", authority)
-		if used, err := connPool.addConnIfNeeded(addr, t2, c); err != nil {
-			go c.Close()
-			return http2erringRoundTripper{err}
-		} else if !used {
-			// Turns out we don't need this c.
-			// For example, two goroutines made requests to the same host
-			// at the same time, both kicking off TCP dials. (since protocol
-			// was unknown)
-			go c.Close()
-		}
-		return t2
-	}
-	if m := t1.TLSNextProto; len(m) == 0 {
-		t1.TLSNextProto = map[string]func(string, *tls.Conn) RoundTripper{
-			"h2": upgradeFn,
-		}
-	} else {
-		m["h2"] = upgradeFn
-	}
-	return t2, nil
-}
-
-func (t *http2Transport) connPool() http2ClientConnPool {
-	t.connPoolOnce.Do(t.initConnPool)
-	return t.connPoolOrDef
-}
-
-func (t *http2Transport) initConnPool() {
-	if t.ConnPool != nil {
-		t.connPoolOrDef = t.ConnPool
-	} else {
-		t.connPoolOrDef = &http2clientConnPool{t: t}
-	}
-}
-
-// ClientConn is the state of a single HTTP/2 client connection to an
-// HTTP/2 server.
-type http2ClientConn struct {
-	t             *http2Transport
-	tconn         net.Conn             // usually *tls.Conn, except specialized impls
-	tlsState      *tls.ConnectionState // nil only for specialized impls
-	reused        uint32               // whether conn is being reused; atomic
-	singleUse     bool                 // whether being used for a single http.Request
-	getConnCalled bool                 // used by clientConnPool
-
-	// readLoop goroutine fields:
-	readerDone chan struct{} // closed on error
-	readerErr  error         // set before readerDone is closed
-
-	idleTimeout time.Duration // or 0 for never
-	idleTimer   *time.Timer
-
-	mu              sync.Mutex // guards following
-	cond            *sync.Cond // hold mu; broadcast on flow/closed changes
-	flow            http2flow  // our conn-level flow control quota (cs.flow is per stream)
-	inflow          http2flow  // peer's conn-level flow control
-	doNotReuse      bool       // whether conn is marked to not be reused for any future requests
-	closing         bool
-	closed          bool
-	seenSettings    bool                          // true if we've seen a settings frame, false otherwise
-	wantSettingsAck bool                          // we sent a SETTINGS frame and haven't heard back
-	goAway          *http2GoAwayFrame             // if non-nil, the GoAwayFrame we received
-	goAwayDebug     string                        // goAway frame's debug data, retained as a string
-	streams         map[uint32]*http2clientStream // client-initiated
-	streamsReserved int                           // incr by ReserveNewRequest; decr on RoundTrip
-	nextStreamID    uint32
-	pendingRequests int                       // requests blocked and waiting to be sent because len(streams) == maxConcurrentStreams
-	pings           map[[8]byte]chan struct{} // in flight ping data to notification channel
-	br              *bufio.Reader
-	lastActive      time.Time
-	lastIdle        time.Time // time last idle
-	// Settings from peer: (also guarded by wmu)
-	maxFrameSize          uint32
-	maxConcurrentStreams  uint32
-	peerMaxHeaderListSize uint64
-	initialWindowSize     uint32
-
-	// reqHeaderMu is a 1-element semaphore channel controlling access to sending new requests.
-	// Write to reqHeaderMu to lock it, read from it to unlock.
-	// Lock reqmu BEFORE mu or wmu.
-	reqHeaderMu chan struct{}
-
-	// wmu is held while writing.
-	// Acquire BEFORE mu when holding both, to avoid blocking mu on network writes.
-	// Only acquire both at the same time when changing peer settings.
-	wmu  sync.Mutex
-	bw   *bufio.Writer
-	fr   *http2Framer
-	werr error        // first write error that has occurred
-	hbuf bytes.Buffer // HPACK encoder writes into this
-	henc *hpack.Encoder
-}
-
-// clientStream is the state for a single HTTP/2 stream. One of these
-// is created for each Transport.RoundTrip call.
-type http2clientStream struct {
-	cc *http2ClientConn
-
-	// Fields of Request that we may access even after the response body is closed.
-	ctx       context.Context
-	reqCancel <-chan struct{}
-
-	trace         *httptrace.ClientTrace // or nil
-	ID            uint32
-	bufPipe       http2pipe // buffered pipe with the flow-controlled response payload
-	requestedGzip bool
-	isHead        bool
-
-	abortOnce sync.Once
-	abort     chan struct{} // closed to signal stream should end immediately
-	abortErr  error         // set if abort is closed
-
-	peerClosed chan struct{} // closed when the peer sends an END_STREAM flag
-	donec      chan struct{} // closed after the stream is in the closed state
-	on100      chan struct{} // buffered; written to if a 100 is received
-
-	respHeaderRecv chan struct{} // closed when headers are received
-	res            *Response     // set if respHeaderRecv is closed
-
-	flow        http2flow // guarded by cc.mu
-	inflow      http2flow // guarded by cc.mu
-	bytesRemain int64     // -1 means unknown; owned by transportResponseBody.Read
-	readErr     error     // sticky read error; owned by transportResponseBody.Read
-
-	reqBody              io.ReadCloser
-	reqBodyContentLength int64 // -1 means unknown
-	reqBodyClosed        bool  // body has been closed; guarded by cc.mu
-
-	// owned by writeRequest:
-	sentEndStream bool // sent an END_STREAM flag to the peer
-	sentHeaders   bool
-
-	// owned by clientConnReadLoop:
-	firstByte    bool  // got the first response byte
-	pastHeaders  bool  // got first MetaHeadersFrame (actual headers)
-	pastTrailers bool  // got optional second MetaHeadersFrame (trailers)
-	num1xx       uint8 // number of 1xx responses seen
-	readClosed   bool  // peer sent an END_STREAM flag
-	readAborted  bool  // read loop reset the stream
-
-	trailer    Header  // accumulated trailers
-	resTrailer *Header // client's Response.Trailer
-}
-
-var http2got1xxFuncForTests func(int, textproto.MIMEHeader) error
-
-// get1xxTraceFunc returns the value of request's httptrace.ClientTrace.Got1xxResponse func,
-// if any. It returns nil if not set or if the Go version is too old.
-func (cs *http2clientStream) get1xxTraceFunc() func(int, textproto.MIMEHeader) error {
-	if fn := http2got1xxFuncForTests; fn != nil {
-		return fn
-	}
-	return http2traceGot1xxResponseFunc(cs.trace)
-}
-
-func (cs *http2clientStream) abortStream(err error) {
-	cs.cc.mu.Lock()
-	defer cs.cc.mu.Unlock()
-	cs.abortStreamLocked(err)
-}
-
-func (cs *http2clientStream) abortStreamLocked(err error) {
-	cs.abortOnce.Do(func() {
-		cs.abortErr = err
-		close(cs.abort)
-	})
-	if cs.reqBody != nil && !cs.reqBodyClosed {
-		cs.reqBody.Close()
-		cs.reqBodyClosed = true
-	}
-	// TODO(dneil): Clean up tests where cs.cc.cond is nil.
-	if cs.cc.cond != nil {
-		// Wake up writeRequestBody if it is waiting on flow control.
-		cs.cc.cond.Broadcast()
-	}
-}
-
-func (cs *http2clientStream) abortRequestBodyWrite() {
-	cc := cs.cc
-	cc.mu.Lock()
-	defer cc.mu.Unlock()
-	if cs.reqBody != nil && !cs.reqBodyClosed {
-		cs.reqBody.Close()
-		cs.reqBodyClosed = true
-		cc.cond.Broadcast()
-	}
-}
-
-type http2stickyErrWriter struct {
-	conn    net.Conn
-	timeout time.Duration
-	err     *error
-}
-
-func (sew http2stickyErrWriter) Write(p []byte) (n int, err error) {
-	if *sew.err != nil {
-		return 0, *sew.err
-	}
-	for {
-		if sew.timeout != 0 {
-			sew.conn.SetWriteDeadline(time.Now().Add(sew.timeout))
-		}
-		nn, err := sew.conn.Write(p[n:])
-		n += nn
-		if n < len(p) && nn > 0 && errors.Is(err, os.ErrDeadlineExceeded) {
-			// Keep extending the deadline so long as we're making progress.
-			continue
-		}
-		if sew.timeout != 0 {
-			sew.conn.SetWriteDeadline(time.Time{})
-		}
-		*sew.err = err
-		return n, err
-	}
-}
-
-// noCachedConnError is the concrete type of ErrNoCachedConn, which
-// needs to be detected by net/http regardless of whether it's its
-// bundled version (in h2_bundle.go with a rewritten type name) or
-// from a user's x/net/http2. As such, as it has a unique method name
-// (IsHTTP2NoCachedConnError) that net/http sniffs for via func
-// isNoCachedConnError.
-type http2noCachedConnError struct{}
-
-func (http2noCachedConnError) IsHTTP2NoCachedConnError() {}
-
-func (http2noCachedConnError) Error() string { return "http2: no cached connection was available" }
-
-// isNoCachedConnError reports whether err is of type noCachedConnError
-// or its equivalent renamed type in net/http2's h2_bundle.go. Both types
-// may coexist in the same running program.
-func http2isNoCachedConnError(err error) bool {
-	_, ok := err.(interface{ IsHTTP2NoCachedConnError() })
-	return ok
-}
-
-var http2ErrNoCachedConn error = http2noCachedConnError{}
-
-// RoundTripOpt are options for the Transport.RoundTripOpt method.
-type http2RoundTripOpt struct {
-	// OnlyCachedConn controls whether RoundTripOpt may
-	// create a new TCP connection. If set true and
-	// no cached connection is available, RoundTripOpt
-	// will return ErrNoCachedConn.
-	OnlyCachedConn bool
-}
-
-func (t *http2Transport) RoundTrip(req *Request) (*Response, error) {
-	return t.RoundTripOpt(req, http2RoundTripOpt{})
-}
-
-// authorityAddr returns a given authority (a host/IP, or host:port / ip:port)
-// and returns a host:port. The port 443 is added if needed.
-func http2authorityAddr(scheme string, authority string) (addr string) {
-	host, port, err := net.SplitHostPort(authority)
-	if err != nil { // authority didn't have a port
-		port = "443"
-		if scheme == "http" {
-			port = "80"
-		}
-		host = authority
-	}
-	if a, err := idna.ToASCII(host); err == nil {
-		host = a
-	}
-	// IPv6 address literal, without a port:
-	if strings.HasPrefix(host, "[") && strings.HasSuffix(host, "]") {
-		return host + ":" + port
-	}
-	return net.JoinHostPort(host, port)
-}
-
-// RoundTripOpt is like RoundTrip, but takes options.
-func (t *http2Transport) RoundTripOpt(req *Request, opt http2RoundTripOpt) (*Response, error) {
-	if !(req.URL.Scheme == "https" || (req.URL.Scheme == "http" && t.AllowHTTP)) {
-		return nil, errors.New("http2: unsupported scheme")
-	}
-
-	addr := http2authorityAddr(req.URL.Scheme, req.URL.Host)
-	for retry := 0; ; retry++ {
-		cc, err := t.connPool().GetClientConn(req, addr)
-		if err != nil {
-			t.vlogf("http2: Transport failed to get client conn for %s: %v", addr, err)
-			return nil, err
-		}
-		reused := !atomic.CompareAndSwapUint32(&cc.reused, 0, 1)
-		http2traceGotConn(req, cc, reused)
-		res, err := cc.RoundTrip(req)
-		if err != nil && retry <= 6 {
-			if req, err = http2shouldRetryRequest(req, err); err == nil {
-				// After the first retry, do exponential backoff with 10% jitter.
-				if retry == 0 {
-					continue
-				}
-				backoff := float64(uint(1) << (uint(retry) - 1))
-				backoff += backoff * (0.1 * mathrand.Float64())
-				select {
-				case <-time.After(time.Second * time.Duration(backoff)):
-					continue
-				case <-req.Context().Done():
-					err = req.Context().Err()
-				}
-			}
-		}
-		if err != nil {
-			t.vlogf("RoundTrip failure: %v", err)
-			return nil, err
-		}
-		return res, nil
-	}
-}
-
-// CloseIdleConnections closes any connections which were previously
-// connected from previous requests but are now sitting idle.
-// It does not interrupt any connections currently in use.
-func (t *http2Transport) CloseIdleConnections() {
-	if cp, ok := t.connPool().(http2clientConnPoolIdleCloser); ok {
-		cp.closeIdleConnections()
-	}
-}
-
-var (
-	http2errClientConnClosed    = errors.New("http2: client conn is closed")
-	http2errClientConnUnusable  = errors.New("http2: client conn not usable")
-	http2errClientConnGotGoAway = errors.New("http2: Transport received Server's graceful shutdown GOAWAY")
-)
-
-// shouldRetryRequest is called by RoundTrip when a request fails to get
-// response headers. It is always called with a non-nil error.
-// It returns either a request to retry (either the same request, or a
-// modified clone), or an error if the request can't be replayed.
-func http2shouldRetryRequest(req *Request, err error) (*Request, error) {
-	if !http2canRetryError(err) {
-		return nil, err
-	}
-	// If the Body is nil (or http.NoBody), it's safe to reuse
-	// this request and its Body.
-	if req.Body == nil || req.Body == NoBody {
-		return req, nil
-	}
-
-	// If the request body can be reset back to its original
-	// state via the optional req.GetBody, do that.
-	if req.GetBody != nil {
-		body, err := req.GetBody()
-		if err != nil {
-			return nil, err
-		}
-		newReq := *req
-		newReq.Body = body
-		return &newReq, nil
-	}
-
-	// The Request.Body can't reset back to the beginning, but we
-	// don't seem to have started to read from it yet, so reuse
-	// the request directly.
-	if err == http2errClientConnUnusable {
-		return req, nil
-	}
-
-	return nil, fmt.Errorf("http2: Transport: cannot retry err [%v] after Request.Body was written; define Request.GetBody to avoid this error", err)
-}
-
-func http2canRetryError(err error) bool {
-	if err == http2errClientConnUnusable || err == http2errClientConnGotGoAway {
-		return true
-	}
-	if se, ok := err.(http2StreamError); ok {
-		if se.Code == http2ErrCodeProtocol && se.Cause == http2errFromPeer {
-			// See golang/go#47635, golang/go#42777
-			return true
-		}
-		return se.Code == http2ErrCodeRefusedStream
-	}
-	return false
-}
-
-func (t *http2Transport) dialClientConn(ctx context.Context, addr string, singleUse bool) (*http2ClientConn, error) {
-	host, _, err := net.SplitHostPort(addr)
-	if err != nil {
-		return nil, err
-	}
-	tconn, err := t.dialTLS(ctx)("tcp", addr, t.newTLSConfig(host))
-	if err != nil {
-		return nil, err
-	}
-	return t.newClientConn(tconn, singleUse)
-}
-
-func (t *http2Transport) newTLSConfig(host string) *tls.Config {
-	cfg := new(tls.Config)
-	if t.TLSClientConfig != nil {
-		*cfg = *t.TLSClientConfig.Clone()
-	}
-	if !http2strSliceContains(cfg.NextProtos, http2NextProtoTLS) {
-		cfg.NextProtos = append([]string{http2NextProtoTLS}, cfg.NextProtos...)
-	}
-	if cfg.ServerName == "" {
-		cfg.ServerName = host
-	}
-	return cfg
-}
-
-func (t *http2Transport) dialTLS(ctx context.Context) func(string, string, *tls.Config) (net.Conn, error) {
-	if t.DialTLS != nil {
-		return t.DialTLS
-	}
-	return func(network, addr string, cfg *tls.Config) (net.Conn, error) {
-		tlsCn, err := t.dialTLSWithContext(ctx, network, addr, cfg)
-		if err != nil {
-			return nil, err
-		}
-		state := tlsCn.ConnectionState()
-		if p := state.NegotiatedProtocol; p != http2NextProtoTLS {
-			return nil, fmt.Errorf("http2: unexpected ALPN protocol %q; want %q", p, http2NextProtoTLS)
-		}
-		if !state.NegotiatedProtocolIsMutual {
-			return nil, errors.New("http2: could not negotiate protocol mutually")
-		}
-		return tlsCn, nil
-	}
-}
-
-// disableKeepAlives reports whether connections should be closed as
-// soon as possible after handling the first request.
-func (t *http2Transport) disableKeepAlives() bool {
-	return t.t1 != nil && t.t1.DisableKeepAlives
-}
-
-func (t *http2Transport) expectContinueTimeout() time.Duration {
-	if t.t1 == nil {
-		return 0
-	}
-	return t.t1.ExpectContinueTimeout
-}
-
-func (t *http2Transport) NewClientConn(c net.Conn) (*http2ClientConn, error) {
-	return t.newClientConn(c, t.disableKeepAlives())
-}
-
-func (t *http2Transport) newClientConn(c net.Conn, singleUse bool) (*http2ClientConn, error) {
-	cc := &http2ClientConn{
-		t:                     t,
-		tconn:                 c,
-		readerDone:            make(chan struct{}),
-		nextStreamID:          1,
-		maxFrameSize:          16 << 10,                         // spec default
-		initialWindowSize:     65535,                            // spec default
-		maxConcurrentStreams:  http2initialMaxConcurrentStreams, // "infinite", per spec. Use a smaller value until we have received server settings.
-		peerMaxHeaderListSize: 0xffffffffffffffff,               // "infinite", per spec. Use 2^64-1 instead.
-		streams:               make(map[uint32]*http2clientStream),
-		singleUse:             singleUse,
-		wantSettingsAck:       true,
-		pings:                 make(map[[8]byte]chan struct{}),
-		reqHeaderMu:           make(chan struct{}, 1),
-	}
-	if d := t.idleConnTimeout(); d != 0 {
-		cc.idleTimeout = d
-		cc.idleTimer = time.AfterFunc(d, cc.onIdleTimeout)
-	}
-	if http2VerboseLogs {
-		t.vlogf("http2: Transport creating client conn %p to %v", cc, c.RemoteAddr())
-	}
-
-	cc.cond = sync.NewCond(&cc.mu)
-	cc.flow.add(int32(http2initialWindowSize))
-
-	// TODO: adjust this writer size to account for frame size +
-	// MTU + crypto/tls record padding.
-	cc.bw = bufio.NewWriter(http2stickyErrWriter{
-		conn:    c,
-		timeout: t.WriteByteTimeout,
-		err:     &cc.werr,
-	})
-	cc.br = bufio.NewReader(c)
-	cc.fr = http2NewFramer(cc.bw, cc.br)
-	if t.CountError != nil {
-		cc.fr.countError = t.CountError
-	}
-	cc.fr.ReadMetaHeaders = hpack.NewDecoder(http2initialHeaderTableSize, nil)
-	cc.fr.MaxHeaderListSize = t.maxHeaderListSize()
-
-	// TODO: SetMaxDynamicTableSize, SetMaxDynamicTableSizeLimit on
-	// henc in response to SETTINGS frames?
-	cc.henc = hpack.NewEncoder(&cc.hbuf)
-
-	if t.AllowHTTP {
-		cc.nextStreamID = 3
-	}
-
-	if cs, ok := c.(http2connectionStater); ok {
-		state := cs.ConnectionState()
-		cc.tlsState = &state
-	}
-
-	initialSettings := []http2Setting{
-		{ID: http2SettingEnablePush, Val: 0},
-		{ID: http2SettingInitialWindowSize, Val: http2transportDefaultStreamFlow},
-	}
-	if max := t.maxHeaderListSize(); max != 0 {
-		initialSettings = append(initialSettings, http2Setting{ID: http2SettingMaxHeaderListSize, Val: max})
-	}
-
-	cc.bw.Write(http2clientPreface)
-	cc.fr.WriteSettings(initialSettings...)
-	cc.fr.WriteWindowUpdate(0, http2transportDefaultConnFlow)
-	cc.inflow.add(http2transportDefaultConnFlow + http2initialWindowSize)
-	cc.bw.Flush()
-	if cc.werr != nil {
-		cc.Close()
-		return nil, cc.werr
-	}
-
-	go cc.readLoop()
-	return cc, nil
-}
-
-func (cc *http2ClientConn) healthCheck() {
-	pingTimeout := cc.t.pingTimeout()
-	// We don't need to periodically ping in the health check, because the readLoop of ClientConn will
-	// trigger the healthCheck again if there is no frame received.
-	ctx, cancel := context.WithTimeout(context.Background(), pingTimeout)
-	defer cancel()
-	err := cc.Ping(ctx)
-	if err != nil {
-		cc.closeForLostPing()
-		cc.t.connPool().MarkDead(cc)
-		return
-	}
-}
-
-// SetDoNotReuse marks cc as not reusable for future HTTP requests.
-func (cc *http2ClientConn) SetDoNotReuse() {
-	cc.mu.Lock()
-	defer cc.mu.Unlock()
-	cc.doNotReuse = true
-}
-
-func (cc *http2ClientConn) setGoAway(f *http2GoAwayFrame) {
-	cc.mu.Lock()
-	defer cc.mu.Unlock()
-
-	old := cc.goAway
-	cc.goAway = f
-
-	// Merge the previous and current GoAway error frames.
-	if cc.goAwayDebug == "" {
-		cc.goAwayDebug = string(f.DebugData())
-	}
-	if old != nil && old.ErrCode != http2ErrCodeNo {
-		cc.goAway.ErrCode = old.ErrCode
-	}
-	last := f.LastStreamID
-	for streamID, cs := range cc.streams {
-		if streamID > last {
-			cs.abortStreamLocked(http2errClientConnGotGoAway)
-		}
-	}
-}
-
-// CanTakeNewRequest reports whether the connection can take a new request,
-// meaning it has not been closed or received or sent a GOAWAY.
-//
-// If the caller is going to immediately make a new request on this
-// connection, use ReserveNewRequest instead.
-func (cc *http2ClientConn) CanTakeNewRequest() bool {
-	cc.mu.Lock()
-	defer cc.mu.Unlock()
-	return cc.canTakeNewRequestLocked()
-}
-
-// ReserveNewRequest is like CanTakeNewRequest but also reserves a
-// concurrent stream in cc. The reservation is decremented on the
-// next call to RoundTrip.
-func (cc *http2ClientConn) ReserveNewRequest() bool {
-	cc.mu.Lock()
-	defer cc.mu.Unlock()
-	if st := cc.idleStateLocked(); !st.canTakeNewRequest {
-		return false
-	}
-	cc.streamsReserved++
-	return true
-}
-
-// ClientConnState describes the state of a ClientConn.
-type http2ClientConnState struct {
-	// Closed is whether the connection is closed.
-	Closed bool
-
-	// Closing is whether the connection is in the process of
-	// closing. It may be closing due to shutdown, being a
-	// single-use connection, being marked as DoNotReuse, or
-	// having received a GOAWAY frame.
-	Closing bool
-
-	// StreamsActive is how many streams are active.
-	StreamsActive int
-
-	// StreamsReserved is how many streams have been reserved via
-	// ClientConn.ReserveNewRequest.
-	StreamsReserved int
-
-	// StreamsPending is how many requests have been sent in excess
-	// of the peer's advertised MaxConcurrentStreams setting and
-	// are waiting for other streams to complete.
-	StreamsPending int
-
-	// MaxConcurrentStreams is how many concurrent streams the
-	// peer advertised as acceptable. Zero means no SETTINGS
-	// frame has been received yet.
-	MaxConcurrentStreams uint32
-
-	// LastIdle, if non-zero, is when the connection last
-	// transitioned to idle state.
-	LastIdle time.Time
-}
-
-// State returns a snapshot of cc's state.
-func (cc *http2ClientConn) State() http2ClientConnState {
-	cc.wmu.Lock()
-	maxConcurrent := cc.maxConcurrentStreams
-	if !cc.seenSettings {
-		maxConcurrent = 0
-	}
-	cc.wmu.Unlock()
-
-	cc.mu.Lock()
-	defer cc.mu.Unlock()
-	return http2ClientConnState{
-		Closed:               cc.closed,
-		Closing:              cc.closing || cc.singleUse || cc.doNotReuse || cc.goAway != nil,
-		StreamsActive:        len(cc.streams),
-		StreamsReserved:      cc.streamsReserved,
-		StreamsPending:       cc.pendingRequests,
-		LastIdle:             cc.lastIdle,
-		MaxConcurrentStreams: maxConcurrent,
-	}
-}
-
-// clientConnIdleState describes the suitability of a client
-// connection to initiate a new RoundTrip request.
-type http2clientConnIdleState struct {
-	canTakeNewRequest bool
-}
-
-func (cc *http2ClientConn) idleState() http2clientConnIdleState {
-	cc.mu.Lock()
-	defer cc.mu.Unlock()
-	return cc.idleStateLocked()
-}
-
-func (cc *http2ClientConn) idleStateLocked() (st http2clientConnIdleState) {
-	if cc.singleUse && cc.nextStreamID > 1 {
-		return
-	}
-	var maxConcurrentOkay bool
-	if cc.t.StrictMaxConcurrentStreams {
-		// We'll tell the caller we can take a new request to
-		// prevent the caller from dialing a new TCP
-		// connection, but then we'll block later before
-		// writing it.
-		maxConcurrentOkay = true
-	} else {
-		maxConcurrentOkay = int64(len(cc.streams)+cc.streamsReserved+1) <= int64(cc.maxConcurrentStreams)
-	}
-
-	st.canTakeNewRequest = cc.goAway == nil && !cc.closed && !cc.closing && maxConcurrentOkay &&
-		!cc.doNotReuse &&
-		int64(cc.nextStreamID)+2*int64(cc.pendingRequests) < math.MaxInt32 &&
-		!cc.tooIdleLocked()
-	return
-}
-
-func (cc *http2ClientConn) canTakeNewRequestLocked() bool {
-	st := cc.idleStateLocked()
-	return st.canTakeNewRequest
-}
-
-// tooIdleLocked reports whether this connection has been been sitting idle
-// for too much wall time.
-func (cc *http2ClientConn) tooIdleLocked() bool {
-	// The Round(0) strips the monontonic clock reading so the
-	// times are compared based on their wall time. We don't want
-	// to reuse a connection that's been sitting idle during
-	// VM/laptop suspend if monotonic time was also frozen.
-	return cc.idleTimeout != 0 && !cc.lastIdle.IsZero() && time.Since(cc.lastIdle.Round(0)) > cc.idleTimeout
-}
-
-// onIdleTimeout is called from a time.AfterFunc goroutine. It will
-// only be called when we're idle, but because we're coming from a new
-// goroutine, there could be a new request coming in at the same time,
-// so this simply calls the synchronized closeIfIdle to shut down this
-// connection. The timer could just call closeIfIdle, but this is more
-// clear.
-func (cc *http2ClientConn) onIdleTimeout() {
-	cc.closeIfIdle()
-}
-
-func (cc *http2ClientConn) closeIfIdle() {
-	cc.mu.Lock()
-	if len(cc.streams) > 0 || cc.streamsReserved > 0 {
-		cc.mu.Unlock()
-		return
-	}
-	cc.closed = true
-	nextID := cc.nextStreamID
-	// TODO: do clients send GOAWAY too? maybe? Just Close:
-	cc.mu.Unlock()
-
-	if http2VerboseLogs {
-		cc.vlogf("http2: Transport closing idle conn %p (forSingleUse=%v, maxStream=%v)", cc, cc.singleUse, nextID-2)
-	}
-	cc.tconn.Close()
-}
-
-func (cc *http2ClientConn) isDoNotReuseAndIdle() bool {
-	cc.mu.Lock()
-	defer cc.mu.Unlock()
-	return cc.doNotReuse && len(cc.streams) == 0
-}
-
-var http2shutdownEnterWaitStateHook = func() {}
-
-// Shutdown gracefully closes the client connection, waiting for running streams to complete.
-func (cc *http2ClientConn) Shutdown(ctx context.Context) error {
-	if err := cc.sendGoAway(); err != nil {
-		return err
-	}
-	// Wait for all in-flight streams to complete or connection to close
-	done := make(chan error, 1)
-	cancelled := false // guarded by cc.mu
-	go func() {
-		cc.mu.Lock()
-		defer cc.mu.Unlock()
-		for {
-			if len(cc.streams) == 0 || cc.closed {
-				cc.closed = true
-				done <- cc.tconn.Close()
-				break
-			}
-			if cancelled {
-				break
-			}
-			cc.cond.Wait()
-		}
-	}()
-	http2shutdownEnterWaitStateHook()
-	select {
-	case err := <-done:
-		return err
-	case <-ctx.Done():
-		cc.mu.Lock()
-		// Free the goroutine above
-		cancelled = true
-		cc.cond.Broadcast()
-		cc.mu.Unlock()
-		return ctx.Err()
-	}
-}
-
-func (cc *http2ClientConn) sendGoAway() error {
-	cc.mu.Lock()
-	closing := cc.closing
-	cc.closing = true
-	maxStreamID := cc.nextStreamID
-	cc.mu.Unlock()
-	if closing {
-		// GOAWAY sent already
-		return nil
-	}
-
-	cc.wmu.Lock()
-	defer cc.wmu.Unlock()
-	// Send a graceful shutdown frame to server
-	if err := cc.fr.WriteGoAway(maxStreamID, http2ErrCodeNo, nil); err != nil {
-		return err
-	}
-	if err := cc.bw.Flush(); err != nil {
-		return err
-	}
-	// Prevent new requests
-	return nil
-}
-
-// closes the client connection immediately. In-flight requests are interrupted.
-// err is sent to streams.
-func (cc *http2ClientConn) closeForError(err error) error {
-	cc.mu.Lock()
-	cc.closed = true
-	for _, cs := range cc.streams {
-		cs.abortStreamLocked(err)
-	}
-	defer cc.cond.Broadcast()
-	defer cc.mu.Unlock()
-	return cc.tconn.Close()
-}
-
-// Close closes the client connection immediately.
-//
-// In-flight requests are interrupted. For a graceful shutdown, use Shutdown instead.
-func (cc *http2ClientConn) Close() error {
-	err := errors.New("http2: client connection force closed via ClientConn.Close")
-	return cc.closeForError(err)
-}
-
-// closes the client connection immediately. In-flight requests are interrupted.
-func (cc *http2ClientConn) closeForLostPing() error {
-	err := errors.New("http2: client connection lost")
-	if f := cc.t.CountError; f != nil {
-		f("conn_close_lost_ping")
-	}
-	return cc.closeForError(err)
-}
-
-// errRequestCanceled is a copy of net/http's errRequestCanceled because it's not
-// exported. At least they'll be DeepEqual for h1-vs-h2 comparisons tests.
-var http2errRequestCanceled = errors.New("net/http: request canceled")
-
-func http2commaSeparatedTrailers(req *Request) (string, error) {
-	keys := make([]string, 0, len(req.Trailer))
-	for k := range req.Trailer {
-		k = CanonicalHeaderKey(k)
-		switch k {
-		case "Transfer-Encoding", "Trailer", "Content-Length":
-			return "", fmt.Errorf("invalid Trailer key %q", k)
-		}
-		keys = append(keys, k)
-	}
-	if len(keys) > 0 {
-		sort.Strings(keys)
-		return strings.Join(keys, ","), nil
-	}
-	return "", nil
-}
-
-func (cc *http2ClientConn) responseHeaderTimeout() time.Duration {
-	if cc.t.t1 != nil {
-		return cc.t.t1.ResponseHeaderTimeout
-	}
-	// No way to do this (yet?) with just an http2.Transport. Probably
-	// no need. Request.Cancel this is the new way. We only need to support
-	// this for compatibility with the old http.Transport fields when
-	// we're doing transparent http2.
-	return 0
-}
-
-// checkConnHeaders checks whether req has any invalid connection-level headers.
-// per RFC 7540 section 8.1.2.2: Connection-Specific Header Fields.
-// Certain headers are special-cased as okay but not transmitted later.
-func http2checkConnHeaders(req *Request) error {
-	if v := req.Header.Get("Upgrade"); v != "" {
-		return fmt.Errorf("http2: invalid Upgrade request header: %q", req.Header["Upgrade"])
-	}
-	if vv := req.Header["Transfer-Encoding"]; len(vv) > 0 && (len(vv) > 1 || vv[0] != "" && vv[0] != "chunked") {
-		return fmt.Errorf("http2: invalid Transfer-Encoding request header: %q", vv)
-	}
-	if vv := req.Header["Connection"]; len(vv) > 0 && (len(vv) > 1 || vv[0] != "" && !http2asciiEqualFold(vv[0], "close") && !http2asciiEqualFold(vv[0], "keep-alive")) {
-		return fmt.Errorf("http2: invalid Connection request header: %q", vv)
-	}
-	return nil
-}
-
-// actualContentLength returns a sanitized version of
-// req.ContentLength, where 0 actually means zero (not unknown) and -1
-// means unknown.
-func http2actualContentLength(req *Request) int64 {
-	if req.Body == nil || req.Body == NoBody {
-		return 0
-	}
-	if req.ContentLength != 0 {
-		return req.ContentLength
-	}
-	return -1
-}
-
-func (cc *http2ClientConn) decrStreamReservations() {
-	cc.mu.Lock()
-	defer cc.mu.Unlock()
-	cc.decrStreamReservationsLocked()
-}
-
-func (cc *http2ClientConn) decrStreamReservationsLocked() {
-	if cc.streamsReserved > 0 {
-		cc.streamsReserved--
-	}
-}
-
-func (cc *http2ClientConn) RoundTrip(req *Request) (*Response, error) {
-	ctx := req.Context()
-	cs := &http2clientStream{
-		cc:                   cc,
-		ctx:                  ctx,
-		reqCancel:            req.Cancel,
-		isHead:               req.Method == "HEAD",
-		reqBody:              req.Body,
-		reqBodyContentLength: http2actualContentLength(req),
-		trace:                httptrace.ContextClientTrace(ctx),
-		peerClosed:           make(chan struct{}),
-		abort:                make(chan struct{}),
-		respHeaderRecv:       make(chan struct{}),
-		donec:                make(chan struct{}),
-	}
-	go cs.doRequest(req)
-
-	waitDone := func() error {
-		select {
-		case <-cs.donec:
-			return nil
-		case <-ctx.Done():
-			return ctx.Err()
-		case <-cs.reqCancel:
-			return http2errRequestCanceled
-		}
-	}
-
-	handleResponseHeaders := func() (*Response, error) {
-		res := cs.res
-		if res.StatusCode > 299 {
-			// On error or status code 3xx, 4xx, 5xx, etc abort any
-			// ongoing write, assuming that the server doesn't care
-			// about our request body. If the server replied with 1xx or
-			// 2xx, however, then assume the server DOES potentially
-			// want our body (e.g. full-duplex streaming:
-			// golang.org/issue/13444). If it turns out the server
-			// doesn't, they'll RST_STREAM us soon enough. This is a
-			// heuristic to avoid adding knobs to Transport. Hopefully
-			// we can keep it.
-			cs.abortRequestBodyWrite()
-		}
-		res.Request = req
-		res.TLS = cc.tlsState
-		if res.Body == http2noBody && http2actualContentLength(req) == 0 {
-			// If there isn't a request or response body still being
-			// written, then wait for the stream to be closed before
-			// RoundTrip returns.
-			if err := waitDone(); err != nil {
-				return nil, err
-			}
-		}
-		return res, nil
-	}
-
-	for {
-		select {
-		case <-cs.respHeaderRecv:
-			return handleResponseHeaders()
-		case <-cs.abort:
-			select {
-			case <-cs.respHeaderRecv:
-				// If both cs.respHeaderRecv and cs.abort are signaling,
-				// pick respHeaderRecv. The server probably wrote the
-				// response and immediately reset the stream.
-				// golang.org/issue/49645
-				return handleResponseHeaders()
-			default:
-				waitDone()
-				return nil, cs.abortErr
-			}
-		case <-ctx.Done():
-			err := ctx.Err()
-			cs.abortStream(err)
-			return nil, err
-		case <-cs.reqCancel:
-			cs.abortStream(http2errRequestCanceled)
-			return nil, http2errRequestCanceled
-		}
-	}
-}
-
-// doRequest runs for the duration of the request lifetime.
-//
-// It sends the request and performs post-request cleanup (closing Request.Body, etc.).
-func (cs *http2clientStream) doRequest(req *Request) {
-	err := cs.writeRequest(req)
-	cs.cleanupWriteRequest(err)
-}
-
-// writeRequest sends a request.
-//
-// It returns nil after the request is written, the response read,
-// and the request stream is half-closed by the peer.
-//
-// It returns non-nil if the request ends otherwise.
-// If the returned error is StreamError, the error Code may be used in resetting the stream.
-func (cs *http2clientStream) writeRequest(req *Request) (err error) {
-	cc := cs.cc
-	ctx := cs.ctx
-
-	if err := http2checkConnHeaders(req); err != nil {
-		return err
-	}
-
-	// Acquire the new-request lock by writing to reqHeaderMu.
-	// This lock guards the critical section covering allocating a new stream ID
-	// (requires mu) and creating the stream (requires wmu).
-	if cc.reqHeaderMu == nil {
-		panic("RoundTrip on uninitialized ClientConn") // for tests
-	}
-	select {
-	case cc.reqHeaderMu <- struct{}{}:
-	case <-cs.reqCancel:
-		return http2errRequestCanceled
-	case <-ctx.Done():
-		return ctx.Err()
-	}
-
-	cc.mu.Lock()
-	if cc.idleTimer != nil {
-		cc.idleTimer.Stop()
-	}
-	cc.decrStreamReservationsLocked()
-	if err := cc.awaitOpenSlotForStreamLocked(cs); err != nil {
-		cc.mu.Unlock()
-		<-cc.reqHeaderMu
-		return err
-	}
-	cc.addStreamLocked(cs) // assigns stream ID
-	if http2isConnectionCloseRequest(req) {
-		cc.doNotReuse = true
-	}
-	cc.mu.Unlock()
-
-	// TODO(bradfitz): this is a copy of the logic in net/http. Unify somewhere?
-	if !cc.t.disableCompression() &&
-		req.Header.Get("Accept-Encoding") == "" &&
-		req.Header.Get("Range") == "" &&
-		!cs.isHead {
-		// Request gzip only, not deflate. Deflate is ambiguous and
-		// not as universally supported anyway.
-		// See: https://zlib.net/zlib_faq.html#faq39
-		//
-		// Note that we don't request this for HEAD requests,
-		// due to a bug in nginx:
-		//   http://trac.nginx.org/nginx/ticket/358
-		//   https://golang.org/issue/5522
-		//
-		// We don't request gzip if the request is for a range, since
-		// auto-decoding a portion of a gzipped document will just fail
-		// anyway. See https://golang.org/issue/8923
-		cs.requestedGzip = true
-	}
-
-	continueTimeout := cc.t.expectContinueTimeout()
-	if continueTimeout != 0 {
-		if !httpguts.HeaderValuesContainsToken(req.Header["Expect"], "100-continue") {
-			continueTimeout = 0
-		} else {
-			cs.on100 = make(chan struct{}, 1)
-		}
-	}
-
-	// Past this point (where we send request headers), it is possible for
-	// RoundTrip to return successfully. Since the RoundTrip contract permits
-	// the caller to "mutate or reuse" the Request after closing the Response's Body,
-	// we must take care when referencing the Request from here on.
-	err = cs.encodeAndWriteHeaders(req)
-	<-cc.reqHeaderMu
-	if err != nil {
-		return err
-	}
-
-	hasBody := cs.reqBodyContentLength != 0
-	if !hasBody {
-		cs.sentEndStream = true
-	} else {
-		if continueTimeout != 0 {
-			http2traceWait100Continue(cs.trace)
-			timer := time.NewTimer(continueTimeout)
-			select {
-			case <-timer.C:
-				err = nil
-			case <-cs.on100:
-				err = nil
-			case <-cs.abort:
-				err = cs.abortErr
-			case <-ctx.Done():
-				err = ctx.Err()
-			case <-cs.reqCancel:
-				err = http2errRequestCanceled
-			}
-			timer.Stop()
-			if err != nil {
-				http2traceWroteRequest(cs.trace, err)
-				return err
-			}
-		}
-
-		if err = cs.writeRequestBody(req); err != nil {
-			if err != http2errStopReqBodyWrite {
-				http2traceWroteRequest(cs.trace, err)
-				return err
-			}
-		} else {
-			cs.sentEndStream = true
-		}
-	}
-
-	http2traceWroteRequest(cs.trace, err)
-
-	var respHeaderTimer <-chan time.Time
-	var respHeaderRecv chan struct{}
-	if d := cc.responseHeaderTimeout(); d != 0 {
-		timer := time.NewTimer(d)
-		defer timer.Stop()
-		respHeaderTimer = timer.C
-		respHeaderRecv = cs.respHeaderRecv
-	}
-	// Wait until the peer half-closes its end of the stream,
-	// or until the request is aborted (via context, error, or otherwise),
-	// whichever comes first.
-	for {
-		select {
-		case <-cs.peerClosed:
-			return nil
-		case <-respHeaderTimer:
-			return http2errTimeout
-		case <-respHeaderRecv:
-			respHeaderRecv = nil
-			respHeaderTimer = nil // keep waiting for END_STREAM
-		case <-cs.abort:
-			return cs.abortErr
-		case <-ctx.Done():
-			return ctx.Err()
-		case <-cs.reqCancel:
-			return http2errRequestCanceled
-		}
-	}
-}
-
-func (cs *http2clientStream) encodeAndWriteHeaders(req *Request) error {
-	cc := cs.cc
-	ctx := cs.ctx
-
-	cc.wmu.Lock()
-	defer cc.wmu.Unlock()
-
-	// If the request was canceled while waiting for cc.mu, just quit.
-	select {
-	case <-cs.abort:
-		return cs.abortErr
-	case <-ctx.Done():
-		return ctx.Err()
-	case <-cs.reqCancel:
-		return http2errRequestCanceled
-	default:
-	}
-
-	// Encode headers.
-	//
-	// we send: HEADERS{1}, CONTINUATION{0,} + DATA{0,} (DATA is
-	// sent by writeRequestBody below, along with any Trailers,
-	// again in form HEADERS{1}, CONTINUATION{0,})
-	trailers, err := http2commaSeparatedTrailers(req)
-	if err != nil {
-		return err
-	}
-	hasTrailers := trailers != ""
-	contentLen := http2actualContentLength(req)
-	hasBody := contentLen != 0
-	hdrs, err := cc.encodeHeaders(req, cs.requestedGzip, trailers, contentLen)
-	if err != nil {
-		return err
-	}
-
-	// Write the request.
-	endStream := !hasBody && !hasTrailers
-	cs.sentHeaders = true
-	err = cc.writeHeaders(cs.ID, endStream, int(cc.maxFrameSize), hdrs)
-	http2traceWroteHeaders(cs.trace)
-	return err
-}
-
-// cleanupWriteRequest performs post-request tasks.
-//
-// If err (the result of writeRequest) is non-nil and the stream is not closed,
-// cleanupWriteRequest will send a reset to the peer.
-func (cs *http2clientStream) cleanupWriteRequest(err error) {
-	cc := cs.cc
-
-	if cs.ID == 0 {
-		// We were canceled before creating the stream, so return our reservation.
-		cc.decrStreamReservations()
-	}
-
-	// TODO: write h12Compare test showing whether
-	// Request.Body is closed by the Transport,
-	// and in multiple cases: server replies <=299 and >299
-	// while still writing request body
-	cc.mu.Lock()
-	bodyClosed := cs.reqBodyClosed
-	cs.reqBodyClosed = true
-	cc.mu.Unlock()
-	if !bodyClosed && cs.reqBody != nil {
-		cs.reqBody.Close()
-	}
-
-	if err != nil && cs.sentEndStream {
-		// If the connection is closed immediately after the response is read,
-		// we may be aborted before finishing up here. If the stream was closed
-		// cleanly on both sides, there is no error.
-		select {
-		case <-cs.peerClosed:
-			err = nil
-		default:
-		}
-	}
-	if err != nil {
-		cs.abortStream(err) // possibly redundant, but harmless
-		if cs.sentHeaders {
-			if se, ok := err.(http2StreamError); ok {
-				if se.Cause != http2errFromPeer {
-					cc.writeStreamReset(cs.ID, se.Code, err)
-				}
-			} else {
-				cc.writeStreamReset(cs.ID, http2ErrCodeCancel, err)
-			}
-		}
-		cs.bufPipe.CloseWithError(err) // no-op if already closed
-	} else {
-		if cs.sentHeaders && !cs.sentEndStream {
-			cc.writeStreamReset(cs.ID, http2ErrCodeNo, nil)
-		}
-		cs.bufPipe.CloseWithError(http2errRequestCanceled)
-	}
-	if cs.ID != 0 {
-		cc.forgetStreamID(cs.ID)
-	}
-
-	cc.wmu.Lock()
-	werr := cc.werr
-	cc.wmu.Unlock()
-	if werr != nil {
-		cc.Close()
-	}
-
-	close(cs.donec)
-}
-
-// awaitOpenSlotForStream waits until len(streams) < maxConcurrentStreams.
-// Must hold cc.mu.
-func (cc *http2ClientConn) awaitOpenSlotForStreamLocked(cs *http2clientStream) error {
-	for {
-		cc.lastActive = time.Now()
-		if cc.closed || !cc.canTakeNewRequestLocked() {
-			return http2errClientConnUnusable
-		}
-		cc.lastIdle = time.Time{}
-		if int64(len(cc.streams)) < int64(cc.maxConcurrentStreams) {
-			return nil
-		}
-		cc.pendingRequests++
-		cc.cond.Wait()
-		cc.pendingRequests--
-		select {
-		case <-cs.abort:
-			return cs.abortErr
-		default:
-		}
-	}
-}
-
-// requires cc.wmu be held
-func (cc *http2ClientConn) writeHeaders(streamID uint32, endStream bool, maxFrameSize int, hdrs []byte) error {
-	first := true // first frame written (HEADERS is first, then CONTINUATION)
-	for len(hdrs) > 0 && cc.werr == nil {
-		chunk := hdrs
-		if len(chunk) > maxFrameSize {
-			chunk = chunk[:maxFrameSize]
-		}
-		hdrs = hdrs[len(chunk):]
-		endHeaders := len(hdrs) == 0
-		if first {
-			cc.fr.WriteHeaders(http2HeadersFrameParam{
-				StreamID:      streamID,
-				BlockFragment: chunk,
-				EndStream:     endStream,
-				EndHeaders:    endHeaders,
-			})
-			first = false
-		} else {
-			cc.fr.WriteContinuation(streamID, endHeaders, chunk)
-		}
-	}
-	cc.bw.Flush()
-	return cc.werr
-}
-
-// internal error values; they don't escape to callers
-var (
-	// abort request body write; don't send cancel
-	http2errStopReqBodyWrite = errors.New("http2: aborting request body write")
-
-	// abort request body write, but send stream reset of cancel.
-	http2errStopReqBodyWriteAndCancel = errors.New("http2: canceling request")
-
-	http2errReqBodyTooLong = errors.New("http2: request body larger than specified content length")
-)
-
-// frameScratchBufferLen returns the length of a buffer to use for
-// outgoing request bodies to read/write to/from.
-//
-// It returns max(1, min(peer's advertised max frame size,
-// Request.ContentLength+1, 512KB)).
-func (cs *http2clientStream) frameScratchBufferLen(maxFrameSize int) int {
-	const max = 512 << 10
-	n := int64(maxFrameSize)
-	if n > max {
-		n = max
-	}
-	if cl := cs.reqBodyContentLength; cl != -1 && cl+1 < n {
-		// Add an extra byte past the declared content-length to
-		// give the caller's Request.Body io.Reader a chance to
-		// give us more bytes than they declared, so we can catch it
-		// early.
-		n = cl + 1
-	}
-	if n < 1 {
-		return 1
-	}
-	return int(n) // doesn't truncate; max is 512K
-}
-
-var http2bufPool sync.Pool // of *[]byte
-
-func (cs *http2clientStream) writeRequestBody(req *Request) (err error) {
-	cc := cs.cc
-	body := cs.reqBody
-	sentEnd := false // whether we sent the final DATA frame w/ END_STREAM
-
-	hasTrailers := req.Trailer != nil
-	remainLen := cs.reqBodyContentLength
-	hasContentLen := remainLen != -1
-
-	cc.mu.Lock()
-	maxFrameSize := int(cc.maxFrameSize)
-	cc.mu.Unlock()
-
-	// Scratch buffer for reading into & writing from.
-	scratchLen := cs.frameScratchBufferLen(maxFrameSize)
-	var buf []byte
-	if bp, ok := http2bufPool.Get().(*[]byte); ok && len(*bp) >= scratchLen {
-		defer http2bufPool.Put(bp)
-		buf = *bp
-	} else {
-		buf = make([]byte, scratchLen)
-		defer http2bufPool.Put(&buf)
-	}
-
-	var sawEOF bool
-	for !sawEOF {
-		n, err := body.Read(buf[:len(buf)])
-		if hasContentLen {
-			remainLen -= int64(n)
-			if remainLen == 0 && err == nil {
-				// The request body's Content-Length was predeclared and
-				// we just finished reading it all, but the underlying io.Reader
-				// returned the final chunk with a nil error (which is one of
-				// the two valid things a Reader can do at EOF). Because we'd prefer
-				// to send the END_STREAM bit early, double-check that we're actually
-				// at EOF. Subsequent reads should return (0, EOF) at this point.
-				// If either value is different, we return an error in one of two ways below.
-				var scratch [1]byte
-				var n1 int
-				n1, err = body.Read(scratch[:])
-				remainLen -= int64(n1)
-			}
-			if remainLen < 0 {
-				err = http2errReqBodyTooLong
-				return err
-			}
-		}
-		if err != nil {
-			cc.mu.Lock()
-			bodyClosed := cs.reqBodyClosed
-			cc.mu.Unlock()
-			switch {
-			case bodyClosed:
-				return http2errStopReqBodyWrite
-			case err == io.EOF:
-				sawEOF = true
-				err = nil
-			default:
-				return err
-			}
-		}
-
-		remain := buf[:n]
-		for len(remain) > 0 && err == nil {
-			var allowed int32
-			allowed, err = cs.awaitFlowControl(len(remain))
-			if err != nil {
-				return err
-			}
-			cc.wmu.Lock()
-			data := remain[:allowed]
-			remain = remain[allowed:]
-			sentEnd = sawEOF && len(remain) == 0 && !hasTrailers
-			err = cc.fr.WriteData(cs.ID, sentEnd, data)
-			if err == nil {
-				// TODO(bradfitz): this flush is for latency, not bandwidth.
-				// Most requests won't need this. Make this opt-in or
-				// opt-out?  Use some heuristic on the body type? Nagel-like
-				// timers?  Based on 'n'? Only last chunk of this for loop,
-				// unless flow control tokens are low? For now, always.
-				// If we change this, see comment below.
-				err = cc.bw.Flush()
-			}
-			cc.wmu.Unlock()
-		}
-		if err != nil {
-			return err
-		}
-	}
-
-	if sentEnd {
-		// Already sent END_STREAM (which implies we have no
-		// trailers) and flushed, because currently all
-		// WriteData frames above get a flush. So we're done.
-		return nil
-	}
-
-	// Since the RoundTrip contract permits the caller to "mutate or reuse"
-	// a request after the Response's Body is closed, verify that this hasn't
-	// happened before accessing the trailers.
-	cc.mu.Lock()
-	trailer := req.Trailer
-	err = cs.abortErr
-	cc.mu.Unlock()
-	if err != nil {
-		return err
-	}
-
-	cc.wmu.Lock()
-	defer cc.wmu.Unlock()
-	var trls []byte
-	if len(trailer) > 0 {
-		trls, err = cc.encodeTrailers(trailer)
-		if err != nil {
-			return err
-		}
-	}
-
-	// Two ways to send END_STREAM: either with trailers, or
-	// with an empty DATA frame.
-	if len(trls) > 0 {
-		err = cc.writeHeaders(cs.ID, true, maxFrameSize, trls)
-	} else {
-		err = cc.fr.WriteData(cs.ID, true, nil)
-	}
-	if ferr := cc.bw.Flush(); ferr != nil && err == nil {
-		err = ferr
-	}
-	return err
-}
-
-// awaitFlowControl waits for [1, min(maxBytes, cc.cs.maxFrameSize)] flow
-// control tokens from the server.
-// It returns either the non-zero number of tokens taken or an error
-// if the stream is dead.
-func (cs *http2clientStream) awaitFlowControl(maxBytes int) (taken int32, err error) {
-	cc := cs.cc
-	ctx := cs.ctx
-	cc.mu.Lock()
-	defer cc.mu.Unlock()
-	for {
-		if cc.closed {
-			return 0, http2errClientConnClosed
-		}
-		if cs.reqBodyClosed {
-			return 0, http2errStopReqBodyWrite
-		}
-		select {
-		case <-cs.abort:
-			return 0, cs.abortErr
-		case <-ctx.Done():
-			return 0, ctx.Err()
-		case <-cs.reqCancel:
-			return 0, http2errRequestCanceled
-		default:
-		}
-		if a := cs.flow.available(); a > 0 {
-			take := a
-			if int(take) > maxBytes {
-
-				take = int32(maxBytes) // can't truncate int; take is int32
-			}
-			if take > int32(cc.maxFrameSize) {
-				take = int32(cc.maxFrameSize)
-			}
-			cs.flow.take(take)
-			return take, nil
-		}
-		cc.cond.Wait()
-	}
-}
-
-var http2errNilRequestURL = errors.New("http2: Request.URI is nil")
-
-// requires cc.wmu be held.
-func (cc *http2ClientConn) encodeHeaders(req *Request, addGzipHeader bool, trailers string, contentLength int64) ([]byte, error) {
-	cc.hbuf.Reset()
-	if req.URL == nil {
-		return nil, http2errNilRequestURL
-	}
-
-	host := req.Host
-	if host == "" {
-		host = req.URL.Host
-	}
-	host, err := httpguts.PunycodeHostPort(host)
-	if err != nil {
-		return nil, err
-	}
-
-	var path string
-	if req.Method != "CONNECT" {
-		path = req.URL.RequestURI()
-		if !http2validPseudoPath(path) {
-			orig := path
-			path = strings.TrimPrefix(path, req.URL.Scheme+"://"+host)
-			if !http2validPseudoPath(path) {
-				if req.URL.Opaque != "" {
-					return nil, fmt.Errorf("invalid request :path %q from URL.Opaque = %q", orig, req.URL.Opaque)
-				} else {
-					return nil, fmt.Errorf("invalid request :path %q", orig)
-				}
-			}
-		}
-	}
-
-	// Check for any invalid headers and return an error before we
-	// potentially pollute our hpack state. (We want to be able to
-	// continue to reuse the hpack encoder for future requests)
-	for k, vv := range req.Header {
-		if !httpguts.ValidHeaderFieldName(k) {
-			return nil, fmt.Errorf("invalid HTTP header name %q", k)
-		}
-		for _, v := range vv {
-			if !httpguts.ValidHeaderFieldValue(v) {
-				return nil, fmt.Errorf("invalid HTTP header value %q for header %q", v, k)
-			}
-		}
-	}
-
-	enumerateHeaders := func(f func(name, value string)) {
-		// 8.1.2.3 Request Pseudo-Header Fields
-		// The :path pseudo-header field includes the path and query parts of the
-		// target URI (the path-absolute production and optionally a '?' character
-		// followed by the query production (see Sections 3.3 and 3.4 of
-		// [RFC3986]).
-		f(":authority", host)
-		m := req.Method
-		if m == "" {
-			m = MethodGet
-		}
-		f(":method", m)
-		if req.Method != "CONNECT" {
-			f(":path", path)
-			f(":scheme", req.URL.Scheme)
-		}
-		if trailers != "" {
-			f("trailer", trailers)
-		}
-
-		var didUA bool
-		for k, vv := range req.Header {
-			if http2asciiEqualFold(k, "host") || http2asciiEqualFold(k, "content-length") {
-				// Host is :authority, already sent.
-				// Content-Length is automatic, set below.
-				continue
-			} else if http2asciiEqualFold(k, "connection") ||
-				http2asciiEqualFold(k, "proxy-connection") ||
-				http2asciiEqualFold(k, "transfer-encoding") ||
-				http2asciiEqualFold(k, "upgrade") ||
-				http2asciiEqualFold(k, "keep-alive") {
-				// Per 8.1.2.2 Connection-Specific Header
-				// Fields, don't send connection-specific
-				// fields. We have already checked if any
-				// are error-worthy so just ignore the rest.
-				continue
-			} else if http2asciiEqualFold(k, "user-agent") {
-				// Match Go's http1 behavior: at most one
-				// User-Agent. If set to nil or empty string,
-				// then omit it. Otherwise if not mentioned,
-				// include the default (below).
-				didUA = true
-				if len(vv) < 1 {
-					continue
-				}
-				vv = vv[:1]
-				if vv[0] == "" {
-					continue
-				}
-			} else if http2asciiEqualFold(k, "cookie") {
-				// Per 8.1.2.5 To allow for better compression efficiency, the
-				// Cookie header field MAY be split into separate header fields,
-				// each with one or more cookie-pairs.
-				for _, v := range vv {
-					for {
-						p := strings.IndexByte(v, ';')
-						if p < 0 {
-							break
-						}
-						f("cookie", v[:p])
-						p++
-						// strip space after semicolon if any.
-						for p+1 <= len(v) && v[p] == ' ' {
-							p++
-						}
-						v = v[p:]
-					}
-					if len(v) > 0 {
-						f("cookie", v)
-					}
-				}
-				continue
-			}
-
-			for _, v := range vv {
-				f(k, v)
-			}
-		}
-		if http2shouldSendReqContentLength(req.Method, contentLength) {
-			f("content-length", strconv.FormatInt(contentLength, 10))
-		}
-		if addGzipHeader {
-			f("accept-encoding", "gzip")
-		}
-		if !didUA {
-			f("user-agent", http2defaultUserAgent)
-		}
-	}
-
-	// Do a first pass over the headers counting bytes to ensure
-	// we don't exceed cc.peerMaxHeaderListSize. This is done as a
-	// separate pass before encoding the headers to prevent
-	// modifying the hpack state.
-	hlSize := uint64(0)
-	enumerateHeaders(func(name, value string) {
-		hf := hpack.HeaderField{Name: name, Value: value}
-		hlSize += uint64(hf.Size())
-	})
-
-	if hlSize > cc.peerMaxHeaderListSize {
-		return nil, http2errRequestHeaderListSize
-	}
-
-	trace := httptrace.ContextClientTrace(req.Context())
-	traceHeaders := http2traceHasWroteHeaderField(trace)
-
-	// Header list size is ok. Write the headers.
-	enumerateHeaders(func(name, value string) {
-		name, ascii := http2asciiToLower(name)
-		if !ascii {
-			// Skip writing invalid headers. Per RFC 7540, Section 8.1.2, header
-			// field names have to be ASCII characters (just as in HTTP/1.x).
-			return
-		}
-		cc.writeHeader(name, value)
-		if traceHeaders {
-			http2traceWroteHeaderField(trace, name, value)
-		}
-	})
-
-	return cc.hbuf.Bytes(), nil
-}
-
-// shouldSendReqContentLength reports whether the http2.Transport should send
-// a "content-length" request header. This logic is basically a copy of the net/http
-// transferWriter.shouldSendContentLength.
-// The contentLength is the corrected contentLength (so 0 means actually 0, not unknown).
-// -1 means unknown.
-func http2shouldSendReqContentLength(method string, contentLength int64) bool {
-	if contentLength > 0 {
-		return true
-	}
-	if contentLength < 0 {
-		return false
-	}
-	// For zero bodies, whether we send a content-length depends on the method.
-	// It also kinda doesn't matter for http2 either way, with END_STREAM.
-	switch method {
-	case "POST", "PUT", "PATCH":
-		return true
-	default:
-		return false
-	}
-}
-
-// requires cc.wmu be held.
-func (cc *http2ClientConn) encodeTrailers(trailer Header) ([]byte, error) {
-	cc.hbuf.Reset()
-
-	hlSize := uint64(0)
-	for k, vv := range trailer {
-		for _, v := range vv {
-			hf := hpack.HeaderField{Name: k, Value: v}
-			hlSize += uint64(hf.Size())
-		}
-	}
-	if hlSize > cc.peerMaxHeaderListSize {
-		return nil, http2errRequestHeaderListSize
-	}
-
-	for k, vv := range trailer {
-		lowKey, ascii := http2asciiToLower(k)
-		if !ascii {
-			// Skip writing invalid headers. Per RFC 7540, Section 8.1.2, header
-			// field names have to be ASCII characters (just as in HTTP/1.x).
-			continue
-		}
-		// Transfer-Encoding, etc.. have already been filtered at the
-		// start of RoundTrip
-		for _, v := range vv {
-			cc.writeHeader(lowKey, v)
-		}
-	}
-	return cc.hbuf.Bytes(), nil
-}
-
-func (cc *http2ClientConn) writeHeader(name, value string) {
-	if http2VerboseLogs {
-		log.Printf("http2: Transport encoding header %q = %q", name, value)
-	}
-	cc.henc.WriteField(hpack.HeaderField{Name: name, Value: value})
-}
-
-type http2resAndError struct {
-	_   http2incomparable
-	res *Response
-	err error
-}
-
-// requires cc.mu be held.
-func (cc *http2ClientConn) addStreamLocked(cs *http2clientStream) {
-	cs.flow.add(int32(cc.initialWindowSize))
-	cs.flow.setConnFlow(&cc.flow)
-	cs.inflow.add(http2transportDefaultStreamFlow)
-	cs.inflow.setConnFlow(&cc.inflow)
-	cs.ID = cc.nextStreamID
-	cc.nextStreamID += 2
-	cc.streams[cs.ID] = cs
-	if cs.ID == 0 {
-		panic("assigned stream ID 0")
-	}
-}
-
-func (cc *http2ClientConn) forgetStreamID(id uint32) {
-	cc.mu.Lock()
-	slen := len(cc.streams)
-	delete(cc.streams, id)
-	if len(cc.streams) != slen-1 {
-		panic("forgetting unknown stream id")
-	}
-	cc.lastActive = time.Now()
-	if len(cc.streams) == 0 && cc.idleTimer != nil {
-		cc.idleTimer.Reset(cc.idleTimeout)
-		cc.lastIdle = time.Now()
-	}
-	// Wake up writeRequestBody via clientStream.awaitFlowControl and
-	// wake up RoundTrip if there is a pending request.
-	cc.cond.Broadcast()
-
-	closeOnIdle := cc.singleUse || cc.doNotReuse || cc.t.disableKeepAlives()
-	if closeOnIdle && cc.streamsReserved == 0 && len(cc.streams) == 0 {
-		if http2VerboseLogs {
-			cc.vlogf("http2: Transport closing idle conn %p (forSingleUse=%v, maxStream=%v)", cc, cc.singleUse, cc.nextStreamID-2)
-		}
-		cc.closed = true
-		defer cc.tconn.Close()
-	}
-
-	cc.mu.Unlock()
-}
-
-// clientConnReadLoop is the state owned by the clientConn's frame-reading readLoop.
-type http2clientConnReadLoop struct {
-	_  http2incomparable
-	cc *http2ClientConn
-}
-
-// readLoop runs in its own goroutine and reads and dispatches frames.
-func (cc *http2ClientConn) readLoop() {
-	rl := &http2clientConnReadLoop{cc: cc}
-	defer rl.cleanup()
-	cc.readerErr = rl.run()
-	if ce, ok := cc.readerErr.(http2ConnectionError); ok {
-		cc.wmu.Lock()
-		cc.fr.WriteGoAway(0, http2ErrCode(ce), nil)
-		cc.wmu.Unlock()
-	}
-}
-
-// GoAwayError is returned by the Transport when the server closes the
-// TCP connection after sending a GOAWAY frame.
-type http2GoAwayError struct {
-	LastStreamID uint32
-	ErrCode      http2ErrCode
-	DebugData    string
-}
-
-func (e http2GoAwayError) Error() string {
-	return fmt.Sprintf("http2: server sent GOAWAY and closed the connection; LastStreamID=%v, ErrCode=%v, debug=%q",
-		e.LastStreamID, e.ErrCode, e.DebugData)
-}
-
-func http2isEOFOrNetReadError(err error) bool {
-	if err == io.EOF {
-		return true
-	}
-	ne, ok := err.(*net.OpError)
-	return ok && ne.Op == "read"
-}
-
-func (rl *http2clientConnReadLoop) cleanup() {
-	cc := rl.cc
-	defer cc.tconn.Close()
-	defer cc.t.connPool().MarkDead(cc)
-	defer close(cc.readerDone)
-
-	if cc.idleTimer != nil {
-		cc.idleTimer.Stop()
-	}
-
-	// Close any response bodies if the server closes prematurely.
-	// TODO: also do this if we've written the headers but not
-	// gotten a response yet.
-	err := cc.readerErr
-	cc.mu.Lock()
-	if cc.goAway != nil && http2isEOFOrNetReadError(err) {
-		err = http2GoAwayError{
-			LastStreamID: cc.goAway.LastStreamID,
-			ErrCode:      cc.goAway.ErrCode,
-			DebugData:    cc.goAwayDebug,
-		}
-	} else if err == io.EOF {
-		err = io.ErrUnexpectedEOF
-	}
-	cc.closed = true
-	for _, cs := range cc.streams {
-		select {
-		case <-cs.peerClosed:
-			// The server closed the stream before closing the conn,
-			// so no need to interrupt it.
-		default:
-			cs.abortStreamLocked(err)
-		}
-	}
-	cc.cond.Broadcast()
-	cc.mu.Unlock()
-}
-
-// countReadFrameError calls Transport.CountError with a string
-// representing err.
-func (cc *http2ClientConn) countReadFrameError(err error) {
-	f := cc.t.CountError
-	if f == nil || err == nil {
-		return
-	}
-	if ce, ok := err.(http2ConnectionError); ok {
-		errCode := http2ErrCode(ce)
-		f(fmt.Sprintf("read_frame_conn_error_%s", errCode.stringToken()))
-		return
-	}
-	if errors.Is(err, io.EOF) {
-		f("read_frame_eof")
-		return
-	}
-	if errors.Is(err, io.ErrUnexpectedEOF) {
-		f("read_frame_unexpected_eof")
-		return
-	}
-	if errors.Is(err, http2ErrFrameTooLarge) {
-		f("read_frame_too_large")
-		return
-	}
-	f("read_frame_other")
-}
-
-func (rl *http2clientConnReadLoop) run() error {
-	cc := rl.cc
-	gotSettings := false
-	readIdleTimeout := cc.t.ReadIdleTimeout
-	var t *time.Timer
-	if readIdleTimeout != 0 {
-		t = time.AfterFunc(readIdleTimeout, cc.healthCheck)
-		defer t.Stop()
-	}
-	for {
-		f, err := cc.fr.ReadFrame()
-		if t != nil {
-			t.Reset(readIdleTimeout)
-		}
-		if err != nil {
-			cc.vlogf("http2: Transport readFrame error on conn %p: (%T) %v", cc, err, err)
-		}
-		if se, ok := err.(http2StreamError); ok {
-			if cs := rl.streamByID(se.StreamID); cs != nil {
-				if se.Cause == nil {
-					se.Cause = cc.fr.errDetail
-				}
-				rl.endStreamError(cs, se)
-			}
-			continue
-		} else if err != nil {
-			cc.countReadFrameError(err)
-			return err
-		}
-		if http2VerboseLogs {
-			cc.vlogf("http2: Transport received %s", http2summarizeFrame(f))
-		}
-		if !gotSettings {
-			if _, ok := f.(*http2SettingsFrame); !ok {
-				cc.logf("protocol error: received %T before a SETTINGS frame", f)
-				return http2ConnectionError(http2ErrCodeProtocol)
-			}
-			gotSettings = true
-		}
-
-		switch f := f.(type) {
-		case *http2MetaHeadersFrame:
-			err = rl.processHeaders(f)
-		case *http2DataFrame:
-			err = rl.processData(f)
-		case *http2GoAwayFrame:
-			err = rl.processGoAway(f)
-		case *http2RSTStreamFrame:
-			err = rl.processResetStream(f)
-		case *http2SettingsFrame:
-			err = rl.processSettings(f)
-		case *http2PushPromiseFrame:
-			err = rl.processPushPromise(f)
-		case *http2WindowUpdateFrame:
-			err = rl.processWindowUpdate(f)
-		case *http2PingFrame:
-			err = rl.processPing(f)
-		default:
-			cc.logf("Transport: unhandled response frame type %T", f)
-		}
-		if err != nil {
-			if http2VerboseLogs {
-				cc.vlogf("http2: Transport conn %p received error from processing frame %v: %v", cc, http2summarizeFrame(f), err)
-			}
-			return err
-		}
-	}
-}
-
-func (rl *http2clientConnReadLoop) processHeaders(f *http2MetaHeadersFrame) error {
-	cs := rl.streamByID(f.StreamID)
-	if cs == nil {
-		// We'd get here if we canceled a request while the
-		// server had its response still in flight. So if this
-		// was just something we canceled, ignore it.
-		return nil
-	}
-	if cs.readClosed {
-		rl.endStreamError(cs, http2StreamError{
-			StreamID: f.StreamID,
-			Code:     http2ErrCodeProtocol,
-			Cause:    errors.New("protocol error: headers after END_STREAM"),
-		})
-		return nil
-	}
-	if !cs.firstByte {
-		if cs.trace != nil {
-			// TODO(bradfitz): move first response byte earlier,
-			// when we first read the 9 byte header, not waiting
-			// until all the HEADERS+CONTINUATION frames have been
-			// merged. This works for now.
-			http2traceFirstResponseByte(cs.trace)
-		}
-		cs.firstByte = true
-	}
-	if !cs.pastHeaders {
-		cs.pastHeaders = true
-	} else {
-		return rl.processTrailers(cs, f)
-	}
-
-	res, err := rl.handleResponse(cs, f)
-	if err != nil {
-		if _, ok := err.(http2ConnectionError); ok {
-			return err
-		}
-		// Any other error type is a stream error.
-		rl.endStreamError(cs, http2StreamError{
-			StreamID: f.StreamID,
-			Code:     http2ErrCodeProtocol,
-			Cause:    err,
-		})
-		return nil // return nil from process* funcs to keep conn alive
-	}
-	if res == nil {
-		// (nil, nil) special case. See handleResponse docs.
-		return nil
-	}
-	cs.resTrailer = &res.Trailer
-	cs.res = res
-	close(cs.respHeaderRecv)
-	if f.StreamEnded() {
-		rl.endStream(cs)
-	}
-	return nil
-}
-
-// may return error types nil, or ConnectionError. Any other error value
-// is a StreamError of type ErrCodeProtocol. The returned error in that case
-// is the detail.
-//
-// As a special case, handleResponse may return (nil, nil) to skip the
-// frame (currently only used for 1xx responses).
-func (rl *http2clientConnReadLoop) handleResponse(cs *http2clientStream, f *http2MetaHeadersFrame) (*Response, error) {
-	if f.Truncated {
-		return nil, http2errResponseHeaderListSize
-	}
-
-	status := f.PseudoValue("status")
-	if status == "" {
-		return nil, errors.New("malformed response from server: missing status pseudo header")
-	}
-	statusCode, err := strconv.Atoi(status)
-	if err != nil {
-		return nil, errors.New("malformed response from server: malformed non-numeric status pseudo header")
-	}
-
-	regularFields := f.RegularFields()
-	strs := make([]string, len(regularFields))
-	header := make(Header, len(regularFields))
-	res := &Response{
-		Proto:      "HTTP/2.0",
-		ProtoMajor: 2,
-		Header:     header,
-		StatusCode: statusCode,
-		Status:     status + " " + StatusText(statusCode),
-	}
-	for _, hf := range regularFields {
-		key := CanonicalHeaderKey(hf.Name)
-		if key == "Trailer" {
-			t := res.Trailer
-			if t == nil {
-				t = make(Header)
-				res.Trailer = t
-			}
-			http2foreachHeaderElement(hf.Value, func(v string) {
-				t[CanonicalHeaderKey(v)] = nil
-			})
-		} else {
-			vv := header[key]
-			if vv == nil && len(strs) > 0 {
-				// More than likely this will be a single-element key.
-				// Most headers aren't multi-valued.
-				// Set the capacity on strs[0] to 1, so any future append
-				// won't extend the slice into the other strings.
-				vv, strs = strs[:1:1], strs[1:]
-				vv[0] = hf.Value
-				header[key] = vv
-			} else {
-				header[key] = append(vv, hf.Value)
-			}
-		}
-	}
-
-	if statusCode >= 100 && statusCode <= 199 {
-		if f.StreamEnded() {
-			return nil, errors.New("1xx informational response with END_STREAM flag")
-		}
-		cs.num1xx++
-		const max1xxResponses = 5 // arbitrary bound on number of informational responses, same as net/http
-		if cs.num1xx > max1xxResponses {
-			return nil, errors.New("http2: too many 1xx informational responses")
-		}
-		if fn := cs.get1xxTraceFunc(); fn != nil {
-			if err := fn(statusCode, textproto.MIMEHeader(header)); err != nil {
-				return nil, err
-			}
-		}
-		if statusCode == 100 {
-			http2traceGot100Continue(cs.trace)
-			select {
-			case cs.on100 <- struct{}{}:
-			default:
-			}
-		}
-		cs.pastHeaders = false // do it all again
-		return nil, nil
-	}
-
-	res.ContentLength = -1
-	if clens := res.Header["Content-Length"]; len(clens) == 1 {
-		if cl, err := strconv.ParseUint(clens[0], 10, 63); err == nil {
-			res.ContentLength = int64(cl)
-		} else {
-			// TODO: care? unlike http/1, it won't mess up our framing, so it's
-			// more safe smuggling-wise to ignore.
-		}
-	} else if len(clens) > 1 {
-		// TODO: care? unlike http/1, it won't mess up our framing, so it's
-		// more safe smuggling-wise to ignore.
-	} else if f.StreamEnded() && !cs.isHead {
-		res.ContentLength = 0
-	}
-
-	if cs.isHead {
-		res.Body = http2noBody
-		return res, nil
-	}
-
-	if f.StreamEnded() {
-		if res.ContentLength > 0 {
-			res.Body = http2missingBody{}
-		} else {
-			res.Body = http2noBody
-		}
-		return res, nil
-	}
-
-	cs.bufPipe.setBuffer(&http2dataBuffer{expected: res.ContentLength})
-	cs.bytesRemain = res.ContentLength
-	res.Body = http2transportResponseBody{cs}
-
-	if cs.requestedGzip && http2asciiEqualFold(res.Header.Get("Content-Encoding"), "gzip") {
-		res.Header.Del("Content-Encoding")
-		res.Header.Del("Content-Length")
-		res.ContentLength = -1
-		res.Body = &http2gzipReader{body: res.Body}
-		res.Uncompressed = true
-	}
-	return res, nil
-}
-
-func (rl *http2clientConnReadLoop) processTrailers(cs *http2clientStream, f *http2MetaHeadersFrame) error {
-	if cs.pastTrailers {
-		// Too many HEADERS frames for this stream.
-		return http2ConnectionError(http2ErrCodeProtocol)
-	}
-	cs.pastTrailers = true
-	if !f.StreamEnded() {
-		// We expect that any headers for trailers also
-		// has END_STREAM.
-		return http2ConnectionError(http2ErrCodeProtocol)
-	}
-	if len(f.PseudoFields()) > 0 {
-		// No pseudo header fields are defined for trailers.
-		// TODO: ConnectionError might be overly harsh? Check.
-		return http2ConnectionError(http2ErrCodeProtocol)
-	}
-
-	trailer := make(Header)
-	for _, hf := range f.RegularFields() {
-		key := CanonicalHeaderKey(hf.Name)
-		trailer[key] = append(trailer[key], hf.Value)
-	}
-	cs.trailer = trailer
-
-	rl.endStream(cs)
-	return nil
-}
-
-// transportResponseBody is the concrete type of Transport.RoundTrip's
-// Response.Body. It is an io.ReadCloser.
-type http2transportResponseBody struct {
-	cs *http2clientStream
-}
-
-func (b http2transportResponseBody) Read(p []byte) (n int, err error) {
-	cs := b.cs
-	cc := cs.cc
-
-	if cs.readErr != nil {
-		return 0, cs.readErr
-	}
-	n, err = b.cs.bufPipe.Read(p)
-	if cs.bytesRemain != -1 {
-		if int64(n) > cs.bytesRemain {
-			n = int(cs.bytesRemain)
-			if err == nil {
-				err = errors.New("net/http: server replied with more than declared Content-Length; truncated")
-				cs.abortStream(err)
-			}
-			cs.readErr = err
-			return int(cs.bytesRemain), err
-		}
-		cs.bytesRemain -= int64(n)
-		if err == io.EOF && cs.bytesRemain > 0 {
-			err = io.ErrUnexpectedEOF
-			cs.readErr = err
-			return n, err
-		}
-	}
-	if n == 0 {
-		// No flow control tokens to send back.
-		return
-	}
-
-	cc.mu.Lock()
-	var connAdd, streamAdd int32
-	// Check the conn-level first, before the stream-level.
-	if v := cc.inflow.available(); v < http2transportDefaultConnFlow/2 {
-		connAdd = http2transportDefaultConnFlow - v
-		cc.inflow.add(connAdd)
-	}
-	if err == nil { // No need to refresh if the stream is over or failed.
-		// Consider any buffered body data (read from the conn but not
-		// consumed by the client) when computing flow control for this
-		// stream.
-		v := int(cs.inflow.available()) + cs.bufPipe.Len()
-		if v < http2transportDefaultStreamFlow-http2transportDefaultStreamMinRefresh {
-			streamAdd = int32(http2transportDefaultStreamFlow - v)
-			cs.inflow.add(streamAdd)
-		}
-	}
-	cc.mu.Unlock()
-
-	if connAdd != 0 || streamAdd != 0 {
-		cc.wmu.Lock()
-		defer cc.wmu.Unlock()
-		if connAdd != 0 {
-			cc.fr.WriteWindowUpdate(0, http2mustUint31(connAdd))
-		}
-		if streamAdd != 0 {
-			cc.fr.WriteWindowUpdate(cs.ID, http2mustUint31(streamAdd))
-		}
-		cc.bw.Flush()
-	}
-	return
-}
-
-var http2errClosedResponseBody = errors.New("http2: response body closed")
-
-func (b http2transportResponseBody) Close() error {
-	cs := b.cs
-	cc := cs.cc
-
-	unread := cs.bufPipe.Len()
-	if unread > 0 {
-		cc.mu.Lock()
-		// Return connection-level flow control.
-		if unread > 0 {
-			cc.inflow.add(int32(unread))
-		}
-		cc.mu.Unlock()
-
-		// TODO(dneil): Acquiring this mutex can block indefinitely.
-		// Move flow control return to a goroutine?
-		cc.wmu.Lock()
-		// Return connection-level flow control.
-		if unread > 0 {
-			cc.fr.WriteWindowUpdate(0, uint32(unread))
-		}
-		cc.bw.Flush()
-		cc.wmu.Unlock()
-	}
-
-	cs.bufPipe.BreakWithError(http2errClosedResponseBody)
-	cs.abortStream(http2errClosedResponseBody)
-
-	select {
-	case <-cs.donec:
-	case <-cs.ctx.Done():
-		// See golang/go#49366: The net/http package can cancel the
-		// request context after the response body is fully read.
-		// Don't treat this as an error.
-		return nil
-	case <-cs.reqCancel:
-		return http2errRequestCanceled
-	}
-	return nil
-}
-
-func (rl *http2clientConnReadLoop) processData(f *http2DataFrame) error {
-	cc := rl.cc
-	cs := rl.streamByID(f.StreamID)
-	data := f.Data()
-	if cs == nil {
-		cc.mu.Lock()
-		neverSent := cc.nextStreamID
-		cc.mu.Unlock()
-		if f.StreamID >= neverSent {
-			// We never asked for this.
-			cc.logf("http2: Transport received unsolicited DATA frame; closing connection")
-			return http2ConnectionError(http2ErrCodeProtocol)
-		}
-		// We probably did ask for this, but canceled. Just ignore it.
-		// TODO: be stricter here? only silently ignore things which
-		// we canceled, but not things which were closed normally
-		// by the peer? Tough without accumulating too much state.
-
-		// But at least return their flow control:
-		if f.Length > 0 {
-			cc.mu.Lock()
-			cc.inflow.add(int32(f.Length))
-			cc.mu.Unlock()
-
-			cc.wmu.Lock()
-			cc.fr.WriteWindowUpdate(0, uint32(f.Length))
-			cc.bw.Flush()
-			cc.wmu.Unlock()
-		}
-		return nil
-	}
-	if cs.readClosed {
-		cc.logf("protocol error: received DATA after END_STREAM")
-		rl.endStreamError(cs, http2StreamError{
-			StreamID: f.StreamID,
-			Code:     http2ErrCodeProtocol,
-		})
-		return nil
-	}
-	if !cs.firstByte {
-		cc.logf("protocol error: received DATA before a HEADERS frame")
-		rl.endStreamError(cs, http2StreamError{
-			StreamID: f.StreamID,
-			Code:     http2ErrCodeProtocol,
-		})
-		return nil
-	}
-	if f.Length > 0 {
-		if cs.isHead && len(data) > 0 {
-			cc.logf("protocol error: received DATA on a HEAD request")
-			rl.endStreamError(cs, http2StreamError{
-				StreamID: f.StreamID,
-				Code:     http2ErrCodeProtocol,
-			})
-			return nil
-		}
-		// Check connection-level flow control.
-		cc.mu.Lock()
-		if cs.inflow.available() >= int32(f.Length) {
-			cs.inflow.take(int32(f.Length))
-		} else {
-			cc.mu.Unlock()
-			return http2ConnectionError(http2ErrCodeFlowControl)
-		}
-		// Return any padded flow control now, since we won't
-		// refund it later on body reads.
-		var refund int
-		if pad := int(f.Length) - len(data); pad > 0 {
-			refund += pad
-		}
-
-		didReset := false
-		var err error
-		if len(data) > 0 {
-			if _, err = cs.bufPipe.Write(data); err != nil {
-				// Return len(data) now if the stream is already closed,
-				// since data will never be read.
-				didReset = true
-				refund += len(data)
-			}
-		}
-
-		if refund > 0 {
-			cc.inflow.add(int32(refund))
-			if !didReset {
-				cs.inflow.add(int32(refund))
-			}
-		}
-		cc.mu.Unlock()
-
-		if refund > 0 {
-			cc.wmu.Lock()
-			cc.fr.WriteWindowUpdate(0, uint32(refund))
-			if !didReset {
-				cc.fr.WriteWindowUpdate(cs.ID, uint32(refund))
-			}
-			cc.bw.Flush()
-			cc.wmu.Unlock()
-		}
-
-		if err != nil {
-			rl.endStreamError(cs, err)
-			return nil
-		}
-	}
-
-	if f.StreamEnded() {
-		rl.endStream(cs)
-	}
-	return nil
-}
-
-func (rl *http2clientConnReadLoop) endStream(cs *http2clientStream) {
-	// TODO: check that any declared content-length matches, like
-	// server.go's (*stream).endStream method.
-	if !cs.readClosed {
-		cs.readClosed = true
-		// Close cs.bufPipe and cs.peerClosed with cc.mu held to avoid a
-		// race condition: The caller can read io.EOF from Response.Body
-		// and close the body before we close cs.peerClosed, causing
-		// cleanupWriteRequest to send a RST_STREAM.
-		rl.cc.mu.Lock()
-		defer rl.cc.mu.Unlock()
-		cs.bufPipe.closeWithErrorAndCode(io.EOF, cs.copyTrailers)
-		close(cs.peerClosed)
-	}
-}
-
-func (rl *http2clientConnReadLoop) endStreamError(cs *http2clientStream, err error) {
-	cs.readAborted = true
-	cs.abortStream(err)
-}
-
-func (rl *http2clientConnReadLoop) streamByID(id uint32) *http2clientStream {
-	rl.cc.mu.Lock()
-	defer rl.cc.mu.Unlock()
-	cs := rl.cc.streams[id]
-	if cs != nil && !cs.readAborted {
-		return cs
-	}
-	return nil
-}
-
-func (cs *http2clientStream) copyTrailers() {
-	for k, vv := range cs.trailer {
-		t := cs.resTrailer
-		if *t == nil {
-			*t = make(Header)
-		}
-		(*t)[k] = vv
-	}
-}
-
-func (rl *http2clientConnReadLoop) processGoAway(f *http2GoAwayFrame) error {
-	cc := rl.cc
-	cc.t.connPool().MarkDead(cc)
-	if f.ErrCode != 0 {
-		// TODO: deal with GOAWAY more. particularly the error code
-		cc.vlogf("transport got GOAWAY with error code = %v", f.ErrCode)
-		if fn := cc.t.CountError; fn != nil {
-			fn("recv_goaway_" + f.ErrCode.stringToken())
-		}
-
-	}
-	cc.setGoAway(f)
-	return nil
-}
-
-func (rl *http2clientConnReadLoop) processSettings(f *http2SettingsFrame) error {
-	cc := rl.cc
-	// Locking both mu and wmu here allows frame encoding to read settings with only wmu held.
-	// Acquiring wmu when f.IsAck() is unnecessary, but convenient and mostly harmless.
-	cc.wmu.Lock()
-	defer cc.wmu.Unlock()
-
-	if err := rl.processSettingsNoWrite(f); err != nil {
-		return err
-	}
-	if !f.IsAck() {
-		cc.fr.WriteSettingsAck()
-		cc.bw.Flush()
-	}
-	return nil
-}
-
-func (rl *http2clientConnReadLoop) processSettingsNoWrite(f *http2SettingsFrame) error {
-	cc := rl.cc
-	cc.mu.Lock()
-	defer cc.mu.Unlock()
-
-	if f.IsAck() {
-		if cc.wantSettingsAck {
-			cc.wantSettingsAck = false
-			return nil
-		}
-		return http2ConnectionError(http2ErrCodeProtocol)
-	}
-
-	var seenMaxConcurrentStreams bool
-	err := f.ForeachSetting(func(s http2Setting) error {
-		switch s.ID {
-		case http2SettingMaxFrameSize:
-			cc.maxFrameSize = s.Val
-		case http2SettingMaxConcurrentStreams:
-			cc.maxConcurrentStreams = s.Val
-			seenMaxConcurrentStreams = true
-		case http2SettingMaxHeaderListSize:
-			cc.peerMaxHeaderListSize = uint64(s.Val)
-		case http2SettingInitialWindowSize:
-			// Values above the maximum flow-control
-			// window size of 2^31-1 MUST be treated as a
-			// connection error (Section 5.4.1) of type
-			// FLOW_CONTROL_ERROR.
-			if s.Val > math.MaxInt32 {
-				return http2ConnectionError(http2ErrCodeFlowControl)
-			}
-
-			// Adjust flow control of currently-open
-			// frames by the difference of the old initial
-			// window size and this one.
-			delta := int32(s.Val) - int32(cc.initialWindowSize)
-			for _, cs := range cc.streams {
-				cs.flow.add(delta)
-			}
-			cc.cond.Broadcast()
-
-			cc.initialWindowSize = s.Val
-		default:
-			// TODO(bradfitz): handle more settings? SETTINGS_HEADER_TABLE_SIZE probably.
-			cc.vlogf("Unhandled Setting: %v", s)
-		}
-		return nil
-	})
-	if err != nil {
-		return err
-	}
-
-	if !cc.seenSettings {
-		if !seenMaxConcurrentStreams {
-			// This was the servers initial SETTINGS frame and it
-			// didn't contain a MAX_CONCURRENT_STREAMS field so
-			// increase the number of concurrent streams this
-			// connection can establish to our default.
-			cc.maxConcurrentStreams = http2defaultMaxConcurrentStreams
-		}
-		cc.seenSettings = true
-	}
-
-	return nil
-}
-
-func (rl *http2clientConnReadLoop) processWindowUpdate(f *http2WindowUpdateFrame) error {
-	cc := rl.cc
-	cs := rl.streamByID(f.StreamID)
-	if f.StreamID != 0 && cs == nil {
-		return nil
-	}
-
-	cc.mu.Lock()
-	defer cc.mu.Unlock()
-
-	fl := &cc.flow
-	if cs != nil {
-		fl = &cs.flow
-	}
-	if !fl.add(int32(f.Increment)) {
-		return http2ConnectionError(http2ErrCodeFlowControl)
-	}
-	cc.cond.Broadcast()
-	return nil
-}
-
-func (rl *http2clientConnReadLoop) processResetStream(f *http2RSTStreamFrame) error {
-	cs := rl.streamByID(f.StreamID)
-	if cs == nil {
-		// TODO: return error if server tries to RST_STREAM an idle stream
-		return nil
-	}
-	serr := http2streamError(cs.ID, f.ErrCode)
-	serr.Cause = http2errFromPeer
-	if f.ErrCode == http2ErrCodeProtocol {
-		rl.cc.SetDoNotReuse()
-	}
-	if fn := cs.cc.t.CountError; fn != nil {
-		fn("recv_rststream_" + f.ErrCode.stringToken())
-	}
-	cs.abortStream(serr)
-
-	cs.bufPipe.CloseWithError(serr)
-	return nil
-}
-
-// Ping sends a PING frame to the server and waits for the ack.
-func (cc *http2ClientConn) Ping(ctx context.Context) error {
-	c := make(chan struct{})
-	// Generate a random payload
-	var p [8]byte
-	for {
-		if _, err := rand.Read(p[:]); err != nil {
-			return err
-		}
-		cc.mu.Lock()
-		// check for dup before insert
-		if _, found := cc.pings[p]; !found {
-			cc.pings[p] = c
-			cc.mu.Unlock()
-			break
-		}
-		cc.mu.Unlock()
-	}
-	errc := make(chan error, 1)
-	go func() {
-		cc.wmu.Lock()
-		defer cc.wmu.Unlock()
-		if err := cc.fr.WritePing(false, p); err != nil {
-			errc <- err
-			return
-		}
-		if err := cc.bw.Flush(); err != nil {
-			errc <- err
-			return
-		}
-	}()
-	select {
-	case <-c:
-		return nil
-	case err := <-errc:
-		return err
-	case <-ctx.Done():
-		return ctx.Err()
-	case <-cc.readerDone:
-		// connection closed
-		return cc.readerErr
-	}
-}
-
-func (rl *http2clientConnReadLoop) processPing(f *http2PingFrame) error {
-	if f.IsAck() {
-		cc := rl.cc
-		cc.mu.Lock()
-		defer cc.mu.Unlock()
-		// If ack, notify listener if any
-		if c, ok := cc.pings[f.Data]; ok {
-			close(c)
-			delete(cc.pings, f.Data)
-		}
-		return nil
-	}
-	cc := rl.cc
-	cc.wmu.Lock()
-	defer cc.wmu.Unlock()
-	if err := cc.fr.WritePing(true, f.Data); err != nil {
-		return err
-	}
-	return cc.bw.Flush()
-}
-
-func (rl *http2clientConnReadLoop) processPushPromise(f *http2PushPromiseFrame) error {
-	// We told the peer we don't want them.
-	// Spec says:
-	// "PUSH_PROMISE MUST NOT be sent if the SETTINGS_ENABLE_PUSH
-	// setting of the peer endpoint is set to 0. An endpoint that
-	// has set this setting and has received acknowledgement MUST
-	// treat the receipt of a PUSH_PROMISE frame as a connection
-	// error (Section 5.4.1) of type PROTOCOL_ERROR."
-	return http2ConnectionError(http2ErrCodeProtocol)
-}
-
-func (cc *http2ClientConn) writeStreamReset(streamID uint32, code http2ErrCode, err error) {
-	// TODO: map err to more interesting error codes, once the
-	// HTTP community comes up with some. But currently for
-	// RST_STREAM there's no equivalent to GOAWAY frame's debug
-	// data, and the error codes are all pretty vague ("cancel").
-	cc.wmu.Lock()
-	cc.fr.WriteRSTStream(streamID, code)
-	cc.bw.Flush()
-	cc.wmu.Unlock()
-}
-
-var (
-	http2errResponseHeaderListSize = errors.New("http2: response header list larger than advertised limit")
-	http2errRequestHeaderListSize  = errors.New("http2: request header list larger than peer's advertised limit")
-)
-
-func (cc *http2ClientConn) logf(format string, args ...interface{}) {
-	cc.t.logf(format, args...)
-}
-
-func (cc *http2ClientConn) vlogf(format string, args ...interface{}) {
-	cc.t.vlogf(format, args...)
-}
-
-func (t *http2Transport) vlogf(format string, args ...interface{}) {
-	if http2VerboseLogs {
-		t.logf(format, args...)
-	}
-}
-
-func (t *http2Transport) logf(format string, args ...interface{}) {
-	log.Printf(format, args...)
-}
-
-var http2noBody io.ReadCloser = ioutil.NopCloser(bytes.NewReader(nil))
-
-type http2missingBody struct{}
-
-func (http2missingBody) Close() error { return nil }
-
-func (http2missingBody) Read([]byte) (int, error) { return 0, io.ErrUnexpectedEOF }
-
-func http2strSliceContains(ss []string, s string) bool {
-	for _, v := range ss {
-		if v == s {
-			return true
-		}
-	}
-	return false
-}
-
-type http2erringRoundTripper struct{ err error }
-
-func (rt http2erringRoundTripper) RoundTripErr() error { return rt.err }
-
-func (rt http2erringRoundTripper) RoundTrip(*Request) (*Response, error) { return nil, rt.err }
-
-// gzipReader wraps a response body so it can lazily
-// call gzip.NewReader on the first call to Read
-type http2gzipReader struct {
-	_    http2incomparable
-	body io.ReadCloser // underlying Response.Body
-	zr   *gzip.Reader  // lazily-initialized gzip reader
-	zerr error         // sticky error
-}
-
-func (gz *http2gzipReader) Read(p []byte) (n int, err error) {
-	if gz.zerr != nil {
-		return 0, gz.zerr
-	}
-	if gz.zr == nil {
-		gz.zr, err = gzip.NewReader(gz.body)
-		if err != nil {
-			gz.zerr = err
-			return 0, err
-		}
-	}
-	return gz.zr.Read(p)
-}
-
-func (gz *http2gzipReader) Close() error {
-	return gz.body.Close()
-}
-
-type http2errorReader struct{ err error }
-
-func (r http2errorReader) Read(p []byte) (int, error) { return 0, r.err }
-
-// isConnectionCloseRequest reports whether req should use its own
-// connection for a single request and then close the connection.
-func http2isConnectionCloseRequest(req *Request) bool {
-	return req.Close || httpguts.HeaderValuesContainsToken(req.Header["Connection"], "close")
-}
-
-// registerHTTPSProtocol calls Transport.RegisterProtocol but
-// converting panics into errors.
-func http2registerHTTPSProtocol(t *Transport, rt http2noDialH2RoundTripper) (err error) {
-	defer func() {
-		if e := recover(); e != nil {
-			err = fmt.Errorf("%v", e)
-		}
-	}()
-	t.RegisterProtocol("https", rt)
-	return nil
-}
-
-// noDialH2RoundTripper is a RoundTripper which only tries to complete the request
-// if there's already has a cached connection to the host.
-// (The field is exported so it can be accessed via reflect from net/http; tested
-// by TestNoDialH2RoundTripperType)
-type http2noDialH2RoundTripper struct{ *http2Transport }
-
-func (rt http2noDialH2RoundTripper) RoundTrip(req *Request) (*Response, error) {
-	res, err := rt.http2Transport.RoundTrip(req)
-	if http2isNoCachedConnError(err) {
-		return nil, ErrSkipAltProtocol
-	}
-	return res, err
-}
-
-func (t *http2Transport) idleConnTimeout() time.Duration {
-	if t.t1 != nil {
-		return t.t1.IdleConnTimeout
-	}
-	return 0
-}
-
-func http2traceGetConn(req *Request, hostPort string) {
-	trace := httptrace.ContextClientTrace(req.Context())
-	if trace == nil || trace.GetConn == nil {
-		return
-	}
-	trace.GetConn(hostPort)
-}
-
-func http2traceGotConn(req *Request, cc *http2ClientConn, reused bool) {
-	trace := httptrace.ContextClientTrace(req.Context())
-	if trace == nil || trace.GotConn == nil {
-		return
-	}
-	ci := httptrace.GotConnInfo{Conn: cc.tconn}
-	ci.Reused = reused
-	cc.mu.Lock()
-	ci.WasIdle = len(cc.streams) == 0 && reused
-	if ci.WasIdle && !cc.lastActive.IsZero() {
-		ci.IdleTime = time.Now().Sub(cc.lastActive)
-	}
-	cc.mu.Unlock()
-
-	trace.GotConn(ci)
-}
-
-func http2traceWroteHeaders(trace *httptrace.ClientTrace) {
-	if trace != nil && trace.WroteHeaders != nil {
-		trace.WroteHeaders()
-	}
-}
-
-func http2traceGot100Continue(trace *httptrace.ClientTrace) {
-	if trace != nil && trace.Got100Continue != nil {
-		trace.Got100Continue()
-	}
-}
-
-func http2traceWait100Continue(trace *httptrace.ClientTrace) {
-	if trace != nil && trace.Wait100Continue != nil {
-		trace.Wait100Continue()
-	}
-}
-
-func http2traceWroteRequest(trace *httptrace.ClientTrace, err error) {
-	if trace != nil && trace.WroteRequest != nil {
-		trace.WroteRequest(httptrace.WroteRequestInfo{Err: err})
-	}
-}
-
-func http2traceFirstResponseByte(trace *httptrace.ClientTrace) {
-	if trace != nil && trace.GotFirstResponseByte != nil {
-		trace.GotFirstResponseByte()
-	}
-}
-
-// writeFramer is implemented by any type that is used to write frames.
-type http2writeFramer interface {
-	writeFrame(http2writeContext) error
-
-	// staysWithinBuffer reports whether this writer promises that
-	// it will only write less than or equal to size bytes, and it
-	// won't Flush the write context.
-	staysWithinBuffer(size int) bool
-}
-
-// writeContext is the interface needed by the various frame writer
-// types below. All the writeFrame methods below are scheduled via the
-// frame writing scheduler (see writeScheduler in writesched.go).
-//
-// This interface is implemented by *serverConn.
-//
-// TODO: decide whether to a) use this in the client code (which didn't
-// end up using this yet, because it has a simpler design, not
-// currently implementing priorities), or b) delete this and
-// make the server code a bit more concrete.
-type http2writeContext interface {
-	Framer() *http2Framer
-	Flush() error
-	CloseConn() error
-	// HeaderEncoder returns an HPACK encoder that writes to the
-	// returned buffer.
-	HeaderEncoder() (*hpack.Encoder, *bytes.Buffer)
-}
-
-// writeEndsStream reports whether w writes a frame that will transition
-// the stream to a half-closed local state. This returns false for RST_STREAM,
-// which closes the entire stream (not just the local half).
-func http2writeEndsStream(w http2writeFramer) bool {
-	switch v := w.(type) {
-	case *http2writeData:
-		return v.endStream
-	case *http2writeResHeaders:
-		return v.endStream
-	case nil:
-		// This can only happen if the caller reuses w after it's
-		// been intentionally nil'ed out to prevent use. Keep this
-		// here to catch future refactoring breaking it.
-		panic("writeEndsStream called on nil writeFramer")
-	}
-	return false
-}
-
-type http2flushFrameWriter struct{}
-
-func (http2flushFrameWriter) writeFrame(ctx http2writeContext) error {
-	return ctx.Flush()
-}
-
-func (http2flushFrameWriter) staysWithinBuffer(max int) bool { return false }
-
-type http2writeSettings []http2Setting
-
-func (s http2writeSettings) staysWithinBuffer(max int) bool {
-	const settingSize = 6 // uint16 + uint32
-	return http2frameHeaderLen+settingSize*len(s) <= max
-
-}
-
-func (s http2writeSettings) writeFrame(ctx http2writeContext) error {
-	return ctx.Framer().WriteSettings([]http2Setting(s)...)
-}
-
-type http2writeGoAway struct {
-	maxStreamID uint32
-	code        http2ErrCode
-}
-
-func (p *http2writeGoAway) writeFrame(ctx http2writeContext) error {
-	err := ctx.Framer().WriteGoAway(p.maxStreamID, p.code, nil)
-	ctx.Flush() // ignore error: we're hanging up on them anyway
-	return err
-}
-
-func (*http2writeGoAway) staysWithinBuffer(max int) bool { return false } // flushes
-
-type http2writeData struct {
-	streamID  uint32
-	p         []byte
-	endStream bool
-}
-
-func (w *http2writeData) String() string {
-	return fmt.Sprintf("writeData(stream=%d, p=%d, endStream=%v)", w.streamID, len(w.p), w.endStream)
-}
-
-func (w *http2writeData) writeFrame(ctx http2writeContext) error {
-	return ctx.Framer().WriteData(w.streamID, w.endStream, w.p)
-}
-
-func (w *http2writeData) staysWithinBuffer(max int) bool {
-	return http2frameHeaderLen+len(w.p) <= max
-}
-
-// handlerPanicRST is the message sent from handler goroutines when
-// the handler panics.
-type http2handlerPanicRST struct {
-	StreamID uint32
-}
-
-func (hp http2handlerPanicRST) writeFrame(ctx http2writeContext) error {
-	return ctx.Framer().WriteRSTStream(hp.StreamID, http2ErrCodeInternal)
-}
-
-func (hp http2handlerPanicRST) staysWithinBuffer(max int) bool { return http2frameHeaderLen+4 <= max }
-
-func (se http2StreamError) writeFrame(ctx http2writeContext) error {
-	return ctx.Framer().WriteRSTStream(se.StreamID, se.Code)
-}
-
-func (se http2StreamError) staysWithinBuffer(max int) bool { return http2frameHeaderLen+4 <= max }
-
-type http2writePingAck struct{ pf *http2PingFrame }
-
-func (w http2writePingAck) writeFrame(ctx http2writeContext) error {
-	return ctx.Framer().WritePing(true, w.pf.Data)
-}
-
-func (w http2writePingAck) staysWithinBuffer(max int) bool {
-	return http2frameHeaderLen+len(w.pf.Data) <= max
-}
-
-type http2writeSettingsAck struct{}
-
-func (http2writeSettingsAck) writeFrame(ctx http2writeContext) error {
-	return ctx.Framer().WriteSettingsAck()
-}
-
-func (http2writeSettingsAck) staysWithinBuffer(max int) bool { return http2frameHeaderLen <= max }
-
-// splitHeaderBlock splits headerBlock into fragments so that each fragment fits
-// in a single frame, then calls fn for each fragment. firstFrag/lastFrag are true
-// for the first/last fragment, respectively.
-func http2splitHeaderBlock(ctx http2writeContext, headerBlock []byte, fn func(ctx http2writeContext, frag []byte, firstFrag, lastFrag bool) error) error {
-	// For now we're lazy and just pick the minimum MAX_FRAME_SIZE
-	// that all peers must support (16KB). Later we could care
-	// more and send larger frames if the peer advertised it, but
-	// there's little point. Most headers are small anyway (so we
-	// generally won't have CONTINUATION frames), and extra frames
-	// only waste 9 bytes anyway.
-	const maxFrameSize = 16384
-
-	first := true
-	for len(headerBlock) > 0 {
-		frag := headerBlock
-		if len(frag) > maxFrameSize {
-			frag = frag[:maxFrameSize]
-		}
-		headerBlock = headerBlock[len(frag):]
-		if err := fn(ctx, frag, first, len(headerBlock) == 0); err != nil {
-			return err
-		}
-		first = false
-	}
-	return nil
-}
-
-// writeResHeaders is a request to write a HEADERS and 0+ CONTINUATION frames
-// for HTTP response headers or trailers from a server handler.
-type http2writeResHeaders struct {
-	streamID    uint32
-	httpResCode int      // 0 means no ":status" line
-	h           Header   // may be nil
-	trailers    []string // if non-nil, which keys of h to write. nil means all.
-	endStream   bool
-
-	date          string
-	contentType   string
-	contentLength string
-}
-
-func http2encKV(enc *hpack.Encoder, k, v string) {
-	if http2VerboseLogs {
-		log.Printf("http2: server encoding header %q = %q", k, v)
-	}
-	enc.WriteField(hpack.HeaderField{Name: k, Value: v})
-}
-
-func (w *http2writeResHeaders) staysWithinBuffer(max int) bool {
-	// TODO: this is a common one. It'd be nice to return true
-	// here and get into the fast path if we could be clever and
-	// calculate the size fast enough, or at least a conservative
-	// upper bound that usually fires. (Maybe if w.h and
-	// w.trailers are nil, so we don't need to enumerate it.)
-	// Otherwise I'm afraid that just calculating the length to
-	// answer this question would be slower than the ~2µs benefit.
-	return false
-}
-
-func (w *http2writeResHeaders) writeFrame(ctx http2writeContext) error {
-	enc, buf := ctx.HeaderEncoder()
-	buf.Reset()
-
-	if w.httpResCode != 0 {
-		http2encKV(enc, ":status", http2httpCodeString(w.httpResCode))
-	}
-
-	http2encodeHeaders(enc, w.h, w.trailers)
-
-	if w.contentType != "" {
-		http2encKV(enc, "content-type", w.contentType)
-	}
-	if w.contentLength != "" {
-		http2encKV(enc, "content-length", w.contentLength)
-	}
-	if w.date != "" {
-		http2encKV(enc, "date", w.date)
-	}
-
-	headerBlock := buf.Bytes()
-	if len(headerBlock) == 0 && w.trailers == nil {
-		panic("unexpected empty hpack")
-	}
-
-	return http2splitHeaderBlock(ctx, headerBlock, w.writeHeaderBlock)
-}
-
-func (w *http2writeResHeaders) writeHeaderBlock(ctx http2writeContext, frag []byte, firstFrag, lastFrag bool) error {
-	if firstFrag {
-		return ctx.Framer().WriteHeaders(http2HeadersFrameParam{
-			StreamID:      w.streamID,
-			BlockFragment: frag,
-			EndStream:     w.endStream,
-			EndHeaders:    lastFrag,
-		})
-	} else {
-		return ctx.Framer().WriteContinuation(w.streamID, lastFrag, frag)
-	}
-}
-
-// writePushPromise is a request to write a PUSH_PROMISE and 0+ CONTINUATION frames.
-type http2writePushPromise struct {
-	streamID uint32   // pusher stream
-	method   string   // for :method
-	url      *url.URL // for :scheme, :authority, :path
-	h        Header
-
-	// Creates an ID for a pushed stream. This runs on serveG just before
-	// the frame is written. The returned ID is copied to promisedID.
-	allocatePromisedID func() (uint32, error)
-	promisedID         uint32
-}
-
-func (w *http2writePushPromise) staysWithinBuffer(max int) bool {
-	// TODO: see writeResHeaders.staysWithinBuffer
-	return false
-}
-
-func (w *http2writePushPromise) writeFrame(ctx http2writeContext) error {
-	enc, buf := ctx.HeaderEncoder()
-	buf.Reset()
-
-	http2encKV(enc, ":method", w.method)
-	http2encKV(enc, ":scheme", w.url.Scheme)
-	http2encKV(enc, ":authority", w.url.Host)
-	http2encKV(enc, ":path", w.url.RequestURI())
-	http2encodeHeaders(enc, w.h, nil)
-
-	headerBlock := buf.Bytes()
-	if len(headerBlock) == 0 {
-		panic("unexpected empty hpack")
-	}
-
-	return http2splitHeaderBlock(ctx, headerBlock, w.writeHeaderBlock)
-}
-
-func (w *http2writePushPromise) writeHeaderBlock(ctx http2writeContext, frag []byte, firstFrag, lastFrag bool) error {
-	if firstFrag {
-		return ctx.Framer().WritePushPromise(http2PushPromiseParam{
-			StreamID:      w.streamID,
-			PromiseID:     w.promisedID,
-			BlockFragment: frag,
-			EndHeaders:    lastFrag,
-		})
-	} else {
-		return ctx.Framer().WriteContinuation(w.streamID, lastFrag, frag)
-	}
-}
-
-type http2write100ContinueHeadersFrame struct {
-	streamID uint32
-}
-
-func (w http2write100ContinueHeadersFrame) writeFrame(ctx http2writeContext) error {
-	enc, buf := ctx.HeaderEncoder()
-	buf.Reset()
-	http2encKV(enc, ":status", "100")
-	return ctx.Framer().WriteHeaders(http2HeadersFrameParam{
-		StreamID:      w.streamID,
-		BlockFragment: buf.Bytes(),
-		EndStream:     false,
-		EndHeaders:    true,
-	})
-}
-
-func (w http2write100ContinueHeadersFrame) staysWithinBuffer(max int) bool {
-	// Sloppy but conservative:
-	return 9+2*(len(":status")+len("100")) <= max
-}
-
-type http2writeWindowUpdate struct {
-	streamID uint32 // or 0 for conn-level
-	n        uint32
-}
-
-func (wu http2writeWindowUpdate) staysWithinBuffer(max int) bool { return http2frameHeaderLen+4 <= max }
-
-func (wu http2writeWindowUpdate) writeFrame(ctx http2writeContext) error {
-	return ctx.Framer().WriteWindowUpdate(wu.streamID, wu.n)
-}
-
-// encodeHeaders encodes an http.Header. If keys is not nil, then (k, h[k])
-// is encoded only if k is in keys.
-func http2encodeHeaders(enc *hpack.Encoder, h Header, keys []string) {
-	if keys == nil {
-		sorter := http2sorterPool.Get().(*http2sorter)
-		// Using defer here, since the returned keys from the
-		// sorter.Keys method is only valid until the sorter
-		// is returned:
-		defer http2sorterPool.Put(sorter)
-		keys = sorter.Keys(h)
-	}
-	for _, k := range keys {
-		vv := h[k]
-		k, ascii := http2lowerHeader(k)
-		if !ascii {
-			// Skip writing invalid headers. Per RFC 7540, Section 8.1.2, header
-			// field names have to be ASCII characters (just as in HTTP/1.x).
-			continue
-		}
-		if !http2validWireHeaderFieldName(k) {
-			// Skip it as backup paranoia. Per
-			// golang.org/issue/14048, these should
-			// already be rejected at a higher level.
-			continue
-		}
-		isTE := k == "transfer-encoding"
-		for _, v := range vv {
-			if !httpguts.ValidHeaderFieldValue(v) {
-				// TODO: return an error? golang.org/issue/14048
-				// For now just omit it.
-				continue
-			}
-			// TODO: more of "8.1.2.2 Connection-Specific Header Fields"
-			if isTE && v != "trailers" {
-				continue
-			}
-			http2encKV(enc, k, v)
-		}
-	}
-}
-
-// WriteScheduler is the interface implemented by HTTP/2 write schedulers.
-// Methods are never called concurrently.
-type http2WriteScheduler interface {
-	// OpenStream opens a new stream in the write scheduler.
-	// It is illegal to call this with streamID=0 or with a streamID that is
-	// already open -- the call may panic.
-	OpenStream(streamID uint32, options http2OpenStreamOptions)
-
-	// CloseStream closes a stream in the write scheduler. Any frames queued on
-	// this stream should be discarded. It is illegal to call this on a stream
-	// that is not open -- the call may panic.
-	CloseStream(streamID uint32)
-
-	// AdjustStream adjusts the priority of the given stream. This may be called
-	// on a stream that has not yet been opened or has been closed. Note that
-	// RFC 7540 allows PRIORITY frames to be sent on streams in any state. See:
-	// https://tools.ietf.org/html/rfc7540#section-5.1
-	AdjustStream(streamID uint32, priority http2PriorityParam)
-
-	// Push queues a frame in the scheduler. In most cases, this will not be
-	// called with wr.StreamID()!=0 unless that stream is currently open. The one
-	// exception is RST_STREAM frames, which may be sent on idle or closed streams.
-	Push(wr http2FrameWriteRequest)
-
-	// Pop dequeues the next frame to write. Returns false if no frames can
-	// be written. Frames with a given wr.StreamID() are Pop'd in the same
-	// order they are Push'd, except RST_STREAM frames. No frames should be
-	// discarded except by CloseStream.
-	Pop() (wr http2FrameWriteRequest, ok bool)
-}
-
-// OpenStreamOptions specifies extra options for WriteScheduler.OpenStream.
-type http2OpenStreamOptions struct {
-	// PusherID is zero if the stream was initiated by the client. Otherwise,
-	// PusherID names the stream that pushed the newly opened stream.
-	PusherID uint32
-}
-
-// FrameWriteRequest is a request to write a frame.
-type http2FrameWriteRequest struct {
-	// write is the interface value that does the writing, once the
-	// WriteScheduler has selected this frame to write. The write
-	// functions are all defined in write.go.
-	write http2writeFramer
-
-	// stream is the stream on which this frame will be written.
-	// nil for non-stream frames like PING and SETTINGS.
-	// nil for RST_STREAM streams, which use the StreamError.StreamID field instead.
-	stream *http2stream
-
-	// done, if non-nil, must be a buffered channel with space for
-	// 1 message and is sent the return value from write (or an
-	// earlier error) when the frame has been written.
-	done chan error
-}
-
-// StreamID returns the id of the stream this frame will be written to.
-// 0 is used for non-stream frames such as PING and SETTINGS.
-func (wr http2FrameWriteRequest) StreamID() uint32 {
-	if wr.stream == nil {
-		if se, ok := wr.write.(http2StreamError); ok {
-			// (*serverConn).resetStream doesn't set
-			// stream because it doesn't necessarily have
-			// one. So special case this type of write
-			// message.
-			return se.StreamID
-		}
-		return 0
-	}
-	return wr.stream.id
-}
-
-// isControl reports whether wr is a control frame for MaxQueuedControlFrames
-// purposes. That includes non-stream frames and RST_STREAM frames.
-func (wr http2FrameWriteRequest) isControl() bool {
-	return wr.stream == nil
-}
-
-// DataSize returns the number of flow control bytes that must be consumed
-// to write this entire frame. This is 0 for non-DATA frames.
-func (wr http2FrameWriteRequest) DataSize() int {
-	if wd, ok := wr.write.(*http2writeData); ok {
-		return len(wd.p)
-	}
-	return 0
-}
-
-// Consume consumes min(n, available) bytes from this frame, where available
-// is the number of flow control bytes available on the stream. Consume returns
-// 0, 1, or 2 frames, where the integer return value gives the number of frames
-// returned.
-//
-// If flow control prevents consuming any bytes, this returns (_, _, 0). If
-// the entire frame was consumed, this returns (wr, _, 1). Otherwise, this
-// returns (consumed, rest, 2), where 'consumed' contains the consumed bytes and
-// 'rest' contains the remaining bytes. The consumed bytes are deducted from the
-// underlying stream's flow control budget.
-func (wr http2FrameWriteRequest) Consume(n int32) (http2FrameWriteRequest, http2FrameWriteRequest, int) {
-	var empty http2FrameWriteRequest
-
-	// Non-DATA frames are always consumed whole.
-	wd, ok := wr.write.(*http2writeData)
-	if !ok || len(wd.p) == 0 {
-		return wr, empty, 1
-	}
-
-	// Might need to split after applying limits.
-	allowed := wr.stream.flow.available()
-	if n < allowed {
-		allowed = n
-	}
-	if wr.stream.sc.maxFrameSize < allowed {
-		allowed = wr.stream.sc.maxFrameSize
-	}
-	if allowed <= 0 {
-		return empty, empty, 0
-	}
-	if len(wd.p) > int(allowed) {
-		wr.stream.flow.take(allowed)
-		consumed := http2FrameWriteRequest{
-			stream: wr.stream,
-			write: &http2writeData{
-				streamID: wd.streamID,
-				p:        wd.p[:allowed],
-				// Even if the original had endStream set, there
-				// are bytes remaining because len(wd.p) > allowed,
-				// so we know endStream is false.
-				endStream: false,
-			},
-			// Our caller is blocking on the final DATA frame, not
-			// this intermediate frame, so no need to wait.
-			done: nil,
-		}
-		rest := http2FrameWriteRequest{
-			stream: wr.stream,
-			write: &http2writeData{
-				streamID:  wd.streamID,
-				p:         wd.p[allowed:],
-				endStream: wd.endStream,
-			},
-			done: wr.done,
-		}
-		return consumed, rest, 2
-	}
-
-	// The frame is consumed whole.
-	// NB: This cast cannot overflow because allowed is <= math.MaxInt32.
-	wr.stream.flow.take(int32(len(wd.p)))
-	return wr, empty, 1
-}
-
-// String is for debugging only.
-func (wr http2FrameWriteRequest) String() string {
-	var des string
-	if s, ok := wr.write.(fmt.Stringer); ok {
-		des = s.String()
-	} else {
-		des = fmt.Sprintf("%T", wr.write)
-	}
-	return fmt.Sprintf("[FrameWriteRequest stream=%d, ch=%v, writer=%v]", wr.StreamID(), wr.done != nil, des)
-}
-
-// replyToWriter sends err to wr.done and panics if the send must block
-// This does nothing if wr.done is nil.
-func (wr *http2FrameWriteRequest) replyToWriter(err error) {
-	if wr.done == nil {
-		return
-	}
-	select {
-	case wr.done <- err:
-	default:
-		panic(fmt.Sprintf("unbuffered done channel passed in for type %T", wr.write))
-	}
-	wr.write = nil // prevent use (assume it's tainted after wr.done send)
-}
-
-// writeQueue is used by implementations of WriteScheduler.
-type http2writeQueue struct {
-	s []http2FrameWriteRequest
-}
-
-func (q *http2writeQueue) empty() bool { return len(q.s) == 0 }
-
-func (q *http2writeQueue) push(wr http2FrameWriteRequest) {
-	q.s = append(q.s, wr)
-}
-
-func (q *http2writeQueue) shift() http2FrameWriteRequest {
-	if len(q.s) == 0 {
-		panic("invalid use of queue")
-	}
-	wr := q.s[0]
-	// TODO: less copy-happy queue.
-	copy(q.s, q.s[1:])
-	q.s[len(q.s)-1] = http2FrameWriteRequest{}
-	q.s = q.s[:len(q.s)-1]
-	return wr
-}
-
-// consume consumes up to n bytes from q.s[0]. If the frame is
-// entirely consumed, it is removed from the queue. If the frame
-// is partially consumed, the frame is kept with the consumed
-// bytes removed. Returns true iff any bytes were consumed.
-func (q *http2writeQueue) consume(n int32) (http2FrameWriteRequest, bool) {
-	if len(q.s) == 0 {
-		return http2FrameWriteRequest{}, false
-	}
-	consumed, rest, numresult := q.s[0].Consume(n)
-	switch numresult {
-	case 0:
-		return http2FrameWriteRequest{}, false
-	case 1:
-		q.shift()
-	case 2:
-		q.s[0] = rest
-	}
-	return consumed, true
-}
-
-type http2writeQueuePool []*http2writeQueue
-
-// put inserts an unused writeQueue into the pool.
-
-// put inserts an unused writeQueue into the pool.
-func (p *http2writeQueuePool) put(q *http2writeQueue) {
-	for i := range q.s {
-		q.s[i] = http2FrameWriteRequest{}
-	}
-	q.s = q.s[:0]
-	*p = append(*p, q)
-}
-
-// get returns an empty writeQueue.
-func (p *http2writeQueuePool) get() *http2writeQueue {
-	ln := len(*p)
-	if ln == 0 {
-		return new(http2writeQueue)
-	}
-	x := ln - 1
-	q := (*p)[x]
-	(*p)[x] = nil
-	*p = (*p)[:x]
-	return q
-}
-
-// RFC 7540, Section 5.3.5: the default weight is 16.
-const http2priorityDefaultWeight = 15 // 16 = 15 + 1
-
-// PriorityWriteSchedulerConfig configures a priorityWriteScheduler.
-type http2PriorityWriteSchedulerConfig struct {
-	// MaxClosedNodesInTree controls the maximum number of closed streams to
-	// retain in the priority tree. Setting this to zero saves a small amount
-	// of memory at the cost of performance.
-	//
-	// See RFC 7540, Section 5.3.4:
-	//   "It is possible for a stream to become closed while prioritization
-	//   information ... is in transit. ... This potentially creates suboptimal
-	//   prioritization, since the stream could be given a priority that is
-	//   different from what is intended. To avoid these problems, an endpoint
-	//   SHOULD retain stream prioritization state for a period after streams
-	//   become closed. The longer state is retained, the lower the chance that
-	//   streams are assigned incorrect or default priority values."
-	MaxClosedNodesInTree int
-
-	// MaxIdleNodesInTree controls the maximum number of idle streams to
-	// retain in the priority tree. Setting this to zero saves a small amount
-	// of memory at the cost of performance.
-	//
-	// See RFC 7540, Section 5.3.4:
-	//   Similarly, streams that are in the "idle" state can be assigned
-	//   priority or become a parent of other streams. This allows for the
-	//   creation of a grouping node in the dependency tree, which enables
-	//   more flexible expressions of priority. Idle streams begin with a
-	//   default priority (Section 5.3.5).
-	MaxIdleNodesInTree int
-
-	// ThrottleOutOfOrderWrites enables write throttling to help ensure that
-	// data is delivered in priority order. This works around a race where
-	// stream B depends on stream A and both streams are about to call Write
-	// to queue DATA frames. If B wins the race, a naive scheduler would eagerly
-	// write as much data from B as possible, but this is suboptimal because A
-	// is a higher-priority stream. With throttling enabled, we write a small
-	// amount of data from B to minimize the amount of bandwidth that B can
-	// steal from A.
-	ThrottleOutOfOrderWrites bool
-}
-
-// NewPriorityWriteScheduler constructs a WriteScheduler that schedules
-// frames by following HTTP/2 priorities as described in RFC 7540 Section 5.3.
-// If cfg is nil, default options are used.
-func http2NewPriorityWriteScheduler(cfg *http2PriorityWriteSchedulerConfig) http2WriteScheduler {
-	if cfg == nil {
-		// For justification of these defaults, see:
-		// https://docs.google.com/document/d/1oLhNg1skaWD4_DtaoCxdSRN5erEXrH-KnLrMwEpOtFY
-		cfg = &http2PriorityWriteSchedulerConfig{
-			MaxClosedNodesInTree:     10,
-			MaxIdleNodesInTree:       10,
-			ThrottleOutOfOrderWrites: false,
-		}
-	}
-
-	ws := &http2priorityWriteScheduler{
-		nodes:                make(map[uint32]*http2priorityNode),
-		maxClosedNodesInTree: cfg.MaxClosedNodesInTree,
-		maxIdleNodesInTree:   cfg.MaxIdleNodesInTree,
-		enableWriteThrottle:  cfg.ThrottleOutOfOrderWrites,
-	}
-	ws.nodes[0] = &ws.root
-	if cfg.ThrottleOutOfOrderWrites {
-		ws.writeThrottleLimit = 1024
-	} else {
-		ws.writeThrottleLimit = math.MaxInt32
-	}
-	return ws
-}
-
-type http2priorityNodeState int
-
-const (
-	http2priorityNodeOpen http2priorityNodeState = iota
-	http2priorityNodeClosed
-	http2priorityNodeIdle
-)
-
-// priorityNode is a node in an HTTP/2 priority tree.
-// Each node is associated with a single stream ID.
-// See RFC 7540, Section 5.3.
-type http2priorityNode struct {
-	q            http2writeQueue        // queue of pending frames to write
-	id           uint32                 // id of the stream, or 0 for the root of the tree
-	weight       uint8                  // the actual weight is weight+1, so the value is in [1,256]
-	state        http2priorityNodeState // open | closed | idle
-	bytes        int64                  // number of bytes written by this node, or 0 if closed
-	subtreeBytes int64                  // sum(node.bytes) of all nodes in this subtree
-
-	// These links form the priority tree.
-	parent     *http2priorityNode
-	kids       *http2priorityNode // start of the kids list
-	prev, next *http2priorityNode // doubly-linked list of siblings
-}
-
-func (n *http2priorityNode) setParent(parent *http2priorityNode) {
-	if n == parent {
-		panic("setParent to self")
-	}
-	if n.parent == parent {
-		return
-	}
-	// Unlink from current parent.
-	if parent := n.parent; parent != nil {
-		if n.prev == nil {
-			parent.kids = n.next
-		} else {
-			n.prev.next = n.next
-		}
-		if n.next != nil {
-			n.next.prev = n.prev
-		}
-	}
-	// Link to new parent.
-	// If parent=nil, remove n from the tree.
-	// Always insert at the head of parent.kids (this is assumed by walkReadyInOrder).
-	n.parent = parent
-	if parent == nil {
-		n.next = nil
-		n.prev = nil
-	} else {
-		n.next = parent.kids
-		n.prev = nil
-		if n.next != nil {
-			n.next.prev = n
-		}
-		parent.kids = n
-	}
-}
-
-func (n *http2priorityNode) addBytes(b int64) {
-	n.bytes += b
-	for ; n != nil; n = n.parent {
-		n.subtreeBytes += b
-	}
-}
-
-// walkReadyInOrder iterates over the tree in priority order, calling f for each node
-// with a non-empty write queue. When f returns true, this function returns true and the
-// walk halts. tmp is used as scratch space for sorting.
-//
-// f(n, openParent) takes two arguments: the node to visit, n, and a bool that is true
-// if any ancestor p of n is still open (ignoring the root node).
-func (n *http2priorityNode) walkReadyInOrder(openParent bool, tmp *[]*http2priorityNode, f func(*http2priorityNode, bool) bool) bool {
-	if !n.q.empty() && f(n, openParent) {
-		return true
-	}
-	if n.kids == nil {
-		return false
-	}
-
-	// Don't consider the root "open" when updating openParent since
-	// we can't send data frames on the root stream (only control frames).
-	if n.id != 0 {
-		openParent = openParent || (n.state == http2priorityNodeOpen)
-	}
-
-	// Common case: only one kid or all kids have the same weight.
-	// Some clients don't use weights; other clients (like web browsers)
-	// use mostly-linear priority trees.
-	w := n.kids.weight
-	needSort := false
-	for k := n.kids.next; k != nil; k = k.next {
-		if k.weight != w {
-			needSort = true
-			break
-		}
-	}
-	if !needSort {
-		for k := n.kids; k != nil; k = k.next {
-			if k.walkReadyInOrder(openParent, tmp, f) {
-				return true
-			}
-		}
-		return false
-	}
-
-	// Uncommon case: sort the child nodes. We remove the kids from the parent,
-	// then re-insert after sorting so we can reuse tmp for future sort calls.
-	*tmp = (*tmp)[:0]
-	for n.kids != nil {
-		*tmp = append(*tmp, n.kids)
-		n.kids.setParent(nil)
-	}
-	sort.Sort(http2sortPriorityNodeSiblings(*tmp))
-	for i := len(*tmp) - 1; i >= 0; i-- {
-		(*tmp)[i].setParent(n) // setParent inserts at the head of n.kids
-	}
-	for k := n.kids; k != nil; k = k.next {
-		if k.walkReadyInOrder(openParent, tmp, f) {
-			return true
-		}
-	}
-	return false
-}
-
-type http2sortPriorityNodeSiblings []*http2priorityNode
-
-func (z http2sortPriorityNodeSiblings) Len() int { return len(z) }
-
-func (z http2sortPriorityNodeSiblings) Swap(i, k int) { z[i], z[k] = z[k], z[i] }
-
-func (z http2sortPriorityNodeSiblings) Less(i, k int) bool {
-	// Prefer the subtree that has sent fewer bytes relative to its weight.
-	// See sections 5.3.2 and 5.3.4.
-	wi, bi := float64(z[i].weight+1), float64(z[i].subtreeBytes)
-	wk, bk := float64(z[k].weight+1), float64(z[k].subtreeBytes)
-	if bi == 0 && bk == 0 {
-		return wi >= wk
-	}
-	if bk == 0 {
-		return false
-	}
-	return bi/bk <= wi/wk
-}
-
-type http2priorityWriteScheduler struct {
-	// root is the root of the priority tree, where root.id = 0.
-	// The root queues control frames that are not associated with any stream.
-	root http2priorityNode
-
-	// nodes maps stream ids to priority tree nodes.
-	nodes map[uint32]*http2priorityNode
-
-	// maxID is the maximum stream id in nodes.
-	maxID uint32
-
-	// lists of nodes that have been closed or are idle, but are kept in
-	// the tree for improved prioritization. When the lengths exceed either
-	// maxClosedNodesInTree or maxIdleNodesInTree, old nodes are discarded.
-	closedNodes, idleNodes []*http2priorityNode
-
-	// From the config.
-	maxClosedNodesInTree int
-	maxIdleNodesInTree   int
-	writeThrottleLimit   int32
-	enableWriteThrottle  bool
-
-	// tmp is scratch space for priorityNode.walkReadyInOrder to reduce allocations.
-	tmp []*http2priorityNode
-
-	// pool of empty queues for reuse.
-	queuePool http2writeQueuePool
-}
-
-func (ws *http2priorityWriteScheduler) OpenStream(streamID uint32, options http2OpenStreamOptions) {
-	// The stream may be currently idle but cannot be opened or closed.
-	if curr := ws.nodes[streamID]; curr != nil {
-		if curr.state != http2priorityNodeIdle {
-			panic(fmt.Sprintf("stream %d already opened", streamID))
-		}
-		curr.state = http2priorityNodeOpen
-		return
-	}
-
-	// RFC 7540, Section 5.3.5:
-	//  "All streams are initially assigned a non-exclusive dependency on stream 0x0.
-	//  Pushed streams initially depend on their associated stream. In both cases,
-	//  streams are assigned a default weight of 16."
-	parent := ws.nodes[options.PusherID]
-	if parent == nil {
-		parent = &ws.root
-	}
-	n := &http2priorityNode{
-		q:      *ws.queuePool.get(),
-		id:     streamID,
-		weight: http2priorityDefaultWeight,
-		state:  http2priorityNodeOpen,
-	}
-	n.setParent(parent)
-	ws.nodes[streamID] = n
-	if streamID > ws.maxID {
-		ws.maxID = streamID
-	}
-}
-
-func (ws *http2priorityWriteScheduler) CloseStream(streamID uint32) {
-	if streamID == 0 {
-		panic("violation of WriteScheduler interface: cannot close stream 0")
-	}
-	if ws.nodes[streamID] == nil {
-		panic(fmt.Sprintf("violation of WriteScheduler interface: unknown stream %d", streamID))
-	}
-	if ws.nodes[streamID].state != http2priorityNodeOpen {
-		panic(fmt.Sprintf("violation of WriteScheduler interface: stream %d already closed", streamID))
-	}
-
-	n := ws.nodes[streamID]
-	n.state = http2priorityNodeClosed
-	n.addBytes(-n.bytes)
-
-	q := n.q
-	ws.queuePool.put(&q)
-	n.q.s = nil
-	if ws.maxClosedNodesInTree > 0 {
-		ws.addClosedOrIdleNode(&ws.closedNodes, ws.maxClosedNodesInTree, n)
-	} else {
-		ws.removeNode(n)
-	}
-}
-
-func (ws *http2priorityWriteScheduler) AdjustStream(streamID uint32, priority http2PriorityParam) {
-	if streamID == 0 {
-		panic("adjustPriority on root")
-	}
-
-	// If streamID does not exist, there are two cases:
-	// - A closed stream that has been removed (this will have ID <= maxID)
-	// - An idle stream that is being used for "grouping" (this will have ID > maxID)
-	n := ws.nodes[streamID]
-	if n == nil {
-		if streamID <= ws.maxID || ws.maxIdleNodesInTree == 0 {
-			return
-		}
-		ws.maxID = streamID
-		n = &http2priorityNode{
-			q:      *ws.queuePool.get(),
-			id:     streamID,
-			weight: http2priorityDefaultWeight,
-			state:  http2priorityNodeIdle,
-		}
-		n.setParent(&ws.root)
-		ws.nodes[streamID] = n
-		ws.addClosedOrIdleNode(&ws.idleNodes, ws.maxIdleNodesInTree, n)
-	}
-
-	// Section 5.3.1: A dependency on a stream that is not currently in the tree
-	// results in that stream being given a default priority (Section 5.3.5).
-	parent := ws.nodes[priority.StreamDep]
-	if parent == nil {
-		n.setParent(&ws.root)
-		n.weight = http2priorityDefaultWeight
-		return
-	}
-
-	// Ignore if the client tries to make a node its own parent.
-	if n == parent {
-		return
-	}
-
-	// Section 5.3.3:
-	//   "If a stream is made dependent on one of its own dependencies, the
-	//   formerly dependent stream is first moved to be dependent on the
-	//   reprioritized stream's previous parent. The moved dependency retains
-	//   its weight."
-	//
-	// That is: if parent depends on n, move parent to depend on n.parent.
-	for x := parent.parent; x != nil; x = x.parent {
-		if x == n {
-			parent.setParent(n.parent)
-			break
-		}
-	}
-
-	// Section 5.3.3: The exclusive flag causes the stream to become the sole
-	// dependency of its parent stream, causing other dependencies to become
-	// dependent on the exclusive stream.
-	if priority.Exclusive {
-		k := parent.kids
-		for k != nil {
-			next := k.next
-			if k != n {
-				k.setParent(n)
-			}
-			k = next
-		}
-	}
-
-	n.setParent(parent)
-	n.weight = priority.Weight
-}
-
-func (ws *http2priorityWriteScheduler) Push(wr http2FrameWriteRequest) {
-	var n *http2priorityNode
-	if id := wr.StreamID(); id == 0 {
-		n = &ws.root
-	} else {
-		n = ws.nodes[id]
-		if n == nil {
-			// id is an idle or closed stream. wr should not be a HEADERS or
-			// DATA frame. However, wr can be a RST_STREAM. In this case, we
-			// push wr onto the root, rather than creating a new priorityNode,
-			// since RST_STREAM is tiny and the stream's priority is unknown
-			// anyway. See issue #17919.
-			if wr.DataSize() > 0 {
-				panic("add DATA on non-open stream")
-			}
-			n = &ws.root
-		}
-	}
-	n.q.push(wr)
-}
-
-func (ws *http2priorityWriteScheduler) Pop() (wr http2FrameWriteRequest, ok bool) {
-	ws.root.walkReadyInOrder(false, &ws.tmp, func(n *http2priorityNode, openParent bool) bool {
-		limit := int32(math.MaxInt32)
-		if openParent {
-			limit = ws.writeThrottleLimit
-		}
-		wr, ok = n.q.consume(limit)
-		if !ok {
-			return false
-		}
-		n.addBytes(int64(wr.DataSize()))
-		// If B depends on A and B continuously has data available but A
-		// does not, gradually increase the throttling limit to allow B to
-		// steal more and more bandwidth from A.
-		if openParent {
-			ws.writeThrottleLimit += 1024
-			if ws.writeThrottleLimit < 0 {
-				ws.writeThrottleLimit = math.MaxInt32
-			}
-		} else if ws.enableWriteThrottle {
-			ws.writeThrottleLimit = 1024
-		}
-		return true
-	})
-	return wr, ok
-}
-
-func (ws *http2priorityWriteScheduler) addClosedOrIdleNode(list *[]*http2priorityNode, maxSize int, n *http2priorityNode) {
-	if maxSize == 0 {
-		return
-	}
-	if len(*list) == maxSize {
-		// Remove the oldest node, then shift left.
-		ws.removeNode((*list)[0])
-		x := (*list)[1:]
-		copy(*list, x)
-		*list = (*list)[:len(x)]
-	}
-	*list = append(*list, n)
-}
-
-func (ws *http2priorityWriteScheduler) removeNode(n *http2priorityNode) {
-	for k := n.kids; k != nil; k = k.next {
-		k.setParent(n.parent)
-	}
-	n.setParent(nil)
-	delete(ws.nodes, n.id)
-}
-
-// NewRandomWriteScheduler constructs a WriteScheduler that ignores HTTP/2
-// priorities. Control frames like SETTINGS and PING are written before DATA
-// frames, but if no control frames are queued and multiple streams have queued
-// HEADERS or DATA frames, Pop selects a ready stream arbitrarily.
-func http2NewRandomWriteScheduler() http2WriteScheduler {
-	return &http2randomWriteScheduler{sq: make(map[uint32]*http2writeQueue)}
-}
-
-type http2randomWriteScheduler struct {
-	// zero are frames not associated with a specific stream.
-	zero http2writeQueue
-
-	// sq contains the stream-specific queues, keyed by stream ID.
-	// When a stream is idle, closed, or emptied, it's deleted
-	// from the map.
-	sq map[uint32]*http2writeQueue
-
-	// pool of empty queues for reuse.
-	queuePool http2writeQueuePool
-}
-
-func (ws *http2randomWriteScheduler) OpenStream(streamID uint32, options http2OpenStreamOptions) {
-	// no-op: idle streams are not tracked
-}
-
-func (ws *http2randomWriteScheduler) CloseStream(streamID uint32) {
-	q, ok := ws.sq[streamID]
-	if !ok {
-		return
-	}
-	delete(ws.sq, streamID)
-	ws.queuePool.put(q)
-}
-
-func (ws *http2randomWriteScheduler) AdjustStream(streamID uint32, priority http2PriorityParam) {
-	// no-op: priorities are ignored
-}
-
-func (ws *http2randomWriteScheduler) Push(wr http2FrameWriteRequest) {
-	if wr.isControl() {
-		ws.zero.push(wr)
-		return
-	}
-	id := wr.StreamID()
-	q, ok := ws.sq[id]
-	if !ok {
-		q = ws.queuePool.get()
-		ws.sq[id] = q
-	}
-	q.push(wr)
-}
-
-func (ws *http2randomWriteScheduler) Pop() (http2FrameWriteRequest, bool) {
-	// Control and RST_STREAM frames first.
-	if !ws.zero.empty() {
-		return ws.zero.shift(), true
-	}
-	// Iterate over all non-idle streams until finding one that can be consumed.
-	for streamID, q := range ws.sq {
-		if wr, ok := q.consume(math.MaxInt32); ok {
-			if q.empty() {
-				delete(ws.sq, streamID)
-				ws.queuePool.put(q)
-			}
-			return wr, true
-		}
-	}
-	return http2FrameWriteRequest{}, false
-}
diff --git a/contrib/go/_std_1.18/src/net/http/header.go b/contrib/go/_std_1.18/src/net/http/header.go
deleted file mode 100644
index 6437f2d2c0..0000000000
--- a/contrib/go/_std_1.18/src/net/http/header.go
+++ /dev/null
@@ -1,279 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package http
-
-import (
-	"io"
-	"net/http/httptrace"
-	"net/http/internal/ascii"
-	"net/textproto"
-	"sort"
-	"strings"
-	"sync"
-	"time"
-
-	"golang.org/x/net/http/httpguts"
-)
-
-// A Header represents the key-value pairs in an HTTP header.
-//
-// The keys should be in canonical form, as returned by
-// CanonicalHeaderKey.
-type Header map[string][]string
-
-// Add adds the key, value pair to the header.
-// It appends to any existing values associated with key.
-// The key is case insensitive; it is canonicalized by
-// CanonicalHeaderKey.
-func (h Header) Add(key, value string) {
-	textproto.MIMEHeader(h).Add(key, value)
-}
-
-// Set sets the header entries associated with key to the
-// single element value. It replaces any existing values
-// associated with key. The key is case insensitive; it is
-// canonicalized by textproto.CanonicalMIMEHeaderKey.
-// To use non-canonical keys, assign to the map directly.
-func (h Header) Set(key, value string) {
-	textproto.MIMEHeader(h).Set(key, value)
-}
-
-// Get gets the first value associated with the given key. If
-// there are no values associated with the key, Get returns "".
-// It is case insensitive; textproto.CanonicalMIMEHeaderKey is
-// used to canonicalize the provided key. To use non-canonical keys,
-// access the map directly.
-func (h Header) Get(key string) string {
-	return textproto.MIMEHeader(h).Get(key)
-}
-
-// Values returns all values associated with the given key.
-// It is case insensitive; textproto.CanonicalMIMEHeaderKey is
-// used to canonicalize the provided key. To use non-canonical
-// keys, access the map directly.
-// The returned slice is not a copy.
-func (h Header) Values(key string) []string {
-	return textproto.MIMEHeader(h).Values(key)
-}
-
-// get is like Get, but key must already be in CanonicalHeaderKey form.
-func (h Header) get(key string) string {
-	if v := h[key]; len(v) > 0 {
-		return v[0]
-	}
-	return ""
-}
-
-// has reports whether h has the provided key defined, even if it's
-// set to 0-length slice.
-func (h Header) has(key string) bool {
-	_, ok := h[key]
-	return ok
-}
-
-// Del deletes the values associated with key.
-// The key is case insensitive; it is canonicalized by
-// CanonicalHeaderKey.
-func (h Header) Del(key string) {
-	textproto.MIMEHeader(h).Del(key)
-}
-
-// Write writes a header in wire format.
-func (h Header) Write(w io.Writer) error {
-	return h.write(w, nil)
-}
-
-func (h Header) write(w io.Writer, trace *httptrace.ClientTrace) error {
-	return h.writeSubset(w, nil, trace)
-}
-
-// Clone returns a copy of h or nil if h is nil.
-func (h Header) Clone() Header {
-	if h == nil {
-		return nil
-	}
-
-	// Find total number of values.
-	nv := 0
-	for _, vv := range h {
-		nv += len(vv)
-	}
-	sv := make([]string, nv) // shared backing array for headers' values
-	h2 := make(Header, len(h))
-	for k, vv := range h {
-		if vv == nil {
-			// Preserve nil values. ReverseProxy distinguishes
-			// between nil and zero-length header values.
-			h2[k] = nil
-			continue
-		}
-		n := copy(sv, vv)
-		h2[k] = sv[:n:n]
-		sv = sv[n:]
-	}
-	return h2
-}
-
-var timeFormats = []string{
-	TimeFormat,
-	time.RFC850,
-	time.ANSIC,
-}
-
-// ParseTime parses a time header (such as the Date: header),
-// trying each of the three formats allowed by HTTP/1.1:
-// TimeFormat, time.RFC850, and time.ANSIC.
-func ParseTime(text string) (t time.Time, err error) {
-	for _, layout := range timeFormats {
-		t, err = time.Parse(layout, text)
-		if err == nil {
-			return
-		}
-	}
-	return
-}
-
-var headerNewlineToSpace = strings.NewReplacer("\n", " ", "\r", " ")
-
-// stringWriter implements WriteString on a Writer.
-type stringWriter struct {
-	w io.Writer
-}
-
-func (w stringWriter) WriteString(s string) (n int, err error) {
-	return w.w.Write([]byte(s))
-}
-
-type keyValues struct {
-	key    string
-	values []string
-}
-
-// A headerSorter implements sort.Interface by sorting a []keyValues
-// by key. It's used as a pointer, so it can fit in a sort.Interface
-// interface value without allocation.
-type headerSorter struct {
-	kvs []keyValues
-}
-
-func (s *headerSorter) Len() int           { return len(s.kvs) }
-func (s *headerSorter) Swap(i, j int)      { s.kvs[i], s.kvs[j] = s.kvs[j], s.kvs[i] }
-func (s *headerSorter) Less(i, j int) bool { return s.kvs[i].key < s.kvs[j].key }
-
-var headerSorterPool = sync.Pool{
-	New: func() any { return new(headerSorter) },
-}
-
-// sortedKeyValues returns h's keys sorted in the returned kvs
-// slice. The headerSorter used to sort is also returned, for possible
-// return to headerSorterCache.
-func (h Header) sortedKeyValues(exclude map[string]bool) (kvs []keyValues, hs *headerSorter) {
-	hs = headerSorterPool.Get().(*headerSorter)
-	if cap(hs.kvs) < len(h) {
-		hs.kvs = make([]keyValues, 0, len(h))
-	}
-	kvs = hs.kvs[:0]
-	for k, vv := range h {
-		if !exclude[k] {
-			kvs = append(kvs, keyValues{k, vv})
-		}
-	}
-	hs.kvs = kvs
-	sort.Sort(hs)
-	return kvs, hs
-}
-
-// WriteSubset writes a header in wire format.
-// If exclude is not nil, keys where exclude[key] == true are not written.
-// Keys are not canonicalized before checking the exclude map.
-func (h Header) WriteSubset(w io.Writer, exclude map[string]bool) error {
-	return h.writeSubset(w, exclude, nil)
-}
-
-func (h Header) writeSubset(w io.Writer, exclude map[string]bool, trace *httptrace.ClientTrace) error {
-	ws, ok := w.(io.StringWriter)
-	if !ok {
-		ws = stringWriter{w}
-	}
-	kvs, sorter := h.sortedKeyValues(exclude)
-	var formattedVals []string
-	for _, kv := range kvs {
-		if !httpguts.ValidHeaderFieldName(kv.key) {
-			// This could be an error. In the common case of
-			// writing response headers, however, we have no good
-			// way to provide the error back to the server
-			// handler, so just drop invalid headers instead.
-			continue
-		}
-		for _, v := range kv.values {
-			v = headerNewlineToSpace.Replace(v)
-			v = textproto.TrimString(v)
-			for _, s := range []string{kv.key, ": ", v, "\r\n"} {
-				if _, err := ws.WriteString(s); err != nil {
-					headerSorterPool.Put(sorter)
-					return err
-				}
-			}
-			if trace != nil && trace.WroteHeaderField != nil {
-				formattedVals = append(formattedVals, v)
-			}
-		}
-		if trace != nil && trace.WroteHeaderField != nil {
-			trace.WroteHeaderField(kv.key, formattedVals)
-			formattedVals = nil
-		}
-	}
-	headerSorterPool.Put(sorter)
-	return nil
-}
-
-// CanonicalHeaderKey returns the canonical format of the
-// header key s. The canonicalization converts the first
-// letter and any letter following a hyphen to upper case;
-// the rest are converted to lowercase. For example, the
-// canonical key for "accept-encoding" is "Accept-Encoding".
-// If s contains a space or invalid header field bytes, it is
-// returned without modifications.
-func CanonicalHeaderKey(s string) string { return textproto.CanonicalMIMEHeaderKey(s) }
-
-// hasToken reports whether token appears with v, ASCII
-// case-insensitive, with space or comma boundaries.
-// token must be all lowercase.
-// v may contain mixed cased.
-func hasToken(v, token string) bool {
-	if len(token) > len(v) || token == "" {
-		return false
-	}
-	if v == token {
-		return true
-	}
-	for sp := 0; sp <= len(v)-len(token); sp++ {
-		// Check that first character is good.
-		// The token is ASCII, so checking only a single byte
-		// is sufficient. We skip this potential starting
-		// position if both the first byte and its potential
-		// ASCII uppercase equivalent (b|0x20) don't match.
-		// False positives ('^' => '~') are caught by EqualFold.
-		if b := v[sp]; b != token[0] && b|0x20 != token[0] {
-			continue
-		}
-		// Check that start pos is on a valid token boundary.
-		if sp > 0 && !isTokenBoundary(v[sp-1]) {
-			continue
-		}
-		// Check that end pos is on a valid token boundary.
-		if endPos := sp + len(token); endPos != len(v) && !isTokenBoundary(v[endPos]) {
-			continue
-		}
-		if ascii.EqualFold(v[sp:sp+len(token)], token) {
-			return true
-		}
-	}
-	return false
-}
-
-func isTokenBoundary(b byte) bool {
-	return b == ' ' || b == ',' || b == '\t'
-}
diff --git a/contrib/go/_std_1.18/src/net/http/internal/chunked.go b/contrib/go/_std_1.18/src/net/http/internal/chunked.go
deleted file mode 100644
index 37a72e9031..0000000000
--- a/contrib/go/_std_1.18/src/net/http/internal/chunked.go
+++ /dev/null
@@ -1,261 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// The wire protocol for HTTP's "chunked" Transfer-Encoding.
-
-// Package internal contains HTTP internals shared by net/http and
-// net/http/httputil.
-package internal
-
-import (
-	"bufio"
-	"bytes"
-	"errors"
-	"fmt"
-	"io"
-)
-
-const maxLineLength = 4096 // assumed <= bufio.defaultBufSize
-
-var ErrLineTooLong = errors.New("header line too long")
-
-// NewChunkedReader returns a new chunkedReader that translates the data read from r
-// out of HTTP "chunked" format before returning it.
-// The chunkedReader returns io.EOF when the final 0-length chunk is read.
-//
-// NewChunkedReader is not needed by normal applications. The http package
-// automatically decodes chunking when reading response bodies.
-func NewChunkedReader(r io.Reader) io.Reader {
-	br, ok := r.(*bufio.Reader)
-	if !ok {
-		br = bufio.NewReader(r)
-	}
-	return &chunkedReader{r: br}
-}
-
-type chunkedReader struct {
-	r        *bufio.Reader
-	n        uint64 // unread bytes in chunk
-	err      error
-	buf      [2]byte
-	checkEnd bool // whether need to check for \r\n chunk footer
-}
-
-func (cr *chunkedReader) beginChunk() {
-	// chunk-size CRLF
-	var line []byte
-	line, cr.err = readChunkLine(cr.r)
-	if cr.err != nil {
-		return
-	}
-	cr.n, cr.err = parseHexUint(line)
-	if cr.err != nil {
-		return
-	}
-	if cr.n == 0 {
-		cr.err = io.EOF
-	}
-}
-
-func (cr *chunkedReader) chunkHeaderAvailable() bool {
-	n := cr.r.Buffered()
-	if n > 0 {
-		peek, _ := cr.r.Peek(n)
-		return bytes.IndexByte(peek, '\n') >= 0
-	}
-	return false
-}
-
-func (cr *chunkedReader) Read(b []uint8) (n int, err error) {
-	for cr.err == nil {
-		if cr.checkEnd {
-			if n > 0 && cr.r.Buffered() < 2 {
-				// We have some data. Return early (per the io.Reader
-				// contract) instead of potentially blocking while
-				// reading more.
-				break
-			}
-			if _, cr.err = io.ReadFull(cr.r, cr.buf[:2]); cr.err == nil {
-				if string(cr.buf[:]) != "\r\n" {
-					cr.err = errors.New("malformed chunked encoding")
-					break
-				}
-			} else {
-				if cr.err == io.EOF {
-					cr.err = io.ErrUnexpectedEOF
-				}
-				break
-			}
-			cr.checkEnd = false
-		}
-		if cr.n == 0 {
-			if n > 0 && !cr.chunkHeaderAvailable() {
-				// We've read enough. Don't potentially block
-				// reading a new chunk header.
-				break
-			}
-			cr.beginChunk()
-			continue
-		}
-		if len(b) == 0 {
-			break
-		}
-		rbuf := b
-		if uint64(len(rbuf)) > cr.n {
-			rbuf = rbuf[:cr.n]
-		}
-		var n0 int
-		n0, cr.err = cr.r.Read(rbuf)
-		n += n0
-		b = b[n0:]
-		cr.n -= uint64(n0)
-		// If we're at the end of a chunk, read the next two
-		// bytes to verify they are "\r\n".
-		if cr.n == 0 && cr.err == nil {
-			cr.checkEnd = true
-		} else if cr.err == io.EOF {
-			cr.err = io.ErrUnexpectedEOF
-		}
-	}
-	return n, cr.err
-}
-
-// Read a line of bytes (up to \n) from b.
-// Give up if the line exceeds maxLineLength.
-// The returned bytes are owned by the bufio.Reader
-// so they are only valid until the next bufio read.
-func readChunkLine(b *bufio.Reader) ([]byte, error) {
-	p, err := b.ReadSlice('\n')
-	if err != nil {
-		// We always know when EOF is coming.
-		// If the caller asked for a line, there should be a line.
-		if err == io.EOF {
-			err = io.ErrUnexpectedEOF
-		} else if err == bufio.ErrBufferFull {
-			err = ErrLineTooLong
-		}
-		return nil, err
-	}
-	if len(p) >= maxLineLength {
-		return nil, ErrLineTooLong
-	}
-	p = trimTrailingWhitespace(p)
-	p, err = removeChunkExtension(p)
-	if err != nil {
-		return nil, err
-	}
-	return p, nil
-}
-
-func trimTrailingWhitespace(b []byte) []byte {
-	for len(b) > 0 && isASCIISpace(b[len(b)-1]) {
-		b = b[:len(b)-1]
-	}
-	return b
-}
-
-func isASCIISpace(b byte) bool {
-	return b == ' ' || b == '\t' || b == '\n' || b == '\r'
-}
-
-var semi = []byte(";")
-
-// removeChunkExtension removes any chunk-extension from p.
-// For example,
-//     "0" => "0"
-//     "0;token" => "0"
-//     "0;token=val" => "0"
-//     `0;token="quoted string"` => "0"
-func removeChunkExtension(p []byte) ([]byte, error) {
-	p, _, _ = bytes.Cut(p, semi)
-	// TODO: care about exact syntax of chunk extensions? We're
-	// ignoring and stripping them anyway. For now just never
-	// return an error.
-	return p, nil
-}
-
-// NewChunkedWriter returns a new chunkedWriter that translates writes into HTTP
-// "chunked" format before writing them to w. Closing the returned chunkedWriter
-// sends the final 0-length chunk that marks the end of the stream but does
-// not send the final CRLF that appears after trailers; trailers and the last
-// CRLF must be written separately.
-//
-// NewChunkedWriter is not needed by normal applications. The http
-// package adds chunking automatically if handlers don't set a
-// Content-Length header. Using newChunkedWriter inside a handler
-// would result in double chunking or chunking with a Content-Length
-// length, both of which are wrong.
-func NewChunkedWriter(w io.Writer) io.WriteCloser {
-	return &chunkedWriter{w}
-}
-
-// Writing to chunkedWriter translates to writing in HTTP chunked Transfer
-// Encoding wire format to the underlying Wire chunkedWriter.
-type chunkedWriter struct {
-	Wire io.Writer
-}
-
-// Write the contents of data as one chunk to Wire.
-// NOTE: Note that the corresponding chunk-writing procedure in Conn.Write has
-// a bug since it does not check for success of io.WriteString
-func (cw *chunkedWriter) Write(data []byte) (n int, err error) {
-
-	// Don't send 0-length data. It looks like EOF for chunked encoding.
-	if len(data) == 0 {
-		return 0, nil
-	}
-
-	if _, err = fmt.Fprintf(cw.Wire, "%x\r\n", len(data)); err != nil {
-		return 0, err
-	}
-	if n, err = cw.Wire.Write(data); err != nil {
-		return
-	}
-	if n != len(data) {
-		err = io.ErrShortWrite
-		return
-	}
-	if _, err = io.WriteString(cw.Wire, "\r\n"); err != nil {
-		return
-	}
-	if bw, ok := cw.Wire.(*FlushAfterChunkWriter); ok {
-		err = bw.Flush()
-	}
-	return
-}
-
-func (cw *chunkedWriter) Close() error {
-	_, err := io.WriteString(cw.Wire, "0\r\n")
-	return err
-}
-
-// FlushAfterChunkWriter signals from the caller of NewChunkedWriter
-// that each chunk should be followed by a flush. It is used by the
-// http.Transport code to keep the buffering behavior for headers and
-// trailers, but flush out chunks aggressively in the middle for
-// request bodies which may be generated slowly. See Issue 6574.
-type FlushAfterChunkWriter struct {
-	*bufio.Writer
-}
-
-func parseHexUint(v []byte) (n uint64, err error) {
-	for i, b := range v {
-		switch {
-		case '0' <= b && b <= '9':
-			b = b - '0'
-		case 'a' <= b && b <= 'f':
-			b = b - 'a' + 10
-		case 'A' <= b && b <= 'F':
-			b = b - 'A' + 10
-		default:
-			return 0, errors.New("invalid byte in chunk length")
-		}
-		if i == 16 {
-			return 0, errors.New("http chunk length too large")
-		}
-		n <<= 4
-		n |= uint64(b)
-	}
-	return
-}
diff --git a/contrib/go/_std_1.18/src/net/http/request.go b/contrib/go/_std_1.18/src/net/http/request.go
deleted file mode 100644
index 76c2317d28..0000000000
--- a/contrib/go/_std_1.18/src/net/http/request.go
+++ /dev/null
@@ -1,1463 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// HTTP Request reading and parsing.
-
-package http
-
-import (
-	"bufio"
-	"bytes"
-	"context"
-	"crypto/tls"
-	"encoding/base64"
-	"errors"
-	"fmt"
-	"io"
-	"mime"
-	"mime/multipart"
-	"net"
-	"net/http/httptrace"
-	"net/http/internal/ascii"
-	"net/textproto"
-	"net/url"
-	urlpkg "net/url"
-	"strconv"
-	"strings"
-	"sync"
-
-	"golang.org/x/net/idna"
-)
-
-const (
-	defaultMaxMemory = 32 << 20 // 32 MB
-)
-
-// ErrMissingFile is returned by FormFile when the provided file field name
-// is either not present in the request or not a file field.
-var ErrMissingFile = errors.New("http: no such file")
-
-// ProtocolError represents an HTTP protocol error.
-//
-// Deprecated: Not all errors in the http package related to protocol errors
-// are of type ProtocolError.
-type ProtocolError struct {
-	ErrorString string
-}
-
-func (pe *ProtocolError) Error() string { return pe.ErrorString }
-
-var (
-	// ErrNotSupported is returned by the Push method of Pusher
-	// implementations to indicate that HTTP/2 Push support is not
-	// available.
-	ErrNotSupported = &ProtocolError{"feature not supported"}
-
-	// Deprecated: ErrUnexpectedTrailer is no longer returned by
-	// anything in the net/http package. Callers should not
-	// compare errors against this variable.
-	ErrUnexpectedTrailer = &ProtocolError{"trailer header without chunked transfer encoding"}
-
-	// ErrMissingBoundary is returned by Request.MultipartReader when the
-	// request's Content-Type does not include a "boundary" parameter.
-	ErrMissingBoundary = &ProtocolError{"no multipart boundary param in Content-Type"}
-
-	// ErrNotMultipart is returned by Request.MultipartReader when the
-	// request's Content-Type is not multipart/form-data.
-	ErrNotMultipart = &ProtocolError{"request Content-Type isn't multipart/form-data"}
-
-	// Deprecated: ErrHeaderTooLong is no longer returned by
-	// anything in the net/http package. Callers should not
-	// compare errors against this variable.
-	ErrHeaderTooLong = &ProtocolError{"header too long"}
-
-	// Deprecated: ErrShortBody is no longer returned by
-	// anything in the net/http package. Callers should not
-	// compare errors against this variable.
-	ErrShortBody = &ProtocolError{"entity body too short"}
-
-	// Deprecated: ErrMissingContentLength is no longer returned by
-	// anything in the net/http package. Callers should not
-	// compare errors against this variable.
-	ErrMissingContentLength = &ProtocolError{"missing ContentLength in HEAD response"}
-)
-
-func badStringError(what, val string) error { return fmt.Errorf("%s %q", what, val) }
-
-// Headers that Request.Write handles itself and should be skipped.
-var reqWriteExcludeHeader = map[string]bool{
-	"Host":              true, // not in Header map anyway
-	"User-Agent":        true,
-	"Content-Length":    true,
-	"Transfer-Encoding": true,
-	"Trailer":           true,
-}
-
-// A Request represents an HTTP request received by a server
-// or to be sent by a client.
-//
-// The field semantics differ slightly between client and server
-// usage. In addition to the notes on the fields below, see the
-// documentation for Request.Write and RoundTripper.
-type Request struct {
-	// Method specifies the HTTP method (GET, POST, PUT, etc.).
-	// For client requests, an empty string means GET.
-	//
-	// Go's HTTP client does not support sending a request with
-	// the CONNECT method. See the documentation on Transport for
-	// details.
-	Method string
-
-	// URL specifies either the URI being requested (for server
-	// requests) or the URL to access (for client requests).
-	//
-	// For server requests, the URL is parsed from the URI
-	// supplied on the Request-Line as stored in RequestURI.  For
-	// most requests, fields other than Path and RawQuery will be
-	// empty. (See RFC 7230, Section 5.3)
-	//
-	// For client requests, the URL's Host specifies the server to
-	// connect to, while the Request's Host field optionally
-	// specifies the Host header value to send in the HTTP
-	// request.
-	URL *url.URL
-
-	// The protocol version for incoming server requests.
-	//
-	// For client requests, these fields are ignored. The HTTP
-	// client code always uses either HTTP/1.1 or HTTP/2.
-	// See the docs on Transport for details.
-	Proto      string // "HTTP/1.0"
-	ProtoMajor int    // 1
-	ProtoMinor int    // 0
-
-	// Header contains the request header fields either received
-	// by the server or to be sent by the client.
-	//
-	// If a server received a request with header lines,
-	//
-	//	Host: example.com
-	//	accept-encoding: gzip, deflate
-	//	Accept-Language: en-us
-	//	fOO: Bar
-	//	foo: two
-	//
-	// then
-	//
-	//	Header = map[string][]string{
-	//		"Accept-Encoding": {"gzip, deflate"},
-	//		"Accept-Language": {"en-us"},
-	//		"Foo": {"Bar", "two"},
-	//	}
-	//
-	// For incoming requests, the Host header is promoted to the
-	// Request.Host field and removed from the Header map.
-	//
-	// HTTP defines that header names are case-insensitive. The
-	// request parser implements this by using CanonicalHeaderKey,
-	// making the first character and any characters following a
-	// hyphen uppercase and the rest lowercase.
-	//
-	// For client requests, certain headers such as Content-Length
-	// and Connection are automatically written when needed and
-	// values in Header may be ignored. See the documentation
-	// for the Request.Write method.
-	Header Header
-
-	// Body is the request's body.
-	//
-	// For client requests, a nil body means the request has no
-	// body, such as a GET request. The HTTP Client's Transport
-	// is responsible for calling the Close method.
-	//
-	// For server requests, the Request Body is always non-nil
-	// but will return EOF immediately when no body is present.
-	// The Server will close the request body. The ServeHTTP
-	// Handler does not need to.
-	//
-	// Body must allow Read to be called concurrently with Close.
-	// In particular, calling Close should unblock a Read waiting
-	// for input.
-	Body io.ReadCloser
-
-	// GetBody defines an optional func to return a new copy of
-	// Body. It is used for client requests when a redirect requires
-	// reading the body more than once. Use of GetBody still
-	// requires setting Body.
-	//
-	// For server requests, it is unused.
-	GetBody func() (io.ReadCloser, error)
-
-	// ContentLength records the length of the associated content.
-	// The value -1 indicates that the length is unknown.
-	// Values >= 0 indicate that the given number of bytes may
-	// be read from Body.
-	//
-	// For client requests, a value of 0 with a non-nil Body is
-	// also treated as unknown.
-	ContentLength int64
-
-	// TransferEncoding lists the transfer encodings from outermost to
-	// innermost. An empty list denotes the "identity" encoding.
-	// TransferEncoding can usually be ignored; chunked encoding is
-	// automatically added and removed as necessary when sending and
-	// receiving requests.
-	TransferEncoding []string
-
-	// Close indicates whether to close the connection after
-	// replying to this request (for servers) or after sending this
-	// request and reading its response (for clients).
-	//
-	// For server requests, the HTTP server handles this automatically
-	// and this field is not needed by Handlers.
-	//
-	// For client requests, setting this field prevents re-use of
-	// TCP connections between requests to the same hosts, as if
-	// Transport.DisableKeepAlives were set.
-	Close bool
-
-	// For server requests, Host specifies the host on which the
-	// URL is sought. For HTTP/1 (per RFC 7230, section 5.4), this
-	// is either the value of the "Host" header or the host name
-	// given in the URL itself. For HTTP/2, it is the value of the
-	// ":authority" pseudo-header field.
-	// It may be of the form "host:port". For international domain
-	// names, Host may be in Punycode or Unicode form. Use
-	// golang.org/x/net/idna to convert it to either format if
-	// needed.
-	// To prevent DNS rebinding attacks, server Handlers should
-	// validate that the Host header has a value for which the
-	// Handler considers itself authoritative. The included
-	// ServeMux supports patterns registered to particular host
-	// names and thus protects its registered Handlers.
-	//
-	// For client requests, Host optionally overrides the Host
-	// header to send. If empty, the Request.Write method uses
-	// the value of URL.Host. Host may contain an international
-	// domain name.
-	Host string
-
-	// Form contains the parsed form data, including both the URL
-	// field's query parameters and the PATCH, POST, or PUT form data.
-	// This field is only available after ParseForm is called.
-	// The HTTP client ignores Form and uses Body instead.
-	Form url.Values
-
-	// PostForm contains the parsed form data from PATCH, POST
-	// or PUT body parameters.
-	//
-	// This field is only available after ParseForm is called.
-	// The HTTP client ignores PostForm and uses Body instead.
-	PostForm url.Values
-
-	// MultipartForm is the parsed multipart form, including file uploads.
-	// This field is only available after ParseMultipartForm is called.
-	// The HTTP client ignores MultipartForm and uses Body instead.
-	MultipartForm *multipart.Form
-
-	// Trailer specifies additional headers that are sent after the request
-	// body.
-	//
-	// For server requests, the Trailer map initially contains only the
-	// trailer keys, with nil values. (The client declares which trailers it
-	// will later send.)  While the handler is reading from Body, it must
-	// not reference Trailer. After reading from Body returns EOF, Trailer
-	// can be read again and will contain non-nil values, if they were sent
-	// by the client.
-	//
-	// For client requests, Trailer must be initialized to a map containing
-	// the trailer keys to later send. The values may be nil or their final
-	// values. The ContentLength must be 0 or -1, to send a chunked request.
-	// After the HTTP request is sent the map values can be updated while
-	// the request body is read. Once the body returns EOF, the caller must
-	// not mutate Trailer.
-	//
-	// Few HTTP clients, servers, or proxies support HTTP trailers.
-	Trailer Header
-
-	// RemoteAddr allows HTTP servers and other software to record
-	// the network address that sent the request, usually for
-	// logging. This field is not filled in by ReadRequest and
-	// has no defined format. The HTTP server in this package
-	// sets RemoteAddr to an "IP:port" address before invoking a
-	// handler.
-	// This field is ignored by the HTTP client.
-	RemoteAddr string
-
-	// RequestURI is the unmodified request-target of the
-	// Request-Line (RFC 7230, Section 3.1.1) as sent by the client
-	// to a server. Usually the URL field should be used instead.
-	// It is an error to set this field in an HTTP client request.
-	RequestURI string
-
-	// TLS allows HTTP servers and other software to record
-	// information about the TLS connection on which the request
-	// was received. This field is not filled in by ReadRequest.
-	// The HTTP server in this package sets the field for
-	// TLS-enabled connections before invoking a handler;
-	// otherwise it leaves the field nil.
-	// This field is ignored by the HTTP client.
-	TLS *tls.ConnectionState
-
-	// Cancel is an optional channel whose closure indicates that the client
-	// request should be regarded as canceled. Not all implementations of
-	// RoundTripper may support Cancel.
-	//
-	// For server requests, this field is not applicable.
-	//
-	// Deprecated: Set the Request's context with NewRequestWithContext
-	// instead. If a Request's Cancel field and context are both
-	// set, it is undefined whether Cancel is respected.
-	Cancel <-chan struct{}
-
-	// Response is the redirect response which caused this request
-	// to be created. This field is only populated during client
-	// redirects.
-	Response *Response
-
-	// ctx is either the client or server context. It should only
-	// be modified via copying the whole Request using WithContext.
-	// It is unexported to prevent people from using Context wrong
-	// and mutating the contexts held by callers of the same request.
-	ctx context.Context
-}
-
-// Context returns the request's context. To change the context, use
-// WithContext.
-//
-// The returned context is always non-nil; it defaults to the
-// background context.
-//
-// For outgoing client requests, the context controls cancellation.
-//
-// For incoming server requests, the context is canceled when the
-// client's connection closes, the request is canceled (with HTTP/2),
-// or when the ServeHTTP method returns.
-func (r *Request) Context() context.Context {
-	if r.ctx != nil {
-		return r.ctx
-	}
-	return context.Background()
-}
-
-// WithContext returns a shallow copy of r with its context changed
-// to ctx. The provided ctx must be non-nil.
-//
-// For outgoing client request, the context controls the entire
-// lifetime of a request and its response: obtaining a connection,
-// sending the request, and reading the response headers and body.
-//
-// To create a new request with a context, use NewRequestWithContext.
-// To change the context of a request, such as an incoming request you
-// want to modify before sending back out, use Request.Clone. Between
-// those two uses, it's rare to need WithContext.
-func (r *Request) WithContext(ctx context.Context) *Request {
-	if ctx == nil {
-		panic("nil context")
-	}
-	r2 := new(Request)
-	*r2 = *r
-	r2.ctx = ctx
-	r2.URL = cloneURL(r.URL) // legacy behavior; TODO: try to remove. Issue 23544
-	return r2
-}
-
-// Clone returns a deep copy of r with its context changed to ctx.
-// The provided ctx must be non-nil.
-//
-// For an outgoing client request, the context controls the entire
-// lifetime of a request and its response: obtaining a connection,
-// sending the request, and reading the response headers and body.
-func (r *Request) Clone(ctx context.Context) *Request {
-	if ctx == nil {
-		panic("nil context")
-	}
-	r2 := new(Request)
-	*r2 = *r
-	r2.ctx = ctx
-	r2.URL = cloneURL(r.URL)
-	if r.Header != nil {
-		r2.Header = r.Header.Clone()
-	}
-	if r.Trailer != nil {
-		r2.Trailer = r.Trailer.Clone()
-	}
-	if s := r.TransferEncoding; s != nil {
-		s2 := make([]string, len(s))
-		copy(s2, s)
-		r2.TransferEncoding = s2
-	}
-	r2.Form = cloneURLValues(r.Form)
-	r2.PostForm = cloneURLValues(r.PostForm)
-	r2.MultipartForm = cloneMultipartForm(r.MultipartForm)
-	return r2
-}
-
-// ProtoAtLeast reports whether the HTTP protocol used
-// in the request is at least major.minor.
-func (r *Request) ProtoAtLeast(major, minor int) bool {
-	return r.ProtoMajor > major ||
-		r.ProtoMajor == major && r.ProtoMinor >= minor
-}
-
-// UserAgent returns the client's User-Agent, if sent in the request.
-func (r *Request) UserAgent() string {
-	return r.Header.Get("User-Agent")
-}
-
-// Cookies parses and returns the HTTP cookies sent with the request.
-func (r *Request) Cookies() []*Cookie {
-	return readCookies(r.Header, "")
-}
-
-// ErrNoCookie is returned by Request's Cookie method when a cookie is not found.
-var ErrNoCookie = errors.New("http: named cookie not present")
-
-// Cookie returns the named cookie provided in the request or
-// ErrNoCookie if not found.
-// If multiple cookies match the given name, only one cookie will
-// be returned.
-func (r *Request) Cookie(name string) (*Cookie, error) {
-	for _, c := range readCookies(r.Header, name) {
-		return c, nil
-	}
-	return nil, ErrNoCookie
-}
-
-// AddCookie adds a cookie to the request. Per RFC 6265 section 5.4,
-// AddCookie does not attach more than one Cookie header field. That
-// means all cookies, if any, are written into the same line,
-// separated by semicolon.
-// AddCookie only sanitizes c's name and value, and does not sanitize
-// a Cookie header already present in the request.
-func (r *Request) AddCookie(c *Cookie) {
-	s := fmt.Sprintf("%s=%s", sanitizeCookieName(c.Name), sanitizeCookieValue(c.Value))
-	if c := r.Header.Get("Cookie"); c != "" {
-		r.Header.Set("Cookie", c+"; "+s)
-	} else {
-		r.Header.Set("Cookie", s)
-	}
-}
-
-// Referer returns the referring URL, if sent in the request.
-//
-// Referer is misspelled as in the request itself, a mistake from the
-// earliest days of HTTP.  This value can also be fetched from the
-// Header map as Header["Referer"]; the benefit of making it available
-// as a method is that the compiler can diagnose programs that use the
-// alternate (correct English) spelling req.Referrer() but cannot
-// diagnose programs that use Header["Referrer"].
-func (r *Request) Referer() string {
-	return r.Header.Get("Referer")
-}
-
-// multipartByReader is a sentinel value.
-// Its presence in Request.MultipartForm indicates that parsing of the request
-// body has been handed off to a MultipartReader instead of ParseMultipartForm.
-var multipartByReader = &multipart.Form{
-	Value: make(map[string][]string),
-	File:  make(map[string][]*multipart.FileHeader),
-}
-
-// MultipartReader returns a MIME multipart reader if this is a
-// multipart/form-data or a multipart/mixed POST request, else returns nil and an error.
-// Use this function instead of ParseMultipartForm to
-// process the request body as a stream.
-func (r *Request) MultipartReader() (*multipart.Reader, error) {
-	if r.MultipartForm == multipartByReader {
-		return nil, errors.New("http: MultipartReader called twice")
-	}
-	if r.MultipartForm != nil {
-		return nil, errors.New("http: multipart handled by ParseMultipartForm")
-	}
-	r.MultipartForm = multipartByReader
-	return r.multipartReader(true)
-}
-
-func (r *Request) multipartReader(allowMixed bool) (*multipart.Reader, error) {
-	v := r.Header.Get("Content-Type")
-	if v == "" {
-		return nil, ErrNotMultipart
-	}
-	d, params, err := mime.ParseMediaType(v)
-	if err != nil || !(d == "multipart/form-data" || allowMixed && d == "multipart/mixed") {
-		return nil, ErrNotMultipart
-	}
-	boundary, ok := params["boundary"]
-	if !ok {
-		return nil, ErrMissingBoundary
-	}
-	return multipart.NewReader(r.Body, boundary), nil
-}
-
-// isH2Upgrade reports whether r represents the http2 "client preface"
-// magic string.
-func (r *Request) isH2Upgrade() bool {
-	return r.Method == "PRI" && len(r.Header) == 0 && r.URL.Path == "*" && r.Proto == "HTTP/2.0"
-}
-
-// Return value if nonempty, def otherwise.
-func valueOrDefault(value, def string) string {
-	if value != "" {
-		return value
-	}
-	return def
-}
-
-// NOTE: This is not intended to reflect the actual Go version being used.
-// It was changed at the time of Go 1.1 release because the former User-Agent
-// had ended up blocked by some intrusion detection systems.
-// See https://codereview.appspot.com/7532043.
-const defaultUserAgent = "Go-http-client/1.1"
-
-// Write writes an HTTP/1.1 request, which is the header and body, in wire format.
-// This method consults the following fields of the request:
-//	Host
-//	URL
-//	Method (defaults to "GET")
-//	Header
-//	ContentLength
-//	TransferEncoding
-//	Body
-//
-// If Body is present, Content-Length is <= 0 and TransferEncoding
-// hasn't been set to "identity", Write adds "Transfer-Encoding:
-// chunked" to the header. Body is closed after it is sent.
-func (r *Request) Write(w io.Writer) error {
-	return r.write(w, false, nil, nil)
-}
-
-// WriteProxy is like Write but writes the request in the form
-// expected by an HTTP proxy. In particular, WriteProxy writes the
-// initial Request-URI line of the request with an absolute URI, per
-// section 5.3 of RFC 7230, including the scheme and host.
-// In either case, WriteProxy also writes a Host header, using
-// either r.Host or r.URL.Host.
-func (r *Request) WriteProxy(w io.Writer) error {
-	return r.write(w, true, nil, nil)
-}
-
-// errMissingHost is returned by Write when there is no Host or URL present in
-// the Request.
-var errMissingHost = errors.New("http: Request.Write on Request with no Host or URL set")
-
-// extraHeaders may be nil
-// waitForContinue may be nil
-// always closes body
-func (r *Request) write(w io.Writer, usingProxy bool, extraHeaders Header, waitForContinue func() bool) (err error) {
-	trace := httptrace.ContextClientTrace(r.Context())
-	if trace != nil && trace.WroteRequest != nil {
-		defer func() {
-			trace.WroteRequest(httptrace.WroteRequestInfo{
-				Err: err,
-			})
-		}()
-	}
-	closed := false
-	defer func() {
-		if closed {
-			return
-		}
-		if closeErr := r.closeBody(); closeErr != nil && err == nil {
-			err = closeErr
-		}
-	}()
-
-	// Find the target host. Prefer the Host: header, but if that
-	// is not given, use the host from the request URL.
-	//
-	// Clean the host, in case it arrives with unexpected stuff in it.
-	host := cleanHost(r.Host)
-	if host == "" {
-		if r.URL == nil {
-			return errMissingHost
-		}
-		host = cleanHost(r.URL.Host)
-	}
-
-	// According to RFC 6874, an HTTP client, proxy, or other
-	// intermediary must remove any IPv6 zone identifier attached
-	// to an outgoing URI.
-	host = removeZone(host)
-
-	ruri := r.URL.RequestURI()
-	if usingProxy && r.URL.Scheme != "" && r.URL.Opaque == "" {
-		ruri = r.URL.Scheme + "://" + host + ruri
-	} else if r.Method == "CONNECT" && r.URL.Path == "" {
-		// CONNECT requests normally give just the host and port, not a full URL.
-		ruri = host
-		if r.URL.Opaque != "" {
-			ruri = r.URL.Opaque
-		}
-	}
-	if stringContainsCTLByte(ruri) {
-		return errors.New("net/http: can't write control character in Request.URL")
-	}
-	// TODO: validate r.Method too? At least it's less likely to
-	// come from an attacker (more likely to be a constant in
-	// code).
-
-	// Wrap the writer in a bufio Writer if it's not already buffered.
-	// Don't always call NewWriter, as that forces a bytes.Buffer
-	// and other small bufio Writers to have a minimum 4k buffer
-	// size.
-	var bw *bufio.Writer
-	if _, ok := w.(io.ByteWriter); !ok {
-		bw = bufio.NewWriter(w)
-		w = bw
-	}
-
-	_, err = fmt.Fprintf(w, "%s %s HTTP/1.1\r\n", valueOrDefault(r.Method, "GET"), ruri)
-	if err != nil {
-		return err
-	}
-
-	// Header lines
-	_, err = fmt.Fprintf(w, "Host: %s\r\n", host)
-	if err != nil {
-		return err
-	}
-	if trace != nil && trace.WroteHeaderField != nil {
-		trace.WroteHeaderField("Host", []string{host})
-	}
-
-	// Use the defaultUserAgent unless the Header contains one, which
-	// may be blank to not send the header.
-	userAgent := defaultUserAgent
-	if r.Header.has("User-Agent") {
-		userAgent = r.Header.Get("User-Agent")
-	}
-	if userAgent != "" {
-		_, err = fmt.Fprintf(w, "User-Agent: %s\r\n", userAgent)
-		if err != nil {
-			return err
-		}
-		if trace != nil && trace.WroteHeaderField != nil {
-			trace.WroteHeaderField("User-Agent", []string{userAgent})
-		}
-	}
-
-	// Process Body,ContentLength,Close,Trailer
-	tw, err := newTransferWriter(r)
-	if err != nil {
-		return err
-	}
-	err = tw.writeHeader(w, trace)
-	if err != nil {
-		return err
-	}
-
-	err = r.Header.writeSubset(w, reqWriteExcludeHeader, trace)
-	if err != nil {
-		return err
-	}
-
-	if extraHeaders != nil {
-		err = extraHeaders.write(w, trace)
-		if err != nil {
-			return err
-		}
-	}
-
-	_, err = io.WriteString(w, "\r\n")
-	if err != nil {
-		return err
-	}
-
-	if trace != nil && trace.WroteHeaders != nil {
-		trace.WroteHeaders()
-	}
-
-	// Flush and wait for 100-continue if expected.
-	if waitForContinue != nil {
-		if bw, ok := w.(*bufio.Writer); ok {
-			err = bw.Flush()
-			if err != nil {
-				return err
-			}
-		}
-		if trace != nil && trace.Wait100Continue != nil {
-			trace.Wait100Continue()
-		}
-		if !waitForContinue() {
-			closed = true
-			r.closeBody()
-			return nil
-		}
-	}
-
-	if bw, ok := w.(*bufio.Writer); ok && tw.FlushHeaders {
-		if err := bw.Flush(); err != nil {
-			return err
-		}
-	}
-
-	// Write body and trailer
-	closed = true
-	err = tw.writeBody(w)
-	if err != nil {
-		if tw.bodyReadError == err {
-			err = requestBodyReadError{err}
-		}
-		return err
-	}
-
-	if bw != nil {
-		return bw.Flush()
-	}
-	return nil
-}
-
-// requestBodyReadError wraps an error from (*Request).write to indicate
-// that the error came from a Read call on the Request.Body.
-// This error type should not escape the net/http package to users.
-type requestBodyReadError struct{ error }
-
-func idnaASCII(v string) (string, error) {
-	// TODO: Consider removing this check after verifying performance is okay.
-	// Right now punycode verification, length checks, context checks, and the
-	// permissible character tests are all omitted. It also prevents the ToASCII
-	// call from salvaging an invalid IDN, when possible. As a result it may be
-	// possible to have two IDNs that appear identical to the user where the
-	// ASCII-only version causes an error downstream whereas the non-ASCII
-	// version does not.
-	// Note that for correct ASCII IDNs ToASCII will only do considerably more
-	// work, but it will not cause an allocation.
-	if ascii.Is(v) {
-		return v, nil
-	}
-	return idna.Lookup.ToASCII(v)
-}
-
-// cleanHost cleans up the host sent in request's Host header.
-//
-// It both strips anything after '/' or ' ', and puts the value
-// into Punycode form, if necessary.
-//
-// Ideally we'd clean the Host header according to the spec:
-//   https://tools.ietf.org/html/rfc7230#section-5.4 (Host = uri-host [ ":" port ]")
-//   https://tools.ietf.org/html/rfc7230#section-2.7 (uri-host -> rfc3986's host)
-//   https://tools.ietf.org/html/rfc3986#section-3.2.2 (definition of host)
-// But practically, what we are trying to avoid is the situation in
-// issue 11206, where a malformed Host header used in the proxy context
-// would create a bad request. So it is enough to just truncate at the
-// first offending character.
-func cleanHost(in string) string {
-	if i := strings.IndexAny(in, " /"); i != -1 {
-		in = in[:i]
-	}
-	host, port, err := net.SplitHostPort(in)
-	if err != nil { // input was just a host
-		a, err := idnaASCII(in)
-		if err != nil {
-			return in // garbage in, garbage out
-		}
-		return a
-	}
-	a, err := idnaASCII(host)
-	if err != nil {
-		return in // garbage in, garbage out
-	}
-	return net.JoinHostPort(a, port)
-}
-
-// removeZone removes IPv6 zone identifier from host.
-// E.g., "[fe80::1%en0]:8080" to "[fe80::1]:8080"
-func removeZone(host string) string {
-	if !strings.HasPrefix(host, "[") {
-		return host
-	}
-	i := strings.LastIndex(host, "]")
-	if i < 0 {
-		return host
-	}
-	j := strings.LastIndex(host[:i], "%")
-	if j < 0 {
-		return host
-	}
-	return host[:j] + host[i:]
-}
-
-// ParseHTTPVersion parses an HTTP version string according to RFC 7230, section 2.6.
-// "HTTP/1.0" returns (1, 0, true). Note that strings without
-// a minor version, such as "HTTP/2", are not valid.
-func ParseHTTPVersion(vers string) (major, minor int, ok bool) {
-	switch vers {
-	case "HTTP/1.1":
-		return 1, 1, true
-	case "HTTP/1.0":
-		return 1, 0, true
-	}
-	if !strings.HasPrefix(vers, "HTTP/") {
-		return 0, 0, false
-	}
-	if len(vers) != len("HTTP/X.Y") {
-		return 0, 0, false
-	}
-	if vers[6] != '.' {
-		return 0, 0, false
-	}
-	maj, err := strconv.ParseUint(vers[5:6], 10, 0)
-	if err != nil {
-		return 0, 0, false
-	}
-	min, err := strconv.ParseUint(vers[7:8], 10, 0)
-	if err != nil {
-		return 0, 0, false
-	}
-	return int(maj), int(min), true
-}
-
-func validMethod(method string) bool {
-	/*
-	     Method         = "OPTIONS"                ; Section 9.2
-	                    | "GET"                    ; Section 9.3
-	                    | "HEAD"                   ; Section 9.4
-	                    | "POST"                   ; Section 9.5
-	                    | "PUT"                    ; Section 9.6
-	                    | "DELETE"                 ; Section 9.7
-	                    | "TRACE"                  ; Section 9.8
-	                    | "CONNECT"                ; Section 9.9
-	                    | extension-method
-	   extension-method = token
-	     token          = 1*<any CHAR except CTLs or separators>
-	*/
-	return len(method) > 0 && strings.IndexFunc(method, isNotToken) == -1
-}
-
-// NewRequest wraps NewRequestWithContext using context.Background.
-func NewRequest(method, url string, body io.Reader) (*Request, error) {
-	return NewRequestWithContext(context.Background(), method, url, body)
-}
-
-// NewRequestWithContext returns a new Request given a method, URL, and
-// optional body.
-//
-// If the provided body is also an io.Closer, the returned
-// Request.Body is set to body and will be closed by the Client
-// methods Do, Post, and PostForm, and Transport.RoundTrip.
-//
-// NewRequestWithContext returns a Request suitable for use with
-// Client.Do or Transport.RoundTrip. To create a request for use with
-// testing a Server Handler, either use the NewRequest function in the
-// net/http/httptest package, use ReadRequest, or manually update the
-// Request fields. For an outgoing client request, the context
-// controls the entire lifetime of a request and its response:
-// obtaining a connection, sending the request, and reading the
-// response headers and body. See the Request type's documentation for
-// the difference between inbound and outbound request fields.
-//
-// If body is of type *bytes.Buffer, *bytes.Reader, or
-// *strings.Reader, the returned request's ContentLength is set to its
-// exact value (instead of -1), GetBody is populated (so 307 and 308
-// redirects can replay the body), and Body is set to NoBody if the
-// ContentLength is 0.
-func NewRequestWithContext(ctx context.Context, method, url string, body io.Reader) (*Request, error) {
-	if method == "" {
-		// We document that "" means "GET" for Request.Method, and people have
-		// relied on that from NewRequest, so keep that working.
-		// We still enforce validMethod for non-empty methods.
-		method = "GET"
-	}
-	if !validMethod(method) {
-		return nil, fmt.Errorf("net/http: invalid method %q", method)
-	}
-	if ctx == nil {
-		return nil, errors.New("net/http: nil Context")
-	}
-	u, err := urlpkg.Parse(url)
-	if err != nil {
-		return nil, err
-	}
-	rc, ok := body.(io.ReadCloser)
-	if !ok && body != nil {
-		rc = io.NopCloser(body)
-	}
-	// The host's colon:port should be normalized. See Issue 14836.
-	u.Host = removeEmptyPort(u.Host)
-	req := &Request{
-		ctx:        ctx,
-		Method:     method,
-		URL:        u,
-		Proto:      "HTTP/1.1",
-		ProtoMajor: 1,
-		ProtoMinor: 1,
-		Header:     make(Header),
-		Body:       rc,
-		Host:       u.Host,
-	}
-	if body != nil {
-		switch v := body.(type) {
-		case *bytes.Buffer:
-			req.ContentLength = int64(v.Len())
-			buf := v.Bytes()
-			req.GetBody = func() (io.ReadCloser, error) {
-				r := bytes.NewReader(buf)
-				return io.NopCloser(r), nil
-			}
-		case *bytes.Reader:
-			req.ContentLength = int64(v.Len())
-			snapshot := *v
-			req.GetBody = func() (io.ReadCloser, error) {
-				r := snapshot
-				return io.NopCloser(&r), nil
-			}
-		case *strings.Reader:
-			req.ContentLength = int64(v.Len())
-			snapshot := *v
-			req.GetBody = func() (io.ReadCloser, error) {
-				r := snapshot
-				return io.NopCloser(&r), nil
-			}
-		default:
-			// This is where we'd set it to -1 (at least
-			// if body != NoBody) to mean unknown, but
-			// that broke people during the Go 1.8 testing
-			// period. People depend on it being 0 I
-			// guess. Maybe retry later. See Issue 18117.
-		}
-		// For client requests, Request.ContentLength of 0
-		// means either actually 0, or unknown. The only way
-		// to explicitly say that the ContentLength is zero is
-		// to set the Body to nil. But turns out too much code
-		// depends on NewRequest returning a non-nil Body,
-		// so we use a well-known ReadCloser variable instead
-		// and have the http package also treat that sentinel
-		// variable to mean explicitly zero.
-		if req.GetBody != nil && req.ContentLength == 0 {
-			req.Body = NoBody
-			req.GetBody = func() (io.ReadCloser, error) { return NoBody, nil }
-		}
-	}
-
-	return req, nil
-}
-
-// BasicAuth returns the username and password provided in the request's
-// Authorization header, if the request uses HTTP Basic Authentication.
-// See RFC 2617, Section 2.
-func (r *Request) BasicAuth() (username, password string, ok bool) {
-	auth := r.Header.Get("Authorization")
-	if auth == "" {
-		return "", "", false
-	}
-	return parseBasicAuth(auth)
-}
-
-// parseBasicAuth parses an HTTP Basic Authentication string.
-// "Basic QWxhZGRpbjpvcGVuIHNlc2FtZQ==" returns ("Aladdin", "open sesame", true).
-func parseBasicAuth(auth string) (username, password string, ok bool) {
-	const prefix = "Basic "
-	// Case insensitive prefix match. See Issue 22736.
-	if len(auth) < len(prefix) || !ascii.EqualFold(auth[:len(prefix)], prefix) {
-		return "", "", false
-	}
-	c, err := base64.StdEncoding.DecodeString(auth[len(prefix):])
-	if err != nil {
-		return "", "", false
-	}
-	cs := string(c)
-	username, password, ok = strings.Cut(cs, ":")
-	if !ok {
-		return "", "", false
-	}
-	return username, password, true
-}
-
-// SetBasicAuth sets the request's Authorization header to use HTTP
-// Basic Authentication with the provided username and password.
-//
-// With HTTP Basic Authentication the provided username and password
-// are not encrypted.
-//
-// Some protocols may impose additional requirements on pre-escaping the
-// username and password. For instance, when used with OAuth2, both arguments
-// must be URL encoded first with url.QueryEscape.
-func (r *Request) SetBasicAuth(username, password string) {
-	r.Header.Set("Authorization", "Basic "+basicAuth(username, password))
-}
-
-// parseRequestLine parses "GET /foo HTTP/1.1" into its three parts.
-func parseRequestLine(line string) (method, requestURI, proto string, ok bool) {
-	method, rest, ok1 := strings.Cut(line, " ")
-	requestURI, proto, ok2 := strings.Cut(rest, " ")
-	if !ok1 || !ok2 {
-		return "", "", "", false
-	}
-	return method, requestURI, proto, true
-}
-
-var textprotoReaderPool sync.Pool
-
-func newTextprotoReader(br *bufio.Reader) *textproto.Reader {
-	if v := textprotoReaderPool.Get(); v != nil {
-		tr := v.(*textproto.Reader)
-		tr.R = br
-		return tr
-	}
-	return textproto.NewReader(br)
-}
-
-func putTextprotoReader(r *textproto.Reader) {
-	r.R = nil
-	textprotoReaderPool.Put(r)
-}
-
-// ReadRequest reads and parses an incoming request from b.
-//
-// ReadRequest is a low-level function and should only be used for
-// specialized applications; most code should use the Server to read
-// requests and handle them via the Handler interface. ReadRequest
-// only supports HTTP/1.x requests. For HTTP/2, use golang.org/x/net/http2.
-func ReadRequest(b *bufio.Reader) (*Request, error) {
-	req, err := readRequest(b)
-	if err != nil {
-		return nil, err
-	}
-
-	delete(req.Header, "Host")
-	return req, err
-}
-
-func readRequest(b *bufio.Reader) (req *Request, err error) {
-	tp := newTextprotoReader(b)
-	req = new(Request)
-
-	// First line: GET /index.html HTTP/1.0
-	var s string
-	if s, err = tp.ReadLine(); err != nil {
-		return nil, err
-	}
-	defer func() {
-		putTextprotoReader(tp)
-		if err == io.EOF {
-			err = io.ErrUnexpectedEOF
-		}
-	}()
-
-	var ok bool
-	req.Method, req.RequestURI, req.Proto, ok = parseRequestLine(s)
-	if !ok {
-		return nil, badStringError("malformed HTTP request", s)
-	}
-	if !validMethod(req.Method) {
-		return nil, badStringError("invalid method", req.Method)
-	}
-	rawurl := req.RequestURI
-	if req.ProtoMajor, req.ProtoMinor, ok = ParseHTTPVersion(req.Proto); !ok {
-		return nil, badStringError("malformed HTTP version", req.Proto)
-	}
-
-	// CONNECT requests are used two different ways, and neither uses a full URL:
-	// The standard use is to tunnel HTTPS through an HTTP proxy.
-	// It looks like "CONNECT www.google.com:443 HTTP/1.1", and the parameter is
-	// just the authority section of a URL. This information should go in req.URL.Host.
-	//
-	// The net/rpc package also uses CONNECT, but there the parameter is a path
-	// that starts with a slash. It can be parsed with the regular URL parser,
-	// and the path will end up in req.URL.Path, where it needs to be in order for
-	// RPC to work.
-	justAuthority := req.Method == "CONNECT" && !strings.HasPrefix(rawurl, "/")
-	if justAuthority {
-		rawurl = "http://" + rawurl
-	}
-
-	if req.URL, err = url.ParseRequestURI(rawurl); err != nil {
-		return nil, err
-	}
-
-	if justAuthority {
-		// Strip the bogus "http://" back off.
-		req.URL.Scheme = ""
-	}
-
-	// Subsequent lines: Key: value.
-	mimeHeader, err := tp.ReadMIMEHeader()
-	if err != nil {
-		return nil, err
-	}
-	req.Header = Header(mimeHeader)
-	if len(req.Header["Host"]) > 1 {
-		return nil, fmt.Errorf("too many Host headers")
-	}
-
-	// RFC 7230, section 5.3: Must treat
-	//	GET /index.html HTTP/1.1
-	//	Host: www.google.com
-	// and
-	//	GET http://www.google.com/index.html HTTP/1.1
-	//	Host: doesntmatter
-	// the same. In the second case, any Host line is ignored.
-	req.Host = req.URL.Host
-	if req.Host == "" {
-		req.Host = req.Header.get("Host")
-	}
-
-	fixPragmaCacheControl(req.Header)
-
-	req.Close = shouldClose(req.ProtoMajor, req.ProtoMinor, req.Header, false)
-
-	err = readTransfer(req, b)
-	if err != nil {
-		return nil, err
-	}
-
-	if req.isH2Upgrade() {
-		// Because it's neither chunked, nor declared:
-		req.ContentLength = -1
-
-		// We want to give handlers a chance to hijack the
-		// connection, but we need to prevent the Server from
-		// dealing with the connection further if it's not
-		// hijacked. Set Close to ensure that:
-		req.Close = true
-	}
-	return req, nil
-}
-
-// MaxBytesReader is similar to io.LimitReader but is intended for
-// limiting the size of incoming request bodies. In contrast to
-// io.LimitReader, MaxBytesReader's result is a ReadCloser, returns a
-// non-EOF error for a Read beyond the limit, and closes the
-// underlying reader when its Close method is called.
-//
-// MaxBytesReader prevents clients from accidentally or maliciously
-// sending a large request and wasting server resources.
-func MaxBytesReader(w ResponseWriter, r io.ReadCloser, n int64) io.ReadCloser {
-	if n < 0 { // Treat negative limits as equivalent to 0.
-		n = 0
-	}
-	return &maxBytesReader{w: w, r: r, n: n}
-}
-
-type maxBytesReader struct {
-	w   ResponseWriter
-	r   io.ReadCloser // underlying reader
-	n   int64         // max bytes remaining
-	err error         // sticky error
-}
-
-func (l *maxBytesReader) Read(p []byte) (n int, err error) {
-	if l.err != nil {
-		return 0, l.err
-	}
-	if len(p) == 0 {
-		return 0, nil
-	}
-	// If they asked for a 32KB byte read but only 5 bytes are
-	// remaining, no need to read 32KB. 6 bytes will answer the
-	// question of the whether we hit the limit or go past it.
-	if int64(len(p)) > l.n+1 {
-		p = p[:l.n+1]
-	}
-	n, err = l.r.Read(p)
-
-	if int64(n) <= l.n {
-		l.n -= int64(n)
-		l.err = err
-		return n, err
-	}
-
-	n = int(l.n)
-	l.n = 0
-
-	// The server code and client code both use
-	// maxBytesReader. This "requestTooLarge" check is
-	// only used by the server code. To prevent binaries
-	// which only using the HTTP Client code (such as
-	// cmd/go) from also linking in the HTTP server, don't
-	// use a static type assertion to the server
-	// "*response" type. Check this interface instead:
-	type requestTooLarger interface {
-		requestTooLarge()
-	}
-	if res, ok := l.w.(requestTooLarger); ok {
-		res.requestTooLarge()
-	}
-	l.err = errors.New("http: request body too large")
-	return n, l.err
-}
-
-func (l *maxBytesReader) Close() error {
-	return l.r.Close()
-}
-
-func copyValues(dst, src url.Values) {
-	for k, vs := range src {
-		dst[k] = append(dst[k], vs...)
-	}
-}
-
-func parsePostForm(r *Request) (vs url.Values, err error) {
-	if r.Body == nil {
-		err = errors.New("missing form body")
-		return
-	}
-	ct := r.Header.Get("Content-Type")
-	// RFC 7231, section 3.1.1.5 - empty type
-	//   MAY be treated as application/octet-stream
-	if ct == "" {
-		ct = "application/octet-stream"
-	}
-	ct, _, err = mime.ParseMediaType(ct)
-	switch {
-	case ct == "application/x-www-form-urlencoded":
-		var reader io.Reader = r.Body
-		maxFormSize := int64(1<<63 - 1)
-		if _, ok := r.Body.(*maxBytesReader); !ok {
-			maxFormSize = int64(10 << 20) // 10 MB is a lot of text.
-			reader = io.LimitReader(r.Body, maxFormSize+1)
-		}
-		b, e := io.ReadAll(reader)
-		if e != nil {
-			if err == nil {
-				err = e
-			}
-			break
-		}
-		if int64(len(b)) > maxFormSize {
-			err = errors.New("http: POST too large")
-			return
-		}
-		vs, e = url.ParseQuery(string(b))
-		if err == nil {
-			err = e
-		}
-	case ct == "multipart/form-data":
-		// handled by ParseMultipartForm (which is calling us, or should be)
-		// TODO(bradfitz): there are too many possible
-		// orders to call too many functions here.
-		// Clean this up and write more tests.
-		// request_test.go contains the start of this,
-		// in TestParseMultipartFormOrder and others.
-	}
-	return
-}
-
-// ParseForm populates r.Form and r.PostForm.
-//
-// For all requests, ParseForm parses the raw query from the URL and updates
-// r.Form.
-//
-// For POST, PUT, and PATCH requests, it also reads the request body, parses it
-// as a form and puts the results into both r.PostForm and r.Form. Request body
-// parameters take precedence over URL query string values in r.Form.
-//
-// If the request Body's size has not already been limited by MaxBytesReader,
-// the size is capped at 10MB.
-//
-// For other HTTP methods, or when the Content-Type is not
-// application/x-www-form-urlencoded, the request Body is not read, and
-// r.PostForm is initialized to a non-nil, empty value.
-//
-// ParseMultipartForm calls ParseForm automatically.
-// ParseForm is idempotent.
-func (r *Request) ParseForm() error {
-	var err error
-	if r.PostForm == nil {
-		if r.Method == "POST" || r.Method == "PUT" || r.Method == "PATCH" {
-			r.PostForm, err = parsePostForm(r)
-		}
-		if r.PostForm == nil {
-			r.PostForm = make(url.Values)
-		}
-	}
-	if r.Form == nil {
-		if len(r.PostForm) > 0 {
-			r.Form = make(url.Values)
-			copyValues(r.Form, r.PostForm)
-		}
-		var newValues url.Values
-		if r.URL != nil {
-			var e error
-			newValues, e = url.ParseQuery(r.URL.RawQuery)
-			if err == nil {
-				err = e
-			}
-		}
-		if newValues == nil {
-			newValues = make(url.Values)
-		}
-		if r.Form == nil {
-			r.Form = newValues
-		} else {
-			copyValues(r.Form, newValues)
-		}
-	}
-	return err
-}
-
-// ParseMultipartForm parses a request body as multipart/form-data.
-// The whole request body is parsed and up to a total of maxMemory bytes of
-// its file parts are stored in memory, with the remainder stored on
-// disk in temporary files.
-// ParseMultipartForm calls ParseForm if necessary.
-// If ParseForm returns an error, ParseMultipartForm returns it but also
-// continues parsing the request body.
-// After one call to ParseMultipartForm, subsequent calls have no effect.
-func (r *Request) ParseMultipartForm(maxMemory int64) error {
-	if r.MultipartForm == multipartByReader {
-		return errors.New("http: multipart handled by MultipartReader")
-	}
-	var parseFormErr error
-	if r.Form == nil {
-		// Let errors in ParseForm fall through, and just
-		// return it at the end.
-		parseFormErr = r.ParseForm()
-	}
-	if r.MultipartForm != nil {
-		return nil
-	}
-
-	mr, err := r.multipartReader(false)
-	if err != nil {
-		return err
-	}
-
-	f, err := mr.ReadForm(maxMemory)
-	if err != nil {
-		return err
-	}
-
-	if r.PostForm == nil {
-		r.PostForm = make(url.Values)
-	}
-	for k, v := range f.Value {
-		r.Form[k] = append(r.Form[k], v...)
-		// r.PostForm should also be populated. See Issue 9305.
-		r.PostForm[k] = append(r.PostForm[k], v...)
-	}
-
-	r.MultipartForm = f
-
-	return parseFormErr
-}
-
-// FormValue returns the first value for the named component of the query.
-// POST and PUT body parameters take precedence over URL query string values.
-// FormValue calls ParseMultipartForm and ParseForm if necessary and ignores
-// any errors returned by these functions.
-// If key is not present, FormValue returns the empty string.
-// To access multiple values of the same key, call ParseForm and
-// then inspect Request.Form directly.
-func (r *Request) FormValue(key string) string {
-	if r.Form == nil {
-		r.ParseMultipartForm(defaultMaxMemory)
-	}
-	if vs := r.Form[key]; len(vs) > 0 {
-		return vs[0]
-	}
-	return ""
-}
-
-// PostFormValue returns the first value for the named component of the POST,
-// PATCH, or PUT request body. URL query parameters are ignored.
-// PostFormValue calls ParseMultipartForm and ParseForm if necessary and ignores
-// any errors returned by these functions.
-// If key is not present, PostFormValue returns the empty string.
-func (r *Request) PostFormValue(key string) string {
-	if r.PostForm == nil {
-		r.ParseMultipartForm(defaultMaxMemory)
-	}
-	if vs := r.PostForm[key]; len(vs) > 0 {
-		return vs[0]
-	}
-	return ""
-}
-
-// FormFile returns the first file for the provided form key.
-// FormFile calls ParseMultipartForm and ParseForm if necessary.
-func (r *Request) FormFile(key string) (multipart.File, *multipart.FileHeader, error) {
-	if r.MultipartForm == multipartByReader {
-		return nil, nil, errors.New("http: multipart handled by MultipartReader")
-	}
-	if r.MultipartForm == nil {
-		err := r.ParseMultipartForm(defaultMaxMemory)
-		if err != nil {
-			return nil, nil, err
-		}
-	}
-	if r.MultipartForm != nil && r.MultipartForm.File != nil {
-		if fhs := r.MultipartForm.File[key]; len(fhs) > 0 {
-			f, err := fhs[0].Open()
-			return f, fhs[0], err
-		}
-	}
-	return nil, nil, ErrMissingFile
-}
-
-func (r *Request) expectsContinue() bool {
-	return hasToken(r.Header.get("Expect"), "100-continue")
-}
-
-func (r *Request) wantsHttp10KeepAlive() bool {
-	if r.ProtoMajor != 1 || r.ProtoMinor != 0 {
-		return false
-	}
-	return hasToken(r.Header.get("Connection"), "keep-alive")
-}
-
-func (r *Request) wantsClose() bool {
-	if r.Close {
-		return true
-	}
-	return hasToken(r.Header.get("Connection"), "close")
-}
-
-func (r *Request) closeBody() error {
-	if r.Body == nil {
-		return nil
-	}
-	return r.Body.Close()
-}
-
-func (r *Request) isReplayable() bool {
-	if r.Body == nil || r.Body == NoBody || r.GetBody != nil {
-		switch valueOrDefault(r.Method, "GET") {
-		case "GET", "HEAD", "OPTIONS", "TRACE":
-			return true
-		}
-		// The Idempotency-Key, while non-standard, is widely used to
-		// mean a POST or other request is idempotent. See
-		// https://golang.org/issue/19943#issuecomment-421092421
-		if r.Header.has("Idempotency-Key") || r.Header.has("X-Idempotency-Key") {
-			return true
-		}
-	}
-	return false
-}
-
-// outgoingLength reports the Content-Length of this outgoing (Client) request.
-// It maps 0 into -1 (unknown) when the Body is non-nil.
-func (r *Request) outgoingLength() int64 {
-	if r.Body == nil || r.Body == NoBody {
-		return 0
-	}
-	if r.ContentLength != 0 {
-		return r.ContentLength
-	}
-	return -1
-}
-
-// requestMethodUsuallyLacksBody reports whether the given request
-// method is one that typically does not involve a request body.
-// This is used by the Transport (via
-// transferWriter.shouldSendChunkedRequestBody) to determine whether
-// we try to test-read a byte from a non-nil Request.Body when
-// Request.outgoingLength() returns -1. See the comments in
-// shouldSendChunkedRequestBody.
-func requestMethodUsuallyLacksBody(method string) bool {
-	switch method {
-	case "GET", "HEAD", "DELETE", "OPTIONS", "PROPFIND", "SEARCH":
-		return true
-	}
-	return false
-}
-
-// requiresHTTP1 reports whether this request requires being sent on
-// an HTTP/1 connection.
-func (r *Request) requiresHTTP1() bool {
-	return hasToken(r.Header.Get("Connection"), "upgrade") &&
-		ascii.EqualFold(r.Header.Get("Upgrade"), "websocket")
-}
diff --git a/contrib/go/_std_1.18/src/net/http/response.go b/contrib/go/_std_1.18/src/net/http/response.go
deleted file mode 100644
index 297394eabe..0000000000
--- a/contrib/go/_std_1.18/src/net/http/response.go
+++ /dev/null
@@ -1,369 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// HTTP Response reading and parsing.
-
-package http
-
-import (
-	"bufio"
-	"bytes"
-	"crypto/tls"
-	"errors"
-	"fmt"
-	"io"
-	"net/textproto"
-	"net/url"
-	"strconv"
-	"strings"
-
-	"golang.org/x/net/http/httpguts"
-)
-
-var respExcludeHeader = map[string]bool{
-	"Content-Length":    true,
-	"Transfer-Encoding": true,
-	"Trailer":           true,
-}
-
-// Response represents the response from an HTTP request.
-//
-// The Client and Transport return Responses from servers once
-// the response headers have been received. The response body
-// is streamed on demand as the Body field is read.
-type Response struct {
-	Status     string // e.g. "200 OK"
-	StatusCode int    // e.g. 200
-	Proto      string // e.g. "HTTP/1.0"
-	ProtoMajor int    // e.g. 1
-	ProtoMinor int    // e.g. 0
-
-	// Header maps header keys to values. If the response had multiple
-	// headers with the same key, they may be concatenated, with comma
-	// delimiters.  (RFC 7230, section 3.2.2 requires that multiple headers
-	// be semantically equivalent to a comma-delimited sequence.) When
-	// Header values are duplicated by other fields in this struct (e.g.,
-	// ContentLength, TransferEncoding, Trailer), the field values are
-	// authoritative.
-	//
-	// Keys in the map are canonicalized (see CanonicalHeaderKey).
-	Header Header
-
-	// Body represents the response body.
-	//
-	// The response body is streamed on demand as the Body field
-	// is read. If the network connection fails or the server
-	// terminates the response, Body.Read calls return an error.
-	//
-	// The http Client and Transport guarantee that Body is always
-	// non-nil, even on responses without a body or responses with
-	// a zero-length body. It is the caller's responsibility to
-	// close Body. The default HTTP client's Transport may not
-	// reuse HTTP/1.x "keep-alive" TCP connections if the Body is
-	// not read to completion and closed.
-	//
-	// The Body is automatically dechunked if the server replied
-	// with a "chunked" Transfer-Encoding.
-	//
-	// As of Go 1.12, the Body will also implement io.Writer
-	// on a successful "101 Switching Protocols" response,
-	// as used by WebSockets and HTTP/2's "h2c" mode.
-	Body io.ReadCloser
-
-	// ContentLength records the length of the associated content. The
-	// value -1 indicates that the length is unknown. Unless Request.Method
-	// is "HEAD", values >= 0 indicate that the given number of bytes may
-	// be read from Body.
-	ContentLength int64
-
-	// Contains transfer encodings from outer-most to inner-most. Value is
-	// nil, means that "identity" encoding is used.
-	TransferEncoding []string
-
-	// Close records whether the header directed that the connection be
-	// closed after reading Body. The value is advice for clients: neither
-	// ReadResponse nor Response.Write ever closes a connection.
-	Close bool
-
-	// Uncompressed reports whether the response was sent compressed but
-	// was decompressed by the http package. When true, reading from
-	// Body yields the uncompressed content instead of the compressed
-	// content actually set from the server, ContentLength is set to -1,
-	// and the "Content-Length" and "Content-Encoding" fields are deleted
-	// from the responseHeader. To get the original response from
-	// the server, set Transport.DisableCompression to true.
-	Uncompressed bool
-
-	// Trailer maps trailer keys to values in the same
-	// format as Header.
-	//
-	// The Trailer initially contains only nil values, one for
-	// each key specified in the server's "Trailer" header
-	// value. Those values are not added to Header.
-	//
-	// Trailer must not be accessed concurrently with Read calls
-	// on the Body.
-	//
-	// After Body.Read has returned io.EOF, Trailer will contain
-	// any trailer values sent by the server.
-	Trailer Header
-
-	// Request is the request that was sent to obtain this Response.
-	// Request's Body is nil (having already been consumed).
-	// This is only populated for Client requests.
-	Request *Request
-
-	// TLS contains information about the TLS connection on which the
-	// response was received. It is nil for unencrypted responses.
-	// The pointer is shared between responses and should not be
-	// modified.
-	TLS *tls.ConnectionState
-}
-
-// Cookies parses and returns the cookies set in the Set-Cookie headers.
-func (r *Response) Cookies() []*Cookie {
-	return readSetCookies(r.Header)
-}
-
-// ErrNoLocation is returned by Response's Location method
-// when no Location header is present.
-var ErrNoLocation = errors.New("http: no Location header in response")
-
-// Location returns the URL of the response's "Location" header,
-// if present. Relative redirects are resolved relative to
-// the Response's Request. ErrNoLocation is returned if no
-// Location header is present.
-func (r *Response) Location() (*url.URL, error) {
-	lv := r.Header.Get("Location")
-	if lv == "" {
-		return nil, ErrNoLocation
-	}
-	if r.Request != nil && r.Request.URL != nil {
-		return r.Request.URL.Parse(lv)
-	}
-	return url.Parse(lv)
-}
-
-// ReadResponse reads and returns an HTTP response from r.
-// The req parameter optionally specifies the Request that corresponds
-// to this Response. If nil, a GET request is assumed.
-// Clients must call resp.Body.Close when finished reading resp.Body.
-// After that call, clients can inspect resp.Trailer to find key/value
-// pairs included in the response trailer.
-func ReadResponse(r *bufio.Reader, req *Request) (*Response, error) {
-	tp := textproto.NewReader(r)
-	resp := &Response{
-		Request: req,
-	}
-
-	// Parse the first line of the response.
-	line, err := tp.ReadLine()
-	if err != nil {
-		if err == io.EOF {
-			err = io.ErrUnexpectedEOF
-		}
-		return nil, err
-	}
-	proto, status, ok := strings.Cut(line, " ")
-	if !ok {
-		return nil, badStringError("malformed HTTP response", line)
-	}
-	resp.Proto = proto
-	resp.Status = strings.TrimLeft(status, " ")
-
-	statusCode, _, _ := strings.Cut(resp.Status, " ")
-	if len(statusCode) != 3 {
-		return nil, badStringError("malformed HTTP status code", statusCode)
-	}
-	resp.StatusCode, err = strconv.Atoi(statusCode)
-	if err != nil || resp.StatusCode < 0 {
-		return nil, badStringError("malformed HTTP status code", statusCode)
-	}
-	if resp.ProtoMajor, resp.ProtoMinor, ok = ParseHTTPVersion(resp.Proto); !ok {
-		return nil, badStringError("malformed HTTP version", resp.Proto)
-	}
-
-	// Parse the response headers.
-	mimeHeader, err := tp.ReadMIMEHeader()
-	if err != nil {
-		if err == io.EOF {
-			err = io.ErrUnexpectedEOF
-		}
-		return nil, err
-	}
-	resp.Header = Header(mimeHeader)
-
-	fixPragmaCacheControl(resp.Header)
-
-	err = readTransfer(resp, r)
-	if err != nil {
-		return nil, err
-	}
-
-	return resp, nil
-}
-
-// RFC 7234, section 5.4: Should treat
-//	Pragma: no-cache
-// like
-//	Cache-Control: no-cache
-func fixPragmaCacheControl(header Header) {
-	if hp, ok := header["Pragma"]; ok && len(hp) > 0 && hp[0] == "no-cache" {
-		if _, presentcc := header["Cache-Control"]; !presentcc {
-			header["Cache-Control"] = []string{"no-cache"}
-		}
-	}
-}
-
-// ProtoAtLeast reports whether the HTTP protocol used
-// in the response is at least major.minor.
-func (r *Response) ProtoAtLeast(major, minor int) bool {
-	return r.ProtoMajor > major ||
-		r.ProtoMajor == major && r.ProtoMinor >= minor
-}
-
-// Write writes r to w in the HTTP/1.x server response format,
-// including the status line, headers, body, and optional trailer.
-//
-// This method consults the following fields of the response r:
-//
-//  StatusCode
-//  ProtoMajor
-//  ProtoMinor
-//  Request.Method
-//  TransferEncoding
-//  Trailer
-//  Body
-//  ContentLength
-//  Header, values for non-canonical keys will have unpredictable behavior
-//
-// The Response Body is closed after it is sent.
-func (r *Response) Write(w io.Writer) error {
-	// Status line
-	text := r.Status
-	if text == "" {
-		var ok bool
-		text, ok = statusText[r.StatusCode]
-		if !ok {
-			text = "status code " + strconv.Itoa(r.StatusCode)
-		}
-	} else {
-		// Just to reduce stutter, if user set r.Status to "200 OK" and StatusCode to 200.
-		// Not important.
-		text = strings.TrimPrefix(text, strconv.Itoa(r.StatusCode)+" ")
-	}
-
-	if _, err := fmt.Fprintf(w, "HTTP/%d.%d %03d %s\r\n", r.ProtoMajor, r.ProtoMinor, r.StatusCode, text); err != nil {
-		return err
-	}
-
-	// Clone it, so we can modify r1 as needed.
-	r1 := new(Response)
-	*r1 = *r
-	if r1.ContentLength == 0 && r1.Body != nil {
-		// Is it actually 0 length? Or just unknown?
-		var buf [1]byte
-		n, err := r1.Body.Read(buf[:])
-		if err != nil && err != io.EOF {
-			return err
-		}
-		if n == 0 {
-			// Reset it to a known zero reader, in case underlying one
-			// is unhappy being read repeatedly.
-			r1.Body = NoBody
-		} else {
-			r1.ContentLength = -1
-			r1.Body = struct {
-				io.Reader
-				io.Closer
-			}{
-				io.MultiReader(bytes.NewReader(buf[:1]), r.Body),
-				r.Body,
-			}
-		}
-	}
-	// If we're sending a non-chunked HTTP/1.1 response without a
-	// content-length, the only way to do that is the old HTTP/1.0
-	// way, by noting the EOF with a connection close, so we need
-	// to set Close.
-	if r1.ContentLength == -1 && !r1.Close && r1.ProtoAtLeast(1, 1) && !chunked(r1.TransferEncoding) && !r1.Uncompressed {
-		r1.Close = true
-	}
-
-	// Process Body,ContentLength,Close,Trailer
-	tw, err := newTransferWriter(r1)
-	if err != nil {
-		return err
-	}
-	err = tw.writeHeader(w, nil)
-	if err != nil {
-		return err
-	}
-
-	// Rest of header
-	err = r.Header.WriteSubset(w, respExcludeHeader)
-	if err != nil {
-		return err
-	}
-
-	// contentLengthAlreadySent may have been already sent for
-	// POST/PUT requests, even if zero length. See Issue 8180.
-	contentLengthAlreadySent := tw.shouldSendContentLength()
-	if r1.ContentLength == 0 && !chunked(r1.TransferEncoding) && !contentLengthAlreadySent && bodyAllowedForStatus(r.StatusCode) {
-		if _, err := io.WriteString(w, "Content-Length: 0\r\n"); err != nil {
-			return err
-		}
-	}
-
-	// End-of-header
-	if _, err := io.WriteString(w, "\r\n"); err != nil {
-		return err
-	}
-
-	// Write body and trailer
-	err = tw.writeBody(w)
-	if err != nil {
-		return err
-	}
-
-	// Success
-	return nil
-}
-
-func (r *Response) closeBody() {
-	if r.Body != nil {
-		r.Body.Close()
-	}
-}
-
-// bodyIsWritable reports whether the Body supports writing. The
-// Transport returns Writable bodies for 101 Switching Protocols
-// responses.
-// The Transport uses this method to determine whether a persistent
-// connection is done being managed from its perspective. Once we
-// return a writable response body to a user, the net/http package is
-// done managing that connection.
-func (r *Response) bodyIsWritable() bool {
-	_, ok := r.Body.(io.Writer)
-	return ok
-}
-
-// isProtocolSwitch reports whether the response code and header
-// indicate a successful protocol upgrade response.
-func (r *Response) isProtocolSwitch() bool {
-	return isProtocolSwitchResponse(r.StatusCode, r.Header)
-}
-
-// isProtocolSwitchResponse reports whether the response code and
-// response header indicate a successful protocol upgrade response.
-func isProtocolSwitchResponse(code int, h Header) bool {
-	return code == StatusSwitchingProtocols && isProtocolSwitchHeader(h)
-}
-
-// isProtocolSwitchHeader reports whether the request or response header
-// is for a protocol switch.
-func isProtocolSwitchHeader(h Header) bool {
-	return h.Get("Upgrade") != "" &&
-		httpguts.HeaderValuesContainsToken(h["Connection"], "Upgrade")
-}
diff --git a/contrib/go/_std_1.18/src/net/http/server.go b/contrib/go/_std_1.18/src/net/http/server.go
deleted file mode 100644
index ffb742ba4a..0000000000
--- a/contrib/go/_std_1.18/src/net/http/server.go
+++ /dev/null
@@ -1,3622 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// HTTP server. See RFC 7230 through 7235.
-
-package http
-
-import (
-	"bufio"
-	"bytes"
-	"context"
-	"crypto/tls"
-	"errors"
-	"fmt"
-	"internal/godebug"
-	"io"
-	"log"
-	"math/rand"
-	"net"
-	"net/textproto"
-	"net/url"
-	urlpkg "net/url"
-	"path"
-	"runtime"
-	"sort"
-	"strconv"
-	"strings"
-	"sync"
-	"sync/atomic"
-	"time"
-
-	"golang.org/x/net/http/httpguts"
-)
-
-// Errors used by the HTTP server.
-var (
-	// ErrBodyNotAllowed is returned by ResponseWriter.Write calls
-	// when the HTTP method or response code does not permit a
-	// body.
-	ErrBodyNotAllowed = errors.New("http: request method or response status code does not allow body")
-
-	// ErrHijacked is returned by ResponseWriter.Write calls when
-	// the underlying connection has been hijacked using the
-	// Hijacker interface. A zero-byte write on a hijacked
-	// connection will return ErrHijacked without any other side
-	// effects.
-	ErrHijacked = errors.New("http: connection has been hijacked")
-
-	// ErrContentLength is returned by ResponseWriter.Write calls
-	// when a Handler set a Content-Length response header with a
-	// declared size and then attempted to write more bytes than
-	// declared.
-	ErrContentLength = errors.New("http: wrote more than the declared Content-Length")
-
-	// Deprecated: ErrWriteAfterFlush is no longer returned by
-	// anything in the net/http package. Callers should not
-	// compare errors against this variable.
-	ErrWriteAfterFlush = errors.New("unused")
-)
-
-// A Handler responds to an HTTP request.
-//
-// ServeHTTP should write reply headers and data to the ResponseWriter
-// and then return. Returning signals that the request is finished; it
-// is not valid to use the ResponseWriter or read from the
-// Request.Body after or concurrently with the completion of the
-// ServeHTTP call.
-//
-// Depending on the HTTP client software, HTTP protocol version, and
-// any intermediaries between the client and the Go server, it may not
-// be possible to read from the Request.Body after writing to the
-// ResponseWriter. Cautious handlers should read the Request.Body
-// first, and then reply.
-//
-// Except for reading the body, handlers should not modify the
-// provided Request.
-//
-// If ServeHTTP panics, the server (the caller of ServeHTTP) assumes
-// that the effect of the panic was isolated to the active request.
-// It recovers the panic, logs a stack trace to the server error log,
-// and either closes the network connection or sends an HTTP/2
-// RST_STREAM, depending on the HTTP protocol. To abort a handler so
-// the client sees an interrupted response but the server doesn't log
-// an error, panic with the value ErrAbortHandler.
-type Handler interface {
-	ServeHTTP(ResponseWriter, *Request)
-}
-
-// A ResponseWriter interface is used by an HTTP handler to
-// construct an HTTP response.
-//
-// A ResponseWriter may not be used after the Handler.ServeHTTP method
-// has returned.
-type ResponseWriter interface {
-	// Header returns the header map that will be sent by
-	// WriteHeader. The Header map also is the mechanism with which
-	// Handlers can set HTTP trailers.
-	//
-	// Changing the header map after a call to WriteHeader (or
-	// Write) has no effect unless the modified headers are
-	// trailers.
-	//
-	// There are two ways to set Trailers. The preferred way is to
-	// predeclare in the headers which trailers you will later
-	// send by setting the "Trailer" header to the names of the
-	// trailer keys which will come later. In this case, those
-	// keys of the Header map are treated as if they were
-	// trailers. See the example. The second way, for trailer
-	// keys not known to the Handler until after the first Write,
-	// is to prefix the Header map keys with the TrailerPrefix
-	// constant value. See TrailerPrefix.
-	//
-	// To suppress automatic response headers (such as "Date"), set
-	// their value to nil.
-	Header() Header
-
-	// Write writes the data to the connection as part of an HTTP reply.
-	//
-	// If WriteHeader has not yet been called, Write calls
-	// WriteHeader(http.StatusOK) before writing the data. If the Header
-	// does not contain a Content-Type line, Write adds a Content-Type set
-	// to the result of passing the initial 512 bytes of written data to
-	// DetectContentType. Additionally, if the total size of all written
-	// data is under a few KB and there are no Flush calls, the
-	// Content-Length header is added automatically.
-	//
-	// Depending on the HTTP protocol version and the client, calling
-	// Write or WriteHeader may prevent future reads on the
-	// Request.Body. For HTTP/1.x requests, handlers should read any
-	// needed request body data before writing the response. Once the
-	// headers have been flushed (due to either an explicit Flusher.Flush
-	// call or writing enough data to trigger a flush), the request body
-	// may be unavailable. For HTTP/2 requests, the Go HTTP server permits
-	// handlers to continue to read the request body while concurrently
-	// writing the response. However, such behavior may not be supported
-	// by all HTTP/2 clients. Handlers should read before writing if
-	// possible to maximize compatibility.
-	Write([]byte) (int, error)
-
-	// WriteHeader sends an HTTP response header with the provided
-	// status code.
-	//
-	// If WriteHeader is not called explicitly, the first call to Write
-	// will trigger an implicit WriteHeader(http.StatusOK).
-	// Thus explicit calls to WriteHeader are mainly used to
-	// send error codes.
-	//
-	// The provided code must be a valid HTTP 1xx-5xx status code.
-	// Only one header may be written. Go does not currently
-	// support sending user-defined 1xx informational headers,
-	// with the exception of 100-continue response header that the
-	// Server sends automatically when the Request.Body is read.
-	WriteHeader(statusCode int)
-}
-
-// The Flusher interface is implemented by ResponseWriters that allow
-// an HTTP handler to flush buffered data to the client.
-//
-// The default HTTP/1.x and HTTP/2 ResponseWriter implementations
-// support Flusher, but ResponseWriter wrappers may not. Handlers
-// should always test for this ability at runtime.
-//
-// Note that even for ResponseWriters that support Flush,
-// if the client is connected through an HTTP proxy,
-// the buffered data may not reach the client until the response
-// completes.
-type Flusher interface {
-	// Flush sends any buffered data to the client.
-	Flush()
-}
-
-// The Hijacker interface is implemented by ResponseWriters that allow
-// an HTTP handler to take over the connection.
-//
-// The default ResponseWriter for HTTP/1.x connections supports
-// Hijacker, but HTTP/2 connections intentionally do not.
-// ResponseWriter wrappers may also not support Hijacker. Handlers
-// should always test for this ability at runtime.
-type Hijacker interface {
-	// Hijack lets the caller take over the connection.
-	// After a call to Hijack the HTTP server library
-	// will not do anything else with the connection.
-	//
-	// It becomes the caller's responsibility to manage
-	// and close the connection.
-	//
-	// The returned net.Conn may have read or write deadlines
-	// already set, depending on the configuration of the
-	// Server. It is the caller's responsibility to set
-	// or clear those deadlines as needed.
-	//
-	// The returned bufio.Reader may contain unprocessed buffered
-	// data from the client.
-	//
-	// After a call to Hijack, the original Request.Body must not
-	// be used. The original Request's Context remains valid and
-	// is not canceled until the Request's ServeHTTP method
-	// returns.
-	Hijack() (net.Conn, *bufio.ReadWriter, error)
-}
-
-// The CloseNotifier interface is implemented by ResponseWriters which
-// allow detecting when the underlying connection has gone away.
-//
-// This mechanism can be used to cancel long operations on the server
-// if the client has disconnected before the response is ready.
-//
-// Deprecated: the CloseNotifier interface predates Go's context package.
-// New code should use Request.Context instead.
-type CloseNotifier interface {
-	// CloseNotify returns a channel that receives at most a
-	// single value (true) when the client connection has gone
-	// away.
-	//
-	// CloseNotify may wait to notify until Request.Body has been
-	// fully read.
-	//
-	// After the Handler has returned, there is no guarantee
-	// that the channel receives a value.
-	//
-	// If the protocol is HTTP/1.1 and CloseNotify is called while
-	// processing an idempotent request (such a GET) while
-	// HTTP/1.1 pipelining is in use, the arrival of a subsequent
-	// pipelined request may cause a value to be sent on the
-	// returned channel. In practice HTTP/1.1 pipelining is not
-	// enabled in browsers and not seen often in the wild. If this
-	// is a problem, use HTTP/2 or only use CloseNotify on methods
-	// such as POST.
-	CloseNotify() <-chan bool
-}
-
-var (
-	// ServerContextKey is a context key. It can be used in HTTP
-	// handlers with Context.Value to access the server that
-	// started the handler. The associated value will be of
-	// type *Server.
-	ServerContextKey = &contextKey{"http-server"}
-
-	// LocalAddrContextKey is a context key. It can be used in
-	// HTTP handlers with Context.Value to access the local
-	// address the connection arrived on.
-	// The associated value will be of type net.Addr.
-	LocalAddrContextKey = &contextKey{"local-addr"}
-)
-
-// A conn represents the server side of an HTTP connection.
-type conn struct {
-	// server is the server on which the connection arrived.
-	// Immutable; never nil.
-	server *Server
-
-	// cancelCtx cancels the connection-level context.
-	cancelCtx context.CancelFunc
-
-	// rwc is the underlying network connection.
-	// This is never wrapped by other types and is the value given out
-	// to CloseNotifier callers. It is usually of type *net.TCPConn or
-	// *tls.Conn.
-	rwc net.Conn
-
-	// remoteAddr is rwc.RemoteAddr().String(). It is not populated synchronously
-	// inside the Listener's Accept goroutine, as some implementations block.
-	// It is populated immediately inside the (*conn).serve goroutine.
-	// This is the value of a Handler's (*Request).RemoteAddr.
-	remoteAddr string
-
-	// tlsState is the TLS connection state when using TLS.
-	// nil means not TLS.
-	tlsState *tls.ConnectionState
-
-	// werr is set to the first write error to rwc.
-	// It is set via checkConnErrorWriter{w}, where bufw writes.
-	werr error
-
-	// r is bufr's read source. It's a wrapper around rwc that provides
-	// io.LimitedReader-style limiting (while reading request headers)
-	// and functionality to support CloseNotifier. See *connReader docs.
-	r *connReader
-
-	// bufr reads from r.
-	bufr *bufio.Reader
-
-	// bufw writes to checkConnErrorWriter{c}, which populates werr on error.
-	bufw *bufio.Writer
-
-	// lastMethod is the method of the most recent request
-	// on this connection, if any.
-	lastMethod string
-
-	curReq atomic.Value // of *response (which has a Request in it)
-
-	curState struct{ atomic uint64 } // packed (unixtime<<8|uint8(ConnState))
-
-	// mu guards hijackedv
-	mu sync.Mutex
-
-	// hijackedv is whether this connection has been hijacked
-	// by a Handler with the Hijacker interface.
-	// It is guarded by mu.
-	hijackedv bool
-}
-
-func (c *conn) hijacked() bool {
-	c.mu.Lock()
-	defer c.mu.Unlock()
-	return c.hijackedv
-}
-
-// c.mu must be held.
-func (c *conn) hijackLocked() (rwc net.Conn, buf *bufio.ReadWriter, err error) {
-	if c.hijackedv {
-		return nil, nil, ErrHijacked
-	}
-	c.r.abortPendingRead()
-
-	c.hijackedv = true
-	rwc = c.rwc
-	rwc.SetDeadline(time.Time{})
-
-	buf = bufio.NewReadWriter(c.bufr, bufio.NewWriter(rwc))
-	if c.r.hasByte {
-		if _, err := c.bufr.Peek(c.bufr.Buffered() + 1); err != nil {
-			return nil, nil, fmt.Errorf("unexpected Peek failure reading buffered byte: %v", err)
-		}
-	}
-	c.setState(rwc, StateHijacked, runHooks)
-	return
-}
-
-// This should be >= 512 bytes for DetectContentType,
-// but otherwise it's somewhat arbitrary.
-const bufferBeforeChunkingSize = 2048
-
-// chunkWriter writes to a response's conn buffer, and is the writer
-// wrapped by the response.w buffered writer.
-//
-// chunkWriter also is responsible for finalizing the Header, including
-// conditionally setting the Content-Type and setting a Content-Length
-// in cases where the handler's final output is smaller than the buffer
-// size. It also conditionally adds chunk headers, when in chunking mode.
-//
-// See the comment above (*response).Write for the entire write flow.
-type chunkWriter struct {
-	res *response
-
-	// header is either nil or a deep clone of res.handlerHeader
-	// at the time of res.writeHeader, if res.writeHeader is
-	// called and extra buffering is being done to calculate
-	// Content-Type and/or Content-Length.
-	header Header
-
-	// wroteHeader tells whether the header's been written to "the
-	// wire" (or rather: w.conn.buf). this is unlike
-	// (*response).wroteHeader, which tells only whether it was
-	// logically written.
-	wroteHeader bool
-
-	// set by the writeHeader method:
-	chunking bool // using chunked transfer encoding for reply body
-}
-
-var (
-	crlf       = []byte("\r\n")
-	colonSpace = []byte(": ")
-)
-
-func (cw *chunkWriter) Write(p []byte) (n int, err error) {
-	if !cw.wroteHeader {
-		cw.writeHeader(p)
-	}
-	if cw.res.req.Method == "HEAD" {
-		// Eat writes.
-		return len(p), nil
-	}
-	if cw.chunking {
-		_, err = fmt.Fprintf(cw.res.conn.bufw, "%x\r\n", len(p))
-		if err != nil {
-			cw.res.conn.rwc.Close()
-			return
-		}
-	}
-	n, err = cw.res.conn.bufw.Write(p)
-	if cw.chunking && err == nil {
-		_, err = cw.res.conn.bufw.Write(crlf)
-	}
-	if err != nil {
-		cw.res.conn.rwc.Close()
-	}
-	return
-}
-
-func (cw *chunkWriter) flush() {
-	if !cw.wroteHeader {
-		cw.writeHeader(nil)
-	}
-	cw.res.conn.bufw.Flush()
-}
-
-func (cw *chunkWriter) close() {
-	if !cw.wroteHeader {
-		cw.writeHeader(nil)
-	}
-	if cw.chunking {
-		bw := cw.res.conn.bufw // conn's bufio writer
-		// zero chunk to mark EOF
-		bw.WriteString("0\r\n")
-		if trailers := cw.res.finalTrailers(); trailers != nil {
-			trailers.Write(bw) // the writer handles noting errors
-		}
-		// final blank line after the trailers (whether
-		// present or not)
-		bw.WriteString("\r\n")
-	}
-}
-
-// A response represents the server side of an HTTP response.
-type response struct {
-	conn             *conn
-	req              *Request // request for this response
-	reqBody          io.ReadCloser
-	cancelCtx        context.CancelFunc // when ServeHTTP exits
-	wroteHeader      bool               // reply header has been (logically) written
-	wroteContinue    bool               // 100 Continue response was written
-	wants10KeepAlive bool               // HTTP/1.0 w/ Connection "keep-alive"
-	wantsClose       bool               // HTTP request has Connection "close"
-
-	// canWriteContinue is a boolean value accessed as an atomic int32
-	// that says whether or not a 100 Continue header can be written
-	// to the connection.
-	// writeContinueMu must be held while writing the header.
-	// These two fields together synchronize the body reader
-	// (the expectContinueReader, which wants to write 100 Continue)
-	// against the main writer.
-	canWriteContinue atomicBool
-	writeContinueMu  sync.Mutex
-
-	w  *bufio.Writer // buffers output in chunks to chunkWriter
-	cw chunkWriter
-
-	// handlerHeader is the Header that Handlers get access to,
-	// which may be retained and mutated even after WriteHeader.
-	// handlerHeader is copied into cw.header at WriteHeader
-	// time, and privately mutated thereafter.
-	handlerHeader Header
-	calledHeader  bool // handler accessed handlerHeader via Header
-
-	written       int64 // number of bytes written in body
-	contentLength int64 // explicitly-declared Content-Length; or -1
-	status        int   // status code passed to WriteHeader
-
-	// close connection after this reply.  set on request and
-	// updated after response from handler if there's a
-	// "Connection: keep-alive" response header and a
-	// Content-Length.
-	closeAfterReply bool
-
-	// requestBodyLimitHit is set by requestTooLarge when
-	// maxBytesReader hits its max size. It is checked in
-	// WriteHeader, to make sure we don't consume the
-	// remaining request body to try to advance to the next HTTP
-	// request. Instead, when this is set, we stop reading
-	// subsequent requests on this connection and stop reading
-	// input from it.
-	requestBodyLimitHit bool
-
-	// trailers are the headers to be sent after the handler
-	// finishes writing the body. This field is initialized from
-	// the Trailer response header when the response header is
-	// written.
-	trailers []string
-
-	handlerDone atomicBool // set true when the handler exits
-
-	// Buffers for Date, Content-Length, and status code
-	dateBuf   [len(TimeFormat)]byte
-	clenBuf   [10]byte
-	statusBuf [3]byte
-
-	// closeNotifyCh is the channel returned by CloseNotify.
-	// TODO(bradfitz): this is currently (for Go 1.8) always
-	// non-nil. Make this lazily-created again as it used to be?
-	closeNotifyCh  chan bool
-	didCloseNotify int32 // atomic (only 0->1 winner should send)
-}
-
-// TrailerPrefix is a magic prefix for ResponseWriter.Header map keys
-// that, if present, signals that the map entry is actually for
-// the response trailers, and not the response headers. The prefix
-// is stripped after the ServeHTTP call finishes and the values are
-// sent in the trailers.
-//
-// This mechanism is intended only for trailers that are not known
-// prior to the headers being written. If the set of trailers is fixed
-// or known before the header is written, the normal Go trailers mechanism
-// is preferred:
-//    https://pkg.go.dev/net/http#ResponseWriter
-//    https://pkg.go.dev/net/http#example-ResponseWriter-Trailers
-const TrailerPrefix = "Trailer:"
-
-// finalTrailers is called after the Handler exits and returns a non-nil
-// value if the Handler set any trailers.
-func (w *response) finalTrailers() Header {
-	var t Header
-	for k, vv := range w.handlerHeader {
-		if strings.HasPrefix(k, TrailerPrefix) {
-			if t == nil {
-				t = make(Header)
-			}
-			t[strings.TrimPrefix(k, TrailerPrefix)] = vv
-		}
-	}
-	for _, k := range w.trailers {
-		if t == nil {
-			t = make(Header)
-		}
-		for _, v := range w.handlerHeader[k] {
-			t.Add(k, v)
-		}
-	}
-	return t
-}
-
-type atomicBool int32
-
-func (b *atomicBool) isSet() bool { return atomic.LoadInt32((*int32)(b)) != 0 }
-func (b *atomicBool) setTrue()    { atomic.StoreInt32((*int32)(b), 1) }
-func (b *atomicBool) setFalse()   { atomic.StoreInt32((*int32)(b), 0) }
-
-// declareTrailer is called for each Trailer header when the
-// response header is written. It notes that a header will need to be
-// written in the trailers at the end of the response.
-func (w *response) declareTrailer(k string) {
-	k = CanonicalHeaderKey(k)
-	if !httpguts.ValidTrailerHeader(k) {
-		// Forbidden by RFC 7230, section 4.1.2
-		return
-	}
-	w.trailers = append(w.trailers, k)
-}
-
-// requestTooLarge is called by maxBytesReader when too much input has
-// been read from the client.
-func (w *response) requestTooLarge() {
-	w.closeAfterReply = true
-	w.requestBodyLimitHit = true
-	if !w.wroteHeader {
-		w.Header().Set("Connection", "close")
-	}
-}
-
-// needsSniff reports whether a Content-Type still needs to be sniffed.
-func (w *response) needsSniff() bool {
-	_, haveType := w.handlerHeader["Content-Type"]
-	return !w.cw.wroteHeader && !haveType && w.written < sniffLen
-}
-
-// writerOnly hides an io.Writer value's optional ReadFrom method
-// from io.Copy.
-type writerOnly struct {
-	io.Writer
-}
-
-// ReadFrom is here to optimize copying from an *os.File regular file
-// to a *net.TCPConn with sendfile, or from a supported src type such
-// as a *net.TCPConn on Linux with splice.
-func (w *response) ReadFrom(src io.Reader) (n int64, err error) {
-	bufp := copyBufPool.Get().(*[]byte)
-	buf := *bufp
-	defer copyBufPool.Put(bufp)
-
-	// Our underlying w.conn.rwc is usually a *TCPConn (with its
-	// own ReadFrom method). If not, just fall back to the normal
-	// copy method.
-	rf, ok := w.conn.rwc.(io.ReaderFrom)
-	if !ok {
-		return io.CopyBuffer(writerOnly{w}, src, buf)
-	}
-
-	// Copy the first sniffLen bytes before switching to ReadFrom.
-	// This ensures we don't start writing the response before the
-	// source is available (see golang.org/issue/5660) and provides
-	// enough bytes to perform Content-Type sniffing when required.
-	if !w.cw.wroteHeader {
-		n0, err := io.CopyBuffer(writerOnly{w}, io.LimitReader(src, sniffLen), buf)
-		n += n0
-		if err != nil || n0 < sniffLen {
-			return n, err
-		}
-	}
-
-	w.w.Flush()  // get rid of any previous writes
-	w.cw.flush() // make sure Header is written; flush data to rwc
-
-	// Now that cw has been flushed, its chunking field is guaranteed initialized.
-	if !w.cw.chunking && w.bodyAllowed() {
-		n0, err := rf.ReadFrom(src)
-		n += n0
-		w.written += n0
-		return n, err
-	}
-
-	n0, err := io.CopyBuffer(writerOnly{w}, src, buf)
-	n += n0
-	return n, err
-}
-
-// debugServerConnections controls whether all server connections are wrapped
-// with a verbose logging wrapper.
-const debugServerConnections = false
-
-// Create new connection from rwc.
-func (srv *Server) newConn(rwc net.Conn) *conn {
-	c := &conn{
-		server: srv,
-		rwc:    rwc,
-	}
-	if debugServerConnections {
-		c.rwc = newLoggingConn("server", c.rwc)
-	}
-	return c
-}
-
-type readResult struct {
-	_   incomparable
-	n   int
-	err error
-	b   byte // byte read, if n == 1
-}
-
-// connReader is the io.Reader wrapper used by *conn. It combines a
-// selectively-activated io.LimitedReader (to bound request header
-// read sizes) with support for selectively keeping an io.Reader.Read
-// call blocked in a background goroutine to wait for activity and
-// trigger a CloseNotifier channel.
-type connReader struct {
-	conn *conn
-
-	mu      sync.Mutex // guards following
-	hasByte bool
-	byteBuf [1]byte
-	cond    *sync.Cond
-	inRead  bool
-	aborted bool  // set true before conn.rwc deadline is set to past
-	remain  int64 // bytes remaining
-}
-
-func (cr *connReader) lock() {
-	cr.mu.Lock()
-	if cr.cond == nil {
-		cr.cond = sync.NewCond(&cr.mu)
-	}
-}
-
-func (cr *connReader) unlock() { cr.mu.Unlock() }
-
-func (cr *connReader) startBackgroundRead() {
-	cr.lock()
-	defer cr.unlock()
-	if cr.inRead {
-		panic("invalid concurrent Body.Read call")
-	}
-	if cr.hasByte {
-		return
-	}
-	cr.inRead = true
-	cr.conn.rwc.SetReadDeadline(time.Time{})
-	go cr.backgroundRead()
-}
-
-func (cr *connReader) backgroundRead() {
-	n, err := cr.conn.rwc.Read(cr.byteBuf[:])
-	cr.lock()
-	if n == 1 {
-		cr.hasByte = true
-		// We were past the end of the previous request's body already
-		// (since we wouldn't be in a background read otherwise), so
-		// this is a pipelined HTTP request. Prior to Go 1.11 we used to
-		// send on the CloseNotify channel and cancel the context here,
-		// but the behavior was documented as only "may", and we only
-		// did that because that's how CloseNotify accidentally behaved
-		// in very early Go releases prior to context support. Once we
-		// added context support, people used a Handler's
-		// Request.Context() and passed it along. Having that context
-		// cancel on pipelined HTTP requests caused problems.
-		// Fortunately, almost nothing uses HTTP/1.x pipelining.
-		// Unfortunately, apt-get does, or sometimes does.
-		// New Go 1.11 behavior: don't fire CloseNotify or cancel
-		// contexts on pipelined requests. Shouldn't affect people, but
-		// fixes cases like Issue 23921. This does mean that a client
-		// closing their TCP connection after sending a pipelined
-		// request won't cancel the context, but we'll catch that on any
-		// write failure (in checkConnErrorWriter.Write).
-		// If the server never writes, yes, there are still contrived
-		// server & client behaviors where this fails to ever cancel the
-		// context, but that's kinda why HTTP/1.x pipelining died
-		// anyway.
-	}
-	if ne, ok := err.(net.Error); ok && cr.aborted && ne.Timeout() {
-		// Ignore this error. It's the expected error from
-		// another goroutine calling abortPendingRead.
-	} else if err != nil {
-		cr.handleReadError(err)
-	}
-	cr.aborted = false
-	cr.inRead = false
-	cr.unlock()
-	cr.cond.Broadcast()
-}
-
-func (cr *connReader) abortPendingRead() {
-	cr.lock()
-	defer cr.unlock()
-	if !cr.inRead {
-		return
-	}
-	cr.aborted = true
-	cr.conn.rwc.SetReadDeadline(aLongTimeAgo)
-	for cr.inRead {
-		cr.cond.Wait()
-	}
-	cr.conn.rwc.SetReadDeadline(time.Time{})
-}
-
-func (cr *connReader) setReadLimit(remain int64) { cr.remain = remain }
-func (cr *connReader) setInfiniteReadLimit()     { cr.remain = maxInt64 }
-func (cr *connReader) hitReadLimit() bool        { return cr.remain <= 0 }
-
-// handleReadError is called whenever a Read from the client returns a
-// non-nil error.
-//
-// The provided non-nil err is almost always io.EOF or a "use of
-// closed network connection". In any case, the error is not
-// particularly interesting, except perhaps for debugging during
-// development. Any error means the connection is dead and we should
-// down its context.
-//
-// It may be called from multiple goroutines.
-func (cr *connReader) handleReadError(_ error) {
-	cr.conn.cancelCtx()
-	cr.closeNotify()
-}
-
-// may be called from multiple goroutines.
-func (cr *connReader) closeNotify() {
-	res, _ := cr.conn.curReq.Load().(*response)
-	if res != nil && atomic.CompareAndSwapInt32(&res.didCloseNotify, 0, 1) {
-		res.closeNotifyCh <- true
-	}
-}
-
-func (cr *connReader) Read(p []byte) (n int, err error) {
-	cr.lock()
-	if cr.inRead {
-		cr.unlock()
-		if cr.conn.hijacked() {
-			panic("invalid Body.Read call. After hijacked, the original Request must not be used")
-		}
-		panic("invalid concurrent Body.Read call")
-	}
-	if cr.hitReadLimit() {
-		cr.unlock()
-		return 0, io.EOF
-	}
-	if len(p) == 0 {
-		cr.unlock()
-		return 0, nil
-	}
-	if int64(len(p)) > cr.remain {
-		p = p[:cr.remain]
-	}
-	if cr.hasByte {
-		p[0] = cr.byteBuf[0]
-		cr.hasByte = false
-		cr.unlock()
-		return 1, nil
-	}
-	cr.inRead = true
-	cr.unlock()
-	n, err = cr.conn.rwc.Read(p)
-
-	cr.lock()
-	cr.inRead = false
-	if err != nil {
-		cr.handleReadError(err)
-	}
-	cr.remain -= int64(n)
-	cr.unlock()
-
-	cr.cond.Broadcast()
-	return n, err
-}
-
-var (
-	bufioReaderPool   sync.Pool
-	bufioWriter2kPool sync.Pool
-	bufioWriter4kPool sync.Pool
-)
-
-var copyBufPool = sync.Pool{
-	New: func() any {
-		b := make([]byte, 32*1024)
-		return &b
-	},
-}
-
-func bufioWriterPool(size int) *sync.Pool {
-	switch size {
-	case 2 << 10:
-		return &bufioWriter2kPool
-	case 4 << 10:
-		return &bufioWriter4kPool
-	}
-	return nil
-}
-
-func newBufioReader(r io.Reader) *bufio.Reader {
-	if v := bufioReaderPool.Get(); v != nil {
-		br := v.(*bufio.Reader)
-		br.Reset(r)
-		return br
-	}
-	// Note: if this reader size is ever changed, update
-	// TestHandlerBodyClose's assumptions.
-	return bufio.NewReader(r)
-}
-
-func putBufioReader(br *bufio.Reader) {
-	br.Reset(nil)
-	bufioReaderPool.Put(br)
-}
-
-func newBufioWriterSize(w io.Writer, size int) *bufio.Writer {
-	pool := bufioWriterPool(size)
-	if pool != nil {
-		if v := pool.Get(); v != nil {
-			bw := v.(*bufio.Writer)
-			bw.Reset(w)
-			return bw
-		}
-	}
-	return bufio.NewWriterSize(w, size)
-}
-
-func putBufioWriter(bw *bufio.Writer) {
-	bw.Reset(nil)
-	if pool := bufioWriterPool(bw.Available()); pool != nil {
-		pool.Put(bw)
-	}
-}
-
-// DefaultMaxHeaderBytes is the maximum permitted size of the headers
-// in an HTTP request.
-// This can be overridden by setting Server.MaxHeaderBytes.
-const DefaultMaxHeaderBytes = 1 << 20 // 1 MB
-
-func (srv *Server) maxHeaderBytes() int {
-	if srv.MaxHeaderBytes > 0 {
-		return srv.MaxHeaderBytes
-	}
-	return DefaultMaxHeaderBytes
-}
-
-func (srv *Server) initialReadLimitSize() int64 {
-	return int64(srv.maxHeaderBytes()) + 4096 // bufio slop
-}
-
-// tlsHandshakeTimeout returns the time limit permitted for the TLS
-// handshake, or zero for unlimited.
-//
-// It returns the minimum of any positive ReadHeaderTimeout,
-// ReadTimeout, or WriteTimeout.
-func (srv *Server) tlsHandshakeTimeout() time.Duration {
-	var ret time.Duration
-	for _, v := range [...]time.Duration{
-		srv.ReadHeaderTimeout,
-		srv.ReadTimeout,
-		srv.WriteTimeout,
-	} {
-		if v <= 0 {
-			continue
-		}
-		if ret == 0 || v < ret {
-			ret = v
-		}
-	}
-	return ret
-}
-
-// wrapper around io.ReadCloser which on first read, sends an
-// HTTP/1.1 100 Continue header
-type expectContinueReader struct {
-	resp       *response
-	readCloser io.ReadCloser
-	closed     atomicBool
-	sawEOF     atomicBool
-}
-
-func (ecr *expectContinueReader) Read(p []byte) (n int, err error) {
-	if ecr.closed.isSet() {
-		return 0, ErrBodyReadAfterClose
-	}
-	w := ecr.resp
-	if !w.wroteContinue && w.canWriteContinue.isSet() && !w.conn.hijacked() {
-		w.wroteContinue = true
-		w.writeContinueMu.Lock()
-		if w.canWriteContinue.isSet() {
-			w.conn.bufw.WriteString("HTTP/1.1 100 Continue\r\n\r\n")
-			w.conn.bufw.Flush()
-			w.canWriteContinue.setFalse()
-		}
-		w.writeContinueMu.Unlock()
-	}
-	n, err = ecr.readCloser.Read(p)
-	if err == io.EOF {
-		ecr.sawEOF.setTrue()
-	}
-	return
-}
-
-func (ecr *expectContinueReader) Close() error {
-	ecr.closed.setTrue()
-	return ecr.readCloser.Close()
-}
-
-// TimeFormat is the time format to use when generating times in HTTP
-// headers. It is like time.RFC1123 but hard-codes GMT as the time
-// zone. The time being formatted must be in UTC for Format to
-// generate the correct format.
-//
-// For parsing this time format, see ParseTime.
-const TimeFormat = "Mon, 02 Jan 2006 15:04:05 GMT"
-
-// appendTime is a non-allocating version of []byte(t.UTC().Format(TimeFormat))
-func appendTime(b []byte, t time.Time) []byte {
-	const days = "SunMonTueWedThuFriSat"
-	const months = "JanFebMarAprMayJunJulAugSepOctNovDec"
-
-	t = t.UTC()
-	yy, mm, dd := t.Date()
-	hh, mn, ss := t.Clock()
-	day := days[3*t.Weekday():]
-	mon := months[3*(mm-1):]
-
-	return append(b,
-		day[0], day[1], day[2], ',', ' ',
-		byte('0'+dd/10), byte('0'+dd%10), ' ',
-		mon[0], mon[1], mon[2], ' ',
-		byte('0'+yy/1000), byte('0'+(yy/100)%10), byte('0'+(yy/10)%10), byte('0'+yy%10), ' ',
-		byte('0'+hh/10), byte('0'+hh%10), ':',
-		byte('0'+mn/10), byte('0'+mn%10), ':',
-		byte('0'+ss/10), byte('0'+ss%10), ' ',
-		'G', 'M', 'T')
-}
-
-var errTooLarge = errors.New("http: request too large")
-
-// Read next request from connection.
-func (c *conn) readRequest(ctx context.Context) (w *response, err error) {
-	if c.hijacked() {
-		return nil, ErrHijacked
-	}
-
-	var (
-		wholeReqDeadline time.Time // or zero if none
-		hdrDeadline      time.Time // or zero if none
-	)
-	t0 := time.Now()
-	if d := c.server.readHeaderTimeout(); d > 0 {
-		hdrDeadline = t0.Add(d)
-	}
-	if d := c.server.ReadTimeout; d > 0 {
-		wholeReqDeadline = t0.Add(d)
-	}
-	c.rwc.SetReadDeadline(hdrDeadline)
-	if d := c.server.WriteTimeout; d > 0 {
-		defer func() {
-			c.rwc.SetWriteDeadline(time.Now().Add(d))
-		}()
-	}
-
-	c.r.setReadLimit(c.server.initialReadLimitSize())
-	if c.lastMethod == "POST" {
-		// RFC 7230 section 3 tolerance for old buggy clients.
-		peek, _ := c.bufr.Peek(4) // ReadRequest will get err below
-		c.bufr.Discard(numLeadingCRorLF(peek))
-	}
-	req, err := readRequest(c.bufr)
-	if err != nil {
-		if c.r.hitReadLimit() {
-			return nil, errTooLarge
-		}
-		return nil, err
-	}
-
-	if !http1ServerSupportsRequest(req) {
-		return nil, statusError{StatusHTTPVersionNotSupported, "unsupported protocol version"}
-	}
-
-	c.lastMethod = req.Method
-	c.r.setInfiniteReadLimit()
-
-	hosts, haveHost := req.Header["Host"]
-	isH2Upgrade := req.isH2Upgrade()
-	if req.ProtoAtLeast(1, 1) && (!haveHost || len(hosts) == 0) && !isH2Upgrade && req.Method != "CONNECT" {
-		return nil, badRequestError("missing required Host header")
-	}
-	if len(hosts) == 1 && !httpguts.ValidHostHeader(hosts[0]) {
-		return nil, badRequestError("malformed Host header")
-	}
-	for k, vv := range req.Header {
-		if !httpguts.ValidHeaderFieldName(k) {
-			return nil, badRequestError("invalid header name")
-		}
-		for _, v := range vv {
-			if !httpguts.ValidHeaderFieldValue(v) {
-				return nil, badRequestError("invalid header value")
-			}
-		}
-	}
-	delete(req.Header, "Host")
-
-	ctx, cancelCtx := context.WithCancel(ctx)
-	req.ctx = ctx
-	req.RemoteAddr = c.remoteAddr
-	req.TLS = c.tlsState
-	if body, ok := req.Body.(*body); ok {
-		body.doEarlyClose = true
-	}
-
-	// Adjust the read deadline if necessary.
-	if !hdrDeadline.Equal(wholeReqDeadline) {
-		c.rwc.SetReadDeadline(wholeReqDeadline)
-	}
-
-	w = &response{
-		conn:          c,
-		cancelCtx:     cancelCtx,
-		req:           req,
-		reqBody:       req.Body,
-		handlerHeader: make(Header),
-		contentLength: -1,
-		closeNotifyCh: make(chan bool, 1),
-
-		// We populate these ahead of time so we're not
-		// reading from req.Header after their Handler starts
-		// and maybe mutates it (Issue 14940)
-		wants10KeepAlive: req.wantsHttp10KeepAlive(),
-		wantsClose:       req.wantsClose(),
-	}
-	if isH2Upgrade {
-		w.closeAfterReply = true
-	}
-	w.cw.res = w
-	w.w = newBufioWriterSize(&w.cw, bufferBeforeChunkingSize)
-	return w, nil
-}
-
-// http1ServerSupportsRequest reports whether Go's HTTP/1.x server
-// supports the given request.
-func http1ServerSupportsRequest(req *Request) bool {
-	if req.ProtoMajor == 1 {
-		return true
-	}
-	// Accept "PRI * HTTP/2.0" upgrade requests, so Handlers can
-	// wire up their own HTTP/2 upgrades.
-	if req.ProtoMajor == 2 && req.ProtoMinor == 0 &&
-		req.Method == "PRI" && req.RequestURI == "*" {
-		return true
-	}
-	// Reject HTTP/0.x, and all other HTTP/2+ requests (which
-	// aren't encoded in ASCII anyway).
-	return false
-}
-
-func (w *response) Header() Header {
-	if w.cw.header == nil && w.wroteHeader && !w.cw.wroteHeader {
-		// Accessing the header between logically writing it
-		// and physically writing it means we need to allocate
-		// a clone to snapshot the logically written state.
-		w.cw.header = w.handlerHeader.Clone()
-	}
-	w.calledHeader = true
-	return w.handlerHeader
-}
-
-// maxPostHandlerReadBytes is the max number of Request.Body bytes not
-// consumed by a handler that the server will read from the client
-// in order to keep a connection alive. If there are more bytes than
-// this then the server to be paranoid instead sends a "Connection:
-// close" response.
-//
-// This number is approximately what a typical machine's TCP buffer
-// size is anyway.  (if we have the bytes on the machine, we might as
-// well read them)
-const maxPostHandlerReadBytes = 256 << 10
-
-func checkWriteHeaderCode(code int) {
-	// Issue 22880: require valid WriteHeader status codes.
-	// For now we only enforce that it's three digits.
-	// In the future we might block things over 599 (600 and above aren't defined
-	// at https://httpwg.org/specs/rfc7231.html#status.codes)
-	// and we might block under 200 (once we have more mature 1xx support).
-	// But for now any three digits.
-	//
-	// We used to send "HTTP/1.1 000 0" on the wire in responses but there's
-	// no equivalent bogus thing we can realistically send in HTTP/2,
-	// so we'll consistently panic instead and help people find their bugs
-	// early. (We can't return an error from WriteHeader even if we wanted to.)
-	if code < 100 || code > 999 {
-		panic(fmt.Sprintf("invalid WriteHeader code %v", code))
-	}
-}
-
-// relevantCaller searches the call stack for the first function outside of net/http.
-// The purpose of this function is to provide more helpful error messages.
-func relevantCaller() runtime.Frame {
-	pc := make([]uintptr, 16)
-	n := runtime.Callers(1, pc)
-	frames := runtime.CallersFrames(pc[:n])
-	var frame runtime.Frame
-	for {
-		frame, more := frames.Next()
-		if !strings.HasPrefix(frame.Function, "net/http.") {
-			return frame
-		}
-		if !more {
-			break
-		}
-	}
-	return frame
-}
-
-func (w *response) WriteHeader(code int) {
-	if w.conn.hijacked() {
-		caller := relevantCaller()
-		w.conn.server.logf("http: response.WriteHeader on hijacked connection from %s (%s:%d)", caller.Function, path.Base(caller.File), caller.Line)
-		return
-	}
-	if w.wroteHeader {
-		caller := relevantCaller()
-		w.conn.server.logf("http: superfluous response.WriteHeader call from %s (%s:%d)", caller.Function, path.Base(caller.File), caller.Line)
-		return
-	}
-	checkWriteHeaderCode(code)
-	w.wroteHeader = true
-	w.status = code
-
-	if w.calledHeader && w.cw.header == nil {
-		w.cw.header = w.handlerHeader.Clone()
-	}
-
-	if cl := w.handlerHeader.get("Content-Length"); cl != "" {
-		v, err := strconv.ParseInt(cl, 10, 64)
-		if err == nil && v >= 0 {
-			w.contentLength = v
-		} else {
-			w.conn.server.logf("http: invalid Content-Length of %q", cl)
-			w.handlerHeader.Del("Content-Length")
-		}
-	}
-}
-
-// extraHeader is the set of headers sometimes added by chunkWriter.writeHeader.
-// This type is used to avoid extra allocations from cloning and/or populating
-// the response Header map and all its 1-element slices.
-type extraHeader struct {
-	contentType      string
-	connection       string
-	transferEncoding string
-	date             []byte // written if not nil
-	contentLength    []byte // written if not nil
-}
-
-// Sorted the same as extraHeader.Write's loop.
-var extraHeaderKeys = [][]byte{
-	[]byte("Content-Type"),
-	[]byte("Connection"),
-	[]byte("Transfer-Encoding"),
-}
-
-var (
-	headerContentLength = []byte("Content-Length: ")
-	headerDate          = []byte("Date: ")
-)
-
-// Write writes the headers described in h to w.
-//
-// This method has a value receiver, despite the somewhat large size
-// of h, because it prevents an allocation. The escape analysis isn't
-// smart enough to realize this function doesn't mutate h.
-func (h extraHeader) Write(w *bufio.Writer) {
-	if h.date != nil {
-		w.Write(headerDate)
-		w.Write(h.date)
-		w.Write(crlf)
-	}
-	if h.contentLength != nil {
-		w.Write(headerContentLength)
-		w.Write(h.contentLength)
-		w.Write(crlf)
-	}
-	for i, v := range []string{h.contentType, h.connection, h.transferEncoding} {
-		if v != "" {
-			w.Write(extraHeaderKeys[i])
-			w.Write(colonSpace)
-			w.WriteString(v)
-			w.Write(crlf)
-		}
-	}
-}
-
-// writeHeader finalizes the header sent to the client and writes it
-// to cw.res.conn.bufw.
-//
-// p is not written by writeHeader, but is the first chunk of the body
-// that will be written. It is sniffed for a Content-Type if none is
-// set explicitly. It's also used to set the Content-Length, if the
-// total body size was small and the handler has already finished
-// running.
-func (cw *chunkWriter) writeHeader(p []byte) {
-	if cw.wroteHeader {
-		return
-	}
-	cw.wroteHeader = true
-
-	w := cw.res
-	keepAlivesEnabled := w.conn.server.doKeepAlives()
-	isHEAD := w.req.Method == "HEAD"
-
-	// header is written out to w.conn.buf below. Depending on the
-	// state of the handler, we either own the map or not. If we
-	// don't own it, the exclude map is created lazily for
-	// WriteSubset to remove headers. The setHeader struct holds
-	// headers we need to add.
-	header := cw.header
-	owned := header != nil
-	if !owned {
-		header = w.handlerHeader
-	}
-	var excludeHeader map[string]bool
-	delHeader := func(key string) {
-		if owned {
-			header.Del(key)
-			return
-		}
-		if _, ok := header[key]; !ok {
-			return
-		}
-		if excludeHeader == nil {
-			excludeHeader = make(map[string]bool)
-		}
-		excludeHeader[key] = true
-	}
-	var setHeader extraHeader
-
-	// Don't write out the fake "Trailer:foo" keys. See TrailerPrefix.
-	trailers := false
-	for k := range cw.header {
-		if strings.HasPrefix(k, TrailerPrefix) {
-			if excludeHeader == nil {
-				excludeHeader = make(map[string]bool)
-			}
-			excludeHeader[k] = true
-			trailers = true
-		}
-	}
-	for _, v := range cw.header["Trailer"] {
-		trailers = true
-		foreachHeaderElement(v, cw.res.declareTrailer)
-	}
-
-	te := header.get("Transfer-Encoding")
-	hasTE := te != ""
-
-	// If the handler is done but never sent a Content-Length
-	// response header and this is our first (and last) write, set
-	// it, even to zero. This helps HTTP/1.0 clients keep their
-	// "keep-alive" connections alive.
-	// Exceptions: 304/204/1xx responses never get Content-Length, and if
-	// it was a HEAD request, we don't know the difference between
-	// 0 actual bytes and 0 bytes because the handler noticed it
-	// was a HEAD request and chose not to write anything. So for
-	// HEAD, the handler should either write the Content-Length or
-	// write non-zero bytes. If it's actually 0 bytes and the
-	// handler never looked at the Request.Method, we just don't
-	// send a Content-Length header.
-	// Further, we don't send an automatic Content-Length if they
-	// set a Transfer-Encoding, because they're generally incompatible.
-	if w.handlerDone.isSet() && !trailers && !hasTE && bodyAllowedForStatus(w.status) && header.get("Content-Length") == "" && (!isHEAD || len(p) > 0) {
-		w.contentLength = int64(len(p))
-		setHeader.contentLength = strconv.AppendInt(cw.res.clenBuf[:0], int64(len(p)), 10)
-	}
-
-	// If this was an HTTP/1.0 request with keep-alive and we sent a
-	// Content-Length back, we can make this a keep-alive response ...
-	if w.wants10KeepAlive && keepAlivesEnabled {
-		sentLength := header.get("Content-Length") != ""
-		if sentLength && header.get("Connection") == "keep-alive" {
-			w.closeAfterReply = false
-		}
-	}
-
-	// Check for an explicit (and valid) Content-Length header.
-	hasCL := w.contentLength != -1
-
-	if w.wants10KeepAlive && (isHEAD || hasCL || !bodyAllowedForStatus(w.status)) {
-		_, connectionHeaderSet := header["Connection"]
-		if !connectionHeaderSet {
-			setHeader.connection = "keep-alive"
-		}
-	} else if !w.req.ProtoAtLeast(1, 1) || w.wantsClose {
-		w.closeAfterReply = true
-	}
-
-	if header.get("Connection") == "close" || !keepAlivesEnabled {
-		w.closeAfterReply = true
-	}
-
-	// If the client wanted a 100-continue but we never sent it to
-	// them (or, more strictly: we never finished reading their
-	// request body), don't reuse this connection because it's now
-	// in an unknown state: we might be sending this response at
-	// the same time the client is now sending its request body
-	// after a timeout.  (Some HTTP clients send Expect:
-	// 100-continue but knowing that some servers don't support
-	// it, the clients set a timer and send the body later anyway)
-	// If we haven't seen EOF, we can't skip over the unread body
-	// because we don't know if the next bytes on the wire will be
-	// the body-following-the-timer or the subsequent request.
-	// See Issue 11549.
-	if ecr, ok := w.req.Body.(*expectContinueReader); ok && !ecr.sawEOF.isSet() {
-		w.closeAfterReply = true
-	}
-
-	// Per RFC 2616, we should consume the request body before
-	// replying, if the handler hasn't already done so. But we
-	// don't want to do an unbounded amount of reading here for
-	// DoS reasons, so we only try up to a threshold.
-	// TODO(bradfitz): where does RFC 2616 say that? See Issue 15527
-	// about HTTP/1.x Handlers concurrently reading and writing, like
-	// HTTP/2 handlers can do. Maybe this code should be relaxed?
-	if w.req.ContentLength != 0 && !w.closeAfterReply {
-		var discard, tooBig bool
-
-		switch bdy := w.req.Body.(type) {
-		case *expectContinueReader:
-			if bdy.resp.wroteContinue {
-				discard = true
-			}
-		case *body:
-			bdy.mu.Lock()
-			switch {
-			case bdy.closed:
-				if !bdy.sawEOF {
-					// Body was closed in handler with non-EOF error.
-					w.closeAfterReply = true
-				}
-			case bdy.unreadDataSizeLocked() >= maxPostHandlerReadBytes:
-				tooBig = true
-			default:
-				discard = true
-			}
-			bdy.mu.Unlock()
-		default:
-			discard = true
-		}
-
-		if discard {
-			_, err := io.CopyN(io.Discard, w.reqBody, maxPostHandlerReadBytes+1)
-			switch err {
-			case nil:
-				// There must be even more data left over.
-				tooBig = true
-			case ErrBodyReadAfterClose:
-				// Body was already consumed and closed.
-			case io.EOF:
-				// The remaining body was just consumed, close it.
-				err = w.reqBody.Close()
-				if err != nil {
-					w.closeAfterReply = true
-				}
-			default:
-				// Some other kind of error occurred, like a read timeout, or
-				// corrupt chunked encoding. In any case, whatever remains
-				// on the wire must not be parsed as another HTTP request.
-				w.closeAfterReply = true
-			}
-		}
-
-		if tooBig {
-			w.requestTooLarge()
-			delHeader("Connection")
-			setHeader.connection = "close"
-		}
-	}
-
-	code := w.status
-	if bodyAllowedForStatus(code) {
-		// If no content type, apply sniffing algorithm to body.
-		_, haveType := header["Content-Type"]
-
-		// If the Content-Encoding was set and is non-blank,
-		// we shouldn't sniff the body. See Issue 31753.
-		ce := header.Get("Content-Encoding")
-		hasCE := len(ce) > 0
-		if !hasCE && !haveType && !hasTE && len(p) > 0 {
-			setHeader.contentType = DetectContentType(p)
-		}
-	} else {
-		for _, k := range suppressedHeaders(code) {
-			delHeader(k)
-		}
-	}
-
-	if !header.has("Date") {
-		setHeader.date = appendTime(cw.res.dateBuf[:0], time.Now())
-	}
-
-	if hasCL && hasTE && te != "identity" {
-		// TODO: return an error if WriteHeader gets a return parameter
-		// For now just ignore the Content-Length.
-		w.conn.server.logf("http: WriteHeader called with both Transfer-Encoding of %q and a Content-Length of %d",
-			te, w.contentLength)
-		delHeader("Content-Length")
-		hasCL = false
-	}
-
-	if w.req.Method == "HEAD" || !bodyAllowedForStatus(code) || code == StatusNoContent {
-		// Response has no body.
-		delHeader("Transfer-Encoding")
-	} else if hasCL {
-		// Content-Length has been provided, so no chunking is to be done.
-		delHeader("Transfer-Encoding")
-	} else if w.req.ProtoAtLeast(1, 1) {
-		// HTTP/1.1 or greater: Transfer-Encoding has been set to identity, and no
-		// content-length has been provided. The connection must be closed after the
-		// reply is written, and no chunking is to be done. This is the setup
-		// recommended in the Server-Sent Events candidate recommendation 11,
-		// section 8.
-		if hasTE && te == "identity" {
-			cw.chunking = false
-			w.closeAfterReply = true
-			delHeader("Transfer-Encoding")
-		} else {
-			// HTTP/1.1 or greater: use chunked transfer encoding
-			// to avoid closing the connection at EOF.
-			cw.chunking = true
-			setHeader.transferEncoding = "chunked"
-			if hasTE && te == "chunked" {
-				// We will send the chunked Transfer-Encoding header later.
-				delHeader("Transfer-Encoding")
-			}
-		}
-	} else {
-		// HTTP version < 1.1: cannot do chunked transfer
-		// encoding and we don't know the Content-Length so
-		// signal EOF by closing connection.
-		w.closeAfterReply = true
-		delHeader("Transfer-Encoding") // in case already set
-	}
-
-	// Cannot use Content-Length with non-identity Transfer-Encoding.
-	if cw.chunking {
-		delHeader("Content-Length")
-	}
-	if !w.req.ProtoAtLeast(1, 0) {
-		return
-	}
-
-	// Only override the Connection header if it is not a successful
-	// protocol switch response and if KeepAlives are not enabled.
-	// See https://golang.org/issue/36381.
-	delConnectionHeader := w.closeAfterReply &&
-		(!keepAlivesEnabled || !hasToken(cw.header.get("Connection"), "close")) &&
-		!isProtocolSwitchResponse(w.status, header)
-	if delConnectionHeader {
-		delHeader("Connection")
-		if w.req.ProtoAtLeast(1, 1) {
-			setHeader.connection = "close"
-		}
-	}
-
-	writeStatusLine(w.conn.bufw, w.req.ProtoAtLeast(1, 1), code, w.statusBuf[:])
-	cw.header.WriteSubset(w.conn.bufw, excludeHeader)
-	setHeader.Write(w.conn.bufw)
-	w.conn.bufw.Write(crlf)
-}
-
-// foreachHeaderElement splits v according to the "#rule" construction
-// in RFC 7230 section 7 and calls fn for each non-empty element.
-func foreachHeaderElement(v string, fn func(string)) {
-	v = textproto.TrimString(v)
-	if v == "" {
-		return
-	}
-	if !strings.Contains(v, ",") {
-		fn(v)
-		return
-	}
-	for _, f := range strings.Split(v, ",") {
-		if f = textproto.TrimString(f); f != "" {
-			fn(f)
-		}
-	}
-}
-
-// writeStatusLine writes an HTTP/1.x Status-Line (RFC 7230 Section 3.1.2)
-// to bw. is11 is whether the HTTP request is HTTP/1.1. false means HTTP/1.0.
-// code is the response status code.
-// scratch is an optional scratch buffer. If it has at least capacity 3, it's used.
-func writeStatusLine(bw *bufio.Writer, is11 bool, code int, scratch []byte) {
-	if is11 {
-		bw.WriteString("HTTP/1.1 ")
-	} else {
-		bw.WriteString("HTTP/1.0 ")
-	}
-	if text, ok := statusText[code]; ok {
-		bw.Write(strconv.AppendInt(scratch[:0], int64(code), 10))
-		bw.WriteByte(' ')
-		bw.WriteString(text)
-		bw.WriteString("\r\n")
-	} else {
-		// don't worry about performance
-		fmt.Fprintf(bw, "%03d status code %d\r\n", code, code)
-	}
-}
-
-// bodyAllowed reports whether a Write is allowed for this response type.
-// It's illegal to call this before the header has been flushed.
-func (w *response) bodyAllowed() bool {
-	if !w.wroteHeader {
-		panic("")
-	}
-	return bodyAllowedForStatus(w.status)
-}
-
-// The Life Of A Write is like this:
-//
-// Handler starts. No header has been sent. The handler can either
-// write a header, or just start writing. Writing before sending a header
-// sends an implicitly empty 200 OK header.
-//
-// If the handler didn't declare a Content-Length up front, we either
-// go into chunking mode or, if the handler finishes running before
-// the chunking buffer size, we compute a Content-Length and send that
-// in the header instead.
-//
-// Likewise, if the handler didn't set a Content-Type, we sniff that
-// from the initial chunk of output.
-//
-// The Writers are wired together like:
-//
-// 1. *response (the ResponseWriter) ->
-// 2. (*response).w, a *bufio.Writer of bufferBeforeChunkingSize bytes ->
-// 3. chunkWriter.Writer (whose writeHeader finalizes Content-Length/Type)
-//    and which writes the chunk headers, if needed ->
-// 4. conn.bufw, a *bufio.Writer of default (4kB) bytes, writing to ->
-// 5. checkConnErrorWriter{c}, which notes any non-nil error on Write
-//    and populates c.werr with it if so, but otherwise writes to ->
-// 6. the rwc, the net.Conn.
-//
-// TODO(bradfitz): short-circuit some of the buffering when the
-// initial header contains both a Content-Type and Content-Length.
-// Also short-circuit in (1) when the header's been sent and not in
-// chunking mode, writing directly to (4) instead, if (2) has no
-// buffered data. More generally, we could short-circuit from (1) to
-// (3) even in chunking mode if the write size from (1) is over some
-// threshold and nothing is in (2).  The answer might be mostly making
-// bufferBeforeChunkingSize smaller and having bufio's fast-paths deal
-// with this instead.
-func (w *response) Write(data []byte) (n int, err error) {
-	return w.write(len(data), data, "")
-}
-
-func (w *response) WriteString(data string) (n int, err error) {
-	return w.write(len(data), nil, data)
-}
-
-// either dataB or dataS is non-zero.
-func (w *response) write(lenData int, dataB []byte, dataS string) (n int, err error) {
-	if w.conn.hijacked() {
-		if lenData > 0 {
-			caller := relevantCaller()
-			w.conn.server.logf("http: response.Write on hijacked connection from %s (%s:%d)", caller.Function, path.Base(caller.File), caller.Line)
-		}
-		return 0, ErrHijacked
-	}
-
-	if w.canWriteContinue.isSet() {
-		// Body reader wants to write 100 Continue but hasn't yet.
-		// Tell it not to. The store must be done while holding the lock
-		// because the lock makes sure that there is not an active write
-		// this very moment.
-		w.writeContinueMu.Lock()
-		w.canWriteContinue.setFalse()
-		w.writeContinueMu.Unlock()
-	}
-
-	if !w.wroteHeader {
-		w.WriteHeader(StatusOK)
-	}
-	if lenData == 0 {
-		return 0, nil
-	}
-	if !w.bodyAllowed() {
-		return 0, ErrBodyNotAllowed
-	}
-
-	w.written += int64(lenData) // ignoring errors, for errorKludge
-	if w.contentLength != -1 && w.written > w.contentLength {
-		return 0, ErrContentLength
-	}
-	if dataB != nil {
-		return w.w.Write(dataB)
-	} else {
-		return w.w.WriteString(dataS)
-	}
-}
-
-func (w *response) finishRequest() {
-	w.handlerDone.setTrue()
-
-	if !w.wroteHeader {
-		w.WriteHeader(StatusOK)
-	}
-
-	w.w.Flush()
-	putBufioWriter(w.w)
-	w.cw.close()
-	w.conn.bufw.Flush()
-
-	w.conn.r.abortPendingRead()
-
-	// Close the body (regardless of w.closeAfterReply) so we can
-	// re-use its bufio.Reader later safely.
-	w.reqBody.Close()
-
-	if w.req.MultipartForm != nil {
-		w.req.MultipartForm.RemoveAll()
-	}
-}
-
-// shouldReuseConnection reports whether the underlying TCP connection can be reused.
-// It must only be called after the handler is done executing.
-func (w *response) shouldReuseConnection() bool {
-	if w.closeAfterReply {
-		// The request or something set while executing the
-		// handler indicated we shouldn't reuse this
-		// connection.
-		return false
-	}
-
-	if w.req.Method != "HEAD" && w.contentLength != -1 && w.bodyAllowed() && w.contentLength != w.written {
-		// Did not write enough. Avoid getting out of sync.
-		return false
-	}
-
-	// There was some error writing to the underlying connection
-	// during the request, so don't re-use this conn.
-	if w.conn.werr != nil {
-		return false
-	}
-
-	if w.closedRequestBodyEarly() {
-		return false
-	}
-
-	return true
-}
-
-func (w *response) closedRequestBodyEarly() bool {
-	body, ok := w.req.Body.(*body)
-	return ok && body.didEarlyClose()
-}
-
-func (w *response) Flush() {
-	if !w.wroteHeader {
-		w.WriteHeader(StatusOK)
-	}
-	w.w.Flush()
-	w.cw.flush()
-}
-
-func (c *conn) finalFlush() {
-	if c.bufr != nil {
-		// Steal the bufio.Reader (~4KB worth of memory) and its associated
-		// reader for a future connection.
-		putBufioReader(c.bufr)
-		c.bufr = nil
-	}
-
-	if c.bufw != nil {
-		c.bufw.Flush()
-		// Steal the bufio.Writer (~4KB worth of memory) and its associated
-		// writer for a future connection.
-		putBufioWriter(c.bufw)
-		c.bufw = nil
-	}
-}
-
-// Close the connection.
-func (c *conn) close() {
-	c.finalFlush()
-	c.rwc.Close()
-}
-
-// rstAvoidanceDelay is the amount of time we sleep after closing the
-// write side of a TCP connection before closing the entire socket.
-// By sleeping, we increase the chances that the client sees our FIN
-// and processes its final data before they process the subsequent RST
-// from closing a connection with known unread data.
-// This RST seems to occur mostly on BSD systems. (And Windows?)
-// This timeout is somewhat arbitrary (~latency around the planet).
-const rstAvoidanceDelay = 500 * time.Millisecond
-
-type closeWriter interface {
-	CloseWrite() error
-}
-
-var _ closeWriter = (*net.TCPConn)(nil)
-
-// closeWrite flushes any outstanding data and sends a FIN packet (if
-// client is connected via TCP), signalling that we're done. We then
-// pause for a bit, hoping the client processes it before any
-// subsequent RST.
-//
-// See https://golang.org/issue/3595
-func (c *conn) closeWriteAndWait() {
-	c.finalFlush()
-	if tcp, ok := c.rwc.(closeWriter); ok {
-		tcp.CloseWrite()
-	}
-	time.Sleep(rstAvoidanceDelay)
-}
-
-// validNextProto reports whether the proto is a valid ALPN protocol name.
-// Everything is valid except the empty string and built-in protocol types,
-// so that those can't be overridden with alternate implementations.
-func validNextProto(proto string) bool {
-	switch proto {
-	case "", "http/1.1", "http/1.0":
-		return false
-	}
-	return true
-}
-
-const (
-	runHooks  = true
-	skipHooks = false
-)
-
-func (c *conn) setState(nc net.Conn, state ConnState, runHook bool) {
-	srv := c.server
-	switch state {
-	case StateNew:
-		srv.trackConn(c, true)
-	case StateHijacked, StateClosed:
-		srv.trackConn(c, false)
-	}
-	if state > 0xff || state < 0 {
-		panic("internal error")
-	}
-	packedState := uint64(time.Now().Unix()<<8) | uint64(state)
-	atomic.StoreUint64(&c.curState.atomic, packedState)
-	if !runHook {
-		return
-	}
-	if hook := srv.ConnState; hook != nil {
-		hook(nc, state)
-	}
-}
-
-func (c *conn) getState() (state ConnState, unixSec int64) {
-	packedState := atomic.LoadUint64(&c.curState.atomic)
-	return ConnState(packedState & 0xff), int64(packedState >> 8)
-}
-
-// badRequestError is a literal string (used by in the server in HTML,
-// unescaped) to tell the user why their request was bad. It should
-// be plain text without user info or other embedded errors.
-func badRequestError(e string) error { return statusError{StatusBadRequest, e} }
-
-// statusError is an error used to respond to a request with an HTTP status.
-// The text should be plain text without user info or other embedded errors.
-type statusError struct {
-	code int
-	text string
-}
-
-func (e statusError) Error() string { return StatusText(e.code) + ": " + e.text }
-
-// ErrAbortHandler is a sentinel panic value to abort a handler.
-// While any panic from ServeHTTP aborts the response to the client,
-// panicking with ErrAbortHandler also suppresses logging of a stack
-// trace to the server's error log.
-var ErrAbortHandler = errors.New("net/http: abort Handler")
-
-// isCommonNetReadError reports whether err is a common error
-// encountered during reading a request off the network when the
-// client has gone away or had its read fail somehow. This is used to
-// determine which logs are interesting enough to log about.
-func isCommonNetReadError(err error) bool {
-	if err == io.EOF {
-		return true
-	}
-	if neterr, ok := err.(net.Error); ok && neterr.Timeout() {
-		return true
-	}
-	if oe, ok := err.(*net.OpError); ok && oe.Op == "read" {
-		return true
-	}
-	return false
-}
-
-// Serve a new connection.
-func (c *conn) serve(ctx context.Context) {
-	c.remoteAddr = c.rwc.RemoteAddr().String()
-	ctx = context.WithValue(ctx, LocalAddrContextKey, c.rwc.LocalAddr())
-	var inFlightResponse *response
-	defer func() {
-		if err := recover(); err != nil && err != ErrAbortHandler {
-			const size = 64 << 10
-			buf := make([]byte, size)
-			buf = buf[:runtime.Stack(buf, false)]
-			c.server.logf("http: panic serving %v: %v\n%s", c.remoteAddr, err, buf)
-		}
-		if inFlightResponse != nil {
-			inFlightResponse.cancelCtx()
-		}
-		if !c.hijacked() {
-			if inFlightResponse != nil {
-				inFlightResponse.conn.r.abortPendingRead()
-				inFlightResponse.reqBody.Close()
-			}
-			c.close()
-			c.setState(c.rwc, StateClosed, runHooks)
-		}
-	}()
-
-	if tlsConn, ok := c.rwc.(*tls.Conn); ok {
-		tlsTO := c.server.tlsHandshakeTimeout()
-		if tlsTO > 0 {
-			dl := time.Now().Add(tlsTO)
-			c.rwc.SetReadDeadline(dl)
-			c.rwc.SetWriteDeadline(dl)
-		}
-		if err := tlsConn.HandshakeContext(ctx); err != nil {
-			// If the handshake failed due to the client not speaking
-			// TLS, assume they're speaking plaintext HTTP and write a
-			// 400 response on the TLS conn's underlying net.Conn.
-			if re, ok := err.(tls.RecordHeaderError); ok && re.Conn != nil && tlsRecordHeaderLooksLikeHTTP(re.RecordHeader) {
-				io.WriteString(re.Conn, "HTTP/1.0 400 Bad Request\r\n\r\nClient sent an HTTP request to an HTTPS server.\n")
-				re.Conn.Close()
-				return
-			}
-			c.server.logf("http: TLS handshake error from %s: %v", c.rwc.RemoteAddr(), err)
-			return
-		}
-		// Restore Conn-level deadlines.
-		if tlsTO > 0 {
-			c.rwc.SetReadDeadline(time.Time{})
-			c.rwc.SetWriteDeadline(time.Time{})
-		}
-		c.tlsState = new(tls.ConnectionState)
-		*c.tlsState = tlsConn.ConnectionState()
-		if proto := c.tlsState.NegotiatedProtocol; validNextProto(proto) {
-			if fn := c.server.TLSNextProto[proto]; fn != nil {
-				h := initALPNRequest{ctx, tlsConn, serverHandler{c.server}}
-				// Mark freshly created HTTP/2 as active and prevent any server state hooks
-				// from being run on these connections. This prevents closeIdleConns from
-				// closing such connections. See issue https://golang.org/issue/39776.
-				c.setState(c.rwc, StateActive, skipHooks)
-				fn(c.server, tlsConn, h)
-			}
-			return
-		}
-	}
-
-	// HTTP/1.x from here on.
-
-	ctx, cancelCtx := context.WithCancel(ctx)
-	c.cancelCtx = cancelCtx
-	defer cancelCtx()
-
-	c.r = &connReader{conn: c}
-	c.bufr = newBufioReader(c.r)
-	c.bufw = newBufioWriterSize(checkConnErrorWriter{c}, 4<<10)
-
-	for {
-		w, err := c.readRequest(ctx)
-		if c.r.remain != c.server.initialReadLimitSize() {
-			// If we read any bytes off the wire, we're active.
-			c.setState(c.rwc, StateActive, runHooks)
-		}
-		if err != nil {
-			const errorHeaders = "\r\nContent-Type: text/plain; charset=utf-8\r\nConnection: close\r\n\r\n"
-
-			switch {
-			case err == errTooLarge:
-				// Their HTTP client may or may not be
-				// able to read this if we're
-				// responding to them and hanging up
-				// while they're still writing their
-				// request. Undefined behavior.
-				const publicErr = "431 Request Header Fields Too Large"
-				fmt.Fprintf(c.rwc, "HTTP/1.1 "+publicErr+errorHeaders+publicErr)
-				c.closeWriteAndWait()
-				return
-
-			case isUnsupportedTEError(err):
-				// Respond as per RFC 7230 Section 3.3.1 which says,
-				//      A server that receives a request message with a
-				//      transfer coding it does not understand SHOULD
-				//      respond with 501 (Unimplemented).
-				code := StatusNotImplemented
-
-				// We purposefully aren't echoing back the transfer-encoding's value,
-				// so as to mitigate the risk of cross side scripting by an attacker.
-				fmt.Fprintf(c.rwc, "HTTP/1.1 %d %s%sUnsupported transfer encoding", code, StatusText(code), errorHeaders)
-				return
-
-			case isCommonNetReadError(err):
-				return // don't reply
-
-			default:
-				if v, ok := err.(statusError); ok {
-					fmt.Fprintf(c.rwc, "HTTP/1.1 %d %s: %s%s%d %s: %s", v.code, StatusText(v.code), v.text, errorHeaders, v.code, StatusText(v.code), v.text)
-					return
-				}
-				publicErr := "400 Bad Request"
-				fmt.Fprintf(c.rwc, "HTTP/1.1 "+publicErr+errorHeaders+publicErr)
-				return
-			}
-		}
-
-		// Expect 100 Continue support
-		req := w.req
-		if req.expectsContinue() {
-			if req.ProtoAtLeast(1, 1) && req.ContentLength != 0 {
-				// Wrap the Body reader with one that replies on the connection
-				req.Body = &expectContinueReader{readCloser: req.Body, resp: w}
-				w.canWriteContinue.setTrue()
-			}
-		} else if req.Header.get("Expect") != "" {
-			w.sendExpectationFailed()
-			return
-		}
-
-		c.curReq.Store(w)
-
-		if requestBodyRemains(req.Body) {
-			registerOnHitEOF(req.Body, w.conn.r.startBackgroundRead)
-		} else {
-			w.conn.r.startBackgroundRead()
-		}
-
-		// HTTP cannot have multiple simultaneous active requests.[*]
-		// Until the server replies to this request, it can't read another,
-		// so we might as well run the handler in this goroutine.
-		// [*] Not strictly true: HTTP pipelining. We could let them all process
-		// in parallel even if their responses need to be serialized.
-		// But we're not going to implement HTTP pipelining because it
-		// was never deployed in the wild and the answer is HTTP/2.
-		inFlightResponse = w
-		serverHandler{c.server}.ServeHTTP(w, w.req)
-		inFlightResponse = nil
-		w.cancelCtx()
-		if c.hijacked() {
-			return
-		}
-		w.finishRequest()
-		if !w.shouldReuseConnection() {
-			if w.requestBodyLimitHit || w.closedRequestBodyEarly() {
-				c.closeWriteAndWait()
-			}
-			return
-		}
-		c.setState(c.rwc, StateIdle, runHooks)
-		c.curReq.Store((*response)(nil))
-
-		if !w.conn.server.doKeepAlives() {
-			// We're in shutdown mode. We might've replied
-			// to the user without "Connection: close" and
-			// they might think they can send another
-			// request, but such is life with HTTP/1.1.
-			return
-		}
-
-		if d := c.server.idleTimeout(); d != 0 {
-			c.rwc.SetReadDeadline(time.Now().Add(d))
-			if _, err := c.bufr.Peek(4); err != nil {
-				return
-			}
-		}
-		c.rwc.SetReadDeadline(time.Time{})
-	}
-}
-
-func (w *response) sendExpectationFailed() {
-	// TODO(bradfitz): let ServeHTTP handlers handle
-	// requests with non-standard expectation[s]? Seems
-	// theoretical at best, and doesn't fit into the
-	// current ServeHTTP model anyway. We'd need to
-	// make the ResponseWriter an optional
-	// "ExpectReplier" interface or something.
-	//
-	// For now we'll just obey RFC 7231 5.1.1 which says
-	// "A server that receives an Expect field-value other
-	// than 100-continue MAY respond with a 417 (Expectation
-	// Failed) status code to indicate that the unexpected
-	// expectation cannot be met."
-	w.Header().Set("Connection", "close")
-	w.WriteHeader(StatusExpectationFailed)
-	w.finishRequest()
-}
-
-// Hijack implements the Hijacker.Hijack method. Our response is both a ResponseWriter
-// and a Hijacker.
-func (w *response) Hijack() (rwc net.Conn, buf *bufio.ReadWriter, err error) {
-	if w.handlerDone.isSet() {
-		panic("net/http: Hijack called after ServeHTTP finished")
-	}
-	if w.wroteHeader {
-		w.cw.flush()
-	}
-
-	c := w.conn
-	c.mu.Lock()
-	defer c.mu.Unlock()
-
-	// Release the bufioWriter that writes to the chunk writer, it is not
-	// used after a connection has been hijacked.
-	rwc, buf, err = c.hijackLocked()
-	if err == nil {
-		putBufioWriter(w.w)
-		w.w = nil
-	}
-	return rwc, buf, err
-}
-
-func (w *response) CloseNotify() <-chan bool {
-	if w.handlerDone.isSet() {
-		panic("net/http: CloseNotify called after ServeHTTP finished")
-	}
-	return w.closeNotifyCh
-}
-
-func registerOnHitEOF(rc io.ReadCloser, fn func()) {
-	switch v := rc.(type) {
-	case *expectContinueReader:
-		registerOnHitEOF(v.readCloser, fn)
-	case *body:
-		v.registerOnHitEOF(fn)
-	default:
-		panic("unexpected type " + fmt.Sprintf("%T", rc))
-	}
-}
-
-// requestBodyRemains reports whether future calls to Read
-// on rc might yield more data.
-func requestBodyRemains(rc io.ReadCloser) bool {
-	if rc == NoBody {
-		return false
-	}
-	switch v := rc.(type) {
-	case *expectContinueReader:
-		return requestBodyRemains(v.readCloser)
-	case *body:
-		return v.bodyRemains()
-	default:
-		panic("unexpected type " + fmt.Sprintf("%T", rc))
-	}
-}
-
-// The HandlerFunc type is an adapter to allow the use of
-// ordinary functions as HTTP handlers. If f is a function
-// with the appropriate signature, HandlerFunc(f) is a
-// Handler that calls f.
-type HandlerFunc func(ResponseWriter, *Request)
-
-// ServeHTTP calls f(w, r).
-func (f HandlerFunc) ServeHTTP(w ResponseWriter, r *Request) {
-	f(w, r)
-}
-
-// Helper handlers
-
-// Error replies to the request with the specified error message and HTTP code.
-// It does not otherwise end the request; the caller should ensure no further
-// writes are done to w.
-// The error message should be plain text.
-func Error(w ResponseWriter, error string, code int) {
-	w.Header().Set("Content-Type", "text/plain; charset=utf-8")
-	w.Header().Set("X-Content-Type-Options", "nosniff")
-	w.WriteHeader(code)
-	fmt.Fprintln(w, error)
-}
-
-// NotFound replies to the request with an HTTP 404 not found error.
-func NotFound(w ResponseWriter, r *Request) { Error(w, "404 page not found", StatusNotFound) }
-
-// NotFoundHandler returns a simple request handler
-// that replies to each request with a ``404 page not found'' reply.
-func NotFoundHandler() Handler { return HandlerFunc(NotFound) }
-
-// StripPrefix returns a handler that serves HTTP requests by removing the
-// given prefix from the request URL's Path (and RawPath if set) and invoking
-// the handler h. StripPrefix handles a request for a path that doesn't begin
-// with prefix by replying with an HTTP 404 not found error. The prefix must
-// match exactly: if the prefix in the request contains escaped characters
-// the reply is also an HTTP 404 not found error.
-func StripPrefix(prefix string, h Handler) Handler {
-	if prefix == "" {
-		return h
-	}
-	return HandlerFunc(func(w ResponseWriter, r *Request) {
-		p := strings.TrimPrefix(r.URL.Path, prefix)
-		rp := strings.TrimPrefix(r.URL.RawPath, prefix)
-		if len(p) < len(r.URL.Path) && (r.URL.RawPath == "" || len(rp) < len(r.URL.RawPath)) {
-			r2 := new(Request)
-			*r2 = *r
-			r2.URL = new(url.URL)
-			*r2.URL = *r.URL
-			r2.URL.Path = p
-			r2.URL.RawPath = rp
-			h.ServeHTTP(w, r2)
-		} else {
-			NotFound(w, r)
-		}
-	})
-}
-
-// Redirect replies to the request with a redirect to url,
-// which may be a path relative to the request path.
-//
-// The provided code should be in the 3xx range and is usually
-// StatusMovedPermanently, StatusFound or StatusSeeOther.
-//
-// If the Content-Type header has not been set, Redirect sets it
-// to "text/html; charset=utf-8" and writes a small HTML body.
-// Setting the Content-Type header to any value, including nil,
-// disables that behavior.
-func Redirect(w ResponseWriter, r *Request, url string, code int) {
-	if u, err := urlpkg.Parse(url); err == nil {
-		// If url was relative, make its path absolute by
-		// combining with request path.
-		// The client would probably do this for us,
-		// but doing it ourselves is more reliable.
-		// See RFC 7231, section 7.1.2
-		if u.Scheme == "" && u.Host == "" {
-			oldpath := r.URL.Path
-			if oldpath == "" { // should not happen, but avoid a crash if it does
-				oldpath = "/"
-			}
-
-			// no leading http://server
-			if url == "" || url[0] != '/' {
-				// make relative path absolute
-				olddir, _ := path.Split(oldpath)
-				url = olddir + url
-			}
-
-			var query string
-			if i := strings.Index(url, "?"); i != -1 {
-				url, query = url[:i], url[i:]
-			}
-
-			// clean up but preserve trailing slash
-			trailing := strings.HasSuffix(url, "/")
-			url = path.Clean(url)
-			if trailing && !strings.HasSuffix(url, "/") {
-				url += "/"
-			}
-			url += query
-		}
-	}
-
-	h := w.Header()
-
-	// RFC 7231 notes that a short HTML body is usually included in
-	// the response because older user agents may not understand 301/307.
-	// Do it only if the request didn't already have a Content-Type header.
-	_, hadCT := h["Content-Type"]
-
-	h.Set("Location", hexEscapeNonASCII(url))
-	if !hadCT && (r.Method == "GET" || r.Method == "HEAD") {
-		h.Set("Content-Type", "text/html; charset=utf-8")
-	}
-	w.WriteHeader(code)
-
-	// Shouldn't send the body for POST or HEAD; that leaves GET.
-	if !hadCT && r.Method == "GET" {
-		body := "<a href=\"" + htmlEscape(url) + "\">" + statusText[code] + "</a>.\n"
-		fmt.Fprintln(w, body)
-	}
-}
-
-var htmlReplacer = strings.NewReplacer(
-	"&", "&amp;",
-	"<", "&lt;",
-	">", "&gt;",
-	// "&#34;" is shorter than "&quot;".
-	`"`, "&#34;",
-	// "&#39;" is shorter than "&apos;" and apos was not in HTML until HTML5.
-	"'", "&#39;",
-)
-
-func htmlEscape(s string) string {
-	return htmlReplacer.Replace(s)
-}
-
-// Redirect to a fixed URL
-type redirectHandler struct {
-	url  string
-	code int
-}
-
-func (rh *redirectHandler) ServeHTTP(w ResponseWriter, r *Request) {
-	Redirect(w, r, rh.url, rh.code)
-}
-
-// RedirectHandler returns a request handler that redirects
-// each request it receives to the given url using the given
-// status code.
-//
-// The provided code should be in the 3xx range and is usually
-// StatusMovedPermanently, StatusFound or StatusSeeOther.
-func RedirectHandler(url string, code int) Handler {
-	return &redirectHandler{url, code}
-}
-
-// ServeMux is an HTTP request multiplexer.
-// It matches the URL of each incoming request against a list of registered
-// patterns and calls the handler for the pattern that
-// most closely matches the URL.
-//
-// Patterns name fixed, rooted paths, like "/favicon.ico",
-// or rooted subtrees, like "/images/" (note the trailing slash).
-// Longer patterns take precedence over shorter ones, so that
-// if there are handlers registered for both "/images/"
-// and "/images/thumbnails/", the latter handler will be
-// called for paths beginning "/images/thumbnails/" and the
-// former will receive requests for any other paths in the
-// "/images/" subtree.
-//
-// Note that since a pattern ending in a slash names a rooted subtree,
-// the pattern "/" matches all paths not matched by other registered
-// patterns, not just the URL with Path == "/".
-//
-// If a subtree has been registered and a request is received naming the
-// subtree root without its trailing slash, ServeMux redirects that
-// request to the subtree root (adding the trailing slash). This behavior can
-// be overridden with a separate registration for the path without
-// the trailing slash. For example, registering "/images/" causes ServeMux
-// to redirect a request for "/images" to "/images/", unless "/images" has
-// been registered separately.
-//
-// Patterns may optionally begin with a host name, restricting matches to
-// URLs on that host only. Host-specific patterns take precedence over
-// general patterns, so that a handler might register for the two patterns
-// "/codesearch" and "codesearch.google.com/" without also taking over
-// requests for "http://www.google.com/".
-//
-// ServeMux also takes care of sanitizing the URL request path and the Host
-// header, stripping the port number and redirecting any request containing . or
-// .. elements or repeated slashes to an equivalent, cleaner URL.
-type ServeMux struct {
-	mu    sync.RWMutex
-	m     map[string]muxEntry
-	es    []muxEntry // slice of entries sorted from longest to shortest.
-	hosts bool       // whether any patterns contain hostnames
-}
-
-type muxEntry struct {
-	h       Handler
-	pattern string
-}
-
-// NewServeMux allocates and returns a new ServeMux.
-func NewServeMux() *ServeMux { return new(ServeMux) }
-
-// DefaultServeMux is the default ServeMux used by Serve.
-var DefaultServeMux = &defaultServeMux
-
-var defaultServeMux ServeMux
-
-// cleanPath returns the canonical path for p, eliminating . and .. elements.
-func cleanPath(p string) string {
-	if p == "" {
-		return "/"
-	}
-	if p[0] != '/' {
-		p = "/" + p
-	}
-	np := path.Clean(p)
-	// path.Clean removes trailing slash except for root;
-	// put the trailing slash back if necessary.
-	if p[len(p)-1] == '/' && np != "/" {
-		// Fast path for common case of p being the string we want:
-		if len(p) == len(np)+1 && strings.HasPrefix(p, np) {
-			np = p
-		} else {
-			np += "/"
-		}
-	}
-	return np
-}
-
-// stripHostPort returns h without any trailing ":<port>".
-func stripHostPort(h string) string {
-	// If no port on host, return unchanged
-	if !strings.Contains(h, ":") {
-		return h
-	}
-	host, _, err := net.SplitHostPort(h)
-	if err != nil {
-		return h // on error, return unchanged
-	}
-	return host
-}
-
-// Find a handler on a handler map given a path string.
-// Most-specific (longest) pattern wins.
-func (mux *ServeMux) match(path string) (h Handler, pattern string) {
-	// Check for exact match first.
-	v, ok := mux.m[path]
-	if ok {
-		return v.h, v.pattern
-	}
-
-	// Check for longest valid match.  mux.es contains all patterns
-	// that end in / sorted from longest to shortest.
-	for _, e := range mux.es {
-		if strings.HasPrefix(path, e.pattern) {
-			return e.h, e.pattern
-		}
-	}
-	return nil, ""
-}
-
-// redirectToPathSlash determines if the given path needs appending "/" to it.
-// This occurs when a handler for path + "/" was already registered, but
-// not for path itself. If the path needs appending to, it creates a new
-// URL, setting the path to u.Path + "/" and returning true to indicate so.
-func (mux *ServeMux) redirectToPathSlash(host, path string, u *url.URL) (*url.URL, bool) {
-	mux.mu.RLock()
-	shouldRedirect := mux.shouldRedirectRLocked(host, path)
-	mux.mu.RUnlock()
-	if !shouldRedirect {
-		return u, false
-	}
-	path = path + "/"
-	u = &url.URL{Path: path, RawQuery: u.RawQuery}
-	return u, true
-}
-
-// shouldRedirectRLocked reports whether the given path and host should be redirected to
-// path+"/". This should happen if a handler is registered for path+"/" but
-// not path -- see comments at ServeMux.
-func (mux *ServeMux) shouldRedirectRLocked(host, path string) bool {
-	p := []string{path, host + path}
-
-	for _, c := range p {
-		if _, exist := mux.m[c]; exist {
-			return false
-		}
-	}
-
-	n := len(path)
-	if n == 0 {
-		return false
-	}
-	for _, c := range p {
-		if _, exist := mux.m[c+"/"]; exist {
-			return path[n-1] != '/'
-		}
-	}
-
-	return false
-}
-
-// Handler returns the handler to use for the given request,
-// consulting r.Method, r.Host, and r.URL.Path. It always returns
-// a non-nil handler. If the path is not in its canonical form, the
-// handler will be an internally-generated handler that redirects
-// to the canonical path. If the host contains a port, it is ignored
-// when matching handlers.
-//
-// The path and host are used unchanged for CONNECT requests.
-//
-// Handler also returns the registered pattern that matches the
-// request or, in the case of internally-generated redirects,
-// the pattern that will match after following the redirect.
-//
-// If there is no registered handler that applies to the request,
-// Handler returns a ``page not found'' handler and an empty pattern.
-func (mux *ServeMux) Handler(r *Request) (h Handler, pattern string) {
-
-	// CONNECT requests are not canonicalized.
-	if r.Method == "CONNECT" {
-		// If r.URL.Path is /tree and its handler is not registered,
-		// the /tree -> /tree/ redirect applies to CONNECT requests
-		// but the path canonicalization does not.
-		if u, ok := mux.redirectToPathSlash(r.URL.Host, r.URL.Path, r.URL); ok {
-			return RedirectHandler(u.String(), StatusMovedPermanently), u.Path
-		}
-
-		return mux.handler(r.Host, r.URL.Path)
-	}
-
-	// All other requests have any port stripped and path cleaned
-	// before passing to mux.handler.
-	host := stripHostPort(r.Host)
-	path := cleanPath(r.URL.Path)
-
-	// If the given path is /tree and its handler is not registered,
-	// redirect for /tree/.
-	if u, ok := mux.redirectToPathSlash(host, path, r.URL); ok {
-		return RedirectHandler(u.String(), StatusMovedPermanently), u.Path
-	}
-
-	if path != r.URL.Path {
-		_, pattern = mux.handler(host, path)
-		u := &url.URL{Path: path, RawQuery: r.URL.RawQuery}
-		return RedirectHandler(u.String(), StatusMovedPermanently), pattern
-	}
-
-	return mux.handler(host, r.URL.Path)
-}
-
-// handler is the main implementation of Handler.
-// The path is known to be in canonical form, except for CONNECT methods.
-func (mux *ServeMux) handler(host, path string) (h Handler, pattern string) {
-	mux.mu.RLock()
-	defer mux.mu.RUnlock()
-
-	// Host-specific pattern takes precedence over generic ones
-	if mux.hosts {
-		h, pattern = mux.match(host + path)
-	}
-	if h == nil {
-		h, pattern = mux.match(path)
-	}
-	if h == nil {
-		h, pattern = NotFoundHandler(), ""
-	}
-	return
-}
-
-// ServeHTTP dispatches the request to the handler whose
-// pattern most closely matches the request URL.
-func (mux *ServeMux) ServeHTTP(w ResponseWriter, r *Request) {
-	if r.RequestURI == "*" {
-		if r.ProtoAtLeast(1, 1) {
-			w.Header().Set("Connection", "close")
-		}
-		w.WriteHeader(StatusBadRequest)
-		return
-	}
-	h, _ := mux.Handler(r)
-	h.ServeHTTP(w, r)
-}
-
-// Handle registers the handler for the given pattern.
-// If a handler already exists for pattern, Handle panics.
-func (mux *ServeMux) Handle(pattern string, handler Handler) {
-	mux.mu.Lock()
-	defer mux.mu.Unlock()
-
-	if pattern == "" {
-		panic("http: invalid pattern")
-	}
-	if handler == nil {
-		panic("http: nil handler")
-	}
-	if _, exist := mux.m[pattern]; exist {
-		panic("http: multiple registrations for " + pattern)
-	}
-
-	if mux.m == nil {
-		mux.m = make(map[string]muxEntry)
-	}
-	e := muxEntry{h: handler, pattern: pattern}
-	mux.m[pattern] = e
-	if pattern[len(pattern)-1] == '/' {
-		mux.es = appendSorted(mux.es, e)
-	}
-
-	if pattern[0] != '/' {
-		mux.hosts = true
-	}
-}
-
-func appendSorted(es []muxEntry, e muxEntry) []muxEntry {
-	n := len(es)
-	i := sort.Search(n, func(i int) bool {
-		return len(es[i].pattern) < len(e.pattern)
-	})
-	if i == n {
-		return append(es, e)
-	}
-	// we now know that i points at where we want to insert
-	es = append(es, muxEntry{}) // try to grow the slice in place, any entry works.
-	copy(es[i+1:], es[i:])      // Move shorter entries down
-	es[i] = e
-	return es
-}
-
-// HandleFunc registers the handler function for the given pattern.
-func (mux *ServeMux) HandleFunc(pattern string, handler func(ResponseWriter, *Request)) {
-	if handler == nil {
-		panic("http: nil handler")
-	}
-	mux.Handle(pattern, HandlerFunc(handler))
-}
-
-// Handle registers the handler for the given pattern
-// in the DefaultServeMux.
-// The documentation for ServeMux explains how patterns are matched.
-func Handle(pattern string, handler Handler) { DefaultServeMux.Handle(pattern, handler) }
-
-// HandleFunc registers the handler function for the given pattern
-// in the DefaultServeMux.
-// The documentation for ServeMux explains how patterns are matched.
-func HandleFunc(pattern string, handler func(ResponseWriter, *Request)) {
-	DefaultServeMux.HandleFunc(pattern, handler)
-}
-
-// Serve accepts incoming HTTP connections on the listener l,
-// creating a new service goroutine for each. The service goroutines
-// read requests and then call handler to reply to them.
-//
-// The handler is typically nil, in which case the DefaultServeMux is used.
-//
-// HTTP/2 support is only enabled if the Listener returns *tls.Conn
-// connections and they were configured with "h2" in the TLS
-// Config.NextProtos.
-//
-// Serve always returns a non-nil error.
-func Serve(l net.Listener, handler Handler) error {
-	srv := &Server{Handler: handler}
-	return srv.Serve(l)
-}
-
-// ServeTLS accepts incoming HTTPS connections on the listener l,
-// creating a new service goroutine for each. The service goroutines
-// read requests and then call handler to reply to them.
-//
-// The handler is typically nil, in which case the DefaultServeMux is used.
-//
-// Additionally, files containing a certificate and matching private key
-// for the server must be provided. If the certificate is signed by a
-// certificate authority, the certFile should be the concatenation
-// of the server's certificate, any intermediates, and the CA's certificate.
-//
-// ServeTLS always returns a non-nil error.
-func ServeTLS(l net.Listener, handler Handler, certFile, keyFile string) error {
-	srv := &Server{Handler: handler}
-	return srv.ServeTLS(l, certFile, keyFile)
-}
-
-// A Server defines parameters for running an HTTP server.
-// The zero value for Server is a valid configuration.
-type Server struct {
-	// Addr optionally specifies the TCP address for the server to listen on,
-	// in the form "host:port". If empty, ":http" (port 80) is used.
-	// The service names are defined in RFC 6335 and assigned by IANA.
-	// See net.Dial for details of the address format.
-	Addr string
-
-	Handler Handler // handler to invoke, http.DefaultServeMux if nil
-
-	// TLSConfig optionally provides a TLS configuration for use
-	// by ServeTLS and ListenAndServeTLS. Note that this value is
-	// cloned by ServeTLS and ListenAndServeTLS, so it's not
-	// possible to modify the configuration with methods like
-	// tls.Config.SetSessionTicketKeys. To use
-	// SetSessionTicketKeys, use Server.Serve with a TLS Listener
-	// instead.
-	TLSConfig *tls.Config
-
-	// ReadTimeout is the maximum duration for reading the entire
-	// request, including the body. A zero or negative value means
-	// there will be no timeout.
-	//
-	// Because ReadTimeout does not let Handlers make per-request
-	// decisions on each request body's acceptable deadline or
-	// upload rate, most users will prefer to use
-	// ReadHeaderTimeout. It is valid to use them both.
-	ReadTimeout time.Duration
-
-	// ReadHeaderTimeout is the amount of time allowed to read
-	// request headers. The connection's read deadline is reset
-	// after reading the headers and the Handler can decide what
-	// is considered too slow for the body. If ReadHeaderTimeout
-	// is zero, the value of ReadTimeout is used. If both are
-	// zero, there is no timeout.
-	ReadHeaderTimeout time.Duration
-
-	// WriteTimeout is the maximum duration before timing out
-	// writes of the response. It is reset whenever a new
-	// request's header is read. Like ReadTimeout, it does not
-	// let Handlers make decisions on a per-request basis.
-	// A zero or negative value means there will be no timeout.
-	WriteTimeout time.Duration
-
-	// IdleTimeout is the maximum amount of time to wait for the
-	// next request when keep-alives are enabled. If IdleTimeout
-	// is zero, the value of ReadTimeout is used. If both are
-	// zero, there is no timeout.
-	IdleTimeout time.Duration
-
-	// MaxHeaderBytes controls the maximum number of bytes the
-	// server will read parsing the request header's keys and
-	// values, including the request line. It does not limit the
-	// size of the request body.
-	// If zero, DefaultMaxHeaderBytes is used.
-	MaxHeaderBytes int
-
-	// TLSNextProto optionally specifies a function to take over
-	// ownership of the provided TLS connection when an ALPN
-	// protocol upgrade has occurred. The map key is the protocol
-	// name negotiated. The Handler argument should be used to
-	// handle HTTP requests and will initialize the Request's TLS
-	// and RemoteAddr if not already set. The connection is
-	// automatically closed when the function returns.
-	// If TLSNextProto is not nil, HTTP/2 support is not enabled
-	// automatically.
-	TLSNextProto map[string]func(*Server, *tls.Conn, Handler)
-
-	// ConnState specifies an optional callback function that is
-	// called when a client connection changes state. See the
-	// ConnState type and associated constants for details.
-	ConnState func(net.Conn, ConnState)
-
-	// ErrorLog specifies an optional logger for errors accepting
-	// connections, unexpected behavior from handlers, and
-	// underlying FileSystem errors.
-	// If nil, logging is done via the log package's standard logger.
-	ErrorLog *log.Logger
-
-	// BaseContext optionally specifies a function that returns
-	// the base context for incoming requests on this server.
-	// The provided Listener is the specific Listener that's
-	// about to start accepting requests.
-	// If BaseContext is nil, the default is context.Background().
-	// If non-nil, it must return a non-nil context.
-	BaseContext func(net.Listener) context.Context
-
-	// ConnContext optionally specifies a function that modifies
-	// the context used for a new connection c. The provided ctx
-	// is derived from the base context and has a ServerContextKey
-	// value.
-	ConnContext func(ctx context.Context, c net.Conn) context.Context
-
-	inShutdown atomicBool // true when server is in shutdown
-
-	disableKeepAlives int32     // accessed atomically.
-	nextProtoOnce     sync.Once // guards setupHTTP2_* init
-	nextProtoErr      error     // result of http2.ConfigureServer if used
-
-	mu         sync.Mutex
-	listeners  map[*net.Listener]struct{}
-	activeConn map[*conn]struct{}
-	doneChan   chan struct{}
-	onShutdown []func()
-}
-
-func (s *Server) getDoneChan() <-chan struct{} {
-	s.mu.Lock()
-	defer s.mu.Unlock()
-	return s.getDoneChanLocked()
-}
-
-func (s *Server) getDoneChanLocked() chan struct{} {
-	if s.doneChan == nil {
-		s.doneChan = make(chan struct{})
-	}
-	return s.doneChan
-}
-
-func (s *Server) closeDoneChanLocked() {
-	ch := s.getDoneChanLocked()
-	select {
-	case <-ch:
-		// Already closed. Don't close again.
-	default:
-		// Safe to close here. We're the only closer, guarded
-		// by s.mu.
-		close(ch)
-	}
-}
-
-// Close immediately closes all active net.Listeners and any
-// connections in state StateNew, StateActive, or StateIdle. For a
-// graceful shutdown, use Shutdown.
-//
-// Close does not attempt to close (and does not even know about)
-// any hijacked connections, such as WebSockets.
-//
-// Close returns any error returned from closing the Server's
-// underlying Listener(s).
-func (srv *Server) Close() error {
-	srv.inShutdown.setTrue()
-	srv.mu.Lock()
-	defer srv.mu.Unlock()
-	srv.closeDoneChanLocked()
-	err := srv.closeListenersLocked()
-	for c := range srv.activeConn {
-		c.rwc.Close()
-		delete(srv.activeConn, c)
-	}
-	return err
-}
-
-// shutdownPollIntervalMax is the max polling interval when checking
-// quiescence during Server.Shutdown. Polling starts with a small
-// interval and backs off to the max.
-// Ideally we could find a solution that doesn't involve polling,
-// but which also doesn't have a high runtime cost (and doesn't
-// involve any contentious mutexes), but that is left as an
-// exercise for the reader.
-const shutdownPollIntervalMax = 500 * time.Millisecond
-
-// Shutdown gracefully shuts down the server without interrupting any
-// active connections. Shutdown works by first closing all open
-// listeners, then closing all idle connections, and then waiting
-// indefinitely for connections to return to idle and then shut down.
-// If the provided context expires before the shutdown is complete,
-// Shutdown returns the context's error, otherwise it returns any
-// error returned from closing the Server's underlying Listener(s).
-//
-// When Shutdown is called, Serve, ListenAndServe, and
-// ListenAndServeTLS immediately return ErrServerClosed. Make sure the
-// program doesn't exit and waits instead for Shutdown to return.
-//
-// Shutdown does not attempt to close nor wait for hijacked
-// connections such as WebSockets. The caller of Shutdown should
-// separately notify such long-lived connections of shutdown and wait
-// for them to close, if desired. See RegisterOnShutdown for a way to
-// register shutdown notification functions.
-//
-// Once Shutdown has been called on a server, it may not be reused;
-// future calls to methods such as Serve will return ErrServerClosed.
-func (srv *Server) Shutdown(ctx context.Context) error {
-	srv.inShutdown.setTrue()
-
-	srv.mu.Lock()
-	lnerr := srv.closeListenersLocked()
-	srv.closeDoneChanLocked()
-	for _, f := range srv.onShutdown {
-		go f()
-	}
-	srv.mu.Unlock()
-
-	pollIntervalBase := time.Millisecond
-	nextPollInterval := func() time.Duration {
-		// Add 10% jitter.
-		interval := pollIntervalBase + time.Duration(rand.Intn(int(pollIntervalBase/10)))
-		// Double and clamp for next time.
-		pollIntervalBase *= 2
-		if pollIntervalBase > shutdownPollIntervalMax {
-			pollIntervalBase = shutdownPollIntervalMax
-		}
-		return interval
-	}
-
-	timer := time.NewTimer(nextPollInterval())
-	defer timer.Stop()
-	for {
-		if srv.closeIdleConns() && srv.numListeners() == 0 {
-			return lnerr
-		}
-		select {
-		case <-ctx.Done():
-			return ctx.Err()
-		case <-timer.C:
-			timer.Reset(nextPollInterval())
-		}
-	}
-}
-
-// RegisterOnShutdown registers a function to call on Shutdown.
-// This can be used to gracefully shutdown connections that have
-// undergone ALPN protocol upgrade or that have been hijacked.
-// This function should start protocol-specific graceful shutdown,
-// but should not wait for shutdown to complete.
-func (srv *Server) RegisterOnShutdown(f func()) {
-	srv.mu.Lock()
-	srv.onShutdown = append(srv.onShutdown, f)
-	srv.mu.Unlock()
-}
-
-func (s *Server) numListeners() int {
-	s.mu.Lock()
-	defer s.mu.Unlock()
-	return len(s.listeners)
-}
-
-// closeIdleConns closes all idle connections and reports whether the
-// server is quiescent.
-func (s *Server) closeIdleConns() bool {
-	s.mu.Lock()
-	defer s.mu.Unlock()
-	quiescent := true
-	for c := range s.activeConn {
-		st, unixSec := c.getState()
-		// Issue 22682: treat StateNew connections as if
-		// they're idle if we haven't read the first request's
-		// header in over 5 seconds.
-		if st == StateNew && unixSec < time.Now().Unix()-5 {
-			st = StateIdle
-		}
-		if st != StateIdle || unixSec == 0 {
-			// Assume unixSec == 0 means it's a very new
-			// connection, without state set yet.
-			quiescent = false
-			continue
-		}
-		c.rwc.Close()
-		delete(s.activeConn, c)
-	}
-	return quiescent
-}
-
-func (s *Server) closeListenersLocked() error {
-	var err error
-	for ln := range s.listeners {
-		if cerr := (*ln).Close(); cerr != nil && err == nil {
-			err = cerr
-		}
-	}
-	return err
-}
-
-// A ConnState represents the state of a client connection to a server.
-// It's used by the optional Server.ConnState hook.
-type ConnState int
-
-const (
-	// StateNew represents a new connection that is expected to
-	// send a request immediately. Connections begin at this
-	// state and then transition to either StateActive or
-	// StateClosed.
-	StateNew ConnState = iota
-
-	// StateActive represents a connection that has read 1 or more
-	// bytes of a request. The Server.ConnState hook for
-	// StateActive fires before the request has entered a handler
-	// and doesn't fire again until the request has been
-	// handled. After the request is handled, the state
-	// transitions to StateClosed, StateHijacked, or StateIdle.
-	// For HTTP/2, StateActive fires on the transition from zero
-	// to one active request, and only transitions away once all
-	// active requests are complete. That means that ConnState
-	// cannot be used to do per-request work; ConnState only notes
-	// the overall state of the connection.
-	StateActive
-
-	// StateIdle represents a connection that has finished
-	// handling a request and is in the keep-alive state, waiting
-	// for a new request. Connections transition from StateIdle
-	// to either StateActive or StateClosed.
-	StateIdle
-
-	// StateHijacked represents a hijacked connection.
-	// This is a terminal state. It does not transition to StateClosed.
-	StateHijacked
-
-	// StateClosed represents a closed connection.
-	// This is a terminal state. Hijacked connections do not
-	// transition to StateClosed.
-	StateClosed
-)
-
-var stateName = map[ConnState]string{
-	StateNew:      "new",
-	StateActive:   "active",
-	StateIdle:     "idle",
-	StateHijacked: "hijacked",
-	StateClosed:   "closed",
-}
-
-func (c ConnState) String() string {
-	return stateName[c]
-}
-
-// serverHandler delegates to either the server's Handler or
-// DefaultServeMux and also handles "OPTIONS *" requests.
-type serverHandler struct {
-	srv *Server
-}
-
-func (sh serverHandler) ServeHTTP(rw ResponseWriter, req *Request) {
-	handler := sh.srv.Handler
-	if handler == nil {
-		handler = DefaultServeMux
-	}
-	if req.RequestURI == "*" && req.Method == "OPTIONS" {
-		handler = globalOptionsHandler{}
-	}
-
-	if req.URL != nil && strings.Contains(req.URL.RawQuery, ";") {
-		var allowQuerySemicolonsInUse int32
-		req = req.WithContext(context.WithValue(req.Context(), silenceSemWarnContextKey, func() {
-			atomic.StoreInt32(&allowQuerySemicolonsInUse, 1)
-		}))
-		defer func() {
-			if atomic.LoadInt32(&allowQuerySemicolonsInUse) == 0 {
-				sh.srv.logf("http: URL query contains semicolon, which is no longer a supported separator; parts of the query may be stripped when parsed; see golang.org/issue/25192")
-			}
-		}()
-	}
-
-	handler.ServeHTTP(rw, req)
-}
-
-var silenceSemWarnContextKey = &contextKey{"silence-semicolons"}
-
-// AllowQuerySemicolons returns a handler that serves requests by converting any
-// unescaped semicolons in the URL query to ampersands, and invoking the handler h.
-//
-// This restores the pre-Go 1.17 behavior of splitting query parameters on both
-// semicolons and ampersands. (See golang.org/issue/25192). Note that this
-// behavior doesn't match that of many proxies, and the mismatch can lead to
-// security issues.
-//
-// AllowQuerySemicolons should be invoked before Request.ParseForm is called.
-func AllowQuerySemicolons(h Handler) Handler {
-	return HandlerFunc(func(w ResponseWriter, r *Request) {
-		if silenceSemicolonsWarning, ok := r.Context().Value(silenceSemWarnContextKey).(func()); ok {
-			silenceSemicolonsWarning()
-		}
-		if strings.Contains(r.URL.RawQuery, ";") {
-			r2 := new(Request)
-			*r2 = *r
-			r2.URL = new(url.URL)
-			*r2.URL = *r.URL
-			r2.URL.RawQuery = strings.ReplaceAll(r.URL.RawQuery, ";", "&")
-			h.ServeHTTP(w, r2)
-		} else {
-			h.ServeHTTP(w, r)
-		}
-	})
-}
-
-// ListenAndServe listens on the TCP network address srv.Addr and then
-// calls Serve to handle requests on incoming connections.
-// Accepted connections are configured to enable TCP keep-alives.
-//
-// If srv.Addr is blank, ":http" is used.
-//
-// ListenAndServe always returns a non-nil error. After Shutdown or Close,
-// the returned error is ErrServerClosed.
-func (srv *Server) ListenAndServe() error {
-	if srv.shuttingDown() {
-		return ErrServerClosed
-	}
-	addr := srv.Addr
-	if addr == "" {
-		addr = ":http"
-	}
-	ln, err := net.Listen("tcp", addr)
-	if err != nil {
-		return err
-	}
-	return srv.Serve(ln)
-}
-
-var testHookServerServe func(*Server, net.Listener) // used if non-nil
-
-// shouldDoServeHTTP2 reports whether Server.Serve should configure
-// automatic HTTP/2. (which sets up the srv.TLSNextProto map)
-func (srv *Server) shouldConfigureHTTP2ForServe() bool {
-	if srv.TLSConfig == nil {
-		// Compatibility with Go 1.6:
-		// If there's no TLSConfig, it's possible that the user just
-		// didn't set it on the http.Server, but did pass it to
-		// tls.NewListener and passed that listener to Serve.
-		// So we should configure HTTP/2 (to set up srv.TLSNextProto)
-		// in case the listener returns an "h2" *tls.Conn.
-		return true
-	}
-	// The user specified a TLSConfig on their http.Server.
-	// In this, case, only configure HTTP/2 if their tls.Config
-	// explicitly mentions "h2". Otherwise http2.ConfigureServer
-	// would modify the tls.Config to add it, but they probably already
-	// passed this tls.Config to tls.NewListener. And if they did,
-	// it's too late anyway to fix it. It would only be potentially racy.
-	// See Issue 15908.
-	return strSliceContains(srv.TLSConfig.NextProtos, http2NextProtoTLS)
-}
-
-// ErrServerClosed is returned by the Server's Serve, ServeTLS, ListenAndServe,
-// and ListenAndServeTLS methods after a call to Shutdown or Close.
-var ErrServerClosed = errors.New("http: Server closed")
-
-// Serve accepts incoming connections on the Listener l, creating a
-// new service goroutine for each. The service goroutines read requests and
-// then call srv.Handler to reply to them.
-//
-// HTTP/2 support is only enabled if the Listener returns *tls.Conn
-// connections and they were configured with "h2" in the TLS
-// Config.NextProtos.
-//
-// Serve always returns a non-nil error and closes l.
-// After Shutdown or Close, the returned error is ErrServerClosed.
-func (srv *Server) Serve(l net.Listener) error {
-	if fn := testHookServerServe; fn != nil {
-		fn(srv, l) // call hook with unwrapped listener
-	}
-
-	origListener := l
-	l = &onceCloseListener{Listener: l}
-	defer l.Close()
-
-	if err := srv.setupHTTP2_Serve(); err != nil {
-		return err
-	}
-
-	if !srv.trackListener(&l, true) {
-		return ErrServerClosed
-	}
-	defer srv.trackListener(&l, false)
-
-	baseCtx := context.Background()
-	if srv.BaseContext != nil {
-		baseCtx = srv.BaseContext(origListener)
-		if baseCtx == nil {
-			panic("BaseContext returned a nil context")
-		}
-	}
-
-	var tempDelay time.Duration // how long to sleep on accept failure
-
-	ctx := context.WithValue(baseCtx, ServerContextKey, srv)
-	for {
-		rw, err := l.Accept()
-		if err != nil {
-			select {
-			case <-srv.getDoneChan():
-				return ErrServerClosed
-			default:
-			}
-			if ne, ok := err.(net.Error); ok && ne.Temporary() {
-				if tempDelay == 0 {
-					tempDelay = 5 * time.Millisecond
-				} else {
-					tempDelay *= 2
-				}
-				if max := 1 * time.Second; tempDelay > max {
-					tempDelay = max
-				}
-				srv.logf("http: Accept error: %v; retrying in %v", err, tempDelay)
-				time.Sleep(tempDelay)
-				continue
-			}
-			return err
-		}
-		connCtx := ctx
-		if cc := srv.ConnContext; cc != nil {
-			connCtx = cc(connCtx, rw)
-			if connCtx == nil {
-				panic("ConnContext returned nil")
-			}
-		}
-		tempDelay = 0
-		c := srv.newConn(rw)
-		c.setState(c.rwc, StateNew, runHooks) // before Serve can return
-		go c.serve(connCtx)
-	}
-}
-
-// ServeTLS accepts incoming connections on the Listener l, creating a
-// new service goroutine for each. The service goroutines perform TLS
-// setup and then read requests, calling srv.Handler to reply to them.
-//
-// Files containing a certificate and matching private key for the
-// server must be provided if neither the Server's
-// TLSConfig.Certificates nor TLSConfig.GetCertificate are populated.
-// If the certificate is signed by a certificate authority, the
-// certFile should be the concatenation of the server's certificate,
-// any intermediates, and the CA's certificate.
-//
-// ServeTLS always returns a non-nil error. After Shutdown or Close, the
-// returned error is ErrServerClosed.
-func (srv *Server) ServeTLS(l net.Listener, certFile, keyFile string) error {
-	// Setup HTTP/2 before srv.Serve, to initialize srv.TLSConfig
-	// before we clone it and create the TLS Listener.
-	if err := srv.setupHTTP2_ServeTLS(); err != nil {
-		return err
-	}
-
-	config := cloneTLSConfig(srv.TLSConfig)
-	if !strSliceContains(config.NextProtos, "http/1.1") {
-		config.NextProtos = append(config.NextProtos, "http/1.1")
-	}
-
-	configHasCert := len(config.Certificates) > 0 || config.GetCertificate != nil
-	if !configHasCert || certFile != "" || keyFile != "" {
-		var err error
-		config.Certificates = make([]tls.Certificate, 1)
-		config.Certificates[0], err = tls.LoadX509KeyPair(certFile, keyFile)
-		if err != nil {
-			return err
-		}
-	}
-
-	tlsListener := tls.NewListener(l, config)
-	return srv.Serve(tlsListener)
-}
-
-// trackListener adds or removes a net.Listener to the set of tracked
-// listeners.
-//
-// We store a pointer to interface in the map set, in case the
-// net.Listener is not comparable. This is safe because we only call
-// trackListener via Serve and can track+defer untrack the same
-// pointer to local variable there. We never need to compare a
-// Listener from another caller.
-//
-// It reports whether the server is still up (not Shutdown or Closed).
-func (s *Server) trackListener(ln *net.Listener, add bool) bool {
-	s.mu.Lock()
-	defer s.mu.Unlock()
-	if s.listeners == nil {
-		s.listeners = make(map[*net.Listener]struct{})
-	}
-	if add {
-		if s.shuttingDown() {
-			return false
-		}
-		s.listeners[ln] = struct{}{}
-	} else {
-		delete(s.listeners, ln)
-	}
-	return true
-}
-
-func (s *Server) trackConn(c *conn, add bool) {
-	s.mu.Lock()
-	defer s.mu.Unlock()
-	if s.activeConn == nil {
-		s.activeConn = make(map[*conn]struct{})
-	}
-	if add {
-		s.activeConn[c] = struct{}{}
-	} else {
-		delete(s.activeConn, c)
-	}
-}
-
-func (s *Server) idleTimeout() time.Duration {
-	if s.IdleTimeout != 0 {
-		return s.IdleTimeout
-	}
-	return s.ReadTimeout
-}
-
-func (s *Server) readHeaderTimeout() time.Duration {
-	if s.ReadHeaderTimeout != 0 {
-		return s.ReadHeaderTimeout
-	}
-	return s.ReadTimeout
-}
-
-func (s *Server) doKeepAlives() bool {
-	return atomic.LoadInt32(&s.disableKeepAlives) == 0 && !s.shuttingDown()
-}
-
-func (s *Server) shuttingDown() bool {
-	return s.inShutdown.isSet()
-}
-
-// SetKeepAlivesEnabled controls whether HTTP keep-alives are enabled.
-// By default, keep-alives are always enabled. Only very
-// resource-constrained environments or servers in the process of
-// shutting down should disable them.
-func (srv *Server) SetKeepAlivesEnabled(v bool) {
-	if v {
-		atomic.StoreInt32(&srv.disableKeepAlives, 0)
-		return
-	}
-	atomic.StoreInt32(&srv.disableKeepAlives, 1)
-
-	// Close idle HTTP/1 conns:
-	srv.closeIdleConns()
-
-	// TODO: Issue 26303: close HTTP/2 conns as soon as they become idle.
-}
-
-func (s *Server) logf(format string, args ...any) {
-	if s.ErrorLog != nil {
-		s.ErrorLog.Printf(format, args...)
-	} else {
-		log.Printf(format, args...)
-	}
-}
-
-// logf prints to the ErrorLog of the *Server associated with request r
-// via ServerContextKey. If there's no associated server, or if ErrorLog
-// is nil, logging is done via the log package's standard logger.
-func logf(r *Request, format string, args ...any) {
-	s, _ := r.Context().Value(ServerContextKey).(*Server)
-	if s != nil && s.ErrorLog != nil {
-		s.ErrorLog.Printf(format, args...)
-	} else {
-		log.Printf(format, args...)
-	}
-}
-
-// ListenAndServe listens on the TCP network address addr and then calls
-// Serve with handler to handle requests on incoming connections.
-// Accepted connections are configured to enable TCP keep-alives.
-//
-// The handler is typically nil, in which case the DefaultServeMux is used.
-//
-// ListenAndServe always returns a non-nil error.
-func ListenAndServe(addr string, handler Handler) error {
-	server := &Server{Addr: addr, Handler: handler}
-	return server.ListenAndServe()
-}
-
-// ListenAndServeTLS acts identically to ListenAndServe, except that it
-// expects HTTPS connections. Additionally, files containing a certificate and
-// matching private key for the server must be provided. If the certificate
-// is signed by a certificate authority, the certFile should be the concatenation
-// of the server's certificate, any intermediates, and the CA's certificate.
-func ListenAndServeTLS(addr, certFile, keyFile string, handler Handler) error {
-	server := &Server{Addr: addr, Handler: handler}
-	return server.ListenAndServeTLS(certFile, keyFile)
-}
-
-// ListenAndServeTLS listens on the TCP network address srv.Addr and
-// then calls ServeTLS to handle requests on incoming TLS connections.
-// Accepted connections are configured to enable TCP keep-alives.
-//
-// Filenames containing a certificate and matching private key for the
-// server must be provided if neither the Server's TLSConfig.Certificates
-// nor TLSConfig.GetCertificate are populated. If the certificate is
-// signed by a certificate authority, the certFile should be the
-// concatenation of the server's certificate, any intermediates, and
-// the CA's certificate.
-//
-// If srv.Addr is blank, ":https" is used.
-//
-// ListenAndServeTLS always returns a non-nil error. After Shutdown or
-// Close, the returned error is ErrServerClosed.
-func (srv *Server) ListenAndServeTLS(certFile, keyFile string) error {
-	if srv.shuttingDown() {
-		return ErrServerClosed
-	}
-	addr := srv.Addr
-	if addr == "" {
-		addr = ":https"
-	}
-
-	ln, err := net.Listen("tcp", addr)
-	if err != nil {
-		return err
-	}
-
-	defer ln.Close()
-
-	return srv.ServeTLS(ln, certFile, keyFile)
-}
-
-// setupHTTP2_ServeTLS conditionally configures HTTP/2 on
-// srv and reports whether there was an error setting it up. If it is
-// not configured for policy reasons, nil is returned.
-func (srv *Server) setupHTTP2_ServeTLS() error {
-	srv.nextProtoOnce.Do(srv.onceSetNextProtoDefaults)
-	return srv.nextProtoErr
-}
-
-// setupHTTP2_Serve is called from (*Server).Serve and conditionally
-// configures HTTP/2 on srv using a more conservative policy than
-// setupHTTP2_ServeTLS because Serve is called after tls.Listen,
-// and may be called concurrently. See shouldConfigureHTTP2ForServe.
-//
-// The tests named TestTransportAutomaticHTTP2* and
-// TestConcurrentServerServe in server_test.go demonstrate some
-// of the supported use cases and motivations.
-func (srv *Server) setupHTTP2_Serve() error {
-	srv.nextProtoOnce.Do(srv.onceSetNextProtoDefaults_Serve)
-	return srv.nextProtoErr
-}
-
-func (srv *Server) onceSetNextProtoDefaults_Serve() {
-	if srv.shouldConfigureHTTP2ForServe() {
-		srv.onceSetNextProtoDefaults()
-	}
-}
-
-// onceSetNextProtoDefaults configures HTTP/2, if the user hasn't
-// configured otherwise. (by setting srv.TLSNextProto non-nil)
-// It must only be called via srv.nextProtoOnce (use srv.setupHTTP2_*).
-func (srv *Server) onceSetNextProtoDefaults() {
-	if omitBundledHTTP2 || godebug.Get("http2server") == "0" {
-		return
-	}
-	// Enable HTTP/2 by default if the user hasn't otherwise
-	// configured their TLSNextProto map.
-	if srv.TLSNextProto == nil {
-		conf := &http2Server{
-			NewWriteScheduler: func() http2WriteScheduler { return http2NewPriorityWriteScheduler(nil) },
-		}
-		srv.nextProtoErr = http2ConfigureServer(srv, conf)
-	}
-}
-
-// TimeoutHandler returns a Handler that runs h with the given time limit.
-//
-// The new Handler calls h.ServeHTTP to handle each request, but if a
-// call runs for longer than its time limit, the handler responds with
-// a 503 Service Unavailable error and the given message in its body.
-// (If msg is empty, a suitable default message will be sent.)
-// After such a timeout, writes by h to its ResponseWriter will return
-// ErrHandlerTimeout.
-//
-// TimeoutHandler supports the Pusher interface but does not support
-// the Hijacker or Flusher interfaces.
-func TimeoutHandler(h Handler, dt time.Duration, msg string) Handler {
-	return &timeoutHandler{
-		handler: h,
-		body:    msg,
-		dt:      dt,
-	}
-}
-
-// ErrHandlerTimeout is returned on ResponseWriter Write calls
-// in handlers which have timed out.
-var ErrHandlerTimeout = errors.New("http: Handler timeout")
-
-type timeoutHandler struct {
-	handler Handler
-	body    string
-	dt      time.Duration
-
-	// When set, no context will be created and this context will
-	// be used instead.
-	testContext context.Context
-}
-
-func (h *timeoutHandler) errorBody() string {
-	if h.body != "" {
-		return h.body
-	}
-	return "<html><head><title>Timeout</title></head><body><h1>Timeout</h1></body></html>"
-}
-
-func (h *timeoutHandler) ServeHTTP(w ResponseWriter, r *Request) {
-	ctx := h.testContext
-	if ctx == nil {
-		var cancelCtx context.CancelFunc
-		ctx, cancelCtx = context.WithTimeout(r.Context(), h.dt)
-		defer cancelCtx()
-	}
-	r = r.WithContext(ctx)
-	done := make(chan struct{})
-	tw := &timeoutWriter{
-		w:   w,
-		h:   make(Header),
-		req: r,
-	}
-	panicChan := make(chan any, 1)
-	go func() {
-		defer func() {
-			if p := recover(); p != nil {
-				panicChan <- p
-			}
-		}()
-		h.handler.ServeHTTP(tw, r)
-		close(done)
-	}()
-	select {
-	case p := <-panicChan:
-		panic(p)
-	case <-done:
-		tw.mu.Lock()
-		defer tw.mu.Unlock()
-		dst := w.Header()
-		for k, vv := range tw.h {
-			dst[k] = vv
-		}
-		if !tw.wroteHeader {
-			tw.code = StatusOK
-		}
-		w.WriteHeader(tw.code)
-		w.Write(tw.wbuf.Bytes())
-	case <-ctx.Done():
-		tw.mu.Lock()
-		defer tw.mu.Unlock()
-		switch err := ctx.Err(); err {
-		case context.DeadlineExceeded:
-			w.WriteHeader(StatusServiceUnavailable)
-			io.WriteString(w, h.errorBody())
-			tw.err = ErrHandlerTimeout
-		default:
-			w.WriteHeader(StatusServiceUnavailable)
-			tw.err = err
-		}
-	}
-}
-
-type timeoutWriter struct {
-	w    ResponseWriter
-	h    Header
-	wbuf bytes.Buffer
-	req  *Request
-
-	mu          sync.Mutex
-	err         error
-	wroteHeader bool
-	code        int
-}
-
-var _ Pusher = (*timeoutWriter)(nil)
-
-// Push implements the Pusher interface.
-func (tw *timeoutWriter) Push(target string, opts *PushOptions) error {
-	if pusher, ok := tw.w.(Pusher); ok {
-		return pusher.Push(target, opts)
-	}
-	return ErrNotSupported
-}
-
-func (tw *timeoutWriter) Header() Header { return tw.h }
-
-func (tw *timeoutWriter) Write(p []byte) (int, error) {
-	tw.mu.Lock()
-	defer tw.mu.Unlock()
-	if tw.err != nil {
-		return 0, tw.err
-	}
-	if !tw.wroteHeader {
-		tw.writeHeaderLocked(StatusOK)
-	}
-	return tw.wbuf.Write(p)
-}
-
-func (tw *timeoutWriter) writeHeaderLocked(code int) {
-	checkWriteHeaderCode(code)
-
-	switch {
-	case tw.err != nil:
-		return
-	case tw.wroteHeader:
-		if tw.req != nil {
-			caller := relevantCaller()
-			logf(tw.req, "http: superfluous response.WriteHeader call from %s (%s:%d)", caller.Function, path.Base(caller.File), caller.Line)
-		}
-	default:
-		tw.wroteHeader = true
-		tw.code = code
-	}
-}
-
-func (tw *timeoutWriter) WriteHeader(code int) {
-	tw.mu.Lock()
-	defer tw.mu.Unlock()
-	tw.writeHeaderLocked(code)
-}
-
-// onceCloseListener wraps a net.Listener, protecting it from
-// multiple Close calls.
-type onceCloseListener struct {
-	net.Listener
-	once     sync.Once
-	closeErr error
-}
-
-func (oc *onceCloseListener) Close() error {
-	oc.once.Do(oc.close)
-	return oc.closeErr
-}
-
-func (oc *onceCloseListener) close() { oc.closeErr = oc.Listener.Close() }
-
-// globalOptionsHandler responds to "OPTIONS *" requests.
-type globalOptionsHandler struct{}
-
-func (globalOptionsHandler) ServeHTTP(w ResponseWriter, r *Request) {
-	w.Header().Set("Content-Length", "0")
-	if r.ContentLength != 0 {
-		// Read up to 4KB of OPTIONS body (as mentioned in the
-		// spec as being reserved for future use), but anything
-		// over that is considered a waste of server resources
-		// (or an attack) and we abort and close the connection,
-		// courtesy of MaxBytesReader's EOF behavior.
-		mb := MaxBytesReader(w, r.Body, 4<<10)
-		io.Copy(io.Discard, mb)
-	}
-}
-
-// initALPNRequest is an HTTP handler that initializes certain
-// uninitialized fields in its *Request. Such partially-initialized
-// Requests come from ALPN protocol handlers.
-type initALPNRequest struct {
-	ctx context.Context
-	c   *tls.Conn
-	h   serverHandler
-}
-
-// BaseContext is an exported but unadvertised http.Handler method
-// recognized by x/net/http2 to pass down a context; the TLSNextProto
-// API predates context support so we shoehorn through the only
-// interface we have available.
-func (h initALPNRequest) BaseContext() context.Context { return h.ctx }
-
-func (h initALPNRequest) ServeHTTP(rw ResponseWriter, req *Request) {
-	if req.TLS == nil {
-		req.TLS = &tls.ConnectionState{}
-		*req.TLS = h.c.ConnectionState()
-	}
-	if req.Body == nil {
-		req.Body = NoBody
-	}
-	if req.RemoteAddr == "" {
-		req.RemoteAddr = h.c.RemoteAddr().String()
-	}
-	h.h.ServeHTTP(rw, req)
-}
-
-// loggingConn is used for debugging.
-type loggingConn struct {
-	name string
-	net.Conn
-}
-
-var (
-	uniqNameMu   sync.Mutex
-	uniqNameNext = make(map[string]int)
-)
-
-func newLoggingConn(baseName string, c net.Conn) net.Conn {
-	uniqNameMu.Lock()
-	defer uniqNameMu.Unlock()
-	uniqNameNext[baseName]++
-	return &loggingConn{
-		name: fmt.Sprintf("%s-%d", baseName, uniqNameNext[baseName]),
-		Conn: c,
-	}
-}
-
-func (c *loggingConn) Write(p []byte) (n int, err error) {
-	log.Printf("%s.Write(%d) = ....", c.name, len(p))
-	n, err = c.Conn.Write(p)
-	log.Printf("%s.Write(%d) = %d, %v", c.name, len(p), n, err)
-	return
-}
-
-func (c *loggingConn) Read(p []byte) (n int, err error) {
-	log.Printf("%s.Read(%d) = ....", c.name, len(p))
-	n, err = c.Conn.Read(p)
-	log.Printf("%s.Read(%d) = %d, %v", c.name, len(p), n, err)
-	return
-}
-
-func (c *loggingConn) Close() (err error) {
-	log.Printf("%s.Close() = ...", c.name)
-	err = c.Conn.Close()
-	log.Printf("%s.Close() = %v", c.name, err)
-	return
-}
-
-// checkConnErrorWriter writes to c.rwc and records any write errors to c.werr.
-// It only contains one field (and a pointer field at that), so it
-// fits in an interface value without an extra allocation.
-type checkConnErrorWriter struct {
-	c *conn
-}
-
-func (w checkConnErrorWriter) Write(p []byte) (n int, err error) {
-	n, err = w.c.rwc.Write(p)
-	if err != nil && w.c.werr == nil {
-		w.c.werr = err
-		w.c.cancelCtx()
-	}
-	return
-}
-
-func numLeadingCRorLF(v []byte) (n int) {
-	for _, b := range v {
-		if b == '\r' || b == '\n' {
-			n++
-			continue
-		}
-		break
-	}
-	return
-
-}
-
-func strSliceContains(ss []string, s string) bool {
-	for _, v := range ss {
-		if v == s {
-			return true
-		}
-	}
-	return false
-}
-
-// tlsRecordHeaderLooksLikeHTTP reports whether a TLS record header
-// looks like it might've been a misdirected plaintext HTTP request.
-func tlsRecordHeaderLooksLikeHTTP(hdr [5]byte) bool {
-	switch string(hdr[:]) {
-	case "GET /", "HEAD ", "POST ", "PUT /", "OPTIO":
-		return true
-	}
-	return false
-}
-
-// MaxBytesHandler returns a Handler that runs h with its ResponseWriter and Request.Body wrapped by a MaxBytesReader.
-func MaxBytesHandler(h Handler, n int64) Handler {
-	return HandlerFunc(func(w ResponseWriter, r *Request) {
-		r2 := *r
-		r2.Body = MaxBytesReader(w, r.Body, n)
-		h.ServeHTTP(w, &r2)
-	})
-}
diff --git a/contrib/go/_std_1.18/src/net/http/sniff.go b/contrib/go/_std_1.18/src/net/http/sniff.go
deleted file mode 100644
index 67a7151b0c..0000000000
--- a/contrib/go/_std_1.18/src/net/http/sniff.go
+++ /dev/null
@@ -1,309 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package http
-
-import (
-	"bytes"
-	"encoding/binary"
-)
-
-// The algorithm uses at most sniffLen bytes to make its decision.
-const sniffLen = 512
-
-// DetectContentType implements the algorithm described
-// at https://mimesniff.spec.whatwg.org/ to determine the
-// Content-Type of the given data. It considers at most the
-// first 512 bytes of data. DetectContentType always returns
-// a valid MIME type: if it cannot determine a more specific one, it
-// returns "application/octet-stream".
-func DetectContentType(data []byte) string {
-	if len(data) > sniffLen {
-		data = data[:sniffLen]
-	}
-
-	// Index of the first non-whitespace byte in data.
-	firstNonWS := 0
-	for ; firstNonWS < len(data) && isWS(data[firstNonWS]); firstNonWS++ {
-	}
-
-	for _, sig := range sniffSignatures {
-		if ct := sig.match(data, firstNonWS); ct != "" {
-			return ct
-		}
-	}
-
-	return "application/octet-stream" // fallback
-}
-
-// isWS reports whether the provided byte is a whitespace byte (0xWS)
-// as defined in https://mimesniff.spec.whatwg.org/#terminology.
-func isWS(b byte) bool {
-	switch b {
-	case '\t', '\n', '\x0c', '\r', ' ':
-		return true
-	}
-	return false
-}
-
-// isTT reports whether the provided byte is a tag-terminating byte (0xTT)
-// as defined in https://mimesniff.spec.whatwg.org/#terminology.
-func isTT(b byte) bool {
-	switch b {
-	case ' ', '>':
-		return true
-	}
-	return false
-}
-
-type sniffSig interface {
-	// match returns the MIME type of the data, or "" if unknown.
-	match(data []byte, firstNonWS int) string
-}
-
-// Data matching the table in section 6.
-var sniffSignatures = []sniffSig{
-	htmlSig("<!DOCTYPE HTML"),
-	htmlSig("<HTML"),
-	htmlSig("<HEAD"),
-	htmlSig("<SCRIPT"),
-	htmlSig("<IFRAME"),
-	htmlSig("<H1"),
-	htmlSig("<DIV"),
-	htmlSig("<FONT"),
-	htmlSig("<TABLE"),
-	htmlSig("<A"),
-	htmlSig("<STYLE"),
-	htmlSig("<TITLE"),
-	htmlSig("<B"),
-	htmlSig("<BODY"),
-	htmlSig("<BR"),
-	htmlSig("<P"),
-	htmlSig("<!--"),
-	&maskedSig{
-		mask:   []byte("\xFF\xFF\xFF\xFF\xFF"),
-		pat:    []byte("<?xml"),
-		skipWS: true,
-		ct:     "text/xml; charset=utf-8"},
-	&exactSig{[]byte("%PDF-"), "application/pdf"},
-	&exactSig{[]byte("%!PS-Adobe-"), "application/postscript"},
-
-	// UTF BOMs.
-	&maskedSig{
-		mask: []byte("\xFF\xFF\x00\x00"),
-		pat:  []byte("\xFE\xFF\x00\x00"),
-		ct:   "text/plain; charset=utf-16be",
-	},
-	&maskedSig{
-		mask: []byte("\xFF\xFF\x00\x00"),
-		pat:  []byte("\xFF\xFE\x00\x00"),
-		ct:   "text/plain; charset=utf-16le",
-	},
-	&maskedSig{
-		mask: []byte("\xFF\xFF\xFF\x00"),
-		pat:  []byte("\xEF\xBB\xBF\x00"),
-		ct:   "text/plain; charset=utf-8",
-	},
-
-	// Image types
-	// For posterity, we originally returned "image/vnd.microsoft.icon" from
-	// https://tools.ietf.org/html/draft-ietf-websec-mime-sniff-03#section-7
-	// https://codereview.appspot.com/4746042
-	// but that has since been replaced with "image/x-icon" in Section 6.2
-	// of https://mimesniff.spec.whatwg.org/#matching-an-image-type-pattern
-	&exactSig{[]byte("\x00\x00\x01\x00"), "image/x-icon"},
-	&exactSig{[]byte("\x00\x00\x02\x00"), "image/x-icon"},
-	&exactSig{[]byte("BM"), "image/bmp"},
-	&exactSig{[]byte("GIF87a"), "image/gif"},
-	&exactSig{[]byte("GIF89a"), "image/gif"},
-	&maskedSig{
-		mask: []byte("\xFF\xFF\xFF\xFF\x00\x00\x00\x00\xFF\xFF\xFF\xFF\xFF\xFF"),
-		pat:  []byte("RIFF\x00\x00\x00\x00WEBPVP"),
-		ct:   "image/webp",
-	},
-	&exactSig{[]byte("\x89PNG\x0D\x0A\x1A\x0A"), "image/png"},
-	&exactSig{[]byte("\xFF\xD8\xFF"), "image/jpeg"},
-
-	// Audio and Video types
-	// Enforce the pattern match ordering as prescribed in
-	// https://mimesniff.spec.whatwg.org/#matching-an-audio-or-video-type-pattern
-	&maskedSig{
-		mask: []byte("\xFF\xFF\xFF\xFF"),
-		pat:  []byte(".snd"),
-		ct:   "audio/basic",
-	},
-	&maskedSig{
-		mask: []byte("\xFF\xFF\xFF\xFF\x00\x00\x00\x00\xFF\xFF\xFF\xFF"),
-		pat:  []byte("FORM\x00\x00\x00\x00AIFF"),
-		ct:   "audio/aiff",
-	},
-	&maskedSig{
-		mask: []byte("\xFF\xFF\xFF"),
-		pat:  []byte("ID3"),
-		ct:   "audio/mpeg",
-	},
-	&maskedSig{
-		mask: []byte("\xFF\xFF\xFF\xFF\xFF"),
-		pat:  []byte("OggS\x00"),
-		ct:   "application/ogg",
-	},
-	&maskedSig{
-		mask: []byte("\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF"),
-		pat:  []byte("MThd\x00\x00\x00\x06"),
-		ct:   "audio/midi",
-	},
-	&maskedSig{
-		mask: []byte("\xFF\xFF\xFF\xFF\x00\x00\x00\x00\xFF\xFF\xFF\xFF"),
-		pat:  []byte("RIFF\x00\x00\x00\x00AVI "),
-		ct:   "video/avi",
-	},
-	&maskedSig{
-		mask: []byte("\xFF\xFF\xFF\xFF\x00\x00\x00\x00\xFF\xFF\xFF\xFF"),
-		pat:  []byte("RIFF\x00\x00\x00\x00WAVE"),
-		ct:   "audio/wave",
-	},
-	// 6.2.0.2. video/mp4
-	mp4Sig{},
-	// 6.2.0.3. video/webm
-	&exactSig{[]byte("\x1A\x45\xDF\xA3"), "video/webm"},
-
-	// Font types
-	&maskedSig{
-		// 34 NULL bytes followed by the string "LP"
-		pat: []byte("\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00LP"),
-		// 34 NULL bytes followed by \xF\xF
-		mask: []byte("\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xFF\xFF"),
-		ct:   "application/vnd.ms-fontobject",
-	},
-	&exactSig{[]byte("\x00\x01\x00\x00"), "font/ttf"},
-	&exactSig{[]byte("OTTO"), "font/otf"},
-	&exactSig{[]byte("ttcf"), "font/collection"},
-	&exactSig{[]byte("wOFF"), "font/woff"},
-	&exactSig{[]byte("wOF2"), "font/woff2"},
-
-	// Archive types
-	&exactSig{[]byte("\x1F\x8B\x08"), "application/x-gzip"},
-	&exactSig{[]byte("PK\x03\x04"), "application/zip"},
-	// RAR's signatures are incorrectly defined by the MIME spec as per
-	//    https://github.com/whatwg/mimesniff/issues/63
-	// However, RAR Labs correctly defines it at:
-	//    https://www.rarlab.com/technote.htm#rarsign
-	// so we use the definition from RAR Labs.
-	// TODO: do whatever the spec ends up doing.
-	&exactSig{[]byte("Rar!\x1A\x07\x00"), "application/x-rar-compressed"},     // RAR v1.5-v4.0
-	&exactSig{[]byte("Rar!\x1A\x07\x01\x00"), "application/x-rar-compressed"}, // RAR v5+
-
-	&exactSig{[]byte("\x00\x61\x73\x6D"), "application/wasm"},
-
-	textSig{}, // should be last
-}
-
-type exactSig struct {
-	sig []byte
-	ct  string
-}
-
-func (e *exactSig) match(data []byte, firstNonWS int) string {
-	if bytes.HasPrefix(data, e.sig) {
-		return e.ct
-	}
-	return ""
-}
-
-type maskedSig struct {
-	mask, pat []byte
-	skipWS    bool
-	ct        string
-}
-
-func (m *maskedSig) match(data []byte, firstNonWS int) string {
-	// pattern matching algorithm section 6
-	// https://mimesniff.spec.whatwg.org/#pattern-matching-algorithm
-
-	if m.skipWS {
-		data = data[firstNonWS:]
-	}
-	if len(m.pat) != len(m.mask) {
-		return ""
-	}
-	if len(data) < len(m.pat) {
-		return ""
-	}
-	for i, pb := range m.pat {
-		maskedData := data[i] & m.mask[i]
-		if maskedData != pb {
-			return ""
-		}
-	}
-	return m.ct
-}
-
-type htmlSig []byte
-
-func (h htmlSig) match(data []byte, firstNonWS int) string {
-	data = data[firstNonWS:]
-	if len(data) < len(h)+1 {
-		return ""
-	}
-	for i, b := range h {
-		db := data[i]
-		if 'A' <= b && b <= 'Z' {
-			db &= 0xDF
-		}
-		if b != db {
-			return ""
-		}
-	}
-	// Next byte must be a tag-terminating byte(0xTT).
-	if !isTT(data[len(h)]) {
-		return ""
-	}
-	return "text/html; charset=utf-8"
-}
-
-var mp4ftype = []byte("ftyp")
-var mp4 = []byte("mp4")
-
-type mp4Sig struct{}
-
-func (mp4Sig) match(data []byte, firstNonWS int) string {
-	// https://mimesniff.spec.whatwg.org/#signature-for-mp4
-	// c.f. section 6.2.1
-	if len(data) < 12 {
-		return ""
-	}
-	boxSize := int(binary.BigEndian.Uint32(data[:4]))
-	if len(data) < boxSize || boxSize%4 != 0 {
-		return ""
-	}
-	if !bytes.Equal(data[4:8], mp4ftype) {
-		return ""
-	}
-	for st := 8; st < boxSize; st += 4 {
-		if st == 12 {
-			// Ignores the four bytes that correspond to the version number of the "major brand".
-			continue
-		}
-		if bytes.Equal(data[st:st+3], mp4) {
-			return "video/mp4"
-		}
-	}
-	return ""
-}
-
-type textSig struct{}
-
-func (textSig) match(data []byte, firstNonWS int) string {
-	// c.f. section 5, step 4.
-	for _, b := range data[firstNonWS:] {
-		switch {
-		case b <= 0x08,
-			b == 0x0B,
-			0x0E <= b && b <= 0x1A,
-			0x1C <= b && b <= 0x1F:
-			return ""
-		}
-	}
-	return "text/plain; charset=utf-8"
-}
diff --git a/contrib/go/_std_1.18/src/net/http/status.go b/contrib/go/_std_1.18/src/net/http/status.go
deleted file mode 100644
index 286315f639..0000000000
--- a/contrib/go/_std_1.18/src/net/http/status.go
+++ /dev/null
@@ -1,152 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package http
-
-// HTTP status codes as registered with IANA.
-// See: https://www.iana.org/assignments/http-status-codes/http-status-codes.xhtml
-const (
-	StatusContinue           = 100 // RFC 7231, 6.2.1
-	StatusSwitchingProtocols = 101 // RFC 7231, 6.2.2
-	StatusProcessing         = 102 // RFC 2518, 10.1
-	StatusEarlyHints         = 103 // RFC 8297
-
-	StatusOK                   = 200 // RFC 7231, 6.3.1
-	StatusCreated              = 201 // RFC 7231, 6.3.2
-	StatusAccepted             = 202 // RFC 7231, 6.3.3
-	StatusNonAuthoritativeInfo = 203 // RFC 7231, 6.3.4
-	StatusNoContent            = 204 // RFC 7231, 6.3.5
-	StatusResetContent         = 205 // RFC 7231, 6.3.6
-	StatusPartialContent       = 206 // RFC 7233, 4.1
-	StatusMultiStatus          = 207 // RFC 4918, 11.1
-	StatusAlreadyReported      = 208 // RFC 5842, 7.1
-	StatusIMUsed               = 226 // RFC 3229, 10.4.1
-
-	StatusMultipleChoices   = 300 // RFC 7231, 6.4.1
-	StatusMovedPermanently  = 301 // RFC 7231, 6.4.2
-	StatusFound             = 302 // RFC 7231, 6.4.3
-	StatusSeeOther          = 303 // RFC 7231, 6.4.4
-	StatusNotModified       = 304 // RFC 7232, 4.1
-	StatusUseProxy          = 305 // RFC 7231, 6.4.5
-	_                       = 306 // RFC 7231, 6.4.6 (Unused)
-	StatusTemporaryRedirect = 307 // RFC 7231, 6.4.7
-	StatusPermanentRedirect = 308 // RFC 7538, 3
-
-	StatusBadRequest                   = 400 // RFC 7231, 6.5.1
-	StatusUnauthorized                 = 401 // RFC 7235, 3.1
-	StatusPaymentRequired              = 402 // RFC 7231, 6.5.2
-	StatusForbidden                    = 403 // RFC 7231, 6.5.3
-	StatusNotFound                     = 404 // RFC 7231, 6.5.4
-	StatusMethodNotAllowed             = 405 // RFC 7231, 6.5.5
-	StatusNotAcceptable                = 406 // RFC 7231, 6.5.6
-	StatusProxyAuthRequired            = 407 // RFC 7235, 3.2
-	StatusRequestTimeout               = 408 // RFC 7231, 6.5.7
-	StatusConflict                     = 409 // RFC 7231, 6.5.8
-	StatusGone                         = 410 // RFC 7231, 6.5.9
-	StatusLengthRequired               = 411 // RFC 7231, 6.5.10
-	StatusPreconditionFailed           = 412 // RFC 7232, 4.2
-	StatusRequestEntityTooLarge        = 413 // RFC 7231, 6.5.11
-	StatusRequestURITooLong            = 414 // RFC 7231, 6.5.12
-	StatusUnsupportedMediaType         = 415 // RFC 7231, 6.5.13
-	StatusRequestedRangeNotSatisfiable = 416 // RFC 7233, 4.4
-	StatusExpectationFailed            = 417 // RFC 7231, 6.5.14
-	StatusTeapot                       = 418 // RFC 7168, 2.3.3
-	StatusMisdirectedRequest           = 421 // RFC 7540, 9.1.2
-	StatusUnprocessableEntity          = 422 // RFC 4918, 11.2
-	StatusLocked                       = 423 // RFC 4918, 11.3
-	StatusFailedDependency             = 424 // RFC 4918, 11.4
-	StatusTooEarly                     = 425 // RFC 8470, 5.2.
-	StatusUpgradeRequired              = 426 // RFC 7231, 6.5.15
-	StatusPreconditionRequired         = 428 // RFC 6585, 3
-	StatusTooManyRequests              = 429 // RFC 6585, 4
-	StatusRequestHeaderFieldsTooLarge  = 431 // RFC 6585, 5
-	StatusUnavailableForLegalReasons   = 451 // RFC 7725, 3
-
-	StatusInternalServerError           = 500 // RFC 7231, 6.6.1
-	StatusNotImplemented                = 501 // RFC 7231, 6.6.2
-	StatusBadGateway                    = 502 // RFC 7231, 6.6.3
-	StatusServiceUnavailable            = 503 // RFC 7231, 6.6.4
-	StatusGatewayTimeout                = 504 // RFC 7231, 6.6.5
-	StatusHTTPVersionNotSupported       = 505 // RFC 7231, 6.6.6
-	StatusVariantAlsoNegotiates         = 506 // RFC 2295, 8.1
-	StatusInsufficientStorage           = 507 // RFC 4918, 11.5
-	StatusLoopDetected                  = 508 // RFC 5842, 7.2
-	StatusNotExtended                   = 510 // RFC 2774, 7
-	StatusNetworkAuthenticationRequired = 511 // RFC 6585, 6
-)
-
-var statusText = map[int]string{
-	StatusContinue:           "Continue",
-	StatusSwitchingProtocols: "Switching Protocols",
-	StatusProcessing:         "Processing",
-	StatusEarlyHints:         "Early Hints",
-
-	StatusOK:                   "OK",
-	StatusCreated:              "Created",
-	StatusAccepted:             "Accepted",
-	StatusNonAuthoritativeInfo: "Non-Authoritative Information",
-	StatusNoContent:            "No Content",
-	StatusResetContent:         "Reset Content",
-	StatusPartialContent:       "Partial Content",
-	StatusMultiStatus:          "Multi-Status",
-	StatusAlreadyReported:      "Already Reported",
-	StatusIMUsed:               "IM Used",
-
-	StatusMultipleChoices:   "Multiple Choices",
-	StatusMovedPermanently:  "Moved Permanently",
-	StatusFound:             "Found",
-	StatusSeeOther:          "See Other",
-	StatusNotModified:       "Not Modified",
-	StatusUseProxy:          "Use Proxy",
-	StatusTemporaryRedirect: "Temporary Redirect",
-	StatusPermanentRedirect: "Permanent Redirect",
-
-	StatusBadRequest:                   "Bad Request",
-	StatusUnauthorized:                 "Unauthorized",
-	StatusPaymentRequired:              "Payment Required",
-	StatusForbidden:                    "Forbidden",
-	StatusNotFound:                     "Not Found",
-	StatusMethodNotAllowed:             "Method Not Allowed",
-	StatusNotAcceptable:                "Not Acceptable",
-	StatusProxyAuthRequired:            "Proxy Authentication Required",
-	StatusRequestTimeout:               "Request Timeout",
-	StatusConflict:                     "Conflict",
-	StatusGone:                         "Gone",
-	StatusLengthRequired:               "Length Required",
-	StatusPreconditionFailed:           "Precondition Failed",
-	StatusRequestEntityTooLarge:        "Request Entity Too Large",
-	StatusRequestURITooLong:            "Request URI Too Long",
-	StatusUnsupportedMediaType:         "Unsupported Media Type",
-	StatusRequestedRangeNotSatisfiable: "Requested Range Not Satisfiable",
-	StatusExpectationFailed:            "Expectation Failed",
-	StatusTeapot:                       "I'm a teapot",
-	StatusMisdirectedRequest:           "Misdirected Request",
-	StatusUnprocessableEntity:          "Unprocessable Entity",
-	StatusLocked:                       "Locked",
-	StatusFailedDependency:             "Failed Dependency",
-	StatusTooEarly:                     "Too Early",
-	StatusUpgradeRequired:              "Upgrade Required",
-	StatusPreconditionRequired:         "Precondition Required",
-	StatusTooManyRequests:              "Too Many Requests",
-	StatusRequestHeaderFieldsTooLarge:  "Request Header Fields Too Large",
-	StatusUnavailableForLegalReasons:   "Unavailable For Legal Reasons",
-
-	StatusInternalServerError:           "Internal Server Error",
-	StatusNotImplemented:                "Not Implemented",
-	StatusBadGateway:                    "Bad Gateway",
-	StatusServiceUnavailable:            "Service Unavailable",
-	StatusGatewayTimeout:                "Gateway Timeout",
-	StatusHTTPVersionNotSupported:       "HTTP Version Not Supported",
-	StatusVariantAlsoNegotiates:         "Variant Also Negotiates",
-	StatusInsufficientStorage:           "Insufficient Storage",
-	StatusLoopDetected:                  "Loop Detected",
-	StatusNotExtended:                   "Not Extended",
-	StatusNetworkAuthenticationRequired: "Network Authentication Required",
-}
-
-// StatusText returns a text for the HTTP status code. It returns the empty
-// string if the code is unknown.
-func StatusText(code int) string {
-	return statusText[code]
-}
diff --git a/contrib/go/_std_1.18/src/net/http/transfer.go b/contrib/go/_std_1.18/src/net/http/transfer.go
deleted file mode 100644
index de69d835ac..0000000000
--- a/contrib/go/_std_1.18/src/net/http/transfer.go
+++ /dev/null
@@ -1,1114 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package http
-
-import (
-	"bufio"
-	"bytes"
-	"errors"
-	"fmt"
-	"io"
-	"net/http/httptrace"
-	"net/http/internal"
-	"net/http/internal/ascii"
-	"net/textproto"
-	"reflect"
-	"sort"
-	"strconv"
-	"strings"
-	"sync"
-	"time"
-
-	"golang.org/x/net/http/httpguts"
-)
-
-// ErrLineTooLong is returned when reading request or response bodies
-// with malformed chunked encoding.
-var ErrLineTooLong = internal.ErrLineTooLong
-
-type errorReader struct {
-	err error
-}
-
-func (r errorReader) Read(p []byte) (n int, err error) {
-	return 0, r.err
-}
-
-type byteReader struct {
-	b    byte
-	done bool
-}
-
-func (br *byteReader) Read(p []byte) (n int, err error) {
-	if br.done {
-		return 0, io.EOF
-	}
-	if len(p) == 0 {
-		return 0, nil
-	}
-	br.done = true
-	p[0] = br.b
-	return 1, io.EOF
-}
-
-// transferWriter inspects the fields of a user-supplied Request or Response,
-// sanitizes them without changing the user object and provides methods for
-// writing the respective header, body and trailer in wire format.
-type transferWriter struct {
-	Method           string
-	Body             io.Reader
-	BodyCloser       io.Closer
-	ResponseToHEAD   bool
-	ContentLength    int64 // -1 means unknown, 0 means exactly none
-	Close            bool
-	TransferEncoding []string
-	Header           Header
-	Trailer          Header
-	IsResponse       bool
-	bodyReadError    error // any non-EOF error from reading Body
-
-	FlushHeaders bool            // flush headers to network before body
-	ByteReadCh   chan readResult // non-nil if probeRequestBody called
-}
-
-func newTransferWriter(r any) (t *transferWriter, err error) {
-	t = &transferWriter{}
-
-	// Extract relevant fields
-	atLeastHTTP11 := false
-	switch rr := r.(type) {
-	case *Request:
-		if rr.ContentLength != 0 && rr.Body == nil {
-			return nil, fmt.Errorf("http: Request.ContentLength=%d with nil Body", rr.ContentLength)
-		}
-		t.Method = valueOrDefault(rr.Method, "GET")
-		t.Close = rr.Close
-		t.TransferEncoding = rr.TransferEncoding
-		t.Header = rr.Header
-		t.Trailer = rr.Trailer
-		t.Body = rr.Body
-		t.BodyCloser = rr.Body
-		t.ContentLength = rr.outgoingLength()
-		if t.ContentLength < 0 && len(t.TransferEncoding) == 0 && t.shouldSendChunkedRequestBody() {
-			t.TransferEncoding = []string{"chunked"}
-		}
-		// If there's a body, conservatively flush the headers
-		// to any bufio.Writer we're writing to, just in case
-		// the server needs the headers early, before we copy
-		// the body and possibly block. We make an exception
-		// for the common standard library in-memory types,
-		// though, to avoid unnecessary TCP packets on the
-		// wire. (Issue 22088.)
-		if t.ContentLength != 0 && !isKnownInMemoryReader(t.Body) {
-			t.FlushHeaders = true
-		}
-
-		atLeastHTTP11 = true // Transport requests are always 1.1 or 2.0
-	case *Response:
-		t.IsResponse = true
-		if rr.Request != nil {
-			t.Method = rr.Request.Method
-		}
-		t.Body = rr.Body
-		t.BodyCloser = rr.Body
-		t.ContentLength = rr.ContentLength
-		t.Close = rr.Close
-		t.TransferEncoding = rr.TransferEncoding
-		t.Header = rr.Header
-		t.Trailer = rr.Trailer
-		atLeastHTTP11 = rr.ProtoAtLeast(1, 1)
-		t.ResponseToHEAD = noResponseBodyExpected(t.Method)
-	}
-
-	// Sanitize Body,ContentLength,TransferEncoding
-	if t.ResponseToHEAD {
-		t.Body = nil
-		if chunked(t.TransferEncoding) {
-			t.ContentLength = -1
-		}
-	} else {
-		if !atLeastHTTP11 || t.Body == nil {
-			t.TransferEncoding = nil
-		}
-		if chunked(t.TransferEncoding) {
-			t.ContentLength = -1
-		} else if t.Body == nil { // no chunking, no body
-			t.ContentLength = 0
-		}
-	}
-
-	// Sanitize Trailer
-	if !chunked(t.TransferEncoding) {
-		t.Trailer = nil
-	}
-
-	return t, nil
-}
-
-// shouldSendChunkedRequestBody reports whether we should try to send a
-// chunked request body to the server. In particular, the case we really
-// want to prevent is sending a GET or other typically-bodyless request to a
-// server with a chunked body when the body has zero bytes, since GETs with
-// bodies (while acceptable according to specs), even zero-byte chunked
-// bodies, are approximately never seen in the wild and confuse most
-// servers. See Issue 18257, as one example.
-//
-// The only reason we'd send such a request is if the user set the Body to a
-// non-nil value (say, io.NopCloser(bytes.NewReader(nil))) and didn't
-// set ContentLength, or NewRequest set it to -1 (unknown), so then we assume
-// there's bytes to send.
-//
-// This code tries to read a byte from the Request.Body in such cases to see
-// whether the body actually has content (super rare) or is actually just
-// a non-nil content-less ReadCloser (the more common case). In that more
-// common case, we act as if their Body were nil instead, and don't send
-// a body.
-func (t *transferWriter) shouldSendChunkedRequestBody() bool {
-	// Note that t.ContentLength is the corrected content length
-	// from rr.outgoingLength, so 0 actually means zero, not unknown.
-	if t.ContentLength >= 0 || t.Body == nil { // redundant checks; caller did them
-		return false
-	}
-	if t.Method == "CONNECT" {
-		return false
-	}
-	if requestMethodUsuallyLacksBody(t.Method) {
-		// Only probe the Request.Body for GET/HEAD/DELETE/etc
-		// requests, because it's only those types of requests
-		// that confuse servers.
-		t.probeRequestBody() // adjusts t.Body, t.ContentLength
-		return t.Body != nil
-	}
-	// For all other request types (PUT, POST, PATCH, or anything
-	// made-up we've never heard of), assume it's normal and the server
-	// can deal with a chunked request body. Maybe we'll adjust this
-	// later.
-	return true
-}
-
-// probeRequestBody reads a byte from t.Body to see whether it's empty
-// (returns io.EOF right away).
-//
-// But because we've had problems with this blocking users in the past
-// (issue 17480) when the body is a pipe (perhaps waiting on the response
-// headers before the pipe is fed data), we need to be careful and bound how
-// long we wait for it. This delay will only affect users if all the following
-// are true:
-//   * the request body blocks
-//   * the content length is not set (or set to -1)
-//   * the method doesn't usually have a body (GET, HEAD, DELETE, ...)
-//   * there is no transfer-encoding=chunked already set.
-// In other words, this delay will not normally affect anybody, and there
-// are workarounds if it does.
-func (t *transferWriter) probeRequestBody() {
-	t.ByteReadCh = make(chan readResult, 1)
-	go func(body io.Reader) {
-		var buf [1]byte
-		var rres readResult
-		rres.n, rres.err = body.Read(buf[:])
-		if rres.n == 1 {
-			rres.b = buf[0]
-		}
-		t.ByteReadCh <- rres
-		close(t.ByteReadCh)
-	}(t.Body)
-	timer := time.NewTimer(200 * time.Millisecond)
-	select {
-	case rres := <-t.ByteReadCh:
-		timer.Stop()
-		if rres.n == 0 && rres.err == io.EOF {
-			// It was empty.
-			t.Body = nil
-			t.ContentLength = 0
-		} else if rres.n == 1 {
-			if rres.err != nil {
-				t.Body = io.MultiReader(&byteReader{b: rres.b}, errorReader{rres.err})
-			} else {
-				t.Body = io.MultiReader(&byteReader{b: rres.b}, t.Body)
-			}
-		} else if rres.err != nil {
-			t.Body = errorReader{rres.err}
-		}
-	case <-timer.C:
-		// Too slow. Don't wait. Read it later, and keep
-		// assuming that this is ContentLength == -1
-		// (unknown), which means we'll send a
-		// "Transfer-Encoding: chunked" header.
-		t.Body = io.MultiReader(finishAsyncByteRead{t}, t.Body)
-		// Request that Request.Write flush the headers to the
-		// network before writing the body, since our body may not
-		// become readable until it's seen the response headers.
-		t.FlushHeaders = true
-	}
-}
-
-func noResponseBodyExpected(requestMethod string) bool {
-	return requestMethod == "HEAD"
-}
-
-func (t *transferWriter) shouldSendContentLength() bool {
-	if chunked(t.TransferEncoding) {
-		return false
-	}
-	if t.ContentLength > 0 {
-		return true
-	}
-	if t.ContentLength < 0 {
-		return false
-	}
-	// Many servers expect a Content-Length for these methods
-	if t.Method == "POST" || t.Method == "PUT" || t.Method == "PATCH" {
-		return true
-	}
-	if t.ContentLength == 0 && isIdentity(t.TransferEncoding) {
-		if t.Method == "GET" || t.Method == "HEAD" {
-			return false
-		}
-		return true
-	}
-
-	return false
-}
-
-func (t *transferWriter) writeHeader(w io.Writer, trace *httptrace.ClientTrace) error {
-	if t.Close && !hasToken(t.Header.get("Connection"), "close") {
-		if _, err := io.WriteString(w, "Connection: close\r\n"); err != nil {
-			return err
-		}
-		if trace != nil && trace.WroteHeaderField != nil {
-			trace.WroteHeaderField("Connection", []string{"close"})
-		}
-	}
-
-	// Write Content-Length and/or Transfer-Encoding whose values are a
-	// function of the sanitized field triple (Body, ContentLength,
-	// TransferEncoding)
-	if t.shouldSendContentLength() {
-		if _, err := io.WriteString(w, "Content-Length: "); err != nil {
-			return err
-		}
-		if _, err := io.WriteString(w, strconv.FormatInt(t.ContentLength, 10)+"\r\n"); err != nil {
-			return err
-		}
-		if trace != nil && trace.WroteHeaderField != nil {
-			trace.WroteHeaderField("Content-Length", []string{strconv.FormatInt(t.ContentLength, 10)})
-		}
-	} else if chunked(t.TransferEncoding) {
-		if _, err := io.WriteString(w, "Transfer-Encoding: chunked\r\n"); err != nil {
-			return err
-		}
-		if trace != nil && trace.WroteHeaderField != nil {
-			trace.WroteHeaderField("Transfer-Encoding", []string{"chunked"})
-		}
-	}
-
-	// Write Trailer header
-	if t.Trailer != nil {
-		keys := make([]string, 0, len(t.Trailer))
-		for k := range t.Trailer {
-			k = CanonicalHeaderKey(k)
-			switch k {
-			case "Transfer-Encoding", "Trailer", "Content-Length":
-				return badStringError("invalid Trailer key", k)
-			}
-			keys = append(keys, k)
-		}
-		if len(keys) > 0 {
-			sort.Strings(keys)
-			// TODO: could do better allocation-wise here, but trailers are rare,
-			// so being lazy for now.
-			if _, err := io.WriteString(w, "Trailer: "+strings.Join(keys, ",")+"\r\n"); err != nil {
-				return err
-			}
-			if trace != nil && trace.WroteHeaderField != nil {
-				trace.WroteHeaderField("Trailer", keys)
-			}
-		}
-	}
-
-	return nil
-}
-
-// always closes t.BodyCloser
-func (t *transferWriter) writeBody(w io.Writer) (err error) {
-	var ncopy int64
-	closed := false
-	defer func() {
-		if closed || t.BodyCloser == nil {
-			return
-		}
-		if closeErr := t.BodyCloser.Close(); closeErr != nil && err == nil {
-			err = closeErr
-		}
-	}()
-
-	// Write body. We "unwrap" the body first if it was wrapped in a
-	// nopCloser or readTrackingBody. This is to ensure that we can take advantage of
-	// OS-level optimizations in the event that the body is an
-	// *os.File.
-	if t.Body != nil {
-		var body = t.unwrapBody()
-		if chunked(t.TransferEncoding) {
-			if bw, ok := w.(*bufio.Writer); ok && !t.IsResponse {
-				w = &internal.FlushAfterChunkWriter{Writer: bw}
-			}
-			cw := internal.NewChunkedWriter(w)
-			_, err = t.doBodyCopy(cw, body)
-			if err == nil {
-				err = cw.Close()
-			}
-		} else if t.ContentLength == -1 {
-			dst := w
-			if t.Method == "CONNECT" {
-				dst = bufioFlushWriter{dst}
-			}
-			ncopy, err = t.doBodyCopy(dst, body)
-		} else {
-			ncopy, err = t.doBodyCopy(w, io.LimitReader(body, t.ContentLength))
-			if err != nil {
-				return err
-			}
-			var nextra int64
-			nextra, err = t.doBodyCopy(io.Discard, body)
-			ncopy += nextra
-		}
-		if err != nil {
-			return err
-		}
-	}
-	if t.BodyCloser != nil {
-		closed = true
-		if err := t.BodyCloser.Close(); err != nil {
-			return err
-		}
-	}
-
-	if !t.ResponseToHEAD && t.ContentLength != -1 && t.ContentLength != ncopy {
-		return fmt.Errorf("http: ContentLength=%d with Body length %d",
-			t.ContentLength, ncopy)
-	}
-
-	if chunked(t.TransferEncoding) {
-		// Write Trailer header
-		if t.Trailer != nil {
-			if err := t.Trailer.Write(w); err != nil {
-				return err
-			}
-		}
-		// Last chunk, empty trailer
-		_, err = io.WriteString(w, "\r\n")
-	}
-	return err
-}
-
-// doBodyCopy wraps a copy operation, with any resulting error also
-// being saved in bodyReadError.
-//
-// This function is only intended for use in writeBody.
-func (t *transferWriter) doBodyCopy(dst io.Writer, src io.Reader) (n int64, err error) {
-	n, err = io.Copy(dst, src)
-	if err != nil && err != io.EOF {
-		t.bodyReadError = err
-	}
-	return
-}
-
-// unwrapBodyReader unwraps the body's inner reader if it's a
-// nopCloser. This is to ensure that body writes sourced from local
-// files (*os.File types) are properly optimized.
-//
-// This function is only intended for use in writeBody.
-func (t *transferWriter) unwrapBody() io.Reader {
-	if reflect.TypeOf(t.Body) == nopCloserType {
-		return reflect.ValueOf(t.Body).Field(0).Interface().(io.Reader)
-	}
-	if r, ok := t.Body.(*readTrackingBody); ok {
-		r.didRead = true
-		return r.ReadCloser
-	}
-	return t.Body
-}
-
-type transferReader struct {
-	// Input
-	Header        Header
-	StatusCode    int
-	RequestMethod string
-	ProtoMajor    int
-	ProtoMinor    int
-	// Output
-	Body          io.ReadCloser
-	ContentLength int64
-	Chunked       bool
-	Close         bool
-	Trailer       Header
-}
-
-func (t *transferReader) protoAtLeast(m, n int) bool {
-	return t.ProtoMajor > m || (t.ProtoMajor == m && t.ProtoMinor >= n)
-}
-
-// bodyAllowedForStatus reports whether a given response status code
-// permits a body. See RFC 7230, section 3.3.
-func bodyAllowedForStatus(status int) bool {
-	switch {
-	case status >= 100 && status <= 199:
-		return false
-	case status == 204:
-		return false
-	case status == 304:
-		return false
-	}
-	return true
-}
-
-var (
-	suppressedHeaders304    = []string{"Content-Type", "Content-Length", "Transfer-Encoding"}
-	suppressedHeadersNoBody = []string{"Content-Length", "Transfer-Encoding"}
-)
-
-func suppressedHeaders(status int) []string {
-	switch {
-	case status == 304:
-		// RFC 7232 section 4.1
-		return suppressedHeaders304
-	case !bodyAllowedForStatus(status):
-		return suppressedHeadersNoBody
-	}
-	return nil
-}
-
-// msg is *Request or *Response.
-func readTransfer(msg any, r *bufio.Reader) (err error) {
-	t := &transferReader{RequestMethod: "GET"}
-
-	// Unify input
-	isResponse := false
-	switch rr := msg.(type) {
-	case *Response:
-		t.Header = rr.Header
-		t.StatusCode = rr.StatusCode
-		t.ProtoMajor = rr.ProtoMajor
-		t.ProtoMinor = rr.ProtoMinor
-		t.Close = shouldClose(t.ProtoMajor, t.ProtoMinor, t.Header, true)
-		isResponse = true
-		if rr.Request != nil {
-			t.RequestMethod = rr.Request.Method
-		}
-	case *Request:
-		t.Header = rr.Header
-		t.RequestMethod = rr.Method
-		t.ProtoMajor = rr.ProtoMajor
-		t.ProtoMinor = rr.ProtoMinor
-		// Transfer semantics for Requests are exactly like those for
-		// Responses with status code 200, responding to a GET method
-		t.StatusCode = 200
-		t.Close = rr.Close
-	default:
-		panic("unexpected type")
-	}
-
-	// Default to HTTP/1.1
-	if t.ProtoMajor == 0 && t.ProtoMinor == 0 {
-		t.ProtoMajor, t.ProtoMinor = 1, 1
-	}
-
-	// Transfer-Encoding: chunked, and overriding Content-Length.
-	if err := t.parseTransferEncoding(); err != nil {
-		return err
-	}
-
-	realLength, err := fixLength(isResponse, t.StatusCode, t.RequestMethod, t.Header, t.Chunked)
-	if err != nil {
-		return err
-	}
-	if isResponse && t.RequestMethod == "HEAD" {
-		if n, err := parseContentLength(t.Header.get("Content-Length")); err != nil {
-			return err
-		} else {
-			t.ContentLength = n
-		}
-	} else {
-		t.ContentLength = realLength
-	}
-
-	// Trailer
-	t.Trailer, err = fixTrailer(t.Header, t.Chunked)
-	if err != nil {
-		return err
-	}
-
-	// If there is no Content-Length or chunked Transfer-Encoding on a *Response
-	// and the status is not 1xx, 204 or 304, then the body is unbounded.
-	// See RFC 7230, section 3.3.
-	switch msg.(type) {
-	case *Response:
-		if realLength == -1 && !t.Chunked && bodyAllowedForStatus(t.StatusCode) {
-			// Unbounded body.
-			t.Close = true
-		}
-	}
-
-	// Prepare body reader. ContentLength < 0 means chunked encoding
-	// or close connection when finished, since multipart is not supported yet
-	switch {
-	case t.Chunked:
-		if noResponseBodyExpected(t.RequestMethod) || !bodyAllowedForStatus(t.StatusCode) {
-			t.Body = NoBody
-		} else {
-			t.Body = &body{src: internal.NewChunkedReader(r), hdr: msg, r: r, closing: t.Close}
-		}
-	case realLength == 0:
-		t.Body = NoBody
-	case realLength > 0:
-		t.Body = &body{src: io.LimitReader(r, realLength), closing: t.Close}
-	default:
-		// realLength < 0, i.e. "Content-Length" not mentioned in header
-		if t.Close {
-			// Close semantics (i.e. HTTP/1.0)
-			t.Body = &body{src: r, closing: t.Close}
-		} else {
-			// Persistent connection (i.e. HTTP/1.1)
-			t.Body = NoBody
-		}
-	}
-
-	// Unify output
-	switch rr := msg.(type) {
-	case *Request:
-		rr.Body = t.Body
-		rr.ContentLength = t.ContentLength
-		if t.Chunked {
-			rr.TransferEncoding = []string{"chunked"}
-		}
-		rr.Close = t.Close
-		rr.Trailer = t.Trailer
-	case *Response:
-		rr.Body = t.Body
-		rr.ContentLength = t.ContentLength
-		if t.Chunked {
-			rr.TransferEncoding = []string{"chunked"}
-		}
-		rr.Close = t.Close
-		rr.Trailer = t.Trailer
-	}
-
-	return nil
-}
-
-// Checks whether chunked is part of the encodings stack
-func chunked(te []string) bool { return len(te) > 0 && te[0] == "chunked" }
-
-// Checks whether the encoding is explicitly "identity".
-func isIdentity(te []string) bool { return len(te) == 1 && te[0] == "identity" }
-
-// unsupportedTEError reports unsupported transfer-encodings.
-type unsupportedTEError struct {
-	err string
-}
-
-func (uste *unsupportedTEError) Error() string {
-	return uste.err
-}
-
-// isUnsupportedTEError checks if the error is of type
-// unsupportedTEError. It is usually invoked with a non-nil err.
-func isUnsupportedTEError(err error) bool {
-	_, ok := err.(*unsupportedTEError)
-	return ok
-}
-
-// parseTransferEncoding sets t.Chunked based on the Transfer-Encoding header.
-func (t *transferReader) parseTransferEncoding() error {
-	raw, present := t.Header["Transfer-Encoding"]
-	if !present {
-		return nil
-	}
-	delete(t.Header, "Transfer-Encoding")
-
-	// Issue 12785; ignore Transfer-Encoding on HTTP/1.0 requests.
-	if !t.protoAtLeast(1, 1) {
-		return nil
-	}
-
-	// Like nginx, we only support a single Transfer-Encoding header field, and
-	// only if set to "chunked". This is one of the most security sensitive
-	// surfaces in HTTP/1.1 due to the risk of request smuggling, so we keep it
-	// strict and simple.
-	if len(raw) != 1 {
-		return &unsupportedTEError{fmt.Sprintf("too many transfer encodings: %q", raw)}
-	}
-	if !ascii.EqualFold(raw[0], "chunked") {
-		return &unsupportedTEError{fmt.Sprintf("unsupported transfer encoding: %q", raw[0])}
-	}
-
-	// RFC 7230 3.3.2 says "A sender MUST NOT send a Content-Length header field
-	// in any message that contains a Transfer-Encoding header field."
-	//
-	// but also: "If a message is received with both a Transfer-Encoding and a
-	// Content-Length header field, the Transfer-Encoding overrides the
-	// Content-Length. Such a message might indicate an attempt to perform
-	// request smuggling (Section 9.5) or response splitting (Section 9.4) and
-	// ought to be handled as an error. A sender MUST remove the received
-	// Content-Length field prior to forwarding such a message downstream."
-	//
-	// Reportedly, these appear in the wild.
-	delete(t.Header, "Content-Length")
-
-	t.Chunked = true
-	return nil
-}
-
-// Determine the expected body length, using RFC 7230 Section 3.3. This
-// function is not a method, because ultimately it should be shared by
-// ReadResponse and ReadRequest.
-func fixLength(isResponse bool, status int, requestMethod string, header Header, chunked bool) (int64, error) {
-	isRequest := !isResponse
-	contentLens := header["Content-Length"]
-
-	// Hardening against HTTP request smuggling
-	if len(contentLens) > 1 {
-		// Per RFC 7230 Section 3.3.2, prevent multiple
-		// Content-Length headers if they differ in value.
-		// If there are dups of the value, remove the dups.
-		// See Issue 16490.
-		first := textproto.TrimString(contentLens[0])
-		for _, ct := range contentLens[1:] {
-			if first != textproto.TrimString(ct) {
-				return 0, fmt.Errorf("http: message cannot contain multiple Content-Length headers; got %q", contentLens)
-			}
-		}
-
-		// deduplicate Content-Length
-		header.Del("Content-Length")
-		header.Add("Content-Length", first)
-
-		contentLens = header["Content-Length"]
-	}
-
-	// Logic based on response type or status
-	if noResponseBodyExpected(requestMethod) {
-		// For HTTP requests, as part of hardening against request
-		// smuggling (RFC 7230), don't allow a Content-Length header for
-		// methods which don't permit bodies. As an exception, allow
-		// exactly one Content-Length header if its value is "0".
-		if isRequest && len(contentLens) > 0 && !(len(contentLens) == 1 && contentLens[0] == "0") {
-			return 0, fmt.Errorf("http: method cannot contain a Content-Length; got %q", contentLens)
-		}
-		return 0, nil
-	}
-	if status/100 == 1 {
-		return 0, nil
-	}
-	switch status {
-	case 204, 304:
-		return 0, nil
-	}
-
-	// Logic based on Transfer-Encoding
-	if chunked {
-		return -1, nil
-	}
-
-	// Logic based on Content-Length
-	var cl string
-	if len(contentLens) == 1 {
-		cl = textproto.TrimString(contentLens[0])
-	}
-	if cl != "" {
-		n, err := parseContentLength(cl)
-		if err != nil {
-			return -1, err
-		}
-		return n, nil
-	}
-	header.Del("Content-Length")
-
-	if isRequest {
-		// RFC 7230 neither explicitly permits nor forbids an
-		// entity-body on a GET request so we permit one if
-		// declared, but we default to 0 here (not -1 below)
-		// if there's no mention of a body.
-		// Likewise, all other request methods are assumed to have
-		// no body if neither Transfer-Encoding chunked nor a
-		// Content-Length are set.
-		return 0, nil
-	}
-
-	// Body-EOF logic based on other methods (like closing, or chunked coding)
-	return -1, nil
-}
-
-// Determine whether to hang up after sending a request and body, or
-// receiving a response and body
-// 'header' is the request headers
-func shouldClose(major, minor int, header Header, removeCloseHeader bool) bool {
-	if major < 1 {
-		return true
-	}
-
-	conv := header["Connection"]
-	hasClose := httpguts.HeaderValuesContainsToken(conv, "close")
-	if major == 1 && minor == 0 {
-		return hasClose || !httpguts.HeaderValuesContainsToken(conv, "keep-alive")
-	}
-
-	if hasClose && removeCloseHeader {
-		header.Del("Connection")
-	}
-
-	return hasClose
-}
-
-// Parse the trailer header
-func fixTrailer(header Header, chunked bool) (Header, error) {
-	vv, ok := header["Trailer"]
-	if !ok {
-		return nil, nil
-	}
-	if !chunked {
-		// Trailer and no chunking:
-		// this is an invalid use case for trailer header.
-		// Nevertheless, no error will be returned and we
-		// let users decide if this is a valid HTTP message.
-		// The Trailer header will be kept in Response.Header
-		// but not populate Response.Trailer.
-		// See issue #27197.
-		return nil, nil
-	}
-	header.Del("Trailer")
-
-	trailer := make(Header)
-	var err error
-	for _, v := range vv {
-		foreachHeaderElement(v, func(key string) {
-			key = CanonicalHeaderKey(key)
-			switch key {
-			case "Transfer-Encoding", "Trailer", "Content-Length":
-				if err == nil {
-					err = badStringError("bad trailer key", key)
-					return
-				}
-			}
-			trailer[key] = nil
-		})
-	}
-	if err != nil {
-		return nil, err
-	}
-	if len(trailer) == 0 {
-		return nil, nil
-	}
-	return trailer, nil
-}
-
-// body turns a Reader into a ReadCloser.
-// Close ensures that the body has been fully read
-// and then reads the trailer if necessary.
-type body struct {
-	src          io.Reader
-	hdr          any           // non-nil (Response or Request) value means read trailer
-	r            *bufio.Reader // underlying wire-format reader for the trailer
-	closing      bool          // is the connection to be closed after reading body?
-	doEarlyClose bool          // whether Close should stop early
-
-	mu         sync.Mutex // guards following, and calls to Read and Close
-	sawEOF     bool
-	closed     bool
-	earlyClose bool   // Close called and we didn't read to the end of src
-	onHitEOF   func() // if non-nil, func to call when EOF is Read
-}
-
-// ErrBodyReadAfterClose is returned when reading a Request or Response
-// Body after the body has been closed. This typically happens when the body is
-// read after an HTTP Handler calls WriteHeader or Write on its
-// ResponseWriter.
-var ErrBodyReadAfterClose = errors.New("http: invalid Read on closed Body")
-
-func (b *body) Read(p []byte) (n int, err error) {
-	b.mu.Lock()
-	defer b.mu.Unlock()
-	if b.closed {
-		return 0, ErrBodyReadAfterClose
-	}
-	return b.readLocked(p)
-}
-
-// Must hold b.mu.
-func (b *body) readLocked(p []byte) (n int, err error) {
-	if b.sawEOF {
-		return 0, io.EOF
-	}
-	n, err = b.src.Read(p)
-
-	if err == io.EOF {
-		b.sawEOF = true
-		// Chunked case. Read the trailer.
-		if b.hdr != nil {
-			if e := b.readTrailer(); e != nil {
-				err = e
-				// Something went wrong in the trailer, we must not allow any
-				// further reads of any kind to succeed from body, nor any
-				// subsequent requests on the server connection. See
-				// golang.org/issue/12027
-				b.sawEOF = false
-				b.closed = true
-			}
-			b.hdr = nil
-		} else {
-			// If the server declared the Content-Length, our body is a LimitedReader
-			// and we need to check whether this EOF arrived early.
-			if lr, ok := b.src.(*io.LimitedReader); ok && lr.N > 0 {
-				err = io.ErrUnexpectedEOF
-			}
-		}
-	}
-
-	// If we can return an EOF here along with the read data, do
-	// so. This is optional per the io.Reader contract, but doing
-	// so helps the HTTP transport code recycle its connection
-	// earlier (since it will see this EOF itself), even if the
-	// client doesn't do future reads or Close.
-	if err == nil && n > 0 {
-		if lr, ok := b.src.(*io.LimitedReader); ok && lr.N == 0 {
-			err = io.EOF
-			b.sawEOF = true
-		}
-	}
-
-	if b.sawEOF && b.onHitEOF != nil {
-		b.onHitEOF()
-	}
-
-	return n, err
-}
-
-var (
-	singleCRLF = []byte("\r\n")
-	doubleCRLF = []byte("\r\n\r\n")
-)
-
-func seeUpcomingDoubleCRLF(r *bufio.Reader) bool {
-	for peekSize := 4; ; peekSize++ {
-		// This loop stops when Peek returns an error,
-		// which it does when r's buffer has been filled.
-		buf, err := r.Peek(peekSize)
-		if bytes.HasSuffix(buf, doubleCRLF) {
-			return true
-		}
-		if err != nil {
-			break
-		}
-	}
-	return false
-}
-
-var errTrailerEOF = errors.New("http: unexpected EOF reading trailer")
-
-func (b *body) readTrailer() error {
-	// The common case, since nobody uses trailers.
-	buf, err := b.r.Peek(2)
-	if bytes.Equal(buf, singleCRLF) {
-		b.r.Discard(2)
-		return nil
-	}
-	if len(buf) < 2 {
-		return errTrailerEOF
-	}
-	if err != nil {
-		return err
-	}
-
-	// Make sure there's a header terminator coming up, to prevent
-	// a DoS with an unbounded size Trailer. It's not easy to
-	// slip in a LimitReader here, as textproto.NewReader requires
-	// a concrete *bufio.Reader. Also, we can't get all the way
-	// back up to our conn's LimitedReader that *might* be backing
-	// this bufio.Reader. Instead, a hack: we iteratively Peek up
-	// to the bufio.Reader's max size, looking for a double CRLF.
-	// This limits the trailer to the underlying buffer size, typically 4kB.
-	if !seeUpcomingDoubleCRLF(b.r) {
-		return errors.New("http: suspiciously long trailer after chunked body")
-	}
-
-	hdr, err := textproto.NewReader(b.r).ReadMIMEHeader()
-	if err != nil {
-		if err == io.EOF {
-			return errTrailerEOF
-		}
-		return err
-	}
-	switch rr := b.hdr.(type) {
-	case *Request:
-		mergeSetHeader(&rr.Trailer, Header(hdr))
-	case *Response:
-		mergeSetHeader(&rr.Trailer, Header(hdr))
-	}
-	return nil
-}
-
-func mergeSetHeader(dst *Header, src Header) {
-	if *dst == nil {
-		*dst = src
-		return
-	}
-	for k, vv := range src {
-		(*dst)[k] = vv
-	}
-}
-
-// unreadDataSizeLocked returns the number of bytes of unread input.
-// It returns -1 if unknown.
-// b.mu must be held.
-func (b *body) unreadDataSizeLocked() int64 {
-	if lr, ok := b.src.(*io.LimitedReader); ok {
-		return lr.N
-	}
-	return -1
-}
-
-func (b *body) Close() error {
-	b.mu.Lock()
-	defer b.mu.Unlock()
-	if b.closed {
-		return nil
-	}
-	var err error
-	switch {
-	case b.sawEOF:
-		// Already saw EOF, so no need going to look for it.
-	case b.hdr == nil && b.closing:
-		// no trailer and closing the connection next.
-		// no point in reading to EOF.
-	case b.doEarlyClose:
-		// Read up to maxPostHandlerReadBytes bytes of the body, looking
-		// for EOF (and trailers), so we can re-use this connection.
-		if lr, ok := b.src.(*io.LimitedReader); ok && lr.N > maxPostHandlerReadBytes {
-			// There was a declared Content-Length, and we have more bytes remaining
-			// than our maxPostHandlerReadBytes tolerance. So, give up.
-			b.earlyClose = true
-		} else {
-			var n int64
-			// Consume the body, or, which will also lead to us reading
-			// the trailer headers after the body, if present.
-			n, err = io.CopyN(io.Discard, bodyLocked{b}, maxPostHandlerReadBytes)
-			if err == io.EOF {
-				err = nil
-			}
-			if n == maxPostHandlerReadBytes {
-				b.earlyClose = true
-			}
-		}
-	default:
-		// Fully consume the body, which will also lead to us reading
-		// the trailer headers after the body, if present.
-		_, err = io.Copy(io.Discard, bodyLocked{b})
-	}
-	b.closed = true
-	return err
-}
-
-func (b *body) didEarlyClose() bool {
-	b.mu.Lock()
-	defer b.mu.Unlock()
-	return b.earlyClose
-}
-
-// bodyRemains reports whether future Read calls might
-// yield data.
-func (b *body) bodyRemains() bool {
-	b.mu.Lock()
-	defer b.mu.Unlock()
-	return !b.sawEOF
-}
-
-func (b *body) registerOnHitEOF(fn func()) {
-	b.mu.Lock()
-	defer b.mu.Unlock()
-	b.onHitEOF = fn
-}
-
-// bodyLocked is an io.Reader reading from a *body when its mutex is
-// already held.
-type bodyLocked struct {
-	b *body
-}
-
-func (bl bodyLocked) Read(p []byte) (n int, err error) {
-	if bl.b.closed {
-		return 0, ErrBodyReadAfterClose
-	}
-	return bl.b.readLocked(p)
-}
-
-// parseContentLength trims whitespace from s and returns -1 if no value
-// is set, or the value if it's >= 0.
-func parseContentLength(cl string) (int64, error) {
-	cl = textproto.TrimString(cl)
-	if cl == "" {
-		return -1, nil
-	}
-	n, err := strconv.ParseUint(cl, 10, 63)
-	if err != nil {
-		return 0, badStringError("bad Content-Length", cl)
-	}
-	return int64(n), nil
-
-}
-
-// finishAsyncByteRead finishes reading the 1-byte sniff
-// from the ContentLength==0, Body!=nil case.
-type finishAsyncByteRead struct {
-	tw *transferWriter
-}
-
-func (fr finishAsyncByteRead) Read(p []byte) (n int, err error) {
-	if len(p) == 0 {
-		return
-	}
-	rres := <-fr.tw.ByteReadCh
-	n, err = rres.n, rres.err
-	if n == 1 {
-		p[0] = rres.b
-	}
-	if err == nil {
-		err = io.EOF
-	}
-	return
-}
-
-var nopCloserType = reflect.TypeOf(io.NopCloser(nil))
-
-// isKnownInMemoryReader reports whether r is a type known to not
-// block on Read. Its caller uses this as an optional optimization to
-// send fewer TCP packets.
-func isKnownInMemoryReader(r io.Reader) bool {
-	switch r.(type) {
-	case *bytes.Reader, *bytes.Buffer, *strings.Reader:
-		return true
-	}
-	if reflect.TypeOf(r) == nopCloserType {
-		return isKnownInMemoryReader(reflect.ValueOf(r).Field(0).Interface().(io.Reader))
-	}
-	if r, ok := r.(*readTrackingBody); ok {
-		return isKnownInMemoryReader(r.ReadCloser)
-	}
-	return false
-}
-
-// bufioFlushWriter is an io.Writer wrapper that flushes all writes
-// on its wrapped writer if it's a *bufio.Writer.
-type bufioFlushWriter struct{ w io.Writer }
-
-func (fw bufioFlushWriter) Write(p []byte) (n int, err error) {
-	n, err = fw.w.Write(p)
-	if bw, ok := fw.w.(*bufio.Writer); n > 0 && ok {
-		ferr := bw.Flush()
-		if ferr != nil && err == nil {
-			err = ferr
-		}
-	}
-	return
-}
diff --git a/contrib/go/_std_1.18/src/net/http/transport.go b/contrib/go/_std_1.18/src/net/http/transport.go
deleted file mode 100644
index e41b20a15b..0000000000
--- a/contrib/go/_std_1.18/src/net/http/transport.go
+++ /dev/null
@@ -1,2906 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// HTTP client implementation. See RFC 7230 through 7235.
-//
-// This is the low-level Transport implementation of RoundTripper.
-// The high-level interface is in client.go.
-
-package http
-
-import (
-	"bufio"
-	"compress/gzip"
-	"container/list"
-	"context"
-	"crypto/tls"
-	"errors"
-	"fmt"
-	"internal/godebug"
-	"io"
-	"log"
-	"net"
-	"net/http/httptrace"
-	"net/http/internal/ascii"
-	"net/textproto"
-	"net/url"
-	"reflect"
-	"strings"
-	"sync"
-	"sync/atomic"
-	"time"
-
-	"golang.org/x/net/http/httpguts"
-	"golang.org/x/net/http/httpproxy"
-)
-
-// DefaultTransport is the default implementation of Transport and is
-// used by DefaultClient. It establishes network connections as needed
-// and caches them for reuse by subsequent calls. It uses HTTP proxies
-// as directed by the $HTTP_PROXY and $NO_PROXY (or $http_proxy and
-// $no_proxy) environment variables.
-var DefaultTransport RoundTripper = &Transport{
-	Proxy: ProxyFromEnvironment,
-	DialContext: defaultTransportDialContext(&net.Dialer{
-		Timeout:   30 * time.Second,
-		KeepAlive: 30 * time.Second,
-	}),
-	ForceAttemptHTTP2:     true,
-	MaxIdleConns:          100,
-	IdleConnTimeout:       90 * time.Second,
-	TLSHandshakeTimeout:   10 * time.Second,
-	ExpectContinueTimeout: 1 * time.Second,
-}
-
-// DefaultMaxIdleConnsPerHost is the default value of Transport's
-// MaxIdleConnsPerHost.
-const DefaultMaxIdleConnsPerHost = 2
-
-// Transport is an implementation of RoundTripper that supports HTTP,
-// HTTPS, and HTTP proxies (for either HTTP or HTTPS with CONNECT).
-//
-// By default, Transport caches connections for future re-use.
-// This may leave many open connections when accessing many hosts.
-// This behavior can be managed using Transport's CloseIdleConnections method
-// and the MaxIdleConnsPerHost and DisableKeepAlives fields.
-//
-// Transports should be reused instead of created as needed.
-// Transports are safe for concurrent use by multiple goroutines.
-//
-// A Transport is a low-level primitive for making HTTP and HTTPS requests.
-// For high-level functionality, such as cookies and redirects, see Client.
-//
-// Transport uses HTTP/1.1 for HTTP URLs and either HTTP/1.1 or HTTP/2
-// for HTTPS URLs, depending on whether the server supports HTTP/2,
-// and how the Transport is configured. The DefaultTransport supports HTTP/2.
-// To explicitly enable HTTP/2 on a transport, use golang.org/x/net/http2
-// and call ConfigureTransport. See the package docs for more about HTTP/2.
-//
-// Responses with status codes in the 1xx range are either handled
-// automatically (100 expect-continue) or ignored. The one
-// exception is HTTP status code 101 (Switching Protocols), which is
-// considered a terminal status and returned by RoundTrip. To see the
-// ignored 1xx responses, use the httptrace trace package's
-// ClientTrace.Got1xxResponse.
-//
-// Transport only retries a request upon encountering a network error
-// if the request is idempotent and either has no body or has its
-// Request.GetBody defined. HTTP requests are considered idempotent if
-// they have HTTP methods GET, HEAD, OPTIONS, or TRACE; or if their
-// Header map contains an "Idempotency-Key" or "X-Idempotency-Key"
-// entry. If the idempotency key value is a zero-length slice, the
-// request is treated as idempotent but the header is not sent on the
-// wire.
-type Transport struct {
-	idleMu       sync.Mutex
-	closeIdle    bool                                // user has requested to close all idle conns
-	idleConn     map[connectMethodKey][]*persistConn // most recently used at end
-	idleConnWait map[connectMethodKey]wantConnQueue  // waiting getConns
-	idleLRU      connLRU
-
-	reqMu       sync.Mutex
-	reqCanceler map[cancelKey]func(error)
-
-	altMu    sync.Mutex   // guards changing altProto only
-	altProto atomic.Value // of nil or map[string]RoundTripper, key is URI scheme
-
-	connsPerHostMu   sync.Mutex
-	connsPerHost     map[connectMethodKey]int
-	connsPerHostWait map[connectMethodKey]wantConnQueue // waiting getConns
-
-	// Proxy specifies a function to return a proxy for a given
-	// Request. If the function returns a non-nil error, the
-	// request is aborted with the provided error.
-	//
-	// The proxy type is determined by the URL scheme. "http",
-	// "https", and "socks5" are supported. If the scheme is empty,
-	// "http" is assumed.
-	//
-	// If Proxy is nil or returns a nil *URL, no proxy is used.
-	Proxy func(*Request) (*url.URL, error)
-
-	// DialContext specifies the dial function for creating unencrypted TCP connections.
-	// If DialContext is nil (and the deprecated Dial below is also nil),
-	// then the transport dials using package net.
-	//
-	// DialContext runs concurrently with calls to RoundTrip.
-	// A RoundTrip call that initiates a dial may end up using
-	// a connection dialed previously when the earlier connection
-	// becomes idle before the later DialContext completes.
-	DialContext func(ctx context.Context, network, addr string) (net.Conn, error)
-
-	// Dial specifies the dial function for creating unencrypted TCP connections.
-	//
-	// Dial runs concurrently with calls to RoundTrip.
-	// A RoundTrip call that initiates a dial may end up using
-	// a connection dialed previously when the earlier connection
-	// becomes idle before the later Dial completes.
-	//
-	// Deprecated: Use DialContext instead, which allows the transport
-	// to cancel dials as soon as they are no longer needed.
-	// If both are set, DialContext takes priority.
-	Dial func(network, addr string) (net.Conn, error)
-
-	// DialTLSContext specifies an optional dial function for creating
-	// TLS connections for non-proxied HTTPS requests.
-	//
-	// If DialTLSContext is nil (and the deprecated DialTLS below is also nil),
-	// DialContext and TLSClientConfig are used.
-	//
-	// If DialTLSContext is set, the Dial and DialContext hooks are not used for HTTPS
-	// requests and the TLSClientConfig and TLSHandshakeTimeout
-	// are ignored. The returned net.Conn is assumed to already be
-	// past the TLS handshake.
-	DialTLSContext func(ctx context.Context, network, addr string) (net.Conn, error)
-
-	// DialTLS specifies an optional dial function for creating
-	// TLS connections for non-proxied HTTPS requests.
-	//
-	// Deprecated: Use DialTLSContext instead, which allows the transport
-	// to cancel dials as soon as they are no longer needed.
-	// If both are set, DialTLSContext takes priority.
-	DialTLS func(network, addr string) (net.Conn, error)
-
-	// TLSClientConfig specifies the TLS configuration to use with
-	// tls.Client.
-	// If nil, the default configuration is used.
-	// If non-nil, HTTP/2 support may not be enabled by default.
-	TLSClientConfig *tls.Config
-
-	// TLSHandshakeTimeout specifies the maximum amount of time waiting to
-	// wait for a TLS handshake. Zero means no timeout.
-	TLSHandshakeTimeout time.Duration
-
-	// DisableKeepAlives, if true, disables HTTP keep-alives and
-	// will only use the connection to the server for a single
-	// HTTP request.
-	//
-	// This is unrelated to the similarly named TCP keep-alives.
-	DisableKeepAlives bool
-
-	// DisableCompression, if true, prevents the Transport from
-	// requesting compression with an "Accept-Encoding: gzip"
-	// request header when the Request contains no existing
-	// Accept-Encoding value. If the Transport requests gzip on
-	// its own and gets a gzipped response, it's transparently
-	// decoded in the Response.Body. However, if the user
-	// explicitly requested gzip it is not automatically
-	// uncompressed.
-	DisableCompression bool
-
-	// MaxIdleConns controls the maximum number of idle (keep-alive)
-	// connections across all hosts. Zero means no limit.
-	MaxIdleConns int
-
-	// MaxIdleConnsPerHost, if non-zero, controls the maximum idle
-	// (keep-alive) connections to keep per-host. If zero,
-	// DefaultMaxIdleConnsPerHost is used.
-	MaxIdleConnsPerHost int
-
-	// MaxConnsPerHost optionally limits the total number of
-	// connections per host, including connections in the dialing,
-	// active, and idle states. On limit violation, dials will block.
-	//
-	// Zero means no limit.
-	MaxConnsPerHost int
-
-	// IdleConnTimeout is the maximum amount of time an idle
-	// (keep-alive) connection will remain idle before closing
-	// itself.
-	// Zero means no limit.
-	IdleConnTimeout time.Duration
-
-	// ResponseHeaderTimeout, if non-zero, specifies the amount of
-	// time to wait for a server's response headers after fully
-	// writing the request (including its body, if any). This
-	// time does not include the time to read the response body.
-	ResponseHeaderTimeout time.Duration
-
-	// ExpectContinueTimeout, if non-zero, specifies the amount of
-	// time to wait for a server's first response headers after fully
-	// writing the request headers if the request has an
-	// "Expect: 100-continue" header. Zero means no timeout and
-	// causes the body to be sent immediately, without
-	// waiting for the server to approve.
-	// This time does not include the time to send the request header.
-	ExpectContinueTimeout time.Duration
-
-	// TLSNextProto specifies how the Transport switches to an
-	// alternate protocol (such as HTTP/2) after a TLS ALPN
-	// protocol negotiation. If Transport dials an TLS connection
-	// with a non-empty protocol name and TLSNextProto contains a
-	// map entry for that key (such as "h2"), then the func is
-	// called with the request's authority (such as "example.com"
-	// or "example.com:1234") and the TLS connection. The function
-	// must return a RoundTripper that then handles the request.
-	// If TLSNextProto is not nil, HTTP/2 support is not enabled
-	// automatically.
-	TLSNextProto map[string]func(authority string, c *tls.Conn) RoundTripper
-
-	// ProxyConnectHeader optionally specifies headers to send to
-	// proxies during CONNECT requests.
-	// To set the header dynamically, see GetProxyConnectHeader.
-	ProxyConnectHeader Header
-
-	// GetProxyConnectHeader optionally specifies a func to return
-	// headers to send to proxyURL during a CONNECT request to the
-	// ip:port target.
-	// If it returns an error, the Transport's RoundTrip fails with
-	// that error. It can return (nil, nil) to not add headers.
-	// If GetProxyConnectHeader is non-nil, ProxyConnectHeader is
-	// ignored.
-	GetProxyConnectHeader func(ctx context.Context, proxyURL *url.URL, target string) (Header, error)
-
-	// MaxResponseHeaderBytes specifies a limit on how many
-	// response bytes are allowed in the server's response
-	// header.
-	//
-	// Zero means to use a default limit.
-	MaxResponseHeaderBytes int64
-
-	// WriteBufferSize specifies the size of the write buffer used
-	// when writing to the transport.
-	// If zero, a default (currently 4KB) is used.
-	WriteBufferSize int
-
-	// ReadBufferSize specifies the size of the read buffer used
-	// when reading from the transport.
-	// If zero, a default (currently 4KB) is used.
-	ReadBufferSize int
-
-	// nextProtoOnce guards initialization of TLSNextProto and
-	// h2transport (via onceSetNextProtoDefaults)
-	nextProtoOnce      sync.Once
-	h2transport        h2Transport // non-nil if http2 wired up
-	tlsNextProtoWasNil bool        // whether TLSNextProto was nil when the Once fired
-
-	// ForceAttemptHTTP2 controls whether HTTP/2 is enabled when a non-zero
-	// Dial, DialTLS, or DialContext func or TLSClientConfig is provided.
-	// By default, use of any those fields conservatively disables HTTP/2.
-	// To use a custom dialer or TLS config and still attempt HTTP/2
-	// upgrades, set this to true.
-	ForceAttemptHTTP2 bool
-}
-
-// A cancelKey is the key of the reqCanceler map.
-// We wrap the *Request in this type since we want to use the original request,
-// not any transient one created by roundTrip.
-type cancelKey struct {
-	req *Request
-}
-
-func (t *Transport) writeBufferSize() int {
-	if t.WriteBufferSize > 0 {
-		return t.WriteBufferSize
-	}
-	return 4 << 10
-}
-
-func (t *Transport) readBufferSize() int {
-	if t.ReadBufferSize > 0 {
-		return t.ReadBufferSize
-	}
-	return 4 << 10
-}
-
-// Clone returns a deep copy of t's exported fields.
-func (t *Transport) Clone() *Transport {
-	t.nextProtoOnce.Do(t.onceSetNextProtoDefaults)
-	t2 := &Transport{
-		Proxy:                  t.Proxy,
-		DialContext:            t.DialContext,
-		Dial:                   t.Dial,
-		DialTLS:                t.DialTLS,
-		DialTLSContext:         t.DialTLSContext,
-		TLSHandshakeTimeout:    t.TLSHandshakeTimeout,
-		DisableKeepAlives:      t.DisableKeepAlives,
-		DisableCompression:     t.DisableCompression,
-		MaxIdleConns:           t.MaxIdleConns,
-		MaxIdleConnsPerHost:    t.MaxIdleConnsPerHost,
-		MaxConnsPerHost:        t.MaxConnsPerHost,
-		IdleConnTimeout:        t.IdleConnTimeout,
-		ResponseHeaderTimeout:  t.ResponseHeaderTimeout,
-		ExpectContinueTimeout:  t.ExpectContinueTimeout,
-		ProxyConnectHeader:     t.ProxyConnectHeader.Clone(),
-		GetProxyConnectHeader:  t.GetProxyConnectHeader,
-		MaxResponseHeaderBytes: t.MaxResponseHeaderBytes,
-		ForceAttemptHTTP2:      t.ForceAttemptHTTP2,
-		WriteBufferSize:        t.WriteBufferSize,
-		ReadBufferSize:         t.ReadBufferSize,
-	}
-	if t.TLSClientConfig != nil {
-		t2.TLSClientConfig = t.TLSClientConfig.Clone()
-	}
-	if !t.tlsNextProtoWasNil {
-		npm := map[string]func(authority string, c *tls.Conn) RoundTripper{}
-		for k, v := range t.TLSNextProto {
-			npm[k] = v
-		}
-		t2.TLSNextProto = npm
-	}
-	return t2
-}
-
-// h2Transport is the interface we expect to be able to call from
-// net/http against an *http2.Transport that's either bundled into
-// h2_bundle.go or supplied by the user via x/net/http2.
-//
-// We name it with the "h2" prefix to stay out of the "http2" prefix
-// namespace used by x/tools/cmd/bundle for h2_bundle.go.
-type h2Transport interface {
-	CloseIdleConnections()
-}
-
-func (t *Transport) hasCustomTLSDialer() bool {
-	return t.DialTLS != nil || t.DialTLSContext != nil
-}
-
-// onceSetNextProtoDefaults initializes TLSNextProto.
-// It must be called via t.nextProtoOnce.Do.
-func (t *Transport) onceSetNextProtoDefaults() {
-	t.tlsNextProtoWasNil = (t.TLSNextProto == nil)
-	if godebug.Get("http2client") == "0" {
-		return
-	}
-
-	// If they've already configured http2 with
-	// golang.org/x/net/http2 instead of the bundled copy, try to
-	// get at its http2.Transport value (via the "https"
-	// altproto map) so we can call CloseIdleConnections on it if
-	// requested. (Issue 22891)
-	altProto, _ := t.altProto.Load().(map[string]RoundTripper)
-	if rv := reflect.ValueOf(altProto["https"]); rv.IsValid() && rv.Type().Kind() == reflect.Struct && rv.Type().NumField() == 1 {
-		if v := rv.Field(0); v.CanInterface() {
-			if h2i, ok := v.Interface().(h2Transport); ok {
-				t.h2transport = h2i
-				return
-			}
-		}
-	}
-
-	if t.TLSNextProto != nil {
-		// This is the documented way to disable http2 on a
-		// Transport.
-		return
-	}
-	if !t.ForceAttemptHTTP2 && (t.TLSClientConfig != nil || t.Dial != nil || t.DialContext != nil || t.hasCustomTLSDialer()) {
-		// Be conservative and don't automatically enable
-		// http2 if they've specified a custom TLS config or
-		// custom dialers. Let them opt-in themselves via
-		// http2.ConfigureTransport so we don't surprise them
-		// by modifying their tls.Config. Issue 14275.
-		// However, if ForceAttemptHTTP2 is true, it overrides the above checks.
-		return
-	}
-	if omitBundledHTTP2 {
-		return
-	}
-	t2, err := http2configureTransports(t)
-	if err != nil {
-		log.Printf("Error enabling Transport HTTP/2 support: %v", err)
-		return
-	}
-	t.h2transport = t2
-
-	// Auto-configure the http2.Transport's MaxHeaderListSize from
-	// the http.Transport's MaxResponseHeaderBytes. They don't
-	// exactly mean the same thing, but they're close.
-	//
-	// TODO: also add this to x/net/http2.Configure Transport, behind
-	// a +build go1.7 build tag:
-	if limit1 := t.MaxResponseHeaderBytes; limit1 != 0 && t2.MaxHeaderListSize == 0 {
-		const h2max = 1<<32 - 1
-		if limit1 >= h2max {
-			t2.MaxHeaderListSize = h2max
-		} else {
-			t2.MaxHeaderListSize = uint32(limit1)
-		}
-	}
-}
-
-// ProxyFromEnvironment returns the URL of the proxy to use for a
-// given request, as indicated by the environment variables
-// HTTP_PROXY, HTTPS_PROXY and NO_PROXY (or the lowercase versions
-// thereof). HTTPS_PROXY takes precedence over HTTP_PROXY for https
-// requests.
-//
-// The environment values may be either a complete URL or a
-// "host[:port]", in which case the "http" scheme is assumed.
-// The schemes "http", "https", and "socks5" are supported.
-// An error is returned if the value is a different form.
-//
-// A nil URL and nil error are returned if no proxy is defined in the
-// environment, or a proxy should not be used for the given request,
-// as defined by NO_PROXY.
-//
-// As a special case, if req.URL.Host is "localhost" (with or without
-// a port number), then a nil URL and nil error will be returned.
-func ProxyFromEnvironment(req *Request) (*url.URL, error) {
-	return envProxyFunc()(req.URL)
-}
-
-// ProxyURL returns a proxy function (for use in a Transport)
-// that always returns the same URL.
-func ProxyURL(fixedURL *url.URL) func(*Request) (*url.URL, error) {
-	return func(*Request) (*url.URL, error) {
-		return fixedURL, nil
-	}
-}
-
-// transportRequest is a wrapper around a *Request that adds
-// optional extra headers to write and stores any error to return
-// from roundTrip.
-type transportRequest struct {
-	*Request                         // original request, not to be mutated
-	extra     Header                 // extra headers to write, or nil
-	trace     *httptrace.ClientTrace // optional
-	cancelKey cancelKey
-
-	mu  sync.Mutex // guards err
-	err error      // first setError value for mapRoundTripError to consider
-}
-
-func (tr *transportRequest) extraHeaders() Header {
-	if tr.extra == nil {
-		tr.extra = make(Header)
-	}
-	return tr.extra
-}
-
-func (tr *transportRequest) setError(err error) {
-	tr.mu.Lock()
-	if tr.err == nil {
-		tr.err = err
-	}
-	tr.mu.Unlock()
-}
-
-// useRegisteredProtocol reports whether an alternate protocol (as registered
-// with Transport.RegisterProtocol) should be respected for this request.
-func (t *Transport) useRegisteredProtocol(req *Request) bool {
-	if req.URL.Scheme == "https" && req.requiresHTTP1() {
-		// If this request requires HTTP/1, don't use the
-		// "https" alternate protocol, which is used by the
-		// HTTP/2 code to take over requests if there's an
-		// existing cached HTTP/2 connection.
-		return false
-	}
-	return true
-}
-
-// alternateRoundTripper returns the alternate RoundTripper to use
-// for this request if the Request's URL scheme requires one,
-// or nil for the normal case of using the Transport.
-func (t *Transport) alternateRoundTripper(req *Request) RoundTripper {
-	if !t.useRegisteredProtocol(req) {
-		return nil
-	}
-	altProto, _ := t.altProto.Load().(map[string]RoundTripper)
-	return altProto[req.URL.Scheme]
-}
-
-// roundTrip implements a RoundTripper over HTTP.
-func (t *Transport) roundTrip(req *Request) (*Response, error) {
-	t.nextProtoOnce.Do(t.onceSetNextProtoDefaults)
-	ctx := req.Context()
-	trace := httptrace.ContextClientTrace(ctx)
-
-	if req.URL == nil {
-		req.closeBody()
-		return nil, errors.New("http: nil Request.URL")
-	}
-	if req.Header == nil {
-		req.closeBody()
-		return nil, errors.New("http: nil Request.Header")
-	}
-	scheme := req.URL.Scheme
-	isHTTP := scheme == "http" || scheme == "https"
-	if isHTTP {
-		for k, vv := range req.Header {
-			if !httpguts.ValidHeaderFieldName(k) {
-				req.closeBody()
-				return nil, fmt.Errorf("net/http: invalid header field name %q", k)
-			}
-			for _, v := range vv {
-				if !httpguts.ValidHeaderFieldValue(v) {
-					req.closeBody()
-					return nil, fmt.Errorf("net/http: invalid header field value %q for key %v", v, k)
-				}
-			}
-		}
-	}
-
-	origReq := req
-	cancelKey := cancelKey{origReq}
-	req = setupRewindBody(req)
-
-	if altRT := t.alternateRoundTripper(req); altRT != nil {
-		if resp, err := altRT.RoundTrip(req); err != ErrSkipAltProtocol {
-			return resp, err
-		}
-		var err error
-		req, err = rewindBody(req)
-		if err != nil {
-			return nil, err
-		}
-	}
-	if !isHTTP {
-		req.closeBody()
-		return nil, badStringError("unsupported protocol scheme", scheme)
-	}
-	if req.Method != "" && !validMethod(req.Method) {
-		req.closeBody()
-		return nil, fmt.Errorf("net/http: invalid method %q", req.Method)
-	}
-	if req.URL.Host == "" {
-		req.closeBody()
-		return nil, errors.New("http: no Host in request URL")
-	}
-
-	for {
-		select {
-		case <-ctx.Done():
-			req.closeBody()
-			return nil, ctx.Err()
-		default:
-		}
-
-		// treq gets modified by roundTrip, so we need to recreate for each retry.
-		treq := &transportRequest{Request: req, trace: trace, cancelKey: cancelKey}
-		cm, err := t.connectMethodForRequest(treq)
-		if err != nil {
-			req.closeBody()
-			return nil, err
-		}
-
-		// Get the cached or newly-created connection to either the
-		// host (for http or https), the http proxy, or the http proxy
-		// pre-CONNECTed to https server. In any case, we'll be ready
-		// to send it requests.
-		pconn, err := t.getConn(treq, cm)
-		if err != nil {
-			t.setReqCanceler(cancelKey, nil)
-			req.closeBody()
-			return nil, err
-		}
-
-		var resp *Response
-		if pconn.alt != nil {
-			// HTTP/2 path.
-			t.setReqCanceler(cancelKey, nil) // not cancelable with CancelRequest
-			resp, err = pconn.alt.RoundTrip(req)
-		} else {
-			resp, err = pconn.roundTrip(treq)
-		}
-		if err == nil {
-			resp.Request = origReq
-			return resp, nil
-		}
-
-		// Failed. Clean up and determine whether to retry.
-		if http2isNoCachedConnError(err) {
-			if t.removeIdleConn(pconn) {
-				t.decConnsPerHost(pconn.cacheKey)
-			}
-		} else if !pconn.shouldRetryRequest(req, err) {
-			// Issue 16465: return underlying net.Conn.Read error from peek,
-			// as we've historically done.
-			if e, ok := err.(nothingWrittenError); ok {
-				err = e.error
-			}
-			if e, ok := err.(transportReadFromServerError); ok {
-				err = e.err
-			}
-			return nil, err
-		}
-		testHookRoundTripRetried()
-
-		// Rewind the body if we're able to.
-		req, err = rewindBody(req)
-		if err != nil {
-			return nil, err
-		}
-	}
-}
-
-var errCannotRewind = errors.New("net/http: cannot rewind body after connection loss")
-
-type readTrackingBody struct {
-	io.ReadCloser
-	didRead  bool
-	didClose bool
-}
-
-func (r *readTrackingBody) Read(data []byte) (int, error) {
-	r.didRead = true
-	return r.ReadCloser.Read(data)
-}
-
-func (r *readTrackingBody) Close() error {
-	r.didClose = true
-	return r.ReadCloser.Close()
-}
-
-// setupRewindBody returns a new request with a custom body wrapper
-// that can report whether the body needs rewinding.
-// This lets rewindBody avoid an error result when the request
-// does not have GetBody but the body hasn't been read at all yet.
-func setupRewindBody(req *Request) *Request {
-	if req.Body == nil || req.Body == NoBody {
-		return req
-	}
-	newReq := *req
-	newReq.Body = &readTrackingBody{ReadCloser: req.Body}
-	return &newReq
-}
-
-// rewindBody returns a new request with the body rewound.
-// It returns req unmodified if the body does not need rewinding.
-// rewindBody takes care of closing req.Body when appropriate
-// (in all cases except when rewindBody returns req unmodified).
-func rewindBody(req *Request) (rewound *Request, err error) {
-	if req.Body == nil || req.Body == NoBody || (!req.Body.(*readTrackingBody).didRead && !req.Body.(*readTrackingBody).didClose) {
-		return req, nil // nothing to rewind
-	}
-	if !req.Body.(*readTrackingBody).didClose {
-		req.closeBody()
-	}
-	if req.GetBody == nil {
-		return nil, errCannotRewind
-	}
-	body, err := req.GetBody()
-	if err != nil {
-		return nil, err
-	}
-	newReq := *req
-	newReq.Body = &readTrackingBody{ReadCloser: body}
-	return &newReq, nil
-}
-
-// shouldRetryRequest reports whether we should retry sending a failed
-// HTTP request on a new connection. The non-nil input error is the
-// error from roundTrip.
-func (pc *persistConn) shouldRetryRequest(req *Request, err error) bool {
-	if http2isNoCachedConnError(err) {
-		// Issue 16582: if the user started a bunch of
-		// requests at once, they can all pick the same conn
-		// and violate the server's max concurrent streams.
-		// Instead, match the HTTP/1 behavior for now and dial
-		// again to get a new TCP connection, rather than failing
-		// this request.
-		return true
-	}
-	if err == errMissingHost {
-		// User error.
-		return false
-	}
-	if !pc.isReused() {
-		// This was a fresh connection. There's no reason the server
-		// should've hung up on us.
-		//
-		// Also, if we retried now, we could loop forever
-		// creating new connections and retrying if the server
-		// is just hanging up on us because it doesn't like
-		// our request (as opposed to sending an error).
-		return false
-	}
-	if _, ok := err.(nothingWrittenError); ok {
-		// We never wrote anything, so it's safe to retry, if there's no body or we
-		// can "rewind" the body with GetBody.
-		return req.outgoingLength() == 0 || req.GetBody != nil
-	}
-	if !req.isReplayable() {
-		// Don't retry non-idempotent requests.
-		return false
-	}
-	if _, ok := err.(transportReadFromServerError); ok {
-		// We got some non-EOF net.Conn.Read failure reading
-		// the 1st response byte from the server.
-		return true
-	}
-	if err == errServerClosedIdle {
-		// The server replied with io.EOF while we were trying to
-		// read the response. Probably an unfortunately keep-alive
-		// timeout, just as the client was writing a request.
-		return true
-	}
-	return false // conservatively
-}
-
-// ErrSkipAltProtocol is a sentinel error value defined by Transport.RegisterProtocol.
-var ErrSkipAltProtocol = errors.New("net/http: skip alternate protocol")
-
-// RegisterProtocol registers a new protocol with scheme.
-// The Transport will pass requests using the given scheme to rt.
-// It is rt's responsibility to simulate HTTP request semantics.
-//
-// RegisterProtocol can be used by other packages to provide
-// implementations of protocol schemes like "ftp" or "file".
-//
-// If rt.RoundTrip returns ErrSkipAltProtocol, the Transport will
-// handle the RoundTrip itself for that one request, as if the
-// protocol were not registered.
-func (t *Transport) RegisterProtocol(scheme string, rt RoundTripper) {
-	t.altMu.Lock()
-	defer t.altMu.Unlock()
-	oldMap, _ := t.altProto.Load().(map[string]RoundTripper)
-	if _, exists := oldMap[scheme]; exists {
-		panic("protocol " + scheme + " already registered")
-	}
-	newMap := make(map[string]RoundTripper)
-	for k, v := range oldMap {
-		newMap[k] = v
-	}
-	newMap[scheme] = rt
-	t.altProto.Store(newMap)
-}
-
-// CloseIdleConnections closes any connections which were previously
-// connected from previous requests but are now sitting idle in
-// a "keep-alive" state. It does not interrupt any connections currently
-// in use.
-func (t *Transport) CloseIdleConnections() {
-	t.nextProtoOnce.Do(t.onceSetNextProtoDefaults)
-	t.idleMu.Lock()
-	m := t.idleConn
-	t.idleConn = nil
-	t.closeIdle = true // close newly idle connections
-	t.idleLRU = connLRU{}
-	t.idleMu.Unlock()
-	for _, conns := range m {
-		for _, pconn := range conns {
-			pconn.close(errCloseIdleConns)
-		}
-	}
-	if t2 := t.h2transport; t2 != nil {
-		t2.CloseIdleConnections()
-	}
-}
-
-// CancelRequest cancels an in-flight request by closing its connection.
-// CancelRequest should only be called after RoundTrip has returned.
-//
-// Deprecated: Use Request.WithContext to create a request with a
-// cancelable context instead. CancelRequest cannot cancel HTTP/2
-// requests.
-func (t *Transport) CancelRequest(req *Request) {
-	t.cancelRequest(cancelKey{req}, errRequestCanceled)
-}
-
-// Cancel an in-flight request, recording the error value.
-// Returns whether the request was canceled.
-func (t *Transport) cancelRequest(key cancelKey, err error) bool {
-	// This function must not return until the cancel func has completed.
-	// See: https://golang.org/issue/34658
-	t.reqMu.Lock()
-	defer t.reqMu.Unlock()
-	cancel := t.reqCanceler[key]
-	delete(t.reqCanceler, key)
-	if cancel != nil {
-		cancel(err)
-	}
-
-	return cancel != nil
-}
-
-//
-// Private implementation past this point.
-//
-
-var (
-	// proxyConfigOnce guards proxyConfig
-	envProxyOnce      sync.Once
-	envProxyFuncValue func(*url.URL) (*url.URL, error)
-)
-
-// defaultProxyConfig returns a ProxyConfig value looked up
-// from the environment. This mitigates expensive lookups
-// on some platforms (e.g. Windows).
-func envProxyFunc() func(*url.URL) (*url.URL, error) {
-	envProxyOnce.Do(func() {
-		envProxyFuncValue = httpproxy.FromEnvironment().ProxyFunc()
-	})
-	return envProxyFuncValue
-}
-
-// resetProxyConfig is used by tests.
-func resetProxyConfig() {
-	envProxyOnce = sync.Once{}
-	envProxyFuncValue = nil
-}
-
-func (t *Transport) connectMethodForRequest(treq *transportRequest) (cm connectMethod, err error) {
-	cm.targetScheme = treq.URL.Scheme
-	cm.targetAddr = canonicalAddr(treq.URL)
-	if t.Proxy != nil {
-		cm.proxyURL, err = t.Proxy(treq.Request)
-	}
-	cm.onlyH1 = treq.requiresHTTP1()
-	return cm, err
-}
-
-// proxyAuth returns the Proxy-Authorization header to set
-// on requests, if applicable.
-func (cm *connectMethod) proxyAuth() string {
-	if cm.proxyURL == nil {
-		return ""
-	}
-	if u := cm.proxyURL.User; u != nil {
-		username := u.Username()
-		password, _ := u.Password()
-		return "Basic " + basicAuth(username, password)
-	}
-	return ""
-}
-
-// error values for debugging and testing, not seen by users.
-var (
-	errKeepAlivesDisabled = errors.New("http: putIdleConn: keep alives disabled")
-	errConnBroken         = errors.New("http: putIdleConn: connection is in bad state")
-	errCloseIdle          = errors.New("http: putIdleConn: CloseIdleConnections was called")
-	errTooManyIdle        = errors.New("http: putIdleConn: too many idle connections")
-	errTooManyIdleHost    = errors.New("http: putIdleConn: too many idle connections for host")
-	errCloseIdleConns     = errors.New("http: CloseIdleConnections called")
-	errReadLoopExiting    = errors.New("http: persistConn.readLoop exiting")
-	errIdleConnTimeout    = errors.New("http: idle connection timeout")
-
-	// errServerClosedIdle is not seen by users for idempotent requests, but may be
-	// seen by a user if the server shuts down an idle connection and sends its FIN
-	// in flight with already-written POST body bytes from the client.
-	// See https://github.com/golang/go/issues/19943#issuecomment-355607646
-	errServerClosedIdle = errors.New("http: server closed idle connection")
-)
-
-// transportReadFromServerError is used by Transport.readLoop when the
-// 1 byte peek read fails and we're actually anticipating a response.
-// Usually this is just due to the inherent keep-alive shut down race,
-// where the server closed the connection at the same time the client
-// wrote. The underlying err field is usually io.EOF or some
-// ECONNRESET sort of thing which varies by platform. But it might be
-// the user's custom net.Conn.Read error too, so we carry it along for
-// them to return from Transport.RoundTrip.
-type transportReadFromServerError struct {
-	err error
-}
-
-func (e transportReadFromServerError) Unwrap() error { return e.err }
-
-func (e transportReadFromServerError) Error() string {
-	return fmt.Sprintf("net/http: Transport failed to read from server: %v", e.err)
-}
-
-func (t *Transport) putOrCloseIdleConn(pconn *persistConn) {
-	if err := t.tryPutIdleConn(pconn); err != nil {
-		pconn.close(err)
-	}
-}
-
-func (t *Transport) maxIdleConnsPerHost() int {
-	if v := t.MaxIdleConnsPerHost; v != 0 {
-		return v
-	}
-	return DefaultMaxIdleConnsPerHost
-}
-
-// tryPutIdleConn adds pconn to the list of idle persistent connections awaiting
-// a new request.
-// If pconn is no longer needed or not in a good state, tryPutIdleConn returns
-// an error explaining why it wasn't registered.
-// tryPutIdleConn does not close pconn. Use putOrCloseIdleConn instead for that.
-func (t *Transport) tryPutIdleConn(pconn *persistConn) error {
-	if t.DisableKeepAlives || t.MaxIdleConnsPerHost < 0 {
-		return errKeepAlivesDisabled
-	}
-	if pconn.isBroken() {
-		return errConnBroken
-	}
-	pconn.markReused()
-
-	t.idleMu.Lock()
-	defer t.idleMu.Unlock()
-
-	// HTTP/2 (pconn.alt != nil) connections do not come out of the idle list,
-	// because multiple goroutines can use them simultaneously.
-	// If this is an HTTP/2 connection being “returned,” we're done.
-	if pconn.alt != nil && t.idleLRU.m[pconn] != nil {
-		return nil
-	}
-
-	// Deliver pconn to goroutine waiting for idle connection, if any.
-	// (They may be actively dialing, but this conn is ready first.
-	// Chrome calls this socket late binding.
-	// See https://www.chromium.org/developers/design-documents/network-stack#TOC-Connection-Management.)
-	key := pconn.cacheKey
-	if q, ok := t.idleConnWait[key]; ok {
-		done := false
-		if pconn.alt == nil {
-			// HTTP/1.
-			// Loop over the waiting list until we find a w that isn't done already, and hand it pconn.
-			for q.len() > 0 {
-				w := q.popFront()
-				if w.tryDeliver(pconn, nil) {
-					done = true
-					break
-				}
-			}
-		} else {
-			// HTTP/2.
-			// Can hand the same pconn to everyone in the waiting list,
-			// and we still won't be done: we want to put it in the idle
-			// list unconditionally, for any future clients too.
-			for q.len() > 0 {
-				w := q.popFront()
-				w.tryDeliver(pconn, nil)
-			}
-		}
-		if q.len() == 0 {
-			delete(t.idleConnWait, key)
-		} else {
-			t.idleConnWait[key] = q
-		}
-		if done {
-			return nil
-		}
-	}
-
-	if t.closeIdle {
-		return errCloseIdle
-	}
-	if t.idleConn == nil {
-		t.idleConn = make(map[connectMethodKey][]*persistConn)
-	}
-	idles := t.idleConn[key]
-	if len(idles) >= t.maxIdleConnsPerHost() {
-		return errTooManyIdleHost
-	}
-	for _, exist := range idles {
-		if exist == pconn {
-			log.Fatalf("dup idle pconn %p in freelist", pconn)
-		}
-	}
-	t.idleConn[key] = append(idles, pconn)
-	t.idleLRU.add(pconn)
-	if t.MaxIdleConns != 0 && t.idleLRU.len() > t.MaxIdleConns {
-		oldest := t.idleLRU.removeOldest()
-		oldest.close(errTooManyIdle)
-		t.removeIdleConnLocked(oldest)
-	}
-
-	// Set idle timer, but only for HTTP/1 (pconn.alt == nil).
-	// The HTTP/2 implementation manages the idle timer itself
-	// (see idleConnTimeout in h2_bundle.go).
-	if t.IdleConnTimeout > 0 && pconn.alt == nil {
-		if pconn.idleTimer != nil {
-			pconn.idleTimer.Reset(t.IdleConnTimeout)
-		} else {
-			pconn.idleTimer = time.AfterFunc(t.IdleConnTimeout, pconn.closeConnIfStillIdle)
-		}
-	}
-	pconn.idleAt = time.Now()
-	return nil
-}
-
-// queueForIdleConn queues w to receive the next idle connection for w.cm.
-// As an optimization hint to the caller, queueForIdleConn reports whether
-// it successfully delivered an already-idle connection.
-func (t *Transport) queueForIdleConn(w *wantConn) (delivered bool) {
-	if t.DisableKeepAlives {
-		return false
-	}
-
-	t.idleMu.Lock()
-	defer t.idleMu.Unlock()
-
-	// Stop closing connections that become idle - we might want one.
-	// (That is, undo the effect of t.CloseIdleConnections.)
-	t.closeIdle = false
-
-	if w == nil {
-		// Happens in test hook.
-		return false
-	}
-
-	// If IdleConnTimeout is set, calculate the oldest
-	// persistConn.idleAt time we're willing to use a cached idle
-	// conn.
-	var oldTime time.Time
-	if t.IdleConnTimeout > 0 {
-		oldTime = time.Now().Add(-t.IdleConnTimeout)
-	}
-
-	// Look for most recently-used idle connection.
-	if list, ok := t.idleConn[w.key]; ok {
-		stop := false
-		delivered := false
-		for len(list) > 0 && !stop {
-			pconn := list[len(list)-1]
-
-			// See whether this connection has been idle too long, considering
-			// only the wall time (the Round(0)), in case this is a laptop or VM
-			// coming out of suspend with previously cached idle connections.
-			tooOld := !oldTime.IsZero() && pconn.idleAt.Round(0).Before(oldTime)
-			if tooOld {
-				// Async cleanup. Launch in its own goroutine (as if a
-				// time.AfterFunc called it); it acquires idleMu, which we're
-				// holding, and does a synchronous net.Conn.Close.
-				go pconn.closeConnIfStillIdle()
-			}
-			if pconn.isBroken() || tooOld {
-				// If either persistConn.readLoop has marked the connection
-				// broken, but Transport.removeIdleConn has not yet removed it
-				// from the idle list, or if this persistConn is too old (it was
-				// idle too long), then ignore it and look for another. In both
-				// cases it's already in the process of being closed.
-				list = list[:len(list)-1]
-				continue
-			}
-			delivered = w.tryDeliver(pconn, nil)
-			if delivered {
-				if pconn.alt != nil {
-					// HTTP/2: multiple clients can share pconn.
-					// Leave it in the list.
-				} else {
-					// HTTP/1: only one client can use pconn.
-					// Remove it from the list.
-					t.idleLRU.remove(pconn)
-					list = list[:len(list)-1]
-				}
-			}
-			stop = true
-		}
-		if len(list) > 0 {
-			t.idleConn[w.key] = list
-		} else {
-			delete(t.idleConn, w.key)
-		}
-		if stop {
-			return delivered
-		}
-	}
-
-	// Register to receive next connection that becomes idle.
-	if t.idleConnWait == nil {
-		t.idleConnWait = make(map[connectMethodKey]wantConnQueue)
-	}
-	q := t.idleConnWait[w.key]
-	q.cleanFront()
-	q.pushBack(w)
-	t.idleConnWait[w.key] = q
-	return false
-}
-
-// removeIdleConn marks pconn as dead.
-func (t *Transport) removeIdleConn(pconn *persistConn) bool {
-	t.idleMu.Lock()
-	defer t.idleMu.Unlock()
-	return t.removeIdleConnLocked(pconn)
-}
-
-// t.idleMu must be held.
-func (t *Transport) removeIdleConnLocked(pconn *persistConn) bool {
-	if pconn.idleTimer != nil {
-		pconn.idleTimer.Stop()
-	}
-	t.idleLRU.remove(pconn)
-	key := pconn.cacheKey
-	pconns := t.idleConn[key]
-	var removed bool
-	switch len(pconns) {
-	case 0:
-		// Nothing
-	case 1:
-		if pconns[0] == pconn {
-			delete(t.idleConn, key)
-			removed = true
-		}
-	default:
-		for i, v := range pconns {
-			if v != pconn {
-				continue
-			}
-			// Slide down, keeping most recently-used
-			// conns at the end.
-			copy(pconns[i:], pconns[i+1:])
-			t.idleConn[key] = pconns[:len(pconns)-1]
-			removed = true
-			break
-		}
-	}
-	return removed
-}
-
-func (t *Transport) setReqCanceler(key cancelKey, fn func(error)) {
-	t.reqMu.Lock()
-	defer t.reqMu.Unlock()
-	if t.reqCanceler == nil {
-		t.reqCanceler = make(map[cancelKey]func(error))
-	}
-	if fn != nil {
-		t.reqCanceler[key] = fn
-	} else {
-		delete(t.reqCanceler, key)
-	}
-}
-
-// replaceReqCanceler replaces an existing cancel function. If there is no cancel function
-// for the request, we don't set the function and return false.
-// Since CancelRequest will clear the canceler, we can use the return value to detect if
-// the request was canceled since the last setReqCancel call.
-func (t *Transport) replaceReqCanceler(key cancelKey, fn func(error)) bool {
-	t.reqMu.Lock()
-	defer t.reqMu.Unlock()
-	_, ok := t.reqCanceler[key]
-	if !ok {
-		return false
-	}
-	if fn != nil {
-		t.reqCanceler[key] = fn
-	} else {
-		delete(t.reqCanceler, key)
-	}
-	return true
-}
-
-var zeroDialer net.Dialer
-
-func (t *Transport) dial(ctx context.Context, network, addr string) (net.Conn, error) {
-	if t.DialContext != nil {
-		return t.DialContext(ctx, network, addr)
-	}
-	if t.Dial != nil {
-		c, err := t.Dial(network, addr)
-		if c == nil && err == nil {
-			err = errors.New("net/http: Transport.Dial hook returned (nil, nil)")
-		}
-		return c, err
-	}
-	return zeroDialer.DialContext(ctx, network, addr)
-}
-
-// A wantConn records state about a wanted connection
-// (that is, an active call to getConn).
-// The conn may be gotten by dialing or by finding an idle connection,
-// or a cancellation may make the conn no longer wanted.
-// These three options are racing against each other and use
-// wantConn to coordinate and agree about the winning outcome.
-type wantConn struct {
-	cm    connectMethod
-	key   connectMethodKey // cm.key()
-	ctx   context.Context  // context for dial
-	ready chan struct{}    // closed when pc, err pair is delivered
-
-	// hooks for testing to know when dials are done
-	// beforeDial is called in the getConn goroutine when the dial is queued.
-	// afterDial is called when the dial is completed or canceled.
-	beforeDial func()
-	afterDial  func()
-
-	mu  sync.Mutex // protects pc, err, close(ready)
-	pc  *persistConn
-	err error
-}
-
-// waiting reports whether w is still waiting for an answer (connection or error).
-func (w *wantConn) waiting() bool {
-	select {
-	case <-w.ready:
-		return false
-	default:
-		return true
-	}
-}
-
-// tryDeliver attempts to deliver pc, err to w and reports whether it succeeded.
-func (w *wantConn) tryDeliver(pc *persistConn, err error) bool {
-	w.mu.Lock()
-	defer w.mu.Unlock()
-
-	if w.pc != nil || w.err != nil {
-		return false
-	}
-
-	w.pc = pc
-	w.err = err
-	if w.pc == nil && w.err == nil {
-		panic("net/http: internal error: misuse of tryDeliver")
-	}
-	close(w.ready)
-	return true
-}
-
-// cancel marks w as no longer wanting a result (for example, due to cancellation).
-// If a connection has been delivered already, cancel returns it with t.putOrCloseIdleConn.
-func (w *wantConn) cancel(t *Transport, err error) {
-	w.mu.Lock()
-	if w.pc == nil && w.err == nil {
-		close(w.ready) // catch misbehavior in future delivery
-	}
-	pc := w.pc
-	w.pc = nil
-	w.err = err
-	w.mu.Unlock()
-
-	if pc != nil {
-		t.putOrCloseIdleConn(pc)
-	}
-}
-
-// A wantConnQueue is a queue of wantConns.
-type wantConnQueue struct {
-	// This is a queue, not a deque.
-	// It is split into two stages - head[headPos:] and tail.
-	// popFront is trivial (headPos++) on the first stage, and
-	// pushBack is trivial (append) on the second stage.
-	// If the first stage is empty, popFront can swap the
-	// first and second stages to remedy the situation.
-	//
-	// This two-stage split is analogous to the use of two lists
-	// in Okasaki's purely functional queue but without the
-	// overhead of reversing the list when swapping stages.
-	head    []*wantConn
-	headPos int
-	tail    []*wantConn
-}
-
-// len returns the number of items in the queue.
-func (q *wantConnQueue) len() int {
-	return len(q.head) - q.headPos + len(q.tail)
-}
-
-// pushBack adds w to the back of the queue.
-func (q *wantConnQueue) pushBack(w *wantConn) {
-	q.tail = append(q.tail, w)
-}
-
-// popFront removes and returns the wantConn at the front of the queue.
-func (q *wantConnQueue) popFront() *wantConn {
-	if q.headPos >= len(q.head) {
-		if len(q.tail) == 0 {
-			return nil
-		}
-		// Pick up tail as new head, clear tail.
-		q.head, q.headPos, q.tail = q.tail, 0, q.head[:0]
-	}
-	w := q.head[q.headPos]
-	q.head[q.headPos] = nil
-	q.headPos++
-	return w
-}
-
-// peekFront returns the wantConn at the front of the queue without removing it.
-func (q *wantConnQueue) peekFront() *wantConn {
-	if q.headPos < len(q.head) {
-		return q.head[q.headPos]
-	}
-	if len(q.tail) > 0 {
-		return q.tail[0]
-	}
-	return nil
-}
-
-// cleanFront pops any wantConns that are no longer waiting from the head of the
-// queue, reporting whether any were popped.
-func (q *wantConnQueue) cleanFront() (cleaned bool) {
-	for {
-		w := q.peekFront()
-		if w == nil || w.waiting() {
-			return cleaned
-		}
-		q.popFront()
-		cleaned = true
-	}
-}
-
-func (t *Transport) customDialTLS(ctx context.Context, network, addr string) (conn net.Conn, err error) {
-	if t.DialTLSContext != nil {
-		conn, err = t.DialTLSContext(ctx, network, addr)
-	} else {
-		conn, err = t.DialTLS(network, addr)
-	}
-	if conn == nil && err == nil {
-		err = errors.New("net/http: Transport.DialTLS or DialTLSContext returned (nil, nil)")
-	}
-	return
-}
-
-// getConn dials and creates a new persistConn to the target as
-// specified in the connectMethod. This includes doing a proxy CONNECT
-// and/or setting up TLS.  If this doesn't return an error, the persistConn
-// is ready to write requests to.
-func (t *Transport) getConn(treq *transportRequest, cm connectMethod) (pc *persistConn, err error) {
-	req := treq.Request
-	trace := treq.trace
-	ctx := req.Context()
-	if trace != nil && trace.GetConn != nil {
-		trace.GetConn(cm.addr())
-	}
-
-	w := &wantConn{
-		cm:         cm,
-		key:        cm.key(),
-		ctx:        ctx,
-		ready:      make(chan struct{}, 1),
-		beforeDial: testHookPrePendingDial,
-		afterDial:  testHookPostPendingDial,
-	}
-	defer func() {
-		if err != nil {
-			w.cancel(t, err)
-		}
-	}()
-
-	// Queue for idle connection.
-	if delivered := t.queueForIdleConn(w); delivered {
-		pc := w.pc
-		// Trace only for HTTP/1.
-		// HTTP/2 calls trace.GotConn itself.
-		if pc.alt == nil && trace != nil && trace.GotConn != nil {
-			trace.GotConn(pc.gotIdleConnTrace(pc.idleAt))
-		}
-		// set request canceler to some non-nil function so we
-		// can detect whether it was cleared between now and when
-		// we enter roundTrip
-		t.setReqCanceler(treq.cancelKey, func(error) {})
-		return pc, nil
-	}
-
-	cancelc := make(chan error, 1)
-	t.setReqCanceler(treq.cancelKey, func(err error) { cancelc <- err })
-
-	// Queue for permission to dial.
-	t.queueForDial(w)
-
-	// Wait for completion or cancellation.
-	select {
-	case <-w.ready:
-		// Trace success but only for HTTP/1.
-		// HTTP/2 calls trace.GotConn itself.
-		if w.pc != nil && w.pc.alt == nil && trace != nil && trace.GotConn != nil {
-			trace.GotConn(httptrace.GotConnInfo{Conn: w.pc.conn, Reused: w.pc.isReused()})
-		}
-		if w.err != nil {
-			// If the request has been canceled, that's probably
-			// what caused w.err; if so, prefer to return the
-			// cancellation error (see golang.org/issue/16049).
-			select {
-			case <-req.Cancel:
-				return nil, errRequestCanceledConn
-			case <-req.Context().Done():
-				return nil, req.Context().Err()
-			case err := <-cancelc:
-				if err == errRequestCanceled {
-					err = errRequestCanceledConn
-				}
-				return nil, err
-			default:
-				// return below
-			}
-		}
-		return w.pc, w.err
-	case <-req.Cancel:
-		return nil, errRequestCanceledConn
-	case <-req.Context().Done():
-		return nil, req.Context().Err()
-	case err := <-cancelc:
-		if err == errRequestCanceled {
-			err = errRequestCanceledConn
-		}
-		return nil, err
-	}
-}
-
-// queueForDial queues w to wait for permission to begin dialing.
-// Once w receives permission to dial, it will do so in a separate goroutine.
-func (t *Transport) queueForDial(w *wantConn) {
-	w.beforeDial()
-	if t.MaxConnsPerHost <= 0 {
-		go t.dialConnFor(w)
-		return
-	}
-
-	t.connsPerHostMu.Lock()
-	defer t.connsPerHostMu.Unlock()
-
-	if n := t.connsPerHost[w.key]; n < t.MaxConnsPerHost {
-		if t.connsPerHost == nil {
-			t.connsPerHost = make(map[connectMethodKey]int)
-		}
-		t.connsPerHost[w.key] = n + 1
-		go t.dialConnFor(w)
-		return
-	}
-
-	if t.connsPerHostWait == nil {
-		t.connsPerHostWait = make(map[connectMethodKey]wantConnQueue)
-	}
-	q := t.connsPerHostWait[w.key]
-	q.cleanFront()
-	q.pushBack(w)
-	t.connsPerHostWait[w.key] = q
-}
-
-// dialConnFor dials on behalf of w and delivers the result to w.
-// dialConnFor has received permission to dial w.cm and is counted in t.connCount[w.cm.key()].
-// If the dial is canceled or unsuccessful, dialConnFor decrements t.connCount[w.cm.key()].
-func (t *Transport) dialConnFor(w *wantConn) {
-	defer w.afterDial()
-
-	pc, err := t.dialConn(w.ctx, w.cm)
-	delivered := w.tryDeliver(pc, err)
-	if err == nil && (!delivered || pc.alt != nil) {
-		// pconn was not passed to w,
-		// or it is HTTP/2 and can be shared.
-		// Add to the idle connection pool.
-		t.putOrCloseIdleConn(pc)
-	}
-	if err != nil {
-		t.decConnsPerHost(w.key)
-	}
-}
-
-// decConnsPerHost decrements the per-host connection count for key,
-// which may in turn give a different waiting goroutine permission to dial.
-func (t *Transport) decConnsPerHost(key connectMethodKey) {
-	if t.MaxConnsPerHost <= 0 {
-		return
-	}
-
-	t.connsPerHostMu.Lock()
-	defer t.connsPerHostMu.Unlock()
-	n := t.connsPerHost[key]
-	if n == 0 {
-		// Shouldn't happen, but if it does, the counting is buggy and could
-		// easily lead to a silent deadlock, so report the problem loudly.
-		panic("net/http: internal error: connCount underflow")
-	}
-
-	// Can we hand this count to a goroutine still waiting to dial?
-	// (Some goroutines on the wait list may have timed out or
-	// gotten a connection another way. If they're all gone,
-	// we don't want to kick off any spurious dial operations.)
-	if q := t.connsPerHostWait[key]; q.len() > 0 {
-		done := false
-		for q.len() > 0 {
-			w := q.popFront()
-			if w.waiting() {
-				go t.dialConnFor(w)
-				done = true
-				break
-			}
-		}
-		if q.len() == 0 {
-			delete(t.connsPerHostWait, key)
-		} else {
-			// q is a value (like a slice), so we have to store
-			// the updated q back into the map.
-			t.connsPerHostWait[key] = q
-		}
-		if done {
-			return
-		}
-	}
-
-	// Otherwise, decrement the recorded count.
-	if n--; n == 0 {
-		delete(t.connsPerHost, key)
-	} else {
-		t.connsPerHost[key] = n
-	}
-}
-
-// Add TLS to a persistent connection, i.e. negotiate a TLS session. If pconn is already a TLS
-// tunnel, this function establishes a nested TLS session inside the encrypted channel.
-// The remote endpoint's name may be overridden by TLSClientConfig.ServerName.
-func (pconn *persistConn) addTLS(ctx context.Context, name string, trace *httptrace.ClientTrace) error {
-	// Initiate TLS and check remote host name against certificate.
-	cfg := cloneTLSConfig(pconn.t.TLSClientConfig)
-	if cfg.ServerName == "" {
-		cfg.ServerName = name
-	}
-	if pconn.cacheKey.onlyH1 {
-		cfg.NextProtos = nil
-	}
-	plainConn := pconn.conn
-	tlsConn := tls.Client(plainConn, cfg)
-	errc := make(chan error, 2)
-	var timer *time.Timer // for canceling TLS handshake
-	if d := pconn.t.TLSHandshakeTimeout; d != 0 {
-		timer = time.AfterFunc(d, func() {
-			errc <- tlsHandshakeTimeoutError{}
-		})
-	}
-	go func() {
-		if trace != nil && trace.TLSHandshakeStart != nil {
-			trace.TLSHandshakeStart()
-		}
-		err := tlsConn.HandshakeContext(ctx)
-		if timer != nil {
-			timer.Stop()
-		}
-		errc <- err
-	}()
-	if err := <-errc; err != nil {
-		plainConn.Close()
-		if trace != nil && trace.TLSHandshakeDone != nil {
-			trace.TLSHandshakeDone(tls.ConnectionState{}, err)
-		}
-		return err
-	}
-	cs := tlsConn.ConnectionState()
-	if trace != nil && trace.TLSHandshakeDone != nil {
-		trace.TLSHandshakeDone(cs, nil)
-	}
-	pconn.tlsState = &cs
-	pconn.conn = tlsConn
-	return nil
-}
-
-type erringRoundTripper interface {
-	RoundTripErr() error
-}
-
-func (t *Transport) dialConn(ctx context.Context, cm connectMethod) (pconn *persistConn, err error) {
-	pconn = &persistConn{
-		t:             t,
-		cacheKey:      cm.key(),
-		reqch:         make(chan requestAndChan, 1),
-		writech:       make(chan writeRequest, 1),
-		closech:       make(chan struct{}),
-		writeErrCh:    make(chan error, 1),
-		writeLoopDone: make(chan struct{}),
-	}
-	trace := httptrace.ContextClientTrace(ctx)
-	wrapErr := func(err error) error {
-		if cm.proxyURL != nil {
-			// Return a typed error, per Issue 16997
-			return &net.OpError{Op: "proxyconnect", Net: "tcp", Err: err}
-		}
-		return err
-	}
-	if cm.scheme() == "https" && t.hasCustomTLSDialer() {
-		var err error
-		pconn.conn, err = t.customDialTLS(ctx, "tcp", cm.addr())
-		if err != nil {
-			return nil, wrapErr(err)
-		}
-		if tc, ok := pconn.conn.(*tls.Conn); ok {
-			// Handshake here, in case DialTLS didn't. TLSNextProto below
-			// depends on it for knowing the connection state.
-			if trace != nil && trace.TLSHandshakeStart != nil {
-				trace.TLSHandshakeStart()
-			}
-			if err := tc.HandshakeContext(ctx); err != nil {
-				go pconn.conn.Close()
-				if trace != nil && trace.TLSHandshakeDone != nil {
-					trace.TLSHandshakeDone(tls.ConnectionState{}, err)
-				}
-				return nil, err
-			}
-			cs := tc.ConnectionState()
-			if trace != nil && trace.TLSHandshakeDone != nil {
-				trace.TLSHandshakeDone(cs, nil)
-			}
-			pconn.tlsState = &cs
-		}
-	} else {
-		conn, err := t.dial(ctx, "tcp", cm.addr())
-		if err != nil {
-			return nil, wrapErr(err)
-		}
-		pconn.conn = conn
-		if cm.scheme() == "https" {
-			var firstTLSHost string
-			if firstTLSHost, _, err = net.SplitHostPort(cm.addr()); err != nil {
-				return nil, wrapErr(err)
-			}
-			if err = pconn.addTLS(ctx, firstTLSHost, trace); err != nil {
-				return nil, wrapErr(err)
-			}
-		}
-	}
-
-	// Proxy setup.
-	switch {
-	case cm.proxyURL == nil:
-		// Do nothing. Not using a proxy.
-	case cm.proxyURL.Scheme == "socks5":
-		conn := pconn.conn
-		d := socksNewDialer("tcp", conn.RemoteAddr().String())
-		if u := cm.proxyURL.User; u != nil {
-			auth := &socksUsernamePassword{
-				Username: u.Username(),
-			}
-			auth.Password, _ = u.Password()
-			d.AuthMethods = []socksAuthMethod{
-				socksAuthMethodNotRequired,
-				socksAuthMethodUsernamePassword,
-			}
-			d.Authenticate = auth.Authenticate
-		}
-		if _, err := d.DialWithConn(ctx, conn, "tcp", cm.targetAddr); err != nil {
-			conn.Close()
-			return nil, err
-		}
-	case cm.targetScheme == "http":
-		pconn.isProxy = true
-		if pa := cm.proxyAuth(); pa != "" {
-			pconn.mutateHeaderFunc = func(h Header) {
-				h.Set("Proxy-Authorization", pa)
-			}
-		}
-	case cm.targetScheme == "https":
-		conn := pconn.conn
-		var hdr Header
-		if t.GetProxyConnectHeader != nil {
-			var err error
-			hdr, err = t.GetProxyConnectHeader(ctx, cm.proxyURL, cm.targetAddr)
-			if err != nil {
-				conn.Close()
-				return nil, err
-			}
-		} else {
-			hdr = t.ProxyConnectHeader
-		}
-		if hdr == nil {
-			hdr = make(Header)
-		}
-		if pa := cm.proxyAuth(); pa != "" {
-			hdr = hdr.Clone()
-			hdr.Set("Proxy-Authorization", pa)
-		}
-		connectReq := &Request{
-			Method: "CONNECT",
-			URL:    &url.URL{Opaque: cm.targetAddr},
-			Host:   cm.targetAddr,
-			Header: hdr,
-		}
-
-		// If there's no done channel (no deadline or cancellation
-		// from the caller possible), at least set some (long)
-		// timeout here. This will make sure we don't block forever
-		// and leak a goroutine if the connection stops replying
-		// after the TCP connect.
-		connectCtx := ctx
-		if ctx.Done() == nil {
-			newCtx, cancel := context.WithTimeout(ctx, 1*time.Minute)
-			defer cancel()
-			connectCtx = newCtx
-		}
-
-		didReadResponse := make(chan struct{}) // closed after CONNECT write+read is done or fails
-		var (
-			resp *Response
-			err  error // write or read error
-		)
-		// Write the CONNECT request & read the response.
-		go func() {
-			defer close(didReadResponse)
-			err = connectReq.Write(conn)
-			if err != nil {
-				return
-			}
-			// Okay to use and discard buffered reader here, because
-			// TLS server will not speak until spoken to.
-			br := bufio.NewReader(conn)
-			resp, err = ReadResponse(br, connectReq)
-		}()
-		select {
-		case <-connectCtx.Done():
-			conn.Close()
-			<-didReadResponse
-			return nil, connectCtx.Err()
-		case <-didReadResponse:
-			// resp or err now set
-		}
-		if err != nil {
-			conn.Close()
-			return nil, err
-		}
-		if resp.StatusCode != 200 {
-			_, text, ok := strings.Cut(resp.Status, " ")
-			conn.Close()
-			if !ok {
-				return nil, errors.New("unknown status code")
-			}
-			return nil, errors.New(text)
-		}
-	}
-
-	if cm.proxyURL != nil && cm.targetScheme == "https" {
-		if err := pconn.addTLS(ctx, cm.tlsHost(), trace); err != nil {
-			return nil, err
-		}
-	}
-
-	if s := pconn.tlsState; s != nil && s.NegotiatedProtocolIsMutual && s.NegotiatedProtocol != "" {
-		if next, ok := t.TLSNextProto[s.NegotiatedProtocol]; ok {
-			alt := next(cm.targetAddr, pconn.conn.(*tls.Conn))
-			if e, ok := alt.(erringRoundTripper); ok {
-				// pconn.conn was closed by next (http2configureTransports.upgradeFn).
-				return nil, e.RoundTripErr()
-			}
-			return &persistConn{t: t, cacheKey: pconn.cacheKey, alt: alt}, nil
-		}
-	}
-
-	pconn.br = bufio.NewReaderSize(pconn, t.readBufferSize())
-	pconn.bw = bufio.NewWriterSize(persistConnWriter{pconn}, t.writeBufferSize())
-
-	go pconn.readLoop()
-	go pconn.writeLoop()
-	return pconn, nil
-}
-
-// persistConnWriter is the io.Writer written to by pc.bw.
-// It accumulates the number of bytes written to the underlying conn,
-// so the retry logic can determine whether any bytes made it across
-// the wire.
-// This is exactly 1 pointer field wide so it can go into an interface
-// without allocation.
-type persistConnWriter struct {
-	pc *persistConn
-}
-
-func (w persistConnWriter) Write(p []byte) (n int, err error) {
-	n, err = w.pc.conn.Write(p)
-	w.pc.nwrite += int64(n)
-	return
-}
-
-// ReadFrom exposes persistConnWriter's underlying Conn to io.Copy and if
-// the Conn implements io.ReaderFrom, it can take advantage of optimizations
-// such as sendfile.
-func (w persistConnWriter) ReadFrom(r io.Reader) (n int64, err error) {
-	n, err = io.Copy(w.pc.conn, r)
-	w.pc.nwrite += n
-	return
-}
-
-var _ io.ReaderFrom = (*persistConnWriter)(nil)
-
-// connectMethod is the map key (in its String form) for keeping persistent
-// TCP connections alive for subsequent HTTP requests.
-//
-// A connect method may be of the following types:
-//
-//	connectMethod.key().String()      Description
-//	------------------------------    -------------------------
-//	|http|foo.com                     http directly to server, no proxy
-//	|https|foo.com                    https directly to server, no proxy
-//	|https,h1|foo.com                 https directly to server w/o HTTP/2, no proxy
-//	http://proxy.com|https|foo.com    http to proxy, then CONNECT to foo.com
-//	http://proxy.com|http             http to proxy, http to anywhere after that
-//	socks5://proxy.com|http|foo.com   socks5 to proxy, then http to foo.com
-//	socks5://proxy.com|https|foo.com  socks5 to proxy, then https to foo.com
-//	https://proxy.com|https|foo.com   https to proxy, then CONNECT to foo.com
-//	https://proxy.com|http            https to proxy, http to anywhere after that
-//
-type connectMethod struct {
-	_            incomparable
-	proxyURL     *url.URL // nil for no proxy, else full proxy URL
-	targetScheme string   // "http" or "https"
-	// If proxyURL specifies an http or https proxy, and targetScheme is http (not https),
-	// then targetAddr is not included in the connect method key, because the socket can
-	// be reused for different targetAddr values.
-	targetAddr string
-	onlyH1     bool // whether to disable HTTP/2 and force HTTP/1
-}
-
-func (cm *connectMethod) key() connectMethodKey {
-	proxyStr := ""
-	targetAddr := cm.targetAddr
-	if cm.proxyURL != nil {
-		proxyStr = cm.proxyURL.String()
-		if (cm.proxyURL.Scheme == "http" || cm.proxyURL.Scheme == "https") && cm.targetScheme == "http" {
-			targetAddr = ""
-		}
-	}
-	return connectMethodKey{
-		proxy:  proxyStr,
-		scheme: cm.targetScheme,
-		addr:   targetAddr,
-		onlyH1: cm.onlyH1,
-	}
-}
-
-// scheme returns the first hop scheme: http, https, or socks5
-func (cm *connectMethod) scheme() string {
-	if cm.proxyURL != nil {
-		return cm.proxyURL.Scheme
-	}
-	return cm.targetScheme
-}
-
-// addr returns the first hop "host:port" to which we need to TCP connect.
-func (cm *connectMethod) addr() string {
-	if cm.proxyURL != nil {
-		return canonicalAddr(cm.proxyURL)
-	}
-	return cm.targetAddr
-}
-
-// tlsHost returns the host name to match against the peer's
-// TLS certificate.
-func (cm *connectMethod) tlsHost() string {
-	h := cm.targetAddr
-	if hasPort(h) {
-		h = h[:strings.LastIndex(h, ":")]
-	}
-	return h
-}
-
-// connectMethodKey is the map key version of connectMethod, with a
-// stringified proxy URL (or the empty string) instead of a pointer to
-// a URL.
-type connectMethodKey struct {
-	proxy, scheme, addr string
-	onlyH1              bool
-}
-
-func (k connectMethodKey) String() string {
-	// Only used by tests.
-	var h1 string
-	if k.onlyH1 {
-		h1 = ",h1"
-	}
-	return fmt.Sprintf("%s|%s%s|%s", k.proxy, k.scheme, h1, k.addr)
-}
-
-// persistConn wraps a connection, usually a persistent one
-// (but may be used for non-keep-alive requests as well)
-type persistConn struct {
-	// alt optionally specifies the TLS NextProto RoundTripper.
-	// This is used for HTTP/2 today and future protocols later.
-	// If it's non-nil, the rest of the fields are unused.
-	alt RoundTripper
-
-	t         *Transport
-	cacheKey  connectMethodKey
-	conn      net.Conn
-	tlsState  *tls.ConnectionState
-	br        *bufio.Reader       // from conn
-	bw        *bufio.Writer       // to conn
-	nwrite    int64               // bytes written
-	reqch     chan requestAndChan // written by roundTrip; read by readLoop
-	writech   chan writeRequest   // written by roundTrip; read by writeLoop
-	closech   chan struct{}       // closed when conn closed
-	isProxy   bool
-	sawEOF    bool  // whether we've seen EOF from conn; owned by readLoop
-	readLimit int64 // bytes allowed to be read; owned by readLoop
-	// writeErrCh passes the request write error (usually nil)
-	// from the writeLoop goroutine to the readLoop which passes
-	// it off to the res.Body reader, which then uses it to decide
-	// whether or not a connection can be reused. Issue 7569.
-	writeErrCh chan error
-
-	writeLoopDone chan struct{} // closed when write loop ends
-
-	// Both guarded by Transport.idleMu:
-	idleAt    time.Time   // time it last become idle
-	idleTimer *time.Timer // holding an AfterFunc to close it
-
-	mu                   sync.Mutex // guards following fields
-	numExpectedResponses int
-	closed               error // set non-nil when conn is closed, before closech is closed
-	canceledErr          error // set non-nil if conn is canceled
-	broken               bool  // an error has happened on this connection; marked broken so it's not reused.
-	reused               bool  // whether conn has had successful request/response and is being reused.
-	// mutateHeaderFunc is an optional func to modify extra
-	// headers on each outbound request before it's written. (the
-	// original Request given to RoundTrip is not modified)
-	mutateHeaderFunc func(Header)
-}
-
-func (pc *persistConn) maxHeaderResponseSize() int64 {
-	if v := pc.t.MaxResponseHeaderBytes; v != 0 {
-		return v
-	}
-	return 10 << 20 // conservative default; same as http2
-}
-
-func (pc *persistConn) Read(p []byte) (n int, err error) {
-	if pc.readLimit <= 0 {
-		return 0, fmt.Errorf("read limit of %d bytes exhausted", pc.maxHeaderResponseSize())
-	}
-	if int64(len(p)) > pc.readLimit {
-		p = p[:pc.readLimit]
-	}
-	n, err = pc.conn.Read(p)
-	if err == io.EOF {
-		pc.sawEOF = true
-	}
-	pc.readLimit -= int64(n)
-	return
-}
-
-// isBroken reports whether this connection is in a known broken state.
-func (pc *persistConn) isBroken() bool {
-	pc.mu.Lock()
-	b := pc.closed != nil
-	pc.mu.Unlock()
-	return b
-}
-
-// canceled returns non-nil if the connection was closed due to
-// CancelRequest or due to context cancellation.
-func (pc *persistConn) canceled() error {
-	pc.mu.Lock()
-	defer pc.mu.Unlock()
-	return pc.canceledErr
-}
-
-// isReused reports whether this connection has been used before.
-func (pc *persistConn) isReused() bool {
-	pc.mu.Lock()
-	r := pc.reused
-	pc.mu.Unlock()
-	return r
-}
-
-func (pc *persistConn) gotIdleConnTrace(idleAt time.Time) (t httptrace.GotConnInfo) {
-	pc.mu.Lock()
-	defer pc.mu.Unlock()
-	t.Reused = pc.reused
-	t.Conn = pc.conn
-	t.WasIdle = true
-	if !idleAt.IsZero() {
-		t.IdleTime = time.Since(idleAt)
-	}
-	return
-}
-
-func (pc *persistConn) cancelRequest(err error) {
-	pc.mu.Lock()
-	defer pc.mu.Unlock()
-	pc.canceledErr = err
-	pc.closeLocked(errRequestCanceled)
-}
-
-// closeConnIfStillIdle closes the connection if it's still sitting idle.
-// This is what's called by the persistConn's idleTimer, and is run in its
-// own goroutine.
-func (pc *persistConn) closeConnIfStillIdle() {
-	t := pc.t
-	t.idleMu.Lock()
-	defer t.idleMu.Unlock()
-	if _, ok := t.idleLRU.m[pc]; !ok {
-		// Not idle.
-		return
-	}
-	t.removeIdleConnLocked(pc)
-	pc.close(errIdleConnTimeout)
-}
-
-// mapRoundTripError returns the appropriate error value for
-// persistConn.roundTrip.
-//
-// The provided err is the first error that (*persistConn).roundTrip
-// happened to receive from its select statement.
-//
-// The startBytesWritten value should be the value of pc.nwrite before the roundTrip
-// started writing the request.
-func (pc *persistConn) mapRoundTripError(req *transportRequest, startBytesWritten int64, err error) error {
-	if err == nil {
-		return nil
-	}
-
-	// Wait for the writeLoop goroutine to terminate to avoid data
-	// races on callers who mutate the request on failure.
-	//
-	// When resc in pc.roundTrip and hence rc.ch receives a responseAndError
-	// with a non-nil error it implies that the persistConn is either closed
-	// or closing. Waiting on pc.writeLoopDone is hence safe as all callers
-	// close closech which in turn ensures writeLoop returns.
-	<-pc.writeLoopDone
-
-	// If the request was canceled, that's better than network
-	// failures that were likely the result of tearing down the
-	// connection.
-	if cerr := pc.canceled(); cerr != nil {
-		return cerr
-	}
-
-	// See if an error was set explicitly.
-	req.mu.Lock()
-	reqErr := req.err
-	req.mu.Unlock()
-	if reqErr != nil {
-		return reqErr
-	}
-
-	if err == errServerClosedIdle {
-		// Don't decorate
-		return err
-	}
-
-	if _, ok := err.(transportReadFromServerError); ok {
-		if pc.nwrite == startBytesWritten {
-			return nothingWrittenError{err}
-		}
-		// Don't decorate
-		return err
-	}
-	if pc.isBroken() {
-		if pc.nwrite == startBytesWritten {
-			return nothingWrittenError{err}
-		}
-		return fmt.Errorf("net/http: HTTP/1.x transport connection broken: %v", err)
-	}
-	return err
-}
-
-// errCallerOwnsConn is an internal sentinel error used when we hand
-// off a writable response.Body to the caller. We use this to prevent
-// closing a net.Conn that is now owned by the caller.
-var errCallerOwnsConn = errors.New("read loop ending; caller owns writable underlying conn")
-
-func (pc *persistConn) readLoop() {
-	closeErr := errReadLoopExiting // default value, if not changed below
-	defer func() {
-		pc.close(closeErr)
-		pc.t.removeIdleConn(pc)
-	}()
-
-	tryPutIdleConn := func(trace *httptrace.ClientTrace) bool {
-		if err := pc.t.tryPutIdleConn(pc); err != nil {
-			closeErr = err
-			if trace != nil && trace.PutIdleConn != nil && err != errKeepAlivesDisabled {
-				trace.PutIdleConn(err)
-			}
-			return false
-		}
-		if trace != nil && trace.PutIdleConn != nil {
-			trace.PutIdleConn(nil)
-		}
-		return true
-	}
-
-	// eofc is used to block caller goroutines reading from Response.Body
-	// at EOF until this goroutines has (potentially) added the connection
-	// back to the idle pool.
-	eofc := make(chan struct{})
-	defer close(eofc) // unblock reader on errors
-
-	// Read this once, before loop starts. (to avoid races in tests)
-	testHookMu.Lock()
-	testHookReadLoopBeforeNextRead := testHookReadLoopBeforeNextRead
-	testHookMu.Unlock()
-
-	alive := true
-	for alive {
-		pc.readLimit = pc.maxHeaderResponseSize()
-		_, err := pc.br.Peek(1)
-
-		pc.mu.Lock()
-		if pc.numExpectedResponses == 0 {
-			pc.readLoopPeekFailLocked(err)
-			pc.mu.Unlock()
-			return
-		}
-		pc.mu.Unlock()
-
-		rc := <-pc.reqch
-		trace := httptrace.ContextClientTrace(rc.req.Context())
-
-		var resp *Response
-		if err == nil {
-			resp, err = pc.readResponse(rc, trace)
-		} else {
-			err = transportReadFromServerError{err}
-			closeErr = err
-		}
-
-		if err != nil {
-			if pc.readLimit <= 0 {
-				err = fmt.Errorf("net/http: server response headers exceeded %d bytes; aborted", pc.maxHeaderResponseSize())
-			}
-
-			select {
-			case rc.ch <- responseAndError{err: err}:
-			case <-rc.callerGone:
-				return
-			}
-			return
-		}
-		pc.readLimit = maxInt64 // effectively no limit for response bodies
-
-		pc.mu.Lock()
-		pc.numExpectedResponses--
-		pc.mu.Unlock()
-
-		bodyWritable := resp.bodyIsWritable()
-		hasBody := rc.req.Method != "HEAD" && resp.ContentLength != 0
-
-		if resp.Close || rc.req.Close || resp.StatusCode <= 199 || bodyWritable {
-			// Don't do keep-alive on error if either party requested a close
-			// or we get an unexpected informational (1xx) response.
-			// StatusCode 100 is already handled above.
-			alive = false
-		}
-
-		if !hasBody || bodyWritable {
-			replaced := pc.t.replaceReqCanceler(rc.cancelKey, nil)
-
-			// Put the idle conn back into the pool before we send the response
-			// so if they process it quickly and make another request, they'll
-			// get this same conn. But we use the unbuffered channel 'rc'
-			// to guarantee that persistConn.roundTrip got out of its select
-			// potentially waiting for this persistConn to close.
-			alive = alive &&
-				!pc.sawEOF &&
-				pc.wroteRequest() &&
-				replaced && tryPutIdleConn(trace)
-
-			if bodyWritable {
-				closeErr = errCallerOwnsConn
-			}
-
-			select {
-			case rc.ch <- responseAndError{res: resp}:
-			case <-rc.callerGone:
-				return
-			}
-
-			// Now that they've read from the unbuffered channel, they're safely
-			// out of the select that also waits on this goroutine to die, so
-			// we're allowed to exit now if needed (if alive is false)
-			testHookReadLoopBeforeNextRead()
-			continue
-		}
-
-		waitForBodyRead := make(chan bool, 2)
-		body := &bodyEOFSignal{
-			body: resp.Body,
-			earlyCloseFn: func() error {
-				waitForBodyRead <- false
-				<-eofc // will be closed by deferred call at the end of the function
-				return nil
-
-			},
-			fn: func(err error) error {
-				isEOF := err == io.EOF
-				waitForBodyRead <- isEOF
-				if isEOF {
-					<-eofc // see comment above eofc declaration
-				} else if err != nil {
-					if cerr := pc.canceled(); cerr != nil {
-						return cerr
-					}
-				}
-				return err
-			},
-		}
-
-		resp.Body = body
-		if rc.addedGzip && ascii.EqualFold(resp.Header.Get("Content-Encoding"), "gzip") {
-			resp.Body = &gzipReader{body: body}
-			resp.Header.Del("Content-Encoding")
-			resp.Header.Del("Content-Length")
-			resp.ContentLength = -1
-			resp.Uncompressed = true
-		}
-
-		select {
-		case rc.ch <- responseAndError{res: resp}:
-		case <-rc.callerGone:
-			return
-		}
-
-		// Before looping back to the top of this function and peeking on
-		// the bufio.Reader, wait for the caller goroutine to finish
-		// reading the response body. (or for cancellation or death)
-		select {
-		case bodyEOF := <-waitForBodyRead:
-			replaced := pc.t.replaceReqCanceler(rc.cancelKey, nil) // before pc might return to idle pool
-			alive = alive &&
-				bodyEOF &&
-				!pc.sawEOF &&
-				pc.wroteRequest() &&
-				replaced && tryPutIdleConn(trace)
-			if bodyEOF {
-				eofc <- struct{}{}
-			}
-		case <-rc.req.Cancel:
-			alive = false
-			pc.t.CancelRequest(rc.req)
-		case <-rc.req.Context().Done():
-			alive = false
-			pc.t.cancelRequest(rc.cancelKey, rc.req.Context().Err())
-		case <-pc.closech:
-			alive = false
-		}
-
-		testHookReadLoopBeforeNextRead()
-	}
-}
-
-func (pc *persistConn) readLoopPeekFailLocked(peekErr error) {
-	if pc.closed != nil {
-		return
-	}
-	if n := pc.br.Buffered(); n > 0 {
-		buf, _ := pc.br.Peek(n)
-		if is408Message(buf) {
-			pc.closeLocked(errServerClosedIdle)
-			return
-		} else {
-			log.Printf("Unsolicited response received on idle HTTP channel starting with %q; err=%v", buf, peekErr)
-		}
-	}
-	if peekErr == io.EOF {
-		// common case.
-		pc.closeLocked(errServerClosedIdle)
-	} else {
-		pc.closeLocked(fmt.Errorf("readLoopPeekFailLocked: %v", peekErr))
-	}
-}
-
-// is408Message reports whether buf has the prefix of an
-// HTTP 408 Request Timeout response.
-// See golang.org/issue/32310.
-func is408Message(buf []byte) bool {
-	if len(buf) < len("HTTP/1.x 408") {
-		return false
-	}
-	if string(buf[:7]) != "HTTP/1." {
-		return false
-	}
-	return string(buf[8:12]) == " 408"
-}
-
-// readResponse reads an HTTP response (or two, in the case of "Expect:
-// 100-continue") from the server. It returns the final non-100 one.
-// trace is optional.
-func (pc *persistConn) readResponse(rc requestAndChan, trace *httptrace.ClientTrace) (resp *Response, err error) {
-	if trace != nil && trace.GotFirstResponseByte != nil {
-		if peek, err := pc.br.Peek(1); err == nil && len(peek) == 1 {
-			trace.GotFirstResponseByte()
-		}
-	}
-	num1xx := 0               // number of informational 1xx headers received
-	const max1xxResponses = 5 // arbitrary bound on number of informational responses
-
-	continueCh := rc.continueCh
-	for {
-		resp, err = ReadResponse(pc.br, rc.req)
-		if err != nil {
-			return
-		}
-		resCode := resp.StatusCode
-		if continueCh != nil {
-			if resCode == 100 {
-				if trace != nil && trace.Got100Continue != nil {
-					trace.Got100Continue()
-				}
-				continueCh <- struct{}{}
-				continueCh = nil
-			} else if resCode >= 200 {
-				close(continueCh)
-				continueCh = nil
-			}
-		}
-		is1xx := 100 <= resCode && resCode <= 199
-		// treat 101 as a terminal status, see issue 26161
-		is1xxNonTerminal := is1xx && resCode != StatusSwitchingProtocols
-		if is1xxNonTerminal {
-			num1xx++
-			if num1xx > max1xxResponses {
-				return nil, errors.New("net/http: too many 1xx informational responses")
-			}
-			pc.readLimit = pc.maxHeaderResponseSize() // reset the limit
-			if trace != nil && trace.Got1xxResponse != nil {
-				if err := trace.Got1xxResponse(resCode, textproto.MIMEHeader(resp.Header)); err != nil {
-					return nil, err
-				}
-			}
-			continue
-		}
-		break
-	}
-	if resp.isProtocolSwitch() {
-		resp.Body = newReadWriteCloserBody(pc.br, pc.conn)
-	}
-
-	resp.TLS = pc.tlsState
-	return
-}
-
-// waitForContinue returns the function to block until
-// any response, timeout or connection close. After any of them,
-// the function returns a bool which indicates if the body should be sent.
-func (pc *persistConn) waitForContinue(continueCh <-chan struct{}) func() bool {
-	if continueCh == nil {
-		return nil
-	}
-	return func() bool {
-		timer := time.NewTimer(pc.t.ExpectContinueTimeout)
-		defer timer.Stop()
-
-		select {
-		case _, ok := <-continueCh:
-			return ok
-		case <-timer.C:
-			return true
-		case <-pc.closech:
-			return false
-		}
-	}
-}
-
-func newReadWriteCloserBody(br *bufio.Reader, rwc io.ReadWriteCloser) io.ReadWriteCloser {
-	body := &readWriteCloserBody{ReadWriteCloser: rwc}
-	if br.Buffered() != 0 {
-		body.br = br
-	}
-	return body
-}
-
-// readWriteCloserBody is the Response.Body type used when we want to
-// give users write access to the Body through the underlying
-// connection (TCP, unless using custom dialers). This is then
-// the concrete type for a Response.Body on the 101 Switching
-// Protocols response, as used by WebSockets, h2c, etc.
-type readWriteCloserBody struct {
-	_  incomparable
-	br *bufio.Reader // used until empty
-	io.ReadWriteCloser
-}
-
-func (b *readWriteCloserBody) Read(p []byte) (n int, err error) {
-	if b.br != nil {
-		if n := b.br.Buffered(); len(p) > n {
-			p = p[:n]
-		}
-		n, err = b.br.Read(p)
-		if b.br.Buffered() == 0 {
-			b.br = nil
-		}
-		return n, err
-	}
-	return b.ReadWriteCloser.Read(p)
-}
-
-// nothingWrittenError wraps a write errors which ended up writing zero bytes.
-type nothingWrittenError struct {
-	error
-}
-
-func (pc *persistConn) writeLoop() {
-	defer close(pc.writeLoopDone)
-	for {
-		select {
-		case wr := <-pc.writech:
-			startBytesWritten := pc.nwrite
-			err := wr.req.Request.write(pc.bw, pc.isProxy, wr.req.extra, pc.waitForContinue(wr.continueCh))
-			if bre, ok := err.(requestBodyReadError); ok {
-				err = bre.error
-				// Errors reading from the user's
-				// Request.Body are high priority.
-				// Set it here before sending on the
-				// channels below or calling
-				// pc.close() which tears down
-				// connections and causes other
-				// errors.
-				wr.req.setError(err)
-			}
-			if err == nil {
-				err = pc.bw.Flush()
-			}
-			if err != nil {
-				if pc.nwrite == startBytesWritten {
-					err = nothingWrittenError{err}
-				}
-			}
-			pc.writeErrCh <- err // to the body reader, which might recycle us
-			wr.ch <- err         // to the roundTrip function
-			if err != nil {
-				pc.close(err)
-				return
-			}
-		case <-pc.closech:
-			return
-		}
-	}
-}
-
-// maxWriteWaitBeforeConnReuse is how long the a Transport RoundTrip
-// will wait to see the Request's Body.Write result after getting a
-// response from the server. See comments in (*persistConn).wroteRequest.
-const maxWriteWaitBeforeConnReuse = 50 * time.Millisecond
-
-// wroteRequest is a check before recycling a connection that the previous write
-// (from writeLoop above) happened and was successful.
-func (pc *persistConn) wroteRequest() bool {
-	select {
-	case err := <-pc.writeErrCh:
-		// Common case: the write happened well before the response, so
-		// avoid creating a timer.
-		return err == nil
-	default:
-		// Rare case: the request was written in writeLoop above but
-		// before it could send to pc.writeErrCh, the reader read it
-		// all, processed it, and called us here. In this case, give the
-		// write goroutine a bit of time to finish its send.
-		//
-		// Less rare case: We also get here in the legitimate case of
-		// Issue 7569, where the writer is still writing (or stalled),
-		// but the server has already replied. In this case, we don't
-		// want to wait too long, and we want to return false so this
-		// connection isn't re-used.
-		t := time.NewTimer(maxWriteWaitBeforeConnReuse)
-		defer t.Stop()
-		select {
-		case err := <-pc.writeErrCh:
-			return err == nil
-		case <-t.C:
-			return false
-		}
-	}
-}
-
-// responseAndError is how the goroutine reading from an HTTP/1 server
-// communicates with the goroutine doing the RoundTrip.
-type responseAndError struct {
-	_   incomparable
-	res *Response // else use this response (see res method)
-	err error
-}
-
-type requestAndChan struct {
-	_         incomparable
-	req       *Request
-	cancelKey cancelKey
-	ch        chan responseAndError // unbuffered; always send in select on callerGone
-
-	// whether the Transport (as opposed to the user client code)
-	// added the Accept-Encoding gzip header. If the Transport
-	// set it, only then do we transparently decode the gzip.
-	addedGzip bool
-
-	// Optional blocking chan for Expect: 100-continue (for send).
-	// If the request has an "Expect: 100-continue" header and
-	// the server responds 100 Continue, readLoop send a value
-	// to writeLoop via this chan.
-	continueCh chan<- struct{}
-
-	callerGone <-chan struct{} // closed when roundTrip caller has returned
-}
-
-// A writeRequest is sent by the caller's goroutine to the
-// writeLoop's goroutine to write a request while the read loop
-// concurrently waits on both the write response and the server's
-// reply.
-type writeRequest struct {
-	req *transportRequest
-	ch  chan<- error
-
-	// Optional blocking chan for Expect: 100-continue (for receive).
-	// If not nil, writeLoop blocks sending request body until
-	// it receives from this chan.
-	continueCh <-chan struct{}
-}
-
-type httpError struct {
-	err     string
-	timeout bool
-}
-
-func (e *httpError) Error() string   { return e.err }
-func (e *httpError) Timeout() bool   { return e.timeout }
-func (e *httpError) Temporary() bool { return true }
-
-var errTimeout error = &httpError{err: "net/http: timeout awaiting response headers", timeout: true}
-
-// errRequestCanceled is set to be identical to the one from h2 to facilitate
-// testing.
-var errRequestCanceled = http2errRequestCanceled
-var errRequestCanceledConn = errors.New("net/http: request canceled while waiting for connection") // TODO: unify?
-
-func nop() {}
-
-// testHooks. Always non-nil.
-var (
-	testHookEnterRoundTrip   = nop
-	testHookWaitResLoop      = nop
-	testHookRoundTripRetried = nop
-	testHookPrePendingDial   = nop
-	testHookPostPendingDial  = nop
-
-	testHookMu                     sync.Locker = fakeLocker{} // guards following
-	testHookReadLoopBeforeNextRead             = nop
-)
-
-func (pc *persistConn) roundTrip(req *transportRequest) (resp *Response, err error) {
-	testHookEnterRoundTrip()
-	if !pc.t.replaceReqCanceler(req.cancelKey, pc.cancelRequest) {
-		pc.t.putOrCloseIdleConn(pc)
-		return nil, errRequestCanceled
-	}
-	pc.mu.Lock()
-	pc.numExpectedResponses++
-	headerFn := pc.mutateHeaderFunc
-	pc.mu.Unlock()
-
-	if headerFn != nil {
-		headerFn(req.extraHeaders())
-	}
-
-	// Ask for a compressed version if the caller didn't set their
-	// own value for Accept-Encoding. We only attempt to
-	// uncompress the gzip stream if we were the layer that
-	// requested it.
-	requestedGzip := false
-	if !pc.t.DisableCompression &&
-		req.Header.Get("Accept-Encoding") == "" &&
-		req.Header.Get("Range") == "" &&
-		req.Method != "HEAD" {
-		// Request gzip only, not deflate. Deflate is ambiguous and
-		// not as universally supported anyway.
-		// See: https://zlib.net/zlib_faq.html#faq39
-		//
-		// Note that we don't request this for HEAD requests,
-		// due to a bug in nginx:
-		//   https://trac.nginx.org/nginx/ticket/358
-		//   https://golang.org/issue/5522
-		//
-		// We don't request gzip if the request is for a range, since
-		// auto-decoding a portion of a gzipped document will just fail
-		// anyway. See https://golang.org/issue/8923
-		requestedGzip = true
-		req.extraHeaders().Set("Accept-Encoding", "gzip")
-	}
-
-	var continueCh chan struct{}
-	if req.ProtoAtLeast(1, 1) && req.Body != nil && req.expectsContinue() {
-		continueCh = make(chan struct{}, 1)
-	}
-
-	if pc.t.DisableKeepAlives &&
-		!req.wantsClose() &&
-		!isProtocolSwitchHeader(req.Header) {
-		req.extraHeaders().Set("Connection", "close")
-	}
-
-	gone := make(chan struct{})
-	defer close(gone)
-
-	defer func() {
-		if err != nil {
-			pc.t.setReqCanceler(req.cancelKey, nil)
-		}
-	}()
-
-	const debugRoundTrip = false
-
-	// Write the request concurrently with waiting for a response,
-	// in case the server decides to reply before reading our full
-	// request body.
-	startBytesWritten := pc.nwrite
-	writeErrCh := make(chan error, 1)
-	pc.writech <- writeRequest{req, writeErrCh, continueCh}
-
-	resc := make(chan responseAndError)
-	pc.reqch <- requestAndChan{
-		req:        req.Request,
-		cancelKey:  req.cancelKey,
-		ch:         resc,
-		addedGzip:  requestedGzip,
-		continueCh: continueCh,
-		callerGone: gone,
-	}
-
-	var respHeaderTimer <-chan time.Time
-	cancelChan := req.Request.Cancel
-	ctxDoneChan := req.Context().Done()
-	pcClosed := pc.closech
-	canceled := false
-	for {
-		testHookWaitResLoop()
-		select {
-		case err := <-writeErrCh:
-			if debugRoundTrip {
-				req.logf("writeErrCh resv: %T/%#v", err, err)
-			}
-			if err != nil {
-				pc.close(fmt.Errorf("write error: %v", err))
-				return nil, pc.mapRoundTripError(req, startBytesWritten, err)
-			}
-			if d := pc.t.ResponseHeaderTimeout; d > 0 {
-				if debugRoundTrip {
-					req.logf("starting timer for %v", d)
-				}
-				timer := time.NewTimer(d)
-				defer timer.Stop() // prevent leaks
-				respHeaderTimer = timer.C
-			}
-		case <-pcClosed:
-			pcClosed = nil
-			if canceled || pc.t.replaceReqCanceler(req.cancelKey, nil) {
-				if debugRoundTrip {
-					req.logf("closech recv: %T %#v", pc.closed, pc.closed)
-				}
-				return nil, pc.mapRoundTripError(req, startBytesWritten, pc.closed)
-			}
-		case <-respHeaderTimer:
-			if debugRoundTrip {
-				req.logf("timeout waiting for response headers.")
-			}
-			pc.close(errTimeout)
-			return nil, errTimeout
-		case re := <-resc:
-			if (re.res == nil) == (re.err == nil) {
-				panic(fmt.Sprintf("internal error: exactly one of res or err should be set; nil=%v", re.res == nil))
-			}
-			if debugRoundTrip {
-				req.logf("resc recv: %p, %T/%#v", re.res, re.err, re.err)
-			}
-			if re.err != nil {
-				return nil, pc.mapRoundTripError(req, startBytesWritten, re.err)
-			}
-			return re.res, nil
-		case <-cancelChan:
-			canceled = pc.t.cancelRequest(req.cancelKey, errRequestCanceled)
-			cancelChan = nil
-		case <-ctxDoneChan:
-			canceled = pc.t.cancelRequest(req.cancelKey, req.Context().Err())
-			cancelChan = nil
-			ctxDoneChan = nil
-		}
-	}
-}
-
-// tLogKey is a context WithValue key for test debugging contexts containing
-// a t.Logf func. See export_test.go's Request.WithT method.
-type tLogKey struct{}
-
-func (tr *transportRequest) logf(format string, args ...any) {
-	if logf, ok := tr.Request.Context().Value(tLogKey{}).(func(string, ...any)); ok {
-		logf(time.Now().Format(time.RFC3339Nano)+": "+format, args...)
-	}
-}
-
-// markReused marks this connection as having been successfully used for a
-// request and response.
-func (pc *persistConn) markReused() {
-	pc.mu.Lock()
-	pc.reused = true
-	pc.mu.Unlock()
-}
-
-// close closes the underlying TCP connection and closes
-// the pc.closech channel.
-//
-// The provided err is only for testing and debugging; in normal
-// circumstances it should never be seen by users.
-func (pc *persistConn) close(err error) {
-	pc.mu.Lock()
-	defer pc.mu.Unlock()
-	pc.closeLocked(err)
-}
-
-func (pc *persistConn) closeLocked(err error) {
-	if err == nil {
-		panic("nil error")
-	}
-	pc.broken = true
-	if pc.closed == nil {
-		pc.closed = err
-		pc.t.decConnsPerHost(pc.cacheKey)
-		// Close HTTP/1 (pc.alt == nil) connection.
-		// HTTP/2 closes its connection itself.
-		if pc.alt == nil {
-			if err != errCallerOwnsConn {
-				pc.conn.Close()
-			}
-			close(pc.closech)
-		}
-	}
-	pc.mutateHeaderFunc = nil
-}
-
-var portMap = map[string]string{
-	"http":   "80",
-	"https":  "443",
-	"socks5": "1080",
-}
-
-// canonicalAddr returns url.Host but always with a ":port" suffix
-func canonicalAddr(url *url.URL) string {
-	addr := url.Hostname()
-	if v, err := idnaASCII(addr); err == nil {
-		addr = v
-	}
-	port := url.Port()
-	if port == "" {
-		port = portMap[url.Scheme]
-	}
-	return net.JoinHostPort(addr, port)
-}
-
-// bodyEOFSignal is used by the HTTP/1 transport when reading response
-// bodies to make sure we see the end of a response body before
-// proceeding and reading on the connection again.
-//
-// It wraps a ReadCloser but runs fn (if non-nil) at most
-// once, right before its final (error-producing) Read or Close call
-// returns. fn should return the new error to return from Read or Close.
-//
-// If earlyCloseFn is non-nil and Close is called before io.EOF is
-// seen, earlyCloseFn is called instead of fn, and its return value is
-// the return value from Close.
-type bodyEOFSignal struct {
-	body         io.ReadCloser
-	mu           sync.Mutex        // guards following 4 fields
-	closed       bool              // whether Close has been called
-	rerr         error             // sticky Read error
-	fn           func(error) error // err will be nil on Read io.EOF
-	earlyCloseFn func() error      // optional alt Close func used if io.EOF not seen
-}
-
-var errReadOnClosedResBody = errors.New("http: read on closed response body")
-
-func (es *bodyEOFSignal) Read(p []byte) (n int, err error) {
-	es.mu.Lock()
-	closed, rerr := es.closed, es.rerr
-	es.mu.Unlock()
-	if closed {
-		return 0, errReadOnClosedResBody
-	}
-	if rerr != nil {
-		return 0, rerr
-	}
-
-	n, err = es.body.Read(p)
-	if err != nil {
-		es.mu.Lock()
-		defer es.mu.Unlock()
-		if es.rerr == nil {
-			es.rerr = err
-		}
-		err = es.condfn(err)
-	}
-	return
-}
-
-func (es *bodyEOFSignal) Close() error {
-	es.mu.Lock()
-	defer es.mu.Unlock()
-	if es.closed {
-		return nil
-	}
-	es.closed = true
-	if es.earlyCloseFn != nil && es.rerr != io.EOF {
-		return es.earlyCloseFn()
-	}
-	err := es.body.Close()
-	return es.condfn(err)
-}
-
-// caller must hold es.mu.
-func (es *bodyEOFSignal) condfn(err error) error {
-	if es.fn == nil {
-		return err
-	}
-	err = es.fn(err)
-	es.fn = nil
-	return err
-}
-
-// gzipReader wraps a response body so it can lazily
-// call gzip.NewReader on the first call to Read
-type gzipReader struct {
-	_    incomparable
-	body *bodyEOFSignal // underlying HTTP/1 response body framing
-	zr   *gzip.Reader   // lazily-initialized gzip reader
-	zerr error          // any error from gzip.NewReader; sticky
-}
-
-func (gz *gzipReader) Read(p []byte) (n int, err error) {
-	if gz.zr == nil {
-		if gz.zerr == nil {
-			gz.zr, gz.zerr = gzip.NewReader(gz.body)
-		}
-		if gz.zerr != nil {
-			return 0, gz.zerr
-		}
-	}
-
-	gz.body.mu.Lock()
-	if gz.body.closed {
-		err = errReadOnClosedResBody
-	}
-	gz.body.mu.Unlock()
-
-	if err != nil {
-		return 0, err
-	}
-	return gz.zr.Read(p)
-}
-
-func (gz *gzipReader) Close() error {
-	return gz.body.Close()
-}
-
-type tlsHandshakeTimeoutError struct{}
-
-func (tlsHandshakeTimeoutError) Timeout() bool   { return true }
-func (tlsHandshakeTimeoutError) Temporary() bool { return true }
-func (tlsHandshakeTimeoutError) Error() string   { return "net/http: TLS handshake timeout" }
-
-// fakeLocker is a sync.Locker which does nothing. It's used to guard
-// test-only fields when not under test, to avoid runtime atomic
-// overhead.
-type fakeLocker struct{}
-
-func (fakeLocker) Lock()   {}
-func (fakeLocker) Unlock() {}
-
-// cloneTLSConfig returns a shallow clone of cfg, or a new zero tls.Config if
-// cfg is nil. This is safe to call even if cfg is in active use by a TLS
-// client or server.
-func cloneTLSConfig(cfg *tls.Config) *tls.Config {
-	if cfg == nil {
-		return &tls.Config{}
-	}
-	return cfg.Clone()
-}
-
-type connLRU struct {
-	ll *list.List // list.Element.Value type is of *persistConn
-	m  map[*persistConn]*list.Element
-}
-
-// add adds pc to the head of the linked list.
-func (cl *connLRU) add(pc *persistConn) {
-	if cl.ll == nil {
-		cl.ll = list.New()
-		cl.m = make(map[*persistConn]*list.Element)
-	}
-	ele := cl.ll.PushFront(pc)
-	if _, ok := cl.m[pc]; ok {
-		panic("persistConn was already in LRU")
-	}
-	cl.m[pc] = ele
-}
-
-func (cl *connLRU) removeOldest() *persistConn {
-	ele := cl.ll.Back()
-	pc := ele.Value.(*persistConn)
-	cl.ll.Remove(ele)
-	delete(cl.m, pc)
-	return pc
-}
-
-// remove removes pc from cl.
-func (cl *connLRU) remove(pc *persistConn) {
-	if ele, ok := cl.m[pc]; ok {
-		cl.ll.Remove(ele)
-		delete(cl.m, pc)
-	}
-}
-
-// len returns the number of items in the cache.
-func (cl *connLRU) len() int {
-	return len(cl.m)
-}
diff --git a/contrib/go/_std_1.18/src/net/iprawsock_posix.go b/contrib/go/_std_1.18/src/net/iprawsock_posix.go
deleted file mode 100644
index 74f977e1ef..0000000000
--- a/contrib/go/_std_1.18/src/net/iprawsock_posix.go
+++ /dev/null
@@ -1,147 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris || windows
-
-package net
-
-import (
-	"context"
-	"syscall"
-)
-
-func sockaddrToIP(sa syscall.Sockaddr) Addr {
-	switch sa := sa.(type) {
-	case *syscall.SockaddrInet4:
-		return &IPAddr{IP: sa.Addr[0:]}
-	case *syscall.SockaddrInet6:
-		return &IPAddr{IP: sa.Addr[0:], Zone: zoneCache.name(int(sa.ZoneId))}
-	}
-	return nil
-}
-
-func (a *IPAddr) family() int {
-	if a == nil || len(a.IP) <= IPv4len {
-		return syscall.AF_INET
-	}
-	if a.IP.To4() != nil {
-		return syscall.AF_INET
-	}
-	return syscall.AF_INET6
-}
-
-func (a *IPAddr) sockaddr(family int) (syscall.Sockaddr, error) {
-	if a == nil {
-		return nil, nil
-	}
-	return ipToSockaddr(family, a.IP, 0, a.Zone)
-}
-
-func (a *IPAddr) toLocal(net string) sockaddr {
-	return &IPAddr{loopbackIP(net), a.Zone}
-}
-
-func (c *IPConn) readFrom(b []byte) (int, *IPAddr, error) {
-	// TODO(cw,rsc): consider using readv if we know the family
-	// type to avoid the header trim/copy
-	var addr *IPAddr
-	n, sa, err := c.fd.readFrom(b)
-	switch sa := sa.(type) {
-	case *syscall.SockaddrInet4:
-		addr = &IPAddr{IP: sa.Addr[0:]}
-		n = stripIPv4Header(n, b)
-	case *syscall.SockaddrInet6:
-		addr = &IPAddr{IP: sa.Addr[0:], Zone: zoneCache.name(int(sa.ZoneId))}
-	}
-	return n, addr, err
-}
-
-func stripIPv4Header(n int, b []byte) int {
-	if len(b) < 20 {
-		return n
-	}
-	l := int(b[0]&0x0f) << 2
-	if 20 > l || l > len(b) {
-		return n
-	}
-	if b[0]>>4 != 4 {
-		return n
-	}
-	copy(b, b[l:])
-	return n - l
-}
-
-func (c *IPConn) readMsg(b, oob []byte) (n, oobn, flags int, addr *IPAddr, err error) {
-	var sa syscall.Sockaddr
-	n, oobn, flags, sa, err = c.fd.readMsg(b, oob, 0)
-	switch sa := sa.(type) {
-	case *syscall.SockaddrInet4:
-		addr = &IPAddr{IP: sa.Addr[0:]}
-	case *syscall.SockaddrInet6:
-		addr = &IPAddr{IP: sa.Addr[0:], Zone: zoneCache.name(int(sa.ZoneId))}
-	}
-	return
-}
-
-func (c *IPConn) writeTo(b []byte, addr *IPAddr) (int, error) {
-	if c.fd.isConnected {
-		return 0, ErrWriteToConnected
-	}
-	if addr == nil {
-		return 0, errMissingAddress
-	}
-	sa, err := addr.sockaddr(c.fd.family)
-	if err != nil {
-		return 0, err
-	}
-	return c.fd.writeTo(b, sa)
-}
-
-func (c *IPConn) writeMsg(b, oob []byte, addr *IPAddr) (n, oobn int, err error) {
-	if c.fd.isConnected {
-		return 0, 0, ErrWriteToConnected
-	}
-	if addr == nil {
-		return 0, 0, errMissingAddress
-	}
-	sa, err := addr.sockaddr(c.fd.family)
-	if err != nil {
-		return 0, 0, err
-	}
-	return c.fd.writeMsg(b, oob, sa)
-}
-
-func (sd *sysDialer) dialIP(ctx context.Context, laddr, raddr *IPAddr) (*IPConn, error) {
-	network, proto, err := parseNetwork(ctx, sd.network, true)
-	if err != nil {
-		return nil, err
-	}
-	switch network {
-	case "ip", "ip4", "ip6":
-	default:
-		return nil, UnknownNetworkError(sd.network)
-	}
-	fd, err := internetSocket(ctx, network, laddr, raddr, syscall.SOCK_RAW, proto, "dial", sd.Dialer.Control)
-	if err != nil {
-		return nil, err
-	}
-	return newIPConn(fd), nil
-}
-
-func (sl *sysListener) listenIP(ctx context.Context, laddr *IPAddr) (*IPConn, error) {
-	network, proto, err := parseNetwork(ctx, sl.network, true)
-	if err != nil {
-		return nil, err
-	}
-	switch network {
-	case "ip", "ip4", "ip6":
-	default:
-		return nil, UnknownNetworkError(sl.network)
-	}
-	fd, err := internetSocket(ctx, network, laddr, nil, syscall.SOCK_RAW, proto, "listen", sl.ListenConfig.Control)
-	if err != nil {
-		return nil, err
-	}
-	return newIPConn(fd), nil
-}
diff --git a/contrib/go/_std_1.18/src/net/ipsock_posix.go b/contrib/go/_std_1.18/src/net/ipsock_posix.go
deleted file mode 100644
index e433e8a91c..0000000000
--- a/contrib/go/_std_1.18/src/net/ipsock_posix.go
+++ /dev/null
@@ -1,228 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris || windows
-
-package net
-
-import (
-	"context"
-	"internal/poll"
-	"net/netip"
-	"runtime"
-	"syscall"
-)
-
-// probe probes IPv4, IPv6 and IPv4-mapped IPv6 communication
-// capabilities which are controlled by the IPV6_V6ONLY socket option
-// and kernel configuration.
-//
-// Should we try to use the IPv4 socket interface if we're only
-// dealing with IPv4 sockets? As long as the host system understands
-// IPv4-mapped IPv6, it's okay to pass IPv4-mapped IPv6 addresses to
-// the IPv6 interface. That simplifies our code and is most
-// general. Unfortunately, we need to run on kernels built without
-// IPv6 support too. So probe the kernel to figure it out.
-func (p *ipStackCapabilities) probe() {
-	s, err := sysSocket(syscall.AF_INET, syscall.SOCK_STREAM, syscall.IPPROTO_TCP)
-	switch err {
-	case syscall.EAFNOSUPPORT, syscall.EPROTONOSUPPORT:
-	case nil:
-		poll.CloseFunc(s)
-		p.ipv4Enabled = true
-	}
-	var probes = []struct {
-		laddr TCPAddr
-		value int
-	}{
-		// IPv6 communication capability
-		{laddr: TCPAddr{IP: ParseIP("::1")}, value: 1},
-		// IPv4-mapped IPv6 address communication capability
-		{laddr: TCPAddr{IP: IPv4(127, 0, 0, 1)}, value: 0},
-	}
-	switch runtime.GOOS {
-	case "dragonfly", "openbsd":
-		// The latest DragonFly BSD and OpenBSD kernels don't
-		// support IPV6_V6ONLY=0. They always return an error
-		// and we don't need to probe the capability.
-		probes = probes[:1]
-	}
-	for i := range probes {
-		s, err := sysSocket(syscall.AF_INET6, syscall.SOCK_STREAM, syscall.IPPROTO_TCP)
-		if err != nil {
-			continue
-		}
-		defer poll.CloseFunc(s)
-		syscall.SetsockoptInt(s, syscall.IPPROTO_IPV6, syscall.IPV6_V6ONLY, probes[i].value)
-		sa, err := probes[i].laddr.sockaddr(syscall.AF_INET6)
-		if err != nil {
-			continue
-		}
-		if err := syscall.Bind(s, sa); err != nil {
-			continue
-		}
-		if i == 0 {
-			p.ipv6Enabled = true
-		} else {
-			p.ipv4MappedIPv6Enabled = true
-		}
-	}
-}
-
-// favoriteAddrFamily returns the appropriate address family for the
-// given network, laddr, raddr and mode.
-//
-// If mode indicates "listen" and laddr is a wildcard, we assume that
-// the user wants to make a passive-open connection with a wildcard
-// address family, both AF_INET and AF_INET6, and a wildcard address
-// like the following:
-//
-//	- A listen for a wildcard communication domain, "tcp" or
-//	  "udp", with a wildcard address: If the platform supports
-//	  both IPv6 and IPv4-mapped IPv6 communication capabilities,
-//	  or does not support IPv4, we use a dual stack, AF_INET6 and
-//	  IPV6_V6ONLY=0, wildcard address listen. The dual stack
-//	  wildcard address listen may fall back to an IPv6-only,
-//	  AF_INET6 and IPV6_V6ONLY=1, wildcard address listen.
-//	  Otherwise we prefer an IPv4-only, AF_INET, wildcard address
-//	  listen.
-//
-//	- A listen for a wildcard communication domain, "tcp" or
-//	  "udp", with an IPv4 wildcard address: same as above.
-//
-//	- A listen for a wildcard communication domain, "tcp" or
-//	  "udp", with an IPv6 wildcard address: same as above.
-//
-//	- A listen for an IPv4 communication domain, "tcp4" or "udp4",
-//	  with an IPv4 wildcard address: We use an IPv4-only, AF_INET,
-//	  wildcard address listen.
-//
-//	- A listen for an IPv6 communication domain, "tcp6" or "udp6",
-//	  with an IPv6 wildcard address: We use an IPv6-only, AF_INET6
-//	  and IPV6_V6ONLY=1, wildcard address listen.
-//
-// Otherwise guess: If the addresses are IPv4 then returns AF_INET,
-// or else returns AF_INET6. It also returns a boolean value what
-// designates IPV6_V6ONLY option.
-//
-// Note that the latest DragonFly BSD and OpenBSD kernels allow
-// neither "net.inet6.ip6.v6only=1" change nor IPPROTO_IPV6 level
-// IPV6_V6ONLY socket option setting.
-func favoriteAddrFamily(network string, laddr, raddr sockaddr, mode string) (family int, ipv6only bool) {
-	switch network[len(network)-1] {
-	case '4':
-		return syscall.AF_INET, false
-	case '6':
-		return syscall.AF_INET6, true
-	}
-
-	if mode == "listen" && (laddr == nil || laddr.isWildcard()) {
-		if supportsIPv4map() || !supportsIPv4() {
-			return syscall.AF_INET6, false
-		}
-		if laddr == nil {
-			return syscall.AF_INET, false
-		}
-		return laddr.family(), false
-	}
-
-	if (laddr == nil || laddr.family() == syscall.AF_INET) &&
-		(raddr == nil || raddr.family() == syscall.AF_INET) {
-		return syscall.AF_INET, false
-	}
-	return syscall.AF_INET6, false
-}
-
-func internetSocket(ctx context.Context, net string, laddr, raddr sockaddr, sotype, proto int, mode string, ctrlFn func(string, string, syscall.RawConn) error) (fd *netFD, err error) {
-	if (runtime.GOOS == "aix" || runtime.GOOS == "windows" || runtime.GOOS == "openbsd") && mode == "dial" && raddr.isWildcard() {
-		raddr = raddr.toLocal(net)
-	}
-	family, ipv6only := favoriteAddrFamily(net, laddr, raddr, mode)
-	return socket(ctx, net, family, sotype, proto, ipv6only, laddr, raddr, ctrlFn)
-}
-
-func ipToSockaddrInet4(ip IP, port int) (syscall.SockaddrInet4, error) {
-	if len(ip) == 0 {
-		ip = IPv4zero
-	}
-	ip4 := ip.To4()
-	if ip4 == nil {
-		return syscall.SockaddrInet4{}, &AddrError{Err: "non-IPv4 address", Addr: ip.String()}
-	}
-	sa := syscall.SockaddrInet4{Port: port}
-	copy(sa.Addr[:], ip4)
-	return sa, nil
-}
-
-func ipToSockaddrInet6(ip IP, port int, zone string) (syscall.SockaddrInet6, error) {
-	// In general, an IP wildcard address, which is either
-	// "0.0.0.0" or "::", means the entire IP addressing
-	// space. For some historical reason, it is used to
-	// specify "any available address" on some operations
-	// of IP node.
-	//
-	// When the IP node supports IPv4-mapped IPv6 address,
-	// we allow a listener to listen to the wildcard
-	// address of both IP addressing spaces by specifying
-	// IPv6 wildcard address.
-	if len(ip) == 0 || ip.Equal(IPv4zero) {
-		ip = IPv6zero
-	}
-	// We accept any IPv6 address including IPv4-mapped
-	// IPv6 address.
-	ip6 := ip.To16()
-	if ip6 == nil {
-		return syscall.SockaddrInet6{}, &AddrError{Err: "non-IPv6 address", Addr: ip.String()}
-	}
-	sa := syscall.SockaddrInet6{Port: port, ZoneId: uint32(zoneCache.index(zone))}
-	copy(sa.Addr[:], ip6)
-	return sa, nil
-}
-
-func ipToSockaddr(family int, ip IP, port int, zone string) (syscall.Sockaddr, error) {
-	switch family {
-	case syscall.AF_INET:
-		sa, err := ipToSockaddrInet4(ip, port)
-		if err != nil {
-			return nil, err
-		}
-		return &sa, nil
-	case syscall.AF_INET6:
-		sa, err := ipToSockaddrInet6(ip, port, zone)
-		if err != nil {
-			return nil, err
-		}
-		return &sa, nil
-	}
-	return nil, &AddrError{Err: "invalid address family", Addr: ip.String()}
-}
-
-func addrPortToSockaddrInet4(ap netip.AddrPort) (syscall.SockaddrInet4, error) {
-	// ipToSockaddrInet4 has special handling here for zero length slices.
-	// We do not, because netip has no concept of a generic zero IP address.
-	addr := ap.Addr()
-	if !addr.Is4() {
-		return syscall.SockaddrInet4{}, &AddrError{Err: "non-IPv4 address", Addr: addr.String()}
-	}
-	sa := syscall.SockaddrInet4{
-		Addr: addr.As4(),
-		Port: int(ap.Port()),
-	}
-	return sa, nil
-}
-
-func addrPortToSockaddrInet6(ap netip.AddrPort) (syscall.SockaddrInet6, error) {
-	// ipToSockaddrInet6 has special handling here for zero length slices.
-	// We do not, because netip has no concept of a generic zero IP address.
-	addr := ap.Addr()
-	if !addr.Is6() {
-		return syscall.SockaddrInet6{}, &AddrError{Err: "non-IPv6 address", Addr: addr.String()}
-	}
-	sa := syscall.SockaddrInet6{
-		Addr:   addr.As16(),
-		Port:   int(ap.Port()),
-		ZoneId: uint32(zoneCache.index(addr.Zone())),
-	}
-	return sa, nil
-}
diff --git a/contrib/go/_std_1.18/src/net/lookup.go b/contrib/go/_std_1.18/src/net/lookup.go
deleted file mode 100644
index c7b8dc6905..0000000000
--- a/contrib/go/_std_1.18/src/net/lookup.go
+++ /dev/null
@@ -1,667 +0,0 @@
-// Copyright 2012 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package net
-
-import (
-	"context"
-	"internal/nettrace"
-	"internal/singleflight"
-	"net/netip"
-	"sync"
-)
-
-// protocols contains minimal mappings between internet protocol
-// names and numbers for platforms that don't have a complete list of
-// protocol numbers.
-//
-// See https://www.iana.org/assignments/protocol-numbers
-//
-// On Unix, this map is augmented by readProtocols via lookupProtocol.
-var protocols = map[string]int{
-	"icmp":      1,
-	"igmp":      2,
-	"tcp":       6,
-	"udp":       17,
-	"ipv6-icmp": 58,
-}
-
-// services contains minimal mappings between services names and port
-// numbers for platforms that don't have a complete list of port numbers.
-//
-// See https://www.iana.org/assignments/service-names-port-numbers
-//
-// On Unix, this map is augmented by readServices via goLookupPort.
-var services = map[string]map[string]int{
-	"udp": {
-		"domain": 53,
-	},
-	"tcp": {
-		"ftp":    21,
-		"ftps":   990,
-		"gopher": 70, // ʕ◔ϖ◔ʔ
-		"http":   80,
-		"https":  443,
-		"imap2":  143,
-		"imap3":  220,
-		"imaps":  993,
-		"pop3":   110,
-		"pop3s":  995,
-		"smtp":   25,
-		"ssh":    22,
-		"telnet": 23,
-	},
-}
-
-// dnsWaitGroup can be used by tests to wait for all DNS goroutines to
-// complete. This avoids races on the test hooks.
-var dnsWaitGroup sync.WaitGroup
-
-const maxProtoLength = len("RSVP-E2E-IGNORE") + 10 // with room to grow
-
-func lookupProtocolMap(name string) (int, error) {
-	var lowerProtocol [maxProtoLength]byte
-	n := copy(lowerProtocol[:], name)
-	lowerASCIIBytes(lowerProtocol[:n])
-	proto, found := protocols[string(lowerProtocol[:n])]
-	if !found || n != len(name) {
-		return 0, &AddrError{Err: "unknown IP protocol specified", Addr: name}
-	}
-	return proto, nil
-}
-
-// maxPortBufSize is the longest reasonable name of a service
-// (non-numeric port).
-// Currently the longest known IANA-unregistered name is
-// "mobility-header", so we use that length, plus some slop in case
-// something longer is added in the future.
-const maxPortBufSize = len("mobility-header") + 10
-
-func lookupPortMap(network, service string) (port int, error error) {
-	switch network {
-	case "tcp4", "tcp6":
-		network = "tcp"
-	case "udp4", "udp6":
-		network = "udp"
-	}
-
-	if m, ok := services[network]; ok {
-		var lowerService [maxPortBufSize]byte
-		n := copy(lowerService[:], service)
-		lowerASCIIBytes(lowerService[:n])
-		if port, ok := m[string(lowerService[:n])]; ok && n == len(service) {
-			return port, nil
-		}
-	}
-	return 0, &AddrError{Err: "unknown port", Addr: network + "/" + service}
-}
-
-// ipVersion returns the provided network's IP version: '4', '6' or 0
-// if network does not end in a '4' or '6' byte.
-func ipVersion(network string) byte {
-	if network == "" {
-		return 0
-	}
-	n := network[len(network)-1]
-	if n != '4' && n != '6' {
-		n = 0
-	}
-	return n
-}
-
-// DefaultResolver is the resolver used by the package-level Lookup
-// functions and by Dialers without a specified Resolver.
-var DefaultResolver = &Resolver{}
-
-// A Resolver looks up names and numbers.
-//
-// A nil *Resolver is equivalent to a zero Resolver.
-type Resolver struct {
-	// PreferGo controls whether Go's built-in DNS resolver is preferred
-	// on platforms where it's available. It is equivalent to setting
-	// GODEBUG=netdns=go, but scoped to just this resolver.
-	PreferGo bool
-
-	// StrictErrors controls the behavior of temporary errors
-	// (including timeout, socket errors, and SERVFAIL) when using
-	// Go's built-in resolver. For a query composed of multiple
-	// sub-queries (such as an A+AAAA address lookup, or walking the
-	// DNS search list), this option causes such errors to abort the
-	// whole query instead of returning a partial result. This is
-	// not enabled by default because it may affect compatibility
-	// with resolvers that process AAAA queries incorrectly.
-	StrictErrors bool
-
-	// Dial optionally specifies an alternate dialer for use by
-	// Go's built-in DNS resolver to make TCP and UDP connections
-	// to DNS services. The host in the address parameter will
-	// always be a literal IP address and not a host name, and the
-	// port in the address parameter will be a literal port number
-	// and not a service name.
-	// If the Conn returned is also a PacketConn, sent and received DNS
-	// messages must adhere to RFC 1035 section 4.2.1, "UDP usage".
-	// Otherwise, DNS messages transmitted over Conn must adhere
-	// to RFC 7766 section 5, "Transport Protocol Selection".
-	// If nil, the default dialer is used.
-	Dial func(ctx context.Context, network, address string) (Conn, error)
-
-	// lookupGroup merges LookupIPAddr calls together for lookups for the same
-	// host. The lookupGroup key is the LookupIPAddr.host argument.
-	// The return values are ([]IPAddr, error).
-	lookupGroup singleflight.Group
-
-	// TODO(bradfitz): optional interface impl override hook
-	// TODO(bradfitz): Timeout time.Duration?
-}
-
-func (r *Resolver) preferGo() bool     { return r != nil && r.PreferGo }
-func (r *Resolver) strictErrors() bool { return r != nil && r.StrictErrors }
-
-func (r *Resolver) getLookupGroup() *singleflight.Group {
-	if r == nil {
-		return &DefaultResolver.lookupGroup
-	}
-	return &r.lookupGroup
-}
-
-// LookupHost looks up the given host using the local resolver.
-// It returns a slice of that host's addresses.
-//
-// LookupHost uses context.Background internally; to specify the context, use
-// Resolver.LookupHost.
-func LookupHost(host string) (addrs []string, err error) {
-	return DefaultResolver.LookupHost(context.Background(), host)
-}
-
-// LookupHost looks up the given host using the local resolver.
-// It returns a slice of that host's addresses.
-func (r *Resolver) LookupHost(ctx context.Context, host string) (addrs []string, err error) {
-	// Make sure that no matter what we do later, host=="" is rejected.
-	// parseIP, for example, does accept empty strings.
-	if host == "" {
-		return nil, &DNSError{Err: errNoSuchHost.Error(), Name: host, IsNotFound: true}
-	}
-	if ip, _ := parseIPZone(host); ip != nil {
-		return []string{host}, nil
-	}
-	return r.lookupHost(ctx, host)
-}
-
-// LookupIP looks up host using the local resolver.
-// It returns a slice of that host's IPv4 and IPv6 addresses.
-func LookupIP(host string) ([]IP, error) {
-	addrs, err := DefaultResolver.LookupIPAddr(context.Background(), host)
-	if err != nil {
-		return nil, err
-	}
-	ips := make([]IP, len(addrs))
-	for i, ia := range addrs {
-		ips[i] = ia.IP
-	}
-	return ips, nil
-}
-
-// LookupIPAddr looks up host using the local resolver.
-// It returns a slice of that host's IPv4 and IPv6 addresses.
-func (r *Resolver) LookupIPAddr(ctx context.Context, host string) ([]IPAddr, error) {
-	return r.lookupIPAddr(ctx, "ip", host)
-}
-
-// LookupIP looks up host for the given network using the local resolver.
-// It returns a slice of that host's IP addresses of the type specified by
-// network.
-// network must be one of "ip", "ip4" or "ip6".
-func (r *Resolver) LookupIP(ctx context.Context, network, host string) ([]IP, error) {
-	afnet, _, err := parseNetwork(ctx, network, false)
-	if err != nil {
-		return nil, err
-	}
-	switch afnet {
-	case "ip", "ip4", "ip6":
-	default:
-		return nil, UnknownNetworkError(network)
-	}
-	addrs, err := r.internetAddrList(ctx, afnet, host)
-	if err != nil {
-		return nil, err
-	}
-	ips := make([]IP, 0, len(addrs))
-	for _, addr := range addrs {
-		ips = append(ips, addr.(*IPAddr).IP)
-	}
-	return ips, nil
-}
-
-// LookupNetIP looks up host using the local resolver.
-// It returns a slice of that host's IP addresses of the type specified by
-// network.
-// The network must be one of "ip", "ip4" or "ip6".
-func (r *Resolver) LookupNetIP(ctx context.Context, network, host string) ([]netip.Addr, error) {
-	// TODO(bradfitz): make this efficient, making the internal net package
-	// type throughout be netip.Addr and only converting to the net.IP slice
-	// version at the edge. But for now (2021-10-20), this is a wrapper around
-	// the old way.
-	ips, err := r.LookupIP(ctx, network, host)
-	if err != nil {
-		return nil, err
-	}
-	ret := make([]netip.Addr, 0, len(ips))
-	for _, ip := range ips {
-		if a, ok := netip.AddrFromSlice(ip); ok {
-			ret = append(ret, a)
-		}
-	}
-	return ret, nil
-}
-
-// onlyValuesCtx is a context that uses an underlying context
-// for value lookup if the underlying context hasn't yet expired.
-type onlyValuesCtx struct {
-	context.Context
-	lookupValues context.Context
-}
-
-var _ context.Context = (*onlyValuesCtx)(nil)
-
-// Value performs a lookup if the original context hasn't expired.
-func (ovc *onlyValuesCtx) Value(key any) any {
-	select {
-	case <-ovc.lookupValues.Done():
-		return nil
-	default:
-		return ovc.lookupValues.Value(key)
-	}
-}
-
-// withUnexpiredValuesPreserved returns a context.Context that only uses lookupCtx
-// for its values, otherwise it is never canceled and has no deadline.
-// If the lookup context expires, any looked up values will return nil.
-// See Issue 28600.
-func withUnexpiredValuesPreserved(lookupCtx context.Context) context.Context {
-	return &onlyValuesCtx{Context: context.Background(), lookupValues: lookupCtx}
-}
-
-// lookupIPAddr looks up host using the local resolver and particular network.
-// It returns a slice of that host's IPv4 and IPv6 addresses.
-func (r *Resolver) lookupIPAddr(ctx context.Context, network, host string) ([]IPAddr, error) {
-	// Make sure that no matter what we do later, host=="" is rejected.
-	// parseIP, for example, does accept empty strings.
-	if host == "" {
-		return nil, &DNSError{Err: errNoSuchHost.Error(), Name: host, IsNotFound: true}
-	}
-	if ip, zone := parseIPZone(host); ip != nil {
-		return []IPAddr{{IP: ip, Zone: zone}}, nil
-	}
-	trace, _ := ctx.Value(nettrace.TraceKey{}).(*nettrace.Trace)
-	if trace != nil && trace.DNSStart != nil {
-		trace.DNSStart(host)
-	}
-	// The underlying resolver func is lookupIP by default but it
-	// can be overridden by tests. This is needed by net/http, so it
-	// uses a context key instead of unexported variables.
-	resolverFunc := r.lookupIP
-	if alt, _ := ctx.Value(nettrace.LookupIPAltResolverKey{}).(func(context.Context, string, string) ([]IPAddr, error)); alt != nil {
-		resolverFunc = alt
-	}
-
-	// We don't want a cancellation of ctx to affect the
-	// lookupGroup operation. Otherwise if our context gets
-	// canceled it might cause an error to be returned to a lookup
-	// using a completely different context. However we need to preserve
-	// only the values in context. See Issue 28600.
-	lookupGroupCtx, lookupGroupCancel := context.WithCancel(withUnexpiredValuesPreserved(ctx))
-
-	lookupKey := network + "\000" + host
-	dnsWaitGroup.Add(1)
-	ch, called := r.getLookupGroup().DoChan(lookupKey, func() (any, error) {
-		defer dnsWaitGroup.Done()
-		return testHookLookupIP(lookupGroupCtx, resolverFunc, network, host)
-	})
-	if !called {
-		dnsWaitGroup.Done()
-	}
-
-	select {
-	case <-ctx.Done():
-		// Our context was canceled. If we are the only
-		// goroutine looking up this key, then drop the key
-		// from the lookupGroup and cancel the lookup.
-		// If there are other goroutines looking up this key,
-		// let the lookup continue uncanceled, and let later
-		// lookups with the same key share the result.
-		// See issues 8602, 20703, 22724.
-		if r.getLookupGroup().ForgetUnshared(lookupKey) {
-			lookupGroupCancel()
-		} else {
-			go func() {
-				<-ch
-				lookupGroupCancel()
-			}()
-		}
-		ctxErr := ctx.Err()
-		err := &DNSError{
-			Err:       mapErr(ctxErr).Error(),
-			Name:      host,
-			IsTimeout: ctxErr == context.DeadlineExceeded,
-		}
-		if trace != nil && trace.DNSDone != nil {
-			trace.DNSDone(nil, false, err)
-		}
-		return nil, err
-	case r := <-ch:
-		lookupGroupCancel()
-		err := r.Err
-		if err != nil {
-			if _, ok := err.(*DNSError); !ok {
-				isTimeout := false
-				if err == context.DeadlineExceeded {
-					isTimeout = true
-				} else if terr, ok := err.(timeout); ok {
-					isTimeout = terr.Timeout()
-				}
-				err = &DNSError{
-					Err:       err.Error(),
-					Name:      host,
-					IsTimeout: isTimeout,
-				}
-			}
-		}
-		if trace != nil && trace.DNSDone != nil {
-			addrs, _ := r.Val.([]IPAddr)
-			trace.DNSDone(ipAddrsEface(addrs), r.Shared, err)
-		}
-		return lookupIPReturn(r.Val, err, r.Shared)
-	}
-}
-
-// lookupIPReturn turns the return values from singleflight.Do into
-// the return values from LookupIP.
-func lookupIPReturn(addrsi any, err error, shared bool) ([]IPAddr, error) {
-	if err != nil {
-		return nil, err
-	}
-	addrs := addrsi.([]IPAddr)
-	if shared {
-		clone := make([]IPAddr, len(addrs))
-		copy(clone, addrs)
-		addrs = clone
-	}
-	return addrs, nil
-}
-
-// ipAddrsEface returns an empty interface slice of addrs.
-func ipAddrsEface(addrs []IPAddr) []any {
-	s := make([]any, len(addrs))
-	for i, v := range addrs {
-		s[i] = v
-	}
-	return s
-}
-
-// LookupPort looks up the port for the given network and service.
-//
-// LookupPort uses context.Background internally; to specify the context, use
-// Resolver.LookupPort.
-func LookupPort(network, service string) (port int, err error) {
-	return DefaultResolver.LookupPort(context.Background(), network, service)
-}
-
-// LookupPort looks up the port for the given network and service.
-func (r *Resolver) LookupPort(ctx context.Context, network, service string) (port int, err error) {
-	port, needsLookup := parsePort(service)
-	if needsLookup {
-		switch network {
-		case "tcp", "tcp4", "tcp6", "udp", "udp4", "udp6":
-		case "": // a hint wildcard for Go 1.0 undocumented behavior
-			network = "ip"
-		default:
-			return 0, &AddrError{Err: "unknown network", Addr: network}
-		}
-		port, err = r.lookupPort(ctx, network, service)
-		if err != nil {
-			return 0, err
-		}
-	}
-	if 0 > port || port > 65535 {
-		return 0, &AddrError{Err: "invalid port", Addr: service}
-	}
-	return port, nil
-}
-
-// LookupCNAME returns the canonical name for the given host.
-// Callers that do not care about the canonical name can call
-// LookupHost or LookupIP directly; both take care of resolving
-// the canonical name as part of the lookup.
-//
-// A canonical name is the final name after following zero
-// or more CNAME records.
-// LookupCNAME does not return an error if host does not
-// contain DNS "CNAME" records, as long as host resolves to
-// address records.
-//
-// The returned canonical name is validated to be a properly
-// formatted presentation-format domain name.
-//
-// LookupCNAME uses context.Background internally; to specify the context, use
-// Resolver.LookupCNAME.
-func LookupCNAME(host string) (cname string, err error) {
-	return DefaultResolver.LookupCNAME(context.Background(), host)
-}
-
-// LookupCNAME returns the canonical name for the given host.
-// Callers that do not care about the canonical name can call
-// LookupHost or LookupIP directly; both take care of resolving
-// the canonical name as part of the lookup.
-//
-// A canonical name is the final name after following zero
-// or more CNAME records.
-// LookupCNAME does not return an error if host does not
-// contain DNS "CNAME" records, as long as host resolves to
-// address records.
-//
-// The returned canonical name is validated to be a properly
-// formatted presentation-format domain name.
-func (r *Resolver) LookupCNAME(ctx context.Context, host string) (string, error) {
-	cname, err := r.lookupCNAME(ctx, host)
-	if err != nil {
-		return "", err
-	}
-	if !isDomainName(cname) {
-		return "", &DNSError{Err: errMalformedDNSRecordsDetail, Name: host}
-	}
-	return cname, nil
-}
-
-// LookupSRV tries to resolve an SRV query of the given service,
-// protocol, and domain name. The proto is "tcp" or "udp".
-// The returned records are sorted by priority and randomized
-// by weight within a priority.
-//
-// LookupSRV constructs the DNS name to look up following RFC 2782.
-// That is, it looks up _service._proto.name. To accommodate services
-// publishing SRV records under non-standard names, if both service
-// and proto are empty strings, LookupSRV looks up name directly.
-//
-// The returned service names are validated to be properly
-// formatted presentation-format domain names. If the response contains
-// invalid names, those records are filtered out and an error
-// will be returned alongside the remaining results, if any.
-func LookupSRV(service, proto, name string) (cname string, addrs []*SRV, err error) {
-	return DefaultResolver.LookupSRV(context.Background(), service, proto, name)
-}
-
-// LookupSRV tries to resolve an SRV query of the given service,
-// protocol, and domain name. The proto is "tcp" or "udp".
-// The returned records are sorted by priority and randomized
-// by weight within a priority.
-//
-// LookupSRV constructs the DNS name to look up following RFC 2782.
-// That is, it looks up _service._proto.name. To accommodate services
-// publishing SRV records under non-standard names, if both service
-// and proto are empty strings, LookupSRV looks up name directly.
-//
-// The returned service names are validated to be properly
-// formatted presentation-format domain names. If the response contains
-// invalid names, those records are filtered out and an error
-// will be returned alongside the remaining results, if any.
-func (r *Resolver) LookupSRV(ctx context.Context, service, proto, name string) (string, []*SRV, error) {
-	cname, addrs, err := r.lookupSRV(ctx, service, proto, name)
-	if err != nil {
-		return "", nil, err
-	}
-	if cname != "" && !isDomainName(cname) {
-		return "", nil, &DNSError{Err: "SRV header name is invalid", Name: name}
-	}
-	filteredAddrs := make([]*SRV, 0, len(addrs))
-	for _, addr := range addrs {
-		if addr == nil {
-			continue
-		}
-		if !isDomainName(addr.Target) {
-			continue
-		}
-		filteredAddrs = append(filteredAddrs, addr)
-	}
-	if len(addrs) != len(filteredAddrs) {
-		return cname, filteredAddrs, &DNSError{Err: errMalformedDNSRecordsDetail, Name: name}
-	}
-	return cname, filteredAddrs, nil
-}
-
-// LookupMX returns the DNS MX records for the given domain name sorted by preference.
-//
-// The returned mail server names are validated to be properly
-// formatted presentation-format domain names. If the response contains
-// invalid names, those records are filtered out and an error
-// will be returned alongside the remaining results, if any.
-//
-// LookupMX uses context.Background internally; to specify the context, use
-// Resolver.LookupMX.
-func LookupMX(name string) ([]*MX, error) {
-	return DefaultResolver.LookupMX(context.Background(), name)
-}
-
-// LookupMX returns the DNS MX records for the given domain name sorted by preference.
-//
-// The returned mail server names are validated to be properly
-// formatted presentation-format domain names. If the response contains
-// invalid names, those records are filtered out and an error
-// will be returned alongside the remaining results, if any.
-func (r *Resolver) LookupMX(ctx context.Context, name string) ([]*MX, error) {
-	records, err := r.lookupMX(ctx, name)
-	if err != nil {
-		return nil, err
-	}
-	filteredMX := make([]*MX, 0, len(records))
-	for _, mx := range records {
-		if mx == nil {
-			continue
-		}
-		if !isDomainName(mx.Host) {
-			continue
-		}
-		filteredMX = append(filteredMX, mx)
-	}
-	if len(records) != len(filteredMX) {
-		return filteredMX, &DNSError{Err: errMalformedDNSRecordsDetail, Name: name}
-	}
-	return filteredMX, nil
-}
-
-// LookupNS returns the DNS NS records for the given domain name.
-//
-// The returned name server names are validated to be properly
-// formatted presentation-format domain names. If the response contains
-// invalid names, those records are filtered out and an error
-// will be returned alongside the remaining results, if any.
-//
-// LookupNS uses context.Background internally; to specify the context, use
-// Resolver.LookupNS.
-func LookupNS(name string) ([]*NS, error) {
-	return DefaultResolver.LookupNS(context.Background(), name)
-}
-
-// LookupNS returns the DNS NS records for the given domain name.
-//
-// The returned name server names are validated to be properly
-// formatted presentation-format domain names. If the response contains
-// invalid names, those records are filtered out and an error
-// will be returned alongside the remaining results, if any.
-func (r *Resolver) LookupNS(ctx context.Context, name string) ([]*NS, error) {
-	records, err := r.lookupNS(ctx, name)
-	if err != nil {
-		return nil, err
-	}
-	filteredNS := make([]*NS, 0, len(records))
-	for _, ns := range records {
-		if ns == nil {
-			continue
-		}
-		if !isDomainName(ns.Host) {
-			continue
-		}
-		filteredNS = append(filteredNS, ns)
-	}
-	if len(records) != len(filteredNS) {
-		return filteredNS, &DNSError{Err: errMalformedDNSRecordsDetail, Name: name}
-	}
-	return filteredNS, nil
-}
-
-// LookupTXT returns the DNS TXT records for the given domain name.
-//
-// LookupTXT uses context.Background internally; to specify the context, use
-// Resolver.LookupTXT.
-func LookupTXT(name string) ([]string, error) {
-	return DefaultResolver.lookupTXT(context.Background(), name)
-}
-
-// LookupTXT returns the DNS TXT records for the given domain name.
-func (r *Resolver) LookupTXT(ctx context.Context, name string) ([]string, error) {
-	return r.lookupTXT(ctx, name)
-}
-
-// LookupAddr performs a reverse lookup for the given address, returning a list
-// of names mapping to that address.
-//
-// The returned names are validated to be properly formatted presentation-format
-// domain names. If the response contains invalid names, those records are filtered
-// out and an error will be returned alongside the remaining results, if any.
-//
-// When using the host C library resolver, at most one result will be
-// returned. To bypass the host resolver, use a custom Resolver.
-//
-// LookupAddr uses context.Background internally; to specify the context, use
-// Resolver.LookupAddr.
-func LookupAddr(addr string) (names []string, err error) {
-	return DefaultResolver.LookupAddr(context.Background(), addr)
-}
-
-// LookupAddr performs a reverse lookup for the given address, returning a list
-// of names mapping to that address.
-//
-// The returned names are validated to be properly formatted presentation-format
-// domain names. If the response contains invalid names, those records are filtered
-// out and an error will be returned alongside the remaining results, if any.
-func (r *Resolver) LookupAddr(ctx context.Context, addr string) ([]string, error) {
-	names, err := r.lookupAddr(ctx, addr)
-	if err != nil {
-		return nil, err
-	}
-	filteredNames := make([]string, 0, len(names))
-	for _, name := range names {
-		if isDomainName(name) {
-			filteredNames = append(filteredNames, name)
-		}
-	}
-	if len(names) != len(filteredNames) {
-		return filteredNames, &DNSError{Err: errMalformedDNSRecordsDetail, Name: addr}
-	}
-	return filteredNames, nil
-}
-
-// errMalformedDNSRecordsDetail is the DNSError detail which is returned when a Resolver.Lookup...
-// method receives DNS records which contain invalid DNS names. This may be returned alongside
-// results which have had the malformed records filtered out.
-var errMalformedDNSRecordsDetail = "DNS response contained records which contain invalid names"
diff --git a/contrib/go/_std_1.18/src/net/lookup_unix.go b/contrib/go/_std_1.18/src/net/lookup_unix.go
deleted file mode 100644
index 255a19dfdb..0000000000
--- a/contrib/go/_std_1.18/src/net/lookup_unix.go
+++ /dev/null
@@ -1,353 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
-
-package net
-
-import (
-	"context"
-	"internal/bytealg"
-	"sync"
-	"syscall"
-
-	"golang.org/x/net/dns/dnsmessage"
-)
-
-var onceReadProtocols sync.Once
-
-// readProtocols loads contents of /etc/protocols into protocols map
-// for quick access.
-func readProtocols() {
-	file, err := open("/etc/protocols")
-	if err != nil {
-		return
-	}
-	defer file.close()
-
-	for line, ok := file.readLine(); ok; line, ok = file.readLine() {
-		// tcp    6   TCP    # transmission control protocol
-		if i := bytealg.IndexByteString(line, '#'); i >= 0 {
-			line = line[0:i]
-		}
-		f := getFields(line)
-		if len(f) < 2 {
-			continue
-		}
-		if proto, _, ok := dtoi(f[1]); ok {
-			if _, ok := protocols[f[0]]; !ok {
-				protocols[f[0]] = proto
-			}
-			for _, alias := range f[2:] {
-				if _, ok := protocols[alias]; !ok {
-					protocols[alias] = proto
-				}
-			}
-		}
-	}
-}
-
-// lookupProtocol looks up IP protocol name in /etc/protocols and
-// returns correspondent protocol number.
-func lookupProtocol(_ context.Context, name string) (int, error) {
-	onceReadProtocols.Do(readProtocols)
-	return lookupProtocolMap(name)
-}
-
-func (r *Resolver) dial(ctx context.Context, network, server string) (Conn, error) {
-	// Calling Dial here is scary -- we have to be sure not to
-	// dial a name that will require a DNS lookup, or Dial will
-	// call back here to translate it. The DNS config parser has
-	// already checked that all the cfg.servers are IP
-	// addresses, which Dial will use without a DNS lookup.
-	var c Conn
-	var err error
-	if r != nil && r.Dial != nil {
-		c, err = r.Dial(ctx, network, server)
-	} else {
-		var d Dialer
-		c, err = d.DialContext(ctx, network, server)
-	}
-	if err != nil {
-		return nil, mapErr(err)
-	}
-	return c, nil
-}
-
-func (r *Resolver) lookupHost(ctx context.Context, host string) (addrs []string, err error) {
-	order := systemConf().hostLookupOrder(r, host)
-	if !r.preferGo() && order == hostLookupCgo {
-		if addrs, err, ok := cgoLookupHost(ctx, host); ok {
-			return addrs, err
-		}
-		// cgo not available (or netgo); fall back to Go's DNS resolver
-		order = hostLookupFilesDNS
-	}
-	return r.goLookupHostOrder(ctx, host, order)
-}
-
-func (r *Resolver) lookupIP(ctx context.Context, network, host string) (addrs []IPAddr, err error) {
-	if r.preferGo() {
-		return r.goLookupIP(ctx, network, host)
-	}
-	order := systemConf().hostLookupOrder(r, host)
-	if order == hostLookupCgo {
-		if addrs, err, ok := cgoLookupIP(ctx, network, host); ok {
-			return addrs, err
-		}
-		// cgo not available (or netgo); fall back to Go's DNS resolver
-		order = hostLookupFilesDNS
-	}
-	ips, _, err := r.goLookupIPCNAMEOrder(ctx, network, host, order)
-	return ips, err
-}
-
-func (r *Resolver) lookupPort(ctx context.Context, network, service string) (int, error) {
-	if !r.preferGo() && systemConf().canUseCgo() {
-		if port, err, ok := cgoLookupPort(ctx, network, service); ok {
-			if err != nil {
-				// Issue 18213: if cgo fails, first check to see whether we
-				// have the answer baked-in to the net package.
-				if port, err := goLookupPort(network, service); err == nil {
-					return port, nil
-				}
-			}
-			return port, err
-		}
-	}
-	return goLookupPort(network, service)
-}
-
-func (r *Resolver) lookupCNAME(ctx context.Context, name string) (string, error) {
-	if !r.preferGo() && systemConf().canUseCgo() {
-		if cname, err, ok := cgoLookupCNAME(ctx, name); ok {
-			return cname, err
-		}
-	}
-	return r.goLookupCNAME(ctx, name)
-}
-
-func (r *Resolver) lookupSRV(ctx context.Context, service, proto, name string) (string, []*SRV, error) {
-	var target string
-	if service == "" && proto == "" {
-		target = name
-	} else {
-		target = "_" + service + "._" + proto + "." + name
-	}
-	p, server, err := r.lookup(ctx, target, dnsmessage.TypeSRV)
-	if err != nil {
-		return "", nil, err
-	}
-	var srvs []*SRV
-	var cname dnsmessage.Name
-	for {
-		h, err := p.AnswerHeader()
-		if err == dnsmessage.ErrSectionDone {
-			break
-		}
-		if err != nil {
-			return "", nil, &DNSError{
-				Err:    "cannot unmarshal DNS message",
-				Name:   name,
-				Server: server,
-			}
-		}
-		if h.Type != dnsmessage.TypeSRV {
-			if err := p.SkipAnswer(); err != nil {
-				return "", nil, &DNSError{
-					Err:    "cannot unmarshal DNS message",
-					Name:   name,
-					Server: server,
-				}
-			}
-			continue
-		}
-		if cname.Length == 0 && h.Name.Length != 0 {
-			cname = h.Name
-		}
-		srv, err := p.SRVResource()
-		if err != nil {
-			return "", nil, &DNSError{
-				Err:    "cannot unmarshal DNS message",
-				Name:   name,
-				Server: server,
-			}
-		}
-		srvs = append(srvs, &SRV{Target: srv.Target.String(), Port: srv.Port, Priority: srv.Priority, Weight: srv.Weight})
-	}
-	byPriorityWeight(srvs).sort()
-	return cname.String(), srvs, nil
-}
-
-func (r *Resolver) lookupMX(ctx context.Context, name string) ([]*MX, error) {
-	p, server, err := r.lookup(ctx, name, dnsmessage.TypeMX)
-	if err != nil {
-		return nil, err
-	}
-	var mxs []*MX
-	for {
-		h, err := p.AnswerHeader()
-		if err == dnsmessage.ErrSectionDone {
-			break
-		}
-		if err != nil {
-			return nil, &DNSError{
-				Err:    "cannot unmarshal DNS message",
-				Name:   name,
-				Server: server,
-			}
-		}
-		if h.Type != dnsmessage.TypeMX {
-			if err := p.SkipAnswer(); err != nil {
-				return nil, &DNSError{
-					Err:    "cannot unmarshal DNS message",
-					Name:   name,
-					Server: server,
-				}
-			}
-			continue
-		}
-		mx, err := p.MXResource()
-		if err != nil {
-			return nil, &DNSError{
-				Err:    "cannot unmarshal DNS message",
-				Name:   name,
-				Server: server,
-			}
-		}
-		mxs = append(mxs, &MX{Host: mx.MX.String(), Pref: mx.Pref})
-
-	}
-	byPref(mxs).sort()
-	return mxs, nil
-}
-
-func (r *Resolver) lookupNS(ctx context.Context, name string) ([]*NS, error) {
-	p, server, err := r.lookup(ctx, name, dnsmessage.TypeNS)
-	if err != nil {
-		return nil, err
-	}
-	var nss []*NS
-	for {
-		h, err := p.AnswerHeader()
-		if err == dnsmessage.ErrSectionDone {
-			break
-		}
-		if err != nil {
-			return nil, &DNSError{
-				Err:    "cannot unmarshal DNS message",
-				Name:   name,
-				Server: server,
-			}
-		}
-		if h.Type != dnsmessage.TypeNS {
-			if err := p.SkipAnswer(); err != nil {
-				return nil, &DNSError{
-					Err:    "cannot unmarshal DNS message",
-					Name:   name,
-					Server: server,
-				}
-			}
-			continue
-		}
-		ns, err := p.NSResource()
-		if err != nil {
-			return nil, &DNSError{
-				Err:    "cannot unmarshal DNS message",
-				Name:   name,
-				Server: server,
-			}
-		}
-		nss = append(nss, &NS{Host: ns.NS.String()})
-	}
-	return nss, nil
-}
-
-func (r *Resolver) lookupTXT(ctx context.Context, name string) ([]string, error) {
-	p, server, err := r.lookup(ctx, name, dnsmessage.TypeTXT)
-	if err != nil {
-		return nil, err
-	}
-	var txts []string
-	for {
-		h, err := p.AnswerHeader()
-		if err == dnsmessage.ErrSectionDone {
-			break
-		}
-		if err != nil {
-			return nil, &DNSError{
-				Err:    "cannot unmarshal DNS message",
-				Name:   name,
-				Server: server,
-			}
-		}
-		if h.Type != dnsmessage.TypeTXT {
-			if err := p.SkipAnswer(); err != nil {
-				return nil, &DNSError{
-					Err:    "cannot unmarshal DNS message",
-					Name:   name,
-					Server: server,
-				}
-			}
-			continue
-		}
-		txt, err := p.TXTResource()
-		if err != nil {
-			return nil, &DNSError{
-				Err:    "cannot unmarshal DNS message",
-				Name:   name,
-				Server: server,
-			}
-		}
-		// Multiple strings in one TXT record need to be
-		// concatenated without separator to be consistent
-		// with previous Go resolver.
-		n := 0
-		for _, s := range txt.TXT {
-			n += len(s)
-		}
-		txtJoin := make([]byte, 0, n)
-		for _, s := range txt.TXT {
-			txtJoin = append(txtJoin, s...)
-		}
-		if len(txts) == 0 {
-			txts = make([]string, 0, 1)
-		}
-		txts = append(txts, string(txtJoin))
-	}
-	return txts, nil
-}
-
-func (r *Resolver) lookupAddr(ctx context.Context, addr string) ([]string, error) {
-	if !r.preferGo() && systemConf().canUseCgo() {
-		if ptrs, err, ok := cgoLookupPTR(ctx, addr); ok {
-			return ptrs, err
-		}
-	}
-	return r.goLookupPTR(ctx, addr)
-}
-
-// concurrentThreadsLimit returns the number of threads we permit to
-// run concurrently doing DNS lookups via cgo. A DNS lookup may use a
-// file descriptor so we limit this to less than the number of
-// permitted open files. On some systems, notably Darwin, if
-// getaddrinfo is unable to open a file descriptor it simply returns
-// EAI_NONAME rather than a useful error. Limiting the number of
-// concurrent getaddrinfo calls to less than the permitted number of
-// file descriptors makes that error less likely. We don't bother to
-// apply the same limit to DNS lookups run directly from Go, because
-// there we will return a meaningful "too many open files" error.
-func concurrentThreadsLimit() int {
-	var rlim syscall.Rlimit
-	if err := syscall.Getrlimit(syscall.RLIMIT_NOFILE, &rlim); err != nil {
-		return 500
-	}
-	r := int(rlim.Cur)
-	if r > 500 {
-		r = 500
-	} else if r > 30 {
-		r -= 30
-	}
-	return r
-}
diff --git a/contrib/go/_std_1.18/src/net/mac.go b/contrib/go/_std_1.18/src/net/mac.go
deleted file mode 100644
index 373ac3d7e2..0000000000
--- a/contrib/go/_std_1.18/src/net/mac.go
+++ /dev/null
@@ -1,85 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package net
-
-const hexDigit = "0123456789abcdef"
-
-// A HardwareAddr represents a physical hardware address.
-type HardwareAddr []byte
-
-func (a HardwareAddr) String() string {
-	if len(a) == 0 {
-		return ""
-	}
-	buf := make([]byte, 0, len(a)*3-1)
-	for i, b := range a {
-		if i > 0 {
-			buf = append(buf, ':')
-		}
-		buf = append(buf, hexDigit[b>>4])
-		buf = append(buf, hexDigit[b&0xF])
-	}
-	return string(buf)
-}
-
-// ParseMAC parses s as an IEEE 802 MAC-48, EUI-48, EUI-64, or a 20-octet
-// IP over InfiniBand link-layer address using one of the following formats:
-//	00:00:5e:00:53:01
-//	02:00:5e:10:00:00:00:01
-//	00:00:00:00:fe:80:00:00:00:00:00:00:02:00:5e:10:00:00:00:01
-//	00-00-5e-00-53-01
-//	02-00-5e-10-00-00-00-01
-//	00-00-00-00-fe-80-00-00-00-00-00-00-02-00-5e-10-00-00-00-01
-//	0000.5e00.5301
-//	0200.5e10.0000.0001
-//	0000.0000.fe80.0000.0000.0000.0200.5e10.0000.0001
-func ParseMAC(s string) (hw HardwareAddr, err error) {
-	if len(s) < 14 {
-		goto error
-	}
-
-	if s[2] == ':' || s[2] == '-' {
-		if (len(s)+1)%3 != 0 {
-			goto error
-		}
-		n := (len(s) + 1) / 3
-		if n != 6 && n != 8 && n != 20 {
-			goto error
-		}
-		hw = make(HardwareAddr, n)
-		for x, i := 0, 0; i < n; i++ {
-			var ok bool
-			if hw[i], ok = xtoi2(s[x:], s[2]); !ok {
-				goto error
-			}
-			x += 3
-		}
-	} else if s[4] == '.' {
-		if (len(s)+1)%5 != 0 {
-			goto error
-		}
-		n := 2 * (len(s) + 1) / 5
-		if n != 6 && n != 8 && n != 20 {
-			goto error
-		}
-		hw = make(HardwareAddr, n)
-		for x, i := 0, 0; i < n; i += 2 {
-			var ok bool
-			if hw[i], ok = xtoi2(s[x:x+2], 0); !ok {
-				goto error
-			}
-			if hw[i+1], ok = xtoi2(s[x+2:], s[4]); !ok {
-				goto error
-			}
-			x += 5
-		}
-	} else {
-		goto error
-	}
-	return hw, nil
-
-error:
-	return nil, &AddrError{Err: "invalid MAC address", Addr: s}
-}
diff --git a/contrib/go/_std_1.18/src/net/net.go b/contrib/go/_std_1.18/src/net/net.go
deleted file mode 100644
index d91e743a01..0000000000
--- a/contrib/go/_std_1.18/src/net/net.go
+++ /dev/null
@@ -1,758 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-/*
-Package net provides a portable interface for network I/O, including
-TCP/IP, UDP, domain name resolution, and Unix domain sockets.
-
-Although the package provides access to low-level networking
-primitives, most clients will need only the basic interface provided
-by the Dial, Listen, and Accept functions and the associated
-Conn and Listener interfaces. The crypto/tls package uses
-the same interfaces and similar Dial and Listen functions.
-
-The Dial function connects to a server:
-
-	conn, err := net.Dial("tcp", "golang.org:80")
-	if err != nil {
-		// handle error
-	}
-	fmt.Fprintf(conn, "GET / HTTP/1.0\r\n\r\n")
-	status, err := bufio.NewReader(conn).ReadString('\n')
-	// ...
-
-The Listen function creates servers:
-
-	ln, err := net.Listen("tcp", ":8080")
-	if err != nil {
-		// handle error
-	}
-	for {
-		conn, err := ln.Accept()
-		if err != nil {
-			// handle error
-		}
-		go handleConnection(conn)
-	}
-
-Name Resolution
-
-The method for resolving domain names, whether indirectly with functions like Dial
-or directly with functions like LookupHost and LookupAddr, varies by operating system.
-
-On Unix systems, the resolver has two options for resolving names.
-It can use a pure Go resolver that sends DNS requests directly to the servers
-listed in /etc/resolv.conf, or it can use a cgo-based resolver that calls C
-library routines such as getaddrinfo and getnameinfo.
-
-By default the pure Go resolver is used, because a blocked DNS request consumes
-only a goroutine, while a blocked C call consumes an operating system thread.
-When cgo is available, the cgo-based resolver is used instead under a variety of
-conditions: on systems that do not let programs make direct DNS requests (OS X),
-when the LOCALDOMAIN environment variable is present (even if empty),
-when the RES_OPTIONS or HOSTALIASES environment variable is non-empty,
-when the ASR_CONFIG environment variable is non-empty (OpenBSD only),
-when /etc/resolv.conf or /etc/nsswitch.conf specify the use of features that the
-Go resolver does not implement, and when the name being looked up ends in .local
-or is an mDNS name.
-
-The resolver decision can be overridden by setting the netdns value of the
-GODEBUG environment variable (see package runtime) to go or cgo, as in:
-
-	export GODEBUG=netdns=go    # force pure Go resolver
-	export GODEBUG=netdns=cgo   # force cgo resolver
-
-The decision can also be forced while building the Go source tree
-by setting the netgo or netcgo build tag.
-
-A numeric netdns setting, as in GODEBUG=netdns=1, causes the resolver
-to print debugging information about its decisions.
-To force a particular resolver while also printing debugging information,
-join the two settings by a plus sign, as in GODEBUG=netdns=go+1.
-
-On Plan 9, the resolver always accesses /net/cs and /net/dns.
-
-On Windows, the resolver always uses C library functions, such as GetAddrInfo and DnsQuery.
-
-*/
-package net
-
-import (
-	"context"
-	"errors"
-	"internal/poll"
-	"io"
-	"os"
-	"sync"
-	"syscall"
-	"time"
-)
-
-// netGo and netCgo contain the state of the build tags used
-// to build this binary, and whether cgo is available.
-// conf.go mirrors these into conf for easier testing.
-var (
-	netGo  bool // set true in cgo_stub.go for build tag "netgo" (or no cgo)
-	netCgo bool // set true in conf_netcgo.go for build tag "netcgo"
-)
-
-// Addr represents a network end point address.
-//
-// The two methods Network and String conventionally return strings
-// that can be passed as the arguments to Dial, but the exact form
-// and meaning of the strings is up to the implementation.
-type Addr interface {
-	Network() string // name of the network (for example, "tcp", "udp")
-	String() string  // string form of address (for example, "192.0.2.1:25", "[2001:db8::1]:80")
-}
-
-// Conn is a generic stream-oriented network connection.
-//
-// Multiple goroutines may invoke methods on a Conn simultaneously.
-type Conn interface {
-	// Read reads data from the connection.
-	// Read can be made to time out and return an error after a fixed
-	// time limit; see SetDeadline and SetReadDeadline.
-	Read(b []byte) (n int, err error)
-
-	// Write writes data to the connection.
-	// Write can be made to time out and return an error after a fixed
-	// time limit; see SetDeadline and SetWriteDeadline.
-	Write(b []byte) (n int, err error)
-
-	// Close closes the connection.
-	// Any blocked Read or Write operations will be unblocked and return errors.
-	Close() error
-
-	// LocalAddr returns the local network address, if known.
-	LocalAddr() Addr
-
-	// RemoteAddr returns the remote network address, if known.
-	RemoteAddr() Addr
-
-	// SetDeadline sets the read and write deadlines associated
-	// with the connection. It is equivalent to calling both
-	// SetReadDeadline and SetWriteDeadline.
-	//
-	// A deadline is an absolute time after which I/O operations
-	// fail instead of blocking. The deadline applies to all future
-	// and pending I/O, not just the immediately following call to
-	// Read or Write. After a deadline has been exceeded, the
-	// connection can be refreshed by setting a deadline in the future.
-	//
-	// If the deadline is exceeded a call to Read or Write or to other
-	// I/O methods will return an error that wraps os.ErrDeadlineExceeded.
-	// This can be tested using errors.Is(err, os.ErrDeadlineExceeded).
-	// The error's Timeout method will return true, but note that there
-	// are other possible errors for which the Timeout method will
-	// return true even if the deadline has not been exceeded.
-	//
-	// An idle timeout can be implemented by repeatedly extending
-	// the deadline after successful Read or Write calls.
-	//
-	// A zero value for t means I/O operations will not time out.
-	SetDeadline(t time.Time) error
-
-	// SetReadDeadline sets the deadline for future Read calls
-	// and any currently-blocked Read call.
-	// A zero value for t means Read will not time out.
-	SetReadDeadline(t time.Time) error
-
-	// SetWriteDeadline sets the deadline for future Write calls
-	// and any currently-blocked Write call.
-	// Even if write times out, it may return n > 0, indicating that
-	// some of the data was successfully written.
-	// A zero value for t means Write will not time out.
-	SetWriteDeadline(t time.Time) error
-}
-
-type conn struct {
-	fd *netFD
-}
-
-func (c *conn) ok() bool { return c != nil && c.fd != nil }
-
-// Implementation of the Conn interface.
-
-// Read implements the Conn Read method.
-func (c *conn) Read(b []byte) (int, error) {
-	if !c.ok() {
-		return 0, syscall.EINVAL
-	}
-	n, err := c.fd.Read(b)
-	if err != nil && err != io.EOF {
-		err = &OpError{Op: "read", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
-	}
-	return n, err
-}
-
-// Write implements the Conn Write method.
-func (c *conn) Write(b []byte) (int, error) {
-	if !c.ok() {
-		return 0, syscall.EINVAL
-	}
-	n, err := c.fd.Write(b)
-	if err != nil {
-		err = &OpError{Op: "write", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
-	}
-	return n, err
-}
-
-// Close closes the connection.
-func (c *conn) Close() error {
-	if !c.ok() {
-		return syscall.EINVAL
-	}
-	err := c.fd.Close()
-	if err != nil {
-		err = &OpError{Op: "close", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
-	}
-	return err
-}
-
-// LocalAddr returns the local network address.
-// The Addr returned is shared by all invocations of LocalAddr, so
-// do not modify it.
-func (c *conn) LocalAddr() Addr {
-	if !c.ok() {
-		return nil
-	}
-	return c.fd.laddr
-}
-
-// RemoteAddr returns the remote network address.
-// The Addr returned is shared by all invocations of RemoteAddr, so
-// do not modify it.
-func (c *conn) RemoteAddr() Addr {
-	if !c.ok() {
-		return nil
-	}
-	return c.fd.raddr
-}
-
-// SetDeadline implements the Conn SetDeadline method.
-func (c *conn) SetDeadline(t time.Time) error {
-	if !c.ok() {
-		return syscall.EINVAL
-	}
-	if err := c.fd.SetDeadline(t); err != nil {
-		return &OpError{Op: "set", Net: c.fd.net, Source: nil, Addr: c.fd.laddr, Err: err}
-	}
-	return nil
-}
-
-// SetReadDeadline implements the Conn SetReadDeadline method.
-func (c *conn) SetReadDeadline(t time.Time) error {
-	if !c.ok() {
-		return syscall.EINVAL
-	}
-	if err := c.fd.SetReadDeadline(t); err != nil {
-		return &OpError{Op: "set", Net: c.fd.net, Source: nil, Addr: c.fd.laddr, Err: err}
-	}
-	return nil
-}
-
-// SetWriteDeadline implements the Conn SetWriteDeadline method.
-func (c *conn) SetWriteDeadline(t time.Time) error {
-	if !c.ok() {
-		return syscall.EINVAL
-	}
-	if err := c.fd.SetWriteDeadline(t); err != nil {
-		return &OpError{Op: "set", Net: c.fd.net, Source: nil, Addr: c.fd.laddr, Err: err}
-	}
-	return nil
-}
-
-// SetReadBuffer sets the size of the operating system's
-// receive buffer associated with the connection.
-func (c *conn) SetReadBuffer(bytes int) error {
-	if !c.ok() {
-		return syscall.EINVAL
-	}
-	if err := setReadBuffer(c.fd, bytes); err != nil {
-		return &OpError{Op: "set", Net: c.fd.net, Source: nil, Addr: c.fd.laddr, Err: err}
-	}
-	return nil
-}
-
-// SetWriteBuffer sets the size of the operating system's
-// transmit buffer associated with the connection.
-func (c *conn) SetWriteBuffer(bytes int) error {
-	if !c.ok() {
-		return syscall.EINVAL
-	}
-	if err := setWriteBuffer(c.fd, bytes); err != nil {
-		return &OpError{Op: "set", Net: c.fd.net, Source: nil, Addr: c.fd.laddr, Err: err}
-	}
-	return nil
-}
-
-// File returns a copy of the underlying os.File.
-// It is the caller's responsibility to close f when finished.
-// Closing c does not affect f, and closing f does not affect c.
-//
-// The returned os.File's file descriptor is different from the connection's.
-// Attempting to change properties of the original using this duplicate
-// may or may not have the desired effect.
-func (c *conn) File() (f *os.File, err error) {
-	f, err = c.fd.dup()
-	if err != nil {
-		err = &OpError{Op: "file", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
-	}
-	return
-}
-
-// PacketConn is a generic packet-oriented network connection.
-//
-// Multiple goroutines may invoke methods on a PacketConn simultaneously.
-type PacketConn interface {
-	// ReadFrom reads a packet from the connection,
-	// copying the payload into p. It returns the number of
-	// bytes copied into p and the return address that
-	// was on the packet.
-	// It returns the number of bytes read (0 <= n <= len(p))
-	// and any error encountered. Callers should always process
-	// the n > 0 bytes returned before considering the error err.
-	// ReadFrom can be made to time out and return an error after a
-	// fixed time limit; see SetDeadline and SetReadDeadline.
-	ReadFrom(p []byte) (n int, addr Addr, err error)
-
-	// WriteTo writes a packet with payload p to addr.
-	// WriteTo can be made to time out and return an Error after a
-	// fixed time limit; see SetDeadline and SetWriteDeadline.
-	// On packet-oriented connections, write timeouts are rare.
-	WriteTo(p []byte, addr Addr) (n int, err error)
-
-	// Close closes the connection.
-	// Any blocked ReadFrom or WriteTo operations will be unblocked and return errors.
-	Close() error
-
-	// LocalAddr returns the local network address, if known.
-	LocalAddr() Addr
-
-	// SetDeadline sets the read and write deadlines associated
-	// with the connection. It is equivalent to calling both
-	// SetReadDeadline and SetWriteDeadline.
-	//
-	// A deadline is an absolute time after which I/O operations
-	// fail instead of blocking. The deadline applies to all future
-	// and pending I/O, not just the immediately following call to
-	// Read or Write. After a deadline has been exceeded, the
-	// connection can be refreshed by setting a deadline in the future.
-	//
-	// If the deadline is exceeded a call to Read or Write or to other
-	// I/O methods will return an error that wraps os.ErrDeadlineExceeded.
-	// This can be tested using errors.Is(err, os.ErrDeadlineExceeded).
-	// The error's Timeout method will return true, but note that there
-	// are other possible errors for which the Timeout method will
-	// return true even if the deadline has not been exceeded.
-	//
-	// An idle timeout can be implemented by repeatedly extending
-	// the deadline after successful ReadFrom or WriteTo calls.
-	//
-	// A zero value for t means I/O operations will not time out.
-	SetDeadline(t time.Time) error
-
-	// SetReadDeadline sets the deadline for future ReadFrom calls
-	// and any currently-blocked ReadFrom call.
-	// A zero value for t means ReadFrom will not time out.
-	SetReadDeadline(t time.Time) error
-
-	// SetWriteDeadline sets the deadline for future WriteTo calls
-	// and any currently-blocked WriteTo call.
-	// Even if write times out, it may return n > 0, indicating that
-	// some of the data was successfully written.
-	// A zero value for t means WriteTo will not time out.
-	SetWriteDeadline(t time.Time) error
-}
-
-var listenerBacklogCache struct {
-	sync.Once
-	val int
-}
-
-// listenerBacklog is a caching wrapper around maxListenerBacklog.
-func listenerBacklog() int {
-	listenerBacklogCache.Do(func() { listenerBacklogCache.val = maxListenerBacklog() })
-	return listenerBacklogCache.val
-}
-
-// A Listener is a generic network listener for stream-oriented protocols.
-//
-// Multiple goroutines may invoke methods on a Listener simultaneously.
-type Listener interface {
-	// Accept waits for and returns the next connection to the listener.
-	Accept() (Conn, error)
-
-	// Close closes the listener.
-	// Any blocked Accept operations will be unblocked and return errors.
-	Close() error
-
-	// Addr returns the listener's network address.
-	Addr() Addr
-}
-
-// An Error represents a network error.
-type Error interface {
-	error
-	Timeout() bool // Is the error a timeout?
-
-	// Deprecated: Temporary errors are not well-defined.
-	// Most "temporary" errors are timeouts, and the few exceptions are surprising.
-	// Do not use this method.
-	Temporary() bool
-}
-
-// Various errors contained in OpError.
-var (
-	// For connection setup operations.
-	errNoSuitableAddress = errors.New("no suitable address found")
-
-	// For connection setup and write operations.
-	errMissingAddress = errors.New("missing address")
-
-	// For both read and write operations.
-	errCanceled         = errors.New("operation was canceled")
-	ErrWriteToConnected = errors.New("use of WriteTo with pre-connected connection")
-)
-
-// mapErr maps from the context errors to the historical internal net
-// error values.
-//
-// TODO(bradfitz): get rid of this after adjusting tests and making
-// context.DeadlineExceeded implement net.Error?
-func mapErr(err error) error {
-	switch err {
-	case context.Canceled:
-		return errCanceled
-	case context.DeadlineExceeded:
-		return errTimeout
-	default:
-		return err
-	}
-}
-
-// OpError is the error type usually returned by functions in the net
-// package. It describes the operation, network type, and address of
-// an error.
-type OpError struct {
-	// Op is the operation which caused the error, such as
-	// "read" or "write".
-	Op string
-
-	// Net is the network type on which this error occurred,
-	// such as "tcp" or "udp6".
-	Net string
-
-	// For operations involving a remote network connection, like
-	// Dial, Read, or Write, Source is the corresponding local
-	// network address.
-	Source Addr
-
-	// Addr is the network address for which this error occurred.
-	// For local operations, like Listen or SetDeadline, Addr is
-	// the address of the local endpoint being manipulated.
-	// For operations involving a remote network connection, like
-	// Dial, Read, or Write, Addr is the remote address of that
-	// connection.
-	Addr Addr
-
-	// Err is the error that occurred during the operation.
-	// The Error method panics if the error is nil.
-	Err error
-}
-
-func (e *OpError) Unwrap() error { return e.Err }
-
-func (e *OpError) Error() string {
-	if e == nil {
-		return "<nil>"
-	}
-	s := e.Op
-	if e.Net != "" {
-		s += " " + e.Net
-	}
-	if e.Source != nil {
-		s += " " + e.Source.String()
-	}
-	if e.Addr != nil {
-		if e.Source != nil {
-			s += "->"
-		} else {
-			s += " "
-		}
-		s += e.Addr.String()
-	}
-	s += ": " + e.Err.Error()
-	return s
-}
-
-var (
-	// aLongTimeAgo is a non-zero time, far in the past, used for
-	// immediate cancellation of dials.
-	aLongTimeAgo = time.Unix(1, 0)
-
-	// nonDeadline and noCancel are just zero values for
-	// readability with functions taking too many parameters.
-	noDeadline = time.Time{}
-	noCancel   = (chan struct{})(nil)
-)
-
-type timeout interface {
-	Timeout() bool
-}
-
-func (e *OpError) Timeout() bool {
-	if ne, ok := e.Err.(*os.SyscallError); ok {
-		t, ok := ne.Err.(timeout)
-		return ok && t.Timeout()
-	}
-	t, ok := e.Err.(timeout)
-	return ok && t.Timeout()
-}
-
-type temporary interface {
-	Temporary() bool
-}
-
-func (e *OpError) Temporary() bool {
-	// Treat ECONNRESET and ECONNABORTED as temporary errors when
-	// they come from calling accept. See issue 6163.
-	if e.Op == "accept" && isConnError(e.Err) {
-		return true
-	}
-
-	if ne, ok := e.Err.(*os.SyscallError); ok {
-		t, ok := ne.Err.(temporary)
-		return ok && t.Temporary()
-	}
-	t, ok := e.Err.(temporary)
-	return ok && t.Temporary()
-}
-
-// A ParseError is the error type of literal network address parsers.
-type ParseError struct {
-	// Type is the type of string that was expected, such as
-	// "IP address", "CIDR address".
-	Type string
-
-	// Text is the malformed text string.
-	Text string
-}
-
-func (e *ParseError) Error() string { return "invalid " + e.Type + ": " + e.Text }
-
-func (e *ParseError) Timeout() bool   { return false }
-func (e *ParseError) Temporary() bool { return false }
-
-type AddrError struct {
-	Err  string
-	Addr string
-}
-
-func (e *AddrError) Error() string {
-	if e == nil {
-		return "<nil>"
-	}
-	s := e.Err
-	if e.Addr != "" {
-		s = "address " + e.Addr + ": " + s
-	}
-	return s
-}
-
-func (e *AddrError) Timeout() bool   { return false }
-func (e *AddrError) Temporary() bool { return false }
-
-type UnknownNetworkError string
-
-func (e UnknownNetworkError) Error() string   { return "unknown network " + string(e) }
-func (e UnknownNetworkError) Timeout() bool   { return false }
-func (e UnknownNetworkError) Temporary() bool { return false }
-
-type InvalidAddrError string
-
-func (e InvalidAddrError) Error() string   { return string(e) }
-func (e InvalidAddrError) Timeout() bool   { return false }
-func (e InvalidAddrError) Temporary() bool { return false }
-
-// errTimeout exists to return the historical "i/o timeout" string
-// for context.DeadlineExceeded. See mapErr.
-// It is also used when Dialer.Deadline is exceeded.
-//
-// TODO(iant): We could consider changing this to os.ErrDeadlineExceeded
-// in the future, but note that that would conflict with the TODO
-// at mapErr that suggests changing it to context.DeadlineExceeded.
-var errTimeout error = &timeoutError{}
-
-type timeoutError struct{}
-
-func (e *timeoutError) Error() string   { return "i/o timeout" }
-func (e *timeoutError) Timeout() bool   { return true }
-func (e *timeoutError) Temporary() bool { return true }
-
-// DNSConfigError represents an error reading the machine's DNS configuration.
-// (No longer used; kept for compatibility.)
-type DNSConfigError struct {
-	Err error
-}
-
-func (e *DNSConfigError) Unwrap() error   { return e.Err }
-func (e *DNSConfigError) Error() string   { return "error reading DNS config: " + e.Err.Error() }
-func (e *DNSConfigError) Timeout() bool   { return false }
-func (e *DNSConfigError) Temporary() bool { return false }
-
-// Various errors contained in DNSError.
-var (
-	errNoSuchHost = errors.New("no such host")
-)
-
-// DNSError represents a DNS lookup error.
-type DNSError struct {
-	Err         string // description of the error
-	Name        string // name looked for
-	Server      string // server used
-	IsTimeout   bool   // if true, timed out; not all timeouts set this
-	IsTemporary bool   // if true, error is temporary; not all errors set this
-	IsNotFound  bool   // if true, host could not be found
-}
-
-func (e *DNSError) Error() string {
-	if e == nil {
-		return "<nil>"
-	}
-	s := "lookup " + e.Name
-	if e.Server != "" {
-		s += " on " + e.Server
-	}
-	s += ": " + e.Err
-	return s
-}
-
-// Timeout reports whether the DNS lookup is known to have timed out.
-// This is not always known; a DNS lookup may fail due to a timeout
-// and return a DNSError for which Timeout returns false.
-func (e *DNSError) Timeout() bool { return e.IsTimeout }
-
-// Temporary reports whether the DNS error is known to be temporary.
-// This is not always known; a DNS lookup may fail due to a temporary
-// error and return a DNSError for which Temporary returns false.
-func (e *DNSError) Temporary() bool { return e.IsTimeout || e.IsTemporary }
-
-// errClosed exists just so that the docs for ErrClosed don't mention
-// the internal package poll.
-var errClosed = poll.ErrNetClosing
-
-// ErrClosed is the error returned by an I/O call on a network
-// connection that has already been closed, or that is closed by
-// another goroutine before the I/O is completed. This may be wrapped
-// in another error, and should normally be tested using
-// errors.Is(err, net.ErrClosed).
-var ErrClosed error = errClosed
-
-type writerOnly struct {
-	io.Writer
-}
-
-// Fallback implementation of io.ReaderFrom's ReadFrom, when sendfile isn't
-// applicable.
-func genericReadFrom(w io.Writer, r io.Reader) (n int64, err error) {
-	// Use wrapper to hide existing r.ReadFrom from io.Copy.
-	return io.Copy(writerOnly{w}, r)
-}
-
-// Limit the number of concurrent cgo-using goroutines, because
-// each will block an entire operating system thread. The usual culprit
-// is resolving many DNS names in separate goroutines but the DNS
-// server is not responding. Then the many lookups each use a different
-// thread, and the system or the program runs out of threads.
-
-var threadLimit chan struct{}
-
-var threadOnce sync.Once
-
-func acquireThread() {
-	threadOnce.Do(func() {
-		threadLimit = make(chan struct{}, concurrentThreadsLimit())
-	})
-	threadLimit <- struct{}{}
-}
-
-func releaseThread() {
-	<-threadLimit
-}
-
-// buffersWriter is the interface implemented by Conns that support a
-// "writev"-like batch write optimization.
-// writeBuffers should fully consume and write all chunks from the
-// provided Buffers, else it should report a non-nil error.
-type buffersWriter interface {
-	writeBuffers(*Buffers) (int64, error)
-}
-
-// Buffers contains zero or more runs of bytes to write.
-//
-// On certain machines, for certain types of connections, this is
-// optimized into an OS-specific batch write operation (such as
-// "writev").
-type Buffers [][]byte
-
-var (
-	_ io.WriterTo = (*Buffers)(nil)
-	_ io.Reader   = (*Buffers)(nil)
-)
-
-// WriteTo writes contents of the buffers to w.
-//
-// WriteTo implements io.WriterTo for Buffers.
-//
-// WriteTo modifies the slice v as well as v[i] for 0 <= i < len(v),
-// but does not modify v[i][j] for any i, j.
-func (v *Buffers) WriteTo(w io.Writer) (n int64, err error) {
-	if wv, ok := w.(buffersWriter); ok {
-		return wv.writeBuffers(v)
-	}
-	for _, b := range *v {
-		nb, err := w.Write(b)
-		n += int64(nb)
-		if err != nil {
-			v.consume(n)
-			return n, err
-		}
-	}
-	v.consume(n)
-	return n, nil
-}
-
-// Read from the buffers.
-//
-// Read implements io.Reader for Buffers.
-//
-// Read modifies the slice v as well as v[i] for 0 <= i < len(v),
-// but does not modify v[i][j] for any i, j.
-func (v *Buffers) Read(p []byte) (n int, err error) {
-	for len(p) > 0 && len(*v) > 0 {
-		n0 := copy(p, (*v)[0])
-		v.consume(int64(n0))
-		p = p[n0:]
-		n += n0
-	}
-	if len(*v) == 0 {
-		err = io.EOF
-	}
-	return
-}
-
-func (v *Buffers) consume(n int64) {
-	for len(*v) > 0 {
-		ln0 := int64(len((*v)[0]))
-		if ln0 > n {
-			(*v)[0] = (*v)[0][n:]
-			return
-		}
-		n -= ln0
-		(*v)[0] = nil
-		*v = (*v)[1:]
-	}
-}
diff --git a/contrib/go/_std_1.18/src/net/netip/netip.go b/contrib/go/_std_1.18/src/net/netip/netip.go
deleted file mode 100644
index f27984ab57..0000000000
--- a/contrib/go/_std_1.18/src/net/netip/netip.go
+++ /dev/null
@@ -1,1498 +0,0 @@
-// Copyright 2020 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package netip defines an IP address type that's a small value type.
-// Building on that Addr type, the package also defines AddrPort (an
-// IP address and a port), and Prefix (an IP address and a bit length
-// prefix).
-//
-// Compared to the net.IP type, this package's Addr type takes less
-// memory, is immutable, and is comparable (supports == and being a
-// map key).
-package netip
-
-import (
-	"errors"
-	"math"
-	"strconv"
-
-	"internal/bytealg"
-	"internal/intern"
-	"internal/itoa"
-)
-
-// Sizes: (64-bit)
-//   net.IP:     24 byte slice header + {4, 16} = 28 to 40 bytes
-//   net.IPAddr: 40 byte slice header + {4, 16} = 44 to 56 bytes + zone length
-//   netip.Addr: 24 bytes (zone is per-name singleton, shared across all users)
-
-// Addr represents an IPv4 or IPv6 address (with or without a scoped
-// addressing zone), similar to net.IP or net.IPAddr.
-//
-// Unlike net.IP or net.IPAddr, Addr is a comparable value
-// type (it supports == and can be a map key) and is immutable.
-//
-// The zero Addr is not a valid IP address.
-// Addr{} is distinct from both 0.0.0.0 and ::.
-type Addr struct {
-	// addr is the hi and lo bits of an IPv6 address. If z==z4,
-	// hi and lo contain the IPv4-mapped IPv6 address.
-	//
-	// hi and lo are constructed by interpreting a 16-byte IPv6
-	// address as a big-endian 128-bit number. The most significant
-	// bits of that number go into hi, the rest into lo.
-	//
-	// For example, 0011:2233:4455:6677:8899:aabb:ccdd:eeff is stored as:
-	//  addr.hi = 0x0011223344556677
-	//  addr.lo = 0x8899aabbccddeeff
-	//
-	// We store IPs like this, rather than as [16]byte, because it
-	// turns most operations on IPs into arithmetic and bit-twiddling
-	// operations on 64-bit registers, which is much faster than
-	// bytewise processing.
-	addr uint128
-
-	// z is a combination of the address family and the IPv6 zone.
-	//
-	// nil means invalid IP address (for a zero Addr).
-	// z4 means an IPv4 address.
-	// z6noz means an IPv6 address without a zone.
-	//
-	// Otherwise it's the interned zone name string.
-	z *intern.Value
-}
-
-// z0, z4, and z6noz are sentinel IP.z values.
-// See the IP type's field docs.
-var (
-	z0    = (*intern.Value)(nil)
-	z4    = new(intern.Value)
-	z6noz = new(intern.Value)
-)
-
-// IPv6LinkLocalAllNodes returns the IPv6 link-local all nodes multicast
-// address ff02::1.
-func IPv6LinkLocalAllNodes() Addr { return AddrFrom16([16]byte{0: 0xff, 1: 0x02, 15: 0x01}) }
-
-// IPv6Unspecified returns the IPv6 unspecified address "::".
-func IPv6Unspecified() Addr { return Addr{z: z6noz} }
-
-// IPv4Unspecified returns the IPv4 unspecified address "0.0.0.0".
-func IPv4Unspecified() Addr { return AddrFrom4([4]byte{}) }
-
-// AddrFrom4 returns the address of the IPv4 address given by the bytes in addr.
-func AddrFrom4(addr [4]byte) Addr {
-	return Addr{
-		addr: uint128{0, 0xffff00000000 | uint64(addr[0])<<24 | uint64(addr[1])<<16 | uint64(addr[2])<<8 | uint64(addr[3])},
-		z:    z4,
-	}
-}
-
-// AddrFrom16 returns the IPv6 address given by the bytes in addr.
-// An IPv6-mapped IPv4 address is left as an IPv6 address.
-// (Use Unmap to convert them if needed.)
-func AddrFrom16(addr [16]byte) Addr {
-	return Addr{
-		addr: uint128{
-			beUint64(addr[:8]),
-			beUint64(addr[8:]),
-		},
-		z: z6noz,
-	}
-}
-
-// ipv6Slice is like IPv6Raw, but operates on a 16-byte slice. Assumes
-// slice is 16 bytes, caller must enforce this.
-func ipv6Slice(addr []byte) Addr {
-	return Addr{
-		addr: uint128{
-			beUint64(addr[:8]),
-			beUint64(addr[8:]),
-		},
-		z: z6noz,
-	}
-}
-
-// ParseAddr parses s as an IP address, returning the result. The string
-// s can be in dotted decimal ("192.0.2.1"), IPv6 ("2001:db8::68"),
-// or IPv6 with a scoped addressing zone ("fe80::1cc0:3e8c:119f:c2e1%ens18").
-func ParseAddr(s string) (Addr, error) {
-	for i := 0; i < len(s); i++ {
-		switch s[i] {
-		case '.':
-			return parseIPv4(s)
-		case ':':
-			return parseIPv6(s)
-		case '%':
-			// Assume that this was trying to be an IPv6 address with
-			// a zone specifier, but the address is missing.
-			return Addr{}, parseAddrError{in: s, msg: "missing IPv6 address"}
-		}
-	}
-	return Addr{}, parseAddrError{in: s, msg: "unable to parse IP"}
-}
-
-// MustParseAddr calls ParseAddr(s) and panics on error.
-// It is intended for use in tests with hard-coded strings.
-func MustParseAddr(s string) Addr {
-	ip, err := ParseAddr(s)
-	if err != nil {
-		panic(err)
-	}
-	return ip
-}
-
-type parseAddrError struct {
-	in  string // the string given to ParseAddr
-	msg string // an explanation of the parse failure
-	at  string // optionally, the unparsed portion of in at which the error occurred.
-}
-
-func (err parseAddrError) Error() string {
-	q := strconv.Quote
-	if err.at != "" {
-		return "ParseAddr(" + q(err.in) + "): " + err.msg + " (at " + q(err.at) + ")"
-	}
-	return "ParseAddr(" + q(err.in) + "): " + err.msg
-}
-
-// parseIPv4 parses s as an IPv4 address (in form "192.168.0.1").
-func parseIPv4(s string) (ip Addr, err error) {
-	var fields [4]uint8
-	var val, pos int
-	var digLen int // number of digits in current octet
-	for i := 0; i < len(s); i++ {
-		if s[i] >= '0' && s[i] <= '9' {
-			if digLen == 1 && val == 0 {
-				return Addr{}, parseAddrError{in: s, msg: "IPv4 field has octet with leading zero"}
-			}
-			val = val*10 + int(s[i]) - '0'
-			digLen++
-			if val > 255 {
-				return Addr{}, parseAddrError{in: s, msg: "IPv4 field has value >255"}
-			}
-		} else if s[i] == '.' {
-			// .1.2.3
-			// 1.2.3.
-			// 1..2.3
-			if i == 0 || i == len(s)-1 || s[i-1] == '.' {
-				return Addr{}, parseAddrError{in: s, msg: "IPv4 field must have at least one digit", at: s[i:]}
-			}
-			// 1.2.3.4.5
-			if pos == 3 {
-				return Addr{}, parseAddrError{in: s, msg: "IPv4 address too long"}
-			}
-			fields[pos] = uint8(val)
-			pos++
-			val = 0
-			digLen = 0
-		} else {
-			return Addr{}, parseAddrError{in: s, msg: "unexpected character", at: s[i:]}
-		}
-	}
-	if pos < 3 {
-		return Addr{}, parseAddrError{in: s, msg: "IPv4 address too short"}
-	}
-	fields[3] = uint8(val)
-	return AddrFrom4(fields), nil
-}
-
-// parseIPv6 parses s as an IPv6 address (in form "2001:db8::68").
-func parseIPv6(in string) (Addr, error) {
-	s := in
-
-	// Split off the zone right from the start. Yes it's a second scan
-	// of the string, but trying to handle it inline makes a bunch of
-	// other inner loop conditionals more expensive, and it ends up
-	// being slower.
-	zone := ""
-	i := bytealg.IndexByteString(s, '%')
-	if i != -1 {
-		s, zone = s[:i], s[i+1:]
-		if zone == "" {
-			// Not allowed to have an empty zone if explicitly specified.
-			return Addr{}, parseAddrError{in: in, msg: "zone must be a non-empty string"}
-		}
-	}
-
-	var ip [16]byte
-	ellipsis := -1 // position of ellipsis in ip
-
-	// Might have leading ellipsis
-	if len(s) >= 2 && s[0] == ':' && s[1] == ':' {
-		ellipsis = 0
-		s = s[2:]
-		// Might be only ellipsis
-		if len(s) == 0 {
-			return IPv6Unspecified().WithZone(zone), nil
-		}
-	}
-
-	// Loop, parsing hex numbers followed by colon.
-	i = 0
-	for i < 16 {
-		// Hex number. Similar to parseIPv4, inlining the hex number
-		// parsing yields a significant performance increase.
-		off := 0
-		acc := uint32(0)
-		for ; off < len(s); off++ {
-			c := s[off]
-			if c >= '0' && c <= '9' {
-				acc = (acc << 4) + uint32(c-'0')
-			} else if c >= 'a' && c <= 'f' {
-				acc = (acc << 4) + uint32(c-'a'+10)
-			} else if c >= 'A' && c <= 'F' {
-				acc = (acc << 4) + uint32(c-'A'+10)
-			} else {
-				break
-			}
-			if acc > math.MaxUint16 {
-				// Overflow, fail.
-				return Addr{}, parseAddrError{in: in, msg: "IPv6 field has value >=2^16", at: s}
-			}
-		}
-		if off == 0 {
-			// No digits found, fail.
-			return Addr{}, parseAddrError{in: in, msg: "each colon-separated field must have at least one digit", at: s}
-		}
-
-		// If followed by dot, might be in trailing IPv4.
-		if off < len(s) && s[off] == '.' {
-			if ellipsis < 0 && i != 12 {
-				// Not the right place.
-				return Addr{}, parseAddrError{in: in, msg: "embedded IPv4 address must replace the final 2 fields of the address", at: s}
-			}
-			if i+4 > 16 {
-				// Not enough room.
-				return Addr{}, parseAddrError{in: in, msg: "too many hex fields to fit an embedded IPv4 at the end of the address", at: s}
-			}
-			// TODO: could make this a bit faster by having a helper
-			// that parses to a [4]byte, and have both parseIPv4 and
-			// parseIPv6 use it.
-			ip4, err := parseIPv4(s)
-			if err != nil {
-				return Addr{}, parseAddrError{in: in, msg: err.Error(), at: s}
-			}
-			ip[i] = ip4.v4(0)
-			ip[i+1] = ip4.v4(1)
-			ip[i+2] = ip4.v4(2)
-			ip[i+3] = ip4.v4(3)
-			s = ""
-			i += 4
-			break
-		}
-
-		// Save this 16-bit chunk.
-		ip[i] = byte(acc >> 8)
-		ip[i+1] = byte(acc)
-		i += 2
-
-		// Stop at end of string.
-		s = s[off:]
-		if len(s) == 0 {
-			break
-		}
-
-		// Otherwise must be followed by colon and more.
-		if s[0] != ':' {
-			return Addr{}, parseAddrError{in: in, msg: "unexpected character, want colon", at: s}
-		} else if len(s) == 1 {
-			return Addr{}, parseAddrError{in: in, msg: "colon must be followed by more characters", at: s}
-		}
-		s = s[1:]
-
-		// Look for ellipsis.
-		if s[0] == ':' {
-			if ellipsis >= 0 { // already have one
-				return Addr{}, parseAddrError{in: in, msg: "multiple :: in address", at: s}
-			}
-			ellipsis = i
-			s = s[1:]
-			if len(s) == 0 { // can be at end
-				break
-			}
-		}
-	}
-
-	// Must have used entire string.
-	if len(s) != 0 {
-		return Addr{}, parseAddrError{in: in, msg: "trailing garbage after address", at: s}
-	}
-
-	// If didn't parse enough, expand ellipsis.
-	if i < 16 {
-		if ellipsis < 0 {
-			return Addr{}, parseAddrError{in: in, msg: "address string too short"}
-		}
-		n := 16 - i
-		for j := i - 1; j >= ellipsis; j-- {
-			ip[j+n] = ip[j]
-		}
-		for j := ellipsis + n - 1; j >= ellipsis; j-- {
-			ip[j] = 0
-		}
-	} else if ellipsis >= 0 {
-		// Ellipsis must represent at least one 0 group.
-		return Addr{}, parseAddrError{in: in, msg: "the :: must expand to at least one field of zeros"}
-	}
-	return AddrFrom16(ip).WithZone(zone), nil
-}
-
-// AddrFromSlice parses the 4- or 16-byte byte slice as an IPv4 or IPv6 address.
-// Note that a net.IP can be passed directly as the []byte argument.
-// If slice's length is not 4 or 16, AddrFromSlice returns Addr{}, false.
-func AddrFromSlice(slice []byte) (ip Addr, ok bool) {
-	switch len(slice) {
-	case 4:
-		return AddrFrom4(*(*[4]byte)(slice)), true
-	case 16:
-		return ipv6Slice(slice), true
-	}
-	return Addr{}, false
-}
-
-// v4 returns the i'th byte of ip. If ip is not an IPv4, v4 returns
-// unspecified garbage.
-func (ip Addr) v4(i uint8) uint8 {
-	return uint8(ip.addr.lo >> ((3 - i) * 8))
-}
-
-// v6 returns the i'th byte of ip. If ip is an IPv4 address, this
-// accesses the IPv4-mapped IPv6 address form of the IP.
-func (ip Addr) v6(i uint8) uint8 {
-	return uint8(*(ip.addr.halves()[(i/8)%2]) >> ((7 - i%8) * 8))
-}
-
-// v6u16 returns the i'th 16-bit word of ip. If ip is an IPv4 address,
-// this accesses the IPv4-mapped IPv6 address form of the IP.
-func (ip Addr) v6u16(i uint8) uint16 {
-	return uint16(*(ip.addr.halves()[(i/4)%2]) >> ((3 - i%4) * 16))
-}
-
-// isZero reports whether ip is the zero value of the IP type.
-// The zero value is not a valid IP address of any type.
-//
-// Note that "0.0.0.0" and "::" are not the zero value. Use IsUnspecified to
-// check for these values instead.
-func (ip Addr) isZero() bool {
-	// Faster than comparing ip == Addr{}, but effectively equivalent,
-	// as there's no way to make an IP with a nil z from this package.
-	return ip.z == z0
-}
-
-// IsValid reports whether the Addr is an initialized address (not the zero Addr).
-//
-// Note that "0.0.0.0" and "::" are both valid values.
-func (ip Addr) IsValid() bool { return ip.z != z0 }
-
-// BitLen returns the number of bits in the IP address:
-// 128 for IPv6, 32 for IPv4, and 0 for the zero Addr.
-//
-// Note that IPv4-mapped IPv6 addresses are considered IPv6 addresses
-// and therefore have bit length 128.
-func (ip Addr) BitLen() int {
-	switch ip.z {
-	case z0:
-		return 0
-	case z4:
-		return 32
-	}
-	return 128
-}
-
-// Zone returns ip's IPv6 scoped addressing zone, if any.
-func (ip Addr) Zone() string {
-	if ip.z == nil {
-		return ""
-	}
-	zone, _ := ip.z.Get().(string)
-	return zone
-}
-
-// Compare returns an integer comparing two IPs.
-// The result will be 0 if ip == ip2, -1 if ip < ip2, and +1 if ip > ip2.
-// The definition of "less than" is the same as the Less method.
-func (ip Addr) Compare(ip2 Addr) int {
-	f1, f2 := ip.BitLen(), ip2.BitLen()
-	if f1 < f2 {
-		return -1
-	}
-	if f1 > f2 {
-		return 1
-	}
-	hi1, hi2 := ip.addr.hi, ip2.addr.hi
-	if hi1 < hi2 {
-		return -1
-	}
-	if hi1 > hi2 {
-		return 1
-	}
-	lo1, lo2 := ip.addr.lo, ip2.addr.lo
-	if lo1 < lo2 {
-		return -1
-	}
-	if lo1 > lo2 {
-		return 1
-	}
-	if ip.Is6() {
-		za, zb := ip.Zone(), ip2.Zone()
-		if za < zb {
-			return -1
-		}
-		if za > zb {
-			return 1
-		}
-	}
-	return 0
-}
-
-// Less reports whether ip sorts before ip2.
-// IP addresses sort first by length, then their address.
-// IPv6 addresses with zones sort just after the same address without a zone.
-func (ip Addr) Less(ip2 Addr) bool { return ip.Compare(ip2) == -1 }
-
-func (ip Addr) lessOrEq(ip2 Addr) bool { return ip.Compare(ip2) <= 0 }
-
-// Is4 reports whether ip is an IPv4 address.
-//
-// It returns false for IP4-mapped IPv6 addresses. See IP.Unmap.
-func (ip Addr) Is4() bool {
-	return ip.z == z4
-}
-
-// Is4In6 reports whether ip is an IPv4-mapped IPv6 address.
-func (ip Addr) Is4In6() bool {
-	return ip.Is6() && ip.addr.hi == 0 && ip.addr.lo>>32 == 0xffff
-}
-
-// Is6 reports whether ip is an IPv6 address, including IPv4-mapped
-// IPv6 addresses.
-func (ip Addr) Is6() bool {
-	return ip.z != z0 && ip.z != z4
-}
-
-// Unmap returns ip with any IPv4-mapped IPv6 address prefix removed.
-//
-// That is, if ip is an IPv6 address wrapping an IPv4 adddress, it
-// returns the wrapped IPv4 address. Otherwise it returns ip unmodified.
-func (ip Addr) Unmap() Addr {
-	if ip.Is4In6() {
-		ip.z = z4
-	}
-	return ip
-}
-
-// WithZone returns an IP that's the same as ip but with the provided
-// zone. If zone is empty, the zone is removed. If ip is an IPv4
-// address, WithZone is a no-op and returns ip unchanged.
-func (ip Addr) WithZone(zone string) Addr {
-	if !ip.Is6() {
-		return ip
-	}
-	if zone == "" {
-		ip.z = z6noz
-		return ip
-	}
-	ip.z = intern.GetByString(zone)
-	return ip
-}
-
-// withoutZone unconditionally strips the zone from IP.
-// It's similar to WithZone, but small enough to be inlinable.
-func (ip Addr) withoutZone() Addr {
-	if !ip.Is6() {
-		return ip
-	}
-	ip.z = z6noz
-	return ip
-}
-
-// hasZone reports whether IP has an IPv6 zone.
-func (ip Addr) hasZone() bool {
-	return ip.z != z0 && ip.z != z4 && ip.z != z6noz
-}
-
-// IsLinkLocalUnicast reports whether ip is a link-local unicast address.
-func (ip Addr) IsLinkLocalUnicast() bool {
-	// Dynamic Configuration of IPv4 Link-Local Addresses
-	// https://datatracker.ietf.org/doc/html/rfc3927#section-2.1
-	if ip.Is4() {
-		return ip.v4(0) == 169 && ip.v4(1) == 254
-	}
-	// IP Version 6 Addressing Architecture (2.4 Address Type Identification)
-	// https://datatracker.ietf.org/doc/html/rfc4291#section-2.4
-	if ip.Is6() {
-		return ip.v6u16(0)&0xffc0 == 0xfe80
-	}
-	return false // zero value
-}
-
-// IsLoopback reports whether ip is a loopback address.
-func (ip Addr) IsLoopback() bool {
-	// Requirements for Internet Hosts -- Communication Layers (3.2.1.3 Addressing)
-	// https://datatracker.ietf.org/doc/html/rfc1122#section-3.2.1.3
-	if ip.Is4() {
-		return ip.v4(0) == 127
-	}
-	// IP Version 6 Addressing Architecture (2.4 Address Type Identification)
-	// https://datatracker.ietf.org/doc/html/rfc4291#section-2.4
-	if ip.Is6() {
-		return ip.addr.hi == 0 && ip.addr.lo == 1
-	}
-	return false // zero value
-}
-
-// IsMulticast reports whether ip is a multicast address.
-func (ip Addr) IsMulticast() bool {
-	// Host Extensions for IP Multicasting (4. HOST GROUP ADDRESSES)
-	// https://datatracker.ietf.org/doc/html/rfc1112#section-4
-	if ip.Is4() {
-		return ip.v4(0)&0xf0 == 0xe0
-	}
-	// IP Version 6 Addressing Architecture (2.4 Address Type Identification)
-	// https://datatracker.ietf.org/doc/html/rfc4291#section-2.4
-	if ip.Is6() {
-		return ip.addr.hi>>(64-8) == 0xff // ip.v6(0) == 0xff
-	}
-	return false // zero value
-}
-
-// IsInterfaceLocalMulticast reports whether ip is an IPv6 interface-local
-// multicast address.
-func (ip Addr) IsInterfaceLocalMulticast() bool {
-	// IPv6 Addressing Architecture (2.7.1. Pre-Defined Multicast Addresses)
-	// https://datatracker.ietf.org/doc/html/rfc4291#section-2.7.1
-	if ip.Is6() {
-		return ip.v6u16(0)&0xff0f == 0xff01
-	}
-	return false // zero value
-}
-
-// IsLinkLocalMulticast reports whether ip is a link-local multicast address.
-func (ip Addr) IsLinkLocalMulticast() bool {
-	// IPv4 Multicast Guidelines (4. Local Network Control Block (224.0.0/24))
-	// https://datatracker.ietf.org/doc/html/rfc5771#section-4
-	if ip.Is4() {
-		return ip.v4(0) == 224 && ip.v4(1) == 0 && ip.v4(2) == 0
-	}
-	// IPv6 Addressing Architecture (2.7.1. Pre-Defined Multicast Addresses)
-	// https://datatracker.ietf.org/doc/html/rfc4291#section-2.7.1
-	if ip.Is6() {
-		return ip.v6u16(0)&0xff0f == 0xff02
-	}
-	return false // zero value
-}
-
-// IsGlobalUnicast reports whether ip is a global unicast address.
-//
-// It returns true for IPv6 addresses which fall outside of the current
-// IANA-allocated 2000::/3 global unicast space, with the exception of the
-// link-local address space. It also returns true even if ip is in the IPv4
-// private address space or IPv6 unique local address space.
-// It returns false for the zero Addr.
-//
-// For reference, see RFC 1122, RFC 4291, and RFC 4632.
-func (ip Addr) IsGlobalUnicast() bool {
-	if ip.z == z0 {
-		// Invalid or zero-value.
-		return false
-	}
-
-	// Match package net's IsGlobalUnicast logic. Notably private IPv4 addresses
-	// and ULA IPv6 addresses are still considered "global unicast".
-	if ip.Is4() && (ip == IPv4Unspecified() || ip == AddrFrom4([4]byte{255, 255, 255, 255})) {
-		return false
-	}
-
-	return ip != IPv6Unspecified() &&
-		!ip.IsLoopback() &&
-		!ip.IsMulticast() &&
-		!ip.IsLinkLocalUnicast()
-}
-
-// IsPrivate reports whether ip is a private address, according to RFC 1918
-// (IPv4 addresses) and RFC 4193 (IPv6 addresses). That is, it reports whether
-// ip is in 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16, or fc00::/7. This is the
-// same as net.IP.IsPrivate.
-func (ip Addr) IsPrivate() bool {
-	// Match the stdlib's IsPrivate logic.
-	if ip.Is4() {
-		// RFC 1918 allocates 10.0.0.0/8, 172.16.0.0/12, and 192.168.0.0/16 as
-		// private IPv4 address subnets.
-		return ip.v4(0) == 10 ||
-			(ip.v4(0) == 172 && ip.v4(1)&0xf0 == 16) ||
-			(ip.v4(0) == 192 && ip.v4(1) == 168)
-	}
-
-	if ip.Is6() {
-		// RFC 4193 allocates fc00::/7 as the unique local unicast IPv6 address
-		// subnet.
-		return ip.v6(0)&0xfe == 0xfc
-	}
-
-	return false // zero value
-}
-
-// IsUnspecified reports whether ip is an unspecified address, either the IPv4
-// address "0.0.0.0" or the IPv6 address "::".
-//
-// Note that the zero Addr is not an unspecified address.
-func (ip Addr) IsUnspecified() bool {
-	return ip == IPv4Unspecified() || ip == IPv6Unspecified()
-}
-
-// Prefix keeps only the top b bits of IP, producing a Prefix
-// of the specified length.
-// If ip is a zero Addr, Prefix always returns a zero Prefix and a nil error.
-// Otherwise, if bits is less than zero or greater than ip.BitLen(),
-// Prefix returns an error.
-func (ip Addr) Prefix(b int) (Prefix, error) {
-	if b < 0 {
-		return Prefix{}, errors.New("negative Prefix bits")
-	}
-	effectiveBits := b
-	switch ip.z {
-	case z0:
-		return Prefix{}, nil
-	case z4:
-		if b > 32 {
-			return Prefix{}, errors.New("prefix length " + itoa.Itoa(b) + " too large for IPv4")
-		}
-		effectiveBits += 96
-	default:
-		if b > 128 {
-			return Prefix{}, errors.New("prefix length " + itoa.Itoa(b) + " too large for IPv6")
-		}
-	}
-	ip.addr = ip.addr.and(mask6(effectiveBits))
-	return PrefixFrom(ip, b), nil
-}
-
-const (
-	netIPv4len = 4
-	netIPv6len = 16
-)
-
-// As16 returns the IP address in its 16-byte representation.
-// IPv4 addresses are returned in their v6-mapped form.
-// IPv6 addresses with zones are returned without their zone (use the
-// Zone method to get it).
-// The ip zero value returns all zeroes.
-func (ip Addr) As16() (a16 [16]byte) {
-	bePutUint64(a16[:8], ip.addr.hi)
-	bePutUint64(a16[8:], ip.addr.lo)
-	return a16
-}
-
-// As4 returns an IPv4 or IPv4-in-IPv6 address in its 4-byte representation.
-// If ip is the zero Addr or an IPv6 address, As4 panics.
-// Note that 0.0.0.0 is not the zero Addr.
-func (ip Addr) As4() (a4 [4]byte) {
-	if ip.z == z4 || ip.Is4In6() {
-		bePutUint32(a4[:], uint32(ip.addr.lo))
-		return a4
-	}
-	if ip.z == z0 {
-		panic("As4 called on IP zero value")
-	}
-	panic("As4 called on IPv6 address")
-}
-
-// AsSlice returns an IPv4 or IPv6 address in its respective 4-byte or 16-byte representation.
-func (ip Addr) AsSlice() []byte {
-	switch ip.z {
-	case z0:
-		return nil
-	case z4:
-		var ret [4]byte
-		bePutUint32(ret[:], uint32(ip.addr.lo))
-		return ret[:]
-	default:
-		var ret [16]byte
-		bePutUint64(ret[:8], ip.addr.hi)
-		bePutUint64(ret[8:], ip.addr.lo)
-		return ret[:]
-	}
-}
-
-// Next returns the address following ip.
-// If there is none, it returns the zero Addr.
-func (ip Addr) Next() Addr {
-	ip.addr = ip.addr.addOne()
-	if ip.Is4() {
-		if uint32(ip.addr.lo) == 0 {
-			// Overflowed.
-			return Addr{}
-		}
-	} else {
-		if ip.addr.isZero() {
-			// Overflowed
-			return Addr{}
-		}
-	}
-	return ip
-}
-
-// Prev returns the IP before ip.
-// If there is none, it returns the IP zero value.
-func (ip Addr) Prev() Addr {
-	if ip.Is4() {
-		if uint32(ip.addr.lo) == 0 {
-			return Addr{}
-		}
-	} else if ip.addr.isZero() {
-		return Addr{}
-	}
-	ip.addr = ip.addr.subOne()
-	return ip
-}
-
-// String returns the string form of the IP address ip.
-// It returns one of 5 forms:
-//
-//   - "invalid IP", if ip is the zero Addr
-//   - IPv4 dotted decimal ("192.0.2.1")
-//   - IPv6 ("2001:db8::1")
-//   - "::ffff:1.2.3.4" (if Is4In6)
-//   - IPv6 with zone ("fe80:db8::1%eth0")
-//
-// Note that unlike package net's IP.String method,
-// IP4-mapped IPv6 addresses format with a "::ffff:"
-// prefix before the dotted quad.
-func (ip Addr) String() string {
-	switch ip.z {
-	case z0:
-		return "invalid IP"
-	case z4:
-		return ip.string4()
-	default:
-		if ip.Is4In6() {
-			// TODO(bradfitz): this could alloc less.
-			if z := ip.Zone(); z != "" {
-				return "::ffff:" + ip.Unmap().String() + "%" + z
-			} else {
-				return "::ffff:" + ip.Unmap().String()
-			}
-		}
-		return ip.string6()
-	}
-}
-
-// AppendTo appends a text encoding of ip,
-// as generated by MarshalText,
-// to b and returns the extended buffer.
-func (ip Addr) AppendTo(b []byte) []byte {
-	switch ip.z {
-	case z0:
-		return b
-	case z4:
-		return ip.appendTo4(b)
-	default:
-		if ip.Is4In6() {
-			b = append(b, "::ffff:"...)
-			b = ip.Unmap().appendTo4(b)
-			if z := ip.Zone(); z != "" {
-				b = append(b, '%')
-				b = append(b, z...)
-			}
-			return b
-		}
-		return ip.appendTo6(b)
-	}
-}
-
-// digits is a string of the hex digits from 0 to f. It's used in
-// appendDecimal and appendHex to format IP addresses.
-const digits = "0123456789abcdef"
-
-// appendDecimal appends the decimal string representation of x to b.
-func appendDecimal(b []byte, x uint8) []byte {
-	// Using this function rather than strconv.AppendUint makes IPv4
-	// string building 2x faster.
-
-	if x >= 100 {
-		b = append(b, digits[x/100])
-	}
-	if x >= 10 {
-		b = append(b, digits[x/10%10])
-	}
-	return append(b, digits[x%10])
-}
-
-// appendHex appends the hex string representation of x to b.
-func appendHex(b []byte, x uint16) []byte {
-	// Using this function rather than strconv.AppendUint makes IPv6
-	// string building 2x faster.
-
-	if x >= 0x1000 {
-		b = append(b, digits[x>>12])
-	}
-	if x >= 0x100 {
-		b = append(b, digits[x>>8&0xf])
-	}
-	if x >= 0x10 {
-		b = append(b, digits[x>>4&0xf])
-	}
-	return append(b, digits[x&0xf])
-}
-
-// appendHexPad appends the fully padded hex string representation of x to b.
-func appendHexPad(b []byte, x uint16) []byte {
-	return append(b, digits[x>>12], digits[x>>8&0xf], digits[x>>4&0xf], digits[x&0xf])
-}
-
-func (ip Addr) string4() string {
-	const max = len("255.255.255.255")
-	ret := make([]byte, 0, max)
-	ret = ip.appendTo4(ret)
-	return string(ret)
-}
-
-func (ip Addr) appendTo4(ret []byte) []byte {
-	ret = appendDecimal(ret, ip.v4(0))
-	ret = append(ret, '.')
-	ret = appendDecimal(ret, ip.v4(1))
-	ret = append(ret, '.')
-	ret = appendDecimal(ret, ip.v4(2))
-	ret = append(ret, '.')
-	ret = appendDecimal(ret, ip.v4(3))
-	return ret
-}
-
-// string6 formats ip in IPv6 textual representation. It follows the
-// guidelines in section 4 of RFC 5952
-// (https://tools.ietf.org/html/rfc5952#section-4): no unnecessary
-// zeros, use :: to elide the longest run of zeros, and don't use ::
-// to compact a single zero field.
-func (ip Addr) string6() string {
-	// Use a zone with a "plausibly long" name, so that most zone-ful
-	// IP addresses won't require additional allocation.
-	//
-	// The compiler does a cool optimization here, where ret ends up
-	// stack-allocated and so the only allocation this function does
-	// is to construct the returned string. As such, it's okay to be a
-	// bit greedy here, size-wise.
-	const max = len("ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff%enp5s0")
-	ret := make([]byte, 0, max)
-	ret = ip.appendTo6(ret)
-	return string(ret)
-}
-
-func (ip Addr) appendTo6(ret []byte) []byte {
-	zeroStart, zeroEnd := uint8(255), uint8(255)
-	for i := uint8(0); i < 8; i++ {
-		j := i
-		for j < 8 && ip.v6u16(j) == 0 {
-			j++
-		}
-		if l := j - i; l >= 2 && l > zeroEnd-zeroStart {
-			zeroStart, zeroEnd = i, j
-		}
-	}
-
-	for i := uint8(0); i < 8; i++ {
-		if i == zeroStart {
-			ret = append(ret, ':', ':')
-			i = zeroEnd
-			if i >= 8 {
-				break
-			}
-		} else if i > 0 {
-			ret = append(ret, ':')
-		}
-
-		ret = appendHex(ret, ip.v6u16(i))
-	}
-
-	if ip.z != z6noz {
-		ret = append(ret, '%')
-		ret = append(ret, ip.Zone()...)
-	}
-	return ret
-}
-
-// StringExpanded is like String but IPv6 addresses are expanded with leading
-// zeroes and no "::" compression. For example, "2001:db8::1" becomes
-// "2001:0db8:0000:0000:0000:0000:0000:0001".
-func (ip Addr) StringExpanded() string {
-	switch ip.z {
-	case z0, z4:
-		return ip.String()
-	}
-
-	const size = len("ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff")
-	ret := make([]byte, 0, size)
-	for i := uint8(0); i < 8; i++ {
-		if i > 0 {
-			ret = append(ret, ':')
-		}
-
-		ret = appendHexPad(ret, ip.v6u16(i))
-	}
-
-	if ip.z != z6noz {
-		// The addition of a zone will cause a second allocation, but when there
-		// is no zone the ret slice will be stack allocated.
-		ret = append(ret, '%')
-		ret = append(ret, ip.Zone()...)
-	}
-	return string(ret)
-}
-
-// MarshalText implements the encoding.TextMarshaler interface,
-// The encoding is the same as returned by String, with one exception:
-// If ip is the zero Addr, the encoding is the empty string.
-func (ip Addr) MarshalText() ([]byte, error) {
-	switch ip.z {
-	case z0:
-		return []byte(""), nil
-	case z4:
-		max := len("255.255.255.255")
-		b := make([]byte, 0, max)
-		return ip.appendTo4(b), nil
-	default:
-		max := len("ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff%enp5s0")
-		b := make([]byte, 0, max)
-		if ip.Is4In6() {
-			b = append(b, "::ffff:"...)
-			b = ip.Unmap().appendTo4(b)
-			if z := ip.Zone(); z != "" {
-				b = append(b, '%')
-				b = append(b, z...)
-			}
-			return b, nil
-		}
-		return ip.appendTo6(b), nil
-	}
-
-}
-
-// UnmarshalText implements the encoding.TextUnmarshaler interface.
-// The IP address is expected in a form accepted by ParseAddr.
-//
-// If text is empty, UnmarshalText sets *ip to the zero Addr and
-// returns no error.
-func (ip *Addr) UnmarshalText(text []byte) error {
-	if len(text) == 0 {
-		*ip = Addr{}
-		return nil
-	}
-	var err error
-	*ip, err = ParseAddr(string(text))
-	return err
-}
-
-func (ip Addr) marshalBinaryWithTrailingBytes(trailingBytes int) []byte {
-	var b []byte
-	switch ip.z {
-	case z0:
-		b = make([]byte, trailingBytes)
-	case z4:
-		b = make([]byte, 4+trailingBytes)
-		bePutUint32(b, uint32(ip.addr.lo))
-	default:
-		z := ip.Zone()
-		b = make([]byte, 16+len(z)+trailingBytes)
-		bePutUint64(b[:8], ip.addr.hi)
-		bePutUint64(b[8:], ip.addr.lo)
-		copy(b[16:], z)
-	}
-	return b
-}
-
-// MarshalBinary implements the encoding.BinaryMarshaler interface.
-// It returns a zero-length slice for the zero Addr,
-// the 4-byte form for an IPv4 address,
-// and the 16-byte form with zone appended for an IPv6 address.
-func (ip Addr) MarshalBinary() ([]byte, error) {
-	return ip.marshalBinaryWithTrailingBytes(0), nil
-}
-
-// UnmarshalBinary implements the encoding.BinaryUnmarshaler interface.
-// It expects data in the form generated by MarshalBinary.
-func (ip *Addr) UnmarshalBinary(b []byte) error {
-	n := len(b)
-	switch {
-	case n == 0:
-		*ip = Addr{}
-		return nil
-	case n == 4:
-		*ip = AddrFrom4(*(*[4]byte)(b))
-		return nil
-	case n == 16:
-		*ip = ipv6Slice(b)
-		return nil
-	case n > 16:
-		*ip = ipv6Slice(b[:16]).WithZone(string(b[16:]))
-		return nil
-	}
-	return errors.New("unexpected slice size")
-}
-
-// AddrPort is an IP and a port number.
-type AddrPort struct {
-	ip   Addr
-	port uint16
-}
-
-// AddrPortFrom returns an AddrPort with the provided IP and port.
-// It does not allocate.
-func AddrPortFrom(ip Addr, port uint16) AddrPort { return AddrPort{ip: ip, port: port} }
-
-// Addr returns p's IP address.
-func (p AddrPort) Addr() Addr { return p.ip }
-
-// Port returns p's port.
-func (p AddrPort) Port() uint16 { return p.port }
-
-// splitAddrPort splits s into an IP address string and a port
-// string. It splits strings shaped like "foo:bar" or "[foo]:bar",
-// without further validating the substrings. v6 indicates whether the
-// ip string should parse as an IPv6 address or an IPv4 address, in
-// order for s to be a valid ip:port string.
-func splitAddrPort(s string) (ip, port string, v6 bool, err error) {
-	i := stringsLastIndexByte(s, ':')
-	if i == -1 {
-		return "", "", false, errors.New("not an ip:port")
-	}
-
-	ip, port = s[:i], s[i+1:]
-	if len(ip) == 0 {
-		return "", "", false, errors.New("no IP")
-	}
-	if len(port) == 0 {
-		return "", "", false, errors.New("no port")
-	}
-	if ip[0] == '[' {
-		if len(ip) < 2 || ip[len(ip)-1] != ']' {
-			return "", "", false, errors.New("missing ]")
-		}
-		ip = ip[1 : len(ip)-1]
-		v6 = true
-	}
-
-	return ip, port, v6, nil
-}
-
-// ParseAddrPort parses s as an AddrPort.
-//
-// It doesn't do any name resolution: both the address and the port
-// must be numeric.
-func ParseAddrPort(s string) (AddrPort, error) {
-	var ipp AddrPort
-	ip, port, v6, err := splitAddrPort(s)
-	if err != nil {
-		return ipp, err
-	}
-	port16, err := strconv.ParseUint(port, 10, 16)
-	if err != nil {
-		return ipp, errors.New("invalid port " + strconv.Quote(port) + " parsing " + strconv.Quote(s))
-	}
-	ipp.port = uint16(port16)
-	ipp.ip, err = ParseAddr(ip)
-	if err != nil {
-		return AddrPort{}, err
-	}
-	if v6 && ipp.ip.Is4() {
-		return AddrPort{}, errors.New("invalid ip:port " + strconv.Quote(s) + ", square brackets can only be used with IPv6 addresses")
-	} else if !v6 && ipp.ip.Is6() {
-		return AddrPort{}, errors.New("invalid ip:port " + strconv.Quote(s) + ", IPv6 addresses must be surrounded by square brackets")
-	}
-	return ipp, nil
-}
-
-// MustParseAddrPort calls ParseAddrPort(s) and panics on error.
-// It is intended for use in tests with hard-coded strings.
-func MustParseAddrPort(s string) AddrPort {
-	ip, err := ParseAddrPort(s)
-	if err != nil {
-		panic(err)
-	}
-	return ip
-}
-
-// isZero reports whether p is the zero AddrPort.
-func (p AddrPort) isZero() bool { return p == AddrPort{} }
-
-// IsValid reports whether p.IP() is valid.
-// All ports are valid, including zero.
-func (p AddrPort) IsValid() bool { return p.ip.IsValid() }
-
-func (p AddrPort) String() string {
-	switch p.ip.z {
-	case z0:
-		return "invalid AddrPort"
-	case z4:
-		a := p.ip.As4()
-		buf := make([]byte, 0, 21)
-		for i := range a {
-			buf = strconv.AppendUint(buf, uint64(a[i]), 10)
-			buf = append(buf, "...:"[i])
-		}
-		buf = strconv.AppendUint(buf, uint64(p.port), 10)
-		return string(buf)
-	default:
-		// TODO: this could be more efficient allocation-wise:
-		return joinHostPort(p.ip.String(), itoa.Itoa(int(p.port)))
-	}
-}
-
-func joinHostPort(host, port string) string {
-	// We assume that host is a literal IPv6 address if host has
-	// colons.
-	if bytealg.IndexByteString(host, ':') >= 0 {
-		return "[" + host + "]:" + port
-	}
-	return host + ":" + port
-}
-
-// AppendTo appends a text encoding of p,
-// as generated by MarshalText,
-// to b and returns the extended buffer.
-func (p AddrPort) AppendTo(b []byte) []byte {
-	switch p.ip.z {
-	case z0:
-		return b
-	case z4:
-		b = p.ip.appendTo4(b)
-	default:
-		if p.ip.Is4In6() {
-			b = append(b, "[::ffff:"...)
-			b = p.ip.Unmap().appendTo4(b)
-			if z := p.ip.Zone(); z != "" {
-				b = append(b, '%')
-				b = append(b, z...)
-			}
-		} else {
-			b = append(b, '[')
-			b = p.ip.appendTo6(b)
-		}
-		b = append(b, ']')
-	}
-	b = append(b, ':')
-	b = strconv.AppendInt(b, int64(p.port), 10)
-	return b
-}
-
-// MarshalText implements the encoding.TextMarshaler interface. The
-// encoding is the same as returned by String, with one exception: if
-// p.Addr() is the zero Addr, the encoding is the empty string.
-func (p AddrPort) MarshalText() ([]byte, error) {
-	var max int
-	switch p.ip.z {
-	case z0:
-	case z4:
-		max = len("255.255.255.255:65535")
-	default:
-		max = len("[ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff%enp5s0]:65535")
-	}
-	b := make([]byte, 0, max)
-	b = p.AppendTo(b)
-	return b, nil
-}
-
-// UnmarshalText implements the encoding.TextUnmarshaler
-// interface. The AddrPort is expected in a form
-// generated by MarshalText or accepted by ParseAddrPort.
-func (p *AddrPort) UnmarshalText(text []byte) error {
-	if len(text) == 0 {
-		*p = AddrPort{}
-		return nil
-	}
-	var err error
-	*p, err = ParseAddrPort(string(text))
-	return err
-}
-
-// MarshalBinary implements the encoding.BinaryMarshaler interface.
-// It returns Addr.MarshalBinary with an additional two bytes appended
-// containing the port in little-endian.
-func (p AddrPort) MarshalBinary() ([]byte, error) {
-	b := p.Addr().marshalBinaryWithTrailingBytes(2)
-	lePutUint16(b[len(b)-2:], p.Port())
-	return b, nil
-}
-
-// UnmarshalBinary implements the encoding.BinaryUnmarshaler interface.
-// It expects data in the form generated by MarshalBinary.
-func (p *AddrPort) UnmarshalBinary(b []byte) error {
-	if len(b) < 2 {
-		return errors.New("unexpected slice size")
-	}
-	var addr Addr
-	err := addr.UnmarshalBinary(b[:len(b)-2])
-	if err != nil {
-		return err
-	}
-	*p = AddrPortFrom(addr, leUint16(b[len(b)-2:]))
-	return nil
-}
-
-// Prefix is an IP address prefix (CIDR) representing an IP network.
-//
-// The first Bits() of Addr() are specified. The remaining bits match any address.
-// The range of Bits() is [0,32] for IPv4 or [0,128] for IPv6.
-type Prefix struct {
-	ip Addr
-
-	// bits is logically a uint8 (storing [0,128]) but also
-	// encodes an "invalid" bit, currently represented by the
-	// invalidPrefixBits sentinel value. It could be packed into
-	// the uint8 more with more complicated expressions in the
-	// accessors, but the extra byte (in padding anyway) doesn't
-	// hurt and simplifies code below.
-	bits int16
-}
-
-// invalidPrefixBits is the Prefix.bits value used when PrefixFrom is
-// outside the range of a uint8. It's returned as the int -1 in the
-// public API.
-const invalidPrefixBits = -1
-
-// PrefixFrom returns a Prefix with the provided IP address and bit
-// prefix length.
-//
-// It does not allocate. Unlike Addr.Prefix, PrefixFrom does not mask
-// off the host bits of ip.
-//
-// If bits is less than zero or greater than ip.BitLen, Prefix.Bits
-// will return an invalid value -1.
-func PrefixFrom(ip Addr, bits int) Prefix {
-	if bits < 0 || bits > ip.BitLen() {
-		bits = invalidPrefixBits
-	}
-	b16 := int16(bits)
-	return Prefix{
-		ip:   ip.withoutZone(),
-		bits: b16,
-	}
-}
-
-// Addr returns p's IP address.
-func (p Prefix) Addr() Addr { return p.ip }
-
-// Bits returns p's prefix length.
-//
-// It reports -1 if invalid.
-func (p Prefix) Bits() int { return int(p.bits) }
-
-// IsValid reports whether p.Bits() has a valid range for p.IP().
-// If p.Addr() is the zero Addr, IsValid returns false.
-// Note that if p is the zero Prefix, then p.IsValid() == false.
-func (p Prefix) IsValid() bool { return !p.ip.isZero() && p.bits >= 0 && int(p.bits) <= p.ip.BitLen() }
-
-func (p Prefix) isZero() bool { return p == Prefix{} }
-
-// IsSingleIP reports whether p contains exactly one IP.
-func (p Prefix) IsSingleIP() bool { return p.bits != 0 && int(p.bits) == p.ip.BitLen() }
-
-// ParsePrefix parses s as an IP address prefix.
-// The string can be in the form "192.168.1.0/24" or "2001:db8::/32",
-// the CIDR notation defined in RFC 4632 and RFC 4291.
-//
-// Note that masked address bits are not zeroed. Use Masked for that.
-func ParsePrefix(s string) (Prefix, error) {
-	i := stringsLastIndexByte(s, '/')
-	if i < 0 {
-		return Prefix{}, errors.New("netip.ParsePrefix(" + strconv.Quote(s) + "): no '/'")
-	}
-	ip, err := ParseAddr(s[:i])
-	if err != nil {
-		return Prefix{}, errors.New("netip.ParsePrefix(" + strconv.Quote(s) + "): " + err.Error())
-	}
-	bitsStr := s[i+1:]
-	bits, err := strconv.Atoi(bitsStr)
-	if err != nil {
-		return Prefix{}, errors.New("netip.ParsePrefix(" + strconv.Quote(s) + ": bad bits after slash: " + strconv.Quote(bitsStr))
-	}
-	maxBits := 32
-	if ip.Is6() {
-		maxBits = 128
-	}
-	if bits < 0 || bits > maxBits {
-		return Prefix{}, errors.New("netip.ParsePrefix(" + strconv.Quote(s) + ": prefix length out of range")
-	}
-	return PrefixFrom(ip, bits), nil
-}
-
-// MustParsePrefix calls ParsePrefix(s) and panics on error.
-// It is intended for use in tests with hard-coded strings.
-func MustParsePrefix(s string) Prefix {
-	ip, err := ParsePrefix(s)
-	if err != nil {
-		panic(err)
-	}
-	return ip
-}
-
-// Masked returns p in its canonical form, with all but the high
-// p.Bits() bits of p.Addr() masked off.
-//
-// If p is zero or otherwise invalid, Masked returns the zero Prefix.
-func (p Prefix) Masked() Prefix {
-	if m, err := p.ip.Prefix(int(p.bits)); err == nil {
-		return m
-	}
-	return Prefix{}
-}
-
-// Contains reports whether the network p includes ip.
-//
-// An IPv4 address will not match an IPv6 prefix.
-// A v6-mapped IPv6 address will not match an IPv4 prefix.
-// A zero-value IP will not match any prefix.
-// If ip has an IPv6 zone, Contains returns false,
-// because Prefixes strip zones.
-func (p Prefix) Contains(ip Addr) bool {
-	if !p.IsValid() || ip.hasZone() {
-		return false
-	}
-	if f1, f2 := p.ip.BitLen(), ip.BitLen(); f1 == 0 || f2 == 0 || f1 != f2 {
-		return false
-	}
-	if ip.Is4() {
-		// xor the IP addresses together; mismatched bits are now ones.
-		// Shift away the number of bits we don't care about.
-		// Shifts in Go are more efficient if the compiler can prove
-		// that the shift amount is smaller than the width of the shifted type (64 here).
-		// We know that p.bits is in the range 0..32 because p is Valid;
-		// the compiler doesn't know that, so mask with 63 to help it.
-		// Now truncate to 32 bits, because this is IPv4.
-		// If all the bits we care about are equal, the result will be zero.
-		return uint32((ip.addr.lo^p.ip.addr.lo)>>((32-p.bits)&63)) == 0
-	} else {
-		// xor the IP addresses together.
-		// Mask away the bits we don't care about.
-		// If all the bits we care about are equal, the result will be zero.
-		return ip.addr.xor(p.ip.addr).and(mask6(int(p.bits))).isZero()
-	}
-}
-
-// Overlaps reports whether p and o contain any IP addresses in common.
-//
-// If p and o are of different address families or either have a zero
-// IP, it reports false. Like the Contains method, a prefix with a
-// v6-mapped IPv4 IP is still treated as an IPv6 mask.
-func (p Prefix) Overlaps(o Prefix) bool {
-	if !p.IsValid() || !o.IsValid() {
-		return false
-	}
-	if p == o {
-		return true
-	}
-	if p.ip.Is4() != o.ip.Is4() {
-		return false
-	}
-	var minBits int16
-	if p.bits < o.bits {
-		minBits = p.bits
-	} else {
-		minBits = o.bits
-	}
-	if minBits == 0 {
-		return true
-	}
-	// One of these Prefix calls might look redundant, but we don't require
-	// that p and o values are normalized (via Prefix.Masked) first,
-	// so the Prefix call on the one that's already minBits serves to zero
-	// out any remaining bits in IP.
-	var err error
-	if p, err = p.ip.Prefix(int(minBits)); err != nil {
-		return false
-	}
-	if o, err = o.ip.Prefix(int(minBits)); err != nil {
-		return false
-	}
-	return p.ip == o.ip
-}
-
-// AppendTo appends a text encoding of p,
-// as generated by MarshalText,
-// to b and returns the extended buffer.
-func (p Prefix) AppendTo(b []byte) []byte {
-	if p.isZero() {
-		return b
-	}
-	if !p.IsValid() {
-		return append(b, "invalid Prefix"...)
-	}
-
-	// p.ip is non-nil, because p is valid.
-	if p.ip.z == z4 {
-		b = p.ip.appendTo4(b)
-	} else {
-		if p.ip.Is4In6() {
-			b = append(b, "::ffff:"...)
-			b = p.ip.Unmap().appendTo4(b)
-		} else {
-			b = p.ip.appendTo6(b)
-		}
-	}
-
-	b = append(b, '/')
-	b = appendDecimal(b, uint8(p.bits))
-	return b
-}
-
-// MarshalText implements the encoding.TextMarshaler interface,
-// The encoding is the same as returned by String, with one exception:
-// If p is the zero value, the encoding is the empty string.
-func (p Prefix) MarshalText() ([]byte, error) {
-	var max int
-	switch p.ip.z {
-	case z0:
-	case z4:
-		max = len("255.255.255.255/32")
-	default:
-		max = len("ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff%enp5s0/128")
-	}
-	b := make([]byte, 0, max)
-	b = p.AppendTo(b)
-	return b, nil
-}
-
-// UnmarshalText implements the encoding.TextUnmarshaler interface.
-// The IP address is expected in a form accepted by ParsePrefix
-// or generated by MarshalText.
-func (p *Prefix) UnmarshalText(text []byte) error {
-	if len(text) == 0 {
-		*p = Prefix{}
-		return nil
-	}
-	var err error
-	*p, err = ParsePrefix(string(text))
-	return err
-}
-
-// MarshalBinary implements the encoding.BinaryMarshaler interface.
-// It returns Addr.MarshalBinary with an additional byte appended
-// containing the prefix bits.
-func (p Prefix) MarshalBinary() ([]byte, error) {
-	b := p.Addr().withoutZone().marshalBinaryWithTrailingBytes(1)
-	b[len(b)-1] = uint8(p.Bits())
-	return b, nil
-}
-
-// UnmarshalBinary implements the encoding.BinaryUnmarshaler interface.
-// It expects data in the form generated by MarshalBinary.
-func (p *Prefix) UnmarshalBinary(b []byte) error {
-	if len(b) < 1 {
-		return errors.New("unexpected slice size")
-	}
-	var addr Addr
-	err := addr.UnmarshalBinary(b[:len(b)-1])
-	if err != nil {
-		return err
-	}
-	*p = PrefixFrom(addr, int(b[len(b)-1]))
-	return nil
-}
-
-// String returns the CIDR notation of p: "<ip>/<bits>".
-func (p Prefix) String() string {
-	if !p.IsValid() {
-		return "invalid Prefix"
-	}
-	return p.ip.String() + "/" + itoa.Itoa(int(p.bits))
-}
diff --git a/contrib/go/_std_1.18/src/net/nss.go b/contrib/go/_std_1.18/src/net/nss.go
deleted file mode 100644
index ee5568883f..0000000000
--- a/contrib/go/_std_1.18/src/net/nss.go
+++ /dev/null
@@ -1,160 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
-
-package net
-
-import (
-	"errors"
-	"internal/bytealg"
-	"io"
-	"os"
-)
-
-// nssConf represents the state of the machine's /etc/nsswitch.conf file.
-type nssConf struct {
-	err     error                  // any error encountered opening or parsing the file
-	sources map[string][]nssSource // keyed by database (e.g. "hosts")
-}
-
-type nssSource struct {
-	source   string // e.g. "compat", "files", "mdns4_minimal"
-	criteria []nssCriterion
-}
-
-// standardCriteria reports all specified criteria have the default
-// status actions.
-func (s nssSource) standardCriteria() bool {
-	for i, crit := range s.criteria {
-		if !crit.standardStatusAction(i == len(s.criteria)-1) {
-			return false
-		}
-	}
-	return true
-}
-
-// nssCriterion is the parsed structure of one of the criteria in brackets
-// after an NSS source name.
-type nssCriterion struct {
-	negate bool   // if "!" was present
-	status string // e.g. "success", "unavail" (lowercase)
-	action string // e.g. "return", "continue" (lowercase)
-}
-
-// standardStatusAction reports whether c is equivalent to not
-// specifying the criterion at all. last is whether this criteria is the
-// last in the list.
-func (c nssCriterion) standardStatusAction(last bool) bool {
-	if c.negate {
-		return false
-	}
-	var def string
-	switch c.status {
-	case "success":
-		def = "return"
-	case "notfound", "unavail", "tryagain":
-		def = "continue"
-	default:
-		// Unknown status
-		return false
-	}
-	if last && c.action == "return" {
-		return true
-	}
-	return c.action == def
-}
-
-func parseNSSConfFile(file string) *nssConf {
-	f, err := os.Open(file)
-	if err != nil {
-		return &nssConf{err: err}
-	}
-	defer f.Close()
-	return parseNSSConf(f)
-}
-
-func parseNSSConf(r io.Reader) *nssConf {
-	slurp, err := readFull(r)
-	if err != nil {
-		return &nssConf{err: err}
-	}
-	conf := new(nssConf)
-	conf.err = foreachLine(slurp, func(line []byte) error {
-		line = trimSpace(removeComment(line))
-		if len(line) == 0 {
-			return nil
-		}
-		colon := bytealg.IndexByte(line, ':')
-		if colon == -1 {
-			return errors.New("no colon on line")
-		}
-		db := string(trimSpace(line[:colon]))
-		srcs := line[colon+1:]
-		for {
-			srcs = trimSpace(srcs)
-			if len(srcs) == 0 {
-				break
-			}
-			sp := bytealg.IndexByte(srcs, ' ')
-			var src string
-			if sp == -1 {
-				src = string(srcs)
-				srcs = nil // done
-			} else {
-				src = string(srcs[:sp])
-				srcs = trimSpace(srcs[sp+1:])
-			}
-			var criteria []nssCriterion
-			// See if there's a criteria block in brackets.
-			if len(srcs) > 0 && srcs[0] == '[' {
-				bclose := bytealg.IndexByte(srcs, ']')
-				if bclose == -1 {
-					return errors.New("unclosed criterion bracket")
-				}
-				var err error
-				criteria, err = parseCriteria(srcs[1:bclose])
-				if err != nil {
-					return errors.New("invalid criteria: " + string(srcs[1:bclose]))
-				}
-				srcs = srcs[bclose+1:]
-			}
-			if conf.sources == nil {
-				conf.sources = make(map[string][]nssSource)
-			}
-			conf.sources[db] = append(conf.sources[db], nssSource{
-				source:   src,
-				criteria: criteria,
-			})
-		}
-		return nil
-	})
-	return conf
-}
-
-// parses "foo=bar !foo=bar"
-func parseCriteria(x []byte) (c []nssCriterion, err error) {
-	err = foreachField(x, func(f []byte) error {
-		not := false
-		if len(f) > 0 && f[0] == '!' {
-			not = true
-			f = f[1:]
-		}
-		if len(f) < 3 {
-			return errors.New("criterion too short")
-		}
-		eq := bytealg.IndexByte(f, '=')
-		if eq == -1 {
-			return errors.New("criterion lacks equal sign")
-		}
-		lowerASCIIBytes(f)
-		c = append(c, nssCriterion{
-			negate: not,
-			status: string(f[:eq]),
-			action: string(f[eq+1:]),
-		})
-		return nil
-	})
-	return
-}
diff --git a/contrib/go/_std_1.18/src/net/port_unix.go b/contrib/go/_std_1.18/src/net/port_unix.go
deleted file mode 100644
index 102722b2ca..0000000000
--- a/contrib/go/_std_1.18/src/net/port_unix.go
+++ /dev/null
@@ -1,57 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris
-
-// Read system port mappings from /etc/services
-
-package net
-
-import (
-	"internal/bytealg"
-	"sync"
-)
-
-var onceReadServices sync.Once
-
-func readServices() {
-	file, err := open("/etc/services")
-	if err != nil {
-		return
-	}
-	defer file.close()
-
-	for line, ok := file.readLine(); ok; line, ok = file.readLine() {
-		// "http 80/tcp www www-http # World Wide Web HTTP"
-		if i := bytealg.IndexByteString(line, '#'); i >= 0 {
-			line = line[:i]
-		}
-		f := getFields(line)
-		if len(f) < 2 {
-			continue
-		}
-		portnet := f[1] // "80/tcp"
-		port, j, ok := dtoi(portnet)
-		if !ok || port <= 0 || j >= len(portnet) || portnet[j] != '/' {
-			continue
-		}
-		netw := portnet[j+1:] // "tcp"
-		m, ok1 := services[netw]
-		if !ok1 {
-			m = make(map[string]int)
-			services[netw] = m
-		}
-		for i := 0; i < len(f); i++ {
-			if i != 1 { // f[1] was port/net
-				m[f[i]] = port
-			}
-		}
-	}
-}
-
-// goLookupPort is the native Go implementation of LookupPort.
-func goLookupPort(network, service string) (port int, err error) {
-	onceReadServices.Do(readServices)
-	return lookupPortMap(network, service)
-}
diff --git a/contrib/go/_std_1.18/src/net/sock_cloexec.go b/contrib/go/_std_1.18/src/net/sock_cloexec.go
deleted file mode 100644
index 56dab31b14..0000000000
--- a/contrib/go/_std_1.18/src/net/sock_cloexec.go
+++ /dev/null
@@ -1,50 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file implements sysSocket for platforms that provide a fast path for
-// setting SetNonblock and CloseOnExec.
-
-//go:build dragonfly || freebsd || illumos || linux || netbsd || openbsd
-
-package net
-
-import (
-	"internal/poll"
-	"os"
-	"syscall"
-)
-
-// Wrapper around the socket system call that marks the returned file
-// descriptor as nonblocking and close-on-exec.
-func sysSocket(family, sotype, proto int) (int, error) {
-	s, err := socketFunc(family, sotype|syscall.SOCK_NONBLOCK|syscall.SOCK_CLOEXEC, proto)
-	// On Linux the SOCK_NONBLOCK and SOCK_CLOEXEC flags were
-	// introduced in 2.6.27 kernel and on FreeBSD both flags were
-	// introduced in 10 kernel. If we get an EINVAL error on Linux
-	// or EPROTONOSUPPORT error on FreeBSD, fall back to using
-	// socket without them.
-	switch err {
-	case nil:
-		return s, nil
-	default:
-		return -1, os.NewSyscallError("socket", err)
-	case syscall.EPROTONOSUPPORT, syscall.EINVAL:
-	}
-
-	// See ../syscall/exec_unix.go for description of ForkLock.
-	syscall.ForkLock.RLock()
-	s, err = socketFunc(family, sotype, proto)
-	if err == nil {
-		syscall.CloseOnExec(s)
-	}
-	syscall.ForkLock.RUnlock()
-	if err != nil {
-		return -1, os.NewSyscallError("socket", err)
-	}
-	if err = syscall.SetNonblock(s, true); err != nil {
-		poll.CloseFunc(s)
-		return -1, os.NewSyscallError("setnonblock", err)
-	}
-	return s, nil
-}
diff --git a/contrib/go/_std_1.18/src/net/sock_linux.go b/contrib/go/_std_1.18/src/net/sock_linux.go
deleted file mode 100644
index 9f62ed3dee..0000000000
--- a/contrib/go/_std_1.18/src/net/sock_linux.go
+++ /dev/null
@@ -1,86 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package net
-
-import "syscall"
-
-func kernelVersion() (major int, minor int) {
-	var uname syscall.Utsname
-	if err := syscall.Uname(&uname); err != nil {
-		return
-	}
-
-	rl := uname.Release
-	var values [2]int
-	vi := 0
-	value := 0
-	for _, c := range rl {
-		if c >= '0' && c <= '9' {
-			value = (value * 10) + int(c-'0')
-		} else {
-			// Note that we're assuming N.N.N here.  If we see anything else we are likely to
-			// mis-parse it.
-			values[vi] = value
-			vi++
-			if vi >= len(values) {
-				break
-			}
-			value = 0
-		}
-	}
-	switch vi {
-	case 0:
-		return 0, 0
-	case 1:
-		return values[0], 0
-	case 2:
-		return values[0], values[1]
-	}
-	return
-}
-
-// Linux stores the backlog as:
-//
-//  - uint16 in kernel version < 4.1,
-//  - uint32 in kernel version >= 4.1
-//
-// Truncate number to avoid wrapping.
-//
-// See issue 5030 and 41470.
-func maxAckBacklog(n int) int {
-	major, minor := kernelVersion()
-	size := 16
-	if major > 4 || (major == 4 && minor >= 1) {
-		size = 32
-	}
-
-	var max uint = 1<<size - 1
-	if uint(n) > max {
-		n = int(max)
-	}
-	return n
-}
-
-func maxListenerBacklog() int {
-	fd, err := open("/proc/sys/net/core/somaxconn")
-	if err != nil {
-		return syscall.SOMAXCONN
-	}
-	defer fd.close()
-	l, ok := fd.readLine()
-	if !ok {
-		return syscall.SOMAXCONN
-	}
-	f := getFields(l)
-	n, _, ok := dtoi(f[0])
-	if n == 0 || !ok {
-		return syscall.SOMAXCONN
-	}
-
-	if n > 1<<16-1 {
-		return maxAckBacklog(n)
-	}
-	return n
-}
diff --git a/contrib/go/_std_1.18/src/net/sock_posix.go b/contrib/go/_std_1.18/src/net/sock_posix.go
deleted file mode 100644
index 98a48229c7..0000000000
--- a/contrib/go/_std_1.18/src/net/sock_posix.go
+++ /dev/null
@@ -1,254 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris || windows
-
-package net
-
-import (
-	"context"
-	"internal/poll"
-	"os"
-	"syscall"
-)
-
-// socket returns a network file descriptor that is ready for
-// asynchronous I/O using the network poller.
-func socket(ctx context.Context, net string, family, sotype, proto int, ipv6only bool, laddr, raddr sockaddr, ctrlFn func(string, string, syscall.RawConn) error) (fd *netFD, err error) {
-	s, err := sysSocket(family, sotype, proto)
-	if err != nil {
-		return nil, err
-	}
-	if err = setDefaultSockopts(s, family, sotype, ipv6only); err != nil {
-		poll.CloseFunc(s)
-		return nil, err
-	}
-	if fd, err = newFD(s, family, sotype, net); err != nil {
-		poll.CloseFunc(s)
-		return nil, err
-	}
-
-	// This function makes a network file descriptor for the
-	// following applications:
-	//
-	// - An endpoint holder that opens a passive stream
-	//   connection, known as a stream listener
-	//
-	// - An endpoint holder that opens a destination-unspecific
-	//   datagram connection, known as a datagram listener
-	//
-	// - An endpoint holder that opens an active stream or a
-	//   destination-specific datagram connection, known as a
-	//   dialer
-	//
-	// - An endpoint holder that opens the other connection, such
-	//   as talking to the protocol stack inside the kernel
-	//
-	// For stream and datagram listeners, they will only require
-	// named sockets, so we can assume that it's just a request
-	// from stream or datagram listeners when laddr is not nil but
-	// raddr is nil. Otherwise we assume it's just for dialers or
-	// the other connection holders.
-
-	if laddr != nil && raddr == nil {
-		switch sotype {
-		case syscall.SOCK_STREAM, syscall.SOCK_SEQPACKET:
-			if err := fd.listenStream(laddr, listenerBacklog(), ctrlFn); err != nil {
-				fd.Close()
-				return nil, err
-			}
-			return fd, nil
-		case syscall.SOCK_DGRAM:
-			if err := fd.listenDatagram(laddr, ctrlFn); err != nil {
-				fd.Close()
-				return nil, err
-			}
-			return fd, nil
-		}
-	}
-	if err := fd.dial(ctx, laddr, raddr, ctrlFn); err != nil {
-		fd.Close()
-		return nil, err
-	}
-	return fd, nil
-}
-
-func (fd *netFD) ctrlNetwork() string {
-	switch fd.net {
-	case "unix", "unixgram", "unixpacket":
-		return fd.net
-	}
-	switch fd.net[len(fd.net)-1] {
-	case '4', '6':
-		return fd.net
-	}
-	if fd.family == syscall.AF_INET {
-		return fd.net + "4"
-	}
-	return fd.net + "6"
-}
-
-func (fd *netFD) addrFunc() func(syscall.Sockaddr) Addr {
-	switch fd.family {
-	case syscall.AF_INET, syscall.AF_INET6:
-		switch fd.sotype {
-		case syscall.SOCK_STREAM:
-			return sockaddrToTCP
-		case syscall.SOCK_DGRAM:
-			return sockaddrToUDP
-		case syscall.SOCK_RAW:
-			return sockaddrToIP
-		}
-	case syscall.AF_UNIX:
-		switch fd.sotype {
-		case syscall.SOCK_STREAM:
-			return sockaddrToUnix
-		case syscall.SOCK_DGRAM:
-			return sockaddrToUnixgram
-		case syscall.SOCK_SEQPACKET:
-			return sockaddrToUnixpacket
-		}
-	}
-	return func(syscall.Sockaddr) Addr { return nil }
-}
-
-func (fd *netFD) dial(ctx context.Context, laddr, raddr sockaddr, ctrlFn func(string, string, syscall.RawConn) error) error {
-	if ctrlFn != nil {
-		c, err := newRawConn(fd)
-		if err != nil {
-			return err
-		}
-		var ctrlAddr string
-		if raddr != nil {
-			ctrlAddr = raddr.String()
-		} else if laddr != nil {
-			ctrlAddr = laddr.String()
-		}
-		if err := ctrlFn(fd.ctrlNetwork(), ctrlAddr, c); err != nil {
-			return err
-		}
-	}
-	var err error
-	var lsa syscall.Sockaddr
-	if laddr != nil {
-		if lsa, err = laddr.sockaddr(fd.family); err != nil {
-			return err
-		} else if lsa != nil {
-			if err = syscall.Bind(fd.pfd.Sysfd, lsa); err != nil {
-				return os.NewSyscallError("bind", err)
-			}
-		}
-	}
-	var rsa syscall.Sockaddr  // remote address from the user
-	var crsa syscall.Sockaddr // remote address we actually connected to
-	if raddr != nil {
-		if rsa, err = raddr.sockaddr(fd.family); err != nil {
-			return err
-		}
-		if crsa, err = fd.connect(ctx, lsa, rsa); err != nil {
-			return err
-		}
-		fd.isConnected = true
-	} else {
-		if err := fd.init(); err != nil {
-			return err
-		}
-	}
-	// Record the local and remote addresses from the actual socket.
-	// Get the local address by calling Getsockname.
-	// For the remote address, use
-	// 1) the one returned by the connect method, if any; or
-	// 2) the one from Getpeername, if it succeeds; or
-	// 3) the one passed to us as the raddr parameter.
-	lsa, _ = syscall.Getsockname(fd.pfd.Sysfd)
-	if crsa != nil {
-		fd.setAddr(fd.addrFunc()(lsa), fd.addrFunc()(crsa))
-	} else if rsa, _ = syscall.Getpeername(fd.pfd.Sysfd); rsa != nil {
-		fd.setAddr(fd.addrFunc()(lsa), fd.addrFunc()(rsa))
-	} else {
-		fd.setAddr(fd.addrFunc()(lsa), raddr)
-	}
-	return nil
-}
-
-func (fd *netFD) listenStream(laddr sockaddr, backlog int, ctrlFn func(string, string, syscall.RawConn) error) error {
-	var err error
-	if err = setDefaultListenerSockopts(fd.pfd.Sysfd); err != nil {
-		return err
-	}
-	var lsa syscall.Sockaddr
-	if lsa, err = laddr.sockaddr(fd.family); err != nil {
-		return err
-	}
-	if ctrlFn != nil {
-		c, err := newRawConn(fd)
-		if err != nil {
-			return err
-		}
-		if err := ctrlFn(fd.ctrlNetwork(), laddr.String(), c); err != nil {
-			return err
-		}
-	}
-	if err = syscall.Bind(fd.pfd.Sysfd, lsa); err != nil {
-		return os.NewSyscallError("bind", err)
-	}
-	if err = listenFunc(fd.pfd.Sysfd, backlog); err != nil {
-		return os.NewSyscallError("listen", err)
-	}
-	if err = fd.init(); err != nil {
-		return err
-	}
-	lsa, _ = syscall.Getsockname(fd.pfd.Sysfd)
-	fd.setAddr(fd.addrFunc()(lsa), nil)
-	return nil
-}
-
-func (fd *netFD) listenDatagram(laddr sockaddr, ctrlFn func(string, string, syscall.RawConn) error) error {
-	switch addr := laddr.(type) {
-	case *UDPAddr:
-		// We provide a socket that listens to a wildcard
-		// address with reusable UDP port when the given laddr
-		// is an appropriate UDP multicast address prefix.
-		// This makes it possible for a single UDP listener to
-		// join multiple different group addresses, for
-		// multiple UDP listeners that listen on the same UDP
-		// port to join the same group address.
-		if addr.IP != nil && addr.IP.IsMulticast() {
-			if err := setDefaultMulticastSockopts(fd.pfd.Sysfd); err != nil {
-				return err
-			}
-			addr := *addr
-			switch fd.family {
-			case syscall.AF_INET:
-				addr.IP = IPv4zero
-			case syscall.AF_INET6:
-				addr.IP = IPv6unspecified
-			}
-			laddr = &addr
-		}
-	}
-	var err error
-	var lsa syscall.Sockaddr
-	if lsa, err = laddr.sockaddr(fd.family); err != nil {
-		return err
-	}
-	if ctrlFn != nil {
-		c, err := newRawConn(fd)
-		if err != nil {
-			return err
-		}
-		if err := ctrlFn(fd.ctrlNetwork(), laddr.String(), c); err != nil {
-			return err
-		}
-	}
-	if err = syscall.Bind(fd.pfd.Sysfd, lsa); err != nil {
-		return os.NewSyscallError("bind", err)
-	}
-	if err = fd.init(); err != nil {
-		return err
-	}
-	lsa, _ = syscall.Getsockname(fd.pfd.Sysfd)
-	fd.setAddr(fd.addrFunc()(lsa), nil)
-	return nil
-}
diff --git a/contrib/go/_std_1.18/src/net/sockaddr_posix.go b/contrib/go/_std_1.18/src/net/sockaddr_posix.go
deleted file mode 100644
index c8e91936ad..0000000000
--- a/contrib/go/_std_1.18/src/net/sockaddr_posix.go
+++ /dev/null
@@ -1,34 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris || windows
-
-package net
-
-import (
-	"syscall"
-)
-
-// A sockaddr represents a TCP, UDP, IP or Unix network endpoint
-// address that can be converted into a syscall.Sockaddr.
-type sockaddr interface {
-	Addr
-
-	// family returns the platform-dependent address family
-	// identifier.
-	family() int
-
-	// isWildcard reports whether the address is a wildcard
-	// address.
-	isWildcard() bool
-
-	// sockaddr returns the address converted into a syscall
-	// sockaddr type that implements syscall.Sockaddr
-	// interface. It returns a nil interface when the address is
-	// nil.
-	sockaddr(family int) (syscall.Sockaddr, error)
-
-	// toLocal maps the zero address to a local system address (127.0.0.1 or ::1)
-	toLocal(net string) sockaddr
-}
diff --git a/contrib/go/_std_1.18/src/net/sockopt_posix.go b/contrib/go/_std_1.18/src/net/sockopt_posix.go
deleted file mode 100644
index 645080f988..0000000000
--- a/contrib/go/_std_1.18/src/net/sockopt_posix.go
+++ /dev/null
@@ -1,134 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris || windows
-
-package net
-
-import (
-	"internal/bytealg"
-	"runtime"
-	"syscall"
-)
-
-// Boolean to int.
-func boolint(b bool) int {
-	if b {
-		return 1
-	}
-	return 0
-}
-
-func ipv4AddrToInterface(ip IP) (*Interface, error) {
-	ift, err := Interfaces()
-	if err != nil {
-		return nil, err
-	}
-	for _, ifi := range ift {
-		ifat, err := ifi.Addrs()
-		if err != nil {
-			return nil, err
-		}
-		for _, ifa := range ifat {
-			switch v := ifa.(type) {
-			case *IPAddr:
-				if ip.Equal(v.IP) {
-					return &ifi, nil
-				}
-			case *IPNet:
-				if ip.Equal(v.IP) {
-					return &ifi, nil
-				}
-			}
-		}
-	}
-	if ip.Equal(IPv4zero) {
-		return nil, nil
-	}
-	return nil, errNoSuchInterface
-}
-
-func interfaceToIPv4Addr(ifi *Interface) (IP, error) {
-	if ifi == nil {
-		return IPv4zero, nil
-	}
-	ifat, err := ifi.Addrs()
-	if err != nil {
-		return nil, err
-	}
-	for _, ifa := range ifat {
-		switch v := ifa.(type) {
-		case *IPAddr:
-			if v.IP.To4() != nil {
-				return v.IP, nil
-			}
-		case *IPNet:
-			if v.IP.To4() != nil {
-				return v.IP, nil
-			}
-		}
-	}
-	return nil, errNoSuchInterface
-}
-
-func setIPv4MreqToInterface(mreq *syscall.IPMreq, ifi *Interface) error {
-	if ifi == nil {
-		return nil
-	}
-	ifat, err := ifi.Addrs()
-	if err != nil {
-		return err
-	}
-	for _, ifa := range ifat {
-		switch v := ifa.(type) {
-		case *IPAddr:
-			if a := v.IP.To4(); a != nil {
-				copy(mreq.Interface[:], a)
-				goto done
-			}
-		case *IPNet:
-			if a := v.IP.To4(); a != nil {
-				copy(mreq.Interface[:], a)
-				goto done
-			}
-		}
-	}
-done:
-	if bytealg.Equal(mreq.Multiaddr[:], IPv4zero.To4()) {
-		return errNoSuchMulticastInterface
-	}
-	return nil
-}
-
-func setReadBuffer(fd *netFD, bytes int) error {
-	err := fd.pfd.SetsockoptInt(syscall.SOL_SOCKET, syscall.SO_RCVBUF, bytes)
-	runtime.KeepAlive(fd)
-	return wrapSyscallError("setsockopt", err)
-}
-
-func setWriteBuffer(fd *netFD, bytes int) error {
-	err := fd.pfd.SetsockoptInt(syscall.SOL_SOCKET, syscall.SO_SNDBUF, bytes)
-	runtime.KeepAlive(fd)
-	return wrapSyscallError("setsockopt", err)
-}
-
-func setKeepAlive(fd *netFD, keepalive bool) error {
-	err := fd.pfd.SetsockoptInt(syscall.SOL_SOCKET, syscall.SO_KEEPALIVE, boolint(keepalive))
-	runtime.KeepAlive(fd)
-	return wrapSyscallError("setsockopt", err)
-}
-
-func setLinger(fd *netFD, sec int) error {
-	var l syscall.Linger
-	if sec >= 0 {
-		l.Onoff = 1
-		l.Linger = int32(sec)
-	} else {
-		l.Onoff = 0
-		l.Linger = 0
-	}
-	err := fd.pfd.SetsockoptLinger(syscall.SOL_SOCKET, syscall.SO_LINGER, &l)
-	runtime.KeepAlive(fd)
-	return wrapSyscallError("setsockopt", err)
-}
diff --git a/contrib/go/_std_1.18/src/net/sockoptip_posix.go b/contrib/go/_std_1.18/src/net/sockoptip_posix.go
deleted file mode 100644
index 22031df22c..0000000000
--- a/contrib/go/_std_1.18/src/net/sockoptip_posix.go
+++ /dev/null
@@ -1,49 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris || windows
-
-package net
-
-import (
-	"runtime"
-	"syscall"
-)
-
-func joinIPv4Group(fd *netFD, ifi *Interface, ip IP) error {
-	mreq := &syscall.IPMreq{Multiaddr: [4]byte{ip[0], ip[1], ip[2], ip[3]}}
-	if err := setIPv4MreqToInterface(mreq, ifi); err != nil {
-		return err
-	}
-	err := fd.pfd.SetsockoptIPMreq(syscall.IPPROTO_IP, syscall.IP_ADD_MEMBERSHIP, mreq)
-	runtime.KeepAlive(fd)
-	return wrapSyscallError("setsockopt", err)
-}
-
-func setIPv6MulticastInterface(fd *netFD, ifi *Interface) error {
-	var v int
-	if ifi != nil {
-		v = ifi.Index
-	}
-	err := fd.pfd.SetsockoptInt(syscall.IPPROTO_IPV6, syscall.IPV6_MULTICAST_IF, v)
-	runtime.KeepAlive(fd)
-	return wrapSyscallError("setsockopt", err)
-}
-
-func setIPv6MulticastLoopback(fd *netFD, v bool) error {
-	err := fd.pfd.SetsockoptInt(syscall.IPPROTO_IPV6, syscall.IPV6_MULTICAST_LOOP, boolint(v))
-	runtime.KeepAlive(fd)
-	return wrapSyscallError("setsockopt", err)
-}
-
-func joinIPv6Group(fd *netFD, ifi *Interface, ip IP) error {
-	mreq := &syscall.IPv6Mreq{}
-	copy(mreq.Multiaddr[:], ip)
-	if ifi != nil {
-		mreq.Interface = uint32(ifi.Index)
-	}
-	err := fd.pfd.SetsockoptIPv6Mreq(syscall.IPPROTO_IPV6, syscall.IPV6_JOIN_GROUP, mreq)
-	runtime.KeepAlive(fd)
-	return wrapSyscallError("setsockopt", err)
-}
diff --git a/contrib/go/_std_1.18/src/net/sys_cloexec.go b/contrib/go/_std_1.18/src/net/sys_cloexec.go
deleted file mode 100644
index 26eac5585a..0000000000
--- a/contrib/go/_std_1.18/src/net/sys_cloexec.go
+++ /dev/null
@@ -1,36 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file implements sysSocket for platforms that do not provide a fast path
-// for setting SetNonblock and CloseOnExec.
-
-//go:build aix || darwin || (solaris && !illumos)
-
-package net
-
-import (
-	"internal/poll"
-	"os"
-	"syscall"
-)
-
-// Wrapper around the socket system call that marks the returned file
-// descriptor as nonblocking and close-on-exec.
-func sysSocket(family, sotype, proto int) (int, error) {
-	// See ../syscall/exec_unix.go for description of ForkLock.
-	syscall.ForkLock.RLock()
-	s, err := socketFunc(family, sotype, proto)
-	if err == nil {
-		syscall.CloseOnExec(s)
-	}
-	syscall.ForkLock.RUnlock()
-	if err != nil {
-		return -1, os.NewSyscallError("socket", err)
-	}
-	if err = syscall.SetNonblock(s, true); err != nil {
-		poll.CloseFunc(s)
-		return -1, os.NewSyscallError("setnonblock", err)
-	}
-	return s, nil
-}
diff --git a/contrib/go/_std_1.18/src/net/tcpsock_posix.go b/contrib/go/_std_1.18/src/net/tcpsock_posix.go
deleted file mode 100644
index ed6b18b551..0000000000
--- a/contrib/go/_std_1.18/src/net/tcpsock_posix.go
+++ /dev/null
@@ -1,173 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris || windows
-
-package net
-
-import (
-	"context"
-	"io"
-	"os"
-	"syscall"
-)
-
-func sockaddrToTCP(sa syscall.Sockaddr) Addr {
-	switch sa := sa.(type) {
-	case *syscall.SockaddrInet4:
-		return &TCPAddr{IP: sa.Addr[0:], Port: sa.Port}
-	case *syscall.SockaddrInet6:
-		return &TCPAddr{IP: sa.Addr[0:], Port: sa.Port, Zone: zoneCache.name(int(sa.ZoneId))}
-	}
-	return nil
-}
-
-func (a *TCPAddr) family() int {
-	if a == nil || len(a.IP) <= IPv4len {
-		return syscall.AF_INET
-	}
-	if a.IP.To4() != nil {
-		return syscall.AF_INET
-	}
-	return syscall.AF_INET6
-}
-
-func (a *TCPAddr) sockaddr(family int) (syscall.Sockaddr, error) {
-	if a == nil {
-		return nil, nil
-	}
-	return ipToSockaddr(family, a.IP, a.Port, a.Zone)
-}
-
-func (a *TCPAddr) toLocal(net string) sockaddr {
-	return &TCPAddr{loopbackIP(net), a.Port, a.Zone}
-}
-
-func (c *TCPConn) readFrom(r io.Reader) (int64, error) {
-	if n, err, handled := splice(c.fd, r); handled {
-		return n, err
-	}
-	if n, err, handled := sendFile(c.fd, r); handled {
-		return n, err
-	}
-	return genericReadFrom(c, r)
-}
-
-func (sd *sysDialer) dialTCP(ctx context.Context, laddr, raddr *TCPAddr) (*TCPConn, error) {
-	if testHookDialTCP != nil {
-		return testHookDialTCP(ctx, sd.network, laddr, raddr)
-	}
-	return sd.doDialTCP(ctx, laddr, raddr)
-}
-
-func (sd *sysDialer) doDialTCP(ctx context.Context, laddr, raddr *TCPAddr) (*TCPConn, error) {
-	fd, err := internetSocket(ctx, sd.network, laddr, raddr, syscall.SOCK_STREAM, 0, "dial", sd.Dialer.Control)
-
-	// TCP has a rarely used mechanism called a 'simultaneous connection' in
-	// which Dial("tcp", addr1, addr2) run on the machine at addr1 can
-	// connect to a simultaneous Dial("tcp", addr2, addr1) run on the machine
-	// at addr2, without either machine executing Listen. If laddr == nil,
-	// it means we want the kernel to pick an appropriate originating local
-	// address. Some Linux kernels cycle blindly through a fixed range of
-	// local ports, regardless of destination port. If a kernel happens to
-	// pick local port 50001 as the source for a Dial("tcp", "", "localhost:50001"),
-	// then the Dial will succeed, having simultaneously connected to itself.
-	// This can only happen when we are letting the kernel pick a port (laddr == nil)
-	// and when there is no listener for the destination address.
-	// It's hard to argue this is anything other than a kernel bug. If we
-	// see this happen, rather than expose the buggy effect to users, we
-	// close the fd and try again. If it happens twice more, we relent and
-	// use the result. See also:
-	//	https://golang.org/issue/2690
-	//	https://stackoverflow.com/questions/4949858/
-	//
-	// The opposite can also happen: if we ask the kernel to pick an appropriate
-	// originating local address, sometimes it picks one that is already in use.
-	// So if the error is EADDRNOTAVAIL, we have to try again too, just for
-	// a different reason.
-	//
-	// The kernel socket code is no doubt enjoying watching us squirm.
-	for i := 0; i < 2 && (laddr == nil || laddr.Port == 0) && (selfConnect(fd, err) || spuriousENOTAVAIL(err)); i++ {
-		if err == nil {
-			fd.Close()
-		}
-		fd, err = internetSocket(ctx, sd.network, laddr, raddr, syscall.SOCK_STREAM, 0, "dial", sd.Dialer.Control)
-	}
-
-	if err != nil {
-		return nil, err
-	}
-	return newTCPConn(fd), nil
-}
-
-func selfConnect(fd *netFD, err error) bool {
-	// If the connect failed, we clearly didn't connect to ourselves.
-	if err != nil {
-		return false
-	}
-
-	// The socket constructor can return an fd with raddr nil under certain
-	// unknown conditions. The errors in the calls there to Getpeername
-	// are discarded, but we can't catch the problem there because those
-	// calls are sometimes legally erroneous with a "socket not connected".
-	// Since this code (selfConnect) is already trying to work around
-	// a problem, we make sure if this happens we recognize trouble and
-	// ask the DialTCP routine to try again.
-	// TODO: try to understand what's really going on.
-	if fd.laddr == nil || fd.raddr == nil {
-		return true
-	}
-	l := fd.laddr.(*TCPAddr)
-	r := fd.raddr.(*TCPAddr)
-	return l.Port == r.Port && l.IP.Equal(r.IP)
-}
-
-func spuriousENOTAVAIL(err error) bool {
-	if op, ok := err.(*OpError); ok {
-		err = op.Err
-	}
-	if sys, ok := err.(*os.SyscallError); ok {
-		err = sys.Err
-	}
-	return err == syscall.EADDRNOTAVAIL
-}
-
-func (ln *TCPListener) ok() bool { return ln != nil && ln.fd != nil }
-
-func (ln *TCPListener) accept() (*TCPConn, error) {
-	fd, err := ln.fd.accept()
-	if err != nil {
-		return nil, err
-	}
-	tc := newTCPConn(fd)
-	if ln.lc.KeepAlive >= 0 {
-		setKeepAlive(fd, true)
-		ka := ln.lc.KeepAlive
-		if ln.lc.KeepAlive == 0 {
-			ka = defaultTCPKeepAlive
-		}
-		setKeepAlivePeriod(fd, ka)
-	}
-	return tc, nil
-}
-
-func (ln *TCPListener) close() error {
-	return ln.fd.Close()
-}
-
-func (ln *TCPListener) file() (*os.File, error) {
-	f, err := ln.fd.dup()
-	if err != nil {
-		return nil, err
-	}
-	return f, nil
-}
-
-func (sl *sysListener) listenTCP(ctx context.Context, laddr *TCPAddr) (*TCPListener, error) {
-	fd, err := internetSocket(ctx, sl.network, laddr, nil, syscall.SOCK_STREAM, 0, "listen", sl.ListenConfig.Control)
-	if err != nil {
-		return nil, err
-	}
-	return &TCPListener{fd: fd, lc: sl.ListenConfig}, nil
-}
diff --git a/contrib/go/_std_1.18/src/net/tcpsockopt_posix.go b/contrib/go/_std_1.18/src/net/tcpsockopt_posix.go
deleted file mode 100644
index 73754b1a0f..0000000000
--- a/contrib/go/_std_1.18/src/net/tcpsockopt_posix.go
+++ /dev/null
@@ -1,18 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris || windows
-
-package net
-
-import (
-	"runtime"
-	"syscall"
-)
-
-func setNoDelay(fd *netFD, noDelay bool) error {
-	err := fd.pfd.SetsockoptInt(syscall.IPPROTO_TCP, syscall.TCP_NODELAY, boolint(noDelay))
-	runtime.KeepAlive(fd)
-	return wrapSyscallError("setsockopt", err)
-}
diff --git a/contrib/go/_std_1.18/src/net/textproto/reader.go b/contrib/go/_std_1.18/src/net/textproto/reader.go
deleted file mode 100644
index 157c59b17a..0000000000
--- a/contrib/go/_std_1.18/src/net/textproto/reader.go
+++ /dev/null
@@ -1,790 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package textproto
-
-import (
-	"bufio"
-	"bytes"
-	"fmt"
-	"io"
-	"strconv"
-	"strings"
-	"sync"
-)
-
-// A Reader implements convenience methods for reading requests
-// or responses from a text protocol network connection.
-type Reader struct {
-	R   *bufio.Reader
-	dot *dotReader
-	buf []byte // a re-usable buffer for readContinuedLineSlice
-}
-
-// NewReader returns a new Reader reading from r.
-//
-// To avoid denial of service attacks, the provided bufio.Reader
-// should be reading from an io.LimitReader or similar Reader to bound
-// the size of responses.
-func NewReader(r *bufio.Reader) *Reader {
-	commonHeaderOnce.Do(initCommonHeader)
-	return &Reader{R: r}
-}
-
-// ReadLine reads a single line from r,
-// eliding the final \n or \r\n from the returned string.
-func (r *Reader) ReadLine() (string, error) {
-	line, err := r.readLineSlice()
-	return string(line), err
-}
-
-// ReadLineBytes is like ReadLine but returns a []byte instead of a string.
-func (r *Reader) ReadLineBytes() ([]byte, error) {
-	line, err := r.readLineSlice()
-	if line != nil {
-		buf := make([]byte, len(line))
-		copy(buf, line)
-		line = buf
-	}
-	return line, err
-}
-
-func (r *Reader) readLineSlice() ([]byte, error) {
-	r.closeDot()
-	var line []byte
-	for {
-		l, more, err := r.R.ReadLine()
-		if err != nil {
-			return nil, err
-		}
-		// Avoid the copy if the first call produced a full line.
-		if line == nil && !more {
-			return l, nil
-		}
-		line = append(line, l...)
-		if !more {
-			break
-		}
-	}
-	return line, nil
-}
-
-// ReadContinuedLine reads a possibly continued line from r,
-// eliding the final trailing ASCII white space.
-// Lines after the first are considered continuations if they
-// begin with a space or tab character. In the returned data,
-// continuation lines are separated from the previous line
-// only by a single space: the newline and leading white space
-// are removed.
-//
-// For example, consider this input:
-//
-//	Line 1
-//	  continued...
-//	Line 2
-//
-// The first call to ReadContinuedLine will return "Line 1 continued..."
-// and the second will return "Line 2".
-//
-// Empty lines are never continued.
-//
-func (r *Reader) ReadContinuedLine() (string, error) {
-	line, err := r.readContinuedLineSlice(noValidation)
-	return string(line), err
-}
-
-// trim returns s with leading and trailing spaces and tabs removed.
-// It does not assume Unicode or UTF-8.
-func trim(s []byte) []byte {
-	i := 0
-	for i < len(s) && (s[i] == ' ' || s[i] == '\t') {
-		i++
-	}
-	n := len(s)
-	for n > i && (s[n-1] == ' ' || s[n-1] == '\t') {
-		n--
-	}
-	return s[i:n]
-}
-
-// ReadContinuedLineBytes is like ReadContinuedLine but
-// returns a []byte instead of a string.
-func (r *Reader) ReadContinuedLineBytes() ([]byte, error) {
-	line, err := r.readContinuedLineSlice(noValidation)
-	if line != nil {
-		buf := make([]byte, len(line))
-		copy(buf, line)
-		line = buf
-	}
-	return line, err
-}
-
-// readContinuedLineSlice reads continued lines from the reader buffer,
-// returning a byte slice with all lines. The validateFirstLine function
-// is run on the first read line, and if it returns an error then this
-// error is returned from readContinuedLineSlice.
-func (r *Reader) readContinuedLineSlice(validateFirstLine func([]byte) error) ([]byte, error) {
-	if validateFirstLine == nil {
-		return nil, fmt.Errorf("missing validateFirstLine func")
-	}
-
-	// Read the first line.
-	line, err := r.readLineSlice()
-	if err != nil {
-		return nil, err
-	}
-	if len(line) == 0 { // blank line - no continuation
-		return line, nil
-	}
-
-	if err := validateFirstLine(line); err != nil {
-		return nil, err
-	}
-
-	// Optimistically assume that we have started to buffer the next line
-	// and it starts with an ASCII letter (the next header key), or a blank
-	// line, so we can avoid copying that buffered data around in memory
-	// and skipping over non-existent whitespace.
-	if r.R.Buffered() > 1 {
-		peek, _ := r.R.Peek(2)
-		if len(peek) > 0 && (isASCIILetter(peek[0]) || peek[0] == '\n') ||
-			len(peek) == 2 && peek[0] == '\r' && peek[1] == '\n' {
-			return trim(line), nil
-		}
-	}
-
-	// ReadByte or the next readLineSlice will flush the read buffer;
-	// copy the slice into buf.
-	r.buf = append(r.buf[:0], trim(line)...)
-
-	// Read continuation lines.
-	for r.skipSpace() > 0 {
-		line, err := r.readLineSlice()
-		if err != nil {
-			break
-		}
-		r.buf = append(r.buf, ' ')
-		r.buf = append(r.buf, trim(line)...)
-	}
-	return r.buf, nil
-}
-
-// skipSpace skips R over all spaces and returns the number of bytes skipped.
-func (r *Reader) skipSpace() int {
-	n := 0
-	for {
-		c, err := r.R.ReadByte()
-		if err != nil {
-			// Bufio will keep err until next read.
-			break
-		}
-		if c != ' ' && c != '\t' {
-			r.R.UnreadByte()
-			break
-		}
-		n++
-	}
-	return n
-}
-
-func (r *Reader) readCodeLine(expectCode int) (code int, continued bool, message string, err error) {
-	line, err := r.ReadLine()
-	if err != nil {
-		return
-	}
-	return parseCodeLine(line, expectCode)
-}
-
-func parseCodeLine(line string, expectCode int) (code int, continued bool, message string, err error) {
-	if len(line) < 4 || line[3] != ' ' && line[3] != '-' {
-		err = ProtocolError("short response: " + line)
-		return
-	}
-	continued = line[3] == '-'
-	code, err = strconv.Atoi(line[0:3])
-	if err != nil || code < 100 {
-		err = ProtocolError("invalid response code: " + line)
-		return
-	}
-	message = line[4:]
-	if 1 <= expectCode && expectCode < 10 && code/100 != expectCode ||
-		10 <= expectCode && expectCode < 100 && code/10 != expectCode ||
-		100 <= expectCode && expectCode < 1000 && code != expectCode {
-		err = &Error{code, message}
-	}
-	return
-}
-
-// ReadCodeLine reads a response code line of the form
-//	code message
-// where code is a three-digit status code and the message
-// extends to the rest of the line. An example of such a line is:
-//	220 plan9.bell-labs.com ESMTP
-//
-// If the prefix of the status does not match the digits in expectCode,
-// ReadCodeLine returns with err set to &Error{code, message}.
-// For example, if expectCode is 31, an error will be returned if
-// the status is not in the range [310,319].
-//
-// If the response is multi-line, ReadCodeLine returns an error.
-//
-// An expectCode <= 0 disables the check of the status code.
-//
-func (r *Reader) ReadCodeLine(expectCode int) (code int, message string, err error) {
-	code, continued, message, err := r.readCodeLine(expectCode)
-	if err == nil && continued {
-		err = ProtocolError("unexpected multi-line response: " + message)
-	}
-	return
-}
-
-// ReadResponse reads a multi-line response of the form:
-//
-//	code-message line 1
-//	code-message line 2
-//	...
-//	code message line n
-//
-// where code is a three-digit status code. The first line starts with the
-// code and a hyphen. The response is terminated by a line that starts
-// with the same code followed by a space. Each line in message is
-// separated by a newline (\n).
-//
-// See page 36 of RFC 959 (https://www.ietf.org/rfc/rfc959.txt) for
-// details of another form of response accepted:
-//
-//  code-message line 1
-//  message line 2
-//  ...
-//  code message line n
-//
-// If the prefix of the status does not match the digits in expectCode,
-// ReadResponse returns with err set to &Error{code, message}.
-// For example, if expectCode is 31, an error will be returned if
-// the status is not in the range [310,319].
-//
-// An expectCode <= 0 disables the check of the status code.
-//
-func (r *Reader) ReadResponse(expectCode int) (code int, message string, err error) {
-	code, continued, message, err := r.readCodeLine(expectCode)
-	multi := continued
-	for continued {
-		line, err := r.ReadLine()
-		if err != nil {
-			return 0, "", err
-		}
-
-		var code2 int
-		var moreMessage string
-		code2, continued, moreMessage, err = parseCodeLine(line, 0)
-		if err != nil || code2 != code {
-			message += "\n" + strings.TrimRight(line, "\r\n")
-			continued = true
-			continue
-		}
-		message += "\n" + moreMessage
-	}
-	if err != nil && multi && message != "" {
-		// replace one line error message with all lines (full message)
-		err = &Error{code, message}
-	}
-	return
-}
-
-// DotReader returns a new Reader that satisfies Reads using the
-// decoded text of a dot-encoded block read from r.
-// The returned Reader is only valid until the next call
-// to a method on r.
-//
-// Dot encoding is a common framing used for data blocks
-// in text protocols such as SMTP.  The data consists of a sequence
-// of lines, each of which ends in "\r\n".  The sequence itself
-// ends at a line containing just a dot: ".\r\n".  Lines beginning
-// with a dot are escaped with an additional dot to avoid
-// looking like the end of the sequence.
-//
-// The decoded form returned by the Reader's Read method
-// rewrites the "\r\n" line endings into the simpler "\n",
-// removes leading dot escapes if present, and stops with error io.EOF
-// after consuming (and discarding) the end-of-sequence line.
-func (r *Reader) DotReader() io.Reader {
-	r.closeDot()
-	r.dot = &dotReader{r: r}
-	return r.dot
-}
-
-type dotReader struct {
-	r     *Reader
-	state int
-}
-
-// Read satisfies reads by decoding dot-encoded data read from d.r.
-func (d *dotReader) Read(b []byte) (n int, err error) {
-	// Run data through a simple state machine to
-	// elide leading dots, rewrite trailing \r\n into \n,
-	// and detect ending .\r\n line.
-	const (
-		stateBeginLine = iota // beginning of line; initial state; must be zero
-		stateDot              // read . at beginning of line
-		stateDotCR            // read .\r at beginning of line
-		stateCR               // read \r (possibly at end of line)
-		stateData             // reading data in middle of line
-		stateEOF              // reached .\r\n end marker line
-	)
-	br := d.r.R
-	for n < len(b) && d.state != stateEOF {
-		var c byte
-		c, err = br.ReadByte()
-		if err != nil {
-			if err == io.EOF {
-				err = io.ErrUnexpectedEOF
-			}
-			break
-		}
-		switch d.state {
-		case stateBeginLine:
-			if c == '.' {
-				d.state = stateDot
-				continue
-			}
-			if c == '\r' {
-				d.state = stateCR
-				continue
-			}
-			d.state = stateData
-
-		case stateDot:
-			if c == '\r' {
-				d.state = stateDotCR
-				continue
-			}
-			if c == '\n' {
-				d.state = stateEOF
-				continue
-			}
-			d.state = stateData
-
-		case stateDotCR:
-			if c == '\n' {
-				d.state = stateEOF
-				continue
-			}
-			// Not part of .\r\n.
-			// Consume leading dot and emit saved \r.
-			br.UnreadByte()
-			c = '\r'
-			d.state = stateData
-
-		case stateCR:
-			if c == '\n' {
-				d.state = stateBeginLine
-				break
-			}
-			// Not part of \r\n. Emit saved \r
-			br.UnreadByte()
-			c = '\r'
-			d.state = stateData
-
-		case stateData:
-			if c == '\r' {
-				d.state = stateCR
-				continue
-			}
-			if c == '\n' {
-				d.state = stateBeginLine
-			}
-		}
-		b[n] = c
-		n++
-	}
-	if err == nil && d.state == stateEOF {
-		err = io.EOF
-	}
-	if err != nil && d.r.dot == d {
-		d.r.dot = nil
-	}
-	return
-}
-
-// closeDot drains the current DotReader if any,
-// making sure that it reads until the ending dot line.
-func (r *Reader) closeDot() {
-	if r.dot == nil {
-		return
-	}
-	buf := make([]byte, 128)
-	for r.dot != nil {
-		// When Read reaches EOF or an error,
-		// it will set r.dot == nil.
-		r.dot.Read(buf)
-	}
-}
-
-// ReadDotBytes reads a dot-encoding and returns the decoded data.
-//
-// See the documentation for the DotReader method for details about dot-encoding.
-func (r *Reader) ReadDotBytes() ([]byte, error) {
-	return io.ReadAll(r.DotReader())
-}
-
-// ReadDotLines reads a dot-encoding and returns a slice
-// containing the decoded lines, with the final \r\n or \n elided from each.
-//
-// See the documentation for the DotReader method for details about dot-encoding.
-func (r *Reader) ReadDotLines() ([]string, error) {
-	// We could use ReadDotBytes and then Split it,
-	// but reading a line at a time avoids needing a
-	// large contiguous block of memory and is simpler.
-	var v []string
-	var err error
-	for {
-		var line string
-		line, err = r.ReadLine()
-		if err != nil {
-			if err == io.EOF {
-				err = io.ErrUnexpectedEOF
-			}
-			break
-		}
-
-		// Dot by itself marks end; otherwise cut one dot.
-		if len(line) > 0 && line[0] == '.' {
-			if len(line) == 1 {
-				break
-			}
-			line = line[1:]
-		}
-		v = append(v, line)
-	}
-	return v, err
-}
-
-var colon = []byte(":")
-
-// ReadMIMEHeader reads a MIME-style header from r.
-// The header is a sequence of possibly continued Key: Value lines
-// ending in a blank line.
-// The returned map m maps CanonicalMIMEHeaderKey(key) to a
-// sequence of values in the same order encountered in the input.
-//
-// For example, consider this input:
-//
-//	My-Key: Value 1
-//	Long-Key: Even
-//	       Longer Value
-//	My-Key: Value 2
-//
-// Given that input, ReadMIMEHeader returns the map:
-//
-//	map[string][]string{
-//		"My-Key": {"Value 1", "Value 2"},
-//		"Long-Key": {"Even Longer Value"},
-//	}
-//
-func (r *Reader) ReadMIMEHeader() (MIMEHeader, error) {
-	// Avoid lots of small slice allocations later by allocating one
-	// large one ahead of time which we'll cut up into smaller
-	// slices. If this isn't big enough later, we allocate small ones.
-	var strs []string
-	hint := r.upcomingHeaderNewlines()
-	if hint > 0 {
-		strs = make([]string, hint)
-	}
-
-	m := make(MIMEHeader, hint)
-
-	// The first line cannot start with a leading space.
-	if buf, err := r.R.Peek(1); err == nil && (buf[0] == ' ' || buf[0] == '\t') {
-		line, err := r.readLineSlice()
-		if err != nil {
-			return m, err
-		}
-		return m, ProtocolError("malformed MIME header initial line: " + string(line))
-	}
-
-	for {
-		kv, err := r.readContinuedLineSlice(mustHaveFieldNameColon)
-		if len(kv) == 0 {
-			return m, err
-		}
-
-		// Key ends at first colon.
-		k, v, ok := bytes.Cut(kv, colon)
-		if !ok {
-			return m, ProtocolError("malformed MIME header line: " + string(kv))
-		}
-		key := canonicalMIMEHeaderKey(k)
-
-		// As per RFC 7230 field-name is a token, tokens consist of one or more chars.
-		// We could return a ProtocolError here, but better to be liberal in what we
-		// accept, so if we get an empty key, skip it.
-		if key == "" {
-			continue
-		}
-
-		// Skip initial spaces in value.
-		value := strings.TrimLeft(string(v), " \t")
-
-		vv := m[key]
-		if vv == nil && len(strs) > 0 {
-			// More than likely this will be a single-element key.
-			// Most headers aren't multi-valued.
-			// Set the capacity on strs[0] to 1, so any future append
-			// won't extend the slice into the other strings.
-			vv, strs = strs[:1:1], strs[1:]
-			vv[0] = value
-			m[key] = vv
-		} else {
-			m[key] = append(vv, value)
-		}
-
-		if err != nil {
-			return m, err
-		}
-	}
-}
-
-// noValidation is a no-op validation func for readContinuedLineSlice
-// that permits any lines.
-func noValidation(_ []byte) error { return nil }
-
-// mustHaveFieldNameColon ensures that, per RFC 7230, the
-// field-name is on a single line, so the first line must
-// contain a colon.
-func mustHaveFieldNameColon(line []byte) error {
-	if bytes.IndexByte(line, ':') < 0 {
-		return ProtocolError(fmt.Sprintf("malformed MIME header: missing colon: %q", line))
-	}
-	return nil
-}
-
-var nl = []byte("\n")
-
-// upcomingHeaderNewlines returns an approximation of the number of newlines
-// that will be in this header. If it gets confused, it returns 0.
-func (r *Reader) upcomingHeaderNewlines() (n int) {
-	// Try to determine the 'hint' size.
-	r.R.Peek(1) // force a buffer load if empty
-	s := r.R.Buffered()
-	if s == 0 {
-		return
-	}
-	peek, _ := r.R.Peek(s)
-	return bytes.Count(peek, nl)
-}
-
-// CanonicalMIMEHeaderKey returns the canonical format of the
-// MIME header key s. The canonicalization converts the first
-// letter and any letter following a hyphen to upper case;
-// the rest are converted to lowercase. For example, the
-// canonical key for "accept-encoding" is "Accept-Encoding".
-// MIME header keys are assumed to be ASCII only.
-// If s contains a space or invalid header field bytes, it is
-// returned without modifications.
-func CanonicalMIMEHeaderKey(s string) string {
-	commonHeaderOnce.Do(initCommonHeader)
-
-	// Quick check for canonical encoding.
-	upper := true
-	for i := 0; i < len(s); i++ {
-		c := s[i]
-		if !validHeaderFieldByte(c) {
-			return s
-		}
-		if upper && 'a' <= c && c <= 'z' {
-			return canonicalMIMEHeaderKey([]byte(s))
-		}
-		if !upper && 'A' <= c && c <= 'Z' {
-			return canonicalMIMEHeaderKey([]byte(s))
-		}
-		upper = c == '-'
-	}
-	return s
-}
-
-const toLower = 'a' - 'A'
-
-// validHeaderFieldByte reports whether b is a valid byte in a header
-// field name. RFC 7230 says:
-//   header-field   = field-name ":" OWS field-value OWS
-//   field-name     = token
-//   tchar = "!" / "#" / "$" / "%" / "&" / "'" / "*" / "+" / "-" / "." /
-//           "^" / "_" / "`" / "|" / "~" / DIGIT / ALPHA
-//   token = 1*tchar
-func validHeaderFieldByte(b byte) bool {
-	return int(b) < len(isTokenTable) && isTokenTable[b]
-}
-
-// canonicalMIMEHeaderKey is like CanonicalMIMEHeaderKey but is
-// allowed to mutate the provided byte slice before returning the
-// string.
-//
-// For invalid inputs (if a contains spaces or non-token bytes), a
-// is unchanged and a string copy is returned.
-func canonicalMIMEHeaderKey(a []byte) string {
-	// See if a looks like a header key. If not, return it unchanged.
-	for _, c := range a {
-		if validHeaderFieldByte(c) {
-			continue
-		}
-		// Don't canonicalize.
-		return string(a)
-	}
-
-	upper := true
-	for i, c := range a {
-		// Canonicalize: first letter upper case
-		// and upper case after each dash.
-		// (Host, User-Agent, If-Modified-Since).
-		// MIME headers are ASCII only, so no Unicode issues.
-		if upper && 'a' <= c && c <= 'z' {
-			c -= toLower
-		} else if !upper && 'A' <= c && c <= 'Z' {
-			c += toLower
-		}
-		a[i] = c
-		upper = c == '-' // for next time
-	}
-	// The compiler recognizes m[string(byteSlice)] as a special
-	// case, so a copy of a's bytes into a new string does not
-	// happen in this map lookup:
-	if v := commonHeader[string(a)]; v != "" {
-		return v
-	}
-	return string(a)
-}
-
-// commonHeader interns common header strings.
-var commonHeader map[string]string
-
-var commonHeaderOnce sync.Once
-
-func initCommonHeader() {
-	commonHeader = make(map[string]string)
-	for _, v := range []string{
-		"Accept",
-		"Accept-Charset",
-		"Accept-Encoding",
-		"Accept-Language",
-		"Accept-Ranges",
-		"Cache-Control",
-		"Cc",
-		"Connection",
-		"Content-Id",
-		"Content-Language",
-		"Content-Length",
-		"Content-Transfer-Encoding",
-		"Content-Type",
-		"Cookie",
-		"Date",
-		"Dkim-Signature",
-		"Etag",
-		"Expires",
-		"From",
-		"Host",
-		"If-Modified-Since",
-		"If-None-Match",
-		"In-Reply-To",
-		"Last-Modified",
-		"Location",
-		"Message-Id",
-		"Mime-Version",
-		"Pragma",
-		"Received",
-		"Return-Path",
-		"Server",
-		"Set-Cookie",
-		"Subject",
-		"To",
-		"User-Agent",
-		"Via",
-		"X-Forwarded-For",
-		"X-Imforwards",
-		"X-Powered-By",
-	} {
-		commonHeader[v] = v
-	}
-}
-
-// isTokenTable is a copy of net/http/lex.go's isTokenTable.
-// See https://httpwg.github.io/specs/rfc7230.html#rule.token.separators
-var isTokenTable = [127]bool{
-	'!':  true,
-	'#':  true,
-	'$':  true,
-	'%':  true,
-	'&':  true,
-	'\'': true,
-	'*':  true,
-	'+':  true,
-	'-':  true,
-	'.':  true,
-	'0':  true,
-	'1':  true,
-	'2':  true,
-	'3':  true,
-	'4':  true,
-	'5':  true,
-	'6':  true,
-	'7':  true,
-	'8':  true,
-	'9':  true,
-	'A':  true,
-	'B':  true,
-	'C':  true,
-	'D':  true,
-	'E':  true,
-	'F':  true,
-	'G':  true,
-	'H':  true,
-	'I':  true,
-	'J':  true,
-	'K':  true,
-	'L':  true,
-	'M':  true,
-	'N':  true,
-	'O':  true,
-	'P':  true,
-	'Q':  true,
-	'R':  true,
-	'S':  true,
-	'T':  true,
-	'U':  true,
-	'W':  true,
-	'V':  true,
-	'X':  true,
-	'Y':  true,
-	'Z':  true,
-	'^':  true,
-	'_':  true,
-	'`':  true,
-	'a':  true,
-	'b':  true,
-	'c':  true,
-	'd':  true,
-	'e':  true,
-	'f':  true,
-	'g':  true,
-	'h':  true,
-	'i':  true,
-	'j':  true,
-	'k':  true,
-	'l':  true,
-	'm':  true,
-	'n':  true,
-	'o':  true,
-	'p':  true,
-	'q':  true,
-	'r':  true,
-	's':  true,
-	't':  true,
-	'u':  true,
-	'v':  true,
-	'w':  true,
-	'x':  true,
-	'y':  true,
-	'z':  true,
-	'|':  true,
-	'~':  true,
-}
diff --git a/contrib/go/_std_1.18/src/net/textproto/textproto.go b/contrib/go/_std_1.18/src/net/textproto/textproto.go
deleted file mode 100644
index cc1a847e4e..0000000000
--- a/contrib/go/_std_1.18/src/net/textproto/textproto.go
+++ /dev/null
@@ -1,154 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package textproto implements generic support for text-based request/response
-// protocols in the style of HTTP, NNTP, and SMTP.
-//
-// The package provides:
-//
-// Error, which represents a numeric error response from
-// a server.
-//
-// Pipeline, to manage pipelined requests and responses
-// in a client.
-//
-// Reader, to read numeric response code lines,
-// key: value headers, lines wrapped with leading spaces
-// on continuation lines, and whole text blocks ending
-// with a dot on a line by itself.
-//
-// Writer, to write dot-encoded text blocks.
-//
-// Conn, a convenient packaging of Reader, Writer, and Pipeline for use
-// with a single network connection.
-//
-package textproto
-
-import (
-	"bufio"
-	"fmt"
-	"io"
-	"net"
-)
-
-// An Error represents a numeric error response from a server.
-type Error struct {
-	Code int
-	Msg  string
-}
-
-func (e *Error) Error() string {
-	return fmt.Sprintf("%03d %s", e.Code, e.Msg)
-}
-
-// A ProtocolError describes a protocol violation such
-// as an invalid response or a hung-up connection.
-type ProtocolError string
-
-func (p ProtocolError) Error() string {
-	return string(p)
-}
-
-// A Conn represents a textual network protocol connection.
-// It consists of a Reader and Writer to manage I/O
-// and a Pipeline to sequence concurrent requests on the connection.
-// These embedded types carry methods with them;
-// see the documentation of those types for details.
-type Conn struct {
-	Reader
-	Writer
-	Pipeline
-	conn io.ReadWriteCloser
-}
-
-// NewConn returns a new Conn using conn for I/O.
-func NewConn(conn io.ReadWriteCloser) *Conn {
-	return &Conn{
-		Reader: Reader{R: bufio.NewReader(conn)},
-		Writer: Writer{W: bufio.NewWriter(conn)},
-		conn:   conn,
-	}
-}
-
-// Close closes the connection.
-func (c *Conn) Close() error {
-	return c.conn.Close()
-}
-
-// Dial connects to the given address on the given network using net.Dial
-// and then returns a new Conn for the connection.
-func Dial(network, addr string) (*Conn, error) {
-	c, err := net.Dial(network, addr)
-	if err != nil {
-		return nil, err
-	}
-	return NewConn(c), nil
-}
-
-// Cmd is a convenience method that sends a command after
-// waiting its turn in the pipeline. The command text is the
-// result of formatting format with args and appending \r\n.
-// Cmd returns the id of the command, for use with StartResponse and EndResponse.
-//
-// For example, a client might run a HELP command that returns a dot-body
-// by using:
-//
-//	id, err := c.Cmd("HELP")
-//	if err != nil {
-//		return nil, err
-//	}
-//
-//	c.StartResponse(id)
-//	defer c.EndResponse(id)
-//
-//	if _, _, err = c.ReadCodeLine(110); err != nil {
-//		return nil, err
-//	}
-//	text, err := c.ReadDotBytes()
-//	if err != nil {
-//		return nil, err
-//	}
-//	return c.ReadCodeLine(250)
-//
-func (c *Conn) Cmd(format string, args ...any) (id uint, err error) {
-	id = c.Next()
-	c.StartRequest(id)
-	err = c.PrintfLine(format, args...)
-	c.EndRequest(id)
-	if err != nil {
-		return 0, err
-	}
-	return id, nil
-}
-
-// TrimString returns s without leading and trailing ASCII space.
-func TrimString(s string) string {
-	for len(s) > 0 && isASCIISpace(s[0]) {
-		s = s[1:]
-	}
-	for len(s) > 0 && isASCIISpace(s[len(s)-1]) {
-		s = s[:len(s)-1]
-	}
-	return s
-}
-
-// TrimBytes returns b without leading and trailing ASCII space.
-func TrimBytes(b []byte) []byte {
-	for len(b) > 0 && isASCIISpace(b[0]) {
-		b = b[1:]
-	}
-	for len(b) > 0 && isASCIISpace(b[len(b)-1]) {
-		b = b[:len(b)-1]
-	}
-	return b
-}
-
-func isASCIISpace(b byte) bool {
-	return b == ' ' || b == '\t' || b == '\n' || b == '\r'
-}
-
-func isASCIILetter(b byte) bool {
-	b |= 0x20 // make lower case
-	return 'a' <= b && b <= 'z'
-}
diff --git a/contrib/go/_std_1.18/src/net/udpsock.go b/contrib/go/_std_1.18/src/net/udpsock.go
deleted file mode 100644
index 6d29a39edf..0000000000
--- a/contrib/go/_std_1.18/src/net/udpsock.go
+++ /dev/null
@@ -1,364 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package net
-
-import (
-	"context"
-	"internal/itoa"
-	"net/netip"
-	"syscall"
-)
-
-// BUG(mikio): On Plan 9, the ReadMsgUDP and
-// WriteMsgUDP methods of UDPConn are not implemented.
-
-// BUG(mikio): On Windows, the File method of UDPConn is not
-// implemented.
-
-// BUG(mikio): On JS, methods and functions related to UDPConn are not
-// implemented.
-
-// UDPAddr represents the address of a UDP end point.
-type UDPAddr struct {
-	IP   IP
-	Port int
-	Zone string // IPv6 scoped addressing zone
-}
-
-// AddrPort returns the UDPAddr a as a netip.AddrPort.
-//
-// If a.Port does not fit in a uint16, it's silently truncated.
-//
-// If a is nil, a zero value is returned.
-func (a *UDPAddr) AddrPort() netip.AddrPort {
-	if a == nil {
-		return netip.AddrPort{}
-	}
-	na, _ := netip.AddrFromSlice(a.IP)
-	na = na.WithZone(a.Zone)
-	return netip.AddrPortFrom(na, uint16(a.Port))
-}
-
-// Network returns the address's network name, "udp".
-func (a *UDPAddr) Network() string { return "udp" }
-
-func (a *UDPAddr) String() string {
-	if a == nil {
-		return "<nil>"
-	}
-	ip := ipEmptyString(a.IP)
-	if a.Zone != "" {
-		return JoinHostPort(ip+"%"+a.Zone, itoa.Itoa(a.Port))
-	}
-	return JoinHostPort(ip, itoa.Itoa(a.Port))
-}
-
-func (a *UDPAddr) isWildcard() bool {
-	if a == nil || a.IP == nil {
-		return true
-	}
-	return a.IP.IsUnspecified()
-}
-
-func (a *UDPAddr) opAddr() Addr {
-	if a == nil {
-		return nil
-	}
-	return a
-}
-
-// ResolveUDPAddr returns an address of UDP end point.
-//
-// The network must be a UDP network name.
-//
-// If the host in the address parameter is not a literal IP address or
-// the port is not a literal port number, ResolveUDPAddr resolves the
-// address to an address of UDP end point.
-// Otherwise, it parses the address as a pair of literal IP address
-// and port number.
-// The address parameter can use a host name, but this is not
-// recommended, because it will return at most one of the host name's
-// IP addresses.
-//
-// See func Dial for a description of the network and address
-// parameters.
-func ResolveUDPAddr(network, address string) (*UDPAddr, error) {
-	switch network {
-	case "udp", "udp4", "udp6":
-	case "": // a hint wildcard for Go 1.0 undocumented behavior
-		network = "udp"
-	default:
-		return nil, UnknownNetworkError(network)
-	}
-	addrs, err := DefaultResolver.internetAddrList(context.Background(), network, address)
-	if err != nil {
-		return nil, err
-	}
-	return addrs.forResolve(network, address).(*UDPAddr), nil
-}
-
-// UDPAddrFromAddrPort returns addr as a UDPAddr. If addr.IsValid() is false,
-// then the returned UDPAddr will contain a nil IP field, indicating an
-// address family-agnostic unspecified address.
-func UDPAddrFromAddrPort(addr netip.AddrPort) *UDPAddr {
-	return &UDPAddr{
-		IP:   addr.Addr().AsSlice(),
-		Zone: addr.Addr().Zone(),
-		Port: int(addr.Port()),
-	}
-}
-
-// An addrPortUDPAddr is a netip.AddrPort-based UDP address that satisfies the Addr interface.
-type addrPortUDPAddr struct {
-	netip.AddrPort
-}
-
-func (addrPortUDPAddr) Network() string { return "udp" }
-
-// UDPConn is the implementation of the Conn and PacketConn interfaces
-// for UDP network connections.
-type UDPConn struct {
-	conn
-}
-
-// SyscallConn returns a raw network connection.
-// This implements the syscall.Conn interface.
-func (c *UDPConn) SyscallConn() (syscall.RawConn, error) {
-	if !c.ok() {
-		return nil, syscall.EINVAL
-	}
-	return newRawConn(c.fd)
-}
-
-// ReadFromUDP acts like ReadFrom but returns a UDPAddr.
-func (c *UDPConn) ReadFromUDP(b []byte) (n int, addr *UDPAddr, err error) {
-	// This function is designed to allow the caller to control the lifetime
-	// of the returned *UDPAddr and thereby prevent an allocation.
-	// See https://blog.filippo.io/efficient-go-apis-with-the-inliner/.
-	// The real work is done by readFromUDP, below.
-	return c.readFromUDP(b, &UDPAddr{})
-}
-
-// readFromUDP implements ReadFromUDP.
-func (c *UDPConn) readFromUDP(b []byte, addr *UDPAddr) (int, *UDPAddr, error) {
-	if !c.ok() {
-		return 0, nil, syscall.EINVAL
-	}
-	n, addr, err := c.readFrom(b, addr)
-	if err != nil {
-		err = &OpError{Op: "read", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
-	}
-	return n, addr, err
-}
-
-// ReadFrom implements the PacketConn ReadFrom method.
-func (c *UDPConn) ReadFrom(b []byte) (int, Addr, error) {
-	n, addr, err := c.readFromUDP(b, &UDPAddr{})
-	if addr == nil {
-		// Return Addr(nil), not Addr(*UDPConn(nil)).
-		return n, nil, err
-	}
-	return n, addr, err
-}
-
-// ReadFromUDPAddrPort acts like ReadFrom but returns a netip.AddrPort.
-func (c *UDPConn) ReadFromUDPAddrPort(b []byte) (n int, addr netip.AddrPort, err error) {
-	if !c.ok() {
-		return 0, netip.AddrPort{}, syscall.EINVAL
-	}
-	n, addr, err = c.readFromAddrPort(b)
-	if err != nil {
-		err = &OpError{Op: "read", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
-	}
-	return n, addr, err
-}
-
-// ReadMsgUDP reads a message from c, copying the payload into b and
-// the associated out-of-band data into oob. It returns the number of
-// bytes copied into b, the number of bytes copied into oob, the flags
-// that were set on the message and the source address of the message.
-//
-// The packages golang.org/x/net/ipv4 and golang.org/x/net/ipv6 can be
-// used to manipulate IP-level socket options in oob.
-func (c *UDPConn) ReadMsgUDP(b, oob []byte) (n, oobn, flags int, addr *UDPAddr, err error) {
-	var ap netip.AddrPort
-	n, oobn, flags, ap, err = c.ReadMsgUDPAddrPort(b, oob)
-	if ap.IsValid() {
-		addr = UDPAddrFromAddrPort(ap)
-	}
-	return
-}
-
-// ReadMsgUDPAddrPort is like ReadMsgUDP but returns an netip.AddrPort instead of a UDPAddr.
-func (c *UDPConn) ReadMsgUDPAddrPort(b, oob []byte) (n, oobn, flags int, addr netip.AddrPort, err error) {
-	if !c.ok() {
-		return 0, 0, 0, netip.AddrPort{}, syscall.EINVAL
-	}
-	n, oobn, flags, addr, err = c.readMsg(b, oob)
-	if err != nil {
-		err = &OpError{Op: "read", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
-	}
-	return
-}
-
-// WriteToUDP acts like WriteTo but takes a UDPAddr.
-func (c *UDPConn) WriteToUDP(b []byte, addr *UDPAddr) (int, error) {
-	if !c.ok() {
-		return 0, syscall.EINVAL
-	}
-	n, err := c.writeTo(b, addr)
-	if err != nil {
-		err = &OpError{Op: "write", Net: c.fd.net, Source: c.fd.laddr, Addr: addr.opAddr(), Err: err}
-	}
-	return n, err
-}
-
-// WriteToUDPAddrPort acts like WriteTo but takes a netip.AddrPort.
-func (c *UDPConn) WriteToUDPAddrPort(b []byte, addr netip.AddrPort) (int, error) {
-	if !c.ok() {
-		return 0, syscall.EINVAL
-	}
-	n, err := c.writeToAddrPort(b, addr)
-	if err != nil {
-		err = &OpError{Op: "write", Net: c.fd.net, Source: c.fd.laddr, Addr: addrPortUDPAddr{addr}, Err: err}
-	}
-	return n, err
-}
-
-// WriteTo implements the PacketConn WriteTo method.
-func (c *UDPConn) WriteTo(b []byte, addr Addr) (int, error) {
-	if !c.ok() {
-		return 0, syscall.EINVAL
-	}
-	a, ok := addr.(*UDPAddr)
-	if !ok {
-		return 0, &OpError{Op: "write", Net: c.fd.net, Source: c.fd.laddr, Addr: addr, Err: syscall.EINVAL}
-	}
-	n, err := c.writeTo(b, a)
-	if err != nil {
-		err = &OpError{Op: "write", Net: c.fd.net, Source: c.fd.laddr, Addr: a.opAddr(), Err: err}
-	}
-	return n, err
-}
-
-// WriteMsgUDP writes a message to addr via c if c isn't connected, or
-// to c's remote address if c is connected (in which case addr must be
-// nil). The payload is copied from b and the associated out-of-band
-// data is copied from oob. It returns the number of payload and
-// out-of-band bytes written.
-//
-// The packages golang.org/x/net/ipv4 and golang.org/x/net/ipv6 can be
-// used to manipulate IP-level socket options in oob.
-func (c *UDPConn) WriteMsgUDP(b, oob []byte, addr *UDPAddr) (n, oobn int, err error) {
-	if !c.ok() {
-		return 0, 0, syscall.EINVAL
-	}
-	n, oobn, err = c.writeMsg(b, oob, addr)
-	if err != nil {
-		err = &OpError{Op: "write", Net: c.fd.net, Source: c.fd.laddr, Addr: addr.opAddr(), Err: err}
-	}
-	return
-}
-
-// WriteMsgUDPAddrPort is like WriteMsgUDP but takes a netip.AddrPort instead of a UDPAddr.
-func (c *UDPConn) WriteMsgUDPAddrPort(b, oob []byte, addr netip.AddrPort) (n, oobn int, err error) {
-	if !c.ok() {
-		return 0, 0, syscall.EINVAL
-	}
-	n, oobn, err = c.writeMsgAddrPort(b, oob, addr)
-	if err != nil {
-		err = &OpError{Op: "write", Net: c.fd.net, Source: c.fd.laddr, Addr: addrPortUDPAddr{addr}, Err: err}
-	}
-	return
-}
-
-func newUDPConn(fd *netFD) *UDPConn { return &UDPConn{conn{fd}} }
-
-// DialUDP acts like Dial for UDP networks.
-//
-// The network must be a UDP network name; see func Dial for details.
-//
-// If laddr is nil, a local address is automatically chosen.
-// If the IP field of raddr is nil or an unspecified IP address, the
-// local system is assumed.
-func DialUDP(network string, laddr, raddr *UDPAddr) (*UDPConn, error) {
-	switch network {
-	case "udp", "udp4", "udp6":
-	default:
-		return nil, &OpError{Op: "dial", Net: network, Source: laddr.opAddr(), Addr: raddr.opAddr(), Err: UnknownNetworkError(network)}
-	}
-	if raddr == nil {
-		return nil, &OpError{Op: "dial", Net: network, Source: laddr.opAddr(), Addr: nil, Err: errMissingAddress}
-	}
-	sd := &sysDialer{network: network, address: raddr.String()}
-	c, err := sd.dialUDP(context.Background(), laddr, raddr)
-	if err != nil {
-		return nil, &OpError{Op: "dial", Net: network, Source: laddr.opAddr(), Addr: raddr.opAddr(), Err: err}
-	}
-	return c, nil
-}
-
-// ListenUDP acts like ListenPacket for UDP networks.
-//
-// The network must be a UDP network name; see func Dial for details.
-//
-// If the IP field of laddr is nil or an unspecified IP address,
-// ListenUDP listens on all available IP addresses of the local system
-// except multicast IP addresses.
-// If the Port field of laddr is 0, a port number is automatically
-// chosen.
-func ListenUDP(network string, laddr *UDPAddr) (*UDPConn, error) {
-	switch network {
-	case "udp", "udp4", "udp6":
-	default:
-		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: laddr.opAddr(), Err: UnknownNetworkError(network)}
-	}
-	if laddr == nil {
-		laddr = &UDPAddr{}
-	}
-	sl := &sysListener{network: network, address: laddr.String()}
-	c, err := sl.listenUDP(context.Background(), laddr)
-	if err != nil {
-		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: laddr.opAddr(), Err: err}
-	}
-	return c, nil
-}
-
-// ListenMulticastUDP acts like ListenPacket for UDP networks but
-// takes a group address on a specific network interface.
-//
-// The network must be a UDP network name; see func Dial for details.
-//
-// ListenMulticastUDP listens on all available IP addresses of the
-// local system including the group, multicast IP address.
-// If ifi is nil, ListenMulticastUDP uses the system-assigned
-// multicast interface, although this is not recommended because the
-// assignment depends on platforms and sometimes it might require
-// routing configuration.
-// If the Port field of gaddr is 0, a port number is automatically
-// chosen.
-//
-// ListenMulticastUDP is just for convenience of simple, small
-// applications. There are golang.org/x/net/ipv4 and
-// golang.org/x/net/ipv6 packages for general purpose uses.
-//
-// Note that ListenMulticastUDP will set the IP_MULTICAST_LOOP socket option
-// to 0 under IPPROTO_IP, to disable loopback of multicast packets.
-func ListenMulticastUDP(network string, ifi *Interface, gaddr *UDPAddr) (*UDPConn, error) {
-	switch network {
-	case "udp", "udp4", "udp6":
-	default:
-		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: gaddr.opAddr(), Err: UnknownNetworkError(network)}
-	}
-	if gaddr == nil || gaddr.IP == nil {
-		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: gaddr.opAddr(), Err: errMissingAddress}
-	}
-	sl := &sysListener{network: network, address: gaddr.String()}
-	c, err := sl.listenMulticastUDP(context.Background(), ifi, gaddr)
-	if err != nil {
-		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: gaddr.opAddr(), Err: err}
-	}
-	return c, nil
-}
diff --git a/contrib/go/_std_1.18/src/net/udpsock_posix.go b/contrib/go/_std_1.18/src/net/udpsock_posix.go
deleted file mode 100644
index 6544397673..0000000000
--- a/contrib/go/_std_1.18/src/net/udpsock_posix.go
+++ /dev/null
@@ -1,269 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris || windows
-
-package net
-
-import (
-	"context"
-	"net/netip"
-	"syscall"
-)
-
-func sockaddrToUDP(sa syscall.Sockaddr) Addr {
-	switch sa := sa.(type) {
-	case *syscall.SockaddrInet4:
-		return &UDPAddr{IP: sa.Addr[0:], Port: sa.Port}
-	case *syscall.SockaddrInet6:
-		return &UDPAddr{IP: sa.Addr[0:], Port: sa.Port, Zone: zoneCache.name(int(sa.ZoneId))}
-	}
-	return nil
-}
-
-func (a *UDPAddr) family() int {
-	if a == nil || len(a.IP) <= IPv4len {
-		return syscall.AF_INET
-	}
-	if a.IP.To4() != nil {
-		return syscall.AF_INET
-	}
-	return syscall.AF_INET6
-}
-
-func (a *UDPAddr) sockaddr(family int) (syscall.Sockaddr, error) {
-	if a == nil {
-		return nil, nil
-	}
-	return ipToSockaddr(family, a.IP, a.Port, a.Zone)
-}
-
-func (a *UDPAddr) toLocal(net string) sockaddr {
-	return &UDPAddr{loopbackIP(net), a.Port, a.Zone}
-}
-
-func (c *UDPConn) readFrom(b []byte, addr *UDPAddr) (int, *UDPAddr, error) {
-	var n int
-	var err error
-	switch c.fd.family {
-	case syscall.AF_INET:
-		var from syscall.SockaddrInet4
-		n, err = c.fd.readFromInet4(b, &from)
-		if err == nil {
-			ip := from.Addr // copy from.Addr; ip escapes, so this line allocates 4 bytes
-			*addr = UDPAddr{IP: ip[:], Port: from.Port}
-		}
-	case syscall.AF_INET6:
-		var from syscall.SockaddrInet6
-		n, err = c.fd.readFromInet6(b, &from)
-		if err == nil {
-			ip := from.Addr // copy from.Addr; ip escapes, so this line allocates 16 bytes
-			*addr = UDPAddr{IP: ip[:], Port: from.Port, Zone: zoneCache.name(int(from.ZoneId))}
-		}
-	}
-	if err != nil {
-		// No sockaddr, so don't return UDPAddr.
-		addr = nil
-	}
-	return n, addr, err
-}
-
-func (c *UDPConn) readFromAddrPort(b []byte) (n int, addr netip.AddrPort, err error) {
-	var ip netip.Addr
-	var port int
-	switch c.fd.family {
-	case syscall.AF_INET:
-		var from syscall.SockaddrInet4
-		n, err = c.fd.readFromInet4(b, &from)
-		if err == nil {
-			ip = netip.AddrFrom4(from.Addr)
-			port = from.Port
-		}
-	case syscall.AF_INET6:
-		var from syscall.SockaddrInet6
-		n, err = c.fd.readFromInet6(b, &from)
-		if err == nil {
-			ip = netip.AddrFrom16(from.Addr).WithZone(zoneCache.name(int(from.ZoneId)))
-			port = from.Port
-		}
-	}
-	if err == nil {
-		addr = netip.AddrPortFrom(ip, uint16(port))
-	}
-	return n, addr, err
-}
-
-func (c *UDPConn) readMsg(b, oob []byte) (n, oobn, flags int, addr netip.AddrPort, err error) {
-	switch c.fd.family {
-	case syscall.AF_INET:
-		var sa syscall.SockaddrInet4
-		n, oobn, flags, err = c.fd.readMsgInet4(b, oob, 0, &sa)
-		ip := netip.AddrFrom4(sa.Addr)
-		addr = netip.AddrPortFrom(ip, uint16(sa.Port))
-	case syscall.AF_INET6:
-		var sa syscall.SockaddrInet6
-		n, oobn, flags, err = c.fd.readMsgInet6(b, oob, 0, &sa)
-		ip := netip.AddrFrom16(sa.Addr).WithZone(zoneCache.name(int(sa.ZoneId)))
-		addr = netip.AddrPortFrom(ip, uint16(sa.Port))
-	}
-	return
-}
-
-func (c *UDPConn) writeTo(b []byte, addr *UDPAddr) (int, error) {
-	if c.fd.isConnected {
-		return 0, ErrWriteToConnected
-	}
-	if addr == nil {
-		return 0, errMissingAddress
-	}
-
-	switch c.fd.family {
-	case syscall.AF_INET:
-		sa, err := ipToSockaddrInet4(addr.IP, addr.Port)
-		if err != nil {
-			return 0, err
-		}
-		return c.fd.writeToInet4(b, &sa)
-	case syscall.AF_INET6:
-		sa, err := ipToSockaddrInet6(addr.IP, addr.Port, addr.Zone)
-		if err != nil {
-			return 0, err
-		}
-		return c.fd.writeToInet6(b, &sa)
-	default:
-		return 0, &AddrError{Err: "invalid address family", Addr: addr.IP.String()}
-	}
-}
-
-func (c *UDPConn) writeToAddrPort(b []byte, addr netip.AddrPort) (int, error) {
-	if c.fd.isConnected {
-		return 0, ErrWriteToConnected
-	}
-	if !addr.IsValid() {
-		return 0, errMissingAddress
-	}
-
-	switch c.fd.family {
-	case syscall.AF_INET:
-		sa, err := addrPortToSockaddrInet4(addr)
-		if err != nil {
-			return 0, err
-		}
-		return c.fd.writeToInet4(b, &sa)
-	case syscall.AF_INET6:
-		sa, err := addrPortToSockaddrInet6(addr)
-		if err != nil {
-			return 0, err
-		}
-		return c.fd.writeToInet6(b, &sa)
-	default:
-		return 0, &AddrError{Err: "invalid address family", Addr: addr.Addr().String()}
-	}
-}
-
-func (c *UDPConn) writeMsg(b, oob []byte, addr *UDPAddr) (n, oobn int, err error) {
-	if c.fd.isConnected && addr != nil {
-		return 0, 0, ErrWriteToConnected
-	}
-	if !c.fd.isConnected && addr == nil {
-		return 0, 0, errMissingAddress
-	}
-	sa, err := addr.sockaddr(c.fd.family)
-	if err != nil {
-		return 0, 0, err
-	}
-	return c.fd.writeMsg(b, oob, sa)
-}
-
-func (c *UDPConn) writeMsgAddrPort(b, oob []byte, addr netip.AddrPort) (n, oobn int, err error) {
-	if c.fd.isConnected && addr.IsValid() {
-		return 0, 0, ErrWriteToConnected
-	}
-	if !c.fd.isConnected && !addr.IsValid() {
-		return 0, 0, errMissingAddress
-	}
-
-	switch c.fd.family {
-	case syscall.AF_INET:
-		sa, err := addrPortToSockaddrInet4(addr)
-		if err != nil {
-			return 0, 0, err
-		}
-		return c.fd.writeMsgInet4(b, oob, &sa)
-	case syscall.AF_INET6:
-		sa, err := addrPortToSockaddrInet6(addr)
-		if err != nil {
-			return 0, 0, err
-		}
-		return c.fd.writeMsgInet6(b, oob, &sa)
-	default:
-		return 0, 0, &AddrError{Err: "invalid address family", Addr: addr.Addr().String()}
-	}
-}
-
-func (sd *sysDialer) dialUDP(ctx context.Context, laddr, raddr *UDPAddr) (*UDPConn, error) {
-	fd, err := internetSocket(ctx, sd.network, laddr, raddr, syscall.SOCK_DGRAM, 0, "dial", sd.Dialer.Control)
-	if err != nil {
-		return nil, err
-	}
-	return newUDPConn(fd), nil
-}
-
-func (sl *sysListener) listenUDP(ctx context.Context, laddr *UDPAddr) (*UDPConn, error) {
-	fd, err := internetSocket(ctx, sl.network, laddr, nil, syscall.SOCK_DGRAM, 0, "listen", sl.ListenConfig.Control)
-	if err != nil {
-		return nil, err
-	}
-	return newUDPConn(fd), nil
-}
-
-func (sl *sysListener) listenMulticastUDP(ctx context.Context, ifi *Interface, gaddr *UDPAddr) (*UDPConn, error) {
-	fd, err := internetSocket(ctx, sl.network, gaddr, nil, syscall.SOCK_DGRAM, 0, "listen", sl.ListenConfig.Control)
-	if err != nil {
-		return nil, err
-	}
-	c := newUDPConn(fd)
-	if ip4 := gaddr.IP.To4(); ip4 != nil {
-		if err := listenIPv4MulticastUDP(c, ifi, ip4); err != nil {
-			c.Close()
-			return nil, err
-		}
-	} else {
-		if err := listenIPv6MulticastUDP(c, ifi, gaddr.IP); err != nil {
-			c.Close()
-			return nil, err
-		}
-	}
-	return c, nil
-}
-
-func listenIPv4MulticastUDP(c *UDPConn, ifi *Interface, ip IP) error {
-	if ifi != nil {
-		if err := setIPv4MulticastInterface(c.fd, ifi); err != nil {
-			return err
-		}
-	}
-	if err := setIPv4MulticastLoopback(c.fd, false); err != nil {
-		return err
-	}
-	if err := joinIPv4Group(c.fd, ifi, ip); err != nil {
-		return err
-	}
-	return nil
-}
-
-func listenIPv6MulticastUDP(c *UDPConn, ifi *Interface, ip IP) error {
-	if ifi != nil {
-		if err := setIPv6MulticastInterface(c.fd, ifi); err != nil {
-			return err
-		}
-	}
-	if err := setIPv6MulticastLoopback(c.fd, false); err != nil {
-		return err
-	}
-	if err := joinIPv6Group(c.fd, ifi, ip); err != nil {
-		return err
-	}
-	return nil
-}
diff --git a/contrib/go/_std_1.18/src/net/unixsock_posix.go b/contrib/go/_std_1.18/src/net/unixsock_posix.go
deleted file mode 100644
index 1b69df53bf..0000000000
--- a/contrib/go/_std_1.18/src/net/unixsock_posix.go
+++ /dev/null
@@ -1,227 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris || windows
-
-package net
-
-import (
-	"context"
-	"errors"
-	"os"
-	"syscall"
-)
-
-func unixSocket(ctx context.Context, net string, laddr, raddr sockaddr, mode string, ctrlFn func(string, string, syscall.RawConn) error) (*netFD, error) {
-	var sotype int
-	switch net {
-	case "unix":
-		sotype = syscall.SOCK_STREAM
-	case "unixgram":
-		sotype = syscall.SOCK_DGRAM
-	case "unixpacket":
-		sotype = syscall.SOCK_SEQPACKET
-	default:
-		return nil, UnknownNetworkError(net)
-	}
-
-	switch mode {
-	case "dial":
-		if laddr != nil && laddr.isWildcard() {
-			laddr = nil
-		}
-		if raddr != nil && raddr.isWildcard() {
-			raddr = nil
-		}
-		if raddr == nil && (sotype != syscall.SOCK_DGRAM || laddr == nil) {
-			return nil, errMissingAddress
-		}
-	case "listen":
-	default:
-		return nil, errors.New("unknown mode: " + mode)
-	}
-
-	fd, err := socket(ctx, net, syscall.AF_UNIX, sotype, 0, false, laddr, raddr, ctrlFn)
-	if err != nil {
-		return nil, err
-	}
-	return fd, nil
-}
-
-func sockaddrToUnix(sa syscall.Sockaddr) Addr {
-	if s, ok := sa.(*syscall.SockaddrUnix); ok {
-		return &UnixAddr{Name: s.Name, Net: "unix"}
-	}
-	return nil
-}
-
-func sockaddrToUnixgram(sa syscall.Sockaddr) Addr {
-	if s, ok := sa.(*syscall.SockaddrUnix); ok {
-		return &UnixAddr{Name: s.Name, Net: "unixgram"}
-	}
-	return nil
-}
-
-func sockaddrToUnixpacket(sa syscall.Sockaddr) Addr {
-	if s, ok := sa.(*syscall.SockaddrUnix); ok {
-		return &UnixAddr{Name: s.Name, Net: "unixpacket"}
-	}
-	return nil
-}
-
-func sotypeToNet(sotype int) string {
-	switch sotype {
-	case syscall.SOCK_STREAM:
-		return "unix"
-	case syscall.SOCK_DGRAM:
-		return "unixgram"
-	case syscall.SOCK_SEQPACKET:
-		return "unixpacket"
-	default:
-		panic("sotypeToNet unknown socket type")
-	}
-}
-
-func (a *UnixAddr) family() int {
-	return syscall.AF_UNIX
-}
-
-func (a *UnixAddr) sockaddr(family int) (syscall.Sockaddr, error) {
-	if a == nil {
-		return nil, nil
-	}
-	return &syscall.SockaddrUnix{Name: a.Name}, nil
-}
-
-func (a *UnixAddr) toLocal(net string) sockaddr {
-	return a
-}
-
-func (c *UnixConn) readFrom(b []byte) (int, *UnixAddr, error) {
-	var addr *UnixAddr
-	n, sa, err := c.fd.readFrom(b)
-	switch sa := sa.(type) {
-	case *syscall.SockaddrUnix:
-		if sa.Name != "" {
-			addr = &UnixAddr{Name: sa.Name, Net: sotypeToNet(c.fd.sotype)}
-		}
-	}
-	return n, addr, err
-}
-
-func (c *UnixConn) readMsg(b, oob []byte) (n, oobn, flags int, addr *UnixAddr, err error) {
-	var sa syscall.Sockaddr
-	n, oobn, flags, sa, err = c.fd.readMsg(b, oob, readMsgFlags)
-	if readMsgFlags == 0 && err == nil && oobn > 0 {
-		setReadMsgCloseOnExec(oob[:oobn])
-	}
-
-	switch sa := sa.(type) {
-	case *syscall.SockaddrUnix:
-		if sa.Name != "" {
-			addr = &UnixAddr{Name: sa.Name, Net: sotypeToNet(c.fd.sotype)}
-		}
-	}
-	return
-}
-
-func (c *UnixConn) writeTo(b []byte, addr *UnixAddr) (int, error) {
-	if c.fd.isConnected {
-		return 0, ErrWriteToConnected
-	}
-	if addr == nil {
-		return 0, errMissingAddress
-	}
-	if addr.Net != sotypeToNet(c.fd.sotype) {
-		return 0, syscall.EAFNOSUPPORT
-	}
-	sa := &syscall.SockaddrUnix{Name: addr.Name}
-	return c.fd.writeTo(b, sa)
-}
-
-func (c *UnixConn) writeMsg(b, oob []byte, addr *UnixAddr) (n, oobn int, err error) {
-	if c.fd.sotype == syscall.SOCK_DGRAM && c.fd.isConnected {
-		return 0, 0, ErrWriteToConnected
-	}
-	var sa syscall.Sockaddr
-	if addr != nil {
-		if addr.Net != sotypeToNet(c.fd.sotype) {
-			return 0, 0, syscall.EAFNOSUPPORT
-		}
-		sa = &syscall.SockaddrUnix{Name: addr.Name}
-	}
-	return c.fd.writeMsg(b, oob, sa)
-}
-
-func (sd *sysDialer) dialUnix(ctx context.Context, laddr, raddr *UnixAddr) (*UnixConn, error) {
-	fd, err := unixSocket(ctx, sd.network, laddr, raddr, "dial", sd.Dialer.Control)
-	if err != nil {
-		return nil, err
-	}
-	return newUnixConn(fd), nil
-}
-
-func (ln *UnixListener) accept() (*UnixConn, error) {
-	fd, err := ln.fd.accept()
-	if err != nil {
-		return nil, err
-	}
-	return newUnixConn(fd), nil
-}
-
-func (ln *UnixListener) close() error {
-	// The operating system doesn't clean up
-	// the file that announcing created, so
-	// we have to clean it up ourselves.
-	// There's a race here--we can't know for
-	// sure whether someone else has come along
-	// and replaced our socket name already--
-	// but this sequence (remove then close)
-	// is at least compatible with the auto-remove
-	// sequence in ListenUnix. It's only non-Go
-	// programs that can mess us up.
-	// Even if there are racy calls to Close, we want to unlink only for the first one.
-	ln.unlinkOnce.Do(func() {
-		if ln.path[0] != '@' && ln.unlink {
-			syscall.Unlink(ln.path)
-		}
-	})
-	return ln.fd.Close()
-}
-
-func (ln *UnixListener) file() (*os.File, error) {
-	f, err := ln.fd.dup()
-	if err != nil {
-		return nil, err
-	}
-	return f, nil
-}
-
-// SetUnlinkOnClose sets whether the underlying socket file should be removed
-// from the file system when the listener is closed.
-//
-// The default behavior is to unlink the socket file only when package net created it.
-// That is, when the listener and the underlying socket file were created by a call to
-// Listen or ListenUnix, then by default closing the listener will remove the socket file.
-// but if the listener was created by a call to FileListener to use an already existing
-// socket file, then by default closing the listener will not remove the socket file.
-func (l *UnixListener) SetUnlinkOnClose(unlink bool) {
-	l.unlink = unlink
-}
-
-func (sl *sysListener) listenUnix(ctx context.Context, laddr *UnixAddr) (*UnixListener, error) {
-	fd, err := unixSocket(ctx, sl.network, laddr, nil, "listen", sl.ListenConfig.Control)
-	if err != nil {
-		return nil, err
-	}
-	return &UnixListener{fd: fd, path: fd.laddr.String(), unlink: true}, nil
-}
-
-func (sl *sysListener) listenUnixgram(ctx context.Context, laddr *UnixAddr) (*UnixConn, error) {
-	fd, err := unixSocket(ctx, sl.network, laddr, nil, "listen", sl.ListenConfig.Control)
-	if err != nil {
-		return nil, err
-	}
-	return newUnixConn(fd), nil
-}
diff --git a/contrib/go/_std_1.18/src/net/url/url.go b/contrib/go/_std_1.18/src/net/url/url.go
deleted file mode 100644
index f31aa08b59..0000000000
--- a/contrib/go/_std_1.18/src/net/url/url.go
+++ /dev/null
@@ -1,1218 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package url parses URLs and implements query escaping.
-package url
-
-// See RFC 3986. This package generally follows RFC 3986, except where
-// it deviates for compatibility reasons. When sending changes, first
-// search old issues for history on decisions. Unit tests should also
-// contain references to issue numbers with details.
-
-import (
-	"errors"
-	"fmt"
-	"sort"
-	"strconv"
-	"strings"
-)
-
-// Error reports an error and the operation and URL that caused it.
-type Error struct {
-	Op  string
-	URL string
-	Err error
-}
-
-func (e *Error) Unwrap() error { return e.Err }
-func (e *Error) Error() string { return fmt.Sprintf("%s %q: %s", e.Op, e.URL, e.Err) }
-
-func (e *Error) Timeout() bool {
-	t, ok := e.Err.(interface {
-		Timeout() bool
-	})
-	return ok && t.Timeout()
-}
-
-func (e *Error) Temporary() bool {
-	t, ok := e.Err.(interface {
-		Temporary() bool
-	})
-	return ok && t.Temporary()
-}
-
-const upperhex = "0123456789ABCDEF"
-
-func ishex(c byte) bool {
-	switch {
-	case '0' <= c && c <= '9':
-		return true
-	case 'a' <= c && c <= 'f':
-		return true
-	case 'A' <= c && c <= 'F':
-		return true
-	}
-	return false
-}
-
-func unhex(c byte) byte {
-	switch {
-	case '0' <= c && c <= '9':
-		return c - '0'
-	case 'a' <= c && c <= 'f':
-		return c - 'a' + 10
-	case 'A' <= c && c <= 'F':
-		return c - 'A' + 10
-	}
-	return 0
-}
-
-type encoding int
-
-const (
-	encodePath encoding = 1 + iota
-	encodePathSegment
-	encodeHost
-	encodeZone
-	encodeUserPassword
-	encodeQueryComponent
-	encodeFragment
-)
-
-type EscapeError string
-
-func (e EscapeError) Error() string {
-	return "invalid URL escape " + strconv.Quote(string(e))
-}
-
-type InvalidHostError string
-
-func (e InvalidHostError) Error() string {
-	return "invalid character " + strconv.Quote(string(e)) + " in host name"
-}
-
-// Return true if the specified character should be escaped when
-// appearing in a URL string, according to RFC 3986.
-//
-// Please be informed that for now shouldEscape does not check all
-// reserved characters correctly. See golang.org/issue/5684.
-func shouldEscape(c byte, mode encoding) bool {
-	// §2.3 Unreserved characters (alphanum)
-	if 'a' <= c && c <= 'z' || 'A' <= c && c <= 'Z' || '0' <= c && c <= '9' {
-		return false
-	}
-
-	if mode == encodeHost || mode == encodeZone {
-		// §3.2.2 Host allows
-		//	sub-delims = "!" / "$" / "&" / "'" / "(" / ")" / "*" / "+" / "," / ";" / "="
-		// as part of reg-name.
-		// We add : because we include :port as part of host.
-		// We add [ ] because we include [ipv6]:port as part of host.
-		// We add < > because they're the only characters left that
-		// we could possibly allow, and Parse will reject them if we
-		// escape them (because hosts can't use %-encoding for
-		// ASCII bytes).
-		switch c {
-		case '!', '$', '&', '\'', '(', ')', '*', '+', ',', ';', '=', ':', '[', ']', '<', '>', '"':
-			return false
-		}
-	}
-
-	switch c {
-	case '-', '_', '.', '~': // §2.3 Unreserved characters (mark)
-		return false
-
-	case '$', '&', '+', ',', '/', ':', ';', '=', '?', '@': // §2.2 Reserved characters (reserved)
-		// Different sections of the URL allow a few of
-		// the reserved characters to appear unescaped.
-		switch mode {
-		case encodePath: // §3.3
-			// The RFC allows : @ & = + $ but saves / ; , for assigning
-			// meaning to individual path segments. This package
-			// only manipulates the path as a whole, so we allow those
-			// last three as well. That leaves only ? to escape.
-			return c == '?'
-
-		case encodePathSegment: // §3.3
-			// The RFC allows : @ & = + $ but saves / ; , for assigning
-			// meaning to individual path segments.
-			return c == '/' || c == ';' || c == ',' || c == '?'
-
-		case encodeUserPassword: // §3.2.1
-			// The RFC allows ';', ':', '&', '=', '+', '$', and ',' in
-			// userinfo, so we must escape only '@', '/', and '?'.
-			// The parsing of userinfo treats ':' as special so we must escape
-			// that too.
-			return c == '@' || c == '/' || c == '?' || c == ':'
-
-		case encodeQueryComponent: // §3.4
-			// The RFC reserves (so we must escape) everything.
-			return true
-
-		case encodeFragment: // §4.1
-			// The RFC text is silent but the grammar allows
-			// everything, so escape nothing.
-			return false
-		}
-	}
-
-	if mode == encodeFragment {
-		// RFC 3986 §2.2 allows not escaping sub-delims. A subset of sub-delims are
-		// included in reserved from RFC 2396 §2.2. The remaining sub-delims do not
-		// need to be escaped. To minimize potential breakage, we apply two restrictions:
-		// (1) we always escape sub-delims outside of the fragment, and (2) we always
-		// escape single quote to avoid breaking callers that had previously assumed that
-		// single quotes would be escaped. See issue #19917.
-		switch c {
-		case '!', '(', ')', '*':
-			return false
-		}
-	}
-
-	// Everything else must be escaped.
-	return true
-}
-
-// QueryUnescape does the inverse transformation of QueryEscape,
-// converting each 3-byte encoded substring of the form "%AB" into the
-// hex-decoded byte 0xAB.
-// It returns an error if any % is not followed by two hexadecimal
-// digits.
-func QueryUnescape(s string) (string, error) {
-	return unescape(s, encodeQueryComponent)
-}
-
-// PathUnescape does the inverse transformation of PathEscape,
-// converting each 3-byte encoded substring of the form "%AB" into the
-// hex-decoded byte 0xAB. It returns an error if any % is not followed
-// by two hexadecimal digits.
-//
-// PathUnescape is identical to QueryUnescape except that it does not
-// unescape '+' to ' ' (space).
-func PathUnescape(s string) (string, error) {
-	return unescape(s, encodePathSegment)
-}
-
-// unescape unescapes a string; the mode specifies
-// which section of the URL string is being unescaped.
-func unescape(s string, mode encoding) (string, error) {
-	// Count %, check that they're well-formed.
-	n := 0
-	hasPlus := false
-	for i := 0; i < len(s); {
-		switch s[i] {
-		case '%':
-			n++
-			if i+2 >= len(s) || !ishex(s[i+1]) || !ishex(s[i+2]) {
-				s = s[i:]
-				if len(s) > 3 {
-					s = s[:3]
-				}
-				return "", EscapeError(s)
-			}
-			// Per https://tools.ietf.org/html/rfc3986#page-21
-			// in the host component %-encoding can only be used
-			// for non-ASCII bytes.
-			// But https://tools.ietf.org/html/rfc6874#section-2
-			// introduces %25 being allowed to escape a percent sign
-			// in IPv6 scoped-address literals. Yay.
-			if mode == encodeHost && unhex(s[i+1]) < 8 && s[i:i+3] != "%25" {
-				return "", EscapeError(s[i : i+3])
-			}
-			if mode == encodeZone {
-				// RFC 6874 says basically "anything goes" for zone identifiers
-				// and that even non-ASCII can be redundantly escaped,
-				// but it seems prudent to restrict %-escaped bytes here to those
-				// that are valid host name bytes in their unescaped form.
-				// That is, you can use escaping in the zone identifier but not
-				// to introduce bytes you couldn't just write directly.
-				// But Windows puts spaces here! Yay.
-				v := unhex(s[i+1])<<4 | unhex(s[i+2])
-				if s[i:i+3] != "%25" && v != ' ' && shouldEscape(v, encodeHost) {
-					return "", EscapeError(s[i : i+3])
-				}
-			}
-			i += 3
-		case '+':
-			hasPlus = mode == encodeQueryComponent
-			i++
-		default:
-			if (mode == encodeHost || mode == encodeZone) && s[i] < 0x80 && shouldEscape(s[i], mode) {
-				return "", InvalidHostError(s[i : i+1])
-			}
-			i++
-		}
-	}
-
-	if n == 0 && !hasPlus {
-		return s, nil
-	}
-
-	var t strings.Builder
-	t.Grow(len(s) - 2*n)
-	for i := 0; i < len(s); i++ {
-		switch s[i] {
-		case '%':
-			t.WriteByte(unhex(s[i+1])<<4 | unhex(s[i+2]))
-			i += 2
-		case '+':
-			if mode == encodeQueryComponent {
-				t.WriteByte(' ')
-			} else {
-				t.WriteByte('+')
-			}
-		default:
-			t.WriteByte(s[i])
-		}
-	}
-	return t.String(), nil
-}
-
-// QueryEscape escapes the string so it can be safely placed
-// inside a URL query.
-func QueryEscape(s string) string {
-	return escape(s, encodeQueryComponent)
-}
-
-// PathEscape escapes the string so it can be safely placed inside a URL path segment,
-// replacing special characters (including /) with %XX sequences as needed.
-func PathEscape(s string) string {
-	return escape(s, encodePathSegment)
-}
-
-func escape(s string, mode encoding) string {
-	spaceCount, hexCount := 0, 0
-	for i := 0; i < len(s); i++ {
-		c := s[i]
-		if shouldEscape(c, mode) {
-			if c == ' ' && mode == encodeQueryComponent {
-				spaceCount++
-			} else {
-				hexCount++
-			}
-		}
-	}
-
-	if spaceCount == 0 && hexCount == 0 {
-		return s
-	}
-
-	var buf [64]byte
-	var t []byte
-
-	required := len(s) + 2*hexCount
-	if required <= len(buf) {
-		t = buf[:required]
-	} else {
-		t = make([]byte, required)
-	}
-
-	if hexCount == 0 {
-		copy(t, s)
-		for i := 0; i < len(s); i++ {
-			if s[i] == ' ' {
-				t[i] = '+'
-			}
-		}
-		return string(t)
-	}
-
-	j := 0
-	for i := 0; i < len(s); i++ {
-		switch c := s[i]; {
-		case c == ' ' && mode == encodeQueryComponent:
-			t[j] = '+'
-			j++
-		case shouldEscape(c, mode):
-			t[j] = '%'
-			t[j+1] = upperhex[c>>4]
-			t[j+2] = upperhex[c&15]
-			j += 3
-		default:
-			t[j] = s[i]
-			j++
-		}
-	}
-	return string(t)
-}
-
-// A URL represents a parsed URL (technically, a URI reference).
-//
-// The general form represented is:
-//
-//	[scheme:][//[userinfo@]host][/]path[?query][#fragment]
-//
-// URLs that do not start with a slash after the scheme are interpreted as:
-//
-//	scheme:opaque[?query][#fragment]
-//
-// Note that the Path field is stored in decoded form: /%47%6f%2f becomes /Go/.
-// A consequence is that it is impossible to tell which slashes in the Path were
-// slashes in the raw URL and which were %2f. This distinction is rarely important,
-// but when it is, the code should use RawPath, an optional field which only gets
-// set if the default encoding is different from Path.
-//
-// URL's String method uses the EscapedPath method to obtain the path. See the
-// EscapedPath method for more details.
-type URL struct {
-	Scheme      string
-	Opaque      string    // encoded opaque data
-	User        *Userinfo // username and password information
-	Host        string    // host or host:port
-	Path        string    // path (relative paths may omit leading slash)
-	RawPath     string    // encoded path hint (see EscapedPath method)
-	ForceQuery  bool      // append a query ('?') even if RawQuery is empty
-	RawQuery    string    // encoded query values, without '?'
-	Fragment    string    // fragment for references, without '#'
-	RawFragment string    // encoded fragment hint (see EscapedFragment method)
-}
-
-// User returns a Userinfo containing the provided username
-// and no password set.
-func User(username string) *Userinfo {
-	return &Userinfo{username, "", false}
-}
-
-// UserPassword returns a Userinfo containing the provided username
-// and password.
-//
-// This functionality should only be used with legacy web sites.
-// RFC 2396 warns that interpreting Userinfo this way
-// ``is NOT RECOMMENDED, because the passing of authentication
-// information in clear text (such as URI) has proven to be a
-// security risk in almost every case where it has been used.''
-func UserPassword(username, password string) *Userinfo {
-	return &Userinfo{username, password, true}
-}
-
-// The Userinfo type is an immutable encapsulation of username and
-// password details for a URL. An existing Userinfo value is guaranteed
-// to have a username set (potentially empty, as allowed by RFC 2396),
-// and optionally a password.
-type Userinfo struct {
-	username    string
-	password    string
-	passwordSet bool
-}
-
-// Username returns the username.
-func (u *Userinfo) Username() string {
-	if u == nil {
-		return ""
-	}
-	return u.username
-}
-
-// Password returns the password in case it is set, and whether it is set.
-func (u *Userinfo) Password() (string, bool) {
-	if u == nil {
-		return "", false
-	}
-	return u.password, u.passwordSet
-}
-
-// String returns the encoded userinfo information in the standard form
-// of "username[:password]".
-func (u *Userinfo) String() string {
-	if u == nil {
-		return ""
-	}
-	s := escape(u.username, encodeUserPassword)
-	if u.passwordSet {
-		s += ":" + escape(u.password, encodeUserPassword)
-	}
-	return s
-}
-
-// Maybe rawURL is of the form scheme:path.
-// (Scheme must be [a-zA-Z][a-zA-Z0-9+-.]*)
-// If so, return scheme, path; else return "", rawURL.
-func getScheme(rawURL string) (scheme, path string, err error) {
-	for i := 0; i < len(rawURL); i++ {
-		c := rawURL[i]
-		switch {
-		case 'a' <= c && c <= 'z' || 'A' <= c && c <= 'Z':
-		// do nothing
-		case '0' <= c && c <= '9' || c == '+' || c == '-' || c == '.':
-			if i == 0 {
-				return "", rawURL, nil
-			}
-		case c == ':':
-			if i == 0 {
-				return "", "", errors.New("missing protocol scheme")
-			}
-			return rawURL[:i], rawURL[i+1:], nil
-		default:
-			// we have encountered an invalid character,
-			// so there is no valid scheme
-			return "", rawURL, nil
-		}
-	}
-	return "", rawURL, nil
-}
-
-// Parse parses a raw url into a URL structure.
-//
-// The url may be relative (a path, without a host) or absolute
-// (starting with a scheme). Trying to parse a hostname and path
-// without a scheme is invalid but may not necessarily return an
-// error, due to parsing ambiguities.
-func Parse(rawURL string) (*URL, error) {
-	// Cut off #frag
-	u, frag, _ := strings.Cut(rawURL, "#")
-	url, err := parse(u, false)
-	if err != nil {
-		return nil, &Error{"parse", u, err}
-	}
-	if frag == "" {
-		return url, nil
-	}
-	if err = url.setFragment(frag); err != nil {
-		return nil, &Error{"parse", rawURL, err}
-	}
-	return url, nil
-}
-
-// ParseRequestURI parses a raw url into a URL structure. It assumes that
-// url was received in an HTTP request, so the url is interpreted
-// only as an absolute URI or an absolute path.
-// The string url is assumed not to have a #fragment suffix.
-// (Web browsers strip #fragment before sending the URL to a web server.)
-func ParseRequestURI(rawURL string) (*URL, error) {
-	url, err := parse(rawURL, true)
-	if err != nil {
-		return nil, &Error{"parse", rawURL, err}
-	}
-	return url, nil
-}
-
-// parse parses a URL from a string in one of two contexts. If
-// viaRequest is true, the URL is assumed to have arrived via an HTTP request,
-// in which case only absolute URLs or path-absolute relative URLs are allowed.
-// If viaRequest is false, all forms of relative URLs are allowed.
-func parse(rawURL string, viaRequest bool) (*URL, error) {
-	var rest string
-	var err error
-
-	if stringContainsCTLByte(rawURL) {
-		return nil, errors.New("net/url: invalid control character in URL")
-	}
-
-	if rawURL == "" && viaRequest {
-		return nil, errors.New("empty url")
-	}
-	url := new(URL)
-
-	if rawURL == "*" {
-		url.Path = "*"
-		return url, nil
-	}
-
-	// Split off possible leading "http:", "mailto:", etc.
-	// Cannot contain escaped characters.
-	if url.Scheme, rest, err = getScheme(rawURL); err != nil {
-		return nil, err
-	}
-	url.Scheme = strings.ToLower(url.Scheme)
-
-	if strings.HasSuffix(rest, "?") && strings.Count(rest, "?") == 1 {
-		url.ForceQuery = true
-		rest = rest[:len(rest)-1]
-	} else {
-		rest, url.RawQuery, _ = strings.Cut(rest, "?")
-	}
-
-	if !strings.HasPrefix(rest, "/") {
-		if url.Scheme != "" {
-			// We consider rootless paths per RFC 3986 as opaque.
-			url.Opaque = rest
-			return url, nil
-		}
-		if viaRequest {
-			return nil, errors.New("invalid URI for request")
-		}
-
-		// Avoid confusion with malformed schemes, like cache_object:foo/bar.
-		// See golang.org/issue/16822.
-		//
-		// RFC 3986, §3.3:
-		// In addition, a URI reference (Section 4.1) may be a relative-path reference,
-		// in which case the first path segment cannot contain a colon (":") character.
-		if segment, _, _ := strings.Cut(rest, "/"); strings.Contains(segment, ":") {
-			// First path segment has colon. Not allowed in relative URL.
-			return nil, errors.New("first path segment in URL cannot contain colon")
-		}
-	}
-
-	if (url.Scheme != "" || !viaRequest && !strings.HasPrefix(rest, "///")) && strings.HasPrefix(rest, "//") {
-		var authority string
-		authority, rest = rest[2:], ""
-		if i := strings.Index(authority, "/"); i >= 0 {
-			authority, rest = authority[:i], authority[i:]
-		}
-		url.User, url.Host, err = parseAuthority(authority)
-		if err != nil {
-			return nil, err
-		}
-	}
-	// Set Path and, optionally, RawPath.
-	// RawPath is a hint of the encoding of Path. We don't want to set it if
-	// the default escaping of Path is equivalent, to help make sure that people
-	// don't rely on it in general.
-	if err := url.setPath(rest); err != nil {
-		return nil, err
-	}
-	return url, nil
-}
-
-func parseAuthority(authority string) (user *Userinfo, host string, err error) {
-	i := strings.LastIndex(authority, "@")
-	if i < 0 {
-		host, err = parseHost(authority)
-	} else {
-		host, err = parseHost(authority[i+1:])
-	}
-	if err != nil {
-		return nil, "", err
-	}
-	if i < 0 {
-		return nil, host, nil
-	}
-	userinfo := authority[:i]
-	if !validUserinfo(userinfo) {
-		return nil, "", errors.New("net/url: invalid userinfo")
-	}
-	if !strings.Contains(userinfo, ":") {
-		if userinfo, err = unescape(userinfo, encodeUserPassword); err != nil {
-			return nil, "", err
-		}
-		user = User(userinfo)
-	} else {
-		username, password, _ := strings.Cut(userinfo, ":")
-		if username, err = unescape(username, encodeUserPassword); err != nil {
-			return nil, "", err
-		}
-		if password, err = unescape(password, encodeUserPassword); err != nil {
-			return nil, "", err
-		}
-		user = UserPassword(username, password)
-	}
-	return user, host, nil
-}
-
-// parseHost parses host as an authority without user
-// information. That is, as host[:port].
-func parseHost(host string) (string, error) {
-	if strings.HasPrefix(host, "[") {
-		// Parse an IP-Literal in RFC 3986 and RFC 6874.
-		// E.g., "[fe80::1]", "[fe80::1%25en0]", "[fe80::1]:80".
-		i := strings.LastIndex(host, "]")
-		if i < 0 {
-			return "", errors.New("missing ']' in host")
-		}
-		colonPort := host[i+1:]
-		if !validOptionalPort(colonPort) {
-			return "", fmt.Errorf("invalid port %q after host", colonPort)
-		}
-
-		// RFC 6874 defines that %25 (%-encoded percent) introduces
-		// the zone identifier, and the zone identifier can use basically
-		// any %-encoding it likes. That's different from the host, which
-		// can only %-encode non-ASCII bytes.
-		// We do impose some restrictions on the zone, to avoid stupidity
-		// like newlines.
-		zone := strings.Index(host[:i], "%25")
-		if zone >= 0 {
-			host1, err := unescape(host[:zone], encodeHost)
-			if err != nil {
-				return "", err
-			}
-			host2, err := unescape(host[zone:i], encodeZone)
-			if err != nil {
-				return "", err
-			}
-			host3, err := unescape(host[i:], encodeHost)
-			if err != nil {
-				return "", err
-			}
-			return host1 + host2 + host3, nil
-		}
-	} else if i := strings.LastIndex(host, ":"); i != -1 {
-		colonPort := host[i:]
-		if !validOptionalPort(colonPort) {
-			return "", fmt.Errorf("invalid port %q after host", colonPort)
-		}
-	}
-
-	var err error
-	if host, err = unescape(host, encodeHost); err != nil {
-		return "", err
-	}
-	return host, nil
-}
-
-// setPath sets the Path and RawPath fields of the URL based on the provided
-// escaped path p. It maintains the invariant that RawPath is only specified
-// when it differs from the default encoding of the path.
-// For example:
-// - setPath("/foo/bar")   will set Path="/foo/bar" and RawPath=""
-// - setPath("/foo%2fbar") will set Path="/foo/bar" and RawPath="/foo%2fbar"
-// setPath will return an error only if the provided path contains an invalid
-// escaping.
-func (u *URL) setPath(p string) error {
-	path, err := unescape(p, encodePath)
-	if err != nil {
-		return err
-	}
-	u.Path = path
-	if escp := escape(path, encodePath); p == escp {
-		// Default encoding is fine.
-		u.RawPath = ""
-	} else {
-		u.RawPath = p
-	}
-	return nil
-}
-
-// EscapedPath returns the escaped form of u.Path.
-// In general there are multiple possible escaped forms of any path.
-// EscapedPath returns u.RawPath when it is a valid escaping of u.Path.
-// Otherwise EscapedPath ignores u.RawPath and computes an escaped
-// form on its own.
-// The String and RequestURI methods use EscapedPath to construct
-// their results.
-// In general, code should call EscapedPath instead of
-// reading u.RawPath directly.
-func (u *URL) EscapedPath() string {
-	if u.RawPath != "" && validEncoded(u.RawPath, encodePath) {
-		p, err := unescape(u.RawPath, encodePath)
-		if err == nil && p == u.Path {
-			return u.RawPath
-		}
-	}
-	if u.Path == "*" {
-		return "*" // don't escape (Issue 11202)
-	}
-	return escape(u.Path, encodePath)
-}
-
-// validEncoded reports whether s is a valid encoded path or fragment,
-// according to mode.
-// It must not contain any bytes that require escaping during encoding.
-func validEncoded(s string, mode encoding) bool {
-	for i := 0; i < len(s); i++ {
-		// RFC 3986, Appendix A.
-		// pchar = unreserved / pct-encoded / sub-delims / ":" / "@".
-		// shouldEscape is not quite compliant with the RFC,
-		// so we check the sub-delims ourselves and let
-		// shouldEscape handle the others.
-		switch s[i] {
-		case '!', '$', '&', '\'', '(', ')', '*', '+', ',', ';', '=', ':', '@':
-			// ok
-		case '[', ']':
-			// ok - not specified in RFC 3986 but left alone by modern browsers
-		case '%':
-			// ok - percent encoded, will decode
-		default:
-			if shouldEscape(s[i], mode) {
-				return false
-			}
-		}
-	}
-	return true
-}
-
-// setFragment is like setPath but for Fragment/RawFragment.
-func (u *URL) setFragment(f string) error {
-	frag, err := unescape(f, encodeFragment)
-	if err != nil {
-		return err
-	}
-	u.Fragment = frag
-	if escf := escape(frag, encodeFragment); f == escf {
-		// Default encoding is fine.
-		u.RawFragment = ""
-	} else {
-		u.RawFragment = f
-	}
-	return nil
-}
-
-// EscapedFragment returns the escaped form of u.Fragment.
-// In general there are multiple possible escaped forms of any fragment.
-// EscapedFragment returns u.RawFragment when it is a valid escaping of u.Fragment.
-// Otherwise EscapedFragment ignores u.RawFragment and computes an escaped
-// form on its own.
-// The String method uses EscapedFragment to construct its result.
-// In general, code should call EscapedFragment instead of
-// reading u.RawFragment directly.
-func (u *URL) EscapedFragment() string {
-	if u.RawFragment != "" && validEncoded(u.RawFragment, encodeFragment) {
-		f, err := unescape(u.RawFragment, encodeFragment)
-		if err == nil && f == u.Fragment {
-			return u.RawFragment
-		}
-	}
-	return escape(u.Fragment, encodeFragment)
-}
-
-// validOptionalPort reports whether port is either an empty string
-// or matches /^:\d*$/
-func validOptionalPort(port string) bool {
-	if port == "" {
-		return true
-	}
-	if port[0] != ':' {
-		return false
-	}
-	for _, b := range port[1:] {
-		if b < '0' || b > '9' {
-			return false
-		}
-	}
-	return true
-}
-
-// String reassembles the URL into a valid URL string.
-// The general form of the result is one of:
-//
-//	scheme:opaque?query#fragment
-//	scheme://userinfo@host/path?query#fragment
-//
-// If u.Opaque is non-empty, String uses the first form;
-// otherwise it uses the second form.
-// Any non-ASCII characters in host are escaped.
-// To obtain the path, String uses u.EscapedPath().
-//
-// In the second form, the following rules apply:
-//	- if u.Scheme is empty, scheme: is omitted.
-//	- if u.User is nil, userinfo@ is omitted.
-//	- if u.Host is empty, host/ is omitted.
-//	- if u.Scheme and u.Host are empty and u.User is nil,
-//	   the entire scheme://userinfo@host/ is omitted.
-//	- if u.Host is non-empty and u.Path begins with a /,
-//	   the form host/path does not add its own /.
-//	- if u.RawQuery is empty, ?query is omitted.
-//	- if u.Fragment is empty, #fragment is omitted.
-func (u *URL) String() string {
-	var buf strings.Builder
-	if u.Scheme != "" {
-		buf.WriteString(u.Scheme)
-		buf.WriteByte(':')
-	}
-	if u.Opaque != "" {
-		buf.WriteString(u.Opaque)
-	} else {
-		if u.Scheme != "" || u.Host != "" || u.User != nil {
-			if u.Host != "" || u.Path != "" || u.User != nil {
-				buf.WriteString("//")
-			}
-			if ui := u.User; ui != nil {
-				buf.WriteString(ui.String())
-				buf.WriteByte('@')
-			}
-			if h := u.Host; h != "" {
-				buf.WriteString(escape(h, encodeHost))
-			}
-		}
-		path := u.EscapedPath()
-		if path != "" && path[0] != '/' && u.Host != "" {
-			buf.WriteByte('/')
-		}
-		if buf.Len() == 0 {
-			// RFC 3986 §4.2
-			// A path segment that contains a colon character (e.g., "this:that")
-			// cannot be used as the first segment of a relative-path reference, as
-			// it would be mistaken for a scheme name. Such a segment must be
-			// preceded by a dot-segment (e.g., "./this:that") to make a relative-
-			// path reference.
-			if segment, _, _ := strings.Cut(path, "/"); strings.Contains(segment, ":") {
-				buf.WriteString("./")
-			}
-		}
-		buf.WriteString(path)
-	}
-	if u.ForceQuery || u.RawQuery != "" {
-		buf.WriteByte('?')
-		buf.WriteString(u.RawQuery)
-	}
-	if u.Fragment != "" {
-		buf.WriteByte('#')
-		buf.WriteString(u.EscapedFragment())
-	}
-	return buf.String()
-}
-
-// Redacted is like String but replaces any password with "xxxxx".
-// Only the password in u.URL is redacted.
-func (u *URL) Redacted() string {
-	if u == nil {
-		return ""
-	}
-
-	ru := *u
-	if _, has := ru.User.Password(); has {
-		ru.User = UserPassword(ru.User.Username(), "xxxxx")
-	}
-	return ru.String()
-}
-
-// Values maps a string key to a list of values.
-// It is typically used for query parameters and form values.
-// Unlike in the http.Header map, the keys in a Values map
-// are case-sensitive.
-type Values map[string][]string
-
-// Get gets the first value associated with the given key.
-// If there are no values associated with the key, Get returns
-// the empty string. To access multiple values, use the map
-// directly.
-func (v Values) Get(key string) string {
-	if v == nil {
-		return ""
-	}
-	vs := v[key]
-	if len(vs) == 0 {
-		return ""
-	}
-	return vs[0]
-}
-
-// Set sets the key to value. It replaces any existing
-// values.
-func (v Values) Set(key, value string) {
-	v[key] = []string{value}
-}
-
-// Add adds the value to key. It appends to any existing
-// values associated with key.
-func (v Values) Add(key, value string) {
-	v[key] = append(v[key], value)
-}
-
-// Del deletes the values associated with key.
-func (v Values) Del(key string) {
-	delete(v, key)
-}
-
-// Has checks whether a given key is set.
-func (v Values) Has(key string) bool {
-	_, ok := v[key]
-	return ok
-}
-
-// ParseQuery parses the URL-encoded query string and returns
-// a map listing the values specified for each key.
-// ParseQuery always returns a non-nil map containing all the
-// valid query parameters found; err describes the first decoding error
-// encountered, if any.
-//
-// Query is expected to be a list of key=value settings separated by ampersands.
-// A setting without an equals sign is interpreted as a key set to an empty
-// value.
-// Settings containing a non-URL-encoded semicolon are considered invalid.
-func ParseQuery(query string) (Values, error) {
-	m := make(Values)
-	err := parseQuery(m, query)
-	return m, err
-}
-
-func parseQuery(m Values, query string) (err error) {
-	for query != "" {
-		var key string
-		key, query, _ = strings.Cut(query, "&")
-		if strings.Contains(key, ";") {
-			err = fmt.Errorf("invalid semicolon separator in query")
-			continue
-		}
-		if key == "" {
-			continue
-		}
-		key, value, _ := strings.Cut(key, "=")
-		key, err1 := QueryUnescape(key)
-		if err1 != nil {
-			if err == nil {
-				err = err1
-			}
-			continue
-		}
-		value, err1 = QueryUnescape(value)
-		if err1 != nil {
-			if err == nil {
-				err = err1
-			}
-			continue
-		}
-		m[key] = append(m[key], value)
-	}
-	return err
-}
-
-// Encode encodes the values into ``URL encoded'' form
-// ("bar=baz&foo=quux") sorted by key.
-func (v Values) Encode() string {
-	if v == nil {
-		return ""
-	}
-	var buf strings.Builder
-	keys := make([]string, 0, len(v))
-	for k := range v {
-		keys = append(keys, k)
-	}
-	sort.Strings(keys)
-	for _, k := range keys {
-		vs := v[k]
-		keyEscaped := QueryEscape(k)
-		for _, v := range vs {
-			if buf.Len() > 0 {
-				buf.WriteByte('&')
-			}
-			buf.WriteString(keyEscaped)
-			buf.WriteByte('=')
-			buf.WriteString(QueryEscape(v))
-		}
-	}
-	return buf.String()
-}
-
-// resolvePath applies special path segments from refs and applies
-// them to base, per RFC 3986.
-func resolvePath(base, ref string) string {
-	var full string
-	if ref == "" {
-		full = base
-	} else if ref[0] != '/' {
-		i := strings.LastIndex(base, "/")
-		full = base[:i+1] + ref
-	} else {
-		full = ref
-	}
-	if full == "" {
-		return ""
-	}
-
-	var (
-		elem string
-		dst  strings.Builder
-	)
-	first := true
-	remaining := full
-	// We want to return a leading '/', so write it now.
-	dst.WriteByte('/')
-	found := true
-	for found {
-		elem, remaining, found = strings.Cut(remaining, "/")
-		if elem == "." {
-			first = false
-			// drop
-			continue
-		}
-
-		if elem == ".." {
-			// Ignore the leading '/' we already wrote.
-			str := dst.String()[1:]
-			index := strings.LastIndexByte(str, '/')
-
-			dst.Reset()
-			dst.WriteByte('/')
-			if index == -1 {
-				first = true
-			} else {
-				dst.WriteString(str[:index])
-			}
-		} else {
-			if !first {
-				dst.WriteByte('/')
-			}
-			dst.WriteString(elem)
-			first = false
-		}
-	}
-
-	if elem == "." || elem == ".." {
-		dst.WriteByte('/')
-	}
-
-	// We wrote an initial '/', but we don't want two.
-	r := dst.String()
-	if len(r) > 1 && r[1] == '/' {
-		r = r[1:]
-	}
-	return r
-}
-
-// IsAbs reports whether the URL is absolute.
-// Absolute means that it has a non-empty scheme.
-func (u *URL) IsAbs() bool {
-	return u.Scheme != ""
-}
-
-// Parse parses a URL in the context of the receiver. The provided URL
-// may be relative or absolute. Parse returns nil, err on parse
-// failure, otherwise its return value is the same as ResolveReference.
-func (u *URL) Parse(ref string) (*URL, error) {
-	refURL, err := Parse(ref)
-	if err != nil {
-		return nil, err
-	}
-	return u.ResolveReference(refURL), nil
-}
-
-// ResolveReference resolves a URI reference to an absolute URI from
-// an absolute base URI u, per RFC 3986 Section 5.2. The URI reference
-// may be relative or absolute. ResolveReference always returns a new
-// URL instance, even if the returned URL is identical to either the
-// base or reference. If ref is an absolute URL, then ResolveReference
-// ignores base and returns a copy of ref.
-func (u *URL) ResolveReference(ref *URL) *URL {
-	url := *ref
-	if ref.Scheme == "" {
-		url.Scheme = u.Scheme
-	}
-	if ref.Scheme != "" || ref.Host != "" || ref.User != nil {
-		// The "absoluteURI" or "net_path" cases.
-		// We can ignore the error from setPath since we know we provided a
-		// validly-escaped path.
-		url.setPath(resolvePath(ref.EscapedPath(), ""))
-		return &url
-	}
-	if ref.Opaque != "" {
-		url.User = nil
-		url.Host = ""
-		url.Path = ""
-		return &url
-	}
-	if ref.Path == "" && !ref.ForceQuery && ref.RawQuery == "" {
-		url.RawQuery = u.RawQuery
-		if ref.Fragment == "" {
-			url.Fragment = u.Fragment
-			url.RawFragment = u.RawFragment
-		}
-	}
-	// The "abs_path" or "rel_path" cases.
-	url.Host = u.Host
-	url.User = u.User
-	url.setPath(resolvePath(u.EscapedPath(), ref.EscapedPath()))
-	return &url
-}
-
-// Query parses RawQuery and returns the corresponding values.
-// It silently discards malformed value pairs.
-// To check errors use ParseQuery.
-func (u *URL) Query() Values {
-	v, _ := ParseQuery(u.RawQuery)
-	return v
-}
-
-// RequestURI returns the encoded path?query or opaque?query
-// string that would be used in an HTTP request for u.
-func (u *URL) RequestURI() string {
-	result := u.Opaque
-	if result == "" {
-		result = u.EscapedPath()
-		if result == "" {
-			result = "/"
-		}
-	} else {
-		if strings.HasPrefix(result, "//") {
-			result = u.Scheme + ":" + result
-		}
-	}
-	if u.ForceQuery || u.RawQuery != "" {
-		result += "?" + u.RawQuery
-	}
-	return result
-}
-
-// Hostname returns u.Host, stripping any valid port number if present.
-//
-// If the result is enclosed in square brackets, as literal IPv6 addresses are,
-// the square brackets are removed from the result.
-func (u *URL) Hostname() string {
-	host, _ := splitHostPort(u.Host)
-	return host
-}
-
-// Port returns the port part of u.Host, without the leading colon.
-//
-// If u.Host doesn't contain a valid numeric port, Port returns an empty string.
-func (u *URL) Port() string {
-	_, port := splitHostPort(u.Host)
-	return port
-}
-
-// splitHostPort separates host and port. If the port is not valid, it returns
-// the entire input as host, and it doesn't check the validity of the host.
-// Unlike net.SplitHostPort, but per RFC 3986, it requires ports to be numeric.
-func splitHostPort(hostPort string) (host, port string) {
-	host = hostPort
-
-	colon := strings.LastIndexByte(host, ':')
-	if colon != -1 && validOptionalPort(host[colon:]) {
-		host, port = host[:colon], host[colon+1:]
-	}
-
-	if strings.HasPrefix(host, "[") && strings.HasSuffix(host, "]") {
-		host = host[1 : len(host)-1]
-	}
-
-	return
-}
-
-// Marshaling interface implementations.
-// Would like to implement MarshalText/UnmarshalText but that will change the JSON representation of URLs.
-
-func (u *URL) MarshalBinary() (text []byte, err error) {
-	return []byte(u.String()), nil
-}
-
-func (u *URL) UnmarshalBinary(text []byte) error {
-	u1, err := Parse(string(text))
-	if err != nil {
-		return err
-	}
-	*u = *u1
-	return nil
-}
-
-// validUserinfo reports whether s is a valid userinfo string per RFC 3986
-// Section 3.2.1:
-//     userinfo    = *( unreserved / pct-encoded / sub-delims / ":" )
-//     unreserved  = ALPHA / DIGIT / "-" / "." / "_" / "~"
-//     sub-delims  = "!" / "$" / "&" / "'" / "(" / ")"
-//                   / "*" / "+" / "," / ";" / "="
-//
-// It doesn't validate pct-encoded. The caller does that via func unescape.
-func validUserinfo(s string) bool {
-	for _, r := range s {
-		if 'A' <= r && r <= 'Z' {
-			continue
-		}
-		if 'a' <= r && r <= 'z' {
-			continue
-		}
-		if '0' <= r && r <= '9' {
-			continue
-		}
-		switch r {
-		case '-', '.', '_', ':', '~', '!', '$', '&', '\'',
-			'(', ')', '*', '+', ',', ';', '=', '%', '@':
-			continue
-		default:
-			return false
-		}
-	}
-	return true
-}
-
-// stringContainsCTLByte reports whether s contains any ASCII control character.
-func stringContainsCTLByte(s string) bool {
-	for i := 0; i < len(s); i++ {
-		b := s[i]
-		if b < ' ' || b == 0x7f {
-			return true
-		}
-	}
-	return false
-}
diff --git a/contrib/go/_std_1.18/src/os/endian_little.go b/contrib/go/_std_1.18/src/os/endian_little.go
deleted file mode 100644
index 10643a804e..0000000000
--- a/contrib/go/_std_1.18/src/os/endian_little.go
+++ /dev/null
@@ -1,9 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-//
-//go:build 386 || amd64 || arm || arm64 || ppc64le || mips64le || mipsle || riscv64 || wasm
-
-package os
-
-const isBigEndian = false
diff --git a/contrib/go/_std_1.18/src/os/error_posix.go b/contrib/go/_std_1.18/src/os/error_posix.go
deleted file mode 100644
index 234f4eb692..0000000000
--- a/contrib/go/_std_1.18/src/os/error_posix.go
+++ /dev/null
@@ -1,18 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris || windows
-
-package os
-
-import "syscall"
-
-// wrapSyscallError takes an error and a syscall name. If the error is
-// a syscall.Errno, it wraps it in a os.SyscallError using the syscall name.
-func wrapSyscallError(name string, err error) error {
-	if _, ok := err.(syscall.Errno); ok {
-		err = NewSyscallError(name, err)
-	}
-	return err
-}
diff --git a/contrib/go/_std_1.18/src/os/exec_posix.go b/contrib/go/_std_1.18/src/os/exec_posix.go
deleted file mode 100644
index d619984693..0000000000
--- a/contrib/go/_std_1.18/src/os/exec_posix.go
+++ /dev/null
@@ -1,136 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris || windows
-
-package os
-
-import (
-	"internal/itoa"
-	"internal/syscall/execenv"
-	"runtime"
-	"syscall"
-)
-
-// The only signal values guaranteed to be present in the os package on all
-// systems are os.Interrupt (send the process an interrupt) and os.Kill (force
-// the process to exit). On Windows, sending os.Interrupt to a process with
-// os.Process.Signal is not implemented; it will return an error instead of
-// sending a signal.
-var (
-	Interrupt Signal = syscall.SIGINT
-	Kill      Signal = syscall.SIGKILL
-)
-
-func startProcess(name string, argv []string, attr *ProcAttr) (p *Process, err error) {
-	// If there is no SysProcAttr (ie. no Chroot or changed
-	// UID/GID), double-check existence of the directory we want
-	// to chdir into. We can make the error clearer this way.
-	if attr != nil && attr.Sys == nil && attr.Dir != "" {
-		if _, err := Stat(attr.Dir); err != nil {
-			pe := err.(*PathError)
-			pe.Op = "chdir"
-			return nil, pe
-		}
-	}
-
-	sysattr := &syscall.ProcAttr{
-		Dir: attr.Dir,
-		Env: attr.Env,
-		Sys: attr.Sys,
-	}
-	if sysattr.Env == nil {
-		sysattr.Env, err = execenv.Default(sysattr.Sys)
-		if err != nil {
-			return nil, err
-		}
-	}
-	sysattr.Files = make([]uintptr, 0, len(attr.Files))
-	for _, f := range attr.Files {
-		sysattr.Files = append(sysattr.Files, f.Fd())
-	}
-
-	pid, h, e := syscall.StartProcess(name, argv, sysattr)
-
-	// Make sure we don't run the finalizers of attr.Files.
-	runtime.KeepAlive(attr)
-
-	if e != nil {
-		return nil, &PathError{Op: "fork/exec", Path: name, Err: e}
-	}
-
-	return newProcess(pid, h), nil
-}
-
-func (p *Process) kill() error {
-	return p.Signal(Kill)
-}
-
-// ProcessState stores information about a process, as reported by Wait.
-type ProcessState struct {
-	pid    int                // The process's id.
-	status syscall.WaitStatus // System-dependent status info.
-	rusage *syscall.Rusage
-}
-
-// Pid returns the process id of the exited process.
-func (p *ProcessState) Pid() int {
-	return p.pid
-}
-
-func (p *ProcessState) exited() bool {
-	return p.status.Exited()
-}
-
-func (p *ProcessState) success() bool {
-	return p.status.ExitStatus() == 0
-}
-
-func (p *ProcessState) sys() any {
-	return p.status
-}
-
-func (p *ProcessState) sysUsage() any {
-	return p.rusage
-}
-
-func (p *ProcessState) String() string {
-	if p == nil {
-		return "<nil>"
-	}
-	status := p.Sys().(syscall.WaitStatus)
-	res := ""
-	switch {
-	case status.Exited():
-		code := status.ExitStatus()
-		if runtime.GOOS == "windows" && uint(code) >= 1<<16 { // windows uses large hex numbers
-			res = "exit status " + uitox(uint(code))
-		} else { // unix systems use small decimal integers
-			res = "exit status " + itoa.Itoa(code) // unix
-		}
-	case status.Signaled():
-		res = "signal: " + status.Signal().String()
-	case status.Stopped():
-		res = "stop signal: " + status.StopSignal().String()
-		if status.StopSignal() == syscall.SIGTRAP && status.TrapCause() != 0 {
-			res += " (trap " + itoa.Itoa(status.TrapCause()) + ")"
-		}
-	case status.Continued():
-		res = "continued"
-	}
-	if status.CoreDump() {
-		res += " (core dumped)"
-	}
-	return res
-}
-
-// ExitCode returns the exit code of the exited process, or -1
-// if the process hasn't exited or was terminated by a signal.
-func (p *ProcessState) ExitCode() int {
-	// return -1 if the process hasn't started.
-	if p == nil {
-		return -1
-	}
-	return p.status.ExitStatus()
-}
diff --git a/contrib/go/_std_1.18/src/os/exec_unix.go b/contrib/go/_std_1.18/src/os/exec_unix.go
deleted file mode 100644
index 250c5c6402..0000000000
--- a/contrib/go/_std_1.18/src/os/exec_unix.go
+++ /dev/null
@@ -1,106 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris
-
-package os
-
-import (
-	"errors"
-	"runtime"
-	"syscall"
-	"time"
-)
-
-func (p *Process) wait() (ps *ProcessState, err error) {
-	if p.Pid == -1 {
-		return nil, syscall.EINVAL
-	}
-
-	// If we can block until Wait4 will succeed immediately, do so.
-	ready, err := p.blockUntilWaitable()
-	if err != nil {
-		return nil, err
-	}
-	if ready {
-		// Mark the process done now, before the call to Wait4,
-		// so that Process.signal will not send a signal.
-		p.setDone()
-		// Acquire a write lock on sigMu to wait for any
-		// active call to the signal method to complete.
-		p.sigMu.Lock()
-		p.sigMu.Unlock()
-	}
-
-	var (
-		status syscall.WaitStatus
-		rusage syscall.Rusage
-		pid1   int
-		e      error
-	)
-	for {
-		pid1, e = syscall.Wait4(p.Pid, &status, 0, &rusage)
-		if e != syscall.EINTR {
-			break
-		}
-	}
-	if e != nil {
-		return nil, NewSyscallError("wait", e)
-	}
-	if pid1 != 0 {
-		p.setDone()
-	}
-	ps = &ProcessState{
-		pid:    pid1,
-		status: status,
-		rusage: &rusage,
-	}
-	return ps, nil
-}
-
-func (p *Process) signal(sig Signal) error {
-	if p.Pid == -1 {
-		return errors.New("os: process already released")
-	}
-	if p.Pid == 0 {
-		return errors.New("os: process not initialized")
-	}
-	p.sigMu.RLock()
-	defer p.sigMu.RUnlock()
-	if p.done() {
-		return ErrProcessDone
-	}
-	s, ok := sig.(syscall.Signal)
-	if !ok {
-		return errors.New("os: unsupported signal type")
-	}
-	if e := syscall.Kill(p.Pid, s); e != nil {
-		if e == syscall.ESRCH {
-			return ErrProcessDone
-		}
-		return e
-	}
-	return nil
-}
-
-func (p *Process) release() error {
-	// NOOP for unix.
-	p.Pid = -1
-	// no need for a finalizer anymore
-	runtime.SetFinalizer(p, nil)
-	return nil
-}
-
-func findProcess(pid int) (p *Process, err error) {
-	// NOOP for unix.
-	return newProcess(pid, 0), nil
-}
-
-func (p *ProcessState) userTime() time.Duration {
-	return time.Duration(p.rusage.Utime.Nano()) * time.Nanosecond
-}
-
-func (p *ProcessState) systemTime() time.Duration {
-	return time.Duration(p.rusage.Stime.Nano()) * time.Nanosecond
-}
diff --git a/contrib/go/_std_1.18/src/os/file.go b/contrib/go/_std_1.18/src/os/file.go
deleted file mode 100644
index 2823128554..0000000000
--- a/contrib/go/_std_1.18/src/os/file.go
+++ /dev/null
@@ -1,723 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package os provides a platform-independent interface to operating system
-// functionality. The design is Unix-like, although the error handling is
-// Go-like; failing calls return values of type error rather than error numbers.
-// Often, more information is available within the error. For example,
-// if a call that takes a file name fails, such as Open or Stat, the error
-// will include the failing file name when printed and will be of type
-// *PathError, which may be unpacked for more information.
-//
-// The os interface is intended to be uniform across all operating systems.
-// Features not generally available appear in the system-specific package syscall.
-//
-// Here is a simple example, opening a file and reading some of it.
-//
-//	file, err := os.Open("file.go") // For read access.
-//	if err != nil {
-//		log.Fatal(err)
-//	}
-//
-// If the open fails, the error string will be self-explanatory, like
-//
-//	open file.go: no such file or directory
-//
-// The file's data can then be read into a slice of bytes. Read and
-// Write take their byte counts from the length of the argument slice.
-//
-//	data := make([]byte, 100)
-//	count, err := file.Read(data)
-//	if err != nil {
-//		log.Fatal(err)
-//	}
-//	fmt.Printf("read %d bytes: %q\n", count, data[:count])
-//
-// Note: The maximum number of concurrent operations on a File may be limited by
-// the OS or the system. The number should be high, but exceeding it may degrade
-// performance or cause other issues.
-//
-package os
-
-import (
-	"errors"
-	"internal/poll"
-	"internal/testlog"
-	"internal/unsafeheader"
-	"io"
-	"io/fs"
-	"runtime"
-	"syscall"
-	"time"
-	"unsafe"
-)
-
-// Name returns the name of the file as presented to Open.
-func (f *File) Name() string { return f.name }
-
-// Stdin, Stdout, and Stderr are open Files pointing to the standard input,
-// standard output, and standard error file descriptors.
-//
-// Note that the Go runtime writes to standard error for panics and crashes;
-// closing Stderr may cause those messages to go elsewhere, perhaps
-// to a file opened later.
-var (
-	Stdin  = NewFile(uintptr(syscall.Stdin), "/dev/stdin")
-	Stdout = NewFile(uintptr(syscall.Stdout), "/dev/stdout")
-	Stderr = NewFile(uintptr(syscall.Stderr), "/dev/stderr")
-)
-
-// Flags to OpenFile wrapping those of the underlying system. Not all
-// flags may be implemented on a given system.
-const (
-	// Exactly one of O_RDONLY, O_WRONLY, or O_RDWR must be specified.
-	O_RDONLY int = syscall.O_RDONLY // open the file read-only.
-	O_WRONLY int = syscall.O_WRONLY // open the file write-only.
-	O_RDWR   int = syscall.O_RDWR   // open the file read-write.
-	// The remaining values may be or'ed in to control behavior.
-	O_APPEND int = syscall.O_APPEND // append data to the file when writing.
-	O_CREATE int = syscall.O_CREAT  // create a new file if none exists.
-	O_EXCL   int = syscall.O_EXCL   // used with O_CREATE, file must not exist.
-	O_SYNC   int = syscall.O_SYNC   // open for synchronous I/O.
-	O_TRUNC  int = syscall.O_TRUNC  // truncate regular writable file when opened.
-)
-
-// Seek whence values.
-//
-// Deprecated: Use io.SeekStart, io.SeekCurrent, and io.SeekEnd.
-const (
-	SEEK_SET int = 0 // seek relative to the origin of the file
-	SEEK_CUR int = 1 // seek relative to the current offset
-	SEEK_END int = 2 // seek relative to the end
-)
-
-// LinkError records an error during a link or symlink or rename
-// system call and the paths that caused it.
-type LinkError struct {
-	Op  string
-	Old string
-	New string
-	Err error
-}
-
-func (e *LinkError) Error() string {
-	return e.Op + " " + e.Old + " " + e.New + ": " + e.Err.Error()
-}
-
-func (e *LinkError) Unwrap() error {
-	return e.Err
-}
-
-// Read reads up to len(b) bytes from the File and stores them in b.
-// It returns the number of bytes read and any error encountered.
-// At end of file, Read returns 0, io.EOF.
-func (f *File) Read(b []byte) (n int, err error) {
-	if err := f.checkValid("read"); err != nil {
-		return 0, err
-	}
-	n, e := f.read(b)
-	return n, f.wrapErr("read", e)
-}
-
-// ReadAt reads len(b) bytes from the File starting at byte offset off.
-// It returns the number of bytes read and the error, if any.
-// ReadAt always returns a non-nil error when n < len(b).
-// At end of file, that error is io.EOF.
-func (f *File) ReadAt(b []byte, off int64) (n int, err error) {
-	if err := f.checkValid("read"); err != nil {
-		return 0, err
-	}
-
-	if off < 0 {
-		return 0, &PathError{Op: "readat", Path: f.name, Err: errors.New("negative offset")}
-	}
-
-	for len(b) > 0 {
-		m, e := f.pread(b, off)
-		if e != nil {
-			err = f.wrapErr("read", e)
-			break
-		}
-		n += m
-		b = b[m:]
-		off += int64(m)
-	}
-	return
-}
-
-// ReadFrom implements io.ReaderFrom.
-func (f *File) ReadFrom(r io.Reader) (n int64, err error) {
-	if err := f.checkValid("write"); err != nil {
-		return 0, err
-	}
-	n, handled, e := f.readFrom(r)
-	if !handled {
-		return genericReadFrom(f, r) // without wrapping
-	}
-	return n, f.wrapErr("write", e)
-}
-
-func genericReadFrom(f *File, r io.Reader) (int64, error) {
-	return io.Copy(onlyWriter{f}, r)
-}
-
-type onlyWriter struct {
-	io.Writer
-}
-
-// Write writes len(b) bytes from b to the File.
-// It returns the number of bytes written and an error, if any.
-// Write returns a non-nil error when n != len(b).
-func (f *File) Write(b []byte) (n int, err error) {
-	if err := f.checkValid("write"); err != nil {
-		return 0, err
-	}
-	n, e := f.write(b)
-	if n < 0 {
-		n = 0
-	}
-	if n != len(b) {
-		err = io.ErrShortWrite
-	}
-
-	epipecheck(f, e)
-
-	if e != nil {
-		err = f.wrapErr("write", e)
-	}
-
-	return n, err
-}
-
-var errWriteAtInAppendMode = errors.New("os: invalid use of WriteAt on file opened with O_APPEND")
-
-// WriteAt writes len(b) bytes to the File starting at byte offset off.
-// It returns the number of bytes written and an error, if any.
-// WriteAt returns a non-nil error when n != len(b).
-//
-// If file was opened with the O_APPEND flag, WriteAt returns an error.
-func (f *File) WriteAt(b []byte, off int64) (n int, err error) {
-	if err := f.checkValid("write"); err != nil {
-		return 0, err
-	}
-	if f.appendMode {
-		return 0, errWriteAtInAppendMode
-	}
-
-	if off < 0 {
-		return 0, &PathError{Op: "writeat", Path: f.name, Err: errors.New("negative offset")}
-	}
-
-	for len(b) > 0 {
-		m, e := f.pwrite(b, off)
-		if e != nil {
-			err = f.wrapErr("write", e)
-			break
-		}
-		n += m
-		b = b[m:]
-		off += int64(m)
-	}
-	return
-}
-
-// Seek sets the offset for the next Read or Write on file to offset, interpreted
-// according to whence: 0 means relative to the origin of the file, 1 means
-// relative to the current offset, and 2 means relative to the end.
-// It returns the new offset and an error, if any.
-// The behavior of Seek on a file opened with O_APPEND is not specified.
-//
-// If f is a directory, the behavior of Seek varies by operating
-// system; you can seek to the beginning of the directory on Unix-like
-// operating systems, but not on Windows.
-func (f *File) Seek(offset int64, whence int) (ret int64, err error) {
-	if err := f.checkValid("seek"); err != nil {
-		return 0, err
-	}
-	r, e := f.seek(offset, whence)
-	if e == nil && f.dirinfo != nil && r != 0 {
-		e = syscall.EISDIR
-	}
-	if e != nil {
-		return 0, f.wrapErr("seek", e)
-	}
-	return r, nil
-}
-
-// WriteString is like Write, but writes the contents of string s rather than
-// a slice of bytes.
-func (f *File) WriteString(s string) (n int, err error) {
-	var b []byte
-	hdr := (*unsafeheader.Slice)(unsafe.Pointer(&b))
-	hdr.Data = (*unsafeheader.String)(unsafe.Pointer(&s)).Data
-	hdr.Cap = len(s)
-	hdr.Len = len(s)
-	return f.Write(b)
-}
-
-// Mkdir creates a new directory with the specified name and permission
-// bits (before umask).
-// If there is an error, it will be of type *PathError.
-func Mkdir(name string, perm FileMode) error {
-	if runtime.GOOS == "windows" && isWindowsNulName(name) {
-		return &PathError{Op: "mkdir", Path: name, Err: syscall.ENOTDIR}
-	}
-	longName := fixLongPath(name)
-	e := ignoringEINTR(func() error {
-		return syscall.Mkdir(longName, syscallMode(perm))
-	})
-
-	if e != nil {
-		return &PathError{Op: "mkdir", Path: name, Err: e}
-	}
-
-	// mkdir(2) itself won't handle the sticky bit on *BSD and Solaris
-	if !supportsCreateWithStickyBit && perm&ModeSticky != 0 {
-		e = setStickyBit(name)
-
-		if e != nil {
-			Remove(name)
-			return e
-		}
-	}
-
-	return nil
-}
-
-// setStickyBit adds ModeSticky to the permission bits of path, non atomic.
-func setStickyBit(name string) error {
-	fi, err := Stat(name)
-	if err != nil {
-		return err
-	}
-	return Chmod(name, fi.Mode()|ModeSticky)
-}
-
-// Chdir changes the current working directory to the named directory.
-// If there is an error, it will be of type *PathError.
-func Chdir(dir string) error {
-	if e := syscall.Chdir(dir); e != nil {
-		testlog.Open(dir) // observe likely non-existent directory
-		return &PathError{Op: "chdir", Path: dir, Err: e}
-	}
-	if log := testlog.Logger(); log != nil {
-		wd, err := Getwd()
-		if err == nil {
-			log.Chdir(wd)
-		}
-	}
-	return nil
-}
-
-// Open opens the named file for reading. If successful, methods on
-// the returned file can be used for reading; the associated file
-// descriptor has mode O_RDONLY.
-// If there is an error, it will be of type *PathError.
-func Open(name string) (*File, error) {
-	return OpenFile(name, O_RDONLY, 0)
-}
-
-// Create creates or truncates the named file. If the file already exists,
-// it is truncated. If the file does not exist, it is created with mode 0666
-// (before umask). If successful, methods on the returned File can
-// be used for I/O; the associated file descriptor has mode O_RDWR.
-// If there is an error, it will be of type *PathError.
-func Create(name string) (*File, error) {
-	return OpenFile(name, O_RDWR|O_CREATE|O_TRUNC, 0666)
-}
-
-// OpenFile is the generalized open call; most users will use Open
-// or Create instead. It opens the named file with specified flag
-// (O_RDONLY etc.). If the file does not exist, and the O_CREATE flag
-// is passed, it is created with mode perm (before umask). If successful,
-// methods on the returned File can be used for I/O.
-// If there is an error, it will be of type *PathError.
-func OpenFile(name string, flag int, perm FileMode) (*File, error) {
-	testlog.Open(name)
-	f, err := openFileNolog(name, flag, perm)
-	if err != nil {
-		return nil, err
-	}
-	f.appendMode = flag&O_APPEND != 0
-
-	return f, nil
-}
-
-// lstat is overridden in tests.
-var lstat = Lstat
-
-// Rename renames (moves) oldpath to newpath.
-// If newpath already exists and is not a directory, Rename replaces it.
-// OS-specific restrictions may apply when oldpath and newpath are in different directories.
-// If there is an error, it will be of type *LinkError.
-func Rename(oldpath, newpath string) error {
-	return rename(oldpath, newpath)
-}
-
-// Many functions in package syscall return a count of -1 instead of 0.
-// Using fixCount(call()) instead of call() corrects the count.
-func fixCount(n int, err error) (int, error) {
-	if n < 0 {
-		n = 0
-	}
-	return n, err
-}
-
-// wrapErr wraps an error that occurred during an operation on an open file.
-// It passes io.EOF through unchanged, otherwise converts
-// poll.ErrFileClosing to ErrClosed and wraps the error in a PathError.
-func (f *File) wrapErr(op string, err error) error {
-	if err == nil || err == io.EOF {
-		return err
-	}
-	if err == poll.ErrFileClosing {
-		err = ErrClosed
-	}
-	return &PathError{Op: op, Path: f.name, Err: err}
-}
-
-// TempDir returns the default directory to use for temporary files.
-//
-// On Unix systems, it returns $TMPDIR if non-empty, else /tmp.
-// On Windows, it uses GetTempPath, returning the first non-empty
-// value from %TMP%, %TEMP%, %USERPROFILE%, or the Windows directory.
-// On Plan 9, it returns /tmp.
-//
-// The directory is neither guaranteed to exist nor have accessible
-// permissions.
-func TempDir() string {
-	return tempDir()
-}
-
-// UserCacheDir returns the default root directory to use for user-specific
-// cached data. Users should create their own application-specific subdirectory
-// within this one and use that.
-//
-// On Unix systems, it returns $XDG_CACHE_HOME as specified by
-// https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html if
-// non-empty, else $HOME/.cache.
-// On Darwin, it returns $HOME/Library/Caches.
-// On Windows, it returns %LocalAppData%.
-// On Plan 9, it returns $home/lib/cache.
-//
-// If the location cannot be determined (for example, $HOME is not defined),
-// then it will return an error.
-func UserCacheDir() (string, error) {
-	var dir string
-
-	switch runtime.GOOS {
-	case "windows":
-		dir = Getenv("LocalAppData")
-		if dir == "" {
-			return "", errors.New("%LocalAppData% is not defined")
-		}
-
-	case "darwin", "ios":
-		dir = Getenv("HOME")
-		if dir == "" {
-			return "", errors.New("$HOME is not defined")
-		}
-		dir += "/Library/Caches"
-
-	case "plan9":
-		dir = Getenv("home")
-		if dir == "" {
-			return "", errors.New("$home is not defined")
-		}
-		dir += "/lib/cache"
-
-	default: // Unix
-		dir = Getenv("XDG_CACHE_HOME")
-		if dir == "" {
-			dir = Getenv("HOME")
-			if dir == "" {
-				return "", errors.New("neither $XDG_CACHE_HOME nor $HOME are defined")
-			}
-			dir += "/.cache"
-		}
-	}
-
-	return dir, nil
-}
-
-// UserConfigDir returns the default root directory to use for user-specific
-// configuration data. Users should create their own application-specific
-// subdirectory within this one and use that.
-//
-// On Unix systems, it returns $XDG_CONFIG_HOME as specified by
-// https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html if
-// non-empty, else $HOME/.config.
-// On Darwin, it returns $HOME/Library/Application Support.
-// On Windows, it returns %AppData%.
-// On Plan 9, it returns $home/lib.
-//
-// If the location cannot be determined (for example, $HOME is not defined),
-// then it will return an error.
-func UserConfigDir() (string, error) {
-	var dir string
-
-	switch runtime.GOOS {
-	case "windows":
-		dir = Getenv("AppData")
-		if dir == "" {
-			return "", errors.New("%AppData% is not defined")
-		}
-
-	case "darwin", "ios":
-		dir = Getenv("HOME")
-		if dir == "" {
-			return "", errors.New("$HOME is not defined")
-		}
-		dir += "/Library/Application Support"
-
-	case "plan9":
-		dir = Getenv("home")
-		if dir == "" {
-			return "", errors.New("$home is not defined")
-		}
-		dir += "/lib"
-
-	default: // Unix
-		dir = Getenv("XDG_CONFIG_HOME")
-		if dir == "" {
-			dir = Getenv("HOME")
-			if dir == "" {
-				return "", errors.New("neither $XDG_CONFIG_HOME nor $HOME are defined")
-			}
-			dir += "/.config"
-		}
-	}
-
-	return dir, nil
-}
-
-// UserHomeDir returns the current user's home directory.
-//
-// On Unix, including macOS, it returns the $HOME environment variable.
-// On Windows, it returns %USERPROFILE%.
-// On Plan 9, it returns the $home environment variable.
-func UserHomeDir() (string, error) {
-	env, enverr := "HOME", "$HOME"
-	switch runtime.GOOS {
-	case "windows":
-		env, enverr = "USERPROFILE", "%userprofile%"
-	case "plan9":
-		env, enverr = "home", "$home"
-	}
-	if v := Getenv(env); v != "" {
-		return v, nil
-	}
-	// On some geese the home directory is not always defined.
-	switch runtime.GOOS {
-	case "android":
-		return "/sdcard", nil
-	case "ios":
-		return "/", nil
-	}
-	return "", errors.New(enverr + " is not defined")
-}
-
-// Chmod changes the mode of the named file to mode.
-// If the file is a symbolic link, it changes the mode of the link's target.
-// If there is an error, it will be of type *PathError.
-//
-// A different subset of the mode bits are used, depending on the
-// operating system.
-//
-// On Unix, the mode's permission bits, ModeSetuid, ModeSetgid, and
-// ModeSticky are used.
-//
-// On Windows, only the 0200 bit (owner writable) of mode is used; it
-// controls whether the file's read-only attribute is set or cleared.
-// The other bits are currently unused. For compatibility with Go 1.12
-// and earlier, use a non-zero mode. Use mode 0400 for a read-only
-// file and 0600 for a readable+writable file.
-//
-// On Plan 9, the mode's permission bits, ModeAppend, ModeExclusive,
-// and ModeTemporary are used.
-func Chmod(name string, mode FileMode) error { return chmod(name, mode) }
-
-// Chmod changes the mode of the file to mode.
-// If there is an error, it will be of type *PathError.
-func (f *File) Chmod(mode FileMode) error { return f.chmod(mode) }
-
-// SetDeadline sets the read and write deadlines for a File.
-// It is equivalent to calling both SetReadDeadline and SetWriteDeadline.
-//
-// Only some kinds of files support setting a deadline. Calls to SetDeadline
-// for files that do not support deadlines will return ErrNoDeadline.
-// On most systems ordinary files do not support deadlines, but pipes do.
-//
-// A deadline is an absolute time after which I/O operations fail with an
-// error instead of blocking. The deadline applies to all future and pending
-// I/O, not just the immediately following call to Read or Write.
-// After a deadline has been exceeded, the connection can be refreshed
-// by setting a deadline in the future.
-//
-// If the deadline is exceeded a call to Read or Write or to other I/O
-// methods will return an error that wraps ErrDeadlineExceeded.
-// This can be tested using errors.Is(err, os.ErrDeadlineExceeded).
-// That error implements the Timeout method, and calling the Timeout
-// method will return true, but there are other possible errors for which
-// the Timeout will return true even if the deadline has not been exceeded.
-//
-// An idle timeout can be implemented by repeatedly extending
-// the deadline after successful Read or Write calls.
-//
-// A zero value for t means I/O operations will not time out.
-func (f *File) SetDeadline(t time.Time) error {
-	return f.setDeadline(t)
-}
-
-// SetReadDeadline sets the deadline for future Read calls and any
-// currently-blocked Read call.
-// A zero value for t means Read will not time out.
-// Not all files support setting deadlines; see SetDeadline.
-func (f *File) SetReadDeadline(t time.Time) error {
-	return f.setReadDeadline(t)
-}
-
-// SetWriteDeadline sets the deadline for any future Write calls and any
-// currently-blocked Write call.
-// Even if Write times out, it may return n > 0, indicating that
-// some of the data was successfully written.
-// A zero value for t means Write will not time out.
-// Not all files support setting deadlines; see SetDeadline.
-func (f *File) SetWriteDeadline(t time.Time) error {
-	return f.setWriteDeadline(t)
-}
-
-// SyscallConn returns a raw file.
-// This implements the syscall.Conn interface.
-func (f *File) SyscallConn() (syscall.RawConn, error) {
-	if err := f.checkValid("SyscallConn"); err != nil {
-		return nil, err
-	}
-	return newRawConn(f)
-}
-
-// isWindowsNulName reports whether name is os.DevNull ('NUL') on Windows.
-// True is returned if name is 'NUL' whatever the case.
-func isWindowsNulName(name string) bool {
-	if len(name) != 3 {
-		return false
-	}
-	if name[0] != 'n' && name[0] != 'N' {
-		return false
-	}
-	if name[1] != 'u' && name[1] != 'U' {
-		return false
-	}
-	if name[2] != 'l' && name[2] != 'L' {
-		return false
-	}
-	return true
-}
-
-// DirFS returns a file system (an fs.FS) for the tree of files rooted at the directory dir.
-//
-// Note that DirFS("/prefix") only guarantees that the Open calls it makes to the
-// operating system will begin with "/prefix": DirFS("/prefix").Open("file") is the
-// same as os.Open("/prefix/file"). So if /prefix/file is a symbolic link pointing outside
-// the /prefix tree, then using DirFS does not stop the access any more than using
-// os.Open does. DirFS is therefore not a general substitute for a chroot-style security
-// mechanism when the directory tree contains arbitrary content.
-func DirFS(dir string) fs.FS {
-	return dirFS(dir)
-}
-
-func containsAny(s, chars string) bool {
-	for i := 0; i < len(s); i++ {
-		for j := 0; j < len(chars); j++ {
-			if s[i] == chars[j] {
-				return true
-			}
-		}
-	}
-	return false
-}
-
-type dirFS string
-
-func (dir dirFS) Open(name string) (fs.File, error) {
-	if !fs.ValidPath(name) || runtime.GOOS == "windows" && containsAny(name, `\:`) {
-		return nil, &PathError{Op: "open", Path: name, Err: ErrInvalid}
-	}
-	f, err := Open(string(dir) + "/" + name)
-	if err != nil {
-		return nil, err // nil fs.File
-	}
-	return f, nil
-}
-
-func (dir dirFS) Stat(name string) (fs.FileInfo, error) {
-	if !fs.ValidPath(name) || runtime.GOOS == "windows" && containsAny(name, `\:`) {
-		return nil, &PathError{Op: "stat", Path: name, Err: ErrInvalid}
-	}
-	f, err := Stat(string(dir) + "/" + name)
-	if err != nil {
-		return nil, err
-	}
-	return f, nil
-}
-
-// ReadFile reads the named file and returns the contents.
-// A successful call returns err == nil, not err == EOF.
-// Because ReadFile reads the whole file, it does not treat an EOF from Read
-// as an error to be reported.
-func ReadFile(name string) ([]byte, error) {
-	f, err := Open(name)
-	if err != nil {
-		return nil, err
-	}
-	defer f.Close()
-
-	var size int
-	if info, err := f.Stat(); err == nil {
-		size64 := info.Size()
-		if int64(int(size64)) == size64 {
-			size = int(size64)
-		}
-	}
-	size++ // one byte for final read at EOF
-
-	// If a file claims a small size, read at least 512 bytes.
-	// In particular, files in Linux's /proc claim size 0 but
-	// then do not work right if read in small pieces,
-	// so an initial read of 1 byte would not work correctly.
-	if size < 512 {
-		size = 512
-	}
-
-	data := make([]byte, 0, size)
-	for {
-		if len(data) >= cap(data) {
-			d := append(data[:cap(data)], 0)
-			data = d[:len(data)]
-		}
-		n, err := f.Read(data[len(data):cap(data)])
-		data = data[:len(data)+n]
-		if err != nil {
-			if err == io.EOF {
-				err = nil
-			}
-			return data, err
-		}
-	}
-}
-
-// WriteFile writes data to the named file, creating it if necessary.
-// If the file does not exist, WriteFile creates it with permissions perm (before umask);
-// otherwise WriteFile truncates it before writing, without changing permissions.
-func WriteFile(name string, data []byte, perm FileMode) error {
-	f, err := OpenFile(name, O_WRONLY|O_CREATE|O_TRUNC, perm)
-	if err != nil {
-		return err
-	}
-	_, err = f.Write(data)
-	if err1 := f.Close(); err1 != nil && err == nil {
-		err = err1
-	}
-	return err
-}
diff --git a/contrib/go/_std_1.18/src/os/file_posix.go b/contrib/go/_std_1.18/src/os/file_posix.go
deleted file mode 100644
index f34571d68d..0000000000
--- a/contrib/go/_std_1.18/src/os/file_posix.go
+++ /dev/null
@@ -1,250 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris || windows
-
-package os
-
-import (
-	"runtime"
-	"syscall"
-	"time"
-)
-
-func sigpipe() // implemented in package runtime
-
-// Close closes the File, rendering it unusable for I/O.
-// On files that support SetDeadline, any pending I/O operations will
-// be canceled and return immediately with an ErrClosed error.
-// Close will return an error if it has already been called.
-func (f *File) Close() error {
-	if f == nil {
-		return ErrInvalid
-	}
-	return f.file.close()
-}
-
-// read reads up to len(b) bytes from the File.
-// It returns the number of bytes read and an error, if any.
-func (f *File) read(b []byte) (n int, err error) {
-	n, err = f.pfd.Read(b)
-	runtime.KeepAlive(f)
-	return n, err
-}
-
-// pread reads len(b) bytes from the File starting at byte offset off.
-// It returns the number of bytes read and the error, if any.
-// EOF is signaled by a zero count with err set to nil.
-func (f *File) pread(b []byte, off int64) (n int, err error) {
-	n, err = f.pfd.Pread(b, off)
-	runtime.KeepAlive(f)
-	return n, err
-}
-
-// write writes len(b) bytes to the File.
-// It returns the number of bytes written and an error, if any.
-func (f *File) write(b []byte) (n int, err error) {
-	n, err = f.pfd.Write(b)
-	runtime.KeepAlive(f)
-	return n, err
-}
-
-// pwrite writes len(b) bytes to the File starting at byte offset off.
-// It returns the number of bytes written and an error, if any.
-func (f *File) pwrite(b []byte, off int64) (n int, err error) {
-	n, err = f.pfd.Pwrite(b, off)
-	runtime.KeepAlive(f)
-	return n, err
-}
-
-// syscallMode returns the syscall-specific mode bits from Go's portable mode bits.
-func syscallMode(i FileMode) (o uint32) {
-	o |= uint32(i.Perm())
-	if i&ModeSetuid != 0 {
-		o |= syscall.S_ISUID
-	}
-	if i&ModeSetgid != 0 {
-		o |= syscall.S_ISGID
-	}
-	if i&ModeSticky != 0 {
-		o |= syscall.S_ISVTX
-	}
-	// No mapping for Go's ModeTemporary (plan9 only).
-	return
-}
-
-// See docs in file.go:Chmod.
-func chmod(name string, mode FileMode) error {
-	longName := fixLongPath(name)
-	e := ignoringEINTR(func() error {
-		return syscall.Chmod(longName, syscallMode(mode))
-	})
-	if e != nil {
-		return &PathError{Op: "chmod", Path: name, Err: e}
-	}
-	return nil
-}
-
-// See docs in file.go:(*File).Chmod.
-func (f *File) chmod(mode FileMode) error {
-	if err := f.checkValid("chmod"); err != nil {
-		return err
-	}
-	if e := f.pfd.Fchmod(syscallMode(mode)); e != nil {
-		return f.wrapErr("chmod", e)
-	}
-	return nil
-}
-
-// Chown changes the numeric uid and gid of the named file.
-// If the file is a symbolic link, it changes the uid and gid of the link's target.
-// A uid or gid of -1 means to not change that value.
-// If there is an error, it will be of type *PathError.
-//
-// On Windows or Plan 9, Chown always returns the syscall.EWINDOWS or
-// EPLAN9 error, wrapped in *PathError.
-func Chown(name string, uid, gid int) error {
-	e := ignoringEINTR(func() error {
-		return syscall.Chown(name, uid, gid)
-	})
-	if e != nil {
-		return &PathError{Op: "chown", Path: name, Err: e}
-	}
-	return nil
-}
-
-// Lchown changes the numeric uid and gid of the named file.
-// If the file is a symbolic link, it changes the uid and gid of the link itself.
-// If there is an error, it will be of type *PathError.
-//
-// On Windows, it always returns the syscall.EWINDOWS error, wrapped
-// in *PathError.
-func Lchown(name string, uid, gid int) error {
-	e := ignoringEINTR(func() error {
-		return syscall.Lchown(name, uid, gid)
-	})
-	if e != nil {
-		return &PathError{Op: "lchown", Path: name, Err: e}
-	}
-	return nil
-}
-
-// Chown changes the numeric uid and gid of the named file.
-// If there is an error, it will be of type *PathError.
-//
-// On Windows, it always returns the syscall.EWINDOWS error, wrapped
-// in *PathError.
-func (f *File) Chown(uid, gid int) error {
-	if err := f.checkValid("chown"); err != nil {
-		return err
-	}
-	if e := f.pfd.Fchown(uid, gid); e != nil {
-		return f.wrapErr("chown", e)
-	}
-	return nil
-}
-
-// Truncate changes the size of the file.
-// It does not change the I/O offset.
-// If there is an error, it will be of type *PathError.
-func (f *File) Truncate(size int64) error {
-	if err := f.checkValid("truncate"); err != nil {
-		return err
-	}
-	if e := f.pfd.Ftruncate(size); e != nil {
-		return f.wrapErr("truncate", e)
-	}
-	return nil
-}
-
-// Sync commits the current contents of the file to stable storage.
-// Typically, this means flushing the file system's in-memory copy
-// of recently written data to disk.
-func (f *File) Sync() error {
-	if err := f.checkValid("sync"); err != nil {
-		return err
-	}
-	if e := f.pfd.Fsync(); e != nil {
-		return f.wrapErr("sync", e)
-	}
-	return nil
-}
-
-// Chtimes changes the access and modification times of the named
-// file, similar to the Unix utime() or utimes() functions.
-//
-// The underlying filesystem may truncate or round the values to a
-// less precise time unit.
-// If there is an error, it will be of type *PathError.
-func Chtimes(name string, atime time.Time, mtime time.Time) error {
-	var utimes [2]syscall.Timespec
-	utimes[0] = syscall.NsecToTimespec(atime.UnixNano())
-	utimes[1] = syscall.NsecToTimespec(mtime.UnixNano())
-	if e := syscall.UtimesNano(fixLongPath(name), utimes[0:]); e != nil {
-		return &PathError{Op: "chtimes", Path: name, Err: e}
-	}
-	return nil
-}
-
-// Chdir changes the current working directory to the file,
-// which must be a directory.
-// If there is an error, it will be of type *PathError.
-func (f *File) Chdir() error {
-	if err := f.checkValid("chdir"); err != nil {
-		return err
-	}
-	if e := f.pfd.Fchdir(); e != nil {
-		return f.wrapErr("chdir", e)
-	}
-	return nil
-}
-
-// setDeadline sets the read and write deadline.
-func (f *File) setDeadline(t time.Time) error {
-	if err := f.checkValid("SetDeadline"); err != nil {
-		return err
-	}
-	return f.pfd.SetDeadline(t)
-}
-
-// setReadDeadline sets the read deadline.
-func (f *File) setReadDeadline(t time.Time) error {
-	if err := f.checkValid("SetReadDeadline"); err != nil {
-		return err
-	}
-	return f.pfd.SetReadDeadline(t)
-}
-
-// setWriteDeadline sets the write deadline.
-func (f *File) setWriteDeadline(t time.Time) error {
-	if err := f.checkValid("SetWriteDeadline"); err != nil {
-		return err
-	}
-	return f.pfd.SetWriteDeadline(t)
-}
-
-// checkValid checks whether f is valid for use.
-// If not, it returns an appropriate error, perhaps incorporating the operation name op.
-func (f *File) checkValid(op string) error {
-	if f == nil {
-		return ErrInvalid
-	}
-	return nil
-}
-
-// ignoringEINTR makes a function call and repeats it if it returns an
-// EINTR error. This appears to be required even though we install all
-// signal handlers with SA_RESTART: see #22838, #38033, #38836, #40846.
-// Also #20400 and #36644 are issues in which a signal handler is
-// installed without setting SA_RESTART. None of these are the common case,
-// but there are enough of them that it seems that we can't avoid
-// an EINTR loop.
-func ignoringEINTR(fn func() error) error {
-	for {
-		err := fn()
-		if err != syscall.EINTR {
-			return err
-		}
-	}
-}
diff --git a/contrib/go/_std_1.18/src/os/file_unix.go b/contrib/go/_std_1.18/src/os/file_unix.go
deleted file mode 100644
index a38db18954..0000000000
--- a/contrib/go/_std_1.18/src/os/file_unix.go
+++ /dev/null
@@ -1,430 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris
-
-package os
-
-import (
-	"internal/poll"
-	"internal/syscall/unix"
-	"runtime"
-	"syscall"
-)
-
-// fixLongPath is a noop on non-Windows platforms.
-func fixLongPath(path string) string {
-	return path
-}
-
-func rename(oldname, newname string) error {
-	fi, err := Lstat(newname)
-	if err == nil && fi.IsDir() {
-		// There are two independent errors this function can return:
-		// one for a bad oldname, and one for a bad newname.
-		// At this point we've determined the newname is bad.
-		// But just in case oldname is also bad, prioritize returning
-		// the oldname error because that's what we did historically.
-		// However, if the old name and new name are not the same, yet
-		// they refer to the same file, it implies a case-only
-		// rename on a case-insensitive filesystem, which is ok.
-		if ofi, err := Lstat(oldname); err != nil {
-			if pe, ok := err.(*PathError); ok {
-				err = pe.Err
-			}
-			return &LinkError{"rename", oldname, newname, err}
-		} else if newname == oldname || !SameFile(fi, ofi) {
-			return &LinkError{"rename", oldname, newname, syscall.EEXIST}
-		}
-	}
-	err = ignoringEINTR(func() error {
-		return syscall.Rename(oldname, newname)
-	})
-	if err != nil {
-		return &LinkError{"rename", oldname, newname, err}
-	}
-	return nil
-}
-
-// file is the real representation of *File.
-// The extra level of indirection ensures that no clients of os
-// can overwrite this data, which could cause the finalizer
-// to close the wrong file descriptor.
-type file struct {
-	pfd         poll.FD
-	name        string
-	dirinfo     *dirInfo // nil unless directory being read
-	nonblock    bool     // whether we set nonblocking mode
-	stdoutOrErr bool     // whether this is stdout or stderr
-	appendMode  bool     // whether file is opened for appending
-}
-
-// Fd returns the integer Unix file descriptor referencing the open file.
-// If f is closed, the file descriptor becomes invalid.
-// If f is garbage collected, a finalizer may close the file descriptor,
-// making it invalid; see runtime.SetFinalizer for more information on when
-// a finalizer might be run. On Unix systems this will cause the SetDeadline
-// methods to stop working.
-// Because file descriptors can be reused, the returned file descriptor may
-// only be closed through the Close method of f, or by its finalizer during
-// garbage collection. Otherwise, during garbage collection the finalizer
-// may close an unrelated file descriptor with the same (reused) number.
-//
-// As an alternative, see the f.SyscallConn method.
-func (f *File) Fd() uintptr {
-	if f == nil {
-		return ^(uintptr(0))
-	}
-
-	// If we put the file descriptor into nonblocking mode,
-	// then set it to blocking mode before we return it,
-	// because historically we have always returned a descriptor
-	// opened in blocking mode. The File will continue to work,
-	// but any blocking operation will tie up a thread.
-	if f.nonblock {
-		f.pfd.SetBlocking()
-	}
-
-	return uintptr(f.pfd.Sysfd)
-}
-
-// NewFile returns a new File with the given file descriptor and
-// name. The returned value will be nil if fd is not a valid file
-// descriptor. On Unix systems, if the file descriptor is in
-// non-blocking mode, NewFile will attempt to return a pollable File
-// (one for which the SetDeadline methods work).
-//
-// After passing it to NewFile, fd may become invalid under the same
-// conditions described in the comments of the Fd method, and the same
-// constraints apply.
-func NewFile(fd uintptr, name string) *File {
-	kind := kindNewFile
-	if nb, err := unix.IsNonblock(int(fd)); err == nil && nb {
-		kind = kindNonBlock
-	}
-	return newFile(fd, name, kind)
-}
-
-// newFileKind describes the kind of file to newFile.
-type newFileKind int
-
-const (
-	kindNewFile newFileKind = iota
-	kindOpenFile
-	kindPipe
-	kindNonBlock
-)
-
-// newFile is like NewFile, but if called from OpenFile or Pipe
-// (as passed in the kind parameter) it tries to add the file to
-// the runtime poller.
-func newFile(fd uintptr, name string, kind newFileKind) *File {
-	fdi := int(fd)
-	if fdi < 0 {
-		return nil
-	}
-	f := &File{&file{
-		pfd: poll.FD{
-			Sysfd:         fdi,
-			IsStream:      true,
-			ZeroReadIsEOF: true,
-		},
-		name:        name,
-		stdoutOrErr: fdi == 1 || fdi == 2,
-	}}
-
-	pollable := kind == kindOpenFile || kind == kindPipe || kind == kindNonBlock
-
-	// If the caller passed a non-blocking filedes (kindNonBlock),
-	// we assume they know what they are doing so we allow it to be
-	// used with kqueue.
-	if kind == kindOpenFile {
-		switch runtime.GOOS {
-		case "darwin", "ios", "dragonfly", "freebsd", "netbsd", "openbsd":
-			var st syscall.Stat_t
-			err := ignoringEINTR(func() error {
-				return syscall.Fstat(fdi, &st)
-			})
-			typ := st.Mode & syscall.S_IFMT
-			// Don't try to use kqueue with regular files on *BSDs.
-			// On FreeBSD a regular file is always
-			// reported as ready for writing.
-			// On Dragonfly, NetBSD and OpenBSD the fd is signaled
-			// only once as ready (both read and write).
-			// Issue 19093.
-			// Also don't add directories to the netpoller.
-			if err == nil && (typ == syscall.S_IFREG || typ == syscall.S_IFDIR) {
-				pollable = false
-			}
-
-			// In addition to the behavior described above for regular files,
-			// on Darwin, kqueue does not work properly with fifos:
-			// closing the last writer does not cause a kqueue event
-			// for any readers. See issue #24164.
-			if (runtime.GOOS == "darwin" || runtime.GOOS == "ios") && typ == syscall.S_IFIFO {
-				pollable = false
-			}
-		}
-	}
-
-	if err := f.pfd.Init("file", pollable); err != nil {
-		// An error here indicates a failure to register
-		// with the netpoll system. That can happen for
-		// a file descriptor that is not supported by
-		// epoll/kqueue; for example, disk files on
-		// Linux systems. We assume that any real error
-		// will show up in later I/O.
-	} else if pollable {
-		// We successfully registered with netpoll, so put
-		// the file into nonblocking mode.
-		if err := syscall.SetNonblock(fdi, true); err == nil {
-			f.nonblock = true
-		}
-	}
-
-	runtime.SetFinalizer(f.file, (*file).close)
-	return f
-}
-
-// epipecheck raises SIGPIPE if we get an EPIPE error on standard
-// output or standard error. See the SIGPIPE docs in os/signal, and
-// issue 11845.
-func epipecheck(file *File, e error) {
-	if e == syscall.EPIPE && file.stdoutOrErr {
-		sigpipe()
-	}
-}
-
-// DevNull is the name of the operating system's ``null device.''
-// On Unix-like systems, it is "/dev/null"; on Windows, "NUL".
-const DevNull = "/dev/null"
-
-// openFileNolog is the Unix implementation of OpenFile.
-// Changes here should be reflected in openFdAt, if relevant.
-func openFileNolog(name string, flag int, perm FileMode) (*File, error) {
-	setSticky := false
-	if !supportsCreateWithStickyBit && flag&O_CREATE != 0 && perm&ModeSticky != 0 {
-		if _, err := Stat(name); IsNotExist(err) {
-			setSticky = true
-		}
-	}
-
-	var r int
-	for {
-		var e error
-		r, e = syscall.Open(name, flag|syscall.O_CLOEXEC, syscallMode(perm))
-		if e == nil {
-			break
-		}
-
-		// We have to check EINTR here, per issues 11180 and 39237.
-		if e == syscall.EINTR {
-			continue
-		}
-
-		return nil, &PathError{Op: "open", Path: name, Err: e}
-	}
-
-	// open(2) itself won't handle the sticky bit on *BSD and Solaris
-	if setSticky {
-		setStickyBit(name)
-	}
-
-	// There's a race here with fork/exec, which we are
-	// content to live with. See ../syscall/exec_unix.go.
-	if !supportsCloseOnExec {
-		syscall.CloseOnExec(r)
-	}
-
-	return newFile(uintptr(r), name, kindOpenFile), nil
-}
-
-func (file *file) close() error {
-	if file == nil {
-		return syscall.EINVAL
-	}
-	if file.dirinfo != nil {
-		file.dirinfo.close()
-		file.dirinfo = nil
-	}
-	var err error
-	if e := file.pfd.Close(); e != nil {
-		if e == poll.ErrFileClosing {
-			e = ErrClosed
-		}
-		err = &PathError{Op: "close", Path: file.name, Err: e}
-	}
-
-	// no need for a finalizer anymore
-	runtime.SetFinalizer(file, nil)
-	return err
-}
-
-// seek sets the offset for the next Read or Write on file to offset, interpreted
-// according to whence: 0 means relative to the origin of the file, 1 means
-// relative to the current offset, and 2 means relative to the end.
-// It returns the new offset and an error, if any.
-func (f *File) seek(offset int64, whence int) (ret int64, err error) {
-	if f.dirinfo != nil {
-		// Free cached dirinfo, so we allocate a new one if we
-		// access this file as a directory again. See #35767 and #37161.
-		f.dirinfo.close()
-		f.dirinfo = nil
-	}
-	ret, err = f.pfd.Seek(offset, whence)
-	runtime.KeepAlive(f)
-	return ret, err
-}
-
-// Truncate changes the size of the named file.
-// If the file is a symbolic link, it changes the size of the link's target.
-// If there is an error, it will be of type *PathError.
-func Truncate(name string, size int64) error {
-	e := ignoringEINTR(func() error {
-		return syscall.Truncate(name, size)
-	})
-	if e != nil {
-		return &PathError{Op: "truncate", Path: name, Err: e}
-	}
-	return nil
-}
-
-// Remove removes the named file or (empty) directory.
-// If there is an error, it will be of type *PathError.
-func Remove(name string) error {
-	// System call interface forces us to know
-	// whether name is a file or directory.
-	// Try both: it is cheaper on average than
-	// doing a Stat plus the right one.
-	e := ignoringEINTR(func() error {
-		return syscall.Unlink(name)
-	})
-	if e == nil {
-		return nil
-	}
-	e1 := ignoringEINTR(func() error {
-		return syscall.Rmdir(name)
-	})
-	if e1 == nil {
-		return nil
-	}
-
-	// Both failed: figure out which error to return.
-	// OS X and Linux differ on whether unlink(dir)
-	// returns EISDIR, so can't use that. However,
-	// both agree that rmdir(file) returns ENOTDIR,
-	// so we can use that to decide which error is real.
-	// Rmdir might also return ENOTDIR if given a bad
-	// file path, like /etc/passwd/foo, but in that case,
-	// both errors will be ENOTDIR, so it's okay to
-	// use the error from unlink.
-	if e1 != syscall.ENOTDIR {
-		e = e1
-	}
-	return &PathError{Op: "remove", Path: name, Err: e}
-}
-
-func tempDir() string {
-	dir := Getenv("TMPDIR")
-	if dir == "" {
-		if runtime.GOOS == "android" {
-			dir = "/data/local/tmp"
-		} else {
-			dir = "/tmp"
-		}
-	}
-	return dir
-}
-
-// Link creates newname as a hard link to the oldname file.
-// If there is an error, it will be of type *LinkError.
-func Link(oldname, newname string) error {
-	e := ignoringEINTR(func() error {
-		return syscall.Link(oldname, newname)
-	})
-	if e != nil {
-		return &LinkError{"link", oldname, newname, e}
-	}
-	return nil
-}
-
-// Symlink creates newname as a symbolic link to oldname.
-// On Windows, a symlink to a non-existent oldname creates a file symlink;
-// if oldname is later created as a directory the symlink will not work.
-// If there is an error, it will be of type *LinkError.
-func Symlink(oldname, newname string) error {
-	e := ignoringEINTR(func() error {
-		return syscall.Symlink(oldname, newname)
-	})
-	if e != nil {
-		return &LinkError{"symlink", oldname, newname, e}
-	}
-	return nil
-}
-
-// Readlink returns the destination of the named symbolic link.
-// If there is an error, it will be of type *PathError.
-func Readlink(name string) (string, error) {
-	for len := 128; ; len *= 2 {
-		b := make([]byte, len)
-		var (
-			n int
-			e error
-		)
-		for {
-			n, e = fixCount(syscall.Readlink(name, b))
-			if e != syscall.EINTR {
-				break
-			}
-		}
-		// buffer too small
-		if runtime.GOOS == "aix" && e == syscall.ERANGE {
-			continue
-		}
-		if e != nil {
-			return "", &PathError{Op: "readlink", Path: name, Err: e}
-		}
-		if n < len {
-			return string(b[0:n]), nil
-		}
-	}
-}
-
-type unixDirent struct {
-	parent string
-	name   string
-	typ    FileMode
-	info   FileInfo
-}
-
-func (d *unixDirent) Name() string   { return d.name }
-func (d *unixDirent) IsDir() bool    { return d.typ.IsDir() }
-func (d *unixDirent) Type() FileMode { return d.typ }
-
-func (d *unixDirent) Info() (FileInfo, error) {
-	if d.info != nil {
-		return d.info, nil
-	}
-	return lstat(d.parent + "/" + d.name)
-}
-
-func newUnixDirent(parent, name string, typ FileMode) (DirEntry, error) {
-	ude := &unixDirent{
-		parent: parent,
-		name:   name,
-		typ:    typ,
-	}
-	if typ != ^FileMode(0) && !testingForceReadDirLstat {
-		return ude, nil
-	}
-
-	info, err := lstat(parent + "/" + name)
-	if err != nil {
-		return nil, err
-	}
-
-	ude.typ = info.Mode().Type()
-	ude.info = info
-	return ude, nil
-}
diff --git a/contrib/go/_std_1.18/src/os/path_unix.go b/contrib/go/_std_1.18/src/os/path_unix.go
deleted file mode 100644
index d1ffe2c187..0000000000
--- a/contrib/go/_std_1.18/src/os/path_unix.go
+++ /dev/null
@@ -1,75 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris
-
-package os
-
-const (
-	PathSeparator     = '/' // OS-specific path separator
-	PathListSeparator = ':' // OS-specific path list separator
-)
-
-// IsPathSeparator reports whether c is a directory separator character.
-func IsPathSeparator(c uint8) bool {
-	return PathSeparator == c
-}
-
-// basename removes trailing slashes and the leading directory name from path name.
-func basename(name string) string {
-	i := len(name) - 1
-	// Remove trailing slashes
-	for ; i > 0 && name[i] == '/'; i-- {
-		name = name[:i]
-	}
-	// Remove leading directory name
-	for i--; i >= 0; i-- {
-		if name[i] == '/' {
-			name = name[i+1:]
-			break
-		}
-	}
-
-	return name
-}
-
-// splitPath returns the base name and parent directory.
-func splitPath(path string) (string, string) {
-	// if no better parent is found, the path is relative from "here"
-	dirname := "."
-
-	// Remove all but one leading slash.
-	for len(path) > 1 && path[0] == '/' && path[1] == '/' {
-		path = path[1:]
-	}
-
-	i := len(path) - 1
-
-	// Remove trailing slashes.
-	for ; i > 0 && path[i] == '/'; i-- {
-		path = path[:i]
-	}
-
-	// if no slashes in path, base is path
-	basename := path
-
-	// Remove leading directory path
-	for i--; i >= 0; i-- {
-		if path[i] == '/' {
-			if i == 0 {
-				dirname = path[:1]
-			} else {
-				dirname = path[:i]
-			}
-			basename = path[i+1:]
-			break
-		}
-	}
-
-	return dirname, basename
-}
-
-func fixRootDirectory(p string) string {
-	return p
-}
diff --git a/contrib/go/_std_1.18/src/os/pipe_bsd.go b/contrib/go/_std_1.18/src/os/pipe_bsd.go
deleted file mode 100644
index 554d62111a..0000000000
--- a/contrib/go/_std_1.18/src/os/pipe_bsd.go
+++ /dev/null
@@ -1,28 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || (js && wasm) || (solaris && !illumos)
-
-package os
-
-import "syscall"
-
-// Pipe returns a connected pair of Files; reads from r return bytes written to w.
-// It returns the files and an error, if any.
-func Pipe() (r *File, w *File, err error) {
-	var p [2]int
-
-	// See ../syscall/exec.go for description of lock.
-	syscall.ForkLock.RLock()
-	e := syscall.Pipe(p[0:])
-	if e != nil {
-		syscall.ForkLock.RUnlock()
-		return nil, nil, NewSyscallError("pipe", e)
-	}
-	syscall.CloseOnExec(p[0])
-	syscall.CloseOnExec(p[1])
-	syscall.ForkLock.RUnlock()
-
-	return newFile(uintptr(p[0]), "|0", kindPipe), newFile(uintptr(p[1]), "|1", kindPipe), nil
-}
diff --git a/contrib/go/_std_1.18/src/os/pipe_linux.go b/contrib/go/_std_1.18/src/os/pipe_linux.go
deleted file mode 100644
index 52f4e21e7c..0000000000
--- a/contrib/go/_std_1.18/src/os/pipe_linux.go
+++ /dev/null
@@ -1,20 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package os
-
-import "syscall"
-
-// Pipe returns a connected pair of Files; reads from r return bytes written to w.
-// It returns the files and an error, if any.
-func Pipe() (r *File, w *File, err error) {
-	var p [2]int
-
-	e := syscall.Pipe2(p[0:], syscall.O_CLOEXEC)
-	if e != nil {
-		return nil, nil, NewSyscallError("pipe2", e)
-	}
-
-	return newFile(uintptr(p[0]), "|0", kindPipe), newFile(uintptr(p[1]), "|1", kindPipe), nil
-}
diff --git a/contrib/go/_std_1.18/src/os/removeall_at.go b/contrib/go/_std_1.18/src/os/removeall_at.go
deleted file mode 100644
index da804c436f..0000000000
--- a/contrib/go/_std_1.18/src/os/removeall_at.go
+++ /dev/null
@@ -1,192 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
-
-package os
-
-import (
-	"internal/syscall/unix"
-	"io"
-	"syscall"
-)
-
-func removeAll(path string) error {
-	if path == "" {
-		// fail silently to retain compatibility with previous behavior
-		// of RemoveAll. See issue 28830.
-		return nil
-	}
-
-	// The rmdir system call does not permit removing ".",
-	// so we don't permit it either.
-	if endsWithDot(path) {
-		return &PathError{Op: "RemoveAll", Path: path, Err: syscall.EINVAL}
-	}
-
-	// Simple case: if Remove works, we're done.
-	err := Remove(path)
-	if err == nil || IsNotExist(err) {
-		return nil
-	}
-
-	// RemoveAll recurses by deleting the path base from
-	// its parent directory
-	parentDir, base := splitPath(path)
-
-	parent, err := Open(parentDir)
-	if IsNotExist(err) {
-		// If parent does not exist, base cannot exist. Fail silently
-		return nil
-	}
-	if err != nil {
-		return err
-	}
-	defer parent.Close()
-
-	if err := removeAllFrom(parent, base); err != nil {
-		if pathErr, ok := err.(*PathError); ok {
-			pathErr.Path = parentDir + string(PathSeparator) + pathErr.Path
-			err = pathErr
-		}
-		return err
-	}
-	return nil
-}
-
-func removeAllFrom(parent *File, base string) error {
-	parentFd := int(parent.Fd())
-	// Simple case: if Unlink (aka remove) works, we're done.
-	err := unix.Unlinkat(parentFd, base, 0)
-	if err == nil || IsNotExist(err) {
-		return nil
-	}
-
-	// EISDIR means that we have a directory, and we need to
-	// remove its contents.
-	// EPERM or EACCES means that we don't have write permission on
-	// the parent directory, but this entry might still be a directory
-	// whose contents need to be removed.
-	// Otherwise just return the error.
-	if err != syscall.EISDIR && err != syscall.EPERM && err != syscall.EACCES {
-		return &PathError{Op: "unlinkat", Path: base, Err: err}
-	}
-
-	// Is this a directory we need to recurse into?
-	var statInfo syscall.Stat_t
-	statErr := unix.Fstatat(parentFd, base, &statInfo, unix.AT_SYMLINK_NOFOLLOW)
-	if statErr != nil {
-		if IsNotExist(statErr) {
-			return nil
-		}
-		return &PathError{Op: "fstatat", Path: base, Err: statErr}
-	}
-	if statInfo.Mode&syscall.S_IFMT != syscall.S_IFDIR {
-		// Not a directory; return the error from the unix.Unlinkat.
-		return &PathError{Op: "unlinkat", Path: base, Err: err}
-	}
-
-	// Remove the directory's entries.
-	var recurseErr error
-	for {
-		const reqSize = 1024
-		var respSize int
-
-		// Open the directory to recurse into
-		file, err := openFdAt(parentFd, base)
-		if err != nil {
-			if IsNotExist(err) {
-				return nil
-			}
-			recurseErr = &PathError{Op: "openfdat", Path: base, Err: err}
-			break
-		}
-
-		for {
-			numErr := 0
-
-			names, readErr := file.Readdirnames(reqSize)
-			// Errors other than EOF should stop us from continuing.
-			if readErr != nil && readErr != io.EOF {
-				file.Close()
-				if IsNotExist(readErr) {
-					return nil
-				}
-				return &PathError{Op: "readdirnames", Path: base, Err: readErr}
-			}
-
-			respSize = len(names)
-			for _, name := range names {
-				err := removeAllFrom(file, name)
-				if err != nil {
-					if pathErr, ok := err.(*PathError); ok {
-						pathErr.Path = base + string(PathSeparator) + pathErr.Path
-					}
-					numErr++
-					if recurseErr == nil {
-						recurseErr = err
-					}
-				}
-			}
-
-			// If we can delete any entry, break to start new iteration.
-			// Otherwise, we discard current names, get next entries and try deleting them.
-			if numErr != reqSize {
-				break
-			}
-		}
-
-		// Removing files from the directory may have caused
-		// the OS to reshuffle it. Simply calling Readdirnames
-		// again may skip some entries. The only reliable way
-		// to avoid this is to close and re-open the
-		// directory. See issue 20841.
-		file.Close()
-
-		// Finish when the end of the directory is reached
-		if respSize < reqSize {
-			break
-		}
-	}
-
-	// Remove the directory itself.
-	unlinkError := unix.Unlinkat(parentFd, base, unix.AT_REMOVEDIR)
-	if unlinkError == nil || IsNotExist(unlinkError) {
-		return nil
-	}
-
-	if recurseErr != nil {
-		return recurseErr
-	}
-	return &PathError{Op: "unlinkat", Path: base, Err: unlinkError}
-}
-
-// openFdAt opens path relative to the directory in fd.
-// Other than that this should act like openFileNolog.
-// This acts like openFileNolog rather than OpenFile because
-// we are going to (try to) remove the file.
-// The contents of this file are not relevant for test caching.
-func openFdAt(dirfd int, name string) (*File, error) {
-	var r int
-	for {
-		var e error
-		r, e = unix.Openat(dirfd, name, O_RDONLY|syscall.O_CLOEXEC, 0)
-		if e == nil {
-			break
-		}
-
-		// See comment in openFileNolog.
-		if e == syscall.EINTR {
-			continue
-		}
-
-		return nil, e
-	}
-
-	if !supportsCloseOnExec {
-		syscall.CloseOnExec(r)
-	}
-
-	return newFile(uintptr(r), name, kindOpenFile), nil
-}
diff --git a/contrib/go/_std_1.18/src/os/stat_darwin.go b/contrib/go/_std_1.18/src/os/stat_darwin.go
deleted file mode 100644
index 74214cefa4..0000000000
--- a/contrib/go/_std_1.18/src/os/stat_darwin.go
+++ /dev/null
@@ -1,51 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package os
-
-import (
-	"syscall"
-	"time"
-)
-
-func fillFileStatFromSys(fs *fileStat, name string) {
-	fs.name = basename(name)
-	fs.size = fs.sys.Size
-	fs.modTime = timespecToTime(fs.sys.Mtimespec)
-	fs.mode = FileMode(fs.sys.Mode & 0777)
-	switch fs.sys.Mode & syscall.S_IFMT {
-	case syscall.S_IFBLK, syscall.S_IFWHT:
-		fs.mode |= ModeDevice
-	case syscall.S_IFCHR:
-		fs.mode |= ModeDevice | ModeCharDevice
-	case syscall.S_IFDIR:
-		fs.mode |= ModeDir
-	case syscall.S_IFIFO:
-		fs.mode |= ModeNamedPipe
-	case syscall.S_IFLNK:
-		fs.mode |= ModeSymlink
-	case syscall.S_IFREG:
-		// nothing to do
-	case syscall.S_IFSOCK:
-		fs.mode |= ModeSocket
-	}
-	if fs.sys.Mode&syscall.S_ISGID != 0 {
-		fs.mode |= ModeSetgid
-	}
-	if fs.sys.Mode&syscall.S_ISUID != 0 {
-		fs.mode |= ModeSetuid
-	}
-	if fs.sys.Mode&syscall.S_ISVTX != 0 {
-		fs.mode |= ModeSticky
-	}
-}
-
-func timespecToTime(ts syscall.Timespec) time.Time {
-	return time.Unix(int64(ts.Sec), int64(ts.Nsec))
-}
-
-// For testing.
-func atime(fi FileInfo) time.Time {
-	return timespecToTime(fi.Sys().(*syscall.Stat_t).Atimespec)
-}
diff --git a/contrib/go/_std_1.18/src/os/stat_linux.go b/contrib/go/_std_1.18/src/os/stat_linux.go
deleted file mode 100644
index d36afa9ffd..0000000000
--- a/contrib/go/_std_1.18/src/os/stat_linux.go
+++ /dev/null
@@ -1,51 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package os
-
-import (
-	"syscall"
-	"time"
-)
-
-func fillFileStatFromSys(fs *fileStat, name string) {
-	fs.name = basename(name)
-	fs.size = fs.sys.Size
-	fs.modTime = timespecToTime(fs.sys.Mtim)
-	fs.mode = FileMode(fs.sys.Mode & 0777)
-	switch fs.sys.Mode & syscall.S_IFMT {
-	case syscall.S_IFBLK:
-		fs.mode |= ModeDevice
-	case syscall.S_IFCHR:
-		fs.mode |= ModeDevice | ModeCharDevice
-	case syscall.S_IFDIR:
-		fs.mode |= ModeDir
-	case syscall.S_IFIFO:
-		fs.mode |= ModeNamedPipe
-	case syscall.S_IFLNK:
-		fs.mode |= ModeSymlink
-	case syscall.S_IFREG:
-		// nothing to do
-	case syscall.S_IFSOCK:
-		fs.mode |= ModeSocket
-	}
-	if fs.sys.Mode&syscall.S_ISGID != 0 {
-		fs.mode |= ModeSetgid
-	}
-	if fs.sys.Mode&syscall.S_ISUID != 0 {
-		fs.mode |= ModeSetuid
-	}
-	if fs.sys.Mode&syscall.S_ISVTX != 0 {
-		fs.mode |= ModeSticky
-	}
-}
-
-func timespecToTime(ts syscall.Timespec) time.Time {
-	return time.Unix(int64(ts.Sec), int64(ts.Nsec))
-}
-
-// For testing.
-func atime(fi FileInfo) time.Time {
-	return timespecToTime(fi.Sys().(*syscall.Stat_t).Atim)
-}
diff --git a/contrib/go/_std_1.18/src/os/stat_unix.go b/contrib/go/_std_1.18/src/os/stat_unix.go
deleted file mode 100644
index eb15db5453..0000000000
--- a/contrib/go/_std_1.18/src/os/stat_unix.go
+++ /dev/null
@@ -1,52 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris
-
-package os
-
-import (
-	"syscall"
-)
-
-// Stat returns the FileInfo structure describing file.
-// If there is an error, it will be of type *PathError.
-func (f *File) Stat() (FileInfo, error) {
-	if f == nil {
-		return nil, ErrInvalid
-	}
-	var fs fileStat
-	err := f.pfd.Fstat(&fs.sys)
-	if err != nil {
-		return nil, &PathError{Op: "stat", Path: f.name, Err: err}
-	}
-	fillFileStatFromSys(&fs, f.name)
-	return &fs, nil
-}
-
-// statNolog stats a file with no test logging.
-func statNolog(name string) (FileInfo, error) {
-	var fs fileStat
-	err := ignoringEINTR(func() error {
-		return syscall.Stat(name, &fs.sys)
-	})
-	if err != nil {
-		return nil, &PathError{Op: "stat", Path: name, Err: err}
-	}
-	fillFileStatFromSys(&fs, name)
-	return &fs, nil
-}
-
-// lstatNolog lstats a file with no test logging.
-func lstatNolog(name string) (FileInfo, error) {
-	var fs fileStat
-	err := ignoringEINTR(func() error {
-		return syscall.Lstat(name, &fs.sys)
-	})
-	if err != nil {
-		return nil, &PathError{Op: "lstat", Path: name, Err: err}
-	}
-	fillFileStatFromSys(&fs, name)
-	return &fs, nil
-}
diff --git a/contrib/go/_std_1.18/src/os/sys_unix.go b/contrib/go/_std_1.18/src/os/sys_unix.go
deleted file mode 100644
index 5ff39780e5..0000000000
--- a/contrib/go/_std_1.18/src/os/sys_unix.go
+++ /dev/null
@@ -1,14 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
-
-package os
-
-// supportsCloseOnExec reports whether the platform supports the
-// O_CLOEXEC flag.
-// On Darwin, the O_CLOEXEC flag was introduced in OS X 10.7 (Darwin 11.0.0).
-// See https://support.apple.com/kb/HT1633.
-// On FreeBSD, the O_CLOEXEC flag was introduced in version 8.3.
-const supportsCloseOnExec = true
diff --git a/contrib/go/_std_1.18/src/path/filepath/match.go b/contrib/go/_std_1.18/src/path/filepath/match.go
deleted file mode 100644
index 55ed1d75ae..0000000000
--- a/contrib/go/_std_1.18/src/path/filepath/match.go
+++ /dev/null
@@ -1,370 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package filepath
-
-import (
-	"errors"
-	"os"
-	"runtime"
-	"sort"
-	"strings"
-	"unicode/utf8"
-)
-
-// ErrBadPattern indicates a pattern was malformed.
-var ErrBadPattern = errors.New("syntax error in pattern")
-
-// Match reports whether name matches the shell file name pattern.
-// The pattern syntax is:
-//
-//	pattern:
-//		{ term }
-//	term:
-//		'*'         matches any sequence of non-Separator characters
-//		'?'         matches any single non-Separator character
-//		'[' [ '^' ] { character-range } ']'
-//		            character class (must be non-empty)
-//		c           matches character c (c != '*', '?', '\\', '[')
-//		'\\' c      matches character c
-//
-//	character-range:
-//		c           matches character c (c != '\\', '-', ']')
-//		'\\' c      matches character c
-//		lo '-' hi   matches character c for lo <= c <= hi
-//
-// Match requires pattern to match all of name, not just a substring.
-// The only possible returned error is ErrBadPattern, when pattern
-// is malformed.
-//
-// On Windows, escaping is disabled. Instead, '\\' is treated as
-// path separator.
-//
-func Match(pattern, name string) (matched bool, err error) {
-Pattern:
-	for len(pattern) > 0 {
-		var star bool
-		var chunk string
-		star, chunk, pattern = scanChunk(pattern)
-		if star && chunk == "" {
-			// Trailing * matches rest of string unless it has a /.
-			return !strings.Contains(name, string(Separator)), nil
-		}
-		// Look for match at current position.
-		t, ok, err := matchChunk(chunk, name)
-		// if we're the last chunk, make sure we've exhausted the name
-		// otherwise we'll give a false result even if we could still match
-		// using the star
-		if ok && (len(t) == 0 || len(pattern) > 0) {
-			name = t
-			continue
-		}
-		if err != nil {
-			return false, err
-		}
-		if star {
-			// Look for match skipping i+1 bytes.
-			// Cannot skip /.
-			for i := 0; i < len(name) && name[i] != Separator; i++ {
-				t, ok, err := matchChunk(chunk, name[i+1:])
-				if ok {
-					// if we're the last chunk, make sure we exhausted the name
-					if len(pattern) == 0 && len(t) > 0 {
-						continue
-					}
-					name = t
-					continue Pattern
-				}
-				if err != nil {
-					return false, err
-				}
-			}
-		}
-		return false, nil
-	}
-	return len(name) == 0, nil
-}
-
-// scanChunk gets the next segment of pattern, which is a non-star string
-// possibly preceded by a star.
-func scanChunk(pattern string) (star bool, chunk, rest string) {
-	for len(pattern) > 0 && pattern[0] == '*' {
-		pattern = pattern[1:]
-		star = true
-	}
-	inrange := false
-	var i int
-Scan:
-	for i = 0; i < len(pattern); i++ {
-		switch pattern[i] {
-		case '\\':
-			if runtime.GOOS != "windows" {
-				// error check handled in matchChunk: bad pattern.
-				if i+1 < len(pattern) {
-					i++
-				}
-			}
-		case '[':
-			inrange = true
-		case ']':
-			inrange = false
-		case '*':
-			if !inrange {
-				break Scan
-			}
-		}
-	}
-	return star, pattern[0:i], pattern[i:]
-}
-
-// matchChunk checks whether chunk matches the beginning of s.
-// If so, it returns the remainder of s (after the match).
-// Chunk is all single-character operators: literals, char classes, and ?.
-func matchChunk(chunk, s string) (rest string, ok bool, err error) {
-	// failed records whether the match has failed.
-	// After the match fails, the loop continues on processing chunk,
-	// checking that the pattern is well-formed but no longer reading s.
-	failed := false
-	for len(chunk) > 0 {
-		if !failed && len(s) == 0 {
-			failed = true
-		}
-		switch chunk[0] {
-		case '[':
-			// character class
-			var r rune
-			if !failed {
-				var n int
-				r, n = utf8.DecodeRuneInString(s)
-				s = s[n:]
-			}
-			chunk = chunk[1:]
-			// possibly negated
-			negated := false
-			if len(chunk) > 0 && chunk[0] == '^' {
-				negated = true
-				chunk = chunk[1:]
-			}
-			// parse all ranges
-			match := false
-			nrange := 0
-			for {
-				if len(chunk) > 0 && chunk[0] == ']' && nrange > 0 {
-					chunk = chunk[1:]
-					break
-				}
-				var lo, hi rune
-				if lo, chunk, err = getEsc(chunk); err != nil {
-					return "", false, err
-				}
-				hi = lo
-				if chunk[0] == '-' {
-					if hi, chunk, err = getEsc(chunk[1:]); err != nil {
-						return "", false, err
-					}
-				}
-				if lo <= r && r <= hi {
-					match = true
-				}
-				nrange++
-			}
-			if match == negated {
-				failed = true
-			}
-
-		case '?':
-			if !failed {
-				if s[0] == Separator {
-					failed = true
-				}
-				_, n := utf8.DecodeRuneInString(s)
-				s = s[n:]
-			}
-			chunk = chunk[1:]
-
-		case '\\':
-			if runtime.GOOS != "windows" {
-				chunk = chunk[1:]
-				if len(chunk) == 0 {
-					return "", false, ErrBadPattern
-				}
-			}
-			fallthrough
-
-		default:
-			if !failed {
-				if chunk[0] != s[0] {
-					failed = true
-				}
-				s = s[1:]
-			}
-			chunk = chunk[1:]
-		}
-	}
-	if failed {
-		return "", false, nil
-	}
-	return s, true, nil
-}
-
-// getEsc gets a possibly-escaped character from chunk, for a character class.
-func getEsc(chunk string) (r rune, nchunk string, err error) {
-	if len(chunk) == 0 || chunk[0] == '-' || chunk[0] == ']' {
-		err = ErrBadPattern
-		return
-	}
-	if chunk[0] == '\\' && runtime.GOOS != "windows" {
-		chunk = chunk[1:]
-		if len(chunk) == 0 {
-			err = ErrBadPattern
-			return
-		}
-	}
-	r, n := utf8.DecodeRuneInString(chunk)
-	if r == utf8.RuneError && n == 1 {
-		err = ErrBadPattern
-	}
-	nchunk = chunk[n:]
-	if len(nchunk) == 0 {
-		err = ErrBadPattern
-	}
-	return
-}
-
-// Glob returns the names of all files matching pattern or nil
-// if there is no matching file. The syntax of patterns is the same
-// as in Match. The pattern may describe hierarchical names such as
-// /usr/*/bin/ed (assuming the Separator is '/').
-//
-// Glob ignores file system errors such as I/O errors reading directories.
-// The only possible returned error is ErrBadPattern, when pattern
-// is malformed.
-func Glob(pattern string) (matches []string, err error) {
-	return globWithLimit(pattern, 0)
-}
-
-func globWithLimit(pattern string, depth int) (matches []string, err error) {
-	// This limit is used prevent stack exhaustion issues. See CVE-2022-30632.
-	const pathSeparatorsLimit = 10000
-	if depth == pathSeparatorsLimit {
-		return nil, ErrBadPattern
-	}
-
-	// Check pattern is well-formed.
-	if _, err := Match(pattern, ""); err != nil {
-		return nil, err
-	}
-	if !hasMeta(pattern) {
-		if _, err = os.Lstat(pattern); err != nil {
-			return nil, nil
-		}
-		return []string{pattern}, nil
-	}
-
-	dir, file := Split(pattern)
-	volumeLen := 0
-	if runtime.GOOS == "windows" {
-		volumeLen, dir = cleanGlobPathWindows(dir)
-	} else {
-		dir = cleanGlobPath(dir)
-	}
-
-	if !hasMeta(dir[volumeLen:]) {
-		return glob(dir, file, nil)
-	}
-
-	// Prevent infinite recursion. See issue 15879.
-	if dir == pattern {
-		return nil, ErrBadPattern
-	}
-
-	var m []string
-	m, err = globWithLimit(dir, depth+1)
-	if err != nil {
-		return
-	}
-	for _, d := range m {
-		matches, err = glob(d, file, matches)
-		if err != nil {
-			return
-		}
-	}
-	return
-}
-
-// cleanGlobPath prepares path for glob matching.
-func cleanGlobPath(path string) string {
-	switch path {
-	case "":
-		return "."
-	case string(Separator):
-		// do nothing to the path
-		return path
-	default:
-		return path[0 : len(path)-1] // chop off trailing separator
-	}
-}
-
-// cleanGlobPathWindows is windows version of cleanGlobPath.
-func cleanGlobPathWindows(path string) (prefixLen int, cleaned string) {
-	vollen := volumeNameLen(path)
-	switch {
-	case path == "":
-		return 0, "."
-	case vollen+1 == len(path) && os.IsPathSeparator(path[len(path)-1]): // /, \, C:\ and C:/
-		// do nothing to the path
-		return vollen + 1, path
-	case vollen == len(path) && len(path) == 2: // C:
-		return vollen, path + "." // convert C: into C:.
-	default:
-		if vollen >= len(path) {
-			vollen = len(path) - 1
-		}
-		return vollen, path[0 : len(path)-1] // chop off trailing separator
-	}
-}
-
-// glob searches for files matching pattern in the directory dir
-// and appends them to matches. If the directory cannot be
-// opened, it returns the existing matches. New matches are
-// added in lexicographical order.
-func glob(dir, pattern string, matches []string) (m []string, e error) {
-	m = matches
-	fi, err := os.Stat(dir)
-	if err != nil {
-		return // ignore I/O error
-	}
-	if !fi.IsDir() {
-		return // ignore I/O error
-	}
-	d, err := os.Open(dir)
-	if err != nil {
-		return // ignore I/O error
-	}
-	defer d.Close()
-
-	names, _ := d.Readdirnames(-1)
-	sort.Strings(names)
-
-	for _, n := range names {
-		matched, err := Match(pattern, n)
-		if err != nil {
-			return m, err
-		}
-		if matched {
-			m = append(m, Join(dir, n))
-		}
-	}
-	return
-}
-
-// hasMeta reports whether path contains any of the magic characters
-// recognized by Match.
-func hasMeta(path string) bool {
-	magicChars := `*?[`
-	if runtime.GOOS != "windows" {
-		magicChars = `*?[\`
-	}
-	return strings.ContainsAny(path, magicChars)
-}
diff --git a/contrib/go/_std_1.18/src/path/filepath/path.go b/contrib/go/_std_1.18/src/path/filepath/path.go
deleted file mode 100644
index 8300a32cb1..0000000000
--- a/contrib/go/_std_1.18/src/path/filepath/path.go
+++ /dev/null
@@ -1,612 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package filepath implements utility routines for manipulating filename paths
-// in a way compatible with the target operating system-defined file paths.
-//
-// The filepath package uses either forward slashes or backslashes,
-// depending on the operating system. To process paths such as URLs
-// that always use forward slashes regardless of the operating
-// system, see the path package.
-package filepath
-
-import (
-	"errors"
-	"io/fs"
-	"os"
-	"sort"
-	"strings"
-)
-
-// A lazybuf is a lazily constructed path buffer.
-// It supports append, reading previously appended bytes,
-// and retrieving the final string. It does not allocate a buffer
-// to hold the output until that output diverges from s.
-type lazybuf struct {
-	path       string
-	buf        []byte
-	w          int
-	volAndPath string
-	volLen     int
-}
-
-func (b *lazybuf) index(i int) byte {
-	if b.buf != nil {
-		return b.buf[i]
-	}
-	return b.path[i]
-}
-
-func (b *lazybuf) append(c byte) {
-	if b.buf == nil {
-		if b.w < len(b.path) && b.path[b.w] == c {
-			b.w++
-			return
-		}
-		b.buf = make([]byte, len(b.path))
-		copy(b.buf, b.path[:b.w])
-	}
-	b.buf[b.w] = c
-	b.w++
-}
-
-func (b *lazybuf) string() string {
-	if b.buf == nil {
-		return b.volAndPath[:b.volLen+b.w]
-	}
-	return b.volAndPath[:b.volLen] + string(b.buf[:b.w])
-}
-
-const (
-	Separator     = os.PathSeparator
-	ListSeparator = os.PathListSeparator
-)
-
-// Clean returns the shortest path name equivalent to path
-// by purely lexical processing. It applies the following rules
-// iteratively until no further processing can be done:
-//
-//	1. Replace multiple Separator elements with a single one.
-//	2. Eliminate each . path name element (the current directory).
-//	3. Eliminate each inner .. path name element (the parent directory)
-//	   along with the non-.. element that precedes it.
-//	4. Eliminate .. elements that begin a rooted path:
-//	   that is, replace "/.." by "/" at the beginning of a path,
-//	   assuming Separator is '/'.
-//
-// The returned path ends in a slash only if it represents a root directory,
-// such as "/" on Unix or `C:\` on Windows.
-//
-// Finally, any occurrences of slash are replaced by Separator.
-//
-// If the result of this process is an empty string, Clean
-// returns the string ".".
-//
-// See also Rob Pike, ``Lexical File Names in Plan 9 or
-// Getting Dot-Dot Right,''
-// https://9p.io/sys/doc/lexnames.html
-func Clean(path string) string {
-	originalPath := path
-	volLen := volumeNameLen(path)
-	path = path[volLen:]
-	if path == "" {
-		if volLen > 1 && originalPath[1] != ':' {
-			// should be UNC
-			return FromSlash(originalPath)
-		}
-		return originalPath + "."
-	}
-	rooted := os.IsPathSeparator(path[0])
-
-	// Invariants:
-	//	reading from path; r is index of next byte to process.
-	//	writing to buf; w is index of next byte to write.
-	//	dotdot is index in buf where .. must stop, either because
-	//		it is the leading slash or it is a leading ../../.. prefix.
-	n := len(path)
-	out := lazybuf{path: path, volAndPath: originalPath, volLen: volLen}
-	r, dotdot := 0, 0
-	if rooted {
-		out.append(Separator)
-		r, dotdot = 1, 1
-	}
-
-	for r < n {
-		switch {
-		case os.IsPathSeparator(path[r]):
-			// empty path element
-			r++
-		case path[r] == '.' && r+1 == n:
-			// . element
-			r++
-		case path[r] == '.' && os.IsPathSeparator(path[r+1]):
-			// ./ element
-			r++
-
-			for r < len(path) && os.IsPathSeparator(path[r]) {
-				r++
-			}
-			if out.w == 0 && volumeNameLen(path[r:]) > 0 {
-				// When joining prefix "." and an absolute path on Windows,
-				// the prefix should not be removed.
-				out.append('.')
-			}
-		case path[r] == '.' && path[r+1] == '.' && (r+2 == n || os.IsPathSeparator(path[r+2])):
-			// .. element: remove to last separator
-			r += 2
-			switch {
-			case out.w > dotdot:
-				// can backtrack
-				out.w--
-				for out.w > dotdot && !os.IsPathSeparator(out.index(out.w)) {
-					out.w--
-				}
-			case !rooted:
-				// cannot backtrack, but not rooted, so append .. element.
-				if out.w > 0 {
-					out.append(Separator)
-				}
-				out.append('.')
-				out.append('.')
-				dotdot = out.w
-			}
-		default:
-			// real path element.
-			// add slash if needed
-			if rooted && out.w != 1 || !rooted && out.w != 0 {
-				out.append(Separator)
-			}
-			// copy element
-			for ; r < n && !os.IsPathSeparator(path[r]); r++ {
-				out.append(path[r])
-			}
-		}
-	}
-
-	// Turn empty string into "."
-	if out.w == 0 {
-		out.append('.')
-	}
-
-	return FromSlash(out.string())
-}
-
-// ToSlash returns the result of replacing each separator character
-// in path with a slash ('/') character. Multiple separators are
-// replaced by multiple slashes.
-func ToSlash(path string) string {
-	if Separator == '/' {
-		return path
-	}
-	return strings.ReplaceAll(path, string(Separator), "/")
-}
-
-// FromSlash returns the result of replacing each slash ('/') character
-// in path with a separator character. Multiple slashes are replaced
-// by multiple separators.
-func FromSlash(path string) string {
-	if Separator == '/' {
-		return path
-	}
-	return strings.ReplaceAll(path, "/", string(Separator))
-}
-
-// SplitList splits a list of paths joined by the OS-specific ListSeparator,
-// usually found in PATH or GOPATH environment variables.
-// Unlike strings.Split, SplitList returns an empty slice when passed an empty
-// string.
-func SplitList(path string) []string {
-	return splitList(path)
-}
-
-// Split splits path immediately following the final Separator,
-// separating it into a directory and file name component.
-// If there is no Separator in path, Split returns an empty dir
-// and file set to path.
-// The returned values have the property that path = dir+file.
-func Split(path string) (dir, file string) {
-	vol := VolumeName(path)
-	i := len(path) - 1
-	for i >= len(vol) && !os.IsPathSeparator(path[i]) {
-		i--
-	}
-	return path[:i+1], path[i+1:]
-}
-
-// Join joins any number of path elements into a single path,
-// separating them with an OS specific Separator. Empty elements
-// are ignored. The result is Cleaned. However, if the argument
-// list is empty or all its elements are empty, Join returns
-// an empty string.
-// On Windows, the result will only be a UNC path if the first
-// non-empty element is a UNC path.
-func Join(elem ...string) string {
-	return join(elem)
-}
-
-// Ext returns the file name extension used by path.
-// The extension is the suffix beginning at the final dot
-// in the final element of path; it is empty if there is
-// no dot.
-func Ext(path string) string {
-	for i := len(path) - 1; i >= 0 && !os.IsPathSeparator(path[i]); i-- {
-		if path[i] == '.' {
-			return path[i:]
-		}
-	}
-	return ""
-}
-
-// EvalSymlinks returns the path name after the evaluation of any symbolic
-// links.
-// If path is relative the result will be relative to the current directory,
-// unless one of the components is an absolute symbolic link.
-// EvalSymlinks calls Clean on the result.
-func EvalSymlinks(path string) (string, error) {
-	return evalSymlinks(path)
-}
-
-// Abs returns an absolute representation of path.
-// If the path is not absolute it will be joined with the current
-// working directory to turn it into an absolute path. The absolute
-// path name for a given file is not guaranteed to be unique.
-// Abs calls Clean on the result.
-func Abs(path string) (string, error) {
-	return abs(path)
-}
-
-func unixAbs(path string) (string, error) {
-	if IsAbs(path) {
-		return Clean(path), nil
-	}
-	wd, err := os.Getwd()
-	if err != nil {
-		return "", err
-	}
-	return Join(wd, path), nil
-}
-
-// Rel returns a relative path that is lexically equivalent to targpath when
-// joined to basepath with an intervening separator. That is,
-// Join(basepath, Rel(basepath, targpath)) is equivalent to targpath itself.
-// On success, the returned path will always be relative to basepath,
-// even if basepath and targpath share no elements.
-// An error is returned if targpath can't be made relative to basepath or if
-// knowing the current working directory would be necessary to compute it.
-// Rel calls Clean on the result.
-func Rel(basepath, targpath string) (string, error) {
-	baseVol := VolumeName(basepath)
-	targVol := VolumeName(targpath)
-	base := Clean(basepath)
-	targ := Clean(targpath)
-	if sameWord(targ, base) {
-		return ".", nil
-	}
-	base = base[len(baseVol):]
-	targ = targ[len(targVol):]
-	if base == "." {
-		base = ""
-	} else if base == "" && volumeNameLen(baseVol) > 2 /* isUNC */ {
-		// Treat any targetpath matching `\\host\share` basepath as absolute path.
-		base = string(Separator)
-	}
-
-	// Can't use IsAbs - `\a` and `a` are both relative in Windows.
-	baseSlashed := len(base) > 0 && base[0] == Separator
-	targSlashed := len(targ) > 0 && targ[0] == Separator
-	if baseSlashed != targSlashed || !sameWord(baseVol, targVol) {
-		return "", errors.New("Rel: can't make " + targpath + " relative to " + basepath)
-	}
-	// Position base[b0:bi] and targ[t0:ti] at the first differing elements.
-	bl := len(base)
-	tl := len(targ)
-	var b0, bi, t0, ti int
-	for {
-		for bi < bl && base[bi] != Separator {
-			bi++
-		}
-		for ti < tl && targ[ti] != Separator {
-			ti++
-		}
-		if !sameWord(targ[t0:ti], base[b0:bi]) {
-			break
-		}
-		if bi < bl {
-			bi++
-		}
-		if ti < tl {
-			ti++
-		}
-		b0 = bi
-		t0 = ti
-	}
-	if base[b0:bi] == ".." {
-		return "", errors.New("Rel: can't make " + targpath + " relative to " + basepath)
-	}
-	if b0 != bl {
-		// Base elements left. Must go up before going down.
-		seps := strings.Count(base[b0:bl], string(Separator))
-		size := 2 + seps*3
-		if tl != t0 {
-			size += 1 + tl - t0
-		}
-		buf := make([]byte, size)
-		n := copy(buf, "..")
-		for i := 0; i < seps; i++ {
-			buf[n] = Separator
-			copy(buf[n+1:], "..")
-			n += 3
-		}
-		if t0 != tl {
-			buf[n] = Separator
-			copy(buf[n+1:], targ[t0:])
-		}
-		return string(buf), nil
-	}
-	return targ[t0:], nil
-}
-
-// SkipDir is used as a return value from WalkFuncs to indicate that
-// the directory named in the call is to be skipped. It is not returned
-// as an error by any function.
-var SkipDir error = fs.SkipDir
-
-// WalkFunc is the type of the function called by Walk to visit each
-// file or directory.
-//
-// The path argument contains the argument to Walk as a prefix.
-// That is, if Walk is called with root argument "dir" and finds a file
-// named "a" in that directory, the walk function will be called with
-// argument "dir/a".
-//
-// The directory and file are joined with Join, which may clean the
-// directory name: if Walk is called with the root argument "x/../dir"
-// and finds a file named "a" in that directory, the walk function will
-// be called with argument "dir/a", not "x/../dir/a".
-//
-// The info argument is the fs.FileInfo for the named path.
-//
-// The error result returned by the function controls how Walk continues.
-// If the function returns the special value SkipDir, Walk skips the
-// current directory (path if info.IsDir() is true, otherwise path's
-// parent directory). Otherwise, if the function returns a non-nil error,
-// Walk stops entirely and returns that error.
-//
-// The err argument reports an error related to path, signaling that Walk
-// will not walk into that directory. The function can decide how to
-// handle that error; as described earlier, returning the error will
-// cause Walk to stop walking the entire tree.
-//
-// Walk calls the function with a non-nil err argument in two cases.
-//
-// First, if an os.Lstat on the root directory or any directory or file
-// in the tree fails, Walk calls the function with path set to that
-// directory or file's path, info set to nil, and err set to the error
-// from os.Lstat.
-//
-// Second, if a directory's Readdirnames method fails, Walk calls the
-// function with path set to the directory's path, info, set to an
-// fs.FileInfo describing the directory, and err set to the error from
-// Readdirnames.
-type WalkFunc func(path string, info fs.FileInfo, err error) error
-
-var lstat = os.Lstat // for testing
-
-// walkDir recursively descends path, calling walkDirFn.
-func walkDir(path string, d fs.DirEntry, walkDirFn fs.WalkDirFunc) error {
-	if err := walkDirFn(path, d, nil); err != nil || !d.IsDir() {
-		if err == SkipDir && d.IsDir() {
-			// Successfully skipped directory.
-			err = nil
-		}
-		return err
-	}
-
-	dirs, err := readDir(path)
-	if err != nil {
-		// Second call, to report ReadDir error.
-		err = walkDirFn(path, d, err)
-		if err != nil {
-			return err
-		}
-	}
-
-	for _, d1 := range dirs {
-		path1 := Join(path, d1.Name())
-		if err := walkDir(path1, d1, walkDirFn); err != nil {
-			if err == SkipDir {
-				break
-			}
-			return err
-		}
-	}
-	return nil
-}
-
-// walk recursively descends path, calling walkFn.
-func walk(path string, info fs.FileInfo, walkFn WalkFunc) error {
-	if !info.IsDir() {
-		return walkFn(path, info, nil)
-	}
-
-	names, err := readDirNames(path)
-	err1 := walkFn(path, info, err)
-	// If err != nil, walk can't walk into this directory.
-	// err1 != nil means walkFn want walk to skip this directory or stop walking.
-	// Therefore, if one of err and err1 isn't nil, walk will return.
-	if err != nil || err1 != nil {
-		// The caller's behavior is controlled by the return value, which is decided
-		// by walkFn. walkFn may ignore err and return nil.
-		// If walkFn returns SkipDir, it will be handled by the caller.
-		// So walk should return whatever walkFn returns.
-		return err1
-	}
-
-	for _, name := range names {
-		filename := Join(path, name)
-		fileInfo, err := lstat(filename)
-		if err != nil {
-			if err := walkFn(filename, fileInfo, err); err != nil && err != SkipDir {
-				return err
-			}
-		} else {
-			err = walk(filename, fileInfo, walkFn)
-			if err != nil {
-				if !fileInfo.IsDir() || err != SkipDir {
-					return err
-				}
-			}
-		}
-	}
-	return nil
-}
-
-// WalkDir walks the file tree rooted at root, calling fn for each file or
-// directory in the tree, including root.
-//
-// All errors that arise visiting files and directories are filtered by fn:
-// see the fs.WalkDirFunc documentation for details.
-//
-// The files are walked in lexical order, which makes the output deterministic
-// but requires WalkDir to read an entire directory into memory before proceeding
-// to walk that directory.
-//
-// WalkDir does not follow symbolic links.
-func WalkDir(root string, fn fs.WalkDirFunc) error {
-	info, err := os.Lstat(root)
-	if err != nil {
-		err = fn(root, nil, err)
-	} else {
-		err = walkDir(root, &statDirEntry{info}, fn)
-	}
-	if err == SkipDir {
-		return nil
-	}
-	return err
-}
-
-type statDirEntry struct {
-	info fs.FileInfo
-}
-
-func (d *statDirEntry) Name() string               { return d.info.Name() }
-func (d *statDirEntry) IsDir() bool                { return d.info.IsDir() }
-func (d *statDirEntry) Type() fs.FileMode          { return d.info.Mode().Type() }
-func (d *statDirEntry) Info() (fs.FileInfo, error) { return d.info, nil }
-
-// Walk walks the file tree rooted at root, calling fn for each file or
-// directory in the tree, including root.
-//
-// All errors that arise visiting files and directories are filtered by fn:
-// see the WalkFunc documentation for details.
-//
-// The files are walked in lexical order, which makes the output deterministic
-// but requires Walk to read an entire directory into memory before proceeding
-// to walk that directory.
-//
-// Walk does not follow symbolic links.
-//
-// Walk is less efficient than WalkDir, introduced in Go 1.16,
-// which avoids calling os.Lstat on every visited file or directory.
-func Walk(root string, fn WalkFunc) error {
-	info, err := os.Lstat(root)
-	if err != nil {
-		err = fn(root, nil, err)
-	} else {
-		err = walk(root, info, fn)
-	}
-	if err == SkipDir {
-		return nil
-	}
-	return err
-}
-
-// readDir reads the directory named by dirname and returns
-// a sorted list of directory entries.
-func readDir(dirname string) ([]fs.DirEntry, error) {
-	f, err := os.Open(dirname)
-	if err != nil {
-		return nil, err
-	}
-	dirs, err := f.ReadDir(-1)
-	f.Close()
-	if err != nil {
-		return nil, err
-	}
-	sort.Slice(dirs, func(i, j int) bool { return dirs[i].Name() < dirs[j].Name() })
-	return dirs, nil
-}
-
-// readDirNames reads the directory named by dirname and returns
-// a sorted list of directory entry names.
-func readDirNames(dirname string) ([]string, error) {
-	f, err := os.Open(dirname)
-	if err != nil {
-		return nil, err
-	}
-	names, err := f.Readdirnames(-1)
-	f.Close()
-	if err != nil {
-		return nil, err
-	}
-	sort.Strings(names)
-	return names, nil
-}
-
-// Base returns the last element of path.
-// Trailing path separators are removed before extracting the last element.
-// If the path is empty, Base returns ".".
-// If the path consists entirely of separators, Base returns a single separator.
-func Base(path string) string {
-	if path == "" {
-		return "."
-	}
-	// Strip trailing slashes.
-	for len(path) > 0 && os.IsPathSeparator(path[len(path)-1]) {
-		path = path[0 : len(path)-1]
-	}
-	// Throw away volume name
-	path = path[len(VolumeName(path)):]
-	// Find the last element
-	i := len(path) - 1
-	for i >= 0 && !os.IsPathSeparator(path[i]) {
-		i--
-	}
-	if i >= 0 {
-		path = path[i+1:]
-	}
-	// If empty now, it had only slashes.
-	if path == "" {
-		return string(Separator)
-	}
-	return path
-}
-
-// Dir returns all but the last element of path, typically the path's directory.
-// After dropping the final element, Dir calls Clean on the path and trailing
-// slashes are removed.
-// If the path is empty, Dir returns ".".
-// If the path consists entirely of separators, Dir returns a single separator.
-// The returned path does not end in a separator unless it is the root directory.
-func Dir(path string) string {
-	vol := VolumeName(path)
-	i := len(path) - 1
-	for i >= len(vol) && !os.IsPathSeparator(path[i]) {
-		i--
-	}
-	dir := Clean(path[len(vol) : i+1])
-	if dir == "." && len(vol) > 2 {
-		// must be UNC
-		return vol
-	}
-	return vol + dir
-}
-
-// VolumeName returns leading volume name.
-// Given "C:\foo\bar" it returns "C:" on Windows.
-// Given "\\host\share\foo" it returns "\\host\share".
-// On other platforms it returns "".
-func VolumeName(path string) string {
-	return path[:volumeNameLen(path)]
-}
diff --git a/contrib/go/_std_1.18/src/path/filepath/path_unix.go b/contrib/go/_std_1.18/src/path/filepath/path_unix.go
deleted file mode 100644
index dcf1d187e7..0000000000
--- a/contrib/go/_std_1.18/src/path/filepath/path_unix.go
+++ /dev/null
@@ -1,53 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris
-
-package filepath
-
-import "strings"
-
-// IsAbs reports whether the path is absolute.
-func IsAbs(path string) bool {
-	return strings.HasPrefix(path, "/")
-}
-
-// volumeNameLen returns length of the leading volume name on Windows.
-// It returns 0 elsewhere.
-func volumeNameLen(path string) int {
-	return 0
-}
-
-// HasPrefix exists for historical compatibility and should not be used.
-//
-// Deprecated: HasPrefix does not respect path boundaries and
-// does not ignore case when required.
-func HasPrefix(p, prefix string) bool {
-	return strings.HasPrefix(p, prefix)
-}
-
-func splitList(path string) []string {
-	if path == "" {
-		return []string{}
-	}
-	return strings.Split(path, string(ListSeparator))
-}
-
-func abs(path string) (string, error) {
-	return unixAbs(path)
-}
-
-func join(elem []string) string {
-	// If there's a bug here, fix the logic in ./path_plan9.go too.
-	for i, e := range elem {
-		if e != "" {
-			return Clean(strings.Join(elem[i:], string(Separator)))
-		}
-	}
-	return ""
-}
-
-func sameWord(a, b string) bool {
-	return a == b
-}
diff --git a/contrib/go/_std_1.18/src/path/filepath/symlink_unix.go b/contrib/go/_std_1.18/src/path/filepath/symlink_unix.go
deleted file mode 100644
index 7bfe17e2fd..0000000000
--- a/contrib/go/_std_1.18/src/path/filepath/symlink_unix.go
+++ /dev/null
@@ -1,7 +0,0 @@
-//go:build !windows
-
-package filepath
-
-func evalSymlinks(path string) (string, error) {
-	return walkSymlinks(path)
-}
diff --git a/contrib/go/_std_1.18/src/path/match.go b/contrib/go/_std_1.18/src/path/match.go
deleted file mode 100644
index 918624c60e..0000000000
--- a/contrib/go/_std_1.18/src/path/match.go
+++ /dev/null
@@ -1,231 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package path
-
-import (
-	"errors"
-	"internal/bytealg"
-	"unicode/utf8"
-)
-
-// ErrBadPattern indicates a pattern was malformed.
-var ErrBadPattern = errors.New("syntax error in pattern")
-
-// Match reports whether name matches the shell pattern.
-// The pattern syntax is:
-//
-//	pattern:
-//		{ term }
-//	term:
-//		'*'         matches any sequence of non-/ characters
-//		'?'         matches any single non-/ character
-//		'[' [ '^' ] { character-range } ']'
-//		            character class (must be non-empty)
-//		c           matches character c (c != '*', '?', '\\', '[')
-//		'\\' c      matches character c
-//
-//	character-range:
-//		c           matches character c (c != '\\', '-', ']')
-//		'\\' c      matches character c
-//		lo '-' hi   matches character c for lo <= c <= hi
-//
-// Match requires pattern to match all of name, not just a substring.
-// The only possible returned error is ErrBadPattern, when pattern
-// is malformed.
-//
-func Match(pattern, name string) (matched bool, err error) {
-Pattern:
-	for len(pattern) > 0 {
-		var star bool
-		var chunk string
-		star, chunk, pattern = scanChunk(pattern)
-		if star && chunk == "" {
-			// Trailing * matches rest of string unless it has a /.
-			return bytealg.IndexByteString(name, '/') < 0, nil
-		}
-		// Look for match at current position.
-		t, ok, err := matchChunk(chunk, name)
-		// if we're the last chunk, make sure we've exhausted the name
-		// otherwise we'll give a false result even if we could still match
-		// using the star
-		if ok && (len(t) == 0 || len(pattern) > 0) {
-			name = t
-			continue
-		}
-		if err != nil {
-			return false, err
-		}
-		if star {
-			// Look for match skipping i+1 bytes.
-			// Cannot skip /.
-			for i := 0; i < len(name) && name[i] != '/'; i++ {
-				t, ok, err := matchChunk(chunk, name[i+1:])
-				if ok {
-					// if we're the last chunk, make sure we exhausted the name
-					if len(pattern) == 0 && len(t) > 0 {
-						continue
-					}
-					name = t
-					continue Pattern
-				}
-				if err != nil {
-					return false, err
-				}
-			}
-		}
-		// Before returning false with no error,
-		// check that the remainder of the pattern is syntactically valid.
-		for len(pattern) > 0 {
-			_, chunk, pattern = scanChunk(pattern)
-			if _, _, err := matchChunk(chunk, ""); err != nil {
-				return false, err
-			}
-		}
-		return false, nil
-	}
-	return len(name) == 0, nil
-}
-
-// scanChunk gets the next segment of pattern, which is a non-star string
-// possibly preceded by a star.
-func scanChunk(pattern string) (star bool, chunk, rest string) {
-	for len(pattern) > 0 && pattern[0] == '*' {
-		pattern = pattern[1:]
-		star = true
-	}
-	inrange := false
-	var i int
-Scan:
-	for i = 0; i < len(pattern); i++ {
-		switch pattern[i] {
-		case '\\':
-			// error check handled in matchChunk: bad pattern.
-			if i+1 < len(pattern) {
-				i++
-			}
-		case '[':
-			inrange = true
-		case ']':
-			inrange = false
-		case '*':
-			if !inrange {
-				break Scan
-			}
-		}
-	}
-	return star, pattern[0:i], pattern[i:]
-}
-
-// matchChunk checks whether chunk matches the beginning of s.
-// If so, it returns the remainder of s (after the match).
-// Chunk is all single-character operators: literals, char classes, and ?.
-func matchChunk(chunk, s string) (rest string, ok bool, err error) {
-	// failed records whether the match has failed.
-	// After the match fails, the loop continues on processing chunk,
-	// checking that the pattern is well-formed but no longer reading s.
-	failed := false
-	for len(chunk) > 0 {
-		if !failed && len(s) == 0 {
-			failed = true
-		}
-		switch chunk[0] {
-		case '[':
-			// character class
-			var r rune
-			if !failed {
-				var n int
-				r, n = utf8.DecodeRuneInString(s)
-				s = s[n:]
-			}
-			chunk = chunk[1:]
-			// possibly negated
-			negated := false
-			if len(chunk) > 0 && chunk[0] == '^' {
-				negated = true
-				chunk = chunk[1:]
-			}
-			// parse all ranges
-			match := false
-			nrange := 0
-			for {
-				if len(chunk) > 0 && chunk[0] == ']' && nrange > 0 {
-					chunk = chunk[1:]
-					break
-				}
-				var lo, hi rune
-				if lo, chunk, err = getEsc(chunk); err != nil {
-					return "", false, err
-				}
-				hi = lo
-				if chunk[0] == '-' {
-					if hi, chunk, err = getEsc(chunk[1:]); err != nil {
-						return "", false, err
-					}
-				}
-				if lo <= r && r <= hi {
-					match = true
-				}
-				nrange++
-			}
-			if match == negated {
-				failed = true
-			}
-
-		case '?':
-			if !failed {
-				if s[0] == '/' {
-					failed = true
-				}
-				_, n := utf8.DecodeRuneInString(s)
-				s = s[n:]
-			}
-			chunk = chunk[1:]
-
-		case '\\':
-			chunk = chunk[1:]
-			if len(chunk) == 0 {
-				return "", false, ErrBadPattern
-			}
-			fallthrough
-
-		default:
-			if !failed {
-				if chunk[0] != s[0] {
-					failed = true
-				}
-				s = s[1:]
-			}
-			chunk = chunk[1:]
-		}
-	}
-	if failed {
-		return "", false, nil
-	}
-	return s, true, nil
-}
-
-// getEsc gets a possibly-escaped character from chunk, for a character class.
-func getEsc(chunk string) (r rune, nchunk string, err error) {
-	if len(chunk) == 0 || chunk[0] == '-' || chunk[0] == ']' {
-		err = ErrBadPattern
-		return
-	}
-	if chunk[0] == '\\' {
-		chunk = chunk[1:]
-		if len(chunk) == 0 {
-			err = ErrBadPattern
-			return
-		}
-	}
-	r, n := utf8.DecodeRuneInString(chunk)
-	if r == utf8.RuneError && n == 1 {
-		err = ErrBadPattern
-	}
-	nchunk = chunk[n:]
-	if len(nchunk) == 0 {
-		err = ErrBadPattern
-	}
-	return
-}
diff --git a/contrib/go/_std_1.18/src/path/path.go b/contrib/go/_std_1.18/src/path/path.go
deleted file mode 100644
index f1f3499f63..0000000000
--- a/contrib/go/_std_1.18/src/path/path.go
+++ /dev/null
@@ -1,233 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package path implements utility routines for manipulating slash-separated
-// paths.
-//
-// The path package should only be used for paths separated by forward
-// slashes, such as the paths in URLs. This package does not deal with
-// Windows paths with drive letters or backslashes; to manipulate
-// operating system paths, use the path/filepath package.
-package path
-
-// A lazybuf is a lazily constructed path buffer.
-// It supports append, reading previously appended bytes,
-// and retrieving the final string. It does not allocate a buffer
-// to hold the output until that output diverges from s.
-type lazybuf struct {
-	s   string
-	buf []byte
-	w   int
-}
-
-func (b *lazybuf) index(i int) byte {
-	if b.buf != nil {
-		return b.buf[i]
-	}
-	return b.s[i]
-}
-
-func (b *lazybuf) append(c byte) {
-	if b.buf == nil {
-		if b.w < len(b.s) && b.s[b.w] == c {
-			b.w++
-			return
-		}
-		b.buf = make([]byte, len(b.s))
-		copy(b.buf, b.s[:b.w])
-	}
-	b.buf[b.w] = c
-	b.w++
-}
-
-func (b *lazybuf) string() string {
-	if b.buf == nil {
-		return b.s[:b.w]
-	}
-	return string(b.buf[:b.w])
-}
-
-// Clean returns the shortest path name equivalent to path
-// by purely lexical processing. It applies the following rules
-// iteratively until no further processing can be done:
-//
-//	1. Replace multiple slashes with a single slash.
-//	2. Eliminate each . path name element (the current directory).
-//	3. Eliminate each inner .. path name element (the parent directory)
-//	   along with the non-.. element that precedes it.
-//	4. Eliminate .. elements that begin a rooted path:
-//	   that is, replace "/.." by "/" at the beginning of a path.
-//
-// The returned path ends in a slash only if it is the root "/".
-//
-// If the result of this process is an empty string, Clean
-// returns the string ".".
-//
-// See also Rob Pike, ``Lexical File Names in Plan 9 or
-// Getting Dot-Dot Right,''
-// https://9p.io/sys/doc/lexnames.html
-func Clean(path string) string {
-	if path == "" {
-		return "."
-	}
-
-	rooted := path[0] == '/'
-	n := len(path)
-
-	// Invariants:
-	//	reading from path; r is index of next byte to process.
-	//	writing to buf; w is index of next byte to write.
-	//	dotdot is index in buf where .. must stop, either because
-	//		it is the leading slash or it is a leading ../../.. prefix.
-	out := lazybuf{s: path}
-	r, dotdot := 0, 0
-	if rooted {
-		out.append('/')
-		r, dotdot = 1, 1
-	}
-
-	for r < n {
-		switch {
-		case path[r] == '/':
-			// empty path element
-			r++
-		case path[r] == '.' && (r+1 == n || path[r+1] == '/'):
-			// . element
-			r++
-		case path[r] == '.' && path[r+1] == '.' && (r+2 == n || path[r+2] == '/'):
-			// .. element: remove to last /
-			r += 2
-			switch {
-			case out.w > dotdot:
-				// can backtrack
-				out.w--
-				for out.w > dotdot && out.index(out.w) != '/' {
-					out.w--
-				}
-			case !rooted:
-				// cannot backtrack, but not rooted, so append .. element.
-				if out.w > 0 {
-					out.append('/')
-				}
-				out.append('.')
-				out.append('.')
-				dotdot = out.w
-			}
-		default:
-			// real path element.
-			// add slash if needed
-			if rooted && out.w != 1 || !rooted && out.w != 0 {
-				out.append('/')
-			}
-			// copy element
-			for ; r < n && path[r] != '/'; r++ {
-				out.append(path[r])
-			}
-		}
-	}
-
-	// Turn empty string into "."
-	if out.w == 0 {
-		return "."
-	}
-
-	return out.string()
-}
-
-// lastSlash(s) is strings.LastIndex(s, "/") but we can't import strings.
-func lastSlash(s string) int {
-	i := len(s) - 1
-	for i >= 0 && s[i] != '/' {
-		i--
-	}
-	return i
-}
-
-// Split splits path immediately following the final slash,
-// separating it into a directory and file name component.
-// If there is no slash in path, Split returns an empty dir and
-// file set to path.
-// The returned values have the property that path = dir+file.
-func Split(path string) (dir, file string) {
-	i := lastSlash(path)
-	return path[:i+1], path[i+1:]
-}
-
-// Join joins any number of path elements into a single path,
-// separating them with slashes. Empty elements are ignored.
-// The result is Cleaned. However, if the argument list is
-// empty or all its elements are empty, Join returns
-// an empty string.
-func Join(elem ...string) string {
-	size := 0
-	for _, e := range elem {
-		size += len(e)
-	}
-	if size == 0 {
-		return ""
-	}
-	buf := make([]byte, 0, size+len(elem)-1)
-	for _, e := range elem {
-		if len(buf) > 0 || e != "" {
-			if len(buf) > 0 {
-				buf = append(buf, '/')
-			}
-			buf = append(buf, e...)
-		}
-	}
-	return Clean(string(buf))
-}
-
-// Ext returns the file name extension used by path.
-// The extension is the suffix beginning at the final dot
-// in the final slash-separated element of path;
-// it is empty if there is no dot.
-func Ext(path string) string {
-	for i := len(path) - 1; i >= 0 && path[i] != '/'; i-- {
-		if path[i] == '.' {
-			return path[i:]
-		}
-	}
-	return ""
-}
-
-// Base returns the last element of path.
-// Trailing slashes are removed before extracting the last element.
-// If the path is empty, Base returns ".".
-// If the path consists entirely of slashes, Base returns "/".
-func Base(path string) string {
-	if path == "" {
-		return "."
-	}
-	// Strip trailing slashes.
-	for len(path) > 0 && path[len(path)-1] == '/' {
-		path = path[0 : len(path)-1]
-	}
-	// Find the last element
-	if i := lastSlash(path); i >= 0 {
-		path = path[i+1:]
-	}
-	// If empty now, it had only slashes.
-	if path == "" {
-		return "/"
-	}
-	return path
-}
-
-// IsAbs reports whether the path is absolute.
-func IsAbs(path string) bool {
-	return len(path) > 0 && path[0] == '/'
-}
-
-// Dir returns all but the last element of path, typically the path's directory.
-// After dropping the final element using Split, the path is Cleaned and trailing
-// slashes are removed.
-// If the path is empty, Dir returns ".".
-// If the path consists entirely of slashes followed by non-slash bytes, Dir
-// returns a single slash. In any other case, the returned path does not end in a
-// slash.
-func Dir(path string) string {
-	dir, _ := Split(path)
-	return Clean(dir)
-}
diff --git a/contrib/go/_std_1.18/src/reflect/abi.go b/contrib/go/_std_1.18/src/reflect/abi.go
deleted file mode 100644
index 28204b8193..0000000000
--- a/contrib/go/_std_1.18/src/reflect/abi.go
+++ /dev/null
@@ -1,511 +0,0 @@
-// Copyright 2021 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package reflect
-
-import (
-	"internal/abi"
-	"internal/goarch"
-	"internal/goexperiment"
-	"unsafe"
-)
-
-// These variables are used by the register assignment
-// algorithm in this file.
-//
-// They should be modified with care (no other reflect code
-// may be executing) and are generally only modified
-// when testing this package.
-//
-// They should never be set higher than their internal/abi
-// constant counterparts, because the system relies on a
-// structure that is at least large enough to hold the
-// registers the system supports.
-//
-// Currently they're set to zero because using the actual
-// constants will break every part of the toolchain that
-// uses reflect to call functions (e.g. go test, or anything
-// that uses text/template). The values that are currently
-// commented out there should be the actual values once
-// we're ready to use the register ABI everywhere.
-var (
-	intArgRegs   = abi.IntArgRegs * goexperiment.RegabiArgsInt
-	floatArgRegs = abi.FloatArgRegs * goexperiment.RegabiArgsInt
-	floatRegSize = uintptr(abi.EffectiveFloatRegSize * goexperiment.RegabiArgsInt)
-)
-
-// abiStep represents an ABI "instruction." Each instruction
-// describes one part of how to translate between a Go value
-// in memory and a call frame.
-type abiStep struct {
-	kind abiStepKind
-
-	// offset and size together describe a part of a Go value
-	// in memory.
-	offset uintptr
-	size   uintptr // size in bytes of the part
-
-	// These fields describe the ABI side of the translation.
-	stkOff uintptr // stack offset, used if kind == abiStepStack
-	ireg   int     // integer register index, used if kind == abiStepIntReg or kind == abiStepPointer
-	freg   int     // FP register index, used if kind == abiStepFloatReg
-}
-
-// abiStepKind is the "op-code" for an abiStep instruction.
-type abiStepKind int
-
-const (
-	abiStepBad      abiStepKind = iota
-	abiStepStack                // copy to/from stack
-	abiStepIntReg               // copy to/from integer register
-	abiStepPointer              // copy pointer to/from integer register
-	abiStepFloatReg             // copy to/from FP register
-)
-
-// abiSeq represents a sequence of ABI instructions for copying
-// from a series of reflect.Values to a call frame (for call arguments)
-// or vice-versa (for call results).
-//
-// An abiSeq should be populated by calling its addArg method.
-type abiSeq struct {
-	// steps is the set of instructions.
-	//
-	// The instructions are grouped together by whole arguments,
-	// with the starting index for the instructions
-	// of the i'th Go value available in valueStart.
-	//
-	// For instance, if this abiSeq represents 3 arguments
-	// passed to a function, then the 2nd argument's steps
-	// begin at steps[valueStart[1]].
-	//
-	// Because reflect accepts Go arguments in distinct
-	// Values and each Value is stored separately, each abiStep
-	// that begins a new argument will have its offset
-	// field == 0.
-	steps      []abiStep
-	valueStart []int
-
-	stackBytes   uintptr // stack space used
-	iregs, fregs int     // registers used
-}
-
-func (a *abiSeq) dump() {
-	for i, p := range a.steps {
-		println("part", i, p.kind, p.offset, p.size, p.stkOff, p.ireg, p.freg)
-	}
-	print("values ")
-	for _, i := range a.valueStart {
-		print(i, " ")
-	}
-	println()
-	println("stack", a.stackBytes)
-	println("iregs", a.iregs)
-	println("fregs", a.fregs)
-}
-
-// stepsForValue returns the ABI instructions for translating
-// the i'th Go argument or return value represented by this
-// abiSeq to the Go ABI.
-func (a *abiSeq) stepsForValue(i int) []abiStep {
-	s := a.valueStart[i]
-	var e int
-	if i == len(a.valueStart)-1 {
-		e = len(a.steps)
-	} else {
-		e = a.valueStart[i+1]
-	}
-	return a.steps[s:e]
-}
-
-// addArg extends the abiSeq with a new Go value of type t.
-//
-// If the value was stack-assigned, returns the single
-// abiStep describing that translation, and nil otherwise.
-func (a *abiSeq) addArg(t *rtype) *abiStep {
-	// We'll always be adding a new value, so do that first.
-	pStart := len(a.steps)
-	a.valueStart = append(a.valueStart, pStart)
-	if t.size == 0 {
-		// If the size of the argument type is zero, then
-		// in order to degrade gracefully into ABI0, we need
-		// to stack-assign this type. The reason is that
-		// although zero-sized types take up no space on the
-		// stack, they do cause the next argument to be aligned.
-		// So just do that here, but don't bother actually
-		// generating a new ABI step for it (there's nothing to
-		// actually copy).
-		//
-		// We cannot handle this in the recursive case of
-		// regAssign because zero-sized *fields* of a
-		// non-zero-sized struct do not cause it to be
-		// stack-assigned. So we need a special case here
-		// at the top.
-		a.stackBytes = align(a.stackBytes, uintptr(t.align))
-		return nil
-	}
-	// Hold a copy of "a" so that we can roll back if
-	// register assignment fails.
-	aOld := *a
-	if !a.regAssign(t, 0) {
-		// Register assignment failed. Roll back any changes
-		// and stack-assign.
-		*a = aOld
-		a.stackAssign(t.size, uintptr(t.align))
-		return &a.steps[len(a.steps)-1]
-	}
-	return nil
-}
-
-// addRcvr extends the abiSeq with a new method call
-// receiver according to the interface calling convention.
-//
-// If the receiver was stack-assigned, returns the single
-// abiStep describing that translation, and nil otherwise.
-// Returns true if the receiver is a pointer.
-func (a *abiSeq) addRcvr(rcvr *rtype) (*abiStep, bool) {
-	// The receiver is always one word.
-	a.valueStart = append(a.valueStart, len(a.steps))
-	var ok, ptr bool
-	if ifaceIndir(rcvr) || rcvr.pointers() {
-		ok = a.assignIntN(0, goarch.PtrSize, 1, 0b1)
-		ptr = true
-	} else {
-		// TODO(mknyszek): Is this case even possible?
-		// The interface data work never contains a non-pointer
-		// value. This case was copied over from older code
-		// in the reflect package which only conditionally added
-		// a pointer bit to the reflect.(Value).Call stack frame's
-		// GC bitmap.
-		ok = a.assignIntN(0, goarch.PtrSize, 1, 0b0)
-		ptr = false
-	}
-	if !ok {
-		a.stackAssign(goarch.PtrSize, goarch.PtrSize)
-		return &a.steps[len(a.steps)-1], ptr
-	}
-	return nil, ptr
-}
-
-// regAssign attempts to reserve argument registers for a value of
-// type t, stored at some offset.
-//
-// It returns whether or not the assignment succeeded, but
-// leaves any changes it made to a.steps behind, so the caller
-// must undo that work by adjusting a.steps if it fails.
-//
-// This method along with the assign* methods represent the
-// complete register-assignment algorithm for the Go ABI.
-func (a *abiSeq) regAssign(t *rtype, offset uintptr) bool {
-	switch t.Kind() {
-	case UnsafePointer, Pointer, Chan, Map, Func:
-		return a.assignIntN(offset, t.size, 1, 0b1)
-	case Bool, Int, Uint, Int8, Uint8, Int16, Uint16, Int32, Uint32, Uintptr:
-		return a.assignIntN(offset, t.size, 1, 0b0)
-	case Int64, Uint64:
-		switch goarch.PtrSize {
-		case 4:
-			return a.assignIntN(offset, 4, 2, 0b0)
-		case 8:
-			return a.assignIntN(offset, 8, 1, 0b0)
-		}
-	case Float32, Float64:
-		return a.assignFloatN(offset, t.size, 1)
-	case Complex64:
-		return a.assignFloatN(offset, 4, 2)
-	case Complex128:
-		return a.assignFloatN(offset, 8, 2)
-	case String:
-		return a.assignIntN(offset, goarch.PtrSize, 2, 0b01)
-	case Interface:
-		return a.assignIntN(offset, goarch.PtrSize, 2, 0b10)
-	case Slice:
-		return a.assignIntN(offset, goarch.PtrSize, 3, 0b001)
-	case Array:
-		tt := (*arrayType)(unsafe.Pointer(t))
-		switch tt.len {
-		case 0:
-			// There's nothing to assign, so don't modify
-			// a.steps but succeed so the caller doesn't
-			// try to stack-assign this value.
-			return true
-		case 1:
-			return a.regAssign(tt.elem, offset)
-		default:
-			return false
-		}
-	case Struct:
-		st := (*structType)(unsafe.Pointer(t))
-		for i := range st.fields {
-			f := &st.fields[i]
-			if !a.regAssign(f.typ, offset+f.offset()) {
-				return false
-			}
-		}
-		return true
-	default:
-		print("t.Kind == ", t.Kind(), "\n")
-		panic("unknown type kind")
-	}
-	panic("unhandled register assignment path")
-}
-
-// assignIntN assigns n values to registers, each "size" bytes large,
-// from the data at [offset, offset+n*size) in memory. Each value at
-// [offset+i*size, offset+(i+1)*size) for i < n is assigned to the
-// next n integer registers.
-//
-// Bit i in ptrMap indicates whether the i'th value is a pointer.
-// n must be <= 8.
-//
-// Returns whether assignment succeeded.
-func (a *abiSeq) assignIntN(offset, size uintptr, n int, ptrMap uint8) bool {
-	if n > 8 || n < 0 {
-		panic("invalid n")
-	}
-	if ptrMap != 0 && size != goarch.PtrSize {
-		panic("non-empty pointer map passed for non-pointer-size values")
-	}
-	if a.iregs+n > intArgRegs {
-		return false
-	}
-	for i := 0; i < n; i++ {
-		kind := abiStepIntReg
-		if ptrMap&(uint8(1)<<i) != 0 {
-			kind = abiStepPointer
-		}
-		a.steps = append(a.steps, abiStep{
-			kind:   kind,
-			offset: offset + uintptr(i)*size,
-			size:   size,
-			ireg:   a.iregs,
-		})
-		a.iregs++
-	}
-	return true
-}
-
-// assignFloatN assigns n values to registers, each "size" bytes large,
-// from the data at [offset, offset+n*size) in memory. Each value at
-// [offset+i*size, offset+(i+1)*size) for i < n is assigned to the
-// next n floating-point registers.
-//
-// Returns whether assignment succeeded.
-func (a *abiSeq) assignFloatN(offset, size uintptr, n int) bool {
-	if n < 0 {
-		panic("invalid n")
-	}
-	if a.fregs+n > floatArgRegs || floatRegSize < size {
-		return false
-	}
-	for i := 0; i < n; i++ {
-		a.steps = append(a.steps, abiStep{
-			kind:   abiStepFloatReg,
-			offset: offset + uintptr(i)*size,
-			size:   size,
-			freg:   a.fregs,
-		})
-		a.fregs++
-	}
-	return true
-}
-
-// stackAssign reserves space for one value that is "size" bytes
-// large with alignment "alignment" to the stack.
-//
-// Should not be called directly; use addArg instead.
-func (a *abiSeq) stackAssign(size, alignment uintptr) {
-	a.stackBytes = align(a.stackBytes, alignment)
-	a.steps = append(a.steps, abiStep{
-		kind:   abiStepStack,
-		offset: 0, // Only used for whole arguments, so the memory offset is 0.
-		size:   size,
-		stkOff: a.stackBytes,
-	})
-	a.stackBytes += size
-}
-
-// abiDesc describes the ABI for a function or method.
-type abiDesc struct {
-	// call and ret represent the translation steps for
-	// the call and return paths of a Go function.
-	call, ret abiSeq
-
-	// These fields describe the stack space allocated
-	// for the call. stackCallArgsSize is the amount of space
-	// reserved for arguments but not return values. retOffset
-	// is the offset at which return values begin, and
-	// spill is the size in bytes of additional space reserved
-	// to spill argument registers into in case of preemption in
-	// reflectcall's stack frame.
-	stackCallArgsSize, retOffset, spill uintptr
-
-	// stackPtrs is a bitmap that indicates whether
-	// each word in the ABI stack space (stack-assigned
-	// args + return values) is a pointer. Used
-	// as the heap pointer bitmap for stack space
-	// passed to reflectcall.
-	stackPtrs *bitVector
-
-	// inRegPtrs is a bitmap whose i'th bit indicates
-	// whether the i'th integer argument register contains
-	// a pointer. Used by makeFuncStub and methodValueCall
-	// to make result pointers visible to the GC.
-	//
-	// outRegPtrs is the same, but for result values.
-	// Used by reflectcall to make result pointers visible
-	// to the GC.
-	inRegPtrs, outRegPtrs abi.IntArgRegBitmap
-}
-
-func (a *abiDesc) dump() {
-	println("ABI")
-	println("call")
-	a.call.dump()
-	println("ret")
-	a.ret.dump()
-	println("stackCallArgsSize", a.stackCallArgsSize)
-	println("retOffset", a.retOffset)
-	println("spill", a.spill)
-	print("inRegPtrs:")
-	dumpPtrBitMap(a.inRegPtrs)
-	println()
-	print("outRegPtrs:")
-	dumpPtrBitMap(a.outRegPtrs)
-	println()
-}
-
-func dumpPtrBitMap(b abi.IntArgRegBitmap) {
-	for i := 0; i < intArgRegs; i++ {
-		x := 0
-		if b.Get(i) {
-			x = 1
-		}
-		print(" ", x)
-	}
-}
-
-func newAbiDesc(t *funcType, rcvr *rtype) abiDesc {
-	// We need to add space for this argument to
-	// the frame so that it can spill args into it.
-	//
-	// The size of this space is just the sum of the sizes
-	// of each register-allocated type.
-	//
-	// TODO(mknyszek): Remove this when we no longer have
-	// caller reserved spill space.
-	spill := uintptr(0)
-
-	// Compute gc program & stack bitmap for stack arguments
-	stackPtrs := new(bitVector)
-
-	// Compute the stack frame pointer bitmap and register
-	// pointer bitmap for arguments.
-	inRegPtrs := abi.IntArgRegBitmap{}
-
-	// Compute abiSeq for input parameters.
-	var in abiSeq
-	if rcvr != nil {
-		stkStep, isPtr := in.addRcvr(rcvr)
-		if stkStep != nil {
-			if isPtr {
-				stackPtrs.append(1)
-			} else {
-				stackPtrs.append(0)
-			}
-		} else {
-			spill += goarch.PtrSize
-		}
-	}
-	for i, arg := range t.in() {
-		stkStep := in.addArg(arg)
-		if stkStep != nil {
-			addTypeBits(stackPtrs, stkStep.stkOff, arg)
-		} else {
-			spill = align(spill, uintptr(arg.align))
-			spill += arg.size
-			for _, st := range in.stepsForValue(i) {
-				if st.kind == abiStepPointer {
-					inRegPtrs.Set(st.ireg)
-				}
-			}
-		}
-	}
-	spill = align(spill, goarch.PtrSize)
-
-	// From the input parameters alone, we now know
-	// the stackCallArgsSize and retOffset.
-	stackCallArgsSize := in.stackBytes
-	retOffset := align(in.stackBytes, goarch.PtrSize)
-
-	// Compute the stack frame pointer bitmap and register
-	// pointer bitmap for return values.
-	outRegPtrs := abi.IntArgRegBitmap{}
-
-	// Compute abiSeq for output parameters.
-	var out abiSeq
-	// Stack-assigned return values do not share
-	// space with arguments like they do with registers,
-	// so we need to inject a stack offset here.
-	// Fake it by artificially extending stackBytes by
-	// the return offset.
-	out.stackBytes = retOffset
-	for i, res := range t.out() {
-		stkStep := out.addArg(res)
-		if stkStep != nil {
-			addTypeBits(stackPtrs, stkStep.stkOff, res)
-		} else {
-			for _, st := range out.stepsForValue(i) {
-				if st.kind == abiStepPointer {
-					outRegPtrs.Set(st.ireg)
-				}
-			}
-		}
-	}
-	// Undo the faking from earlier so that stackBytes
-	// is accurate.
-	out.stackBytes -= retOffset
-	return abiDesc{in, out, stackCallArgsSize, retOffset, spill, stackPtrs, inRegPtrs, outRegPtrs}
-}
-
-// intFromReg loads an argSize sized integer from reg and places it at to.
-//
-// argSize must be non-zero, fit in a register, and a power-of-two.
-func intFromReg(r *abi.RegArgs, reg int, argSize uintptr, to unsafe.Pointer) {
-	memmove(to, r.IntRegArgAddr(reg, argSize), argSize)
-}
-
-// intToReg loads an argSize sized integer and stores it into reg.
-//
-// argSize must be non-zero, fit in a register, and a power-of-two.
-func intToReg(r *abi.RegArgs, reg int, argSize uintptr, from unsafe.Pointer) {
-	memmove(r.IntRegArgAddr(reg, argSize), from, argSize)
-}
-
-// floatFromReg loads a float value from its register representation in r.
-//
-// argSize must be 4 or 8.
-func floatFromReg(r *abi.RegArgs, reg int, argSize uintptr, to unsafe.Pointer) {
-	switch argSize {
-	case 4:
-		*(*float32)(to) = archFloat32FromReg(r.Floats[reg])
-	case 8:
-		*(*float64)(to) = *(*float64)(unsafe.Pointer(&r.Floats[reg]))
-	default:
-		panic("bad argSize")
-	}
-}
-
-// floatToReg stores a float value in its register representation in r.
-//
-// argSize must be either 4 or 8.
-func floatToReg(r *abi.RegArgs, reg int, argSize uintptr, from unsafe.Pointer) {
-	switch argSize {
-	case 4:
-		r.Floats[reg] = archFloat32ToReg(*(*float32)(from))
-	case 8:
-		r.Floats[reg] = *(*uint64)(from)
-	default:
-		panic("bad argSize")
-	}
-}
diff --git a/contrib/go/_std_1.18/src/reflect/deepequal.go b/contrib/go/_std_1.18/src/reflect/deepequal.go
deleted file mode 100644
index eaab101221..0000000000
--- a/contrib/go/_std_1.18/src/reflect/deepequal.go
+++ /dev/null
@@ -1,238 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Deep equality test via reflection
-
-package reflect
-
-import (
-	"internal/bytealg"
-	"unsafe"
-)
-
-// During deepValueEqual, must keep track of checks that are
-// in progress. The comparison algorithm assumes that all
-// checks in progress are true when it reencounters them.
-// Visited comparisons are stored in a map indexed by visit.
-type visit struct {
-	a1  unsafe.Pointer
-	a2  unsafe.Pointer
-	typ Type
-}
-
-// Tests for deep equality using reflected types. The map argument tracks
-// comparisons that have already been seen, which allows short circuiting on
-// recursive types.
-func deepValueEqual(v1, v2 Value, visited map[visit]bool) bool {
-	if !v1.IsValid() || !v2.IsValid() {
-		return v1.IsValid() == v2.IsValid()
-	}
-	if v1.Type() != v2.Type() {
-		return false
-	}
-
-	// We want to avoid putting more in the visited map than we need to.
-	// For any possible reference cycle that might be encountered,
-	// hard(v1, v2) needs to return true for at least one of the types in the cycle,
-	// and it's safe and valid to get Value's internal pointer.
-	hard := func(v1, v2 Value) bool {
-		switch v1.Kind() {
-		case Pointer:
-			if v1.typ.ptrdata == 0 {
-				// go:notinheap pointers can't be cyclic.
-				// At least, all of our current uses of go:notinheap have
-				// that property. The runtime ones aren't cyclic (and we don't use
-				// DeepEqual on them anyway), and the cgo-generated ones are
-				// all empty structs.
-				return false
-			}
-			fallthrough
-		case Map, Slice, Interface:
-			// Nil pointers cannot be cyclic. Avoid putting them in the visited map.
-			return !v1.IsNil() && !v2.IsNil()
-		}
-		return false
-	}
-
-	if hard(v1, v2) {
-		// For a Pointer or Map value, we need to check flagIndir,
-		// which we do by calling the pointer method.
-		// For Slice or Interface, flagIndir is always set,
-		// and using v.ptr suffices.
-		ptrval := func(v Value) unsafe.Pointer {
-			switch v.Kind() {
-			case Pointer, Map:
-				return v.pointer()
-			default:
-				return v.ptr
-			}
-		}
-		addr1 := ptrval(v1)
-		addr2 := ptrval(v2)
-		if uintptr(addr1) > uintptr(addr2) {
-			// Canonicalize order to reduce number of entries in visited.
-			// Assumes non-moving garbage collector.
-			addr1, addr2 = addr2, addr1
-		}
-
-		// Short circuit if references are already seen.
-		typ := v1.Type()
-		v := visit{addr1, addr2, typ}
-		if visited[v] {
-			return true
-		}
-
-		// Remember for later.
-		visited[v] = true
-	}
-
-	switch v1.Kind() {
-	case Array:
-		for i := 0; i < v1.Len(); i++ {
-			if !deepValueEqual(v1.Index(i), v2.Index(i), visited) {
-				return false
-			}
-		}
-		return true
-	case Slice:
-		if v1.IsNil() != v2.IsNil() {
-			return false
-		}
-		if v1.Len() != v2.Len() {
-			return false
-		}
-		if v1.UnsafePointer() == v2.UnsafePointer() {
-			return true
-		}
-		// Special case for []byte, which is common.
-		if v1.Type().Elem().Kind() == Uint8 {
-			return bytealg.Equal(v1.Bytes(), v2.Bytes())
-		}
-		for i := 0; i < v1.Len(); i++ {
-			if !deepValueEqual(v1.Index(i), v2.Index(i), visited) {
-				return false
-			}
-		}
-		return true
-	case Interface:
-		if v1.IsNil() || v2.IsNil() {
-			return v1.IsNil() == v2.IsNil()
-		}
-		return deepValueEqual(v1.Elem(), v2.Elem(), visited)
-	case Pointer:
-		if v1.UnsafePointer() == v2.UnsafePointer() {
-			return true
-		}
-		return deepValueEqual(v1.Elem(), v2.Elem(), visited)
-	case Struct:
-		for i, n := 0, v1.NumField(); i < n; i++ {
-			if !deepValueEqual(v1.Field(i), v2.Field(i), visited) {
-				return false
-			}
-		}
-		return true
-	case Map:
-		if v1.IsNil() != v2.IsNil() {
-			return false
-		}
-		if v1.Len() != v2.Len() {
-			return false
-		}
-		if v1.UnsafePointer() == v2.UnsafePointer() {
-			return true
-		}
-		for _, k := range v1.MapKeys() {
-			val1 := v1.MapIndex(k)
-			val2 := v2.MapIndex(k)
-			if !val1.IsValid() || !val2.IsValid() || !deepValueEqual(val1, val2, visited) {
-				return false
-			}
-		}
-		return true
-	case Func:
-		if v1.IsNil() && v2.IsNil() {
-			return true
-		}
-		// Can't do better than this:
-		return false
-	case Int, Int8, Int16, Int32, Int64:
-		return v1.Int() == v2.Int()
-	case Uint, Uint8, Uint16, Uint32, Uint64, Uintptr:
-		return v1.Uint() == v2.Uint()
-	case String:
-		return v1.String() == v2.String()
-	case Bool:
-		return v1.Bool() == v2.Bool()
-	case Float32, Float64:
-		return v1.Float() == v2.Float()
-	case Complex64, Complex128:
-		return v1.Complex() == v2.Complex()
-	default:
-		// Normal equality suffices
-		return valueInterface(v1, false) == valueInterface(v2, false)
-	}
-}
-
-// DeepEqual reports whether x and y are ``deeply equal,'' defined as follows.
-// Two values of identical type are deeply equal if one of the following cases applies.
-// Values of distinct types are never deeply equal.
-//
-// Array values are deeply equal when their corresponding elements are deeply equal.
-//
-// Struct values are deeply equal if their corresponding fields,
-// both exported and unexported, are deeply equal.
-//
-// Func values are deeply equal if both are nil; otherwise they are not deeply equal.
-//
-// Interface values are deeply equal if they hold deeply equal concrete values.
-//
-// Map values are deeply equal when all of the following are true:
-// they are both nil or both non-nil, they have the same length,
-// and either they are the same map object or their corresponding keys
-// (matched using Go equality) map to deeply equal values.
-//
-// Pointer values are deeply equal if they are equal using Go's == operator
-// or if they point to deeply equal values.
-//
-// Slice values are deeply equal when all of the following are true:
-// they are both nil or both non-nil, they have the same length,
-// and either they point to the same initial entry of the same underlying array
-// (that is, &x[0] == &y[0]) or their corresponding elements (up to length) are deeply equal.
-// Note that a non-nil empty slice and a nil slice (for example, []byte{} and []byte(nil))
-// are not deeply equal.
-//
-// Other values - numbers, bools, strings, and channels - are deeply equal
-// if they are equal using Go's == operator.
-//
-// In general DeepEqual is a recursive relaxation of Go's == operator.
-// However, this idea is impossible to implement without some inconsistency.
-// Specifically, it is possible for a value to be unequal to itself,
-// either because it is of func type (uncomparable in general)
-// or because it is a floating-point NaN value (not equal to itself in floating-point comparison),
-// or because it is an array, struct, or interface containing
-// such a value.
-// On the other hand, pointer values are always equal to themselves,
-// even if they point at or contain such problematic values,
-// because they compare equal using Go's == operator, and that
-// is a sufficient condition to be deeply equal, regardless of content.
-// DeepEqual has been defined so that the same short-cut applies
-// to slices and maps: if x and y are the same slice or the same map,
-// they are deeply equal regardless of content.
-//
-// As DeepEqual traverses the data values it may find a cycle. The
-// second and subsequent times that DeepEqual compares two pointer
-// values that have been compared before, it treats the values as
-// equal rather than examining the values to which they point.
-// This ensures that DeepEqual terminates.
-func DeepEqual(x, y any) bool {
-	if x == nil || y == nil {
-		return x == y
-	}
-	v1 := ValueOf(x)
-	v2 := ValueOf(y)
-	if v1.Type() != v2.Type() {
-		return false
-	}
-	return deepValueEqual(v1, v2, make(map[visit]bool))
-}
diff --git a/contrib/go/_std_1.18/src/reflect/float32reg_generic.go b/contrib/go/_std_1.18/src/reflect/float32reg_generic.go
deleted file mode 100644
index 307c0bb33c..0000000000
--- a/contrib/go/_std_1.18/src/reflect/float32reg_generic.go
+++ /dev/null
@@ -1,23 +0,0 @@
-// Copyright 2021 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build !ppc64 && !ppc64le
-
-package reflect
-
-import "unsafe"
-
-// This file implements a straightforward conversion of a float32
-// value into its representation in a register. This conversion
-// applies for amd64 and arm64. It is also chosen for the case of
-// zero argument registers, but is not used.
-
-func archFloat32FromReg(reg uint64) float32 {
-	i := uint32(reg)
-	return *(*float32)(unsafe.Pointer(&i))
-}
-
-func archFloat32ToReg(val float32) uint64 {
-	return uint64(*(*uint32)(unsafe.Pointer(&val)))
-}
diff --git a/contrib/go/_std_1.18/src/reflect/makefunc.go b/contrib/go/_std_1.18/src/reflect/makefunc.go
deleted file mode 100644
index d0b0935cb8..0000000000
--- a/contrib/go/_std_1.18/src/reflect/makefunc.go
+++ /dev/null
@@ -1,176 +0,0 @@
-// Copyright 2012 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// MakeFunc implementation.
-
-package reflect
-
-import (
-	"internal/abi"
-	"unsafe"
-)
-
-// makeFuncImpl is the closure value implementing the function
-// returned by MakeFunc.
-// The first three words of this type must be kept in sync with
-// methodValue and runtime.reflectMethodValue.
-// Any changes should be reflected in all three.
-type makeFuncImpl struct {
-	makeFuncCtxt
-	ftyp *funcType
-	fn   func([]Value) []Value
-}
-
-// MakeFunc returns a new function of the given Type
-// that wraps the function fn. When called, that new function
-// does the following:
-//
-//	- converts its arguments to a slice of Values.
-//	- runs results := fn(args).
-//	- returns the results as a slice of Values, one per formal result.
-//
-// The implementation fn can assume that the argument Value slice
-// has the number and type of arguments given by typ.
-// If typ describes a variadic function, the final Value is itself
-// a slice representing the variadic arguments, as in the
-// body of a variadic function. The result Value slice returned by fn
-// must have the number and type of results given by typ.
-//
-// The Value.Call method allows the caller to invoke a typed function
-// in terms of Values; in contrast, MakeFunc allows the caller to implement
-// a typed function in terms of Values.
-//
-// The Examples section of the documentation includes an illustration
-// of how to use MakeFunc to build a swap function for different types.
-//
-func MakeFunc(typ Type, fn func(args []Value) (results []Value)) Value {
-	if typ.Kind() != Func {
-		panic("reflect: call of MakeFunc with non-Func type")
-	}
-
-	t := typ.common()
-	ftyp := (*funcType)(unsafe.Pointer(t))
-
-	code := abi.FuncPCABI0(makeFuncStub)
-
-	// makeFuncImpl contains a stack map for use by the runtime
-	_, _, abi := funcLayout(ftyp, nil)
-
-	impl := &makeFuncImpl{
-		makeFuncCtxt: makeFuncCtxt{
-			fn:      code,
-			stack:   abi.stackPtrs,
-			argLen:  abi.stackCallArgsSize,
-			regPtrs: abi.inRegPtrs,
-		},
-		ftyp: ftyp,
-		fn:   fn,
-	}
-
-	return Value{t, unsafe.Pointer(impl), flag(Func)}
-}
-
-// makeFuncStub is an assembly function that is the code half of
-// the function returned from MakeFunc. It expects a *callReflectFunc
-// as its context register, and its job is to invoke callReflect(ctxt, frame)
-// where ctxt is the context register and frame is a pointer to the first
-// word in the passed-in argument frame.
-func makeFuncStub()
-
-// The first 3 words of this type must be kept in sync with
-// makeFuncImpl and runtime.reflectMethodValue.
-// Any changes should be reflected in all three.
-type methodValue struct {
-	makeFuncCtxt
-	method int
-	rcvr   Value
-}
-
-// makeMethodValue converts v from the rcvr+method index representation
-// of a method value to an actual method func value, which is
-// basically the receiver value with a special bit set, into a true
-// func value - a value holding an actual func. The output is
-// semantically equivalent to the input as far as the user of package
-// reflect can tell, but the true func representation can be handled
-// by code like Convert and Interface and Assign.
-func makeMethodValue(op string, v Value) Value {
-	if v.flag&flagMethod == 0 {
-		panic("reflect: internal error: invalid use of makeMethodValue")
-	}
-
-	// Ignoring the flagMethod bit, v describes the receiver, not the method type.
-	fl := v.flag & (flagRO | flagAddr | flagIndir)
-	fl |= flag(v.typ.Kind())
-	rcvr := Value{v.typ, v.ptr, fl}
-
-	// v.Type returns the actual type of the method value.
-	ftyp := (*funcType)(unsafe.Pointer(v.Type().(*rtype)))
-
-	code := methodValueCallCodePtr()
-
-	// methodValue contains a stack map for use by the runtime
-	_, _, abi := funcLayout(ftyp, nil)
-	fv := &methodValue{
-		makeFuncCtxt: makeFuncCtxt{
-			fn:      code,
-			stack:   abi.stackPtrs,
-			argLen:  abi.stackCallArgsSize,
-			regPtrs: abi.inRegPtrs,
-		},
-		method: int(v.flag) >> flagMethodShift,
-		rcvr:   rcvr,
-	}
-
-	// Cause panic if method is not appropriate.
-	// The panic would still happen during the call if we omit this,
-	// but we want Interface() and other operations to fail early.
-	methodReceiver(op, fv.rcvr, fv.method)
-
-	return Value{&ftyp.rtype, unsafe.Pointer(fv), v.flag&flagRO | flag(Func)}
-}
-
-func methodValueCallCodePtr() uintptr {
-	return abi.FuncPCABI0(methodValueCall)
-}
-
-// methodValueCall is an assembly function that is the code half of
-// the function returned from makeMethodValue. It expects a *methodValue
-// as its context register, and its job is to invoke callMethod(ctxt, frame)
-// where ctxt is the context register and frame is a pointer to the first
-// word in the passed-in argument frame.
-func methodValueCall()
-
-// This structure must be kept in sync with runtime.reflectMethodValue.
-// Any changes should be reflected in all both.
-type makeFuncCtxt struct {
-	fn      uintptr
-	stack   *bitVector // ptrmap for both stack args and results
-	argLen  uintptr    // just args
-	regPtrs abi.IntArgRegBitmap
-}
-
-// moveMakeFuncArgPtrs uses ctxt.regPtrs to copy integer pointer arguments
-// in args.Ints to args.Ptrs where the GC can see them.
-//
-// This is similar to what reflectcallmove does in the runtime, except
-// that happens on the return path, whereas this happens on the call path.
-//
-// nosplit because pointers are being held in uintptr slots in args, so
-// having our stack scanned now could lead to accidentally freeing
-// memory.
-//go:nosplit
-func moveMakeFuncArgPtrs(ctxt *makeFuncCtxt, args *abi.RegArgs) {
-	for i, arg := range args.Ints {
-		// Avoid write barriers! Because our write barrier enqueues what
-		// was there before, we might enqueue garbage.
-		if ctxt.regPtrs.Get(i) {
-			*(*uintptr)(unsafe.Pointer(&args.Ptrs[i])) = arg
-		} else {
-			// We *must* zero this space ourselves because it's defined in
-			// assembly code and the GC will scan these pointers. Otherwise,
-			// there will be garbage here.
-			*(*uintptr)(unsafe.Pointer(&args.Ptrs[i])) = 0
-		}
-	}
-}
diff --git a/contrib/go/_std_1.18/src/reflect/type.go b/contrib/go/_std_1.18/src/reflect/type.go
deleted file mode 100644
index 8ba63bcad0..0000000000
--- a/contrib/go/_std_1.18/src/reflect/type.go
+++ /dev/null
@@ -1,3173 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package reflect implements run-time reflection, allowing a program to
-// manipulate objects with arbitrary types. The typical use is to take a value
-// with static type interface{} and extract its dynamic type information by
-// calling TypeOf, which returns a Type.
-//
-// A call to ValueOf returns a Value representing the run-time data.
-// Zero takes a Type and returns a Value representing a zero value
-// for that type.
-//
-// See "The Laws of Reflection" for an introduction to reflection in Go:
-// https://golang.org/doc/articles/laws_of_reflection.html
-package reflect
-
-import (
-	"internal/goarch"
-	"internal/unsafeheader"
-	"strconv"
-	"sync"
-	"unicode"
-	"unicode/utf8"
-	"unsafe"
-)
-
-// Type is the representation of a Go type.
-//
-// Not all methods apply to all kinds of types. Restrictions,
-// if any, are noted in the documentation for each method.
-// Use the Kind method to find out the kind of type before
-// calling kind-specific methods. Calling a method
-// inappropriate to the kind of type causes a run-time panic.
-//
-// Type values are comparable, such as with the == operator,
-// so they can be used as map keys.
-// Two Type values are equal if they represent identical types.
-type Type interface {
-	// Methods applicable to all types.
-
-	// Align returns the alignment in bytes of a value of
-	// this type when allocated in memory.
-	Align() int
-
-	// FieldAlign returns the alignment in bytes of a value of
-	// this type when used as a field in a struct.
-	FieldAlign() int
-
-	// Method returns the i'th method in the type's method set.
-	// It panics if i is not in the range [0, NumMethod()).
-	//
-	// For a non-interface type T or *T, the returned Method's Type and Func
-	// fields describe a function whose first argument is the receiver,
-	// and only exported methods are accessible.
-	//
-	// For an interface type, the returned Method's Type field gives the
-	// method signature, without a receiver, and the Func field is nil.
-	//
-	// Methods are sorted in lexicographic order.
-	Method(int) Method
-
-	// MethodByName returns the method with that name in the type's
-	// method set and a boolean indicating if the method was found.
-	//
-	// For a non-interface type T or *T, the returned Method's Type and Func
-	// fields describe a function whose first argument is the receiver.
-	//
-	// For an interface type, the returned Method's Type field gives the
-	// method signature, without a receiver, and the Func field is nil.
-	MethodByName(string) (Method, bool)
-
-	// NumMethod returns the number of methods accessible using Method.
-	//
-	// Note that NumMethod counts unexported methods only for interface types.
-	NumMethod() int
-
-	// Name returns the type's name within its package for a defined type.
-	// For other (non-defined) types it returns the empty string.
-	Name() string
-
-	// PkgPath returns a defined type's package path, that is, the import path
-	// that uniquely identifies the package, such as "encoding/base64".
-	// If the type was predeclared (string, error) or not defined (*T, struct{},
-	// []int, or A where A is an alias for a non-defined type), the package path
-	// will be the empty string.
-	PkgPath() string
-
-	// Size returns the number of bytes needed to store
-	// a value of the given type; it is analogous to unsafe.Sizeof.
-	Size() uintptr
-
-	// String returns a string representation of the type.
-	// The string representation may use shortened package names
-	// (e.g., base64 instead of "encoding/base64") and is not
-	// guaranteed to be unique among types. To test for type identity,
-	// compare the Types directly.
-	String() string
-
-	// Kind returns the specific kind of this type.
-	Kind() Kind
-
-	// Implements reports whether the type implements the interface type u.
-	Implements(u Type) bool
-
-	// AssignableTo reports whether a value of the type is assignable to type u.
-	AssignableTo(u Type) bool
-
-	// ConvertibleTo reports whether a value of the type is convertible to type u.
-	// Even if ConvertibleTo returns true, the conversion may still panic.
-	// For example, a slice of type []T is convertible to *[N]T,
-	// but the conversion will panic if its length is less than N.
-	ConvertibleTo(u Type) bool
-
-	// Comparable reports whether values of this type are comparable.
-	// Even if Comparable returns true, the comparison may still panic.
-	// For example, values of interface type are comparable,
-	// but the comparison will panic if their dynamic type is not comparable.
-	Comparable() bool
-
-	// Methods applicable only to some types, depending on Kind.
-	// The methods allowed for each kind are:
-	//
-	//	Int*, Uint*, Float*, Complex*: Bits
-	//	Array: Elem, Len
-	//	Chan: ChanDir, Elem
-	//	Func: In, NumIn, Out, NumOut, IsVariadic.
-	//	Map: Key, Elem
-	//	Pointer: Elem
-	//	Slice: Elem
-	//	Struct: Field, FieldByIndex, FieldByName, FieldByNameFunc, NumField
-
-	// Bits returns the size of the type in bits.
-	// It panics if the type's Kind is not one of the
-	// sized or unsized Int, Uint, Float, or Complex kinds.
-	Bits() int
-
-	// ChanDir returns a channel type's direction.
-	// It panics if the type's Kind is not Chan.
-	ChanDir() ChanDir
-
-	// IsVariadic reports whether a function type's final input parameter
-	// is a "..." parameter. If so, t.In(t.NumIn() - 1) returns the parameter's
-	// implicit actual type []T.
-	//
-	// For concreteness, if t represents func(x int, y ... float64), then
-	//
-	//	t.NumIn() == 2
-	//	t.In(0) is the reflect.Type for "int"
-	//	t.In(1) is the reflect.Type for "[]float64"
-	//	t.IsVariadic() == true
-	//
-	// IsVariadic panics if the type's Kind is not Func.
-	IsVariadic() bool
-
-	// Elem returns a type's element type.
-	// It panics if the type's Kind is not Array, Chan, Map, Pointer, or Slice.
-	Elem() Type
-
-	// Field returns a struct type's i'th field.
-	// It panics if the type's Kind is not Struct.
-	// It panics if i is not in the range [0, NumField()).
-	Field(i int) StructField
-
-	// FieldByIndex returns the nested field corresponding
-	// to the index sequence. It is equivalent to calling Field
-	// successively for each index i.
-	// It panics if the type's Kind is not Struct.
-	FieldByIndex(index []int) StructField
-
-	// FieldByName returns the struct field with the given name
-	// and a boolean indicating if the field was found.
-	FieldByName(name string) (StructField, bool)
-
-	// FieldByNameFunc returns the struct field with a name
-	// that satisfies the match function and a boolean indicating if
-	// the field was found.
-	//
-	// FieldByNameFunc considers the fields in the struct itself
-	// and then the fields in any embedded structs, in breadth first order,
-	// stopping at the shallowest nesting depth containing one or more
-	// fields satisfying the match function. If multiple fields at that depth
-	// satisfy the match function, they cancel each other
-	// and FieldByNameFunc returns no match.
-	// This behavior mirrors Go's handling of name lookup in
-	// structs containing embedded fields.
-	FieldByNameFunc(match func(string) bool) (StructField, bool)
-
-	// In returns the type of a function type's i'th input parameter.
-	// It panics if the type's Kind is not Func.
-	// It panics if i is not in the range [0, NumIn()).
-	In(i int) Type
-
-	// Key returns a map type's key type.
-	// It panics if the type's Kind is not Map.
-	Key() Type
-
-	// Len returns an array type's length.
-	// It panics if the type's Kind is not Array.
-	Len() int
-
-	// NumField returns a struct type's field count.
-	// It panics if the type's Kind is not Struct.
-	NumField() int
-
-	// NumIn returns a function type's input parameter count.
-	// It panics if the type's Kind is not Func.
-	NumIn() int
-
-	// NumOut returns a function type's output parameter count.
-	// It panics if the type's Kind is not Func.
-	NumOut() int
-
-	// Out returns the type of a function type's i'th output parameter.
-	// It panics if the type's Kind is not Func.
-	// It panics if i is not in the range [0, NumOut()).
-	Out(i int) Type
-
-	common() *rtype
-	uncommon() *uncommonType
-}
-
-// BUG(rsc): FieldByName and related functions consider struct field names to be equal
-// if the names are equal, even if they are unexported names originating
-// in different packages. The practical effect of this is that the result of
-// t.FieldByName("x") is not well defined if the struct type t contains
-// multiple fields named x (embedded from different packages).
-// FieldByName may return one of the fields named x or may report that there are none.
-// See https://golang.org/issue/4876 for more details.
-
-/*
- * These data structures are known to the compiler (../cmd/compile/internal/reflectdata/reflect.go).
- * A few are known to ../runtime/type.go to convey to debuggers.
- * They are also known to ../runtime/type.go.
- */
-
-// A Kind represents the specific kind of type that a Type represents.
-// The zero Kind is not a valid kind.
-type Kind uint
-
-const (
-	Invalid Kind = iota
-	Bool
-	Int
-	Int8
-	Int16
-	Int32
-	Int64
-	Uint
-	Uint8
-	Uint16
-	Uint32
-	Uint64
-	Uintptr
-	Float32
-	Float64
-	Complex64
-	Complex128
-	Array
-	Chan
-	Func
-	Interface
-	Map
-	Pointer
-	Slice
-	String
-	Struct
-	UnsafePointer
-)
-
-// Ptr is the old name for the Pointer kind.
-const Ptr = Pointer
-
-// tflag is used by an rtype to signal what extra type information is
-// available in the memory directly following the rtype value.
-//
-// tflag values must be kept in sync with copies in:
-//	cmd/compile/internal/reflectdata/reflect.go
-//	cmd/link/internal/ld/decodesym.go
-//	runtime/type.go
-type tflag uint8
-
-const (
-	// tflagUncommon means that there is a pointer, *uncommonType,
-	// just beyond the outer type structure.
-	//
-	// For example, if t.Kind() == Struct and t.tflag&tflagUncommon != 0,
-	// then t has uncommonType data and it can be accessed as:
-	//
-	//	type tUncommon struct {
-	//		structType
-	//		u uncommonType
-	//	}
-	//	u := &(*tUncommon)(unsafe.Pointer(t)).u
-	tflagUncommon tflag = 1 << 0
-
-	// tflagExtraStar means the name in the str field has an
-	// extraneous '*' prefix. This is because for most types T in
-	// a program, the type *T also exists and reusing the str data
-	// saves binary size.
-	tflagExtraStar tflag = 1 << 1
-
-	// tflagNamed means the type has a name.
-	tflagNamed tflag = 1 << 2
-
-	// tflagRegularMemory means that equal and hash functions can treat
-	// this type as a single region of t.size bytes.
-	tflagRegularMemory tflag = 1 << 3
-)
-
-// rtype is the common implementation of most values.
-// It is embedded in other struct types.
-//
-// rtype must be kept in sync with ../runtime/type.go:/^type._type.
-type rtype struct {
-	size       uintptr
-	ptrdata    uintptr // number of bytes in the type that can contain pointers
-	hash       uint32  // hash of type; avoids computation in hash tables
-	tflag      tflag   // extra type information flags
-	align      uint8   // alignment of variable with this type
-	fieldAlign uint8   // alignment of struct field with this type
-	kind       uint8   // enumeration for C
-	// function for comparing objects of this type
-	// (ptr to object A, ptr to object B) -> ==?
-	equal     func(unsafe.Pointer, unsafe.Pointer) bool
-	gcdata    *byte   // garbage collection data
-	str       nameOff // string form
-	ptrToThis typeOff // type for pointer to this type, may be zero
-}
-
-// Method on non-interface type
-type method struct {
-	name nameOff // name of method
-	mtyp typeOff // method type (without receiver)
-	ifn  textOff // fn used in interface call (one-word receiver)
-	tfn  textOff // fn used for normal method call
-}
-
-// uncommonType is present only for defined types or types with methods
-// (if T is a defined type, the uncommonTypes for T and *T have methods).
-// Using a pointer to this struct reduces the overall size required
-// to describe a non-defined type with no methods.
-type uncommonType struct {
-	pkgPath nameOff // import path; empty for built-in types like int, string
-	mcount  uint16  // number of methods
-	xcount  uint16  // number of exported methods
-	moff    uint32  // offset from this uncommontype to [mcount]method
-	_       uint32  // unused
-}
-
-// ChanDir represents a channel type's direction.
-type ChanDir int
-
-const (
-	RecvDir ChanDir             = 1 << iota // <-chan
-	SendDir                                 // chan<-
-	BothDir = RecvDir | SendDir             // chan
-)
-
-// arrayType represents a fixed array type.
-type arrayType struct {
-	rtype
-	elem  *rtype // array element type
-	slice *rtype // slice type
-	len   uintptr
-}
-
-// chanType represents a channel type.
-type chanType struct {
-	rtype
-	elem *rtype  // channel element type
-	dir  uintptr // channel direction (ChanDir)
-}
-
-// funcType represents a function type.
-//
-// A *rtype for each in and out parameter is stored in an array that
-// directly follows the funcType (and possibly its uncommonType). So
-// a function type with one method, one input, and one output is:
-//
-//	struct {
-//		funcType
-//		uncommonType
-//		[2]*rtype    // [0] is in, [1] is out
-//	}
-type funcType struct {
-	rtype
-	inCount  uint16
-	outCount uint16 // top bit is set if last input parameter is ...
-}
-
-// imethod represents a method on an interface type
-type imethod struct {
-	name nameOff // name of method
-	typ  typeOff // .(*FuncType) underneath
-}
-
-// interfaceType represents an interface type.
-type interfaceType struct {
-	rtype
-	pkgPath name      // import path
-	methods []imethod // sorted by hash
-}
-
-// mapType represents a map type.
-type mapType struct {
-	rtype
-	key    *rtype // map key type
-	elem   *rtype // map element (value) type
-	bucket *rtype // internal bucket structure
-	// function for hashing keys (ptr to key, seed) -> hash
-	hasher     func(unsafe.Pointer, uintptr) uintptr
-	keysize    uint8  // size of key slot
-	valuesize  uint8  // size of value slot
-	bucketsize uint16 // size of bucket
-	flags      uint32
-}
-
-// ptrType represents a pointer type.
-type ptrType struct {
-	rtype
-	elem *rtype // pointer element (pointed at) type
-}
-
-// sliceType represents a slice type.
-type sliceType struct {
-	rtype
-	elem *rtype // slice element type
-}
-
-// Struct field
-type structField struct {
-	name        name    // name is always non-empty
-	typ         *rtype  // type of field
-	offsetEmbed uintptr // byte offset of field<<1 | isEmbedded
-}
-
-func (f *structField) offset() uintptr {
-	return f.offsetEmbed >> 1
-}
-
-func (f *structField) embedded() bool {
-	return f.offsetEmbed&1 != 0
-}
-
-// structType represents a struct type.
-type structType struct {
-	rtype
-	pkgPath name
-	fields  []structField // sorted by offset
-}
-
-// name is an encoded type name with optional extra data.
-//
-// The first byte is a bit field containing:
-//
-//	1<<0 the name is exported
-//	1<<1 tag data follows the name
-//	1<<2 pkgPath nameOff follows the name and tag
-//
-// Following that, there is a varint-encoded length of the name,
-// followed by the name itself.
-//
-// If tag data is present, it also has a varint-encoded length
-// followed by the tag itself.
-//
-// If the import path follows, then 4 bytes at the end of
-// the data form a nameOff. The import path is only set for concrete
-// methods that are defined in a different package than their type.
-//
-// If a name starts with "*", then the exported bit represents
-// whether the pointed to type is exported.
-//
-// Note: this encoding must match here and in:
-//   cmd/compile/internal/reflectdata/reflect.go
-//   runtime/type.go
-//   internal/reflectlite/type.go
-//   cmd/link/internal/ld/decodesym.go
-
-type name struct {
-	bytes *byte
-}
-
-func (n name) data(off int, whySafe string) *byte {
-	return (*byte)(add(unsafe.Pointer(n.bytes), uintptr(off), whySafe))
-}
-
-func (n name) isExported() bool {
-	return (*n.bytes)&(1<<0) != 0
-}
-
-func (n name) hasTag() bool {
-	return (*n.bytes)&(1<<1) != 0
-}
-
-// readVarint parses a varint as encoded by encoding/binary.
-// It returns the number of encoded bytes and the encoded value.
-func (n name) readVarint(off int) (int, int) {
-	v := 0
-	for i := 0; ; i++ {
-		x := *n.data(off+i, "read varint")
-		v += int(x&0x7f) << (7 * i)
-		if x&0x80 == 0 {
-			return i + 1, v
-		}
-	}
-}
-
-// writeVarint writes n to buf in varint form. Returns the
-// number of bytes written. n must be nonnegative.
-// Writes at most 10 bytes.
-func writeVarint(buf []byte, n int) int {
-	for i := 0; ; i++ {
-		b := byte(n & 0x7f)
-		n >>= 7
-		if n == 0 {
-			buf[i] = b
-			return i + 1
-		}
-		buf[i] = b | 0x80
-	}
-}
-
-func (n name) name() (s string) {
-	if n.bytes == nil {
-		return
-	}
-	i, l := n.readVarint(1)
-	hdr := (*unsafeheader.String)(unsafe.Pointer(&s))
-	hdr.Data = unsafe.Pointer(n.data(1+i, "non-empty string"))
-	hdr.Len = l
-	return
-}
-
-func (n name) tag() (s string) {
-	if !n.hasTag() {
-		return ""
-	}
-	i, l := n.readVarint(1)
-	i2, l2 := n.readVarint(1 + i + l)
-	hdr := (*unsafeheader.String)(unsafe.Pointer(&s))
-	hdr.Data = unsafe.Pointer(n.data(1+i+l+i2, "non-empty string"))
-	hdr.Len = l2
-	return
-}
-
-func (n name) pkgPath() string {
-	if n.bytes == nil || *n.data(0, "name flag field")&(1<<2) == 0 {
-		return ""
-	}
-	i, l := n.readVarint(1)
-	off := 1 + i + l
-	if n.hasTag() {
-		i2, l2 := n.readVarint(off)
-		off += i2 + l2
-	}
-	var nameOff int32
-	// Note that this field may not be aligned in memory,
-	// so we cannot use a direct int32 assignment here.
-	copy((*[4]byte)(unsafe.Pointer(&nameOff))[:], (*[4]byte)(unsafe.Pointer(n.data(off, "name offset field")))[:])
-	pkgPathName := name{(*byte)(resolveTypeOff(unsafe.Pointer(n.bytes), nameOff))}
-	return pkgPathName.name()
-}
-
-func newName(n, tag string, exported bool) name {
-	if len(n) >= 1<<29 {
-		panic("reflect.nameFrom: name too long: " + n[:1024] + "...")
-	}
-	if len(tag) >= 1<<29 {
-		panic("reflect.nameFrom: tag too long: " + tag[:1024] + "...")
-	}
-	var nameLen [10]byte
-	var tagLen [10]byte
-	nameLenLen := writeVarint(nameLen[:], len(n))
-	tagLenLen := writeVarint(tagLen[:], len(tag))
-
-	var bits byte
-	l := 1 + nameLenLen + len(n)
-	if exported {
-		bits |= 1 << 0
-	}
-	if len(tag) > 0 {
-		l += tagLenLen + len(tag)
-		bits |= 1 << 1
-	}
-
-	b := make([]byte, l)
-	b[0] = bits
-	copy(b[1:], nameLen[:nameLenLen])
-	copy(b[1+nameLenLen:], n)
-	if len(tag) > 0 {
-		tb := b[1+nameLenLen+len(n):]
-		copy(tb, tagLen[:tagLenLen])
-		copy(tb[tagLenLen:], tag)
-	}
-
-	return name{bytes: &b[0]}
-}
-
-/*
- * The compiler knows the exact layout of all the data structures above.
- * The compiler does not know about the data structures and methods below.
- */
-
-// Method represents a single method.
-type Method struct {
-	// Name is the method name.
-	Name string
-
-	// PkgPath is the package path that qualifies a lower case (unexported)
-	// method name. It is empty for upper case (exported) method names.
-	// The combination of PkgPath and Name uniquely identifies a method
-	// in a method set.
-	// See https://golang.org/ref/spec#Uniqueness_of_identifiers
-	PkgPath string
-
-	Type  Type  // method type
-	Func  Value // func with receiver as first argument
-	Index int   // index for Type.Method
-}
-
-// IsExported reports whether the method is exported.
-func (m Method) IsExported() bool {
-	return m.PkgPath == ""
-}
-
-const (
-	kindDirectIface = 1 << 5
-	kindGCProg      = 1 << 6 // Type.gc points to GC program
-	kindMask        = (1 << 5) - 1
-)
-
-// String returns the name of k.
-func (k Kind) String() string {
-	if int(k) < len(kindNames) {
-		return kindNames[k]
-	}
-	return "kind" + strconv.Itoa(int(k))
-}
-
-var kindNames = []string{
-	Invalid:       "invalid",
-	Bool:          "bool",
-	Int:           "int",
-	Int8:          "int8",
-	Int16:         "int16",
-	Int32:         "int32",
-	Int64:         "int64",
-	Uint:          "uint",
-	Uint8:         "uint8",
-	Uint16:        "uint16",
-	Uint32:        "uint32",
-	Uint64:        "uint64",
-	Uintptr:       "uintptr",
-	Float32:       "float32",
-	Float64:       "float64",
-	Complex64:     "complex64",
-	Complex128:    "complex128",
-	Array:         "array",
-	Chan:          "chan",
-	Func:          "func",
-	Interface:     "interface",
-	Map:           "map",
-	Pointer:       "ptr",
-	Slice:         "slice",
-	String:        "string",
-	Struct:        "struct",
-	UnsafePointer: "unsafe.Pointer",
-}
-
-func (t *uncommonType) methods() []method {
-	if t.mcount == 0 {
-		return nil
-	}
-	return (*[1 << 16]method)(add(unsafe.Pointer(t), uintptr(t.moff), "t.mcount > 0"))[:t.mcount:t.mcount]
-}
-
-func (t *uncommonType) exportedMethods() []method {
-	if t.xcount == 0 {
-		return nil
-	}
-	return (*[1 << 16]method)(add(unsafe.Pointer(t), uintptr(t.moff), "t.xcount > 0"))[:t.xcount:t.xcount]
-}
-
-// resolveNameOff resolves a name offset from a base pointer.
-// The (*rtype).nameOff method is a convenience wrapper for this function.
-// Implemented in the runtime package.
-func resolveNameOff(ptrInModule unsafe.Pointer, off int32) unsafe.Pointer
-
-// resolveTypeOff resolves an *rtype offset from a base type.
-// The (*rtype).typeOff method is a convenience wrapper for this function.
-// Implemented in the runtime package.
-func resolveTypeOff(rtype unsafe.Pointer, off int32) unsafe.Pointer
-
-// resolveTextOff resolves a function pointer offset from a base type.
-// The (*rtype).textOff method is a convenience wrapper for this function.
-// Implemented in the runtime package.
-func resolveTextOff(rtype unsafe.Pointer, off int32) unsafe.Pointer
-
-// addReflectOff adds a pointer to the reflection lookup map in the runtime.
-// It returns a new ID that can be used as a typeOff or textOff, and will
-// be resolved correctly. Implemented in the runtime package.
-func addReflectOff(ptr unsafe.Pointer) int32
-
-// resolveReflectName adds a name to the reflection lookup map in the runtime.
-// It returns a new nameOff that can be used to refer to the pointer.
-func resolveReflectName(n name) nameOff {
-	return nameOff(addReflectOff(unsafe.Pointer(n.bytes)))
-}
-
-// resolveReflectType adds a *rtype to the reflection lookup map in the runtime.
-// It returns a new typeOff that can be used to refer to the pointer.
-func resolveReflectType(t *rtype) typeOff {
-	return typeOff(addReflectOff(unsafe.Pointer(t)))
-}
-
-// resolveReflectText adds a function pointer to the reflection lookup map in
-// the runtime. It returns a new textOff that can be used to refer to the
-// pointer.
-func resolveReflectText(ptr unsafe.Pointer) textOff {
-	return textOff(addReflectOff(ptr))
-}
-
-type nameOff int32 // offset to a name
-type typeOff int32 // offset to an *rtype
-type textOff int32 // offset from top of text section
-
-func (t *rtype) nameOff(off nameOff) name {
-	return name{(*byte)(resolveNameOff(unsafe.Pointer(t), int32(off)))}
-}
-
-func (t *rtype) typeOff(off typeOff) *rtype {
-	return (*rtype)(resolveTypeOff(unsafe.Pointer(t), int32(off)))
-}
-
-func (t *rtype) textOff(off textOff) unsafe.Pointer {
-	return resolveTextOff(unsafe.Pointer(t), int32(off))
-}
-
-func (t *rtype) uncommon() *uncommonType {
-	if t.tflag&tflagUncommon == 0 {
-		return nil
-	}
-	switch t.Kind() {
-	case Struct:
-		return &(*structTypeUncommon)(unsafe.Pointer(t)).u
-	case Pointer:
-		type u struct {
-			ptrType
-			u uncommonType
-		}
-		return &(*u)(unsafe.Pointer(t)).u
-	case Func:
-		type u struct {
-			funcType
-			u uncommonType
-		}
-		return &(*u)(unsafe.Pointer(t)).u
-	case Slice:
-		type u struct {
-			sliceType
-			u uncommonType
-		}
-		return &(*u)(unsafe.Pointer(t)).u
-	case Array:
-		type u struct {
-			arrayType
-			u uncommonType
-		}
-		return &(*u)(unsafe.Pointer(t)).u
-	case Chan:
-		type u struct {
-			chanType
-			u uncommonType
-		}
-		return &(*u)(unsafe.Pointer(t)).u
-	case Map:
-		type u struct {
-			mapType
-			u uncommonType
-		}
-		return &(*u)(unsafe.Pointer(t)).u
-	case Interface:
-		type u struct {
-			interfaceType
-			u uncommonType
-		}
-		return &(*u)(unsafe.Pointer(t)).u
-	default:
-		type u struct {
-			rtype
-			u uncommonType
-		}
-		return &(*u)(unsafe.Pointer(t)).u
-	}
-}
-
-func (t *rtype) String() string {
-	s := t.nameOff(t.str).name()
-	if t.tflag&tflagExtraStar != 0 {
-		return s[1:]
-	}
-	return s
-}
-
-func (t *rtype) Size() uintptr { return t.size }
-
-func (t *rtype) Bits() int {
-	if t == nil {
-		panic("reflect: Bits of nil Type")
-	}
-	k := t.Kind()
-	if k < Int || k > Complex128 {
-		panic("reflect: Bits of non-arithmetic Type " + t.String())
-	}
-	return int(t.size) * 8
-}
-
-func (t *rtype) Align() int { return int(t.align) }
-
-func (t *rtype) FieldAlign() int { return int(t.fieldAlign) }
-
-func (t *rtype) Kind() Kind { return Kind(t.kind & kindMask) }
-
-func (t *rtype) pointers() bool { return t.ptrdata != 0 }
-
-func (t *rtype) common() *rtype { return t }
-
-func (t *rtype) exportedMethods() []method {
-	ut := t.uncommon()
-	if ut == nil {
-		return nil
-	}
-	return ut.exportedMethods()
-}
-
-func (t *rtype) NumMethod() int {
-	if t.Kind() == Interface {
-		tt := (*interfaceType)(unsafe.Pointer(t))
-		return tt.NumMethod()
-	}
-	return len(t.exportedMethods())
-}
-
-func (t *rtype) Method(i int) (m Method) {
-	if t.Kind() == Interface {
-		tt := (*interfaceType)(unsafe.Pointer(t))
-		return tt.Method(i)
-	}
-	methods := t.exportedMethods()
-	if i < 0 || i >= len(methods) {
-		panic("reflect: Method index out of range")
-	}
-	p := methods[i]
-	pname := t.nameOff(p.name)
-	m.Name = pname.name()
-	fl := flag(Func)
-	mtyp := t.typeOff(p.mtyp)
-	ft := (*funcType)(unsafe.Pointer(mtyp))
-	in := make([]Type, 0, 1+len(ft.in()))
-	in = append(in, t)
-	for _, arg := range ft.in() {
-		in = append(in, arg)
-	}
-	out := make([]Type, 0, len(ft.out()))
-	for _, ret := range ft.out() {
-		out = append(out, ret)
-	}
-	mt := FuncOf(in, out, ft.IsVariadic())
-	m.Type = mt
-	tfn := t.textOff(p.tfn)
-	fn := unsafe.Pointer(&tfn)
-	m.Func = Value{mt.(*rtype), fn, fl}
-
-	m.Index = i
-	return m
-}
-
-func (t *rtype) MethodByName(name string) (m Method, ok bool) {
-	if t.Kind() == Interface {
-		tt := (*interfaceType)(unsafe.Pointer(t))
-		return tt.MethodByName(name)
-	}
-	ut := t.uncommon()
-	if ut == nil {
-		return Method{}, false
-	}
-	// TODO(mdempsky): Binary search.
-	for i, p := range ut.exportedMethods() {
-		if t.nameOff(p.name).name() == name {
-			return t.Method(i), true
-		}
-	}
-	return Method{}, false
-}
-
-func (t *rtype) PkgPath() string {
-	if t.tflag&tflagNamed == 0 {
-		return ""
-	}
-	ut := t.uncommon()
-	if ut == nil {
-		return ""
-	}
-	return t.nameOff(ut.pkgPath).name()
-}
-
-func (t *rtype) hasName() bool {
-	return t.tflag&tflagNamed != 0
-}
-
-func (t *rtype) Name() string {
-	if !t.hasName() {
-		return ""
-	}
-	s := t.String()
-	i := len(s) - 1
-	sqBrackets := 0
-	for i >= 0 && (s[i] != '.' || sqBrackets != 0) {
-		switch s[i] {
-		case ']':
-			sqBrackets++
-		case '[':
-			sqBrackets--
-		}
-		i--
-	}
-	return s[i+1:]
-}
-
-func (t *rtype) ChanDir() ChanDir {
-	if t.Kind() != Chan {
-		panic("reflect: ChanDir of non-chan type " + t.String())
-	}
-	tt := (*chanType)(unsafe.Pointer(t))
-	return ChanDir(tt.dir)
-}
-
-func (t *rtype) IsVariadic() bool {
-	if t.Kind() != Func {
-		panic("reflect: IsVariadic of non-func type " + t.String())
-	}
-	tt := (*funcType)(unsafe.Pointer(t))
-	return tt.outCount&(1<<15) != 0
-}
-
-func (t *rtype) Elem() Type {
-	switch t.Kind() {
-	case Array:
-		tt := (*arrayType)(unsafe.Pointer(t))
-		return toType(tt.elem)
-	case Chan:
-		tt := (*chanType)(unsafe.Pointer(t))
-		return toType(tt.elem)
-	case Map:
-		tt := (*mapType)(unsafe.Pointer(t))
-		return toType(tt.elem)
-	case Pointer:
-		tt := (*ptrType)(unsafe.Pointer(t))
-		return toType(tt.elem)
-	case Slice:
-		tt := (*sliceType)(unsafe.Pointer(t))
-		return toType(tt.elem)
-	}
-	panic("reflect: Elem of invalid type " + t.String())
-}
-
-func (t *rtype) Field(i int) StructField {
-	if t.Kind() != Struct {
-		panic("reflect: Field of non-struct type " + t.String())
-	}
-	tt := (*structType)(unsafe.Pointer(t))
-	return tt.Field(i)
-}
-
-func (t *rtype) FieldByIndex(index []int) StructField {
-	if t.Kind() != Struct {
-		panic("reflect: FieldByIndex of non-struct type " + t.String())
-	}
-	tt := (*structType)(unsafe.Pointer(t))
-	return tt.FieldByIndex(index)
-}
-
-func (t *rtype) FieldByName(name string) (StructField, bool) {
-	if t.Kind() != Struct {
-		panic("reflect: FieldByName of non-struct type " + t.String())
-	}
-	tt := (*structType)(unsafe.Pointer(t))
-	return tt.FieldByName(name)
-}
-
-func (t *rtype) FieldByNameFunc(match func(string) bool) (StructField, bool) {
-	if t.Kind() != Struct {
-		panic("reflect: FieldByNameFunc of non-struct type " + t.String())
-	}
-	tt := (*structType)(unsafe.Pointer(t))
-	return tt.FieldByNameFunc(match)
-}
-
-func (t *rtype) In(i int) Type {
-	if t.Kind() != Func {
-		panic("reflect: In of non-func type " + t.String())
-	}
-	tt := (*funcType)(unsafe.Pointer(t))
-	return toType(tt.in()[i])
-}
-
-func (t *rtype) Key() Type {
-	if t.Kind() != Map {
-		panic("reflect: Key of non-map type " + t.String())
-	}
-	tt := (*mapType)(unsafe.Pointer(t))
-	return toType(tt.key)
-}
-
-func (t *rtype) Len() int {
-	if t.Kind() != Array {
-		panic("reflect: Len of non-array type " + t.String())
-	}
-	tt := (*arrayType)(unsafe.Pointer(t))
-	return int(tt.len)
-}
-
-func (t *rtype) NumField() int {
-	if t.Kind() != Struct {
-		panic("reflect: NumField of non-struct type " + t.String())
-	}
-	tt := (*structType)(unsafe.Pointer(t))
-	return len(tt.fields)
-}
-
-func (t *rtype) NumIn() int {
-	if t.Kind() != Func {
-		panic("reflect: NumIn of non-func type " + t.String())
-	}
-	tt := (*funcType)(unsafe.Pointer(t))
-	return int(tt.inCount)
-}
-
-func (t *rtype) NumOut() int {
-	if t.Kind() != Func {
-		panic("reflect: NumOut of non-func type " + t.String())
-	}
-	tt := (*funcType)(unsafe.Pointer(t))
-	return len(tt.out())
-}
-
-func (t *rtype) Out(i int) Type {
-	if t.Kind() != Func {
-		panic("reflect: Out of non-func type " + t.String())
-	}
-	tt := (*funcType)(unsafe.Pointer(t))
-	return toType(tt.out()[i])
-}
-
-func (t *funcType) in() []*rtype {
-	uadd := unsafe.Sizeof(*t)
-	if t.tflag&tflagUncommon != 0 {
-		uadd += unsafe.Sizeof(uncommonType{})
-	}
-	if t.inCount == 0 {
-		return nil
-	}
-	return (*[1 << 20]*rtype)(add(unsafe.Pointer(t), uadd, "t.inCount > 0"))[:t.inCount:t.inCount]
-}
-
-func (t *funcType) out() []*rtype {
-	uadd := unsafe.Sizeof(*t)
-	if t.tflag&tflagUncommon != 0 {
-		uadd += unsafe.Sizeof(uncommonType{})
-	}
-	outCount := t.outCount & (1<<15 - 1)
-	if outCount == 0 {
-		return nil
-	}
-	return (*[1 << 20]*rtype)(add(unsafe.Pointer(t), uadd, "outCount > 0"))[t.inCount : t.inCount+outCount : t.inCount+outCount]
-}
-
-// add returns p+x.
-//
-// The whySafe string is ignored, so that the function still inlines
-// as efficiently as p+x, but all call sites should use the string to
-// record why the addition is safe, which is to say why the addition
-// does not cause x to advance to the very end of p's allocation
-// and therefore point incorrectly at the next block in memory.
-func add(p unsafe.Pointer, x uintptr, whySafe string) unsafe.Pointer {
-	return unsafe.Pointer(uintptr(p) + x)
-}
-
-func (d ChanDir) String() string {
-	switch d {
-	case SendDir:
-		return "chan<-"
-	case RecvDir:
-		return "<-chan"
-	case BothDir:
-		return "chan"
-	}
-	return "ChanDir" + strconv.Itoa(int(d))
-}
-
-// Method returns the i'th method in the type's method set.
-func (t *interfaceType) Method(i int) (m Method) {
-	if i < 0 || i >= len(t.methods) {
-		return
-	}
-	p := &t.methods[i]
-	pname := t.nameOff(p.name)
-	m.Name = pname.name()
-	if !pname.isExported() {
-		m.PkgPath = pname.pkgPath()
-		if m.PkgPath == "" {
-			m.PkgPath = t.pkgPath.name()
-		}
-	}
-	m.Type = toType(t.typeOff(p.typ))
-	m.Index = i
-	return
-}
-
-// NumMethod returns the number of interface methods in the type's method set.
-func (t *interfaceType) NumMethod() int { return len(t.methods) }
-
-// MethodByName method with the given name in the type's method set.
-func (t *interfaceType) MethodByName(name string) (m Method, ok bool) {
-	if t == nil {
-		return
-	}
-	var p *imethod
-	for i := range t.methods {
-		p = &t.methods[i]
-		if t.nameOff(p.name).name() == name {
-			return t.Method(i), true
-		}
-	}
-	return
-}
-
-// A StructField describes a single field in a struct.
-type StructField struct {
-	// Name is the field name.
-	Name string
-
-	// PkgPath is the package path that qualifies a lower case (unexported)
-	// field name. It is empty for upper case (exported) field names.
-	// See https://golang.org/ref/spec#Uniqueness_of_identifiers
-	PkgPath string
-
-	Type      Type      // field type
-	Tag       StructTag // field tag string
-	Offset    uintptr   // offset within struct, in bytes
-	Index     []int     // index sequence for Type.FieldByIndex
-	Anonymous bool      // is an embedded field
-}
-
-// IsExported reports whether the field is exported.
-func (f StructField) IsExported() bool {
-	return f.PkgPath == ""
-}
-
-// A StructTag is the tag string in a struct field.
-//
-// By convention, tag strings are a concatenation of
-// optionally space-separated key:"value" pairs.
-// Each key is a non-empty string consisting of non-control
-// characters other than space (U+0020 ' '), quote (U+0022 '"'),
-// and colon (U+003A ':').  Each value is quoted using U+0022 '"'
-// characters and Go string literal syntax.
-type StructTag string
-
-// Get returns the value associated with key in the tag string.
-// If there is no such key in the tag, Get returns the empty string.
-// If the tag does not have the conventional format, the value
-// returned by Get is unspecified. To determine whether a tag is
-// explicitly set to the empty string, use Lookup.
-func (tag StructTag) Get(key string) string {
-	v, _ := tag.Lookup(key)
-	return v
-}
-
-// Lookup returns the value associated with key in the tag string.
-// If the key is present in the tag the value (which may be empty)
-// is returned. Otherwise the returned value will be the empty string.
-// The ok return value reports whether the value was explicitly set in
-// the tag string. If the tag does not have the conventional format,
-// the value returned by Lookup is unspecified.
-func (tag StructTag) Lookup(key string) (value string, ok bool) {
-	// When modifying this code, also update the validateStructTag code
-	// in cmd/vet/structtag.go.
-
-	for tag != "" {
-		// Skip leading space.
-		i := 0
-		for i < len(tag) && tag[i] == ' ' {
-			i++
-		}
-		tag = tag[i:]
-		if tag == "" {
-			break
-		}
-
-		// Scan to colon. A space, a quote or a control character is a syntax error.
-		// Strictly speaking, control chars include the range [0x7f, 0x9f], not just
-		// [0x00, 0x1f], but in practice, we ignore the multi-byte control characters
-		// as it is simpler to inspect the tag's bytes than the tag's runes.
-		i = 0
-		for i < len(tag) && tag[i] > ' ' && tag[i] != ':' && tag[i] != '"' && tag[i] != 0x7f {
-			i++
-		}
-		if i == 0 || i+1 >= len(tag) || tag[i] != ':' || tag[i+1] != '"' {
-			break
-		}
-		name := string(tag[:i])
-		tag = tag[i+1:]
-
-		// Scan quoted string to find value.
-		i = 1
-		for i < len(tag) && tag[i] != '"' {
-			if tag[i] == '\\' {
-				i++
-			}
-			i++
-		}
-		if i >= len(tag) {
-			break
-		}
-		qvalue := string(tag[:i+1])
-		tag = tag[i+1:]
-
-		if key == name {
-			value, err := strconv.Unquote(qvalue)
-			if err != nil {
-				break
-			}
-			return value, true
-		}
-	}
-	return "", false
-}
-
-// Field returns the i'th struct field.
-func (t *structType) Field(i int) (f StructField) {
-	if i < 0 || i >= len(t.fields) {
-		panic("reflect: Field index out of bounds")
-	}
-	p := &t.fields[i]
-	f.Type = toType(p.typ)
-	f.Name = p.name.name()
-	f.Anonymous = p.embedded()
-	if !p.name.isExported() {
-		f.PkgPath = t.pkgPath.name()
-	}
-	if tag := p.name.tag(); tag != "" {
-		f.Tag = StructTag(tag)
-	}
-	f.Offset = p.offset()
-
-	// NOTE(rsc): This is the only allocation in the interface
-	// presented by a reflect.Type. It would be nice to avoid,
-	// at least in the common cases, but we need to make sure
-	// that misbehaving clients of reflect cannot affect other
-	// uses of reflect. One possibility is CL 5371098, but we
-	// postponed that ugliness until there is a demonstrated
-	// need for the performance. This is issue 2320.
-	f.Index = []int{i}
-	return
-}
-
-// TODO(gri): Should there be an error/bool indicator if the index
-//            is wrong for FieldByIndex?
-
-// FieldByIndex returns the nested field corresponding to index.
-func (t *structType) FieldByIndex(index []int) (f StructField) {
-	f.Type = toType(&t.rtype)
-	for i, x := range index {
-		if i > 0 {
-			ft := f.Type
-			if ft.Kind() == Pointer && ft.Elem().Kind() == Struct {
-				ft = ft.Elem()
-			}
-			f.Type = ft
-		}
-		f = f.Type.Field(x)
-	}
-	return
-}
-
-// A fieldScan represents an item on the fieldByNameFunc scan work list.
-type fieldScan struct {
-	typ   *structType
-	index []int
-}
-
-// FieldByNameFunc returns the struct field with a name that satisfies the
-// match function and a boolean to indicate if the field was found.
-func (t *structType) FieldByNameFunc(match func(string) bool) (result StructField, ok bool) {
-	// This uses the same condition that the Go language does: there must be a unique instance
-	// of the match at a given depth level. If there are multiple instances of a match at the
-	// same depth, they annihilate each other and inhibit any possible match at a lower level.
-	// The algorithm is breadth first search, one depth level at a time.
-
-	// The current and next slices are work queues:
-	// current lists the fields to visit on this depth level,
-	// and next lists the fields on the next lower level.
-	current := []fieldScan{}
-	next := []fieldScan{{typ: t}}
-
-	// nextCount records the number of times an embedded type has been
-	// encountered and considered for queueing in the 'next' slice.
-	// We only queue the first one, but we increment the count on each.
-	// If a struct type T can be reached more than once at a given depth level,
-	// then it annihilates itself and need not be considered at all when we
-	// process that next depth level.
-	var nextCount map[*structType]int
-
-	// visited records the structs that have been considered already.
-	// Embedded pointer fields can create cycles in the graph of
-	// reachable embedded types; visited avoids following those cycles.
-	// It also avoids duplicated effort: if we didn't find the field in an
-	// embedded type T at level 2, we won't find it in one at level 4 either.
-	visited := map[*structType]bool{}
-
-	for len(next) > 0 {
-		current, next = next, current[:0]
-		count := nextCount
-		nextCount = nil
-
-		// Process all the fields at this depth, now listed in 'current'.
-		// The loop queues embedded fields found in 'next', for processing during the next
-		// iteration. The multiplicity of the 'current' field counts is recorded
-		// in 'count'; the multiplicity of the 'next' field counts is recorded in 'nextCount'.
-		for _, scan := range current {
-			t := scan.typ
-			if visited[t] {
-				// We've looked through this type before, at a higher level.
-				// That higher level would shadow the lower level we're now at,
-				// so this one can't be useful to us. Ignore it.
-				continue
-			}
-			visited[t] = true
-			for i := range t.fields {
-				f := &t.fields[i]
-				// Find name and (for embedded field) type for field f.
-				fname := f.name.name()
-				var ntyp *rtype
-				if f.embedded() {
-					// Embedded field of type T or *T.
-					ntyp = f.typ
-					if ntyp.Kind() == Pointer {
-						ntyp = ntyp.Elem().common()
-					}
-				}
-
-				// Does it match?
-				if match(fname) {
-					// Potential match
-					if count[t] > 1 || ok {
-						// Name appeared multiple times at this level: annihilate.
-						return StructField{}, false
-					}
-					result = t.Field(i)
-					result.Index = nil
-					result.Index = append(result.Index, scan.index...)
-					result.Index = append(result.Index, i)
-					ok = true
-					continue
-				}
-
-				// Queue embedded struct fields for processing with next level,
-				// but only if we haven't seen a match yet at this level and only
-				// if the embedded types haven't already been queued.
-				if ok || ntyp == nil || ntyp.Kind() != Struct {
-					continue
-				}
-				styp := (*structType)(unsafe.Pointer(ntyp))
-				if nextCount[styp] > 0 {
-					nextCount[styp] = 2 // exact multiple doesn't matter
-					continue
-				}
-				if nextCount == nil {
-					nextCount = map[*structType]int{}
-				}
-				nextCount[styp] = 1
-				if count[t] > 1 {
-					nextCount[styp] = 2 // exact multiple doesn't matter
-				}
-				var index []int
-				index = append(index, scan.index...)
-				index = append(index, i)
-				next = append(next, fieldScan{styp, index})
-			}
-		}
-		if ok {
-			break
-		}
-	}
-	return
-}
-
-// FieldByName returns the struct field with the given name
-// and a boolean to indicate if the field was found.
-func (t *structType) FieldByName(name string) (f StructField, present bool) {
-	// Quick check for top-level name, or struct without embedded fields.
-	hasEmbeds := false
-	if name != "" {
-		for i := range t.fields {
-			tf := &t.fields[i]
-			if tf.name.name() == name {
-				return t.Field(i), true
-			}
-			if tf.embedded() {
-				hasEmbeds = true
-			}
-		}
-	}
-	if !hasEmbeds {
-		return
-	}
-	return t.FieldByNameFunc(func(s string) bool { return s == name })
-}
-
-// TypeOf returns the reflection Type that represents the dynamic type of i.
-// If i is a nil interface value, TypeOf returns nil.
-func TypeOf(i any) Type {
-	eface := *(*emptyInterface)(unsafe.Pointer(&i))
-	return toType(eface.typ)
-}
-
-// ptrMap is the cache for PointerTo.
-var ptrMap sync.Map // map[*rtype]*ptrType
-
-// PtrTo returns the pointer type with element t.
-// For example, if t represents type Foo, PtrTo(t) represents *Foo.
-//
-// PtrTo is the old spelling of PointerTo.
-// The two functions behave identically.
-func PtrTo(t Type) Type { return PointerTo(t) }
-
-// PointerTo returns the pointer type with element t.
-// For example, if t represents type Foo, PointerTo(t) represents *Foo.
-func PointerTo(t Type) Type {
-	return t.(*rtype).ptrTo()
-}
-
-func (t *rtype) ptrTo() *rtype {
-	if t.ptrToThis != 0 {
-		return t.typeOff(t.ptrToThis)
-	}
-
-	// Check the cache.
-	if pi, ok := ptrMap.Load(t); ok {
-		return &pi.(*ptrType).rtype
-	}
-
-	// Look in known types.
-	s := "*" + t.String()
-	for _, tt := range typesByString(s) {
-		p := (*ptrType)(unsafe.Pointer(tt))
-		if p.elem != t {
-			continue
-		}
-		pi, _ := ptrMap.LoadOrStore(t, p)
-		return &pi.(*ptrType).rtype
-	}
-
-	// Create a new ptrType starting with the description
-	// of an *unsafe.Pointer.
-	var iptr any = (*unsafe.Pointer)(nil)
-	prototype := *(**ptrType)(unsafe.Pointer(&iptr))
-	pp := *prototype
-
-	pp.str = resolveReflectName(newName(s, "", false))
-	pp.ptrToThis = 0
-
-	// For the type structures linked into the binary, the
-	// compiler provides a good hash of the string.
-	// Create a good hash for the new string by using
-	// the FNV-1 hash's mixing function to combine the
-	// old hash and the new "*".
-	pp.hash = fnv1(t.hash, '*')
-
-	pp.elem = t
-
-	pi, _ := ptrMap.LoadOrStore(t, &pp)
-	return &pi.(*ptrType).rtype
-}
-
-// fnv1 incorporates the list of bytes into the hash x using the FNV-1 hash function.
-func fnv1(x uint32, list ...byte) uint32 {
-	for _, b := range list {
-		x = x*16777619 ^ uint32(b)
-	}
-	return x
-}
-
-func (t *rtype) Implements(u Type) bool {
-	if u == nil {
-		panic("reflect: nil type passed to Type.Implements")
-	}
-	if u.Kind() != Interface {
-		panic("reflect: non-interface type passed to Type.Implements")
-	}
-	return implements(u.(*rtype), t)
-}
-
-func (t *rtype) AssignableTo(u Type) bool {
-	if u == nil {
-		panic("reflect: nil type passed to Type.AssignableTo")
-	}
-	uu := u.(*rtype)
-	return directlyAssignable(uu, t) || implements(uu, t)
-}
-
-func (t *rtype) ConvertibleTo(u Type) bool {
-	if u == nil {
-		panic("reflect: nil type passed to Type.ConvertibleTo")
-	}
-	uu := u.(*rtype)
-	return convertOp(uu, t) != nil
-}
-
-func (t *rtype) Comparable() bool {
-	return t.equal != nil
-}
-
-// implements reports whether the type V implements the interface type T.
-func implements(T, V *rtype) bool {
-	if T.Kind() != Interface {
-		return false
-	}
-	t := (*interfaceType)(unsafe.Pointer(T))
-	if len(t.methods) == 0 {
-		return true
-	}
-
-	// The same algorithm applies in both cases, but the
-	// method tables for an interface type and a concrete type
-	// are different, so the code is duplicated.
-	// In both cases the algorithm is a linear scan over the two
-	// lists - T's methods and V's methods - simultaneously.
-	// Since method tables are stored in a unique sorted order
-	// (alphabetical, with no duplicate method names), the scan
-	// through V's methods must hit a match for each of T's
-	// methods along the way, or else V does not implement T.
-	// This lets us run the scan in overall linear time instead of
-	// the quadratic time  a naive search would require.
-	// See also ../runtime/iface.go.
-	if V.Kind() == Interface {
-		v := (*interfaceType)(unsafe.Pointer(V))
-		i := 0
-		for j := 0; j < len(v.methods); j++ {
-			tm := &t.methods[i]
-			tmName := t.nameOff(tm.name)
-			vm := &v.methods[j]
-			vmName := V.nameOff(vm.name)
-			if vmName.name() == tmName.name() && V.typeOff(vm.typ) == t.typeOff(tm.typ) {
-				if !tmName.isExported() {
-					tmPkgPath := tmName.pkgPath()
-					if tmPkgPath == "" {
-						tmPkgPath = t.pkgPath.name()
-					}
-					vmPkgPath := vmName.pkgPath()
-					if vmPkgPath == "" {
-						vmPkgPath = v.pkgPath.name()
-					}
-					if tmPkgPath != vmPkgPath {
-						continue
-					}
-				}
-				if i++; i >= len(t.methods) {
-					return true
-				}
-			}
-		}
-		return false
-	}
-
-	v := V.uncommon()
-	if v == nil {
-		return false
-	}
-	i := 0
-	vmethods := v.methods()
-	for j := 0; j < int(v.mcount); j++ {
-		tm := &t.methods[i]
-		tmName := t.nameOff(tm.name)
-		vm := vmethods[j]
-		vmName := V.nameOff(vm.name)
-		if vmName.name() == tmName.name() && V.typeOff(vm.mtyp) == t.typeOff(tm.typ) {
-			if !tmName.isExported() {
-				tmPkgPath := tmName.pkgPath()
-				if tmPkgPath == "" {
-					tmPkgPath = t.pkgPath.name()
-				}
-				vmPkgPath := vmName.pkgPath()
-				if vmPkgPath == "" {
-					vmPkgPath = V.nameOff(v.pkgPath).name()
-				}
-				if tmPkgPath != vmPkgPath {
-					continue
-				}
-			}
-			if i++; i >= len(t.methods) {
-				return true
-			}
-		}
-	}
-	return false
-}
-
-// specialChannelAssignability reports whether a value x of channel type V
-// can be directly assigned (using memmove) to another channel type T.
-// https://golang.org/doc/go_spec.html#Assignability
-// T and V must be both of Chan kind.
-func specialChannelAssignability(T, V *rtype) bool {
-	// Special case:
-	// x is a bidirectional channel value, T is a channel type,
-	// x's type V and T have identical element types,
-	// and at least one of V or T is not a defined type.
-	return V.ChanDir() == BothDir && (T.Name() == "" || V.Name() == "") && haveIdenticalType(T.Elem(), V.Elem(), true)
-}
-
-// directlyAssignable reports whether a value x of type V can be directly
-// assigned (using memmove) to a value of type T.
-// https://golang.org/doc/go_spec.html#Assignability
-// Ignoring the interface rules (implemented elsewhere)
-// and the ideal constant rules (no ideal constants at run time).
-func directlyAssignable(T, V *rtype) bool {
-	// x's type V is identical to T?
-	if T == V {
-		return true
-	}
-
-	// Otherwise at least one of T and V must not be defined
-	// and they must have the same kind.
-	if T.hasName() && V.hasName() || T.Kind() != V.Kind() {
-		return false
-	}
-
-	if T.Kind() == Chan && specialChannelAssignability(T, V) {
-		return true
-	}
-
-	// x's type T and V must have identical underlying types.
-	return haveIdenticalUnderlyingType(T, V, true)
-}
-
-func haveIdenticalType(T, V Type, cmpTags bool) bool {
-	if cmpTags {
-		return T == V
-	}
-
-	if T.Name() != V.Name() || T.Kind() != V.Kind() || T.PkgPath() != V.PkgPath() {
-		return false
-	}
-
-	return haveIdenticalUnderlyingType(T.common(), V.common(), false)
-}
-
-func haveIdenticalUnderlyingType(T, V *rtype, cmpTags bool) bool {
-	if T == V {
-		return true
-	}
-
-	kind := T.Kind()
-	if kind != V.Kind() {
-		return false
-	}
-
-	// Non-composite types of equal kind have same underlying type
-	// (the predefined instance of the type).
-	if Bool <= kind && kind <= Complex128 || kind == String || kind == UnsafePointer {
-		return true
-	}
-
-	// Composite types.
-	switch kind {
-	case Array:
-		return T.Len() == V.Len() && haveIdenticalType(T.Elem(), V.Elem(), cmpTags)
-
-	case Chan:
-		return V.ChanDir() == T.ChanDir() && haveIdenticalType(T.Elem(), V.Elem(), cmpTags)
-
-	case Func:
-		t := (*funcType)(unsafe.Pointer(T))
-		v := (*funcType)(unsafe.Pointer(V))
-		if t.outCount != v.outCount || t.inCount != v.inCount {
-			return false
-		}
-		for i := 0; i < t.NumIn(); i++ {
-			if !haveIdenticalType(t.In(i), v.In(i), cmpTags) {
-				return false
-			}
-		}
-		for i := 0; i < t.NumOut(); i++ {
-			if !haveIdenticalType(t.Out(i), v.Out(i), cmpTags) {
-				return false
-			}
-		}
-		return true
-
-	case Interface:
-		t := (*interfaceType)(unsafe.Pointer(T))
-		v := (*interfaceType)(unsafe.Pointer(V))
-		if len(t.methods) == 0 && len(v.methods) == 0 {
-			return true
-		}
-		// Might have the same methods but still
-		// need a run time conversion.
-		return false
-
-	case Map:
-		return haveIdenticalType(T.Key(), V.Key(), cmpTags) && haveIdenticalType(T.Elem(), V.Elem(), cmpTags)
-
-	case Pointer, Slice:
-		return haveIdenticalType(T.Elem(), V.Elem(), cmpTags)
-
-	case Struct:
-		t := (*structType)(unsafe.Pointer(T))
-		v := (*structType)(unsafe.Pointer(V))
-		if len(t.fields) != len(v.fields) {
-			return false
-		}
-		if t.pkgPath.name() != v.pkgPath.name() {
-			return false
-		}
-		for i := range t.fields {
-			tf := &t.fields[i]
-			vf := &v.fields[i]
-			if tf.name.name() != vf.name.name() {
-				return false
-			}
-			if !haveIdenticalType(tf.typ, vf.typ, cmpTags) {
-				return false
-			}
-			if cmpTags && tf.name.tag() != vf.name.tag() {
-				return false
-			}
-			if tf.offsetEmbed != vf.offsetEmbed {
-				return false
-			}
-		}
-		return true
-	}
-
-	return false
-}
-
-// typelinks is implemented in package runtime.
-// It returns a slice of the sections in each module,
-// and a slice of *rtype offsets in each module.
-//
-// The types in each module are sorted by string. That is, the first
-// two linked types of the first module are:
-//
-//	d0 := sections[0]
-//	t1 := (*rtype)(add(d0, offset[0][0]))
-//	t2 := (*rtype)(add(d0, offset[0][1]))
-//
-// and
-//
-//	t1.String() < t2.String()
-//
-// Note that strings are not unique identifiers for types:
-// there can be more than one with a given string.
-// Only types we might want to look up are included:
-// pointers, channels, maps, slices, and arrays.
-func typelinks() (sections []unsafe.Pointer, offset [][]int32)
-
-func rtypeOff(section unsafe.Pointer, off int32) *rtype {
-	return (*rtype)(add(section, uintptr(off), "sizeof(rtype) > 0"))
-}
-
-// typesByString returns the subslice of typelinks() whose elements have
-// the given string representation.
-// It may be empty (no known types with that string) or may have
-// multiple elements (multiple types with that string).
-func typesByString(s string) []*rtype {
-	sections, offset := typelinks()
-	var ret []*rtype
-
-	for offsI, offs := range offset {
-		section := sections[offsI]
-
-		// We are looking for the first index i where the string becomes >= s.
-		// This is a copy of sort.Search, with f(h) replaced by (*typ[h].String() >= s).
-		i, j := 0, len(offs)
-		for i < j {
-			h := i + (j-i)>>1 // avoid overflow when computing h
-			// i ≤ h < j
-			if !(rtypeOff(section, offs[h]).String() >= s) {
-				i = h + 1 // preserves f(i-1) == false
-			} else {
-				j = h // preserves f(j) == true
-			}
-		}
-		// i == j, f(i-1) == false, and f(j) (= f(i)) == true  =>  answer is i.
-
-		// Having found the first, linear scan forward to find the last.
-		// We could do a second binary search, but the caller is going
-		// to do a linear scan anyway.
-		for j := i; j < len(offs); j++ {
-			typ := rtypeOff(section, offs[j])
-			if typ.String() != s {
-				break
-			}
-			ret = append(ret, typ)
-		}
-	}
-	return ret
-}
-
-// The lookupCache caches ArrayOf, ChanOf, MapOf and SliceOf lookups.
-var lookupCache sync.Map // map[cacheKey]*rtype
-
-// A cacheKey is the key for use in the lookupCache.
-// Four values describe any of the types we are looking for:
-// type kind, one or two subtypes, and an extra integer.
-type cacheKey struct {
-	kind  Kind
-	t1    *rtype
-	t2    *rtype
-	extra uintptr
-}
-
-// The funcLookupCache caches FuncOf lookups.
-// FuncOf does not share the common lookupCache since cacheKey is not
-// sufficient to represent functions unambiguously.
-var funcLookupCache struct {
-	sync.Mutex // Guards stores (but not loads) on m.
-
-	// m is a map[uint32][]*rtype keyed by the hash calculated in FuncOf.
-	// Elements of m are append-only and thus safe for concurrent reading.
-	m sync.Map
-}
-
-// ChanOf returns the channel type with the given direction and element type.
-// For example, if t represents int, ChanOf(RecvDir, t) represents <-chan int.
-//
-// The gc runtime imposes a limit of 64 kB on channel element types.
-// If t's size is equal to or exceeds this limit, ChanOf panics.
-func ChanOf(dir ChanDir, t Type) Type {
-	typ := t.(*rtype)
-
-	// Look in cache.
-	ckey := cacheKey{Chan, typ, nil, uintptr(dir)}
-	if ch, ok := lookupCache.Load(ckey); ok {
-		return ch.(*rtype)
-	}
-
-	// This restriction is imposed by the gc compiler and the runtime.
-	if typ.size >= 1<<16 {
-		panic("reflect.ChanOf: element size too large")
-	}
-
-	// Look in known types.
-	var s string
-	switch dir {
-	default:
-		panic("reflect.ChanOf: invalid dir")
-	case SendDir:
-		s = "chan<- " + typ.String()
-	case RecvDir:
-		s = "<-chan " + typ.String()
-	case BothDir:
-		typeStr := typ.String()
-		if typeStr[0] == '<' {
-			// typ is recv chan, need parentheses as "<-" associates with leftmost
-			// chan possible, see:
-			// * https://golang.org/ref/spec#Channel_types
-			// * https://github.com/golang/go/issues/39897
-			s = "chan (" + typeStr + ")"
-		} else {
-			s = "chan " + typeStr
-		}
-	}
-	for _, tt := range typesByString(s) {
-		ch := (*chanType)(unsafe.Pointer(tt))
-		if ch.elem == typ && ch.dir == uintptr(dir) {
-			ti, _ := lookupCache.LoadOrStore(ckey, tt)
-			return ti.(Type)
-		}
-	}
-
-	// Make a channel type.
-	var ichan any = (chan unsafe.Pointer)(nil)
-	prototype := *(**chanType)(unsafe.Pointer(&ichan))
-	ch := *prototype
-	ch.tflag = tflagRegularMemory
-	ch.dir = uintptr(dir)
-	ch.str = resolveReflectName(newName(s, "", false))
-	ch.hash = fnv1(typ.hash, 'c', byte(dir))
-	ch.elem = typ
-
-	ti, _ := lookupCache.LoadOrStore(ckey, &ch.rtype)
-	return ti.(Type)
-}
-
-// MapOf returns the map type with the given key and element types.
-// For example, if k represents int and e represents string,
-// MapOf(k, e) represents map[int]string.
-//
-// If the key type is not a valid map key type (that is, if it does
-// not implement Go's == operator), MapOf panics.
-func MapOf(key, elem Type) Type {
-	ktyp := key.(*rtype)
-	etyp := elem.(*rtype)
-
-	if ktyp.equal == nil {
-		panic("reflect.MapOf: invalid key type " + ktyp.String())
-	}
-
-	// Look in cache.
-	ckey := cacheKey{Map, ktyp, etyp, 0}
-	if mt, ok := lookupCache.Load(ckey); ok {
-		return mt.(Type)
-	}
-
-	// Look in known types.
-	s := "map[" + ktyp.String() + "]" + etyp.String()
-	for _, tt := range typesByString(s) {
-		mt := (*mapType)(unsafe.Pointer(tt))
-		if mt.key == ktyp && mt.elem == etyp {
-			ti, _ := lookupCache.LoadOrStore(ckey, tt)
-			return ti.(Type)
-		}
-	}
-
-	// Make a map type.
-	// Note: flag values must match those used in the TMAP case
-	// in ../cmd/compile/internal/reflectdata/reflect.go:writeType.
-	var imap any = (map[unsafe.Pointer]unsafe.Pointer)(nil)
-	mt := **(**mapType)(unsafe.Pointer(&imap))
-	mt.str = resolveReflectName(newName(s, "", false))
-	mt.tflag = 0
-	mt.hash = fnv1(etyp.hash, 'm', byte(ktyp.hash>>24), byte(ktyp.hash>>16), byte(ktyp.hash>>8), byte(ktyp.hash))
-	mt.key = ktyp
-	mt.elem = etyp
-	mt.bucket = bucketOf(ktyp, etyp)
-	mt.hasher = func(p unsafe.Pointer, seed uintptr) uintptr {
-		return typehash(ktyp, p, seed)
-	}
-	mt.flags = 0
-	if ktyp.size > maxKeySize {
-		mt.keysize = uint8(goarch.PtrSize)
-		mt.flags |= 1 // indirect key
-	} else {
-		mt.keysize = uint8(ktyp.size)
-	}
-	if etyp.size > maxValSize {
-		mt.valuesize = uint8(goarch.PtrSize)
-		mt.flags |= 2 // indirect value
-	} else {
-		mt.valuesize = uint8(etyp.size)
-	}
-	mt.bucketsize = uint16(mt.bucket.size)
-	if isReflexive(ktyp) {
-		mt.flags |= 4
-	}
-	if needKeyUpdate(ktyp) {
-		mt.flags |= 8
-	}
-	if hashMightPanic(ktyp) {
-		mt.flags |= 16
-	}
-	mt.ptrToThis = 0
-
-	ti, _ := lookupCache.LoadOrStore(ckey, &mt.rtype)
-	return ti.(Type)
-}
-
-// TODO(crawshaw): as these funcTypeFixedN structs have no methods,
-// they could be defined at runtime using the StructOf function.
-type funcTypeFixed4 struct {
-	funcType
-	args [4]*rtype
-}
-type funcTypeFixed8 struct {
-	funcType
-	args [8]*rtype
-}
-type funcTypeFixed16 struct {
-	funcType
-	args [16]*rtype
-}
-type funcTypeFixed32 struct {
-	funcType
-	args [32]*rtype
-}
-type funcTypeFixed64 struct {
-	funcType
-	args [64]*rtype
-}
-type funcTypeFixed128 struct {
-	funcType
-	args [128]*rtype
-}
-
-// FuncOf returns the function type with the given argument and result types.
-// For example if k represents int and e represents string,
-// FuncOf([]Type{k}, []Type{e}, false) represents func(int) string.
-//
-// The variadic argument controls whether the function is variadic. FuncOf
-// panics if the in[len(in)-1] does not represent a slice and variadic is
-// true.
-func FuncOf(in, out []Type, variadic bool) Type {
-	if variadic && (len(in) == 0 || in[len(in)-1].Kind() != Slice) {
-		panic("reflect.FuncOf: last arg of variadic func must be slice")
-	}
-
-	// Make a func type.
-	var ifunc any = (func())(nil)
-	prototype := *(**funcType)(unsafe.Pointer(&ifunc))
-	n := len(in) + len(out)
-
-	var ft *funcType
-	var args []*rtype
-	switch {
-	case n <= 4:
-		fixed := new(funcTypeFixed4)
-		args = fixed.args[:0:len(fixed.args)]
-		ft = &fixed.funcType
-	case n <= 8:
-		fixed := new(funcTypeFixed8)
-		args = fixed.args[:0:len(fixed.args)]
-		ft = &fixed.funcType
-	case n <= 16:
-		fixed := new(funcTypeFixed16)
-		args = fixed.args[:0:len(fixed.args)]
-		ft = &fixed.funcType
-	case n <= 32:
-		fixed := new(funcTypeFixed32)
-		args = fixed.args[:0:len(fixed.args)]
-		ft = &fixed.funcType
-	case n <= 64:
-		fixed := new(funcTypeFixed64)
-		args = fixed.args[:0:len(fixed.args)]
-		ft = &fixed.funcType
-	case n <= 128:
-		fixed := new(funcTypeFixed128)
-		args = fixed.args[:0:len(fixed.args)]
-		ft = &fixed.funcType
-	default:
-		panic("reflect.FuncOf: too many arguments")
-	}
-	*ft = *prototype
-
-	// Build a hash and minimally populate ft.
-	var hash uint32
-	for _, in := range in {
-		t := in.(*rtype)
-		args = append(args, t)
-		hash = fnv1(hash, byte(t.hash>>24), byte(t.hash>>16), byte(t.hash>>8), byte(t.hash))
-	}
-	if variadic {
-		hash = fnv1(hash, 'v')
-	}
-	hash = fnv1(hash, '.')
-	for _, out := range out {
-		t := out.(*rtype)
-		args = append(args, t)
-		hash = fnv1(hash, byte(t.hash>>24), byte(t.hash>>16), byte(t.hash>>8), byte(t.hash))
-	}
-	if len(args) > 50 {
-		panic("reflect.FuncOf does not support more than 50 arguments")
-	}
-	ft.tflag = 0
-	ft.hash = hash
-	ft.inCount = uint16(len(in))
-	ft.outCount = uint16(len(out))
-	if variadic {
-		ft.outCount |= 1 << 15
-	}
-
-	// Look in cache.
-	if ts, ok := funcLookupCache.m.Load(hash); ok {
-		for _, t := range ts.([]*rtype) {
-			if haveIdenticalUnderlyingType(&ft.rtype, t, true) {
-				return t
-			}
-		}
-	}
-
-	// Not in cache, lock and retry.
-	funcLookupCache.Lock()
-	defer funcLookupCache.Unlock()
-	if ts, ok := funcLookupCache.m.Load(hash); ok {
-		for _, t := range ts.([]*rtype) {
-			if haveIdenticalUnderlyingType(&ft.rtype, t, true) {
-				return t
-			}
-		}
-	}
-
-	addToCache := func(tt *rtype) Type {
-		var rts []*rtype
-		if rti, ok := funcLookupCache.m.Load(hash); ok {
-			rts = rti.([]*rtype)
-		}
-		funcLookupCache.m.Store(hash, append(rts, tt))
-		return tt
-	}
-
-	// Look in known types for the same string representation.
-	str := funcStr(ft)
-	for _, tt := range typesByString(str) {
-		if haveIdenticalUnderlyingType(&ft.rtype, tt, true) {
-			return addToCache(tt)
-		}
-	}
-
-	// Populate the remaining fields of ft and store in cache.
-	ft.str = resolveReflectName(newName(str, "", false))
-	ft.ptrToThis = 0
-	return addToCache(&ft.rtype)
-}
-
-// funcStr builds a string representation of a funcType.
-func funcStr(ft *funcType) string {
-	repr := make([]byte, 0, 64)
-	repr = append(repr, "func("...)
-	for i, t := range ft.in() {
-		if i > 0 {
-			repr = append(repr, ", "...)
-		}
-		if ft.IsVariadic() && i == int(ft.inCount)-1 {
-			repr = append(repr, "..."...)
-			repr = append(repr, (*sliceType)(unsafe.Pointer(t)).elem.String()...)
-		} else {
-			repr = append(repr, t.String()...)
-		}
-	}
-	repr = append(repr, ')')
-	out := ft.out()
-	if len(out) == 1 {
-		repr = append(repr, ' ')
-	} else if len(out) > 1 {
-		repr = append(repr, " ("...)
-	}
-	for i, t := range out {
-		if i > 0 {
-			repr = append(repr, ", "...)
-		}
-		repr = append(repr, t.String()...)
-	}
-	if len(out) > 1 {
-		repr = append(repr, ')')
-	}
-	return string(repr)
-}
-
-// isReflexive reports whether the == operation on the type is reflexive.
-// That is, x == x for all values x of type t.
-func isReflexive(t *rtype) bool {
-	switch t.Kind() {
-	case Bool, Int, Int8, Int16, Int32, Int64, Uint, Uint8, Uint16, Uint32, Uint64, Uintptr, Chan, Pointer, String, UnsafePointer:
-		return true
-	case Float32, Float64, Complex64, Complex128, Interface:
-		return false
-	case Array:
-		tt := (*arrayType)(unsafe.Pointer(t))
-		return isReflexive(tt.elem)
-	case Struct:
-		tt := (*structType)(unsafe.Pointer(t))
-		for _, f := range tt.fields {
-			if !isReflexive(f.typ) {
-				return false
-			}
-		}
-		return true
-	default:
-		// Func, Map, Slice, Invalid
-		panic("isReflexive called on non-key type " + t.String())
-	}
-}
-
-// needKeyUpdate reports whether map overwrites require the key to be copied.
-func needKeyUpdate(t *rtype) bool {
-	switch t.Kind() {
-	case Bool, Int, Int8, Int16, Int32, Int64, Uint, Uint8, Uint16, Uint32, Uint64, Uintptr, Chan, Pointer, UnsafePointer:
-		return false
-	case Float32, Float64, Complex64, Complex128, Interface, String:
-		// Float keys can be updated from +0 to -0.
-		// String keys can be updated to use a smaller backing store.
-		// Interfaces might have floats of strings in them.
-		return true
-	case Array:
-		tt := (*arrayType)(unsafe.Pointer(t))
-		return needKeyUpdate(tt.elem)
-	case Struct:
-		tt := (*structType)(unsafe.Pointer(t))
-		for _, f := range tt.fields {
-			if needKeyUpdate(f.typ) {
-				return true
-			}
-		}
-		return false
-	default:
-		// Func, Map, Slice, Invalid
-		panic("needKeyUpdate called on non-key type " + t.String())
-	}
-}
-
-// hashMightPanic reports whether the hash of a map key of type t might panic.
-func hashMightPanic(t *rtype) bool {
-	switch t.Kind() {
-	case Interface:
-		return true
-	case Array:
-		tt := (*arrayType)(unsafe.Pointer(t))
-		return hashMightPanic(tt.elem)
-	case Struct:
-		tt := (*structType)(unsafe.Pointer(t))
-		for _, f := range tt.fields {
-			if hashMightPanic(f.typ) {
-				return true
-			}
-		}
-		return false
-	default:
-		return false
-	}
-}
-
-// Make sure these routines stay in sync with ../../runtime/map.go!
-// These types exist only for GC, so we only fill out GC relevant info.
-// Currently, that's just size and the GC program. We also fill in string
-// for possible debugging use.
-const (
-	bucketSize uintptr = 8
-	maxKeySize uintptr = 128
-	maxValSize uintptr = 128
-)
-
-func bucketOf(ktyp, etyp *rtype) *rtype {
-	if ktyp.size > maxKeySize {
-		ktyp = PointerTo(ktyp).(*rtype)
-	}
-	if etyp.size > maxValSize {
-		etyp = PointerTo(etyp).(*rtype)
-	}
-
-	// Prepare GC data if any.
-	// A bucket is at most bucketSize*(1+maxKeySize+maxValSize)+2*ptrSize bytes,
-	// or 2072 bytes, or 259 pointer-size words, or 33 bytes of pointer bitmap.
-	// Note that since the key and value are known to be <= 128 bytes,
-	// they're guaranteed to have bitmaps instead of GC programs.
-	var gcdata *byte
-	var ptrdata uintptr
-	var overflowPad uintptr
-
-	size := bucketSize*(1+ktyp.size+etyp.size) + overflowPad + goarch.PtrSize
-	if size&uintptr(ktyp.align-1) != 0 || size&uintptr(etyp.align-1) != 0 {
-		panic("reflect: bad size computation in MapOf")
-	}
-
-	if ktyp.ptrdata != 0 || etyp.ptrdata != 0 {
-		nptr := (bucketSize*(1+ktyp.size+etyp.size) + goarch.PtrSize) / goarch.PtrSize
-		mask := make([]byte, (nptr+7)/8)
-		base := bucketSize / goarch.PtrSize
-
-		if ktyp.ptrdata != 0 {
-			emitGCMask(mask, base, ktyp, bucketSize)
-		}
-		base += bucketSize * ktyp.size / goarch.PtrSize
-
-		if etyp.ptrdata != 0 {
-			emitGCMask(mask, base, etyp, bucketSize)
-		}
-		base += bucketSize * etyp.size / goarch.PtrSize
-		base += overflowPad / goarch.PtrSize
-
-		word := base
-		mask[word/8] |= 1 << (word % 8)
-		gcdata = &mask[0]
-		ptrdata = (word + 1) * goarch.PtrSize
-
-		// overflow word must be last
-		if ptrdata != size {
-			panic("reflect: bad layout computation in MapOf")
-		}
-	}
-
-	b := &rtype{
-		align:   goarch.PtrSize,
-		size:    size,
-		kind:    uint8(Struct),
-		ptrdata: ptrdata,
-		gcdata:  gcdata,
-	}
-	if overflowPad > 0 {
-		b.align = 8
-	}
-	s := "bucket(" + ktyp.String() + "," + etyp.String() + ")"
-	b.str = resolveReflectName(newName(s, "", false))
-	return b
-}
-
-func (t *rtype) gcSlice(begin, end uintptr) []byte {
-	return (*[1 << 30]byte)(unsafe.Pointer(t.gcdata))[begin:end:end]
-}
-
-// emitGCMask writes the GC mask for [n]typ into out, starting at bit
-// offset base.
-func emitGCMask(out []byte, base uintptr, typ *rtype, n uintptr) {
-	if typ.kind&kindGCProg != 0 {
-		panic("reflect: unexpected GC program")
-	}
-	ptrs := typ.ptrdata / goarch.PtrSize
-	words := typ.size / goarch.PtrSize
-	mask := typ.gcSlice(0, (ptrs+7)/8)
-	for j := uintptr(0); j < ptrs; j++ {
-		if (mask[j/8]>>(j%8))&1 != 0 {
-			for i := uintptr(0); i < n; i++ {
-				k := base + i*words + j
-				out[k/8] |= 1 << (k % 8)
-			}
-		}
-	}
-}
-
-// appendGCProg appends the GC program for the first ptrdata bytes of
-// typ to dst and returns the extended slice.
-func appendGCProg(dst []byte, typ *rtype) []byte {
-	if typ.kind&kindGCProg != 0 {
-		// Element has GC program; emit one element.
-		n := uintptr(*(*uint32)(unsafe.Pointer(typ.gcdata)))
-		prog := typ.gcSlice(4, 4+n-1)
-		return append(dst, prog...)
-	}
-
-	// Element is small with pointer mask; use as literal bits.
-	ptrs := typ.ptrdata / goarch.PtrSize
-	mask := typ.gcSlice(0, (ptrs+7)/8)
-
-	// Emit 120-bit chunks of full bytes (max is 127 but we avoid using partial bytes).
-	for ; ptrs > 120; ptrs -= 120 {
-		dst = append(dst, 120)
-		dst = append(dst, mask[:15]...)
-		mask = mask[15:]
-	}
-
-	dst = append(dst, byte(ptrs))
-	dst = append(dst, mask...)
-	return dst
-}
-
-// SliceOf returns the slice type with element type t.
-// For example, if t represents int, SliceOf(t) represents []int.
-func SliceOf(t Type) Type {
-	typ := t.(*rtype)
-
-	// Look in cache.
-	ckey := cacheKey{Slice, typ, nil, 0}
-	if slice, ok := lookupCache.Load(ckey); ok {
-		return slice.(Type)
-	}
-
-	// Look in known types.
-	s := "[]" + typ.String()
-	for _, tt := range typesByString(s) {
-		slice := (*sliceType)(unsafe.Pointer(tt))
-		if slice.elem == typ {
-			ti, _ := lookupCache.LoadOrStore(ckey, tt)
-			return ti.(Type)
-		}
-	}
-
-	// Make a slice type.
-	var islice any = ([]unsafe.Pointer)(nil)
-	prototype := *(**sliceType)(unsafe.Pointer(&islice))
-	slice := *prototype
-	slice.tflag = 0
-	slice.str = resolveReflectName(newName(s, "", false))
-	slice.hash = fnv1(typ.hash, '[')
-	slice.elem = typ
-	slice.ptrToThis = 0
-
-	ti, _ := lookupCache.LoadOrStore(ckey, &slice.rtype)
-	return ti.(Type)
-}
-
-// The structLookupCache caches StructOf lookups.
-// StructOf does not share the common lookupCache since we need to pin
-// the memory associated with *structTypeFixedN.
-var structLookupCache struct {
-	sync.Mutex // Guards stores (but not loads) on m.
-
-	// m is a map[uint32][]Type keyed by the hash calculated in StructOf.
-	// Elements in m are append-only and thus safe for concurrent reading.
-	m sync.Map
-}
-
-type structTypeUncommon struct {
-	structType
-	u uncommonType
-}
-
-// isLetter reports whether a given 'rune' is classified as a Letter.
-func isLetter(ch rune) bool {
-	return 'a' <= ch && ch <= 'z' || 'A' <= ch && ch <= 'Z' || ch == '_' || ch >= utf8.RuneSelf && unicode.IsLetter(ch)
-}
-
-// isValidFieldName checks if a string is a valid (struct) field name or not.
-//
-// According to the language spec, a field name should be an identifier.
-//
-// identifier = letter { letter | unicode_digit } .
-// letter = unicode_letter | "_" .
-func isValidFieldName(fieldName string) bool {
-	for i, c := range fieldName {
-		if i == 0 && !isLetter(c) {
-			return false
-		}
-
-		if !(isLetter(c) || unicode.IsDigit(c)) {
-			return false
-		}
-	}
-
-	return len(fieldName) > 0
-}
-
-// StructOf returns the struct type containing fields.
-// The Offset and Index fields are ignored and computed as they would be
-// by the compiler.
-//
-// StructOf currently does not generate wrapper methods for embedded
-// fields and panics if passed unexported StructFields.
-// These limitations may be lifted in a future version.
-func StructOf(fields []StructField) Type {
-	var (
-		hash       = fnv1(0, []byte("struct {")...)
-		size       uintptr
-		typalign   uint8
-		comparable = true
-		methods    []method
-
-		fs   = make([]structField, len(fields))
-		repr = make([]byte, 0, 64)
-		fset = map[string]struct{}{} // fields' names
-
-		hasGCProg = false // records whether a struct-field type has a GCProg
-	)
-
-	lastzero := uintptr(0)
-	repr = append(repr, "struct {"...)
-	pkgpath := ""
-	for i, field := range fields {
-		if field.Name == "" {
-			panic("reflect.StructOf: field " + strconv.Itoa(i) + " has no name")
-		}
-		if !isValidFieldName(field.Name) {
-			panic("reflect.StructOf: field " + strconv.Itoa(i) + " has invalid name")
-		}
-		if field.Type == nil {
-			panic("reflect.StructOf: field " + strconv.Itoa(i) + " has no type")
-		}
-		f, fpkgpath := runtimeStructField(field)
-		ft := f.typ
-		if ft.kind&kindGCProg != 0 {
-			hasGCProg = true
-		}
-		if fpkgpath != "" {
-			if pkgpath == "" {
-				pkgpath = fpkgpath
-			} else if pkgpath != fpkgpath {
-				panic("reflect.Struct: fields with different PkgPath " + pkgpath + " and " + fpkgpath)
-			}
-		}
-
-		// Update string and hash
-		name := f.name.name()
-		hash = fnv1(hash, []byte(name)...)
-		repr = append(repr, (" " + name)...)
-		if f.embedded() {
-			// Embedded field
-			if f.typ.Kind() == Pointer {
-				// Embedded ** and *interface{} are illegal
-				elem := ft.Elem()
-				if k := elem.Kind(); k == Pointer || k == Interface {
-					panic("reflect.StructOf: illegal embedded field type " + ft.String())
-				}
-			}
-
-			switch f.typ.Kind() {
-			case Interface:
-				ift := (*interfaceType)(unsafe.Pointer(ft))
-				for im, m := range ift.methods {
-					if ift.nameOff(m.name).pkgPath() != "" {
-						// TODO(sbinet).  Issue 15924.
-						panic("reflect: embedded interface with unexported method(s) not implemented")
-					}
-
-					var (
-						mtyp    = ift.typeOff(m.typ)
-						ifield  = i
-						imethod = im
-						ifn     Value
-						tfn     Value
-					)
-
-					if ft.kind&kindDirectIface != 0 {
-						tfn = MakeFunc(mtyp, func(in []Value) []Value {
-							var args []Value
-							var recv = in[0]
-							if len(in) > 1 {
-								args = in[1:]
-							}
-							return recv.Field(ifield).Method(imethod).Call(args)
-						})
-						ifn = MakeFunc(mtyp, func(in []Value) []Value {
-							var args []Value
-							var recv = in[0]
-							if len(in) > 1 {
-								args = in[1:]
-							}
-							return recv.Field(ifield).Method(imethod).Call(args)
-						})
-					} else {
-						tfn = MakeFunc(mtyp, func(in []Value) []Value {
-							var args []Value
-							var recv = in[0]
-							if len(in) > 1 {
-								args = in[1:]
-							}
-							return recv.Field(ifield).Method(imethod).Call(args)
-						})
-						ifn = MakeFunc(mtyp, func(in []Value) []Value {
-							var args []Value
-							var recv = Indirect(in[0])
-							if len(in) > 1 {
-								args = in[1:]
-							}
-							return recv.Field(ifield).Method(imethod).Call(args)
-						})
-					}
-
-					methods = append(methods, method{
-						name: resolveReflectName(ift.nameOff(m.name)),
-						mtyp: resolveReflectType(mtyp),
-						ifn:  resolveReflectText(unsafe.Pointer(&ifn)),
-						tfn:  resolveReflectText(unsafe.Pointer(&tfn)),
-					})
-				}
-			case Pointer:
-				ptr := (*ptrType)(unsafe.Pointer(ft))
-				if unt := ptr.uncommon(); unt != nil {
-					if i > 0 && unt.mcount > 0 {
-						// Issue 15924.
-						panic("reflect: embedded type with methods not implemented if type is not first field")
-					}
-					if len(fields) > 1 {
-						panic("reflect: embedded type with methods not implemented if there is more than one field")
-					}
-					for _, m := range unt.methods() {
-						mname := ptr.nameOff(m.name)
-						if mname.pkgPath() != "" {
-							// TODO(sbinet).
-							// Issue 15924.
-							panic("reflect: embedded interface with unexported method(s) not implemented")
-						}
-						methods = append(methods, method{
-							name: resolveReflectName(mname),
-							mtyp: resolveReflectType(ptr.typeOff(m.mtyp)),
-							ifn:  resolveReflectText(ptr.textOff(m.ifn)),
-							tfn:  resolveReflectText(ptr.textOff(m.tfn)),
-						})
-					}
-				}
-				if unt := ptr.elem.uncommon(); unt != nil {
-					for _, m := range unt.methods() {
-						mname := ptr.nameOff(m.name)
-						if mname.pkgPath() != "" {
-							// TODO(sbinet)
-							// Issue 15924.
-							panic("reflect: embedded interface with unexported method(s) not implemented")
-						}
-						methods = append(methods, method{
-							name: resolveReflectName(mname),
-							mtyp: resolveReflectType(ptr.elem.typeOff(m.mtyp)),
-							ifn:  resolveReflectText(ptr.elem.textOff(m.ifn)),
-							tfn:  resolveReflectText(ptr.elem.textOff(m.tfn)),
-						})
-					}
-				}
-			default:
-				if unt := ft.uncommon(); unt != nil {
-					if i > 0 && unt.mcount > 0 {
-						// Issue 15924.
-						panic("reflect: embedded type with methods not implemented if type is not first field")
-					}
-					if len(fields) > 1 && ft.kind&kindDirectIface != 0 {
-						panic("reflect: embedded type with methods not implemented for non-pointer type")
-					}
-					for _, m := range unt.methods() {
-						mname := ft.nameOff(m.name)
-						if mname.pkgPath() != "" {
-							// TODO(sbinet)
-							// Issue 15924.
-							panic("reflect: embedded interface with unexported method(s) not implemented")
-						}
-						methods = append(methods, method{
-							name: resolveReflectName(mname),
-							mtyp: resolveReflectType(ft.typeOff(m.mtyp)),
-							ifn:  resolveReflectText(ft.textOff(m.ifn)),
-							tfn:  resolveReflectText(ft.textOff(m.tfn)),
-						})
-
-					}
-				}
-			}
-		}
-		if _, dup := fset[name]; dup && name != "_" {
-			panic("reflect.StructOf: duplicate field " + name)
-		}
-		fset[name] = struct{}{}
-
-		hash = fnv1(hash, byte(ft.hash>>24), byte(ft.hash>>16), byte(ft.hash>>8), byte(ft.hash))
-
-		repr = append(repr, (" " + ft.String())...)
-		if f.name.hasTag() {
-			hash = fnv1(hash, []byte(f.name.tag())...)
-			repr = append(repr, (" " + strconv.Quote(f.name.tag()))...)
-		}
-		if i < len(fields)-1 {
-			repr = append(repr, ';')
-		}
-
-		comparable = comparable && (ft.equal != nil)
-
-		offset := align(size, uintptr(ft.align))
-		if ft.align > typalign {
-			typalign = ft.align
-		}
-		size = offset + ft.size
-		f.offsetEmbed |= offset << 1
-
-		if ft.size == 0 {
-			lastzero = size
-		}
-
-		fs[i] = f
-	}
-
-	if size > 0 && lastzero == size {
-		// This is a non-zero sized struct that ends in a
-		// zero-sized field. We add an extra byte of padding,
-		// to ensure that taking the address of the final
-		// zero-sized field can't manufacture a pointer to the
-		// next object in the heap. See issue 9401.
-		size++
-	}
-
-	var typ *structType
-	var ut *uncommonType
-
-	if len(methods) == 0 {
-		t := new(structTypeUncommon)
-		typ = &t.structType
-		ut = &t.u
-	} else {
-		// A *rtype representing a struct is followed directly in memory by an
-		// array of method objects representing the methods attached to the
-		// struct. To get the same layout for a run time generated type, we
-		// need an array directly following the uncommonType memory.
-		// A similar strategy is used for funcTypeFixed4, ...funcTypeFixedN.
-		tt := New(StructOf([]StructField{
-			{Name: "S", Type: TypeOf(structType{})},
-			{Name: "U", Type: TypeOf(uncommonType{})},
-			{Name: "M", Type: ArrayOf(len(methods), TypeOf(methods[0]))},
-		}))
-
-		typ = (*structType)(tt.Elem().Field(0).Addr().UnsafePointer())
-		ut = (*uncommonType)(tt.Elem().Field(1).Addr().UnsafePointer())
-
-		copy(tt.Elem().Field(2).Slice(0, len(methods)).Interface().([]method), methods)
-	}
-	// TODO(sbinet): Once we allow embedding multiple types,
-	// methods will need to be sorted like the compiler does.
-	// TODO(sbinet): Once we allow non-exported methods, we will
-	// need to compute xcount as the number of exported methods.
-	ut.mcount = uint16(len(methods))
-	ut.xcount = ut.mcount
-	ut.moff = uint32(unsafe.Sizeof(uncommonType{}))
-
-	if len(fs) > 0 {
-		repr = append(repr, ' ')
-	}
-	repr = append(repr, '}')
-	hash = fnv1(hash, '}')
-	str := string(repr)
-
-	// Round the size up to be a multiple of the alignment.
-	size = align(size, uintptr(typalign))
-
-	// Make the struct type.
-	var istruct any = struct{}{}
-	prototype := *(**structType)(unsafe.Pointer(&istruct))
-	*typ = *prototype
-	typ.fields = fs
-	if pkgpath != "" {
-		typ.pkgPath = newName(pkgpath, "", false)
-	}
-
-	// Look in cache.
-	if ts, ok := structLookupCache.m.Load(hash); ok {
-		for _, st := range ts.([]Type) {
-			t := st.common()
-			if haveIdenticalUnderlyingType(&typ.rtype, t, true) {
-				return t
-			}
-		}
-	}
-
-	// Not in cache, lock and retry.
-	structLookupCache.Lock()
-	defer structLookupCache.Unlock()
-	if ts, ok := structLookupCache.m.Load(hash); ok {
-		for _, st := range ts.([]Type) {
-			t := st.common()
-			if haveIdenticalUnderlyingType(&typ.rtype, t, true) {
-				return t
-			}
-		}
-	}
-
-	addToCache := func(t Type) Type {
-		var ts []Type
-		if ti, ok := structLookupCache.m.Load(hash); ok {
-			ts = ti.([]Type)
-		}
-		structLookupCache.m.Store(hash, append(ts, t))
-		return t
-	}
-
-	// Look in known types.
-	for _, t := range typesByString(str) {
-		if haveIdenticalUnderlyingType(&typ.rtype, t, true) {
-			// even if 't' wasn't a structType with methods, we should be ok
-			// as the 'u uncommonType' field won't be accessed except when
-			// tflag&tflagUncommon is set.
-			return addToCache(t)
-		}
-	}
-
-	typ.str = resolveReflectName(newName(str, "", false))
-	typ.tflag = 0 // TODO: set tflagRegularMemory
-	typ.hash = hash
-	typ.size = size
-	typ.ptrdata = typeptrdata(typ.common())
-	typ.align = typalign
-	typ.fieldAlign = typalign
-	typ.ptrToThis = 0
-	if len(methods) > 0 {
-		typ.tflag |= tflagUncommon
-	}
-
-	if hasGCProg {
-		lastPtrField := 0
-		for i, ft := range fs {
-			if ft.typ.pointers() {
-				lastPtrField = i
-			}
-		}
-		prog := []byte{0, 0, 0, 0} // will be length of prog
-		var off uintptr
-		for i, ft := range fs {
-			if i > lastPtrField {
-				// gcprog should not include anything for any field after
-				// the last field that contains pointer data
-				break
-			}
-			if !ft.typ.pointers() {
-				// Ignore pointerless fields.
-				continue
-			}
-			// Pad to start of this field with zeros.
-			if ft.offset() > off {
-				n := (ft.offset() - off) / goarch.PtrSize
-				prog = append(prog, 0x01, 0x00) // emit a 0 bit
-				if n > 1 {
-					prog = append(prog, 0x81)      // repeat previous bit
-					prog = appendVarint(prog, n-1) // n-1 times
-				}
-				off = ft.offset()
-			}
-
-			prog = appendGCProg(prog, ft.typ)
-			off += ft.typ.ptrdata
-		}
-		prog = append(prog, 0)
-		*(*uint32)(unsafe.Pointer(&prog[0])) = uint32(len(prog) - 4)
-		typ.kind |= kindGCProg
-		typ.gcdata = &prog[0]
-	} else {
-		typ.kind &^= kindGCProg
-		bv := new(bitVector)
-		addTypeBits(bv, 0, typ.common())
-		if len(bv.data) > 0 {
-			typ.gcdata = &bv.data[0]
-		}
-	}
-	typ.equal = nil
-	if comparable {
-		typ.equal = func(p, q unsafe.Pointer) bool {
-			for _, ft := range typ.fields {
-				pi := add(p, ft.offset(), "&x.field safe")
-				qi := add(q, ft.offset(), "&x.field safe")
-				if !ft.typ.equal(pi, qi) {
-					return false
-				}
-			}
-			return true
-		}
-	}
-
-	switch {
-	case len(fs) == 1 && !ifaceIndir(fs[0].typ):
-		// structs of 1 direct iface type can be direct
-		typ.kind |= kindDirectIface
-	default:
-		typ.kind &^= kindDirectIface
-	}
-
-	return addToCache(&typ.rtype)
-}
-
-// runtimeStructField takes a StructField value passed to StructOf and
-// returns both the corresponding internal representation, of type
-// structField, and the pkgpath value to use for this field.
-func runtimeStructField(field StructField) (structField, string) {
-	if field.Anonymous && field.PkgPath != "" {
-		panic("reflect.StructOf: field \"" + field.Name + "\" is anonymous but has PkgPath set")
-	}
-
-	if field.IsExported() {
-		// Best-effort check for misuse.
-		// Since this field will be treated as exported, not much harm done if Unicode lowercase slips through.
-		c := field.Name[0]
-		if 'a' <= c && c <= 'z' || c == '_' {
-			panic("reflect.StructOf: field \"" + field.Name + "\" is unexported but missing PkgPath")
-		}
-	}
-
-	offsetEmbed := uintptr(0)
-	if field.Anonymous {
-		offsetEmbed |= 1
-	}
-
-	resolveReflectType(field.Type.common()) // install in runtime
-	f := structField{
-		name:        newName(field.Name, string(field.Tag), field.IsExported()),
-		typ:         field.Type.common(),
-		offsetEmbed: offsetEmbed,
-	}
-	return f, field.PkgPath
-}
-
-// typeptrdata returns the length in bytes of the prefix of t
-// containing pointer data. Anything after this offset is scalar data.
-// keep in sync with ../cmd/compile/internal/reflectdata/reflect.go
-func typeptrdata(t *rtype) uintptr {
-	switch t.Kind() {
-	case Struct:
-		st := (*structType)(unsafe.Pointer(t))
-		// find the last field that has pointers.
-		field := -1
-		for i := range st.fields {
-			ft := st.fields[i].typ
-			if ft.pointers() {
-				field = i
-			}
-		}
-		if field == -1 {
-			return 0
-		}
-		f := st.fields[field]
-		return f.offset() + f.typ.ptrdata
-
-	default:
-		panic("reflect.typeptrdata: unexpected type, " + t.String())
-	}
-}
-
-// See cmd/compile/internal/reflectdata/reflect.go for derivation of constant.
-const maxPtrmaskBytes = 2048
-
-// ArrayOf returns the array type with the given length and element type.
-// For example, if t represents int, ArrayOf(5, t) represents [5]int.
-//
-// If the resulting type would be larger than the available address space,
-// ArrayOf panics.
-func ArrayOf(length int, elem Type) Type {
-	if length < 0 {
-		panic("reflect: negative length passed to ArrayOf")
-	}
-
-	typ := elem.(*rtype)
-
-	// Look in cache.
-	ckey := cacheKey{Array, typ, nil, uintptr(length)}
-	if array, ok := lookupCache.Load(ckey); ok {
-		return array.(Type)
-	}
-
-	// Look in known types.
-	s := "[" + strconv.Itoa(length) + "]" + typ.String()
-	for _, tt := range typesByString(s) {
-		array := (*arrayType)(unsafe.Pointer(tt))
-		if array.elem == typ {
-			ti, _ := lookupCache.LoadOrStore(ckey, tt)
-			return ti.(Type)
-		}
-	}
-
-	// Make an array type.
-	var iarray any = [1]unsafe.Pointer{}
-	prototype := *(**arrayType)(unsafe.Pointer(&iarray))
-	array := *prototype
-	array.tflag = typ.tflag & tflagRegularMemory
-	array.str = resolveReflectName(newName(s, "", false))
-	array.hash = fnv1(typ.hash, '[')
-	for n := uint32(length); n > 0; n >>= 8 {
-		array.hash = fnv1(array.hash, byte(n))
-	}
-	array.hash = fnv1(array.hash, ']')
-	array.elem = typ
-	array.ptrToThis = 0
-	if typ.size > 0 {
-		max := ^uintptr(0) / typ.size
-		if uintptr(length) > max {
-			panic("reflect.ArrayOf: array size would exceed virtual address space")
-		}
-	}
-	array.size = typ.size * uintptr(length)
-	if length > 0 && typ.ptrdata != 0 {
-		array.ptrdata = typ.size*uintptr(length-1) + typ.ptrdata
-	}
-	array.align = typ.align
-	array.fieldAlign = typ.fieldAlign
-	array.len = uintptr(length)
-	array.slice = SliceOf(elem).(*rtype)
-
-	switch {
-	case typ.ptrdata == 0 || array.size == 0:
-		// No pointers.
-		array.gcdata = nil
-		array.ptrdata = 0
-
-	case length == 1:
-		// In memory, 1-element array looks just like the element.
-		array.kind |= typ.kind & kindGCProg
-		array.gcdata = typ.gcdata
-		array.ptrdata = typ.ptrdata
-
-	case typ.kind&kindGCProg == 0 && array.size <= maxPtrmaskBytes*8*goarch.PtrSize:
-		// Element is small with pointer mask; array is still small.
-		// Create direct pointer mask by turning each 1 bit in elem
-		// into length 1 bits in larger mask.
-		mask := make([]byte, (array.ptrdata/goarch.PtrSize+7)/8)
-		emitGCMask(mask, 0, typ, array.len)
-		array.gcdata = &mask[0]
-
-	default:
-		// Create program that emits one element
-		// and then repeats to make the array.
-		prog := []byte{0, 0, 0, 0} // will be length of prog
-		prog = appendGCProg(prog, typ)
-		// Pad from ptrdata to size.
-		elemPtrs := typ.ptrdata / goarch.PtrSize
-		elemWords := typ.size / goarch.PtrSize
-		if elemPtrs < elemWords {
-			// Emit literal 0 bit, then repeat as needed.
-			prog = append(prog, 0x01, 0x00)
-			if elemPtrs+1 < elemWords {
-				prog = append(prog, 0x81)
-				prog = appendVarint(prog, elemWords-elemPtrs-1)
-			}
-		}
-		// Repeat length-1 times.
-		if elemWords < 0x80 {
-			prog = append(prog, byte(elemWords|0x80))
-		} else {
-			prog = append(prog, 0x80)
-			prog = appendVarint(prog, elemWords)
-		}
-		prog = appendVarint(prog, uintptr(length)-1)
-		prog = append(prog, 0)
-		*(*uint32)(unsafe.Pointer(&prog[0])) = uint32(len(prog) - 4)
-		array.kind |= kindGCProg
-		array.gcdata = &prog[0]
-		array.ptrdata = array.size // overestimate but ok; must match program
-	}
-
-	etyp := typ.common()
-	esize := etyp.Size()
-
-	array.equal = nil
-	if eequal := etyp.equal; eequal != nil {
-		array.equal = func(p, q unsafe.Pointer) bool {
-			for i := 0; i < length; i++ {
-				pi := arrayAt(p, i, esize, "i < length")
-				qi := arrayAt(q, i, esize, "i < length")
-				if !eequal(pi, qi) {
-					return false
-				}
-
-			}
-			return true
-		}
-	}
-
-	switch {
-	case length == 1 && !ifaceIndir(typ):
-		// array of 1 direct iface type can be direct
-		array.kind |= kindDirectIface
-	default:
-		array.kind &^= kindDirectIface
-	}
-
-	ti, _ := lookupCache.LoadOrStore(ckey, &array.rtype)
-	return ti.(Type)
-}
-
-func appendVarint(x []byte, v uintptr) []byte {
-	for ; v >= 0x80; v >>= 7 {
-		x = append(x, byte(v|0x80))
-	}
-	x = append(x, byte(v))
-	return x
-}
-
-// toType converts from a *rtype to a Type that can be returned
-// to the client of package reflect. In gc, the only concern is that
-// a nil *rtype must be replaced by a nil Type, but in gccgo this
-// function takes care of ensuring that multiple *rtype for the same
-// type are coalesced into a single Type.
-func toType(t *rtype) Type {
-	if t == nil {
-		return nil
-	}
-	return t
-}
-
-type layoutKey struct {
-	ftyp *funcType // function signature
-	rcvr *rtype    // receiver type, or nil if none
-}
-
-type layoutType struct {
-	t         *rtype
-	framePool *sync.Pool
-	abi       abiDesc
-}
-
-var layoutCache sync.Map // map[layoutKey]layoutType
-
-// funcLayout computes a struct type representing the layout of the
-// stack-assigned function arguments and return values for the function
-// type t.
-// If rcvr != nil, rcvr specifies the type of the receiver.
-// The returned type exists only for GC, so we only fill out GC relevant info.
-// Currently, that's just size and the GC program. We also fill in
-// the name for possible debugging use.
-func funcLayout(t *funcType, rcvr *rtype) (frametype *rtype, framePool *sync.Pool, abi abiDesc) {
-	if t.Kind() != Func {
-		panic("reflect: funcLayout of non-func type " + t.String())
-	}
-	if rcvr != nil && rcvr.Kind() == Interface {
-		panic("reflect: funcLayout with interface receiver " + rcvr.String())
-	}
-	k := layoutKey{t, rcvr}
-	if lti, ok := layoutCache.Load(k); ok {
-		lt := lti.(layoutType)
-		return lt.t, lt.framePool, lt.abi
-	}
-
-	// Compute the ABI layout.
-	abi = newAbiDesc(t, rcvr)
-
-	// build dummy rtype holding gc program
-	x := &rtype{
-		align: goarch.PtrSize,
-		// Don't add spill space here; it's only necessary in
-		// reflectcall's frame, not in the allocated frame.
-		// TODO(mknyszek): Remove this comment when register
-		// spill space in the frame is no longer required.
-		size:    align(abi.retOffset+abi.ret.stackBytes, goarch.PtrSize),
-		ptrdata: uintptr(abi.stackPtrs.n) * goarch.PtrSize,
-	}
-	if abi.stackPtrs.n > 0 {
-		x.gcdata = &abi.stackPtrs.data[0]
-	}
-
-	var s string
-	if rcvr != nil {
-		s = "methodargs(" + rcvr.String() + ")(" + t.String() + ")"
-	} else {
-		s = "funcargs(" + t.String() + ")"
-	}
-	x.str = resolveReflectName(newName(s, "", false))
-
-	// cache result for future callers
-	framePool = &sync.Pool{New: func() any {
-		return unsafe_New(x)
-	}}
-	lti, _ := layoutCache.LoadOrStore(k, layoutType{
-		t:         x,
-		framePool: framePool,
-		abi:       abi,
-	})
-	lt := lti.(layoutType)
-	return lt.t, lt.framePool, lt.abi
-}
-
-// ifaceIndir reports whether t is stored indirectly in an interface value.
-func ifaceIndir(t *rtype) bool {
-	return t.kind&kindDirectIface == 0
-}
-
-// Note: this type must agree with runtime.bitvector.
-type bitVector struct {
-	n    uint32 // number of bits
-	data []byte
-}
-
-// append a bit to the bitmap.
-func (bv *bitVector) append(bit uint8) {
-	if bv.n%8 == 0 {
-		bv.data = append(bv.data, 0)
-	}
-	bv.data[bv.n/8] |= bit << (bv.n % 8)
-	bv.n++
-}
-
-func addTypeBits(bv *bitVector, offset uintptr, t *rtype) {
-	if t.ptrdata == 0 {
-		return
-	}
-
-	switch Kind(t.kind & kindMask) {
-	case Chan, Func, Map, Pointer, Slice, String, UnsafePointer:
-		// 1 pointer at start of representation
-		for bv.n < uint32(offset/uintptr(goarch.PtrSize)) {
-			bv.append(0)
-		}
-		bv.append(1)
-
-	case Interface:
-		// 2 pointers
-		for bv.n < uint32(offset/uintptr(goarch.PtrSize)) {
-			bv.append(0)
-		}
-		bv.append(1)
-		bv.append(1)
-
-	case Array:
-		// repeat inner type
-		tt := (*arrayType)(unsafe.Pointer(t))
-		for i := 0; i < int(tt.len); i++ {
-			addTypeBits(bv, offset+uintptr(i)*tt.elem.size, tt.elem)
-		}
-
-	case Struct:
-		// apply fields
-		tt := (*structType)(unsafe.Pointer(t))
-		for i := range tt.fields {
-			f := &tt.fields[i]
-			addTypeBits(bv, offset+f.offset(), f.typ)
-		}
-	}
-}
diff --git a/contrib/go/_std_1.18/src/reflect/value.go b/contrib/go/_std_1.18/src/reflect/value.go
deleted file mode 100644
index 147b402b2a..0000000000
--- a/contrib/go/_std_1.18/src/reflect/value.go
+++ /dev/null
@@ -1,3532 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package reflect
-
-import (
-	"errors"
-	"internal/abi"
-	"internal/goarch"
-	"internal/itoa"
-	"internal/unsafeheader"
-	"math"
-	"runtime"
-	"unsafe"
-)
-
-// Value is the reflection interface to a Go value.
-//
-// Not all methods apply to all kinds of values. Restrictions,
-// if any, are noted in the documentation for each method.
-// Use the Kind method to find out the kind of value before
-// calling kind-specific methods. Calling a method
-// inappropriate to the kind of type causes a run time panic.
-//
-// The zero Value represents no value.
-// Its IsValid method returns false, its Kind method returns Invalid,
-// its String method returns "<invalid Value>", and all other methods panic.
-// Most functions and methods never return an invalid value.
-// If one does, its documentation states the conditions explicitly.
-//
-// A Value can be used concurrently by multiple goroutines provided that
-// the underlying Go value can be used concurrently for the equivalent
-// direct operations.
-//
-// To compare two Values, compare the results of the Interface method.
-// Using == on two Values does not compare the underlying values
-// they represent.
-type Value struct {
-	// typ holds the type of the value represented by a Value.
-	typ *rtype
-
-	// Pointer-valued data or, if flagIndir is set, pointer to data.
-	// Valid when either flagIndir is set or typ.pointers() is true.
-	ptr unsafe.Pointer
-
-	// flag holds metadata about the value.
-	// The lowest bits are flag bits:
-	//	- flagStickyRO: obtained via unexported not embedded field, so read-only
-	//	- flagEmbedRO: obtained via unexported embedded field, so read-only
-	//	- flagIndir: val holds a pointer to the data
-	//	- flagAddr: v.CanAddr is true (implies flagIndir)
-	//	- flagMethod: v is a method value.
-	// The next five bits give the Kind of the value.
-	// This repeats typ.Kind() except for method values.
-	// The remaining 23+ bits give a method number for method values.
-	// If flag.kind() != Func, code can assume that flagMethod is unset.
-	// If ifaceIndir(typ), code can assume that flagIndir is set.
-	flag
-
-	// A method value represents a curried method invocation
-	// like r.Read for some receiver r. The typ+val+flag bits describe
-	// the receiver r, but the flag's Kind bits say Func (methods are
-	// functions), and the top bits of the flag give the method number
-	// in r's type's method table.
-}
-
-type flag uintptr
-
-const (
-	flagKindWidth        = 5 // there are 27 kinds
-	flagKindMask    flag = 1<<flagKindWidth - 1
-	flagStickyRO    flag = 1 << 5
-	flagEmbedRO     flag = 1 << 6
-	flagIndir       flag = 1 << 7
-	flagAddr        flag = 1 << 8
-	flagMethod      flag = 1 << 9
-	flagMethodShift      = 10
-	flagRO          flag = flagStickyRO | flagEmbedRO
-)
-
-func (f flag) kind() Kind {
-	return Kind(f & flagKindMask)
-}
-
-func (f flag) ro() flag {
-	if f&flagRO != 0 {
-		return flagStickyRO
-	}
-	return 0
-}
-
-// pointer returns the underlying pointer represented by v.
-// v.Kind() must be Pointer, Map, Chan, Func, or UnsafePointer
-// if v.Kind() == Pointer, the base type must not be go:notinheap.
-func (v Value) pointer() unsafe.Pointer {
-	if v.typ.size != goarch.PtrSize || !v.typ.pointers() {
-		panic("can't call pointer on a non-pointer Value")
-	}
-	if v.flag&flagIndir != 0 {
-		return *(*unsafe.Pointer)(v.ptr)
-	}
-	return v.ptr
-}
-
-// packEface converts v to the empty interface.
-func packEface(v Value) any {
-	t := v.typ
-	var i any
-	e := (*emptyInterface)(unsafe.Pointer(&i))
-	// First, fill in the data portion of the interface.
-	switch {
-	case ifaceIndir(t):
-		if v.flag&flagIndir == 0 {
-			panic("bad indir")
-		}
-		// Value is indirect, and so is the interface we're making.
-		ptr := v.ptr
-		if v.flag&flagAddr != 0 {
-			// TODO: pass safe boolean from valueInterface so
-			// we don't need to copy if safe==true?
-			c := unsafe_New(t)
-			typedmemmove(t, c, ptr)
-			ptr = c
-		}
-		e.word = ptr
-	case v.flag&flagIndir != 0:
-		// Value is indirect, but interface is direct. We need
-		// to load the data at v.ptr into the interface data word.
-		e.word = *(*unsafe.Pointer)(v.ptr)
-	default:
-		// Value is direct, and so is the interface.
-		e.word = v.ptr
-	}
-	// Now, fill in the type portion. We're very careful here not
-	// to have any operation between the e.word and e.typ assignments
-	// that would let the garbage collector observe the partially-built
-	// interface value.
-	e.typ = t
-	return i
-}
-
-// unpackEface converts the empty interface i to a Value.
-func unpackEface(i any) Value {
-	e := (*emptyInterface)(unsafe.Pointer(&i))
-	// NOTE: don't read e.word until we know whether it is really a pointer or not.
-	t := e.typ
-	if t == nil {
-		return Value{}
-	}
-	f := flag(t.Kind())
-	if ifaceIndir(t) {
-		f |= flagIndir
-	}
-	return Value{t, e.word, f}
-}
-
-// A ValueError occurs when a Value method is invoked on
-// a Value that does not support it. Such cases are documented
-// in the description of each method.
-type ValueError struct {
-	Method string
-	Kind   Kind
-}
-
-func (e *ValueError) Error() string {
-	if e.Kind == 0 {
-		return "reflect: call of " + e.Method + " on zero Value"
-	}
-	return "reflect: call of " + e.Method + " on " + e.Kind.String() + " Value"
-}
-
-// methodName returns the name of the calling method,
-// assumed to be two stack frames above.
-func methodName() string {
-	pc, _, _, _ := runtime.Caller(2)
-	f := runtime.FuncForPC(pc)
-	if f == nil {
-		return "unknown method"
-	}
-	return f.Name()
-}
-
-// methodNameSkip is like methodName, but skips another stack frame.
-// This is a separate function so that reflect.flag.mustBe will be inlined.
-func methodNameSkip() string {
-	pc, _, _, _ := runtime.Caller(3)
-	f := runtime.FuncForPC(pc)
-	if f == nil {
-		return "unknown method"
-	}
-	return f.Name()
-}
-
-// emptyInterface is the header for an interface{} value.
-type emptyInterface struct {
-	typ  *rtype
-	word unsafe.Pointer
-}
-
-// nonEmptyInterface is the header for an interface value with methods.
-type nonEmptyInterface struct {
-	// see ../runtime/iface.go:/Itab
-	itab *struct {
-		ityp *rtype // static interface type
-		typ  *rtype // dynamic concrete type
-		hash uint32 // copy of typ.hash
-		_    [4]byte
-		fun  [100000]unsafe.Pointer // method table
-	}
-	word unsafe.Pointer
-}
-
-// mustBe panics if f's kind is not expected.
-// Making this a method on flag instead of on Value
-// (and embedding flag in Value) means that we can write
-// the very clear v.mustBe(Bool) and have it compile into
-// v.flag.mustBe(Bool), which will only bother to copy the
-// single important word for the receiver.
-func (f flag) mustBe(expected Kind) {
-	// TODO(mvdan): use f.kind() again once mid-stack inlining gets better
-	if Kind(f&flagKindMask) != expected {
-		panic(&ValueError{methodName(), f.kind()})
-	}
-}
-
-// mustBeExported panics if f records that the value was obtained using
-// an unexported field.
-func (f flag) mustBeExported() {
-	if f == 0 || f&flagRO != 0 {
-		f.mustBeExportedSlow()
-	}
-}
-
-func (f flag) mustBeExportedSlow() {
-	if f == 0 {
-		panic(&ValueError{methodNameSkip(), Invalid})
-	}
-	if f&flagRO != 0 {
-		panic("reflect: " + methodNameSkip() + " using value obtained using unexported field")
-	}
-}
-
-// mustBeAssignable panics if f records that the value is not assignable,
-// which is to say that either it was obtained using an unexported field
-// or it is not addressable.
-func (f flag) mustBeAssignable() {
-	if f&flagRO != 0 || f&flagAddr == 0 {
-		f.mustBeAssignableSlow()
-	}
-}
-
-func (f flag) mustBeAssignableSlow() {
-	if f == 0 {
-		panic(&ValueError{methodNameSkip(), Invalid})
-	}
-	// Assignable if addressable and not read-only.
-	if f&flagRO != 0 {
-		panic("reflect: " + methodNameSkip() + " using value obtained using unexported field")
-	}
-	if f&flagAddr == 0 {
-		panic("reflect: " + methodNameSkip() + " using unaddressable value")
-	}
-}
-
-// Addr returns a pointer value representing the address of v.
-// It panics if CanAddr() returns false.
-// Addr is typically used to obtain a pointer to a struct field
-// or slice element in order to call a method that requires a
-// pointer receiver.
-func (v Value) Addr() Value {
-	if v.flag&flagAddr == 0 {
-		panic("reflect.Value.Addr of unaddressable value")
-	}
-	// Preserve flagRO instead of using v.flag.ro() so that
-	// v.Addr().Elem() is equivalent to v (#32772)
-	fl := v.flag & flagRO
-	return Value{v.typ.ptrTo(), v.ptr, fl | flag(Pointer)}
-}
-
-// Bool returns v's underlying value.
-// It panics if v's kind is not Bool.
-func (v Value) Bool() bool {
-	v.mustBe(Bool)
-	return *(*bool)(v.ptr)
-}
-
-// Bytes returns v's underlying value.
-// It panics if v's underlying value is not a slice of bytes.
-func (v Value) Bytes() []byte {
-	v.mustBe(Slice)
-	if v.typ.Elem().Kind() != Uint8 {
-		panic("reflect.Value.Bytes of non-byte slice")
-	}
-	// Slice is always bigger than a word; assume flagIndir.
-	return *(*[]byte)(v.ptr)
-}
-
-// runes returns v's underlying value.
-// It panics if v's underlying value is not a slice of runes (int32s).
-func (v Value) runes() []rune {
-	v.mustBe(Slice)
-	if v.typ.Elem().Kind() != Int32 {
-		panic("reflect.Value.Bytes of non-rune slice")
-	}
-	// Slice is always bigger than a word; assume flagIndir.
-	return *(*[]rune)(v.ptr)
-}
-
-// CanAddr reports whether the value's address can be obtained with Addr.
-// Such values are called addressable. A value is addressable if it is
-// an element of a slice, an element of an addressable array,
-// a field of an addressable struct, or the result of dereferencing a pointer.
-// If CanAddr returns false, calling Addr will panic.
-func (v Value) CanAddr() bool {
-	return v.flag&flagAddr != 0
-}
-
-// CanSet reports whether the value of v can be changed.
-// A Value can be changed only if it is addressable and was not
-// obtained by the use of unexported struct fields.
-// If CanSet returns false, calling Set or any type-specific
-// setter (e.g., SetBool, SetInt) will panic.
-func (v Value) CanSet() bool {
-	return v.flag&(flagAddr|flagRO) == flagAddr
-}
-
-// Call calls the function v with the input arguments in.
-// For example, if len(in) == 3, v.Call(in) represents the Go call v(in[0], in[1], in[2]).
-// Call panics if v's Kind is not Func.
-// It returns the output results as Values.
-// As in Go, each input argument must be assignable to the
-// type of the function's corresponding input parameter.
-// If v is a variadic function, Call creates the variadic slice parameter
-// itself, copying in the corresponding values.
-func (v Value) Call(in []Value) []Value {
-	v.mustBe(Func)
-	v.mustBeExported()
-	return v.call("Call", in)
-}
-
-// CallSlice calls the variadic function v with the input arguments in,
-// assigning the slice in[len(in)-1] to v's final variadic argument.
-// For example, if len(in) == 3, v.CallSlice(in) represents the Go call v(in[0], in[1], in[2]...).
-// CallSlice panics if v's Kind is not Func or if v is not variadic.
-// It returns the output results as Values.
-// As in Go, each input argument must be assignable to the
-// type of the function's corresponding input parameter.
-func (v Value) CallSlice(in []Value) []Value {
-	v.mustBe(Func)
-	v.mustBeExported()
-	return v.call("CallSlice", in)
-}
-
-var callGC bool // for testing; see TestCallMethodJump and TestCallArgLive
-
-const debugReflectCall = false
-
-func (v Value) call(op string, in []Value) []Value {
-	// Get function pointer, type.
-	t := (*funcType)(unsafe.Pointer(v.typ))
-	var (
-		fn       unsafe.Pointer
-		rcvr     Value
-		rcvrtype *rtype
-	)
-	if v.flag&flagMethod != 0 {
-		rcvr = v
-		rcvrtype, t, fn = methodReceiver(op, v, int(v.flag)>>flagMethodShift)
-	} else if v.flag&flagIndir != 0 {
-		fn = *(*unsafe.Pointer)(v.ptr)
-	} else {
-		fn = v.ptr
-	}
-
-	if fn == nil {
-		panic("reflect.Value.Call: call of nil function")
-	}
-
-	isSlice := op == "CallSlice"
-	n := t.NumIn()
-	isVariadic := t.IsVariadic()
-	if isSlice {
-		if !isVariadic {
-			panic("reflect: CallSlice of non-variadic function")
-		}
-		if len(in) < n {
-			panic("reflect: CallSlice with too few input arguments")
-		}
-		if len(in) > n {
-			panic("reflect: CallSlice with too many input arguments")
-		}
-	} else {
-		if isVariadic {
-			n--
-		}
-		if len(in) < n {
-			panic("reflect: Call with too few input arguments")
-		}
-		if !isVariadic && len(in) > n {
-			panic("reflect: Call with too many input arguments")
-		}
-	}
-	for _, x := range in {
-		if x.Kind() == Invalid {
-			panic("reflect: " + op + " using zero Value argument")
-		}
-	}
-	for i := 0; i < n; i++ {
-		if xt, targ := in[i].Type(), t.In(i); !xt.AssignableTo(targ) {
-			panic("reflect: " + op + " using " + xt.String() + " as type " + targ.String())
-		}
-	}
-	if !isSlice && isVariadic {
-		// prepare slice for remaining values
-		m := len(in) - n
-		slice := MakeSlice(t.In(n), m, m)
-		elem := t.In(n).Elem()
-		for i := 0; i < m; i++ {
-			x := in[n+i]
-			if xt := x.Type(); !xt.AssignableTo(elem) {
-				panic("reflect: cannot use " + xt.String() + " as type " + elem.String() + " in " + op)
-			}
-			slice.Index(i).Set(x)
-		}
-		origIn := in
-		in = make([]Value, n+1)
-		copy(in[:n], origIn)
-		in[n] = slice
-	}
-
-	nin := len(in)
-	if nin != t.NumIn() {
-		panic("reflect.Value.Call: wrong argument count")
-	}
-	nout := t.NumOut()
-
-	// Register argument space.
-	var regArgs abi.RegArgs
-
-	// Compute frame type.
-	frametype, framePool, abi := funcLayout(t, rcvrtype)
-
-	// Allocate a chunk of memory for frame if needed.
-	var stackArgs unsafe.Pointer
-	if frametype.size != 0 {
-		if nout == 0 {
-			stackArgs = framePool.Get().(unsafe.Pointer)
-		} else {
-			// Can't use pool if the function has return values.
-			// We will leak pointer to args in ret, so its lifetime is not scoped.
-			stackArgs = unsafe_New(frametype)
-		}
-	}
-	frameSize := frametype.size
-
-	if debugReflectCall {
-		println("reflect.call", t.String())
-		abi.dump()
-	}
-
-	// Copy inputs into args.
-
-	// Handle receiver.
-	inStart := 0
-	if rcvrtype != nil {
-		// Guaranteed to only be one word in size,
-		// so it will only take up exactly 1 abiStep (either
-		// in a register or on the stack).
-		switch st := abi.call.steps[0]; st.kind {
-		case abiStepStack:
-			storeRcvr(rcvr, stackArgs)
-		case abiStepIntReg, abiStepPointer:
-			// Even pointers can go into the uintptr slot because
-			// they'll be kept alive by the Values referenced by
-			// this frame. Reflection forces these to be heap-allocated,
-			// so we don't need to worry about stack copying.
-			storeRcvr(rcvr, unsafe.Pointer(&regArgs.Ints[st.ireg]))
-		case abiStepFloatReg:
-			storeRcvr(rcvr, unsafe.Pointer(&regArgs.Floats[st.freg]))
-		default:
-			panic("unknown ABI parameter kind")
-		}
-		inStart = 1
-	}
-
-	// Handle arguments.
-	for i, v := range in {
-		v.mustBeExported()
-		targ := t.In(i).(*rtype)
-		// TODO(mknyszek): Figure out if it's possible to get some
-		// scratch space for this assignment check. Previously, it
-		// was possible to use space in the argument frame.
-		v = v.assignTo("reflect.Value.Call", targ, nil)
-	stepsLoop:
-		for _, st := range abi.call.stepsForValue(i + inStart) {
-			switch st.kind {
-			case abiStepStack:
-				// Copy values to the "stack."
-				addr := add(stackArgs, st.stkOff, "precomputed stack arg offset")
-				if v.flag&flagIndir != 0 {
-					typedmemmove(targ, addr, v.ptr)
-				} else {
-					*(*unsafe.Pointer)(addr) = v.ptr
-				}
-				// There's only one step for a stack-allocated value.
-				break stepsLoop
-			case abiStepIntReg, abiStepPointer:
-				// Copy values to "integer registers."
-				if v.flag&flagIndir != 0 {
-					offset := add(v.ptr, st.offset, "precomputed value offset")
-					if st.kind == abiStepPointer {
-						// Duplicate this pointer in the pointer area of the
-						// register space. Otherwise, there's the potential for
-						// this to be the last reference to v.ptr.
-						regArgs.Ptrs[st.ireg] = *(*unsafe.Pointer)(offset)
-					}
-					intToReg(&regArgs, st.ireg, st.size, offset)
-				} else {
-					if st.kind == abiStepPointer {
-						// See the comment in abiStepPointer case above.
-						regArgs.Ptrs[st.ireg] = v.ptr
-					}
-					regArgs.Ints[st.ireg] = uintptr(v.ptr)
-				}
-			case abiStepFloatReg:
-				// Copy values to "float registers."
-				if v.flag&flagIndir == 0 {
-					panic("attempted to copy pointer to FP register")
-				}
-				offset := add(v.ptr, st.offset, "precomputed value offset")
-				floatToReg(&regArgs, st.freg, st.size, offset)
-			default:
-				panic("unknown ABI part kind")
-			}
-		}
-	}
-	// TODO(mknyszek): Remove this when we no longer have
-	// caller reserved spill space.
-	frameSize = align(frameSize, goarch.PtrSize)
-	frameSize += abi.spill
-
-	// Mark pointers in registers for the return path.
-	regArgs.ReturnIsPtr = abi.outRegPtrs
-
-	if debugReflectCall {
-		regArgs.Dump()
-	}
-
-	// For testing; see TestCallArgLive.
-	if callGC {
-		runtime.GC()
-	}
-
-	// Call.
-	call(frametype, fn, stackArgs, uint32(frametype.size), uint32(abi.retOffset), uint32(frameSize), &regArgs)
-
-	// For testing; see TestCallMethodJump.
-	if callGC {
-		runtime.GC()
-	}
-
-	var ret []Value
-	if nout == 0 {
-		if stackArgs != nil {
-			typedmemclr(frametype, stackArgs)
-			framePool.Put(stackArgs)
-		}
-	} else {
-		if stackArgs != nil {
-			// Zero the now unused input area of args,
-			// because the Values returned by this function contain pointers to the args object,
-			// and will thus keep the args object alive indefinitely.
-			typedmemclrpartial(frametype, stackArgs, 0, abi.retOffset)
-		}
-
-		// Wrap Values around return values in args.
-		ret = make([]Value, nout)
-		for i := 0; i < nout; i++ {
-			tv := t.Out(i)
-			if tv.Size() == 0 {
-				// For zero-sized return value, args+off may point to the next object.
-				// In this case, return the zero value instead.
-				ret[i] = Zero(tv)
-				continue
-			}
-			steps := abi.ret.stepsForValue(i)
-			if st := steps[0]; st.kind == abiStepStack {
-				// This value is on the stack. If part of a value is stack
-				// allocated, the entire value is according to the ABI. So
-				// just make an indirection into the allocated frame.
-				fl := flagIndir | flag(tv.Kind())
-				ret[i] = Value{tv.common(), add(stackArgs, st.stkOff, "tv.Size() != 0"), fl}
-				// Note: this does introduce false sharing between results -
-				// if any result is live, they are all live.
-				// (And the space for the args is live as well, but as we've
-				// cleared that space it isn't as big a deal.)
-				continue
-			}
-
-			// Handle pointers passed in registers.
-			if !ifaceIndir(tv.common()) {
-				// Pointer-valued data gets put directly
-				// into v.ptr.
-				if steps[0].kind != abiStepPointer {
-					print("kind=", steps[0].kind, ", type=", tv.String(), "\n")
-					panic("mismatch between ABI description and types")
-				}
-				ret[i] = Value{tv.common(), regArgs.Ptrs[steps[0].ireg], flag(tv.Kind())}
-				continue
-			}
-
-			// All that's left is values passed in registers that we need to
-			// create space for and copy values back into.
-			//
-			// TODO(mknyszek): We make a new allocation for each register-allocated
-			// value, but previously we could always point into the heap-allocated
-			// stack frame. This is a regression that could be fixed by adding
-			// additional space to the allocated stack frame and storing the
-			// register-allocated return values into the allocated stack frame and
-			// referring there in the resulting Value.
-			s := unsafe_New(tv.common())
-			for _, st := range steps {
-				switch st.kind {
-				case abiStepIntReg:
-					offset := add(s, st.offset, "precomputed value offset")
-					intFromReg(&regArgs, st.ireg, st.size, offset)
-				case abiStepPointer:
-					s := add(s, st.offset, "precomputed value offset")
-					*((*unsafe.Pointer)(s)) = regArgs.Ptrs[st.ireg]
-				case abiStepFloatReg:
-					offset := add(s, st.offset, "precomputed value offset")
-					floatFromReg(&regArgs, st.freg, st.size, offset)
-				case abiStepStack:
-					panic("register-based return value has stack component")
-				default:
-					panic("unknown ABI part kind")
-				}
-			}
-			ret[i] = Value{tv.common(), s, flagIndir | flag(tv.Kind())}
-		}
-	}
-
-	return ret
-}
-
-// callReflect is the call implementation used by a function
-// returned by MakeFunc. In many ways it is the opposite of the
-// method Value.call above. The method above converts a call using Values
-// into a call of a function with a concrete argument frame, while
-// callReflect converts a call of a function with a concrete argument
-// frame into a call using Values.
-// It is in this file so that it can be next to the call method above.
-// The remainder of the MakeFunc implementation is in makefunc.go.
-//
-// NOTE: This function must be marked as a "wrapper" in the generated code,
-// so that the linker can make it work correctly for panic and recover.
-// The gc compilers know to do that for the name "reflect.callReflect".
-//
-// ctxt is the "closure" generated by MakeFunc.
-// frame is a pointer to the arguments to that closure on the stack.
-// retValid points to a boolean which should be set when the results
-// section of frame is set.
-//
-// regs contains the argument values passed in registers and will contain
-// the values returned from ctxt.fn in registers.
-func callReflect(ctxt *makeFuncImpl, frame unsafe.Pointer, retValid *bool, regs *abi.RegArgs) {
-	if callGC {
-		// Call GC upon entry during testing.
-		// Getting our stack scanned here is the biggest hazard, because
-		// our caller (makeFuncStub) could have failed to place the last
-		// pointer to a value in regs' pointer space, in which case it
-		// won't be visible to the GC.
-		runtime.GC()
-	}
-	ftyp := ctxt.ftyp
-	f := ctxt.fn
-
-	_, _, abi := funcLayout(ftyp, nil)
-
-	// Copy arguments into Values.
-	ptr := frame
-	in := make([]Value, 0, int(ftyp.inCount))
-	for i, typ := range ftyp.in() {
-		if typ.Size() == 0 {
-			in = append(in, Zero(typ))
-			continue
-		}
-		v := Value{typ, nil, flag(typ.Kind())}
-		steps := abi.call.stepsForValue(i)
-		if st := steps[0]; st.kind == abiStepStack {
-			if ifaceIndir(typ) {
-				// value cannot be inlined in interface data.
-				// Must make a copy, because f might keep a reference to it,
-				// and we cannot let f keep a reference to the stack frame
-				// after this function returns, not even a read-only reference.
-				v.ptr = unsafe_New(typ)
-				if typ.size > 0 {
-					typedmemmove(typ, v.ptr, add(ptr, st.stkOff, "typ.size > 0"))
-				}
-				v.flag |= flagIndir
-			} else {
-				v.ptr = *(*unsafe.Pointer)(add(ptr, st.stkOff, "1-ptr"))
-			}
-		} else {
-			if ifaceIndir(typ) {
-				// All that's left is values passed in registers that we need to
-				// create space for the values.
-				v.flag |= flagIndir
-				v.ptr = unsafe_New(typ)
-				for _, st := range steps {
-					switch st.kind {
-					case abiStepIntReg:
-						offset := add(v.ptr, st.offset, "precomputed value offset")
-						intFromReg(regs, st.ireg, st.size, offset)
-					case abiStepPointer:
-						s := add(v.ptr, st.offset, "precomputed value offset")
-						*((*unsafe.Pointer)(s)) = regs.Ptrs[st.ireg]
-					case abiStepFloatReg:
-						offset := add(v.ptr, st.offset, "precomputed value offset")
-						floatFromReg(regs, st.freg, st.size, offset)
-					case abiStepStack:
-						panic("register-based return value has stack component")
-					default:
-						panic("unknown ABI part kind")
-					}
-				}
-			} else {
-				// Pointer-valued data gets put directly
-				// into v.ptr.
-				if steps[0].kind != abiStepPointer {
-					print("kind=", steps[0].kind, ", type=", typ.String(), "\n")
-					panic("mismatch between ABI description and types")
-				}
-				v.ptr = regs.Ptrs[steps[0].ireg]
-			}
-		}
-		in = append(in, v)
-	}
-
-	// Call underlying function.
-	out := f(in)
-	numOut := ftyp.NumOut()
-	if len(out) != numOut {
-		panic("reflect: wrong return count from function created by MakeFunc")
-	}
-
-	// Copy results back into argument frame and register space.
-	if numOut > 0 {
-		for i, typ := range ftyp.out() {
-			v := out[i]
-			if v.typ == nil {
-				panic("reflect: function created by MakeFunc using " + funcName(f) +
-					" returned zero Value")
-			}
-			if v.flag&flagRO != 0 {
-				panic("reflect: function created by MakeFunc using " + funcName(f) +
-					" returned value obtained from unexported field")
-			}
-			if typ.size == 0 {
-				continue
-			}
-
-			// Convert v to type typ if v is assignable to a variable
-			// of type t in the language spec.
-			// See issue 28761.
-			//
-			//
-			// TODO(mknyszek): In the switch to the register ABI we lost
-			// the scratch space here for the register cases (and
-			// temporarily for all the cases).
-			//
-			// If/when this happens, take note of the following:
-			//
-			// We must clear the destination before calling assignTo,
-			// in case assignTo writes (with memory barriers) to the
-			// target location used as scratch space. See issue 39541.
-			v = v.assignTo("reflect.MakeFunc", typ, nil)
-		stepsLoop:
-			for _, st := range abi.ret.stepsForValue(i) {
-				switch st.kind {
-				case abiStepStack:
-					// Copy values to the "stack."
-					addr := add(ptr, st.stkOff, "precomputed stack arg offset")
-					// Do not use write barriers. The stack space used
-					// for this call is not adequately zeroed, and we
-					// are careful to keep the arguments alive until we
-					// return to makeFuncStub's caller.
-					if v.flag&flagIndir != 0 {
-						memmove(addr, v.ptr, st.size)
-					} else {
-						// This case must be a pointer type.
-						*(*uintptr)(addr) = uintptr(v.ptr)
-					}
-					// There's only one step for a stack-allocated value.
-					break stepsLoop
-				case abiStepIntReg, abiStepPointer:
-					// Copy values to "integer registers."
-					if v.flag&flagIndir != 0 {
-						offset := add(v.ptr, st.offset, "precomputed value offset")
-						intToReg(regs, st.ireg, st.size, offset)
-					} else {
-						// Only populate the Ints space on the return path.
-						// This is safe because out is kept alive until the
-						// end of this function, and the return path through
-						// makeFuncStub has no preemption, so these pointers
-						// are always visible to the GC.
-						regs.Ints[st.ireg] = uintptr(v.ptr)
-					}
-				case abiStepFloatReg:
-					// Copy values to "float registers."
-					if v.flag&flagIndir == 0 {
-						panic("attempted to copy pointer to FP register")
-					}
-					offset := add(v.ptr, st.offset, "precomputed value offset")
-					floatToReg(regs, st.freg, st.size, offset)
-				default:
-					panic("unknown ABI part kind")
-				}
-			}
-		}
-	}
-
-	// Announce that the return values are valid.
-	// After this point the runtime can depend on the return values being valid.
-	*retValid = true
-
-	// We have to make sure that the out slice lives at least until
-	// the runtime knows the return values are valid. Otherwise, the
-	// return values might not be scanned by anyone during a GC.
-	// (out would be dead, and the return slots not yet alive.)
-	runtime.KeepAlive(out)
-
-	// runtime.getArgInfo expects to be able to find ctxt on the
-	// stack when it finds our caller, makeFuncStub. Make sure it
-	// doesn't get garbage collected.
-	runtime.KeepAlive(ctxt)
-}
-
-// methodReceiver returns information about the receiver
-// described by v. The Value v may or may not have the
-// flagMethod bit set, so the kind cached in v.flag should
-// not be used.
-// The return value rcvrtype gives the method's actual receiver type.
-// The return value t gives the method type signature (without the receiver).
-// The return value fn is a pointer to the method code.
-func methodReceiver(op string, v Value, methodIndex int) (rcvrtype *rtype, t *funcType, fn unsafe.Pointer) {
-	i := methodIndex
-	if v.typ.Kind() == Interface {
-		tt := (*interfaceType)(unsafe.Pointer(v.typ))
-		if uint(i) >= uint(len(tt.methods)) {
-			panic("reflect: internal error: invalid method index")
-		}
-		m := &tt.methods[i]
-		if !tt.nameOff(m.name).isExported() {
-			panic("reflect: " + op + " of unexported method")
-		}
-		iface := (*nonEmptyInterface)(v.ptr)
-		if iface.itab == nil {
-			panic("reflect: " + op + " of method on nil interface value")
-		}
-		rcvrtype = iface.itab.typ
-		fn = unsafe.Pointer(&iface.itab.fun[i])
-		t = (*funcType)(unsafe.Pointer(tt.typeOff(m.typ)))
-	} else {
-		rcvrtype = v.typ
-		ms := v.typ.exportedMethods()
-		if uint(i) >= uint(len(ms)) {
-			panic("reflect: internal error: invalid method index")
-		}
-		m := ms[i]
-		if !v.typ.nameOff(m.name).isExported() {
-			panic("reflect: " + op + " of unexported method")
-		}
-		ifn := v.typ.textOff(m.ifn)
-		fn = unsafe.Pointer(&ifn)
-		t = (*funcType)(unsafe.Pointer(v.typ.typeOff(m.mtyp)))
-	}
-	return
-}
-
-// v is a method receiver. Store at p the word which is used to
-// encode that receiver at the start of the argument list.
-// Reflect uses the "interface" calling convention for
-// methods, which always uses one word to record the receiver.
-func storeRcvr(v Value, p unsafe.Pointer) {
-	t := v.typ
-	if t.Kind() == Interface {
-		// the interface data word becomes the receiver word
-		iface := (*nonEmptyInterface)(v.ptr)
-		*(*unsafe.Pointer)(p) = iface.word
-	} else if v.flag&flagIndir != 0 && !ifaceIndir(t) {
-		*(*unsafe.Pointer)(p) = *(*unsafe.Pointer)(v.ptr)
-	} else {
-		*(*unsafe.Pointer)(p) = v.ptr
-	}
-}
-
-// align returns the result of rounding x up to a multiple of n.
-// n must be a power of two.
-func align(x, n uintptr) uintptr {
-	return (x + n - 1) &^ (n - 1)
-}
-
-// callMethod is the call implementation used by a function returned
-// by makeMethodValue (used by v.Method(i).Interface()).
-// It is a streamlined version of the usual reflect call: the caller has
-// already laid out the argument frame for us, so we don't have
-// to deal with individual Values for each argument.
-// It is in this file so that it can be next to the two similar functions above.
-// The remainder of the makeMethodValue implementation is in makefunc.go.
-//
-// NOTE: This function must be marked as a "wrapper" in the generated code,
-// so that the linker can make it work correctly for panic and recover.
-// The gc compilers know to do that for the name "reflect.callMethod".
-//
-// ctxt is the "closure" generated by makeVethodValue.
-// frame is a pointer to the arguments to that closure on the stack.
-// retValid points to a boolean which should be set when the results
-// section of frame is set.
-//
-// regs contains the argument values passed in registers and will contain
-// the values returned from ctxt.fn in registers.
-func callMethod(ctxt *methodValue, frame unsafe.Pointer, retValid *bool, regs *abi.RegArgs) {
-	rcvr := ctxt.rcvr
-	rcvrType, valueFuncType, methodFn := methodReceiver("call", rcvr, ctxt.method)
-
-	// There are two ABIs at play here.
-	//
-	// methodValueCall was invoked with the ABI assuming there was no
-	// receiver ("value ABI") and that's what frame and regs are holding.
-	//
-	// Meanwhile, we need to actually call the method with a receiver, which
-	// has its own ABI ("method ABI"). Everything that follows is a translation
-	// between the two.
-	_, _, valueABI := funcLayout(valueFuncType, nil)
-	valueFrame, valueRegs := frame, regs
-	methodFrameType, methodFramePool, methodABI := funcLayout(valueFuncType, rcvrType)
-
-	// Make a new frame that is one word bigger so we can store the receiver.
-	// This space is used for both arguments and return values.
-	methodFrame := methodFramePool.Get().(unsafe.Pointer)
-	var methodRegs abi.RegArgs
-
-	// Deal with the receiver. It's guaranteed to only be one word in size.
-	if st := methodABI.call.steps[0]; st.kind == abiStepStack {
-		// Only copy the receiver to the stack if the ABI says so.
-		// Otherwise, it'll be in a register already.
-		storeRcvr(rcvr, methodFrame)
-	} else {
-		// Put the receiver in a register.
-		storeRcvr(rcvr, unsafe.Pointer(&methodRegs.Ints))
-	}
-
-	// Translate the rest of the arguments.
-	for i, t := range valueFuncType.in() {
-		valueSteps := valueABI.call.stepsForValue(i)
-		methodSteps := methodABI.call.stepsForValue(i + 1)
-
-		// Zero-sized types are trivial: nothing to do.
-		if len(valueSteps) == 0 {
-			if len(methodSteps) != 0 {
-				panic("method ABI and value ABI do not align")
-			}
-			continue
-		}
-
-		// There are four cases to handle in translating each
-		// argument:
-		// 1. Stack -> stack translation.
-		// 2. Stack -> registers translation.
-		// 3. Registers -> stack translation.
-		// 4. Registers -> registers translation.
-
-		// If the value ABI passes the value on the stack,
-		// then the method ABI does too, because it has strictly
-		// fewer arguments. Simply copy between the two.
-		if vStep := valueSteps[0]; vStep.kind == abiStepStack {
-			mStep := methodSteps[0]
-			// Handle stack -> stack translation.
-			if mStep.kind == abiStepStack {
-				if vStep.size != mStep.size {
-					panic("method ABI and value ABI do not align")
-				}
-				typedmemmove(t,
-					add(methodFrame, mStep.stkOff, "precomputed stack offset"),
-					add(valueFrame, vStep.stkOff, "precomputed stack offset"))
-				continue
-			}
-			// Handle stack -> register translation.
-			for _, mStep := range methodSteps {
-				from := add(valueFrame, vStep.stkOff+mStep.offset, "precomputed stack offset")
-				switch mStep.kind {
-				case abiStepPointer:
-					// Do the pointer copy directly so we get a write barrier.
-					methodRegs.Ptrs[mStep.ireg] = *(*unsafe.Pointer)(from)
-					fallthrough // We need to make sure this ends up in Ints, too.
-				case abiStepIntReg:
-					intToReg(&methodRegs, mStep.ireg, mStep.size, from)
-				case abiStepFloatReg:
-					floatToReg(&methodRegs, mStep.freg, mStep.size, from)
-				default:
-					panic("unexpected method step")
-				}
-			}
-			continue
-		}
-		// Handle register -> stack translation.
-		if mStep := methodSteps[0]; mStep.kind == abiStepStack {
-			for _, vStep := range valueSteps {
-				to := add(methodFrame, mStep.stkOff+vStep.offset, "precomputed stack offset")
-				switch vStep.kind {
-				case abiStepPointer:
-					// Do the pointer copy directly so we get a write barrier.
-					*(*unsafe.Pointer)(to) = valueRegs.Ptrs[vStep.ireg]
-				case abiStepIntReg:
-					intFromReg(valueRegs, vStep.ireg, vStep.size, to)
-				case abiStepFloatReg:
-					floatFromReg(valueRegs, vStep.freg, vStep.size, to)
-				default:
-					panic("unexpected value step")
-				}
-			}
-			continue
-		}
-		// Handle register -> register translation.
-		if len(valueSteps) != len(methodSteps) {
-			// Because it's the same type for the value, and it's assigned
-			// to registers both times, it should always take up the same
-			// number of registers for each ABI.
-			panic("method ABI and value ABI don't align")
-		}
-		for i, vStep := range valueSteps {
-			mStep := methodSteps[i]
-			if mStep.kind != vStep.kind {
-				panic("method ABI and value ABI don't align")
-			}
-			switch vStep.kind {
-			case abiStepPointer:
-				// Copy this too, so we get a write barrier.
-				methodRegs.Ptrs[mStep.ireg] = valueRegs.Ptrs[vStep.ireg]
-				fallthrough
-			case abiStepIntReg:
-				methodRegs.Ints[mStep.ireg] = valueRegs.Ints[vStep.ireg]
-			case abiStepFloatReg:
-				methodRegs.Floats[mStep.freg] = valueRegs.Floats[vStep.freg]
-			default:
-				panic("unexpected value step")
-			}
-		}
-	}
-
-	methodFrameSize := methodFrameType.size
-	// TODO(mknyszek): Remove this when we no longer have
-	// caller reserved spill space.
-	methodFrameSize = align(methodFrameSize, goarch.PtrSize)
-	methodFrameSize += methodABI.spill
-
-	// Mark pointers in registers for the return path.
-	methodRegs.ReturnIsPtr = methodABI.outRegPtrs
-
-	// Call.
-	// Call copies the arguments from scratch to the stack, calls fn,
-	// and then copies the results back into scratch.
-	call(methodFrameType, methodFn, methodFrame, uint32(methodFrameType.size), uint32(methodABI.retOffset), uint32(methodFrameSize), &methodRegs)
-
-	// Copy return values.
-	//
-	// This is somewhat simpler because both ABIs have an identical
-	// return value ABI (the types are identical). As a result, register
-	// results can simply be copied over. Stack-allocated values are laid
-	// out the same, but are at different offsets from the start of the frame
-	// Ignore any changes to args.
-	// Avoid constructing out-of-bounds pointers if there are no return values.
-	// because the arguments may be laid out differently.
-	if valueRegs != nil {
-		*valueRegs = methodRegs
-	}
-	if retSize := methodFrameType.size - methodABI.retOffset; retSize > 0 {
-		valueRet := add(valueFrame, valueABI.retOffset, "valueFrame's size > retOffset")
-		methodRet := add(methodFrame, methodABI.retOffset, "methodFrame's size > retOffset")
-		// This copies to the stack. Write barriers are not needed.
-		memmove(valueRet, methodRet, retSize)
-	}
-
-	// Tell the runtime it can now depend on the return values
-	// being properly initialized.
-	*retValid = true
-
-	// Clear the scratch space and put it back in the pool.
-	// This must happen after the statement above, so that the return
-	// values will always be scanned by someone.
-	typedmemclr(methodFrameType, methodFrame)
-	methodFramePool.Put(methodFrame)
-
-	// See the comment in callReflect.
-	runtime.KeepAlive(ctxt)
-
-	// Keep valueRegs alive because it may hold live pointer results.
-	// The caller (methodValueCall) has it as a stack object, which is only
-	// scanned when there is a reference to it.
-	runtime.KeepAlive(valueRegs)
-}
-
-// funcName returns the name of f, for use in error messages.
-func funcName(f func([]Value) []Value) string {
-	pc := *(*uintptr)(unsafe.Pointer(&f))
-	rf := runtime.FuncForPC(pc)
-	if rf != nil {
-		return rf.Name()
-	}
-	return "closure"
-}
-
-// Cap returns v's capacity.
-// It panics if v's Kind is not Array, Chan, or Slice.
-func (v Value) Cap() int {
-	k := v.kind()
-	switch k {
-	case Array:
-		return v.typ.Len()
-	case Chan:
-		return chancap(v.pointer())
-	case Slice:
-		// Slice is always bigger than a word; assume flagIndir.
-		return (*unsafeheader.Slice)(v.ptr).Cap
-	}
-	panic(&ValueError{"reflect.Value.Cap", v.kind()})
-}
-
-// Close closes the channel v.
-// It panics if v's Kind is not Chan.
-func (v Value) Close() {
-	v.mustBe(Chan)
-	v.mustBeExported()
-	chanclose(v.pointer())
-}
-
-// CanComplex reports whether Complex can be used without panicking.
-func (v Value) CanComplex() bool {
-	switch v.kind() {
-	case Complex64, Complex128:
-		return true
-	default:
-		return false
-	}
-}
-
-// Complex returns v's underlying value, as a complex128.
-// It panics if v's Kind is not Complex64 or Complex128
-func (v Value) Complex() complex128 {
-	k := v.kind()
-	switch k {
-	case Complex64:
-		return complex128(*(*complex64)(v.ptr))
-	case Complex128:
-		return *(*complex128)(v.ptr)
-	}
-	panic(&ValueError{"reflect.Value.Complex", v.kind()})
-}
-
-// Elem returns the value that the interface v contains
-// or that the pointer v points to.
-// It panics if v's Kind is not Interface or Pointer.
-// It returns the zero Value if v is nil.
-func (v Value) Elem() Value {
-	k := v.kind()
-	switch k {
-	case Interface:
-		var eface any
-		if v.typ.NumMethod() == 0 {
-			eface = *(*any)(v.ptr)
-		} else {
-			eface = (any)(*(*interface {
-				M()
-			})(v.ptr))
-		}
-		x := unpackEface(eface)
-		if x.flag != 0 {
-			x.flag |= v.flag.ro()
-		}
-		return x
-	case Pointer:
-		ptr := v.ptr
-		if v.flag&flagIndir != 0 {
-			if ifaceIndir(v.typ) {
-				// This is a pointer to a not-in-heap object. ptr points to a uintptr
-				// in the heap. That uintptr is the address of a not-in-heap object.
-				// In general, pointers to not-in-heap objects can be total junk.
-				// But Elem() is asking to dereference it, so the user has asserted
-				// that at least it is a valid pointer (not just an integer stored in
-				// a pointer slot). So let's check, to make sure that it isn't a pointer
-				// that the runtime will crash on if it sees it during GC or write barriers.
-				// Since it is a not-in-heap pointer, all pointers to the heap are
-				// forbidden! That makes the test pretty easy.
-				// See issue 48399.
-				if !verifyNotInHeapPtr(*(*uintptr)(ptr)) {
-					panic("reflect: reflect.Value.Elem on an invalid notinheap pointer")
-				}
-			}
-			ptr = *(*unsafe.Pointer)(ptr)
-		}
-		// The returned value's address is v's value.
-		if ptr == nil {
-			return Value{}
-		}
-		tt := (*ptrType)(unsafe.Pointer(v.typ))
-		typ := tt.elem
-		fl := v.flag&flagRO | flagIndir | flagAddr
-		fl |= flag(typ.Kind())
-		return Value{typ, ptr, fl}
-	}
-	panic(&ValueError{"reflect.Value.Elem", v.kind()})
-}
-
-// Field returns the i'th field of the struct v.
-// It panics if v's Kind is not Struct or i is out of range.
-func (v Value) Field(i int) Value {
-	if v.kind() != Struct {
-		panic(&ValueError{"reflect.Value.Field", v.kind()})
-	}
-	tt := (*structType)(unsafe.Pointer(v.typ))
-	if uint(i) >= uint(len(tt.fields)) {
-		panic("reflect: Field index out of range")
-	}
-	field := &tt.fields[i]
-	typ := field.typ
-
-	// Inherit permission bits from v, but clear flagEmbedRO.
-	fl := v.flag&(flagStickyRO|flagIndir|flagAddr) | flag(typ.Kind())
-	// Using an unexported field forces flagRO.
-	if !field.name.isExported() {
-		if field.embedded() {
-			fl |= flagEmbedRO
-		} else {
-			fl |= flagStickyRO
-		}
-	}
-	// Either flagIndir is set and v.ptr points at struct,
-	// or flagIndir is not set and v.ptr is the actual struct data.
-	// In the former case, we want v.ptr + offset.
-	// In the latter case, we must have field.offset = 0,
-	// so v.ptr + field.offset is still the correct address.
-	ptr := add(v.ptr, field.offset(), "same as non-reflect &v.field")
-	return Value{typ, ptr, fl}
-}
-
-// FieldByIndex returns the nested field corresponding to index.
-// It panics if evaluation requires stepping through a nil
-// pointer or a field that is not a struct.
-func (v Value) FieldByIndex(index []int) Value {
-	if len(index) == 1 {
-		return v.Field(index[0])
-	}
-	v.mustBe(Struct)
-	for i, x := range index {
-		if i > 0 {
-			if v.Kind() == Pointer && v.typ.Elem().Kind() == Struct {
-				if v.IsNil() {
-					panic("reflect: indirection through nil pointer to embedded struct")
-				}
-				v = v.Elem()
-			}
-		}
-		v = v.Field(x)
-	}
-	return v
-}
-
-// FieldByIndexErr returns the nested field corresponding to index.
-// It returns an error if evaluation requires stepping through a nil
-// pointer, but panics if it must step through a field that
-// is not a struct.
-func (v Value) FieldByIndexErr(index []int) (Value, error) {
-	if len(index) == 1 {
-		return v.Field(index[0]), nil
-	}
-	v.mustBe(Struct)
-	for i, x := range index {
-		if i > 0 {
-			if v.Kind() == Ptr && v.typ.Elem().Kind() == Struct {
-				if v.IsNil() {
-					return Value{}, errors.New("reflect: indirection through nil pointer to embedded struct field " + v.typ.Elem().Name())
-				}
-				v = v.Elem()
-			}
-		}
-		v = v.Field(x)
-	}
-	return v, nil
-}
-
-// FieldByName returns the struct field with the given name.
-// It returns the zero Value if no field was found.
-// It panics if v's Kind is not struct.
-func (v Value) FieldByName(name string) Value {
-	v.mustBe(Struct)
-	if f, ok := v.typ.FieldByName(name); ok {
-		return v.FieldByIndex(f.Index)
-	}
-	return Value{}
-}
-
-// FieldByNameFunc returns the struct field with a name
-// that satisfies the match function.
-// It panics if v's Kind is not struct.
-// It returns the zero Value if no field was found.
-func (v Value) FieldByNameFunc(match func(string) bool) Value {
-	if f, ok := v.typ.FieldByNameFunc(match); ok {
-		return v.FieldByIndex(f.Index)
-	}
-	return Value{}
-}
-
-// CanFloat reports whether Float can be used without panicking.
-func (v Value) CanFloat() bool {
-	switch v.kind() {
-	case Float32, Float64:
-		return true
-	default:
-		return false
-	}
-}
-
-// Float returns v's underlying value, as a float64.
-// It panics if v's Kind is not Float32 or Float64
-func (v Value) Float() float64 {
-	k := v.kind()
-	switch k {
-	case Float32:
-		return float64(*(*float32)(v.ptr))
-	case Float64:
-		return *(*float64)(v.ptr)
-	}
-	panic(&ValueError{"reflect.Value.Float", v.kind()})
-}
-
-var uint8Type = TypeOf(uint8(0)).(*rtype)
-
-// Index returns v's i'th element.
-// It panics if v's Kind is not Array, Slice, or String or i is out of range.
-func (v Value) Index(i int) Value {
-	switch v.kind() {
-	case Array:
-		tt := (*arrayType)(unsafe.Pointer(v.typ))
-		if uint(i) >= uint(tt.len) {
-			panic("reflect: array index out of range")
-		}
-		typ := tt.elem
-		offset := uintptr(i) * typ.size
-
-		// Either flagIndir is set and v.ptr points at array,
-		// or flagIndir is not set and v.ptr is the actual array data.
-		// In the former case, we want v.ptr + offset.
-		// In the latter case, we must be doing Index(0), so offset = 0,
-		// so v.ptr + offset is still the correct address.
-		val := add(v.ptr, offset, "same as &v[i], i < tt.len")
-		fl := v.flag&(flagIndir|flagAddr) | v.flag.ro() | flag(typ.Kind()) // bits same as overall array
-		return Value{typ, val, fl}
-
-	case Slice:
-		// Element flag same as Elem of Pointer.
-		// Addressable, indirect, possibly read-only.
-		s := (*unsafeheader.Slice)(v.ptr)
-		if uint(i) >= uint(s.Len) {
-			panic("reflect: slice index out of range")
-		}
-		tt := (*sliceType)(unsafe.Pointer(v.typ))
-		typ := tt.elem
-		val := arrayAt(s.Data, i, typ.size, "i < s.Len")
-		fl := flagAddr | flagIndir | v.flag.ro() | flag(typ.Kind())
-		return Value{typ, val, fl}
-
-	case String:
-		s := (*unsafeheader.String)(v.ptr)
-		if uint(i) >= uint(s.Len) {
-			panic("reflect: string index out of range")
-		}
-		p := arrayAt(s.Data, i, 1, "i < s.Len")
-		fl := v.flag.ro() | flag(Uint8) | flagIndir
-		return Value{uint8Type, p, fl}
-	}
-	panic(&ValueError{"reflect.Value.Index", v.kind()})
-}
-
-// CanInt reports whether Int can be used without panicking.
-func (v Value) CanInt() bool {
-	switch v.kind() {
-	case Int, Int8, Int16, Int32, Int64:
-		return true
-	default:
-		return false
-	}
-}
-
-// Int returns v's underlying value, as an int64.
-// It panics if v's Kind is not Int, Int8, Int16, Int32, or Int64.
-func (v Value) Int() int64 {
-	k := v.kind()
-	p := v.ptr
-	switch k {
-	case Int:
-		return int64(*(*int)(p))
-	case Int8:
-		return int64(*(*int8)(p))
-	case Int16:
-		return int64(*(*int16)(p))
-	case Int32:
-		return int64(*(*int32)(p))
-	case Int64:
-		return *(*int64)(p)
-	}
-	panic(&ValueError{"reflect.Value.Int", v.kind()})
-}
-
-// CanInterface reports whether Interface can be used without panicking.
-func (v Value) CanInterface() bool {
-	if v.flag == 0 {
-		panic(&ValueError{"reflect.Value.CanInterface", Invalid})
-	}
-	return v.flag&flagRO == 0
-}
-
-// Interface returns v's current value as an interface{}.
-// It is equivalent to:
-//	var i interface{} = (v's underlying value)
-// It panics if the Value was obtained by accessing
-// unexported struct fields.
-func (v Value) Interface() (i any) {
-	return valueInterface(v, true)
-}
-
-func valueInterface(v Value, safe bool) any {
-	if v.flag == 0 {
-		panic(&ValueError{"reflect.Value.Interface", Invalid})
-	}
-	if safe && v.flag&flagRO != 0 {
-		// Do not allow access to unexported values via Interface,
-		// because they might be pointers that should not be
-		// writable or methods or function that should not be callable.
-		panic("reflect.Value.Interface: cannot return value obtained from unexported field or method")
-	}
-	if v.flag&flagMethod != 0 {
-		v = makeMethodValue("Interface", v)
-	}
-
-	if v.kind() == Interface {
-		// Special case: return the element inside the interface.
-		// Empty interface has one layout, all interfaces with
-		// methods have a second layout.
-		if v.NumMethod() == 0 {
-			return *(*any)(v.ptr)
-		}
-		return *(*interface {
-			M()
-		})(v.ptr)
-	}
-
-	// TODO: pass safe to packEface so we don't need to copy if safe==true?
-	return packEface(v)
-}
-
-// InterfaceData returns a pair of unspecified uintptr values.
-// It panics if v's Kind is not Interface.
-//
-// In earlier versions of Go, this function returned the interface's
-// value as a uintptr pair. As of Go 1.4, the implementation of
-// interface values precludes any defined use of InterfaceData.
-//
-// Deprecated: The memory representation of interface values is not
-// compatible with InterfaceData.
-func (v Value) InterfaceData() [2]uintptr {
-	v.mustBe(Interface)
-	// We treat this as a read operation, so we allow
-	// it even for unexported data, because the caller
-	// has to import "unsafe" to turn it into something
-	// that can be abused.
-	// Interface value is always bigger than a word; assume flagIndir.
-	return *(*[2]uintptr)(v.ptr)
-}
-
-// IsNil reports whether its argument v is nil. The argument must be
-// a chan, func, interface, map, pointer, or slice value; if it is
-// not, IsNil panics. Note that IsNil is not always equivalent to a
-// regular comparison with nil in Go. For example, if v was created
-// by calling ValueOf with an uninitialized interface variable i,
-// i==nil will be true but v.IsNil will panic as v will be the zero
-// Value.
-func (v Value) IsNil() bool {
-	k := v.kind()
-	switch k {
-	case Chan, Func, Map, Pointer, UnsafePointer:
-		if v.flag&flagMethod != 0 {
-			return false
-		}
-		ptr := v.ptr
-		if v.flag&flagIndir != 0 {
-			ptr = *(*unsafe.Pointer)(ptr)
-		}
-		return ptr == nil
-	case Interface, Slice:
-		// Both interface and slice are nil if first word is 0.
-		// Both are always bigger than a word; assume flagIndir.
-		return *(*unsafe.Pointer)(v.ptr) == nil
-	}
-	panic(&ValueError{"reflect.Value.IsNil", v.kind()})
-}
-
-// IsValid reports whether v represents a value.
-// It returns false if v is the zero Value.
-// If IsValid returns false, all other methods except String panic.
-// Most functions and methods never return an invalid Value.
-// If one does, its documentation states the conditions explicitly.
-func (v Value) IsValid() bool {
-	return v.flag != 0
-}
-
-// IsZero reports whether v is the zero value for its type.
-// It panics if the argument is invalid.
-func (v Value) IsZero() bool {
-	switch v.kind() {
-	case Bool:
-		return !v.Bool()
-	case Int, Int8, Int16, Int32, Int64:
-		return v.Int() == 0
-	case Uint, Uint8, Uint16, Uint32, Uint64, Uintptr:
-		return v.Uint() == 0
-	case Float32, Float64:
-		return math.Float64bits(v.Float()) == 0
-	case Complex64, Complex128:
-		c := v.Complex()
-		return math.Float64bits(real(c)) == 0 && math.Float64bits(imag(c)) == 0
-	case Array:
-		for i := 0; i < v.Len(); i++ {
-			if !v.Index(i).IsZero() {
-				return false
-			}
-		}
-		return true
-	case Chan, Func, Interface, Map, Pointer, Slice, UnsafePointer:
-		return v.IsNil()
-	case String:
-		return v.Len() == 0
-	case Struct:
-		for i := 0; i < v.NumField(); i++ {
-			if !v.Field(i).IsZero() {
-				return false
-			}
-		}
-		return true
-	default:
-		// This should never happens, but will act as a safeguard for
-		// later, as a default value doesn't makes sense here.
-		panic(&ValueError{"reflect.Value.IsZero", v.Kind()})
-	}
-}
-
-// Kind returns v's Kind.
-// If v is the zero Value (IsValid returns false), Kind returns Invalid.
-func (v Value) Kind() Kind {
-	return v.kind()
-}
-
-// Len returns v's length.
-// It panics if v's Kind is not Array, Chan, Map, Slice, or String.
-func (v Value) Len() int {
-	k := v.kind()
-	switch k {
-	case Array:
-		tt := (*arrayType)(unsafe.Pointer(v.typ))
-		return int(tt.len)
-	case Chan:
-		return chanlen(v.pointer())
-	case Map:
-		return maplen(v.pointer())
-	case Slice:
-		// Slice is bigger than a word; assume flagIndir.
-		return (*unsafeheader.Slice)(v.ptr).Len
-	case String:
-		// String is bigger than a word; assume flagIndir.
-		return (*unsafeheader.String)(v.ptr).Len
-	}
-	panic(&ValueError{"reflect.Value.Len", v.kind()})
-}
-
-var stringType = TypeOf("").(*rtype)
-
-// MapIndex returns the value associated with key in the map v.
-// It panics if v's Kind is not Map.
-// It returns the zero Value if key is not found in the map or if v represents a nil map.
-// As in Go, the key's value must be assignable to the map's key type.
-func (v Value) MapIndex(key Value) Value {
-	v.mustBe(Map)
-	tt := (*mapType)(unsafe.Pointer(v.typ))
-
-	// Do not require key to be exported, so that DeepEqual
-	// and other programs can use all the keys returned by
-	// MapKeys as arguments to MapIndex. If either the map
-	// or the key is unexported, though, the result will be
-	// considered unexported. This is consistent with the
-	// behavior for structs, which allow read but not write
-	// of unexported fields.
-
-	var e unsafe.Pointer
-	if (tt.key == stringType || key.kind() == String) && tt.key == key.typ && tt.elem.size <= maxValSize {
-		k := *(*string)(key.ptr)
-		e = mapaccess_faststr(v.typ, v.pointer(), k)
-	} else {
-		key = key.assignTo("reflect.Value.MapIndex", tt.key, nil)
-		var k unsafe.Pointer
-		if key.flag&flagIndir != 0 {
-			k = key.ptr
-		} else {
-			k = unsafe.Pointer(&key.ptr)
-		}
-		e = mapaccess(v.typ, v.pointer(), k)
-	}
-	if e == nil {
-		return Value{}
-	}
-	typ := tt.elem
-	fl := (v.flag | key.flag).ro()
-	fl |= flag(typ.Kind())
-	return copyVal(typ, fl, e)
-}
-
-// MapKeys returns a slice containing all the keys present in the map,
-// in unspecified order.
-// It panics if v's Kind is not Map.
-// It returns an empty slice if v represents a nil map.
-func (v Value) MapKeys() []Value {
-	v.mustBe(Map)
-	tt := (*mapType)(unsafe.Pointer(v.typ))
-	keyType := tt.key
-
-	fl := v.flag.ro() | flag(keyType.Kind())
-
-	m := v.pointer()
-	mlen := int(0)
-	if m != nil {
-		mlen = maplen(m)
-	}
-	var it hiter
-	mapiterinit(v.typ, m, &it)
-	a := make([]Value, mlen)
-	var i int
-	for i = 0; i < len(a); i++ {
-		key := mapiterkey(&it)
-		if key == nil {
-			// Someone deleted an entry from the map since we
-			// called maplen above. It's a data race, but nothing
-			// we can do about it.
-			break
-		}
-		a[i] = copyVal(keyType, fl, key)
-		mapiternext(&it)
-	}
-	return a[:i]
-}
-
-// hiter's structure matches runtime.hiter's structure.
-// Having a clone here allows us to embed a map iterator
-// inside type MapIter so that MapIters can be re-used
-// without doing any allocations.
-type hiter struct {
-	key         unsafe.Pointer
-	elem        unsafe.Pointer
-	t           unsafe.Pointer
-	h           unsafe.Pointer
-	buckets     unsafe.Pointer
-	bptr        unsafe.Pointer
-	overflow    *[]unsafe.Pointer
-	oldoverflow *[]unsafe.Pointer
-	startBucket uintptr
-	offset      uint8
-	wrapped     bool
-	B           uint8
-	i           uint8
-	bucket      uintptr
-	checkBucket uintptr
-}
-
-func (h *hiter) initialized() bool {
-	return h.t != nil
-}
-
-// A MapIter is an iterator for ranging over a map.
-// See Value.MapRange.
-type MapIter struct {
-	m     Value
-	hiter hiter
-}
-
-// Key returns the key of iter's current map entry.
-func (iter *MapIter) Key() Value {
-	if !iter.hiter.initialized() {
-		panic("MapIter.Key called before Next")
-	}
-	iterkey := mapiterkey(&iter.hiter)
-	if iterkey == nil {
-		panic("MapIter.Key called on exhausted iterator")
-	}
-
-	t := (*mapType)(unsafe.Pointer(iter.m.typ))
-	ktype := t.key
-	return copyVal(ktype, iter.m.flag.ro()|flag(ktype.Kind()), iterkey)
-}
-
-// SetIterKey assigns to v the key of iter's current map entry.
-// It is equivalent to v.Set(iter.Key()), but it avoids allocating a new Value.
-// As in Go, the key must be assignable to v's type.
-func (v Value) SetIterKey(iter *MapIter) {
-	if !iter.hiter.initialized() {
-		panic("reflect: Value.SetIterKey called before Next")
-	}
-	iterkey := mapiterkey(&iter.hiter)
-	if iterkey == nil {
-		panic("reflect: Value.SetIterKey called on exhausted iterator")
-	}
-
-	v.mustBeAssignable()
-	var target unsafe.Pointer
-	if v.kind() == Interface {
-		target = v.ptr
-	}
-
-	t := (*mapType)(unsafe.Pointer(iter.m.typ))
-	ktype := t.key
-
-	key := Value{ktype, iterkey, iter.m.flag | flag(ktype.Kind()) | flagIndir}
-	key = key.assignTo("reflect.MapIter.SetKey", v.typ, target)
-	typedmemmove(v.typ, v.ptr, key.ptr)
-}
-
-// Value returns the value of iter's current map entry.
-func (iter *MapIter) Value() Value {
-	if !iter.hiter.initialized() {
-		panic("MapIter.Value called before Next")
-	}
-	iterelem := mapiterelem(&iter.hiter)
-	if iterelem == nil {
-		panic("MapIter.Value called on exhausted iterator")
-	}
-
-	t := (*mapType)(unsafe.Pointer(iter.m.typ))
-	vtype := t.elem
-	return copyVal(vtype, iter.m.flag.ro()|flag(vtype.Kind()), iterelem)
-}
-
-// SetIterValue assigns to v the value of iter's current map entry.
-// It is equivalent to v.Set(iter.Value()), but it avoids allocating a new Value.
-// As in Go, the value must be assignable to v's type.
-func (v Value) SetIterValue(iter *MapIter) {
-	if !iter.hiter.initialized() {
-		panic("reflect: Value.SetIterValue called before Next")
-	}
-	iterelem := mapiterelem(&iter.hiter)
-	if iterelem == nil {
-		panic("reflect: Value.SetIterValue called on exhausted iterator")
-	}
-
-	v.mustBeAssignable()
-	var target unsafe.Pointer
-	if v.kind() == Interface {
-		target = v.ptr
-	}
-
-	t := (*mapType)(unsafe.Pointer(iter.m.typ))
-	vtype := t.elem
-
-	elem := Value{vtype, iterelem, iter.m.flag | flag(vtype.Kind()) | flagIndir}
-	elem = elem.assignTo("reflect.MapIter.SetValue", v.typ, target)
-	typedmemmove(v.typ, v.ptr, elem.ptr)
-}
-
-// Next advances the map iterator and reports whether there is another
-// entry. It returns false when iter is exhausted; subsequent
-// calls to Key, Value, or Next will panic.
-func (iter *MapIter) Next() bool {
-	if !iter.m.IsValid() {
-		panic("MapIter.Next called on an iterator that does not have an associated map Value")
-	}
-	if !iter.hiter.initialized() {
-		mapiterinit(iter.m.typ, iter.m.pointer(), &iter.hiter)
-	} else {
-		if mapiterkey(&iter.hiter) == nil {
-			panic("MapIter.Next called on exhausted iterator")
-		}
-		mapiternext(&iter.hiter)
-	}
-	return mapiterkey(&iter.hiter) != nil
-}
-
-// Reset modifies iter to iterate over v.
-// It panics if v's Kind is not Map and v is not the zero Value.
-// Reset(Value{}) causes iter to not to refer to any map,
-// which may allow the previously iterated-over map to be garbage collected.
-func (iter *MapIter) Reset(v Value) {
-	if v.IsValid() {
-		v.mustBe(Map)
-	}
-	iter.m = v
-	iter.hiter = hiter{}
-}
-
-// MapRange returns a range iterator for a map.
-// It panics if v's Kind is not Map.
-//
-// Call Next to advance the iterator, and Key/Value to access each entry.
-// Next returns false when the iterator is exhausted.
-// MapRange follows the same iteration semantics as a range statement.
-//
-// Example:
-//
-//	iter := reflect.ValueOf(m).MapRange()
-// 	for iter.Next() {
-//		k := iter.Key()
-//		v := iter.Value()
-//		...
-//	}
-//
-func (v Value) MapRange() *MapIter {
-	v.mustBe(Map)
-	return &MapIter{m: v}
-}
-
-// copyVal returns a Value containing the map key or value at ptr,
-// allocating a new variable as needed.
-func copyVal(typ *rtype, fl flag, ptr unsafe.Pointer) Value {
-	if ifaceIndir(typ) {
-		// Copy result so future changes to the map
-		// won't change the underlying value.
-		c := unsafe_New(typ)
-		typedmemmove(typ, c, ptr)
-		return Value{typ, c, fl | flagIndir}
-	}
-	return Value{typ, *(*unsafe.Pointer)(ptr), fl}
-}
-
-// Method returns a function value corresponding to v's i'th method.
-// The arguments to a Call on the returned function should not include
-// a receiver; the returned function will always use v as the receiver.
-// Method panics if i is out of range or if v is a nil interface value.
-func (v Value) Method(i int) Value {
-	if v.typ == nil {
-		panic(&ValueError{"reflect.Value.Method", Invalid})
-	}
-	if v.flag&flagMethod != 0 || uint(i) >= uint(v.typ.NumMethod()) {
-		panic("reflect: Method index out of range")
-	}
-	if v.typ.Kind() == Interface && v.IsNil() {
-		panic("reflect: Method on nil interface value")
-	}
-	fl := v.flag.ro() | (v.flag & flagIndir)
-	fl |= flag(Func)
-	fl |= flag(i)<<flagMethodShift | flagMethod
-	return Value{v.typ, v.ptr, fl}
-}
-
-// NumMethod returns the number of exported methods in the value's method set.
-func (v Value) NumMethod() int {
-	if v.typ == nil {
-		panic(&ValueError{"reflect.Value.NumMethod", Invalid})
-	}
-	if v.flag&flagMethod != 0 {
-		return 0
-	}
-	return v.typ.NumMethod()
-}
-
-// MethodByName returns a function value corresponding to the method
-// of v with the given name.
-// The arguments to a Call on the returned function should not include
-// a receiver; the returned function will always use v as the receiver.
-// It returns the zero Value if no method was found.
-func (v Value) MethodByName(name string) Value {
-	if v.typ == nil {
-		panic(&ValueError{"reflect.Value.MethodByName", Invalid})
-	}
-	if v.flag&flagMethod != 0 {
-		return Value{}
-	}
-	m, ok := v.typ.MethodByName(name)
-	if !ok {
-		return Value{}
-	}
-	return v.Method(m.Index)
-}
-
-// NumField returns the number of fields in the struct v.
-// It panics if v's Kind is not Struct.
-func (v Value) NumField() int {
-	v.mustBe(Struct)
-	tt := (*structType)(unsafe.Pointer(v.typ))
-	return len(tt.fields)
-}
-
-// OverflowComplex reports whether the complex128 x cannot be represented by v's type.
-// It panics if v's Kind is not Complex64 or Complex128.
-func (v Value) OverflowComplex(x complex128) bool {
-	k := v.kind()
-	switch k {
-	case Complex64:
-		return overflowFloat32(real(x)) || overflowFloat32(imag(x))
-	case Complex128:
-		return false
-	}
-	panic(&ValueError{"reflect.Value.OverflowComplex", v.kind()})
-}
-
-// OverflowFloat reports whether the float64 x cannot be represented by v's type.
-// It panics if v's Kind is not Float32 or Float64.
-func (v Value) OverflowFloat(x float64) bool {
-	k := v.kind()
-	switch k {
-	case Float32:
-		return overflowFloat32(x)
-	case Float64:
-		return false
-	}
-	panic(&ValueError{"reflect.Value.OverflowFloat", v.kind()})
-}
-
-func overflowFloat32(x float64) bool {
-	if x < 0 {
-		x = -x
-	}
-	return math.MaxFloat32 < x && x <= math.MaxFloat64
-}
-
-// OverflowInt reports whether the int64 x cannot be represented by v's type.
-// It panics if v's Kind is not Int, Int8, Int16, Int32, or Int64.
-func (v Value) OverflowInt(x int64) bool {
-	k := v.kind()
-	switch k {
-	case Int, Int8, Int16, Int32, Int64:
-		bitSize := v.typ.size * 8
-		trunc := (x << (64 - bitSize)) >> (64 - bitSize)
-		return x != trunc
-	}
-	panic(&ValueError{"reflect.Value.OverflowInt", v.kind()})
-}
-
-// OverflowUint reports whether the uint64 x cannot be represented by v's type.
-// It panics if v's Kind is not Uint, Uintptr, Uint8, Uint16, Uint32, or Uint64.
-func (v Value) OverflowUint(x uint64) bool {
-	k := v.kind()
-	switch k {
-	case Uint, Uintptr, Uint8, Uint16, Uint32, Uint64:
-		bitSize := v.typ.size * 8
-		trunc := (x << (64 - bitSize)) >> (64 - bitSize)
-		return x != trunc
-	}
-	panic(&ValueError{"reflect.Value.OverflowUint", v.kind()})
-}
-
-//go:nocheckptr
-// This prevents inlining Value.Pointer when -d=checkptr is enabled,
-// which ensures cmd/compile can recognize unsafe.Pointer(v.Pointer())
-// and make an exception.
-
-// Pointer returns v's value as a uintptr.
-// It returns uintptr instead of unsafe.Pointer so that
-// code using reflect cannot obtain unsafe.Pointers
-// without importing the unsafe package explicitly.
-// It panics if v's Kind is not Chan, Func, Map, Pointer, Slice, or UnsafePointer.
-//
-// If v's Kind is Func, the returned pointer is an underlying
-// code pointer, but not necessarily enough to identify a
-// single function uniquely. The only guarantee is that the
-// result is zero if and only if v is a nil func Value.
-//
-// If v's Kind is Slice, the returned pointer is to the first
-// element of the slice. If the slice is nil the returned value
-// is 0.  If the slice is empty but non-nil the return value is non-zero.
-//
-// It's preferred to use uintptr(Value.UnsafePointer()) to get the equivalent result.
-func (v Value) Pointer() uintptr {
-	k := v.kind()
-	switch k {
-	case Pointer:
-		if v.typ.ptrdata == 0 {
-			val := *(*uintptr)(v.ptr)
-			// Since it is a not-in-heap pointer, all pointers to the heap are
-			// forbidden! See comment in Value.Elem and issue #48399.
-			if !verifyNotInHeapPtr(val) {
-				panic("reflect: reflect.Value.Pointer on an invalid notinheap pointer")
-			}
-			return val
-		}
-		fallthrough
-	case Chan, Map, UnsafePointer:
-		return uintptr(v.pointer())
-	case Func:
-		if v.flag&flagMethod != 0 {
-			// As the doc comment says, the returned pointer is an
-			// underlying code pointer but not necessarily enough to
-			// identify a single function uniquely. All method expressions
-			// created via reflect have the same underlying code pointer,
-			// so their Pointers are equal. The function used here must
-			// match the one used in makeMethodValue.
-			return methodValueCallCodePtr()
-		}
-		p := v.pointer()
-		// Non-nil func value points at data block.
-		// First word of data block is actual code.
-		if p != nil {
-			p = *(*unsafe.Pointer)(p)
-		}
-		return uintptr(p)
-
-	case Slice:
-		return (*SliceHeader)(v.ptr).Data
-	}
-	panic(&ValueError{"reflect.Value.Pointer", v.kind()})
-}
-
-// Recv receives and returns a value from the channel v.
-// It panics if v's Kind is not Chan.
-// The receive blocks until a value is ready.
-// The boolean value ok is true if the value x corresponds to a send
-// on the channel, false if it is a zero value received because the channel is closed.
-func (v Value) Recv() (x Value, ok bool) {
-	v.mustBe(Chan)
-	v.mustBeExported()
-	return v.recv(false)
-}
-
-// internal recv, possibly non-blocking (nb).
-// v is known to be a channel.
-func (v Value) recv(nb bool) (val Value, ok bool) {
-	tt := (*chanType)(unsafe.Pointer(v.typ))
-	if ChanDir(tt.dir)&RecvDir == 0 {
-		panic("reflect: recv on send-only channel")
-	}
-	t := tt.elem
-	val = Value{t, nil, flag(t.Kind())}
-	var p unsafe.Pointer
-	if ifaceIndir(t) {
-		p = unsafe_New(t)
-		val.ptr = p
-		val.flag |= flagIndir
-	} else {
-		p = unsafe.Pointer(&val.ptr)
-	}
-	selected, ok := chanrecv(v.pointer(), nb, p)
-	if !selected {
-		val = Value{}
-	}
-	return
-}
-
-// Send sends x on the channel v.
-// It panics if v's kind is not Chan or if x's type is not the same type as v's element type.
-// As in Go, x's value must be assignable to the channel's element type.
-func (v Value) Send(x Value) {
-	v.mustBe(Chan)
-	v.mustBeExported()
-	v.send(x, false)
-}
-
-// internal send, possibly non-blocking.
-// v is known to be a channel.
-func (v Value) send(x Value, nb bool) (selected bool) {
-	tt := (*chanType)(unsafe.Pointer(v.typ))
-	if ChanDir(tt.dir)&SendDir == 0 {
-		panic("reflect: send on recv-only channel")
-	}
-	x.mustBeExported()
-	x = x.assignTo("reflect.Value.Send", tt.elem, nil)
-	var p unsafe.Pointer
-	if x.flag&flagIndir != 0 {
-		p = x.ptr
-	} else {
-		p = unsafe.Pointer(&x.ptr)
-	}
-	return chansend(v.pointer(), p, nb)
-}
-
-// Set assigns x to the value v.
-// It panics if CanSet returns false.
-// As in Go, x's value must be assignable to v's type.
-func (v Value) Set(x Value) {
-	v.mustBeAssignable()
-	x.mustBeExported() // do not let unexported x leak
-	var target unsafe.Pointer
-	if v.kind() == Interface {
-		target = v.ptr
-	}
-	x = x.assignTo("reflect.Set", v.typ, target)
-	if x.flag&flagIndir != 0 {
-		if x.ptr == unsafe.Pointer(&zeroVal[0]) {
-			typedmemclr(v.typ, v.ptr)
-		} else {
-			typedmemmove(v.typ, v.ptr, x.ptr)
-		}
-	} else {
-		*(*unsafe.Pointer)(v.ptr) = x.ptr
-	}
-}
-
-// SetBool sets v's underlying value.
-// It panics if v's Kind is not Bool or if CanSet() is false.
-func (v Value) SetBool(x bool) {
-	v.mustBeAssignable()
-	v.mustBe(Bool)
-	*(*bool)(v.ptr) = x
-}
-
-// SetBytes sets v's underlying value.
-// It panics if v's underlying value is not a slice of bytes.
-func (v Value) SetBytes(x []byte) {
-	v.mustBeAssignable()
-	v.mustBe(Slice)
-	if v.typ.Elem().Kind() != Uint8 {
-		panic("reflect.Value.SetBytes of non-byte slice")
-	}
-	*(*[]byte)(v.ptr) = x
-}
-
-// setRunes sets v's underlying value.
-// It panics if v's underlying value is not a slice of runes (int32s).
-func (v Value) setRunes(x []rune) {
-	v.mustBeAssignable()
-	v.mustBe(Slice)
-	if v.typ.Elem().Kind() != Int32 {
-		panic("reflect.Value.setRunes of non-rune slice")
-	}
-	*(*[]rune)(v.ptr) = x
-}
-
-// SetComplex sets v's underlying value to x.
-// It panics if v's Kind is not Complex64 or Complex128, or if CanSet() is false.
-func (v Value) SetComplex(x complex128) {
-	v.mustBeAssignable()
-	switch k := v.kind(); k {
-	default:
-		panic(&ValueError{"reflect.Value.SetComplex", v.kind()})
-	case Complex64:
-		*(*complex64)(v.ptr) = complex64(x)
-	case Complex128:
-		*(*complex128)(v.ptr) = x
-	}
-}
-
-// SetFloat sets v's underlying value to x.
-// It panics if v's Kind is not Float32 or Float64, or if CanSet() is false.
-func (v Value) SetFloat(x float64) {
-	v.mustBeAssignable()
-	switch k := v.kind(); k {
-	default:
-		panic(&ValueError{"reflect.Value.SetFloat", v.kind()})
-	case Float32:
-		*(*float32)(v.ptr) = float32(x)
-	case Float64:
-		*(*float64)(v.ptr) = x
-	}
-}
-
-// SetInt sets v's underlying value to x.
-// It panics if v's Kind is not Int, Int8, Int16, Int32, or Int64, or if CanSet() is false.
-func (v Value) SetInt(x int64) {
-	v.mustBeAssignable()
-	switch k := v.kind(); k {
-	default:
-		panic(&ValueError{"reflect.Value.SetInt", v.kind()})
-	case Int:
-		*(*int)(v.ptr) = int(x)
-	case Int8:
-		*(*int8)(v.ptr) = int8(x)
-	case Int16:
-		*(*int16)(v.ptr) = int16(x)
-	case Int32:
-		*(*int32)(v.ptr) = int32(x)
-	case Int64:
-		*(*int64)(v.ptr) = x
-	}
-}
-
-// SetLen sets v's length to n.
-// It panics if v's Kind is not Slice or if n is negative or
-// greater than the capacity of the slice.
-func (v Value) SetLen(n int) {
-	v.mustBeAssignable()
-	v.mustBe(Slice)
-	s := (*unsafeheader.Slice)(v.ptr)
-	if uint(n) > uint(s.Cap) {
-		panic("reflect: slice length out of range in SetLen")
-	}
-	s.Len = n
-}
-
-// SetCap sets v's capacity to n.
-// It panics if v's Kind is not Slice or if n is smaller than the length or
-// greater than the capacity of the slice.
-func (v Value) SetCap(n int) {
-	v.mustBeAssignable()
-	v.mustBe(Slice)
-	s := (*unsafeheader.Slice)(v.ptr)
-	if n < s.Len || n > s.Cap {
-		panic("reflect: slice capacity out of range in SetCap")
-	}
-	s.Cap = n
-}
-
-// SetMapIndex sets the element associated with key in the map v to elem.
-// It panics if v's Kind is not Map.
-// If elem is the zero Value, SetMapIndex deletes the key from the map.
-// Otherwise if v holds a nil map, SetMapIndex will panic.
-// As in Go, key's elem must be assignable to the map's key type,
-// and elem's value must be assignable to the map's elem type.
-func (v Value) SetMapIndex(key, elem Value) {
-	v.mustBe(Map)
-	v.mustBeExported()
-	key.mustBeExported()
-	tt := (*mapType)(unsafe.Pointer(v.typ))
-
-	if (tt.key == stringType || key.kind() == String) && tt.key == key.typ && tt.elem.size <= maxValSize {
-		k := *(*string)(key.ptr)
-		if elem.typ == nil {
-			mapdelete_faststr(v.typ, v.pointer(), k)
-			return
-		}
-		elem.mustBeExported()
-		elem = elem.assignTo("reflect.Value.SetMapIndex", tt.elem, nil)
-		var e unsafe.Pointer
-		if elem.flag&flagIndir != 0 {
-			e = elem.ptr
-		} else {
-			e = unsafe.Pointer(&elem.ptr)
-		}
-		mapassign_faststr(v.typ, v.pointer(), k, e)
-		return
-	}
-
-	key = key.assignTo("reflect.Value.SetMapIndex", tt.key, nil)
-	var k unsafe.Pointer
-	if key.flag&flagIndir != 0 {
-		k = key.ptr
-	} else {
-		k = unsafe.Pointer(&key.ptr)
-	}
-	if elem.typ == nil {
-		mapdelete(v.typ, v.pointer(), k)
-		return
-	}
-	elem.mustBeExported()
-	elem = elem.assignTo("reflect.Value.SetMapIndex", tt.elem, nil)
-	var e unsafe.Pointer
-	if elem.flag&flagIndir != 0 {
-		e = elem.ptr
-	} else {
-		e = unsafe.Pointer(&elem.ptr)
-	}
-	mapassign(v.typ, v.pointer(), k, e)
-}
-
-// SetUint sets v's underlying value to x.
-// It panics if v's Kind is not Uint, Uintptr, Uint8, Uint16, Uint32, or Uint64, or if CanSet() is false.
-func (v Value) SetUint(x uint64) {
-	v.mustBeAssignable()
-	switch k := v.kind(); k {
-	default:
-		panic(&ValueError{"reflect.Value.SetUint", v.kind()})
-	case Uint:
-		*(*uint)(v.ptr) = uint(x)
-	case Uint8:
-		*(*uint8)(v.ptr) = uint8(x)
-	case Uint16:
-		*(*uint16)(v.ptr) = uint16(x)
-	case Uint32:
-		*(*uint32)(v.ptr) = uint32(x)
-	case Uint64:
-		*(*uint64)(v.ptr) = x
-	case Uintptr:
-		*(*uintptr)(v.ptr) = uintptr(x)
-	}
-}
-
-// SetPointer sets the unsafe.Pointer value v to x.
-// It panics if v's Kind is not UnsafePointer.
-func (v Value) SetPointer(x unsafe.Pointer) {
-	v.mustBeAssignable()
-	v.mustBe(UnsafePointer)
-	*(*unsafe.Pointer)(v.ptr) = x
-}
-
-// SetString sets v's underlying value to x.
-// It panics if v's Kind is not String or if CanSet() is false.
-func (v Value) SetString(x string) {
-	v.mustBeAssignable()
-	v.mustBe(String)
-	*(*string)(v.ptr) = x
-}
-
-// Slice returns v[i:j].
-// It panics if v's Kind is not Array, Slice or String, or if v is an unaddressable array,
-// or if the indexes are out of bounds.
-func (v Value) Slice(i, j int) Value {
-	var (
-		cap  int
-		typ  *sliceType
-		base unsafe.Pointer
-	)
-	switch kind := v.kind(); kind {
-	default:
-		panic(&ValueError{"reflect.Value.Slice", v.kind()})
-
-	case Array:
-		if v.flag&flagAddr == 0 {
-			panic("reflect.Value.Slice: slice of unaddressable array")
-		}
-		tt := (*arrayType)(unsafe.Pointer(v.typ))
-		cap = int(tt.len)
-		typ = (*sliceType)(unsafe.Pointer(tt.slice))
-		base = v.ptr
-
-	case Slice:
-		typ = (*sliceType)(unsafe.Pointer(v.typ))
-		s := (*unsafeheader.Slice)(v.ptr)
-		base = s.Data
-		cap = s.Cap
-
-	case String:
-		s := (*unsafeheader.String)(v.ptr)
-		if i < 0 || j < i || j > s.Len {
-			panic("reflect.Value.Slice: string slice index out of bounds")
-		}
-		var t unsafeheader.String
-		if i < s.Len {
-			t = unsafeheader.String{Data: arrayAt(s.Data, i, 1, "i < s.Len"), Len: j - i}
-		}
-		return Value{v.typ, unsafe.Pointer(&t), v.flag}
-	}
-
-	if i < 0 || j < i || j > cap {
-		panic("reflect.Value.Slice: slice index out of bounds")
-	}
-
-	// Declare slice so that gc can see the base pointer in it.
-	var x []unsafe.Pointer
-
-	// Reinterpret as *unsafeheader.Slice to edit.
-	s := (*unsafeheader.Slice)(unsafe.Pointer(&x))
-	s.Len = j - i
-	s.Cap = cap - i
-	if cap-i > 0 {
-		s.Data = arrayAt(base, i, typ.elem.Size(), "i < cap")
-	} else {
-		// do not advance pointer, to avoid pointing beyond end of slice
-		s.Data = base
-	}
-
-	fl := v.flag.ro() | flagIndir | flag(Slice)
-	return Value{typ.common(), unsafe.Pointer(&x), fl}
-}
-
-// Slice3 is the 3-index form of the slice operation: it returns v[i:j:k].
-// It panics if v's Kind is not Array or Slice, or if v is an unaddressable array,
-// or if the indexes are out of bounds.
-func (v Value) Slice3(i, j, k int) Value {
-	var (
-		cap  int
-		typ  *sliceType
-		base unsafe.Pointer
-	)
-	switch kind := v.kind(); kind {
-	default:
-		panic(&ValueError{"reflect.Value.Slice3", v.kind()})
-
-	case Array:
-		if v.flag&flagAddr == 0 {
-			panic("reflect.Value.Slice3: slice of unaddressable array")
-		}
-		tt := (*arrayType)(unsafe.Pointer(v.typ))
-		cap = int(tt.len)
-		typ = (*sliceType)(unsafe.Pointer(tt.slice))
-		base = v.ptr
-
-	case Slice:
-		typ = (*sliceType)(unsafe.Pointer(v.typ))
-		s := (*unsafeheader.Slice)(v.ptr)
-		base = s.Data
-		cap = s.Cap
-	}
-
-	if i < 0 || j < i || k < j || k > cap {
-		panic("reflect.Value.Slice3: slice index out of bounds")
-	}
-
-	// Declare slice so that the garbage collector
-	// can see the base pointer in it.
-	var x []unsafe.Pointer
-
-	// Reinterpret as *unsafeheader.Slice to edit.
-	s := (*unsafeheader.Slice)(unsafe.Pointer(&x))
-	s.Len = j - i
-	s.Cap = k - i
-	if k-i > 0 {
-		s.Data = arrayAt(base, i, typ.elem.Size(), "i < k <= cap")
-	} else {
-		// do not advance pointer, to avoid pointing beyond end of slice
-		s.Data = base
-	}
-
-	fl := v.flag.ro() | flagIndir | flag(Slice)
-	return Value{typ.common(), unsafe.Pointer(&x), fl}
-}
-
-// String returns the string v's underlying value, as a string.
-// String is a special case because of Go's String method convention.
-// Unlike the other getters, it does not panic if v's Kind is not String.
-// Instead, it returns a string of the form "<T value>" where T is v's type.
-// The fmt package treats Values specially. It does not call their String
-// method implicitly but instead prints the concrete values they hold.
-func (v Value) String() string {
-	switch k := v.kind(); k {
-	case Invalid:
-		return "<invalid Value>"
-	case String:
-		return *(*string)(v.ptr)
-	}
-	// If you call String on a reflect.Value of other type, it's better to
-	// print something than to panic. Useful in debugging.
-	return "<" + v.Type().String() + " Value>"
-}
-
-// TryRecv attempts to receive a value from the channel v but will not block.
-// It panics if v's Kind is not Chan.
-// If the receive delivers a value, x is the transferred value and ok is true.
-// If the receive cannot finish without blocking, x is the zero Value and ok is false.
-// If the channel is closed, x is the zero value for the channel's element type and ok is false.
-func (v Value) TryRecv() (x Value, ok bool) {
-	v.mustBe(Chan)
-	v.mustBeExported()
-	return v.recv(true)
-}
-
-// TrySend attempts to send x on the channel v but will not block.
-// It panics if v's Kind is not Chan.
-// It reports whether the value was sent.
-// As in Go, x's value must be assignable to the channel's element type.
-func (v Value) TrySend(x Value) bool {
-	v.mustBe(Chan)
-	v.mustBeExported()
-	return v.send(x, true)
-}
-
-// Type returns v's type.
-func (v Value) Type() Type {
-	f := v.flag
-	if f == 0 {
-		panic(&ValueError{"reflect.Value.Type", Invalid})
-	}
-	if f&flagMethod == 0 {
-		// Easy case
-		return v.typ
-	}
-
-	// Method value.
-	// v.typ describes the receiver, not the method type.
-	i := int(v.flag) >> flagMethodShift
-	if v.typ.Kind() == Interface {
-		// Method on interface.
-		tt := (*interfaceType)(unsafe.Pointer(v.typ))
-		if uint(i) >= uint(len(tt.methods)) {
-			panic("reflect: internal error: invalid method index")
-		}
-		m := &tt.methods[i]
-		return v.typ.typeOff(m.typ)
-	}
-	// Method on concrete type.
-	ms := v.typ.exportedMethods()
-	if uint(i) >= uint(len(ms)) {
-		panic("reflect: internal error: invalid method index")
-	}
-	m := ms[i]
-	return v.typ.typeOff(m.mtyp)
-}
-
-// CanUint reports whether Uint can be used without panicking.
-func (v Value) CanUint() bool {
-	switch v.kind() {
-	case Uint, Uint8, Uint16, Uint32, Uint64, Uintptr:
-		return true
-	default:
-		return false
-	}
-}
-
-// Uint returns v's underlying value, as a uint64.
-// It panics if v's Kind is not Uint, Uintptr, Uint8, Uint16, Uint32, or Uint64.
-func (v Value) Uint() uint64 {
-	k := v.kind()
-	p := v.ptr
-	switch k {
-	case Uint:
-		return uint64(*(*uint)(p))
-	case Uint8:
-		return uint64(*(*uint8)(p))
-	case Uint16:
-		return uint64(*(*uint16)(p))
-	case Uint32:
-		return uint64(*(*uint32)(p))
-	case Uint64:
-		return *(*uint64)(p)
-	case Uintptr:
-		return uint64(*(*uintptr)(p))
-	}
-	panic(&ValueError{"reflect.Value.Uint", v.kind()})
-}
-
-//go:nocheckptr
-// This prevents inlining Value.UnsafeAddr when -d=checkptr is enabled,
-// which ensures cmd/compile can recognize unsafe.Pointer(v.UnsafeAddr())
-// and make an exception.
-
-// UnsafeAddr returns a pointer to v's data, as a uintptr.
-// It is for advanced clients that also import the "unsafe" package.
-// It panics if v is not addressable.
-//
-// It's preferred to use uintptr(Value.Addr().UnsafePointer()) to get the equivalent result.
-func (v Value) UnsafeAddr() uintptr {
-	if v.typ == nil {
-		panic(&ValueError{"reflect.Value.UnsafeAddr", Invalid})
-	}
-	if v.flag&flagAddr == 0 {
-		panic("reflect.Value.UnsafeAddr of unaddressable value")
-	}
-	return uintptr(v.ptr)
-}
-
-// UnsafePointer returns v's value as a unsafe.Pointer.
-// It panics if v's Kind is not Chan, Func, Map, Pointer, Slice, or UnsafePointer.
-//
-// If v's Kind is Func, the returned pointer is an underlying
-// code pointer, but not necessarily enough to identify a
-// single function uniquely. The only guarantee is that the
-// result is zero if and only if v is a nil func Value.
-//
-// If v's Kind is Slice, the returned pointer is to the first
-// element of the slice. If the slice is nil the returned value
-// is nil.  If the slice is empty but non-nil the return value is non-nil.
-func (v Value) UnsafePointer() unsafe.Pointer {
-	k := v.kind()
-	switch k {
-	case Pointer:
-		if v.typ.ptrdata == 0 {
-			// Since it is a not-in-heap pointer, all pointers to the heap are
-			// forbidden! See comment in Value.Elem and issue #48399.
-			if !verifyNotInHeapPtr(*(*uintptr)(v.ptr)) {
-				panic("reflect: reflect.Value.UnsafePointer on an invalid notinheap pointer")
-			}
-			return *(*unsafe.Pointer)(v.ptr)
-		}
-		fallthrough
-	case Chan, Map, UnsafePointer:
-		return v.pointer()
-	case Func:
-		if v.flag&flagMethod != 0 {
-			// As the doc comment says, the returned pointer is an
-			// underlying code pointer but not necessarily enough to
-			// identify a single function uniquely. All method expressions
-			// created via reflect have the same underlying code pointer,
-			// so their Pointers are equal. The function used here must
-			// match the one used in makeMethodValue.
-			code := methodValueCallCodePtr()
-			return *(*unsafe.Pointer)(unsafe.Pointer(&code))
-		}
-		p := v.pointer()
-		// Non-nil func value points at data block.
-		// First word of data block is actual code.
-		if p != nil {
-			p = *(*unsafe.Pointer)(p)
-		}
-		return p
-
-	case Slice:
-		return (*unsafeheader.Slice)(v.ptr).Data
-	}
-	panic(&ValueError{"reflect.Value.UnsafePointer", v.kind()})
-}
-
-// StringHeader is the runtime representation of a string.
-// It cannot be used safely or portably and its representation may
-// change in a later release.
-// Moreover, the Data field is not sufficient to guarantee the data
-// it references will not be garbage collected, so programs must keep
-// a separate, correctly typed pointer to the underlying data.
-type StringHeader struct {
-	Data uintptr
-	Len  int
-}
-
-// SliceHeader is the runtime representation of a slice.
-// It cannot be used safely or portably and its representation may
-// change in a later release.
-// Moreover, the Data field is not sufficient to guarantee the data
-// it references will not be garbage collected, so programs must keep
-// a separate, correctly typed pointer to the underlying data.
-type SliceHeader struct {
-	Data uintptr
-	Len  int
-	Cap  int
-}
-
-func typesMustMatch(what string, t1, t2 Type) {
-	if t1 != t2 {
-		panic(what + ": " + t1.String() + " != " + t2.String())
-	}
-}
-
-// arrayAt returns the i-th element of p,
-// an array whose elements are eltSize bytes wide.
-// The array pointed at by p must have at least i+1 elements:
-// it is invalid (but impossible to check here) to pass i >= len,
-// because then the result will point outside the array.
-// whySafe must explain why i < len. (Passing "i < len" is fine;
-// the benefit is to surface this assumption at the call site.)
-func arrayAt(p unsafe.Pointer, i int, eltSize uintptr, whySafe string) unsafe.Pointer {
-	return add(p, uintptr(i)*eltSize, "i < len")
-}
-
-// grow grows the slice s so that it can hold extra more values, allocating
-// more capacity if needed. It also returns the old and new slice lengths.
-func grow(s Value, extra int) (Value, int, int) {
-	i0 := s.Len()
-	i1 := i0 + extra
-	if i1 < i0 {
-		panic("reflect.Append: slice overflow")
-	}
-	m := s.Cap()
-	if i1 <= m {
-		return s.Slice(0, i1), i0, i1
-	}
-	if m == 0 {
-		m = extra
-	} else {
-		const threshold = 256
-		for m < i1 {
-			if i0 < threshold {
-				m += m
-			} else {
-				m += (m + 3*threshold) / 4
-			}
-		}
-	}
-	t := MakeSlice(s.Type(), i1, m)
-	Copy(t, s)
-	return t, i0, i1
-}
-
-// Append appends the values x to a slice s and returns the resulting slice.
-// As in Go, each x's value must be assignable to the slice's element type.
-func Append(s Value, x ...Value) Value {
-	s.mustBe(Slice)
-	s, i0, i1 := grow(s, len(x))
-	for i, j := i0, 0; i < i1; i, j = i+1, j+1 {
-		s.Index(i).Set(x[j])
-	}
-	return s
-}
-
-// AppendSlice appends a slice t to a slice s and returns the resulting slice.
-// The slices s and t must have the same element type.
-func AppendSlice(s, t Value) Value {
-	s.mustBe(Slice)
-	t.mustBe(Slice)
-	typesMustMatch("reflect.AppendSlice", s.Type().Elem(), t.Type().Elem())
-	s, i0, i1 := grow(s, t.Len())
-	Copy(s.Slice(i0, i1), t)
-	return s
-}
-
-// Copy copies the contents of src into dst until either
-// dst has been filled or src has been exhausted.
-// It returns the number of elements copied.
-// Dst and src each must have kind Slice or Array, and
-// dst and src must have the same element type.
-//
-// As a special case, src can have kind String if the element type of dst is kind Uint8.
-func Copy(dst, src Value) int {
-	dk := dst.kind()
-	if dk != Array && dk != Slice {
-		panic(&ValueError{"reflect.Copy", dk})
-	}
-	if dk == Array {
-		dst.mustBeAssignable()
-	}
-	dst.mustBeExported()
-
-	sk := src.kind()
-	var stringCopy bool
-	if sk != Array && sk != Slice {
-		stringCopy = sk == String && dst.typ.Elem().Kind() == Uint8
-		if !stringCopy {
-			panic(&ValueError{"reflect.Copy", sk})
-		}
-	}
-	src.mustBeExported()
-
-	de := dst.typ.Elem()
-	if !stringCopy {
-		se := src.typ.Elem()
-		typesMustMatch("reflect.Copy", de, se)
-	}
-
-	var ds, ss unsafeheader.Slice
-	if dk == Array {
-		ds.Data = dst.ptr
-		ds.Len = dst.Len()
-		ds.Cap = ds.Len
-	} else {
-		ds = *(*unsafeheader.Slice)(dst.ptr)
-	}
-	if sk == Array {
-		ss.Data = src.ptr
-		ss.Len = src.Len()
-		ss.Cap = ss.Len
-	} else if sk == Slice {
-		ss = *(*unsafeheader.Slice)(src.ptr)
-	} else {
-		sh := *(*unsafeheader.String)(src.ptr)
-		ss.Data = sh.Data
-		ss.Len = sh.Len
-		ss.Cap = sh.Len
-	}
-
-	return typedslicecopy(de.common(), ds, ss)
-}
-
-// A runtimeSelect is a single case passed to rselect.
-// This must match ../runtime/select.go:/runtimeSelect
-type runtimeSelect struct {
-	dir SelectDir      // SelectSend, SelectRecv or SelectDefault
-	typ *rtype         // channel type
-	ch  unsafe.Pointer // channel
-	val unsafe.Pointer // ptr to data (SendDir) or ptr to receive buffer (RecvDir)
-}
-
-// rselect runs a select. It returns the index of the chosen case.
-// If the case was a receive, val is filled in with the received value.
-// The conventional OK bool indicates whether the receive corresponds
-// to a sent value.
-//go:noescape
-func rselect([]runtimeSelect) (chosen int, recvOK bool)
-
-// A SelectDir describes the communication direction of a select case.
-type SelectDir int
-
-// NOTE: These values must match ../runtime/select.go:/selectDir.
-
-const (
-	_             SelectDir = iota
-	SelectSend              // case Chan <- Send
-	SelectRecv              // case <-Chan:
-	SelectDefault           // default
-)
-
-// A SelectCase describes a single case in a select operation.
-// The kind of case depends on Dir, the communication direction.
-//
-// If Dir is SelectDefault, the case represents a default case.
-// Chan and Send must be zero Values.
-//
-// If Dir is SelectSend, the case represents a send operation.
-// Normally Chan's underlying value must be a channel, and Send's underlying value must be
-// assignable to the channel's element type. As a special case, if Chan is a zero Value,
-// then the case is ignored, and the field Send will also be ignored and may be either zero
-// or non-zero.
-//
-// If Dir is SelectRecv, the case represents a receive operation.
-// Normally Chan's underlying value must be a channel and Send must be a zero Value.
-// If Chan is a zero Value, then the case is ignored, but Send must still be a zero Value.
-// When a receive operation is selected, the received Value is returned by Select.
-//
-type SelectCase struct {
-	Dir  SelectDir // direction of case
-	Chan Value     // channel to use (for send or receive)
-	Send Value     // value to send (for send)
-}
-
-// Select executes a select operation described by the list of cases.
-// Like the Go select statement, it blocks until at least one of the cases
-// can proceed, makes a uniform pseudo-random choice,
-// and then executes that case. It returns the index of the chosen case
-// and, if that case was a receive operation, the value received and a
-// boolean indicating whether the value corresponds to a send on the channel
-// (as opposed to a zero value received because the channel is closed).
-// Select supports a maximum of 65536 cases.
-func Select(cases []SelectCase) (chosen int, recv Value, recvOK bool) {
-	if len(cases) > 65536 {
-		panic("reflect.Select: too many cases (max 65536)")
-	}
-	// NOTE: Do not trust that caller is not modifying cases data underfoot.
-	// The range is safe because the caller cannot modify our copy of the len
-	// and each iteration makes its own copy of the value c.
-	var runcases []runtimeSelect
-	if len(cases) > 4 {
-		// Slice is heap allocated due to runtime dependent capacity.
-		runcases = make([]runtimeSelect, len(cases))
-	} else {
-		// Slice can be stack allocated due to constant capacity.
-		runcases = make([]runtimeSelect, len(cases), 4)
-	}
-
-	haveDefault := false
-	for i, c := range cases {
-		rc := &runcases[i]
-		rc.dir = c.Dir
-		switch c.Dir {
-		default:
-			panic("reflect.Select: invalid Dir")
-
-		case SelectDefault: // default
-			if haveDefault {
-				panic("reflect.Select: multiple default cases")
-			}
-			haveDefault = true
-			if c.Chan.IsValid() {
-				panic("reflect.Select: default case has Chan value")
-			}
-			if c.Send.IsValid() {
-				panic("reflect.Select: default case has Send value")
-			}
-
-		case SelectSend:
-			ch := c.Chan
-			if !ch.IsValid() {
-				break
-			}
-			ch.mustBe(Chan)
-			ch.mustBeExported()
-			tt := (*chanType)(unsafe.Pointer(ch.typ))
-			if ChanDir(tt.dir)&SendDir == 0 {
-				panic("reflect.Select: SendDir case using recv-only channel")
-			}
-			rc.ch = ch.pointer()
-			rc.typ = &tt.rtype
-			v := c.Send
-			if !v.IsValid() {
-				panic("reflect.Select: SendDir case missing Send value")
-			}
-			v.mustBeExported()
-			v = v.assignTo("reflect.Select", tt.elem, nil)
-			if v.flag&flagIndir != 0 {
-				rc.val = v.ptr
-			} else {
-				rc.val = unsafe.Pointer(&v.ptr)
-			}
-
-		case SelectRecv:
-			if c.Send.IsValid() {
-				panic("reflect.Select: RecvDir case has Send value")
-			}
-			ch := c.Chan
-			if !ch.IsValid() {
-				break
-			}
-			ch.mustBe(Chan)
-			ch.mustBeExported()
-			tt := (*chanType)(unsafe.Pointer(ch.typ))
-			if ChanDir(tt.dir)&RecvDir == 0 {
-				panic("reflect.Select: RecvDir case using send-only channel")
-			}
-			rc.ch = ch.pointer()
-			rc.typ = &tt.rtype
-			rc.val = unsafe_New(tt.elem)
-		}
-	}
-
-	chosen, recvOK = rselect(runcases)
-	if runcases[chosen].dir == SelectRecv {
-		tt := (*chanType)(unsafe.Pointer(runcases[chosen].typ))
-		t := tt.elem
-		p := runcases[chosen].val
-		fl := flag(t.Kind())
-		if ifaceIndir(t) {
-			recv = Value{t, p, fl | flagIndir}
-		} else {
-			recv = Value{t, *(*unsafe.Pointer)(p), fl}
-		}
-	}
-	return chosen, recv, recvOK
-}
-
-/*
- * constructors
- */
-
-// implemented in package runtime
-func unsafe_New(*rtype) unsafe.Pointer
-func unsafe_NewArray(*rtype, int) unsafe.Pointer
-
-// MakeSlice creates a new zero-initialized slice value
-// for the specified slice type, length, and capacity.
-func MakeSlice(typ Type, len, cap int) Value {
-	if typ.Kind() != Slice {
-		panic("reflect.MakeSlice of non-slice type")
-	}
-	if len < 0 {
-		panic("reflect.MakeSlice: negative len")
-	}
-	if cap < 0 {
-		panic("reflect.MakeSlice: negative cap")
-	}
-	if len > cap {
-		panic("reflect.MakeSlice: len > cap")
-	}
-
-	s := unsafeheader.Slice{Data: unsafe_NewArray(typ.Elem().(*rtype), cap), Len: len, Cap: cap}
-	return Value{typ.(*rtype), unsafe.Pointer(&s), flagIndir | flag(Slice)}
-}
-
-// MakeChan creates a new channel with the specified type and buffer size.
-func MakeChan(typ Type, buffer int) Value {
-	if typ.Kind() != Chan {
-		panic("reflect.MakeChan of non-chan type")
-	}
-	if buffer < 0 {
-		panic("reflect.MakeChan: negative buffer size")
-	}
-	if typ.ChanDir() != BothDir {
-		panic("reflect.MakeChan: unidirectional channel type")
-	}
-	t := typ.(*rtype)
-	ch := makechan(t, buffer)
-	return Value{t, ch, flag(Chan)}
-}
-
-// MakeMap creates a new map with the specified type.
-func MakeMap(typ Type) Value {
-	return MakeMapWithSize(typ, 0)
-}
-
-// MakeMapWithSize creates a new map with the specified type
-// and initial space for approximately n elements.
-func MakeMapWithSize(typ Type, n int) Value {
-	if typ.Kind() != Map {
-		panic("reflect.MakeMapWithSize of non-map type")
-	}
-	t := typ.(*rtype)
-	m := makemap(t, n)
-	return Value{t, m, flag(Map)}
-}
-
-// Indirect returns the value that v points to.
-// If v is a nil pointer, Indirect returns a zero Value.
-// If v is not a pointer, Indirect returns v.
-func Indirect(v Value) Value {
-	if v.Kind() != Pointer {
-		return v
-	}
-	return v.Elem()
-}
-
-// ValueOf returns a new Value initialized to the concrete value
-// stored in the interface i. ValueOf(nil) returns the zero Value.
-func ValueOf(i any) Value {
-	if i == nil {
-		return Value{}
-	}
-
-	// TODO: Maybe allow contents of a Value to live on the stack.
-	// For now we make the contents always escape to the heap. It
-	// makes life easier in a few places (see chanrecv/mapassign
-	// comment below).
-	escapes(i)
-
-	return unpackEface(i)
-}
-
-// Zero returns a Value representing the zero value for the specified type.
-// The result is different from the zero value of the Value struct,
-// which represents no value at all.
-// For example, Zero(TypeOf(42)) returns a Value with Kind Int and value 0.
-// The returned value is neither addressable nor settable.
-func Zero(typ Type) Value {
-	if typ == nil {
-		panic("reflect: Zero(nil)")
-	}
-	t := typ.(*rtype)
-	fl := flag(t.Kind())
-	if ifaceIndir(t) {
-		var p unsafe.Pointer
-		if t.size <= maxZero {
-			p = unsafe.Pointer(&zeroVal[0])
-		} else {
-			p = unsafe_New(t)
-		}
-		return Value{t, p, fl | flagIndir}
-	}
-	return Value{t, nil, fl}
-}
-
-// must match declarations in runtime/map.go.
-const maxZero = 1024
-
-//go:linkname zeroVal runtime.zeroVal
-var zeroVal [maxZero]byte
-
-// New returns a Value representing a pointer to a new zero value
-// for the specified type. That is, the returned Value's Type is PointerTo(typ).
-func New(typ Type) Value {
-	if typ == nil {
-		panic("reflect: New(nil)")
-	}
-	t := typ.(*rtype)
-	pt := t.ptrTo()
-	if ifaceIndir(pt) {
-		// This is a pointer to a go:notinheap type.
-		panic("reflect: New of type that may not be allocated in heap (possibly undefined cgo C type)")
-	}
-	ptr := unsafe_New(t)
-	fl := flag(Pointer)
-	return Value{pt, ptr, fl}
-}
-
-// NewAt returns a Value representing a pointer to a value of the
-// specified type, using p as that pointer.
-func NewAt(typ Type, p unsafe.Pointer) Value {
-	fl := flag(Pointer)
-	t := typ.(*rtype)
-	return Value{t.ptrTo(), p, fl}
-}
-
-// assignTo returns a value v that can be assigned directly to typ.
-// It panics if v is not assignable to typ.
-// For a conversion to an interface type, target is a suggested scratch space to use.
-// target must be initialized memory (or nil).
-func (v Value) assignTo(context string, dst *rtype, target unsafe.Pointer) Value {
-	if v.flag&flagMethod != 0 {
-		v = makeMethodValue(context, v)
-	}
-
-	switch {
-	case directlyAssignable(dst, v.typ):
-		// Overwrite type so that they match.
-		// Same memory layout, so no harm done.
-		fl := v.flag&(flagAddr|flagIndir) | v.flag.ro()
-		fl |= flag(dst.Kind())
-		return Value{dst, v.ptr, fl}
-
-	case implements(dst, v.typ):
-		if target == nil {
-			target = unsafe_New(dst)
-		}
-		if v.Kind() == Interface && v.IsNil() {
-			// A nil ReadWriter passed to nil Reader is OK,
-			// but using ifaceE2I below will panic.
-			// Avoid the panic by returning a nil dst (e.g., Reader) explicitly.
-			return Value{dst, nil, flag(Interface)}
-		}
-		x := valueInterface(v, false)
-		if dst.NumMethod() == 0 {
-			*(*any)(target) = x
-		} else {
-			ifaceE2I(dst, x, target)
-		}
-		return Value{dst, target, flagIndir | flag(Interface)}
-	}
-
-	// Failed.
-	panic(context + ": value of type " + v.typ.String() + " is not assignable to type " + dst.String())
-}
-
-// Convert returns the value v converted to type t.
-// If the usual Go conversion rules do not allow conversion
-// of the value v to type t, or if converting v to type t panics, Convert panics.
-func (v Value) Convert(t Type) Value {
-	if v.flag&flagMethod != 0 {
-		v = makeMethodValue("Convert", v)
-	}
-	op := convertOp(t.common(), v.typ)
-	if op == nil {
-		panic("reflect.Value.Convert: value of type " + v.typ.String() + " cannot be converted to type " + t.String())
-	}
-	return op(v, t)
-}
-
-// CanConvert reports whether the value v can be converted to type t.
-// If v.CanConvert(t) returns true then v.Convert(t) will not panic.
-func (v Value) CanConvert(t Type) bool {
-	vt := v.Type()
-	if !vt.ConvertibleTo(t) {
-		return false
-	}
-	// Currently the only conversion that is OK in terms of type
-	// but that can panic depending on the value is converting
-	// from slice to pointer-to-array.
-	if vt.Kind() == Slice && t.Kind() == Pointer && t.Elem().Kind() == Array {
-		n := t.Elem().Len()
-		if n > v.Len() {
-			return false
-		}
-	}
-	return true
-}
-
-// convertOp returns the function to convert a value of type src
-// to a value of type dst. If the conversion is illegal, convertOp returns nil.
-func convertOp(dst, src *rtype) func(Value, Type) Value {
-	switch src.Kind() {
-	case Int, Int8, Int16, Int32, Int64:
-		switch dst.Kind() {
-		case Int, Int8, Int16, Int32, Int64, Uint, Uint8, Uint16, Uint32, Uint64, Uintptr:
-			return cvtInt
-		case Float32, Float64:
-			return cvtIntFloat
-		case String:
-			return cvtIntString
-		}
-
-	case Uint, Uint8, Uint16, Uint32, Uint64, Uintptr:
-		switch dst.Kind() {
-		case Int, Int8, Int16, Int32, Int64, Uint, Uint8, Uint16, Uint32, Uint64, Uintptr:
-			return cvtUint
-		case Float32, Float64:
-			return cvtUintFloat
-		case String:
-			return cvtUintString
-		}
-
-	case Float32, Float64:
-		switch dst.Kind() {
-		case Int, Int8, Int16, Int32, Int64:
-			return cvtFloatInt
-		case Uint, Uint8, Uint16, Uint32, Uint64, Uintptr:
-			return cvtFloatUint
-		case Float32, Float64:
-			return cvtFloat
-		}
-
-	case Complex64, Complex128:
-		switch dst.Kind() {
-		case Complex64, Complex128:
-			return cvtComplex
-		}
-
-	case String:
-		if dst.Kind() == Slice && dst.Elem().PkgPath() == "" {
-			switch dst.Elem().Kind() {
-			case Uint8:
-				return cvtStringBytes
-			case Int32:
-				return cvtStringRunes
-			}
-		}
-
-	case Slice:
-		if dst.Kind() == String && src.Elem().PkgPath() == "" {
-			switch src.Elem().Kind() {
-			case Uint8:
-				return cvtBytesString
-			case Int32:
-				return cvtRunesString
-			}
-		}
-		// "x is a slice, T is a pointer-to-array type,
-		// and the slice and array types have identical element types."
-		if dst.Kind() == Pointer && dst.Elem().Kind() == Array && src.Elem() == dst.Elem().Elem() {
-			return cvtSliceArrayPtr
-		}
-
-	case Chan:
-		if dst.Kind() == Chan && specialChannelAssignability(dst, src) {
-			return cvtDirect
-		}
-	}
-
-	// dst and src have same underlying type.
-	if haveIdenticalUnderlyingType(dst, src, false) {
-		return cvtDirect
-	}
-
-	// dst and src are non-defined pointer types with same underlying base type.
-	if dst.Kind() == Pointer && dst.Name() == "" &&
-		src.Kind() == Pointer && src.Name() == "" &&
-		haveIdenticalUnderlyingType(dst.Elem().common(), src.Elem().common(), false) {
-		return cvtDirect
-	}
-
-	if implements(dst, src) {
-		if src.Kind() == Interface {
-			return cvtI2I
-		}
-		return cvtT2I
-	}
-
-	return nil
-}
-
-// makeInt returns a Value of type t equal to bits (possibly truncated),
-// where t is a signed or unsigned int type.
-func makeInt(f flag, bits uint64, t Type) Value {
-	typ := t.common()
-	ptr := unsafe_New(typ)
-	switch typ.size {
-	case 1:
-		*(*uint8)(ptr) = uint8(bits)
-	case 2:
-		*(*uint16)(ptr) = uint16(bits)
-	case 4:
-		*(*uint32)(ptr) = uint32(bits)
-	case 8:
-		*(*uint64)(ptr) = bits
-	}
-	return Value{typ, ptr, f | flagIndir | flag(typ.Kind())}
-}
-
-// makeFloat returns a Value of type t equal to v (possibly truncated to float32),
-// where t is a float32 or float64 type.
-func makeFloat(f flag, v float64, t Type) Value {
-	typ := t.common()
-	ptr := unsafe_New(typ)
-	switch typ.size {
-	case 4:
-		*(*float32)(ptr) = float32(v)
-	case 8:
-		*(*float64)(ptr) = v
-	}
-	return Value{typ, ptr, f | flagIndir | flag(typ.Kind())}
-}
-
-// makeFloat returns a Value of type t equal to v, where t is a float32 type.
-func makeFloat32(f flag, v float32, t Type) Value {
-	typ := t.common()
-	ptr := unsafe_New(typ)
-	*(*float32)(ptr) = v
-	return Value{typ, ptr, f | flagIndir | flag(typ.Kind())}
-}
-
-// makeComplex returns a Value of type t equal to v (possibly truncated to complex64),
-// where t is a complex64 or complex128 type.
-func makeComplex(f flag, v complex128, t Type) Value {
-	typ := t.common()
-	ptr := unsafe_New(typ)
-	switch typ.size {
-	case 8:
-		*(*complex64)(ptr) = complex64(v)
-	case 16:
-		*(*complex128)(ptr) = v
-	}
-	return Value{typ, ptr, f | flagIndir | flag(typ.Kind())}
-}
-
-func makeString(f flag, v string, t Type) Value {
-	ret := New(t).Elem()
-	ret.SetString(v)
-	ret.flag = ret.flag&^flagAddr | f
-	return ret
-}
-
-func makeBytes(f flag, v []byte, t Type) Value {
-	ret := New(t).Elem()
-	ret.SetBytes(v)
-	ret.flag = ret.flag&^flagAddr | f
-	return ret
-}
-
-func makeRunes(f flag, v []rune, t Type) Value {
-	ret := New(t).Elem()
-	ret.setRunes(v)
-	ret.flag = ret.flag&^flagAddr | f
-	return ret
-}
-
-// These conversion functions are returned by convertOp
-// for classes of conversions. For example, the first function, cvtInt,
-// takes any value v of signed int type and returns the value converted
-// to type t, where t is any signed or unsigned int type.
-
-// convertOp: intXX -> [u]intXX
-func cvtInt(v Value, t Type) Value {
-	return makeInt(v.flag.ro(), uint64(v.Int()), t)
-}
-
-// convertOp: uintXX -> [u]intXX
-func cvtUint(v Value, t Type) Value {
-	return makeInt(v.flag.ro(), v.Uint(), t)
-}
-
-// convertOp: floatXX -> intXX
-func cvtFloatInt(v Value, t Type) Value {
-	return makeInt(v.flag.ro(), uint64(int64(v.Float())), t)
-}
-
-// convertOp: floatXX -> uintXX
-func cvtFloatUint(v Value, t Type) Value {
-	return makeInt(v.flag.ro(), uint64(v.Float()), t)
-}
-
-// convertOp: intXX -> floatXX
-func cvtIntFloat(v Value, t Type) Value {
-	return makeFloat(v.flag.ro(), float64(v.Int()), t)
-}
-
-// convertOp: uintXX -> floatXX
-func cvtUintFloat(v Value, t Type) Value {
-	return makeFloat(v.flag.ro(), float64(v.Uint()), t)
-}
-
-// convertOp: floatXX -> floatXX
-func cvtFloat(v Value, t Type) Value {
-	if v.Type().Kind() == Float32 && t.Kind() == Float32 {
-		// Don't do any conversion if both types have underlying type float32.
-		// This avoids converting to float64 and back, which will
-		// convert a signaling NaN to a quiet NaN. See issue 36400.
-		return makeFloat32(v.flag.ro(), *(*float32)(v.ptr), t)
-	}
-	return makeFloat(v.flag.ro(), v.Float(), t)
-}
-
-// convertOp: complexXX -> complexXX
-func cvtComplex(v Value, t Type) Value {
-	return makeComplex(v.flag.ro(), v.Complex(), t)
-}
-
-// convertOp: intXX -> string
-func cvtIntString(v Value, t Type) Value {
-	s := "\uFFFD"
-	if x := v.Int(); int64(rune(x)) == x {
-		s = string(rune(x))
-	}
-	return makeString(v.flag.ro(), s, t)
-}
-
-// convertOp: uintXX -> string
-func cvtUintString(v Value, t Type) Value {
-	s := "\uFFFD"
-	if x := v.Uint(); uint64(rune(x)) == x {
-		s = string(rune(x))
-	}
-	return makeString(v.flag.ro(), s, t)
-}
-
-// convertOp: []byte -> string
-func cvtBytesString(v Value, t Type) Value {
-	return makeString(v.flag.ro(), string(v.Bytes()), t)
-}
-
-// convertOp: string -> []byte
-func cvtStringBytes(v Value, t Type) Value {
-	return makeBytes(v.flag.ro(), []byte(v.String()), t)
-}
-
-// convertOp: []rune -> string
-func cvtRunesString(v Value, t Type) Value {
-	return makeString(v.flag.ro(), string(v.runes()), t)
-}
-
-// convertOp: string -> []rune
-func cvtStringRunes(v Value, t Type) Value {
-	return makeRunes(v.flag.ro(), []rune(v.String()), t)
-}
-
-// convertOp: []T -> *[N]T
-func cvtSliceArrayPtr(v Value, t Type) Value {
-	n := t.Elem().Len()
-	if n > v.Len() {
-		panic("reflect: cannot convert slice with length " + itoa.Itoa(v.Len()) + " to pointer to array with length " + itoa.Itoa(n))
-	}
-	h := (*unsafeheader.Slice)(v.ptr)
-	return Value{t.common(), h.Data, v.flag&^(flagIndir|flagAddr|flagKindMask) | flag(Pointer)}
-}
-
-// convertOp: direct copy
-func cvtDirect(v Value, typ Type) Value {
-	f := v.flag
-	t := typ.common()
-	ptr := v.ptr
-	if f&flagAddr != 0 {
-		// indirect, mutable word - make a copy
-		c := unsafe_New(t)
-		typedmemmove(t, c, ptr)
-		ptr = c
-		f &^= flagAddr
-	}
-	return Value{t, ptr, v.flag.ro() | f} // v.flag.ro()|f == f?
-}
-
-// convertOp: concrete -> interface
-func cvtT2I(v Value, typ Type) Value {
-	target := unsafe_New(typ.common())
-	x := valueInterface(v, false)
-	if typ.NumMethod() == 0 {
-		*(*any)(target) = x
-	} else {
-		ifaceE2I(typ.(*rtype), x, target)
-	}
-	return Value{typ.common(), target, v.flag.ro() | flagIndir | flag(Interface)}
-}
-
-// convertOp: interface -> interface
-func cvtI2I(v Value, typ Type) Value {
-	if v.IsNil() {
-		ret := Zero(typ)
-		ret.flag |= v.flag.ro()
-		return ret
-	}
-	return cvtT2I(v.Elem(), typ)
-}
-
-// implemented in ../runtime
-func chancap(ch unsafe.Pointer) int
-func chanclose(ch unsafe.Pointer)
-func chanlen(ch unsafe.Pointer) int
-
-// Note: some of the noescape annotations below are technically a lie,
-// but safe in the context of this package. Functions like chansend
-// and mapassign don't escape the referent, but may escape anything
-// the referent points to (they do shallow copies of the referent).
-// It is safe in this package because the referent may only point
-// to something a Value may point to, and that is always in the heap
-// (due to the escapes() call in ValueOf).
-
-//go:noescape
-func chanrecv(ch unsafe.Pointer, nb bool, val unsafe.Pointer) (selected, received bool)
-
-//go:noescape
-func chansend(ch unsafe.Pointer, val unsafe.Pointer, nb bool) bool
-
-func makechan(typ *rtype, size int) (ch unsafe.Pointer)
-func makemap(t *rtype, cap int) (m unsafe.Pointer)
-
-//go:noescape
-func mapaccess(t *rtype, m unsafe.Pointer, key unsafe.Pointer) (val unsafe.Pointer)
-
-//go:noescape
-func mapaccess_faststr(t *rtype, m unsafe.Pointer, key string) (val unsafe.Pointer)
-
-//go:noescape
-func mapassign(t *rtype, m unsafe.Pointer, key, val unsafe.Pointer)
-
-//go:noescape
-func mapassign_faststr(t *rtype, m unsafe.Pointer, key string, val unsafe.Pointer)
-
-//go:noescape
-func mapdelete(t *rtype, m unsafe.Pointer, key unsafe.Pointer)
-
-//go:noescape
-func mapdelete_faststr(t *rtype, m unsafe.Pointer, key string)
-
-//go:noescape
-func mapiterinit(t *rtype, m unsafe.Pointer, it *hiter)
-
-//go:noescape
-func mapiterkey(it *hiter) (key unsafe.Pointer)
-
-//go:noescape
-func mapiterelem(it *hiter) (elem unsafe.Pointer)
-
-//go:noescape
-func mapiternext(it *hiter)
-
-//go:noescape
-func maplen(m unsafe.Pointer) int
-
-// call calls fn with "stackArgsSize" bytes of stack arguments laid out
-// at stackArgs and register arguments laid out in regArgs. frameSize is
-// the total amount of stack space that will be reserved by call, so this
-// should include enough space to spill register arguments to the stack in
-// case of preemption.
-//
-// After fn returns, call copies stackArgsSize-stackRetOffset result bytes
-// back into stackArgs+stackRetOffset before returning, for any return
-// values passed on the stack. Register-based return values will be found
-// in the same regArgs structure.
-//
-// regArgs must also be prepared with an appropriate ReturnIsPtr bitmap
-// indicating which registers will contain pointer-valued return values. The
-// purpose of this bitmap is to keep pointers visible to the GC between
-// returning from reflectcall and actually using them.
-//
-// If copying result bytes back from the stack, the caller must pass the
-// argument frame type as stackArgsType, so that call can execute appropriate
-// write barriers during the copy.
-//
-// Arguments passed through to call do not escape. The type is used only in a
-// very limited callee of call, the stackArgs are copied, and regArgs is only
-// used in the call frame.
-//go:noescape
-//go:linkname call runtime.reflectcall
-func call(stackArgsType *rtype, f, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-
-func ifaceE2I(t *rtype, src any, dst unsafe.Pointer)
-
-// memmove copies size bytes to dst from src. No write barriers are used.
-//go:noescape
-func memmove(dst, src unsafe.Pointer, size uintptr)
-
-// typedmemmove copies a value of type t to dst from src.
-//go:noescape
-func typedmemmove(t *rtype, dst, src unsafe.Pointer)
-
-// typedmemmovepartial is like typedmemmove but assumes that
-// dst and src point off bytes into the value and only copies size bytes.
-//go:noescape
-func typedmemmovepartial(t *rtype, dst, src unsafe.Pointer, off, size uintptr)
-
-// typedmemclr zeros the value at ptr of type t.
-//go:noescape
-func typedmemclr(t *rtype, ptr unsafe.Pointer)
-
-// typedmemclrpartial is like typedmemclr but assumes that
-// dst points off bytes into the value and only clears size bytes.
-//go:noescape
-func typedmemclrpartial(t *rtype, ptr unsafe.Pointer, off, size uintptr)
-
-// typedslicecopy copies a slice of elemType values from src to dst,
-// returning the number of elements copied.
-//go:noescape
-func typedslicecopy(elemType *rtype, dst, src unsafeheader.Slice) int
-
-//go:noescape
-func typehash(t *rtype, p unsafe.Pointer, h uintptr) uintptr
-
-func verifyNotInHeapPtr(p uintptr) bool
-
-// Dummy annotation marking that the value x escapes,
-// for use in cases where the reflect code is so clever that
-// the compiler cannot follow.
-func escapes(x any) {
-	if dummy.b {
-		dummy.x = x
-	}
-}
-
-var dummy struct {
-	b bool
-	x any
-}
diff --git a/contrib/go/_std_1.18/src/runtime/alg.go b/contrib/go/_std_1.18/src/runtime/alg.go
deleted file mode 100644
index 5d7d1c77f4..0000000000
--- a/contrib/go/_std_1.18/src/runtime/alg.go
+++ /dev/null
@@ -1,353 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"internal/cpu"
-	"internal/goarch"
-	"unsafe"
-)
-
-const (
-	c0 = uintptr((8-goarch.PtrSize)/4*2860486313 + (goarch.PtrSize-4)/4*33054211828000289)
-	c1 = uintptr((8-goarch.PtrSize)/4*3267000013 + (goarch.PtrSize-4)/4*23344194077549503)
-)
-
-func memhash0(p unsafe.Pointer, h uintptr) uintptr {
-	return h
-}
-
-func memhash8(p unsafe.Pointer, h uintptr) uintptr {
-	return memhash(p, h, 1)
-}
-
-func memhash16(p unsafe.Pointer, h uintptr) uintptr {
-	return memhash(p, h, 2)
-}
-
-func memhash128(p unsafe.Pointer, h uintptr) uintptr {
-	return memhash(p, h, 16)
-}
-
-//go:nosplit
-func memhash_varlen(p unsafe.Pointer, h uintptr) uintptr {
-	ptr := getclosureptr()
-	size := *(*uintptr)(unsafe.Pointer(ptr + unsafe.Sizeof(h)))
-	return memhash(p, h, size)
-}
-
-// runtime variable to check if the processor we're running on
-// actually supports the instructions used by the AES-based
-// hash implementation.
-var useAeshash bool
-
-// in asm_*.s
-func memhash(p unsafe.Pointer, h, s uintptr) uintptr
-func memhash32(p unsafe.Pointer, h uintptr) uintptr
-func memhash64(p unsafe.Pointer, h uintptr) uintptr
-func strhash(p unsafe.Pointer, h uintptr) uintptr
-
-func strhashFallback(a unsafe.Pointer, h uintptr) uintptr {
-	x := (*stringStruct)(a)
-	return memhashFallback(x.str, h, uintptr(x.len))
-}
-
-// NOTE: Because NaN != NaN, a map can contain any
-// number of (mostly useless) entries keyed with NaNs.
-// To avoid long hash chains, we assign a random number
-// as the hash value for a NaN.
-
-func f32hash(p unsafe.Pointer, h uintptr) uintptr {
-	f := *(*float32)(p)
-	switch {
-	case f == 0:
-		return c1 * (c0 ^ h) // +0, -0
-	case f != f:
-		return c1 * (c0 ^ h ^ uintptr(fastrand())) // any kind of NaN
-	default:
-		return memhash(p, h, 4)
-	}
-}
-
-func f64hash(p unsafe.Pointer, h uintptr) uintptr {
-	f := *(*float64)(p)
-	switch {
-	case f == 0:
-		return c1 * (c0 ^ h) // +0, -0
-	case f != f:
-		return c1 * (c0 ^ h ^ uintptr(fastrand())) // any kind of NaN
-	default:
-		return memhash(p, h, 8)
-	}
-}
-
-func c64hash(p unsafe.Pointer, h uintptr) uintptr {
-	x := (*[2]float32)(p)
-	return f32hash(unsafe.Pointer(&x[1]), f32hash(unsafe.Pointer(&x[0]), h))
-}
-
-func c128hash(p unsafe.Pointer, h uintptr) uintptr {
-	x := (*[2]float64)(p)
-	return f64hash(unsafe.Pointer(&x[1]), f64hash(unsafe.Pointer(&x[0]), h))
-}
-
-func interhash(p unsafe.Pointer, h uintptr) uintptr {
-	a := (*iface)(p)
-	tab := a.tab
-	if tab == nil {
-		return h
-	}
-	t := tab._type
-	if t.equal == nil {
-		// Check hashability here. We could do this check inside
-		// typehash, but we want to report the topmost type in
-		// the error text (e.g. in a struct with a field of slice type
-		// we want to report the struct, not the slice).
-		panic(errorString("hash of unhashable type " + t.string()))
-	}
-	if isDirectIface(t) {
-		return c1 * typehash(t, unsafe.Pointer(&a.data), h^c0)
-	} else {
-		return c1 * typehash(t, a.data, h^c0)
-	}
-}
-
-func nilinterhash(p unsafe.Pointer, h uintptr) uintptr {
-	a := (*eface)(p)
-	t := a._type
-	if t == nil {
-		return h
-	}
-	if t.equal == nil {
-		// See comment in interhash above.
-		panic(errorString("hash of unhashable type " + t.string()))
-	}
-	if isDirectIface(t) {
-		return c1 * typehash(t, unsafe.Pointer(&a.data), h^c0)
-	} else {
-		return c1 * typehash(t, a.data, h^c0)
-	}
-}
-
-// typehash computes the hash of the object of type t at address p.
-// h is the seed.
-// This function is seldom used. Most maps use for hashing either
-// fixed functions (e.g. f32hash) or compiler-generated functions
-// (e.g. for a type like struct { x, y string }). This implementation
-// is slower but more general and is used for hashing interface types
-// (called from interhash or nilinterhash, above) or for hashing in
-// maps generated by reflect.MapOf (reflect_typehash, below).
-// Note: this function must match the compiler generated
-// functions exactly. See issue 37716.
-func typehash(t *_type, p unsafe.Pointer, h uintptr) uintptr {
-	if t.tflag&tflagRegularMemory != 0 {
-		// Handle ptr sizes specially, see issue 37086.
-		switch t.size {
-		case 4:
-			return memhash32(p, h)
-		case 8:
-			return memhash64(p, h)
-		default:
-			return memhash(p, h, t.size)
-		}
-	}
-	switch t.kind & kindMask {
-	case kindFloat32:
-		return f32hash(p, h)
-	case kindFloat64:
-		return f64hash(p, h)
-	case kindComplex64:
-		return c64hash(p, h)
-	case kindComplex128:
-		return c128hash(p, h)
-	case kindString:
-		return strhash(p, h)
-	case kindInterface:
-		i := (*interfacetype)(unsafe.Pointer(t))
-		if len(i.mhdr) == 0 {
-			return nilinterhash(p, h)
-		}
-		return interhash(p, h)
-	case kindArray:
-		a := (*arraytype)(unsafe.Pointer(t))
-		for i := uintptr(0); i < a.len; i++ {
-			h = typehash(a.elem, add(p, i*a.elem.size), h)
-		}
-		return h
-	case kindStruct:
-		s := (*structtype)(unsafe.Pointer(t))
-		for _, f := range s.fields {
-			if f.name.isBlank() {
-				continue
-			}
-			h = typehash(f.typ, add(p, f.offset()), h)
-		}
-		return h
-	default:
-		// Should never happen, as typehash should only be called
-		// with comparable types.
-		panic(errorString("hash of unhashable type " + t.string()))
-	}
-}
-
-//go:linkname reflect_typehash reflect.typehash
-func reflect_typehash(t *_type, p unsafe.Pointer, h uintptr) uintptr {
-	return typehash(t, p, h)
-}
-
-func memequal0(p, q unsafe.Pointer) bool {
-	return true
-}
-func memequal8(p, q unsafe.Pointer) bool {
-	return *(*int8)(p) == *(*int8)(q)
-}
-func memequal16(p, q unsafe.Pointer) bool {
-	return *(*int16)(p) == *(*int16)(q)
-}
-func memequal32(p, q unsafe.Pointer) bool {
-	return *(*int32)(p) == *(*int32)(q)
-}
-func memequal64(p, q unsafe.Pointer) bool {
-	return *(*int64)(p) == *(*int64)(q)
-}
-func memequal128(p, q unsafe.Pointer) bool {
-	return *(*[2]int64)(p) == *(*[2]int64)(q)
-}
-func f32equal(p, q unsafe.Pointer) bool {
-	return *(*float32)(p) == *(*float32)(q)
-}
-func f64equal(p, q unsafe.Pointer) bool {
-	return *(*float64)(p) == *(*float64)(q)
-}
-func c64equal(p, q unsafe.Pointer) bool {
-	return *(*complex64)(p) == *(*complex64)(q)
-}
-func c128equal(p, q unsafe.Pointer) bool {
-	return *(*complex128)(p) == *(*complex128)(q)
-}
-func strequal(p, q unsafe.Pointer) bool {
-	return *(*string)(p) == *(*string)(q)
-}
-func interequal(p, q unsafe.Pointer) bool {
-	x := *(*iface)(p)
-	y := *(*iface)(q)
-	return x.tab == y.tab && ifaceeq(x.tab, x.data, y.data)
-}
-func nilinterequal(p, q unsafe.Pointer) bool {
-	x := *(*eface)(p)
-	y := *(*eface)(q)
-	return x._type == y._type && efaceeq(x._type, x.data, y.data)
-}
-func efaceeq(t *_type, x, y unsafe.Pointer) bool {
-	if t == nil {
-		return true
-	}
-	eq := t.equal
-	if eq == nil {
-		panic(errorString("comparing uncomparable type " + t.string()))
-	}
-	if isDirectIface(t) {
-		// Direct interface types are ptr, chan, map, func, and single-element structs/arrays thereof.
-		// Maps and funcs are not comparable, so they can't reach here.
-		// Ptrs, chans, and single-element items can be compared directly using ==.
-		return x == y
-	}
-	return eq(x, y)
-}
-func ifaceeq(tab *itab, x, y unsafe.Pointer) bool {
-	if tab == nil {
-		return true
-	}
-	t := tab._type
-	eq := t.equal
-	if eq == nil {
-		panic(errorString("comparing uncomparable type " + t.string()))
-	}
-	if isDirectIface(t) {
-		// See comment in efaceeq.
-		return x == y
-	}
-	return eq(x, y)
-}
-
-// Testing adapters for hash quality tests (see hash_test.go)
-func stringHash(s string, seed uintptr) uintptr {
-	return strhash(noescape(unsafe.Pointer(&s)), seed)
-}
-
-func bytesHash(b []byte, seed uintptr) uintptr {
-	s := (*slice)(unsafe.Pointer(&b))
-	return memhash(s.array, seed, uintptr(s.len))
-}
-
-func int32Hash(i uint32, seed uintptr) uintptr {
-	return memhash32(noescape(unsafe.Pointer(&i)), seed)
-}
-
-func int64Hash(i uint64, seed uintptr) uintptr {
-	return memhash64(noescape(unsafe.Pointer(&i)), seed)
-}
-
-func efaceHash(i any, seed uintptr) uintptr {
-	return nilinterhash(noescape(unsafe.Pointer(&i)), seed)
-}
-
-func ifaceHash(i interface {
-	F()
-}, seed uintptr) uintptr {
-	return interhash(noescape(unsafe.Pointer(&i)), seed)
-}
-
-const hashRandomBytes = goarch.PtrSize / 4 * 64
-
-// used in asm_{386,amd64,arm64}.s to seed the hash function
-var aeskeysched [hashRandomBytes]byte
-
-// used in hash{32,64}.go to seed the hash function
-var hashkey [4]uintptr
-
-func alginit() {
-	// Install AES hash algorithms if the instructions needed are present.
-	if (GOARCH == "386" || GOARCH == "amd64") &&
-		cpu.X86.HasAES && // AESENC
-		cpu.X86.HasSSSE3 && // PSHUFB
-		cpu.X86.HasSSE41 { // PINSR{D,Q}
-		initAlgAES()
-		return
-	}
-	if GOARCH == "arm64" && cpu.ARM64.HasAES {
-		initAlgAES()
-		return
-	}
-	getRandomData((*[len(hashkey) * goarch.PtrSize]byte)(unsafe.Pointer(&hashkey))[:])
-	hashkey[0] |= 1 // make sure these numbers are odd
-	hashkey[1] |= 1
-	hashkey[2] |= 1
-	hashkey[3] |= 1
-}
-
-func initAlgAES() {
-	useAeshash = true
-	// Initialize with random data so hash collisions will be hard to engineer.
-	getRandomData(aeskeysched[:])
-}
-
-// Note: These routines perform the read with a native endianness.
-func readUnaligned32(p unsafe.Pointer) uint32 {
-	q := (*[4]byte)(p)
-	if goarch.BigEndian {
-		return uint32(q[3]) | uint32(q[2])<<8 | uint32(q[1])<<16 | uint32(q[0])<<24
-	}
-	return uint32(q[0]) | uint32(q[1])<<8 | uint32(q[2])<<16 | uint32(q[3])<<24
-}
-
-func readUnaligned64(p unsafe.Pointer) uint64 {
-	q := (*[8]byte)(p)
-	if goarch.BigEndian {
-		return uint64(q[7]) | uint64(q[6])<<8 | uint64(q[5])<<16 | uint64(q[4])<<24 |
-			uint64(q[3])<<32 | uint64(q[2])<<40 | uint64(q[1])<<48 | uint64(q[0])<<56
-	}
-	return uint64(q[0]) | uint64(q[1])<<8 | uint64(q[2])<<16 | uint64(q[3])<<24 | uint64(q[4])<<32 | uint64(q[5])<<40 | uint64(q[6])<<48 | uint64(q[7])<<56
-}
diff --git a/contrib/go/_std_1.18/src/runtime/asan0.go b/contrib/go/_std_1.18/src/runtime/asan0.go
deleted file mode 100644
index d5478d6bee..0000000000
--- a/contrib/go/_std_1.18/src/runtime/asan0.go
+++ /dev/null
@@ -1,22 +0,0 @@
-// Copyright 2021 The Go Authors.  All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build !asan
-
-// Dummy ASan support API, used when not built with -asan.
-
-package runtime
-
-import (
-	"unsafe"
-)
-
-const asanenabled = false
-
-// Because asanenabled is false, none of these functions should be called.
-
-func asanread(addr unsafe.Pointer, sz uintptr)     { throw("asan") }
-func asanwrite(addr unsafe.Pointer, sz uintptr)    { throw("asan") }
-func asanunpoison(addr unsafe.Pointer, sz uintptr) { throw("asan") }
-func asanpoison(addr unsafe.Pointer, sz uintptr)   { throw("asan") }
diff --git a/contrib/go/_std_1.18/src/runtime/asm_amd64.s b/contrib/go/_std_1.18/src/runtime/asm_amd64.s
deleted file mode 100644
index c08ae610fb..0000000000
--- a/contrib/go/_std_1.18/src/runtime/asm_amd64.s
+++ /dev/null
@@ -1,2036 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-#include "go_asm.h"
-#include "go_tls.h"
-#include "funcdata.h"
-#include "textflag.h"
-#include "cgo/abi_amd64.h"
-
-// _rt0_amd64 is common startup code for most amd64 systems when using
-// internal linking. This is the entry point for the program from the
-// kernel for an ordinary -buildmode=exe program. The stack holds the
-// number of arguments and the C-style argv.
-TEXT _rt0_amd64(SB),NOSPLIT,$-8
-	MOVQ	0(SP), DI	// argc
-	LEAQ	8(SP), SI	// argv
-	JMP	runtime·rt0_go(SB)
-
-// main is common startup code for most amd64 systems when using
-// external linking. The C startup code will call the symbol "main"
-// passing argc and argv in the usual C ABI registers DI and SI.
-TEXT main(SB),NOSPLIT,$-8
-	JMP	runtime·rt0_go(SB)
-
-// _rt0_amd64_lib is common startup code for most amd64 systems when
-// using -buildmode=c-archive or -buildmode=c-shared. The linker will
-// arrange to invoke this function as a global constructor (for
-// c-archive) or when the shared library is loaded (for c-shared).
-// We expect argc and argv to be passed in the usual C ABI registers
-// DI and SI.
-TEXT _rt0_amd64_lib(SB),NOSPLIT,$0
-	// Transition from C ABI to Go ABI.
-	PUSH_REGS_HOST_TO_ABI0()
-
-	MOVQ	DI, _rt0_amd64_lib_argc<>(SB)
-	MOVQ	SI, _rt0_amd64_lib_argv<>(SB)
-
-	// Synchronous initialization.
-	CALL	runtime·libpreinit(SB)
-
-	// Create a new thread to finish Go runtime initialization.
-	MOVQ	_cgo_sys_thread_create(SB), AX
-	TESTQ	AX, AX
-	JZ	nocgo
-
-	// We're calling back to C.
-	// Align stack per ELF ABI requirements.
-	MOVQ	SP, BX  // Callee-save in C ABI
-	ANDQ	$~15, SP
-	MOVQ	$_rt0_amd64_lib_go(SB), DI
-	MOVQ	$0, SI
-	CALL	AX
-	MOVQ	BX, SP
-	JMP	restore
-
-nocgo:
-	ADJSP	$16
-	MOVQ	$0x800000, 0(SP)		// stacksize
-	MOVQ	$_rt0_amd64_lib_go(SB), AX
-	MOVQ	AX, 8(SP)			// fn
-	CALL	runtime·newosproc0(SB)
-	ADJSP	$-16
-
-restore:
-	POP_REGS_HOST_TO_ABI0()
-	RET
-
-// _rt0_amd64_lib_go initializes the Go runtime.
-// This is started in a separate thread by _rt0_amd64_lib.
-TEXT _rt0_amd64_lib_go(SB),NOSPLIT,$0
-	MOVQ	_rt0_amd64_lib_argc<>(SB), DI
-	MOVQ	_rt0_amd64_lib_argv<>(SB), SI
-	JMP	runtime·rt0_go(SB)
-
-DATA _rt0_amd64_lib_argc<>(SB)/8, $0
-GLOBL _rt0_amd64_lib_argc<>(SB),NOPTR, $8
-DATA _rt0_amd64_lib_argv<>(SB)/8, $0
-GLOBL _rt0_amd64_lib_argv<>(SB),NOPTR, $8
-
-#ifdef GOAMD64_v2
-DATA bad_cpu_msg<>+0x00(SB)/84, $"This program can only be run on AMD64 processors with v2 microarchitecture support.\n"
-#endif
-
-#ifdef GOAMD64_v3
-DATA bad_cpu_msg<>+0x00(SB)/84, $"This program can only be run on AMD64 processors with v3 microarchitecture support.\n"
-#endif
-
-#ifdef GOAMD64_v4
-DATA bad_cpu_msg<>+0x00(SB)/84, $"This program can only be run on AMD64 processors with v4 microarchitecture support.\n"
-#endif
-
-GLOBL bad_cpu_msg<>(SB), RODATA, $84
-
-// Define a list of AMD64 microarchitecture level features
-// https://en.wikipedia.org/wiki/X86-64#Microarchitecture_levels
-
-                     // SSE3     SSSE3    CMPXCHNG16 SSE4.1    SSE4.2    POPCNT
-#define V2_FEATURES_CX (1 << 0 | 1 << 9 | 1 << 13  | 1 << 19 | 1 << 20 | 1 << 23)
-                         // LAHF/SAHF
-#define V2_EXT_FEATURES_CX (1 << 0)
-                                      // FMA       MOVBE     OSXSAVE   AVX       F16C
-#define V3_FEATURES_CX (V2_FEATURES_CX | 1 << 12 | 1 << 22 | 1 << 27 | 1 << 28 | 1 << 29)
-                                              // ABM (FOR LZNCT)
-#define V3_EXT_FEATURES_CX (V2_EXT_FEATURES_CX | 1 << 5)
-                         // BMI1     AVX2     BMI2
-#define V3_EXT_FEATURES_BX (1 << 3 | 1 << 5 | 1 << 8)
-                       // XMM      YMM
-#define V3_OS_SUPPORT_AX (1 << 1 | 1 << 2)
-
-#define V4_FEATURES_CX V3_FEATURES_CX
-
-#define V4_EXT_FEATURES_CX V3_EXT_FEATURES_CX
-                                              // AVX512F   AVX512DQ  AVX512CD  AVX512BW  AVX512VL
-#define V4_EXT_FEATURES_BX (V3_EXT_FEATURES_BX | 1 << 16 | 1 << 17 | 1 << 28 | 1 << 30 | 1 << 31)
-                                          // OPMASK   ZMM
-#define V4_OS_SUPPORT_AX (V3_OS_SUPPORT_AX | 1 << 5 | (1 << 6 | 1 << 7))
-
-#ifdef GOAMD64_v2
-#define NEED_MAX_CPUID 0x80000001
-#define NEED_FEATURES_CX V2_FEATURES_CX
-#define NEED_EXT_FEATURES_CX V2_EXT_FEATURES_CX
-#endif
-
-#ifdef GOAMD64_v3
-#define NEED_MAX_CPUID 0x80000001
-#define NEED_FEATURES_CX V3_FEATURES_CX
-#define NEED_EXT_FEATURES_CX V3_EXT_FEATURES_CX
-#define NEED_EXT_FEATURES_BX V3_EXT_FEATURES_BX
-#define NEED_OS_SUPPORT_AX V3_OS_SUPPORT_AX
-#endif
-
-#ifdef GOAMD64_v4
-#define NEED_MAX_CPUID 0x80000001
-#define NEED_FEATURES_CX V4_FEATURES_CX
-#define NEED_EXT_FEATURES_CX V4_EXT_FEATURES_CX
-#define NEED_EXT_FEATURES_BX V4_EXT_FEATURES_BX
-
-// Downgrading v4 OS checks on Darwin for now, see CL 285572.
-#ifdef GOOS_darwin
-#define NEED_OS_SUPPORT_AX V3_OS_SUPPORT_AX
-#else
-#define NEED_OS_SUPPORT_AX V4_OS_SUPPORT_AX
-#endif
-
-#endif
-
-TEXT runtime·rt0_go(SB),NOSPLIT|TOPFRAME,$0
-	// copy arguments forward on an even stack
-	MOVQ	DI, AX		// argc
-	MOVQ	SI, BX		// argv
-	SUBQ	$(5*8), SP		// 3args 2auto
-	ANDQ	$~15, SP
-	MOVQ	AX, 24(SP)
-	MOVQ	BX, 32(SP)
-
-	// create istack out of the given (operating system) stack.
-	// _cgo_init may update stackguard.
-	MOVQ	$runtime·g0(SB), DI
-	LEAQ	(-64*1024+104)(SP), BX
-	MOVQ	BX, g_stackguard0(DI)
-	MOVQ	BX, g_stackguard1(DI)
-	MOVQ	BX, (g_stack+stack_lo)(DI)
-	MOVQ	SP, (g_stack+stack_hi)(DI)
-
-	// find out information about the processor we're on
-	MOVL	$0, AX
-	CPUID
-	CMPL	AX, $0
-	JE	nocpuinfo
-
-	CMPL	BX, $0x756E6547  // "Genu"
-	JNE	notintel
-	CMPL	DX, $0x49656E69  // "ineI"
-	JNE	notintel
-	CMPL	CX, $0x6C65746E  // "ntel"
-	JNE	notintel
-	MOVB	$1, runtime·isIntel(SB)
-
-notintel:
-	// Load EAX=1 cpuid flags
-	MOVL	$1, AX
-	CPUID
-	MOVL	AX, runtime·processorVersionInfo(SB)
-
-nocpuinfo:
-	// if there is an _cgo_init, call it.
-	MOVQ	_cgo_init(SB), AX
-	TESTQ	AX, AX
-	JZ	needtls
-	// arg 1: g0, already in DI
-	MOVQ	$setg_gcc<>(SB), SI // arg 2: setg_gcc
-#ifdef GOOS_android
-	MOVQ	$runtime·tls_g(SB), DX 	// arg 3: &tls_g
-	// arg 4: TLS base, stored in slot 0 (Android's TLS_SLOT_SELF).
-	// Compensate for tls_g (+16).
-	MOVQ	-16(TLS), CX
-#else
-	MOVQ	$0, DX	// arg 3, 4: not used when using platform's TLS
-	MOVQ	$0, CX
-#endif
-#ifdef GOOS_windows
-	// Adjust for the Win64 calling convention.
-	MOVQ	CX, R9 // arg 4
-	MOVQ	DX, R8 // arg 3
-	MOVQ	SI, DX // arg 2
-	MOVQ	DI, CX // arg 1
-#endif
-	CALL	AX
-
-	// update stackguard after _cgo_init
-	MOVQ	$runtime·g0(SB), CX
-	MOVQ	(g_stack+stack_lo)(CX), AX
-	ADDQ	$const__StackGuard, AX
-	MOVQ	AX, g_stackguard0(CX)
-	MOVQ	AX, g_stackguard1(CX)
-
-#ifndef GOOS_windows
-	JMP ok
-#endif
-needtls:
-#ifdef GOOS_plan9
-	// skip TLS setup on Plan 9
-	JMP ok
-#endif
-#ifdef GOOS_solaris
-	// skip TLS setup on Solaris
-	JMP ok
-#endif
-#ifdef GOOS_illumos
-	// skip TLS setup on illumos
-	JMP ok
-#endif
-#ifdef GOOS_darwin
-	// skip TLS setup on Darwin
-	JMP ok
-#endif
-#ifdef GOOS_openbsd
-	// skip TLS setup on OpenBSD
-	JMP ok
-#endif
-
-	LEAQ	runtime·m0+m_tls(SB), DI
-	CALL	runtime·settls(SB)
-
-	// store through it, to make sure it works
-	get_tls(BX)
-	MOVQ	$0x123, g(BX)
-	MOVQ	runtime·m0+m_tls(SB), AX
-	CMPQ	AX, $0x123
-	JEQ 2(PC)
-	CALL	runtime·abort(SB)
-ok:
-	// set the per-goroutine and per-mach "registers"
-	get_tls(BX)
-	LEAQ	runtime·g0(SB), CX
-	MOVQ	CX, g(BX)
-	LEAQ	runtime·m0(SB), AX
-
-	// save m->g0 = g0
-	MOVQ	CX, m_g0(AX)
-	// save m0 to g0->m
-	MOVQ	AX, g_m(CX)
-
-	CLD				// convention is D is always left cleared
-
-	// Check GOAMD64 reqirements
-	// We need to do this after setting up TLS, so that
-	// we can report an error if there is a failure. See issue 49586.
-#ifdef NEED_FEATURES_CX
-	MOVL	$0, AX
-	CPUID
-	CMPL	AX, $0
-	JE	bad_cpu
-	MOVL	$1, AX
-	CPUID
-	ANDL	$NEED_FEATURES_CX, CX
-	CMPL	CX, $NEED_FEATURES_CX
-	JNE	bad_cpu
-#endif
-
-#ifdef NEED_MAX_CPUID
-	MOVL	$0x80000000, AX
-	CPUID
-	CMPL	AX, $NEED_MAX_CPUID
-	JL	bad_cpu
-#endif
-
-#ifdef NEED_EXT_FEATURES_BX
-	MOVL	$7, AX
-	MOVL	$0, CX
-	CPUID
-	ANDL	$NEED_EXT_FEATURES_BX, BX
-	CMPL	BX, $NEED_EXT_FEATURES_BX
-	JNE	bad_cpu
-#endif
-
-#ifdef NEED_EXT_FEATURES_CX
-	MOVL	$0x80000001, AX
-	CPUID
-	ANDL	$NEED_EXT_FEATURES_CX, CX
-	CMPL	CX, $NEED_EXT_FEATURES_CX
-	JNE	bad_cpu
-#endif
-
-#ifdef NEED_OS_SUPPORT_AX
-	XORL    CX, CX
-	XGETBV
-	ANDL	$NEED_OS_SUPPORT_AX, AX
-	CMPL	AX, $NEED_OS_SUPPORT_AX
-	JNE	bad_cpu
-#endif
-
-	CALL	runtime·check(SB)
-
-	MOVL	24(SP), AX		// copy argc
-	MOVL	AX, 0(SP)
-	MOVQ	32(SP), AX		// copy argv
-	MOVQ	AX, 8(SP)
-	CALL	runtime·args(SB)
-	CALL	runtime·osinit(SB)
-	CALL	runtime·schedinit(SB)
-
-	// create a new goroutine to start program
-	MOVQ	$runtime·mainPC(SB), AX		// entry
-	PUSHQ	AX
-	CALL	runtime·newproc(SB)
-	POPQ	AX
-
-	// start this M
-	CALL	runtime·mstart(SB)
-
-	CALL	runtime·abort(SB)	// mstart should never return
-	RET
-
-bad_cpu: // show that the program requires a certain microarchitecture level.
-	MOVQ	$2, 0(SP)
-	MOVQ	$bad_cpu_msg<>(SB), AX
-	MOVQ	AX, 8(SP)
-	MOVQ	$84, 16(SP)
-	CALL	runtime·write(SB)
-	MOVQ	$1, 0(SP)
-	CALL	runtime·exit(SB)
-	CALL	runtime·abort(SB)
-	RET
-
-	// Prevent dead-code elimination of debugCallV2, which is
-	// intended to be called by debuggers.
-	MOVQ	$runtime·debugCallV2<ABIInternal>(SB), AX
-	RET
-
-// mainPC is a function value for runtime.main, to be passed to newproc.
-// The reference to runtime.main is made via ABIInternal, since the
-// actual function (not the ABI0 wrapper) is needed by newproc.
-DATA	runtime·mainPC+0(SB)/8,$runtime·main<ABIInternal>(SB)
-GLOBL	runtime·mainPC(SB),RODATA,$8
-
-TEXT runtime·breakpoint(SB),NOSPLIT,$0-0
-	BYTE	$0xcc
-	RET
-
-TEXT runtime·asminit(SB),NOSPLIT,$0-0
-	// No per-thread init.
-	RET
-
-TEXT runtime·mstart(SB),NOSPLIT|TOPFRAME,$0
-	CALL	runtime·mstart0(SB)
-	RET // not reached
-
-/*
- *  go-routine
- */
-
-// func gogo(buf *gobuf)
-// restore state from Gobuf; longjmp
-TEXT runtime·gogo(SB), NOSPLIT, $0-8
-	MOVQ	buf+0(FP), BX		// gobuf
-	MOVQ	gobuf_g(BX), DX
-	MOVQ	0(DX), CX		// make sure g != nil
-	JMP	gogo<>(SB)
-
-TEXT gogo<>(SB), NOSPLIT, $0
-	get_tls(CX)
-	MOVQ	DX, g(CX)
-	MOVQ	DX, R14		// set the g register
-	MOVQ	gobuf_sp(BX), SP	// restore SP
-	MOVQ	gobuf_ret(BX), AX
-	MOVQ	gobuf_ctxt(BX), DX
-	MOVQ	gobuf_bp(BX), BP
-	MOVQ	$0, gobuf_sp(BX)	// clear to help garbage collector
-	MOVQ	$0, gobuf_ret(BX)
-	MOVQ	$0, gobuf_ctxt(BX)
-	MOVQ	$0, gobuf_bp(BX)
-	MOVQ	gobuf_pc(BX), BX
-	JMP	BX
-
-// func mcall(fn func(*g))
-// Switch to m->g0's stack, call fn(g).
-// Fn must never return. It should gogo(&g->sched)
-// to keep running g.
-TEXT runtime·mcall<ABIInternal>(SB), NOSPLIT, $0-8
-	MOVQ	AX, DX	// DX = fn
-
-	// save state in g->sched
-	MOVQ	0(SP), BX	// caller's PC
-	MOVQ	BX, (g_sched+gobuf_pc)(R14)
-	LEAQ	fn+0(FP), BX	// caller's SP
-	MOVQ	BX, (g_sched+gobuf_sp)(R14)
-	MOVQ	BP, (g_sched+gobuf_bp)(R14)
-
-	// switch to m->g0 & its stack, call fn
-	MOVQ	g_m(R14), BX
-	MOVQ	m_g0(BX), SI	// SI = g.m.g0
-	CMPQ	SI, R14	// if g == m->g0 call badmcall
-	JNE	goodm
-	JMP	runtime·badmcall(SB)
-goodm:
-	MOVQ	R14, AX		// AX (and arg 0) = g
-	MOVQ	SI, R14		// g = g.m.g0
-	get_tls(CX)		// Set G in TLS
-	MOVQ	R14, g(CX)
-	MOVQ	(g_sched+gobuf_sp)(R14), SP	// sp = g0.sched.sp
-	PUSHQ	AX	// open up space for fn's arg spill slot
-	MOVQ	0(DX), R12
-	CALL	R12		// fn(g)
-	POPQ	AX
-	JMP	runtime·badmcall2(SB)
-	RET
-
-// systemstack_switch is a dummy routine that systemstack leaves at the bottom
-// of the G stack. We need to distinguish the routine that
-// lives at the bottom of the G stack from the one that lives
-// at the top of the system stack because the one at the top of
-// the system stack terminates the stack walk (see topofstack()).
-TEXT runtime·systemstack_switch(SB), NOSPLIT, $0-0
-	RET
-
-// func systemstack(fn func())
-TEXT runtime·systemstack(SB), NOSPLIT, $0-8
-	MOVQ	fn+0(FP), DI	// DI = fn
-	get_tls(CX)
-	MOVQ	g(CX), AX	// AX = g
-	MOVQ	g_m(AX), BX	// BX = m
-
-	CMPQ	AX, m_gsignal(BX)
-	JEQ	noswitch
-
-	MOVQ	m_g0(BX), DX	// DX = g0
-	CMPQ	AX, DX
-	JEQ	noswitch
-
-	CMPQ	AX, m_curg(BX)
-	JNE	bad
-
-	// switch stacks
-	// save our state in g->sched. Pretend to
-	// be systemstack_switch if the G stack is scanned.
-	CALL	gosave_systemstack_switch<>(SB)
-
-	// switch to g0
-	MOVQ	DX, g(CX)
-	MOVQ	DX, R14 // set the g register
-	MOVQ	(g_sched+gobuf_sp)(DX), BX
-	MOVQ	BX, SP
-
-	// call target function
-	MOVQ	DI, DX
-	MOVQ	0(DI), DI
-	CALL	DI
-
-	// switch back to g
-	get_tls(CX)
-	MOVQ	g(CX), AX
-	MOVQ	g_m(AX), BX
-	MOVQ	m_curg(BX), AX
-	MOVQ	AX, g(CX)
-	MOVQ	(g_sched+gobuf_sp)(AX), SP
-	MOVQ	$0, (g_sched+gobuf_sp)(AX)
-	RET
-
-noswitch:
-	// already on m stack; tail call the function
-	// Using a tail call here cleans up tracebacks since we won't stop
-	// at an intermediate systemstack.
-	MOVQ	DI, DX
-	MOVQ	0(DI), DI
-	JMP	DI
-
-bad:
-	// Bad: g is not gsignal, not g0, not curg. What is it?
-	MOVQ	$runtime·badsystemstack(SB), AX
-	CALL	AX
-	INT	$3
-
-
-/*
- * support for morestack
- */
-
-// Called during function prolog when more stack is needed.
-//
-// The traceback routines see morestack on a g0 as being
-// the top of a stack (for example, morestack calling newstack
-// calling the scheduler calling newm calling gc), so we must
-// record an argument size. For that purpose, it has no arguments.
-TEXT runtime·morestack(SB),NOSPLIT,$0-0
-	// Cannot grow scheduler stack (m->g0).
-	get_tls(CX)
-	MOVQ	g(CX), BX
-	MOVQ	g_m(BX), BX
-	MOVQ	m_g0(BX), SI
-	CMPQ	g(CX), SI
-	JNE	3(PC)
-	CALL	runtime·badmorestackg0(SB)
-	CALL	runtime·abort(SB)
-
-	// Cannot grow signal stack (m->gsignal).
-	MOVQ	m_gsignal(BX), SI
-	CMPQ	g(CX), SI
-	JNE	3(PC)
-	CALL	runtime·badmorestackgsignal(SB)
-	CALL	runtime·abort(SB)
-
-	// Called from f.
-	// Set m->morebuf to f's caller.
-	NOP	SP	// tell vet SP changed - stop checking offsets
-	MOVQ	8(SP), AX	// f's caller's PC
-	MOVQ	AX, (m_morebuf+gobuf_pc)(BX)
-	LEAQ	16(SP), AX	// f's caller's SP
-	MOVQ	AX, (m_morebuf+gobuf_sp)(BX)
-	get_tls(CX)
-	MOVQ	g(CX), SI
-	MOVQ	SI, (m_morebuf+gobuf_g)(BX)
-
-	// Set g->sched to context in f.
-	MOVQ	0(SP), AX // f's PC
-	MOVQ	AX, (g_sched+gobuf_pc)(SI)
-	LEAQ	8(SP), AX // f's SP
-	MOVQ	AX, (g_sched+gobuf_sp)(SI)
-	MOVQ	BP, (g_sched+gobuf_bp)(SI)
-	MOVQ	DX, (g_sched+gobuf_ctxt)(SI)
-
-	// Call newstack on m->g0's stack.
-	MOVQ	m_g0(BX), BX
-	MOVQ	BX, g(CX)
-	MOVQ	(g_sched+gobuf_sp)(BX), SP
-	CALL	runtime·newstack(SB)
-	CALL	runtime·abort(SB)	// crash if newstack returns
-	RET
-
-// morestack but not preserving ctxt.
-TEXT runtime·morestack_noctxt(SB),NOSPLIT,$0
-	MOVL	$0, DX
-	JMP	runtime·morestack(SB)
-
-// spillArgs stores return values from registers to a *internal/abi.RegArgs in R12.
-TEXT ·spillArgs(SB),NOSPLIT,$0-0
-	MOVQ AX, 0(R12)
-	MOVQ BX, 8(R12)
-	MOVQ CX, 16(R12)
-	MOVQ DI, 24(R12)
-	MOVQ SI, 32(R12)
-	MOVQ R8, 40(R12)
-	MOVQ R9, 48(R12)
-	MOVQ R10, 56(R12)
-	MOVQ R11, 64(R12)
-	MOVQ X0, 72(R12)
-	MOVQ X1, 80(R12)
-	MOVQ X2, 88(R12)
-	MOVQ X3, 96(R12)
-	MOVQ X4, 104(R12)
-	MOVQ X5, 112(R12)
-	MOVQ X6, 120(R12)
-	MOVQ X7, 128(R12)
-	MOVQ X8, 136(R12)
-	MOVQ X9, 144(R12)
-	MOVQ X10, 152(R12)
-	MOVQ X11, 160(R12)
-	MOVQ X12, 168(R12)
-	MOVQ X13, 176(R12)
-	MOVQ X14, 184(R12)
-	RET
-
-// unspillArgs loads args into registers from a *internal/abi.RegArgs in R12.
-TEXT ·unspillArgs(SB),NOSPLIT,$0-0
-	MOVQ 0(R12), AX
-	MOVQ 8(R12), BX
-	MOVQ 16(R12), CX
-	MOVQ 24(R12), DI
-	MOVQ 32(R12), SI
-	MOVQ 40(R12), R8
-	MOVQ 48(R12), R9
-	MOVQ 56(R12), R10
-	MOVQ 64(R12), R11
-	MOVQ 72(R12), X0
-	MOVQ 80(R12), X1
-	MOVQ 88(R12), X2
-	MOVQ 96(R12), X3
-	MOVQ 104(R12), X4
-	MOVQ 112(R12), X5
-	MOVQ 120(R12), X6
-	MOVQ 128(R12), X7
-	MOVQ 136(R12), X8
-	MOVQ 144(R12), X9
-	MOVQ 152(R12), X10
-	MOVQ 160(R12), X11
-	MOVQ 168(R12), X12
-	MOVQ 176(R12), X13
-	MOVQ 184(R12), X14
-	RET
-
-// reflectcall: call a function with the given argument list
-// func call(stackArgsType *_type, f *FuncVal, stackArgs *byte, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs).
-// we don't have variable-sized frames, so we use a small number
-// of constant-sized-frame functions to encode a few bits of size in the pc.
-// Caution: ugly multiline assembly macros in your future!
-
-#define DISPATCH(NAME,MAXSIZE)		\
-	CMPQ	CX, $MAXSIZE;		\
-	JA	3(PC);			\
-	MOVQ	$NAME(SB), AX;		\
-	JMP	AX
-// Note: can't just "JMP NAME(SB)" - bad inlining results.
-
-TEXT ·reflectcall(SB), NOSPLIT, $0-48
-	MOVLQZX frameSize+32(FP), CX
-	DISPATCH(runtime·call16, 16)
-	DISPATCH(runtime·call32, 32)
-	DISPATCH(runtime·call64, 64)
-	DISPATCH(runtime·call128, 128)
-	DISPATCH(runtime·call256, 256)
-	DISPATCH(runtime·call512, 512)
-	DISPATCH(runtime·call1024, 1024)
-	DISPATCH(runtime·call2048, 2048)
-	DISPATCH(runtime·call4096, 4096)
-	DISPATCH(runtime·call8192, 8192)
-	DISPATCH(runtime·call16384, 16384)
-	DISPATCH(runtime·call32768, 32768)
-	DISPATCH(runtime·call65536, 65536)
-	DISPATCH(runtime·call131072, 131072)
-	DISPATCH(runtime·call262144, 262144)
-	DISPATCH(runtime·call524288, 524288)
-	DISPATCH(runtime·call1048576, 1048576)
-	DISPATCH(runtime·call2097152, 2097152)
-	DISPATCH(runtime·call4194304, 4194304)
-	DISPATCH(runtime·call8388608, 8388608)
-	DISPATCH(runtime·call16777216, 16777216)
-	DISPATCH(runtime·call33554432, 33554432)
-	DISPATCH(runtime·call67108864, 67108864)
-	DISPATCH(runtime·call134217728, 134217728)
-	DISPATCH(runtime·call268435456, 268435456)
-	DISPATCH(runtime·call536870912, 536870912)
-	DISPATCH(runtime·call1073741824, 1073741824)
-	MOVQ	$runtime·badreflectcall(SB), AX
-	JMP	AX
-
-#define CALLFN(NAME,MAXSIZE)			\
-TEXT NAME(SB), WRAPPER, $MAXSIZE-48;		\
-	NO_LOCAL_POINTERS;			\
-	/* copy arguments to stack */		\
-	MOVQ	stackArgs+16(FP), SI;		\
-	MOVLQZX stackArgsSize+24(FP), CX;		\
-	MOVQ	SP, DI;				\
-	REP;MOVSB;				\
-	/* set up argument registers */		\
-	MOVQ    regArgs+40(FP), R12;		\
-	CALL    ·unspillArgs(SB);		\
-	/* call function */			\
-	MOVQ	f+8(FP), DX;			\
-	PCDATA  $PCDATA_StackMapIndex, $0;	\
-	MOVQ	(DX), R12;			\
-	CALL	R12;				\
-	/* copy register return values back */		\
-	MOVQ    regArgs+40(FP), R12;		\
-	CALL    ·spillArgs(SB);		\
-	MOVLQZX	stackArgsSize+24(FP), CX;		\
-	MOVLQZX	stackRetOffset+28(FP), BX;		\
-	MOVQ	stackArgs+16(FP), DI;		\
-	MOVQ	stackArgsType+0(FP), DX;		\
-	MOVQ	SP, SI;				\
-	ADDQ	BX, DI;				\
-	ADDQ	BX, SI;				\
-	SUBQ	BX, CX;				\
-	CALL	callRet<>(SB);			\
-	RET
-
-// callRet copies return values back at the end of call*. This is a
-// separate function so it can allocate stack space for the arguments
-// to reflectcallmove. It does not follow the Go ABI; it expects its
-// arguments in registers.
-TEXT callRet<>(SB), NOSPLIT, $40-0
-	NO_LOCAL_POINTERS
-	MOVQ	DX, 0(SP)
-	MOVQ	DI, 8(SP)
-	MOVQ	SI, 16(SP)
-	MOVQ	CX, 24(SP)
-	MOVQ	R12, 32(SP)
-	CALL	runtime·reflectcallmove(SB)
-	RET
-
-CALLFN(·call16, 16)
-CALLFN(·call32, 32)
-CALLFN(·call64, 64)
-CALLFN(·call128, 128)
-CALLFN(·call256, 256)
-CALLFN(·call512, 512)
-CALLFN(·call1024, 1024)
-CALLFN(·call2048, 2048)
-CALLFN(·call4096, 4096)
-CALLFN(·call8192, 8192)
-CALLFN(·call16384, 16384)
-CALLFN(·call32768, 32768)
-CALLFN(·call65536, 65536)
-CALLFN(·call131072, 131072)
-CALLFN(·call262144, 262144)
-CALLFN(·call524288, 524288)
-CALLFN(·call1048576, 1048576)
-CALLFN(·call2097152, 2097152)
-CALLFN(·call4194304, 4194304)
-CALLFN(·call8388608, 8388608)
-CALLFN(·call16777216, 16777216)
-CALLFN(·call33554432, 33554432)
-CALLFN(·call67108864, 67108864)
-CALLFN(·call134217728, 134217728)
-CALLFN(·call268435456, 268435456)
-CALLFN(·call536870912, 536870912)
-CALLFN(·call1073741824, 1073741824)
-
-TEXT runtime·procyield(SB),NOSPLIT,$0-0
-	MOVL	cycles+0(FP), AX
-again:
-	PAUSE
-	SUBL	$1, AX
-	JNZ	again
-	RET
-
-
-TEXT ·publicationBarrier(SB),NOSPLIT,$0-0
-	// Stores are already ordered on x86, so this is just a
-	// compile barrier.
-	RET
-
-// Save state of caller into g->sched,
-// but using fake PC from systemstack_switch.
-// Must only be called from functions with no locals ($0)
-// or else unwinding from systemstack_switch is incorrect.
-// Smashes R9.
-TEXT gosave_systemstack_switch<>(SB),NOSPLIT,$0
-	MOVQ	$runtime·systemstack_switch(SB), R9
-	MOVQ	R9, (g_sched+gobuf_pc)(R14)
-	LEAQ	8(SP), R9
-	MOVQ	R9, (g_sched+gobuf_sp)(R14)
-	MOVQ	$0, (g_sched+gobuf_ret)(R14)
-	MOVQ	BP, (g_sched+gobuf_bp)(R14)
-	// Assert ctxt is zero. See func save.
-	MOVQ	(g_sched+gobuf_ctxt)(R14), R9
-	TESTQ	R9, R9
-	JZ	2(PC)
-	CALL	runtime·abort(SB)
-	RET
-
-// func asmcgocall_no_g(fn, arg unsafe.Pointer)
-// Call fn(arg) aligned appropriately for the gcc ABI.
-// Called on a system stack, and there may be no g yet (during needm).
-TEXT ·asmcgocall_no_g(SB),NOSPLIT,$0-16
-	MOVQ	fn+0(FP), AX
-	MOVQ	arg+8(FP), BX
-	MOVQ	SP, DX
-	SUBQ	$32, SP
-	ANDQ	$~15, SP	// alignment
-	MOVQ	DX, 8(SP)
-	MOVQ	BX, DI		// DI = first argument in AMD64 ABI
-	MOVQ	BX, CX		// CX = first argument in Win64
-	CALL	AX
-	MOVQ	8(SP), DX
-	MOVQ	DX, SP
-	RET
-
-// func asmcgocall(fn, arg unsafe.Pointer) int32
-// Call fn(arg) on the scheduler stack,
-// aligned appropriately for the gcc ABI.
-// See cgocall.go for more details.
-TEXT ·asmcgocall(SB),NOSPLIT,$0-20
-	MOVQ	fn+0(FP), AX
-	MOVQ	arg+8(FP), BX
-
-	MOVQ	SP, DX
-
-	// Figure out if we need to switch to m->g0 stack.
-	// We get called to create new OS threads too, and those
-	// come in on the m->g0 stack already. Or we might already
-	// be on the m->gsignal stack.
-	get_tls(CX)
-	MOVQ	g(CX), DI
-	CMPQ	DI, $0
-	JEQ	nosave
-	MOVQ	g_m(DI), R8
-	MOVQ	m_gsignal(R8), SI
-	CMPQ	DI, SI
-	JEQ	nosave
-	MOVQ	m_g0(R8), SI
-	CMPQ	DI, SI
-	JEQ	nosave
-
-	// Switch to system stack.
-	CALL	gosave_systemstack_switch<>(SB)
-	MOVQ	SI, g(CX)
-	MOVQ	(g_sched+gobuf_sp)(SI), SP
-
-	// Now on a scheduling stack (a pthread-created stack).
-	// Make sure we have enough room for 4 stack-backed fast-call
-	// registers as per windows amd64 calling convention.
-	SUBQ	$64, SP
-	ANDQ	$~15, SP	// alignment for gcc ABI
-	MOVQ	DI, 48(SP)	// save g
-	MOVQ	(g_stack+stack_hi)(DI), DI
-	SUBQ	DX, DI
-	MOVQ	DI, 40(SP)	// save depth in stack (can't just save SP, as stack might be copied during a callback)
-	MOVQ	BX, DI		// DI = first argument in AMD64 ABI
-	MOVQ	BX, CX		// CX = first argument in Win64
-	CALL	AX
-
-	// Restore registers, g, stack pointer.
-	get_tls(CX)
-	MOVQ	48(SP), DI
-	MOVQ	(g_stack+stack_hi)(DI), SI
-	SUBQ	40(SP), SI
-	MOVQ	DI, g(CX)
-	MOVQ	SI, SP
-
-	MOVL	AX, ret+16(FP)
-	RET
-
-nosave:
-	// Running on a system stack, perhaps even without a g.
-	// Having no g can happen during thread creation or thread teardown
-	// (see needm/dropm on Solaris, for example).
-	// This code is like the above sequence but without saving/restoring g
-	// and without worrying about the stack moving out from under us
-	// (because we're on a system stack, not a goroutine stack).
-	// The above code could be used directly if already on a system stack,
-	// but then the only path through this code would be a rare case on Solaris.
-	// Using this code for all "already on system stack" calls exercises it more,
-	// which should help keep it correct.
-	SUBQ	$64, SP
-	ANDQ	$~15, SP
-	MOVQ	$0, 48(SP)		// where above code stores g, in case someone looks during debugging
-	MOVQ	DX, 40(SP)	// save original stack pointer
-	MOVQ	BX, DI		// DI = first argument in AMD64 ABI
-	MOVQ	BX, CX		// CX = first argument in Win64
-	CALL	AX
-	MOVQ	40(SP), SI	// restore original stack pointer
-	MOVQ	SI, SP
-	MOVL	AX, ret+16(FP)
-	RET
-
-#ifdef GOOS_windows
-// Dummy TLS that's used on Windows so that we don't crash trying
-// to restore the G register in needm. needm and its callees are
-// very careful never to actually use the G, the TLS just can't be
-// unset since we're in Go code.
-GLOBL zeroTLS<>(SB),RODATA,$const_tlsSize
-#endif
-
-// func cgocallback(fn, frame unsafe.Pointer, ctxt uintptr)
-// See cgocall.go for more details.
-TEXT ·cgocallback(SB),NOSPLIT,$24-24
-	NO_LOCAL_POINTERS
-
-	// If g is nil, Go did not create the current thread.
-	// Call needm to obtain one m for temporary use.
-	// In this case, we're running on the thread stack, so there's
-	// lots of space, but the linker doesn't know. Hide the call from
-	// the linker analysis by using an indirect call through AX.
-	get_tls(CX)
-#ifdef GOOS_windows
-	MOVL	$0, BX
-	CMPQ	CX, $0
-	JEQ	2(PC)
-#endif
-	MOVQ	g(CX), BX
-	CMPQ	BX, $0
-	JEQ	needm
-	MOVQ	g_m(BX), BX
-	MOVQ	BX, savedm-8(SP)	// saved copy of oldm
-	JMP	havem
-needm:
-#ifdef GOOS_windows
-	// Set up a dummy TLS value. needm is careful not to use it,
-	// but it needs to be there to prevent autogenerated code from
-	// crashing when it loads from it.
-	// We don't need to clear it or anything later because needm
-	// will set up TLS properly.
-	MOVQ	$zeroTLS<>(SB), DI
-	CALL	runtime·settls(SB)
-#endif
-	// On some platforms (Windows) we cannot call needm through
-	// an ABI wrapper because there's no TLS set up, and the ABI
-	// wrapper will try to restore the G register (R14) from TLS.
-	// Clear X15 because Go expects it and we're not calling
-	// through a wrapper, but otherwise avoid setting the G
-	// register in the wrapper and call needm directly. It
-	// takes no arguments and doesn't return any values so
-	// there's no need to handle that. Clear R14 so that there's
-	// a bad value in there, in case needm tries to use it.
-	XORPS	X15, X15
-	XORQ    R14, R14
-	MOVQ	$runtime·needm<ABIInternal>(SB), AX
-	CALL	AX
-	MOVQ	$0, savedm-8(SP) // dropm on return
-	get_tls(CX)
-	MOVQ	g(CX), BX
-	MOVQ	g_m(BX), BX
-
-	// Set m->sched.sp = SP, so that if a panic happens
-	// during the function we are about to execute, it will
-	// have a valid SP to run on the g0 stack.
-	// The next few lines (after the havem label)
-	// will save this SP onto the stack and then write
-	// the same SP back to m->sched.sp. That seems redundant,
-	// but if an unrecovered panic happens, unwindm will
-	// restore the g->sched.sp from the stack location
-	// and then systemstack will try to use it. If we don't set it here,
-	// that restored SP will be uninitialized (typically 0) and
-	// will not be usable.
-	MOVQ	m_g0(BX), SI
-	MOVQ	SP, (g_sched+gobuf_sp)(SI)
-
-havem:
-	// Now there's a valid m, and we're running on its m->g0.
-	// Save current m->g0->sched.sp on stack and then set it to SP.
-	// Save current sp in m->g0->sched.sp in preparation for
-	// switch back to m->curg stack.
-	// NOTE: unwindm knows that the saved g->sched.sp is at 0(SP).
-	MOVQ	m_g0(BX), SI
-	MOVQ	(g_sched+gobuf_sp)(SI), AX
-	MOVQ	AX, 0(SP)
-	MOVQ	SP, (g_sched+gobuf_sp)(SI)
-
-	// Switch to m->curg stack and call runtime.cgocallbackg.
-	// Because we are taking over the execution of m->curg
-	// but *not* resuming what had been running, we need to
-	// save that information (m->curg->sched) so we can restore it.
-	// We can restore m->curg->sched.sp easily, because calling
-	// runtime.cgocallbackg leaves SP unchanged upon return.
-	// To save m->curg->sched.pc, we push it onto the curg stack and
-	// open a frame the same size as cgocallback's g0 frame.
-	// Once we switch to the curg stack, the pushed PC will appear
-	// to be the return PC of cgocallback, so that the traceback
-	// will seamlessly trace back into the earlier calls.
-	MOVQ	m_curg(BX), SI
-	MOVQ	SI, g(CX)
-	MOVQ	(g_sched+gobuf_sp)(SI), DI  // prepare stack as DI
-	MOVQ	(g_sched+gobuf_pc)(SI), BX
-	MOVQ	BX, -8(DI)  // "push" return PC on the g stack
-	// Gather our arguments into registers.
-	MOVQ	fn+0(FP), BX
-	MOVQ	frame+8(FP), CX
-	MOVQ	ctxt+16(FP), DX
-	// Compute the size of the frame, including return PC and, if
-	// GOEXPERIMENT=framepointer, the saved base pointer
-	LEAQ	fn+0(FP), AX
-	SUBQ	SP, AX   // AX is our actual frame size
-	SUBQ	AX, DI   // Allocate the same frame size on the g stack
-	MOVQ	DI, SP
-
-	MOVQ	BX, 0(SP)
-	MOVQ	CX, 8(SP)
-	MOVQ	DX, 16(SP)
-	MOVQ	$runtime·cgocallbackg(SB), AX
-	CALL	AX	// indirect call to bypass nosplit check. We're on a different stack now.
-
-	// Compute the size of the frame again. FP and SP have
-	// completely different values here than they did above,
-	// but only their difference matters.
-	LEAQ	fn+0(FP), AX
-	SUBQ	SP, AX
-
-	// Restore g->sched (== m->curg->sched) from saved values.
-	get_tls(CX)
-	MOVQ	g(CX), SI
-	MOVQ	SP, DI
-	ADDQ	AX, DI
-	MOVQ	-8(DI), BX
-	MOVQ	BX, (g_sched+gobuf_pc)(SI)
-	MOVQ	DI, (g_sched+gobuf_sp)(SI)
-
-	// Switch back to m->g0's stack and restore m->g0->sched.sp.
-	// (Unlike m->curg, the g0 goroutine never uses sched.pc,
-	// so we do not have to restore it.)
-	MOVQ	g(CX), BX
-	MOVQ	g_m(BX), BX
-	MOVQ	m_g0(BX), SI
-	MOVQ	SI, g(CX)
-	MOVQ	(g_sched+gobuf_sp)(SI), SP
-	MOVQ	0(SP), AX
-	MOVQ	AX, (g_sched+gobuf_sp)(SI)
-
-	// If the m on entry was nil, we called needm above to borrow an m
-	// for the duration of the call. Since the call is over, return it with dropm.
-	MOVQ	savedm-8(SP), BX
-	CMPQ	BX, $0
-	JNE	done
-	MOVQ	$runtime·dropm(SB), AX
-	CALL	AX
-#ifdef GOOS_windows
-	// We need to clear the TLS pointer in case the next
-	// thread that comes into Go tries to reuse that space
-	// but uses the same M.
-	XORQ	DI, DI
-	CALL	runtime·settls(SB)
-#endif
-done:
-
-	// Done!
-	RET
-
-// func setg(gg *g)
-// set g. for use by needm.
-TEXT runtime·setg(SB), NOSPLIT, $0-8
-	MOVQ	gg+0(FP), BX
-	get_tls(CX)
-	MOVQ	BX, g(CX)
-	RET
-
-// void setg_gcc(G*); set g called from gcc.
-TEXT setg_gcc<>(SB),NOSPLIT,$0
-	get_tls(AX)
-	MOVQ	DI, g(AX)
-	MOVQ	DI, R14 // set the g register
-	RET
-
-TEXT runtime·abort(SB),NOSPLIT,$0-0
-	INT	$3
-loop:
-	JMP	loop
-
-// check that SP is in range [g->stack.lo, g->stack.hi)
-TEXT runtime·stackcheck(SB), NOSPLIT, $0-0
-	get_tls(CX)
-	MOVQ	g(CX), AX
-	CMPQ	(g_stack+stack_hi)(AX), SP
-	JHI	2(PC)
-	CALL	runtime·abort(SB)
-	CMPQ	SP, (g_stack+stack_lo)(AX)
-	JHI	2(PC)
-	CALL	runtime·abort(SB)
-	RET
-
-// func cputicks() int64
-TEXT runtime·cputicks(SB),NOSPLIT,$0-0
-	CMPB	internal∕cpu·X86+const_offsetX86HasRDTSCP(SB), $1
-	JNE	fences
-	// Instruction stream serializing RDTSCP is supported.
-	// RDTSCP is supported by Intel Nehalem (2008) and
-	// AMD K8 Rev. F (2006) and newer.
-	RDTSCP
-done:
-	SHLQ	$32, DX
-	ADDQ	DX, AX
-	MOVQ	AX, ret+0(FP)
-	RET
-fences:
-	// MFENCE is instruction stream serializing and flushes the
-	// store buffers on AMD. The serialization semantics of LFENCE on AMD
-	// are dependent on MSR C001_1029 and CPU generation.
-	// LFENCE on Intel does wait for all previous instructions to have executed.
-	// Intel recommends MFENCE;LFENCE in its manuals before RDTSC to have all
-	// previous instructions executed and all previous loads and stores to globally visible.
-	// Using MFENCE;LFENCE here aligns the serializing properties without
-	// runtime detection of CPU manufacturer.
-	MFENCE
-	LFENCE
-	RDTSC
-	JMP done
-
-// func memhash(p unsafe.Pointer, h, s uintptr) uintptr
-// hash function using AES hardware instructions
-TEXT runtime·memhash<ABIInternal>(SB),NOSPLIT,$0-32
-	// AX = ptr to data
-	// BX = seed
-	// CX = size
-	CMPB	runtime·useAeshash(SB), $0
-	JEQ	noaes
-	JMP	aeshashbody<>(SB)
-noaes:
-	JMP	runtime·memhashFallback<ABIInternal>(SB)
-
-// func strhash(p unsafe.Pointer, h uintptr) uintptr
-TEXT runtime·strhash<ABIInternal>(SB),NOSPLIT,$0-24
-	// AX = ptr to string struct
-	// BX = seed
-	CMPB	runtime·useAeshash(SB), $0
-	JEQ	noaes
-	MOVQ	8(AX), CX	// length of string
-	MOVQ	(AX), AX	// string data
-	JMP	aeshashbody<>(SB)
-noaes:
-	JMP	runtime·strhashFallback<ABIInternal>(SB)
-
-// AX: data
-// BX: hash seed
-// CX: length
-// At return: AX = return value
-TEXT aeshashbody<>(SB),NOSPLIT,$0-0
-	// Fill an SSE register with our seeds.
-	MOVQ	BX, X0				// 64 bits of per-table hash seed
-	PINSRW	$4, CX, X0			// 16 bits of length
-	PSHUFHW $0, X0, X0			// repeat length 4 times total
-	MOVO	X0, X1				// save unscrambled seed
-	PXOR	runtime·aeskeysched(SB), X0	// xor in per-process seed
-	AESENC	X0, X0				// scramble seed
-
-	CMPQ	CX, $16
-	JB	aes0to15
-	JE	aes16
-	CMPQ	CX, $32
-	JBE	aes17to32
-	CMPQ	CX, $64
-	JBE	aes33to64
-	CMPQ	CX, $128
-	JBE	aes65to128
-	JMP	aes129plus
-
-aes0to15:
-	TESTQ	CX, CX
-	JE	aes0
-
-	ADDQ	$16, AX
-	TESTW	$0xff0, AX
-	JE	endofpage
-
-	// 16 bytes loaded at this address won't cross
-	// a page boundary, so we can load it directly.
-	MOVOU	-16(AX), X1
-	ADDQ	CX, CX
-	MOVQ	$masks<>(SB), AX
-	PAND	(AX)(CX*8), X1
-final1:
-	PXOR	X0, X1	// xor data with seed
-	AESENC	X1, X1	// scramble combo 3 times
-	AESENC	X1, X1
-	AESENC	X1, X1
-	MOVQ	X1, AX	// return X1
-	RET
-
-endofpage:
-	// address ends in 1111xxxx. Might be up against
-	// a page boundary, so load ending at last byte.
-	// Then shift bytes down using pshufb.
-	MOVOU	-32(AX)(CX*1), X1
-	ADDQ	CX, CX
-	MOVQ	$shifts<>(SB), AX
-	PSHUFB	(AX)(CX*8), X1
-	JMP	final1
-
-aes0:
-	// Return scrambled input seed
-	AESENC	X0, X0
-	MOVQ	X0, AX	// return X0
-	RET
-
-aes16:
-	MOVOU	(AX), X1
-	JMP	final1
-
-aes17to32:
-	// make second starting seed
-	PXOR	runtime·aeskeysched+16(SB), X1
-	AESENC	X1, X1
-
-	// load data to be hashed
-	MOVOU	(AX), X2
-	MOVOU	-16(AX)(CX*1), X3
-
-	// xor with seed
-	PXOR	X0, X2
-	PXOR	X1, X3
-
-	// scramble 3 times
-	AESENC	X2, X2
-	AESENC	X3, X3
-	AESENC	X2, X2
-	AESENC	X3, X3
-	AESENC	X2, X2
-	AESENC	X3, X3
-
-	// combine results
-	PXOR	X3, X2
-	MOVQ	X2, AX	// return X2
-	RET
-
-aes33to64:
-	// make 3 more starting seeds
-	MOVO	X1, X2
-	MOVO	X1, X3
-	PXOR	runtime·aeskeysched+16(SB), X1
-	PXOR	runtime·aeskeysched+32(SB), X2
-	PXOR	runtime·aeskeysched+48(SB), X3
-	AESENC	X1, X1
-	AESENC	X2, X2
-	AESENC	X3, X3
-
-	MOVOU	(AX), X4
-	MOVOU	16(AX), X5
-	MOVOU	-32(AX)(CX*1), X6
-	MOVOU	-16(AX)(CX*1), X7
-
-	PXOR	X0, X4
-	PXOR	X1, X5
-	PXOR	X2, X6
-	PXOR	X3, X7
-
-	AESENC	X4, X4
-	AESENC	X5, X5
-	AESENC	X6, X6
-	AESENC	X7, X7
-
-	AESENC	X4, X4
-	AESENC	X5, X5
-	AESENC	X6, X6
-	AESENC	X7, X7
-
-	AESENC	X4, X4
-	AESENC	X5, X5
-	AESENC	X6, X6
-	AESENC	X7, X7
-
-	PXOR	X6, X4
-	PXOR	X7, X5
-	PXOR	X5, X4
-	MOVQ	X4, AX	// return X4
-	RET
-
-aes65to128:
-	// make 7 more starting seeds
-	MOVO	X1, X2
-	MOVO	X1, X3
-	MOVO	X1, X4
-	MOVO	X1, X5
-	MOVO	X1, X6
-	MOVO	X1, X7
-	PXOR	runtime·aeskeysched+16(SB), X1
-	PXOR	runtime·aeskeysched+32(SB), X2
-	PXOR	runtime·aeskeysched+48(SB), X3
-	PXOR	runtime·aeskeysched+64(SB), X4
-	PXOR	runtime·aeskeysched+80(SB), X5
-	PXOR	runtime·aeskeysched+96(SB), X6
-	PXOR	runtime·aeskeysched+112(SB), X7
-	AESENC	X1, X1
-	AESENC	X2, X2
-	AESENC	X3, X3
-	AESENC	X4, X4
-	AESENC	X5, X5
-	AESENC	X6, X6
-	AESENC	X7, X7
-
-	// load data
-	MOVOU	(AX), X8
-	MOVOU	16(AX), X9
-	MOVOU	32(AX), X10
-	MOVOU	48(AX), X11
-	MOVOU	-64(AX)(CX*1), X12
-	MOVOU	-48(AX)(CX*1), X13
-	MOVOU	-32(AX)(CX*1), X14
-	MOVOU	-16(AX)(CX*1), X15
-
-	// xor with seed
-	PXOR	X0, X8
-	PXOR	X1, X9
-	PXOR	X2, X10
-	PXOR	X3, X11
-	PXOR	X4, X12
-	PXOR	X5, X13
-	PXOR	X6, X14
-	PXOR	X7, X15
-
-	// scramble 3 times
-	AESENC	X8, X8
-	AESENC	X9, X9
-	AESENC	X10, X10
-	AESENC	X11, X11
-	AESENC	X12, X12
-	AESENC	X13, X13
-	AESENC	X14, X14
-	AESENC	X15, X15
-
-	AESENC	X8, X8
-	AESENC	X9, X9
-	AESENC	X10, X10
-	AESENC	X11, X11
-	AESENC	X12, X12
-	AESENC	X13, X13
-	AESENC	X14, X14
-	AESENC	X15, X15
-
-	AESENC	X8, X8
-	AESENC	X9, X9
-	AESENC	X10, X10
-	AESENC	X11, X11
-	AESENC	X12, X12
-	AESENC	X13, X13
-	AESENC	X14, X14
-	AESENC	X15, X15
-
-	// combine results
-	PXOR	X12, X8
-	PXOR	X13, X9
-	PXOR	X14, X10
-	PXOR	X15, X11
-	PXOR	X10, X8
-	PXOR	X11, X9
-	PXOR	X9, X8
-	// X15 must be zero on return
-	PXOR	X15, X15
-	MOVQ	X8, AX	// return X8
-	RET
-
-aes129plus:
-	// make 7 more starting seeds
-	MOVO	X1, X2
-	MOVO	X1, X3
-	MOVO	X1, X4
-	MOVO	X1, X5
-	MOVO	X1, X6
-	MOVO	X1, X7
-	PXOR	runtime·aeskeysched+16(SB), X1
-	PXOR	runtime·aeskeysched+32(SB), X2
-	PXOR	runtime·aeskeysched+48(SB), X3
-	PXOR	runtime·aeskeysched+64(SB), X4
-	PXOR	runtime·aeskeysched+80(SB), X5
-	PXOR	runtime·aeskeysched+96(SB), X6
-	PXOR	runtime·aeskeysched+112(SB), X7
-	AESENC	X1, X1
-	AESENC	X2, X2
-	AESENC	X3, X3
-	AESENC	X4, X4
-	AESENC	X5, X5
-	AESENC	X6, X6
-	AESENC	X7, X7
-
-	// start with last (possibly overlapping) block
-	MOVOU	-128(AX)(CX*1), X8
-	MOVOU	-112(AX)(CX*1), X9
-	MOVOU	-96(AX)(CX*1), X10
-	MOVOU	-80(AX)(CX*1), X11
-	MOVOU	-64(AX)(CX*1), X12
-	MOVOU	-48(AX)(CX*1), X13
-	MOVOU	-32(AX)(CX*1), X14
-	MOVOU	-16(AX)(CX*1), X15
-
-	// xor in seed
-	PXOR	X0, X8
-	PXOR	X1, X9
-	PXOR	X2, X10
-	PXOR	X3, X11
-	PXOR	X4, X12
-	PXOR	X5, X13
-	PXOR	X6, X14
-	PXOR	X7, X15
-
-	// compute number of remaining 128-byte blocks
-	DECQ	CX
-	SHRQ	$7, CX
-
-aesloop:
-	// scramble state
-	AESENC	X8, X8
-	AESENC	X9, X9
-	AESENC	X10, X10
-	AESENC	X11, X11
-	AESENC	X12, X12
-	AESENC	X13, X13
-	AESENC	X14, X14
-	AESENC	X15, X15
-
-	// scramble state, xor in a block
-	MOVOU	(AX), X0
-	MOVOU	16(AX), X1
-	MOVOU	32(AX), X2
-	MOVOU	48(AX), X3
-	AESENC	X0, X8
-	AESENC	X1, X9
-	AESENC	X2, X10
-	AESENC	X3, X11
-	MOVOU	64(AX), X4
-	MOVOU	80(AX), X5
-	MOVOU	96(AX), X6
-	MOVOU	112(AX), X7
-	AESENC	X4, X12
-	AESENC	X5, X13
-	AESENC	X6, X14
-	AESENC	X7, X15
-
-	ADDQ	$128, AX
-	DECQ	CX
-	JNE	aesloop
-
-	// 3 more scrambles to finish
-	AESENC	X8, X8
-	AESENC	X9, X9
-	AESENC	X10, X10
-	AESENC	X11, X11
-	AESENC	X12, X12
-	AESENC	X13, X13
-	AESENC	X14, X14
-	AESENC	X15, X15
-	AESENC	X8, X8
-	AESENC	X9, X9
-	AESENC	X10, X10
-	AESENC	X11, X11
-	AESENC	X12, X12
-	AESENC	X13, X13
-	AESENC	X14, X14
-	AESENC	X15, X15
-	AESENC	X8, X8
-	AESENC	X9, X9
-	AESENC	X10, X10
-	AESENC	X11, X11
-	AESENC	X12, X12
-	AESENC	X13, X13
-	AESENC	X14, X14
-	AESENC	X15, X15
-
-	PXOR	X12, X8
-	PXOR	X13, X9
-	PXOR	X14, X10
-	PXOR	X15, X11
-	PXOR	X10, X8
-	PXOR	X11, X9
-	PXOR	X9, X8
-	// X15 must be zero on return
-	PXOR	X15, X15
-	MOVQ	X8, AX	// return X8
-	RET
-
-// func memhash32(p unsafe.Pointer, h uintptr) uintptr
-// ABIInternal for performance.
-TEXT runtime·memhash32<ABIInternal>(SB),NOSPLIT,$0-24
-	// AX = ptr to data
-	// BX = seed
-	CMPB	runtime·useAeshash(SB), $0
-	JEQ	noaes
-	MOVQ	BX, X0	// X0 = seed
-	PINSRD	$2, (AX), X0	// data
-	AESENC	runtime·aeskeysched+0(SB), X0
-	AESENC	runtime·aeskeysched+16(SB), X0
-	AESENC	runtime·aeskeysched+32(SB), X0
-	MOVQ	X0, AX	// return X0
-	RET
-noaes:
-	JMP	runtime·memhash32Fallback<ABIInternal>(SB)
-
-// func memhash64(p unsafe.Pointer, h uintptr) uintptr
-// ABIInternal for performance.
-TEXT runtime·memhash64<ABIInternal>(SB),NOSPLIT,$0-24
-	// AX = ptr to data
-	// BX = seed
-	CMPB	runtime·useAeshash(SB), $0
-	JEQ	noaes
-	MOVQ	BX, X0	// X0 = seed
-	PINSRQ	$1, (AX), X0	// data
-	AESENC	runtime·aeskeysched+0(SB), X0
-	AESENC	runtime·aeskeysched+16(SB), X0
-	AESENC	runtime·aeskeysched+32(SB), X0
-	MOVQ	X0, AX	// return X0
-	RET
-noaes:
-	JMP	runtime·memhash64Fallback<ABIInternal>(SB)
-
-// simple mask to get rid of data in the high part of the register.
-DATA masks<>+0x00(SB)/8, $0x0000000000000000
-DATA masks<>+0x08(SB)/8, $0x0000000000000000
-DATA masks<>+0x10(SB)/8, $0x00000000000000ff
-DATA masks<>+0x18(SB)/8, $0x0000000000000000
-DATA masks<>+0x20(SB)/8, $0x000000000000ffff
-DATA masks<>+0x28(SB)/8, $0x0000000000000000
-DATA masks<>+0x30(SB)/8, $0x0000000000ffffff
-DATA masks<>+0x38(SB)/8, $0x0000000000000000
-DATA masks<>+0x40(SB)/8, $0x00000000ffffffff
-DATA masks<>+0x48(SB)/8, $0x0000000000000000
-DATA masks<>+0x50(SB)/8, $0x000000ffffffffff
-DATA masks<>+0x58(SB)/8, $0x0000000000000000
-DATA masks<>+0x60(SB)/8, $0x0000ffffffffffff
-DATA masks<>+0x68(SB)/8, $0x0000000000000000
-DATA masks<>+0x70(SB)/8, $0x00ffffffffffffff
-DATA masks<>+0x78(SB)/8, $0x0000000000000000
-DATA masks<>+0x80(SB)/8, $0xffffffffffffffff
-DATA masks<>+0x88(SB)/8, $0x0000000000000000
-DATA masks<>+0x90(SB)/8, $0xffffffffffffffff
-DATA masks<>+0x98(SB)/8, $0x00000000000000ff
-DATA masks<>+0xa0(SB)/8, $0xffffffffffffffff
-DATA masks<>+0xa8(SB)/8, $0x000000000000ffff
-DATA masks<>+0xb0(SB)/8, $0xffffffffffffffff
-DATA masks<>+0xb8(SB)/8, $0x0000000000ffffff
-DATA masks<>+0xc0(SB)/8, $0xffffffffffffffff
-DATA masks<>+0xc8(SB)/8, $0x00000000ffffffff
-DATA masks<>+0xd0(SB)/8, $0xffffffffffffffff
-DATA masks<>+0xd8(SB)/8, $0x000000ffffffffff
-DATA masks<>+0xe0(SB)/8, $0xffffffffffffffff
-DATA masks<>+0xe8(SB)/8, $0x0000ffffffffffff
-DATA masks<>+0xf0(SB)/8, $0xffffffffffffffff
-DATA masks<>+0xf8(SB)/8, $0x00ffffffffffffff
-GLOBL masks<>(SB),RODATA,$256
-
-// func checkASM() bool
-TEXT ·checkASM(SB),NOSPLIT,$0-1
-	// check that masks<>(SB) and shifts<>(SB) are aligned to 16-byte
-	MOVQ	$masks<>(SB), AX
-	MOVQ	$shifts<>(SB), BX
-	ORQ	BX, AX
-	TESTQ	$15, AX
-	SETEQ	ret+0(FP)
-	RET
-
-// these are arguments to pshufb. They move data down from
-// the high bytes of the register to the low bytes of the register.
-// index is how many bytes to move.
-DATA shifts<>+0x00(SB)/8, $0x0000000000000000
-DATA shifts<>+0x08(SB)/8, $0x0000000000000000
-DATA shifts<>+0x10(SB)/8, $0xffffffffffffff0f
-DATA shifts<>+0x18(SB)/8, $0xffffffffffffffff
-DATA shifts<>+0x20(SB)/8, $0xffffffffffff0f0e
-DATA shifts<>+0x28(SB)/8, $0xffffffffffffffff
-DATA shifts<>+0x30(SB)/8, $0xffffffffff0f0e0d
-DATA shifts<>+0x38(SB)/8, $0xffffffffffffffff
-DATA shifts<>+0x40(SB)/8, $0xffffffff0f0e0d0c
-DATA shifts<>+0x48(SB)/8, $0xffffffffffffffff
-DATA shifts<>+0x50(SB)/8, $0xffffff0f0e0d0c0b
-DATA shifts<>+0x58(SB)/8, $0xffffffffffffffff
-DATA shifts<>+0x60(SB)/8, $0xffff0f0e0d0c0b0a
-DATA shifts<>+0x68(SB)/8, $0xffffffffffffffff
-DATA shifts<>+0x70(SB)/8, $0xff0f0e0d0c0b0a09
-DATA shifts<>+0x78(SB)/8, $0xffffffffffffffff
-DATA shifts<>+0x80(SB)/8, $0x0f0e0d0c0b0a0908
-DATA shifts<>+0x88(SB)/8, $0xffffffffffffffff
-DATA shifts<>+0x90(SB)/8, $0x0e0d0c0b0a090807
-DATA shifts<>+0x98(SB)/8, $0xffffffffffffff0f
-DATA shifts<>+0xa0(SB)/8, $0x0d0c0b0a09080706
-DATA shifts<>+0xa8(SB)/8, $0xffffffffffff0f0e
-DATA shifts<>+0xb0(SB)/8, $0x0c0b0a0908070605
-DATA shifts<>+0xb8(SB)/8, $0xffffffffff0f0e0d
-DATA shifts<>+0xc0(SB)/8, $0x0b0a090807060504
-DATA shifts<>+0xc8(SB)/8, $0xffffffff0f0e0d0c
-DATA shifts<>+0xd0(SB)/8, $0x0a09080706050403
-DATA shifts<>+0xd8(SB)/8, $0xffffff0f0e0d0c0b
-DATA shifts<>+0xe0(SB)/8, $0x0908070605040302
-DATA shifts<>+0xe8(SB)/8, $0xffff0f0e0d0c0b0a
-DATA shifts<>+0xf0(SB)/8, $0x0807060504030201
-DATA shifts<>+0xf8(SB)/8, $0xff0f0e0d0c0b0a09
-GLOBL shifts<>(SB),RODATA,$256
-
-TEXT runtime·return0(SB), NOSPLIT, $0
-	MOVL	$0, AX
-	RET
-
-
-// Called from cgo wrappers, this function returns g->m->curg.stack.hi.
-// Must obey the gcc calling convention.
-TEXT _cgo_topofstack(SB),NOSPLIT,$0
-	get_tls(CX)
-	MOVQ	g(CX), AX
-	MOVQ	g_m(AX), AX
-	MOVQ	m_curg(AX), AX
-	MOVQ	(g_stack+stack_hi)(AX), AX
-	RET
-
-// The top-most function running on a goroutine
-// returns to goexit+PCQuantum.
-TEXT runtime·goexit(SB),NOSPLIT|TOPFRAME,$0-0
-	BYTE	$0x90	// NOP
-	CALL	runtime·goexit1(SB)	// does not return
-	// traceback from goexit1 must hit code range of goexit
-	BYTE	$0x90	// NOP
-
-// This is called from .init_array and follows the platform, not Go, ABI.
-TEXT runtime·addmoduledata(SB),NOSPLIT,$0-0
-	PUSHQ	R15 // The access to global variables below implicitly uses R15, which is callee-save
-	MOVQ	runtime·lastmoduledatap(SB), AX
-	MOVQ	DI, moduledata_next(AX)
-	MOVQ	DI, runtime·lastmoduledatap(SB)
-	POPQ	R15
-	RET
-
-// Initialize special registers then jump to sigpanic.
-// This function is injected from the signal handler for panicking
-// signals. It is quite painful to set X15 in the signal context,
-// so we do it here.
-TEXT ·sigpanic0(SB),NOSPLIT,$0-0
-	get_tls(R14)
-	MOVQ	g(R14), R14
-#ifndef GOOS_plan9
-	XORPS	X15, X15
-#endif
-	JMP	·sigpanic<ABIInternal>(SB)
-
-// gcWriteBarrier performs a heap pointer write and informs the GC.
-//
-// gcWriteBarrier does NOT follow the Go ABI. It takes two arguments:
-// - DI is the destination of the write
-// - AX is the value being written at DI
-// It clobbers FLAGS. It does not clobber any general-purpose registers,
-// but may clobber others (e.g., SSE registers).
-// Defined as ABIInternal since it does not use the stack-based Go ABI.
-TEXT runtime·gcWriteBarrier<ABIInternal>(SB),NOSPLIT,$112
-	// Save the registers clobbered by the fast path. This is slightly
-	// faster than having the caller spill these.
-	MOVQ	R12, 96(SP)
-	MOVQ	R13, 104(SP)
-	// TODO: Consider passing g.m.p in as an argument so they can be shared
-	// across a sequence of write barriers.
-	MOVQ	g_m(R14), R13
-	MOVQ	m_p(R13), R13
-	MOVQ	(p_wbBuf+wbBuf_next)(R13), R12
-	// Increment wbBuf.next position.
-	LEAQ	16(R12), R12
-	MOVQ	R12, (p_wbBuf+wbBuf_next)(R13)
-	CMPQ	R12, (p_wbBuf+wbBuf_end)(R13)
-	// Record the write.
-	MOVQ	AX, -16(R12)	// Record value
-	// Note: This turns bad pointer writes into bad
-	// pointer reads, which could be confusing. We could avoid
-	// reading from obviously bad pointers, which would
-	// take care of the vast majority of these. We could
-	// patch this up in the signal handler, or use XCHG to
-	// combine the read and the write.
-	MOVQ	(DI), R13
-	MOVQ	R13, -8(R12)	// Record *slot
-	// Is the buffer full? (flags set in CMPQ above)
-	JEQ	flush
-ret:
-	MOVQ	96(SP), R12
-	MOVQ	104(SP), R13
-	// Do the write.
-	MOVQ	AX, (DI)
-	RET
-
-flush:
-	// Save all general purpose registers since these could be
-	// clobbered by wbBufFlush and were not saved by the caller.
-	// It is possible for wbBufFlush to clobber other registers
-	// (e.g., SSE registers), but the compiler takes care of saving
-	// those in the caller if necessary. This strikes a balance
-	// with registers that are likely to be used.
-	//
-	// We don't have type information for these, but all code under
-	// here is NOSPLIT, so nothing will observe these.
-	//
-	// TODO: We could strike a different balance; e.g., saving X0
-	// and not saving GP registers that are less likely to be used.
-	MOVQ	DI, 0(SP)	// Also first argument to wbBufFlush
-	MOVQ	AX, 8(SP)	// Also second argument to wbBufFlush
-	MOVQ	BX, 16(SP)
-	MOVQ	CX, 24(SP)
-	MOVQ	DX, 32(SP)
-	// DI already saved
-	MOVQ	SI, 40(SP)
-	MOVQ	BP, 48(SP)
-	MOVQ	R8, 56(SP)
-	MOVQ	R9, 64(SP)
-	MOVQ	R10, 72(SP)
-	MOVQ	R11, 80(SP)
-	// R12 already saved
-	// R13 already saved
-	// R14 is g
-	MOVQ	R15, 88(SP)
-
-	// This takes arguments DI and AX
-	CALL	runtime·wbBufFlush(SB)
-
-	MOVQ	0(SP), DI
-	MOVQ	8(SP), AX
-	MOVQ	16(SP), BX
-	MOVQ	24(SP), CX
-	MOVQ	32(SP), DX
-	MOVQ	40(SP), SI
-	MOVQ	48(SP), BP
-	MOVQ	56(SP), R8
-	MOVQ	64(SP), R9
-	MOVQ	72(SP), R10
-	MOVQ	80(SP), R11
-	MOVQ	88(SP), R15
-	JMP	ret
-
-// gcWriteBarrierCX is gcWriteBarrier, but with args in DI and CX.
-// Defined as ABIInternal since it does not use the stable Go ABI.
-TEXT runtime·gcWriteBarrierCX<ABIInternal>(SB),NOSPLIT,$0
-	XCHGQ CX, AX
-	CALL runtime·gcWriteBarrier<ABIInternal>(SB)
-	XCHGQ CX, AX
-	RET
-
-// gcWriteBarrierDX is gcWriteBarrier, but with args in DI and DX.
-// Defined as ABIInternal since it does not use the stable Go ABI.
-TEXT runtime·gcWriteBarrierDX<ABIInternal>(SB),NOSPLIT,$0
-	XCHGQ DX, AX
-	CALL runtime·gcWriteBarrier<ABIInternal>(SB)
-	XCHGQ DX, AX
-	RET
-
-// gcWriteBarrierBX is gcWriteBarrier, but with args in DI and BX.
-// Defined as ABIInternal since it does not use the stable Go ABI.
-TEXT runtime·gcWriteBarrierBX<ABIInternal>(SB),NOSPLIT,$0
-	XCHGQ BX, AX
-	CALL runtime·gcWriteBarrier<ABIInternal>(SB)
-	XCHGQ BX, AX
-	RET
-
-// gcWriteBarrierBP is gcWriteBarrier, but with args in DI and BP.
-// Defined as ABIInternal since it does not use the stable Go ABI.
-TEXT runtime·gcWriteBarrierBP<ABIInternal>(SB),NOSPLIT,$0
-	XCHGQ BP, AX
-	CALL runtime·gcWriteBarrier<ABIInternal>(SB)
-	XCHGQ BP, AX
-	RET
-
-// gcWriteBarrierSI is gcWriteBarrier, but with args in DI and SI.
-// Defined as ABIInternal since it does not use the stable Go ABI.
-TEXT runtime·gcWriteBarrierSI<ABIInternal>(SB),NOSPLIT,$0
-	XCHGQ SI, AX
-	CALL runtime·gcWriteBarrier<ABIInternal>(SB)
-	XCHGQ SI, AX
-	RET
-
-// gcWriteBarrierR8 is gcWriteBarrier, but with args in DI and R8.
-// Defined as ABIInternal since it does not use the stable Go ABI.
-TEXT runtime·gcWriteBarrierR8<ABIInternal>(SB),NOSPLIT,$0
-	XCHGQ R8, AX
-	CALL runtime·gcWriteBarrier<ABIInternal>(SB)
-	XCHGQ R8, AX
-	RET
-
-// gcWriteBarrierR9 is gcWriteBarrier, but with args in DI and R9.
-// Defined as ABIInternal since it does not use the stable Go ABI.
-TEXT runtime·gcWriteBarrierR9<ABIInternal>(SB),NOSPLIT,$0
-	XCHGQ R9, AX
-	CALL runtime·gcWriteBarrier<ABIInternal>(SB)
-	XCHGQ R9, AX
-	RET
-
-DATA	debugCallFrameTooLarge<>+0x00(SB)/20, $"call frame too large"
-GLOBL	debugCallFrameTooLarge<>(SB), RODATA, $20	// Size duplicated below
-
-// debugCallV2 is the entry point for debugger-injected function
-// calls on running goroutines. It informs the runtime that a
-// debug call has been injected and creates a call frame for the
-// debugger to fill in.
-//
-// To inject a function call, a debugger should:
-// 1. Check that the goroutine is in state _Grunning and that
-//    there are at least 256 bytes free on the stack.
-// 2. Push the current PC on the stack (updating SP).
-// 3. Write the desired argument frame size at SP-16 (using the SP
-//    after step 2).
-// 4. Save all machine registers (including flags and XMM reigsters)
-//    so they can be restored later by the debugger.
-// 5. Set the PC to debugCallV2 and resume execution.
-//
-// If the goroutine is in state _Grunnable, then it's not generally
-// safe to inject a call because it may return out via other runtime
-// operations. Instead, the debugger should unwind the stack to find
-// the return to non-runtime code, add a temporary breakpoint there,
-// and inject the call once that breakpoint is hit.
-//
-// If the goroutine is in any other state, it's not safe to inject a call.
-//
-// This function communicates back to the debugger by setting R12 and
-// invoking INT3 to raise a breakpoint signal. See the comments in the
-// implementation for the protocol the debugger is expected to
-// follow. InjectDebugCall in the runtime tests demonstrates this protocol.
-//
-// The debugger must ensure that any pointers passed to the function
-// obey escape analysis requirements. Specifically, it must not pass
-// a stack pointer to an escaping argument. debugCallV2 cannot check
-// this invariant.
-//
-// This is ABIInternal because Go code injects its PC directly into new
-// goroutine stacks.
-TEXT runtime·debugCallV2<ABIInternal>(SB),NOSPLIT,$152-0
-	// Save all registers that may contain pointers so they can be
-	// conservatively scanned.
-	//
-	// We can't do anything that might clobber any of these
-	// registers before this.
-	MOVQ	R15, r15-(14*8+8)(SP)
-	MOVQ	R14, r14-(13*8+8)(SP)
-	MOVQ	R13, r13-(12*8+8)(SP)
-	MOVQ	R12, r12-(11*8+8)(SP)
-	MOVQ	R11, r11-(10*8+8)(SP)
-	MOVQ	R10, r10-(9*8+8)(SP)
-	MOVQ	R9, r9-(8*8+8)(SP)
-	MOVQ	R8, r8-(7*8+8)(SP)
-	MOVQ	DI, di-(6*8+8)(SP)
-	MOVQ	SI, si-(5*8+8)(SP)
-	MOVQ	BP, bp-(4*8+8)(SP)
-	MOVQ	BX, bx-(3*8+8)(SP)
-	MOVQ	DX, dx-(2*8+8)(SP)
-	// Save the frame size before we clobber it. Either of the last
-	// saves could clobber this depending on whether there's a saved BP.
-	MOVQ	frameSize-24(FP), DX	// aka -16(RSP) before prologue
-	MOVQ	CX, cx-(1*8+8)(SP)
-	MOVQ	AX, ax-(0*8+8)(SP)
-
-	// Save the argument frame size.
-	MOVQ	DX, frameSize-128(SP)
-
-	// Perform a safe-point check.
-	MOVQ	retpc-8(FP), AX	// Caller's PC
-	MOVQ	AX, 0(SP)
-	CALL	runtime·debugCallCheck(SB)
-	MOVQ	8(SP), AX
-	TESTQ	AX, AX
-	JZ	good
-	// The safety check failed. Put the reason string at the top
-	// of the stack.
-	MOVQ	AX, 0(SP)
-	MOVQ	16(SP), AX
-	MOVQ	AX, 8(SP)
-	// Set R12 to 8 and invoke INT3. The debugger should get the
-	// reason a call can't be injected from the top of the stack
-	// and resume execution.
-	MOVQ	$8, R12
-	BYTE	$0xcc
-	JMP	restore
-
-good:
-	// Registers are saved and it's safe to make a call.
-	// Open up a call frame, moving the stack if necessary.
-	//
-	// Once the frame is allocated, this will set R12 to 0 and
-	// invoke INT3. The debugger should write the argument
-	// frame for the call at SP, set up argument registers, push
-	// the trapping PC on the stack, set the PC to the function to
-	// call, set RDX to point to the closure (if a closure call),
-	// and resume execution.
-	//
-	// If the function returns, this will set R12 to 1 and invoke
-	// INT3. The debugger can then inspect any return value saved
-	// on the stack at SP and in registers and resume execution again.
-	//
-	// If the function panics, this will set R12 to 2 and invoke INT3.
-	// The interface{} value of the panic will be at SP. The debugger
-	// can inspect the panic value and resume execution again.
-#define DEBUG_CALL_DISPATCH(NAME,MAXSIZE)	\
-	CMPQ	AX, $MAXSIZE;			\
-	JA	5(PC);				\
-	MOVQ	$NAME(SB), AX;			\
-	MOVQ	AX, 0(SP);			\
-	CALL	runtime·debugCallWrap(SB);	\
-	JMP	restore
-
-	MOVQ	frameSize-128(SP), AX
-	DEBUG_CALL_DISPATCH(debugCall32<>, 32)
-	DEBUG_CALL_DISPATCH(debugCall64<>, 64)
-	DEBUG_CALL_DISPATCH(debugCall128<>, 128)
-	DEBUG_CALL_DISPATCH(debugCall256<>, 256)
-	DEBUG_CALL_DISPATCH(debugCall512<>, 512)
-	DEBUG_CALL_DISPATCH(debugCall1024<>, 1024)
-	DEBUG_CALL_DISPATCH(debugCall2048<>, 2048)
-	DEBUG_CALL_DISPATCH(debugCall4096<>, 4096)
-	DEBUG_CALL_DISPATCH(debugCall8192<>, 8192)
-	DEBUG_CALL_DISPATCH(debugCall16384<>, 16384)
-	DEBUG_CALL_DISPATCH(debugCall32768<>, 32768)
-	DEBUG_CALL_DISPATCH(debugCall65536<>, 65536)
-	// The frame size is too large. Report the error.
-	MOVQ	$debugCallFrameTooLarge<>(SB), AX
-	MOVQ	AX, 0(SP)
-	MOVQ	$20, 8(SP) // length of debugCallFrameTooLarge string
-	MOVQ	$8, R12
-	BYTE	$0xcc
-	JMP	restore
-
-restore:
-	// Calls and failures resume here.
-	//
-	// Set R12 to 16 and invoke INT3. The debugger should restore
-	// all registers except RIP and RSP and resume execution.
-	MOVQ	$16, R12
-	BYTE	$0xcc
-	// We must not modify flags after this point.
-
-	// Restore pointer-containing registers, which may have been
-	// modified from the debugger's copy by stack copying.
-	MOVQ	ax-(0*8+8)(SP), AX
-	MOVQ	cx-(1*8+8)(SP), CX
-	MOVQ	dx-(2*8+8)(SP), DX
-	MOVQ	bx-(3*8+8)(SP), BX
-	MOVQ	bp-(4*8+8)(SP), BP
-	MOVQ	si-(5*8+8)(SP), SI
-	MOVQ	di-(6*8+8)(SP), DI
-	MOVQ	r8-(7*8+8)(SP), R8
-	MOVQ	r9-(8*8+8)(SP), R9
-	MOVQ	r10-(9*8+8)(SP), R10
-	MOVQ	r11-(10*8+8)(SP), R11
-	MOVQ	r12-(11*8+8)(SP), R12
-	MOVQ	r13-(12*8+8)(SP), R13
-	MOVQ	r14-(13*8+8)(SP), R14
-	MOVQ	r15-(14*8+8)(SP), R15
-
-	RET
-
-// runtime.debugCallCheck assumes that functions defined with the
-// DEBUG_CALL_FN macro are safe points to inject calls.
-#define DEBUG_CALL_FN(NAME,MAXSIZE)		\
-TEXT NAME(SB),WRAPPER,$MAXSIZE-0;		\
-	NO_LOCAL_POINTERS;			\
-	MOVQ	$0, R12;				\
-	BYTE	$0xcc;				\
-	MOVQ	$1, R12;				\
-	BYTE	$0xcc;				\
-	RET
-DEBUG_CALL_FN(debugCall32<>, 32)
-DEBUG_CALL_FN(debugCall64<>, 64)
-DEBUG_CALL_FN(debugCall128<>, 128)
-DEBUG_CALL_FN(debugCall256<>, 256)
-DEBUG_CALL_FN(debugCall512<>, 512)
-DEBUG_CALL_FN(debugCall1024<>, 1024)
-DEBUG_CALL_FN(debugCall2048<>, 2048)
-DEBUG_CALL_FN(debugCall4096<>, 4096)
-DEBUG_CALL_FN(debugCall8192<>, 8192)
-DEBUG_CALL_FN(debugCall16384<>, 16384)
-DEBUG_CALL_FN(debugCall32768<>, 32768)
-DEBUG_CALL_FN(debugCall65536<>, 65536)
-
-// func debugCallPanicked(val interface{})
-TEXT runtime·debugCallPanicked(SB),NOSPLIT,$16-16
-	// Copy the panic value to the top of stack.
-	MOVQ	val_type+0(FP), AX
-	MOVQ	AX, 0(SP)
-	MOVQ	val_data+8(FP), AX
-	MOVQ	AX, 8(SP)
-	MOVQ	$2, R12
-	BYTE	$0xcc
-	RET
-
-// Note: these functions use a special calling convention to save generated code space.
-// Arguments are passed in registers, but the space for those arguments are allocated
-// in the caller's stack frame. These stubs write the args into that stack space and
-// then tail call to the corresponding runtime handler.
-// The tail call makes these stubs disappear in backtraces.
-// Defined as ABIInternal since they do not use the stack-based Go ABI.
-TEXT runtime·panicIndex<ABIInternal>(SB),NOSPLIT,$0-16
-	MOVQ	CX, BX
-	JMP	runtime·goPanicIndex<ABIInternal>(SB)
-TEXT runtime·panicIndexU<ABIInternal>(SB),NOSPLIT,$0-16
-	MOVQ	CX, BX
-	JMP	runtime·goPanicIndexU<ABIInternal>(SB)
-TEXT runtime·panicSliceAlen<ABIInternal>(SB),NOSPLIT,$0-16
-	MOVQ	CX, AX
-	MOVQ	DX, BX
-	JMP	runtime·goPanicSliceAlen<ABIInternal>(SB)
-TEXT runtime·panicSliceAlenU<ABIInternal>(SB),NOSPLIT,$0-16
-	MOVQ	CX, AX
-	MOVQ	DX, BX
-	JMP	runtime·goPanicSliceAlenU<ABIInternal>(SB)
-TEXT runtime·panicSliceAcap<ABIInternal>(SB),NOSPLIT,$0-16
-	MOVQ	CX, AX
-	MOVQ	DX, BX
-	JMP	runtime·goPanicSliceAcap<ABIInternal>(SB)
-TEXT runtime·panicSliceAcapU<ABIInternal>(SB),NOSPLIT,$0-16
-	MOVQ	CX, AX
-	MOVQ	DX, BX
-	JMP	runtime·goPanicSliceAcapU<ABIInternal>(SB)
-TEXT runtime·panicSliceB<ABIInternal>(SB),NOSPLIT,$0-16
-	MOVQ	CX, BX
-	JMP	runtime·goPanicSliceB<ABIInternal>(SB)
-TEXT runtime·panicSliceBU<ABIInternal>(SB),NOSPLIT,$0-16
-	MOVQ	CX, BX
-	JMP	runtime·goPanicSliceBU<ABIInternal>(SB)
-TEXT runtime·panicSlice3Alen<ABIInternal>(SB),NOSPLIT,$0-16
-	MOVQ	DX, AX
-	JMP	runtime·goPanicSlice3Alen<ABIInternal>(SB)
-TEXT runtime·panicSlice3AlenU<ABIInternal>(SB),NOSPLIT,$0-16
-	MOVQ	DX, AX
-	JMP	runtime·goPanicSlice3AlenU<ABIInternal>(SB)
-TEXT runtime·panicSlice3Acap<ABIInternal>(SB),NOSPLIT,$0-16
-	MOVQ	DX, AX
-	JMP	runtime·goPanicSlice3Acap<ABIInternal>(SB)
-TEXT runtime·panicSlice3AcapU<ABIInternal>(SB),NOSPLIT,$0-16
-	MOVQ	DX, AX
-	JMP	runtime·goPanicSlice3AcapU<ABIInternal>(SB)
-TEXT runtime·panicSlice3B<ABIInternal>(SB),NOSPLIT,$0-16
-	MOVQ	CX, AX
-	MOVQ	DX, BX
-	JMP	runtime·goPanicSlice3B<ABIInternal>(SB)
-TEXT runtime·panicSlice3BU<ABIInternal>(SB),NOSPLIT,$0-16
-	MOVQ	CX, AX
-	MOVQ	DX, BX
-	JMP	runtime·goPanicSlice3BU<ABIInternal>(SB)
-TEXT runtime·panicSlice3C<ABIInternal>(SB),NOSPLIT,$0-16
-	MOVQ	CX, BX
-	JMP	runtime·goPanicSlice3C<ABIInternal>(SB)
-TEXT runtime·panicSlice3CU<ABIInternal>(SB),NOSPLIT,$0-16
-	MOVQ	CX, BX
-	JMP	runtime·goPanicSlice3CU<ABIInternal>(SB)
-TEXT runtime·panicSliceConvert<ABIInternal>(SB),NOSPLIT,$0-16
-	MOVQ	DX, AX
-	JMP	runtime·goPanicSliceConvert<ABIInternal>(SB)
-
-#ifdef GOOS_android
-// Use the free TLS_SLOT_APP slot #2 on Android Q.
-// Earlier androids are set up in gcc_android.c.
-DATA runtime·tls_g+0(SB)/8, $16
-GLOBL runtime·tls_g+0(SB), NOPTR, $8
-#endif
-
-// The compiler and assembler's -spectre=ret mode rewrites
-// all indirect CALL AX / JMP AX instructions to be
-// CALL retpolineAX / JMP retpolineAX.
-// See https://support.google.com/faqs/answer/7625886.
-#define RETPOLINE(reg) \
-	/*   CALL setup */     BYTE $0xE8; BYTE $(2+2); BYTE $0; BYTE $0; BYTE $0;	\
-	/* nospec: */									\
-	/*   PAUSE */           BYTE $0xF3; BYTE $0x90;					\
-	/*   JMP nospec */      BYTE $0xEB; BYTE $-(2+2);				\
-	/* setup: */									\
-	/*   MOVQ AX, 0(SP) */  BYTE $0x48|((reg&8)>>1); BYTE $0x89;			\
-	                        BYTE $0x04|((reg&7)<<3); BYTE $0x24;			\
-	/*   RET */             BYTE $0xC3
-
-TEXT runtime·retpolineAX(SB),NOSPLIT,$0; RETPOLINE(0)
-TEXT runtime·retpolineCX(SB),NOSPLIT,$0; RETPOLINE(1)
-TEXT runtime·retpolineDX(SB),NOSPLIT,$0; RETPOLINE(2)
-TEXT runtime·retpolineBX(SB),NOSPLIT,$0; RETPOLINE(3)
-/* SP is 4, can't happen / magic encodings */
-TEXT runtime·retpolineBP(SB),NOSPLIT,$0; RETPOLINE(5)
-TEXT runtime·retpolineSI(SB),NOSPLIT,$0; RETPOLINE(6)
-TEXT runtime·retpolineDI(SB),NOSPLIT,$0; RETPOLINE(7)
-TEXT runtime·retpolineR8(SB),NOSPLIT,$0; RETPOLINE(8)
-TEXT runtime·retpolineR9(SB),NOSPLIT,$0; RETPOLINE(9)
-TEXT runtime·retpolineR10(SB),NOSPLIT,$0; RETPOLINE(10)
-TEXT runtime·retpolineR11(SB),NOSPLIT,$0; RETPOLINE(11)
-TEXT runtime·retpolineR12(SB),NOSPLIT,$0; RETPOLINE(12)
-TEXT runtime·retpolineR13(SB),NOSPLIT,$0; RETPOLINE(13)
-TEXT runtime·retpolineR14(SB),NOSPLIT,$0; RETPOLINE(14)
-TEXT runtime·retpolineR15(SB),NOSPLIT,$0; RETPOLINE(15)
diff --git a/contrib/go/_std_1.18/src/runtime/cgo/callbacks.go b/contrib/go/_std_1.18/src/runtime/cgo/callbacks.go
deleted file mode 100644
index cd8b795387..0000000000
--- a/contrib/go/_std_1.18/src/runtime/cgo/callbacks.go
+++ /dev/null
@@ -1,106 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgo
-
-import "unsafe"
-
-// These utility functions are available to be called from code
-// compiled with gcc via crosscall2.
-
-// The declaration of crosscall2 is:
-//   void crosscall2(void (*fn)(void *), void *, int);
-//
-// We need to export the symbol crosscall2 in order to support
-// callbacks from shared libraries. This applies regardless of
-// linking mode.
-//
-// Compatibility note: SWIG uses crosscall2 in exactly one situation:
-// to call _cgo_panic using the pattern shown below. We need to keep
-// that pattern working. In particular, crosscall2 actually takes four
-// arguments, but it works to call it with three arguments when
-// calling _cgo_panic.
-//go:cgo_export_static crosscall2
-//go:cgo_export_dynamic crosscall2
-
-// Panic. The argument is converted into a Go string.
-
-// Call like this in code compiled with gcc:
-//   struct { const char *p; } a;
-//   a.p = /* string to pass to panic */;
-//   crosscall2(_cgo_panic, &a, sizeof a);
-//   /* The function call will not return.  */
-
-// TODO: We should export a regular C function to panic, change SWIG
-// to use that instead of the above pattern, and then we can drop
-// backwards-compatibility from crosscall2 and stop exporting it.
-
-//go:linkname _runtime_cgo_panic_internal runtime._cgo_panic_internal
-func _runtime_cgo_panic_internal(p *byte)
-
-//go:linkname _cgo_panic _cgo_panic
-//go:cgo_export_static _cgo_panic
-//go:cgo_export_dynamic _cgo_panic
-func _cgo_panic(a *struct{ cstr *byte }) {
-	_runtime_cgo_panic_internal(a.cstr)
-}
-
-//go:cgo_import_static x_cgo_init
-//go:linkname x_cgo_init x_cgo_init
-//go:linkname _cgo_init _cgo_init
-var x_cgo_init byte
-var _cgo_init = &x_cgo_init
-
-//go:cgo_import_static x_cgo_thread_start
-//go:linkname x_cgo_thread_start x_cgo_thread_start
-//go:linkname _cgo_thread_start _cgo_thread_start
-var x_cgo_thread_start byte
-var _cgo_thread_start = &x_cgo_thread_start
-
-// Creates a new system thread without updating any Go state.
-//
-// This method is invoked during shared library loading to create a new OS
-// thread to perform the runtime initialization. This method is similar to
-// _cgo_sys_thread_start except that it doesn't update any Go state.
-
-//go:cgo_import_static x_cgo_sys_thread_create
-//go:linkname x_cgo_sys_thread_create x_cgo_sys_thread_create
-//go:linkname _cgo_sys_thread_create _cgo_sys_thread_create
-var x_cgo_sys_thread_create byte
-var _cgo_sys_thread_create = &x_cgo_sys_thread_create
-
-// Notifies that the runtime has been initialized.
-//
-// We currently block at every CGO entry point (via _cgo_wait_runtime_init_done)
-// to ensure that the runtime has been initialized before the CGO call is
-// executed. This is necessary for shared libraries where we kickoff runtime
-// initialization in a separate thread and return without waiting for this
-// thread to complete the init.
-
-//go:cgo_import_static x_cgo_notify_runtime_init_done
-//go:linkname x_cgo_notify_runtime_init_done x_cgo_notify_runtime_init_done
-//go:linkname _cgo_notify_runtime_init_done _cgo_notify_runtime_init_done
-var x_cgo_notify_runtime_init_done byte
-var _cgo_notify_runtime_init_done = &x_cgo_notify_runtime_init_done
-
-// Sets the traceback context function. See runtime.SetCgoTraceback.
-
-//go:cgo_import_static x_cgo_set_context_function
-//go:linkname x_cgo_set_context_function x_cgo_set_context_function
-//go:linkname _cgo_set_context_function _cgo_set_context_function
-var x_cgo_set_context_function byte
-var _cgo_set_context_function = &x_cgo_set_context_function
-
-// Calls a libc function to execute background work injected via libc
-// interceptors, such as processing pending signals under the thread
-// sanitizer.
-//
-// Left as a nil pointer if no libc interceptors are expected.
-
-//go:cgo_import_static _cgo_yield
-//go:linkname _cgo_yield _cgo_yield
-var _cgo_yield unsafe.Pointer
-
-//go:cgo_export_static _cgo_topofstack
-//go:cgo_export_dynamic _cgo_topofstack
diff --git a/contrib/go/_std_1.18/src/runtime/cgo/cgo.go b/contrib/go/_std_1.18/src/runtime/cgo/cgo.go
deleted file mode 100644
index 4d2caf6c4f..0000000000
--- a/contrib/go/_std_1.18/src/runtime/cgo/cgo.go
+++ /dev/null
@@ -1,34 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-/*
-Package cgo contains runtime support for code generated
-by the cgo tool.  See the documentation for the cgo command
-for details on using cgo.
-*/
-package cgo
-
-/*
-
-#cgo darwin,!arm64 LDFLAGS: -lpthread
-#cgo darwin,arm64 LDFLAGS: -framework CoreFoundation
-#cgo dragonfly LDFLAGS: -lpthread
-#cgo freebsd LDFLAGS: -lpthread
-#cgo android LDFLAGS: -llog
-#cgo !android,linux LDFLAGS: -lpthread
-#cgo netbsd LDFLAGS: -lpthread
-#cgo openbsd LDFLAGS: -lpthread
-#cgo aix LDFLAGS: -Wl,-berok
-#cgo solaris LDFLAGS: -lxnet
-#cgo illumos LDFLAGS: -lsocket
-
-// Issue 35247.
-#cgo darwin CFLAGS: -Wno-nullability-completeness
-
-#cgo CFLAGS: -Wall -Werror
-
-#cgo solaris CPPFLAGS: -D_POSIX_PTHREAD_SEMANTICS
-
-*/
-import "C"
diff --git a/contrib/go/_std_1.18/src/runtime/cgo/gcc_linux_amd64.c b/contrib/go/_std_1.18/src/runtime/cgo/gcc_linux_amd64.c
deleted file mode 100644
index c25e7e769b..0000000000
--- a/contrib/go/_std_1.18/src/runtime/cgo/gcc_linux_amd64.c
+++ /dev/null
@@ -1,94 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-#include <pthread.h>
-#include <errno.h>
-#include <string.h> // strerror
-#include <signal.h>
-#include <stdlib.h>
-#include "libcgo.h"
-#include "libcgo_unix.h"
-
-static void* threadentry(void*);
-static void (*setg_gcc)(void*);
-
-// This will be set in gcc_android.c for android-specific customization.
-void (*x_cgo_inittls)(void **tlsg, void **tlsbase) __attribute__((common));
-
-void
-x_cgo_init(G *g, void (*setg)(void*), void **tlsg, void **tlsbase)
-{
-	pthread_attr_t *attr;
-	size_t size;
-
-	/* The memory sanitizer distributed with versions of clang
-	   before 3.8 has a bug: if you call mmap before malloc, mmap
-	   may return an address that is later overwritten by the msan
-	   library.  Avoid this problem by forcing a call to malloc
-	   here, before we ever call malloc.
-
-	   This is only required for the memory sanitizer, so it's
-	   unfortunate that we always run it.  It should be possible
-	   to remove this when we no longer care about versions of
-	   clang before 3.8.  The test for this is
-	   misc/cgo/testsanitizers.
-
-	   GCC works hard to eliminate a seemingly unnecessary call to
-	   malloc, so we actually use the memory we allocate.  */
-
-	setg_gcc = setg;
-	attr = (pthread_attr_t*)malloc(sizeof *attr);
-	if (attr == NULL) {
-		fatalf("malloc failed: %s", strerror(errno));
-	}
-	pthread_attr_init(attr);
-	pthread_attr_getstacksize(attr, &size);
-	g->stacklo = (uintptr)&size - size + 4096;
-	pthread_attr_destroy(attr);
-	free(attr);
-
-	if (x_cgo_inittls) {
-		x_cgo_inittls(tlsg, tlsbase);
-	}
-}
-
-
-void
-_cgo_sys_thread_start(ThreadStart *ts)
-{
-	pthread_attr_t attr;
-	sigset_t ign, oset;
-	pthread_t p;
-	size_t size;
-	int err;
-
-	sigfillset(&ign);
-	pthread_sigmask(SIG_SETMASK, &ign, &oset);
-
-	pthread_attr_init(&attr);
-	pthread_attr_getstacksize(&attr, &size);
-	// Leave stacklo=0 and set stackhi=size; mstart will do the rest.
-	ts->g->stackhi = size;
-	err = _cgo_try_pthread_create(&p, &attr, threadentry, ts);
-
-	pthread_sigmask(SIG_SETMASK, &oset, nil);
-
-	if (err != 0) {
-		fatalf("pthread_create failed: %s", strerror(err));
-	}
-}
-
-static void*
-threadentry(void *v)
-{
-	ThreadStart ts;
-
-	ts = *(ThreadStart*)v;
-	_cgo_tsan_acquire();
-	free(v);
-	_cgo_tsan_release();
-
-	crosscall_amd64(ts.fn, setg_gcc, (void*)ts.g);
-	return nil;
-}
diff --git a/contrib/go/_std_1.18/src/runtime/cgo/setenv.go b/contrib/go/_std_1.18/src/runtime/cgo/setenv.go
deleted file mode 100644
index 0f4780a945..0000000000
--- a/contrib/go/_std_1.18/src/runtime/cgo/setenv.go
+++ /dev/null
@@ -1,21 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
-
-package cgo
-
-import _ "unsafe" // for go:linkname
-
-//go:cgo_import_static x_cgo_setenv
-//go:linkname x_cgo_setenv x_cgo_setenv
-//go:linkname _cgo_setenv runtime._cgo_setenv
-var x_cgo_setenv byte
-var _cgo_setenv = &x_cgo_setenv
-
-//go:cgo_import_static x_cgo_unsetenv
-//go:linkname x_cgo_unsetenv x_cgo_unsetenv
-//go:linkname _cgo_unsetenv runtime._cgo_unsetenv
-var x_cgo_unsetenv byte
-var _cgo_unsetenv = &x_cgo_unsetenv
diff --git a/contrib/go/_std_1.18/src/runtime/cgo_mmap.go b/contrib/go/_std_1.18/src/runtime/cgo_mmap.go
deleted file mode 100644
index 0cb25bdcda..0000000000
--- a/contrib/go/_std_1.18/src/runtime/cgo_mmap.go
+++ /dev/null
@@ -1,67 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Support for memory sanitizer. See runtime/cgo/mmap.go.
-
-//go:build (linux && amd64) || (linux && arm64)
-
-package runtime
-
-import "unsafe"
-
-// _cgo_mmap is filled in by runtime/cgo when it is linked into the
-// program, so it is only non-nil when using cgo.
-//go:linkname _cgo_mmap _cgo_mmap
-var _cgo_mmap unsafe.Pointer
-
-// _cgo_munmap is filled in by runtime/cgo when it is linked into the
-// program, so it is only non-nil when using cgo.
-//go:linkname _cgo_munmap _cgo_munmap
-var _cgo_munmap unsafe.Pointer
-
-// mmap is used to route the mmap system call through C code when using cgo, to
-// support sanitizer interceptors. Don't allow stack splits, since this function
-// (used by sysAlloc) is called in a lot of low-level parts of the runtime and
-// callers often assume it won't acquire any locks.
-//go:nosplit
-func mmap(addr unsafe.Pointer, n uintptr, prot, flags, fd int32, off uint32) (unsafe.Pointer, int) {
-	if _cgo_mmap != nil {
-		// Make ret a uintptr so that writing to it in the
-		// function literal does not trigger a write barrier.
-		// A write barrier here could break because of the way
-		// that mmap uses the same value both as a pointer and
-		// an errno value.
-		var ret uintptr
-		systemstack(func() {
-			ret = callCgoMmap(addr, n, prot, flags, fd, off)
-		})
-		if ret < 4096 {
-			return nil, int(ret)
-		}
-		return unsafe.Pointer(ret), 0
-	}
-	return sysMmap(addr, n, prot, flags, fd, off)
-}
-
-func munmap(addr unsafe.Pointer, n uintptr) {
-	if _cgo_munmap != nil {
-		systemstack(func() { callCgoMunmap(addr, n) })
-		return
-	}
-	sysMunmap(addr, n)
-}
-
-// sysMmap calls the mmap system call. It is implemented in assembly.
-func sysMmap(addr unsafe.Pointer, n uintptr, prot, flags, fd int32, off uint32) (p unsafe.Pointer, err int)
-
-// callCgoMmap calls the mmap function in the runtime/cgo package
-// using the GCC calling convention. It is implemented in assembly.
-func callCgoMmap(addr unsafe.Pointer, n uintptr, prot, flags, fd int32, off uint32) uintptr
-
-// sysMunmap calls the munmap system call. It is implemented in assembly.
-func sysMunmap(addr unsafe.Pointer, n uintptr)
-
-// callCgoMunmap calls the munmap function in the runtime/cgo package
-// using the GCC calling convention. It is implemented in assembly.
-func callCgoMunmap(addr unsafe.Pointer, n uintptr)
diff --git a/contrib/go/_std_1.18/src/runtime/cgo_sigaction.go b/contrib/go/_std_1.18/src/runtime/cgo_sigaction.go
deleted file mode 100644
index a2e12f0f0e..0000000000
--- a/contrib/go/_std_1.18/src/runtime/cgo_sigaction.go
+++ /dev/null
@@ -1,92 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Support for sanitizers. See runtime/cgo/sigaction.go.
-
-//go:build (linux && amd64) || (freebsd && amd64) || (linux && arm64) || (linux && ppc64le)
-
-package runtime
-
-import "unsafe"
-
-// _cgo_sigaction is filled in by runtime/cgo when it is linked into the
-// program, so it is only non-nil when using cgo.
-//go:linkname _cgo_sigaction _cgo_sigaction
-var _cgo_sigaction unsafe.Pointer
-
-//go:nosplit
-//go:nowritebarrierrec
-func sigaction(sig uint32, new, old *sigactiont) {
-	// racewalk.go avoids adding sanitizing instrumentation to package runtime,
-	// but we might be calling into instrumented C functions here,
-	// so we need the pointer parameters to be properly marked.
-	//
-	// Mark the input as having been written before the call
-	// and the output as read after.
-	if msanenabled && new != nil {
-		msanwrite(unsafe.Pointer(new), unsafe.Sizeof(*new))
-	}
-	if asanenabled && new != nil {
-		asanwrite(unsafe.Pointer(new), unsafe.Sizeof(*new))
-	}
-	if _cgo_sigaction == nil || inForkedChild {
-		sysSigaction(sig, new, old)
-	} else {
-		// We need to call _cgo_sigaction, which means we need a big enough stack
-		// for C.  To complicate matters, we may be in libpreinit (before the
-		// runtime has been initialized) or in an asynchronous signal handler (with
-		// the current thread in transition between goroutines, or with the g0
-		// system stack already in use).
-
-		var ret int32
-
-		var g *g
-		if mainStarted {
-			g = getg()
-		}
-		sp := uintptr(unsafe.Pointer(&sig))
-		switch {
-		case g == nil:
-			// No g: we're on a C stack or a signal stack.
-			ret = callCgoSigaction(uintptr(sig), new, old)
-		case sp < g.stack.lo || sp >= g.stack.hi:
-			// We're no longer on g's stack, so we must be handling a signal.  It's
-			// possible that we interrupted the thread during a transition between g
-			// and g0, so we should stay on the current stack to avoid corrupting g0.
-			ret = callCgoSigaction(uintptr(sig), new, old)
-		default:
-			// We're running on g's stack, so either we're not in a signal handler or
-			// the signal handler has set the correct g.  If we're on gsignal or g0,
-			// systemstack will make the call directly; otherwise, it will switch to
-			// g0 to ensure we have enough room to call a libc function.
-			//
-			// The function literal that we pass to systemstack is not nosplit, but
-			// that's ok: we'll be running on a fresh, clean system stack so the stack
-			// check will always succeed anyway.
-			systemstack(func() {
-				ret = callCgoSigaction(uintptr(sig), new, old)
-			})
-		}
-
-		const EINVAL = 22
-		if ret == EINVAL {
-			// libc reserves certain signals — normally 32-33 — for pthreads, and
-			// returns EINVAL for sigaction calls on those signals.  If we get EINVAL,
-			// fall back to making the syscall directly.
-			sysSigaction(sig, new, old)
-		}
-	}
-
-	if msanenabled && old != nil {
-		msanread(unsafe.Pointer(old), unsafe.Sizeof(*old))
-	}
-	if asanenabled && old != nil {
-		asanread(unsafe.Pointer(old), unsafe.Sizeof(*old))
-	}
-}
-
-// callCgoSigaction calls the sigaction function in the runtime/cgo package
-// using the GCC calling convention. It is implemented in assembly.
-//go:noescape
-func callCgoSigaction(sig uintptr, new, old *sigactiont) int32
diff --git a/contrib/go/_std_1.18/src/runtime/cgocall.go b/contrib/go/_std_1.18/src/runtime/cgocall.go
deleted file mode 100644
index a0c9560fd0..0000000000
--- a/contrib/go/_std_1.18/src/runtime/cgocall.go
+++ /dev/null
@@ -1,639 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Cgo call and callback support.
-//
-// To call into the C function f from Go, the cgo-generated code calls
-// runtime.cgocall(_cgo_Cfunc_f, frame), where _cgo_Cfunc_f is a
-// gcc-compiled function written by cgo.
-//
-// runtime.cgocall (below) calls entersyscall so as not to block
-// other goroutines or the garbage collector, and then calls
-// runtime.asmcgocall(_cgo_Cfunc_f, frame).
-//
-// runtime.asmcgocall (in asm_$GOARCH.s) switches to the m->g0 stack
-// (assumed to be an operating system-allocated stack, so safe to run
-// gcc-compiled code on) and calls _cgo_Cfunc_f(frame).
-//
-// _cgo_Cfunc_f invokes the actual C function f with arguments
-// taken from the frame structure, records the results in the frame,
-// and returns to runtime.asmcgocall.
-//
-// After it regains control, runtime.asmcgocall switches back to the
-// original g (m->curg)'s stack and returns to runtime.cgocall.
-//
-// After it regains control, runtime.cgocall calls exitsyscall, which blocks
-// until this m can run Go code without violating the $GOMAXPROCS limit,
-// and then unlocks g from m.
-//
-// The above description skipped over the possibility of the gcc-compiled
-// function f calling back into Go. If that happens, we continue down
-// the rabbit hole during the execution of f.
-//
-// To make it possible for gcc-compiled C code to call a Go function p.GoF,
-// cgo writes a gcc-compiled function named GoF (not p.GoF, since gcc doesn't
-// know about packages).  The gcc-compiled C function f calls GoF.
-//
-// GoF initializes "frame", a structure containing all of its
-// arguments and slots for p.GoF's results. It calls
-// crosscall2(_cgoexp_GoF, frame, framesize, ctxt) using the gcc ABI.
-//
-// crosscall2 (in cgo/asm_$GOARCH.s) is a four-argument adapter from
-// the gcc function call ABI to the gc function call ABI. At this
-// point we're in the Go runtime, but we're still running on m.g0's
-// stack and outside the $GOMAXPROCS limit. crosscall2 calls
-// runtime.cgocallback(_cgoexp_GoF, frame, ctxt) using the gc ABI.
-// (crosscall2's framesize argument is no longer used, but there's one
-// case where SWIG calls crosscall2 directly and expects to pass this
-// argument. See _cgo_panic.)
-//
-// runtime.cgocallback (in asm_$GOARCH.s) switches from m.g0's stack
-// to the original g (m.curg)'s stack, on which it calls
-// runtime.cgocallbackg(_cgoexp_GoF, frame, ctxt). As part of the
-// stack switch, runtime.cgocallback saves the current SP as
-// m.g0.sched.sp, so that any use of m.g0's stack during the execution
-// of the callback will be done below the existing stack frames.
-// Before overwriting m.g0.sched.sp, it pushes the old value on the
-// m.g0 stack, so that it can be restored later.
-//
-// runtime.cgocallbackg (below) is now running on a real goroutine
-// stack (not an m.g0 stack).  First it calls runtime.exitsyscall, which will
-// block until the $GOMAXPROCS limit allows running this goroutine.
-// Once exitsyscall has returned, it is safe to do things like call the memory
-// allocator or invoke the Go callback function.  runtime.cgocallbackg
-// first defers a function to unwind m.g0.sched.sp, so that if p.GoF
-// panics, m.g0.sched.sp will be restored to its old value: the m.g0 stack
-// and the m.curg stack will be unwound in lock step.
-// Then it calls _cgoexp_GoF(frame).
-//
-// _cgoexp_GoF, which was generated by cmd/cgo, unpacks the arguments
-// from frame, calls p.GoF, writes the results back to frame, and
-// returns. Now we start unwinding this whole process.
-//
-// runtime.cgocallbackg pops but does not execute the deferred
-// function to unwind m.g0.sched.sp, calls runtime.entersyscall, and
-// returns to runtime.cgocallback.
-//
-// After it regains control, runtime.cgocallback switches back to
-// m.g0's stack (the pointer is still in m.g0.sched.sp), restores the old
-// m.g0.sched.sp value from the stack, and returns to crosscall2.
-//
-// crosscall2 restores the callee-save registers for gcc and returns
-// to GoF, which unpacks any result values and returns to f.
-
-package runtime
-
-import (
-	"internal/goarch"
-	"runtime/internal/atomic"
-	"runtime/internal/sys"
-	"unsafe"
-)
-
-// Addresses collected in a cgo backtrace when crashing.
-// Length must match arg.Max in x_cgo_callers in runtime/cgo/gcc_traceback.c.
-type cgoCallers [32]uintptr
-
-// argset matches runtime/cgo/linux_syscall.c:argset_t
-type argset struct {
-	args   unsafe.Pointer
-	retval uintptr
-}
-
-// wrapper for syscall package to call cgocall for libc (cgo) calls.
-//go:linkname syscall_cgocaller syscall.cgocaller
-//go:nosplit
-//go:uintptrescapes
-func syscall_cgocaller(fn unsafe.Pointer, args ...uintptr) uintptr {
-	as := argset{args: unsafe.Pointer(&args[0])}
-	cgocall(fn, unsafe.Pointer(&as))
-	return as.retval
-}
-
-var ncgocall uint64 // number of cgo calls in total for dead m
-
-// Call from Go to C.
-//
-// This must be nosplit because it's used for syscalls on some
-// platforms. Syscalls may have untyped arguments on the stack, so
-// it's not safe to grow or scan the stack.
-//
-//go:nosplit
-func cgocall(fn, arg unsafe.Pointer) int32 {
-	if !iscgo && GOOS != "solaris" && GOOS != "illumos" && GOOS != "windows" {
-		throw("cgocall unavailable")
-	}
-
-	if fn == nil {
-		throw("cgocall nil")
-	}
-
-	if raceenabled {
-		racereleasemerge(unsafe.Pointer(&racecgosync))
-	}
-
-	mp := getg().m
-	mp.ncgocall++
-	mp.ncgo++
-
-	// Reset traceback.
-	mp.cgoCallers[0] = 0
-
-	// Announce we are entering a system call
-	// so that the scheduler knows to create another
-	// M to run goroutines while we are in the
-	// foreign code.
-	//
-	// The call to asmcgocall is guaranteed not to
-	// grow the stack and does not allocate memory,
-	// so it is safe to call while "in a system call", outside
-	// the $GOMAXPROCS accounting.
-	//
-	// fn may call back into Go code, in which case we'll exit the
-	// "system call", run the Go code (which may grow the stack),
-	// and then re-enter the "system call" reusing the PC and SP
-	// saved by entersyscall here.
-	entersyscall()
-
-	// Tell asynchronous preemption that we're entering external
-	// code. We do this after entersyscall because this may block
-	// and cause an async preemption to fail, but at this point a
-	// sync preemption will succeed (though this is not a matter
-	// of correctness).
-	osPreemptExtEnter(mp)
-
-	mp.incgo = true
-	errno := asmcgocall(fn, arg)
-
-	// Update accounting before exitsyscall because exitsyscall may
-	// reschedule us on to a different M.
-	mp.incgo = false
-	mp.ncgo--
-
-	osPreemptExtExit(mp)
-
-	exitsyscall()
-
-	// Note that raceacquire must be called only after exitsyscall has
-	// wired this M to a P.
-	if raceenabled {
-		raceacquire(unsafe.Pointer(&racecgosync))
-	}
-
-	// From the garbage collector's perspective, time can move
-	// backwards in the sequence above. If there's a callback into
-	// Go code, GC will see this function at the call to
-	// asmcgocall. When the Go call later returns to C, the
-	// syscall PC/SP is rolled back and the GC sees this function
-	// back at the call to entersyscall. Normally, fn and arg
-	// would be live at entersyscall and dead at asmcgocall, so if
-	// time moved backwards, GC would see these arguments as dead
-	// and then live. Prevent these undead arguments from crashing
-	// GC by forcing them to stay live across this time warp.
-	KeepAlive(fn)
-	KeepAlive(arg)
-	KeepAlive(mp)
-
-	return errno
-}
-
-// Call from C back to Go. fn must point to an ABIInternal Go entry-point.
-//go:nosplit
-func cgocallbackg(fn, frame unsafe.Pointer, ctxt uintptr) {
-	gp := getg()
-	if gp != gp.m.curg {
-		println("runtime: bad g in cgocallback")
-		exit(2)
-	}
-
-	// The call from C is on gp.m's g0 stack, so we must ensure
-	// that we stay on that M. We have to do this before calling
-	// exitsyscall, since it would otherwise be free to move us to
-	// a different M. The call to unlockOSThread is in unwindm.
-	lockOSThread()
-
-	checkm := gp.m
-
-	// Save current syscall parameters, so m.syscall can be
-	// used again if callback decide to make syscall.
-	syscall := gp.m.syscall
-
-	// entersyscall saves the caller's SP to allow the GC to trace the Go
-	// stack. However, since we're returning to an earlier stack frame and
-	// need to pair with the entersyscall() call made by cgocall, we must
-	// save syscall* and let reentersyscall restore them.
-	savedsp := unsafe.Pointer(gp.syscallsp)
-	savedpc := gp.syscallpc
-	exitsyscall() // coming out of cgo call
-	gp.m.incgo = false
-
-	osPreemptExtExit(gp.m)
-
-	cgocallbackg1(fn, frame, ctxt) // will call unlockOSThread
-
-	// At this point unlockOSThread has been called.
-	// The following code must not change to a different m.
-	// This is enforced by checking incgo in the schedule function.
-
-	gp.m.incgo = true
-
-	if gp.m != checkm {
-		throw("m changed unexpectedly in cgocallbackg")
-	}
-
-	osPreemptExtEnter(gp.m)
-
-	// going back to cgo call
-	reentersyscall(savedpc, uintptr(savedsp))
-
-	gp.m.syscall = syscall
-}
-
-func cgocallbackg1(fn, frame unsafe.Pointer, ctxt uintptr) {
-	gp := getg()
-
-	// When we return, undo the call to lockOSThread in cgocallbackg.
-	// We must still stay on the same m.
-	defer unlockOSThread()
-
-	if gp.m.needextram || atomic.Load(&extraMWaiters) > 0 {
-		gp.m.needextram = false
-		systemstack(newextram)
-	}
-
-	if ctxt != 0 {
-		s := append(gp.cgoCtxt, ctxt)
-
-		// Now we need to set gp.cgoCtxt = s, but we could get
-		// a SIGPROF signal while manipulating the slice, and
-		// the SIGPROF handler could pick up gp.cgoCtxt while
-		// tracing up the stack.  We need to ensure that the
-		// handler always sees a valid slice, so set the
-		// values in an order such that it always does.
-		p := (*slice)(unsafe.Pointer(&gp.cgoCtxt))
-		atomicstorep(unsafe.Pointer(&p.array), unsafe.Pointer(&s[0]))
-		p.cap = cap(s)
-		p.len = len(s)
-
-		defer func(gp *g) {
-			// Decrease the length of the slice by one, safely.
-			p := (*slice)(unsafe.Pointer(&gp.cgoCtxt))
-			p.len--
-		}(gp)
-	}
-
-	if gp.m.ncgo == 0 {
-		// The C call to Go came from a thread not currently running
-		// any Go. In the case of -buildmode=c-archive or c-shared,
-		// this call may be coming in before package initialization
-		// is complete. Wait until it is.
-		<-main_init_done
-	}
-
-	// Check whether the profiler needs to be turned on or off; this route to
-	// run Go code does not use runtime.execute, so bypasses the check there.
-	hz := sched.profilehz
-	if gp.m.profilehz != hz {
-		setThreadCPUProfiler(hz)
-	}
-
-	// Add entry to defer stack in case of panic.
-	restore := true
-	defer unwindm(&restore)
-
-	if raceenabled {
-		raceacquire(unsafe.Pointer(&racecgosync))
-	}
-
-	// Invoke callback. This function is generated by cmd/cgo and
-	// will unpack the argument frame and call the Go function.
-	var cb func(frame unsafe.Pointer)
-	cbFV := funcval{uintptr(fn)}
-	*(*unsafe.Pointer)(unsafe.Pointer(&cb)) = noescape(unsafe.Pointer(&cbFV))
-	cb(frame)
-
-	if raceenabled {
-		racereleasemerge(unsafe.Pointer(&racecgosync))
-	}
-
-	// Do not unwind m->g0->sched.sp.
-	// Our caller, cgocallback, will do that.
-	restore = false
-}
-
-func unwindm(restore *bool) {
-	if *restore {
-		// Restore sp saved by cgocallback during
-		// unwind of g's stack (see comment at top of file).
-		mp := acquirem()
-		sched := &mp.g0.sched
-		sched.sp = *(*uintptr)(unsafe.Pointer(sched.sp + alignUp(sys.MinFrameSize, sys.StackAlign)))
-
-		// Do the accounting that cgocall will not have a chance to do
-		// during an unwind.
-		//
-		// In the case where a Go call originates from C, ncgo is 0
-		// and there is no matching cgocall to end.
-		if mp.ncgo > 0 {
-			mp.incgo = false
-			mp.ncgo--
-			osPreemptExtExit(mp)
-		}
-
-		releasem(mp)
-	}
-}
-
-// called from assembly
-func badcgocallback() {
-	throw("misaligned stack in cgocallback")
-}
-
-// called from (incomplete) assembly
-func cgounimpl() {
-	throw("cgo not implemented")
-}
-
-var racecgosync uint64 // represents possible synchronization in C code
-
-// Pointer checking for cgo code.
-
-// We want to detect all cases where a program that does not use
-// unsafe makes a cgo call passing a Go pointer to memory that
-// contains a Go pointer. Here a Go pointer is defined as a pointer
-// to memory allocated by the Go runtime. Programs that use unsafe
-// can evade this restriction easily, so we don't try to catch them.
-// The cgo program will rewrite all possibly bad pointer arguments to
-// call cgoCheckPointer, where we can catch cases of a Go pointer
-// pointing to a Go pointer.
-
-// Complicating matters, taking the address of a slice or array
-// element permits the C program to access all elements of the slice
-// or array. In that case we will see a pointer to a single element,
-// but we need to check the entire data structure.
-
-// The cgoCheckPointer call takes additional arguments indicating that
-// it was called on an address expression. An additional argument of
-// true means that it only needs to check a single element. An
-// additional argument of a slice or array means that it needs to
-// check the entire slice/array, but nothing else. Otherwise, the
-// pointer could be anything, and we check the entire heap object,
-// which is conservative but safe.
-
-// When and if we implement a moving garbage collector,
-// cgoCheckPointer will pin the pointer for the duration of the cgo
-// call.  (This is necessary but not sufficient; the cgo program will
-// also have to change to pin Go pointers that cannot point to Go
-// pointers.)
-
-// cgoCheckPointer checks if the argument contains a Go pointer that
-// points to a Go pointer, and panics if it does.
-func cgoCheckPointer(ptr any, arg any) {
-	if debug.cgocheck == 0 {
-		return
-	}
-
-	ep := efaceOf(&ptr)
-	t := ep._type
-
-	top := true
-	if arg != nil && (t.kind&kindMask == kindPtr || t.kind&kindMask == kindUnsafePointer) {
-		p := ep.data
-		if t.kind&kindDirectIface == 0 {
-			p = *(*unsafe.Pointer)(p)
-		}
-		if p == nil || !cgoIsGoPointer(p) {
-			return
-		}
-		aep := efaceOf(&arg)
-		switch aep._type.kind & kindMask {
-		case kindBool:
-			if t.kind&kindMask == kindUnsafePointer {
-				// We don't know the type of the element.
-				break
-			}
-			pt := (*ptrtype)(unsafe.Pointer(t))
-			cgoCheckArg(pt.elem, p, true, false, cgoCheckPointerFail)
-			return
-		case kindSlice:
-			// Check the slice rather than the pointer.
-			ep = aep
-			t = ep._type
-		case kindArray:
-			// Check the array rather than the pointer.
-			// Pass top as false since we have a pointer
-			// to the array.
-			ep = aep
-			t = ep._type
-			top = false
-		default:
-			throw("can't happen")
-		}
-	}
-
-	cgoCheckArg(t, ep.data, t.kind&kindDirectIface == 0, top, cgoCheckPointerFail)
-}
-
-const cgoCheckPointerFail = "cgo argument has Go pointer to Go pointer"
-const cgoResultFail = "cgo result has Go pointer"
-
-// cgoCheckArg is the real work of cgoCheckPointer. The argument p
-// is either a pointer to the value (of type t), or the value itself,
-// depending on indir. The top parameter is whether we are at the top
-// level, where Go pointers are allowed.
-func cgoCheckArg(t *_type, p unsafe.Pointer, indir, top bool, msg string) {
-	if t.ptrdata == 0 || p == nil {
-		// If the type has no pointers there is nothing to do.
-		return
-	}
-
-	switch t.kind & kindMask {
-	default:
-		throw("can't happen")
-	case kindArray:
-		at := (*arraytype)(unsafe.Pointer(t))
-		if !indir {
-			if at.len != 1 {
-				throw("can't happen")
-			}
-			cgoCheckArg(at.elem, p, at.elem.kind&kindDirectIface == 0, top, msg)
-			return
-		}
-		for i := uintptr(0); i < at.len; i++ {
-			cgoCheckArg(at.elem, p, true, top, msg)
-			p = add(p, at.elem.size)
-		}
-	case kindChan, kindMap:
-		// These types contain internal pointers that will
-		// always be allocated in the Go heap. It's never OK
-		// to pass them to C.
-		panic(errorString(msg))
-	case kindFunc:
-		if indir {
-			p = *(*unsafe.Pointer)(p)
-		}
-		if !cgoIsGoPointer(p) {
-			return
-		}
-		panic(errorString(msg))
-	case kindInterface:
-		it := *(**_type)(p)
-		if it == nil {
-			return
-		}
-		// A type known at compile time is OK since it's
-		// constant. A type not known at compile time will be
-		// in the heap and will not be OK.
-		if inheap(uintptr(unsafe.Pointer(it))) {
-			panic(errorString(msg))
-		}
-		p = *(*unsafe.Pointer)(add(p, goarch.PtrSize))
-		if !cgoIsGoPointer(p) {
-			return
-		}
-		if !top {
-			panic(errorString(msg))
-		}
-		cgoCheckArg(it, p, it.kind&kindDirectIface == 0, false, msg)
-	case kindSlice:
-		st := (*slicetype)(unsafe.Pointer(t))
-		s := (*slice)(p)
-		p = s.array
-		if p == nil || !cgoIsGoPointer(p) {
-			return
-		}
-		if !top {
-			panic(errorString(msg))
-		}
-		if st.elem.ptrdata == 0 {
-			return
-		}
-		for i := 0; i < s.cap; i++ {
-			cgoCheckArg(st.elem, p, true, false, msg)
-			p = add(p, st.elem.size)
-		}
-	case kindString:
-		ss := (*stringStruct)(p)
-		if !cgoIsGoPointer(ss.str) {
-			return
-		}
-		if !top {
-			panic(errorString(msg))
-		}
-	case kindStruct:
-		st := (*structtype)(unsafe.Pointer(t))
-		if !indir {
-			if len(st.fields) != 1 {
-				throw("can't happen")
-			}
-			cgoCheckArg(st.fields[0].typ, p, st.fields[0].typ.kind&kindDirectIface == 0, top, msg)
-			return
-		}
-		for _, f := range st.fields {
-			if f.typ.ptrdata == 0 {
-				continue
-			}
-			cgoCheckArg(f.typ, add(p, f.offset()), true, top, msg)
-		}
-	case kindPtr, kindUnsafePointer:
-		if indir {
-			p = *(*unsafe.Pointer)(p)
-			if p == nil {
-				return
-			}
-		}
-
-		if !cgoIsGoPointer(p) {
-			return
-		}
-		if !top {
-			panic(errorString(msg))
-		}
-
-		cgoCheckUnknownPointer(p, msg)
-	}
-}
-
-// cgoCheckUnknownPointer is called for an arbitrary pointer into Go
-// memory. It checks whether that Go memory contains any other
-// pointer into Go memory. If it does, we panic.
-// The return values are unused but useful to see in panic tracebacks.
-func cgoCheckUnknownPointer(p unsafe.Pointer, msg string) (base, i uintptr) {
-	if inheap(uintptr(p)) {
-		b, span, _ := findObject(uintptr(p), 0, 0)
-		base = b
-		if base == 0 {
-			return
-		}
-		hbits := heapBitsForAddr(base)
-		n := span.elemsize
-		for i = uintptr(0); i < n; i += goarch.PtrSize {
-			if !hbits.morePointers() {
-				// No more possible pointers.
-				break
-			}
-			if hbits.isPointer() && cgoIsGoPointer(*(*unsafe.Pointer)(unsafe.Pointer(base + i))) {
-				panic(errorString(msg))
-			}
-			hbits = hbits.next()
-		}
-
-		return
-	}
-
-	for _, datap := range activeModules() {
-		if cgoInRange(p, datap.data, datap.edata) || cgoInRange(p, datap.bss, datap.ebss) {
-			// We have no way to know the size of the object.
-			// We have to assume that it might contain a pointer.
-			panic(errorString(msg))
-		}
-		// In the text or noptr sections, we know that the
-		// pointer does not point to a Go pointer.
-	}
-
-	return
-}
-
-// cgoIsGoPointer reports whether the pointer is a Go pointer--a
-// pointer to Go memory. We only care about Go memory that might
-// contain pointers.
-//go:nosplit
-//go:nowritebarrierrec
-func cgoIsGoPointer(p unsafe.Pointer) bool {
-	if p == nil {
-		return false
-	}
-
-	if inHeapOrStack(uintptr(p)) {
-		return true
-	}
-
-	for _, datap := range activeModules() {
-		if cgoInRange(p, datap.data, datap.edata) || cgoInRange(p, datap.bss, datap.ebss) {
-			return true
-		}
-	}
-
-	return false
-}
-
-// cgoInRange reports whether p is between start and end.
-//go:nosplit
-//go:nowritebarrierrec
-func cgoInRange(p unsafe.Pointer, start, end uintptr) bool {
-	return start <= uintptr(p) && uintptr(p) < end
-}
-
-// cgoCheckResult is called to check the result parameter of an
-// exported Go function. It panics if the result is or contains a Go
-// pointer.
-func cgoCheckResult(val any) {
-	if debug.cgocheck == 0 {
-		return
-	}
-
-	ep := efaceOf(&val)
-	t := ep._type
-	cgoCheckArg(t, ep.data, t.kind&kindDirectIface == 0, false, cgoResultFail)
-}
diff --git a/contrib/go/_std_1.18/src/runtime/cgocheck.go b/contrib/go/_std_1.18/src/runtime/cgocheck.go
deleted file mode 100644
index 3acbadf803..0000000000
--- a/contrib/go/_std_1.18/src/runtime/cgocheck.go
+++ /dev/null
@@ -1,263 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Code to check that pointer writes follow the cgo rules.
-// These functions are invoked via the write barrier when debug.cgocheck > 1.
-
-package runtime
-
-import (
-	"internal/goarch"
-	"unsafe"
-)
-
-const cgoWriteBarrierFail = "Go pointer stored into non-Go memory"
-
-// cgoCheckWriteBarrier is called whenever a pointer is stored into memory.
-// It throws if the program is storing a Go pointer into non-Go memory.
-//
-// This is called from the write barrier, so its entire call tree must
-// be nosplit.
-//
-//go:nosplit
-//go:nowritebarrier
-func cgoCheckWriteBarrier(dst *uintptr, src uintptr) {
-	if !cgoIsGoPointer(unsafe.Pointer(src)) {
-		return
-	}
-	if cgoIsGoPointer(unsafe.Pointer(dst)) {
-		return
-	}
-
-	// If we are running on the system stack then dst might be an
-	// address on the stack, which is OK.
-	g := getg()
-	if g == g.m.g0 || g == g.m.gsignal {
-		return
-	}
-
-	// Allocating memory can write to various mfixalloc structs
-	// that look like they are non-Go memory.
-	if g.m.mallocing != 0 {
-		return
-	}
-
-	// It's OK if writing to memory allocated by persistentalloc.
-	// Do this check last because it is more expensive and rarely true.
-	// If it is false the expense doesn't matter since we are crashing.
-	if inPersistentAlloc(uintptr(unsafe.Pointer(dst))) {
-		return
-	}
-
-	systemstack(func() {
-		println("write of Go pointer", hex(src), "to non-Go memory", hex(uintptr(unsafe.Pointer(dst))))
-		throw(cgoWriteBarrierFail)
-	})
-}
-
-// cgoCheckMemmove is called when moving a block of memory.
-// dst and src point off bytes into the value to copy.
-// size is the number of bytes to copy.
-// It throws if the program is copying a block that contains a Go pointer
-// into non-Go memory.
-//go:nosplit
-//go:nowritebarrier
-func cgoCheckMemmove(typ *_type, dst, src unsafe.Pointer, off, size uintptr) {
-	if typ.ptrdata == 0 {
-		return
-	}
-	if !cgoIsGoPointer(src) {
-		return
-	}
-	if cgoIsGoPointer(dst) {
-		return
-	}
-	cgoCheckTypedBlock(typ, src, off, size)
-}
-
-// cgoCheckSliceCopy is called when copying n elements of a slice.
-// src and dst are pointers to the first element of the slice.
-// typ is the element type of the slice.
-// It throws if the program is copying slice elements that contain Go pointers
-// into non-Go memory.
-//go:nosplit
-//go:nowritebarrier
-func cgoCheckSliceCopy(typ *_type, dst, src unsafe.Pointer, n int) {
-	if typ.ptrdata == 0 {
-		return
-	}
-	if !cgoIsGoPointer(src) {
-		return
-	}
-	if cgoIsGoPointer(dst) {
-		return
-	}
-	p := src
-	for i := 0; i < n; i++ {
-		cgoCheckTypedBlock(typ, p, 0, typ.size)
-		p = add(p, typ.size)
-	}
-}
-
-// cgoCheckTypedBlock checks the block of memory at src, for up to size bytes,
-// and throws if it finds a Go pointer. The type of the memory is typ,
-// and src is off bytes into that type.
-//go:nosplit
-//go:nowritebarrier
-func cgoCheckTypedBlock(typ *_type, src unsafe.Pointer, off, size uintptr) {
-	// Anything past typ.ptrdata is not a pointer.
-	if typ.ptrdata <= off {
-		return
-	}
-	if ptrdataSize := typ.ptrdata - off; size > ptrdataSize {
-		size = ptrdataSize
-	}
-
-	if typ.kind&kindGCProg == 0 {
-		cgoCheckBits(src, typ.gcdata, off, size)
-		return
-	}
-
-	// The type has a GC program. Try to find GC bits somewhere else.
-	for _, datap := range activeModules() {
-		if cgoInRange(src, datap.data, datap.edata) {
-			doff := uintptr(src) - datap.data
-			cgoCheckBits(add(src, -doff), datap.gcdatamask.bytedata, off+doff, size)
-			return
-		}
-		if cgoInRange(src, datap.bss, datap.ebss) {
-			boff := uintptr(src) - datap.bss
-			cgoCheckBits(add(src, -boff), datap.gcbssmask.bytedata, off+boff, size)
-			return
-		}
-	}
-
-	s := spanOfUnchecked(uintptr(src))
-	if s.state.get() == mSpanManual {
-		// There are no heap bits for value stored on the stack.
-		// For a channel receive src might be on the stack of some
-		// other goroutine, so we can't unwind the stack even if
-		// we wanted to.
-		// We can't expand the GC program without extra storage
-		// space we can't easily get.
-		// Fortunately we have the type information.
-		systemstack(func() {
-			cgoCheckUsingType(typ, src, off, size)
-		})
-		return
-	}
-
-	// src must be in the regular heap.
-
-	hbits := heapBitsForAddr(uintptr(src))
-	for i := uintptr(0); i < off+size; i += goarch.PtrSize {
-		bits := hbits.bits()
-		if i >= off && bits&bitPointer != 0 {
-			v := *(*unsafe.Pointer)(add(src, i))
-			if cgoIsGoPointer(v) {
-				throw(cgoWriteBarrierFail)
-			}
-		}
-		hbits = hbits.next()
-	}
-}
-
-// cgoCheckBits checks the block of memory at src, for up to size
-// bytes, and throws if it finds a Go pointer. The gcbits mark each
-// pointer value. The src pointer is off bytes into the gcbits.
-//go:nosplit
-//go:nowritebarrier
-func cgoCheckBits(src unsafe.Pointer, gcbits *byte, off, size uintptr) {
-	skipMask := off / goarch.PtrSize / 8
-	skipBytes := skipMask * goarch.PtrSize * 8
-	ptrmask := addb(gcbits, skipMask)
-	src = add(src, skipBytes)
-	off -= skipBytes
-	size += off
-	var bits uint32
-	for i := uintptr(0); i < size; i += goarch.PtrSize {
-		if i&(goarch.PtrSize*8-1) == 0 {
-			bits = uint32(*ptrmask)
-			ptrmask = addb(ptrmask, 1)
-		} else {
-			bits >>= 1
-		}
-		if off > 0 {
-			off -= goarch.PtrSize
-		} else {
-			if bits&1 != 0 {
-				v := *(*unsafe.Pointer)(add(src, i))
-				if cgoIsGoPointer(v) {
-					throw(cgoWriteBarrierFail)
-				}
-			}
-		}
-	}
-}
-
-// cgoCheckUsingType is like cgoCheckTypedBlock, but is a last ditch
-// fall back to look for pointers in src using the type information.
-// We only use this when looking at a value on the stack when the type
-// uses a GC program, because otherwise it's more efficient to use the
-// GC bits. This is called on the system stack.
-//go:nowritebarrier
-//go:systemstack
-func cgoCheckUsingType(typ *_type, src unsafe.Pointer, off, size uintptr) {
-	if typ.ptrdata == 0 {
-		return
-	}
-
-	// Anything past typ.ptrdata is not a pointer.
-	if typ.ptrdata <= off {
-		return
-	}
-	if ptrdataSize := typ.ptrdata - off; size > ptrdataSize {
-		size = ptrdataSize
-	}
-
-	if typ.kind&kindGCProg == 0 {
-		cgoCheckBits(src, typ.gcdata, off, size)
-		return
-	}
-	switch typ.kind & kindMask {
-	default:
-		throw("can't happen")
-	case kindArray:
-		at := (*arraytype)(unsafe.Pointer(typ))
-		for i := uintptr(0); i < at.len; i++ {
-			if off < at.elem.size {
-				cgoCheckUsingType(at.elem, src, off, size)
-			}
-			src = add(src, at.elem.size)
-			skipped := off
-			if skipped > at.elem.size {
-				skipped = at.elem.size
-			}
-			checked := at.elem.size - skipped
-			off -= skipped
-			if size <= checked {
-				return
-			}
-			size -= checked
-		}
-	case kindStruct:
-		st := (*structtype)(unsafe.Pointer(typ))
-		for _, f := range st.fields {
-			if off < f.typ.size {
-				cgoCheckUsingType(f.typ, src, off, size)
-			}
-			src = add(src, f.typ.size)
-			skipped := off
-			if skipped > f.typ.size {
-				skipped = f.typ.size
-			}
-			checked := f.typ.size - skipped
-			off -= skipped
-			if size <= checked {
-				return
-			}
-			size -= checked
-		}
-	}
-}
diff --git a/contrib/go/_std_1.18/src/runtime/chan.go b/contrib/go/_std_1.18/src/runtime/chan.go
deleted file mode 100644
index 3cdb5dce11..0000000000
--- a/contrib/go/_std_1.18/src/runtime/chan.go
+++ /dev/null
@@ -1,846 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-// This file contains the implementation of Go channels.
-
-// Invariants:
-//  At least one of c.sendq and c.recvq is empty,
-//  except for the case of an unbuffered channel with a single goroutine
-//  blocked on it for both sending and receiving using a select statement,
-//  in which case the length of c.sendq and c.recvq is limited only by the
-//  size of the select statement.
-//
-// For buffered channels, also:
-//  c.qcount > 0 implies that c.recvq is empty.
-//  c.qcount < c.dataqsiz implies that c.sendq is empty.
-
-import (
-	"internal/abi"
-	"runtime/internal/atomic"
-	"runtime/internal/math"
-	"unsafe"
-)
-
-const (
-	maxAlign  = 8
-	hchanSize = unsafe.Sizeof(hchan{}) + uintptr(-int(unsafe.Sizeof(hchan{}))&(maxAlign-1))
-	debugChan = false
-)
-
-type hchan struct {
-	qcount   uint           // total data in the queue
-	dataqsiz uint           // size of the circular queue
-	buf      unsafe.Pointer // points to an array of dataqsiz elements
-	elemsize uint16
-	closed   uint32
-	elemtype *_type // element type
-	sendx    uint   // send index
-	recvx    uint   // receive index
-	recvq    waitq  // list of recv waiters
-	sendq    waitq  // list of send waiters
-
-	// lock protects all fields in hchan, as well as several
-	// fields in sudogs blocked on this channel.
-	//
-	// Do not change another G's status while holding this lock
-	// (in particular, do not ready a G), as this can deadlock
-	// with stack shrinking.
-	lock mutex
-}
-
-type waitq struct {
-	first *sudog
-	last  *sudog
-}
-
-//go:linkname reflect_makechan reflect.makechan
-func reflect_makechan(t *chantype, size int) *hchan {
-	return makechan(t, size)
-}
-
-func makechan64(t *chantype, size int64) *hchan {
-	if int64(int(size)) != size {
-		panic(plainError("makechan: size out of range"))
-	}
-
-	return makechan(t, int(size))
-}
-
-func makechan(t *chantype, size int) *hchan {
-	elem := t.elem
-
-	// compiler checks this but be safe.
-	if elem.size >= 1<<16 {
-		throw("makechan: invalid channel element type")
-	}
-	if hchanSize%maxAlign != 0 || elem.align > maxAlign {
-		throw("makechan: bad alignment")
-	}
-
-	mem, overflow := math.MulUintptr(elem.size, uintptr(size))
-	if overflow || mem > maxAlloc-hchanSize || size < 0 {
-		panic(plainError("makechan: size out of range"))
-	}
-
-	// Hchan does not contain pointers interesting for GC when elements stored in buf do not contain pointers.
-	// buf points into the same allocation, elemtype is persistent.
-	// SudoG's are referenced from their owning thread so they can't be collected.
-	// TODO(dvyukov,rlh): Rethink when collector can move allocated objects.
-	var c *hchan
-	switch {
-	case mem == 0:
-		// Queue or element size is zero.
-		c = (*hchan)(mallocgc(hchanSize, nil, true))
-		// Race detector uses this location for synchronization.
-		c.buf = c.raceaddr()
-	case elem.ptrdata == 0:
-		// Elements do not contain pointers.
-		// Allocate hchan and buf in one call.
-		c = (*hchan)(mallocgc(hchanSize+mem, nil, true))
-		c.buf = add(unsafe.Pointer(c), hchanSize)
-	default:
-		// Elements contain pointers.
-		c = new(hchan)
-		c.buf = mallocgc(mem, elem, true)
-	}
-
-	c.elemsize = uint16(elem.size)
-	c.elemtype = elem
-	c.dataqsiz = uint(size)
-	lockInit(&c.lock, lockRankHchan)
-
-	if debugChan {
-		print("makechan: chan=", c, "; elemsize=", elem.size, "; dataqsiz=", size, "\n")
-	}
-	return c
-}
-
-// chanbuf(c, i) is pointer to the i'th slot in the buffer.
-func chanbuf(c *hchan, i uint) unsafe.Pointer {
-	return add(c.buf, uintptr(i)*uintptr(c.elemsize))
-}
-
-// full reports whether a send on c would block (that is, the channel is full).
-// It uses a single word-sized read of mutable state, so although
-// the answer is instantaneously true, the correct answer may have changed
-// by the time the calling function receives the return value.
-func full(c *hchan) bool {
-	// c.dataqsiz is immutable (never written after the channel is created)
-	// so it is safe to read at any time during channel operation.
-	if c.dataqsiz == 0 {
-		// Assumes that a pointer read is relaxed-atomic.
-		return c.recvq.first == nil
-	}
-	// Assumes that a uint read is relaxed-atomic.
-	return c.qcount == c.dataqsiz
-}
-
-// entry point for c <- x from compiled code
-//go:nosplit
-func chansend1(c *hchan, elem unsafe.Pointer) {
-	chansend(c, elem, true, getcallerpc())
-}
-
-/*
- * generic single channel send/recv
- * If block is not nil,
- * then the protocol will not
- * sleep but return if it could
- * not complete.
- *
- * sleep can wake up with g.param == nil
- * when a channel involved in the sleep has
- * been closed.  it is easiest to loop and re-run
- * the operation; we'll see that it's now closed.
- */
-func chansend(c *hchan, ep unsafe.Pointer, block bool, callerpc uintptr) bool {
-	if c == nil {
-		if !block {
-			return false
-		}
-		gopark(nil, nil, waitReasonChanSendNilChan, traceEvGoStop, 2)
-		throw("unreachable")
-	}
-
-	if debugChan {
-		print("chansend: chan=", c, "\n")
-	}
-
-	if raceenabled {
-		racereadpc(c.raceaddr(), callerpc, abi.FuncPCABIInternal(chansend))
-	}
-
-	// Fast path: check for failed non-blocking operation without acquiring the lock.
-	//
-	// After observing that the channel is not closed, we observe that the channel is
-	// not ready for sending. Each of these observations is a single word-sized read
-	// (first c.closed and second full()).
-	// Because a closed channel cannot transition from 'ready for sending' to
-	// 'not ready for sending', even if the channel is closed between the two observations,
-	// they imply a moment between the two when the channel was both not yet closed
-	// and not ready for sending. We behave as if we observed the channel at that moment,
-	// and report that the send cannot proceed.
-	//
-	// It is okay if the reads are reordered here: if we observe that the channel is not
-	// ready for sending and then observe that it is not closed, that implies that the
-	// channel wasn't closed during the first observation. However, nothing here
-	// guarantees forward progress. We rely on the side effects of lock release in
-	// chanrecv() and closechan() to update this thread's view of c.closed and full().
-	if !block && c.closed == 0 && full(c) {
-		return false
-	}
-
-	var t0 int64
-	if blockprofilerate > 0 {
-		t0 = cputicks()
-	}
-
-	lock(&c.lock)
-
-	if c.closed != 0 {
-		unlock(&c.lock)
-		panic(plainError("send on closed channel"))
-	}
-
-	if sg := c.recvq.dequeue(); sg != nil {
-		// Found a waiting receiver. We pass the value we want to send
-		// directly to the receiver, bypassing the channel buffer (if any).
-		send(c, sg, ep, func() { unlock(&c.lock) }, 3)
-		return true
-	}
-
-	if c.qcount < c.dataqsiz {
-		// Space is available in the channel buffer. Enqueue the element to send.
-		qp := chanbuf(c, c.sendx)
-		if raceenabled {
-			racenotify(c, c.sendx, nil)
-		}
-		typedmemmove(c.elemtype, qp, ep)
-		c.sendx++
-		if c.sendx == c.dataqsiz {
-			c.sendx = 0
-		}
-		c.qcount++
-		unlock(&c.lock)
-		return true
-	}
-
-	if !block {
-		unlock(&c.lock)
-		return false
-	}
-
-	// Block on the channel. Some receiver will complete our operation for us.
-	gp := getg()
-	mysg := acquireSudog()
-	mysg.releasetime = 0
-	if t0 != 0 {
-		mysg.releasetime = -1
-	}
-	// No stack splits between assigning elem and enqueuing mysg
-	// on gp.waiting where copystack can find it.
-	mysg.elem = ep
-	mysg.waitlink = nil
-	mysg.g = gp
-	mysg.isSelect = false
-	mysg.c = c
-	gp.waiting = mysg
-	gp.param = nil
-	c.sendq.enqueue(mysg)
-	// Signal to anyone trying to shrink our stack that we're about
-	// to park on a channel. The window between when this G's status
-	// changes and when we set gp.activeStackChans is not safe for
-	// stack shrinking.
-	atomic.Store8(&gp.parkingOnChan, 1)
-	gopark(chanparkcommit, unsafe.Pointer(&c.lock), waitReasonChanSend, traceEvGoBlockSend, 2)
-	// Ensure the value being sent is kept alive until the
-	// receiver copies it out. The sudog has a pointer to the
-	// stack object, but sudogs aren't considered as roots of the
-	// stack tracer.
-	KeepAlive(ep)
-
-	// someone woke us up.
-	if mysg != gp.waiting {
-		throw("G waiting list is corrupted")
-	}
-	gp.waiting = nil
-	gp.activeStackChans = false
-	closed := !mysg.success
-	gp.param = nil
-	if mysg.releasetime > 0 {
-		blockevent(mysg.releasetime-t0, 2)
-	}
-	mysg.c = nil
-	releaseSudog(mysg)
-	if closed {
-		if c.closed == 0 {
-			throw("chansend: spurious wakeup")
-		}
-		panic(plainError("send on closed channel"))
-	}
-	return true
-}
-
-// send processes a send operation on an empty channel c.
-// The value ep sent by the sender is copied to the receiver sg.
-// The receiver is then woken up to go on its merry way.
-// Channel c must be empty and locked.  send unlocks c with unlockf.
-// sg must already be dequeued from c.
-// ep must be non-nil and point to the heap or the caller's stack.
-func send(c *hchan, sg *sudog, ep unsafe.Pointer, unlockf func(), skip int) {
-	if raceenabled {
-		if c.dataqsiz == 0 {
-			racesync(c, sg)
-		} else {
-			// Pretend we go through the buffer, even though
-			// we copy directly. Note that we need to increment
-			// the head/tail locations only when raceenabled.
-			racenotify(c, c.recvx, nil)
-			racenotify(c, c.recvx, sg)
-			c.recvx++
-			if c.recvx == c.dataqsiz {
-				c.recvx = 0
-			}
-			c.sendx = c.recvx // c.sendx = (c.sendx+1) % c.dataqsiz
-		}
-	}
-	if sg.elem != nil {
-		sendDirect(c.elemtype, sg, ep)
-		sg.elem = nil
-	}
-	gp := sg.g
-	unlockf()
-	gp.param = unsafe.Pointer(sg)
-	sg.success = true
-	if sg.releasetime != 0 {
-		sg.releasetime = cputicks()
-	}
-	goready(gp, skip+1)
-}
-
-// Sends and receives on unbuffered or empty-buffered channels are the
-// only operations where one running goroutine writes to the stack of
-// another running goroutine. The GC assumes that stack writes only
-// happen when the goroutine is running and are only done by that
-// goroutine. Using a write barrier is sufficient to make up for
-// violating that assumption, but the write barrier has to work.
-// typedmemmove will call bulkBarrierPreWrite, but the target bytes
-// are not in the heap, so that will not help. We arrange to call
-// memmove and typeBitsBulkBarrier instead.
-
-func sendDirect(t *_type, sg *sudog, src unsafe.Pointer) {
-	// src is on our stack, dst is a slot on another stack.
-
-	// Once we read sg.elem out of sg, it will no longer
-	// be updated if the destination's stack gets copied (shrunk).
-	// So make sure that no preemption points can happen between read & use.
-	dst := sg.elem
-	typeBitsBulkBarrier(t, uintptr(dst), uintptr(src), t.size)
-	// No need for cgo write barrier checks because dst is always
-	// Go memory.
-	memmove(dst, src, t.size)
-}
-
-func recvDirect(t *_type, sg *sudog, dst unsafe.Pointer) {
-	// dst is on our stack or the heap, src is on another stack.
-	// The channel is locked, so src will not move during this
-	// operation.
-	src := sg.elem
-	typeBitsBulkBarrier(t, uintptr(dst), uintptr(src), t.size)
-	memmove(dst, src, t.size)
-}
-
-func closechan(c *hchan) {
-	if c == nil {
-		panic(plainError("close of nil channel"))
-	}
-
-	lock(&c.lock)
-	if c.closed != 0 {
-		unlock(&c.lock)
-		panic(plainError("close of closed channel"))
-	}
-
-	if raceenabled {
-		callerpc := getcallerpc()
-		racewritepc(c.raceaddr(), callerpc, abi.FuncPCABIInternal(closechan))
-		racerelease(c.raceaddr())
-	}
-
-	c.closed = 1
-
-	var glist gList
-
-	// release all readers
-	for {
-		sg := c.recvq.dequeue()
-		if sg == nil {
-			break
-		}
-		if sg.elem != nil {
-			typedmemclr(c.elemtype, sg.elem)
-			sg.elem = nil
-		}
-		if sg.releasetime != 0 {
-			sg.releasetime = cputicks()
-		}
-		gp := sg.g
-		gp.param = unsafe.Pointer(sg)
-		sg.success = false
-		if raceenabled {
-			raceacquireg(gp, c.raceaddr())
-		}
-		glist.push(gp)
-	}
-
-	// release all writers (they will panic)
-	for {
-		sg := c.sendq.dequeue()
-		if sg == nil {
-			break
-		}
-		sg.elem = nil
-		if sg.releasetime != 0 {
-			sg.releasetime = cputicks()
-		}
-		gp := sg.g
-		gp.param = unsafe.Pointer(sg)
-		sg.success = false
-		if raceenabled {
-			raceacquireg(gp, c.raceaddr())
-		}
-		glist.push(gp)
-	}
-	unlock(&c.lock)
-
-	// Ready all Gs now that we've dropped the channel lock.
-	for !glist.empty() {
-		gp := glist.pop()
-		gp.schedlink = 0
-		goready(gp, 3)
-	}
-}
-
-// empty reports whether a read from c would block (that is, the channel is
-// empty).  It uses a single atomic read of mutable state.
-func empty(c *hchan) bool {
-	// c.dataqsiz is immutable.
-	if c.dataqsiz == 0 {
-		return atomic.Loadp(unsafe.Pointer(&c.sendq.first)) == nil
-	}
-	return atomic.Loaduint(&c.qcount) == 0
-}
-
-// entry points for <- c from compiled code
-//go:nosplit
-func chanrecv1(c *hchan, elem unsafe.Pointer) {
-	chanrecv(c, elem, true)
-}
-
-//go:nosplit
-func chanrecv2(c *hchan, elem unsafe.Pointer) (received bool) {
-	_, received = chanrecv(c, elem, true)
-	return
-}
-
-// chanrecv receives on channel c and writes the received data to ep.
-// ep may be nil, in which case received data is ignored.
-// If block == false and no elements are available, returns (false, false).
-// Otherwise, if c is closed, zeros *ep and returns (true, false).
-// Otherwise, fills in *ep with an element and returns (true, true).
-// A non-nil ep must point to the heap or the caller's stack.
-func chanrecv(c *hchan, ep unsafe.Pointer, block bool) (selected, received bool) {
-	// raceenabled: don't need to check ep, as it is always on the stack
-	// or is new memory allocated by reflect.
-
-	if debugChan {
-		print("chanrecv: chan=", c, "\n")
-	}
-
-	if c == nil {
-		if !block {
-			return
-		}
-		gopark(nil, nil, waitReasonChanReceiveNilChan, traceEvGoStop, 2)
-		throw("unreachable")
-	}
-
-	// Fast path: check for failed non-blocking operation without acquiring the lock.
-	if !block && empty(c) {
-		// After observing that the channel is not ready for receiving, we observe whether the
-		// channel is closed.
-		//
-		// Reordering of these checks could lead to incorrect behavior when racing with a close.
-		// For example, if the channel was open and not empty, was closed, and then drained,
-		// reordered reads could incorrectly indicate "open and empty". To prevent reordering,
-		// we use atomic loads for both checks, and rely on emptying and closing to happen in
-		// separate critical sections under the same lock.  This assumption fails when closing
-		// an unbuffered channel with a blocked send, but that is an error condition anyway.
-		if atomic.Load(&c.closed) == 0 {
-			// Because a channel cannot be reopened, the later observation of the channel
-			// being not closed implies that it was also not closed at the moment of the
-			// first observation. We behave as if we observed the channel at that moment
-			// and report that the receive cannot proceed.
-			return
-		}
-		// The channel is irreversibly closed. Re-check whether the channel has any pending data
-		// to receive, which could have arrived between the empty and closed checks above.
-		// Sequential consistency is also required here, when racing with such a send.
-		if empty(c) {
-			// The channel is irreversibly closed and empty.
-			if raceenabled {
-				raceacquire(c.raceaddr())
-			}
-			if ep != nil {
-				typedmemclr(c.elemtype, ep)
-			}
-			return true, false
-		}
-	}
-
-	var t0 int64
-	if blockprofilerate > 0 {
-		t0 = cputicks()
-	}
-
-	lock(&c.lock)
-
-	if c.closed != 0 && c.qcount == 0 {
-		if raceenabled {
-			raceacquire(c.raceaddr())
-		}
-		unlock(&c.lock)
-		if ep != nil {
-			typedmemclr(c.elemtype, ep)
-		}
-		return true, false
-	}
-
-	if sg := c.sendq.dequeue(); sg != nil {
-		// Found a waiting sender. If buffer is size 0, receive value
-		// directly from sender. Otherwise, receive from head of queue
-		// and add sender's value to the tail of the queue (both map to
-		// the same buffer slot because the queue is full).
-		recv(c, sg, ep, func() { unlock(&c.lock) }, 3)
-		return true, true
-	}
-
-	if c.qcount > 0 {
-		// Receive directly from queue
-		qp := chanbuf(c, c.recvx)
-		if raceenabled {
-			racenotify(c, c.recvx, nil)
-		}
-		if ep != nil {
-			typedmemmove(c.elemtype, ep, qp)
-		}
-		typedmemclr(c.elemtype, qp)
-		c.recvx++
-		if c.recvx == c.dataqsiz {
-			c.recvx = 0
-		}
-		c.qcount--
-		unlock(&c.lock)
-		return true, true
-	}
-
-	if !block {
-		unlock(&c.lock)
-		return false, false
-	}
-
-	// no sender available: block on this channel.
-	gp := getg()
-	mysg := acquireSudog()
-	mysg.releasetime = 0
-	if t0 != 0 {
-		mysg.releasetime = -1
-	}
-	// No stack splits between assigning elem and enqueuing mysg
-	// on gp.waiting where copystack can find it.
-	mysg.elem = ep
-	mysg.waitlink = nil
-	gp.waiting = mysg
-	mysg.g = gp
-	mysg.isSelect = false
-	mysg.c = c
-	gp.param = nil
-	c.recvq.enqueue(mysg)
-	// Signal to anyone trying to shrink our stack that we're about
-	// to park on a channel. The window between when this G's status
-	// changes and when we set gp.activeStackChans is not safe for
-	// stack shrinking.
-	atomic.Store8(&gp.parkingOnChan, 1)
-	gopark(chanparkcommit, unsafe.Pointer(&c.lock), waitReasonChanReceive, traceEvGoBlockRecv, 2)
-
-	// someone woke us up
-	if mysg != gp.waiting {
-		throw("G waiting list is corrupted")
-	}
-	gp.waiting = nil
-	gp.activeStackChans = false
-	if mysg.releasetime > 0 {
-		blockevent(mysg.releasetime-t0, 2)
-	}
-	success := mysg.success
-	gp.param = nil
-	mysg.c = nil
-	releaseSudog(mysg)
-	return true, success
-}
-
-// recv processes a receive operation on a full channel c.
-// There are 2 parts:
-// 1) The value sent by the sender sg is put into the channel
-//    and the sender is woken up to go on its merry way.
-// 2) The value received by the receiver (the current G) is
-//    written to ep.
-// For synchronous channels, both values are the same.
-// For asynchronous channels, the receiver gets its data from
-// the channel buffer and the sender's data is put in the
-// channel buffer.
-// Channel c must be full and locked. recv unlocks c with unlockf.
-// sg must already be dequeued from c.
-// A non-nil ep must point to the heap or the caller's stack.
-func recv(c *hchan, sg *sudog, ep unsafe.Pointer, unlockf func(), skip int) {
-	if c.dataqsiz == 0 {
-		if raceenabled {
-			racesync(c, sg)
-		}
-		if ep != nil {
-			// copy data from sender
-			recvDirect(c.elemtype, sg, ep)
-		}
-	} else {
-		// Queue is full. Take the item at the
-		// head of the queue. Make the sender enqueue
-		// its item at the tail of the queue. Since the
-		// queue is full, those are both the same slot.
-		qp := chanbuf(c, c.recvx)
-		if raceenabled {
-			racenotify(c, c.recvx, nil)
-			racenotify(c, c.recvx, sg)
-		}
-		// copy data from queue to receiver
-		if ep != nil {
-			typedmemmove(c.elemtype, ep, qp)
-		}
-		// copy data from sender to queue
-		typedmemmove(c.elemtype, qp, sg.elem)
-		c.recvx++
-		if c.recvx == c.dataqsiz {
-			c.recvx = 0
-		}
-		c.sendx = c.recvx // c.sendx = (c.sendx+1) % c.dataqsiz
-	}
-	sg.elem = nil
-	gp := sg.g
-	unlockf()
-	gp.param = unsafe.Pointer(sg)
-	sg.success = true
-	if sg.releasetime != 0 {
-		sg.releasetime = cputicks()
-	}
-	goready(gp, skip+1)
-}
-
-func chanparkcommit(gp *g, chanLock unsafe.Pointer) bool {
-	// There are unlocked sudogs that point into gp's stack. Stack
-	// copying must lock the channels of those sudogs.
-	// Set activeStackChans here instead of before we try parking
-	// because we could self-deadlock in stack growth on the
-	// channel lock.
-	gp.activeStackChans = true
-	// Mark that it's safe for stack shrinking to occur now,
-	// because any thread acquiring this G's stack for shrinking
-	// is guaranteed to observe activeStackChans after this store.
-	atomic.Store8(&gp.parkingOnChan, 0)
-	// Make sure we unlock after setting activeStackChans and
-	// unsetting parkingOnChan. The moment we unlock chanLock
-	// we risk gp getting readied by a channel operation and
-	// so gp could continue running before everything before
-	// the unlock is visible (even to gp itself).
-	unlock((*mutex)(chanLock))
-	return true
-}
-
-// compiler implements
-//
-//	select {
-//	case c <- v:
-//		... foo
-//	default:
-//		... bar
-//	}
-//
-// as
-//
-//	if selectnbsend(c, v) {
-//		... foo
-//	} else {
-//		... bar
-//	}
-//
-func selectnbsend(c *hchan, elem unsafe.Pointer) (selected bool) {
-	return chansend(c, elem, false, getcallerpc())
-}
-
-// compiler implements
-//
-//	select {
-//	case v, ok = <-c:
-//		... foo
-//	default:
-//		... bar
-//	}
-//
-// as
-//
-//	if selected, ok = selectnbrecv(&v, c); selected {
-//		... foo
-//	} else {
-//		... bar
-//	}
-//
-func selectnbrecv(elem unsafe.Pointer, c *hchan) (selected, received bool) {
-	return chanrecv(c, elem, false)
-}
-
-//go:linkname reflect_chansend reflect.chansend
-func reflect_chansend(c *hchan, elem unsafe.Pointer, nb bool) (selected bool) {
-	return chansend(c, elem, !nb, getcallerpc())
-}
-
-//go:linkname reflect_chanrecv reflect.chanrecv
-func reflect_chanrecv(c *hchan, nb bool, elem unsafe.Pointer) (selected bool, received bool) {
-	return chanrecv(c, elem, !nb)
-}
-
-//go:linkname reflect_chanlen reflect.chanlen
-func reflect_chanlen(c *hchan) int {
-	if c == nil {
-		return 0
-	}
-	return int(c.qcount)
-}
-
-//go:linkname reflectlite_chanlen internal/reflectlite.chanlen
-func reflectlite_chanlen(c *hchan) int {
-	if c == nil {
-		return 0
-	}
-	return int(c.qcount)
-}
-
-//go:linkname reflect_chancap reflect.chancap
-func reflect_chancap(c *hchan) int {
-	if c == nil {
-		return 0
-	}
-	return int(c.dataqsiz)
-}
-
-//go:linkname reflect_chanclose reflect.chanclose
-func reflect_chanclose(c *hchan) {
-	closechan(c)
-}
-
-func (q *waitq) enqueue(sgp *sudog) {
-	sgp.next = nil
-	x := q.last
-	if x == nil {
-		sgp.prev = nil
-		q.first = sgp
-		q.last = sgp
-		return
-	}
-	sgp.prev = x
-	x.next = sgp
-	q.last = sgp
-}
-
-func (q *waitq) dequeue() *sudog {
-	for {
-		sgp := q.first
-		if sgp == nil {
-			return nil
-		}
-		y := sgp.next
-		if y == nil {
-			q.first = nil
-			q.last = nil
-		} else {
-			y.prev = nil
-			q.first = y
-			sgp.next = nil // mark as removed (see dequeueSudog)
-		}
-
-		// if a goroutine was put on this queue because of a
-		// select, there is a small window between the goroutine
-		// being woken up by a different case and it grabbing the
-		// channel locks. Once it has the lock
-		// it removes itself from the queue, so we won't see it after that.
-		// We use a flag in the G struct to tell us when someone
-		// else has won the race to signal this goroutine but the goroutine
-		// hasn't removed itself from the queue yet.
-		if sgp.isSelect && !atomic.Cas(&sgp.g.selectDone, 0, 1) {
-			continue
-		}
-
-		return sgp
-	}
-}
-
-func (c *hchan) raceaddr() unsafe.Pointer {
-	// Treat read-like and write-like operations on the channel to
-	// happen at this address. Avoid using the address of qcount
-	// or dataqsiz, because the len() and cap() builtins read
-	// those addresses, and we don't want them racing with
-	// operations like close().
-	return unsafe.Pointer(&c.buf)
-}
-
-func racesync(c *hchan, sg *sudog) {
-	racerelease(chanbuf(c, 0))
-	raceacquireg(sg.g, chanbuf(c, 0))
-	racereleaseg(sg.g, chanbuf(c, 0))
-	raceacquire(chanbuf(c, 0))
-}
-
-// Notify the race detector of a send or receive involving buffer entry idx
-// and a channel c or its communicating partner sg.
-// This function handles the special case of c.elemsize==0.
-func racenotify(c *hchan, idx uint, sg *sudog) {
-	// We could have passed the unsafe.Pointer corresponding to entry idx
-	// instead of idx itself.  However, in a future version of this function,
-	// we can use idx to better handle the case of elemsize==0.
-	// A future improvement to the detector is to call TSan with c and idx:
-	// this way, Go will continue to not allocating buffer entries for channels
-	// of elemsize==0, yet the race detector can be made to handle multiple
-	// sync objects underneath the hood (one sync object per idx)
-	qp := chanbuf(c, idx)
-	// When elemsize==0, we don't allocate a full buffer for the channel.
-	// Instead of individual buffer entries, the race detector uses the
-	// c.buf as the only buffer entry.  This simplification prevents us from
-	// following the memory model's happens-before rules (rules that are
-	// implemented in racereleaseacquire).  Instead, we accumulate happens-before
-	// information in the synchronization object associated with c.buf.
-	if c.elemsize == 0 {
-		if sg == nil {
-			raceacquire(qp)
-			racerelease(qp)
-		} else {
-			raceacquireg(sg.g, qp)
-			racereleaseg(sg.g, qp)
-		}
-	} else {
-		if sg == nil {
-			racereleaseacquire(qp)
-		} else {
-			racereleaseacquireg(sg.g, qp)
-		}
-	}
-}
diff --git a/contrib/go/_std_1.18/src/runtime/compiler.go b/contrib/go/_std_1.18/src/runtime/compiler.go
deleted file mode 100644
index 1ebc62dea1..0000000000
--- a/contrib/go/_std_1.18/src/runtime/compiler.go
+++ /dev/null
@@ -1,13 +0,0 @@
-// Copyright 2012 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-// Compiler is the name of the compiler toolchain that built the
-// running binary. Known toolchains are:
-//
-//	gc      Also known as cmd/compile.
-//	gccgo   The gccgo front end, part of the GCC compiler suite.
-//
-const Compiler = "gc"
diff --git a/contrib/go/_std_1.18/src/runtime/cpuprof.go b/contrib/go/_std_1.18/src/runtime/cpuprof.go
deleted file mode 100644
index 48cef46fe9..0000000000
--- a/contrib/go/_std_1.18/src/runtime/cpuprof.go
+++ /dev/null
@@ -1,218 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// CPU profiling.
-//
-// The signal handler for the profiling clock tick adds a new stack trace
-// to a log of recent traces. The log is read by a user goroutine that
-// turns it into formatted profile data. If the reader does not keep up
-// with the log, those writes will be recorded as a count of lost records.
-// The actual profile buffer is in profbuf.go.
-
-package runtime
-
-import (
-	"internal/abi"
-	"runtime/internal/atomic"
-	"runtime/internal/sys"
-	"unsafe"
-)
-
-const maxCPUProfStack = 64
-
-type cpuProfile struct {
-	lock mutex
-	on   bool     // profiling is on
-	log  *profBuf // profile events written here
-
-	// extra holds extra stacks accumulated in addNonGo
-	// corresponding to profiling signals arriving on
-	// non-Go-created threads. Those stacks are written
-	// to log the next time a normal Go thread gets the
-	// signal handler.
-	// Assuming the stacks are 2 words each (we don't get
-	// a full traceback from those threads), plus one word
-	// size for framing, 100 Hz profiling would generate
-	// 300 words per second.
-	// Hopefully a normal Go thread will get the profiling
-	// signal at least once every few seconds.
-	extra      [1000]uintptr
-	numExtra   int
-	lostExtra  uint64 // count of frames lost because extra is full
-	lostAtomic uint64 // count of frames lost because of being in atomic64 on mips/arm; updated racily
-}
-
-var cpuprof cpuProfile
-
-// SetCPUProfileRate sets the CPU profiling rate to hz samples per second.
-// If hz <= 0, SetCPUProfileRate turns off profiling.
-// If the profiler is on, the rate cannot be changed without first turning it off.
-//
-// Most clients should use the runtime/pprof package or
-// the testing package's -test.cpuprofile flag instead of calling
-// SetCPUProfileRate directly.
-func SetCPUProfileRate(hz int) {
-	// Clamp hz to something reasonable.
-	if hz < 0 {
-		hz = 0
-	}
-	if hz > 1000000 {
-		hz = 1000000
-	}
-
-	lock(&cpuprof.lock)
-	if hz > 0 {
-		if cpuprof.on || cpuprof.log != nil {
-			print("runtime: cannot set cpu profile rate until previous profile has finished.\n")
-			unlock(&cpuprof.lock)
-			return
-		}
-
-		cpuprof.on = true
-		cpuprof.log = newProfBuf(1, 1<<17, 1<<14)
-		hdr := [1]uint64{uint64(hz)}
-		cpuprof.log.write(nil, nanotime(), hdr[:], nil)
-		setcpuprofilerate(int32(hz))
-	} else if cpuprof.on {
-		setcpuprofilerate(0)
-		cpuprof.on = false
-		cpuprof.addExtra()
-		cpuprof.log.close()
-	}
-	unlock(&cpuprof.lock)
-}
-
-// add adds the stack trace to the profile.
-// It is called from signal handlers and other limited environments
-// and cannot allocate memory or acquire locks that might be
-// held at the time of the signal, nor can it use substantial amounts
-// of stack.
-//go:nowritebarrierrec
-func (p *cpuProfile) add(tagPtr *unsafe.Pointer, stk []uintptr) {
-	// Simple cas-lock to coordinate with setcpuprofilerate.
-	for !atomic.Cas(&prof.signalLock, 0, 1) {
-		osyield()
-	}
-
-	if prof.hz != 0 { // implies cpuprof.log != nil
-		if p.numExtra > 0 || p.lostExtra > 0 || p.lostAtomic > 0 {
-			p.addExtra()
-		}
-		hdr := [1]uint64{1}
-		// Note: write "knows" that the argument is &gp.labels,
-		// because otherwise its write barrier behavior may not
-		// be correct. See the long comment there before
-		// changing the argument here.
-		cpuprof.log.write(tagPtr, nanotime(), hdr[:], stk)
-	}
-
-	atomic.Store(&prof.signalLock, 0)
-}
-
-// addNonGo adds the non-Go stack trace to the profile.
-// It is called from a non-Go thread, so we cannot use much stack at all,
-// nor do anything that needs a g or an m.
-// In particular, we can't call cpuprof.log.write.
-// Instead, we copy the stack into cpuprof.extra,
-// which will be drained the next time a Go thread
-// gets the signal handling event.
-//go:nosplit
-//go:nowritebarrierrec
-func (p *cpuProfile) addNonGo(stk []uintptr) {
-	// Simple cas-lock to coordinate with SetCPUProfileRate.
-	// (Other calls to add or addNonGo should be blocked out
-	// by the fact that only one SIGPROF can be handled by the
-	// process at a time. If not, this lock will serialize those too.)
-	for !atomic.Cas(&prof.signalLock, 0, 1) {
-		osyield()
-	}
-
-	if cpuprof.numExtra+1+len(stk) < len(cpuprof.extra) {
-		i := cpuprof.numExtra
-		cpuprof.extra[i] = uintptr(1 + len(stk))
-		copy(cpuprof.extra[i+1:], stk)
-		cpuprof.numExtra += 1 + len(stk)
-	} else {
-		cpuprof.lostExtra++
-	}
-
-	atomic.Store(&prof.signalLock, 0)
-}
-
-// addExtra adds the "extra" profiling events,
-// queued by addNonGo, to the profile log.
-// addExtra is called either from a signal handler on a Go thread
-// or from an ordinary goroutine; either way it can use stack
-// and has a g. The world may be stopped, though.
-func (p *cpuProfile) addExtra() {
-	// Copy accumulated non-Go profile events.
-	hdr := [1]uint64{1}
-	for i := 0; i < p.numExtra; {
-		p.log.write(nil, 0, hdr[:], p.extra[i+1:i+int(p.extra[i])])
-		i += int(p.extra[i])
-	}
-	p.numExtra = 0
-
-	// Report any lost events.
-	if p.lostExtra > 0 {
-		hdr := [1]uint64{p.lostExtra}
-		lostStk := [2]uintptr{
-			abi.FuncPCABIInternal(_LostExternalCode) + sys.PCQuantum,
-			abi.FuncPCABIInternal(_ExternalCode) + sys.PCQuantum,
-		}
-		p.log.write(nil, 0, hdr[:], lostStk[:])
-		p.lostExtra = 0
-	}
-
-	if p.lostAtomic > 0 {
-		hdr := [1]uint64{p.lostAtomic}
-		lostStk := [2]uintptr{
-			abi.FuncPCABIInternal(_LostSIGPROFDuringAtomic64) + sys.PCQuantum,
-			abi.FuncPCABIInternal(_System) + sys.PCQuantum,
-		}
-		p.log.write(nil, 0, hdr[:], lostStk[:])
-		p.lostAtomic = 0
-	}
-
-}
-
-// CPUProfile panics.
-// It formerly provided raw access to chunks of
-// a pprof-format profile generated by the runtime.
-// The details of generating that format have changed,
-// so this functionality has been removed.
-//
-// Deprecated: Use the runtime/pprof package,
-// or the handlers in the net/http/pprof package,
-// or the testing package's -test.cpuprofile flag instead.
-func CPUProfile() []byte {
-	panic("CPUProfile no longer available")
-}
-
-//go:linkname runtime_pprof_runtime_cyclesPerSecond runtime/pprof.runtime_cyclesPerSecond
-func runtime_pprof_runtime_cyclesPerSecond() int64 {
-	return tickspersecond()
-}
-
-// readProfile, provided to runtime/pprof, returns the next chunk of
-// binary CPU profiling stack trace data, blocking until data is available.
-// If profiling is turned off and all the profile data accumulated while it was
-// on has been returned, readProfile returns eof=true.
-// The caller must save the returned data and tags before calling readProfile again.
-// The returned data contains a whole number of records, and tags contains
-// exactly one entry per record.
-//
-//go:linkname runtime_pprof_readProfile runtime/pprof.readProfile
-func runtime_pprof_readProfile() ([]uint64, []unsafe.Pointer, bool) {
-	lock(&cpuprof.lock)
-	log := cpuprof.log
-	unlock(&cpuprof.lock)
-	data, tags, eof := log.read(profBufBlocking)
-	if len(data) == 0 && eof {
-		lock(&cpuprof.lock)
-		cpuprof.log = nil
-		unlock(&cpuprof.lock)
-	}
-	return data, tags, eof
-}
diff --git a/contrib/go/_std_1.18/src/runtime/cputicks.go b/contrib/go/_std_1.18/src/runtime/cputicks.go
deleted file mode 100644
index 2cf3240333..0000000000
--- a/contrib/go/_std_1.18/src/runtime/cputicks.go
+++ /dev/null
@@ -1,11 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build !arm && !arm64 && !mips64 && !mips64le && !mips && !mipsle && !wasm
-
-package runtime
-
-// careful: cputicks is not guaranteed to be monotonic! In particular, we have
-// noticed drift between cpus on certain os/arch combinations. See issue 8976.
-func cputicks() int64
diff --git a/contrib/go/_std_1.18/src/runtime/debug.go b/contrib/go/_std_1.18/src/runtime/debug.go
deleted file mode 100644
index 2703a0ce01..0000000000
--- a/contrib/go/_std_1.18/src/runtime/debug.go
+++ /dev/null
@@ -1,116 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"runtime/internal/atomic"
-	"unsafe"
-)
-
-// GOMAXPROCS sets the maximum number of CPUs that can be executing
-// simultaneously and returns the previous setting. It defaults to
-// the value of runtime.NumCPU. If n < 1, it does not change the current setting.
-// This call will go away when the scheduler improves.
-func GOMAXPROCS(n int) int {
-	if GOARCH == "wasm" && n > 1 {
-		n = 1 // WebAssembly has no threads yet, so only one CPU is possible.
-	}
-
-	lock(&sched.lock)
-	ret := int(gomaxprocs)
-	unlock(&sched.lock)
-	if n <= 0 || n == ret {
-		return ret
-	}
-
-	stopTheWorldGC("GOMAXPROCS")
-
-	// newprocs will be processed by startTheWorld
-	newprocs = int32(n)
-
-	startTheWorldGC()
-	return ret
-}
-
-// NumCPU returns the number of logical CPUs usable by the current process.
-//
-// The set of available CPUs is checked by querying the operating system
-// at process startup. Changes to operating system CPU allocation after
-// process startup are not reflected.
-func NumCPU() int {
-	return int(ncpu)
-}
-
-// NumCgoCall returns the number of cgo calls made by the current process.
-func NumCgoCall() int64 {
-	var n = int64(atomic.Load64(&ncgocall))
-	for mp := (*m)(atomic.Loadp(unsafe.Pointer(&allm))); mp != nil; mp = mp.alllink {
-		n += int64(mp.ncgocall)
-	}
-	return n
-}
-
-// NumGoroutine returns the number of goroutines that currently exist.
-func NumGoroutine() int {
-	return int(gcount())
-}
-
-//go:linkname debug_modinfo runtime/debug.modinfo
-func debug_modinfo() string {
-	return modinfo
-}
-
-// mayMoreStackPreempt is a maymorestack hook that forces a preemption
-// at every possible cooperative preemption point.
-//
-// This is valuable to apply to the runtime, which can be sensitive to
-// preemption points. To apply this to all preemption points in the
-// runtime and runtime-like code, use the following in bash or zsh:
-//
-//   X=(-{gc,asm}flags={runtime/...,reflect,sync}=-d=maymorestack=runtime.mayMoreStackPreempt) GOFLAGS=${X[@]}
-//
-// This must be deeply nosplit because it is called from a function
-// prologue before the stack is set up and because the compiler will
-// call it from any splittable prologue (leading to infinite
-// recursion).
-//
-// Ideally it should also use very little stack because the linker
-// doesn't currently account for this in nosplit stack depth checking.
-//
-//go:nosplit
-//
-// Ensure mayMoreStackPreempt can be called for all ABIs.
-//
-//go:linkname mayMoreStackPreempt
-func mayMoreStackPreempt() {
-	// Don't do anything on the g0 or gsignal stack.
-	g := getg()
-	if g == g.m.g0 || g == g.m.gsignal {
-		return
-	}
-	// Force a preemption, unless the stack is already poisoned.
-	if g.stackguard0 < stackPoisonMin {
-		g.stackguard0 = stackPreempt
-	}
-}
-
-// mayMoreStackMove is a maymorestack hook that forces stack movement
-// at every possible point.
-//
-// See mayMoreStackPreempt.
-//
-//go:nosplit
-//go:linkname mayMoreStackMove
-func mayMoreStackMove() {
-	// Don't do anything on the g0 or gsignal stack.
-	g := getg()
-	if g == g.m.g0 || g == g.m.gsignal {
-		return
-	}
-	// Force stack movement, unless the stack is already poisoned.
-	if g.stackguard0 < stackPoisonMin {
-		g.stackguard0 = stackForceMove
-	}
-}
diff --git a/contrib/go/_std_1.18/src/runtime/debuglog.go b/contrib/go/_std_1.18/src/runtime/debuglog.go
deleted file mode 100644
index 75b91c4216..0000000000
--- a/contrib/go/_std_1.18/src/runtime/debuglog.go
+++ /dev/null
@@ -1,820 +0,0 @@
-// Copyright 2019 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file provides an internal debug logging facility. The debug
-// log is a lightweight, in-memory, per-M ring buffer. By default, the
-// runtime prints the debug log on panic.
-//
-// To print something to the debug log, call dlog to obtain a dlogger
-// and use the methods on that to add values. The values will be
-// space-separated in the output (much like println).
-//
-// This facility can be enabled by passing -tags debuglog when
-// building. Without this tag, dlog calls compile to nothing.
-
-package runtime
-
-import (
-	"runtime/internal/atomic"
-	"unsafe"
-)
-
-// debugLogBytes is the size of each per-M ring buffer. This is
-// allocated off-heap to avoid blowing up the M and hence the GC'd
-// heap size.
-const debugLogBytes = 16 << 10
-
-// debugLogStringLimit is the maximum number of bytes in a string.
-// Above this, the string will be truncated with "..(n more bytes).."
-const debugLogStringLimit = debugLogBytes / 8
-
-// dlog returns a debug logger. The caller can use methods on the
-// returned logger to add values, which will be space-separated in the
-// final output, much like println. The caller must call end() to
-// finish the message.
-//
-// dlog can be used from highly-constrained corners of the runtime: it
-// is safe to use in the signal handler, from within the write
-// barrier, from within the stack implementation, and in places that
-// must be recursively nosplit.
-//
-// This will be compiled away if built without the debuglog build tag.
-// However, argument construction may not be. If any of the arguments
-// are not literals or trivial expressions, consider protecting the
-// call with "if dlogEnabled".
-//
-//go:nosplit
-//go:nowritebarrierrec
-func dlog() *dlogger {
-	if !dlogEnabled {
-		return nil
-	}
-
-	// Get the time.
-	tick, nano := uint64(cputicks()), uint64(nanotime())
-
-	// Try to get a cached logger.
-	l := getCachedDlogger()
-
-	// If we couldn't get a cached logger, try to get one from the
-	// global pool.
-	if l == nil {
-		allp := (*uintptr)(unsafe.Pointer(&allDloggers))
-		all := (*dlogger)(unsafe.Pointer(atomic.Loaduintptr(allp)))
-		for l1 := all; l1 != nil; l1 = l1.allLink {
-			if atomic.Load(&l1.owned) == 0 && atomic.Cas(&l1.owned, 0, 1) {
-				l = l1
-				break
-			}
-		}
-	}
-
-	// If that failed, allocate a new logger.
-	if l == nil {
-		l = (*dlogger)(sysAlloc(unsafe.Sizeof(dlogger{}), nil))
-		if l == nil {
-			throw("failed to allocate debug log")
-		}
-		l.w.r.data = &l.w.data
-		l.owned = 1
-
-		// Prepend to allDloggers list.
-		headp := (*uintptr)(unsafe.Pointer(&allDloggers))
-		for {
-			head := atomic.Loaduintptr(headp)
-			l.allLink = (*dlogger)(unsafe.Pointer(head))
-			if atomic.Casuintptr(headp, head, uintptr(unsafe.Pointer(l))) {
-				break
-			}
-		}
-	}
-
-	// If the time delta is getting too high, write a new sync
-	// packet. We set the limit so we don't write more than 6
-	// bytes of delta in the record header.
-	const deltaLimit = 1<<(3*7) - 1 // ~2ms between sync packets
-	if tick-l.w.tick > deltaLimit || nano-l.w.nano > deltaLimit {
-		l.w.writeSync(tick, nano)
-	}
-
-	// Reserve space for framing header.
-	l.w.ensure(debugLogHeaderSize)
-	l.w.write += debugLogHeaderSize
-
-	// Write record header.
-	l.w.uvarint(tick - l.w.tick)
-	l.w.uvarint(nano - l.w.nano)
-	gp := getg()
-	if gp != nil && gp.m != nil && gp.m.p != 0 {
-		l.w.varint(int64(gp.m.p.ptr().id))
-	} else {
-		l.w.varint(-1)
-	}
-
-	return l
-}
-
-// A dlogger writes to the debug log.
-//
-// To obtain a dlogger, call dlog(). When done with the dlogger, call
-// end().
-//
-//go:notinheap
-type dlogger struct {
-	w debugLogWriter
-
-	// allLink is the next dlogger in the allDloggers list.
-	allLink *dlogger
-
-	// owned indicates that this dlogger is owned by an M. This is
-	// accessed atomically.
-	owned uint32
-}
-
-// allDloggers is a list of all dloggers, linked through
-// dlogger.allLink. This is accessed atomically. This is prepend only,
-// so it doesn't need to protect against ABA races.
-var allDloggers *dlogger
-
-//go:nosplit
-func (l *dlogger) end() {
-	if !dlogEnabled {
-		return
-	}
-
-	// Fill in framing header.
-	size := l.w.write - l.w.r.end
-	if !l.w.writeFrameAt(l.w.r.end, size) {
-		throw("record too large")
-	}
-
-	// Commit the record.
-	l.w.r.end = l.w.write
-
-	// Attempt to return this logger to the cache.
-	if putCachedDlogger(l) {
-		return
-	}
-
-	// Return the logger to the global pool.
-	atomic.Store(&l.owned, 0)
-}
-
-const (
-	debugLogUnknown = 1 + iota
-	debugLogBoolTrue
-	debugLogBoolFalse
-	debugLogInt
-	debugLogUint
-	debugLogHex
-	debugLogPtr
-	debugLogString
-	debugLogConstString
-	debugLogStringOverflow
-
-	debugLogPC
-	debugLogTraceback
-)
-
-//go:nosplit
-func (l *dlogger) b(x bool) *dlogger {
-	if !dlogEnabled {
-		return l
-	}
-	if x {
-		l.w.byte(debugLogBoolTrue)
-	} else {
-		l.w.byte(debugLogBoolFalse)
-	}
-	return l
-}
-
-//go:nosplit
-func (l *dlogger) i(x int) *dlogger {
-	return l.i64(int64(x))
-}
-
-//go:nosplit
-func (l *dlogger) i8(x int8) *dlogger {
-	return l.i64(int64(x))
-}
-
-//go:nosplit
-func (l *dlogger) i16(x int16) *dlogger {
-	return l.i64(int64(x))
-}
-
-//go:nosplit
-func (l *dlogger) i32(x int32) *dlogger {
-	return l.i64(int64(x))
-}
-
-//go:nosplit
-func (l *dlogger) i64(x int64) *dlogger {
-	if !dlogEnabled {
-		return l
-	}
-	l.w.byte(debugLogInt)
-	l.w.varint(x)
-	return l
-}
-
-//go:nosplit
-func (l *dlogger) u(x uint) *dlogger {
-	return l.u64(uint64(x))
-}
-
-//go:nosplit
-func (l *dlogger) uptr(x uintptr) *dlogger {
-	return l.u64(uint64(x))
-}
-
-//go:nosplit
-func (l *dlogger) u8(x uint8) *dlogger {
-	return l.u64(uint64(x))
-}
-
-//go:nosplit
-func (l *dlogger) u16(x uint16) *dlogger {
-	return l.u64(uint64(x))
-}
-
-//go:nosplit
-func (l *dlogger) u32(x uint32) *dlogger {
-	return l.u64(uint64(x))
-}
-
-//go:nosplit
-func (l *dlogger) u64(x uint64) *dlogger {
-	if !dlogEnabled {
-		return l
-	}
-	l.w.byte(debugLogUint)
-	l.w.uvarint(x)
-	return l
-}
-
-//go:nosplit
-func (l *dlogger) hex(x uint64) *dlogger {
-	if !dlogEnabled {
-		return l
-	}
-	l.w.byte(debugLogHex)
-	l.w.uvarint(x)
-	return l
-}
-
-//go:nosplit
-func (l *dlogger) p(x any) *dlogger {
-	if !dlogEnabled {
-		return l
-	}
-	l.w.byte(debugLogPtr)
-	if x == nil {
-		l.w.uvarint(0)
-	} else {
-		v := efaceOf(&x)
-		switch v._type.kind & kindMask {
-		case kindChan, kindFunc, kindMap, kindPtr, kindUnsafePointer:
-			l.w.uvarint(uint64(uintptr(v.data)))
-		default:
-			throw("not a pointer type")
-		}
-	}
-	return l
-}
-
-//go:nosplit
-func (l *dlogger) s(x string) *dlogger {
-	if !dlogEnabled {
-		return l
-	}
-	str := stringStructOf(&x)
-	datap := &firstmoduledata
-	if len(x) > 4 && datap.etext <= uintptr(str.str) && uintptr(str.str) < datap.end {
-		// String constants are in the rodata section, which
-		// isn't recorded in moduledata. But it has to be
-		// somewhere between etext and end.
-		l.w.byte(debugLogConstString)
-		l.w.uvarint(uint64(str.len))
-		l.w.uvarint(uint64(uintptr(str.str) - datap.etext))
-	} else {
-		l.w.byte(debugLogString)
-		var b []byte
-		bb := (*slice)(unsafe.Pointer(&b))
-		bb.array = str.str
-		bb.len, bb.cap = str.len, str.len
-		if len(b) > debugLogStringLimit {
-			b = b[:debugLogStringLimit]
-		}
-		l.w.uvarint(uint64(len(b)))
-		l.w.bytes(b)
-		if len(b) != len(x) {
-			l.w.byte(debugLogStringOverflow)
-			l.w.uvarint(uint64(len(x) - len(b)))
-		}
-	}
-	return l
-}
-
-//go:nosplit
-func (l *dlogger) pc(x uintptr) *dlogger {
-	if !dlogEnabled {
-		return l
-	}
-	l.w.byte(debugLogPC)
-	l.w.uvarint(uint64(x))
-	return l
-}
-
-//go:nosplit
-func (l *dlogger) traceback(x []uintptr) *dlogger {
-	if !dlogEnabled {
-		return l
-	}
-	l.w.byte(debugLogTraceback)
-	l.w.uvarint(uint64(len(x)))
-	for _, pc := range x {
-		l.w.uvarint(uint64(pc))
-	}
-	return l
-}
-
-// A debugLogWriter is a ring buffer of binary debug log records.
-//
-// A log record consists of a 2-byte framing header and a sequence of
-// fields. The framing header gives the size of the record as a little
-// endian 16-bit value. Each field starts with a byte indicating its
-// type, followed by type-specific data. If the size in the framing
-// header is 0, it's a sync record consisting of two little endian
-// 64-bit values giving a new time base.
-//
-// Because this is a ring buffer, new records will eventually
-// overwrite old records. Hence, it maintains a reader that consumes
-// the log as it gets overwritten. That reader state is where an
-// actual log reader would start.
-//
-//go:notinheap
-type debugLogWriter struct {
-	write uint64
-	data  debugLogBuf
-
-	// tick and nano are the time bases from the most recently
-	// written sync record.
-	tick, nano uint64
-
-	// r is a reader that consumes records as they get overwritten
-	// by the writer. It also acts as the initial reader state
-	// when printing the log.
-	r debugLogReader
-
-	// buf is a scratch buffer for encoding. This is here to
-	// reduce stack usage.
-	buf [10]byte
-}
-
-//go:notinheap
-type debugLogBuf [debugLogBytes]byte
-
-const (
-	// debugLogHeaderSize is the number of bytes in the framing
-	// header of every dlog record.
-	debugLogHeaderSize = 2
-
-	// debugLogSyncSize is the number of bytes in a sync record.
-	debugLogSyncSize = debugLogHeaderSize + 2*8
-)
-
-//go:nosplit
-func (l *debugLogWriter) ensure(n uint64) {
-	for l.write+n >= l.r.begin+uint64(len(l.data)) {
-		// Consume record at begin.
-		if l.r.skip() == ^uint64(0) {
-			// Wrapped around within a record.
-			//
-			// TODO(austin): It would be better to just
-			// eat the whole buffer at this point, but we
-			// have to communicate that to the reader
-			// somehow.
-			throw("record wrapped around")
-		}
-	}
-}
-
-//go:nosplit
-func (l *debugLogWriter) writeFrameAt(pos, size uint64) bool {
-	l.data[pos%uint64(len(l.data))] = uint8(size)
-	l.data[(pos+1)%uint64(len(l.data))] = uint8(size >> 8)
-	return size <= 0xFFFF
-}
-
-//go:nosplit
-func (l *debugLogWriter) writeSync(tick, nano uint64) {
-	l.tick, l.nano = tick, nano
-	l.ensure(debugLogHeaderSize)
-	l.writeFrameAt(l.write, 0)
-	l.write += debugLogHeaderSize
-	l.writeUint64LE(tick)
-	l.writeUint64LE(nano)
-	l.r.end = l.write
-}
-
-//go:nosplit
-func (l *debugLogWriter) writeUint64LE(x uint64) {
-	var b [8]byte
-	b[0] = byte(x)
-	b[1] = byte(x >> 8)
-	b[2] = byte(x >> 16)
-	b[3] = byte(x >> 24)
-	b[4] = byte(x >> 32)
-	b[5] = byte(x >> 40)
-	b[6] = byte(x >> 48)
-	b[7] = byte(x >> 56)
-	l.bytes(b[:])
-}
-
-//go:nosplit
-func (l *debugLogWriter) byte(x byte) {
-	l.ensure(1)
-	pos := l.write
-	l.write++
-	l.data[pos%uint64(len(l.data))] = x
-}
-
-//go:nosplit
-func (l *debugLogWriter) bytes(x []byte) {
-	l.ensure(uint64(len(x)))
-	pos := l.write
-	l.write += uint64(len(x))
-	for len(x) > 0 {
-		n := copy(l.data[pos%uint64(len(l.data)):], x)
-		pos += uint64(n)
-		x = x[n:]
-	}
-}
-
-//go:nosplit
-func (l *debugLogWriter) varint(x int64) {
-	var u uint64
-	if x < 0 {
-		u = (^uint64(x) << 1) | 1 // complement i, bit 0 is 1
-	} else {
-		u = (uint64(x) << 1) // do not complement i, bit 0 is 0
-	}
-	l.uvarint(u)
-}
-
-//go:nosplit
-func (l *debugLogWriter) uvarint(u uint64) {
-	i := 0
-	for u >= 0x80 {
-		l.buf[i] = byte(u) | 0x80
-		u >>= 7
-		i++
-	}
-	l.buf[i] = byte(u)
-	i++
-	l.bytes(l.buf[:i])
-}
-
-type debugLogReader struct {
-	data *debugLogBuf
-
-	// begin and end are the positions in the log of the beginning
-	// and end of the log data, modulo len(data).
-	begin, end uint64
-
-	// tick and nano are the current time base at begin.
-	tick, nano uint64
-}
-
-//go:nosplit
-func (r *debugLogReader) skip() uint64 {
-	// Read size at pos.
-	if r.begin+debugLogHeaderSize > r.end {
-		return ^uint64(0)
-	}
-	size := uint64(r.readUint16LEAt(r.begin))
-	if size == 0 {
-		// Sync packet.
-		r.tick = r.readUint64LEAt(r.begin + debugLogHeaderSize)
-		r.nano = r.readUint64LEAt(r.begin + debugLogHeaderSize + 8)
-		size = debugLogSyncSize
-	}
-	if r.begin+size > r.end {
-		return ^uint64(0)
-	}
-	r.begin += size
-	return size
-}
-
-//go:nosplit
-func (r *debugLogReader) readUint16LEAt(pos uint64) uint16 {
-	return uint16(r.data[pos%uint64(len(r.data))]) |
-		uint16(r.data[(pos+1)%uint64(len(r.data))])<<8
-}
-
-//go:nosplit
-func (r *debugLogReader) readUint64LEAt(pos uint64) uint64 {
-	var b [8]byte
-	for i := range b {
-		b[i] = r.data[pos%uint64(len(r.data))]
-		pos++
-	}
-	return uint64(b[0]) | uint64(b[1])<<8 |
-		uint64(b[2])<<16 | uint64(b[3])<<24 |
-		uint64(b[4])<<32 | uint64(b[5])<<40 |
-		uint64(b[6])<<48 | uint64(b[7])<<56
-}
-
-func (r *debugLogReader) peek() (tick uint64) {
-	// Consume any sync records.
-	size := uint64(0)
-	for size == 0 {
-		if r.begin+debugLogHeaderSize > r.end {
-			return ^uint64(0)
-		}
-		size = uint64(r.readUint16LEAt(r.begin))
-		if size != 0 {
-			break
-		}
-		if r.begin+debugLogSyncSize > r.end {
-			return ^uint64(0)
-		}
-		// Sync packet.
-		r.tick = r.readUint64LEAt(r.begin + debugLogHeaderSize)
-		r.nano = r.readUint64LEAt(r.begin + debugLogHeaderSize + 8)
-		r.begin += debugLogSyncSize
-	}
-
-	// Peek tick delta.
-	if r.begin+size > r.end {
-		return ^uint64(0)
-	}
-	pos := r.begin + debugLogHeaderSize
-	var u uint64
-	for i := uint(0); ; i += 7 {
-		b := r.data[pos%uint64(len(r.data))]
-		pos++
-		u |= uint64(b&^0x80) << i
-		if b&0x80 == 0 {
-			break
-		}
-	}
-	if pos > r.begin+size {
-		return ^uint64(0)
-	}
-	return r.tick + u
-}
-
-func (r *debugLogReader) header() (end, tick, nano uint64, p int) {
-	// Read size. We've already skipped sync packets and checked
-	// bounds in peek.
-	size := uint64(r.readUint16LEAt(r.begin))
-	end = r.begin + size
-	r.begin += debugLogHeaderSize
-
-	// Read tick, nano, and p.
-	tick = r.uvarint() + r.tick
-	nano = r.uvarint() + r.nano
-	p = int(r.varint())
-
-	return
-}
-
-func (r *debugLogReader) uvarint() uint64 {
-	var u uint64
-	for i := uint(0); ; i += 7 {
-		b := r.data[r.begin%uint64(len(r.data))]
-		r.begin++
-		u |= uint64(b&^0x80) << i
-		if b&0x80 == 0 {
-			break
-		}
-	}
-	return u
-}
-
-func (r *debugLogReader) varint() int64 {
-	u := r.uvarint()
-	var v int64
-	if u&1 == 0 {
-		v = int64(u >> 1)
-	} else {
-		v = ^int64(u >> 1)
-	}
-	return v
-}
-
-func (r *debugLogReader) printVal() bool {
-	typ := r.data[r.begin%uint64(len(r.data))]
-	r.begin++
-
-	switch typ {
-	default:
-		print("<unknown field type ", hex(typ), " pos ", r.begin-1, " end ", r.end, ">\n")
-		return false
-
-	case debugLogUnknown:
-		print("<unknown kind>")
-
-	case debugLogBoolTrue:
-		print(true)
-
-	case debugLogBoolFalse:
-		print(false)
-
-	case debugLogInt:
-		print(r.varint())
-
-	case debugLogUint:
-		print(r.uvarint())
-
-	case debugLogHex, debugLogPtr:
-		print(hex(r.uvarint()))
-
-	case debugLogString:
-		sl := r.uvarint()
-		if r.begin+sl > r.end {
-			r.begin = r.end
-			print("<string length corrupted>")
-			break
-		}
-		for sl > 0 {
-			b := r.data[r.begin%uint64(len(r.data)):]
-			if uint64(len(b)) > sl {
-				b = b[:sl]
-			}
-			r.begin += uint64(len(b))
-			sl -= uint64(len(b))
-			gwrite(b)
-		}
-
-	case debugLogConstString:
-		len, ptr := int(r.uvarint()), uintptr(r.uvarint())
-		ptr += firstmoduledata.etext
-		str := stringStruct{
-			str: unsafe.Pointer(ptr),
-			len: len,
-		}
-		s := *(*string)(unsafe.Pointer(&str))
-		print(s)
-
-	case debugLogStringOverflow:
-		print("..(", r.uvarint(), " more bytes)..")
-
-	case debugLogPC:
-		printDebugLogPC(uintptr(r.uvarint()), false)
-
-	case debugLogTraceback:
-		n := int(r.uvarint())
-		for i := 0; i < n; i++ {
-			print("\n\t")
-			// gentraceback PCs are always return PCs.
-			// Convert them to call PCs.
-			//
-			// TODO(austin): Expand inlined frames.
-			printDebugLogPC(uintptr(r.uvarint()), true)
-		}
-	}
-
-	return true
-}
-
-// printDebugLog prints the debug log.
-func printDebugLog() {
-	if !dlogEnabled {
-		return
-	}
-
-	// This function should not panic or throw since it is used in
-	// the fatal panic path and this may deadlock.
-
-	printlock()
-
-	// Get the list of all debug logs.
-	allp := (*uintptr)(unsafe.Pointer(&allDloggers))
-	all := (*dlogger)(unsafe.Pointer(atomic.Loaduintptr(allp)))
-
-	// Count the logs.
-	n := 0
-	for l := all; l != nil; l = l.allLink {
-		n++
-	}
-	if n == 0 {
-		printunlock()
-		return
-	}
-
-	// Prepare read state for all logs.
-	type readState struct {
-		debugLogReader
-		first    bool
-		lost     uint64
-		nextTick uint64
-	}
-	state1 := sysAlloc(unsafe.Sizeof(readState{})*uintptr(n), nil)
-	if state1 == nil {
-		println("failed to allocate read state for", n, "logs")
-		printunlock()
-		return
-	}
-	state := (*[1 << 20]readState)(state1)[:n]
-	{
-		l := all
-		for i := range state {
-			s := &state[i]
-			s.debugLogReader = l.w.r
-			s.first = true
-			s.lost = l.w.r.begin
-			s.nextTick = s.peek()
-			l = l.allLink
-		}
-	}
-
-	// Print records.
-	for {
-		// Find the next record.
-		var best struct {
-			tick uint64
-			i    int
-		}
-		best.tick = ^uint64(0)
-		for i := range state {
-			if state[i].nextTick < best.tick {
-				best.tick = state[i].nextTick
-				best.i = i
-			}
-		}
-		if best.tick == ^uint64(0) {
-			break
-		}
-
-		// Print record.
-		s := &state[best.i]
-		if s.first {
-			print(">> begin log ", best.i)
-			if s.lost != 0 {
-				print("; lost first ", s.lost>>10, "KB")
-			}
-			print(" <<\n")
-			s.first = false
-		}
-
-		end, _, nano, p := s.header()
-		oldEnd := s.end
-		s.end = end
-
-		print("[")
-		var tmpbuf [21]byte
-		pnano := int64(nano) - runtimeInitTime
-		if pnano < 0 {
-			// Logged before runtimeInitTime was set.
-			pnano = 0
-		}
-		print(string(itoaDiv(tmpbuf[:], uint64(pnano), 9)))
-		print(" P ", p, "] ")
-
-		for i := 0; s.begin < s.end; i++ {
-			if i > 0 {
-				print(" ")
-			}
-			if !s.printVal() {
-				// Abort this P log.
-				print("<aborting P log>")
-				end = oldEnd
-				break
-			}
-		}
-		println()
-
-		// Move on to the next record.
-		s.begin = end
-		s.end = oldEnd
-		s.nextTick = s.peek()
-	}
-
-	printunlock()
-}
-
-// printDebugLogPC prints a single symbolized PC. If returnPC is true,
-// pc is a return PC that must first be converted to a call PC.
-func printDebugLogPC(pc uintptr, returnPC bool) {
-	fn := findfunc(pc)
-	if returnPC && (!fn.valid() || pc > fn.entry()) {
-		// TODO(austin): Don't back up if the previous frame
-		// was a sigpanic.
-		pc--
-	}
-
-	print(hex(pc))
-	if !fn.valid() {
-		print(" [unknown PC]")
-	} else {
-		name := funcname(fn)
-		file, line := funcline(fn, pc)
-		print(" [", name, "+", hex(pc-fn.entry()),
-			" ", file, ":", line, "]")
-	}
-}
diff --git a/contrib/go/_std_1.18/src/runtime/defs_linux_amd64.go b/contrib/go/_std_1.18/src/runtime/defs_linux_amd64.go
deleted file mode 100644
index 47fb468621..0000000000
--- a/contrib/go/_std_1.18/src/runtime/defs_linux_amd64.go
+++ /dev/null
@@ -1,302 +0,0 @@
-// created by cgo -cdefs and then converted to Go
-// cgo -cdefs defs_linux.go defs1_linux.go
-
-package runtime
-
-import "unsafe"
-
-const (
-	_EINTR  = 0x4
-	_EAGAIN = 0xb
-	_ENOMEM = 0xc
-	_ENOSYS = 0x26
-
-	_PROT_NONE  = 0x0
-	_PROT_READ  = 0x1
-	_PROT_WRITE = 0x2
-	_PROT_EXEC  = 0x4
-
-	_MAP_ANON    = 0x20
-	_MAP_PRIVATE = 0x2
-	_MAP_FIXED   = 0x10
-
-	_MADV_DONTNEED   = 0x4
-	_MADV_FREE       = 0x8
-	_MADV_HUGEPAGE   = 0xe
-	_MADV_NOHUGEPAGE = 0xf
-
-	_SA_RESTART  = 0x10000000
-	_SA_ONSTACK  = 0x8000000
-	_SA_RESTORER = 0x4000000
-	_SA_SIGINFO  = 0x4
-
-	_SI_KERNEL = 0x80
-	_SI_TIMER  = -0x2
-
-	_SIGHUP    = 0x1
-	_SIGINT    = 0x2
-	_SIGQUIT   = 0x3
-	_SIGILL    = 0x4
-	_SIGTRAP   = 0x5
-	_SIGABRT   = 0x6
-	_SIGBUS    = 0x7
-	_SIGFPE    = 0x8
-	_SIGKILL   = 0x9
-	_SIGUSR1   = 0xa
-	_SIGSEGV   = 0xb
-	_SIGUSR2   = 0xc
-	_SIGPIPE   = 0xd
-	_SIGALRM   = 0xe
-	_SIGSTKFLT = 0x10
-	_SIGCHLD   = 0x11
-	_SIGCONT   = 0x12
-	_SIGSTOP   = 0x13
-	_SIGTSTP   = 0x14
-	_SIGTTIN   = 0x15
-	_SIGTTOU   = 0x16
-	_SIGURG    = 0x17
-	_SIGXCPU   = 0x18
-	_SIGXFSZ   = 0x19
-	_SIGVTALRM = 0x1a
-	_SIGPROF   = 0x1b
-	_SIGWINCH  = 0x1c
-	_SIGIO     = 0x1d
-	_SIGPWR    = 0x1e
-	_SIGSYS    = 0x1f
-
-	_SIGRTMIN = 0x20
-
-	_FPE_INTDIV = 0x1
-	_FPE_INTOVF = 0x2
-	_FPE_FLTDIV = 0x3
-	_FPE_FLTOVF = 0x4
-	_FPE_FLTUND = 0x5
-	_FPE_FLTRES = 0x6
-	_FPE_FLTINV = 0x7
-	_FPE_FLTSUB = 0x8
-
-	_BUS_ADRALN = 0x1
-	_BUS_ADRERR = 0x2
-	_BUS_OBJERR = 0x3
-
-	_SEGV_MAPERR = 0x1
-	_SEGV_ACCERR = 0x2
-
-	_ITIMER_REAL    = 0x0
-	_ITIMER_VIRTUAL = 0x1
-	_ITIMER_PROF    = 0x2
-
-	_CLOCK_THREAD_CPUTIME_ID = 0x3
-
-	_SIGEV_THREAD_ID = 0x4
-
-	_EPOLLIN       = 0x1
-	_EPOLLOUT      = 0x4
-	_EPOLLERR      = 0x8
-	_EPOLLHUP      = 0x10
-	_EPOLLRDHUP    = 0x2000
-	_EPOLLET       = 0x80000000
-	_EPOLL_CLOEXEC = 0x80000
-	_EPOLL_CTL_ADD = 0x1
-	_EPOLL_CTL_DEL = 0x2
-	_EPOLL_CTL_MOD = 0x3
-
-	_AF_UNIX    = 0x1
-	_SOCK_DGRAM = 0x2
-)
-
-type timespec struct {
-	tv_sec  int64
-	tv_nsec int64
-}
-
-//go:nosplit
-func (ts *timespec) setNsec(ns int64) {
-	ts.tv_sec = ns / 1e9
-	ts.tv_nsec = ns % 1e9
-}
-
-type timeval struct {
-	tv_sec  int64
-	tv_usec int64
-}
-
-func (tv *timeval) set_usec(x int32) {
-	tv.tv_usec = int64(x)
-}
-
-type sigactiont struct {
-	sa_handler  uintptr
-	sa_flags    uint64
-	sa_restorer uintptr
-	sa_mask     uint64
-}
-
-type siginfoFields struct {
-	si_signo int32
-	si_errno int32
-	si_code  int32
-	// below here is a union; si_addr is the only field we use
-	si_addr uint64
-}
-
-type siginfo struct {
-	siginfoFields
-
-	// Pad struct to the max size in the kernel.
-	_ [_si_max_size - unsafe.Sizeof(siginfoFields{})]byte
-}
-
-type itimerspec struct {
-	it_interval timespec
-	it_value    timespec
-}
-
-type itimerval struct {
-	it_interval timeval
-	it_value    timeval
-}
-
-type sigeventFields struct {
-	value  uintptr
-	signo  int32
-	notify int32
-	// below here is a union; sigev_notify_thread_id is the only field we use
-	sigev_notify_thread_id int32
-}
-
-type sigevent struct {
-	sigeventFields
-
-	// Pad struct to the max size in the kernel.
-	_ [_sigev_max_size - unsafe.Sizeof(sigeventFields{})]byte
-}
-
-type epollevent struct {
-	events uint32
-	data   [8]byte // unaligned uintptr
-}
-
-// created by cgo -cdefs and then converted to Go
-// cgo -cdefs defs_linux.go defs1_linux.go
-
-const (
-	_O_RDONLY   = 0x0
-	_O_NONBLOCK = 0x800
-	_O_CLOEXEC  = 0x80000
-)
-
-type usigset struct {
-	__val [16]uint64
-}
-
-type fpxreg struct {
-	significand [4]uint16
-	exponent    uint16
-	padding     [3]uint16
-}
-
-type xmmreg struct {
-	element [4]uint32
-}
-
-type fpstate struct {
-	cwd       uint16
-	swd       uint16
-	ftw       uint16
-	fop       uint16
-	rip       uint64
-	rdp       uint64
-	mxcsr     uint32
-	mxcr_mask uint32
-	_st       [8]fpxreg
-	_xmm      [16]xmmreg
-	padding   [24]uint32
-}
-
-type fpxreg1 struct {
-	significand [4]uint16
-	exponent    uint16
-	padding     [3]uint16
-}
-
-type xmmreg1 struct {
-	element [4]uint32
-}
-
-type fpstate1 struct {
-	cwd       uint16
-	swd       uint16
-	ftw       uint16
-	fop       uint16
-	rip       uint64
-	rdp       uint64
-	mxcsr     uint32
-	mxcr_mask uint32
-	_st       [8]fpxreg1
-	_xmm      [16]xmmreg1
-	padding   [24]uint32
-}
-
-type fpreg1 struct {
-	significand [4]uint16
-	exponent    uint16
-}
-
-type stackt struct {
-	ss_sp     *byte
-	ss_flags  int32
-	pad_cgo_0 [4]byte
-	ss_size   uintptr
-}
-
-type mcontext struct {
-	gregs       [23]uint64
-	fpregs      *fpstate
-	__reserved1 [8]uint64
-}
-
-type ucontext struct {
-	uc_flags     uint64
-	uc_link      *ucontext
-	uc_stack     stackt
-	uc_mcontext  mcontext
-	uc_sigmask   usigset
-	__fpregs_mem fpstate
-}
-
-type sigcontext struct {
-	r8          uint64
-	r9          uint64
-	r10         uint64
-	r11         uint64
-	r12         uint64
-	r13         uint64
-	r14         uint64
-	r15         uint64
-	rdi         uint64
-	rsi         uint64
-	rbp         uint64
-	rbx         uint64
-	rdx         uint64
-	rax         uint64
-	rcx         uint64
-	rsp         uint64
-	rip         uint64
-	eflags      uint64
-	cs          uint16
-	gs          uint16
-	fs          uint16
-	__pad0      uint16
-	err         uint64
-	trapno      uint64
-	oldmask     uint64
-	cr2         uint64
-	fpstate     *fpstate1
-	__reserved1 [8]uint64
-}
-
-type sockaddr_un struct {
-	family uint16
-	path   [108]byte
-}
diff --git a/contrib/go/_std_1.18/src/runtime/env_posix.go b/contrib/go/_std_1.18/src/runtime/env_posix.go
deleted file mode 100644
index 44086c1d63..0000000000
--- a/contrib/go/_std_1.18/src/runtime/env_posix.go
+++ /dev/null
@@ -1,76 +0,0 @@
-// Copyright 2012 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris || windows || plan9
-
-package runtime
-
-import "unsafe"
-
-func gogetenv(key string) string {
-	env := environ()
-	if env == nil {
-		throw("getenv before env init")
-	}
-	for _, s := range env {
-		if len(s) > len(key) && s[len(key)] == '=' && envKeyEqual(s[:len(key)], key) {
-			return s[len(key)+1:]
-		}
-	}
-	return ""
-}
-
-// envKeyEqual reports whether a == b, with ASCII-only case insensitivity
-// on Windows. The two strings must have the same length.
-func envKeyEqual(a, b string) bool {
-	if GOOS == "windows" { // case insensitive
-		for i := 0; i < len(a); i++ {
-			ca, cb := a[i], b[i]
-			if ca == cb || lowerASCII(ca) == lowerASCII(cb) {
-				continue
-			}
-			return false
-		}
-		return true
-	}
-	return a == b
-}
-
-func lowerASCII(c byte) byte {
-	if 'A' <= c && c <= 'Z' {
-		return c + ('a' - 'A')
-	}
-	return c
-}
-
-var _cgo_setenv unsafe.Pointer   // pointer to C function
-var _cgo_unsetenv unsafe.Pointer // pointer to C function
-
-// Update the C environment if cgo is loaded.
-// Called from syscall.Setenv.
-//go:linkname syscall_setenv_c syscall.setenv_c
-func syscall_setenv_c(k string, v string) {
-	if _cgo_setenv == nil {
-		return
-	}
-	arg := [2]unsafe.Pointer{cstring(k), cstring(v)}
-	asmcgocall(_cgo_setenv, unsafe.Pointer(&arg))
-}
-
-// Update the C environment if cgo is loaded.
-// Called from syscall.unsetenv.
-//go:linkname syscall_unsetenv_c syscall.unsetenv_c
-func syscall_unsetenv_c(k string) {
-	if _cgo_unsetenv == nil {
-		return
-	}
-	arg := [1]unsafe.Pointer{cstring(k)}
-	asmcgocall(_cgo_unsetenv, unsafe.Pointer(&arg))
-}
-
-func cstring(s string) unsafe.Pointer {
-	p := make([]byte, len(s)+1)
-	copy(p, s)
-	return unsafe.Pointer(&p[0])
-}
diff --git a/contrib/go/_std_1.18/src/runtime/error.go b/contrib/go/_std_1.18/src/runtime/error.go
deleted file mode 100644
index 43114f092e..0000000000
--- a/contrib/go/_std_1.18/src/runtime/error.go
+++ /dev/null
@@ -1,329 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import "internal/bytealg"
-
-// The Error interface identifies a run time error.
-type Error interface {
-	error
-
-	// RuntimeError is a no-op function but
-	// serves to distinguish types that are run time
-	// errors from ordinary errors: a type is a
-	// run time error if it has a RuntimeError method.
-	RuntimeError()
-}
-
-// A TypeAssertionError explains a failed type assertion.
-type TypeAssertionError struct {
-	_interface    *_type
-	concrete      *_type
-	asserted      *_type
-	missingMethod string // one method needed by Interface, missing from Concrete
-}
-
-func (*TypeAssertionError) RuntimeError() {}
-
-func (e *TypeAssertionError) Error() string {
-	inter := "interface"
-	if e._interface != nil {
-		inter = e._interface.string()
-	}
-	as := e.asserted.string()
-	if e.concrete == nil {
-		return "interface conversion: " + inter + " is nil, not " + as
-	}
-	cs := e.concrete.string()
-	if e.missingMethod == "" {
-		msg := "interface conversion: " + inter + " is " + cs + ", not " + as
-		if cs == as {
-			// provide slightly clearer error message
-			if e.concrete.pkgpath() != e.asserted.pkgpath() {
-				msg += " (types from different packages)"
-			} else {
-				msg += " (types from different scopes)"
-			}
-		}
-		return msg
-	}
-	return "interface conversion: " + cs + " is not " + as +
-		": missing method " + e.missingMethod
-}
-
-//go:nosplit
-// itoa converts val to a decimal representation. The result is
-// written somewhere within buf and the location of the result is returned.
-// buf must be at least 20 bytes.
-func itoa(buf []byte, val uint64) []byte {
-	i := len(buf) - 1
-	for val >= 10 {
-		buf[i] = byte(val%10 + '0')
-		i--
-		val /= 10
-	}
-	buf[i] = byte(val + '0')
-	return buf[i:]
-}
-
-// An errorString represents a runtime error described by a single string.
-type errorString string
-
-func (e errorString) RuntimeError() {}
-
-func (e errorString) Error() string {
-	return "runtime error: " + string(e)
-}
-
-type errorAddressString struct {
-	msg  string  // error message
-	addr uintptr // memory address where the error occurred
-}
-
-func (e errorAddressString) RuntimeError() {}
-
-func (e errorAddressString) Error() string {
-	return "runtime error: " + e.msg
-}
-
-// Addr returns the memory address where a fault occurred.
-// The address provided is best-effort.
-// The veracity of the result may depend on the platform.
-// Errors providing this method will only be returned as
-// a result of using runtime/debug.SetPanicOnFault.
-func (e errorAddressString) Addr() uintptr {
-	return e.addr
-}
-
-// plainError represents a runtime error described a string without
-// the prefix "runtime error: " after invoking errorString.Error().
-// See Issue #14965.
-type plainError string
-
-func (e plainError) RuntimeError() {}
-
-func (e plainError) Error() string {
-	return string(e)
-}
-
-// A boundsError represents an indexing or slicing operation gone wrong.
-type boundsError struct {
-	x int64
-	y int
-	// Values in an index or slice expression can be signed or unsigned.
-	// That means we'd need 65 bits to encode all possible indexes, from -2^63 to 2^64-1.
-	// Instead, we keep track of whether x should be interpreted as signed or unsigned.
-	// y is known to be nonnegative and to fit in an int.
-	signed bool
-	code   boundsErrorCode
-}
-
-type boundsErrorCode uint8
-
-const (
-	boundsIndex boundsErrorCode = iota // s[x], 0 <= x < len(s) failed
-
-	boundsSliceAlen // s[?:x], 0 <= x <= len(s) failed
-	boundsSliceAcap // s[?:x], 0 <= x <= cap(s) failed
-	boundsSliceB    // s[x:y], 0 <= x <= y failed (but boundsSliceA didn't happen)
-
-	boundsSlice3Alen // s[?:?:x], 0 <= x <= len(s) failed
-	boundsSlice3Acap // s[?:?:x], 0 <= x <= cap(s) failed
-	boundsSlice3B    // s[?:x:y], 0 <= x <= y failed (but boundsSlice3A didn't happen)
-	boundsSlice3C    // s[x:y:?], 0 <= x <= y failed (but boundsSlice3A/B didn't happen)
-
-	boundsConvert // (*[x]T)(s), 0 <= x <= len(s) failed
-	// Note: in the above, len(s) and cap(s) are stored in y
-)
-
-// boundsErrorFmts provide error text for various out-of-bounds panics.
-// Note: if you change these strings, you should adjust the size of the buffer
-// in boundsError.Error below as well.
-var boundsErrorFmts = [...]string{
-	boundsIndex:      "index out of range [%x] with length %y",
-	boundsSliceAlen:  "slice bounds out of range [:%x] with length %y",
-	boundsSliceAcap:  "slice bounds out of range [:%x] with capacity %y",
-	boundsSliceB:     "slice bounds out of range [%x:%y]",
-	boundsSlice3Alen: "slice bounds out of range [::%x] with length %y",
-	boundsSlice3Acap: "slice bounds out of range [::%x] with capacity %y",
-	boundsSlice3B:    "slice bounds out of range [:%x:%y]",
-	boundsSlice3C:    "slice bounds out of range [%x:%y:]",
-	boundsConvert:    "cannot convert slice with length %y to pointer to array with length %x",
-}
-
-// boundsNegErrorFmts are overriding formats if x is negative. In this case there's no need to report y.
-var boundsNegErrorFmts = [...]string{
-	boundsIndex:      "index out of range [%x]",
-	boundsSliceAlen:  "slice bounds out of range [:%x]",
-	boundsSliceAcap:  "slice bounds out of range [:%x]",
-	boundsSliceB:     "slice bounds out of range [%x:]",
-	boundsSlice3Alen: "slice bounds out of range [::%x]",
-	boundsSlice3Acap: "slice bounds out of range [::%x]",
-	boundsSlice3B:    "slice bounds out of range [:%x:]",
-	boundsSlice3C:    "slice bounds out of range [%x::]",
-}
-
-func (e boundsError) RuntimeError() {}
-
-func appendIntStr(b []byte, v int64, signed bool) []byte {
-	if signed && v < 0 {
-		b = append(b, '-')
-		v = -v
-	}
-	var buf [20]byte
-	b = append(b, itoa(buf[:], uint64(v))...)
-	return b
-}
-
-func (e boundsError) Error() string {
-	fmt := boundsErrorFmts[e.code]
-	if e.signed && e.x < 0 {
-		fmt = boundsNegErrorFmts[e.code]
-	}
-	// max message length is 99: "runtime error: slice bounds out of range [::%x] with capacity %y"
-	// x can be at most 20 characters. y can be at most 19.
-	b := make([]byte, 0, 100)
-	b = append(b, "runtime error: "...)
-	for i := 0; i < len(fmt); i++ {
-		c := fmt[i]
-		if c != '%' {
-			b = append(b, c)
-			continue
-		}
-		i++
-		switch fmt[i] {
-		case 'x':
-			b = appendIntStr(b, e.x, e.signed)
-		case 'y':
-			b = appendIntStr(b, int64(e.y), true)
-		}
-	}
-	return string(b)
-}
-
-type stringer interface {
-	String() string
-}
-
-// printany prints an argument passed to panic.
-// If panic is called with a value that has a String or Error method,
-// it has already been converted into a string by preprintpanics.
-func printany(i any) {
-	switch v := i.(type) {
-	case nil:
-		print("nil")
-	case bool:
-		print(v)
-	case int:
-		print(v)
-	case int8:
-		print(v)
-	case int16:
-		print(v)
-	case int32:
-		print(v)
-	case int64:
-		print(v)
-	case uint:
-		print(v)
-	case uint8:
-		print(v)
-	case uint16:
-		print(v)
-	case uint32:
-		print(v)
-	case uint64:
-		print(v)
-	case uintptr:
-		print(v)
-	case float32:
-		print(v)
-	case float64:
-		print(v)
-	case complex64:
-		print(v)
-	case complex128:
-		print(v)
-	case string:
-		print(v)
-	default:
-		printanycustomtype(i)
-	}
-}
-
-func printanycustomtype(i any) {
-	eface := efaceOf(&i)
-	typestring := eface._type.string()
-
-	switch eface._type.kind {
-	case kindString:
-		print(typestring, `("`, *(*string)(eface.data), `")`)
-	case kindBool:
-		print(typestring, "(", *(*bool)(eface.data), ")")
-	case kindInt:
-		print(typestring, "(", *(*int)(eface.data), ")")
-	case kindInt8:
-		print(typestring, "(", *(*int8)(eface.data), ")")
-	case kindInt16:
-		print(typestring, "(", *(*int16)(eface.data), ")")
-	case kindInt32:
-		print(typestring, "(", *(*int32)(eface.data), ")")
-	case kindInt64:
-		print(typestring, "(", *(*int64)(eface.data), ")")
-	case kindUint:
-		print(typestring, "(", *(*uint)(eface.data), ")")
-	case kindUint8:
-		print(typestring, "(", *(*uint8)(eface.data), ")")
-	case kindUint16:
-		print(typestring, "(", *(*uint16)(eface.data), ")")
-	case kindUint32:
-		print(typestring, "(", *(*uint32)(eface.data), ")")
-	case kindUint64:
-		print(typestring, "(", *(*uint64)(eface.data), ")")
-	case kindUintptr:
-		print(typestring, "(", *(*uintptr)(eface.data), ")")
-	case kindFloat32:
-		print(typestring, "(", *(*float32)(eface.data), ")")
-	case kindFloat64:
-		print(typestring, "(", *(*float64)(eface.data), ")")
-	case kindComplex64:
-		print(typestring, *(*complex64)(eface.data))
-	case kindComplex128:
-		print(typestring, *(*complex128)(eface.data))
-	default:
-		print("(", typestring, ") ", eface.data)
-	}
-}
-
-// panicwrap generates a panic for a call to a wrapped value method
-// with a nil pointer receiver.
-//
-// It is called from the generated wrapper code.
-func panicwrap() {
-	pc := getcallerpc()
-	name := funcname(findfunc(pc))
-	// name is something like "main.(*T).F".
-	// We want to extract pkg ("main"), typ ("T"), and meth ("F").
-	// Do it by finding the parens.
-	i := bytealg.IndexByteString(name, '(')
-	if i < 0 {
-		throw("panicwrap: no ( in " + name)
-	}
-	pkg := name[:i-1]
-	if i+2 >= len(name) || name[i-1:i+2] != ".(*" {
-		throw("panicwrap: unexpected string after package name: " + name)
-	}
-	name = name[i+2:]
-	i = bytealg.IndexByteString(name, ')')
-	if i < 0 {
-		throw("panicwrap: no ) in " + name)
-	}
-	if i+2 >= len(name) || name[i:i+2] != ")." {
-		throw("panicwrap: unexpected string after type name: " + name)
-	}
-	typ := name[:i]
-	meth := name[i+2:]
-	panic(plainError("value method " + pkg + "." + typ + "." + meth + " called using nil *" + typ + " pointer"))
-}
diff --git a/contrib/go/_std_1.18/src/runtime/extern.go b/contrib/go/_std_1.18/src/runtime/extern.go
deleted file mode 100644
index f1f6ea5123..0000000000
--- a/contrib/go/_std_1.18/src/runtime/extern.go
+++ /dev/null
@@ -1,275 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-/*
-Package runtime contains operations that interact with Go's runtime system,
-such as functions to control goroutines. It also includes the low-level type information
-used by the reflect package; see reflect's documentation for the programmable
-interface to the run-time type system.
-
-Environment Variables
-
-The following environment variables ($name or %name%, depending on the host
-operating system) control the run-time behavior of Go programs. The meanings
-and use may change from release to release.
-
-The GOGC variable sets the initial garbage collection target percentage.
-A collection is triggered when the ratio of freshly allocated data to live data
-remaining after the previous collection reaches this percentage. The default
-is GOGC=100. Setting GOGC=off disables the garbage collector entirely.
-The runtime/debug package's SetGCPercent function allows changing this
-percentage at run time. See https://golang.org/pkg/runtime/debug/#SetGCPercent.
-
-The GODEBUG variable controls debugging variables within the runtime.
-It is a comma-separated list of name=val pairs setting these named variables:
-
-	allocfreetrace: setting allocfreetrace=1 causes every allocation to be
-	profiled and a stack trace printed on each object's allocation and free.
-
-	clobberfree: setting clobberfree=1 causes the garbage collector to
-	clobber the memory content of an object with bad content when it frees
-	the object.
-
-	cgocheck: setting cgocheck=0 disables all checks for packages
-	using cgo to incorrectly pass Go pointers to non-Go code.
-	Setting cgocheck=1 (the default) enables relatively cheap
-	checks that may miss some errors.  Setting cgocheck=2 enables
-	expensive checks that should not miss any errors, but will
-	cause your program to run slower.
-
-	efence: setting efence=1 causes the allocator to run in a mode
-	where each object is allocated on a unique page and addresses are
-	never recycled.
-
-	gccheckmark: setting gccheckmark=1 enables verification of the
-	garbage collector's concurrent mark phase by performing a
-	second mark pass while the world is stopped.  If the second
-	pass finds a reachable object that was not found by concurrent
-	mark, the garbage collector will panic.
-
-	gcpacertrace: setting gcpacertrace=1 causes the garbage collector to
-	print information about the internal state of the concurrent pacer.
-
-	gcshrinkstackoff: setting gcshrinkstackoff=1 disables moving goroutines
-	onto smaller stacks. In this mode, a goroutine's stack can only grow.
-
-	gcstoptheworld: setting gcstoptheworld=1 disables concurrent garbage collection,
-	making every garbage collection a stop-the-world event. Setting gcstoptheworld=2
-	also disables concurrent sweeping after the garbage collection finishes.
-
-	gctrace: setting gctrace=1 causes the garbage collector to emit a single line to standard
-	error at each collection, summarizing the amount of memory collected and the
-	length of the pause. The format of this line is subject to change.
-	Currently, it is:
-		gc # @#s #%: #+#+# ms clock, #+#/#/#+# ms cpu, #->#-># MB, # MB goal, # P
-	where the fields are as follows:
-		gc #        the GC number, incremented at each GC
-		@#s         time in seconds since program start
-		#%          percentage of time spent in GC since program start
-		#+...+#     wall-clock/CPU times for the phases of the GC
-		#->#-># MB  heap size at GC start, at GC end, and live heap
-		# MB goal   goal heap size
-		# P         number of processors used
-	The phases are stop-the-world (STW) sweep termination, concurrent
-	mark and scan, and STW mark termination. The CPU times
-	for mark/scan are broken down in to assist time (GC performed in
-	line with allocation), background GC time, and idle GC time.
-	If the line ends with "(forced)", this GC was forced by a
-	runtime.GC() call.
-
-	harddecommit: setting harddecommit=1 causes memory that is returned to the OS to
-	also have protections removed on it. This is the only mode of operation on Windows,
-	but is helpful in debugging scavenger-related issues on other platforms. Currently,
-	only supported on Linux.
-
-	inittrace: setting inittrace=1 causes the runtime to emit a single line to standard
-	error for each package with init work, summarizing the execution time and memory
-	allocation. No information is printed for inits executed as part of plugin loading
-	and for packages without both user defined and compiler generated init work.
-	The format of this line is subject to change. Currently, it is:
-		init # @#ms, # ms clock, # bytes, # allocs
-	where the fields are as follows:
-		init #      the package name
-		@# ms       time in milliseconds when the init started since program start
-		# clock     wall-clock time for package initialization work
-		# bytes     memory allocated on the heap
-		# allocs    number of heap allocations
-
-	madvdontneed: setting madvdontneed=0 will use MADV_FREE
-	instead of MADV_DONTNEED on Linux when returning memory to the
-	kernel. This is more efficient, but means RSS numbers will
-	drop only when the OS is under memory pressure.
-
-	memprofilerate: setting memprofilerate=X will update the value of runtime.MemProfileRate.
-	When set to 0 memory profiling is disabled.  Refer to the description of
-	MemProfileRate for the default value.
-
-	invalidptr: invalidptr=1 (the default) causes the garbage collector and stack
-	copier to crash the program if an invalid pointer value (for example, 1)
-	is found in a pointer-typed location. Setting invalidptr=0 disables this check.
-	This should only be used as a temporary workaround to diagnose buggy code.
-	The real fix is to not store integers in pointer-typed locations.
-
-	sbrk: setting sbrk=1 replaces the memory allocator and garbage collector
-	with a trivial allocator that obtains memory from the operating system and
-	never reclaims any memory.
-
-	scavtrace: setting scavtrace=1 causes the runtime to emit a single line to standard
-	error, roughly once per GC cycle, summarizing the amount of work done by the
-	scavenger as well as the total amount of memory returned to the operating system
-	and an estimate of physical memory utilization. The format of this line is subject
-	to change, but currently it is:
-		scav # # KiB work, # KiB total, #% util
-	where the fields are as follows:
-		scav #       the scavenge cycle number
-		# KiB work   the amount of memory returned to the OS since the last line
-		# KiB total  the total amount of memory returned to the OS
-		#% util      the fraction of all unscavenged memory which is in-use
-	If the line ends with "(forced)", then scavenging was forced by a
-	debug.FreeOSMemory() call.
-
-	scheddetail: setting schedtrace=X and scheddetail=1 causes the scheduler to emit
-	detailed multiline info every X milliseconds, describing state of the scheduler,
-	processors, threads and goroutines.
-
-	schedtrace: setting schedtrace=X causes the scheduler to emit a single line to standard
-	error every X milliseconds, summarizing the scheduler state.
-
-	tracebackancestors: setting tracebackancestors=N extends tracebacks with the stacks at
-	which goroutines were created, where N limits the number of ancestor goroutines to
-	report. This also extends the information returned by runtime.Stack. Ancestor's goroutine
-	IDs will refer to the ID of the goroutine at the time of creation; it's possible for this
-	ID to be reused for another goroutine. Setting N to 0 will report no ancestry information.
-
-	asyncpreemptoff: asyncpreemptoff=1 disables signal-based
-	asynchronous goroutine preemption. This makes some loops
-	non-preemptible for long periods, which may delay GC and
-	goroutine scheduling. This is useful for debugging GC issues
-	because it also disables the conservative stack scanning used
-	for asynchronously preempted goroutines.
-
-The net and net/http packages also refer to debugging variables in GODEBUG.
-See the documentation for those packages for details.
-
-The GOMAXPROCS variable limits the number of operating system threads that
-can execute user-level Go code simultaneously. There is no limit to the number of threads
-that can be blocked in system calls on behalf of Go code; those do not count against
-the GOMAXPROCS limit. This package's GOMAXPROCS function queries and changes
-the limit.
-
-The GORACE variable configures the race detector, for programs built using -race.
-See https://golang.org/doc/articles/race_detector.html for details.
-
-The GOTRACEBACK variable controls the amount of output generated when a Go
-program fails due to an unrecovered panic or an unexpected runtime condition.
-By default, a failure prints a stack trace for the current goroutine,
-eliding functions internal to the run-time system, and then exits with exit code 2.
-The failure prints stack traces for all goroutines if there is no current goroutine
-or the failure is internal to the run-time.
-GOTRACEBACK=none omits the goroutine stack traces entirely.
-GOTRACEBACK=single (the default) behaves as described above.
-GOTRACEBACK=all adds stack traces for all user-created goroutines.
-GOTRACEBACK=system is like ``all'' but adds stack frames for run-time functions
-and shows goroutines created internally by the run-time.
-GOTRACEBACK=crash is like ``system'' but crashes in an operating system-specific
-manner instead of exiting. For example, on Unix systems, the crash raises
-SIGABRT to trigger a core dump.
-For historical reasons, the GOTRACEBACK settings 0, 1, and 2 are synonyms for
-none, all, and system, respectively.
-The runtime/debug package's SetTraceback function allows increasing the
-amount of output at run time, but it cannot reduce the amount below that
-specified by the environment variable.
-See https://golang.org/pkg/runtime/debug/#SetTraceback.
-
-The GOARCH, GOOS, GOPATH, and GOROOT environment variables complete
-the set of Go environment variables. They influence the building of Go programs
-(see https://golang.org/cmd/go and https://golang.org/pkg/go/build).
-GOARCH, GOOS, and GOROOT are recorded at compile time and made available by
-constants or functions in this package, but they do not influence the execution
-of the run-time system.
-*/
-package runtime
-
-import (
-	"internal/goarch"
-	"internal/goos"
-)
-
-// Caller reports file and line number information about function invocations on
-// the calling goroutine's stack. The argument skip is the number of stack frames
-// to ascend, with 0 identifying the caller of Caller.  (For historical reasons the
-// meaning of skip differs between Caller and Callers.) The return values report the
-// program counter, file name, and line number within the file of the corresponding
-// call. The boolean ok is false if it was not possible to recover the information.
-func Caller(skip int) (pc uintptr, file string, line int, ok bool) {
-	rpc := make([]uintptr, 1)
-	n := callers(skip+1, rpc[:])
-	if n < 1 {
-		return
-	}
-	frame, _ := CallersFrames(rpc).Next()
-	return frame.PC, frame.File, frame.Line, frame.PC != 0
-}
-
-// Callers fills the slice pc with the return program counters of function invocations
-// on the calling goroutine's stack. The argument skip is the number of stack frames
-// to skip before recording in pc, with 0 identifying the frame for Callers itself and
-// 1 identifying the caller of Callers.
-// It returns the number of entries written to pc.
-//
-// To translate these PCs into symbolic information such as function
-// names and line numbers, use CallersFrames. CallersFrames accounts
-// for inlined functions and adjusts the return program counters into
-// call program counters. Iterating over the returned slice of PCs
-// directly is discouraged, as is using FuncForPC on any of the
-// returned PCs, since these cannot account for inlining or return
-// program counter adjustment.
-func Callers(skip int, pc []uintptr) int {
-	// runtime.callers uses pc.array==nil as a signal
-	// to print a stack trace. Pick off 0-length pc here
-	// so that we don't let a nil pc slice get to it.
-	if len(pc) == 0 {
-		return 0
-	}
-	return callers(skip, pc)
-}
-
-var defaultGOROOT string // set by cmd/link
-
-// GOROOT returns the root of the Go tree. It uses the
-// GOROOT environment variable, if set at process start,
-// or else the root used during the Go build.
-func GOROOT() string {
-	s := gogetenv("GOROOT")
-	if s != "" {
-		return s
-	}
-	return defaultGOROOT
-}
-
-// buildVersion is the Go tree's version string at build time.
-//
-// If any GOEXPERIMENTs are set to non-default values, it will include
-// "X:<GOEXPERIMENT>".
-//
-// This is set by the linker.
-//
-// This is accessed by "go version <binary>".
-var buildVersion string
-
-// Version returns the Go tree's version string.
-// It is either the commit hash and date at the time of the build or,
-// when possible, a release tag like "go1.3".
-func Version() string {
-	return buildVersion
-}
-
-// GOOS is the running program's operating system target:
-// one of darwin, freebsd, linux, and so on.
-// To view possible combinations of GOOS and GOARCH, run "go tool dist list".
-const GOOS string = goos.GOOS
-
-// GOARCH is the running program's architecture target:
-// one of 386, amd64, arm, s390x, and so on.
-const GOARCH string = goarch.GOARCH
diff --git a/contrib/go/_std_1.18/src/runtime/float.go b/contrib/go/_std_1.18/src/runtime/float.go
deleted file mode 100644
index 459e58dd7e..0000000000
--- a/contrib/go/_std_1.18/src/runtime/float.go
+++ /dev/null
@@ -1,53 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import "unsafe"
-
-var inf = float64frombits(0x7FF0000000000000)
-
-// isNaN reports whether f is an IEEE 754 ``not-a-number'' value.
-func isNaN(f float64) (is bool) {
-	// IEEE 754 says that only NaNs satisfy f != f.
-	return f != f
-}
-
-// isFinite reports whether f is neither NaN nor an infinity.
-func isFinite(f float64) bool {
-	return !isNaN(f - f)
-}
-
-// isInf reports whether f is an infinity.
-func isInf(f float64) bool {
-	return !isNaN(f) && !isFinite(f)
-}
-
-// Abs returns the absolute value of x.
-//
-// Special cases are:
-//	Abs(±Inf) = +Inf
-//	Abs(NaN) = NaN
-func abs(x float64) float64 {
-	const sign = 1 << 63
-	return float64frombits(float64bits(x) &^ sign)
-}
-
-// copysign returns a value with the magnitude
-// of x and the sign of y.
-func copysign(x, y float64) float64 {
-	const sign = 1 << 63
-	return float64frombits(float64bits(x)&^sign | float64bits(y)&sign)
-}
-
-// Float64bits returns the IEEE 754 binary representation of f.
-func float64bits(f float64) uint64 {
-	return *(*uint64)(unsafe.Pointer(&f))
-}
-
-// Float64frombits returns the floating point number corresponding
-// the IEEE 754 binary representation b.
-func float64frombits(b uint64) float64 {
-	return *(*float64)(unsafe.Pointer(&b))
-}
diff --git a/contrib/go/_std_1.18/src/runtime/hash64.go b/contrib/go/_std_1.18/src/runtime/hash64.go
deleted file mode 100644
index f773eb929c..0000000000
--- a/contrib/go/_std_1.18/src/runtime/hash64.go
+++ /dev/null
@@ -1,92 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Hashing algorithm inspired by
-// wyhash: https://github.com/wangyi-fudan/wyhash
-
-//go:build amd64 || arm64 || mips64 || mips64le || ppc64 || ppc64le || riscv64 || s390x || wasm
-
-package runtime
-
-import (
-	"runtime/internal/math"
-	"unsafe"
-)
-
-const (
-	m1 = 0xa0761d6478bd642f
-	m2 = 0xe7037ed1a0b428db
-	m3 = 0x8ebc6af09c88c6e3
-	m4 = 0x589965cc75374cc3
-	m5 = 0x1d8e4e27c47d124f
-)
-
-func memhashFallback(p unsafe.Pointer, seed, s uintptr) uintptr {
-	var a, b uintptr
-	seed ^= hashkey[0] ^ m1
-	switch {
-	case s == 0:
-		return seed
-	case s < 4:
-		a = uintptr(*(*byte)(p))
-		a |= uintptr(*(*byte)(add(p, s>>1))) << 8
-		a |= uintptr(*(*byte)(add(p, s-1))) << 16
-	case s == 4:
-		a = r4(p)
-		b = a
-	case s < 8:
-		a = r4(p)
-		b = r4(add(p, s-4))
-	case s == 8:
-		a = r8(p)
-		b = a
-	case s <= 16:
-		a = r8(p)
-		b = r8(add(p, s-8))
-	default:
-		l := s
-		if l > 48 {
-			seed1 := seed
-			seed2 := seed
-			for ; l > 48; l -= 48 {
-				seed = mix(r8(p)^m2, r8(add(p, 8))^seed)
-				seed1 = mix(r8(add(p, 16))^m3, r8(add(p, 24))^seed1)
-				seed2 = mix(r8(add(p, 32))^m4, r8(add(p, 40))^seed2)
-				p = add(p, 48)
-			}
-			seed ^= seed1 ^ seed2
-		}
-		for ; l > 16; l -= 16 {
-			seed = mix(r8(p)^m2, r8(add(p, 8))^seed)
-			p = add(p, 16)
-		}
-		a = r8(add(p, l-16))
-		b = r8(add(p, l-8))
-	}
-
-	return mix(m5^s, mix(a^m2, b^seed))
-}
-
-func memhash32Fallback(p unsafe.Pointer, seed uintptr) uintptr {
-	a := r4(p)
-	return mix(m5^4, mix(a^m2, a^seed^hashkey[0]^m1))
-}
-
-func memhash64Fallback(p unsafe.Pointer, seed uintptr) uintptr {
-	a := r8(p)
-	return mix(m5^8, mix(a^m2, a^seed^hashkey[0]^m1))
-}
-
-func mix(a, b uintptr) uintptr {
-	hi, lo := math.Mul64(uint64(a), uint64(b))
-	return uintptr(hi ^ lo)
-}
-
-func r4(p unsafe.Pointer) uintptr {
-	return uintptr(readUnaligned32(p))
-}
-
-func r8(p unsafe.Pointer) uintptr {
-	return uintptr(readUnaligned64(p))
-}
diff --git a/contrib/go/_std_1.18/src/runtime/heapdump.go b/contrib/go/_std_1.18/src/runtime/heapdump.go
deleted file mode 100644
index 871637a09e..0000000000
--- a/contrib/go/_std_1.18/src/runtime/heapdump.go
+++ /dev/null
@@ -1,757 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Implementation of runtime/debug.WriteHeapDump. Writes all
-// objects in the heap plus additional info (roots, threads,
-// finalizers, etc.) to a file.
-
-// The format of the dumped file is described at
-// https://golang.org/s/go15heapdump.
-
-package runtime
-
-import (
-	"internal/goarch"
-	"unsafe"
-)
-
-//go:linkname runtime_debug_WriteHeapDump runtime/debug.WriteHeapDump
-func runtime_debug_WriteHeapDump(fd uintptr) {
-	stopTheWorld("write heap dump")
-
-	// Keep m on this G's stack instead of the system stack.
-	// Both readmemstats_m and writeheapdump_m have pretty large
-	// peak stack depths and we risk blowing the system stack.
-	// This is safe because the world is stopped, so we don't
-	// need to worry about anyone shrinking and therefore moving
-	// our stack.
-	var m MemStats
-	systemstack(func() {
-		// Call readmemstats_m here instead of deeper in
-		// writeheapdump_m because we might blow the system stack
-		// otherwise.
-		readmemstats_m(&m)
-		writeheapdump_m(fd, &m)
-	})
-
-	startTheWorld()
-}
-
-const (
-	fieldKindEol       = 0
-	fieldKindPtr       = 1
-	fieldKindIface     = 2
-	fieldKindEface     = 3
-	tagEOF             = 0
-	tagObject          = 1
-	tagOtherRoot       = 2
-	tagType            = 3
-	tagGoroutine       = 4
-	tagStackFrame      = 5
-	tagParams          = 6
-	tagFinalizer       = 7
-	tagItab            = 8
-	tagOSThread        = 9
-	tagMemStats        = 10
-	tagQueuedFinalizer = 11
-	tagData            = 12
-	tagBSS             = 13
-	tagDefer           = 14
-	tagPanic           = 15
-	tagMemProf         = 16
-	tagAllocSample     = 17
-)
-
-var dumpfd uintptr // fd to write the dump to.
-var tmpbuf []byte
-
-// buffer of pending write data
-const (
-	bufSize = 4096
-)
-
-var buf [bufSize]byte
-var nbuf uintptr
-
-func dwrite(data unsafe.Pointer, len uintptr) {
-	if len == 0 {
-		return
-	}
-	if nbuf+len <= bufSize {
-		copy(buf[nbuf:], (*[bufSize]byte)(data)[:len])
-		nbuf += len
-		return
-	}
-
-	write(dumpfd, unsafe.Pointer(&buf), int32(nbuf))
-	if len >= bufSize {
-		write(dumpfd, data, int32(len))
-		nbuf = 0
-	} else {
-		copy(buf[:], (*[bufSize]byte)(data)[:len])
-		nbuf = len
-	}
-}
-
-func dwritebyte(b byte) {
-	dwrite(unsafe.Pointer(&b), 1)
-}
-
-func flush() {
-	write(dumpfd, unsafe.Pointer(&buf), int32(nbuf))
-	nbuf = 0
-}
-
-// Cache of types that have been serialized already.
-// We use a type's hash field to pick a bucket.
-// Inside a bucket, we keep a list of types that
-// have been serialized so far, most recently used first.
-// Note: when a bucket overflows we may end up
-// serializing a type more than once. That's ok.
-const (
-	typeCacheBuckets = 256
-	typeCacheAssoc   = 4
-)
-
-type typeCacheBucket struct {
-	t [typeCacheAssoc]*_type
-}
-
-var typecache [typeCacheBuckets]typeCacheBucket
-
-// dump a uint64 in a varint format parseable by encoding/binary
-func dumpint(v uint64) {
-	var buf [10]byte
-	var n int
-	for v >= 0x80 {
-		buf[n] = byte(v | 0x80)
-		n++
-		v >>= 7
-	}
-	buf[n] = byte(v)
-	n++
-	dwrite(unsafe.Pointer(&buf), uintptr(n))
-}
-
-func dumpbool(b bool) {
-	if b {
-		dumpint(1)
-	} else {
-		dumpint(0)
-	}
-}
-
-// dump varint uint64 length followed by memory contents
-func dumpmemrange(data unsafe.Pointer, len uintptr) {
-	dumpint(uint64(len))
-	dwrite(data, len)
-}
-
-func dumpslice(b []byte) {
-	dumpint(uint64(len(b)))
-	if len(b) > 0 {
-		dwrite(unsafe.Pointer(&b[0]), uintptr(len(b)))
-	}
-}
-
-func dumpstr(s string) {
-	sp := stringStructOf(&s)
-	dumpmemrange(sp.str, uintptr(sp.len))
-}
-
-// dump information for a type
-func dumptype(t *_type) {
-	if t == nil {
-		return
-	}
-
-	// If we've definitely serialized the type before,
-	// no need to do it again.
-	b := &typecache[t.hash&(typeCacheBuckets-1)]
-	if t == b.t[0] {
-		return
-	}
-	for i := 1; i < typeCacheAssoc; i++ {
-		if t == b.t[i] {
-			// Move-to-front
-			for j := i; j > 0; j-- {
-				b.t[j] = b.t[j-1]
-			}
-			b.t[0] = t
-			return
-		}
-	}
-
-	// Might not have been dumped yet. Dump it and
-	// remember we did so.
-	for j := typeCacheAssoc - 1; j > 0; j-- {
-		b.t[j] = b.t[j-1]
-	}
-	b.t[0] = t
-
-	// dump the type
-	dumpint(tagType)
-	dumpint(uint64(uintptr(unsafe.Pointer(t))))
-	dumpint(uint64(t.size))
-	if x := t.uncommon(); x == nil || t.nameOff(x.pkgpath).name() == "" {
-		dumpstr(t.string())
-	} else {
-		pkgpathstr := t.nameOff(x.pkgpath).name()
-		pkgpath := stringStructOf(&pkgpathstr)
-		namestr := t.name()
-		name := stringStructOf(&namestr)
-		dumpint(uint64(uintptr(pkgpath.len) + 1 + uintptr(name.len)))
-		dwrite(pkgpath.str, uintptr(pkgpath.len))
-		dwritebyte('.')
-		dwrite(name.str, uintptr(name.len))
-	}
-	dumpbool(t.kind&kindDirectIface == 0 || t.ptrdata != 0)
-}
-
-// dump an object
-func dumpobj(obj unsafe.Pointer, size uintptr, bv bitvector) {
-	dumpint(tagObject)
-	dumpint(uint64(uintptr(obj)))
-	dumpmemrange(obj, size)
-	dumpfields(bv)
-}
-
-func dumpotherroot(description string, to unsafe.Pointer) {
-	dumpint(tagOtherRoot)
-	dumpstr(description)
-	dumpint(uint64(uintptr(to)))
-}
-
-func dumpfinalizer(obj unsafe.Pointer, fn *funcval, fint *_type, ot *ptrtype) {
-	dumpint(tagFinalizer)
-	dumpint(uint64(uintptr(obj)))
-	dumpint(uint64(uintptr(unsafe.Pointer(fn))))
-	dumpint(uint64(uintptr(unsafe.Pointer(fn.fn))))
-	dumpint(uint64(uintptr(unsafe.Pointer(fint))))
-	dumpint(uint64(uintptr(unsafe.Pointer(ot))))
-}
-
-type childInfo struct {
-	// Information passed up from the callee frame about
-	// the layout of the outargs region.
-	argoff uintptr   // where the arguments start in the frame
-	arglen uintptr   // size of args region
-	args   bitvector // if args.n >= 0, pointer map of args region
-	sp     *uint8    // callee sp
-	depth  uintptr   // depth in call stack (0 == most recent)
-}
-
-// dump kinds & offsets of interesting fields in bv
-func dumpbv(cbv *bitvector, offset uintptr) {
-	for i := uintptr(0); i < uintptr(cbv.n); i++ {
-		if cbv.ptrbit(i) == 1 {
-			dumpint(fieldKindPtr)
-			dumpint(uint64(offset + i*goarch.PtrSize))
-		}
-	}
-}
-
-func dumpframe(s *stkframe, arg unsafe.Pointer) bool {
-	child := (*childInfo)(arg)
-	f := s.fn
-
-	// Figure out what we can about our stack map
-	pc := s.pc
-	pcdata := int32(-1) // Use the entry map at function entry
-	if pc != f.entry() {
-		pc--
-		pcdata = pcdatavalue(f, _PCDATA_StackMapIndex, pc, nil)
-	}
-	if pcdata == -1 {
-		// We do not have a valid pcdata value but there might be a
-		// stackmap for this function. It is likely that we are looking
-		// at the function prologue, assume so and hope for the best.
-		pcdata = 0
-	}
-	stkmap := (*stackmap)(funcdata(f, _FUNCDATA_LocalsPointerMaps))
-
-	var bv bitvector
-	if stkmap != nil && stkmap.n > 0 {
-		bv = stackmapdata(stkmap, pcdata)
-	} else {
-		bv.n = -1
-	}
-
-	// Dump main body of stack frame.
-	dumpint(tagStackFrame)
-	dumpint(uint64(s.sp))                              // lowest address in frame
-	dumpint(uint64(child.depth))                       // # of frames deep on the stack
-	dumpint(uint64(uintptr(unsafe.Pointer(child.sp)))) // sp of child, or 0 if bottom of stack
-	dumpmemrange(unsafe.Pointer(s.sp), s.fp-s.sp)      // frame contents
-	dumpint(uint64(f.entry()))
-	dumpint(uint64(s.pc))
-	dumpint(uint64(s.continpc))
-	name := funcname(f)
-	if name == "" {
-		name = "unknown function"
-	}
-	dumpstr(name)
-
-	// Dump fields in the outargs section
-	if child.args.n >= 0 {
-		dumpbv(&child.args, child.argoff)
-	} else {
-		// conservative - everything might be a pointer
-		for off := child.argoff; off < child.argoff+child.arglen; off += goarch.PtrSize {
-			dumpint(fieldKindPtr)
-			dumpint(uint64(off))
-		}
-	}
-
-	// Dump fields in the local vars section
-	if stkmap == nil {
-		// No locals information, dump everything.
-		for off := child.arglen; off < s.varp-s.sp; off += goarch.PtrSize {
-			dumpint(fieldKindPtr)
-			dumpint(uint64(off))
-		}
-	} else if stkmap.n < 0 {
-		// Locals size information, dump just the locals.
-		size := uintptr(-stkmap.n)
-		for off := s.varp - size - s.sp; off < s.varp-s.sp; off += goarch.PtrSize {
-			dumpint(fieldKindPtr)
-			dumpint(uint64(off))
-		}
-	} else if stkmap.n > 0 {
-		// Locals bitmap information, scan just the pointers in
-		// locals.
-		dumpbv(&bv, s.varp-uintptr(bv.n)*goarch.PtrSize-s.sp)
-	}
-	dumpint(fieldKindEol)
-
-	// Record arg info for parent.
-	child.argoff = s.argp - s.fp
-	child.arglen = s.arglen
-	child.sp = (*uint8)(unsafe.Pointer(s.sp))
-	child.depth++
-	stkmap = (*stackmap)(funcdata(f, _FUNCDATA_ArgsPointerMaps))
-	if stkmap != nil {
-		child.args = stackmapdata(stkmap, pcdata)
-	} else {
-		child.args.n = -1
-	}
-	return true
-}
-
-func dumpgoroutine(gp *g) {
-	var sp, pc, lr uintptr
-	if gp.syscallsp != 0 {
-		sp = gp.syscallsp
-		pc = gp.syscallpc
-		lr = 0
-	} else {
-		sp = gp.sched.sp
-		pc = gp.sched.pc
-		lr = gp.sched.lr
-	}
-
-	dumpint(tagGoroutine)
-	dumpint(uint64(uintptr(unsafe.Pointer(gp))))
-	dumpint(uint64(sp))
-	dumpint(uint64(gp.goid))
-	dumpint(uint64(gp.gopc))
-	dumpint(uint64(readgstatus(gp)))
-	dumpbool(isSystemGoroutine(gp, false))
-	dumpbool(false) // isbackground
-	dumpint(uint64(gp.waitsince))
-	dumpstr(gp.waitreason.String())
-	dumpint(uint64(uintptr(gp.sched.ctxt)))
-	dumpint(uint64(uintptr(unsafe.Pointer(gp.m))))
-	dumpint(uint64(uintptr(unsafe.Pointer(gp._defer))))
-	dumpint(uint64(uintptr(unsafe.Pointer(gp._panic))))
-
-	// dump stack
-	var child childInfo
-	child.args.n = -1
-	child.arglen = 0
-	child.sp = nil
-	child.depth = 0
-	gentraceback(pc, sp, lr, gp, 0, nil, 0x7fffffff, dumpframe, noescape(unsafe.Pointer(&child)), 0)
-
-	// dump defer & panic records
-	for d := gp._defer; d != nil; d = d.link {
-		dumpint(tagDefer)
-		dumpint(uint64(uintptr(unsafe.Pointer(d))))
-		dumpint(uint64(uintptr(unsafe.Pointer(gp))))
-		dumpint(uint64(d.sp))
-		dumpint(uint64(d.pc))
-		fn := *(**funcval)(unsafe.Pointer(&d.fn))
-		dumpint(uint64(uintptr(unsafe.Pointer(fn))))
-		if d.fn == nil {
-			// d.fn can be nil for open-coded defers
-			dumpint(uint64(0))
-		} else {
-			dumpint(uint64(uintptr(unsafe.Pointer(fn.fn))))
-		}
-		dumpint(uint64(uintptr(unsafe.Pointer(d.link))))
-	}
-	for p := gp._panic; p != nil; p = p.link {
-		dumpint(tagPanic)
-		dumpint(uint64(uintptr(unsafe.Pointer(p))))
-		dumpint(uint64(uintptr(unsafe.Pointer(gp))))
-		eface := efaceOf(&p.arg)
-		dumpint(uint64(uintptr(unsafe.Pointer(eface._type))))
-		dumpint(uint64(uintptr(unsafe.Pointer(eface.data))))
-		dumpint(0) // was p->defer, no longer recorded
-		dumpint(uint64(uintptr(unsafe.Pointer(p.link))))
-	}
-}
-
-func dumpgs() {
-	assertWorldStopped()
-
-	// goroutines & stacks
-	forEachG(func(gp *g) {
-		status := readgstatus(gp) // The world is stopped so gp will not be in a scan state.
-		switch status {
-		default:
-			print("runtime: unexpected G.status ", hex(status), "\n")
-			throw("dumpgs in STW - bad status")
-		case _Gdead:
-			// ok
-		case _Grunnable,
-			_Gsyscall,
-			_Gwaiting:
-			dumpgoroutine(gp)
-		}
-	})
-}
-
-func finq_callback(fn *funcval, obj unsafe.Pointer, nret uintptr, fint *_type, ot *ptrtype) {
-	dumpint(tagQueuedFinalizer)
-	dumpint(uint64(uintptr(obj)))
-	dumpint(uint64(uintptr(unsafe.Pointer(fn))))
-	dumpint(uint64(uintptr(unsafe.Pointer(fn.fn))))
-	dumpint(uint64(uintptr(unsafe.Pointer(fint))))
-	dumpint(uint64(uintptr(unsafe.Pointer(ot))))
-}
-
-func dumproots() {
-	// To protect mheap_.allspans.
-	assertWorldStopped()
-
-	// TODO(mwhudson): dump datamask etc from all objects
-	// data segment
-	dumpint(tagData)
-	dumpint(uint64(firstmoduledata.data))
-	dumpmemrange(unsafe.Pointer(firstmoduledata.data), firstmoduledata.edata-firstmoduledata.data)
-	dumpfields(firstmoduledata.gcdatamask)
-
-	// bss segment
-	dumpint(tagBSS)
-	dumpint(uint64(firstmoduledata.bss))
-	dumpmemrange(unsafe.Pointer(firstmoduledata.bss), firstmoduledata.ebss-firstmoduledata.bss)
-	dumpfields(firstmoduledata.gcbssmask)
-
-	// mspan.types
-	for _, s := range mheap_.allspans {
-		if s.state.get() == mSpanInUse {
-			// Finalizers
-			for sp := s.specials; sp != nil; sp = sp.next {
-				if sp.kind != _KindSpecialFinalizer {
-					continue
-				}
-				spf := (*specialfinalizer)(unsafe.Pointer(sp))
-				p := unsafe.Pointer(s.base() + uintptr(spf.special.offset))
-				dumpfinalizer(p, spf.fn, spf.fint, spf.ot)
-			}
-		}
-	}
-
-	// Finalizer queue
-	iterate_finq(finq_callback)
-}
-
-// Bit vector of free marks.
-// Needs to be as big as the largest number of objects per span.
-var freemark [_PageSize / 8]bool
-
-func dumpobjs() {
-	// To protect mheap_.allspans.
-	assertWorldStopped()
-
-	for _, s := range mheap_.allspans {
-		if s.state.get() != mSpanInUse {
-			continue
-		}
-		p := s.base()
-		size := s.elemsize
-		n := (s.npages << _PageShift) / size
-		if n > uintptr(len(freemark)) {
-			throw("freemark array doesn't have enough entries")
-		}
-
-		for freeIndex := uintptr(0); freeIndex < s.nelems; freeIndex++ {
-			if s.isFree(freeIndex) {
-				freemark[freeIndex] = true
-			}
-		}
-
-		for j := uintptr(0); j < n; j, p = j+1, p+size {
-			if freemark[j] {
-				freemark[j] = false
-				continue
-			}
-			dumpobj(unsafe.Pointer(p), size, makeheapobjbv(p, size))
-		}
-	}
-}
-
-func dumpparams() {
-	dumpint(tagParams)
-	x := uintptr(1)
-	if *(*byte)(unsafe.Pointer(&x)) == 1 {
-		dumpbool(false) // little-endian ptrs
-	} else {
-		dumpbool(true) // big-endian ptrs
-	}
-	dumpint(goarch.PtrSize)
-	var arenaStart, arenaEnd uintptr
-	for i1 := range mheap_.arenas {
-		if mheap_.arenas[i1] == nil {
-			continue
-		}
-		for i, ha := range mheap_.arenas[i1] {
-			if ha == nil {
-				continue
-			}
-			base := arenaBase(arenaIdx(i1)<<arenaL1Shift | arenaIdx(i))
-			if arenaStart == 0 || base < arenaStart {
-				arenaStart = base
-			}
-			if base+heapArenaBytes > arenaEnd {
-				arenaEnd = base + heapArenaBytes
-			}
-		}
-	}
-	dumpint(uint64(arenaStart))
-	dumpint(uint64(arenaEnd))
-	dumpstr(goarch.GOARCH)
-	dumpstr(buildVersion)
-	dumpint(uint64(ncpu))
-}
-
-func itab_callback(tab *itab) {
-	t := tab._type
-	dumptype(t)
-	dumpint(tagItab)
-	dumpint(uint64(uintptr(unsafe.Pointer(tab))))
-	dumpint(uint64(uintptr(unsafe.Pointer(t))))
-}
-
-func dumpitabs() {
-	iterate_itabs(itab_callback)
-}
-
-func dumpms() {
-	for mp := allm; mp != nil; mp = mp.alllink {
-		dumpint(tagOSThread)
-		dumpint(uint64(uintptr(unsafe.Pointer(mp))))
-		dumpint(uint64(mp.id))
-		dumpint(mp.procid)
-	}
-}
-
-//go:systemstack
-func dumpmemstats(m *MemStats) {
-	assertWorldStopped()
-
-	// These ints should be identical to the exported
-	// MemStats structure and should be ordered the same
-	// way too.
-	dumpint(tagMemStats)
-	dumpint(m.Alloc)
-	dumpint(m.TotalAlloc)
-	dumpint(m.Sys)
-	dumpint(m.Lookups)
-	dumpint(m.Mallocs)
-	dumpint(m.Frees)
-	dumpint(m.HeapAlloc)
-	dumpint(m.HeapSys)
-	dumpint(m.HeapIdle)
-	dumpint(m.HeapInuse)
-	dumpint(m.HeapReleased)
-	dumpint(m.HeapObjects)
-	dumpint(m.StackInuse)
-	dumpint(m.StackSys)
-	dumpint(m.MSpanInuse)
-	dumpint(m.MSpanSys)
-	dumpint(m.MCacheInuse)
-	dumpint(m.MCacheSys)
-	dumpint(m.BuckHashSys)
-	dumpint(m.GCSys)
-	dumpint(m.OtherSys)
-	dumpint(m.NextGC)
-	dumpint(m.LastGC)
-	dumpint(m.PauseTotalNs)
-	for i := 0; i < 256; i++ {
-		dumpint(m.PauseNs[i])
-	}
-	dumpint(uint64(m.NumGC))
-}
-
-func dumpmemprof_callback(b *bucket, nstk uintptr, pstk *uintptr, size, allocs, frees uintptr) {
-	stk := (*[100000]uintptr)(unsafe.Pointer(pstk))
-	dumpint(tagMemProf)
-	dumpint(uint64(uintptr(unsafe.Pointer(b))))
-	dumpint(uint64(size))
-	dumpint(uint64(nstk))
-	for i := uintptr(0); i < nstk; i++ {
-		pc := stk[i]
-		f := findfunc(pc)
-		if !f.valid() {
-			var buf [64]byte
-			n := len(buf)
-			n--
-			buf[n] = ')'
-			if pc == 0 {
-				n--
-				buf[n] = '0'
-			} else {
-				for pc > 0 {
-					n--
-					buf[n] = "0123456789abcdef"[pc&15]
-					pc >>= 4
-				}
-			}
-			n--
-			buf[n] = 'x'
-			n--
-			buf[n] = '0'
-			n--
-			buf[n] = '('
-			dumpslice(buf[n:])
-			dumpstr("?")
-			dumpint(0)
-		} else {
-			dumpstr(funcname(f))
-			if i > 0 && pc > f.entry() {
-				pc--
-			}
-			file, line := funcline(f, pc)
-			dumpstr(file)
-			dumpint(uint64(line))
-		}
-	}
-	dumpint(uint64(allocs))
-	dumpint(uint64(frees))
-}
-
-func dumpmemprof() {
-	// To protect mheap_.allspans.
-	assertWorldStopped()
-
-	iterate_memprof(dumpmemprof_callback)
-	for _, s := range mheap_.allspans {
-		if s.state.get() != mSpanInUse {
-			continue
-		}
-		for sp := s.specials; sp != nil; sp = sp.next {
-			if sp.kind != _KindSpecialProfile {
-				continue
-			}
-			spp := (*specialprofile)(unsafe.Pointer(sp))
-			p := s.base() + uintptr(spp.special.offset)
-			dumpint(tagAllocSample)
-			dumpint(uint64(p))
-			dumpint(uint64(uintptr(unsafe.Pointer(spp.b))))
-		}
-	}
-}
-
-var dumphdr = []byte("go1.7 heap dump\n")
-
-func mdump(m *MemStats) {
-	assertWorldStopped()
-
-	// make sure we're done sweeping
-	for _, s := range mheap_.allspans {
-		if s.state.get() == mSpanInUse {
-			s.ensureSwept()
-		}
-	}
-	memclrNoHeapPointers(unsafe.Pointer(&typecache), unsafe.Sizeof(typecache))
-	dwrite(unsafe.Pointer(&dumphdr[0]), uintptr(len(dumphdr)))
-	dumpparams()
-	dumpitabs()
-	dumpobjs()
-	dumpgs()
-	dumpms()
-	dumproots()
-	dumpmemstats(m)
-	dumpmemprof()
-	dumpint(tagEOF)
-	flush()
-}
-
-func writeheapdump_m(fd uintptr, m *MemStats) {
-	assertWorldStopped()
-
-	_g_ := getg()
-	casgstatus(_g_.m.curg, _Grunning, _Gwaiting)
-	_g_.waitreason = waitReasonDumpingHeap
-
-	// Update stats so we can dump them.
-	// As a side effect, flushes all the mcaches so the mspan.freelist
-	// lists contain all the free objects.
-	updatememstats()
-
-	// Set dump file.
-	dumpfd = fd
-
-	// Call dump routine.
-	mdump(m)
-
-	// Reset dump file.
-	dumpfd = 0
-	if tmpbuf != nil {
-		sysFree(unsafe.Pointer(&tmpbuf[0]), uintptr(len(tmpbuf)), &memstats.other_sys)
-		tmpbuf = nil
-	}
-
-	casgstatus(_g_.m.curg, _Gwaiting, _Grunning)
-}
-
-// dumpint() the kind & offset of each field in an object.
-func dumpfields(bv bitvector) {
-	dumpbv(&bv, 0)
-	dumpint(fieldKindEol)
-}
-
-func makeheapobjbv(p uintptr, size uintptr) bitvector {
-	// Extend the temp buffer if necessary.
-	nptr := size / goarch.PtrSize
-	if uintptr(len(tmpbuf)) < nptr/8+1 {
-		if tmpbuf != nil {
-			sysFree(unsafe.Pointer(&tmpbuf[0]), uintptr(len(tmpbuf)), &memstats.other_sys)
-		}
-		n := nptr/8 + 1
-		p := sysAlloc(n, &memstats.other_sys)
-		if p == nil {
-			throw("heapdump: out of memory")
-		}
-		tmpbuf = (*[1 << 30]byte)(p)[:n]
-	}
-	// Convert heap bitmap to pointer bitmap.
-	for i := uintptr(0); i < nptr/8+1; i++ {
-		tmpbuf[i] = 0
-	}
-	i := uintptr(0)
-	hbits := heapBitsForAddr(p)
-	for ; i < nptr; i++ {
-		if !hbits.morePointers() {
-			break // end of object
-		}
-		if hbits.isPointer() {
-			tmpbuf[i/8] |= 1 << (i % 8)
-		}
-		hbits = hbits.next()
-	}
-	return bitvector{int32(i), &tmpbuf[0]}
-}
diff --git a/contrib/go/_std_1.18/src/runtime/histogram.go b/contrib/go/_std_1.18/src/runtime/histogram.go
deleted file mode 100644
index cd7e29a8c8..0000000000
--- a/contrib/go/_std_1.18/src/runtime/histogram.go
+++ /dev/null
@@ -1,170 +0,0 @@
-// Copyright 2020 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"runtime/internal/atomic"
-	"runtime/internal/sys"
-	"unsafe"
-)
-
-const (
-	// For the time histogram type, we use an HDR histogram.
-	// Values are placed in super-buckets based solely on the most
-	// significant set bit. Thus, super-buckets are power-of-2 sized.
-	// Values are then placed into sub-buckets based on the value of
-	// the next timeHistSubBucketBits most significant bits. Thus,
-	// sub-buckets are linear within a super-bucket.
-	//
-	// Therefore, the number of sub-buckets (timeHistNumSubBuckets)
-	// defines the error. This error may be computed as
-	// 1/timeHistNumSubBuckets*100%. For example, for 16 sub-buckets
-	// per super-bucket the error is approximately 6%.
-	//
-	// The number of super-buckets (timeHistNumSuperBuckets), on the
-	// other hand, defines the range. To reserve room for sub-buckets,
-	// bit timeHistSubBucketBits is the first bit considered for
-	// super-buckets, so super-bucket indices are adjusted accordingly.
-	//
-	// As an example, consider 45 super-buckets with 16 sub-buckets.
-	//
-	//    00110
-	//    ^----
-	//    │  ^
-	//    │  └---- Lowest 4 bits -> sub-bucket 6
-	//    └------- Bit 4 unset -> super-bucket 0
-	//
-	//    10110
-	//    ^----
-	//    │  ^
-	//    │  └---- Next 4 bits -> sub-bucket 6
-	//    └------- Bit 4 set -> super-bucket 1
-	//    100010
-	//    ^----^
-	//    │  ^ └-- Lower bits ignored
-	//    │  └---- Next 4 bits -> sub-bucket 1
-	//    └------- Bit 5 set -> super-bucket 2
-	//
-	// Following this pattern, super-bucket 44 will have the bit 47 set. We don't
-	// have any buckets for higher values, so the highest sub-bucket will
-	// contain values of 2^48-1 nanoseconds or approx. 3 days. This range is
-	// more than enough to handle durations produced by the runtime.
-	timeHistSubBucketBits   = 4
-	timeHistNumSubBuckets   = 1 << timeHistSubBucketBits
-	timeHistNumSuperBuckets = 45
-	timeHistTotalBuckets    = timeHistNumSuperBuckets*timeHistNumSubBuckets + 1
-)
-
-// timeHistogram represents a distribution of durations in
-// nanoseconds.
-//
-// The accuracy and range of the histogram is defined by the
-// timeHistSubBucketBits and timeHistNumSuperBuckets constants.
-//
-// It is an HDR histogram with exponentially-distributed
-// buckets and linearly distributed sub-buckets.
-//
-// Counts in the histogram are updated atomically, so it is safe
-// for concurrent use. It is also safe to read all the values
-// atomically.
-type timeHistogram struct {
-	counts [timeHistNumSuperBuckets * timeHistNumSubBuckets]uint64
-
-	// underflow counts all the times we got a negative duration
-	// sample. Because of how time works on some platforms, it's
-	// possible to measure negative durations. We could ignore them,
-	// but we record them anyway because it's better to have some
-	// signal that it's happening than just missing samples.
-	underflow uint64
-}
-
-// record adds the given duration to the distribution.
-//
-// Disallow preemptions and stack growths because this function
-// may run in sensitive locations.
-//go:nosplit
-func (h *timeHistogram) record(duration int64) {
-	if duration < 0 {
-		atomic.Xadd64(&h.underflow, 1)
-		return
-	}
-	// The index of the exponential bucket is just the index
-	// of the highest set bit adjusted for how many bits we
-	// use for the subbucket. Note that it's timeHistSubBucketsBits-1
-	// because we use the 0th bucket to hold values < timeHistNumSubBuckets.
-	var superBucket, subBucket uint
-	if duration >= timeHistNumSubBuckets {
-		// At this point, we know the duration value will always be
-		// at least timeHistSubBucketsBits long.
-		superBucket = uint(sys.Len64(uint64(duration))) - timeHistSubBucketBits
-		if superBucket*timeHistNumSubBuckets >= uint(len(h.counts)) {
-			// The bucket index we got is larger than what we support, so
-			// include this count in the highest bucket, which extends to
-			// infinity.
-			superBucket = timeHistNumSuperBuckets - 1
-			subBucket = timeHistNumSubBuckets - 1
-		} else {
-			// The linear subbucket index is just the timeHistSubBucketsBits
-			// bits after the top bit. To extract that value, shift down
-			// the duration such that we leave the top bit and the next bits
-			// intact, then extract the index.
-			subBucket = uint((duration >> (superBucket - 1)) % timeHistNumSubBuckets)
-		}
-	} else {
-		subBucket = uint(duration)
-	}
-	atomic.Xadd64(&h.counts[superBucket*timeHistNumSubBuckets+subBucket], 1)
-}
-
-const (
-	fInf    = 0x7FF0000000000000
-	fNegInf = 0xFFF0000000000000
-)
-
-func float64Inf() float64 {
-	inf := uint64(fInf)
-	return *(*float64)(unsafe.Pointer(&inf))
-}
-
-func float64NegInf() float64 {
-	inf := uint64(fNegInf)
-	return *(*float64)(unsafe.Pointer(&inf))
-}
-
-// timeHistogramMetricsBuckets generates a slice of boundaries for
-// the timeHistogram. These boundaries are represented in seconds,
-// not nanoseconds like the timeHistogram represents durations.
-func timeHistogramMetricsBuckets() []float64 {
-	b := make([]float64, timeHistTotalBuckets+1)
-	b[0] = float64NegInf()
-	// Super-bucket 0 has no bits above timeHistSubBucketBits
-	// set, so just iterate over each bucket and assign the
-	// incrementing bucket.
-	for i := 0; i < timeHistNumSubBuckets; i++ {
-		bucketNanos := uint64(i)
-		b[i+1] = float64(bucketNanos) / 1e9
-	}
-	// Generate the rest of the super-buckets. It's easier to reason
-	// about if we cut out the 0'th bucket, so subtract one since
-	// we just handled that bucket.
-	for i := 0; i < timeHistNumSuperBuckets-1; i++ {
-		for j := 0; j < timeHistNumSubBuckets; j++ {
-			// Set the super-bucket bit.
-			bucketNanos := uint64(1) << (i + timeHistSubBucketBits)
-			// Set the sub-bucket bits.
-			bucketNanos |= uint64(j) << i
-			// The index for this bucket is going to be the (i+1)'th super bucket
-			// (note that we're starting from zero, but handled the first super-bucket
-			// earlier, so we need to compensate), and the j'th sub bucket.
-			// Add 1 because we left space for -Inf.
-			bucketIndex := (i+1)*timeHistNumSubBuckets + j + 1
-			// Convert nanoseconds to seconds via a division.
-			// These values will all be exactly representable by a float64.
-			b[bucketIndex] = float64(bucketNanos) / 1e9
-		}
-	}
-	b[len(b)-1] = float64Inf()
-	return b
-}
diff --git a/contrib/go/_std_1.18/src/runtime/internal/atomic/atomic_amd64.go b/contrib/go/_std_1.18/src/runtime/internal/atomic/atomic_amd64.go
deleted file mode 100644
index e36eb83a11..0000000000
--- a/contrib/go/_std_1.18/src/runtime/internal/atomic/atomic_amd64.go
+++ /dev/null
@@ -1,116 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package atomic
-
-import "unsafe"
-
-// Export some functions via linkname to assembly in sync/atomic.
-//go:linkname Load
-//go:linkname Loadp
-//go:linkname Load64
-
-//go:nosplit
-//go:noinline
-func Load(ptr *uint32) uint32 {
-	return *ptr
-}
-
-//go:nosplit
-//go:noinline
-func Loadp(ptr unsafe.Pointer) unsafe.Pointer {
-	return *(*unsafe.Pointer)(ptr)
-}
-
-//go:nosplit
-//go:noinline
-func Load64(ptr *uint64) uint64 {
-	return *ptr
-}
-
-//go:nosplit
-//go:noinline
-func LoadAcq(ptr *uint32) uint32 {
-	return *ptr
-}
-
-//go:nosplit
-//go:noinline
-func LoadAcq64(ptr *uint64) uint64 {
-	return *ptr
-}
-
-//go:nosplit
-//go:noinline
-func LoadAcquintptr(ptr *uintptr) uintptr {
-	return *ptr
-}
-
-//go:noescape
-func Xadd(ptr *uint32, delta int32) uint32
-
-//go:noescape
-func Xadd64(ptr *uint64, delta int64) uint64
-
-//go:noescape
-func Xadduintptr(ptr *uintptr, delta uintptr) uintptr
-
-//go:noescape
-func Xchg(ptr *uint32, new uint32) uint32
-
-//go:noescape
-func Xchg64(ptr *uint64, new uint64) uint64
-
-//go:noescape
-func Xchguintptr(ptr *uintptr, new uintptr) uintptr
-
-//go:nosplit
-//go:noinline
-func Load8(ptr *uint8) uint8 {
-	return *ptr
-}
-
-//go:noescape
-func And8(ptr *uint8, val uint8)
-
-//go:noescape
-func Or8(ptr *uint8, val uint8)
-
-//go:noescape
-func And(ptr *uint32, val uint32)
-
-//go:noescape
-func Or(ptr *uint32, val uint32)
-
-// NOTE: Do not add atomicxor8 (XOR is not idempotent).
-
-//go:noescape
-func Cas64(ptr *uint64, old, new uint64) bool
-
-//go:noescape
-func CasRel(ptr *uint32, old, new uint32) bool
-
-//go:noescape
-func Store(ptr *uint32, val uint32)
-
-//go:noescape
-func Store8(ptr *uint8, val uint8)
-
-//go:noescape
-func Store64(ptr *uint64, val uint64)
-
-//go:noescape
-func StoreRel(ptr *uint32, val uint32)
-
-//go:noescape
-func StoreRel64(ptr *uint64, val uint64)
-
-//go:noescape
-func StoreReluintptr(ptr *uintptr, val uintptr)
-
-// StorepNoWB performs *ptr = val atomically and without a write
-// barrier.
-//
-// NO go:noescape annotation; see atomic_pointer.go.
-func StorepNoWB(ptr unsafe.Pointer, val unsafe.Pointer)
diff --git a/contrib/go/_std_1.18/src/runtime/internal/atomic/types.go b/contrib/go/_std_1.18/src/runtime/internal/atomic/types.go
deleted file mode 100644
index 1a240d7c91..0000000000
--- a/contrib/go/_std_1.18/src/runtime/internal/atomic/types.go
+++ /dev/null
@@ -1,395 +0,0 @@
-// Copyright 2021 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package atomic
-
-import "unsafe"
-
-// Int32 is an atomically accessed int32 value.
-//
-// An Int32 must not be copied.
-type Int32 struct {
-	noCopy noCopy
-	value  int32
-}
-
-// Load accesses and returns the value atomically.
-func (i *Int32) Load() int32 {
-	return Loadint32(&i.value)
-}
-
-// Store updates the value atomically.
-func (i *Int32) Store(value int32) {
-	Storeint32(&i.value, value)
-}
-
-// CompareAndSwap atomically compares i's value with old,
-// and if they're equal, swaps i's value with new.
-//
-// Returns true if the operation succeeded.
-func (i *Int32) CompareAndSwap(old, new int32) bool {
-	return Casint32(&i.value, old, new)
-}
-
-// Swap replaces i's value with new, returning
-// i's value before the replacement.
-func (i *Int32) Swap(new int32) int32 {
-	return Xchgint32(&i.value, new)
-}
-
-// Add adds delta to i atomically, returning
-// the new updated value.
-//
-// This operation wraps around in the usual
-// two's-complement way.
-func (i *Int32) Add(delta int32) int32 {
-	return Xaddint32(&i.value, delta)
-}
-
-// Int64 is an atomically accessed int64 value.
-//
-// An Int64 must not be copied.
-type Int64 struct {
-	noCopy noCopy
-	value  int64
-}
-
-// Load accesses and returns the value atomically.
-func (i *Int64) Load() int64 {
-	return Loadint64(&i.value)
-}
-
-// Store updates the value atomically.
-func (i *Int64) Store(value int64) {
-	Storeint64(&i.value, value)
-}
-
-// CompareAndSwap atomically compares i's value with old,
-// and if they're equal, swaps i's value with new.
-//
-// Returns true if the operation succeeded.
-func (i *Int64) CompareAndSwap(old, new int64) bool {
-	return Casint64(&i.value, old, new)
-}
-
-// Swap replaces i's value with new, returning
-// i's value before the replacement.
-func (i *Int64) Swap(new int64) int64 {
-	return Xchgint64(&i.value, new)
-}
-
-// Add adds delta to i atomically, returning
-// the new updated value.
-//
-// This operation wraps around in the usual
-// two's-complement way.
-func (i *Int64) Add(delta int64) int64 {
-	return Xaddint64(&i.value, delta)
-}
-
-// Uint8 is an atomically accessed uint8 value.
-//
-// A Uint8 must not be copied.
-type Uint8 struct {
-	noCopy noCopy
-	value  uint8
-}
-
-// Load accesses and returns the value atomically.
-func (u *Uint8) Load() uint8 {
-	return Load8(&u.value)
-}
-
-// Store updates the value atomically.
-func (u *Uint8) Store(value uint8) {
-	Store8(&u.value, value)
-}
-
-// And takes value and performs a bit-wise
-// "and" operation with the value of u, storing
-// the result into u.
-//
-// The full process is performed atomically.
-func (u *Uint8) And(value uint8) {
-	And8(&u.value, value)
-}
-
-// Or takes value and performs a bit-wise
-// "or" operation with the value of u, storing
-// the result into u.
-//
-// The full process is performed atomically.
-func (u *Uint8) Or(value uint8) {
-	Or8(&u.value, value)
-}
-
-// Uint32 is an atomically accessed uint32 value.
-//
-// A Uint32 must not be copied.
-type Uint32 struct {
-	noCopy noCopy
-	value  uint32
-}
-
-// Load accesses and returns the value atomically.
-func (u *Uint32) Load() uint32 {
-	return Load(&u.value)
-}
-
-// LoadAcquire is a partially unsynchronized version
-// of Load that relaxes ordering constraints. Other threads
-// may observe operations that precede this operation to
-// occur after it, but no operation that occurs after it
-// on this thread can be observed to occur before it.
-//
-// WARNING: Use sparingly and with great care.
-func (u *Uint32) LoadAcquire() uint32 {
-	return LoadAcq(&u.value)
-}
-
-// Store updates the value atomically.
-func (u *Uint32) Store(value uint32) {
-	Store(&u.value, value)
-}
-
-// StoreRelease is a partially unsynchronized version
-// of Store that relaxes ordering constraints. Other threads
-// may observe operations that occur after this operation to
-// precede it, but no operation that precedes it
-// on this thread can be observed to occur after it.
-//
-// WARNING: Use sparingly and with great care.
-func (u *Uint32) StoreRelease(value uint32) {
-	StoreRel(&u.value, value)
-}
-
-// CompareAndSwap atomically compares u's value with old,
-// and if they're equal, swaps u's value with new.
-//
-// Returns true if the operation succeeded.
-func (u *Uint32) CompareAndSwap(old, new uint32) bool {
-	return Cas(&u.value, old, new)
-}
-
-// CompareAndSwapRelease is a partially unsynchronized version
-// of Cas that relaxes ordering constraints. Other threads
-// may observe operations that occur after this operation to
-// precede it, but no operation that precedes it
-// on this thread can be observed to occur after it.
-//
-// Returns true if the operation succeeded.
-//
-// WARNING: Use sparingly and with great care.
-func (u *Uint32) CompareAndSwapRelease(old, new uint32) bool {
-	return CasRel(&u.value, old, new)
-}
-
-// Swap replaces u's value with new, returning
-// u's value before the replacement.
-func (u *Uint32) Swap(value uint32) uint32 {
-	return Xchg(&u.value, value)
-}
-
-// And takes value and performs a bit-wise
-// "and" operation with the value of u, storing
-// the result into u.
-//
-// The full process is performed atomically.
-func (u *Uint32) And(value uint32) {
-	And(&u.value, value)
-}
-
-// Or takes value and performs a bit-wise
-// "or" operation with the value of u, storing
-// the result into u.
-//
-// The full process is performed atomically.
-func (u *Uint32) Or(value uint32) {
-	Or(&u.value, value)
-}
-
-// Add adds delta to u atomically, returning
-// the new updated value.
-//
-// This operation wraps around in the usual
-// two's-complement way.
-func (u *Uint32) Add(delta int32) uint32 {
-	return Xadd(&u.value, delta)
-}
-
-// Uint64 is an atomically accessed uint64 value.
-//
-// A Uint64 must not be copied.
-type Uint64 struct {
-	noCopy noCopy
-	value  uint64
-}
-
-// Load accesses and returns the value atomically.
-func (u *Uint64) Load() uint64 {
-	return Load64(&u.value)
-}
-
-// Store updates the value atomically.
-func (u *Uint64) Store(value uint64) {
-	Store64(&u.value, value)
-}
-
-// CompareAndSwap atomically compares u's value with old,
-// and if they're equal, swaps u's value with new.
-//
-// Returns true if the operation succeeded.
-func (u *Uint64) CompareAndSwap(old, new uint64) bool {
-	return Cas64(&u.value, old, new)
-}
-
-// Swap replaces u's value with new, returning
-// u's value before the replacement.
-func (u *Uint64) Swap(value uint64) uint64 {
-	return Xchg64(&u.value, value)
-}
-
-// Add adds delta to u atomically, returning
-// the new updated value.
-//
-// This operation wraps around in the usual
-// two's-complement way.
-func (u *Uint64) Add(delta int64) uint64 {
-	return Xadd64(&u.value, delta)
-}
-
-// Uintptr is an atomically accessed uintptr value.
-//
-// A Uintptr must not be copied.
-type Uintptr struct {
-	noCopy noCopy
-	value  uintptr
-}
-
-// Load accesses and returns the value atomically.
-func (u *Uintptr) Load() uintptr {
-	return Loaduintptr(&u.value)
-}
-
-// LoadAcquire is a partially unsynchronized version
-// of Load that relaxes ordering constraints. Other threads
-// may observe operations that precede this operation to
-// occur after it, but no operation that occurs after it
-// on this thread can be observed to occur before it.
-//
-// WARNING: Use sparingly and with great care.
-func (u *Uintptr) LoadAcquire() uintptr {
-	return LoadAcquintptr(&u.value)
-}
-
-// Store updates the value atomically.
-func (u *Uintptr) Store(value uintptr) {
-	Storeuintptr(&u.value, value)
-}
-
-// StoreRelease is a partially unsynchronized version
-// of Store that relaxes ordering constraints. Other threads
-// may observe operations that occur after this operation to
-// precede it, but no operation that precedes it
-// on this thread can be observed to occur after it.
-//
-// WARNING: Use sparingly and with great care.
-func (u *Uintptr) StoreRelease(value uintptr) {
-	StoreReluintptr(&u.value, value)
-}
-
-// CompareAndSwap atomically compares u's value with old,
-// and if they're equal, swaps u's value with new.
-//
-// Returns true if the operation succeeded.
-func (u *Uintptr) CompareAndSwap(old, new uintptr) bool {
-	return Casuintptr(&u.value, old, new)
-}
-
-// Swap replaces u's value with new, returning
-// u's value before the replacement.
-func (u *Uintptr) Swap(value uintptr) uintptr {
-	return Xchguintptr(&u.value, value)
-}
-
-// Add adds delta to u atomically, returning
-// the new updated value.
-//
-// This operation wraps around in the usual
-// two's-complement way.
-func (u *Uintptr) Add(delta uintptr) uintptr {
-	return Xadduintptr(&u.value, delta)
-}
-
-// Float64 is an atomically accessed float64 value.
-//
-// A Float64 must not be copied.
-type Float64 struct {
-	u Uint64
-}
-
-// Load accesses and returns the value atomically.
-func (f *Float64) Load() float64 {
-	r := f.u.Load()
-	return *(*float64)(unsafe.Pointer(&r))
-}
-
-// Store updates the value atomically.
-func (f *Float64) Store(value float64) {
-	f.u.Store(*(*uint64)(unsafe.Pointer(&value)))
-}
-
-// UnsafePointer is an atomically accessed unsafe.Pointer value.
-//
-// Note that because of the atomicity guarantees, stores to values
-// of this type never trigger a write barrier, and the relevant
-// methods are suffixed with "NoWB" to indicate that explicitly.
-// As a result, this type should be used carefully, and sparingly,
-// mostly with values that do not live in the Go heap anyway.
-//
-// An UnsafePointer must not be copied.
-type UnsafePointer struct {
-	noCopy noCopy
-	value  unsafe.Pointer
-}
-
-// Load accesses and returns the value atomically.
-func (u *UnsafePointer) Load() unsafe.Pointer {
-	return Loadp(unsafe.Pointer(&u.value))
-}
-
-// StoreNoWB updates the value atomically.
-//
-// WARNING: As the name implies this operation does *not*
-// perform a write barrier on value, and so this operation may
-// hide pointers from the GC. Use with care and sparingly.
-// It is safe to use with values not found in the Go heap.
-func (u *UnsafePointer) StoreNoWB(value unsafe.Pointer) {
-	StorepNoWB(unsafe.Pointer(&u.value), value)
-}
-
-// CompareAndSwapNoWB atomically (with respect to other methods)
-// compares u's value with old, and if they're equal,
-// swaps u's value with new.
-//
-// Returns true if the operation succeeded.
-//
-// WARNING: As the name implies this operation does *not*
-// perform a write barrier on value, and so this operation may
-// hide pointers from the GC. Use with care and sparingly.
-// It is safe to use with values not found in the Go heap.
-func (u *UnsafePointer) CompareAndSwapNoWB(old, new unsafe.Pointer) bool {
-	return Casp1(&u.value, old, new)
-}
-
-// noCopy may be embedded into structs which must not be copied
-// after the first use.
-//
-// See https://golang.org/issues/8005#issuecomment-190753527
-// for details.
-type noCopy struct{}
-
-// Lock is a no-op used by -copylocks checker from `go vet`.
-func (*noCopy) Lock()   {}
-func (*noCopy) Unlock() {}
diff --git a/contrib/go/_std_1.18/src/runtime/internal/syscall/asm_linux_amd64.s b/contrib/go/_std_1.18/src/runtime/internal/syscall/asm_linux_amd64.s
deleted file mode 100644
index 961d9bd640..0000000000
--- a/contrib/go/_std_1.18/src/runtime/internal/syscall/asm_linux_amd64.s
+++ /dev/null
@@ -1,33 +0,0 @@
-// Copyright 2022 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-#include "textflag.h"
-
-// func Syscall6(num, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, errno uintptr)
-//
-// Syscall # in AX, args in DI SI DX R10 R8 R9, return in AX DX.
-//
-// Note that this differs from "standard" ABI convention, which would pass 4th
-// arg in CX, not R10.
-TEXT ·Syscall6(SB),NOSPLIT,$0-80
-	MOVQ	num+0(FP), AX	// syscall entry
-	MOVQ	a1+8(FP), DI
-	MOVQ	a2+16(FP), SI
-	MOVQ	a3+24(FP), DX
-	MOVQ	a4+32(FP), R10
-	MOVQ	a5+40(FP), R8
-	MOVQ	a6+48(FP), R9
-	SYSCALL
-	CMPQ	AX, $0xfffffffffffff001
-	JLS	ok
-	MOVQ	$-1, r1+56(FP)
-	MOVQ	$0, r2+64(FP)
-	NEGQ	AX
-	MOVQ	AX, errno+72(FP)
-	RET
-ok:
-	MOVQ	AX, r1+56(FP)
-	MOVQ	DX, r2+64(FP)
-	MOVQ	$0, errno+72(FP)
-	RET
diff --git a/contrib/go/_std_1.18/src/runtime/internal/syscall/syscall_linux.go b/contrib/go/_std_1.18/src/runtime/internal/syscall/syscall_linux.go
deleted file mode 100644
index 06d5f21e7c..0000000000
--- a/contrib/go/_std_1.18/src/runtime/internal/syscall/syscall_linux.go
+++ /dev/null
@@ -1,12 +0,0 @@
-// Copyright 2022 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package syscall provides the syscall primitives required for the runtime.
-package syscall
-
-// TODO(https://go.dev/issue/51087): This package is incomplete and currently
-// only contains very minimal support for Linux.
-
-// Syscall6 calls system call number 'num' with arguments a1-6.
-func Syscall6(num, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, errno uintptr)
diff --git a/contrib/go/_std_1.18/src/runtime/lfstack_64bit.go b/contrib/go/_std_1.18/src/runtime/lfstack_64bit.go
deleted file mode 100644
index 3f0e480897..0000000000
--- a/contrib/go/_std_1.18/src/runtime/lfstack_64bit.go
+++ /dev/null
@@ -1,58 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build amd64 || arm64 || mips64 || mips64le || ppc64 || ppc64le || riscv64 || s390x || wasm
-
-package runtime
-
-import "unsafe"
-
-const (
-	// addrBits is the number of bits needed to represent a virtual address.
-	//
-	// See heapAddrBits for a table of address space sizes on
-	// various architectures. 48 bits is enough for all
-	// architectures except s390x.
-	//
-	// On AMD64, virtual addresses are 48-bit (or 57-bit) numbers sign extended to 64.
-	// We shift the address left 16 to eliminate the sign extended part and make
-	// room in the bottom for the count.
-	//
-	// On s390x, virtual addresses are 64-bit. There's not much we
-	// can do about this, so we just hope that the kernel doesn't
-	// get to really high addresses and panic if it does.
-	addrBits = 48
-
-	// In addition to the 16 bits taken from the top, we can take 3 from the
-	// bottom, because node must be pointer-aligned, giving a total of 19 bits
-	// of count.
-	cntBits = 64 - addrBits + 3
-
-	// On AIX, 64-bit addresses are split into 36-bit segment number and 28-bit
-	// offset in segment.  Segment numbers in the range 0x0A0000000-0x0AFFFFFFF(LSA)
-	// are available for mmap.
-	// We assume all lfnode addresses are from memory allocated with mmap.
-	// We use one bit to distinguish between the two ranges.
-	aixAddrBits = 57
-	aixCntBits  = 64 - aixAddrBits + 3
-)
-
-func lfstackPack(node *lfnode, cnt uintptr) uint64 {
-	if GOARCH == "ppc64" && GOOS == "aix" {
-		return uint64(uintptr(unsafe.Pointer(node)))<<(64-aixAddrBits) | uint64(cnt&(1<<aixCntBits-1))
-	}
-	return uint64(uintptr(unsafe.Pointer(node)))<<(64-addrBits) | uint64(cnt&(1<<cntBits-1))
-}
-
-func lfstackUnpack(val uint64) *lfnode {
-	if GOARCH == "amd64" {
-		// amd64 systems can place the stack above the VA hole, so we need to sign extend
-		// val before unpacking.
-		return (*lfnode)(unsafe.Pointer(uintptr(int64(val) >> cntBits << 3)))
-	}
-	if GOARCH == "ppc64" && GOOS == "aix" {
-		return (*lfnode)(unsafe.Pointer(uintptr((val >> aixCntBits << 3) | 0xa<<56)))
-	}
-	return (*lfnode)(unsafe.Pointer(uintptr(val >> cntBits << 3)))
-}
diff --git a/contrib/go/_std_1.18/src/runtime/lock_futex.go b/contrib/go/_std_1.18/src/runtime/lock_futex.go
deleted file mode 100644
index 575df7a1d5..0000000000
--- a/contrib/go/_std_1.18/src/runtime/lock_futex.go
+++ /dev/null
@@ -1,245 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build dragonfly || freebsd || linux
-
-package runtime
-
-import (
-	"runtime/internal/atomic"
-	"unsafe"
-)
-
-// This implementation depends on OS-specific implementations of
-//
-//	futexsleep(addr *uint32, val uint32, ns int64)
-//		Atomically,
-//			if *addr == val { sleep }
-//		Might be woken up spuriously; that's allowed.
-//		Don't sleep longer than ns; ns < 0 means forever.
-//
-//	futexwakeup(addr *uint32, cnt uint32)
-//		If any procs are sleeping on addr, wake up at most cnt.
-
-const (
-	mutex_unlocked = 0
-	mutex_locked   = 1
-	mutex_sleeping = 2
-
-	active_spin     = 4
-	active_spin_cnt = 30
-	passive_spin    = 1
-)
-
-// Possible lock states are mutex_unlocked, mutex_locked and mutex_sleeping.
-// mutex_sleeping means that there is presumably at least one sleeping thread.
-// Note that there can be spinning threads during all states - they do not
-// affect mutex's state.
-
-// We use the uintptr mutex.key and note.key as a uint32.
-//go:nosplit
-func key32(p *uintptr) *uint32 {
-	return (*uint32)(unsafe.Pointer(p))
-}
-
-func lock(l *mutex) {
-	lockWithRank(l, getLockRank(l))
-}
-
-func lock2(l *mutex) {
-	gp := getg()
-
-	if gp.m.locks < 0 {
-		throw("runtime·lock: lock count")
-	}
-	gp.m.locks++
-
-	// Speculative grab for lock.
-	v := atomic.Xchg(key32(&l.key), mutex_locked)
-	if v == mutex_unlocked {
-		return
-	}
-
-	// wait is either MUTEX_LOCKED or MUTEX_SLEEPING
-	// depending on whether there is a thread sleeping
-	// on this mutex. If we ever change l->key from
-	// MUTEX_SLEEPING to some other value, we must be
-	// careful to change it back to MUTEX_SLEEPING before
-	// returning, to ensure that the sleeping thread gets
-	// its wakeup call.
-	wait := v
-
-	// On uniprocessors, no point spinning.
-	// On multiprocessors, spin for ACTIVE_SPIN attempts.
-	spin := 0
-	if ncpu > 1 {
-		spin = active_spin
-	}
-	for {
-		// Try for lock, spinning.
-		for i := 0; i < spin; i++ {
-			for l.key == mutex_unlocked {
-				if atomic.Cas(key32(&l.key), mutex_unlocked, wait) {
-					return
-				}
-			}
-			procyield(active_spin_cnt)
-		}
-
-		// Try for lock, rescheduling.
-		for i := 0; i < passive_spin; i++ {
-			for l.key == mutex_unlocked {
-				if atomic.Cas(key32(&l.key), mutex_unlocked, wait) {
-					return
-				}
-			}
-			osyield()
-		}
-
-		// Sleep.
-		v = atomic.Xchg(key32(&l.key), mutex_sleeping)
-		if v == mutex_unlocked {
-			return
-		}
-		wait = mutex_sleeping
-		futexsleep(key32(&l.key), mutex_sleeping, -1)
-	}
-}
-
-func unlock(l *mutex) {
-	unlockWithRank(l)
-}
-
-func unlock2(l *mutex) {
-	v := atomic.Xchg(key32(&l.key), mutex_unlocked)
-	if v == mutex_unlocked {
-		throw("unlock of unlocked lock")
-	}
-	if v == mutex_sleeping {
-		futexwakeup(key32(&l.key), 1)
-	}
-
-	gp := getg()
-	gp.m.locks--
-	if gp.m.locks < 0 {
-		throw("runtime·unlock: lock count")
-	}
-	if gp.m.locks == 0 && gp.preempt { // restore the preemption request in case we've cleared it in newstack
-		gp.stackguard0 = stackPreempt
-	}
-}
-
-// One-time notifications.
-func noteclear(n *note) {
-	n.key = 0
-}
-
-func notewakeup(n *note) {
-	old := atomic.Xchg(key32(&n.key), 1)
-	if old != 0 {
-		print("notewakeup - double wakeup (", old, ")\n")
-		throw("notewakeup - double wakeup")
-	}
-	futexwakeup(key32(&n.key), 1)
-}
-
-func notesleep(n *note) {
-	gp := getg()
-	if gp != gp.m.g0 {
-		throw("notesleep not on g0")
-	}
-	ns := int64(-1)
-	if *cgo_yield != nil {
-		// Sleep for an arbitrary-but-moderate interval to poll libc interceptors.
-		ns = 10e6
-	}
-	for atomic.Load(key32(&n.key)) == 0 {
-		gp.m.blocked = true
-		futexsleep(key32(&n.key), 0, ns)
-		if *cgo_yield != nil {
-			asmcgocall(*cgo_yield, nil)
-		}
-		gp.m.blocked = false
-	}
-}
-
-// May run with m.p==nil if called from notetsleep, so write barriers
-// are not allowed.
-//
-//go:nosplit
-//go:nowritebarrier
-func notetsleep_internal(n *note, ns int64) bool {
-	gp := getg()
-
-	if ns < 0 {
-		if *cgo_yield != nil {
-			// Sleep for an arbitrary-but-moderate interval to poll libc interceptors.
-			ns = 10e6
-		}
-		for atomic.Load(key32(&n.key)) == 0 {
-			gp.m.blocked = true
-			futexsleep(key32(&n.key), 0, ns)
-			if *cgo_yield != nil {
-				asmcgocall(*cgo_yield, nil)
-			}
-			gp.m.blocked = false
-		}
-		return true
-	}
-
-	if atomic.Load(key32(&n.key)) != 0 {
-		return true
-	}
-
-	deadline := nanotime() + ns
-	for {
-		if *cgo_yield != nil && ns > 10e6 {
-			ns = 10e6
-		}
-		gp.m.blocked = true
-		futexsleep(key32(&n.key), 0, ns)
-		if *cgo_yield != nil {
-			asmcgocall(*cgo_yield, nil)
-		}
-		gp.m.blocked = false
-		if atomic.Load(key32(&n.key)) != 0 {
-			break
-		}
-		now := nanotime()
-		if now >= deadline {
-			break
-		}
-		ns = deadline - now
-	}
-	return atomic.Load(key32(&n.key)) != 0
-}
-
-func notetsleep(n *note, ns int64) bool {
-	gp := getg()
-	if gp != gp.m.g0 && gp.m.preemptoff != "" {
-		throw("notetsleep not on g0")
-	}
-
-	return notetsleep_internal(n, ns)
-}
-
-// same as runtime·notetsleep, but called on user g (not g0)
-// calls only nosplit functions between entersyscallblock/exitsyscall
-func notetsleepg(n *note, ns int64) bool {
-	gp := getg()
-	if gp == gp.m.g0 {
-		throw("notetsleepg on g0")
-	}
-
-	entersyscallblock()
-	ok := notetsleep_internal(n, ns)
-	exitsyscall()
-	return ok
-}
-
-func beforeIdle(int64, int64) (*g, bool) {
-	return nil, false
-}
-
-func checkTimeouts() {}
diff --git a/contrib/go/_std_1.18/src/runtime/lock_sema.go b/contrib/go/_std_1.18/src/runtime/lock_sema.go
deleted file mode 100644
index db36df1f37..0000000000
--- a/contrib/go/_std_1.18/src/runtime/lock_sema.go
+++ /dev/null
@@ -1,304 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || netbsd || openbsd || plan9 || solaris || windows
-
-package runtime
-
-import (
-	"runtime/internal/atomic"
-	"unsafe"
-)
-
-// This implementation depends on OS-specific implementations of
-//
-//	func semacreate(mp *m)
-//		Create a semaphore for mp, if it does not already have one.
-//
-//	func semasleep(ns int64) int32
-//		If ns < 0, acquire m's semaphore and return 0.
-//		If ns >= 0, try to acquire m's semaphore for at most ns nanoseconds.
-//		Return 0 if the semaphore was acquired, -1 if interrupted or timed out.
-//
-//	func semawakeup(mp *m)
-//		Wake up mp, which is or will soon be sleeping on its semaphore.
-//
-const (
-	locked uintptr = 1
-
-	active_spin     = 4
-	active_spin_cnt = 30
-	passive_spin    = 1
-)
-
-func lock(l *mutex) {
-	lockWithRank(l, getLockRank(l))
-}
-
-func lock2(l *mutex) {
-	gp := getg()
-	if gp.m.locks < 0 {
-		throw("runtime·lock: lock count")
-	}
-	gp.m.locks++
-
-	// Speculative grab for lock.
-	if atomic.Casuintptr(&l.key, 0, locked) {
-		return
-	}
-	semacreate(gp.m)
-
-	// On uniprocessor's, no point spinning.
-	// On multiprocessors, spin for ACTIVE_SPIN attempts.
-	spin := 0
-	if ncpu > 1 {
-		spin = active_spin
-	}
-Loop:
-	for i := 0; ; i++ {
-		v := atomic.Loaduintptr(&l.key)
-		if v&locked == 0 {
-			// Unlocked. Try to lock.
-			if atomic.Casuintptr(&l.key, v, v|locked) {
-				return
-			}
-			i = 0
-		}
-		if i < spin {
-			procyield(active_spin_cnt)
-		} else if i < spin+passive_spin {
-			osyield()
-		} else {
-			// Someone else has it.
-			// l->waitm points to a linked list of M's waiting
-			// for this lock, chained through m->nextwaitm.
-			// Queue this M.
-			for {
-				gp.m.nextwaitm = muintptr(v &^ locked)
-				if atomic.Casuintptr(&l.key, v, uintptr(unsafe.Pointer(gp.m))|locked) {
-					break
-				}
-				v = atomic.Loaduintptr(&l.key)
-				if v&locked == 0 {
-					continue Loop
-				}
-			}
-			if v&locked != 0 {
-				// Queued. Wait.
-				semasleep(-1)
-				i = 0
-			}
-		}
-	}
-}
-
-func unlock(l *mutex) {
-	unlockWithRank(l)
-}
-
-//go:nowritebarrier
-// We might not be holding a p in this code.
-func unlock2(l *mutex) {
-	gp := getg()
-	var mp *m
-	for {
-		v := atomic.Loaduintptr(&l.key)
-		if v == locked {
-			if atomic.Casuintptr(&l.key, locked, 0) {
-				break
-			}
-		} else {
-			// Other M's are waiting for the lock.
-			// Dequeue an M.
-			mp = muintptr(v &^ locked).ptr()
-			if atomic.Casuintptr(&l.key, v, uintptr(mp.nextwaitm)) {
-				// Dequeued an M.  Wake it.
-				semawakeup(mp)
-				break
-			}
-		}
-	}
-	gp.m.locks--
-	if gp.m.locks < 0 {
-		throw("runtime·unlock: lock count")
-	}
-	if gp.m.locks == 0 && gp.preempt { // restore the preemption request in case we've cleared it in newstack
-		gp.stackguard0 = stackPreempt
-	}
-}
-
-// One-time notifications.
-func noteclear(n *note) {
-	if GOOS == "aix" {
-		// On AIX, semaphores might not synchronize the memory in some
-		// rare cases. See issue #30189.
-		atomic.Storeuintptr(&n.key, 0)
-	} else {
-		n.key = 0
-	}
-}
-
-func notewakeup(n *note) {
-	var v uintptr
-	for {
-		v = atomic.Loaduintptr(&n.key)
-		if atomic.Casuintptr(&n.key, v, locked) {
-			break
-		}
-	}
-
-	// Successfully set waitm to locked.
-	// What was it before?
-	switch {
-	case v == 0:
-		// Nothing was waiting. Done.
-	case v == locked:
-		// Two notewakeups! Not allowed.
-		throw("notewakeup - double wakeup")
-	default:
-		// Must be the waiting m. Wake it up.
-		semawakeup((*m)(unsafe.Pointer(v)))
-	}
-}
-
-func notesleep(n *note) {
-	gp := getg()
-	if gp != gp.m.g0 {
-		throw("notesleep not on g0")
-	}
-	semacreate(gp.m)
-	if !atomic.Casuintptr(&n.key, 0, uintptr(unsafe.Pointer(gp.m))) {
-		// Must be locked (got wakeup).
-		if n.key != locked {
-			throw("notesleep - waitm out of sync")
-		}
-		return
-	}
-	// Queued. Sleep.
-	gp.m.blocked = true
-	if *cgo_yield == nil {
-		semasleep(-1)
-	} else {
-		// Sleep for an arbitrary-but-moderate interval to poll libc interceptors.
-		const ns = 10e6
-		for atomic.Loaduintptr(&n.key) == 0 {
-			semasleep(ns)
-			asmcgocall(*cgo_yield, nil)
-		}
-	}
-	gp.m.blocked = false
-}
-
-//go:nosplit
-func notetsleep_internal(n *note, ns int64, gp *g, deadline int64) bool {
-	// gp and deadline are logically local variables, but they are written
-	// as parameters so that the stack space they require is charged
-	// to the caller.
-	// This reduces the nosplit footprint of notetsleep_internal.
-	gp = getg()
-
-	// Register for wakeup on n->waitm.
-	if !atomic.Casuintptr(&n.key, 0, uintptr(unsafe.Pointer(gp.m))) {
-		// Must be locked (got wakeup).
-		if n.key != locked {
-			throw("notetsleep - waitm out of sync")
-		}
-		return true
-	}
-	if ns < 0 {
-		// Queued. Sleep.
-		gp.m.blocked = true
-		if *cgo_yield == nil {
-			semasleep(-1)
-		} else {
-			// Sleep in arbitrary-but-moderate intervals to poll libc interceptors.
-			const ns = 10e6
-			for semasleep(ns) < 0 {
-				asmcgocall(*cgo_yield, nil)
-			}
-		}
-		gp.m.blocked = false
-		return true
-	}
-
-	deadline = nanotime() + ns
-	for {
-		// Registered. Sleep.
-		gp.m.blocked = true
-		if *cgo_yield != nil && ns > 10e6 {
-			ns = 10e6
-		}
-		if semasleep(ns) >= 0 {
-			gp.m.blocked = false
-			// Acquired semaphore, semawakeup unregistered us.
-			// Done.
-			return true
-		}
-		if *cgo_yield != nil {
-			asmcgocall(*cgo_yield, nil)
-		}
-		gp.m.blocked = false
-		// Interrupted or timed out. Still registered. Semaphore not acquired.
-		ns = deadline - nanotime()
-		if ns <= 0 {
-			break
-		}
-		// Deadline hasn't arrived. Keep sleeping.
-	}
-
-	// Deadline arrived. Still registered. Semaphore not acquired.
-	// Want to give up and return, but have to unregister first,
-	// so that any notewakeup racing with the return does not
-	// try to grant us the semaphore when we don't expect it.
-	for {
-		v := atomic.Loaduintptr(&n.key)
-		switch v {
-		case uintptr(unsafe.Pointer(gp.m)):
-			// No wakeup yet; unregister if possible.
-			if atomic.Casuintptr(&n.key, v, 0) {
-				return false
-			}
-		case locked:
-			// Wakeup happened so semaphore is available.
-			// Grab it to avoid getting out of sync.
-			gp.m.blocked = true
-			if semasleep(-1) < 0 {
-				throw("runtime: unable to acquire - semaphore out of sync")
-			}
-			gp.m.blocked = false
-			return true
-		default:
-			throw("runtime: unexpected waitm - semaphore out of sync")
-		}
-	}
-}
-
-func notetsleep(n *note, ns int64) bool {
-	gp := getg()
-	if gp != gp.m.g0 {
-		throw("notetsleep not on g0")
-	}
-	semacreate(gp.m)
-	return notetsleep_internal(n, ns, nil, 0)
-}
-
-// same as runtime·notetsleep, but called on user g (not g0)
-// calls only nosplit functions between entersyscallblock/exitsyscall
-func notetsleepg(n *note, ns int64) bool {
-	gp := getg()
-	if gp == gp.m.g0 {
-		throw("notetsleepg on g0")
-	}
-	semacreate(gp.m)
-	entersyscallblock()
-	ok := notetsleep_internal(n, ns, nil, 0)
-	exitsyscall()
-	return ok
-}
-
-func beforeIdle(int64, int64) (*g, bool) {
-	return nil, false
-}
-
-func checkTimeouts() {}
diff --git a/contrib/go/_std_1.18/src/runtime/lockrank.go b/contrib/go/_std_1.18/src/runtime/lockrank.go
deleted file mode 100644
index 4a16bc0ddb..0000000000
--- a/contrib/go/_std_1.18/src/runtime/lockrank.go
+++ /dev/null
@@ -1,251 +0,0 @@
-// Copyright 2020 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file records the static ranks of the locks in the runtime. If a lock
-// is not given a rank, then it is assumed to be a leaf lock, which means no other
-// lock can be acquired while it is held. Therefore, leaf locks do not need to be
-// given an explicit rank. We list all of the architecture-independent leaf locks
-// for documentation purposes, but don't list any of the architecture-dependent
-// locks (which are all leaf locks). debugLock is ignored for ranking, since it is used
-// when printing out lock ranking errors.
-//
-// lockInit(l *mutex, rank int) is used to set the rank of lock before it is used.
-// If there is no clear place to initialize a lock, then the rank of a lock can be
-// specified during the lock call itself via lockWithrank(l *mutex, rank int).
-//
-// Besides the static lock ranking (which is a total ordering of the locks), we
-// also represent and enforce the actual partial order among the locks in the
-// arcs[] array below. That is, if it is possible that lock B can be acquired when
-// lock A is the previous acquired lock that is still held, then there should be
-// an entry for A in arcs[B][]. We will currently fail not only if the total order
-// (the lock ranking) is violated, but also if there is a missing entry in the
-// partial order.
-
-package runtime
-
-type lockRank int
-
-// Constants representing the lock rank of the architecture-independent locks in
-// the runtime. Locks with lower rank must be taken before locks with higher
-// rank.
-const (
-	lockRankDummy lockRank = iota
-
-	// Locks held above sched
-	lockRankSysmon
-	lockRankScavenge
-	lockRankForcegc
-	lockRankSweepWaiters
-	lockRankAssistQueue
-	lockRankCpuprof
-	lockRankSweep
-
-	lockRankPollDesc
-	lockRankSched
-	lockRankDeadlock
-	lockRankAllg
-	lockRankAllp
-
-	lockRankTimers // Multiple timers locked simultaneously in destroy()
-	lockRankItab
-	lockRankReflectOffs
-	lockRankHchan // Multiple hchans acquired in lock order in syncadjustsudogs()
-	lockRankTraceBuf
-	lockRankFin
-	lockRankNotifyList
-	lockRankTraceStrings
-	lockRankMspanSpecial
-	lockRankProf
-	lockRankGcBitsArenas
-	lockRankRoot
-	lockRankTrace
-	lockRankTraceStackTab
-	lockRankNetpollInit
-
-	lockRankRwmutexW
-	lockRankRwmutexR
-
-	lockRankSpanSetSpine
-	lockRankGscan
-	lockRankStackpool
-	lockRankStackLarge
-	lockRankDefer
-	lockRankSudog
-
-	// Memory-related non-leaf locks
-	lockRankWbufSpans
-	lockRankMheap
-	lockRankMheapSpecial
-
-	// Memory-related leaf locks
-	lockRankGlobalAlloc
-	lockRankPageAllocScav
-
-	// Other leaf locks
-	lockRankGFree
-	// Generally, hchan must be acquired before gscan. But in one specific
-	// case (in syncadjustsudogs from markroot after the g has been suspended
-	// by suspendG), we allow gscan to be acquired, and then an hchan lock. To
-	// allow this case, we get this lockRankHchanLeaf rank in
-	// syncadjustsudogs(), rather than lockRankHchan. By using this special
-	// rank, we don't allow any further locks to be acquired other than more
-	// hchan locks.
-	lockRankHchanLeaf
-	lockRankPanic
-
-	// Leaf locks with no dependencies, so these constants are not actually used anywhere.
-	// There are other architecture-dependent leaf locks as well.
-	lockRankNewmHandoff
-	lockRankDebugPtrmask
-	lockRankFaketimeState
-	lockRankTicks
-	lockRankRaceFini
-	lockRankPollCache
-	lockRankDebug
-)
-
-// lockRankLeafRank is the rank of lock that does not have a declared rank, and hence is
-// a leaf lock.
-const lockRankLeafRank lockRank = 1000
-
-// lockNames gives the names associated with each of the above ranks
-var lockNames = []string{
-	lockRankDummy: "",
-
-	lockRankSysmon:       "sysmon",
-	lockRankScavenge:     "scavenge",
-	lockRankForcegc:      "forcegc",
-	lockRankSweepWaiters: "sweepWaiters",
-	lockRankAssistQueue:  "assistQueue",
-	lockRankCpuprof:      "cpuprof",
-	lockRankSweep:        "sweep",
-
-	lockRankPollDesc: "pollDesc",
-	lockRankSched:    "sched",
-	lockRankDeadlock: "deadlock",
-	lockRankAllg:     "allg",
-	lockRankAllp:     "allp",
-
-	lockRankTimers:      "timers",
-	lockRankItab:        "itab",
-	lockRankReflectOffs: "reflectOffs",
-
-	lockRankHchan:         "hchan",
-	lockRankTraceBuf:      "traceBuf",
-	lockRankFin:           "fin",
-	lockRankNotifyList:    "notifyList",
-	lockRankTraceStrings:  "traceStrings",
-	lockRankMspanSpecial:  "mspanSpecial",
-	lockRankProf:          "prof",
-	lockRankGcBitsArenas:  "gcBitsArenas",
-	lockRankRoot:          "root",
-	lockRankTrace:         "trace",
-	lockRankTraceStackTab: "traceStackTab",
-	lockRankNetpollInit:   "netpollInit",
-
-	lockRankRwmutexW: "rwmutexW",
-	lockRankRwmutexR: "rwmutexR",
-
-	lockRankSpanSetSpine: "spanSetSpine",
-	lockRankGscan:        "gscan",
-	lockRankStackpool:    "stackpool",
-	lockRankStackLarge:   "stackLarge",
-	lockRankDefer:        "defer",
-	lockRankSudog:        "sudog",
-
-	lockRankWbufSpans:    "wbufSpans",
-	lockRankMheap:        "mheap",
-	lockRankMheapSpecial: "mheapSpecial",
-
-	lockRankGlobalAlloc:   "globalAlloc.mutex",
-	lockRankPageAllocScav: "pageAlloc.scav.lock",
-
-	lockRankGFree:     "gFree",
-	lockRankHchanLeaf: "hchanLeaf",
-	lockRankPanic:     "panic",
-
-	lockRankNewmHandoff:   "newmHandoff.lock",
-	lockRankDebugPtrmask:  "debugPtrmask.lock",
-	lockRankFaketimeState: "faketimeState.lock",
-	lockRankTicks:         "ticks.lock",
-	lockRankRaceFini:      "raceFiniLock",
-	lockRankPollCache:     "pollCache.lock",
-	lockRankDebug:         "debugLock",
-}
-
-func (rank lockRank) String() string {
-	if rank == 0 {
-		return "UNKNOWN"
-	}
-	if rank == lockRankLeafRank {
-		return "LEAF"
-	}
-	return lockNames[rank]
-}
-
-// lockPartialOrder is a partial order among the various lock types, listing the
-// immediate ordering that has actually been observed in the runtime. Each entry
-// (which corresponds to a particular lock rank) specifies the list of locks
-// that can already be held immediately "above" it.
-//
-// So, for example, the lockRankSched entry shows that all the locks preceding
-// it in rank can actually be held. The allp lock shows that only the sysmon or
-// sched lock can be held immediately above it when it is acquired.
-var lockPartialOrder [][]lockRank = [][]lockRank{
-	lockRankDummy:         {},
-	lockRankSysmon:        {},
-	lockRankScavenge:      {lockRankSysmon},
-	lockRankForcegc:       {lockRankSysmon},
-	lockRankSweepWaiters:  {},
-	lockRankAssistQueue:   {},
-	lockRankCpuprof:       {},
-	lockRankSweep:         {},
-	lockRankPollDesc:      {},
-	lockRankSched:         {lockRankSysmon, lockRankScavenge, lockRankForcegc, lockRankSweepWaiters, lockRankAssistQueue, lockRankCpuprof, lockRankSweep, lockRankPollDesc},
-	lockRankDeadlock:      {lockRankDeadlock},
-	lockRankAllg:          {lockRankSysmon, lockRankSched},
-	lockRankAllp:          {lockRankSysmon, lockRankSched},
-	lockRankTimers:        {lockRankSysmon, lockRankScavenge, lockRankPollDesc, lockRankSched, lockRankAllp, lockRankTimers},
-	lockRankItab:          {},
-	lockRankReflectOffs:   {lockRankItab},
-	lockRankHchan:         {lockRankScavenge, lockRankSweep, lockRankHchan},
-	lockRankTraceBuf:      {lockRankSysmon, lockRankScavenge},
-	lockRankFin:           {lockRankSysmon, lockRankScavenge, lockRankSched, lockRankAllg, lockRankTimers, lockRankReflectOffs, lockRankHchan, lockRankTraceBuf},
-	lockRankNotifyList:    {},
-	lockRankTraceStrings:  {lockRankTraceBuf},
-	lockRankMspanSpecial:  {lockRankSysmon, lockRankScavenge, lockRankAssistQueue, lockRankCpuprof, lockRankSweep, lockRankSched, lockRankAllg, lockRankAllp, lockRankTimers, lockRankItab, lockRankReflectOffs, lockRankHchan, lockRankTraceBuf, lockRankNotifyList, lockRankTraceStrings},
-	lockRankProf:          {lockRankSysmon, lockRankScavenge, lockRankAssistQueue, lockRankCpuprof, lockRankSweep, lockRankSched, lockRankAllg, lockRankAllp, lockRankTimers, lockRankItab, lockRankReflectOffs, lockRankHchan, lockRankTraceBuf, lockRankNotifyList, lockRankTraceStrings},
-	lockRankGcBitsArenas:  {lockRankSysmon, lockRankScavenge, lockRankAssistQueue, lockRankCpuprof, lockRankSched, lockRankAllg, lockRankTimers, lockRankItab, lockRankReflectOffs, lockRankHchan, lockRankTraceBuf, lockRankNotifyList, lockRankTraceStrings},
-	lockRankRoot:          {},
-	lockRankTrace:         {lockRankSysmon, lockRankScavenge, lockRankForcegc, lockRankAssistQueue, lockRankSweep, lockRankSched, lockRankHchan, lockRankTraceBuf, lockRankTraceStrings, lockRankRoot},
-	lockRankTraceStackTab: {lockRankScavenge, lockRankForcegc, lockRankSweepWaiters, lockRankAssistQueue, lockRankSweep, lockRankSched, lockRankAllg, lockRankTimers, lockRankHchan, lockRankTraceBuf, lockRankFin, lockRankNotifyList, lockRankTraceStrings, lockRankRoot, lockRankTrace},
-	lockRankNetpollInit:   {lockRankTimers},
-
-	lockRankRwmutexW: {},
-	lockRankRwmutexR: {lockRankSysmon, lockRankRwmutexW},
-
-	lockRankSpanSetSpine:  {lockRankSysmon, lockRankScavenge, lockRankForcegc, lockRankAssistQueue, lockRankCpuprof, lockRankSweep, lockRankPollDesc, lockRankSched, lockRankAllg, lockRankAllp, lockRankTimers, lockRankItab, lockRankReflectOffs, lockRankHchan, lockRankTraceBuf, lockRankNotifyList, lockRankTraceStrings},
-	lockRankGscan:         {lockRankSysmon, lockRankScavenge, lockRankForcegc, lockRankSweepWaiters, lockRankAssistQueue, lockRankCpuprof, lockRankSweep, lockRankPollDesc, lockRankSched, lockRankTimers, lockRankItab, lockRankReflectOffs, lockRankHchan, lockRankTraceBuf, lockRankFin, lockRankNotifyList, lockRankTraceStrings, lockRankProf, lockRankGcBitsArenas, lockRankRoot, lockRankTrace, lockRankTraceStackTab, lockRankNetpollInit, lockRankSpanSetSpine},
-	lockRankStackpool:     {lockRankSysmon, lockRankScavenge, lockRankSweepWaiters, lockRankAssistQueue, lockRankCpuprof, lockRankSweep, lockRankPollDesc, lockRankSched, lockRankTimers, lockRankItab, lockRankReflectOffs, lockRankHchan, lockRankTraceBuf, lockRankFin, lockRankNotifyList, lockRankTraceStrings, lockRankProf, lockRankGcBitsArenas, lockRankRoot, lockRankTrace, lockRankTraceStackTab, lockRankNetpollInit, lockRankRwmutexR, lockRankSpanSetSpine, lockRankGscan},
-	lockRankStackLarge:    {lockRankSysmon, lockRankAssistQueue, lockRankSched, lockRankItab, lockRankHchan, lockRankProf, lockRankGcBitsArenas, lockRankRoot, lockRankSpanSetSpine, lockRankGscan},
-	lockRankDefer:         {},
-	lockRankSudog:         {lockRankHchan, lockRankNotifyList},
-	lockRankWbufSpans:     {lockRankSysmon, lockRankScavenge, lockRankSweepWaiters, lockRankAssistQueue, lockRankSweep, lockRankPollDesc, lockRankSched, lockRankAllg, lockRankTimers, lockRankItab, lockRankReflectOffs, lockRankHchan, lockRankFin, lockRankNotifyList, lockRankTraceStrings, lockRankMspanSpecial, lockRankProf, lockRankRoot, lockRankGscan, lockRankDefer, lockRankSudog},
-	lockRankMheap:         {lockRankSysmon, lockRankScavenge, lockRankSweepWaiters, lockRankAssistQueue, lockRankCpuprof, lockRankSweep, lockRankPollDesc, lockRankSched, lockRankAllg, lockRankAllp, lockRankTimers, lockRankItab, lockRankReflectOffs, lockRankHchan, lockRankTraceBuf, lockRankFin, lockRankNotifyList, lockRankTraceStrings, lockRankMspanSpecial, lockRankProf, lockRankGcBitsArenas, lockRankRoot, lockRankSpanSetSpine, lockRankGscan, lockRankStackpool, lockRankStackLarge, lockRankDefer, lockRankSudog, lockRankWbufSpans},
-	lockRankMheapSpecial:  {lockRankSysmon, lockRankScavenge, lockRankAssistQueue, lockRankCpuprof, lockRankSweep, lockRankPollDesc, lockRankSched, lockRankAllg, lockRankAllp, lockRankTimers, lockRankItab, lockRankReflectOffs, lockRankHchan, lockRankTraceBuf, lockRankNotifyList, lockRankTraceStrings},
-	lockRankGlobalAlloc:   {lockRankProf, lockRankSpanSetSpine, lockRankMheap, lockRankMheapSpecial},
-	lockRankPageAllocScav: {lockRankMheap},
-
-	lockRankGFree:     {lockRankSched},
-	lockRankHchanLeaf: {lockRankGscan, lockRankHchanLeaf},
-	lockRankPanic:     {lockRankDeadlock}, // plus any other lock held on throw.
-
-	lockRankNewmHandoff:   {},
-	lockRankDebugPtrmask:  {},
-	lockRankFaketimeState: {},
-	lockRankTicks:         {},
-	lockRankRaceFini:      {},
-	lockRankPollCache:     {},
-	lockRankDebug:         {},
-}
diff --git a/contrib/go/_std_1.18/src/runtime/lockrank_off.go b/contrib/go/_std_1.18/src/runtime/lockrank_off.go
deleted file mode 100644
index daa45b542d..0000000000
--- a/contrib/go/_std_1.18/src/runtime/lockrank_off.go
+++ /dev/null
@@ -1,64 +0,0 @@
-// Copyright 2020 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build !goexperiment.staticlockranking
-
-package runtime
-
-// // lockRankStruct is embedded in mutex, but is empty when staticklockranking is
-// disabled (the default)
-type lockRankStruct struct {
-}
-
-func lockInit(l *mutex, rank lockRank) {
-}
-
-func getLockRank(l *mutex) lockRank {
-	return 0
-}
-
-func lockWithRank(l *mutex, rank lockRank) {
-	lock2(l)
-}
-
-// This function may be called in nosplit context and thus must be nosplit.
-//go:nosplit
-func acquireLockRank(rank lockRank) {
-}
-
-func unlockWithRank(l *mutex) {
-	unlock2(l)
-}
-
-// This function may be called in nosplit context and thus must be nosplit.
-//go:nosplit
-func releaseLockRank(rank lockRank) {
-}
-
-func lockWithRankMayAcquire(l *mutex, rank lockRank) {
-}
-
-//go:nosplit
-func assertLockHeld(l *mutex) {
-}
-
-//go:nosplit
-func assertRankHeld(r lockRank) {
-}
-
-//go:nosplit
-func worldStopped() {
-}
-
-//go:nosplit
-func worldStarted() {
-}
-
-//go:nosplit
-func assertWorldStopped() {
-}
-
-//go:nosplit
-func assertWorldStoppedOrLockHeld(l *mutex) {
-}
diff --git a/contrib/go/_std_1.18/src/runtime/malloc.go b/contrib/go/_std_1.18/src/runtime/malloc.go
deleted file mode 100644
index 6ed6ceade2..0000000000
--- a/contrib/go/_std_1.18/src/runtime/malloc.go
+++ /dev/null
@@ -1,1564 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Memory allocator.
-//
-// This was originally based on tcmalloc, but has diverged quite a bit.
-// http://goog-perftools.sourceforge.net/doc/tcmalloc.html
-
-// The main allocator works in runs of pages.
-// Small allocation sizes (up to and including 32 kB) are
-// rounded to one of about 70 size classes, each of which
-// has its own free set of objects of exactly that size.
-// Any free page of memory can be split into a set of objects
-// of one size class, which are then managed using a free bitmap.
-//
-// The allocator's data structures are:
-//
-//	fixalloc: a free-list allocator for fixed-size off-heap objects,
-//		used to manage storage used by the allocator.
-//	mheap: the malloc heap, managed at page (8192-byte) granularity.
-//	mspan: a run of in-use pages managed by the mheap.
-//	mcentral: collects all spans of a given size class.
-//	mcache: a per-P cache of mspans with free space.
-//	mstats: allocation statistics.
-//
-// Allocating a small object proceeds up a hierarchy of caches:
-//
-//	1. Round the size up to one of the small size classes
-//	   and look in the corresponding mspan in this P's mcache.
-//	   Scan the mspan's free bitmap to find a free slot.
-//	   If there is a free slot, allocate it.
-//	   This can all be done without acquiring a lock.
-//
-//	2. If the mspan has no free slots, obtain a new mspan
-//	   from the mcentral's list of mspans of the required size
-//	   class that have free space.
-//	   Obtaining a whole span amortizes the cost of locking
-//	   the mcentral.
-//
-//	3. If the mcentral's mspan list is empty, obtain a run
-//	   of pages from the mheap to use for the mspan.
-//
-//	4. If the mheap is empty or has no page runs large enough,
-//	   allocate a new group of pages (at least 1MB) from the
-//	   operating system. Allocating a large run of pages
-//	   amortizes the cost of talking to the operating system.
-//
-// Sweeping an mspan and freeing objects on it proceeds up a similar
-// hierarchy:
-//
-//	1. If the mspan is being swept in response to allocation, it
-//	   is returned to the mcache to satisfy the allocation.
-//
-//	2. Otherwise, if the mspan still has allocated objects in it,
-//	   it is placed on the mcentral free list for the mspan's size
-//	   class.
-//
-//	3. Otherwise, if all objects in the mspan are free, the mspan's
-//	   pages are returned to the mheap and the mspan is now dead.
-//
-// Allocating and freeing a large object uses the mheap
-// directly, bypassing the mcache and mcentral.
-//
-// If mspan.needzero is false, then free object slots in the mspan are
-// already zeroed. Otherwise if needzero is true, objects are zeroed as
-// they are allocated. There are various benefits to delaying zeroing
-// this way:
-//
-//	1. Stack frame allocation can avoid zeroing altogether.
-//
-//	2. It exhibits better temporal locality, since the program is
-//	   probably about to write to the memory.
-//
-//	3. We don't zero pages that never get reused.
-
-// Virtual memory layout
-//
-// The heap consists of a set of arenas, which are 64MB on 64-bit and
-// 4MB on 32-bit (heapArenaBytes). Each arena's start address is also
-// aligned to the arena size.
-//
-// Each arena has an associated heapArena object that stores the
-// metadata for that arena: the heap bitmap for all words in the arena
-// and the span map for all pages in the arena. heapArena objects are
-// themselves allocated off-heap.
-//
-// Since arenas are aligned, the address space can be viewed as a
-// series of arena frames. The arena map (mheap_.arenas) maps from
-// arena frame number to *heapArena, or nil for parts of the address
-// space not backed by the Go heap. The arena map is structured as a
-// two-level array consisting of a "L1" arena map and many "L2" arena
-// maps; however, since arenas are large, on many architectures, the
-// arena map consists of a single, large L2 map.
-//
-// The arena map covers the entire possible address space, allowing
-// the Go heap to use any part of the address space. The allocator
-// attempts to keep arenas contiguous so that large spans (and hence
-// large objects) can cross arenas.
-
-package runtime
-
-import (
-	"internal/goarch"
-	"internal/goos"
-	"runtime/internal/atomic"
-	"runtime/internal/math"
-	"runtime/internal/sys"
-	"unsafe"
-)
-
-const (
-	debugMalloc = false
-
-	maxTinySize   = _TinySize
-	tinySizeClass = _TinySizeClass
-	maxSmallSize  = _MaxSmallSize
-
-	pageShift = _PageShift
-	pageSize  = _PageSize
-	pageMask  = _PageMask
-	// By construction, single page spans of the smallest object class
-	// have the most objects per span.
-	maxObjsPerSpan = pageSize / 8
-
-	concurrentSweep = _ConcurrentSweep
-
-	_PageSize = 1 << _PageShift
-	_PageMask = _PageSize - 1
-
-	// _64bit = 1 on 64-bit systems, 0 on 32-bit systems
-	_64bit = 1 << (^uintptr(0) >> 63) / 2
-
-	// Tiny allocator parameters, see "Tiny allocator" comment in malloc.go.
-	_TinySize      = 16
-	_TinySizeClass = int8(2)
-
-	_FixAllocChunk = 16 << 10 // Chunk size for FixAlloc
-
-	// Per-P, per order stack segment cache size.
-	_StackCacheSize = 32 * 1024
-
-	// Number of orders that get caching. Order 0 is FixedStack
-	// and each successive order is twice as large.
-	// We want to cache 2KB, 4KB, 8KB, and 16KB stacks. Larger stacks
-	// will be allocated directly.
-	// Since FixedStack is different on different systems, we
-	// must vary NumStackOrders to keep the same maximum cached size.
-	//   OS               | FixedStack | NumStackOrders
-	//   -----------------+------------+---------------
-	//   linux/darwin/bsd | 2KB        | 4
-	//   windows/32       | 4KB        | 3
-	//   windows/64       | 8KB        | 2
-	//   plan9            | 4KB        | 3
-	_NumStackOrders = 4 - goarch.PtrSize/4*goos.IsWindows - 1*goos.IsPlan9
-
-	// heapAddrBits is the number of bits in a heap address. On
-	// amd64, addresses are sign-extended beyond heapAddrBits. On
-	// other arches, they are zero-extended.
-	//
-	// On most 64-bit platforms, we limit this to 48 bits based on a
-	// combination of hardware and OS limitations.
-	//
-	// amd64 hardware limits addresses to 48 bits, sign-extended
-	// to 64 bits. Addresses where the top 16 bits are not either
-	// all 0 or all 1 are "non-canonical" and invalid. Because of
-	// these "negative" addresses, we offset addresses by 1<<47
-	// (arenaBaseOffset) on amd64 before computing indexes into
-	// the heap arenas index. In 2017, amd64 hardware added
-	// support for 57 bit addresses; however, currently only Linux
-	// supports this extension and the kernel will never choose an
-	// address above 1<<47 unless mmap is called with a hint
-	// address above 1<<47 (which we never do).
-	//
-	// arm64 hardware (as of ARMv8) limits user addresses to 48
-	// bits, in the range [0, 1<<48).
-	//
-	// ppc64, mips64, and s390x support arbitrary 64 bit addresses
-	// in hardware. On Linux, Go leans on stricter OS limits. Based
-	// on Linux's processor.h, the user address space is limited as
-	// follows on 64-bit architectures:
-	//
-	// Architecture  Name              Maximum Value (exclusive)
-	// ---------------------------------------------------------------------
-	// amd64         TASK_SIZE_MAX     0x007ffffffff000 (47 bit addresses)
-	// arm64         TASK_SIZE_64      0x01000000000000 (48 bit addresses)
-	// ppc64{,le}    TASK_SIZE_USER64  0x00400000000000 (46 bit addresses)
-	// mips64{,le}   TASK_SIZE64       0x00010000000000 (40 bit addresses)
-	// s390x         TASK_SIZE         1<<64 (64 bit addresses)
-	//
-	// These limits may increase over time, but are currently at
-	// most 48 bits except on s390x. On all architectures, Linux
-	// starts placing mmap'd regions at addresses that are
-	// significantly below 48 bits, so even if it's possible to
-	// exceed Go's 48 bit limit, it's extremely unlikely in
-	// practice.
-	//
-	// On 32-bit platforms, we accept the full 32-bit address
-	// space because doing so is cheap.
-	// mips32 only has access to the low 2GB of virtual memory, so
-	// we further limit it to 31 bits.
-	//
-	// On ios/arm64, although 64-bit pointers are presumably
-	// available, pointers are truncated to 33 bits in iOS <14.
-	// Furthermore, only the top 4 GiB of the address space are
-	// actually available to the application. In iOS >=14, more
-	// of the address space is available, and the OS can now
-	// provide addresses outside of those 33 bits. Pick 40 bits
-	// as a reasonable balance between address space usage by the
-	// page allocator, and flexibility for what mmap'd regions
-	// we'll accept for the heap. We can't just move to the full
-	// 48 bits because this uses too much address space for older
-	// iOS versions.
-	// TODO(mknyszek): Once iOS <14 is deprecated, promote ios/arm64
-	// to a 48-bit address space like every other arm64 platform.
-	//
-	// WebAssembly currently has a limit of 4GB linear memory.
-	heapAddrBits = (_64bit*(1-goarch.IsWasm)*(1-goos.IsIos*goarch.IsArm64))*48 + (1-_64bit+goarch.IsWasm)*(32-(goarch.IsMips+goarch.IsMipsle)) + 40*goos.IsIos*goarch.IsArm64
-
-	// maxAlloc is the maximum size of an allocation. On 64-bit,
-	// it's theoretically possible to allocate 1<<heapAddrBits bytes. On
-	// 32-bit, however, this is one less than 1<<32 because the
-	// number of bytes in the address space doesn't actually fit
-	// in a uintptr.
-	maxAlloc = (1 << heapAddrBits) - (1-_64bit)*1
-
-	// The number of bits in a heap address, the size of heap
-	// arenas, and the L1 and L2 arena map sizes are related by
-	//
-	//   (1 << addr bits) = arena size * L1 entries * L2 entries
-	//
-	// Currently, we balance these as follows:
-	//
-	//       Platform  Addr bits  Arena size  L1 entries   L2 entries
-	// --------------  ---------  ----------  ----------  -----------
-	//       */64-bit         48        64MB           1    4M (32MB)
-	// windows/64-bit         48         4MB          64    1M  (8MB)
-	//      ios/arm64         33         4MB           1  2048  (8KB)
-	//       */32-bit         32         4MB           1  1024  (4KB)
-	//     */mips(le)         31         4MB           1   512  (2KB)
-
-	// heapArenaBytes is the size of a heap arena. The heap
-	// consists of mappings of size heapArenaBytes, aligned to
-	// heapArenaBytes. The initial heap mapping is one arena.
-	//
-	// This is currently 64MB on 64-bit non-Windows and 4MB on
-	// 32-bit and on Windows. We use smaller arenas on Windows
-	// because all committed memory is charged to the process,
-	// even if it's not touched. Hence, for processes with small
-	// heaps, the mapped arena space needs to be commensurate.
-	// This is particularly important with the race detector,
-	// since it significantly amplifies the cost of committed
-	// memory.
-	heapArenaBytes = 1 << logHeapArenaBytes
-
-	// logHeapArenaBytes is log_2 of heapArenaBytes. For clarity,
-	// prefer using heapArenaBytes where possible (we need the
-	// constant to compute some other constants).
-	logHeapArenaBytes = (6+20)*(_64bit*(1-goos.IsWindows)*(1-goarch.IsWasm)*(1-goos.IsIos*goarch.IsArm64)) + (2+20)*(_64bit*goos.IsWindows) + (2+20)*(1-_64bit) + (2+20)*goarch.IsWasm + (2+20)*goos.IsIos*goarch.IsArm64
-
-	// heapArenaBitmapBytes is the size of each heap arena's bitmap.
-	heapArenaBitmapBytes = heapArenaBytes / (goarch.PtrSize * 8 / 2)
-
-	pagesPerArena = heapArenaBytes / pageSize
-
-	// arenaL1Bits is the number of bits of the arena number
-	// covered by the first level arena map.
-	//
-	// This number should be small, since the first level arena
-	// map requires PtrSize*(1<<arenaL1Bits) of space in the
-	// binary's BSS. It can be zero, in which case the first level
-	// index is effectively unused. There is a performance benefit
-	// to this, since the generated code can be more efficient,
-	// but comes at the cost of having a large L2 mapping.
-	//
-	// We use the L1 map on 64-bit Windows because the arena size
-	// is small, but the address space is still 48 bits, and
-	// there's a high cost to having a large L2.
-	arenaL1Bits = 6 * (_64bit * goos.IsWindows)
-
-	// arenaL2Bits is the number of bits of the arena number
-	// covered by the second level arena index.
-	//
-	// The size of each arena map allocation is proportional to
-	// 1<<arenaL2Bits, so it's important that this not be too
-	// large. 48 bits leads to 32MB arena index allocations, which
-	// is about the practical threshold.
-	arenaL2Bits = heapAddrBits - logHeapArenaBytes - arenaL1Bits
-
-	// arenaL1Shift is the number of bits to shift an arena frame
-	// number by to compute an index into the first level arena map.
-	arenaL1Shift = arenaL2Bits
-
-	// arenaBits is the total bits in a combined arena map index.
-	// This is split between the index into the L1 arena map and
-	// the L2 arena map.
-	arenaBits = arenaL1Bits + arenaL2Bits
-
-	// arenaBaseOffset is the pointer value that corresponds to
-	// index 0 in the heap arena map.
-	//
-	// On amd64, the address space is 48 bits, sign extended to 64
-	// bits. This offset lets us handle "negative" addresses (or
-	// high addresses if viewed as unsigned).
-	//
-	// On aix/ppc64, this offset allows to keep the heapAddrBits to
-	// 48. Otherwise, it would be 60 in order to handle mmap addresses
-	// (in range 0x0a00000000000000 - 0x0afffffffffffff). But in this
-	// case, the memory reserved in (s *pageAlloc).init for chunks
-	// is causing important slowdowns.
-	//
-	// On other platforms, the user address space is contiguous
-	// and starts at 0, so no offset is necessary.
-	arenaBaseOffset = 0xffff800000000000*goarch.IsAmd64 + 0x0a00000000000000*goos.IsAix
-	// A typed version of this constant that will make it into DWARF (for viewcore).
-	arenaBaseOffsetUintptr = uintptr(arenaBaseOffset)
-
-	// Max number of threads to run garbage collection.
-	// 2, 3, and 4 are all plausible maximums depending
-	// on the hardware details of the machine. The garbage
-	// collector scales well to 32 cpus.
-	_MaxGcproc = 32
-
-	// minLegalPointer is the smallest possible legal pointer.
-	// This is the smallest possible architectural page size,
-	// since we assume that the first page is never mapped.
-	//
-	// This should agree with minZeroPage in the compiler.
-	minLegalPointer uintptr = 4096
-)
-
-// physPageSize is the size in bytes of the OS's physical pages.
-// Mapping and unmapping operations must be done at multiples of
-// physPageSize.
-//
-// This must be set by the OS init code (typically in osinit) before
-// mallocinit.
-var physPageSize uintptr
-
-// physHugePageSize is the size in bytes of the OS's default physical huge
-// page size whose allocation is opaque to the application. It is assumed
-// and verified to be a power of two.
-//
-// If set, this must be set by the OS init code (typically in osinit) before
-// mallocinit. However, setting it at all is optional, and leaving the default
-// value is always safe (though potentially less efficient).
-//
-// Since physHugePageSize is always assumed to be a power of two,
-// physHugePageShift is defined as physHugePageSize == 1 << physHugePageShift.
-// The purpose of physHugePageShift is to avoid doing divisions in
-// performance critical functions.
-var (
-	physHugePageSize  uintptr
-	physHugePageShift uint
-)
-
-// OS memory management abstraction layer
-//
-// Regions of the address space managed by the runtime may be in one of four
-// states at any given time:
-// 1) None - Unreserved and unmapped, the default state of any region.
-// 2) Reserved - Owned by the runtime, but accessing it would cause a fault.
-//               Does not count against the process' memory footprint.
-// 3) Prepared - Reserved, intended not to be backed by physical memory (though
-//               an OS may implement this lazily). Can transition efficiently to
-//               Ready. Accessing memory in such a region is undefined (may
-//               fault, may give back unexpected zeroes, etc.).
-// 4) Ready - may be accessed safely.
-//
-// This set of states is more than is strictly necessary to support all the
-// currently supported platforms. One could get by with just None, Reserved, and
-// Ready. However, the Prepared state gives us flexibility for performance
-// purposes. For example, on POSIX-y operating systems, Reserved is usually a
-// private anonymous mmap'd region with PROT_NONE set, and to transition
-// to Ready would require setting PROT_READ|PROT_WRITE. However the
-// underspecification of Prepared lets us use just MADV_FREE to transition from
-// Ready to Prepared. Thus with the Prepared state we can set the permission
-// bits just once early on, we can efficiently tell the OS that it's free to
-// take pages away from us when we don't strictly need them.
-//
-// For each OS there is a common set of helpers defined that transition
-// memory regions between these states. The helpers are as follows:
-//
-// sysAlloc transitions an OS-chosen region of memory from None to Ready.
-// More specifically, it obtains a large chunk of zeroed memory from the
-// operating system, typically on the order of a hundred kilobytes
-// or a megabyte. This memory is always immediately available for use.
-//
-// sysFree transitions a memory region from any state to None. Therefore, it
-// returns memory unconditionally. It is used if an out-of-memory error has been
-// detected midway through an allocation or to carve out an aligned section of
-// the address space. It is okay if sysFree is a no-op only if sysReserve always
-// returns a memory region aligned to the heap allocator's alignment
-// restrictions.
-//
-// sysReserve transitions a memory region from None to Reserved. It reserves
-// address space in such a way that it would cause a fatal fault upon access
-// (either via permissions or not committing the memory). Such a reservation is
-// thus never backed by physical memory.
-// If the pointer passed to it is non-nil, the caller wants the
-// reservation there, but sysReserve can still choose another
-// location if that one is unavailable.
-// NOTE: sysReserve returns OS-aligned memory, but the heap allocator
-// may use larger alignment, so the caller must be careful to realign the
-// memory obtained by sysReserve.
-//
-// sysMap transitions a memory region from Reserved to Prepared. It ensures the
-// memory region can be efficiently transitioned to Ready.
-//
-// sysUsed transitions a memory region from Prepared to Ready. It notifies the
-// operating system that the memory region is needed and ensures that the region
-// may be safely accessed. This is typically a no-op on systems that don't have
-// an explicit commit step and hard over-commit limits, but is critical on
-// Windows, for example.
-//
-// sysUnused transitions a memory region from Ready to Prepared. It notifies the
-// operating system that the physical pages backing this memory region are no
-// longer needed and can be reused for other purposes. The contents of a
-// sysUnused memory region are considered forfeit and the region must not be
-// accessed again until sysUsed is called.
-//
-// sysFault transitions a memory region from Ready or Prepared to Reserved. It
-// marks a region such that it will always fault if accessed. Used only for
-// debugging the runtime.
-
-func mallocinit() {
-	if class_to_size[_TinySizeClass] != _TinySize {
-		throw("bad TinySizeClass")
-	}
-
-	if heapArenaBitmapBytes&(heapArenaBitmapBytes-1) != 0 {
-		// heapBits expects modular arithmetic on bitmap
-		// addresses to work.
-		throw("heapArenaBitmapBytes not a power of 2")
-	}
-
-	// Copy class sizes out for statistics table.
-	for i := range class_to_size {
-		memstats.by_size[i].size = uint32(class_to_size[i])
-	}
-
-	// Check physPageSize.
-	if physPageSize == 0 {
-		// The OS init code failed to fetch the physical page size.
-		throw("failed to get system page size")
-	}
-	if physPageSize > maxPhysPageSize {
-		print("system page size (", physPageSize, ") is larger than maximum page size (", maxPhysPageSize, ")\n")
-		throw("bad system page size")
-	}
-	if physPageSize < minPhysPageSize {
-		print("system page size (", physPageSize, ") is smaller than minimum page size (", minPhysPageSize, ")\n")
-		throw("bad system page size")
-	}
-	if physPageSize&(physPageSize-1) != 0 {
-		print("system page size (", physPageSize, ") must be a power of 2\n")
-		throw("bad system page size")
-	}
-	if physHugePageSize&(physHugePageSize-1) != 0 {
-		print("system huge page size (", physHugePageSize, ") must be a power of 2\n")
-		throw("bad system huge page size")
-	}
-	if physHugePageSize > maxPhysHugePageSize {
-		// physHugePageSize is greater than the maximum supported huge page size.
-		// Don't throw here, like in the other cases, since a system configured
-		// in this way isn't wrong, we just don't have the code to support them.
-		// Instead, silently set the huge page size to zero.
-		physHugePageSize = 0
-	}
-	if physHugePageSize != 0 {
-		// Since physHugePageSize is a power of 2, it suffices to increase
-		// physHugePageShift until 1<<physHugePageShift == physHugePageSize.
-		for 1<<physHugePageShift != physHugePageSize {
-			physHugePageShift++
-		}
-	}
-	if pagesPerArena%pagesPerSpanRoot != 0 {
-		print("pagesPerArena (", pagesPerArena, ") is not divisible by pagesPerSpanRoot (", pagesPerSpanRoot, ")\n")
-		throw("bad pagesPerSpanRoot")
-	}
-	if pagesPerArena%pagesPerReclaimerChunk != 0 {
-		print("pagesPerArena (", pagesPerArena, ") is not divisible by pagesPerReclaimerChunk (", pagesPerReclaimerChunk, ")\n")
-		throw("bad pagesPerReclaimerChunk")
-	}
-
-	// Initialize the heap.
-	mheap_.init()
-	mcache0 = allocmcache()
-	lockInit(&gcBitsArenas.lock, lockRankGcBitsArenas)
-	lockInit(&proflock, lockRankProf)
-	lockInit(&globalAlloc.mutex, lockRankGlobalAlloc)
-
-	// Create initial arena growth hints.
-	if goarch.PtrSize == 8 {
-		// On a 64-bit machine, we pick the following hints
-		// because:
-		//
-		// 1. Starting from the middle of the address space
-		// makes it easier to grow out a contiguous range
-		// without running in to some other mapping.
-		//
-		// 2. This makes Go heap addresses more easily
-		// recognizable when debugging.
-		//
-		// 3. Stack scanning in gccgo is still conservative,
-		// so it's important that addresses be distinguishable
-		// from other data.
-		//
-		// Starting at 0x00c0 means that the valid memory addresses
-		// will begin 0x00c0, 0x00c1, ...
-		// In little-endian, that's c0 00, c1 00, ... None of those are valid
-		// UTF-8 sequences, and they are otherwise as far away from
-		// ff (likely a common byte) as possible. If that fails, we try other 0xXXc0
-		// addresses. An earlier attempt to use 0x11f8 caused out of memory errors
-		// on OS X during thread allocations.  0x00c0 causes conflicts with
-		// AddressSanitizer which reserves all memory up to 0x0100.
-		// These choices reduce the odds of a conservative garbage collector
-		// not collecting memory because some non-pointer block of memory
-		// had a bit pattern that matched a memory address.
-		//
-		// However, on arm64, we ignore all this advice above and slam the
-		// allocation at 0x40 << 32 because when using 4k pages with 3-level
-		// translation buffers, the user address space is limited to 39 bits
-		// On ios/arm64, the address space is even smaller.
-		//
-		// On AIX, mmaps starts at 0x0A00000000000000 for 64-bit.
-		// processes.
-		for i := 0x7f; i >= 0; i-- {
-			var p uintptr
-			switch {
-			case raceenabled:
-				// The TSAN runtime requires the heap
-				// to be in the range [0x00c000000000,
-				// 0x00e000000000).
-				p = uintptr(i)<<32 | uintptrMask&(0x00c0<<32)
-				if p >= uintptrMask&0x00e000000000 {
-					continue
-				}
-			case GOARCH == "arm64" && GOOS == "ios":
-				p = uintptr(i)<<40 | uintptrMask&(0x0013<<28)
-			case GOARCH == "arm64":
-				p = uintptr(i)<<40 | uintptrMask&(0x0040<<32)
-			case GOOS == "aix":
-				if i == 0 {
-					// We don't use addresses directly after 0x0A00000000000000
-					// to avoid collisions with others mmaps done by non-go programs.
-					continue
-				}
-				p = uintptr(i)<<40 | uintptrMask&(0xa0<<52)
-			default:
-				p = uintptr(i)<<40 | uintptrMask&(0x00c0<<32)
-			}
-			hint := (*arenaHint)(mheap_.arenaHintAlloc.alloc())
-			hint.addr = p
-			hint.next, mheap_.arenaHints = mheap_.arenaHints, hint
-		}
-	} else {
-		// On a 32-bit machine, we're much more concerned
-		// about keeping the usable heap contiguous.
-		// Hence:
-		//
-		// 1. We reserve space for all heapArenas up front so
-		// they don't get interleaved with the heap. They're
-		// ~258MB, so this isn't too bad. (We could reserve a
-		// smaller amount of space up front if this is a
-		// problem.)
-		//
-		// 2. We hint the heap to start right above the end of
-		// the binary so we have the best chance of keeping it
-		// contiguous.
-		//
-		// 3. We try to stake out a reasonably large initial
-		// heap reservation.
-
-		const arenaMetaSize = (1 << arenaBits) * unsafe.Sizeof(heapArena{})
-		meta := uintptr(sysReserve(nil, arenaMetaSize))
-		if meta != 0 {
-			mheap_.heapArenaAlloc.init(meta, arenaMetaSize, true)
-		}
-
-		// We want to start the arena low, but if we're linked
-		// against C code, it's possible global constructors
-		// have called malloc and adjusted the process' brk.
-		// Query the brk so we can avoid trying to map the
-		// region over it (which will cause the kernel to put
-		// the region somewhere else, likely at a high
-		// address).
-		procBrk := sbrk0()
-
-		// If we ask for the end of the data segment but the
-		// operating system requires a little more space
-		// before we can start allocating, it will give out a
-		// slightly higher pointer. Except QEMU, which is
-		// buggy, as usual: it won't adjust the pointer
-		// upward. So adjust it upward a little bit ourselves:
-		// 1/4 MB to get away from the running binary image.
-		p := firstmoduledata.end
-		if p < procBrk {
-			p = procBrk
-		}
-		if mheap_.heapArenaAlloc.next <= p && p < mheap_.heapArenaAlloc.end {
-			p = mheap_.heapArenaAlloc.end
-		}
-		p = alignUp(p+(256<<10), heapArenaBytes)
-		// Because we're worried about fragmentation on
-		// 32-bit, we try to make a large initial reservation.
-		arenaSizes := []uintptr{
-			512 << 20,
-			256 << 20,
-			128 << 20,
-		}
-		for _, arenaSize := range arenaSizes {
-			a, size := sysReserveAligned(unsafe.Pointer(p), arenaSize, heapArenaBytes)
-			if a != nil {
-				mheap_.arena.init(uintptr(a), size, false)
-				p = mheap_.arena.end // For hint below
-				break
-			}
-		}
-		hint := (*arenaHint)(mheap_.arenaHintAlloc.alloc())
-		hint.addr = p
-		hint.next, mheap_.arenaHints = mheap_.arenaHints, hint
-	}
-}
-
-// sysAlloc allocates heap arena space for at least n bytes. The
-// returned pointer is always heapArenaBytes-aligned and backed by
-// h.arenas metadata. The returned size is always a multiple of
-// heapArenaBytes. sysAlloc returns nil on failure.
-// There is no corresponding free function.
-//
-// sysAlloc returns a memory region in the Reserved state. This region must
-// be transitioned to Prepared and then Ready before use.
-//
-// h must be locked.
-func (h *mheap) sysAlloc(n uintptr) (v unsafe.Pointer, size uintptr) {
-	assertLockHeld(&h.lock)
-
-	n = alignUp(n, heapArenaBytes)
-
-	// First, try the arena pre-reservation.
-	v = h.arena.alloc(n, heapArenaBytes, &memstats.heap_sys)
-	if v != nil {
-		size = n
-		goto mapped
-	}
-
-	// Try to grow the heap at a hint address.
-	for h.arenaHints != nil {
-		hint := h.arenaHints
-		p := hint.addr
-		if hint.down {
-			p -= n
-		}
-		if p+n < p {
-			// We can't use this, so don't ask.
-			v = nil
-		} else if arenaIndex(p+n-1) >= 1<<arenaBits {
-			// Outside addressable heap. Can't use.
-			v = nil
-		} else {
-			v = sysReserve(unsafe.Pointer(p), n)
-		}
-		if p == uintptr(v) {
-			// Success. Update the hint.
-			if !hint.down {
-				p += n
-			}
-			hint.addr = p
-			size = n
-			break
-		}
-		// Failed. Discard this hint and try the next.
-		//
-		// TODO: This would be cleaner if sysReserve could be
-		// told to only return the requested address. In
-		// particular, this is already how Windows behaves, so
-		// it would simplify things there.
-		if v != nil {
-			sysFree(v, n, nil)
-		}
-		h.arenaHints = hint.next
-		h.arenaHintAlloc.free(unsafe.Pointer(hint))
-	}
-
-	if size == 0 {
-		if raceenabled {
-			// The race detector assumes the heap lives in
-			// [0x00c000000000, 0x00e000000000), but we
-			// just ran out of hints in this region. Give
-			// a nice failure.
-			throw("too many address space collisions for -race mode")
-		}
-
-		// All of the hints failed, so we'll take any
-		// (sufficiently aligned) address the kernel will give
-		// us.
-		v, size = sysReserveAligned(nil, n, heapArenaBytes)
-		if v == nil {
-			return nil, 0
-		}
-
-		// Create new hints for extending this region.
-		hint := (*arenaHint)(h.arenaHintAlloc.alloc())
-		hint.addr, hint.down = uintptr(v), true
-		hint.next, mheap_.arenaHints = mheap_.arenaHints, hint
-		hint = (*arenaHint)(h.arenaHintAlloc.alloc())
-		hint.addr = uintptr(v) + size
-		hint.next, mheap_.arenaHints = mheap_.arenaHints, hint
-	}
-
-	// Check for bad pointers or pointers we can't use.
-	{
-		var bad string
-		p := uintptr(v)
-		if p+size < p {
-			bad = "region exceeds uintptr range"
-		} else if arenaIndex(p) >= 1<<arenaBits {
-			bad = "base outside usable address space"
-		} else if arenaIndex(p+size-1) >= 1<<arenaBits {
-			bad = "end outside usable address space"
-		}
-		if bad != "" {
-			// This should be impossible on most architectures,
-			// but it would be really confusing to debug.
-			print("runtime: memory allocated by OS [", hex(p), ", ", hex(p+size), ") not in usable address space: ", bad, "\n")
-			throw("memory reservation exceeds address space limit")
-		}
-	}
-
-	if uintptr(v)&(heapArenaBytes-1) != 0 {
-		throw("misrounded allocation in sysAlloc")
-	}
-
-mapped:
-	// Create arena metadata.
-	for ri := arenaIndex(uintptr(v)); ri <= arenaIndex(uintptr(v)+size-1); ri++ {
-		l2 := h.arenas[ri.l1()]
-		if l2 == nil {
-			// Allocate an L2 arena map.
-			l2 = (*[1 << arenaL2Bits]*heapArena)(persistentalloc(unsafe.Sizeof(*l2), goarch.PtrSize, nil))
-			if l2 == nil {
-				throw("out of memory allocating heap arena map")
-			}
-			atomic.StorepNoWB(unsafe.Pointer(&h.arenas[ri.l1()]), unsafe.Pointer(l2))
-		}
-
-		if l2[ri.l2()] != nil {
-			throw("arena already initialized")
-		}
-		var r *heapArena
-		r = (*heapArena)(h.heapArenaAlloc.alloc(unsafe.Sizeof(*r), goarch.PtrSize, &memstats.gcMiscSys))
-		if r == nil {
-			r = (*heapArena)(persistentalloc(unsafe.Sizeof(*r), goarch.PtrSize, &memstats.gcMiscSys))
-			if r == nil {
-				throw("out of memory allocating heap arena metadata")
-			}
-		}
-
-		// Add the arena to the arenas list.
-		if len(h.allArenas) == cap(h.allArenas) {
-			size := 2 * uintptr(cap(h.allArenas)) * goarch.PtrSize
-			if size == 0 {
-				size = physPageSize
-			}
-			newArray := (*notInHeap)(persistentalloc(size, goarch.PtrSize, &memstats.gcMiscSys))
-			if newArray == nil {
-				throw("out of memory allocating allArenas")
-			}
-			oldSlice := h.allArenas
-			*(*notInHeapSlice)(unsafe.Pointer(&h.allArenas)) = notInHeapSlice{newArray, len(h.allArenas), int(size / goarch.PtrSize)}
-			copy(h.allArenas, oldSlice)
-			// Do not free the old backing array because
-			// there may be concurrent readers. Since we
-			// double the array each time, this can lead
-			// to at most 2x waste.
-		}
-		h.allArenas = h.allArenas[:len(h.allArenas)+1]
-		h.allArenas[len(h.allArenas)-1] = ri
-
-		// Store atomically just in case an object from the
-		// new heap arena becomes visible before the heap lock
-		// is released (which shouldn't happen, but there's
-		// little downside to this).
-		atomic.StorepNoWB(unsafe.Pointer(&l2[ri.l2()]), unsafe.Pointer(r))
-	}
-
-	// Tell the race detector about the new heap memory.
-	if raceenabled {
-		racemapshadow(v, size)
-	}
-
-	return
-}
-
-// sysReserveAligned is like sysReserve, but the returned pointer is
-// aligned to align bytes. It may reserve either n or n+align bytes,
-// so it returns the size that was reserved.
-func sysReserveAligned(v unsafe.Pointer, size, align uintptr) (unsafe.Pointer, uintptr) {
-	// Since the alignment is rather large in uses of this
-	// function, we're not likely to get it by chance, so we ask
-	// for a larger region and remove the parts we don't need.
-	retries := 0
-retry:
-	p := uintptr(sysReserve(v, size+align))
-	switch {
-	case p == 0:
-		return nil, 0
-	case p&(align-1) == 0:
-		// We got lucky and got an aligned region, so we can
-		// use the whole thing.
-		return unsafe.Pointer(p), size + align
-	case GOOS == "windows":
-		// On Windows we can't release pieces of a
-		// reservation, so we release the whole thing and
-		// re-reserve the aligned sub-region. This may race,
-		// so we may have to try again.
-		sysFree(unsafe.Pointer(p), size+align, nil)
-		p = alignUp(p, align)
-		p2 := sysReserve(unsafe.Pointer(p), size)
-		if p != uintptr(p2) {
-			// Must have raced. Try again.
-			sysFree(p2, size, nil)
-			if retries++; retries == 100 {
-				throw("failed to allocate aligned heap memory; too many retries")
-			}
-			goto retry
-		}
-		// Success.
-		return p2, size
-	default:
-		// Trim off the unaligned parts.
-		pAligned := alignUp(p, align)
-		sysFree(unsafe.Pointer(p), pAligned-p, nil)
-		end := pAligned + size
-		endLen := (p + size + align) - end
-		if endLen > 0 {
-			sysFree(unsafe.Pointer(end), endLen, nil)
-		}
-		return unsafe.Pointer(pAligned), size
-	}
-}
-
-// base address for all 0-byte allocations
-var zerobase uintptr
-
-// nextFreeFast returns the next free object if one is quickly available.
-// Otherwise it returns 0.
-func nextFreeFast(s *mspan) gclinkptr {
-	theBit := sys.Ctz64(s.allocCache) // Is there a free object in the allocCache?
-	if theBit < 64 {
-		result := s.freeindex + uintptr(theBit)
-		if result < s.nelems {
-			freeidx := result + 1
-			if freeidx%64 == 0 && freeidx != s.nelems {
-				return 0
-			}
-			s.allocCache >>= uint(theBit + 1)
-			s.freeindex = freeidx
-			s.allocCount++
-			return gclinkptr(result*s.elemsize + s.base())
-		}
-	}
-	return 0
-}
-
-// nextFree returns the next free object from the cached span if one is available.
-// Otherwise it refills the cache with a span with an available object and
-// returns that object along with a flag indicating that this was a heavy
-// weight allocation. If it is a heavy weight allocation the caller must
-// determine whether a new GC cycle needs to be started or if the GC is active
-// whether this goroutine needs to assist the GC.
-//
-// Must run in a non-preemptible context since otherwise the owner of
-// c could change.
-func (c *mcache) nextFree(spc spanClass) (v gclinkptr, s *mspan, shouldhelpgc bool) {
-	s = c.alloc[spc]
-	shouldhelpgc = false
-	freeIndex := s.nextFreeIndex()
-	if freeIndex == s.nelems {
-		// The span is full.
-		if uintptr(s.allocCount) != s.nelems {
-			println("runtime: s.allocCount=", s.allocCount, "s.nelems=", s.nelems)
-			throw("s.allocCount != s.nelems && freeIndex == s.nelems")
-		}
-		c.refill(spc)
-		shouldhelpgc = true
-		s = c.alloc[spc]
-
-		freeIndex = s.nextFreeIndex()
-	}
-
-	if freeIndex >= s.nelems {
-		throw("freeIndex is not valid")
-	}
-
-	v = gclinkptr(freeIndex*s.elemsize + s.base())
-	s.allocCount++
-	if uintptr(s.allocCount) > s.nelems {
-		println("s.allocCount=", s.allocCount, "s.nelems=", s.nelems)
-		throw("s.allocCount > s.nelems")
-	}
-	return
-}
-
-// Allocate an object of size bytes.
-// Small objects are allocated from the per-P cache's free lists.
-// Large objects (> 32 kB) are allocated straight from the heap.
-func mallocgc(size uintptr, typ *_type, needzero bool) unsafe.Pointer {
-	if gcphase == _GCmarktermination {
-		throw("mallocgc called with gcphase == _GCmarktermination")
-	}
-
-	if size == 0 {
-		return unsafe.Pointer(&zerobase)
-	}
-	userSize := size
-	if asanenabled {
-		// Refer to ASAN runtime library, the malloc() function allocates extra memory,
-		// the redzone, around the user requested memory region. And the redzones are marked
-		// as unaddressable. We perform the same operations in Go to detect the overflows or
-		// underflows.
-		size += computeRZlog(size)
-	}
-
-	if debug.malloc {
-		if debug.sbrk != 0 {
-			align := uintptr(16)
-			if typ != nil {
-				// TODO(austin): This should be just
-				//   align = uintptr(typ.align)
-				// but that's only 4 on 32-bit platforms,
-				// even if there's a uint64 field in typ (see #599).
-				// This causes 64-bit atomic accesses to panic.
-				// Hence, we use stricter alignment that matches
-				// the normal allocator better.
-				if size&7 == 0 {
-					align = 8
-				} else if size&3 == 0 {
-					align = 4
-				} else if size&1 == 0 {
-					align = 2
-				} else {
-					align = 1
-				}
-			}
-			return persistentalloc(size, align, &memstats.other_sys)
-		}
-
-		if inittrace.active && inittrace.id == getg().goid {
-			// Init functions are executed sequentially in a single goroutine.
-			inittrace.allocs += 1
-		}
-	}
-
-	// assistG is the G to charge for this allocation, or nil if
-	// GC is not currently active.
-	var assistG *g
-	if gcBlackenEnabled != 0 {
-		// Charge the current user G for this allocation.
-		assistG = getg()
-		if assistG.m.curg != nil {
-			assistG = assistG.m.curg
-		}
-		// Charge the allocation against the G. We'll account
-		// for internal fragmentation at the end of mallocgc.
-		assistG.gcAssistBytes -= int64(size)
-
-		if assistG.gcAssistBytes < 0 {
-			// This G is in debt. Assist the GC to correct
-			// this before allocating. This must happen
-			// before disabling preemption.
-			gcAssistAlloc(assistG)
-		}
-	}
-
-	// Set mp.mallocing to keep from being preempted by GC.
-	mp := acquirem()
-	if mp.mallocing != 0 {
-		throw("malloc deadlock")
-	}
-	if mp.gsignal == getg() {
-		throw("malloc during signal")
-	}
-	mp.mallocing = 1
-
-	shouldhelpgc := false
-	dataSize := userSize
-	c := getMCache(mp)
-	if c == nil {
-		throw("mallocgc called without a P or outside bootstrapping")
-	}
-	var span *mspan
-	var x unsafe.Pointer
-	noscan := typ == nil || typ.ptrdata == 0
-	// In some cases block zeroing can profitably (for latency reduction purposes)
-	// be delayed till preemption is possible; delayedZeroing tracks that state.
-	delayedZeroing := false
-	if size <= maxSmallSize {
-		if noscan && size < maxTinySize {
-			// Tiny allocator.
-			//
-			// Tiny allocator combines several tiny allocation requests
-			// into a single memory block. The resulting memory block
-			// is freed when all subobjects are unreachable. The subobjects
-			// must be noscan (don't have pointers), this ensures that
-			// the amount of potentially wasted memory is bounded.
-			//
-			// Size of the memory block used for combining (maxTinySize) is tunable.
-			// Current setting is 16 bytes, which relates to 2x worst case memory
-			// wastage (when all but one subobjects are unreachable).
-			// 8 bytes would result in no wastage at all, but provides less
-			// opportunities for combining.
-			// 32 bytes provides more opportunities for combining,
-			// but can lead to 4x worst case wastage.
-			// The best case winning is 8x regardless of block size.
-			//
-			// Objects obtained from tiny allocator must not be freed explicitly.
-			// So when an object will be freed explicitly, we ensure that
-			// its size >= maxTinySize.
-			//
-			// SetFinalizer has a special case for objects potentially coming
-			// from tiny allocator, it such case it allows to set finalizers
-			// for an inner byte of a memory block.
-			//
-			// The main targets of tiny allocator are small strings and
-			// standalone escaping variables. On a json benchmark
-			// the allocator reduces number of allocations by ~12% and
-			// reduces heap size by ~20%.
-			off := c.tinyoffset
-			// Align tiny pointer for required (conservative) alignment.
-			if size&7 == 0 {
-				off = alignUp(off, 8)
-			} else if goarch.PtrSize == 4 && size == 12 {
-				// Conservatively align 12-byte objects to 8 bytes on 32-bit
-				// systems so that objects whose first field is a 64-bit
-				// value is aligned to 8 bytes and does not cause a fault on
-				// atomic access. See issue 37262.
-				// TODO(mknyszek): Remove this workaround if/when issue 36606
-				// is resolved.
-				off = alignUp(off, 8)
-			} else if size&3 == 0 {
-				off = alignUp(off, 4)
-			} else if size&1 == 0 {
-				off = alignUp(off, 2)
-			}
-			if off+size <= maxTinySize && c.tiny != 0 {
-				// The object fits into existing tiny block.
-				x = unsafe.Pointer(c.tiny + off)
-				c.tinyoffset = off + size
-				c.tinyAllocs++
-				mp.mallocing = 0
-				releasem(mp)
-				return x
-			}
-			// Allocate a new maxTinySize block.
-			span = c.alloc[tinySpanClass]
-			v := nextFreeFast(span)
-			if v == 0 {
-				v, span, shouldhelpgc = c.nextFree(tinySpanClass)
-			}
-			x = unsafe.Pointer(v)
-			(*[2]uint64)(x)[0] = 0
-			(*[2]uint64)(x)[1] = 0
-			// See if we need to replace the existing tiny block with the new one
-			// based on amount of remaining free space.
-			if !raceenabled && (size < c.tinyoffset || c.tiny == 0) {
-				// Note: disabled when race detector is on, see comment near end of this function.
-				c.tiny = uintptr(x)
-				c.tinyoffset = size
-			}
-			size = maxTinySize
-		} else {
-			var sizeclass uint8
-			if size <= smallSizeMax-8 {
-				sizeclass = size_to_class8[divRoundUp(size, smallSizeDiv)]
-			} else {
-				sizeclass = size_to_class128[divRoundUp(size-smallSizeMax, largeSizeDiv)]
-			}
-			size = uintptr(class_to_size[sizeclass])
-			spc := makeSpanClass(sizeclass, noscan)
-			span = c.alloc[spc]
-			v := nextFreeFast(span)
-			if v == 0 {
-				v, span, shouldhelpgc = c.nextFree(spc)
-			}
-			x = unsafe.Pointer(v)
-			if needzero && span.needzero != 0 {
-				memclrNoHeapPointers(unsafe.Pointer(v), size)
-			}
-		}
-	} else {
-		shouldhelpgc = true
-		// For large allocations, keep track of zeroed state so that
-		// bulk zeroing can be happen later in a preemptible context.
-		span = c.allocLarge(size, noscan)
-		span.freeindex = 1
-		span.allocCount = 1
-		size = span.elemsize
-		x = unsafe.Pointer(span.base())
-		if needzero && span.needzero != 0 {
-			if noscan {
-				delayedZeroing = true
-			} else {
-				memclrNoHeapPointers(x, size)
-				// We've in theory cleared almost the whole span here,
-				// and could take the extra step of actually clearing
-				// the whole thing. However, don't. Any GC bits for the
-				// uncleared parts will be zero, and it's just going to
-				// be needzero = 1 once freed anyway.
-			}
-		}
-	}
-
-	var scanSize uintptr
-	if !noscan {
-		heapBitsSetType(uintptr(x), size, dataSize, typ)
-		if dataSize > typ.size {
-			// Array allocation. If there are any
-			// pointers, GC has to scan to the last
-			// element.
-			if typ.ptrdata != 0 {
-				scanSize = dataSize - typ.size + typ.ptrdata
-			}
-		} else {
-			scanSize = typ.ptrdata
-		}
-		c.scanAlloc += scanSize
-	}
-
-	// Ensure that the stores above that initialize x to
-	// type-safe memory and set the heap bits occur before
-	// the caller can make x observable to the garbage
-	// collector. Otherwise, on weakly ordered machines,
-	// the garbage collector could follow a pointer to x,
-	// but see uninitialized memory or stale heap bits.
-	publicationBarrier()
-
-	// Allocate black during GC.
-	// All slots hold nil so no scanning is needed.
-	// This may be racing with GC so do it atomically if there can be
-	// a race marking the bit.
-	if gcphase != _GCoff {
-		gcmarknewobject(span, uintptr(x), size, scanSize)
-	}
-
-	if raceenabled {
-		racemalloc(x, size)
-	}
-
-	if msanenabled {
-		msanmalloc(x, size)
-	}
-
-	if asanenabled {
-		// We should only read/write the memory with the size asked by the user.
-		// The rest of the allocated memory should be poisoned, so that we can report
-		// errors when accessing poisoned memory.
-		// The allocated memory is larger than required userSize, it will also include
-		// redzone and some other padding bytes.
-		rzBeg := unsafe.Add(x, userSize)
-		asanpoison(rzBeg, size-userSize)
-		asanunpoison(x, userSize)
-	}
-
-	if rate := MemProfileRate; rate > 0 {
-		// Note cache c only valid while m acquired; see #47302
-		if rate != 1 && size < c.nextSample {
-			c.nextSample -= size
-		} else {
-			profilealloc(mp, x, size)
-		}
-	}
-	mp.mallocing = 0
-	releasem(mp)
-
-	// Pointerfree data can be zeroed late in a context where preemption can occur.
-	// x will keep the memory alive.
-	if delayedZeroing {
-		if !noscan {
-			throw("delayed zeroing on data that may contain pointers")
-		}
-		memclrNoHeapPointersChunked(size, x) // This is a possible preemption point: see #47302
-	}
-
-	if debug.malloc {
-		if debug.allocfreetrace != 0 {
-			tracealloc(x, size, typ)
-		}
-
-		if inittrace.active && inittrace.id == getg().goid {
-			// Init functions are executed sequentially in a single goroutine.
-			inittrace.bytes += uint64(size)
-		}
-	}
-
-	if assistG != nil {
-		// Account for internal fragmentation in the assist
-		// debt now that we know it.
-		assistG.gcAssistBytes -= int64(size - dataSize)
-	}
-
-	if shouldhelpgc {
-		if t := (gcTrigger{kind: gcTriggerHeap}); t.test() {
-			gcStart(t)
-		}
-	}
-
-	if raceenabled && noscan && dataSize < maxTinySize {
-		// Pad tinysize allocations so they are aligned with the end
-		// of the tinyalloc region. This ensures that any arithmetic
-		// that goes off the top end of the object will be detectable
-		// by checkptr (issue 38872).
-		// Note that we disable tinyalloc when raceenabled for this to work.
-		// TODO: This padding is only performed when the race detector
-		// is enabled. It would be nice to enable it if any package
-		// was compiled with checkptr, but there's no easy way to
-		// detect that (especially at compile time).
-		// TODO: enable this padding for all allocations, not just
-		// tinyalloc ones. It's tricky because of pointer maps.
-		// Maybe just all noscan objects?
-		x = add(x, size-dataSize)
-	}
-
-	return x
-}
-
-// memclrNoHeapPointersChunked repeatedly calls memclrNoHeapPointers
-// on chunks of the buffer to be zeroed, with opportunities for preemption
-// along the way.  memclrNoHeapPointers contains no safepoints and also
-// cannot be preemptively scheduled, so this provides a still-efficient
-// block copy that can also be preempted on a reasonable granularity.
-//
-// Use this with care; if the data being cleared is tagged to contain
-// pointers, this allows the GC to run before it is all cleared.
-func memclrNoHeapPointersChunked(size uintptr, x unsafe.Pointer) {
-	v := uintptr(x)
-	// got this from benchmarking. 128k is too small, 512k is too large.
-	const chunkBytes = 256 * 1024
-	vsize := v + size
-	for voff := v; voff < vsize; voff = voff + chunkBytes {
-		if getg().preempt {
-			// may hold locks, e.g., profiling
-			goschedguarded()
-		}
-		// clear min(avail, lump) bytes
-		n := vsize - voff
-		if n > chunkBytes {
-			n = chunkBytes
-		}
-		memclrNoHeapPointers(unsafe.Pointer(voff), n)
-	}
-}
-
-// implementation of new builtin
-// compiler (both frontend and SSA backend) knows the signature
-// of this function
-func newobject(typ *_type) unsafe.Pointer {
-	return mallocgc(typ.size, typ, true)
-}
-
-//go:linkname reflect_unsafe_New reflect.unsafe_New
-func reflect_unsafe_New(typ *_type) unsafe.Pointer {
-	return mallocgc(typ.size, typ, true)
-}
-
-//go:linkname reflectlite_unsafe_New internal/reflectlite.unsafe_New
-func reflectlite_unsafe_New(typ *_type) unsafe.Pointer {
-	return mallocgc(typ.size, typ, true)
-}
-
-// newarray allocates an array of n elements of type typ.
-func newarray(typ *_type, n int) unsafe.Pointer {
-	if n == 1 {
-		return mallocgc(typ.size, typ, true)
-	}
-	mem, overflow := math.MulUintptr(typ.size, uintptr(n))
-	if overflow || mem > maxAlloc || n < 0 {
-		panic(plainError("runtime: allocation size out of range"))
-	}
-	return mallocgc(mem, typ, true)
-}
-
-//go:linkname reflect_unsafe_NewArray reflect.unsafe_NewArray
-func reflect_unsafe_NewArray(typ *_type, n int) unsafe.Pointer {
-	return newarray(typ, n)
-}
-
-func profilealloc(mp *m, x unsafe.Pointer, size uintptr) {
-	c := getMCache(mp)
-	if c == nil {
-		throw("profilealloc called without a P or outside bootstrapping")
-	}
-	c.nextSample = nextSample()
-	mProf_Malloc(x, size)
-}
-
-// nextSample returns the next sampling point for heap profiling. The goal is
-// to sample allocations on average every MemProfileRate bytes, but with a
-// completely random distribution over the allocation timeline; this
-// corresponds to a Poisson process with parameter MemProfileRate. In Poisson
-// processes, the distance between two samples follows the exponential
-// distribution (exp(MemProfileRate)), so the best return value is a random
-// number taken from an exponential distribution whose mean is MemProfileRate.
-func nextSample() uintptr {
-	if MemProfileRate == 1 {
-		// Callers assign our return value to
-		// mcache.next_sample, but next_sample is not used
-		// when the rate is 1. So avoid the math below and
-		// just return something.
-		return 0
-	}
-	if GOOS == "plan9" {
-		// Plan 9 doesn't support floating point in note handler.
-		if g := getg(); g == g.m.gsignal {
-			return nextSampleNoFP()
-		}
-	}
-
-	return uintptr(fastexprand(MemProfileRate))
-}
-
-// fastexprand returns a random number from an exponential distribution with
-// the specified mean.
-func fastexprand(mean int) int32 {
-	// Avoid overflow. Maximum possible step is
-	// -ln(1/(1<<randomBitCount)) * mean, approximately 20 * mean.
-	switch {
-	case mean > 0x7000000:
-		mean = 0x7000000
-	case mean == 0:
-		return 0
-	}
-
-	// Take a random sample of the exponential distribution exp(-mean*x).
-	// The probability distribution function is mean*exp(-mean*x), so the CDF is
-	// p = 1 - exp(-mean*x), so
-	// q = 1 - p == exp(-mean*x)
-	// log_e(q) = -mean*x
-	// -log_e(q)/mean = x
-	// x = -log_e(q) * mean
-	// x = log_2(q) * (-log_e(2)) * mean    ; Using log_2 for efficiency
-	const randomBitCount = 26
-	q := fastrandn(1<<randomBitCount) + 1
-	qlog := fastlog2(float64(q)) - randomBitCount
-	if qlog > 0 {
-		qlog = 0
-	}
-	const minusLog2 = -0.6931471805599453 // -ln(2)
-	return int32(qlog*(minusLog2*float64(mean))) + 1
-}
-
-// nextSampleNoFP is similar to nextSample, but uses older,
-// simpler code to avoid floating point.
-func nextSampleNoFP() uintptr {
-	// Set first allocation sample size.
-	rate := MemProfileRate
-	if rate > 0x3fffffff { // make 2*rate not overflow
-		rate = 0x3fffffff
-	}
-	if rate != 0 {
-		return uintptr(fastrandn(uint32(2 * rate)))
-	}
-	return 0
-}
-
-type persistentAlloc struct {
-	base *notInHeap
-	off  uintptr
-}
-
-var globalAlloc struct {
-	mutex
-	persistentAlloc
-}
-
-// persistentChunkSize is the number of bytes we allocate when we grow
-// a persistentAlloc.
-const persistentChunkSize = 256 << 10
-
-// persistentChunks is a list of all the persistent chunks we have
-// allocated. The list is maintained through the first word in the
-// persistent chunk. This is updated atomically.
-var persistentChunks *notInHeap
-
-// Wrapper around sysAlloc that can allocate small chunks.
-// There is no associated free operation.
-// Intended for things like function/type/debug-related persistent data.
-// If align is 0, uses default align (currently 8).
-// The returned memory will be zeroed.
-//
-// Consider marking persistentalloc'd types go:notinheap.
-func persistentalloc(size, align uintptr, sysStat *sysMemStat) unsafe.Pointer {
-	var p *notInHeap
-	systemstack(func() {
-		p = persistentalloc1(size, align, sysStat)
-	})
-	return unsafe.Pointer(p)
-}
-
-// Must run on system stack because stack growth can (re)invoke it.
-// See issue 9174.
-//go:systemstack
-func persistentalloc1(size, align uintptr, sysStat *sysMemStat) *notInHeap {
-	const (
-		maxBlock = 64 << 10 // VM reservation granularity is 64K on windows
-	)
-
-	if size == 0 {
-		throw("persistentalloc: size == 0")
-	}
-	if align != 0 {
-		if align&(align-1) != 0 {
-			throw("persistentalloc: align is not a power of 2")
-		}
-		if align > _PageSize {
-			throw("persistentalloc: align is too large")
-		}
-	} else {
-		align = 8
-	}
-
-	if size >= maxBlock {
-		return (*notInHeap)(sysAlloc(size, sysStat))
-	}
-
-	mp := acquirem()
-	var persistent *persistentAlloc
-	if mp != nil && mp.p != 0 {
-		persistent = &mp.p.ptr().palloc
-	} else {
-		lock(&globalAlloc.mutex)
-		persistent = &globalAlloc.persistentAlloc
-	}
-	persistent.off = alignUp(persistent.off, align)
-	if persistent.off+size > persistentChunkSize || persistent.base == nil {
-		persistent.base = (*notInHeap)(sysAlloc(persistentChunkSize, &memstats.other_sys))
-		if persistent.base == nil {
-			if persistent == &globalAlloc.persistentAlloc {
-				unlock(&globalAlloc.mutex)
-			}
-			throw("runtime: cannot allocate memory")
-		}
-
-		// Add the new chunk to the persistentChunks list.
-		for {
-			chunks := uintptr(unsafe.Pointer(persistentChunks))
-			*(*uintptr)(unsafe.Pointer(persistent.base)) = chunks
-			if atomic.Casuintptr((*uintptr)(unsafe.Pointer(&persistentChunks)), chunks, uintptr(unsafe.Pointer(persistent.base))) {
-				break
-			}
-		}
-		persistent.off = alignUp(goarch.PtrSize, align)
-	}
-	p := persistent.base.add(persistent.off)
-	persistent.off += size
-	releasem(mp)
-	if persistent == &globalAlloc.persistentAlloc {
-		unlock(&globalAlloc.mutex)
-	}
-
-	if sysStat != &memstats.other_sys {
-		sysStat.add(int64(size))
-		memstats.other_sys.add(-int64(size))
-	}
-	return p
-}
-
-// inPersistentAlloc reports whether p points to memory allocated by
-// persistentalloc. This must be nosplit because it is called by the
-// cgo checker code, which is called by the write barrier code.
-//go:nosplit
-func inPersistentAlloc(p uintptr) bool {
-	chunk := atomic.Loaduintptr((*uintptr)(unsafe.Pointer(&persistentChunks)))
-	for chunk != 0 {
-		if p >= chunk && p < chunk+persistentChunkSize {
-			return true
-		}
-		chunk = *(*uintptr)(unsafe.Pointer(chunk))
-	}
-	return false
-}
-
-// linearAlloc is a simple linear allocator that pre-reserves a region
-// of memory and then optionally maps that region into the Ready state
-// as needed.
-//
-// The caller is responsible for locking.
-type linearAlloc struct {
-	next   uintptr // next free byte
-	mapped uintptr // one byte past end of mapped space
-	end    uintptr // end of reserved space
-
-	mapMemory bool // transition memory from Reserved to Ready if true
-}
-
-func (l *linearAlloc) init(base, size uintptr, mapMemory bool) {
-	if base+size < base {
-		// Chop off the last byte. The runtime isn't prepared
-		// to deal with situations where the bounds could overflow.
-		// Leave that memory reserved, though, so we don't map it
-		// later.
-		size -= 1
-	}
-	l.next, l.mapped = base, base
-	l.end = base + size
-	l.mapMemory = mapMemory
-}
-
-func (l *linearAlloc) alloc(size, align uintptr, sysStat *sysMemStat) unsafe.Pointer {
-	p := alignUp(l.next, align)
-	if p+size > l.end {
-		return nil
-	}
-	l.next = p + size
-	if pEnd := alignUp(l.next-1, physPageSize); pEnd > l.mapped {
-		if l.mapMemory {
-			// Transition from Reserved to Prepared to Ready.
-			sysMap(unsafe.Pointer(l.mapped), pEnd-l.mapped, sysStat)
-			sysUsed(unsafe.Pointer(l.mapped), pEnd-l.mapped)
-		}
-		l.mapped = pEnd
-	}
-	return unsafe.Pointer(p)
-}
-
-// notInHeap is off-heap memory allocated by a lower-level allocator
-// like sysAlloc or persistentAlloc.
-//
-// In general, it's better to use real types marked as go:notinheap,
-// but this serves as a generic type for situations where that isn't
-// possible (like in the allocators).
-//
-// TODO: Use this as the return type of sysAlloc, persistentAlloc, etc?
-//
-//go:notinheap
-type notInHeap struct{}
-
-func (p *notInHeap) add(bytes uintptr) *notInHeap {
-	return (*notInHeap)(unsafe.Pointer(uintptr(unsafe.Pointer(p)) + bytes))
-}
-
-// computeRZlog computes the size of the redzone.
-// Refer to the implementation of the compiler-rt.
-func computeRZlog(userSize uintptr) uintptr {
-	switch {
-	case userSize <= (64 - 16):
-		return 16 << 0
-	case userSize <= (128 - 32):
-		return 16 << 1
-	case userSize <= (512 - 64):
-		return 16 << 2
-	case userSize <= (4096 - 128):
-		return 16 << 3
-	case userSize <= (1<<14)-256:
-		return 16 << 4
-	case userSize <= (1<<15)-512:
-		return 16 << 5
-	case userSize <= (1<<16)-1024:
-		return 16 << 6
-	default:
-		return 16 << 7
-	}
-}
diff --git a/contrib/go/_std_1.18/src/runtime/map.go b/contrib/go/_std_1.18/src/runtime/map.go
deleted file mode 100644
index e91b25eaec..0000000000
--- a/contrib/go/_std_1.18/src/runtime/map.go
+++ /dev/null
@@ -1,1416 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-// This file contains the implementation of Go's map type.
-//
-// A map is just a hash table. The data is arranged
-// into an array of buckets. Each bucket contains up to
-// 8 key/elem pairs. The low-order bits of the hash are
-// used to select a bucket. Each bucket contains a few
-// high-order bits of each hash to distinguish the entries
-// within a single bucket.
-//
-// If more than 8 keys hash to a bucket, we chain on
-// extra buckets.
-//
-// When the hashtable grows, we allocate a new array
-// of buckets twice as big. Buckets are incrementally
-// copied from the old bucket array to the new bucket array.
-//
-// Map iterators walk through the array of buckets and
-// return the keys in walk order (bucket #, then overflow
-// chain order, then bucket index).  To maintain iteration
-// semantics, we never move keys within their bucket (if
-// we did, keys might be returned 0 or 2 times).  When
-// growing the table, iterators remain iterating through the
-// old table and must check the new table if the bucket
-// they are iterating through has been moved ("evacuated")
-// to the new table.
-
-// Picking loadFactor: too large and we have lots of overflow
-// buckets, too small and we waste a lot of space. I wrote
-// a simple program to check some stats for different loads:
-// (64-bit, 8 byte keys and elems)
-//  loadFactor    %overflow  bytes/entry     hitprobe    missprobe
-//        4.00         2.13        20.77         3.00         4.00
-//        4.50         4.05        17.30         3.25         4.50
-//        5.00         6.85        14.77         3.50         5.00
-//        5.50        10.55        12.94         3.75         5.50
-//        6.00        15.27        11.67         4.00         6.00
-//        6.50        20.90        10.79         4.25         6.50
-//        7.00        27.14        10.15         4.50         7.00
-//        7.50        34.03         9.73         4.75         7.50
-//        8.00        41.10         9.40         5.00         8.00
-//
-// %overflow   = percentage of buckets which have an overflow bucket
-// bytes/entry = overhead bytes used per key/elem pair
-// hitprobe    = # of entries to check when looking up a present key
-// missprobe   = # of entries to check when looking up an absent key
-//
-// Keep in mind this data is for maximally loaded tables, i.e. just
-// before the table grows. Typical tables will be somewhat less loaded.
-
-import (
-	"internal/abi"
-	"internal/goarch"
-	"runtime/internal/atomic"
-	"runtime/internal/math"
-	"unsafe"
-)
-
-const (
-	// Maximum number of key/elem pairs a bucket can hold.
-	bucketCntBits = 3
-	bucketCnt     = 1 << bucketCntBits
-
-	// Maximum average load of a bucket that triggers growth is 6.5.
-	// Represent as loadFactorNum/loadFactorDen, to allow integer math.
-	loadFactorNum = 13
-	loadFactorDen = 2
-
-	// Maximum key or elem size to keep inline (instead of mallocing per element).
-	// Must fit in a uint8.
-	// Fast versions cannot handle big elems - the cutoff size for
-	// fast versions in cmd/compile/internal/gc/walk.go must be at most this elem.
-	maxKeySize  = 128
-	maxElemSize = 128
-
-	// data offset should be the size of the bmap struct, but needs to be
-	// aligned correctly. For amd64p32 this means 64-bit alignment
-	// even though pointers are 32 bit.
-	dataOffset = unsafe.Offsetof(struct {
-		b bmap
-		v int64
-	}{}.v)
-
-	// Possible tophash values. We reserve a few possibilities for special marks.
-	// Each bucket (including its overflow buckets, if any) will have either all or none of its
-	// entries in the evacuated* states (except during the evacuate() method, which only happens
-	// during map writes and thus no one else can observe the map during that time).
-	emptyRest      = 0 // this cell is empty, and there are no more non-empty cells at higher indexes or overflows.
-	emptyOne       = 1 // this cell is empty
-	evacuatedX     = 2 // key/elem is valid.  Entry has been evacuated to first half of larger table.
-	evacuatedY     = 3 // same as above, but evacuated to second half of larger table.
-	evacuatedEmpty = 4 // cell is empty, bucket is evacuated.
-	minTopHash     = 5 // minimum tophash for a normal filled cell.
-
-	// flags
-	iterator     = 1 // there may be an iterator using buckets
-	oldIterator  = 2 // there may be an iterator using oldbuckets
-	hashWriting  = 4 // a goroutine is writing to the map
-	sameSizeGrow = 8 // the current map growth is to a new map of the same size
-
-	// sentinel bucket ID for iterator checks
-	noCheck = 1<<(8*goarch.PtrSize) - 1
-)
-
-// isEmpty reports whether the given tophash array entry represents an empty bucket entry.
-func isEmpty(x uint8) bool {
-	return x <= emptyOne
-}
-
-// A header for a Go map.
-type hmap struct {
-	// Note: the format of the hmap is also encoded in cmd/compile/internal/reflectdata/reflect.go.
-	// Make sure this stays in sync with the compiler's definition.
-	count     int // # live cells == size of map.  Must be first (used by len() builtin)
-	flags     uint8
-	B         uint8  // log_2 of # of buckets (can hold up to loadFactor * 2^B items)
-	noverflow uint16 // approximate number of overflow buckets; see incrnoverflow for details
-	hash0     uint32 // hash seed
-
-	buckets    unsafe.Pointer // array of 2^B Buckets. may be nil if count==0.
-	oldbuckets unsafe.Pointer // previous bucket array of half the size, non-nil only when growing
-	nevacuate  uintptr        // progress counter for evacuation (buckets less than this have been evacuated)
-
-	extra *mapextra // optional fields
-}
-
-// mapextra holds fields that are not present on all maps.
-type mapextra struct {
-	// If both key and elem do not contain pointers and are inline, then we mark bucket
-	// type as containing no pointers. This avoids scanning such maps.
-	// However, bmap.overflow is a pointer. In order to keep overflow buckets
-	// alive, we store pointers to all overflow buckets in hmap.extra.overflow and hmap.extra.oldoverflow.
-	// overflow and oldoverflow are only used if key and elem do not contain pointers.
-	// overflow contains overflow buckets for hmap.buckets.
-	// oldoverflow contains overflow buckets for hmap.oldbuckets.
-	// The indirection allows to store a pointer to the slice in hiter.
-	overflow    *[]*bmap
-	oldoverflow *[]*bmap
-
-	// nextOverflow holds a pointer to a free overflow bucket.
-	nextOverflow *bmap
-}
-
-// A bucket for a Go map.
-type bmap struct {
-	// tophash generally contains the top byte of the hash value
-	// for each key in this bucket. If tophash[0] < minTopHash,
-	// tophash[0] is a bucket evacuation state instead.
-	tophash [bucketCnt]uint8
-	// Followed by bucketCnt keys and then bucketCnt elems.
-	// NOTE: packing all the keys together and then all the elems together makes the
-	// code a bit more complicated than alternating key/elem/key/elem/... but it allows
-	// us to eliminate padding which would be needed for, e.g., map[int64]int8.
-	// Followed by an overflow pointer.
-}
-
-// A hash iteration structure.
-// If you modify hiter, also change cmd/compile/internal/reflectdata/reflect.go
-// and reflect/value.go to match the layout of this structure.
-type hiter struct {
-	key         unsafe.Pointer // Must be in first position.  Write nil to indicate iteration end (see cmd/compile/internal/walk/range.go).
-	elem        unsafe.Pointer // Must be in second position (see cmd/compile/internal/walk/range.go).
-	t           *maptype
-	h           *hmap
-	buckets     unsafe.Pointer // bucket ptr at hash_iter initialization time
-	bptr        *bmap          // current bucket
-	overflow    *[]*bmap       // keeps overflow buckets of hmap.buckets alive
-	oldoverflow *[]*bmap       // keeps overflow buckets of hmap.oldbuckets alive
-	startBucket uintptr        // bucket iteration started at
-	offset      uint8          // intra-bucket offset to start from during iteration (should be big enough to hold bucketCnt-1)
-	wrapped     bool           // already wrapped around from end of bucket array to beginning
-	B           uint8
-	i           uint8
-	bucket      uintptr
-	checkBucket uintptr
-}
-
-// bucketShift returns 1<<b, optimized for code generation.
-func bucketShift(b uint8) uintptr {
-	// Masking the shift amount allows overflow checks to be elided.
-	return uintptr(1) << (b & (goarch.PtrSize*8 - 1))
-}
-
-// bucketMask returns 1<<b - 1, optimized for code generation.
-func bucketMask(b uint8) uintptr {
-	return bucketShift(b) - 1
-}
-
-// tophash calculates the tophash value for hash.
-func tophash(hash uintptr) uint8 {
-	top := uint8(hash >> (goarch.PtrSize*8 - 8))
-	if top < minTopHash {
-		top += minTopHash
-	}
-	return top
-}
-
-func evacuated(b *bmap) bool {
-	h := b.tophash[0]
-	return h > emptyOne && h < minTopHash
-}
-
-func (b *bmap) overflow(t *maptype) *bmap {
-	return *(**bmap)(add(unsafe.Pointer(b), uintptr(t.bucketsize)-goarch.PtrSize))
-}
-
-func (b *bmap) setoverflow(t *maptype, ovf *bmap) {
-	*(**bmap)(add(unsafe.Pointer(b), uintptr(t.bucketsize)-goarch.PtrSize)) = ovf
-}
-
-func (b *bmap) keys() unsafe.Pointer {
-	return add(unsafe.Pointer(b), dataOffset)
-}
-
-// incrnoverflow increments h.noverflow.
-// noverflow counts the number of overflow buckets.
-// This is used to trigger same-size map growth.
-// See also tooManyOverflowBuckets.
-// To keep hmap small, noverflow is a uint16.
-// When there are few buckets, noverflow is an exact count.
-// When there are many buckets, noverflow is an approximate count.
-func (h *hmap) incrnoverflow() {
-	// We trigger same-size map growth if there are
-	// as many overflow buckets as buckets.
-	// We need to be able to count to 1<<h.B.
-	if h.B < 16 {
-		h.noverflow++
-		return
-	}
-	// Increment with probability 1/(1<<(h.B-15)).
-	// When we reach 1<<15 - 1, we will have approximately
-	// as many overflow buckets as buckets.
-	mask := uint32(1)<<(h.B-15) - 1
-	// Example: if h.B == 18, then mask == 7,
-	// and fastrand & 7 == 0 with probability 1/8.
-	if fastrand()&mask == 0 {
-		h.noverflow++
-	}
-}
-
-func (h *hmap) newoverflow(t *maptype, b *bmap) *bmap {
-	var ovf *bmap
-	if h.extra != nil && h.extra.nextOverflow != nil {
-		// We have preallocated overflow buckets available.
-		// See makeBucketArray for more details.
-		ovf = h.extra.nextOverflow
-		if ovf.overflow(t) == nil {
-			// We're not at the end of the preallocated overflow buckets. Bump the pointer.
-			h.extra.nextOverflow = (*bmap)(add(unsafe.Pointer(ovf), uintptr(t.bucketsize)))
-		} else {
-			// This is the last preallocated overflow bucket.
-			// Reset the overflow pointer on this bucket,
-			// which was set to a non-nil sentinel value.
-			ovf.setoverflow(t, nil)
-			h.extra.nextOverflow = nil
-		}
-	} else {
-		ovf = (*bmap)(newobject(t.bucket))
-	}
-	h.incrnoverflow()
-	if t.bucket.ptrdata == 0 {
-		h.createOverflow()
-		*h.extra.overflow = append(*h.extra.overflow, ovf)
-	}
-	b.setoverflow(t, ovf)
-	return ovf
-}
-
-func (h *hmap) createOverflow() {
-	if h.extra == nil {
-		h.extra = new(mapextra)
-	}
-	if h.extra.overflow == nil {
-		h.extra.overflow = new([]*bmap)
-	}
-}
-
-func makemap64(t *maptype, hint int64, h *hmap) *hmap {
-	if int64(int(hint)) != hint {
-		hint = 0
-	}
-	return makemap(t, int(hint), h)
-}
-
-// makemap_small implements Go map creation for make(map[k]v) and
-// make(map[k]v, hint) when hint is known to be at most bucketCnt
-// at compile time and the map needs to be allocated on the heap.
-func makemap_small() *hmap {
-	h := new(hmap)
-	h.hash0 = fastrand()
-	return h
-}
-
-// makemap implements Go map creation for make(map[k]v, hint).
-// If the compiler has determined that the map or the first bucket
-// can be created on the stack, h and/or bucket may be non-nil.
-// If h != nil, the map can be created directly in h.
-// If h.buckets != nil, bucket pointed to can be used as the first bucket.
-func makemap(t *maptype, hint int, h *hmap) *hmap {
-	mem, overflow := math.MulUintptr(uintptr(hint), t.bucket.size)
-	if overflow || mem > maxAlloc {
-		hint = 0
-	}
-
-	// initialize Hmap
-	if h == nil {
-		h = new(hmap)
-	}
-	h.hash0 = fastrand()
-
-	// Find the size parameter B which will hold the requested # of elements.
-	// For hint < 0 overLoadFactor returns false since hint < bucketCnt.
-	B := uint8(0)
-	for overLoadFactor(hint, B) {
-		B++
-	}
-	h.B = B
-
-	// allocate initial hash table
-	// if B == 0, the buckets field is allocated lazily later (in mapassign)
-	// If hint is large zeroing this memory could take a while.
-	if h.B != 0 {
-		var nextOverflow *bmap
-		h.buckets, nextOverflow = makeBucketArray(t, h.B, nil)
-		if nextOverflow != nil {
-			h.extra = new(mapextra)
-			h.extra.nextOverflow = nextOverflow
-		}
-	}
-
-	return h
-}
-
-// makeBucketArray initializes a backing array for map buckets.
-// 1<<b is the minimum number of buckets to allocate.
-// dirtyalloc should either be nil or a bucket array previously
-// allocated by makeBucketArray with the same t and b parameters.
-// If dirtyalloc is nil a new backing array will be alloced and
-// otherwise dirtyalloc will be cleared and reused as backing array.
-func makeBucketArray(t *maptype, b uint8, dirtyalloc unsafe.Pointer) (buckets unsafe.Pointer, nextOverflow *bmap) {
-	base := bucketShift(b)
-	nbuckets := base
-	// For small b, overflow buckets are unlikely.
-	// Avoid the overhead of the calculation.
-	if b >= 4 {
-		// Add on the estimated number of overflow buckets
-		// required to insert the median number of elements
-		// used with this value of b.
-		nbuckets += bucketShift(b - 4)
-		sz := t.bucket.size * nbuckets
-		up := roundupsize(sz)
-		if up != sz {
-			nbuckets = up / t.bucket.size
-		}
-	}
-
-	if dirtyalloc == nil {
-		buckets = newarray(t.bucket, int(nbuckets))
-	} else {
-		// dirtyalloc was previously generated by
-		// the above newarray(t.bucket, int(nbuckets))
-		// but may not be empty.
-		buckets = dirtyalloc
-		size := t.bucket.size * nbuckets
-		if t.bucket.ptrdata != 0 {
-			memclrHasPointers(buckets, size)
-		} else {
-			memclrNoHeapPointers(buckets, size)
-		}
-	}
-
-	if base != nbuckets {
-		// We preallocated some overflow buckets.
-		// To keep the overhead of tracking these overflow buckets to a minimum,
-		// we use the convention that if a preallocated overflow bucket's overflow
-		// pointer is nil, then there are more available by bumping the pointer.
-		// We need a safe non-nil pointer for the last overflow bucket; just use buckets.
-		nextOverflow = (*bmap)(add(buckets, base*uintptr(t.bucketsize)))
-		last := (*bmap)(add(buckets, (nbuckets-1)*uintptr(t.bucketsize)))
-		last.setoverflow(t, (*bmap)(buckets))
-	}
-	return buckets, nextOverflow
-}
-
-// mapaccess1 returns a pointer to h[key].  Never returns nil, instead
-// it will return a reference to the zero object for the elem type if
-// the key is not in the map.
-// NOTE: The returned pointer may keep the whole map live, so don't
-// hold onto it for very long.
-func mapaccess1(t *maptype, h *hmap, key unsafe.Pointer) unsafe.Pointer {
-	if raceenabled && h != nil {
-		callerpc := getcallerpc()
-		pc := abi.FuncPCABIInternal(mapaccess1)
-		racereadpc(unsafe.Pointer(h), callerpc, pc)
-		raceReadObjectPC(t.key, key, callerpc, pc)
-	}
-	if msanenabled && h != nil {
-		msanread(key, t.key.size)
-	}
-	if asanenabled && h != nil {
-		asanread(key, t.key.size)
-	}
-	if h == nil || h.count == 0 {
-		if t.hashMightPanic() {
-			t.hasher(key, 0) // see issue 23734
-		}
-		return unsafe.Pointer(&zeroVal[0])
-	}
-	if h.flags&hashWriting != 0 {
-		throw("concurrent map read and map write")
-	}
-	hash := t.hasher(key, uintptr(h.hash0))
-	m := bucketMask(h.B)
-	b := (*bmap)(add(h.buckets, (hash&m)*uintptr(t.bucketsize)))
-	if c := h.oldbuckets; c != nil {
-		if !h.sameSizeGrow() {
-			// There used to be half as many buckets; mask down one more power of two.
-			m >>= 1
-		}
-		oldb := (*bmap)(add(c, (hash&m)*uintptr(t.bucketsize)))
-		if !evacuated(oldb) {
-			b = oldb
-		}
-	}
-	top := tophash(hash)
-bucketloop:
-	for ; b != nil; b = b.overflow(t) {
-		for i := uintptr(0); i < bucketCnt; i++ {
-			if b.tophash[i] != top {
-				if b.tophash[i] == emptyRest {
-					break bucketloop
-				}
-				continue
-			}
-			k := add(unsafe.Pointer(b), dataOffset+i*uintptr(t.keysize))
-			if t.indirectkey() {
-				k = *((*unsafe.Pointer)(k))
-			}
-			if t.key.equal(key, k) {
-				e := add(unsafe.Pointer(b), dataOffset+bucketCnt*uintptr(t.keysize)+i*uintptr(t.elemsize))
-				if t.indirectelem() {
-					e = *((*unsafe.Pointer)(e))
-				}
-				return e
-			}
-		}
-	}
-	return unsafe.Pointer(&zeroVal[0])
-}
-
-func mapaccess2(t *maptype, h *hmap, key unsafe.Pointer) (unsafe.Pointer, bool) {
-	if raceenabled && h != nil {
-		callerpc := getcallerpc()
-		pc := abi.FuncPCABIInternal(mapaccess2)
-		racereadpc(unsafe.Pointer(h), callerpc, pc)
-		raceReadObjectPC(t.key, key, callerpc, pc)
-	}
-	if msanenabled && h != nil {
-		msanread(key, t.key.size)
-	}
-	if asanenabled && h != nil {
-		asanread(key, t.key.size)
-	}
-	if h == nil || h.count == 0 {
-		if t.hashMightPanic() {
-			t.hasher(key, 0) // see issue 23734
-		}
-		return unsafe.Pointer(&zeroVal[0]), false
-	}
-	if h.flags&hashWriting != 0 {
-		throw("concurrent map read and map write")
-	}
-	hash := t.hasher(key, uintptr(h.hash0))
-	m := bucketMask(h.B)
-	b := (*bmap)(add(h.buckets, (hash&m)*uintptr(t.bucketsize)))
-	if c := h.oldbuckets; c != nil {
-		if !h.sameSizeGrow() {
-			// There used to be half as many buckets; mask down one more power of two.
-			m >>= 1
-		}
-		oldb := (*bmap)(add(c, (hash&m)*uintptr(t.bucketsize)))
-		if !evacuated(oldb) {
-			b = oldb
-		}
-	}
-	top := tophash(hash)
-bucketloop:
-	for ; b != nil; b = b.overflow(t) {
-		for i := uintptr(0); i < bucketCnt; i++ {
-			if b.tophash[i] != top {
-				if b.tophash[i] == emptyRest {
-					break bucketloop
-				}
-				continue
-			}
-			k := add(unsafe.Pointer(b), dataOffset+i*uintptr(t.keysize))
-			if t.indirectkey() {
-				k = *((*unsafe.Pointer)(k))
-			}
-			if t.key.equal(key, k) {
-				e := add(unsafe.Pointer(b), dataOffset+bucketCnt*uintptr(t.keysize)+i*uintptr(t.elemsize))
-				if t.indirectelem() {
-					e = *((*unsafe.Pointer)(e))
-				}
-				return e, true
-			}
-		}
-	}
-	return unsafe.Pointer(&zeroVal[0]), false
-}
-
-// returns both key and elem. Used by map iterator
-func mapaccessK(t *maptype, h *hmap, key unsafe.Pointer) (unsafe.Pointer, unsafe.Pointer) {
-	if h == nil || h.count == 0 {
-		return nil, nil
-	}
-	hash := t.hasher(key, uintptr(h.hash0))
-	m := bucketMask(h.B)
-	b := (*bmap)(add(h.buckets, (hash&m)*uintptr(t.bucketsize)))
-	if c := h.oldbuckets; c != nil {
-		if !h.sameSizeGrow() {
-			// There used to be half as many buckets; mask down one more power of two.
-			m >>= 1
-		}
-		oldb := (*bmap)(add(c, (hash&m)*uintptr(t.bucketsize)))
-		if !evacuated(oldb) {
-			b = oldb
-		}
-	}
-	top := tophash(hash)
-bucketloop:
-	for ; b != nil; b = b.overflow(t) {
-		for i := uintptr(0); i < bucketCnt; i++ {
-			if b.tophash[i] != top {
-				if b.tophash[i] == emptyRest {
-					break bucketloop
-				}
-				continue
-			}
-			k := add(unsafe.Pointer(b), dataOffset+i*uintptr(t.keysize))
-			if t.indirectkey() {
-				k = *((*unsafe.Pointer)(k))
-			}
-			if t.key.equal(key, k) {
-				e := add(unsafe.Pointer(b), dataOffset+bucketCnt*uintptr(t.keysize)+i*uintptr(t.elemsize))
-				if t.indirectelem() {
-					e = *((*unsafe.Pointer)(e))
-				}
-				return k, e
-			}
-		}
-	}
-	return nil, nil
-}
-
-func mapaccess1_fat(t *maptype, h *hmap, key, zero unsafe.Pointer) unsafe.Pointer {
-	e := mapaccess1(t, h, key)
-	if e == unsafe.Pointer(&zeroVal[0]) {
-		return zero
-	}
-	return e
-}
-
-func mapaccess2_fat(t *maptype, h *hmap, key, zero unsafe.Pointer) (unsafe.Pointer, bool) {
-	e := mapaccess1(t, h, key)
-	if e == unsafe.Pointer(&zeroVal[0]) {
-		return zero, false
-	}
-	return e, true
-}
-
-// Like mapaccess, but allocates a slot for the key if it is not present in the map.
-func mapassign(t *maptype, h *hmap, key unsafe.Pointer) unsafe.Pointer {
-	if h == nil {
-		panic(plainError("assignment to entry in nil map"))
-	}
-	if raceenabled {
-		callerpc := getcallerpc()
-		pc := abi.FuncPCABIInternal(mapassign)
-		racewritepc(unsafe.Pointer(h), callerpc, pc)
-		raceReadObjectPC(t.key, key, callerpc, pc)
-	}
-	if msanenabled {
-		msanread(key, t.key.size)
-	}
-	if asanenabled {
-		asanread(key, t.key.size)
-	}
-	if h.flags&hashWriting != 0 {
-		throw("concurrent map writes")
-	}
-	hash := t.hasher(key, uintptr(h.hash0))
-
-	// Set hashWriting after calling t.hasher, since t.hasher may panic,
-	// in which case we have not actually done a write.
-	h.flags ^= hashWriting
-
-	if h.buckets == nil {
-		h.buckets = newobject(t.bucket) // newarray(t.bucket, 1)
-	}
-
-again:
-	bucket := hash & bucketMask(h.B)
-	if h.growing() {
-		growWork(t, h, bucket)
-	}
-	b := (*bmap)(add(h.buckets, bucket*uintptr(t.bucketsize)))
-	top := tophash(hash)
-
-	var inserti *uint8
-	var insertk unsafe.Pointer
-	var elem unsafe.Pointer
-bucketloop:
-	for {
-		for i := uintptr(0); i < bucketCnt; i++ {
-			if b.tophash[i] != top {
-				if isEmpty(b.tophash[i]) && inserti == nil {
-					inserti = &b.tophash[i]
-					insertk = add(unsafe.Pointer(b), dataOffset+i*uintptr(t.keysize))
-					elem = add(unsafe.Pointer(b), dataOffset+bucketCnt*uintptr(t.keysize)+i*uintptr(t.elemsize))
-				}
-				if b.tophash[i] == emptyRest {
-					break bucketloop
-				}
-				continue
-			}
-			k := add(unsafe.Pointer(b), dataOffset+i*uintptr(t.keysize))
-			if t.indirectkey() {
-				k = *((*unsafe.Pointer)(k))
-			}
-			if !t.key.equal(key, k) {
-				continue
-			}
-			// already have a mapping for key. Update it.
-			if t.needkeyupdate() {
-				typedmemmove(t.key, k, key)
-			}
-			elem = add(unsafe.Pointer(b), dataOffset+bucketCnt*uintptr(t.keysize)+i*uintptr(t.elemsize))
-			goto done
-		}
-		ovf := b.overflow(t)
-		if ovf == nil {
-			break
-		}
-		b = ovf
-	}
-
-	// Did not find mapping for key. Allocate new cell & add entry.
-
-	// If we hit the max load factor or we have too many overflow buckets,
-	// and we're not already in the middle of growing, start growing.
-	if !h.growing() && (overLoadFactor(h.count+1, h.B) || tooManyOverflowBuckets(h.noverflow, h.B)) {
-		hashGrow(t, h)
-		goto again // Growing the table invalidates everything, so try again
-	}
-
-	if inserti == nil {
-		// The current bucket and all the overflow buckets connected to it are full, allocate a new one.
-		newb := h.newoverflow(t, b)
-		inserti = &newb.tophash[0]
-		insertk = add(unsafe.Pointer(newb), dataOffset)
-		elem = add(insertk, bucketCnt*uintptr(t.keysize))
-	}
-
-	// store new key/elem at insert position
-	if t.indirectkey() {
-		kmem := newobject(t.key)
-		*(*unsafe.Pointer)(insertk) = kmem
-		insertk = kmem
-	}
-	if t.indirectelem() {
-		vmem := newobject(t.elem)
-		*(*unsafe.Pointer)(elem) = vmem
-	}
-	typedmemmove(t.key, insertk, key)
-	*inserti = top
-	h.count++
-
-done:
-	if h.flags&hashWriting == 0 {
-		throw("concurrent map writes")
-	}
-	h.flags &^= hashWriting
-	if t.indirectelem() {
-		elem = *((*unsafe.Pointer)(elem))
-	}
-	return elem
-}
-
-func mapdelete(t *maptype, h *hmap, key unsafe.Pointer) {
-	if raceenabled && h != nil {
-		callerpc := getcallerpc()
-		pc := abi.FuncPCABIInternal(mapdelete)
-		racewritepc(unsafe.Pointer(h), callerpc, pc)
-		raceReadObjectPC(t.key, key, callerpc, pc)
-	}
-	if msanenabled && h != nil {
-		msanread(key, t.key.size)
-	}
-	if asanenabled && h != nil {
-		asanread(key, t.key.size)
-	}
-	if h == nil || h.count == 0 {
-		if t.hashMightPanic() {
-			t.hasher(key, 0) // see issue 23734
-		}
-		return
-	}
-	if h.flags&hashWriting != 0 {
-		throw("concurrent map writes")
-	}
-
-	hash := t.hasher(key, uintptr(h.hash0))
-
-	// Set hashWriting after calling t.hasher, since t.hasher may panic,
-	// in which case we have not actually done a write (delete).
-	h.flags ^= hashWriting
-
-	bucket := hash & bucketMask(h.B)
-	if h.growing() {
-		growWork(t, h, bucket)
-	}
-	b := (*bmap)(add(h.buckets, bucket*uintptr(t.bucketsize)))
-	bOrig := b
-	top := tophash(hash)
-search:
-	for ; b != nil; b = b.overflow(t) {
-		for i := uintptr(0); i < bucketCnt; i++ {
-			if b.tophash[i] != top {
-				if b.tophash[i] == emptyRest {
-					break search
-				}
-				continue
-			}
-			k := add(unsafe.Pointer(b), dataOffset+i*uintptr(t.keysize))
-			k2 := k
-			if t.indirectkey() {
-				k2 = *((*unsafe.Pointer)(k2))
-			}
-			if !t.key.equal(key, k2) {
-				continue
-			}
-			// Only clear key if there are pointers in it.
-			if t.indirectkey() {
-				*(*unsafe.Pointer)(k) = nil
-			} else if t.key.ptrdata != 0 {
-				memclrHasPointers(k, t.key.size)
-			}
-			e := add(unsafe.Pointer(b), dataOffset+bucketCnt*uintptr(t.keysize)+i*uintptr(t.elemsize))
-			if t.indirectelem() {
-				*(*unsafe.Pointer)(e) = nil
-			} else if t.elem.ptrdata != 0 {
-				memclrHasPointers(e, t.elem.size)
-			} else {
-				memclrNoHeapPointers(e, t.elem.size)
-			}
-			b.tophash[i] = emptyOne
-			// If the bucket now ends in a bunch of emptyOne states,
-			// change those to emptyRest states.
-			// It would be nice to make this a separate function, but
-			// for loops are not currently inlineable.
-			if i == bucketCnt-1 {
-				if b.overflow(t) != nil && b.overflow(t).tophash[0] != emptyRest {
-					goto notLast
-				}
-			} else {
-				if b.tophash[i+1] != emptyRest {
-					goto notLast
-				}
-			}
-			for {
-				b.tophash[i] = emptyRest
-				if i == 0 {
-					if b == bOrig {
-						break // beginning of initial bucket, we're done.
-					}
-					// Find previous bucket, continue at its last entry.
-					c := b
-					for b = bOrig; b.overflow(t) != c; b = b.overflow(t) {
-					}
-					i = bucketCnt - 1
-				} else {
-					i--
-				}
-				if b.tophash[i] != emptyOne {
-					break
-				}
-			}
-		notLast:
-			h.count--
-			// Reset the hash seed to make it more difficult for attackers to
-			// repeatedly trigger hash collisions. See issue 25237.
-			if h.count == 0 {
-				h.hash0 = fastrand()
-			}
-			break search
-		}
-	}
-
-	if h.flags&hashWriting == 0 {
-		throw("concurrent map writes")
-	}
-	h.flags &^= hashWriting
-}
-
-// mapiterinit initializes the hiter struct used for ranging over maps.
-// The hiter struct pointed to by 'it' is allocated on the stack
-// by the compilers order pass or on the heap by reflect_mapiterinit.
-// Both need to have zeroed hiter since the struct contains pointers.
-func mapiterinit(t *maptype, h *hmap, it *hiter) {
-	if raceenabled && h != nil {
-		callerpc := getcallerpc()
-		racereadpc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapiterinit))
-	}
-
-	it.t = t
-	if h == nil || h.count == 0 {
-		return
-	}
-
-	if unsafe.Sizeof(hiter{})/goarch.PtrSize != 12 {
-		throw("hash_iter size incorrect") // see cmd/compile/internal/reflectdata/reflect.go
-	}
-	it.h = h
-
-	// grab snapshot of bucket state
-	it.B = h.B
-	it.buckets = h.buckets
-	if t.bucket.ptrdata == 0 {
-		// Allocate the current slice and remember pointers to both current and old.
-		// This preserves all relevant overflow buckets alive even if
-		// the table grows and/or overflow buckets are added to the table
-		// while we are iterating.
-		h.createOverflow()
-		it.overflow = h.extra.overflow
-		it.oldoverflow = h.extra.oldoverflow
-	}
-
-	// decide where to start
-	r := uintptr(fastrand())
-	if h.B > 31-bucketCntBits {
-		r += uintptr(fastrand()) << 31
-	}
-	it.startBucket = r & bucketMask(h.B)
-	it.offset = uint8(r >> h.B & (bucketCnt - 1))
-
-	// iterator state
-	it.bucket = it.startBucket
-
-	// Remember we have an iterator.
-	// Can run concurrently with another mapiterinit().
-	if old := h.flags; old&(iterator|oldIterator) != iterator|oldIterator {
-		atomic.Or8(&h.flags, iterator|oldIterator)
-	}
-
-	mapiternext(it)
-}
-
-func mapiternext(it *hiter) {
-	h := it.h
-	if raceenabled {
-		callerpc := getcallerpc()
-		racereadpc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapiternext))
-	}
-	if h.flags&hashWriting != 0 {
-		throw("concurrent map iteration and map write")
-	}
-	t := it.t
-	bucket := it.bucket
-	b := it.bptr
-	i := it.i
-	checkBucket := it.checkBucket
-
-next:
-	if b == nil {
-		if bucket == it.startBucket && it.wrapped {
-			// end of iteration
-			it.key = nil
-			it.elem = nil
-			return
-		}
-		if h.growing() && it.B == h.B {
-			// Iterator was started in the middle of a grow, and the grow isn't done yet.
-			// If the bucket we're looking at hasn't been filled in yet (i.e. the old
-			// bucket hasn't been evacuated) then we need to iterate through the old
-			// bucket and only return the ones that will be migrated to this bucket.
-			oldbucket := bucket & it.h.oldbucketmask()
-			b = (*bmap)(add(h.oldbuckets, oldbucket*uintptr(t.bucketsize)))
-			if !evacuated(b) {
-				checkBucket = bucket
-			} else {
-				b = (*bmap)(add(it.buckets, bucket*uintptr(t.bucketsize)))
-				checkBucket = noCheck
-			}
-		} else {
-			b = (*bmap)(add(it.buckets, bucket*uintptr(t.bucketsize)))
-			checkBucket = noCheck
-		}
-		bucket++
-		if bucket == bucketShift(it.B) {
-			bucket = 0
-			it.wrapped = true
-		}
-		i = 0
-	}
-	for ; i < bucketCnt; i++ {
-		offi := (i + it.offset) & (bucketCnt - 1)
-		if isEmpty(b.tophash[offi]) || b.tophash[offi] == evacuatedEmpty {
-			// TODO: emptyRest is hard to use here, as we start iterating
-			// in the middle of a bucket. It's feasible, just tricky.
-			continue
-		}
-		k := add(unsafe.Pointer(b), dataOffset+uintptr(offi)*uintptr(t.keysize))
-		if t.indirectkey() {
-			k = *((*unsafe.Pointer)(k))
-		}
-		e := add(unsafe.Pointer(b), dataOffset+bucketCnt*uintptr(t.keysize)+uintptr(offi)*uintptr(t.elemsize))
-		if checkBucket != noCheck && !h.sameSizeGrow() {
-			// Special case: iterator was started during a grow to a larger size
-			// and the grow is not done yet. We're working on a bucket whose
-			// oldbucket has not been evacuated yet. Or at least, it wasn't
-			// evacuated when we started the bucket. So we're iterating
-			// through the oldbucket, skipping any keys that will go
-			// to the other new bucket (each oldbucket expands to two
-			// buckets during a grow).
-			if t.reflexivekey() || t.key.equal(k, k) {
-				// If the item in the oldbucket is not destined for
-				// the current new bucket in the iteration, skip it.
-				hash := t.hasher(k, uintptr(h.hash0))
-				if hash&bucketMask(it.B) != checkBucket {
-					continue
-				}
-			} else {
-				// Hash isn't repeatable if k != k (NaNs).  We need a
-				// repeatable and randomish choice of which direction
-				// to send NaNs during evacuation. We'll use the low
-				// bit of tophash to decide which way NaNs go.
-				// NOTE: this case is why we need two evacuate tophash
-				// values, evacuatedX and evacuatedY, that differ in
-				// their low bit.
-				if checkBucket>>(it.B-1) != uintptr(b.tophash[offi]&1) {
-					continue
-				}
-			}
-		}
-		if (b.tophash[offi] != evacuatedX && b.tophash[offi] != evacuatedY) ||
-			!(t.reflexivekey() || t.key.equal(k, k)) {
-			// This is the golden data, we can return it.
-			// OR
-			// key!=key, so the entry can't be deleted or updated, so we can just return it.
-			// That's lucky for us because when key!=key we can't look it up successfully.
-			it.key = k
-			if t.indirectelem() {
-				e = *((*unsafe.Pointer)(e))
-			}
-			it.elem = e
-		} else {
-			// The hash table has grown since the iterator was started.
-			// The golden data for this key is now somewhere else.
-			// Check the current hash table for the data.
-			// This code handles the case where the key
-			// has been deleted, updated, or deleted and reinserted.
-			// NOTE: we need to regrab the key as it has potentially been
-			// updated to an equal() but not identical key (e.g. +0.0 vs -0.0).
-			rk, re := mapaccessK(t, h, k)
-			if rk == nil {
-				continue // key has been deleted
-			}
-			it.key = rk
-			it.elem = re
-		}
-		it.bucket = bucket
-		if it.bptr != b { // avoid unnecessary write barrier; see issue 14921
-			it.bptr = b
-		}
-		it.i = i + 1
-		it.checkBucket = checkBucket
-		return
-	}
-	b = b.overflow(t)
-	i = 0
-	goto next
-}
-
-// mapclear deletes all keys from a map.
-func mapclear(t *maptype, h *hmap) {
-	if raceenabled && h != nil {
-		callerpc := getcallerpc()
-		pc := abi.FuncPCABIInternal(mapclear)
-		racewritepc(unsafe.Pointer(h), callerpc, pc)
-	}
-
-	if h == nil || h.count == 0 {
-		return
-	}
-
-	if h.flags&hashWriting != 0 {
-		throw("concurrent map writes")
-	}
-
-	h.flags ^= hashWriting
-
-	h.flags &^= sameSizeGrow
-	h.oldbuckets = nil
-	h.nevacuate = 0
-	h.noverflow = 0
-	h.count = 0
-
-	// Reset the hash seed to make it more difficult for attackers to
-	// repeatedly trigger hash collisions. See issue 25237.
-	h.hash0 = fastrand()
-
-	// Keep the mapextra allocation but clear any extra information.
-	if h.extra != nil {
-		*h.extra = mapextra{}
-	}
-
-	// makeBucketArray clears the memory pointed to by h.buckets
-	// and recovers any overflow buckets by generating them
-	// as if h.buckets was newly alloced.
-	_, nextOverflow := makeBucketArray(t, h.B, h.buckets)
-	if nextOverflow != nil {
-		// If overflow buckets are created then h.extra
-		// will have been allocated during initial bucket creation.
-		h.extra.nextOverflow = nextOverflow
-	}
-
-	if h.flags&hashWriting == 0 {
-		throw("concurrent map writes")
-	}
-	h.flags &^= hashWriting
-}
-
-func hashGrow(t *maptype, h *hmap) {
-	// If we've hit the load factor, get bigger.
-	// Otherwise, there are too many overflow buckets,
-	// so keep the same number of buckets and "grow" laterally.
-	bigger := uint8(1)
-	if !overLoadFactor(h.count+1, h.B) {
-		bigger = 0
-		h.flags |= sameSizeGrow
-	}
-	oldbuckets := h.buckets
-	newbuckets, nextOverflow := makeBucketArray(t, h.B+bigger, nil)
-
-	flags := h.flags &^ (iterator | oldIterator)
-	if h.flags&iterator != 0 {
-		flags |= oldIterator
-	}
-	// commit the grow (atomic wrt gc)
-	h.B += bigger
-	h.flags = flags
-	h.oldbuckets = oldbuckets
-	h.buckets = newbuckets
-	h.nevacuate = 0
-	h.noverflow = 0
-
-	if h.extra != nil && h.extra.overflow != nil {
-		// Promote current overflow buckets to the old generation.
-		if h.extra.oldoverflow != nil {
-			throw("oldoverflow is not nil")
-		}
-		h.extra.oldoverflow = h.extra.overflow
-		h.extra.overflow = nil
-	}
-	if nextOverflow != nil {
-		if h.extra == nil {
-			h.extra = new(mapextra)
-		}
-		h.extra.nextOverflow = nextOverflow
-	}
-
-	// the actual copying of the hash table data is done incrementally
-	// by growWork() and evacuate().
-}
-
-// overLoadFactor reports whether count items placed in 1<<B buckets is over loadFactor.
-func overLoadFactor(count int, B uint8) bool {
-	return count > bucketCnt && uintptr(count) > loadFactorNum*(bucketShift(B)/loadFactorDen)
-}
-
-// tooManyOverflowBuckets reports whether noverflow buckets is too many for a map with 1<<B buckets.
-// Note that most of these overflow buckets must be in sparse use;
-// if use was dense, then we'd have already triggered regular map growth.
-func tooManyOverflowBuckets(noverflow uint16, B uint8) bool {
-	// If the threshold is too low, we do extraneous work.
-	// If the threshold is too high, maps that grow and shrink can hold on to lots of unused memory.
-	// "too many" means (approximately) as many overflow buckets as regular buckets.
-	// See incrnoverflow for more details.
-	if B > 15 {
-		B = 15
-	}
-	// The compiler doesn't see here that B < 16; mask B to generate shorter shift code.
-	return noverflow >= uint16(1)<<(B&15)
-}
-
-// growing reports whether h is growing. The growth may be to the same size or bigger.
-func (h *hmap) growing() bool {
-	return h.oldbuckets != nil
-}
-
-// sameSizeGrow reports whether the current growth is to a map of the same size.
-func (h *hmap) sameSizeGrow() bool {
-	return h.flags&sameSizeGrow != 0
-}
-
-// noldbuckets calculates the number of buckets prior to the current map growth.
-func (h *hmap) noldbuckets() uintptr {
-	oldB := h.B
-	if !h.sameSizeGrow() {
-		oldB--
-	}
-	return bucketShift(oldB)
-}
-
-// oldbucketmask provides a mask that can be applied to calculate n % noldbuckets().
-func (h *hmap) oldbucketmask() uintptr {
-	return h.noldbuckets() - 1
-}
-
-func growWork(t *maptype, h *hmap, bucket uintptr) {
-	// make sure we evacuate the oldbucket corresponding
-	// to the bucket we're about to use
-	evacuate(t, h, bucket&h.oldbucketmask())
-
-	// evacuate one more oldbucket to make progress on growing
-	if h.growing() {
-		evacuate(t, h, h.nevacuate)
-	}
-}
-
-func bucketEvacuated(t *maptype, h *hmap, bucket uintptr) bool {
-	b := (*bmap)(add(h.oldbuckets, bucket*uintptr(t.bucketsize)))
-	return evacuated(b)
-}
-
-// evacDst is an evacuation destination.
-type evacDst struct {
-	b *bmap          // current destination bucket
-	i int            // key/elem index into b
-	k unsafe.Pointer // pointer to current key storage
-	e unsafe.Pointer // pointer to current elem storage
-}
-
-func evacuate(t *maptype, h *hmap, oldbucket uintptr) {
-	b := (*bmap)(add(h.oldbuckets, oldbucket*uintptr(t.bucketsize)))
-	newbit := h.noldbuckets()
-	if !evacuated(b) {
-		// TODO: reuse overflow buckets instead of using new ones, if there
-		// is no iterator using the old buckets.  (If !oldIterator.)
-
-		// xy contains the x and y (low and high) evacuation destinations.
-		var xy [2]evacDst
-		x := &xy[0]
-		x.b = (*bmap)(add(h.buckets, oldbucket*uintptr(t.bucketsize)))
-		x.k = add(unsafe.Pointer(x.b), dataOffset)
-		x.e = add(x.k, bucketCnt*uintptr(t.keysize))
-
-		if !h.sameSizeGrow() {
-			// Only calculate y pointers if we're growing bigger.
-			// Otherwise GC can see bad pointers.
-			y := &xy[1]
-			y.b = (*bmap)(add(h.buckets, (oldbucket+newbit)*uintptr(t.bucketsize)))
-			y.k = add(unsafe.Pointer(y.b), dataOffset)
-			y.e = add(y.k, bucketCnt*uintptr(t.keysize))
-		}
-
-		for ; b != nil; b = b.overflow(t) {
-			k := add(unsafe.Pointer(b), dataOffset)
-			e := add(k, bucketCnt*uintptr(t.keysize))
-			for i := 0; i < bucketCnt; i, k, e = i+1, add(k, uintptr(t.keysize)), add(e, uintptr(t.elemsize)) {
-				top := b.tophash[i]
-				if isEmpty(top) {
-					b.tophash[i] = evacuatedEmpty
-					continue
-				}
-				if top < minTopHash {
-					throw("bad map state")
-				}
-				k2 := k
-				if t.indirectkey() {
-					k2 = *((*unsafe.Pointer)(k2))
-				}
-				var useY uint8
-				if !h.sameSizeGrow() {
-					// Compute hash to make our evacuation decision (whether we need
-					// to send this key/elem to bucket x or bucket y).
-					hash := t.hasher(k2, uintptr(h.hash0))
-					if h.flags&iterator != 0 && !t.reflexivekey() && !t.key.equal(k2, k2) {
-						// If key != key (NaNs), then the hash could be (and probably
-						// will be) entirely different from the old hash. Moreover,
-						// it isn't reproducible. Reproducibility is required in the
-						// presence of iterators, as our evacuation decision must
-						// match whatever decision the iterator made.
-						// Fortunately, we have the freedom to send these keys either
-						// way. Also, tophash is meaningless for these kinds of keys.
-						// We let the low bit of tophash drive the evacuation decision.
-						// We recompute a new random tophash for the next level so
-						// these keys will get evenly distributed across all buckets
-						// after multiple grows.
-						useY = top & 1
-						top = tophash(hash)
-					} else {
-						if hash&newbit != 0 {
-							useY = 1
-						}
-					}
-				}
-
-				if evacuatedX+1 != evacuatedY || evacuatedX^1 != evacuatedY {
-					throw("bad evacuatedN")
-				}
-
-				b.tophash[i] = evacuatedX + useY // evacuatedX + 1 == evacuatedY
-				dst := &xy[useY]                 // evacuation destination
-
-				if dst.i == bucketCnt {
-					dst.b = h.newoverflow(t, dst.b)
-					dst.i = 0
-					dst.k = add(unsafe.Pointer(dst.b), dataOffset)
-					dst.e = add(dst.k, bucketCnt*uintptr(t.keysize))
-				}
-				dst.b.tophash[dst.i&(bucketCnt-1)] = top // mask dst.i as an optimization, to avoid a bounds check
-				if t.indirectkey() {
-					*(*unsafe.Pointer)(dst.k) = k2 // copy pointer
-				} else {
-					typedmemmove(t.key, dst.k, k) // copy elem
-				}
-				if t.indirectelem() {
-					*(*unsafe.Pointer)(dst.e) = *(*unsafe.Pointer)(e)
-				} else {
-					typedmemmove(t.elem, dst.e, e)
-				}
-				dst.i++
-				// These updates might push these pointers past the end of the
-				// key or elem arrays.  That's ok, as we have the overflow pointer
-				// at the end of the bucket to protect against pointing past the
-				// end of the bucket.
-				dst.k = add(dst.k, uintptr(t.keysize))
-				dst.e = add(dst.e, uintptr(t.elemsize))
-			}
-		}
-		// Unlink the overflow buckets & clear key/elem to help GC.
-		if h.flags&oldIterator == 0 && t.bucket.ptrdata != 0 {
-			b := add(h.oldbuckets, oldbucket*uintptr(t.bucketsize))
-			// Preserve b.tophash because the evacuation
-			// state is maintained there.
-			ptr := add(b, dataOffset)
-			n := uintptr(t.bucketsize) - dataOffset
-			memclrHasPointers(ptr, n)
-		}
-	}
-
-	if oldbucket == h.nevacuate {
-		advanceEvacuationMark(h, t, newbit)
-	}
-}
-
-func advanceEvacuationMark(h *hmap, t *maptype, newbit uintptr) {
-	h.nevacuate++
-	// Experiments suggest that 1024 is overkill by at least an order of magnitude.
-	// Put it in there as a safeguard anyway, to ensure O(1) behavior.
-	stop := h.nevacuate + 1024
-	if stop > newbit {
-		stop = newbit
-	}
-	for h.nevacuate != stop && bucketEvacuated(t, h, h.nevacuate) {
-		h.nevacuate++
-	}
-	if h.nevacuate == newbit { // newbit == # of oldbuckets
-		// Growing is all done. Free old main bucket array.
-		h.oldbuckets = nil
-		// Can discard old overflow buckets as well.
-		// If they are still referenced by an iterator,
-		// then the iterator holds a pointers to the slice.
-		if h.extra != nil {
-			h.extra.oldoverflow = nil
-		}
-		h.flags &^= sameSizeGrow
-	}
-}
-
-// Reflect stubs. Called from ../reflect/asm_*.s
-
-//go:linkname reflect_makemap reflect.makemap
-func reflect_makemap(t *maptype, cap int) *hmap {
-	// Check invariants and reflects math.
-	if t.key.equal == nil {
-		throw("runtime.reflect_makemap: unsupported map key type")
-	}
-	if t.key.size > maxKeySize && (!t.indirectkey() || t.keysize != uint8(goarch.PtrSize)) ||
-		t.key.size <= maxKeySize && (t.indirectkey() || t.keysize != uint8(t.key.size)) {
-		throw("key size wrong")
-	}
-	if t.elem.size > maxElemSize && (!t.indirectelem() || t.elemsize != uint8(goarch.PtrSize)) ||
-		t.elem.size <= maxElemSize && (t.indirectelem() || t.elemsize != uint8(t.elem.size)) {
-		throw("elem size wrong")
-	}
-	if t.key.align > bucketCnt {
-		throw("key align too big")
-	}
-	if t.elem.align > bucketCnt {
-		throw("elem align too big")
-	}
-	if t.key.size%uintptr(t.key.align) != 0 {
-		throw("key size not a multiple of key align")
-	}
-	if t.elem.size%uintptr(t.elem.align) != 0 {
-		throw("elem size not a multiple of elem align")
-	}
-	if bucketCnt < 8 {
-		throw("bucketsize too small for proper alignment")
-	}
-	if dataOffset%uintptr(t.key.align) != 0 {
-		throw("need padding in bucket (key)")
-	}
-	if dataOffset%uintptr(t.elem.align) != 0 {
-		throw("need padding in bucket (elem)")
-	}
-
-	return makemap(t, cap, nil)
-}
-
-//go:linkname reflect_mapaccess reflect.mapaccess
-func reflect_mapaccess(t *maptype, h *hmap, key unsafe.Pointer) unsafe.Pointer {
-	elem, ok := mapaccess2(t, h, key)
-	if !ok {
-		// reflect wants nil for a missing element
-		elem = nil
-	}
-	return elem
-}
-
-//go:linkname reflect_mapaccess_faststr reflect.mapaccess_faststr
-func reflect_mapaccess_faststr(t *maptype, h *hmap, key string) unsafe.Pointer {
-	elem, ok := mapaccess2_faststr(t, h, key)
-	if !ok {
-		// reflect wants nil for a missing element
-		elem = nil
-	}
-	return elem
-}
-
-//go:linkname reflect_mapassign reflect.mapassign
-func reflect_mapassign(t *maptype, h *hmap, key unsafe.Pointer, elem unsafe.Pointer) {
-	p := mapassign(t, h, key)
-	typedmemmove(t.elem, p, elem)
-}
-
-//go:linkname reflect_mapassign_faststr reflect.mapassign_faststr
-func reflect_mapassign_faststr(t *maptype, h *hmap, key string, elem unsafe.Pointer) {
-	p := mapassign_faststr(t, h, key)
-	typedmemmove(t.elem, p, elem)
-}
-
-//go:linkname reflect_mapdelete reflect.mapdelete
-func reflect_mapdelete(t *maptype, h *hmap, key unsafe.Pointer) {
-	mapdelete(t, h, key)
-}
-
-//go:linkname reflect_mapdelete_faststr reflect.mapdelete_faststr
-func reflect_mapdelete_faststr(t *maptype, h *hmap, key string) {
-	mapdelete_faststr(t, h, key)
-}
-
-//go:linkname reflect_mapiterinit reflect.mapiterinit
-func reflect_mapiterinit(t *maptype, h *hmap, it *hiter) {
-	mapiterinit(t, h, it)
-}
-
-//go:linkname reflect_mapiternext reflect.mapiternext
-func reflect_mapiternext(it *hiter) {
-	mapiternext(it)
-}
-
-//go:linkname reflect_mapiterkey reflect.mapiterkey
-func reflect_mapiterkey(it *hiter) unsafe.Pointer {
-	return it.key
-}
-
-//go:linkname reflect_mapiterelem reflect.mapiterelem
-func reflect_mapiterelem(it *hiter) unsafe.Pointer {
-	return it.elem
-}
-
-//go:linkname reflect_maplen reflect.maplen
-func reflect_maplen(h *hmap) int {
-	if h == nil {
-		return 0
-	}
-	if raceenabled {
-		callerpc := getcallerpc()
-		racereadpc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(reflect_maplen))
-	}
-	return h.count
-}
-
-//go:linkname reflectlite_maplen internal/reflectlite.maplen
-func reflectlite_maplen(h *hmap) int {
-	if h == nil {
-		return 0
-	}
-	if raceenabled {
-		callerpc := getcallerpc()
-		racereadpc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(reflect_maplen))
-	}
-	return h.count
-}
-
-const maxZero = 1024 // must match value in reflect/value.go:maxZero cmd/compile/internal/gc/walk.go:zeroValSize
-var zeroVal [maxZero]byte
diff --git a/contrib/go/_std_1.18/src/runtime/map_fast32.go b/contrib/go/_std_1.18/src/runtime/map_fast32.go
deleted file mode 100644
index e80caeef55..0000000000
--- a/contrib/go/_std_1.18/src/runtime/map_fast32.go
+++ /dev/null
@@ -1,462 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"internal/abi"
-	"internal/goarch"
-	"unsafe"
-)
-
-func mapaccess1_fast32(t *maptype, h *hmap, key uint32) unsafe.Pointer {
-	if raceenabled && h != nil {
-		callerpc := getcallerpc()
-		racereadpc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapaccess1_fast32))
-	}
-	if h == nil || h.count == 0 {
-		return unsafe.Pointer(&zeroVal[0])
-	}
-	if h.flags&hashWriting != 0 {
-		throw("concurrent map read and map write")
-	}
-	var b *bmap
-	if h.B == 0 {
-		// One-bucket table. No need to hash.
-		b = (*bmap)(h.buckets)
-	} else {
-		hash := t.hasher(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
-		m := bucketMask(h.B)
-		b = (*bmap)(add(h.buckets, (hash&m)*uintptr(t.bucketsize)))
-		if c := h.oldbuckets; c != nil {
-			if !h.sameSizeGrow() {
-				// There used to be half as many buckets; mask down one more power of two.
-				m >>= 1
-			}
-			oldb := (*bmap)(add(c, (hash&m)*uintptr(t.bucketsize)))
-			if !evacuated(oldb) {
-				b = oldb
-			}
-		}
-	}
-	for ; b != nil; b = b.overflow(t) {
-		for i, k := uintptr(0), b.keys(); i < bucketCnt; i, k = i+1, add(k, 4) {
-			if *(*uint32)(k) == key && !isEmpty(b.tophash[i]) {
-				return add(unsafe.Pointer(b), dataOffset+bucketCnt*4+i*uintptr(t.elemsize))
-			}
-		}
-	}
-	return unsafe.Pointer(&zeroVal[0])
-}
-
-func mapaccess2_fast32(t *maptype, h *hmap, key uint32) (unsafe.Pointer, bool) {
-	if raceenabled && h != nil {
-		callerpc := getcallerpc()
-		racereadpc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapaccess2_fast32))
-	}
-	if h == nil || h.count == 0 {
-		return unsafe.Pointer(&zeroVal[0]), false
-	}
-	if h.flags&hashWriting != 0 {
-		throw("concurrent map read and map write")
-	}
-	var b *bmap
-	if h.B == 0 {
-		// One-bucket table. No need to hash.
-		b = (*bmap)(h.buckets)
-	} else {
-		hash := t.hasher(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
-		m := bucketMask(h.B)
-		b = (*bmap)(add(h.buckets, (hash&m)*uintptr(t.bucketsize)))
-		if c := h.oldbuckets; c != nil {
-			if !h.sameSizeGrow() {
-				// There used to be half as many buckets; mask down one more power of two.
-				m >>= 1
-			}
-			oldb := (*bmap)(add(c, (hash&m)*uintptr(t.bucketsize)))
-			if !evacuated(oldb) {
-				b = oldb
-			}
-		}
-	}
-	for ; b != nil; b = b.overflow(t) {
-		for i, k := uintptr(0), b.keys(); i < bucketCnt; i, k = i+1, add(k, 4) {
-			if *(*uint32)(k) == key && !isEmpty(b.tophash[i]) {
-				return add(unsafe.Pointer(b), dataOffset+bucketCnt*4+i*uintptr(t.elemsize)), true
-			}
-		}
-	}
-	return unsafe.Pointer(&zeroVal[0]), false
-}
-
-func mapassign_fast32(t *maptype, h *hmap, key uint32) unsafe.Pointer {
-	if h == nil {
-		panic(plainError("assignment to entry in nil map"))
-	}
-	if raceenabled {
-		callerpc := getcallerpc()
-		racewritepc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapassign_fast32))
-	}
-	if h.flags&hashWriting != 0 {
-		throw("concurrent map writes")
-	}
-	hash := t.hasher(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
-
-	// Set hashWriting after calling t.hasher for consistency with mapassign.
-	h.flags ^= hashWriting
-
-	if h.buckets == nil {
-		h.buckets = newobject(t.bucket) // newarray(t.bucket, 1)
-	}
-
-again:
-	bucket := hash & bucketMask(h.B)
-	if h.growing() {
-		growWork_fast32(t, h, bucket)
-	}
-	b := (*bmap)(add(h.buckets, bucket*uintptr(t.bucketsize)))
-
-	var insertb *bmap
-	var inserti uintptr
-	var insertk unsafe.Pointer
-
-bucketloop:
-	for {
-		for i := uintptr(0); i < bucketCnt; i++ {
-			if isEmpty(b.tophash[i]) {
-				if insertb == nil {
-					inserti = i
-					insertb = b
-				}
-				if b.tophash[i] == emptyRest {
-					break bucketloop
-				}
-				continue
-			}
-			k := *((*uint32)(add(unsafe.Pointer(b), dataOffset+i*4)))
-			if k != key {
-				continue
-			}
-			inserti = i
-			insertb = b
-			goto done
-		}
-		ovf := b.overflow(t)
-		if ovf == nil {
-			break
-		}
-		b = ovf
-	}
-
-	// Did not find mapping for key. Allocate new cell & add entry.
-
-	// If we hit the max load factor or we have too many overflow buckets,
-	// and we're not already in the middle of growing, start growing.
-	if !h.growing() && (overLoadFactor(h.count+1, h.B) || tooManyOverflowBuckets(h.noverflow, h.B)) {
-		hashGrow(t, h)
-		goto again // Growing the table invalidates everything, so try again
-	}
-
-	if insertb == nil {
-		// The current bucket and all the overflow buckets connected to it are full, allocate a new one.
-		insertb = h.newoverflow(t, b)
-		inserti = 0 // not necessary, but avoids needlessly spilling inserti
-	}
-	insertb.tophash[inserti&(bucketCnt-1)] = tophash(hash) // mask inserti to avoid bounds checks
-
-	insertk = add(unsafe.Pointer(insertb), dataOffset+inserti*4)
-	// store new key at insert position
-	*(*uint32)(insertk) = key
-
-	h.count++
-
-done:
-	elem := add(unsafe.Pointer(insertb), dataOffset+bucketCnt*4+inserti*uintptr(t.elemsize))
-	if h.flags&hashWriting == 0 {
-		throw("concurrent map writes")
-	}
-	h.flags &^= hashWriting
-	return elem
-}
-
-func mapassign_fast32ptr(t *maptype, h *hmap, key unsafe.Pointer) unsafe.Pointer {
-	if h == nil {
-		panic(plainError("assignment to entry in nil map"))
-	}
-	if raceenabled {
-		callerpc := getcallerpc()
-		racewritepc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapassign_fast32))
-	}
-	if h.flags&hashWriting != 0 {
-		throw("concurrent map writes")
-	}
-	hash := t.hasher(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
-
-	// Set hashWriting after calling t.hasher for consistency with mapassign.
-	h.flags ^= hashWriting
-
-	if h.buckets == nil {
-		h.buckets = newobject(t.bucket) // newarray(t.bucket, 1)
-	}
-
-again:
-	bucket := hash & bucketMask(h.B)
-	if h.growing() {
-		growWork_fast32(t, h, bucket)
-	}
-	b := (*bmap)(add(h.buckets, bucket*uintptr(t.bucketsize)))
-
-	var insertb *bmap
-	var inserti uintptr
-	var insertk unsafe.Pointer
-
-bucketloop:
-	for {
-		for i := uintptr(0); i < bucketCnt; i++ {
-			if isEmpty(b.tophash[i]) {
-				if insertb == nil {
-					inserti = i
-					insertb = b
-				}
-				if b.tophash[i] == emptyRest {
-					break bucketloop
-				}
-				continue
-			}
-			k := *((*unsafe.Pointer)(add(unsafe.Pointer(b), dataOffset+i*4)))
-			if k != key {
-				continue
-			}
-			inserti = i
-			insertb = b
-			goto done
-		}
-		ovf := b.overflow(t)
-		if ovf == nil {
-			break
-		}
-		b = ovf
-	}
-
-	// Did not find mapping for key. Allocate new cell & add entry.
-
-	// If we hit the max load factor or we have too many overflow buckets,
-	// and we're not already in the middle of growing, start growing.
-	if !h.growing() && (overLoadFactor(h.count+1, h.B) || tooManyOverflowBuckets(h.noverflow, h.B)) {
-		hashGrow(t, h)
-		goto again // Growing the table invalidates everything, so try again
-	}
-
-	if insertb == nil {
-		// The current bucket and all the overflow buckets connected to it are full, allocate a new one.
-		insertb = h.newoverflow(t, b)
-		inserti = 0 // not necessary, but avoids needlessly spilling inserti
-	}
-	insertb.tophash[inserti&(bucketCnt-1)] = tophash(hash) // mask inserti to avoid bounds checks
-
-	insertk = add(unsafe.Pointer(insertb), dataOffset+inserti*4)
-	// store new key at insert position
-	*(*unsafe.Pointer)(insertk) = key
-
-	h.count++
-
-done:
-	elem := add(unsafe.Pointer(insertb), dataOffset+bucketCnt*4+inserti*uintptr(t.elemsize))
-	if h.flags&hashWriting == 0 {
-		throw("concurrent map writes")
-	}
-	h.flags &^= hashWriting
-	return elem
-}
-
-func mapdelete_fast32(t *maptype, h *hmap, key uint32) {
-	if raceenabled && h != nil {
-		callerpc := getcallerpc()
-		racewritepc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapdelete_fast32))
-	}
-	if h == nil || h.count == 0 {
-		return
-	}
-	if h.flags&hashWriting != 0 {
-		throw("concurrent map writes")
-	}
-
-	hash := t.hasher(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
-
-	// Set hashWriting after calling t.hasher for consistency with mapdelete
-	h.flags ^= hashWriting
-
-	bucket := hash & bucketMask(h.B)
-	if h.growing() {
-		growWork_fast32(t, h, bucket)
-	}
-	b := (*bmap)(add(h.buckets, bucket*uintptr(t.bucketsize)))
-	bOrig := b
-search:
-	for ; b != nil; b = b.overflow(t) {
-		for i, k := uintptr(0), b.keys(); i < bucketCnt; i, k = i+1, add(k, 4) {
-			if key != *(*uint32)(k) || isEmpty(b.tophash[i]) {
-				continue
-			}
-			// Only clear key if there are pointers in it.
-			// This can only happen if pointers are 32 bit
-			// wide as 64 bit pointers do not fit into a 32 bit key.
-			if goarch.PtrSize == 4 && t.key.ptrdata != 0 {
-				// The key must be a pointer as we checked pointers are
-				// 32 bits wide and the key is 32 bits wide also.
-				*(*unsafe.Pointer)(k) = nil
-			}
-			e := add(unsafe.Pointer(b), dataOffset+bucketCnt*4+i*uintptr(t.elemsize))
-			if t.elem.ptrdata != 0 {
-				memclrHasPointers(e, t.elem.size)
-			} else {
-				memclrNoHeapPointers(e, t.elem.size)
-			}
-			b.tophash[i] = emptyOne
-			// If the bucket now ends in a bunch of emptyOne states,
-			// change those to emptyRest states.
-			if i == bucketCnt-1 {
-				if b.overflow(t) != nil && b.overflow(t).tophash[0] != emptyRest {
-					goto notLast
-				}
-			} else {
-				if b.tophash[i+1] != emptyRest {
-					goto notLast
-				}
-			}
-			for {
-				b.tophash[i] = emptyRest
-				if i == 0 {
-					if b == bOrig {
-						break // beginning of initial bucket, we're done.
-					}
-					// Find previous bucket, continue at its last entry.
-					c := b
-					for b = bOrig; b.overflow(t) != c; b = b.overflow(t) {
-					}
-					i = bucketCnt - 1
-				} else {
-					i--
-				}
-				if b.tophash[i] != emptyOne {
-					break
-				}
-			}
-		notLast:
-			h.count--
-			// Reset the hash seed to make it more difficult for attackers to
-			// repeatedly trigger hash collisions. See issue 25237.
-			if h.count == 0 {
-				h.hash0 = fastrand()
-			}
-			break search
-		}
-	}
-
-	if h.flags&hashWriting == 0 {
-		throw("concurrent map writes")
-	}
-	h.flags &^= hashWriting
-}
-
-func growWork_fast32(t *maptype, h *hmap, bucket uintptr) {
-	// make sure we evacuate the oldbucket corresponding
-	// to the bucket we're about to use
-	evacuate_fast32(t, h, bucket&h.oldbucketmask())
-
-	// evacuate one more oldbucket to make progress on growing
-	if h.growing() {
-		evacuate_fast32(t, h, h.nevacuate)
-	}
-}
-
-func evacuate_fast32(t *maptype, h *hmap, oldbucket uintptr) {
-	b := (*bmap)(add(h.oldbuckets, oldbucket*uintptr(t.bucketsize)))
-	newbit := h.noldbuckets()
-	if !evacuated(b) {
-		// TODO: reuse overflow buckets instead of using new ones, if there
-		// is no iterator using the old buckets.  (If !oldIterator.)
-
-		// xy contains the x and y (low and high) evacuation destinations.
-		var xy [2]evacDst
-		x := &xy[0]
-		x.b = (*bmap)(add(h.buckets, oldbucket*uintptr(t.bucketsize)))
-		x.k = add(unsafe.Pointer(x.b), dataOffset)
-		x.e = add(x.k, bucketCnt*4)
-
-		if !h.sameSizeGrow() {
-			// Only calculate y pointers if we're growing bigger.
-			// Otherwise GC can see bad pointers.
-			y := &xy[1]
-			y.b = (*bmap)(add(h.buckets, (oldbucket+newbit)*uintptr(t.bucketsize)))
-			y.k = add(unsafe.Pointer(y.b), dataOffset)
-			y.e = add(y.k, bucketCnt*4)
-		}
-
-		for ; b != nil; b = b.overflow(t) {
-			k := add(unsafe.Pointer(b), dataOffset)
-			e := add(k, bucketCnt*4)
-			for i := 0; i < bucketCnt; i, k, e = i+1, add(k, 4), add(e, uintptr(t.elemsize)) {
-				top := b.tophash[i]
-				if isEmpty(top) {
-					b.tophash[i] = evacuatedEmpty
-					continue
-				}
-				if top < minTopHash {
-					throw("bad map state")
-				}
-				var useY uint8
-				if !h.sameSizeGrow() {
-					// Compute hash to make our evacuation decision (whether we need
-					// to send this key/elem to bucket x or bucket y).
-					hash := t.hasher(k, uintptr(h.hash0))
-					if hash&newbit != 0 {
-						useY = 1
-					}
-				}
-
-				b.tophash[i] = evacuatedX + useY // evacuatedX + 1 == evacuatedY, enforced in makemap
-				dst := &xy[useY]                 // evacuation destination
-
-				if dst.i == bucketCnt {
-					dst.b = h.newoverflow(t, dst.b)
-					dst.i = 0
-					dst.k = add(unsafe.Pointer(dst.b), dataOffset)
-					dst.e = add(dst.k, bucketCnt*4)
-				}
-				dst.b.tophash[dst.i&(bucketCnt-1)] = top // mask dst.i as an optimization, to avoid a bounds check
-
-				// Copy key.
-				if goarch.PtrSize == 4 && t.key.ptrdata != 0 && writeBarrier.enabled {
-					// Write with a write barrier.
-					*(*unsafe.Pointer)(dst.k) = *(*unsafe.Pointer)(k)
-				} else {
-					*(*uint32)(dst.k) = *(*uint32)(k)
-				}
-
-				typedmemmove(t.elem, dst.e, e)
-				dst.i++
-				// These updates might push these pointers past the end of the
-				// key or elem arrays.  That's ok, as we have the overflow pointer
-				// at the end of the bucket to protect against pointing past the
-				// end of the bucket.
-				dst.k = add(dst.k, 4)
-				dst.e = add(dst.e, uintptr(t.elemsize))
-			}
-		}
-		// Unlink the overflow buckets & clear key/elem to help GC.
-		if h.flags&oldIterator == 0 && t.bucket.ptrdata != 0 {
-			b := add(h.oldbuckets, oldbucket*uintptr(t.bucketsize))
-			// Preserve b.tophash because the evacuation
-			// state is maintained there.
-			ptr := add(b, dataOffset)
-			n := uintptr(t.bucketsize) - dataOffset
-			memclrHasPointers(ptr, n)
-		}
-	}
-
-	if oldbucket == h.nevacuate {
-		advanceEvacuationMark(h, t, newbit)
-	}
-}
diff --git a/contrib/go/_std_1.18/src/runtime/map_fast64.go b/contrib/go/_std_1.18/src/runtime/map_fast64.go
deleted file mode 100644
index 69d8872885..0000000000
--- a/contrib/go/_std_1.18/src/runtime/map_fast64.go
+++ /dev/null
@@ -1,470 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"internal/abi"
-	"internal/goarch"
-	"unsafe"
-)
-
-func mapaccess1_fast64(t *maptype, h *hmap, key uint64) unsafe.Pointer {
-	if raceenabled && h != nil {
-		callerpc := getcallerpc()
-		racereadpc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapaccess1_fast64))
-	}
-	if h == nil || h.count == 0 {
-		return unsafe.Pointer(&zeroVal[0])
-	}
-	if h.flags&hashWriting != 0 {
-		throw("concurrent map read and map write")
-	}
-	var b *bmap
-	if h.B == 0 {
-		// One-bucket table. No need to hash.
-		b = (*bmap)(h.buckets)
-	} else {
-		hash := t.hasher(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
-		m := bucketMask(h.B)
-		b = (*bmap)(add(h.buckets, (hash&m)*uintptr(t.bucketsize)))
-		if c := h.oldbuckets; c != nil {
-			if !h.sameSizeGrow() {
-				// There used to be half as many buckets; mask down one more power of two.
-				m >>= 1
-			}
-			oldb := (*bmap)(add(c, (hash&m)*uintptr(t.bucketsize)))
-			if !evacuated(oldb) {
-				b = oldb
-			}
-		}
-	}
-	for ; b != nil; b = b.overflow(t) {
-		for i, k := uintptr(0), b.keys(); i < bucketCnt; i, k = i+1, add(k, 8) {
-			if *(*uint64)(k) == key && !isEmpty(b.tophash[i]) {
-				return add(unsafe.Pointer(b), dataOffset+bucketCnt*8+i*uintptr(t.elemsize))
-			}
-		}
-	}
-	return unsafe.Pointer(&zeroVal[0])
-}
-
-func mapaccess2_fast64(t *maptype, h *hmap, key uint64) (unsafe.Pointer, bool) {
-	if raceenabled && h != nil {
-		callerpc := getcallerpc()
-		racereadpc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapaccess2_fast64))
-	}
-	if h == nil || h.count == 0 {
-		return unsafe.Pointer(&zeroVal[0]), false
-	}
-	if h.flags&hashWriting != 0 {
-		throw("concurrent map read and map write")
-	}
-	var b *bmap
-	if h.B == 0 {
-		// One-bucket table. No need to hash.
-		b = (*bmap)(h.buckets)
-	} else {
-		hash := t.hasher(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
-		m := bucketMask(h.B)
-		b = (*bmap)(add(h.buckets, (hash&m)*uintptr(t.bucketsize)))
-		if c := h.oldbuckets; c != nil {
-			if !h.sameSizeGrow() {
-				// There used to be half as many buckets; mask down one more power of two.
-				m >>= 1
-			}
-			oldb := (*bmap)(add(c, (hash&m)*uintptr(t.bucketsize)))
-			if !evacuated(oldb) {
-				b = oldb
-			}
-		}
-	}
-	for ; b != nil; b = b.overflow(t) {
-		for i, k := uintptr(0), b.keys(); i < bucketCnt; i, k = i+1, add(k, 8) {
-			if *(*uint64)(k) == key && !isEmpty(b.tophash[i]) {
-				return add(unsafe.Pointer(b), dataOffset+bucketCnt*8+i*uintptr(t.elemsize)), true
-			}
-		}
-	}
-	return unsafe.Pointer(&zeroVal[0]), false
-}
-
-func mapassign_fast64(t *maptype, h *hmap, key uint64) unsafe.Pointer {
-	if h == nil {
-		panic(plainError("assignment to entry in nil map"))
-	}
-	if raceenabled {
-		callerpc := getcallerpc()
-		racewritepc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapassign_fast64))
-	}
-	if h.flags&hashWriting != 0 {
-		throw("concurrent map writes")
-	}
-	hash := t.hasher(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
-
-	// Set hashWriting after calling t.hasher for consistency with mapassign.
-	h.flags ^= hashWriting
-
-	if h.buckets == nil {
-		h.buckets = newobject(t.bucket) // newarray(t.bucket, 1)
-	}
-
-again:
-	bucket := hash & bucketMask(h.B)
-	if h.growing() {
-		growWork_fast64(t, h, bucket)
-	}
-	b := (*bmap)(add(h.buckets, bucket*uintptr(t.bucketsize)))
-
-	var insertb *bmap
-	var inserti uintptr
-	var insertk unsafe.Pointer
-
-bucketloop:
-	for {
-		for i := uintptr(0); i < bucketCnt; i++ {
-			if isEmpty(b.tophash[i]) {
-				if insertb == nil {
-					insertb = b
-					inserti = i
-				}
-				if b.tophash[i] == emptyRest {
-					break bucketloop
-				}
-				continue
-			}
-			k := *((*uint64)(add(unsafe.Pointer(b), dataOffset+i*8)))
-			if k != key {
-				continue
-			}
-			insertb = b
-			inserti = i
-			goto done
-		}
-		ovf := b.overflow(t)
-		if ovf == nil {
-			break
-		}
-		b = ovf
-	}
-
-	// Did not find mapping for key. Allocate new cell & add entry.
-
-	// If we hit the max load factor or we have too many overflow buckets,
-	// and we're not already in the middle of growing, start growing.
-	if !h.growing() && (overLoadFactor(h.count+1, h.B) || tooManyOverflowBuckets(h.noverflow, h.B)) {
-		hashGrow(t, h)
-		goto again // Growing the table invalidates everything, so try again
-	}
-
-	if insertb == nil {
-		// The current bucket and all the overflow buckets connected to it are full, allocate a new one.
-		insertb = h.newoverflow(t, b)
-		inserti = 0 // not necessary, but avoids needlessly spilling inserti
-	}
-	insertb.tophash[inserti&(bucketCnt-1)] = tophash(hash) // mask inserti to avoid bounds checks
-
-	insertk = add(unsafe.Pointer(insertb), dataOffset+inserti*8)
-	// store new key at insert position
-	*(*uint64)(insertk) = key
-
-	h.count++
-
-done:
-	elem := add(unsafe.Pointer(insertb), dataOffset+bucketCnt*8+inserti*uintptr(t.elemsize))
-	if h.flags&hashWriting == 0 {
-		throw("concurrent map writes")
-	}
-	h.flags &^= hashWriting
-	return elem
-}
-
-func mapassign_fast64ptr(t *maptype, h *hmap, key unsafe.Pointer) unsafe.Pointer {
-	if h == nil {
-		panic(plainError("assignment to entry in nil map"))
-	}
-	if raceenabled {
-		callerpc := getcallerpc()
-		racewritepc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapassign_fast64))
-	}
-	if h.flags&hashWriting != 0 {
-		throw("concurrent map writes")
-	}
-	hash := t.hasher(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
-
-	// Set hashWriting after calling t.hasher for consistency with mapassign.
-	h.flags ^= hashWriting
-
-	if h.buckets == nil {
-		h.buckets = newobject(t.bucket) // newarray(t.bucket, 1)
-	}
-
-again:
-	bucket := hash & bucketMask(h.B)
-	if h.growing() {
-		growWork_fast64(t, h, bucket)
-	}
-	b := (*bmap)(add(h.buckets, bucket*uintptr(t.bucketsize)))
-
-	var insertb *bmap
-	var inserti uintptr
-	var insertk unsafe.Pointer
-
-bucketloop:
-	for {
-		for i := uintptr(0); i < bucketCnt; i++ {
-			if isEmpty(b.tophash[i]) {
-				if insertb == nil {
-					insertb = b
-					inserti = i
-				}
-				if b.tophash[i] == emptyRest {
-					break bucketloop
-				}
-				continue
-			}
-			k := *((*unsafe.Pointer)(add(unsafe.Pointer(b), dataOffset+i*8)))
-			if k != key {
-				continue
-			}
-			insertb = b
-			inserti = i
-			goto done
-		}
-		ovf := b.overflow(t)
-		if ovf == nil {
-			break
-		}
-		b = ovf
-	}
-
-	// Did not find mapping for key. Allocate new cell & add entry.
-
-	// If we hit the max load factor or we have too many overflow buckets,
-	// and we're not already in the middle of growing, start growing.
-	if !h.growing() && (overLoadFactor(h.count+1, h.B) || tooManyOverflowBuckets(h.noverflow, h.B)) {
-		hashGrow(t, h)
-		goto again // Growing the table invalidates everything, so try again
-	}
-
-	if insertb == nil {
-		// The current bucket and all the overflow buckets connected to it are full, allocate a new one.
-		insertb = h.newoverflow(t, b)
-		inserti = 0 // not necessary, but avoids needlessly spilling inserti
-	}
-	insertb.tophash[inserti&(bucketCnt-1)] = tophash(hash) // mask inserti to avoid bounds checks
-
-	insertk = add(unsafe.Pointer(insertb), dataOffset+inserti*8)
-	// store new key at insert position
-	*(*unsafe.Pointer)(insertk) = key
-
-	h.count++
-
-done:
-	elem := add(unsafe.Pointer(insertb), dataOffset+bucketCnt*8+inserti*uintptr(t.elemsize))
-	if h.flags&hashWriting == 0 {
-		throw("concurrent map writes")
-	}
-	h.flags &^= hashWriting
-	return elem
-}
-
-func mapdelete_fast64(t *maptype, h *hmap, key uint64) {
-	if raceenabled && h != nil {
-		callerpc := getcallerpc()
-		racewritepc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapdelete_fast64))
-	}
-	if h == nil || h.count == 0 {
-		return
-	}
-	if h.flags&hashWriting != 0 {
-		throw("concurrent map writes")
-	}
-
-	hash := t.hasher(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
-
-	// Set hashWriting after calling t.hasher for consistency with mapdelete
-	h.flags ^= hashWriting
-
-	bucket := hash & bucketMask(h.B)
-	if h.growing() {
-		growWork_fast64(t, h, bucket)
-	}
-	b := (*bmap)(add(h.buckets, bucket*uintptr(t.bucketsize)))
-	bOrig := b
-search:
-	for ; b != nil; b = b.overflow(t) {
-		for i, k := uintptr(0), b.keys(); i < bucketCnt; i, k = i+1, add(k, 8) {
-			if key != *(*uint64)(k) || isEmpty(b.tophash[i]) {
-				continue
-			}
-			// Only clear key if there are pointers in it.
-			if t.key.ptrdata != 0 {
-				if goarch.PtrSize == 8 {
-					*(*unsafe.Pointer)(k) = nil
-				} else {
-					// There are three ways to squeeze at one ore more 32 bit pointers into 64 bits.
-					// Just call memclrHasPointers instead of trying to handle all cases here.
-					memclrHasPointers(k, 8)
-				}
-			}
-			e := add(unsafe.Pointer(b), dataOffset+bucketCnt*8+i*uintptr(t.elemsize))
-			if t.elem.ptrdata != 0 {
-				memclrHasPointers(e, t.elem.size)
-			} else {
-				memclrNoHeapPointers(e, t.elem.size)
-			}
-			b.tophash[i] = emptyOne
-			// If the bucket now ends in a bunch of emptyOne states,
-			// change those to emptyRest states.
-			if i == bucketCnt-1 {
-				if b.overflow(t) != nil && b.overflow(t).tophash[0] != emptyRest {
-					goto notLast
-				}
-			} else {
-				if b.tophash[i+1] != emptyRest {
-					goto notLast
-				}
-			}
-			for {
-				b.tophash[i] = emptyRest
-				if i == 0 {
-					if b == bOrig {
-						break // beginning of initial bucket, we're done.
-					}
-					// Find previous bucket, continue at its last entry.
-					c := b
-					for b = bOrig; b.overflow(t) != c; b = b.overflow(t) {
-					}
-					i = bucketCnt - 1
-				} else {
-					i--
-				}
-				if b.tophash[i] != emptyOne {
-					break
-				}
-			}
-		notLast:
-			h.count--
-			// Reset the hash seed to make it more difficult for attackers to
-			// repeatedly trigger hash collisions. See issue 25237.
-			if h.count == 0 {
-				h.hash0 = fastrand()
-			}
-			break search
-		}
-	}
-
-	if h.flags&hashWriting == 0 {
-		throw("concurrent map writes")
-	}
-	h.flags &^= hashWriting
-}
-
-func growWork_fast64(t *maptype, h *hmap, bucket uintptr) {
-	// make sure we evacuate the oldbucket corresponding
-	// to the bucket we're about to use
-	evacuate_fast64(t, h, bucket&h.oldbucketmask())
-
-	// evacuate one more oldbucket to make progress on growing
-	if h.growing() {
-		evacuate_fast64(t, h, h.nevacuate)
-	}
-}
-
-func evacuate_fast64(t *maptype, h *hmap, oldbucket uintptr) {
-	b := (*bmap)(add(h.oldbuckets, oldbucket*uintptr(t.bucketsize)))
-	newbit := h.noldbuckets()
-	if !evacuated(b) {
-		// TODO: reuse overflow buckets instead of using new ones, if there
-		// is no iterator using the old buckets.  (If !oldIterator.)
-
-		// xy contains the x and y (low and high) evacuation destinations.
-		var xy [2]evacDst
-		x := &xy[0]
-		x.b = (*bmap)(add(h.buckets, oldbucket*uintptr(t.bucketsize)))
-		x.k = add(unsafe.Pointer(x.b), dataOffset)
-		x.e = add(x.k, bucketCnt*8)
-
-		if !h.sameSizeGrow() {
-			// Only calculate y pointers if we're growing bigger.
-			// Otherwise GC can see bad pointers.
-			y := &xy[1]
-			y.b = (*bmap)(add(h.buckets, (oldbucket+newbit)*uintptr(t.bucketsize)))
-			y.k = add(unsafe.Pointer(y.b), dataOffset)
-			y.e = add(y.k, bucketCnt*8)
-		}
-
-		for ; b != nil; b = b.overflow(t) {
-			k := add(unsafe.Pointer(b), dataOffset)
-			e := add(k, bucketCnt*8)
-			for i := 0; i < bucketCnt; i, k, e = i+1, add(k, 8), add(e, uintptr(t.elemsize)) {
-				top := b.tophash[i]
-				if isEmpty(top) {
-					b.tophash[i] = evacuatedEmpty
-					continue
-				}
-				if top < minTopHash {
-					throw("bad map state")
-				}
-				var useY uint8
-				if !h.sameSizeGrow() {
-					// Compute hash to make our evacuation decision (whether we need
-					// to send this key/elem to bucket x or bucket y).
-					hash := t.hasher(k, uintptr(h.hash0))
-					if hash&newbit != 0 {
-						useY = 1
-					}
-				}
-
-				b.tophash[i] = evacuatedX + useY // evacuatedX + 1 == evacuatedY, enforced in makemap
-				dst := &xy[useY]                 // evacuation destination
-
-				if dst.i == bucketCnt {
-					dst.b = h.newoverflow(t, dst.b)
-					dst.i = 0
-					dst.k = add(unsafe.Pointer(dst.b), dataOffset)
-					dst.e = add(dst.k, bucketCnt*8)
-				}
-				dst.b.tophash[dst.i&(bucketCnt-1)] = top // mask dst.i as an optimization, to avoid a bounds check
-
-				// Copy key.
-				if t.key.ptrdata != 0 && writeBarrier.enabled {
-					if goarch.PtrSize == 8 {
-						// Write with a write barrier.
-						*(*unsafe.Pointer)(dst.k) = *(*unsafe.Pointer)(k)
-					} else {
-						// There are three ways to squeeze at least one 32 bit pointer into 64 bits.
-						// Give up and call typedmemmove.
-						typedmemmove(t.key, dst.k, k)
-					}
-				} else {
-					*(*uint64)(dst.k) = *(*uint64)(k)
-				}
-
-				typedmemmove(t.elem, dst.e, e)
-				dst.i++
-				// These updates might push these pointers past the end of the
-				// key or elem arrays.  That's ok, as we have the overflow pointer
-				// at the end of the bucket to protect against pointing past the
-				// end of the bucket.
-				dst.k = add(dst.k, 8)
-				dst.e = add(dst.e, uintptr(t.elemsize))
-			}
-		}
-		// Unlink the overflow buckets & clear key/elem to help GC.
-		if h.flags&oldIterator == 0 && t.bucket.ptrdata != 0 {
-			b := add(h.oldbuckets, oldbucket*uintptr(t.bucketsize))
-			// Preserve b.tophash because the evacuation
-			// state is maintained there.
-			ptr := add(b, dataOffset)
-			n := uintptr(t.bucketsize) - dataOffset
-			memclrHasPointers(ptr, n)
-		}
-	}
-
-	if oldbucket == h.nevacuate {
-		advanceEvacuationMark(h, t, newbit)
-	}
-}
diff --git a/contrib/go/_std_1.18/src/runtime/map_faststr.go b/contrib/go/_std_1.18/src/runtime/map_faststr.go
deleted file mode 100644
index 4dca882c63..0000000000
--- a/contrib/go/_std_1.18/src/runtime/map_faststr.go
+++ /dev/null
@@ -1,485 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"internal/abi"
-	"internal/goarch"
-	"unsafe"
-)
-
-func mapaccess1_faststr(t *maptype, h *hmap, ky string) unsafe.Pointer {
-	if raceenabled && h != nil {
-		callerpc := getcallerpc()
-		racereadpc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapaccess1_faststr))
-	}
-	if h == nil || h.count == 0 {
-		return unsafe.Pointer(&zeroVal[0])
-	}
-	if h.flags&hashWriting != 0 {
-		throw("concurrent map read and map write")
-	}
-	key := stringStructOf(&ky)
-	if h.B == 0 {
-		// One-bucket table.
-		b := (*bmap)(h.buckets)
-		if key.len < 32 {
-			// short key, doing lots of comparisons is ok
-			for i, kptr := uintptr(0), b.keys(); i < bucketCnt; i, kptr = i+1, add(kptr, 2*goarch.PtrSize) {
-				k := (*stringStruct)(kptr)
-				if k.len != key.len || isEmpty(b.tophash[i]) {
-					if b.tophash[i] == emptyRest {
-						break
-					}
-					continue
-				}
-				if k.str == key.str || memequal(k.str, key.str, uintptr(key.len)) {
-					return add(unsafe.Pointer(b), dataOffset+bucketCnt*2*goarch.PtrSize+i*uintptr(t.elemsize))
-				}
-			}
-			return unsafe.Pointer(&zeroVal[0])
-		}
-		// long key, try not to do more comparisons than necessary
-		keymaybe := uintptr(bucketCnt)
-		for i, kptr := uintptr(0), b.keys(); i < bucketCnt; i, kptr = i+1, add(kptr, 2*goarch.PtrSize) {
-			k := (*stringStruct)(kptr)
-			if k.len != key.len || isEmpty(b.tophash[i]) {
-				if b.tophash[i] == emptyRest {
-					break
-				}
-				continue
-			}
-			if k.str == key.str {
-				return add(unsafe.Pointer(b), dataOffset+bucketCnt*2*goarch.PtrSize+i*uintptr(t.elemsize))
-			}
-			// check first 4 bytes
-			if *((*[4]byte)(key.str)) != *((*[4]byte)(k.str)) {
-				continue
-			}
-			// check last 4 bytes
-			if *((*[4]byte)(add(key.str, uintptr(key.len)-4))) != *((*[4]byte)(add(k.str, uintptr(key.len)-4))) {
-				continue
-			}
-			if keymaybe != bucketCnt {
-				// Two keys are potential matches. Use hash to distinguish them.
-				goto dohash
-			}
-			keymaybe = i
-		}
-		if keymaybe != bucketCnt {
-			k := (*stringStruct)(add(unsafe.Pointer(b), dataOffset+keymaybe*2*goarch.PtrSize))
-			if memequal(k.str, key.str, uintptr(key.len)) {
-				return add(unsafe.Pointer(b), dataOffset+bucketCnt*2*goarch.PtrSize+keymaybe*uintptr(t.elemsize))
-			}
-		}
-		return unsafe.Pointer(&zeroVal[0])
-	}
-dohash:
-	hash := t.hasher(noescape(unsafe.Pointer(&ky)), uintptr(h.hash0))
-	m := bucketMask(h.B)
-	b := (*bmap)(add(h.buckets, (hash&m)*uintptr(t.bucketsize)))
-	if c := h.oldbuckets; c != nil {
-		if !h.sameSizeGrow() {
-			// There used to be half as many buckets; mask down one more power of two.
-			m >>= 1
-		}
-		oldb := (*bmap)(add(c, (hash&m)*uintptr(t.bucketsize)))
-		if !evacuated(oldb) {
-			b = oldb
-		}
-	}
-	top := tophash(hash)
-	for ; b != nil; b = b.overflow(t) {
-		for i, kptr := uintptr(0), b.keys(); i < bucketCnt; i, kptr = i+1, add(kptr, 2*goarch.PtrSize) {
-			k := (*stringStruct)(kptr)
-			if k.len != key.len || b.tophash[i] != top {
-				continue
-			}
-			if k.str == key.str || memequal(k.str, key.str, uintptr(key.len)) {
-				return add(unsafe.Pointer(b), dataOffset+bucketCnt*2*goarch.PtrSize+i*uintptr(t.elemsize))
-			}
-		}
-	}
-	return unsafe.Pointer(&zeroVal[0])
-}
-
-func mapaccess2_faststr(t *maptype, h *hmap, ky string) (unsafe.Pointer, bool) {
-	if raceenabled && h != nil {
-		callerpc := getcallerpc()
-		racereadpc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapaccess2_faststr))
-	}
-	if h == nil || h.count == 0 {
-		return unsafe.Pointer(&zeroVal[0]), false
-	}
-	if h.flags&hashWriting != 0 {
-		throw("concurrent map read and map write")
-	}
-	key := stringStructOf(&ky)
-	if h.B == 0 {
-		// One-bucket table.
-		b := (*bmap)(h.buckets)
-		if key.len < 32 {
-			// short key, doing lots of comparisons is ok
-			for i, kptr := uintptr(0), b.keys(); i < bucketCnt; i, kptr = i+1, add(kptr, 2*goarch.PtrSize) {
-				k := (*stringStruct)(kptr)
-				if k.len != key.len || isEmpty(b.tophash[i]) {
-					if b.tophash[i] == emptyRest {
-						break
-					}
-					continue
-				}
-				if k.str == key.str || memequal(k.str, key.str, uintptr(key.len)) {
-					return add(unsafe.Pointer(b), dataOffset+bucketCnt*2*goarch.PtrSize+i*uintptr(t.elemsize)), true
-				}
-			}
-			return unsafe.Pointer(&zeroVal[0]), false
-		}
-		// long key, try not to do more comparisons than necessary
-		keymaybe := uintptr(bucketCnt)
-		for i, kptr := uintptr(0), b.keys(); i < bucketCnt; i, kptr = i+1, add(kptr, 2*goarch.PtrSize) {
-			k := (*stringStruct)(kptr)
-			if k.len != key.len || isEmpty(b.tophash[i]) {
-				if b.tophash[i] == emptyRest {
-					break
-				}
-				continue
-			}
-			if k.str == key.str {
-				return add(unsafe.Pointer(b), dataOffset+bucketCnt*2*goarch.PtrSize+i*uintptr(t.elemsize)), true
-			}
-			// check first 4 bytes
-			if *((*[4]byte)(key.str)) != *((*[4]byte)(k.str)) {
-				continue
-			}
-			// check last 4 bytes
-			if *((*[4]byte)(add(key.str, uintptr(key.len)-4))) != *((*[4]byte)(add(k.str, uintptr(key.len)-4))) {
-				continue
-			}
-			if keymaybe != bucketCnt {
-				// Two keys are potential matches. Use hash to distinguish them.
-				goto dohash
-			}
-			keymaybe = i
-		}
-		if keymaybe != bucketCnt {
-			k := (*stringStruct)(add(unsafe.Pointer(b), dataOffset+keymaybe*2*goarch.PtrSize))
-			if memequal(k.str, key.str, uintptr(key.len)) {
-				return add(unsafe.Pointer(b), dataOffset+bucketCnt*2*goarch.PtrSize+keymaybe*uintptr(t.elemsize)), true
-			}
-		}
-		return unsafe.Pointer(&zeroVal[0]), false
-	}
-dohash:
-	hash := t.hasher(noescape(unsafe.Pointer(&ky)), uintptr(h.hash0))
-	m := bucketMask(h.B)
-	b := (*bmap)(add(h.buckets, (hash&m)*uintptr(t.bucketsize)))
-	if c := h.oldbuckets; c != nil {
-		if !h.sameSizeGrow() {
-			// There used to be half as many buckets; mask down one more power of two.
-			m >>= 1
-		}
-		oldb := (*bmap)(add(c, (hash&m)*uintptr(t.bucketsize)))
-		if !evacuated(oldb) {
-			b = oldb
-		}
-	}
-	top := tophash(hash)
-	for ; b != nil; b = b.overflow(t) {
-		for i, kptr := uintptr(0), b.keys(); i < bucketCnt; i, kptr = i+1, add(kptr, 2*goarch.PtrSize) {
-			k := (*stringStruct)(kptr)
-			if k.len != key.len || b.tophash[i] != top {
-				continue
-			}
-			if k.str == key.str || memequal(k.str, key.str, uintptr(key.len)) {
-				return add(unsafe.Pointer(b), dataOffset+bucketCnt*2*goarch.PtrSize+i*uintptr(t.elemsize)), true
-			}
-		}
-	}
-	return unsafe.Pointer(&zeroVal[0]), false
-}
-
-func mapassign_faststr(t *maptype, h *hmap, s string) unsafe.Pointer {
-	if h == nil {
-		panic(plainError("assignment to entry in nil map"))
-	}
-	if raceenabled {
-		callerpc := getcallerpc()
-		racewritepc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapassign_faststr))
-	}
-	if h.flags&hashWriting != 0 {
-		throw("concurrent map writes")
-	}
-	key := stringStructOf(&s)
-	hash := t.hasher(noescape(unsafe.Pointer(&s)), uintptr(h.hash0))
-
-	// Set hashWriting after calling t.hasher for consistency with mapassign.
-	h.flags ^= hashWriting
-
-	if h.buckets == nil {
-		h.buckets = newobject(t.bucket) // newarray(t.bucket, 1)
-	}
-
-again:
-	bucket := hash & bucketMask(h.B)
-	if h.growing() {
-		growWork_faststr(t, h, bucket)
-	}
-	b := (*bmap)(add(h.buckets, bucket*uintptr(t.bucketsize)))
-	top := tophash(hash)
-
-	var insertb *bmap
-	var inserti uintptr
-	var insertk unsafe.Pointer
-
-bucketloop:
-	for {
-		for i := uintptr(0); i < bucketCnt; i++ {
-			if b.tophash[i] != top {
-				if isEmpty(b.tophash[i]) && insertb == nil {
-					insertb = b
-					inserti = i
-				}
-				if b.tophash[i] == emptyRest {
-					break bucketloop
-				}
-				continue
-			}
-			k := (*stringStruct)(add(unsafe.Pointer(b), dataOffset+i*2*goarch.PtrSize))
-			if k.len != key.len {
-				continue
-			}
-			if k.str != key.str && !memequal(k.str, key.str, uintptr(key.len)) {
-				continue
-			}
-			// already have a mapping for key. Update it.
-			inserti = i
-			insertb = b
-			// Overwrite existing key, so it can be garbage collected.
-			// The size is already guaranteed to be set correctly.
-			k.str = key.str
-			goto done
-		}
-		ovf := b.overflow(t)
-		if ovf == nil {
-			break
-		}
-		b = ovf
-	}
-
-	// Did not find mapping for key. Allocate new cell & add entry.
-
-	// If we hit the max load factor or we have too many overflow buckets,
-	// and we're not already in the middle of growing, start growing.
-	if !h.growing() && (overLoadFactor(h.count+1, h.B) || tooManyOverflowBuckets(h.noverflow, h.B)) {
-		hashGrow(t, h)
-		goto again // Growing the table invalidates everything, so try again
-	}
-
-	if insertb == nil {
-		// The current bucket and all the overflow buckets connected to it are full, allocate a new one.
-		insertb = h.newoverflow(t, b)
-		inserti = 0 // not necessary, but avoids needlessly spilling inserti
-	}
-	insertb.tophash[inserti&(bucketCnt-1)] = top // mask inserti to avoid bounds checks
-
-	insertk = add(unsafe.Pointer(insertb), dataOffset+inserti*2*goarch.PtrSize)
-	// store new key at insert position
-	*((*stringStruct)(insertk)) = *key
-	h.count++
-
-done:
-	elem := add(unsafe.Pointer(insertb), dataOffset+bucketCnt*2*goarch.PtrSize+inserti*uintptr(t.elemsize))
-	if h.flags&hashWriting == 0 {
-		throw("concurrent map writes")
-	}
-	h.flags &^= hashWriting
-	return elem
-}
-
-func mapdelete_faststr(t *maptype, h *hmap, ky string) {
-	if raceenabled && h != nil {
-		callerpc := getcallerpc()
-		racewritepc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapdelete_faststr))
-	}
-	if h == nil || h.count == 0 {
-		return
-	}
-	if h.flags&hashWriting != 0 {
-		throw("concurrent map writes")
-	}
-
-	key := stringStructOf(&ky)
-	hash := t.hasher(noescape(unsafe.Pointer(&ky)), uintptr(h.hash0))
-
-	// Set hashWriting after calling t.hasher for consistency with mapdelete
-	h.flags ^= hashWriting
-
-	bucket := hash & bucketMask(h.B)
-	if h.growing() {
-		growWork_faststr(t, h, bucket)
-	}
-	b := (*bmap)(add(h.buckets, bucket*uintptr(t.bucketsize)))
-	bOrig := b
-	top := tophash(hash)
-search:
-	for ; b != nil; b = b.overflow(t) {
-		for i, kptr := uintptr(0), b.keys(); i < bucketCnt; i, kptr = i+1, add(kptr, 2*goarch.PtrSize) {
-			k := (*stringStruct)(kptr)
-			if k.len != key.len || b.tophash[i] != top {
-				continue
-			}
-			if k.str != key.str && !memequal(k.str, key.str, uintptr(key.len)) {
-				continue
-			}
-			// Clear key's pointer.
-			k.str = nil
-			e := add(unsafe.Pointer(b), dataOffset+bucketCnt*2*goarch.PtrSize+i*uintptr(t.elemsize))
-			if t.elem.ptrdata != 0 {
-				memclrHasPointers(e, t.elem.size)
-			} else {
-				memclrNoHeapPointers(e, t.elem.size)
-			}
-			b.tophash[i] = emptyOne
-			// If the bucket now ends in a bunch of emptyOne states,
-			// change those to emptyRest states.
-			if i == bucketCnt-1 {
-				if b.overflow(t) != nil && b.overflow(t).tophash[0] != emptyRest {
-					goto notLast
-				}
-			} else {
-				if b.tophash[i+1] != emptyRest {
-					goto notLast
-				}
-			}
-			for {
-				b.tophash[i] = emptyRest
-				if i == 0 {
-					if b == bOrig {
-						break // beginning of initial bucket, we're done.
-					}
-					// Find previous bucket, continue at its last entry.
-					c := b
-					for b = bOrig; b.overflow(t) != c; b = b.overflow(t) {
-					}
-					i = bucketCnt - 1
-				} else {
-					i--
-				}
-				if b.tophash[i] != emptyOne {
-					break
-				}
-			}
-		notLast:
-			h.count--
-			// Reset the hash seed to make it more difficult for attackers to
-			// repeatedly trigger hash collisions. See issue 25237.
-			if h.count == 0 {
-				h.hash0 = fastrand()
-			}
-			break search
-		}
-	}
-
-	if h.flags&hashWriting == 0 {
-		throw("concurrent map writes")
-	}
-	h.flags &^= hashWriting
-}
-
-func growWork_faststr(t *maptype, h *hmap, bucket uintptr) {
-	// make sure we evacuate the oldbucket corresponding
-	// to the bucket we're about to use
-	evacuate_faststr(t, h, bucket&h.oldbucketmask())
-
-	// evacuate one more oldbucket to make progress on growing
-	if h.growing() {
-		evacuate_faststr(t, h, h.nevacuate)
-	}
-}
-
-func evacuate_faststr(t *maptype, h *hmap, oldbucket uintptr) {
-	b := (*bmap)(add(h.oldbuckets, oldbucket*uintptr(t.bucketsize)))
-	newbit := h.noldbuckets()
-	if !evacuated(b) {
-		// TODO: reuse overflow buckets instead of using new ones, if there
-		// is no iterator using the old buckets.  (If !oldIterator.)
-
-		// xy contains the x and y (low and high) evacuation destinations.
-		var xy [2]evacDst
-		x := &xy[0]
-		x.b = (*bmap)(add(h.buckets, oldbucket*uintptr(t.bucketsize)))
-		x.k = add(unsafe.Pointer(x.b), dataOffset)
-		x.e = add(x.k, bucketCnt*2*goarch.PtrSize)
-
-		if !h.sameSizeGrow() {
-			// Only calculate y pointers if we're growing bigger.
-			// Otherwise GC can see bad pointers.
-			y := &xy[1]
-			y.b = (*bmap)(add(h.buckets, (oldbucket+newbit)*uintptr(t.bucketsize)))
-			y.k = add(unsafe.Pointer(y.b), dataOffset)
-			y.e = add(y.k, bucketCnt*2*goarch.PtrSize)
-		}
-
-		for ; b != nil; b = b.overflow(t) {
-			k := add(unsafe.Pointer(b), dataOffset)
-			e := add(k, bucketCnt*2*goarch.PtrSize)
-			for i := 0; i < bucketCnt; i, k, e = i+1, add(k, 2*goarch.PtrSize), add(e, uintptr(t.elemsize)) {
-				top := b.tophash[i]
-				if isEmpty(top) {
-					b.tophash[i] = evacuatedEmpty
-					continue
-				}
-				if top < minTopHash {
-					throw("bad map state")
-				}
-				var useY uint8
-				if !h.sameSizeGrow() {
-					// Compute hash to make our evacuation decision (whether we need
-					// to send this key/elem to bucket x or bucket y).
-					hash := t.hasher(k, uintptr(h.hash0))
-					if hash&newbit != 0 {
-						useY = 1
-					}
-				}
-
-				b.tophash[i] = evacuatedX + useY // evacuatedX + 1 == evacuatedY, enforced in makemap
-				dst := &xy[useY]                 // evacuation destination
-
-				if dst.i == bucketCnt {
-					dst.b = h.newoverflow(t, dst.b)
-					dst.i = 0
-					dst.k = add(unsafe.Pointer(dst.b), dataOffset)
-					dst.e = add(dst.k, bucketCnt*2*goarch.PtrSize)
-				}
-				dst.b.tophash[dst.i&(bucketCnt-1)] = top // mask dst.i as an optimization, to avoid a bounds check
-
-				// Copy key.
-				*(*string)(dst.k) = *(*string)(k)
-
-				typedmemmove(t.elem, dst.e, e)
-				dst.i++
-				// These updates might push these pointers past the end of the
-				// key or elem arrays.  That's ok, as we have the overflow pointer
-				// at the end of the bucket to protect against pointing past the
-				// end of the bucket.
-				dst.k = add(dst.k, 2*goarch.PtrSize)
-				dst.e = add(dst.e, uintptr(t.elemsize))
-			}
-		}
-		// Unlink the overflow buckets & clear key/elem to help GC.
-		if h.flags&oldIterator == 0 && t.bucket.ptrdata != 0 {
-			b := add(h.oldbuckets, oldbucket*uintptr(t.bucketsize))
-			// Preserve b.tophash because the evacuation
-			// state is maintained there.
-			ptr := add(b, dataOffset)
-			n := uintptr(t.bucketsize) - dataOffset
-			memclrHasPointers(ptr, n)
-		}
-	}
-
-	if oldbucket == h.nevacuate {
-		advanceEvacuationMark(h, t, newbit)
-	}
-}
diff --git a/contrib/go/_std_1.18/src/runtime/mbarrier.go b/contrib/go/_std_1.18/src/runtime/mbarrier.go
deleted file mode 100644
index 465c21f83f..0000000000
--- a/contrib/go/_std_1.18/src/runtime/mbarrier.go
+++ /dev/null
@@ -1,343 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Garbage collector: write barriers.
-//
-// For the concurrent garbage collector, the Go compiler implements
-// updates to pointer-valued fields that may be in heap objects by
-// emitting calls to write barriers. The main write barrier for
-// individual pointer writes is gcWriteBarrier and is implemented in
-// assembly. This file contains write barrier entry points for bulk
-// operations. See also mwbbuf.go.
-
-package runtime
-
-import (
-	"internal/abi"
-	"internal/goarch"
-	"unsafe"
-)
-
-// Go uses a hybrid barrier that combines a Yuasa-style deletion
-// barrier—which shades the object whose reference is being
-// overwritten—with Dijkstra insertion barrier—which shades the object
-// whose reference is being written. The insertion part of the barrier
-// is necessary while the calling goroutine's stack is grey. In
-// pseudocode, the barrier is:
-//
-//     writePointer(slot, ptr):
-//         shade(*slot)
-//         if current stack is grey:
-//             shade(ptr)
-//         *slot = ptr
-//
-// slot is the destination in Go code.
-// ptr is the value that goes into the slot in Go code.
-//
-// Shade indicates that it has seen a white pointer by adding the referent
-// to wbuf as well as marking it.
-//
-// The two shades and the condition work together to prevent a mutator
-// from hiding an object from the garbage collector:
-//
-// 1. shade(*slot) prevents a mutator from hiding an object by moving
-// the sole pointer to it from the heap to its stack. If it attempts
-// to unlink an object from the heap, this will shade it.
-//
-// 2. shade(ptr) prevents a mutator from hiding an object by moving
-// the sole pointer to it from its stack into a black object in the
-// heap. If it attempts to install the pointer into a black object,
-// this will shade it.
-//
-// 3. Once a goroutine's stack is black, the shade(ptr) becomes
-// unnecessary. shade(ptr) prevents hiding an object by moving it from
-// the stack to the heap, but this requires first having a pointer
-// hidden on the stack. Immediately after a stack is scanned, it only
-// points to shaded objects, so it's not hiding anything, and the
-// shade(*slot) prevents it from hiding any other pointers on its
-// stack.
-//
-// For a detailed description of this barrier and proof of
-// correctness, see https://github.com/golang/proposal/blob/master/design/17503-eliminate-rescan.md
-//
-//
-//
-// Dealing with memory ordering:
-//
-// Both the Yuasa and Dijkstra barriers can be made conditional on the
-// color of the object containing the slot. We chose not to make these
-// conditional because the cost of ensuring that the object holding
-// the slot doesn't concurrently change color without the mutator
-// noticing seems prohibitive.
-//
-// Consider the following example where the mutator writes into
-// a slot and then loads the slot's mark bit while the GC thread
-// writes to the slot's mark bit and then as part of scanning reads
-// the slot.
-//
-// Initially both [slot] and [slotmark] are 0 (nil)
-// Mutator thread          GC thread
-// st [slot], ptr          st [slotmark], 1
-//
-// ld r1, [slotmark]       ld r2, [slot]
-//
-// Without an expensive memory barrier between the st and the ld, the final
-// result on most HW (including 386/amd64) can be r1==r2==0. This is a classic
-// example of what can happen when loads are allowed to be reordered with older
-// stores (avoiding such reorderings lies at the heart of the classic
-// Peterson/Dekker algorithms for mutual exclusion). Rather than require memory
-// barriers, which will slow down both the mutator and the GC, we always grey
-// the ptr object regardless of the slot's color.
-//
-// Another place where we intentionally omit memory barriers is when
-// accessing mheap_.arena_used to check if a pointer points into the
-// heap. On relaxed memory machines, it's possible for a mutator to
-// extend the size of the heap by updating arena_used, allocate an
-// object from this new region, and publish a pointer to that object,
-// but for tracing running on another processor to observe the pointer
-// but use the old value of arena_used. In this case, tracing will not
-// mark the object, even though it's reachable. However, the mutator
-// is guaranteed to execute a write barrier when it publishes the
-// pointer, so it will take care of marking the object. A general
-// consequence of this is that the garbage collector may cache the
-// value of mheap_.arena_used. (See issue #9984.)
-//
-//
-// Stack writes:
-//
-// The compiler omits write barriers for writes to the current frame,
-// but if a stack pointer has been passed down the call stack, the
-// compiler will generate a write barrier for writes through that
-// pointer (because it doesn't know it's not a heap pointer).
-//
-// One might be tempted to ignore the write barrier if slot points
-// into to the stack. Don't do it! Mark termination only re-scans
-// frames that have potentially been active since the concurrent scan,
-// so it depends on write barriers to track changes to pointers in
-// stack frames that have not been active.
-//
-//
-// Global writes:
-//
-// The Go garbage collector requires write barriers when heap pointers
-// are stored in globals. Many garbage collectors ignore writes to
-// globals and instead pick up global -> heap pointers during
-// termination. This increases pause time, so we instead rely on write
-// barriers for writes to globals so that we don't have to rescan
-// global during mark termination.
-//
-//
-// Publication ordering:
-//
-// The write barrier is *pre-publication*, meaning that the write
-// barrier happens prior to the *slot = ptr write that may make ptr
-// reachable by some goroutine that currently cannot reach it.
-//
-//
-// Signal handler pointer writes:
-//
-// In general, the signal handler cannot safely invoke the write
-// barrier because it may run without a P or even during the write
-// barrier.
-//
-// There is exactly one exception: profbuf.go omits a barrier during
-// signal handler profile logging. That's safe only because of the
-// deletion barrier. See profbuf.go for a detailed argument. If we
-// remove the deletion barrier, we'll have to work out a new way to
-// handle the profile logging.
-
-// typedmemmove copies a value of type t to dst from src.
-// Must be nosplit, see #16026.
-//
-// TODO: Perfect for go:nosplitrec since we can't have a safe point
-// anywhere in the bulk barrier or memmove.
-//
-//go:nosplit
-func typedmemmove(typ *_type, dst, src unsafe.Pointer) {
-	if dst == src {
-		return
-	}
-	if writeBarrier.needed && typ.ptrdata != 0 {
-		bulkBarrierPreWrite(uintptr(dst), uintptr(src), typ.ptrdata)
-	}
-	// There's a race here: if some other goroutine can write to
-	// src, it may change some pointer in src after we've
-	// performed the write barrier but before we perform the
-	// memory copy. This safe because the write performed by that
-	// other goroutine must also be accompanied by a write
-	// barrier, so at worst we've unnecessarily greyed the old
-	// pointer that was in src.
-	memmove(dst, src, typ.size)
-	if writeBarrier.cgo {
-		cgoCheckMemmove(typ, dst, src, 0, typ.size)
-	}
-}
-
-//go:linkname reflect_typedmemmove reflect.typedmemmove
-func reflect_typedmemmove(typ *_type, dst, src unsafe.Pointer) {
-	if raceenabled {
-		raceWriteObjectPC(typ, dst, getcallerpc(), abi.FuncPCABIInternal(reflect_typedmemmove))
-		raceReadObjectPC(typ, src, getcallerpc(), abi.FuncPCABIInternal(reflect_typedmemmove))
-	}
-	if msanenabled {
-		msanwrite(dst, typ.size)
-		msanread(src, typ.size)
-	}
-	if asanenabled {
-		asanwrite(dst, typ.size)
-		asanread(src, typ.size)
-	}
-	typedmemmove(typ, dst, src)
-}
-
-//go:linkname reflectlite_typedmemmove internal/reflectlite.typedmemmove
-func reflectlite_typedmemmove(typ *_type, dst, src unsafe.Pointer) {
-	reflect_typedmemmove(typ, dst, src)
-}
-
-// typedmemmovepartial is like typedmemmove but assumes that
-// dst and src point off bytes into the value and only copies size bytes.
-// off must be a multiple of goarch.PtrSize.
-//go:linkname reflect_typedmemmovepartial reflect.typedmemmovepartial
-func reflect_typedmemmovepartial(typ *_type, dst, src unsafe.Pointer, off, size uintptr) {
-	if writeBarrier.needed && typ.ptrdata > off && size >= goarch.PtrSize {
-		if off&(goarch.PtrSize-1) != 0 {
-			panic("reflect: internal error: misaligned offset")
-		}
-		pwsize := alignDown(size, goarch.PtrSize)
-		if poff := typ.ptrdata - off; pwsize > poff {
-			pwsize = poff
-		}
-		bulkBarrierPreWrite(uintptr(dst), uintptr(src), pwsize)
-	}
-
-	memmove(dst, src, size)
-	if writeBarrier.cgo {
-		cgoCheckMemmove(typ, dst, src, off, size)
-	}
-}
-
-// reflectcallmove is invoked by reflectcall to copy the return values
-// out of the stack and into the heap, invoking the necessary write
-// barriers. dst, src, and size describe the return value area to
-// copy. typ describes the entire frame (not just the return values).
-// typ may be nil, which indicates write barriers are not needed.
-//
-// It must be nosplit and must only call nosplit functions because the
-// stack map of reflectcall is wrong.
-//
-//go:nosplit
-func reflectcallmove(typ *_type, dst, src unsafe.Pointer, size uintptr, regs *abi.RegArgs) {
-	if writeBarrier.needed && typ != nil && typ.ptrdata != 0 && size >= goarch.PtrSize {
-		bulkBarrierPreWrite(uintptr(dst), uintptr(src), size)
-	}
-	memmove(dst, src, size)
-
-	// Move pointers returned in registers to a place where the GC can see them.
-	for i := range regs.Ints {
-		if regs.ReturnIsPtr.Get(i) {
-			regs.Ptrs[i] = unsafe.Pointer(regs.Ints[i])
-		}
-	}
-}
-
-//go:nosplit
-func typedslicecopy(typ *_type, dstPtr unsafe.Pointer, dstLen int, srcPtr unsafe.Pointer, srcLen int) int {
-	n := dstLen
-	if n > srcLen {
-		n = srcLen
-	}
-	if n == 0 {
-		return 0
-	}
-
-	// The compiler emits calls to typedslicecopy before
-	// instrumentation runs, so unlike the other copying and
-	// assignment operations, it's not instrumented in the calling
-	// code and needs its own instrumentation.
-	if raceenabled {
-		callerpc := getcallerpc()
-		pc := abi.FuncPCABIInternal(slicecopy)
-		racewriterangepc(dstPtr, uintptr(n)*typ.size, callerpc, pc)
-		racereadrangepc(srcPtr, uintptr(n)*typ.size, callerpc, pc)
-	}
-	if msanenabled {
-		msanwrite(dstPtr, uintptr(n)*typ.size)
-		msanread(srcPtr, uintptr(n)*typ.size)
-	}
-	if asanenabled {
-		asanwrite(dstPtr, uintptr(n)*typ.size)
-		asanread(srcPtr, uintptr(n)*typ.size)
-	}
-
-	if writeBarrier.cgo {
-		cgoCheckSliceCopy(typ, dstPtr, srcPtr, n)
-	}
-
-	if dstPtr == srcPtr {
-		return n
-	}
-
-	// Note: No point in checking typ.ptrdata here:
-	// compiler only emits calls to typedslicecopy for types with pointers,
-	// and growslice and reflect_typedslicecopy check for pointers
-	// before calling typedslicecopy.
-	size := uintptr(n) * typ.size
-	if writeBarrier.needed {
-		pwsize := size - typ.size + typ.ptrdata
-		bulkBarrierPreWrite(uintptr(dstPtr), uintptr(srcPtr), pwsize)
-	}
-	// See typedmemmove for a discussion of the race between the
-	// barrier and memmove.
-	memmove(dstPtr, srcPtr, size)
-	return n
-}
-
-//go:linkname reflect_typedslicecopy reflect.typedslicecopy
-func reflect_typedslicecopy(elemType *_type, dst, src slice) int {
-	if elemType.ptrdata == 0 {
-		return slicecopy(dst.array, dst.len, src.array, src.len, elemType.size)
-	}
-	return typedslicecopy(elemType, dst.array, dst.len, src.array, src.len)
-}
-
-// typedmemclr clears the typed memory at ptr with type typ. The
-// memory at ptr must already be initialized (and hence in type-safe
-// state). If the memory is being initialized for the first time, see
-// memclrNoHeapPointers.
-//
-// If the caller knows that typ has pointers, it can alternatively
-// call memclrHasPointers.
-//
-//go:nosplit
-func typedmemclr(typ *_type, ptr unsafe.Pointer) {
-	if writeBarrier.needed && typ.ptrdata != 0 {
-		bulkBarrierPreWrite(uintptr(ptr), 0, typ.ptrdata)
-	}
-	memclrNoHeapPointers(ptr, typ.size)
-}
-
-//go:linkname reflect_typedmemclr reflect.typedmemclr
-func reflect_typedmemclr(typ *_type, ptr unsafe.Pointer) {
-	typedmemclr(typ, ptr)
-}
-
-//go:linkname reflect_typedmemclrpartial reflect.typedmemclrpartial
-func reflect_typedmemclrpartial(typ *_type, ptr unsafe.Pointer, off, size uintptr) {
-	if writeBarrier.needed && typ.ptrdata != 0 {
-		bulkBarrierPreWrite(uintptr(ptr), 0, size)
-	}
-	memclrNoHeapPointers(ptr, size)
-}
-
-// memclrHasPointers clears n bytes of typed memory starting at ptr.
-// The caller must ensure that the type of the object at ptr has
-// pointers, usually by checking typ.ptrdata. However, ptr
-// does not have to point to the start of the allocation.
-//
-//go:nosplit
-func memclrHasPointers(ptr unsafe.Pointer, n uintptr) {
-	bulkBarrierPreWrite(uintptr(ptr), 0, n)
-	memclrNoHeapPointers(ptr, n)
-}
diff --git a/contrib/go/_std_1.18/src/runtime/mbitmap.go b/contrib/go/_std_1.18/src/runtime/mbitmap.go
deleted file mode 100644
index 937968807b..0000000000
--- a/contrib/go/_std_1.18/src/runtime/mbitmap.go
+++ /dev/null
@@ -1,2043 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Garbage collector: type and heap bitmaps.
-//
-// Stack, data, and bss bitmaps
-//
-// Stack frames and global variables in the data and bss sections are
-// described by bitmaps with 1 bit per pointer-sized word. A "1" bit
-// means the word is a live pointer to be visited by the GC (referred to
-// as "pointer"). A "0" bit means the word should be ignored by GC
-// (referred to as "scalar", though it could be a dead pointer value).
-//
-// Heap bitmap
-//
-// The heap bitmap comprises 2 bits for each pointer-sized word in the heap,
-// stored in the heapArena metadata backing each heap arena.
-// That is, if ha is the heapArena for the arena starting a start,
-// then ha.bitmap[0] holds the 2-bit entries for the four words start
-// through start+3*ptrSize, ha.bitmap[1] holds the entries for
-// start+4*ptrSize through start+7*ptrSize, and so on.
-//
-// In each 2-bit entry, the lower bit is a pointer/scalar bit, just
-// like in the stack/data bitmaps described above. The upper bit
-// indicates scan/dead: a "1" value ("scan") indicates that there may
-// be pointers in later words of the allocation, and a "0" value
-// ("dead") indicates there are no more pointers in the allocation. If
-// the upper bit is 0, the lower bit must also be 0, and this
-// indicates scanning can ignore the rest of the allocation.
-//
-// The 2-bit entries are split when written into the byte, so that the top half
-// of the byte contains 4 high (scan) bits and the bottom half contains 4 low
-// (pointer) bits. This form allows a copy from the 1-bit to the 4-bit form to
-// keep the pointer bits contiguous, instead of having to space them out.
-//
-// The code makes use of the fact that the zero value for a heap
-// bitmap means scalar/dead. This property must be preserved when
-// modifying the encoding.
-//
-// The bitmap for noscan spans is not maintained. Code must ensure
-// that an object is scannable before consulting its bitmap by
-// checking either the noscan bit in the span or by consulting its
-// type's information.
-
-package runtime
-
-import (
-	"internal/goarch"
-	"runtime/internal/atomic"
-	"runtime/internal/sys"
-	"unsafe"
-)
-
-const (
-	bitPointer = 1 << 0
-	bitScan    = 1 << 4
-
-	heapBitsShift      = 1     // shift offset between successive bitPointer or bitScan entries
-	wordsPerBitmapByte = 8 / 2 // heap words described by one bitmap byte
-
-	// all scan/pointer bits in a byte
-	bitScanAll    = bitScan | bitScan<<heapBitsShift | bitScan<<(2*heapBitsShift) | bitScan<<(3*heapBitsShift)
-	bitPointerAll = bitPointer | bitPointer<<heapBitsShift | bitPointer<<(2*heapBitsShift) | bitPointer<<(3*heapBitsShift)
-)
-
-// addb returns the byte pointer p+n.
-//go:nowritebarrier
-//go:nosplit
-func addb(p *byte, n uintptr) *byte {
-	// Note: wrote out full expression instead of calling add(p, n)
-	// to reduce the number of temporaries generated by the
-	// compiler for this trivial expression during inlining.
-	return (*byte)(unsafe.Pointer(uintptr(unsafe.Pointer(p)) + n))
-}
-
-// subtractb returns the byte pointer p-n.
-//go:nowritebarrier
-//go:nosplit
-func subtractb(p *byte, n uintptr) *byte {
-	// Note: wrote out full expression instead of calling add(p, -n)
-	// to reduce the number of temporaries generated by the
-	// compiler for this trivial expression during inlining.
-	return (*byte)(unsafe.Pointer(uintptr(unsafe.Pointer(p)) - n))
-}
-
-// add1 returns the byte pointer p+1.
-//go:nowritebarrier
-//go:nosplit
-func add1(p *byte) *byte {
-	// Note: wrote out full expression instead of calling addb(p, 1)
-	// to reduce the number of temporaries generated by the
-	// compiler for this trivial expression during inlining.
-	return (*byte)(unsafe.Pointer(uintptr(unsafe.Pointer(p)) + 1))
-}
-
-// subtract1 returns the byte pointer p-1.
-//go:nowritebarrier
-//
-// nosplit because it is used during write barriers and must not be preempted.
-//go:nosplit
-func subtract1(p *byte) *byte {
-	// Note: wrote out full expression instead of calling subtractb(p, 1)
-	// to reduce the number of temporaries generated by the
-	// compiler for this trivial expression during inlining.
-	return (*byte)(unsafe.Pointer(uintptr(unsafe.Pointer(p)) - 1))
-}
-
-// heapBits provides access to the bitmap bits for a single heap word.
-// The methods on heapBits take value receivers so that the compiler
-// can more easily inline calls to those methods and registerize the
-// struct fields independently.
-type heapBits struct {
-	bitp  *uint8
-	shift uint32
-	arena uint32 // Index of heap arena containing bitp
-	last  *uint8 // Last byte arena's bitmap
-}
-
-// Make the compiler check that heapBits.arena is large enough to hold
-// the maximum arena frame number.
-var _ = heapBits{arena: (1<<heapAddrBits)/heapArenaBytes - 1}
-
-// markBits provides access to the mark bit for an object in the heap.
-// bytep points to the byte holding the mark bit.
-// mask is a byte with a single bit set that can be &ed with *bytep
-// to see if the bit has been set.
-// *m.byte&m.mask != 0 indicates the mark bit is set.
-// index can be used along with span information to generate
-// the address of the object in the heap.
-// We maintain one set of mark bits for allocation and one for
-// marking purposes.
-type markBits struct {
-	bytep *uint8
-	mask  uint8
-	index uintptr
-}
-
-//go:nosplit
-func (s *mspan) allocBitsForIndex(allocBitIndex uintptr) markBits {
-	bytep, mask := s.allocBits.bitp(allocBitIndex)
-	return markBits{bytep, mask, allocBitIndex}
-}
-
-// refillAllocCache takes 8 bytes s.allocBits starting at whichByte
-// and negates them so that ctz (count trailing zeros) instructions
-// can be used. It then places these 8 bytes into the cached 64 bit
-// s.allocCache.
-func (s *mspan) refillAllocCache(whichByte uintptr) {
-	bytes := (*[8]uint8)(unsafe.Pointer(s.allocBits.bytep(whichByte)))
-	aCache := uint64(0)
-	aCache |= uint64(bytes[0])
-	aCache |= uint64(bytes[1]) << (1 * 8)
-	aCache |= uint64(bytes[2]) << (2 * 8)
-	aCache |= uint64(bytes[3]) << (3 * 8)
-	aCache |= uint64(bytes[4]) << (4 * 8)
-	aCache |= uint64(bytes[5]) << (5 * 8)
-	aCache |= uint64(bytes[6]) << (6 * 8)
-	aCache |= uint64(bytes[7]) << (7 * 8)
-	s.allocCache = ^aCache
-}
-
-// nextFreeIndex returns the index of the next free object in s at
-// or after s.freeindex.
-// There are hardware instructions that can be used to make this
-// faster if profiling warrants it.
-func (s *mspan) nextFreeIndex() uintptr {
-	sfreeindex := s.freeindex
-	snelems := s.nelems
-	if sfreeindex == snelems {
-		return sfreeindex
-	}
-	if sfreeindex > snelems {
-		throw("s.freeindex > s.nelems")
-	}
-
-	aCache := s.allocCache
-
-	bitIndex := sys.Ctz64(aCache)
-	for bitIndex == 64 {
-		// Move index to start of next cached bits.
-		sfreeindex = (sfreeindex + 64) &^ (64 - 1)
-		if sfreeindex >= snelems {
-			s.freeindex = snelems
-			return snelems
-		}
-		whichByte := sfreeindex / 8
-		// Refill s.allocCache with the next 64 alloc bits.
-		s.refillAllocCache(whichByte)
-		aCache = s.allocCache
-		bitIndex = sys.Ctz64(aCache)
-		// nothing available in cached bits
-		// grab the next 8 bytes and try again.
-	}
-	result := sfreeindex + uintptr(bitIndex)
-	if result >= snelems {
-		s.freeindex = snelems
-		return snelems
-	}
-
-	s.allocCache >>= uint(bitIndex + 1)
-	sfreeindex = result + 1
-
-	if sfreeindex%64 == 0 && sfreeindex != snelems {
-		// We just incremented s.freeindex so it isn't 0.
-		// As each 1 in s.allocCache was encountered and used for allocation
-		// it was shifted away. At this point s.allocCache contains all 0s.
-		// Refill s.allocCache so that it corresponds
-		// to the bits at s.allocBits starting at s.freeindex.
-		whichByte := sfreeindex / 8
-		s.refillAllocCache(whichByte)
-	}
-	s.freeindex = sfreeindex
-	return result
-}
-
-// isFree reports whether the index'th object in s is unallocated.
-//
-// The caller must ensure s.state is mSpanInUse, and there must have
-// been no preemption points since ensuring this (which could allow a
-// GC transition, which would allow the state to change).
-func (s *mspan) isFree(index uintptr) bool {
-	if index < s.freeindex {
-		return false
-	}
-	bytep, mask := s.allocBits.bitp(index)
-	return *bytep&mask == 0
-}
-
-// divideByElemSize returns n/s.elemsize.
-// n must be within [0, s.npages*_PageSize),
-// or may be exactly s.npages*_PageSize
-// if s.elemsize is from sizeclasses.go.
-func (s *mspan) divideByElemSize(n uintptr) uintptr {
-	const doubleCheck = false
-
-	// See explanation in mksizeclasses.go's computeDivMagic.
-	q := uintptr((uint64(n) * uint64(s.divMul)) >> 32)
-
-	if doubleCheck && q != n/s.elemsize {
-		println(n, "/", s.elemsize, "should be", n/s.elemsize, "but got", q)
-		throw("bad magic division")
-	}
-	return q
-}
-
-func (s *mspan) objIndex(p uintptr) uintptr {
-	return s.divideByElemSize(p - s.base())
-}
-
-func markBitsForAddr(p uintptr) markBits {
-	s := spanOf(p)
-	objIndex := s.objIndex(p)
-	return s.markBitsForIndex(objIndex)
-}
-
-func (s *mspan) markBitsForIndex(objIndex uintptr) markBits {
-	bytep, mask := s.gcmarkBits.bitp(objIndex)
-	return markBits{bytep, mask, objIndex}
-}
-
-func (s *mspan) markBitsForBase() markBits {
-	return markBits{(*uint8)(s.gcmarkBits), uint8(1), 0}
-}
-
-// isMarked reports whether mark bit m is set.
-func (m markBits) isMarked() bool {
-	return *m.bytep&m.mask != 0
-}
-
-// setMarked sets the marked bit in the markbits, atomically.
-func (m markBits) setMarked() {
-	// Might be racing with other updates, so use atomic update always.
-	// We used to be clever here and use a non-atomic update in certain
-	// cases, but it's not worth the risk.
-	atomic.Or8(m.bytep, m.mask)
-}
-
-// setMarkedNonAtomic sets the marked bit in the markbits, non-atomically.
-func (m markBits) setMarkedNonAtomic() {
-	*m.bytep |= m.mask
-}
-
-// clearMarked clears the marked bit in the markbits, atomically.
-func (m markBits) clearMarked() {
-	// Might be racing with other updates, so use atomic update always.
-	// We used to be clever here and use a non-atomic update in certain
-	// cases, but it's not worth the risk.
-	atomic.And8(m.bytep, ^m.mask)
-}
-
-// markBitsForSpan returns the markBits for the span base address base.
-func markBitsForSpan(base uintptr) (mbits markBits) {
-	mbits = markBitsForAddr(base)
-	if mbits.mask != 1 {
-		throw("markBitsForSpan: unaligned start")
-	}
-	return mbits
-}
-
-// advance advances the markBits to the next object in the span.
-func (m *markBits) advance() {
-	if m.mask == 1<<7 {
-		m.bytep = (*uint8)(unsafe.Pointer(uintptr(unsafe.Pointer(m.bytep)) + 1))
-		m.mask = 1
-	} else {
-		m.mask = m.mask << 1
-	}
-	m.index++
-}
-
-// heapBitsForAddr returns the heapBits for the address addr.
-// The caller must ensure addr is in an allocated span.
-// In particular, be careful not to point past the end of an object.
-//
-// nosplit because it is used during write barriers and must not be preempted.
-//go:nosplit
-func heapBitsForAddr(addr uintptr) (h heapBits) {
-	// 2 bits per word, 4 pairs per byte, and a mask is hard coded.
-	arena := arenaIndex(addr)
-	ha := mheap_.arenas[arena.l1()][arena.l2()]
-	// The compiler uses a load for nil checking ha, but in this
-	// case we'll almost never hit that cache line again, so it
-	// makes more sense to do a value check.
-	if ha == nil {
-		// addr is not in the heap. Return nil heapBits, which
-		// we expect to crash in the caller.
-		return
-	}
-	h.bitp = &ha.bitmap[(addr/(goarch.PtrSize*4))%heapArenaBitmapBytes]
-	h.shift = uint32((addr / goarch.PtrSize) & 3)
-	h.arena = uint32(arena)
-	h.last = &ha.bitmap[len(ha.bitmap)-1]
-	return
-}
-
-// clobberdeadPtr is a special value that is used by the compiler to
-// clobber dead stack slots, when -clobberdead flag is set.
-const clobberdeadPtr = uintptr(0xdeaddead | 0xdeaddead<<((^uintptr(0)>>63)*32))
-
-// badPointer throws bad pointer in heap panic.
-func badPointer(s *mspan, p, refBase, refOff uintptr) {
-	// Typically this indicates an incorrect use
-	// of unsafe or cgo to store a bad pointer in
-	// the Go heap. It may also indicate a runtime
-	// bug.
-	//
-	// TODO(austin): We could be more aggressive
-	// and detect pointers to unallocated objects
-	// in allocated spans.
-	printlock()
-	print("runtime: pointer ", hex(p))
-	if s != nil {
-		state := s.state.get()
-		if state != mSpanInUse {
-			print(" to unallocated span")
-		} else {
-			print(" to unused region of span")
-		}
-		print(" span.base()=", hex(s.base()), " span.limit=", hex(s.limit), " span.state=", state)
-	}
-	print("\n")
-	if refBase != 0 {
-		print("runtime: found in object at *(", hex(refBase), "+", hex(refOff), ")\n")
-		gcDumpObject("object", refBase, refOff)
-	}
-	getg().m.traceback = 2
-	throw("found bad pointer in Go heap (incorrect use of unsafe or cgo?)")
-}
-
-// findObject returns the base address for the heap object containing
-// the address p, the object's span, and the index of the object in s.
-// If p does not point into a heap object, it returns base == 0.
-//
-// If p points is an invalid heap pointer and debug.invalidptr != 0,
-// findObject panics.
-//
-// refBase and refOff optionally give the base address of the object
-// in which the pointer p was found and the byte offset at which it
-// was found. These are used for error reporting.
-//
-// It is nosplit so it is safe for p to be a pointer to the current goroutine's stack.
-// Since p is a uintptr, it would not be adjusted if the stack were to move.
-//go:nosplit
-func findObject(p, refBase, refOff uintptr) (base uintptr, s *mspan, objIndex uintptr) {
-	s = spanOf(p)
-	// If s is nil, the virtual address has never been part of the heap.
-	// This pointer may be to some mmap'd region, so we allow it.
-	if s == nil {
-		if (GOARCH == "amd64" || GOARCH == "arm64") && p == clobberdeadPtr && debug.invalidptr != 0 {
-			// Crash if clobberdeadPtr is seen. Only on AMD64 and ARM64 for now,
-			// as they are the only platform where compiler's clobberdead mode is
-			// implemented. On these platforms clobberdeadPtr cannot be a valid address.
-			badPointer(s, p, refBase, refOff)
-		}
-		return
-	}
-	// If p is a bad pointer, it may not be in s's bounds.
-	//
-	// Check s.state to synchronize with span initialization
-	// before checking other fields. See also spanOfHeap.
-	if state := s.state.get(); state != mSpanInUse || p < s.base() || p >= s.limit {
-		// Pointers into stacks are also ok, the runtime manages these explicitly.
-		if state == mSpanManual {
-			return
-		}
-		// The following ensures that we are rigorous about what data
-		// structures hold valid pointers.
-		if debug.invalidptr != 0 {
-			badPointer(s, p, refBase, refOff)
-		}
-		return
-	}
-
-	objIndex = s.objIndex(p)
-	base = s.base() + objIndex*s.elemsize
-	return
-}
-
-// verifyNotInHeapPtr reports whether converting the not-in-heap pointer into a unsafe.Pointer is ok.
-//go:linkname reflect_verifyNotInHeapPtr reflect.verifyNotInHeapPtr
-func reflect_verifyNotInHeapPtr(p uintptr) bool {
-	// Conversion to a pointer is ok as long as findObject above does not call badPointer.
-	// Since we're already promised that p doesn't point into the heap, just disallow heap
-	// pointers and the special clobbered pointer.
-	return spanOf(p) == nil && p != clobberdeadPtr
-}
-
-// next returns the heapBits describing the next pointer-sized word in memory.
-// That is, if h describes address p, h.next() describes p+ptrSize.
-// Note that next does not modify h. The caller must record the result.
-//
-// nosplit because it is used during write barriers and must not be preempted.
-//go:nosplit
-func (h heapBits) next() heapBits {
-	if h.shift < 3*heapBitsShift {
-		h.shift += heapBitsShift
-	} else if h.bitp != h.last {
-		h.bitp, h.shift = add1(h.bitp), 0
-	} else {
-		// Move to the next arena.
-		return h.nextArena()
-	}
-	return h
-}
-
-// nextArena advances h to the beginning of the next heap arena.
-//
-// This is a slow-path helper to next. gc's inliner knows that
-// heapBits.next can be inlined even though it calls this. This is
-// marked noinline so it doesn't get inlined into next and cause next
-// to be too big to inline.
-//
-//go:nosplit
-//go:noinline
-func (h heapBits) nextArena() heapBits {
-	h.arena++
-	ai := arenaIdx(h.arena)
-	l2 := mheap_.arenas[ai.l1()]
-	if l2 == nil {
-		// We just passed the end of the object, which
-		// was also the end of the heap. Poison h. It
-		// should never be dereferenced at this point.
-		return heapBits{}
-	}
-	ha := l2[ai.l2()]
-	if ha == nil {
-		return heapBits{}
-	}
-	h.bitp, h.shift = &ha.bitmap[0], 0
-	h.last = &ha.bitmap[len(ha.bitmap)-1]
-	return h
-}
-
-// forward returns the heapBits describing n pointer-sized words ahead of h in memory.
-// That is, if h describes address p, h.forward(n) describes p+n*ptrSize.
-// h.forward(1) is equivalent to h.next(), just slower.
-// Note that forward does not modify h. The caller must record the result.
-// bits returns the heap bits for the current word.
-//go:nosplit
-func (h heapBits) forward(n uintptr) heapBits {
-	n += uintptr(h.shift) / heapBitsShift
-	nbitp := uintptr(unsafe.Pointer(h.bitp)) + n/4
-	h.shift = uint32(n%4) * heapBitsShift
-	if nbitp <= uintptr(unsafe.Pointer(h.last)) {
-		h.bitp = (*uint8)(unsafe.Pointer(nbitp))
-		return h
-	}
-
-	// We're in a new heap arena.
-	past := nbitp - (uintptr(unsafe.Pointer(h.last)) + 1)
-	h.arena += 1 + uint32(past/heapArenaBitmapBytes)
-	ai := arenaIdx(h.arena)
-	if l2 := mheap_.arenas[ai.l1()]; l2 != nil && l2[ai.l2()] != nil {
-		a := l2[ai.l2()]
-		h.bitp = &a.bitmap[past%heapArenaBitmapBytes]
-		h.last = &a.bitmap[len(a.bitmap)-1]
-	} else {
-		h.bitp, h.last = nil, nil
-	}
-	return h
-}
-
-// forwardOrBoundary is like forward, but stops at boundaries between
-// contiguous sections of the bitmap. It returns the number of words
-// advanced over, which will be <= n.
-func (h heapBits) forwardOrBoundary(n uintptr) (heapBits, uintptr) {
-	maxn := 4 * ((uintptr(unsafe.Pointer(h.last)) + 1) - uintptr(unsafe.Pointer(h.bitp)))
-	if n > maxn {
-		n = maxn
-	}
-	return h.forward(n), n
-}
-
-// The caller can test morePointers and isPointer by &-ing with bitScan and bitPointer.
-// The result includes in its higher bits the bits for subsequent words
-// described by the same bitmap byte.
-//
-// nosplit because it is used during write barriers and must not be preempted.
-//go:nosplit
-func (h heapBits) bits() uint32 {
-	// The (shift & 31) eliminates a test and conditional branch
-	// from the generated code.
-	return uint32(*h.bitp) >> (h.shift & 31)
-}
-
-// morePointers reports whether this word and all remaining words in this object
-// are scalars.
-// h must not describe the second word of the object.
-func (h heapBits) morePointers() bool {
-	return h.bits()&bitScan != 0
-}
-
-// isPointer reports whether the heap bits describe a pointer word.
-//
-// nosplit because it is used during write barriers and must not be preempted.
-//go:nosplit
-func (h heapBits) isPointer() bool {
-	return h.bits()&bitPointer != 0
-}
-
-// bulkBarrierPreWrite executes a write barrier
-// for every pointer slot in the memory range [src, src+size),
-// using pointer/scalar information from [dst, dst+size).
-// This executes the write barriers necessary before a memmove.
-// src, dst, and size must be pointer-aligned.
-// The range [dst, dst+size) must lie within a single object.
-// It does not perform the actual writes.
-//
-// As a special case, src == 0 indicates that this is being used for a
-// memclr. bulkBarrierPreWrite will pass 0 for the src of each write
-// barrier.
-//
-// Callers should call bulkBarrierPreWrite immediately before
-// calling memmove(dst, src, size). This function is marked nosplit
-// to avoid being preempted; the GC must not stop the goroutine
-// between the memmove and the execution of the barriers.
-// The caller is also responsible for cgo pointer checks if this
-// may be writing Go pointers into non-Go memory.
-//
-// The pointer bitmap is not maintained for allocations containing
-// no pointers at all; any caller of bulkBarrierPreWrite must first
-// make sure the underlying allocation contains pointers, usually
-// by checking typ.ptrdata.
-//
-// Callers must perform cgo checks if writeBarrier.cgo.
-//
-//go:nosplit
-func bulkBarrierPreWrite(dst, src, size uintptr) {
-	if (dst|src|size)&(goarch.PtrSize-1) != 0 {
-		throw("bulkBarrierPreWrite: unaligned arguments")
-	}
-	if !writeBarrier.needed {
-		return
-	}
-	if s := spanOf(dst); s == nil {
-		// If dst is a global, use the data or BSS bitmaps to
-		// execute write barriers.
-		for _, datap := range activeModules() {
-			if datap.data <= dst && dst < datap.edata {
-				bulkBarrierBitmap(dst, src, size, dst-datap.data, datap.gcdatamask.bytedata)
-				return
-			}
-		}
-		for _, datap := range activeModules() {
-			if datap.bss <= dst && dst < datap.ebss {
-				bulkBarrierBitmap(dst, src, size, dst-datap.bss, datap.gcbssmask.bytedata)
-				return
-			}
-		}
-		return
-	} else if s.state.get() != mSpanInUse || dst < s.base() || s.limit <= dst {
-		// dst was heap memory at some point, but isn't now.
-		// It can't be a global. It must be either our stack,
-		// or in the case of direct channel sends, it could be
-		// another stack. Either way, no need for barriers.
-		// This will also catch if dst is in a freed span,
-		// though that should never have.
-		return
-	}
-
-	buf := &getg().m.p.ptr().wbBuf
-	h := heapBitsForAddr(dst)
-	if src == 0 {
-		for i := uintptr(0); i < size; i += goarch.PtrSize {
-			if h.isPointer() {
-				dstx := (*uintptr)(unsafe.Pointer(dst + i))
-				if !buf.putFast(*dstx, 0) {
-					wbBufFlush(nil, 0)
-				}
-			}
-			h = h.next()
-		}
-	} else {
-		for i := uintptr(0); i < size; i += goarch.PtrSize {
-			if h.isPointer() {
-				dstx := (*uintptr)(unsafe.Pointer(dst + i))
-				srcx := (*uintptr)(unsafe.Pointer(src + i))
-				if !buf.putFast(*dstx, *srcx) {
-					wbBufFlush(nil, 0)
-				}
-			}
-			h = h.next()
-		}
-	}
-}
-
-// bulkBarrierPreWriteSrcOnly is like bulkBarrierPreWrite but
-// does not execute write barriers for [dst, dst+size).
-//
-// In addition to the requirements of bulkBarrierPreWrite
-// callers need to ensure [dst, dst+size) is zeroed.
-//
-// This is used for special cases where e.g. dst was just
-// created and zeroed with malloc.
-//go:nosplit
-func bulkBarrierPreWriteSrcOnly(dst, src, size uintptr) {
-	if (dst|src|size)&(goarch.PtrSize-1) != 0 {
-		throw("bulkBarrierPreWrite: unaligned arguments")
-	}
-	if !writeBarrier.needed {
-		return
-	}
-	buf := &getg().m.p.ptr().wbBuf
-	h := heapBitsForAddr(dst)
-	for i := uintptr(0); i < size; i += goarch.PtrSize {
-		if h.isPointer() {
-			srcx := (*uintptr)(unsafe.Pointer(src + i))
-			if !buf.putFast(0, *srcx) {
-				wbBufFlush(nil, 0)
-			}
-		}
-		h = h.next()
-	}
-}
-
-// bulkBarrierBitmap executes write barriers for copying from [src,
-// src+size) to [dst, dst+size) using a 1-bit pointer bitmap. src is
-// assumed to start maskOffset bytes into the data covered by the
-// bitmap in bits (which may not be a multiple of 8).
-//
-// This is used by bulkBarrierPreWrite for writes to data and BSS.
-//
-//go:nosplit
-func bulkBarrierBitmap(dst, src, size, maskOffset uintptr, bits *uint8) {
-	word := maskOffset / goarch.PtrSize
-	bits = addb(bits, word/8)
-	mask := uint8(1) << (word % 8)
-
-	buf := &getg().m.p.ptr().wbBuf
-	for i := uintptr(0); i < size; i += goarch.PtrSize {
-		if mask == 0 {
-			bits = addb(bits, 1)
-			if *bits == 0 {
-				// Skip 8 words.
-				i += 7 * goarch.PtrSize
-				continue
-			}
-			mask = 1
-		}
-		if *bits&mask != 0 {
-			dstx := (*uintptr)(unsafe.Pointer(dst + i))
-			if src == 0 {
-				if !buf.putFast(*dstx, 0) {
-					wbBufFlush(nil, 0)
-				}
-			} else {
-				srcx := (*uintptr)(unsafe.Pointer(src + i))
-				if !buf.putFast(*dstx, *srcx) {
-					wbBufFlush(nil, 0)
-				}
-			}
-		}
-		mask <<= 1
-	}
-}
-
-// typeBitsBulkBarrier executes a write barrier for every
-// pointer that would be copied from [src, src+size) to [dst,
-// dst+size) by a memmove using the type bitmap to locate those
-// pointer slots.
-//
-// The type typ must correspond exactly to [src, src+size) and [dst, dst+size).
-// dst, src, and size must be pointer-aligned.
-// The type typ must have a plain bitmap, not a GC program.
-// The only use of this function is in channel sends, and the
-// 64 kB channel element limit takes care of this for us.
-//
-// Must not be preempted because it typically runs right before memmove,
-// and the GC must observe them as an atomic action.
-//
-// Callers must perform cgo checks if writeBarrier.cgo.
-//
-//go:nosplit
-func typeBitsBulkBarrier(typ *_type, dst, src, size uintptr) {
-	if typ == nil {
-		throw("runtime: typeBitsBulkBarrier without type")
-	}
-	if typ.size != size {
-		println("runtime: typeBitsBulkBarrier with type ", typ.string(), " of size ", typ.size, " but memory size", size)
-		throw("runtime: invalid typeBitsBulkBarrier")
-	}
-	if typ.kind&kindGCProg != 0 {
-		println("runtime: typeBitsBulkBarrier with type ", typ.string(), " with GC prog")
-		throw("runtime: invalid typeBitsBulkBarrier")
-	}
-	if !writeBarrier.needed {
-		return
-	}
-	ptrmask := typ.gcdata
-	buf := &getg().m.p.ptr().wbBuf
-	var bits uint32
-	for i := uintptr(0); i < typ.ptrdata; i += goarch.PtrSize {
-		if i&(goarch.PtrSize*8-1) == 0 {
-			bits = uint32(*ptrmask)
-			ptrmask = addb(ptrmask, 1)
-		} else {
-			bits = bits >> 1
-		}
-		if bits&1 != 0 {
-			dstx := (*uintptr)(unsafe.Pointer(dst + i))
-			srcx := (*uintptr)(unsafe.Pointer(src + i))
-			if !buf.putFast(*dstx, *srcx) {
-				wbBufFlush(nil, 0)
-			}
-		}
-	}
-}
-
-// The methods operating on spans all require that h has been returned
-// by heapBitsForSpan and that size, n, total are the span layout description
-// returned by the mspan's layout method.
-// If total > size*n, it means that there is extra leftover memory in the span,
-// usually due to rounding.
-//
-// TODO(rsc): Perhaps introduce a different heapBitsSpan type.
-
-// initSpan initializes the heap bitmap for a span.
-// If this is a span of pointer-sized objects, it initializes all
-// words to pointer/scan.
-// Otherwise, it initializes all words to scalar/dead.
-func (h heapBits) initSpan(s *mspan) {
-	// Clear bits corresponding to objects.
-	nw := (s.npages << _PageShift) / goarch.PtrSize
-	if nw%wordsPerBitmapByte != 0 {
-		throw("initSpan: unaligned length")
-	}
-	if h.shift != 0 {
-		throw("initSpan: unaligned base")
-	}
-	isPtrs := goarch.PtrSize == 8 && s.elemsize == goarch.PtrSize
-	for nw > 0 {
-		hNext, anw := h.forwardOrBoundary(nw)
-		nbyte := anw / wordsPerBitmapByte
-		if isPtrs {
-			bitp := h.bitp
-			for i := uintptr(0); i < nbyte; i++ {
-				*bitp = bitPointerAll | bitScanAll
-				bitp = add1(bitp)
-			}
-		} else {
-			memclrNoHeapPointers(unsafe.Pointer(h.bitp), nbyte)
-		}
-		h = hNext
-		nw -= anw
-	}
-}
-
-// countAlloc returns the number of objects allocated in span s by
-// scanning the allocation bitmap.
-func (s *mspan) countAlloc() int {
-	count := 0
-	bytes := divRoundUp(s.nelems, 8)
-	// Iterate over each 8-byte chunk and count allocations
-	// with an intrinsic. Note that newMarkBits guarantees that
-	// gcmarkBits will be 8-byte aligned, so we don't have to
-	// worry about edge cases, irrelevant bits will simply be zero.
-	for i := uintptr(0); i < bytes; i += 8 {
-		// Extract 64 bits from the byte pointer and get a OnesCount.
-		// Note that the unsafe cast here doesn't preserve endianness,
-		// but that's OK. We only care about how many bits are 1, not
-		// about the order we discover them in.
-		mrkBits := *(*uint64)(unsafe.Pointer(s.gcmarkBits.bytep(i)))
-		count += sys.OnesCount64(mrkBits)
-	}
-	return count
-}
-
-// heapBitsSetType records that the new allocation [x, x+size)
-// holds in [x, x+dataSize) one or more values of type typ.
-// (The number of values is given by dataSize / typ.size.)
-// If dataSize < size, the fragment [x+dataSize, x+size) is
-// recorded as non-pointer data.
-// It is known that the type has pointers somewhere;
-// malloc does not call heapBitsSetType when there are no pointers,
-// because all free objects are marked as noscan during
-// heapBitsSweepSpan.
-//
-// There can only be one allocation from a given span active at a time,
-// and the bitmap for a span always falls on byte boundaries,
-// so there are no write-write races for access to the heap bitmap.
-// Hence, heapBitsSetType can access the bitmap without atomics.
-//
-// There can be read-write races between heapBitsSetType and things
-// that read the heap bitmap like scanobject. However, since
-// heapBitsSetType is only used for objects that have not yet been
-// made reachable, readers will ignore bits being modified by this
-// function. This does mean this function cannot transiently modify
-// bits that belong to neighboring objects. Also, on weakly-ordered
-// machines, callers must execute a store/store (publication) barrier
-// between calling this function and making the object reachable.
-func heapBitsSetType(x, size, dataSize uintptr, typ *_type) {
-	const doubleCheck = false // slow but helpful; enable to test modifications to this code
-
-	const (
-		mask1 = bitPointer | bitScan                        // 00010001
-		mask2 = bitPointer | bitScan | mask1<<heapBitsShift // 00110011
-		mask3 = bitPointer | bitScan | mask2<<heapBitsShift // 01110111
-	)
-
-	// dataSize is always size rounded up to the next malloc size class,
-	// except in the case of allocating a defer block, in which case
-	// size is sizeof(_defer{}) (at least 6 words) and dataSize may be
-	// arbitrarily larger.
-	//
-	// The checks for size == goarch.PtrSize and size == 2*goarch.PtrSize can therefore
-	// assume that dataSize == size without checking it explicitly.
-
-	if goarch.PtrSize == 8 && size == goarch.PtrSize {
-		// It's one word and it has pointers, it must be a pointer.
-		// Since all allocated one-word objects are pointers
-		// (non-pointers are aggregated into tinySize allocations),
-		// initSpan sets the pointer bits for us. Nothing to do here.
-		if doubleCheck {
-			h := heapBitsForAddr(x)
-			if !h.isPointer() {
-				throw("heapBitsSetType: pointer bit missing")
-			}
-			if !h.morePointers() {
-				throw("heapBitsSetType: scan bit missing")
-			}
-		}
-		return
-	}
-
-	h := heapBitsForAddr(x)
-	ptrmask := typ.gcdata // start of 1-bit pointer mask (or GC program, handled below)
-
-	// 2-word objects only have 4 bitmap bits and 3-word objects only have 6 bitmap bits.
-	// Therefore, these objects share a heap bitmap byte with the objects next to them.
-	// These are called out as a special case primarily so the code below can assume all
-	// objects are at least 4 words long and that their bitmaps start either at the beginning
-	// of a bitmap byte, or half-way in (h.shift of 0 and 2 respectively).
-
-	if size == 2*goarch.PtrSize {
-		if typ.size == goarch.PtrSize {
-			// We're allocating a block big enough to hold two pointers.
-			// On 64-bit, that means the actual object must be two pointers,
-			// or else we'd have used the one-pointer-sized block.
-			// On 32-bit, however, this is the 8-byte block, the smallest one.
-			// So it could be that we're allocating one pointer and this was
-			// just the smallest block available. Distinguish by checking dataSize.
-			// (In general the number of instances of typ being allocated is
-			// dataSize/typ.size.)
-			if goarch.PtrSize == 4 && dataSize == goarch.PtrSize {
-				// 1 pointer object. On 32-bit machines clear the bit for the
-				// unused second word.
-				*h.bitp &^= (bitPointer | bitScan | (bitPointer|bitScan)<<heapBitsShift) << h.shift
-				*h.bitp |= (bitPointer | bitScan) << h.shift
-			} else {
-				// 2-element array of pointer.
-				*h.bitp |= (bitPointer | bitScan | (bitPointer|bitScan)<<heapBitsShift) << h.shift
-			}
-			return
-		}
-		// Otherwise typ.size must be 2*goarch.PtrSize,
-		// and typ.kind&kindGCProg == 0.
-		if doubleCheck {
-			if typ.size != 2*goarch.PtrSize || typ.kind&kindGCProg != 0 {
-				print("runtime: heapBitsSetType size=", size, " but typ.size=", typ.size, " gcprog=", typ.kind&kindGCProg != 0, "\n")
-				throw("heapBitsSetType")
-			}
-		}
-		b := uint32(*ptrmask)
-		hb := b & 3
-		hb |= bitScanAll & ((bitScan << (typ.ptrdata / goarch.PtrSize)) - 1)
-		// Clear the bits for this object so we can set the
-		// appropriate ones.
-		*h.bitp &^= (bitPointer | bitScan | ((bitPointer | bitScan) << heapBitsShift)) << h.shift
-		*h.bitp |= uint8(hb << h.shift)
-		return
-	} else if size == 3*goarch.PtrSize {
-		b := uint8(*ptrmask)
-		if doubleCheck {
-			if b == 0 {
-				println("runtime: invalid type ", typ.string())
-				throw("heapBitsSetType: called with non-pointer type")
-			}
-			if goarch.PtrSize != 8 {
-				throw("heapBitsSetType: unexpected 3 pointer wide size class on 32 bit")
-			}
-			if typ.kind&kindGCProg != 0 {
-				throw("heapBitsSetType: unexpected GC prog for 3 pointer wide size class")
-			}
-			if typ.size == 2*goarch.PtrSize {
-				print("runtime: heapBitsSetType size=", size, " but typ.size=", typ.size, "\n")
-				throw("heapBitsSetType: inconsistent object sizes")
-			}
-		}
-		if typ.size == goarch.PtrSize {
-			// The type contains a pointer otherwise heapBitsSetType wouldn't have been called.
-			// Since the type is only 1 pointer wide and contains a pointer, its gcdata must be exactly 1.
-			if doubleCheck && *typ.gcdata != 1 {
-				print("runtime: heapBitsSetType size=", size, " typ.size=", typ.size, "but *typ.gcdata", *typ.gcdata, "\n")
-				throw("heapBitsSetType: unexpected gcdata for 1 pointer wide type size in 3 pointer wide size class")
-			}
-			// 3 element array of pointers. Unrolling ptrmask 3 times into p yields 00000111.
-			b = 7
-		}
-
-		hb := b & 7
-		// Set bitScan bits for all pointers.
-		hb |= hb << wordsPerBitmapByte
-		// First bitScan bit is always set since the type contains pointers.
-		hb |= bitScan
-		// Second bitScan bit needs to also be set if the third bitScan bit is set.
-		hb |= hb & (bitScan << (2 * heapBitsShift)) >> 1
-
-		// For h.shift > 1 heap bits cross a byte boundary and need to be written part
-		// to h.bitp and part to the next h.bitp.
-		switch h.shift {
-		case 0:
-			*h.bitp &^= mask3 << 0
-			*h.bitp |= hb << 0
-		case 1:
-			*h.bitp &^= mask3 << 1
-			*h.bitp |= hb << 1
-		case 2:
-			*h.bitp &^= mask2 << 2
-			*h.bitp |= (hb & mask2) << 2
-			// Two words written to the first byte.
-			// Advance two words to get to the next byte.
-			h = h.next().next()
-			*h.bitp &^= mask1
-			*h.bitp |= (hb >> 2) & mask1
-		case 3:
-			*h.bitp &^= mask1 << 3
-			*h.bitp |= (hb & mask1) << 3
-			// One word written to the first byte.
-			// Advance one word to get to the next byte.
-			h = h.next()
-			*h.bitp &^= mask2
-			*h.bitp |= (hb >> 1) & mask2
-		}
-		return
-	}
-
-	// Copy from 1-bit ptrmask into 2-bit bitmap.
-	// The basic approach is to use a single uintptr as a bit buffer,
-	// alternating between reloading the buffer and writing bitmap bytes.
-	// In general, one load can supply two bitmap byte writes.
-	// This is a lot of lines of code, but it compiles into relatively few
-	// machine instructions.
-
-	outOfPlace := false
-	if arenaIndex(x+size-1) != arenaIdx(h.arena) || (doubleCheck && fastrandn(2) == 0) {
-		// This object spans heap arenas, so the bitmap may be
-		// discontiguous. Unroll it into the object instead
-		// and then copy it out.
-		//
-		// In doubleCheck mode, we randomly do this anyway to
-		// stress test the bitmap copying path.
-		outOfPlace = true
-		h.bitp = (*uint8)(unsafe.Pointer(x))
-		h.last = nil
-	}
-
-	var (
-		// Ptrmask input.
-		p     *byte   // last ptrmask byte read
-		b     uintptr // ptrmask bits already loaded
-		nb    uintptr // number of bits in b at next read
-		endp  *byte   // final ptrmask byte to read (then repeat)
-		endnb uintptr // number of valid bits in *endp
-		pbits uintptr // alternate source of bits
-
-		// Heap bitmap output.
-		w     uintptr // words processed
-		nw    uintptr // number of words to process
-		hbitp *byte   // next heap bitmap byte to write
-		hb    uintptr // bits being prepared for *hbitp
-	)
-
-	hbitp = h.bitp
-
-	// Handle GC program. Delayed until this part of the code
-	// so that we can use the same double-checking mechanism
-	// as the 1-bit case. Nothing above could have encountered
-	// GC programs: the cases were all too small.
-	if typ.kind&kindGCProg != 0 {
-		heapBitsSetTypeGCProg(h, typ.ptrdata, typ.size, dataSize, size, addb(typ.gcdata, 4))
-		if doubleCheck {
-			// Double-check the heap bits written by GC program
-			// by running the GC program to create a 1-bit pointer mask
-			// and then jumping to the double-check code below.
-			// This doesn't catch bugs shared between the 1-bit and 4-bit
-			// GC program execution, but it does catch mistakes specific
-			// to just one of those and bugs in heapBitsSetTypeGCProg's
-			// implementation of arrays.
-			lock(&debugPtrmask.lock)
-			if debugPtrmask.data == nil {
-				debugPtrmask.data = (*byte)(persistentalloc(1<<20, 1, &memstats.other_sys))
-			}
-			ptrmask = debugPtrmask.data
-			runGCProg(addb(typ.gcdata, 4), nil, ptrmask, 1)
-		}
-		goto Phase4
-	}
-
-	// Note about sizes:
-	//
-	// typ.size is the number of words in the object,
-	// and typ.ptrdata is the number of words in the prefix
-	// of the object that contains pointers. That is, the final
-	// typ.size - typ.ptrdata words contain no pointers.
-	// This allows optimization of a common pattern where
-	// an object has a small header followed by a large scalar
-	// buffer. If we know the pointers are over, we don't have
-	// to scan the buffer's heap bitmap at all.
-	// The 1-bit ptrmasks are sized to contain only bits for
-	// the typ.ptrdata prefix, zero padded out to a full byte
-	// of bitmap. This code sets nw (below) so that heap bitmap
-	// bits are only written for the typ.ptrdata prefix; if there is
-	// more room in the allocated object, the next heap bitmap
-	// entry is a 00, indicating that there are no more pointers
-	// to scan. So only the ptrmask for the ptrdata bytes is needed.
-	//
-	// Replicated copies are not as nice: if there is an array of
-	// objects with scalar tails, all but the last tail does have to
-	// be initialized, because there is no way to say "skip forward".
-	// However, because of the possibility of a repeated type with
-	// size not a multiple of 4 pointers (one heap bitmap byte),
-	// the code already must handle the last ptrmask byte specially
-	// by treating it as containing only the bits for endnb pointers,
-	// where endnb <= 4. We represent large scalar tails that must
-	// be expanded in the replication by setting endnb larger than 4.
-	// This will have the effect of reading many bits out of b,
-	// but once the real bits are shifted out, b will supply as many
-	// zero bits as we try to read, which is exactly what we need.
-
-	p = ptrmask
-	if typ.size < dataSize {
-		// Filling in bits for an array of typ.
-		// Set up for repetition of ptrmask during main loop.
-		// Note that ptrmask describes only a prefix of
-		const maxBits = goarch.PtrSize*8 - 7
-		if typ.ptrdata/goarch.PtrSize <= maxBits {
-			// Entire ptrmask fits in uintptr with room for a byte fragment.
-			// Load into pbits and never read from ptrmask again.
-			// This is especially important when the ptrmask has
-			// fewer than 8 bits in it; otherwise the reload in the middle
-			// of the Phase 2 loop would itself need to loop to gather
-			// at least 8 bits.
-
-			// Accumulate ptrmask into b.
-			// ptrmask is sized to describe only typ.ptrdata, but we record
-			// it as describing typ.size bytes, since all the high bits are zero.
-			nb = typ.ptrdata / goarch.PtrSize
-			for i := uintptr(0); i < nb; i += 8 {
-				b |= uintptr(*p) << i
-				p = add1(p)
-			}
-			nb = typ.size / goarch.PtrSize
-
-			// Replicate ptrmask to fill entire pbits uintptr.
-			// Doubling and truncating is fewer steps than
-			// iterating by nb each time. (nb could be 1.)
-			// Since we loaded typ.ptrdata/goarch.PtrSize bits
-			// but are pretending to have typ.size/goarch.PtrSize,
-			// there might be no replication necessary/possible.
-			pbits = b
-			endnb = nb
-			if nb+nb <= maxBits {
-				for endnb <= goarch.PtrSize*8 {
-					pbits |= pbits << endnb
-					endnb += endnb
-				}
-				// Truncate to a multiple of original ptrmask.
-				// Because nb+nb <= maxBits, nb fits in a byte.
-				// Byte division is cheaper than uintptr division.
-				endnb = uintptr(maxBits/byte(nb)) * nb
-				pbits &= 1<<endnb - 1
-				b = pbits
-				nb = endnb
-			}
-
-			// Clear p and endp as sentinel for using pbits.
-			// Checked during Phase 2 loop.
-			p = nil
-			endp = nil
-		} else {
-			// Ptrmask is larger. Read it multiple times.
-			n := (typ.ptrdata/goarch.PtrSize+7)/8 - 1
-			endp = addb(ptrmask, n)
-			endnb = typ.size/goarch.PtrSize - n*8
-		}
-	}
-	if p != nil {
-		b = uintptr(*p)
-		p = add1(p)
-		nb = 8
-	}
-
-	if typ.size == dataSize {
-		// Single entry: can stop once we reach the non-pointer data.
-		nw = typ.ptrdata / goarch.PtrSize
-	} else {
-		// Repeated instances of typ in an array.
-		// Have to process first N-1 entries in full, but can stop
-		// once we reach the non-pointer data in the final entry.
-		nw = ((dataSize/typ.size-1)*typ.size + typ.ptrdata) / goarch.PtrSize
-	}
-	if nw == 0 {
-		// No pointers! Caller was supposed to check.
-		println("runtime: invalid type ", typ.string())
-		throw("heapBitsSetType: called with non-pointer type")
-		return
-	}
-
-	// Phase 1: Special case for leading byte (shift==0) or half-byte (shift==2).
-	// The leading byte is special because it contains the bits for word 1,
-	// which does not have the scan bit set.
-	// The leading half-byte is special because it's a half a byte,
-	// so we have to be careful with the bits already there.
-	switch {
-	default:
-		throw("heapBitsSetType: unexpected shift")
-
-	case h.shift == 0:
-		// Ptrmask and heap bitmap are aligned.
-		//
-		// This is a fast path for small objects.
-		//
-		// The first byte we write out covers the first four
-		// words of the object. The scan/dead bit on the first
-		// word must be set to scan since there are pointers
-		// somewhere in the object.
-		// In all following words, we set the scan/dead
-		// appropriately to indicate that the object continues
-		// to the next 2-bit entry in the bitmap.
-		//
-		// We set four bits at a time here, but if the object
-		// is fewer than four words, phase 3 will clear
-		// unnecessary bits.
-		hb = b & bitPointerAll
-		hb |= bitScanAll
-		if w += 4; w >= nw {
-			goto Phase3
-		}
-		*hbitp = uint8(hb)
-		hbitp = add1(hbitp)
-		b >>= 4
-		nb -= 4
-
-	case h.shift == 2:
-		// Ptrmask and heap bitmap are misaligned.
-		//
-		// On 32 bit architectures only the 6-word object that corresponds
-		// to a 24 bytes size class can start with h.shift of 2 here since
-		// all other non 16 byte aligned size classes have been handled by
-		// special code paths at the beginning of heapBitsSetType on 32 bit.
-		//
-		// Many size classes are only 16 byte aligned. On 64 bit architectures
-		// this results in a heap bitmap position starting with a h.shift of 2.
-		//
-		// The bits for the first two words are in a byte shared
-		// with another object, so we must be careful with the bits
-		// already there.
-		//
-		// We took care of 1-word, 2-word, and 3-word objects above,
-		// so this is at least a 6-word object.
-		hb = (b & (bitPointer | bitPointer<<heapBitsShift)) << (2 * heapBitsShift)
-		hb |= bitScan << (2 * heapBitsShift)
-		if nw > 1 {
-			hb |= bitScan << (3 * heapBitsShift)
-		}
-		b >>= 2
-		nb -= 2
-		*hbitp &^= uint8((bitPointer | bitScan | ((bitPointer | bitScan) << heapBitsShift)) << (2 * heapBitsShift))
-		*hbitp |= uint8(hb)
-		hbitp = add1(hbitp)
-		if w += 2; w >= nw {
-			// We know that there is more data, because we handled 2-word and 3-word objects above.
-			// This must be at least a 6-word object. If we're out of pointer words,
-			// mark no scan in next bitmap byte and finish.
-			hb = 0
-			w += 4
-			goto Phase3
-		}
-	}
-
-	// Phase 2: Full bytes in bitmap, up to but not including write to last byte (full or partial) in bitmap.
-	// The loop computes the bits for that last write but does not execute the write;
-	// it leaves the bits in hb for processing by phase 3.
-	// To avoid repeated adjustment of nb, we subtract out the 4 bits we're going to
-	// use in the first half of the loop right now, and then we only adjust nb explicitly
-	// if the 8 bits used by each iteration isn't balanced by 8 bits loaded mid-loop.
-	nb -= 4
-	for {
-		// Emit bitmap byte.
-		// b has at least nb+4 bits, with one exception:
-		// if w+4 >= nw, then b has only nw-w bits,
-		// but we'll stop at the break and then truncate
-		// appropriately in Phase 3.
-		hb = b & bitPointerAll
-		hb |= bitScanAll
-		if w += 4; w >= nw {
-			break
-		}
-		*hbitp = uint8(hb)
-		hbitp = add1(hbitp)
-		b >>= 4
-
-		// Load more bits. b has nb right now.
-		if p != endp {
-			// Fast path: keep reading from ptrmask.
-			// nb unmodified: we just loaded 8 bits,
-			// and the next iteration will consume 8 bits,
-			// leaving us with the same nb the next time we're here.
-			if nb < 8 {
-				b |= uintptr(*p) << nb
-				p = add1(p)
-			} else {
-				// Reduce the number of bits in b.
-				// This is important if we skipped
-				// over a scalar tail, since nb could
-				// be larger than the bit width of b.
-				nb -= 8
-			}
-		} else if p == nil {
-			// Almost as fast path: track bit count and refill from pbits.
-			// For short repetitions.
-			if nb < 8 {
-				b |= pbits << nb
-				nb += endnb
-			}
-			nb -= 8 // for next iteration
-		} else {
-			// Slow path: reached end of ptrmask.
-			// Process final partial byte and rewind to start.
-			b |= uintptr(*p) << nb
-			nb += endnb
-			if nb < 8 {
-				b |= uintptr(*ptrmask) << nb
-				p = add1(ptrmask)
-			} else {
-				nb -= 8
-				p = ptrmask
-			}
-		}
-
-		// Emit bitmap byte.
-		hb = b & bitPointerAll
-		hb |= bitScanAll
-		if w += 4; w >= nw {
-			break
-		}
-		*hbitp = uint8(hb)
-		hbitp = add1(hbitp)
-		b >>= 4
-	}
-
-Phase3:
-	// Phase 3: Write last byte or partial byte and zero the rest of the bitmap entries.
-	if w > nw {
-		// Counting the 4 entries in hb not yet written to memory,
-		// there are more entries than possible pointer slots.
-		// Discard the excess entries (can't be more than 3).
-		mask := uintptr(1)<<(4-(w-nw)) - 1
-		hb &= mask | mask<<4 // apply mask to both pointer bits and scan bits
-	}
-
-	// Change nw from counting possibly-pointer words to total words in allocation.
-	nw = size / goarch.PtrSize
-
-	// Write whole bitmap bytes.
-	// The first is hb, the rest are zero.
-	if w <= nw {
-		*hbitp = uint8(hb)
-		hbitp = add1(hbitp)
-		hb = 0 // for possible final half-byte below
-		for w += 4; w <= nw; w += 4 {
-			*hbitp = 0
-			hbitp = add1(hbitp)
-		}
-	}
-
-	// Write final partial bitmap byte if any.
-	// We know w > nw, or else we'd still be in the loop above.
-	// It can be bigger only due to the 4 entries in hb that it counts.
-	// If w == nw+4 then there's nothing left to do: we wrote all nw entries
-	// and can discard the 4 sitting in hb.
-	// But if w == nw+2, we need to write first two in hb.
-	// The byte is shared with the next object, so be careful with
-	// existing bits.
-	if w == nw+2 {
-		*hbitp = *hbitp&^(bitPointer|bitScan|(bitPointer|bitScan)<<heapBitsShift) | uint8(hb)
-	}
-
-Phase4:
-	// Phase 4: Copy unrolled bitmap to per-arena bitmaps, if necessary.
-	if outOfPlace {
-		// TODO: We could probably make this faster by
-		// handling [x+dataSize, x+size) specially.
-		h := heapBitsForAddr(x)
-		// cnw is the number of heap words, or bit pairs
-		// remaining (like nw above).
-		cnw := size / goarch.PtrSize
-		src := (*uint8)(unsafe.Pointer(x))
-		// We know the first and last byte of the bitmap are
-		// not the same, but it's still possible for small
-		// objects span arenas, so it may share bitmap bytes
-		// with neighboring objects.
-		//
-		// Handle the first byte specially if it's shared. See
-		// Phase 1 for why this is the only special case we need.
-		if doubleCheck {
-			if !(h.shift == 0 || h.shift == 2) {
-				print("x=", x, " size=", size, " cnw=", h.shift, "\n")
-				throw("bad start shift")
-			}
-		}
-		if h.shift == 2 {
-			*h.bitp = *h.bitp&^((bitPointer|bitScan|(bitPointer|bitScan)<<heapBitsShift)<<(2*heapBitsShift)) | *src
-			h = h.next().next()
-			cnw -= 2
-			src = addb(src, 1)
-		}
-		// We're now byte aligned. Copy out to per-arena
-		// bitmaps until the last byte (which may again be
-		// partial).
-		for cnw >= 4 {
-			// This loop processes four words at a time,
-			// so round cnw down accordingly.
-			hNext, words := h.forwardOrBoundary(cnw / 4 * 4)
-
-			// n is the number of bitmap bytes to copy.
-			n := words / 4
-			memmove(unsafe.Pointer(h.bitp), unsafe.Pointer(src), n)
-			cnw -= words
-			h = hNext
-			src = addb(src, n)
-		}
-		if doubleCheck && h.shift != 0 {
-			print("cnw=", cnw, " h.shift=", h.shift, "\n")
-			throw("bad shift after block copy")
-		}
-		// Handle the last byte if it's shared.
-		if cnw == 2 {
-			*h.bitp = *h.bitp&^(bitPointer|bitScan|(bitPointer|bitScan)<<heapBitsShift) | *src
-			src = addb(src, 1)
-			h = h.next().next()
-		}
-		if doubleCheck {
-			if uintptr(unsafe.Pointer(src)) > x+size {
-				throw("copy exceeded object size")
-			}
-			if !(cnw == 0 || cnw == 2) {
-				print("x=", x, " size=", size, " cnw=", cnw, "\n")
-				throw("bad number of remaining words")
-			}
-			// Set up hbitp so doubleCheck code below can check it.
-			hbitp = h.bitp
-		}
-		// Zero the object where we wrote the bitmap.
-		memclrNoHeapPointers(unsafe.Pointer(x), uintptr(unsafe.Pointer(src))-x)
-	}
-
-	// Double check the whole bitmap.
-	if doubleCheck {
-		// x+size may not point to the heap, so back up one
-		// word and then advance it the way we do above.
-		end := heapBitsForAddr(x + size - goarch.PtrSize)
-		if outOfPlace {
-			// In out-of-place copying, we just advance
-			// using next.
-			end = end.next()
-		} else {
-			// Don't use next because that may advance to
-			// the next arena and the in-place logic
-			// doesn't do that.
-			end.shift += heapBitsShift
-			if end.shift == 4*heapBitsShift {
-				end.bitp, end.shift = add1(end.bitp), 0
-			}
-		}
-		if typ.kind&kindGCProg == 0 && (hbitp != end.bitp || (w == nw+2) != (end.shift == 2)) {
-			println("ended at wrong bitmap byte for", typ.string(), "x", dataSize/typ.size)
-			print("typ.size=", typ.size, " typ.ptrdata=", typ.ptrdata, " dataSize=", dataSize, " size=", size, "\n")
-			print("w=", w, " nw=", nw, " b=", hex(b), " nb=", nb, " hb=", hex(hb), "\n")
-			h0 := heapBitsForAddr(x)
-			print("initial bits h0.bitp=", h0.bitp, " h0.shift=", h0.shift, "\n")
-			print("ended at hbitp=", hbitp, " but next starts at bitp=", end.bitp, " shift=", end.shift, "\n")
-			throw("bad heapBitsSetType")
-		}
-
-		// Double-check that bits to be written were written correctly.
-		// Does not check that other bits were not written, unfortunately.
-		h := heapBitsForAddr(x)
-		nptr := typ.ptrdata / goarch.PtrSize
-		ndata := typ.size / goarch.PtrSize
-		count := dataSize / typ.size
-		totalptr := ((count-1)*typ.size + typ.ptrdata) / goarch.PtrSize
-		for i := uintptr(0); i < size/goarch.PtrSize; i++ {
-			j := i % ndata
-			var have, want uint8
-			have = (*h.bitp >> h.shift) & (bitPointer | bitScan)
-			if i >= totalptr {
-				if typ.kind&kindGCProg != 0 && i < (totalptr+3)/4*4 {
-					// heapBitsSetTypeGCProg always fills
-					// in full nibbles of bitScan.
-					want = bitScan
-				}
-			} else {
-				if j < nptr && (*addb(ptrmask, j/8)>>(j%8))&1 != 0 {
-					want |= bitPointer
-				}
-				want |= bitScan
-			}
-			if have != want {
-				println("mismatch writing bits for", typ.string(), "x", dataSize/typ.size)
-				print("typ.size=", typ.size, " typ.ptrdata=", typ.ptrdata, " dataSize=", dataSize, " size=", size, "\n")
-				print("kindGCProg=", typ.kind&kindGCProg != 0, " outOfPlace=", outOfPlace, "\n")
-				print("w=", w, " nw=", nw, " b=", hex(b), " nb=", nb, " hb=", hex(hb), "\n")
-				h0 := heapBitsForAddr(x)
-				print("initial bits h0.bitp=", h0.bitp, " h0.shift=", h0.shift, "\n")
-				print("current bits h.bitp=", h.bitp, " h.shift=", h.shift, " *h.bitp=", hex(*h.bitp), "\n")
-				print("ptrmask=", ptrmask, " p=", p, " endp=", endp, " endnb=", endnb, " pbits=", hex(pbits), " b=", hex(b), " nb=", nb, "\n")
-				println("at word", i, "offset", i*goarch.PtrSize, "have", hex(have), "want", hex(want))
-				if typ.kind&kindGCProg != 0 {
-					println("GC program:")
-					dumpGCProg(addb(typ.gcdata, 4))
-				}
-				throw("bad heapBitsSetType")
-			}
-			h = h.next()
-		}
-		if ptrmask == debugPtrmask.data {
-			unlock(&debugPtrmask.lock)
-		}
-	}
-}
-
-var debugPtrmask struct {
-	lock mutex
-	data *byte
-}
-
-// heapBitsSetTypeGCProg implements heapBitsSetType using a GC program.
-// progSize is the size of the memory described by the program.
-// elemSize is the size of the element that the GC program describes (a prefix of).
-// dataSize is the total size of the intended data, a multiple of elemSize.
-// allocSize is the total size of the allocated memory.
-//
-// GC programs are only used for large allocations.
-// heapBitsSetType requires that allocSize is a multiple of 4 words,
-// so that the relevant bitmap bytes are not shared with surrounding
-// objects.
-func heapBitsSetTypeGCProg(h heapBits, progSize, elemSize, dataSize, allocSize uintptr, prog *byte) {
-	if goarch.PtrSize == 8 && allocSize%(4*goarch.PtrSize) != 0 {
-		// Alignment will be wrong.
-		throw("heapBitsSetTypeGCProg: small allocation")
-	}
-	var totalBits uintptr
-	if elemSize == dataSize {
-		totalBits = runGCProg(prog, nil, h.bitp, 2)
-		if totalBits*goarch.PtrSize != progSize {
-			println("runtime: heapBitsSetTypeGCProg: total bits", totalBits, "but progSize", progSize)
-			throw("heapBitsSetTypeGCProg: unexpected bit count")
-		}
-	} else {
-		count := dataSize / elemSize
-
-		// Piece together program trailer to run after prog that does:
-		//	literal(0)
-		//	repeat(1, elemSize-progSize-1) // zeros to fill element size
-		//	repeat(elemSize, count-1) // repeat that element for count
-		// This zero-pads the data remaining in the first element and then
-		// repeats that first element to fill the array.
-		var trailer [40]byte // 3 varints (max 10 each) + some bytes
-		i := 0
-		if n := elemSize/goarch.PtrSize - progSize/goarch.PtrSize; n > 0 {
-			// literal(0)
-			trailer[i] = 0x01
-			i++
-			trailer[i] = 0
-			i++
-			if n > 1 {
-				// repeat(1, n-1)
-				trailer[i] = 0x81
-				i++
-				n--
-				for ; n >= 0x80; n >>= 7 {
-					trailer[i] = byte(n | 0x80)
-					i++
-				}
-				trailer[i] = byte(n)
-				i++
-			}
-		}
-		// repeat(elemSize/ptrSize, count-1)
-		trailer[i] = 0x80
-		i++
-		n := elemSize / goarch.PtrSize
-		for ; n >= 0x80; n >>= 7 {
-			trailer[i] = byte(n | 0x80)
-			i++
-		}
-		trailer[i] = byte(n)
-		i++
-		n = count - 1
-		for ; n >= 0x80; n >>= 7 {
-			trailer[i] = byte(n | 0x80)
-			i++
-		}
-		trailer[i] = byte(n)
-		i++
-		trailer[i] = 0
-		i++
-
-		runGCProg(prog, &trailer[0], h.bitp, 2)
-
-		// Even though we filled in the full array just now,
-		// record that we only filled in up to the ptrdata of the
-		// last element. This will cause the code below to
-		// memclr the dead section of the final array element,
-		// so that scanobject can stop early in the final element.
-		totalBits = (elemSize*(count-1) + progSize) / goarch.PtrSize
-	}
-	endProg := unsafe.Pointer(addb(h.bitp, (totalBits+3)/4))
-	endAlloc := unsafe.Pointer(addb(h.bitp, allocSize/goarch.PtrSize/wordsPerBitmapByte))
-	memclrNoHeapPointers(endProg, uintptr(endAlloc)-uintptr(endProg))
-}
-
-// progToPointerMask returns the 1-bit pointer mask output by the GC program prog.
-// size the size of the region described by prog, in bytes.
-// The resulting bitvector will have no more than size/goarch.PtrSize bits.
-func progToPointerMask(prog *byte, size uintptr) bitvector {
-	n := (size/goarch.PtrSize + 7) / 8
-	x := (*[1 << 30]byte)(persistentalloc(n+1, 1, &memstats.buckhash_sys))[:n+1]
-	x[len(x)-1] = 0xa1 // overflow check sentinel
-	n = runGCProg(prog, nil, &x[0], 1)
-	if x[len(x)-1] != 0xa1 {
-		throw("progToPointerMask: overflow")
-	}
-	return bitvector{int32(n), &x[0]}
-}
-
-// Packed GC pointer bitmaps, aka GC programs.
-//
-// For large types containing arrays, the type information has a
-// natural repetition that can be encoded to save space in the
-// binary and in the memory representation of the type information.
-//
-// The encoding is a simple Lempel-Ziv style bytecode machine
-// with the following instructions:
-//
-//	00000000: stop
-//	0nnnnnnn: emit n bits copied from the next (n+7)/8 bytes
-//	10000000 n c: repeat the previous n bits c times; n, c are varints
-//	1nnnnnnn c: repeat the previous n bits c times; c is a varint
-
-// runGCProg executes the GC program prog, and then trailer if non-nil,
-// writing to dst with entries of the given size.
-// If size == 1, dst is a 1-bit pointer mask laid out moving forward from dst.
-// If size == 2, dst is the 2-bit heap bitmap, and writes move backward
-// starting at dst (because the heap bitmap does). In this case, the caller guarantees
-// that only whole bytes in dst need to be written.
-//
-// runGCProg returns the number of 1- or 2-bit entries written to memory.
-func runGCProg(prog, trailer, dst *byte, size int) uintptr {
-	dstStart := dst
-
-	// Bits waiting to be written to memory.
-	var bits uintptr
-	var nbits uintptr
-
-	p := prog
-Run:
-	for {
-		// Flush accumulated full bytes.
-		// The rest of the loop assumes that nbits <= 7.
-		for ; nbits >= 8; nbits -= 8 {
-			if size == 1 {
-				*dst = uint8(bits)
-				dst = add1(dst)
-				bits >>= 8
-			} else {
-				v := bits&bitPointerAll | bitScanAll
-				*dst = uint8(v)
-				dst = add1(dst)
-				bits >>= 4
-				v = bits&bitPointerAll | bitScanAll
-				*dst = uint8(v)
-				dst = add1(dst)
-				bits >>= 4
-			}
-		}
-
-		// Process one instruction.
-		inst := uintptr(*p)
-		p = add1(p)
-		n := inst & 0x7F
-		if inst&0x80 == 0 {
-			// Literal bits; n == 0 means end of program.
-			if n == 0 {
-				// Program is over; continue in trailer if present.
-				if trailer != nil {
-					p = trailer
-					trailer = nil
-					continue
-				}
-				break Run
-			}
-			nbyte := n / 8
-			for i := uintptr(0); i < nbyte; i++ {
-				bits |= uintptr(*p) << nbits
-				p = add1(p)
-				if size == 1 {
-					*dst = uint8(bits)
-					dst = add1(dst)
-					bits >>= 8
-				} else {
-					v := bits&0xf | bitScanAll
-					*dst = uint8(v)
-					dst = add1(dst)
-					bits >>= 4
-					v = bits&0xf | bitScanAll
-					*dst = uint8(v)
-					dst = add1(dst)
-					bits >>= 4
-				}
-			}
-			if n %= 8; n > 0 {
-				bits |= uintptr(*p) << nbits
-				p = add1(p)
-				nbits += n
-			}
-			continue Run
-		}
-
-		// Repeat. If n == 0, it is encoded in a varint in the next bytes.
-		if n == 0 {
-			for off := uint(0); ; off += 7 {
-				x := uintptr(*p)
-				p = add1(p)
-				n |= (x & 0x7F) << off
-				if x&0x80 == 0 {
-					break
-				}
-			}
-		}
-
-		// Count is encoded in a varint in the next bytes.
-		c := uintptr(0)
-		for off := uint(0); ; off += 7 {
-			x := uintptr(*p)
-			p = add1(p)
-			c |= (x & 0x7F) << off
-			if x&0x80 == 0 {
-				break
-			}
-		}
-		c *= n // now total number of bits to copy
-
-		// If the number of bits being repeated is small, load them
-		// into a register and use that register for the entire loop
-		// instead of repeatedly reading from memory.
-		// Handling fewer than 8 bits here makes the general loop simpler.
-		// The cutoff is goarch.PtrSize*8 - 7 to guarantee that when we add
-		// the pattern to a bit buffer holding at most 7 bits (a partial byte)
-		// it will not overflow.
-		src := dst
-		const maxBits = goarch.PtrSize*8 - 7
-		if n <= maxBits {
-			// Start with bits in output buffer.
-			pattern := bits
-			npattern := nbits
-
-			// If we need more bits, fetch them from memory.
-			if size == 1 {
-				src = subtract1(src)
-				for npattern < n {
-					pattern <<= 8
-					pattern |= uintptr(*src)
-					src = subtract1(src)
-					npattern += 8
-				}
-			} else {
-				src = subtract1(src)
-				for npattern < n {
-					pattern <<= 4
-					pattern |= uintptr(*src) & 0xf
-					src = subtract1(src)
-					npattern += 4
-				}
-			}
-
-			// We started with the whole bit output buffer,
-			// and then we loaded bits from whole bytes.
-			// Either way, we might now have too many instead of too few.
-			// Discard the extra.
-			if npattern > n {
-				pattern >>= npattern - n
-				npattern = n
-			}
-
-			// Replicate pattern to at most maxBits.
-			if npattern == 1 {
-				// One bit being repeated.
-				// If the bit is 1, make the pattern all 1s.
-				// If the bit is 0, the pattern is already all 0s,
-				// but we can claim that the number of bits
-				// in the word is equal to the number we need (c),
-				// because right shift of bits will zero fill.
-				if pattern == 1 {
-					pattern = 1<<maxBits - 1
-					npattern = maxBits
-				} else {
-					npattern = c
-				}
-			} else {
-				b := pattern
-				nb := npattern
-				if nb+nb <= maxBits {
-					// Double pattern until the whole uintptr is filled.
-					for nb <= goarch.PtrSize*8 {
-						b |= b << nb
-						nb += nb
-					}
-					// Trim away incomplete copy of original pattern in high bits.
-					// TODO(rsc): Replace with table lookup or loop on systems without divide?
-					nb = maxBits / npattern * npattern
-					b &= 1<<nb - 1
-					pattern = b
-					npattern = nb
-				}
-			}
-
-			// Add pattern to bit buffer and flush bit buffer, c/npattern times.
-			// Since pattern contains >8 bits, there will be full bytes to flush
-			// on each iteration.
-			for ; c >= npattern; c -= npattern {
-				bits |= pattern << nbits
-				nbits += npattern
-				if size == 1 {
-					for nbits >= 8 {
-						*dst = uint8(bits)
-						dst = add1(dst)
-						bits >>= 8
-						nbits -= 8
-					}
-				} else {
-					for nbits >= 4 {
-						*dst = uint8(bits&0xf | bitScanAll)
-						dst = add1(dst)
-						bits >>= 4
-						nbits -= 4
-					}
-				}
-			}
-
-			// Add final fragment to bit buffer.
-			if c > 0 {
-				pattern &= 1<<c - 1
-				bits |= pattern << nbits
-				nbits += c
-			}
-			continue Run
-		}
-
-		// Repeat; n too large to fit in a register.
-		// Since nbits <= 7, we know the first few bytes of repeated data
-		// are already written to memory.
-		off := n - nbits // n > nbits because n > maxBits and nbits <= 7
-		if size == 1 {
-			// Leading src fragment.
-			src = subtractb(src, (off+7)/8)
-			if frag := off & 7; frag != 0 {
-				bits |= uintptr(*src) >> (8 - frag) << nbits
-				src = add1(src)
-				nbits += frag
-				c -= frag
-			}
-			// Main loop: load one byte, write another.
-			// The bits are rotating through the bit buffer.
-			for i := c / 8; i > 0; i-- {
-				bits |= uintptr(*src) << nbits
-				src = add1(src)
-				*dst = uint8(bits)
-				dst = add1(dst)
-				bits >>= 8
-			}
-			// Final src fragment.
-			if c %= 8; c > 0 {
-				bits |= (uintptr(*src) & (1<<c - 1)) << nbits
-				nbits += c
-			}
-		} else {
-			// Leading src fragment.
-			src = subtractb(src, (off+3)/4)
-			if frag := off & 3; frag != 0 {
-				bits |= (uintptr(*src) & 0xf) >> (4 - frag) << nbits
-				src = add1(src)
-				nbits += frag
-				c -= frag
-			}
-			// Main loop: load one byte, write another.
-			// The bits are rotating through the bit buffer.
-			for i := c / 4; i > 0; i-- {
-				bits |= (uintptr(*src) & 0xf) << nbits
-				src = add1(src)
-				*dst = uint8(bits&0xf | bitScanAll)
-				dst = add1(dst)
-				bits >>= 4
-			}
-			// Final src fragment.
-			if c %= 4; c > 0 {
-				bits |= (uintptr(*src) & (1<<c - 1)) << nbits
-				nbits += c
-			}
-		}
-	}
-
-	// Write any final bits out, using full-byte writes, even for the final byte.
-	var totalBits uintptr
-	if size == 1 {
-		totalBits = (uintptr(unsafe.Pointer(dst))-uintptr(unsafe.Pointer(dstStart)))*8 + nbits
-		nbits += -nbits & 7
-		for ; nbits > 0; nbits -= 8 {
-			*dst = uint8(bits)
-			dst = add1(dst)
-			bits >>= 8
-		}
-	} else {
-		totalBits = (uintptr(unsafe.Pointer(dst))-uintptr(unsafe.Pointer(dstStart)))*4 + nbits
-		nbits += -nbits & 3
-		for ; nbits > 0; nbits -= 4 {
-			v := bits&0xf | bitScanAll
-			*dst = uint8(v)
-			dst = add1(dst)
-			bits >>= 4
-		}
-	}
-	return totalBits
-}
-
-// materializeGCProg allocates space for the (1-bit) pointer bitmask
-// for an object of size ptrdata.  Then it fills that space with the
-// pointer bitmask specified by the program prog.
-// The bitmask starts at s.startAddr.
-// The result must be deallocated with dematerializeGCProg.
-func materializeGCProg(ptrdata uintptr, prog *byte) *mspan {
-	// Each word of ptrdata needs one bit in the bitmap.
-	bitmapBytes := divRoundUp(ptrdata, 8*goarch.PtrSize)
-	// Compute the number of pages needed for bitmapBytes.
-	pages := divRoundUp(bitmapBytes, pageSize)
-	s := mheap_.allocManual(pages, spanAllocPtrScalarBits)
-	runGCProg(addb(prog, 4), nil, (*byte)(unsafe.Pointer(s.startAddr)), 1)
-	return s
-}
-func dematerializeGCProg(s *mspan) {
-	mheap_.freeManual(s, spanAllocPtrScalarBits)
-}
-
-func dumpGCProg(p *byte) {
-	nptr := 0
-	for {
-		x := *p
-		p = add1(p)
-		if x == 0 {
-			print("\t", nptr, " end\n")
-			break
-		}
-		if x&0x80 == 0 {
-			print("\t", nptr, " lit ", x, ":")
-			n := int(x+7) / 8
-			for i := 0; i < n; i++ {
-				print(" ", hex(*p))
-				p = add1(p)
-			}
-			print("\n")
-			nptr += int(x)
-		} else {
-			nbit := int(x &^ 0x80)
-			if nbit == 0 {
-				for nb := uint(0); ; nb += 7 {
-					x := *p
-					p = add1(p)
-					nbit |= int(x&0x7f) << nb
-					if x&0x80 == 0 {
-						break
-					}
-				}
-			}
-			count := 0
-			for nb := uint(0); ; nb += 7 {
-				x := *p
-				p = add1(p)
-				count |= int(x&0x7f) << nb
-				if x&0x80 == 0 {
-					break
-				}
-			}
-			print("\t", nptr, " repeat ", nbit, " × ", count, "\n")
-			nptr += nbit * count
-		}
-	}
-}
-
-// Testing.
-
-func getgcmaskcb(frame *stkframe, ctxt unsafe.Pointer) bool {
-	target := (*stkframe)(ctxt)
-	if frame.sp <= target.sp && target.sp < frame.varp {
-		*target = *frame
-		return false
-	}
-	return true
-}
-
-// gcbits returns the GC type info for x, for testing.
-// The result is the bitmap entries (0 or 1), one entry per byte.
-//go:linkname reflect_gcbits reflect.gcbits
-func reflect_gcbits(x any) []byte {
-	ret := getgcmask(x)
-	typ := (*ptrtype)(unsafe.Pointer(efaceOf(&x)._type)).elem
-	nptr := typ.ptrdata / goarch.PtrSize
-	for uintptr(len(ret)) > nptr && ret[len(ret)-1] == 0 {
-		ret = ret[:len(ret)-1]
-	}
-	return ret
-}
-
-// Returns GC type info for the pointer stored in ep for testing.
-// If ep points to the stack, only static live information will be returned
-// (i.e. not for objects which are only dynamically live stack objects).
-func getgcmask(ep any) (mask []byte) {
-	e := *efaceOf(&ep)
-	p := e.data
-	t := e._type
-	// data or bss
-	for _, datap := range activeModules() {
-		// data
-		if datap.data <= uintptr(p) && uintptr(p) < datap.edata {
-			bitmap := datap.gcdatamask.bytedata
-			n := (*ptrtype)(unsafe.Pointer(t)).elem.size
-			mask = make([]byte, n/goarch.PtrSize)
-			for i := uintptr(0); i < n; i += goarch.PtrSize {
-				off := (uintptr(p) + i - datap.data) / goarch.PtrSize
-				mask[i/goarch.PtrSize] = (*addb(bitmap, off/8) >> (off % 8)) & 1
-			}
-			return
-		}
-
-		// bss
-		if datap.bss <= uintptr(p) && uintptr(p) < datap.ebss {
-			bitmap := datap.gcbssmask.bytedata
-			n := (*ptrtype)(unsafe.Pointer(t)).elem.size
-			mask = make([]byte, n/goarch.PtrSize)
-			for i := uintptr(0); i < n; i += goarch.PtrSize {
-				off := (uintptr(p) + i - datap.bss) / goarch.PtrSize
-				mask[i/goarch.PtrSize] = (*addb(bitmap, off/8) >> (off % 8)) & 1
-			}
-			return
-		}
-	}
-
-	// heap
-	if base, s, _ := findObject(uintptr(p), 0, 0); base != 0 {
-		hbits := heapBitsForAddr(base)
-		n := s.elemsize
-		mask = make([]byte, n/goarch.PtrSize)
-		for i := uintptr(0); i < n; i += goarch.PtrSize {
-			if hbits.isPointer() {
-				mask[i/goarch.PtrSize] = 1
-			}
-			if !hbits.morePointers() {
-				mask = mask[:i/goarch.PtrSize]
-				break
-			}
-			hbits = hbits.next()
-		}
-		return
-	}
-
-	// stack
-	if _g_ := getg(); _g_.m.curg.stack.lo <= uintptr(p) && uintptr(p) < _g_.m.curg.stack.hi {
-		var frame stkframe
-		frame.sp = uintptr(p)
-		_g_ := getg()
-		gentraceback(_g_.m.curg.sched.pc, _g_.m.curg.sched.sp, 0, _g_.m.curg, 0, nil, 1000, getgcmaskcb, noescape(unsafe.Pointer(&frame)), 0)
-		if frame.fn.valid() {
-			locals, _, _ := getStackMap(&frame, nil, false)
-			if locals.n == 0 {
-				return
-			}
-			size := uintptr(locals.n) * goarch.PtrSize
-			n := (*ptrtype)(unsafe.Pointer(t)).elem.size
-			mask = make([]byte, n/goarch.PtrSize)
-			for i := uintptr(0); i < n; i += goarch.PtrSize {
-				off := (uintptr(p) + i - frame.varp + size) / goarch.PtrSize
-				mask[i/goarch.PtrSize] = locals.ptrbit(off)
-			}
-		}
-		return
-	}
-
-	// otherwise, not something the GC knows about.
-	// possibly read-only data, like malloc(0).
-	// must not have pointers
-	return
-}
diff --git a/contrib/go/_std_1.18/src/runtime/mcache.go b/contrib/go/_std_1.18/src/runtime/mcache.go
deleted file mode 100644
index c58e05dd29..0000000000
--- a/contrib/go/_std_1.18/src/runtime/mcache.go
+++ /dev/null
@@ -1,298 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"runtime/internal/atomic"
-	"unsafe"
-)
-
-// Per-thread (in Go, per-P) cache for small objects.
-// This includes a small object cache and local allocation stats.
-// No locking needed because it is per-thread (per-P).
-//
-// mcaches are allocated from non-GC'd memory, so any heap pointers
-// must be specially handled.
-//
-//go:notinheap
-type mcache struct {
-	// The following members are accessed on every malloc,
-	// so they are grouped here for better caching.
-	nextSample uintptr // trigger heap sample after allocating this many bytes
-	scanAlloc  uintptr // bytes of scannable heap allocated
-
-	// Allocator cache for tiny objects w/o pointers.
-	// See "Tiny allocator" comment in malloc.go.
-
-	// tiny points to the beginning of the current tiny block, or
-	// nil if there is no current tiny block.
-	//
-	// tiny is a heap pointer. Since mcache is in non-GC'd memory,
-	// we handle it by clearing it in releaseAll during mark
-	// termination.
-	//
-	// tinyAllocs is the number of tiny allocations performed
-	// by the P that owns this mcache.
-	tiny       uintptr
-	tinyoffset uintptr
-	tinyAllocs uintptr
-
-	// The rest is not accessed on every malloc.
-
-	alloc [numSpanClasses]*mspan // spans to allocate from, indexed by spanClass
-
-	stackcache [_NumStackOrders]stackfreelist
-
-	// flushGen indicates the sweepgen during which this mcache
-	// was last flushed. If flushGen != mheap_.sweepgen, the spans
-	// in this mcache are stale and need to the flushed so they
-	// can be swept. This is done in acquirep.
-	flushGen uint32
-}
-
-// A gclink is a node in a linked list of blocks, like mlink,
-// but it is opaque to the garbage collector.
-// The GC does not trace the pointers during collection,
-// and the compiler does not emit write barriers for assignments
-// of gclinkptr values. Code should store references to gclinks
-// as gclinkptr, not as *gclink.
-type gclink struct {
-	next gclinkptr
-}
-
-// A gclinkptr is a pointer to a gclink, but it is opaque
-// to the garbage collector.
-type gclinkptr uintptr
-
-// ptr returns the *gclink form of p.
-// The result should be used for accessing fields, not stored
-// in other data structures.
-func (p gclinkptr) ptr() *gclink {
-	return (*gclink)(unsafe.Pointer(p))
-}
-
-type stackfreelist struct {
-	list gclinkptr // linked list of free stacks
-	size uintptr   // total size of stacks in list
-}
-
-// dummy mspan that contains no free objects.
-var emptymspan mspan
-
-func allocmcache() *mcache {
-	var c *mcache
-	systemstack(func() {
-		lock(&mheap_.lock)
-		c = (*mcache)(mheap_.cachealloc.alloc())
-		c.flushGen = mheap_.sweepgen
-		unlock(&mheap_.lock)
-	})
-	for i := range c.alloc {
-		c.alloc[i] = &emptymspan
-	}
-	c.nextSample = nextSample()
-	return c
-}
-
-// freemcache releases resources associated with this
-// mcache and puts the object onto a free list.
-//
-// In some cases there is no way to simply release
-// resources, such as statistics, so donate them to
-// a different mcache (the recipient).
-func freemcache(c *mcache) {
-	systemstack(func() {
-		c.releaseAll()
-		stackcache_clear(c)
-
-		// NOTE(rsc,rlh): If gcworkbuffree comes back, we need to coordinate
-		// with the stealing of gcworkbufs during garbage collection to avoid
-		// a race where the workbuf is double-freed.
-		// gcworkbuffree(c.gcworkbuf)
-
-		lock(&mheap_.lock)
-		mheap_.cachealloc.free(unsafe.Pointer(c))
-		unlock(&mheap_.lock)
-	})
-}
-
-// getMCache is a convenience function which tries to obtain an mcache.
-//
-// Returns nil if we're not bootstrapping or we don't have a P. The caller's
-// P must not change, so we must be in a non-preemptible state.
-func getMCache(mp *m) *mcache {
-	// Grab the mcache, since that's where stats live.
-	pp := mp.p.ptr()
-	var c *mcache
-	if pp == nil {
-		// We will be called without a P while bootstrapping,
-		// in which case we use mcache0, which is set in mallocinit.
-		// mcache0 is cleared when bootstrapping is complete,
-		// by procresize.
-		c = mcache0
-	} else {
-		c = pp.mcache
-	}
-	return c
-}
-
-// refill acquires a new span of span class spc for c. This span will
-// have at least one free object. The current span in c must be full.
-//
-// Must run in a non-preemptible context since otherwise the owner of
-// c could change.
-func (c *mcache) refill(spc spanClass) {
-	// Return the current cached span to the central lists.
-	s := c.alloc[spc]
-
-	if uintptr(s.allocCount) != s.nelems {
-		throw("refill of span with free space remaining")
-	}
-	if s != &emptymspan {
-		// Mark this span as no longer cached.
-		if s.sweepgen != mheap_.sweepgen+3 {
-			throw("bad sweepgen in refill")
-		}
-		mheap_.central[spc].mcentral.uncacheSpan(s)
-	}
-
-	// Get a new cached span from the central lists.
-	s = mheap_.central[spc].mcentral.cacheSpan()
-	if s == nil {
-		throw("out of memory")
-	}
-
-	if uintptr(s.allocCount) == s.nelems {
-		throw("span has no free space")
-	}
-
-	// Indicate that this span is cached and prevent asynchronous
-	// sweeping in the next sweep phase.
-	s.sweepgen = mheap_.sweepgen + 3
-
-	// Assume all objects from this span will be allocated in the
-	// mcache. If it gets uncached, we'll adjust this.
-	stats := memstats.heapStats.acquire()
-	atomic.Xadd64(&stats.smallAllocCount[spc.sizeclass()], int64(s.nelems)-int64(s.allocCount))
-
-	// Flush tinyAllocs.
-	if spc == tinySpanClass {
-		atomic.Xadd64(&stats.tinyAllocCount, int64(c.tinyAllocs))
-		c.tinyAllocs = 0
-	}
-	memstats.heapStats.release()
-
-	// Update heapLive with the same assumption.
-	// While we're here, flush scanAlloc, since we have to call
-	// revise anyway.
-	usedBytes := uintptr(s.allocCount) * s.elemsize
-	gcController.update(int64(s.npages*pageSize)-int64(usedBytes), int64(c.scanAlloc))
-	c.scanAlloc = 0
-
-	c.alloc[spc] = s
-}
-
-// allocLarge allocates a span for a large object.
-func (c *mcache) allocLarge(size uintptr, noscan bool) *mspan {
-	if size+_PageSize < size {
-		throw("out of memory")
-	}
-	npages := size >> _PageShift
-	if size&_PageMask != 0 {
-		npages++
-	}
-
-	// Deduct credit for this span allocation and sweep if
-	// necessary. mHeap_Alloc will also sweep npages, so this only
-	// pays the debt down to npage pages.
-	deductSweepCredit(npages*_PageSize, npages)
-
-	spc := makeSpanClass(0, noscan)
-	s := mheap_.alloc(npages, spc)
-	if s == nil {
-		throw("out of memory")
-	}
-	stats := memstats.heapStats.acquire()
-	atomic.Xadd64(&stats.largeAlloc, int64(npages*pageSize))
-	atomic.Xadd64(&stats.largeAllocCount, 1)
-	memstats.heapStats.release()
-
-	// Update heapLive.
-	gcController.update(int64(s.npages*pageSize), 0)
-
-	// Put the large span in the mcentral swept list so that it's
-	// visible to the background sweeper.
-	mheap_.central[spc].mcentral.fullSwept(mheap_.sweepgen).push(s)
-	s.limit = s.base() + size
-	heapBitsForAddr(s.base()).initSpan(s)
-	return s
-}
-
-func (c *mcache) releaseAll() {
-	// Take this opportunity to flush scanAlloc.
-	scanAlloc := int64(c.scanAlloc)
-	c.scanAlloc = 0
-
-	sg := mheap_.sweepgen
-	dHeapLive := int64(0)
-	for i := range c.alloc {
-		s := c.alloc[i]
-		if s != &emptymspan {
-			// Adjust nsmallalloc in case the span wasn't fully allocated.
-			n := int64(s.nelems) - int64(s.allocCount)
-			stats := memstats.heapStats.acquire()
-			atomic.Xadd64(&stats.smallAllocCount[spanClass(i).sizeclass()], -n)
-			memstats.heapStats.release()
-			if s.sweepgen != sg+1 {
-				// refill conservatively counted unallocated slots in gcController.heapLive.
-				// Undo this.
-				//
-				// If this span was cached before sweep, then
-				// gcController.heapLive was totally recomputed since
-				// caching this span, so we don't do this for
-				// stale spans.
-				dHeapLive -= n * int64(s.elemsize)
-			}
-			// Release the span to the mcentral.
-			mheap_.central[i].mcentral.uncacheSpan(s)
-			c.alloc[i] = &emptymspan
-		}
-	}
-	// Clear tinyalloc pool.
-	c.tiny = 0
-	c.tinyoffset = 0
-
-	// Flush tinyAllocs.
-	stats := memstats.heapStats.acquire()
-	atomic.Xadd64(&stats.tinyAllocCount, int64(c.tinyAllocs))
-	c.tinyAllocs = 0
-	memstats.heapStats.release()
-
-	// Updated heapScan and heapLive.
-	gcController.update(dHeapLive, scanAlloc)
-}
-
-// prepareForSweep flushes c if the system has entered a new sweep phase
-// since c was populated. This must happen between the sweep phase
-// starting and the first allocation from c.
-func (c *mcache) prepareForSweep() {
-	// Alternatively, instead of making sure we do this on every P
-	// between starting the world and allocating on that P, we
-	// could leave allocate-black on, allow allocation to continue
-	// as usual, use a ragged barrier at the beginning of sweep to
-	// ensure all cached spans are swept, and then disable
-	// allocate-black. However, with this approach it's difficult
-	// to avoid spilling mark bits into the *next* GC cycle.
-	sg := mheap_.sweepgen
-	if c.flushGen == sg {
-		return
-	} else if c.flushGen != sg-2 {
-		println("bad flushGen", c.flushGen, "in prepareForSweep; sweepgen", sg)
-		throw("bad flushGen")
-	}
-	c.releaseAll()
-	stackcache_clear(c)
-	atomic.Store(&c.flushGen, mheap_.sweepgen) // Synchronizes with gcStart
-}
diff --git a/contrib/go/_std_1.18/src/runtime/mem_darwin.go b/contrib/go/_std_1.18/src/runtime/mem_darwin.go
deleted file mode 100644
index 9f836c0818..0000000000
--- a/contrib/go/_std_1.18/src/runtime/mem_darwin.go
+++ /dev/null
@@ -1,72 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"unsafe"
-)
-
-// Don't split the stack as this function may be invoked without a valid G,
-// which prevents us from allocating more stack.
-//go:nosplit
-func sysAlloc(n uintptr, sysStat *sysMemStat) unsafe.Pointer {
-	v, err := mmap(nil, n, _PROT_READ|_PROT_WRITE, _MAP_ANON|_MAP_PRIVATE, -1, 0)
-	if err != 0 {
-		return nil
-	}
-	sysStat.add(int64(n))
-	return v
-}
-
-func sysUnused(v unsafe.Pointer, n uintptr) {
-	// MADV_FREE_REUSABLE is like MADV_FREE except it also propagates
-	// accounting information about the process to task_info.
-	madvise(v, n, _MADV_FREE_REUSABLE)
-}
-
-func sysUsed(v unsafe.Pointer, n uintptr) {
-	// MADV_FREE_REUSE is necessary to keep the kernel's accounting
-	// accurate. If called on any memory region that hasn't been
-	// MADV_FREE_REUSABLE'd, it's a no-op.
-	madvise(v, n, _MADV_FREE_REUSE)
-}
-
-func sysHugePage(v unsafe.Pointer, n uintptr) {
-}
-
-// Don't split the stack as this function may be invoked without a valid G,
-// which prevents us from allocating more stack.
-//go:nosplit
-func sysFree(v unsafe.Pointer, n uintptr, sysStat *sysMemStat) {
-	sysStat.add(-int64(n))
-	munmap(v, n)
-}
-
-func sysFault(v unsafe.Pointer, n uintptr) {
-	mmap(v, n, _PROT_NONE, _MAP_ANON|_MAP_PRIVATE|_MAP_FIXED, -1, 0)
-}
-
-func sysReserve(v unsafe.Pointer, n uintptr) unsafe.Pointer {
-	p, err := mmap(v, n, _PROT_NONE, _MAP_ANON|_MAP_PRIVATE, -1, 0)
-	if err != 0 {
-		return nil
-	}
-	return p
-}
-
-const _ENOMEM = 12
-
-func sysMap(v unsafe.Pointer, n uintptr, sysStat *sysMemStat) {
-	sysStat.add(int64(n))
-
-	p, err := mmap(v, n, _PROT_READ|_PROT_WRITE, _MAP_ANON|_MAP_FIXED|_MAP_PRIVATE, -1, 0)
-	if err == _ENOMEM {
-		throw("runtime: out of memory")
-	}
-	if p != v || err != 0 {
-		print("runtime: mmap(", v, ", ", n, ") returned ", p, ", ", err, "\n")
-		throw("runtime: cannot map pages in arena address space")
-	}
-}
diff --git a/contrib/go/_std_1.18/src/runtime/mem_linux.go b/contrib/go/_std_1.18/src/runtime/mem_linux.go
deleted file mode 100644
index f8333014c2..0000000000
--- a/contrib/go/_std_1.18/src/runtime/mem_linux.go
+++ /dev/null
@@ -1,195 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"runtime/internal/atomic"
-	"unsafe"
-)
-
-const (
-	_EACCES = 13
-	_EINVAL = 22
-)
-
-// Don't split the stack as this method may be invoked without a valid G, which
-// prevents us from allocating more stack.
-//go:nosplit
-func sysAlloc(n uintptr, sysStat *sysMemStat) unsafe.Pointer {
-	p, err := mmap(nil, n, _PROT_READ|_PROT_WRITE, _MAP_ANON|_MAP_PRIVATE, -1, 0)
-	if err != 0 {
-		if err == _EACCES {
-			print("runtime: mmap: access denied\n")
-			exit(2)
-		}
-		if err == _EAGAIN {
-			print("runtime: mmap: too much locked memory (check 'ulimit -l').\n")
-			exit(2)
-		}
-		return nil
-	}
-	sysStat.add(int64(n))
-	return p
-}
-
-var adviseUnused = uint32(_MADV_FREE)
-
-func sysUnused(v unsafe.Pointer, n uintptr) {
-	// By default, Linux's "transparent huge page" support will
-	// merge pages into a huge page if there's even a single
-	// present regular page, undoing the effects of madvise(adviseUnused)
-	// below. On amd64, that means khugepaged can turn a single
-	// 4KB page to 2MB, bloating the process's RSS by as much as
-	// 512X. (See issue #8832 and Linux kernel bug
-	// https://bugzilla.kernel.org/show_bug.cgi?id=93111)
-	//
-	// To work around this, we explicitly disable transparent huge
-	// pages when we release pages of the heap. However, we have
-	// to do this carefully because changing this flag tends to
-	// split the VMA (memory mapping) containing v in to three
-	// VMAs in order to track the different values of the
-	// MADV_NOHUGEPAGE flag in the different regions. There's a
-	// default limit of 65530 VMAs per address space (sysctl
-	// vm.max_map_count), so we must be careful not to create too
-	// many VMAs (see issue #12233).
-	//
-	// Since huge pages are huge, there's little use in adjusting
-	// the MADV_NOHUGEPAGE flag on a fine granularity, so we avoid
-	// exploding the number of VMAs by only adjusting the
-	// MADV_NOHUGEPAGE flag on a large granularity. This still
-	// gets most of the benefit of huge pages while keeping the
-	// number of VMAs under control. With hugePageSize = 2MB, even
-	// a pessimal heap can reach 128GB before running out of VMAs.
-	if physHugePageSize != 0 {
-		// If it's a large allocation, we want to leave huge
-		// pages enabled. Hence, we only adjust the huge page
-		// flag on the huge pages containing v and v+n-1, and
-		// only if those aren't aligned.
-		var head, tail uintptr
-		if uintptr(v)&(physHugePageSize-1) != 0 {
-			// Compute huge page containing v.
-			head = alignDown(uintptr(v), physHugePageSize)
-		}
-		if (uintptr(v)+n)&(physHugePageSize-1) != 0 {
-			// Compute huge page containing v+n-1.
-			tail = alignDown(uintptr(v)+n-1, physHugePageSize)
-		}
-
-		// Note that madvise will return EINVAL if the flag is
-		// already set, which is quite likely. We ignore
-		// errors.
-		if head != 0 && head+physHugePageSize == tail {
-			// head and tail are different but adjacent,
-			// so do this in one call.
-			madvise(unsafe.Pointer(head), 2*physHugePageSize, _MADV_NOHUGEPAGE)
-		} else {
-			// Advise the huge pages containing v and v+n-1.
-			if head != 0 {
-				madvise(unsafe.Pointer(head), physHugePageSize, _MADV_NOHUGEPAGE)
-			}
-			if tail != 0 && tail != head {
-				madvise(unsafe.Pointer(tail), physHugePageSize, _MADV_NOHUGEPAGE)
-			}
-		}
-	}
-
-	if uintptr(v)&(physPageSize-1) != 0 || n&(physPageSize-1) != 0 {
-		// madvise will round this to any physical page
-		// *covered* by this range, so an unaligned madvise
-		// will release more memory than intended.
-		throw("unaligned sysUnused")
-	}
-
-	var advise uint32
-	if debug.madvdontneed != 0 {
-		advise = _MADV_DONTNEED
-	} else {
-		advise = atomic.Load(&adviseUnused)
-	}
-	if errno := madvise(v, n, int32(advise)); advise == _MADV_FREE && errno != 0 {
-		// MADV_FREE was added in Linux 4.5. Fall back to MADV_DONTNEED if it is
-		// not supported.
-		atomic.Store(&adviseUnused, _MADV_DONTNEED)
-		madvise(v, n, _MADV_DONTNEED)
-	}
-
-	if debug.harddecommit > 0 {
-		p, err := mmap(v, n, _PROT_NONE, _MAP_ANON|_MAP_FIXED|_MAP_PRIVATE, -1, 0)
-		if p != v || err != 0 {
-			throw("runtime: cannot disable permissions in address space")
-		}
-	}
-}
-
-func sysUsed(v unsafe.Pointer, n uintptr) {
-	if debug.harddecommit > 0 {
-		p, err := mmap(v, n, _PROT_READ|_PROT_WRITE, _MAP_ANON|_MAP_FIXED|_MAP_PRIVATE, -1, 0)
-		if err == _ENOMEM {
-			throw("runtime: out of memory")
-		}
-		if p != v || err != 0 {
-			throw("runtime: cannot remap pages in address space")
-		}
-		return
-
-		// Don't do the sysHugePage optimization in hard decommit mode.
-		// We're breaking up pages everywhere, there's no point.
-	}
-	// Partially undo the NOHUGEPAGE marks from sysUnused
-	// for whole huge pages between v and v+n. This may
-	// leave huge pages off at the end points v and v+n
-	// even though allocations may cover these entire huge
-	// pages. We could detect this and undo NOHUGEPAGE on
-	// the end points as well, but it's probably not worth
-	// the cost because when neighboring allocations are
-	// freed sysUnused will just set NOHUGEPAGE again.
-	sysHugePage(v, n)
-}
-
-func sysHugePage(v unsafe.Pointer, n uintptr) {
-	if physHugePageSize != 0 {
-		// Round v up to a huge page boundary.
-		beg := alignUp(uintptr(v), physHugePageSize)
-		// Round v+n down to a huge page boundary.
-		end := alignDown(uintptr(v)+n, physHugePageSize)
-
-		if beg < end {
-			madvise(unsafe.Pointer(beg), end-beg, _MADV_HUGEPAGE)
-		}
-	}
-}
-
-// Don't split the stack as this function may be invoked without a valid G,
-// which prevents us from allocating more stack.
-//go:nosplit
-func sysFree(v unsafe.Pointer, n uintptr, sysStat *sysMemStat) {
-	sysStat.add(-int64(n))
-	munmap(v, n)
-}
-
-func sysFault(v unsafe.Pointer, n uintptr) {
-	mmap(v, n, _PROT_NONE, _MAP_ANON|_MAP_PRIVATE|_MAP_FIXED, -1, 0)
-}
-
-func sysReserve(v unsafe.Pointer, n uintptr) unsafe.Pointer {
-	p, err := mmap(v, n, _PROT_NONE, _MAP_ANON|_MAP_PRIVATE, -1, 0)
-	if err != 0 {
-		return nil
-	}
-	return p
-}
-
-func sysMap(v unsafe.Pointer, n uintptr, sysStat *sysMemStat) {
-	sysStat.add(int64(n))
-
-	p, err := mmap(v, n, _PROT_READ|_PROT_WRITE, _MAP_ANON|_MAP_FIXED|_MAP_PRIVATE, -1, 0)
-	if err == _ENOMEM {
-		throw("runtime: out of memory")
-	}
-	if p != v || err != 0 {
-		print("runtime: mmap(", v, ", ", n, ") returned ", p, ", ", err, "\n")
-		throw("runtime: cannot map pages in arena address space")
-	}
-}
diff --git a/contrib/go/_std_1.18/src/runtime/memclr_amd64.s b/contrib/go/_std_1.18/src/runtime/memclr_amd64.s
deleted file mode 100644
index 700bbd7b9b..0000000000
--- a/contrib/go/_std_1.18/src/runtime/memclr_amd64.s
+++ /dev/null
@@ -1,179 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build !plan9
-
-#include "go_asm.h"
-#include "textflag.h"
-
-// See memclrNoHeapPointers Go doc for important implementation constraints.
-
-// func memclrNoHeapPointers(ptr unsafe.Pointer, n uintptr)
-// ABIInternal for performance.
-TEXT runtime·memclrNoHeapPointers<ABIInternal>(SB), NOSPLIT, $0-16
-	// AX = ptr
-	// BX = n
-	MOVQ	AX, DI	// DI = ptr
-	XORQ	AX, AX
-
-	// MOVOU seems always faster than REP STOSQ.
-tail:
-	// BSR+branch table make almost all memmove/memclr benchmarks worse. Not worth doing.
-	TESTQ	BX, BX
-	JEQ	_0
-	CMPQ	BX, $2
-	JBE	_1or2
-	CMPQ	BX, $4
-	JBE	_3or4
-	CMPQ	BX, $8
-	JB	_5through7
-	JE	_8
-	CMPQ	BX, $16
-	JBE	_9through16
-	CMPQ	BX, $32
-	JBE	_17through32
-	CMPQ	BX, $64
-	JBE	_33through64
-	CMPQ	BX, $128
-	JBE	_65through128
-	CMPQ	BX, $256
-	JBE	_129through256
-	CMPB	internal∕cpu·X86+const_offsetX86HasAVX2(SB), $1
-	JE loop_preheader_avx2
-	// TODO: for really big clears, use MOVNTDQ, even without AVX2.
-
-loop:
-	MOVOU	X15, 0(DI)
-	MOVOU	X15, 16(DI)
-	MOVOU	X15, 32(DI)
-	MOVOU	X15, 48(DI)
-	MOVOU	X15, 64(DI)
-	MOVOU	X15, 80(DI)
-	MOVOU	X15, 96(DI)
-	MOVOU	X15, 112(DI)
-	MOVOU	X15, 128(DI)
-	MOVOU	X15, 144(DI)
-	MOVOU	X15, 160(DI)
-	MOVOU	X15, 176(DI)
-	MOVOU	X15, 192(DI)
-	MOVOU	X15, 208(DI)
-	MOVOU	X15, 224(DI)
-	MOVOU	X15, 240(DI)
-	SUBQ	$256, BX
-	ADDQ	$256, DI
-	CMPQ	BX, $256
-	JAE	loop
-	JMP	tail
-
-loop_preheader_avx2:
-	VPXOR Y0, Y0, Y0
-	// For smaller sizes MOVNTDQ may be faster or slower depending on hardware.
-	// For larger sizes it is always faster, even on dual Xeons with 30M cache.
-	// TODO take into account actual LLC size. E. g. glibc uses LLC size/2.
-	CMPQ    BX, $0x2000000
-	JAE     loop_preheader_avx2_huge
-loop_avx2:
-	VMOVDQU	Y0, 0(DI)
-	VMOVDQU	Y0, 32(DI)
-	VMOVDQU	Y0, 64(DI)
-	VMOVDQU	Y0, 96(DI)
-	SUBQ	$128, BX
-	ADDQ	$128, DI
-	CMPQ	BX, $128
-	JAE	loop_avx2
-	VMOVDQU  Y0, -32(DI)(BX*1)
-	VMOVDQU  Y0, -64(DI)(BX*1)
-	VMOVDQU  Y0, -96(DI)(BX*1)
-	VMOVDQU  Y0, -128(DI)(BX*1)
-	VZEROUPPER
-	RET
-loop_preheader_avx2_huge:
-	// Align to 32 byte boundary
-	VMOVDQU  Y0, 0(DI)
-	MOVQ	DI, SI
-	ADDQ	$32, DI
-	ANDQ	$~31, DI
-	SUBQ	DI, SI
-	ADDQ	SI, BX
-loop_avx2_huge:
-	VMOVNTDQ	Y0, 0(DI)
-	VMOVNTDQ	Y0, 32(DI)
-	VMOVNTDQ	Y0, 64(DI)
-	VMOVNTDQ	Y0, 96(DI)
-	SUBQ	$128, BX
-	ADDQ	$128, DI
-	CMPQ	BX, $128
-	JAE	loop_avx2_huge
-	// In the description of MOVNTDQ in [1]
-	// "... fencing operation implemented with the SFENCE or MFENCE instruction
-	// should be used in conjunction with MOVNTDQ instructions..."
-	// [1] 64-ia-32-architectures-software-developer-manual-325462.pdf
-	SFENCE
-	VMOVDQU  Y0, -32(DI)(BX*1)
-	VMOVDQU  Y0, -64(DI)(BX*1)
-	VMOVDQU  Y0, -96(DI)(BX*1)
-	VMOVDQU  Y0, -128(DI)(BX*1)
-	VZEROUPPER
-	RET
-
-_1or2:
-	MOVB	AX, (DI)
-	MOVB	AX, -1(DI)(BX*1)
-	RET
-_0:
-	RET
-_3or4:
-	MOVW	AX, (DI)
-	MOVW	AX, -2(DI)(BX*1)
-	RET
-_5through7:
-	MOVL	AX, (DI)
-	MOVL	AX, -4(DI)(BX*1)
-	RET
-_8:
-	// We need a separate case for 8 to make sure we clear pointers atomically.
-	MOVQ	AX, (DI)
-	RET
-_9through16:
-	MOVQ	AX, (DI)
-	MOVQ	AX, -8(DI)(BX*1)
-	RET
-_17through32:
-	MOVOU	X15, (DI)
-	MOVOU	X15, -16(DI)(BX*1)
-	RET
-_33through64:
-	MOVOU	X15, (DI)
-	MOVOU	X15, 16(DI)
-	MOVOU	X15, -32(DI)(BX*1)
-	MOVOU	X15, -16(DI)(BX*1)
-	RET
-_65through128:
-	MOVOU	X15, (DI)
-	MOVOU	X15, 16(DI)
-	MOVOU	X15, 32(DI)
-	MOVOU	X15, 48(DI)
-	MOVOU	X15, -64(DI)(BX*1)
-	MOVOU	X15, -48(DI)(BX*1)
-	MOVOU	X15, -32(DI)(BX*1)
-	MOVOU	X15, -16(DI)(BX*1)
-	RET
-_129through256:
-	MOVOU	X15, (DI)
-	MOVOU	X15, 16(DI)
-	MOVOU	X15, 32(DI)
-	MOVOU	X15, 48(DI)
-	MOVOU	X15, 64(DI)
-	MOVOU	X15, 80(DI)
-	MOVOU	X15, 96(DI)
-	MOVOU	X15, 112(DI)
-	MOVOU	X15, -128(DI)(BX*1)
-	MOVOU	X15, -112(DI)(BX*1)
-	MOVOU	X15, -96(DI)(BX*1)
-	MOVOU	X15, -80(DI)(BX*1)
-	MOVOU	X15, -64(DI)(BX*1)
-	MOVOU	X15, -48(DI)(BX*1)
-	MOVOU	X15, -32(DI)(BX*1)
-	MOVOU	X15, -16(DI)(BX*1)
-	RET
diff --git a/contrib/go/_std_1.18/src/runtime/memmove_amd64.s b/contrib/go/_std_1.18/src/runtime/memmove_amd64.s
deleted file mode 100644
index eeb5033fd9..0000000000
--- a/contrib/go/_std_1.18/src/runtime/memmove_amd64.s
+++ /dev/null
@@ -1,532 +0,0 @@
-// Derived from Inferno's libkern/memmove-386.s (adapted for amd64)
-// https://bitbucket.org/inferno-os/inferno-os/src/master/libkern/memmove-386.s
-//
-//         Copyright © 1994-1999 Lucent Technologies Inc. All rights reserved.
-//         Revisions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com).  All rights reserved.
-//         Portions Copyright 2009 The Go Authors. All rights reserved.
-//
-// Permission is hereby granted, free of charge, to any person obtaining a copy
-// of this software and associated documentation files (the "Software"), to deal
-// in the Software without restriction, including without limitation the rights
-// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-// copies of the Software, and to permit persons to whom the Software is
-// furnished to do so, subject to the following conditions:
-//
-// The above copyright notice and this permission notice shall be included in
-// all copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
-// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-// THE SOFTWARE.
-
-//go:build !plan9
-
-#include "go_asm.h"
-#include "textflag.h"
-
-// See memmove Go doc for important implementation constraints.
-
-// func memmove(to, from unsafe.Pointer, n uintptr)
-// ABIInternal for performance.
-TEXT runtime·memmove<ABIInternal>(SB), NOSPLIT, $0-24
-	// AX = to
-	// BX = from
-	// CX = n
-	MOVQ	AX, DI
-	MOVQ	BX, SI
-	MOVQ	CX, BX
-
-	// REP instructions have a high startup cost, so we handle small sizes
-	// with some straightline code. The REP MOVSQ instruction is really fast
-	// for large sizes. The cutover is approximately 2K.
-tail:
-	// move_129through256 or smaller work whether or not the source and the
-	// destination memory regions overlap because they load all data into
-	// registers before writing it back.  move_256through2048 on the other
-	// hand can be used only when the memory regions don't overlap or the copy
-	// direction is forward.
-	//
-	// BSR+branch table make almost all memmove/memclr benchmarks worse. Not worth doing.
-	TESTQ	BX, BX
-	JEQ	move_0
-	CMPQ	BX, $2
-	JBE	move_1or2
-	CMPQ	BX, $4
-	JB	move_3
-	JBE	move_4
-	CMPQ	BX, $8
-	JB	move_5through7
-	JE	move_8
-	CMPQ	BX, $16
-	JBE	move_9through16
-	CMPQ	BX, $32
-	JBE	move_17through32
-	CMPQ	BX, $64
-	JBE	move_33through64
-	CMPQ	BX, $128
-	JBE	move_65through128
-	CMPQ	BX, $256
-	JBE	move_129through256
-
-	TESTB	$1, runtime·useAVXmemmove(SB)
-	JNZ	avxUnaligned
-
-/*
- * check and set for backwards
- */
-	CMPQ	SI, DI
-	JLS	back
-
-/*
- * forward copy loop
- */
-forward:
-	CMPQ	BX, $2048
-	JLS	move_256through2048
-
-	// If REP MOVSB isn't fast, don't use it
-	CMPB	internal∕cpu·X86+const_offsetX86HasERMS(SB), $1 // enhanced REP MOVSB/STOSB
-	JNE	fwdBy8
-
-	// Check alignment
-	MOVL	SI, AX
-	ORL	DI, AX
-	TESTL	$7, AX
-	JEQ	fwdBy8
-
-	// Do 1 byte at a time
-	MOVQ	BX, CX
-	REP;	MOVSB
-	RET
-
-fwdBy8:
-	// Do 8 bytes at a time
-	MOVQ	BX, CX
-	SHRQ	$3, CX
-	ANDQ	$7, BX
-	REP;	MOVSQ
-	JMP	tail
-
-back:
-/*
- * check overlap
- */
-	MOVQ	SI, CX
-	ADDQ	BX, CX
-	CMPQ	CX, DI
-	JLS	forward
-/*
- * whole thing backwards has
- * adjusted addresses
- */
-	ADDQ	BX, DI
-	ADDQ	BX, SI
-	STD
-
-/*
- * copy
- */
-	MOVQ	BX, CX
-	SHRQ	$3, CX
-	ANDQ	$7, BX
-
-	SUBQ	$8, DI
-	SUBQ	$8, SI
-	REP;	MOVSQ
-
-	CLD
-	ADDQ	$8, DI
-	ADDQ	$8, SI
-	SUBQ	BX, DI
-	SUBQ	BX, SI
-	JMP	tail
-
-move_1or2:
-	MOVB	(SI), AX
-	MOVB	-1(SI)(BX*1), CX
-	MOVB	AX, (DI)
-	MOVB	CX, -1(DI)(BX*1)
-	RET
-move_0:
-	RET
-move_4:
-	MOVL	(SI), AX
-	MOVL	AX, (DI)
-	RET
-move_3:
-	MOVW	(SI), AX
-	MOVB	2(SI), CX
-	MOVW	AX, (DI)
-	MOVB	CX, 2(DI)
-	RET
-move_5through7:
-	MOVL	(SI), AX
-	MOVL	-4(SI)(BX*1), CX
-	MOVL	AX, (DI)
-	MOVL	CX, -4(DI)(BX*1)
-	RET
-move_8:
-	// We need a separate case for 8 to make sure we write pointers atomically.
-	MOVQ	(SI), AX
-	MOVQ	AX, (DI)
-	RET
-move_9through16:
-	MOVQ	(SI), AX
-	MOVQ	-8(SI)(BX*1), CX
-	MOVQ	AX, (DI)
-	MOVQ	CX, -8(DI)(BX*1)
-	RET
-move_17through32:
-	MOVOU	(SI), X0
-	MOVOU	-16(SI)(BX*1), X1
-	MOVOU	X0, (DI)
-	MOVOU	X1, -16(DI)(BX*1)
-	RET
-move_33through64:
-	MOVOU	(SI), X0
-	MOVOU	16(SI), X1
-	MOVOU	-32(SI)(BX*1), X2
-	MOVOU	-16(SI)(BX*1), X3
-	MOVOU	X0, (DI)
-	MOVOU	X1, 16(DI)
-	MOVOU	X2, -32(DI)(BX*1)
-	MOVOU	X3, -16(DI)(BX*1)
-	RET
-move_65through128:
-	MOVOU	(SI), X0
-	MOVOU	16(SI), X1
-	MOVOU	32(SI), X2
-	MOVOU	48(SI), X3
-	MOVOU	-64(SI)(BX*1), X4
-	MOVOU	-48(SI)(BX*1), X5
-	MOVOU	-32(SI)(BX*1), X6
-	MOVOU	-16(SI)(BX*1), X7
-	MOVOU	X0, (DI)
-	MOVOU	X1, 16(DI)
-	MOVOU	X2, 32(DI)
-	MOVOU	X3, 48(DI)
-	MOVOU	X4, -64(DI)(BX*1)
-	MOVOU	X5, -48(DI)(BX*1)
-	MOVOU	X6, -32(DI)(BX*1)
-	MOVOU	X7, -16(DI)(BX*1)
-	RET
-move_129through256:
-	MOVOU	(SI), X0
-	MOVOU	16(SI), X1
-	MOVOU	32(SI), X2
-	MOVOU	48(SI), X3
-	MOVOU	64(SI), X4
-	MOVOU	80(SI), X5
-	MOVOU	96(SI), X6
-	MOVOU	112(SI), X7
-	MOVOU	-128(SI)(BX*1), X8
-	MOVOU	-112(SI)(BX*1), X9
-	MOVOU	-96(SI)(BX*1), X10
-	MOVOU	-80(SI)(BX*1), X11
-	MOVOU	-64(SI)(BX*1), X12
-	MOVOU	-48(SI)(BX*1), X13
-	MOVOU	-32(SI)(BX*1), X14
-	MOVOU	-16(SI)(BX*1), X15
-	MOVOU	X0, (DI)
-	MOVOU	X1, 16(DI)
-	MOVOU	X2, 32(DI)
-	MOVOU	X3, 48(DI)
-	MOVOU	X4, 64(DI)
-	MOVOU	X5, 80(DI)
-	MOVOU	X6, 96(DI)
-	MOVOU	X7, 112(DI)
-	MOVOU	X8, -128(DI)(BX*1)
-	MOVOU	X9, -112(DI)(BX*1)
-	MOVOU	X10, -96(DI)(BX*1)
-	MOVOU	X11, -80(DI)(BX*1)
-	MOVOU	X12, -64(DI)(BX*1)
-	MOVOU	X13, -48(DI)(BX*1)
-	MOVOU	X14, -32(DI)(BX*1)
-	MOVOU	X15, -16(DI)(BX*1)
-	// X15 must be zero on return
-	PXOR	X15, X15
-	RET
-move_256through2048:
-	SUBQ	$256, BX
-	MOVOU	(SI), X0
-	MOVOU	16(SI), X1
-	MOVOU	32(SI), X2
-	MOVOU	48(SI), X3
-	MOVOU	64(SI), X4
-	MOVOU	80(SI), X5
-	MOVOU	96(SI), X6
-	MOVOU	112(SI), X7
-	MOVOU	128(SI), X8
-	MOVOU	144(SI), X9
-	MOVOU	160(SI), X10
-	MOVOU	176(SI), X11
-	MOVOU	192(SI), X12
-	MOVOU	208(SI), X13
-	MOVOU	224(SI), X14
-	MOVOU	240(SI), X15
-	MOVOU	X0, (DI)
-	MOVOU	X1, 16(DI)
-	MOVOU	X2, 32(DI)
-	MOVOU	X3, 48(DI)
-	MOVOU	X4, 64(DI)
-	MOVOU	X5, 80(DI)
-	MOVOU	X6, 96(DI)
-	MOVOU	X7, 112(DI)
-	MOVOU	X8, 128(DI)
-	MOVOU	X9, 144(DI)
-	MOVOU	X10, 160(DI)
-	MOVOU	X11, 176(DI)
-	MOVOU	X12, 192(DI)
-	MOVOU	X13, 208(DI)
-	MOVOU	X14, 224(DI)
-	MOVOU	X15, 240(DI)
-	CMPQ	BX, $256
-	LEAQ	256(SI), SI
-	LEAQ	256(DI), DI
-	JGE	move_256through2048
-	// X15 must be zero on return
-	PXOR	X15, X15
-	JMP	tail
-
-avxUnaligned:
-	// There are two implementations of move algorithm.
-	// The first one for non-overlapped memory regions. It uses forward copying.
-	// The second one for overlapped regions. It uses backward copying
-	MOVQ	DI, CX
-	SUBQ	SI, CX
-	// Now CX contains distance between SRC and DEST
-	CMPQ	CX, BX
-	// If the distance lesser than region length it means that regions are overlapped
-	JC	copy_backward
-
-	// Non-temporal copy would be better for big sizes.
-	CMPQ	BX, $0x100000
-	JAE	gobble_big_data_fwd
-
-	// Memory layout on the source side
-	// SI                                       CX
-	// |<---------BX before correction--------->|
-	// |       |<--BX corrected-->|             |
-	// |       |                  |<--- AX  --->|
-	// |<-R11->|                  |<-128 bytes->|
-	// +----------------------------------------+
-	// | Head  | Body             | Tail        |
-	// +-------+------------------+-------------+
-	// ^       ^                  ^
-	// |       |                  |
-	// Save head into Y4          Save tail into X5..X12
-	//         |
-	//         SI+R11, where R11 = ((DI & -32) + 32) - DI
-	// Algorithm:
-	// 1. Unaligned save of the tail's 128 bytes
-	// 2. Unaligned save of the head's 32  bytes
-	// 3. Destination-aligned copying of body (128 bytes per iteration)
-	// 4. Put head on the new place
-	// 5. Put the tail on the new place
-	// It can be important to satisfy processor's pipeline requirements for
-	// small sizes as the cost of unaligned memory region copying is
-	// comparable with the cost of main loop. So code is slightly messed there.
-	// There is more clean implementation of that algorithm for bigger sizes
-	// where the cost of unaligned part copying is negligible.
-	// You can see it after gobble_big_data_fwd label.
-	LEAQ	(SI)(BX*1), CX
-	MOVQ	DI, R10
-	// CX points to the end of buffer so we need go back slightly. We will use negative offsets there.
-	MOVOU	-0x80(CX), X5
-	MOVOU	-0x70(CX), X6
-	MOVQ	$0x80, AX
-	// Align destination address
-	ANDQ	$-32, DI
-	ADDQ	$32, DI
-	// Continue tail saving.
-	MOVOU	-0x60(CX), X7
-	MOVOU	-0x50(CX), X8
-	// Make R11 delta between aligned and unaligned destination addresses.
-	MOVQ	DI, R11
-	SUBQ	R10, R11
-	// Continue tail saving.
-	MOVOU	-0x40(CX), X9
-	MOVOU	-0x30(CX), X10
-	// Let's make bytes-to-copy value adjusted as we've prepared unaligned part for copying.
-	SUBQ	R11, BX
-	// Continue tail saving.
-	MOVOU	-0x20(CX), X11
-	MOVOU	-0x10(CX), X12
-	// The tail will be put on its place after main body copying.
-	// It's time for the unaligned heading part.
-	VMOVDQU	(SI), Y4
-	// Adjust source address to point past head.
-	ADDQ	R11, SI
-	SUBQ	AX, BX
-	// Aligned memory copying there
-gobble_128_loop:
-	VMOVDQU	(SI), Y0
-	VMOVDQU	0x20(SI), Y1
-	VMOVDQU	0x40(SI), Y2
-	VMOVDQU	0x60(SI), Y3
-	ADDQ	AX, SI
-	VMOVDQA	Y0, (DI)
-	VMOVDQA	Y1, 0x20(DI)
-	VMOVDQA	Y2, 0x40(DI)
-	VMOVDQA	Y3, 0x60(DI)
-	ADDQ	AX, DI
-	SUBQ	AX, BX
-	JA	gobble_128_loop
-	// Now we can store unaligned parts.
-	ADDQ	AX, BX
-	ADDQ	DI, BX
-	VMOVDQU	Y4, (R10)
-	VZEROUPPER
-	MOVOU	X5, -0x80(BX)
-	MOVOU	X6, -0x70(BX)
-	MOVOU	X7, -0x60(BX)
-	MOVOU	X8, -0x50(BX)
-	MOVOU	X9, -0x40(BX)
-	MOVOU	X10, -0x30(BX)
-	MOVOU	X11, -0x20(BX)
-	MOVOU	X12, -0x10(BX)
-	RET
-
-gobble_big_data_fwd:
-	// There is forward copying for big regions.
-	// It uses non-temporal mov instructions.
-	// Details of this algorithm are commented previously for small sizes.
-	LEAQ	(SI)(BX*1), CX
-	MOVOU	-0x80(SI)(BX*1), X5
-	MOVOU	-0x70(CX), X6
-	MOVOU	-0x60(CX), X7
-	MOVOU	-0x50(CX), X8
-	MOVOU	-0x40(CX), X9
-	MOVOU	-0x30(CX), X10
-	MOVOU	-0x20(CX), X11
-	MOVOU	-0x10(CX), X12
-	VMOVDQU	(SI), Y4
-	MOVQ	DI, R8
-	ANDQ	$-32, DI
-	ADDQ	$32, DI
-	MOVQ	DI, R10
-	SUBQ	R8, R10
-	SUBQ	R10, BX
-	ADDQ	R10, SI
-	LEAQ	(DI)(BX*1), CX
-	SUBQ	$0x80, BX
-gobble_mem_fwd_loop:
-	PREFETCHNTA 0x1C0(SI)
-	PREFETCHNTA 0x280(SI)
-	// Prefetch values were chosen empirically.
-	// Approach for prefetch usage as in 7.6.6 of [1]
-	// [1] 64-ia-32-architectures-optimization-manual.pdf
-	// https://www.intel.ru/content/dam/www/public/us/en/documents/manuals/64-ia-32-architectures-optimization-manual.pdf
-	VMOVDQU	(SI), Y0
-	VMOVDQU	0x20(SI), Y1
-	VMOVDQU	0x40(SI), Y2
-	VMOVDQU	0x60(SI), Y3
-	ADDQ	$0x80, SI
-	VMOVNTDQ Y0, (DI)
-	VMOVNTDQ Y1, 0x20(DI)
-	VMOVNTDQ Y2, 0x40(DI)
-	VMOVNTDQ Y3, 0x60(DI)
-	ADDQ	$0x80, DI
-	SUBQ	$0x80, BX
-	JA		gobble_mem_fwd_loop
-	// NT instructions don't follow the normal cache-coherency rules.
-	// We need SFENCE there to make copied data available timely.
-	SFENCE
-	VMOVDQU	Y4, (R8)
-	VZEROUPPER
-	MOVOU	X5, -0x80(CX)
-	MOVOU	X6, -0x70(CX)
-	MOVOU	X7, -0x60(CX)
-	MOVOU	X8, -0x50(CX)
-	MOVOU	X9, -0x40(CX)
-	MOVOU	X10, -0x30(CX)
-	MOVOU	X11, -0x20(CX)
-	MOVOU	X12, -0x10(CX)
-	RET
-
-copy_backward:
-	MOVQ	DI, AX
-	// Backward copying is about the same as the forward one.
-	// Firstly we load unaligned tail in the beginning of region.
-	MOVOU	(SI), X5
-	MOVOU	0x10(SI), X6
-	ADDQ	BX, DI
-	MOVOU	0x20(SI), X7
-	MOVOU	0x30(SI), X8
-	LEAQ	-0x20(DI), R10
-	MOVQ	DI, R11
-	MOVOU	0x40(SI), X9
-	MOVOU	0x50(SI), X10
-	ANDQ	$0x1F, R11
-	MOVOU	0x60(SI), X11
-	MOVOU	0x70(SI), X12
-	XORQ	R11, DI
-	// Let's point SI to the end of region
-	ADDQ	BX, SI
-	// and load unaligned head into X4.
-	VMOVDQU	-0x20(SI), Y4
-	SUBQ	R11, SI
-	SUBQ	R11, BX
-	// If there is enough data for non-temporal moves go to special loop
-	CMPQ	BX, $0x100000
-	JA		gobble_big_data_bwd
-	SUBQ	$0x80, BX
-gobble_mem_bwd_loop:
-	VMOVDQU	-0x20(SI), Y0
-	VMOVDQU	-0x40(SI), Y1
-	VMOVDQU	-0x60(SI), Y2
-	VMOVDQU	-0x80(SI), Y3
-	SUBQ	$0x80, SI
-	VMOVDQA	Y0, -0x20(DI)
-	VMOVDQA	Y1, -0x40(DI)
-	VMOVDQA	Y2, -0x60(DI)
-	VMOVDQA	Y3, -0x80(DI)
-	SUBQ	$0x80, DI
-	SUBQ	$0x80, BX
-	JA		gobble_mem_bwd_loop
-	// Let's store unaligned data
-	VMOVDQU	Y4, (R10)
-	VZEROUPPER
-	MOVOU	X5, (AX)
-	MOVOU	X6, 0x10(AX)
-	MOVOU	X7, 0x20(AX)
-	MOVOU	X8, 0x30(AX)
-	MOVOU	X9, 0x40(AX)
-	MOVOU	X10, 0x50(AX)
-	MOVOU	X11, 0x60(AX)
-	MOVOU	X12, 0x70(AX)
-	RET
-
-gobble_big_data_bwd:
-	SUBQ	$0x80, BX
-gobble_big_mem_bwd_loop:
-	PREFETCHNTA -0x1C0(SI)
-	PREFETCHNTA -0x280(SI)
-	VMOVDQU	-0x20(SI), Y0
-	VMOVDQU	-0x40(SI), Y1
-	VMOVDQU	-0x60(SI), Y2
-	VMOVDQU	-0x80(SI), Y3
-	SUBQ	$0x80, SI
-	VMOVNTDQ	Y0, -0x20(DI)
-	VMOVNTDQ	Y1, -0x40(DI)
-	VMOVNTDQ	Y2, -0x60(DI)
-	VMOVNTDQ	Y3, -0x80(DI)
-	SUBQ	$0x80, DI
-	SUBQ	$0x80, BX
-	JA	gobble_big_mem_bwd_loop
-	SFENCE
-	VMOVDQU	Y4, (R10)
-	VZEROUPPER
-	MOVOU	X5, (AX)
-	MOVOU	X6, 0x10(AX)
-	MOVOU	X7, 0x20(AX)
-	MOVOU	X8, 0x30(AX)
-	MOVOU	X9, 0x40(AX)
-	MOVOU	X10, 0x50(AX)
-	MOVOU	X11, 0x60(AX)
-	MOVOU	X12, 0x70(AX)
-	RET
diff --git a/contrib/go/_std_1.18/src/runtime/metrics.go b/contrib/go/_std_1.18/src/runtime/metrics.go
deleted file mode 100644
index 922dd2f814..0000000000
--- a/contrib/go/_std_1.18/src/runtime/metrics.go
+++ /dev/null
@@ -1,594 +0,0 @@
-// Copyright 2020 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-// Metrics implementation exported to runtime/metrics.
-
-import (
-	"runtime/internal/atomic"
-	"unsafe"
-)
-
-var (
-	// metrics is a map of runtime/metrics keys to data used by the runtime
-	// to sample each metric's value. metricsInit indicates it has been
-	// initialized.
-	//
-	// These fields are protected by metricsSema which should be
-	// locked/unlocked with metricsLock() / metricsUnlock().
-	metricsSema uint32 = 1
-	metricsInit bool
-	metrics     map[string]metricData
-
-	sizeClassBuckets []float64
-	timeHistBuckets  []float64
-)
-
-type metricData struct {
-	// deps is the set of runtime statistics that this metric
-	// depends on. Before compute is called, the statAggregate
-	// which will be passed must ensure() these dependencies.
-	deps statDepSet
-
-	// compute is a function that populates a metricValue
-	// given a populated statAggregate structure.
-	compute func(in *statAggregate, out *metricValue)
-}
-
-func metricsLock() {
-	// Acquire the metricsSema but with handoff. Operations are typically
-	// expensive enough that queueing up goroutines and handing off between
-	// them will be noticeably better-behaved.
-	semacquire1(&metricsSema, true, 0, 0)
-	if raceenabled {
-		raceacquire(unsafe.Pointer(&metricsSema))
-	}
-}
-
-func metricsUnlock() {
-	if raceenabled {
-		racerelease(unsafe.Pointer(&metricsSema))
-	}
-	semrelease(&metricsSema)
-}
-
-// initMetrics initializes the metrics map if it hasn't been yet.
-//
-// metricsSema must be held.
-func initMetrics() {
-	if metricsInit {
-		return
-	}
-
-	sizeClassBuckets = make([]float64, _NumSizeClasses, _NumSizeClasses+1)
-	// Skip size class 0 which is a stand-in for large objects, but large
-	// objects are tracked separately (and they actually get placed in
-	// the last bucket, not the first).
-	sizeClassBuckets[0] = 1 // The smallest allocation is 1 byte in size.
-	for i := 1; i < _NumSizeClasses; i++ {
-		// Size classes have an inclusive upper-bound
-		// and exclusive lower bound (e.g. 48-byte size class is
-		// (32, 48]) whereas we want and inclusive lower-bound
-		// and exclusive upper-bound (e.g. 48-byte size class is
-		// [33, 49). We can achieve this by shifting all bucket
-		// boundaries up by 1.
-		//
-		// Also, a float64 can precisely represent integers with
-		// value up to 2^53 and size classes are relatively small
-		// (nowhere near 2^48 even) so this will give us exact
-		// boundaries.
-		sizeClassBuckets[i] = float64(class_to_size[i] + 1)
-	}
-	sizeClassBuckets = append(sizeClassBuckets, float64Inf())
-
-	timeHistBuckets = timeHistogramMetricsBuckets()
-	metrics = map[string]metricData{
-		"/gc/cycles/automatic:gc-cycles": {
-			deps: makeStatDepSet(sysStatsDep),
-			compute: func(in *statAggregate, out *metricValue) {
-				out.kind = metricKindUint64
-				out.scalar = in.sysStats.gcCyclesDone - in.sysStats.gcCyclesForced
-			},
-		},
-		"/gc/cycles/forced:gc-cycles": {
-			deps: makeStatDepSet(sysStatsDep),
-			compute: func(in *statAggregate, out *metricValue) {
-				out.kind = metricKindUint64
-				out.scalar = in.sysStats.gcCyclesForced
-			},
-		},
-		"/gc/cycles/total:gc-cycles": {
-			deps: makeStatDepSet(sysStatsDep),
-			compute: func(in *statAggregate, out *metricValue) {
-				out.kind = metricKindUint64
-				out.scalar = in.sysStats.gcCyclesDone
-			},
-		},
-		"/gc/heap/allocs-by-size:bytes": {
-			deps: makeStatDepSet(heapStatsDep),
-			compute: func(in *statAggregate, out *metricValue) {
-				hist := out.float64HistOrInit(sizeClassBuckets)
-				hist.counts[len(hist.counts)-1] = uint64(in.heapStats.largeAllocCount)
-				// Cut off the first index which is ostensibly for size class 0,
-				// but large objects are tracked separately so it's actually unused.
-				for i, count := range in.heapStats.smallAllocCount[1:] {
-					hist.counts[i] = uint64(count)
-				}
-			},
-		},
-		"/gc/heap/allocs:bytes": {
-			deps: makeStatDepSet(heapStatsDep),
-			compute: func(in *statAggregate, out *metricValue) {
-				out.kind = metricKindUint64
-				out.scalar = in.heapStats.totalAllocated
-			},
-		},
-		"/gc/heap/allocs:objects": {
-			deps: makeStatDepSet(heapStatsDep),
-			compute: func(in *statAggregate, out *metricValue) {
-				out.kind = metricKindUint64
-				out.scalar = in.heapStats.totalAllocs
-			},
-		},
-		"/gc/heap/frees-by-size:bytes": {
-			deps: makeStatDepSet(heapStatsDep),
-			compute: func(in *statAggregate, out *metricValue) {
-				hist := out.float64HistOrInit(sizeClassBuckets)
-				hist.counts[len(hist.counts)-1] = uint64(in.heapStats.largeFreeCount)
-				// Cut off the first index which is ostensibly for size class 0,
-				// but large objects are tracked separately so it's actually unused.
-				for i, count := range in.heapStats.smallFreeCount[1:] {
-					hist.counts[i] = uint64(count)
-				}
-			},
-		},
-		"/gc/heap/frees:bytes": {
-			deps: makeStatDepSet(heapStatsDep),
-			compute: func(in *statAggregate, out *metricValue) {
-				out.kind = metricKindUint64
-				out.scalar = in.heapStats.totalFreed
-			},
-		},
-		"/gc/heap/frees:objects": {
-			deps: makeStatDepSet(heapStatsDep),
-			compute: func(in *statAggregate, out *metricValue) {
-				out.kind = metricKindUint64
-				out.scalar = in.heapStats.totalFrees
-			},
-		},
-		"/gc/heap/goal:bytes": {
-			deps: makeStatDepSet(sysStatsDep),
-			compute: func(in *statAggregate, out *metricValue) {
-				out.kind = metricKindUint64
-				out.scalar = in.sysStats.heapGoal
-			},
-		},
-		"/gc/heap/objects:objects": {
-			deps: makeStatDepSet(heapStatsDep),
-			compute: func(in *statAggregate, out *metricValue) {
-				out.kind = metricKindUint64
-				out.scalar = in.heapStats.numObjects
-			},
-		},
-		"/gc/heap/tiny/allocs:objects": {
-			deps: makeStatDepSet(heapStatsDep),
-			compute: func(in *statAggregate, out *metricValue) {
-				out.kind = metricKindUint64
-				out.scalar = uint64(in.heapStats.tinyAllocCount)
-			},
-		},
-		"/gc/pauses:seconds": {
-			compute: func(_ *statAggregate, out *metricValue) {
-				hist := out.float64HistOrInit(timeHistBuckets)
-				// The bottom-most bucket, containing negative values, is tracked
-				// as a separately as underflow, so fill that in manually and then
-				// iterate over the rest.
-				hist.counts[0] = atomic.Load64(&memstats.gcPauseDist.underflow)
-				for i := range memstats.gcPauseDist.counts {
-					hist.counts[i+1] = atomic.Load64(&memstats.gcPauseDist.counts[i])
-				}
-			},
-		},
-		"/memory/classes/heap/free:bytes": {
-			deps: makeStatDepSet(heapStatsDep),
-			compute: func(in *statAggregate, out *metricValue) {
-				out.kind = metricKindUint64
-				out.scalar = uint64(in.heapStats.committed - in.heapStats.inHeap -
-					in.heapStats.inStacks - in.heapStats.inWorkBufs -
-					in.heapStats.inPtrScalarBits)
-			},
-		},
-		"/memory/classes/heap/objects:bytes": {
-			deps: makeStatDepSet(heapStatsDep),
-			compute: func(in *statAggregate, out *metricValue) {
-				out.kind = metricKindUint64
-				out.scalar = in.heapStats.inObjects
-			},
-		},
-		"/memory/classes/heap/released:bytes": {
-			deps: makeStatDepSet(heapStatsDep),
-			compute: func(in *statAggregate, out *metricValue) {
-				out.kind = metricKindUint64
-				out.scalar = uint64(in.heapStats.released)
-			},
-		},
-		"/memory/classes/heap/stacks:bytes": {
-			deps: makeStatDepSet(heapStatsDep),
-			compute: func(in *statAggregate, out *metricValue) {
-				out.kind = metricKindUint64
-				out.scalar = uint64(in.heapStats.inStacks)
-			},
-		},
-		"/memory/classes/heap/unused:bytes": {
-			deps: makeStatDepSet(heapStatsDep),
-			compute: func(in *statAggregate, out *metricValue) {
-				out.kind = metricKindUint64
-				out.scalar = uint64(in.heapStats.inHeap) - in.heapStats.inObjects
-			},
-		},
-		"/memory/classes/metadata/mcache/free:bytes": {
-			deps: makeStatDepSet(sysStatsDep),
-			compute: func(in *statAggregate, out *metricValue) {
-				out.kind = metricKindUint64
-				out.scalar = in.sysStats.mCacheSys - in.sysStats.mCacheInUse
-			},
-		},
-		"/memory/classes/metadata/mcache/inuse:bytes": {
-			deps: makeStatDepSet(sysStatsDep),
-			compute: func(in *statAggregate, out *metricValue) {
-				out.kind = metricKindUint64
-				out.scalar = in.sysStats.mCacheInUse
-			},
-		},
-		"/memory/classes/metadata/mspan/free:bytes": {
-			deps: makeStatDepSet(sysStatsDep),
-			compute: func(in *statAggregate, out *metricValue) {
-				out.kind = metricKindUint64
-				out.scalar = in.sysStats.mSpanSys - in.sysStats.mSpanInUse
-			},
-		},
-		"/memory/classes/metadata/mspan/inuse:bytes": {
-			deps: makeStatDepSet(sysStatsDep),
-			compute: func(in *statAggregate, out *metricValue) {
-				out.kind = metricKindUint64
-				out.scalar = in.sysStats.mSpanInUse
-			},
-		},
-		"/memory/classes/metadata/other:bytes": {
-			deps: makeStatDepSet(heapStatsDep, sysStatsDep),
-			compute: func(in *statAggregate, out *metricValue) {
-				out.kind = metricKindUint64
-				out.scalar = uint64(in.heapStats.inWorkBufs+in.heapStats.inPtrScalarBits) + in.sysStats.gcMiscSys
-			},
-		},
-		"/memory/classes/os-stacks:bytes": {
-			deps: makeStatDepSet(sysStatsDep),
-			compute: func(in *statAggregate, out *metricValue) {
-				out.kind = metricKindUint64
-				out.scalar = in.sysStats.stacksSys
-			},
-		},
-		"/memory/classes/other:bytes": {
-			deps: makeStatDepSet(sysStatsDep),
-			compute: func(in *statAggregate, out *metricValue) {
-				out.kind = metricKindUint64
-				out.scalar = in.sysStats.otherSys
-			},
-		},
-		"/memory/classes/profiling/buckets:bytes": {
-			deps: makeStatDepSet(sysStatsDep),
-			compute: func(in *statAggregate, out *metricValue) {
-				out.kind = metricKindUint64
-				out.scalar = in.sysStats.buckHashSys
-			},
-		},
-		"/memory/classes/total:bytes": {
-			deps: makeStatDepSet(heapStatsDep, sysStatsDep),
-			compute: func(in *statAggregate, out *metricValue) {
-				out.kind = metricKindUint64
-				out.scalar = uint64(in.heapStats.committed+in.heapStats.released) +
-					in.sysStats.stacksSys + in.sysStats.mSpanSys +
-					in.sysStats.mCacheSys + in.sysStats.buckHashSys +
-					in.sysStats.gcMiscSys + in.sysStats.otherSys
-			},
-		},
-		"/sched/goroutines:goroutines": {
-			compute: func(_ *statAggregate, out *metricValue) {
-				out.kind = metricKindUint64
-				out.scalar = uint64(gcount())
-			},
-		},
-		"/sched/latencies:seconds": {
-			compute: func(_ *statAggregate, out *metricValue) {
-				hist := out.float64HistOrInit(timeHistBuckets)
-				hist.counts[0] = atomic.Load64(&sched.timeToRun.underflow)
-				for i := range sched.timeToRun.counts {
-					hist.counts[i+1] = atomic.Load64(&sched.timeToRun.counts[i])
-				}
-			},
-		},
-	}
-	metricsInit = true
-}
-
-// statDep is a dependency on a group of statistics
-// that a metric might have.
-type statDep uint
-
-const (
-	heapStatsDep statDep = iota // corresponds to heapStatsAggregate
-	sysStatsDep                 // corresponds to sysStatsAggregate
-	numStatsDeps
-)
-
-// statDepSet represents a set of statDeps.
-//
-// Under the hood, it's a bitmap.
-type statDepSet [1]uint64
-
-// makeStatDepSet creates a new statDepSet from a list of statDeps.
-func makeStatDepSet(deps ...statDep) statDepSet {
-	var s statDepSet
-	for _, d := range deps {
-		s[d/64] |= 1 << (d % 64)
-	}
-	return s
-}
-
-// differennce returns set difference of s from b as a new set.
-func (s statDepSet) difference(b statDepSet) statDepSet {
-	var c statDepSet
-	for i := range s {
-		c[i] = s[i] &^ b[i]
-	}
-	return c
-}
-
-// union returns the union of the two sets as a new set.
-func (s statDepSet) union(b statDepSet) statDepSet {
-	var c statDepSet
-	for i := range s {
-		c[i] = s[i] | b[i]
-	}
-	return c
-}
-
-// empty returns true if there are no dependencies in the set.
-func (s *statDepSet) empty() bool {
-	for _, c := range s {
-		if c != 0 {
-			return false
-		}
-	}
-	return true
-}
-
-// has returns true if the set contains a given statDep.
-func (s *statDepSet) has(d statDep) bool {
-	return s[d/64]&(1<<(d%64)) != 0
-}
-
-// heapStatsAggregate represents memory stats obtained from the
-// runtime. This set of stats is grouped together because they
-// depend on each other in some way to make sense of the runtime's
-// current heap memory use. They're also sharded across Ps, so it
-// makes sense to grab them all at once.
-type heapStatsAggregate struct {
-	heapStatsDelta
-
-	// Derived from values in heapStatsDelta.
-
-	// inObjects is the bytes of memory occupied by objects,
-	inObjects uint64
-
-	// numObjects is the number of live objects in the heap.
-	numObjects uint64
-
-	// totalAllocated is the total bytes of heap objects allocated
-	// over the lifetime of the program.
-	totalAllocated uint64
-
-	// totalFreed is the total bytes of heap objects freed
-	// over the lifetime of the program.
-	totalFreed uint64
-
-	// totalAllocs is the number of heap objects allocated over
-	// the lifetime of the program.
-	totalAllocs uint64
-
-	// totalFrees is the number of heap objects freed over
-	// the lifetime of the program.
-	totalFrees uint64
-}
-
-// compute populates the heapStatsAggregate with values from the runtime.
-func (a *heapStatsAggregate) compute() {
-	memstats.heapStats.read(&a.heapStatsDelta)
-
-	// Calculate derived stats.
-	a.totalAllocs = a.largeAllocCount
-	a.totalFrees = a.largeFreeCount
-	a.totalAllocated = a.largeAlloc
-	a.totalFreed = a.largeFree
-	for i := range a.smallAllocCount {
-		na := a.smallAllocCount[i]
-		nf := a.smallFreeCount[i]
-		a.totalAllocs += na
-		a.totalFrees += nf
-		a.totalAllocated += na * uint64(class_to_size[i])
-		a.totalFreed += nf * uint64(class_to_size[i])
-	}
-	a.inObjects = a.totalAllocated - a.totalFreed
-	a.numObjects = a.totalAllocs - a.totalFrees
-}
-
-// sysStatsAggregate represents system memory stats obtained
-// from the runtime. This set of stats is grouped together because
-// they're all relatively cheap to acquire and generally independent
-// of one another and other runtime memory stats. The fact that they
-// may be acquired at different times, especially with respect to
-// heapStatsAggregate, means there could be some skew, but because of
-// these stats are independent, there's no real consistency issue here.
-type sysStatsAggregate struct {
-	stacksSys      uint64
-	mSpanSys       uint64
-	mSpanInUse     uint64
-	mCacheSys      uint64
-	mCacheInUse    uint64
-	buckHashSys    uint64
-	gcMiscSys      uint64
-	otherSys       uint64
-	heapGoal       uint64
-	gcCyclesDone   uint64
-	gcCyclesForced uint64
-}
-
-// compute populates the sysStatsAggregate with values from the runtime.
-func (a *sysStatsAggregate) compute() {
-	a.stacksSys = memstats.stacks_sys.load()
-	a.buckHashSys = memstats.buckhash_sys.load()
-	a.gcMiscSys = memstats.gcMiscSys.load()
-	a.otherSys = memstats.other_sys.load()
-	a.heapGoal = atomic.Load64(&gcController.heapGoal)
-	a.gcCyclesDone = uint64(memstats.numgc)
-	a.gcCyclesForced = uint64(memstats.numforcedgc)
-
-	systemstack(func() {
-		lock(&mheap_.lock)
-		a.mSpanSys = memstats.mspan_sys.load()
-		a.mSpanInUse = uint64(mheap_.spanalloc.inuse)
-		a.mCacheSys = memstats.mcache_sys.load()
-		a.mCacheInUse = uint64(mheap_.cachealloc.inuse)
-		unlock(&mheap_.lock)
-	})
-}
-
-// statAggregate is the main driver of the metrics implementation.
-//
-// It contains multiple aggregates of runtime statistics, as well
-// as a set of these aggregates that it has populated. The aggergates
-// are populated lazily by its ensure method.
-type statAggregate struct {
-	ensured   statDepSet
-	heapStats heapStatsAggregate
-	sysStats  sysStatsAggregate
-}
-
-// ensure populates statistics aggregates determined by deps if they
-// haven't yet been populated.
-func (a *statAggregate) ensure(deps *statDepSet) {
-	missing := deps.difference(a.ensured)
-	if missing.empty() {
-		return
-	}
-	for i := statDep(0); i < numStatsDeps; i++ {
-		if !missing.has(i) {
-			continue
-		}
-		switch i {
-		case heapStatsDep:
-			a.heapStats.compute()
-		case sysStatsDep:
-			a.sysStats.compute()
-		}
-	}
-	a.ensured = a.ensured.union(missing)
-}
-
-// metricValidKind is a runtime copy of runtime/metrics.ValueKind and
-// must be kept structurally identical to that type.
-type metricKind int
-
-const (
-	// These values must be kept identical to their corresponding Kind* values
-	// in the runtime/metrics package.
-	metricKindBad metricKind = iota
-	metricKindUint64
-	metricKindFloat64
-	metricKindFloat64Histogram
-)
-
-// metricSample is a runtime copy of runtime/metrics.Sample and
-// must be kept structurally identical to that type.
-type metricSample struct {
-	name  string
-	value metricValue
-}
-
-// metricValue is a runtime copy of runtime/metrics.Sample and
-// must be kept structurally identical to that type.
-type metricValue struct {
-	kind    metricKind
-	scalar  uint64         // contains scalar values for scalar Kinds.
-	pointer unsafe.Pointer // contains non-scalar values.
-}
-
-// float64HistOrInit tries to pull out an existing float64Histogram
-// from the value, but if none exists, then it allocates one with
-// the given buckets.
-func (v *metricValue) float64HistOrInit(buckets []float64) *metricFloat64Histogram {
-	var hist *metricFloat64Histogram
-	if v.kind == metricKindFloat64Histogram && v.pointer != nil {
-		hist = (*metricFloat64Histogram)(v.pointer)
-	} else {
-		v.kind = metricKindFloat64Histogram
-		hist = new(metricFloat64Histogram)
-		v.pointer = unsafe.Pointer(hist)
-	}
-	hist.buckets = buckets
-	if len(hist.counts) != len(hist.buckets)-1 {
-		hist.counts = make([]uint64, len(buckets)-1)
-	}
-	return hist
-}
-
-// metricFloat64Histogram is a runtime copy of runtime/metrics.Float64Histogram
-// and must be kept structurally identical to that type.
-type metricFloat64Histogram struct {
-	counts  []uint64
-	buckets []float64
-}
-
-// agg is used by readMetrics, and is protected by metricsSema.
-//
-// Managed as a global variable because its pointer will be
-// an argument to a dynamically-defined function, and we'd
-// like to avoid it escaping to the heap.
-var agg statAggregate
-
-// readMetrics is the implementation of runtime/metrics.Read.
-//
-//go:linkname readMetrics runtime/metrics.runtime_readMetrics
-func readMetrics(samplesp unsafe.Pointer, len int, cap int) {
-	// Construct a slice from the args.
-	sl := slice{samplesp, len, cap}
-	samples := *(*[]metricSample)(unsafe.Pointer(&sl))
-
-	metricsLock()
-
-	// Ensure the map is initialized.
-	initMetrics()
-
-	// Clear agg defensively.
-	agg = statAggregate{}
-
-	// Sample.
-	for i := range samples {
-		sample := &samples[i]
-		data, ok := metrics[sample.name]
-		if !ok {
-			sample.value.kind = metricKindBad
-			continue
-		}
-		// Ensure we have all the stats we need.
-		// agg is populated lazily.
-		agg.ensure(&data.deps)
-
-		// Compute the value based on the stats we have.
-		data.compute(&agg, &sample.value)
-	}
-
-	metricsUnlock()
-}
diff --git a/contrib/go/_std_1.18/src/runtime/mfinal.go b/contrib/go/_std_1.18/src/runtime/mfinal.go
deleted file mode 100644
index 10623e4d67..0000000000
--- a/contrib/go/_std_1.18/src/runtime/mfinal.go
+++ /dev/null
@@ -1,474 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Garbage collector: finalizers and block profiling.
-
-package runtime
-
-import (
-	"internal/abi"
-	"internal/goarch"
-	"runtime/internal/atomic"
-	"unsafe"
-)
-
-// finblock is an array of finalizers to be executed. finblocks are
-// arranged in a linked list for the finalizer queue.
-//
-// finblock is allocated from non-GC'd memory, so any heap pointers
-// must be specially handled. GC currently assumes that the finalizer
-// queue does not grow during marking (but it can shrink).
-//
-//go:notinheap
-type finblock struct {
-	alllink *finblock
-	next    *finblock
-	cnt     uint32
-	_       int32
-	fin     [(_FinBlockSize - 2*goarch.PtrSize - 2*4) / unsafe.Sizeof(finalizer{})]finalizer
-}
-
-var finlock mutex  // protects the following variables
-var fing *g        // goroutine that runs finalizers
-var finq *finblock // list of finalizers that are to be executed
-var finc *finblock // cache of free blocks
-var finptrmask [_FinBlockSize / goarch.PtrSize / 8]byte
-var fingwait bool
-var fingwake bool
-var allfin *finblock // list of all blocks
-
-// NOTE: Layout known to queuefinalizer.
-type finalizer struct {
-	fn   *funcval       // function to call (may be a heap pointer)
-	arg  unsafe.Pointer // ptr to object (may be a heap pointer)
-	nret uintptr        // bytes of return values from fn
-	fint *_type         // type of first argument of fn
-	ot   *ptrtype       // type of ptr to object (may be a heap pointer)
-}
-
-var finalizer1 = [...]byte{
-	// Each Finalizer is 5 words, ptr ptr INT ptr ptr (INT = uintptr here)
-	// Each byte describes 8 words.
-	// Need 8 Finalizers described by 5 bytes before pattern repeats:
-	//	ptr ptr INT ptr ptr
-	//	ptr ptr INT ptr ptr
-	//	ptr ptr INT ptr ptr
-	//	ptr ptr INT ptr ptr
-	//	ptr ptr INT ptr ptr
-	//	ptr ptr INT ptr ptr
-	//	ptr ptr INT ptr ptr
-	//	ptr ptr INT ptr ptr
-	// aka
-	//
-	//	ptr ptr INT ptr ptr ptr ptr INT
-	//	ptr ptr ptr ptr INT ptr ptr ptr
-	//	ptr INT ptr ptr ptr ptr INT ptr
-	//	ptr ptr ptr INT ptr ptr ptr ptr
-	//	INT ptr ptr ptr ptr INT ptr ptr
-	//
-	// Assumptions about Finalizer layout checked below.
-	1<<0 | 1<<1 | 0<<2 | 1<<3 | 1<<4 | 1<<5 | 1<<6 | 0<<7,
-	1<<0 | 1<<1 | 1<<2 | 1<<3 | 0<<4 | 1<<5 | 1<<6 | 1<<7,
-	1<<0 | 0<<1 | 1<<2 | 1<<3 | 1<<4 | 1<<5 | 0<<6 | 1<<7,
-	1<<0 | 1<<1 | 1<<2 | 0<<3 | 1<<4 | 1<<5 | 1<<6 | 1<<7,
-	0<<0 | 1<<1 | 1<<2 | 1<<3 | 1<<4 | 0<<5 | 1<<6 | 1<<7,
-}
-
-func queuefinalizer(p unsafe.Pointer, fn *funcval, nret uintptr, fint *_type, ot *ptrtype) {
-	if gcphase != _GCoff {
-		// Currently we assume that the finalizer queue won't
-		// grow during marking so we don't have to rescan it
-		// during mark termination. If we ever need to lift
-		// this assumption, we can do it by adding the
-		// necessary barriers to queuefinalizer (which it may
-		// have automatically).
-		throw("queuefinalizer during GC")
-	}
-
-	lock(&finlock)
-	if finq == nil || finq.cnt == uint32(len(finq.fin)) {
-		if finc == nil {
-			finc = (*finblock)(persistentalloc(_FinBlockSize, 0, &memstats.gcMiscSys))
-			finc.alllink = allfin
-			allfin = finc
-			if finptrmask[0] == 0 {
-				// Build pointer mask for Finalizer array in block.
-				// Check assumptions made in finalizer1 array above.
-				if (unsafe.Sizeof(finalizer{}) != 5*goarch.PtrSize ||
-					unsafe.Offsetof(finalizer{}.fn) != 0 ||
-					unsafe.Offsetof(finalizer{}.arg) != goarch.PtrSize ||
-					unsafe.Offsetof(finalizer{}.nret) != 2*goarch.PtrSize ||
-					unsafe.Offsetof(finalizer{}.fint) != 3*goarch.PtrSize ||
-					unsafe.Offsetof(finalizer{}.ot) != 4*goarch.PtrSize) {
-					throw("finalizer out of sync")
-				}
-				for i := range finptrmask {
-					finptrmask[i] = finalizer1[i%len(finalizer1)]
-				}
-			}
-		}
-		block := finc
-		finc = block.next
-		block.next = finq
-		finq = block
-	}
-	f := &finq.fin[finq.cnt]
-	atomic.Xadd(&finq.cnt, +1) // Sync with markroots
-	f.fn = fn
-	f.nret = nret
-	f.fint = fint
-	f.ot = ot
-	f.arg = p
-	fingwake = true
-	unlock(&finlock)
-}
-
-//go:nowritebarrier
-func iterate_finq(callback func(*funcval, unsafe.Pointer, uintptr, *_type, *ptrtype)) {
-	for fb := allfin; fb != nil; fb = fb.alllink {
-		for i := uint32(0); i < fb.cnt; i++ {
-			f := &fb.fin[i]
-			callback(f.fn, f.arg, f.nret, f.fint, f.ot)
-		}
-	}
-}
-
-func wakefing() *g {
-	var res *g
-	lock(&finlock)
-	if fingwait && fingwake {
-		fingwait = false
-		fingwake = false
-		res = fing
-	}
-	unlock(&finlock)
-	return res
-}
-
-var (
-	fingCreate  uint32
-	fingRunning bool
-)
-
-func createfing() {
-	// start the finalizer goroutine exactly once
-	if fingCreate == 0 && atomic.Cas(&fingCreate, 0, 1) {
-		go runfinq()
-	}
-}
-
-// This is the goroutine that runs all of the finalizers
-func runfinq() {
-	var (
-		frame    unsafe.Pointer
-		framecap uintptr
-		argRegs  int
-	)
-
-	for {
-		lock(&finlock)
-		fb := finq
-		finq = nil
-		if fb == nil {
-			gp := getg()
-			fing = gp
-			fingwait = true
-			goparkunlock(&finlock, waitReasonFinalizerWait, traceEvGoBlock, 1)
-			continue
-		}
-		argRegs = intArgRegs
-		unlock(&finlock)
-		if raceenabled {
-			racefingo()
-		}
-		for fb != nil {
-			for i := fb.cnt; i > 0; i-- {
-				f := &fb.fin[i-1]
-
-				var regs abi.RegArgs
-				// The args may be passed in registers or on stack. Even for
-				// the register case, we still need the spill slots.
-				// TODO: revisit if we remove spill slots.
-				//
-				// Unfortunately because we can have an arbitrary
-				// amount of returns and it would be complex to try and
-				// figure out how many of those can get passed in registers,
-				// just conservatively assume none of them do.
-				framesz := unsafe.Sizeof((any)(nil)) + f.nret
-				if framecap < framesz {
-					// The frame does not contain pointers interesting for GC,
-					// all not yet finalized objects are stored in finq.
-					// If we do not mark it as FlagNoScan,
-					// the last finalized object is not collected.
-					frame = mallocgc(framesz, nil, true)
-					framecap = framesz
-				}
-
-				if f.fint == nil {
-					throw("missing type in runfinq")
-				}
-				r := frame
-				if argRegs > 0 {
-					r = unsafe.Pointer(&regs.Ints)
-				} else {
-					// frame is effectively uninitialized
-					// memory. That means we have to clear
-					// it before writing to it to avoid
-					// confusing the write barrier.
-					*(*[2]uintptr)(frame) = [2]uintptr{}
-				}
-				switch f.fint.kind & kindMask {
-				case kindPtr:
-					// direct use of pointer
-					*(*unsafe.Pointer)(r) = f.arg
-				case kindInterface:
-					ityp := (*interfacetype)(unsafe.Pointer(f.fint))
-					// set up with empty interface
-					(*eface)(r)._type = &f.ot.typ
-					(*eface)(r).data = f.arg
-					if len(ityp.mhdr) != 0 {
-						// convert to interface with methods
-						// this conversion is guaranteed to succeed - we checked in SetFinalizer
-						(*iface)(r).tab = assertE2I(ityp, (*eface)(r)._type)
-					}
-				default:
-					throw("bad kind in runfinq")
-				}
-				fingRunning = true
-				reflectcall(nil, unsafe.Pointer(f.fn), frame, uint32(framesz), uint32(framesz), uint32(framesz), &regs)
-				fingRunning = false
-
-				// Drop finalizer queue heap references
-				// before hiding them from markroot.
-				// This also ensures these will be
-				// clear if we reuse the finalizer.
-				f.fn = nil
-				f.arg = nil
-				f.ot = nil
-				atomic.Store(&fb.cnt, i-1)
-			}
-			next := fb.next
-			lock(&finlock)
-			fb.next = finc
-			finc = fb
-			unlock(&finlock)
-			fb = next
-		}
-	}
-}
-
-// SetFinalizer sets the finalizer associated with obj to the provided
-// finalizer function. When the garbage collector finds an unreachable block
-// with an associated finalizer, it clears the association and runs
-// finalizer(obj) in a separate goroutine. This makes obj reachable again,
-// but now without an associated finalizer. Assuming that SetFinalizer
-// is not called again, the next time the garbage collector sees
-// that obj is unreachable, it will free obj.
-//
-// SetFinalizer(obj, nil) clears any finalizer associated with obj.
-//
-// The argument obj must be a pointer to an object allocated by calling
-// new, by taking the address of a composite literal, or by taking the
-// address of a local variable.
-// The argument finalizer must be a function that takes a single argument
-// to which obj's type can be assigned, and can have arbitrary ignored return
-// values. If either of these is not true, SetFinalizer may abort the
-// program.
-//
-// Finalizers are run in dependency order: if A points at B, both have
-// finalizers, and they are otherwise unreachable, only the finalizer
-// for A runs; once A is freed, the finalizer for B can run.
-// If a cyclic structure includes a block with a finalizer, that
-// cycle is not guaranteed to be garbage collected and the finalizer
-// is not guaranteed to run, because there is no ordering that
-// respects the dependencies.
-//
-// The finalizer is scheduled to run at some arbitrary time after the
-// program can no longer reach the object to which obj points.
-// There is no guarantee that finalizers will run before a program exits,
-// so typically they are useful only for releasing non-memory resources
-// associated with an object during a long-running program.
-// For example, an os.File object could use a finalizer to close the
-// associated operating system file descriptor when a program discards
-// an os.File without calling Close, but it would be a mistake
-// to depend on a finalizer to flush an in-memory I/O buffer such as a
-// bufio.Writer, because the buffer would not be flushed at program exit.
-//
-// It is not guaranteed that a finalizer will run if the size of *obj is
-// zero bytes.
-//
-// It is not guaranteed that a finalizer will run for objects allocated
-// in initializers for package-level variables. Such objects may be
-// linker-allocated, not heap-allocated.
-//
-// A finalizer may run as soon as an object becomes unreachable.
-// In order to use finalizers correctly, the program must ensure that
-// the object is reachable until it is no longer required.
-// Objects stored in global variables, or that can be found by tracing
-// pointers from a global variable, are reachable. For other objects,
-// pass the object to a call of the KeepAlive function to mark the
-// last point in the function where the object must be reachable.
-//
-// For example, if p points to a struct, such as os.File, that contains
-// a file descriptor d, and p has a finalizer that closes that file
-// descriptor, and if the last use of p in a function is a call to
-// syscall.Write(p.d, buf, size), then p may be unreachable as soon as
-// the program enters syscall.Write. The finalizer may run at that moment,
-// closing p.d, causing syscall.Write to fail because it is writing to
-// a closed file descriptor (or, worse, to an entirely different
-// file descriptor opened by a different goroutine). To avoid this problem,
-// call runtime.KeepAlive(p) after the call to syscall.Write.
-//
-// A single goroutine runs all finalizers for a program, sequentially.
-// If a finalizer must run for a long time, it should do so by starting
-// a new goroutine.
-func SetFinalizer(obj any, finalizer any) {
-	if debug.sbrk != 0 {
-		// debug.sbrk never frees memory, so no finalizers run
-		// (and we don't have the data structures to record them).
-		return
-	}
-	e := efaceOf(&obj)
-	etyp := e._type
-	if etyp == nil {
-		throw("runtime.SetFinalizer: first argument is nil")
-	}
-	if etyp.kind&kindMask != kindPtr {
-		throw("runtime.SetFinalizer: first argument is " + etyp.string() + ", not pointer")
-	}
-	ot := (*ptrtype)(unsafe.Pointer(etyp))
-	if ot.elem == nil {
-		throw("nil elem type!")
-	}
-
-	// find the containing object
-	base, _, _ := findObject(uintptr(e.data), 0, 0)
-
-	if base == 0 {
-		// 0-length objects are okay.
-		if e.data == unsafe.Pointer(&zerobase) {
-			return
-		}
-
-		// Global initializers might be linker-allocated.
-		//	var Foo = &Object{}
-		//	func main() {
-		//		runtime.SetFinalizer(Foo, nil)
-		//	}
-		// The relevant segments are: noptrdata, data, bss, noptrbss.
-		// We cannot assume they are in any order or even contiguous,
-		// due to external linking.
-		for datap := &firstmoduledata; datap != nil; datap = datap.next {
-			if datap.noptrdata <= uintptr(e.data) && uintptr(e.data) < datap.enoptrdata ||
-				datap.data <= uintptr(e.data) && uintptr(e.data) < datap.edata ||
-				datap.bss <= uintptr(e.data) && uintptr(e.data) < datap.ebss ||
-				datap.noptrbss <= uintptr(e.data) && uintptr(e.data) < datap.enoptrbss {
-				return
-			}
-		}
-		throw("runtime.SetFinalizer: pointer not in allocated block")
-	}
-
-	if uintptr(e.data) != base {
-		// As an implementation detail we allow to set finalizers for an inner byte
-		// of an object if it could come from tiny alloc (see mallocgc for details).
-		if ot.elem == nil || ot.elem.ptrdata != 0 || ot.elem.size >= maxTinySize {
-			throw("runtime.SetFinalizer: pointer not at beginning of allocated block")
-		}
-	}
-
-	f := efaceOf(&finalizer)
-	ftyp := f._type
-	if ftyp == nil {
-		// switch to system stack and remove finalizer
-		systemstack(func() {
-			removefinalizer(e.data)
-		})
-		return
-	}
-
-	if ftyp.kind&kindMask != kindFunc {
-		throw("runtime.SetFinalizer: second argument is " + ftyp.string() + ", not a function")
-	}
-	ft := (*functype)(unsafe.Pointer(ftyp))
-	if ft.dotdotdot() {
-		throw("runtime.SetFinalizer: cannot pass " + etyp.string() + " to finalizer " + ftyp.string() + " because dotdotdot")
-	}
-	if ft.inCount != 1 {
-		throw("runtime.SetFinalizer: cannot pass " + etyp.string() + " to finalizer " + ftyp.string())
-	}
-	fint := ft.in()[0]
-	switch {
-	case fint == etyp:
-		// ok - same type
-		goto okarg
-	case fint.kind&kindMask == kindPtr:
-		if (fint.uncommon() == nil || etyp.uncommon() == nil) && (*ptrtype)(unsafe.Pointer(fint)).elem == ot.elem {
-			// ok - not same type, but both pointers,
-			// one or the other is unnamed, and same element type, so assignable.
-			goto okarg
-		}
-	case fint.kind&kindMask == kindInterface:
-		ityp := (*interfacetype)(unsafe.Pointer(fint))
-		if len(ityp.mhdr) == 0 {
-			// ok - satisfies empty interface
-			goto okarg
-		}
-		if iface := assertE2I2(ityp, *efaceOf(&obj)); iface.tab != nil {
-			goto okarg
-		}
-	}
-	throw("runtime.SetFinalizer: cannot pass " + etyp.string() + " to finalizer " + ftyp.string())
-okarg:
-	// compute size needed for return parameters
-	nret := uintptr(0)
-	for _, t := range ft.out() {
-		nret = alignUp(nret, uintptr(t.align)) + uintptr(t.size)
-	}
-	nret = alignUp(nret, goarch.PtrSize)
-
-	// make sure we have a finalizer goroutine
-	createfing()
-
-	systemstack(func() {
-		if !addfinalizer(e.data, (*funcval)(f.data), nret, fint, ot) {
-			throw("runtime.SetFinalizer: finalizer already set")
-		}
-	})
-}
-
-// Mark KeepAlive as noinline so that it is easily detectable as an intrinsic.
-//go:noinline
-
-// KeepAlive marks its argument as currently reachable.
-// This ensures that the object is not freed, and its finalizer is not run,
-// before the point in the program where KeepAlive is called.
-//
-// A very simplified example showing where KeepAlive is required:
-// 	type File struct { d int }
-// 	d, err := syscall.Open("/file/path", syscall.O_RDONLY, 0)
-// 	// ... do something if err != nil ...
-// 	p := &File{d}
-// 	runtime.SetFinalizer(p, func(p *File) { syscall.Close(p.d) })
-// 	var buf [10]byte
-// 	n, err := syscall.Read(p.d, buf[:])
-// 	// Ensure p is not finalized until Read returns.
-// 	runtime.KeepAlive(p)
-// 	// No more uses of p after this point.
-//
-// Without the KeepAlive call, the finalizer could run at the start of
-// syscall.Read, closing the file descriptor before syscall.Read makes
-// the actual system call.
-//
-// Note: KeepAlive should only be used to prevent finalizers from
-// running prematurely. In particular, when used with unsafe.Pointer,
-// the rules for valid uses of unsafe.Pointer still apply.
-func KeepAlive(x any) {
-	// Introduce a use of x that the compiler can't eliminate.
-	// This makes sure x is alive on entry. We need x to be alive
-	// on entry for "defer runtime.KeepAlive(x)"; see issue 21402.
-	if cgoAlwaysFalse {
-		println(x)
-	}
-}
diff --git a/contrib/go/_std_1.18/src/runtime/mgc.go b/contrib/go/_std_1.18/src/runtime/mgc.go
deleted file mode 100644
index 44b96154e7..0000000000
--- a/contrib/go/_std_1.18/src/runtime/mgc.go
+++ /dev/null
@@ -1,1714 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Garbage collector (GC).
-//
-// The GC runs concurrently with mutator threads, is type accurate (aka precise), allows multiple
-// GC thread to run in parallel. It is a concurrent mark and sweep that uses a write barrier. It is
-// non-generational and non-compacting. Allocation is done using size segregated per P allocation
-// areas to minimize fragmentation while eliminating locks in the common case.
-//
-// The algorithm decomposes into several steps.
-// This is a high level description of the algorithm being used. For an overview of GC a good
-// place to start is Richard Jones' gchandbook.org.
-//
-// The algorithm's intellectual heritage includes Dijkstra's on-the-fly algorithm, see
-// Edsger W. Dijkstra, Leslie Lamport, A. J. Martin, C. S. Scholten, and E. F. M. Steffens. 1978.
-// On-the-fly garbage collection: an exercise in cooperation. Commun. ACM 21, 11 (November 1978),
-// 966-975.
-// For journal quality proofs that these steps are complete, correct, and terminate see
-// Hudson, R., and Moss, J.E.B. Copying Garbage Collection without stopping the world.
-// Concurrency and Computation: Practice and Experience 15(3-5), 2003.
-//
-// 1. GC performs sweep termination.
-//
-//    a. Stop the world. This causes all Ps to reach a GC safe-point.
-//
-//    b. Sweep any unswept spans. There will only be unswept spans if
-//    this GC cycle was forced before the expected time.
-//
-// 2. GC performs the mark phase.
-//
-//    a. Prepare for the mark phase by setting gcphase to _GCmark
-//    (from _GCoff), enabling the write barrier, enabling mutator
-//    assists, and enqueueing root mark jobs. No objects may be
-//    scanned until all Ps have enabled the write barrier, which is
-//    accomplished using STW.
-//
-//    b. Start the world. From this point, GC work is done by mark
-//    workers started by the scheduler and by assists performed as
-//    part of allocation. The write barrier shades both the
-//    overwritten pointer and the new pointer value for any pointer
-//    writes (see mbarrier.go for details). Newly allocated objects
-//    are immediately marked black.
-//
-//    c. GC performs root marking jobs. This includes scanning all
-//    stacks, shading all globals, and shading any heap pointers in
-//    off-heap runtime data structures. Scanning a stack stops a
-//    goroutine, shades any pointers found on its stack, and then
-//    resumes the goroutine.
-//
-//    d. GC drains the work queue of grey objects, scanning each grey
-//    object to black and shading all pointers found in the object
-//    (which in turn may add those pointers to the work queue).
-//
-//    e. Because GC work is spread across local caches, GC uses a
-//    distributed termination algorithm to detect when there are no
-//    more root marking jobs or grey objects (see gcMarkDone). At this
-//    point, GC transitions to mark termination.
-//
-// 3. GC performs mark termination.
-//
-//    a. Stop the world.
-//
-//    b. Set gcphase to _GCmarktermination, and disable workers and
-//    assists.
-//
-//    c. Perform housekeeping like flushing mcaches.
-//
-// 4. GC performs the sweep phase.
-//
-//    a. Prepare for the sweep phase by setting gcphase to _GCoff,
-//    setting up sweep state and disabling the write barrier.
-//
-//    b. Start the world. From this point on, newly allocated objects
-//    are white, and allocating sweeps spans before use if necessary.
-//
-//    c. GC does concurrent sweeping in the background and in response
-//    to allocation. See description below.
-//
-// 5. When sufficient allocation has taken place, replay the sequence
-// starting with 1 above. See discussion of GC rate below.
-
-// Concurrent sweep.
-//
-// The sweep phase proceeds concurrently with normal program execution.
-// The heap is swept span-by-span both lazily (when a goroutine needs another span)
-// and concurrently in a background goroutine (this helps programs that are not CPU bound).
-// At the end of STW mark termination all spans are marked as "needs sweeping".
-//
-// The background sweeper goroutine simply sweeps spans one-by-one.
-//
-// To avoid requesting more OS memory while there are unswept spans, when a
-// goroutine needs another span, it first attempts to reclaim that much memory
-// by sweeping. When a goroutine needs to allocate a new small-object span, it
-// sweeps small-object spans for the same object size until it frees at least
-// one object. When a goroutine needs to allocate large-object span from heap,
-// it sweeps spans until it frees at least that many pages into heap. There is
-// one case where this may not suffice: if a goroutine sweeps and frees two
-// nonadjacent one-page spans to the heap, it will allocate a new two-page
-// span, but there can still be other one-page unswept spans which could be
-// combined into a two-page span.
-//
-// It's critical to ensure that no operations proceed on unswept spans (that would corrupt
-// mark bits in GC bitmap). During GC all mcaches are flushed into the central cache,
-// so they are empty. When a goroutine grabs a new span into mcache, it sweeps it.
-// When a goroutine explicitly frees an object or sets a finalizer, it ensures that
-// the span is swept (either by sweeping it, or by waiting for the concurrent sweep to finish).
-// The finalizer goroutine is kicked off only when all spans are swept.
-// When the next GC starts, it sweeps all not-yet-swept spans (if any).
-
-// GC rate.
-// Next GC is after we've allocated an extra amount of memory proportional to
-// the amount already in use. The proportion is controlled by GOGC environment variable
-// (100 by default). If GOGC=100 and we're using 4M, we'll GC again when we get to 8M
-// (this mark is tracked in gcController.heapGoal variable). This keeps the GC cost in
-// linear proportion to the allocation cost. Adjusting GOGC just changes the linear constant
-// (and also the amount of extra memory used).
-
-// Oblets
-//
-// In order to prevent long pauses while scanning large objects and to
-// improve parallelism, the garbage collector breaks up scan jobs for
-// objects larger than maxObletBytes into "oblets" of at most
-// maxObletBytes. When scanning encounters the beginning of a large
-// object, it scans only the first oblet and enqueues the remaining
-// oblets as new scan jobs.
-
-package runtime
-
-import (
-	"internal/cpu"
-	"runtime/internal/atomic"
-	"unsafe"
-)
-
-const (
-	_DebugGC         = 0
-	_ConcurrentSweep = true
-	_FinBlockSize    = 4 * 1024
-
-	// debugScanConservative enables debug logging for stack
-	// frames that are scanned conservatively.
-	debugScanConservative = false
-
-	// sweepMinHeapDistance is a lower bound on the heap distance
-	// (in bytes) reserved for concurrent sweeping between GC
-	// cycles.
-	sweepMinHeapDistance = 1024 * 1024
-)
-
-func gcinit() {
-	if unsafe.Sizeof(workbuf{}) != _WorkbufSize {
-		throw("size of Workbuf is suboptimal")
-	}
-	// No sweep on the first cycle.
-	sweep.active.state.Store(sweepDrainedMask)
-
-	// Initialize GC pacer state.
-	// Use the environment variable GOGC for the initial gcPercent value.
-	gcController.init(readGOGC())
-
-	work.startSema = 1
-	work.markDoneSema = 1
-	lockInit(&work.sweepWaiters.lock, lockRankSweepWaiters)
-	lockInit(&work.assistQueue.lock, lockRankAssistQueue)
-	lockInit(&work.wbufSpans.lock, lockRankWbufSpans)
-}
-
-// gcenable is called after the bulk of the runtime initialization,
-// just before we're about to start letting user code run.
-// It kicks off the background sweeper goroutine, the background
-// scavenger goroutine, and enables GC.
-func gcenable() {
-	// Kick off sweeping and scavenging.
-	c := make(chan int, 2)
-	go bgsweep(c)
-	go bgscavenge(c)
-	<-c
-	<-c
-	memstats.enablegc = true // now that runtime is initialized, GC is okay
-}
-
-// Garbage collector phase.
-// Indicates to write barrier and synchronization task to perform.
-var gcphase uint32
-
-// The compiler knows about this variable.
-// If you change it, you must change builtin/runtime.go, too.
-// If you change the first four bytes, you must also change the write
-// barrier insertion code.
-var writeBarrier struct {
-	enabled bool    // compiler emits a check of this before calling write barrier
-	pad     [3]byte // compiler uses 32-bit load for "enabled" field
-	needed  bool    // whether we need a write barrier for current GC phase
-	cgo     bool    // whether we need a write barrier for a cgo check
-	alignme uint64  // guarantee alignment so that compiler can use a 32 or 64-bit load
-}
-
-// gcBlackenEnabled is 1 if mutator assists and background mark
-// workers are allowed to blacken objects. This must only be set when
-// gcphase == _GCmark.
-var gcBlackenEnabled uint32
-
-const (
-	_GCoff             = iota // GC not running; sweeping in background, write barrier disabled
-	_GCmark                   // GC marking roots and workbufs: allocate black, write barrier ENABLED
-	_GCmarktermination        // GC mark termination: allocate black, P's help GC, write barrier ENABLED
-)
-
-//go:nosplit
-func setGCPhase(x uint32) {
-	atomic.Store(&gcphase, x)
-	writeBarrier.needed = gcphase == _GCmark || gcphase == _GCmarktermination
-	writeBarrier.enabled = writeBarrier.needed || writeBarrier.cgo
-}
-
-// gcMarkWorkerMode represents the mode that a concurrent mark worker
-// should operate in.
-//
-// Concurrent marking happens through four different mechanisms. One
-// is mutator assists, which happen in response to allocations and are
-// not scheduled. The other three are variations in the per-P mark
-// workers and are distinguished by gcMarkWorkerMode.
-type gcMarkWorkerMode int
-
-const (
-	// gcMarkWorkerNotWorker indicates that the next scheduled G is not
-	// starting work and the mode should be ignored.
-	gcMarkWorkerNotWorker gcMarkWorkerMode = iota
-
-	// gcMarkWorkerDedicatedMode indicates that the P of a mark
-	// worker is dedicated to running that mark worker. The mark
-	// worker should run without preemption.
-	gcMarkWorkerDedicatedMode
-
-	// gcMarkWorkerFractionalMode indicates that a P is currently
-	// running the "fractional" mark worker. The fractional worker
-	// is necessary when GOMAXPROCS*gcBackgroundUtilization is not
-	// an integer and using only dedicated workers would result in
-	// utilization too far from the target of gcBackgroundUtilization.
-	// The fractional worker should run until it is preempted and
-	// will be scheduled to pick up the fractional part of
-	// GOMAXPROCS*gcBackgroundUtilization.
-	gcMarkWorkerFractionalMode
-
-	// gcMarkWorkerIdleMode indicates that a P is running the mark
-	// worker because it has nothing else to do. The idle worker
-	// should run until it is preempted and account its time
-	// against gcController.idleMarkTime.
-	gcMarkWorkerIdleMode
-)
-
-// gcMarkWorkerModeStrings are the strings labels of gcMarkWorkerModes
-// to use in execution traces.
-var gcMarkWorkerModeStrings = [...]string{
-	"Not worker",
-	"GC (dedicated)",
-	"GC (fractional)",
-	"GC (idle)",
-}
-
-// pollFractionalWorkerExit reports whether a fractional mark worker
-// should self-preempt. It assumes it is called from the fractional
-// worker.
-func pollFractionalWorkerExit() bool {
-	// This should be kept in sync with the fractional worker
-	// scheduler logic in findRunnableGCWorker.
-	now := nanotime()
-	delta := now - gcController.markStartTime
-	if delta <= 0 {
-		return true
-	}
-	p := getg().m.p.ptr()
-	selfTime := p.gcFractionalMarkTime + (now - p.gcMarkWorkerStartTime)
-	// Add some slack to the utilization goal so that the
-	// fractional worker isn't behind again the instant it exits.
-	return float64(selfTime)/float64(delta) > 1.2*gcController.fractionalUtilizationGoal
-}
-
-var work struct {
-	full  lfstack          // lock-free list of full blocks workbuf
-	empty lfstack          // lock-free list of empty blocks workbuf
-	pad0  cpu.CacheLinePad // prevents false-sharing between full/empty and nproc/nwait
-
-	wbufSpans struct {
-		lock mutex
-		// free is a list of spans dedicated to workbufs, but
-		// that don't currently contain any workbufs.
-		free mSpanList
-		// busy is a list of all spans containing workbufs on
-		// one of the workbuf lists.
-		busy mSpanList
-	}
-
-	// Restore 64-bit alignment on 32-bit.
-	_ uint32
-
-	// bytesMarked is the number of bytes marked this cycle. This
-	// includes bytes blackened in scanned objects, noscan objects
-	// that go straight to black, and permagrey objects scanned by
-	// markroot during the concurrent scan phase. This is updated
-	// atomically during the cycle. Updates may be batched
-	// arbitrarily, since the value is only read at the end of the
-	// cycle.
-	//
-	// Because of benign races during marking, this number may not
-	// be the exact number of marked bytes, but it should be very
-	// close.
-	//
-	// Put this field here because it needs 64-bit atomic access
-	// (and thus 8-byte alignment even on 32-bit architectures).
-	bytesMarked uint64
-
-	markrootNext uint32 // next markroot job
-	markrootJobs uint32 // number of markroot jobs
-
-	nproc  uint32
-	tstart int64
-	nwait  uint32
-
-	// Number of roots of various root types. Set by gcMarkRootPrepare.
-	//
-	// nStackRoots == len(stackRoots), but we have nStackRoots for
-	// consistency.
-	nDataRoots, nBSSRoots, nSpanRoots, nStackRoots int
-
-	// Base indexes of each root type. Set by gcMarkRootPrepare.
-	baseData, baseBSS, baseSpans, baseStacks, baseEnd uint32
-
-	// stackRoots is a snapshot of all of the Gs that existed
-	// before the beginning of concurrent marking. The backing
-	// store of this must not be modified because it might be
-	// shared with allgs.
-	stackRoots []*g
-
-	// Each type of GC state transition is protected by a lock.
-	// Since multiple threads can simultaneously detect the state
-	// transition condition, any thread that detects a transition
-	// condition must acquire the appropriate transition lock,
-	// re-check the transition condition and return if it no
-	// longer holds or perform the transition if it does.
-	// Likewise, any transition must invalidate the transition
-	// condition before releasing the lock. This ensures that each
-	// transition is performed by exactly one thread and threads
-	// that need the transition to happen block until it has
-	// happened.
-	//
-	// startSema protects the transition from "off" to mark or
-	// mark termination.
-	startSema uint32
-	// markDoneSema protects transitions from mark to mark termination.
-	markDoneSema uint32
-
-	bgMarkReady note   // signal background mark worker has started
-	bgMarkDone  uint32 // cas to 1 when at a background mark completion point
-	// Background mark completion signaling
-
-	// mode is the concurrency mode of the current GC cycle.
-	mode gcMode
-
-	// userForced indicates the current GC cycle was forced by an
-	// explicit user call.
-	userForced bool
-
-	// totaltime is the CPU nanoseconds spent in GC since the
-	// program started if debug.gctrace > 0.
-	totaltime int64
-
-	// initialHeapLive is the value of gcController.heapLive at the
-	// beginning of this GC cycle.
-	initialHeapLive uint64
-
-	// assistQueue is a queue of assists that are blocked because
-	// there was neither enough credit to steal or enough work to
-	// do.
-	assistQueue struct {
-		lock mutex
-		q    gQueue
-	}
-
-	// sweepWaiters is a list of blocked goroutines to wake when
-	// we transition from mark termination to sweep.
-	sweepWaiters struct {
-		lock mutex
-		list gList
-	}
-
-	// cycles is the number of completed GC cycles, where a GC
-	// cycle is sweep termination, mark, mark termination, and
-	// sweep. This differs from memstats.numgc, which is
-	// incremented at mark termination.
-	cycles uint32
-
-	// Timing/utilization stats for this cycle.
-	stwprocs, maxprocs                 int32
-	tSweepTerm, tMark, tMarkTerm, tEnd int64 // nanotime() of phase start
-
-	pauseNS    int64 // total STW time this cycle
-	pauseStart int64 // nanotime() of last STW
-
-	// debug.gctrace heap sizes for this cycle.
-	heap0, heap1, heap2, heapGoal uint64
-}
-
-// GC runs a garbage collection and blocks the caller until the
-// garbage collection is complete. It may also block the entire
-// program.
-func GC() {
-	// We consider a cycle to be: sweep termination, mark, mark
-	// termination, and sweep. This function shouldn't return
-	// until a full cycle has been completed, from beginning to
-	// end. Hence, we always want to finish up the current cycle
-	// and start a new one. That means:
-	//
-	// 1. In sweep termination, mark, or mark termination of cycle
-	// N, wait until mark termination N completes and transitions
-	// to sweep N.
-	//
-	// 2. In sweep N, help with sweep N.
-	//
-	// At this point we can begin a full cycle N+1.
-	//
-	// 3. Trigger cycle N+1 by starting sweep termination N+1.
-	//
-	// 4. Wait for mark termination N+1 to complete.
-	//
-	// 5. Help with sweep N+1 until it's done.
-	//
-	// This all has to be written to deal with the fact that the
-	// GC may move ahead on its own. For example, when we block
-	// until mark termination N, we may wake up in cycle N+2.
-
-	// Wait until the current sweep termination, mark, and mark
-	// termination complete.
-	n := atomic.Load(&work.cycles)
-	gcWaitOnMark(n)
-
-	// We're now in sweep N or later. Trigger GC cycle N+1, which
-	// will first finish sweep N if necessary and then enter sweep
-	// termination N+1.
-	gcStart(gcTrigger{kind: gcTriggerCycle, n: n + 1})
-
-	// Wait for mark termination N+1 to complete.
-	gcWaitOnMark(n + 1)
-
-	// Finish sweep N+1 before returning. We do this both to
-	// complete the cycle and because runtime.GC() is often used
-	// as part of tests and benchmarks to get the system into a
-	// relatively stable and isolated state.
-	for atomic.Load(&work.cycles) == n+1 && sweepone() != ^uintptr(0) {
-		sweep.nbgsweep++
-		Gosched()
-	}
-
-	// Callers may assume that the heap profile reflects the
-	// just-completed cycle when this returns (historically this
-	// happened because this was a STW GC), but right now the
-	// profile still reflects mark termination N, not N+1.
-	//
-	// As soon as all of the sweep frees from cycle N+1 are done,
-	// we can go ahead and publish the heap profile.
-	//
-	// First, wait for sweeping to finish. (We know there are no
-	// more spans on the sweep queue, but we may be concurrently
-	// sweeping spans, so we have to wait.)
-	for atomic.Load(&work.cycles) == n+1 && !isSweepDone() {
-		Gosched()
-	}
-
-	// Now we're really done with sweeping, so we can publish the
-	// stable heap profile. Only do this if we haven't already hit
-	// another mark termination.
-	mp := acquirem()
-	cycle := atomic.Load(&work.cycles)
-	if cycle == n+1 || (gcphase == _GCmark && cycle == n+2) {
-		mProf_PostSweep()
-	}
-	releasem(mp)
-}
-
-// gcWaitOnMark blocks until GC finishes the Nth mark phase. If GC has
-// already completed this mark phase, it returns immediately.
-func gcWaitOnMark(n uint32) {
-	for {
-		// Disable phase transitions.
-		lock(&work.sweepWaiters.lock)
-		nMarks := atomic.Load(&work.cycles)
-		if gcphase != _GCmark {
-			// We've already completed this cycle's mark.
-			nMarks++
-		}
-		if nMarks > n {
-			// We're done.
-			unlock(&work.sweepWaiters.lock)
-			return
-		}
-
-		// Wait until sweep termination, mark, and mark
-		// termination of cycle N complete.
-		work.sweepWaiters.list.push(getg())
-		goparkunlock(&work.sweepWaiters.lock, waitReasonWaitForGCCycle, traceEvGoBlock, 1)
-	}
-}
-
-// gcMode indicates how concurrent a GC cycle should be.
-type gcMode int
-
-const (
-	gcBackgroundMode gcMode = iota // concurrent GC and sweep
-	gcForceMode                    // stop-the-world GC now, concurrent sweep
-	gcForceBlockMode               // stop-the-world GC now and STW sweep (forced by user)
-)
-
-// A gcTrigger is a predicate for starting a GC cycle. Specifically,
-// it is an exit condition for the _GCoff phase.
-type gcTrigger struct {
-	kind gcTriggerKind
-	now  int64  // gcTriggerTime: current time
-	n    uint32 // gcTriggerCycle: cycle number to start
-}
-
-type gcTriggerKind int
-
-const (
-	// gcTriggerHeap indicates that a cycle should be started when
-	// the heap size reaches the trigger heap size computed by the
-	// controller.
-	gcTriggerHeap gcTriggerKind = iota
-
-	// gcTriggerTime indicates that a cycle should be started when
-	// it's been more than forcegcperiod nanoseconds since the
-	// previous GC cycle.
-	gcTriggerTime
-
-	// gcTriggerCycle indicates that a cycle should be started if
-	// we have not yet started cycle number gcTrigger.n (relative
-	// to work.cycles).
-	gcTriggerCycle
-)
-
-// test reports whether the trigger condition is satisfied, meaning
-// that the exit condition for the _GCoff phase has been met. The exit
-// condition should be tested when allocating.
-func (t gcTrigger) test() bool {
-	if !memstats.enablegc || panicking != 0 || gcphase != _GCoff {
-		return false
-	}
-	switch t.kind {
-	case gcTriggerHeap:
-		// Non-atomic access to gcController.heapLive for performance. If
-		// we are going to trigger on this, this thread just
-		// atomically wrote gcController.heapLive anyway and we'll see our
-		// own write.
-		return gcController.heapLive >= gcController.trigger
-	case gcTriggerTime:
-		if gcController.gcPercent.Load() < 0 {
-			return false
-		}
-		lastgc := int64(atomic.Load64(&memstats.last_gc_nanotime))
-		return lastgc != 0 && t.now-lastgc > forcegcperiod
-	case gcTriggerCycle:
-		// t.n > work.cycles, but accounting for wraparound.
-		return int32(t.n-work.cycles) > 0
-	}
-	return true
-}
-
-// gcStart starts the GC. It transitions from _GCoff to _GCmark (if
-// debug.gcstoptheworld == 0) or performs all of GC (if
-// debug.gcstoptheworld != 0).
-//
-// This may return without performing this transition in some cases,
-// such as when called on a system stack or with locks held.
-func gcStart(trigger gcTrigger) {
-	// Since this is called from malloc and malloc is called in
-	// the guts of a number of libraries that might be holding
-	// locks, don't attempt to start GC in non-preemptible or
-	// potentially unstable situations.
-	mp := acquirem()
-	if gp := getg(); gp == mp.g0 || mp.locks > 1 || mp.preemptoff != "" {
-		releasem(mp)
-		return
-	}
-	releasem(mp)
-	mp = nil
-
-	// Pick up the remaining unswept/not being swept spans concurrently
-	//
-	// This shouldn't happen if we're being invoked in background
-	// mode since proportional sweep should have just finished
-	// sweeping everything, but rounding errors, etc, may leave a
-	// few spans unswept. In forced mode, this is necessary since
-	// GC can be forced at any point in the sweeping cycle.
-	//
-	// We check the transition condition continuously here in case
-	// this G gets delayed in to the next GC cycle.
-	for trigger.test() && sweepone() != ^uintptr(0) {
-		sweep.nbgsweep++
-	}
-
-	// Perform GC initialization and the sweep termination
-	// transition.
-	semacquire(&work.startSema)
-	// Re-check transition condition under transition lock.
-	if !trigger.test() {
-		semrelease(&work.startSema)
-		return
-	}
-
-	// For stats, check if this GC was forced by the user.
-	work.userForced = trigger.kind == gcTriggerCycle
-
-	// In gcstoptheworld debug mode, upgrade the mode accordingly.
-	// We do this after re-checking the transition condition so
-	// that multiple goroutines that detect the heap trigger don't
-	// start multiple STW GCs.
-	mode := gcBackgroundMode
-	if debug.gcstoptheworld == 1 {
-		mode = gcForceMode
-	} else if debug.gcstoptheworld == 2 {
-		mode = gcForceBlockMode
-	}
-
-	// Ok, we're doing it! Stop everybody else
-	semacquire(&gcsema)
-	semacquire(&worldsema)
-
-	if trace.enabled {
-		traceGCStart()
-	}
-
-	// Check that all Ps have finished deferred mcache flushes.
-	for _, p := range allp {
-		if fg := atomic.Load(&p.mcache.flushGen); fg != mheap_.sweepgen {
-			println("runtime: p", p.id, "flushGen", fg, "!= sweepgen", mheap_.sweepgen)
-			throw("p mcache not flushed")
-		}
-	}
-
-	gcBgMarkStartWorkers()
-
-	systemstack(gcResetMarkState)
-
-	work.stwprocs, work.maxprocs = gomaxprocs, gomaxprocs
-	if work.stwprocs > ncpu {
-		// This is used to compute CPU time of the STW phases,
-		// so it can't be more than ncpu, even if GOMAXPROCS is.
-		work.stwprocs = ncpu
-	}
-	work.heap0 = atomic.Load64(&gcController.heapLive)
-	work.pauseNS = 0
-	work.mode = mode
-
-	now := nanotime()
-	work.tSweepTerm = now
-	work.pauseStart = now
-	if trace.enabled {
-		traceGCSTWStart(1)
-	}
-	systemstack(stopTheWorldWithSema)
-	// Finish sweep before we start concurrent scan.
-	systemstack(func() {
-		finishsweep_m()
-	})
-
-	// clearpools before we start the GC. If we wait they memory will not be
-	// reclaimed until the next GC cycle.
-	clearpools()
-
-	work.cycles++
-
-	// Assists and workers can start the moment we start
-	// the world.
-	gcController.startCycle(now, int(gomaxprocs))
-	work.heapGoal = gcController.heapGoal
-
-	// In STW mode, disable scheduling of user Gs. This may also
-	// disable scheduling of this goroutine, so it may block as
-	// soon as we start the world again.
-	if mode != gcBackgroundMode {
-		schedEnableUser(false)
-	}
-
-	// Enter concurrent mark phase and enable
-	// write barriers.
-	//
-	// Because the world is stopped, all Ps will
-	// observe that write barriers are enabled by
-	// the time we start the world and begin
-	// scanning.
-	//
-	// Write barriers must be enabled before assists are
-	// enabled because they must be enabled before
-	// any non-leaf heap objects are marked. Since
-	// allocations are blocked until assists can
-	// happen, we want enable assists as early as
-	// possible.
-	setGCPhase(_GCmark)
-
-	gcBgMarkPrepare() // Must happen before assist enable.
-	gcMarkRootPrepare()
-
-	// Mark all active tinyalloc blocks. Since we're
-	// allocating from these, they need to be black like
-	// other allocations. The alternative is to blacken
-	// the tiny block on every allocation from it, which
-	// would slow down the tiny allocator.
-	gcMarkTinyAllocs()
-
-	// At this point all Ps have enabled the write
-	// barrier, thus maintaining the no white to
-	// black invariant. Enable mutator assists to
-	// put back-pressure on fast allocating
-	// mutators.
-	atomic.Store(&gcBlackenEnabled, 1)
-
-	// In STW mode, we could block the instant systemstack
-	// returns, so make sure we're not preemptible.
-	mp = acquirem()
-
-	// Concurrent mark.
-	systemstack(func() {
-		now = startTheWorldWithSema(trace.enabled)
-		work.pauseNS += now - work.pauseStart
-		work.tMark = now
-		memstats.gcPauseDist.record(now - work.pauseStart)
-	})
-
-	// Release the world sema before Gosched() in STW mode
-	// because we will need to reacquire it later but before
-	// this goroutine becomes runnable again, and we could
-	// self-deadlock otherwise.
-	semrelease(&worldsema)
-	releasem(mp)
-
-	// Make sure we block instead of returning to user code
-	// in STW mode.
-	if mode != gcBackgroundMode {
-		Gosched()
-	}
-
-	semrelease(&work.startSema)
-}
-
-// gcMarkDoneFlushed counts the number of P's with flushed work.
-//
-// Ideally this would be a captured local in gcMarkDone, but forEachP
-// escapes its callback closure, so it can't capture anything.
-//
-// This is protected by markDoneSema.
-var gcMarkDoneFlushed uint32
-
-// gcMarkDone transitions the GC from mark to mark termination if all
-// reachable objects have been marked (that is, there are no grey
-// objects and can be no more in the future). Otherwise, it flushes
-// all local work to the global queues where it can be discovered by
-// other workers.
-//
-// This should be called when all local mark work has been drained and
-// there are no remaining workers. Specifically, when
-//
-//   work.nwait == work.nproc && !gcMarkWorkAvailable(p)
-//
-// The calling context must be preemptible.
-//
-// Flushing local work is important because idle Ps may have local
-// work queued. This is the only way to make that work visible and
-// drive GC to completion.
-//
-// It is explicitly okay to have write barriers in this function. If
-// it does transition to mark termination, then all reachable objects
-// have been marked, so the write barrier cannot shade any more
-// objects.
-func gcMarkDone() {
-	// Ensure only one thread is running the ragged barrier at a
-	// time.
-	semacquire(&work.markDoneSema)
-
-top:
-	// Re-check transition condition under transition lock.
-	//
-	// It's critical that this checks the global work queues are
-	// empty before performing the ragged barrier. Otherwise,
-	// there could be global work that a P could take after the P
-	// has passed the ragged barrier.
-	if !(gcphase == _GCmark && work.nwait == work.nproc && !gcMarkWorkAvailable(nil)) {
-		semrelease(&work.markDoneSema)
-		return
-	}
-
-	// forEachP needs worldsema to execute, and we'll need it to
-	// stop the world later, so acquire worldsema now.
-	semacquire(&worldsema)
-
-	// Flush all local buffers and collect flushedWork flags.
-	gcMarkDoneFlushed = 0
-	systemstack(func() {
-		gp := getg().m.curg
-		// Mark the user stack as preemptible so that it may be scanned.
-		// Otherwise, our attempt to force all P's to a safepoint could
-		// result in a deadlock as we attempt to preempt a worker that's
-		// trying to preempt us (e.g. for a stack scan).
-		casgstatus(gp, _Grunning, _Gwaiting)
-		forEachP(func(_p_ *p) {
-			// Flush the write barrier buffer, since this may add
-			// work to the gcWork.
-			wbBufFlush1(_p_)
-
-			// Flush the gcWork, since this may create global work
-			// and set the flushedWork flag.
-			//
-			// TODO(austin): Break up these workbufs to
-			// better distribute work.
-			_p_.gcw.dispose()
-			// Collect the flushedWork flag.
-			if _p_.gcw.flushedWork {
-				atomic.Xadd(&gcMarkDoneFlushed, 1)
-				_p_.gcw.flushedWork = false
-			}
-		})
-		casgstatus(gp, _Gwaiting, _Grunning)
-	})
-
-	if gcMarkDoneFlushed != 0 {
-		// More grey objects were discovered since the
-		// previous termination check, so there may be more
-		// work to do. Keep going. It's possible the
-		// transition condition became true again during the
-		// ragged barrier, so re-check it.
-		semrelease(&worldsema)
-		goto top
-	}
-
-	// There was no global work, no local work, and no Ps
-	// communicated work since we took markDoneSema. Therefore
-	// there are no grey objects and no more objects can be
-	// shaded. Transition to mark termination.
-	now := nanotime()
-	work.tMarkTerm = now
-	work.pauseStart = now
-	getg().m.preemptoff = "gcing"
-	if trace.enabled {
-		traceGCSTWStart(0)
-	}
-	systemstack(stopTheWorldWithSema)
-	// The gcphase is _GCmark, it will transition to _GCmarktermination
-	// below. The important thing is that the wb remains active until
-	// all marking is complete. This includes writes made by the GC.
-
-	// There is sometimes work left over when we enter mark termination due
-	// to write barriers performed after the completion barrier above.
-	// Detect this and resume concurrent mark. This is obviously
-	// unfortunate.
-	//
-	// See issue #27993 for details.
-	//
-	// Switch to the system stack to call wbBufFlush1, though in this case
-	// it doesn't matter because we're non-preemptible anyway.
-	restart := false
-	systemstack(func() {
-		for _, p := range allp {
-			wbBufFlush1(p)
-			if !p.gcw.empty() {
-				restart = true
-				break
-			}
-		}
-	})
-	if restart {
-		getg().m.preemptoff = ""
-		systemstack(func() {
-			now := startTheWorldWithSema(true)
-			work.pauseNS += now - work.pauseStart
-			memstats.gcPauseDist.record(now - work.pauseStart)
-		})
-		semrelease(&worldsema)
-		goto top
-	}
-
-	// Disable assists and background workers. We must do
-	// this before waking blocked assists.
-	atomic.Store(&gcBlackenEnabled, 0)
-
-	// Wake all blocked assists. These will run when we
-	// start the world again.
-	gcWakeAllAssists()
-
-	// Likewise, release the transition lock. Blocked
-	// workers and assists will run when we start the
-	// world again.
-	semrelease(&work.markDoneSema)
-
-	// In STW mode, re-enable user goroutines. These will be
-	// queued to run after we start the world.
-	schedEnableUser(true)
-
-	// endCycle depends on all gcWork cache stats being flushed.
-	// The termination algorithm above ensured that up to
-	// allocations since the ragged barrier.
-	nextTriggerRatio := gcController.endCycle(now, int(gomaxprocs), work.userForced)
-
-	// Perform mark termination. This will restart the world.
-	gcMarkTermination(nextTriggerRatio)
-}
-
-// World must be stopped and mark assists and background workers must be
-// disabled.
-func gcMarkTermination(nextTriggerRatio float64) {
-	// Start marktermination (write barrier remains enabled for now).
-	setGCPhase(_GCmarktermination)
-
-	work.heap1 = gcController.heapLive
-	startTime := nanotime()
-
-	mp := acquirem()
-	mp.preemptoff = "gcing"
-	_g_ := getg()
-	_g_.m.traceback = 2
-	gp := _g_.m.curg
-	casgstatus(gp, _Grunning, _Gwaiting)
-	gp.waitreason = waitReasonGarbageCollection
-
-	// Run gc on the g0 stack. We do this so that the g stack
-	// we're currently running on will no longer change. Cuts
-	// the root set down a bit (g0 stacks are not scanned, and
-	// we don't need to scan gc's internal state).  We also
-	// need to switch to g0 so we can shrink the stack.
-	systemstack(func() {
-		gcMark(startTime)
-		// Must return immediately.
-		// The outer function's stack may have moved
-		// during gcMark (it shrinks stacks, including the
-		// outer function's stack), so we must not refer
-		// to any of its variables. Return back to the
-		// non-system stack to pick up the new addresses
-		// before continuing.
-	})
-
-	systemstack(func() {
-		work.heap2 = work.bytesMarked
-		if debug.gccheckmark > 0 {
-			// Run a full non-parallel, stop-the-world
-			// mark using checkmark bits, to check that we
-			// didn't forget to mark anything during the
-			// concurrent mark process.
-			startCheckmarks()
-			gcResetMarkState()
-			gcw := &getg().m.p.ptr().gcw
-			gcDrain(gcw, 0)
-			wbBufFlush1(getg().m.p.ptr())
-			gcw.dispose()
-			endCheckmarks()
-		}
-
-		// marking is complete so we can turn the write barrier off
-		setGCPhase(_GCoff)
-		gcSweep(work.mode)
-	})
-
-	_g_.m.traceback = 0
-	casgstatus(gp, _Gwaiting, _Grunning)
-
-	if trace.enabled {
-		traceGCDone()
-	}
-
-	// all done
-	mp.preemptoff = ""
-
-	if gcphase != _GCoff {
-		throw("gc done but gcphase != _GCoff")
-	}
-
-	// Record heap_inuse for scavenger.
-	memstats.last_heap_inuse = memstats.heap_inuse
-
-	// Update GC trigger and pacing for the next cycle.
-	gcController.commit(nextTriggerRatio)
-	gcPaceSweeper(gcController.trigger)
-	gcPaceScavenger(gcController.heapGoal, gcController.lastHeapGoal)
-
-	// Update timing memstats
-	now := nanotime()
-	sec, nsec, _ := time_now()
-	unixNow := sec*1e9 + int64(nsec)
-	work.pauseNS += now - work.pauseStart
-	work.tEnd = now
-	memstats.gcPauseDist.record(now - work.pauseStart)
-	atomic.Store64(&memstats.last_gc_unix, uint64(unixNow)) // must be Unix time to make sense to user
-	atomic.Store64(&memstats.last_gc_nanotime, uint64(now)) // monotonic time for us
-	memstats.pause_ns[memstats.numgc%uint32(len(memstats.pause_ns))] = uint64(work.pauseNS)
-	memstats.pause_end[memstats.numgc%uint32(len(memstats.pause_end))] = uint64(unixNow)
-	memstats.pause_total_ns += uint64(work.pauseNS)
-
-	// Update work.totaltime.
-	sweepTermCpu := int64(work.stwprocs) * (work.tMark - work.tSweepTerm)
-	// We report idle marking time below, but omit it from the
-	// overall utilization here since it's "free".
-	markCpu := gcController.assistTime + gcController.dedicatedMarkTime + gcController.fractionalMarkTime
-	markTermCpu := int64(work.stwprocs) * (work.tEnd - work.tMarkTerm)
-	cycleCpu := sweepTermCpu + markCpu + markTermCpu
-	work.totaltime += cycleCpu
-
-	// Compute overall GC CPU utilization.
-	totalCpu := sched.totaltime + (now-sched.procresizetime)*int64(gomaxprocs)
-	memstats.gc_cpu_fraction = float64(work.totaltime) / float64(totalCpu)
-
-	// Reset sweep state.
-	sweep.nbgsweep = 0
-	sweep.npausesweep = 0
-
-	if work.userForced {
-		memstats.numforcedgc++
-	}
-
-	// Bump GC cycle count and wake goroutines waiting on sweep.
-	lock(&work.sweepWaiters.lock)
-	memstats.numgc++
-	injectglist(&work.sweepWaiters.list)
-	unlock(&work.sweepWaiters.lock)
-
-	// Finish the current heap profiling cycle and start a new
-	// heap profiling cycle. We do this before starting the world
-	// so events don't leak into the wrong cycle.
-	mProf_NextCycle()
-
-	// There may be stale spans in mcaches that need to be swept.
-	// Those aren't tracked in any sweep lists, so we need to
-	// count them against sweep completion until we ensure all
-	// those spans have been forced out.
-	sl := sweep.active.begin()
-	if !sl.valid {
-		throw("failed to set sweep barrier")
-	}
-
-	systemstack(func() { startTheWorldWithSema(true) })
-
-	// Flush the heap profile so we can start a new cycle next GC.
-	// This is relatively expensive, so we don't do it with the
-	// world stopped.
-	mProf_Flush()
-
-	// Prepare workbufs for freeing by the sweeper. We do this
-	// asynchronously because it can take non-trivial time.
-	prepareFreeWorkbufs()
-
-	// Free stack spans. This must be done between GC cycles.
-	systemstack(freeStackSpans)
-
-	// Ensure all mcaches are flushed. Each P will flush its own
-	// mcache before allocating, but idle Ps may not. Since this
-	// is necessary to sweep all spans, we need to ensure all
-	// mcaches are flushed before we start the next GC cycle.
-	systemstack(func() {
-		forEachP(func(_p_ *p) {
-			_p_.mcache.prepareForSweep()
-		})
-	})
-	// Now that we've swept stale spans in mcaches, they don't
-	// count against unswept spans.
-	sweep.active.end(sl)
-
-	// Print gctrace before dropping worldsema. As soon as we drop
-	// worldsema another cycle could start and smash the stats
-	// we're trying to print.
-	if debug.gctrace > 0 {
-		util := int(memstats.gc_cpu_fraction * 100)
-
-		var sbuf [24]byte
-		printlock()
-		print("gc ", memstats.numgc,
-			" @", string(itoaDiv(sbuf[:], uint64(work.tSweepTerm-runtimeInitTime)/1e6, 3)), "s ",
-			util, "%: ")
-		prev := work.tSweepTerm
-		for i, ns := range []int64{work.tMark, work.tMarkTerm, work.tEnd} {
-			if i != 0 {
-				print("+")
-			}
-			print(string(fmtNSAsMS(sbuf[:], uint64(ns-prev))))
-			prev = ns
-		}
-		print(" ms clock, ")
-		for i, ns := range []int64{sweepTermCpu, gcController.assistTime, gcController.dedicatedMarkTime + gcController.fractionalMarkTime, gcController.idleMarkTime, markTermCpu} {
-			if i == 2 || i == 3 {
-				// Separate mark time components with /.
-				print("/")
-			} else if i != 0 {
-				print("+")
-			}
-			print(string(fmtNSAsMS(sbuf[:], uint64(ns))))
-		}
-		print(" ms cpu, ",
-			work.heap0>>20, "->", work.heap1>>20, "->", work.heap2>>20, " MB, ",
-			work.heapGoal>>20, " MB goal, ",
-			gcController.stackScan>>20, " MB stacks, ",
-			gcController.globalsScan>>20, " MB globals, ",
-			work.maxprocs, " P")
-		if work.userForced {
-			print(" (forced)")
-		}
-		print("\n")
-		printunlock()
-	}
-
-	semrelease(&worldsema)
-	semrelease(&gcsema)
-	// Careful: another GC cycle may start now.
-
-	releasem(mp)
-	mp = nil
-
-	// now that gc is done, kick off finalizer thread if needed
-	if !concurrentSweep {
-		// give the queued finalizers, if any, a chance to run
-		Gosched()
-	}
-}
-
-// gcBgMarkStartWorkers prepares background mark worker goroutines. These
-// goroutines will not run until the mark phase, but they must be started while
-// the work is not stopped and from a regular G stack. The caller must hold
-// worldsema.
-func gcBgMarkStartWorkers() {
-	// Background marking is performed by per-P G's. Ensure that each P has
-	// a background GC G.
-	//
-	// Worker Gs don't exit if gomaxprocs is reduced. If it is raised
-	// again, we can reuse the old workers; no need to create new workers.
-	for gcBgMarkWorkerCount < gomaxprocs {
-		go gcBgMarkWorker()
-
-		notetsleepg(&work.bgMarkReady, -1)
-		noteclear(&work.bgMarkReady)
-		// The worker is now guaranteed to be added to the pool before
-		// its P's next findRunnableGCWorker.
-
-		gcBgMarkWorkerCount++
-	}
-}
-
-// gcBgMarkPrepare sets up state for background marking.
-// Mutator assists must not yet be enabled.
-func gcBgMarkPrepare() {
-	// Background marking will stop when the work queues are empty
-	// and there are no more workers (note that, since this is
-	// concurrent, this may be a transient state, but mark
-	// termination will clean it up). Between background workers
-	// and assists, we don't really know how many workers there
-	// will be, so we pretend to have an arbitrarily large number
-	// of workers, almost all of which are "waiting". While a
-	// worker is working it decrements nwait. If nproc == nwait,
-	// there are no workers.
-	work.nproc = ^uint32(0)
-	work.nwait = ^uint32(0)
-}
-
-// gcBgMarkWorker is an entry in the gcBgMarkWorkerPool. It points to a single
-// gcBgMarkWorker goroutine.
-type gcBgMarkWorkerNode struct {
-	// Unused workers are managed in a lock-free stack. This field must be first.
-	node lfnode
-
-	// The g of this worker.
-	gp guintptr
-
-	// Release this m on park. This is used to communicate with the unlock
-	// function, which cannot access the G's stack. It is unused outside of
-	// gcBgMarkWorker().
-	m muintptr
-}
-
-func gcBgMarkWorker() {
-	gp := getg()
-
-	// We pass node to a gopark unlock function, so it can't be on
-	// the stack (see gopark). Prevent deadlock from recursively
-	// starting GC by disabling preemption.
-	gp.m.preemptoff = "GC worker init"
-	node := new(gcBgMarkWorkerNode)
-	gp.m.preemptoff = ""
-
-	node.gp.set(gp)
-
-	node.m.set(acquirem())
-	notewakeup(&work.bgMarkReady)
-	// After this point, the background mark worker is generally scheduled
-	// cooperatively by gcController.findRunnableGCWorker. While performing
-	// work on the P, preemption is disabled because we are working on
-	// P-local work buffers. When the preempt flag is set, this puts itself
-	// into _Gwaiting to be woken up by gcController.findRunnableGCWorker
-	// at the appropriate time.
-	//
-	// When preemption is enabled (e.g., while in gcMarkDone), this worker
-	// may be preempted and schedule as a _Grunnable G from a runq. That is
-	// fine; it will eventually gopark again for further scheduling via
-	// findRunnableGCWorker.
-	//
-	// Since we disable preemption before notifying bgMarkReady, we
-	// guarantee that this G will be in the worker pool for the next
-	// findRunnableGCWorker. This isn't strictly necessary, but it reduces
-	// latency between _GCmark starting and the workers starting.
-
-	for {
-		// Go to sleep until woken by
-		// gcController.findRunnableGCWorker.
-		gopark(func(g *g, nodep unsafe.Pointer) bool {
-			node := (*gcBgMarkWorkerNode)(nodep)
-
-			if mp := node.m.ptr(); mp != nil {
-				// The worker G is no longer running; release
-				// the M.
-				//
-				// N.B. it is _safe_ to release the M as soon
-				// as we are no longer performing P-local mark
-				// work.
-				//
-				// However, since we cooperatively stop work
-				// when gp.preempt is set, if we releasem in
-				// the loop then the following call to gopark
-				// would immediately preempt the G. This is
-				// also safe, but inefficient: the G must
-				// schedule again only to enter gopark and park
-				// again. Thus, we defer the release until
-				// after parking the G.
-				releasem(mp)
-			}
-
-			// Release this G to the pool.
-			gcBgMarkWorkerPool.push(&node.node)
-			// Note that at this point, the G may immediately be
-			// rescheduled and may be running.
-			return true
-		}, unsafe.Pointer(node), waitReasonGCWorkerIdle, traceEvGoBlock, 0)
-
-		// Preemption must not occur here, or another G might see
-		// p.gcMarkWorkerMode.
-
-		// Disable preemption so we can use the gcw. If the
-		// scheduler wants to preempt us, we'll stop draining,
-		// dispose the gcw, and then preempt.
-		node.m.set(acquirem())
-		pp := gp.m.p.ptr() // P can't change with preemption disabled.
-
-		if gcBlackenEnabled == 0 {
-			println("worker mode", pp.gcMarkWorkerMode)
-			throw("gcBgMarkWorker: blackening not enabled")
-		}
-
-		if pp.gcMarkWorkerMode == gcMarkWorkerNotWorker {
-			throw("gcBgMarkWorker: mode not set")
-		}
-
-		startTime := nanotime()
-		pp.gcMarkWorkerStartTime = startTime
-
-		decnwait := atomic.Xadd(&work.nwait, -1)
-		if decnwait == work.nproc {
-			println("runtime: work.nwait=", decnwait, "work.nproc=", work.nproc)
-			throw("work.nwait was > work.nproc")
-		}
-
-		systemstack(func() {
-			// Mark our goroutine preemptible so its stack
-			// can be scanned. This lets two mark workers
-			// scan each other (otherwise, they would
-			// deadlock). We must not modify anything on
-			// the G stack. However, stack shrinking is
-			// disabled for mark workers, so it is safe to
-			// read from the G stack.
-			casgstatus(gp, _Grunning, _Gwaiting)
-			switch pp.gcMarkWorkerMode {
-			default:
-				throw("gcBgMarkWorker: unexpected gcMarkWorkerMode")
-			case gcMarkWorkerDedicatedMode:
-				gcDrain(&pp.gcw, gcDrainUntilPreempt|gcDrainFlushBgCredit)
-				if gp.preempt {
-					// We were preempted. This is
-					// a useful signal to kick
-					// everything out of the run
-					// queue so it can run
-					// somewhere else.
-					if drainQ, n := runqdrain(pp); n > 0 {
-						lock(&sched.lock)
-						globrunqputbatch(&drainQ, int32(n))
-						unlock(&sched.lock)
-					}
-				}
-				// Go back to draining, this time
-				// without preemption.
-				gcDrain(&pp.gcw, gcDrainFlushBgCredit)
-			case gcMarkWorkerFractionalMode:
-				gcDrain(&pp.gcw, gcDrainFractional|gcDrainUntilPreempt|gcDrainFlushBgCredit)
-			case gcMarkWorkerIdleMode:
-				gcDrain(&pp.gcw, gcDrainIdle|gcDrainUntilPreempt|gcDrainFlushBgCredit)
-			}
-			casgstatus(gp, _Gwaiting, _Grunning)
-		})
-
-		// Account for time.
-		duration := nanotime() - startTime
-		gcController.logWorkTime(pp.gcMarkWorkerMode, duration)
-		if pp.gcMarkWorkerMode == gcMarkWorkerFractionalMode {
-			atomic.Xaddint64(&pp.gcFractionalMarkTime, duration)
-		}
-
-		// Was this the last worker and did we run out
-		// of work?
-		incnwait := atomic.Xadd(&work.nwait, +1)
-		if incnwait > work.nproc {
-			println("runtime: p.gcMarkWorkerMode=", pp.gcMarkWorkerMode,
-				"work.nwait=", incnwait, "work.nproc=", work.nproc)
-			throw("work.nwait > work.nproc")
-		}
-
-		// We'll releasem after this point and thus this P may run
-		// something else. We must clear the worker mode to avoid
-		// attributing the mode to a different (non-worker) G in
-		// traceGoStart.
-		pp.gcMarkWorkerMode = gcMarkWorkerNotWorker
-
-		// If this worker reached a background mark completion
-		// point, signal the main GC goroutine.
-		if incnwait == work.nproc && !gcMarkWorkAvailable(nil) {
-			// We don't need the P-local buffers here, allow
-			// preemption because we may schedule like a regular
-			// goroutine in gcMarkDone (block on locks, etc).
-			releasem(node.m.ptr())
-			node.m.set(nil)
-
-			gcMarkDone()
-		}
-	}
-}
-
-// gcMarkWorkAvailable reports whether executing a mark worker
-// on p is potentially useful. p may be nil, in which case it only
-// checks the global sources of work.
-func gcMarkWorkAvailable(p *p) bool {
-	if p != nil && !p.gcw.empty() {
-		return true
-	}
-	if !work.full.empty() {
-		return true // global work available
-	}
-	if work.markrootNext < work.markrootJobs {
-		return true // root scan work available
-	}
-	return false
-}
-
-// gcMark runs the mark (or, for concurrent GC, mark termination)
-// All gcWork caches must be empty.
-// STW is in effect at this point.
-func gcMark(startTime int64) {
-	if debug.allocfreetrace > 0 {
-		tracegc()
-	}
-
-	if gcphase != _GCmarktermination {
-		throw("in gcMark expecting to see gcphase as _GCmarktermination")
-	}
-	work.tstart = startTime
-
-	// Check that there's no marking work remaining.
-	if work.full != 0 || work.markrootNext < work.markrootJobs {
-		print("runtime: full=", hex(work.full), " next=", work.markrootNext, " jobs=", work.markrootJobs, " nDataRoots=", work.nDataRoots, " nBSSRoots=", work.nBSSRoots, " nSpanRoots=", work.nSpanRoots, " nStackRoots=", work.nStackRoots, "\n")
-		panic("non-empty mark queue after concurrent mark")
-	}
-
-	if debug.gccheckmark > 0 {
-		// This is expensive when there's a large number of
-		// Gs, so only do it if checkmark is also enabled.
-		gcMarkRootCheck()
-	}
-	if work.full != 0 {
-		throw("work.full != 0")
-	}
-
-	// Drop allg snapshot. allgs may have grown, in which case
-	// this is the only reference to the old backing store and
-	// there's no need to keep it around.
-	work.stackRoots = nil
-
-	// Clear out buffers and double-check that all gcWork caches
-	// are empty. This should be ensured by gcMarkDone before we
-	// enter mark termination.
-	//
-	// TODO: We could clear out buffers just before mark if this
-	// has a non-negligible impact on STW time.
-	for _, p := range allp {
-		// The write barrier may have buffered pointers since
-		// the gcMarkDone barrier. However, since the barrier
-		// ensured all reachable objects were marked, all of
-		// these must be pointers to black objects. Hence we
-		// can just discard the write barrier buffer.
-		if debug.gccheckmark > 0 {
-			// For debugging, flush the buffer and make
-			// sure it really was all marked.
-			wbBufFlush1(p)
-		} else {
-			p.wbBuf.reset()
-		}
-
-		gcw := &p.gcw
-		if !gcw.empty() {
-			printlock()
-			print("runtime: P ", p.id, " flushedWork ", gcw.flushedWork)
-			if gcw.wbuf1 == nil {
-				print(" wbuf1=<nil>")
-			} else {
-				print(" wbuf1.n=", gcw.wbuf1.nobj)
-			}
-			if gcw.wbuf2 == nil {
-				print(" wbuf2=<nil>")
-			} else {
-				print(" wbuf2.n=", gcw.wbuf2.nobj)
-			}
-			print("\n")
-			throw("P has cached GC work at end of mark termination")
-		}
-		// There may still be cached empty buffers, which we
-		// need to flush since we're going to free them. Also,
-		// there may be non-zero stats because we allocated
-		// black after the gcMarkDone barrier.
-		gcw.dispose()
-	}
-
-	// Flush scanAlloc from each mcache since we're about to modify
-	// heapScan directly. If we were to flush this later, then scanAlloc
-	// might have incorrect information.
-	//
-	// Note that it's not important to retain this information; we know
-	// exactly what heapScan is at this point via scanWork.
-	for _, p := range allp {
-		c := p.mcache
-		if c == nil {
-			continue
-		}
-		c.scanAlloc = 0
-	}
-
-	// Reset controller state.
-	gcController.resetLive(work.bytesMarked)
-}
-
-// gcSweep must be called on the system stack because it acquires the heap
-// lock. See mheap for details.
-//
-// The world must be stopped.
-//
-//go:systemstack
-func gcSweep(mode gcMode) {
-	assertWorldStopped()
-
-	if gcphase != _GCoff {
-		throw("gcSweep being done but phase is not GCoff")
-	}
-
-	lock(&mheap_.lock)
-	mheap_.sweepgen += 2
-	sweep.active.reset()
-	mheap_.pagesSwept.Store(0)
-	mheap_.sweepArenas = mheap_.allArenas
-	mheap_.reclaimIndex.Store(0)
-	mheap_.reclaimCredit.Store(0)
-	unlock(&mheap_.lock)
-
-	sweep.centralIndex.clear()
-
-	if !_ConcurrentSweep || mode == gcForceBlockMode {
-		// Special case synchronous sweep.
-		// Record that no proportional sweeping has to happen.
-		lock(&mheap_.lock)
-		mheap_.sweepPagesPerByte = 0
-		unlock(&mheap_.lock)
-		// Sweep all spans eagerly.
-		for sweepone() != ^uintptr(0) {
-			sweep.npausesweep++
-		}
-		// Free workbufs eagerly.
-		prepareFreeWorkbufs()
-		for freeSomeWbufs(false) {
-		}
-		// All "free" events for this mark/sweep cycle have
-		// now happened, so we can make this profile cycle
-		// available immediately.
-		mProf_NextCycle()
-		mProf_Flush()
-		return
-	}
-
-	// Background sweep.
-	lock(&sweep.lock)
-	if sweep.parked {
-		sweep.parked = false
-		ready(sweep.g, 0, true)
-	}
-	unlock(&sweep.lock)
-}
-
-// gcResetMarkState resets global state prior to marking (concurrent
-// or STW) and resets the stack scan state of all Gs.
-//
-// This is safe to do without the world stopped because any Gs created
-// during or after this will start out in the reset state.
-//
-// gcResetMarkState must be called on the system stack because it acquires
-// the heap lock. See mheap for details.
-//
-//go:systemstack
-func gcResetMarkState() {
-	// This may be called during a concurrent phase, so lock to make sure
-	// allgs doesn't change.
-	forEachG(func(gp *g) {
-		gp.gcscandone = false // set to true in gcphasework
-		gp.gcAssistBytes = 0
-	})
-
-	// Clear page marks. This is just 1MB per 64GB of heap, so the
-	// time here is pretty trivial.
-	lock(&mheap_.lock)
-	arenas := mheap_.allArenas
-	unlock(&mheap_.lock)
-	for _, ai := range arenas {
-		ha := mheap_.arenas[ai.l1()][ai.l2()]
-		for i := range ha.pageMarks {
-			ha.pageMarks[i] = 0
-		}
-	}
-
-	work.bytesMarked = 0
-	work.initialHeapLive = atomic.Load64(&gcController.heapLive)
-}
-
-// Hooks for other packages
-
-var poolcleanup func()
-
-//go:linkname sync_runtime_registerPoolCleanup sync.runtime_registerPoolCleanup
-func sync_runtime_registerPoolCleanup(f func()) {
-	poolcleanup = f
-}
-
-func clearpools() {
-	// clear sync.Pools
-	if poolcleanup != nil {
-		poolcleanup()
-	}
-
-	// Clear central sudog cache.
-	// Leave per-P caches alone, they have strictly bounded size.
-	// Disconnect cached list before dropping it on the floor,
-	// so that a dangling ref to one entry does not pin all of them.
-	lock(&sched.sudoglock)
-	var sg, sgnext *sudog
-	for sg = sched.sudogcache; sg != nil; sg = sgnext {
-		sgnext = sg.next
-		sg.next = nil
-	}
-	sched.sudogcache = nil
-	unlock(&sched.sudoglock)
-
-	// Clear central defer pool.
-	// Leave per-P pools alone, they have strictly bounded size.
-	lock(&sched.deferlock)
-	// disconnect cached list before dropping it on the floor,
-	// so that a dangling ref to one entry does not pin all of them.
-	var d, dlink *_defer
-	for d = sched.deferpool; d != nil; d = dlink {
-		dlink = d.link
-		d.link = nil
-	}
-	sched.deferpool = nil
-	unlock(&sched.deferlock)
-}
-
-// Timing
-
-// itoaDiv formats val/(10**dec) into buf.
-func itoaDiv(buf []byte, val uint64, dec int) []byte {
-	i := len(buf) - 1
-	idec := i - dec
-	for val >= 10 || i >= idec {
-		buf[i] = byte(val%10 + '0')
-		i--
-		if i == idec {
-			buf[i] = '.'
-			i--
-		}
-		val /= 10
-	}
-	buf[i] = byte(val + '0')
-	return buf[i:]
-}
-
-// fmtNSAsMS nicely formats ns nanoseconds as milliseconds.
-func fmtNSAsMS(buf []byte, ns uint64) []byte {
-	if ns >= 10e6 {
-		// Format as whole milliseconds.
-		return itoaDiv(buf, ns/1e6, 0)
-	}
-	// Format two digits of precision, with at most three decimal places.
-	x := ns / 1e3
-	if x == 0 {
-		buf[0] = '0'
-		return buf[:1]
-	}
-	dec := 3
-	for x >= 100 {
-		x /= 10
-		dec--
-	}
-	return itoaDiv(buf, x, dec)
-}
-
-// Helpers for testing GC.
-
-// gcTestMoveStackOnNextCall causes the stack to be moved on a call
-// immediately following the call to this. It may not work correctly
-// if any other work appears after this call (such as returning).
-// Typically the following call should be marked go:noinline so it
-// performs a stack check.
-//
-// In rare cases this may not cause the stack to move, specifically if
-// there's a preemption between this call and the next.
-func gcTestMoveStackOnNextCall() {
-	gp := getg()
-	gp.stackguard0 = stackForceMove
-}
-
-// gcTestIsReachable performs a GC and returns a bit set where bit i
-// is set if ptrs[i] is reachable.
-func gcTestIsReachable(ptrs ...unsafe.Pointer) (mask uint64) {
-	// This takes the pointers as unsafe.Pointers in order to keep
-	// them live long enough for us to attach specials. After
-	// that, we drop our references to them.
-
-	if len(ptrs) > 64 {
-		panic("too many pointers for uint64 mask")
-	}
-
-	// Block GC while we attach specials and drop our references
-	// to ptrs. Otherwise, if a GC is in progress, it could mark
-	// them reachable via this function before we have a chance to
-	// drop them.
-	semacquire(&gcsema)
-
-	// Create reachability specials for ptrs.
-	specials := make([]*specialReachable, len(ptrs))
-	for i, p := range ptrs {
-		lock(&mheap_.speciallock)
-		s := (*specialReachable)(mheap_.specialReachableAlloc.alloc())
-		unlock(&mheap_.speciallock)
-		s.special.kind = _KindSpecialReachable
-		if !addspecial(p, &s.special) {
-			throw("already have a reachable special (duplicate pointer?)")
-		}
-		specials[i] = s
-		// Make sure we don't retain ptrs.
-		ptrs[i] = nil
-	}
-
-	semrelease(&gcsema)
-
-	// Force a full GC and sweep.
-	GC()
-
-	// Process specials.
-	for i, s := range specials {
-		if !s.done {
-			printlock()
-			println("runtime: object", i, "was not swept")
-			throw("IsReachable failed")
-		}
-		if s.reachable {
-			mask |= 1 << i
-		}
-		lock(&mheap_.speciallock)
-		mheap_.specialReachableAlloc.free(unsafe.Pointer(s))
-		unlock(&mheap_.speciallock)
-	}
-
-	return mask
-}
-
-// gcTestPointerClass returns the category of what p points to, one of:
-// "heap", "stack", "data", "bss", "other". This is useful for checking
-// that a test is doing what it's intended to do.
-//
-// This is nosplit simply to avoid extra pointer shuffling that may
-// complicate a test.
-//
-//go:nosplit
-func gcTestPointerClass(p unsafe.Pointer) string {
-	p2 := uintptr(noescape(p))
-	gp := getg()
-	if gp.stack.lo <= p2 && p2 < gp.stack.hi {
-		return "stack"
-	}
-	if base, _, _ := findObject(p2, 0, 0); base != 0 {
-		return "heap"
-	}
-	for _, datap := range activeModules() {
-		if datap.data <= p2 && p2 < datap.edata || datap.noptrdata <= p2 && p2 < datap.enoptrdata {
-			return "data"
-		}
-		if datap.bss <= p2 && p2 < datap.ebss || datap.noptrbss <= p2 && p2 <= datap.enoptrbss {
-			return "bss"
-		}
-	}
-	KeepAlive(p)
-	return "other"
-}
diff --git a/contrib/go/_std_1.18/src/runtime/mgcmark.go b/contrib/go/_std_1.18/src/runtime/mgcmark.go
deleted file mode 100644
index 0bf044e314..0000000000
--- a/contrib/go/_std_1.18/src/runtime/mgcmark.go
+++ /dev/null
@@ -1,1591 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Garbage collector: marking and scanning
-
-package runtime
-
-import (
-	"internal/goarch"
-	"internal/goexperiment"
-	"runtime/internal/atomic"
-	"runtime/internal/sys"
-	"unsafe"
-)
-
-const (
-	fixedRootFinalizers = iota
-	fixedRootFreeGStacks
-	fixedRootCount
-
-	// rootBlockBytes is the number of bytes to scan per data or
-	// BSS root.
-	rootBlockBytes = 256 << 10
-
-	// maxObletBytes is the maximum bytes of an object to scan at
-	// once. Larger objects will be split up into "oblets" of at
-	// most this size. Since we can scan 1–2 MB/ms, 128 KB bounds
-	// scan preemption at ~100 µs.
-	//
-	// This must be > _MaxSmallSize so that the object base is the
-	// span base.
-	maxObletBytes = 128 << 10
-
-	// drainCheckThreshold specifies how many units of work to do
-	// between self-preemption checks in gcDrain. Assuming a scan
-	// rate of 1 MB/ms, this is ~100 µs. Lower values have higher
-	// overhead in the scan loop (the scheduler check may perform
-	// a syscall, so its overhead is nontrivial). Higher values
-	// make the system less responsive to incoming work.
-	drainCheckThreshold = 100000
-
-	// pagesPerSpanRoot indicates how many pages to scan from a span root
-	// at a time. Used by special root marking.
-	//
-	// Higher values improve throughput by increasing locality, but
-	// increase the minimum latency of a marking operation.
-	//
-	// Must be a multiple of the pageInUse bitmap element size and
-	// must also evenly divide pagesPerArena.
-	pagesPerSpanRoot = 512
-)
-
-// gcMarkRootPrepare queues root scanning jobs (stacks, globals, and
-// some miscellany) and initializes scanning-related state.
-//
-// The world must be stopped.
-func gcMarkRootPrepare() {
-	assertWorldStopped()
-
-	// Compute how many data and BSS root blocks there are.
-	nBlocks := func(bytes uintptr) int {
-		return int(divRoundUp(bytes, rootBlockBytes))
-	}
-
-	work.nDataRoots = 0
-	work.nBSSRoots = 0
-
-	// Scan globals.
-	for _, datap := range activeModules() {
-		nDataRoots := nBlocks(datap.edata - datap.data)
-		if nDataRoots > work.nDataRoots {
-			work.nDataRoots = nDataRoots
-		}
-	}
-
-	for _, datap := range activeModules() {
-		nBSSRoots := nBlocks(datap.ebss - datap.bss)
-		if nBSSRoots > work.nBSSRoots {
-			work.nBSSRoots = nBSSRoots
-		}
-	}
-
-	// Scan span roots for finalizer specials.
-	//
-	// We depend on addfinalizer to mark objects that get
-	// finalizers after root marking.
-	//
-	// We're going to scan the whole heap (that was available at the time the
-	// mark phase started, i.e. markArenas) for in-use spans which have specials.
-	//
-	// Break up the work into arenas, and further into chunks.
-	//
-	// Snapshot allArenas as markArenas. This snapshot is safe because allArenas
-	// is append-only.
-	mheap_.markArenas = mheap_.allArenas[:len(mheap_.allArenas):len(mheap_.allArenas)]
-	work.nSpanRoots = len(mheap_.markArenas) * (pagesPerArena / pagesPerSpanRoot)
-
-	// Scan stacks.
-	//
-	// Gs may be created after this point, but it's okay that we
-	// ignore them because they begin life without any roots, so
-	// there's nothing to scan, and any roots they create during
-	// the concurrent phase will be caught by the write barrier.
-	work.stackRoots = allGsSnapshot()
-	work.nStackRoots = len(work.stackRoots)
-
-	work.markrootNext = 0
-	work.markrootJobs = uint32(fixedRootCount + work.nDataRoots + work.nBSSRoots + work.nSpanRoots + work.nStackRoots)
-
-	// Calculate base indexes of each root type
-	work.baseData = uint32(fixedRootCount)
-	work.baseBSS = work.baseData + uint32(work.nDataRoots)
-	work.baseSpans = work.baseBSS + uint32(work.nBSSRoots)
-	work.baseStacks = work.baseSpans + uint32(work.nSpanRoots)
-	work.baseEnd = work.baseStacks + uint32(work.nStackRoots)
-}
-
-// gcMarkRootCheck checks that all roots have been scanned. It is
-// purely for debugging.
-func gcMarkRootCheck() {
-	if work.markrootNext < work.markrootJobs {
-		print(work.markrootNext, " of ", work.markrootJobs, " markroot jobs done\n")
-		throw("left over markroot jobs")
-	}
-
-	// Check that stacks have been scanned.
-	//
-	// We only check the first nStackRoots Gs that we should have scanned.
-	// Since we don't care about newer Gs (see comment in
-	// gcMarkRootPrepare), no locking is required.
-	i := 0
-	forEachGRace(func(gp *g) {
-		if i >= work.nStackRoots {
-			return
-		}
-
-		if !gp.gcscandone {
-			println("gp", gp, "goid", gp.goid,
-				"status", readgstatus(gp),
-				"gcscandone", gp.gcscandone)
-			throw("scan missed a g")
-		}
-
-		i++
-	})
-}
-
-// ptrmask for an allocation containing a single pointer.
-var oneptrmask = [...]uint8{1}
-
-// markroot scans the i'th root.
-//
-// Preemption must be disabled (because this uses a gcWork).
-//
-// Returns the amount of GC work credit produced by the operation.
-// If flushBgCredit is true, then that credit is also flushed
-// to the background credit pool.
-//
-// nowritebarrier is only advisory here.
-//
-//go:nowritebarrier
-func markroot(gcw *gcWork, i uint32, flushBgCredit bool) int64 {
-	// Note: if you add a case here, please also update heapdump.go:dumproots.
-	var workDone int64
-	var workCounter *atomic.Int64
-	switch {
-	case work.baseData <= i && i < work.baseBSS:
-		workCounter = &gcController.globalsScanWork
-		for _, datap := range activeModules() {
-			workDone += markrootBlock(datap.data, datap.edata-datap.data, datap.gcdatamask.bytedata, gcw, int(i-work.baseData))
-		}
-
-	case work.baseBSS <= i && i < work.baseSpans:
-		workCounter = &gcController.globalsScanWork
-		for _, datap := range activeModules() {
-			workDone += markrootBlock(datap.bss, datap.ebss-datap.bss, datap.gcbssmask.bytedata, gcw, int(i-work.baseBSS))
-		}
-
-	case i == fixedRootFinalizers:
-		for fb := allfin; fb != nil; fb = fb.alllink {
-			cnt := uintptr(atomic.Load(&fb.cnt))
-			scanblock(uintptr(unsafe.Pointer(&fb.fin[0])), cnt*unsafe.Sizeof(fb.fin[0]), &finptrmask[0], gcw, nil)
-		}
-
-	case i == fixedRootFreeGStacks:
-		// Switch to the system stack so we can call
-		// stackfree.
-		systemstack(markrootFreeGStacks)
-
-	case work.baseSpans <= i && i < work.baseStacks:
-		// mark mspan.specials
-		markrootSpans(gcw, int(i-work.baseSpans))
-
-	default:
-		// the rest is scanning goroutine stacks
-		workCounter = &gcController.stackScanWork
-		if i < work.baseStacks || work.baseEnd <= i {
-			printlock()
-			print("runtime: markroot index ", i, " not in stack roots range [", work.baseStacks, ", ", work.baseEnd, ")\n")
-			throw("markroot: bad index")
-		}
-		gp := work.stackRoots[i-work.baseStacks]
-
-		// remember when we've first observed the G blocked
-		// needed only to output in traceback
-		status := readgstatus(gp) // We are not in a scan state
-		if (status == _Gwaiting || status == _Gsyscall) && gp.waitsince == 0 {
-			gp.waitsince = work.tstart
-		}
-
-		// scanstack must be done on the system stack in case
-		// we're trying to scan our own stack.
-		systemstack(func() {
-			// If this is a self-scan, put the user G in
-			// _Gwaiting to prevent self-deadlock. It may
-			// already be in _Gwaiting if this is a mark
-			// worker or we're in mark termination.
-			userG := getg().m.curg
-			selfScan := gp == userG && readgstatus(userG) == _Grunning
-			if selfScan {
-				casgstatus(userG, _Grunning, _Gwaiting)
-				userG.waitreason = waitReasonGarbageCollectionScan
-			}
-
-			// TODO: suspendG blocks (and spins) until gp
-			// stops, which may take a while for
-			// running goroutines. Consider doing this in
-			// two phases where the first is non-blocking:
-			// we scan the stacks we can and ask running
-			// goroutines to scan themselves; and the
-			// second blocks.
-			stopped := suspendG(gp)
-			if stopped.dead {
-				gp.gcscandone = true
-				return
-			}
-			if gp.gcscandone {
-				throw("g already scanned")
-			}
-			workDone += scanstack(gp, gcw)
-			gp.gcscandone = true
-			resumeG(stopped)
-
-			if selfScan {
-				casgstatus(userG, _Gwaiting, _Grunning)
-			}
-		})
-	}
-	if goexperiment.PacerRedesign {
-		if workCounter != nil && workDone != 0 {
-			workCounter.Add(workDone)
-			if flushBgCredit {
-				gcFlushBgCredit(workDone)
-			}
-		}
-	}
-	return workDone
-}
-
-// markrootBlock scans the shard'th shard of the block of memory [b0,
-// b0+n0), with the given pointer mask.
-//
-// Returns the amount of work done.
-//
-//go:nowritebarrier
-func markrootBlock(b0, n0 uintptr, ptrmask0 *uint8, gcw *gcWork, shard int) int64 {
-	if rootBlockBytes%(8*goarch.PtrSize) != 0 {
-		// This is necessary to pick byte offsets in ptrmask0.
-		throw("rootBlockBytes must be a multiple of 8*ptrSize")
-	}
-
-	// Note that if b0 is toward the end of the address space,
-	// then b0 + rootBlockBytes might wrap around.
-	// These tests are written to avoid any possible overflow.
-	off := uintptr(shard) * rootBlockBytes
-	if off >= n0 {
-		return 0
-	}
-	b := b0 + off
-	ptrmask := (*uint8)(add(unsafe.Pointer(ptrmask0), uintptr(shard)*(rootBlockBytes/(8*goarch.PtrSize))))
-	n := uintptr(rootBlockBytes)
-	if off+n > n0 {
-		n = n0 - off
-	}
-
-	// Scan this shard.
-	scanblock(b, n, ptrmask, gcw, nil)
-	return int64(n)
-}
-
-// markrootFreeGStacks frees stacks of dead Gs.
-//
-// This does not free stacks of dead Gs cached on Ps, but having a few
-// cached stacks around isn't a problem.
-func markrootFreeGStacks() {
-	// Take list of dead Gs with stacks.
-	lock(&sched.gFree.lock)
-	list := sched.gFree.stack
-	sched.gFree.stack = gList{}
-	unlock(&sched.gFree.lock)
-	if list.empty() {
-		return
-	}
-
-	// Free stacks.
-	q := gQueue{list.head, list.head}
-	for gp := list.head.ptr(); gp != nil; gp = gp.schedlink.ptr() {
-		stackfree(gp.stack)
-		gp.stack.lo = 0
-		gp.stack.hi = 0
-		// Manipulate the queue directly since the Gs are
-		// already all linked the right way.
-		q.tail.set(gp)
-	}
-
-	// Put Gs back on the free list.
-	lock(&sched.gFree.lock)
-	sched.gFree.noStack.pushAll(q)
-	unlock(&sched.gFree.lock)
-}
-
-// markrootSpans marks roots for one shard of markArenas.
-//
-//go:nowritebarrier
-func markrootSpans(gcw *gcWork, shard int) {
-	// Objects with finalizers have two GC-related invariants:
-	//
-	// 1) Everything reachable from the object must be marked.
-	// This ensures that when we pass the object to its finalizer,
-	// everything the finalizer can reach will be retained.
-	//
-	// 2) Finalizer specials (which are not in the garbage
-	// collected heap) are roots. In practice, this means the fn
-	// field must be scanned.
-	sg := mheap_.sweepgen
-
-	// Find the arena and page index into that arena for this shard.
-	ai := mheap_.markArenas[shard/(pagesPerArena/pagesPerSpanRoot)]
-	ha := mheap_.arenas[ai.l1()][ai.l2()]
-	arenaPage := uint(uintptr(shard) * pagesPerSpanRoot % pagesPerArena)
-
-	// Construct slice of bitmap which we'll iterate over.
-	specialsbits := ha.pageSpecials[arenaPage/8:]
-	specialsbits = specialsbits[:pagesPerSpanRoot/8]
-	for i := range specialsbits {
-		// Find set bits, which correspond to spans with specials.
-		specials := atomic.Load8(&specialsbits[i])
-		if specials == 0 {
-			continue
-		}
-		for j := uint(0); j < 8; j++ {
-			if specials&(1<<j) == 0 {
-				continue
-			}
-			// Find the span for this bit.
-			//
-			// This value is guaranteed to be non-nil because having
-			// specials implies that the span is in-use, and since we're
-			// currently marking we can be sure that we don't have to worry
-			// about the span being freed and re-used.
-			s := ha.spans[arenaPage+uint(i)*8+j]
-
-			// The state must be mSpanInUse if the specials bit is set, so
-			// sanity check that.
-			if state := s.state.get(); state != mSpanInUse {
-				print("s.state = ", state, "\n")
-				throw("non in-use span found with specials bit set")
-			}
-			// Check that this span was swept (it may be cached or uncached).
-			if !useCheckmark && !(s.sweepgen == sg || s.sweepgen == sg+3) {
-				// sweepgen was updated (+2) during non-checkmark GC pass
-				print("sweep ", s.sweepgen, " ", sg, "\n")
-				throw("gc: unswept span")
-			}
-
-			// Lock the specials to prevent a special from being
-			// removed from the list while we're traversing it.
-			lock(&s.speciallock)
-			for sp := s.specials; sp != nil; sp = sp.next {
-				if sp.kind != _KindSpecialFinalizer {
-					continue
-				}
-				// don't mark finalized object, but scan it so we
-				// retain everything it points to.
-				spf := (*specialfinalizer)(unsafe.Pointer(sp))
-				// A finalizer can be set for an inner byte of an object, find object beginning.
-				p := s.base() + uintptr(spf.special.offset)/s.elemsize*s.elemsize
-
-				// Mark everything that can be reached from
-				// the object (but *not* the object itself or
-				// we'll never collect it).
-				scanobject(p, gcw)
-
-				// The special itself is a root.
-				scanblock(uintptr(unsafe.Pointer(&spf.fn)), goarch.PtrSize, &oneptrmask[0], gcw, nil)
-			}
-			unlock(&s.speciallock)
-		}
-	}
-}
-
-// gcAssistAlloc performs GC work to make gp's assist debt positive.
-// gp must be the calling user goroutine.
-//
-// This must be called with preemption enabled.
-func gcAssistAlloc(gp *g) {
-	// Don't assist in non-preemptible contexts. These are
-	// generally fragile and won't allow the assist to block.
-	if getg() == gp.m.g0 {
-		return
-	}
-	if mp := getg().m; mp.locks > 0 || mp.preemptoff != "" {
-		return
-	}
-
-	traced := false
-retry:
-	// Compute the amount of scan work we need to do to make the
-	// balance positive. When the required amount of work is low,
-	// we over-assist to build up credit for future allocations
-	// and amortize the cost of assisting.
-	assistWorkPerByte := gcController.assistWorkPerByte.Load()
-	assistBytesPerWork := gcController.assistBytesPerWork.Load()
-	debtBytes := -gp.gcAssistBytes
-	scanWork := int64(assistWorkPerByte * float64(debtBytes))
-	if scanWork < gcOverAssistWork {
-		scanWork = gcOverAssistWork
-		debtBytes = int64(assistBytesPerWork * float64(scanWork))
-	}
-
-	// Steal as much credit as we can from the background GC's
-	// scan credit. This is racy and may drop the background
-	// credit below 0 if two mutators steal at the same time. This
-	// will just cause steals to fail until credit is accumulated
-	// again, so in the long run it doesn't really matter, but we
-	// do have to handle the negative credit case.
-	bgScanCredit := atomic.Loadint64(&gcController.bgScanCredit)
-	stolen := int64(0)
-	if bgScanCredit > 0 {
-		if bgScanCredit < scanWork {
-			stolen = bgScanCredit
-			gp.gcAssistBytes += 1 + int64(assistBytesPerWork*float64(stolen))
-		} else {
-			stolen = scanWork
-			gp.gcAssistBytes += debtBytes
-		}
-		atomic.Xaddint64(&gcController.bgScanCredit, -stolen)
-
-		scanWork -= stolen
-
-		if scanWork == 0 {
-			// We were able to steal all of the credit we
-			// needed.
-			if traced {
-				traceGCMarkAssistDone()
-			}
-			return
-		}
-	}
-
-	if trace.enabled && !traced {
-		traced = true
-		traceGCMarkAssistStart()
-	}
-
-	// Perform assist work
-	systemstack(func() {
-		gcAssistAlloc1(gp, scanWork)
-		// The user stack may have moved, so this can't touch
-		// anything on it until it returns from systemstack.
-	})
-
-	completed := gp.param != nil
-	gp.param = nil
-	if completed {
-		gcMarkDone()
-	}
-
-	if gp.gcAssistBytes < 0 {
-		// We were unable steal enough credit or perform
-		// enough work to pay off the assist debt. We need to
-		// do one of these before letting the mutator allocate
-		// more to prevent over-allocation.
-		//
-		// If this is because we were preempted, reschedule
-		// and try some more.
-		if gp.preempt {
-			Gosched()
-			goto retry
-		}
-
-		// Add this G to an assist queue and park. When the GC
-		// has more background credit, it will satisfy queued
-		// assists before flushing to the global credit pool.
-		//
-		// Note that this does *not* get woken up when more
-		// work is added to the work list. The theory is that
-		// there wasn't enough work to do anyway, so we might
-		// as well let background marking take care of the
-		// work that is available.
-		if !gcParkAssist() {
-			goto retry
-		}
-
-		// At this point either background GC has satisfied
-		// this G's assist debt, or the GC cycle is over.
-	}
-	if traced {
-		traceGCMarkAssistDone()
-	}
-}
-
-// gcAssistAlloc1 is the part of gcAssistAlloc that runs on the system
-// stack. This is a separate function to make it easier to see that
-// we're not capturing anything from the user stack, since the user
-// stack may move while we're in this function.
-//
-// gcAssistAlloc1 indicates whether this assist completed the mark
-// phase by setting gp.param to non-nil. This can't be communicated on
-// the stack since it may move.
-//
-//go:systemstack
-func gcAssistAlloc1(gp *g, scanWork int64) {
-	// Clear the flag indicating that this assist completed the
-	// mark phase.
-	gp.param = nil
-
-	if atomic.Load(&gcBlackenEnabled) == 0 {
-		// The gcBlackenEnabled check in malloc races with the
-		// store that clears it but an atomic check in every malloc
-		// would be a performance hit.
-		// Instead we recheck it here on the non-preemptable system
-		// stack to determine if we should perform an assist.
-
-		// GC is done, so ignore any remaining debt.
-		gp.gcAssistBytes = 0
-		return
-	}
-	// Track time spent in this assist. Since we're on the
-	// system stack, this is non-preemptible, so we can
-	// just measure start and end time.
-	startTime := nanotime()
-
-	decnwait := atomic.Xadd(&work.nwait, -1)
-	if decnwait == work.nproc {
-		println("runtime: work.nwait =", decnwait, "work.nproc=", work.nproc)
-		throw("nwait > work.nprocs")
-	}
-
-	// gcDrainN requires the caller to be preemptible.
-	casgstatus(gp, _Grunning, _Gwaiting)
-	gp.waitreason = waitReasonGCAssistMarking
-
-	// drain own cached work first in the hopes that it
-	// will be more cache friendly.
-	gcw := &getg().m.p.ptr().gcw
-	workDone := gcDrainN(gcw, scanWork)
-
-	casgstatus(gp, _Gwaiting, _Grunning)
-
-	// Record that we did this much scan work.
-	//
-	// Back out the number of bytes of assist credit that
-	// this scan work counts for. The "1+" is a poor man's
-	// round-up, to ensure this adds credit even if
-	// assistBytesPerWork is very low.
-	assistBytesPerWork := gcController.assistBytesPerWork.Load()
-	gp.gcAssistBytes += 1 + int64(assistBytesPerWork*float64(workDone))
-
-	// If this is the last worker and we ran out of work,
-	// signal a completion point.
-	incnwait := atomic.Xadd(&work.nwait, +1)
-	if incnwait > work.nproc {
-		println("runtime: work.nwait=", incnwait,
-			"work.nproc=", work.nproc)
-		throw("work.nwait > work.nproc")
-	}
-
-	if incnwait == work.nproc && !gcMarkWorkAvailable(nil) {
-		// This has reached a background completion point. Set
-		// gp.param to a non-nil value to indicate this. It
-		// doesn't matter what we set it to (it just has to be
-		// a valid pointer).
-		gp.param = unsafe.Pointer(gp)
-	}
-	duration := nanotime() - startTime
-	_p_ := gp.m.p.ptr()
-	_p_.gcAssistTime += duration
-	if _p_.gcAssistTime > gcAssistTimeSlack {
-		atomic.Xaddint64(&gcController.assistTime, _p_.gcAssistTime)
-		_p_.gcAssistTime = 0
-	}
-}
-
-// gcWakeAllAssists wakes all currently blocked assists. This is used
-// at the end of a GC cycle. gcBlackenEnabled must be false to prevent
-// new assists from going to sleep after this point.
-func gcWakeAllAssists() {
-	lock(&work.assistQueue.lock)
-	list := work.assistQueue.q.popList()
-	injectglist(&list)
-	unlock(&work.assistQueue.lock)
-}
-
-// gcParkAssist puts the current goroutine on the assist queue and parks.
-//
-// gcParkAssist reports whether the assist is now satisfied. If it
-// returns false, the caller must retry the assist.
-func gcParkAssist() bool {
-	lock(&work.assistQueue.lock)
-	// If the GC cycle finished while we were getting the lock,
-	// exit the assist. The cycle can't finish while we hold the
-	// lock.
-	if atomic.Load(&gcBlackenEnabled) == 0 {
-		unlock(&work.assistQueue.lock)
-		return true
-	}
-
-	gp := getg()
-	oldList := work.assistQueue.q
-	work.assistQueue.q.pushBack(gp)
-
-	// Recheck for background credit now that this G is in
-	// the queue, but can still back out. This avoids a
-	// race in case background marking has flushed more
-	// credit since we checked above.
-	if atomic.Loadint64(&gcController.bgScanCredit) > 0 {
-		work.assistQueue.q = oldList
-		if oldList.tail != 0 {
-			oldList.tail.ptr().schedlink.set(nil)
-		}
-		unlock(&work.assistQueue.lock)
-		return false
-	}
-	// Park.
-	goparkunlock(&work.assistQueue.lock, waitReasonGCAssistWait, traceEvGoBlockGC, 2)
-	return true
-}
-
-// gcFlushBgCredit flushes scanWork units of background scan work
-// credit. This first satisfies blocked assists on the
-// work.assistQueue and then flushes any remaining credit to
-// gcController.bgScanCredit.
-//
-// Write barriers are disallowed because this is used by gcDrain after
-// it has ensured that all work is drained and this must preserve that
-// condition.
-//
-//go:nowritebarrierrec
-func gcFlushBgCredit(scanWork int64) {
-	if work.assistQueue.q.empty() {
-		// Fast path; there are no blocked assists. There's a
-		// small window here where an assist may add itself to
-		// the blocked queue and park. If that happens, we'll
-		// just get it on the next flush.
-		atomic.Xaddint64(&gcController.bgScanCredit, scanWork)
-		return
-	}
-
-	assistBytesPerWork := gcController.assistBytesPerWork.Load()
-	scanBytes := int64(float64(scanWork) * assistBytesPerWork)
-
-	lock(&work.assistQueue.lock)
-	for !work.assistQueue.q.empty() && scanBytes > 0 {
-		gp := work.assistQueue.q.pop()
-		// Note that gp.gcAssistBytes is negative because gp
-		// is in debt. Think carefully about the signs below.
-		if scanBytes+gp.gcAssistBytes >= 0 {
-			// Satisfy this entire assist debt.
-			scanBytes += gp.gcAssistBytes
-			gp.gcAssistBytes = 0
-			// It's important that we *not* put gp in
-			// runnext. Otherwise, it's possible for user
-			// code to exploit the GC worker's high
-			// scheduler priority to get itself always run
-			// before other goroutines and always in the
-			// fresh quantum started by GC.
-			ready(gp, 0, false)
-		} else {
-			// Partially satisfy this assist.
-			gp.gcAssistBytes += scanBytes
-			scanBytes = 0
-			// As a heuristic, we move this assist to the
-			// back of the queue so that large assists
-			// can't clog up the assist queue and
-			// substantially delay small assists.
-			work.assistQueue.q.pushBack(gp)
-			break
-		}
-	}
-
-	if scanBytes > 0 {
-		// Convert from scan bytes back to work.
-		assistWorkPerByte := gcController.assistWorkPerByte.Load()
-		scanWork = int64(float64(scanBytes) * assistWorkPerByte)
-		atomic.Xaddint64(&gcController.bgScanCredit, scanWork)
-	}
-	unlock(&work.assistQueue.lock)
-}
-
-// scanstack scans gp's stack, greying all pointers found on the stack.
-//
-// For goexperiment.PacerRedesign:
-// Returns the amount of scan work performed, but doesn't update
-// gcController.stackScanWork or flush any credit. Any background credit produced
-// by this function should be flushed by its caller. scanstack itself can't
-// safely flush because it may result in trying to wake up a goroutine that
-// was just scanned, resulting in a self-deadlock.
-//
-// scanstack will also shrink the stack if it is safe to do so. If it
-// is not, it schedules a stack shrink for the next synchronous safe
-// point.
-//
-// scanstack is marked go:systemstack because it must not be preempted
-// while using a workbuf.
-//
-//go:nowritebarrier
-//go:systemstack
-func scanstack(gp *g, gcw *gcWork) int64 {
-	if readgstatus(gp)&_Gscan == 0 {
-		print("runtime:scanstack: gp=", gp, ", goid=", gp.goid, ", gp->atomicstatus=", hex(readgstatus(gp)), "\n")
-		throw("scanstack - bad status")
-	}
-
-	switch readgstatus(gp) &^ _Gscan {
-	default:
-		print("runtime: gp=", gp, ", goid=", gp.goid, ", gp->atomicstatus=", readgstatus(gp), "\n")
-		throw("mark - bad status")
-	case _Gdead:
-		return 0
-	case _Grunning:
-		print("runtime: gp=", gp, ", goid=", gp.goid, ", gp->atomicstatus=", readgstatus(gp), "\n")
-		throw("scanstack: goroutine not stopped")
-	case _Grunnable, _Gsyscall, _Gwaiting:
-		// ok
-	}
-
-	if gp == getg() {
-		throw("can't scan our own stack")
-	}
-
-	// stackSize is the amount of work we'll be reporting.
-	//
-	// We report the total stack size, more than we scan,
-	// because this number needs to line up with gcControllerState's
-	// stackScan and scannableStackSize fields.
-	//
-	// See the documentation on those fields for more information.
-	stackSize := gp.stack.hi - gp.stack.lo
-
-	if isShrinkStackSafe(gp) {
-		// Shrink the stack if not much of it is being used.
-		shrinkstack(gp)
-	} else {
-		// Otherwise, shrink the stack at the next sync safe point.
-		gp.preemptShrink = true
-	}
-
-	var state stackScanState
-	state.stack = gp.stack
-
-	if stackTraceDebug {
-		println("stack trace goroutine", gp.goid)
-	}
-
-	if debugScanConservative && gp.asyncSafePoint {
-		print("scanning async preempted goroutine ", gp.goid, " stack [", hex(gp.stack.lo), ",", hex(gp.stack.hi), ")\n")
-	}
-
-	// Scan the saved context register. This is effectively a live
-	// register that gets moved back and forth between the
-	// register and sched.ctxt without a write barrier.
-	if gp.sched.ctxt != nil {
-		scanblock(uintptr(unsafe.Pointer(&gp.sched.ctxt)), goarch.PtrSize, &oneptrmask[0], gcw, &state)
-	}
-
-	// Scan the stack. Accumulate a list of stack objects.
-	scanframe := func(frame *stkframe, unused unsafe.Pointer) bool {
-		scanframeworker(frame, &state, gcw)
-		return true
-	}
-	gentraceback(^uintptr(0), ^uintptr(0), 0, gp, 0, nil, 0x7fffffff, scanframe, nil, 0)
-
-	// Find additional pointers that point into the stack from the heap.
-	// Currently this includes defers and panics. See also function copystack.
-
-	// Find and trace other pointers in defer records.
-	for d := gp._defer; d != nil; d = d.link {
-		if d.fn != nil {
-			// Scan the func value, which could be a stack allocated closure.
-			// See issue 30453.
-			scanblock(uintptr(unsafe.Pointer(&d.fn)), goarch.PtrSize, &oneptrmask[0], gcw, &state)
-		}
-		if d.link != nil {
-			// The link field of a stack-allocated defer record might point
-			// to a heap-allocated defer record. Keep that heap record live.
-			scanblock(uintptr(unsafe.Pointer(&d.link)), goarch.PtrSize, &oneptrmask[0], gcw, &state)
-		}
-		// Retain defers records themselves.
-		// Defer records might not be reachable from the G through regular heap
-		// tracing because the defer linked list might weave between the stack and the heap.
-		if d.heap {
-			scanblock(uintptr(unsafe.Pointer(&d)), goarch.PtrSize, &oneptrmask[0], gcw, &state)
-		}
-	}
-	if gp._panic != nil {
-		// Panics are always stack allocated.
-		state.putPtr(uintptr(unsafe.Pointer(gp._panic)), false)
-	}
-
-	// Find and scan all reachable stack objects.
-	//
-	// The state's pointer queue prioritizes precise pointers over
-	// conservative pointers so that we'll prefer scanning stack
-	// objects precisely.
-	state.buildIndex()
-	for {
-		p, conservative := state.getPtr()
-		if p == 0 {
-			break
-		}
-		obj := state.findObject(p)
-		if obj == nil {
-			continue
-		}
-		r := obj.r
-		if r == nil {
-			// We've already scanned this object.
-			continue
-		}
-		obj.setRecord(nil) // Don't scan it again.
-		if stackTraceDebug {
-			printlock()
-			print("  live stkobj at", hex(state.stack.lo+uintptr(obj.off)), "of size", obj.size)
-			if conservative {
-				print(" (conservative)")
-			}
-			println()
-			printunlock()
-		}
-		gcdata := r.gcdata()
-		var s *mspan
-		if r.useGCProg() {
-			// This path is pretty unlikely, an object large enough
-			// to have a GC program allocated on the stack.
-			// We need some space to unpack the program into a straight
-			// bitmask, which we allocate/free here.
-			// TODO: it would be nice if there were a way to run a GC
-			// program without having to store all its bits. We'd have
-			// to change from a Lempel-Ziv style program to something else.
-			// Or we can forbid putting objects on stacks if they require
-			// a gc program (see issue 27447).
-			s = materializeGCProg(r.ptrdata(), gcdata)
-			gcdata = (*byte)(unsafe.Pointer(s.startAddr))
-		}
-
-		b := state.stack.lo + uintptr(obj.off)
-		if conservative {
-			scanConservative(b, r.ptrdata(), gcdata, gcw, &state)
-		} else {
-			scanblock(b, r.ptrdata(), gcdata, gcw, &state)
-		}
-
-		if s != nil {
-			dematerializeGCProg(s)
-		}
-	}
-
-	// Deallocate object buffers.
-	// (Pointer buffers were all deallocated in the loop above.)
-	for state.head != nil {
-		x := state.head
-		state.head = x.next
-		if stackTraceDebug {
-			for i := 0; i < x.nobj; i++ {
-				obj := &x.obj[i]
-				if obj.r == nil { // reachable
-					continue
-				}
-				println("  dead stkobj at", hex(gp.stack.lo+uintptr(obj.off)), "of size", obj.r.size)
-				// Note: not necessarily really dead - only reachable-from-ptr dead.
-			}
-		}
-		x.nobj = 0
-		putempty((*workbuf)(unsafe.Pointer(x)))
-	}
-	if state.buf != nil || state.cbuf != nil || state.freeBuf != nil {
-		throw("remaining pointer buffers")
-	}
-	return int64(stackSize)
-}
-
-// Scan a stack frame: local variables and function arguments/results.
-//go:nowritebarrier
-func scanframeworker(frame *stkframe, state *stackScanState, gcw *gcWork) {
-	if _DebugGC > 1 && frame.continpc != 0 {
-		print("scanframe ", funcname(frame.fn), "\n")
-	}
-
-	isAsyncPreempt := frame.fn.valid() && frame.fn.funcID == funcID_asyncPreempt
-	isDebugCall := frame.fn.valid() && frame.fn.funcID == funcID_debugCallV2
-	if state.conservative || isAsyncPreempt || isDebugCall {
-		if debugScanConservative {
-			println("conservatively scanning function", funcname(frame.fn), "at PC", hex(frame.continpc))
-		}
-
-		// Conservatively scan the frame. Unlike the precise
-		// case, this includes the outgoing argument space
-		// since we may have stopped while this function was
-		// setting up a call.
-		//
-		// TODO: We could narrow this down if the compiler
-		// produced a single map per function of stack slots
-		// and registers that ever contain a pointer.
-		if frame.varp != 0 {
-			size := frame.varp - frame.sp
-			if size > 0 {
-				scanConservative(frame.sp, size, nil, gcw, state)
-			}
-		}
-
-		// Scan arguments to this frame.
-		if frame.arglen != 0 {
-			// TODO: We could pass the entry argument map
-			// to narrow this down further.
-			scanConservative(frame.argp, frame.arglen, nil, gcw, state)
-		}
-
-		if isAsyncPreempt || isDebugCall {
-			// This function's frame contained the
-			// registers for the asynchronously stopped
-			// parent frame. Scan the parent
-			// conservatively.
-			state.conservative = true
-		} else {
-			// We only wanted to scan those two frames
-			// conservatively. Clear the flag for future
-			// frames.
-			state.conservative = false
-		}
-		return
-	}
-
-	locals, args, objs := getStackMap(frame, &state.cache, false)
-
-	// Scan local variables if stack frame has been allocated.
-	if locals.n > 0 {
-		size := uintptr(locals.n) * goarch.PtrSize
-		scanblock(frame.varp-size, size, locals.bytedata, gcw, state)
-	}
-
-	// Scan arguments.
-	if args.n > 0 {
-		scanblock(frame.argp, uintptr(args.n)*goarch.PtrSize, args.bytedata, gcw, state)
-	}
-
-	// Add all stack objects to the stack object list.
-	if frame.varp != 0 {
-		// varp is 0 for defers, where there are no locals.
-		// In that case, there can't be a pointer to its args, either.
-		// (And all args would be scanned above anyway.)
-		for i := range objs {
-			obj := &objs[i]
-			off := obj.off
-			base := frame.varp // locals base pointer
-			if off >= 0 {
-				base = frame.argp // arguments and return values base pointer
-			}
-			ptr := base + uintptr(off)
-			if ptr < frame.sp {
-				// object hasn't been allocated in the frame yet.
-				continue
-			}
-			if stackTraceDebug {
-				println("stkobj at", hex(ptr), "of size", obj.size)
-			}
-			state.addObject(ptr, obj)
-		}
-	}
-}
-
-type gcDrainFlags int
-
-const (
-	gcDrainUntilPreempt gcDrainFlags = 1 << iota
-	gcDrainFlushBgCredit
-	gcDrainIdle
-	gcDrainFractional
-)
-
-// gcDrain scans roots and objects in work buffers, blackening grey
-// objects until it is unable to get more work. It may return before
-// GC is done; it's the caller's responsibility to balance work from
-// other Ps.
-//
-// If flags&gcDrainUntilPreempt != 0, gcDrain returns when g.preempt
-// is set.
-//
-// If flags&gcDrainIdle != 0, gcDrain returns when there is other work
-// to do.
-//
-// If flags&gcDrainFractional != 0, gcDrain self-preempts when
-// pollFractionalWorkerExit() returns true. This implies
-// gcDrainNoBlock.
-//
-// If flags&gcDrainFlushBgCredit != 0, gcDrain flushes scan work
-// credit to gcController.bgScanCredit every gcCreditSlack units of
-// scan work.
-//
-// gcDrain will always return if there is a pending STW.
-//
-//go:nowritebarrier
-func gcDrain(gcw *gcWork, flags gcDrainFlags) {
-	if !writeBarrier.needed {
-		throw("gcDrain phase incorrect")
-	}
-
-	gp := getg().m.curg
-	preemptible := flags&gcDrainUntilPreempt != 0
-	flushBgCredit := flags&gcDrainFlushBgCredit != 0
-	idle := flags&gcDrainIdle != 0
-
-	initScanWork := gcw.heapScanWork
-
-	// checkWork is the scan work before performing the next
-	// self-preempt check.
-	checkWork := int64(1<<63 - 1)
-	var check func() bool
-	if flags&(gcDrainIdle|gcDrainFractional) != 0 {
-		checkWork = initScanWork + drainCheckThreshold
-		if idle {
-			check = pollWork
-		} else if flags&gcDrainFractional != 0 {
-			check = pollFractionalWorkerExit
-		}
-	}
-
-	// Drain root marking jobs.
-	if work.markrootNext < work.markrootJobs {
-		// Stop if we're preemptible or if someone wants to STW.
-		for !(gp.preempt && (preemptible || atomic.Load(&sched.gcwaiting) != 0)) {
-			job := atomic.Xadd(&work.markrootNext, +1) - 1
-			if job >= work.markrootJobs {
-				break
-			}
-			markroot(gcw, job, flushBgCredit)
-			if check != nil && check() {
-				goto done
-			}
-		}
-	}
-
-	// Drain heap marking jobs.
-	// Stop if we're preemptible or if someone wants to STW.
-	for !(gp.preempt && (preemptible || atomic.Load(&sched.gcwaiting) != 0)) {
-		// Try to keep work available on the global queue. We used to
-		// check if there were waiting workers, but it's better to
-		// just keep work available than to make workers wait. In the
-		// worst case, we'll do O(log(_WorkbufSize)) unnecessary
-		// balances.
-		if work.full == 0 {
-			gcw.balance()
-		}
-
-		b := gcw.tryGetFast()
-		if b == 0 {
-			b = gcw.tryGet()
-			if b == 0 {
-				// Flush the write barrier
-				// buffer; this may create
-				// more work.
-				wbBufFlush(nil, 0)
-				b = gcw.tryGet()
-			}
-		}
-		if b == 0 {
-			// Unable to get work.
-			break
-		}
-		scanobject(b, gcw)
-
-		// Flush background scan work credit to the global
-		// account if we've accumulated enough locally so
-		// mutator assists can draw on it.
-		if gcw.heapScanWork >= gcCreditSlack {
-			gcController.heapScanWork.Add(gcw.heapScanWork)
-			if flushBgCredit {
-				gcFlushBgCredit(gcw.heapScanWork - initScanWork)
-				initScanWork = 0
-			}
-			checkWork -= gcw.heapScanWork
-			gcw.heapScanWork = 0
-
-			if checkWork <= 0 {
-				checkWork += drainCheckThreshold
-				if check != nil && check() {
-					break
-				}
-			}
-		}
-	}
-
-done:
-	// Flush remaining scan work credit.
-	if gcw.heapScanWork > 0 {
-		gcController.heapScanWork.Add(gcw.heapScanWork)
-		if flushBgCredit {
-			gcFlushBgCredit(gcw.heapScanWork - initScanWork)
-		}
-		gcw.heapScanWork = 0
-	}
-}
-
-// gcDrainN blackens grey objects until it has performed roughly
-// scanWork units of scan work or the G is preempted. This is
-// best-effort, so it may perform less work if it fails to get a work
-// buffer. Otherwise, it will perform at least n units of work, but
-// may perform more because scanning is always done in whole object
-// increments. It returns the amount of scan work performed.
-//
-// The caller goroutine must be in a preemptible state (e.g.,
-// _Gwaiting) to prevent deadlocks during stack scanning. As a
-// consequence, this must be called on the system stack.
-//
-//go:nowritebarrier
-//go:systemstack
-func gcDrainN(gcw *gcWork, scanWork int64) int64 {
-	if !writeBarrier.needed {
-		throw("gcDrainN phase incorrect")
-	}
-
-	// There may already be scan work on the gcw, which we don't
-	// want to claim was done by this call.
-	workFlushed := -gcw.heapScanWork
-
-	gp := getg().m.curg
-	for !gp.preempt && workFlushed+gcw.heapScanWork < scanWork {
-		// See gcDrain comment.
-		if work.full == 0 {
-			gcw.balance()
-		}
-
-		b := gcw.tryGetFast()
-		if b == 0 {
-			b = gcw.tryGet()
-			if b == 0 {
-				// Flush the write barrier buffer;
-				// this may create more work.
-				wbBufFlush(nil, 0)
-				b = gcw.tryGet()
-			}
-		}
-
-		if b == 0 {
-			// Try to do a root job.
-			if work.markrootNext < work.markrootJobs {
-				job := atomic.Xadd(&work.markrootNext, +1) - 1
-				if job < work.markrootJobs {
-					work := markroot(gcw, job, false)
-					if goexperiment.PacerRedesign {
-						workFlushed += work
-					}
-					continue
-				}
-			}
-			// No heap or root jobs.
-			break
-		}
-
-		scanobject(b, gcw)
-
-		// Flush background scan work credit.
-		if gcw.heapScanWork >= gcCreditSlack {
-			gcController.heapScanWork.Add(gcw.heapScanWork)
-			workFlushed += gcw.heapScanWork
-			gcw.heapScanWork = 0
-		}
-	}
-
-	// Unlike gcDrain, there's no need to flush remaining work
-	// here because this never flushes to bgScanCredit and
-	// gcw.dispose will flush any remaining work to scanWork.
-
-	return workFlushed + gcw.heapScanWork
-}
-
-// scanblock scans b as scanobject would, but using an explicit
-// pointer bitmap instead of the heap bitmap.
-//
-// This is used to scan non-heap roots, so it does not update
-// gcw.bytesMarked or gcw.heapScanWork.
-//
-// If stk != nil, possible stack pointers are also reported to stk.putPtr.
-//go:nowritebarrier
-func scanblock(b0, n0 uintptr, ptrmask *uint8, gcw *gcWork, stk *stackScanState) {
-	// Use local copies of original parameters, so that a stack trace
-	// due to one of the throws below shows the original block
-	// base and extent.
-	b := b0
-	n := n0
-
-	for i := uintptr(0); i < n; {
-		// Find bits for the next word.
-		bits := uint32(*addb(ptrmask, i/(goarch.PtrSize*8)))
-		if bits == 0 {
-			i += goarch.PtrSize * 8
-			continue
-		}
-		for j := 0; j < 8 && i < n; j++ {
-			if bits&1 != 0 {
-				// Same work as in scanobject; see comments there.
-				p := *(*uintptr)(unsafe.Pointer(b + i))
-				if p != 0 {
-					if obj, span, objIndex := findObject(p, b, i); obj != 0 {
-						greyobject(obj, b, i, span, gcw, objIndex)
-					} else if stk != nil && p >= stk.stack.lo && p < stk.stack.hi {
-						stk.putPtr(p, false)
-					}
-				}
-			}
-			bits >>= 1
-			i += goarch.PtrSize
-		}
-	}
-}
-
-// scanobject scans the object starting at b, adding pointers to gcw.
-// b must point to the beginning of a heap object or an oblet.
-// scanobject consults the GC bitmap for the pointer mask and the
-// spans for the size of the object.
-//
-//go:nowritebarrier
-func scanobject(b uintptr, gcw *gcWork) {
-	// Prefetch object before we scan it.
-	//
-	// This will overlap fetching the beginning of the object with initial
-	// setup before we start scanning the object.
-	sys.Prefetch(b)
-
-	// Find the bits for b and the size of the object at b.
-	//
-	// b is either the beginning of an object, in which case this
-	// is the size of the object to scan, or it points to an
-	// oblet, in which case we compute the size to scan below.
-	hbits := heapBitsForAddr(b)
-	s := spanOfUnchecked(b)
-	n := s.elemsize
-	if n == 0 {
-		throw("scanobject n == 0")
-	}
-
-	if n > maxObletBytes {
-		// Large object. Break into oblets for better
-		// parallelism and lower latency.
-		if b == s.base() {
-			// It's possible this is a noscan object (not
-			// from greyobject, but from other code
-			// paths), in which case we must *not* enqueue
-			// oblets since their bitmaps will be
-			// uninitialized.
-			if s.spanclass.noscan() {
-				// Bypass the whole scan.
-				gcw.bytesMarked += uint64(n)
-				return
-			}
-
-			// Enqueue the other oblets to scan later.
-			// Some oblets may be in b's scalar tail, but
-			// these will be marked as "no more pointers",
-			// so we'll drop out immediately when we go to
-			// scan those.
-			for oblet := b + maxObletBytes; oblet < s.base()+s.elemsize; oblet += maxObletBytes {
-				if !gcw.putFast(oblet) {
-					gcw.put(oblet)
-				}
-			}
-		}
-
-		// Compute the size of the oblet. Since this object
-		// must be a large object, s.base() is the beginning
-		// of the object.
-		n = s.base() + s.elemsize - b
-		if n > maxObletBytes {
-			n = maxObletBytes
-		}
-	}
-
-	var i uintptr
-	for i = 0; i < n; i, hbits = i+goarch.PtrSize, hbits.next() {
-		// Load bits once. See CL 22712 and issue 16973 for discussion.
-		bits := hbits.bits()
-		if bits&bitScan == 0 {
-			break // no more pointers in this object
-		}
-		if bits&bitPointer == 0 {
-			continue // not a pointer
-		}
-
-		// Work here is duplicated in scanblock and above.
-		// If you make changes here, make changes there too.
-		obj := *(*uintptr)(unsafe.Pointer(b + i))
-
-		// At this point we have extracted the next potential pointer.
-		// Quickly filter out nil and pointers back to the current object.
-		if obj != 0 && obj-b >= n {
-			// Test if obj points into the Go heap and, if so,
-			// mark the object.
-			//
-			// Note that it's possible for findObject to
-			// fail if obj points to a just-allocated heap
-			// object because of a race with growing the
-			// heap. In this case, we know the object was
-			// just allocated and hence will be marked by
-			// allocation itself.
-			if obj, span, objIndex := findObject(obj, b, i); obj != 0 {
-				greyobject(obj, b, i, span, gcw, objIndex)
-			}
-		}
-	}
-	gcw.bytesMarked += uint64(n)
-	gcw.heapScanWork += int64(i)
-}
-
-// scanConservative scans block [b, b+n) conservatively, treating any
-// pointer-like value in the block as a pointer.
-//
-// If ptrmask != nil, only words that are marked in ptrmask are
-// considered as potential pointers.
-//
-// If state != nil, it's assumed that [b, b+n) is a block in the stack
-// and may contain pointers to stack objects.
-func scanConservative(b, n uintptr, ptrmask *uint8, gcw *gcWork, state *stackScanState) {
-	if debugScanConservative {
-		printlock()
-		print("conservatively scanning [", hex(b), ",", hex(b+n), ")\n")
-		hexdumpWords(b, b+n, func(p uintptr) byte {
-			if ptrmask != nil {
-				word := (p - b) / goarch.PtrSize
-				bits := *addb(ptrmask, word/8)
-				if (bits>>(word%8))&1 == 0 {
-					return '$'
-				}
-			}
-
-			val := *(*uintptr)(unsafe.Pointer(p))
-			if state != nil && state.stack.lo <= val && val < state.stack.hi {
-				return '@'
-			}
-
-			span := spanOfHeap(val)
-			if span == nil {
-				return ' '
-			}
-			idx := span.objIndex(val)
-			if span.isFree(idx) {
-				return ' '
-			}
-			return '*'
-		})
-		printunlock()
-	}
-
-	for i := uintptr(0); i < n; i += goarch.PtrSize {
-		if ptrmask != nil {
-			word := i / goarch.PtrSize
-			bits := *addb(ptrmask, word/8)
-			if bits == 0 {
-				// Skip 8 words (the loop increment will do the 8th)
-				//
-				// This must be the first time we've
-				// seen this word of ptrmask, so i
-				// must be 8-word-aligned, but check
-				// our reasoning just in case.
-				if i%(goarch.PtrSize*8) != 0 {
-					throw("misaligned mask")
-				}
-				i += goarch.PtrSize*8 - goarch.PtrSize
-				continue
-			}
-			if (bits>>(word%8))&1 == 0 {
-				continue
-			}
-		}
-
-		val := *(*uintptr)(unsafe.Pointer(b + i))
-
-		// Check if val points into the stack.
-		if state != nil && state.stack.lo <= val && val < state.stack.hi {
-			// val may point to a stack object. This
-			// object may be dead from last cycle and
-			// hence may contain pointers to unallocated
-			// objects, but unlike heap objects we can't
-			// tell if it's already dead. Hence, if all
-			// pointers to this object are from
-			// conservative scanning, we have to scan it
-			// defensively, too.
-			state.putPtr(val, true)
-			continue
-		}
-
-		// Check if val points to a heap span.
-		span := spanOfHeap(val)
-		if span == nil {
-			continue
-		}
-
-		// Check if val points to an allocated object.
-		idx := span.objIndex(val)
-		if span.isFree(idx) {
-			continue
-		}
-
-		// val points to an allocated object. Mark it.
-		obj := span.base() + idx*span.elemsize
-		greyobject(obj, b, i, span, gcw, idx)
-	}
-}
-
-// Shade the object if it isn't already.
-// The object is not nil and known to be in the heap.
-// Preemption must be disabled.
-//go:nowritebarrier
-func shade(b uintptr) {
-	if obj, span, objIndex := findObject(b, 0, 0); obj != 0 {
-		gcw := &getg().m.p.ptr().gcw
-		greyobject(obj, 0, 0, span, gcw, objIndex)
-	}
-}
-
-// obj is the start of an object with mark mbits.
-// If it isn't already marked, mark it and enqueue into gcw.
-// base and off are for debugging only and could be removed.
-//
-// See also wbBufFlush1, which partially duplicates this logic.
-//
-//go:nowritebarrierrec
-func greyobject(obj, base, off uintptr, span *mspan, gcw *gcWork, objIndex uintptr) {
-	// obj should be start of allocation, and so must be at least pointer-aligned.
-	if obj&(goarch.PtrSize-1) != 0 {
-		throw("greyobject: obj not pointer-aligned")
-	}
-	mbits := span.markBitsForIndex(objIndex)
-
-	if useCheckmark {
-		if setCheckmark(obj, base, off, mbits) {
-			// Already marked.
-			return
-		}
-	} else {
-		if debug.gccheckmark > 0 && span.isFree(objIndex) {
-			print("runtime: marking free object ", hex(obj), " found at *(", hex(base), "+", hex(off), ")\n")
-			gcDumpObject("base", base, off)
-			gcDumpObject("obj", obj, ^uintptr(0))
-			getg().m.traceback = 2
-			throw("marking free object")
-		}
-
-		// If marked we have nothing to do.
-		if mbits.isMarked() {
-			return
-		}
-		mbits.setMarked()
-
-		// Mark span.
-		arena, pageIdx, pageMask := pageIndexOf(span.base())
-		if arena.pageMarks[pageIdx]&pageMask == 0 {
-			atomic.Or8(&arena.pageMarks[pageIdx], pageMask)
-		}
-
-		// If this is a noscan object, fast-track it to black
-		// instead of greying it.
-		if span.spanclass.noscan() {
-			gcw.bytesMarked += uint64(span.elemsize)
-			return
-		}
-	}
-
-	// We're adding obj to P's local workbuf, so it's likely
-	// this object will be processed soon by the same P.
-	// Even if the workbuf gets flushed, there will likely still be
-	// some benefit on platforms with inclusive shared caches.
-	sys.Prefetch(obj)
-	// Queue the obj for scanning.
-	if !gcw.putFast(obj) {
-		gcw.put(obj)
-	}
-}
-
-// gcDumpObject dumps the contents of obj for debugging and marks the
-// field at byte offset off in obj.
-func gcDumpObject(label string, obj, off uintptr) {
-	s := spanOf(obj)
-	print(label, "=", hex(obj))
-	if s == nil {
-		print(" s=nil\n")
-		return
-	}
-	print(" s.base()=", hex(s.base()), " s.limit=", hex(s.limit), " s.spanclass=", s.spanclass, " s.elemsize=", s.elemsize, " s.state=")
-	if state := s.state.get(); 0 <= state && int(state) < len(mSpanStateNames) {
-		print(mSpanStateNames[state], "\n")
-	} else {
-		print("unknown(", state, ")\n")
-	}
-
-	skipped := false
-	size := s.elemsize
-	if s.state.get() == mSpanManual && size == 0 {
-		// We're printing something from a stack frame. We
-		// don't know how big it is, so just show up to an
-		// including off.
-		size = off + goarch.PtrSize
-	}
-	for i := uintptr(0); i < size; i += goarch.PtrSize {
-		// For big objects, just print the beginning (because
-		// that usually hints at the object's type) and the
-		// fields around off.
-		if !(i < 128*goarch.PtrSize || off-16*goarch.PtrSize < i && i < off+16*goarch.PtrSize) {
-			skipped = true
-			continue
-		}
-		if skipped {
-			print(" ...\n")
-			skipped = false
-		}
-		print(" *(", label, "+", i, ") = ", hex(*(*uintptr)(unsafe.Pointer(obj + i))))
-		if i == off {
-			print(" <==")
-		}
-		print("\n")
-	}
-	if skipped {
-		print(" ...\n")
-	}
-}
-
-// gcmarknewobject marks a newly allocated object black. obj must
-// not contain any non-nil pointers.
-//
-// This is nosplit so it can manipulate a gcWork without preemption.
-//
-//go:nowritebarrier
-//go:nosplit
-func gcmarknewobject(span *mspan, obj, size, scanSize uintptr) {
-	if useCheckmark { // The world should be stopped so this should not happen.
-		throw("gcmarknewobject called while doing checkmark")
-	}
-
-	// Mark object.
-	objIndex := span.objIndex(obj)
-	span.markBitsForIndex(objIndex).setMarked()
-
-	// Mark span.
-	arena, pageIdx, pageMask := pageIndexOf(span.base())
-	if arena.pageMarks[pageIdx]&pageMask == 0 {
-		atomic.Or8(&arena.pageMarks[pageIdx], pageMask)
-	}
-
-	gcw := &getg().m.p.ptr().gcw
-	gcw.bytesMarked += uint64(size)
-	if !goexperiment.PacerRedesign {
-		// The old pacer counts newly allocated memory toward
-		// heapScanWork because heapScan is continuously updated
-		// throughout the GC cycle with newly allocated memory. However,
-		// these objects are never actually scanned, so we need
-		// to account for them in heapScanWork here, "faking" their work.
-		// Otherwise the pacer will think it's always behind, potentially
-		// by a large margin.
-		//
-		// The new pacer doesn't care about this because it ceases to updated
-		// heapScan once a GC cycle starts, effectively snapshotting it.
-		gcw.heapScanWork += int64(scanSize)
-	}
-}
-
-// gcMarkTinyAllocs greys all active tiny alloc blocks.
-//
-// The world must be stopped.
-func gcMarkTinyAllocs() {
-	assertWorldStopped()
-
-	for _, p := range allp {
-		c := p.mcache
-		if c == nil || c.tiny == 0 {
-			continue
-		}
-		_, span, objIndex := findObject(c.tiny, 0, 0)
-		gcw := &p.gcw
-		greyobject(c.tiny, 0, 0, span, gcw, objIndex)
-	}
-}
diff --git a/contrib/go/_std_1.18/src/runtime/mgcpacer.go b/contrib/go/_std_1.18/src/runtime/mgcpacer.go
deleted file mode 100644
index d54dbc26c2..0000000000
--- a/contrib/go/_std_1.18/src/runtime/mgcpacer.go
+++ /dev/null
@@ -1,1348 +0,0 @@
-// Copyright 2021 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"internal/cpu"
-	"internal/goexperiment"
-	"runtime/internal/atomic"
-	"unsafe"
-)
-
-const (
-	// gcGoalUtilization is the goal CPU utilization for
-	// marking as a fraction of GOMAXPROCS.
-	gcGoalUtilization = goexperiment.PacerRedesignInt*gcBackgroundUtilization +
-		(1-goexperiment.PacerRedesignInt)*(gcBackgroundUtilization+0.05)
-
-	// gcBackgroundUtilization is the fixed CPU utilization for background
-	// marking. It must be <= gcGoalUtilization. The difference between
-	// gcGoalUtilization and gcBackgroundUtilization will be made up by
-	// mark assists. The scheduler will aim to use within 50% of this
-	// goal.
-	//
-	// Setting this to < gcGoalUtilization avoids saturating the trigger
-	// feedback controller when there are no assists, which allows it to
-	// better control CPU and heap growth. However, the larger the gap,
-	// the more mutator assists are expected to happen, which impact
-	// mutator latency.
-	//
-	// If goexperiment.PacerRedesign, the trigger feedback controller
-	// is replaced with an estimate of the mark/cons ratio that doesn't
-	// have the same saturation issues, so this is set equal to
-	// gcGoalUtilization.
-	gcBackgroundUtilization = 0.25
-
-	// gcCreditSlack is the amount of scan work credit that can
-	// accumulate locally before updating gcController.heapScanWork and,
-	// optionally, gcController.bgScanCredit. Lower values give a more
-	// accurate assist ratio and make it more likely that assists will
-	// successfully steal background credit. Higher values reduce memory
-	// contention.
-	gcCreditSlack = 2000
-
-	// gcAssistTimeSlack is the nanoseconds of mutator assist time that
-	// can accumulate on a P before updating gcController.assistTime.
-	gcAssistTimeSlack = 5000
-
-	// gcOverAssistWork determines how many extra units of scan work a GC
-	// assist does when an assist happens. This amortizes the cost of an
-	// assist by pre-paying for this many bytes of future allocations.
-	gcOverAssistWork = 64 << 10
-
-	// defaultHeapMinimum is the value of heapMinimum for GOGC==100.
-	defaultHeapMinimum = (goexperiment.HeapMinimum512KiBInt)*(512<<10) +
-		(1-goexperiment.HeapMinimum512KiBInt)*(4<<20)
-
-	// scannableStackSizeSlack is the bytes of stack space allocated or freed
-	// that can accumulate on a P before updating gcController.stackSize.
-	scannableStackSizeSlack = 8 << 10
-)
-
-func init() {
-	if offset := unsafe.Offsetof(gcController.heapLive); offset%8 != 0 {
-		println(offset)
-		throw("gcController.heapLive not aligned to 8 bytes")
-	}
-}
-
-// gcController implements the GC pacing controller that determines
-// when to trigger concurrent garbage collection and how much marking
-// work to do in mutator assists and background marking.
-//
-// It uses a feedback control algorithm to adjust the gcController.trigger
-// trigger based on the heap growth and GC CPU utilization each cycle.
-// This algorithm optimizes for heap growth to match GOGC and for CPU
-// utilization between assist and background marking to be 25% of
-// GOMAXPROCS. The high-level design of this algorithm is documented
-// at https://golang.org/s/go15gcpacing.
-//
-// All fields of gcController are used only during a single mark
-// cycle.
-var gcController gcControllerState
-
-type gcControllerState struct {
-
-	// Initialized from GOGC. GOGC=off means no GC.
-	gcPercent atomic.Int32
-
-	_ uint32 // padding so following 64-bit values are 8-byte aligned
-
-	// heapMinimum is the minimum heap size at which to trigger GC.
-	// For small heaps, this overrides the usual GOGC*live set rule.
-	//
-	// When there is a very small live set but a lot of allocation, simply
-	// collecting when the heap reaches GOGC*live results in many GC
-	// cycles and high total per-GC overhead. This minimum amortizes this
-	// per-GC overhead while keeping the heap reasonably small.
-	//
-	// During initialization this is set to 4MB*GOGC/100. In the case of
-	// GOGC==0, this will set heapMinimum to 0, resulting in constant
-	// collection even when the heap size is small, which is useful for
-	// debugging.
-	heapMinimum uint64
-
-	// triggerRatio is the heap growth ratio that triggers marking.
-	//
-	// E.g., if this is 0.6, then GC should start when the live
-	// heap has reached 1.6 times the heap size marked by the
-	// previous cycle. This should be ≤ GOGC/100 so the trigger
-	// heap size is less than the goal heap size. This is set
-	// during mark termination for the next cycle's trigger.
-	//
-	// Protected by mheap_.lock or a STW.
-	//
-	// Used if !goexperiment.PacerRedesign.
-	triggerRatio float64
-
-	// trigger is the heap size that triggers marking.
-	//
-	// When heapLive ≥ trigger, the mark phase will start.
-	// This is also the heap size by which proportional sweeping
-	// must be complete.
-	//
-	// This is computed from triggerRatio during mark termination
-	// for the next cycle's trigger.
-	//
-	// Protected by mheap_.lock or a STW.
-	trigger uint64
-
-	// consMark is the estimated per-CPU consMark ratio for the application.
-	//
-	// It represents the ratio between the application's allocation
-	// rate, as bytes allocated per CPU-time, and the GC's scan rate,
-	// as bytes scanned per CPU-time.
-	// The units of this ratio are (B / cpu-ns) / (B / cpu-ns).
-	//
-	// At a high level, this value is computed as the bytes of memory
-	// allocated (cons) per unit of scan work completed (mark) in a GC
-	// cycle, divided by the CPU time spent on each activity.
-	//
-	// Updated at the end of each GC cycle, in endCycle.
-	//
-	// For goexperiment.PacerRedesign.
-	consMark float64
-
-	// consMarkController holds the state for the mark-cons ratio
-	// estimation over time.
-	//
-	// Its purpose is to smooth out noisiness in the computation of
-	// consMark; see consMark for details.
-	//
-	// For goexperiment.PacerRedesign.
-	consMarkController piController
-
-	_ uint32 // Padding for atomics on 32-bit platforms.
-
-	// heapGoal is the goal heapLive for when next GC ends.
-	// Set to ^uint64(0) if disabled.
-	//
-	// Read and written atomically, unless the world is stopped.
-	heapGoal uint64
-
-	// lastHeapGoal is the value of heapGoal for the previous GC.
-	// Note that this is distinct from the last value heapGoal had,
-	// because it could change if e.g. gcPercent changes.
-	//
-	// Read and written with the world stopped or with mheap_.lock held.
-	lastHeapGoal uint64
-
-	// heapLive is the number of bytes considered live by the GC.
-	// That is: retained by the most recent GC plus allocated
-	// since then. heapLive ≤ memstats.heapAlloc, since heapAlloc includes
-	// unmarked objects that have not yet been swept (and hence goes up as we
-	// allocate and down as we sweep) while heapLive excludes these
-	// objects (and hence only goes up between GCs).
-	//
-	// This is updated atomically without locking. To reduce
-	// contention, this is updated only when obtaining a span from
-	// an mcentral and at this point it counts all of the
-	// unallocated slots in that span (which will be allocated
-	// before that mcache obtains another span from that
-	// mcentral). Hence, it slightly overestimates the "true" live
-	// heap size. It's better to overestimate than to
-	// underestimate because 1) this triggers the GC earlier than
-	// necessary rather than potentially too late and 2) this
-	// leads to a conservative GC rate rather than a GC rate that
-	// is potentially too low.
-	//
-	// Reads should likewise be atomic (or during STW).
-	//
-	// Whenever this is updated, call traceHeapAlloc() and
-	// this gcControllerState's revise() method.
-	heapLive uint64
-
-	// heapScan is the number of bytes of "scannable" heap. This
-	// is the live heap (as counted by heapLive), but omitting
-	// no-scan objects and no-scan tails of objects.
-	//
-	// For !goexperiment.PacerRedesign: Whenever this is updated,
-	// call this gcControllerState's revise() method. It is read
-	// and written atomically or with the world stopped.
-	//
-	// For goexperiment.PacerRedesign: This value is fixed at the
-	// start of a GC cycle, so during a GC cycle it is safe to
-	// read without atomics, and it represents the maximum scannable
-	// heap.
-	heapScan uint64
-
-	// lastHeapScan is the number of bytes of heap that were scanned
-	// last GC cycle. It is the same as heapMarked, but only
-	// includes the "scannable" parts of objects.
-	//
-	// Updated when the world is stopped.
-	lastHeapScan uint64
-
-	// stackScan is a snapshot of scannableStackSize taken at each GC
-	// STW pause and is used in pacing decisions.
-	//
-	// Updated only while the world is stopped.
-	stackScan uint64
-
-	// scannableStackSize is the amount of allocated goroutine stack space in
-	// use by goroutines.
-	//
-	// This number tracks allocated goroutine stack space rather than used
-	// goroutine stack space (i.e. what is actually scanned) because used
-	// goroutine stack space is much harder to measure cheaply. By using
-	// allocated space, we make an overestimate; this is OK, it's better
-	// to conservatively overcount than undercount.
-	//
-	// Read and updated atomically.
-	scannableStackSize uint64
-
-	// globalsScan is the total amount of global variable space
-	// that is scannable.
-	//
-	// Read and updated atomically.
-	globalsScan uint64
-
-	// heapMarked is the number of bytes marked by the previous
-	// GC. After mark termination, heapLive == heapMarked, but
-	// unlike heapLive, heapMarked does not change until the
-	// next mark termination.
-	heapMarked uint64
-
-	// heapScanWork is the total heap scan work performed this cycle.
-	// stackScanWork is the total stack scan work performed this cycle.
-	// globalsScanWork is the total globals scan work performed this cycle.
-	//
-	// These are updated atomically during the cycle. Updates occur in
-	// bounded batches, since they are both written and read
-	// throughout the cycle. At the end of the cycle, heapScanWork is how
-	// much of the retained heap is scannable.
-	//
-	// Currently these are measured in bytes. For most uses, this is an
-	// opaque unit of work, but for estimation the definition is important.
-	//
-	// Note that stackScanWork includes all allocated space, not just the
-	// size of the stack itself, mirroring stackSize.
-	//
-	// For !goexperiment.PacerRedesign, stackScanWork and globalsScanWork
-	// are always zero.
-	heapScanWork    atomic.Int64
-	stackScanWork   atomic.Int64
-	globalsScanWork atomic.Int64
-
-	// bgScanCredit is the scan work credit accumulated by the
-	// concurrent background scan. This credit is accumulated by
-	// the background scan and stolen by mutator assists. This is
-	// updated atomically. Updates occur in bounded batches, since
-	// it is both written and read throughout the cycle.
-	bgScanCredit int64
-
-	// assistTime is the nanoseconds spent in mutator assists
-	// during this cycle. This is updated atomically. Updates
-	// occur in bounded batches, since it is both written and read
-	// throughout the cycle.
-	assistTime int64
-
-	// dedicatedMarkTime is the nanoseconds spent in dedicated
-	// mark workers during this cycle. This is updated atomically
-	// at the end of the concurrent mark phase.
-	dedicatedMarkTime int64
-
-	// fractionalMarkTime is the nanoseconds spent in the
-	// fractional mark worker during this cycle. This is updated
-	// atomically throughout the cycle and will be up-to-date if
-	// the fractional mark worker is not currently running.
-	fractionalMarkTime int64
-
-	// idleMarkTime is the nanoseconds spent in idle marking
-	// during this cycle. This is updated atomically throughout
-	// the cycle.
-	idleMarkTime int64
-
-	// markStartTime is the absolute start time in nanoseconds
-	// that assists and background mark workers started.
-	markStartTime int64
-
-	// dedicatedMarkWorkersNeeded is the number of dedicated mark
-	// workers that need to be started. This is computed at the
-	// beginning of each cycle and decremented atomically as
-	// dedicated mark workers get started.
-	dedicatedMarkWorkersNeeded int64
-
-	// assistWorkPerByte is the ratio of scan work to allocated
-	// bytes that should be performed by mutator assists. This is
-	// computed at the beginning of each cycle and updated every
-	// time heapScan is updated.
-	assistWorkPerByte atomic.Float64
-
-	// assistBytesPerWork is 1/assistWorkPerByte.
-	//
-	// Note that because this is read and written independently
-	// from assistWorkPerByte users may notice a skew between
-	// the two values, and such a state should be safe.
-	assistBytesPerWork atomic.Float64
-
-	// fractionalUtilizationGoal is the fraction of wall clock
-	// time that should be spent in the fractional mark worker on
-	// each P that isn't running a dedicated worker.
-	//
-	// For example, if the utilization goal is 25% and there are
-	// no dedicated workers, this will be 0.25. If the goal is
-	// 25%, there is one dedicated worker, and GOMAXPROCS is 5,
-	// this will be 0.05 to make up the missing 5%.
-	//
-	// If this is zero, no fractional workers are needed.
-	fractionalUtilizationGoal float64
-
-	// test indicates that this is a test-only copy of gcControllerState.
-	test bool
-
-	_ cpu.CacheLinePad
-}
-
-func (c *gcControllerState) init(gcPercent int32) {
-	c.heapMinimum = defaultHeapMinimum
-
-	if goexperiment.PacerRedesign {
-		c.consMarkController = piController{
-			// Tuned first via the Ziegler-Nichols process in simulation,
-			// then the integral time was manually tuned against real-world
-			// applications to deal with noisiness in the measured cons/mark
-			// ratio.
-			kp: 0.9,
-			ti: 4.0,
-
-			// Set a high reset time in GC cycles.
-			// This is inversely proportional to the rate at which we
-			// accumulate error from clipping. By making this very high
-			// we make the accumulation slow. In general, clipping is
-			// OK in our situation, hence the choice.
-			//
-			// Tune this if we get unintended effects from clipping for
-			// a long time.
-			tt:  1000,
-			min: -1000,
-			max: 1000,
-		}
-	} else {
-		// Set a reasonable initial GC trigger.
-		c.triggerRatio = 7 / 8.0
-
-		// Fake a heapMarked value so it looks like a trigger at
-		// heapMinimum is the appropriate growth from heapMarked.
-		// This will go into computing the initial GC goal.
-		c.heapMarked = uint64(float64(c.heapMinimum) / (1 + c.triggerRatio))
-	}
-
-	// This will also compute and set the GC trigger and goal.
-	c.setGCPercent(gcPercent)
-}
-
-// startCycle resets the GC controller's state and computes estimates
-// for a new GC cycle. The caller must hold worldsema and the world
-// must be stopped.
-func (c *gcControllerState) startCycle(markStartTime int64, procs int) {
-	c.heapScanWork.Store(0)
-	c.stackScanWork.Store(0)
-	c.globalsScanWork.Store(0)
-	c.bgScanCredit = 0
-	c.assistTime = 0
-	c.dedicatedMarkTime = 0
-	c.fractionalMarkTime = 0
-	c.idleMarkTime = 0
-	c.markStartTime = markStartTime
-	c.stackScan = atomic.Load64(&c.scannableStackSize)
-
-	// Ensure that the heap goal is at least a little larger than
-	// the current live heap size. This may not be the case if GC
-	// start is delayed or if the allocation that pushed gcController.heapLive
-	// over trigger is large or if the trigger is really close to
-	// GOGC. Assist is proportional to this distance, so enforce a
-	// minimum distance, even if it means going over the GOGC goal
-	// by a tiny bit.
-	if goexperiment.PacerRedesign {
-		if c.heapGoal < c.heapLive+64<<10 {
-			c.heapGoal = c.heapLive + 64<<10
-		}
-	} else {
-		if c.heapGoal < c.heapLive+1<<20 {
-			c.heapGoal = c.heapLive + 1<<20
-		}
-	}
-
-	// Compute the background mark utilization goal. In general,
-	// this may not come out exactly. We round the number of
-	// dedicated workers so that the utilization is closest to
-	// 25%. For small GOMAXPROCS, this would introduce too much
-	// error, so we add fractional workers in that case.
-	totalUtilizationGoal := float64(procs) * gcBackgroundUtilization
-	c.dedicatedMarkWorkersNeeded = int64(totalUtilizationGoal + 0.5)
-	utilError := float64(c.dedicatedMarkWorkersNeeded)/totalUtilizationGoal - 1
-	const maxUtilError = 0.3
-	if utilError < -maxUtilError || utilError > maxUtilError {
-		// Rounding put us more than 30% off our goal. With
-		// gcBackgroundUtilization of 25%, this happens for
-		// GOMAXPROCS<=3 or GOMAXPROCS=6. Enable fractional
-		// workers to compensate.
-		if float64(c.dedicatedMarkWorkersNeeded) > totalUtilizationGoal {
-			// Too many dedicated workers.
-			c.dedicatedMarkWorkersNeeded--
-		}
-		c.fractionalUtilizationGoal = (totalUtilizationGoal - float64(c.dedicatedMarkWorkersNeeded)) / float64(procs)
-	} else {
-		c.fractionalUtilizationGoal = 0
-	}
-
-	// In STW mode, we just want dedicated workers.
-	if debug.gcstoptheworld > 0 {
-		c.dedicatedMarkWorkersNeeded = int64(procs)
-		c.fractionalUtilizationGoal = 0
-	}
-
-	// Clear per-P state
-	for _, p := range allp {
-		p.gcAssistTime = 0
-		p.gcFractionalMarkTime = 0
-	}
-
-	// Compute initial values for controls that are updated
-	// throughout the cycle.
-	c.revise()
-
-	if debug.gcpacertrace > 0 {
-		assistRatio := c.assistWorkPerByte.Load()
-		print("pacer: assist ratio=", assistRatio,
-			" (scan ", gcController.heapScan>>20, " MB in ",
-			work.initialHeapLive>>20, "->",
-			c.heapGoal>>20, " MB)",
-			" workers=", c.dedicatedMarkWorkersNeeded,
-			"+", c.fractionalUtilizationGoal, "\n")
-	}
-}
-
-// revise updates the assist ratio during the GC cycle to account for
-// improved estimates. This should be called whenever gcController.heapScan,
-// gcController.heapLive, or gcController.heapGoal is updated. It is safe to
-// call concurrently, but it may race with other calls to revise.
-//
-// The result of this race is that the two assist ratio values may not line
-// up or may be stale. In practice this is OK because the assist ratio
-// moves slowly throughout a GC cycle, and the assist ratio is a best-effort
-// heuristic anyway. Furthermore, no part of the heuristic depends on
-// the two assist ratio values being exact reciprocals of one another, since
-// the two values are used to convert values from different sources.
-//
-// The worst case result of this raciness is that we may miss a larger shift
-// in the ratio (say, if we decide to pace more aggressively against the
-// hard heap goal) but even this "hard goal" is best-effort (see #40460).
-// The dedicated GC should ensure we don't exceed the hard goal by too much
-// in the rare case we do exceed it.
-//
-// It should only be called when gcBlackenEnabled != 0 (because this
-// is when assists are enabled and the necessary statistics are
-// available).
-func (c *gcControllerState) revise() {
-	gcPercent := c.gcPercent.Load()
-	if gcPercent < 0 {
-		// If GC is disabled but we're running a forced GC,
-		// act like GOGC is huge for the below calculations.
-		gcPercent = 100000
-	}
-	live := atomic.Load64(&c.heapLive)
-	scan := atomic.Load64(&c.heapScan)
-	work := c.heapScanWork.Load() + c.stackScanWork.Load() + c.globalsScanWork.Load()
-
-	// Assume we're under the soft goal. Pace GC to complete at
-	// heapGoal assuming the heap is in steady-state.
-	heapGoal := int64(atomic.Load64(&c.heapGoal))
-
-	var scanWorkExpected int64
-	if goexperiment.PacerRedesign {
-		// The expected scan work is computed as the amount of bytes scanned last
-		// GC cycle, plus our estimate of stacks and globals work for this cycle.
-		scanWorkExpected = int64(c.lastHeapScan + c.stackScan + c.globalsScan)
-
-		// maxScanWork is a worst-case estimate of the amount of scan work that
-		// needs to be performed in this GC cycle. Specifically, it represents
-		// the case where *all* scannable memory turns out to be live.
-		maxScanWork := int64(scan + c.stackScan + c.globalsScan)
-		if work > scanWorkExpected {
-			// We've already done more scan work than expected. Because our expectation
-			// is based on a steady-state scannable heap size, we assume this means our
-			// heap is growing. Compute a new heap goal that takes our existing runway
-			// computed for scanWorkExpected and extrapolates it to maxScanWork, the worst-case
-			// scan work. This keeps our assist ratio stable if the heap continues to grow.
-			//
-			// The effect of this mechanism is that assists stay flat in the face of heap
-			// growths. It's OK to use more memory this cycle to scan all the live heap,
-			// because the next GC cycle is inevitably going to use *at least* that much
-			// memory anyway.
-			extHeapGoal := int64(float64(heapGoal-int64(c.trigger))/float64(scanWorkExpected)*float64(maxScanWork)) + int64(c.trigger)
-			scanWorkExpected = maxScanWork
-
-			// hardGoal is a hard limit on the amount that we're willing to push back the
-			// heap goal, and that's twice the heap goal (i.e. if GOGC=100 and the heap and/or
-			// stacks and/or globals grow to twice their size, this limits the current GC cycle's
-			// growth to 4x the original live heap's size).
-			//
-			// This maintains the invariant that we use no more memory than the next GC cycle
-			// will anyway.
-			hardGoal := int64((1.0 + float64(gcPercent)/100.0) * float64(heapGoal))
-			if extHeapGoal > hardGoal {
-				extHeapGoal = hardGoal
-			}
-			heapGoal = extHeapGoal
-		}
-		if int64(live) > heapGoal {
-			// We're already past our heap goal, even the extrapolated one.
-			// Leave ourselves some extra runway, so in the worst case we
-			// finish by that point.
-			const maxOvershoot = 1.1
-			heapGoal = int64(float64(heapGoal) * maxOvershoot)
-
-			// Compute the upper bound on the scan work remaining.
-			scanWorkExpected = maxScanWork
-		}
-	} else {
-		// Compute the expected scan work remaining.
-		//
-		// This is estimated based on the expected
-		// steady-state scannable heap. For example, with
-		// GOGC=100, only half of the scannable heap is
-		// expected to be live, so that's what we target.
-		//
-		// (This is a float calculation to avoid overflowing on
-		// 100*heapScan.)
-		scanWorkExpected = int64(float64(scan) * 100 / float64(100+gcPercent))
-		if int64(live) > heapGoal || work > scanWorkExpected {
-			// We're past the soft goal, or we've already done more scan
-			// work than we expected. Pace GC so that in the worst case it
-			// will complete by the hard goal.
-			const maxOvershoot = 1.1
-			heapGoal = int64(float64(heapGoal) * maxOvershoot)
-
-			// Compute the upper bound on the scan work remaining.
-			scanWorkExpected = int64(scan)
-		}
-	}
-
-	// Compute the remaining scan work estimate.
-	//
-	// Note that we currently count allocations during GC as both
-	// scannable heap (heapScan) and scan work completed
-	// (scanWork), so allocation will change this difference
-	// slowly in the soft regime and not at all in the hard
-	// regime.
-	scanWorkRemaining := scanWorkExpected - work
-	if scanWorkRemaining < 1000 {
-		// We set a somewhat arbitrary lower bound on
-		// remaining scan work since if we aim a little high,
-		// we can miss by a little.
-		//
-		// We *do* need to enforce that this is at least 1,
-		// since marking is racy and double-scanning objects
-		// may legitimately make the remaining scan work
-		// negative, even in the hard goal regime.
-		scanWorkRemaining = 1000
-	}
-
-	// Compute the heap distance remaining.
-	heapRemaining := heapGoal - int64(live)
-	if heapRemaining <= 0 {
-		// This shouldn't happen, but if it does, avoid
-		// dividing by zero or setting the assist negative.
-		heapRemaining = 1
-	}
-
-	// Compute the mutator assist ratio so by the time the mutator
-	// allocates the remaining heap bytes up to heapGoal, it will
-	// have done (or stolen) the remaining amount of scan work.
-	// Note that the assist ratio values are updated atomically
-	// but not together. This means there may be some degree of
-	// skew between the two values. This is generally OK as the
-	// values shift relatively slowly over the course of a GC
-	// cycle.
-	assistWorkPerByte := float64(scanWorkRemaining) / float64(heapRemaining)
-	assistBytesPerWork := float64(heapRemaining) / float64(scanWorkRemaining)
-	c.assistWorkPerByte.Store(assistWorkPerByte)
-	c.assistBytesPerWork.Store(assistBytesPerWork)
-}
-
-// endCycle computes the trigger ratio (!goexperiment.PacerRedesign)
-// or the consMark estimate (goexperiment.PacerRedesign) for the next cycle.
-// Returns the trigger ratio if application, or 0 (goexperiment.PacerRedesign).
-// userForced indicates whether the current GC cycle was forced
-// by the application.
-func (c *gcControllerState) endCycle(now int64, procs int, userForced bool) float64 {
-	// Record last heap goal for the scavenger.
-	// We'll be updating the heap goal soon.
-	gcController.lastHeapGoal = gcController.heapGoal
-
-	// Compute the duration of time for which assists were turned on.
-	assistDuration := now - c.markStartTime
-
-	// Assume background mark hit its utilization goal.
-	utilization := gcBackgroundUtilization
-	// Add assist utilization; avoid divide by zero.
-	if assistDuration > 0 {
-		utilization += float64(c.assistTime) / float64(assistDuration*int64(procs))
-	}
-
-	if goexperiment.PacerRedesign {
-		if c.heapLive <= c.trigger {
-			// Shouldn't happen, but let's be very safe about this in case the
-			// GC is somehow extremely short.
-			//
-			// In this case though, the only reasonable value for c.heapLive-c.trigger
-			// would be 0, which isn't really all that useful, i.e. the GC was so short
-			// that it didn't matter.
-			//
-			// Ignore this case and don't update anything.
-			return 0
-		}
-		idleUtilization := 0.0
-		if assistDuration > 0 {
-			idleUtilization = float64(c.idleMarkTime) / float64(assistDuration*int64(procs))
-		}
-		// Determine the cons/mark ratio.
-		//
-		// The units we want for the numerator and denominator are both B / cpu-ns.
-		// We get this by taking the bytes allocated or scanned, and divide by the amount of
-		// CPU time it took for those operations. For allocations, that CPU time is
-		//
-		//    assistDuration * procs * (1 - utilization)
-		//
-		// Where utilization includes just background GC workers and assists. It does *not*
-		// include idle GC work time, because in theory the mutator is free to take that at
-		// any point.
-		//
-		// For scanning, that CPU time is
-		//
-		//    assistDuration * procs * (utilization + idleUtilization)
-		//
-		// In this case, we *include* idle utilization, because that is additional CPU time that the
-		// the GC had available to it.
-		//
-		// In effect, idle GC time is sort of double-counted here, but it's very weird compared
-		// to other kinds of GC work, because of how fluid it is. Namely, because the mutator is
-		// *always* free to take it.
-		//
-		// So this calculation is really:
-		//     (heapLive-trigger) / (assistDuration * procs * (1-utilization)) /
-		//         (scanWork) / (assistDuration * procs * (utilization+idleUtilization)
-		//
-		// Note that because we only care about the ratio, assistDuration and procs cancel out.
-		scanWork := c.heapScanWork.Load() + c.stackScanWork.Load() + c.globalsScanWork.Load()
-		currentConsMark := (float64(c.heapLive-c.trigger) * (utilization + idleUtilization)) /
-			(float64(scanWork) * (1 - utilization))
-
-		// Update cons/mark controller. The time period for this is 1 GC cycle.
-		//
-		// This use of a PI controller might seem strange. So, here's an explanation:
-		//
-		// currentConsMark represents the consMark we *should've* had to be perfectly
-		// on-target for this cycle. Given that we assume the next GC will be like this
-		// one in the steady-state, it stands to reason that we should just pick that
-		// as our next consMark. In practice, however, currentConsMark is too noisy:
-		// we're going to be wildly off-target in each GC cycle if we do that.
-		//
-		// What we do instead is make a long-term assumption: there is some steady-state
-		// consMark value, but it's obscured by noise. By constantly shooting for this
-		// noisy-but-perfect consMark value, the controller will bounce around a bit,
-		// but its average behavior, in aggregate, should be less noisy and closer to
-		// the true long-term consMark value, provided its tuned to be slightly overdamped.
-		var ok bool
-		oldConsMark := c.consMark
-		c.consMark, ok = c.consMarkController.next(c.consMark, currentConsMark, 1.0)
-		if !ok {
-			// The error spiraled out of control. This is incredibly unlikely seeing
-			// as this controller is essentially just a smoothing function, but it might
-			// mean that something went very wrong with how currentConsMark was calculated.
-			// Just reset consMark and keep going.
-			c.consMark = 0
-		}
-
-		if debug.gcpacertrace > 0 {
-			printlock()
-			goal := gcGoalUtilization * 100
-			print("pacer: ", int(utilization*100), "% CPU (", int(goal), " exp.) for ")
-			print(c.heapScanWork.Load(), "+", c.stackScanWork.Load(), "+", c.globalsScanWork.Load(), " B work (", c.lastHeapScan+c.stackScan+c.globalsScan, " B exp.) ")
-			print("in ", c.trigger, " B -> ", c.heapLive, " B (∆goal ", int64(c.heapLive)-int64(c.heapGoal), ", cons/mark ", oldConsMark, ")")
-			if !ok {
-				print("[controller reset]")
-			}
-			println()
-			printunlock()
-		}
-		return 0
-	}
-
-	// !goexperiment.PacerRedesign below.
-
-	if userForced {
-		// Forced GC means this cycle didn't start at the
-		// trigger, so where it finished isn't good
-		// information about how to adjust the trigger.
-		// Just leave it where it is.
-		return c.triggerRatio
-	}
-
-	// Proportional response gain for the trigger controller. Must
-	// be in [0, 1]. Lower values smooth out transient effects but
-	// take longer to respond to phase changes. Higher values
-	// react to phase changes quickly, but are more affected by
-	// transient changes. Values near 1 may be unstable.
-	const triggerGain = 0.5
-
-	// Compute next cycle trigger ratio. First, this computes the
-	// "error" for this cycle; that is, how far off the trigger
-	// was from what it should have been, accounting for both heap
-	// growth and GC CPU utilization. We compute the actual heap
-	// growth during this cycle and scale that by how far off from
-	// the goal CPU utilization we were (to estimate the heap
-	// growth if we had the desired CPU utilization). The
-	// difference between this estimate and the GOGC-based goal
-	// heap growth is the error.
-	goalGrowthRatio := c.effectiveGrowthRatio()
-	actualGrowthRatio := float64(c.heapLive)/float64(c.heapMarked) - 1
-	triggerError := goalGrowthRatio - c.triggerRatio - utilization/gcGoalUtilization*(actualGrowthRatio-c.triggerRatio)
-
-	// Finally, we adjust the trigger for next time by this error,
-	// damped by the proportional gain.
-	triggerRatio := c.triggerRatio + triggerGain*triggerError
-
-	if debug.gcpacertrace > 0 {
-		// Print controller state in terms of the design
-		// document.
-		H_m_prev := c.heapMarked
-		h_t := c.triggerRatio
-		H_T := c.trigger
-		h_a := actualGrowthRatio
-		H_a := c.heapLive
-		h_g := goalGrowthRatio
-		H_g := int64(float64(H_m_prev) * (1 + h_g))
-		u_a := utilization
-		u_g := gcGoalUtilization
-		W_a := c.heapScanWork.Load()
-		print("pacer: H_m_prev=", H_m_prev,
-			" h_t=", h_t, " H_T=", H_T,
-			" h_a=", h_a, " H_a=", H_a,
-			" h_g=", h_g, " H_g=", H_g,
-			" u_a=", u_a, " u_g=", u_g,
-			" W_a=", W_a,
-			" goalΔ=", goalGrowthRatio-h_t,
-			" actualΔ=", h_a-h_t,
-			" u_a/u_g=", u_a/u_g,
-			"\n")
-	}
-
-	return triggerRatio
-}
-
-// enlistWorker encourages another dedicated mark worker to start on
-// another P if there are spare worker slots. It is used by putfull
-// when more work is made available.
-//
-//go:nowritebarrier
-func (c *gcControllerState) enlistWorker() {
-	// If there are idle Ps, wake one so it will run an idle worker.
-	// NOTE: This is suspected of causing deadlocks. See golang.org/issue/19112.
-	//
-	//	if atomic.Load(&sched.npidle) != 0 && atomic.Load(&sched.nmspinning) == 0 {
-	//		wakep()
-	//		return
-	//	}
-
-	// There are no idle Ps. If we need more dedicated workers,
-	// try to preempt a running P so it will switch to a worker.
-	if c.dedicatedMarkWorkersNeeded <= 0 {
-		return
-	}
-	// Pick a random other P to preempt.
-	if gomaxprocs <= 1 {
-		return
-	}
-	gp := getg()
-	if gp == nil || gp.m == nil || gp.m.p == 0 {
-		return
-	}
-	myID := gp.m.p.ptr().id
-	for tries := 0; tries < 5; tries++ {
-		id := int32(fastrandn(uint32(gomaxprocs - 1)))
-		if id >= myID {
-			id++
-		}
-		p := allp[id]
-		if p.status != _Prunning {
-			continue
-		}
-		if preemptone(p) {
-			return
-		}
-	}
-}
-
-// findRunnableGCWorker returns a background mark worker for _p_ if it
-// should be run. This must only be called when gcBlackenEnabled != 0.
-func (c *gcControllerState) findRunnableGCWorker(_p_ *p) *g {
-	if gcBlackenEnabled == 0 {
-		throw("gcControllerState.findRunnable: blackening not enabled")
-	}
-
-	if !gcMarkWorkAvailable(_p_) {
-		// No work to be done right now. This can happen at
-		// the end of the mark phase when there are still
-		// assists tapering off. Don't bother running a worker
-		// now because it'll just return immediately.
-		return nil
-	}
-
-	// Grab a worker before we commit to running below.
-	node := (*gcBgMarkWorkerNode)(gcBgMarkWorkerPool.pop())
-	if node == nil {
-		// There is at least one worker per P, so normally there are
-		// enough workers to run on all Ps, if necessary. However, once
-		// a worker enters gcMarkDone it may park without rejoining the
-		// pool, thus freeing a P with no corresponding worker.
-		// gcMarkDone never depends on another worker doing work, so it
-		// is safe to simply do nothing here.
-		//
-		// If gcMarkDone bails out without completing the mark phase,
-		// it will always do so with queued global work. Thus, that P
-		// will be immediately eligible to re-run the worker G it was
-		// just using, ensuring work can complete.
-		return nil
-	}
-
-	decIfPositive := func(ptr *int64) bool {
-		for {
-			v := atomic.Loadint64(ptr)
-			if v <= 0 {
-				return false
-			}
-
-			if atomic.Casint64(ptr, v, v-1) {
-				return true
-			}
-		}
-	}
-
-	if decIfPositive(&c.dedicatedMarkWorkersNeeded) {
-		// This P is now dedicated to marking until the end of
-		// the concurrent mark phase.
-		_p_.gcMarkWorkerMode = gcMarkWorkerDedicatedMode
-	} else if c.fractionalUtilizationGoal == 0 {
-		// No need for fractional workers.
-		gcBgMarkWorkerPool.push(&node.node)
-		return nil
-	} else {
-		// Is this P behind on the fractional utilization
-		// goal?
-		//
-		// This should be kept in sync with pollFractionalWorkerExit.
-		delta := nanotime() - c.markStartTime
-		if delta > 0 && float64(_p_.gcFractionalMarkTime)/float64(delta) > c.fractionalUtilizationGoal {
-			// Nope. No need to run a fractional worker.
-			gcBgMarkWorkerPool.push(&node.node)
-			return nil
-		}
-		// Run a fractional worker.
-		_p_.gcMarkWorkerMode = gcMarkWorkerFractionalMode
-	}
-
-	// Run the background mark worker.
-	gp := node.gp.ptr()
-	casgstatus(gp, _Gwaiting, _Grunnable)
-	if trace.enabled {
-		traceGoUnpark(gp, 0)
-	}
-	return gp
-}
-
-// resetLive sets up the controller state for the next mark phase after the end
-// of the previous one. Must be called after endCycle and before commit, before
-// the world is started.
-//
-// The world must be stopped.
-func (c *gcControllerState) resetLive(bytesMarked uint64) {
-	c.heapMarked = bytesMarked
-	c.heapLive = bytesMarked
-	c.heapScan = uint64(c.heapScanWork.Load())
-	c.lastHeapScan = uint64(c.heapScanWork.Load())
-
-	// heapLive was updated, so emit a trace event.
-	if trace.enabled {
-		traceHeapAlloc()
-	}
-}
-
-// logWorkTime updates mark work accounting in the controller by a duration of
-// work in nanoseconds.
-//
-// Safe to execute at any time.
-func (c *gcControllerState) logWorkTime(mode gcMarkWorkerMode, duration int64) {
-	switch mode {
-	case gcMarkWorkerDedicatedMode:
-		atomic.Xaddint64(&c.dedicatedMarkTime, duration)
-		atomic.Xaddint64(&c.dedicatedMarkWorkersNeeded, 1)
-	case gcMarkWorkerFractionalMode:
-		atomic.Xaddint64(&c.fractionalMarkTime, duration)
-	case gcMarkWorkerIdleMode:
-		atomic.Xaddint64(&c.idleMarkTime, duration)
-	default:
-		throw("logWorkTime: unknown mark worker mode")
-	}
-}
-
-func (c *gcControllerState) update(dHeapLive, dHeapScan int64) {
-	if dHeapLive != 0 {
-		atomic.Xadd64(&gcController.heapLive, dHeapLive)
-		if trace.enabled {
-			// gcController.heapLive changed.
-			traceHeapAlloc()
-		}
-	}
-	// Only update heapScan in the new pacer redesign if we're not
-	// currently in a GC.
-	if !goexperiment.PacerRedesign || gcBlackenEnabled == 0 {
-		if dHeapScan != 0 {
-			atomic.Xadd64(&gcController.heapScan, dHeapScan)
-		}
-	}
-	if gcBlackenEnabled != 0 {
-		// gcController.heapLive and heapScan changed.
-		c.revise()
-	}
-}
-
-func (c *gcControllerState) addScannableStack(pp *p, amount int64) {
-	if pp == nil {
-		atomic.Xadd64(&c.scannableStackSize, amount)
-		return
-	}
-	pp.scannableStackSizeDelta += amount
-	if pp.scannableStackSizeDelta >= scannableStackSizeSlack || pp.scannableStackSizeDelta <= -scannableStackSizeSlack {
-		atomic.Xadd64(&c.scannableStackSize, pp.scannableStackSizeDelta)
-		pp.scannableStackSizeDelta = 0
-	}
-}
-
-func (c *gcControllerState) addGlobals(amount int64) {
-	atomic.Xadd64(&c.globalsScan, amount)
-}
-
-// commit recomputes all pacing parameters from scratch, namely
-// absolute trigger, the heap goal, mark pacing, and sweep pacing.
-//
-// If goexperiment.PacerRedesign is true, triggerRatio is ignored.
-//
-// This can be called any time. If GC is the in the middle of a
-// concurrent phase, it will adjust the pacing of that phase.
-//
-// This depends on gcPercent, gcController.heapMarked, and
-// gcController.heapLive. These must be up to date.
-//
-// mheap_.lock must be held or the world must be stopped.
-func (c *gcControllerState) commit(triggerRatio float64) {
-	if !c.test {
-		assertWorldStoppedOrLockHeld(&mheap_.lock)
-	}
-
-	if !goexperiment.PacerRedesign {
-		c.oldCommit(triggerRatio)
-		return
-	}
-
-	// Compute the next GC goal, which is when the allocated heap
-	// has grown by GOGC/100 over where it started the last cycle,
-	// plus additional runway for non-heap sources of GC work.
-	goal := ^uint64(0)
-	if gcPercent := c.gcPercent.Load(); gcPercent >= 0 {
-		goal = c.heapMarked + (c.heapMarked+atomic.Load64(&c.stackScan)+atomic.Load64(&c.globalsScan))*uint64(gcPercent)/100
-	}
-
-	// Don't trigger below the minimum heap size.
-	minTrigger := c.heapMinimum
-	if !isSweepDone() {
-		// Concurrent sweep happens in the heap growth
-		// from gcController.heapLive to trigger, so ensure
-		// that concurrent sweep has some heap growth
-		// in which to perform sweeping before we
-		// start the next GC cycle.
-		sweepMin := atomic.Load64(&c.heapLive) + sweepMinHeapDistance
-		if sweepMin > minTrigger {
-			minTrigger = sweepMin
-		}
-	}
-
-	// If we let the trigger go too low, then if the application
-	// is allocating very rapidly we might end up in a situation
-	// where we're allocating black during a nearly always-on GC.
-	// The result of this is a growing heap and ultimately an
-	// increase in RSS. By capping us at a point >0, we're essentially
-	// saying that we're OK using more CPU during the GC to prevent
-	// this growth in RSS.
-	//
-	// The current constant was chosen empirically: given a sufficiently
-	// fast/scalable allocator with 48 Ps that could drive the trigger ratio
-	// to <0.05, this constant causes applications to retain the same peak
-	// RSS compared to not having this allocator.
-	if triggerBound := uint64(0.7*float64(goal-c.heapMarked)) + c.heapMarked; minTrigger < triggerBound {
-		minTrigger = triggerBound
-	}
-
-	// For small heaps, set the max trigger point at 95% of the heap goal.
-	// This ensures we always have *some* headroom when the GC actually starts.
-	// For larger heaps, set the max trigger point at the goal, minus the
-	// minimum heap size.
-	// This choice follows from the fact that the minimum heap size is chosen
-	// to reflect the costs of a GC with no work to do. With a large heap but
-	// very little scan work to perform, this gives us exactly as much runway
-	// as we would need, in the worst case.
-	maxRunway := uint64(0.95 * float64(goal-c.heapMarked))
-	if largeHeapMaxRunway := goal - c.heapMinimum; goal > c.heapMinimum && maxRunway < largeHeapMaxRunway {
-		maxRunway = largeHeapMaxRunway
-	}
-	maxTrigger := maxRunway + c.heapMarked
-	if maxTrigger < minTrigger {
-		maxTrigger = minTrigger
-	}
-
-	// Compute the trigger by using our estimate of the cons/mark ratio.
-	//
-	// The idea is to take our expected scan work, and multiply it by
-	// the cons/mark ratio to determine how long it'll take to complete
-	// that scan work in terms of bytes allocated. This gives us our GC's
-	// runway.
-	//
-	// However, the cons/mark ratio is a ratio of rates per CPU-second, but
-	// here we care about the relative rates for some division of CPU
-	// resources among the mutator and the GC.
-	//
-	// To summarize, we have B / cpu-ns, and we want B / ns. We get that
-	// by multiplying by our desired division of CPU resources. We choose
-	// to express CPU resources as GOMAPROCS*fraction. Note that because
-	// we're working with a ratio here, we can omit the number of CPU cores,
-	// because they'll appear in the numerator and denominator and cancel out.
-	// As a result, this is basically just "weighing" the cons/mark ratio by
-	// our desired division of resources.
-	//
-	// Furthermore, by setting the trigger so that CPU resources are divided
-	// this way, assuming that the cons/mark ratio is correct, we make that
-	// division a reality.
-	var trigger uint64
-	runway := uint64((c.consMark * (1 - gcGoalUtilization) / (gcGoalUtilization)) * float64(c.lastHeapScan+c.stackScan+c.globalsScan))
-	if runway > goal {
-		trigger = minTrigger
-	} else {
-		trigger = goal - runway
-	}
-	if trigger < minTrigger {
-		trigger = minTrigger
-	}
-	if trigger > maxTrigger {
-		trigger = maxTrigger
-	}
-	if trigger > goal {
-		goal = trigger
-	}
-
-	// Commit to the trigger and goal.
-	c.trigger = trigger
-	atomic.Store64(&c.heapGoal, goal)
-	if trace.enabled {
-		traceHeapGoal()
-	}
-
-	// Update mark pacing.
-	if gcphase != _GCoff {
-		c.revise()
-	}
-}
-
-// oldCommit sets the trigger ratio and updates everything
-// derived from it: the absolute trigger, the heap goal, mark pacing,
-// and sweep pacing.
-//
-// This can be called any time. If GC is the in the middle of a
-// concurrent phase, it will adjust the pacing of that phase.
-//
-// This depends on gcPercent, gcController.heapMarked, and
-// gcController.heapLive. These must be up to date.
-//
-// For !goexperiment.PacerRedesign.
-func (c *gcControllerState) oldCommit(triggerRatio float64) {
-	gcPercent := c.gcPercent.Load()
-
-	// Compute the next GC goal, which is when the allocated heap
-	// has grown by GOGC/100 over the heap marked by the last
-	// cycle.
-	goal := ^uint64(0)
-	if gcPercent >= 0 {
-		goal = c.heapMarked + c.heapMarked*uint64(gcPercent)/100
-	}
-
-	// Set the trigger ratio, capped to reasonable bounds.
-	if gcPercent >= 0 {
-		scalingFactor := float64(gcPercent) / 100
-		// Ensure there's always a little margin so that the
-		// mutator assist ratio isn't infinity.
-		maxTriggerRatio := 0.95 * scalingFactor
-		if triggerRatio > maxTriggerRatio {
-			triggerRatio = maxTriggerRatio
-		}
-
-		// If we let triggerRatio go too low, then if the application
-		// is allocating very rapidly we might end up in a situation
-		// where we're allocating black during a nearly always-on GC.
-		// The result of this is a growing heap and ultimately an
-		// increase in RSS. By capping us at a point >0, we're essentially
-		// saying that we're OK using more CPU during the GC to prevent
-		// this growth in RSS.
-		//
-		// The current constant was chosen empirically: given a sufficiently
-		// fast/scalable allocator with 48 Ps that could drive the trigger ratio
-		// to <0.05, this constant causes applications to retain the same peak
-		// RSS compared to not having this allocator.
-		minTriggerRatio := 0.6 * scalingFactor
-		if triggerRatio < minTriggerRatio {
-			triggerRatio = minTriggerRatio
-		}
-	} else if triggerRatio < 0 {
-		// gcPercent < 0, so just make sure we're not getting a negative
-		// triggerRatio. This case isn't expected to happen in practice,
-		// and doesn't really matter because if gcPercent < 0 then we won't
-		// ever consume triggerRatio further on in this function, but let's
-		// just be defensive here; the triggerRatio being negative is almost
-		// certainly undesirable.
-		triggerRatio = 0
-	}
-	c.triggerRatio = triggerRatio
-
-	// Compute the absolute GC trigger from the trigger ratio.
-	//
-	// We trigger the next GC cycle when the allocated heap has
-	// grown by the trigger ratio over the marked heap size.
-	trigger := ^uint64(0)
-	if gcPercent >= 0 {
-		trigger = uint64(float64(c.heapMarked) * (1 + triggerRatio))
-		// Don't trigger below the minimum heap size.
-		minTrigger := c.heapMinimum
-		if !isSweepDone() {
-			// Concurrent sweep happens in the heap growth
-			// from gcController.heapLive to trigger, so ensure
-			// that concurrent sweep has some heap growth
-			// in which to perform sweeping before we
-			// start the next GC cycle.
-			sweepMin := atomic.Load64(&c.heapLive) + sweepMinHeapDistance
-			if sweepMin > minTrigger {
-				minTrigger = sweepMin
-			}
-		}
-		if trigger < minTrigger {
-			trigger = minTrigger
-		}
-		if int64(trigger) < 0 {
-			print("runtime: heapGoal=", c.heapGoal, " heapMarked=", c.heapMarked, " gcController.heapLive=", c.heapLive, " initialHeapLive=", work.initialHeapLive, "triggerRatio=", triggerRatio, " minTrigger=", minTrigger, "\n")
-			throw("trigger underflow")
-		}
-		if trigger > goal {
-			// The trigger ratio is always less than GOGC/100, but
-			// other bounds on the trigger may have raised it.
-			// Push up the goal, too.
-			goal = trigger
-		}
-	}
-
-	// Commit to the trigger and goal.
-	c.trigger = trigger
-	atomic.Store64(&c.heapGoal, goal)
-	if trace.enabled {
-		traceHeapGoal()
-	}
-
-	// Update mark pacing.
-	if gcphase != _GCoff {
-		c.revise()
-	}
-}
-
-// effectiveGrowthRatio returns the current effective heap growth
-// ratio (GOGC/100) based on heapMarked from the previous GC and
-// heapGoal for the current GC.
-//
-// This may differ from gcPercent/100 because of various upper and
-// lower bounds on gcPercent. For example, if the heap is smaller than
-// heapMinimum, this can be higher than gcPercent/100.
-//
-// mheap_.lock must be held or the world must be stopped.
-func (c *gcControllerState) effectiveGrowthRatio() float64 {
-	if !c.test {
-		assertWorldStoppedOrLockHeld(&mheap_.lock)
-	}
-
-	egogc := float64(atomic.Load64(&c.heapGoal)-c.heapMarked) / float64(c.heapMarked)
-	if egogc < 0 {
-		// Shouldn't happen, but just in case.
-		egogc = 0
-	}
-	return egogc
-}
-
-// setGCPercent updates gcPercent and all related pacer state.
-// Returns the old value of gcPercent.
-//
-// Calls gcControllerState.commit.
-//
-// The world must be stopped, or mheap_.lock must be held.
-func (c *gcControllerState) setGCPercent(in int32) int32 {
-	if !c.test {
-		assertWorldStoppedOrLockHeld(&mheap_.lock)
-	}
-
-	out := c.gcPercent.Load()
-	if in < 0 {
-		in = -1
-	}
-	c.heapMinimum = defaultHeapMinimum * uint64(in) / 100
-	c.gcPercent.Store(in)
-	// Update pacing in response to gcPercent change.
-	c.commit(c.triggerRatio)
-
-	return out
-}
-
-//go:linkname setGCPercent runtime/debug.setGCPercent
-func setGCPercent(in int32) (out int32) {
-	// Run on the system stack since we grab the heap lock.
-	systemstack(func() {
-		lock(&mheap_.lock)
-		out = gcController.setGCPercent(in)
-		gcPaceSweeper(gcController.trigger)
-		gcPaceScavenger(gcController.heapGoal, gcController.lastHeapGoal)
-		unlock(&mheap_.lock)
-	})
-
-	// If we just disabled GC, wait for any concurrent GC mark to
-	// finish so we always return with no GC running.
-	if in < 0 {
-		gcWaitOnMark(atomic.Load(&work.cycles))
-	}
-
-	return out
-}
-
-func readGOGC() int32 {
-	p := gogetenv("GOGC")
-	if p == "off" {
-		return -1
-	}
-	if n, ok := atoi32(p); ok {
-		return n
-	}
-	return 100
-}
-
-type piController struct {
-	kp float64 // Proportional constant.
-	ti float64 // Integral time constant.
-	tt float64 // Reset time.
-
-	min, max float64 // Output boundaries.
-
-	// PI controller state.
-
-	errIntegral float64 // Integral of the error from t=0 to now.
-
-	// Error flags.
-	errOverflow   bool // Set if errIntegral ever overflowed.
-	inputOverflow bool // Set if an operation with the input overflowed.
-}
-
-// next provides a new sample to the controller.
-//
-// input is the sample, setpoint is the desired point, and period is how much
-// time (in whatever unit makes the most sense) has passed since the last sample.
-//
-// Returns a new value for the variable it's controlling, and whether the operation
-// completed successfully. One reason this might fail is if error has been growing
-// in an unbounded manner, to the point of overflow.
-//
-// In the specific case of an error overflow occurs, the errOverflow field will be
-// set and the rest of the controller's internal state will be fully reset.
-func (c *piController) next(input, setpoint, period float64) (float64, bool) {
-	// Compute the raw output value.
-	prop := c.kp * (setpoint - input)
-	rawOutput := prop + c.errIntegral
-
-	// Clamp rawOutput into output.
-	output := rawOutput
-	if isInf(output) || isNaN(output) {
-		// The input had a large enough magnitude that either it was already
-		// overflowed, or some operation with it overflowed.
-		// Set a flag and reset. That's the safest thing to do.
-		c.reset()
-		c.inputOverflow = true
-		return c.min, false
-	}
-	if output < c.min {
-		output = c.min
-	} else if output > c.max {
-		output = c.max
-	}
-
-	// Update the controller's state.
-	if c.ti != 0 && c.tt != 0 {
-		c.errIntegral += (c.kp*period/c.ti)*(setpoint-input) + (period/c.tt)*(output-rawOutput)
-		if isInf(c.errIntegral) || isNaN(c.errIntegral) {
-			// So much error has accumulated that we managed to overflow.
-			// The assumptions around the controller have likely broken down.
-			// Set a flag and reset. That's the safest thing to do.
-			c.reset()
-			c.errOverflow = true
-			return c.min, false
-		}
-	}
-	return output, true
-}
-
-// reset resets the controller state, except for controller error flags.
-func (c *piController) reset() {
-	c.errIntegral = 0
-}
diff --git a/contrib/go/_std_1.18/src/runtime/mgcscavenge.go b/contrib/go/_std_1.18/src/runtime/mgcscavenge.go
deleted file mode 100644
index 5f50378adf..0000000000
--- a/contrib/go/_std_1.18/src/runtime/mgcscavenge.go
+++ /dev/null
@@ -1,1008 +0,0 @@
-// Copyright 2019 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Scavenging free pages.
-//
-// This file implements scavenging (the release of physical pages backing mapped
-// memory) of free and unused pages in the heap as a way to deal with page-level
-// fragmentation and reduce the RSS of Go applications.
-//
-// Scavenging in Go happens on two fronts: there's the background
-// (asynchronous) scavenger and the heap-growth (synchronous) scavenger.
-//
-// The former happens on a goroutine much like the background sweeper which is
-// soft-capped at using scavengePercent of the mutator's time, based on
-// order-of-magnitude estimates of the costs of scavenging. The background
-// scavenger's primary goal is to bring the estimated heap RSS of the
-// application down to a goal.
-//
-// That goal is defined as:
-//   (retainExtraPercent+100) / 100 * (heapGoal / lastHeapGoal) * last_heap_inuse
-//
-// Essentially, we wish to have the application's RSS track the heap goal, but
-// the heap goal is defined in terms of bytes of objects, rather than pages like
-// RSS. As a result, we need to take into account for fragmentation internal to
-// spans. heapGoal / lastHeapGoal defines the ratio between the current heap goal
-// and the last heap goal, which tells us by how much the heap is growing and
-// shrinking. We estimate what the heap will grow to in terms of pages by taking
-// this ratio and multiplying it by heap_inuse at the end of the last GC, which
-// allows us to account for this additional fragmentation. Note that this
-// procedure makes the assumption that the degree of fragmentation won't change
-// dramatically over the next GC cycle. Overestimating the amount of
-// fragmentation simply results in higher memory use, which will be accounted
-// for by the next pacing up date. Underestimating the fragmentation however
-// could lead to performance degradation. Handling this case is not within the
-// scope of the scavenger. Situations where the amount of fragmentation balloons
-// over the course of a single GC cycle should be considered pathologies,
-// flagged as bugs, and fixed appropriately.
-//
-// An additional factor of retainExtraPercent is added as a buffer to help ensure
-// that there's more unscavenged memory to allocate out of, since each allocation
-// out of scavenged memory incurs a potentially expensive page fault.
-//
-// The goal is updated after each GC and the scavenger's pacing parameters
-// (which live in mheap_) are updated to match. The pacing parameters work much
-// like the background sweeping parameters. The parameters define a line whose
-// horizontal axis is time and vertical axis is estimated heap RSS, and the
-// scavenger attempts to stay below that line at all times.
-//
-// The synchronous heap-growth scavenging happens whenever the heap grows in
-// size, for some definition of heap-growth. The intuition behind this is that
-// the application had to grow the heap because existing fragments were
-// not sufficiently large to satisfy a page-level memory allocation, so we
-// scavenge those fragments eagerly to offset the growth in RSS that results.
-
-package runtime
-
-import (
-	"internal/goos"
-	"runtime/internal/atomic"
-	"runtime/internal/sys"
-	"unsafe"
-)
-
-const (
-	// The background scavenger is paced according to these parameters.
-	//
-	// scavengePercent represents the portion of mutator time we're willing
-	// to spend on scavenging in percent.
-	scavengePercent = 1 // 1%
-
-	// retainExtraPercent represents the amount of memory over the heap goal
-	// that the scavenger should keep as a buffer space for the allocator.
-	//
-	// The purpose of maintaining this overhead is to have a greater pool of
-	// unscavenged memory available for allocation (since using scavenged memory
-	// incurs an additional cost), to account for heap fragmentation and
-	// the ever-changing layout of the heap.
-	retainExtraPercent = 10
-
-	// maxPagesPerPhysPage is the maximum number of supported runtime pages per
-	// physical page, based on maxPhysPageSize.
-	maxPagesPerPhysPage = maxPhysPageSize / pageSize
-
-	// scavengeCostRatio is the approximate ratio between the costs of using previously
-	// scavenged memory and scavenging memory.
-	//
-	// For most systems the cost of scavenging greatly outweighs the costs
-	// associated with using scavenged memory, making this constant 0. On other systems
-	// (especially ones where "sysUsed" is not just a no-op) this cost is non-trivial.
-	//
-	// This ratio is used as part of multiplicative factor to help the scavenger account
-	// for the additional costs of using scavenged memory in its pacing.
-	scavengeCostRatio = 0.7 * (goos.IsDarwin + goos.IsIos)
-
-	// scavengeReservationShards determines the amount of memory the scavenger
-	// should reserve for scavenging at a time. Specifically, the amount of
-	// memory reserved is (heap size in bytes) / scavengeReservationShards.
-	scavengeReservationShards = 64
-)
-
-// heapRetained returns an estimate of the current heap RSS.
-func heapRetained() uint64 {
-	return memstats.heap_sys.load() - atomic.Load64(&memstats.heap_released)
-}
-
-// gcPaceScavenger updates the scavenger's pacing, particularly
-// its rate and RSS goal. For this, it requires the current heapGoal,
-// and the heapGoal for the previous GC cycle.
-//
-// The RSS goal is based on the current heap goal with a small overhead
-// to accommodate non-determinism in the allocator.
-//
-// The pacing is based on scavengePageRate, which applies to both regular and
-// huge pages. See that constant for more information.
-//
-// Must be called whenever GC pacing is updated.
-//
-// mheap_.lock must be held or the world must be stopped.
-func gcPaceScavenger(heapGoal, lastHeapGoal uint64) {
-	assertWorldStoppedOrLockHeld(&mheap_.lock)
-
-	// If we're called before the first GC completed, disable scavenging.
-	// We never scavenge before the 2nd GC cycle anyway (we don't have enough
-	// information about the heap yet) so this is fine, and avoids a fault
-	// or garbage data later.
-	if lastHeapGoal == 0 {
-		atomic.Store64(&mheap_.scavengeGoal, ^uint64(0))
-		return
-	}
-	// Compute our scavenging goal.
-	goalRatio := float64(heapGoal) / float64(lastHeapGoal)
-	retainedGoal := uint64(float64(memstats.last_heap_inuse) * goalRatio)
-	// Add retainExtraPercent overhead to retainedGoal. This calculation
-	// looks strange but the purpose is to arrive at an integer division
-	// (e.g. if retainExtraPercent = 12.5, then we get a divisor of 8)
-	// that also avoids the overflow from a multiplication.
-	retainedGoal += retainedGoal / (1.0 / (retainExtraPercent / 100.0))
-	// Align it to a physical page boundary to make the following calculations
-	// a bit more exact.
-	retainedGoal = (retainedGoal + uint64(physPageSize) - 1) &^ (uint64(physPageSize) - 1)
-
-	// Represents where we are now in the heap's contribution to RSS in bytes.
-	//
-	// Guaranteed to always be a multiple of physPageSize on systems where
-	// physPageSize <= pageSize since we map heap_sys at a rate larger than
-	// any physPageSize and released memory in multiples of the physPageSize.
-	//
-	// However, certain functions recategorize heap_sys as other stats (e.g.
-	// stack_sys) and this happens in multiples of pageSize, so on systems
-	// where physPageSize > pageSize the calculations below will not be exact.
-	// Generally this is OK since we'll be off by at most one regular
-	// physical page.
-	retainedNow := heapRetained()
-
-	// If we're already below our goal, or within one page of our goal, then disable
-	// the background scavenger. We disable the background scavenger if there's
-	// less than one physical page of work to do because it's not worth it.
-	if retainedNow <= retainedGoal || retainedNow-retainedGoal < uint64(physPageSize) {
-		atomic.Store64(&mheap_.scavengeGoal, ^uint64(0))
-		return
-	}
-	atomic.Store64(&mheap_.scavengeGoal, retainedGoal)
-}
-
-// Sleep/wait state of the background scavenger.
-var scavenge struct {
-	lock                 mutex
-	g                    *g
-	parked               bool
-	timer                *timer
-	sysmonWake           uint32 // Set atomically.
-	printControllerReset bool   // Whether the scavenger is in cooldown.
-}
-
-// readyForScavenger signals sysmon to wake the scavenger because
-// there may be new work to do.
-//
-// There may be a significant delay between when this function runs
-// and when the scavenger is kicked awake, but it may be safely invoked
-// in contexts where wakeScavenger is unsafe to call directly.
-func readyForScavenger() {
-	atomic.Store(&scavenge.sysmonWake, 1)
-}
-
-// wakeScavenger immediately unparks the scavenger if necessary.
-//
-// May run without a P, but it may allocate, so it must not be called
-// on any allocation path.
-//
-// mheap_.lock, scavenge.lock, and sched.lock must not be held.
-func wakeScavenger() {
-	lock(&scavenge.lock)
-	if scavenge.parked {
-		// Notify sysmon that it shouldn't bother waking up the scavenger.
-		atomic.Store(&scavenge.sysmonWake, 0)
-
-		// Try to stop the timer but we don't really care if we succeed.
-		// It's possible that either a timer was never started, or that
-		// we're racing with it.
-		// In the case that we're racing with there's the low chance that
-		// we experience a spurious wake-up of the scavenger, but that's
-		// totally safe.
-		stopTimer(scavenge.timer)
-
-		// Unpark the goroutine and tell it that there may have been a pacing
-		// change. Note that we skip the scheduler's runnext slot because we
-		// want to avoid having the scavenger interfere with the fair
-		// scheduling of user goroutines. In effect, this schedules the
-		// scavenger at a "lower priority" but that's OK because it'll
-		// catch up on the work it missed when it does get scheduled.
-		scavenge.parked = false
-
-		// Ready the goroutine by injecting it. We use injectglist instead
-		// of ready or goready in order to allow us to run this function
-		// without a P. injectglist also avoids placing the goroutine in
-		// the current P's runnext slot, which is desirable to prevent
-		// the scavenger from interfering with user goroutine scheduling
-		// too much.
-		var list gList
-		list.push(scavenge.g)
-		injectglist(&list)
-	}
-	unlock(&scavenge.lock)
-}
-
-// scavengeSleep attempts to put the scavenger to sleep for ns.
-//
-// Note that this function should only be called by the scavenger.
-//
-// The scavenger may be woken up earlier by a pacing change, and it may not go
-// to sleep at all if there's a pending pacing change.
-//
-// Returns the amount of time actually slept.
-func scavengeSleep(ns int64) int64 {
-	lock(&scavenge.lock)
-
-	// Set the timer.
-	//
-	// This must happen here instead of inside gopark
-	// because we can't close over any variables without
-	// failing escape analysis.
-	start := nanotime()
-	resetTimer(scavenge.timer, start+ns)
-
-	// Mark ourself as asleep and go to sleep.
-	scavenge.parked = true
-	goparkunlock(&scavenge.lock, waitReasonSleep, traceEvGoSleep, 2)
-
-	// Return how long we actually slept for.
-	return nanotime() - start
-}
-
-// Background scavenger.
-//
-// The background scavenger maintains the RSS of the application below
-// the line described by the proportional scavenging statistics in
-// the mheap struct.
-func bgscavenge(c chan int) {
-	scavenge.g = getg()
-
-	lockInit(&scavenge.lock, lockRankScavenge)
-	lock(&scavenge.lock)
-	scavenge.parked = true
-
-	scavenge.timer = new(timer)
-	scavenge.timer.f = func(_ any, _ uintptr) {
-		wakeScavenger()
-	}
-
-	c <- 1
-	goparkunlock(&scavenge.lock, waitReasonGCScavengeWait, traceEvGoBlock, 1)
-
-	// idealFraction is the ideal % of overall application CPU time that we
-	// spend scavenging.
-	idealFraction := float64(scavengePercent) / 100.0
-
-	// Input: fraction of CPU time used.
-	// Setpoint: idealFraction.
-	// Output: ratio of critical time to sleep time (determines sleep time).
-	//
-	// The output of this controller is somewhat indirect to what we actually
-	// want to achieve: how much time to sleep for. The reason for this definition
-	// is to ensure that the controller's outputs have a direct relationship with
-	// its inputs (as opposed to an inverse relationship), making it somewhat
-	// easier to reason about for tuning purposes.
-	critSleepController := piController{
-		// Tuned loosely via Ziegler-Nichols process.
-		kp: 0.3375,
-		ti: 3.2e6,
-		tt: 1e9, // 1 second reset time.
-
-		// These ranges seem wide, but we want to give the controller plenty of
-		// room to hunt for the optimal value.
-		min: 0.001,  // 1:1000
-		max: 1000.0, // 1000:1
-	}
-	// It doesn't really matter what value we start at, but we can't be zero, because
-	// that'll cause divide-by-zero issues. Pick something conservative which we'll
-	// also use as a fallback.
-	const startingCritSleepRatio = 0.001
-	critSleepRatio := startingCritSleepRatio
-	// Duration left in nanoseconds during which we avoid using the controller and
-	// we hold critSleepRatio at a conservative value. Used if the controller's
-	// assumptions fail to hold.
-	controllerCooldown := int64(0)
-	for {
-		released := uintptr(0)
-		crit := float64(0)
-
-		// Spend at least 1 ms scavenging, otherwise the corresponding
-		// sleep time to maintain our desired utilization is too low to
-		// be reliable.
-		const minCritTime = 1e6
-		for crit < minCritTime {
-			// If background scavenging is disabled or if there's no work to do just park.
-			retained, goal := heapRetained(), atomic.Load64(&mheap_.scavengeGoal)
-			if retained <= goal {
-				break
-			}
-
-			// scavengeQuantum is the amount of memory we try to scavenge
-			// in one go. A smaller value means the scavenger is more responsive
-			// to the scheduler in case of e.g. preemption. A larger value means
-			// that the overheads of scavenging are better amortized, so better
-			// scavenging throughput.
-			//
-			// The current value is chosen assuming a cost of ~10µs/physical page
-			// (this is somewhat pessimistic), which implies a worst-case latency of
-			// about 160µs for 4 KiB physical pages. The current value is biased
-			// toward latency over throughput.
-			const scavengeQuantum = 64 << 10
-
-			// Accumulate the amount of time spent scavenging.
-			start := nanotime()
-			r := mheap_.pages.scavenge(scavengeQuantum)
-			atomic.Xadduintptr(&mheap_.pages.scav.released, r)
-			end := nanotime()
-
-			// On some platforms we may see end >= start if the time it takes to scavenge
-			// memory is less than the minimum granularity of its clock (e.g. Windows) or
-			// due to clock bugs.
-			//
-			// In this case, just assume scavenging takes 10 µs per regular physical page
-			// (determined empirically), and conservatively ignore the impact of huge pages
-			// on timing.
-			const approxCritNSPerPhysicalPage = 10e3
-			if end <= start {
-				crit += approxCritNSPerPhysicalPage * float64(r/physPageSize)
-			} else {
-				crit += float64(end - start)
-			}
-			released += r
-
-			// When using fake time just do one loop.
-			if faketime != 0 {
-				break
-			}
-		}
-
-		if released == 0 {
-			lock(&scavenge.lock)
-			scavenge.parked = true
-			goparkunlock(&scavenge.lock, waitReasonGCScavengeWait, traceEvGoBlock, 1)
-			continue
-		}
-
-		if released < physPageSize {
-			// If this happens, it means that we may have attempted to release part
-			// of a physical page, but the likely effect of that is that it released
-			// the whole physical page, some of which may have still been in-use.
-			// This could lead to memory corruption. Throw.
-			throw("released less than one physical page of memory")
-		}
-
-		if crit < minCritTime {
-			// This means there wasn't enough work to actually fill up minCritTime.
-			// That's fine; we shouldn't try to do anything with this information
-			// because it's going result in a short enough sleep request that things
-			// will get messy. Just assume we did at least this much work.
-			// All this means is that we'll sleep longer than we otherwise would have.
-			crit = minCritTime
-		}
-
-		// Multiply the critical time by 1 + the ratio of the costs of using
-		// scavenged memory vs. scavenging memory. This forces us to pay down
-		// the cost of reusing this memory eagerly by sleeping for a longer period
-		// of time and scavenging less frequently. More concretely, we avoid situations
-		// where we end up scavenging so often that we hurt allocation performance
-		// because of the additional overheads of using scavenged memory.
-		crit *= 1 + scavengeCostRatio
-
-		// Go to sleep based on how much time we spent doing work.
-		slept := scavengeSleep(int64(crit / critSleepRatio))
-
-		// Stop here if we're cooling down from the controller.
-		if controllerCooldown > 0 {
-			// crit and slept aren't exact measures of time, but it's OK to be a bit
-			// sloppy here. We're just hoping we're avoiding some transient bad behavior.
-			t := slept + int64(crit)
-			if t > controllerCooldown {
-				controllerCooldown = 0
-			} else {
-				controllerCooldown -= t
-			}
-			continue
-		}
-
-		// Calculate the CPU time spent.
-		//
-		// This may be slightly inaccurate with respect to GOMAXPROCS, but we're
-		// recomputing this often enough relative to GOMAXPROCS changes in general
-		// (it only changes when the world is stopped, and not during a GC) that
-		// that small inaccuracy is in the noise.
-		cpuFraction := float64(crit) / ((float64(slept) + crit) * float64(gomaxprocs))
-
-		// Update the critSleepRatio, adjusting until we reach our ideal fraction.
-		var ok bool
-		critSleepRatio, ok = critSleepController.next(cpuFraction, idealFraction, float64(slept)+crit)
-		if !ok {
-			// The core assumption of the controller, that we can get a proportional
-			// response, broke down. This may be transient, so temporarily switch to
-			// sleeping a fixed, conservative amount.
-			critSleepRatio = startingCritSleepRatio
-			controllerCooldown = 5e9 // 5 seconds.
-
-			// Signal the scav trace printer to output this.
-			lock(&scavenge.lock)
-			scavenge.printControllerReset = true
-			unlock(&scavenge.lock)
-		}
-	}
-}
-
-// scavenge scavenges nbytes worth of free pages, starting with the
-// highest address first. Successive calls continue from where it left
-// off until the heap is exhausted. Call scavengeStartGen to bring it
-// back to the top of the heap.
-//
-// Returns the amount of memory scavenged in bytes.
-func (p *pageAlloc) scavenge(nbytes uintptr) uintptr {
-	var (
-		addrs addrRange
-		gen   uint32
-	)
-	released := uintptr(0)
-	for released < nbytes {
-		if addrs.size() == 0 {
-			if addrs, gen = p.scavengeReserve(); addrs.size() == 0 {
-				break
-			}
-		}
-		systemstack(func() {
-			r, a := p.scavengeOne(addrs, nbytes-released)
-			released += r
-			addrs = a
-		})
-	}
-	// Only unreserve the space which hasn't been scavenged or searched
-	// to ensure we always make progress.
-	p.scavengeUnreserve(addrs, gen)
-	return released
-}
-
-// printScavTrace prints a scavenge trace line to standard error.
-//
-// released should be the amount of memory released since the last time this
-// was called, and forced indicates whether the scavenge was forced by the
-// application.
-//
-// scavenge.lock must be held.
-func printScavTrace(gen uint32, released uintptr, forced bool) {
-	assertLockHeld(&scavenge.lock)
-
-	printlock()
-	print("scav ", gen, " ",
-		released>>10, " KiB work, ",
-		atomic.Load64(&memstats.heap_released)>>10, " KiB total, ",
-		(atomic.Load64(&memstats.heap_inuse)*100)/heapRetained(), "% util",
-	)
-	if forced {
-		print(" (forced)")
-	} else if scavenge.printControllerReset {
-		print(" [controller reset]")
-		scavenge.printControllerReset = false
-	}
-	println()
-	printunlock()
-}
-
-// scavengeStartGen starts a new scavenge generation, resetting
-// the scavenger's search space to the full in-use address space.
-//
-// p.mheapLock must be held.
-//
-// Must run on the system stack because p.mheapLock must be held.
-//
-//go:systemstack
-func (p *pageAlloc) scavengeStartGen() {
-	assertLockHeld(p.mheapLock)
-
-	lock(&p.scav.lock)
-	if debug.scavtrace > 0 {
-		printScavTrace(p.scav.gen, atomic.Loaduintptr(&p.scav.released), false)
-	}
-	p.inUse.cloneInto(&p.scav.inUse)
-
-	// Pick the new starting address for the scavenger cycle.
-	var startAddr offAddr
-	if p.scav.scavLWM.lessThan(p.scav.freeHWM) {
-		// The "free" high watermark exceeds the "scavenged" low watermark,
-		// so there are free scavengable pages in parts of the address space
-		// that the scavenger already searched, the high watermark being the
-		// highest one. Pick that as our new starting point to ensure we
-		// see those pages.
-		startAddr = p.scav.freeHWM
-	} else {
-		// The "free" high watermark does not exceed the "scavenged" low
-		// watermark. This means the allocator didn't free any memory in
-		// the range we scavenged last cycle, so we might as well continue
-		// scavenging from where we were.
-		startAddr = p.scav.scavLWM
-	}
-	p.scav.inUse.removeGreaterEqual(startAddr.addr())
-
-	// reservationBytes may be zero if p.inUse.totalBytes is small, or if
-	// scavengeReservationShards is large. This case is fine as the scavenger
-	// will simply be turned off, but it does mean that scavengeReservationShards,
-	// in concert with pallocChunkBytes, dictates the minimum heap size at which
-	// the scavenger triggers. In practice this minimum is generally less than an
-	// arena in size, so virtually every heap has the scavenger on.
-	p.scav.reservationBytes = alignUp(p.inUse.totalBytes, pallocChunkBytes) / scavengeReservationShards
-	p.scav.gen++
-	atomic.Storeuintptr(&p.scav.released, 0)
-	p.scav.freeHWM = minOffAddr
-	p.scav.scavLWM = maxOffAddr
-	unlock(&p.scav.lock)
-}
-
-// scavengeReserve reserves a contiguous range of the address space
-// for scavenging. The maximum amount of space it reserves is proportional
-// to the size of the heap. The ranges are reserved from the high addresses
-// first.
-//
-// Returns the reserved range and the scavenge generation number for it.
-func (p *pageAlloc) scavengeReserve() (addrRange, uint32) {
-	lock(&p.scav.lock)
-	gen := p.scav.gen
-
-	// Start by reserving the minimum.
-	r := p.scav.inUse.removeLast(p.scav.reservationBytes)
-
-	// Return early if the size is zero; we don't want to use
-	// the bogus address below.
-	if r.size() == 0 {
-		unlock(&p.scav.lock)
-		return r, gen
-	}
-
-	// The scavenger requires that base be aligned to a
-	// palloc chunk because that's the unit of operation for
-	// the scavenger, so align down, potentially extending
-	// the range.
-	newBase := alignDown(r.base.addr(), pallocChunkBytes)
-
-	// Remove from inUse however much extra we just pulled out.
-	p.scav.inUse.removeGreaterEqual(newBase)
-	unlock(&p.scav.lock)
-
-	r.base = offAddr{newBase}
-	return r, gen
-}
-
-// scavengeUnreserve returns an unscavenged portion of a range that was
-// previously reserved with scavengeReserve.
-func (p *pageAlloc) scavengeUnreserve(r addrRange, gen uint32) {
-	if r.size() == 0 {
-		return
-	}
-	if r.base.addr()%pallocChunkBytes != 0 {
-		throw("unreserving unaligned region")
-	}
-	lock(&p.scav.lock)
-	if gen == p.scav.gen {
-		p.scav.inUse.add(r)
-	}
-	unlock(&p.scav.lock)
-}
-
-// scavengeOne walks over address range work until it finds
-// a contiguous run of pages to scavenge. It will try to scavenge
-// at most max bytes at once, but may scavenge more to avoid
-// breaking huge pages. Once it scavenges some memory it returns
-// how much it scavenged in bytes.
-//
-// Returns the number of bytes scavenged and the part of work
-// which was not yet searched.
-//
-// work's base address must be aligned to pallocChunkBytes.
-//
-// Must run on the systemstack because it acquires p.mheapLock.
-//
-//go:systemstack
-func (p *pageAlloc) scavengeOne(work addrRange, max uintptr) (uintptr, addrRange) {
-	// Defensively check if we've received an empty address range.
-	// If so, just return.
-	if work.size() == 0 {
-		// Nothing to do.
-		return 0, work
-	}
-	// Check the prerequisites of work.
-	if work.base.addr()%pallocChunkBytes != 0 {
-		throw("scavengeOne called with unaligned work region")
-	}
-	// Calculate the maximum number of pages to scavenge.
-	//
-	// This should be alignUp(max, pageSize) / pageSize but max can and will
-	// be ^uintptr(0), so we need to be very careful not to overflow here.
-	// Rather than use alignUp, calculate the number of pages rounded down
-	// first, then add back one if necessary.
-	maxPages := max / pageSize
-	if max%pageSize != 0 {
-		maxPages++
-	}
-
-	// Calculate the minimum number of pages we can scavenge.
-	//
-	// Because we can only scavenge whole physical pages, we must
-	// ensure that we scavenge at least minPages each time, aligned
-	// to minPages*pageSize.
-	minPages := physPageSize / pageSize
-	if minPages < 1 {
-		minPages = 1
-	}
-
-	// Fast path: check the chunk containing the top-most address in work.
-	if r, w := p.scavengeOneFast(work, minPages, maxPages); r != 0 {
-		return r, w
-	} else {
-		work = w
-	}
-
-	// findCandidate finds the next scavenge candidate in work optimistically.
-	//
-	// Returns the candidate chunk index and true on success, and false on failure.
-	//
-	// The heap need not be locked.
-	findCandidate := func(work addrRange) (chunkIdx, bool) {
-		// Iterate over this work's chunks.
-		for i := chunkIndex(work.limit.addr() - 1); i >= chunkIndex(work.base.addr()); i-- {
-			// If this chunk is totally in-use or has no unscavenged pages, don't bother
-			// doing a more sophisticated check.
-			//
-			// Note we're accessing the summary and the chunks without a lock, but
-			// that's fine. We're being optimistic anyway.
-
-			// Check quickly if there are enough free pages at all.
-			if p.summary[len(p.summary)-1][i].max() < uint(minPages) {
-				continue
-			}
-
-			// Run over the chunk looking harder for a candidate. Again, we could
-			// race with a lot of different pieces of code, but we're just being
-			// optimistic. Make sure we load the l2 pointer atomically though, to
-			// avoid races with heap growth. It may or may not be possible to also
-			// see a nil pointer in this case if we do race with heap growth, but
-			// just defensively ignore the nils. This operation is optimistic anyway.
-			l2 := (*[1 << pallocChunksL2Bits]pallocData)(atomic.Loadp(unsafe.Pointer(&p.chunks[i.l1()])))
-			if l2 != nil && l2[i.l2()].hasScavengeCandidate(minPages) {
-				return i, true
-			}
-		}
-		return 0, false
-	}
-
-	// Slow path: iterate optimistically over the in-use address space
-	// looking for any free and unscavenged page. If we think we see something,
-	// lock and verify it!
-	for work.size() != 0 {
-
-		// Search for the candidate.
-		candidateChunkIdx, ok := findCandidate(work)
-		if !ok {
-			// We didn't find a candidate, so we're done.
-			work.limit = work.base
-			break
-		}
-
-		// Lock, so we can verify what we found.
-		lock(p.mheapLock)
-
-		// Find, verify, and scavenge if we can.
-		chunk := p.chunkOf(candidateChunkIdx)
-		base, npages := chunk.findScavengeCandidate(pallocChunkPages-1, minPages, maxPages)
-		if npages > 0 {
-			work.limit = offAddr{p.scavengeRangeLocked(candidateChunkIdx, base, npages)}
-			unlock(p.mheapLock)
-			return uintptr(npages) * pageSize, work
-		}
-		unlock(p.mheapLock)
-
-		// We were fooled, so let's continue from where we left off.
-		work.limit = offAddr{chunkBase(candidateChunkIdx)}
-	}
-	return 0, work
-}
-
-// scavengeOneFast is the fast path for scavengeOne, which just checks the top
-// chunk of work for some pages to scavenge.
-//
-// Must run on the system stack because it acquires the heap lock.
-//
-//go:systemstack
-func (p *pageAlloc) scavengeOneFast(work addrRange, minPages, maxPages uintptr) (uintptr, addrRange) {
-	maxAddr := work.limit.addr() - 1
-	maxChunk := chunkIndex(maxAddr)
-
-	lock(p.mheapLock)
-	if p.summary[len(p.summary)-1][maxChunk].max() >= uint(minPages) {
-		// We only bother looking for a candidate if there at least
-		// minPages free pages at all.
-		base, npages := p.chunkOf(maxChunk).findScavengeCandidate(chunkPageIndex(maxAddr), minPages, maxPages)
-
-		// If we found something, scavenge it and return!
-		if npages != 0 {
-			work.limit = offAddr{p.scavengeRangeLocked(maxChunk, base, npages)}
-			unlock(p.mheapLock)
-			return uintptr(npages) * pageSize, work
-		}
-	}
-	unlock(p.mheapLock)
-
-	// Update the limit to reflect the fact that we checked maxChunk already.
-	work.limit = offAddr{chunkBase(maxChunk)}
-	return 0, work
-}
-
-// scavengeRangeLocked scavenges the given region of memory.
-// The region of memory is described by its chunk index (ci),
-// the starting page index of the region relative to that
-// chunk (base), and the length of the region in pages (npages).
-//
-// Returns the base address of the scavenged region.
-//
-// p.mheapLock must be held. Unlocks p.mheapLock but reacquires
-// it before returning. Must be run on the systemstack as a result.
-//
-//go:systemstack
-func (p *pageAlloc) scavengeRangeLocked(ci chunkIdx, base, npages uint) uintptr {
-	assertLockHeld(p.mheapLock)
-
-	// Compute the full address for the start of the range.
-	addr := chunkBase(ci) + uintptr(base)*pageSize
-
-	// Mark the range we're about to scavenge as allocated, because
-	// we don't want any allocating goroutines to grab it while
-	// the scavenging is in progress.
-	if scav := p.allocRange(addr, uintptr(npages)); scav != 0 {
-		throw("double scavenge")
-	}
-
-	// With that done, it's safe to unlock.
-	unlock(p.mheapLock)
-
-	// Update the scavenge low watermark.
-	lock(&p.scav.lock)
-	if oAddr := (offAddr{addr}); oAddr.lessThan(p.scav.scavLWM) {
-		p.scav.scavLWM = oAddr
-	}
-	unlock(&p.scav.lock)
-
-	if !p.test {
-		// Only perform the actual scavenging if we're not in a test.
-		// It's dangerous to do so otherwise.
-		sysUnused(unsafe.Pointer(addr), uintptr(npages)*pageSize)
-
-		// Update global accounting only when not in test, otherwise
-		// the runtime's accounting will be wrong.
-		nbytes := int64(npages) * pageSize
-		atomic.Xadd64(&memstats.heap_released, nbytes)
-
-		// Update consistent accounting too.
-		stats := memstats.heapStats.acquire()
-		atomic.Xaddint64(&stats.committed, -nbytes)
-		atomic.Xaddint64(&stats.released, nbytes)
-		memstats.heapStats.release()
-	}
-
-	// Relock the heap, because now we need to make these pages
-	// available allocation. Free them back to the page allocator.
-	lock(p.mheapLock)
-	p.free(addr, uintptr(npages), true)
-
-	// Mark the range as scavenged.
-	p.chunkOf(ci).scavenged.setRange(base, npages)
-	return addr
-}
-
-// fillAligned returns x but with all zeroes in m-aligned
-// groups of m bits set to 1 if any bit in the group is non-zero.
-//
-// For example, fillAligned(0x0100a3, 8) == 0xff00ff.
-//
-// Note that if m == 1, this is a no-op.
-//
-// m must be a power of 2 <= maxPagesPerPhysPage.
-func fillAligned(x uint64, m uint) uint64 {
-	apply := func(x uint64, c uint64) uint64 {
-		// The technique used it here is derived from
-		// https://graphics.stanford.edu/~seander/bithacks.html#ZeroInWord
-		// and extended for more than just bytes (like nibbles
-		// and uint16s) by using an appropriate constant.
-		//
-		// To summarize the technique, quoting from that page:
-		// "[It] works by first zeroing the high bits of the [8]
-		// bytes in the word. Subsequently, it adds a number that
-		// will result in an overflow to the high bit of a byte if
-		// any of the low bits were initially set. Next the high
-		// bits of the original word are ORed with these values;
-		// thus, the high bit of a byte is set iff any bit in the
-		// byte was set. Finally, we determine if any of these high
-		// bits are zero by ORing with ones everywhere except the
-		// high bits and inverting the result."
-		return ^((((x & c) + c) | x) | c)
-	}
-	// Transform x to contain a 1 bit at the top of each m-aligned
-	// group of m zero bits.
-	switch m {
-	case 1:
-		return x
-	case 2:
-		x = apply(x, 0x5555555555555555)
-	case 4:
-		x = apply(x, 0x7777777777777777)
-	case 8:
-		x = apply(x, 0x7f7f7f7f7f7f7f7f)
-	case 16:
-		x = apply(x, 0x7fff7fff7fff7fff)
-	case 32:
-		x = apply(x, 0x7fffffff7fffffff)
-	case 64: // == maxPagesPerPhysPage
-		x = apply(x, 0x7fffffffffffffff)
-	default:
-		throw("bad m value")
-	}
-	// Now, the top bit of each m-aligned group in x is set
-	// that group was all zero in the original x.
-
-	// From each group of m bits subtract 1.
-	// Because we know only the top bits of each
-	// m-aligned group are set, we know this will
-	// set each group to have all the bits set except
-	// the top bit, so just OR with the original
-	// result to set all the bits.
-	return ^((x - (x >> (m - 1))) | x)
-}
-
-// hasScavengeCandidate returns true if there's any min-page-aligned groups of
-// min pages of free-and-unscavenged memory in the region represented by this
-// pallocData.
-//
-// min must be a non-zero power of 2 <= maxPagesPerPhysPage.
-func (m *pallocData) hasScavengeCandidate(min uintptr) bool {
-	if min&(min-1) != 0 || min == 0 {
-		print("runtime: min = ", min, "\n")
-		throw("min must be a non-zero power of 2")
-	} else if min > maxPagesPerPhysPage {
-		print("runtime: min = ", min, "\n")
-		throw("min too large")
-	}
-
-	// The goal of this search is to see if the chunk contains any free and unscavenged memory.
-	for i := len(m.scavenged) - 1; i >= 0; i-- {
-		// 1s are scavenged OR non-free => 0s are unscavenged AND free
-		//
-		// TODO(mknyszek): Consider splitting up fillAligned into two
-		// functions, since here we technically could get by with just
-		// the first half of its computation. It'll save a few instructions
-		// but adds some additional code complexity.
-		x := fillAligned(m.scavenged[i]|m.pallocBits[i], uint(min))
-
-		// Quickly skip over chunks of non-free or scavenged pages.
-		if x != ^uint64(0) {
-			return true
-		}
-	}
-	return false
-}
-
-// findScavengeCandidate returns a start index and a size for this pallocData
-// segment which represents a contiguous region of free and unscavenged memory.
-//
-// searchIdx indicates the page index within this chunk to start the search, but
-// note that findScavengeCandidate searches backwards through the pallocData. As a
-// a result, it will return the highest scavenge candidate in address order.
-//
-// min indicates a hard minimum size and alignment for runs of pages. That is,
-// findScavengeCandidate will not return a region smaller than min pages in size,
-// or that is min pages or greater in size but not aligned to min. min must be
-// a non-zero power of 2 <= maxPagesPerPhysPage.
-//
-// max is a hint for how big of a region is desired. If max >= pallocChunkPages, then
-// findScavengeCandidate effectively returns entire free and unscavenged regions.
-// If max < pallocChunkPages, it may truncate the returned region such that size is
-// max. However, findScavengeCandidate may still return a larger region if, for
-// example, it chooses to preserve huge pages, or if max is not aligned to min (it
-// will round up). That is, even if max is small, the returned size is not guaranteed
-// to be equal to max. max is allowed to be less than min, in which case it is as if
-// max == min.
-func (m *pallocData) findScavengeCandidate(searchIdx uint, min, max uintptr) (uint, uint) {
-	if min&(min-1) != 0 || min == 0 {
-		print("runtime: min = ", min, "\n")
-		throw("min must be a non-zero power of 2")
-	} else if min > maxPagesPerPhysPage {
-		print("runtime: min = ", min, "\n")
-		throw("min too large")
-	}
-	// max may not be min-aligned, so we might accidentally truncate to
-	// a max value which causes us to return a non-min-aligned value.
-	// To prevent this, align max up to a multiple of min (which is always
-	// a power of 2). This also prevents max from ever being less than
-	// min, unless it's zero, so handle that explicitly.
-	if max == 0 {
-		max = min
-	} else {
-		max = alignUp(max, min)
-	}
-
-	i := int(searchIdx / 64)
-	// Start by quickly skipping over blocks of non-free or scavenged pages.
-	for ; i >= 0; i-- {
-		// 1s are scavenged OR non-free => 0s are unscavenged AND free
-		x := fillAligned(m.scavenged[i]|m.pallocBits[i], uint(min))
-		if x != ^uint64(0) {
-			break
-		}
-	}
-	if i < 0 {
-		// Failed to find any free/unscavenged pages.
-		return 0, 0
-	}
-	// We have something in the 64-bit chunk at i, but it could
-	// extend further. Loop until we find the extent of it.
-
-	// 1s are scavenged OR non-free => 0s are unscavenged AND free
-	x := fillAligned(m.scavenged[i]|m.pallocBits[i], uint(min))
-	z1 := uint(sys.LeadingZeros64(^x))
-	run, end := uint(0), uint(i)*64+(64-z1)
-	if x<<z1 != 0 {
-		// After shifting out z1 bits, we still have 1s,
-		// so the run ends inside this word.
-		run = uint(sys.LeadingZeros64(x << z1))
-	} else {
-		// After shifting out z1 bits, we have no more 1s.
-		// This means the run extends to the bottom of the
-		// word so it may extend into further words.
-		run = 64 - z1
-		for j := i - 1; j >= 0; j-- {
-			x := fillAligned(m.scavenged[j]|m.pallocBits[j], uint(min))
-			run += uint(sys.LeadingZeros64(x))
-			if x != 0 {
-				// The run stopped in this word.
-				break
-			}
-		}
-	}
-
-	// Split the run we found if it's larger than max but hold on to
-	// our original length, since we may need it later.
-	size := run
-	if size > uint(max) {
-		size = uint(max)
-	}
-	start := end - size
-
-	// Each huge page is guaranteed to fit in a single palloc chunk.
-	//
-	// TODO(mknyszek): Support larger huge page sizes.
-	// TODO(mknyszek): Consider taking pages-per-huge-page as a parameter
-	// so we can write tests for this.
-	if physHugePageSize > pageSize && physHugePageSize > physPageSize {
-		// We have huge pages, so let's ensure we don't break one by scavenging
-		// over a huge page boundary. If the range [start, start+size) overlaps with
-		// a free-and-unscavenged huge page, we want to grow the region we scavenge
-		// to include that huge page.
-
-		// Compute the huge page boundary above our candidate.
-		pagesPerHugePage := uintptr(physHugePageSize / pageSize)
-		hugePageAbove := uint(alignUp(uintptr(start), pagesPerHugePage))
-
-		// If that boundary is within our current candidate, then we may be breaking
-		// a huge page.
-		if hugePageAbove <= end {
-			// Compute the huge page boundary below our candidate.
-			hugePageBelow := uint(alignDown(uintptr(start), pagesPerHugePage))
-
-			if hugePageBelow >= end-run {
-				// We're in danger of breaking apart a huge page since start+size crosses
-				// a huge page boundary and rounding down start to the nearest huge
-				// page boundary is included in the full run we found. Include the entire
-				// huge page in the bound by rounding down to the huge page size.
-				size = size + (start - hugePageBelow)
-				start = hugePageBelow
-			}
-		}
-	}
-	return start, size
-}
diff --git a/contrib/go/_std_1.18/src/runtime/mgcstack.go b/contrib/go/_std_1.18/src/runtime/mgcstack.go
deleted file mode 100644
index 49dc54e165..0000000000
--- a/contrib/go/_std_1.18/src/runtime/mgcstack.go
+++ /dev/null
@@ -1,352 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Garbage collector: stack objects and stack tracing
-// See the design doc at https://docs.google.com/document/d/1un-Jn47yByHL7I0aVIP_uVCMxjdM5mpelJhiKlIqxkE/edit?usp=sharing
-// Also see issue 22350.
-
-// Stack tracing solves the problem of determining which parts of the
-// stack are live and should be scanned. It runs as part of scanning
-// a single goroutine stack.
-//
-// Normally determining which parts of the stack are live is easy to
-// do statically, as user code has explicit references (reads and
-// writes) to stack variables. The compiler can do a simple dataflow
-// analysis to determine liveness of stack variables at every point in
-// the code. See cmd/compile/internal/gc/plive.go for that analysis.
-//
-// However, when we take the address of a stack variable, determining
-// whether that variable is still live is less clear. We can still
-// look for static accesses, but accesses through a pointer to the
-// variable are difficult in general to track statically. That pointer
-// can be passed among functions on the stack, conditionally retained,
-// etc.
-//
-// Instead, we will track pointers to stack variables dynamically.
-// All pointers to stack-allocated variables will themselves be on the
-// stack somewhere (or in associated locations, like defer records), so
-// we can find them all efficiently.
-//
-// Stack tracing is organized as a mini garbage collection tracing
-// pass. The objects in this garbage collection are all the variables
-// on the stack whose address is taken, and which themselves contain a
-// pointer. We call these variables "stack objects".
-//
-// We begin by determining all the stack objects on the stack and all
-// the statically live pointers that may point into the stack. We then
-// process each pointer to see if it points to a stack object. If it
-// does, we scan that stack object. It may contain pointers into the
-// heap, in which case those pointers are passed to the main garbage
-// collection. It may also contain pointers into the stack, in which
-// case we add them to our set of stack pointers.
-//
-// Once we're done processing all the pointers (including the ones we
-// added during processing), we've found all the stack objects that
-// are live. Any dead stack objects are not scanned and their contents
-// will not keep heap objects live. Unlike the main garbage
-// collection, we can't sweep the dead stack objects; they live on in
-// a moribund state until the stack frame that contains them is
-// popped.
-//
-// A stack can look like this:
-//
-// +----------+
-// | foo()    |
-// | +------+ |
-// | |  A   | | <---\
-// | +------+ |     |
-// |          |     |
-// | +------+ |     |
-// | |  B   | |     |
-// | +------+ |     |
-// |          |     |
-// +----------+     |
-// | bar()    |     |
-// | +------+ |     |
-// | |  C   | | <-\ |
-// | +----|-+ |   | |
-// |      |   |   | |
-// | +----v-+ |   | |
-// | |  D  ---------/
-// | +------+ |   |
-// |          |   |
-// +----------+   |
-// | baz()    |   |
-// | +------+ |   |
-// | |  E  -------/
-// | +------+ |
-// |      ^   |
-// | F: --/   |
-// |          |
-// +----------+
-//
-// foo() calls bar() calls baz(). Each has a frame on the stack.
-// foo() has stack objects A and B.
-// bar() has stack objects C and D, with C pointing to D and D pointing to A.
-// baz() has a stack object E pointing to C, and a local variable F pointing to E.
-//
-// Starting from the pointer in local variable F, we will eventually
-// scan all of E, C, D, and A (in that order). B is never scanned
-// because there is no live pointer to it. If B is also statically
-// dead (meaning that foo() never accesses B again after it calls
-// bar()), then B's pointers into the heap are not considered live.
-
-package runtime
-
-import (
-	"internal/goarch"
-	"unsafe"
-)
-
-const stackTraceDebug = false
-
-// Buffer for pointers found during stack tracing.
-// Must be smaller than or equal to workbuf.
-//
-//go:notinheap
-type stackWorkBuf struct {
-	stackWorkBufHdr
-	obj [(_WorkbufSize - unsafe.Sizeof(stackWorkBufHdr{})) / goarch.PtrSize]uintptr
-}
-
-// Header declaration must come after the buf declaration above, because of issue #14620.
-//
-//go:notinheap
-type stackWorkBufHdr struct {
-	workbufhdr
-	next *stackWorkBuf // linked list of workbufs
-	// Note: we could theoretically repurpose lfnode.next as this next pointer.
-	// It would save 1 word, but that probably isn't worth busting open
-	// the lfnode API.
-}
-
-// Buffer for stack objects found on a goroutine stack.
-// Must be smaller than or equal to workbuf.
-//
-//go:notinheap
-type stackObjectBuf struct {
-	stackObjectBufHdr
-	obj [(_WorkbufSize - unsafe.Sizeof(stackObjectBufHdr{})) / unsafe.Sizeof(stackObject{})]stackObject
-}
-
-//go:notinheap
-type stackObjectBufHdr struct {
-	workbufhdr
-	next *stackObjectBuf
-}
-
-func init() {
-	if unsafe.Sizeof(stackWorkBuf{}) > unsafe.Sizeof(workbuf{}) {
-		panic("stackWorkBuf too big")
-	}
-	if unsafe.Sizeof(stackObjectBuf{}) > unsafe.Sizeof(workbuf{}) {
-		panic("stackObjectBuf too big")
-	}
-}
-
-// A stackObject represents a variable on the stack that has had
-// its address taken.
-//
-//go:notinheap
-type stackObject struct {
-	off   uint32             // offset above stack.lo
-	size  uint32             // size of object
-	r     *stackObjectRecord // info of the object (for ptr/nonptr bits). nil if object has been scanned.
-	left  *stackObject       // objects with lower addresses
-	right *stackObject       // objects with higher addresses
-}
-
-// obj.r = r, but with no write barrier.
-//go:nowritebarrier
-func (obj *stackObject) setRecord(r *stackObjectRecord) {
-	// Types of stack objects are always in read-only memory, not the heap.
-	// So not using a write barrier is ok.
-	*(*uintptr)(unsafe.Pointer(&obj.r)) = uintptr(unsafe.Pointer(r))
-}
-
-// A stackScanState keeps track of the state used during the GC walk
-// of a goroutine.
-type stackScanState struct {
-	cache pcvalueCache
-
-	// stack limits
-	stack stack
-
-	// conservative indicates that the next frame must be scanned conservatively.
-	// This applies only to the innermost frame at an async safe-point.
-	conservative bool
-
-	// buf contains the set of possible pointers to stack objects.
-	// Organized as a LIFO linked list of buffers.
-	// All buffers except possibly the head buffer are full.
-	buf     *stackWorkBuf
-	freeBuf *stackWorkBuf // keep around one free buffer for allocation hysteresis
-
-	// cbuf contains conservative pointers to stack objects. If
-	// all pointers to a stack object are obtained via
-	// conservative scanning, then the stack object may be dead
-	// and may contain dead pointers, so it must be scanned
-	// defensively.
-	cbuf *stackWorkBuf
-
-	// list of stack objects
-	// Objects are in increasing address order.
-	head  *stackObjectBuf
-	tail  *stackObjectBuf
-	nobjs int
-
-	// root of binary tree for fast object lookup by address
-	// Initialized by buildIndex.
-	root *stackObject
-}
-
-// Add p as a potential pointer to a stack object.
-// p must be a stack address.
-func (s *stackScanState) putPtr(p uintptr, conservative bool) {
-	if p < s.stack.lo || p >= s.stack.hi {
-		throw("address not a stack address")
-	}
-	head := &s.buf
-	if conservative {
-		head = &s.cbuf
-	}
-	buf := *head
-	if buf == nil {
-		// Initial setup.
-		buf = (*stackWorkBuf)(unsafe.Pointer(getempty()))
-		buf.nobj = 0
-		buf.next = nil
-		*head = buf
-	} else if buf.nobj == len(buf.obj) {
-		if s.freeBuf != nil {
-			buf = s.freeBuf
-			s.freeBuf = nil
-		} else {
-			buf = (*stackWorkBuf)(unsafe.Pointer(getempty()))
-		}
-		buf.nobj = 0
-		buf.next = *head
-		*head = buf
-	}
-	buf.obj[buf.nobj] = p
-	buf.nobj++
-}
-
-// Remove and return a potential pointer to a stack object.
-// Returns 0 if there are no more pointers available.
-//
-// This prefers non-conservative pointers so we scan stack objects
-// precisely if there are any non-conservative pointers to them.
-func (s *stackScanState) getPtr() (p uintptr, conservative bool) {
-	for _, head := range []**stackWorkBuf{&s.buf, &s.cbuf} {
-		buf := *head
-		if buf == nil {
-			// Never had any data.
-			continue
-		}
-		if buf.nobj == 0 {
-			if s.freeBuf != nil {
-				// Free old freeBuf.
-				putempty((*workbuf)(unsafe.Pointer(s.freeBuf)))
-			}
-			// Move buf to the freeBuf.
-			s.freeBuf = buf
-			buf = buf.next
-			*head = buf
-			if buf == nil {
-				// No more data in this list.
-				continue
-			}
-		}
-		buf.nobj--
-		return buf.obj[buf.nobj], head == &s.cbuf
-	}
-	// No more data in either list.
-	if s.freeBuf != nil {
-		putempty((*workbuf)(unsafe.Pointer(s.freeBuf)))
-		s.freeBuf = nil
-	}
-	return 0, false
-}
-
-// addObject adds a stack object at addr of type typ to the set of stack objects.
-func (s *stackScanState) addObject(addr uintptr, r *stackObjectRecord) {
-	x := s.tail
-	if x == nil {
-		// initial setup
-		x = (*stackObjectBuf)(unsafe.Pointer(getempty()))
-		x.next = nil
-		s.head = x
-		s.tail = x
-	}
-	if x.nobj > 0 && uint32(addr-s.stack.lo) < x.obj[x.nobj-1].off+x.obj[x.nobj-1].size {
-		throw("objects added out of order or overlapping")
-	}
-	if x.nobj == len(x.obj) {
-		// full buffer - allocate a new buffer, add to end of linked list
-		y := (*stackObjectBuf)(unsafe.Pointer(getempty()))
-		y.next = nil
-		x.next = y
-		s.tail = y
-		x = y
-	}
-	obj := &x.obj[x.nobj]
-	x.nobj++
-	obj.off = uint32(addr - s.stack.lo)
-	obj.size = uint32(r.size)
-	obj.setRecord(r)
-	// obj.left and obj.right will be initialized by buildIndex before use.
-	s.nobjs++
-}
-
-// buildIndex initializes s.root to a binary search tree.
-// It should be called after all addObject calls but before
-// any call of findObject.
-func (s *stackScanState) buildIndex() {
-	s.root, _, _ = binarySearchTree(s.head, 0, s.nobjs)
-}
-
-// Build a binary search tree with the n objects in the list
-// x.obj[idx], x.obj[idx+1], ..., x.next.obj[0], ...
-// Returns the root of that tree, and the buf+idx of the nth object after x.obj[idx].
-// (The first object that was not included in the binary search tree.)
-// If n == 0, returns nil, x.
-func binarySearchTree(x *stackObjectBuf, idx int, n int) (root *stackObject, restBuf *stackObjectBuf, restIdx int) {
-	if n == 0 {
-		return nil, x, idx
-	}
-	var left, right *stackObject
-	left, x, idx = binarySearchTree(x, idx, n/2)
-	root = &x.obj[idx]
-	idx++
-	if idx == len(x.obj) {
-		x = x.next
-		idx = 0
-	}
-	right, x, idx = binarySearchTree(x, idx, n-n/2-1)
-	root.left = left
-	root.right = right
-	return root, x, idx
-}
-
-// findObject returns the stack object containing address a, if any.
-// Must have called buildIndex previously.
-func (s *stackScanState) findObject(a uintptr) *stackObject {
-	off := uint32(a - s.stack.lo)
-	obj := s.root
-	for {
-		if obj == nil {
-			return nil
-		}
-		if off < obj.off {
-			obj = obj.left
-			continue
-		}
-		if off >= obj.off+obj.size {
-			obj = obj.right
-			continue
-		}
-		return obj
-	}
-}
diff --git a/contrib/go/_std_1.18/src/runtime/mgcsweep.go b/contrib/go/_std_1.18/src/runtime/mgcsweep.go
deleted file mode 100644
index 0d58f8e0b5..0000000000
--- a/contrib/go/_std_1.18/src/runtime/mgcsweep.go
+++ /dev/null
@@ -1,878 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Garbage collector: sweeping
-
-// The sweeper consists of two different algorithms:
-//
-// * The object reclaimer finds and frees unmarked slots in spans. It
-//   can free a whole span if none of the objects are marked, but that
-//   isn't its goal. This can be driven either synchronously by
-//   mcentral.cacheSpan for mcentral spans, or asynchronously by
-//   sweepone, which looks at all the mcentral lists.
-//
-// * The span reclaimer looks for spans that contain no marked objects
-//   and frees whole spans. This is a separate algorithm because
-//   freeing whole spans is the hardest task for the object reclaimer,
-//   but is critical when allocating new spans. The entry point for
-//   this is mheap_.reclaim and it's driven by a sequential scan of
-//   the page marks bitmap in the heap arenas.
-//
-// Both algorithms ultimately call mspan.sweep, which sweeps a single
-// heap span.
-
-package runtime
-
-import (
-	"runtime/internal/atomic"
-	"unsafe"
-)
-
-var sweep sweepdata
-
-// State of background sweep.
-type sweepdata struct {
-	lock    mutex
-	g       *g
-	parked  bool
-	started bool
-
-	nbgsweep    uint32
-	npausesweep uint32
-
-	// active tracks outstanding sweepers and the sweep
-	// termination condition.
-	active activeSweep
-
-	// centralIndex is the current unswept span class.
-	// It represents an index into the mcentral span
-	// sets. Accessed and updated via its load and
-	// update methods. Not protected by a lock.
-	//
-	// Reset at mark termination.
-	// Used by mheap.nextSpanForSweep.
-	centralIndex sweepClass
-}
-
-// sweepClass is a spanClass and one bit to represent whether we're currently
-// sweeping partial or full spans.
-type sweepClass uint32
-
-const (
-	numSweepClasses            = numSpanClasses * 2
-	sweepClassDone  sweepClass = sweepClass(^uint32(0))
-)
-
-func (s *sweepClass) load() sweepClass {
-	return sweepClass(atomic.Load((*uint32)(s)))
-}
-
-func (s *sweepClass) update(sNew sweepClass) {
-	// Only update *s if its current value is less than sNew,
-	// since *s increases monotonically.
-	sOld := s.load()
-	for sOld < sNew && !atomic.Cas((*uint32)(s), uint32(sOld), uint32(sNew)) {
-		sOld = s.load()
-	}
-	// TODO(mknyszek): This isn't the only place we have
-	// an atomic monotonically increasing counter. It would
-	// be nice to have an "atomic max" which is just implemented
-	// as the above on most architectures. Some architectures
-	// like RISC-V however have native support for an atomic max.
-}
-
-func (s *sweepClass) clear() {
-	atomic.Store((*uint32)(s), 0)
-}
-
-// split returns the underlying span class as well as
-// whether we're interested in the full or partial
-// unswept lists for that class, indicated as a boolean
-// (true means "full").
-func (s sweepClass) split() (spc spanClass, full bool) {
-	return spanClass(s >> 1), s&1 == 0
-}
-
-// nextSpanForSweep finds and pops the next span for sweeping from the
-// central sweep buffers. It returns ownership of the span to the caller.
-// Returns nil if no such span exists.
-func (h *mheap) nextSpanForSweep() *mspan {
-	sg := h.sweepgen
-	for sc := sweep.centralIndex.load(); sc < numSweepClasses; sc++ {
-		spc, full := sc.split()
-		c := &h.central[spc].mcentral
-		var s *mspan
-		if full {
-			s = c.fullUnswept(sg).pop()
-		} else {
-			s = c.partialUnswept(sg).pop()
-		}
-		if s != nil {
-			// Write down that we found something so future sweepers
-			// can start from here.
-			sweep.centralIndex.update(sc)
-			return s
-		}
-	}
-	// Write down that we found nothing.
-	sweep.centralIndex.update(sweepClassDone)
-	return nil
-}
-
-const sweepDrainedMask = 1 << 31
-
-// activeSweep is a type that captures whether sweeping
-// is done, and whether there are any outstanding sweepers.
-//
-// Every potential sweeper must call begin() before they look
-// for work, and end() after they've finished sweeping.
-type activeSweep struct {
-	// state is divided into two parts.
-	//
-	// The top bit (masked by sweepDrainedMask) is a boolean
-	// value indicating whether all the sweep work has been
-	// drained from the queue.
-	//
-	// The rest of the bits are a counter, indicating the
-	// number of outstanding concurrent sweepers.
-	state atomic.Uint32
-}
-
-// begin registers a new sweeper. Returns a sweepLocker
-// for acquiring spans for sweeping. Any outstanding sweeper blocks
-// sweep termination.
-//
-// If the sweepLocker is invalid, the caller can be sure that all
-// outstanding sweep work has been drained, so there is nothing left
-// to sweep. Note that there may be sweepers currently running, so
-// this does not indicate that all sweeping has completed.
-//
-// Even if the sweepLocker is invalid, its sweepGen is always valid.
-func (a *activeSweep) begin() sweepLocker {
-	for {
-		state := a.state.Load()
-		if state&sweepDrainedMask != 0 {
-			return sweepLocker{mheap_.sweepgen, false}
-		}
-		if a.state.CompareAndSwap(state, state+1) {
-			return sweepLocker{mheap_.sweepgen, true}
-		}
-	}
-}
-
-// end deregisters a sweeper. Must be called once for each time
-// begin is called if the sweepLocker is valid.
-func (a *activeSweep) end(sl sweepLocker) {
-	if sl.sweepGen != mheap_.sweepgen {
-		throw("sweeper left outstanding across sweep generations")
-	}
-	for {
-		state := a.state.Load()
-		if (state&^sweepDrainedMask)-1 >= sweepDrainedMask {
-			throw("mismatched begin/end of activeSweep")
-		}
-		if a.state.CompareAndSwap(state, state-1) {
-			if state != sweepDrainedMask {
-				return
-			}
-			if debug.gcpacertrace > 0 {
-				print("pacer: sweep done at heap size ", gcController.heapLive>>20, "MB; allocated ", (gcController.heapLive-mheap_.sweepHeapLiveBasis)>>20, "MB during sweep; swept ", mheap_.pagesSwept.Load(), " pages at ", mheap_.sweepPagesPerByte, " pages/byte\n")
-			}
-			return
-		}
-	}
-}
-
-// markDrained marks the active sweep cycle as having drained
-// all remaining work. This is safe to be called concurrently
-// with all other methods of activeSweep, though may race.
-//
-// Returns true if this call was the one that actually performed
-// the mark.
-func (a *activeSweep) markDrained() bool {
-	for {
-		state := a.state.Load()
-		if state&sweepDrainedMask != 0 {
-			return false
-		}
-		if a.state.CompareAndSwap(state, state|sweepDrainedMask) {
-			return true
-		}
-	}
-}
-
-// sweepers returns the current number of active sweepers.
-func (a *activeSweep) sweepers() uint32 {
-	return a.state.Load() &^ sweepDrainedMask
-}
-
-// isDone returns true if all sweep work has been drained and no more
-// outstanding sweepers exist. That is, when the sweep phase is
-// completely done.
-func (a *activeSweep) isDone() bool {
-	return a.state.Load() == sweepDrainedMask
-}
-
-// reset sets up the activeSweep for the next sweep cycle.
-//
-// The world must be stopped.
-func (a *activeSweep) reset() {
-	assertWorldStopped()
-	a.state.Store(0)
-}
-
-// finishsweep_m ensures that all spans are swept.
-//
-// The world must be stopped. This ensures there are no sweeps in
-// progress.
-//
-//go:nowritebarrier
-func finishsweep_m() {
-	assertWorldStopped()
-
-	// Sweeping must be complete before marking commences, so
-	// sweep any unswept spans. If this is a concurrent GC, there
-	// shouldn't be any spans left to sweep, so this should finish
-	// instantly. If GC was forced before the concurrent sweep
-	// finished, there may be spans to sweep.
-	for sweepone() != ^uintptr(0) {
-		sweep.npausesweep++
-	}
-
-	// Make sure there aren't any outstanding sweepers left.
-	// At this point, with the world stopped, it means one of two
-	// things. Either we were able to preempt a sweeper, or that
-	// a sweeper didn't call sweep.active.end when it should have.
-	// Both cases indicate a bug, so throw.
-	if sweep.active.sweepers() != 0 {
-		throw("active sweepers found at start of mark phase")
-	}
-
-	// Reset all the unswept buffers, which should be empty.
-	// Do this in sweep termination as opposed to mark termination
-	// so that we can catch unswept spans and reclaim blocks as
-	// soon as possible.
-	sg := mheap_.sweepgen
-	for i := range mheap_.central {
-		c := &mheap_.central[i].mcentral
-		c.partialUnswept(sg).reset()
-		c.fullUnswept(sg).reset()
-	}
-
-	// Sweeping is done, so if the scavenger isn't already awake,
-	// wake it up. There's definitely work for it to do at this
-	// point.
-	wakeScavenger()
-
-	nextMarkBitArenaEpoch()
-}
-
-func bgsweep(c chan int) {
-	sweep.g = getg()
-
-	lockInit(&sweep.lock, lockRankSweep)
-	lock(&sweep.lock)
-	sweep.parked = true
-	c <- 1
-	goparkunlock(&sweep.lock, waitReasonGCSweepWait, traceEvGoBlock, 1)
-
-	for {
-		for sweepone() != ^uintptr(0) {
-			sweep.nbgsweep++
-			Gosched()
-		}
-		for freeSomeWbufs(true) {
-			Gosched()
-		}
-		lock(&sweep.lock)
-		if !isSweepDone() {
-			// This can happen if a GC runs between
-			// gosweepone returning ^0 above
-			// and the lock being acquired.
-			unlock(&sweep.lock)
-			continue
-		}
-		sweep.parked = true
-		goparkunlock(&sweep.lock, waitReasonGCSweepWait, traceEvGoBlock, 1)
-	}
-}
-
-// sweepLocker acquires sweep ownership of spans.
-type sweepLocker struct {
-	// sweepGen is the sweep generation of the heap.
-	sweepGen uint32
-	valid    bool
-}
-
-// sweepLocked represents sweep ownership of a span.
-type sweepLocked struct {
-	*mspan
-}
-
-// tryAcquire attempts to acquire sweep ownership of span s. If it
-// successfully acquires ownership, it blocks sweep completion.
-func (l *sweepLocker) tryAcquire(s *mspan) (sweepLocked, bool) {
-	if !l.valid {
-		throw("use of invalid sweepLocker")
-	}
-	// Check before attempting to CAS.
-	if atomic.Load(&s.sweepgen) != l.sweepGen-2 {
-		return sweepLocked{}, false
-	}
-	// Attempt to acquire sweep ownership of s.
-	if !atomic.Cas(&s.sweepgen, l.sweepGen-2, l.sweepGen-1) {
-		return sweepLocked{}, false
-	}
-	return sweepLocked{s}, true
-}
-
-// sweepone sweeps some unswept heap span and returns the number of pages returned
-// to the heap, or ^uintptr(0) if there was nothing to sweep.
-func sweepone() uintptr {
-	gp := getg()
-
-	// Increment locks to ensure that the goroutine is not preempted
-	// in the middle of sweep thus leaving the span in an inconsistent state for next GC
-	gp.m.locks++
-
-	// TODO(austin): sweepone is almost always called in a loop;
-	// lift the sweepLocker into its callers.
-	sl := sweep.active.begin()
-	if !sl.valid {
-		gp.m.locks--
-		return ^uintptr(0)
-	}
-
-	// Find a span to sweep.
-	npages := ^uintptr(0)
-	var noMoreWork bool
-	for {
-		s := mheap_.nextSpanForSweep()
-		if s == nil {
-			noMoreWork = sweep.active.markDrained()
-			break
-		}
-		if state := s.state.get(); state != mSpanInUse {
-			// This can happen if direct sweeping already
-			// swept this span, but in that case the sweep
-			// generation should always be up-to-date.
-			if !(s.sweepgen == sl.sweepGen || s.sweepgen == sl.sweepGen+3) {
-				print("runtime: bad span s.state=", state, " s.sweepgen=", s.sweepgen, " sweepgen=", sl.sweepGen, "\n")
-				throw("non in-use span in unswept list")
-			}
-			continue
-		}
-		if s, ok := sl.tryAcquire(s); ok {
-			// Sweep the span we found.
-			npages = s.npages
-			if s.sweep(false) {
-				// Whole span was freed. Count it toward the
-				// page reclaimer credit since these pages can
-				// now be used for span allocation.
-				mheap_.reclaimCredit.Add(npages)
-			} else {
-				// Span is still in-use, so this returned no
-				// pages to the heap and the span needs to
-				// move to the swept in-use list.
-				npages = 0
-			}
-			break
-		}
-	}
-	sweep.active.end(sl)
-
-	if noMoreWork {
-		// The sweep list is empty. There may still be
-		// concurrent sweeps running, but we're at least very
-		// close to done sweeping.
-
-		// Move the scavenge gen forward (signalling
-		// that there's new work to do) and wake the scavenger.
-		//
-		// The scavenger is signaled by the last sweeper because once
-		// sweeping is done, we will definitely have useful work for
-		// the scavenger to do, since the scavenger only runs over the
-		// heap once per GC cycle. This update is not done during sweep
-		// termination because in some cases there may be a long delay
-		// between sweep done and sweep termination (e.g. not enough
-		// allocations to trigger a GC) which would be nice to fill in
-		// with scavenging work.
-		systemstack(func() {
-			lock(&mheap_.lock)
-			mheap_.pages.scavengeStartGen()
-			unlock(&mheap_.lock)
-		})
-		// Since we might sweep in an allocation path, it's not possible
-		// for us to wake the scavenger directly via wakeScavenger, since
-		// it could allocate. Ask sysmon to do it for us instead.
-		readyForScavenger()
-	}
-
-	gp.m.locks--
-	return npages
-}
-
-// isSweepDone reports whether all spans are swept.
-//
-// Note that this condition may transition from false to true at any
-// time as the sweeper runs. It may transition from true to false if a
-// GC runs; to prevent that the caller must be non-preemptible or must
-// somehow block GC progress.
-func isSweepDone() bool {
-	return sweep.active.isDone()
-}
-
-// Returns only when span s has been swept.
-//go:nowritebarrier
-func (s *mspan) ensureSwept() {
-	// Caller must disable preemption.
-	// Otherwise when this function returns the span can become unswept again
-	// (if GC is triggered on another goroutine).
-	_g_ := getg()
-	if _g_.m.locks == 0 && _g_.m.mallocing == 0 && _g_ != _g_.m.g0 {
-		throw("mspan.ensureSwept: m is not locked")
-	}
-
-	// If this operation fails, then that means that there are
-	// no more spans to be swept. In this case, either s has already
-	// been swept, or is about to be acquired for sweeping and swept.
-	sl := sweep.active.begin()
-	if sl.valid {
-		// The caller must be sure that the span is a mSpanInUse span.
-		if s, ok := sl.tryAcquire(s); ok {
-			s.sweep(false)
-			sweep.active.end(sl)
-			return
-		}
-		sweep.active.end(sl)
-	}
-
-	// Unfortunately we can't sweep the span ourselves. Somebody else
-	// got to it first. We don't have efficient means to wait, but that's
-	// OK, it will be swept fairly soon.
-	for {
-		spangen := atomic.Load(&s.sweepgen)
-		if spangen == sl.sweepGen || spangen == sl.sweepGen+3 {
-			break
-		}
-		osyield()
-	}
-}
-
-// Sweep frees or collects finalizers for blocks not marked in the mark phase.
-// It clears the mark bits in preparation for the next GC round.
-// Returns true if the span was returned to heap.
-// If preserve=true, don't return it to heap nor relink in mcentral lists;
-// caller takes care of it.
-func (sl *sweepLocked) sweep(preserve bool) bool {
-	// It's critical that we enter this function with preemption disabled,
-	// GC must not start while we are in the middle of this function.
-	_g_ := getg()
-	if _g_.m.locks == 0 && _g_.m.mallocing == 0 && _g_ != _g_.m.g0 {
-		throw("mspan.sweep: m is not locked")
-	}
-
-	s := sl.mspan
-	if !preserve {
-		// We'll release ownership of this span. Nil it out to
-		// prevent the caller from accidentally using it.
-		sl.mspan = nil
-	}
-
-	sweepgen := mheap_.sweepgen
-	if state := s.state.get(); state != mSpanInUse || s.sweepgen != sweepgen-1 {
-		print("mspan.sweep: state=", state, " sweepgen=", s.sweepgen, " mheap.sweepgen=", sweepgen, "\n")
-		throw("mspan.sweep: bad span state")
-	}
-
-	if trace.enabled {
-		traceGCSweepSpan(s.npages * _PageSize)
-	}
-
-	mheap_.pagesSwept.Add(int64(s.npages))
-
-	spc := s.spanclass
-	size := s.elemsize
-
-	// The allocBits indicate which unmarked objects don't need to be
-	// processed since they were free at the end of the last GC cycle
-	// and were not allocated since then.
-	// If the allocBits index is >= s.freeindex and the bit
-	// is not marked then the object remains unallocated
-	// since the last GC.
-	// This situation is analogous to being on a freelist.
-
-	// Unlink & free special records for any objects we're about to free.
-	// Two complications here:
-	// 1. An object can have both finalizer and profile special records.
-	//    In such case we need to queue finalizer for execution,
-	//    mark the object as live and preserve the profile special.
-	// 2. A tiny object can have several finalizers setup for different offsets.
-	//    If such object is not marked, we need to queue all finalizers at once.
-	// Both 1 and 2 are possible at the same time.
-	hadSpecials := s.specials != nil
-	siter := newSpecialsIter(s)
-	for siter.valid() {
-		// A finalizer can be set for an inner byte of an object, find object beginning.
-		objIndex := uintptr(siter.s.offset) / size
-		p := s.base() + objIndex*size
-		mbits := s.markBitsForIndex(objIndex)
-		if !mbits.isMarked() {
-			// This object is not marked and has at least one special record.
-			// Pass 1: see if it has at least one finalizer.
-			hasFin := false
-			endOffset := p - s.base() + size
-			for tmp := siter.s; tmp != nil && uintptr(tmp.offset) < endOffset; tmp = tmp.next {
-				if tmp.kind == _KindSpecialFinalizer {
-					// Stop freeing of object if it has a finalizer.
-					mbits.setMarkedNonAtomic()
-					hasFin = true
-					break
-				}
-			}
-			// Pass 2: queue all finalizers _or_ handle profile record.
-			for siter.valid() && uintptr(siter.s.offset) < endOffset {
-				// Find the exact byte for which the special was setup
-				// (as opposed to object beginning).
-				special := siter.s
-				p := s.base() + uintptr(special.offset)
-				if special.kind == _KindSpecialFinalizer || !hasFin {
-					siter.unlinkAndNext()
-					freeSpecial(special, unsafe.Pointer(p), size)
-				} else {
-					// The object has finalizers, so we're keeping it alive.
-					// All other specials only apply when an object is freed,
-					// so just keep the special record.
-					siter.next()
-				}
-			}
-		} else {
-			// object is still live
-			if siter.s.kind == _KindSpecialReachable {
-				special := siter.unlinkAndNext()
-				(*specialReachable)(unsafe.Pointer(special)).reachable = true
-				freeSpecial(special, unsafe.Pointer(p), size)
-			} else {
-				// keep special record
-				siter.next()
-			}
-		}
-	}
-	if hadSpecials && s.specials == nil {
-		spanHasNoSpecials(s)
-	}
-
-	if debug.allocfreetrace != 0 || debug.clobberfree != 0 || raceenabled || msanenabled || asanenabled {
-		// Find all newly freed objects. This doesn't have to
-		// efficient; allocfreetrace has massive overhead.
-		mbits := s.markBitsForBase()
-		abits := s.allocBitsForIndex(0)
-		for i := uintptr(0); i < s.nelems; i++ {
-			if !mbits.isMarked() && (abits.index < s.freeindex || abits.isMarked()) {
-				x := s.base() + i*s.elemsize
-				if debug.allocfreetrace != 0 {
-					tracefree(unsafe.Pointer(x), size)
-				}
-				if debug.clobberfree != 0 {
-					clobberfree(unsafe.Pointer(x), size)
-				}
-				if raceenabled {
-					racefree(unsafe.Pointer(x), size)
-				}
-				if msanenabled {
-					msanfree(unsafe.Pointer(x), size)
-				}
-				if asanenabled {
-					asanpoison(unsafe.Pointer(x), size)
-				}
-			}
-			mbits.advance()
-			abits.advance()
-		}
-	}
-
-	// Check for zombie objects.
-	if s.freeindex < s.nelems {
-		// Everything < freeindex is allocated and hence
-		// cannot be zombies.
-		//
-		// Check the first bitmap byte, where we have to be
-		// careful with freeindex.
-		obj := s.freeindex
-		if (*s.gcmarkBits.bytep(obj / 8)&^*s.allocBits.bytep(obj / 8))>>(obj%8) != 0 {
-			s.reportZombies()
-		}
-		// Check remaining bytes.
-		for i := obj/8 + 1; i < divRoundUp(s.nelems, 8); i++ {
-			if *s.gcmarkBits.bytep(i)&^*s.allocBits.bytep(i) != 0 {
-				s.reportZombies()
-			}
-		}
-	}
-
-	// Count the number of free objects in this span.
-	nalloc := uint16(s.countAlloc())
-	nfreed := s.allocCount - nalloc
-	if nalloc > s.allocCount {
-		// The zombie check above should have caught this in
-		// more detail.
-		print("runtime: nelems=", s.nelems, " nalloc=", nalloc, " previous allocCount=", s.allocCount, " nfreed=", nfreed, "\n")
-		throw("sweep increased allocation count")
-	}
-
-	s.allocCount = nalloc
-	s.freeindex = 0 // reset allocation index to start of span.
-	if trace.enabled {
-		getg().m.p.ptr().traceReclaimed += uintptr(nfreed) * s.elemsize
-	}
-
-	// gcmarkBits becomes the allocBits.
-	// get a fresh cleared gcmarkBits in preparation for next GC
-	s.allocBits = s.gcmarkBits
-	s.gcmarkBits = newMarkBits(s.nelems)
-
-	// Initialize alloc bits cache.
-	s.refillAllocCache(0)
-
-	// The span must be in our exclusive ownership until we update sweepgen,
-	// check for potential races.
-	if state := s.state.get(); state != mSpanInUse || s.sweepgen != sweepgen-1 {
-		print("mspan.sweep: state=", state, " sweepgen=", s.sweepgen, " mheap.sweepgen=", sweepgen, "\n")
-		throw("mspan.sweep: bad span state after sweep")
-	}
-	if s.sweepgen == sweepgen+1 || s.sweepgen == sweepgen+3 {
-		throw("swept cached span")
-	}
-
-	// We need to set s.sweepgen = h.sweepgen only when all blocks are swept,
-	// because of the potential for a concurrent free/SetFinalizer.
-	//
-	// But we need to set it before we make the span available for allocation
-	// (return it to heap or mcentral), because allocation code assumes that a
-	// span is already swept if available for allocation.
-	//
-	// Serialization point.
-	// At this point the mark bits are cleared and allocation ready
-	// to go so release the span.
-	atomic.Store(&s.sweepgen, sweepgen)
-
-	if spc.sizeclass() != 0 {
-		// Handle spans for small objects.
-		if nfreed > 0 {
-			// Only mark the span as needing zeroing if we've freed any
-			// objects, because a fresh span that had been allocated into,
-			// wasn't totally filled, but then swept, still has all of its
-			// free slots zeroed.
-			s.needzero = 1
-			stats := memstats.heapStats.acquire()
-			atomic.Xadd64(&stats.smallFreeCount[spc.sizeclass()], int64(nfreed))
-			memstats.heapStats.release()
-		}
-		if !preserve {
-			// The caller may not have removed this span from whatever
-			// unswept set its on but taken ownership of the span for
-			// sweeping by updating sweepgen. If this span still is in
-			// an unswept set, then the mcentral will pop it off the
-			// set, check its sweepgen, and ignore it.
-			if nalloc == 0 {
-				// Free totally free span directly back to the heap.
-				mheap_.freeSpan(s)
-				return true
-			}
-			// Return span back to the right mcentral list.
-			if uintptr(nalloc) == s.nelems {
-				mheap_.central[spc].mcentral.fullSwept(sweepgen).push(s)
-			} else {
-				mheap_.central[spc].mcentral.partialSwept(sweepgen).push(s)
-			}
-		}
-	} else if !preserve {
-		// Handle spans for large objects.
-		if nfreed != 0 {
-			// Free large object span to heap.
-
-			// NOTE(rsc,dvyukov): The original implementation of efence
-			// in CL 22060046 used sysFree instead of sysFault, so that
-			// the operating system would eventually give the memory
-			// back to us again, so that an efence program could run
-			// longer without running out of memory. Unfortunately,
-			// calling sysFree here without any kind of adjustment of the
-			// heap data structures means that when the memory does
-			// come back to us, we have the wrong metadata for it, either in
-			// the mspan structures or in the garbage collection bitmap.
-			// Using sysFault here means that the program will run out of
-			// memory fairly quickly in efence mode, but at least it won't
-			// have mysterious crashes due to confused memory reuse.
-			// It should be possible to switch back to sysFree if we also
-			// implement and then call some kind of mheap.deleteSpan.
-			if debug.efence > 0 {
-				s.limit = 0 // prevent mlookup from finding this span
-				sysFault(unsafe.Pointer(s.base()), size)
-			} else {
-				mheap_.freeSpan(s)
-			}
-			stats := memstats.heapStats.acquire()
-			atomic.Xadd64(&stats.largeFreeCount, 1)
-			atomic.Xadd64(&stats.largeFree, int64(size))
-			memstats.heapStats.release()
-			return true
-		}
-
-		// Add a large span directly onto the full+swept list.
-		mheap_.central[spc].mcentral.fullSwept(sweepgen).push(s)
-	}
-	return false
-}
-
-// reportZombies reports any marked but free objects in s and throws.
-//
-// This generally means one of the following:
-//
-// 1. User code converted a pointer to a uintptr and then back
-// unsafely, and a GC ran while the uintptr was the only reference to
-// an object.
-//
-// 2. User code (or a compiler bug) constructed a bad pointer that
-// points to a free slot, often a past-the-end pointer.
-//
-// 3. The GC two cycles ago missed a pointer and freed a live object,
-// but it was still live in the last cycle, so this GC cycle found a
-// pointer to that object and marked it.
-func (s *mspan) reportZombies() {
-	printlock()
-	print("runtime: marked free object in span ", s, ", elemsize=", s.elemsize, " freeindex=", s.freeindex, " (bad use of unsafe.Pointer? try -d=checkptr)\n")
-	mbits := s.markBitsForBase()
-	abits := s.allocBitsForIndex(0)
-	for i := uintptr(0); i < s.nelems; i++ {
-		addr := s.base() + i*s.elemsize
-		print(hex(addr))
-		alloc := i < s.freeindex || abits.isMarked()
-		if alloc {
-			print(" alloc")
-		} else {
-			print(" free ")
-		}
-		if mbits.isMarked() {
-			print(" marked  ")
-		} else {
-			print(" unmarked")
-		}
-		zombie := mbits.isMarked() && !alloc
-		if zombie {
-			print(" zombie")
-		}
-		print("\n")
-		if zombie {
-			length := s.elemsize
-			if length > 1024 {
-				length = 1024
-			}
-			hexdumpWords(addr, addr+length, nil)
-		}
-		mbits.advance()
-		abits.advance()
-	}
-	throw("found pointer to free object")
-}
-
-// deductSweepCredit deducts sweep credit for allocating a span of
-// size spanBytes. This must be performed *before* the span is
-// allocated to ensure the system has enough credit. If necessary, it
-// performs sweeping to prevent going in to debt. If the caller will
-// also sweep pages (e.g., for a large allocation), it can pass a
-// non-zero callerSweepPages to leave that many pages unswept.
-//
-// deductSweepCredit makes a worst-case assumption that all spanBytes
-// bytes of the ultimately allocated span will be available for object
-// allocation.
-//
-// deductSweepCredit is the core of the "proportional sweep" system.
-// It uses statistics gathered by the garbage collector to perform
-// enough sweeping so that all pages are swept during the concurrent
-// sweep phase between GC cycles.
-//
-// mheap_ must NOT be locked.
-func deductSweepCredit(spanBytes uintptr, callerSweepPages uintptr) {
-	if mheap_.sweepPagesPerByte == 0 {
-		// Proportional sweep is done or disabled.
-		return
-	}
-
-	if trace.enabled {
-		traceGCSweepStart()
-	}
-
-retry:
-	sweptBasis := mheap_.pagesSweptBasis.Load()
-
-	// Fix debt if necessary.
-	newHeapLive := uintptr(atomic.Load64(&gcController.heapLive)-mheap_.sweepHeapLiveBasis) + spanBytes
-	pagesTarget := int64(mheap_.sweepPagesPerByte*float64(newHeapLive)) - int64(callerSweepPages)
-	for pagesTarget > int64(mheap_.pagesSwept.Load()-sweptBasis) {
-		if sweepone() == ^uintptr(0) {
-			mheap_.sweepPagesPerByte = 0
-			break
-		}
-		if mheap_.pagesSweptBasis.Load() != sweptBasis {
-			// Sweep pacing changed. Recompute debt.
-			goto retry
-		}
-	}
-
-	if trace.enabled {
-		traceGCSweepDone()
-	}
-}
-
-// clobberfree sets the memory content at x to bad content, for debugging
-// purposes.
-func clobberfree(x unsafe.Pointer, size uintptr) {
-	// size (span.elemsize) is always a multiple of 4.
-	for i := uintptr(0); i < size; i += 4 {
-		*(*uint32)(add(x, i)) = 0xdeadbeef
-	}
-}
-
-// gcPaceSweeper updates the sweeper's pacing parameters.
-//
-// Must be called whenever the GC's pacing is updated.
-//
-// The world must be stopped, or mheap_.lock must be held.
-func gcPaceSweeper(trigger uint64) {
-	assertWorldStoppedOrLockHeld(&mheap_.lock)
-
-	// Update sweep pacing.
-	if isSweepDone() {
-		mheap_.sweepPagesPerByte = 0
-	} else {
-		// Concurrent sweep needs to sweep all of the in-use
-		// pages by the time the allocated heap reaches the GC
-		// trigger. Compute the ratio of in-use pages to sweep
-		// per byte allocated, accounting for the fact that
-		// some might already be swept.
-		heapLiveBasis := atomic.Load64(&gcController.heapLive)
-		heapDistance := int64(trigger) - int64(heapLiveBasis)
-		// Add a little margin so rounding errors and
-		// concurrent sweep are less likely to leave pages
-		// unswept when GC starts.
-		heapDistance -= 1024 * 1024
-		if heapDistance < _PageSize {
-			// Avoid setting the sweep ratio extremely high
-			heapDistance = _PageSize
-		}
-		pagesSwept := mheap_.pagesSwept.Load()
-		pagesInUse := mheap_.pagesInUse.Load()
-		sweepDistancePages := int64(pagesInUse) - int64(pagesSwept)
-		if sweepDistancePages <= 0 {
-			mheap_.sweepPagesPerByte = 0
-		} else {
-			mheap_.sweepPagesPerByte = float64(sweepDistancePages) / float64(heapDistance)
-			mheap_.sweepHeapLiveBasis = heapLiveBasis
-			// Write pagesSweptBasis last, since this
-			// signals concurrent sweeps to recompute
-			// their debt.
-			mheap_.pagesSweptBasis.Store(pagesSwept)
-		}
-	}
-}
diff --git a/contrib/go/_std_1.18/src/runtime/mgcwork.go b/contrib/go/_std_1.18/src/runtime/mgcwork.go
deleted file mode 100644
index 9c3f7fd223..0000000000
--- a/contrib/go/_std_1.18/src/runtime/mgcwork.go
+++ /dev/null
@@ -1,483 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"internal/goarch"
-	"runtime/internal/atomic"
-	"unsafe"
-)
-
-const (
-	_WorkbufSize = 2048 // in bytes; larger values result in less contention
-
-	// workbufAlloc is the number of bytes to allocate at a time
-	// for new workbufs. This must be a multiple of pageSize and
-	// should be a multiple of _WorkbufSize.
-	//
-	// Larger values reduce workbuf allocation overhead. Smaller
-	// values reduce heap fragmentation.
-	workbufAlloc = 32 << 10
-)
-
-func init() {
-	if workbufAlloc%pageSize != 0 || workbufAlloc%_WorkbufSize != 0 {
-		throw("bad workbufAlloc")
-	}
-}
-
-// Garbage collector work pool abstraction.
-//
-// This implements a producer/consumer model for pointers to grey
-// objects. A grey object is one that is marked and on a work
-// queue. A black object is marked and not on a work queue.
-//
-// Write barriers, root discovery, stack scanning, and object scanning
-// produce pointers to grey objects. Scanning consumes pointers to
-// grey objects, thus blackening them, and then scans them,
-// potentially producing new pointers to grey objects.
-
-// A gcWork provides the interface to produce and consume work for the
-// garbage collector.
-//
-// A gcWork can be used on the stack as follows:
-//
-//     (preemption must be disabled)
-//     gcw := &getg().m.p.ptr().gcw
-//     .. call gcw.put() to produce and gcw.tryGet() to consume ..
-//
-// It's important that any use of gcWork during the mark phase prevent
-// the garbage collector from transitioning to mark termination since
-// gcWork may locally hold GC work buffers. This can be done by
-// disabling preemption (systemstack or acquirem).
-type gcWork struct {
-	// wbuf1 and wbuf2 are the primary and secondary work buffers.
-	//
-	// This can be thought of as a stack of both work buffers'
-	// pointers concatenated. When we pop the last pointer, we
-	// shift the stack up by one work buffer by bringing in a new
-	// full buffer and discarding an empty one. When we fill both
-	// buffers, we shift the stack down by one work buffer by
-	// bringing in a new empty buffer and discarding a full one.
-	// This way we have one buffer's worth of hysteresis, which
-	// amortizes the cost of getting or putting a work buffer over
-	// at least one buffer of work and reduces contention on the
-	// global work lists.
-	//
-	// wbuf1 is always the buffer we're currently pushing to and
-	// popping from and wbuf2 is the buffer that will be discarded
-	// next.
-	//
-	// Invariant: Both wbuf1 and wbuf2 are nil or neither are.
-	wbuf1, wbuf2 *workbuf
-
-	// Bytes marked (blackened) on this gcWork. This is aggregated
-	// into work.bytesMarked by dispose.
-	bytesMarked uint64
-
-	// Heap scan work performed on this gcWork. This is aggregated into
-	// gcController by dispose and may also be flushed by callers.
-	// Other types of scan work are flushed immediately.
-	heapScanWork int64
-
-	// flushedWork indicates that a non-empty work buffer was
-	// flushed to the global work list since the last gcMarkDone
-	// termination check. Specifically, this indicates that this
-	// gcWork may have communicated work to another gcWork.
-	flushedWork bool
-}
-
-// Most of the methods of gcWork are go:nowritebarrierrec because the
-// write barrier itself can invoke gcWork methods but the methods are
-// not generally re-entrant. Hence, if a gcWork method invoked the
-// write barrier while the gcWork was in an inconsistent state, and
-// the write barrier in turn invoked a gcWork method, it could
-// permanently corrupt the gcWork.
-
-func (w *gcWork) init() {
-	w.wbuf1 = getempty()
-	wbuf2 := trygetfull()
-	if wbuf2 == nil {
-		wbuf2 = getempty()
-	}
-	w.wbuf2 = wbuf2
-}
-
-// put enqueues a pointer for the garbage collector to trace.
-// obj must point to the beginning of a heap object or an oblet.
-//go:nowritebarrierrec
-func (w *gcWork) put(obj uintptr) {
-	flushed := false
-	wbuf := w.wbuf1
-	// Record that this may acquire the wbufSpans or heap lock to
-	// allocate a workbuf.
-	lockWithRankMayAcquire(&work.wbufSpans.lock, lockRankWbufSpans)
-	lockWithRankMayAcquire(&mheap_.lock, lockRankMheap)
-	if wbuf == nil {
-		w.init()
-		wbuf = w.wbuf1
-		// wbuf is empty at this point.
-	} else if wbuf.nobj == len(wbuf.obj) {
-		w.wbuf1, w.wbuf2 = w.wbuf2, w.wbuf1
-		wbuf = w.wbuf1
-		if wbuf.nobj == len(wbuf.obj) {
-			putfull(wbuf)
-			w.flushedWork = true
-			wbuf = getempty()
-			w.wbuf1 = wbuf
-			flushed = true
-		}
-	}
-
-	wbuf.obj[wbuf.nobj] = obj
-	wbuf.nobj++
-
-	// If we put a buffer on full, let the GC controller know so
-	// it can encourage more workers to run. We delay this until
-	// the end of put so that w is in a consistent state, since
-	// enlistWorker may itself manipulate w.
-	if flushed && gcphase == _GCmark {
-		gcController.enlistWorker()
-	}
-}
-
-// putFast does a put and reports whether it can be done quickly
-// otherwise it returns false and the caller needs to call put.
-//go:nowritebarrierrec
-func (w *gcWork) putFast(obj uintptr) bool {
-	wbuf := w.wbuf1
-	if wbuf == nil {
-		return false
-	} else if wbuf.nobj == len(wbuf.obj) {
-		return false
-	}
-
-	wbuf.obj[wbuf.nobj] = obj
-	wbuf.nobj++
-	return true
-}
-
-// putBatch performs a put on every pointer in obj. See put for
-// constraints on these pointers.
-//
-//go:nowritebarrierrec
-func (w *gcWork) putBatch(obj []uintptr) {
-	if len(obj) == 0 {
-		return
-	}
-
-	flushed := false
-	wbuf := w.wbuf1
-	if wbuf == nil {
-		w.init()
-		wbuf = w.wbuf1
-	}
-
-	for len(obj) > 0 {
-		for wbuf.nobj == len(wbuf.obj) {
-			putfull(wbuf)
-			w.flushedWork = true
-			w.wbuf1, w.wbuf2 = w.wbuf2, getempty()
-			wbuf = w.wbuf1
-			flushed = true
-		}
-		n := copy(wbuf.obj[wbuf.nobj:], obj)
-		wbuf.nobj += n
-		obj = obj[n:]
-	}
-
-	if flushed && gcphase == _GCmark {
-		gcController.enlistWorker()
-	}
-}
-
-// tryGet dequeues a pointer for the garbage collector to trace.
-//
-// If there are no pointers remaining in this gcWork or in the global
-// queue, tryGet returns 0.  Note that there may still be pointers in
-// other gcWork instances or other caches.
-//go:nowritebarrierrec
-func (w *gcWork) tryGet() uintptr {
-	wbuf := w.wbuf1
-	if wbuf == nil {
-		w.init()
-		wbuf = w.wbuf1
-		// wbuf is empty at this point.
-	}
-	if wbuf.nobj == 0 {
-		w.wbuf1, w.wbuf2 = w.wbuf2, w.wbuf1
-		wbuf = w.wbuf1
-		if wbuf.nobj == 0 {
-			owbuf := wbuf
-			wbuf = trygetfull()
-			if wbuf == nil {
-				return 0
-			}
-			putempty(owbuf)
-			w.wbuf1 = wbuf
-		}
-	}
-
-	wbuf.nobj--
-	return wbuf.obj[wbuf.nobj]
-}
-
-// tryGetFast dequeues a pointer for the garbage collector to trace
-// if one is readily available. Otherwise it returns 0 and
-// the caller is expected to call tryGet().
-//go:nowritebarrierrec
-func (w *gcWork) tryGetFast() uintptr {
-	wbuf := w.wbuf1
-	if wbuf == nil {
-		return 0
-	}
-	if wbuf.nobj == 0 {
-		return 0
-	}
-
-	wbuf.nobj--
-	return wbuf.obj[wbuf.nobj]
-}
-
-// dispose returns any cached pointers to the global queue.
-// The buffers are being put on the full queue so that the
-// write barriers will not simply reacquire them before the
-// GC can inspect them. This helps reduce the mutator's
-// ability to hide pointers during the concurrent mark phase.
-//
-//go:nowritebarrierrec
-func (w *gcWork) dispose() {
-	if wbuf := w.wbuf1; wbuf != nil {
-		if wbuf.nobj == 0 {
-			putempty(wbuf)
-		} else {
-			putfull(wbuf)
-			w.flushedWork = true
-		}
-		w.wbuf1 = nil
-
-		wbuf = w.wbuf2
-		if wbuf.nobj == 0 {
-			putempty(wbuf)
-		} else {
-			putfull(wbuf)
-			w.flushedWork = true
-		}
-		w.wbuf2 = nil
-	}
-	if w.bytesMarked != 0 {
-		// dispose happens relatively infrequently. If this
-		// atomic becomes a problem, we should first try to
-		// dispose less and if necessary aggregate in a per-P
-		// counter.
-		atomic.Xadd64(&work.bytesMarked, int64(w.bytesMarked))
-		w.bytesMarked = 0
-	}
-	if w.heapScanWork != 0 {
-		gcController.heapScanWork.Add(w.heapScanWork)
-		w.heapScanWork = 0
-	}
-}
-
-// balance moves some work that's cached in this gcWork back on the
-// global queue.
-//go:nowritebarrierrec
-func (w *gcWork) balance() {
-	if w.wbuf1 == nil {
-		return
-	}
-	if wbuf := w.wbuf2; wbuf.nobj != 0 {
-		putfull(wbuf)
-		w.flushedWork = true
-		w.wbuf2 = getempty()
-	} else if wbuf := w.wbuf1; wbuf.nobj > 4 {
-		w.wbuf1 = handoff(wbuf)
-		w.flushedWork = true // handoff did putfull
-	} else {
-		return
-	}
-	// We flushed a buffer to the full list, so wake a worker.
-	if gcphase == _GCmark {
-		gcController.enlistWorker()
-	}
-}
-
-// empty reports whether w has no mark work available.
-//go:nowritebarrierrec
-func (w *gcWork) empty() bool {
-	return w.wbuf1 == nil || (w.wbuf1.nobj == 0 && w.wbuf2.nobj == 0)
-}
-
-// Internally, the GC work pool is kept in arrays in work buffers.
-// The gcWork interface caches a work buffer until full (or empty) to
-// avoid contending on the global work buffer lists.
-
-type workbufhdr struct {
-	node lfnode // must be first
-	nobj int
-}
-
-//go:notinheap
-type workbuf struct {
-	workbufhdr
-	// account for the above fields
-	obj [(_WorkbufSize - unsafe.Sizeof(workbufhdr{})) / goarch.PtrSize]uintptr
-}
-
-// workbuf factory routines. These funcs are used to manage the
-// workbufs.
-// If the GC asks for some work these are the only routines that
-// make wbufs available to the GC.
-
-func (b *workbuf) checknonempty() {
-	if b.nobj == 0 {
-		throw("workbuf is empty")
-	}
-}
-
-func (b *workbuf) checkempty() {
-	if b.nobj != 0 {
-		throw("workbuf is not empty")
-	}
-}
-
-// getempty pops an empty work buffer off the work.empty list,
-// allocating new buffers if none are available.
-//go:nowritebarrier
-func getempty() *workbuf {
-	var b *workbuf
-	if work.empty != 0 {
-		b = (*workbuf)(work.empty.pop())
-		if b != nil {
-			b.checkempty()
-		}
-	}
-	// Record that this may acquire the wbufSpans or heap lock to
-	// allocate a workbuf.
-	lockWithRankMayAcquire(&work.wbufSpans.lock, lockRankWbufSpans)
-	lockWithRankMayAcquire(&mheap_.lock, lockRankMheap)
-	if b == nil {
-		// Allocate more workbufs.
-		var s *mspan
-		if work.wbufSpans.free.first != nil {
-			lock(&work.wbufSpans.lock)
-			s = work.wbufSpans.free.first
-			if s != nil {
-				work.wbufSpans.free.remove(s)
-				work.wbufSpans.busy.insert(s)
-			}
-			unlock(&work.wbufSpans.lock)
-		}
-		if s == nil {
-			systemstack(func() {
-				s = mheap_.allocManual(workbufAlloc/pageSize, spanAllocWorkBuf)
-			})
-			if s == nil {
-				throw("out of memory")
-			}
-			// Record the new span in the busy list.
-			lock(&work.wbufSpans.lock)
-			work.wbufSpans.busy.insert(s)
-			unlock(&work.wbufSpans.lock)
-		}
-		// Slice up the span into new workbufs. Return one and
-		// put the rest on the empty list.
-		for i := uintptr(0); i+_WorkbufSize <= workbufAlloc; i += _WorkbufSize {
-			newb := (*workbuf)(unsafe.Pointer(s.base() + i))
-			newb.nobj = 0
-			lfnodeValidate(&newb.node)
-			if i == 0 {
-				b = newb
-			} else {
-				putempty(newb)
-			}
-		}
-	}
-	return b
-}
-
-// putempty puts a workbuf onto the work.empty list.
-// Upon entry this goroutine owns b. The lfstack.push relinquishes ownership.
-//go:nowritebarrier
-func putempty(b *workbuf) {
-	b.checkempty()
-	work.empty.push(&b.node)
-}
-
-// putfull puts the workbuf on the work.full list for the GC.
-// putfull accepts partially full buffers so the GC can avoid competing
-// with the mutators for ownership of partially full buffers.
-//go:nowritebarrier
-func putfull(b *workbuf) {
-	b.checknonempty()
-	work.full.push(&b.node)
-}
-
-// trygetfull tries to get a full or partially empty workbuffer.
-// If one is not immediately available return nil
-//go:nowritebarrier
-func trygetfull() *workbuf {
-	b := (*workbuf)(work.full.pop())
-	if b != nil {
-		b.checknonempty()
-		return b
-	}
-	return b
-}
-
-//go:nowritebarrier
-func handoff(b *workbuf) *workbuf {
-	// Make new buffer with half of b's pointers.
-	b1 := getempty()
-	n := b.nobj / 2
-	b.nobj -= n
-	b1.nobj = n
-	memmove(unsafe.Pointer(&b1.obj[0]), unsafe.Pointer(&b.obj[b.nobj]), uintptr(n)*unsafe.Sizeof(b1.obj[0]))
-
-	// Put b on full list - let first half of b get stolen.
-	putfull(b)
-	return b1
-}
-
-// prepareFreeWorkbufs moves busy workbuf spans to free list so they
-// can be freed to the heap. This must only be called when all
-// workbufs are on the empty list.
-func prepareFreeWorkbufs() {
-	lock(&work.wbufSpans.lock)
-	if work.full != 0 {
-		throw("cannot free workbufs when work.full != 0")
-	}
-	// Since all workbufs are on the empty list, we don't care
-	// which ones are in which spans. We can wipe the entire empty
-	// list and move all workbuf spans to the free list.
-	work.empty = 0
-	work.wbufSpans.free.takeAll(&work.wbufSpans.busy)
-	unlock(&work.wbufSpans.lock)
-}
-
-// freeSomeWbufs frees some workbufs back to the heap and returns
-// true if it should be called again to free more.
-func freeSomeWbufs(preemptible bool) bool {
-	const batchSize = 64 // ~1–2 µs per span.
-	lock(&work.wbufSpans.lock)
-	if gcphase != _GCoff || work.wbufSpans.free.isEmpty() {
-		unlock(&work.wbufSpans.lock)
-		return false
-	}
-	systemstack(func() {
-		gp := getg().m.curg
-		for i := 0; i < batchSize && !(preemptible && gp.preempt); i++ {
-			span := work.wbufSpans.free.first
-			if span == nil {
-				break
-			}
-			work.wbufSpans.free.remove(span)
-			mheap_.freeManual(span, spanAllocWorkBuf)
-		}
-	})
-	more := !work.wbufSpans.free.isEmpty()
-	unlock(&work.wbufSpans.lock)
-	return more
-}
diff --git a/contrib/go/_std_1.18/src/runtime/mheap.go b/contrib/go/_std_1.18/src/runtime/mheap.go
deleted file mode 100644
index ecbd0a3a49..0000000000
--- a/contrib/go/_std_1.18/src/runtime/mheap.go
+++ /dev/null
@@ -1,2119 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Page heap.
-//
-// See malloc.go for overview.
-
-package runtime
-
-import (
-	"internal/cpu"
-	"internal/goarch"
-	"runtime/internal/atomic"
-	"unsafe"
-)
-
-const (
-	// minPhysPageSize is a lower-bound on the physical page size. The
-	// true physical page size may be larger than this. In contrast,
-	// sys.PhysPageSize is an upper-bound on the physical page size.
-	minPhysPageSize = 4096
-
-	// maxPhysPageSize is the maximum page size the runtime supports.
-	maxPhysPageSize = 512 << 10
-
-	// maxPhysHugePageSize sets an upper-bound on the maximum huge page size
-	// that the runtime supports.
-	maxPhysHugePageSize = pallocChunkBytes
-
-	// pagesPerReclaimerChunk indicates how many pages to scan from the
-	// pageInUse bitmap at a time. Used by the page reclaimer.
-	//
-	// Higher values reduce contention on scanning indexes (such as
-	// h.reclaimIndex), but increase the minimum latency of the
-	// operation.
-	//
-	// The time required to scan this many pages can vary a lot depending
-	// on how many spans are actually freed. Experimentally, it can
-	// scan for pages at ~300 GB/ms on a 2.6GHz Core i7, but can only
-	// free spans at ~32 MB/ms. Using 512 pages bounds this at
-	// roughly 100µs.
-	//
-	// Must be a multiple of the pageInUse bitmap element size and
-	// must also evenly divide pagesPerArena.
-	pagesPerReclaimerChunk = 512
-
-	// physPageAlignedStacks indicates whether stack allocations must be
-	// physical page aligned. This is a requirement for MAP_STACK on
-	// OpenBSD.
-	physPageAlignedStacks = GOOS == "openbsd"
-)
-
-// Main malloc heap.
-// The heap itself is the "free" and "scav" treaps,
-// but all the other global data is here too.
-//
-// mheap must not be heap-allocated because it contains mSpanLists,
-// which must not be heap-allocated.
-//
-//go:notinheap
-type mheap struct {
-	// lock must only be acquired on the system stack, otherwise a g
-	// could self-deadlock if its stack grows with the lock held.
-	lock  mutex
-	pages pageAlloc // page allocation data structure
-
-	sweepgen uint32 // sweep generation, see comment in mspan; written during STW
-
-	// allspans is a slice of all mspans ever created. Each mspan
-	// appears exactly once.
-	//
-	// The memory for allspans is manually managed and can be
-	// reallocated and move as the heap grows.
-	//
-	// In general, allspans is protected by mheap_.lock, which
-	// prevents concurrent access as well as freeing the backing
-	// store. Accesses during STW might not hold the lock, but
-	// must ensure that allocation cannot happen around the
-	// access (since that may free the backing store).
-	allspans []*mspan // all spans out there
-
-	// _ uint32 // align uint64 fields on 32-bit for atomics
-
-	// Proportional sweep
-	//
-	// These parameters represent a linear function from gcController.heapLive
-	// to page sweep count. The proportional sweep system works to
-	// stay in the black by keeping the current page sweep count
-	// above this line at the current gcController.heapLive.
-	//
-	// The line has slope sweepPagesPerByte and passes through a
-	// basis point at (sweepHeapLiveBasis, pagesSweptBasis). At
-	// any given time, the system is at (gcController.heapLive,
-	// pagesSwept) in this space.
-	//
-	// It is important that the line pass through a point we
-	// control rather than simply starting at a 0,0 origin
-	// because that lets us adjust sweep pacing at any time while
-	// accounting for current progress. If we could only adjust
-	// the slope, it would create a discontinuity in debt if any
-	// progress has already been made.
-	pagesInUse         atomic.Uint64 // pages of spans in stats mSpanInUse
-	pagesSwept         atomic.Uint64 // pages swept this cycle
-	pagesSweptBasis    atomic.Uint64 // pagesSwept to use as the origin of the sweep ratio
-	sweepHeapLiveBasis uint64        // value of gcController.heapLive to use as the origin of sweep ratio; written with lock, read without
-	sweepPagesPerByte  float64       // proportional sweep ratio; written with lock, read without
-	// TODO(austin): pagesInUse should be a uintptr, but the 386
-	// compiler can't 8-byte align fields.
-
-	// scavengeGoal is the amount of total retained heap memory (measured by
-	// heapRetained) that the runtime will try to maintain by returning memory
-	// to the OS.
-	//
-	// Accessed atomically.
-	scavengeGoal uint64
-
-	// Page reclaimer state
-
-	// reclaimIndex is the page index in allArenas of next page to
-	// reclaim. Specifically, it refers to page (i %
-	// pagesPerArena) of arena allArenas[i / pagesPerArena].
-	//
-	// If this is >= 1<<63, the page reclaimer is done scanning
-	// the page marks.
-	reclaimIndex atomic.Uint64
-
-	// reclaimCredit is spare credit for extra pages swept. Since
-	// the page reclaimer works in large chunks, it may reclaim
-	// more than requested. Any spare pages released go to this
-	// credit pool.
-	reclaimCredit atomic.Uintptr
-
-	// arenas is the heap arena map. It points to the metadata for
-	// the heap for every arena frame of the entire usable virtual
-	// address space.
-	//
-	// Use arenaIndex to compute indexes into this array.
-	//
-	// For regions of the address space that are not backed by the
-	// Go heap, the arena map contains nil.
-	//
-	// Modifications are protected by mheap_.lock. Reads can be
-	// performed without locking; however, a given entry can
-	// transition from nil to non-nil at any time when the lock
-	// isn't held. (Entries never transitions back to nil.)
-	//
-	// In general, this is a two-level mapping consisting of an L1
-	// map and possibly many L2 maps. This saves space when there
-	// are a huge number of arena frames. However, on many
-	// platforms (even 64-bit), arenaL1Bits is 0, making this
-	// effectively a single-level map. In this case, arenas[0]
-	// will never be nil.
-	arenas [1 << arenaL1Bits]*[1 << arenaL2Bits]*heapArena
-
-	// heapArenaAlloc is pre-reserved space for allocating heapArena
-	// objects. This is only used on 32-bit, where we pre-reserve
-	// this space to avoid interleaving it with the heap itself.
-	heapArenaAlloc linearAlloc
-
-	// arenaHints is a list of addresses at which to attempt to
-	// add more heap arenas. This is initially populated with a
-	// set of general hint addresses, and grown with the bounds of
-	// actual heap arena ranges.
-	arenaHints *arenaHint
-
-	// arena is a pre-reserved space for allocating heap arenas
-	// (the actual arenas). This is only used on 32-bit.
-	arena linearAlloc
-
-	// allArenas is the arenaIndex of every mapped arena. This can
-	// be used to iterate through the address space.
-	//
-	// Access is protected by mheap_.lock. However, since this is
-	// append-only and old backing arrays are never freed, it is
-	// safe to acquire mheap_.lock, copy the slice header, and
-	// then release mheap_.lock.
-	allArenas []arenaIdx
-
-	// sweepArenas is a snapshot of allArenas taken at the
-	// beginning of the sweep cycle. This can be read safely by
-	// simply blocking GC (by disabling preemption).
-	sweepArenas []arenaIdx
-
-	// markArenas is a snapshot of allArenas taken at the beginning
-	// of the mark cycle. Because allArenas is append-only, neither
-	// this slice nor its contents will change during the mark, so
-	// it can be read safely.
-	markArenas []arenaIdx
-
-	// curArena is the arena that the heap is currently growing
-	// into. This should always be physPageSize-aligned.
-	curArena struct {
-		base, end uintptr
-	}
-
-	_ uint32 // ensure 64-bit alignment of central
-
-	// central free lists for small size classes.
-	// the padding makes sure that the mcentrals are
-	// spaced CacheLinePadSize bytes apart, so that each mcentral.lock
-	// gets its own cache line.
-	// central is indexed by spanClass.
-	central [numSpanClasses]struct {
-		mcentral mcentral
-		pad      [cpu.CacheLinePadSize - unsafe.Sizeof(mcentral{})%cpu.CacheLinePadSize]byte
-	}
-
-	spanalloc             fixalloc // allocator for span*
-	cachealloc            fixalloc // allocator for mcache*
-	specialfinalizeralloc fixalloc // allocator for specialfinalizer*
-	specialprofilealloc   fixalloc // allocator for specialprofile*
-	specialReachableAlloc fixalloc // allocator for specialReachable
-	speciallock           mutex    // lock for special record allocators.
-	arenaHintAlloc        fixalloc // allocator for arenaHints
-
-	unused *specialfinalizer // never set, just here to force the specialfinalizer type into DWARF
-}
-
-var mheap_ mheap
-
-// A heapArena stores metadata for a heap arena. heapArenas are stored
-// outside of the Go heap and accessed via the mheap_.arenas index.
-//
-//go:notinheap
-type heapArena struct {
-	// bitmap stores the pointer/scalar bitmap for the words in
-	// this arena. See mbitmap.go for a description. Use the
-	// heapBits type to access this.
-	bitmap [heapArenaBitmapBytes]byte
-
-	// spans maps from virtual address page ID within this arena to *mspan.
-	// For allocated spans, their pages map to the span itself.
-	// For free spans, only the lowest and highest pages map to the span itself.
-	// Internal pages map to an arbitrary span.
-	// For pages that have never been allocated, spans entries are nil.
-	//
-	// Modifications are protected by mheap.lock. Reads can be
-	// performed without locking, but ONLY from indexes that are
-	// known to contain in-use or stack spans. This means there
-	// must not be a safe-point between establishing that an
-	// address is live and looking it up in the spans array.
-	spans [pagesPerArena]*mspan
-
-	// pageInUse is a bitmap that indicates which spans are in
-	// state mSpanInUse. This bitmap is indexed by page number,
-	// but only the bit corresponding to the first page in each
-	// span is used.
-	//
-	// Reads and writes are atomic.
-	pageInUse [pagesPerArena / 8]uint8
-
-	// pageMarks is a bitmap that indicates which spans have any
-	// marked objects on them. Like pageInUse, only the bit
-	// corresponding to the first page in each span is used.
-	//
-	// Writes are done atomically during marking. Reads are
-	// non-atomic and lock-free since they only occur during
-	// sweeping (and hence never race with writes).
-	//
-	// This is used to quickly find whole spans that can be freed.
-	//
-	// TODO(austin): It would be nice if this was uint64 for
-	// faster scanning, but we don't have 64-bit atomic bit
-	// operations.
-	pageMarks [pagesPerArena / 8]uint8
-
-	// pageSpecials is a bitmap that indicates which spans have
-	// specials (finalizers or other). Like pageInUse, only the bit
-	// corresponding to the first page in each span is used.
-	//
-	// Writes are done atomically whenever a special is added to
-	// a span and whenever the last special is removed from a span.
-	// Reads are done atomically to find spans containing specials
-	// during marking.
-	pageSpecials [pagesPerArena / 8]uint8
-
-	// checkmarks stores the debug.gccheckmark state. It is only
-	// used if debug.gccheckmark > 0.
-	checkmarks *checkmarksMap
-
-	// zeroedBase marks the first byte of the first page in this
-	// arena which hasn't been used yet and is therefore already
-	// zero. zeroedBase is relative to the arena base.
-	// Increases monotonically until it hits heapArenaBytes.
-	//
-	// This field is sufficient to determine if an allocation
-	// needs to be zeroed because the page allocator follows an
-	// address-ordered first-fit policy.
-	//
-	// Read atomically and written with an atomic CAS.
-	zeroedBase uintptr
-}
-
-// arenaHint is a hint for where to grow the heap arenas. See
-// mheap_.arenaHints.
-//
-//go:notinheap
-type arenaHint struct {
-	addr uintptr
-	down bool
-	next *arenaHint
-}
-
-// An mspan is a run of pages.
-//
-// When a mspan is in the heap free treap, state == mSpanFree
-// and heapmap(s->start) == span, heapmap(s->start+s->npages-1) == span.
-// If the mspan is in the heap scav treap, then in addition to the
-// above scavenged == true. scavenged == false in all other cases.
-//
-// When a mspan is allocated, state == mSpanInUse or mSpanManual
-// and heapmap(i) == span for all s->start <= i < s->start+s->npages.
-
-// Every mspan is in one doubly-linked list, either in the mheap's
-// busy list or one of the mcentral's span lists.
-
-// An mspan representing actual memory has state mSpanInUse,
-// mSpanManual, or mSpanFree. Transitions between these states are
-// constrained as follows:
-//
-// * A span may transition from free to in-use or manual during any GC
-//   phase.
-//
-// * During sweeping (gcphase == _GCoff), a span may transition from
-//   in-use to free (as a result of sweeping) or manual to free (as a
-//   result of stacks being freed).
-//
-// * During GC (gcphase != _GCoff), a span *must not* transition from
-//   manual or in-use to free. Because concurrent GC may read a pointer
-//   and then look up its span, the span state must be monotonic.
-//
-// Setting mspan.state to mSpanInUse or mSpanManual must be done
-// atomically and only after all other span fields are valid.
-// Likewise, if inspecting a span is contingent on it being
-// mSpanInUse, the state should be loaded atomically and checked
-// before depending on other fields. This allows the garbage collector
-// to safely deal with potentially invalid pointers, since resolving
-// such pointers may race with a span being allocated.
-type mSpanState uint8
-
-const (
-	mSpanDead   mSpanState = iota
-	mSpanInUse             // allocated for garbage collected heap
-	mSpanManual            // allocated for manual management (e.g., stack allocator)
-)
-
-// mSpanStateNames are the names of the span states, indexed by
-// mSpanState.
-var mSpanStateNames = []string{
-	"mSpanDead",
-	"mSpanInUse",
-	"mSpanManual",
-	"mSpanFree",
-}
-
-// mSpanStateBox holds an mSpanState and provides atomic operations on
-// it. This is a separate type to disallow accidental comparison or
-// assignment with mSpanState.
-type mSpanStateBox struct {
-	s mSpanState
-}
-
-func (b *mSpanStateBox) set(s mSpanState) {
-	atomic.Store8((*uint8)(&b.s), uint8(s))
-}
-
-func (b *mSpanStateBox) get() mSpanState {
-	return mSpanState(atomic.Load8((*uint8)(&b.s)))
-}
-
-// mSpanList heads a linked list of spans.
-//
-//go:notinheap
-type mSpanList struct {
-	first *mspan // first span in list, or nil if none
-	last  *mspan // last span in list, or nil if none
-}
-
-//go:notinheap
-type mspan struct {
-	next *mspan     // next span in list, or nil if none
-	prev *mspan     // previous span in list, or nil if none
-	list *mSpanList // For debugging. TODO: Remove.
-
-	startAddr uintptr // address of first byte of span aka s.base()
-	npages    uintptr // number of pages in span
-
-	manualFreeList gclinkptr // list of free objects in mSpanManual spans
-
-	// freeindex is the slot index between 0 and nelems at which to begin scanning
-	// for the next free object in this span.
-	// Each allocation scans allocBits starting at freeindex until it encounters a 0
-	// indicating a free object. freeindex is then adjusted so that subsequent scans begin
-	// just past the newly discovered free object.
-	//
-	// If freeindex == nelem, this span has no free objects.
-	//
-	// allocBits is a bitmap of objects in this span.
-	// If n >= freeindex and allocBits[n/8] & (1<<(n%8)) is 0
-	// then object n is free;
-	// otherwise, object n is allocated. Bits starting at nelem are
-	// undefined and should never be referenced.
-	//
-	// Object n starts at address n*elemsize + (start << pageShift).
-	freeindex uintptr
-	// TODO: Look up nelems from sizeclass and remove this field if it
-	// helps performance.
-	nelems uintptr // number of object in the span.
-
-	// Cache of the allocBits at freeindex. allocCache is shifted
-	// such that the lowest bit corresponds to the bit freeindex.
-	// allocCache holds the complement of allocBits, thus allowing
-	// ctz (count trailing zero) to use it directly.
-	// allocCache may contain bits beyond s.nelems; the caller must ignore
-	// these.
-	allocCache uint64
-
-	// allocBits and gcmarkBits hold pointers to a span's mark and
-	// allocation bits. The pointers are 8 byte aligned.
-	// There are three arenas where this data is held.
-	// free: Dirty arenas that are no longer accessed
-	//       and can be reused.
-	// next: Holds information to be used in the next GC cycle.
-	// current: Information being used during this GC cycle.
-	// previous: Information being used during the last GC cycle.
-	// A new GC cycle starts with the call to finishsweep_m.
-	// finishsweep_m moves the previous arena to the free arena,
-	// the current arena to the previous arena, and
-	// the next arena to the current arena.
-	// The next arena is populated as the spans request
-	// memory to hold gcmarkBits for the next GC cycle as well
-	// as allocBits for newly allocated spans.
-	//
-	// The pointer arithmetic is done "by hand" instead of using
-	// arrays to avoid bounds checks along critical performance
-	// paths.
-	// The sweep will free the old allocBits and set allocBits to the
-	// gcmarkBits. The gcmarkBits are replaced with a fresh zeroed
-	// out memory.
-	allocBits  *gcBits
-	gcmarkBits *gcBits
-
-	// sweep generation:
-	// if sweepgen == h->sweepgen - 2, the span needs sweeping
-	// if sweepgen == h->sweepgen - 1, the span is currently being swept
-	// if sweepgen == h->sweepgen, the span is swept and ready to use
-	// if sweepgen == h->sweepgen + 1, the span was cached before sweep began and is still cached, and needs sweeping
-	// if sweepgen == h->sweepgen + 3, the span was swept and then cached and is still cached
-	// h->sweepgen is incremented by 2 after every GC
-
-	sweepgen    uint32
-	divMul      uint32        // for divide by elemsize
-	allocCount  uint16        // number of allocated objects
-	spanclass   spanClass     // size class and noscan (uint8)
-	state       mSpanStateBox // mSpanInUse etc; accessed atomically (get/set methods)
-	needzero    uint8         // needs to be zeroed before allocation
-	elemsize    uintptr       // computed from sizeclass or from npages
-	limit       uintptr       // end of data in span
-	speciallock mutex         // guards specials list
-	specials    *special      // linked list of special records sorted by offset.
-}
-
-func (s *mspan) base() uintptr {
-	return s.startAddr
-}
-
-func (s *mspan) layout() (size, n, total uintptr) {
-	total = s.npages << _PageShift
-	size = s.elemsize
-	if size > 0 {
-		n = total / size
-	}
-	return
-}
-
-// recordspan adds a newly allocated span to h.allspans.
-//
-// This only happens the first time a span is allocated from
-// mheap.spanalloc (it is not called when a span is reused).
-//
-// Write barriers are disallowed here because it can be called from
-// gcWork when allocating new workbufs. However, because it's an
-// indirect call from the fixalloc initializer, the compiler can't see
-// this.
-//
-// The heap lock must be held.
-//
-//go:nowritebarrierrec
-func recordspan(vh unsafe.Pointer, p unsafe.Pointer) {
-	h := (*mheap)(vh)
-	s := (*mspan)(p)
-
-	assertLockHeld(&h.lock)
-
-	if len(h.allspans) >= cap(h.allspans) {
-		n := 64 * 1024 / goarch.PtrSize
-		if n < cap(h.allspans)*3/2 {
-			n = cap(h.allspans) * 3 / 2
-		}
-		var new []*mspan
-		sp := (*slice)(unsafe.Pointer(&new))
-		sp.array = sysAlloc(uintptr(n)*goarch.PtrSize, &memstats.other_sys)
-		if sp.array == nil {
-			throw("runtime: cannot allocate memory")
-		}
-		sp.len = len(h.allspans)
-		sp.cap = n
-		if len(h.allspans) > 0 {
-			copy(new, h.allspans)
-		}
-		oldAllspans := h.allspans
-		*(*notInHeapSlice)(unsafe.Pointer(&h.allspans)) = *(*notInHeapSlice)(unsafe.Pointer(&new))
-		if len(oldAllspans) != 0 {
-			sysFree(unsafe.Pointer(&oldAllspans[0]), uintptr(cap(oldAllspans))*unsafe.Sizeof(oldAllspans[0]), &memstats.other_sys)
-		}
-	}
-	h.allspans = h.allspans[:len(h.allspans)+1]
-	h.allspans[len(h.allspans)-1] = s
-}
-
-// A spanClass represents the size class and noscan-ness of a span.
-//
-// Each size class has a noscan spanClass and a scan spanClass. The
-// noscan spanClass contains only noscan objects, which do not contain
-// pointers and thus do not need to be scanned by the garbage
-// collector.
-type spanClass uint8
-
-const (
-	numSpanClasses = _NumSizeClasses << 1
-	tinySpanClass  = spanClass(tinySizeClass<<1 | 1)
-)
-
-func makeSpanClass(sizeclass uint8, noscan bool) spanClass {
-	return spanClass(sizeclass<<1) | spanClass(bool2int(noscan))
-}
-
-func (sc spanClass) sizeclass() int8 {
-	return int8(sc >> 1)
-}
-
-func (sc spanClass) noscan() bool {
-	return sc&1 != 0
-}
-
-// arenaIndex returns the index into mheap_.arenas of the arena
-// containing metadata for p. This index combines of an index into the
-// L1 map and an index into the L2 map and should be used as
-// mheap_.arenas[ai.l1()][ai.l2()].
-//
-// If p is outside the range of valid heap addresses, either l1() or
-// l2() will be out of bounds.
-//
-// It is nosplit because it's called by spanOf and several other
-// nosplit functions.
-//
-//go:nosplit
-func arenaIndex(p uintptr) arenaIdx {
-	return arenaIdx((p - arenaBaseOffset) / heapArenaBytes)
-}
-
-// arenaBase returns the low address of the region covered by heap
-// arena i.
-func arenaBase(i arenaIdx) uintptr {
-	return uintptr(i)*heapArenaBytes + arenaBaseOffset
-}
-
-type arenaIdx uint
-
-func (i arenaIdx) l1() uint {
-	if arenaL1Bits == 0 {
-		// Let the compiler optimize this away if there's no
-		// L1 map.
-		return 0
-	} else {
-		return uint(i) >> arenaL1Shift
-	}
-}
-
-func (i arenaIdx) l2() uint {
-	if arenaL1Bits == 0 {
-		return uint(i)
-	} else {
-		return uint(i) & (1<<arenaL2Bits - 1)
-	}
-}
-
-// inheap reports whether b is a pointer into a (potentially dead) heap object.
-// It returns false for pointers into mSpanManual spans.
-// Non-preemptible because it is used by write barriers.
-//go:nowritebarrier
-//go:nosplit
-func inheap(b uintptr) bool {
-	return spanOfHeap(b) != nil
-}
-
-// inHeapOrStack is a variant of inheap that returns true for pointers
-// into any allocated heap span.
-//
-//go:nowritebarrier
-//go:nosplit
-func inHeapOrStack(b uintptr) bool {
-	s := spanOf(b)
-	if s == nil || b < s.base() {
-		return false
-	}
-	switch s.state.get() {
-	case mSpanInUse, mSpanManual:
-		return b < s.limit
-	default:
-		return false
-	}
-}
-
-// spanOf returns the span of p. If p does not point into the heap
-// arena or no span has ever contained p, spanOf returns nil.
-//
-// If p does not point to allocated memory, this may return a non-nil
-// span that does *not* contain p. If this is a possibility, the
-// caller should either call spanOfHeap or check the span bounds
-// explicitly.
-//
-// Must be nosplit because it has callers that are nosplit.
-//
-//go:nosplit
-func spanOf(p uintptr) *mspan {
-	// This function looks big, but we use a lot of constant
-	// folding around arenaL1Bits to get it under the inlining
-	// budget. Also, many of the checks here are safety checks
-	// that Go needs to do anyway, so the generated code is quite
-	// short.
-	ri := arenaIndex(p)
-	if arenaL1Bits == 0 {
-		// If there's no L1, then ri.l1() can't be out of bounds but ri.l2() can.
-		if ri.l2() >= uint(len(mheap_.arenas[0])) {
-			return nil
-		}
-	} else {
-		// If there's an L1, then ri.l1() can be out of bounds but ri.l2() can't.
-		if ri.l1() >= uint(len(mheap_.arenas)) {
-			return nil
-		}
-	}
-	l2 := mheap_.arenas[ri.l1()]
-	if arenaL1Bits != 0 && l2 == nil { // Should never happen if there's no L1.
-		return nil
-	}
-	ha := l2[ri.l2()]
-	if ha == nil {
-		return nil
-	}
-	return ha.spans[(p/pageSize)%pagesPerArena]
-}
-
-// spanOfUnchecked is equivalent to spanOf, but the caller must ensure
-// that p points into an allocated heap arena.
-//
-// Must be nosplit because it has callers that are nosplit.
-//
-//go:nosplit
-func spanOfUnchecked(p uintptr) *mspan {
-	ai := arenaIndex(p)
-	return mheap_.arenas[ai.l1()][ai.l2()].spans[(p/pageSize)%pagesPerArena]
-}
-
-// spanOfHeap is like spanOf, but returns nil if p does not point to a
-// heap object.
-//
-// Must be nosplit because it has callers that are nosplit.
-//
-//go:nosplit
-func spanOfHeap(p uintptr) *mspan {
-	s := spanOf(p)
-	// s is nil if it's never been allocated. Otherwise, we check
-	// its state first because we don't trust this pointer, so we
-	// have to synchronize with span initialization. Then, it's
-	// still possible we picked up a stale span pointer, so we
-	// have to check the span's bounds.
-	if s == nil || s.state.get() != mSpanInUse || p < s.base() || p >= s.limit {
-		return nil
-	}
-	return s
-}
-
-// pageIndexOf returns the arena, page index, and page mask for pointer p.
-// The caller must ensure p is in the heap.
-func pageIndexOf(p uintptr) (arena *heapArena, pageIdx uintptr, pageMask uint8) {
-	ai := arenaIndex(p)
-	arena = mheap_.arenas[ai.l1()][ai.l2()]
-	pageIdx = ((p / pageSize) / 8) % uintptr(len(arena.pageInUse))
-	pageMask = byte(1 << ((p / pageSize) % 8))
-	return
-}
-
-// Initialize the heap.
-func (h *mheap) init() {
-	lockInit(&h.lock, lockRankMheap)
-	lockInit(&h.speciallock, lockRankMheapSpecial)
-
-	h.spanalloc.init(unsafe.Sizeof(mspan{}), recordspan, unsafe.Pointer(h), &memstats.mspan_sys)
-	h.cachealloc.init(unsafe.Sizeof(mcache{}), nil, nil, &memstats.mcache_sys)
-	h.specialfinalizeralloc.init(unsafe.Sizeof(specialfinalizer{}), nil, nil, &memstats.other_sys)
-	h.specialprofilealloc.init(unsafe.Sizeof(specialprofile{}), nil, nil, &memstats.other_sys)
-	h.specialReachableAlloc.init(unsafe.Sizeof(specialReachable{}), nil, nil, &memstats.other_sys)
-	h.arenaHintAlloc.init(unsafe.Sizeof(arenaHint{}), nil, nil, &memstats.other_sys)
-
-	// Don't zero mspan allocations. Background sweeping can
-	// inspect a span concurrently with allocating it, so it's
-	// important that the span's sweepgen survive across freeing
-	// and re-allocating a span to prevent background sweeping
-	// from improperly cas'ing it from 0.
-	//
-	// This is safe because mspan contains no heap pointers.
-	h.spanalloc.zero = false
-
-	// h->mapcache needs no init
-
-	for i := range h.central {
-		h.central[i].mcentral.init(spanClass(i))
-	}
-
-	h.pages.init(&h.lock, &memstats.gcMiscSys)
-}
-
-// reclaim sweeps and reclaims at least npage pages into the heap.
-// It is called before allocating npage pages to keep growth in check.
-//
-// reclaim implements the page-reclaimer half of the sweeper.
-//
-// h.lock must NOT be held.
-func (h *mheap) reclaim(npage uintptr) {
-	// TODO(austin): Half of the time spent freeing spans is in
-	// locking/unlocking the heap (even with low contention). We
-	// could make the slow path here several times faster by
-	// batching heap frees.
-
-	// Bail early if there's no more reclaim work.
-	if h.reclaimIndex.Load() >= 1<<63 {
-		return
-	}
-
-	// Disable preemption so the GC can't start while we're
-	// sweeping, so we can read h.sweepArenas, and so
-	// traceGCSweepStart/Done pair on the P.
-	mp := acquirem()
-
-	if trace.enabled {
-		traceGCSweepStart()
-	}
-
-	arenas := h.sweepArenas
-	locked := false
-	for npage > 0 {
-		// Pull from accumulated credit first.
-		if credit := h.reclaimCredit.Load(); credit > 0 {
-			take := credit
-			if take > npage {
-				// Take only what we need.
-				take = npage
-			}
-			if h.reclaimCredit.CompareAndSwap(credit, credit-take) {
-				npage -= take
-			}
-			continue
-		}
-
-		// Claim a chunk of work.
-		idx := uintptr(h.reclaimIndex.Add(pagesPerReclaimerChunk) - pagesPerReclaimerChunk)
-		if idx/pagesPerArena >= uintptr(len(arenas)) {
-			// Page reclaiming is done.
-			h.reclaimIndex.Store(1 << 63)
-			break
-		}
-
-		if !locked {
-			// Lock the heap for reclaimChunk.
-			lock(&h.lock)
-			locked = true
-		}
-
-		// Scan this chunk.
-		nfound := h.reclaimChunk(arenas, idx, pagesPerReclaimerChunk)
-		if nfound <= npage {
-			npage -= nfound
-		} else {
-			// Put spare pages toward global credit.
-			h.reclaimCredit.Add(nfound - npage)
-			npage = 0
-		}
-	}
-	if locked {
-		unlock(&h.lock)
-	}
-
-	if trace.enabled {
-		traceGCSweepDone()
-	}
-	releasem(mp)
-}
-
-// reclaimChunk sweeps unmarked spans that start at page indexes [pageIdx, pageIdx+n).
-// It returns the number of pages returned to the heap.
-//
-// h.lock must be held and the caller must be non-preemptible. Note: h.lock may be
-// temporarily unlocked and re-locked in order to do sweeping or if tracing is
-// enabled.
-func (h *mheap) reclaimChunk(arenas []arenaIdx, pageIdx, n uintptr) uintptr {
-	// The heap lock must be held because this accesses the
-	// heapArena.spans arrays using potentially non-live pointers.
-	// In particular, if a span were freed and merged concurrently
-	// with this probing heapArena.spans, it would be possible to
-	// observe arbitrary, stale span pointers.
-	assertLockHeld(&h.lock)
-
-	n0 := n
-	var nFreed uintptr
-	sl := sweep.active.begin()
-	if !sl.valid {
-		return 0
-	}
-	for n > 0 {
-		ai := arenas[pageIdx/pagesPerArena]
-		ha := h.arenas[ai.l1()][ai.l2()]
-
-		// Get a chunk of the bitmap to work on.
-		arenaPage := uint(pageIdx % pagesPerArena)
-		inUse := ha.pageInUse[arenaPage/8:]
-		marked := ha.pageMarks[arenaPage/8:]
-		if uintptr(len(inUse)) > n/8 {
-			inUse = inUse[:n/8]
-			marked = marked[:n/8]
-		}
-
-		// Scan this bitmap chunk for spans that are in-use
-		// but have no marked objects on them.
-		for i := range inUse {
-			inUseUnmarked := atomic.Load8(&inUse[i]) &^ marked[i]
-			if inUseUnmarked == 0 {
-				continue
-			}
-
-			for j := uint(0); j < 8; j++ {
-				if inUseUnmarked&(1<<j) != 0 {
-					s := ha.spans[arenaPage+uint(i)*8+j]
-					if s, ok := sl.tryAcquire(s); ok {
-						npages := s.npages
-						unlock(&h.lock)
-						if s.sweep(false) {
-							nFreed += npages
-						}
-						lock(&h.lock)
-						// Reload inUse. It's possible nearby
-						// spans were freed when we dropped the
-						// lock and we don't want to get stale
-						// pointers from the spans array.
-						inUseUnmarked = atomic.Load8(&inUse[i]) &^ marked[i]
-					}
-				}
-			}
-		}
-
-		// Advance.
-		pageIdx += uintptr(len(inUse) * 8)
-		n -= uintptr(len(inUse) * 8)
-	}
-	sweep.active.end(sl)
-	if trace.enabled {
-		unlock(&h.lock)
-		// Account for pages scanned but not reclaimed.
-		traceGCSweepSpan((n0 - nFreed) * pageSize)
-		lock(&h.lock)
-	}
-
-	assertLockHeld(&h.lock) // Must be locked on return.
-	return nFreed
-}
-
-// spanAllocType represents the type of allocation to make, or
-// the type of allocation to be freed.
-type spanAllocType uint8
-
-const (
-	spanAllocHeap          spanAllocType = iota // heap span
-	spanAllocStack                              // stack span
-	spanAllocPtrScalarBits                      // unrolled GC prog bitmap span
-	spanAllocWorkBuf                            // work buf span
-)
-
-// manual returns true if the span allocation is manually managed.
-func (s spanAllocType) manual() bool {
-	return s != spanAllocHeap
-}
-
-// alloc allocates a new span of npage pages from the GC'd heap.
-//
-// spanclass indicates the span's size class and scannability.
-//
-// Returns a span that has been fully initialized. span.needzero indicates
-// whether the span has been zeroed. Note that it may not be.
-func (h *mheap) alloc(npages uintptr, spanclass spanClass) *mspan {
-	// Don't do any operations that lock the heap on the G stack.
-	// It might trigger stack growth, and the stack growth code needs
-	// to be able to allocate heap.
-	var s *mspan
-	systemstack(func() {
-		// To prevent excessive heap growth, before allocating n pages
-		// we need to sweep and reclaim at least n pages.
-		if !isSweepDone() {
-			h.reclaim(npages)
-		}
-		s = h.allocSpan(npages, spanAllocHeap, spanclass)
-	})
-	return s
-}
-
-// allocManual allocates a manually-managed span of npage pages.
-// allocManual returns nil if allocation fails.
-//
-// allocManual adds the bytes used to *stat, which should be a
-// memstats in-use field. Unlike allocations in the GC'd heap, the
-// allocation does *not* count toward heap_inuse or heap_sys.
-//
-// The memory backing the returned span may not be zeroed if
-// span.needzero is set.
-//
-// allocManual must be called on the system stack because it may
-// acquire the heap lock via allocSpan. See mheap for details.
-//
-// If new code is written to call allocManual, do NOT use an
-// existing spanAllocType value and instead declare a new one.
-//
-//go:systemstack
-func (h *mheap) allocManual(npages uintptr, typ spanAllocType) *mspan {
-	if !typ.manual() {
-		throw("manual span allocation called with non-manually-managed type")
-	}
-	return h.allocSpan(npages, typ, 0)
-}
-
-// setSpans modifies the span map so [spanOf(base), spanOf(base+npage*pageSize))
-// is s.
-func (h *mheap) setSpans(base, npage uintptr, s *mspan) {
-	p := base / pageSize
-	ai := arenaIndex(base)
-	ha := h.arenas[ai.l1()][ai.l2()]
-	for n := uintptr(0); n < npage; n++ {
-		i := (p + n) % pagesPerArena
-		if i == 0 {
-			ai = arenaIndex(base + n*pageSize)
-			ha = h.arenas[ai.l1()][ai.l2()]
-		}
-		ha.spans[i] = s
-	}
-}
-
-// allocNeedsZero checks if the region of address space [base, base+npage*pageSize),
-// assumed to be allocated, needs to be zeroed, updating heap arena metadata for
-// future allocations.
-//
-// This must be called each time pages are allocated from the heap, even if the page
-// allocator can otherwise prove the memory it's allocating is already zero because
-// they're fresh from the operating system. It updates heapArena metadata that is
-// critical for future page allocations.
-//
-// There are no locking constraints on this method.
-func (h *mheap) allocNeedsZero(base, npage uintptr) (needZero bool) {
-	for npage > 0 {
-		ai := arenaIndex(base)
-		ha := h.arenas[ai.l1()][ai.l2()]
-
-		zeroedBase := atomic.Loaduintptr(&ha.zeroedBase)
-		arenaBase := base % heapArenaBytes
-		if arenaBase < zeroedBase {
-			// We extended into the non-zeroed part of the
-			// arena, so this region needs to be zeroed before use.
-			//
-			// zeroedBase is monotonically increasing, so if we see this now then
-			// we can be sure we need to zero this memory region.
-			//
-			// We still need to update zeroedBase for this arena, and
-			// potentially more arenas.
-			needZero = true
-		}
-		// We may observe arenaBase > zeroedBase if we're racing with one or more
-		// allocations which are acquiring memory directly before us in the address
-		// space. But, because we know no one else is acquiring *this* memory, it's
-		// still safe to not zero.
-
-		// Compute how far into the arena we extend into, capped
-		// at heapArenaBytes.
-		arenaLimit := arenaBase + npage*pageSize
-		if arenaLimit > heapArenaBytes {
-			arenaLimit = heapArenaBytes
-		}
-		// Increase ha.zeroedBase so it's >= arenaLimit.
-		// We may be racing with other updates.
-		for arenaLimit > zeroedBase {
-			if atomic.Casuintptr(&ha.zeroedBase, zeroedBase, arenaLimit) {
-				break
-			}
-			zeroedBase = atomic.Loaduintptr(&ha.zeroedBase)
-			// Double check basic conditions of zeroedBase.
-			if zeroedBase <= arenaLimit && zeroedBase > arenaBase {
-				// The zeroedBase moved into the space we were trying to
-				// claim. That's very bad, and indicates someone allocated
-				// the same region we did.
-				throw("potentially overlapping in-use allocations detected")
-			}
-		}
-
-		// Move base forward and subtract from npage to move into
-		// the next arena, or finish.
-		base += arenaLimit - arenaBase
-		npage -= (arenaLimit - arenaBase) / pageSize
-	}
-	return
-}
-
-// tryAllocMSpan attempts to allocate an mspan object from
-// the P-local cache, but may fail.
-//
-// h.lock need not be held.
-//
-// This caller must ensure that its P won't change underneath
-// it during this function. Currently to ensure that we enforce
-// that the function is run on the system stack, because that's
-// the only place it is used now. In the future, this requirement
-// may be relaxed if its use is necessary elsewhere.
-//
-//go:systemstack
-func (h *mheap) tryAllocMSpan() *mspan {
-	pp := getg().m.p.ptr()
-	// If we don't have a p or the cache is empty, we can't do
-	// anything here.
-	if pp == nil || pp.mspancache.len == 0 {
-		return nil
-	}
-	// Pull off the last entry in the cache.
-	s := pp.mspancache.buf[pp.mspancache.len-1]
-	pp.mspancache.len--
-	return s
-}
-
-// allocMSpanLocked allocates an mspan object.
-//
-// h.lock must be held.
-//
-// allocMSpanLocked must be called on the system stack because
-// its caller holds the heap lock. See mheap for details.
-// Running on the system stack also ensures that we won't
-// switch Ps during this function. See tryAllocMSpan for details.
-//
-//go:systemstack
-func (h *mheap) allocMSpanLocked() *mspan {
-	assertLockHeld(&h.lock)
-
-	pp := getg().m.p.ptr()
-	if pp == nil {
-		// We don't have a p so just do the normal thing.
-		return (*mspan)(h.spanalloc.alloc())
-	}
-	// Refill the cache if necessary.
-	if pp.mspancache.len == 0 {
-		const refillCount = len(pp.mspancache.buf) / 2
-		for i := 0; i < refillCount; i++ {
-			pp.mspancache.buf[i] = (*mspan)(h.spanalloc.alloc())
-		}
-		pp.mspancache.len = refillCount
-	}
-	// Pull off the last entry in the cache.
-	s := pp.mspancache.buf[pp.mspancache.len-1]
-	pp.mspancache.len--
-	return s
-}
-
-// freeMSpanLocked free an mspan object.
-//
-// h.lock must be held.
-//
-// freeMSpanLocked must be called on the system stack because
-// its caller holds the heap lock. See mheap for details.
-// Running on the system stack also ensures that we won't
-// switch Ps during this function. See tryAllocMSpan for details.
-//
-//go:systemstack
-func (h *mheap) freeMSpanLocked(s *mspan) {
-	assertLockHeld(&h.lock)
-
-	pp := getg().m.p.ptr()
-	// First try to free the mspan directly to the cache.
-	if pp != nil && pp.mspancache.len < len(pp.mspancache.buf) {
-		pp.mspancache.buf[pp.mspancache.len] = s
-		pp.mspancache.len++
-		return
-	}
-	// Failing that (or if we don't have a p), just free it to
-	// the heap.
-	h.spanalloc.free(unsafe.Pointer(s))
-}
-
-// allocSpan allocates an mspan which owns npages worth of memory.
-//
-// If typ.manual() == false, allocSpan allocates a heap span of class spanclass
-// and updates heap accounting. If manual == true, allocSpan allocates a
-// manually-managed span (spanclass is ignored), and the caller is
-// responsible for any accounting related to its use of the span. Either
-// way, allocSpan will atomically add the bytes in the newly allocated
-// span to *sysStat.
-//
-// The returned span is fully initialized.
-//
-// h.lock must not be held.
-//
-// allocSpan must be called on the system stack both because it acquires
-// the heap lock and because it must block GC transitions.
-//
-//go:systemstack
-func (h *mheap) allocSpan(npages uintptr, typ spanAllocType, spanclass spanClass) (s *mspan) {
-	// Function-global state.
-	gp := getg()
-	base, scav := uintptr(0), uintptr(0)
-	growth := uintptr(0)
-
-	// On some platforms we need to provide physical page aligned stack
-	// allocations. Where the page size is less than the physical page
-	// size, we already manage to do this by default.
-	needPhysPageAlign := physPageAlignedStacks && typ == spanAllocStack && pageSize < physPageSize
-
-	// If the allocation is small enough, try the page cache!
-	// The page cache does not support aligned allocations, so we cannot use
-	// it if we need to provide a physical page aligned stack allocation.
-	pp := gp.m.p.ptr()
-	if !needPhysPageAlign && pp != nil && npages < pageCachePages/4 {
-		c := &pp.pcache
-
-		// If the cache is empty, refill it.
-		if c.empty() {
-			lock(&h.lock)
-			*c = h.pages.allocToCache()
-			unlock(&h.lock)
-		}
-
-		// Try to allocate from the cache.
-		base, scav = c.alloc(npages)
-		if base != 0 {
-			s = h.tryAllocMSpan()
-			if s != nil {
-				goto HaveSpan
-			}
-			// We have a base but no mspan, so we need
-			// to lock the heap.
-		}
-	}
-
-	// For one reason or another, we couldn't get the
-	// whole job done without the heap lock.
-	lock(&h.lock)
-
-	if needPhysPageAlign {
-		// Overallocate by a physical page to allow for later alignment.
-		npages += physPageSize / pageSize
-	}
-
-	if base == 0 {
-		// Try to acquire a base address.
-		base, scav = h.pages.alloc(npages)
-		if base == 0 {
-			var ok bool
-			growth, ok = h.grow(npages)
-			if !ok {
-				unlock(&h.lock)
-				return nil
-			}
-			base, scav = h.pages.alloc(npages)
-			if base == 0 {
-				throw("grew heap, but no adequate free space found")
-			}
-		}
-	}
-	if s == nil {
-		// We failed to get an mspan earlier, so grab
-		// one now that we have the heap lock.
-		s = h.allocMSpanLocked()
-	}
-
-	if needPhysPageAlign {
-		allocBase, allocPages := base, npages
-		base = alignUp(allocBase, physPageSize)
-		npages -= physPageSize / pageSize
-
-		// Return memory around the aligned allocation.
-		spaceBefore := base - allocBase
-		if spaceBefore > 0 {
-			h.pages.free(allocBase, spaceBefore/pageSize, false)
-		}
-		spaceAfter := (allocPages-npages)*pageSize - spaceBefore
-		if spaceAfter > 0 {
-			h.pages.free(base+npages*pageSize, spaceAfter/pageSize, false)
-		}
-	}
-
-	unlock(&h.lock)
-
-	if growth > 0 {
-		// We just caused a heap growth, so scavenge down what will soon be used.
-		// By scavenging inline we deal with the failure to allocate out of
-		// memory fragments by scavenging the memory fragments that are least
-		// likely to be re-used.
-		scavengeGoal := atomic.Load64(&h.scavengeGoal)
-		if retained := heapRetained(); retained+uint64(growth) > scavengeGoal {
-			// The scavenging algorithm requires the heap lock to be dropped so it
-			// can acquire it only sparingly. This is a potentially expensive operation
-			// so it frees up other goroutines to allocate in the meanwhile. In fact,
-			// they can make use of the growth we just created.
-			todo := growth
-			if overage := uintptr(retained + uint64(growth) - scavengeGoal); todo > overage {
-				todo = overage
-			}
-			h.pages.scavenge(todo)
-		}
-	}
-
-HaveSpan:
-	// At this point, both s != nil and base != 0, and the heap
-	// lock is no longer held. Initialize the span.
-	s.init(base, npages)
-	if h.allocNeedsZero(base, npages) {
-		s.needzero = 1
-	}
-	nbytes := npages * pageSize
-	if typ.manual() {
-		s.manualFreeList = 0
-		s.nelems = 0
-		s.limit = s.base() + s.npages*pageSize
-		s.state.set(mSpanManual)
-	} else {
-		// We must set span properties before the span is published anywhere
-		// since we're not holding the heap lock.
-		s.spanclass = spanclass
-		if sizeclass := spanclass.sizeclass(); sizeclass == 0 {
-			s.elemsize = nbytes
-			s.nelems = 1
-			s.divMul = 0
-		} else {
-			s.elemsize = uintptr(class_to_size[sizeclass])
-			s.nelems = nbytes / s.elemsize
-			s.divMul = class_to_divmagic[sizeclass]
-		}
-
-		// Initialize mark and allocation structures.
-		s.freeindex = 0
-		s.allocCache = ^uint64(0) // all 1s indicating all free.
-		s.gcmarkBits = newMarkBits(s.nelems)
-		s.allocBits = newAllocBits(s.nelems)
-
-		// It's safe to access h.sweepgen without the heap lock because it's
-		// only ever updated with the world stopped and we run on the
-		// systemstack which blocks a STW transition.
-		atomic.Store(&s.sweepgen, h.sweepgen)
-
-		// Now that the span is filled in, set its state. This
-		// is a publication barrier for the other fields in
-		// the span. While valid pointers into this span
-		// should never be visible until the span is returned,
-		// if the garbage collector finds an invalid pointer,
-		// access to the span may race with initialization of
-		// the span. We resolve this race by atomically
-		// setting the state after the span is fully
-		// initialized, and atomically checking the state in
-		// any situation where a pointer is suspect.
-		s.state.set(mSpanInUse)
-	}
-
-	// Commit and account for any scavenged memory that the span now owns.
-	if scav != 0 {
-		// sysUsed all the pages that are actually available
-		// in the span since some of them might be scavenged.
-		sysUsed(unsafe.Pointer(base), nbytes)
-		atomic.Xadd64(&memstats.heap_released, -int64(scav))
-	}
-	// Update stats.
-	if typ == spanAllocHeap {
-		atomic.Xadd64(&memstats.heap_inuse, int64(nbytes))
-	}
-	if typ.manual() {
-		// Manually managed memory doesn't count toward heap_sys.
-		memstats.heap_sys.add(-int64(nbytes))
-	}
-	// Update consistent stats.
-	stats := memstats.heapStats.acquire()
-	atomic.Xaddint64(&stats.committed, int64(scav))
-	atomic.Xaddint64(&stats.released, -int64(scav))
-	switch typ {
-	case spanAllocHeap:
-		atomic.Xaddint64(&stats.inHeap, int64(nbytes))
-	case spanAllocStack:
-		atomic.Xaddint64(&stats.inStacks, int64(nbytes))
-	case spanAllocPtrScalarBits:
-		atomic.Xaddint64(&stats.inPtrScalarBits, int64(nbytes))
-	case spanAllocWorkBuf:
-		atomic.Xaddint64(&stats.inWorkBufs, int64(nbytes))
-	}
-	memstats.heapStats.release()
-
-	// Publish the span in various locations.
-
-	// This is safe to call without the lock held because the slots
-	// related to this span will only ever be read or modified by
-	// this thread until pointers into the span are published (and
-	// we execute a publication barrier at the end of this function
-	// before that happens) or pageInUse is updated.
-	h.setSpans(s.base(), npages, s)
-
-	if !typ.manual() {
-		// Mark in-use span in arena page bitmap.
-		//
-		// This publishes the span to the page sweeper, so
-		// it's imperative that the span be completely initialized
-		// prior to this line.
-		arena, pageIdx, pageMask := pageIndexOf(s.base())
-		atomic.Or8(&arena.pageInUse[pageIdx], pageMask)
-
-		// Update related page sweeper stats.
-		h.pagesInUse.Add(int64(npages))
-	}
-
-	// Make sure the newly allocated span will be observed
-	// by the GC before pointers into the span are published.
-	publicationBarrier()
-
-	return s
-}
-
-// Try to add at least npage pages of memory to the heap,
-// returning how much the heap grew by and whether it worked.
-//
-// h.lock must be held.
-func (h *mheap) grow(npage uintptr) (uintptr, bool) {
-	assertLockHeld(&h.lock)
-
-	// We must grow the heap in whole palloc chunks.
-	// We call sysMap below but note that because we
-	// round up to pallocChunkPages which is on the order
-	// of MiB (generally >= to the huge page size) we
-	// won't be calling it too much.
-	ask := alignUp(npage, pallocChunkPages) * pageSize
-
-	totalGrowth := uintptr(0)
-	// This may overflow because ask could be very large
-	// and is otherwise unrelated to h.curArena.base.
-	end := h.curArena.base + ask
-	nBase := alignUp(end, physPageSize)
-	if nBase > h.curArena.end || /* overflow */ end < h.curArena.base {
-		// Not enough room in the current arena. Allocate more
-		// arena space. This may not be contiguous with the
-		// current arena, so we have to request the full ask.
-		av, asize := h.sysAlloc(ask)
-		if av == nil {
-			print("runtime: out of memory: cannot allocate ", ask, "-byte block (", memstats.heap_sys, " in use)\n")
-			return 0, false
-		}
-
-		if uintptr(av) == h.curArena.end {
-			// The new space is contiguous with the old
-			// space, so just extend the current space.
-			h.curArena.end = uintptr(av) + asize
-		} else {
-			// The new space is discontiguous. Track what
-			// remains of the current space and switch to
-			// the new space. This should be rare.
-			if size := h.curArena.end - h.curArena.base; size != 0 {
-				// Transition this space from Reserved to Prepared and mark it
-				// as released since we'll be able to start using it after updating
-				// the page allocator and releasing the lock at any time.
-				sysMap(unsafe.Pointer(h.curArena.base), size, &memstats.heap_sys)
-				// Update stats.
-				atomic.Xadd64(&memstats.heap_released, int64(size))
-				stats := memstats.heapStats.acquire()
-				atomic.Xaddint64(&stats.released, int64(size))
-				memstats.heapStats.release()
-				// Update the page allocator's structures to make this
-				// space ready for allocation.
-				h.pages.grow(h.curArena.base, size)
-				totalGrowth += size
-			}
-			// Switch to the new space.
-			h.curArena.base = uintptr(av)
-			h.curArena.end = uintptr(av) + asize
-		}
-
-		// Recalculate nBase.
-		// We know this won't overflow, because sysAlloc returned
-		// a valid region starting at h.curArena.base which is at
-		// least ask bytes in size.
-		nBase = alignUp(h.curArena.base+ask, physPageSize)
-	}
-
-	// Grow into the current arena.
-	v := h.curArena.base
-	h.curArena.base = nBase
-
-	// Transition the space we're going to use from Reserved to Prepared.
-	sysMap(unsafe.Pointer(v), nBase-v, &memstats.heap_sys)
-
-	// The memory just allocated counts as both released
-	// and idle, even though it's not yet backed by spans.
-	//
-	// The allocation is always aligned to the heap arena
-	// size which is always > physPageSize, so its safe to
-	// just add directly to heap_released.
-	atomic.Xadd64(&memstats.heap_released, int64(nBase-v))
-	stats := memstats.heapStats.acquire()
-	atomic.Xaddint64(&stats.released, int64(nBase-v))
-	memstats.heapStats.release()
-
-	// Update the page allocator's structures to make this
-	// space ready for allocation.
-	h.pages.grow(v, nBase-v)
-	totalGrowth += nBase - v
-	return totalGrowth, true
-}
-
-// Free the span back into the heap.
-func (h *mheap) freeSpan(s *mspan) {
-	systemstack(func() {
-		lock(&h.lock)
-		if msanenabled {
-			// Tell msan that this entire span is no longer in use.
-			base := unsafe.Pointer(s.base())
-			bytes := s.npages << _PageShift
-			msanfree(base, bytes)
-		}
-		if asanenabled {
-			// Tell asan that this entire span is no longer in use.
-			base := unsafe.Pointer(s.base())
-			bytes := s.npages << _PageShift
-			asanpoison(base, bytes)
-		}
-		h.freeSpanLocked(s, spanAllocHeap)
-		unlock(&h.lock)
-	})
-}
-
-// freeManual frees a manually-managed span returned by allocManual.
-// typ must be the same as the spanAllocType passed to the allocManual that
-// allocated s.
-//
-// This must only be called when gcphase == _GCoff. See mSpanState for
-// an explanation.
-//
-// freeManual must be called on the system stack because it acquires
-// the heap lock. See mheap for details.
-//
-//go:systemstack
-func (h *mheap) freeManual(s *mspan, typ spanAllocType) {
-	s.needzero = 1
-	lock(&h.lock)
-	h.freeSpanLocked(s, typ)
-	unlock(&h.lock)
-}
-
-func (h *mheap) freeSpanLocked(s *mspan, typ spanAllocType) {
-	assertLockHeld(&h.lock)
-
-	switch s.state.get() {
-	case mSpanManual:
-		if s.allocCount != 0 {
-			throw("mheap.freeSpanLocked - invalid stack free")
-		}
-	case mSpanInUse:
-		if s.allocCount != 0 || s.sweepgen != h.sweepgen {
-			print("mheap.freeSpanLocked - span ", s, " ptr ", hex(s.base()), " allocCount ", s.allocCount, " sweepgen ", s.sweepgen, "/", h.sweepgen, "\n")
-			throw("mheap.freeSpanLocked - invalid free")
-		}
-		h.pagesInUse.Add(-int64(s.npages))
-
-		// Clear in-use bit in arena page bitmap.
-		arena, pageIdx, pageMask := pageIndexOf(s.base())
-		atomic.And8(&arena.pageInUse[pageIdx], ^pageMask)
-	default:
-		throw("mheap.freeSpanLocked - invalid span state")
-	}
-
-	// Update stats.
-	//
-	// Mirrors the code in allocSpan.
-	nbytes := s.npages * pageSize
-	if typ == spanAllocHeap {
-		atomic.Xadd64(&memstats.heap_inuse, -int64(nbytes))
-	}
-	if typ.manual() {
-		// Manually managed memory doesn't count toward heap_sys, so add it back.
-		memstats.heap_sys.add(int64(nbytes))
-	}
-	// Update consistent stats.
-	stats := memstats.heapStats.acquire()
-	switch typ {
-	case spanAllocHeap:
-		atomic.Xaddint64(&stats.inHeap, -int64(nbytes))
-	case spanAllocStack:
-		atomic.Xaddint64(&stats.inStacks, -int64(nbytes))
-	case spanAllocPtrScalarBits:
-		atomic.Xaddint64(&stats.inPtrScalarBits, -int64(nbytes))
-	case spanAllocWorkBuf:
-		atomic.Xaddint64(&stats.inWorkBufs, -int64(nbytes))
-	}
-	memstats.heapStats.release()
-
-	// Mark the space as free.
-	h.pages.free(s.base(), s.npages, false)
-
-	// Free the span structure. We no longer have a use for it.
-	s.state.set(mSpanDead)
-	h.freeMSpanLocked(s)
-}
-
-// scavengeAll acquires the heap lock (blocking any additional
-// manipulation of the page allocator) and iterates over the whole
-// heap, scavenging every free page available.
-func (h *mheap) scavengeAll() {
-	// Disallow malloc or panic while holding the heap lock. We do
-	// this here because this is a non-mallocgc entry-point to
-	// the mheap API.
-	gp := getg()
-	gp.m.mallocing++
-
-	lock(&h.lock)
-	// Start a new scavenge generation so we have a chance to walk
-	// over the whole heap.
-	h.pages.scavengeStartGen()
-	unlock(&h.lock)
-
-	released := h.pages.scavenge(^uintptr(0))
-
-	lock(&h.pages.scav.lock)
-	gen := h.pages.scav.gen
-	unlock(&h.pages.scav.lock)
-
-	gp.m.mallocing--
-
-	if debug.scavtrace > 0 {
-		printScavTrace(gen, released, true)
-	}
-}
-
-//go:linkname runtime_debug_freeOSMemory runtime/debug.freeOSMemory
-func runtime_debug_freeOSMemory() {
-	GC()
-	systemstack(func() { mheap_.scavengeAll() })
-}
-
-// Initialize a new span with the given start and npages.
-func (span *mspan) init(base uintptr, npages uintptr) {
-	// span is *not* zeroed.
-	span.next = nil
-	span.prev = nil
-	span.list = nil
-	span.startAddr = base
-	span.npages = npages
-	span.allocCount = 0
-	span.spanclass = 0
-	span.elemsize = 0
-	span.speciallock.key = 0
-	span.specials = nil
-	span.needzero = 0
-	span.freeindex = 0
-	span.allocBits = nil
-	span.gcmarkBits = nil
-	span.state.set(mSpanDead)
-	lockInit(&span.speciallock, lockRankMspanSpecial)
-}
-
-func (span *mspan) inList() bool {
-	return span.list != nil
-}
-
-// Initialize an empty doubly-linked list.
-func (list *mSpanList) init() {
-	list.first = nil
-	list.last = nil
-}
-
-func (list *mSpanList) remove(span *mspan) {
-	if span.list != list {
-		print("runtime: failed mSpanList.remove span.npages=", span.npages,
-			" span=", span, " prev=", span.prev, " span.list=", span.list, " list=", list, "\n")
-		throw("mSpanList.remove")
-	}
-	if list.first == span {
-		list.first = span.next
-	} else {
-		span.prev.next = span.next
-	}
-	if list.last == span {
-		list.last = span.prev
-	} else {
-		span.next.prev = span.prev
-	}
-	span.next = nil
-	span.prev = nil
-	span.list = nil
-}
-
-func (list *mSpanList) isEmpty() bool {
-	return list.first == nil
-}
-
-func (list *mSpanList) insert(span *mspan) {
-	if span.next != nil || span.prev != nil || span.list != nil {
-		println("runtime: failed mSpanList.insert", span, span.next, span.prev, span.list)
-		throw("mSpanList.insert")
-	}
-	span.next = list.first
-	if list.first != nil {
-		// The list contains at least one span; link it in.
-		// The last span in the list doesn't change.
-		list.first.prev = span
-	} else {
-		// The list contains no spans, so this is also the last span.
-		list.last = span
-	}
-	list.first = span
-	span.list = list
-}
-
-func (list *mSpanList) insertBack(span *mspan) {
-	if span.next != nil || span.prev != nil || span.list != nil {
-		println("runtime: failed mSpanList.insertBack", span, span.next, span.prev, span.list)
-		throw("mSpanList.insertBack")
-	}
-	span.prev = list.last
-	if list.last != nil {
-		// The list contains at least one span.
-		list.last.next = span
-	} else {
-		// The list contains no spans, so this is also the first span.
-		list.first = span
-	}
-	list.last = span
-	span.list = list
-}
-
-// takeAll removes all spans from other and inserts them at the front
-// of list.
-func (list *mSpanList) takeAll(other *mSpanList) {
-	if other.isEmpty() {
-		return
-	}
-
-	// Reparent everything in other to list.
-	for s := other.first; s != nil; s = s.next {
-		s.list = list
-	}
-
-	// Concatenate the lists.
-	if list.isEmpty() {
-		*list = *other
-	} else {
-		// Neither list is empty. Put other before list.
-		other.last.next = list.first
-		list.first.prev = other.last
-		list.first = other.first
-	}
-
-	other.first, other.last = nil, nil
-}
-
-const (
-	_KindSpecialFinalizer = 1
-	_KindSpecialProfile   = 2
-	// _KindSpecialReachable is a special used for tracking
-	// reachability during testing.
-	_KindSpecialReachable = 3
-	// Note: The finalizer special must be first because if we're freeing
-	// an object, a finalizer special will cause the freeing operation
-	// to abort, and we want to keep the other special records around
-	// if that happens.
-)
-
-//go:notinheap
-type special struct {
-	next   *special // linked list in span
-	offset uint16   // span offset of object
-	kind   byte     // kind of special
-}
-
-// spanHasSpecials marks a span as having specials in the arena bitmap.
-func spanHasSpecials(s *mspan) {
-	arenaPage := (s.base() / pageSize) % pagesPerArena
-	ai := arenaIndex(s.base())
-	ha := mheap_.arenas[ai.l1()][ai.l2()]
-	atomic.Or8(&ha.pageSpecials[arenaPage/8], uint8(1)<<(arenaPage%8))
-}
-
-// spanHasNoSpecials marks a span as having no specials in the arena bitmap.
-func spanHasNoSpecials(s *mspan) {
-	arenaPage := (s.base() / pageSize) % pagesPerArena
-	ai := arenaIndex(s.base())
-	ha := mheap_.arenas[ai.l1()][ai.l2()]
-	atomic.And8(&ha.pageSpecials[arenaPage/8], ^(uint8(1) << (arenaPage % 8)))
-}
-
-// Adds the special record s to the list of special records for
-// the object p. All fields of s should be filled in except for
-// offset & next, which this routine will fill in.
-// Returns true if the special was successfully added, false otherwise.
-// (The add will fail only if a record with the same p and s->kind
-//  already exists.)
-func addspecial(p unsafe.Pointer, s *special) bool {
-	span := spanOfHeap(uintptr(p))
-	if span == nil {
-		throw("addspecial on invalid pointer")
-	}
-
-	// Ensure that the span is swept.
-	// Sweeping accesses the specials list w/o locks, so we have
-	// to synchronize with it. And it's just much safer.
-	mp := acquirem()
-	span.ensureSwept()
-
-	offset := uintptr(p) - span.base()
-	kind := s.kind
-
-	lock(&span.speciallock)
-
-	// Find splice point, check for existing record.
-	t := &span.specials
-	for {
-		x := *t
-		if x == nil {
-			break
-		}
-		if offset == uintptr(x.offset) && kind == x.kind {
-			unlock(&span.speciallock)
-			releasem(mp)
-			return false // already exists
-		}
-		if offset < uintptr(x.offset) || (offset == uintptr(x.offset) && kind < x.kind) {
-			break
-		}
-		t = &x.next
-	}
-
-	// Splice in record, fill in offset.
-	s.offset = uint16(offset)
-	s.next = *t
-	*t = s
-	spanHasSpecials(span)
-	unlock(&span.speciallock)
-	releasem(mp)
-
-	return true
-}
-
-// Removes the Special record of the given kind for the object p.
-// Returns the record if the record existed, nil otherwise.
-// The caller must FixAlloc_Free the result.
-func removespecial(p unsafe.Pointer, kind uint8) *special {
-	span := spanOfHeap(uintptr(p))
-	if span == nil {
-		throw("removespecial on invalid pointer")
-	}
-
-	// Ensure that the span is swept.
-	// Sweeping accesses the specials list w/o locks, so we have
-	// to synchronize with it. And it's just much safer.
-	mp := acquirem()
-	span.ensureSwept()
-
-	offset := uintptr(p) - span.base()
-
-	var result *special
-	lock(&span.speciallock)
-	t := &span.specials
-	for {
-		s := *t
-		if s == nil {
-			break
-		}
-		// This function is used for finalizers only, so we don't check for
-		// "interior" specials (p must be exactly equal to s->offset).
-		if offset == uintptr(s.offset) && kind == s.kind {
-			*t = s.next
-			result = s
-			break
-		}
-		t = &s.next
-	}
-	if span.specials == nil {
-		spanHasNoSpecials(span)
-	}
-	unlock(&span.speciallock)
-	releasem(mp)
-	return result
-}
-
-// The described object has a finalizer set for it.
-//
-// specialfinalizer is allocated from non-GC'd memory, so any heap
-// pointers must be specially handled.
-//
-//go:notinheap
-type specialfinalizer struct {
-	special special
-	fn      *funcval // May be a heap pointer.
-	nret    uintptr
-	fint    *_type   // May be a heap pointer, but always live.
-	ot      *ptrtype // May be a heap pointer, but always live.
-}
-
-// Adds a finalizer to the object p. Returns true if it succeeded.
-func addfinalizer(p unsafe.Pointer, f *funcval, nret uintptr, fint *_type, ot *ptrtype) bool {
-	lock(&mheap_.speciallock)
-	s := (*specialfinalizer)(mheap_.specialfinalizeralloc.alloc())
-	unlock(&mheap_.speciallock)
-	s.special.kind = _KindSpecialFinalizer
-	s.fn = f
-	s.nret = nret
-	s.fint = fint
-	s.ot = ot
-	if addspecial(p, &s.special) {
-		// This is responsible for maintaining the same
-		// GC-related invariants as markrootSpans in any
-		// situation where it's possible that markrootSpans
-		// has already run but mark termination hasn't yet.
-		if gcphase != _GCoff {
-			base, _, _ := findObject(uintptr(p), 0, 0)
-			mp := acquirem()
-			gcw := &mp.p.ptr().gcw
-			// Mark everything reachable from the object
-			// so it's retained for the finalizer.
-			scanobject(base, gcw)
-			// Mark the finalizer itself, since the
-			// special isn't part of the GC'd heap.
-			scanblock(uintptr(unsafe.Pointer(&s.fn)), goarch.PtrSize, &oneptrmask[0], gcw, nil)
-			releasem(mp)
-		}
-		return true
-	}
-
-	// There was an old finalizer
-	lock(&mheap_.speciallock)
-	mheap_.specialfinalizeralloc.free(unsafe.Pointer(s))
-	unlock(&mheap_.speciallock)
-	return false
-}
-
-// Removes the finalizer (if any) from the object p.
-func removefinalizer(p unsafe.Pointer) {
-	s := (*specialfinalizer)(unsafe.Pointer(removespecial(p, _KindSpecialFinalizer)))
-	if s == nil {
-		return // there wasn't a finalizer to remove
-	}
-	lock(&mheap_.speciallock)
-	mheap_.specialfinalizeralloc.free(unsafe.Pointer(s))
-	unlock(&mheap_.speciallock)
-}
-
-// The described object is being heap profiled.
-//
-//go:notinheap
-type specialprofile struct {
-	special special
-	b       *bucket
-}
-
-// Set the heap profile bucket associated with addr to b.
-func setprofilebucket(p unsafe.Pointer, b *bucket) {
-	lock(&mheap_.speciallock)
-	s := (*specialprofile)(mheap_.specialprofilealloc.alloc())
-	unlock(&mheap_.speciallock)
-	s.special.kind = _KindSpecialProfile
-	s.b = b
-	if !addspecial(p, &s.special) {
-		throw("setprofilebucket: profile already set")
-	}
-}
-
-// specialReachable tracks whether an object is reachable on the next
-// GC cycle. This is used by testing.
-type specialReachable struct {
-	special   special
-	done      bool
-	reachable bool
-}
-
-// specialsIter helps iterate over specials lists.
-type specialsIter struct {
-	pprev **special
-	s     *special
-}
-
-func newSpecialsIter(span *mspan) specialsIter {
-	return specialsIter{&span.specials, span.specials}
-}
-
-func (i *specialsIter) valid() bool {
-	return i.s != nil
-}
-
-func (i *specialsIter) next() {
-	i.pprev = &i.s.next
-	i.s = *i.pprev
-}
-
-// unlinkAndNext removes the current special from the list and moves
-// the iterator to the next special. It returns the unlinked special.
-func (i *specialsIter) unlinkAndNext() *special {
-	cur := i.s
-	i.s = cur.next
-	*i.pprev = i.s
-	return cur
-}
-
-// freeSpecial performs any cleanup on special s and deallocates it.
-// s must already be unlinked from the specials list.
-func freeSpecial(s *special, p unsafe.Pointer, size uintptr) {
-	switch s.kind {
-	case _KindSpecialFinalizer:
-		sf := (*specialfinalizer)(unsafe.Pointer(s))
-		queuefinalizer(p, sf.fn, sf.nret, sf.fint, sf.ot)
-		lock(&mheap_.speciallock)
-		mheap_.specialfinalizeralloc.free(unsafe.Pointer(sf))
-		unlock(&mheap_.speciallock)
-	case _KindSpecialProfile:
-		sp := (*specialprofile)(unsafe.Pointer(s))
-		mProf_Free(sp.b, size)
-		lock(&mheap_.speciallock)
-		mheap_.specialprofilealloc.free(unsafe.Pointer(sp))
-		unlock(&mheap_.speciallock)
-	case _KindSpecialReachable:
-		sp := (*specialReachable)(unsafe.Pointer(s))
-		sp.done = true
-		// The creator frees these.
-	default:
-		throw("bad special kind")
-		panic("not reached")
-	}
-}
-
-// gcBits is an alloc/mark bitmap. This is always used as *gcBits.
-//
-//go:notinheap
-type gcBits uint8
-
-// bytep returns a pointer to the n'th byte of b.
-func (b *gcBits) bytep(n uintptr) *uint8 {
-	return addb((*uint8)(b), n)
-}
-
-// bitp returns a pointer to the byte containing bit n and a mask for
-// selecting that bit from *bytep.
-func (b *gcBits) bitp(n uintptr) (bytep *uint8, mask uint8) {
-	return b.bytep(n / 8), 1 << (n % 8)
-}
-
-const gcBitsChunkBytes = uintptr(64 << 10)
-const gcBitsHeaderBytes = unsafe.Sizeof(gcBitsHeader{})
-
-type gcBitsHeader struct {
-	free uintptr // free is the index into bits of the next free byte.
-	next uintptr // *gcBits triggers recursive type bug. (issue 14620)
-}
-
-//go:notinheap
-type gcBitsArena struct {
-	// gcBitsHeader // side step recursive type bug (issue 14620) by including fields by hand.
-	free uintptr // free is the index into bits of the next free byte; read/write atomically
-	next *gcBitsArena
-	bits [gcBitsChunkBytes - gcBitsHeaderBytes]gcBits
-}
-
-var gcBitsArenas struct {
-	lock     mutex
-	free     *gcBitsArena
-	next     *gcBitsArena // Read atomically. Write atomically under lock.
-	current  *gcBitsArena
-	previous *gcBitsArena
-}
-
-// tryAlloc allocates from b or returns nil if b does not have enough room.
-// This is safe to call concurrently.
-func (b *gcBitsArena) tryAlloc(bytes uintptr) *gcBits {
-	if b == nil || atomic.Loaduintptr(&b.free)+bytes > uintptr(len(b.bits)) {
-		return nil
-	}
-	// Try to allocate from this block.
-	end := atomic.Xadduintptr(&b.free, bytes)
-	if end > uintptr(len(b.bits)) {
-		return nil
-	}
-	// There was enough room.
-	start := end - bytes
-	return &b.bits[start]
-}
-
-// newMarkBits returns a pointer to 8 byte aligned bytes
-// to be used for a span's mark bits.
-func newMarkBits(nelems uintptr) *gcBits {
-	blocksNeeded := uintptr((nelems + 63) / 64)
-	bytesNeeded := blocksNeeded * 8
-
-	// Try directly allocating from the current head arena.
-	head := (*gcBitsArena)(atomic.Loadp(unsafe.Pointer(&gcBitsArenas.next)))
-	if p := head.tryAlloc(bytesNeeded); p != nil {
-		return p
-	}
-
-	// There's not enough room in the head arena. We may need to
-	// allocate a new arena.
-	lock(&gcBitsArenas.lock)
-	// Try the head arena again, since it may have changed. Now
-	// that we hold the lock, the list head can't change, but its
-	// free position still can.
-	if p := gcBitsArenas.next.tryAlloc(bytesNeeded); p != nil {
-		unlock(&gcBitsArenas.lock)
-		return p
-	}
-
-	// Allocate a new arena. This may temporarily drop the lock.
-	fresh := newArenaMayUnlock()
-	// If newArenaMayUnlock dropped the lock, another thread may
-	// have put a fresh arena on the "next" list. Try allocating
-	// from next again.
-	if p := gcBitsArenas.next.tryAlloc(bytesNeeded); p != nil {
-		// Put fresh back on the free list.
-		// TODO: Mark it "already zeroed"
-		fresh.next = gcBitsArenas.free
-		gcBitsArenas.free = fresh
-		unlock(&gcBitsArenas.lock)
-		return p
-	}
-
-	// Allocate from the fresh arena. We haven't linked it in yet, so
-	// this cannot race and is guaranteed to succeed.
-	p := fresh.tryAlloc(bytesNeeded)
-	if p == nil {
-		throw("markBits overflow")
-	}
-
-	// Add the fresh arena to the "next" list.
-	fresh.next = gcBitsArenas.next
-	atomic.StorepNoWB(unsafe.Pointer(&gcBitsArenas.next), unsafe.Pointer(fresh))
-
-	unlock(&gcBitsArenas.lock)
-	return p
-}
-
-// newAllocBits returns a pointer to 8 byte aligned bytes
-// to be used for this span's alloc bits.
-// newAllocBits is used to provide newly initialized spans
-// allocation bits. For spans not being initialized the
-// mark bits are repurposed as allocation bits when
-// the span is swept.
-func newAllocBits(nelems uintptr) *gcBits {
-	return newMarkBits(nelems)
-}
-
-// nextMarkBitArenaEpoch establishes a new epoch for the arenas
-// holding the mark bits. The arenas are named relative to the
-// current GC cycle which is demarcated by the call to finishweep_m.
-//
-// All current spans have been swept.
-// During that sweep each span allocated room for its gcmarkBits in
-// gcBitsArenas.next block. gcBitsArenas.next becomes the gcBitsArenas.current
-// where the GC will mark objects and after each span is swept these bits
-// will be used to allocate objects.
-// gcBitsArenas.current becomes gcBitsArenas.previous where the span's
-// gcAllocBits live until all the spans have been swept during this GC cycle.
-// The span's sweep extinguishes all the references to gcBitsArenas.previous
-// by pointing gcAllocBits into the gcBitsArenas.current.
-// The gcBitsArenas.previous is released to the gcBitsArenas.free list.
-func nextMarkBitArenaEpoch() {
-	lock(&gcBitsArenas.lock)
-	if gcBitsArenas.previous != nil {
-		if gcBitsArenas.free == nil {
-			gcBitsArenas.free = gcBitsArenas.previous
-		} else {
-			// Find end of previous arenas.
-			last := gcBitsArenas.previous
-			for last = gcBitsArenas.previous; last.next != nil; last = last.next {
-			}
-			last.next = gcBitsArenas.free
-			gcBitsArenas.free = gcBitsArenas.previous
-		}
-	}
-	gcBitsArenas.previous = gcBitsArenas.current
-	gcBitsArenas.current = gcBitsArenas.next
-	atomic.StorepNoWB(unsafe.Pointer(&gcBitsArenas.next), nil) // newMarkBits calls newArena when needed
-	unlock(&gcBitsArenas.lock)
-}
-
-// newArenaMayUnlock allocates and zeroes a gcBits arena.
-// The caller must hold gcBitsArena.lock. This may temporarily release it.
-func newArenaMayUnlock() *gcBitsArena {
-	var result *gcBitsArena
-	if gcBitsArenas.free == nil {
-		unlock(&gcBitsArenas.lock)
-		result = (*gcBitsArena)(sysAlloc(gcBitsChunkBytes, &memstats.gcMiscSys))
-		if result == nil {
-			throw("runtime: cannot allocate memory")
-		}
-		lock(&gcBitsArenas.lock)
-	} else {
-		result = gcBitsArenas.free
-		gcBitsArenas.free = gcBitsArenas.free.next
-		memclrNoHeapPointers(unsafe.Pointer(result), gcBitsChunkBytes)
-	}
-	result.next = nil
-	// If result.bits is not 8 byte aligned adjust index so
-	// that &result.bits[result.free] is 8 byte aligned.
-	if uintptr(unsafe.Offsetof(gcBitsArena{}.bits))&7 == 0 {
-		result.free = 0
-	} else {
-		result.free = 8 - (uintptr(unsafe.Pointer(&result.bits[0])) & 7)
-	}
-	return result
-}
diff --git a/contrib/go/_std_1.18/src/runtime/mpagealloc.go b/contrib/go/_std_1.18/src/runtime/mpagealloc.go
deleted file mode 100644
index 2725e3b7c7..0000000000
--- a/contrib/go/_std_1.18/src/runtime/mpagealloc.go
+++ /dev/null
@@ -1,1026 +0,0 @@
-// Copyright 2019 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Page allocator.
-//
-// The page allocator manages mapped pages (defined by pageSize, NOT
-// physPageSize) for allocation and re-use. It is embedded into mheap.
-//
-// Pages are managed using a bitmap that is sharded into chunks.
-// In the bitmap, 1 means in-use, and 0 means free. The bitmap spans the
-// process's address space. Chunks are managed in a sparse-array-style structure
-// similar to mheap.arenas, since the bitmap may be large on some systems.
-//
-// The bitmap is efficiently searched by using a radix tree in combination
-// with fast bit-wise intrinsics. Allocation is performed using an address-ordered
-// first-fit approach.
-//
-// Each entry in the radix tree is a summary that describes three properties of
-// a particular region of the address space: the number of contiguous free pages
-// at the start and end of the region it represents, and the maximum number of
-// contiguous free pages found anywhere in that region.
-//
-// Each level of the radix tree is stored as one contiguous array, which represents
-// a different granularity of subdivision of the processes' address space. Thus, this
-// radix tree is actually implicit in these large arrays, as opposed to having explicit
-// dynamically-allocated pointer-based node structures. Naturally, these arrays may be
-// quite large for system with large address spaces, so in these cases they are mapped
-// into memory as needed. The leaf summaries of the tree correspond to a bitmap chunk.
-//
-// The root level (referred to as L0 and index 0 in pageAlloc.summary) has each
-// summary represent the largest section of address space (16 GiB on 64-bit systems),
-// with each subsequent level representing successively smaller subsections until we
-// reach the finest granularity at the leaves, a chunk.
-//
-// More specifically, each summary in each level (except for leaf summaries)
-// represents some number of entries in the following level. For example, each
-// summary in the root level may represent a 16 GiB region of address space,
-// and in the next level there could be 8 corresponding entries which represent 2
-// GiB subsections of that 16 GiB region, each of which could correspond to 8
-// entries in the next level which each represent 256 MiB regions, and so on.
-//
-// Thus, this design only scales to heaps so large, but can always be extended to
-// larger heaps by simply adding levels to the radix tree, which mostly costs
-// additional virtual address space. The choice of managing large arrays also means
-// that a large amount of virtual address space may be reserved by the runtime.
-
-package runtime
-
-import (
-	"runtime/internal/atomic"
-	"unsafe"
-)
-
-const (
-	// The size of a bitmap chunk, i.e. the amount of bits (that is, pages) to consider
-	// in the bitmap at once.
-	pallocChunkPages    = 1 << logPallocChunkPages
-	pallocChunkBytes    = pallocChunkPages * pageSize
-	logPallocChunkPages = 9
-	logPallocChunkBytes = logPallocChunkPages + pageShift
-
-	// The number of radix bits for each level.
-	//
-	// The value of 3 is chosen such that the block of summaries we need to scan at
-	// each level fits in 64 bytes (2^3 summaries * 8 bytes per summary), which is
-	// close to the L1 cache line width on many systems. Also, a value of 3 fits 4 tree
-	// levels perfectly into the 21-bit pallocBits summary field at the root level.
-	//
-	// The following equation explains how each of the constants relate:
-	// summaryL0Bits + (summaryLevels-1)*summaryLevelBits + logPallocChunkBytes = heapAddrBits
-	//
-	// summaryLevels is an architecture-dependent value defined in mpagealloc_*.go.
-	summaryLevelBits = 3
-	summaryL0Bits    = heapAddrBits - logPallocChunkBytes - (summaryLevels-1)*summaryLevelBits
-
-	// pallocChunksL2Bits is the number of bits of the chunk index number
-	// covered by the second level of the chunks map.
-	//
-	// See (*pageAlloc).chunks for more details. Update the documentation
-	// there should this change.
-	pallocChunksL2Bits  = heapAddrBits - logPallocChunkBytes - pallocChunksL1Bits
-	pallocChunksL1Shift = pallocChunksL2Bits
-)
-
-// Maximum searchAddr value, which indicates that the heap has no free space.
-//
-// We alias maxOffAddr just to make it clear that this is the maximum address
-// for the page allocator's search space. See maxOffAddr for details.
-var maxSearchAddr = maxOffAddr
-
-// Global chunk index.
-//
-// Represents an index into the leaf level of the radix tree.
-// Similar to arenaIndex, except instead of arenas, it divides the address
-// space into chunks.
-type chunkIdx uint
-
-// chunkIndex returns the global index of the palloc chunk containing the
-// pointer p.
-func chunkIndex(p uintptr) chunkIdx {
-	return chunkIdx((p - arenaBaseOffset) / pallocChunkBytes)
-}
-
-// chunkIndex returns the base address of the palloc chunk at index ci.
-func chunkBase(ci chunkIdx) uintptr {
-	return uintptr(ci)*pallocChunkBytes + arenaBaseOffset
-}
-
-// chunkPageIndex computes the index of the page that contains p,
-// relative to the chunk which contains p.
-func chunkPageIndex(p uintptr) uint {
-	return uint(p % pallocChunkBytes / pageSize)
-}
-
-// l1 returns the index into the first level of (*pageAlloc).chunks.
-func (i chunkIdx) l1() uint {
-	if pallocChunksL1Bits == 0 {
-		// Let the compiler optimize this away if there's no
-		// L1 map.
-		return 0
-	} else {
-		return uint(i) >> pallocChunksL1Shift
-	}
-}
-
-// l2 returns the index into the second level of (*pageAlloc).chunks.
-func (i chunkIdx) l2() uint {
-	if pallocChunksL1Bits == 0 {
-		return uint(i)
-	} else {
-		return uint(i) & (1<<pallocChunksL2Bits - 1)
-	}
-}
-
-// offAddrToLevelIndex converts an address in the offset address space
-// to the index into summary[level] containing addr.
-func offAddrToLevelIndex(level int, addr offAddr) int {
-	return int((addr.a - arenaBaseOffset) >> levelShift[level])
-}
-
-// levelIndexToOffAddr converts an index into summary[level] into
-// the corresponding address in the offset address space.
-func levelIndexToOffAddr(level, idx int) offAddr {
-	return offAddr{(uintptr(idx) << levelShift[level]) + arenaBaseOffset}
-}
-
-// addrsToSummaryRange converts base and limit pointers into a range
-// of entries for the given summary level.
-//
-// The returned range is inclusive on the lower bound and exclusive on
-// the upper bound.
-func addrsToSummaryRange(level int, base, limit uintptr) (lo int, hi int) {
-	// This is slightly more nuanced than just a shift for the exclusive
-	// upper-bound. Note that the exclusive upper bound may be within a
-	// summary at this level, meaning if we just do the obvious computation
-	// hi will end up being an inclusive upper bound. Unfortunately, just
-	// adding 1 to that is too broad since we might be on the very edge
-	// of a summary's max page count boundary for this level
-	// (1 << levelLogPages[level]). So, make limit an inclusive upper bound
-	// then shift, then add 1, so we get an exclusive upper bound at the end.
-	lo = int((base - arenaBaseOffset) >> levelShift[level])
-	hi = int(((limit-1)-arenaBaseOffset)>>levelShift[level]) + 1
-	return
-}
-
-// blockAlignSummaryRange aligns indices into the given level to that
-// level's block width (1 << levelBits[level]). It assumes lo is inclusive
-// and hi is exclusive, and so aligns them down and up respectively.
-func blockAlignSummaryRange(level int, lo, hi int) (int, int) {
-	e := uintptr(1) << levelBits[level]
-	return int(alignDown(uintptr(lo), e)), int(alignUp(uintptr(hi), e))
-}
-
-type pageAlloc struct {
-	// Radix tree of summaries.
-	//
-	// Each slice's cap represents the whole memory reservation.
-	// Each slice's len reflects the allocator's maximum known
-	// mapped heap address for that level.
-	//
-	// The backing store of each summary level is reserved in init
-	// and may or may not be committed in grow (small address spaces
-	// may commit all the memory in init).
-	//
-	// The purpose of keeping len <= cap is to enforce bounds checks
-	// on the top end of the slice so that instead of an unknown
-	// runtime segmentation fault, we get a much friendlier out-of-bounds
-	// error.
-	//
-	// To iterate over a summary level, use inUse to determine which ranges
-	// are currently available. Otherwise one might try to access
-	// memory which is only Reserved which may result in a hard fault.
-	//
-	// We may still get segmentation faults < len since some of that
-	// memory may not be committed yet.
-	summary [summaryLevels][]pallocSum
-
-	// chunks is a slice of bitmap chunks.
-	//
-	// The total size of chunks is quite large on most 64-bit platforms
-	// (O(GiB) or more) if flattened, so rather than making one large mapping
-	// (which has problems on some platforms, even when PROT_NONE) we use a
-	// two-level sparse array approach similar to the arena index in mheap.
-	//
-	// To find the chunk containing a memory address `a`, do:
-	//   chunkOf(chunkIndex(a))
-	//
-	// Below is a table describing the configuration for chunks for various
-	// heapAddrBits supported by the runtime.
-	//
-	// heapAddrBits | L1 Bits | L2 Bits | L2 Entry Size
-	// ------------------------------------------------
-	// 32           | 0       | 10      | 128 KiB
-	// 33 (iOS)     | 0       | 11      | 256 KiB
-	// 48           | 13      | 13      | 1 MiB
-	//
-	// There's no reason to use the L1 part of chunks on 32-bit, the
-	// address space is small so the L2 is small. For platforms with a
-	// 48-bit address space, we pick the L1 such that the L2 is 1 MiB
-	// in size, which is a good balance between low granularity without
-	// making the impact on BSS too high (note the L1 is stored directly
-	// in pageAlloc).
-	//
-	// To iterate over the bitmap, use inUse to determine which ranges
-	// are currently available. Otherwise one might iterate over unused
-	// ranges.
-	//
-	// Protected by mheapLock.
-	//
-	// TODO(mknyszek): Consider changing the definition of the bitmap
-	// such that 1 means free and 0 means in-use so that summaries and
-	// the bitmaps align better on zero-values.
-	chunks [1 << pallocChunksL1Bits]*[1 << pallocChunksL2Bits]pallocData
-
-	// The address to start an allocation search with. It must never
-	// point to any memory that is not contained in inUse, i.e.
-	// inUse.contains(searchAddr.addr()) must always be true. The one
-	// exception to this rule is that it may take on the value of
-	// maxOffAddr to indicate that the heap is exhausted.
-	//
-	// We guarantee that all valid heap addresses below this value
-	// are allocated and not worth searching.
-	searchAddr offAddr
-
-	// start and end represent the chunk indices
-	// which pageAlloc knows about. It assumes
-	// chunks in the range [start, end) are
-	// currently ready to use.
-	start, end chunkIdx
-
-	// inUse is a slice of ranges of address space which are
-	// known by the page allocator to be currently in-use (passed
-	// to grow).
-	//
-	// This field is currently unused on 32-bit architectures but
-	// is harmless to track. We care much more about having a
-	// contiguous heap in these cases and take additional measures
-	// to ensure that, so in nearly all cases this should have just
-	// 1 element.
-	//
-	// All access is protected by the mheapLock.
-	inUse addrRanges
-
-	// scav stores the scavenger state.
-	scav struct {
-		lock mutex
-
-		// inUse is a slice of ranges of address space which have not
-		// yet been looked at by the scavenger.
-		//
-		// Protected by lock.
-		inUse addrRanges
-
-		// gen is the scavenge generation number.
-		//
-		// Protected by lock.
-		gen uint32
-
-		// reservationBytes is how large of a reservation should be made
-		// in bytes of address space for each scavenge iteration.
-		//
-		// Protected by lock.
-		reservationBytes uintptr
-
-		// released is the amount of memory released this generation.
-		//
-		// Updated atomically.
-		released uintptr
-
-		// scavLWM is the lowest (offset) address that the scavenger reached this
-		// scavenge generation.
-		//
-		// Protected by lock.
-		scavLWM offAddr
-
-		// freeHWM is the highest (offset) address of a page that was freed to
-		// the page allocator this scavenge generation.
-		//
-		// Protected by mheapLock.
-		freeHWM offAddr
-	}
-
-	// mheap_.lock. This level of indirection makes it possible
-	// to test pageAlloc indepedently of the runtime allocator.
-	mheapLock *mutex
-
-	// sysStat is the runtime memstat to update when new system
-	// memory is committed by the pageAlloc for allocation metadata.
-	sysStat *sysMemStat
-
-	// Whether or not this struct is being used in tests.
-	test bool
-}
-
-func (p *pageAlloc) init(mheapLock *mutex, sysStat *sysMemStat) {
-	if levelLogPages[0] > logMaxPackedValue {
-		// We can't represent 1<<levelLogPages[0] pages, the maximum number
-		// of pages we need to represent at the root level, in a summary, which
-		// is a big problem. Throw.
-		print("runtime: root level max pages = ", 1<<levelLogPages[0], "\n")
-		print("runtime: summary max pages = ", maxPackedValue, "\n")
-		throw("root level max pages doesn't fit in summary")
-	}
-	p.sysStat = sysStat
-
-	// Initialize p.inUse.
-	p.inUse.init(sysStat)
-
-	// System-dependent initialization.
-	p.sysInit()
-
-	// Start with the searchAddr in a state indicating there's no free memory.
-	p.searchAddr = maxSearchAddr
-
-	// Set the mheapLock.
-	p.mheapLock = mheapLock
-
-	// Initialize scavenge tracking state.
-	p.scav.scavLWM = maxSearchAddr
-}
-
-// tryChunkOf returns the bitmap data for the given chunk.
-//
-// Returns nil if the chunk data has not been mapped.
-func (p *pageAlloc) tryChunkOf(ci chunkIdx) *pallocData {
-	l2 := p.chunks[ci.l1()]
-	if l2 == nil {
-		return nil
-	}
-	return &l2[ci.l2()]
-}
-
-// chunkOf returns the chunk at the given chunk index.
-//
-// The chunk index must be valid or this method may throw.
-func (p *pageAlloc) chunkOf(ci chunkIdx) *pallocData {
-	return &p.chunks[ci.l1()][ci.l2()]
-}
-
-// grow sets up the metadata for the address range [base, base+size).
-// It may allocate metadata, in which case *p.sysStat will be updated.
-//
-// p.mheapLock must be held.
-func (p *pageAlloc) grow(base, size uintptr) {
-	assertLockHeld(p.mheapLock)
-
-	// Round up to chunks, since we can't deal with increments smaller
-	// than chunks. Also, sysGrow expects aligned values.
-	limit := alignUp(base+size, pallocChunkBytes)
-	base = alignDown(base, pallocChunkBytes)
-
-	// Grow the summary levels in a system-dependent manner.
-	// We just update a bunch of additional metadata here.
-	p.sysGrow(base, limit)
-
-	// Update p.start and p.end.
-	// If no growth happened yet, start == 0. This is generally
-	// safe since the zero page is unmapped.
-	firstGrowth := p.start == 0
-	start, end := chunkIndex(base), chunkIndex(limit)
-	if firstGrowth || start < p.start {
-		p.start = start
-	}
-	if end > p.end {
-		p.end = end
-	}
-	// Note that [base, limit) will never overlap with any existing
-	// range inUse because grow only ever adds never-used memory
-	// regions to the page allocator.
-	p.inUse.add(makeAddrRange(base, limit))
-
-	// A grow operation is a lot like a free operation, so if our
-	// chunk ends up below p.searchAddr, update p.searchAddr to the
-	// new address, just like in free.
-	if b := (offAddr{base}); b.lessThan(p.searchAddr) {
-		p.searchAddr = b
-	}
-
-	// Add entries into chunks, which is sparse, if needed. Then,
-	// initialize the bitmap.
-	//
-	// Newly-grown memory is always considered scavenged.
-	// Set all the bits in the scavenged bitmaps high.
-	for c := chunkIndex(base); c < chunkIndex(limit); c++ {
-		if p.chunks[c.l1()] == nil {
-			// Create the necessary l2 entry.
-			//
-			// Store it atomically to avoid races with readers which
-			// don't acquire the heap lock.
-			r := sysAlloc(unsafe.Sizeof(*p.chunks[0]), p.sysStat)
-			if r == nil {
-				throw("pageAlloc: out of memory")
-			}
-			atomic.StorepNoWB(unsafe.Pointer(&p.chunks[c.l1()]), r)
-		}
-		p.chunkOf(c).scavenged.setRange(0, pallocChunkPages)
-	}
-
-	// Update summaries accordingly. The grow acts like a free, so
-	// we need to ensure this newly-free memory is visible in the
-	// summaries.
-	p.update(base, size/pageSize, true, false)
-}
-
-// update updates heap metadata. It must be called each time the bitmap
-// is updated.
-//
-// If contig is true, update does some optimizations assuming that there was
-// a contiguous allocation or free between addr and addr+npages. alloc indicates
-// whether the operation performed was an allocation or a free.
-//
-// p.mheapLock must be held.
-func (p *pageAlloc) update(base, npages uintptr, contig, alloc bool) {
-	assertLockHeld(p.mheapLock)
-
-	// base, limit, start, and end are inclusive.
-	limit := base + npages*pageSize - 1
-	sc, ec := chunkIndex(base), chunkIndex(limit)
-
-	// Handle updating the lowest level first.
-	if sc == ec {
-		// Fast path: the allocation doesn't span more than one chunk,
-		// so update this one and if the summary didn't change, return.
-		x := p.summary[len(p.summary)-1][sc]
-		y := p.chunkOf(sc).summarize()
-		if x == y {
-			return
-		}
-		p.summary[len(p.summary)-1][sc] = y
-	} else if contig {
-		// Slow contiguous path: the allocation spans more than one chunk
-		// and at least one summary is guaranteed to change.
-		summary := p.summary[len(p.summary)-1]
-
-		// Update the summary for chunk sc.
-		summary[sc] = p.chunkOf(sc).summarize()
-
-		// Update the summaries for chunks in between, which are
-		// either totally allocated or freed.
-		whole := p.summary[len(p.summary)-1][sc+1 : ec]
-		if alloc {
-			// Should optimize into a memclr.
-			for i := range whole {
-				whole[i] = 0
-			}
-		} else {
-			for i := range whole {
-				whole[i] = freeChunkSum
-			}
-		}
-
-		// Update the summary for chunk ec.
-		summary[ec] = p.chunkOf(ec).summarize()
-	} else {
-		// Slow general path: the allocation spans more than one chunk
-		// and at least one summary is guaranteed to change.
-		//
-		// We can't assume a contiguous allocation happened, so walk over
-		// every chunk in the range and manually recompute the summary.
-		summary := p.summary[len(p.summary)-1]
-		for c := sc; c <= ec; c++ {
-			summary[c] = p.chunkOf(c).summarize()
-		}
-	}
-
-	// Walk up the radix tree and update the summaries appropriately.
-	changed := true
-	for l := len(p.summary) - 2; l >= 0 && changed; l-- {
-		// Update summaries at level l from summaries at level l+1.
-		changed = false
-
-		// "Constants" for the previous level which we
-		// need to compute the summary from that level.
-		logEntriesPerBlock := levelBits[l+1]
-		logMaxPages := levelLogPages[l+1]
-
-		// lo and hi describe all the parts of the level we need to look at.
-		lo, hi := addrsToSummaryRange(l, base, limit+1)
-
-		// Iterate over each block, updating the corresponding summary in the less-granular level.
-		for i := lo; i < hi; i++ {
-			children := p.summary[l+1][i<<logEntriesPerBlock : (i+1)<<logEntriesPerBlock]
-			sum := mergeSummaries(children, logMaxPages)
-			old := p.summary[l][i]
-			if old != sum {
-				changed = true
-				p.summary[l][i] = sum
-			}
-		}
-	}
-}
-
-// allocRange marks the range of memory [base, base+npages*pageSize) as
-// allocated. It also updates the summaries to reflect the newly-updated
-// bitmap.
-//
-// Returns the amount of scavenged memory in bytes present in the
-// allocated range.
-//
-// p.mheapLock must be held.
-func (p *pageAlloc) allocRange(base, npages uintptr) uintptr {
-	assertLockHeld(p.mheapLock)
-
-	limit := base + npages*pageSize - 1
-	sc, ec := chunkIndex(base), chunkIndex(limit)
-	si, ei := chunkPageIndex(base), chunkPageIndex(limit)
-
-	scav := uint(0)
-	if sc == ec {
-		// The range doesn't cross any chunk boundaries.
-		chunk := p.chunkOf(sc)
-		scav += chunk.scavenged.popcntRange(si, ei+1-si)
-		chunk.allocRange(si, ei+1-si)
-	} else {
-		// The range crosses at least one chunk boundary.
-		chunk := p.chunkOf(sc)
-		scav += chunk.scavenged.popcntRange(si, pallocChunkPages-si)
-		chunk.allocRange(si, pallocChunkPages-si)
-		for c := sc + 1; c < ec; c++ {
-			chunk := p.chunkOf(c)
-			scav += chunk.scavenged.popcntRange(0, pallocChunkPages)
-			chunk.allocAll()
-		}
-		chunk = p.chunkOf(ec)
-		scav += chunk.scavenged.popcntRange(0, ei+1)
-		chunk.allocRange(0, ei+1)
-	}
-	p.update(base, npages, true, true)
-	return uintptr(scav) * pageSize
-}
-
-// findMappedAddr returns the smallest mapped offAddr that is
-// >= addr. That is, if addr refers to mapped memory, then it is
-// returned. If addr is higher than any mapped region, then
-// it returns maxOffAddr.
-//
-// p.mheapLock must be held.
-func (p *pageAlloc) findMappedAddr(addr offAddr) offAddr {
-	assertLockHeld(p.mheapLock)
-
-	// If we're not in a test, validate first by checking mheap_.arenas.
-	// This is a fast path which is only safe to use outside of testing.
-	ai := arenaIndex(addr.addr())
-	if p.test || mheap_.arenas[ai.l1()] == nil || mheap_.arenas[ai.l1()][ai.l2()] == nil {
-		vAddr, ok := p.inUse.findAddrGreaterEqual(addr.addr())
-		if ok {
-			return offAddr{vAddr}
-		} else {
-			// The candidate search address is greater than any
-			// known address, which means we definitely have no
-			// free memory left.
-			return maxOffAddr
-		}
-	}
-	return addr
-}
-
-// find searches for the first (address-ordered) contiguous free region of
-// npages in size and returns a base address for that region.
-//
-// It uses p.searchAddr to prune its search and assumes that no palloc chunks
-// below chunkIndex(p.searchAddr) contain any free memory at all.
-//
-// find also computes and returns a candidate p.searchAddr, which may or
-// may not prune more of the address space than p.searchAddr already does.
-// This candidate is always a valid p.searchAddr.
-//
-// find represents the slow path and the full radix tree search.
-//
-// Returns a base address of 0 on failure, in which case the candidate
-// searchAddr returned is invalid and must be ignored.
-//
-// p.mheapLock must be held.
-func (p *pageAlloc) find(npages uintptr) (uintptr, offAddr) {
-	assertLockHeld(p.mheapLock)
-
-	// Search algorithm.
-	//
-	// This algorithm walks each level l of the radix tree from the root level
-	// to the leaf level. It iterates over at most 1 << levelBits[l] of entries
-	// in a given level in the radix tree, and uses the summary information to
-	// find either:
-	//  1) That a given subtree contains a large enough contiguous region, at
-	//     which point it continues iterating on the next level, or
-	//  2) That there are enough contiguous boundary-crossing bits to satisfy
-	//     the allocation, at which point it knows exactly where to start
-	//     allocating from.
-	//
-	// i tracks the index into the current level l's structure for the
-	// contiguous 1 << levelBits[l] entries we're actually interested in.
-	//
-	// NOTE: Technically this search could allocate a region which crosses
-	// the arenaBaseOffset boundary, which when arenaBaseOffset != 0, is
-	// a discontinuity. However, the only way this could happen is if the
-	// page at the zero address is mapped, and this is impossible on
-	// every system we support where arenaBaseOffset != 0. So, the
-	// discontinuity is already encoded in the fact that the OS will never
-	// map the zero page for us, and this function doesn't try to handle
-	// this case in any way.
-
-	// i is the beginning of the block of entries we're searching at the
-	// current level.
-	i := 0
-
-	// firstFree is the region of address space that we are certain to
-	// find the first free page in the heap. base and bound are the inclusive
-	// bounds of this window, and both are addresses in the linearized, contiguous
-	// view of the address space (with arenaBaseOffset pre-added). At each level,
-	// this window is narrowed as we find the memory region containing the
-	// first free page of memory. To begin with, the range reflects the
-	// full process address space.
-	//
-	// firstFree is updated by calling foundFree each time free space in the
-	// heap is discovered.
-	//
-	// At the end of the search, base.addr() is the best new
-	// searchAddr we could deduce in this search.
-	firstFree := struct {
-		base, bound offAddr
-	}{
-		base:  minOffAddr,
-		bound: maxOffAddr,
-	}
-	// foundFree takes the given address range [addr, addr+size) and
-	// updates firstFree if it is a narrower range. The input range must
-	// either be fully contained within firstFree or not overlap with it
-	// at all.
-	//
-	// This way, we'll record the first summary we find with any free
-	// pages on the root level and narrow that down if we descend into
-	// that summary. But as soon as we need to iterate beyond that summary
-	// in a level to find a large enough range, we'll stop narrowing.
-	foundFree := func(addr offAddr, size uintptr) {
-		if firstFree.base.lessEqual(addr) && addr.add(size-1).lessEqual(firstFree.bound) {
-			// This range fits within the current firstFree window, so narrow
-			// down the firstFree window to the base and bound of this range.
-			firstFree.base = addr
-			firstFree.bound = addr.add(size - 1)
-		} else if !(addr.add(size-1).lessThan(firstFree.base) || firstFree.bound.lessThan(addr)) {
-			// This range only partially overlaps with the firstFree range,
-			// so throw.
-			print("runtime: addr = ", hex(addr.addr()), ", size = ", size, "\n")
-			print("runtime: base = ", hex(firstFree.base.addr()), ", bound = ", hex(firstFree.bound.addr()), "\n")
-			throw("range partially overlaps")
-		}
-	}
-
-	// lastSum is the summary which we saw on the previous level that made us
-	// move on to the next level. Used to print additional information in the
-	// case of a catastrophic failure.
-	// lastSumIdx is that summary's index in the previous level.
-	lastSum := packPallocSum(0, 0, 0)
-	lastSumIdx := -1
-
-nextLevel:
-	for l := 0; l < len(p.summary); l++ {
-		// For the root level, entriesPerBlock is the whole level.
-		entriesPerBlock := 1 << levelBits[l]
-		logMaxPages := levelLogPages[l]
-
-		// We've moved into a new level, so let's update i to our new
-		// starting index. This is a no-op for level 0.
-		i <<= levelBits[l]
-
-		// Slice out the block of entries we care about.
-		entries := p.summary[l][i : i+entriesPerBlock]
-
-		// Determine j0, the first index we should start iterating from.
-		// The searchAddr may help us eliminate iterations if we followed the
-		// searchAddr on the previous level or we're on the root leve, in which
-		// case the searchAddr should be the same as i after levelShift.
-		j0 := 0
-		if searchIdx := offAddrToLevelIndex(l, p.searchAddr); searchIdx&^(entriesPerBlock-1) == i {
-			j0 = searchIdx & (entriesPerBlock - 1)
-		}
-
-		// Run over the level entries looking for
-		// a contiguous run of at least npages either
-		// within an entry or across entries.
-		//
-		// base contains the page index (relative to
-		// the first entry's first page) of the currently
-		// considered run of consecutive pages.
-		//
-		// size contains the size of the currently considered
-		// run of consecutive pages.
-		var base, size uint
-		for j := j0; j < len(entries); j++ {
-			sum := entries[j]
-			if sum == 0 {
-				// A full entry means we broke any streak and
-				// that we should skip it altogether.
-				size = 0
-				continue
-			}
-
-			// We've encountered a non-zero summary which means
-			// free memory, so update firstFree.
-			foundFree(levelIndexToOffAddr(l, i+j), (uintptr(1)<<logMaxPages)*pageSize)
-
-			s := sum.start()
-			if size+s >= uint(npages) {
-				// If size == 0 we don't have a run yet,
-				// which means base isn't valid. So, set
-				// base to the first page in this block.
-				if size == 0 {
-					base = uint(j) << logMaxPages
-				}
-				// We hit npages; we're done!
-				size += s
-				break
-			}
-			if sum.max() >= uint(npages) {
-				// The entry itself contains npages contiguous
-				// free pages, so continue on the next level
-				// to find that run.
-				i += j
-				lastSumIdx = i
-				lastSum = sum
-				continue nextLevel
-			}
-			if size == 0 || s < 1<<logMaxPages {
-				// We either don't have a current run started, or this entry
-				// isn't totally free (meaning we can't continue the current
-				// one), so try to begin a new run by setting size and base
-				// based on sum.end.
-				size = sum.end()
-				base = uint(j+1)<<logMaxPages - size
-				continue
-			}
-			// The entry is completely free, so continue the run.
-			size += 1 << logMaxPages
-		}
-		if size >= uint(npages) {
-			// We found a sufficiently large run of free pages straddling
-			// some boundary, so compute the address and return it.
-			addr := levelIndexToOffAddr(l, i).add(uintptr(base) * pageSize).addr()
-			return addr, p.findMappedAddr(firstFree.base)
-		}
-		if l == 0 {
-			// We're at level zero, so that means we've exhausted our search.
-			return 0, maxSearchAddr
-		}
-
-		// We're not at level zero, and we exhausted the level we were looking in.
-		// This means that either our calculations were wrong or the level above
-		// lied to us. In either case, dump some useful state and throw.
-		print("runtime: summary[", l-1, "][", lastSumIdx, "] = ", lastSum.start(), ", ", lastSum.max(), ", ", lastSum.end(), "\n")
-		print("runtime: level = ", l, ", npages = ", npages, ", j0 = ", j0, "\n")
-		print("runtime: p.searchAddr = ", hex(p.searchAddr.addr()), ", i = ", i, "\n")
-		print("runtime: levelShift[level] = ", levelShift[l], ", levelBits[level] = ", levelBits[l], "\n")
-		for j := 0; j < len(entries); j++ {
-			sum := entries[j]
-			print("runtime: summary[", l, "][", i+j, "] = (", sum.start(), ", ", sum.max(), ", ", sum.end(), ")\n")
-		}
-		throw("bad summary data")
-	}
-
-	// Since we've gotten to this point, that means we haven't found a
-	// sufficiently-sized free region straddling some boundary (chunk or larger).
-	// This means the last summary we inspected must have had a large enough "max"
-	// value, so look inside the chunk to find a suitable run.
-	//
-	// After iterating over all levels, i must contain a chunk index which
-	// is what the final level represents.
-	ci := chunkIdx(i)
-	j, searchIdx := p.chunkOf(ci).find(npages, 0)
-	if j == ^uint(0) {
-		// We couldn't find any space in this chunk despite the summaries telling
-		// us it should be there. There's likely a bug, so dump some state and throw.
-		sum := p.summary[len(p.summary)-1][i]
-		print("runtime: summary[", len(p.summary)-1, "][", i, "] = (", sum.start(), ", ", sum.max(), ", ", sum.end(), ")\n")
-		print("runtime: npages = ", npages, "\n")
-		throw("bad summary data")
-	}
-
-	// Compute the address at which the free space starts.
-	addr := chunkBase(ci) + uintptr(j)*pageSize
-
-	// Since we actually searched the chunk, we may have
-	// found an even narrower free window.
-	searchAddr := chunkBase(ci) + uintptr(searchIdx)*pageSize
-	foundFree(offAddr{searchAddr}, chunkBase(ci+1)-searchAddr)
-	return addr, p.findMappedAddr(firstFree.base)
-}
-
-// alloc allocates npages worth of memory from the page heap, returning the base
-// address for the allocation and the amount of scavenged memory in bytes
-// contained in the region [base address, base address + npages*pageSize).
-//
-// Returns a 0 base address on failure, in which case other returned values
-// should be ignored.
-//
-// p.mheapLock must be held.
-//
-// Must run on the system stack because p.mheapLock must be held.
-//
-//go:systemstack
-func (p *pageAlloc) alloc(npages uintptr) (addr uintptr, scav uintptr) {
-	assertLockHeld(p.mheapLock)
-
-	// If the searchAddr refers to a region which has a higher address than
-	// any known chunk, then we know we're out of memory.
-	if chunkIndex(p.searchAddr.addr()) >= p.end {
-		return 0, 0
-	}
-
-	// If npages has a chance of fitting in the chunk where the searchAddr is,
-	// search it directly.
-	searchAddr := minOffAddr
-	if pallocChunkPages-chunkPageIndex(p.searchAddr.addr()) >= uint(npages) {
-		// npages is guaranteed to be no greater than pallocChunkPages here.
-		i := chunkIndex(p.searchAddr.addr())
-		if max := p.summary[len(p.summary)-1][i].max(); max >= uint(npages) {
-			j, searchIdx := p.chunkOf(i).find(npages, chunkPageIndex(p.searchAddr.addr()))
-			if j == ^uint(0) {
-				print("runtime: max = ", max, ", npages = ", npages, "\n")
-				print("runtime: searchIdx = ", chunkPageIndex(p.searchAddr.addr()), ", p.searchAddr = ", hex(p.searchAddr.addr()), "\n")
-				throw("bad summary data")
-			}
-			addr = chunkBase(i) + uintptr(j)*pageSize
-			searchAddr = offAddr{chunkBase(i) + uintptr(searchIdx)*pageSize}
-			goto Found
-		}
-	}
-	// We failed to use a searchAddr for one reason or another, so try
-	// the slow path.
-	addr, searchAddr = p.find(npages)
-	if addr == 0 {
-		if npages == 1 {
-			// We failed to find a single free page, the smallest unit
-			// of allocation. This means we know the heap is completely
-			// exhausted. Otherwise, the heap still might have free
-			// space in it, just not enough contiguous space to
-			// accommodate npages.
-			p.searchAddr = maxSearchAddr
-		}
-		return 0, 0
-	}
-Found:
-	// Go ahead and actually mark the bits now that we have an address.
-	scav = p.allocRange(addr, npages)
-
-	// If we found a higher searchAddr, we know that all the
-	// heap memory before that searchAddr in an offset address space is
-	// allocated, so bump p.searchAddr up to the new one.
-	if p.searchAddr.lessThan(searchAddr) {
-		p.searchAddr = searchAddr
-	}
-	return addr, scav
-}
-
-// free returns npages worth of memory starting at base back to the page heap.
-//
-// p.mheapLock must be held.
-//
-// Must run on the system stack because p.mheapLock must be held.
-//
-//go:systemstack
-func (p *pageAlloc) free(base, npages uintptr, scavenged bool) {
-	assertLockHeld(p.mheapLock)
-
-	// If we're freeing pages below the p.searchAddr, update searchAddr.
-	if b := (offAddr{base}); b.lessThan(p.searchAddr) {
-		p.searchAddr = b
-	}
-	limit := base + npages*pageSize - 1
-	if !scavenged {
-		// Update the free high watermark for the scavenger.
-		if offLimit := (offAddr{limit}); p.scav.freeHWM.lessThan(offLimit) {
-			p.scav.freeHWM = offLimit
-		}
-	}
-	if npages == 1 {
-		// Fast path: we're clearing a single bit, and we know exactly
-		// where it is, so mark it directly.
-		i := chunkIndex(base)
-		p.chunkOf(i).free1(chunkPageIndex(base))
-	} else {
-		// Slow path: we're clearing more bits so we may need to iterate.
-		sc, ec := chunkIndex(base), chunkIndex(limit)
-		si, ei := chunkPageIndex(base), chunkPageIndex(limit)
-
-		if sc == ec {
-			// The range doesn't cross any chunk boundaries.
-			p.chunkOf(sc).free(si, ei+1-si)
-		} else {
-			// The range crosses at least one chunk boundary.
-			p.chunkOf(sc).free(si, pallocChunkPages-si)
-			for c := sc + 1; c < ec; c++ {
-				p.chunkOf(c).freeAll()
-			}
-			p.chunkOf(ec).free(0, ei+1)
-		}
-	}
-	p.update(base, npages, true, false)
-}
-
-const (
-	pallocSumBytes = unsafe.Sizeof(pallocSum(0))
-
-	// maxPackedValue is the maximum value that any of the three fields in
-	// the pallocSum may take on.
-	maxPackedValue    = 1 << logMaxPackedValue
-	logMaxPackedValue = logPallocChunkPages + (summaryLevels-1)*summaryLevelBits
-
-	freeChunkSum = pallocSum(uint64(pallocChunkPages) |
-		uint64(pallocChunkPages<<logMaxPackedValue) |
-		uint64(pallocChunkPages<<(2*logMaxPackedValue)))
-)
-
-// pallocSum is a packed summary type which packs three numbers: start, max,
-// and end into a single 8-byte value. Each of these values are a summary of
-// a bitmap and are thus counts, each of which may have a maximum value of
-// 2^21 - 1, or all three may be equal to 2^21. The latter case is represented
-// by just setting the 64th bit.
-type pallocSum uint64
-
-// packPallocSum takes a start, max, and end value and produces a pallocSum.
-func packPallocSum(start, max, end uint) pallocSum {
-	if max == maxPackedValue {
-		return pallocSum(uint64(1 << 63))
-	}
-	return pallocSum((uint64(start) & (maxPackedValue - 1)) |
-		((uint64(max) & (maxPackedValue - 1)) << logMaxPackedValue) |
-		((uint64(end) & (maxPackedValue - 1)) << (2 * logMaxPackedValue)))
-}
-
-// start extracts the start value from a packed sum.
-func (p pallocSum) start() uint {
-	if uint64(p)&uint64(1<<63) != 0 {
-		return maxPackedValue
-	}
-	return uint(uint64(p) & (maxPackedValue - 1))
-}
-
-// max extracts the max value from a packed sum.
-func (p pallocSum) max() uint {
-	if uint64(p)&uint64(1<<63) != 0 {
-		return maxPackedValue
-	}
-	return uint((uint64(p) >> logMaxPackedValue) & (maxPackedValue - 1))
-}
-
-// end extracts the end value from a packed sum.
-func (p pallocSum) end() uint {
-	if uint64(p)&uint64(1<<63) != 0 {
-		return maxPackedValue
-	}
-	return uint((uint64(p) >> (2 * logMaxPackedValue)) & (maxPackedValue - 1))
-}
-
-// unpack unpacks all three values from the summary.
-func (p pallocSum) unpack() (uint, uint, uint) {
-	if uint64(p)&uint64(1<<63) != 0 {
-		return maxPackedValue, maxPackedValue, maxPackedValue
-	}
-	return uint(uint64(p) & (maxPackedValue - 1)),
-		uint((uint64(p) >> logMaxPackedValue) & (maxPackedValue - 1)),
-		uint((uint64(p) >> (2 * logMaxPackedValue)) & (maxPackedValue - 1))
-}
-
-// mergeSummaries merges consecutive summaries which may each represent at
-// most 1 << logMaxPagesPerSum pages each together into one.
-func mergeSummaries(sums []pallocSum, logMaxPagesPerSum uint) pallocSum {
-	// Merge the summaries in sums into one.
-	//
-	// We do this by keeping a running summary representing the merged
-	// summaries of sums[:i] in start, max, and end.
-	start, max, end := sums[0].unpack()
-	for i := 1; i < len(sums); i++ {
-		// Merge in sums[i].
-		si, mi, ei := sums[i].unpack()
-
-		// Merge in sums[i].start only if the running summary is
-		// completely free, otherwise this summary's start
-		// plays no role in the combined sum.
-		if start == uint(i)<<logMaxPagesPerSum {
-			start += si
-		}
-
-		// Recompute the max value of the running sum by looking
-		// across the boundary between the running sum and sums[i]
-		// and at the max sums[i], taking the greatest of those two
-		// and the max of the running sum.
-		if end+si > max {
-			max = end + si
-		}
-		if mi > max {
-			max = mi
-		}
-
-		// Merge in end by checking if this new summary is totally
-		// free. If it is, then we want to extend the running sum's
-		// end by the new summary. If not, then we have some alloc'd
-		// pages in there and we just want to take the end value in
-		// sums[i].
-		if ei == 1<<logMaxPagesPerSum {
-			end += 1 << logMaxPagesPerSum
-		} else {
-			end = ei
-		}
-	}
-	return packPallocSum(start, max, end)
-}
diff --git a/contrib/go/_std_1.18/src/runtime/mpagealloc_64bit.go b/contrib/go/_std_1.18/src/runtime/mpagealloc_64bit.go
deleted file mode 100644
index 1bacfbe0fa..0000000000
--- a/contrib/go/_std_1.18/src/runtime/mpagealloc_64bit.go
+++ /dev/null
@@ -1,178 +0,0 @@
-// Copyright 2019 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build amd64 || arm64 || mips64 || mips64le || ppc64 || ppc64le || riscv64 || s390x
-
-package runtime
-
-import "unsafe"
-
-const (
-	// The number of levels in the radix tree.
-	summaryLevels = 5
-
-	// Constants for testing.
-	pageAlloc32Bit = 0
-	pageAlloc64Bit = 1
-
-	// Number of bits needed to represent all indices into the L1 of the
-	// chunks map.
-	//
-	// See (*pageAlloc).chunks for more details. Update the documentation
-	// there should this number change.
-	pallocChunksL1Bits = 13
-)
-
-// levelBits is the number of bits in the radix for a given level in the super summary
-// structure.
-//
-// The sum of all the entries of levelBits should equal heapAddrBits.
-var levelBits = [summaryLevels]uint{
-	summaryL0Bits,
-	summaryLevelBits,
-	summaryLevelBits,
-	summaryLevelBits,
-	summaryLevelBits,
-}
-
-// levelShift is the number of bits to shift to acquire the radix for a given level
-// in the super summary structure.
-//
-// With levelShift, one can compute the index of the summary at level l related to a
-// pointer p by doing:
-//   p >> levelShift[l]
-var levelShift = [summaryLevels]uint{
-	heapAddrBits - summaryL0Bits,
-	heapAddrBits - summaryL0Bits - 1*summaryLevelBits,
-	heapAddrBits - summaryL0Bits - 2*summaryLevelBits,
-	heapAddrBits - summaryL0Bits - 3*summaryLevelBits,
-	heapAddrBits - summaryL0Bits - 4*summaryLevelBits,
-}
-
-// levelLogPages is log2 the maximum number of runtime pages in the address space
-// a summary in the given level represents.
-//
-// The leaf level always represents exactly log2 of 1 chunk's worth of pages.
-var levelLogPages = [summaryLevels]uint{
-	logPallocChunkPages + 4*summaryLevelBits,
-	logPallocChunkPages + 3*summaryLevelBits,
-	logPallocChunkPages + 2*summaryLevelBits,
-	logPallocChunkPages + 1*summaryLevelBits,
-	logPallocChunkPages,
-}
-
-// sysInit performs architecture-dependent initialization of fields
-// in pageAlloc. pageAlloc should be uninitialized except for sysStat
-// if any runtime statistic should be updated.
-func (p *pageAlloc) sysInit() {
-	// Reserve memory for each level. This will get mapped in
-	// as R/W by setArenas.
-	for l, shift := range levelShift {
-		entries := 1 << (heapAddrBits - shift)
-
-		// Reserve b bytes of memory anywhere in the address space.
-		b := alignUp(uintptr(entries)*pallocSumBytes, physPageSize)
-		r := sysReserve(nil, b)
-		if r == nil {
-			throw("failed to reserve page summary memory")
-		}
-
-		// Put this reservation into a slice.
-		sl := notInHeapSlice{(*notInHeap)(r), 0, entries}
-		p.summary[l] = *(*[]pallocSum)(unsafe.Pointer(&sl))
-	}
-}
-
-// sysGrow performs architecture-dependent operations on heap
-// growth for the page allocator, such as mapping in new memory
-// for summaries. It also updates the length of the slices in
-// [.summary.
-//
-// base is the base of the newly-added heap memory and limit is
-// the first address past the end of the newly-added heap memory.
-// Both must be aligned to pallocChunkBytes.
-//
-// The caller must update p.start and p.end after calling sysGrow.
-func (p *pageAlloc) sysGrow(base, limit uintptr) {
-	if base%pallocChunkBytes != 0 || limit%pallocChunkBytes != 0 {
-		print("runtime: base = ", hex(base), ", limit = ", hex(limit), "\n")
-		throw("sysGrow bounds not aligned to pallocChunkBytes")
-	}
-
-	// addrRangeToSummaryRange converts a range of addresses into a range
-	// of summary indices which must be mapped to support those addresses
-	// in the summary range.
-	addrRangeToSummaryRange := func(level int, r addrRange) (int, int) {
-		sumIdxBase, sumIdxLimit := addrsToSummaryRange(level, r.base.addr(), r.limit.addr())
-		return blockAlignSummaryRange(level, sumIdxBase, sumIdxLimit)
-	}
-
-	// summaryRangeToSumAddrRange converts a range of indices in any
-	// level of p.summary into page-aligned addresses which cover that
-	// range of indices.
-	summaryRangeToSumAddrRange := func(level, sumIdxBase, sumIdxLimit int) addrRange {
-		baseOffset := alignDown(uintptr(sumIdxBase)*pallocSumBytes, physPageSize)
-		limitOffset := alignUp(uintptr(sumIdxLimit)*pallocSumBytes, physPageSize)
-		base := unsafe.Pointer(&p.summary[level][0])
-		return addrRange{
-			offAddr{uintptr(add(base, baseOffset))},
-			offAddr{uintptr(add(base, limitOffset))},
-		}
-	}
-
-	// addrRangeToSumAddrRange is a convienience function that converts
-	// an address range r to the address range of the given summary level
-	// that stores the summaries for r.
-	addrRangeToSumAddrRange := func(level int, r addrRange) addrRange {
-		sumIdxBase, sumIdxLimit := addrRangeToSummaryRange(level, r)
-		return summaryRangeToSumAddrRange(level, sumIdxBase, sumIdxLimit)
-	}
-
-	// Find the first inUse index which is strictly greater than base.
-	//
-	// Because this function will never be asked remap the same memory
-	// twice, this index is effectively the index at which we would insert
-	// this new growth, and base will never overlap/be contained within
-	// any existing range.
-	//
-	// This will be used to look at what memory in the summary array is already
-	// mapped before and after this new range.
-	inUseIndex := p.inUse.findSucc(base)
-
-	// Walk up the radix tree and map summaries in as needed.
-	for l := range p.summary {
-		// Figure out what part of the summary array this new address space needs.
-		needIdxBase, needIdxLimit := addrRangeToSummaryRange(l, makeAddrRange(base, limit))
-
-		// Update the summary slices with a new upper-bound. This ensures
-		// we get tight bounds checks on at least the top bound.
-		//
-		// We must do this regardless of whether we map new memory.
-		if needIdxLimit > len(p.summary[l]) {
-			p.summary[l] = p.summary[l][:needIdxLimit]
-		}
-
-		// Compute the needed address range in the summary array for level l.
-		need := summaryRangeToSumAddrRange(l, needIdxBase, needIdxLimit)
-
-		// Prune need down to what needs to be newly mapped. Some parts of it may
-		// already be mapped by what inUse describes due to page alignment requirements
-		// for mapping. prune's invariants are guaranteed by the fact that this
-		// function will never be asked to remap the same memory twice.
-		if inUseIndex > 0 {
-			need = need.subtract(addrRangeToSumAddrRange(l, p.inUse.ranges[inUseIndex-1]))
-		}
-		if inUseIndex < len(p.inUse.ranges) {
-			need = need.subtract(addrRangeToSumAddrRange(l, p.inUse.ranges[inUseIndex]))
-		}
-		// It's possible that after our pruning above, there's nothing new to map.
-		if need.size() == 0 {
-			continue
-		}
-
-		// Map and commit need.
-		sysMap(unsafe.Pointer(need.base.addr()), need.size(), p.sysStat)
-		sysUsed(unsafe.Pointer(need.base.addr()), need.size())
-	}
-}
diff --git a/contrib/go/_std_1.18/src/runtime/mpagecache.go b/contrib/go/_std_1.18/src/runtime/mpagecache.go
deleted file mode 100644
index 7206e2dbdb..0000000000
--- a/contrib/go/_std_1.18/src/runtime/mpagecache.go
+++ /dev/null
@@ -1,177 +0,0 @@
-// Copyright 2019 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"runtime/internal/sys"
-	"unsafe"
-)
-
-const pageCachePages = 8 * unsafe.Sizeof(pageCache{}.cache)
-
-// pageCache represents a per-p cache of pages the allocator can
-// allocate from without a lock. More specifically, it represents
-// a pageCachePages*pageSize chunk of memory with 0 or more free
-// pages in it.
-type pageCache struct {
-	base  uintptr // base address of the chunk
-	cache uint64  // 64-bit bitmap representing free pages (1 means free)
-	scav  uint64  // 64-bit bitmap representing scavenged pages (1 means scavenged)
-}
-
-// empty returns true if the pageCache has any free pages, and false
-// otherwise.
-func (c *pageCache) empty() bool {
-	return c.cache == 0
-}
-
-// alloc allocates npages from the page cache and is the main entry
-// point for allocation.
-//
-// Returns a base address and the amount of scavenged memory in the
-// allocated region in bytes.
-//
-// Returns a base address of zero on failure, in which case the
-// amount of scavenged memory should be ignored.
-func (c *pageCache) alloc(npages uintptr) (uintptr, uintptr) {
-	if c.cache == 0 {
-		return 0, 0
-	}
-	if npages == 1 {
-		i := uintptr(sys.TrailingZeros64(c.cache))
-		scav := (c.scav >> i) & 1
-		c.cache &^= 1 << i // set bit to mark in-use
-		c.scav &^= 1 << i  // clear bit to mark unscavenged
-		return c.base + i*pageSize, uintptr(scav) * pageSize
-	}
-	return c.allocN(npages)
-}
-
-// allocN is a helper which attempts to allocate npages worth of pages
-// from the cache. It represents the general case for allocating from
-// the page cache.
-//
-// Returns a base address and the amount of scavenged memory in the
-// allocated region in bytes.
-func (c *pageCache) allocN(npages uintptr) (uintptr, uintptr) {
-	i := findBitRange64(c.cache, uint(npages))
-	if i >= 64 {
-		return 0, 0
-	}
-	mask := ((uint64(1) << npages) - 1) << i
-	scav := sys.OnesCount64(c.scav & mask)
-	c.cache &^= mask // mark in-use bits
-	c.scav &^= mask  // clear scavenged bits
-	return c.base + uintptr(i*pageSize), uintptr(scav) * pageSize
-}
-
-// flush empties out unallocated free pages in the given cache
-// into s. Then, it clears the cache, such that empty returns
-// true.
-//
-// p.mheapLock must be held.
-//
-// Must run on the system stack because p.mheapLock must be held.
-//
-//go:systemstack
-func (c *pageCache) flush(p *pageAlloc) {
-	assertLockHeld(p.mheapLock)
-
-	if c.empty() {
-		return
-	}
-	ci := chunkIndex(c.base)
-	pi := chunkPageIndex(c.base)
-
-	// This method is called very infrequently, so just do the
-	// slower, safer thing by iterating over each bit individually.
-	for i := uint(0); i < 64; i++ {
-		if c.cache&(1<<i) != 0 {
-			p.chunkOf(ci).free1(pi + i)
-		}
-		if c.scav&(1<<i) != 0 {
-			p.chunkOf(ci).scavenged.setRange(pi+i, 1)
-		}
-	}
-	// Since this is a lot like a free, we need to make sure
-	// we update the searchAddr just like free does.
-	if b := (offAddr{c.base}); b.lessThan(p.searchAddr) {
-		p.searchAddr = b
-	}
-	p.update(c.base, pageCachePages, false, false)
-	*c = pageCache{}
-}
-
-// allocToCache acquires a pageCachePages-aligned chunk of free pages which
-// may not be contiguous, and returns a pageCache structure which owns the
-// chunk.
-//
-// p.mheapLock must be held.
-//
-// Must run on the system stack because p.mheapLock must be held.
-//
-//go:systemstack
-func (p *pageAlloc) allocToCache() pageCache {
-	assertLockHeld(p.mheapLock)
-
-	// If the searchAddr refers to a region which has a higher address than
-	// any known chunk, then we know we're out of memory.
-	if chunkIndex(p.searchAddr.addr()) >= p.end {
-		return pageCache{}
-	}
-	c := pageCache{}
-	ci := chunkIndex(p.searchAddr.addr()) // chunk index
-	var chunk *pallocData
-	if p.summary[len(p.summary)-1][ci] != 0 {
-		// Fast path: there's free pages at or near the searchAddr address.
-		chunk = p.chunkOf(ci)
-		j, _ := chunk.find(1, chunkPageIndex(p.searchAddr.addr()))
-		if j == ^uint(0) {
-			throw("bad summary data")
-		}
-		c = pageCache{
-			base:  chunkBase(ci) + alignDown(uintptr(j), 64)*pageSize,
-			cache: ^chunk.pages64(j),
-			scav:  chunk.scavenged.block64(j),
-		}
-	} else {
-		// Slow path: the searchAddr address had nothing there, so go find
-		// the first free page the slow way.
-		addr, _ := p.find(1)
-		if addr == 0 {
-			// We failed to find adequate free space, so mark the searchAddr as OoM
-			// and return an empty pageCache.
-			p.searchAddr = maxSearchAddr
-			return pageCache{}
-		}
-		ci := chunkIndex(addr)
-		chunk = p.chunkOf(ci)
-		c = pageCache{
-			base:  alignDown(addr, 64*pageSize),
-			cache: ^chunk.pages64(chunkPageIndex(addr)),
-			scav:  chunk.scavenged.block64(chunkPageIndex(addr)),
-		}
-	}
-
-	// Set the page bits as allocated and clear the scavenged bits, but
-	// be careful to only set and clear the relevant bits.
-	cpi := chunkPageIndex(c.base)
-	chunk.allocPages64(cpi, c.cache)
-	chunk.scavenged.clearBlock64(cpi, c.cache&c.scav /* free and scavenged */)
-
-	// Update as an allocation, but note that it's not contiguous.
-	p.update(c.base, pageCachePages, false, true)
-
-	// Set the search address to the last page represented by the cache.
-	// Since all of the pages in this block are going to the cache, and we
-	// searched for the first free page, we can confidently start at the
-	// next page.
-	//
-	// However, p.searchAddr is not allowed to point into unmapped heap memory
-	// unless it is maxSearchAddr, so make it the last page as opposed to
-	// the page after.
-	p.searchAddr = offAddr{c.base + pageSize*(pageCachePages-1)}
-	return c
-}
diff --git a/contrib/go/_std_1.18/src/runtime/mprof.go b/contrib/go/_std_1.18/src/runtime/mprof.go
deleted file mode 100644
index 569c17f0a7..0000000000
--- a/contrib/go/_std_1.18/src/runtime/mprof.go
+++ /dev/null
@@ -1,937 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Malloc profiling.
-// Patterned after tcmalloc's algorithms; shorter code.
-
-package runtime
-
-import (
-	"internal/abi"
-	"runtime/internal/atomic"
-	"unsafe"
-)
-
-// NOTE(rsc): Everything here could use cas if contention became an issue.
-var proflock mutex
-
-// All memory allocations are local and do not escape outside of the profiler.
-// The profiler is forbidden from referring to garbage-collected memory.
-
-const (
-	// profile types
-	memProfile bucketType = 1 + iota
-	blockProfile
-	mutexProfile
-
-	// size of bucket hash table
-	buckHashSize = 179999
-
-	// max depth of stack to record in bucket
-	maxStack = 32
-)
-
-type bucketType int
-
-// A bucket holds per-call-stack profiling information.
-// The representation is a bit sleazy, inherited from C.
-// This struct defines the bucket header. It is followed in
-// memory by the stack words and then the actual record
-// data, either a memRecord or a blockRecord.
-//
-// Per-call-stack profiling information.
-// Lookup by hashing call stack into a linked-list hash table.
-//
-// No heap pointers.
-//
-//go:notinheap
-type bucket struct {
-	next    *bucket
-	allnext *bucket
-	typ     bucketType // memBucket or blockBucket (includes mutexProfile)
-	hash    uintptr
-	size    uintptr
-	nstk    uintptr
-}
-
-// A memRecord is the bucket data for a bucket of type memProfile,
-// part of the memory profile.
-type memRecord struct {
-	// The following complex 3-stage scheme of stats accumulation
-	// is required to obtain a consistent picture of mallocs and frees
-	// for some point in time.
-	// The problem is that mallocs come in real time, while frees
-	// come only after a GC during concurrent sweeping. So if we would
-	// naively count them, we would get a skew toward mallocs.
-	//
-	// Hence, we delay information to get consistent snapshots as
-	// of mark termination. Allocations count toward the next mark
-	// termination's snapshot, while sweep frees count toward the
-	// previous mark termination's snapshot:
-	//
-	//              MT          MT          MT          MT
-	//             .·|         .·|         .·|         .·|
-	//          .·˙  |      .·˙  |      .·˙  |      .·˙  |
-	//       .·˙     |   .·˙     |   .·˙     |   .·˙     |
-	//    .·˙        |.·˙        |.·˙        |.·˙        |
-	//
-	//       alloc → ▲ ← free
-	//               ┠┅┅┅┅┅┅┅┅┅┅┅P
-	//       C+2     →    C+1    →  C
-	//
-	//                   alloc → ▲ ← free
-	//                           ┠┅┅┅┅┅┅┅┅┅┅┅P
-	//                   C+2     →    C+1    →  C
-	//
-	// Since we can't publish a consistent snapshot until all of
-	// the sweep frees are accounted for, we wait until the next
-	// mark termination ("MT" above) to publish the previous mark
-	// termination's snapshot ("P" above). To do this, allocation
-	// and free events are accounted to *future* heap profile
-	// cycles ("C+n" above) and we only publish a cycle once all
-	// of the events from that cycle must be done. Specifically:
-	//
-	// Mallocs are accounted to cycle C+2.
-	// Explicit frees are accounted to cycle C+2.
-	// GC frees (done during sweeping) are accounted to cycle C+1.
-	//
-	// After mark termination, we increment the global heap
-	// profile cycle counter and accumulate the stats from cycle C
-	// into the active profile.
-
-	// active is the currently published profile. A profiling
-	// cycle can be accumulated into active once its complete.
-	active memRecordCycle
-
-	// future records the profile events we're counting for cycles
-	// that have not yet been published. This is ring buffer
-	// indexed by the global heap profile cycle C and stores
-	// cycles C, C+1, and C+2. Unlike active, these counts are
-	// only for a single cycle; they are not cumulative across
-	// cycles.
-	//
-	// We store cycle C here because there's a window between when
-	// C becomes the active cycle and when we've flushed it to
-	// active.
-	future [3]memRecordCycle
-}
-
-// memRecordCycle
-type memRecordCycle struct {
-	allocs, frees           uintptr
-	alloc_bytes, free_bytes uintptr
-}
-
-// add accumulates b into a. It does not zero b.
-func (a *memRecordCycle) add(b *memRecordCycle) {
-	a.allocs += b.allocs
-	a.frees += b.frees
-	a.alloc_bytes += b.alloc_bytes
-	a.free_bytes += b.free_bytes
-}
-
-// A blockRecord is the bucket data for a bucket of type blockProfile,
-// which is used in blocking and mutex profiles.
-type blockRecord struct {
-	count  float64
-	cycles int64
-}
-
-var (
-	mbuckets  *bucket // memory profile buckets
-	bbuckets  *bucket // blocking profile buckets
-	xbuckets  *bucket // mutex profile buckets
-	buckhash  *[buckHashSize]*bucket
-	bucketmem uintptr
-
-	mProf struct {
-		// All fields in mProf are protected by proflock.
-
-		// cycle is the global heap profile cycle. This wraps
-		// at mProfCycleWrap.
-		cycle uint32
-		// flushed indicates that future[cycle] in all buckets
-		// has been flushed to the active profile.
-		flushed bool
-	}
-)
-
-const mProfCycleWrap = uint32(len(memRecord{}.future)) * (2 << 24)
-
-// newBucket allocates a bucket with the given type and number of stack entries.
-func newBucket(typ bucketType, nstk int) *bucket {
-	size := unsafe.Sizeof(bucket{}) + uintptr(nstk)*unsafe.Sizeof(uintptr(0))
-	switch typ {
-	default:
-		throw("invalid profile bucket type")
-	case memProfile:
-		size += unsafe.Sizeof(memRecord{})
-	case blockProfile, mutexProfile:
-		size += unsafe.Sizeof(blockRecord{})
-	}
-
-	b := (*bucket)(persistentalloc(size, 0, &memstats.buckhash_sys))
-	bucketmem += size
-	b.typ = typ
-	b.nstk = uintptr(nstk)
-	return b
-}
-
-// stk returns the slice in b holding the stack.
-func (b *bucket) stk() []uintptr {
-	stk := (*[maxStack]uintptr)(add(unsafe.Pointer(b), unsafe.Sizeof(*b)))
-	return stk[:b.nstk:b.nstk]
-}
-
-// mp returns the memRecord associated with the memProfile bucket b.
-func (b *bucket) mp() *memRecord {
-	if b.typ != memProfile {
-		throw("bad use of bucket.mp")
-	}
-	data := add(unsafe.Pointer(b), unsafe.Sizeof(*b)+b.nstk*unsafe.Sizeof(uintptr(0)))
-	return (*memRecord)(data)
-}
-
-// bp returns the blockRecord associated with the blockProfile bucket b.
-func (b *bucket) bp() *blockRecord {
-	if b.typ != blockProfile && b.typ != mutexProfile {
-		throw("bad use of bucket.bp")
-	}
-	data := add(unsafe.Pointer(b), unsafe.Sizeof(*b)+b.nstk*unsafe.Sizeof(uintptr(0)))
-	return (*blockRecord)(data)
-}
-
-// Return the bucket for stk[0:nstk], allocating new bucket if needed.
-func stkbucket(typ bucketType, size uintptr, stk []uintptr, alloc bool) *bucket {
-	if buckhash == nil {
-		buckhash = (*[buckHashSize]*bucket)(sysAlloc(unsafe.Sizeof(*buckhash), &memstats.buckhash_sys))
-		if buckhash == nil {
-			throw("runtime: cannot allocate memory")
-		}
-	}
-
-	// Hash stack.
-	var h uintptr
-	for _, pc := range stk {
-		h += pc
-		h += h << 10
-		h ^= h >> 6
-	}
-	// hash in size
-	h += size
-	h += h << 10
-	h ^= h >> 6
-	// finalize
-	h += h << 3
-	h ^= h >> 11
-
-	i := int(h % buckHashSize)
-	for b := buckhash[i]; b != nil; b = b.next {
-		if b.typ == typ && b.hash == h && b.size == size && eqslice(b.stk(), stk) {
-			return b
-		}
-	}
-
-	if !alloc {
-		return nil
-	}
-
-	// Create new bucket.
-	b := newBucket(typ, len(stk))
-	copy(b.stk(), stk)
-	b.hash = h
-	b.size = size
-	b.next = buckhash[i]
-	buckhash[i] = b
-	if typ == memProfile {
-		b.allnext = mbuckets
-		mbuckets = b
-	} else if typ == mutexProfile {
-		b.allnext = xbuckets
-		xbuckets = b
-	} else {
-		b.allnext = bbuckets
-		bbuckets = b
-	}
-	return b
-}
-
-func eqslice(x, y []uintptr) bool {
-	if len(x) != len(y) {
-		return false
-	}
-	for i, xi := range x {
-		if xi != y[i] {
-			return false
-		}
-	}
-	return true
-}
-
-// mProf_NextCycle publishes the next heap profile cycle and creates a
-// fresh heap profile cycle. This operation is fast and can be done
-// during STW. The caller must call mProf_Flush before calling
-// mProf_NextCycle again.
-//
-// This is called by mark termination during STW so allocations and
-// frees after the world is started again count towards a new heap
-// profiling cycle.
-func mProf_NextCycle() {
-	lock(&proflock)
-	// We explicitly wrap mProf.cycle rather than depending on
-	// uint wraparound because the memRecord.future ring does not
-	// itself wrap at a power of two.
-	mProf.cycle = (mProf.cycle + 1) % mProfCycleWrap
-	mProf.flushed = false
-	unlock(&proflock)
-}
-
-// mProf_Flush flushes the events from the current heap profiling
-// cycle into the active profile. After this it is safe to start a new
-// heap profiling cycle with mProf_NextCycle.
-//
-// This is called by GC after mark termination starts the world. In
-// contrast with mProf_NextCycle, this is somewhat expensive, but safe
-// to do concurrently.
-func mProf_Flush() {
-	lock(&proflock)
-	if !mProf.flushed {
-		mProf_FlushLocked()
-		mProf.flushed = true
-	}
-	unlock(&proflock)
-}
-
-func mProf_FlushLocked() {
-	c := mProf.cycle
-	for b := mbuckets; b != nil; b = b.allnext {
-		mp := b.mp()
-
-		// Flush cycle C into the published profile and clear
-		// it for reuse.
-		mpc := &mp.future[c%uint32(len(mp.future))]
-		mp.active.add(mpc)
-		*mpc = memRecordCycle{}
-	}
-}
-
-// mProf_PostSweep records that all sweep frees for this GC cycle have
-// completed. This has the effect of publishing the heap profile
-// snapshot as of the last mark termination without advancing the heap
-// profile cycle.
-func mProf_PostSweep() {
-	lock(&proflock)
-	// Flush cycle C+1 to the active profile so everything as of
-	// the last mark termination becomes visible. *Don't* advance
-	// the cycle, since we're still accumulating allocs in cycle
-	// C+2, which have to become C+1 in the next mark termination
-	// and so on.
-	c := mProf.cycle
-	for b := mbuckets; b != nil; b = b.allnext {
-		mp := b.mp()
-		mpc := &mp.future[(c+1)%uint32(len(mp.future))]
-		mp.active.add(mpc)
-		*mpc = memRecordCycle{}
-	}
-	unlock(&proflock)
-}
-
-// Called by malloc to record a profiled block.
-func mProf_Malloc(p unsafe.Pointer, size uintptr) {
-	var stk [maxStack]uintptr
-	nstk := callers(4, stk[:])
-	lock(&proflock)
-	b := stkbucket(memProfile, size, stk[:nstk], true)
-	c := mProf.cycle
-	mp := b.mp()
-	mpc := &mp.future[(c+2)%uint32(len(mp.future))]
-	mpc.allocs++
-	mpc.alloc_bytes += size
-	unlock(&proflock)
-
-	// Setprofilebucket locks a bunch of other mutexes, so we call it outside of proflock.
-	// This reduces potential contention and chances of deadlocks.
-	// Since the object must be alive during call to mProf_Malloc,
-	// it's fine to do this non-atomically.
-	systemstack(func() {
-		setprofilebucket(p, b)
-	})
-}
-
-// Called when freeing a profiled block.
-func mProf_Free(b *bucket, size uintptr) {
-	lock(&proflock)
-	c := mProf.cycle
-	mp := b.mp()
-	mpc := &mp.future[(c+1)%uint32(len(mp.future))]
-	mpc.frees++
-	mpc.free_bytes += size
-	unlock(&proflock)
-}
-
-var blockprofilerate uint64 // in CPU ticks
-
-// SetBlockProfileRate controls the fraction of goroutine blocking events
-// that are reported in the blocking profile. The profiler aims to sample
-// an average of one blocking event per rate nanoseconds spent blocked.
-//
-// To include every blocking event in the profile, pass rate = 1.
-// To turn off profiling entirely, pass rate <= 0.
-func SetBlockProfileRate(rate int) {
-	var r int64
-	if rate <= 0 {
-		r = 0 // disable profiling
-	} else if rate == 1 {
-		r = 1 // profile everything
-	} else {
-		// convert ns to cycles, use float64 to prevent overflow during multiplication
-		r = int64(float64(rate) * float64(tickspersecond()) / (1000 * 1000 * 1000))
-		if r == 0 {
-			r = 1
-		}
-	}
-
-	atomic.Store64(&blockprofilerate, uint64(r))
-}
-
-func blockevent(cycles int64, skip int) {
-	if cycles <= 0 {
-		cycles = 1
-	}
-
-	rate := int64(atomic.Load64(&blockprofilerate))
-	if blocksampled(cycles, rate) {
-		saveblockevent(cycles, rate, skip+1, blockProfile)
-	}
-}
-
-// blocksampled returns true for all events where cycles >= rate. Shorter
-// events have a cycles/rate random chance of returning true.
-func blocksampled(cycles, rate int64) bool {
-	if rate <= 0 || (rate > cycles && int64(fastrand())%rate > cycles) {
-		return false
-	}
-	return true
-}
-
-func saveblockevent(cycles, rate int64, skip int, which bucketType) {
-	gp := getg()
-	var nstk int
-	var stk [maxStack]uintptr
-	if gp.m.curg == nil || gp.m.curg == gp {
-		nstk = callers(skip, stk[:])
-	} else {
-		nstk = gcallers(gp.m.curg, skip, stk[:])
-	}
-	lock(&proflock)
-	b := stkbucket(which, 0, stk[:nstk], true)
-
-	if which == blockProfile && cycles < rate {
-		// Remove sampling bias, see discussion on http://golang.org/cl/299991.
-		b.bp().count += float64(rate) / float64(cycles)
-		b.bp().cycles += rate
-	} else {
-		b.bp().count++
-		b.bp().cycles += cycles
-	}
-	unlock(&proflock)
-}
-
-var mutexprofilerate uint64 // fraction sampled
-
-// SetMutexProfileFraction controls the fraction of mutex contention events
-// that are reported in the mutex profile. On average 1/rate events are
-// reported. The previous rate is returned.
-//
-// To turn off profiling entirely, pass rate 0.
-// To just read the current rate, pass rate < 0.
-// (For n>1 the details of sampling may change.)
-func SetMutexProfileFraction(rate int) int {
-	if rate < 0 {
-		return int(mutexprofilerate)
-	}
-	old := mutexprofilerate
-	atomic.Store64(&mutexprofilerate, uint64(rate))
-	return int(old)
-}
-
-//go:linkname mutexevent sync.event
-func mutexevent(cycles int64, skip int) {
-	if cycles < 0 {
-		cycles = 0
-	}
-	rate := int64(atomic.Load64(&mutexprofilerate))
-	// TODO(pjw): measure impact of always calling fastrand vs using something
-	// like malloc.go:nextSample()
-	if rate > 0 && int64(fastrand())%rate == 0 {
-		saveblockevent(cycles, rate, skip+1, mutexProfile)
-	}
-}
-
-// Go interface to profile data.
-
-// A StackRecord describes a single execution stack.
-type StackRecord struct {
-	Stack0 [32]uintptr // stack trace for this record; ends at first 0 entry
-}
-
-// Stack returns the stack trace associated with the record,
-// a prefix of r.Stack0.
-func (r *StackRecord) Stack() []uintptr {
-	for i, v := range r.Stack0 {
-		if v == 0 {
-			return r.Stack0[0:i]
-		}
-	}
-	return r.Stack0[0:]
-}
-
-// MemProfileRate controls the fraction of memory allocations
-// that are recorded and reported in the memory profile.
-// The profiler aims to sample an average of
-// one allocation per MemProfileRate bytes allocated.
-//
-// To include every allocated block in the profile, set MemProfileRate to 1.
-// To turn off profiling entirely, set MemProfileRate to 0.
-//
-// The tools that process the memory profiles assume that the
-// profile rate is constant across the lifetime of the program
-// and equal to the current value. Programs that change the
-// memory profiling rate should do so just once, as early as
-// possible in the execution of the program (for example,
-// at the beginning of main).
-var MemProfileRate int = defaultMemProfileRate(512 * 1024)
-
-// defaultMemProfileRate returns 0 if disableMemoryProfiling is set.
-// It exists primarily for the godoc rendering of MemProfileRate
-// above.
-func defaultMemProfileRate(v int) int {
-	if disableMemoryProfiling {
-		return 0
-	}
-	return v
-}
-
-// disableMemoryProfiling is set by the linker if runtime.MemProfile
-// is not used and the link type guarantees nobody else could use it
-// elsewhere.
-var disableMemoryProfiling bool
-
-// A MemProfileRecord describes the live objects allocated
-// by a particular call sequence (stack trace).
-type MemProfileRecord struct {
-	AllocBytes, FreeBytes     int64       // number of bytes allocated, freed
-	AllocObjects, FreeObjects int64       // number of objects allocated, freed
-	Stack0                    [32]uintptr // stack trace for this record; ends at first 0 entry
-}
-
-// InUseBytes returns the number of bytes in use (AllocBytes - FreeBytes).
-func (r *MemProfileRecord) InUseBytes() int64 { return r.AllocBytes - r.FreeBytes }
-
-// InUseObjects returns the number of objects in use (AllocObjects - FreeObjects).
-func (r *MemProfileRecord) InUseObjects() int64 {
-	return r.AllocObjects - r.FreeObjects
-}
-
-// Stack returns the stack trace associated with the record,
-// a prefix of r.Stack0.
-func (r *MemProfileRecord) Stack() []uintptr {
-	for i, v := range r.Stack0 {
-		if v == 0 {
-			return r.Stack0[0:i]
-		}
-	}
-	return r.Stack0[0:]
-}
-
-// MemProfile returns a profile of memory allocated and freed per allocation
-// site.
-//
-// MemProfile returns n, the number of records in the current memory profile.
-// If len(p) >= n, MemProfile copies the profile into p and returns n, true.
-// If len(p) < n, MemProfile does not change p and returns n, false.
-//
-// If inuseZero is true, the profile includes allocation records
-// where r.AllocBytes > 0 but r.AllocBytes == r.FreeBytes.
-// These are sites where memory was allocated, but it has all
-// been released back to the runtime.
-//
-// The returned profile may be up to two garbage collection cycles old.
-// This is to avoid skewing the profile toward allocations; because
-// allocations happen in real time but frees are delayed until the garbage
-// collector performs sweeping, the profile only accounts for allocations
-// that have had a chance to be freed by the garbage collector.
-//
-// Most clients should use the runtime/pprof package or
-// the testing package's -test.memprofile flag instead
-// of calling MemProfile directly.
-func MemProfile(p []MemProfileRecord, inuseZero bool) (n int, ok bool) {
-	lock(&proflock)
-	// If we're between mProf_NextCycle and mProf_Flush, take care
-	// of flushing to the active profile so we only have to look
-	// at the active profile below.
-	mProf_FlushLocked()
-	clear := true
-	for b := mbuckets; b != nil; b = b.allnext {
-		mp := b.mp()
-		if inuseZero || mp.active.alloc_bytes != mp.active.free_bytes {
-			n++
-		}
-		if mp.active.allocs != 0 || mp.active.frees != 0 {
-			clear = false
-		}
-	}
-	if clear {
-		// Absolutely no data, suggesting that a garbage collection
-		// has not yet happened. In order to allow profiling when
-		// garbage collection is disabled from the beginning of execution,
-		// accumulate all of the cycles, and recount buckets.
-		n = 0
-		for b := mbuckets; b != nil; b = b.allnext {
-			mp := b.mp()
-			for c := range mp.future {
-				mp.active.add(&mp.future[c])
-				mp.future[c] = memRecordCycle{}
-			}
-			if inuseZero || mp.active.alloc_bytes != mp.active.free_bytes {
-				n++
-			}
-		}
-	}
-	if n <= len(p) {
-		ok = true
-		idx := 0
-		for b := mbuckets; b != nil; b = b.allnext {
-			mp := b.mp()
-			if inuseZero || mp.active.alloc_bytes != mp.active.free_bytes {
-				record(&p[idx], b)
-				idx++
-			}
-		}
-	}
-	unlock(&proflock)
-	return
-}
-
-// Write b's data to r.
-func record(r *MemProfileRecord, b *bucket) {
-	mp := b.mp()
-	r.AllocBytes = int64(mp.active.alloc_bytes)
-	r.FreeBytes = int64(mp.active.free_bytes)
-	r.AllocObjects = int64(mp.active.allocs)
-	r.FreeObjects = int64(mp.active.frees)
-	if raceenabled {
-		racewriterangepc(unsafe.Pointer(&r.Stack0[0]), unsafe.Sizeof(r.Stack0), getcallerpc(), abi.FuncPCABIInternal(MemProfile))
-	}
-	if msanenabled {
-		msanwrite(unsafe.Pointer(&r.Stack0[0]), unsafe.Sizeof(r.Stack0))
-	}
-	if asanenabled {
-		asanwrite(unsafe.Pointer(&r.Stack0[0]), unsafe.Sizeof(r.Stack0))
-	}
-	copy(r.Stack0[:], b.stk())
-	for i := int(b.nstk); i < len(r.Stack0); i++ {
-		r.Stack0[i] = 0
-	}
-}
-
-func iterate_memprof(fn func(*bucket, uintptr, *uintptr, uintptr, uintptr, uintptr)) {
-	lock(&proflock)
-	for b := mbuckets; b != nil; b = b.allnext {
-		mp := b.mp()
-		fn(b, b.nstk, &b.stk()[0], b.size, mp.active.allocs, mp.active.frees)
-	}
-	unlock(&proflock)
-}
-
-// BlockProfileRecord describes blocking events originated
-// at a particular call sequence (stack trace).
-type BlockProfileRecord struct {
-	Count  int64
-	Cycles int64
-	StackRecord
-}
-
-// BlockProfile returns n, the number of records in the current blocking profile.
-// If len(p) >= n, BlockProfile copies the profile into p and returns n, true.
-// If len(p) < n, BlockProfile does not change p and returns n, false.
-//
-// Most clients should use the runtime/pprof package or
-// the testing package's -test.blockprofile flag instead
-// of calling BlockProfile directly.
-func BlockProfile(p []BlockProfileRecord) (n int, ok bool) {
-	lock(&proflock)
-	for b := bbuckets; b != nil; b = b.allnext {
-		n++
-	}
-	if n <= len(p) {
-		ok = true
-		for b := bbuckets; b != nil; b = b.allnext {
-			bp := b.bp()
-			r := &p[0]
-			r.Count = int64(bp.count)
-			// Prevent callers from having to worry about division by zero errors.
-			// See discussion on http://golang.org/cl/299991.
-			if r.Count == 0 {
-				r.Count = 1
-			}
-			r.Cycles = bp.cycles
-			if raceenabled {
-				racewriterangepc(unsafe.Pointer(&r.Stack0[0]), unsafe.Sizeof(r.Stack0), getcallerpc(), abi.FuncPCABIInternal(BlockProfile))
-			}
-			if msanenabled {
-				msanwrite(unsafe.Pointer(&r.Stack0[0]), unsafe.Sizeof(r.Stack0))
-			}
-			if asanenabled {
-				asanwrite(unsafe.Pointer(&r.Stack0[0]), unsafe.Sizeof(r.Stack0))
-			}
-			i := copy(r.Stack0[:], b.stk())
-			for ; i < len(r.Stack0); i++ {
-				r.Stack0[i] = 0
-			}
-			p = p[1:]
-		}
-	}
-	unlock(&proflock)
-	return
-}
-
-// MutexProfile returns n, the number of records in the current mutex profile.
-// If len(p) >= n, MutexProfile copies the profile into p and returns n, true.
-// Otherwise, MutexProfile does not change p, and returns n, false.
-//
-// Most clients should use the runtime/pprof package
-// instead of calling MutexProfile directly.
-func MutexProfile(p []BlockProfileRecord) (n int, ok bool) {
-	lock(&proflock)
-	for b := xbuckets; b != nil; b = b.allnext {
-		n++
-	}
-	if n <= len(p) {
-		ok = true
-		for b := xbuckets; b != nil; b = b.allnext {
-			bp := b.bp()
-			r := &p[0]
-			r.Count = int64(bp.count)
-			r.Cycles = bp.cycles
-			i := copy(r.Stack0[:], b.stk())
-			for ; i < len(r.Stack0); i++ {
-				r.Stack0[i] = 0
-			}
-			p = p[1:]
-		}
-	}
-	unlock(&proflock)
-	return
-}
-
-// ThreadCreateProfile returns n, the number of records in the thread creation profile.
-// If len(p) >= n, ThreadCreateProfile copies the profile into p and returns n, true.
-// If len(p) < n, ThreadCreateProfile does not change p and returns n, false.
-//
-// Most clients should use the runtime/pprof package instead
-// of calling ThreadCreateProfile directly.
-func ThreadCreateProfile(p []StackRecord) (n int, ok bool) {
-	first := (*m)(atomic.Loadp(unsafe.Pointer(&allm)))
-	for mp := first; mp != nil; mp = mp.alllink {
-		n++
-	}
-	if n <= len(p) {
-		ok = true
-		i := 0
-		for mp := first; mp != nil; mp = mp.alllink {
-			p[i].Stack0 = mp.createstack
-			i++
-		}
-	}
-	return
-}
-
-//go:linkname runtime_goroutineProfileWithLabels runtime/pprof.runtime_goroutineProfileWithLabels
-func runtime_goroutineProfileWithLabels(p []StackRecord, labels []unsafe.Pointer) (n int, ok bool) {
-	return goroutineProfileWithLabels(p, labels)
-}
-
-// labels may be nil. If labels is non-nil, it must have the same length as p.
-func goroutineProfileWithLabels(p []StackRecord, labels []unsafe.Pointer) (n int, ok bool) {
-	if labels != nil && len(labels) != len(p) {
-		labels = nil
-	}
-	gp := getg()
-
-	isOK := func(gp1 *g) bool {
-		// Checking isSystemGoroutine here makes GoroutineProfile
-		// consistent with both NumGoroutine and Stack.
-		return gp1 != gp && readgstatus(gp1) != _Gdead && !isSystemGoroutine(gp1, false)
-	}
-
-	stopTheWorld("profile")
-
-	// World is stopped, no locking required.
-	n = 1
-	forEachGRace(func(gp1 *g) {
-		if isOK(gp1) {
-			n++
-		}
-	})
-
-	if n <= len(p) {
-		ok = true
-		r, lbl := p, labels
-
-		// Save current goroutine.
-		sp := getcallersp()
-		pc := getcallerpc()
-		systemstack(func() {
-			saveg(pc, sp, gp, &r[0])
-		})
-		r = r[1:]
-
-		// If we have a place to put our goroutine labelmap, insert it there.
-		if labels != nil {
-			lbl[0] = gp.labels
-			lbl = lbl[1:]
-		}
-
-		// Save other goroutines.
-		forEachGRace(func(gp1 *g) {
-			if !isOK(gp1) {
-				return
-			}
-
-			if len(r) == 0 {
-				// Should be impossible, but better to return a
-				// truncated profile than to crash the entire process.
-				return
-			}
-			// saveg calls gentraceback, which may call cgo traceback functions.
-			// The world is stopped, so it cannot use cgocall (which will be
-			// blocked at exitsyscall). Do it on the system stack so it won't
-			// call into the schedular (see traceback.go:cgoContextPCs).
-			systemstack(func() { saveg(^uintptr(0), ^uintptr(0), gp1, &r[0]) })
-			if labels != nil {
-				lbl[0] = gp1.labels
-				lbl = lbl[1:]
-			}
-			r = r[1:]
-		})
-	}
-
-	startTheWorld()
-	return n, ok
-}
-
-// GoroutineProfile returns n, the number of records in the active goroutine stack profile.
-// If len(p) >= n, GoroutineProfile copies the profile into p and returns n, true.
-// If len(p) < n, GoroutineProfile does not change p and returns n, false.
-//
-// Most clients should use the runtime/pprof package instead
-// of calling GoroutineProfile directly.
-func GoroutineProfile(p []StackRecord) (n int, ok bool) {
-
-	return goroutineProfileWithLabels(p, nil)
-}
-
-func saveg(pc, sp uintptr, gp *g, r *StackRecord) {
-	n := gentraceback(pc, sp, 0, gp, 0, &r.Stack0[0], len(r.Stack0), nil, nil, 0)
-	if n < len(r.Stack0) {
-		r.Stack0[n] = 0
-	}
-}
-
-// Stack formats a stack trace of the calling goroutine into buf
-// and returns the number of bytes written to buf.
-// If all is true, Stack formats stack traces of all other goroutines
-// into buf after the trace for the current goroutine.
-func Stack(buf []byte, all bool) int {
-	if all {
-		stopTheWorld("stack trace")
-	}
-
-	n := 0
-	if len(buf) > 0 {
-		gp := getg()
-		sp := getcallersp()
-		pc := getcallerpc()
-		systemstack(func() {
-			g0 := getg()
-			// Force traceback=1 to override GOTRACEBACK setting,
-			// so that Stack's results are consistent.
-			// GOTRACEBACK is only about crash dumps.
-			g0.m.traceback = 1
-			g0.writebuf = buf[0:0:len(buf)]
-			goroutineheader(gp)
-			traceback(pc, sp, 0, gp)
-			if all {
-				tracebackothers(gp)
-			}
-			g0.m.traceback = 0
-			n = len(g0.writebuf)
-			g0.writebuf = nil
-		})
-	}
-
-	if all {
-		startTheWorld()
-	}
-	return n
-}
-
-// Tracing of alloc/free/gc.
-
-var tracelock mutex
-
-func tracealloc(p unsafe.Pointer, size uintptr, typ *_type) {
-	lock(&tracelock)
-	gp := getg()
-	gp.m.traceback = 2
-	if typ == nil {
-		print("tracealloc(", p, ", ", hex(size), ")\n")
-	} else {
-		print("tracealloc(", p, ", ", hex(size), ", ", typ.string(), ")\n")
-	}
-	if gp.m.curg == nil || gp == gp.m.curg {
-		goroutineheader(gp)
-		pc := getcallerpc()
-		sp := getcallersp()
-		systemstack(func() {
-			traceback(pc, sp, 0, gp)
-		})
-	} else {
-		goroutineheader(gp.m.curg)
-		traceback(^uintptr(0), ^uintptr(0), 0, gp.m.curg)
-	}
-	print("\n")
-	gp.m.traceback = 0
-	unlock(&tracelock)
-}
-
-func tracefree(p unsafe.Pointer, size uintptr) {
-	lock(&tracelock)
-	gp := getg()
-	gp.m.traceback = 2
-	print("tracefree(", p, ", ", hex(size), ")\n")
-	goroutineheader(gp)
-	pc := getcallerpc()
-	sp := getcallersp()
-	systemstack(func() {
-		traceback(pc, sp, 0, gp)
-	})
-	print("\n")
-	gp.m.traceback = 0
-	unlock(&tracelock)
-}
-
-func tracegc() {
-	lock(&tracelock)
-	gp := getg()
-	gp.m.traceback = 2
-	print("tracegc()\n")
-	// running on m->g0 stack; show all non-g0 goroutines
-	tracebackothers(gp)
-	print("end tracegc\n")
-	print("\n")
-	gp.m.traceback = 0
-	unlock(&tracelock)
-}
diff --git a/contrib/go/_std_1.18/src/runtime/mranges.go b/contrib/go/_std_1.18/src/runtime/mranges.go
deleted file mode 100644
index e0be1e134e..0000000000
--- a/contrib/go/_std_1.18/src/runtime/mranges.go
+++ /dev/null
@@ -1,372 +0,0 @@
-// Copyright 2019 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Address range data structure.
-//
-// This file contains an implementation of a data structure which
-// manages ordered address ranges.
-
-package runtime
-
-import (
-	"internal/goarch"
-	"unsafe"
-)
-
-// addrRange represents a region of address space.
-//
-// An addrRange must never span a gap in the address space.
-type addrRange struct {
-	// base and limit together represent the region of address space
-	// [base, limit). That is, base is inclusive, limit is exclusive.
-	// These are address over an offset view of the address space on
-	// platforms with a segmented address space, that is, on platforms
-	// where arenaBaseOffset != 0.
-	base, limit offAddr
-}
-
-// makeAddrRange creates a new address range from two virtual addresses.
-//
-// Throws if the base and limit are not in the same memory segment.
-func makeAddrRange(base, limit uintptr) addrRange {
-	r := addrRange{offAddr{base}, offAddr{limit}}
-	if (base-arenaBaseOffset >= base) != (limit-arenaBaseOffset >= limit) {
-		throw("addr range base and limit are not in the same memory segment")
-	}
-	return r
-}
-
-// size returns the size of the range represented in bytes.
-func (a addrRange) size() uintptr {
-	if !a.base.lessThan(a.limit) {
-		return 0
-	}
-	// Subtraction is safe because limit and base must be in the same
-	// segment of the address space.
-	return a.limit.diff(a.base)
-}
-
-// contains returns whether or not the range contains a given address.
-func (a addrRange) contains(addr uintptr) bool {
-	return a.base.lessEqual(offAddr{addr}) && (offAddr{addr}).lessThan(a.limit)
-}
-
-// subtract takes the addrRange toPrune and cuts out any overlap with
-// from, then returns the new range. subtract assumes that a and b
-// either don't overlap at all, only overlap on one side, or are equal.
-// If b is strictly contained in a, thus forcing a split, it will throw.
-func (a addrRange) subtract(b addrRange) addrRange {
-	if b.base.lessEqual(a.base) && a.limit.lessEqual(b.limit) {
-		return addrRange{}
-	} else if a.base.lessThan(b.base) && b.limit.lessThan(a.limit) {
-		throw("bad prune")
-	} else if b.limit.lessThan(a.limit) && a.base.lessThan(b.limit) {
-		a.base = b.limit
-	} else if a.base.lessThan(b.base) && b.base.lessThan(a.limit) {
-		a.limit = b.base
-	}
-	return a
-}
-
-// removeGreaterEqual removes all addresses in a greater than or equal
-// to addr and returns the new range.
-func (a addrRange) removeGreaterEqual(addr uintptr) addrRange {
-	if (offAddr{addr}).lessEqual(a.base) {
-		return addrRange{}
-	}
-	if a.limit.lessEqual(offAddr{addr}) {
-		return a
-	}
-	return makeAddrRange(a.base.addr(), addr)
-}
-
-var (
-	// minOffAddr is the minimum address in the offset space, and
-	// it corresponds to the virtual address arenaBaseOffset.
-	minOffAddr = offAddr{arenaBaseOffset}
-
-	// maxOffAddr is the maximum address in the offset address
-	// space. It corresponds to the highest virtual address representable
-	// by the page alloc chunk and heap arena maps.
-	maxOffAddr = offAddr{(((1 << heapAddrBits) - 1) + arenaBaseOffset) & uintptrMask}
-)
-
-// offAddr represents an address in a contiguous view
-// of the address space on systems where the address space is
-// segmented. On other systems, it's just a normal address.
-type offAddr struct {
-	// a is just the virtual address, but should never be used
-	// directly. Call addr() to get this value instead.
-	a uintptr
-}
-
-// add adds a uintptr offset to the offAddr.
-func (l offAddr) add(bytes uintptr) offAddr {
-	return offAddr{a: l.a + bytes}
-}
-
-// sub subtracts a uintptr offset from the offAddr.
-func (l offAddr) sub(bytes uintptr) offAddr {
-	return offAddr{a: l.a - bytes}
-}
-
-// diff returns the amount of bytes in between the
-// two offAddrs.
-func (l1 offAddr) diff(l2 offAddr) uintptr {
-	return l1.a - l2.a
-}
-
-// lessThan returns true if l1 is less than l2 in the offset
-// address space.
-func (l1 offAddr) lessThan(l2 offAddr) bool {
-	return (l1.a - arenaBaseOffset) < (l2.a - arenaBaseOffset)
-}
-
-// lessEqual returns true if l1 is less than or equal to l2 in
-// the offset address space.
-func (l1 offAddr) lessEqual(l2 offAddr) bool {
-	return (l1.a - arenaBaseOffset) <= (l2.a - arenaBaseOffset)
-}
-
-// equal returns true if the two offAddr values are equal.
-func (l1 offAddr) equal(l2 offAddr) bool {
-	// No need to compare in the offset space, it
-	// means the same thing.
-	return l1 == l2
-}
-
-// addr returns the virtual address for this offset address.
-func (l offAddr) addr() uintptr {
-	return l.a
-}
-
-// addrRanges is a data structure holding a collection of ranges of
-// address space.
-//
-// The ranges are coalesced eagerly to reduce the
-// number ranges it holds.
-//
-// The slice backing store for this field is persistentalloc'd
-// and thus there is no way to free it.
-//
-// addrRanges is not thread-safe.
-type addrRanges struct {
-	// ranges is a slice of ranges sorted by base.
-	ranges []addrRange
-
-	// totalBytes is the total amount of address space in bytes counted by
-	// this addrRanges.
-	totalBytes uintptr
-
-	// sysStat is the stat to track allocations by this type
-	sysStat *sysMemStat
-}
-
-func (a *addrRanges) init(sysStat *sysMemStat) {
-	ranges := (*notInHeapSlice)(unsafe.Pointer(&a.ranges))
-	ranges.len = 0
-	ranges.cap = 16
-	ranges.array = (*notInHeap)(persistentalloc(unsafe.Sizeof(addrRange{})*uintptr(ranges.cap), goarch.PtrSize, sysStat))
-	a.sysStat = sysStat
-	a.totalBytes = 0
-}
-
-// findSucc returns the first index in a such that addr is
-// less than the base of the addrRange at that index.
-func (a *addrRanges) findSucc(addr uintptr) int {
-	base := offAddr{addr}
-
-	// Narrow down the search space via a binary search
-	// for large addrRanges until we have at most iterMax
-	// candidates left.
-	const iterMax = 8
-	bot, top := 0, len(a.ranges)
-	for top-bot > iterMax {
-		i := ((top - bot) / 2) + bot
-		if a.ranges[i].contains(base.addr()) {
-			// a.ranges[i] contains base, so
-			// its successor is the next index.
-			return i + 1
-		}
-		if base.lessThan(a.ranges[i].base) {
-			// In this case i might actually be
-			// the successor, but we can't be sure
-			// until we check the ones before it.
-			top = i
-		} else {
-			// In this case we know base is
-			// greater than or equal to a.ranges[i].limit-1,
-			// so i is definitely not the successor.
-			// We already checked i, so pick the next
-			// one.
-			bot = i + 1
-		}
-	}
-	// There are top-bot candidates left, so
-	// iterate over them and find the first that
-	// base is strictly less than.
-	for i := bot; i < top; i++ {
-		if base.lessThan(a.ranges[i].base) {
-			return i
-		}
-	}
-	return top
-}
-
-// findAddrGreaterEqual returns the smallest address represented by a
-// that is >= addr. Thus, if the address is represented by a,
-// then it returns addr. The second return value indicates whether
-// such an address exists for addr in a. That is, if addr is larger than
-// any address known to a, the second return value will be false.
-func (a *addrRanges) findAddrGreaterEqual(addr uintptr) (uintptr, bool) {
-	i := a.findSucc(addr)
-	if i == 0 {
-		return a.ranges[0].base.addr(), true
-	}
-	if a.ranges[i-1].contains(addr) {
-		return addr, true
-	}
-	if i < len(a.ranges) {
-		return a.ranges[i].base.addr(), true
-	}
-	return 0, false
-}
-
-// contains returns true if a covers the address addr.
-func (a *addrRanges) contains(addr uintptr) bool {
-	i := a.findSucc(addr)
-	if i == 0 {
-		return false
-	}
-	return a.ranges[i-1].contains(addr)
-}
-
-// add inserts a new address range to a.
-//
-// r must not overlap with any address range in a and r.size() must be > 0.
-func (a *addrRanges) add(r addrRange) {
-	// The copies in this function are potentially expensive, but this data
-	// structure is meant to represent the Go heap. At worst, copying this
-	// would take ~160µs assuming a conservative copying rate of 25 GiB/s (the
-	// copy will almost never trigger a page fault) for a 1 TiB heap with 4 MiB
-	// arenas which is completely discontiguous. ~160µs is still a lot, but in
-	// practice most platforms have 64 MiB arenas (which cuts this by a factor
-	// of 16) and Go heaps are usually mostly contiguous, so the chance that
-	// an addrRanges even grows to that size is extremely low.
-
-	// An empty range has no effect on the set of addresses represented
-	// by a, but passing a zero-sized range is almost always a bug.
-	if r.size() == 0 {
-		print("runtime: range = {", hex(r.base.addr()), ", ", hex(r.limit.addr()), "}\n")
-		throw("attempted to add zero-sized address range")
-	}
-	// Because we assume r is not currently represented in a,
-	// findSucc gives us our insertion index.
-	i := a.findSucc(r.base.addr())
-	coalescesDown := i > 0 && a.ranges[i-1].limit.equal(r.base)
-	coalescesUp := i < len(a.ranges) && r.limit.equal(a.ranges[i].base)
-	if coalescesUp && coalescesDown {
-		// We have neighbors and they both border us.
-		// Merge a.ranges[i-1], r, and a.ranges[i] together into a.ranges[i-1].
-		a.ranges[i-1].limit = a.ranges[i].limit
-
-		// Delete a.ranges[i].
-		copy(a.ranges[i:], a.ranges[i+1:])
-		a.ranges = a.ranges[:len(a.ranges)-1]
-	} else if coalescesDown {
-		// We have a neighbor at a lower address only and it borders us.
-		// Merge the new space into a.ranges[i-1].
-		a.ranges[i-1].limit = r.limit
-	} else if coalescesUp {
-		// We have a neighbor at a higher address only and it borders us.
-		// Merge the new space into a.ranges[i].
-		a.ranges[i].base = r.base
-	} else {
-		// We may or may not have neighbors which don't border us.
-		// Add the new range.
-		if len(a.ranges)+1 > cap(a.ranges) {
-			// Grow the array. Note that this leaks the old array, but since
-			// we're doubling we have at most 2x waste. For a 1 TiB heap and
-			// 4 MiB arenas which are all discontiguous (both very conservative
-			// assumptions), this would waste at most 4 MiB of memory.
-			oldRanges := a.ranges
-			ranges := (*notInHeapSlice)(unsafe.Pointer(&a.ranges))
-			ranges.len = len(oldRanges) + 1
-			ranges.cap = cap(oldRanges) * 2
-			ranges.array = (*notInHeap)(persistentalloc(unsafe.Sizeof(addrRange{})*uintptr(ranges.cap), goarch.PtrSize, a.sysStat))
-
-			// Copy in the old array, but make space for the new range.
-			copy(a.ranges[:i], oldRanges[:i])
-			copy(a.ranges[i+1:], oldRanges[i:])
-		} else {
-			a.ranges = a.ranges[:len(a.ranges)+1]
-			copy(a.ranges[i+1:], a.ranges[i:])
-		}
-		a.ranges[i] = r
-	}
-	a.totalBytes += r.size()
-}
-
-// removeLast removes and returns the highest-addressed contiguous range
-// of a, or the last nBytes of that range, whichever is smaller. If a is
-// empty, it returns an empty range.
-func (a *addrRanges) removeLast(nBytes uintptr) addrRange {
-	if len(a.ranges) == 0 {
-		return addrRange{}
-	}
-	r := a.ranges[len(a.ranges)-1]
-	size := r.size()
-	if size > nBytes {
-		newEnd := r.limit.sub(nBytes)
-		a.ranges[len(a.ranges)-1].limit = newEnd
-		a.totalBytes -= nBytes
-		return addrRange{newEnd, r.limit}
-	}
-	a.ranges = a.ranges[:len(a.ranges)-1]
-	a.totalBytes -= size
-	return r
-}
-
-// removeGreaterEqual removes the ranges of a which are above addr, and additionally
-// splits any range containing addr.
-func (a *addrRanges) removeGreaterEqual(addr uintptr) {
-	pivot := a.findSucc(addr)
-	if pivot == 0 {
-		// addr is before all ranges in a.
-		a.totalBytes = 0
-		a.ranges = a.ranges[:0]
-		return
-	}
-	removed := uintptr(0)
-	for _, r := range a.ranges[pivot:] {
-		removed += r.size()
-	}
-	if r := a.ranges[pivot-1]; r.contains(addr) {
-		removed += r.size()
-		r = r.removeGreaterEqual(addr)
-		if r.size() == 0 {
-			pivot--
-		} else {
-			removed -= r.size()
-			a.ranges[pivot-1] = r
-		}
-	}
-	a.ranges = a.ranges[:pivot]
-	a.totalBytes -= removed
-}
-
-// cloneInto makes a deep clone of a's state into b, re-using
-// b's ranges if able.
-func (a *addrRanges) cloneInto(b *addrRanges) {
-	if len(a.ranges) > cap(b.ranges) {
-		// Grow the array.
-		ranges := (*notInHeapSlice)(unsafe.Pointer(&b.ranges))
-		ranges.len = 0
-		ranges.cap = cap(a.ranges)
-		ranges.array = (*notInHeap)(persistentalloc(unsafe.Sizeof(addrRange{})*uintptr(ranges.cap), goarch.PtrSize, b.sysStat))
-	}
-	b.ranges = b.ranges[:len(a.ranges)]
-	b.totalBytes = a.totalBytes
-	copy(b.ranges, a.ranges)
-}
diff --git a/contrib/go/_std_1.18/src/runtime/mspanset.go b/contrib/go/_std_1.18/src/runtime/mspanset.go
deleted file mode 100644
index 29f14910cc..0000000000
--- a/contrib/go/_std_1.18/src/runtime/mspanset.go
+++ /dev/null
@@ -1,354 +0,0 @@
-// Copyright 2020 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"internal/cpu"
-	"internal/goarch"
-	"runtime/internal/atomic"
-	"unsafe"
-)
-
-// A spanSet is a set of *mspans.
-//
-// spanSet is safe for concurrent push and pop operations.
-type spanSet struct {
-	// A spanSet is a two-level data structure consisting of a
-	// growable spine that points to fixed-sized blocks. The spine
-	// can be accessed without locks, but adding a block or
-	// growing it requires taking the spine lock.
-	//
-	// Because each mspan covers at least 8K of heap and takes at
-	// most 8 bytes in the spanSet, the growth of the spine is
-	// quite limited.
-	//
-	// The spine and all blocks are allocated off-heap, which
-	// allows this to be used in the memory manager and avoids the
-	// need for write barriers on all of these. spanSetBlocks are
-	// managed in a pool, though never freed back to the operating
-	// system. We never release spine memory because there could be
-	// concurrent lock-free access and we're likely to reuse it
-	// anyway. (In principle, we could do this during STW.)
-
-	spineLock mutex
-	spine     unsafe.Pointer // *[N]*spanSetBlock, accessed atomically
-	spineLen  uintptr        // Spine array length, accessed atomically
-	spineCap  uintptr        // Spine array cap, accessed under lock
-
-	// index is the head and tail of the spanSet in a single field.
-	// The head and the tail both represent an index into the logical
-	// concatenation of all blocks, with the head always behind or
-	// equal to the tail (indicating an empty set). This field is
-	// always accessed atomically.
-	//
-	// The head and the tail are only 32 bits wide, which means we
-	// can only support up to 2^32 pushes before a reset. If every
-	// span in the heap were stored in this set, and each span were
-	// the minimum size (1 runtime page, 8 KiB), then roughly the
-	// smallest heap which would be unrepresentable is 32 TiB in size.
-	index headTailIndex
-}
-
-const (
-	spanSetBlockEntries = 512 // 4KB on 64-bit
-	spanSetInitSpineCap = 256 // Enough for 1GB heap on 64-bit
-)
-
-type spanSetBlock struct {
-	// Free spanSetBlocks are managed via a lock-free stack.
-	lfnode
-
-	// popped is the number of pop operations that have occurred on
-	// this block. This number is used to help determine when a block
-	// may be safely recycled.
-	popped uint32
-
-	// spans is the set of spans in this block.
-	spans [spanSetBlockEntries]*mspan
-}
-
-// push adds span s to buffer b. push is safe to call concurrently
-// with other push and pop operations.
-func (b *spanSet) push(s *mspan) {
-	// Obtain our slot.
-	cursor := uintptr(b.index.incTail().tail() - 1)
-	top, bottom := cursor/spanSetBlockEntries, cursor%spanSetBlockEntries
-
-	// Do we need to add a block?
-	spineLen := atomic.Loaduintptr(&b.spineLen)
-	var block *spanSetBlock
-retry:
-	if top < spineLen {
-		spine := atomic.Loadp(unsafe.Pointer(&b.spine))
-		blockp := add(spine, goarch.PtrSize*top)
-		block = (*spanSetBlock)(atomic.Loadp(blockp))
-	} else {
-		// Add a new block to the spine, potentially growing
-		// the spine.
-		lock(&b.spineLock)
-		// spineLen cannot change until we release the lock,
-		// but may have changed while we were waiting.
-		spineLen = atomic.Loaduintptr(&b.spineLen)
-		if top < spineLen {
-			unlock(&b.spineLock)
-			goto retry
-		}
-
-		if spineLen == b.spineCap {
-			// Grow the spine.
-			newCap := b.spineCap * 2
-			if newCap == 0 {
-				newCap = spanSetInitSpineCap
-			}
-			newSpine := persistentalloc(newCap*goarch.PtrSize, cpu.CacheLineSize, &memstats.gcMiscSys)
-			if b.spineCap != 0 {
-				// Blocks are allocated off-heap, so
-				// no write barriers.
-				memmove(newSpine, b.spine, b.spineCap*goarch.PtrSize)
-			}
-			// Spine is allocated off-heap, so no write barrier.
-			atomic.StorepNoWB(unsafe.Pointer(&b.spine), newSpine)
-			b.spineCap = newCap
-			// We can't immediately free the old spine
-			// since a concurrent push with a lower index
-			// could still be reading from it. We let it
-			// leak because even a 1TB heap would waste
-			// less than 2MB of memory on old spines. If
-			// this is a problem, we could free old spines
-			// during STW.
-		}
-
-		// Allocate a new block from the pool.
-		block = spanSetBlockPool.alloc()
-
-		// Add it to the spine.
-		blockp := add(b.spine, goarch.PtrSize*top)
-		// Blocks are allocated off-heap, so no write barrier.
-		atomic.StorepNoWB(blockp, unsafe.Pointer(block))
-		atomic.Storeuintptr(&b.spineLen, spineLen+1)
-		unlock(&b.spineLock)
-	}
-
-	// We have a block. Insert the span atomically, since there may be
-	// concurrent readers via the block API.
-	atomic.StorepNoWB(unsafe.Pointer(&block.spans[bottom]), unsafe.Pointer(s))
-}
-
-// pop removes and returns a span from buffer b, or nil if b is empty.
-// pop is safe to call concurrently with other pop and push operations.
-func (b *spanSet) pop() *mspan {
-	var head, tail uint32
-claimLoop:
-	for {
-		headtail := b.index.load()
-		head, tail = headtail.split()
-		if head >= tail {
-			// The buf is empty, as far as we can tell.
-			return nil
-		}
-		// Check if the head position we want to claim is actually
-		// backed by a block.
-		spineLen := atomic.Loaduintptr(&b.spineLen)
-		if spineLen <= uintptr(head)/spanSetBlockEntries {
-			// We're racing with a spine growth and the allocation of
-			// a new block (and maybe a new spine!), and trying to grab
-			// the span at the index which is currently being pushed.
-			// Instead of spinning, let's just notify the caller that
-			// there's nothing currently here. Spinning on this is
-			// almost definitely not worth it.
-			return nil
-		}
-		// Try to claim the current head by CASing in an updated head.
-		// This may fail transiently due to a push which modifies the
-		// tail, so keep trying while the head isn't changing.
-		want := head
-		for want == head {
-			if b.index.cas(headtail, makeHeadTailIndex(want+1, tail)) {
-				break claimLoop
-			}
-			headtail = b.index.load()
-			head, tail = headtail.split()
-		}
-		// We failed to claim the spot we were after and the head changed,
-		// meaning a popper got ahead of us. Try again from the top because
-		// the buf may not be empty.
-	}
-	top, bottom := head/spanSetBlockEntries, head%spanSetBlockEntries
-
-	// We may be reading a stale spine pointer, but because the length
-	// grows monotonically and we've already verified it, we'll definitely
-	// be reading from a valid block.
-	spine := atomic.Loadp(unsafe.Pointer(&b.spine))
-	blockp := add(spine, goarch.PtrSize*uintptr(top))
-
-	// Given that the spine length is correct, we know we will never
-	// see a nil block here, since the length is always updated after
-	// the block is set.
-	block := (*spanSetBlock)(atomic.Loadp(blockp))
-	s := (*mspan)(atomic.Loadp(unsafe.Pointer(&block.spans[bottom])))
-	for s == nil {
-		// We raced with the span actually being set, but given that we
-		// know a block for this span exists, the race window here is
-		// extremely small. Try again.
-		s = (*mspan)(atomic.Loadp(unsafe.Pointer(&block.spans[bottom])))
-	}
-	// Clear the pointer. This isn't strictly necessary, but defensively
-	// avoids accidentally re-using blocks which could lead to memory
-	// corruption. This way, we'll get a nil pointer access instead.
-	atomic.StorepNoWB(unsafe.Pointer(&block.spans[bottom]), nil)
-
-	// Increase the popped count. If we are the last possible popper
-	// in the block (note that bottom need not equal spanSetBlockEntries-1
-	// due to races) then it's our resposibility to free the block.
-	//
-	// If we increment popped to spanSetBlockEntries, we can be sure that
-	// we're the last popper for this block, and it's thus safe to free it.
-	// Every other popper must have crossed this barrier (and thus finished
-	// popping its corresponding mspan) by the time we get here. Because
-	// we're the last popper, we also don't have to worry about concurrent
-	// pushers (there can't be any). Note that we may not be the popper
-	// which claimed the last slot in the block, we're just the last one
-	// to finish popping.
-	if atomic.Xadd(&block.popped, 1) == spanSetBlockEntries {
-		// Clear the block's pointer.
-		atomic.StorepNoWB(blockp, nil)
-
-		// Return the block to the block pool.
-		spanSetBlockPool.free(block)
-	}
-	return s
-}
-
-// reset resets a spanSet which is empty. It will also clean up
-// any left over blocks.
-//
-// Throws if the buf is not empty.
-//
-// reset may not be called concurrently with any other operations
-// on the span set.
-func (b *spanSet) reset() {
-	head, tail := b.index.load().split()
-	if head < tail {
-		print("head = ", head, ", tail = ", tail, "\n")
-		throw("attempt to clear non-empty span set")
-	}
-	top := head / spanSetBlockEntries
-	if uintptr(top) < b.spineLen {
-		// If the head catches up to the tail and the set is empty,
-		// we may not clean up the block containing the head and tail
-		// since it may be pushed into again. In order to avoid leaking
-		// memory since we're going to reset the head and tail, clean
-		// up such a block now, if it exists.
-		blockp := (**spanSetBlock)(add(b.spine, goarch.PtrSize*uintptr(top)))
-		block := *blockp
-		if block != nil {
-			// Sanity check the popped value.
-			if block.popped == 0 {
-				// popped should never be zero because that means we have
-				// pushed at least one value but not yet popped if this
-				// block pointer is not nil.
-				throw("span set block with unpopped elements found in reset")
-			}
-			if block.popped == spanSetBlockEntries {
-				// popped should also never be equal to spanSetBlockEntries
-				// because the last popper should have made the block pointer
-				// in this slot nil.
-				throw("fully empty unfreed span set block found in reset")
-			}
-
-			// Clear the pointer to the block.
-			atomic.StorepNoWB(unsafe.Pointer(blockp), nil)
-
-			// Return the block to the block pool.
-			spanSetBlockPool.free(block)
-		}
-	}
-	b.index.reset()
-	atomic.Storeuintptr(&b.spineLen, 0)
-}
-
-// spanSetBlockPool is a global pool of spanSetBlocks.
-var spanSetBlockPool spanSetBlockAlloc
-
-// spanSetBlockAlloc represents a concurrent pool of spanSetBlocks.
-type spanSetBlockAlloc struct {
-	stack lfstack
-}
-
-// alloc tries to grab a spanSetBlock out of the pool, and if it fails
-// persistentallocs a new one and returns it.
-func (p *spanSetBlockAlloc) alloc() *spanSetBlock {
-	if s := (*spanSetBlock)(p.stack.pop()); s != nil {
-		return s
-	}
-	return (*spanSetBlock)(persistentalloc(unsafe.Sizeof(spanSetBlock{}), cpu.CacheLineSize, &memstats.gcMiscSys))
-}
-
-// free returns a spanSetBlock back to the pool.
-func (p *spanSetBlockAlloc) free(block *spanSetBlock) {
-	atomic.Store(&block.popped, 0)
-	p.stack.push(&block.lfnode)
-}
-
-// haidTailIndex represents a combined 32-bit head and 32-bit tail
-// of a queue into a single 64-bit value.
-type headTailIndex uint64
-
-// makeHeadTailIndex creates a headTailIndex value from a separate
-// head and tail.
-func makeHeadTailIndex(head, tail uint32) headTailIndex {
-	return headTailIndex(uint64(head)<<32 | uint64(tail))
-}
-
-// head returns the head of a headTailIndex value.
-func (h headTailIndex) head() uint32 {
-	return uint32(h >> 32)
-}
-
-// tail returns the tail of a headTailIndex value.
-func (h headTailIndex) tail() uint32 {
-	return uint32(h)
-}
-
-// split splits the headTailIndex value into its parts.
-func (h headTailIndex) split() (head uint32, tail uint32) {
-	return h.head(), h.tail()
-}
-
-// load atomically reads a headTailIndex value.
-func (h *headTailIndex) load() headTailIndex {
-	return headTailIndex(atomic.Load64((*uint64)(h)))
-}
-
-// cas atomically compares-and-swaps a headTailIndex value.
-func (h *headTailIndex) cas(old, new headTailIndex) bool {
-	return atomic.Cas64((*uint64)(h), uint64(old), uint64(new))
-}
-
-// incHead atomically increments the head of a headTailIndex.
-func (h *headTailIndex) incHead() headTailIndex {
-	return headTailIndex(atomic.Xadd64((*uint64)(h), (1 << 32)))
-}
-
-// decHead atomically decrements the head of a headTailIndex.
-func (h *headTailIndex) decHead() headTailIndex {
-	return headTailIndex(atomic.Xadd64((*uint64)(h), -(1 << 32)))
-}
-
-// incTail atomically increments the tail of a headTailIndex.
-func (h *headTailIndex) incTail() headTailIndex {
-	ht := headTailIndex(atomic.Xadd64((*uint64)(h), +1))
-	// Check for overflow.
-	if ht.tail() == 0 {
-		print("runtime: head = ", ht.head(), ", tail = ", ht.tail(), "\n")
-		throw("headTailIndex overflow")
-	}
-	return ht
-}
-
-// reset clears the headTailIndex to (0, 0).
-func (h *headTailIndex) reset() {
-	atomic.Store64((*uint64)(h), 0)
-}
diff --git a/contrib/go/_std_1.18/src/runtime/mstats.go b/contrib/go/_std_1.18/src/runtime/mstats.go
deleted file mode 100644
index 2c1ec79bf8..0000000000
--- a/contrib/go/_std_1.18/src/runtime/mstats.go
+++ /dev/null
@@ -1,928 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Memory statistics
-
-package runtime
-
-import (
-	"runtime/internal/atomic"
-	"unsafe"
-)
-
-// Statistics.
-//
-// For detailed descriptions see the documentation for MemStats.
-// Fields that differ from MemStats are further documented here.
-//
-// Many of these fields are updated on the fly, while others are only
-// updated when updatememstats is called.
-type mstats struct {
-	// General statistics.
-	alloc       uint64 // bytes allocated and not yet freed
-	total_alloc uint64 // bytes allocated (even if freed)
-	sys         uint64 // bytes obtained from system (should be sum of xxx_sys below, no locking, approximate)
-	nlookup     uint64 // number of pointer lookups (unused)
-	nmalloc     uint64 // number of mallocs
-	nfree       uint64 // number of frees
-
-	// Statistics about malloc heap.
-	// Updated atomically, or with the world stopped.
-	//
-	// Like MemStats, heap_sys and heap_inuse do not count memory
-	// in manually-managed spans.
-	heap_sys      sysMemStat // virtual address space obtained from system for GC'd heap
-	heap_inuse    uint64     // bytes in mSpanInUse spans
-	heap_released uint64     // bytes released to the os
-
-	// heap_objects is not used by the runtime directly and instead
-	// computed on the fly by updatememstats.
-	heap_objects uint64 // total number of allocated objects
-
-	// Statistics about stacks.
-	stacks_inuse uint64     // bytes in manually-managed stack spans; computed by updatememstats
-	stacks_sys   sysMemStat // only counts newosproc0 stack in mstats; differs from MemStats.StackSys
-
-	// Statistics about allocation of low-level fixed-size structures.
-	// Protected by FixAlloc locks.
-	mspan_inuse  uint64 // mspan structures
-	mspan_sys    sysMemStat
-	mcache_inuse uint64 // mcache structures
-	mcache_sys   sysMemStat
-	buckhash_sys sysMemStat // profiling bucket hash table
-
-	// Statistics about GC overhead.
-	gcWorkBufInUse           uint64     // computed by updatememstats
-	gcProgPtrScalarBitsInUse uint64     // computed by updatememstats
-	gcMiscSys                sysMemStat // updated atomically or during STW
-
-	// Miscellaneous statistics.
-	other_sys sysMemStat // updated atomically or during STW
-
-	// Statistics about the garbage collector.
-
-	// Protected by mheap or stopping the world during GC.
-	last_gc_unix    uint64 // last gc (in unix time)
-	pause_total_ns  uint64
-	pause_ns        [256]uint64 // circular buffer of recent gc pause lengths
-	pause_end       [256]uint64 // circular buffer of recent gc end times (nanoseconds since 1970)
-	numgc           uint32
-	numforcedgc     uint32  // number of user-forced GCs
-	gc_cpu_fraction float64 // fraction of CPU time used by GC
-	enablegc        bool
-	debuggc         bool
-
-	// Statistics about allocation size classes.
-
-	by_size [_NumSizeClasses]struct {
-		size    uint32
-		nmalloc uint64
-		nfree   uint64
-	}
-
-	// Add an uint32 for even number of size classes to align below fields
-	// to 64 bits for atomic operations on 32 bit platforms.
-	_ [1 - _NumSizeClasses%2]uint32
-
-	last_gc_nanotime uint64 // last gc (monotonic time)
-	last_heap_inuse  uint64 // heap_inuse at mark termination of the previous GC
-
-	// heapStats is a set of statistics
-	heapStats consistentHeapStats
-
-	// _ uint32 // ensure gcPauseDist is aligned
-
-	// gcPauseDist represents the distribution of all GC-related
-	// application pauses in the runtime.
-	//
-	// Each individual pause is counted separately, unlike pause_ns.
-	gcPauseDist timeHistogram
-}
-
-var memstats mstats
-
-// A MemStats records statistics about the memory allocator.
-type MemStats struct {
-	// General statistics.
-
-	// Alloc is bytes of allocated heap objects.
-	//
-	// This is the same as HeapAlloc (see below).
-	Alloc uint64
-
-	// TotalAlloc is cumulative bytes allocated for heap objects.
-	//
-	// TotalAlloc increases as heap objects are allocated, but
-	// unlike Alloc and HeapAlloc, it does not decrease when
-	// objects are freed.
-	TotalAlloc uint64
-
-	// Sys is the total bytes of memory obtained from the OS.
-	//
-	// Sys is the sum of the XSys fields below. Sys measures the
-	// virtual address space reserved by the Go runtime for the
-	// heap, stacks, and other internal data structures. It's
-	// likely that not all of the virtual address space is backed
-	// by physical memory at any given moment, though in general
-	// it all was at some point.
-	Sys uint64
-
-	// Lookups is the number of pointer lookups performed by the
-	// runtime.
-	//
-	// This is primarily useful for debugging runtime internals.
-	Lookups uint64
-
-	// Mallocs is the cumulative count of heap objects allocated.
-	// The number of live objects is Mallocs - Frees.
-	Mallocs uint64
-
-	// Frees is the cumulative count of heap objects freed.
-	Frees uint64
-
-	// Heap memory statistics.
-	//
-	// Interpreting the heap statistics requires some knowledge of
-	// how Go organizes memory. Go divides the virtual address
-	// space of the heap into "spans", which are contiguous
-	// regions of memory 8K or larger. A span may be in one of
-	// three states:
-	//
-	// An "idle" span contains no objects or other data. The
-	// physical memory backing an idle span can be released back
-	// to the OS (but the virtual address space never is), or it
-	// can be converted into an "in use" or "stack" span.
-	//
-	// An "in use" span contains at least one heap object and may
-	// have free space available to allocate more heap objects.
-	//
-	// A "stack" span is used for goroutine stacks. Stack spans
-	// are not considered part of the heap. A span can change
-	// between heap and stack memory; it is never used for both
-	// simultaneously.
-
-	// HeapAlloc is bytes of allocated heap objects.
-	//
-	// "Allocated" heap objects include all reachable objects, as
-	// well as unreachable objects that the garbage collector has
-	// not yet freed. Specifically, HeapAlloc increases as heap
-	// objects are allocated and decreases as the heap is swept
-	// and unreachable objects are freed. Sweeping occurs
-	// incrementally between GC cycles, so these two processes
-	// occur simultaneously, and as a result HeapAlloc tends to
-	// change smoothly (in contrast with the sawtooth that is
-	// typical of stop-the-world garbage collectors).
-	HeapAlloc uint64
-
-	// HeapSys is bytes of heap memory obtained from the OS.
-	//
-	// HeapSys measures the amount of virtual address space
-	// reserved for the heap. This includes virtual address space
-	// that has been reserved but not yet used, which consumes no
-	// physical memory, but tends to be small, as well as virtual
-	// address space for which the physical memory has been
-	// returned to the OS after it became unused (see HeapReleased
-	// for a measure of the latter).
-	//
-	// HeapSys estimates the largest size the heap has had.
-	HeapSys uint64
-
-	// HeapIdle is bytes in idle (unused) spans.
-	//
-	// Idle spans have no objects in them. These spans could be
-	// (and may already have been) returned to the OS, or they can
-	// be reused for heap allocations, or they can be reused as
-	// stack memory.
-	//
-	// HeapIdle minus HeapReleased estimates the amount of memory
-	// that could be returned to the OS, but is being retained by
-	// the runtime so it can grow the heap without requesting more
-	// memory from the OS. If this difference is significantly
-	// larger than the heap size, it indicates there was a recent
-	// transient spike in live heap size.
-	HeapIdle uint64
-
-	// HeapInuse is bytes in in-use spans.
-	//
-	// In-use spans have at least one object in them. These spans
-	// can only be used for other objects of roughly the same
-	// size.
-	//
-	// HeapInuse minus HeapAlloc estimates the amount of memory
-	// that has been dedicated to particular size classes, but is
-	// not currently being used. This is an upper bound on
-	// fragmentation, but in general this memory can be reused
-	// efficiently.
-	HeapInuse uint64
-
-	// HeapReleased is bytes of physical memory returned to the OS.
-	//
-	// This counts heap memory from idle spans that was returned
-	// to the OS and has not yet been reacquired for the heap.
-	HeapReleased uint64
-
-	// HeapObjects is the number of allocated heap objects.
-	//
-	// Like HeapAlloc, this increases as objects are allocated and
-	// decreases as the heap is swept and unreachable objects are
-	// freed.
-	HeapObjects uint64
-
-	// Stack memory statistics.
-	//
-	// Stacks are not considered part of the heap, but the runtime
-	// can reuse a span of heap memory for stack memory, and
-	// vice-versa.
-
-	// StackInuse is bytes in stack spans.
-	//
-	// In-use stack spans have at least one stack in them. These
-	// spans can only be used for other stacks of the same size.
-	//
-	// There is no StackIdle because unused stack spans are
-	// returned to the heap (and hence counted toward HeapIdle).
-	StackInuse uint64
-
-	// StackSys is bytes of stack memory obtained from the OS.
-	//
-	// StackSys is StackInuse, plus any memory obtained directly
-	// from the OS for OS thread stacks (which should be minimal).
-	StackSys uint64
-
-	// Off-heap memory statistics.
-	//
-	// The following statistics measure runtime-internal
-	// structures that are not allocated from heap memory (usually
-	// because they are part of implementing the heap). Unlike
-	// heap or stack memory, any memory allocated to these
-	// structures is dedicated to these structures.
-	//
-	// These are primarily useful for debugging runtime memory
-	// overheads.
-
-	// MSpanInuse is bytes of allocated mspan structures.
-	MSpanInuse uint64
-
-	// MSpanSys is bytes of memory obtained from the OS for mspan
-	// structures.
-	MSpanSys uint64
-
-	// MCacheInuse is bytes of allocated mcache structures.
-	MCacheInuse uint64
-
-	// MCacheSys is bytes of memory obtained from the OS for
-	// mcache structures.
-	MCacheSys uint64
-
-	// BuckHashSys is bytes of memory in profiling bucket hash tables.
-	BuckHashSys uint64
-
-	// GCSys is bytes of memory in garbage collection metadata.
-	GCSys uint64
-
-	// OtherSys is bytes of memory in miscellaneous off-heap
-	// runtime allocations.
-	OtherSys uint64
-
-	// Garbage collector statistics.
-
-	// NextGC is the target heap size of the next GC cycle.
-	//
-	// The garbage collector's goal is to keep HeapAlloc ≤ NextGC.
-	// At the end of each GC cycle, the target for the next cycle
-	// is computed based on the amount of reachable data and the
-	// value of GOGC.
-	NextGC uint64
-
-	// LastGC is the time the last garbage collection finished, as
-	// nanoseconds since 1970 (the UNIX epoch).
-	LastGC uint64
-
-	// PauseTotalNs is the cumulative nanoseconds in GC
-	// stop-the-world pauses since the program started.
-	//
-	// During a stop-the-world pause, all goroutines are paused
-	// and only the garbage collector can run.
-	PauseTotalNs uint64
-
-	// PauseNs is a circular buffer of recent GC stop-the-world
-	// pause times in nanoseconds.
-	//
-	// The most recent pause is at PauseNs[(NumGC+255)%256]. In
-	// general, PauseNs[N%256] records the time paused in the most
-	// recent N%256th GC cycle. There may be multiple pauses per
-	// GC cycle; this is the sum of all pauses during a cycle.
-	PauseNs [256]uint64
-
-	// PauseEnd is a circular buffer of recent GC pause end times,
-	// as nanoseconds since 1970 (the UNIX epoch).
-	//
-	// This buffer is filled the same way as PauseNs. There may be
-	// multiple pauses per GC cycle; this records the end of the
-	// last pause in a cycle.
-	PauseEnd [256]uint64
-
-	// NumGC is the number of completed GC cycles.
-	NumGC uint32
-
-	// NumForcedGC is the number of GC cycles that were forced by
-	// the application calling the GC function.
-	NumForcedGC uint32
-
-	// GCCPUFraction is the fraction of this program's available
-	// CPU time used by the GC since the program started.
-	//
-	// GCCPUFraction is expressed as a number between 0 and 1,
-	// where 0 means GC has consumed none of this program's CPU. A
-	// program's available CPU time is defined as the integral of
-	// GOMAXPROCS since the program started. That is, if
-	// GOMAXPROCS is 2 and a program has been running for 10
-	// seconds, its "available CPU" is 20 seconds. GCCPUFraction
-	// does not include CPU time used for write barrier activity.
-	//
-	// This is the same as the fraction of CPU reported by
-	// GODEBUG=gctrace=1.
-	GCCPUFraction float64
-
-	// EnableGC indicates that GC is enabled. It is always true,
-	// even if GOGC=off.
-	EnableGC bool
-
-	// DebugGC is currently unused.
-	DebugGC bool
-
-	// BySize reports per-size class allocation statistics.
-	//
-	// BySize[N] gives statistics for allocations of size S where
-	// BySize[N-1].Size < S ≤ BySize[N].Size.
-	//
-	// This does not report allocations larger than BySize[60].Size.
-	BySize [61]struct {
-		// Size is the maximum byte size of an object in this
-		// size class.
-		Size uint32
-
-		// Mallocs is the cumulative count of heap objects
-		// allocated in this size class. The cumulative bytes
-		// of allocation is Size*Mallocs. The number of live
-		// objects in this size class is Mallocs - Frees.
-		Mallocs uint64
-
-		// Frees is the cumulative count of heap objects freed
-		// in this size class.
-		Frees uint64
-	}
-}
-
-func init() {
-	if offset := unsafe.Offsetof(memstats.heapStats); offset%8 != 0 {
-		println(offset)
-		throw("memstats.heapStats not aligned to 8 bytes")
-	}
-	if offset := unsafe.Offsetof(memstats.gcPauseDist); offset%8 != 0 {
-		println(offset)
-		throw("memstats.gcPauseDist not aligned to 8 bytes")
-	}
-	// Ensure the size of heapStatsDelta causes adjacent fields/slots (e.g.
-	// [3]heapStatsDelta) to be 8-byte aligned.
-	if size := unsafe.Sizeof(heapStatsDelta{}); size%8 != 0 {
-		println(size)
-		throw("heapStatsDelta not a multiple of 8 bytes in size")
-	}
-}
-
-// ReadMemStats populates m with memory allocator statistics.
-//
-// The returned memory allocator statistics are up to date as of the
-// call to ReadMemStats. This is in contrast with a heap profile,
-// which is a snapshot as of the most recently completed garbage
-// collection cycle.
-func ReadMemStats(m *MemStats) {
-	stopTheWorld("read mem stats")
-
-	systemstack(func() {
-		readmemstats_m(m)
-	})
-
-	startTheWorld()
-}
-
-func readmemstats_m(stats *MemStats) {
-	updatememstats()
-
-	stats.Alloc = memstats.alloc
-	stats.TotalAlloc = memstats.total_alloc
-	stats.Sys = memstats.sys
-	stats.Mallocs = memstats.nmalloc
-	stats.Frees = memstats.nfree
-	stats.HeapAlloc = memstats.alloc
-	stats.HeapSys = memstats.heap_sys.load()
-	// By definition, HeapIdle is memory that was mapped
-	// for the heap but is not currently used to hold heap
-	// objects. It also specifically is memory that can be
-	// used for other purposes, like stacks, but this memory
-	// is subtracted out of HeapSys before it makes that
-	// transition. Put another way:
-	//
-	// heap_sys = bytes allocated from the OS for the heap - bytes ultimately used for non-heap purposes
-	// heap_idle = bytes allocated from the OS for the heap - bytes ultimately used for any purpose
-	//
-	// or
-	//
-	// heap_sys = sys - stacks_inuse - gcWorkBufInUse - gcProgPtrScalarBitsInUse
-	// heap_idle = sys - stacks_inuse - gcWorkBufInUse - gcProgPtrScalarBitsInUse - heap_inuse
-	//
-	// => heap_idle = heap_sys - heap_inuse
-	stats.HeapIdle = memstats.heap_sys.load() - memstats.heap_inuse
-	stats.HeapInuse = memstats.heap_inuse
-	stats.HeapReleased = memstats.heap_released
-	stats.HeapObjects = memstats.heap_objects
-	stats.StackInuse = memstats.stacks_inuse
-	// memstats.stacks_sys is only memory mapped directly for OS stacks.
-	// Add in heap-allocated stack memory for user consumption.
-	stats.StackSys = memstats.stacks_inuse + memstats.stacks_sys.load()
-	stats.MSpanInuse = memstats.mspan_inuse
-	stats.MSpanSys = memstats.mspan_sys.load()
-	stats.MCacheInuse = memstats.mcache_inuse
-	stats.MCacheSys = memstats.mcache_sys.load()
-	stats.BuckHashSys = memstats.buckhash_sys.load()
-	// MemStats defines GCSys as an aggregate of all memory related
-	// to the memory management system, but we track this memory
-	// at a more granular level in the runtime.
-	stats.GCSys = memstats.gcMiscSys.load() + memstats.gcWorkBufInUse + memstats.gcProgPtrScalarBitsInUse
-	stats.OtherSys = memstats.other_sys.load()
-	stats.NextGC = gcController.heapGoal
-	stats.LastGC = memstats.last_gc_unix
-	stats.PauseTotalNs = memstats.pause_total_ns
-	stats.PauseNs = memstats.pause_ns
-	stats.PauseEnd = memstats.pause_end
-	stats.NumGC = memstats.numgc
-	stats.NumForcedGC = memstats.numforcedgc
-	stats.GCCPUFraction = memstats.gc_cpu_fraction
-	stats.EnableGC = true
-
-	// Handle BySize. Copy N values, where N is
-	// the minimum of the lengths of the two arrays.
-	// Unfortunately copy() won't work here because
-	// the arrays have different structs.
-	//
-	// TODO(mknyszek): Consider renaming the fields
-	// of by_size's elements to align so we can use
-	// the copy built-in.
-	bySizeLen := len(stats.BySize)
-	if l := len(memstats.by_size); l < bySizeLen {
-		bySizeLen = l
-	}
-	for i := 0; i < bySizeLen; i++ {
-		stats.BySize[i].Size = memstats.by_size[i].size
-		stats.BySize[i].Mallocs = memstats.by_size[i].nmalloc
-		stats.BySize[i].Frees = memstats.by_size[i].nfree
-	}
-}
-
-//go:linkname readGCStats runtime/debug.readGCStats
-func readGCStats(pauses *[]uint64) {
-	systemstack(func() {
-		readGCStats_m(pauses)
-	})
-}
-
-// readGCStats_m must be called on the system stack because it acquires the heap
-// lock. See mheap for details.
-//go:systemstack
-func readGCStats_m(pauses *[]uint64) {
-	p := *pauses
-	// Calling code in runtime/debug should make the slice large enough.
-	if cap(p) < len(memstats.pause_ns)+3 {
-		throw("short slice passed to readGCStats")
-	}
-
-	// Pass back: pauses, pause ends, last gc (absolute time), number of gc, total pause ns.
-	lock(&mheap_.lock)
-
-	n := memstats.numgc
-	if n > uint32(len(memstats.pause_ns)) {
-		n = uint32(len(memstats.pause_ns))
-	}
-
-	// The pause buffer is circular. The most recent pause is at
-	// pause_ns[(numgc-1)%len(pause_ns)], and then backward
-	// from there to go back farther in time. We deliver the times
-	// most recent first (in p[0]).
-	p = p[:cap(p)]
-	for i := uint32(0); i < n; i++ {
-		j := (memstats.numgc - 1 - i) % uint32(len(memstats.pause_ns))
-		p[i] = memstats.pause_ns[j]
-		p[n+i] = memstats.pause_end[j]
-	}
-
-	p[n+n] = memstats.last_gc_unix
-	p[n+n+1] = uint64(memstats.numgc)
-	p[n+n+2] = memstats.pause_total_ns
-	unlock(&mheap_.lock)
-	*pauses = p[:n+n+3]
-}
-
-// Updates the memstats structure.
-//
-// The world must be stopped.
-//
-//go:nowritebarrier
-func updatememstats() {
-	assertWorldStopped()
-
-	// Flush mcaches to mcentral before doing anything else.
-	//
-	// Flushing to the mcentral may in general cause stats to
-	// change as mcentral data structures are manipulated.
-	systemstack(flushallmcaches)
-
-	memstats.mcache_inuse = uint64(mheap_.cachealloc.inuse)
-	memstats.mspan_inuse = uint64(mheap_.spanalloc.inuse)
-	memstats.sys = memstats.heap_sys.load() + memstats.stacks_sys.load() + memstats.mspan_sys.load() +
-		memstats.mcache_sys.load() + memstats.buckhash_sys.load() + memstats.gcMiscSys.load() +
-		memstats.other_sys.load()
-
-	// Calculate memory allocator stats.
-	// During program execution we only count number of frees and amount of freed memory.
-	// Current number of alive objects in the heap and amount of alive heap memory
-	// are calculated by scanning all spans.
-	// Total number of mallocs is calculated as number of frees plus number of alive objects.
-	// Similarly, total amount of allocated memory is calculated as amount of freed memory
-	// plus amount of alive heap memory.
-	memstats.alloc = 0
-	memstats.total_alloc = 0
-	memstats.nmalloc = 0
-	memstats.nfree = 0
-	for i := 0; i < len(memstats.by_size); i++ {
-		memstats.by_size[i].nmalloc = 0
-		memstats.by_size[i].nfree = 0
-	}
-	// Collect consistent stats, which are the source-of-truth in the some cases.
-	var consStats heapStatsDelta
-	memstats.heapStats.unsafeRead(&consStats)
-
-	// Collect large allocation stats.
-	totalAlloc := consStats.largeAlloc
-	memstats.nmalloc += consStats.largeAllocCount
-	totalFree := consStats.largeFree
-	memstats.nfree += consStats.largeFreeCount
-
-	// Collect per-sizeclass stats.
-	for i := 0; i < _NumSizeClasses; i++ {
-		// Malloc stats.
-		a := consStats.smallAllocCount[i]
-		totalAlloc += a * uint64(class_to_size[i])
-		memstats.nmalloc += a
-		memstats.by_size[i].nmalloc = a
-
-		// Free stats.
-		f := consStats.smallFreeCount[i]
-		totalFree += f * uint64(class_to_size[i])
-		memstats.nfree += f
-		memstats.by_size[i].nfree = f
-	}
-
-	// Account for tiny allocations.
-	memstats.nfree += consStats.tinyAllocCount
-	memstats.nmalloc += consStats.tinyAllocCount
-
-	// Calculate derived stats.
-	memstats.total_alloc = totalAlloc
-	memstats.alloc = totalAlloc - totalFree
-	memstats.heap_objects = memstats.nmalloc - memstats.nfree
-
-	memstats.stacks_inuse = uint64(consStats.inStacks)
-	memstats.gcWorkBufInUse = uint64(consStats.inWorkBufs)
-	memstats.gcProgPtrScalarBitsInUse = uint64(consStats.inPtrScalarBits)
-
-	// We also count stacks_inuse, gcWorkBufInUse, and gcProgPtrScalarBitsInUse as sys memory.
-	memstats.sys += memstats.stacks_inuse + memstats.gcWorkBufInUse + memstats.gcProgPtrScalarBitsInUse
-
-	// The world is stopped, so the consistent stats (after aggregation)
-	// should be identical to some combination of memstats. In particular:
-	//
-	// * heap_inuse == inHeap
-	// * heap_released == released
-	// * heap_sys - heap_released == committed - inStacks - inWorkBufs - inPtrScalarBits
-	//
-	// Check if that's actually true.
-	//
-	// TODO(mknyszek): Maybe don't throw here. It would be bad if a
-	// bug in otherwise benign accounting caused the whole application
-	// to crash.
-	if memstats.heap_inuse != uint64(consStats.inHeap) {
-		print("runtime: heap_inuse=", memstats.heap_inuse, "\n")
-		print("runtime: consistent value=", consStats.inHeap, "\n")
-		throw("heap_inuse and consistent stats are not equal")
-	}
-	if memstats.heap_released != uint64(consStats.released) {
-		print("runtime: heap_released=", memstats.heap_released, "\n")
-		print("runtime: consistent value=", consStats.released, "\n")
-		throw("heap_released and consistent stats are not equal")
-	}
-	globalRetained := memstats.heap_sys.load() - memstats.heap_released
-	consRetained := uint64(consStats.committed - consStats.inStacks - consStats.inWorkBufs - consStats.inPtrScalarBits)
-	if globalRetained != consRetained {
-		print("runtime: global value=", globalRetained, "\n")
-		print("runtime: consistent value=", consRetained, "\n")
-		throw("measures of the retained heap are not equal")
-	}
-}
-
-// flushmcache flushes the mcache of allp[i].
-//
-// The world must be stopped.
-//
-//go:nowritebarrier
-func flushmcache(i int) {
-	assertWorldStopped()
-
-	p := allp[i]
-	c := p.mcache
-	if c == nil {
-		return
-	}
-	c.releaseAll()
-	stackcache_clear(c)
-}
-
-// flushallmcaches flushes the mcaches of all Ps.
-//
-// The world must be stopped.
-//
-//go:nowritebarrier
-func flushallmcaches() {
-	assertWorldStopped()
-
-	for i := 0; i < int(gomaxprocs); i++ {
-		flushmcache(i)
-	}
-}
-
-// sysMemStat represents a global system statistic that is managed atomically.
-//
-// This type must structurally be a uint64 so that mstats aligns with MemStats.
-type sysMemStat uint64
-
-// load atomically reads the value of the stat.
-//
-// Must be nosplit as it is called in runtime initialization, e.g. newosproc0.
-//go:nosplit
-func (s *sysMemStat) load() uint64 {
-	return atomic.Load64((*uint64)(s))
-}
-
-// add atomically adds the sysMemStat by n.
-//
-// Must be nosplit as it is called in runtime initialization, e.g. newosproc0.
-//go:nosplit
-func (s *sysMemStat) add(n int64) {
-	if s == nil {
-		return
-	}
-	val := atomic.Xadd64((*uint64)(s), n)
-	if (n > 0 && int64(val) < n) || (n < 0 && int64(val)+n < n) {
-		print("runtime: val=", val, " n=", n, "\n")
-		throw("sysMemStat overflow")
-	}
-}
-
-// heapStatsDelta contains deltas of various runtime memory statistics
-// that need to be updated together in order for them to be kept
-// consistent with one another.
-type heapStatsDelta struct {
-	// Memory stats.
-	committed       int64 // byte delta of memory committed
-	released        int64 // byte delta of released memory generated
-	inHeap          int64 // byte delta of memory placed in the heap
-	inStacks        int64 // byte delta of memory reserved for stacks
-	inWorkBufs      int64 // byte delta of memory reserved for work bufs
-	inPtrScalarBits int64 // byte delta of memory reserved for unrolled GC prog bits
-
-	// Allocator stats.
-	//
-	// These are all uint64 because they're cumulative, and could quickly wrap
-	// around otherwise.
-	tinyAllocCount  uint64                  // number of tiny allocations
-	largeAlloc      uint64                  // bytes allocated for large objects
-	largeAllocCount uint64                  // number of large object allocations
-	smallAllocCount [_NumSizeClasses]uint64 // number of allocs for small objects
-	largeFree       uint64                  // bytes freed for large objects (>maxSmallSize)
-	largeFreeCount  uint64                  // number of frees for large objects (>maxSmallSize)
-	smallFreeCount  [_NumSizeClasses]uint64 // number of frees for small objects (<=maxSmallSize)
-
-	// NOTE: This struct must be a multiple of 8 bytes in size because it
-	// is stored in an array. If it's not, atomic accesses to the above
-	// fields may be unaligned and fail on 32-bit platforms.
-}
-
-// merge adds in the deltas from b into a.
-func (a *heapStatsDelta) merge(b *heapStatsDelta) {
-	a.committed += b.committed
-	a.released += b.released
-	a.inHeap += b.inHeap
-	a.inStacks += b.inStacks
-	a.inWorkBufs += b.inWorkBufs
-	a.inPtrScalarBits += b.inPtrScalarBits
-
-	a.tinyAllocCount += b.tinyAllocCount
-	a.largeAlloc += b.largeAlloc
-	a.largeAllocCount += b.largeAllocCount
-	for i := range b.smallAllocCount {
-		a.smallAllocCount[i] += b.smallAllocCount[i]
-	}
-	a.largeFree += b.largeFree
-	a.largeFreeCount += b.largeFreeCount
-	for i := range b.smallFreeCount {
-		a.smallFreeCount[i] += b.smallFreeCount[i]
-	}
-}
-
-// consistentHeapStats represents a set of various memory statistics
-// whose updates must be viewed completely to get a consistent
-// state of the world.
-//
-// To write updates to memory stats use the acquire and release
-// methods. To obtain a consistent global snapshot of these statistics,
-// use read.
-type consistentHeapStats struct {
-	// stats is a ring buffer of heapStatsDelta values.
-	// Writers always atomically update the delta at index gen.
-	//
-	// Readers operate by rotating gen (0 -> 1 -> 2 -> 0 -> ...)
-	// and synchronizing with writers by observing each P's
-	// statsSeq field. If the reader observes a P not writing,
-	// it can be sure that it will pick up the new gen value the
-	// next time it writes.
-	//
-	// The reader then takes responsibility by clearing space
-	// in the ring buffer for the next reader to rotate gen to
-	// that space (i.e. it merges in values from index (gen-2) mod 3
-	// to index (gen-1) mod 3, then clears the former).
-	//
-	// Note that this means only one reader can be reading at a time.
-	// There is no way for readers to synchronize.
-	//
-	// This process is why we need a ring buffer of size 3 instead
-	// of 2: one is for the writers, one contains the most recent
-	// data, and the last one is clear so writers can begin writing
-	// to it the moment gen is updated.
-	stats [3]heapStatsDelta
-
-	// gen represents the current index into which writers
-	// are writing, and can take on the value of 0, 1, or 2.
-	// This value is updated atomically.
-	gen uint32
-
-	// noPLock is intended to provide mutual exclusion for updating
-	// stats when no P is available. It does not block other writers
-	// with a P, only other writers without a P and the reader. Because
-	// stats are usually updated when a P is available, contention on
-	// this lock should be minimal.
-	noPLock mutex
-}
-
-// acquire returns a heapStatsDelta to be updated. In effect,
-// it acquires the shard for writing. release must be called
-// as soon as the relevant deltas are updated.
-//
-// The returned heapStatsDelta must be updated atomically.
-//
-// The caller's P must not change between acquire and
-// release. This also means that the caller should not
-// acquire a P or release its P in between. A P also must
-// not acquire a given consistentHeapStats if it hasn't
-// yet released it.
-//
-// nosplit because a stack growth in this function could
-// lead to a stack allocation that could reenter the
-// function.
-//
-//go:nosplit
-func (m *consistentHeapStats) acquire() *heapStatsDelta {
-	if pp := getg().m.p.ptr(); pp != nil {
-		seq := atomic.Xadd(&pp.statsSeq, 1)
-		if seq%2 == 0 {
-			// Should have been incremented to odd.
-			print("runtime: seq=", seq, "\n")
-			throw("bad sequence number")
-		}
-	} else {
-		lock(&m.noPLock)
-	}
-	gen := atomic.Load(&m.gen) % 3
-	return &m.stats[gen]
-}
-
-// release indicates that the writer is done modifying
-// the delta. The value returned by the corresponding
-// acquire must no longer be accessed or modified after
-// release is called.
-//
-// The caller's P must not change between acquire and
-// release. This also means that the caller should not
-// acquire a P or release its P in between.
-//
-// nosplit because a stack growth in this function could
-// lead to a stack allocation that causes another acquire
-// before this operation has completed.
-//
-//go:nosplit
-func (m *consistentHeapStats) release() {
-	if pp := getg().m.p.ptr(); pp != nil {
-		seq := atomic.Xadd(&pp.statsSeq, 1)
-		if seq%2 != 0 {
-			// Should have been incremented to even.
-			print("runtime: seq=", seq, "\n")
-			throw("bad sequence number")
-		}
-	} else {
-		unlock(&m.noPLock)
-	}
-}
-
-// unsafeRead aggregates the delta for this shard into out.
-//
-// Unsafe because it does so without any synchronization. The
-// world must be stopped.
-func (m *consistentHeapStats) unsafeRead(out *heapStatsDelta) {
-	assertWorldStopped()
-
-	for i := range m.stats {
-		out.merge(&m.stats[i])
-	}
-}
-
-// unsafeClear clears the shard.
-//
-// Unsafe because the world must be stopped and values should
-// be donated elsewhere before clearing.
-func (m *consistentHeapStats) unsafeClear() {
-	assertWorldStopped()
-
-	for i := range m.stats {
-		m.stats[i] = heapStatsDelta{}
-	}
-}
-
-// read takes a globally consistent snapshot of m
-// and puts the aggregated value in out. Even though out is a
-// heapStatsDelta, the resulting values should be complete and
-// valid statistic values.
-//
-// Not safe to call concurrently. The world must be stopped
-// or metricsSema must be held.
-func (m *consistentHeapStats) read(out *heapStatsDelta) {
-	// Getting preempted after this point is not safe because
-	// we read allp. We need to make sure a STW can't happen
-	// so it doesn't change out from under us.
-	mp := acquirem()
-
-	// Get the current generation. We can be confident that this
-	// will not change since read is serialized and is the only
-	// one that modifies currGen.
-	currGen := atomic.Load(&m.gen)
-	prevGen := currGen - 1
-	if currGen == 0 {
-		prevGen = 2
-	}
-
-	// Prevent writers without a P from writing while we update gen.
-	lock(&m.noPLock)
-
-	// Rotate gen, effectively taking a snapshot of the state of
-	// these statistics at the point of the exchange by moving
-	// writers to the next set of deltas.
-	//
-	// This exchange is safe to do because we won't race
-	// with anyone else trying to update this value.
-	atomic.Xchg(&m.gen, (currGen+1)%3)
-
-	// Allow P-less writers to continue. They'll be writing to the
-	// next generation now.
-	unlock(&m.noPLock)
-
-	for _, p := range allp {
-		// Spin until there are no more writers.
-		for atomic.Load(&p.statsSeq)%2 != 0 {
-		}
-	}
-
-	// At this point we've observed that each sequence
-	// number is even, so any future writers will observe
-	// the new gen value. That means it's safe to read from
-	// the other deltas in the stats buffer.
-
-	// Perform our responsibilities and free up
-	// stats[prevGen] for the next time we want to take
-	// a snapshot.
-	m.stats[currGen].merge(&m.stats[prevGen])
-	m.stats[prevGen] = heapStatsDelta{}
-
-	// Finally, copy out the complete delta.
-	*out = m.stats[currGen]
-
-	releasem(mp)
-}
diff --git a/contrib/go/_std_1.18/src/runtime/mwbbuf.go b/contrib/go/_std_1.18/src/runtime/mwbbuf.go
deleted file mode 100644
index 78d9382620..0000000000
--- a/contrib/go/_std_1.18/src/runtime/mwbbuf.go
+++ /dev/null
@@ -1,290 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This implements the write barrier buffer. The write barrier itself
-// is gcWriteBarrier and is implemented in assembly.
-//
-// See mbarrier.go for algorithmic details on the write barrier. This
-// file deals only with the buffer.
-//
-// The write barrier has a fast path and a slow path. The fast path
-// simply enqueues to a per-P write barrier buffer. It's written in
-// assembly and doesn't clobber any general purpose registers, so it
-// doesn't have the usual overheads of a Go call.
-//
-// When the buffer fills up, the write barrier invokes the slow path
-// (wbBufFlush) to flush the buffer to the GC work queues. In this
-// path, since the compiler didn't spill registers, we spill *all*
-// registers and disallow any GC safe points that could observe the
-// stack frame (since we don't know the types of the spilled
-// registers).
-
-package runtime
-
-import (
-	"internal/goarch"
-	"runtime/internal/atomic"
-	"unsafe"
-)
-
-// testSmallBuf forces a small write barrier buffer to stress write
-// barrier flushing.
-const testSmallBuf = false
-
-// wbBuf is a per-P buffer of pointers queued by the write barrier.
-// This buffer is flushed to the GC workbufs when it fills up and on
-// various GC transitions.
-//
-// This is closely related to a "sequential store buffer" (SSB),
-// except that SSBs are usually used for maintaining remembered sets,
-// while this is used for marking.
-type wbBuf struct {
-	// next points to the next slot in buf. It must not be a
-	// pointer type because it can point past the end of buf and
-	// must be updated without write barriers.
-	//
-	// This is a pointer rather than an index to optimize the
-	// write barrier assembly.
-	next uintptr
-
-	// end points to just past the end of buf. It must not be a
-	// pointer type because it points past the end of buf and must
-	// be updated without write barriers.
-	end uintptr
-
-	// buf stores a series of pointers to execute write barriers
-	// on. This must be a multiple of wbBufEntryPointers because
-	// the write barrier only checks for overflow once per entry.
-	buf [wbBufEntryPointers * wbBufEntries]uintptr
-}
-
-const (
-	// wbBufEntries is the number of write barriers between
-	// flushes of the write barrier buffer.
-	//
-	// This trades latency for throughput amortization. Higher
-	// values amortize flushing overhead more, but increase the
-	// latency of flushing. Higher values also increase the cache
-	// footprint of the buffer.
-	//
-	// TODO: What is the latency cost of this? Tune this value.
-	wbBufEntries = 256
-
-	// wbBufEntryPointers is the number of pointers added to the
-	// buffer by each write barrier.
-	wbBufEntryPointers = 2
-)
-
-// reset empties b by resetting its next and end pointers.
-func (b *wbBuf) reset() {
-	start := uintptr(unsafe.Pointer(&b.buf[0]))
-	b.next = start
-	if writeBarrier.cgo {
-		// Effectively disable the buffer by forcing a flush
-		// on every barrier.
-		b.end = uintptr(unsafe.Pointer(&b.buf[wbBufEntryPointers]))
-	} else if testSmallBuf {
-		// For testing, allow two barriers in the buffer. If
-		// we only did one, then barriers of non-heap pointers
-		// would be no-ops. This lets us combine a buffered
-		// barrier with a flush at a later time.
-		b.end = uintptr(unsafe.Pointer(&b.buf[2*wbBufEntryPointers]))
-	} else {
-		b.end = start + uintptr(len(b.buf))*unsafe.Sizeof(b.buf[0])
-	}
-
-	if (b.end-b.next)%(wbBufEntryPointers*unsafe.Sizeof(b.buf[0])) != 0 {
-		throw("bad write barrier buffer bounds")
-	}
-}
-
-// discard resets b's next pointer, but not its end pointer.
-//
-// This must be nosplit because it's called by wbBufFlush.
-//
-//go:nosplit
-func (b *wbBuf) discard() {
-	b.next = uintptr(unsafe.Pointer(&b.buf[0]))
-}
-
-// empty reports whether b contains no pointers.
-func (b *wbBuf) empty() bool {
-	return b.next == uintptr(unsafe.Pointer(&b.buf[0]))
-}
-
-// putFast adds old and new to the write barrier buffer and returns
-// false if a flush is necessary. Callers should use this as:
-//
-//     buf := &getg().m.p.ptr().wbBuf
-//     if !buf.putFast(old, new) {
-//         wbBufFlush(...)
-//     }
-//     ... actual memory write ...
-//
-// The arguments to wbBufFlush depend on whether the caller is doing
-// its own cgo pointer checks. If it is, then this can be
-// wbBufFlush(nil, 0). Otherwise, it must pass the slot address and
-// new.
-//
-// The caller must ensure there are no preemption points during the
-// above sequence. There must be no preemption points while buf is in
-// use because it is a per-P resource. There must be no preemption
-// points between the buffer put and the write to memory because this
-// could allow a GC phase change, which could result in missed write
-// barriers.
-//
-// putFast must be nowritebarrierrec to because write barriers here would
-// corrupt the write barrier buffer. It (and everything it calls, if
-// it called anything) has to be nosplit to avoid scheduling on to a
-// different P and a different buffer.
-//
-//go:nowritebarrierrec
-//go:nosplit
-func (b *wbBuf) putFast(old, new uintptr) bool {
-	p := (*[2]uintptr)(unsafe.Pointer(b.next))
-	p[0] = old
-	p[1] = new
-	b.next += 2 * goarch.PtrSize
-	return b.next != b.end
-}
-
-// wbBufFlush flushes the current P's write barrier buffer to the GC
-// workbufs. It is passed the slot and value of the write barrier that
-// caused the flush so that it can implement cgocheck.
-//
-// This must not have write barriers because it is part of the write
-// barrier implementation.
-//
-// This and everything it calls must be nosplit because 1) the stack
-// contains untyped slots from gcWriteBarrier and 2) there must not be
-// a GC safe point between the write barrier test in the caller and
-// flushing the buffer.
-//
-// TODO: A "go:nosplitrec" annotation would be perfect for this.
-//
-//go:nowritebarrierrec
-//go:nosplit
-func wbBufFlush(dst *uintptr, src uintptr) {
-	// Note: Every possible return from this function must reset
-	// the buffer's next pointer to prevent buffer overflow.
-
-	// This *must not* modify its arguments because this
-	// function's argument slots do double duty in gcWriteBarrier
-	// as register spill slots. Currently, not modifying the
-	// arguments is sufficient to keep the spill slots unmodified
-	// (which seems unlikely to change since it costs little and
-	// helps with debugging).
-
-	if getg().m.dying > 0 {
-		// We're going down. Not much point in write barriers
-		// and this way we can allow write barriers in the
-		// panic path.
-		getg().m.p.ptr().wbBuf.discard()
-		return
-	}
-
-	if writeBarrier.cgo && dst != nil {
-		// This must be called from the stack that did the
-		// write. It's nosplit all the way down.
-		cgoCheckWriteBarrier(dst, src)
-		if !writeBarrier.needed {
-			// We were only called for cgocheck.
-			getg().m.p.ptr().wbBuf.discard()
-			return
-		}
-	}
-
-	// Switch to the system stack so we don't have to worry about
-	// the untyped stack slots or safe points.
-	systemstack(func() {
-		wbBufFlush1(getg().m.p.ptr())
-	})
-}
-
-// wbBufFlush1 flushes p's write barrier buffer to the GC work queue.
-//
-// This must not have write barriers because it is part of the write
-// barrier implementation, so this may lead to infinite loops or
-// buffer corruption.
-//
-// This must be non-preemptible because it uses the P's workbuf.
-//
-//go:nowritebarrierrec
-//go:systemstack
-func wbBufFlush1(_p_ *p) {
-	// Get the buffered pointers.
-	start := uintptr(unsafe.Pointer(&_p_.wbBuf.buf[0]))
-	n := (_p_.wbBuf.next - start) / unsafe.Sizeof(_p_.wbBuf.buf[0])
-	ptrs := _p_.wbBuf.buf[:n]
-
-	// Poison the buffer to make extra sure nothing is enqueued
-	// while we're processing the buffer.
-	_p_.wbBuf.next = 0
-
-	if useCheckmark {
-		// Slow path for checkmark mode.
-		for _, ptr := range ptrs {
-			shade(ptr)
-		}
-		_p_.wbBuf.reset()
-		return
-	}
-
-	// Mark all of the pointers in the buffer and record only the
-	// pointers we greyed. We use the buffer itself to temporarily
-	// record greyed pointers.
-	//
-	// TODO: Should scanobject/scanblock just stuff pointers into
-	// the wbBuf? Then this would become the sole greying path.
-	//
-	// TODO: We could avoid shading any of the "new" pointers in
-	// the buffer if the stack has been shaded, or even avoid
-	// putting them in the buffer at all (which would double its
-	// capacity). This is slightly complicated with the buffer; we
-	// could track whether any un-shaded goroutine has used the
-	// buffer, or just track globally whether there are any
-	// un-shaded stacks and flush after each stack scan.
-	gcw := &_p_.gcw
-	pos := 0
-	for _, ptr := range ptrs {
-		if ptr < minLegalPointer {
-			// nil pointers are very common, especially
-			// for the "old" values. Filter out these and
-			// other "obvious" non-heap pointers ASAP.
-			//
-			// TODO: Should we filter out nils in the fast
-			// path to reduce the rate of flushes?
-			continue
-		}
-		obj, span, objIndex := findObject(ptr, 0, 0)
-		if obj == 0 {
-			continue
-		}
-		// TODO: Consider making two passes where the first
-		// just prefetches the mark bits.
-		mbits := span.markBitsForIndex(objIndex)
-		if mbits.isMarked() {
-			continue
-		}
-		mbits.setMarked()
-
-		// Mark span.
-		arena, pageIdx, pageMask := pageIndexOf(span.base())
-		if arena.pageMarks[pageIdx]&pageMask == 0 {
-			atomic.Or8(&arena.pageMarks[pageIdx], pageMask)
-		}
-
-		if span.spanclass.noscan() {
-			gcw.bytesMarked += uint64(span.elemsize)
-			continue
-		}
-		ptrs[pos] = obj
-		pos++
-	}
-
-	// Enqueue the greyed objects.
-	gcw.putBatch(ptrs[:pos])
-
-	_p_.wbBuf.reset()
-}
diff --git a/contrib/go/_std_1.18/src/runtime/nbpipe_pipe2.go b/contrib/go/_std_1.18/src/runtime/nbpipe_pipe2.go
deleted file mode 100644
index 6a555bcd99..0000000000
--- a/contrib/go/_std_1.18/src/runtime/nbpipe_pipe2.go
+++ /dev/null
@@ -1,22 +0,0 @@
-// Copyright 2019 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build dragonfly || freebsd || linux || netbsd || openbsd || solaris
-
-package runtime
-
-func nonblockingPipe() (r, w int32, errno int32) {
-	r, w, errno = pipe2(_O_NONBLOCK | _O_CLOEXEC)
-	if errno == -_ENOSYS {
-		r, w, errno = pipe()
-		if errno != 0 {
-			return -1, -1, errno
-		}
-		closeonexec(r)
-		setNonblock(r)
-		closeonexec(w)
-		setNonblock(w)
-	}
-	return r, w, errno
-}
diff --git a/contrib/go/_std_1.18/src/runtime/netpoll.go b/contrib/go/_std_1.18/src/runtime/netpoll.go
deleted file mode 100644
index bb3dd35317..0000000000
--- a/contrib/go/_std_1.18/src/runtime/netpoll.go
+++ /dev/null
@@ -1,652 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris || windows
-
-package runtime
-
-import (
-	"runtime/internal/atomic"
-	"unsafe"
-)
-
-// Integrated network poller (platform-independent part).
-// A particular implementation (epoll/kqueue/port/AIX/Windows)
-// must define the following functions:
-//
-// func netpollinit()
-//     Initialize the poller. Only called once.
-//
-// func netpollopen(fd uintptr, pd *pollDesc) int32
-//     Arm edge-triggered notifications for fd. The pd argument is to pass
-//     back to netpollready when fd is ready. Return an errno value.
-//
-// func netpollclose(fd uintptr) int32
-//     Disable notifications for fd. Return an errno value.
-//
-// func netpoll(delta int64) gList
-//     Poll the network. If delta < 0, block indefinitely. If delta == 0,
-//     poll without blocking. If delta > 0, block for up to delta nanoseconds.
-//     Return a list of goroutines built by calling netpollready.
-//
-// func netpollBreak()
-//     Wake up the network poller, assumed to be blocked in netpoll.
-//
-// func netpollIsPollDescriptor(fd uintptr) bool
-//     Reports whether fd is a file descriptor used by the poller.
-
-// Error codes returned by runtime_pollReset and runtime_pollWait.
-// These must match the values in internal/poll/fd_poll_runtime.go.
-const (
-	pollNoError        = 0 // no error
-	pollErrClosing     = 1 // descriptor is closed
-	pollErrTimeout     = 2 // I/O timeout
-	pollErrNotPollable = 3 // general error polling descriptor
-)
-
-// pollDesc contains 2 binary semaphores, rg and wg, to park reader and writer
-// goroutines respectively. The semaphore can be in the following states:
-// pdReady - io readiness notification is pending;
-//           a goroutine consumes the notification by changing the state to nil.
-// pdWait - a goroutine prepares to park on the semaphore, but not yet parked;
-//          the goroutine commits to park by changing the state to G pointer,
-//          or, alternatively, concurrent io notification changes the state to pdReady,
-//          or, alternatively, concurrent timeout/close changes the state to nil.
-// G pointer - the goroutine is blocked on the semaphore;
-//             io notification or timeout/close changes the state to pdReady or nil respectively
-//             and unparks the goroutine.
-// nil - none of the above.
-const (
-	pdReady uintptr = 1
-	pdWait  uintptr = 2
-)
-
-const pollBlockSize = 4 * 1024
-
-// Network poller descriptor.
-//
-// No heap pointers.
-//
-//go:notinheap
-type pollDesc struct {
-	link *pollDesc // in pollcache, protected by pollcache.lock
-	fd   uintptr   // constant for pollDesc usage lifetime
-
-	// atomicInfo holds bits from closing, rd, and wd,
-	// which are only ever written while holding the lock,
-	// summarized for use by netpollcheckerr,
-	// which cannot acquire the lock.
-	// After writing these fields under lock in a way that
-	// might change the summary, code must call publishInfo
-	// before releasing the lock.
-	// Code that changes fields and then calls netpollunblock
-	// (while still holding the lock) must call publishInfo
-	// before calling netpollunblock, because publishInfo is what
-	// stops netpollblock from blocking anew
-	// (by changing the result of netpollcheckerr).
-	// atomicInfo also holds the eventErr bit,
-	// recording whether a poll event on the fd got an error;
-	// atomicInfo is the only source of truth for that bit.
-	atomicInfo atomic.Uint32 // atomic pollInfo
-
-	// rg, wg are accessed atomically and hold g pointers.
-	// (Using atomic.Uintptr here is similar to using guintptr elsewhere.)
-	rg atomic.Uintptr // pdReady, pdWait, G waiting for read or nil
-	wg atomic.Uintptr // pdReady, pdWait, G waiting for write or nil
-
-	lock    mutex // protects the following fields
-	closing bool
-	user    uint32    // user settable cookie
-	rseq    uintptr   // protects from stale read timers
-	rt      timer     // read deadline timer (set if rt.f != nil)
-	rd      int64     // read deadline (a nanotime in the future, -1 when expired)
-	wseq    uintptr   // protects from stale write timers
-	wt      timer     // write deadline timer
-	wd      int64     // write deadline (a nanotime in the future, -1 when expired)
-	self    *pollDesc // storage for indirect interface. See (*pollDesc).makeArg.
-}
-
-// pollInfo is the bits needed by netpollcheckerr, stored atomically,
-// mostly duplicating state that is manipulated under lock in pollDesc.
-// The one exception is the pollEventErr bit, which is maintained only
-// in the pollInfo.
-type pollInfo uint32
-
-const (
-	pollClosing = 1 << iota
-	pollEventErr
-	pollExpiredReadDeadline
-	pollExpiredWriteDeadline
-)
-
-func (i pollInfo) closing() bool              { return i&pollClosing != 0 }
-func (i pollInfo) eventErr() bool             { return i&pollEventErr != 0 }
-func (i pollInfo) expiredReadDeadline() bool  { return i&pollExpiredReadDeadline != 0 }
-func (i pollInfo) expiredWriteDeadline() bool { return i&pollExpiredWriteDeadline != 0 }
-
-// info returns the pollInfo corresponding to pd.
-func (pd *pollDesc) info() pollInfo {
-	return pollInfo(pd.atomicInfo.Load())
-}
-
-// publishInfo updates pd.atomicInfo (returned by pd.info)
-// using the other values in pd.
-// It must be called while holding pd.lock,
-// and it must be called after changing anything
-// that might affect the info bits.
-// In practice this means after changing closing
-// or changing rd or wd from < 0 to >= 0.
-func (pd *pollDesc) publishInfo() {
-	var info uint32
-	if pd.closing {
-		info |= pollClosing
-	}
-	if pd.rd < 0 {
-		info |= pollExpiredReadDeadline
-	}
-	if pd.wd < 0 {
-		info |= pollExpiredWriteDeadline
-	}
-
-	// Set all of x except the pollEventErr bit.
-	x := pd.atomicInfo.Load()
-	for !pd.atomicInfo.CompareAndSwap(x, (x&pollEventErr)|info) {
-		x = pd.atomicInfo.Load()
-	}
-}
-
-// setEventErr sets the result of pd.info().eventErr() to b.
-func (pd *pollDesc) setEventErr(b bool) {
-	x := pd.atomicInfo.Load()
-	for (x&pollEventErr != 0) != b && !pd.atomicInfo.CompareAndSwap(x, x^pollEventErr) {
-		x = pd.atomicInfo.Load()
-	}
-}
-
-type pollCache struct {
-	lock  mutex
-	first *pollDesc
-	// PollDesc objects must be type-stable,
-	// because we can get ready notification from epoll/kqueue
-	// after the descriptor is closed/reused.
-	// Stale notifications are detected using seq variable,
-	// seq is incremented when deadlines are changed or descriptor is reused.
-}
-
-var (
-	netpollInitLock mutex
-	netpollInited   uint32
-
-	pollcache      pollCache
-	netpollWaiters uint32
-)
-
-//go:linkname poll_runtime_pollServerInit internal/poll.runtime_pollServerInit
-func poll_runtime_pollServerInit() {
-	netpollGenericInit()
-}
-
-func netpollGenericInit() {
-	if atomic.Load(&netpollInited) == 0 {
-		lockInit(&netpollInitLock, lockRankNetpollInit)
-		lock(&netpollInitLock)
-		if netpollInited == 0 {
-			netpollinit()
-			atomic.Store(&netpollInited, 1)
-		}
-		unlock(&netpollInitLock)
-	}
-}
-
-func netpollinited() bool {
-	return atomic.Load(&netpollInited) != 0
-}
-
-//go:linkname poll_runtime_isPollServerDescriptor internal/poll.runtime_isPollServerDescriptor
-
-// poll_runtime_isPollServerDescriptor reports whether fd is a
-// descriptor being used by netpoll.
-func poll_runtime_isPollServerDescriptor(fd uintptr) bool {
-	return netpollIsPollDescriptor(fd)
-}
-
-//go:linkname poll_runtime_pollOpen internal/poll.runtime_pollOpen
-func poll_runtime_pollOpen(fd uintptr) (*pollDesc, int) {
-	pd := pollcache.alloc()
-	lock(&pd.lock)
-	wg := pd.wg.Load()
-	if wg != 0 && wg != pdReady {
-		throw("runtime: blocked write on free polldesc")
-	}
-	rg := pd.rg.Load()
-	if rg != 0 && rg != pdReady {
-		throw("runtime: blocked read on free polldesc")
-	}
-	pd.fd = fd
-	pd.closing = false
-	pd.setEventErr(false)
-	pd.rseq++
-	pd.rg.Store(0)
-	pd.rd = 0
-	pd.wseq++
-	pd.wg.Store(0)
-	pd.wd = 0
-	pd.self = pd
-	pd.publishInfo()
-	unlock(&pd.lock)
-
-	errno := netpollopen(fd, pd)
-	if errno != 0 {
-		pollcache.free(pd)
-		return nil, int(errno)
-	}
-	return pd, 0
-}
-
-//go:linkname poll_runtime_pollClose internal/poll.runtime_pollClose
-func poll_runtime_pollClose(pd *pollDesc) {
-	if !pd.closing {
-		throw("runtime: close polldesc w/o unblock")
-	}
-	wg := pd.wg.Load()
-	if wg != 0 && wg != pdReady {
-		throw("runtime: blocked write on closing polldesc")
-	}
-	rg := pd.rg.Load()
-	if rg != 0 && rg != pdReady {
-		throw("runtime: blocked read on closing polldesc")
-	}
-	netpollclose(pd.fd)
-	pollcache.free(pd)
-}
-
-func (c *pollCache) free(pd *pollDesc) {
-	lock(&c.lock)
-	pd.link = c.first
-	c.first = pd
-	unlock(&c.lock)
-}
-
-// poll_runtime_pollReset, which is internal/poll.runtime_pollReset,
-// prepares a descriptor for polling in mode, which is 'r' or 'w'.
-// This returns an error code; the codes are defined above.
-//go:linkname poll_runtime_pollReset internal/poll.runtime_pollReset
-func poll_runtime_pollReset(pd *pollDesc, mode int) int {
-	errcode := netpollcheckerr(pd, int32(mode))
-	if errcode != pollNoError {
-		return errcode
-	}
-	if mode == 'r' {
-		pd.rg.Store(0)
-	} else if mode == 'w' {
-		pd.wg.Store(0)
-	}
-	return pollNoError
-}
-
-// poll_runtime_pollWait, which is internal/poll.runtime_pollWait,
-// waits for a descriptor to be ready for reading or writing,
-// according to mode, which is 'r' or 'w'.
-// This returns an error code; the codes are defined above.
-//go:linkname poll_runtime_pollWait internal/poll.runtime_pollWait
-func poll_runtime_pollWait(pd *pollDesc, mode int) int {
-	errcode := netpollcheckerr(pd, int32(mode))
-	if errcode != pollNoError {
-		return errcode
-	}
-	// As for now only Solaris, illumos, and AIX use level-triggered IO.
-	if GOOS == "solaris" || GOOS == "illumos" || GOOS == "aix" {
-		netpollarm(pd, mode)
-	}
-	for !netpollblock(pd, int32(mode), false) {
-		errcode = netpollcheckerr(pd, int32(mode))
-		if errcode != pollNoError {
-			return errcode
-		}
-		// Can happen if timeout has fired and unblocked us,
-		// but before we had a chance to run, timeout has been reset.
-		// Pretend it has not happened and retry.
-	}
-	return pollNoError
-}
-
-//go:linkname poll_runtime_pollWaitCanceled internal/poll.runtime_pollWaitCanceled
-func poll_runtime_pollWaitCanceled(pd *pollDesc, mode int) {
-	// This function is used only on windows after a failed attempt to cancel
-	// a pending async IO operation. Wait for ioready, ignore closing or timeouts.
-	for !netpollblock(pd, int32(mode), true) {
-	}
-}
-
-//go:linkname poll_runtime_pollSetDeadline internal/poll.runtime_pollSetDeadline
-func poll_runtime_pollSetDeadline(pd *pollDesc, d int64, mode int) {
-	lock(&pd.lock)
-	if pd.closing {
-		unlock(&pd.lock)
-		return
-	}
-	rd0, wd0 := pd.rd, pd.wd
-	combo0 := rd0 > 0 && rd0 == wd0
-	if d > 0 {
-		d += nanotime()
-		if d <= 0 {
-			// If the user has a deadline in the future, but the delay calculation
-			// overflows, then set the deadline to the maximum possible value.
-			d = 1<<63 - 1
-		}
-	}
-	if mode == 'r' || mode == 'r'+'w' {
-		pd.rd = d
-	}
-	if mode == 'w' || mode == 'r'+'w' {
-		pd.wd = d
-	}
-	pd.publishInfo()
-	combo := pd.rd > 0 && pd.rd == pd.wd
-	rtf := netpollReadDeadline
-	if combo {
-		rtf = netpollDeadline
-	}
-	if pd.rt.f == nil {
-		if pd.rd > 0 {
-			pd.rt.f = rtf
-			// Copy current seq into the timer arg.
-			// Timer func will check the seq against current descriptor seq,
-			// if they differ the descriptor was reused or timers were reset.
-			pd.rt.arg = pd.makeArg()
-			pd.rt.seq = pd.rseq
-			resettimer(&pd.rt, pd.rd)
-		}
-	} else if pd.rd != rd0 || combo != combo0 {
-		pd.rseq++ // invalidate current timers
-		if pd.rd > 0 {
-			modtimer(&pd.rt, pd.rd, 0, rtf, pd.makeArg(), pd.rseq)
-		} else {
-			deltimer(&pd.rt)
-			pd.rt.f = nil
-		}
-	}
-	if pd.wt.f == nil {
-		if pd.wd > 0 && !combo {
-			pd.wt.f = netpollWriteDeadline
-			pd.wt.arg = pd.makeArg()
-			pd.wt.seq = pd.wseq
-			resettimer(&pd.wt, pd.wd)
-		}
-	} else if pd.wd != wd0 || combo != combo0 {
-		pd.wseq++ // invalidate current timers
-		if pd.wd > 0 && !combo {
-			modtimer(&pd.wt, pd.wd, 0, netpollWriteDeadline, pd.makeArg(), pd.wseq)
-		} else {
-			deltimer(&pd.wt)
-			pd.wt.f = nil
-		}
-	}
-	// If we set the new deadline in the past, unblock currently pending IO if any.
-	// Note that pd.publishInfo has already been called, above, immediately after modifying rd and wd.
-	var rg, wg *g
-	if pd.rd < 0 {
-		rg = netpollunblock(pd, 'r', false)
-	}
-	if pd.wd < 0 {
-		wg = netpollunblock(pd, 'w', false)
-	}
-	unlock(&pd.lock)
-	if rg != nil {
-		netpollgoready(rg, 3)
-	}
-	if wg != nil {
-		netpollgoready(wg, 3)
-	}
-}
-
-//go:linkname poll_runtime_pollUnblock internal/poll.runtime_pollUnblock
-func poll_runtime_pollUnblock(pd *pollDesc) {
-	lock(&pd.lock)
-	if pd.closing {
-		throw("runtime: unblock on closing polldesc")
-	}
-	pd.closing = true
-	pd.rseq++
-	pd.wseq++
-	var rg, wg *g
-	pd.publishInfo()
-	rg = netpollunblock(pd, 'r', false)
-	wg = netpollunblock(pd, 'w', false)
-	if pd.rt.f != nil {
-		deltimer(&pd.rt)
-		pd.rt.f = nil
-	}
-	if pd.wt.f != nil {
-		deltimer(&pd.wt)
-		pd.wt.f = nil
-	}
-	unlock(&pd.lock)
-	if rg != nil {
-		netpollgoready(rg, 3)
-	}
-	if wg != nil {
-		netpollgoready(wg, 3)
-	}
-}
-
-// netpollready is called by the platform-specific netpoll function.
-// It declares that the fd associated with pd is ready for I/O.
-// The toRun argument is used to build a list of goroutines to return
-// from netpoll. The mode argument is 'r', 'w', or 'r'+'w' to indicate
-// whether the fd is ready for reading or writing or both.
-//
-// This may run while the world is stopped, so write barriers are not allowed.
-//go:nowritebarrier
-func netpollready(toRun *gList, pd *pollDesc, mode int32) {
-	var rg, wg *g
-	if mode == 'r' || mode == 'r'+'w' {
-		rg = netpollunblock(pd, 'r', true)
-	}
-	if mode == 'w' || mode == 'r'+'w' {
-		wg = netpollunblock(pd, 'w', true)
-	}
-	if rg != nil {
-		toRun.push(rg)
-	}
-	if wg != nil {
-		toRun.push(wg)
-	}
-}
-
-func netpollcheckerr(pd *pollDesc, mode int32) int {
-	info := pd.info()
-	if info.closing() {
-		return pollErrClosing
-	}
-	if (mode == 'r' && info.expiredReadDeadline()) || (mode == 'w' && info.expiredWriteDeadline()) {
-		return pollErrTimeout
-	}
-	// Report an event scanning error only on a read event.
-	// An error on a write event will be captured in a subsequent
-	// write call that is able to report a more specific error.
-	if mode == 'r' && info.eventErr() {
-		return pollErrNotPollable
-	}
-	return pollNoError
-}
-
-func netpollblockcommit(gp *g, gpp unsafe.Pointer) bool {
-	r := atomic.Casuintptr((*uintptr)(gpp), pdWait, uintptr(unsafe.Pointer(gp)))
-	if r {
-		// Bump the count of goroutines waiting for the poller.
-		// The scheduler uses this to decide whether to block
-		// waiting for the poller if there is nothing else to do.
-		atomic.Xadd(&netpollWaiters, 1)
-	}
-	return r
-}
-
-func netpollgoready(gp *g, traceskip int) {
-	atomic.Xadd(&netpollWaiters, -1)
-	goready(gp, traceskip+1)
-}
-
-// returns true if IO is ready, or false if timedout or closed
-// waitio - wait only for completed IO, ignore errors
-// Concurrent calls to netpollblock in the same mode are forbidden, as pollDesc
-// can hold only a single waiting goroutine for each mode.
-func netpollblock(pd *pollDesc, mode int32, waitio bool) bool {
-	gpp := &pd.rg
-	if mode == 'w' {
-		gpp = &pd.wg
-	}
-
-	// set the gpp semaphore to pdWait
-	for {
-		// Consume notification if already ready.
-		if gpp.CompareAndSwap(pdReady, 0) {
-			return true
-		}
-		if gpp.CompareAndSwap(0, pdWait) {
-			break
-		}
-
-		// Double check that this isn't corrupt; otherwise we'd loop
-		// forever.
-		if v := gpp.Load(); v != pdReady && v != 0 {
-			throw("runtime: double wait")
-		}
-	}
-
-	// need to recheck error states after setting gpp to pdWait
-	// this is necessary because runtime_pollUnblock/runtime_pollSetDeadline/deadlineimpl
-	// do the opposite: store to closing/rd/wd, publishInfo, load of rg/wg
-	if waitio || netpollcheckerr(pd, mode) == pollNoError {
-		gopark(netpollblockcommit, unsafe.Pointer(gpp), waitReasonIOWait, traceEvGoBlockNet, 5)
-	}
-	// be careful to not lose concurrent pdReady notification
-	old := gpp.Swap(0)
-	if old > pdWait {
-		throw("runtime: corrupted polldesc")
-	}
-	return old == pdReady
-}
-
-func netpollunblock(pd *pollDesc, mode int32, ioready bool) *g {
-	gpp := &pd.rg
-	if mode == 'w' {
-		gpp = &pd.wg
-	}
-
-	for {
-		old := gpp.Load()
-		if old == pdReady {
-			return nil
-		}
-		if old == 0 && !ioready {
-			// Only set pdReady for ioready. runtime_pollWait
-			// will check for timeout/cancel before waiting.
-			return nil
-		}
-		var new uintptr
-		if ioready {
-			new = pdReady
-		}
-		if gpp.CompareAndSwap(old, new) {
-			if old == pdWait {
-				old = 0
-			}
-			return (*g)(unsafe.Pointer(old))
-		}
-	}
-}
-
-func netpolldeadlineimpl(pd *pollDesc, seq uintptr, read, write bool) {
-	lock(&pd.lock)
-	// Seq arg is seq when the timer was set.
-	// If it's stale, ignore the timer event.
-	currentSeq := pd.rseq
-	if !read {
-		currentSeq = pd.wseq
-	}
-	if seq != currentSeq {
-		// The descriptor was reused or timers were reset.
-		unlock(&pd.lock)
-		return
-	}
-	var rg *g
-	if read {
-		if pd.rd <= 0 || pd.rt.f == nil {
-			throw("runtime: inconsistent read deadline")
-		}
-		pd.rd = -1
-		pd.publishInfo()
-		rg = netpollunblock(pd, 'r', false)
-	}
-	var wg *g
-	if write {
-		if pd.wd <= 0 || pd.wt.f == nil && !read {
-			throw("runtime: inconsistent write deadline")
-		}
-		pd.wd = -1
-		pd.publishInfo()
-		wg = netpollunblock(pd, 'w', false)
-	}
-	unlock(&pd.lock)
-	if rg != nil {
-		netpollgoready(rg, 0)
-	}
-	if wg != nil {
-		netpollgoready(wg, 0)
-	}
-}
-
-func netpollDeadline(arg any, seq uintptr) {
-	netpolldeadlineimpl(arg.(*pollDesc), seq, true, true)
-}
-
-func netpollReadDeadline(arg any, seq uintptr) {
-	netpolldeadlineimpl(arg.(*pollDesc), seq, true, false)
-}
-
-func netpollWriteDeadline(arg any, seq uintptr) {
-	netpolldeadlineimpl(arg.(*pollDesc), seq, false, true)
-}
-
-func (c *pollCache) alloc() *pollDesc {
-	lock(&c.lock)
-	if c.first == nil {
-		const pdSize = unsafe.Sizeof(pollDesc{})
-		n := pollBlockSize / pdSize
-		if n == 0 {
-			n = 1
-		}
-		// Must be in non-GC memory because can be referenced
-		// only from epoll/kqueue internals.
-		mem := persistentalloc(n*pdSize, 0, &memstats.other_sys)
-		for i := uintptr(0); i < n; i++ {
-			pd := (*pollDesc)(add(mem, i*pdSize))
-			pd.link = c.first
-			c.first = pd
-		}
-	}
-	pd := c.first
-	c.first = pd.link
-	lockInit(&pd.lock, lockRankPollDesc)
-	unlock(&c.lock)
-	return pd
-}
-
-// makeArg converts pd to an interface{}.
-// makeArg does not do any allocation. Normally, such
-// a conversion requires an allocation because pointers to
-// go:notinheap types (which pollDesc is) must be stored
-// in interfaces indirectly. See issue 42076.
-func (pd *pollDesc) makeArg() (i any) {
-	x := (*eface)(unsafe.Pointer(&i))
-	x._type = pdType
-	x.data = unsafe.Pointer(&pd.self)
-	return
-}
-
-var (
-	pdEface any    = (*pollDesc)(nil)
-	pdType  *_type = efaceOf(&pdEface)._type
-)
diff --git a/contrib/go/_std_1.18/src/runtime/os_darwin.go b/contrib/go/_std_1.18/src/runtime/os_darwin.go
deleted file mode 100644
index 9065b76375..0000000000
--- a/contrib/go/_std_1.18/src/runtime/os_darwin.go
+++ /dev/null
@@ -1,470 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"internal/abi"
-	"unsafe"
-)
-
-type mOS struct {
-	initialized bool
-	mutex       pthreadmutex
-	cond        pthreadcond
-	count       int
-}
-
-func unimplemented(name string) {
-	println(name, "not implemented")
-	*(*int)(unsafe.Pointer(uintptr(1231))) = 1231
-}
-
-//go:nosplit
-func semacreate(mp *m) {
-	if mp.initialized {
-		return
-	}
-	mp.initialized = true
-	if err := pthread_mutex_init(&mp.mutex, nil); err != 0 {
-		throw("pthread_mutex_init")
-	}
-	if err := pthread_cond_init(&mp.cond, nil); err != 0 {
-		throw("pthread_cond_init")
-	}
-}
-
-//go:nosplit
-func semasleep(ns int64) int32 {
-	var start int64
-	if ns >= 0 {
-		start = nanotime()
-	}
-	mp := getg().m
-	pthread_mutex_lock(&mp.mutex)
-	for {
-		if mp.count > 0 {
-			mp.count--
-			pthread_mutex_unlock(&mp.mutex)
-			return 0
-		}
-		if ns >= 0 {
-			spent := nanotime() - start
-			if spent >= ns {
-				pthread_mutex_unlock(&mp.mutex)
-				return -1
-			}
-			var t timespec
-			t.setNsec(ns - spent)
-			err := pthread_cond_timedwait_relative_np(&mp.cond, &mp.mutex, &t)
-			if err == _ETIMEDOUT {
-				pthread_mutex_unlock(&mp.mutex)
-				return -1
-			}
-		} else {
-			pthread_cond_wait(&mp.cond, &mp.mutex)
-		}
-	}
-}
-
-//go:nosplit
-func semawakeup(mp *m) {
-	pthread_mutex_lock(&mp.mutex)
-	mp.count++
-	if mp.count > 0 {
-		pthread_cond_signal(&mp.cond)
-	}
-	pthread_mutex_unlock(&mp.mutex)
-}
-
-// The read and write file descriptors used by the sigNote functions.
-var sigNoteRead, sigNoteWrite int32
-
-// sigNoteSetup initializes an async-signal-safe note.
-//
-// The current implementation of notes on Darwin is not async-signal-safe,
-// because the functions pthread_mutex_lock, pthread_cond_signal, and
-// pthread_mutex_unlock, called by semawakeup, are not async-signal-safe.
-// There is only one case where we need to wake up a note from a signal
-// handler: the sigsend function. The signal handler code does not require
-// all the features of notes: it does not need to do a timed wait.
-// This is a separate implementation of notes, based on a pipe, that does
-// not support timed waits but is async-signal-safe.
-func sigNoteSetup(*note) {
-	if sigNoteRead != 0 || sigNoteWrite != 0 {
-		throw("duplicate sigNoteSetup")
-	}
-	var errno int32
-	sigNoteRead, sigNoteWrite, errno = pipe()
-	if errno != 0 {
-		throw("pipe failed")
-	}
-	closeonexec(sigNoteRead)
-	closeonexec(sigNoteWrite)
-
-	// Make the write end of the pipe non-blocking, so that if the pipe
-	// buffer is somehow full we will not block in the signal handler.
-	// Leave the read end of the pipe blocking so that we will block
-	// in sigNoteSleep.
-	setNonblock(sigNoteWrite)
-}
-
-// sigNoteWakeup wakes up a thread sleeping on a note created by sigNoteSetup.
-func sigNoteWakeup(*note) {
-	var b byte
-	write(uintptr(sigNoteWrite), unsafe.Pointer(&b), 1)
-}
-
-// sigNoteSleep waits for a note created by sigNoteSetup to be woken.
-func sigNoteSleep(*note) {
-	for {
-		var b byte
-		entersyscallblock()
-		n := read(sigNoteRead, unsafe.Pointer(&b), 1)
-		exitsyscall()
-		if n != -_EINTR {
-			return
-		}
-	}
-}
-
-// BSD interface for threading.
-func osinit() {
-	// pthread_create delayed until end of goenvs so that we
-	// can look at the environment first.
-
-	ncpu = getncpu()
-	physPageSize = getPageSize()
-}
-
-func sysctlbynameInt32(name []byte) (int32, int32) {
-	out := int32(0)
-	nout := unsafe.Sizeof(out)
-	ret := sysctlbyname(&name[0], (*byte)(unsafe.Pointer(&out)), &nout, nil, 0)
-	return ret, out
-}
-
-//go:linkname internal_cpu_getsysctlbyname internal/cpu.getsysctlbyname
-func internal_cpu_getsysctlbyname(name []byte) (int32, int32) {
-	return sysctlbynameInt32(name)
-}
-
-const (
-	_CTL_HW      = 6
-	_HW_NCPU     = 3
-	_HW_PAGESIZE = 7
-)
-
-func getncpu() int32 {
-	// Use sysctl to fetch hw.ncpu.
-	mib := [2]uint32{_CTL_HW, _HW_NCPU}
-	out := uint32(0)
-	nout := unsafe.Sizeof(out)
-	ret := sysctl(&mib[0], 2, (*byte)(unsafe.Pointer(&out)), &nout, nil, 0)
-	if ret >= 0 && int32(out) > 0 {
-		return int32(out)
-	}
-	return 1
-}
-
-func getPageSize() uintptr {
-	// Use sysctl to fetch hw.pagesize.
-	mib := [2]uint32{_CTL_HW, _HW_PAGESIZE}
-	out := uint32(0)
-	nout := unsafe.Sizeof(out)
-	ret := sysctl(&mib[0], 2, (*byte)(unsafe.Pointer(&out)), &nout, nil, 0)
-	if ret >= 0 && int32(out) > 0 {
-		return uintptr(out)
-	}
-	return 0
-}
-
-var urandom_dev = []byte("/dev/urandom\x00")
-
-//go:nosplit
-func getRandomData(r []byte) {
-	fd := open(&urandom_dev[0], 0 /* O_RDONLY */, 0)
-	n := read(fd, unsafe.Pointer(&r[0]), int32(len(r)))
-	closefd(fd)
-	extendRandom(r, int(n))
-}
-
-func goenvs() {
-	goenvs_unix()
-}
-
-// May run with m.p==nil, so write barriers are not allowed.
-//go:nowritebarrierrec
-func newosproc(mp *m) {
-	stk := unsafe.Pointer(mp.g0.stack.hi)
-	if false {
-		print("newosproc stk=", stk, " m=", mp, " g=", mp.g0, " id=", mp.id, " ostk=", &mp, "\n")
-	}
-
-	// Initialize an attribute object.
-	var attr pthreadattr
-	var err int32
-	err = pthread_attr_init(&attr)
-	if err != 0 {
-		write(2, unsafe.Pointer(&failthreadcreate[0]), int32(len(failthreadcreate)))
-		exit(1)
-	}
-
-	// Find out OS stack size for our own stack guard.
-	var stacksize uintptr
-	if pthread_attr_getstacksize(&attr, &stacksize) != 0 {
-		write(2, unsafe.Pointer(&failthreadcreate[0]), int32(len(failthreadcreate)))
-		exit(1)
-	}
-	mp.g0.stack.hi = stacksize // for mstart
-
-	// Tell the pthread library we won't join with this thread.
-	if pthread_attr_setdetachstate(&attr, _PTHREAD_CREATE_DETACHED) != 0 {
-		write(2, unsafe.Pointer(&failthreadcreate[0]), int32(len(failthreadcreate)))
-		exit(1)
-	}
-
-	// Finally, create the thread. It starts at mstart_stub, which does some low-level
-	// setup and then calls mstart.
-	var oset sigset
-	sigprocmask(_SIG_SETMASK, &sigset_all, &oset)
-	err = pthread_create(&attr, abi.FuncPCABI0(mstart_stub), unsafe.Pointer(mp))
-	sigprocmask(_SIG_SETMASK, &oset, nil)
-	if err != 0 {
-		write(2, unsafe.Pointer(&failthreadcreate[0]), int32(len(failthreadcreate)))
-		exit(1)
-	}
-}
-
-// glue code to call mstart from pthread_create.
-func mstart_stub()
-
-// newosproc0 is a version of newosproc that can be called before the runtime
-// is initialized.
-//
-// This function is not safe to use after initialization as it does not pass an M as fnarg.
-//
-//go:nosplit
-func newosproc0(stacksize uintptr, fn uintptr) {
-	// Initialize an attribute object.
-	var attr pthreadattr
-	var err int32
-	err = pthread_attr_init(&attr)
-	if err != 0 {
-		write(2, unsafe.Pointer(&failthreadcreate[0]), int32(len(failthreadcreate)))
-		exit(1)
-	}
-
-	// The caller passes in a suggested stack size,
-	// from when we allocated the stack and thread ourselves,
-	// without libpthread. Now that we're using libpthread,
-	// we use the OS default stack size instead of the suggestion.
-	// Find out that stack size for our own stack guard.
-	if pthread_attr_getstacksize(&attr, &stacksize) != 0 {
-		write(2, unsafe.Pointer(&failthreadcreate[0]), int32(len(failthreadcreate)))
-		exit(1)
-	}
-	g0.stack.hi = stacksize // for mstart
-	memstats.stacks_sys.add(int64(stacksize))
-
-	// Tell the pthread library we won't join with this thread.
-	if pthread_attr_setdetachstate(&attr, _PTHREAD_CREATE_DETACHED) != 0 {
-		write(2, unsafe.Pointer(&failthreadcreate[0]), int32(len(failthreadcreate)))
-		exit(1)
-	}
-
-	// Finally, create the thread. It starts at mstart_stub, which does some low-level
-	// setup and then calls mstart.
-	var oset sigset
-	sigprocmask(_SIG_SETMASK, &sigset_all, &oset)
-	err = pthread_create(&attr, fn, nil)
-	sigprocmask(_SIG_SETMASK, &oset, nil)
-	if err != 0 {
-		write(2, unsafe.Pointer(&failthreadcreate[0]), int32(len(failthreadcreate)))
-		exit(1)
-	}
-}
-
-var failallocatestack = []byte("runtime: failed to allocate stack for the new OS thread\n")
-var failthreadcreate = []byte("runtime: failed to create new OS thread\n")
-
-// Called to do synchronous initialization of Go code built with
-// -buildmode=c-archive or -buildmode=c-shared.
-// None of the Go runtime is initialized.
-//go:nosplit
-//go:nowritebarrierrec
-func libpreinit() {
-	initsig(true)
-}
-
-// Called to initialize a new m (including the bootstrap m).
-// Called on the parent thread (main thread in case of bootstrap), can allocate memory.
-func mpreinit(mp *m) {
-	mp.gsignal = malg(32 * 1024) // OS X wants >= 8K
-	mp.gsignal.m = mp
-	if GOOS == "darwin" && GOARCH == "arm64" {
-		// mlock the signal stack to work around a kernel bug where it may
-		// SIGILL when the signal stack is not faulted in while a signal
-		// arrives. See issue 42774.
-		mlock(unsafe.Pointer(mp.gsignal.stack.hi-physPageSize), physPageSize)
-	}
-}
-
-// Called to initialize a new m (including the bootstrap m).
-// Called on the new thread, cannot allocate memory.
-func minit() {
-	// iOS does not support alternate signal stack.
-	// The signal handler handles it directly.
-	if !(GOOS == "ios" && GOARCH == "arm64") {
-		minitSignalStack()
-	}
-	minitSignalMask()
-	getg().m.procid = uint64(pthread_self())
-}
-
-// Called from dropm to undo the effect of an minit.
-//go:nosplit
-func unminit() {
-	// iOS does not support alternate signal stack.
-	// See minit.
-	if !(GOOS == "ios" && GOARCH == "arm64") {
-		unminitSignals()
-	}
-}
-
-// Called from exitm, but not from drop, to undo the effect of thread-owned
-// resources in minit, semacreate, or elsewhere. Do not take locks after calling this.
-func mdestroy(mp *m) {
-}
-
-//go:nosplit
-func osyield_no_g() {
-	usleep_no_g(1)
-}
-
-//go:nosplit
-func osyield() {
-	usleep(1)
-}
-
-const (
-	_NSIG        = 32
-	_SI_USER     = 0 /* empirically true, but not what headers say */
-	_SIG_BLOCK   = 1
-	_SIG_UNBLOCK = 2
-	_SIG_SETMASK = 3
-	_SS_DISABLE  = 4
-)
-
-//extern SigTabTT runtime·sigtab[];
-
-type sigset uint32
-
-var sigset_all = ^sigset(0)
-
-//go:nosplit
-//go:nowritebarrierrec
-func setsig(i uint32, fn uintptr) {
-	var sa usigactiont
-	sa.sa_flags = _SA_SIGINFO | _SA_ONSTACK | _SA_RESTART
-	sa.sa_mask = ^uint32(0)
-	if fn == abi.FuncPCABIInternal(sighandler) { // abi.FuncPCABIInternal(sighandler) matches the callers in signal_unix.go
-		if iscgo {
-			fn = abi.FuncPCABI0(cgoSigtramp)
-		} else {
-			fn = abi.FuncPCABI0(sigtramp)
-		}
-	}
-	*(*uintptr)(unsafe.Pointer(&sa.__sigaction_u)) = fn
-	sigaction(i, &sa, nil)
-}
-
-// sigtramp is the callback from libc when a signal is received.
-// It is called with the C calling convention.
-func sigtramp()
-func cgoSigtramp()
-
-//go:nosplit
-//go:nowritebarrierrec
-func setsigstack(i uint32) {
-	var osa usigactiont
-	sigaction(i, nil, &osa)
-	handler := *(*uintptr)(unsafe.Pointer(&osa.__sigaction_u))
-	if osa.sa_flags&_SA_ONSTACK != 0 {
-		return
-	}
-	var sa usigactiont
-	*(*uintptr)(unsafe.Pointer(&sa.__sigaction_u)) = handler
-	sa.sa_mask = osa.sa_mask
-	sa.sa_flags = osa.sa_flags | _SA_ONSTACK
-	sigaction(i, &sa, nil)
-}
-
-//go:nosplit
-//go:nowritebarrierrec
-func getsig(i uint32) uintptr {
-	var sa usigactiont
-	sigaction(i, nil, &sa)
-	return *(*uintptr)(unsafe.Pointer(&sa.__sigaction_u))
-}
-
-// setSignaltstackSP sets the ss_sp field of a stackt.
-//go:nosplit
-func setSignalstackSP(s *stackt, sp uintptr) {
-	*(*uintptr)(unsafe.Pointer(&s.ss_sp)) = sp
-}
-
-//go:nosplit
-//go:nowritebarrierrec
-func sigaddset(mask *sigset, i int) {
-	*mask |= 1 << (uint32(i) - 1)
-}
-
-func sigdelset(mask *sigset, i int) {
-	*mask &^= 1 << (uint32(i) - 1)
-}
-
-func setProcessCPUProfiler(hz int32) {
-	setProcessCPUProfilerTimer(hz)
-}
-
-func setThreadCPUProfiler(hz int32) {
-	setThreadCPUProfilerHz(hz)
-}
-
-//go:nosplit
-func validSIGPROF(mp *m, c *sigctxt) bool {
-	return true
-}
-
-//go:linkname executablePath os.executablePath
-var executablePath string
-
-func sysargs(argc int32, argv **byte) {
-	// skip over argv, envv and the first string will be the path
-	n := argc + 1
-	for argv_index(argv, n) != nil {
-		n++
-	}
-	executablePath = gostringnocopy(argv_index(argv, n+1))
-
-	// strip "executable_path=" prefix if available, it's added after OS X 10.11.
-	const prefix = "executable_path="
-	if len(executablePath) > len(prefix) && executablePath[:len(prefix)] == prefix {
-		executablePath = executablePath[len(prefix):]
-	}
-}
-
-func signalM(mp *m, sig int) {
-	pthread_kill(pthread(mp.procid), uint32(sig))
-}
-
-// sigPerThreadSyscall is only used on linux, so we assign a bogus signal
-// number.
-const sigPerThreadSyscall = 1 << 31
-
-//go:nosplit
-func runPerThreadSyscall() {
-	throw("runPerThreadSyscall only valid on linux")
-}
diff --git a/contrib/go/_std_1.18/src/runtime/os_linux.go b/contrib/go/_std_1.18/src/runtime/os_linux.go
deleted file mode 100644
index eb8aa076e9..0000000000
--- a/contrib/go/_std_1.18/src/runtime/os_linux.go
+++ /dev/null
@@ -1,878 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"internal/abi"
-	"internal/goarch"
-	"runtime/internal/atomic"
-	"runtime/internal/syscall"
-	"unsafe"
-)
-
-// sigPerThreadSyscall is the same signal (SIGSETXID) used by glibc for
-// per-thread syscalls on Linux. We use it for the same purpose in non-cgo
-// binaries.
-const sigPerThreadSyscall = _SIGRTMIN + 1
-
-type mOS struct {
-	// profileTimer holds the ID of the POSIX interval timer for profiling CPU
-	// usage on this thread.
-	//
-	// It is valid when the profileTimerValid field is non-zero. A thread
-	// creates and manages its own timer, and these fields are read and written
-	// only by this thread. But because some of the reads on profileTimerValid
-	// are in signal handling code, access to that field uses atomic operations.
-	profileTimer      int32
-	profileTimerValid uint32
-
-	// needPerThreadSyscall indicates that a per-thread syscall is required
-	// for doAllThreadsSyscall.
-	needPerThreadSyscall atomic.Uint8
-}
-
-//go:noescape
-func futex(addr unsafe.Pointer, op int32, val uint32, ts, addr2 unsafe.Pointer, val3 uint32) int32
-
-// Linux futex.
-//
-//	futexsleep(uint32 *addr, uint32 val)
-//	futexwakeup(uint32 *addr)
-//
-// Futexsleep atomically checks if *addr == val and if so, sleeps on addr.
-// Futexwakeup wakes up threads sleeping on addr.
-// Futexsleep is allowed to wake up spuriously.
-
-const (
-	_FUTEX_PRIVATE_FLAG = 128
-	_FUTEX_WAIT_PRIVATE = 0 | _FUTEX_PRIVATE_FLAG
-	_FUTEX_WAKE_PRIVATE = 1 | _FUTEX_PRIVATE_FLAG
-)
-
-// Atomically,
-//	if(*addr == val) sleep
-// Might be woken up spuriously; that's allowed.
-// Don't sleep longer than ns; ns < 0 means forever.
-//go:nosplit
-func futexsleep(addr *uint32, val uint32, ns int64) {
-	// Some Linux kernels have a bug where futex of
-	// FUTEX_WAIT returns an internal error code
-	// as an errno. Libpthread ignores the return value
-	// here, and so can we: as it says a few lines up,
-	// spurious wakeups are allowed.
-	if ns < 0 {
-		futex(unsafe.Pointer(addr), _FUTEX_WAIT_PRIVATE, val, nil, nil, 0)
-		return
-	}
-
-	var ts timespec
-	ts.setNsec(ns)
-	futex(unsafe.Pointer(addr), _FUTEX_WAIT_PRIVATE, val, unsafe.Pointer(&ts), nil, 0)
-}
-
-// If any procs are sleeping on addr, wake up at most cnt.
-//go:nosplit
-func futexwakeup(addr *uint32, cnt uint32) {
-	ret := futex(unsafe.Pointer(addr), _FUTEX_WAKE_PRIVATE, cnt, nil, nil, 0)
-	if ret >= 0 {
-		return
-	}
-
-	// I don't know that futex wakeup can return
-	// EAGAIN or EINTR, but if it does, it would be
-	// safe to loop and call futex again.
-	systemstack(func() {
-		print("futexwakeup addr=", addr, " returned ", ret, "\n")
-	})
-
-	*(*int32)(unsafe.Pointer(uintptr(0x1006))) = 0x1006
-}
-
-func getproccount() int32 {
-	// This buffer is huge (8 kB) but we are on the system stack
-	// and there should be plenty of space (64 kB).
-	// Also this is a leaf, so we're not holding up the memory for long.
-	// See golang.org/issue/11823.
-	// The suggested behavior here is to keep trying with ever-larger
-	// buffers, but we don't have a dynamic memory allocator at the
-	// moment, so that's a bit tricky and seems like overkill.
-	const maxCPUs = 64 * 1024
-	var buf [maxCPUs / 8]byte
-	r := sched_getaffinity(0, unsafe.Sizeof(buf), &buf[0])
-	if r < 0 {
-		return 1
-	}
-	n := int32(0)
-	for _, v := range buf[:r] {
-		for v != 0 {
-			n += int32(v & 1)
-			v >>= 1
-		}
-	}
-	if n == 0 {
-		n = 1
-	}
-	return n
-}
-
-// Clone, the Linux rfork.
-const (
-	_CLONE_VM             = 0x100
-	_CLONE_FS             = 0x200
-	_CLONE_FILES          = 0x400
-	_CLONE_SIGHAND        = 0x800
-	_CLONE_PTRACE         = 0x2000
-	_CLONE_VFORK          = 0x4000
-	_CLONE_PARENT         = 0x8000
-	_CLONE_THREAD         = 0x10000
-	_CLONE_NEWNS          = 0x20000
-	_CLONE_SYSVSEM        = 0x40000
-	_CLONE_SETTLS         = 0x80000
-	_CLONE_PARENT_SETTID  = 0x100000
-	_CLONE_CHILD_CLEARTID = 0x200000
-	_CLONE_UNTRACED       = 0x800000
-	_CLONE_CHILD_SETTID   = 0x1000000
-	_CLONE_STOPPED        = 0x2000000
-	_CLONE_NEWUTS         = 0x4000000
-	_CLONE_NEWIPC         = 0x8000000
-
-	// As of QEMU 2.8.0 (5ea2fc84d), user emulation requires all six of these
-	// flags to be set when creating a thread; attempts to share the other
-	// five but leave SYSVSEM unshared will fail with -EINVAL.
-	//
-	// In non-QEMU environments CLONE_SYSVSEM is inconsequential as we do not
-	// use System V semaphores.
-
-	cloneFlags = _CLONE_VM | /* share memory */
-		_CLONE_FS | /* share cwd, etc */
-		_CLONE_FILES | /* share fd table */
-		_CLONE_SIGHAND | /* share sig handler table */
-		_CLONE_SYSVSEM | /* share SysV semaphore undo lists (see issue #20763) */
-		_CLONE_THREAD /* revisit - okay for now */
-)
-
-//go:noescape
-func clone(flags int32, stk, mp, gp, fn unsafe.Pointer) int32
-
-// May run with m.p==nil, so write barriers are not allowed.
-//go:nowritebarrier
-func newosproc(mp *m) {
-	stk := unsafe.Pointer(mp.g0.stack.hi)
-	/*
-	 * note: strace gets confused if we use CLONE_PTRACE here.
-	 */
-	if false {
-		print("newosproc stk=", stk, " m=", mp, " g=", mp.g0, " clone=", abi.FuncPCABI0(clone), " id=", mp.id, " ostk=", &mp, "\n")
-	}
-
-	// Disable signals during clone, so that the new thread starts
-	// with signals disabled. It will enable them in minit.
-	var oset sigset
-	sigprocmask(_SIG_SETMASK, &sigset_all, &oset)
-	ret := clone(cloneFlags, stk, unsafe.Pointer(mp), unsafe.Pointer(mp.g0), unsafe.Pointer(abi.FuncPCABI0(mstart)))
-	sigprocmask(_SIG_SETMASK, &oset, nil)
-
-	if ret < 0 {
-		print("runtime: failed to create new OS thread (have ", mcount(), " already; errno=", -ret, ")\n")
-		if ret == -_EAGAIN {
-			println("runtime: may need to increase max user processes (ulimit -u)")
-		}
-		throw("newosproc")
-	}
-}
-
-// Version of newosproc that doesn't require a valid G.
-//go:nosplit
-func newosproc0(stacksize uintptr, fn unsafe.Pointer) {
-	stack := sysAlloc(stacksize, &memstats.stacks_sys)
-	if stack == nil {
-		write(2, unsafe.Pointer(&failallocatestack[0]), int32(len(failallocatestack)))
-		exit(1)
-	}
-	ret := clone(cloneFlags, unsafe.Pointer(uintptr(stack)+stacksize), nil, nil, fn)
-	if ret < 0 {
-		write(2, unsafe.Pointer(&failthreadcreate[0]), int32(len(failthreadcreate)))
-		exit(1)
-	}
-}
-
-var failallocatestack = []byte("runtime: failed to allocate stack for the new OS thread\n")
-var failthreadcreate = []byte("runtime: failed to create new OS thread\n")
-
-const (
-	_AT_NULL   = 0  // End of vector
-	_AT_PAGESZ = 6  // System physical page size
-	_AT_HWCAP  = 16 // hardware capability bit vector
-	_AT_RANDOM = 25 // introduced in 2.6.29
-	_AT_HWCAP2 = 26 // hardware capability bit vector 2
-)
-
-var procAuxv = []byte("/proc/self/auxv\x00")
-
-var addrspace_vec [1]byte
-
-func mincore(addr unsafe.Pointer, n uintptr, dst *byte) int32
-
-func sysargs(argc int32, argv **byte) {
-	n := argc + 1
-
-	// skip over argv, envp to get to auxv
-	for argv_index(argv, n) != nil {
-		n++
-	}
-
-	// skip NULL separator
-	n++
-
-	// now argv+n is auxv
-	auxv := (*[1 << 28]uintptr)(add(unsafe.Pointer(argv), uintptr(n)*goarch.PtrSize))
-	if sysauxv(auxv[:]) != 0 {
-		return
-	}
-	// In some situations we don't get a loader-provided
-	// auxv, such as when loaded as a library on Android.
-	// Fall back to /proc/self/auxv.
-	fd := open(&procAuxv[0], 0 /* O_RDONLY */, 0)
-	if fd < 0 {
-		// On Android, /proc/self/auxv might be unreadable (issue 9229), so we fallback to
-		// try using mincore to detect the physical page size.
-		// mincore should return EINVAL when address is not a multiple of system page size.
-		const size = 256 << 10 // size of memory region to allocate
-		p, err := mmap(nil, size, _PROT_READ|_PROT_WRITE, _MAP_ANON|_MAP_PRIVATE, -1, 0)
-		if err != 0 {
-			return
-		}
-		var n uintptr
-		for n = 4 << 10; n < size; n <<= 1 {
-			err := mincore(unsafe.Pointer(uintptr(p)+n), 1, &addrspace_vec[0])
-			if err == 0 {
-				physPageSize = n
-				break
-			}
-		}
-		if physPageSize == 0 {
-			physPageSize = size
-		}
-		munmap(p, size)
-		return
-	}
-	var buf [128]uintptr
-	n = read(fd, noescape(unsafe.Pointer(&buf[0])), int32(unsafe.Sizeof(buf)))
-	closefd(fd)
-	if n < 0 {
-		return
-	}
-	// Make sure buf is terminated, even if we didn't read
-	// the whole file.
-	buf[len(buf)-2] = _AT_NULL
-	sysauxv(buf[:])
-}
-
-// startupRandomData holds random bytes initialized at startup. These come from
-// the ELF AT_RANDOM auxiliary vector.
-var startupRandomData []byte
-
-func sysauxv(auxv []uintptr) int {
-	var i int
-	for ; auxv[i] != _AT_NULL; i += 2 {
-		tag, val := auxv[i], auxv[i+1]
-		switch tag {
-		case _AT_RANDOM:
-			// The kernel provides a pointer to 16-bytes
-			// worth of random data.
-			startupRandomData = (*[16]byte)(unsafe.Pointer(val))[:]
-
-		case _AT_PAGESZ:
-			physPageSize = val
-		}
-
-		archauxv(tag, val)
-		vdsoauxv(tag, val)
-	}
-	return i / 2
-}
-
-var sysTHPSizePath = []byte("/sys/kernel/mm/transparent_hugepage/hpage_pmd_size\x00")
-
-func getHugePageSize() uintptr {
-	var numbuf [20]byte
-	fd := open(&sysTHPSizePath[0], 0 /* O_RDONLY */, 0)
-	if fd < 0 {
-		return 0
-	}
-	ptr := noescape(unsafe.Pointer(&numbuf[0]))
-	n := read(fd, ptr, int32(len(numbuf)))
-	closefd(fd)
-	if n <= 0 {
-		return 0
-	}
-	n-- // remove trailing newline
-	v, ok := atoi(slicebytetostringtmp((*byte)(ptr), int(n)))
-	if !ok || v < 0 {
-		v = 0
-	}
-	if v&(v-1) != 0 {
-		// v is not a power of 2
-		return 0
-	}
-	return uintptr(v)
-}
-
-func osinit() {
-	ncpu = getproccount()
-	physHugePageSize = getHugePageSize()
-	if iscgo {
-		// #42494 glibc and musl reserve some signals for
-		// internal use and require they not be blocked by
-		// the rest of a normal C runtime. When the go runtime
-		// blocks...unblocks signals, temporarily, the blocked
-		// interval of time is generally very short. As such,
-		// these expectations of *libc code are mostly met by
-		// the combined go+cgo system of threads. However,
-		// when go causes a thread to exit, via a return from
-		// mstart(), the combined runtime can deadlock if
-		// these signals are blocked. Thus, don't block these
-		// signals when exiting threads.
-		// - glibc: SIGCANCEL (32), SIGSETXID (33)
-		// - musl: SIGTIMER (32), SIGCANCEL (33), SIGSYNCCALL (34)
-		sigdelset(&sigsetAllExiting, 32)
-		sigdelset(&sigsetAllExiting, 33)
-		sigdelset(&sigsetAllExiting, 34)
-	}
-	osArchInit()
-}
-
-var urandom_dev = []byte("/dev/urandom\x00")
-
-func getRandomData(r []byte) {
-	if startupRandomData != nil {
-		n := copy(r, startupRandomData)
-		extendRandom(r, n)
-		return
-	}
-	fd := open(&urandom_dev[0], 0 /* O_RDONLY */, 0)
-	n := read(fd, unsafe.Pointer(&r[0]), int32(len(r)))
-	closefd(fd)
-	extendRandom(r, int(n))
-}
-
-func goenvs() {
-	goenvs_unix()
-}
-
-// Called to do synchronous initialization of Go code built with
-// -buildmode=c-archive or -buildmode=c-shared.
-// None of the Go runtime is initialized.
-//go:nosplit
-//go:nowritebarrierrec
-func libpreinit() {
-	initsig(true)
-}
-
-// Called to initialize a new m (including the bootstrap m).
-// Called on the parent thread (main thread in case of bootstrap), can allocate memory.
-func mpreinit(mp *m) {
-	mp.gsignal = malg(32 * 1024) // Linux wants >= 2K
-	mp.gsignal.m = mp
-}
-
-func gettid() uint32
-
-// Called to initialize a new m (including the bootstrap m).
-// Called on the new thread, cannot allocate memory.
-func minit() {
-	minitSignals()
-
-	// Cgo-created threads and the bootstrap m are missing a
-	// procid. We need this for asynchronous preemption and it's
-	// useful in debuggers.
-	getg().m.procid = uint64(gettid())
-}
-
-// Called from dropm to undo the effect of an minit.
-//go:nosplit
-func unminit() {
-	unminitSignals()
-}
-
-// Called from exitm, but not from drop, to undo the effect of thread-owned
-// resources in minit, semacreate, or elsewhere. Do not take locks after calling this.
-func mdestroy(mp *m) {
-}
-
-//#ifdef GOARCH_386
-//#define sa_handler k_sa_handler
-//#endif
-
-func sigreturn()
-func sigtramp() // Called via C ABI
-func cgoSigtramp()
-
-//go:noescape
-func sigaltstack(new, old *stackt)
-
-//go:noescape
-func setitimer(mode int32, new, old *itimerval)
-
-//go:noescape
-func timer_create(clockid int32, sevp *sigevent, timerid *int32) int32
-
-//go:noescape
-func timer_settime(timerid int32, flags int32, new, old *itimerspec) int32
-
-//go:noescape
-func timer_delete(timerid int32) int32
-
-//go:noescape
-func rtsigprocmask(how int32, new, old *sigset, size int32)
-
-//go:nosplit
-//go:nowritebarrierrec
-func sigprocmask(how int32, new, old *sigset) {
-	rtsigprocmask(how, new, old, int32(unsafe.Sizeof(*new)))
-}
-
-func raise(sig uint32)
-func raiseproc(sig uint32)
-
-//go:noescape
-func sched_getaffinity(pid, len uintptr, buf *byte) int32
-func osyield()
-
-//go:nosplit
-func osyield_no_g() {
-	osyield()
-}
-
-func pipe() (r, w int32, errno int32)
-func pipe2(flags int32) (r, w int32, errno int32)
-func setNonblock(fd int32)
-
-const (
-	_si_max_size    = 128
-	_sigev_max_size = 64
-)
-
-//go:nosplit
-//go:nowritebarrierrec
-func setsig(i uint32, fn uintptr) {
-	var sa sigactiont
-	sa.sa_flags = _SA_SIGINFO | _SA_ONSTACK | _SA_RESTORER | _SA_RESTART
-	sigfillset(&sa.sa_mask)
-	// Although Linux manpage says "sa_restorer element is obsolete and
-	// should not be used". x86_64 kernel requires it. Only use it on
-	// x86.
-	if GOARCH == "386" || GOARCH == "amd64" {
-		sa.sa_restorer = abi.FuncPCABI0(sigreturn)
-	}
-	if fn == abi.FuncPCABIInternal(sighandler) { // abi.FuncPCABIInternal(sighandler) matches the callers in signal_unix.go
-		if iscgo {
-			fn = abi.FuncPCABI0(cgoSigtramp)
-		} else {
-			fn = abi.FuncPCABI0(sigtramp)
-		}
-	}
-	sa.sa_handler = fn
-	sigaction(i, &sa, nil)
-}
-
-//go:nosplit
-//go:nowritebarrierrec
-func setsigstack(i uint32) {
-	var sa sigactiont
-	sigaction(i, nil, &sa)
-	if sa.sa_flags&_SA_ONSTACK != 0 {
-		return
-	}
-	sa.sa_flags |= _SA_ONSTACK
-	sigaction(i, &sa, nil)
-}
-
-//go:nosplit
-//go:nowritebarrierrec
-func getsig(i uint32) uintptr {
-	var sa sigactiont
-	sigaction(i, nil, &sa)
-	return sa.sa_handler
-}
-
-// setSignaltstackSP sets the ss_sp field of a stackt.
-//go:nosplit
-func setSignalstackSP(s *stackt, sp uintptr) {
-	*(*uintptr)(unsafe.Pointer(&s.ss_sp)) = sp
-}
-
-//go:nosplit
-func (c *sigctxt) fixsigcode(sig uint32) {
-}
-
-// sysSigaction calls the rt_sigaction system call.
-//go:nosplit
-func sysSigaction(sig uint32, new, old *sigactiont) {
-	if rt_sigaction(uintptr(sig), new, old, unsafe.Sizeof(sigactiont{}.sa_mask)) != 0 {
-		// Workaround for bugs in QEMU user mode emulation.
-		//
-		// QEMU turns calls to the sigaction system call into
-		// calls to the C library sigaction call; the C
-		// library call rejects attempts to call sigaction for
-		// SIGCANCEL (32) or SIGSETXID (33).
-		//
-		// QEMU rejects calling sigaction on SIGRTMAX (64).
-		//
-		// Just ignore the error in these case. There isn't
-		// anything we can do about it anyhow.
-		if sig != 32 && sig != 33 && sig != 64 {
-			// Use system stack to avoid split stack overflow on ppc64/ppc64le.
-			systemstack(func() {
-				throw("sigaction failed")
-			})
-		}
-	}
-}
-
-// rt_sigaction is implemented in assembly.
-//go:noescape
-func rt_sigaction(sig uintptr, new, old *sigactiont, size uintptr) int32
-
-func getpid() int
-func tgkill(tgid, tid, sig int)
-
-// signalM sends a signal to mp.
-func signalM(mp *m, sig int) {
-	tgkill(getpid(), int(mp.procid), sig)
-}
-
-// go118UseTimerCreateProfiler enables the per-thread CPU profiler.
-const go118UseTimerCreateProfiler = true
-
-// validSIGPROF compares this signal delivery's code against the signal sources
-// that the profiler uses, returning whether the delivery should be processed.
-// To be processed, a signal delivery from a known profiling mechanism should
-// correspond to the best profiling mechanism available to this thread. Signals
-// from other sources are always considered valid.
-//
-//go:nosplit
-func validSIGPROF(mp *m, c *sigctxt) bool {
-	code := int32(c.sigcode())
-	setitimer := code == _SI_KERNEL
-	timer_create := code == _SI_TIMER
-
-	if !(setitimer || timer_create) {
-		// The signal doesn't correspond to a profiling mechanism that the
-		// runtime enables itself. There's no reason to process it, but there's
-		// no reason to ignore it either.
-		return true
-	}
-
-	if mp == nil {
-		// Since we don't have an M, we can't check if there's an active
-		// per-thread timer for this thread. We don't know how long this thread
-		// has been around, and if it happened to interact with the Go scheduler
-		// at a time when profiling was active (causing it to have a per-thread
-		// timer). But it may have never interacted with the Go scheduler, or
-		// never while profiling was active. To avoid double-counting, process
-		// only signals from setitimer.
-		//
-		// When a custom cgo traceback function has been registered (on
-		// platforms that support runtime.SetCgoTraceback), SIGPROF signals
-		// delivered to a thread that cannot find a matching M do this check in
-		// the assembly implementations of runtime.cgoSigtramp.
-		return setitimer
-	}
-
-	// Having an M means the thread interacts with the Go scheduler, and we can
-	// check whether there's an active per-thread timer for this thread.
-	if atomic.Load(&mp.profileTimerValid) != 0 {
-		// If this M has its own per-thread CPU profiling interval timer, we
-		// should track the SIGPROF signals that come from that timer (for
-		// accurate reporting of its CPU usage; see issue 35057) and ignore any
-		// that it gets from the process-wide setitimer (to not over-count its
-		// CPU consumption).
-		return timer_create
-	}
-
-	// No active per-thread timer means the only valid profiler is setitimer.
-	return setitimer
-}
-
-func setProcessCPUProfiler(hz int32) {
-	setProcessCPUProfilerTimer(hz)
-}
-
-func setThreadCPUProfiler(hz int32) {
-	mp := getg().m
-	mp.profilehz = hz
-
-	if !go118UseTimerCreateProfiler {
-		return
-	}
-
-	// destroy any active timer
-	if atomic.Load(&mp.profileTimerValid) != 0 {
-		timerid := mp.profileTimer
-		atomic.Store(&mp.profileTimerValid, 0)
-		mp.profileTimer = 0
-
-		ret := timer_delete(timerid)
-		if ret != 0 {
-			print("runtime: failed to disable profiling timer; timer_delete(", timerid, ") errno=", -ret, "\n")
-			throw("timer_delete")
-		}
-	}
-
-	if hz == 0 {
-		// If the goal was to disable profiling for this thread, then the job's done.
-		return
-	}
-
-	// The period of the timer should be 1/Hz. For every "1/Hz" of additional
-	// work, the user should expect one additional sample in the profile.
-	//
-	// But to scale down to very small amounts of application work, to observe
-	// even CPU usage of "one tenth" of the requested period, set the initial
-	// timing delay in a different way: So that "one tenth" of a period of CPU
-	// spend shows up as a 10% chance of one sample (for an expected value of
-	// 0.1 samples), and so that "two and six tenths" periods of CPU spend show
-	// up as a 60% chance of 3 samples and a 40% chance of 2 samples (for an
-	// expected value of 2.6). Set the initial delay to a value in the unifom
-	// random distribution between 0 and the desired period. And because "0"
-	// means "disable timer", add 1 so the half-open interval [0,period) turns
-	// into (0,period].
-	//
-	// Otherwise, this would show up as a bias away from short-lived threads and
-	// from threads that are only occasionally active: for example, when the
-	// garbage collector runs on a mostly-idle system, the additional threads it
-	// activates may do a couple milliseconds of GC-related work and nothing
-	// else in the few seconds that the profiler observes.
-	spec := new(itimerspec)
-	spec.it_value.setNsec(1 + int64(fastrandn(uint32(1e9/hz))))
-	spec.it_interval.setNsec(1e9 / int64(hz))
-
-	var timerid int32
-	var sevp sigevent
-	sevp.notify = _SIGEV_THREAD_ID
-	sevp.signo = _SIGPROF
-	sevp.sigev_notify_thread_id = int32(mp.procid)
-	ret := timer_create(_CLOCK_THREAD_CPUTIME_ID, &sevp, &timerid)
-	if ret != 0 {
-		// If we cannot create a timer for this M, leave profileTimerValid false
-		// to fall back to the process-wide setitimer profiler.
-		return
-	}
-
-	ret = timer_settime(timerid, 0, spec, nil)
-	if ret != 0 {
-		print("runtime: failed to configure profiling timer; timer_settime(", timerid,
-			", 0, {interval: {",
-			spec.it_interval.tv_sec, "s + ", spec.it_interval.tv_nsec, "ns} value: {",
-			spec.it_value.tv_sec, "s + ", spec.it_value.tv_nsec, "ns}}, nil) errno=", -ret, "\n")
-		throw("timer_settime")
-	}
-
-	mp.profileTimer = timerid
-	atomic.Store(&mp.profileTimerValid, 1)
-}
-
-// perThreadSyscallArgs contains the system call number, arguments, and
-// expected return values for a system call to be executed on all threads.
-type perThreadSyscallArgs struct {
-	trap uintptr
-	a1   uintptr
-	a2   uintptr
-	a3   uintptr
-	a4   uintptr
-	a5   uintptr
-	a6   uintptr
-	r1   uintptr
-	r2   uintptr
-}
-
-// perThreadSyscall is the system call to execute for the ongoing
-// doAllThreadsSyscall.
-//
-// perThreadSyscall may only be written while mp.needPerThreadSyscall == 0 on
-// all Ms.
-var perThreadSyscall perThreadSyscallArgs
-
-// syscall_runtime_doAllThreadsSyscall and executes a specified system call on
-// all Ms.
-//
-// The system call is expected to succeed and return the same value on every
-// thread. If any threads do not match, the runtime throws.
-//
-//go:linkname syscall_runtime_doAllThreadsSyscall syscall.runtime_doAllThreadsSyscall
-//go:uintptrescapes
-func syscall_runtime_doAllThreadsSyscall(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr) {
-	if iscgo {
-		// In cgo, we are not aware of threads created in C, so this approach will not work.
-		panic("doAllThreadsSyscall not supported with cgo enabled")
-	}
-
-	// STW to guarantee that user goroutines see an atomic change to thread
-	// state. Without STW, goroutines could migrate Ms while change is in
-	// progress and e.g., see state old -> new -> old -> new.
-	//
-	// N.B. Internally, this function does not depend on STW to
-	// successfully change every thread. It is only needed for user
-	// expectations, per above.
-	stopTheWorld("doAllThreadsSyscall")
-
-	// This function depends on several properties:
-	//
-	// 1. All OS threads that already exist are associated with an M in
-	//    allm. i.e., we won't miss any pre-existing threads.
-	// 2. All Ms listed in allm will eventually have an OS thread exist.
-	//    i.e., they will set procid and be able to receive signals.
-	// 3. OS threads created after we read allm will clone from a thread
-	//    that has executed the system call. i.e., they inherit the
-	//    modified state.
-	//
-	// We achieve these through different mechanisms:
-	//
-	// 1. Addition of new Ms to allm in allocm happens before clone of its
-	//    OS thread later in newm.
-	// 2. newm does acquirem to avoid being preempted, ensuring that new Ms
-	//    created in allocm will eventually reach OS thread clone later in
-	//    newm.
-	// 3. We take allocmLock for write here to prevent allocation of new Ms
-	//    while this function runs. Per (1), this prevents clone of OS
-	//    threads that are not yet in allm.
-	allocmLock.lock()
-
-	// Disable preemption, preventing us from changing Ms, as we handle
-	// this M specially.
-	//
-	// N.B. STW and lock() above do this as well, this is added for extra
-	// clarity.
-	acquirem()
-
-	// N.B. allocmLock also prevents concurrent execution of this function,
-	// serializing use of perThreadSyscall, mp.needPerThreadSyscall, and
-	// ensuring all threads execute system calls from multiple calls in the
-	// same order.
-
-	r1, r2, errno := syscall.Syscall6(trap, a1, a2, a3, a4, a5, a6)
-	if GOARCH == "ppc64" || GOARCH == "ppc64le" {
-		// TODO(https://go.dev/issue/51192 ): ppc64 doesn't use r2.
-		r2 = 0
-	}
-	if errno != 0 {
-		releasem(getg().m)
-		allocmLock.unlock()
-		startTheWorld()
-		return r1, r2, errno
-	}
-
-	perThreadSyscall = perThreadSyscallArgs{
-		trap: trap,
-		a1:   a1,
-		a2:   a2,
-		a3:   a3,
-		a4:   a4,
-		a5:   a5,
-		a6:   a6,
-		r1:   r1,
-		r2:   r2,
-	}
-
-	// Wait for all threads to start.
-	//
-	// As described above, some Ms have been added to allm prior to
-	// allocmLock, but not yet completed OS clone and set procid.
-	//
-	// At minimum we must wait for a thread to set procid before we can
-	// send it a signal.
-	//
-	// We take this one step further and wait for all threads to start
-	// before sending any signals. This prevents system calls from getting
-	// applied twice: once in the parent and once in the child, like so:
-	//
-	//          A                     B                  C
-	//                         add C to allm
-	// doAllThreadsSyscall
-	//   allocmLock.lock()
-	//   signal B
-	//                         <receive signal>
-	//                         execute syscall
-	//                         <signal return>
-	//                         clone C
-	//                                             <thread start>
-	//                                             set procid
-	//   signal C
-	//                                             <receive signal>
-	//                                             execute syscall
-	//                                             <signal return>
-	//
-	// In this case, thread C inherited the syscall-modified state from
-	// thread B and did not need to execute the syscall, but did anyway
-	// because doAllThreadsSyscall could not be sure whether it was
-	// required.
-	//
-	// Some system calls may not be idempotent, so we ensure each thread
-	// executes the system call exactly once.
-	for mp := allm; mp != nil; mp = mp.alllink {
-		for atomic.Load64(&mp.procid) == 0 {
-			// Thread is starting.
-			osyield()
-		}
-	}
-
-	// Signal every other thread, where they will execute perThreadSyscall
-	// from the signal handler.
-	gp := getg()
-	tid := gp.m.procid
-	for mp := allm; mp != nil; mp = mp.alllink {
-		if atomic.Load64(&mp.procid) == tid {
-			// Our thread already performed the syscall.
-			continue
-		}
-		mp.needPerThreadSyscall.Store(1)
-		signalM(mp, sigPerThreadSyscall)
-	}
-
-	// Wait for all threads to complete.
-	for mp := allm; mp != nil; mp = mp.alllink {
-		if mp.procid == tid {
-			continue
-		}
-		for mp.needPerThreadSyscall.Load() != 0 {
-			osyield()
-		}
-	}
-
-	perThreadSyscall = perThreadSyscallArgs{}
-
-	releasem(getg().m)
-	allocmLock.unlock()
-	startTheWorld()
-
-	return r1, r2, errno
-}
-
-// runPerThreadSyscall runs perThreadSyscall for this M if required.
-//
-// This function throws if the system call returns with anything other than the
-// expected values.
-//go:nosplit
-func runPerThreadSyscall() {
-	gp := getg()
-	if gp.m.needPerThreadSyscall.Load() == 0 {
-		return
-	}
-
-	args := perThreadSyscall
-	r1, r2, errno := syscall.Syscall6(args.trap, args.a1, args.a2, args.a3, args.a4, args.a5, args.a6)
-	if GOARCH == "ppc64" || GOARCH == "ppc64le" {
-		// TODO(https://go.dev/issue/51192 ): ppc64 doesn't use r2.
-		r2 = 0
-	}
-	if errno != 0 || r1 != args.r1 || r2 != args.r2 {
-		print("trap:", args.trap, ", a123456=[", args.a1, ",", args.a2, ",", args.a3, ",", args.a4, ",", args.a5, ",", args.a6, "]\n")
-		print("results: got {r1=", r1, ",r2=", r2, ",errno=", errno, "}, want {r1=", args.r1, ",r2=", args.r2, ",errno=0\n")
-		throw("AllThreadsSyscall6 results differ between threads; runtime corrupted")
-	}
-
-	gp.m.needPerThreadSyscall.Store(0)
-}
diff --git a/contrib/go/_std_1.18/src/runtime/os_linux_noauxv.go b/contrib/go/_std_1.18/src/runtime/os_linux_noauxv.go
deleted file mode 100644
index 7b84f713d6..0000000000
--- a/contrib/go/_std_1.18/src/runtime/os_linux_noauxv.go
+++ /dev/null
@@ -1,10 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build linux && !arm && !arm64 && !mips && !mipsle && !mips64 && !mips64le && !s390x && !ppc64 && !ppc64le
-
-package runtime
-
-func archauxv(tag, val uintptr) {
-}
diff --git a/contrib/go/_std_1.18/src/runtime/panic.go b/contrib/go/_std_1.18/src/runtime/panic.go
deleted file mode 100644
index 6600410cb6..0000000000
--- a/contrib/go/_std_1.18/src/runtime/panic.go
+++ /dev/null
@@ -1,1292 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"internal/goarch"
-	"runtime/internal/atomic"
-	"runtime/internal/sys"
-	"unsafe"
-)
-
-// We have two different ways of doing defers. The older way involves creating a
-// defer record at the time that a defer statement is executing and adding it to a
-// defer chain. This chain is inspected by the deferreturn call at all function
-// exits in order to run the appropriate defer calls. A cheaper way (which we call
-// open-coded defers) is used for functions in which no defer statements occur in
-// loops. In that case, we simply store the defer function/arg information into
-// specific stack slots at the point of each defer statement, as well as setting a
-// bit in a bitmask. At each function exit, we add inline code to directly make
-// the appropriate defer calls based on the bitmask and fn/arg information stored
-// on the stack. During panic/Goexit processing, the appropriate defer calls are
-// made using extra funcdata info that indicates the exact stack slots that
-// contain the bitmask and defer fn/args.
-
-// Check to make sure we can really generate a panic. If the panic
-// was generated from the runtime, or from inside malloc, then convert
-// to a throw of msg.
-// pc should be the program counter of the compiler-generated code that
-// triggered this panic.
-func panicCheck1(pc uintptr, msg string) {
-	if goarch.IsWasm == 0 && hasPrefix(funcname(findfunc(pc)), "runtime.") {
-		// Note: wasm can't tail call, so we can't get the original caller's pc.
-		throw(msg)
-	}
-	// TODO: is this redundant? How could we be in malloc
-	// but not in the runtime? runtime/internal/*, maybe?
-	gp := getg()
-	if gp != nil && gp.m != nil && gp.m.mallocing != 0 {
-		throw(msg)
-	}
-}
-
-// Same as above, but calling from the runtime is allowed.
-//
-// Using this function is necessary for any panic that may be
-// generated by runtime.sigpanic, since those are always called by the
-// runtime.
-func panicCheck2(err string) {
-	// panic allocates, so to avoid recursive malloc, turn panics
-	// during malloc into throws.
-	gp := getg()
-	if gp != nil && gp.m != nil && gp.m.mallocing != 0 {
-		throw(err)
-	}
-}
-
-// Many of the following panic entry-points turn into throws when they
-// happen in various runtime contexts. These should never happen in
-// the runtime, and if they do, they indicate a serious issue and
-// should not be caught by user code.
-//
-// The panic{Index,Slice,divide,shift} functions are called by
-// code generated by the compiler for out of bounds index expressions,
-// out of bounds slice expressions, division by zero, and shift by negative.
-// The panicdivide (again), panicoverflow, panicfloat, and panicmem
-// functions are called by the signal handler when a signal occurs
-// indicating the respective problem.
-//
-// Since panic{Index,Slice,shift} are never called directly, and
-// since the runtime package should never have an out of bounds slice
-// or array reference or negative shift, if we see those functions called from the
-// runtime package we turn the panic into a throw. That will dump the
-// entire runtime stack for easier debugging.
-//
-// The entry points called by the signal handler will be called from
-// runtime.sigpanic, so we can't disallow calls from the runtime to
-// these (they always look like they're called from the runtime).
-// Hence, for these, we just check for clearly bad runtime conditions.
-//
-// The panic{Index,Slice} functions are implemented in assembly and tail call
-// to the goPanic{Index,Slice} functions below. This is done so we can use
-// a space-minimal register calling convention.
-
-// failures in the comparisons for s[x], 0 <= x < y (y == len(s))
-func goPanicIndex(x int, y int) {
-	panicCheck1(getcallerpc(), "index out of range")
-	panic(boundsError{x: int64(x), signed: true, y: y, code: boundsIndex})
-}
-func goPanicIndexU(x uint, y int) {
-	panicCheck1(getcallerpc(), "index out of range")
-	panic(boundsError{x: int64(x), signed: false, y: y, code: boundsIndex})
-}
-
-// failures in the comparisons for s[:x], 0 <= x <= y (y == len(s) or cap(s))
-func goPanicSliceAlen(x int, y int) {
-	panicCheck1(getcallerpc(), "slice bounds out of range")
-	panic(boundsError{x: int64(x), signed: true, y: y, code: boundsSliceAlen})
-}
-func goPanicSliceAlenU(x uint, y int) {
-	panicCheck1(getcallerpc(), "slice bounds out of range")
-	panic(boundsError{x: int64(x), signed: false, y: y, code: boundsSliceAlen})
-}
-func goPanicSliceAcap(x int, y int) {
-	panicCheck1(getcallerpc(), "slice bounds out of range")
-	panic(boundsError{x: int64(x), signed: true, y: y, code: boundsSliceAcap})
-}
-func goPanicSliceAcapU(x uint, y int) {
-	panicCheck1(getcallerpc(), "slice bounds out of range")
-	panic(boundsError{x: int64(x), signed: false, y: y, code: boundsSliceAcap})
-}
-
-// failures in the comparisons for s[x:y], 0 <= x <= y
-func goPanicSliceB(x int, y int) {
-	panicCheck1(getcallerpc(), "slice bounds out of range")
-	panic(boundsError{x: int64(x), signed: true, y: y, code: boundsSliceB})
-}
-func goPanicSliceBU(x uint, y int) {
-	panicCheck1(getcallerpc(), "slice bounds out of range")
-	panic(boundsError{x: int64(x), signed: false, y: y, code: boundsSliceB})
-}
-
-// failures in the comparisons for s[::x], 0 <= x <= y (y == len(s) or cap(s))
-func goPanicSlice3Alen(x int, y int) {
-	panicCheck1(getcallerpc(), "slice bounds out of range")
-	panic(boundsError{x: int64(x), signed: true, y: y, code: boundsSlice3Alen})
-}
-func goPanicSlice3AlenU(x uint, y int) {
-	panicCheck1(getcallerpc(), "slice bounds out of range")
-	panic(boundsError{x: int64(x), signed: false, y: y, code: boundsSlice3Alen})
-}
-func goPanicSlice3Acap(x int, y int) {
-	panicCheck1(getcallerpc(), "slice bounds out of range")
-	panic(boundsError{x: int64(x), signed: true, y: y, code: boundsSlice3Acap})
-}
-func goPanicSlice3AcapU(x uint, y int) {
-	panicCheck1(getcallerpc(), "slice bounds out of range")
-	panic(boundsError{x: int64(x), signed: false, y: y, code: boundsSlice3Acap})
-}
-
-// failures in the comparisons for s[:x:y], 0 <= x <= y
-func goPanicSlice3B(x int, y int) {
-	panicCheck1(getcallerpc(), "slice bounds out of range")
-	panic(boundsError{x: int64(x), signed: true, y: y, code: boundsSlice3B})
-}
-func goPanicSlice3BU(x uint, y int) {
-	panicCheck1(getcallerpc(), "slice bounds out of range")
-	panic(boundsError{x: int64(x), signed: false, y: y, code: boundsSlice3B})
-}
-
-// failures in the comparisons for s[x:y:], 0 <= x <= y
-func goPanicSlice3C(x int, y int) {
-	panicCheck1(getcallerpc(), "slice bounds out of range")
-	panic(boundsError{x: int64(x), signed: true, y: y, code: boundsSlice3C})
-}
-func goPanicSlice3CU(x uint, y int) {
-	panicCheck1(getcallerpc(), "slice bounds out of range")
-	panic(boundsError{x: int64(x), signed: false, y: y, code: boundsSlice3C})
-}
-
-// failures in the conversion (*[x]T)s, 0 <= x <= y, x == cap(s)
-func goPanicSliceConvert(x int, y int) {
-	panicCheck1(getcallerpc(), "slice length too short to convert to pointer to array")
-	panic(boundsError{x: int64(x), signed: true, y: y, code: boundsConvert})
-}
-
-// Implemented in assembly, as they take arguments in registers.
-// Declared here to mark them as ABIInternal.
-func panicIndex(x int, y int)
-func panicIndexU(x uint, y int)
-func panicSliceAlen(x int, y int)
-func panicSliceAlenU(x uint, y int)
-func panicSliceAcap(x int, y int)
-func panicSliceAcapU(x uint, y int)
-func panicSliceB(x int, y int)
-func panicSliceBU(x uint, y int)
-func panicSlice3Alen(x int, y int)
-func panicSlice3AlenU(x uint, y int)
-func panicSlice3Acap(x int, y int)
-func panicSlice3AcapU(x uint, y int)
-func panicSlice3B(x int, y int)
-func panicSlice3BU(x uint, y int)
-func panicSlice3C(x int, y int)
-func panicSlice3CU(x uint, y int)
-func panicSliceConvert(x int, y int)
-
-var shiftError = error(errorString("negative shift amount"))
-
-func panicshift() {
-	panicCheck1(getcallerpc(), "negative shift amount")
-	panic(shiftError)
-}
-
-var divideError = error(errorString("integer divide by zero"))
-
-func panicdivide() {
-	panicCheck2("integer divide by zero")
-	panic(divideError)
-}
-
-var overflowError = error(errorString("integer overflow"))
-
-func panicoverflow() {
-	panicCheck2("integer overflow")
-	panic(overflowError)
-}
-
-var floatError = error(errorString("floating point error"))
-
-func panicfloat() {
-	panicCheck2("floating point error")
-	panic(floatError)
-}
-
-var memoryError = error(errorString("invalid memory address or nil pointer dereference"))
-
-func panicmem() {
-	panicCheck2("invalid memory address or nil pointer dereference")
-	panic(memoryError)
-}
-
-func panicmemAddr(addr uintptr) {
-	panicCheck2("invalid memory address or nil pointer dereference")
-	panic(errorAddressString{msg: "invalid memory address or nil pointer dereference", addr: addr})
-}
-
-// Create a new deferred function fn, which has no arguments and results.
-// The compiler turns a defer statement into a call to this.
-func deferproc(fn func()) {
-	gp := getg()
-	if gp.m.curg != gp {
-		// go code on the system stack can't defer
-		throw("defer on system stack")
-	}
-
-	d := newdefer()
-	if d._panic != nil {
-		throw("deferproc: d.panic != nil after newdefer")
-	}
-	d.link = gp._defer
-	gp._defer = d
-	d.fn = fn
-	d.pc = getcallerpc()
-	// We must not be preempted between calling getcallersp and
-	// storing it to d.sp because getcallersp's result is a
-	// uintptr stack pointer.
-	d.sp = getcallersp()
-
-	// deferproc returns 0 normally.
-	// a deferred func that stops a panic
-	// makes the deferproc return 1.
-	// the code the compiler generates always
-	// checks the return value and jumps to the
-	// end of the function if deferproc returns != 0.
-	return0()
-	// No code can go here - the C return register has
-	// been set and must not be clobbered.
-}
-
-// deferprocStack queues a new deferred function with a defer record on the stack.
-// The defer record must have its fn field initialized.
-// All other fields can contain junk.
-// Nosplit because of the uninitialized pointer fields on the stack.
-//
-//go:nosplit
-func deferprocStack(d *_defer) {
-	gp := getg()
-	if gp.m.curg != gp {
-		// go code on the system stack can't defer
-		throw("defer on system stack")
-	}
-	// fn is already set.
-	// The other fields are junk on entry to deferprocStack and
-	// are initialized here.
-	d.started = false
-	d.heap = false
-	d.openDefer = false
-	d.sp = getcallersp()
-	d.pc = getcallerpc()
-	d.framepc = 0
-	d.varp = 0
-	// The lines below implement:
-	//   d.panic = nil
-	//   d.fd = nil
-	//   d.link = gp._defer
-	//   gp._defer = d
-	// But without write barriers. The first three are writes to
-	// the stack so they don't need a write barrier, and furthermore
-	// are to uninitialized memory, so they must not use a write barrier.
-	// The fourth write does not require a write barrier because we
-	// explicitly mark all the defer structures, so we don't need to
-	// keep track of pointers to them with a write barrier.
-	*(*uintptr)(unsafe.Pointer(&d._panic)) = 0
-	*(*uintptr)(unsafe.Pointer(&d.fd)) = 0
-	*(*uintptr)(unsafe.Pointer(&d.link)) = uintptr(unsafe.Pointer(gp._defer))
-	*(*uintptr)(unsafe.Pointer(&gp._defer)) = uintptr(unsafe.Pointer(d))
-
-	return0()
-	// No code can go here - the C return register has
-	// been set and must not be clobbered.
-}
-
-// Each P holds a pool for defers.
-
-// Allocate a Defer, usually using per-P pool.
-// Each defer must be released with freedefer.  The defer is not
-// added to any defer chain yet.
-func newdefer() *_defer {
-	var d *_defer
-	mp := acquirem()
-	pp := mp.p.ptr()
-	if len(pp.deferpool) == 0 && sched.deferpool != nil {
-		lock(&sched.deferlock)
-		for len(pp.deferpool) < cap(pp.deferpool)/2 && sched.deferpool != nil {
-			d := sched.deferpool
-			sched.deferpool = d.link
-			d.link = nil
-			pp.deferpool = append(pp.deferpool, d)
-		}
-		unlock(&sched.deferlock)
-	}
-	if n := len(pp.deferpool); n > 0 {
-		d = pp.deferpool[n-1]
-		pp.deferpool[n-1] = nil
-		pp.deferpool = pp.deferpool[:n-1]
-	}
-	releasem(mp)
-	mp, pp = nil, nil
-
-	if d == nil {
-		// Allocate new defer.
-		d = new(_defer)
-	}
-	d.heap = true
-	return d
-}
-
-// Free the given defer.
-// The defer cannot be used after this call.
-//
-// This is nosplit because the incoming defer is in a perilous state.
-// It's not on any defer list, so stack copying won't adjust stack
-// pointers in it (namely, d.link). Hence, if we were to copy the
-// stack, d could then contain a stale pointer.
-//
-//go:nosplit
-func freedefer(d *_defer) {
-	d.link = nil
-	// After this point we can copy the stack.
-
-	if d._panic != nil {
-		freedeferpanic()
-	}
-	if d.fn != nil {
-		freedeferfn()
-	}
-	if !d.heap {
-		return
-	}
-
-	mp := acquirem()
-	pp := mp.p.ptr()
-	if len(pp.deferpool) == cap(pp.deferpool) {
-		// Transfer half of local cache to the central cache.
-		var first, last *_defer
-		for len(pp.deferpool) > cap(pp.deferpool)/2 {
-			n := len(pp.deferpool)
-			d := pp.deferpool[n-1]
-			pp.deferpool[n-1] = nil
-			pp.deferpool = pp.deferpool[:n-1]
-			if first == nil {
-				first = d
-			} else {
-				last.link = d
-			}
-			last = d
-		}
-		lock(&sched.deferlock)
-		last.link = sched.deferpool
-		sched.deferpool = first
-		unlock(&sched.deferlock)
-	}
-
-	*d = _defer{}
-
-	pp.deferpool = append(pp.deferpool, d)
-
-	releasem(mp)
-	mp, pp = nil, nil
-}
-
-// Separate function so that it can split stack.
-// Windows otherwise runs out of stack space.
-func freedeferpanic() {
-	// _panic must be cleared before d is unlinked from gp.
-	throw("freedefer with d._panic != nil")
-}
-
-func freedeferfn() {
-	// fn must be cleared before d is unlinked from gp.
-	throw("freedefer with d.fn != nil")
-}
-
-// deferreturn runs deferred functions for the caller's frame.
-// The compiler inserts a call to this at the end of any
-// function which calls defer.
-func deferreturn() {
-	gp := getg()
-	for {
-		d := gp._defer
-		if d == nil {
-			return
-		}
-		sp := getcallersp()
-		if d.sp != sp {
-			return
-		}
-		if d.openDefer {
-			done := runOpenDeferFrame(gp, d)
-			if !done {
-				throw("unfinished open-coded defers in deferreturn")
-			}
-			gp._defer = d.link
-			freedefer(d)
-			// If this frame uses open defers, then this
-			// must be the only defer record for the
-			// frame, so we can just return.
-			return
-		}
-
-		fn := d.fn
-		d.fn = nil
-		gp._defer = d.link
-		freedefer(d)
-		fn()
-	}
-}
-
-// Goexit terminates the goroutine that calls it. No other goroutine is affected.
-// Goexit runs all deferred calls before terminating the goroutine. Because Goexit
-// is not a panic, any recover calls in those deferred functions will return nil.
-//
-// Calling Goexit from the main goroutine terminates that goroutine
-// without func main returning. Since func main has not returned,
-// the program continues execution of other goroutines.
-// If all other goroutines exit, the program crashes.
-func Goexit() {
-	// Run all deferred functions for the current goroutine.
-	// This code is similar to gopanic, see that implementation
-	// for detailed comments.
-	gp := getg()
-
-	// Create a panic object for Goexit, so we can recognize when it might be
-	// bypassed by a recover().
-	var p _panic
-	p.goexit = true
-	p.link = gp._panic
-	gp._panic = (*_panic)(noescape(unsafe.Pointer(&p)))
-
-	addOneOpenDeferFrame(gp, getcallerpc(), unsafe.Pointer(getcallersp()))
-	for {
-		d := gp._defer
-		if d == nil {
-			break
-		}
-		if d.started {
-			if d._panic != nil {
-				d._panic.aborted = true
-				d._panic = nil
-			}
-			if !d.openDefer {
-				d.fn = nil
-				gp._defer = d.link
-				freedefer(d)
-				continue
-			}
-		}
-		d.started = true
-		d._panic = (*_panic)(noescape(unsafe.Pointer(&p)))
-		if d.openDefer {
-			done := runOpenDeferFrame(gp, d)
-			if !done {
-				// We should always run all defers in the frame,
-				// since there is no panic associated with this
-				// defer that can be recovered.
-				throw("unfinished open-coded defers in Goexit")
-			}
-			if p.aborted {
-				// Since our current defer caused a panic and may
-				// have been already freed, just restart scanning
-				// for open-coded defers from this frame again.
-				addOneOpenDeferFrame(gp, getcallerpc(), unsafe.Pointer(getcallersp()))
-			} else {
-				addOneOpenDeferFrame(gp, 0, nil)
-			}
-		} else {
-			// Save the pc/sp in deferCallSave(), so we can "recover" back to this
-			// loop if necessary.
-			deferCallSave(&p, d.fn)
-		}
-		if p.aborted {
-			// We had a recursive panic in the defer d we started, and
-			// then did a recover in a defer that was further down the
-			// defer chain than d. In the case of an outstanding Goexit,
-			// we force the recover to return back to this loop. d will
-			// have already been freed if completed, so just continue
-			// immediately to the next defer on the chain.
-			p.aborted = false
-			continue
-		}
-		if gp._defer != d {
-			throw("bad defer entry in Goexit")
-		}
-		d._panic = nil
-		d.fn = nil
-		gp._defer = d.link
-		freedefer(d)
-		// Note: we ignore recovers here because Goexit isn't a panic
-	}
-	goexit1()
-}
-
-// Call all Error and String methods before freezing the world.
-// Used when crashing with panicking.
-func preprintpanics(p *_panic) {
-	defer func() {
-		if recover() != nil {
-			throw("panic while printing panic value")
-		}
-	}()
-	for p != nil {
-		switch v := p.arg.(type) {
-		case error:
-			p.arg = v.Error()
-		case stringer:
-			p.arg = v.String()
-		}
-		p = p.link
-	}
-}
-
-// Print all currently active panics. Used when crashing.
-// Should only be called after preprintpanics.
-func printpanics(p *_panic) {
-	if p.link != nil {
-		printpanics(p.link)
-		if !p.link.goexit {
-			print("\t")
-		}
-	}
-	if p.goexit {
-		return
-	}
-	print("panic: ")
-	printany(p.arg)
-	if p.recovered {
-		print(" [recovered]")
-	}
-	print("\n")
-}
-
-// addOneOpenDeferFrame scans the stack (in gentraceback order, from inner frames to
-// outer frames) for the first frame (if any) with open-coded defers. If it finds
-// one, it adds a single entry to the defer chain for that frame. The entry added
-// represents all the defers in the associated open defer frame, and is sorted in
-// order with respect to any non-open-coded defers.
-//
-// addOneOpenDeferFrame stops (possibly without adding a new entry) if it encounters
-// an in-progress open defer entry. An in-progress open defer entry means there has
-// been a new panic because of a defer in the associated frame. addOneOpenDeferFrame
-// does not add an open defer entry past a started entry, because that started entry
-// still needs to finished, and addOneOpenDeferFrame will be called when that started
-// entry is completed. The defer removal loop in gopanic() similarly stops at an
-// in-progress defer entry. Together, addOneOpenDeferFrame and the defer removal loop
-// ensure the invariant that there is no open defer entry further up the stack than
-// an in-progress defer, and also that the defer removal loop is guaranteed to remove
-// all not-in-progress open defer entries from the defer chain.
-//
-// If sp is non-nil, addOneOpenDeferFrame starts the stack scan from the frame
-// specified by sp. If sp is nil, it uses the sp from the current defer record (which
-// has just been finished). Hence, it continues the stack scan from the frame of the
-// defer that just finished. It skips any frame that already has a (not-in-progress)
-// open-coded _defer record in the defer chain.
-//
-// Note: All entries of the defer chain (including this new open-coded entry) have
-// their pointers (including sp) adjusted properly if the stack moves while
-// running deferred functions. Also, it is safe to pass in the sp arg (which is
-// the direct result of calling getcallersp()), because all pointer variables
-// (including arguments) are adjusted as needed during stack copies.
-func addOneOpenDeferFrame(gp *g, pc uintptr, sp unsafe.Pointer) {
-	var prevDefer *_defer
-	if sp == nil {
-		prevDefer = gp._defer
-		pc = prevDefer.framepc
-		sp = unsafe.Pointer(prevDefer.sp)
-	}
-	systemstack(func() {
-		gentraceback(pc, uintptr(sp), 0, gp, 0, nil, 0x7fffffff,
-			func(frame *stkframe, unused unsafe.Pointer) bool {
-				if prevDefer != nil && prevDefer.sp == frame.sp {
-					// Skip the frame for the previous defer that
-					// we just finished (and was used to set
-					// where we restarted the stack scan)
-					return true
-				}
-				f := frame.fn
-				fd := funcdata(f, _FUNCDATA_OpenCodedDeferInfo)
-				if fd == nil {
-					return true
-				}
-				// Insert the open defer record in the
-				// chain, in order sorted by sp.
-				d := gp._defer
-				var prev *_defer
-				for d != nil {
-					dsp := d.sp
-					if frame.sp < dsp {
-						break
-					}
-					if frame.sp == dsp {
-						if !d.openDefer {
-							throw("duplicated defer entry")
-						}
-						// Don't add any record past an
-						// in-progress defer entry. We don't
-						// need it, and more importantly, we
-						// want to keep the invariant that
-						// there is no open defer entry
-						// passed an in-progress entry (see
-						// header comment).
-						if d.started {
-							return false
-						}
-						return true
-					}
-					prev = d
-					d = d.link
-				}
-				if frame.fn.deferreturn == 0 {
-					throw("missing deferreturn")
-				}
-
-				d1 := newdefer()
-				d1.openDefer = true
-				d1._panic = nil
-				// These are the pc/sp to set after we've
-				// run a defer in this frame that did a
-				// recover. We return to a special
-				// deferreturn that runs any remaining
-				// defers and then returns from the
-				// function.
-				d1.pc = frame.fn.entry() + uintptr(frame.fn.deferreturn)
-				d1.varp = frame.varp
-				d1.fd = fd
-				// Save the SP/PC associated with current frame,
-				// so we can continue stack trace later if needed.
-				d1.framepc = frame.pc
-				d1.sp = frame.sp
-				d1.link = d
-				if prev == nil {
-					gp._defer = d1
-				} else {
-					prev.link = d1
-				}
-				// Stop stack scanning after adding one open defer record
-				return false
-			},
-			nil, 0)
-	})
-}
-
-// readvarintUnsafe reads the uint32 in varint format starting at fd, and returns the
-// uint32 and a pointer to the byte following the varint.
-//
-// There is a similar function runtime.readvarint, which takes a slice of bytes,
-// rather than an unsafe pointer. These functions are duplicated, because one of
-// the two use cases for the functions would get slower if the functions were
-// combined.
-func readvarintUnsafe(fd unsafe.Pointer) (uint32, unsafe.Pointer) {
-	var r uint32
-	var shift int
-	for {
-		b := *(*uint8)((unsafe.Pointer(fd)))
-		fd = add(fd, unsafe.Sizeof(b))
-		if b < 128 {
-			return r + uint32(b)<<shift, fd
-		}
-		r += ((uint32(b) &^ 128) << shift)
-		shift += 7
-		if shift > 28 {
-			panic("Bad varint")
-		}
-	}
-}
-
-// runOpenDeferFrame runs the active open-coded defers in the frame specified by
-// d. It normally processes all active defers in the frame, but stops immediately
-// if a defer does a successful recover. It returns true if there are no
-// remaining defers to run in the frame.
-func runOpenDeferFrame(gp *g, d *_defer) bool {
-	done := true
-	fd := d.fd
-
-	deferBitsOffset, fd := readvarintUnsafe(fd)
-	nDefers, fd := readvarintUnsafe(fd)
-	deferBits := *(*uint8)(unsafe.Pointer(d.varp - uintptr(deferBitsOffset)))
-
-	for i := int(nDefers) - 1; i >= 0; i-- {
-		// read the funcdata info for this defer
-		var closureOffset uint32
-		closureOffset, fd = readvarintUnsafe(fd)
-		if deferBits&(1<<i) == 0 {
-			continue
-		}
-		closure := *(*func())(unsafe.Pointer(d.varp - uintptr(closureOffset)))
-		d.fn = closure
-		deferBits = deferBits &^ (1 << i)
-		*(*uint8)(unsafe.Pointer(d.varp - uintptr(deferBitsOffset))) = deferBits
-		p := d._panic
-		// Call the defer. Note that this can change d.varp if
-		// the stack moves.
-		deferCallSave(p, d.fn)
-		if p != nil && p.aborted {
-			break
-		}
-		d.fn = nil
-		if d._panic != nil && d._panic.recovered {
-			done = deferBits == 0
-			break
-		}
-	}
-
-	return done
-}
-
-// deferCallSave calls fn() after saving the caller's pc and sp in the
-// panic record. This allows the runtime to return to the Goexit defer
-// processing loop, in the unusual case where the Goexit may be
-// bypassed by a successful recover.
-//
-// This is marked as a wrapper by the compiler so it doesn't appear in
-// tracebacks.
-func deferCallSave(p *_panic, fn func()) {
-	if p != nil {
-		p.argp = unsafe.Pointer(getargp())
-		p.pc = getcallerpc()
-		p.sp = unsafe.Pointer(getcallersp())
-	}
-	fn()
-	if p != nil {
-		p.pc = 0
-		p.sp = unsafe.Pointer(nil)
-	}
-}
-
-// The implementation of the predeclared function panic.
-func gopanic(e any) {
-	gp := getg()
-	if gp.m.curg != gp {
-		print("panic: ")
-		printany(e)
-		print("\n")
-		throw("panic on system stack")
-	}
-
-	if gp.m.mallocing != 0 {
-		print("panic: ")
-		printany(e)
-		print("\n")
-		throw("panic during malloc")
-	}
-	if gp.m.preemptoff != "" {
-		print("panic: ")
-		printany(e)
-		print("\n")
-		print("preempt off reason: ")
-		print(gp.m.preemptoff)
-		print("\n")
-		throw("panic during preemptoff")
-	}
-	if gp.m.locks != 0 {
-		print("panic: ")
-		printany(e)
-		print("\n")
-		throw("panic holding locks")
-	}
-
-	var p _panic
-	p.arg = e
-	p.link = gp._panic
-	gp._panic = (*_panic)(noescape(unsafe.Pointer(&p)))
-
-	atomic.Xadd(&runningPanicDefers, 1)
-
-	// By calculating getcallerpc/getcallersp here, we avoid scanning the
-	// gopanic frame (stack scanning is slow...)
-	addOneOpenDeferFrame(gp, getcallerpc(), unsafe.Pointer(getcallersp()))
-
-	for {
-		d := gp._defer
-		if d == nil {
-			break
-		}
-
-		// If defer was started by earlier panic or Goexit (and, since we're back here, that triggered a new panic),
-		// take defer off list. An earlier panic will not continue running, but we will make sure below that an
-		// earlier Goexit does continue running.
-		if d.started {
-			if d._panic != nil {
-				d._panic.aborted = true
-			}
-			d._panic = nil
-			if !d.openDefer {
-				// For open-coded defers, we need to process the
-				// defer again, in case there are any other defers
-				// to call in the frame (not including the defer
-				// call that caused the panic).
-				d.fn = nil
-				gp._defer = d.link
-				freedefer(d)
-				continue
-			}
-		}
-
-		// Mark defer as started, but keep on list, so that traceback
-		// can find and update the defer's argument frame if stack growth
-		// or a garbage collection happens before executing d.fn.
-		d.started = true
-
-		// Record the panic that is running the defer.
-		// If there is a new panic during the deferred call, that panic
-		// will find d in the list and will mark d._panic (this panic) aborted.
-		d._panic = (*_panic)(noescape(unsafe.Pointer(&p)))
-
-		done := true
-		if d.openDefer {
-			done = runOpenDeferFrame(gp, d)
-			if done && !d._panic.recovered {
-				addOneOpenDeferFrame(gp, 0, nil)
-			}
-		} else {
-			p.argp = unsafe.Pointer(getargp())
-			d.fn()
-		}
-		p.argp = nil
-
-		// Deferred function did not panic. Remove d.
-		if gp._defer != d {
-			throw("bad defer entry in panic")
-		}
-		d._panic = nil
-
-		// trigger shrinkage to test stack copy. See stack_test.go:TestStackPanic
-		//GC()
-
-		pc := d.pc
-		sp := unsafe.Pointer(d.sp) // must be pointer so it gets adjusted during stack copy
-		if done {
-			d.fn = nil
-			gp._defer = d.link
-			freedefer(d)
-		}
-		if p.recovered {
-			gp._panic = p.link
-			if gp._panic != nil && gp._panic.goexit && gp._panic.aborted {
-				// A normal recover would bypass/abort the Goexit.  Instead,
-				// we return to the processing loop of the Goexit.
-				gp.sigcode0 = uintptr(gp._panic.sp)
-				gp.sigcode1 = uintptr(gp._panic.pc)
-				mcall(recovery)
-				throw("bypassed recovery failed") // mcall should not return
-			}
-			atomic.Xadd(&runningPanicDefers, -1)
-
-			// After a recover, remove any remaining non-started,
-			// open-coded defer entries, since the corresponding defers
-			// will be executed normally (inline). Any such entry will
-			// become stale once we run the corresponding defers inline
-			// and exit the associated stack frame. We only remove up to
-			// the first started (in-progress) open defer entry, not
-			// including the current frame, since any higher entries will
-			// be from a higher panic in progress, and will still be
-			// needed.
-			d := gp._defer
-			var prev *_defer
-			if !done {
-				// Skip our current frame, if not done. It is
-				// needed to complete any remaining defers in
-				// deferreturn()
-				prev = d
-				d = d.link
-			}
-			for d != nil {
-				if d.started {
-					// This defer is started but we
-					// are in the middle of a
-					// defer-panic-recover inside of
-					// it, so don't remove it or any
-					// further defer entries
-					break
-				}
-				if d.openDefer {
-					if prev == nil {
-						gp._defer = d.link
-					} else {
-						prev.link = d.link
-					}
-					newd := d.link
-					freedefer(d)
-					d = newd
-				} else {
-					prev = d
-					d = d.link
-				}
-			}
-
-			gp._panic = p.link
-			// Aborted panics are marked but remain on the g.panic list.
-			// Remove them from the list.
-			for gp._panic != nil && gp._panic.aborted {
-				gp._panic = gp._panic.link
-			}
-			if gp._panic == nil { // must be done with signal
-				gp.sig = 0
-			}
-			// Pass information about recovering frame to recovery.
-			gp.sigcode0 = uintptr(sp)
-			gp.sigcode1 = pc
-			mcall(recovery)
-			throw("recovery failed") // mcall should not return
-		}
-	}
-
-	// ran out of deferred calls - old-school panic now
-	// Because it is unsafe to call arbitrary user code after freezing
-	// the world, we call preprintpanics to invoke all necessary Error
-	// and String methods to prepare the panic strings before startpanic.
-	preprintpanics(gp._panic)
-
-	fatalpanic(gp._panic) // should not return
-	*(*int)(nil) = 0      // not reached
-}
-
-// getargp returns the location where the caller
-// writes outgoing function call arguments.
-//go:nosplit
-//go:noinline
-func getargp() uintptr {
-	return getcallersp() + sys.MinFrameSize
-}
-
-// The implementation of the predeclared function recover.
-// Cannot split the stack because it needs to reliably
-// find the stack segment of its caller.
-//
-// TODO(rsc): Once we commit to CopyStackAlways,
-// this doesn't need to be nosplit.
-//go:nosplit
-func gorecover(argp uintptr) any {
-	// Must be in a function running as part of a deferred call during the panic.
-	// Must be called from the topmost function of the call
-	// (the function used in the defer statement).
-	// p.argp is the argument pointer of that topmost deferred function call.
-	// Compare against argp reported by caller.
-	// If they match, the caller is the one who can recover.
-	gp := getg()
-	p := gp._panic
-	if p != nil && !p.goexit && !p.recovered && argp == uintptr(p.argp) {
-		p.recovered = true
-		return p.arg
-	}
-	return nil
-}
-
-//go:linkname sync_throw sync.throw
-func sync_throw(s string) {
-	throw(s)
-}
-
-//go:nosplit
-func throw(s string) {
-	// Everything throw does should be recursively nosplit so it
-	// can be called even when it's unsafe to grow the stack.
-	systemstack(func() {
-		print("fatal error: ", s, "\n")
-	})
-	gp := getg()
-	if gp.m.throwing == 0 {
-		gp.m.throwing = 1
-	}
-	fatalthrow()
-	*(*int)(nil) = 0 // not reached
-}
-
-// runningPanicDefers is non-zero while running deferred functions for panic.
-// runningPanicDefers is incremented and decremented atomically.
-// This is used to try hard to get a panic stack trace out when exiting.
-var runningPanicDefers uint32
-
-// panicking is non-zero when crashing the program for an unrecovered panic.
-// panicking is incremented and decremented atomically.
-var panicking uint32
-
-// paniclk is held while printing the panic information and stack trace,
-// so that two concurrent panics don't overlap their output.
-var paniclk mutex
-
-// Unwind the stack after a deferred function calls recover
-// after a panic. Then arrange to continue running as though
-// the caller of the deferred function returned normally.
-func recovery(gp *g) {
-	// Info about defer passed in G struct.
-	sp := gp.sigcode0
-	pc := gp.sigcode1
-
-	// d's arguments need to be in the stack.
-	if sp != 0 && (sp < gp.stack.lo || gp.stack.hi < sp) {
-		print("recover: ", hex(sp), " not in [", hex(gp.stack.lo), ", ", hex(gp.stack.hi), "]\n")
-		throw("bad recovery")
-	}
-
-	// Make the deferproc for this d return again,
-	// this time returning 1. The calling function will
-	// jump to the standard return epilogue.
-	gp.sched.sp = sp
-	gp.sched.pc = pc
-	gp.sched.lr = 0
-	gp.sched.ret = 1
-	gogo(&gp.sched)
-}
-
-// fatalthrow implements an unrecoverable runtime throw. It freezes the
-// system, prints stack traces starting from its caller, and terminates the
-// process.
-//
-//go:nosplit
-func fatalthrow() {
-	pc := getcallerpc()
-	sp := getcallersp()
-	gp := getg()
-	// Switch to the system stack to avoid any stack growth, which
-	// may make things worse if the runtime is in a bad state.
-	systemstack(func() {
-		startpanic_m()
-
-		if dopanic_m(gp, pc, sp) {
-			// crash uses a decent amount of nosplit stack and we're already
-			// low on stack in throw, so crash on the system stack (unlike
-			// fatalpanic).
-			crash()
-		}
-
-		exit(2)
-	})
-
-	*(*int)(nil) = 0 // not reached
-}
-
-// fatalpanic implements an unrecoverable panic. It is like fatalthrow, except
-// that if msgs != nil, fatalpanic also prints panic messages and decrements
-// runningPanicDefers once main is blocked from exiting.
-//
-//go:nosplit
-func fatalpanic(msgs *_panic) {
-	pc := getcallerpc()
-	sp := getcallersp()
-	gp := getg()
-	var docrash bool
-	// Switch to the system stack to avoid any stack growth, which
-	// may make things worse if the runtime is in a bad state.
-	systemstack(func() {
-		if startpanic_m() && msgs != nil {
-			// There were panic messages and startpanic_m
-			// says it's okay to try to print them.
-
-			// startpanic_m set panicking, which will
-			// block main from exiting, so now OK to
-			// decrement runningPanicDefers.
-			atomic.Xadd(&runningPanicDefers, -1)
-
-			printpanics(msgs)
-		}
-
-		docrash = dopanic_m(gp, pc, sp)
-	})
-
-	if docrash {
-		// By crashing outside the above systemstack call, debuggers
-		// will not be confused when generating a backtrace.
-		// Function crash is marked nosplit to avoid stack growth.
-		crash()
-	}
-
-	systemstack(func() {
-		exit(2)
-	})
-
-	*(*int)(nil) = 0 // not reached
-}
-
-// startpanic_m prepares for an unrecoverable panic.
-//
-// It returns true if panic messages should be printed, or false if
-// the runtime is in bad shape and should just print stacks.
-//
-// It must not have write barriers even though the write barrier
-// explicitly ignores writes once dying > 0. Write barriers still
-// assume that g.m.p != nil, and this function may not have P
-// in some contexts (e.g. a panic in a signal handler for a signal
-// sent to an M with no P).
-//
-//go:nowritebarrierrec
-func startpanic_m() bool {
-	_g_ := getg()
-	if mheap_.cachealloc.size == 0 { // very early
-		print("runtime: panic before malloc heap initialized\n")
-	}
-	// Disallow malloc during an unrecoverable panic. A panic
-	// could happen in a signal handler, or in a throw, or inside
-	// malloc itself. We want to catch if an allocation ever does
-	// happen (even if we're not in one of these situations).
-	_g_.m.mallocing++
-
-	// If we're dying because of a bad lock count, set it to a
-	// good lock count so we don't recursively panic below.
-	if _g_.m.locks < 0 {
-		_g_.m.locks = 1
-	}
-
-	switch _g_.m.dying {
-	case 0:
-		// Setting dying >0 has the side-effect of disabling this G's writebuf.
-		_g_.m.dying = 1
-		atomic.Xadd(&panicking, 1)
-		lock(&paniclk)
-		if debug.schedtrace > 0 || debug.scheddetail > 0 {
-			schedtrace(true)
-		}
-		freezetheworld()
-		return true
-	case 1:
-		// Something failed while panicking.
-		// Just print a stack trace and exit.
-		_g_.m.dying = 2
-		print("panic during panic\n")
-		return false
-	case 2:
-		// This is a genuine bug in the runtime, we couldn't even
-		// print the stack trace successfully.
-		_g_.m.dying = 3
-		print("stack trace unavailable\n")
-		exit(4)
-		fallthrough
-	default:
-		// Can't even print! Just exit.
-		exit(5)
-		return false // Need to return something.
-	}
-}
-
-var didothers bool
-var deadlock mutex
-
-func dopanic_m(gp *g, pc, sp uintptr) bool {
-	if gp.sig != 0 {
-		signame := signame(gp.sig)
-		if signame != "" {
-			print("[signal ", signame)
-		} else {
-			print("[signal ", hex(gp.sig))
-		}
-		print(" code=", hex(gp.sigcode0), " addr=", hex(gp.sigcode1), " pc=", hex(gp.sigpc), "]\n")
-	}
-
-	level, all, docrash := gotraceback()
-	_g_ := getg()
-	if level > 0 {
-		if gp != gp.m.curg {
-			all = true
-		}
-		if gp != gp.m.g0 {
-			print("\n")
-			goroutineheader(gp)
-			traceback(pc, sp, 0, gp)
-		} else if level >= 2 || _g_.m.throwing > 0 {
-			print("\nruntime stack:\n")
-			traceback(pc, sp, 0, gp)
-		}
-		if !didothers && all {
-			didothers = true
-			tracebackothers(gp)
-		}
-	}
-	unlock(&paniclk)
-
-	if atomic.Xadd(&panicking, -1) != 0 {
-		// Some other m is panicking too.
-		// Let it print what it needs to print.
-		// Wait forever without chewing up cpu.
-		// It will exit when it's done.
-		lock(&deadlock)
-		lock(&deadlock)
-	}
-
-	printDebugLog()
-
-	return docrash
-}
-
-// canpanic returns false if a signal should throw instead of
-// panicking.
-//
-//go:nosplit
-func canpanic(gp *g) bool {
-	// Note that g is m->gsignal, different from gp.
-	// Note also that g->m can change at preemption, so m can go stale
-	// if this function ever makes a function call.
-	_g_ := getg()
-	mp := _g_.m
-
-	// Is it okay for gp to panic instead of crashing the program?
-	// Yes, as long as it is running Go code, not runtime code,
-	// and not stuck in a system call.
-	if gp == nil || gp != mp.curg {
-		return false
-	}
-	if mp.locks != 0 || mp.mallocing != 0 || mp.throwing != 0 || mp.preemptoff != "" || mp.dying != 0 {
-		return false
-	}
-	status := readgstatus(gp)
-	if status&^_Gscan != _Grunning || gp.syscallsp != 0 {
-		return false
-	}
-	if GOOS == "windows" && mp.libcallsp != 0 {
-		return false
-	}
-	return true
-}
-
-// shouldPushSigpanic reports whether pc should be used as sigpanic's
-// return PC (pushing a frame for the call). Otherwise, it should be
-// left alone so that LR is used as sigpanic's return PC, effectively
-// replacing the top-most frame with sigpanic. This is used by
-// preparePanic.
-func shouldPushSigpanic(gp *g, pc, lr uintptr) bool {
-	if pc == 0 {
-		// Probably a call to a nil func. The old LR is more
-		// useful in the stack trace. Not pushing the frame
-		// will make the trace look like a call to sigpanic
-		// instead. (Otherwise the trace will end at sigpanic
-		// and we won't get to see who faulted.)
-		return false
-	}
-	// If we don't recognize the PC as code, but we do recognize
-	// the link register as code, then this assumes the panic was
-	// caused by a call to non-code. In this case, we want to
-	// ignore this call to make unwinding show the context.
-	//
-	// If we running C code, we're not going to recognize pc as a
-	// Go function, so just assume it's good. Otherwise, traceback
-	// may try to read a stale LR that looks like a Go code
-	// pointer and wander into the woods.
-	if gp.m.incgo || findfunc(pc).valid() {
-		// This wasn't a bad call, so use PC as sigpanic's
-		// return PC.
-		return true
-	}
-	if findfunc(lr).valid() {
-		// This was a bad call, but the LR is good, so use the
-		// LR as sigpanic's return PC.
-		return false
-	}
-	// Neither the PC or LR is good. Hopefully pushing a frame
-	// will work.
-	return true
-}
-
-// isAbortPC reports whether pc is the program counter at which
-// runtime.abort raises a signal.
-//
-// It is nosplit because it's part of the isgoexception
-// implementation.
-//
-//go:nosplit
-func isAbortPC(pc uintptr) bool {
-	f := findfunc(pc)
-	if !f.valid() {
-		return false
-	}
-	return f.funcID == funcID_abort
-}
diff --git a/contrib/go/_std_1.18/src/runtime/proc.go b/contrib/go/_std_1.18/src/runtime/proc.go
deleted file mode 100644
index b997a467ba..0000000000
--- a/contrib/go/_std_1.18/src/runtime/proc.go
+++ /dev/null
@@ -1,6244 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"internal/abi"
-	"internal/cpu"
-	"internal/goarch"
-	"runtime/internal/atomic"
-	"runtime/internal/sys"
-	"unsafe"
-)
-
-// set using cmd/go/internal/modload.ModInfoProg
-var modinfo string
-
-// Goroutine scheduler
-// The scheduler's job is to distribute ready-to-run goroutines over worker threads.
-//
-// The main concepts are:
-// G - goroutine.
-// M - worker thread, or machine.
-// P - processor, a resource that is required to execute Go code.
-//     M must have an associated P to execute Go code, however it can be
-//     blocked or in a syscall w/o an associated P.
-//
-// Design doc at https://golang.org/s/go11sched.
-
-// Worker thread parking/unparking.
-// We need to balance between keeping enough running worker threads to utilize
-// available hardware parallelism and parking excessive running worker threads
-// to conserve CPU resources and power. This is not simple for two reasons:
-// (1) scheduler state is intentionally distributed (in particular, per-P work
-// queues), so it is not possible to compute global predicates on fast paths;
-// (2) for optimal thread management we would need to know the future (don't park
-// a worker thread when a new goroutine will be readied in near future).
-//
-// Three rejected approaches that would work badly:
-// 1. Centralize all scheduler state (would inhibit scalability).
-// 2. Direct goroutine handoff. That is, when we ready a new goroutine and there
-//    is a spare P, unpark a thread and handoff it the thread and the goroutine.
-//    This would lead to thread state thrashing, as the thread that readied the
-//    goroutine can be out of work the very next moment, we will need to park it.
-//    Also, it would destroy locality of computation as we want to preserve
-//    dependent goroutines on the same thread; and introduce additional latency.
-// 3. Unpark an additional thread whenever we ready a goroutine and there is an
-//    idle P, but don't do handoff. This would lead to excessive thread parking/
-//    unparking as the additional threads will instantly park without discovering
-//    any work to do.
-//
-// The current approach:
-//
-// This approach applies to three primary sources of potential work: readying a
-// goroutine, new/modified-earlier timers, and idle-priority GC. See below for
-// additional details.
-//
-// We unpark an additional thread when we submit work if (this is wakep()):
-// 1. There is an idle P, and
-// 2. There are no "spinning" worker threads.
-//
-// A worker thread is considered spinning if it is out of local work and did
-// not find work in the global run queue or netpoller; the spinning state is
-// denoted in m.spinning and in sched.nmspinning. Threads unparked this way are
-// also considered spinning; we don't do goroutine handoff so such threads are
-// out of work initially. Spinning threads spin on looking for work in per-P
-// run queues and timer heaps or from the GC before parking. If a spinning
-// thread finds work it takes itself out of the spinning state and proceeds to
-// execution. If it does not find work it takes itself out of the spinning
-// state and then parks.
-//
-// If there is at least one spinning thread (sched.nmspinning>1), we don't
-// unpark new threads when submitting work. To compensate for that, if the last
-// spinning thread finds work and stops spinning, it must unpark a new spinning
-// thread.  This approach smooths out unjustified spikes of thread unparking,
-// but at the same time guarantees eventual maximal CPU parallelism
-// utilization.
-//
-// The main implementation complication is that we need to be very careful
-// during spinning->non-spinning thread transition. This transition can race
-// with submission of new work, and either one part or another needs to unpark
-// another worker thread. If they both fail to do that, we can end up with
-// semi-persistent CPU underutilization.
-//
-// The general pattern for submission is:
-// 1. Submit work to the local run queue, timer heap, or GC state.
-// 2. #StoreLoad-style memory barrier.
-// 3. Check sched.nmspinning.
-//
-// The general pattern for spinning->non-spinning transition is:
-// 1. Decrement nmspinning.
-// 2. #StoreLoad-style memory barrier.
-// 3. Check all per-P work queues and GC for new work.
-//
-// Note that all this complexity does not apply to global run queue as we are
-// not sloppy about thread unparking when submitting to global queue. Also see
-// comments for nmspinning manipulation.
-//
-// How these different sources of work behave varies, though it doesn't affect
-// the synchronization approach:
-// * Ready goroutine: this is an obvious source of work; the goroutine is
-//   immediately ready and must run on some thread eventually.
-// * New/modified-earlier timer: The current timer implementation (see time.go)
-//   uses netpoll in a thread with no work available to wait for the soonest
-//   timer. If there is no thread waiting, we want a new spinning thread to go
-//   wait.
-// * Idle-priority GC: The GC wakes a stopped idle thread to contribute to
-//   background GC work (note: currently disabled per golang.org/issue/19112).
-//   Also see golang.org/issue/44313, as this should be extended to all GC
-//   workers.
-
-var (
-	m0           m
-	g0           g
-	mcache0      *mcache
-	raceprocctx0 uintptr
-)
-
-//go:linkname runtime_inittask runtime..inittask
-var runtime_inittask initTask
-
-//go:linkname main_inittask main..inittask
-var main_inittask initTask
-
-// main_init_done is a signal used by cgocallbackg that initialization
-// has been completed. It is made before _cgo_notify_runtime_init_done,
-// so all cgo calls can rely on it existing. When main_init is complete,
-// it is closed, meaning cgocallbackg can reliably receive from it.
-var main_init_done chan bool
-
-//go:linkname main_main main.main
-func main_main()
-
-// mainStarted indicates that the main M has started.
-var mainStarted bool
-
-// runtimeInitTime is the nanotime() at which the runtime started.
-var runtimeInitTime int64
-
-// Value to use for signal mask for newly created M's.
-var initSigmask sigset
-
-// The main goroutine.
-func main() {
-	g := getg()
-
-	// Racectx of m0->g0 is used only as the parent of the main goroutine.
-	// It must not be used for anything else.
-	g.m.g0.racectx = 0
-
-	// Max stack size is 1 GB on 64-bit, 250 MB on 32-bit.
-	// Using decimal instead of binary GB and MB because
-	// they look nicer in the stack overflow failure message.
-	if goarch.PtrSize == 8 {
-		maxstacksize = 1000000000
-	} else {
-		maxstacksize = 250000000
-	}
-
-	// An upper limit for max stack size. Used to avoid random crashes
-	// after calling SetMaxStack and trying to allocate a stack that is too big,
-	// since stackalloc works with 32-bit sizes.
-	maxstackceiling = 2 * maxstacksize
-
-	// Allow newproc to start new Ms.
-	mainStarted = true
-
-	if GOARCH != "wasm" { // no threads on wasm yet, so no sysmon
-		systemstack(func() {
-			newm(sysmon, nil, -1)
-		})
-	}
-
-	// Lock the main goroutine onto this, the main OS thread,
-	// during initialization. Most programs won't care, but a few
-	// do require certain calls to be made by the main thread.
-	// Those can arrange for main.main to run in the main thread
-	// by calling runtime.LockOSThread during initialization
-	// to preserve the lock.
-	lockOSThread()
-
-	if g.m != &m0 {
-		throw("runtime.main not on m0")
-	}
-
-	// Record when the world started.
-	// Must be before doInit for tracing init.
-	runtimeInitTime = nanotime()
-	if runtimeInitTime == 0 {
-		throw("nanotime returning zero")
-	}
-
-	if debug.inittrace != 0 {
-		inittrace.id = getg().goid
-		inittrace.active = true
-	}
-
-	doInit(&runtime_inittask) // Must be before defer.
-
-	// Defer unlock so that runtime.Goexit during init does the unlock too.
-	needUnlock := true
-	defer func() {
-		if needUnlock {
-			unlockOSThread()
-		}
-	}()
-
-	gcenable()
-
-	main_init_done = make(chan bool)
-	if iscgo {
-		if _cgo_thread_start == nil {
-			throw("_cgo_thread_start missing")
-		}
-		if GOOS != "windows" {
-			if _cgo_setenv == nil {
-				throw("_cgo_setenv missing")
-			}
-			if _cgo_unsetenv == nil {
-				throw("_cgo_unsetenv missing")
-			}
-		}
-		if _cgo_notify_runtime_init_done == nil {
-			throw("_cgo_notify_runtime_init_done missing")
-		}
-		// Start the template thread in case we enter Go from
-		// a C-created thread and need to create a new thread.
-		startTemplateThread()
-		cgocall(_cgo_notify_runtime_init_done, nil)
-	}
-
-	doInit(&main_inittask)
-
-	// Disable init tracing after main init done to avoid overhead
-	// of collecting statistics in malloc and newproc
-	inittrace.active = false
-
-	close(main_init_done)
-
-	needUnlock = false
-	unlockOSThread()
-
-	if isarchive || islibrary {
-		// A program compiled with -buildmode=c-archive or c-shared
-		// has a main, but it is not executed.
-		return
-	}
-	fn := main_main // make an indirect call, as the linker doesn't know the address of the main package when laying down the runtime
-	fn()
-	if raceenabled {
-		racefini()
-	}
-
-	// Make racy client program work: if panicking on
-	// another goroutine at the same time as main returns,
-	// let the other goroutine finish printing the panic trace.
-	// Once it does, it will exit. See issues 3934 and 20018.
-	if atomic.Load(&runningPanicDefers) != 0 {
-		// Running deferred functions should not take long.
-		for c := 0; c < 1000; c++ {
-			if atomic.Load(&runningPanicDefers) == 0 {
-				break
-			}
-			Gosched()
-		}
-	}
-	if atomic.Load(&panicking) != 0 {
-		gopark(nil, nil, waitReasonPanicWait, traceEvGoStop, 1)
-	}
-
-	exit(0)
-	for {
-		var x *int32
-		*x = 0
-	}
-}
-
-// os_beforeExit is called from os.Exit(0).
-//go:linkname os_beforeExit os.runtime_beforeExit
-func os_beforeExit() {
-	if raceenabled {
-		racefini()
-	}
-}
-
-// start forcegc helper goroutine
-func init() {
-	go forcegchelper()
-}
-
-func forcegchelper() {
-	forcegc.g = getg()
-	lockInit(&forcegc.lock, lockRankForcegc)
-	for {
-		lock(&forcegc.lock)
-		if forcegc.idle != 0 {
-			throw("forcegc: phase error")
-		}
-		atomic.Store(&forcegc.idle, 1)
-		goparkunlock(&forcegc.lock, waitReasonForceGCIdle, traceEvGoBlock, 1)
-		// this goroutine is explicitly resumed by sysmon
-		if debug.gctrace > 0 {
-			println("GC forced")
-		}
-		// Time-triggered, fully concurrent.
-		gcStart(gcTrigger{kind: gcTriggerTime, now: nanotime()})
-	}
-}
-
-//go:nosplit
-
-// Gosched yields the processor, allowing other goroutines to run. It does not
-// suspend the current goroutine, so execution resumes automatically.
-func Gosched() {
-	checkTimeouts()
-	mcall(gosched_m)
-}
-
-// goschedguarded yields the processor like gosched, but also checks
-// for forbidden states and opts out of the yield in those cases.
-//go:nosplit
-func goschedguarded() {
-	mcall(goschedguarded_m)
-}
-
-// Puts the current goroutine into a waiting state and calls unlockf on the
-// system stack.
-//
-// If unlockf returns false, the goroutine is resumed.
-//
-// unlockf must not access this G's stack, as it may be moved between
-// the call to gopark and the call to unlockf.
-//
-// Note that because unlockf is called after putting the G into a waiting
-// state, the G may have already been readied by the time unlockf is called
-// unless there is external synchronization preventing the G from being
-// readied. If unlockf returns false, it must guarantee that the G cannot be
-// externally readied.
-//
-// Reason explains why the goroutine has been parked. It is displayed in stack
-// traces and heap dumps. Reasons should be unique and descriptive. Do not
-// re-use reasons, add new ones.
-func gopark(unlockf func(*g, unsafe.Pointer) bool, lock unsafe.Pointer, reason waitReason, traceEv byte, traceskip int) {
-	if reason != waitReasonSleep {
-		checkTimeouts() // timeouts may expire while two goroutines keep the scheduler busy
-	}
-	mp := acquirem()
-	gp := mp.curg
-	status := readgstatus(gp)
-	if status != _Grunning && status != _Gscanrunning {
-		throw("gopark: bad g status")
-	}
-	mp.waitlock = lock
-	mp.waitunlockf = unlockf
-	gp.waitreason = reason
-	mp.waittraceev = traceEv
-	mp.waittraceskip = traceskip
-	releasem(mp)
-	// can't do anything that might move the G between Ms here.
-	mcall(park_m)
-}
-
-// Puts the current goroutine into a waiting state and unlocks the lock.
-// The goroutine can be made runnable again by calling goready(gp).
-func goparkunlock(lock *mutex, reason waitReason, traceEv byte, traceskip int) {
-	gopark(parkunlock_c, unsafe.Pointer(lock), reason, traceEv, traceskip)
-}
-
-func goready(gp *g, traceskip int) {
-	systemstack(func() {
-		ready(gp, traceskip, true)
-	})
-}
-
-//go:nosplit
-func acquireSudog() *sudog {
-	// Delicate dance: the semaphore implementation calls
-	// acquireSudog, acquireSudog calls new(sudog),
-	// new calls malloc, malloc can call the garbage collector,
-	// and the garbage collector calls the semaphore implementation
-	// in stopTheWorld.
-	// Break the cycle by doing acquirem/releasem around new(sudog).
-	// The acquirem/releasem increments m.locks during new(sudog),
-	// which keeps the garbage collector from being invoked.
-	mp := acquirem()
-	pp := mp.p.ptr()
-	if len(pp.sudogcache) == 0 {
-		lock(&sched.sudoglock)
-		// First, try to grab a batch from central cache.
-		for len(pp.sudogcache) < cap(pp.sudogcache)/2 && sched.sudogcache != nil {
-			s := sched.sudogcache
-			sched.sudogcache = s.next
-			s.next = nil
-			pp.sudogcache = append(pp.sudogcache, s)
-		}
-		unlock(&sched.sudoglock)
-		// If the central cache is empty, allocate a new one.
-		if len(pp.sudogcache) == 0 {
-			pp.sudogcache = append(pp.sudogcache, new(sudog))
-		}
-	}
-	n := len(pp.sudogcache)
-	s := pp.sudogcache[n-1]
-	pp.sudogcache[n-1] = nil
-	pp.sudogcache = pp.sudogcache[:n-1]
-	if s.elem != nil {
-		throw("acquireSudog: found s.elem != nil in cache")
-	}
-	releasem(mp)
-	return s
-}
-
-//go:nosplit
-func releaseSudog(s *sudog) {
-	if s.elem != nil {
-		throw("runtime: sudog with non-nil elem")
-	}
-	if s.isSelect {
-		throw("runtime: sudog with non-false isSelect")
-	}
-	if s.next != nil {
-		throw("runtime: sudog with non-nil next")
-	}
-	if s.prev != nil {
-		throw("runtime: sudog with non-nil prev")
-	}
-	if s.waitlink != nil {
-		throw("runtime: sudog with non-nil waitlink")
-	}
-	if s.c != nil {
-		throw("runtime: sudog with non-nil c")
-	}
-	gp := getg()
-	if gp.param != nil {
-		throw("runtime: releaseSudog with non-nil gp.param")
-	}
-	mp := acquirem() // avoid rescheduling to another P
-	pp := mp.p.ptr()
-	if len(pp.sudogcache) == cap(pp.sudogcache) {
-		// Transfer half of local cache to the central cache.
-		var first, last *sudog
-		for len(pp.sudogcache) > cap(pp.sudogcache)/2 {
-			n := len(pp.sudogcache)
-			p := pp.sudogcache[n-1]
-			pp.sudogcache[n-1] = nil
-			pp.sudogcache = pp.sudogcache[:n-1]
-			if first == nil {
-				first = p
-			} else {
-				last.next = p
-			}
-			last = p
-		}
-		lock(&sched.sudoglock)
-		last.next = sched.sudogcache
-		sched.sudogcache = first
-		unlock(&sched.sudoglock)
-	}
-	pp.sudogcache = append(pp.sudogcache, s)
-	releasem(mp)
-}
-
-// called from assembly
-func badmcall(fn func(*g)) {
-	throw("runtime: mcall called on m->g0 stack")
-}
-
-func badmcall2(fn func(*g)) {
-	throw("runtime: mcall function returned")
-}
-
-func badreflectcall() {
-	panic(plainError("arg size to reflect.call more than 1GB"))
-}
-
-var badmorestackg0Msg = "fatal: morestack on g0\n"
-
-//go:nosplit
-//go:nowritebarrierrec
-func badmorestackg0() {
-	sp := stringStructOf(&badmorestackg0Msg)
-	write(2, sp.str, int32(sp.len))
-}
-
-var badmorestackgsignalMsg = "fatal: morestack on gsignal\n"
-
-//go:nosplit
-//go:nowritebarrierrec
-func badmorestackgsignal() {
-	sp := stringStructOf(&badmorestackgsignalMsg)
-	write(2, sp.str, int32(sp.len))
-}
-
-//go:nosplit
-func badctxt() {
-	throw("ctxt != 0")
-}
-
-func lockedOSThread() bool {
-	gp := getg()
-	return gp.lockedm != 0 && gp.m.lockedg != 0
-}
-
-var (
-	// allgs contains all Gs ever created (including dead Gs), and thus
-	// never shrinks.
-	//
-	// Access via the slice is protected by allglock or stop-the-world.
-	// Readers that cannot take the lock may (carefully!) use the atomic
-	// variables below.
-	allglock mutex
-	allgs    []*g
-
-	// allglen and allgptr are atomic variables that contain len(allgs) and
-	// &allgs[0] respectively. Proper ordering depends on totally-ordered
-	// loads and stores. Writes are protected by allglock.
-	//
-	// allgptr is updated before allglen. Readers should read allglen
-	// before allgptr to ensure that allglen is always <= len(allgptr). New
-	// Gs appended during the race can be missed. For a consistent view of
-	// all Gs, allglock must be held.
-	//
-	// allgptr copies should always be stored as a concrete type or
-	// unsafe.Pointer, not uintptr, to ensure that GC can still reach it
-	// even if it points to a stale array.
-	allglen uintptr
-	allgptr **g
-)
-
-func allgadd(gp *g) {
-	if readgstatus(gp) == _Gidle {
-		throw("allgadd: bad status Gidle")
-	}
-
-	lock(&allglock)
-	allgs = append(allgs, gp)
-	if &allgs[0] != allgptr {
-		atomicstorep(unsafe.Pointer(&allgptr), unsafe.Pointer(&allgs[0]))
-	}
-	atomic.Storeuintptr(&allglen, uintptr(len(allgs)))
-	unlock(&allglock)
-}
-
-// allGsSnapshot returns a snapshot of the slice of all Gs.
-//
-// The world must be stopped or allglock must be held.
-func allGsSnapshot() []*g {
-	assertWorldStoppedOrLockHeld(&allglock)
-
-	// Because the world is stopped or allglock is held, allgadd
-	// cannot happen concurrently with this. allgs grows
-	// monotonically and existing entries never change, so we can
-	// simply return a copy of the slice header. For added safety,
-	// we trim everything past len because that can still change.
-	return allgs[:len(allgs):len(allgs)]
-}
-
-// atomicAllG returns &allgs[0] and len(allgs) for use with atomicAllGIndex.
-func atomicAllG() (**g, uintptr) {
-	length := atomic.Loaduintptr(&allglen)
-	ptr := (**g)(atomic.Loadp(unsafe.Pointer(&allgptr)))
-	return ptr, length
-}
-
-// atomicAllGIndex returns ptr[i] with the allgptr returned from atomicAllG.
-func atomicAllGIndex(ptr **g, i uintptr) *g {
-	return *(**g)(add(unsafe.Pointer(ptr), i*goarch.PtrSize))
-}
-
-// forEachG calls fn on every G from allgs.
-//
-// forEachG takes a lock to exclude concurrent addition of new Gs.
-func forEachG(fn func(gp *g)) {
-	lock(&allglock)
-	for _, gp := range allgs {
-		fn(gp)
-	}
-	unlock(&allglock)
-}
-
-// forEachGRace calls fn on every G from allgs.
-//
-// forEachGRace avoids locking, but does not exclude addition of new Gs during
-// execution, which may be missed.
-func forEachGRace(fn func(gp *g)) {
-	ptr, length := atomicAllG()
-	for i := uintptr(0); i < length; i++ {
-		gp := atomicAllGIndex(ptr, i)
-		fn(gp)
-	}
-	return
-}
-
-const (
-	// Number of goroutine ids to grab from sched.goidgen to local per-P cache at once.
-	// 16 seems to provide enough amortization, but other than that it's mostly arbitrary number.
-	_GoidCacheBatch = 16
-)
-
-// cpuinit extracts the environment variable GODEBUG from the environment on
-// Unix-like operating systems and calls internal/cpu.Initialize.
-func cpuinit() {
-	const prefix = "GODEBUG="
-	var env string
-
-	switch GOOS {
-	case "aix", "darwin", "ios", "dragonfly", "freebsd", "netbsd", "openbsd", "illumos", "solaris", "linux":
-		cpu.DebugOptions = true
-
-		// Similar to goenv_unix but extracts the environment value for
-		// GODEBUG directly.
-		// TODO(moehrmann): remove when general goenvs() can be called before cpuinit()
-		n := int32(0)
-		for argv_index(argv, argc+1+n) != nil {
-			n++
-		}
-
-		for i := int32(0); i < n; i++ {
-			p := argv_index(argv, argc+1+i)
-			s := *(*string)(unsafe.Pointer(&stringStruct{unsafe.Pointer(p), findnull(p)}))
-
-			if hasPrefix(s, prefix) {
-				env = gostring(p)[len(prefix):]
-				break
-			}
-		}
-	}
-
-	cpu.Initialize(env)
-
-	// Support cpu feature variables are used in code generated by the compiler
-	// to guard execution of instructions that can not be assumed to be always supported.
-	switch GOARCH {
-	case "386", "amd64":
-		x86HasPOPCNT = cpu.X86.HasPOPCNT
-		x86HasSSE41 = cpu.X86.HasSSE41
-		x86HasFMA = cpu.X86.HasFMA
-
-	case "arm":
-		armHasVFPv4 = cpu.ARM.HasVFPv4
-
-	case "arm64":
-		arm64HasATOMICS = cpu.ARM64.HasATOMICS
-	}
-}
-
-// The bootstrap sequence is:
-//
-//	call osinit
-//	call schedinit
-//	make & queue new G
-//	call runtime·mstart
-//
-// The new G calls runtime·main.
-func schedinit() {
-	lockInit(&sched.lock, lockRankSched)
-	lockInit(&sched.sysmonlock, lockRankSysmon)
-	lockInit(&sched.deferlock, lockRankDefer)
-	lockInit(&sched.sudoglock, lockRankSudog)
-	lockInit(&deadlock, lockRankDeadlock)
-	lockInit(&paniclk, lockRankPanic)
-	lockInit(&allglock, lockRankAllg)
-	lockInit(&allpLock, lockRankAllp)
-	lockInit(&reflectOffs.lock, lockRankReflectOffs)
-	lockInit(&finlock, lockRankFin)
-	lockInit(&trace.bufLock, lockRankTraceBuf)
-	lockInit(&trace.stringsLock, lockRankTraceStrings)
-	lockInit(&trace.lock, lockRankTrace)
-	lockInit(&cpuprof.lock, lockRankCpuprof)
-	lockInit(&trace.stackTab.lock, lockRankTraceStackTab)
-	// Enforce that this lock is always a leaf lock.
-	// All of this lock's critical sections should be
-	// extremely short.
-	lockInit(&memstats.heapStats.noPLock, lockRankLeafRank)
-
-	// raceinit must be the first call to race detector.
-	// In particular, it must be done before mallocinit below calls racemapshadow.
-	_g_ := getg()
-	if raceenabled {
-		_g_.racectx, raceprocctx0 = raceinit()
-	}
-
-	sched.maxmcount = 10000
-
-	// The world starts stopped.
-	worldStopped()
-
-	moduledataverify()
-	stackinit()
-	mallocinit()
-	cpuinit()      // must run before alginit
-	alginit()      // maps, hash, fastrand must not be used before this call
-	fastrandinit() // must run before mcommoninit
-	mcommoninit(_g_.m, -1)
-	modulesinit()   // provides activeModules
-	typelinksinit() // uses maps, activeModules
-	itabsinit()     // uses activeModules
-	stkobjinit()    // must run before GC starts
-
-	sigsave(&_g_.m.sigmask)
-	initSigmask = _g_.m.sigmask
-
-	if offset := unsafe.Offsetof(sched.timeToRun); offset%8 != 0 {
-		println(offset)
-		throw("sched.timeToRun not aligned to 8 bytes")
-	}
-
-	goargs()
-	goenvs()
-	parsedebugvars()
-	gcinit()
-
-	lock(&sched.lock)
-	sched.lastpoll = uint64(nanotime())
-	procs := ncpu
-	if n, ok := atoi32(gogetenv("GOMAXPROCS")); ok && n > 0 {
-		procs = n
-	}
-	if procresize(procs) != nil {
-		throw("unknown runnable goroutine during bootstrap")
-	}
-	unlock(&sched.lock)
-
-	// World is effectively started now, as P's can run.
-	worldStarted()
-
-	// For cgocheck > 1, we turn on the write barrier at all times
-	// and check all pointer writes. We can't do this until after
-	// procresize because the write barrier needs a P.
-	if debug.cgocheck > 1 {
-		writeBarrier.cgo = true
-		writeBarrier.enabled = true
-		for _, p := range allp {
-			p.wbBuf.reset()
-		}
-	}
-
-	if buildVersion == "" {
-		// Condition should never trigger. This code just serves
-		// to ensure runtime·buildVersion is kept in the resulting binary.
-		buildVersion = "unknown"
-	}
-	if len(modinfo) == 1 {
-		// Condition should never trigger. This code just serves
-		// to ensure runtime·modinfo is kept in the resulting binary.
-		modinfo = ""
-	}
-}
-
-func dumpgstatus(gp *g) {
-	_g_ := getg()
-	print("runtime: gp: gp=", gp, ", goid=", gp.goid, ", gp->atomicstatus=", readgstatus(gp), "\n")
-	print("runtime:  g:  g=", _g_, ", goid=", _g_.goid, ",  g->atomicstatus=", readgstatus(_g_), "\n")
-}
-
-// sched.lock must be held.
-func checkmcount() {
-	assertLockHeld(&sched.lock)
-
-	if mcount() > sched.maxmcount {
-		print("runtime: program exceeds ", sched.maxmcount, "-thread limit\n")
-		throw("thread exhaustion")
-	}
-}
-
-// mReserveID returns the next ID to use for a new m. This new m is immediately
-// considered 'running' by checkdead.
-//
-// sched.lock must be held.
-func mReserveID() int64 {
-	assertLockHeld(&sched.lock)
-
-	if sched.mnext+1 < sched.mnext {
-		throw("runtime: thread ID overflow")
-	}
-	id := sched.mnext
-	sched.mnext++
-	checkmcount()
-	return id
-}
-
-// Pre-allocated ID may be passed as 'id', or omitted by passing -1.
-func mcommoninit(mp *m, id int64) {
-	_g_ := getg()
-
-	// g0 stack won't make sense for user (and is not necessary unwindable).
-	if _g_ != _g_.m.g0 {
-		callers(1, mp.createstack[:])
-	}
-
-	lock(&sched.lock)
-
-	if id >= 0 {
-		mp.id = id
-	} else {
-		mp.id = mReserveID()
-	}
-
-	lo := uint32(int64Hash(uint64(mp.id), fastrandseed))
-	hi := uint32(int64Hash(uint64(cputicks()), ^fastrandseed))
-	if lo|hi == 0 {
-		hi = 1
-	}
-	// Same behavior as for 1.17.
-	// TODO: Simplify ths.
-	if goarch.BigEndian {
-		mp.fastrand = uint64(lo)<<32 | uint64(hi)
-	} else {
-		mp.fastrand = uint64(hi)<<32 | uint64(lo)
-	}
-
-	mpreinit(mp)
-	if mp.gsignal != nil {
-		mp.gsignal.stackguard1 = mp.gsignal.stack.lo + _StackGuard
-	}
-
-	// Add to allm so garbage collector doesn't free g->m
-	// when it is just in a register or thread-local storage.
-	mp.alllink = allm
-
-	// NumCgoCall() iterates over allm w/o schedlock,
-	// so we need to publish it safely.
-	atomicstorep(unsafe.Pointer(&allm), unsafe.Pointer(mp))
-	unlock(&sched.lock)
-
-	// Allocate memory to hold a cgo traceback if the cgo call crashes.
-	if iscgo || GOOS == "solaris" || GOOS == "illumos" || GOOS == "windows" {
-		mp.cgoCallers = new(cgoCallers)
-	}
-}
-
-var fastrandseed uintptr
-
-func fastrandinit() {
-	s := (*[unsafe.Sizeof(fastrandseed)]byte)(unsafe.Pointer(&fastrandseed))[:]
-	getRandomData(s)
-}
-
-// Mark gp ready to run.
-func ready(gp *g, traceskip int, next bool) {
-	if trace.enabled {
-		traceGoUnpark(gp, traceskip)
-	}
-
-	status := readgstatus(gp)
-
-	// Mark runnable.
-	_g_ := getg()
-	mp := acquirem() // disable preemption because it can be holding p in a local var
-	if status&^_Gscan != _Gwaiting {
-		dumpgstatus(gp)
-		throw("bad g->status in ready")
-	}
-
-	// status is Gwaiting or Gscanwaiting, make Grunnable and put on runq
-	casgstatus(gp, _Gwaiting, _Grunnable)
-	runqput(_g_.m.p.ptr(), gp, next)
-	wakep()
-	releasem(mp)
-}
-
-// freezeStopWait is a large value that freezetheworld sets
-// sched.stopwait to in order to request that all Gs permanently stop.
-const freezeStopWait = 0x7fffffff
-
-// freezing is set to non-zero if the runtime is trying to freeze the
-// world.
-var freezing uint32
-
-// Similar to stopTheWorld but best-effort and can be called several times.
-// There is no reverse operation, used during crashing.
-// This function must not lock any mutexes.
-func freezetheworld() {
-	atomic.Store(&freezing, 1)
-	// stopwait and preemption requests can be lost
-	// due to races with concurrently executing threads,
-	// so try several times
-	for i := 0; i < 5; i++ {
-		// this should tell the scheduler to not start any new goroutines
-		sched.stopwait = freezeStopWait
-		atomic.Store(&sched.gcwaiting, 1)
-		// this should stop running goroutines
-		if !preemptall() {
-			break // no running goroutines
-		}
-		usleep(1000)
-	}
-	// to be sure
-	usleep(1000)
-	preemptall()
-	usleep(1000)
-}
-
-// All reads and writes of g's status go through readgstatus, casgstatus
-// castogscanstatus, casfrom_Gscanstatus.
-//go:nosplit
-func readgstatus(gp *g) uint32 {
-	return atomic.Load(&gp.atomicstatus)
-}
-
-// The Gscanstatuses are acting like locks and this releases them.
-// If it proves to be a performance hit we should be able to make these
-// simple atomic stores but for now we are going to throw if
-// we see an inconsistent state.
-func casfrom_Gscanstatus(gp *g, oldval, newval uint32) {
-	success := false
-
-	// Check that transition is valid.
-	switch oldval {
-	default:
-		print("runtime: casfrom_Gscanstatus bad oldval gp=", gp, ", oldval=", hex(oldval), ", newval=", hex(newval), "\n")
-		dumpgstatus(gp)
-		throw("casfrom_Gscanstatus:top gp->status is not in scan state")
-	case _Gscanrunnable,
-		_Gscanwaiting,
-		_Gscanrunning,
-		_Gscansyscall,
-		_Gscanpreempted:
-		if newval == oldval&^_Gscan {
-			success = atomic.Cas(&gp.atomicstatus, oldval, newval)
-		}
-	}
-	if !success {
-		print("runtime: casfrom_Gscanstatus failed gp=", gp, ", oldval=", hex(oldval), ", newval=", hex(newval), "\n")
-		dumpgstatus(gp)
-		throw("casfrom_Gscanstatus: gp->status is not in scan state")
-	}
-	releaseLockRank(lockRankGscan)
-}
-
-// This will return false if the gp is not in the expected status and the cas fails.
-// This acts like a lock acquire while the casfromgstatus acts like a lock release.
-func castogscanstatus(gp *g, oldval, newval uint32) bool {
-	switch oldval {
-	case _Grunnable,
-		_Grunning,
-		_Gwaiting,
-		_Gsyscall:
-		if newval == oldval|_Gscan {
-			r := atomic.Cas(&gp.atomicstatus, oldval, newval)
-			if r {
-				acquireLockRank(lockRankGscan)
-			}
-			return r
-
-		}
-	}
-	print("runtime: castogscanstatus oldval=", hex(oldval), " newval=", hex(newval), "\n")
-	throw("castogscanstatus")
-	panic("not reached")
-}
-
-// If asked to move to or from a Gscanstatus this will throw. Use the castogscanstatus
-// and casfrom_Gscanstatus instead.
-// casgstatus will loop if the g->atomicstatus is in a Gscan status until the routine that
-// put it in the Gscan state is finished.
-//go:nosplit
-func casgstatus(gp *g, oldval, newval uint32) {
-	if (oldval&_Gscan != 0) || (newval&_Gscan != 0) || oldval == newval {
-		systemstack(func() {
-			print("runtime: casgstatus: oldval=", hex(oldval), " newval=", hex(newval), "\n")
-			throw("casgstatus: bad incoming values")
-		})
-	}
-
-	acquireLockRank(lockRankGscan)
-	releaseLockRank(lockRankGscan)
-
-	// See https://golang.org/cl/21503 for justification of the yield delay.
-	const yieldDelay = 5 * 1000
-	var nextYield int64
-
-	// loop if gp->atomicstatus is in a scan state giving
-	// GC time to finish and change the state to oldval.
-	for i := 0; !atomic.Cas(&gp.atomicstatus, oldval, newval); i++ {
-		if oldval == _Gwaiting && gp.atomicstatus == _Grunnable {
-			throw("casgstatus: waiting for Gwaiting but is Grunnable")
-		}
-		if i == 0 {
-			nextYield = nanotime() + yieldDelay
-		}
-		if nanotime() < nextYield {
-			for x := 0; x < 10 && gp.atomicstatus != oldval; x++ {
-				procyield(1)
-			}
-		} else {
-			osyield()
-			nextYield = nanotime() + yieldDelay/2
-		}
-	}
-
-	// Handle tracking for scheduling latencies.
-	if oldval == _Grunning {
-		// Track every 8th time a goroutine transitions out of running.
-		if gp.trackingSeq%gTrackingPeriod == 0 {
-			gp.tracking = true
-		}
-		gp.trackingSeq++
-	}
-	if gp.tracking {
-		if oldval == _Grunnable {
-			// We transitioned out of runnable, so measure how much
-			// time we spent in this state and add it to
-			// runnableTime.
-			now := nanotime()
-			gp.runnableTime += now - gp.runnableStamp
-			gp.runnableStamp = 0
-		}
-		if newval == _Grunnable {
-			// We just transitioned into runnable, so record what
-			// time that happened.
-			now := nanotime()
-			gp.runnableStamp = now
-		} else if newval == _Grunning {
-			// We're transitioning into running, so turn off
-			// tracking and record how much time we spent in
-			// runnable.
-			gp.tracking = false
-			sched.timeToRun.record(gp.runnableTime)
-			gp.runnableTime = 0
-		}
-	}
-}
-
-// casgstatus(gp, oldstatus, Gcopystack), assuming oldstatus is Gwaiting or Grunnable.
-// Returns old status. Cannot call casgstatus directly, because we are racing with an
-// async wakeup that might come in from netpoll. If we see Gwaiting from the readgstatus,
-// it might have become Grunnable by the time we get to the cas. If we called casgstatus,
-// it would loop waiting for the status to go back to Gwaiting, which it never will.
-//go:nosplit
-func casgcopystack(gp *g) uint32 {
-	for {
-		oldstatus := readgstatus(gp) &^ _Gscan
-		if oldstatus != _Gwaiting && oldstatus != _Grunnable {
-			throw("copystack: bad status, not Gwaiting or Grunnable")
-		}
-		if atomic.Cas(&gp.atomicstatus, oldstatus, _Gcopystack) {
-			return oldstatus
-		}
-	}
-}
-
-// casGToPreemptScan transitions gp from _Grunning to _Gscan|_Gpreempted.
-//
-// TODO(austin): This is the only status operation that both changes
-// the status and locks the _Gscan bit. Rethink this.
-func casGToPreemptScan(gp *g, old, new uint32) {
-	if old != _Grunning || new != _Gscan|_Gpreempted {
-		throw("bad g transition")
-	}
-	acquireLockRank(lockRankGscan)
-	for !atomic.Cas(&gp.atomicstatus, _Grunning, _Gscan|_Gpreempted) {
-	}
-}
-
-// casGFromPreempted attempts to transition gp from _Gpreempted to
-// _Gwaiting. If successful, the caller is responsible for
-// re-scheduling gp.
-func casGFromPreempted(gp *g, old, new uint32) bool {
-	if old != _Gpreempted || new != _Gwaiting {
-		throw("bad g transition")
-	}
-	return atomic.Cas(&gp.atomicstatus, _Gpreempted, _Gwaiting)
-}
-
-// stopTheWorld stops all P's from executing goroutines, interrupting
-// all goroutines at GC safe points and records reason as the reason
-// for the stop. On return, only the current goroutine's P is running.
-// stopTheWorld must not be called from a system stack and the caller
-// must not hold worldsema. The caller must call startTheWorld when
-// other P's should resume execution.
-//
-// stopTheWorld is safe for multiple goroutines to call at the
-// same time. Each will execute its own stop, and the stops will
-// be serialized.
-//
-// This is also used by routines that do stack dumps. If the system is
-// in panic or being exited, this may not reliably stop all
-// goroutines.
-func stopTheWorld(reason string) {
-	semacquire(&worldsema)
-	gp := getg()
-	gp.m.preemptoff = reason
-	systemstack(func() {
-		// Mark the goroutine which called stopTheWorld preemptible so its
-		// stack may be scanned.
-		// This lets a mark worker scan us while we try to stop the world
-		// since otherwise we could get in a mutual preemption deadlock.
-		// We must not modify anything on the G stack because a stack shrink
-		// may occur. A stack shrink is otherwise OK though because in order
-		// to return from this function (and to leave the system stack) we
-		// must have preempted all goroutines, including any attempting
-		// to scan our stack, in which case, any stack shrinking will
-		// have already completed by the time we exit.
-		casgstatus(gp, _Grunning, _Gwaiting)
-		stopTheWorldWithSema()
-		casgstatus(gp, _Gwaiting, _Grunning)
-	})
-}
-
-// startTheWorld undoes the effects of stopTheWorld.
-func startTheWorld() {
-	systemstack(func() { startTheWorldWithSema(false) })
-
-	// worldsema must be held over startTheWorldWithSema to ensure
-	// gomaxprocs cannot change while worldsema is held.
-	//
-	// Release worldsema with direct handoff to the next waiter, but
-	// acquirem so that semrelease1 doesn't try to yield our time.
-	//
-	// Otherwise if e.g. ReadMemStats is being called in a loop,
-	// it might stomp on other attempts to stop the world, such as
-	// for starting or ending GC. The operation this blocks is
-	// so heavy-weight that we should just try to be as fair as
-	// possible here.
-	//
-	// We don't want to just allow us to get preempted between now
-	// and releasing the semaphore because then we keep everyone
-	// (including, for example, GCs) waiting longer.
-	mp := acquirem()
-	mp.preemptoff = ""
-	semrelease1(&worldsema, true, 0)
-	releasem(mp)
-}
-
-// stopTheWorldGC has the same effect as stopTheWorld, but blocks
-// until the GC is not running. It also blocks a GC from starting
-// until startTheWorldGC is called.
-func stopTheWorldGC(reason string) {
-	semacquire(&gcsema)
-	stopTheWorld(reason)
-}
-
-// startTheWorldGC undoes the effects of stopTheWorldGC.
-func startTheWorldGC() {
-	startTheWorld()
-	semrelease(&gcsema)
-}
-
-// Holding worldsema grants an M the right to try to stop the world.
-var worldsema uint32 = 1
-
-// Holding gcsema grants the M the right to block a GC, and blocks
-// until the current GC is done. In particular, it prevents gomaxprocs
-// from changing concurrently.
-//
-// TODO(mknyszek): Once gomaxprocs and the execution tracer can handle
-// being changed/enabled during a GC, remove this.
-var gcsema uint32 = 1
-
-// stopTheWorldWithSema is the core implementation of stopTheWorld.
-// The caller is responsible for acquiring worldsema and disabling
-// preemption first and then should stopTheWorldWithSema on the system
-// stack:
-//
-//	semacquire(&worldsema, 0)
-//	m.preemptoff = "reason"
-//	systemstack(stopTheWorldWithSema)
-//
-// When finished, the caller must either call startTheWorld or undo
-// these three operations separately:
-//
-//	m.preemptoff = ""
-//	systemstack(startTheWorldWithSema)
-//	semrelease(&worldsema)
-//
-// It is allowed to acquire worldsema once and then execute multiple
-// startTheWorldWithSema/stopTheWorldWithSema pairs.
-// Other P's are able to execute between successive calls to
-// startTheWorldWithSema and stopTheWorldWithSema.
-// Holding worldsema causes any other goroutines invoking
-// stopTheWorld to block.
-func stopTheWorldWithSema() {
-	_g_ := getg()
-
-	// If we hold a lock, then we won't be able to stop another M
-	// that is blocked trying to acquire the lock.
-	if _g_.m.locks > 0 {
-		throw("stopTheWorld: holding locks")
-	}
-
-	lock(&sched.lock)
-	sched.stopwait = gomaxprocs
-	atomic.Store(&sched.gcwaiting, 1)
-	preemptall()
-	// stop current P
-	_g_.m.p.ptr().status = _Pgcstop // Pgcstop is only diagnostic.
-	sched.stopwait--
-	// try to retake all P's in Psyscall status
-	for _, p := range allp {
-		s := p.status
-		if s == _Psyscall && atomic.Cas(&p.status, s, _Pgcstop) {
-			if trace.enabled {
-				traceGoSysBlock(p)
-				traceProcStop(p)
-			}
-			p.syscalltick++
-			sched.stopwait--
-		}
-	}
-	// stop idle P's
-	for {
-		p := pidleget()
-		if p == nil {
-			break
-		}
-		p.status = _Pgcstop
-		sched.stopwait--
-	}
-	wait := sched.stopwait > 0
-	unlock(&sched.lock)
-
-	// wait for remaining P's to stop voluntarily
-	if wait {
-		for {
-			// wait for 100us, then try to re-preempt in case of any races
-			if notetsleep(&sched.stopnote, 100*1000) {
-				noteclear(&sched.stopnote)
-				break
-			}
-			preemptall()
-		}
-	}
-
-	// sanity checks
-	bad := ""
-	if sched.stopwait != 0 {
-		bad = "stopTheWorld: not stopped (stopwait != 0)"
-	} else {
-		for _, p := range allp {
-			if p.status != _Pgcstop {
-				bad = "stopTheWorld: not stopped (status != _Pgcstop)"
-			}
-		}
-	}
-	if atomic.Load(&freezing) != 0 {
-		// Some other thread is panicking. This can cause the
-		// sanity checks above to fail if the panic happens in
-		// the signal handler on a stopped thread. Either way,
-		// we should halt this thread.
-		lock(&deadlock)
-		lock(&deadlock)
-	}
-	if bad != "" {
-		throw(bad)
-	}
-
-	worldStopped()
-}
-
-func startTheWorldWithSema(emitTraceEvent bool) int64 {
-	assertWorldStopped()
-
-	mp := acquirem() // disable preemption because it can be holding p in a local var
-	if netpollinited() {
-		list := netpoll(0) // non-blocking
-		injectglist(&list)
-	}
-	lock(&sched.lock)
-
-	procs := gomaxprocs
-	if newprocs != 0 {
-		procs = newprocs
-		newprocs = 0
-	}
-	p1 := procresize(procs)
-	sched.gcwaiting = 0
-	if sched.sysmonwait != 0 {
-		sched.sysmonwait = 0
-		notewakeup(&sched.sysmonnote)
-	}
-	unlock(&sched.lock)
-
-	worldStarted()
-
-	for p1 != nil {
-		p := p1
-		p1 = p1.link.ptr()
-		if p.m != 0 {
-			mp := p.m.ptr()
-			p.m = 0
-			if mp.nextp != 0 {
-				throw("startTheWorld: inconsistent mp->nextp")
-			}
-			mp.nextp.set(p)
-			notewakeup(&mp.park)
-		} else {
-			// Start M to run P.  Do not start another M below.
-			newm(nil, p, -1)
-		}
-	}
-
-	// Capture start-the-world time before doing clean-up tasks.
-	startTime := nanotime()
-	if emitTraceEvent {
-		traceGCSTWDone()
-	}
-
-	// Wakeup an additional proc in case we have excessive runnable goroutines
-	// in local queues or in the global queue. If we don't, the proc will park itself.
-	// If we have lots of excessive work, resetspinning will unpark additional procs as necessary.
-	wakep()
-
-	releasem(mp)
-
-	return startTime
-}
-
-// usesLibcall indicates whether this runtime performs system calls
-// via libcall.
-func usesLibcall() bool {
-	switch GOOS {
-	case "aix", "darwin", "illumos", "ios", "solaris", "windows":
-		return true
-	case "openbsd":
-		return GOARCH == "386" || GOARCH == "amd64" || GOARCH == "arm" || GOARCH == "arm64"
-	}
-	return false
-}
-
-// mStackIsSystemAllocated indicates whether this runtime starts on a
-// system-allocated stack.
-func mStackIsSystemAllocated() bool {
-	switch GOOS {
-	case "aix", "darwin", "plan9", "illumos", "ios", "solaris", "windows":
-		return true
-	case "openbsd":
-		switch GOARCH {
-		case "386", "amd64", "arm", "arm64":
-			return true
-		}
-	}
-	return false
-}
-
-// mstart is the entry-point for new Ms.
-// It is written in assembly, uses ABI0, is marked TOPFRAME, and calls mstart0.
-func mstart()
-
-// mstart0 is the Go entry-point for new Ms.
-// This must not split the stack because we may not even have stack
-// bounds set up yet.
-//
-// May run during STW (because it doesn't have a P yet), so write
-// barriers are not allowed.
-//
-//go:nosplit
-//go:nowritebarrierrec
-func mstart0() {
-	_g_ := getg()
-
-	osStack := _g_.stack.lo == 0
-	if osStack {
-		// Initialize stack bounds from system stack.
-		// Cgo may have left stack size in stack.hi.
-		// minit may update the stack bounds.
-		//
-		// Note: these bounds may not be very accurate.
-		// We set hi to &size, but there are things above
-		// it. The 1024 is supposed to compensate this,
-		// but is somewhat arbitrary.
-		size := _g_.stack.hi
-		if size == 0 {
-			size = 8192 * sys.StackGuardMultiplier
-		}
-		_g_.stack.hi = uintptr(noescape(unsafe.Pointer(&size)))
-		_g_.stack.lo = _g_.stack.hi - size + 1024
-	}
-	// Initialize stack guard so that we can start calling regular
-	// Go code.
-	_g_.stackguard0 = _g_.stack.lo + _StackGuard
-	// This is the g0, so we can also call go:systemstack
-	// functions, which check stackguard1.
-	_g_.stackguard1 = _g_.stackguard0
-	mstart1()
-
-	// Exit this thread.
-	if mStackIsSystemAllocated() {
-		// Windows, Solaris, illumos, Darwin, AIX and Plan 9 always system-allocate
-		// the stack, but put it in _g_.stack before mstart,
-		// so the logic above hasn't set osStack yet.
-		osStack = true
-	}
-	mexit(osStack)
-}
-
-// The go:noinline is to guarantee the getcallerpc/getcallersp below are safe,
-// so that we can set up g0.sched to return to the call of mstart1 above.
-//go:noinline
-func mstart1() {
-	_g_ := getg()
-
-	if _g_ != _g_.m.g0 {
-		throw("bad runtime·mstart")
-	}
-
-	// Set up m.g0.sched as a label returning to just
-	// after the mstart1 call in mstart0 above, for use by goexit0 and mcall.
-	// We're never coming back to mstart1 after we call schedule,
-	// so other calls can reuse the current frame.
-	// And goexit0 does a gogo that needs to return from mstart1
-	// and let mstart0 exit the thread.
-	_g_.sched.g = guintptr(unsafe.Pointer(_g_))
-	_g_.sched.pc = getcallerpc()
-	_g_.sched.sp = getcallersp()
-
-	asminit()
-	minit()
-
-	// Install signal handlers; after minit so that minit can
-	// prepare the thread to be able to handle the signals.
-	if _g_.m == &m0 {
-		mstartm0()
-	}
-
-	if fn := _g_.m.mstartfn; fn != nil {
-		fn()
-	}
-
-	if _g_.m != &m0 {
-		acquirep(_g_.m.nextp.ptr())
-		_g_.m.nextp = 0
-	}
-	schedule()
-}
-
-// mstartm0 implements part of mstart1 that only runs on the m0.
-//
-// Write barriers are allowed here because we know the GC can't be
-// running yet, so they'll be no-ops.
-//
-//go:yeswritebarrierrec
-func mstartm0() {
-	// Create an extra M for callbacks on threads not created by Go.
-	// An extra M is also needed on Windows for callbacks created by
-	// syscall.NewCallback. See issue #6751 for details.
-	if (iscgo || GOOS == "windows") && !cgoHasExtraM {
-		cgoHasExtraM = true
-		newextram()
-	}
-	initsig(false)
-}
-
-// mPark causes a thread to park itself, returning once woken.
-//go:nosplit
-func mPark() {
-	gp := getg()
-	notesleep(&gp.m.park)
-	noteclear(&gp.m.park)
-}
-
-// mexit tears down and exits the current thread.
-//
-// Don't call this directly to exit the thread, since it must run at
-// the top of the thread stack. Instead, use gogo(&_g_.m.g0.sched) to
-// unwind the stack to the point that exits the thread.
-//
-// It is entered with m.p != nil, so write barriers are allowed. It
-// will release the P before exiting.
-//
-//go:yeswritebarrierrec
-func mexit(osStack bool) {
-	g := getg()
-	m := g.m
-
-	if m == &m0 {
-		// This is the main thread. Just wedge it.
-		//
-		// On Linux, exiting the main thread puts the process
-		// into a non-waitable zombie state. On Plan 9,
-		// exiting the main thread unblocks wait even though
-		// other threads are still running. On Solaris we can
-		// neither exitThread nor return from mstart. Other
-		// bad things probably happen on other platforms.
-		//
-		// We could try to clean up this M more before wedging
-		// it, but that complicates signal handling.
-		handoffp(releasep())
-		lock(&sched.lock)
-		sched.nmfreed++
-		checkdead()
-		unlock(&sched.lock)
-		mPark()
-		throw("locked m0 woke up")
-	}
-
-	sigblock(true)
-	unminit()
-
-	// Free the gsignal stack.
-	if m.gsignal != nil {
-		stackfree(m.gsignal.stack)
-		// On some platforms, when calling into VDSO (e.g. nanotime)
-		// we store our g on the gsignal stack, if there is one.
-		// Now the stack is freed, unlink it from the m, so we
-		// won't write to it when calling VDSO code.
-		m.gsignal = nil
-	}
-
-	// Remove m from allm.
-	lock(&sched.lock)
-	for pprev := &allm; *pprev != nil; pprev = &(*pprev).alllink {
-		if *pprev == m {
-			*pprev = m.alllink
-			goto found
-		}
-	}
-	throw("m not found in allm")
-found:
-	if !osStack {
-		// Delay reaping m until it's done with the stack.
-		//
-		// If this is using an OS stack, the OS will free it
-		// so there's no need for reaping.
-		atomic.Store(&m.freeWait, 1)
-		// Put m on the free list, though it will not be reaped until
-		// freeWait is 0. Note that the free list must not be linked
-		// through alllink because some functions walk allm without
-		// locking, so may be using alllink.
-		m.freelink = sched.freem
-		sched.freem = m
-	}
-	unlock(&sched.lock)
-
-	atomic.Xadd64(&ncgocall, int64(m.ncgocall))
-
-	// Release the P.
-	handoffp(releasep())
-	// After this point we must not have write barriers.
-
-	// Invoke the deadlock detector. This must happen after
-	// handoffp because it may have started a new M to take our
-	// P's work.
-	lock(&sched.lock)
-	sched.nmfreed++
-	checkdead()
-	unlock(&sched.lock)
-
-	if GOOS == "darwin" || GOOS == "ios" {
-		// Make sure pendingPreemptSignals is correct when an M exits.
-		// For #41702.
-		if atomic.Load(&m.signalPending) != 0 {
-			atomic.Xadd(&pendingPreemptSignals, -1)
-		}
-	}
-
-	// Destroy all allocated resources. After this is called, we may no
-	// longer take any locks.
-	mdestroy(m)
-
-	if osStack {
-		// Return from mstart and let the system thread
-		// library free the g0 stack and terminate the thread.
-		return
-	}
-
-	// mstart is the thread's entry point, so there's nothing to
-	// return to. Exit the thread directly. exitThread will clear
-	// m.freeWait when it's done with the stack and the m can be
-	// reaped.
-	exitThread(&m.freeWait)
-}
-
-// forEachP calls fn(p) for every P p when p reaches a GC safe point.
-// If a P is currently executing code, this will bring the P to a GC
-// safe point and execute fn on that P. If the P is not executing code
-// (it is idle or in a syscall), this will call fn(p) directly while
-// preventing the P from exiting its state. This does not ensure that
-// fn will run on every CPU executing Go code, but it acts as a global
-// memory barrier. GC uses this as a "ragged barrier."
-//
-// The caller must hold worldsema.
-//
-//go:systemstack
-func forEachP(fn func(*p)) {
-	mp := acquirem()
-	_p_ := getg().m.p.ptr()
-
-	lock(&sched.lock)
-	if sched.safePointWait != 0 {
-		throw("forEachP: sched.safePointWait != 0")
-	}
-	sched.safePointWait = gomaxprocs - 1
-	sched.safePointFn = fn
-
-	// Ask all Ps to run the safe point function.
-	for _, p := range allp {
-		if p != _p_ {
-			atomic.Store(&p.runSafePointFn, 1)
-		}
-	}
-	preemptall()
-
-	// Any P entering _Pidle or _Psyscall from now on will observe
-	// p.runSafePointFn == 1 and will call runSafePointFn when
-	// changing its status to _Pidle/_Psyscall.
-
-	// Run safe point function for all idle Ps. sched.pidle will
-	// not change because we hold sched.lock.
-	for p := sched.pidle.ptr(); p != nil; p = p.link.ptr() {
-		if atomic.Cas(&p.runSafePointFn, 1, 0) {
-			fn(p)
-			sched.safePointWait--
-		}
-	}
-
-	wait := sched.safePointWait > 0
-	unlock(&sched.lock)
-
-	// Run fn for the current P.
-	fn(_p_)
-
-	// Force Ps currently in _Psyscall into _Pidle and hand them
-	// off to induce safe point function execution.
-	for _, p := range allp {
-		s := p.status
-		if s == _Psyscall && p.runSafePointFn == 1 && atomic.Cas(&p.status, s, _Pidle) {
-			if trace.enabled {
-				traceGoSysBlock(p)
-				traceProcStop(p)
-			}
-			p.syscalltick++
-			handoffp(p)
-		}
-	}
-
-	// Wait for remaining Ps to run fn.
-	if wait {
-		for {
-			// Wait for 100us, then try to re-preempt in
-			// case of any races.
-			//
-			// Requires system stack.
-			if notetsleep(&sched.safePointNote, 100*1000) {
-				noteclear(&sched.safePointNote)
-				break
-			}
-			preemptall()
-		}
-	}
-	if sched.safePointWait != 0 {
-		throw("forEachP: not done")
-	}
-	for _, p := range allp {
-		if p.runSafePointFn != 0 {
-			throw("forEachP: P did not run fn")
-		}
-	}
-
-	lock(&sched.lock)
-	sched.safePointFn = nil
-	unlock(&sched.lock)
-	releasem(mp)
-}
-
-// runSafePointFn runs the safe point function, if any, for this P.
-// This should be called like
-//
-//     if getg().m.p.runSafePointFn != 0 {
-//         runSafePointFn()
-//     }
-//
-// runSafePointFn must be checked on any transition in to _Pidle or
-// _Psyscall to avoid a race where forEachP sees that the P is running
-// just before the P goes into _Pidle/_Psyscall and neither forEachP
-// nor the P run the safe-point function.
-func runSafePointFn() {
-	p := getg().m.p.ptr()
-	// Resolve the race between forEachP running the safe-point
-	// function on this P's behalf and this P running the
-	// safe-point function directly.
-	if !atomic.Cas(&p.runSafePointFn, 1, 0) {
-		return
-	}
-	sched.safePointFn(p)
-	lock(&sched.lock)
-	sched.safePointWait--
-	if sched.safePointWait == 0 {
-		notewakeup(&sched.safePointNote)
-	}
-	unlock(&sched.lock)
-}
-
-// When running with cgo, we call _cgo_thread_start
-// to start threads for us so that we can play nicely with
-// foreign code.
-var cgoThreadStart unsafe.Pointer
-
-type cgothreadstart struct {
-	g   guintptr
-	tls *uint64
-	fn  unsafe.Pointer
-}
-
-// Allocate a new m unassociated with any thread.
-// Can use p for allocation context if needed.
-// fn is recorded as the new m's m.mstartfn.
-// id is optional pre-allocated m ID. Omit by passing -1.
-//
-// This function is allowed to have write barriers even if the caller
-// isn't because it borrows _p_.
-//
-//go:yeswritebarrierrec
-func allocm(_p_ *p, fn func(), id int64) *m {
-	allocmLock.rlock()
-
-	// The caller owns _p_, but we may borrow (i.e., acquirep) it. We must
-	// disable preemption to ensure it is not stolen, which would make the
-	// caller lose ownership.
-	acquirem()
-
-	_g_ := getg()
-	if _g_.m.p == 0 {
-		acquirep(_p_) // temporarily borrow p for mallocs in this function
-	}
-
-	// Release the free M list. We need to do this somewhere and
-	// this may free up a stack we can use.
-	if sched.freem != nil {
-		lock(&sched.lock)
-		var newList *m
-		for freem := sched.freem; freem != nil; {
-			if freem.freeWait != 0 {
-				next := freem.freelink
-				freem.freelink = newList
-				newList = freem
-				freem = next
-				continue
-			}
-			// stackfree must be on the system stack, but allocm is
-			// reachable off the system stack transitively from
-			// startm.
-			systemstack(func() {
-				stackfree(freem.g0.stack)
-			})
-			freem = freem.freelink
-		}
-		sched.freem = newList
-		unlock(&sched.lock)
-	}
-
-	mp := new(m)
-	mp.mstartfn = fn
-	mcommoninit(mp, id)
-
-	// In case of cgo or Solaris or illumos or Darwin, pthread_create will make us a stack.
-	// Windows and Plan 9 will layout sched stack on OS stack.
-	if iscgo || mStackIsSystemAllocated() {
-		mp.g0 = malg(-1)
-	} else {
-		mp.g0 = malg(8192 * sys.StackGuardMultiplier)
-	}
-	mp.g0.m = mp
-
-	if _p_ == _g_.m.p.ptr() {
-		releasep()
-	}
-
-	releasem(_g_.m)
-	allocmLock.runlock()
-	return mp
-}
-
-// needm is called when a cgo callback happens on a
-// thread without an m (a thread not created by Go).
-// In this case, needm is expected to find an m to use
-// and return with m, g initialized correctly.
-// Since m and g are not set now (likely nil, but see below)
-// needm is limited in what routines it can call. In particular
-// it can only call nosplit functions (textflag 7) and cannot
-// do any scheduling that requires an m.
-//
-// In order to avoid needing heavy lifting here, we adopt
-// the following strategy: there is a stack of available m's
-// that can be stolen. Using compare-and-swap
-// to pop from the stack has ABA races, so we simulate
-// a lock by doing an exchange (via Casuintptr) to steal the stack
-// head and replace the top pointer with MLOCKED (1).
-// This serves as a simple spin lock that we can use even
-// without an m. The thread that locks the stack in this way
-// unlocks the stack by storing a valid stack head pointer.
-//
-// In order to make sure that there is always an m structure
-// available to be stolen, we maintain the invariant that there
-// is always one more than needed. At the beginning of the
-// program (if cgo is in use) the list is seeded with a single m.
-// If needm finds that it has taken the last m off the list, its job
-// is - once it has installed its own m so that it can do things like
-// allocate memory - to create a spare m and put it on the list.
-//
-// Each of these extra m's also has a g0 and a curg that are
-// pressed into service as the scheduling stack and current
-// goroutine for the duration of the cgo callback.
-//
-// When the callback is done with the m, it calls dropm to
-// put the m back on the list.
-//go:nosplit
-func needm() {
-	if (iscgo || GOOS == "windows") && !cgoHasExtraM {
-		// Can happen if C/C++ code calls Go from a global ctor.
-		// Can also happen on Windows if a global ctor uses a
-		// callback created by syscall.NewCallback. See issue #6751
-		// for details.
-		//
-		// Can not throw, because scheduler is not initialized yet.
-		write(2, unsafe.Pointer(&earlycgocallback[0]), int32(len(earlycgocallback)))
-		exit(1)
-	}
-
-	// Save and block signals before getting an M.
-	// The signal handler may call needm itself,
-	// and we must avoid a deadlock. Also, once g is installed,
-	// any incoming signals will try to execute,
-	// but we won't have the sigaltstack settings and other data
-	// set up appropriately until the end of minit, which will
-	// unblock the signals. This is the same dance as when
-	// starting a new m to run Go code via newosproc.
-	var sigmask sigset
-	sigsave(&sigmask)
-	sigblock(false)
-
-	// Lock extra list, take head, unlock popped list.
-	// nilokay=false is safe here because of the invariant above,
-	// that the extra list always contains or will soon contain
-	// at least one m.
-	mp := lockextra(false)
-
-	// Set needextram when we've just emptied the list,
-	// so that the eventual call into cgocallbackg will
-	// allocate a new m for the extra list. We delay the
-	// allocation until then so that it can be done
-	// after exitsyscall makes sure it is okay to be
-	// running at all (that is, there's no garbage collection
-	// running right now).
-	mp.needextram = mp.schedlink == 0
-	extraMCount--
-	unlockextra(mp.schedlink.ptr())
-
-	// Store the original signal mask for use by minit.
-	mp.sigmask = sigmask
-
-	// Install TLS on some platforms (previously setg
-	// would do this if necessary).
-	osSetupTLS(mp)
-
-	// Install g (= m->g0) and set the stack bounds
-	// to match the current stack. We don't actually know
-	// how big the stack is, like we don't know how big any
-	// scheduling stack is, but we assume there's at least 32 kB,
-	// which is more than enough for us.
-	setg(mp.g0)
-	_g_ := getg()
-	_g_.stack.hi = getcallersp() + 1024
-	_g_.stack.lo = getcallersp() - 32*1024
-	_g_.stackguard0 = _g_.stack.lo + _StackGuard
-
-	// Initialize this thread to use the m.
-	asminit()
-	minit()
-
-	// mp.curg is now a real goroutine.
-	casgstatus(mp.curg, _Gdead, _Gsyscall)
-	atomic.Xadd(&sched.ngsys, -1)
-}
-
-var earlycgocallback = []byte("fatal error: cgo callback before cgo call\n")
-
-// newextram allocates m's and puts them on the extra list.
-// It is called with a working local m, so that it can do things
-// like call schedlock and allocate.
-func newextram() {
-	c := atomic.Xchg(&extraMWaiters, 0)
-	if c > 0 {
-		for i := uint32(0); i < c; i++ {
-			oneNewExtraM()
-		}
-	} else {
-		// Make sure there is at least one extra M.
-		mp := lockextra(true)
-		unlockextra(mp)
-		if mp == nil {
-			oneNewExtraM()
-		}
-	}
-}
-
-// oneNewExtraM allocates an m and puts it on the extra list.
-func oneNewExtraM() {
-	// Create extra goroutine locked to extra m.
-	// The goroutine is the context in which the cgo callback will run.
-	// The sched.pc will never be returned to, but setting it to
-	// goexit makes clear to the traceback routines where
-	// the goroutine stack ends.
-	mp := allocm(nil, nil, -1)
-	gp := malg(4096)
-	gp.sched.pc = abi.FuncPCABI0(goexit) + sys.PCQuantum
-	gp.sched.sp = gp.stack.hi
-	gp.sched.sp -= 4 * goarch.PtrSize // extra space in case of reads slightly beyond frame
-	gp.sched.lr = 0
-	gp.sched.g = guintptr(unsafe.Pointer(gp))
-	gp.syscallpc = gp.sched.pc
-	gp.syscallsp = gp.sched.sp
-	gp.stktopsp = gp.sched.sp
-	// malg returns status as _Gidle. Change to _Gdead before
-	// adding to allg where GC can see it. We use _Gdead to hide
-	// this from tracebacks and stack scans since it isn't a
-	// "real" goroutine until needm grabs it.
-	casgstatus(gp, _Gidle, _Gdead)
-	gp.m = mp
-	mp.curg = gp
-	mp.lockedInt++
-	mp.lockedg.set(gp)
-	gp.lockedm.set(mp)
-	gp.goid = int64(atomic.Xadd64(&sched.goidgen, 1))
-	if raceenabled {
-		gp.racectx = racegostart(abi.FuncPCABIInternal(newextram) + sys.PCQuantum)
-	}
-	// put on allg for garbage collector
-	allgadd(gp)
-
-	// gp is now on the allg list, but we don't want it to be
-	// counted by gcount. It would be more "proper" to increment
-	// sched.ngfree, but that requires locking. Incrementing ngsys
-	// has the same effect.
-	atomic.Xadd(&sched.ngsys, +1)
-
-	// Add m to the extra list.
-	mnext := lockextra(true)
-	mp.schedlink.set(mnext)
-	extraMCount++
-	unlockextra(mp)
-}
-
-// dropm is called when a cgo callback has called needm but is now
-// done with the callback and returning back into the non-Go thread.
-// It puts the current m back onto the extra list.
-//
-// The main expense here is the call to signalstack to release the
-// m's signal stack, and then the call to needm on the next callback
-// from this thread. It is tempting to try to save the m for next time,
-// which would eliminate both these costs, but there might not be
-// a next time: the current thread (which Go does not control) might exit.
-// If we saved the m for that thread, there would be an m leak each time
-// such a thread exited. Instead, we acquire and release an m on each
-// call. These should typically not be scheduling operations, just a few
-// atomics, so the cost should be small.
-//
-// TODO(rsc): An alternative would be to allocate a dummy pthread per-thread
-// variable using pthread_key_create. Unlike the pthread keys we already use
-// on OS X, this dummy key would never be read by Go code. It would exist
-// only so that we could register at thread-exit-time destructor.
-// That destructor would put the m back onto the extra list.
-// This is purely a performance optimization. The current version,
-// in which dropm happens on each cgo call, is still correct too.
-// We may have to keep the current version on systems with cgo
-// but without pthreads, like Windows.
-func dropm() {
-	// Clear m and g, and return m to the extra list.
-	// After the call to setg we can only call nosplit functions
-	// with no pointer manipulation.
-	mp := getg().m
-
-	// Return mp.curg to dead state.
-	casgstatus(mp.curg, _Gsyscall, _Gdead)
-	mp.curg.preemptStop = false
-	atomic.Xadd(&sched.ngsys, +1)
-
-	// Block signals before unminit.
-	// Unminit unregisters the signal handling stack (but needs g on some systems).
-	// Setg(nil) clears g, which is the signal handler's cue not to run Go handlers.
-	// It's important not to try to handle a signal between those two steps.
-	sigmask := mp.sigmask
-	sigblock(false)
-	unminit()
-
-	mnext := lockextra(true)
-	extraMCount++
-	mp.schedlink.set(mnext)
-
-	setg(nil)
-
-	// Commit the release of mp.
-	unlockextra(mp)
-
-	msigrestore(sigmask)
-}
-
-// A helper function for EnsureDropM.
-func getm() uintptr {
-	return uintptr(unsafe.Pointer(getg().m))
-}
-
-var extram uintptr
-var extraMCount uint32 // Protected by lockextra
-var extraMWaiters uint32
-
-// lockextra locks the extra list and returns the list head.
-// The caller must unlock the list by storing a new list head
-// to extram. If nilokay is true, then lockextra will
-// return a nil list head if that's what it finds. If nilokay is false,
-// lockextra will keep waiting until the list head is no longer nil.
-//go:nosplit
-func lockextra(nilokay bool) *m {
-	const locked = 1
-
-	incr := false
-	for {
-		old := atomic.Loaduintptr(&extram)
-		if old == locked {
-			osyield_no_g()
-			continue
-		}
-		if old == 0 && !nilokay {
-			if !incr {
-				// Add 1 to the number of threads
-				// waiting for an M.
-				// This is cleared by newextram.
-				atomic.Xadd(&extraMWaiters, 1)
-				incr = true
-			}
-			usleep_no_g(1)
-			continue
-		}
-		if atomic.Casuintptr(&extram, old, locked) {
-			return (*m)(unsafe.Pointer(old))
-		}
-		osyield_no_g()
-		continue
-	}
-}
-
-//go:nosplit
-func unlockextra(mp *m) {
-	atomic.Storeuintptr(&extram, uintptr(unsafe.Pointer(mp)))
-}
-
-var (
-	// allocmLock is locked for read when creating new Ms in allocm and their
-	// addition to allm. Thus acquiring this lock for write blocks the
-	// creation of new Ms.
-	allocmLock rwmutex
-
-	// execLock serializes exec and clone to avoid bugs or unspecified
-	// behaviour around exec'ing while creating/destroying threads. See
-	// issue #19546.
-	execLock rwmutex
-)
-
-// newmHandoff contains a list of m structures that need new OS threads.
-// This is used by newm in situations where newm itself can't safely
-// start an OS thread.
-var newmHandoff struct {
-	lock mutex
-
-	// newm points to a list of M structures that need new OS
-	// threads. The list is linked through m.schedlink.
-	newm muintptr
-
-	// waiting indicates that wake needs to be notified when an m
-	// is put on the list.
-	waiting bool
-	wake    note
-
-	// haveTemplateThread indicates that the templateThread has
-	// been started. This is not protected by lock. Use cas to set
-	// to 1.
-	haveTemplateThread uint32
-}
-
-// Create a new m. It will start off with a call to fn, or else the scheduler.
-// fn needs to be static and not a heap allocated closure.
-// May run with m.p==nil, so write barriers are not allowed.
-//
-// id is optional pre-allocated m ID. Omit by passing -1.
-//go:nowritebarrierrec
-func newm(fn func(), _p_ *p, id int64) {
-	// allocm adds a new M to allm, but they do not start until created by
-	// the OS in newm1 or the template thread.
-	//
-	// doAllThreadsSyscall requires that every M in allm will eventually
-	// start and be signal-able, even with a STW.
-	//
-	// Disable preemption here until we start the thread to ensure that
-	// newm is not preempted between allocm and starting the new thread,
-	// ensuring that anything added to allm is guaranteed to eventually
-	// start.
-	acquirem()
-
-	mp := allocm(_p_, fn, id)
-	mp.nextp.set(_p_)
-	mp.sigmask = initSigmask
-	if gp := getg(); gp != nil && gp.m != nil && (gp.m.lockedExt != 0 || gp.m.incgo) && GOOS != "plan9" {
-		// We're on a locked M or a thread that may have been
-		// started by C. The kernel state of this thread may
-		// be strange (the user may have locked it for that
-		// purpose). We don't want to clone that into another
-		// thread. Instead, ask a known-good thread to create
-		// the thread for us.
-		//
-		// This is disabled on Plan 9. See golang.org/issue/22227.
-		//
-		// TODO: This may be unnecessary on Windows, which
-		// doesn't model thread creation off fork.
-		lock(&newmHandoff.lock)
-		if newmHandoff.haveTemplateThread == 0 {
-			throw("on a locked thread with no template thread")
-		}
-		mp.schedlink = newmHandoff.newm
-		newmHandoff.newm.set(mp)
-		if newmHandoff.waiting {
-			newmHandoff.waiting = false
-			notewakeup(&newmHandoff.wake)
-		}
-		unlock(&newmHandoff.lock)
-		// The M has not started yet, but the template thread does not
-		// participate in STW, so it will always process queued Ms and
-		// it is safe to releasem.
-		releasem(getg().m)
-		return
-	}
-	newm1(mp)
-	releasem(getg().m)
-}
-
-func newm1(mp *m) {
-	if iscgo {
-		var ts cgothreadstart
-		if _cgo_thread_start == nil {
-			throw("_cgo_thread_start missing")
-		}
-		ts.g.set(mp.g0)
-		ts.tls = (*uint64)(unsafe.Pointer(&mp.tls[0]))
-		ts.fn = unsafe.Pointer(abi.FuncPCABI0(mstart))
-		if msanenabled {
-			msanwrite(unsafe.Pointer(&ts), unsafe.Sizeof(ts))
-		}
-		if asanenabled {
-			asanwrite(unsafe.Pointer(&ts), unsafe.Sizeof(ts))
-		}
-		execLock.rlock() // Prevent process clone.
-		asmcgocall(_cgo_thread_start, unsafe.Pointer(&ts))
-		execLock.runlock()
-		return
-	}
-	execLock.rlock() // Prevent process clone.
-	newosproc(mp)
-	execLock.runlock()
-}
-
-// startTemplateThread starts the template thread if it is not already
-// running.
-//
-// The calling thread must itself be in a known-good state.
-func startTemplateThread() {
-	if GOARCH == "wasm" { // no threads on wasm yet
-		return
-	}
-
-	// Disable preemption to guarantee that the template thread will be
-	// created before a park once haveTemplateThread is set.
-	mp := acquirem()
-	if !atomic.Cas(&newmHandoff.haveTemplateThread, 0, 1) {
-		releasem(mp)
-		return
-	}
-	newm(templateThread, nil, -1)
-	releasem(mp)
-}
-
-// templateThread is a thread in a known-good state that exists solely
-// to start new threads in known-good states when the calling thread
-// may not be in a good state.
-//
-// Many programs never need this, so templateThread is started lazily
-// when we first enter a state that might lead to running on a thread
-// in an unknown state.
-//
-// templateThread runs on an M without a P, so it must not have write
-// barriers.
-//
-//go:nowritebarrierrec
-func templateThread() {
-	lock(&sched.lock)
-	sched.nmsys++
-	checkdead()
-	unlock(&sched.lock)
-
-	for {
-		lock(&newmHandoff.lock)
-		for newmHandoff.newm != 0 {
-			newm := newmHandoff.newm.ptr()
-			newmHandoff.newm = 0
-			unlock(&newmHandoff.lock)
-			for newm != nil {
-				next := newm.schedlink.ptr()
-				newm.schedlink = 0
-				newm1(newm)
-				newm = next
-			}
-			lock(&newmHandoff.lock)
-		}
-		newmHandoff.waiting = true
-		noteclear(&newmHandoff.wake)
-		unlock(&newmHandoff.lock)
-		notesleep(&newmHandoff.wake)
-	}
-}
-
-// Stops execution of the current m until new work is available.
-// Returns with acquired P.
-func stopm() {
-	_g_ := getg()
-
-	if _g_.m.locks != 0 {
-		throw("stopm holding locks")
-	}
-	if _g_.m.p != 0 {
-		throw("stopm holding p")
-	}
-	if _g_.m.spinning {
-		throw("stopm spinning")
-	}
-
-	lock(&sched.lock)
-	mput(_g_.m)
-	unlock(&sched.lock)
-	mPark()
-	acquirep(_g_.m.nextp.ptr())
-	_g_.m.nextp = 0
-}
-
-func mspinning() {
-	// startm's caller incremented nmspinning. Set the new M's spinning.
-	getg().m.spinning = true
-}
-
-// Schedules some M to run the p (creates an M if necessary).
-// If p==nil, tries to get an idle P, if no idle P's does nothing.
-// May run with m.p==nil, so write barriers are not allowed.
-// If spinning is set, the caller has incremented nmspinning and startm will
-// either decrement nmspinning or set m.spinning in the newly started M.
-//
-// Callers passing a non-nil P must call from a non-preemptible context. See
-// comment on acquirem below.
-//
-// Must not have write barriers because this may be called without a P.
-//go:nowritebarrierrec
-func startm(_p_ *p, spinning bool) {
-	// Disable preemption.
-	//
-	// Every owned P must have an owner that will eventually stop it in the
-	// event of a GC stop request. startm takes transient ownership of a P
-	// (either from argument or pidleget below) and transfers ownership to
-	// a started M, which will be responsible for performing the stop.
-	//
-	// Preemption must be disabled during this transient ownership,
-	// otherwise the P this is running on may enter GC stop while still
-	// holding the transient P, leaving that P in limbo and deadlocking the
-	// STW.
-	//
-	// Callers passing a non-nil P must already be in non-preemptible
-	// context, otherwise such preemption could occur on function entry to
-	// startm. Callers passing a nil P may be preemptible, so we must
-	// disable preemption before acquiring a P from pidleget below.
-	mp := acquirem()
-	lock(&sched.lock)
-	if _p_ == nil {
-		_p_ = pidleget()
-		if _p_ == nil {
-			unlock(&sched.lock)
-			if spinning {
-				// The caller incremented nmspinning, but there are no idle Ps,
-				// so it's okay to just undo the increment and give up.
-				if int32(atomic.Xadd(&sched.nmspinning, -1)) < 0 {
-					throw("startm: negative nmspinning")
-				}
-			}
-			releasem(mp)
-			return
-		}
-	}
-	nmp := mget()
-	if nmp == nil {
-		// No M is available, we must drop sched.lock and call newm.
-		// However, we already own a P to assign to the M.
-		//
-		// Once sched.lock is released, another G (e.g., in a syscall),
-		// could find no idle P while checkdead finds a runnable G but
-		// no running M's because this new M hasn't started yet, thus
-		// throwing in an apparent deadlock.
-		//
-		// Avoid this situation by pre-allocating the ID for the new M,
-		// thus marking it as 'running' before we drop sched.lock. This
-		// new M will eventually run the scheduler to execute any
-		// queued G's.
-		id := mReserveID()
-		unlock(&sched.lock)
-
-		var fn func()
-		if spinning {
-			// The caller incremented nmspinning, so set m.spinning in the new M.
-			fn = mspinning
-		}
-		newm(fn, _p_, id)
-		// Ownership transfer of _p_ committed by start in newm.
-		// Preemption is now safe.
-		releasem(mp)
-		return
-	}
-	unlock(&sched.lock)
-	if nmp.spinning {
-		throw("startm: m is spinning")
-	}
-	if nmp.nextp != 0 {
-		throw("startm: m has p")
-	}
-	if spinning && !runqempty(_p_) {
-		throw("startm: p has runnable gs")
-	}
-	// The caller incremented nmspinning, so set m.spinning in the new M.
-	nmp.spinning = spinning
-	nmp.nextp.set(_p_)
-	notewakeup(&nmp.park)
-	// Ownership transfer of _p_ committed by wakeup. Preemption is now
-	// safe.
-	releasem(mp)
-}
-
-// Hands off P from syscall or locked M.
-// Always runs without a P, so write barriers are not allowed.
-//go:nowritebarrierrec
-func handoffp(_p_ *p) {
-	// handoffp must start an M in any situation where
-	// findrunnable would return a G to run on _p_.
-
-	// if it has local work, start it straight away
-	if !runqempty(_p_) || sched.runqsize != 0 {
-		startm(_p_, false)
-		return
-	}
-	// if it has GC work, start it straight away
-	if gcBlackenEnabled != 0 && gcMarkWorkAvailable(_p_) {
-		startm(_p_, false)
-		return
-	}
-	// no local work, check that there are no spinning/idle M's,
-	// otherwise our help is not required
-	if atomic.Load(&sched.nmspinning)+atomic.Load(&sched.npidle) == 0 && atomic.Cas(&sched.nmspinning, 0, 1) { // TODO: fast atomic
-		startm(_p_, true)
-		return
-	}
-	lock(&sched.lock)
-	if sched.gcwaiting != 0 {
-		_p_.status = _Pgcstop
-		sched.stopwait--
-		if sched.stopwait == 0 {
-			notewakeup(&sched.stopnote)
-		}
-		unlock(&sched.lock)
-		return
-	}
-	if _p_.runSafePointFn != 0 && atomic.Cas(&_p_.runSafePointFn, 1, 0) {
-		sched.safePointFn(_p_)
-		sched.safePointWait--
-		if sched.safePointWait == 0 {
-			notewakeup(&sched.safePointNote)
-		}
-	}
-	if sched.runqsize != 0 {
-		unlock(&sched.lock)
-		startm(_p_, false)
-		return
-	}
-	// If this is the last running P and nobody is polling network,
-	// need to wakeup another M to poll network.
-	if sched.npidle == uint32(gomaxprocs-1) && atomic.Load64(&sched.lastpoll) != 0 {
-		unlock(&sched.lock)
-		startm(_p_, false)
-		return
-	}
-
-	// The scheduler lock cannot be held when calling wakeNetPoller below
-	// because wakeNetPoller may call wakep which may call startm.
-	when := nobarrierWakeTime(_p_)
-	pidleput(_p_)
-	unlock(&sched.lock)
-
-	if when != 0 {
-		wakeNetPoller(when)
-	}
-}
-
-// Tries to add one more P to execute G's.
-// Called when a G is made runnable (newproc, ready).
-func wakep() {
-	if atomic.Load(&sched.npidle) == 0 {
-		return
-	}
-	// be conservative about spinning threads
-	if atomic.Load(&sched.nmspinning) != 0 || !atomic.Cas(&sched.nmspinning, 0, 1) {
-		return
-	}
-	startm(nil, true)
-}
-
-// Stops execution of the current m that is locked to a g until the g is runnable again.
-// Returns with acquired P.
-func stoplockedm() {
-	_g_ := getg()
-
-	if _g_.m.lockedg == 0 || _g_.m.lockedg.ptr().lockedm.ptr() != _g_.m {
-		throw("stoplockedm: inconsistent locking")
-	}
-	if _g_.m.p != 0 {
-		// Schedule another M to run this p.
-		_p_ := releasep()
-		handoffp(_p_)
-	}
-	incidlelocked(1)
-	// Wait until another thread schedules lockedg again.
-	mPark()
-	status := readgstatus(_g_.m.lockedg.ptr())
-	if status&^_Gscan != _Grunnable {
-		print("runtime:stoplockedm: lockedg (atomicstatus=", status, ") is not Grunnable or Gscanrunnable\n")
-		dumpgstatus(_g_.m.lockedg.ptr())
-		throw("stoplockedm: not runnable")
-	}
-	acquirep(_g_.m.nextp.ptr())
-	_g_.m.nextp = 0
-}
-
-// Schedules the locked m to run the locked gp.
-// May run during STW, so write barriers are not allowed.
-//go:nowritebarrierrec
-func startlockedm(gp *g) {
-	_g_ := getg()
-
-	mp := gp.lockedm.ptr()
-	if mp == _g_.m {
-		throw("startlockedm: locked to me")
-	}
-	if mp.nextp != 0 {
-		throw("startlockedm: m has p")
-	}
-	// directly handoff current P to the locked m
-	incidlelocked(-1)
-	_p_ := releasep()
-	mp.nextp.set(_p_)
-	notewakeup(&mp.park)
-	stopm()
-}
-
-// Stops the current m for stopTheWorld.
-// Returns when the world is restarted.
-func gcstopm() {
-	_g_ := getg()
-
-	if sched.gcwaiting == 0 {
-		throw("gcstopm: not waiting for gc")
-	}
-	if _g_.m.spinning {
-		_g_.m.spinning = false
-		// OK to just drop nmspinning here,
-		// startTheWorld will unpark threads as necessary.
-		if int32(atomic.Xadd(&sched.nmspinning, -1)) < 0 {
-			throw("gcstopm: negative nmspinning")
-		}
-	}
-	_p_ := releasep()
-	lock(&sched.lock)
-	_p_.status = _Pgcstop
-	sched.stopwait--
-	if sched.stopwait == 0 {
-		notewakeup(&sched.stopnote)
-	}
-	unlock(&sched.lock)
-	stopm()
-}
-
-// Schedules gp to run on the current M.
-// If inheritTime is true, gp inherits the remaining time in the
-// current time slice. Otherwise, it starts a new time slice.
-// Never returns.
-//
-// Write barriers are allowed because this is called immediately after
-// acquiring a P in several places.
-//
-//go:yeswritebarrierrec
-func execute(gp *g, inheritTime bool) {
-	_g_ := getg()
-
-	// Assign gp.m before entering _Grunning so running Gs have an
-	// M.
-	_g_.m.curg = gp
-	gp.m = _g_.m
-	casgstatus(gp, _Grunnable, _Grunning)
-	gp.waitsince = 0
-	gp.preempt = false
-	gp.stackguard0 = gp.stack.lo + _StackGuard
-	if !inheritTime {
-		_g_.m.p.ptr().schedtick++
-	}
-
-	// Check whether the profiler needs to be turned on or off.
-	hz := sched.profilehz
-	if _g_.m.profilehz != hz {
-		setThreadCPUProfiler(hz)
-	}
-
-	if trace.enabled {
-		// GoSysExit has to happen when we have a P, but before GoStart.
-		// So we emit it here.
-		if gp.syscallsp != 0 && gp.sysblocktraced {
-			traceGoSysExit(gp.sysexitticks)
-		}
-		traceGoStart()
-	}
-
-	gogo(&gp.sched)
-}
-
-// Finds a runnable goroutine to execute.
-// Tries to steal from other P's, get g from local or global queue, poll network.
-func findrunnable() (gp *g, inheritTime bool) {
-	_g_ := getg()
-
-	// The conditions here and in handoffp must agree: if
-	// findrunnable would return a G to run, handoffp must start
-	// an M.
-
-top:
-	_p_ := _g_.m.p.ptr()
-	if sched.gcwaiting != 0 {
-		gcstopm()
-		goto top
-	}
-	if _p_.runSafePointFn != 0 {
-		runSafePointFn()
-	}
-
-	now, pollUntil, _ := checkTimers(_p_, 0)
-
-	if fingwait && fingwake {
-		if gp := wakefing(); gp != nil {
-			ready(gp, 0, true)
-		}
-	}
-	if *cgo_yield != nil {
-		asmcgocall(*cgo_yield, nil)
-	}
-
-	// local runq
-	if gp, inheritTime := runqget(_p_); gp != nil {
-		return gp, inheritTime
-	}
-
-	// global runq
-	if sched.runqsize != 0 {
-		lock(&sched.lock)
-		gp := globrunqget(_p_, 0)
-		unlock(&sched.lock)
-		if gp != nil {
-			return gp, false
-		}
-	}
-
-	// Poll network.
-	// This netpoll is only an optimization before we resort to stealing.
-	// We can safely skip it if there are no waiters or a thread is blocked
-	// in netpoll already. If there is any kind of logical race with that
-	// blocked thread (e.g. it has already returned from netpoll, but does
-	// not set lastpoll yet), this thread will do blocking netpoll below
-	// anyway.
-	if netpollinited() && atomic.Load(&netpollWaiters) > 0 && atomic.Load64(&sched.lastpoll) != 0 {
-		if list := netpoll(0); !list.empty() { // non-blocking
-			gp := list.pop()
-			injectglist(&list)
-			casgstatus(gp, _Gwaiting, _Grunnable)
-			if trace.enabled {
-				traceGoUnpark(gp, 0)
-			}
-			return gp, false
-		}
-	}
-
-	// Spinning Ms: steal work from other Ps.
-	//
-	// Limit the number of spinning Ms to half the number of busy Ps.
-	// This is necessary to prevent excessive CPU consumption when
-	// GOMAXPROCS>>1 but the program parallelism is low.
-	procs := uint32(gomaxprocs)
-	if _g_.m.spinning || 2*atomic.Load(&sched.nmspinning) < procs-atomic.Load(&sched.npidle) {
-		if !_g_.m.spinning {
-			_g_.m.spinning = true
-			atomic.Xadd(&sched.nmspinning, 1)
-		}
-
-		gp, inheritTime, tnow, w, newWork := stealWork(now)
-		now = tnow
-		if gp != nil {
-			// Successfully stole.
-			return gp, inheritTime
-		}
-		if newWork {
-			// There may be new timer or GC work; restart to
-			// discover.
-			goto top
-		}
-		if w != 0 && (pollUntil == 0 || w < pollUntil) {
-			// Earlier timer to wait for.
-			pollUntil = w
-		}
-	}
-
-	// We have nothing to do.
-	//
-	// If we're in the GC mark phase, can safely scan and blacken objects,
-	// and have work to do, run idle-time marking rather than give up the
-	// P.
-	if gcBlackenEnabled != 0 && gcMarkWorkAvailable(_p_) {
-		node := (*gcBgMarkWorkerNode)(gcBgMarkWorkerPool.pop())
-		if node != nil {
-			_p_.gcMarkWorkerMode = gcMarkWorkerIdleMode
-			gp := node.gp.ptr()
-			casgstatus(gp, _Gwaiting, _Grunnable)
-			if trace.enabled {
-				traceGoUnpark(gp, 0)
-			}
-			return gp, false
-		}
-	}
-
-	// wasm only:
-	// If a callback returned and no other goroutine is awake,
-	// then wake event handler goroutine which pauses execution
-	// until a callback was triggered.
-	gp, otherReady := beforeIdle(now, pollUntil)
-	if gp != nil {
-		casgstatus(gp, _Gwaiting, _Grunnable)
-		if trace.enabled {
-			traceGoUnpark(gp, 0)
-		}
-		return gp, false
-	}
-	if otherReady {
-		goto top
-	}
-
-	// Before we drop our P, make a snapshot of the allp slice,
-	// which can change underfoot once we no longer block
-	// safe-points. We don't need to snapshot the contents because
-	// everything up to cap(allp) is immutable.
-	allpSnapshot := allp
-	// Also snapshot masks. Value changes are OK, but we can't allow
-	// len to change out from under us.
-	idlepMaskSnapshot := idlepMask
-	timerpMaskSnapshot := timerpMask
-
-	// return P and block
-	lock(&sched.lock)
-	if sched.gcwaiting != 0 || _p_.runSafePointFn != 0 {
-		unlock(&sched.lock)
-		goto top
-	}
-	if sched.runqsize != 0 {
-		gp := globrunqget(_p_, 0)
-		unlock(&sched.lock)
-		return gp, false
-	}
-	if releasep() != _p_ {
-		throw("findrunnable: wrong p")
-	}
-	pidleput(_p_)
-	unlock(&sched.lock)
-
-	// Delicate dance: thread transitions from spinning to non-spinning
-	// state, potentially concurrently with submission of new work. We must
-	// drop nmspinning first and then check all sources again (with
-	// #StoreLoad memory barrier in between). If we do it the other way
-	// around, another thread can submit work after we've checked all
-	// sources but before we drop nmspinning; as a result nobody will
-	// unpark a thread to run the work.
-	//
-	// This applies to the following sources of work:
-	//
-	// * Goroutines added to a per-P run queue.
-	// * New/modified-earlier timers on a per-P timer heap.
-	// * Idle-priority GC work (barring golang.org/issue/19112).
-	//
-	// If we discover new work below, we need to restore m.spinning as a signal
-	// for resetspinning to unpark a new worker thread (because there can be more
-	// than one starving goroutine). However, if after discovering new work
-	// we also observe no idle Ps it is OK to skip unparking a new worker
-	// thread: the system is fully loaded so no spinning threads are required.
-	// Also see "Worker thread parking/unparking" comment at the top of the file.
-	wasSpinning := _g_.m.spinning
-	if _g_.m.spinning {
-		_g_.m.spinning = false
-		if int32(atomic.Xadd(&sched.nmspinning, -1)) < 0 {
-			throw("findrunnable: negative nmspinning")
-		}
-
-		// Note the for correctness, only the last M transitioning from
-		// spinning to non-spinning must perform these rechecks to
-		// ensure no missed work. We are performing it on every M that
-		// transitions as a conservative change to monitor effects on
-		// latency. See golang.org/issue/43997.
-
-		// Check all runqueues once again.
-		_p_ = checkRunqsNoP(allpSnapshot, idlepMaskSnapshot)
-		if _p_ != nil {
-			acquirep(_p_)
-			_g_.m.spinning = true
-			atomic.Xadd(&sched.nmspinning, 1)
-			goto top
-		}
-
-		// Check for idle-priority GC work again.
-		_p_, gp = checkIdleGCNoP()
-		if _p_ != nil {
-			acquirep(_p_)
-			_g_.m.spinning = true
-			atomic.Xadd(&sched.nmspinning, 1)
-
-			// Run the idle worker.
-			_p_.gcMarkWorkerMode = gcMarkWorkerIdleMode
-			casgstatus(gp, _Gwaiting, _Grunnable)
-			if trace.enabled {
-				traceGoUnpark(gp, 0)
-			}
-			return gp, false
-		}
-
-		// Finally, check for timer creation or expiry concurrently with
-		// transitioning from spinning to non-spinning.
-		//
-		// Note that we cannot use checkTimers here because it calls
-		// adjusttimers which may need to allocate memory, and that isn't
-		// allowed when we don't have an active P.
-		pollUntil = checkTimersNoP(allpSnapshot, timerpMaskSnapshot, pollUntil)
-	}
-
-	// Poll network until next timer.
-	if netpollinited() && (atomic.Load(&netpollWaiters) > 0 || pollUntil != 0) && atomic.Xchg64(&sched.lastpoll, 0) != 0 {
-		atomic.Store64(&sched.pollUntil, uint64(pollUntil))
-		if _g_.m.p != 0 {
-			throw("findrunnable: netpoll with p")
-		}
-		if _g_.m.spinning {
-			throw("findrunnable: netpoll with spinning")
-		}
-		delay := int64(-1)
-		if pollUntil != 0 {
-			if now == 0 {
-				now = nanotime()
-			}
-			delay = pollUntil - now
-			if delay < 0 {
-				delay = 0
-			}
-		}
-		if faketime != 0 {
-			// When using fake time, just poll.
-			delay = 0
-		}
-		list := netpoll(delay) // block until new work is available
-		atomic.Store64(&sched.pollUntil, 0)
-		atomic.Store64(&sched.lastpoll, uint64(nanotime()))
-		if faketime != 0 && list.empty() {
-			// Using fake time and nothing is ready; stop M.
-			// When all M's stop, checkdead will call timejump.
-			stopm()
-			goto top
-		}
-		lock(&sched.lock)
-		_p_ = pidleget()
-		unlock(&sched.lock)
-		if _p_ == nil {
-			injectglist(&list)
-		} else {
-			acquirep(_p_)
-			if !list.empty() {
-				gp := list.pop()
-				injectglist(&list)
-				casgstatus(gp, _Gwaiting, _Grunnable)
-				if trace.enabled {
-					traceGoUnpark(gp, 0)
-				}
-				return gp, false
-			}
-			if wasSpinning {
-				_g_.m.spinning = true
-				atomic.Xadd(&sched.nmspinning, 1)
-			}
-			goto top
-		}
-	} else if pollUntil != 0 && netpollinited() {
-		pollerPollUntil := int64(atomic.Load64(&sched.pollUntil))
-		if pollerPollUntil == 0 || pollerPollUntil > pollUntil {
-			netpollBreak()
-		}
-	}
-	stopm()
-	goto top
-}
-
-// pollWork reports whether there is non-background work this P could
-// be doing. This is a fairly lightweight check to be used for
-// background work loops, like idle GC. It checks a subset of the
-// conditions checked by the actual scheduler.
-func pollWork() bool {
-	if sched.runqsize != 0 {
-		return true
-	}
-	p := getg().m.p.ptr()
-	if !runqempty(p) {
-		return true
-	}
-	if netpollinited() && atomic.Load(&netpollWaiters) > 0 && sched.lastpoll != 0 {
-		if list := netpoll(0); !list.empty() {
-			injectglist(&list)
-			return true
-		}
-	}
-	return false
-}
-
-// stealWork attempts to steal a runnable goroutine or timer from any P.
-//
-// If newWork is true, new work may have been readied.
-//
-// If now is not 0 it is the current time. stealWork returns the passed time or
-// the current time if now was passed as 0.
-func stealWork(now int64) (gp *g, inheritTime bool, rnow, pollUntil int64, newWork bool) {
-	pp := getg().m.p.ptr()
-
-	ranTimer := false
-
-	const stealTries = 4
-	for i := 0; i < stealTries; i++ {
-		stealTimersOrRunNextG := i == stealTries-1
-
-		for enum := stealOrder.start(fastrand()); !enum.done(); enum.next() {
-			if sched.gcwaiting != 0 {
-				// GC work may be available.
-				return nil, false, now, pollUntil, true
-			}
-			p2 := allp[enum.position()]
-			if pp == p2 {
-				continue
-			}
-
-			// Steal timers from p2. This call to checkTimers is the only place
-			// where we might hold a lock on a different P's timers. We do this
-			// once on the last pass before checking runnext because stealing
-			// from the other P's runnext should be the last resort, so if there
-			// are timers to steal do that first.
-			//
-			// We only check timers on one of the stealing iterations because
-			// the time stored in now doesn't change in this loop and checking
-			// the timers for each P more than once with the same value of now
-			// is probably a waste of time.
-			//
-			// timerpMask tells us whether the P may have timers at all. If it
-			// can't, no need to check at all.
-			if stealTimersOrRunNextG && timerpMask.read(enum.position()) {
-				tnow, w, ran := checkTimers(p2, now)
-				now = tnow
-				if w != 0 && (pollUntil == 0 || w < pollUntil) {
-					pollUntil = w
-				}
-				if ran {
-					// Running the timers may have
-					// made an arbitrary number of G's
-					// ready and added them to this P's
-					// local run queue. That invalidates
-					// the assumption of runqsteal
-					// that it always has room to add
-					// stolen G's. So check now if there
-					// is a local G to run.
-					if gp, inheritTime := runqget(pp); gp != nil {
-						return gp, inheritTime, now, pollUntil, ranTimer
-					}
-					ranTimer = true
-				}
-			}
-
-			// Don't bother to attempt to steal if p2 is idle.
-			if !idlepMask.read(enum.position()) {
-				if gp := runqsteal(pp, p2, stealTimersOrRunNextG); gp != nil {
-					return gp, false, now, pollUntil, ranTimer
-				}
-			}
-		}
-	}
-
-	// No goroutines found to steal. Regardless, running a timer may have
-	// made some goroutine ready that we missed. Indicate the next timer to
-	// wait for.
-	return nil, false, now, pollUntil, ranTimer
-}
-
-// Check all Ps for a runnable G to steal.
-//
-// On entry we have no P. If a G is available to steal and a P is available,
-// the P is returned which the caller should acquire and attempt to steal the
-// work to.
-func checkRunqsNoP(allpSnapshot []*p, idlepMaskSnapshot pMask) *p {
-	for id, p2 := range allpSnapshot {
-		if !idlepMaskSnapshot.read(uint32(id)) && !runqempty(p2) {
-			lock(&sched.lock)
-			pp := pidleget()
-			unlock(&sched.lock)
-			if pp != nil {
-				return pp
-			}
-
-			// Can't get a P, don't bother checking remaining Ps.
-			break
-		}
-	}
-
-	return nil
-}
-
-// Check all Ps for a timer expiring sooner than pollUntil.
-//
-// Returns updated pollUntil value.
-func checkTimersNoP(allpSnapshot []*p, timerpMaskSnapshot pMask, pollUntil int64) int64 {
-	for id, p2 := range allpSnapshot {
-		if timerpMaskSnapshot.read(uint32(id)) {
-			w := nobarrierWakeTime(p2)
-			if w != 0 && (pollUntil == 0 || w < pollUntil) {
-				pollUntil = w
-			}
-		}
-	}
-
-	return pollUntil
-}
-
-// Check for idle-priority GC, without a P on entry.
-//
-// If some GC work, a P, and a worker G are all available, the P and G will be
-// returned. The returned P has not been wired yet.
-func checkIdleGCNoP() (*p, *g) {
-	// N.B. Since we have no P, gcBlackenEnabled may change at any time; we
-	// must check again after acquiring a P.
-	if atomic.Load(&gcBlackenEnabled) == 0 {
-		return nil, nil
-	}
-	if !gcMarkWorkAvailable(nil) {
-		return nil, nil
-	}
-
-	// Work is available; we can start an idle GC worker only if there is
-	// an available P and available worker G.
-	//
-	// We can attempt to acquire these in either order, though both have
-	// synchronization concerns (see below). Workers are almost always
-	// available (see comment in findRunnableGCWorker for the one case
-	// there may be none). Since we're slightly less likely to find a P,
-	// check for that first.
-	//
-	// Synchronization: note that we must hold sched.lock until we are
-	// committed to keeping it. Otherwise we cannot put the unnecessary P
-	// back in sched.pidle without performing the full set of idle
-	// transition checks.
-	//
-	// If we were to check gcBgMarkWorkerPool first, we must somehow handle
-	// the assumption in gcControllerState.findRunnableGCWorker that an
-	// empty gcBgMarkWorkerPool is only possible if gcMarkDone is running.
-	lock(&sched.lock)
-	pp := pidleget()
-	if pp == nil {
-		unlock(&sched.lock)
-		return nil, nil
-	}
-
-	// Now that we own a P, gcBlackenEnabled can't change (as it requires
-	// STW).
-	if gcBlackenEnabled == 0 {
-		pidleput(pp)
-		unlock(&sched.lock)
-		return nil, nil
-	}
-
-	node := (*gcBgMarkWorkerNode)(gcBgMarkWorkerPool.pop())
-	if node == nil {
-		pidleput(pp)
-		unlock(&sched.lock)
-		return nil, nil
-	}
-
-	unlock(&sched.lock)
-
-	return pp, node.gp.ptr()
-}
-
-// wakeNetPoller wakes up the thread sleeping in the network poller if it isn't
-// going to wake up before the when argument; or it wakes an idle P to service
-// timers and the network poller if there isn't one already.
-func wakeNetPoller(when int64) {
-	if atomic.Load64(&sched.lastpoll) == 0 {
-		// In findrunnable we ensure that when polling the pollUntil
-		// field is either zero or the time to which the current
-		// poll is expected to run. This can have a spurious wakeup
-		// but should never miss a wakeup.
-		pollerPollUntil := int64(atomic.Load64(&sched.pollUntil))
-		if pollerPollUntil == 0 || pollerPollUntil > when {
-			netpollBreak()
-		}
-	} else {
-		// There are no threads in the network poller, try to get
-		// one there so it can handle new timers.
-		if GOOS != "plan9" { // Temporary workaround - see issue #42303.
-			wakep()
-		}
-	}
-}
-
-func resetspinning() {
-	_g_ := getg()
-	if !_g_.m.spinning {
-		throw("resetspinning: not a spinning m")
-	}
-	_g_.m.spinning = false
-	nmspinning := atomic.Xadd(&sched.nmspinning, -1)
-	if int32(nmspinning) < 0 {
-		throw("findrunnable: negative nmspinning")
-	}
-	// M wakeup policy is deliberately somewhat conservative, so check if we
-	// need to wakeup another P here. See "Worker thread parking/unparking"
-	// comment at the top of the file for details.
-	wakep()
-}
-
-// injectglist adds each runnable G on the list to some run queue,
-// and clears glist. If there is no current P, they are added to the
-// global queue, and up to npidle M's are started to run them.
-// Otherwise, for each idle P, this adds a G to the global queue
-// and starts an M. Any remaining G's are added to the current P's
-// local run queue.
-// This may temporarily acquire sched.lock.
-// Can run concurrently with GC.
-func injectglist(glist *gList) {
-	if glist.empty() {
-		return
-	}
-	if trace.enabled {
-		for gp := glist.head.ptr(); gp != nil; gp = gp.schedlink.ptr() {
-			traceGoUnpark(gp, 0)
-		}
-	}
-
-	// Mark all the goroutines as runnable before we put them
-	// on the run queues.
-	head := glist.head.ptr()
-	var tail *g
-	qsize := 0
-	for gp := head; gp != nil; gp = gp.schedlink.ptr() {
-		tail = gp
-		qsize++
-		casgstatus(gp, _Gwaiting, _Grunnable)
-	}
-
-	// Turn the gList into a gQueue.
-	var q gQueue
-	q.head.set(head)
-	q.tail.set(tail)
-	*glist = gList{}
-
-	startIdle := func(n int) {
-		for ; n != 0 && sched.npidle != 0; n-- {
-			startm(nil, false)
-		}
-	}
-
-	pp := getg().m.p.ptr()
-	if pp == nil {
-		lock(&sched.lock)
-		globrunqputbatch(&q, int32(qsize))
-		unlock(&sched.lock)
-		startIdle(qsize)
-		return
-	}
-
-	npidle := int(atomic.Load(&sched.npidle))
-	var globq gQueue
-	var n int
-	for n = 0; n < npidle && !q.empty(); n++ {
-		g := q.pop()
-		globq.pushBack(g)
-	}
-	if n > 0 {
-		lock(&sched.lock)
-		globrunqputbatch(&globq, int32(n))
-		unlock(&sched.lock)
-		startIdle(n)
-		qsize -= n
-	}
-
-	if !q.empty() {
-		runqputbatch(pp, &q, qsize)
-	}
-}
-
-// One round of scheduler: find a runnable goroutine and execute it.
-// Never returns.
-func schedule() {
-	_g_ := getg()
-
-	if _g_.m.locks != 0 {
-		throw("schedule: holding locks")
-	}
-
-	if _g_.m.lockedg != 0 {
-		stoplockedm()
-		execute(_g_.m.lockedg.ptr(), false) // Never returns.
-	}
-
-	// We should not schedule away from a g that is executing a cgo call,
-	// since the cgo call is using the m's g0 stack.
-	if _g_.m.incgo {
-		throw("schedule: in cgo")
-	}
-
-top:
-	pp := _g_.m.p.ptr()
-	pp.preempt = false
-
-	if sched.gcwaiting != 0 {
-		gcstopm()
-		goto top
-	}
-	if pp.runSafePointFn != 0 {
-		runSafePointFn()
-	}
-
-	// Sanity check: if we are spinning, the run queue should be empty.
-	// Check this before calling checkTimers, as that might call
-	// goready to put a ready goroutine on the local run queue.
-	if _g_.m.spinning && (pp.runnext != 0 || pp.runqhead != pp.runqtail) {
-		throw("schedule: spinning with local work")
-	}
-
-	checkTimers(pp, 0)
-
-	var gp *g
-	var inheritTime bool
-
-	// Normal goroutines will check for need to wakeP in ready,
-	// but GCworkers and tracereaders will not, so the check must
-	// be done here instead.
-	tryWakeP := false
-	if trace.enabled || trace.shutdown {
-		gp = traceReader()
-		if gp != nil {
-			casgstatus(gp, _Gwaiting, _Grunnable)
-			traceGoUnpark(gp, 0)
-			tryWakeP = true
-		}
-	}
-	if gp == nil && gcBlackenEnabled != 0 {
-		gp = gcController.findRunnableGCWorker(_g_.m.p.ptr())
-		if gp != nil {
-			tryWakeP = true
-		}
-	}
-	if gp == nil {
-		// Check the global runnable queue once in a while to ensure fairness.
-		// Otherwise two goroutines can completely occupy the local runqueue
-		// by constantly respawning each other.
-		if _g_.m.p.ptr().schedtick%61 == 0 && sched.runqsize > 0 {
-			lock(&sched.lock)
-			gp = globrunqget(_g_.m.p.ptr(), 1)
-			unlock(&sched.lock)
-		}
-	}
-	if gp == nil {
-		gp, inheritTime = runqget(_g_.m.p.ptr())
-		// We can see gp != nil here even if the M is spinning,
-		// if checkTimers added a local goroutine via goready.
-	}
-	if gp == nil {
-		gp, inheritTime = findrunnable() // blocks until work is available
-	}
-
-	// This thread is going to run a goroutine and is not spinning anymore,
-	// so if it was marked as spinning we need to reset it now and potentially
-	// start a new spinning M.
-	if _g_.m.spinning {
-		resetspinning()
-	}
-
-	if sched.disable.user && !schedEnabled(gp) {
-		// Scheduling of this goroutine is disabled. Put it on
-		// the list of pending runnable goroutines for when we
-		// re-enable user scheduling and look again.
-		lock(&sched.lock)
-		if schedEnabled(gp) {
-			// Something re-enabled scheduling while we
-			// were acquiring the lock.
-			unlock(&sched.lock)
-		} else {
-			sched.disable.runnable.pushBack(gp)
-			sched.disable.n++
-			unlock(&sched.lock)
-			goto top
-		}
-	}
-
-	// If about to schedule a not-normal goroutine (a GCworker or tracereader),
-	// wake a P if there is one.
-	if tryWakeP {
-		wakep()
-	}
-	if gp.lockedm != 0 {
-		// Hands off own p to the locked m,
-		// then blocks waiting for a new p.
-		startlockedm(gp)
-		goto top
-	}
-
-	execute(gp, inheritTime)
-}
-
-// dropg removes the association between m and the current goroutine m->curg (gp for short).
-// Typically a caller sets gp's status away from Grunning and then
-// immediately calls dropg to finish the job. The caller is also responsible
-// for arranging that gp will be restarted using ready at an
-// appropriate time. After calling dropg and arranging for gp to be
-// readied later, the caller can do other work but eventually should
-// call schedule to restart the scheduling of goroutines on this m.
-func dropg() {
-	_g_ := getg()
-
-	setMNoWB(&_g_.m.curg.m, nil)
-	setGNoWB(&_g_.m.curg, nil)
-}
-
-// checkTimers runs any timers for the P that are ready.
-// If now is not 0 it is the current time.
-// It returns the passed time or the current time if now was passed as 0.
-// and the time when the next timer should run or 0 if there is no next timer,
-// and reports whether it ran any timers.
-// If the time when the next timer should run is not 0,
-// it is always larger than the returned time.
-// We pass now in and out to avoid extra calls of nanotime.
-//go:yeswritebarrierrec
-func checkTimers(pp *p, now int64) (rnow, pollUntil int64, ran bool) {
-	// If it's not yet time for the first timer, or the first adjusted
-	// timer, then there is nothing to do.
-	next := int64(atomic.Load64(&pp.timer0When))
-	nextAdj := int64(atomic.Load64(&pp.timerModifiedEarliest))
-	if next == 0 || (nextAdj != 0 && nextAdj < next) {
-		next = nextAdj
-	}
-
-	if next == 0 {
-		// No timers to run or adjust.
-		return now, 0, false
-	}
-
-	if now == 0 {
-		now = nanotime()
-	}
-	if now < next {
-		// Next timer is not ready to run, but keep going
-		// if we would clear deleted timers.
-		// This corresponds to the condition below where
-		// we decide whether to call clearDeletedTimers.
-		if pp != getg().m.p.ptr() || int(atomic.Load(&pp.deletedTimers)) <= int(atomic.Load(&pp.numTimers)/4) {
-			return now, next, false
-		}
-	}
-
-	lock(&pp.timersLock)
-
-	if len(pp.timers) > 0 {
-		adjusttimers(pp, now)
-		for len(pp.timers) > 0 {
-			// Note that runtimer may temporarily unlock
-			// pp.timersLock.
-			if tw := runtimer(pp, now); tw != 0 {
-				if tw > 0 {
-					pollUntil = tw
-				}
-				break
-			}
-			ran = true
-		}
-	}
-
-	// If this is the local P, and there are a lot of deleted timers,
-	// clear them out. We only do this for the local P to reduce
-	// lock contention on timersLock.
-	if pp == getg().m.p.ptr() && int(atomic.Load(&pp.deletedTimers)) > len(pp.timers)/4 {
-		clearDeletedTimers(pp)
-	}
-
-	unlock(&pp.timersLock)
-
-	return now, pollUntil, ran
-}
-
-func parkunlock_c(gp *g, lock unsafe.Pointer) bool {
-	unlock((*mutex)(lock))
-	return true
-}
-
-// park continuation on g0.
-func park_m(gp *g) {
-	_g_ := getg()
-
-	if trace.enabled {
-		traceGoPark(_g_.m.waittraceev, _g_.m.waittraceskip)
-	}
-
-	casgstatus(gp, _Grunning, _Gwaiting)
-	dropg()
-
-	if fn := _g_.m.waitunlockf; fn != nil {
-		ok := fn(gp, _g_.m.waitlock)
-		_g_.m.waitunlockf = nil
-		_g_.m.waitlock = nil
-		if !ok {
-			if trace.enabled {
-				traceGoUnpark(gp, 2)
-			}
-			casgstatus(gp, _Gwaiting, _Grunnable)
-			execute(gp, true) // Schedule it back, never returns.
-		}
-	}
-	schedule()
-}
-
-func goschedImpl(gp *g) {
-	status := readgstatus(gp)
-	if status&^_Gscan != _Grunning {
-		dumpgstatus(gp)
-		throw("bad g status")
-	}
-	casgstatus(gp, _Grunning, _Grunnable)
-	dropg()
-	lock(&sched.lock)
-	globrunqput(gp)
-	unlock(&sched.lock)
-
-	schedule()
-}
-
-// Gosched continuation on g0.
-func gosched_m(gp *g) {
-	if trace.enabled {
-		traceGoSched()
-	}
-	goschedImpl(gp)
-}
-
-// goschedguarded is a forbidden-states-avoided version of gosched_m
-func goschedguarded_m(gp *g) {
-
-	if !canPreemptM(gp.m) {
-		gogo(&gp.sched) // never return
-	}
-
-	if trace.enabled {
-		traceGoSched()
-	}
-	goschedImpl(gp)
-}
-
-func gopreempt_m(gp *g) {
-	if trace.enabled {
-		traceGoPreempt()
-	}
-	goschedImpl(gp)
-}
-
-// preemptPark parks gp and puts it in _Gpreempted.
-//
-//go:systemstack
-func preemptPark(gp *g) {
-	if trace.enabled {
-		traceGoPark(traceEvGoBlock, 0)
-	}
-	status := readgstatus(gp)
-	if status&^_Gscan != _Grunning {
-		dumpgstatus(gp)
-		throw("bad g status")
-	}
-	gp.waitreason = waitReasonPreempted
-
-	if gp.asyncSafePoint {
-		// Double-check that async preemption does not
-		// happen in SPWRITE assembly functions.
-		// isAsyncSafePoint must exclude this case.
-		f := findfunc(gp.sched.pc)
-		if !f.valid() {
-			throw("preempt at unknown pc")
-		}
-		if f.flag&funcFlag_SPWRITE != 0 {
-			println("runtime: unexpected SPWRITE function", funcname(f), "in async preempt")
-			throw("preempt SPWRITE")
-		}
-	}
-
-	// Transition from _Grunning to _Gscan|_Gpreempted. We can't
-	// be in _Grunning when we dropg because then we'd be running
-	// without an M, but the moment we're in _Gpreempted,
-	// something could claim this G before we've fully cleaned it
-	// up. Hence, we set the scan bit to lock down further
-	// transitions until we can dropg.
-	casGToPreemptScan(gp, _Grunning, _Gscan|_Gpreempted)
-	dropg()
-	casfrom_Gscanstatus(gp, _Gscan|_Gpreempted, _Gpreempted)
-	schedule()
-}
-
-// goyield is like Gosched, but it:
-// - emits a GoPreempt trace event instead of a GoSched trace event
-// - puts the current G on the runq of the current P instead of the globrunq
-func goyield() {
-	checkTimeouts()
-	mcall(goyield_m)
-}
-
-func goyield_m(gp *g) {
-	if trace.enabled {
-		traceGoPreempt()
-	}
-	pp := gp.m.p.ptr()
-	casgstatus(gp, _Grunning, _Grunnable)
-	dropg()
-	runqput(pp, gp, false)
-	schedule()
-}
-
-// Finishes execution of the current goroutine.
-func goexit1() {
-	if raceenabled {
-		racegoend()
-	}
-	if trace.enabled {
-		traceGoEnd()
-	}
-	mcall(goexit0)
-}
-
-// goexit continuation on g0.
-func goexit0(gp *g) {
-	_g_ := getg()
-	_p_ := _g_.m.p.ptr()
-
-	casgstatus(gp, _Grunning, _Gdead)
-	gcController.addScannableStack(_p_, -int64(gp.stack.hi-gp.stack.lo))
-	if isSystemGoroutine(gp, false) {
-		atomic.Xadd(&sched.ngsys, -1)
-	}
-	gp.m = nil
-	locked := gp.lockedm != 0
-	gp.lockedm = 0
-	_g_.m.lockedg = 0
-	gp.preemptStop = false
-	gp.paniconfault = false
-	gp._defer = nil // should be true already but just in case.
-	gp._panic = nil // non-nil for Goexit during panic. points at stack-allocated data.
-	gp.writebuf = nil
-	gp.waitreason = 0
-	gp.param = nil
-	gp.labels = nil
-	gp.timer = nil
-
-	if gcBlackenEnabled != 0 && gp.gcAssistBytes > 0 {
-		// Flush assist credit to the global pool. This gives
-		// better information to pacing if the application is
-		// rapidly creating an exiting goroutines.
-		assistWorkPerByte := gcController.assistWorkPerByte.Load()
-		scanCredit := int64(assistWorkPerByte * float64(gp.gcAssistBytes))
-		atomic.Xaddint64(&gcController.bgScanCredit, scanCredit)
-		gp.gcAssistBytes = 0
-	}
-
-	dropg()
-
-	if GOARCH == "wasm" { // no threads yet on wasm
-		gfput(_p_, gp)
-		schedule() // never returns
-	}
-
-	if _g_.m.lockedInt != 0 {
-		print("invalid m->lockedInt = ", _g_.m.lockedInt, "\n")
-		throw("internal lockOSThread error")
-	}
-	gfput(_p_, gp)
-	if locked {
-		// The goroutine may have locked this thread because
-		// it put it in an unusual kernel state. Kill it
-		// rather than returning it to the thread pool.
-
-		// Return to mstart, which will release the P and exit
-		// the thread.
-		if GOOS != "plan9" { // See golang.org/issue/22227.
-			gogo(&_g_.m.g0.sched)
-		} else {
-			// Clear lockedExt on plan9 since we may end up re-using
-			// this thread.
-			_g_.m.lockedExt = 0
-		}
-	}
-	schedule()
-}
-
-// save updates getg().sched to refer to pc and sp so that a following
-// gogo will restore pc and sp.
-//
-// save must not have write barriers because invoking a write barrier
-// can clobber getg().sched.
-//
-//go:nosplit
-//go:nowritebarrierrec
-func save(pc, sp uintptr) {
-	_g_ := getg()
-
-	if _g_ == _g_.m.g0 || _g_ == _g_.m.gsignal {
-		// m.g0.sched is special and must describe the context
-		// for exiting the thread. mstart1 writes to it directly.
-		// m.gsignal.sched should not be used at all.
-		// This check makes sure save calls do not accidentally
-		// run in contexts where they'd write to system g's.
-		throw("save on system g not allowed")
-	}
-
-	_g_.sched.pc = pc
-	_g_.sched.sp = sp
-	_g_.sched.lr = 0
-	_g_.sched.ret = 0
-	// We need to ensure ctxt is zero, but can't have a write
-	// barrier here. However, it should always already be zero.
-	// Assert that.
-	if _g_.sched.ctxt != nil {
-		badctxt()
-	}
-}
-
-// The goroutine g is about to enter a system call.
-// Record that it's not using the cpu anymore.
-// This is called only from the go syscall library and cgocall,
-// not from the low-level system calls used by the runtime.
-//
-// Entersyscall cannot split the stack: the save must
-// make g->sched refer to the caller's stack segment, because
-// entersyscall is going to return immediately after.
-//
-// Nothing entersyscall calls can split the stack either.
-// We cannot safely move the stack during an active call to syscall,
-// because we do not know which of the uintptr arguments are
-// really pointers (back into the stack).
-// In practice, this means that we make the fast path run through
-// entersyscall doing no-split things, and the slow path has to use systemstack
-// to run bigger things on the system stack.
-//
-// reentersyscall is the entry point used by cgo callbacks, where explicitly
-// saved SP and PC are restored. This is needed when exitsyscall will be called
-// from a function further up in the call stack than the parent, as g->syscallsp
-// must always point to a valid stack frame. entersyscall below is the normal
-// entry point for syscalls, which obtains the SP and PC from the caller.
-//
-// Syscall tracing:
-// At the start of a syscall we emit traceGoSysCall to capture the stack trace.
-// If the syscall does not block, that is it, we do not emit any other events.
-// If the syscall blocks (that is, P is retaken), retaker emits traceGoSysBlock;
-// when syscall returns we emit traceGoSysExit and when the goroutine starts running
-// (potentially instantly, if exitsyscallfast returns true) we emit traceGoStart.
-// To ensure that traceGoSysExit is emitted strictly after traceGoSysBlock,
-// we remember current value of syscalltick in m (_g_.m.syscalltick = _g_.m.p.ptr().syscalltick),
-// whoever emits traceGoSysBlock increments p.syscalltick afterwards;
-// and we wait for the increment before emitting traceGoSysExit.
-// Note that the increment is done even if tracing is not enabled,
-// because tracing can be enabled in the middle of syscall. We don't want the wait to hang.
-//
-//go:nosplit
-func reentersyscall(pc, sp uintptr) {
-	_g_ := getg()
-
-	// Disable preemption because during this function g is in Gsyscall status,
-	// but can have inconsistent g->sched, do not let GC observe it.
-	_g_.m.locks++
-
-	// Entersyscall must not call any function that might split/grow the stack.
-	// (See details in comment above.)
-	// Catch calls that might, by replacing the stack guard with something that
-	// will trip any stack check and leaving a flag to tell newstack to die.
-	_g_.stackguard0 = stackPreempt
-	_g_.throwsplit = true
-
-	// Leave SP around for GC and traceback.
-	save(pc, sp)
-	_g_.syscallsp = sp
-	_g_.syscallpc = pc
-	casgstatus(_g_, _Grunning, _Gsyscall)
-	if _g_.syscallsp < _g_.stack.lo || _g_.stack.hi < _g_.syscallsp {
-		systemstack(func() {
-			print("entersyscall inconsistent ", hex(_g_.syscallsp), " [", hex(_g_.stack.lo), ",", hex(_g_.stack.hi), "]\n")
-			throw("entersyscall")
-		})
-	}
-
-	if trace.enabled {
-		systemstack(traceGoSysCall)
-		// systemstack itself clobbers g.sched.{pc,sp} and we might
-		// need them later when the G is genuinely blocked in a
-		// syscall
-		save(pc, sp)
-	}
-
-	if atomic.Load(&sched.sysmonwait) != 0 {
-		systemstack(entersyscall_sysmon)
-		save(pc, sp)
-	}
-
-	if _g_.m.p.ptr().runSafePointFn != 0 {
-		// runSafePointFn may stack split if run on this stack
-		systemstack(runSafePointFn)
-		save(pc, sp)
-	}
-
-	_g_.m.syscalltick = _g_.m.p.ptr().syscalltick
-	_g_.sysblocktraced = true
-	pp := _g_.m.p.ptr()
-	pp.m = 0
-	_g_.m.oldp.set(pp)
-	_g_.m.p = 0
-	atomic.Store(&pp.status, _Psyscall)
-	if sched.gcwaiting != 0 {
-		systemstack(entersyscall_gcwait)
-		save(pc, sp)
-	}
-
-	_g_.m.locks--
-}
-
-// Standard syscall entry used by the go syscall library and normal cgo calls.
-//
-// This is exported via linkname to assembly in the syscall package.
-//
-//go:nosplit
-//go:linkname entersyscall
-func entersyscall() {
-	reentersyscall(getcallerpc(), getcallersp())
-}
-
-func entersyscall_sysmon() {
-	lock(&sched.lock)
-	if atomic.Load(&sched.sysmonwait) != 0 {
-		atomic.Store(&sched.sysmonwait, 0)
-		notewakeup(&sched.sysmonnote)
-	}
-	unlock(&sched.lock)
-}
-
-func entersyscall_gcwait() {
-	_g_ := getg()
-	_p_ := _g_.m.oldp.ptr()
-
-	lock(&sched.lock)
-	if sched.stopwait > 0 && atomic.Cas(&_p_.status, _Psyscall, _Pgcstop) {
-		if trace.enabled {
-			traceGoSysBlock(_p_)
-			traceProcStop(_p_)
-		}
-		_p_.syscalltick++
-		if sched.stopwait--; sched.stopwait == 0 {
-			notewakeup(&sched.stopnote)
-		}
-	}
-	unlock(&sched.lock)
-}
-
-// The same as entersyscall(), but with a hint that the syscall is blocking.
-//go:nosplit
-func entersyscallblock() {
-	_g_ := getg()
-
-	_g_.m.locks++ // see comment in entersyscall
-	_g_.throwsplit = true
-	_g_.stackguard0 = stackPreempt // see comment in entersyscall
-	_g_.m.syscalltick = _g_.m.p.ptr().syscalltick
-	_g_.sysblocktraced = true
-	_g_.m.p.ptr().syscalltick++
-
-	// Leave SP around for GC and traceback.
-	pc := getcallerpc()
-	sp := getcallersp()
-	save(pc, sp)
-	_g_.syscallsp = _g_.sched.sp
-	_g_.syscallpc = _g_.sched.pc
-	if _g_.syscallsp < _g_.stack.lo || _g_.stack.hi < _g_.syscallsp {
-		sp1 := sp
-		sp2 := _g_.sched.sp
-		sp3 := _g_.syscallsp
-		systemstack(func() {
-			print("entersyscallblock inconsistent ", hex(sp1), " ", hex(sp2), " ", hex(sp3), " [", hex(_g_.stack.lo), ",", hex(_g_.stack.hi), "]\n")
-			throw("entersyscallblock")
-		})
-	}
-	casgstatus(_g_, _Grunning, _Gsyscall)
-	if _g_.syscallsp < _g_.stack.lo || _g_.stack.hi < _g_.syscallsp {
-		systemstack(func() {
-			print("entersyscallblock inconsistent ", hex(sp), " ", hex(_g_.sched.sp), " ", hex(_g_.syscallsp), " [", hex(_g_.stack.lo), ",", hex(_g_.stack.hi), "]\n")
-			throw("entersyscallblock")
-		})
-	}
-
-	systemstack(entersyscallblock_handoff)
-
-	// Resave for traceback during blocked call.
-	save(getcallerpc(), getcallersp())
-
-	_g_.m.locks--
-}
-
-func entersyscallblock_handoff() {
-	if trace.enabled {
-		traceGoSysCall()
-		traceGoSysBlock(getg().m.p.ptr())
-	}
-	handoffp(releasep())
-}
-
-// The goroutine g exited its system call.
-// Arrange for it to run on a cpu again.
-// This is called only from the go syscall library, not
-// from the low-level system calls used by the runtime.
-//
-// Write barriers are not allowed because our P may have been stolen.
-//
-// This is exported via linkname to assembly in the syscall package.
-//
-//go:nosplit
-//go:nowritebarrierrec
-//go:linkname exitsyscall
-func exitsyscall() {
-	_g_ := getg()
-
-	_g_.m.locks++ // see comment in entersyscall
-	if getcallersp() > _g_.syscallsp {
-		throw("exitsyscall: syscall frame is no longer valid")
-	}
-
-	_g_.waitsince = 0
-	oldp := _g_.m.oldp.ptr()
-	_g_.m.oldp = 0
-	if exitsyscallfast(oldp) {
-		if trace.enabled {
-			if oldp != _g_.m.p.ptr() || _g_.m.syscalltick != _g_.m.p.ptr().syscalltick {
-				systemstack(traceGoStart)
-			}
-		}
-		// There's a cpu for us, so we can run.
-		_g_.m.p.ptr().syscalltick++
-		// We need to cas the status and scan before resuming...
-		casgstatus(_g_, _Gsyscall, _Grunning)
-
-		// Garbage collector isn't running (since we are),
-		// so okay to clear syscallsp.
-		_g_.syscallsp = 0
-		_g_.m.locks--
-		if _g_.preempt {
-			// restore the preemption request in case we've cleared it in newstack
-			_g_.stackguard0 = stackPreempt
-		} else {
-			// otherwise restore the real _StackGuard, we've spoiled it in entersyscall/entersyscallblock
-			_g_.stackguard0 = _g_.stack.lo + _StackGuard
-		}
-		_g_.throwsplit = false
-
-		if sched.disable.user && !schedEnabled(_g_) {
-			// Scheduling of this goroutine is disabled.
-			Gosched()
-		}
-
-		return
-	}
-
-	_g_.sysexitticks = 0
-	if trace.enabled {
-		// Wait till traceGoSysBlock event is emitted.
-		// This ensures consistency of the trace (the goroutine is started after it is blocked).
-		for oldp != nil && oldp.syscalltick == _g_.m.syscalltick {
-			osyield()
-		}
-		// We can't trace syscall exit right now because we don't have a P.
-		// Tracing code can invoke write barriers that cannot run without a P.
-		// So instead we remember the syscall exit time and emit the event
-		// in execute when we have a P.
-		_g_.sysexitticks = cputicks()
-	}
-
-	_g_.m.locks--
-
-	// Call the scheduler.
-	mcall(exitsyscall0)
-
-	// Scheduler returned, so we're allowed to run now.
-	// Delete the syscallsp information that we left for
-	// the garbage collector during the system call.
-	// Must wait until now because until gosched returns
-	// we don't know for sure that the garbage collector
-	// is not running.
-	_g_.syscallsp = 0
-	_g_.m.p.ptr().syscalltick++
-	_g_.throwsplit = false
-}
-
-//go:nosplit
-func exitsyscallfast(oldp *p) bool {
-	_g_ := getg()
-
-	// Freezetheworld sets stopwait but does not retake P's.
-	if sched.stopwait == freezeStopWait {
-		return false
-	}
-
-	// Try to re-acquire the last P.
-	if oldp != nil && oldp.status == _Psyscall && atomic.Cas(&oldp.status, _Psyscall, _Pidle) {
-		// There's a cpu for us, so we can run.
-		wirep(oldp)
-		exitsyscallfast_reacquired()
-		return true
-	}
-
-	// Try to get any other idle P.
-	if sched.pidle != 0 {
-		var ok bool
-		systemstack(func() {
-			ok = exitsyscallfast_pidle()
-			if ok && trace.enabled {
-				if oldp != nil {
-					// Wait till traceGoSysBlock event is emitted.
-					// This ensures consistency of the trace (the goroutine is started after it is blocked).
-					for oldp.syscalltick == _g_.m.syscalltick {
-						osyield()
-					}
-				}
-				traceGoSysExit(0)
-			}
-		})
-		if ok {
-			return true
-		}
-	}
-	return false
-}
-
-// exitsyscallfast_reacquired is the exitsyscall path on which this G
-// has successfully reacquired the P it was running on before the
-// syscall.
-//
-//go:nosplit
-func exitsyscallfast_reacquired() {
-	_g_ := getg()
-	if _g_.m.syscalltick != _g_.m.p.ptr().syscalltick {
-		if trace.enabled {
-			// The p was retaken and then enter into syscall again (since _g_.m.syscalltick has changed).
-			// traceGoSysBlock for this syscall was already emitted,
-			// but here we effectively retake the p from the new syscall running on the same p.
-			systemstack(func() {
-				// Denote blocking of the new syscall.
-				traceGoSysBlock(_g_.m.p.ptr())
-				// Denote completion of the current syscall.
-				traceGoSysExit(0)
-			})
-		}
-		_g_.m.p.ptr().syscalltick++
-	}
-}
-
-func exitsyscallfast_pidle() bool {
-	lock(&sched.lock)
-	_p_ := pidleget()
-	if _p_ != nil && atomic.Load(&sched.sysmonwait) != 0 {
-		atomic.Store(&sched.sysmonwait, 0)
-		notewakeup(&sched.sysmonnote)
-	}
-	unlock(&sched.lock)
-	if _p_ != nil {
-		acquirep(_p_)
-		return true
-	}
-	return false
-}
-
-// exitsyscall slow path on g0.
-// Failed to acquire P, enqueue gp as runnable.
-//
-// Called via mcall, so gp is the calling g from this M.
-//
-//go:nowritebarrierrec
-func exitsyscall0(gp *g) {
-	casgstatus(gp, _Gsyscall, _Grunnable)
-	dropg()
-	lock(&sched.lock)
-	var _p_ *p
-	if schedEnabled(gp) {
-		_p_ = pidleget()
-	}
-	var locked bool
-	if _p_ == nil {
-		globrunqput(gp)
-
-		// Below, we stoplockedm if gp is locked. globrunqput releases
-		// ownership of gp, so we must check if gp is locked prior to
-		// committing the release by unlocking sched.lock, otherwise we
-		// could race with another M transitioning gp from unlocked to
-		// locked.
-		locked = gp.lockedm != 0
-	} else if atomic.Load(&sched.sysmonwait) != 0 {
-		atomic.Store(&sched.sysmonwait, 0)
-		notewakeup(&sched.sysmonnote)
-	}
-	unlock(&sched.lock)
-	if _p_ != nil {
-		acquirep(_p_)
-		execute(gp, false) // Never returns.
-	}
-	if locked {
-		// Wait until another thread schedules gp and so m again.
-		//
-		// N.B. lockedm must be this M, as this g was running on this M
-		// before entersyscall.
-		stoplockedm()
-		execute(gp, false) // Never returns.
-	}
-	stopm()
-	schedule() // Never returns.
-}
-
-// Called from syscall package before fork.
-//go:linkname syscall_runtime_BeforeFork syscall.runtime_BeforeFork
-//go:nosplit
-func syscall_runtime_BeforeFork() {
-	gp := getg().m.curg
-
-	// Block signals during a fork, so that the child does not run
-	// a signal handler before exec if a signal is sent to the process
-	// group. See issue #18600.
-	gp.m.locks++
-	sigsave(&gp.m.sigmask)
-	sigblock(false)
-
-	// This function is called before fork in syscall package.
-	// Code between fork and exec must not allocate memory nor even try to grow stack.
-	// Here we spoil g->_StackGuard to reliably detect any attempts to grow stack.
-	// runtime_AfterFork will undo this in parent process, but not in child.
-	gp.stackguard0 = stackFork
-}
-
-// Called from syscall package after fork in parent.
-//go:linkname syscall_runtime_AfterFork syscall.runtime_AfterFork
-//go:nosplit
-func syscall_runtime_AfterFork() {
-	gp := getg().m.curg
-
-	// See the comments in beforefork.
-	gp.stackguard0 = gp.stack.lo + _StackGuard
-
-	msigrestore(gp.m.sigmask)
-
-	gp.m.locks--
-}
-
-// inForkedChild is true while manipulating signals in the child process.
-// This is used to avoid calling libc functions in case we are using vfork.
-var inForkedChild bool
-
-// Called from syscall package after fork in child.
-// It resets non-sigignored signals to the default handler, and
-// restores the signal mask in preparation for the exec.
-//
-// Because this might be called during a vfork, and therefore may be
-// temporarily sharing address space with the parent process, this must
-// not change any global variables or calling into C code that may do so.
-//
-//go:linkname syscall_runtime_AfterForkInChild syscall.runtime_AfterForkInChild
-//go:nosplit
-//go:nowritebarrierrec
-func syscall_runtime_AfterForkInChild() {
-	// It's OK to change the global variable inForkedChild here
-	// because we are going to change it back. There is no race here,
-	// because if we are sharing address space with the parent process,
-	// then the parent process can not be running concurrently.
-	inForkedChild = true
-
-	clearSignalHandlers()
-
-	// When we are the child we are the only thread running,
-	// so we know that nothing else has changed gp.m.sigmask.
-	msigrestore(getg().m.sigmask)
-
-	inForkedChild = false
-}
-
-// pendingPreemptSignals is the number of preemption signals
-// that have been sent but not received. This is only used on Darwin.
-// For #41702.
-var pendingPreemptSignals uint32
-
-// Called from syscall package before Exec.
-//go:linkname syscall_runtime_BeforeExec syscall.runtime_BeforeExec
-func syscall_runtime_BeforeExec() {
-	// Prevent thread creation during exec.
-	execLock.lock()
-
-	// On Darwin, wait for all pending preemption signals to
-	// be received. See issue #41702.
-	if GOOS == "darwin" || GOOS == "ios" {
-		for int32(atomic.Load(&pendingPreemptSignals)) > 0 {
-			osyield()
-		}
-	}
-}
-
-// Called from syscall package after Exec.
-//go:linkname syscall_runtime_AfterExec syscall.runtime_AfterExec
-func syscall_runtime_AfterExec() {
-	execLock.unlock()
-}
-
-// Allocate a new g, with a stack big enough for stacksize bytes.
-func malg(stacksize int32) *g {
-	newg := new(g)
-	if stacksize >= 0 {
-		stacksize = round2(_StackSystem + stacksize)
-		systemstack(func() {
-			newg.stack = stackalloc(uint32(stacksize))
-		})
-		newg.stackguard0 = newg.stack.lo + _StackGuard
-		newg.stackguard1 = ^uintptr(0)
-		// Clear the bottom word of the stack. We record g
-		// there on gsignal stack during VDSO on ARM and ARM64.
-		*(*uintptr)(unsafe.Pointer(newg.stack.lo)) = 0
-	}
-	return newg
-}
-
-// Create a new g running fn.
-// Put it on the queue of g's waiting to run.
-// The compiler turns a go statement into a call to this.
-func newproc(fn *funcval) {
-	gp := getg()
-	pc := getcallerpc()
-	systemstack(func() {
-		newg := newproc1(fn, gp, pc)
-
-		_p_ := getg().m.p.ptr()
-		runqput(_p_, newg, true)
-
-		if mainStarted {
-			wakep()
-		}
-	})
-}
-
-// Create a new g in state _Grunnable, starting at fn. callerpc is the
-// address of the go statement that created this. The caller is responsible
-// for adding the new g to the scheduler.
-func newproc1(fn *funcval, callergp *g, callerpc uintptr) *g {
-	_g_ := getg()
-
-	if fn == nil {
-		_g_.m.throwing = -1 // do not dump full stacks
-		throw("go of nil func value")
-	}
-	acquirem() // disable preemption because it can be holding p in a local var
-
-	_p_ := _g_.m.p.ptr()
-	newg := gfget(_p_)
-	if newg == nil {
-		newg = malg(_StackMin)
-		casgstatus(newg, _Gidle, _Gdead)
-		allgadd(newg) // publishes with a g->status of Gdead so GC scanner doesn't look at uninitialized stack.
-	}
-	if newg.stack.hi == 0 {
-		throw("newproc1: newg missing stack")
-	}
-
-	if readgstatus(newg) != _Gdead {
-		throw("newproc1: new g is not Gdead")
-	}
-
-	totalSize := uintptr(4*goarch.PtrSize + sys.MinFrameSize) // extra space in case of reads slightly beyond frame
-	totalSize = alignUp(totalSize, sys.StackAlign)
-	sp := newg.stack.hi - totalSize
-	spArg := sp
-	if usesLR {
-		// caller's LR
-		*(*uintptr)(unsafe.Pointer(sp)) = 0
-		prepGoExitFrame(sp)
-		spArg += sys.MinFrameSize
-	}
-
-	memclrNoHeapPointers(unsafe.Pointer(&newg.sched), unsafe.Sizeof(newg.sched))
-	newg.sched.sp = sp
-	newg.stktopsp = sp
-	newg.sched.pc = abi.FuncPCABI0(goexit) + sys.PCQuantum // +PCQuantum so that previous instruction is in same function
-	newg.sched.g = guintptr(unsafe.Pointer(newg))
-	gostartcallfn(&newg.sched, fn)
-	newg.gopc = callerpc
-	newg.ancestors = saveAncestors(callergp)
-	newg.startpc = fn.fn
-	if isSystemGoroutine(newg, false) {
-		atomic.Xadd(&sched.ngsys, +1)
-	} else {
-		// Only user goroutines inherit pprof labels.
-		if _g_.m.curg != nil {
-			newg.labels = _g_.m.curg.labels
-		}
-	}
-	// Track initial transition?
-	newg.trackingSeq = uint8(fastrand())
-	if newg.trackingSeq%gTrackingPeriod == 0 {
-		newg.tracking = true
-	}
-	casgstatus(newg, _Gdead, _Grunnable)
-	gcController.addScannableStack(_p_, int64(newg.stack.hi-newg.stack.lo))
-
-	if _p_.goidcache == _p_.goidcacheend {
-		// Sched.goidgen is the last allocated id,
-		// this batch must be [sched.goidgen+1, sched.goidgen+GoidCacheBatch].
-		// At startup sched.goidgen=0, so main goroutine receives goid=1.
-		_p_.goidcache = atomic.Xadd64(&sched.goidgen, _GoidCacheBatch)
-		_p_.goidcache -= _GoidCacheBatch - 1
-		_p_.goidcacheend = _p_.goidcache + _GoidCacheBatch
-	}
-	newg.goid = int64(_p_.goidcache)
-	_p_.goidcache++
-	if raceenabled {
-		newg.racectx = racegostart(callerpc)
-	}
-	if trace.enabled {
-		traceGoCreate(newg, newg.startpc)
-	}
-	releasem(_g_.m)
-
-	return newg
-}
-
-// saveAncestors copies previous ancestors of the given caller g and
-// includes infor for the current caller into a new set of tracebacks for
-// a g being created.
-func saveAncestors(callergp *g) *[]ancestorInfo {
-	// Copy all prior info, except for the root goroutine (goid 0).
-	if debug.tracebackancestors <= 0 || callergp.goid == 0 {
-		return nil
-	}
-	var callerAncestors []ancestorInfo
-	if callergp.ancestors != nil {
-		callerAncestors = *callergp.ancestors
-	}
-	n := int32(len(callerAncestors)) + 1
-	if n > debug.tracebackancestors {
-		n = debug.tracebackancestors
-	}
-	ancestors := make([]ancestorInfo, n)
-	copy(ancestors[1:], callerAncestors)
-
-	var pcs [_TracebackMaxFrames]uintptr
-	npcs := gcallers(callergp, 0, pcs[:])
-	ipcs := make([]uintptr, npcs)
-	copy(ipcs, pcs[:])
-	ancestors[0] = ancestorInfo{
-		pcs:  ipcs,
-		goid: callergp.goid,
-		gopc: callergp.gopc,
-	}
-
-	ancestorsp := new([]ancestorInfo)
-	*ancestorsp = ancestors
-	return ancestorsp
-}
-
-// Put on gfree list.
-// If local list is too long, transfer a batch to the global list.
-func gfput(_p_ *p, gp *g) {
-	if readgstatus(gp) != _Gdead {
-		throw("gfput: bad status (not Gdead)")
-	}
-
-	stksize := gp.stack.hi - gp.stack.lo
-
-	if stksize != _FixedStack {
-		// non-standard stack size - free it.
-		stackfree(gp.stack)
-		gp.stack.lo = 0
-		gp.stack.hi = 0
-		gp.stackguard0 = 0
-	}
-
-	_p_.gFree.push(gp)
-	_p_.gFree.n++
-	if _p_.gFree.n >= 64 {
-		var (
-			inc      int32
-			stackQ   gQueue
-			noStackQ gQueue
-		)
-		for _p_.gFree.n >= 32 {
-			gp = _p_.gFree.pop()
-			_p_.gFree.n--
-			if gp.stack.lo == 0 {
-				noStackQ.push(gp)
-			} else {
-				stackQ.push(gp)
-			}
-			inc++
-		}
-		lock(&sched.gFree.lock)
-		sched.gFree.noStack.pushAll(noStackQ)
-		sched.gFree.stack.pushAll(stackQ)
-		sched.gFree.n += inc
-		unlock(&sched.gFree.lock)
-	}
-}
-
-// Get from gfree list.
-// If local list is empty, grab a batch from global list.
-func gfget(_p_ *p) *g {
-retry:
-	if _p_.gFree.empty() && (!sched.gFree.stack.empty() || !sched.gFree.noStack.empty()) {
-		lock(&sched.gFree.lock)
-		// Move a batch of free Gs to the P.
-		for _p_.gFree.n < 32 {
-			// Prefer Gs with stacks.
-			gp := sched.gFree.stack.pop()
-			if gp == nil {
-				gp = sched.gFree.noStack.pop()
-				if gp == nil {
-					break
-				}
-			}
-			sched.gFree.n--
-			_p_.gFree.push(gp)
-			_p_.gFree.n++
-		}
-		unlock(&sched.gFree.lock)
-		goto retry
-	}
-	gp := _p_.gFree.pop()
-	if gp == nil {
-		return nil
-	}
-	_p_.gFree.n--
-	if gp.stack.lo == 0 {
-		// Stack was deallocated in gfput. Allocate a new one.
-		systemstack(func() {
-			gp.stack = stackalloc(_FixedStack)
-		})
-		gp.stackguard0 = gp.stack.lo + _StackGuard
-	} else {
-		if raceenabled {
-			racemalloc(unsafe.Pointer(gp.stack.lo), gp.stack.hi-gp.stack.lo)
-		}
-		if msanenabled {
-			msanmalloc(unsafe.Pointer(gp.stack.lo), gp.stack.hi-gp.stack.lo)
-		}
-		if asanenabled {
-			asanunpoison(unsafe.Pointer(gp.stack.lo), gp.stack.hi-gp.stack.lo)
-		}
-	}
-	return gp
-}
-
-// Purge all cached G's from gfree list to the global list.
-func gfpurge(_p_ *p) {
-	var (
-		inc      int32
-		stackQ   gQueue
-		noStackQ gQueue
-	)
-	for !_p_.gFree.empty() {
-		gp := _p_.gFree.pop()
-		_p_.gFree.n--
-		if gp.stack.lo == 0 {
-			noStackQ.push(gp)
-		} else {
-			stackQ.push(gp)
-		}
-		inc++
-	}
-	lock(&sched.gFree.lock)
-	sched.gFree.noStack.pushAll(noStackQ)
-	sched.gFree.stack.pushAll(stackQ)
-	sched.gFree.n += inc
-	unlock(&sched.gFree.lock)
-}
-
-// Breakpoint executes a breakpoint trap.
-func Breakpoint() {
-	breakpoint()
-}
-
-// dolockOSThread is called by LockOSThread and lockOSThread below
-// after they modify m.locked. Do not allow preemption during this call,
-// or else the m might be different in this function than in the caller.
-//go:nosplit
-func dolockOSThread() {
-	if GOARCH == "wasm" {
-		return // no threads on wasm yet
-	}
-	_g_ := getg()
-	_g_.m.lockedg.set(_g_)
-	_g_.lockedm.set(_g_.m)
-}
-
-//go:nosplit
-
-// LockOSThread wires the calling goroutine to its current operating system thread.
-// The calling goroutine will always execute in that thread,
-// and no other goroutine will execute in it,
-// until the calling goroutine has made as many calls to
-// UnlockOSThread as to LockOSThread.
-// If the calling goroutine exits without unlocking the thread,
-// the thread will be terminated.
-//
-// All init functions are run on the startup thread. Calling LockOSThread
-// from an init function will cause the main function to be invoked on
-// that thread.
-//
-// A goroutine should call LockOSThread before calling OS services or
-// non-Go library functions that depend on per-thread state.
-func LockOSThread() {
-	if atomic.Load(&newmHandoff.haveTemplateThread) == 0 && GOOS != "plan9" {
-		// If we need to start a new thread from the locked
-		// thread, we need the template thread. Start it now
-		// while we're in a known-good state.
-		startTemplateThread()
-	}
-	_g_ := getg()
-	_g_.m.lockedExt++
-	if _g_.m.lockedExt == 0 {
-		_g_.m.lockedExt--
-		panic("LockOSThread nesting overflow")
-	}
-	dolockOSThread()
-}
-
-//go:nosplit
-func lockOSThread() {
-	getg().m.lockedInt++
-	dolockOSThread()
-}
-
-// dounlockOSThread is called by UnlockOSThread and unlockOSThread below
-// after they update m->locked. Do not allow preemption during this call,
-// or else the m might be in different in this function than in the caller.
-//go:nosplit
-func dounlockOSThread() {
-	if GOARCH == "wasm" {
-		return // no threads on wasm yet
-	}
-	_g_ := getg()
-	if _g_.m.lockedInt != 0 || _g_.m.lockedExt != 0 {
-		return
-	}
-	_g_.m.lockedg = 0
-	_g_.lockedm = 0
-}
-
-//go:nosplit
-
-// UnlockOSThread undoes an earlier call to LockOSThread.
-// If this drops the number of active LockOSThread calls on the
-// calling goroutine to zero, it unwires the calling goroutine from
-// its fixed operating system thread.
-// If there are no active LockOSThread calls, this is a no-op.
-//
-// Before calling UnlockOSThread, the caller must ensure that the OS
-// thread is suitable for running other goroutines. If the caller made
-// any permanent changes to the state of the thread that would affect
-// other goroutines, it should not call this function and thus leave
-// the goroutine locked to the OS thread until the goroutine (and
-// hence the thread) exits.
-func UnlockOSThread() {
-	_g_ := getg()
-	if _g_.m.lockedExt == 0 {
-		return
-	}
-	_g_.m.lockedExt--
-	dounlockOSThread()
-}
-
-//go:nosplit
-func unlockOSThread() {
-	_g_ := getg()
-	if _g_.m.lockedInt == 0 {
-		systemstack(badunlockosthread)
-	}
-	_g_.m.lockedInt--
-	dounlockOSThread()
-}
-
-func badunlockosthread() {
-	throw("runtime: internal error: misuse of lockOSThread/unlockOSThread")
-}
-
-func gcount() int32 {
-	n := int32(atomic.Loaduintptr(&allglen)) - sched.gFree.n - int32(atomic.Load(&sched.ngsys))
-	for _, _p_ := range allp {
-		n -= _p_.gFree.n
-	}
-
-	// All these variables can be changed concurrently, so the result can be inconsistent.
-	// But at least the current goroutine is running.
-	if n < 1 {
-		n = 1
-	}
-	return n
-}
-
-func mcount() int32 {
-	return int32(sched.mnext - sched.nmfreed)
-}
-
-var prof struct {
-	signalLock uint32
-	hz         int32
-}
-
-func _System()                    { _System() }
-func _ExternalCode()              { _ExternalCode() }
-func _LostExternalCode()          { _LostExternalCode() }
-func _GC()                        { _GC() }
-func _LostSIGPROFDuringAtomic64() { _LostSIGPROFDuringAtomic64() }
-func _VDSO()                      { _VDSO() }
-
-// Called if we receive a SIGPROF signal.
-// Called by the signal handler, may run during STW.
-//go:nowritebarrierrec
-func sigprof(pc, sp, lr uintptr, gp *g, mp *m) {
-	if prof.hz == 0 {
-		return
-	}
-
-	// If mp.profilehz is 0, then profiling is not enabled for this thread.
-	// We must check this to avoid a deadlock between setcpuprofilerate
-	// and the call to cpuprof.add, below.
-	if mp != nil && mp.profilehz == 0 {
-		return
-	}
-
-	// On mips{,le}/arm, 64bit atomics are emulated with spinlocks, in
-	// runtime/internal/atomic. If SIGPROF arrives while the program is inside
-	// the critical section, it creates a deadlock (when writing the sample).
-	// As a workaround, create a counter of SIGPROFs while in critical section
-	// to store the count, and pass it to sigprof.add() later when SIGPROF is
-	// received from somewhere else (with _LostSIGPROFDuringAtomic64 as pc).
-	if GOARCH == "mips" || GOARCH == "mipsle" || GOARCH == "arm" {
-		if f := findfunc(pc); f.valid() {
-			if hasPrefix(funcname(f), "runtime/internal/atomic") {
-				cpuprof.lostAtomic++
-				return
-			}
-		}
-		if GOARCH == "arm" && goarm < 7 && GOOS == "linux" && pc&0xffff0000 == 0xffff0000 {
-			// runtime/internal/atomic functions call into kernel
-			// helpers on arm < 7. See
-			// runtime/internal/atomic/sys_linux_arm.s.
-			cpuprof.lostAtomic++
-			return
-		}
-	}
-
-	// Profiling runs concurrently with GC, so it must not allocate.
-	// Set a trap in case the code does allocate.
-	// Note that on windows, one thread takes profiles of all the
-	// other threads, so mp is usually not getg().m.
-	// In fact mp may not even be stopped.
-	// See golang.org/issue/17165.
-	getg().m.mallocing++
-
-	var stk [maxCPUProfStack]uintptr
-	n := 0
-	if mp.ncgo > 0 && mp.curg != nil && mp.curg.syscallpc != 0 && mp.curg.syscallsp != 0 {
-		cgoOff := 0
-		// Check cgoCallersUse to make sure that we are not
-		// interrupting other code that is fiddling with
-		// cgoCallers.  We are running in a signal handler
-		// with all signals blocked, so we don't have to worry
-		// about any other code interrupting us.
-		if atomic.Load(&mp.cgoCallersUse) == 0 && mp.cgoCallers != nil && mp.cgoCallers[0] != 0 {
-			for cgoOff < len(mp.cgoCallers) && mp.cgoCallers[cgoOff] != 0 {
-				cgoOff++
-			}
-			copy(stk[:], mp.cgoCallers[:cgoOff])
-			mp.cgoCallers[0] = 0
-		}
-
-		// Collect Go stack that leads to the cgo call.
-		n = gentraceback(mp.curg.syscallpc, mp.curg.syscallsp, 0, mp.curg, 0, &stk[cgoOff], len(stk)-cgoOff, nil, nil, 0)
-		if n > 0 {
-			n += cgoOff
-		}
-	} else {
-		n = gentraceback(pc, sp, lr, gp, 0, &stk[0], len(stk), nil, nil, _TraceTrap|_TraceJumpStack)
-	}
-
-	if n <= 0 {
-		// Normal traceback is impossible or has failed.
-		// See if it falls into several common cases.
-		n = 0
-		if usesLibcall() && mp.libcallg != 0 && mp.libcallpc != 0 && mp.libcallsp != 0 {
-			// Libcall, i.e. runtime syscall on windows.
-			// Collect Go stack that leads to the call.
-			n = gentraceback(mp.libcallpc, mp.libcallsp, 0, mp.libcallg.ptr(), 0, &stk[0], len(stk), nil, nil, 0)
-		}
-		if n == 0 && mp != nil && mp.vdsoSP != 0 {
-			n = gentraceback(mp.vdsoPC, mp.vdsoSP, 0, gp, 0, &stk[0], len(stk), nil, nil, _TraceTrap|_TraceJumpStack)
-		}
-		if n == 0 {
-			// If all of the above has failed, account it against abstract "System" or "GC".
-			n = 2
-			if inVDSOPage(pc) {
-				pc = abi.FuncPCABIInternal(_VDSO) + sys.PCQuantum
-			} else if pc > firstmoduledata.etext {
-				// "ExternalCode" is better than "etext".
-				pc = abi.FuncPCABIInternal(_ExternalCode) + sys.PCQuantum
-			}
-			stk[0] = pc
-			if mp.preemptoff != "" {
-				stk[1] = abi.FuncPCABIInternal(_GC) + sys.PCQuantum
-			} else {
-				stk[1] = abi.FuncPCABIInternal(_System) + sys.PCQuantum
-			}
-		}
-	}
-
-	if prof.hz != 0 {
-		// Note: it can happen on Windows that we interrupted a system thread
-		// with no g, so gp could nil. The other nil checks are done out of
-		// caution, but not expected to be nil in practice.
-		var tagPtr *unsafe.Pointer
-		if gp != nil && gp.m != nil && gp.m.curg != nil {
-			tagPtr = &gp.m.curg.labels
-		}
-		cpuprof.add(tagPtr, stk[:n])
-	}
-	getg().m.mallocing--
-}
-
-// setcpuprofilerate sets the CPU profiling rate to hz times per second.
-// If hz <= 0, setcpuprofilerate turns off CPU profiling.
-func setcpuprofilerate(hz int32) {
-	// Force sane arguments.
-	if hz < 0 {
-		hz = 0
-	}
-
-	// Disable preemption, otherwise we can be rescheduled to another thread
-	// that has profiling enabled.
-	_g_ := getg()
-	_g_.m.locks++
-
-	// Stop profiler on this thread so that it is safe to lock prof.
-	// if a profiling signal came in while we had prof locked,
-	// it would deadlock.
-	setThreadCPUProfiler(0)
-
-	for !atomic.Cas(&prof.signalLock, 0, 1) {
-		osyield()
-	}
-	if prof.hz != hz {
-		setProcessCPUProfiler(hz)
-		prof.hz = hz
-	}
-	atomic.Store(&prof.signalLock, 0)
-
-	lock(&sched.lock)
-	sched.profilehz = hz
-	unlock(&sched.lock)
-
-	if hz != 0 {
-		setThreadCPUProfiler(hz)
-	}
-
-	_g_.m.locks--
-}
-
-// init initializes pp, which may be a freshly allocated p or a
-// previously destroyed p, and transitions it to status _Pgcstop.
-func (pp *p) init(id int32) {
-	pp.id = id
-	pp.status = _Pgcstop
-	pp.sudogcache = pp.sudogbuf[:0]
-	pp.deferpool = pp.deferpoolbuf[:0]
-	pp.wbBuf.reset()
-	if pp.mcache == nil {
-		if id == 0 {
-			if mcache0 == nil {
-				throw("missing mcache?")
-			}
-			// Use the bootstrap mcache0. Only one P will get
-			// mcache0: the one with ID 0.
-			pp.mcache = mcache0
-		} else {
-			pp.mcache = allocmcache()
-		}
-	}
-	if raceenabled && pp.raceprocctx == 0 {
-		if id == 0 {
-			pp.raceprocctx = raceprocctx0
-			raceprocctx0 = 0 // bootstrap
-		} else {
-			pp.raceprocctx = raceproccreate()
-		}
-	}
-	lockInit(&pp.timersLock, lockRankTimers)
-
-	// This P may get timers when it starts running. Set the mask here
-	// since the P may not go through pidleget (notably P 0 on startup).
-	timerpMask.set(id)
-	// Similarly, we may not go through pidleget before this P starts
-	// running if it is P 0 on startup.
-	idlepMask.clear(id)
-}
-
-// destroy releases all of the resources associated with pp and
-// transitions it to status _Pdead.
-//
-// sched.lock must be held and the world must be stopped.
-func (pp *p) destroy() {
-	assertLockHeld(&sched.lock)
-	assertWorldStopped()
-
-	// Move all runnable goroutines to the global queue
-	for pp.runqhead != pp.runqtail {
-		// Pop from tail of local queue
-		pp.runqtail--
-		gp := pp.runq[pp.runqtail%uint32(len(pp.runq))].ptr()
-		// Push onto head of global queue
-		globrunqputhead(gp)
-	}
-	if pp.runnext != 0 {
-		globrunqputhead(pp.runnext.ptr())
-		pp.runnext = 0
-	}
-	if len(pp.timers) > 0 {
-		plocal := getg().m.p.ptr()
-		// The world is stopped, but we acquire timersLock to
-		// protect against sysmon calling timeSleepUntil.
-		// This is the only case where we hold the timersLock of
-		// more than one P, so there are no deadlock concerns.
-		lock(&plocal.timersLock)
-		lock(&pp.timersLock)
-		moveTimers(plocal, pp.timers)
-		pp.timers = nil
-		pp.numTimers = 0
-		pp.deletedTimers = 0
-		atomic.Store64(&pp.timer0When, 0)
-		unlock(&pp.timersLock)
-		unlock(&plocal.timersLock)
-	}
-	// Flush p's write barrier buffer.
-	if gcphase != _GCoff {
-		wbBufFlush1(pp)
-		pp.gcw.dispose()
-	}
-	for i := range pp.sudogbuf {
-		pp.sudogbuf[i] = nil
-	}
-	pp.sudogcache = pp.sudogbuf[:0]
-	for j := range pp.deferpoolbuf {
-		pp.deferpoolbuf[j] = nil
-	}
-	pp.deferpool = pp.deferpoolbuf[:0]
-	systemstack(func() {
-		for i := 0; i < pp.mspancache.len; i++ {
-			// Safe to call since the world is stopped.
-			mheap_.spanalloc.free(unsafe.Pointer(pp.mspancache.buf[i]))
-		}
-		pp.mspancache.len = 0
-		lock(&mheap_.lock)
-		pp.pcache.flush(&mheap_.pages)
-		unlock(&mheap_.lock)
-	})
-	freemcache(pp.mcache)
-	pp.mcache = nil
-	gfpurge(pp)
-	traceProcFree(pp)
-	if raceenabled {
-		if pp.timerRaceCtx != 0 {
-			// The race detector code uses a callback to fetch
-			// the proc context, so arrange for that callback
-			// to see the right thing.
-			// This hack only works because we are the only
-			// thread running.
-			mp := getg().m
-			phold := mp.p.ptr()
-			mp.p.set(pp)
-
-			racectxend(pp.timerRaceCtx)
-			pp.timerRaceCtx = 0
-
-			mp.p.set(phold)
-		}
-		raceprocdestroy(pp.raceprocctx)
-		pp.raceprocctx = 0
-	}
-	pp.gcAssistTime = 0
-	pp.status = _Pdead
-}
-
-// Change number of processors.
-//
-// sched.lock must be held, and the world must be stopped.
-//
-// gcworkbufs must not be being modified by either the GC or the write barrier
-// code, so the GC must not be running if the number of Ps actually changes.
-//
-// Returns list of Ps with local work, they need to be scheduled by the caller.
-func procresize(nprocs int32) *p {
-	assertLockHeld(&sched.lock)
-	assertWorldStopped()
-
-	old := gomaxprocs
-	if old < 0 || nprocs <= 0 {
-		throw("procresize: invalid arg")
-	}
-	if trace.enabled {
-		traceGomaxprocs(nprocs)
-	}
-
-	// update statistics
-	now := nanotime()
-	if sched.procresizetime != 0 {
-		sched.totaltime += int64(old) * (now - sched.procresizetime)
-	}
-	sched.procresizetime = now
-
-	maskWords := (nprocs + 31) / 32
-
-	// Grow allp if necessary.
-	if nprocs > int32(len(allp)) {
-		// Synchronize with retake, which could be running
-		// concurrently since it doesn't run on a P.
-		lock(&allpLock)
-		if nprocs <= int32(cap(allp)) {
-			allp = allp[:nprocs]
-		} else {
-			nallp := make([]*p, nprocs)
-			// Copy everything up to allp's cap so we
-			// never lose old allocated Ps.
-			copy(nallp, allp[:cap(allp)])
-			allp = nallp
-		}
-
-		if maskWords <= int32(cap(idlepMask)) {
-			idlepMask = idlepMask[:maskWords]
-			timerpMask = timerpMask[:maskWords]
-		} else {
-			nidlepMask := make([]uint32, maskWords)
-			// No need to copy beyond len, old Ps are irrelevant.
-			copy(nidlepMask, idlepMask)
-			idlepMask = nidlepMask
-
-			ntimerpMask := make([]uint32, maskWords)
-			copy(ntimerpMask, timerpMask)
-			timerpMask = ntimerpMask
-		}
-		unlock(&allpLock)
-	}
-
-	// initialize new P's
-	for i := old; i < nprocs; i++ {
-		pp := allp[i]
-		if pp == nil {
-			pp = new(p)
-		}
-		pp.init(i)
-		atomicstorep(unsafe.Pointer(&allp[i]), unsafe.Pointer(pp))
-	}
-
-	_g_ := getg()
-	if _g_.m.p != 0 && _g_.m.p.ptr().id < nprocs {
-		// continue to use the current P
-		_g_.m.p.ptr().status = _Prunning
-		_g_.m.p.ptr().mcache.prepareForSweep()
-	} else {
-		// release the current P and acquire allp[0].
-		//
-		// We must do this before destroying our current P
-		// because p.destroy itself has write barriers, so we
-		// need to do that from a valid P.
-		if _g_.m.p != 0 {
-			if trace.enabled {
-				// Pretend that we were descheduled
-				// and then scheduled again to keep
-				// the trace sane.
-				traceGoSched()
-				traceProcStop(_g_.m.p.ptr())
-			}
-			_g_.m.p.ptr().m = 0
-		}
-		_g_.m.p = 0
-		p := allp[0]
-		p.m = 0
-		p.status = _Pidle
-		acquirep(p)
-		if trace.enabled {
-			traceGoStart()
-		}
-	}
-
-	// g.m.p is now set, so we no longer need mcache0 for bootstrapping.
-	mcache0 = nil
-
-	// release resources from unused P's
-	for i := nprocs; i < old; i++ {
-		p := allp[i]
-		p.destroy()
-		// can't free P itself because it can be referenced by an M in syscall
-	}
-
-	// Trim allp.
-	if int32(len(allp)) != nprocs {
-		lock(&allpLock)
-		allp = allp[:nprocs]
-		idlepMask = idlepMask[:maskWords]
-		timerpMask = timerpMask[:maskWords]
-		unlock(&allpLock)
-	}
-
-	var runnablePs *p
-	for i := nprocs - 1; i >= 0; i-- {
-		p := allp[i]
-		if _g_.m.p.ptr() == p {
-			continue
-		}
-		p.status = _Pidle
-		if runqempty(p) {
-			pidleput(p)
-		} else {
-			p.m.set(mget())
-			p.link.set(runnablePs)
-			runnablePs = p
-		}
-	}
-	stealOrder.reset(uint32(nprocs))
-	var int32p *int32 = &gomaxprocs // make compiler check that gomaxprocs is an int32
-	atomic.Store((*uint32)(unsafe.Pointer(int32p)), uint32(nprocs))
-	return runnablePs
-}
-
-// Associate p and the current m.
-//
-// This function is allowed to have write barriers even if the caller
-// isn't because it immediately acquires _p_.
-//
-//go:yeswritebarrierrec
-func acquirep(_p_ *p) {
-	// Do the part that isn't allowed to have write barriers.
-	wirep(_p_)
-
-	// Have p; write barriers now allowed.
-
-	// Perform deferred mcache flush before this P can allocate
-	// from a potentially stale mcache.
-	_p_.mcache.prepareForSweep()
-
-	if trace.enabled {
-		traceProcStart()
-	}
-}
-
-// wirep is the first step of acquirep, which actually associates the
-// current M to _p_. This is broken out so we can disallow write
-// barriers for this part, since we don't yet have a P.
-//
-//go:nowritebarrierrec
-//go:nosplit
-func wirep(_p_ *p) {
-	_g_ := getg()
-
-	if _g_.m.p != 0 {
-		throw("wirep: already in go")
-	}
-	if _p_.m != 0 || _p_.status != _Pidle {
-		id := int64(0)
-		if _p_.m != 0 {
-			id = _p_.m.ptr().id
-		}
-		print("wirep: p->m=", _p_.m, "(", id, ") p->status=", _p_.status, "\n")
-		throw("wirep: invalid p state")
-	}
-	_g_.m.p.set(_p_)
-	_p_.m.set(_g_.m)
-	_p_.status = _Prunning
-}
-
-// Disassociate p and the current m.
-func releasep() *p {
-	_g_ := getg()
-
-	if _g_.m.p == 0 {
-		throw("releasep: invalid arg")
-	}
-	_p_ := _g_.m.p.ptr()
-	if _p_.m.ptr() != _g_.m || _p_.status != _Prunning {
-		print("releasep: m=", _g_.m, " m->p=", _g_.m.p.ptr(), " p->m=", hex(_p_.m), " p->status=", _p_.status, "\n")
-		throw("releasep: invalid p state")
-	}
-	if trace.enabled {
-		traceProcStop(_g_.m.p.ptr())
-	}
-	_g_.m.p = 0
-	_p_.m = 0
-	_p_.status = _Pidle
-	return _p_
-}
-
-func incidlelocked(v int32) {
-	lock(&sched.lock)
-	sched.nmidlelocked += v
-	if v > 0 {
-		checkdead()
-	}
-	unlock(&sched.lock)
-}
-
-// Check for deadlock situation.
-// The check is based on number of running M's, if 0 -> deadlock.
-// sched.lock must be held.
-func checkdead() {
-	assertLockHeld(&sched.lock)
-
-	// For -buildmode=c-shared or -buildmode=c-archive it's OK if
-	// there are no running goroutines. The calling program is
-	// assumed to be running.
-	if islibrary || isarchive {
-		return
-	}
-
-	// If we are dying because of a signal caught on an already idle thread,
-	// freezetheworld will cause all running threads to block.
-	// And runtime will essentially enter into deadlock state,
-	// except that there is a thread that will call exit soon.
-	if panicking > 0 {
-		return
-	}
-
-	// If we are not running under cgo, but we have an extra M then account
-	// for it. (It is possible to have an extra M on Windows without cgo to
-	// accommodate callbacks created by syscall.NewCallback. See issue #6751
-	// for details.)
-	var run0 int32
-	if !iscgo && cgoHasExtraM {
-		mp := lockextra(true)
-		haveExtraM := extraMCount > 0
-		unlockextra(mp)
-		if haveExtraM {
-			run0 = 1
-		}
-	}
-
-	run := mcount() - sched.nmidle - sched.nmidlelocked - sched.nmsys
-	if run > run0 {
-		return
-	}
-	if run < 0 {
-		print("runtime: checkdead: nmidle=", sched.nmidle, " nmidlelocked=", sched.nmidlelocked, " mcount=", mcount(), " nmsys=", sched.nmsys, "\n")
-		throw("checkdead: inconsistent counts")
-	}
-
-	grunning := 0
-	forEachG(func(gp *g) {
-		if isSystemGoroutine(gp, false) {
-			return
-		}
-		s := readgstatus(gp)
-		switch s &^ _Gscan {
-		case _Gwaiting,
-			_Gpreempted:
-			grunning++
-		case _Grunnable,
-			_Grunning,
-			_Gsyscall:
-			print("runtime: checkdead: find g ", gp.goid, " in status ", s, "\n")
-			throw("checkdead: runnable g")
-		}
-	})
-	if grunning == 0 { // possible if main goroutine calls runtime·Goexit()
-		unlock(&sched.lock) // unlock so that GODEBUG=scheddetail=1 doesn't hang
-		throw("no goroutines (main called runtime.Goexit) - deadlock!")
-	}
-
-	// Maybe jump time forward for playground.
-	if faketime != 0 {
-		when, _p_ := timeSleepUntil()
-		if _p_ != nil {
-			faketime = when
-			for pp := &sched.pidle; *pp != 0; pp = &(*pp).ptr().link {
-				if (*pp).ptr() == _p_ {
-					*pp = _p_.link
-					break
-				}
-			}
-			mp := mget()
-			if mp == nil {
-				// There should always be a free M since
-				// nothing is running.
-				throw("checkdead: no m for timer")
-			}
-			mp.nextp.set(_p_)
-			notewakeup(&mp.park)
-			return
-		}
-	}
-
-	// There are no goroutines running, so we can look at the P's.
-	for _, _p_ := range allp {
-		if len(_p_.timers) > 0 {
-			return
-		}
-	}
-
-	getg().m.throwing = -1 // do not dump full stacks
-	unlock(&sched.lock)    // unlock so that GODEBUG=scheddetail=1 doesn't hang
-	throw("all goroutines are asleep - deadlock!")
-}
-
-// forcegcperiod is the maximum time in nanoseconds between garbage
-// collections. If we go this long without a garbage collection, one
-// is forced to run.
-//
-// This is a variable for testing purposes. It normally doesn't change.
-var forcegcperiod int64 = 2 * 60 * 1e9
-
-// needSysmonWorkaround is true if the workaround for
-// golang.org/issue/42515 is needed on NetBSD.
-var needSysmonWorkaround bool = false
-
-// Always runs without a P, so write barriers are not allowed.
-//
-//go:nowritebarrierrec
-func sysmon() {
-	lock(&sched.lock)
-	sched.nmsys++
-	checkdead()
-	unlock(&sched.lock)
-
-	lasttrace := int64(0)
-	idle := 0 // how many cycles in succession we had not wokeup somebody
-	delay := uint32(0)
-
-	for {
-		if idle == 0 { // start with 20us sleep...
-			delay = 20
-		} else if idle > 50 { // start doubling the sleep after 1ms...
-			delay *= 2
-		}
-		if delay > 10*1000 { // up to 10ms
-			delay = 10 * 1000
-		}
-		usleep(delay)
-
-		// sysmon should not enter deep sleep if schedtrace is enabled so that
-		// it can print that information at the right time.
-		//
-		// It should also not enter deep sleep if there are any active P's so
-		// that it can retake P's from syscalls, preempt long running G's, and
-		// poll the network if all P's are busy for long stretches.
-		//
-		// It should wakeup from deep sleep if any P's become active either due
-		// to exiting a syscall or waking up due to a timer expiring so that it
-		// can resume performing those duties. If it wakes from a syscall it
-		// resets idle and delay as a bet that since it had retaken a P from a
-		// syscall before, it may need to do it again shortly after the
-		// application starts work again. It does not reset idle when waking
-		// from a timer to avoid adding system load to applications that spend
-		// most of their time sleeping.
-		now := nanotime()
-		if debug.schedtrace <= 0 && (sched.gcwaiting != 0 || atomic.Load(&sched.npidle) == uint32(gomaxprocs)) {
-			lock(&sched.lock)
-			if atomic.Load(&sched.gcwaiting) != 0 || atomic.Load(&sched.npidle) == uint32(gomaxprocs) {
-				syscallWake := false
-				next, _ := timeSleepUntil()
-				if next > now {
-					atomic.Store(&sched.sysmonwait, 1)
-					unlock(&sched.lock)
-					// Make wake-up period small enough
-					// for the sampling to be correct.
-					sleep := forcegcperiod / 2
-					if next-now < sleep {
-						sleep = next - now
-					}
-					shouldRelax := sleep >= osRelaxMinNS
-					if shouldRelax {
-						osRelax(true)
-					}
-					syscallWake = notetsleep(&sched.sysmonnote, sleep)
-					if shouldRelax {
-						osRelax(false)
-					}
-					lock(&sched.lock)
-					atomic.Store(&sched.sysmonwait, 0)
-					noteclear(&sched.sysmonnote)
-				}
-				if syscallWake {
-					idle = 0
-					delay = 20
-				}
-			}
-			unlock(&sched.lock)
-		}
-
-		lock(&sched.sysmonlock)
-		// Update now in case we blocked on sysmonnote or spent a long time
-		// blocked on schedlock or sysmonlock above.
-		now = nanotime()
-
-		// trigger libc interceptors if needed
-		if *cgo_yield != nil {
-			asmcgocall(*cgo_yield, nil)
-		}
-		// poll network if not polled for more than 10ms
-		lastpoll := int64(atomic.Load64(&sched.lastpoll))
-		if netpollinited() && lastpoll != 0 && lastpoll+10*1000*1000 < now {
-			atomic.Cas64(&sched.lastpoll, uint64(lastpoll), uint64(now))
-			list := netpoll(0) // non-blocking - returns list of goroutines
-			if !list.empty() {
-				// Need to decrement number of idle locked M's
-				// (pretending that one more is running) before injectglist.
-				// Otherwise it can lead to the following situation:
-				// injectglist grabs all P's but before it starts M's to run the P's,
-				// another M returns from syscall, finishes running its G,
-				// observes that there is no work to do and no other running M's
-				// and reports deadlock.
-				incidlelocked(-1)
-				injectglist(&list)
-				incidlelocked(1)
-			}
-		}
-		if GOOS == "netbsd" && needSysmonWorkaround {
-			// netpoll is responsible for waiting for timer
-			// expiration, so we typically don't have to worry
-			// about starting an M to service timers. (Note that
-			// sleep for timeSleepUntil above simply ensures sysmon
-			// starts running again when that timer expiration may
-			// cause Go code to run again).
-			//
-			// However, netbsd has a kernel bug that sometimes
-			// misses netpollBreak wake-ups, which can lead to
-			// unbounded delays servicing timers. If we detect this
-			// overrun, then startm to get something to handle the
-			// timer.
-			//
-			// See issue 42515 and
-			// https://gnats.netbsd.org/cgi-bin/query-pr-single.pl?number=50094.
-			if next, _ := timeSleepUntil(); next < now {
-				startm(nil, false)
-			}
-		}
-		if atomic.Load(&scavenge.sysmonWake) != 0 {
-			// Kick the scavenger awake if someone requested it.
-			wakeScavenger()
-		}
-		// retake P's blocked in syscalls
-		// and preempt long running G's
-		if retake(now) != 0 {
-			idle = 0
-		} else {
-			idle++
-		}
-		// check if we need to force a GC
-		if t := (gcTrigger{kind: gcTriggerTime, now: now}); t.test() && atomic.Load(&forcegc.idle) != 0 {
-			lock(&forcegc.lock)
-			forcegc.idle = 0
-			var list gList
-			list.push(forcegc.g)
-			injectglist(&list)
-			unlock(&forcegc.lock)
-		}
-		if debug.schedtrace > 0 && lasttrace+int64(debug.schedtrace)*1000000 <= now {
-			lasttrace = now
-			schedtrace(debug.scheddetail > 0)
-		}
-		unlock(&sched.sysmonlock)
-	}
-}
-
-type sysmontick struct {
-	schedtick   uint32
-	schedwhen   int64
-	syscalltick uint32
-	syscallwhen int64
-}
-
-// forcePreemptNS is the time slice given to a G before it is
-// preempted.
-const forcePreemptNS = 10 * 1000 * 1000 // 10ms
-
-func retake(now int64) uint32 {
-	n := 0
-	// Prevent allp slice changes. This lock will be completely
-	// uncontended unless we're already stopping the world.
-	lock(&allpLock)
-	// We can't use a range loop over allp because we may
-	// temporarily drop the allpLock. Hence, we need to re-fetch
-	// allp each time around the loop.
-	for i := 0; i < len(allp); i++ {
-		_p_ := allp[i]
-		if _p_ == nil {
-			// This can happen if procresize has grown
-			// allp but not yet created new Ps.
-			continue
-		}
-		pd := &_p_.sysmontick
-		s := _p_.status
-		sysretake := false
-		if s == _Prunning || s == _Psyscall {
-			// Preempt G if it's running for too long.
-			t := int64(_p_.schedtick)
-			if int64(pd.schedtick) != t {
-				pd.schedtick = uint32(t)
-				pd.schedwhen = now
-			} else if pd.schedwhen+forcePreemptNS <= now {
-				preemptone(_p_)
-				// In case of syscall, preemptone() doesn't
-				// work, because there is no M wired to P.
-				sysretake = true
-			}
-		}
-		if s == _Psyscall {
-			// Retake P from syscall if it's there for more than 1 sysmon tick (at least 20us).
-			t := int64(_p_.syscalltick)
-			if !sysretake && int64(pd.syscalltick) != t {
-				pd.syscalltick = uint32(t)
-				pd.syscallwhen = now
-				continue
-			}
-			// On the one hand we don't want to retake Ps if there is no other work to do,
-			// but on the other hand we want to retake them eventually
-			// because they can prevent the sysmon thread from deep sleep.
-			if runqempty(_p_) && atomic.Load(&sched.nmspinning)+atomic.Load(&sched.npidle) > 0 && pd.syscallwhen+10*1000*1000 > now {
-				continue
-			}
-			// Drop allpLock so we can take sched.lock.
-			unlock(&allpLock)
-			// Need to decrement number of idle locked M's
-			// (pretending that one more is running) before the CAS.
-			// Otherwise the M from which we retake can exit the syscall,
-			// increment nmidle and report deadlock.
-			incidlelocked(-1)
-			if atomic.Cas(&_p_.status, s, _Pidle) {
-				if trace.enabled {
-					traceGoSysBlock(_p_)
-					traceProcStop(_p_)
-				}
-				n++
-				_p_.syscalltick++
-				handoffp(_p_)
-			}
-			incidlelocked(1)
-			lock(&allpLock)
-		}
-	}
-	unlock(&allpLock)
-	return uint32(n)
-}
-
-// Tell all goroutines that they have been preempted and they should stop.
-// This function is purely best-effort. It can fail to inform a goroutine if a
-// processor just started running it.
-// No locks need to be held.
-// Returns true if preemption request was issued to at least one goroutine.
-func preemptall() bool {
-	res := false
-	for _, _p_ := range allp {
-		if _p_.status != _Prunning {
-			continue
-		}
-		if preemptone(_p_) {
-			res = true
-		}
-	}
-	return res
-}
-
-// Tell the goroutine running on processor P to stop.
-// This function is purely best-effort. It can incorrectly fail to inform the
-// goroutine. It can inform the wrong goroutine. Even if it informs the
-// correct goroutine, that goroutine might ignore the request if it is
-// simultaneously executing newstack.
-// No lock needs to be held.
-// Returns true if preemption request was issued.
-// The actual preemption will happen at some point in the future
-// and will be indicated by the gp->status no longer being
-// Grunning
-func preemptone(_p_ *p) bool {
-	mp := _p_.m.ptr()
-	if mp == nil || mp == getg().m {
-		return false
-	}
-	gp := mp.curg
-	if gp == nil || gp == mp.g0 {
-		return false
-	}
-
-	gp.preempt = true
-
-	// Every call in a goroutine checks for stack overflow by
-	// comparing the current stack pointer to gp->stackguard0.
-	// Setting gp->stackguard0 to StackPreempt folds
-	// preemption into the normal stack overflow check.
-	gp.stackguard0 = stackPreempt
-
-	// Request an async preemption of this P.
-	if preemptMSupported && debug.asyncpreemptoff == 0 {
-		_p_.preempt = true
-		preemptM(mp)
-	}
-
-	return true
-}
-
-var starttime int64
-
-func schedtrace(detailed bool) {
-	now := nanotime()
-	if starttime == 0 {
-		starttime = now
-	}
-
-	lock(&sched.lock)
-	print("SCHED ", (now-starttime)/1e6, "ms: gomaxprocs=", gomaxprocs, " idleprocs=", sched.npidle, " threads=", mcount(), " spinningthreads=", sched.nmspinning, " idlethreads=", sched.nmidle, " runqueue=", sched.runqsize)
-	if detailed {
-		print(" gcwaiting=", sched.gcwaiting, " nmidlelocked=", sched.nmidlelocked, " stopwait=", sched.stopwait, " sysmonwait=", sched.sysmonwait, "\n")
-	}
-	// We must be careful while reading data from P's, M's and G's.
-	// Even if we hold schedlock, most data can be changed concurrently.
-	// E.g. (p->m ? p->m->id : -1) can crash if p->m changes from non-nil to nil.
-	for i, _p_ := range allp {
-		mp := _p_.m.ptr()
-		h := atomic.Load(&_p_.runqhead)
-		t := atomic.Load(&_p_.runqtail)
-		if detailed {
-			id := int64(-1)
-			if mp != nil {
-				id = mp.id
-			}
-			print("  P", i, ": status=", _p_.status, " schedtick=", _p_.schedtick, " syscalltick=", _p_.syscalltick, " m=", id, " runqsize=", t-h, " gfreecnt=", _p_.gFree.n, " timerslen=", len(_p_.timers), "\n")
-		} else {
-			// In non-detailed mode format lengths of per-P run queues as:
-			// [len1 len2 len3 len4]
-			print(" ")
-			if i == 0 {
-				print("[")
-			}
-			print(t - h)
-			if i == len(allp)-1 {
-				print("]\n")
-			}
-		}
-	}
-
-	if !detailed {
-		unlock(&sched.lock)
-		return
-	}
-
-	for mp := allm; mp != nil; mp = mp.alllink {
-		_p_ := mp.p.ptr()
-		gp := mp.curg
-		lockedg := mp.lockedg.ptr()
-		id1 := int32(-1)
-		if _p_ != nil {
-			id1 = _p_.id
-		}
-		id2 := int64(-1)
-		if gp != nil {
-			id2 = gp.goid
-		}
-		id3 := int64(-1)
-		if lockedg != nil {
-			id3 = lockedg.goid
-		}
-		print("  M", mp.id, ": p=", id1, " curg=", id2, " mallocing=", mp.mallocing, " throwing=", mp.throwing, " preemptoff=", mp.preemptoff, ""+" locks=", mp.locks, " dying=", mp.dying, " spinning=", mp.spinning, " blocked=", mp.blocked, " lockedg=", id3, "\n")
-	}
-
-	forEachG(func(gp *g) {
-		mp := gp.m
-		lockedm := gp.lockedm.ptr()
-		id1 := int64(-1)
-		if mp != nil {
-			id1 = mp.id
-		}
-		id2 := int64(-1)
-		if lockedm != nil {
-			id2 = lockedm.id
-		}
-		print("  G", gp.goid, ": status=", readgstatus(gp), "(", gp.waitreason.String(), ") m=", id1, " lockedm=", id2, "\n")
-	})
-	unlock(&sched.lock)
-}
-
-// schedEnableUser enables or disables the scheduling of user
-// goroutines.
-//
-// This does not stop already running user goroutines, so the caller
-// should first stop the world when disabling user goroutines.
-func schedEnableUser(enable bool) {
-	lock(&sched.lock)
-	if sched.disable.user == !enable {
-		unlock(&sched.lock)
-		return
-	}
-	sched.disable.user = !enable
-	if enable {
-		n := sched.disable.n
-		sched.disable.n = 0
-		globrunqputbatch(&sched.disable.runnable, n)
-		unlock(&sched.lock)
-		for ; n != 0 && sched.npidle != 0; n-- {
-			startm(nil, false)
-		}
-	} else {
-		unlock(&sched.lock)
-	}
-}
-
-// schedEnabled reports whether gp should be scheduled. It returns
-// false is scheduling of gp is disabled.
-//
-// sched.lock must be held.
-func schedEnabled(gp *g) bool {
-	assertLockHeld(&sched.lock)
-
-	if sched.disable.user {
-		return isSystemGoroutine(gp, true)
-	}
-	return true
-}
-
-// Put mp on midle list.
-// sched.lock must be held.
-// May run during STW, so write barriers are not allowed.
-//go:nowritebarrierrec
-func mput(mp *m) {
-	assertLockHeld(&sched.lock)
-
-	mp.schedlink = sched.midle
-	sched.midle.set(mp)
-	sched.nmidle++
-	checkdead()
-}
-
-// Try to get an m from midle list.
-// sched.lock must be held.
-// May run during STW, so write barriers are not allowed.
-//go:nowritebarrierrec
-func mget() *m {
-	assertLockHeld(&sched.lock)
-
-	mp := sched.midle.ptr()
-	if mp != nil {
-		sched.midle = mp.schedlink
-		sched.nmidle--
-	}
-	return mp
-}
-
-// Put gp on the global runnable queue.
-// sched.lock must be held.
-// May run during STW, so write barriers are not allowed.
-//go:nowritebarrierrec
-func globrunqput(gp *g) {
-	assertLockHeld(&sched.lock)
-
-	sched.runq.pushBack(gp)
-	sched.runqsize++
-}
-
-// Put gp at the head of the global runnable queue.
-// sched.lock must be held.
-// May run during STW, so write barriers are not allowed.
-//go:nowritebarrierrec
-func globrunqputhead(gp *g) {
-	assertLockHeld(&sched.lock)
-
-	sched.runq.push(gp)
-	sched.runqsize++
-}
-
-// Put a batch of runnable goroutines on the global runnable queue.
-// This clears *batch.
-// sched.lock must be held.
-// May run during STW, so write barriers are not allowed.
-//go:nowritebarrierrec
-func globrunqputbatch(batch *gQueue, n int32) {
-	assertLockHeld(&sched.lock)
-
-	sched.runq.pushBackAll(*batch)
-	sched.runqsize += n
-	*batch = gQueue{}
-}
-
-// Try get a batch of G's from the global runnable queue.
-// sched.lock must be held.
-func globrunqget(_p_ *p, max int32) *g {
-	assertLockHeld(&sched.lock)
-
-	if sched.runqsize == 0 {
-		return nil
-	}
-
-	n := sched.runqsize/gomaxprocs + 1
-	if n > sched.runqsize {
-		n = sched.runqsize
-	}
-	if max > 0 && n > max {
-		n = max
-	}
-	if n > int32(len(_p_.runq))/2 {
-		n = int32(len(_p_.runq)) / 2
-	}
-
-	sched.runqsize -= n
-
-	gp := sched.runq.pop()
-	n--
-	for ; n > 0; n-- {
-		gp1 := sched.runq.pop()
-		runqput(_p_, gp1, false)
-	}
-	return gp
-}
-
-// pMask is an atomic bitstring with one bit per P.
-type pMask []uint32
-
-// read returns true if P id's bit is set.
-func (p pMask) read(id uint32) bool {
-	word := id / 32
-	mask := uint32(1) << (id % 32)
-	return (atomic.Load(&p[word]) & mask) != 0
-}
-
-// set sets P id's bit.
-func (p pMask) set(id int32) {
-	word := id / 32
-	mask := uint32(1) << (id % 32)
-	atomic.Or(&p[word], mask)
-}
-
-// clear clears P id's bit.
-func (p pMask) clear(id int32) {
-	word := id / 32
-	mask := uint32(1) << (id % 32)
-	atomic.And(&p[word], ^mask)
-}
-
-// updateTimerPMask clears pp's timer mask if it has no timers on its heap.
-//
-// Ideally, the timer mask would be kept immediately consistent on any timer
-// operations. Unfortunately, updating a shared global data structure in the
-// timer hot path adds too much overhead in applications frequently switching
-// between no timers and some timers.
-//
-// As a compromise, the timer mask is updated only on pidleget / pidleput. A
-// running P (returned by pidleget) may add a timer at any time, so its mask
-// must be set. An idle P (passed to pidleput) cannot add new timers while
-// idle, so if it has no timers at that time, its mask may be cleared.
-//
-// Thus, we get the following effects on timer-stealing in findrunnable:
-//
-// * Idle Ps with no timers when they go idle are never checked in findrunnable
-//   (for work- or timer-stealing; this is the ideal case).
-// * Running Ps must always be checked.
-// * Idle Ps whose timers are stolen must continue to be checked until they run
-//   again, even after timer expiration.
-//
-// When the P starts running again, the mask should be set, as a timer may be
-// added at any time.
-//
-// TODO(prattmic): Additional targeted updates may improve the above cases.
-// e.g., updating the mask when stealing a timer.
-func updateTimerPMask(pp *p) {
-	if atomic.Load(&pp.numTimers) > 0 {
-		return
-	}
-
-	// Looks like there are no timers, however another P may transiently
-	// decrement numTimers when handling a timerModified timer in
-	// checkTimers. We must take timersLock to serialize with these changes.
-	lock(&pp.timersLock)
-	if atomic.Load(&pp.numTimers) == 0 {
-		timerpMask.clear(pp.id)
-	}
-	unlock(&pp.timersLock)
-}
-
-// pidleput puts p to on the _Pidle list.
-//
-// This releases ownership of p. Once sched.lock is released it is no longer
-// safe to use p.
-//
-// sched.lock must be held.
-//
-// May run during STW, so write barriers are not allowed.
-//go:nowritebarrierrec
-func pidleput(_p_ *p) {
-	assertLockHeld(&sched.lock)
-
-	if !runqempty(_p_) {
-		throw("pidleput: P has non-empty run queue")
-	}
-	updateTimerPMask(_p_) // clear if there are no timers.
-	idlepMask.set(_p_.id)
-	_p_.link = sched.pidle
-	sched.pidle.set(_p_)
-	atomic.Xadd(&sched.npidle, 1) // TODO: fast atomic
-}
-
-// pidleget tries to get a p from the _Pidle list, acquiring ownership.
-//
-// sched.lock must be held.
-//
-// May run during STW, so write barriers are not allowed.
-//go:nowritebarrierrec
-func pidleget() *p {
-	assertLockHeld(&sched.lock)
-
-	_p_ := sched.pidle.ptr()
-	if _p_ != nil {
-		// Timer may get added at any time now.
-		timerpMask.set(_p_.id)
-		idlepMask.clear(_p_.id)
-		sched.pidle = _p_.link
-		atomic.Xadd(&sched.npidle, -1) // TODO: fast atomic
-	}
-	return _p_
-}
-
-// runqempty reports whether _p_ has no Gs on its local run queue.
-// It never returns true spuriously.
-func runqempty(_p_ *p) bool {
-	// Defend against a race where 1) _p_ has G1 in runqnext but runqhead == runqtail,
-	// 2) runqput on _p_ kicks G1 to the runq, 3) runqget on _p_ empties runqnext.
-	// Simply observing that runqhead == runqtail and then observing that runqnext == nil
-	// does not mean the queue is empty.
-	for {
-		head := atomic.Load(&_p_.runqhead)
-		tail := atomic.Load(&_p_.runqtail)
-		runnext := atomic.Loaduintptr((*uintptr)(unsafe.Pointer(&_p_.runnext)))
-		if tail == atomic.Load(&_p_.runqtail) {
-			return head == tail && runnext == 0
-		}
-	}
-}
-
-// To shake out latent assumptions about scheduling order,
-// we introduce some randomness into scheduling decisions
-// when running with the race detector.
-// The need for this was made obvious by changing the
-// (deterministic) scheduling order in Go 1.5 and breaking
-// many poorly-written tests.
-// With the randomness here, as long as the tests pass
-// consistently with -race, they shouldn't have latent scheduling
-// assumptions.
-const randomizeScheduler = raceenabled
-
-// runqput tries to put g on the local runnable queue.
-// If next is false, runqput adds g to the tail of the runnable queue.
-// If next is true, runqput puts g in the _p_.runnext slot.
-// If the run queue is full, runnext puts g on the global queue.
-// Executed only by the owner P.
-func runqput(_p_ *p, gp *g, next bool) {
-	if randomizeScheduler && next && fastrandn(2) == 0 {
-		next = false
-	}
-
-	if next {
-	retryNext:
-		oldnext := _p_.runnext
-		if !_p_.runnext.cas(oldnext, guintptr(unsafe.Pointer(gp))) {
-			goto retryNext
-		}
-		if oldnext == 0 {
-			return
-		}
-		// Kick the old runnext out to the regular run queue.
-		gp = oldnext.ptr()
-	}
-
-retry:
-	h := atomic.LoadAcq(&_p_.runqhead) // load-acquire, synchronize with consumers
-	t := _p_.runqtail
-	if t-h < uint32(len(_p_.runq)) {
-		_p_.runq[t%uint32(len(_p_.runq))].set(gp)
-		atomic.StoreRel(&_p_.runqtail, t+1) // store-release, makes the item available for consumption
-		return
-	}
-	if runqputslow(_p_, gp, h, t) {
-		return
-	}
-	// the queue is not full, now the put above must succeed
-	goto retry
-}
-
-// Put g and a batch of work from local runnable queue on global queue.
-// Executed only by the owner P.
-func runqputslow(_p_ *p, gp *g, h, t uint32) bool {
-	var batch [len(_p_.runq)/2 + 1]*g
-
-	// First, grab a batch from local queue.
-	n := t - h
-	n = n / 2
-	if n != uint32(len(_p_.runq)/2) {
-		throw("runqputslow: queue is not full")
-	}
-	for i := uint32(0); i < n; i++ {
-		batch[i] = _p_.runq[(h+i)%uint32(len(_p_.runq))].ptr()
-	}
-	if !atomic.CasRel(&_p_.runqhead, h, h+n) { // cas-release, commits consume
-		return false
-	}
-	batch[n] = gp
-
-	if randomizeScheduler {
-		for i := uint32(1); i <= n; i++ {
-			j := fastrandn(i + 1)
-			batch[i], batch[j] = batch[j], batch[i]
-		}
-	}
-
-	// Link the goroutines.
-	for i := uint32(0); i < n; i++ {
-		batch[i].schedlink.set(batch[i+1])
-	}
-	var q gQueue
-	q.head.set(batch[0])
-	q.tail.set(batch[n])
-
-	// Now put the batch on global queue.
-	lock(&sched.lock)
-	globrunqputbatch(&q, int32(n+1))
-	unlock(&sched.lock)
-	return true
-}
-
-// runqputbatch tries to put all the G's on q on the local runnable queue.
-// If the queue is full, they are put on the global queue; in that case
-// this will temporarily acquire the scheduler lock.
-// Executed only by the owner P.
-func runqputbatch(pp *p, q *gQueue, qsize int) {
-	h := atomic.LoadAcq(&pp.runqhead)
-	t := pp.runqtail
-	n := uint32(0)
-	for !q.empty() && t-h < uint32(len(pp.runq)) {
-		gp := q.pop()
-		pp.runq[t%uint32(len(pp.runq))].set(gp)
-		t++
-		n++
-	}
-	qsize -= int(n)
-
-	if randomizeScheduler {
-		off := func(o uint32) uint32 {
-			return (pp.runqtail + o) % uint32(len(pp.runq))
-		}
-		for i := uint32(1); i < n; i++ {
-			j := fastrandn(i + 1)
-			pp.runq[off(i)], pp.runq[off(j)] = pp.runq[off(j)], pp.runq[off(i)]
-		}
-	}
-
-	atomic.StoreRel(&pp.runqtail, t)
-	if !q.empty() {
-		lock(&sched.lock)
-		globrunqputbatch(q, int32(qsize))
-		unlock(&sched.lock)
-	}
-}
-
-// Get g from local runnable queue.
-// If inheritTime is true, gp should inherit the remaining time in the
-// current time slice. Otherwise, it should start a new time slice.
-// Executed only by the owner P.
-func runqget(_p_ *p) (gp *g, inheritTime bool) {
-	// If there's a runnext, it's the next G to run.
-	next := _p_.runnext
-	// If the runnext is non-0 and the CAS fails, it could only have been stolen by another P,
-	// because other Ps can race to set runnext to 0, but only the current P can set it to non-0.
-	// Hence, there's no need to retry this CAS if it falls.
-	if next != 0 && _p_.runnext.cas(next, 0) {
-		return next.ptr(), true
-	}
-
-	for {
-		h := atomic.LoadAcq(&_p_.runqhead) // load-acquire, synchronize with other consumers
-		t := _p_.runqtail
-		if t == h {
-			return nil, false
-		}
-		gp := _p_.runq[h%uint32(len(_p_.runq))].ptr()
-		if atomic.CasRel(&_p_.runqhead, h, h+1) { // cas-release, commits consume
-			return gp, false
-		}
-	}
-}
-
-// runqdrain drains the local runnable queue of _p_ and returns all goroutines in it.
-// Executed only by the owner P.
-func runqdrain(_p_ *p) (drainQ gQueue, n uint32) {
-	oldNext := _p_.runnext
-	if oldNext != 0 && _p_.runnext.cas(oldNext, 0) {
-		drainQ.pushBack(oldNext.ptr())
-		n++
-	}
-
-retry:
-	h := atomic.LoadAcq(&_p_.runqhead) // load-acquire, synchronize with other consumers
-	t := _p_.runqtail
-	qn := t - h
-	if qn == 0 {
-		return
-	}
-	if qn > uint32(len(_p_.runq)) { // read inconsistent h and t
-		goto retry
-	}
-
-	if !atomic.CasRel(&_p_.runqhead, h, h+qn) { // cas-release, commits consume
-		goto retry
-	}
-
-	// We've inverted the order in which it gets G's from the local P's runnable queue
-	// and then advances the head pointer because we don't want to mess up the statuses of G's
-	// while runqdrain() and runqsteal() are running in parallel.
-	// Thus we should advance the head pointer before draining the local P into a gQueue,
-	// so that we can update any gp.schedlink only after we take the full ownership of G,
-	// meanwhile, other P's can't access to all G's in local P's runnable queue and steal them.
-	// See https://groups.google.com/g/golang-dev/c/0pTKxEKhHSc/m/6Q85QjdVBQAJ for more details.
-	for i := uint32(0); i < qn; i++ {
-		gp := _p_.runq[(h+i)%uint32(len(_p_.runq))].ptr()
-		drainQ.pushBack(gp)
-		n++
-	}
-	return
-}
-
-// Grabs a batch of goroutines from _p_'s runnable queue into batch.
-// Batch is a ring buffer starting at batchHead.
-// Returns number of grabbed goroutines.
-// Can be executed by any P.
-func runqgrab(_p_ *p, batch *[256]guintptr, batchHead uint32, stealRunNextG bool) uint32 {
-	for {
-		h := atomic.LoadAcq(&_p_.runqhead) // load-acquire, synchronize with other consumers
-		t := atomic.LoadAcq(&_p_.runqtail) // load-acquire, synchronize with the producer
-		n := t - h
-		n = n - n/2
-		if n == 0 {
-			if stealRunNextG {
-				// Try to steal from _p_.runnext.
-				if next := _p_.runnext; next != 0 {
-					if _p_.status == _Prunning {
-						// Sleep to ensure that _p_ isn't about to run the g
-						// we are about to steal.
-						// The important use case here is when the g running
-						// on _p_ ready()s another g and then almost
-						// immediately blocks. Instead of stealing runnext
-						// in this window, back off to give _p_ a chance to
-						// schedule runnext. This will avoid thrashing gs
-						// between different Ps.
-						// A sync chan send/recv takes ~50ns as of time of
-						// writing, so 3us gives ~50x overshoot.
-						if GOOS != "windows" {
-							usleep(3)
-						} else {
-							// On windows system timer granularity is
-							// 1-15ms, which is way too much for this
-							// optimization. So just yield.
-							osyield()
-						}
-					}
-					if !_p_.runnext.cas(next, 0) {
-						continue
-					}
-					batch[batchHead%uint32(len(batch))] = next
-					return 1
-				}
-			}
-			return 0
-		}
-		if n > uint32(len(_p_.runq)/2) { // read inconsistent h and t
-			continue
-		}
-		for i := uint32(0); i < n; i++ {
-			g := _p_.runq[(h+i)%uint32(len(_p_.runq))]
-			batch[(batchHead+i)%uint32(len(batch))] = g
-		}
-		if atomic.CasRel(&_p_.runqhead, h, h+n) { // cas-release, commits consume
-			return n
-		}
-	}
-}
-
-// Steal half of elements from local runnable queue of p2
-// and put onto local runnable queue of p.
-// Returns one of the stolen elements (or nil if failed).
-func runqsteal(_p_, p2 *p, stealRunNextG bool) *g {
-	t := _p_.runqtail
-	n := runqgrab(p2, &_p_.runq, t, stealRunNextG)
-	if n == 0 {
-		return nil
-	}
-	n--
-	gp := _p_.runq[(t+n)%uint32(len(_p_.runq))].ptr()
-	if n == 0 {
-		return gp
-	}
-	h := atomic.LoadAcq(&_p_.runqhead) // load-acquire, synchronize with consumers
-	if t-h+n >= uint32(len(_p_.runq)) {
-		throw("runqsteal: runq overflow")
-	}
-	atomic.StoreRel(&_p_.runqtail, t+n) // store-release, makes the item available for consumption
-	return gp
-}
-
-// A gQueue is a dequeue of Gs linked through g.schedlink. A G can only
-// be on one gQueue or gList at a time.
-type gQueue struct {
-	head guintptr
-	tail guintptr
-}
-
-// empty reports whether q is empty.
-func (q *gQueue) empty() bool {
-	return q.head == 0
-}
-
-// push adds gp to the head of q.
-func (q *gQueue) push(gp *g) {
-	gp.schedlink = q.head
-	q.head.set(gp)
-	if q.tail == 0 {
-		q.tail.set(gp)
-	}
-}
-
-// pushBack adds gp to the tail of q.
-func (q *gQueue) pushBack(gp *g) {
-	gp.schedlink = 0
-	if q.tail != 0 {
-		q.tail.ptr().schedlink.set(gp)
-	} else {
-		q.head.set(gp)
-	}
-	q.tail.set(gp)
-}
-
-// pushBackAll adds all Gs in q2 to the tail of q. After this q2 must
-// not be used.
-func (q *gQueue) pushBackAll(q2 gQueue) {
-	if q2.tail == 0 {
-		return
-	}
-	q2.tail.ptr().schedlink = 0
-	if q.tail != 0 {
-		q.tail.ptr().schedlink = q2.head
-	} else {
-		q.head = q2.head
-	}
-	q.tail = q2.tail
-}
-
-// pop removes and returns the head of queue q. It returns nil if
-// q is empty.
-func (q *gQueue) pop() *g {
-	gp := q.head.ptr()
-	if gp != nil {
-		q.head = gp.schedlink
-		if q.head == 0 {
-			q.tail = 0
-		}
-	}
-	return gp
-}
-
-// popList takes all Gs in q and returns them as a gList.
-func (q *gQueue) popList() gList {
-	stack := gList{q.head}
-	*q = gQueue{}
-	return stack
-}
-
-// A gList is a list of Gs linked through g.schedlink. A G can only be
-// on one gQueue or gList at a time.
-type gList struct {
-	head guintptr
-}
-
-// empty reports whether l is empty.
-func (l *gList) empty() bool {
-	return l.head == 0
-}
-
-// push adds gp to the head of l.
-func (l *gList) push(gp *g) {
-	gp.schedlink = l.head
-	l.head.set(gp)
-}
-
-// pushAll prepends all Gs in q to l.
-func (l *gList) pushAll(q gQueue) {
-	if !q.empty() {
-		q.tail.ptr().schedlink = l.head
-		l.head = q.head
-	}
-}
-
-// pop removes and returns the head of l. If l is empty, it returns nil.
-func (l *gList) pop() *g {
-	gp := l.head.ptr()
-	if gp != nil {
-		l.head = gp.schedlink
-	}
-	return gp
-}
-
-//go:linkname setMaxThreads runtime/debug.setMaxThreads
-func setMaxThreads(in int) (out int) {
-	lock(&sched.lock)
-	out = int(sched.maxmcount)
-	if in > 0x7fffffff { // MaxInt32
-		sched.maxmcount = 0x7fffffff
-	} else {
-		sched.maxmcount = int32(in)
-	}
-	checkmcount()
-	unlock(&sched.lock)
-	return
-}
-
-//go:nosplit
-func procPin() int {
-	_g_ := getg()
-	mp := _g_.m
-
-	mp.locks++
-	return int(mp.p.ptr().id)
-}
-
-//go:nosplit
-func procUnpin() {
-	_g_ := getg()
-	_g_.m.locks--
-}
-
-//go:linkname sync_runtime_procPin sync.runtime_procPin
-//go:nosplit
-func sync_runtime_procPin() int {
-	return procPin()
-}
-
-//go:linkname sync_runtime_procUnpin sync.runtime_procUnpin
-//go:nosplit
-func sync_runtime_procUnpin() {
-	procUnpin()
-}
-
-//go:linkname sync_atomic_runtime_procPin sync/atomic.runtime_procPin
-//go:nosplit
-func sync_atomic_runtime_procPin() int {
-	return procPin()
-}
-
-//go:linkname sync_atomic_runtime_procUnpin sync/atomic.runtime_procUnpin
-//go:nosplit
-func sync_atomic_runtime_procUnpin() {
-	procUnpin()
-}
-
-// Active spinning for sync.Mutex.
-//go:linkname sync_runtime_canSpin sync.runtime_canSpin
-//go:nosplit
-func sync_runtime_canSpin(i int) bool {
-	// sync.Mutex is cooperative, so we are conservative with spinning.
-	// Spin only few times and only if running on a multicore machine and
-	// GOMAXPROCS>1 and there is at least one other running P and local runq is empty.
-	// As opposed to runtime mutex we don't do passive spinning here,
-	// because there can be work on global runq or on other Ps.
-	if i >= active_spin || ncpu <= 1 || gomaxprocs <= int32(sched.npidle+sched.nmspinning)+1 {
-		return false
-	}
-	if p := getg().m.p.ptr(); !runqempty(p) {
-		return false
-	}
-	return true
-}
-
-//go:linkname sync_runtime_doSpin sync.runtime_doSpin
-//go:nosplit
-func sync_runtime_doSpin() {
-	procyield(active_spin_cnt)
-}
-
-var stealOrder randomOrder
-
-// randomOrder/randomEnum are helper types for randomized work stealing.
-// They allow to enumerate all Ps in different pseudo-random orders without repetitions.
-// The algorithm is based on the fact that if we have X such that X and GOMAXPROCS
-// are coprime, then a sequences of (i + X) % GOMAXPROCS gives the required enumeration.
-type randomOrder struct {
-	count    uint32
-	coprimes []uint32
-}
-
-type randomEnum struct {
-	i     uint32
-	count uint32
-	pos   uint32
-	inc   uint32
-}
-
-func (ord *randomOrder) reset(count uint32) {
-	ord.count = count
-	ord.coprimes = ord.coprimes[:0]
-	for i := uint32(1); i <= count; i++ {
-		if gcd(i, count) == 1 {
-			ord.coprimes = append(ord.coprimes, i)
-		}
-	}
-}
-
-func (ord *randomOrder) start(i uint32) randomEnum {
-	return randomEnum{
-		count: ord.count,
-		pos:   i % ord.count,
-		inc:   ord.coprimes[i%uint32(len(ord.coprimes))],
-	}
-}
-
-func (enum *randomEnum) done() bool {
-	return enum.i == enum.count
-}
-
-func (enum *randomEnum) next() {
-	enum.i++
-	enum.pos = (enum.pos + enum.inc) % enum.count
-}
-
-func (enum *randomEnum) position() uint32 {
-	return enum.pos
-}
-
-func gcd(a, b uint32) uint32 {
-	for b != 0 {
-		a, b = b, a%b
-	}
-	return a
-}
-
-// An initTask represents the set of initializations that need to be done for a package.
-// Keep in sync with ../../test/initempty.go:initTask
-type initTask struct {
-	// TODO: pack the first 3 fields more tightly?
-	state uintptr // 0 = uninitialized, 1 = in progress, 2 = done
-	ndeps uintptr
-	nfns  uintptr
-	// followed by ndeps instances of an *initTask, one per package depended on
-	// followed by nfns pcs, one per init function to run
-}
-
-// inittrace stores statistics for init functions which are
-// updated by malloc and newproc when active is true.
-var inittrace tracestat
-
-type tracestat struct {
-	active bool   // init tracing activation status
-	id     int64  // init goroutine id
-	allocs uint64 // heap allocations
-	bytes  uint64 // heap allocated bytes
-}
-
-func doInit(t *initTask) {
-	switch t.state {
-	case 2: // fully initialized
-		return
-	case 1: // initialization in progress
-		throw("recursive call during initialization - linker skew")
-	default: // not initialized yet
-		t.state = 1 // initialization in progress
-
-		for i := uintptr(0); i < t.ndeps; i++ {
-			p := add(unsafe.Pointer(t), (3+i)*goarch.PtrSize)
-			t2 := *(**initTask)(p)
-			doInit(t2)
-		}
-
-		if t.nfns == 0 {
-			t.state = 2 // initialization done
-			return
-		}
-
-		var (
-			start  int64
-			before tracestat
-		)
-
-		if inittrace.active {
-			start = nanotime()
-			// Load stats non-atomically since tracinit is updated only by this init goroutine.
-			before = inittrace
-		}
-
-		firstFunc := add(unsafe.Pointer(t), (3+t.ndeps)*goarch.PtrSize)
-		for i := uintptr(0); i < t.nfns; i++ {
-			p := add(firstFunc, i*goarch.PtrSize)
-			f := *(*func())(unsafe.Pointer(&p))
-			f()
-		}
-
-		if inittrace.active {
-			end := nanotime()
-			// Load stats non-atomically since tracinit is updated only by this init goroutine.
-			after := inittrace
-
-			f := *(*func())(unsafe.Pointer(&firstFunc))
-			pkg := funcpkgpath(findfunc(abi.FuncPCABIInternal(f)))
-
-			var sbuf [24]byte
-			print("init ", pkg, " @")
-			print(string(fmtNSAsMS(sbuf[:], uint64(start-runtimeInitTime))), " ms, ")
-			print(string(fmtNSAsMS(sbuf[:], uint64(end-start))), " ms clock, ")
-			print(string(itoa(sbuf[:], after.bytes-before.bytes)), " bytes, ")
-			print(string(itoa(sbuf[:], after.allocs-before.allocs)), " allocs")
-			print("\n")
-		}
-
-		t.state = 2 // initialization done
-	}
-}
diff --git a/contrib/go/_std_1.18/src/runtime/profbuf.go b/contrib/go/_std_1.18/src/runtime/profbuf.go
deleted file mode 100644
index f40881aed5..0000000000
--- a/contrib/go/_std_1.18/src/runtime/profbuf.go
+++ /dev/null
@@ -1,561 +0,0 @@
-// Copyright 2017 The Go Authors.  All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"runtime/internal/atomic"
-	"unsafe"
-)
-
-// A profBuf is a lock-free buffer for profiling events,
-// safe for concurrent use by one reader and one writer.
-// The writer may be a signal handler running without a user g.
-// The reader is assumed to be a user g.
-//
-// Each logged event corresponds to a fixed size header, a list of
-// uintptrs (typically a stack), and exactly one unsafe.Pointer tag.
-// The header and uintptrs are stored in the circular buffer data and the
-// tag is stored in a circular buffer tags, running in parallel.
-// In the circular buffer data, each event takes 2+hdrsize+len(stk)
-// words: the value 2+hdrsize+len(stk), then the time of the event, then
-// hdrsize words giving the fixed-size header, and then len(stk) words
-// for the stack.
-//
-// The current effective offsets into the tags and data circular buffers
-// for reading and writing are stored in the high 30 and low 32 bits of r and w.
-// The bottom bits of the high 32 are additional flag bits in w, unused in r.
-// "Effective" offsets means the total number of reads or writes, mod 2^length.
-// The offset in the buffer is the effective offset mod the length of the buffer.
-// To make wraparound mod 2^length match wraparound mod length of the buffer,
-// the length of the buffer must be a power of two.
-//
-// If the reader catches up to the writer, a flag passed to read controls
-// whether the read blocks until more data is available. A read returns a
-// pointer to the buffer data itself; the caller is assumed to be done with
-// that data at the next read. The read offset rNext tracks the next offset to
-// be returned by read. By definition, r ≤ rNext ≤ w (before wraparound),
-// and rNext is only used by the reader, so it can be accessed without atomics.
-//
-// If the writer gets ahead of the reader, so that the buffer fills,
-// future writes are discarded and replaced in the output stream by an
-// overflow entry, which has size 2+hdrsize+1, time set to the time of
-// the first discarded write, a header of all zeroed words, and a "stack"
-// containing one word, the number of discarded writes.
-//
-// Between the time the buffer fills and the buffer becomes empty enough
-// to hold more data, the overflow entry is stored as a pending overflow
-// entry in the fields overflow and overflowTime. The pending overflow
-// entry can be turned into a real record by either the writer or the
-// reader. If the writer is called to write a new record and finds that
-// the output buffer has room for both the pending overflow entry and the
-// new record, the writer emits the pending overflow entry and the new
-// record into the buffer. If the reader is called to read data and finds
-// that the output buffer is empty but that there is a pending overflow
-// entry, the reader will return a synthesized record for the pending
-// overflow entry.
-//
-// Only the writer can create or add to a pending overflow entry, but
-// either the reader or the writer can clear the pending overflow entry.
-// A pending overflow entry is indicated by the low 32 bits of 'overflow'
-// holding the number of discarded writes, and overflowTime holding the
-// time of the first discarded write. The high 32 bits of 'overflow'
-// increment each time the low 32 bits transition from zero to non-zero
-// or vice versa. This sequence number avoids ABA problems in the use of
-// compare-and-swap to coordinate between reader and writer.
-// The overflowTime is only written when the low 32 bits of overflow are
-// zero, that is, only when there is no pending overflow entry, in
-// preparation for creating a new one. The reader can therefore fetch and
-// clear the entry atomically using
-//
-//	for {
-//		overflow = load(&b.overflow)
-//		if uint32(overflow) == 0 {
-//			// no pending entry
-//			break
-//		}
-//		time = load(&b.overflowTime)
-//		if cas(&b.overflow, overflow, ((overflow>>32)+1)<<32) {
-//			// pending entry cleared
-//			break
-//		}
-//	}
-//	if uint32(overflow) > 0 {
-//		emit entry for uint32(overflow), time
-//	}
-//
-type profBuf struct {
-	// accessed atomically
-	r, w         profAtomic
-	overflow     uint64
-	overflowTime uint64
-	eof          uint32
-
-	// immutable (excluding slice content)
-	hdrsize uintptr
-	data    []uint64
-	tags    []unsafe.Pointer
-
-	// owned by reader
-	rNext       profIndex
-	overflowBuf []uint64 // for use by reader to return overflow record
-	wait        note
-}
-
-// A profAtomic is the atomically-accessed word holding a profIndex.
-type profAtomic uint64
-
-// A profIndex is the packet tag and data counts and flags bits, described above.
-type profIndex uint64
-
-const (
-	profReaderSleeping profIndex = 1 << 32 // reader is sleeping and must be woken up
-	profWriteExtra     profIndex = 1 << 33 // overflow or eof waiting
-)
-
-func (x *profAtomic) load() profIndex {
-	return profIndex(atomic.Load64((*uint64)(x)))
-}
-
-func (x *profAtomic) store(new profIndex) {
-	atomic.Store64((*uint64)(x), uint64(new))
-}
-
-func (x *profAtomic) cas(old, new profIndex) bool {
-	return atomic.Cas64((*uint64)(x), uint64(old), uint64(new))
-}
-
-func (x profIndex) dataCount() uint32 {
-	return uint32(x)
-}
-
-func (x profIndex) tagCount() uint32 {
-	return uint32(x >> 34)
-}
-
-// countSub subtracts two counts obtained from profIndex.dataCount or profIndex.tagCount,
-// assuming that they are no more than 2^29 apart (guaranteed since they are never more than
-// len(data) or len(tags) apart, respectively).
-// tagCount wraps at 2^30, while dataCount wraps at 2^32.
-// This function works for both.
-func countSub(x, y uint32) int {
-	// x-y is 32-bit signed or 30-bit signed; sign-extend to 32 bits and convert to int.
-	return int(int32(x-y) << 2 >> 2)
-}
-
-// addCountsAndClearFlags returns the packed form of "x + (data, tag) - all flags".
-func (x profIndex) addCountsAndClearFlags(data, tag int) profIndex {
-	return profIndex((uint64(x)>>34+uint64(uint32(tag)<<2>>2))<<34 | uint64(uint32(x)+uint32(data)))
-}
-
-// hasOverflow reports whether b has any overflow records pending.
-func (b *profBuf) hasOverflow() bool {
-	return uint32(atomic.Load64(&b.overflow)) > 0
-}
-
-// takeOverflow consumes the pending overflow records, returning the overflow count
-// and the time of the first overflow.
-// When called by the reader, it is racing against incrementOverflow.
-func (b *profBuf) takeOverflow() (count uint32, time uint64) {
-	overflow := atomic.Load64(&b.overflow)
-	time = atomic.Load64(&b.overflowTime)
-	for {
-		count = uint32(overflow)
-		if count == 0 {
-			time = 0
-			break
-		}
-		// Increment generation, clear overflow count in low bits.
-		if atomic.Cas64(&b.overflow, overflow, ((overflow>>32)+1)<<32) {
-			break
-		}
-		overflow = atomic.Load64(&b.overflow)
-		time = atomic.Load64(&b.overflowTime)
-	}
-	return uint32(overflow), time
-}
-
-// incrementOverflow records a single overflow at time now.
-// It is racing against a possible takeOverflow in the reader.
-func (b *profBuf) incrementOverflow(now int64) {
-	for {
-		overflow := atomic.Load64(&b.overflow)
-
-		// Once we see b.overflow reach 0, it's stable: no one else is changing it underfoot.
-		// We need to set overflowTime if we're incrementing b.overflow from 0.
-		if uint32(overflow) == 0 {
-			// Store overflowTime first so it's always available when overflow != 0.
-			atomic.Store64(&b.overflowTime, uint64(now))
-			atomic.Store64(&b.overflow, (((overflow>>32)+1)<<32)+1)
-			break
-		}
-		// Otherwise we're racing to increment against reader
-		// who wants to set b.overflow to 0.
-		// Out of paranoia, leave 2³²-1 a sticky overflow value,
-		// to avoid wrapping around. Extremely unlikely.
-		if int32(overflow) == -1 {
-			break
-		}
-		if atomic.Cas64(&b.overflow, overflow, overflow+1) {
-			break
-		}
-	}
-}
-
-// newProfBuf returns a new profiling buffer with room for
-// a header of hdrsize words and a buffer of at least bufwords words.
-func newProfBuf(hdrsize, bufwords, tags int) *profBuf {
-	if min := 2 + hdrsize + 1; bufwords < min {
-		bufwords = min
-	}
-
-	// Buffer sizes must be power of two, so that we don't have to
-	// worry about uint32 wraparound changing the effective position
-	// within the buffers. We store 30 bits of count; limiting to 28
-	// gives us some room for intermediate calculations.
-	if bufwords >= 1<<28 || tags >= 1<<28 {
-		throw("newProfBuf: buffer too large")
-	}
-	var i int
-	for i = 1; i < bufwords; i <<= 1 {
-	}
-	bufwords = i
-	for i = 1; i < tags; i <<= 1 {
-	}
-	tags = i
-
-	b := new(profBuf)
-	b.hdrsize = uintptr(hdrsize)
-	b.data = make([]uint64, bufwords)
-	b.tags = make([]unsafe.Pointer, tags)
-	b.overflowBuf = make([]uint64, 2+b.hdrsize+1)
-	return b
-}
-
-// canWriteRecord reports whether the buffer has room
-// for a single contiguous record with a stack of length nstk.
-func (b *profBuf) canWriteRecord(nstk int) bool {
-	br := b.r.load()
-	bw := b.w.load()
-
-	// room for tag?
-	if countSub(br.tagCount(), bw.tagCount())+len(b.tags) < 1 {
-		return false
-	}
-
-	// room for data?
-	nd := countSub(br.dataCount(), bw.dataCount()) + len(b.data)
-	want := 2 + int(b.hdrsize) + nstk
-	i := int(bw.dataCount() % uint32(len(b.data)))
-	if i+want > len(b.data) {
-		// Can't fit in trailing fragment of slice.
-		// Skip over that and start over at beginning of slice.
-		nd -= len(b.data) - i
-	}
-	return nd >= want
-}
-
-// canWriteTwoRecords reports whether the buffer has room
-// for two records with stack lengths nstk1, nstk2, in that order.
-// Each record must be contiguous on its own, but the two
-// records need not be contiguous (one can be at the end of the buffer
-// and the other can wrap around and start at the beginning of the buffer).
-func (b *profBuf) canWriteTwoRecords(nstk1, nstk2 int) bool {
-	br := b.r.load()
-	bw := b.w.load()
-
-	// room for tag?
-	if countSub(br.tagCount(), bw.tagCount())+len(b.tags) < 2 {
-		return false
-	}
-
-	// room for data?
-	nd := countSub(br.dataCount(), bw.dataCount()) + len(b.data)
-
-	// first record
-	want := 2 + int(b.hdrsize) + nstk1
-	i := int(bw.dataCount() % uint32(len(b.data)))
-	if i+want > len(b.data) {
-		// Can't fit in trailing fragment of slice.
-		// Skip over that and start over at beginning of slice.
-		nd -= len(b.data) - i
-		i = 0
-	}
-	i += want
-	nd -= want
-
-	// second record
-	want = 2 + int(b.hdrsize) + nstk2
-	if i+want > len(b.data) {
-		// Can't fit in trailing fragment of slice.
-		// Skip over that and start over at beginning of slice.
-		nd -= len(b.data) - i
-		i = 0
-	}
-	return nd >= want
-}
-
-// write writes an entry to the profiling buffer b.
-// The entry begins with a fixed hdr, which must have
-// length b.hdrsize, followed by a variable-sized stack
-// and a single tag pointer *tagPtr (or nil if tagPtr is nil).
-// No write barriers allowed because this might be called from a signal handler.
-func (b *profBuf) write(tagPtr *unsafe.Pointer, now int64, hdr []uint64, stk []uintptr) {
-	if b == nil {
-		return
-	}
-	if len(hdr) > int(b.hdrsize) {
-		throw("misuse of profBuf.write")
-	}
-
-	if hasOverflow := b.hasOverflow(); hasOverflow && b.canWriteTwoRecords(1, len(stk)) {
-		// Room for both an overflow record and the one being written.
-		// Write the overflow record if the reader hasn't gotten to it yet.
-		// Only racing against reader, not other writers.
-		count, time := b.takeOverflow()
-		if count > 0 {
-			var stk [1]uintptr
-			stk[0] = uintptr(count)
-			b.write(nil, int64(time), nil, stk[:])
-		}
-	} else if hasOverflow || !b.canWriteRecord(len(stk)) {
-		// Pending overflow without room to write overflow and new records
-		// or no overflow but also no room for new record.
-		b.incrementOverflow(now)
-		b.wakeupExtra()
-		return
-	}
-
-	// There's room: write the record.
-	br := b.r.load()
-	bw := b.w.load()
-
-	// Profiling tag
-	//
-	// The tag is a pointer, but we can't run a write barrier here.
-	// We have interrupted the OS-level execution of gp, but the
-	// runtime still sees gp as executing. In effect, we are running
-	// in place of the real gp. Since gp is the only goroutine that
-	// can overwrite gp.labels, the value of gp.labels is stable during
-	// this signal handler: it will still be reachable from gp when
-	// we finish executing. If a GC is in progress right now, it must
-	// keep gp.labels alive, because gp.labels is reachable from gp.
-	// If gp were to overwrite gp.labels, the deletion barrier would
-	// still shade that pointer, which would preserve it for the
-	// in-progress GC, so all is well. Any future GC will see the
-	// value we copied when scanning b.tags (heap-allocated).
-	// We arrange that the store here is always overwriting a nil,
-	// so there is no need for a deletion barrier on b.tags[wt].
-	wt := int(bw.tagCount() % uint32(len(b.tags)))
-	if tagPtr != nil {
-		*(*uintptr)(unsafe.Pointer(&b.tags[wt])) = uintptr(unsafe.Pointer(*tagPtr))
-	}
-
-	// Main record.
-	// It has to fit in a contiguous section of the slice, so if it doesn't fit at the end,
-	// leave a rewind marker (0) and start over at the beginning of the slice.
-	wd := int(bw.dataCount() % uint32(len(b.data)))
-	nd := countSub(br.dataCount(), bw.dataCount()) + len(b.data)
-	skip := 0
-	if wd+2+int(b.hdrsize)+len(stk) > len(b.data) {
-		b.data[wd] = 0
-		skip = len(b.data) - wd
-		nd -= skip
-		wd = 0
-	}
-	data := b.data[wd:]
-	data[0] = uint64(2 + b.hdrsize + uintptr(len(stk))) // length
-	data[1] = uint64(now)                               // time stamp
-	// header, zero-padded
-	i := uintptr(copy(data[2:2+b.hdrsize], hdr))
-	for ; i < b.hdrsize; i++ {
-		data[2+i] = 0
-	}
-	for i, pc := range stk {
-		data[2+b.hdrsize+uintptr(i)] = uint64(pc)
-	}
-
-	for {
-		// Commit write.
-		// Racing with reader setting flag bits in b.w, to avoid lost wakeups.
-		old := b.w.load()
-		new := old.addCountsAndClearFlags(skip+2+len(stk)+int(b.hdrsize), 1)
-		if !b.w.cas(old, new) {
-			continue
-		}
-		// If there was a reader, wake it up.
-		if old&profReaderSleeping != 0 {
-			notewakeup(&b.wait)
-		}
-		break
-	}
-}
-
-// close signals that there will be no more writes on the buffer.
-// Once all the data has been read from the buffer, reads will return eof=true.
-func (b *profBuf) close() {
-	if atomic.Load(&b.eof) > 0 {
-		throw("runtime: profBuf already closed")
-	}
-	atomic.Store(&b.eof, 1)
-	b.wakeupExtra()
-}
-
-// wakeupExtra must be called after setting one of the "extra"
-// atomic fields b.overflow or b.eof.
-// It records the change in b.w and wakes up the reader if needed.
-func (b *profBuf) wakeupExtra() {
-	for {
-		old := b.w.load()
-		new := old | profWriteExtra
-		if !b.w.cas(old, new) {
-			continue
-		}
-		if old&profReaderSleeping != 0 {
-			notewakeup(&b.wait)
-		}
-		break
-	}
-}
-
-// profBufReadMode specifies whether to block when no data is available to read.
-type profBufReadMode int
-
-const (
-	profBufBlocking profBufReadMode = iota
-	profBufNonBlocking
-)
-
-var overflowTag [1]unsafe.Pointer // always nil
-
-func (b *profBuf) read(mode profBufReadMode) (data []uint64, tags []unsafe.Pointer, eof bool) {
-	if b == nil {
-		return nil, nil, true
-	}
-
-	br := b.rNext
-
-	// Commit previous read, returning that part of the ring to the writer.
-	// First clear tags that have now been read, both to avoid holding
-	// up the memory they point at for longer than necessary
-	// and so that b.write can assume it is always overwriting
-	// nil tag entries (see comment in b.write).
-	rPrev := b.r.load()
-	if rPrev != br {
-		ntag := countSub(br.tagCount(), rPrev.tagCount())
-		ti := int(rPrev.tagCount() % uint32(len(b.tags)))
-		for i := 0; i < ntag; i++ {
-			b.tags[ti] = nil
-			if ti++; ti == len(b.tags) {
-				ti = 0
-			}
-		}
-		b.r.store(br)
-	}
-
-Read:
-	bw := b.w.load()
-	numData := countSub(bw.dataCount(), br.dataCount())
-	if numData == 0 {
-		if b.hasOverflow() {
-			// No data to read, but there is overflow to report.
-			// Racing with writer flushing b.overflow into a real record.
-			count, time := b.takeOverflow()
-			if count == 0 {
-				// Lost the race, go around again.
-				goto Read
-			}
-			// Won the race, report overflow.
-			dst := b.overflowBuf
-			dst[0] = uint64(2 + b.hdrsize + 1)
-			dst[1] = uint64(time)
-			for i := uintptr(0); i < b.hdrsize; i++ {
-				dst[2+i] = 0
-			}
-			dst[2+b.hdrsize] = uint64(count)
-			return dst[:2+b.hdrsize+1], overflowTag[:1], false
-		}
-		if atomic.Load(&b.eof) > 0 {
-			// No data, no overflow, EOF set: done.
-			return nil, nil, true
-		}
-		if bw&profWriteExtra != 0 {
-			// Writer claims to have published extra information (overflow or eof).
-			// Attempt to clear notification and then check again.
-			// If we fail to clear the notification it means b.w changed,
-			// so we still need to check again.
-			b.w.cas(bw, bw&^profWriteExtra)
-			goto Read
-		}
-
-		// Nothing to read right now.
-		// Return or sleep according to mode.
-		if mode == profBufNonBlocking {
-			return nil, nil, false
-		}
-		if !b.w.cas(bw, bw|profReaderSleeping) {
-			goto Read
-		}
-		// Committed to sleeping.
-		notetsleepg(&b.wait, -1)
-		noteclear(&b.wait)
-		goto Read
-	}
-	data = b.data[br.dataCount()%uint32(len(b.data)):]
-	if len(data) > numData {
-		data = data[:numData]
-	} else {
-		numData -= len(data) // available in case of wraparound
-	}
-	skip := 0
-	if data[0] == 0 {
-		// Wraparound record. Go back to the beginning of the ring.
-		skip = len(data)
-		data = b.data
-		if len(data) > numData {
-			data = data[:numData]
-		}
-	}
-
-	ntag := countSub(bw.tagCount(), br.tagCount())
-	if ntag == 0 {
-		throw("runtime: malformed profBuf buffer - tag and data out of sync")
-	}
-	tags = b.tags[br.tagCount()%uint32(len(b.tags)):]
-	if len(tags) > ntag {
-		tags = tags[:ntag]
-	}
-
-	// Count out whole data records until either data or tags is done.
-	// They are always in sync in the buffer, but due to an end-of-slice
-	// wraparound we might need to stop early and return the rest
-	// in the next call.
-	di := 0
-	ti := 0
-	for di < len(data) && data[di] != 0 && ti < len(tags) {
-		if uintptr(di)+uintptr(data[di]) > uintptr(len(data)) {
-			throw("runtime: malformed profBuf buffer - invalid size")
-		}
-		di += int(data[di])
-		ti++
-	}
-
-	// Remember how much we returned, to commit read on next call.
-	b.rNext = br.addCountsAndClearFlags(skip+di, ti)
-
-	if raceenabled {
-		// Match racereleasemerge in runtime_setProfLabel,
-		// so that the setting of the labels in runtime_setProfLabel
-		// is treated as happening before any use of the labels
-		// by our caller. The synchronization on labelSync itself is a fiction
-		// for the race detector. The actual synchronization is handled
-		// by the fact that the signal handler only reads from the current
-		// goroutine and uses atomics to write the updated queue indices,
-		// and then the read-out from the signal handler buffer uses
-		// atomics to read those queue indices.
-		raceacquire(unsafe.Pointer(&labelSync))
-	}
-
-	return data[:di], tags[:ti], false
-}
diff --git a/contrib/go/_std_1.18/src/runtime/runtime.go b/contrib/go/_std_1.18/src/runtime/runtime.go
deleted file mode 100644
index 33ecc260dd..0000000000
--- a/contrib/go/_std_1.18/src/runtime/runtime.go
+++ /dev/null
@@ -1,65 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"runtime/internal/atomic"
-	_ "unsafe" // for go:linkname
-)
-
-//go:generate go run wincallback.go
-//go:generate go run mkduff.go
-//go:generate go run mkfastlog2table.go
-
-var ticks struct {
-	lock mutex
-	pad  uint32 // ensure 8-byte alignment of val on 386
-	val  uint64
-}
-
-// Note: Called by runtime/pprof in addition to runtime code.
-func tickspersecond() int64 {
-	r := int64(atomic.Load64(&ticks.val))
-	if r != 0 {
-		return r
-	}
-	lock(&ticks.lock)
-	r = int64(ticks.val)
-	if r == 0 {
-		t0 := nanotime()
-		c0 := cputicks()
-		usleep(100 * 1000)
-		t1 := nanotime()
-		c1 := cputicks()
-		if t1 == t0 {
-			t1++
-		}
-		r = (c1 - c0) * 1000 * 1000 * 1000 / (t1 - t0)
-		if r == 0 {
-			r++
-		}
-		atomic.Store64(&ticks.val, uint64(r))
-	}
-	unlock(&ticks.lock)
-	return r
-}
-
-var envs []string
-var argslice []string
-
-//go:linkname syscall_runtime_envs syscall.runtime_envs
-func syscall_runtime_envs() []string { return append([]string{}, envs...) }
-
-//go:linkname syscall_Getpagesize syscall.Getpagesize
-func syscall_Getpagesize() int { return int(physPageSize) }
-
-//go:linkname os_runtime_args os.runtime_args
-func os_runtime_args() []string { return append([]string{}, argslice...) }
-
-//go:linkname syscall_Exit syscall.Exit
-//go:nosplit
-func syscall_Exit(code int) {
-	exit(int32(code))
-}
diff --git a/contrib/go/_std_1.18/src/runtime/runtime1.go b/contrib/go/_std_1.18/src/runtime/runtime1.go
deleted file mode 100644
index 65e1e0eebc..0000000000
--- a/contrib/go/_std_1.18/src/runtime/runtime1.go
+++ /dev/null
@@ -1,544 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"internal/bytealg"
-	"internal/goarch"
-	"runtime/internal/atomic"
-	"unsafe"
-)
-
-// Keep a cached value to make gotraceback fast,
-// since we call it on every call to gentraceback.
-// The cached value is a uint32 in which the low bits
-// are the "crash" and "all" settings and the remaining
-// bits are the traceback value (0 off, 1 on, 2 include system).
-const (
-	tracebackCrash = 1 << iota
-	tracebackAll
-	tracebackShift = iota
-)
-
-var traceback_cache uint32 = 2 << tracebackShift
-var traceback_env uint32
-
-// gotraceback returns the current traceback settings.
-//
-// If level is 0, suppress all tracebacks.
-// If level is 1, show tracebacks, but exclude runtime frames.
-// If level is 2, show tracebacks including runtime frames.
-// If all is set, print all goroutine stacks. Otherwise, print just the current goroutine.
-// If crash is set, crash (core dump, etc) after tracebacking.
-//
-//go:nosplit
-func gotraceback() (level int32, all, crash bool) {
-	_g_ := getg()
-	t := atomic.Load(&traceback_cache)
-	crash = t&tracebackCrash != 0
-	all = _g_.m.throwing > 0 || t&tracebackAll != 0
-	if _g_.m.traceback != 0 {
-		level = int32(_g_.m.traceback)
-	} else {
-		level = int32(t >> tracebackShift)
-	}
-	return
-}
-
-var (
-	argc int32
-	argv **byte
-)
-
-// nosplit for use in linux startup sysargs
-//go:nosplit
-func argv_index(argv **byte, i int32) *byte {
-	return *(**byte)(add(unsafe.Pointer(argv), uintptr(i)*goarch.PtrSize))
-}
-
-func args(c int32, v **byte) {
-	argc = c
-	argv = v
-	sysargs(c, v)
-}
-
-func goargs() {
-	if GOOS == "windows" {
-		return
-	}
-	argslice = make([]string, argc)
-	for i := int32(0); i < argc; i++ {
-		argslice[i] = gostringnocopy(argv_index(argv, i))
-	}
-}
-
-func goenvs_unix() {
-	// TODO(austin): ppc64 in dynamic linking mode doesn't
-	// guarantee env[] will immediately follow argv. Might cause
-	// problems.
-	n := int32(0)
-	for argv_index(argv, argc+1+n) != nil {
-		n++
-	}
-
-	envs = make([]string, n)
-	for i := int32(0); i < n; i++ {
-		envs[i] = gostring(argv_index(argv, argc+1+i))
-	}
-}
-
-func environ() []string {
-	return envs
-}
-
-// TODO: These should be locals in testAtomic64, but we don't 8-byte
-// align stack variables on 386.
-var test_z64, test_x64 uint64
-
-func testAtomic64() {
-	test_z64 = 42
-	test_x64 = 0
-	if atomic.Cas64(&test_z64, test_x64, 1) {
-		throw("cas64 failed")
-	}
-	if test_x64 != 0 {
-		throw("cas64 failed")
-	}
-	test_x64 = 42
-	if !atomic.Cas64(&test_z64, test_x64, 1) {
-		throw("cas64 failed")
-	}
-	if test_x64 != 42 || test_z64 != 1 {
-		throw("cas64 failed")
-	}
-	if atomic.Load64(&test_z64) != 1 {
-		throw("load64 failed")
-	}
-	atomic.Store64(&test_z64, (1<<40)+1)
-	if atomic.Load64(&test_z64) != (1<<40)+1 {
-		throw("store64 failed")
-	}
-	if atomic.Xadd64(&test_z64, (1<<40)+1) != (2<<40)+2 {
-		throw("xadd64 failed")
-	}
-	if atomic.Load64(&test_z64) != (2<<40)+2 {
-		throw("xadd64 failed")
-	}
-	if atomic.Xchg64(&test_z64, (3<<40)+3) != (2<<40)+2 {
-		throw("xchg64 failed")
-	}
-	if atomic.Load64(&test_z64) != (3<<40)+3 {
-		throw("xchg64 failed")
-	}
-}
-
-func check() {
-	var (
-		a     int8
-		b     uint8
-		c     int16
-		d     uint16
-		e     int32
-		f     uint32
-		g     int64
-		h     uint64
-		i, i1 float32
-		j, j1 float64
-		k     unsafe.Pointer
-		l     *uint16
-		m     [4]byte
-	)
-	type x1t struct {
-		x uint8
-	}
-	type y1t struct {
-		x1 x1t
-		y  uint8
-	}
-	var x1 x1t
-	var y1 y1t
-
-	if unsafe.Sizeof(a) != 1 {
-		throw("bad a")
-	}
-	if unsafe.Sizeof(b) != 1 {
-		throw("bad b")
-	}
-	if unsafe.Sizeof(c) != 2 {
-		throw("bad c")
-	}
-	if unsafe.Sizeof(d) != 2 {
-		throw("bad d")
-	}
-	if unsafe.Sizeof(e) != 4 {
-		throw("bad e")
-	}
-	if unsafe.Sizeof(f) != 4 {
-		throw("bad f")
-	}
-	if unsafe.Sizeof(g) != 8 {
-		throw("bad g")
-	}
-	if unsafe.Sizeof(h) != 8 {
-		throw("bad h")
-	}
-	if unsafe.Sizeof(i) != 4 {
-		throw("bad i")
-	}
-	if unsafe.Sizeof(j) != 8 {
-		throw("bad j")
-	}
-	if unsafe.Sizeof(k) != goarch.PtrSize {
-		throw("bad k")
-	}
-	if unsafe.Sizeof(l) != goarch.PtrSize {
-		throw("bad l")
-	}
-	if unsafe.Sizeof(x1) != 1 {
-		throw("bad unsafe.Sizeof x1")
-	}
-	if unsafe.Offsetof(y1.y) != 1 {
-		throw("bad offsetof y1.y")
-	}
-	if unsafe.Sizeof(y1) != 2 {
-		throw("bad unsafe.Sizeof y1")
-	}
-
-	if timediv(12345*1000000000+54321, 1000000000, &e) != 12345 || e != 54321 {
-		throw("bad timediv")
-	}
-
-	var z uint32
-	z = 1
-	if !atomic.Cas(&z, 1, 2) {
-		throw("cas1")
-	}
-	if z != 2 {
-		throw("cas2")
-	}
-
-	z = 4
-	if atomic.Cas(&z, 5, 6) {
-		throw("cas3")
-	}
-	if z != 4 {
-		throw("cas4")
-	}
-
-	z = 0xffffffff
-	if !atomic.Cas(&z, 0xffffffff, 0xfffffffe) {
-		throw("cas5")
-	}
-	if z != 0xfffffffe {
-		throw("cas6")
-	}
-
-	m = [4]byte{1, 1, 1, 1}
-	atomic.Or8(&m[1], 0xf0)
-	if m[0] != 1 || m[1] != 0xf1 || m[2] != 1 || m[3] != 1 {
-		throw("atomicor8")
-	}
-
-	m = [4]byte{0xff, 0xff, 0xff, 0xff}
-	atomic.And8(&m[1], 0x1)
-	if m[0] != 0xff || m[1] != 0x1 || m[2] != 0xff || m[3] != 0xff {
-		throw("atomicand8")
-	}
-
-	*(*uint64)(unsafe.Pointer(&j)) = ^uint64(0)
-	if j == j {
-		throw("float64nan")
-	}
-	if !(j != j) {
-		throw("float64nan1")
-	}
-
-	*(*uint64)(unsafe.Pointer(&j1)) = ^uint64(1)
-	if j == j1 {
-		throw("float64nan2")
-	}
-	if !(j != j1) {
-		throw("float64nan3")
-	}
-
-	*(*uint32)(unsafe.Pointer(&i)) = ^uint32(0)
-	if i == i {
-		throw("float32nan")
-	}
-	if i == i {
-		throw("float32nan1")
-	}
-
-	*(*uint32)(unsafe.Pointer(&i1)) = ^uint32(1)
-	if i == i1 {
-		throw("float32nan2")
-	}
-	if i == i1 {
-		throw("float32nan3")
-	}
-
-	testAtomic64()
-
-	if _FixedStack != round2(_FixedStack) {
-		throw("FixedStack is not power-of-2")
-	}
-
-	if !checkASM() {
-		throw("assembly checks failed")
-	}
-}
-
-type dbgVar struct {
-	name  string
-	value *int32
-}
-
-// Holds variables parsed from GODEBUG env var,
-// except for "memprofilerate" since there is an
-// existing int var for that value, which may
-// already have an initial value.
-var debug struct {
-	cgocheck           int32
-	clobberfree        int32
-	efence             int32
-	gccheckmark        int32
-	gcpacertrace       int32
-	gcshrinkstackoff   int32
-	gcstoptheworld     int32
-	gctrace            int32
-	invalidptr         int32
-	madvdontneed       int32 // for Linux; issue 28466
-	scavtrace          int32
-	scheddetail        int32
-	schedtrace         int32
-	tracebackancestors int32
-	asyncpreemptoff    int32
-	harddecommit       int32
-
-	// debug.malloc is used as a combined debug check
-	// in the malloc function and should be set
-	// if any of the below debug options is != 0.
-	malloc         bool
-	allocfreetrace int32
-	inittrace      int32
-	sbrk           int32
-}
-
-var dbgvars = []dbgVar{
-	{"allocfreetrace", &debug.allocfreetrace},
-	{"clobberfree", &debug.clobberfree},
-	{"cgocheck", &debug.cgocheck},
-	{"efence", &debug.efence},
-	{"gccheckmark", &debug.gccheckmark},
-	{"gcpacertrace", &debug.gcpacertrace},
-	{"gcshrinkstackoff", &debug.gcshrinkstackoff},
-	{"gcstoptheworld", &debug.gcstoptheworld},
-	{"gctrace", &debug.gctrace},
-	{"invalidptr", &debug.invalidptr},
-	{"madvdontneed", &debug.madvdontneed},
-	{"sbrk", &debug.sbrk},
-	{"scavtrace", &debug.scavtrace},
-	{"scheddetail", &debug.scheddetail},
-	{"schedtrace", &debug.schedtrace},
-	{"tracebackancestors", &debug.tracebackancestors},
-	{"asyncpreemptoff", &debug.asyncpreemptoff},
-	{"inittrace", &debug.inittrace},
-	{"harddecommit", &debug.harddecommit},
-}
-
-func parsedebugvars() {
-	// defaults
-	debug.cgocheck = 1
-	debug.invalidptr = 1
-	if GOOS == "linux" {
-		// On Linux, MADV_FREE is faster than MADV_DONTNEED,
-		// but doesn't affect many of the statistics that
-		// MADV_DONTNEED does until the memory is actually
-		// reclaimed. This generally leads to poor user
-		// experience, like confusing stats in top and other
-		// monitoring tools; and bad integration with
-		// management systems that respond to memory usage.
-		// Hence, default to MADV_DONTNEED.
-		debug.madvdontneed = 1
-	}
-
-	for p := gogetenv("GODEBUG"); p != ""; {
-		field := ""
-		i := bytealg.IndexByteString(p, ',')
-		if i < 0 {
-			field, p = p, ""
-		} else {
-			field, p = p[:i], p[i+1:]
-		}
-		i = bytealg.IndexByteString(field, '=')
-		if i < 0 {
-			continue
-		}
-		key, value := field[:i], field[i+1:]
-
-		// Update MemProfileRate directly here since it
-		// is int, not int32, and should only be updated
-		// if specified in GODEBUG.
-		if key == "memprofilerate" {
-			if n, ok := atoi(value); ok {
-				MemProfileRate = n
-			}
-		} else {
-			for _, v := range dbgvars {
-				if v.name == key {
-					if n, ok := atoi32(value); ok {
-						*v.value = n
-					}
-				}
-			}
-		}
-	}
-
-	debug.malloc = (debug.allocfreetrace | debug.inittrace | debug.sbrk) != 0
-
-	setTraceback(gogetenv("GOTRACEBACK"))
-	traceback_env = traceback_cache
-}
-
-//go:linkname setTraceback runtime/debug.SetTraceback
-func setTraceback(level string) {
-	var t uint32
-	switch level {
-	case "none":
-		t = 0
-	case "single", "":
-		t = 1 << tracebackShift
-	case "all":
-		t = 1<<tracebackShift | tracebackAll
-	case "system":
-		t = 2<<tracebackShift | tracebackAll
-	case "crash":
-		t = 2<<tracebackShift | tracebackAll | tracebackCrash
-	default:
-		t = tracebackAll
-		if n, ok := atoi(level); ok && n == int(uint32(n)) {
-			t |= uint32(n) << tracebackShift
-		}
-	}
-	// when C owns the process, simply exit'ing the process on fatal errors
-	// and panics is surprising. Be louder and abort instead.
-	if islibrary || isarchive {
-		t |= tracebackCrash
-	}
-
-	t |= traceback_env
-
-	atomic.Store(&traceback_cache, t)
-}
-
-// Poor mans 64-bit division.
-// This is a very special function, do not use it if you are not sure what you are doing.
-// int64 division is lowered into _divv() call on 386, which does not fit into nosplit functions.
-// Handles overflow in a time-specific manner.
-// This keeps us within no-split stack limits on 32-bit processors.
-//go:nosplit
-func timediv(v int64, div int32, rem *int32) int32 {
-	res := int32(0)
-	for bit := 30; bit >= 0; bit-- {
-		if v >= int64(div)<<uint(bit) {
-			v = v - (int64(div) << uint(bit))
-			// Before this for loop, res was 0, thus all these
-			// power of 2 increments are now just bitsets.
-			res |= 1 << uint(bit)
-		}
-	}
-	if v >= int64(div) {
-		if rem != nil {
-			*rem = 0
-		}
-		return 0x7fffffff
-	}
-	if rem != nil {
-		*rem = int32(v)
-	}
-	return res
-}
-
-// Helpers for Go. Must be NOSPLIT, must only call NOSPLIT functions, and must not block.
-
-//go:nosplit
-func acquirem() *m {
-	_g_ := getg()
-	_g_.m.locks++
-	return _g_.m
-}
-
-//go:nosplit
-func releasem(mp *m) {
-	_g_ := getg()
-	mp.locks--
-	if mp.locks == 0 && _g_.preempt {
-		// restore the preemption request in case we've cleared it in newstack
-		_g_.stackguard0 = stackPreempt
-	}
-}
-
-//go:linkname reflect_typelinks reflect.typelinks
-func reflect_typelinks() ([]unsafe.Pointer, [][]int32) {
-	modules := activeModules()
-	sections := []unsafe.Pointer{unsafe.Pointer(modules[0].types)}
-	ret := [][]int32{modules[0].typelinks}
-	for _, md := range modules[1:] {
-		sections = append(sections, unsafe.Pointer(md.types))
-		ret = append(ret, md.typelinks)
-	}
-	return sections, ret
-}
-
-// reflect_resolveNameOff resolves a name offset from a base pointer.
-//go:linkname reflect_resolveNameOff reflect.resolveNameOff
-func reflect_resolveNameOff(ptrInModule unsafe.Pointer, off int32) unsafe.Pointer {
-	return unsafe.Pointer(resolveNameOff(ptrInModule, nameOff(off)).bytes)
-}
-
-// reflect_resolveTypeOff resolves an *rtype offset from a base type.
-//go:linkname reflect_resolveTypeOff reflect.resolveTypeOff
-func reflect_resolveTypeOff(rtype unsafe.Pointer, off int32) unsafe.Pointer {
-	return unsafe.Pointer((*_type)(rtype).typeOff(typeOff(off)))
-}
-
-// reflect_resolveTextOff resolves a function pointer offset from a base type.
-//go:linkname reflect_resolveTextOff reflect.resolveTextOff
-func reflect_resolveTextOff(rtype unsafe.Pointer, off int32) unsafe.Pointer {
-	return (*_type)(rtype).textOff(textOff(off))
-
-}
-
-// reflectlite_resolveNameOff resolves a name offset from a base pointer.
-//go:linkname reflectlite_resolveNameOff internal/reflectlite.resolveNameOff
-func reflectlite_resolveNameOff(ptrInModule unsafe.Pointer, off int32) unsafe.Pointer {
-	return unsafe.Pointer(resolveNameOff(ptrInModule, nameOff(off)).bytes)
-}
-
-// reflectlite_resolveTypeOff resolves an *rtype offset from a base type.
-//go:linkname reflectlite_resolveTypeOff internal/reflectlite.resolveTypeOff
-func reflectlite_resolveTypeOff(rtype unsafe.Pointer, off int32) unsafe.Pointer {
-	return unsafe.Pointer((*_type)(rtype).typeOff(typeOff(off)))
-}
-
-// reflect_addReflectOff adds a pointer to the reflection offset lookup map.
-//go:linkname reflect_addReflectOff reflect.addReflectOff
-func reflect_addReflectOff(ptr unsafe.Pointer) int32 {
-	reflectOffsLock()
-	if reflectOffs.m == nil {
-		reflectOffs.m = make(map[int32]unsafe.Pointer)
-		reflectOffs.minv = make(map[unsafe.Pointer]int32)
-		reflectOffs.next = -1
-	}
-	id, found := reflectOffs.minv[ptr]
-	if !found {
-		id = reflectOffs.next
-		reflectOffs.next-- // use negative offsets as IDs to aid debugging
-		reflectOffs.m[id] = ptr
-		reflectOffs.minv[ptr] = id
-	}
-	reflectOffsUnlock()
-	return id
-}
diff --git a/contrib/go/_std_1.18/src/runtime/runtime2.go b/contrib/go/_std_1.18/src/runtime/runtime2.go
deleted file mode 100644
index b40045e4a5..0000000000
--- a/contrib/go/_std_1.18/src/runtime/runtime2.go
+++ /dev/null
@@ -1,1134 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"internal/goarch"
-	"runtime/internal/atomic"
-	"unsafe"
-)
-
-// defined constants
-const (
-	// G status
-	//
-	// Beyond indicating the general state of a G, the G status
-	// acts like a lock on the goroutine's stack (and hence its
-	// ability to execute user code).
-	//
-	// If you add to this list, add to the list
-	// of "okay during garbage collection" status
-	// in mgcmark.go too.
-	//
-	// TODO(austin): The _Gscan bit could be much lighter-weight.
-	// For example, we could choose not to run _Gscanrunnable
-	// goroutines found in the run queue, rather than CAS-looping
-	// until they become _Grunnable. And transitions like
-	// _Gscanwaiting -> _Gscanrunnable are actually okay because
-	// they don't affect stack ownership.
-
-	// _Gidle means this goroutine was just allocated and has not
-	// yet been initialized.
-	_Gidle = iota // 0
-
-	// _Grunnable means this goroutine is on a run queue. It is
-	// not currently executing user code. The stack is not owned.
-	_Grunnable // 1
-
-	// _Grunning means this goroutine may execute user code. The
-	// stack is owned by this goroutine. It is not on a run queue.
-	// It is assigned an M and a P (g.m and g.m.p are valid).
-	_Grunning // 2
-
-	// _Gsyscall means this goroutine is executing a system call.
-	// It is not executing user code. The stack is owned by this
-	// goroutine. It is not on a run queue. It is assigned an M.
-	_Gsyscall // 3
-
-	// _Gwaiting means this goroutine is blocked in the runtime.
-	// It is not executing user code. It is not on a run queue,
-	// but should be recorded somewhere (e.g., a channel wait
-	// queue) so it can be ready()d when necessary. The stack is
-	// not owned *except* that a channel operation may read or
-	// write parts of the stack under the appropriate channel
-	// lock. Otherwise, it is not safe to access the stack after a
-	// goroutine enters _Gwaiting (e.g., it may get moved).
-	_Gwaiting // 4
-
-	// _Gmoribund_unused is currently unused, but hardcoded in gdb
-	// scripts.
-	_Gmoribund_unused // 5
-
-	// _Gdead means this goroutine is currently unused. It may be
-	// just exited, on a free list, or just being initialized. It
-	// is not executing user code. It may or may not have a stack
-	// allocated. The G and its stack (if any) are owned by the M
-	// that is exiting the G or that obtained the G from the free
-	// list.
-	_Gdead // 6
-
-	// _Genqueue_unused is currently unused.
-	_Genqueue_unused // 7
-
-	// _Gcopystack means this goroutine's stack is being moved. It
-	// is not executing user code and is not on a run queue. The
-	// stack is owned by the goroutine that put it in _Gcopystack.
-	_Gcopystack // 8
-
-	// _Gpreempted means this goroutine stopped itself for a
-	// suspendG preemption. It is like _Gwaiting, but nothing is
-	// yet responsible for ready()ing it. Some suspendG must CAS
-	// the status to _Gwaiting to take responsibility for
-	// ready()ing this G.
-	_Gpreempted // 9
-
-	// _Gscan combined with one of the above states other than
-	// _Grunning indicates that GC is scanning the stack. The
-	// goroutine is not executing user code and the stack is owned
-	// by the goroutine that set the _Gscan bit.
-	//
-	// _Gscanrunning is different: it is used to briefly block
-	// state transitions while GC signals the G to scan its own
-	// stack. This is otherwise like _Grunning.
-	//
-	// atomicstatus&~Gscan gives the state the goroutine will
-	// return to when the scan completes.
-	_Gscan          = 0x1000
-	_Gscanrunnable  = _Gscan + _Grunnable  // 0x1001
-	_Gscanrunning   = _Gscan + _Grunning   // 0x1002
-	_Gscansyscall   = _Gscan + _Gsyscall   // 0x1003
-	_Gscanwaiting   = _Gscan + _Gwaiting   // 0x1004
-	_Gscanpreempted = _Gscan + _Gpreempted // 0x1009
-)
-
-const (
-	// P status
-
-	// _Pidle means a P is not being used to run user code or the
-	// scheduler. Typically, it's on the idle P list and available
-	// to the scheduler, but it may just be transitioning between
-	// other states.
-	//
-	// The P is owned by the idle list or by whatever is
-	// transitioning its state. Its run queue is empty.
-	_Pidle = iota
-
-	// _Prunning means a P is owned by an M and is being used to
-	// run user code or the scheduler. Only the M that owns this P
-	// is allowed to change the P's status from _Prunning. The M
-	// may transition the P to _Pidle (if it has no more work to
-	// do), _Psyscall (when entering a syscall), or _Pgcstop (to
-	// halt for the GC). The M may also hand ownership of the P
-	// off directly to another M (e.g., to schedule a locked G).
-	_Prunning
-
-	// _Psyscall means a P is not running user code. It has
-	// affinity to an M in a syscall but is not owned by it and
-	// may be stolen by another M. This is similar to _Pidle but
-	// uses lightweight transitions and maintains M affinity.
-	//
-	// Leaving _Psyscall must be done with a CAS, either to steal
-	// or retake the P. Note that there's an ABA hazard: even if
-	// an M successfully CASes its original P back to _Prunning
-	// after a syscall, it must understand the P may have been
-	// used by another M in the interim.
-	_Psyscall
-
-	// _Pgcstop means a P is halted for STW and owned by the M
-	// that stopped the world. The M that stopped the world
-	// continues to use its P, even in _Pgcstop. Transitioning
-	// from _Prunning to _Pgcstop causes an M to release its P and
-	// park.
-	//
-	// The P retains its run queue and startTheWorld will restart
-	// the scheduler on Ps with non-empty run queues.
-	_Pgcstop
-
-	// _Pdead means a P is no longer used (GOMAXPROCS shrank). We
-	// reuse Ps if GOMAXPROCS increases. A dead P is mostly
-	// stripped of its resources, though a few things remain
-	// (e.g., trace buffers).
-	_Pdead
-)
-
-// Mutual exclusion locks.  In the uncontended case,
-// as fast as spin locks (just a few user-level instructions),
-// but on the contention path they sleep in the kernel.
-// A zeroed Mutex is unlocked (no need to initialize each lock).
-// Initialization is helpful for static lock ranking, but not required.
-type mutex struct {
-	// Empty struct if lock ranking is disabled, otherwise includes the lock rank
-	lockRankStruct
-	// Futex-based impl treats it as uint32 key,
-	// while sema-based impl as M* waitm.
-	// Used to be a union, but unions break precise GC.
-	key uintptr
-}
-
-// sleep and wakeup on one-time events.
-// before any calls to notesleep or notewakeup,
-// must call noteclear to initialize the Note.
-// then, exactly one thread can call notesleep
-// and exactly one thread can call notewakeup (once).
-// once notewakeup has been called, the notesleep
-// will return.  future notesleep will return immediately.
-// subsequent noteclear must be called only after
-// previous notesleep has returned, e.g. it's disallowed
-// to call noteclear straight after notewakeup.
-//
-// notetsleep is like notesleep but wakes up after
-// a given number of nanoseconds even if the event
-// has not yet happened.  if a goroutine uses notetsleep to
-// wake up early, it must wait to call noteclear until it
-// can be sure that no other goroutine is calling
-// notewakeup.
-//
-// notesleep/notetsleep are generally called on g0,
-// notetsleepg is similar to notetsleep but is called on user g.
-type note struct {
-	// Futex-based impl treats it as uint32 key,
-	// while sema-based impl as M* waitm.
-	// Used to be a union, but unions break precise GC.
-	key uintptr
-}
-
-type funcval struct {
-	fn uintptr
-	// variable-size, fn-specific data here
-}
-
-type iface struct {
-	tab  *itab
-	data unsafe.Pointer
-}
-
-type eface struct {
-	_type *_type
-	data  unsafe.Pointer
-}
-
-func efaceOf(ep *any) *eface {
-	return (*eface)(unsafe.Pointer(ep))
-}
-
-// The guintptr, muintptr, and puintptr are all used to bypass write barriers.
-// It is particularly important to avoid write barriers when the current P has
-// been released, because the GC thinks the world is stopped, and an
-// unexpected write barrier would not be synchronized with the GC,
-// which can lead to a half-executed write barrier that has marked the object
-// but not queued it. If the GC skips the object and completes before the
-// queuing can occur, it will incorrectly free the object.
-//
-// We tried using special assignment functions invoked only when not
-// holding a running P, but then some updates to a particular memory
-// word went through write barriers and some did not. This breaks the
-// write barrier shadow checking mode, and it is also scary: better to have
-// a word that is completely ignored by the GC than to have one for which
-// only a few updates are ignored.
-//
-// Gs and Ps are always reachable via true pointers in the
-// allgs and allp lists or (during allocation before they reach those lists)
-// from stack variables.
-//
-// Ms are always reachable via true pointers either from allm or
-// freem. Unlike Gs and Ps we do free Ms, so it's important that
-// nothing ever hold an muintptr across a safe point.
-
-// A guintptr holds a goroutine pointer, but typed as a uintptr
-// to bypass write barriers. It is used in the Gobuf goroutine state
-// and in scheduling lists that are manipulated without a P.
-//
-// The Gobuf.g goroutine pointer is almost always updated by assembly code.
-// In one of the few places it is updated by Go code - func save - it must be
-// treated as a uintptr to avoid a write barrier being emitted at a bad time.
-// Instead of figuring out how to emit the write barriers missing in the
-// assembly manipulation, we change the type of the field to uintptr,
-// so that it does not require write barriers at all.
-//
-// Goroutine structs are published in the allg list and never freed.
-// That will keep the goroutine structs from being collected.
-// There is never a time that Gobuf.g's contain the only references
-// to a goroutine: the publishing of the goroutine in allg comes first.
-// Goroutine pointers are also kept in non-GC-visible places like TLS,
-// so I can't see them ever moving. If we did want to start moving data
-// in the GC, we'd need to allocate the goroutine structs from an
-// alternate arena. Using guintptr doesn't make that problem any worse.
-// Note that pollDesc.rg, pollDesc.wg also store g in uintptr form,
-// so they would need to be updated too if g's start moving.
-type guintptr uintptr
-
-//go:nosplit
-func (gp guintptr) ptr() *g { return (*g)(unsafe.Pointer(gp)) }
-
-//go:nosplit
-func (gp *guintptr) set(g *g) { *gp = guintptr(unsafe.Pointer(g)) }
-
-//go:nosplit
-func (gp *guintptr) cas(old, new guintptr) bool {
-	return atomic.Casuintptr((*uintptr)(unsafe.Pointer(gp)), uintptr(old), uintptr(new))
-}
-
-// setGNoWB performs *gp = new without a write barrier.
-// For times when it's impractical to use a guintptr.
-//go:nosplit
-//go:nowritebarrier
-func setGNoWB(gp **g, new *g) {
-	(*guintptr)(unsafe.Pointer(gp)).set(new)
-}
-
-type puintptr uintptr
-
-//go:nosplit
-func (pp puintptr) ptr() *p { return (*p)(unsafe.Pointer(pp)) }
-
-//go:nosplit
-func (pp *puintptr) set(p *p) { *pp = puintptr(unsafe.Pointer(p)) }
-
-// muintptr is a *m that is not tracked by the garbage collector.
-//
-// Because we do free Ms, there are some additional constrains on
-// muintptrs:
-//
-// 1. Never hold an muintptr locally across a safe point.
-//
-// 2. Any muintptr in the heap must be owned by the M itself so it can
-//    ensure it is not in use when the last true *m is released.
-type muintptr uintptr
-
-//go:nosplit
-func (mp muintptr) ptr() *m { return (*m)(unsafe.Pointer(mp)) }
-
-//go:nosplit
-func (mp *muintptr) set(m *m) { *mp = muintptr(unsafe.Pointer(m)) }
-
-// setMNoWB performs *mp = new without a write barrier.
-// For times when it's impractical to use an muintptr.
-//go:nosplit
-//go:nowritebarrier
-func setMNoWB(mp **m, new *m) {
-	(*muintptr)(unsafe.Pointer(mp)).set(new)
-}
-
-type gobuf struct {
-	// The offsets of sp, pc, and g are known to (hard-coded in) libmach.
-	//
-	// ctxt is unusual with respect to GC: it may be a
-	// heap-allocated funcval, so GC needs to track it, but it
-	// needs to be set and cleared from assembly, where it's
-	// difficult to have write barriers. However, ctxt is really a
-	// saved, live register, and we only ever exchange it between
-	// the real register and the gobuf. Hence, we treat it as a
-	// root during stack scanning, which means assembly that saves
-	// and restores it doesn't need write barriers. It's still
-	// typed as a pointer so that any other writes from Go get
-	// write barriers.
-	sp   uintptr
-	pc   uintptr
-	g    guintptr
-	ctxt unsafe.Pointer
-	ret  uintptr
-	lr   uintptr
-	bp   uintptr // for framepointer-enabled architectures
-}
-
-// sudog represents a g in a wait list, such as for sending/receiving
-// on a channel.
-//
-// sudog is necessary because the g ↔ synchronization object relation
-// is many-to-many. A g can be on many wait lists, so there may be
-// many sudogs for one g; and many gs may be waiting on the same
-// synchronization object, so there may be many sudogs for one object.
-//
-// sudogs are allocated from a special pool. Use acquireSudog and
-// releaseSudog to allocate and free them.
-type sudog struct {
-	// The following fields are protected by the hchan.lock of the
-	// channel this sudog is blocking on. shrinkstack depends on
-	// this for sudogs involved in channel ops.
-
-	g *g
-
-	next *sudog
-	prev *sudog
-	elem unsafe.Pointer // data element (may point to stack)
-
-	// The following fields are never accessed concurrently.
-	// For channels, waitlink is only accessed by g.
-	// For semaphores, all fields (including the ones above)
-	// are only accessed when holding a semaRoot lock.
-
-	acquiretime int64
-	releasetime int64
-	ticket      uint32
-
-	// isSelect indicates g is participating in a select, so
-	// g.selectDone must be CAS'd to win the wake-up race.
-	isSelect bool
-
-	// success indicates whether communication over channel c
-	// succeeded. It is true if the goroutine was awoken because a
-	// value was delivered over channel c, and false if awoken
-	// because c was closed.
-	success bool
-
-	parent   *sudog // semaRoot binary tree
-	waitlink *sudog // g.waiting list or semaRoot
-	waittail *sudog // semaRoot
-	c        *hchan // channel
-}
-
-type libcall struct {
-	fn   uintptr
-	n    uintptr // number of parameters
-	args uintptr // parameters
-	r1   uintptr // return values
-	r2   uintptr
-	err  uintptr // error number
-}
-
-// Stack describes a Go execution stack.
-// The bounds of the stack are exactly [lo, hi),
-// with no implicit data structures on either side.
-type stack struct {
-	lo uintptr
-	hi uintptr
-}
-
-// heldLockInfo gives info on a held lock and the rank of that lock
-type heldLockInfo struct {
-	lockAddr uintptr
-	rank     lockRank
-}
-
-type g struct {
-	// Stack parameters.
-	// stack describes the actual stack memory: [stack.lo, stack.hi).
-	// stackguard0 is the stack pointer compared in the Go stack growth prologue.
-	// It is stack.lo+StackGuard normally, but can be StackPreempt to trigger a preemption.
-	// stackguard1 is the stack pointer compared in the C stack growth prologue.
-	// It is stack.lo+StackGuard on g0 and gsignal stacks.
-	// It is ~0 on other goroutine stacks, to trigger a call to morestackc (and crash).
-	stack       stack   // offset known to runtime/cgo
-	stackguard0 uintptr // offset known to liblink
-	stackguard1 uintptr // offset known to liblink
-
-	_panic    *_panic // innermost panic - offset known to liblink
-	_defer    *_defer // innermost defer
-	m         *m      // current m; offset known to arm liblink
-	sched     gobuf
-	syscallsp uintptr // if status==Gsyscall, syscallsp = sched.sp to use during gc
-	syscallpc uintptr // if status==Gsyscall, syscallpc = sched.pc to use during gc
-	stktopsp  uintptr // expected sp at top of stack, to check in traceback
-	// param is a generic pointer parameter field used to pass
-	// values in particular contexts where other storage for the
-	// parameter would be difficult to find. It is currently used
-	// in three ways:
-	// 1. When a channel operation wakes up a blocked goroutine, it sets param to
-	//    point to the sudog of the completed blocking operation.
-	// 2. By gcAssistAlloc1 to signal back to its caller that the goroutine completed
-	//    the GC cycle. It is unsafe to do so in any other way, because the goroutine's
-	//    stack may have moved in the meantime.
-	// 3. By debugCallWrap to pass parameters to a new goroutine because allocating a
-	//    closure in the runtime is forbidden.
-	param        unsafe.Pointer
-	atomicstatus uint32
-	stackLock    uint32 // sigprof/scang lock; TODO: fold in to atomicstatus
-	goid         int64
-	schedlink    guintptr
-	waitsince    int64      // approx time when the g become blocked
-	waitreason   waitReason // if status==Gwaiting
-
-	preempt       bool // preemption signal, duplicates stackguard0 = stackpreempt
-	preemptStop   bool // transition to _Gpreempted on preemption; otherwise, just deschedule
-	preemptShrink bool // shrink stack at synchronous safe point
-
-	// asyncSafePoint is set if g is stopped at an asynchronous
-	// safe point. This means there are frames on the stack
-	// without precise pointer information.
-	asyncSafePoint bool
-
-	paniconfault bool // panic (instead of crash) on unexpected fault address
-	gcscandone   bool // g has scanned stack; protected by _Gscan bit in status
-	throwsplit   bool // must not split stack
-	// activeStackChans indicates that there are unlocked channels
-	// pointing into this goroutine's stack. If true, stack
-	// copying needs to acquire channel locks to protect these
-	// areas of the stack.
-	activeStackChans bool
-	// parkingOnChan indicates that the goroutine is about to
-	// park on a chansend or chanrecv. Used to signal an unsafe point
-	// for stack shrinking. It's a boolean value, but is updated atomically.
-	parkingOnChan uint8
-
-	raceignore     int8     // ignore race detection events
-	sysblocktraced bool     // StartTrace has emitted EvGoInSyscall about this goroutine
-	tracking       bool     // whether we're tracking this G for sched latency statistics
-	trackingSeq    uint8    // used to decide whether to track this G
-	runnableStamp  int64    // timestamp of when the G last became runnable, only used when tracking
-	runnableTime   int64    // the amount of time spent runnable, cleared when running, only used when tracking
-	sysexitticks   int64    // cputicks when syscall has returned (for tracing)
-	traceseq       uint64   // trace event sequencer
-	tracelastp     puintptr // last P emitted an event for this goroutine
-	lockedm        muintptr
-	sig            uint32
-	writebuf       []byte
-	sigcode0       uintptr
-	sigcode1       uintptr
-	sigpc          uintptr
-	gopc           uintptr         // pc of go statement that created this goroutine
-	ancestors      *[]ancestorInfo // ancestor information goroutine(s) that created this goroutine (only used if debug.tracebackancestors)
-	startpc        uintptr         // pc of goroutine function
-	racectx        uintptr
-	waiting        *sudog         // sudog structures this g is waiting on (that have a valid elem ptr); in lock order
-	cgoCtxt        []uintptr      // cgo traceback context
-	labels         unsafe.Pointer // profiler labels
-	timer          *timer         // cached timer for time.Sleep
-	selectDone     uint32         // are we participating in a select and did someone win the race?
-
-	// Per-G GC state
-
-	// gcAssistBytes is this G's GC assist credit in terms of
-	// bytes allocated. If this is positive, then the G has credit
-	// to allocate gcAssistBytes bytes without assisting. If this
-	// is negative, then the G must correct this by performing
-	// scan work. We track this in bytes to make it fast to update
-	// and check for debt in the malloc hot path. The assist ratio
-	// determines how this corresponds to scan work debt.
-	gcAssistBytes int64
-}
-
-// gTrackingPeriod is the number of transitions out of _Grunning between
-// latency tracking runs.
-const gTrackingPeriod = 8
-
-const (
-	// tlsSlots is the number of pointer-sized slots reserved for TLS on some platforms,
-	// like Windows.
-	tlsSlots = 6
-	tlsSize  = tlsSlots * goarch.PtrSize
-)
-
-type m struct {
-	g0      *g     // goroutine with scheduling stack
-	morebuf gobuf  // gobuf arg to morestack
-	divmod  uint32 // div/mod denominator for arm - known to liblink
-	_       uint32 // align next field to 8 bytes
-
-	// Fields not known to debuggers.
-	procid        uint64            // for debuggers, but offset not hard-coded
-	gsignal       *g                // signal-handling g
-	goSigStack    gsignalStack      // Go-allocated signal handling stack
-	sigmask       sigset            // storage for saved signal mask
-	tls           [tlsSlots]uintptr // thread-local storage (for x86 extern register)
-	mstartfn      func()
-	curg          *g       // current running goroutine
-	caughtsig     guintptr // goroutine running during fatal signal
-	p             puintptr // attached p for executing go code (nil if not executing go code)
-	nextp         puintptr
-	oldp          puintptr // the p that was attached before executing a syscall
-	id            int64
-	mallocing     int32
-	throwing      int32
-	preemptoff    string // if != "", keep curg running on this m
-	locks         int32
-	dying         int32
-	profilehz     int32
-	spinning      bool // m is out of work and is actively looking for work
-	blocked       bool // m is blocked on a note
-	newSigstack   bool // minit on C thread called sigaltstack
-	printlock     int8
-	incgo         bool   // m is executing a cgo call
-	freeWait      uint32 // if == 0, safe to free g0 and delete m (atomic)
-	fastrand      uint64
-	needextram    bool
-	traceback     uint8
-	ncgocall      uint64      // number of cgo calls in total
-	ncgo          int32       // number of cgo calls currently in progress
-	cgoCallersUse uint32      // if non-zero, cgoCallers in use temporarily
-	cgoCallers    *cgoCallers // cgo traceback if crashing in cgo call
-	park          note
-	alllink       *m // on allm
-	schedlink     muintptr
-	lockedg       guintptr
-	createstack   [32]uintptr // stack that created this thread.
-	lockedExt     uint32      // tracking for external LockOSThread
-	lockedInt     uint32      // tracking for internal lockOSThread
-	nextwaitm     muintptr    // next m waiting for lock
-	waitunlockf   func(*g, unsafe.Pointer) bool
-	waitlock      unsafe.Pointer
-	waittraceev   byte
-	waittraceskip int
-	startingtrace bool
-	syscalltick   uint32
-	freelink      *m // on sched.freem
-
-	// these are here because they are too large to be on the stack
-	// of low-level NOSPLIT functions.
-	libcall   libcall
-	libcallpc uintptr // for cpu profiler
-	libcallsp uintptr
-	libcallg  guintptr
-	syscall   libcall // stores syscall parameters on windows
-
-	vdsoSP uintptr // SP for traceback while in VDSO call (0 if not in call)
-	vdsoPC uintptr // PC for traceback while in VDSO call
-
-	// preemptGen counts the number of completed preemption
-	// signals. This is used to detect when a preemption is
-	// requested, but fails. Accessed atomically.
-	preemptGen uint32
-
-	// Whether this is a pending preemption signal on this M.
-	// Accessed atomically.
-	signalPending uint32
-
-	dlogPerM
-
-	mOS
-
-	// Up to 10 locks held by this m, maintained by the lock ranking code.
-	locksHeldLen int
-	locksHeld    [10]heldLockInfo
-}
-
-type p struct {
-	id          int32
-	status      uint32 // one of pidle/prunning/...
-	link        puintptr
-	schedtick   uint32     // incremented on every scheduler call
-	syscalltick uint32     // incremented on every system call
-	sysmontick  sysmontick // last tick observed by sysmon
-	m           muintptr   // back-link to associated m (nil if idle)
-	mcache      *mcache
-	pcache      pageCache
-	raceprocctx uintptr
-
-	deferpool    []*_defer // pool of available defer structs (see panic.go)
-	deferpoolbuf [32]*_defer
-
-	// Cache of goroutine ids, amortizes accesses to runtime·sched.goidgen.
-	goidcache    uint64
-	goidcacheend uint64
-
-	// Queue of runnable goroutines. Accessed without lock.
-	runqhead uint32
-	runqtail uint32
-	runq     [256]guintptr
-	// runnext, if non-nil, is a runnable G that was ready'd by
-	// the current G and should be run next instead of what's in
-	// runq if there's time remaining in the running G's time
-	// slice. It will inherit the time left in the current time
-	// slice. If a set of goroutines is locked in a
-	// communicate-and-wait pattern, this schedules that set as a
-	// unit and eliminates the (potentially large) scheduling
-	// latency that otherwise arises from adding the ready'd
-	// goroutines to the end of the run queue.
-	//
-	// Note that while other P's may atomically CAS this to zero,
-	// only the owner P can CAS it to a valid G.
-	runnext guintptr
-
-	// Available G's (status == Gdead)
-	gFree struct {
-		gList
-		n int32
-	}
-
-	sudogcache []*sudog
-	sudogbuf   [128]*sudog
-
-	// Cache of mspan objects from the heap.
-	mspancache struct {
-		// We need an explicit length here because this field is used
-		// in allocation codepaths where write barriers are not allowed,
-		// and eliminating the write barrier/keeping it eliminated from
-		// slice updates is tricky, moreso than just managing the length
-		// ourselves.
-		len int
-		buf [128]*mspan
-	}
-
-	tracebuf traceBufPtr
-
-	// traceSweep indicates the sweep events should be traced.
-	// This is used to defer the sweep start event until a span
-	// has actually been swept.
-	traceSweep bool
-	// traceSwept and traceReclaimed track the number of bytes
-	// swept and reclaimed by sweeping in the current sweep loop.
-	traceSwept, traceReclaimed uintptr
-
-	palloc persistentAlloc // per-P to avoid mutex
-
-	_ uint32 // Alignment for atomic fields below
-
-	// The when field of the first entry on the timer heap.
-	// This is updated using atomic functions.
-	// This is 0 if the timer heap is empty.
-	timer0When uint64
-
-	// The earliest known nextwhen field of a timer with
-	// timerModifiedEarlier status. Because the timer may have been
-	// modified again, there need not be any timer with this value.
-	// This is updated using atomic functions.
-	// This is 0 if there are no timerModifiedEarlier timers.
-	timerModifiedEarliest uint64
-
-	// Per-P GC state
-	gcAssistTime         int64 // Nanoseconds in assistAlloc
-	gcFractionalMarkTime int64 // Nanoseconds in fractional mark worker (atomic)
-
-	// gcMarkWorkerMode is the mode for the next mark worker to run in.
-	// That is, this is used to communicate with the worker goroutine
-	// selected for immediate execution by
-	// gcController.findRunnableGCWorker. When scheduling other goroutines,
-	// this field must be set to gcMarkWorkerNotWorker.
-	gcMarkWorkerMode gcMarkWorkerMode
-	// gcMarkWorkerStartTime is the nanotime() at which the most recent
-	// mark worker started.
-	gcMarkWorkerStartTime int64
-
-	// gcw is this P's GC work buffer cache. The work buffer is
-	// filled by write barriers, drained by mutator assists, and
-	// disposed on certain GC state transitions.
-	gcw gcWork
-
-	// wbBuf is this P's GC write barrier buffer.
-	//
-	// TODO: Consider caching this in the running G.
-	wbBuf wbBuf
-
-	runSafePointFn uint32 // if 1, run sched.safePointFn at next safe point
-
-	// statsSeq is a counter indicating whether this P is currently
-	// writing any stats. Its value is even when not, odd when it is.
-	statsSeq uint32
-
-	// Lock for timers. We normally access the timers while running
-	// on this P, but the scheduler can also do it from a different P.
-	timersLock mutex
-
-	// Actions to take at some time. This is used to implement the
-	// standard library's time package.
-	// Must hold timersLock to access.
-	timers []*timer
-
-	// Number of timers in P's heap.
-	// Modified using atomic instructions.
-	numTimers uint32
-
-	// Number of timerDeleted timers in P's heap.
-	// Modified using atomic instructions.
-	deletedTimers uint32
-
-	// Race context used while executing timer functions.
-	timerRaceCtx uintptr
-
-	// scannableStackSizeDelta accumulates the amount of stack space held by
-	// live goroutines (i.e. those eligible for stack scanning).
-	// Flushed to gcController.scannableStackSize once scannableStackSizeSlack
-	// or -scannableStackSizeSlack is reached.
-	scannableStackSizeDelta int64
-
-	// preempt is set to indicate that this P should be enter the
-	// scheduler ASAP (regardless of what G is running on it).
-	preempt bool
-
-	// Padding is no longer needed. False sharing is now not a worry because p is large enough
-	// that its size class is an integer multiple of the cache line size (for any of our architectures).
-}
-
-type schedt struct {
-	// accessed atomically. keep at top to ensure alignment on 32-bit systems.
-	goidgen   uint64
-	lastpoll  uint64 // time of last network poll, 0 if currently polling
-	pollUntil uint64 // time to which current poll is sleeping
-
-	lock mutex
-
-	// When increasing nmidle, nmidlelocked, nmsys, or nmfreed, be
-	// sure to call checkdead().
-
-	midle        muintptr // idle m's waiting for work
-	nmidle       int32    // number of idle m's waiting for work
-	nmidlelocked int32    // number of locked m's waiting for work
-	mnext        int64    // number of m's that have been created and next M ID
-	maxmcount    int32    // maximum number of m's allowed (or die)
-	nmsys        int32    // number of system m's not counted for deadlock
-	nmfreed      int64    // cumulative number of freed m's
-
-	ngsys uint32 // number of system goroutines; updated atomically
-
-	pidle      puintptr // idle p's
-	npidle     uint32
-	nmspinning uint32 // See "Worker thread parking/unparking" comment in proc.go.
-
-	// Global runnable queue.
-	runq     gQueue
-	runqsize int32
-
-	// disable controls selective disabling of the scheduler.
-	//
-	// Use schedEnableUser to control this.
-	//
-	// disable is protected by sched.lock.
-	disable struct {
-		// user disables scheduling of user goroutines.
-		user     bool
-		runnable gQueue // pending runnable Gs
-		n        int32  // length of runnable
-	}
-
-	// Global cache of dead G's.
-	gFree struct {
-		lock    mutex
-		stack   gList // Gs with stacks
-		noStack gList // Gs without stacks
-		n       int32
-	}
-
-	// Central cache of sudog structs.
-	sudoglock  mutex
-	sudogcache *sudog
-
-	// Central pool of available defer structs.
-	deferlock mutex
-	deferpool *_defer
-
-	// freem is the list of m's waiting to be freed when their
-	// m.exited is set. Linked through m.freelink.
-	freem *m
-
-	gcwaiting  uint32 // gc is waiting to run
-	stopwait   int32
-	stopnote   note
-	sysmonwait uint32
-	sysmonnote note
-
-	// safepointFn should be called on each P at the next GC
-	// safepoint if p.runSafePointFn is set.
-	safePointFn   func(*p)
-	safePointWait int32
-	safePointNote note
-
-	profilehz int32 // cpu profiling rate
-
-	procresizetime int64 // nanotime() of last change to gomaxprocs
-	totaltime      int64 // ∫gomaxprocs dt up to procresizetime
-
-	// sysmonlock protects sysmon's actions on the runtime.
-	//
-	// Acquire and hold this mutex to block sysmon from interacting
-	// with the rest of the runtime.
-	sysmonlock mutex
-
-	// timeToRun is a distribution of scheduling latencies, defined
-	// as the sum of time a G spends in the _Grunnable state before
-	// it transitions to _Grunning.
-	//
-	// timeToRun is protected by sched.lock.
-	timeToRun timeHistogram
-}
-
-// Values for the flags field of a sigTabT.
-const (
-	_SigNotify   = 1 << iota // let signal.Notify have signal, even if from kernel
-	_SigKill                 // if signal.Notify doesn't take it, exit quietly
-	_SigThrow                // if signal.Notify doesn't take it, exit loudly
-	_SigPanic                // if the signal is from the kernel, panic
-	_SigDefault              // if the signal isn't explicitly requested, don't monitor it
-	_SigGoExit               // cause all runtime procs to exit (only used on Plan 9).
-	_SigSetStack             // Don't explicitly install handler, but add SA_ONSTACK to existing libc handler
-	_SigUnblock              // always unblock; see blockableSig
-	_SigIgn                  // _SIG_DFL action is to ignore the signal
-)
-
-// Layout of in-memory per-function information prepared by linker
-// See https://golang.org/s/go12symtab.
-// Keep in sync with linker (../cmd/link/internal/ld/pcln.go:/pclntab)
-// and with package debug/gosym and with symtab.go in package runtime.
-type _func struct {
-	entryoff uint32 // start pc, as offset from moduledata.text/pcHeader.textStart
-	nameoff  int32  // function name
-
-	args        int32  // in/out args size
-	deferreturn uint32 // offset of start of a deferreturn call instruction from entry, if any.
-
-	pcsp      uint32
-	pcfile    uint32
-	pcln      uint32
-	npcdata   uint32
-	cuOffset  uint32 // runtime.cutab offset of this function's CU
-	funcID    funcID // set for certain special runtime functions
-	flag      funcFlag
-	_         [1]byte // pad
-	nfuncdata uint8   // must be last, must end on a uint32-aligned boundary
-}
-
-// Pseudo-Func that is returned for PCs that occur in inlined code.
-// A *Func can be either a *_func or a *funcinl, and they are distinguished
-// by the first uintptr.
-type funcinl struct {
-	ones  uint32  // set to ^0 to distinguish from _func
-	entry uintptr // entry of the real (the "outermost") frame
-	name  string
-	file  string
-	line  int
-}
-
-// layout of Itab known to compilers
-// allocated in non-garbage-collected memory
-// Needs to be in sync with
-// ../cmd/compile/internal/reflectdata/reflect.go:/^func.WriteTabs.
-type itab struct {
-	inter *interfacetype
-	_type *_type
-	hash  uint32 // copy of _type.hash. Used for type switches.
-	_     [4]byte
-	fun   [1]uintptr // variable sized. fun[0]==0 means _type does not implement inter.
-}
-
-// Lock-free stack node.
-// Also known to export_test.go.
-type lfnode struct {
-	next    uint64
-	pushcnt uintptr
-}
-
-type forcegcstate struct {
-	lock mutex
-	g    *g
-	idle uint32
-}
-
-// extendRandom extends the random numbers in r[:n] to the whole slice r.
-// Treats n<0 as n==0.
-func extendRandom(r []byte, n int) {
-	if n < 0 {
-		n = 0
-	}
-	for n < len(r) {
-		// Extend random bits using hash function & time seed
-		w := n
-		if w > 16 {
-			w = 16
-		}
-		h := memhash(unsafe.Pointer(&r[n-w]), uintptr(nanotime()), uintptr(w))
-		for i := 0; i < goarch.PtrSize && n < len(r); i++ {
-			r[n] = byte(h)
-			n++
-			h >>= 8
-		}
-	}
-}
-
-// A _defer holds an entry on the list of deferred calls.
-// If you add a field here, add code to clear it in deferProcStack.
-// This struct must match the code in cmd/compile/internal/ssagen/ssa.go:deferstruct
-// and cmd/compile/internal/ssagen/ssa.go:(*state).call.
-// Some defers will be allocated on the stack and some on the heap.
-// All defers are logically part of the stack, so write barriers to
-// initialize them are not required. All defers must be manually scanned,
-// and for heap defers, marked.
-type _defer struct {
-	started bool
-	heap    bool
-	// openDefer indicates that this _defer is for a frame with open-coded
-	// defers. We have only one defer record for the entire frame (which may
-	// currently have 0, 1, or more defers active).
-	openDefer bool
-	sp        uintptr // sp at time of defer
-	pc        uintptr // pc at time of defer
-	fn        func()  // can be nil for open-coded defers
-	_panic    *_panic // panic that is running defer
-	link      *_defer // next defer on G; can point to either heap or stack!
-
-	// If openDefer is true, the fields below record values about the stack
-	// frame and associated function that has the open-coded defer(s). sp
-	// above will be the sp for the frame, and pc will be address of the
-	// deferreturn call in the function.
-	fd   unsafe.Pointer // funcdata for the function associated with the frame
-	varp uintptr        // value of varp for the stack frame
-	// framepc is the current pc associated with the stack frame. Together,
-	// with sp above (which is the sp associated with the stack frame),
-	// framepc/sp can be used as pc/sp pair to continue a stack trace via
-	// gentraceback().
-	framepc uintptr
-}
-
-// A _panic holds information about an active panic.
-//
-// A _panic value must only ever live on the stack.
-//
-// The argp and link fields are stack pointers, but don't need special
-// handling during stack growth: because they are pointer-typed and
-// _panic values only live on the stack, regular stack pointer
-// adjustment takes care of them.
-type _panic struct {
-	argp      unsafe.Pointer // pointer to arguments of deferred call run during panic; cannot move - known to liblink
-	arg       any            // argument to panic
-	link      *_panic        // link to earlier panic
-	pc        uintptr        // where to return to in runtime if this panic is bypassed
-	sp        unsafe.Pointer // where to return to in runtime if this panic is bypassed
-	recovered bool           // whether this panic is over
-	aborted   bool           // the panic was aborted
-	goexit    bool
-}
-
-// stack traces
-type stkframe struct {
-	fn       funcInfo   // function being run
-	pc       uintptr    // program counter within fn
-	continpc uintptr    // program counter where execution can continue, or 0 if not
-	lr       uintptr    // program counter at caller aka link register
-	sp       uintptr    // stack pointer at pc
-	fp       uintptr    // stack pointer at caller aka frame pointer
-	varp     uintptr    // top of local variables
-	argp     uintptr    // pointer to function arguments
-	arglen   uintptr    // number of bytes at argp
-	argmap   *bitvector // force use of this argmap
-}
-
-// ancestorInfo records details of where a goroutine was started.
-type ancestorInfo struct {
-	pcs  []uintptr // pcs from the stack of this goroutine
-	goid int64     // goroutine id of this goroutine; original goroutine possibly dead
-	gopc uintptr   // pc of go statement that created this goroutine
-}
-
-const (
-	_TraceRuntimeFrames = 1 << iota // include frames for internal runtime functions.
-	_TraceTrap                      // the initial PC, SP are from a trap, not a return PC from a call
-	_TraceJumpStack                 // if traceback is on a systemstack, resume trace at g that called into it
-)
-
-// The maximum number of frames we print for a traceback
-const _TracebackMaxFrames = 100
-
-// A waitReason explains why a goroutine has been stopped.
-// See gopark. Do not re-use waitReasons, add new ones.
-type waitReason uint8
-
-const (
-	waitReasonZero                  waitReason = iota // ""
-	waitReasonGCAssistMarking                         // "GC assist marking"
-	waitReasonIOWait                                  // "IO wait"
-	waitReasonChanReceiveNilChan                      // "chan receive (nil chan)"
-	waitReasonChanSendNilChan                         // "chan send (nil chan)"
-	waitReasonDumpingHeap                             // "dumping heap"
-	waitReasonGarbageCollection                       // "garbage collection"
-	waitReasonGarbageCollectionScan                   // "garbage collection scan"
-	waitReasonPanicWait                               // "panicwait"
-	waitReasonSelect                                  // "select"
-	waitReasonSelectNoCases                           // "select (no cases)"
-	waitReasonGCAssistWait                            // "GC assist wait"
-	waitReasonGCSweepWait                             // "GC sweep wait"
-	waitReasonGCScavengeWait                          // "GC scavenge wait"
-	waitReasonChanReceive                             // "chan receive"
-	waitReasonChanSend                                // "chan send"
-	waitReasonFinalizerWait                           // "finalizer wait"
-	waitReasonForceGCIdle                             // "force gc (idle)"
-	waitReasonSemacquire                              // "semacquire"
-	waitReasonSleep                                   // "sleep"
-	waitReasonSyncCondWait                            // "sync.Cond.Wait"
-	waitReasonTimerGoroutineIdle                      // "timer goroutine (idle)"
-	waitReasonTraceReaderBlocked                      // "trace reader (blocked)"
-	waitReasonWaitForGCCycle                          // "wait for GC cycle"
-	waitReasonGCWorkerIdle                            // "GC worker (idle)"
-	waitReasonPreempted                               // "preempted"
-	waitReasonDebugCall                               // "debug call"
-)
-
-var waitReasonStrings = [...]string{
-	waitReasonZero:                  "",
-	waitReasonGCAssistMarking:       "GC assist marking",
-	waitReasonIOWait:                "IO wait",
-	waitReasonChanReceiveNilChan:    "chan receive (nil chan)",
-	waitReasonChanSendNilChan:       "chan send (nil chan)",
-	waitReasonDumpingHeap:           "dumping heap",
-	waitReasonGarbageCollection:     "garbage collection",
-	waitReasonGarbageCollectionScan: "garbage collection scan",
-	waitReasonPanicWait:             "panicwait",
-	waitReasonSelect:                "select",
-	waitReasonSelectNoCases:         "select (no cases)",
-	waitReasonGCAssistWait:          "GC assist wait",
-	waitReasonGCSweepWait:           "GC sweep wait",
-	waitReasonGCScavengeWait:        "GC scavenge wait",
-	waitReasonChanReceive:           "chan receive",
-	waitReasonChanSend:              "chan send",
-	waitReasonFinalizerWait:         "finalizer wait",
-	waitReasonForceGCIdle:           "force gc (idle)",
-	waitReasonSemacquire:            "semacquire",
-	waitReasonSleep:                 "sleep",
-	waitReasonSyncCondWait:          "sync.Cond.Wait",
-	waitReasonTimerGoroutineIdle:    "timer goroutine (idle)",
-	waitReasonTraceReaderBlocked:    "trace reader (blocked)",
-	waitReasonWaitForGCCycle:        "wait for GC cycle",
-	waitReasonGCWorkerIdle:          "GC worker (idle)",
-	waitReasonPreempted:             "preempted",
-	waitReasonDebugCall:             "debug call",
-}
-
-func (w waitReason) String() string {
-	if w < 0 || w >= waitReason(len(waitReasonStrings)) {
-		return "unknown wait reason"
-	}
-	return waitReasonStrings[w]
-}
-
-var (
-	allm       *m
-	gomaxprocs int32
-	ncpu       int32
-	forcegc    forcegcstate
-	sched      schedt
-	newprocs   int32
-
-	// allpLock protects P-less reads and size changes of allp, idlepMask,
-	// and timerpMask, and all writes to allp.
-	allpLock mutex
-	// len(allp) == gomaxprocs; may change at safe points, otherwise
-	// immutable.
-	allp []*p
-	// Bitmask of Ps in _Pidle list, one bit per P. Reads and writes must
-	// be atomic. Length may change at safe points.
-	//
-	// Each P must update only its own bit. In order to maintain
-	// consistency, a P going idle must the idle mask simultaneously with
-	// updates to the idle P list under the sched.lock, otherwise a racing
-	// pidleget may clear the mask before pidleput sets the mask,
-	// corrupting the bitmap.
-	//
-	// N.B., procresize takes ownership of all Ps in stopTheWorldWithSema.
-	idlepMask pMask
-	// Bitmask of Ps that may have a timer, one bit per P. Reads and writes
-	// must be atomic. Length may change at safe points.
-	timerpMask pMask
-
-	// Pool of GC parked background workers. Entries are type
-	// *gcBgMarkWorkerNode.
-	gcBgMarkWorkerPool lfstack
-
-	// Total number of gcBgMarkWorker goroutines. Protected by worldsema.
-	gcBgMarkWorkerCount int32
-
-	// Information about what cpu features are available.
-	// Packages outside the runtime should not use these
-	// as they are not an external api.
-	// Set on startup in asm_{386,amd64}.s
-	processorVersionInfo uint32
-	isIntel              bool
-
-	goarm uint8 // set by cmd/link on arm systems
-)
-
-// Set by the linker so the runtime can determine the buildmode.
-var (
-	islibrary bool // -buildmode=c-shared
-	isarchive bool // -buildmode=c-archive
-)
-
-// Must agree with internal/buildcfg.Experiment.FramePointer.
-const framepointer_enabled = GOARCH == "amd64" || GOARCH == "arm64"
diff --git a/contrib/go/_std_1.18/src/runtime/sema.go b/contrib/go/_std_1.18/src/runtime/sema.go
deleted file mode 100644
index f94c1aa891..0000000000
--- a/contrib/go/_std_1.18/src/runtime/sema.go
+++ /dev/null
@@ -1,617 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Semaphore implementation exposed to Go.
-// Intended use is provide a sleep and wakeup
-// primitive that can be used in the contended case
-// of other synchronization primitives.
-// Thus it targets the same goal as Linux's futex,
-// but it has much simpler semantics.
-//
-// That is, don't think of these as semaphores.
-// Think of them as a way to implement sleep and wakeup
-// such that every sleep is paired with a single wakeup,
-// even if, due to races, the wakeup happens before the sleep.
-//
-// See Mullender and Cox, ``Semaphores in Plan 9,''
-// https://swtch.com/semaphore.pdf
-
-package runtime
-
-import (
-	"internal/cpu"
-	"runtime/internal/atomic"
-	"unsafe"
-)
-
-// Asynchronous semaphore for sync.Mutex.
-
-// A semaRoot holds a balanced tree of sudog with distinct addresses (s.elem).
-// Each of those sudog may in turn point (through s.waitlink) to a list
-// of other sudogs waiting on the same address.
-// The operations on the inner lists of sudogs with the same address
-// are all O(1). The scanning of the top-level semaRoot list is O(log n),
-// where n is the number of distinct addresses with goroutines blocked
-// on them that hash to the given semaRoot.
-// See golang.org/issue/17953 for a program that worked badly
-// before we introduced the second level of list, and test/locklinear.go
-// for a test that exercises this.
-type semaRoot struct {
-	lock  mutex
-	treap *sudog // root of balanced tree of unique waiters.
-	nwait uint32 // Number of waiters. Read w/o the lock.
-}
-
-// Prime to not correlate with any user patterns.
-const semTabSize = 251
-
-var semtable [semTabSize]struct {
-	root semaRoot
-	pad  [cpu.CacheLinePadSize - unsafe.Sizeof(semaRoot{})]byte
-}
-
-//go:linkname sync_runtime_Semacquire sync.runtime_Semacquire
-func sync_runtime_Semacquire(addr *uint32) {
-	semacquire1(addr, false, semaBlockProfile, 0)
-}
-
-//go:linkname poll_runtime_Semacquire internal/poll.runtime_Semacquire
-func poll_runtime_Semacquire(addr *uint32) {
-	semacquire1(addr, false, semaBlockProfile, 0)
-}
-
-//go:linkname sync_runtime_Semrelease sync.runtime_Semrelease
-func sync_runtime_Semrelease(addr *uint32, handoff bool, skipframes int) {
-	semrelease1(addr, handoff, skipframes)
-}
-
-//go:linkname sync_runtime_SemacquireMutex sync.runtime_SemacquireMutex
-func sync_runtime_SemacquireMutex(addr *uint32, lifo bool, skipframes int) {
-	semacquire1(addr, lifo, semaBlockProfile|semaMutexProfile, skipframes)
-}
-
-//go:linkname poll_runtime_Semrelease internal/poll.runtime_Semrelease
-func poll_runtime_Semrelease(addr *uint32) {
-	semrelease(addr)
-}
-
-func readyWithTime(s *sudog, traceskip int) {
-	if s.releasetime != 0 {
-		s.releasetime = cputicks()
-	}
-	goready(s.g, traceskip)
-}
-
-type semaProfileFlags int
-
-const (
-	semaBlockProfile semaProfileFlags = 1 << iota
-	semaMutexProfile
-)
-
-// Called from runtime.
-func semacquire(addr *uint32) {
-	semacquire1(addr, false, 0, 0)
-}
-
-func semacquire1(addr *uint32, lifo bool, profile semaProfileFlags, skipframes int) {
-	gp := getg()
-	if gp != gp.m.curg {
-		throw("semacquire not on the G stack")
-	}
-
-	// Easy case.
-	if cansemacquire(addr) {
-		return
-	}
-
-	// Harder case:
-	//	increment waiter count
-	//	try cansemacquire one more time, return if succeeded
-	//	enqueue itself as a waiter
-	//	sleep
-	//	(waiter descriptor is dequeued by signaler)
-	s := acquireSudog()
-	root := semroot(addr)
-	t0 := int64(0)
-	s.releasetime = 0
-	s.acquiretime = 0
-	s.ticket = 0
-	if profile&semaBlockProfile != 0 && blockprofilerate > 0 {
-		t0 = cputicks()
-		s.releasetime = -1
-	}
-	if profile&semaMutexProfile != 0 && mutexprofilerate > 0 {
-		if t0 == 0 {
-			t0 = cputicks()
-		}
-		s.acquiretime = t0
-	}
-	for {
-		lockWithRank(&root.lock, lockRankRoot)
-		// Add ourselves to nwait to disable "easy case" in semrelease.
-		atomic.Xadd(&root.nwait, 1)
-		// Check cansemacquire to avoid missed wakeup.
-		if cansemacquire(addr) {
-			atomic.Xadd(&root.nwait, -1)
-			unlock(&root.lock)
-			break
-		}
-		// Any semrelease after the cansemacquire knows we're waiting
-		// (we set nwait above), so go to sleep.
-		root.queue(addr, s, lifo)
-		goparkunlock(&root.lock, waitReasonSemacquire, traceEvGoBlockSync, 4+skipframes)
-		if s.ticket != 0 || cansemacquire(addr) {
-			break
-		}
-	}
-	if s.releasetime > 0 {
-		blockevent(s.releasetime-t0, 3+skipframes)
-	}
-	releaseSudog(s)
-}
-
-func semrelease(addr *uint32) {
-	semrelease1(addr, false, 0)
-}
-
-func semrelease1(addr *uint32, handoff bool, skipframes int) {
-	root := semroot(addr)
-	atomic.Xadd(addr, 1)
-
-	// Easy case: no waiters?
-	// This check must happen after the xadd, to avoid a missed wakeup
-	// (see loop in semacquire).
-	if atomic.Load(&root.nwait) == 0 {
-		return
-	}
-
-	// Harder case: search for a waiter and wake it.
-	lockWithRank(&root.lock, lockRankRoot)
-	if atomic.Load(&root.nwait) == 0 {
-		// The count is already consumed by another goroutine,
-		// so no need to wake up another goroutine.
-		unlock(&root.lock)
-		return
-	}
-	s, t0 := root.dequeue(addr)
-	if s != nil {
-		atomic.Xadd(&root.nwait, -1)
-	}
-	unlock(&root.lock)
-	if s != nil { // May be slow or even yield, so unlock first
-		acquiretime := s.acquiretime
-		if acquiretime != 0 {
-			mutexevent(t0-acquiretime, 3+skipframes)
-		}
-		if s.ticket != 0 {
-			throw("corrupted semaphore ticket")
-		}
-		if handoff && cansemacquire(addr) {
-			s.ticket = 1
-		}
-		readyWithTime(s, 5+skipframes)
-		if s.ticket == 1 && getg().m.locks == 0 {
-			// Direct G handoff
-			// readyWithTime has added the waiter G as runnext in the
-			// current P; we now call the scheduler so that we start running
-			// the waiter G immediately.
-			// Note that waiter inherits our time slice: this is desirable
-			// to avoid having a highly contended semaphore hog the P
-			// indefinitely. goyield is like Gosched, but it emits a
-			// "preempted" trace event instead and, more importantly, puts
-			// the current G on the local runq instead of the global one.
-			// We only do this in the starving regime (handoff=true), as in
-			// the non-starving case it is possible for a different waiter
-			// to acquire the semaphore while we are yielding/scheduling,
-			// and this would be wasteful. We wait instead to enter starving
-			// regime, and then we start to do direct handoffs of ticket and
-			// P.
-			// See issue 33747 for discussion.
-			goyield()
-		}
-	}
-}
-
-func semroot(addr *uint32) *semaRoot {
-	return &semtable[(uintptr(unsafe.Pointer(addr))>>3)%semTabSize].root
-}
-
-func cansemacquire(addr *uint32) bool {
-	for {
-		v := atomic.Load(addr)
-		if v == 0 {
-			return false
-		}
-		if atomic.Cas(addr, v, v-1) {
-			return true
-		}
-	}
-}
-
-// queue adds s to the blocked goroutines in semaRoot.
-func (root *semaRoot) queue(addr *uint32, s *sudog, lifo bool) {
-	s.g = getg()
-	s.elem = unsafe.Pointer(addr)
-	s.next = nil
-	s.prev = nil
-
-	var last *sudog
-	pt := &root.treap
-	for t := *pt; t != nil; t = *pt {
-		if t.elem == unsafe.Pointer(addr) {
-			// Already have addr in list.
-			if lifo {
-				// Substitute s in t's place in treap.
-				*pt = s
-				s.ticket = t.ticket
-				s.acquiretime = t.acquiretime
-				s.parent = t.parent
-				s.prev = t.prev
-				s.next = t.next
-				if s.prev != nil {
-					s.prev.parent = s
-				}
-				if s.next != nil {
-					s.next.parent = s
-				}
-				// Add t first in s's wait list.
-				s.waitlink = t
-				s.waittail = t.waittail
-				if s.waittail == nil {
-					s.waittail = t
-				}
-				t.parent = nil
-				t.prev = nil
-				t.next = nil
-				t.waittail = nil
-			} else {
-				// Add s to end of t's wait list.
-				if t.waittail == nil {
-					t.waitlink = s
-				} else {
-					t.waittail.waitlink = s
-				}
-				t.waittail = s
-				s.waitlink = nil
-			}
-			return
-		}
-		last = t
-		if uintptr(unsafe.Pointer(addr)) < uintptr(t.elem) {
-			pt = &t.prev
-		} else {
-			pt = &t.next
-		}
-	}
-
-	// Add s as new leaf in tree of unique addrs.
-	// The balanced tree is a treap using ticket as the random heap priority.
-	// That is, it is a binary tree ordered according to the elem addresses,
-	// but then among the space of possible binary trees respecting those
-	// addresses, it is kept balanced on average by maintaining a heap ordering
-	// on the ticket: s.ticket <= both s.prev.ticket and s.next.ticket.
-	// https://en.wikipedia.org/wiki/Treap
-	// https://faculty.washington.edu/aragon/pubs/rst89.pdf
-	//
-	// s.ticket compared with zero in couple of places, therefore set lowest bit.
-	// It will not affect treap's quality noticeably.
-	s.ticket = fastrand() | 1
-	s.parent = last
-	*pt = s
-
-	// Rotate up into tree according to ticket (priority).
-	for s.parent != nil && s.parent.ticket > s.ticket {
-		if s.parent.prev == s {
-			root.rotateRight(s.parent)
-		} else {
-			if s.parent.next != s {
-				panic("semaRoot queue")
-			}
-			root.rotateLeft(s.parent)
-		}
-	}
-}
-
-// dequeue searches for and finds the first goroutine
-// in semaRoot blocked on addr.
-// If the sudog was being profiled, dequeue returns the time
-// at which it was woken up as now. Otherwise now is 0.
-func (root *semaRoot) dequeue(addr *uint32) (found *sudog, now int64) {
-	ps := &root.treap
-	s := *ps
-	for ; s != nil; s = *ps {
-		if s.elem == unsafe.Pointer(addr) {
-			goto Found
-		}
-		if uintptr(unsafe.Pointer(addr)) < uintptr(s.elem) {
-			ps = &s.prev
-		} else {
-			ps = &s.next
-		}
-	}
-	return nil, 0
-
-Found:
-	now = int64(0)
-	if s.acquiretime != 0 {
-		now = cputicks()
-	}
-	if t := s.waitlink; t != nil {
-		// Substitute t, also waiting on addr, for s in root tree of unique addrs.
-		*ps = t
-		t.ticket = s.ticket
-		t.parent = s.parent
-		t.prev = s.prev
-		if t.prev != nil {
-			t.prev.parent = t
-		}
-		t.next = s.next
-		if t.next != nil {
-			t.next.parent = t
-		}
-		if t.waitlink != nil {
-			t.waittail = s.waittail
-		} else {
-			t.waittail = nil
-		}
-		t.acquiretime = now
-		s.waitlink = nil
-		s.waittail = nil
-	} else {
-		// Rotate s down to be leaf of tree for removal, respecting priorities.
-		for s.next != nil || s.prev != nil {
-			if s.next == nil || s.prev != nil && s.prev.ticket < s.next.ticket {
-				root.rotateRight(s)
-			} else {
-				root.rotateLeft(s)
-			}
-		}
-		// Remove s, now a leaf.
-		if s.parent != nil {
-			if s.parent.prev == s {
-				s.parent.prev = nil
-			} else {
-				s.parent.next = nil
-			}
-		} else {
-			root.treap = nil
-		}
-	}
-	s.parent = nil
-	s.elem = nil
-	s.next = nil
-	s.prev = nil
-	s.ticket = 0
-	return s, now
-}
-
-// rotateLeft rotates the tree rooted at node x.
-// turning (x a (y b c)) into (y (x a b) c).
-func (root *semaRoot) rotateLeft(x *sudog) {
-	// p -> (x a (y b c))
-	p := x.parent
-	y := x.next
-	b := y.prev
-
-	y.prev = x
-	x.parent = y
-	x.next = b
-	if b != nil {
-		b.parent = x
-	}
-
-	y.parent = p
-	if p == nil {
-		root.treap = y
-	} else if p.prev == x {
-		p.prev = y
-	} else {
-		if p.next != x {
-			throw("semaRoot rotateLeft")
-		}
-		p.next = y
-	}
-}
-
-// rotateRight rotates the tree rooted at node y.
-// turning (y (x a b) c) into (x a (y b c)).
-func (root *semaRoot) rotateRight(y *sudog) {
-	// p -> (y (x a b) c)
-	p := y.parent
-	x := y.prev
-	b := x.next
-
-	x.next = y
-	y.parent = x
-	y.prev = b
-	if b != nil {
-		b.parent = y
-	}
-
-	x.parent = p
-	if p == nil {
-		root.treap = x
-	} else if p.prev == y {
-		p.prev = x
-	} else {
-		if p.next != y {
-			throw("semaRoot rotateRight")
-		}
-		p.next = x
-	}
-}
-
-// notifyList is a ticket-based notification list used to implement sync.Cond.
-//
-// It must be kept in sync with the sync package.
-type notifyList struct {
-	// wait is the ticket number of the next waiter. It is atomically
-	// incremented outside the lock.
-	wait uint32
-
-	// notify is the ticket number of the next waiter to be notified. It can
-	// be read outside the lock, but is only written to with lock held.
-	//
-	// Both wait & notify can wrap around, and such cases will be correctly
-	// handled as long as their "unwrapped" difference is bounded by 2^31.
-	// For this not to be the case, we'd need to have 2^31+ goroutines
-	// blocked on the same condvar, which is currently not possible.
-	notify uint32
-
-	// List of parked waiters.
-	lock mutex
-	head *sudog
-	tail *sudog
-}
-
-// less checks if a < b, considering a & b running counts that may overflow the
-// 32-bit range, and that their "unwrapped" difference is always less than 2^31.
-func less(a, b uint32) bool {
-	return int32(a-b) < 0
-}
-
-// notifyListAdd adds the caller to a notify list such that it can receive
-// notifications. The caller must eventually call notifyListWait to wait for
-// such a notification, passing the returned ticket number.
-//go:linkname notifyListAdd sync.runtime_notifyListAdd
-func notifyListAdd(l *notifyList) uint32 {
-	// This may be called concurrently, for example, when called from
-	// sync.Cond.Wait while holding a RWMutex in read mode.
-	return atomic.Xadd(&l.wait, 1) - 1
-}
-
-// notifyListWait waits for a notification. If one has been sent since
-// notifyListAdd was called, it returns immediately. Otherwise, it blocks.
-//go:linkname notifyListWait sync.runtime_notifyListWait
-func notifyListWait(l *notifyList, t uint32) {
-	lockWithRank(&l.lock, lockRankNotifyList)
-
-	// Return right away if this ticket has already been notified.
-	if less(t, l.notify) {
-		unlock(&l.lock)
-		return
-	}
-
-	// Enqueue itself.
-	s := acquireSudog()
-	s.g = getg()
-	s.ticket = t
-	s.releasetime = 0
-	t0 := int64(0)
-	if blockprofilerate > 0 {
-		t0 = cputicks()
-		s.releasetime = -1
-	}
-	if l.tail == nil {
-		l.head = s
-	} else {
-		l.tail.next = s
-	}
-	l.tail = s
-	goparkunlock(&l.lock, waitReasonSyncCondWait, traceEvGoBlockCond, 3)
-	if t0 != 0 {
-		blockevent(s.releasetime-t0, 2)
-	}
-	releaseSudog(s)
-}
-
-// notifyListNotifyAll notifies all entries in the list.
-//go:linkname notifyListNotifyAll sync.runtime_notifyListNotifyAll
-func notifyListNotifyAll(l *notifyList) {
-	// Fast-path: if there are no new waiters since the last notification
-	// we don't need to acquire the lock.
-	if atomic.Load(&l.wait) == atomic.Load(&l.notify) {
-		return
-	}
-
-	// Pull the list out into a local variable, waiters will be readied
-	// outside the lock.
-	lockWithRank(&l.lock, lockRankNotifyList)
-	s := l.head
-	l.head = nil
-	l.tail = nil
-
-	// Update the next ticket to be notified. We can set it to the current
-	// value of wait because any previous waiters are already in the list
-	// or will notice that they have already been notified when trying to
-	// add themselves to the list.
-	atomic.Store(&l.notify, atomic.Load(&l.wait))
-	unlock(&l.lock)
-
-	// Go through the local list and ready all waiters.
-	for s != nil {
-		next := s.next
-		s.next = nil
-		readyWithTime(s, 4)
-		s = next
-	}
-}
-
-// notifyListNotifyOne notifies one entry in the list.
-//go:linkname notifyListNotifyOne sync.runtime_notifyListNotifyOne
-func notifyListNotifyOne(l *notifyList) {
-	// Fast-path: if there are no new waiters since the last notification
-	// we don't need to acquire the lock at all.
-	if atomic.Load(&l.wait) == atomic.Load(&l.notify) {
-		return
-	}
-
-	lockWithRank(&l.lock, lockRankNotifyList)
-
-	// Re-check under the lock if we need to do anything.
-	t := l.notify
-	if t == atomic.Load(&l.wait) {
-		unlock(&l.lock)
-		return
-	}
-
-	// Update the next notify ticket number.
-	atomic.Store(&l.notify, t+1)
-
-	// Try to find the g that needs to be notified.
-	// If it hasn't made it to the list yet we won't find it,
-	// but it won't park itself once it sees the new notify number.
-	//
-	// This scan looks linear but essentially always stops quickly.
-	// Because g's queue separately from taking numbers,
-	// there may be minor reorderings in the list, but we
-	// expect the g we're looking for to be near the front.
-	// The g has others in front of it on the list only to the
-	// extent that it lost the race, so the iteration will not
-	// be too long. This applies even when the g is missing:
-	// it hasn't yet gotten to sleep and has lost the race to
-	// the (few) other g's that we find on the list.
-	for p, s := (*sudog)(nil), l.head; s != nil; p, s = s, s.next {
-		if s.ticket == t {
-			n := s.next
-			if p != nil {
-				p.next = n
-			} else {
-				l.head = n
-			}
-			if n == nil {
-				l.tail = p
-			}
-			unlock(&l.lock)
-			s.next = nil
-			readyWithTime(s, 4)
-			return
-		}
-	}
-	unlock(&l.lock)
-}
-
-//go:linkname notifyListCheck sync.runtime_notifyListCheck
-func notifyListCheck(sz uintptr) {
-	if sz != unsafe.Sizeof(notifyList{}) {
-		print("runtime: bad notifyList size - sync=", sz, " runtime=", unsafe.Sizeof(notifyList{}), "\n")
-		throw("bad notifyList size")
-	}
-}
-
-//go:linkname sync_nanotime sync.runtime_nanotime
-func sync_nanotime() int64 {
-	return nanotime()
-}
diff --git a/contrib/go/_std_1.18/src/runtime/signal_darwin_amd64.go b/contrib/go/_std_1.18/src/runtime/signal_darwin_amd64.go
deleted file mode 100644
index abc212ad51..0000000000
--- a/contrib/go/_std_1.18/src/runtime/signal_darwin_amd64.go
+++ /dev/null
@@ -1,92 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import "unsafe"
-
-type sigctxt struct {
-	info *siginfo
-	ctxt unsafe.Pointer
-}
-
-//go:nosplit
-//go:nowritebarrierrec
-func (c *sigctxt) regs() *regs64 { return &(*ucontext)(c.ctxt).uc_mcontext.ss }
-
-func (c *sigctxt) rax() uint64 { return c.regs().rax }
-func (c *sigctxt) rbx() uint64 { return c.regs().rbx }
-func (c *sigctxt) rcx() uint64 { return c.regs().rcx }
-func (c *sigctxt) rdx() uint64 { return c.regs().rdx }
-func (c *sigctxt) rdi() uint64 { return c.regs().rdi }
-func (c *sigctxt) rsi() uint64 { return c.regs().rsi }
-func (c *sigctxt) rbp() uint64 { return c.regs().rbp }
-func (c *sigctxt) rsp() uint64 { return c.regs().rsp }
-func (c *sigctxt) r8() uint64  { return c.regs().r8 }
-func (c *sigctxt) r9() uint64  { return c.regs().r9 }
-func (c *sigctxt) r10() uint64 { return c.regs().r10 }
-func (c *sigctxt) r11() uint64 { return c.regs().r11 }
-func (c *sigctxt) r12() uint64 { return c.regs().r12 }
-func (c *sigctxt) r13() uint64 { return c.regs().r13 }
-func (c *sigctxt) r14() uint64 { return c.regs().r14 }
-func (c *sigctxt) r15() uint64 { return c.regs().r15 }
-
-//go:nosplit
-//go:nowritebarrierrec
-func (c *sigctxt) rip() uint64 { return c.regs().rip }
-
-func (c *sigctxt) rflags() uint64  { return c.regs().rflags }
-func (c *sigctxt) cs() uint64      { return c.regs().cs }
-func (c *sigctxt) fs() uint64      { return c.regs().fs }
-func (c *sigctxt) gs() uint64      { return c.regs().gs }
-func (c *sigctxt) sigcode() uint64 { return uint64(c.info.si_code) }
-func (c *sigctxt) sigaddr() uint64 { return c.info.si_addr }
-
-func (c *sigctxt) set_rip(x uint64)     { c.regs().rip = x }
-func (c *sigctxt) set_rsp(x uint64)     { c.regs().rsp = x }
-func (c *sigctxt) set_sigcode(x uint64) { c.info.si_code = int32(x) }
-func (c *sigctxt) set_sigaddr(x uint64) { c.info.si_addr = x }
-
-//go:nosplit
-func (c *sigctxt) fixsigcode(sig uint32) {
-	switch sig {
-	case _SIGTRAP:
-		// OS X sets c.sigcode() == TRAP_BRKPT unconditionally for all SIGTRAPs,
-		// leaving no way to distinguish a breakpoint-induced SIGTRAP
-		// from an asynchronous signal SIGTRAP.
-		// They all look breakpoint-induced by default.
-		// Try looking at the code to see if it's a breakpoint.
-		// The assumption is that we're very unlikely to get an
-		// asynchronous SIGTRAP at just the moment that the
-		// PC started to point at unmapped memory.
-		pc := uintptr(c.rip())
-		// OS X will leave the pc just after the INT 3 instruction.
-		// INT 3 is usually 1 byte, but there is a 2-byte form.
-		code := (*[2]byte)(unsafe.Pointer(pc - 2))
-		if code[1] != 0xCC && (code[0] != 0xCD || code[1] != 3) {
-			// SIGTRAP on something other than INT 3.
-			c.set_sigcode(_SI_USER)
-		}
-
-	case _SIGSEGV:
-		// x86-64 has 48-bit virtual addresses. The top 16 bits must echo bit 47.
-		// The hardware delivers a different kind of fault for a malformed address
-		// than it does for an attempt to access a valid but unmapped address.
-		// OS X 10.9.2 mishandles the malformed address case, making it look like
-		// a user-generated signal (like someone ran kill -SEGV ourpid).
-		// We pass user-generated signals to os/signal, or else ignore them.
-		// Doing that here - and returning to the faulting code - results in an
-		// infinite loop. It appears the best we can do is rewrite what the kernel
-		// delivers into something more like the truth. The address used below
-		// has very little chance of being the one that caused the fault, but it is
-		// malformed, it is clearly not a real pointer, and if it does get printed
-		// in real life, people will probably search for it and find this code.
-		// There are no Google hits for b01dfacedebac1e or 0xb01dfacedebac1e
-		// as I type this comment.
-		if c.sigcode() == _SI_USER {
-			c.set_sigcode(_SI_USER + 1)
-			c.set_sigaddr(0xb01dfacedebac1e)
-		}
-	}
-}
diff --git a/contrib/go/_std_1.18/src/runtime/signal_unix.go b/contrib/go/_std_1.18/src/runtime/signal_unix.go
deleted file mode 100644
index 5cb51d10ba..0000000000
--- a/contrib/go/_std_1.18/src/runtime/signal_unix.go
+++ /dev/null
@@ -1,1320 +0,0 @@
-// Copyright 2012 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
-
-package runtime
-
-import (
-	"internal/abi"
-	"runtime/internal/atomic"
-	"runtime/internal/sys"
-	"unsafe"
-)
-
-// sigTabT is the type of an entry in the global sigtable array.
-// sigtable is inherently system dependent, and appears in OS-specific files,
-// but sigTabT is the same for all Unixy systems.
-// The sigtable array is indexed by a system signal number to get the flags
-// and printable name of each signal.
-type sigTabT struct {
-	flags int32
-	name  string
-}
-
-//go:linkname os_sigpipe os.sigpipe
-func os_sigpipe() {
-	systemstack(sigpipe)
-}
-
-func signame(sig uint32) string {
-	if sig >= uint32(len(sigtable)) {
-		return ""
-	}
-	return sigtable[sig].name
-}
-
-const (
-	_SIG_DFL uintptr = 0
-	_SIG_IGN uintptr = 1
-)
-
-// sigPreempt is the signal used for non-cooperative preemption.
-//
-// There's no good way to choose this signal, but there are some
-// heuristics:
-//
-// 1. It should be a signal that's passed-through by debuggers by
-// default. On Linux, this is SIGALRM, SIGURG, SIGCHLD, SIGIO,
-// SIGVTALRM, SIGPROF, and SIGWINCH, plus some glibc-internal signals.
-//
-// 2. It shouldn't be used internally by libc in mixed Go/C binaries
-// because libc may assume it's the only thing that can handle these
-// signals. For example SIGCANCEL or SIGSETXID.
-//
-// 3. It should be a signal that can happen spuriously without
-// consequences. For example, SIGALRM is a bad choice because the
-// signal handler can't tell if it was caused by the real process
-// alarm or not (arguably this means the signal is broken, but I
-// digress). SIGUSR1 and SIGUSR2 are also bad because those are often
-// used in meaningful ways by applications.
-//
-// 4. We need to deal with platforms without real-time signals (like
-// macOS), so those are out.
-//
-// We use SIGURG because it meets all of these criteria, is extremely
-// unlikely to be used by an application for its "real" meaning (both
-// because out-of-band data is basically unused and because SIGURG
-// doesn't report which socket has the condition, making it pretty
-// useless), and even if it is, the application has to be ready for
-// spurious SIGURG. SIGIO wouldn't be a bad choice either, but is more
-// likely to be used for real.
-const sigPreempt = _SIGURG
-
-// Stores the signal handlers registered before Go installed its own.
-// These signal handlers will be invoked in cases where Go doesn't want to
-// handle a particular signal (e.g., signal occurred on a non-Go thread).
-// See sigfwdgo for more information on when the signals are forwarded.
-//
-// This is read by the signal handler; accesses should use
-// atomic.Loaduintptr and atomic.Storeuintptr.
-var fwdSig [_NSIG]uintptr
-
-// handlingSig is indexed by signal number and is non-zero if we are
-// currently handling the signal. Or, to put it another way, whether
-// the signal handler is currently set to the Go signal handler or not.
-// This is uint32 rather than bool so that we can use atomic instructions.
-var handlingSig [_NSIG]uint32
-
-// channels for synchronizing signal mask updates with the signal mask
-// thread
-var (
-	disableSigChan  chan uint32
-	enableSigChan   chan uint32
-	maskUpdatedChan chan struct{}
-)
-
-func init() {
-	// _NSIG is the number of signals on this operating system.
-	// sigtable should describe what to do for all the possible signals.
-	if len(sigtable) != _NSIG {
-		print("runtime: len(sigtable)=", len(sigtable), " _NSIG=", _NSIG, "\n")
-		throw("bad sigtable len")
-	}
-}
-
-var signalsOK bool
-
-// Initialize signals.
-// Called by libpreinit so runtime may not be initialized.
-//go:nosplit
-//go:nowritebarrierrec
-func initsig(preinit bool) {
-	if !preinit {
-		// It's now OK for signal handlers to run.
-		signalsOK = true
-	}
-
-	// For c-archive/c-shared this is called by libpreinit with
-	// preinit == true.
-	if (isarchive || islibrary) && !preinit {
-		return
-	}
-
-	for i := uint32(0); i < _NSIG; i++ {
-		t := &sigtable[i]
-		if t.flags == 0 || t.flags&_SigDefault != 0 {
-			continue
-		}
-
-		// We don't need to use atomic operations here because
-		// there shouldn't be any other goroutines running yet.
-		fwdSig[i] = getsig(i)
-
-		if !sigInstallGoHandler(i) {
-			// Even if we are not installing a signal handler,
-			// set SA_ONSTACK if necessary.
-			if fwdSig[i] != _SIG_DFL && fwdSig[i] != _SIG_IGN {
-				setsigstack(i)
-			} else if fwdSig[i] == _SIG_IGN {
-				sigInitIgnored(i)
-			}
-			continue
-		}
-
-		handlingSig[i] = 1
-		setsig(i, abi.FuncPCABIInternal(sighandler))
-	}
-}
-
-//go:nosplit
-//go:nowritebarrierrec
-func sigInstallGoHandler(sig uint32) bool {
-	// For some signals, we respect an inherited SIG_IGN handler
-	// rather than insist on installing our own default handler.
-	// Even these signals can be fetched using the os/signal package.
-	switch sig {
-	case _SIGHUP, _SIGINT:
-		if atomic.Loaduintptr(&fwdSig[sig]) == _SIG_IGN {
-			return false
-		}
-	}
-
-	if (GOOS == "linux" || GOOS == "android") && !iscgo && sig == sigPerThreadSyscall {
-		// sigPerThreadSyscall is the same signal used by glibc for
-		// per-thread syscalls on Linux. We use it for the same purpose
-		// in non-cgo binaries.
-		return true
-	}
-
-	t := &sigtable[sig]
-	if t.flags&_SigSetStack != 0 {
-		return false
-	}
-
-	// When built using c-archive or c-shared, only install signal
-	// handlers for synchronous signals and SIGPIPE and sigPreempt.
-	if (isarchive || islibrary) && t.flags&_SigPanic == 0 && sig != _SIGPIPE && sig != sigPreempt {
-		return false
-	}
-
-	return true
-}
-
-// sigenable enables the Go signal handler to catch the signal sig.
-// It is only called while holding the os/signal.handlers lock,
-// via os/signal.enableSignal and signal_enable.
-func sigenable(sig uint32) {
-	if sig >= uint32(len(sigtable)) {
-		return
-	}
-
-	// SIGPROF is handled specially for profiling.
-	if sig == _SIGPROF {
-		return
-	}
-
-	t := &sigtable[sig]
-	if t.flags&_SigNotify != 0 {
-		ensureSigM()
-		enableSigChan <- sig
-		<-maskUpdatedChan
-		if atomic.Cas(&handlingSig[sig], 0, 1) {
-			atomic.Storeuintptr(&fwdSig[sig], getsig(sig))
-			setsig(sig, abi.FuncPCABIInternal(sighandler))
-		}
-	}
-}
-
-// sigdisable disables the Go signal handler for the signal sig.
-// It is only called while holding the os/signal.handlers lock,
-// via os/signal.disableSignal and signal_disable.
-func sigdisable(sig uint32) {
-	if sig >= uint32(len(sigtable)) {
-		return
-	}
-
-	// SIGPROF is handled specially for profiling.
-	if sig == _SIGPROF {
-		return
-	}
-
-	t := &sigtable[sig]
-	if t.flags&_SigNotify != 0 {
-		ensureSigM()
-		disableSigChan <- sig
-		<-maskUpdatedChan
-
-		// If initsig does not install a signal handler for a
-		// signal, then to go back to the state before Notify
-		// we should remove the one we installed.
-		if !sigInstallGoHandler(sig) {
-			atomic.Store(&handlingSig[sig], 0)
-			setsig(sig, atomic.Loaduintptr(&fwdSig[sig]))
-		}
-	}
-}
-
-// sigignore ignores the signal sig.
-// It is only called while holding the os/signal.handlers lock,
-// via os/signal.ignoreSignal and signal_ignore.
-func sigignore(sig uint32) {
-	if sig >= uint32(len(sigtable)) {
-		return
-	}
-
-	// SIGPROF is handled specially for profiling.
-	if sig == _SIGPROF {
-		return
-	}
-
-	t := &sigtable[sig]
-	if t.flags&_SigNotify != 0 {
-		atomic.Store(&handlingSig[sig], 0)
-		setsig(sig, _SIG_IGN)
-	}
-}
-
-// clearSignalHandlers clears all signal handlers that are not ignored
-// back to the default. This is called by the child after a fork, so that
-// we can enable the signal mask for the exec without worrying about
-// running a signal handler in the child.
-//go:nosplit
-//go:nowritebarrierrec
-func clearSignalHandlers() {
-	for i := uint32(0); i < _NSIG; i++ {
-		if atomic.Load(&handlingSig[i]) != 0 {
-			setsig(i, _SIG_DFL)
-		}
-	}
-}
-
-// setProcessCPUProfilerTimer is called when the profiling timer changes.
-// It is called with prof.signalLock held. hz is the new timer, and is 0 if
-// profiling is being disabled. Enable or disable the signal as
-// required for -buildmode=c-archive.
-func setProcessCPUProfilerTimer(hz int32) {
-	if hz != 0 {
-		// Enable the Go signal handler if not enabled.
-		if atomic.Cas(&handlingSig[_SIGPROF], 0, 1) {
-			h := getsig(_SIGPROF)
-			// If no signal handler was installed before, then we record
-			// _SIG_IGN here. When we turn off profiling (below) we'll start
-			// ignoring SIGPROF signals. We do this, rather than change
-			// to SIG_DFL, because there may be a pending SIGPROF
-			// signal that has not yet been delivered to some other thread.
-			// If we change to SIG_DFL when turning off profiling, the
-			// program will crash when that SIGPROF is delivered. We assume
-			// that programs that use profiling don't want to crash on a
-			// stray SIGPROF. See issue 19320.
-			// We do the change here instead of when turning off profiling,
-			// because there we may race with a signal handler running
-			// concurrently, in particular, sigfwdgo may observe _SIG_DFL and
-			// die. See issue 43828.
-			if h == _SIG_DFL {
-				h = _SIG_IGN
-			}
-			atomic.Storeuintptr(&fwdSig[_SIGPROF], h)
-			setsig(_SIGPROF, abi.FuncPCABIInternal(sighandler))
-		}
-
-		var it itimerval
-		it.it_interval.tv_sec = 0
-		it.it_interval.set_usec(1000000 / hz)
-		it.it_value = it.it_interval
-		setitimer(_ITIMER_PROF, &it, nil)
-	} else {
-		setitimer(_ITIMER_PROF, &itimerval{}, nil)
-
-		// If the Go signal handler should be disabled by default,
-		// switch back to the signal handler that was installed
-		// when we enabled profiling. We don't try to handle the case
-		// of a program that changes the SIGPROF handler while Go
-		// profiling is enabled.
-		if !sigInstallGoHandler(_SIGPROF) {
-			if atomic.Cas(&handlingSig[_SIGPROF], 1, 0) {
-				h := atomic.Loaduintptr(&fwdSig[_SIGPROF])
-				setsig(_SIGPROF, h)
-			}
-		}
-	}
-}
-
-// setThreadCPUProfilerHz makes any thread-specific changes required to
-// implement profiling at a rate of hz.
-// No changes required on Unix systems when using setitimer.
-func setThreadCPUProfilerHz(hz int32) {
-	getg().m.profilehz = hz
-}
-
-func sigpipe() {
-	if signal_ignored(_SIGPIPE) || sigsend(_SIGPIPE) {
-		return
-	}
-	dieFromSignal(_SIGPIPE)
-}
-
-// doSigPreempt handles a preemption signal on gp.
-func doSigPreempt(gp *g, ctxt *sigctxt) {
-	// Check if this G wants to be preempted and is safe to
-	// preempt.
-	if wantAsyncPreempt(gp) {
-		if ok, newpc := isAsyncSafePoint(gp, ctxt.sigpc(), ctxt.sigsp(), ctxt.siglr()); ok {
-			// Adjust the PC and inject a call to asyncPreempt.
-			ctxt.pushCall(abi.FuncPCABI0(asyncPreempt), newpc)
-		}
-	}
-
-	// Acknowledge the preemption.
-	atomic.Xadd(&gp.m.preemptGen, 1)
-	atomic.Store(&gp.m.signalPending, 0)
-
-	if GOOS == "darwin" || GOOS == "ios" {
-		atomic.Xadd(&pendingPreemptSignals, -1)
-	}
-}
-
-const preemptMSupported = true
-
-// preemptM sends a preemption request to mp. This request may be
-// handled asynchronously and may be coalesced with other requests to
-// the M. When the request is received, if the running G or P are
-// marked for preemption and the goroutine is at an asynchronous
-// safe-point, it will preempt the goroutine. It always atomically
-// increments mp.preemptGen after handling a preemption request.
-func preemptM(mp *m) {
-	// On Darwin, don't try to preempt threads during exec.
-	// Issue #41702.
-	if GOOS == "darwin" || GOOS == "ios" {
-		execLock.rlock()
-	}
-
-	if atomic.Cas(&mp.signalPending, 0, 1) {
-		if GOOS == "darwin" || GOOS == "ios" {
-			atomic.Xadd(&pendingPreemptSignals, 1)
-		}
-
-		// If multiple threads are preempting the same M, it may send many
-		// signals to the same M such that it hardly make progress, causing
-		// live-lock problem. Apparently this could happen on darwin. See
-		// issue #37741.
-		// Only send a signal if there isn't already one pending.
-		signalM(mp, sigPreempt)
-	}
-
-	if GOOS == "darwin" || GOOS == "ios" {
-		execLock.runlock()
-	}
-}
-
-// sigFetchG fetches the value of G safely when running in a signal handler.
-// On some architectures, the g value may be clobbered when running in a VDSO.
-// See issue #32912.
-//
-//go:nosplit
-func sigFetchG(c *sigctxt) *g {
-	switch GOARCH {
-	case "arm", "arm64", "ppc64", "ppc64le", "riscv64":
-		if !iscgo && inVDSOPage(c.sigpc()) {
-			// When using cgo, we save the g on TLS and load it from there
-			// in sigtramp. Just use that.
-			// Otherwise, before making a VDSO call we save the g to the
-			// bottom of the signal stack. Fetch from there.
-			// TODO: in efence mode, stack is sysAlloc'd, so this wouldn't
-			// work.
-			sp := getcallersp()
-			s := spanOf(sp)
-			if s != nil && s.state.get() == mSpanManual && s.base() < sp && sp < s.limit {
-				gp := *(**g)(unsafe.Pointer(s.base()))
-				return gp
-			}
-			return nil
-		}
-	}
-	return getg()
-}
-
-// sigtrampgo is called from the signal handler function, sigtramp,
-// written in assembly code.
-// This is called by the signal handler, and the world may be stopped.
-//
-// It must be nosplit because getg() is still the G that was running
-// (if any) when the signal was delivered, but it's (usually) called
-// on the gsignal stack. Until this switches the G to gsignal, the
-// stack bounds check won't work.
-//
-//go:nosplit
-//go:nowritebarrierrec
-func sigtrampgo(sig uint32, info *siginfo, ctx unsafe.Pointer) {
-	if sigfwdgo(sig, info, ctx) {
-		return
-	}
-	c := &sigctxt{info, ctx}
-	g := sigFetchG(c)
-	setg(g)
-	if g == nil {
-		if sig == _SIGPROF {
-			// Some platforms (Linux) have per-thread timers, which we use in
-			// combination with the process-wide timer. Avoid double-counting.
-			if validSIGPROF(nil, c) {
-				sigprofNonGoPC(c.sigpc())
-			}
-			return
-		}
-		if sig == sigPreempt && preemptMSupported && debug.asyncpreemptoff == 0 {
-			// This is probably a signal from preemptM sent
-			// while executing Go code but received while
-			// executing non-Go code.
-			// We got past sigfwdgo, so we know that there is
-			// no non-Go signal handler for sigPreempt.
-			// The default behavior for sigPreempt is to ignore
-			// the signal, so badsignal will be a no-op anyway.
-			if GOOS == "darwin" || GOOS == "ios" {
-				atomic.Xadd(&pendingPreemptSignals, -1)
-			}
-			return
-		}
-		c.fixsigcode(sig)
-		badsignal(uintptr(sig), c)
-		return
-	}
-
-	setg(g.m.gsignal)
-
-	// If some non-Go code called sigaltstack, adjust.
-	var gsignalStack gsignalStack
-	setStack := adjustSignalStack(sig, g.m, &gsignalStack)
-	if setStack {
-		g.m.gsignal.stktopsp = getcallersp()
-	}
-
-	if g.stackguard0 == stackFork {
-		signalDuringFork(sig)
-	}
-
-	c.fixsigcode(sig)
-	sighandler(sig, info, ctx, g)
-	setg(g)
-	if setStack {
-		restoreGsignalStack(&gsignalStack)
-	}
-}
-
-// If the signal handler receives a SIGPROF signal on a non-Go thread,
-// it tries to collect a traceback into sigprofCallers.
-// sigprofCallersUse is set to non-zero while sigprofCallers holds a traceback.
-var sigprofCallers cgoCallers
-var sigprofCallersUse uint32
-
-// sigprofNonGo is called if we receive a SIGPROF signal on a non-Go thread,
-// and the signal handler collected a stack trace in sigprofCallers.
-// When this is called, sigprofCallersUse will be non-zero.
-// g is nil, and what we can do is very limited.
-//
-// It is called from the signal handling functions written in assembly code that
-// are active for cgo programs, cgoSigtramp and sigprofNonGoWrapper, which have
-// not verified that the SIGPROF delivery corresponds to the best available
-// profiling source for this thread.
-//
-//go:nosplit
-//go:nowritebarrierrec
-func sigprofNonGo(sig uint32, info *siginfo, ctx unsafe.Pointer) {
-	if prof.hz != 0 {
-		c := &sigctxt{info, ctx}
-		// Some platforms (Linux) have per-thread timers, which we use in
-		// combination with the process-wide timer. Avoid double-counting.
-		if validSIGPROF(nil, c) {
-			n := 0
-			for n < len(sigprofCallers) && sigprofCallers[n] != 0 {
-				n++
-			}
-			cpuprof.addNonGo(sigprofCallers[:n])
-		}
-	}
-
-	atomic.Store(&sigprofCallersUse, 0)
-}
-
-// sigprofNonGoPC is called when a profiling signal arrived on a
-// non-Go thread and we have a single PC value, not a stack trace.
-// g is nil, and what we can do is very limited.
-//go:nosplit
-//go:nowritebarrierrec
-func sigprofNonGoPC(pc uintptr) {
-	if prof.hz != 0 {
-		stk := []uintptr{
-			pc,
-			abi.FuncPCABIInternal(_ExternalCode) + sys.PCQuantum,
-		}
-		cpuprof.addNonGo(stk)
-	}
-}
-
-// adjustSignalStack adjusts the current stack guard based on the
-// stack pointer that is actually in use while handling a signal.
-// We do this in case some non-Go code called sigaltstack.
-// This reports whether the stack was adjusted, and if so stores the old
-// signal stack in *gsigstack.
-//go:nosplit
-func adjustSignalStack(sig uint32, mp *m, gsigStack *gsignalStack) bool {
-	sp := uintptr(unsafe.Pointer(&sig))
-	if sp >= mp.gsignal.stack.lo && sp < mp.gsignal.stack.hi {
-		return false
-	}
-
-	var st stackt
-	sigaltstack(nil, &st)
-	stsp := uintptr(unsafe.Pointer(st.ss_sp))
-	if st.ss_flags&_SS_DISABLE == 0 && sp >= stsp && sp < stsp+st.ss_size {
-		setGsignalStack(&st, gsigStack)
-		return true
-	}
-
-	if sp >= mp.g0.stack.lo && sp < mp.g0.stack.hi {
-		// The signal was delivered on the g0 stack.
-		// This can happen when linked with C code
-		// using the thread sanitizer, which collects
-		// signals then delivers them itself by calling
-		// the signal handler directly when C code,
-		// including C code called via cgo, calls a
-		// TSAN-intercepted function such as malloc.
-		//
-		// We check this condition last as g0.stack.lo
-		// may be not very accurate (see mstart).
-		st := stackt{ss_size: mp.g0.stack.hi - mp.g0.stack.lo}
-		setSignalstackSP(&st, mp.g0.stack.lo)
-		setGsignalStack(&st, gsigStack)
-		return true
-	}
-
-	// sp is not within gsignal stack, g0 stack, or sigaltstack. Bad.
-	setg(nil)
-	needm()
-	if st.ss_flags&_SS_DISABLE != 0 {
-		noSignalStack(sig)
-	} else {
-		sigNotOnStack(sig)
-	}
-	dropm()
-	return false
-}
-
-// crashing is the number of m's we have waited for when implementing
-// GOTRACEBACK=crash when a signal is received.
-var crashing int32
-
-// testSigtrap and testSigusr1 are used by the runtime tests. If
-// non-nil, it is called on SIGTRAP/SIGUSR1. If it returns true, the
-// normal behavior on this signal is suppressed.
-var testSigtrap func(info *siginfo, ctxt *sigctxt, gp *g) bool
-var testSigusr1 func(gp *g) bool
-
-// sighandler is invoked when a signal occurs. The global g will be
-// set to a gsignal goroutine and we will be running on the alternate
-// signal stack. The parameter g will be the value of the global g
-// when the signal occurred. The sig, info, and ctxt parameters are
-// from the system signal handler: they are the parameters passed when
-// the SA is passed to the sigaction system call.
-//
-// The garbage collector may have stopped the world, so write barriers
-// are not allowed.
-//
-//go:nowritebarrierrec
-func sighandler(sig uint32, info *siginfo, ctxt unsafe.Pointer, gp *g) {
-	_g_ := getg()
-	c := &sigctxt{info, ctxt}
-
-	if sig == _SIGPROF {
-		mp := _g_.m
-		// Some platforms (Linux) have per-thread timers, which we use in
-		// combination with the process-wide timer. Avoid double-counting.
-		if validSIGPROF(mp, c) {
-			sigprof(c.sigpc(), c.sigsp(), c.siglr(), gp, mp)
-		}
-		return
-	}
-
-	if sig == _SIGTRAP && testSigtrap != nil && testSigtrap(info, (*sigctxt)(noescape(unsafe.Pointer(c))), gp) {
-		return
-	}
-
-	if sig == _SIGUSR1 && testSigusr1 != nil && testSigusr1(gp) {
-		return
-	}
-
-	if (GOOS == "linux" || GOOS == "android") && sig == sigPerThreadSyscall {
-		// sigPerThreadSyscall is the same signal used by glibc for
-		// per-thread syscalls on Linux. We use it for the same purpose
-		// in non-cgo binaries. Since this signal is not _SigNotify,
-		// there is nothing more to do once we run the syscall.
-		runPerThreadSyscall()
-		return
-	}
-
-	if sig == sigPreempt && debug.asyncpreemptoff == 0 {
-		// Might be a preemption signal.
-		doSigPreempt(gp, c)
-		// Even if this was definitely a preemption signal, it
-		// may have been coalesced with another signal, so we
-		// still let it through to the application.
-	}
-
-	flags := int32(_SigThrow)
-	if sig < uint32(len(sigtable)) {
-		flags = sigtable[sig].flags
-	}
-	if c.sigcode() != _SI_USER && flags&_SigPanic != 0 && gp.throwsplit {
-		// We can't safely sigpanic because it may grow the
-		// stack. Abort in the signal handler instead.
-		flags = _SigThrow
-	}
-	if isAbortPC(c.sigpc()) {
-		// On many architectures, the abort function just
-		// causes a memory fault. Don't turn that into a panic.
-		flags = _SigThrow
-	}
-	if c.sigcode() != _SI_USER && flags&_SigPanic != 0 {
-		// The signal is going to cause a panic.
-		// Arrange the stack so that it looks like the point
-		// where the signal occurred made a call to the
-		// function sigpanic. Then set the PC to sigpanic.
-
-		// Have to pass arguments out of band since
-		// augmenting the stack frame would break
-		// the unwinding code.
-		gp.sig = sig
-		gp.sigcode0 = uintptr(c.sigcode())
-		gp.sigcode1 = uintptr(c.fault())
-		gp.sigpc = c.sigpc()
-
-		c.preparePanic(sig, gp)
-		return
-	}
-
-	if c.sigcode() == _SI_USER || flags&_SigNotify != 0 {
-		if sigsend(sig) {
-			return
-		}
-	}
-
-	if c.sigcode() == _SI_USER && signal_ignored(sig) {
-		return
-	}
-
-	if flags&_SigKill != 0 {
-		dieFromSignal(sig)
-	}
-
-	// _SigThrow means that we should exit now.
-	// If we get here with _SigPanic, it means that the signal
-	// was sent to us by a program (c.sigcode() == _SI_USER);
-	// in that case, if we didn't handle it in sigsend, we exit now.
-	if flags&(_SigThrow|_SigPanic) == 0 {
-		return
-	}
-
-	_g_.m.throwing = 1
-	_g_.m.caughtsig.set(gp)
-
-	if crashing == 0 {
-		startpanic_m()
-	}
-
-	if sig < uint32(len(sigtable)) {
-		print(sigtable[sig].name, "\n")
-	} else {
-		print("Signal ", sig, "\n")
-	}
-
-	print("PC=", hex(c.sigpc()), " m=", _g_.m.id, " sigcode=", c.sigcode(), "\n")
-	if _g_.m.incgo && gp == _g_.m.g0 && _g_.m.curg != nil {
-		print("signal arrived during cgo execution\n")
-		// Switch to curg so that we get a traceback of the Go code
-		// leading up to the cgocall, which switched from curg to g0.
-		gp = _g_.m.curg
-	}
-	if sig == _SIGILL || sig == _SIGFPE {
-		// It would be nice to know how long the instruction is.
-		// Unfortunately, that's complicated to do in general (mostly for x86
-		// and s930x, but other archs have non-standard instruction lengths also).
-		// Opt to print 16 bytes, which covers most instructions.
-		const maxN = 16
-		n := uintptr(maxN)
-		// We have to be careful, though. If we're near the end of
-		// a page and the following page isn't mapped, we could
-		// segfault. So make sure we don't straddle a page (even though
-		// that could lead to printing an incomplete instruction).
-		// We're assuming here we can read at least the page containing the PC.
-		// I suppose it is possible that the page is mapped executable but not readable?
-		pc := c.sigpc()
-		if n > physPageSize-pc%physPageSize {
-			n = physPageSize - pc%physPageSize
-		}
-		print("instruction bytes:")
-		b := (*[maxN]byte)(unsafe.Pointer(pc))
-		for i := uintptr(0); i < n; i++ {
-			print(" ", hex(b[i]))
-		}
-		println()
-	}
-	print("\n")
-
-	level, _, docrash := gotraceback()
-	if level > 0 {
-		goroutineheader(gp)
-		tracebacktrap(c.sigpc(), c.sigsp(), c.siglr(), gp)
-		if crashing > 0 && gp != _g_.m.curg && _g_.m.curg != nil && readgstatus(_g_.m.curg)&^_Gscan == _Grunning {
-			// tracebackothers on original m skipped this one; trace it now.
-			goroutineheader(_g_.m.curg)
-			traceback(^uintptr(0), ^uintptr(0), 0, _g_.m.curg)
-		} else if crashing == 0 {
-			tracebackothers(gp)
-			print("\n")
-		}
-		dumpregs(c)
-	}
-
-	if docrash {
-		crashing++
-		if crashing < mcount()-int32(extraMCount) {
-			// There are other m's that need to dump their stacks.
-			// Relay SIGQUIT to the next m by sending it to the current process.
-			// All m's that have already received SIGQUIT have signal masks blocking
-			// receipt of any signals, so the SIGQUIT will go to an m that hasn't seen it yet.
-			// When the last m receives the SIGQUIT, it will fall through to the call to
-			// crash below. Just in case the relaying gets botched, each m involved in
-			// the relay sleeps for 5 seconds and then does the crash/exit itself.
-			// In expected operation, the last m has received the SIGQUIT and run
-			// crash/exit and the process is gone, all long before any of the
-			// 5-second sleeps have finished.
-			print("\n-----\n\n")
-			raiseproc(_SIGQUIT)
-			usleep(5 * 1000 * 1000)
-		}
-		crash()
-	}
-
-	printDebugLog()
-
-	exit(2)
-}
-
-// sigpanic turns a synchronous signal into a run-time panic.
-// If the signal handler sees a synchronous panic, it arranges the
-// stack to look like the function where the signal occurred called
-// sigpanic, sets the signal's PC value to sigpanic, and returns from
-// the signal handler. The effect is that the program will act as
-// though the function that got the signal simply called sigpanic
-// instead.
-//
-// This must NOT be nosplit because the linker doesn't know where
-// sigpanic calls can be injected.
-//
-// The signal handler must not inject a call to sigpanic if
-// getg().throwsplit, since sigpanic may need to grow the stack.
-//
-// This is exported via linkname to assembly in runtime/cgo.
-//go:linkname sigpanic
-func sigpanic() {
-	g := getg()
-	if !canpanic(g) {
-		throw("unexpected signal during runtime execution")
-	}
-
-	switch g.sig {
-	case _SIGBUS:
-		if g.sigcode0 == _BUS_ADRERR && g.sigcode1 < 0x1000 {
-			panicmem()
-		}
-		// Support runtime/debug.SetPanicOnFault.
-		if g.paniconfault {
-			panicmemAddr(g.sigcode1)
-		}
-		print("unexpected fault address ", hex(g.sigcode1), "\n")
-		throw("fault")
-	case _SIGSEGV:
-		if (g.sigcode0 == 0 || g.sigcode0 == _SEGV_MAPERR || g.sigcode0 == _SEGV_ACCERR) && g.sigcode1 < 0x1000 {
-			panicmem()
-		}
-		// Support runtime/debug.SetPanicOnFault.
-		if g.paniconfault {
-			panicmemAddr(g.sigcode1)
-		}
-		print("unexpected fault address ", hex(g.sigcode1), "\n")
-		throw("fault")
-	case _SIGFPE:
-		switch g.sigcode0 {
-		case _FPE_INTDIV:
-			panicdivide()
-		case _FPE_INTOVF:
-			panicoverflow()
-		}
-		panicfloat()
-	}
-
-	if g.sig >= uint32(len(sigtable)) {
-		// can't happen: we looked up g.sig in sigtable to decide to call sigpanic
-		throw("unexpected signal value")
-	}
-	panic(errorString(sigtable[g.sig].name))
-}
-
-// dieFromSignal kills the program with a signal.
-// This provides the expected exit status for the shell.
-// This is only called with fatal signals expected to kill the process.
-//go:nosplit
-//go:nowritebarrierrec
-func dieFromSignal(sig uint32) {
-	unblocksig(sig)
-	// Mark the signal as unhandled to ensure it is forwarded.
-	atomic.Store(&handlingSig[sig], 0)
-	raise(sig)
-
-	// That should have killed us. On some systems, though, raise
-	// sends the signal to the whole process rather than to just
-	// the current thread, which means that the signal may not yet
-	// have been delivered. Give other threads a chance to run and
-	// pick up the signal.
-	osyield()
-	osyield()
-	osyield()
-
-	// If that didn't work, try _SIG_DFL.
-	setsig(sig, _SIG_DFL)
-	raise(sig)
-
-	osyield()
-	osyield()
-	osyield()
-
-	// If we are still somehow running, just exit with the wrong status.
-	exit(2)
-}
-
-// raisebadsignal is called when a signal is received on a non-Go
-// thread, and the Go program does not want to handle it (that is, the
-// program has not called os/signal.Notify for the signal).
-func raisebadsignal(sig uint32, c *sigctxt) {
-	if sig == _SIGPROF {
-		// Ignore profiling signals that arrive on non-Go threads.
-		return
-	}
-
-	var handler uintptr
-	if sig >= _NSIG {
-		handler = _SIG_DFL
-	} else {
-		handler = atomic.Loaduintptr(&fwdSig[sig])
-	}
-
-	// Reset the signal handler and raise the signal.
-	// We are currently running inside a signal handler, so the
-	// signal is blocked. We need to unblock it before raising the
-	// signal, or the signal we raise will be ignored until we return
-	// from the signal handler. We know that the signal was unblocked
-	// before entering the handler, or else we would not have received
-	// it. That means that we don't have to worry about blocking it
-	// again.
-	unblocksig(sig)
-	setsig(sig, handler)
-
-	// If we're linked into a non-Go program we want to try to
-	// avoid modifying the original context in which the signal
-	// was raised. If the handler is the default, we know it
-	// is non-recoverable, so we don't have to worry about
-	// re-installing sighandler. At this point we can just
-	// return and the signal will be re-raised and caught by
-	// the default handler with the correct context.
-	//
-	// On FreeBSD, the libthr sigaction code prevents
-	// this from working so we fall through to raise.
-	if GOOS != "freebsd" && (isarchive || islibrary) && handler == _SIG_DFL && c.sigcode() != _SI_USER {
-		return
-	}
-
-	raise(sig)
-
-	// Give the signal a chance to be delivered.
-	// In almost all real cases the program is about to crash,
-	// so sleeping here is not a waste of time.
-	usleep(1000)
-
-	// If the signal didn't cause the program to exit, restore the
-	// Go signal handler and carry on.
-	//
-	// We may receive another instance of the signal before we
-	// restore the Go handler, but that is not so bad: we know
-	// that the Go program has been ignoring the signal.
-	setsig(sig, abi.FuncPCABIInternal(sighandler))
-}
-
-//go:nosplit
-func crash() {
-	// OS X core dumps are linear dumps of the mapped memory,
-	// from the first virtual byte to the last, with zeros in the gaps.
-	// Because of the way we arrange the address space on 64-bit systems,
-	// this means the OS X core file will be >128 GB and even on a zippy
-	// workstation can take OS X well over an hour to write (uninterruptible).
-	// Save users from making that mistake.
-	if GOOS == "darwin" && GOARCH == "amd64" {
-		return
-	}
-
-	dieFromSignal(_SIGABRT)
-}
-
-// ensureSigM starts one global, sleeping thread to make sure at least one thread
-// is available to catch signals enabled for os/signal.
-func ensureSigM() {
-	if maskUpdatedChan != nil {
-		return
-	}
-	maskUpdatedChan = make(chan struct{})
-	disableSigChan = make(chan uint32)
-	enableSigChan = make(chan uint32)
-	go func() {
-		// Signal masks are per-thread, so make sure this goroutine stays on one
-		// thread.
-		LockOSThread()
-		defer UnlockOSThread()
-		// The sigBlocked mask contains the signals not active for os/signal,
-		// initially all signals except the essential. When signal.Notify()/Stop is called,
-		// sigenable/sigdisable in turn notify this thread to update its signal
-		// mask accordingly.
-		sigBlocked := sigset_all
-		for i := range sigtable {
-			if !blockableSig(uint32(i)) {
-				sigdelset(&sigBlocked, i)
-			}
-		}
-		sigprocmask(_SIG_SETMASK, &sigBlocked, nil)
-		for {
-			select {
-			case sig := <-enableSigChan:
-				if sig > 0 {
-					sigdelset(&sigBlocked, int(sig))
-				}
-			case sig := <-disableSigChan:
-				if sig > 0 && blockableSig(sig) {
-					sigaddset(&sigBlocked, int(sig))
-				}
-			}
-			sigprocmask(_SIG_SETMASK, &sigBlocked, nil)
-			maskUpdatedChan <- struct{}{}
-		}
-	}()
-}
-
-// This is called when we receive a signal when there is no signal stack.
-// This can only happen if non-Go code calls sigaltstack to disable the
-// signal stack.
-func noSignalStack(sig uint32) {
-	println("signal", sig, "received on thread with no signal stack")
-	throw("non-Go code disabled sigaltstack")
-}
-
-// This is called if we receive a signal when there is a signal stack
-// but we are not on it. This can only happen if non-Go code called
-// sigaction without setting the SS_ONSTACK flag.
-func sigNotOnStack(sig uint32) {
-	println("signal", sig, "received but handler not on signal stack")
-	throw("non-Go code set up signal handler without SA_ONSTACK flag")
-}
-
-// signalDuringFork is called if we receive a signal while doing a fork.
-// We do not want signals at that time, as a signal sent to the process
-// group may be delivered to the child process, causing confusion.
-// This should never be called, because we block signals across the fork;
-// this function is just a safety check. See issue 18600 for background.
-func signalDuringFork(sig uint32) {
-	println("signal", sig, "received during fork")
-	throw("signal received during fork")
-}
-
-var badginsignalMsg = "fatal: bad g in signal handler\n"
-
-// This runs on a foreign stack, without an m or a g. No stack split.
-//go:nosplit
-//go:norace
-//go:nowritebarrierrec
-func badsignal(sig uintptr, c *sigctxt) {
-	if !iscgo && !cgoHasExtraM {
-		// There is no extra M. needm will not be able to grab
-		// an M. Instead of hanging, just crash.
-		// Cannot call split-stack function as there is no G.
-		s := stringStructOf(&badginsignalMsg)
-		write(2, s.str, int32(s.len))
-		exit(2)
-		*(*uintptr)(unsafe.Pointer(uintptr(123))) = 2
-	}
-	needm()
-	if !sigsend(uint32(sig)) {
-		// A foreign thread received the signal sig, and the
-		// Go code does not want to handle it.
-		raisebadsignal(uint32(sig), c)
-	}
-	dropm()
-}
-
-//go:noescape
-func sigfwd(fn uintptr, sig uint32, info *siginfo, ctx unsafe.Pointer)
-
-// Determines if the signal should be handled by Go and if not, forwards the
-// signal to the handler that was installed before Go's. Returns whether the
-// signal was forwarded.
-// This is called by the signal handler, and the world may be stopped.
-//go:nosplit
-//go:nowritebarrierrec
-func sigfwdgo(sig uint32, info *siginfo, ctx unsafe.Pointer) bool {
-	if sig >= uint32(len(sigtable)) {
-		return false
-	}
-	fwdFn := atomic.Loaduintptr(&fwdSig[sig])
-	flags := sigtable[sig].flags
-
-	// If we aren't handling the signal, forward it.
-	if atomic.Load(&handlingSig[sig]) == 0 || !signalsOK {
-		// If the signal is ignored, doing nothing is the same as forwarding.
-		if fwdFn == _SIG_IGN || (fwdFn == _SIG_DFL && flags&_SigIgn != 0) {
-			return true
-		}
-		// We are not handling the signal and there is no other handler to forward to.
-		// Crash with the default behavior.
-		if fwdFn == _SIG_DFL {
-			setsig(sig, _SIG_DFL)
-			dieFromSignal(sig)
-			return false
-		}
-
-		sigfwd(fwdFn, sig, info, ctx)
-		return true
-	}
-
-	// This function and its caller sigtrampgo assumes SIGPIPE is delivered on the
-	// originating thread. This property does not hold on macOS (golang.org/issue/33384),
-	// so we have no choice but to ignore SIGPIPE.
-	if (GOOS == "darwin" || GOOS == "ios") && sig == _SIGPIPE {
-		return true
-	}
-
-	// If there is no handler to forward to, no need to forward.
-	if fwdFn == _SIG_DFL {
-		return false
-	}
-
-	c := &sigctxt{info, ctx}
-	// Only forward synchronous signals and SIGPIPE.
-	// Unfortunately, user generated SIGPIPEs will also be forwarded, because si_code
-	// is set to _SI_USER even for a SIGPIPE raised from a write to a closed socket
-	// or pipe.
-	if (c.sigcode() == _SI_USER || flags&_SigPanic == 0) && sig != _SIGPIPE {
-		return false
-	}
-	// Determine if the signal occurred inside Go code. We test that:
-	//   (1) we weren't in VDSO page,
-	//   (2) we were in a goroutine (i.e., m.curg != nil), and
-	//   (3) we weren't in CGO.
-	g := sigFetchG(c)
-	if g != nil && g.m != nil && g.m.curg != nil && !g.m.incgo {
-		return false
-	}
-
-	// Signal not handled by Go, forward it.
-	if fwdFn != _SIG_IGN {
-		sigfwd(fwdFn, sig, info, ctx)
-	}
-
-	return true
-}
-
-// sigsave saves the current thread's signal mask into *p.
-// This is used to preserve the non-Go signal mask when a non-Go
-// thread calls a Go function.
-// This is nosplit and nowritebarrierrec because it is called by needm
-// which may be called on a non-Go thread with no g available.
-//go:nosplit
-//go:nowritebarrierrec
-func sigsave(p *sigset) {
-	sigprocmask(_SIG_SETMASK, nil, p)
-}
-
-// msigrestore sets the current thread's signal mask to sigmask.
-// This is used to restore the non-Go signal mask when a non-Go thread
-// calls a Go function.
-// This is nosplit and nowritebarrierrec because it is called by dropm
-// after g has been cleared.
-//go:nosplit
-//go:nowritebarrierrec
-func msigrestore(sigmask sigset) {
-	sigprocmask(_SIG_SETMASK, &sigmask, nil)
-}
-
-// sigsetAllExiting is used by sigblock(true) when a thread is
-// exiting. sigset_all is defined in OS specific code, and per GOOS
-// behavior may override this default for sigsetAllExiting: see
-// osinit().
-var sigsetAllExiting = sigset_all
-
-// sigblock blocks signals in the current thread's signal mask.
-// This is used to block signals while setting up and tearing down g
-// when a non-Go thread calls a Go function. When a thread is exiting
-// we use the sigsetAllExiting value, otherwise the OS specific
-// definition of sigset_all is used.
-// This is nosplit and nowritebarrierrec because it is called by needm
-// which may be called on a non-Go thread with no g available.
-//go:nosplit
-//go:nowritebarrierrec
-func sigblock(exiting bool) {
-	if exiting {
-		sigprocmask(_SIG_SETMASK, &sigsetAllExiting, nil)
-		return
-	}
-	sigprocmask(_SIG_SETMASK, &sigset_all, nil)
-}
-
-// unblocksig removes sig from the current thread's signal mask.
-// This is nosplit and nowritebarrierrec because it is called from
-// dieFromSignal, which can be called by sigfwdgo while running in the
-// signal handler, on the signal stack, with no g available.
-//go:nosplit
-//go:nowritebarrierrec
-func unblocksig(sig uint32) {
-	var set sigset
-	sigaddset(&set, int(sig))
-	sigprocmask(_SIG_UNBLOCK, &set, nil)
-}
-
-// minitSignals is called when initializing a new m to set the
-// thread's alternate signal stack and signal mask.
-func minitSignals() {
-	minitSignalStack()
-	minitSignalMask()
-}
-
-// minitSignalStack is called when initializing a new m to set the
-// alternate signal stack. If the alternate signal stack is not set
-// for the thread (the normal case) then set the alternate signal
-// stack to the gsignal stack. If the alternate signal stack is set
-// for the thread (the case when a non-Go thread sets the alternate
-// signal stack and then calls a Go function) then set the gsignal
-// stack to the alternate signal stack. We also set the alternate
-// signal stack to the gsignal stack if cgo is not used (regardless
-// of whether it is already set). Record which choice was made in
-// newSigstack, so that it can be undone in unminit.
-func minitSignalStack() {
-	_g_ := getg()
-	var st stackt
-	sigaltstack(nil, &st)
-	if st.ss_flags&_SS_DISABLE != 0 || !iscgo {
-		signalstack(&_g_.m.gsignal.stack)
-		_g_.m.newSigstack = true
-	} else {
-		setGsignalStack(&st, &_g_.m.goSigStack)
-		_g_.m.newSigstack = false
-	}
-}
-
-// minitSignalMask is called when initializing a new m to set the
-// thread's signal mask. When this is called all signals have been
-// blocked for the thread.  This starts with m.sigmask, which was set
-// either from initSigmask for a newly created thread or by calling
-// sigsave if this is a non-Go thread calling a Go function. It
-// removes all essential signals from the mask, thus causing those
-// signals to not be blocked. Then it sets the thread's signal mask.
-// After this is called the thread can receive signals.
-func minitSignalMask() {
-	nmask := getg().m.sigmask
-	for i := range sigtable {
-		if !blockableSig(uint32(i)) {
-			sigdelset(&nmask, i)
-		}
-	}
-	sigprocmask(_SIG_SETMASK, &nmask, nil)
-}
-
-// unminitSignals is called from dropm, via unminit, to undo the
-// effect of calling minit on a non-Go thread.
-//go:nosplit
-func unminitSignals() {
-	if getg().m.newSigstack {
-		st := stackt{ss_flags: _SS_DISABLE}
-		sigaltstack(&st, nil)
-	} else {
-		// We got the signal stack from someone else. Restore
-		// the Go-allocated stack in case this M gets reused
-		// for another thread (e.g., it's an extram). Also, on
-		// Android, libc allocates a signal stack for all
-		// threads, so it's important to restore the Go stack
-		// even on Go-created threads so we can free it.
-		restoreGsignalStack(&getg().m.goSigStack)
-	}
-}
-
-// blockableSig reports whether sig may be blocked by the signal mask.
-// We never want to block the signals marked _SigUnblock;
-// these are the synchronous signals that turn into a Go panic.
-// We never want to block the preemption signal if it is being used.
-// In a Go program--not a c-archive/c-shared--we never want to block
-// the signals marked _SigKill or _SigThrow, as otherwise it's possible
-// for all running threads to block them and delay their delivery until
-// we start a new thread. When linked into a C program we let the C code
-// decide on the disposition of those signals.
-func blockableSig(sig uint32) bool {
-	flags := sigtable[sig].flags
-	if flags&_SigUnblock != 0 {
-		return false
-	}
-	if sig == sigPreempt && preemptMSupported && debug.asyncpreemptoff == 0 {
-		return false
-	}
-	if isarchive || islibrary {
-		return true
-	}
-	return flags&(_SigKill|_SigThrow) == 0
-}
-
-// gsignalStack saves the fields of the gsignal stack changed by
-// setGsignalStack.
-type gsignalStack struct {
-	stack       stack
-	stackguard0 uintptr
-	stackguard1 uintptr
-	stktopsp    uintptr
-}
-
-// setGsignalStack sets the gsignal stack of the current m to an
-// alternate signal stack returned from the sigaltstack system call.
-// It saves the old values in *old for use by restoreGsignalStack.
-// This is used when handling a signal if non-Go code has set the
-// alternate signal stack.
-//go:nosplit
-//go:nowritebarrierrec
-func setGsignalStack(st *stackt, old *gsignalStack) {
-	g := getg()
-	if old != nil {
-		old.stack = g.m.gsignal.stack
-		old.stackguard0 = g.m.gsignal.stackguard0
-		old.stackguard1 = g.m.gsignal.stackguard1
-		old.stktopsp = g.m.gsignal.stktopsp
-	}
-	stsp := uintptr(unsafe.Pointer(st.ss_sp))
-	g.m.gsignal.stack.lo = stsp
-	g.m.gsignal.stack.hi = stsp + st.ss_size
-	g.m.gsignal.stackguard0 = stsp + _StackGuard
-	g.m.gsignal.stackguard1 = stsp + _StackGuard
-}
-
-// restoreGsignalStack restores the gsignal stack to the value it had
-// before entering the signal handler.
-//go:nosplit
-//go:nowritebarrierrec
-func restoreGsignalStack(st *gsignalStack) {
-	gp := getg().m.gsignal
-	gp.stack = st.stack
-	gp.stackguard0 = st.stackguard0
-	gp.stackguard1 = st.stackguard1
-	gp.stktopsp = st.stktopsp
-}
-
-// signalstack sets the current thread's alternate signal stack to s.
-//go:nosplit
-func signalstack(s *stack) {
-	st := stackt{ss_size: s.hi - s.lo}
-	setSignalstackSP(&st, s.lo)
-	sigaltstack(&st, nil)
-}
-
-// setsigsegv is used on darwin/arm64 to fake a segmentation fault.
-//
-// This is exported via linkname to assembly in runtime/cgo.
-//
-//go:nosplit
-//go:linkname setsigsegv
-func setsigsegv(pc uintptr) {
-	g := getg()
-	g.sig = _SIGSEGV
-	g.sigpc = pc
-	g.sigcode0 = _SEGV_MAPERR
-	g.sigcode1 = 0 // TODO: emulate si_addr
-}
diff --git a/contrib/go/_std_1.18/src/runtime/sigqueue.go b/contrib/go/_std_1.18/src/runtime/sigqueue.go
deleted file mode 100644
index fdf99d94a2..0000000000
--- a/contrib/go/_std_1.18/src/runtime/sigqueue.go
+++ /dev/null
@@ -1,268 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file implements runtime support for signal handling.
-//
-// Most synchronization primitives are not available from
-// the signal handler (it cannot block, allocate memory, or use locks)
-// so the handler communicates with a processing goroutine
-// via struct sig, below.
-//
-// sigsend is called by the signal handler to queue a new signal.
-// signal_recv is called by the Go program to receive a newly queued signal.
-//
-// Synchronization between sigsend and signal_recv is based on the sig.state
-// variable. It can be in three states:
-// * sigReceiving means that signal_recv is blocked on sig.Note and there are
-//   no new pending signals.
-// * sigSending means that sig.mask *may* contain new pending signals,
-//   signal_recv can't be blocked in this state.
-// * sigIdle means that there are no new pending signals and signal_recv is not
-//   blocked.
-//
-// Transitions between states are done atomically with CAS.
-//
-// When signal_recv is unblocked, it resets sig.Note and rechecks sig.mask.
-// If several sigsends and signal_recv execute concurrently, it can lead to
-// unnecessary rechecks of sig.mask, but it cannot lead to missed signals
-// nor deadlocks.
-
-//go:build !plan9
-
-package runtime
-
-import (
-	"runtime/internal/atomic"
-	_ "unsafe" // for go:linkname
-)
-
-// sig handles communication between the signal handler and os/signal.
-// Other than the inuse and recv fields, the fields are accessed atomically.
-//
-// The wanted and ignored fields are only written by one goroutine at
-// a time; access is controlled by the handlers Mutex in os/signal.
-// The fields are only read by that one goroutine and by the signal handler.
-// We access them atomically to minimize the race between setting them
-// in the goroutine calling os/signal and the signal handler,
-// which may be running in a different thread. That race is unavoidable,
-// as there is no connection between handling a signal and receiving one,
-// but atomic instructions should minimize it.
-var sig struct {
-	note       note
-	mask       [(_NSIG + 31) / 32]uint32
-	wanted     [(_NSIG + 31) / 32]uint32
-	ignored    [(_NSIG + 31) / 32]uint32
-	recv       [(_NSIG + 31) / 32]uint32
-	state      uint32
-	delivering uint32
-	inuse      bool
-}
-
-const (
-	sigIdle = iota
-	sigReceiving
-	sigSending
-)
-
-// sigsend delivers a signal from sighandler to the internal signal delivery queue.
-// It reports whether the signal was sent. If not, the caller typically crashes the program.
-// It runs from the signal handler, so it's limited in what it can do.
-func sigsend(s uint32) bool {
-	bit := uint32(1) << uint(s&31)
-	if s >= uint32(32*len(sig.wanted)) {
-		return false
-	}
-
-	atomic.Xadd(&sig.delivering, 1)
-	// We are running in the signal handler; defer is not available.
-
-	if w := atomic.Load(&sig.wanted[s/32]); w&bit == 0 {
-		atomic.Xadd(&sig.delivering, -1)
-		return false
-	}
-
-	// Add signal to outgoing queue.
-	for {
-		mask := sig.mask[s/32]
-		if mask&bit != 0 {
-			atomic.Xadd(&sig.delivering, -1)
-			return true // signal already in queue
-		}
-		if atomic.Cas(&sig.mask[s/32], mask, mask|bit) {
-			break
-		}
-	}
-
-	// Notify receiver that queue has new bit.
-Send:
-	for {
-		switch atomic.Load(&sig.state) {
-		default:
-			throw("sigsend: inconsistent state")
-		case sigIdle:
-			if atomic.Cas(&sig.state, sigIdle, sigSending) {
-				break Send
-			}
-		case sigSending:
-			// notification already pending
-			break Send
-		case sigReceiving:
-			if atomic.Cas(&sig.state, sigReceiving, sigIdle) {
-				if GOOS == "darwin" || GOOS == "ios" {
-					sigNoteWakeup(&sig.note)
-					break Send
-				}
-				notewakeup(&sig.note)
-				break Send
-			}
-		}
-	}
-
-	atomic.Xadd(&sig.delivering, -1)
-	return true
-}
-
-// Called to receive the next queued signal.
-// Must only be called from a single goroutine at a time.
-//go:linkname signal_recv os/signal.signal_recv
-func signal_recv() uint32 {
-	for {
-		// Serve any signals from local copy.
-		for i := uint32(0); i < _NSIG; i++ {
-			if sig.recv[i/32]&(1<<(i&31)) != 0 {
-				sig.recv[i/32] &^= 1 << (i & 31)
-				return i
-			}
-		}
-
-		// Wait for updates to be available from signal sender.
-	Receive:
-		for {
-			switch atomic.Load(&sig.state) {
-			default:
-				throw("signal_recv: inconsistent state")
-			case sigIdle:
-				if atomic.Cas(&sig.state, sigIdle, sigReceiving) {
-					if GOOS == "darwin" || GOOS == "ios" {
-						sigNoteSleep(&sig.note)
-						break Receive
-					}
-					notetsleepg(&sig.note, -1)
-					noteclear(&sig.note)
-					break Receive
-				}
-			case sigSending:
-				if atomic.Cas(&sig.state, sigSending, sigIdle) {
-					break Receive
-				}
-			}
-		}
-
-		// Incorporate updates from sender into local copy.
-		for i := range sig.mask {
-			sig.recv[i] = atomic.Xchg(&sig.mask[i], 0)
-		}
-	}
-}
-
-// signalWaitUntilIdle waits until the signal delivery mechanism is idle.
-// This is used to ensure that we do not drop a signal notification due
-// to a race between disabling a signal and receiving a signal.
-// This assumes that signal delivery has already been disabled for
-// the signal(s) in question, and here we are just waiting to make sure
-// that all the signals have been delivered to the user channels
-// by the os/signal package.
-//go:linkname signalWaitUntilIdle os/signal.signalWaitUntilIdle
-func signalWaitUntilIdle() {
-	// Although the signals we care about have been removed from
-	// sig.wanted, it is possible that another thread has received
-	// a signal, has read from sig.wanted, is now updating sig.mask,
-	// and has not yet woken up the processor thread. We need to wait
-	// until all current signal deliveries have completed.
-	for atomic.Load(&sig.delivering) != 0 {
-		Gosched()
-	}
-
-	// Although WaitUntilIdle seems like the right name for this
-	// function, the state we are looking for is sigReceiving, not
-	// sigIdle.  The sigIdle state is really more like sigProcessing.
-	for atomic.Load(&sig.state) != sigReceiving {
-		Gosched()
-	}
-}
-
-// Must only be called from a single goroutine at a time.
-//go:linkname signal_enable os/signal.signal_enable
-func signal_enable(s uint32) {
-	if !sig.inuse {
-		// This is the first call to signal_enable. Initialize.
-		sig.inuse = true // enable reception of signals; cannot disable
-		if GOOS == "darwin" || GOOS == "ios" {
-			sigNoteSetup(&sig.note)
-		} else {
-			noteclear(&sig.note)
-		}
-	}
-
-	if s >= uint32(len(sig.wanted)*32) {
-		return
-	}
-
-	w := sig.wanted[s/32]
-	w |= 1 << (s & 31)
-	atomic.Store(&sig.wanted[s/32], w)
-
-	i := sig.ignored[s/32]
-	i &^= 1 << (s & 31)
-	atomic.Store(&sig.ignored[s/32], i)
-
-	sigenable(s)
-}
-
-// Must only be called from a single goroutine at a time.
-//go:linkname signal_disable os/signal.signal_disable
-func signal_disable(s uint32) {
-	if s >= uint32(len(sig.wanted)*32) {
-		return
-	}
-	sigdisable(s)
-
-	w := sig.wanted[s/32]
-	w &^= 1 << (s & 31)
-	atomic.Store(&sig.wanted[s/32], w)
-}
-
-// Must only be called from a single goroutine at a time.
-//go:linkname signal_ignore os/signal.signal_ignore
-func signal_ignore(s uint32) {
-	if s >= uint32(len(sig.wanted)*32) {
-		return
-	}
-	sigignore(s)
-
-	w := sig.wanted[s/32]
-	w &^= 1 << (s & 31)
-	atomic.Store(&sig.wanted[s/32], w)
-
-	i := sig.ignored[s/32]
-	i |= 1 << (s & 31)
-	atomic.Store(&sig.ignored[s/32], i)
-}
-
-// sigInitIgnored marks the signal as already ignored. This is called at
-// program start by initsig. In a shared library initsig is called by
-// libpreinit, so the runtime may not be initialized yet.
-//go:nosplit
-func sigInitIgnored(s uint32) {
-	i := sig.ignored[s/32]
-	i |= 1 << (s & 31)
-	atomic.Store(&sig.ignored[s/32], i)
-}
-
-// Checked by signal handlers.
-//go:linkname signal_ignored os/signal.signal_ignored
-func signal_ignored(s uint32) bool {
-	i := atomic.Load(&sig.ignored[s/32])
-	return i&(1<<(s&31)) != 0
-}
diff --git a/contrib/go/_std_1.18/src/runtime/slice.go b/contrib/go/_std_1.18/src/runtime/slice.go
deleted file mode 100644
index e0aeba604f..0000000000
--- a/contrib/go/_std_1.18/src/runtime/slice.go
+++ /dev/null
@@ -1,332 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"internal/abi"
-	"internal/goarch"
-	"runtime/internal/math"
-	"runtime/internal/sys"
-	"unsafe"
-)
-
-type slice struct {
-	array unsafe.Pointer
-	len   int
-	cap   int
-}
-
-// A notInHeapSlice is a slice backed by go:notinheap memory.
-type notInHeapSlice struct {
-	array *notInHeap
-	len   int
-	cap   int
-}
-
-func panicmakeslicelen() {
-	panic(errorString("makeslice: len out of range"))
-}
-
-func panicmakeslicecap() {
-	panic(errorString("makeslice: cap out of range"))
-}
-
-// makeslicecopy allocates a slice of "tolen" elements of type "et",
-// then copies "fromlen" elements of type "et" into that new allocation from "from".
-func makeslicecopy(et *_type, tolen int, fromlen int, from unsafe.Pointer) unsafe.Pointer {
-	var tomem, copymem uintptr
-	if uintptr(tolen) > uintptr(fromlen) {
-		var overflow bool
-		tomem, overflow = math.MulUintptr(et.size, uintptr(tolen))
-		if overflow || tomem > maxAlloc || tolen < 0 {
-			panicmakeslicelen()
-		}
-		copymem = et.size * uintptr(fromlen)
-	} else {
-		// fromlen is a known good length providing and equal or greater than tolen,
-		// thereby making tolen a good slice length too as from and to slices have the
-		// same element width.
-		tomem = et.size * uintptr(tolen)
-		copymem = tomem
-	}
-
-	var to unsafe.Pointer
-	if et.ptrdata == 0 {
-		to = mallocgc(tomem, nil, false)
-		if copymem < tomem {
-			memclrNoHeapPointers(add(to, copymem), tomem-copymem)
-		}
-	} else {
-		// Note: can't use rawmem (which avoids zeroing of memory), because then GC can scan uninitialized memory.
-		to = mallocgc(tomem, et, true)
-		if copymem > 0 && writeBarrier.enabled {
-			// Only shade the pointers in old.array since we know the destination slice to
-			// only contains nil pointers because it has been cleared during alloc.
-			bulkBarrierPreWriteSrcOnly(uintptr(to), uintptr(from), copymem)
-		}
-	}
-
-	if raceenabled {
-		callerpc := getcallerpc()
-		pc := abi.FuncPCABIInternal(makeslicecopy)
-		racereadrangepc(from, copymem, callerpc, pc)
-	}
-	if msanenabled {
-		msanread(from, copymem)
-	}
-	if asanenabled {
-		asanread(from, copymem)
-	}
-
-	memmove(to, from, copymem)
-
-	return to
-}
-
-func makeslice(et *_type, len, cap int) unsafe.Pointer {
-	mem, overflow := math.MulUintptr(et.size, uintptr(cap))
-	if overflow || mem > maxAlloc || len < 0 || len > cap {
-		// NOTE: Produce a 'len out of range' error instead of a
-		// 'cap out of range' error when someone does make([]T, bignumber).
-		// 'cap out of range' is true too, but since the cap is only being
-		// supplied implicitly, saying len is clearer.
-		// See golang.org/issue/4085.
-		mem, overflow := math.MulUintptr(et.size, uintptr(len))
-		if overflow || mem > maxAlloc || len < 0 {
-			panicmakeslicelen()
-		}
-		panicmakeslicecap()
-	}
-
-	return mallocgc(mem, et, true)
-}
-
-func makeslice64(et *_type, len64, cap64 int64) unsafe.Pointer {
-	len := int(len64)
-	if int64(len) != len64 {
-		panicmakeslicelen()
-	}
-
-	cap := int(cap64)
-	if int64(cap) != cap64 {
-		panicmakeslicecap()
-	}
-
-	return makeslice(et, len, cap)
-}
-
-func unsafeslice(et *_type, ptr unsafe.Pointer, len int) {
-	if len < 0 {
-		panicunsafeslicelen()
-	}
-
-	mem, overflow := math.MulUintptr(et.size, uintptr(len))
-	if overflow || mem > -uintptr(ptr) {
-		if ptr == nil {
-			panic(errorString("unsafe.Slice: ptr is nil and len is not zero"))
-		}
-		panicunsafeslicelen()
-	}
-}
-
-func unsafeslice64(et *_type, ptr unsafe.Pointer, len64 int64) {
-	len := int(len64)
-	if int64(len) != len64 {
-		panicunsafeslicelen()
-	}
-	unsafeslice(et, ptr, len)
-}
-
-func unsafeslicecheckptr(et *_type, ptr unsafe.Pointer, len64 int64) {
-	unsafeslice64(et, ptr, len64)
-
-	// Check that underlying array doesn't straddle multiple heap objects.
-	// unsafeslice64 has already checked for overflow.
-	if checkptrStraddles(ptr, uintptr(len64)*et.size) {
-		throw("checkptr: unsafe.Slice result straddles multiple allocations")
-	}
-}
-
-func panicunsafeslicelen() {
-	panic(errorString("unsafe.Slice: len out of range"))
-}
-
-// growslice handles slice growth during append.
-// It is passed the slice element type, the old slice, and the desired new minimum capacity,
-// and it returns a new slice with at least that capacity, with the old data
-// copied into it.
-// The new slice's length is set to the old slice's length,
-// NOT to the new requested capacity.
-// This is for codegen convenience. The old slice's length is used immediately
-// to calculate where to write new values during an append.
-// TODO: When the old backend is gone, reconsider this decision.
-// The SSA backend might prefer the new length or to return only ptr/cap and save stack space.
-func growslice(et *_type, old slice, cap int) slice {
-	if raceenabled {
-		callerpc := getcallerpc()
-		racereadrangepc(old.array, uintptr(old.len*int(et.size)), callerpc, abi.FuncPCABIInternal(growslice))
-	}
-	if msanenabled {
-		msanread(old.array, uintptr(old.len*int(et.size)))
-	}
-	if asanenabled {
-		asanread(old.array, uintptr(old.len*int(et.size)))
-	}
-
-	if cap < old.cap {
-		panic(errorString("growslice: cap out of range"))
-	}
-
-	if et.size == 0 {
-		// append should not create a slice with nil pointer but non-zero len.
-		// We assume that append doesn't need to preserve old.array in this case.
-		return slice{unsafe.Pointer(&zerobase), old.len, cap}
-	}
-
-	newcap := old.cap
-	doublecap := newcap + newcap
-	if cap > doublecap {
-		newcap = cap
-	} else {
-		const threshold = 256
-		if old.cap < threshold {
-			newcap = doublecap
-		} else {
-			// Check 0 < newcap to detect overflow
-			// and prevent an infinite loop.
-			for 0 < newcap && newcap < cap {
-				// Transition from growing 2x for small slices
-				// to growing 1.25x for large slices. This formula
-				// gives a smooth-ish transition between the two.
-				newcap += (newcap + 3*threshold) / 4
-			}
-			// Set newcap to the requested cap when
-			// the newcap calculation overflowed.
-			if newcap <= 0 {
-				newcap = cap
-			}
-		}
-	}
-
-	var overflow bool
-	var lenmem, newlenmem, capmem uintptr
-	// Specialize for common values of et.size.
-	// For 1 we don't need any division/multiplication.
-	// For goarch.PtrSize, compiler will optimize division/multiplication into a shift by a constant.
-	// For powers of 2, use a variable shift.
-	switch {
-	case et.size == 1:
-		lenmem = uintptr(old.len)
-		newlenmem = uintptr(cap)
-		capmem = roundupsize(uintptr(newcap))
-		overflow = uintptr(newcap) > maxAlloc
-		newcap = int(capmem)
-	case et.size == goarch.PtrSize:
-		lenmem = uintptr(old.len) * goarch.PtrSize
-		newlenmem = uintptr(cap) * goarch.PtrSize
-		capmem = roundupsize(uintptr(newcap) * goarch.PtrSize)
-		overflow = uintptr(newcap) > maxAlloc/goarch.PtrSize
-		newcap = int(capmem / goarch.PtrSize)
-	case isPowerOfTwo(et.size):
-		var shift uintptr
-		if goarch.PtrSize == 8 {
-			// Mask shift for better code generation.
-			shift = uintptr(sys.Ctz64(uint64(et.size))) & 63
-		} else {
-			shift = uintptr(sys.Ctz32(uint32(et.size))) & 31
-		}
-		lenmem = uintptr(old.len) << shift
-		newlenmem = uintptr(cap) << shift
-		capmem = roundupsize(uintptr(newcap) << shift)
-		overflow = uintptr(newcap) > (maxAlloc >> shift)
-		newcap = int(capmem >> shift)
-	default:
-		lenmem = uintptr(old.len) * et.size
-		newlenmem = uintptr(cap) * et.size
-		capmem, overflow = math.MulUintptr(et.size, uintptr(newcap))
-		capmem = roundupsize(capmem)
-		newcap = int(capmem / et.size)
-	}
-
-	// The check of overflow in addition to capmem > maxAlloc is needed
-	// to prevent an overflow which can be used to trigger a segfault
-	// on 32bit architectures with this example program:
-	//
-	// type T [1<<27 + 1]int64
-	//
-	// var d T
-	// var s []T
-	//
-	// func main() {
-	//   s = append(s, d, d, d, d)
-	//   print(len(s), "\n")
-	// }
-	if overflow || capmem > maxAlloc {
-		panic(errorString("growslice: cap out of range"))
-	}
-
-	var p unsafe.Pointer
-	if et.ptrdata == 0 {
-		p = mallocgc(capmem, nil, false)
-		// The append() that calls growslice is going to overwrite from old.len to cap (which will be the new length).
-		// Only clear the part that will not be overwritten.
-		memclrNoHeapPointers(add(p, newlenmem), capmem-newlenmem)
-	} else {
-		// Note: can't use rawmem (which avoids zeroing of memory), because then GC can scan uninitialized memory.
-		p = mallocgc(capmem, et, true)
-		if lenmem > 0 && writeBarrier.enabled {
-			// Only shade the pointers in old.array since we know the destination slice p
-			// only contains nil pointers because it has been cleared during alloc.
-			bulkBarrierPreWriteSrcOnly(uintptr(p), uintptr(old.array), lenmem-et.size+et.ptrdata)
-		}
-	}
-	memmove(p, old.array, lenmem)
-
-	return slice{p, old.len, newcap}
-}
-
-func isPowerOfTwo(x uintptr) bool {
-	return x&(x-1) == 0
-}
-
-// slicecopy is used to copy from a string or slice of pointerless elements into a slice.
-func slicecopy(toPtr unsafe.Pointer, toLen int, fromPtr unsafe.Pointer, fromLen int, width uintptr) int {
-	if fromLen == 0 || toLen == 0 {
-		return 0
-	}
-
-	n := fromLen
-	if toLen < n {
-		n = toLen
-	}
-
-	if width == 0 {
-		return n
-	}
-
-	size := uintptr(n) * width
-	if raceenabled {
-		callerpc := getcallerpc()
-		pc := abi.FuncPCABIInternal(slicecopy)
-		racereadrangepc(fromPtr, size, callerpc, pc)
-		racewriterangepc(toPtr, size, callerpc, pc)
-	}
-	if msanenabled {
-		msanread(fromPtr, size)
-		msanwrite(toPtr, size)
-	}
-	if asanenabled {
-		asanread(fromPtr, size)
-		asanwrite(toPtr, size)
-	}
-
-	if size == 1 { // common case worth about 2x to do here
-		// TODO: is this still worth it with new memmove impl?
-		*(*byte)(toPtr) = *(*byte)(fromPtr) // known to be a byte pointer
-	} else {
-		memmove(toPtr, fromPtr, size)
-	}
-	return n
-}
diff --git a/contrib/go/_std_1.18/src/runtime/stack.go b/contrib/go/_std_1.18/src/runtime/stack.go
deleted file mode 100644
index edc37d4878..0000000000
--- a/contrib/go/_std_1.18/src/runtime/stack.go
+++ /dev/null
@@ -1,1434 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"internal/abi"
-	"internal/cpu"
-	"internal/goarch"
-	"internal/goos"
-	"runtime/internal/atomic"
-	"runtime/internal/sys"
-	"unsafe"
-)
-
-/*
-Stack layout parameters.
-Included both by runtime (compiled via 6c) and linkers (compiled via gcc).
-
-The per-goroutine g->stackguard is set to point StackGuard bytes
-above the bottom of the stack.  Each function compares its stack
-pointer against g->stackguard to check for overflow.  To cut one
-instruction from the check sequence for functions with tiny frames,
-the stack is allowed to protrude StackSmall bytes below the stack
-guard.  Functions with large frames don't bother with the check and
-always call morestack.  The sequences are (for amd64, others are
-similar):
-
-	guard = g->stackguard
-	frame = function's stack frame size
-	argsize = size of function arguments (call + return)
-
-	stack frame size <= StackSmall:
-		CMPQ guard, SP
-		JHI 3(PC)
-		MOVQ m->morearg, $(argsize << 32)
-		CALL morestack(SB)
-
-	stack frame size > StackSmall but < StackBig
-		LEAQ (frame-StackSmall)(SP), R0
-		CMPQ guard, R0
-		JHI 3(PC)
-		MOVQ m->morearg, $(argsize << 32)
-		CALL morestack(SB)
-
-	stack frame size >= StackBig:
-		MOVQ m->morearg, $((argsize << 32) | frame)
-		CALL morestack(SB)
-
-The bottom StackGuard - StackSmall bytes are important: there has
-to be enough room to execute functions that refuse to check for
-stack overflow, either because they need to be adjacent to the
-actual caller's frame (deferproc) or because they handle the imminent
-stack overflow (morestack).
-
-For example, deferproc might call malloc, which does one of the
-above checks (without allocating a full frame), which might trigger
-a call to morestack.  This sequence needs to fit in the bottom
-section of the stack.  On amd64, morestack's frame is 40 bytes, and
-deferproc's frame is 56 bytes.  That fits well within the
-StackGuard - StackSmall bytes at the bottom.
-The linkers explore all possible call traces involving non-splitting
-functions to make sure that this limit cannot be violated.
-*/
-
-const (
-	// StackSystem is a number of additional bytes to add
-	// to each stack below the usual guard area for OS-specific
-	// purposes like signal handling. Used on Windows, Plan 9,
-	// and iOS because they do not use a separate stack.
-	_StackSystem = goos.IsWindows*512*goarch.PtrSize + goos.IsPlan9*512 + goos.IsIos*goarch.IsArm64*1024
-
-	// The minimum size of stack used by Go code
-	_StackMin = 2048
-
-	// The minimum stack size to allocate.
-	// The hackery here rounds FixedStack0 up to a power of 2.
-	_FixedStack0 = _StackMin + _StackSystem
-	_FixedStack1 = _FixedStack0 - 1
-	_FixedStack2 = _FixedStack1 | (_FixedStack1 >> 1)
-	_FixedStack3 = _FixedStack2 | (_FixedStack2 >> 2)
-	_FixedStack4 = _FixedStack3 | (_FixedStack3 >> 4)
-	_FixedStack5 = _FixedStack4 | (_FixedStack4 >> 8)
-	_FixedStack6 = _FixedStack5 | (_FixedStack5 >> 16)
-	_FixedStack  = _FixedStack6 + 1
-
-	// Functions that need frames bigger than this use an extra
-	// instruction to do the stack split check, to avoid overflow
-	// in case SP - framesize wraps below zero.
-	// This value can be no bigger than the size of the unmapped
-	// space at zero.
-	_StackBig = 4096
-
-	// The stack guard is a pointer this many bytes above the
-	// bottom of the stack.
-	//
-	// The guard leaves enough room for one _StackSmall frame plus
-	// a _StackLimit chain of NOSPLIT calls plus _StackSystem
-	// bytes for the OS.
-	_StackGuard = 928*sys.StackGuardMultiplier + _StackSystem
-
-	// After a stack split check the SP is allowed to be this
-	// many bytes below the stack guard. This saves an instruction
-	// in the checking sequence for tiny frames.
-	_StackSmall = 128
-
-	// The maximum number of bytes that a chain of NOSPLIT
-	// functions can use.
-	_StackLimit = _StackGuard - _StackSystem - _StackSmall
-)
-
-const (
-	// stackDebug == 0: no logging
-	//            == 1: logging of per-stack operations
-	//            == 2: logging of per-frame operations
-	//            == 3: logging of per-word updates
-	//            == 4: logging of per-word reads
-	stackDebug       = 0
-	stackFromSystem  = 0 // allocate stacks from system memory instead of the heap
-	stackFaultOnFree = 0 // old stacks are mapped noaccess to detect use after free
-	stackPoisonCopy  = 0 // fill stack that should not be accessed with garbage, to detect bad dereferences during copy
-	stackNoCache     = 0 // disable per-P small stack caches
-
-	// check the BP links during traceback.
-	debugCheckBP = false
-)
-
-const (
-	uintptrMask = 1<<(8*goarch.PtrSize) - 1
-
-	// The values below can be stored to g.stackguard0 to force
-	// the next stack check to fail.
-	// These are all larger than any real SP.
-
-	// Goroutine preemption request.
-	// 0xfffffade in hex.
-	stackPreempt = uintptrMask & -1314
-
-	// Thread is forking. Causes a split stack check failure.
-	// 0xfffffb2e in hex.
-	stackFork = uintptrMask & -1234
-
-	// Force a stack movement. Used for debugging.
-	// 0xfffffeed in hex.
-	stackForceMove = uintptrMask & -275
-
-	// stackPoisonMin is the lowest allowed stack poison value.
-	stackPoisonMin = uintptrMask & -4096
-)
-
-// Global pool of spans that have free stacks.
-// Stacks are assigned an order according to size.
-//     order = log_2(size/FixedStack)
-// There is a free list for each order.
-var stackpool [_NumStackOrders]struct {
-	item stackpoolItem
-	_    [cpu.CacheLinePadSize - unsafe.Sizeof(stackpoolItem{})%cpu.CacheLinePadSize]byte
-}
-
-//go:notinheap
-type stackpoolItem struct {
-	mu   mutex
-	span mSpanList
-}
-
-// Global pool of large stack spans.
-var stackLarge struct {
-	lock mutex
-	free [heapAddrBits - pageShift]mSpanList // free lists by log_2(s.npages)
-}
-
-func stackinit() {
-	if _StackCacheSize&_PageMask != 0 {
-		throw("cache size must be a multiple of page size")
-	}
-	for i := range stackpool {
-		stackpool[i].item.span.init()
-		lockInit(&stackpool[i].item.mu, lockRankStackpool)
-	}
-	for i := range stackLarge.free {
-		stackLarge.free[i].init()
-		lockInit(&stackLarge.lock, lockRankStackLarge)
-	}
-}
-
-// stacklog2 returns ⌊log_2(n)⌋.
-func stacklog2(n uintptr) int {
-	log2 := 0
-	for n > 1 {
-		n >>= 1
-		log2++
-	}
-	return log2
-}
-
-// Allocates a stack from the free pool. Must be called with
-// stackpool[order].item.mu held.
-func stackpoolalloc(order uint8) gclinkptr {
-	list := &stackpool[order].item.span
-	s := list.first
-	lockWithRankMayAcquire(&mheap_.lock, lockRankMheap)
-	if s == nil {
-		// no free stacks. Allocate another span worth.
-		s = mheap_.allocManual(_StackCacheSize>>_PageShift, spanAllocStack)
-		if s == nil {
-			throw("out of memory")
-		}
-		if s.allocCount != 0 {
-			throw("bad allocCount")
-		}
-		if s.manualFreeList.ptr() != nil {
-			throw("bad manualFreeList")
-		}
-		osStackAlloc(s)
-		s.elemsize = _FixedStack << order
-		for i := uintptr(0); i < _StackCacheSize; i += s.elemsize {
-			x := gclinkptr(s.base() + i)
-			x.ptr().next = s.manualFreeList
-			s.manualFreeList = x
-		}
-		list.insert(s)
-	}
-	x := s.manualFreeList
-	if x.ptr() == nil {
-		throw("span has no free stacks")
-	}
-	s.manualFreeList = x.ptr().next
-	s.allocCount++
-	if s.manualFreeList.ptr() == nil {
-		// all stacks in s are allocated.
-		list.remove(s)
-	}
-	return x
-}
-
-// Adds stack x to the free pool. Must be called with stackpool[order].item.mu held.
-func stackpoolfree(x gclinkptr, order uint8) {
-	s := spanOfUnchecked(uintptr(x))
-	if s.state.get() != mSpanManual {
-		throw("freeing stack not in a stack span")
-	}
-	if s.manualFreeList.ptr() == nil {
-		// s will now have a free stack
-		stackpool[order].item.span.insert(s)
-	}
-	x.ptr().next = s.manualFreeList
-	s.manualFreeList = x
-	s.allocCount--
-	if gcphase == _GCoff && s.allocCount == 0 {
-		// Span is completely free. Return it to the heap
-		// immediately if we're sweeping.
-		//
-		// If GC is active, we delay the free until the end of
-		// GC to avoid the following type of situation:
-		//
-		// 1) GC starts, scans a SudoG but does not yet mark the SudoG.elem pointer
-		// 2) The stack that pointer points to is copied
-		// 3) The old stack is freed
-		// 4) The containing span is marked free
-		// 5) GC attempts to mark the SudoG.elem pointer. The
-		//    marking fails because the pointer looks like a
-		//    pointer into a free span.
-		//
-		// By not freeing, we prevent step #4 until GC is done.
-		stackpool[order].item.span.remove(s)
-		s.manualFreeList = 0
-		osStackFree(s)
-		mheap_.freeManual(s, spanAllocStack)
-	}
-}
-
-// stackcacherefill/stackcacherelease implement a global pool of stack segments.
-// The pool is required to prevent unlimited growth of per-thread caches.
-//
-//go:systemstack
-func stackcacherefill(c *mcache, order uint8) {
-	if stackDebug >= 1 {
-		print("stackcacherefill order=", order, "\n")
-	}
-
-	// Grab some stacks from the global cache.
-	// Grab half of the allowed capacity (to prevent thrashing).
-	var list gclinkptr
-	var size uintptr
-	lock(&stackpool[order].item.mu)
-	for size < _StackCacheSize/2 {
-		x := stackpoolalloc(order)
-		x.ptr().next = list
-		list = x
-		size += _FixedStack << order
-	}
-	unlock(&stackpool[order].item.mu)
-	c.stackcache[order].list = list
-	c.stackcache[order].size = size
-}
-
-//go:systemstack
-func stackcacherelease(c *mcache, order uint8) {
-	if stackDebug >= 1 {
-		print("stackcacherelease order=", order, "\n")
-	}
-	x := c.stackcache[order].list
-	size := c.stackcache[order].size
-	lock(&stackpool[order].item.mu)
-	for size > _StackCacheSize/2 {
-		y := x.ptr().next
-		stackpoolfree(x, order)
-		x = y
-		size -= _FixedStack << order
-	}
-	unlock(&stackpool[order].item.mu)
-	c.stackcache[order].list = x
-	c.stackcache[order].size = size
-}
-
-//go:systemstack
-func stackcache_clear(c *mcache) {
-	if stackDebug >= 1 {
-		print("stackcache clear\n")
-	}
-	for order := uint8(0); order < _NumStackOrders; order++ {
-		lock(&stackpool[order].item.mu)
-		x := c.stackcache[order].list
-		for x.ptr() != nil {
-			y := x.ptr().next
-			stackpoolfree(x, order)
-			x = y
-		}
-		c.stackcache[order].list = 0
-		c.stackcache[order].size = 0
-		unlock(&stackpool[order].item.mu)
-	}
-}
-
-// stackalloc allocates an n byte stack.
-//
-// stackalloc must run on the system stack because it uses per-P
-// resources and must not split the stack.
-//
-//go:systemstack
-func stackalloc(n uint32) stack {
-	// Stackalloc must be called on scheduler stack, so that we
-	// never try to grow the stack during the code that stackalloc runs.
-	// Doing so would cause a deadlock (issue 1547).
-	thisg := getg()
-	if thisg != thisg.m.g0 {
-		throw("stackalloc not on scheduler stack")
-	}
-	if n&(n-1) != 0 {
-		throw("stack size not a power of 2")
-	}
-	if stackDebug >= 1 {
-		print("stackalloc ", n, "\n")
-	}
-
-	if debug.efence != 0 || stackFromSystem != 0 {
-		n = uint32(alignUp(uintptr(n), physPageSize))
-		v := sysAlloc(uintptr(n), &memstats.stacks_sys)
-		if v == nil {
-			throw("out of memory (stackalloc)")
-		}
-		return stack{uintptr(v), uintptr(v) + uintptr(n)}
-	}
-
-	// Small stacks are allocated with a fixed-size free-list allocator.
-	// If we need a stack of a bigger size, we fall back on allocating
-	// a dedicated span.
-	var v unsafe.Pointer
-	if n < _FixedStack<<_NumStackOrders && n < _StackCacheSize {
-		order := uint8(0)
-		n2 := n
-		for n2 > _FixedStack {
-			order++
-			n2 >>= 1
-		}
-		var x gclinkptr
-		if stackNoCache != 0 || thisg.m.p == 0 || thisg.m.preemptoff != "" {
-			// thisg.m.p == 0 can happen in the guts of exitsyscall
-			// or procresize. Just get a stack from the global pool.
-			// Also don't touch stackcache during gc
-			// as it's flushed concurrently.
-			lock(&stackpool[order].item.mu)
-			x = stackpoolalloc(order)
-			unlock(&stackpool[order].item.mu)
-		} else {
-			c := thisg.m.p.ptr().mcache
-			x = c.stackcache[order].list
-			if x.ptr() == nil {
-				stackcacherefill(c, order)
-				x = c.stackcache[order].list
-			}
-			c.stackcache[order].list = x.ptr().next
-			c.stackcache[order].size -= uintptr(n)
-		}
-		v = unsafe.Pointer(x)
-	} else {
-		var s *mspan
-		npage := uintptr(n) >> _PageShift
-		log2npage := stacklog2(npage)
-
-		// Try to get a stack from the large stack cache.
-		lock(&stackLarge.lock)
-		if !stackLarge.free[log2npage].isEmpty() {
-			s = stackLarge.free[log2npage].first
-			stackLarge.free[log2npage].remove(s)
-		}
-		unlock(&stackLarge.lock)
-
-		lockWithRankMayAcquire(&mheap_.lock, lockRankMheap)
-
-		if s == nil {
-			// Allocate a new stack from the heap.
-			s = mheap_.allocManual(npage, spanAllocStack)
-			if s == nil {
-				throw("out of memory")
-			}
-			osStackAlloc(s)
-			s.elemsize = uintptr(n)
-		}
-		v = unsafe.Pointer(s.base())
-	}
-
-	if raceenabled {
-		racemalloc(v, uintptr(n))
-	}
-	if msanenabled {
-		msanmalloc(v, uintptr(n))
-	}
-	if asanenabled {
-		asanunpoison(v, uintptr(n))
-	}
-	if stackDebug >= 1 {
-		print("  allocated ", v, "\n")
-	}
-	return stack{uintptr(v), uintptr(v) + uintptr(n)}
-}
-
-// stackfree frees an n byte stack allocation at stk.
-//
-// stackfree must run on the system stack because it uses per-P
-// resources and must not split the stack.
-//
-//go:systemstack
-func stackfree(stk stack) {
-	gp := getg()
-	v := unsafe.Pointer(stk.lo)
-	n := stk.hi - stk.lo
-	if n&(n-1) != 0 {
-		throw("stack not a power of 2")
-	}
-	if stk.lo+n < stk.hi {
-		throw("bad stack size")
-	}
-	if stackDebug >= 1 {
-		println("stackfree", v, n)
-		memclrNoHeapPointers(v, n) // for testing, clobber stack data
-	}
-	if debug.efence != 0 || stackFromSystem != 0 {
-		if debug.efence != 0 || stackFaultOnFree != 0 {
-			sysFault(v, n)
-		} else {
-			sysFree(v, n, &memstats.stacks_sys)
-		}
-		return
-	}
-	if msanenabled {
-		msanfree(v, n)
-	}
-	if asanenabled {
-		asanpoison(v, n)
-	}
-	if n < _FixedStack<<_NumStackOrders && n < _StackCacheSize {
-		order := uint8(0)
-		n2 := n
-		for n2 > _FixedStack {
-			order++
-			n2 >>= 1
-		}
-		x := gclinkptr(v)
-		if stackNoCache != 0 || gp.m.p == 0 || gp.m.preemptoff != "" {
-			lock(&stackpool[order].item.mu)
-			stackpoolfree(x, order)
-			unlock(&stackpool[order].item.mu)
-		} else {
-			c := gp.m.p.ptr().mcache
-			if c.stackcache[order].size >= _StackCacheSize {
-				stackcacherelease(c, order)
-			}
-			x.ptr().next = c.stackcache[order].list
-			c.stackcache[order].list = x
-			c.stackcache[order].size += n
-		}
-	} else {
-		s := spanOfUnchecked(uintptr(v))
-		if s.state.get() != mSpanManual {
-			println(hex(s.base()), v)
-			throw("bad span state")
-		}
-		if gcphase == _GCoff {
-			// Free the stack immediately if we're
-			// sweeping.
-			osStackFree(s)
-			mheap_.freeManual(s, spanAllocStack)
-		} else {
-			// If the GC is running, we can't return a
-			// stack span to the heap because it could be
-			// reused as a heap span, and this state
-			// change would race with GC. Add it to the
-			// large stack cache instead.
-			log2npage := stacklog2(s.npages)
-			lock(&stackLarge.lock)
-			stackLarge.free[log2npage].insert(s)
-			unlock(&stackLarge.lock)
-		}
-	}
-}
-
-var maxstacksize uintptr = 1 << 20 // enough until runtime.main sets it for real
-
-var maxstackceiling = maxstacksize
-
-var ptrnames = []string{
-	0: "scalar",
-	1: "ptr",
-}
-
-// Stack frame layout
-//
-// (x86)
-// +------------------+
-// | args from caller |
-// +------------------+ <- frame->argp
-// |  return address  |
-// +------------------+
-// |  caller's BP (*) | (*) if framepointer_enabled && varp < sp
-// +------------------+ <- frame->varp
-// |     locals       |
-// +------------------+
-// |  args to callee  |
-// +------------------+ <- frame->sp
-//
-// (arm)
-// +------------------+
-// | args from caller |
-// +------------------+ <- frame->argp
-// | caller's retaddr |
-// +------------------+ <- frame->varp
-// |     locals       |
-// +------------------+
-// |  args to callee  |
-// +------------------+
-// |  return address  |
-// +------------------+ <- frame->sp
-
-type adjustinfo struct {
-	old   stack
-	delta uintptr // ptr distance from old to new stack (newbase - oldbase)
-	cache pcvalueCache
-
-	// sghi is the highest sudog.elem on the stack.
-	sghi uintptr
-}
-
-// Adjustpointer checks whether *vpp is in the old stack described by adjinfo.
-// If so, it rewrites *vpp to point into the new stack.
-func adjustpointer(adjinfo *adjustinfo, vpp unsafe.Pointer) {
-	pp := (*uintptr)(vpp)
-	p := *pp
-	if stackDebug >= 4 {
-		print("        ", pp, ":", hex(p), "\n")
-	}
-	if adjinfo.old.lo <= p && p < adjinfo.old.hi {
-		*pp = p + adjinfo.delta
-		if stackDebug >= 3 {
-			print("        adjust ptr ", pp, ":", hex(p), " -> ", hex(*pp), "\n")
-		}
-	}
-}
-
-// Information from the compiler about the layout of stack frames.
-// Note: this type must agree with reflect.bitVector.
-type bitvector struct {
-	n        int32 // # of bits
-	bytedata *uint8
-}
-
-// ptrbit returns the i'th bit in bv.
-// ptrbit is less efficient than iterating directly over bitvector bits,
-// and should only be used in non-performance-critical code.
-// See adjustpointers for an example of a high-efficiency walk of a bitvector.
-func (bv *bitvector) ptrbit(i uintptr) uint8 {
-	b := *(addb(bv.bytedata, i/8))
-	return (b >> (i % 8)) & 1
-}
-
-// bv describes the memory starting at address scanp.
-// Adjust any pointers contained therein.
-func adjustpointers(scanp unsafe.Pointer, bv *bitvector, adjinfo *adjustinfo, f funcInfo) {
-	minp := adjinfo.old.lo
-	maxp := adjinfo.old.hi
-	delta := adjinfo.delta
-	num := uintptr(bv.n)
-	// If this frame might contain channel receive slots, use CAS
-	// to adjust pointers. If the slot hasn't been received into
-	// yet, it may contain stack pointers and a concurrent send
-	// could race with adjusting those pointers. (The sent value
-	// itself can never contain stack pointers.)
-	useCAS := uintptr(scanp) < adjinfo.sghi
-	for i := uintptr(0); i < num; i += 8 {
-		if stackDebug >= 4 {
-			for j := uintptr(0); j < 8; j++ {
-				print("        ", add(scanp, (i+j)*goarch.PtrSize), ":", ptrnames[bv.ptrbit(i+j)], ":", hex(*(*uintptr)(add(scanp, (i+j)*goarch.PtrSize))), " # ", i, " ", *addb(bv.bytedata, i/8), "\n")
-			}
-		}
-		b := *(addb(bv.bytedata, i/8))
-		for b != 0 {
-			j := uintptr(sys.Ctz8(b))
-			b &= b - 1
-			pp := (*uintptr)(add(scanp, (i+j)*goarch.PtrSize))
-		retry:
-			p := *pp
-			if f.valid() && 0 < p && p < minLegalPointer && debug.invalidptr != 0 {
-				// Looks like a junk value in a pointer slot.
-				// Live analysis wrong?
-				getg().m.traceback = 2
-				print("runtime: bad pointer in frame ", funcname(f), " at ", pp, ": ", hex(p), "\n")
-				throw("invalid pointer found on stack")
-			}
-			if minp <= p && p < maxp {
-				if stackDebug >= 3 {
-					print("adjust ptr ", hex(p), " ", funcname(f), "\n")
-				}
-				if useCAS {
-					ppu := (*unsafe.Pointer)(unsafe.Pointer(pp))
-					if !atomic.Casp1(ppu, unsafe.Pointer(p), unsafe.Pointer(p+delta)) {
-						goto retry
-					}
-				} else {
-					*pp = p + delta
-				}
-			}
-		}
-	}
-}
-
-// Note: the argument/return area is adjusted by the callee.
-func adjustframe(frame *stkframe, arg unsafe.Pointer) bool {
-	adjinfo := (*adjustinfo)(arg)
-	if frame.continpc == 0 {
-		// Frame is dead.
-		return true
-	}
-	f := frame.fn
-	if stackDebug >= 2 {
-		print("    adjusting ", funcname(f), " frame=[", hex(frame.sp), ",", hex(frame.fp), "] pc=", hex(frame.pc), " continpc=", hex(frame.continpc), "\n")
-	}
-	if f.funcID == funcID_systemstack_switch {
-		// A special routine at the bottom of stack of a goroutine that does a systemstack call.
-		// We will allow it to be copied even though we don't
-		// have full GC info for it (because it is written in asm).
-		return true
-	}
-
-	locals, args, objs := getStackMap(frame, &adjinfo.cache, true)
-
-	// Adjust local variables if stack frame has been allocated.
-	if locals.n > 0 {
-		size := uintptr(locals.n) * goarch.PtrSize
-		adjustpointers(unsafe.Pointer(frame.varp-size), &locals, adjinfo, f)
-	}
-
-	// Adjust saved base pointer if there is one.
-	// TODO what about arm64 frame pointer adjustment?
-	if goarch.ArchFamily == goarch.AMD64 && frame.argp-frame.varp == 2*goarch.PtrSize {
-		if stackDebug >= 3 {
-			print("      saved bp\n")
-		}
-		if debugCheckBP {
-			// Frame pointers should always point to the next higher frame on
-			// the Go stack (or be nil, for the top frame on the stack).
-			bp := *(*uintptr)(unsafe.Pointer(frame.varp))
-			if bp != 0 && (bp < adjinfo.old.lo || bp >= adjinfo.old.hi) {
-				println("runtime: found invalid frame pointer")
-				print("bp=", hex(bp), " min=", hex(adjinfo.old.lo), " max=", hex(adjinfo.old.hi), "\n")
-				throw("bad frame pointer")
-			}
-		}
-		adjustpointer(adjinfo, unsafe.Pointer(frame.varp))
-	}
-
-	// Adjust arguments.
-	if args.n > 0 {
-		if stackDebug >= 3 {
-			print("      args\n")
-		}
-		adjustpointers(unsafe.Pointer(frame.argp), &args, adjinfo, funcInfo{})
-	}
-
-	// Adjust pointers in all stack objects (whether they are live or not).
-	// See comments in mgcmark.go:scanframeworker.
-	if frame.varp != 0 {
-		for i := range objs {
-			obj := &objs[i]
-			off := obj.off
-			base := frame.varp // locals base pointer
-			if off >= 0 {
-				base = frame.argp // arguments and return values base pointer
-			}
-			p := base + uintptr(off)
-			if p < frame.sp {
-				// Object hasn't been allocated in the frame yet.
-				// (Happens when the stack bounds check fails and
-				// we call into morestack.)
-				continue
-			}
-			ptrdata := obj.ptrdata()
-			gcdata := obj.gcdata()
-			var s *mspan
-			if obj.useGCProg() {
-				// See comments in mgcmark.go:scanstack
-				s = materializeGCProg(ptrdata, gcdata)
-				gcdata = (*byte)(unsafe.Pointer(s.startAddr))
-			}
-			for i := uintptr(0); i < ptrdata; i += goarch.PtrSize {
-				if *addb(gcdata, i/(8*goarch.PtrSize))>>(i/goarch.PtrSize&7)&1 != 0 {
-					adjustpointer(adjinfo, unsafe.Pointer(p+i))
-				}
-			}
-			if s != nil {
-				dematerializeGCProg(s)
-			}
-		}
-	}
-
-	return true
-}
-
-func adjustctxt(gp *g, adjinfo *adjustinfo) {
-	adjustpointer(adjinfo, unsafe.Pointer(&gp.sched.ctxt))
-	if !framepointer_enabled {
-		return
-	}
-	if debugCheckBP {
-		bp := gp.sched.bp
-		if bp != 0 && (bp < adjinfo.old.lo || bp >= adjinfo.old.hi) {
-			println("runtime: found invalid top frame pointer")
-			print("bp=", hex(bp), " min=", hex(adjinfo.old.lo), " max=", hex(adjinfo.old.hi), "\n")
-			throw("bad top frame pointer")
-		}
-	}
-	adjustpointer(adjinfo, unsafe.Pointer(&gp.sched.bp))
-}
-
-func adjustdefers(gp *g, adjinfo *adjustinfo) {
-	// Adjust pointers in the Defer structs.
-	// We need to do this first because we need to adjust the
-	// defer.link fields so we always work on the new stack.
-	adjustpointer(adjinfo, unsafe.Pointer(&gp._defer))
-	for d := gp._defer; d != nil; d = d.link {
-		adjustpointer(adjinfo, unsafe.Pointer(&d.fn))
-		adjustpointer(adjinfo, unsafe.Pointer(&d.sp))
-		adjustpointer(adjinfo, unsafe.Pointer(&d._panic))
-		adjustpointer(adjinfo, unsafe.Pointer(&d.link))
-		adjustpointer(adjinfo, unsafe.Pointer(&d.varp))
-		adjustpointer(adjinfo, unsafe.Pointer(&d.fd))
-	}
-}
-
-func adjustpanics(gp *g, adjinfo *adjustinfo) {
-	// Panics are on stack and already adjusted.
-	// Update pointer to head of list in G.
-	adjustpointer(adjinfo, unsafe.Pointer(&gp._panic))
-}
-
-func adjustsudogs(gp *g, adjinfo *adjustinfo) {
-	// the data elements pointed to by a SudoG structure
-	// might be in the stack.
-	for s := gp.waiting; s != nil; s = s.waitlink {
-		adjustpointer(adjinfo, unsafe.Pointer(&s.elem))
-	}
-}
-
-func fillstack(stk stack, b byte) {
-	for p := stk.lo; p < stk.hi; p++ {
-		*(*byte)(unsafe.Pointer(p)) = b
-	}
-}
-
-func findsghi(gp *g, stk stack) uintptr {
-	var sghi uintptr
-	for sg := gp.waiting; sg != nil; sg = sg.waitlink {
-		p := uintptr(sg.elem) + uintptr(sg.c.elemsize)
-		if stk.lo <= p && p < stk.hi && p > sghi {
-			sghi = p
-		}
-	}
-	return sghi
-}
-
-// syncadjustsudogs adjusts gp's sudogs and copies the part of gp's
-// stack they refer to while synchronizing with concurrent channel
-// operations. It returns the number of bytes of stack copied.
-func syncadjustsudogs(gp *g, used uintptr, adjinfo *adjustinfo) uintptr {
-	if gp.waiting == nil {
-		return 0
-	}
-
-	// Lock channels to prevent concurrent send/receive.
-	var lastc *hchan
-	for sg := gp.waiting; sg != nil; sg = sg.waitlink {
-		if sg.c != lastc {
-			// There is a ranking cycle here between gscan bit and
-			// hchan locks. Normally, we only allow acquiring hchan
-			// locks and then getting a gscan bit. In this case, we
-			// already have the gscan bit. We allow acquiring hchan
-			// locks here as a special case, since a deadlock can't
-			// happen because the G involved must already be
-			// suspended. So, we get a special hchan lock rank here
-			// that is lower than gscan, but doesn't allow acquiring
-			// any other locks other than hchan.
-			lockWithRank(&sg.c.lock, lockRankHchanLeaf)
-		}
-		lastc = sg.c
-	}
-
-	// Adjust sudogs.
-	adjustsudogs(gp, adjinfo)
-
-	// Copy the part of the stack the sudogs point in to
-	// while holding the lock to prevent races on
-	// send/receive slots.
-	var sgsize uintptr
-	if adjinfo.sghi != 0 {
-		oldBot := adjinfo.old.hi - used
-		newBot := oldBot + adjinfo.delta
-		sgsize = adjinfo.sghi - oldBot
-		memmove(unsafe.Pointer(newBot), unsafe.Pointer(oldBot), sgsize)
-	}
-
-	// Unlock channels.
-	lastc = nil
-	for sg := gp.waiting; sg != nil; sg = sg.waitlink {
-		if sg.c != lastc {
-			unlock(&sg.c.lock)
-		}
-		lastc = sg.c
-	}
-
-	return sgsize
-}
-
-// Copies gp's stack to a new stack of a different size.
-// Caller must have changed gp status to Gcopystack.
-func copystack(gp *g, newsize uintptr) {
-	if gp.syscallsp != 0 {
-		throw("stack growth not allowed in system call")
-	}
-	old := gp.stack
-	if old.lo == 0 {
-		throw("nil stackbase")
-	}
-	used := old.hi - gp.sched.sp
-	// Add just the difference to gcController.addScannableStack.
-	// g0 stacks never move, so this will never account for them.
-	// It's also fine if we have no P, addScannableStack can deal with
-	// that case.
-	gcController.addScannableStack(getg().m.p.ptr(), int64(newsize)-int64(old.hi-old.lo))
-
-	// allocate new stack
-	new := stackalloc(uint32(newsize))
-	if stackPoisonCopy != 0 {
-		fillstack(new, 0xfd)
-	}
-	if stackDebug >= 1 {
-		print("copystack gp=", gp, " [", hex(old.lo), " ", hex(old.hi-used), " ", hex(old.hi), "]", " -> [", hex(new.lo), " ", hex(new.hi-used), " ", hex(new.hi), "]/", newsize, "\n")
-	}
-
-	// Compute adjustment.
-	var adjinfo adjustinfo
-	adjinfo.old = old
-	adjinfo.delta = new.hi - old.hi
-
-	// Adjust sudogs, synchronizing with channel ops if necessary.
-	ncopy := used
-	if !gp.activeStackChans {
-		if newsize < old.hi-old.lo && atomic.Load8(&gp.parkingOnChan) != 0 {
-			// It's not safe for someone to shrink this stack while we're actively
-			// parking on a channel, but it is safe to grow since we do that
-			// ourselves and explicitly don't want to synchronize with channels
-			// since we could self-deadlock.
-			throw("racy sudog adjustment due to parking on channel")
-		}
-		adjustsudogs(gp, &adjinfo)
-	} else {
-		// sudogs may be pointing in to the stack and gp has
-		// released channel locks, so other goroutines could
-		// be writing to gp's stack. Find the highest such
-		// pointer so we can handle everything there and below
-		// carefully. (This shouldn't be far from the bottom
-		// of the stack, so there's little cost in handling
-		// everything below it carefully.)
-		adjinfo.sghi = findsghi(gp, old)
-
-		// Synchronize with channel ops and copy the part of
-		// the stack they may interact with.
-		ncopy -= syncadjustsudogs(gp, used, &adjinfo)
-	}
-
-	// Copy the stack (or the rest of it) to the new location
-	memmove(unsafe.Pointer(new.hi-ncopy), unsafe.Pointer(old.hi-ncopy), ncopy)
-
-	// Adjust remaining structures that have pointers into stacks.
-	// We have to do most of these before we traceback the new
-	// stack because gentraceback uses them.
-	adjustctxt(gp, &adjinfo)
-	adjustdefers(gp, &adjinfo)
-	adjustpanics(gp, &adjinfo)
-	if adjinfo.sghi != 0 {
-		adjinfo.sghi += adjinfo.delta
-	}
-
-	// Swap out old stack for new one
-	gp.stack = new
-	gp.stackguard0 = new.lo + _StackGuard // NOTE: might clobber a preempt request
-	gp.sched.sp = new.hi - used
-	gp.stktopsp += adjinfo.delta
-
-	// Adjust pointers in the new stack.
-	gentraceback(^uintptr(0), ^uintptr(0), 0, gp, 0, nil, 0x7fffffff, adjustframe, noescape(unsafe.Pointer(&adjinfo)), 0)
-
-	// free old stack
-	if stackPoisonCopy != 0 {
-		fillstack(old, 0xfc)
-	}
-	stackfree(old)
-}
-
-// round x up to a power of 2.
-func round2(x int32) int32 {
-	s := uint(0)
-	for 1<<s < x {
-		s++
-	}
-	return 1 << s
-}
-
-// Called from runtime·morestack when more stack is needed.
-// Allocate larger stack and relocate to new stack.
-// Stack growth is multiplicative, for constant amortized cost.
-//
-// g->atomicstatus will be Grunning or Gscanrunning upon entry.
-// If the scheduler is trying to stop this g, then it will set preemptStop.
-//
-// This must be nowritebarrierrec because it can be called as part of
-// stack growth from other nowritebarrierrec functions, but the
-// compiler doesn't check this.
-//
-//go:nowritebarrierrec
-func newstack() {
-	thisg := getg()
-	// TODO: double check all gp. shouldn't be getg().
-	if thisg.m.morebuf.g.ptr().stackguard0 == stackFork {
-		throw("stack growth after fork")
-	}
-	if thisg.m.morebuf.g.ptr() != thisg.m.curg {
-		print("runtime: newstack called from g=", hex(thisg.m.morebuf.g), "\n"+"\tm=", thisg.m, " m->curg=", thisg.m.curg, " m->g0=", thisg.m.g0, " m->gsignal=", thisg.m.gsignal, "\n")
-		morebuf := thisg.m.morebuf
-		traceback(morebuf.pc, morebuf.sp, morebuf.lr, morebuf.g.ptr())
-		throw("runtime: wrong goroutine in newstack")
-	}
-
-	gp := thisg.m.curg
-
-	if thisg.m.curg.throwsplit {
-		// Update syscallsp, syscallpc in case traceback uses them.
-		morebuf := thisg.m.morebuf
-		gp.syscallsp = morebuf.sp
-		gp.syscallpc = morebuf.pc
-		pcname, pcoff := "(unknown)", uintptr(0)
-		f := findfunc(gp.sched.pc)
-		if f.valid() {
-			pcname = funcname(f)
-			pcoff = gp.sched.pc - f.entry()
-		}
-		print("runtime: newstack at ", pcname, "+", hex(pcoff),
-			" sp=", hex(gp.sched.sp), " stack=[", hex(gp.stack.lo), ", ", hex(gp.stack.hi), "]\n",
-			"\tmorebuf={pc:", hex(morebuf.pc), " sp:", hex(morebuf.sp), " lr:", hex(morebuf.lr), "}\n",
-			"\tsched={pc:", hex(gp.sched.pc), " sp:", hex(gp.sched.sp), " lr:", hex(gp.sched.lr), " ctxt:", gp.sched.ctxt, "}\n")
-
-		thisg.m.traceback = 2 // Include runtime frames
-		traceback(morebuf.pc, morebuf.sp, morebuf.lr, gp)
-		throw("runtime: stack split at bad time")
-	}
-
-	morebuf := thisg.m.morebuf
-	thisg.m.morebuf.pc = 0
-	thisg.m.morebuf.lr = 0
-	thisg.m.morebuf.sp = 0
-	thisg.m.morebuf.g = 0
-
-	// NOTE: stackguard0 may change underfoot, if another thread
-	// is about to try to preempt gp. Read it just once and use that same
-	// value now and below.
-	stackguard0 := atomic.Loaduintptr(&gp.stackguard0)
-
-	// Be conservative about where we preempt.
-	// We are interested in preempting user Go code, not runtime code.
-	// If we're holding locks, mallocing, or preemption is disabled, don't
-	// preempt.
-	// This check is very early in newstack so that even the status change
-	// from Grunning to Gwaiting and back doesn't happen in this case.
-	// That status change by itself can be viewed as a small preemption,
-	// because the GC might change Gwaiting to Gscanwaiting, and then
-	// this goroutine has to wait for the GC to finish before continuing.
-	// If the GC is in some way dependent on this goroutine (for example,
-	// it needs a lock held by the goroutine), that small preemption turns
-	// into a real deadlock.
-	preempt := stackguard0 == stackPreempt
-	if preempt {
-		if !canPreemptM(thisg.m) {
-			// Let the goroutine keep running for now.
-			// gp->preempt is set, so it will be preempted next time.
-			gp.stackguard0 = gp.stack.lo + _StackGuard
-			gogo(&gp.sched) // never return
-		}
-	}
-
-	if gp.stack.lo == 0 {
-		throw("missing stack in newstack")
-	}
-	sp := gp.sched.sp
-	if goarch.ArchFamily == goarch.AMD64 || goarch.ArchFamily == goarch.I386 || goarch.ArchFamily == goarch.WASM {
-		// The call to morestack cost a word.
-		sp -= goarch.PtrSize
-	}
-	if stackDebug >= 1 || sp < gp.stack.lo {
-		print("runtime: newstack sp=", hex(sp), " stack=[", hex(gp.stack.lo), ", ", hex(gp.stack.hi), "]\n",
-			"\tmorebuf={pc:", hex(morebuf.pc), " sp:", hex(morebuf.sp), " lr:", hex(morebuf.lr), "}\n",
-			"\tsched={pc:", hex(gp.sched.pc), " sp:", hex(gp.sched.sp), " lr:", hex(gp.sched.lr), " ctxt:", gp.sched.ctxt, "}\n")
-	}
-	if sp < gp.stack.lo {
-		print("runtime: gp=", gp, ", goid=", gp.goid, ", gp->status=", hex(readgstatus(gp)), "\n ")
-		print("runtime: split stack overflow: ", hex(sp), " < ", hex(gp.stack.lo), "\n")
-		throw("runtime: split stack overflow")
-	}
-
-	if preempt {
-		if gp == thisg.m.g0 {
-			throw("runtime: preempt g0")
-		}
-		if thisg.m.p == 0 && thisg.m.locks == 0 {
-			throw("runtime: g is running but p is not")
-		}
-
-		if gp.preemptShrink {
-			// We're at a synchronous safe point now, so
-			// do the pending stack shrink.
-			gp.preemptShrink = false
-			shrinkstack(gp)
-		}
-
-		if gp.preemptStop {
-			preemptPark(gp) // never returns
-		}
-
-		// Act like goroutine called runtime.Gosched.
-		gopreempt_m(gp) // never return
-	}
-
-	// Allocate a bigger segment and move the stack.
-	oldsize := gp.stack.hi - gp.stack.lo
-	newsize := oldsize * 2
-
-	// Make sure we grow at least as much as needed to fit the new frame.
-	// (This is just an optimization - the caller of morestack will
-	// recheck the bounds on return.)
-	if f := findfunc(gp.sched.pc); f.valid() {
-		max := uintptr(funcMaxSPDelta(f))
-		needed := max + _StackGuard
-		used := gp.stack.hi - gp.sched.sp
-		for newsize-used < needed {
-			newsize *= 2
-		}
-	}
-
-	if stackguard0 == stackForceMove {
-		// Forced stack movement used for debugging.
-		// Don't double the stack (or we may quickly run out
-		// if this is done repeatedly).
-		newsize = oldsize
-	}
-
-	if newsize > maxstacksize || newsize > maxstackceiling {
-		if maxstacksize < maxstackceiling {
-			print("runtime: goroutine stack exceeds ", maxstacksize, "-byte limit\n")
-		} else {
-			print("runtime: goroutine stack exceeds ", maxstackceiling, "-byte limit\n")
-		}
-		print("runtime: sp=", hex(sp), " stack=[", hex(gp.stack.lo), ", ", hex(gp.stack.hi), "]\n")
-		throw("stack overflow")
-	}
-
-	// The goroutine must be executing in order to call newstack,
-	// so it must be Grunning (or Gscanrunning).
-	casgstatus(gp, _Grunning, _Gcopystack)
-
-	// The concurrent GC will not scan the stack while we are doing the copy since
-	// the gp is in a Gcopystack status.
-	copystack(gp, newsize)
-	if stackDebug >= 1 {
-		print("stack grow done\n")
-	}
-	casgstatus(gp, _Gcopystack, _Grunning)
-	gogo(&gp.sched)
-}
-
-//go:nosplit
-func nilfunc() {
-	*(*uint8)(nil) = 0
-}
-
-// adjust Gobuf as if it executed a call to fn
-// and then stopped before the first instruction in fn.
-func gostartcallfn(gobuf *gobuf, fv *funcval) {
-	var fn unsafe.Pointer
-	if fv != nil {
-		fn = unsafe.Pointer(fv.fn)
-	} else {
-		fn = unsafe.Pointer(abi.FuncPCABIInternal(nilfunc))
-	}
-	gostartcall(gobuf, fn, unsafe.Pointer(fv))
-}
-
-// isShrinkStackSafe returns whether it's safe to attempt to shrink
-// gp's stack. Shrinking the stack is only safe when we have precise
-// pointer maps for all frames on the stack.
-func isShrinkStackSafe(gp *g) bool {
-	// We can't copy the stack if we're in a syscall.
-	// The syscall might have pointers into the stack and
-	// often we don't have precise pointer maps for the innermost
-	// frames.
-	//
-	// We also can't copy the stack if we're at an asynchronous
-	// safe-point because we don't have precise pointer maps for
-	// all frames.
-	//
-	// We also can't *shrink* the stack in the window between the
-	// goroutine calling gopark to park on a channel and
-	// gp.activeStackChans being set.
-	return gp.syscallsp == 0 && !gp.asyncSafePoint && atomic.Load8(&gp.parkingOnChan) == 0
-}
-
-// Maybe shrink the stack being used by gp.
-//
-// gp must be stopped and we must own its stack. It may be in
-// _Grunning, but only if this is our own user G.
-func shrinkstack(gp *g) {
-	if gp.stack.lo == 0 {
-		throw("missing stack in shrinkstack")
-	}
-	if s := readgstatus(gp); s&_Gscan == 0 {
-		// We don't own the stack via _Gscan. We could still
-		// own it if this is our own user G and we're on the
-		// system stack.
-		if !(gp == getg().m.curg && getg() != getg().m.curg && s == _Grunning) {
-			// We don't own the stack.
-			throw("bad status in shrinkstack")
-		}
-	}
-	if !isShrinkStackSafe(gp) {
-		throw("shrinkstack at bad time")
-	}
-	// Check for self-shrinks while in a libcall. These may have
-	// pointers into the stack disguised as uintptrs, but these
-	// code paths should all be nosplit.
-	if gp == getg().m.curg && gp.m.libcallsp != 0 {
-		throw("shrinking stack in libcall")
-	}
-
-	if debug.gcshrinkstackoff > 0 {
-		return
-	}
-	f := findfunc(gp.startpc)
-	if f.valid() && f.funcID == funcID_gcBgMarkWorker {
-		// We're not allowed to shrink the gcBgMarkWorker
-		// stack (see gcBgMarkWorker for explanation).
-		return
-	}
-
-	oldsize := gp.stack.hi - gp.stack.lo
-	newsize := oldsize / 2
-	// Don't shrink the allocation below the minimum-sized stack
-	// allocation.
-	if newsize < _FixedStack {
-		return
-	}
-	// Compute how much of the stack is currently in use and only
-	// shrink the stack if gp is using less than a quarter of its
-	// current stack. The currently used stack includes everything
-	// down to the SP plus the stack guard space that ensures
-	// there's room for nosplit functions.
-	avail := gp.stack.hi - gp.stack.lo
-	if used := gp.stack.hi - gp.sched.sp + _StackLimit; used >= avail/4 {
-		return
-	}
-
-	if stackDebug > 0 {
-		print("shrinking stack ", oldsize, "->", newsize, "\n")
-	}
-
-	copystack(gp, newsize)
-}
-
-// freeStackSpans frees unused stack spans at the end of GC.
-func freeStackSpans() {
-	// Scan stack pools for empty stack spans.
-	for order := range stackpool {
-		lock(&stackpool[order].item.mu)
-		list := &stackpool[order].item.span
-		for s := list.first; s != nil; {
-			next := s.next
-			if s.allocCount == 0 {
-				list.remove(s)
-				s.manualFreeList = 0
-				osStackFree(s)
-				mheap_.freeManual(s, spanAllocStack)
-			}
-			s = next
-		}
-		unlock(&stackpool[order].item.mu)
-	}
-
-	// Free large stack spans.
-	lock(&stackLarge.lock)
-	for i := range stackLarge.free {
-		for s := stackLarge.free[i].first; s != nil; {
-			next := s.next
-			stackLarge.free[i].remove(s)
-			osStackFree(s)
-			mheap_.freeManual(s, spanAllocStack)
-			s = next
-		}
-	}
-	unlock(&stackLarge.lock)
-}
-
-// getStackMap returns the locals and arguments live pointer maps, and
-// stack object list for frame.
-func getStackMap(frame *stkframe, cache *pcvalueCache, debug bool) (locals, args bitvector, objs []stackObjectRecord) {
-	targetpc := frame.continpc
-	if targetpc == 0 {
-		// Frame is dead. Return empty bitvectors.
-		return
-	}
-
-	f := frame.fn
-	pcdata := int32(-1)
-	if targetpc != f.entry() {
-		// Back up to the CALL. If we're at the function entry
-		// point, we want to use the entry map (-1), even if
-		// the first instruction of the function changes the
-		// stack map.
-		targetpc--
-		pcdata = pcdatavalue(f, _PCDATA_StackMapIndex, targetpc, cache)
-	}
-	if pcdata == -1 {
-		// We do not have a valid pcdata value but there might be a
-		// stackmap for this function. It is likely that we are looking
-		// at the function prologue, assume so and hope for the best.
-		pcdata = 0
-	}
-
-	// Local variables.
-	size := frame.varp - frame.sp
-	var minsize uintptr
-	switch goarch.ArchFamily {
-	case goarch.ARM64:
-		minsize = sys.StackAlign
-	default:
-		minsize = sys.MinFrameSize
-	}
-	if size > minsize {
-		stackid := pcdata
-		stkmap := (*stackmap)(funcdata(f, _FUNCDATA_LocalsPointerMaps))
-		if stkmap == nil || stkmap.n <= 0 {
-			print("runtime: frame ", funcname(f), " untyped locals ", hex(frame.varp-size), "+", hex(size), "\n")
-			throw("missing stackmap")
-		}
-		// If nbit == 0, there's no work to do.
-		if stkmap.nbit > 0 {
-			if stackid < 0 || stackid >= stkmap.n {
-				// don't know where we are
-				print("runtime: pcdata is ", stackid, " and ", stkmap.n, " locals stack map entries for ", funcname(f), " (targetpc=", hex(targetpc), ")\n")
-				throw("bad symbol table")
-			}
-			locals = stackmapdata(stkmap, stackid)
-			if stackDebug >= 3 && debug {
-				print("      locals ", stackid, "/", stkmap.n, " ", locals.n, " words ", locals.bytedata, "\n")
-			}
-		} else if stackDebug >= 3 && debug {
-			print("      no locals to adjust\n")
-		}
-	}
-
-	// Arguments.
-	if frame.arglen > 0 {
-		if frame.argmap != nil {
-			// argmap is set when the function is reflect.makeFuncStub or reflect.methodValueCall.
-			// In this case, arglen specifies how much of the args section is actually live.
-			// (It could be either all the args + results, or just the args.)
-			args = *frame.argmap
-			n := int32(frame.arglen / goarch.PtrSize)
-			if n < args.n {
-				args.n = n // Don't use more of the arguments than arglen.
-			}
-		} else {
-			stackmap := (*stackmap)(funcdata(f, _FUNCDATA_ArgsPointerMaps))
-			if stackmap == nil || stackmap.n <= 0 {
-				print("runtime: frame ", funcname(f), " untyped args ", hex(frame.argp), "+", hex(frame.arglen), "\n")
-				throw("missing stackmap")
-			}
-			if pcdata < 0 || pcdata >= stackmap.n {
-				// don't know where we are
-				print("runtime: pcdata is ", pcdata, " and ", stackmap.n, " args stack map entries for ", funcname(f), " (targetpc=", hex(targetpc), ")\n")
-				throw("bad symbol table")
-			}
-			if stackmap.nbit > 0 {
-				args = stackmapdata(stackmap, pcdata)
-			}
-		}
-	}
-
-	// stack objects.
-	if (GOARCH == "amd64" || GOARCH == "arm64" || GOARCH == "ppc64" || GOARCH == "ppc64le") && unsafe.Sizeof(abi.RegArgs{}) > 0 && frame.argmap != nil {
-		// argmap is set when the function is reflect.makeFuncStub or reflect.methodValueCall.
-		// We don't actually use argmap in this case, but we need to fake the stack object
-		// record for these frames which contain an internal/abi.RegArgs at a hard-coded offset.
-		// This offset matches the assembly code on amd64 and arm64.
-		objs = methodValueCallFrameObjs[:]
-	} else {
-		p := funcdata(f, _FUNCDATA_StackObjects)
-		if p != nil {
-			n := *(*uintptr)(p)
-			p = add(p, goarch.PtrSize)
-			*(*slice)(unsafe.Pointer(&objs)) = slice{array: noescape(p), len: int(n), cap: int(n)}
-			// Note: the noescape above is needed to keep
-			// getStackMap from "leaking param content:
-			// frame".  That leak propagates up to getgcmask, then
-			// GCMask, then verifyGCInfo, which converts the stack
-			// gcinfo tests into heap gcinfo tests :(
-		}
-	}
-
-	return
-}
-
-var methodValueCallFrameObjs [1]stackObjectRecord // initialized in stackobjectinit
-
-func stkobjinit() {
-	var abiRegArgsEface any = abi.RegArgs{}
-	abiRegArgsType := efaceOf(&abiRegArgsEface)._type
-	if abiRegArgsType.kind&kindGCProg != 0 {
-		throw("abiRegArgsType needs GC Prog, update methodValueCallFrameObjs")
-	}
-	// Set methodValueCallFrameObjs[0].gcdataoff so that
-	// stackObjectRecord.gcdata() will work correctly with it.
-	ptr := uintptr(unsafe.Pointer(&methodValueCallFrameObjs[0]))
-	var mod *moduledata
-	for datap := &firstmoduledata; datap != nil; datap = datap.next {
-		if datap.gofunc <= ptr && ptr < datap.end {
-			mod = datap
-			break
-		}
-	}
-	if mod == nil {
-		throw("methodValueCallFrameObjs is not in a module")
-	}
-	methodValueCallFrameObjs[0] = stackObjectRecord{
-		off:       -int32(alignUp(abiRegArgsType.size, 8)), // It's always the highest address local.
-		size:      int32(abiRegArgsType.size),
-		_ptrdata:  int32(abiRegArgsType.ptrdata),
-		gcdataoff: uint32(uintptr(unsafe.Pointer(abiRegArgsType.gcdata)) - mod.rodata),
-	}
-}
-
-// A stackObjectRecord is generated by the compiler for each stack object in a stack frame.
-// This record must match the generator code in cmd/compile/internal/liveness/plive.go:emitStackObjects.
-type stackObjectRecord struct {
-	// offset in frame
-	// if negative, offset from varp
-	// if non-negative, offset from argp
-	off       int32
-	size      int32
-	_ptrdata  int32  // ptrdata, or -ptrdata is GC prog is used
-	gcdataoff uint32 // offset to gcdata from moduledata.rodata
-}
-
-func (r *stackObjectRecord) useGCProg() bool {
-	return r._ptrdata < 0
-}
-
-func (r *stackObjectRecord) ptrdata() uintptr {
-	x := r._ptrdata
-	if x < 0 {
-		return uintptr(-x)
-	}
-	return uintptr(x)
-}
-
-// gcdata returns pointer map or GC prog of the type.
-func (r *stackObjectRecord) gcdata() *byte {
-	ptr := uintptr(unsafe.Pointer(r))
-	var mod *moduledata
-	for datap := &firstmoduledata; datap != nil; datap = datap.next {
-		if datap.gofunc <= ptr && ptr < datap.end {
-			mod = datap
-			break
-		}
-	}
-	// If you get a panic here due to a nil mod,
-	// you may have made a copy of a stackObjectRecord.
-	// You must use the original pointer.
-	res := mod.rodata + uintptr(r.gcdataoff)
-	return (*byte)(unsafe.Pointer(res))
-}
-
-// This is exported as ABI0 via linkname so obj can call it.
-//
-//go:nosplit
-//go:linkname morestackc
-func morestackc() {
-	throw("attempt to execute system stack code on user stack")
-}
diff --git a/contrib/go/_std_1.18/src/runtime/string.go b/contrib/go/_std_1.18/src/runtime/string.go
deleted file mode 100644
index 980a9866e6..0000000000
--- a/contrib/go/_std_1.18/src/runtime/string.go
+++ /dev/null
@@ -1,495 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"internal/abi"
-	"internal/bytealg"
-	"internal/goarch"
-	"unsafe"
-)
-
-// The constant is known to the compiler.
-// There is no fundamental theory behind this number.
-const tmpStringBufSize = 32
-
-type tmpBuf [tmpStringBufSize]byte
-
-// concatstrings implements a Go string concatenation x+y+z+...
-// The operands are passed in the slice a.
-// If buf != nil, the compiler has determined that the result does not
-// escape the calling function, so the string data can be stored in buf
-// if small enough.
-func concatstrings(buf *tmpBuf, a []string) string {
-	idx := 0
-	l := 0
-	count := 0
-	for i, x := range a {
-		n := len(x)
-		if n == 0 {
-			continue
-		}
-		if l+n < l {
-			throw("string concatenation too long")
-		}
-		l += n
-		count++
-		idx = i
-	}
-	if count == 0 {
-		return ""
-	}
-
-	// If there is just one string and either it is not on the stack
-	// or our result does not escape the calling frame (buf != nil),
-	// then we can return that string directly.
-	if count == 1 && (buf != nil || !stringDataOnStack(a[idx])) {
-		return a[idx]
-	}
-	s, b := rawstringtmp(buf, l)
-	for _, x := range a {
-		copy(b, x)
-		b = b[len(x):]
-	}
-	return s
-}
-
-func concatstring2(buf *tmpBuf, a0, a1 string) string {
-	return concatstrings(buf, []string{a0, a1})
-}
-
-func concatstring3(buf *tmpBuf, a0, a1, a2 string) string {
-	return concatstrings(buf, []string{a0, a1, a2})
-}
-
-func concatstring4(buf *tmpBuf, a0, a1, a2, a3 string) string {
-	return concatstrings(buf, []string{a0, a1, a2, a3})
-}
-
-func concatstring5(buf *tmpBuf, a0, a1, a2, a3, a4 string) string {
-	return concatstrings(buf, []string{a0, a1, a2, a3, a4})
-}
-
-// slicebytetostring converts a byte slice to a string.
-// It is inserted by the compiler into generated code.
-// ptr is a pointer to the first element of the slice;
-// n is the length of the slice.
-// Buf is a fixed-size buffer for the result,
-// it is not nil if the result does not escape.
-func slicebytetostring(buf *tmpBuf, ptr *byte, n int) (str string) {
-	if n == 0 {
-		// Turns out to be a relatively common case.
-		// Consider that you want to parse out data between parens in "foo()bar",
-		// you find the indices and convert the subslice to string.
-		return ""
-	}
-	if raceenabled {
-		racereadrangepc(unsafe.Pointer(ptr),
-			uintptr(n),
-			getcallerpc(),
-			abi.FuncPCABIInternal(slicebytetostring))
-	}
-	if msanenabled {
-		msanread(unsafe.Pointer(ptr), uintptr(n))
-	}
-	if asanenabled {
-		asanread(unsafe.Pointer(ptr), uintptr(n))
-	}
-	if n == 1 {
-		p := unsafe.Pointer(&staticuint64s[*ptr])
-		if goarch.BigEndian {
-			p = add(p, 7)
-		}
-		stringStructOf(&str).str = p
-		stringStructOf(&str).len = 1
-		return
-	}
-
-	var p unsafe.Pointer
-	if buf != nil && n <= len(buf) {
-		p = unsafe.Pointer(buf)
-	} else {
-		p = mallocgc(uintptr(n), nil, false)
-	}
-	stringStructOf(&str).str = p
-	stringStructOf(&str).len = n
-	memmove(p, unsafe.Pointer(ptr), uintptr(n))
-	return
-}
-
-// stringDataOnStack reports whether the string's data is
-// stored on the current goroutine's stack.
-func stringDataOnStack(s string) bool {
-	ptr := uintptr(stringStructOf(&s).str)
-	stk := getg().stack
-	return stk.lo <= ptr && ptr < stk.hi
-}
-
-func rawstringtmp(buf *tmpBuf, l int) (s string, b []byte) {
-	if buf != nil && l <= len(buf) {
-		b = buf[:l]
-		s = slicebytetostringtmp(&b[0], len(b))
-	} else {
-		s, b = rawstring(l)
-	}
-	return
-}
-
-// slicebytetostringtmp returns a "string" referring to the actual []byte bytes.
-//
-// Callers need to ensure that the returned string will not be used after
-// the calling goroutine modifies the original slice or synchronizes with
-// another goroutine.
-//
-// The function is only called when instrumenting
-// and otherwise intrinsified by the compiler.
-//
-// Some internal compiler optimizations use this function.
-// - Used for m[T1{... Tn{..., string(k), ...} ...}] and m[string(k)]
-//   where k is []byte, T1 to Tn is a nesting of struct and array literals.
-// - Used for "<"+string(b)+">" concatenation where b is []byte.
-// - Used for string(b)=="foo" comparison where b is []byte.
-func slicebytetostringtmp(ptr *byte, n int) (str string) {
-	if raceenabled && n > 0 {
-		racereadrangepc(unsafe.Pointer(ptr),
-			uintptr(n),
-			getcallerpc(),
-			abi.FuncPCABIInternal(slicebytetostringtmp))
-	}
-	if msanenabled && n > 0 {
-		msanread(unsafe.Pointer(ptr), uintptr(n))
-	}
-	if asanenabled && n > 0 {
-		asanread(unsafe.Pointer(ptr), uintptr(n))
-	}
-	stringStructOf(&str).str = unsafe.Pointer(ptr)
-	stringStructOf(&str).len = n
-	return
-}
-
-func stringtoslicebyte(buf *tmpBuf, s string) []byte {
-	var b []byte
-	if buf != nil && len(s) <= len(buf) {
-		*buf = tmpBuf{}
-		b = buf[:len(s)]
-	} else {
-		b = rawbyteslice(len(s))
-	}
-	copy(b, s)
-	return b
-}
-
-func stringtoslicerune(buf *[tmpStringBufSize]rune, s string) []rune {
-	// two passes.
-	// unlike slicerunetostring, no race because strings are immutable.
-	n := 0
-	for range s {
-		n++
-	}
-
-	var a []rune
-	if buf != nil && n <= len(buf) {
-		*buf = [tmpStringBufSize]rune{}
-		a = buf[:n]
-	} else {
-		a = rawruneslice(n)
-	}
-
-	n = 0
-	for _, r := range s {
-		a[n] = r
-		n++
-	}
-	return a
-}
-
-func slicerunetostring(buf *tmpBuf, a []rune) string {
-	if raceenabled && len(a) > 0 {
-		racereadrangepc(unsafe.Pointer(&a[0]),
-			uintptr(len(a))*unsafe.Sizeof(a[0]),
-			getcallerpc(),
-			abi.FuncPCABIInternal(slicerunetostring))
-	}
-	if msanenabled && len(a) > 0 {
-		msanread(unsafe.Pointer(&a[0]), uintptr(len(a))*unsafe.Sizeof(a[0]))
-	}
-	if asanenabled && len(a) > 0 {
-		asanread(unsafe.Pointer(&a[0]), uintptr(len(a))*unsafe.Sizeof(a[0]))
-	}
-	var dum [4]byte
-	size1 := 0
-	for _, r := range a {
-		size1 += encoderune(dum[:], r)
-	}
-	s, b := rawstringtmp(buf, size1+3)
-	size2 := 0
-	for _, r := range a {
-		// check for race
-		if size2 >= size1 {
-			break
-		}
-		size2 += encoderune(b[size2:], r)
-	}
-	return s[:size2]
-}
-
-type stringStruct struct {
-	str unsafe.Pointer
-	len int
-}
-
-// Variant with *byte pointer type for DWARF debugging.
-type stringStructDWARF struct {
-	str *byte
-	len int
-}
-
-func stringStructOf(sp *string) *stringStruct {
-	return (*stringStruct)(unsafe.Pointer(sp))
-}
-
-func intstring(buf *[4]byte, v int64) (s string) {
-	var b []byte
-	if buf != nil {
-		b = buf[:]
-		s = slicebytetostringtmp(&b[0], len(b))
-	} else {
-		s, b = rawstring(4)
-	}
-	if int64(rune(v)) != v {
-		v = runeError
-	}
-	n := encoderune(b, rune(v))
-	return s[:n]
-}
-
-// rawstring allocates storage for a new string. The returned
-// string and byte slice both refer to the same storage.
-// The storage is not zeroed. Callers should use
-// b to set the string contents and then drop b.
-func rawstring(size int) (s string, b []byte) {
-	p := mallocgc(uintptr(size), nil, false)
-
-	stringStructOf(&s).str = p
-	stringStructOf(&s).len = size
-
-	*(*slice)(unsafe.Pointer(&b)) = slice{p, size, size}
-
-	return
-}
-
-// rawbyteslice allocates a new byte slice. The byte slice is not zeroed.
-func rawbyteslice(size int) (b []byte) {
-	cap := roundupsize(uintptr(size))
-	p := mallocgc(cap, nil, false)
-	if cap != uintptr(size) {
-		memclrNoHeapPointers(add(p, uintptr(size)), cap-uintptr(size))
-	}
-
-	*(*slice)(unsafe.Pointer(&b)) = slice{p, size, int(cap)}
-	return
-}
-
-// rawruneslice allocates a new rune slice. The rune slice is not zeroed.
-func rawruneslice(size int) (b []rune) {
-	if uintptr(size) > maxAlloc/4 {
-		throw("out of memory")
-	}
-	mem := roundupsize(uintptr(size) * 4)
-	p := mallocgc(mem, nil, false)
-	if mem != uintptr(size)*4 {
-		memclrNoHeapPointers(add(p, uintptr(size)*4), mem-uintptr(size)*4)
-	}
-
-	*(*slice)(unsafe.Pointer(&b)) = slice{p, size, int(mem / 4)}
-	return
-}
-
-// used by cmd/cgo
-func gobytes(p *byte, n int) (b []byte) {
-	if n == 0 {
-		return make([]byte, 0)
-	}
-
-	if n < 0 || uintptr(n) > maxAlloc {
-		panic(errorString("gobytes: length out of range"))
-	}
-
-	bp := mallocgc(uintptr(n), nil, false)
-	memmove(bp, unsafe.Pointer(p), uintptr(n))
-
-	*(*slice)(unsafe.Pointer(&b)) = slice{bp, n, n}
-	return
-}
-
-// This is exported via linkname to assembly in syscall (for Plan9).
-//go:linkname gostring
-func gostring(p *byte) string {
-	l := findnull(p)
-	if l == 0 {
-		return ""
-	}
-	s, b := rawstring(l)
-	memmove(unsafe.Pointer(&b[0]), unsafe.Pointer(p), uintptr(l))
-	return s
-}
-
-func gostringn(p *byte, l int) string {
-	if l == 0 {
-		return ""
-	}
-	s, b := rawstring(l)
-	memmove(unsafe.Pointer(&b[0]), unsafe.Pointer(p), uintptr(l))
-	return s
-}
-
-func hasPrefix(s, prefix string) bool {
-	return len(s) >= len(prefix) && s[:len(prefix)] == prefix
-}
-
-const (
-	maxUint = ^uint(0)
-	maxInt  = int(maxUint >> 1)
-)
-
-// atoi parses an int from a string s.
-// The bool result reports whether s is a number
-// representable by a value of type int.
-func atoi(s string) (int, bool) {
-	if s == "" {
-		return 0, false
-	}
-
-	neg := false
-	if s[0] == '-' {
-		neg = true
-		s = s[1:]
-	}
-
-	un := uint(0)
-	for i := 0; i < len(s); i++ {
-		c := s[i]
-		if c < '0' || c > '9' {
-			return 0, false
-		}
-		if un > maxUint/10 {
-			// overflow
-			return 0, false
-		}
-		un *= 10
-		un1 := un + uint(c) - '0'
-		if un1 < un {
-			// overflow
-			return 0, false
-		}
-		un = un1
-	}
-
-	if !neg && un > uint(maxInt) {
-		return 0, false
-	}
-	if neg && un > uint(maxInt)+1 {
-		return 0, false
-	}
-
-	n := int(un)
-	if neg {
-		n = -n
-	}
-
-	return n, true
-}
-
-// atoi32 is like atoi but for integers
-// that fit into an int32.
-func atoi32(s string) (int32, bool) {
-	if n, ok := atoi(s); n == int(int32(n)) {
-		return int32(n), ok
-	}
-	return 0, false
-}
-
-//go:nosplit
-func findnull(s *byte) int {
-	if s == nil {
-		return 0
-	}
-
-	// Avoid IndexByteString on Plan 9 because it uses SSE instructions
-	// on x86 machines, and those are classified as floating point instructions,
-	// which are illegal in a note handler.
-	if GOOS == "plan9" {
-		p := (*[maxAlloc/2 - 1]byte)(unsafe.Pointer(s))
-		l := 0
-		for p[l] != 0 {
-			l++
-		}
-		return l
-	}
-
-	// pageSize is the unit we scan at a time looking for NULL.
-	// It must be the minimum page size for any architecture Go
-	// runs on. It's okay (just a minor performance loss) if the
-	// actual system page size is larger than this value.
-	const pageSize = 4096
-
-	offset := 0
-	ptr := unsafe.Pointer(s)
-	// IndexByteString uses wide reads, so we need to be careful
-	// with page boundaries. Call IndexByteString on
-	// [ptr, endOfPage) interval.
-	safeLen := int(pageSize - uintptr(ptr)%pageSize)
-
-	for {
-		t := *(*string)(unsafe.Pointer(&stringStruct{ptr, safeLen}))
-		// Check one page at a time.
-		if i := bytealg.IndexByteString(t, 0); i != -1 {
-			return offset + i
-		}
-		// Move to next page
-		ptr = unsafe.Pointer(uintptr(ptr) + uintptr(safeLen))
-		offset += safeLen
-		safeLen = pageSize
-	}
-}
-
-func findnullw(s *uint16) int {
-	if s == nil {
-		return 0
-	}
-	p := (*[maxAlloc/2/2 - 1]uint16)(unsafe.Pointer(s))
-	l := 0
-	for p[l] != 0 {
-		l++
-	}
-	return l
-}
-
-//go:nosplit
-func gostringnocopy(str *byte) string {
-	ss := stringStruct{str: unsafe.Pointer(str), len: findnull(str)}
-	s := *(*string)(unsafe.Pointer(&ss))
-	return s
-}
-
-func gostringw(strw *uint16) string {
-	var buf [8]byte
-	str := (*[maxAlloc/2/2 - 1]uint16)(unsafe.Pointer(strw))
-	n1 := 0
-	for i := 0; str[i] != 0; i++ {
-		n1 += encoderune(buf[:], rune(str[i]))
-	}
-	s, b := rawstring(n1 + 4)
-	n2 := 0
-	for i := 0; str[i] != 0; i++ {
-		// check for race
-		if n2 >= n1 {
-			break
-		}
-		n2 += encoderune(b[n2:], rune(str[i]))
-	}
-	b[n2] = 0 // for luck
-	return s[:n2]
-}
diff --git a/contrib/go/_std_1.18/src/runtime/stubs.go b/contrib/go/_std_1.18/src/runtime/stubs.go
deleted file mode 100644
index ad78363bb6..0000000000
--- a/contrib/go/_std_1.18/src/runtime/stubs.go
+++ /dev/null
@@ -1,437 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"internal/abi"
-	"internal/goarch"
-	"internal/goexperiment"
-	"runtime/internal/math"
-	"unsafe"
-)
-
-// Should be a built-in for unsafe.Pointer?
-//go:nosplit
-func add(p unsafe.Pointer, x uintptr) unsafe.Pointer {
-	return unsafe.Pointer(uintptr(p) + x)
-}
-
-// getg returns the pointer to the current g.
-// The compiler rewrites calls to this function into instructions
-// that fetch the g directly (from TLS or from the dedicated register).
-func getg() *g
-
-// mcall switches from the g to the g0 stack and invokes fn(g),
-// where g is the goroutine that made the call.
-// mcall saves g's current PC/SP in g->sched so that it can be restored later.
-// It is up to fn to arrange for that later execution, typically by recording
-// g in a data structure, causing something to call ready(g) later.
-// mcall returns to the original goroutine g later, when g has been rescheduled.
-// fn must not return at all; typically it ends by calling schedule, to let the m
-// run other goroutines.
-//
-// mcall can only be called from g stacks (not g0, not gsignal).
-//
-// This must NOT be go:noescape: if fn is a stack-allocated closure,
-// fn puts g on a run queue, and g executes before fn returns, the
-// closure will be invalidated while it is still executing.
-func mcall(fn func(*g))
-
-// systemstack runs fn on a system stack.
-// If systemstack is called from the per-OS-thread (g0) stack, or
-// if systemstack is called from the signal handling (gsignal) stack,
-// systemstack calls fn directly and returns.
-// Otherwise, systemstack is being called from the limited stack
-// of an ordinary goroutine. In this case, systemstack switches
-// to the per-OS-thread stack, calls fn, and switches back.
-// It is common to use a func literal as the argument, in order
-// to share inputs and outputs with the code around the call
-// to system stack:
-//
-//	... set up y ...
-//	systemstack(func() {
-//		x = bigcall(y)
-//	})
-//	... use x ...
-//
-//go:noescape
-func systemstack(fn func())
-
-var badsystemstackMsg = "fatal: systemstack called from unexpected goroutine"
-
-//go:nosplit
-//go:nowritebarrierrec
-func badsystemstack() {
-	sp := stringStructOf(&badsystemstackMsg)
-	write(2, sp.str, int32(sp.len))
-}
-
-// memclrNoHeapPointers clears n bytes starting at ptr.
-//
-// Usually you should use typedmemclr. memclrNoHeapPointers should be
-// used only when the caller knows that *ptr contains no heap pointers
-// because either:
-//
-// *ptr is initialized memory and its type is pointer-free, or
-//
-// *ptr is uninitialized memory (e.g., memory that's being reused
-// for a new allocation) and hence contains only "junk".
-//
-// memclrNoHeapPointers ensures that if ptr is pointer-aligned, and n
-// is a multiple of the pointer size, then any pointer-aligned,
-// pointer-sized portion is cleared atomically. Despite the function
-// name, this is necessary because this function is the underlying
-// implementation of typedmemclr and memclrHasPointers. See the doc of
-// memmove for more details.
-//
-// The (CPU-specific) implementations of this function are in memclr_*.s.
-//
-//go:noescape
-func memclrNoHeapPointers(ptr unsafe.Pointer, n uintptr)
-
-//go:linkname reflect_memclrNoHeapPointers reflect.memclrNoHeapPointers
-func reflect_memclrNoHeapPointers(ptr unsafe.Pointer, n uintptr) {
-	memclrNoHeapPointers(ptr, n)
-}
-
-// memmove copies n bytes from "from" to "to".
-//
-// memmove ensures that any pointer in "from" is written to "to" with
-// an indivisible write, so that racy reads cannot observe a
-// half-written pointer. This is necessary to prevent the garbage
-// collector from observing invalid pointers, and differs from memmove
-// in unmanaged languages. However, memmove is only required to do
-// this if "from" and "to" may contain pointers, which can only be the
-// case if "from", "to", and "n" are all be word-aligned.
-//
-// Implementations are in memmove_*.s.
-//
-//go:noescape
-func memmove(to, from unsafe.Pointer, n uintptr)
-
-// Outside assembly calls memmove. Make sure it has ABI wrappers.
-//go:linkname memmove
-
-//go:linkname reflect_memmove reflect.memmove
-func reflect_memmove(to, from unsafe.Pointer, n uintptr) {
-	memmove(to, from, n)
-}
-
-// exported value for testing
-const hashLoad = float32(loadFactorNum) / float32(loadFactorDen)
-
-//go:nosplit
-func fastrand() uint32 {
-	mp := getg().m
-	// Implement wyrand: https://github.com/wangyi-fudan/wyhash
-	// Only the platform that math.Mul64 can be lowered
-	// by the compiler should be in this list.
-	if goarch.IsAmd64|goarch.IsArm64|goarch.IsPpc64|
-		goarch.IsPpc64le|goarch.IsMips64|goarch.IsMips64le|
-		goarch.IsS390x|goarch.IsRiscv64 == 1 {
-		mp.fastrand += 0xa0761d6478bd642f
-		hi, lo := math.Mul64(mp.fastrand, mp.fastrand^0xe7037ed1a0b428db)
-		return uint32(hi ^ lo)
-	}
-
-	// Implement xorshift64+: 2 32-bit xorshift sequences added together.
-	// Shift triplet [17,7,16] was calculated as indicated in Marsaglia's
-	// Xorshift paper: https://www.jstatsoft.org/article/view/v008i14/xorshift.pdf
-	// This generator passes the SmallCrush suite, part of TestU01 framework:
-	// http://simul.iro.umontreal.ca/testu01/tu01.html
-	t := (*[2]uint32)(unsafe.Pointer(&mp.fastrand))
-	s1, s0 := t[0], t[1]
-	s1 ^= s1 << 17
-	s1 = s1 ^ s0 ^ s1>>7 ^ s0>>16
-	t[0], t[1] = s0, s1
-	return s0 + s1
-}
-
-//go:nosplit
-func fastrandn(n uint32) uint32 {
-	// This is similar to fastrand() % n, but faster.
-	// See https://lemire.me/blog/2016/06/27/a-fast-alternative-to-the-modulo-reduction/
-	return uint32(uint64(fastrand()) * uint64(n) >> 32)
-}
-
-//go:linkname sync_fastrandn sync.fastrandn
-func sync_fastrandn(n uint32) uint32 { return fastrandn(n) }
-
-//go:linkname net_fastrand net.fastrand
-func net_fastrand() uint32 { return fastrand() }
-
-//go:linkname os_fastrand os.fastrand
-func os_fastrand() uint32 { return fastrand() }
-
-// in internal/bytealg/equal_*.s
-//go:noescape
-func memequal(a, b unsafe.Pointer, size uintptr) bool
-
-// noescape hides a pointer from escape analysis.  noescape is
-// the identity function but escape analysis doesn't think the
-// output depends on the input.  noescape is inlined and currently
-// compiles down to zero instructions.
-// USE CAREFULLY!
-//go:nosplit
-func noescape(p unsafe.Pointer) unsafe.Pointer {
-	x := uintptr(p)
-	return unsafe.Pointer(x ^ 0)
-}
-
-// Not all cgocallback frames are actually cgocallback,
-// so not all have these arguments. Mark them uintptr so that the GC
-// does not misinterpret memory when the arguments are not present.
-// cgocallback is not called from Go, only from crosscall2.
-// This in turn calls cgocallbackg, which is where we'll find
-// pointer-declared arguments.
-func cgocallback(fn, frame, ctxt uintptr)
-
-func gogo(buf *gobuf)
-
-func asminit()
-func setg(gg *g)
-func breakpoint()
-
-// reflectcall calls fn with arguments described by stackArgs, stackArgsSize,
-// frameSize, and regArgs.
-//
-// Arguments passed on the stack and space for return values passed on the stack
-// must be laid out at the space pointed to by stackArgs (with total length
-// stackArgsSize) according to the ABI.
-//
-// stackRetOffset must be some value <= stackArgsSize that indicates the
-// offset within stackArgs where the return value space begins.
-//
-// frameSize is the total size of the argument frame at stackArgs and must
-// therefore be >= stackArgsSize. It must include additional space for spilling
-// register arguments for stack growth and preemption.
-//
-// TODO(mknyszek): Once we don't need the additional spill space, remove frameSize,
-// since frameSize will be redundant with stackArgsSize.
-//
-// Arguments passed in registers must be laid out in regArgs according to the ABI.
-// regArgs will hold any return values passed in registers after the call.
-//
-// reflectcall copies stack arguments from stackArgs to the goroutine stack, and
-// then copies back stackArgsSize-stackRetOffset bytes back to the return space
-// in stackArgs once fn has completed. It also "unspills" argument registers from
-// regArgs before calling fn, and spills them back into regArgs immediately
-// following the call to fn. If there are results being returned on the stack,
-// the caller should pass the argument frame type as stackArgsType so that
-// reflectcall can execute appropriate write barriers during the copy.
-//
-// reflectcall expects regArgs.ReturnIsPtr to be populated indicating which
-// registers on the return path will contain Go pointers. It will then store
-// these pointers in regArgs.Ptrs such that they are visible to the GC.
-//
-// Package reflect passes a frame type. In package runtime, there is only
-// one call that copies results back, in callbackWrap in syscall_windows.go, and it
-// does NOT pass a frame type, meaning there are no write barriers invoked. See that
-// call site for justification.
-//
-// Package reflect accesses this symbol through a linkname.
-//
-// Arguments passed through to reflectcall do not escape. The type is used
-// only in a very limited callee of reflectcall, the stackArgs are copied, and
-// regArgs is only used in the reflectcall frame.
-//go:noescape
-func reflectcall(stackArgsType *_type, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-
-func procyield(cycles uint32)
-
-type neverCallThisFunction struct{}
-
-// goexit is the return stub at the top of every goroutine call stack.
-// Each goroutine stack is constructed as if goexit called the
-// goroutine's entry point function, so that when the entry point
-// function returns, it will return to goexit, which will call goexit1
-// to perform the actual exit.
-//
-// This function must never be called directly. Call goexit1 instead.
-// gentraceback assumes that goexit terminates the stack. A direct
-// call on the stack will cause gentraceback to stop walking the stack
-// prematurely and if there is leftover state it may panic.
-func goexit(neverCallThisFunction)
-
-// publicationBarrier performs a store/store barrier (a "publication"
-// or "export" barrier). Some form of synchronization is required
-// between initializing an object and making that object accessible to
-// another processor. Without synchronization, the initialization
-// writes and the "publication" write may be reordered, allowing the
-// other processor to follow the pointer and observe an uninitialized
-// object. In general, higher-level synchronization should be used,
-// such as locking or an atomic pointer write. publicationBarrier is
-// for when those aren't an option, such as in the implementation of
-// the memory manager.
-//
-// There's no corresponding barrier for the read side because the read
-// side naturally has a data dependency order. All architectures that
-// Go supports or seems likely to ever support automatically enforce
-// data dependency ordering.
-func publicationBarrier()
-
-// getcallerpc returns the program counter (PC) of its caller's caller.
-// getcallersp returns the stack pointer (SP) of its caller's caller.
-// The implementation may be a compiler intrinsic; there is not
-// necessarily code implementing this on every platform.
-//
-// For example:
-//
-//	func f(arg1, arg2, arg3 int) {
-//		pc := getcallerpc()
-//		sp := getcallersp()
-//	}
-//
-// These two lines find the PC and SP immediately following
-// the call to f (where f will return).
-//
-// The call to getcallerpc and getcallersp must be done in the
-// frame being asked about.
-//
-// The result of getcallersp is correct at the time of the return,
-// but it may be invalidated by any subsequent call to a function
-// that might relocate the stack in order to grow or shrink it.
-// A general rule is that the result of getcallersp should be used
-// immediately and can only be passed to nosplit functions.
-
-//go:noescape
-func getcallerpc() uintptr
-
-//go:noescape
-func getcallersp() uintptr // implemented as an intrinsic on all platforms
-
-// getclosureptr returns the pointer to the current closure.
-// getclosureptr can only be used in an assignment statement
-// at the entry of a function. Moreover, go:nosplit directive
-// must be specified at the declaration of caller function,
-// so that the function prolog does not clobber the closure register.
-// for example:
-//
-//	//go:nosplit
-//	func f(arg1, arg2, arg3 int) {
-//		dx := getclosureptr()
-//	}
-//
-// The compiler rewrites calls to this function into instructions that fetch the
-// pointer from a well-known register (DX on x86 architecture, etc.) directly.
-func getclosureptr() uintptr
-
-//go:noescape
-func asmcgocall(fn, arg unsafe.Pointer) int32
-
-func morestack()
-func morestack_noctxt()
-func rt0_go()
-
-// return0 is a stub used to return 0 from deferproc.
-// It is called at the very end of deferproc to signal
-// the calling Go function that it should not jump
-// to deferreturn.
-// in asm_*.s
-func return0()
-
-// in asm_*.s
-// not called directly; definitions here supply type information for traceback.
-// These must have the same signature (arg pointer map) as reflectcall.
-func call16(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-func call32(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-func call64(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-func call128(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-func call256(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-func call512(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-func call1024(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-func call2048(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-func call4096(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-func call8192(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-func call16384(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-func call32768(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-func call65536(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-func call131072(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-func call262144(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-func call524288(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-func call1048576(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-func call2097152(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-func call4194304(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-func call8388608(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-func call16777216(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-func call33554432(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-func call67108864(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-func call134217728(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-func call268435456(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-func call536870912(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-func call1073741824(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
-
-func systemstack_switch()
-
-// alignUp rounds n up to a multiple of a. a must be a power of 2.
-func alignUp(n, a uintptr) uintptr {
-	return (n + a - 1) &^ (a - 1)
-}
-
-// alignDown rounds n down to a multiple of a. a must be a power of 2.
-func alignDown(n, a uintptr) uintptr {
-	return n &^ (a - 1)
-}
-
-// divRoundUp returns ceil(n / a).
-func divRoundUp(n, a uintptr) uintptr {
-	// a is generally a power of two. This will get inlined and
-	// the compiler will optimize the division.
-	return (n + a - 1) / a
-}
-
-// checkASM reports whether assembly runtime checks have passed.
-func checkASM() bool
-
-func memequal_varlen(a, b unsafe.Pointer) bool
-
-// bool2int returns 0 if x is false or 1 if x is true.
-func bool2int(x bool) int {
-	// Avoid branches. In the SSA compiler, this compiles to
-	// exactly what you would want it to.
-	return int(uint8(*(*uint8)(unsafe.Pointer(&x))))
-}
-
-// abort crashes the runtime in situations where even throw might not
-// work. In general it should do something a debugger will recognize
-// (e.g., an INT3 on x86). A crash in abort is recognized by the
-// signal handler, which will attempt to tear down the runtime
-// immediately.
-func abort()
-
-// Called from compiled code; declared for vet; do NOT call from Go.
-func gcWriteBarrier()
-func duffzero()
-func duffcopy()
-
-// Called from linker-generated .initarray; declared for go vet; do NOT call from Go.
-func addmoduledata()
-
-// Injected by the signal handler for panicking signals.
-// Initializes any registers that have fixed meaning at calls but
-// are scratch in bodies and calls sigpanic.
-// On many platforms it just jumps to sigpanic.
-func sigpanic0()
-
-// intArgRegs is used by the various register assignment
-// algorithm implementations in the runtime. These include:.
-// - Finalizers (mfinal.go)
-// - Windows callbacks (syscall_windows.go)
-//
-// Both are stripped-down versions of the algorithm since they
-// only have to deal with a subset of cases (finalizers only
-// take a pointer or interface argument, Go Windows callbacks
-// don't support floating point).
-//
-// It should be modified with care and are generally only
-// modified when testing this package.
-//
-// It should never be set higher than its internal/abi
-// constant counterparts, because the system relies on a
-// structure that is at least large enough to hold the
-// registers the system supports.
-//
-// Protected by finlock.
-var intArgRegs = abi.IntArgRegs * (goexperiment.RegabiArgsInt | goarch.IsAmd64)
diff --git a/contrib/go/_std_1.18/src/runtime/stubs2.go b/contrib/go/_std_1.18/src/runtime/stubs2.go
deleted file mode 100644
index 9aa965454d..0000000000
--- a/contrib/go/_std_1.18/src/runtime/stubs2.go
+++ /dev/null
@@ -1,40 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build !aix && !darwin && !js && !openbsd && !plan9 && !solaris && !windows
-
-package runtime
-
-import "unsafe"
-
-// read calls the read system call.
-// It returns a non-negative number of bytes written or a negative errno value.
-func read(fd int32, p unsafe.Pointer, n int32) int32
-
-func closefd(fd int32) int32
-
-func exit(code int32)
-func usleep(usec uint32)
-
-//go:nosplit
-func usleep_no_g(usec uint32) {
-	usleep(usec)
-}
-
-// write calls the write system call.
-// It returns a non-negative number of bytes written or a negative errno value.
-//go:noescape
-func write1(fd uintptr, p unsafe.Pointer, n int32) int32
-
-//go:noescape
-func open(name *byte, mode, perm int32) int32
-
-// return value is only set on linux to be used in osinit()
-func madvise(addr unsafe.Pointer, n uintptr, flags int32) int32
-
-// exitThread terminates the current thread, writing *wait = 0 when
-// the stack is safe to reclaim.
-//
-//go:noescape
-func exitThread(wait *uint32)
diff --git a/contrib/go/_std_1.18/src/runtime/stubs_linux.go b/contrib/go/_std_1.18/src/runtime/stubs_linux.go
deleted file mode 100644
index 06c14e2160..0000000000
--- a/contrib/go/_std_1.18/src/runtime/stubs_linux.go
+++ /dev/null
@@ -1,19 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build linux
-
-package runtime
-
-import "unsafe"
-
-func sbrk0() uintptr
-
-// Called from write_err_android.go only, but defined in sys_linux_*.s;
-// declared here (instead of in write_err_android.go) for go vet on non-android builds.
-// The return value is the raw syscall result, which may encode an error number.
-//go:noescape
-func access(name *byte, mode int32) int32
-func connect(fd int32, addr unsafe.Pointer, len int32) int32
-func socket(domain int32, typ int32, prot int32) int32
diff --git a/contrib/go/_std_1.18/src/runtime/symtab.go b/contrib/go/_std_1.18/src/runtime/symtab.go
deleted file mode 100644
index ee4db47314..0000000000
--- a/contrib/go/_std_1.18/src/runtime/symtab.go
+++ /dev/null
@@ -1,1180 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"internal/goarch"
-	"runtime/internal/atomic"
-	"runtime/internal/sys"
-	"unsafe"
-)
-
-// Frames may be used to get function/file/line information for a
-// slice of PC values returned by Callers.
-type Frames struct {
-	// callers is a slice of PCs that have not yet been expanded to frames.
-	callers []uintptr
-
-	// frames is a slice of Frames that have yet to be returned.
-	frames     []Frame
-	frameStore [2]Frame
-}
-
-// Frame is the information returned by Frames for each call frame.
-type Frame struct {
-	// PC is the program counter for the location in this frame.
-	// For a frame that calls another frame, this will be the
-	// program counter of a call instruction. Because of inlining,
-	// multiple frames may have the same PC value, but different
-	// symbolic information.
-	PC uintptr
-
-	// Func is the Func value of this call frame. This may be nil
-	// for non-Go code or fully inlined functions.
-	Func *Func
-
-	// Function is the package path-qualified function name of
-	// this call frame. If non-empty, this string uniquely
-	// identifies a single function in the program.
-	// This may be the empty string if not known.
-	// If Func is not nil then Function == Func.Name().
-	Function string
-
-	// File and Line are the file name and line number of the
-	// location in this frame. For non-leaf frames, this will be
-	// the location of a call. These may be the empty string and
-	// zero, respectively, if not known.
-	File string
-	Line int
-
-	// Entry point program counter for the function; may be zero
-	// if not known. If Func is not nil then Entry ==
-	// Func.Entry().
-	Entry uintptr
-
-	// The runtime's internal view of the function. This field
-	// is set (funcInfo.valid() returns true) only for Go functions,
-	// not for C functions.
-	funcInfo funcInfo
-}
-
-// CallersFrames takes a slice of PC values returned by Callers and
-// prepares to return function/file/line information.
-// Do not change the slice until you are done with the Frames.
-func CallersFrames(callers []uintptr) *Frames {
-	f := &Frames{callers: callers}
-	f.frames = f.frameStore[:0]
-	return f
-}
-
-// Next returns a Frame representing the next call frame in the slice
-// of PC values. If it has already returned all call frames, Next
-// returns a zero Frame.
-//
-// The more result indicates whether the next call to Next will return
-// a valid Frame. It does not necessarily indicate whether this call
-// returned one.
-//
-// See the Frames example for idiomatic usage.
-func (ci *Frames) Next() (frame Frame, more bool) {
-	for len(ci.frames) < 2 {
-		// Find the next frame.
-		// We need to look for 2 frames so we know what
-		// to return for the "more" result.
-		if len(ci.callers) == 0 {
-			break
-		}
-		pc := ci.callers[0]
-		ci.callers = ci.callers[1:]
-		funcInfo := findfunc(pc)
-		if !funcInfo.valid() {
-			if cgoSymbolizer != nil {
-				// Pre-expand cgo frames. We could do this
-				// incrementally, too, but there's no way to
-				// avoid allocation in this case anyway.
-				ci.frames = append(ci.frames, expandCgoFrames(pc)...)
-			}
-			continue
-		}
-		f := funcInfo._Func()
-		entry := f.Entry()
-		if pc > entry {
-			// We store the pc of the start of the instruction following
-			// the instruction in question (the call or the inline mark).
-			// This is done for historical reasons, and to make FuncForPC
-			// work correctly for entries in the result of runtime.Callers.
-			pc--
-		}
-		name := funcname(funcInfo)
-		if inldata := funcdata(funcInfo, _FUNCDATA_InlTree); inldata != nil {
-			inltree := (*[1 << 20]inlinedCall)(inldata)
-			// Non-strict as cgoTraceback may have added bogus PCs
-			// with a valid funcInfo but invalid PCDATA.
-			ix := pcdatavalue1(funcInfo, _PCDATA_InlTreeIndex, pc, nil, false)
-			if ix >= 0 {
-				// Note: entry is not modified. It always refers to a real frame, not an inlined one.
-				f = nil
-				name = funcnameFromNameoff(funcInfo, inltree[ix].func_)
-				// File/line is already correct.
-				// TODO: remove file/line from InlinedCall?
-			}
-		}
-		ci.frames = append(ci.frames, Frame{
-			PC:       pc,
-			Func:     f,
-			Function: name,
-			Entry:    entry,
-			funcInfo: funcInfo,
-			// Note: File,Line set below
-		})
-	}
-
-	// Pop one frame from the frame list. Keep the rest.
-	// Avoid allocation in the common case, which is 1 or 2 frames.
-	switch len(ci.frames) {
-	case 0: // In the rare case when there are no frames at all, we return Frame{}.
-		return
-	case 1:
-		frame = ci.frames[0]
-		ci.frames = ci.frameStore[:0]
-	case 2:
-		frame = ci.frames[0]
-		ci.frameStore[0] = ci.frames[1]
-		ci.frames = ci.frameStore[:1]
-	default:
-		frame = ci.frames[0]
-		ci.frames = ci.frames[1:]
-	}
-	more = len(ci.frames) > 0
-	if frame.funcInfo.valid() {
-		// Compute file/line just before we need to return it,
-		// as it can be expensive. This avoids computing file/line
-		// for the Frame we find but don't return. See issue 32093.
-		file, line := funcline1(frame.funcInfo, frame.PC, false)
-		frame.File, frame.Line = file, int(line)
-	}
-	return
-}
-
-// runtime_expandFinalInlineFrame expands the final pc in stk to include all
-// "callers" if pc is inline.
-//
-//go:linkname runtime_expandFinalInlineFrame runtime/pprof.runtime_expandFinalInlineFrame
-func runtime_expandFinalInlineFrame(stk []uintptr) []uintptr {
-	if len(stk) == 0 {
-		return stk
-	}
-	pc := stk[len(stk)-1]
-	tracepc := pc - 1
-
-	f := findfunc(tracepc)
-	if !f.valid() {
-		// Not a Go function.
-		return stk
-	}
-
-	inldata := funcdata(f, _FUNCDATA_InlTree)
-	if inldata == nil {
-		// Nothing inline in f.
-		return stk
-	}
-
-	// Treat the previous func as normal. We haven't actually checked, but
-	// since this pc was included in the stack, we know it shouldn't be
-	// elided.
-	lastFuncID := funcID_normal
-
-	// Remove pc from stk; we'll re-add it below.
-	stk = stk[:len(stk)-1]
-
-	// See inline expansion in gentraceback.
-	var cache pcvalueCache
-	inltree := (*[1 << 20]inlinedCall)(inldata)
-	for {
-		// Non-strict as cgoTraceback may have added bogus PCs
-		// with a valid funcInfo but invalid PCDATA.
-		ix := pcdatavalue1(f, _PCDATA_InlTreeIndex, tracepc, &cache, false)
-		if ix < 0 {
-			break
-		}
-		if inltree[ix].funcID == funcID_wrapper && elideWrapperCalling(lastFuncID) {
-			// ignore wrappers
-		} else {
-			stk = append(stk, pc)
-		}
-		lastFuncID = inltree[ix].funcID
-		// Back up to an instruction in the "caller".
-		tracepc = f.entry() + uintptr(inltree[ix].parentPc)
-		pc = tracepc + 1
-	}
-
-	// N.B. we want to keep the last parentPC which is not inline.
-	stk = append(stk, pc)
-
-	return stk
-}
-
-// expandCgoFrames expands frame information for pc, known to be
-// a non-Go function, using the cgoSymbolizer hook. expandCgoFrames
-// returns nil if pc could not be expanded.
-func expandCgoFrames(pc uintptr) []Frame {
-	arg := cgoSymbolizerArg{pc: pc}
-	callCgoSymbolizer(&arg)
-
-	if arg.file == nil && arg.funcName == nil {
-		// No useful information from symbolizer.
-		return nil
-	}
-
-	var frames []Frame
-	for {
-		frames = append(frames, Frame{
-			PC:       pc,
-			Func:     nil,
-			Function: gostring(arg.funcName),
-			File:     gostring(arg.file),
-			Line:     int(arg.lineno),
-			Entry:    arg.entry,
-			// funcInfo is zero, which implies !funcInfo.valid().
-			// That ensures that we use the File/Line info given here.
-		})
-		if arg.more == 0 {
-			break
-		}
-		callCgoSymbolizer(&arg)
-	}
-
-	// No more frames for this PC. Tell the symbolizer we are done.
-	// We don't try to maintain a single cgoSymbolizerArg for the
-	// whole use of Frames, because there would be no good way to tell
-	// the symbolizer when we are done.
-	arg.pc = 0
-	callCgoSymbolizer(&arg)
-
-	return frames
-}
-
-// NOTE: Func does not expose the actual unexported fields, because we return *Func
-// values to users, and we want to keep them from being able to overwrite the data
-// with (say) *f = Func{}.
-// All code operating on a *Func must call raw() to get the *_func
-// or funcInfo() to get the funcInfo instead.
-
-// A Func represents a Go function in the running binary.
-type Func struct {
-	opaque struct{} // unexported field to disallow conversions
-}
-
-func (f *Func) raw() *_func {
-	return (*_func)(unsafe.Pointer(f))
-}
-
-func (f *Func) funcInfo() funcInfo {
-	return f.raw().funcInfo()
-}
-
-func (f *_func) funcInfo() funcInfo {
-	// Find the module containing fn. fn is located in the pclntable.
-	// The unsafe.Pointer to uintptr conversions and arithmetic
-	// are safe because we are working with module addresses.
-	ptr := uintptr(unsafe.Pointer(f))
-	var mod *moduledata
-	for datap := &firstmoduledata; datap != nil; datap = datap.next {
-		if len(datap.pclntable) == 0 {
-			continue
-		}
-		base := uintptr(unsafe.Pointer(&datap.pclntable[0]))
-		if base <= ptr && ptr < base+uintptr(len(datap.pclntable)) {
-			mod = datap
-			break
-		}
-	}
-	return funcInfo{f, mod}
-}
-
-// PCDATA and FUNCDATA table indexes.
-//
-// See funcdata.h and ../cmd/internal/objabi/funcdata.go.
-const (
-	_PCDATA_UnsafePoint   = 0
-	_PCDATA_StackMapIndex = 1
-	_PCDATA_InlTreeIndex  = 2
-	_PCDATA_ArgLiveIndex  = 3
-
-	_FUNCDATA_ArgsPointerMaps    = 0
-	_FUNCDATA_LocalsPointerMaps  = 1
-	_FUNCDATA_StackObjects       = 2
-	_FUNCDATA_InlTree            = 3
-	_FUNCDATA_OpenCodedDeferInfo = 4
-	_FUNCDATA_ArgInfo            = 5
-	_FUNCDATA_ArgLiveInfo        = 6
-	_FUNCDATA_WrapInfo           = 7
-
-	_ArgsSizeUnknown = -0x80000000
-)
-
-const (
-	// PCDATA_UnsafePoint values.
-	_PCDATA_UnsafePointSafe   = -1 // Safe for async preemption
-	_PCDATA_UnsafePointUnsafe = -2 // Unsafe for async preemption
-
-	// _PCDATA_Restart1(2) apply on a sequence of instructions, within
-	// which if an async preemption happens, we should back off the PC
-	// to the start of the sequence when resume.
-	// We need two so we can distinguish the start/end of the sequence
-	// in case that two sequences are next to each other.
-	_PCDATA_Restart1 = -3
-	_PCDATA_Restart2 = -4
-
-	// Like _PCDATA_RestartAtEntry, but back to function entry if async
-	// preempted.
-	_PCDATA_RestartAtEntry = -5
-)
-
-// A FuncID identifies particular functions that need to be treated
-// specially by the runtime.
-// Note that in some situations involving plugins, there may be multiple
-// copies of a particular special runtime function.
-// Note: this list must match the list in cmd/internal/objabi/funcid.go.
-type funcID uint8
-
-const (
-	funcID_normal funcID = iota // not a special function
-	funcID_abort
-	funcID_asmcgocall
-	funcID_asyncPreempt
-	funcID_cgocallback
-	funcID_debugCallV2
-	funcID_gcBgMarkWorker
-	funcID_goexit
-	funcID_gogo
-	funcID_gopanic
-	funcID_handleAsyncEvent
-	funcID_mcall
-	funcID_morestack
-	funcID_mstart
-	funcID_panicwrap
-	funcID_rt0_go
-	funcID_runfinq
-	funcID_runtime_main
-	funcID_sigpanic
-	funcID_systemstack
-	funcID_systemstack_switch
-	funcID_wrapper // any autogenerated code (hash/eq algorithms, method wrappers, etc.)
-)
-
-// A FuncFlag holds bits about a function.
-// This list must match the list in cmd/internal/objabi/funcid.go.
-type funcFlag uint8
-
-const (
-	// TOPFRAME indicates a function that appears at the top of its stack.
-	// The traceback routine stop at such a function and consider that a
-	// successful, complete traversal of the stack.
-	// Examples of TOPFRAME functions include goexit, which appears
-	// at the top of a user goroutine stack, and mstart, which appears
-	// at the top of a system goroutine stack.
-	funcFlag_TOPFRAME funcFlag = 1 << iota
-
-	// SPWRITE indicates a function that writes an arbitrary value to SP
-	// (any write other than adding or subtracting a constant amount).
-	// The traceback routines cannot encode such changes into the
-	// pcsp tables, so the function traceback cannot safely unwind past
-	// SPWRITE functions. Stopping at an SPWRITE function is considered
-	// to be an incomplete unwinding of the stack. In certain contexts
-	// (in particular garbage collector stack scans) that is a fatal error.
-	funcFlag_SPWRITE
-
-	// ASM indicates that a function was implemented in assembly.
-	funcFlag_ASM
-)
-
-// pcHeader holds data used by the pclntab lookups.
-type pcHeader struct {
-	magic          uint32  // 0xFFFFFFF0
-	pad1, pad2     uint8   // 0,0
-	minLC          uint8   // min instruction size
-	ptrSize        uint8   // size of a ptr in bytes
-	nfunc          int     // number of functions in the module
-	nfiles         uint    // number of entries in the file tab
-	textStart      uintptr // base for function entry PC offsets in this module, equal to moduledata.text
-	funcnameOffset uintptr // offset to the funcnametab variable from pcHeader
-	cuOffset       uintptr // offset to the cutab variable from pcHeader
-	filetabOffset  uintptr // offset to the filetab variable from pcHeader
-	pctabOffset    uintptr // offset to the pctab variable from pcHeader
-	pclnOffset     uintptr // offset to the pclntab variable from pcHeader
-}
-
-// moduledata records information about the layout of the executable
-// image. It is written by the linker. Any changes here must be
-// matched changes to the code in cmd/link/internal/ld/symtab.go:symtab.
-// moduledata is stored in statically allocated non-pointer memory;
-// none of the pointers here are visible to the garbage collector.
-type moduledata struct {
-	pcHeader     *pcHeader
-	funcnametab  []byte
-	cutab        []uint32
-	filetab      []byte
-	pctab        []byte
-	pclntable    []byte
-	ftab         []functab
-	findfunctab  uintptr
-	minpc, maxpc uintptr
-
-	text, etext           uintptr
-	noptrdata, enoptrdata uintptr
-	data, edata           uintptr
-	bss, ebss             uintptr
-	noptrbss, enoptrbss   uintptr
-	end, gcdata, gcbss    uintptr
-	types, etypes         uintptr
-	rodata                uintptr
-	gofunc                uintptr // go.func.*
-
-	textsectmap []textsect
-	typelinks   []int32 // offsets from types
-	itablinks   []*itab
-
-	ptab []ptabEntry
-
-	pluginpath string
-	pkghashes  []modulehash
-
-	modulename   string
-	modulehashes []modulehash
-
-	hasmain uint8 // 1 if module contains the main function, 0 otherwise
-
-	gcdatamask, gcbssmask bitvector
-
-	typemap map[typeOff]*_type // offset to *_rtype in previous module
-
-	bad bool // module failed to load and should be ignored
-
-	next *moduledata
-}
-
-// A modulehash is used to compare the ABI of a new module or a
-// package in a new module with the loaded program.
-//
-// For each shared library a module links against, the linker creates an entry in the
-// moduledata.modulehashes slice containing the name of the module, the abi hash seen
-// at link time and a pointer to the runtime abi hash. These are checked in
-// moduledataverify1 below.
-//
-// For each loaded plugin, the pkghashes slice has a modulehash of the
-// newly loaded package that can be used to check the plugin's version of
-// a package against any previously loaded version of the package.
-// This is done in plugin.lastmoduleinit.
-type modulehash struct {
-	modulename   string
-	linktimehash string
-	runtimehash  *string
-}
-
-// pinnedTypemaps are the map[typeOff]*_type from the moduledata objects.
-//
-// These typemap objects are allocated at run time on the heap, but the
-// only direct reference to them is in the moduledata, created by the
-// linker and marked SNOPTRDATA so it is ignored by the GC.
-//
-// To make sure the map isn't collected, we keep a second reference here.
-var pinnedTypemaps []map[typeOff]*_type
-
-var firstmoduledata moduledata  // linker symbol
-var lastmoduledatap *moduledata // linker symbol
-var modulesSlice *[]*moduledata // see activeModules
-
-// activeModules returns a slice of active modules.
-//
-// A module is active once its gcdatamask and gcbssmask have been
-// assembled and it is usable by the GC.
-//
-// This is nosplit/nowritebarrier because it is called by the
-// cgo pointer checking code.
-//go:nosplit
-//go:nowritebarrier
-func activeModules() []*moduledata {
-	p := (*[]*moduledata)(atomic.Loadp(unsafe.Pointer(&modulesSlice)))
-	if p == nil {
-		return nil
-	}
-	return *p
-}
-
-// modulesinit creates the active modules slice out of all loaded modules.
-//
-// When a module is first loaded by the dynamic linker, an .init_array
-// function (written by cmd/link) is invoked to call addmoduledata,
-// appending to the module to the linked list that starts with
-// firstmoduledata.
-//
-// There are two times this can happen in the lifecycle of a Go
-// program. First, if compiled with -linkshared, a number of modules
-// built with -buildmode=shared can be loaded at program initialization.
-// Second, a Go program can load a module while running that was built
-// with -buildmode=plugin.
-//
-// After loading, this function is called which initializes the
-// moduledata so it is usable by the GC and creates a new activeModules
-// list.
-//
-// Only one goroutine may call modulesinit at a time.
-func modulesinit() {
-	modules := new([]*moduledata)
-	for md := &firstmoduledata; md != nil; md = md.next {
-		if md.bad {
-			continue
-		}
-		*modules = append(*modules, md)
-		if md.gcdatamask == (bitvector{}) {
-			scanDataSize := md.edata - md.data
-			md.gcdatamask = progToPointerMask((*byte)(unsafe.Pointer(md.gcdata)), scanDataSize)
-			scanBSSSize := md.ebss - md.bss
-			md.gcbssmask = progToPointerMask((*byte)(unsafe.Pointer(md.gcbss)), scanBSSSize)
-			gcController.addGlobals(int64(scanDataSize + scanBSSSize))
-		}
-	}
-
-	// Modules appear in the moduledata linked list in the order they are
-	// loaded by the dynamic loader, with one exception: the
-	// firstmoduledata itself the module that contains the runtime. This
-	// is not always the first module (when using -buildmode=shared, it
-	// is typically libstd.so, the second module). The order matters for
-	// typelinksinit, so we swap the first module with whatever module
-	// contains the main function.
-	//
-	// See Issue #18729.
-	for i, md := range *modules {
-		if md.hasmain != 0 {
-			(*modules)[0] = md
-			(*modules)[i] = &firstmoduledata
-			break
-		}
-	}
-
-	atomicstorep(unsafe.Pointer(&modulesSlice), unsafe.Pointer(modules))
-}
-
-type functab struct {
-	entryoff uint32 // relative to runtime.text
-	funcoff  uint32
-}
-
-// Mapping information for secondary text sections
-
-type textsect struct {
-	vaddr    uintptr // prelinked section vaddr
-	end      uintptr // vaddr + section length
-	baseaddr uintptr // relocated section address
-}
-
-const minfunc = 16                 // minimum function size
-const pcbucketsize = 256 * minfunc // size of bucket in the pc->func lookup table
-
-// findfunctab is an array of these structures.
-// Each bucket represents 4096 bytes of the text segment.
-// Each subbucket represents 256 bytes of the text segment.
-// To find a function given a pc, locate the bucket and subbucket for
-// that pc. Add together the idx and subbucket value to obtain a
-// function index. Then scan the functab array starting at that
-// index to find the target function.
-// This table uses 20 bytes for every 4096 bytes of code, or ~0.5% overhead.
-type findfuncbucket struct {
-	idx        uint32
-	subbuckets [16]byte
-}
-
-func moduledataverify() {
-	for datap := &firstmoduledata; datap != nil; datap = datap.next {
-		moduledataverify1(datap)
-	}
-}
-
-const debugPcln = false
-
-func moduledataverify1(datap *moduledata) {
-	// Check that the pclntab's format is valid.
-	hdr := datap.pcHeader
-	if hdr.magic != 0xfffffff0 || hdr.pad1 != 0 || hdr.pad2 != 0 ||
-		hdr.minLC != sys.PCQuantum || hdr.ptrSize != goarch.PtrSize || hdr.textStart != datap.text {
-		println("runtime: pcHeader: magic=", hex(hdr.magic), "pad1=", hdr.pad1, "pad2=", hdr.pad2,
-			"minLC=", hdr.minLC, "ptrSize=", hdr.ptrSize, "pcHeader.textStart=", hex(hdr.textStart),
-			"text=", hex(datap.text), "pluginpath=", datap.pluginpath)
-		throw("invalid function symbol table")
-	}
-
-	// ftab is lookup table for function by program counter.
-	nftab := len(datap.ftab) - 1
-	for i := 0; i < nftab; i++ {
-		// NOTE: ftab[nftab].entry is legal; it is the address beyond the final function.
-		if datap.ftab[i].entryoff > datap.ftab[i+1].entryoff {
-			f1 := funcInfo{(*_func)(unsafe.Pointer(&datap.pclntable[datap.ftab[i].funcoff])), datap}
-			f2 := funcInfo{(*_func)(unsafe.Pointer(&datap.pclntable[datap.ftab[i+1].funcoff])), datap}
-			f2name := "end"
-			if i+1 < nftab {
-				f2name = funcname(f2)
-			}
-			println("function symbol table not sorted by PC offset:", hex(datap.ftab[i].entryoff), funcname(f1), ">", hex(datap.ftab[i+1].entryoff), f2name, ", plugin:", datap.pluginpath)
-			for j := 0; j <= i; j++ {
-				println("\t", hex(datap.ftab[j].entryoff), funcname(funcInfo{(*_func)(unsafe.Pointer(&datap.pclntable[datap.ftab[j].funcoff])), datap}))
-			}
-			if GOOS == "aix" && isarchive {
-				println("-Wl,-bnoobjreorder is mandatory on aix/ppc64 with c-archive")
-			}
-			throw("invalid runtime symbol table")
-		}
-	}
-
-	min := datap.textAddr(datap.ftab[0].entryoff)
-	max := datap.textAddr(datap.ftab[nftab].entryoff)
-	if datap.minpc != min || datap.maxpc != max {
-		println("minpc=", hex(datap.minpc), "min=", hex(min), "maxpc=", hex(datap.maxpc), "max=", hex(max))
-		throw("minpc or maxpc invalid")
-	}
-
-	for _, modulehash := range datap.modulehashes {
-		if modulehash.linktimehash != *modulehash.runtimehash {
-			println("abi mismatch detected between", datap.modulename, "and", modulehash.modulename)
-			throw("abi mismatch")
-		}
-	}
-}
-
-// textAddr returns md.text + off, with special handling for multiple text sections.
-// off is a (virtual) offset computed at internal linking time,
-// before the external linker adjusts the sections' base addresses.
-//
-// The text, or instruction stream is generated as one large buffer.
-// The off (offset) for a function is its offset within this buffer.
-// If the total text size gets too large, there can be issues on platforms like ppc64
-// if the target of calls are too far for the call instruction.
-// To resolve the large text issue, the text is split into multiple text sections
-// to allow the linker to generate long calls when necessary.
-// When this happens, the vaddr for each text section is set to its offset within the text.
-// Each function's offset is compared against the section vaddrs and ends to determine the containing section.
-// Then the section relative offset is added to the section's
-// relocated baseaddr to compute the function address.
-//
-// It is nosplit because it is part of the findfunc implementation.
-//go:nosplit
-func (md *moduledata) textAddr(off32 uint32) uintptr {
-	off := uintptr(off32)
-	res := md.text + off
-	if len(md.textsectmap) > 1 {
-		for i, sect := range md.textsectmap {
-			// For the last section, include the end address (etext), as it is included in the functab.
-			if off >= sect.vaddr && off < sect.end || (i == len(md.textsectmap)-1 && off == sect.end) {
-				res = sect.baseaddr + off - sect.vaddr
-				break
-			}
-		}
-		if res > md.etext && GOARCH != "wasm" { // on wasm, functions do not live in the same address space as the linear memory
-			println("runtime: textAddr", hex(res), "out of range", hex(md.text), "-", hex(md.etext))
-			throw("runtime: text offset out of range")
-		}
-	}
-	return res
-}
-
-// textOff is the opposite of textAddr. It converts a PC to a (virtual) offset
-// to md.text, and returns if the PC is in any Go text section.
-//
-// It is nosplit because it is part of the findfunc implementation.
-//go:nosplit
-func (md *moduledata) textOff(pc uintptr) (uint32, bool) {
-	res := uint32(pc - md.text)
-	if len(md.textsectmap) > 1 {
-		for i, sect := range md.textsectmap {
-			if sect.baseaddr > pc {
-				// pc is not in any section.
-				return 0, false
-			}
-			end := sect.baseaddr + (sect.end - sect.vaddr)
-			// For the last section, include the end address (etext), as it is included in the functab.
-			if i == len(md.textsectmap) {
-				end++
-			}
-			if pc < end {
-				res = uint32(pc - sect.baseaddr + sect.vaddr)
-				break
-			}
-		}
-	}
-	return res, true
-}
-
-// FuncForPC returns a *Func describing the function that contains the
-// given program counter address, or else nil.
-//
-// If pc represents multiple functions because of inlining, it returns
-// the *Func describing the innermost function, but with an entry of
-// the outermost function.
-func FuncForPC(pc uintptr) *Func {
-	f := findfunc(pc)
-	if !f.valid() {
-		return nil
-	}
-	if inldata := funcdata(f, _FUNCDATA_InlTree); inldata != nil {
-		// Note: strict=false so bad PCs (those between functions) don't crash the runtime.
-		// We just report the preceding function in that situation. See issue 29735.
-		// TODO: Perhaps we should report no function at all in that case.
-		// The runtime currently doesn't have function end info, alas.
-		if ix := pcdatavalue1(f, _PCDATA_InlTreeIndex, pc, nil, false); ix >= 0 {
-			inltree := (*[1 << 20]inlinedCall)(inldata)
-			name := funcnameFromNameoff(f, inltree[ix].func_)
-			file, line := funcline(f, pc)
-			fi := &funcinl{
-				ones:  ^uint32(0),
-				entry: f.entry(), // entry of the real (the outermost) function.
-				name:  name,
-				file:  file,
-				line:  int(line),
-			}
-			return (*Func)(unsafe.Pointer(fi))
-		}
-	}
-	return f._Func()
-}
-
-// Name returns the name of the function.
-func (f *Func) Name() string {
-	if f == nil {
-		return ""
-	}
-	fn := f.raw()
-	if fn.isInlined() { // inlined version
-		fi := (*funcinl)(unsafe.Pointer(fn))
-		return fi.name
-	}
-	return funcname(f.funcInfo())
-}
-
-// Entry returns the entry address of the function.
-func (f *Func) Entry() uintptr {
-	fn := f.raw()
-	if fn.isInlined() { // inlined version
-		fi := (*funcinl)(unsafe.Pointer(fn))
-		return fi.entry
-	}
-	return fn.funcInfo().entry()
-}
-
-// FileLine returns the file name and line number of the
-// source code corresponding to the program counter pc.
-// The result will not be accurate if pc is not a program
-// counter within f.
-func (f *Func) FileLine(pc uintptr) (file string, line int) {
-	fn := f.raw()
-	if fn.isInlined() { // inlined version
-		fi := (*funcinl)(unsafe.Pointer(fn))
-		return fi.file, fi.line
-	}
-	// Pass strict=false here, because anyone can call this function,
-	// and they might just be wrong about targetpc belonging to f.
-	file, line32 := funcline1(f.funcInfo(), pc, false)
-	return file, int(line32)
-}
-
-// findmoduledatap looks up the moduledata for a PC.
-//
-// It is nosplit because it's part of the isgoexception
-// implementation.
-//
-//go:nosplit
-func findmoduledatap(pc uintptr) *moduledata {
-	for datap := &firstmoduledata; datap != nil; datap = datap.next {
-		if datap.minpc <= pc && pc < datap.maxpc {
-			return datap
-		}
-	}
-	return nil
-}
-
-type funcInfo struct {
-	*_func
-	datap *moduledata
-}
-
-func (f funcInfo) valid() bool {
-	return f._func != nil
-}
-
-func (f funcInfo) _Func() *Func {
-	return (*Func)(unsafe.Pointer(f._func))
-}
-
-// isInlined reports whether f should be re-interpreted as a *funcinl.
-func (f *_func) isInlined() bool {
-	return f.entryoff == ^uint32(0) // see comment for funcinl.ones
-}
-
-// entry returns the entry PC for f.
-func (f funcInfo) entry() uintptr {
-	return f.datap.textAddr(f.entryoff)
-}
-
-// findfunc looks up function metadata for a PC.
-//
-// It is nosplit because it's part of the isgoexception
-// implementation.
-//
-//go:nosplit
-func findfunc(pc uintptr) funcInfo {
-	datap := findmoduledatap(pc)
-	if datap == nil {
-		return funcInfo{}
-	}
-	const nsub = uintptr(len(findfuncbucket{}.subbuckets))
-
-	pcOff, ok := datap.textOff(pc)
-	if !ok {
-		return funcInfo{}
-	}
-
-	x := uintptr(pcOff) + datap.text - datap.minpc // TODO: are datap.text and datap.minpc always equal?
-	b := x / pcbucketsize
-	i := x % pcbucketsize / (pcbucketsize / nsub)
-
-	ffb := (*findfuncbucket)(add(unsafe.Pointer(datap.findfunctab), b*unsafe.Sizeof(findfuncbucket{})))
-	idx := ffb.idx + uint32(ffb.subbuckets[i])
-
-	// Find the ftab entry.
-	for datap.ftab[idx+1].entryoff <= pcOff {
-		idx++
-	}
-
-	funcoff := datap.ftab[idx].funcoff
-	return funcInfo{(*_func)(unsafe.Pointer(&datap.pclntable[funcoff])), datap}
-}
-
-type pcvalueCache struct {
-	entries [2][8]pcvalueCacheEnt
-}
-
-type pcvalueCacheEnt struct {
-	// targetpc and off together are the key of this cache entry.
-	targetpc uintptr
-	off      uint32
-	// val is the value of this cached pcvalue entry.
-	val int32
-}
-
-// pcvalueCacheKey returns the outermost index in a pcvalueCache to use for targetpc.
-// It must be very cheap to calculate.
-// For now, align to goarch.PtrSize and reduce mod the number of entries.
-// In practice, this appears to be fairly randomly and evenly distributed.
-func pcvalueCacheKey(targetpc uintptr) uintptr {
-	return (targetpc / goarch.PtrSize) % uintptr(len(pcvalueCache{}.entries))
-}
-
-// Returns the PCData value, and the PC where this value starts.
-// TODO: the start PC is returned only when cache is nil.
-func pcvalue(f funcInfo, off uint32, targetpc uintptr, cache *pcvalueCache, strict bool) (int32, uintptr) {
-	if off == 0 {
-		return -1, 0
-	}
-
-	// Check the cache. This speeds up walks of deep stacks, which
-	// tend to have the same recursive functions over and over.
-	//
-	// This cache is small enough that full associativity is
-	// cheaper than doing the hashing for a less associative
-	// cache.
-	if cache != nil {
-		x := pcvalueCacheKey(targetpc)
-		for i := range cache.entries[x] {
-			// We check off first because we're more
-			// likely to have multiple entries with
-			// different offsets for the same targetpc
-			// than the other way around, so we'll usually
-			// fail in the first clause.
-			ent := &cache.entries[x][i]
-			if ent.off == off && ent.targetpc == targetpc {
-				return ent.val, 0
-			}
-		}
-	}
-
-	if !f.valid() {
-		if strict && panicking == 0 {
-			println("runtime: no module data for", hex(f.entry()))
-			throw("no module data")
-		}
-		return -1, 0
-	}
-	datap := f.datap
-	p := datap.pctab[off:]
-	pc := f.entry()
-	prevpc := pc
-	val := int32(-1)
-	for {
-		var ok bool
-		p, ok = step(p, &pc, &val, pc == f.entry())
-		if !ok {
-			break
-		}
-		if targetpc < pc {
-			// Replace a random entry in the cache. Random
-			// replacement prevents a performance cliff if
-			// a recursive stack's cycle is slightly
-			// larger than the cache.
-			// Put the new element at the beginning,
-			// since it is the most likely to be newly used.
-			if cache != nil {
-				x := pcvalueCacheKey(targetpc)
-				e := &cache.entries[x]
-				ci := fastrandn(uint32(len(cache.entries[x])))
-				e[ci] = e[0]
-				e[0] = pcvalueCacheEnt{
-					targetpc: targetpc,
-					off:      off,
-					val:      val,
-				}
-			}
-
-			return val, prevpc
-		}
-		prevpc = pc
-	}
-
-	// If there was a table, it should have covered all program counters.
-	// If not, something is wrong.
-	if panicking != 0 || !strict {
-		return -1, 0
-	}
-
-	print("runtime: invalid pc-encoded table f=", funcname(f), " pc=", hex(pc), " targetpc=", hex(targetpc), " tab=", p, "\n")
-
-	p = datap.pctab[off:]
-	pc = f.entry()
-	val = -1
-	for {
-		var ok bool
-		p, ok = step(p, &pc, &val, pc == f.entry())
-		if !ok {
-			break
-		}
-		print("\tvalue=", val, " until pc=", hex(pc), "\n")
-	}
-
-	throw("invalid runtime symbol table")
-	return -1, 0
-}
-
-func cfuncname(f funcInfo) *byte {
-	if !f.valid() || f.nameoff == 0 {
-		return nil
-	}
-	return &f.datap.funcnametab[f.nameoff]
-}
-
-func funcname(f funcInfo) string {
-	return gostringnocopy(cfuncname(f))
-}
-
-func funcpkgpath(f funcInfo) string {
-	name := funcname(f)
-	i := len(name) - 1
-	for ; i > 0; i-- {
-		if name[i] == '/' {
-			break
-		}
-	}
-	for ; i < len(name); i++ {
-		if name[i] == '.' {
-			break
-		}
-	}
-	return name[:i]
-}
-
-func cfuncnameFromNameoff(f funcInfo, nameoff int32) *byte {
-	if !f.valid() {
-		return nil
-	}
-	return &f.datap.funcnametab[nameoff]
-}
-
-func funcnameFromNameoff(f funcInfo, nameoff int32) string {
-	return gostringnocopy(cfuncnameFromNameoff(f, nameoff))
-}
-
-func funcfile(f funcInfo, fileno int32) string {
-	datap := f.datap
-	if !f.valid() {
-		return "?"
-	}
-	// Make sure the cu index and file offset are valid
-	if fileoff := datap.cutab[f.cuOffset+uint32(fileno)]; fileoff != ^uint32(0) {
-		return gostringnocopy(&datap.filetab[fileoff])
-	}
-	// pcln section is corrupt.
-	return "?"
-}
-
-func funcline1(f funcInfo, targetpc uintptr, strict bool) (file string, line int32) {
-	datap := f.datap
-	if !f.valid() {
-		return "?", 0
-	}
-	fileno, _ := pcvalue(f, f.pcfile, targetpc, nil, strict)
-	line, _ = pcvalue(f, f.pcln, targetpc, nil, strict)
-	if fileno == -1 || line == -1 || int(fileno) >= len(datap.filetab) {
-		// print("looking for ", hex(targetpc), " in ", funcname(f), " got file=", fileno, " line=", lineno, "\n")
-		return "?", 0
-	}
-	file = funcfile(f, fileno)
-	return
-}
-
-func funcline(f funcInfo, targetpc uintptr) (file string, line int32) {
-	return funcline1(f, targetpc, true)
-}
-
-func funcspdelta(f funcInfo, targetpc uintptr, cache *pcvalueCache) int32 {
-	x, _ := pcvalue(f, f.pcsp, targetpc, cache, true)
-	if debugPcln && x&(goarch.PtrSize-1) != 0 {
-		print("invalid spdelta ", funcname(f), " ", hex(f.entry()), " ", hex(targetpc), " ", hex(f.pcsp), " ", x, "\n")
-		throw("bad spdelta")
-	}
-	return x
-}
-
-// funcMaxSPDelta returns the maximum spdelta at any point in f.
-func funcMaxSPDelta(f funcInfo) int32 {
-	datap := f.datap
-	p := datap.pctab[f.pcsp:]
-	pc := f.entry()
-	val := int32(-1)
-	max := int32(0)
-	for {
-		var ok bool
-		p, ok = step(p, &pc, &val, pc == f.entry())
-		if !ok {
-			return max
-		}
-		if val > max {
-			max = val
-		}
-	}
-}
-
-func pcdatastart(f funcInfo, table uint32) uint32 {
-	return *(*uint32)(add(unsafe.Pointer(&f.nfuncdata), unsafe.Sizeof(f.nfuncdata)+uintptr(table)*4))
-}
-
-func pcdatavalue(f funcInfo, table uint32, targetpc uintptr, cache *pcvalueCache) int32 {
-	if table >= f.npcdata {
-		return -1
-	}
-	r, _ := pcvalue(f, pcdatastart(f, table), targetpc, cache, true)
-	return r
-}
-
-func pcdatavalue1(f funcInfo, table uint32, targetpc uintptr, cache *pcvalueCache, strict bool) int32 {
-	if table >= f.npcdata {
-		return -1
-	}
-	r, _ := pcvalue(f, pcdatastart(f, table), targetpc, cache, strict)
-	return r
-}
-
-// Like pcdatavalue, but also return the start PC of this PCData value.
-// It doesn't take a cache.
-func pcdatavalue2(f funcInfo, table uint32, targetpc uintptr) (int32, uintptr) {
-	if table >= f.npcdata {
-		return -1, 0
-	}
-	return pcvalue(f, pcdatastart(f, table), targetpc, nil, true)
-}
-
-// funcdata returns a pointer to the ith funcdata for f.
-// funcdata should be kept in sync with cmd/link:writeFuncs.
-func funcdata(f funcInfo, i uint8) unsafe.Pointer {
-	if i < 0 || i >= f.nfuncdata {
-		return nil
-	}
-	base := f.datap.gofunc // load gofunc address early so that we calculate during cache misses
-	p := uintptr(unsafe.Pointer(&f.nfuncdata)) + unsafe.Sizeof(f.nfuncdata) + uintptr(f.npcdata)*4 + uintptr(i)*4
-	off := *(*uint32)(unsafe.Pointer(p))
-	// Return off == ^uint32(0) ? 0 : f.datap.gofunc + uintptr(off), but without branches.
-	// The compiler calculates mask on most architectures using conditional assignment.
-	var mask uintptr
-	if off == ^uint32(0) {
-		mask = 1
-	}
-	mask--
-	raw := base + uintptr(off)
-	return unsafe.Pointer(raw & mask)
-}
-
-// step advances to the next pc, value pair in the encoded table.
-func step(p []byte, pc *uintptr, val *int32, first bool) (newp []byte, ok bool) {
-	// For both uvdelta and pcdelta, the common case (~70%)
-	// is that they are a single byte. If so, avoid calling readvarint.
-	uvdelta := uint32(p[0])
-	if uvdelta == 0 && !first {
-		return nil, false
-	}
-	n := uint32(1)
-	if uvdelta&0x80 != 0 {
-		n, uvdelta = readvarint(p)
-	}
-	*val += int32(-(uvdelta & 1) ^ (uvdelta >> 1))
-	p = p[n:]
-
-	pcdelta := uint32(p[0])
-	n = 1
-	if pcdelta&0x80 != 0 {
-		n, pcdelta = readvarint(p)
-	}
-	p = p[n:]
-	*pc += uintptr(pcdelta * sys.PCQuantum)
-	return p, true
-}
-
-// readvarint reads a varint from p.
-func readvarint(p []byte) (read uint32, val uint32) {
-	var v, shift, n uint32
-	for {
-		b := p[n]
-		n++
-		v |= uint32(b&0x7F) << (shift & 31)
-		if b&0x80 == 0 {
-			break
-		}
-		shift += 7
-	}
-	return n, v
-}
-
-type stackmap struct {
-	n        int32   // number of bitmaps
-	nbit     int32   // number of bits in each bitmap
-	bytedata [1]byte // bitmaps, each starting on a byte boundary
-}
-
-//go:nowritebarrier
-func stackmapdata(stkmap *stackmap, n int32) bitvector {
-	// Check this invariant only when stackDebug is on at all.
-	// The invariant is already checked by many of stackmapdata's callers,
-	// and disabling it by default allows stackmapdata to be inlined.
-	if stackDebug > 0 && (n < 0 || n >= stkmap.n) {
-		throw("stackmapdata: index out of range")
-	}
-	return bitvector{stkmap.nbit, addb(&stkmap.bytedata[0], uintptr(n*((stkmap.nbit+7)>>3)))}
-}
-
-// inlinedCall is the encoding of entries in the FUNCDATA_InlTree table.
-type inlinedCall struct {
-	parent   int16  // index of parent in the inltree, or < 0
-	funcID   funcID // type of the called function
-	_        byte
-	file     int32 // perCU file index for inlined call. See cmd/link:pcln.go
-	line     int32 // line number of the call site
-	func_    int32 // offset into pclntab for name of called function
-	parentPc int32 // position of an instruction whose source position is the call site (offset from entry)
-}
diff --git a/contrib/go/_std_1.18/src/runtime/sys_darwin.go b/contrib/go/_std_1.18/src/runtime/sys_darwin.go
deleted file mode 100644
index 58b3a9171c..0000000000
--- a/contrib/go/_std_1.18/src/runtime/sys_darwin.go
+++ /dev/null
@@ -1,536 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"internal/abi"
-	"unsafe"
-)
-
-// The X versions of syscall expect the libc call to return a 64-bit result.
-// Otherwise (the non-X version) expects a 32-bit result.
-// This distinction is required because an error is indicated by returning -1,
-// and we need to know whether to check 32 or 64 bits of the result.
-// (Some libc functions that return 32 bits put junk in the upper 32 bits of AX.)
-
-//go:linkname syscall_syscall syscall.syscall
-//go:nosplit
-func syscall_syscall(fn, a1, a2, a3 uintptr) (r1, r2, err uintptr) {
-	args := struct{ fn, a1, a2, a3, r1, r2, err uintptr }{fn, a1, a2, a3, r1, r2, err}
-	entersyscall()
-	libcCall(unsafe.Pointer(abi.FuncPCABI0(syscall)), unsafe.Pointer(&args))
-	exitsyscall()
-	return args.r1, args.r2, args.err
-}
-func syscall()
-
-//go:linkname syscall_syscallX syscall.syscallX
-//go:nosplit
-func syscall_syscallX(fn, a1, a2, a3 uintptr) (r1, r2, err uintptr) {
-	args := struct{ fn, a1, a2, a3, r1, r2, err uintptr }{fn, a1, a2, a3, r1, r2, err}
-	entersyscall()
-	libcCall(unsafe.Pointer(abi.FuncPCABI0(syscallX)), unsafe.Pointer(&args))
-	exitsyscall()
-	return args.r1, args.r2, args.err
-}
-func syscallX()
-
-//go:linkname syscall_syscall6 syscall.syscall6
-//go:nosplit
-func syscall_syscall6(fn, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr) {
-	args := struct{ fn, a1, a2, a3, a4, a5, a6, r1, r2, err uintptr }{fn, a1, a2, a3, a4, a5, a6, r1, r2, err}
-	entersyscall()
-	libcCall(unsafe.Pointer(abi.FuncPCABI0(syscall6)), unsafe.Pointer(&args))
-	exitsyscall()
-	return args.r1, args.r2, args.err
-}
-func syscall6()
-
-//go:linkname syscall_syscall6X syscall.syscall6X
-//go:nosplit
-func syscall_syscall6X(fn, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr) {
-	args := struct{ fn, a1, a2, a3, a4, a5, a6, r1, r2, err uintptr }{fn, a1, a2, a3, a4, a5, a6, r1, r2, err}
-	entersyscall()
-	libcCall(unsafe.Pointer(abi.FuncPCABI0(syscall6X)), unsafe.Pointer(&args))
-	exitsyscall()
-	return args.r1, args.r2, args.err
-}
-func syscall6X()
-
-//go:linkname syscall_syscallPtr syscall.syscallPtr
-//go:nosplit
-func syscall_syscallPtr(fn, a1, a2, a3 uintptr) (r1, r2, err uintptr) {
-	args := struct{ fn, a1, a2, a3, r1, r2, err uintptr }{fn, a1, a2, a3, r1, r2, err}
-	entersyscall()
-	libcCall(unsafe.Pointer(abi.FuncPCABI0(syscallPtr)), unsafe.Pointer(&args))
-	exitsyscall()
-	return args.r1, args.r2, args.err
-}
-func syscallPtr()
-
-//go:linkname syscall_rawSyscall syscall.rawSyscall
-//go:nosplit
-func syscall_rawSyscall(fn, a1, a2, a3 uintptr) (r1, r2, err uintptr) {
-	args := struct{ fn, a1, a2, a3, r1, r2, err uintptr }{fn, a1, a2, a3, r1, r2, err}
-	libcCall(unsafe.Pointer(abi.FuncPCABI0(syscall)), unsafe.Pointer(&args))
-	return args.r1, args.r2, args.err
-}
-
-//go:linkname syscall_rawSyscall6 syscall.rawSyscall6
-//go:nosplit
-func syscall_rawSyscall6(fn, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr) {
-	args := struct{ fn, a1, a2, a3, a4, a5, a6, r1, r2, err uintptr }{fn, a1, a2, a3, a4, a5, a6, r1, r2, err}
-	libcCall(unsafe.Pointer(abi.FuncPCABI0(syscall6)), unsafe.Pointer(&args))
-	return args.r1, args.r2, args.err
-}
-
-// syscallNoErr is used in crypto/x509 to call into Security.framework and CF.
-
-//go:linkname crypto_x509_syscall crypto/x509/internal/macos.syscall
-//go:nosplit
-func crypto_x509_syscall(fn, a1, a2, a3, a4, a5 uintptr, f1 float64) (r1 uintptr) {
-	args := struct {
-		fn, a1, a2, a3, a4, a5 uintptr
-		f1                     float64
-		r1                     uintptr
-	}{fn, a1, a2, a3, a4, a5, f1, r1}
-	entersyscall()
-	libcCall(unsafe.Pointer(abi.FuncPCABI0(syscall_x509)), unsafe.Pointer(&args))
-	exitsyscall()
-	return args.r1
-}
-func syscall_x509()
-
-// The *_trampoline functions convert from the Go calling convention to the C calling convention
-// and then call the underlying libc function.  They are defined in sys_darwin_$ARCH.s.
-
-//go:nosplit
-//go:cgo_unsafe_args
-func pthread_attr_init(attr *pthreadattr) int32 {
-	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(pthread_attr_init_trampoline)), unsafe.Pointer(&attr))
-	KeepAlive(attr)
-	return ret
-}
-func pthread_attr_init_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func pthread_attr_getstacksize(attr *pthreadattr, size *uintptr) int32 {
-	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(pthread_attr_getstacksize_trampoline)), unsafe.Pointer(&attr))
-	KeepAlive(attr)
-	KeepAlive(size)
-	return ret
-}
-func pthread_attr_getstacksize_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func pthread_attr_setdetachstate(attr *pthreadattr, state int) int32 {
-	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(pthread_attr_setdetachstate_trampoline)), unsafe.Pointer(&attr))
-	KeepAlive(attr)
-	return ret
-}
-func pthread_attr_setdetachstate_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func pthread_create(attr *pthreadattr, start uintptr, arg unsafe.Pointer) int32 {
-	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(pthread_create_trampoline)), unsafe.Pointer(&attr))
-	KeepAlive(attr)
-	KeepAlive(arg) // Just for consistency. Arg of course needs to be kept alive for the start function.
-	return ret
-}
-func pthread_create_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func raise(sig uint32) {
-	libcCall(unsafe.Pointer(abi.FuncPCABI0(raise_trampoline)), unsafe.Pointer(&sig))
-}
-func raise_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func pthread_self() (t pthread) {
-	libcCall(unsafe.Pointer(abi.FuncPCABI0(pthread_self_trampoline)), unsafe.Pointer(&t))
-	return
-}
-func pthread_self_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func pthread_kill(t pthread, sig uint32) {
-	libcCall(unsafe.Pointer(abi.FuncPCABI0(pthread_kill_trampoline)), unsafe.Pointer(&t))
-	return
-}
-func pthread_kill_trampoline()
-
-// mmap is used to do low-level memory allocation via mmap. Don't allow stack
-// splits, since this function (used by sysAlloc) is called in a lot of low-level
-// parts of the runtime and callers often assume it won't acquire any locks.
-//go:nosplit
-func mmap(addr unsafe.Pointer, n uintptr, prot, flags, fd int32, off uint32) (unsafe.Pointer, int) {
-	args := struct {
-		addr            unsafe.Pointer
-		n               uintptr
-		prot, flags, fd int32
-		off             uint32
-		ret1            unsafe.Pointer
-		ret2            int
-	}{addr, n, prot, flags, fd, off, nil, 0}
-	libcCall(unsafe.Pointer(abi.FuncPCABI0(mmap_trampoline)), unsafe.Pointer(&args))
-	return args.ret1, args.ret2
-}
-func mmap_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func munmap(addr unsafe.Pointer, n uintptr) {
-	libcCall(unsafe.Pointer(abi.FuncPCABI0(munmap_trampoline)), unsafe.Pointer(&addr))
-	KeepAlive(addr) // Just for consistency. Hopefully addr is not a Go address.
-}
-func munmap_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func madvise(addr unsafe.Pointer, n uintptr, flags int32) {
-	libcCall(unsafe.Pointer(abi.FuncPCABI0(madvise_trampoline)), unsafe.Pointer(&addr))
-	KeepAlive(addr) // Just for consistency. Hopefully addr is not a Go address.
-}
-func madvise_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func mlock(addr unsafe.Pointer, n uintptr) {
-	libcCall(unsafe.Pointer(abi.FuncPCABI0(mlock_trampoline)), unsafe.Pointer(&addr))
-	KeepAlive(addr) // Just for consistency. Hopefully addr is not a Go address.
-}
-func mlock_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func read(fd int32, p unsafe.Pointer, n int32) int32 {
-	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(read_trampoline)), unsafe.Pointer(&fd))
-	KeepAlive(p)
-	return ret
-}
-func read_trampoline()
-
-func pipe() (r, w int32, errno int32) {
-	var p [2]int32
-	errno = libcCall(unsafe.Pointer(abi.FuncPCABI0(pipe_trampoline)), noescape(unsafe.Pointer(&p)))
-	return p[0], p[1], errno
-}
-func pipe_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func closefd(fd int32) int32 {
-	return libcCall(unsafe.Pointer(abi.FuncPCABI0(close_trampoline)), unsafe.Pointer(&fd))
-}
-func close_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-//
-// This is exported via linkname to assembly in runtime/cgo.
-//go:linkname exit
-func exit(code int32) {
-	libcCall(unsafe.Pointer(abi.FuncPCABI0(exit_trampoline)), unsafe.Pointer(&code))
-}
-func exit_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func usleep(usec uint32) {
-	libcCall(unsafe.Pointer(abi.FuncPCABI0(usleep_trampoline)), unsafe.Pointer(&usec))
-}
-func usleep_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func usleep_no_g(usec uint32) {
-	asmcgocall_no_g(unsafe.Pointer(abi.FuncPCABI0(usleep_trampoline)), unsafe.Pointer(&usec))
-}
-
-//go:nosplit
-//go:cgo_unsafe_args
-func write1(fd uintptr, p unsafe.Pointer, n int32) int32 {
-	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(write_trampoline)), unsafe.Pointer(&fd))
-	KeepAlive(p)
-	return ret
-}
-func write_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func open(name *byte, mode, perm int32) (ret int32) {
-	ret = libcCall(unsafe.Pointer(abi.FuncPCABI0(open_trampoline)), unsafe.Pointer(&name))
-	KeepAlive(name)
-	return
-}
-func open_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func nanotime1() int64 {
-	var r struct {
-		t            int64  // raw timer
-		numer, denom uint32 // conversion factors. nanoseconds = t * numer / denom.
-	}
-	libcCall(unsafe.Pointer(abi.FuncPCABI0(nanotime_trampoline)), unsafe.Pointer(&r))
-	// Note: Apple seems unconcerned about overflow here. See
-	// https://developer.apple.com/library/content/qa/qa1398/_index.html
-	// Note also, numer == denom == 1 is common.
-	t := r.t
-	if r.numer != 1 {
-		t *= int64(r.numer)
-	}
-	if r.denom != 1 {
-		t /= int64(r.denom)
-	}
-	return t
-}
-func nanotime_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func walltime() (int64, int32) {
-	var t timespec
-	libcCall(unsafe.Pointer(abi.FuncPCABI0(walltime_trampoline)), unsafe.Pointer(&t))
-	return t.tv_sec, int32(t.tv_nsec)
-}
-func walltime_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func sigaction(sig uint32, new *usigactiont, old *usigactiont) {
-	libcCall(unsafe.Pointer(abi.FuncPCABI0(sigaction_trampoline)), unsafe.Pointer(&sig))
-	KeepAlive(new)
-	KeepAlive(old)
-}
-func sigaction_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func sigprocmask(how uint32, new *sigset, old *sigset) {
-	libcCall(unsafe.Pointer(abi.FuncPCABI0(sigprocmask_trampoline)), unsafe.Pointer(&how))
-	KeepAlive(new)
-	KeepAlive(old)
-}
-func sigprocmask_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func sigaltstack(new *stackt, old *stackt) {
-	if new != nil && new.ss_flags&_SS_DISABLE != 0 && new.ss_size == 0 {
-		// Despite the fact that Darwin's sigaltstack man page says it ignores the size
-		// when SS_DISABLE is set, it doesn't. sigaltstack returns ENOMEM
-		// if we don't give it a reasonable size.
-		// ref: http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20140421/214296.html
-		new.ss_size = 32768
-	}
-	libcCall(unsafe.Pointer(abi.FuncPCABI0(sigaltstack_trampoline)), unsafe.Pointer(&new))
-	KeepAlive(new)
-	KeepAlive(old)
-}
-func sigaltstack_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func raiseproc(sig uint32) {
-	libcCall(unsafe.Pointer(abi.FuncPCABI0(raiseproc_trampoline)), unsafe.Pointer(&sig))
-}
-func raiseproc_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func setitimer(mode int32, new, old *itimerval) {
-	libcCall(unsafe.Pointer(abi.FuncPCABI0(setitimer_trampoline)), unsafe.Pointer(&mode))
-	KeepAlive(new)
-	KeepAlive(old)
-}
-func setitimer_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func sysctl(mib *uint32, miblen uint32, oldp *byte, oldlenp *uintptr, newp *byte, newlen uintptr) int32 {
-	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(sysctl_trampoline)), unsafe.Pointer(&mib))
-	KeepAlive(mib)
-	KeepAlive(oldp)
-	KeepAlive(oldlenp)
-	KeepAlive(newp)
-	return ret
-}
-func sysctl_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func sysctlbyname(name *byte, oldp *byte, oldlenp *uintptr, newp *byte, newlen uintptr) int32 {
-	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(sysctlbyname_trampoline)), unsafe.Pointer(&name))
-	KeepAlive(name)
-	KeepAlive(oldp)
-	KeepAlive(oldlenp)
-	KeepAlive(newp)
-	return ret
-}
-func sysctlbyname_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func fcntl(fd, cmd, arg int32) int32 {
-	return libcCall(unsafe.Pointer(abi.FuncPCABI0(fcntl_trampoline)), unsafe.Pointer(&fd))
-}
-func fcntl_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func kqueue() int32 {
-	v := libcCall(unsafe.Pointer(abi.FuncPCABI0(kqueue_trampoline)), nil)
-	return v
-}
-func kqueue_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func kevent(kq int32, ch *keventt, nch int32, ev *keventt, nev int32, ts *timespec) int32 {
-	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(kevent_trampoline)), unsafe.Pointer(&kq))
-	KeepAlive(ch)
-	KeepAlive(ev)
-	KeepAlive(ts)
-	return ret
-}
-func kevent_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func pthread_mutex_init(m *pthreadmutex, attr *pthreadmutexattr) int32 {
-	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(pthread_mutex_init_trampoline)), unsafe.Pointer(&m))
-	KeepAlive(m)
-	KeepAlive(attr)
-	return ret
-}
-func pthread_mutex_init_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func pthread_mutex_lock(m *pthreadmutex) int32 {
-	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(pthread_mutex_lock_trampoline)), unsafe.Pointer(&m))
-	KeepAlive(m)
-	return ret
-}
-func pthread_mutex_lock_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func pthread_mutex_unlock(m *pthreadmutex) int32 {
-	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(pthread_mutex_unlock_trampoline)), unsafe.Pointer(&m))
-	KeepAlive(m)
-	return ret
-}
-func pthread_mutex_unlock_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func pthread_cond_init(c *pthreadcond, attr *pthreadcondattr) int32 {
-	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(pthread_cond_init_trampoline)), unsafe.Pointer(&c))
-	KeepAlive(c)
-	KeepAlive(attr)
-	return ret
-}
-func pthread_cond_init_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func pthread_cond_wait(c *pthreadcond, m *pthreadmutex) int32 {
-	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(pthread_cond_wait_trampoline)), unsafe.Pointer(&c))
-	KeepAlive(c)
-	KeepAlive(m)
-	return ret
-}
-func pthread_cond_wait_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func pthread_cond_timedwait_relative_np(c *pthreadcond, m *pthreadmutex, t *timespec) int32 {
-	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(pthread_cond_timedwait_relative_np_trampoline)), unsafe.Pointer(&c))
-	KeepAlive(c)
-	KeepAlive(m)
-	KeepAlive(t)
-	return ret
-}
-func pthread_cond_timedwait_relative_np_trampoline()
-
-//go:nosplit
-//go:cgo_unsafe_args
-func pthread_cond_signal(c *pthreadcond) int32 {
-	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(pthread_cond_signal_trampoline)), unsafe.Pointer(&c))
-	KeepAlive(c)
-	return ret
-}
-func pthread_cond_signal_trampoline()
-
-// Not used on Darwin, but must be defined.
-func exitThread(wait *uint32) {
-}
-
-//go:nosplit
-func closeonexec(fd int32) {
-	fcntl(fd, _F_SETFD, _FD_CLOEXEC)
-}
-
-//go:nosplit
-func setNonblock(fd int32) {
-	flags := fcntl(fd, _F_GETFL, 0)
-	fcntl(fd, _F_SETFL, flags|_O_NONBLOCK)
-}
-
-// Tell the linker that the libc_* functions are to be found
-// in a system library, with the libc_ prefix missing.
-
-//go:cgo_import_dynamic libc_pthread_attr_init pthread_attr_init "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_pthread_attr_getstacksize pthread_attr_getstacksize "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_pthread_attr_setdetachstate pthread_attr_setdetachstate "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_pthread_create pthread_create "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_pthread_self pthread_self "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_pthread_kill pthread_kill "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_exit _exit "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_raise raise "/usr/lib/libSystem.B.dylib"
-
-//go:cgo_import_dynamic libc_open open "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_close close "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_read read "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_write write "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_pipe pipe "/usr/lib/libSystem.B.dylib"
-
-//go:cgo_import_dynamic libc_mmap mmap "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_munmap munmap "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_madvise madvise "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_mlock mlock "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_error __error "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_usleep usleep "/usr/lib/libSystem.B.dylib"
-
-//go:cgo_import_dynamic libc_mach_timebase_info mach_timebase_info "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_mach_absolute_time mach_absolute_time "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_clock_gettime clock_gettime "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_sigaction sigaction "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_pthread_sigmask pthread_sigmask "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_sigaltstack sigaltstack "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_getpid getpid "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_kill kill "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_setitimer setitimer "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_sysctl sysctl "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_sysctlbyname sysctlbyname "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_fcntl fcntl "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_kqueue kqueue "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_kevent kevent "/usr/lib/libSystem.B.dylib"
-
-//go:cgo_import_dynamic libc_pthread_mutex_init pthread_mutex_init "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_pthread_mutex_lock pthread_mutex_lock "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_pthread_mutex_unlock pthread_mutex_unlock "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_pthread_cond_init pthread_cond_init "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_pthread_cond_wait pthread_cond_wait "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_pthread_cond_timedwait_relative_np pthread_cond_timedwait_relative_np "/usr/lib/libSystem.B.dylib"
-//go:cgo_import_dynamic libc_pthread_cond_signal pthread_cond_signal "/usr/lib/libSystem.B.dylib"
diff --git a/contrib/go/_std_1.18/src/runtime/sys_darwin_amd64.s b/contrib/go/_std_1.18/src/runtime/sys_darwin_amd64.s
deleted file mode 100644
index db4715d2b7..0000000000
--- a/contrib/go/_std_1.18/src/runtime/sys_darwin_amd64.s
+++ /dev/null
@@ -1,859 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// System calls and other sys.stuff for AMD64, Darwin
-// System calls are implemented in libSystem, this file contains
-// trampolines that convert from Go to C calling convention.
-
-#include "go_asm.h"
-#include "go_tls.h"
-#include "textflag.h"
-#include "cgo/abi_amd64.h"
-
-#define CLOCK_REALTIME		0
-
-// Exit the entire program (like C exit)
-TEXT runtime·exit_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVL	0(DI), DI		// arg 1 exit status
-	CALL	libc_exit(SB)
-	MOVL	$0xf1, 0xf1  // crash
-	POPQ	BP
-	RET
-
-TEXT runtime·open_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVL	8(DI), SI		// arg 2 flags
-	MOVL	12(DI), DX		// arg 3 mode
-	MOVQ	0(DI), DI		// arg 1 pathname
-	XORL	AX, AX			// vararg: say "no float args"
-	CALL	libc_open(SB)
-	POPQ	BP
-	RET
-
-TEXT runtime·close_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVL	0(DI), DI		// arg 1 fd
-	CALL	libc_close(SB)
-	POPQ	BP
-	RET
-
-TEXT runtime·read_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVQ	8(DI), SI		// arg 2 buf
-	MOVL	16(DI), DX		// arg 3 count
-	MOVL	0(DI), DI		// arg 1 fd
-	CALL	libc_read(SB)
-	TESTL	AX, AX
-	JGE	noerr
-	CALL	libc_error(SB)
-	MOVL	(AX), AX
-	NEGL	AX			// caller expects negative errno value
-noerr:
-	POPQ	BP
-	RET
-
-TEXT runtime·write_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVQ	8(DI), SI		// arg 2 buf
-	MOVL	16(DI), DX		// arg 3 count
-	MOVQ	0(DI), DI		// arg 1 fd
-	CALL	libc_write(SB)
-	TESTL	AX, AX
-	JGE	noerr
-	CALL	libc_error(SB)
-	MOVL	(AX), AX
-	NEGL	AX			// caller expects negative errno value
-noerr:
-	POPQ	BP
-	RET
-
-TEXT runtime·pipe_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	CALL	libc_pipe(SB)		// pointer already in DI
-	TESTL	AX, AX
-	JEQ	3(PC)
-	CALL	libc_error(SB)		// return negative errno value
-	NEGL	AX
-	POPQ	BP
-	RET
-
-TEXT runtime·setitimer_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVQ	8(DI), SI		// arg 2 new
-	MOVQ	16(DI), DX		// arg 3 old
-	MOVL	0(DI), DI		// arg 1 which
-	CALL	libc_setitimer(SB)
-	POPQ	BP
-	RET
-
-TEXT runtime·madvise_trampoline(SB), NOSPLIT, $0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVQ	8(DI), SI	// arg 2 len
-	MOVL	16(DI), DX	// arg 3 advice
-	MOVQ	0(DI), DI	// arg 1 addr
-	CALL	libc_madvise(SB)
-	// ignore failure - maybe pages are locked
-	POPQ	BP
-	RET
-
-TEXT runtime·mlock_trampoline(SB), NOSPLIT, $0
-	UNDEF // unimplemented
-
-GLOBL timebase<>(SB),NOPTR,$(machTimebaseInfo__size)
-
-TEXT runtime·nanotime_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVQ	DI, BX
-	CALL	libc_mach_absolute_time(SB)
-	MOVQ	AX, 0(BX)
-	MOVL	timebase<>+machTimebaseInfo_numer(SB), SI
-	MOVL	timebase<>+machTimebaseInfo_denom(SB), DI // atomic read
-	TESTL	DI, DI
-	JNE	initialized
-
-	SUBQ	$(machTimebaseInfo__size+15)/16*16, SP
-	MOVQ	SP, DI
-	CALL	libc_mach_timebase_info(SB)
-	MOVL	machTimebaseInfo_numer(SP), SI
-	MOVL	machTimebaseInfo_denom(SP), DI
-	ADDQ	$(machTimebaseInfo__size+15)/16*16, SP
-
-	MOVL	SI, timebase<>+machTimebaseInfo_numer(SB)
-	MOVL	DI, AX
-	XCHGL	AX, timebase<>+machTimebaseInfo_denom(SB) // atomic write
-
-initialized:
-	MOVL	SI, 8(BX)
-	MOVL	DI, 12(BX)
-	MOVQ	BP, SP
-	POPQ	BP
-	RET
-
-TEXT runtime·walltime_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP			// make a frame; keep stack aligned
-	MOVQ	SP, BP
-	MOVQ	DI, SI			// arg 2 timespec
-	MOVL	$CLOCK_REALTIME, DI	// arg 1 clock_id
-	CALL	libc_clock_gettime(SB)
-	POPQ	BP
-	RET
-
-TEXT runtime·sigaction_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVQ	8(DI), SI		// arg 2 new
-	MOVQ	16(DI), DX		// arg 3 old
-	MOVL	0(DI), DI		// arg 1 sig
-	CALL	libc_sigaction(SB)
-	TESTL	AX, AX
-	JEQ	2(PC)
-	MOVL	$0xf1, 0xf1  // crash
-	POPQ	BP
-	RET
-
-TEXT runtime·sigprocmask_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVQ	8(DI), SI	// arg 2 new
-	MOVQ	16(DI), DX	// arg 3 old
-	MOVL	0(DI), DI	// arg 1 how
-	CALL	libc_pthread_sigmask(SB)
-	TESTL	AX, AX
-	JEQ	2(PC)
-	MOVL	$0xf1, 0xf1  // crash
-	POPQ	BP
-	RET
-
-TEXT runtime·sigaltstack_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVQ	8(DI), SI		// arg 2 old
-	MOVQ	0(DI), DI		// arg 1 new
-	CALL	libc_sigaltstack(SB)
-	TESTQ	AX, AX
-	JEQ	2(PC)
-	MOVL	$0xf1, 0xf1  // crash
-	POPQ	BP
-	RET
-
-TEXT runtime·raiseproc_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVL	0(DI), BX	// signal
-	CALL	libc_getpid(SB)
-	MOVL	AX, DI		// arg 1 pid
-	MOVL	BX, SI		// arg 2 signal
-	CALL	libc_kill(SB)
-	POPQ	BP
-	RET
-
-TEXT runtime·sigfwd(SB),NOSPLIT,$0-32
-	MOVQ	fn+0(FP),    AX
-	MOVL	sig+8(FP),   DI
-	MOVQ	info+16(FP), SI
-	MOVQ	ctx+24(FP),  DX
-	PUSHQ	BP
-	MOVQ	SP, BP
-	ANDQ	$~15, SP     // alignment for x86_64 ABI
-	CALL	AX
-	MOVQ	BP, SP
-	POPQ	BP
-	RET
-
-// This is the function registered during sigaction and is invoked when
-// a signal is received. It just redirects to the Go function sigtrampgo.
-// Called using C ABI.
-TEXT runtime·sigtramp(SB),NOSPLIT,$0
-	// Transition from C ABI to Go ABI.
-	PUSH_REGS_HOST_TO_ABI0()
-
-	// Call into the Go signal handler
-	NOP	SP		// disable vet stack checking
-	ADJSP	$24
-	MOVL	DI, 0(SP)	// sig
-	MOVQ	SI, 8(SP)	// info
-	MOVQ	DX, 16(SP)	// ctx
-	CALL	·sigtrampgo(SB)
-	ADJSP	$-24
-
-	POP_REGS_HOST_TO_ABI0()
-	RET
-
-// Called using C ABI.
-TEXT runtime·sigprofNonGoWrapper<>(SB),NOSPLIT,$0
-	// Transition from C ABI to Go ABI.
-	PUSH_REGS_HOST_TO_ABI0()
-
-	// Call into the Go signal handler
-	NOP	SP		// disable vet stack checking
-	ADJSP	$24
-	MOVL	DI, 0(SP)	// sig
-	MOVQ	SI, 8(SP)	// info
-	MOVQ	DX, 16(SP)	// ctx
-	CALL	·sigprofNonGo(SB)
-	ADJSP	$-24
-
-	POP_REGS_HOST_TO_ABI0()
-	RET
-
-// Used instead of sigtramp in programs that use cgo.
-// Arguments from kernel are in DI, SI, DX.
-TEXT runtime·cgoSigtramp(SB),NOSPLIT,$0
-	// If no traceback function, do usual sigtramp.
-	MOVQ	runtime·cgoTraceback(SB), AX
-	TESTQ	AX, AX
-	JZ	sigtramp
-
-	// If no traceback support function, which means that
-	// runtime/cgo was not linked in, do usual sigtramp.
-	MOVQ	_cgo_callers(SB), AX
-	TESTQ	AX, AX
-	JZ	sigtramp
-
-	// Figure out if we are currently in a cgo call.
-	// If not, just do usual sigtramp.
-	get_tls(CX)
-	MOVQ	g(CX),AX
-	TESTQ	AX, AX
-	JZ	sigtrampnog     // g == nil
-	MOVQ	g_m(AX), AX
-	TESTQ	AX, AX
-	JZ	sigtramp        // g.m == nil
-	MOVL	m_ncgo(AX), CX
-	TESTL	CX, CX
-	JZ	sigtramp        // g.m.ncgo == 0
-	MOVQ	m_curg(AX), CX
-	TESTQ	CX, CX
-	JZ	sigtramp        // g.m.curg == nil
-	MOVQ	g_syscallsp(CX), CX
-	TESTQ	CX, CX
-	JZ	sigtramp        // g.m.curg.syscallsp == 0
-	MOVQ	m_cgoCallers(AX), R8
-	TESTQ	R8, R8
-	JZ	sigtramp        // g.m.cgoCallers == nil
-	MOVL	m_cgoCallersUse(AX), CX
-	TESTL	CX, CX
-	JNZ	sigtramp	// g.m.cgoCallersUse != 0
-
-	// Jump to a function in runtime/cgo.
-	// That function, written in C, will call the user's traceback
-	// function with proper unwind info, and will then call back here.
-	// The first three arguments, and the fifth, are already in registers.
-	// Set the two remaining arguments now.
-	MOVQ	runtime·cgoTraceback(SB), CX
-	MOVQ	$runtime·sigtramp(SB), R9
-	MOVQ	_cgo_callers(SB), AX
-	JMP	AX
-
-sigtramp:
-	JMP	runtime·sigtramp(SB)
-
-sigtrampnog:
-	// Signal arrived on a non-Go thread. If this is SIGPROF, get a
-	// stack trace.
-	CMPL	DI, $27 // 27 == SIGPROF
-	JNZ	sigtramp
-
-	// Lock sigprofCallersUse.
-	MOVL	$0, AX
-	MOVL	$1, CX
-	MOVQ	$runtime·sigprofCallersUse(SB), R11
-	LOCK
-	CMPXCHGL	CX, 0(R11)
-	JNZ	sigtramp  // Skip stack trace if already locked.
-
-	// Jump to the traceback function in runtime/cgo.
-	// It will call back to sigprofNonGo, via sigprofNonGoWrapper, to convert
-	// the arguments to the Go calling convention.
-	// First three arguments to traceback function are in registers already.
-	MOVQ	runtime·cgoTraceback(SB), CX
-	MOVQ	$runtime·sigprofCallers(SB), R8
-	MOVQ	$runtime·sigprofNonGoWrapper<>(SB), R9
-	MOVQ	_cgo_callers(SB), AX
-	JMP	AX
-
-TEXT runtime·mmap_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP			// make a frame; keep stack aligned
-	MOVQ	SP, BP
-	MOVQ	DI, BX
-	MOVQ	0(BX), DI		// arg 1 addr
-	MOVQ	8(BX), SI		// arg 2 len
-	MOVL	16(BX), DX		// arg 3 prot
-	MOVL	20(BX), CX		// arg 4 flags
-	MOVL	24(BX), R8		// arg 5 fid
-	MOVL	28(BX), R9		// arg 6 offset
-	CALL	libc_mmap(SB)
-	XORL	DX, DX
-	CMPQ	AX, $-1
-	JNE	ok
-	CALL	libc_error(SB)
-	MOVLQSX	(AX), DX		// errno
-	XORL	AX, AX
-ok:
-	MOVQ	AX, 32(BX)
-	MOVQ	DX, 40(BX)
-	POPQ	BP
-	RET
-
-TEXT runtime·munmap_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVQ	8(DI), SI		// arg 2 len
-	MOVQ	0(DI), DI		// arg 1 addr
-	CALL	libc_munmap(SB)
-	TESTQ	AX, AX
-	JEQ	2(PC)
-	MOVL	$0xf1, 0xf1  // crash
-	POPQ	BP
-	RET
-
-TEXT runtime·usleep_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVL	0(DI), DI	// arg 1 usec
-	CALL	libc_usleep(SB)
-	POPQ	BP
-	RET
-
-TEXT runtime·settls(SB),NOSPLIT,$32
-	// Nothing to do on Darwin, pthread already set thread-local storage up.
-	RET
-
-TEXT runtime·sysctl_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVL	8(DI), SI		// arg 2 miblen
-	MOVQ	16(DI), DX		// arg 3 oldp
-	MOVQ	24(DI), CX		// arg 4 oldlenp
-	MOVQ	32(DI), R8		// arg 5 newp
-	MOVQ	40(DI), R9		// arg 6 newlen
-	MOVQ	0(DI), DI		// arg 1 mib
-	CALL	libc_sysctl(SB)
-	POPQ	BP
-	RET
-
-TEXT runtime·sysctlbyname_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVQ	8(DI), SI		// arg 2 oldp
-	MOVQ	16(DI), DX		// arg 3 oldlenp
-	MOVQ	24(DI), CX		// arg 4 newp
-	MOVQ	32(DI), R8		// arg 5 newlen
-	MOVQ	0(DI), DI		// arg 1 name
-	CALL	libc_sysctlbyname(SB)
-	POPQ	BP
-	RET
-
-TEXT runtime·kqueue_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	CALL	libc_kqueue(SB)
-	POPQ	BP
-	RET
-
-TEXT runtime·kevent_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVQ	8(DI), SI		// arg 2 keventt
-	MOVL	16(DI), DX		// arg 3 nch
-	MOVQ	24(DI), CX		// arg 4 ev
-	MOVL	32(DI), R8		// arg 5 nev
-	MOVQ	40(DI), R9		// arg 6 ts
-	MOVL	0(DI), DI		// arg 1 kq
-	CALL	libc_kevent(SB)
-	CMPL	AX, $-1
-	JNE	ok
-	CALL	libc_error(SB)
-	MOVLQSX	(AX), AX		// errno
-	NEGQ	AX			// caller wants it as a negative error code
-ok:
-	POPQ	BP
-	RET
-
-TEXT runtime·fcntl_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVL	4(DI), SI		// arg 2 cmd
-	MOVL	8(DI), DX		// arg 3 arg
-	MOVL	0(DI), DI		// arg 1 fd
-	XORL	AX, AX			// vararg: say "no float args"
-	CALL	libc_fcntl(SB)
-	POPQ	BP
-	RET
-
-// mstart_stub is the first function executed on a new thread started by pthread_create.
-// It just does some low-level setup and then calls mstart.
-// Note: called with the C calling convention.
-TEXT runtime·mstart_stub(SB),NOSPLIT,$0
-	// DI points to the m.
-	// We are already on m's g0 stack.
-
-	// Transition from C ABI to Go ABI.
-	PUSH_REGS_HOST_TO_ABI0()
-
-	MOVQ	m_g0(DI), DX // g
-
-	// Initialize TLS entry.
-	// See cmd/link/internal/ld/sym.go:computeTLSOffset.
-	MOVQ	DX, 0x30(GS)
-
-	CALL	runtime·mstart(SB)
-
-	POP_REGS_HOST_TO_ABI0()
-
-	// Go is all done with this OS thread.
-	// Tell pthread everything is ok (we never join with this thread, so
-	// the value here doesn't really matter).
-	XORL	AX, AX
-	RET
-
-// These trampolines help convert from Go calling convention to C calling convention.
-// They should be called with asmcgocall.
-// A pointer to the arguments is passed in DI.
-// A single int32 result is returned in AX.
-// (For more results, make an args/results structure.)
-TEXT runtime·pthread_attr_init_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP	// make frame, keep stack 16-byte aligned.
-	MOVQ	SP, BP
-	MOVQ	0(DI), DI // arg 1 attr
-	CALL	libc_pthread_attr_init(SB)
-	POPQ	BP
-	RET
-
-TEXT runtime·pthread_attr_getstacksize_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVQ	8(DI), SI	// arg 2 size
-	MOVQ	0(DI), DI	// arg 1 attr
-	CALL	libc_pthread_attr_getstacksize(SB)
-	POPQ	BP
-	RET
-
-TEXT runtime·pthread_attr_setdetachstate_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVQ	8(DI), SI	// arg 2 state
-	MOVQ	0(DI), DI	// arg 1 attr
-	CALL	libc_pthread_attr_setdetachstate(SB)
-	POPQ	BP
-	RET
-
-TEXT runtime·pthread_create_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	SUBQ	$16, SP
-	MOVQ	0(DI), SI	// arg 2 attr
-	MOVQ	8(DI), DX	// arg 3 start
-	MOVQ	16(DI), CX	// arg 4 arg
-	MOVQ	SP, DI		// arg 1 &threadid (which we throw away)
-	CALL	libc_pthread_create(SB)
-	MOVQ	BP, SP
-	POPQ	BP
-	RET
-
-TEXT runtime·raise_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVL	0(DI), DI	// arg 1 signal
-	CALL	libc_raise(SB)
-	POPQ	BP
-	RET
-
-TEXT runtime·pthread_mutex_init_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVQ	8(DI), SI	// arg 2 attr
-	MOVQ	0(DI), DI	// arg 1 mutex
-	CALL	libc_pthread_mutex_init(SB)
-	POPQ	BP
-	RET
-
-TEXT runtime·pthread_mutex_lock_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVQ	0(DI), DI	// arg 1 mutex
-	CALL	libc_pthread_mutex_lock(SB)
-	POPQ	BP
-	RET
-
-TEXT runtime·pthread_mutex_unlock_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVQ	0(DI), DI	// arg 1 mutex
-	CALL	libc_pthread_mutex_unlock(SB)
-	POPQ	BP
-	RET
-
-TEXT runtime·pthread_cond_init_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVQ	8(DI), SI	// arg 2 attr
-	MOVQ	0(DI), DI	// arg 1 cond
-	CALL	libc_pthread_cond_init(SB)
-	POPQ	BP
-	RET
-
-TEXT runtime·pthread_cond_wait_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVQ	8(DI), SI	// arg 2 mutex
-	MOVQ	0(DI), DI	// arg 1 cond
-	CALL	libc_pthread_cond_wait(SB)
-	POPQ	BP
-	RET
-
-TEXT runtime·pthread_cond_timedwait_relative_np_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVQ	8(DI), SI	// arg 2 mutex
-	MOVQ	16(DI), DX	// arg 3 timeout
-	MOVQ	0(DI), DI	// arg 1 cond
-	CALL	libc_pthread_cond_timedwait_relative_np(SB)
-	POPQ	BP
-	RET
-
-TEXT runtime·pthread_cond_signal_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVQ	0(DI), DI	// arg 1 cond
-	CALL	libc_pthread_cond_signal(SB)
-	POPQ	BP
-	RET
-
-TEXT runtime·pthread_self_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVQ	DI, BX		// BX is caller-save
-	CALL	libc_pthread_self(SB)
-	MOVQ	AX, 0(BX)	// return value
-	POPQ	BP
-	RET
-
-TEXT runtime·pthread_kill_trampoline(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	MOVQ	8(DI), SI	// arg 2 sig
-	MOVQ	0(DI), DI	// arg 1 thread
-	CALL	libc_pthread_kill(SB)
-	POPQ	BP
-	RET
-
-// syscall calls a function in libc on behalf of the syscall package.
-// syscall takes a pointer to a struct like:
-// struct {
-//	fn    uintptr
-//	a1    uintptr
-//	a2    uintptr
-//	a3    uintptr
-//	r1    uintptr
-//	r2    uintptr
-//	err   uintptr
-// }
-// syscall must be called on the g0 stack with the
-// C calling convention (use libcCall).
-//
-// syscall expects a 32-bit result and tests for 32-bit -1
-// to decide there was an error.
-TEXT runtime·syscall(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	SUBQ	$16, SP
-	MOVQ	(0*8)(DI), CX // fn
-	MOVQ	(2*8)(DI), SI // a2
-	MOVQ	(3*8)(DI), DX // a3
-	MOVQ	DI, (SP)
-	MOVQ	(1*8)(DI), DI // a1
-	XORL	AX, AX	      // vararg: say "no float args"
-
-	CALL	CX
-
-	MOVQ	(SP), DI
-	MOVQ	AX, (4*8)(DI) // r1
-	MOVQ	DX, (5*8)(DI) // r2
-
-	// Standard libc functions return -1 on error
-	// and set errno.
-	CMPL	AX, $-1	      // Note: high 32 bits are junk
-	JNE	ok
-
-	// Get error code from libc.
-	CALL	libc_error(SB)
-	MOVLQSX	(AX), AX
-	MOVQ	(SP), DI
-	MOVQ	AX, (6*8)(DI) // err
-
-ok:
-	XORL	AX, AX        // no error (it's ignored anyway)
-	MOVQ	BP, SP
-	POPQ	BP
-	RET
-
-// syscallX calls a function in libc on behalf of the syscall package.
-// syscallX takes a pointer to a struct like:
-// struct {
-//	fn    uintptr
-//	a1    uintptr
-//	a2    uintptr
-//	a3    uintptr
-//	r1    uintptr
-//	r2    uintptr
-//	err   uintptr
-// }
-// syscallX must be called on the g0 stack with the
-// C calling convention (use libcCall).
-//
-// syscallX is like syscall but expects a 64-bit result
-// and tests for 64-bit -1 to decide there was an error.
-TEXT runtime·syscallX(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	SUBQ	$16, SP
-	MOVQ	(0*8)(DI), CX // fn
-	MOVQ	(2*8)(DI), SI // a2
-	MOVQ	(3*8)(DI), DX // a3
-	MOVQ	DI, (SP)
-	MOVQ	(1*8)(DI), DI // a1
-	XORL	AX, AX	      // vararg: say "no float args"
-
-	CALL	CX
-
-	MOVQ	(SP), DI
-	MOVQ	AX, (4*8)(DI) // r1
-	MOVQ	DX, (5*8)(DI) // r2
-
-	// Standard libc functions return -1 on error
-	// and set errno.
-	CMPQ	AX, $-1
-	JNE	ok
-
-	// Get error code from libc.
-	CALL	libc_error(SB)
-	MOVLQSX	(AX), AX
-	MOVQ	(SP), DI
-	MOVQ	AX, (6*8)(DI) // err
-
-ok:
-	XORL	AX, AX        // no error (it's ignored anyway)
-	MOVQ	BP, SP
-	POPQ	BP
-	RET
-
-// syscallPtr is like syscallX except that the libc function reports an
-// error by returning NULL and setting errno.
-TEXT runtime·syscallPtr(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	SUBQ	$16, SP
-	MOVQ	(0*8)(DI), CX // fn
-	MOVQ	(2*8)(DI), SI // a2
-	MOVQ	(3*8)(DI), DX // a3
-	MOVQ	DI, (SP)
-	MOVQ	(1*8)(DI), DI // a1
-	XORL	AX, AX	      // vararg: say "no float args"
-
-	CALL	CX
-
-	MOVQ	(SP), DI
-	MOVQ	AX, (4*8)(DI) // r1
-	MOVQ	DX, (5*8)(DI) // r2
-
-	// syscallPtr libc functions return NULL on error
-	// and set errno.
-	TESTQ	AX, AX
-	JNE	ok
-
-	// Get error code from libc.
-	CALL	libc_error(SB)
-	MOVLQSX	(AX), AX
-	MOVQ	(SP), DI
-	MOVQ	AX, (6*8)(DI) // err
-
-ok:
-	XORL	AX, AX        // no error (it's ignored anyway)
-	MOVQ	BP, SP
-	POPQ	BP
-	RET
-
-// syscall6 calls a function in libc on behalf of the syscall package.
-// syscall6 takes a pointer to a struct like:
-// struct {
-//	fn    uintptr
-//	a1    uintptr
-//	a2    uintptr
-//	a3    uintptr
-//	a4    uintptr
-//	a5    uintptr
-//	a6    uintptr
-//	r1    uintptr
-//	r2    uintptr
-//	err   uintptr
-// }
-// syscall6 must be called on the g0 stack with the
-// C calling convention (use libcCall).
-//
-// syscall6 expects a 32-bit result and tests for 32-bit -1
-// to decide there was an error.
-TEXT runtime·syscall6(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	SUBQ	$16, SP
-	MOVQ	(0*8)(DI), R11// fn
-	MOVQ	(2*8)(DI), SI // a2
-	MOVQ	(3*8)(DI), DX // a3
-	MOVQ	(4*8)(DI), CX // a4
-	MOVQ	(5*8)(DI), R8 // a5
-	MOVQ	(6*8)(DI), R9 // a6
-	MOVQ	DI, (SP)
-	MOVQ	(1*8)(DI), DI // a1
-	XORL	AX, AX	      // vararg: say "no float args"
-
-	CALL	R11
-
-	MOVQ	(SP), DI
-	MOVQ	AX, (7*8)(DI) // r1
-	MOVQ	DX, (8*8)(DI) // r2
-
-	CMPL	AX, $-1
-	JNE	ok
-
-	CALL	libc_error(SB)
-	MOVLQSX	(AX), AX
-	MOVQ	(SP), DI
-	MOVQ	AX, (9*8)(DI) // err
-
-ok:
-	XORL	AX, AX        // no error (it's ignored anyway)
-	MOVQ	BP, SP
-	POPQ	BP
-	RET
-
-// syscall6X calls a function in libc on behalf of the syscall package.
-// syscall6X takes a pointer to a struct like:
-// struct {
-//	fn    uintptr
-//	a1    uintptr
-//	a2    uintptr
-//	a3    uintptr
-//	a4    uintptr
-//	a5    uintptr
-//	a6    uintptr
-//	r1    uintptr
-//	r2    uintptr
-//	err   uintptr
-// }
-// syscall6X must be called on the g0 stack with the
-// C calling convention (use libcCall).
-//
-// syscall6X is like syscall6 but expects a 64-bit result
-// and tests for 64-bit -1 to decide there was an error.
-TEXT runtime·syscall6X(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	SUBQ	$16, SP
-	MOVQ	(0*8)(DI), R11// fn
-	MOVQ	(2*8)(DI), SI // a2
-	MOVQ	(3*8)(DI), DX // a3
-	MOVQ	(4*8)(DI), CX // a4
-	MOVQ	(5*8)(DI), R8 // a5
-	MOVQ	(6*8)(DI), R9 // a6
-	MOVQ	DI, (SP)
-	MOVQ	(1*8)(DI), DI // a1
-	XORL	AX, AX	      // vararg: say "no float args"
-
-	CALL	R11
-
-	MOVQ	(SP), DI
-	MOVQ	AX, (7*8)(DI) // r1
-	MOVQ	DX, (8*8)(DI) // r2
-
-	CMPQ	AX, $-1
-	JNE	ok
-
-	CALL	libc_error(SB)
-	MOVLQSX	(AX), AX
-	MOVQ	(SP), DI
-	MOVQ	AX, (9*8)(DI) // err
-
-ok:
-	XORL	AX, AX        // no error (it's ignored anyway)
-	MOVQ	BP, SP
-	POPQ	BP
-	RET
-
-// syscall_x509 is for crypto/x509. It is like syscall6 but does not check for errors,
-// takes 5 uintptrs and 1 float64, and only returns one value,
-// for use with standard C ABI functions.
-TEXT runtime·syscall_x509(SB),NOSPLIT,$0
-	PUSHQ	BP
-	MOVQ	SP, BP
-	SUBQ	$16, SP
-	MOVQ	(0*8)(DI), R11// fn
-	MOVQ	(2*8)(DI), SI // a2
-	MOVQ	(3*8)(DI), DX // a3
-	MOVQ	(4*8)(DI), CX // a4
-	MOVQ	(5*8)(DI), R8 // a5
-	MOVQ	(6*8)(DI), X0 // f1
-	MOVQ	DI, (SP)
-	MOVQ	(1*8)(DI), DI // a1
-	XORL	AX, AX	      // vararg: say "no float args"
-
-	CALL	R11
-
-	MOVQ	(SP), DI
-	MOVQ	AX, (7*8)(DI) // r1
-
-	XORL	AX, AX        // no error (it's ignored anyway)
-	MOVQ	BP, SP
-	POPQ	BP
-	RET
diff --git a/contrib/go/_std_1.18/src/runtime/sys_libc.go b/contrib/go/_std_1.18/src/runtime/sys_libc.go
deleted file mode 100644
index 7012b4167e..0000000000
--- a/contrib/go/_std_1.18/src/runtime/sys_libc.go
+++ /dev/null
@@ -1,53 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build darwin || (openbsd && !mips64)
-
-package runtime
-
-import "unsafe"
-
-// Call fn with arg as its argument. Return what fn returns.
-// fn is the raw pc value of the entry point of the desired function.
-// Switches to the system stack, if not already there.
-// Preserves the calling point as the location where a profiler traceback will begin.
-//go:nosplit
-func libcCall(fn, arg unsafe.Pointer) int32 {
-	// Leave caller's PC/SP/G around for traceback.
-	gp := getg()
-	var mp *m
-	if gp != nil {
-		mp = gp.m
-	}
-	if mp != nil && mp.libcallsp == 0 {
-		mp.libcallg.set(gp)
-		mp.libcallpc = getcallerpc()
-		// sp must be the last, because once async cpu profiler finds
-		// all three values to be non-zero, it will use them
-		mp.libcallsp = getcallersp()
-	} else {
-		// Make sure we don't reset libcallsp. This makes
-		// libcCall reentrant; We remember the g/pc/sp for the
-		// first call on an M, until that libcCall instance
-		// returns.  Reentrance only matters for signals, as
-		// libc never calls back into Go.  The tricky case is
-		// where we call libcX from an M and record g/pc/sp.
-		// Before that call returns, a signal arrives on the
-		// same M and the signal handling code calls another
-		// libc function.  We don't want that second libcCall
-		// from within the handler to be recorded, and we
-		// don't want that call's completion to zero
-		// libcallsp.
-		// We don't need to set libcall* while we're in a sighandler
-		// (even if we're not currently in libc) because we block all
-		// signals while we're handling a signal. That includes the
-		// profile signal, which is the one that uses the libcall* info.
-		mp = nil
-	}
-	res := asmcgocall(fn, arg)
-	if mp != nil {
-		mp.libcallsp = 0
-	}
-	return res
-}
diff --git a/contrib/go/_std_1.18/src/runtime/sys_linux_amd64.s b/contrib/go/_std_1.18/src/runtime/sys_linux_amd64.s
deleted file mode 100644
index f0e58e11db..0000000000
--- a/contrib/go/_std_1.18/src/runtime/sys_linux_amd64.s
+++ /dev/null
@@ -1,765 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//
-// System calls and other sys.stuff for AMD64, Linux
-//
-
-#include "go_asm.h"
-#include "go_tls.h"
-#include "textflag.h"
-#include "cgo/abi_amd64.h"
-
-#define AT_FDCWD -100
-
-#define SYS_read		0
-#define SYS_write		1
-#define SYS_close		3
-#define SYS_mmap		9
-#define SYS_munmap		11
-#define SYS_brk 		12
-#define SYS_rt_sigaction	13
-#define SYS_rt_sigprocmask	14
-#define SYS_rt_sigreturn	15
-#define SYS_pipe		22
-#define SYS_sched_yield 	24
-#define SYS_mincore		27
-#define SYS_madvise		28
-#define SYS_nanosleep		35
-#define SYS_setittimer		38
-#define SYS_getpid		39
-#define SYS_socket		41
-#define SYS_connect		42
-#define SYS_clone		56
-#define SYS_exit		60
-#define SYS_kill		62
-#define SYS_fcntl		72
-#define SYS_sigaltstack 	131
-#define SYS_arch_prctl		158
-#define SYS_gettid		186
-#define SYS_futex		202
-#define SYS_sched_getaffinity	204
-#define SYS_epoll_create	213
-#define SYS_timer_create	222
-#define SYS_timer_settime	223
-#define SYS_timer_delete	226
-#define SYS_clock_gettime	228
-#define SYS_exit_group		231
-#define SYS_epoll_ctl		233
-#define SYS_tgkill		234
-#define SYS_openat		257
-#define SYS_faccessat		269
-#define SYS_epoll_pwait		281
-#define SYS_epoll_create1	291
-#define SYS_pipe2		293
-
-TEXT runtime·exit(SB),NOSPLIT,$0-4
-	MOVL	code+0(FP), DI
-	MOVL	$SYS_exit_group, AX
-	SYSCALL
-	RET
-
-// func exitThread(wait *uint32)
-TEXT runtime·exitThread(SB),NOSPLIT,$0-8
-	MOVQ	wait+0(FP), AX
-	// We're done using the stack.
-	MOVL	$0, (AX)
-	MOVL	$0, DI	// exit code
-	MOVL	$SYS_exit, AX
-	SYSCALL
-	// We may not even have a stack any more.
-	INT	$3
-	JMP	0(PC)
-
-TEXT runtime·open(SB),NOSPLIT,$0-20
-	// This uses openat instead of open, because Android O blocks open.
-	MOVL	$AT_FDCWD, DI // AT_FDCWD, so this acts like open
-	MOVQ	name+0(FP), SI
-	MOVL	mode+8(FP), DX
-	MOVL	perm+12(FP), R10
-	MOVL	$SYS_openat, AX
-	SYSCALL
-	CMPQ	AX, $0xfffffffffffff001
-	JLS	2(PC)
-	MOVL	$-1, AX
-	MOVL	AX, ret+16(FP)
-	RET
-
-TEXT runtime·closefd(SB),NOSPLIT,$0-12
-	MOVL	fd+0(FP), DI
-	MOVL	$SYS_close, AX
-	SYSCALL
-	CMPQ	AX, $0xfffffffffffff001
-	JLS	2(PC)
-	MOVL	$-1, AX
-	MOVL	AX, ret+8(FP)
-	RET
-
-TEXT runtime·write1(SB),NOSPLIT,$0-28
-	MOVQ	fd+0(FP), DI
-	MOVQ	p+8(FP), SI
-	MOVL	n+16(FP), DX
-	MOVL	$SYS_write, AX
-	SYSCALL
-	MOVL	AX, ret+24(FP)
-	RET
-
-TEXT runtime·read(SB),NOSPLIT,$0-28
-	MOVL	fd+0(FP), DI
-	MOVQ	p+8(FP), SI
-	MOVL	n+16(FP), DX
-	MOVL	$SYS_read, AX
-	SYSCALL
-	MOVL	AX, ret+24(FP)
-	RET
-
-// func pipe() (r, w int32, errno int32)
-TEXT runtime·pipe(SB),NOSPLIT,$0-12
-	LEAQ	r+0(FP), DI
-	MOVL	$SYS_pipe, AX
-	SYSCALL
-	MOVL	AX, errno+8(FP)
-	RET
-
-// func pipe2(flags int32) (r, w int32, errno int32)
-TEXT runtime·pipe2(SB),NOSPLIT,$0-20
-	LEAQ	r+8(FP), DI
-	MOVL	flags+0(FP), SI
-	MOVL	$SYS_pipe2, AX
-	SYSCALL
-	MOVL	AX, errno+16(FP)
-	RET
-
-TEXT runtime·usleep(SB),NOSPLIT,$16
-	MOVL	$0, DX
-	MOVL	usec+0(FP), AX
-	MOVL	$1000000, CX
-	DIVL	CX
-	MOVQ	AX, 0(SP)
-	MOVL	$1000, AX	// usec to nsec
-	MULL	DX
-	MOVQ	AX, 8(SP)
-
-	// nanosleep(&ts, 0)
-	MOVQ	SP, DI
-	MOVL	$0, SI
-	MOVL	$SYS_nanosleep, AX
-	SYSCALL
-	RET
-
-TEXT runtime·gettid(SB),NOSPLIT,$0-4
-	MOVL	$SYS_gettid, AX
-	SYSCALL
-	MOVL	AX, ret+0(FP)
-	RET
-
-TEXT runtime·raise(SB),NOSPLIT,$0
-	MOVL	$SYS_getpid, AX
-	SYSCALL
-	MOVL	AX, R12
-	MOVL	$SYS_gettid, AX
-	SYSCALL
-	MOVL	AX, SI	// arg 2 tid
-	MOVL	R12, DI	// arg 1 pid
-	MOVL	sig+0(FP), DX	// arg 3
-	MOVL	$SYS_tgkill, AX
-	SYSCALL
-	RET
-
-TEXT runtime·raiseproc(SB),NOSPLIT,$0
-	MOVL	$SYS_getpid, AX
-	SYSCALL
-	MOVL	AX, DI	// arg 1 pid
-	MOVL	sig+0(FP), SI	// arg 2
-	MOVL	$SYS_kill, AX
-	SYSCALL
-	RET
-
-TEXT ·getpid(SB),NOSPLIT,$0-8
-	MOVL	$SYS_getpid, AX
-	SYSCALL
-	MOVQ	AX, ret+0(FP)
-	RET
-
-TEXT ·tgkill(SB),NOSPLIT,$0
-	MOVQ	tgid+0(FP), DI
-	MOVQ	tid+8(FP), SI
-	MOVQ	sig+16(FP), DX
-	MOVL	$SYS_tgkill, AX
-	SYSCALL
-	RET
-
-TEXT runtime·setitimer(SB),NOSPLIT,$0-24
-	MOVL	mode+0(FP), DI
-	MOVQ	new+8(FP), SI
-	MOVQ	old+16(FP), DX
-	MOVL	$SYS_setittimer, AX
-	SYSCALL
-	RET
-
-TEXT runtime·timer_create(SB),NOSPLIT,$0-28
-	MOVL	clockid+0(FP), DI
-	MOVQ	sevp+8(FP), SI
-	MOVQ	timerid+16(FP), DX
-	MOVL	$SYS_timer_create, AX
-	SYSCALL
-	MOVL	AX, ret+24(FP)
-	RET
-
-TEXT runtime·timer_settime(SB),NOSPLIT,$0-28
-	MOVL	timerid+0(FP), DI
-	MOVL	flags+4(FP), SI
-	MOVQ	new+8(FP), DX
-	MOVQ	old+16(FP), R10
-	MOVL	$SYS_timer_settime, AX
-	SYSCALL
-	MOVL	AX, ret+24(FP)
-	RET
-
-TEXT runtime·timer_delete(SB),NOSPLIT,$0-12
-	MOVL	timerid+0(FP), DI
-	MOVL	$SYS_timer_delete, AX
-	SYSCALL
-	MOVL	AX, ret+8(FP)
-	RET
-
-TEXT runtime·mincore(SB),NOSPLIT,$0-28
-	MOVQ	addr+0(FP), DI
-	MOVQ	n+8(FP), SI
-	MOVQ	dst+16(FP), DX
-	MOVL	$SYS_mincore, AX
-	SYSCALL
-	MOVL	AX, ret+24(FP)
-	RET
-
-// func nanotime1() int64
-TEXT runtime·nanotime1(SB),NOSPLIT,$16-8
-	// We don't know how much stack space the VDSO code will need,
-	// so switch to g0.
-	// In particular, a kernel configured with CONFIG_OPTIMIZE_INLINING=n
-	// and hardening can use a full page of stack space in gettime_sym
-	// due to stack probes inserted to avoid stack/heap collisions.
-	// See issue #20427.
-
-	MOVQ	SP, R12	// Save old SP; R12 unchanged by C code.
-
-	MOVQ	g_m(R14), BX // BX unchanged by C code.
-
-	// Set vdsoPC and vdsoSP for SIGPROF traceback.
-	// Save the old values on stack and restore them on exit,
-	// so this function is reentrant.
-	MOVQ	m_vdsoPC(BX), CX
-	MOVQ	m_vdsoSP(BX), DX
-	MOVQ	CX, 0(SP)
-	MOVQ	DX, 8(SP)
-
-	LEAQ	ret+0(FP), DX
-	MOVQ	-8(DX), CX
-	MOVQ	CX, m_vdsoPC(BX)
-	MOVQ	DX, m_vdsoSP(BX)
-
-	CMPQ	R14, m_curg(BX)	// Only switch if on curg.
-	JNE	noswitch
-
-	MOVQ	m_g0(BX), DX
-	MOVQ	(g_sched+gobuf_sp)(DX), SP	// Set SP to g0 stack
-
-noswitch:
-	SUBQ	$16, SP		// Space for results
-	ANDQ	$~15, SP	// Align for C code
-
-	MOVL	$1, DI // CLOCK_MONOTONIC
-	LEAQ	0(SP), SI
-	MOVQ	runtime·vdsoClockgettimeSym(SB), AX
-	CMPQ	AX, $0
-	JEQ	fallback
-	CALL	AX
-ret:
-	MOVQ	0(SP), AX	// sec
-	MOVQ	8(SP), DX	// nsec
-	MOVQ	R12, SP		// Restore real SP
-	// Restore vdsoPC, vdsoSP
-	// We don't worry about being signaled between the two stores.
-	// If we are not in a signal handler, we'll restore vdsoSP to 0,
-	// and no one will care about vdsoPC. If we are in a signal handler,
-	// we cannot receive another signal.
-	MOVQ	8(SP), CX
-	MOVQ	CX, m_vdsoSP(BX)
-	MOVQ	0(SP), CX
-	MOVQ	CX, m_vdsoPC(BX)
-	// sec is in AX, nsec in DX
-	// return nsec in AX
-	IMULQ	$1000000000, AX
-	ADDQ	DX, AX
-	MOVQ	AX, ret+0(FP)
-	RET
-fallback:
-	MOVQ	$SYS_clock_gettime, AX
-	SYSCALL
-	JMP	ret
-
-TEXT runtime·rtsigprocmask(SB),NOSPLIT,$0-28
-	MOVL	how+0(FP), DI
-	MOVQ	new+8(FP), SI
-	MOVQ	old+16(FP), DX
-	MOVL	size+24(FP), R10
-	MOVL	$SYS_rt_sigprocmask, AX
-	SYSCALL
-	CMPQ	AX, $0xfffffffffffff001
-	JLS	2(PC)
-	MOVL	$0xf1, 0xf1  // crash
-	RET
-
-TEXT runtime·rt_sigaction(SB),NOSPLIT,$0-36
-	MOVQ	sig+0(FP), DI
-	MOVQ	new+8(FP), SI
-	MOVQ	old+16(FP), DX
-	MOVQ	size+24(FP), R10
-	MOVL	$SYS_rt_sigaction, AX
-	SYSCALL
-	MOVL	AX, ret+32(FP)
-	RET
-
-// Call the function stored in _cgo_sigaction using the GCC calling convention.
-TEXT runtime·callCgoSigaction(SB),NOSPLIT,$16
-	MOVQ	sig+0(FP), DI
-	MOVQ	new+8(FP), SI
-	MOVQ	old+16(FP), DX
-	MOVQ	_cgo_sigaction(SB), AX
-	MOVQ	SP, BX	// callee-saved
-	ANDQ	$~15, SP	// alignment as per amd64 psABI
-	CALL	AX
-	MOVQ	BX, SP
-	MOVL	AX, ret+24(FP)
-	RET
-
-TEXT runtime·sigfwd(SB),NOSPLIT,$0-32
-	MOVQ	fn+0(FP),    AX
-	MOVL	sig+8(FP),   DI
-	MOVQ	info+16(FP), SI
-	MOVQ	ctx+24(FP),  DX
-	PUSHQ	BP
-	MOVQ	SP, BP
-	ANDQ	$~15, SP     // alignment for x86_64 ABI
-	CALL	AX
-	MOVQ	BP, SP
-	POPQ	BP
-	RET
-
-// Called using C ABI.
-TEXT runtime·sigtramp(SB),NOSPLIT,$0
-	// Transition from C ABI to Go ABI.
-	PUSH_REGS_HOST_TO_ABI0()
-
-	// Call into the Go signal handler
-	NOP	SP		// disable vet stack checking
-        ADJSP   $24
-	MOVQ	DI, 0(SP)	// sig
-	MOVQ	SI, 8(SP)	// info
-	MOVQ	DX, 16(SP)	// ctx
-	CALL	·sigtrampgo(SB)
-	ADJSP	$-24
-
-        POP_REGS_HOST_TO_ABI0()
-	RET
-
-// Called using C ABI.
-TEXT runtime·sigprofNonGoWrapper<>(SB),NOSPLIT,$0
-	// Transition from C ABI to Go ABI.
-	PUSH_REGS_HOST_TO_ABI0()
-
-	// Call into the Go signal handler
-	NOP	SP		// disable vet stack checking
-	ADJSP	$24
-	MOVL	DI, 0(SP)	// sig
-	MOVQ	SI, 8(SP)	// info
-	MOVQ	DX, 16(SP)	// ctx
-	CALL	·sigprofNonGo(SB)
-	ADJSP	$-24
-
-	POP_REGS_HOST_TO_ABI0()
-	RET
-
-// Used instead of sigtramp in programs that use cgo.
-// Arguments from kernel are in DI, SI, DX.
-TEXT runtime·cgoSigtramp(SB),NOSPLIT,$0
-	// If no traceback function, do usual sigtramp.
-	MOVQ	runtime·cgoTraceback(SB), AX
-	TESTQ	AX, AX
-	JZ	sigtramp
-
-	// If no traceback support function, which means that
-	// runtime/cgo was not linked in, do usual sigtramp.
-	MOVQ	_cgo_callers(SB), AX
-	TESTQ	AX, AX
-	JZ	sigtramp
-
-	// Figure out if we are currently in a cgo call.
-	// If not, just do usual sigtramp.
-	get_tls(CX)
-	MOVQ	g(CX),AX
-	TESTQ	AX, AX
-	JZ	sigtrampnog     // g == nil
-	MOVQ	g_m(AX), AX
-	TESTQ	AX, AX
-	JZ	sigtramp        // g.m == nil
-	MOVL	m_ncgo(AX), CX
-	TESTL	CX, CX
-	JZ	sigtramp        // g.m.ncgo == 0
-	MOVQ	m_curg(AX), CX
-	TESTQ	CX, CX
-	JZ	sigtramp        // g.m.curg == nil
-	MOVQ	g_syscallsp(CX), CX
-	TESTQ	CX, CX
-	JZ	sigtramp        // g.m.curg.syscallsp == 0
-	MOVQ	m_cgoCallers(AX), R8
-	TESTQ	R8, R8
-	JZ	sigtramp        // g.m.cgoCallers == nil
-	MOVL	m_cgoCallersUse(AX), CX
-	TESTL	CX, CX
-	JNZ	sigtramp	// g.m.cgoCallersUse != 0
-
-	// Jump to a function in runtime/cgo.
-	// That function, written in C, will call the user's traceback
-	// function with proper unwind info, and will then call back here.
-	// The first three arguments, and the fifth, are already in registers.
-	// Set the two remaining arguments now.
-	MOVQ	runtime·cgoTraceback(SB), CX
-	MOVQ	$runtime·sigtramp(SB), R9
-	MOVQ	_cgo_callers(SB), AX
-	JMP	AX
-
-sigtramp:
-	JMP	runtime·sigtramp(SB)
-
-sigtrampnog:
-	// Signal arrived on a non-Go thread. If this is SIGPROF, get a
-	// stack trace.
-	CMPL	DI, $27 // 27 == SIGPROF
-	JNZ	sigtramp
-
-	// Lock sigprofCallersUse.
-	MOVL	$0, AX
-	MOVL	$1, CX
-	MOVQ	$runtime·sigprofCallersUse(SB), R11
-	LOCK
-	CMPXCHGL	CX, 0(R11)
-	JNZ	sigtramp  // Skip stack trace if already locked.
-
-	// Jump to the traceback function in runtime/cgo.
-	// It will call back to sigprofNonGo, via sigprofNonGoWrapper, to convert
-	// the arguments to the Go calling convention.
-	// First three arguments to traceback function are in registers already.
-	MOVQ	runtime·cgoTraceback(SB), CX
-	MOVQ	$runtime·sigprofCallers(SB), R8
-	MOVQ	$runtime·sigprofNonGoWrapper<>(SB), R9
-	MOVQ	_cgo_callers(SB), AX
-	JMP	AX
-
-// For cgo unwinding to work, this function must look precisely like
-// the one in glibc.  The glibc source code is:
-// https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/unix/sysv/linux/x86_64/sigaction.c
-// The code that cares about the precise instructions used is:
-// https://gcc.gnu.org/viewcvs/gcc/trunk/libgcc/config/i386/linux-unwind.h?revision=219188&view=markup
-TEXT runtime·sigreturn(SB),NOSPLIT,$0
-	MOVQ	$SYS_rt_sigreturn, AX
-	SYSCALL
-	INT $3	// not reached
-
-TEXT runtime·sysMmap(SB),NOSPLIT,$0
-	MOVQ	addr+0(FP), DI
-	MOVQ	n+8(FP), SI
-	MOVL	prot+16(FP), DX
-	MOVL	flags+20(FP), R10
-	MOVL	fd+24(FP), R8
-	MOVL	off+28(FP), R9
-
-	MOVL	$SYS_mmap, AX
-	SYSCALL
-	CMPQ	AX, $0xfffffffffffff001
-	JLS	ok
-	NOTQ	AX
-	INCQ	AX
-	MOVQ	$0, p+32(FP)
-	MOVQ	AX, err+40(FP)
-	RET
-ok:
-	MOVQ	AX, p+32(FP)
-	MOVQ	$0, err+40(FP)
-	RET
-
-// Call the function stored in _cgo_mmap using the GCC calling convention.
-// This must be called on the system stack.
-TEXT runtime·callCgoMmap(SB),NOSPLIT,$16
-	MOVQ	addr+0(FP), DI
-	MOVQ	n+8(FP), SI
-	MOVL	prot+16(FP), DX
-	MOVL	flags+20(FP), CX
-	MOVL	fd+24(FP), R8
-	MOVL	off+28(FP), R9
-	MOVQ	_cgo_mmap(SB), AX
-	MOVQ	SP, BX
-	ANDQ	$~15, SP	// alignment as per amd64 psABI
-	MOVQ	BX, 0(SP)
-	CALL	AX
-	MOVQ	0(SP), SP
-	MOVQ	AX, ret+32(FP)
-	RET
-
-TEXT runtime·sysMunmap(SB),NOSPLIT,$0
-	MOVQ	addr+0(FP), DI
-	MOVQ	n+8(FP), SI
-	MOVQ	$SYS_munmap, AX
-	SYSCALL
-	CMPQ	AX, $0xfffffffffffff001
-	JLS	2(PC)
-	MOVL	$0xf1, 0xf1  // crash
-	RET
-
-// Call the function stored in _cgo_munmap using the GCC calling convention.
-// This must be called on the system stack.
-TEXT runtime·callCgoMunmap(SB),NOSPLIT,$16-16
-	MOVQ	addr+0(FP), DI
-	MOVQ	n+8(FP), SI
-	MOVQ	_cgo_munmap(SB), AX
-	MOVQ	SP, BX
-	ANDQ	$~15, SP	// alignment as per amd64 psABI
-	MOVQ	BX, 0(SP)
-	CALL	AX
-	MOVQ	0(SP), SP
-	RET
-
-TEXT runtime·madvise(SB),NOSPLIT,$0
-	MOVQ	addr+0(FP), DI
-	MOVQ	n+8(FP), SI
-	MOVL	flags+16(FP), DX
-	MOVQ	$SYS_madvise, AX
-	SYSCALL
-	MOVL	AX, ret+24(FP)
-	RET
-
-// int64 futex(int32 *uaddr, int32 op, int32 val,
-//	struct timespec *timeout, int32 *uaddr2, int32 val2);
-TEXT runtime·futex(SB),NOSPLIT,$0
-	MOVQ	addr+0(FP), DI
-	MOVL	op+8(FP), SI
-	MOVL	val+12(FP), DX
-	MOVQ	ts+16(FP), R10
-	MOVQ	addr2+24(FP), R8
-	MOVL	val3+32(FP), R9
-	MOVL	$SYS_futex, AX
-	SYSCALL
-	MOVL	AX, ret+40(FP)
-	RET
-
-// int32 clone(int32 flags, void *stk, M *mp, G *gp, void (*fn)(void));
-TEXT runtime·clone(SB),NOSPLIT,$0
-	MOVL	flags+0(FP), DI
-	MOVQ	stk+8(FP), SI
-	MOVQ	$0, DX
-	MOVQ	$0, R10
-	MOVQ    $0, R8
-	// Copy mp, gp, fn off parent stack for use by child.
-	// Careful: Linux system call clobbers CX and R11.
-	MOVQ	mp+16(FP), R13
-	MOVQ	gp+24(FP), R9
-	MOVQ	fn+32(FP), R12
-	CMPQ	R13, $0    // m
-	JEQ	nog1
-	CMPQ	R9, $0    // g
-	JEQ	nog1
-	LEAQ	m_tls(R13), R8
-#ifdef GOOS_android
-	// Android stores the TLS offset in runtime·tls_g.
-	SUBQ	runtime·tls_g(SB), R8
-#else
-	ADDQ	$8, R8	// ELF wants to use -8(FS)
-#endif
-	ORQ 	$0x00080000, DI //add flag CLONE_SETTLS(0x00080000) to call clone
-nog1:
-	MOVL	$SYS_clone, AX
-	SYSCALL
-
-	// In parent, return.
-	CMPQ	AX, $0
-	JEQ	3(PC)
-	MOVL	AX, ret+40(FP)
-	RET
-
-	// In child, on new stack.
-	MOVQ	SI, SP
-
-	// If g or m are nil, skip Go-related setup.
-	CMPQ	R13, $0    // m
-	JEQ	nog2
-	CMPQ	R9, $0    // g
-	JEQ	nog2
-
-	// Initialize m->procid to Linux tid
-	MOVL	$SYS_gettid, AX
-	SYSCALL
-	MOVQ	AX, m_procid(R13)
-
-	// In child, set up new stack
-	get_tls(CX)
-	MOVQ	R13, g_m(R9)
-	MOVQ	R9, g(CX)
-	MOVQ	R9, R14 // set g register
-	CALL	runtime·stackcheck(SB)
-
-nog2:
-	// Call fn. This is the PC of an ABI0 function.
-	CALL	R12
-
-	// It shouldn't return. If it does, exit that thread.
-	MOVL	$111, DI
-	MOVL	$SYS_exit, AX
-	SYSCALL
-	JMP	-3(PC)	// keep exiting
-
-TEXT runtime·sigaltstack(SB),NOSPLIT,$-8
-	MOVQ	new+0(FP), DI
-	MOVQ	old+8(FP), SI
-	MOVQ	$SYS_sigaltstack, AX
-	SYSCALL
-	CMPQ	AX, $0xfffffffffffff001
-	JLS	2(PC)
-	MOVL	$0xf1, 0xf1  // crash
-	RET
-
-// set tls base to DI
-TEXT runtime·settls(SB),NOSPLIT,$32
-#ifdef GOOS_android
-	// Android stores the TLS offset in runtime·tls_g.
-	SUBQ	runtime·tls_g(SB), DI
-#else
-	ADDQ	$8, DI	// ELF wants to use -8(FS)
-#endif
-	MOVQ	DI, SI
-	MOVQ	$0x1002, DI	// ARCH_SET_FS
-	MOVQ	$SYS_arch_prctl, AX
-	SYSCALL
-	CMPQ	AX, $0xfffffffffffff001
-	JLS	2(PC)
-	MOVL	$0xf1, 0xf1  // crash
-	RET
-
-TEXT runtime·osyield(SB),NOSPLIT,$0
-	MOVL	$SYS_sched_yield, AX
-	SYSCALL
-	RET
-
-TEXT runtime·sched_getaffinity(SB),NOSPLIT,$0
-	MOVQ	pid+0(FP), DI
-	MOVQ	len+8(FP), SI
-	MOVQ	buf+16(FP), DX
-	MOVL	$SYS_sched_getaffinity, AX
-	SYSCALL
-	MOVL	AX, ret+24(FP)
-	RET
-
-// int32 runtime·epollcreate(int32 size);
-TEXT runtime·epollcreate(SB),NOSPLIT,$0
-	MOVL    size+0(FP), DI
-	MOVL    $SYS_epoll_create, AX
-	SYSCALL
-	MOVL	AX, ret+8(FP)
-	RET
-
-// int32 runtime·epollcreate1(int32 flags);
-TEXT runtime·epollcreate1(SB),NOSPLIT,$0
-	MOVL	flags+0(FP), DI
-	MOVL	$SYS_epoll_create1, AX
-	SYSCALL
-	MOVL	AX, ret+8(FP)
-	RET
-
-// func epollctl(epfd, op, fd int32, ev *epollEvent) int
-TEXT runtime·epollctl(SB),NOSPLIT,$0
-	MOVL	epfd+0(FP), DI
-	MOVL	op+4(FP), SI
-	MOVL	fd+8(FP), DX
-	MOVQ	ev+16(FP), R10
-	MOVL	$SYS_epoll_ctl, AX
-	SYSCALL
-	MOVL	AX, ret+24(FP)
-	RET
-
-// int32 runtime·epollwait(int32 epfd, EpollEvent *ev, int32 nev, int32 timeout);
-TEXT runtime·epollwait(SB),NOSPLIT,$0
-	// This uses pwait instead of wait, because Android O blocks wait.
-	MOVL	epfd+0(FP), DI
-	MOVQ	ev+8(FP), SI
-	MOVL	nev+16(FP), DX
-	MOVL	timeout+20(FP), R10
-	MOVQ	$0, R8
-	MOVL	$SYS_epoll_pwait, AX
-	SYSCALL
-	MOVL	AX, ret+24(FP)
-	RET
-
-// void runtime·closeonexec(int32 fd);
-TEXT runtime·closeonexec(SB),NOSPLIT,$0
-	MOVL    fd+0(FP), DI  // fd
-	MOVQ    $2, SI  // F_SETFD
-	MOVQ    $1, DX  // FD_CLOEXEC
-	MOVL	$SYS_fcntl, AX
-	SYSCALL
-	RET
-
-// func runtime·setNonblock(int32 fd)
-TEXT runtime·setNonblock(SB),NOSPLIT,$0-4
-	MOVL    fd+0(FP), DI  // fd
-	MOVQ    $3, SI  // F_GETFL
-	MOVQ    $0, DX
-	MOVL	$SYS_fcntl, AX
-	SYSCALL
-	MOVL	fd+0(FP), DI // fd
-	MOVQ	$4, SI // F_SETFL
-	MOVQ	$0x800, DX // O_NONBLOCK
-	ORL	AX, DX
-	MOVL	$SYS_fcntl, AX
-	SYSCALL
-	RET
-
-// int access(const char *name, int mode)
-TEXT runtime·access(SB),NOSPLIT,$0
-	// This uses faccessat instead of access, because Android O blocks access.
-	MOVL	$AT_FDCWD, DI // AT_FDCWD, so this acts like access
-	MOVQ	name+0(FP), SI
-	MOVL	mode+8(FP), DX
-	MOVL	$0, R10
-	MOVL	$SYS_faccessat, AX
-	SYSCALL
-	MOVL	AX, ret+16(FP)
-	RET
-
-// int connect(int fd, const struct sockaddr *addr, socklen_t addrlen)
-TEXT runtime·connect(SB),NOSPLIT,$0-28
-	MOVL	fd+0(FP), DI
-	MOVQ	addr+8(FP), SI
-	MOVL	len+16(FP), DX
-	MOVL	$SYS_connect, AX
-	SYSCALL
-	MOVL	AX, ret+24(FP)
-	RET
-
-// int socket(int domain, int type, int protocol)
-TEXT runtime·socket(SB),NOSPLIT,$0-20
-	MOVL	domain+0(FP), DI
-	MOVL	typ+4(FP), SI
-	MOVL	prot+8(FP), DX
-	MOVL	$SYS_socket, AX
-	SYSCALL
-	MOVL	AX, ret+16(FP)
-	RET
-
-// func sbrk0() uintptr
-TEXT runtime·sbrk0(SB),NOSPLIT,$0-8
-	// Implemented as brk(NULL).
-	MOVQ	$0, DI
-	MOVL	$SYS_brk, AX
-	SYSCALL
-	MOVQ	AX, ret+0(FP)
-	RET
diff --git a/contrib/go/_std_1.18/src/runtime/time.go b/contrib/go/_std_1.18/src/runtime/time.go
deleted file mode 100644
index a9ad620776..0000000000
--- a/contrib/go/_std_1.18/src/runtime/time.go
+++ /dev/null
@@ -1,1128 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Time-related runtime and pieces of package time.
-
-package runtime
-
-import (
-	"internal/abi"
-	"runtime/internal/atomic"
-	"runtime/internal/sys"
-	"unsafe"
-)
-
-// Package time knows the layout of this structure.
-// If this struct changes, adjust ../time/sleep.go:/runtimeTimer.
-type timer struct {
-	// If this timer is on a heap, which P's heap it is on.
-	// puintptr rather than *p to match uintptr in the versions
-	// of this struct defined in other packages.
-	pp puintptr
-
-	// Timer wakes up at when, and then at when+period, ... (period > 0 only)
-	// each time calling f(arg, now) in the timer goroutine, so f must be
-	// a well-behaved function and not block.
-	//
-	// when must be positive on an active timer.
-	when   int64
-	period int64
-	f      func(any, uintptr)
-	arg    any
-	seq    uintptr
-
-	// What to set the when field to in timerModifiedXX status.
-	nextwhen int64
-
-	// The status field holds one of the values below.
-	status uint32
-}
-
-// Code outside this file has to be careful in using a timer value.
-//
-// The pp, status, and nextwhen fields may only be used by code in this file.
-//
-// Code that creates a new timer value can set the when, period, f,
-// arg, and seq fields.
-// A new timer value may be passed to addtimer (called by time.startTimer).
-// After doing that no fields may be touched.
-//
-// An active timer (one that has been passed to addtimer) may be
-// passed to deltimer (time.stopTimer), after which it is no longer an
-// active timer. It is an inactive timer.
-// In an inactive timer the period, f, arg, and seq fields may be modified,
-// but not the when field.
-// It's OK to just drop an inactive timer and let the GC collect it.
-// It's not OK to pass an inactive timer to addtimer.
-// Only newly allocated timer values may be passed to addtimer.
-//
-// An active timer may be passed to modtimer. No fields may be touched.
-// It remains an active timer.
-//
-// An inactive timer may be passed to resettimer to turn into an
-// active timer with an updated when field.
-// It's OK to pass a newly allocated timer value to resettimer.
-//
-// Timer operations are addtimer, deltimer, modtimer, resettimer,
-// cleantimers, adjusttimers, and runtimer.
-//
-// We don't permit calling addtimer/deltimer/modtimer/resettimer simultaneously,
-// but adjusttimers and runtimer can be called at the same time as any of those.
-//
-// Active timers live in heaps attached to P, in the timers field.
-// Inactive timers live there too temporarily, until they are removed.
-//
-// addtimer:
-//   timerNoStatus   -> timerWaiting
-//   anything else   -> panic: invalid value
-// deltimer:
-//   timerWaiting         -> timerModifying -> timerDeleted
-//   timerModifiedEarlier -> timerModifying -> timerDeleted
-//   timerModifiedLater   -> timerModifying -> timerDeleted
-//   timerNoStatus        -> do nothing
-//   timerDeleted         -> do nothing
-//   timerRemoving        -> do nothing
-//   timerRemoved         -> do nothing
-//   timerRunning         -> wait until status changes
-//   timerMoving          -> wait until status changes
-//   timerModifying       -> wait until status changes
-// modtimer:
-//   timerWaiting    -> timerModifying -> timerModifiedXX
-//   timerModifiedXX -> timerModifying -> timerModifiedYY
-//   timerNoStatus   -> timerModifying -> timerWaiting
-//   timerRemoved    -> timerModifying -> timerWaiting
-//   timerDeleted    -> timerModifying -> timerModifiedXX
-//   timerRunning    -> wait until status changes
-//   timerMoving     -> wait until status changes
-//   timerRemoving   -> wait until status changes
-//   timerModifying  -> wait until status changes
-// cleantimers (looks in P's timer heap):
-//   timerDeleted    -> timerRemoving -> timerRemoved
-//   timerModifiedXX -> timerMoving -> timerWaiting
-// adjusttimers (looks in P's timer heap):
-//   timerDeleted    -> timerRemoving -> timerRemoved
-//   timerModifiedXX -> timerMoving -> timerWaiting
-// runtimer (looks in P's timer heap):
-//   timerNoStatus   -> panic: uninitialized timer
-//   timerWaiting    -> timerWaiting or
-//   timerWaiting    -> timerRunning -> timerNoStatus or
-//   timerWaiting    -> timerRunning -> timerWaiting
-//   timerModifying  -> wait until status changes
-//   timerModifiedXX -> timerMoving -> timerWaiting
-//   timerDeleted    -> timerRemoving -> timerRemoved
-//   timerRunning    -> panic: concurrent runtimer calls
-//   timerRemoved    -> panic: inconsistent timer heap
-//   timerRemoving   -> panic: inconsistent timer heap
-//   timerMoving     -> panic: inconsistent timer heap
-
-// Values for the timer status field.
-const (
-	// Timer has no status set yet.
-	timerNoStatus = iota
-
-	// Waiting for timer to fire.
-	// The timer is in some P's heap.
-	timerWaiting
-
-	// Running the timer function.
-	// A timer will only have this status briefly.
-	timerRunning
-
-	// The timer is deleted and should be removed.
-	// It should not be run, but it is still in some P's heap.
-	timerDeleted
-
-	// The timer is being removed.
-	// The timer will only have this status briefly.
-	timerRemoving
-
-	// The timer has been stopped.
-	// It is not in any P's heap.
-	timerRemoved
-
-	// The timer is being modified.
-	// The timer will only have this status briefly.
-	timerModifying
-
-	// The timer has been modified to an earlier time.
-	// The new when value is in the nextwhen field.
-	// The timer is in some P's heap, possibly in the wrong place.
-	timerModifiedEarlier
-
-	// The timer has been modified to the same or a later time.
-	// The new when value is in the nextwhen field.
-	// The timer is in some P's heap, possibly in the wrong place.
-	timerModifiedLater
-
-	// The timer has been modified and is being moved.
-	// The timer will only have this status briefly.
-	timerMoving
-)
-
-// maxWhen is the maximum value for timer's when field.
-const maxWhen = 1<<63 - 1
-
-// verifyTimers can be set to true to add debugging checks that the
-// timer heaps are valid.
-const verifyTimers = false
-
-// Package time APIs.
-// Godoc uses the comments in package time, not these.
-
-// time.now is implemented in assembly.
-
-// timeSleep puts the current goroutine to sleep for at least ns nanoseconds.
-//go:linkname timeSleep time.Sleep
-func timeSleep(ns int64) {
-	if ns <= 0 {
-		return
-	}
-
-	gp := getg()
-	t := gp.timer
-	if t == nil {
-		t = new(timer)
-		gp.timer = t
-	}
-	t.f = goroutineReady
-	t.arg = gp
-	t.nextwhen = nanotime() + ns
-	if t.nextwhen < 0 { // check for overflow.
-		t.nextwhen = maxWhen
-	}
-	gopark(resetForSleep, unsafe.Pointer(t), waitReasonSleep, traceEvGoSleep, 1)
-}
-
-// resetForSleep is called after the goroutine is parked for timeSleep.
-// We can't call resettimer in timeSleep itself because if this is a short
-// sleep and there are many goroutines then the P can wind up running the
-// timer function, goroutineReady, before the goroutine has been parked.
-func resetForSleep(gp *g, ut unsafe.Pointer) bool {
-	t := (*timer)(ut)
-	resettimer(t, t.nextwhen)
-	return true
-}
-
-// startTimer adds t to the timer heap.
-//go:linkname startTimer time.startTimer
-func startTimer(t *timer) {
-	if raceenabled {
-		racerelease(unsafe.Pointer(t))
-	}
-	addtimer(t)
-}
-
-// stopTimer stops a timer.
-// It reports whether t was stopped before being run.
-//go:linkname stopTimer time.stopTimer
-func stopTimer(t *timer) bool {
-	return deltimer(t)
-}
-
-// resetTimer resets an inactive timer, adding it to the heap.
-//go:linkname resetTimer time.resetTimer
-// Reports whether the timer was modified before it was run.
-func resetTimer(t *timer, when int64) bool {
-	if raceenabled {
-		racerelease(unsafe.Pointer(t))
-	}
-	return resettimer(t, when)
-}
-
-// modTimer modifies an existing timer.
-//go:linkname modTimer time.modTimer
-func modTimer(t *timer, when, period int64, f func(any, uintptr), arg any, seq uintptr) {
-	modtimer(t, when, period, f, arg, seq)
-}
-
-// Go runtime.
-
-// Ready the goroutine arg.
-func goroutineReady(arg any, seq uintptr) {
-	goready(arg.(*g), 0)
-}
-
-// addtimer adds a timer to the current P.
-// This should only be called with a newly created timer.
-// That avoids the risk of changing the when field of a timer in some P's heap,
-// which could cause the heap to become unsorted.
-func addtimer(t *timer) {
-	// when must be positive. A negative value will cause runtimer to
-	// overflow during its delta calculation and never expire other runtime
-	// timers. Zero will cause checkTimers to fail to notice the timer.
-	if t.when <= 0 {
-		throw("timer when must be positive")
-	}
-	if t.period < 0 {
-		throw("timer period must be non-negative")
-	}
-	if t.status != timerNoStatus {
-		throw("addtimer called with initialized timer")
-	}
-	t.status = timerWaiting
-
-	when := t.when
-
-	// Disable preemption while using pp to avoid changing another P's heap.
-	mp := acquirem()
-
-	pp := getg().m.p.ptr()
-	lock(&pp.timersLock)
-	cleantimers(pp)
-	doaddtimer(pp, t)
-	unlock(&pp.timersLock)
-
-	wakeNetPoller(when)
-
-	releasem(mp)
-}
-
-// doaddtimer adds t to the current P's heap.
-// The caller must have locked the timers for pp.
-func doaddtimer(pp *p, t *timer) {
-	// Timers rely on the network poller, so make sure the poller
-	// has started.
-	if netpollInited == 0 {
-		netpollGenericInit()
-	}
-
-	if t.pp != 0 {
-		throw("doaddtimer: P already set in timer")
-	}
-	t.pp.set(pp)
-	i := len(pp.timers)
-	pp.timers = append(pp.timers, t)
-	siftupTimer(pp.timers, i)
-	if t == pp.timers[0] {
-		atomic.Store64(&pp.timer0When, uint64(t.when))
-	}
-	atomic.Xadd(&pp.numTimers, 1)
-}
-
-// deltimer deletes the timer t. It may be on some other P, so we can't
-// actually remove it from the timers heap. We can only mark it as deleted.
-// It will be removed in due course by the P whose heap it is on.
-// Reports whether the timer was removed before it was run.
-func deltimer(t *timer) bool {
-	for {
-		switch s := atomic.Load(&t.status); s {
-		case timerWaiting, timerModifiedLater:
-			// Prevent preemption while the timer is in timerModifying.
-			// This could lead to a self-deadlock. See #38070.
-			mp := acquirem()
-			if atomic.Cas(&t.status, s, timerModifying) {
-				// Must fetch t.pp before changing status,
-				// as cleantimers in another goroutine
-				// can clear t.pp of a timerDeleted timer.
-				tpp := t.pp.ptr()
-				if !atomic.Cas(&t.status, timerModifying, timerDeleted) {
-					badTimer()
-				}
-				releasem(mp)
-				atomic.Xadd(&tpp.deletedTimers, 1)
-				// Timer was not yet run.
-				return true
-			} else {
-				releasem(mp)
-			}
-		case timerModifiedEarlier:
-			// Prevent preemption while the timer is in timerModifying.
-			// This could lead to a self-deadlock. See #38070.
-			mp := acquirem()
-			if atomic.Cas(&t.status, s, timerModifying) {
-				// Must fetch t.pp before setting status
-				// to timerDeleted.
-				tpp := t.pp.ptr()
-				if !atomic.Cas(&t.status, timerModifying, timerDeleted) {
-					badTimer()
-				}
-				releasem(mp)
-				atomic.Xadd(&tpp.deletedTimers, 1)
-				// Timer was not yet run.
-				return true
-			} else {
-				releasem(mp)
-			}
-		case timerDeleted, timerRemoving, timerRemoved:
-			// Timer was already run.
-			return false
-		case timerRunning, timerMoving:
-			// The timer is being run or moved, by a different P.
-			// Wait for it to complete.
-			osyield()
-		case timerNoStatus:
-			// Removing timer that was never added or
-			// has already been run. Also see issue 21874.
-			return false
-		case timerModifying:
-			// Simultaneous calls to deltimer and modtimer.
-			// Wait for the other call to complete.
-			osyield()
-		default:
-			badTimer()
-		}
-	}
-}
-
-// dodeltimer removes timer i from the current P's heap.
-// We are locked on the P when this is called.
-// It returns the smallest changed index in pp.timers.
-// The caller must have locked the timers for pp.
-func dodeltimer(pp *p, i int) int {
-	if t := pp.timers[i]; t.pp.ptr() != pp {
-		throw("dodeltimer: wrong P")
-	} else {
-		t.pp = 0
-	}
-	last := len(pp.timers) - 1
-	if i != last {
-		pp.timers[i] = pp.timers[last]
-	}
-	pp.timers[last] = nil
-	pp.timers = pp.timers[:last]
-	smallestChanged := i
-	if i != last {
-		// Moving to i may have moved the last timer to a new parent,
-		// so sift up to preserve the heap guarantee.
-		smallestChanged = siftupTimer(pp.timers, i)
-		siftdownTimer(pp.timers, i)
-	}
-	if i == 0 {
-		updateTimer0When(pp)
-	}
-	atomic.Xadd(&pp.numTimers, -1)
-	return smallestChanged
-}
-
-// dodeltimer0 removes timer 0 from the current P's heap.
-// We are locked on the P when this is called.
-// It reports whether it saw no problems due to races.
-// The caller must have locked the timers for pp.
-func dodeltimer0(pp *p) {
-	if t := pp.timers[0]; t.pp.ptr() != pp {
-		throw("dodeltimer0: wrong P")
-	} else {
-		t.pp = 0
-	}
-	last := len(pp.timers) - 1
-	if last > 0 {
-		pp.timers[0] = pp.timers[last]
-	}
-	pp.timers[last] = nil
-	pp.timers = pp.timers[:last]
-	if last > 0 {
-		siftdownTimer(pp.timers, 0)
-	}
-	updateTimer0When(pp)
-	atomic.Xadd(&pp.numTimers, -1)
-}
-
-// modtimer modifies an existing timer.
-// This is called by the netpoll code or time.Ticker.Reset or time.Timer.Reset.
-// Reports whether the timer was modified before it was run.
-func modtimer(t *timer, when, period int64, f func(any, uintptr), arg any, seq uintptr) bool {
-	if when <= 0 {
-		throw("timer when must be positive")
-	}
-	if period < 0 {
-		throw("timer period must be non-negative")
-	}
-
-	status := uint32(timerNoStatus)
-	wasRemoved := false
-	var pending bool
-	var mp *m
-loop:
-	for {
-		switch status = atomic.Load(&t.status); status {
-		case timerWaiting, timerModifiedEarlier, timerModifiedLater:
-			// Prevent preemption while the timer is in timerModifying.
-			// This could lead to a self-deadlock. See #38070.
-			mp = acquirem()
-			if atomic.Cas(&t.status, status, timerModifying) {
-				pending = true // timer not yet run
-				break loop
-			}
-			releasem(mp)
-		case timerNoStatus, timerRemoved:
-			// Prevent preemption while the timer is in timerModifying.
-			// This could lead to a self-deadlock. See #38070.
-			mp = acquirem()
-
-			// Timer was already run and t is no longer in a heap.
-			// Act like addtimer.
-			if atomic.Cas(&t.status, status, timerModifying) {
-				wasRemoved = true
-				pending = false // timer already run or stopped
-				break loop
-			}
-			releasem(mp)
-		case timerDeleted:
-			// Prevent preemption while the timer is in timerModifying.
-			// This could lead to a self-deadlock. See #38070.
-			mp = acquirem()
-			if atomic.Cas(&t.status, status, timerModifying) {
-				atomic.Xadd(&t.pp.ptr().deletedTimers, -1)
-				pending = false // timer already stopped
-				break loop
-			}
-			releasem(mp)
-		case timerRunning, timerRemoving, timerMoving:
-			// The timer is being run or moved, by a different P.
-			// Wait for it to complete.
-			osyield()
-		case timerModifying:
-			// Multiple simultaneous calls to modtimer.
-			// Wait for the other call to complete.
-			osyield()
-		default:
-			badTimer()
-		}
-	}
-
-	t.period = period
-	t.f = f
-	t.arg = arg
-	t.seq = seq
-
-	if wasRemoved {
-		t.when = when
-		pp := getg().m.p.ptr()
-		lock(&pp.timersLock)
-		doaddtimer(pp, t)
-		unlock(&pp.timersLock)
-		if !atomic.Cas(&t.status, timerModifying, timerWaiting) {
-			badTimer()
-		}
-		releasem(mp)
-		wakeNetPoller(when)
-	} else {
-		// The timer is in some other P's heap, so we can't change
-		// the when field. If we did, the other P's heap would
-		// be out of order. So we put the new when value in the
-		// nextwhen field, and let the other P set the when field
-		// when it is prepared to resort the heap.
-		t.nextwhen = when
-
-		newStatus := uint32(timerModifiedLater)
-		if when < t.when {
-			newStatus = timerModifiedEarlier
-		}
-
-		tpp := t.pp.ptr()
-
-		if newStatus == timerModifiedEarlier {
-			updateTimerModifiedEarliest(tpp, when)
-		}
-
-		// Set the new status of the timer.
-		if !atomic.Cas(&t.status, timerModifying, newStatus) {
-			badTimer()
-		}
-		releasem(mp)
-
-		// If the new status is earlier, wake up the poller.
-		if newStatus == timerModifiedEarlier {
-			wakeNetPoller(when)
-		}
-	}
-
-	return pending
-}
-
-// resettimer resets the time when a timer should fire.
-// If used for an inactive timer, the timer will become active.
-// This should be called instead of addtimer if the timer value has been,
-// or may have been, used previously.
-// Reports whether the timer was modified before it was run.
-func resettimer(t *timer, when int64) bool {
-	return modtimer(t, when, t.period, t.f, t.arg, t.seq)
-}
-
-// cleantimers cleans up the head of the timer queue. This speeds up
-// programs that create and delete timers; leaving them in the heap
-// slows down addtimer. Reports whether no timer problems were found.
-// The caller must have locked the timers for pp.
-func cleantimers(pp *p) {
-	gp := getg()
-	for {
-		if len(pp.timers) == 0 {
-			return
-		}
-
-		// This loop can theoretically run for a while, and because
-		// it is holding timersLock it cannot be preempted.
-		// If someone is trying to preempt us, just return.
-		// We can clean the timers later.
-		if gp.preemptStop {
-			return
-		}
-
-		t := pp.timers[0]
-		if t.pp.ptr() != pp {
-			throw("cleantimers: bad p")
-		}
-		switch s := atomic.Load(&t.status); s {
-		case timerDeleted:
-			if !atomic.Cas(&t.status, s, timerRemoving) {
-				continue
-			}
-			dodeltimer0(pp)
-			if !atomic.Cas(&t.status, timerRemoving, timerRemoved) {
-				badTimer()
-			}
-			atomic.Xadd(&pp.deletedTimers, -1)
-		case timerModifiedEarlier, timerModifiedLater:
-			if !atomic.Cas(&t.status, s, timerMoving) {
-				continue
-			}
-			// Now we can change the when field.
-			t.when = t.nextwhen
-			// Move t to the right position.
-			dodeltimer0(pp)
-			doaddtimer(pp, t)
-			if !atomic.Cas(&t.status, timerMoving, timerWaiting) {
-				badTimer()
-			}
-		default:
-			// Head of timers does not need adjustment.
-			return
-		}
-	}
-}
-
-// moveTimers moves a slice of timers to pp. The slice has been taken
-// from a different P.
-// This is currently called when the world is stopped, but the caller
-// is expected to have locked the timers for pp.
-func moveTimers(pp *p, timers []*timer) {
-	for _, t := range timers {
-	loop:
-		for {
-			switch s := atomic.Load(&t.status); s {
-			case timerWaiting:
-				if !atomic.Cas(&t.status, s, timerMoving) {
-					continue
-				}
-				t.pp = 0
-				doaddtimer(pp, t)
-				if !atomic.Cas(&t.status, timerMoving, timerWaiting) {
-					badTimer()
-				}
-				break loop
-			case timerModifiedEarlier, timerModifiedLater:
-				if !atomic.Cas(&t.status, s, timerMoving) {
-					continue
-				}
-				t.when = t.nextwhen
-				t.pp = 0
-				doaddtimer(pp, t)
-				if !atomic.Cas(&t.status, timerMoving, timerWaiting) {
-					badTimer()
-				}
-				break loop
-			case timerDeleted:
-				if !atomic.Cas(&t.status, s, timerRemoved) {
-					continue
-				}
-				t.pp = 0
-				// We no longer need this timer in the heap.
-				break loop
-			case timerModifying:
-				// Loop until the modification is complete.
-				osyield()
-			case timerNoStatus, timerRemoved:
-				// We should not see these status values in a timers heap.
-				badTimer()
-			case timerRunning, timerRemoving, timerMoving:
-				// Some other P thinks it owns this timer,
-				// which should not happen.
-				badTimer()
-			default:
-				badTimer()
-			}
-		}
-	}
-}
-
-// adjusttimers looks through the timers in the current P's heap for
-// any timers that have been modified to run earlier, and puts them in
-// the correct place in the heap. While looking for those timers,
-// it also moves timers that have been modified to run later,
-// and removes deleted timers. The caller must have locked the timers for pp.
-func adjusttimers(pp *p, now int64) {
-	// If we haven't yet reached the time of the first timerModifiedEarlier
-	// timer, don't do anything. This speeds up programs that adjust
-	// a lot of timers back and forth if the timers rarely expire.
-	// We'll postpone looking through all the adjusted timers until
-	// one would actually expire.
-	first := atomic.Load64(&pp.timerModifiedEarliest)
-	if first == 0 || int64(first) > now {
-		if verifyTimers {
-			verifyTimerHeap(pp)
-		}
-		return
-	}
-
-	// We are going to clear all timerModifiedEarlier timers.
-	atomic.Store64(&pp.timerModifiedEarliest, 0)
-
-	var moved []*timer
-	for i := 0; i < len(pp.timers); i++ {
-		t := pp.timers[i]
-		if t.pp.ptr() != pp {
-			throw("adjusttimers: bad p")
-		}
-		switch s := atomic.Load(&t.status); s {
-		case timerDeleted:
-			if atomic.Cas(&t.status, s, timerRemoving) {
-				changed := dodeltimer(pp, i)
-				if !atomic.Cas(&t.status, timerRemoving, timerRemoved) {
-					badTimer()
-				}
-				atomic.Xadd(&pp.deletedTimers, -1)
-				// Go back to the earliest changed heap entry.
-				// "- 1" because the loop will add 1.
-				i = changed - 1
-			}
-		case timerModifiedEarlier, timerModifiedLater:
-			if atomic.Cas(&t.status, s, timerMoving) {
-				// Now we can change the when field.
-				t.when = t.nextwhen
-				// Take t off the heap, and hold onto it.
-				// We don't add it back yet because the
-				// heap manipulation could cause our
-				// loop to skip some other timer.
-				changed := dodeltimer(pp, i)
-				moved = append(moved, t)
-				// Go back to the earliest changed heap entry.
-				// "- 1" because the loop will add 1.
-				i = changed - 1
-			}
-		case timerNoStatus, timerRunning, timerRemoving, timerRemoved, timerMoving:
-			badTimer()
-		case timerWaiting:
-			// OK, nothing to do.
-		case timerModifying:
-			// Check again after modification is complete.
-			osyield()
-			i--
-		default:
-			badTimer()
-		}
-	}
-
-	if len(moved) > 0 {
-		addAdjustedTimers(pp, moved)
-	}
-
-	if verifyTimers {
-		verifyTimerHeap(pp)
-	}
-}
-
-// addAdjustedTimers adds any timers we adjusted in adjusttimers
-// back to the timer heap.
-func addAdjustedTimers(pp *p, moved []*timer) {
-	for _, t := range moved {
-		doaddtimer(pp, t)
-		if !atomic.Cas(&t.status, timerMoving, timerWaiting) {
-			badTimer()
-		}
-	}
-}
-
-// nobarrierWakeTime looks at P's timers and returns the time when we
-// should wake up the netpoller. It returns 0 if there are no timers.
-// This function is invoked when dropping a P, and must run without
-// any write barriers.
-//go:nowritebarrierrec
-func nobarrierWakeTime(pp *p) int64 {
-	next := int64(atomic.Load64(&pp.timer0When))
-	nextAdj := int64(atomic.Load64(&pp.timerModifiedEarliest))
-	if next == 0 || (nextAdj != 0 && nextAdj < next) {
-		next = nextAdj
-	}
-	return next
-}
-
-// runtimer examines the first timer in timers. If it is ready based on now,
-// it runs the timer and removes or updates it.
-// Returns 0 if it ran a timer, -1 if there are no more timers, or the time
-// when the first timer should run.
-// The caller must have locked the timers for pp.
-// If a timer is run, this will temporarily unlock the timers.
-//go:systemstack
-func runtimer(pp *p, now int64) int64 {
-	for {
-		t := pp.timers[0]
-		if t.pp.ptr() != pp {
-			throw("runtimer: bad p")
-		}
-		switch s := atomic.Load(&t.status); s {
-		case timerWaiting:
-			if t.when > now {
-				// Not ready to run.
-				return t.when
-			}
-
-			if !atomic.Cas(&t.status, s, timerRunning) {
-				continue
-			}
-			// Note that runOneTimer may temporarily unlock
-			// pp.timersLock.
-			runOneTimer(pp, t, now)
-			return 0
-
-		case timerDeleted:
-			if !atomic.Cas(&t.status, s, timerRemoving) {
-				continue
-			}
-			dodeltimer0(pp)
-			if !atomic.Cas(&t.status, timerRemoving, timerRemoved) {
-				badTimer()
-			}
-			atomic.Xadd(&pp.deletedTimers, -1)
-			if len(pp.timers) == 0 {
-				return -1
-			}
-
-		case timerModifiedEarlier, timerModifiedLater:
-			if !atomic.Cas(&t.status, s, timerMoving) {
-				continue
-			}
-			t.when = t.nextwhen
-			dodeltimer0(pp)
-			doaddtimer(pp, t)
-			if !atomic.Cas(&t.status, timerMoving, timerWaiting) {
-				badTimer()
-			}
-
-		case timerModifying:
-			// Wait for modification to complete.
-			osyield()
-
-		case timerNoStatus, timerRemoved:
-			// Should not see a new or inactive timer on the heap.
-			badTimer()
-		case timerRunning, timerRemoving, timerMoving:
-			// These should only be set when timers are locked,
-			// and we didn't do it.
-			badTimer()
-		default:
-			badTimer()
-		}
-	}
-}
-
-// runOneTimer runs a single timer.
-// The caller must have locked the timers for pp.
-// This will temporarily unlock the timers while running the timer function.
-//go:systemstack
-func runOneTimer(pp *p, t *timer, now int64) {
-	if raceenabled {
-		ppcur := getg().m.p.ptr()
-		if ppcur.timerRaceCtx == 0 {
-			ppcur.timerRaceCtx = racegostart(abi.FuncPCABIInternal(runtimer) + sys.PCQuantum)
-		}
-		raceacquirectx(ppcur.timerRaceCtx, unsafe.Pointer(t))
-	}
-
-	f := t.f
-	arg := t.arg
-	seq := t.seq
-
-	if t.period > 0 {
-		// Leave in heap but adjust next time to fire.
-		delta := t.when - now
-		t.when += t.period * (1 + -delta/t.period)
-		if t.when < 0 { // check for overflow.
-			t.when = maxWhen
-		}
-		siftdownTimer(pp.timers, 0)
-		if !atomic.Cas(&t.status, timerRunning, timerWaiting) {
-			badTimer()
-		}
-		updateTimer0When(pp)
-	} else {
-		// Remove from heap.
-		dodeltimer0(pp)
-		if !atomic.Cas(&t.status, timerRunning, timerNoStatus) {
-			badTimer()
-		}
-	}
-
-	if raceenabled {
-		// Temporarily use the current P's racectx for g0.
-		gp := getg()
-		if gp.racectx != 0 {
-			throw("runOneTimer: unexpected racectx")
-		}
-		gp.racectx = gp.m.p.ptr().timerRaceCtx
-	}
-
-	unlock(&pp.timersLock)
-
-	f(arg, seq)
-
-	lock(&pp.timersLock)
-
-	if raceenabled {
-		gp := getg()
-		gp.racectx = 0
-	}
-}
-
-// clearDeletedTimers removes all deleted timers from the P's timer heap.
-// This is used to avoid clogging up the heap if the program
-// starts a lot of long-running timers and then stops them.
-// For example, this can happen via context.WithTimeout.
-//
-// This is the only function that walks through the entire timer heap,
-// other than moveTimers which only runs when the world is stopped.
-//
-// The caller must have locked the timers for pp.
-func clearDeletedTimers(pp *p) {
-	// We are going to clear all timerModifiedEarlier timers.
-	// Do this now in case new ones show up while we are looping.
-	atomic.Store64(&pp.timerModifiedEarliest, 0)
-
-	cdel := int32(0)
-	to := 0
-	changedHeap := false
-	timers := pp.timers
-nextTimer:
-	for _, t := range timers {
-		for {
-			switch s := atomic.Load(&t.status); s {
-			case timerWaiting:
-				if changedHeap {
-					timers[to] = t
-					siftupTimer(timers, to)
-				}
-				to++
-				continue nextTimer
-			case timerModifiedEarlier, timerModifiedLater:
-				if atomic.Cas(&t.status, s, timerMoving) {
-					t.when = t.nextwhen
-					timers[to] = t
-					siftupTimer(timers, to)
-					to++
-					changedHeap = true
-					if !atomic.Cas(&t.status, timerMoving, timerWaiting) {
-						badTimer()
-					}
-					continue nextTimer
-				}
-			case timerDeleted:
-				if atomic.Cas(&t.status, s, timerRemoving) {
-					t.pp = 0
-					cdel++
-					if !atomic.Cas(&t.status, timerRemoving, timerRemoved) {
-						badTimer()
-					}
-					changedHeap = true
-					continue nextTimer
-				}
-			case timerModifying:
-				// Loop until modification complete.
-				osyield()
-			case timerNoStatus, timerRemoved:
-				// We should not see these status values in a timer heap.
-				badTimer()
-			case timerRunning, timerRemoving, timerMoving:
-				// Some other P thinks it owns this timer,
-				// which should not happen.
-				badTimer()
-			default:
-				badTimer()
-			}
-		}
-	}
-
-	// Set remaining slots in timers slice to nil,
-	// so that the timer values can be garbage collected.
-	for i := to; i < len(timers); i++ {
-		timers[i] = nil
-	}
-
-	atomic.Xadd(&pp.deletedTimers, -cdel)
-	atomic.Xadd(&pp.numTimers, -cdel)
-
-	timers = timers[:to]
-	pp.timers = timers
-	updateTimer0When(pp)
-
-	if verifyTimers {
-		verifyTimerHeap(pp)
-	}
-}
-
-// verifyTimerHeap verifies that the timer heap is in a valid state.
-// This is only for debugging, and is only called if verifyTimers is true.
-// The caller must have locked the timers.
-func verifyTimerHeap(pp *p) {
-	for i, t := range pp.timers {
-		if i == 0 {
-			// First timer has no parent.
-			continue
-		}
-
-		// The heap is 4-ary. See siftupTimer and siftdownTimer.
-		p := (i - 1) / 4
-		if t.when < pp.timers[p].when {
-			print("bad timer heap at ", i, ": ", p, ": ", pp.timers[p].when, ", ", i, ": ", t.when, "\n")
-			throw("bad timer heap")
-		}
-	}
-	if numTimers := int(atomic.Load(&pp.numTimers)); len(pp.timers) != numTimers {
-		println("timer heap len", len(pp.timers), "!= numTimers", numTimers)
-		throw("bad timer heap len")
-	}
-}
-
-// updateTimer0When sets the P's timer0When field.
-// The caller must have locked the timers for pp.
-func updateTimer0When(pp *p) {
-	if len(pp.timers) == 0 {
-		atomic.Store64(&pp.timer0When, 0)
-	} else {
-		atomic.Store64(&pp.timer0When, uint64(pp.timers[0].when))
-	}
-}
-
-// updateTimerModifiedEarliest updates the recorded nextwhen field of the
-// earlier timerModifiedEarier value.
-// The timers for pp will not be locked.
-func updateTimerModifiedEarliest(pp *p, nextwhen int64) {
-	for {
-		old := atomic.Load64(&pp.timerModifiedEarliest)
-		if old != 0 && int64(old) < nextwhen {
-			return
-		}
-		if atomic.Cas64(&pp.timerModifiedEarliest, old, uint64(nextwhen)) {
-			return
-		}
-	}
-}
-
-// timeSleepUntil returns the time when the next timer should fire,
-// and the P that holds the timer heap that that timer is on.
-// This is only called by sysmon and checkdead.
-func timeSleepUntil() (int64, *p) {
-	next := int64(maxWhen)
-	var pret *p
-
-	// Prevent allp slice changes. This is like retake.
-	lock(&allpLock)
-	for _, pp := range allp {
-		if pp == nil {
-			// This can happen if procresize has grown
-			// allp but not yet created new Ps.
-			continue
-		}
-
-		w := int64(atomic.Load64(&pp.timer0When))
-		if w != 0 && w < next {
-			next = w
-			pret = pp
-		}
-
-		w = int64(atomic.Load64(&pp.timerModifiedEarliest))
-		if w != 0 && w < next {
-			next = w
-			pret = pp
-		}
-	}
-	unlock(&allpLock)
-
-	return next, pret
-}
-
-// Heap maintenance algorithms.
-// These algorithms check for slice index errors manually.
-// Slice index error can happen if the program is using racy
-// access to timers. We don't want to panic here, because
-// it will cause the program to crash with a mysterious
-// "panic holding locks" message. Instead, we panic while not
-// holding a lock.
-
-// siftupTimer puts the timer at position i in the right place
-// in the heap by moving it up toward the top of the heap.
-// It returns the smallest changed index.
-func siftupTimer(t []*timer, i int) int {
-	if i >= len(t) {
-		badTimer()
-	}
-	when := t[i].when
-	if when <= 0 {
-		badTimer()
-	}
-	tmp := t[i]
-	for i > 0 {
-		p := (i - 1) / 4 // parent
-		if when >= t[p].when {
-			break
-		}
-		t[i] = t[p]
-		i = p
-	}
-	if tmp != t[i] {
-		t[i] = tmp
-	}
-	return i
-}
-
-// siftdownTimer puts the timer at position i in the right place
-// in the heap by moving it down toward the bottom of the heap.
-func siftdownTimer(t []*timer, i int) {
-	n := len(t)
-	if i >= n {
-		badTimer()
-	}
-	when := t[i].when
-	if when <= 0 {
-		badTimer()
-	}
-	tmp := t[i]
-	for {
-		c := i*4 + 1 // left child
-		c3 := c + 2  // mid child
-		if c >= n {
-			break
-		}
-		w := t[c].when
-		if c+1 < n && t[c+1].when < w {
-			w = t[c+1].when
-			c++
-		}
-		if c3 < n {
-			w3 := t[c3].when
-			if c3+1 < n && t[c3+1].when < w3 {
-				w3 = t[c3+1].when
-				c3++
-			}
-			if w3 < w {
-				w = w3
-				c = c3
-			}
-		}
-		if w >= when {
-			break
-		}
-		t[i] = t[c]
-		i = c
-	}
-	if tmp != t[i] {
-		t[i] = tmp
-	}
-}
-
-// badTimer is called if the timer data structures have been corrupted,
-// presumably due to racy use by the program. We panic here rather than
-// panicing due to invalid slice access while holding locks.
-// See issue #25686.
-func badTimer() {
-	throw("timer data corruption")
-}
diff --git a/contrib/go/_std_1.18/src/runtime/trace.go b/contrib/go/_std_1.18/src/runtime/trace.go
deleted file mode 100644
index 8f60de2b05..0000000000
--- a/contrib/go/_std_1.18/src/runtime/trace.go
+++ /dev/null
@@ -1,1260 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Go execution tracer.
-// The tracer captures a wide range of execution events like goroutine
-// creation/blocking/unblocking, syscall enter/exit/block, GC-related events,
-// changes of heap size, processor start/stop, etc and writes them to a buffer
-// in a compact form. A precise nanosecond-precision timestamp and a stack
-// trace is captured for most events.
-// See https://golang.org/s/go15trace for more info.
-
-package runtime
-
-import (
-	"internal/goarch"
-	"runtime/internal/atomic"
-	"runtime/internal/sys"
-	"unsafe"
-)
-
-// Event types in the trace, args are given in square brackets.
-const (
-	traceEvNone              = 0  // unused
-	traceEvBatch             = 1  // start of per-P batch of events [pid, timestamp]
-	traceEvFrequency         = 2  // contains tracer timer frequency [frequency (ticks per second)]
-	traceEvStack             = 3  // stack [stack id, number of PCs, array of {PC, func string ID, file string ID, line}]
-	traceEvGomaxprocs        = 4  // current value of GOMAXPROCS [timestamp, GOMAXPROCS, stack id]
-	traceEvProcStart         = 5  // start of P [timestamp, thread id]
-	traceEvProcStop          = 6  // stop of P [timestamp]
-	traceEvGCStart           = 7  // GC start [timestamp, seq, stack id]
-	traceEvGCDone            = 8  // GC done [timestamp]
-	traceEvGCSTWStart        = 9  // GC STW start [timestamp, kind]
-	traceEvGCSTWDone         = 10 // GC STW done [timestamp]
-	traceEvGCSweepStart      = 11 // GC sweep start [timestamp, stack id]
-	traceEvGCSweepDone       = 12 // GC sweep done [timestamp, swept, reclaimed]
-	traceEvGoCreate          = 13 // goroutine creation [timestamp, new goroutine id, new stack id, stack id]
-	traceEvGoStart           = 14 // goroutine starts running [timestamp, goroutine id, seq]
-	traceEvGoEnd             = 15 // goroutine ends [timestamp]
-	traceEvGoStop            = 16 // goroutine stops (like in select{}) [timestamp, stack]
-	traceEvGoSched           = 17 // goroutine calls Gosched [timestamp, stack]
-	traceEvGoPreempt         = 18 // goroutine is preempted [timestamp, stack]
-	traceEvGoSleep           = 19 // goroutine calls Sleep [timestamp, stack]
-	traceEvGoBlock           = 20 // goroutine blocks [timestamp, stack]
-	traceEvGoUnblock         = 21 // goroutine is unblocked [timestamp, goroutine id, seq, stack]
-	traceEvGoBlockSend       = 22 // goroutine blocks on chan send [timestamp, stack]
-	traceEvGoBlockRecv       = 23 // goroutine blocks on chan recv [timestamp, stack]
-	traceEvGoBlockSelect     = 24 // goroutine blocks on select [timestamp, stack]
-	traceEvGoBlockSync       = 25 // goroutine blocks on Mutex/RWMutex [timestamp, stack]
-	traceEvGoBlockCond       = 26 // goroutine blocks on Cond [timestamp, stack]
-	traceEvGoBlockNet        = 27 // goroutine blocks on network [timestamp, stack]
-	traceEvGoSysCall         = 28 // syscall enter [timestamp, stack]
-	traceEvGoSysExit         = 29 // syscall exit [timestamp, goroutine id, seq, real timestamp]
-	traceEvGoSysBlock        = 30 // syscall blocks [timestamp]
-	traceEvGoWaiting         = 31 // denotes that goroutine is blocked when tracing starts [timestamp, goroutine id]
-	traceEvGoInSyscall       = 32 // denotes that goroutine is in syscall when tracing starts [timestamp, goroutine id]
-	traceEvHeapAlloc         = 33 // gcController.heapLive change [timestamp, heap_alloc]
-	traceEvHeapGoal          = 34 // gcController.heapGoal (formerly next_gc) change [timestamp, heap goal in bytes]
-	traceEvTimerGoroutine    = 35 // not currently used; previously denoted timer goroutine [timer goroutine id]
-	traceEvFutileWakeup      = 36 // denotes that the previous wakeup of this goroutine was futile [timestamp]
-	traceEvString            = 37 // string dictionary entry [ID, length, string]
-	traceEvGoStartLocal      = 38 // goroutine starts running on the same P as the last event [timestamp, goroutine id]
-	traceEvGoUnblockLocal    = 39 // goroutine is unblocked on the same P as the last event [timestamp, goroutine id, stack]
-	traceEvGoSysExitLocal    = 40 // syscall exit on the same P as the last event [timestamp, goroutine id, real timestamp]
-	traceEvGoStartLabel      = 41 // goroutine starts running with label [timestamp, goroutine id, seq, label string id]
-	traceEvGoBlockGC         = 42 // goroutine blocks on GC assist [timestamp, stack]
-	traceEvGCMarkAssistStart = 43 // GC mark assist start [timestamp, stack]
-	traceEvGCMarkAssistDone  = 44 // GC mark assist done [timestamp]
-	traceEvUserTaskCreate    = 45 // trace.NewContext [timestamp, internal task id, internal parent task id, stack, name string]
-	traceEvUserTaskEnd       = 46 // end of a task [timestamp, internal task id, stack]
-	traceEvUserRegion        = 47 // trace.WithRegion [timestamp, internal task id, mode(0:start, 1:end), stack, name string]
-	traceEvUserLog           = 48 // trace.Log [timestamp, internal task id, key string id, stack, value string]
-	traceEvCount             = 49
-	// Byte is used but only 6 bits are available for event type.
-	// The remaining 2 bits are used to specify the number of arguments.
-	// That means, the max event type value is 63.
-)
-
-const (
-	// Timestamps in trace are cputicks/traceTickDiv.
-	// This makes absolute values of timestamp diffs smaller,
-	// and so they are encoded in less number of bytes.
-	// 64 on x86 is somewhat arbitrary (one tick is ~20ns on a 3GHz machine).
-	// The suggested increment frequency for PowerPC's time base register is
-	// 512 MHz according to Power ISA v2.07 section 6.2, so we use 16 on ppc64
-	// and ppc64le.
-	// Tracing won't work reliably for architectures where cputicks is emulated
-	// by nanotime, so the value doesn't matter for those architectures.
-	traceTickDiv = 16 + 48*(goarch.Is386|goarch.IsAmd64)
-	// Maximum number of PCs in a single stack trace.
-	// Since events contain only stack id rather than whole stack trace,
-	// we can allow quite large values here.
-	traceStackSize = 128
-	// Identifier of a fake P that is used when we trace without a real P.
-	traceGlobProc = -1
-	// Maximum number of bytes to encode uint64 in base-128.
-	traceBytesPerNumber = 10
-	// Shift of the number of arguments in the first event byte.
-	traceArgCountShift = 6
-	// Flag passed to traceGoPark to denote that the previous wakeup of this
-	// goroutine was futile. For example, a goroutine was unblocked on a mutex,
-	// but another goroutine got ahead and acquired the mutex before the first
-	// goroutine is scheduled, so the first goroutine has to block again.
-	// Such wakeups happen on buffered channels and sync.Mutex,
-	// but are generally not interesting for end user.
-	traceFutileWakeup byte = 128
-)
-
-// trace is global tracing context.
-var trace struct {
-	lock          mutex       // protects the following members
-	lockOwner     *g          // to avoid deadlocks during recursive lock locks
-	enabled       bool        // when set runtime traces events
-	shutdown      bool        // set when we are waiting for trace reader to finish after setting enabled to false
-	headerWritten bool        // whether ReadTrace has emitted trace header
-	footerWritten bool        // whether ReadTrace has emitted trace footer
-	shutdownSema  uint32      // used to wait for ReadTrace completion
-	seqStart      uint64      // sequence number when tracing was started
-	ticksStart    int64       // cputicks when tracing was started
-	ticksEnd      int64       // cputicks when tracing was stopped
-	timeStart     int64       // nanotime when tracing was started
-	timeEnd       int64       // nanotime when tracing was stopped
-	seqGC         uint64      // GC start/done sequencer
-	reading       traceBufPtr // buffer currently handed off to user
-	empty         traceBufPtr // stack of empty buffers
-	fullHead      traceBufPtr // queue of full buffers
-	fullTail      traceBufPtr
-	reader        guintptr        // goroutine that called ReadTrace, or nil
-	stackTab      traceStackTable // maps stack traces to unique ids
-
-	// Dictionary for traceEvString.
-	//
-	// TODO: central lock to access the map is not ideal.
-	//   option: pre-assign ids to all user annotation region names and tags
-	//   option: per-P cache
-	//   option: sync.Map like data structure
-	stringsLock mutex
-	strings     map[string]uint64
-	stringSeq   uint64
-
-	// markWorkerLabels maps gcMarkWorkerMode to string ID.
-	markWorkerLabels [len(gcMarkWorkerModeStrings)]uint64
-
-	bufLock mutex       // protects buf
-	buf     traceBufPtr // global trace buffer, used when running without a p
-}
-
-// traceBufHeader is per-P tracing buffer.
-type traceBufHeader struct {
-	link      traceBufPtr             // in trace.empty/full
-	lastTicks uint64                  // when we wrote the last event
-	pos       int                     // next write offset in arr
-	stk       [traceStackSize]uintptr // scratch buffer for traceback
-}
-
-// traceBuf is per-P tracing buffer.
-//
-//go:notinheap
-type traceBuf struct {
-	traceBufHeader
-	arr [64<<10 - unsafe.Sizeof(traceBufHeader{})]byte // underlying buffer for traceBufHeader.buf
-}
-
-// traceBufPtr is a *traceBuf that is not traced by the garbage
-// collector and doesn't have write barriers. traceBufs are not
-// allocated from the GC'd heap, so this is safe, and are often
-// manipulated in contexts where write barriers are not allowed, so
-// this is necessary.
-//
-// TODO: Since traceBuf is now go:notinheap, this isn't necessary.
-type traceBufPtr uintptr
-
-func (tp traceBufPtr) ptr() *traceBuf   { return (*traceBuf)(unsafe.Pointer(tp)) }
-func (tp *traceBufPtr) set(b *traceBuf) { *tp = traceBufPtr(unsafe.Pointer(b)) }
-func traceBufPtrOf(b *traceBuf) traceBufPtr {
-	return traceBufPtr(unsafe.Pointer(b))
-}
-
-// StartTrace enables tracing for the current process.
-// While tracing, the data will be buffered and available via ReadTrace.
-// StartTrace returns an error if tracing is already enabled.
-// Most clients should use the runtime/trace package or the testing package's
-// -test.trace flag instead of calling StartTrace directly.
-func StartTrace() error {
-	// Stop the world so that we can take a consistent snapshot
-	// of all goroutines at the beginning of the trace.
-	// Do not stop the world during GC so we ensure we always see
-	// a consistent view of GC-related events (e.g. a start is always
-	// paired with an end).
-	stopTheWorldGC("start tracing")
-
-	// Prevent sysmon from running any code that could generate events.
-	lock(&sched.sysmonlock)
-
-	// We are in stop-the-world, but syscalls can finish and write to trace concurrently.
-	// Exitsyscall could check trace.enabled long before and then suddenly wake up
-	// and decide to write to trace at a random point in time.
-	// However, such syscall will use the global trace.buf buffer, because we've
-	// acquired all p's by doing stop-the-world. So this protects us from such races.
-	lock(&trace.bufLock)
-
-	if trace.enabled || trace.shutdown {
-		unlock(&trace.bufLock)
-		unlock(&sched.sysmonlock)
-		startTheWorldGC()
-		return errorString("tracing is already enabled")
-	}
-
-	// Can't set trace.enabled yet. While the world is stopped, exitsyscall could
-	// already emit a delayed event (see exitTicks in exitsyscall) if we set trace.enabled here.
-	// That would lead to an inconsistent trace:
-	// - either GoSysExit appears before EvGoInSyscall,
-	// - or GoSysExit appears for a goroutine for which we don't emit EvGoInSyscall below.
-	// To instruct traceEvent that it must not ignore events below, we set startingtrace.
-	// trace.enabled is set afterwards once we have emitted all preliminary events.
-	_g_ := getg()
-	_g_.m.startingtrace = true
-
-	// Obtain current stack ID to use in all traceEvGoCreate events below.
-	mp := acquirem()
-	stkBuf := make([]uintptr, traceStackSize)
-	stackID := traceStackID(mp, stkBuf, 2)
-	releasem(mp)
-
-	// World is stopped, no need to lock.
-	forEachGRace(func(gp *g) {
-		status := readgstatus(gp)
-		if status != _Gdead {
-			gp.traceseq = 0
-			gp.tracelastp = getg().m.p
-			// +PCQuantum because traceFrameForPC expects return PCs and subtracts PCQuantum.
-			id := trace.stackTab.put([]uintptr{startPCforTrace(gp.startpc) + sys.PCQuantum})
-			traceEvent(traceEvGoCreate, -1, uint64(gp.goid), uint64(id), stackID)
-		}
-		if status == _Gwaiting {
-			// traceEvGoWaiting is implied to have seq=1.
-			gp.traceseq++
-			traceEvent(traceEvGoWaiting, -1, uint64(gp.goid))
-		}
-		if status == _Gsyscall {
-			gp.traceseq++
-			traceEvent(traceEvGoInSyscall, -1, uint64(gp.goid))
-		} else {
-			gp.sysblocktraced = false
-		}
-	})
-	traceProcStart()
-	traceGoStart()
-	// Note: ticksStart needs to be set after we emit traceEvGoInSyscall events.
-	// If we do it the other way around, it is possible that exitsyscall will
-	// query sysexitticks after ticksStart but before traceEvGoInSyscall timestamp.
-	// It will lead to a false conclusion that cputicks is broken.
-	trace.ticksStart = cputicks()
-	trace.timeStart = nanotime()
-	trace.headerWritten = false
-	trace.footerWritten = false
-
-	// string to id mapping
-	//  0 : reserved for an empty string
-	//  remaining: other strings registered by traceString
-	trace.stringSeq = 0
-	trace.strings = make(map[string]uint64)
-
-	trace.seqGC = 0
-	_g_.m.startingtrace = false
-	trace.enabled = true
-
-	// Register runtime goroutine labels.
-	_, pid, bufp := traceAcquireBuffer()
-	for i, label := range gcMarkWorkerModeStrings[:] {
-		trace.markWorkerLabels[i], bufp = traceString(bufp, pid, label)
-	}
-	traceReleaseBuffer(pid)
-
-	unlock(&trace.bufLock)
-
-	unlock(&sched.sysmonlock)
-
-	startTheWorldGC()
-	return nil
-}
-
-// StopTrace stops tracing, if it was previously enabled.
-// StopTrace only returns after all the reads for the trace have completed.
-func StopTrace() {
-	// Stop the world so that we can collect the trace buffers from all p's below,
-	// and also to avoid races with traceEvent.
-	stopTheWorldGC("stop tracing")
-
-	// See the comment in StartTrace.
-	lock(&sched.sysmonlock)
-
-	// See the comment in StartTrace.
-	lock(&trace.bufLock)
-
-	if !trace.enabled {
-		unlock(&trace.bufLock)
-		unlock(&sched.sysmonlock)
-		startTheWorldGC()
-		return
-	}
-
-	traceGoSched()
-
-	// Loop over all allocated Ps because dead Ps may still have
-	// trace buffers.
-	for _, p := range allp[:cap(allp)] {
-		buf := p.tracebuf
-		if buf != 0 {
-			traceFullQueue(buf)
-			p.tracebuf = 0
-		}
-	}
-	if trace.buf != 0 {
-		buf := trace.buf
-		trace.buf = 0
-		if buf.ptr().pos != 0 {
-			traceFullQueue(buf)
-		}
-	}
-
-	for {
-		trace.ticksEnd = cputicks()
-		trace.timeEnd = nanotime()
-		// Windows time can tick only every 15ms, wait for at least one tick.
-		if trace.timeEnd != trace.timeStart {
-			break
-		}
-		osyield()
-	}
-
-	trace.enabled = false
-	trace.shutdown = true
-	unlock(&trace.bufLock)
-
-	unlock(&sched.sysmonlock)
-
-	startTheWorldGC()
-
-	// The world is started but we've set trace.shutdown, so new tracing can't start.
-	// Wait for the trace reader to flush pending buffers and stop.
-	semacquire(&trace.shutdownSema)
-	if raceenabled {
-		raceacquire(unsafe.Pointer(&trace.shutdownSema))
-	}
-
-	// The lock protects us from races with StartTrace/StopTrace because they do stop-the-world.
-	lock(&trace.lock)
-	for _, p := range allp[:cap(allp)] {
-		if p.tracebuf != 0 {
-			throw("trace: non-empty trace buffer in proc")
-		}
-	}
-	if trace.buf != 0 {
-		throw("trace: non-empty global trace buffer")
-	}
-	if trace.fullHead != 0 || trace.fullTail != 0 {
-		throw("trace: non-empty full trace buffer")
-	}
-	if trace.reading != 0 || trace.reader != 0 {
-		throw("trace: reading after shutdown")
-	}
-	for trace.empty != 0 {
-		buf := trace.empty
-		trace.empty = buf.ptr().link
-		sysFree(unsafe.Pointer(buf), unsafe.Sizeof(*buf.ptr()), &memstats.other_sys)
-	}
-	trace.strings = nil
-	trace.shutdown = false
-	unlock(&trace.lock)
-}
-
-// ReadTrace returns the next chunk of binary tracing data, blocking until data
-// is available. If tracing is turned off and all the data accumulated while it
-// was on has been returned, ReadTrace returns nil. The caller must copy the
-// returned data before calling ReadTrace again.
-// ReadTrace must be called from one goroutine at a time.
-func ReadTrace() []byte {
-	// This function may need to lock trace.lock recursively
-	// (goparkunlock -> traceGoPark -> traceEvent -> traceFlush).
-	// To allow this we use trace.lockOwner.
-	// Also this function must not allocate while holding trace.lock:
-	// allocation can call heap allocate, which will try to emit a trace
-	// event while holding heap lock.
-	lock(&trace.lock)
-	trace.lockOwner = getg()
-
-	if trace.reader != 0 {
-		// More than one goroutine reads trace. This is bad.
-		// But we rather do not crash the program because of tracing,
-		// because tracing can be enabled at runtime on prod servers.
-		trace.lockOwner = nil
-		unlock(&trace.lock)
-		println("runtime: ReadTrace called from multiple goroutines simultaneously")
-		return nil
-	}
-	// Recycle the old buffer.
-	if buf := trace.reading; buf != 0 {
-		buf.ptr().link = trace.empty
-		trace.empty = buf
-		trace.reading = 0
-	}
-	// Write trace header.
-	if !trace.headerWritten {
-		trace.headerWritten = true
-		trace.lockOwner = nil
-		unlock(&trace.lock)
-		return []byte("go 1.11 trace\x00\x00\x00")
-	}
-	// Wait for new data.
-	if trace.fullHead == 0 && !trace.shutdown {
-		trace.reader.set(getg())
-		goparkunlock(&trace.lock, waitReasonTraceReaderBlocked, traceEvGoBlock, 2)
-		lock(&trace.lock)
-	}
-	// Write a buffer.
-	if trace.fullHead != 0 {
-		buf := traceFullDequeue()
-		trace.reading = buf
-		trace.lockOwner = nil
-		unlock(&trace.lock)
-		return buf.ptr().arr[:buf.ptr().pos]
-	}
-	// Write footer with timer frequency.
-	if !trace.footerWritten {
-		trace.footerWritten = true
-		// Use float64 because (trace.ticksEnd - trace.ticksStart) * 1e9 can overflow int64.
-		freq := float64(trace.ticksEnd-trace.ticksStart) * 1e9 / float64(trace.timeEnd-trace.timeStart) / traceTickDiv
-		if freq <= 0 {
-			throw("trace: ReadTrace got invalid frequency")
-		}
-		trace.lockOwner = nil
-		unlock(&trace.lock)
-		var data []byte
-		data = append(data, traceEvFrequency|0<<traceArgCountShift)
-		data = traceAppend(data, uint64(freq))
-		// This will emit a bunch of full buffers, we will pick them up
-		// on the next iteration.
-		trace.stackTab.dump()
-		return data
-	}
-	// Done.
-	if trace.shutdown {
-		trace.lockOwner = nil
-		unlock(&trace.lock)
-		if raceenabled {
-			// Model synchronization on trace.shutdownSema, which race
-			// detector does not see. This is required to avoid false
-			// race reports on writer passed to trace.Start.
-			racerelease(unsafe.Pointer(&trace.shutdownSema))
-		}
-		// trace.enabled is already reset, so can call traceable functions.
-		semrelease(&trace.shutdownSema)
-		return nil
-	}
-	// Also bad, but see the comment above.
-	trace.lockOwner = nil
-	unlock(&trace.lock)
-	println("runtime: spurious wakeup of trace reader")
-	return nil
-}
-
-// traceReader returns the trace reader that should be woken up, if any.
-func traceReader() *g {
-	if trace.reader == 0 || (trace.fullHead == 0 && !trace.shutdown) {
-		return nil
-	}
-	lock(&trace.lock)
-	if trace.reader == 0 || (trace.fullHead == 0 && !trace.shutdown) {
-		unlock(&trace.lock)
-		return nil
-	}
-	gp := trace.reader.ptr()
-	trace.reader.set(nil)
-	unlock(&trace.lock)
-	return gp
-}
-
-// traceProcFree frees trace buffer associated with pp.
-func traceProcFree(pp *p) {
-	buf := pp.tracebuf
-	pp.tracebuf = 0
-	if buf == 0 {
-		return
-	}
-	lock(&trace.lock)
-	traceFullQueue(buf)
-	unlock(&trace.lock)
-}
-
-// traceFullQueue queues buf into queue of full buffers.
-func traceFullQueue(buf traceBufPtr) {
-	buf.ptr().link = 0
-	if trace.fullHead == 0 {
-		trace.fullHead = buf
-	} else {
-		trace.fullTail.ptr().link = buf
-	}
-	trace.fullTail = buf
-}
-
-// traceFullDequeue dequeues from queue of full buffers.
-func traceFullDequeue() traceBufPtr {
-	buf := trace.fullHead
-	if buf == 0 {
-		return 0
-	}
-	trace.fullHead = buf.ptr().link
-	if trace.fullHead == 0 {
-		trace.fullTail = 0
-	}
-	buf.ptr().link = 0
-	return buf
-}
-
-// traceEvent writes a single event to trace buffer, flushing the buffer if necessary.
-// ev is event type.
-// If skip > 0, write current stack id as the last argument (skipping skip top frames).
-// If skip = 0, this event type should contain a stack, but we don't want
-// to collect and remember it for this particular call.
-func traceEvent(ev byte, skip int, args ...uint64) {
-	mp, pid, bufp := traceAcquireBuffer()
-	// Double-check trace.enabled now that we've done m.locks++ and acquired bufLock.
-	// This protects from races between traceEvent and StartTrace/StopTrace.
-
-	// The caller checked that trace.enabled == true, but trace.enabled might have been
-	// turned off between the check and now. Check again. traceLockBuffer did mp.locks++,
-	// StopTrace does stopTheWorld, and stopTheWorld waits for mp.locks to go back to zero,
-	// so if we see trace.enabled == true now, we know it's true for the rest of the function.
-	// Exitsyscall can run even during stopTheWorld. The race with StartTrace/StopTrace
-	// during tracing in exitsyscall is resolved by locking trace.bufLock in traceLockBuffer.
-	//
-	// Note trace_userTaskCreate runs the same check.
-	if !trace.enabled && !mp.startingtrace {
-		traceReleaseBuffer(pid)
-		return
-	}
-
-	if skip > 0 {
-		if getg() == mp.curg {
-			skip++ // +1 because stack is captured in traceEventLocked.
-		}
-	}
-	traceEventLocked(0, mp, pid, bufp, ev, skip, args...)
-	traceReleaseBuffer(pid)
-}
-
-func traceEventLocked(extraBytes int, mp *m, pid int32, bufp *traceBufPtr, ev byte, skip int, args ...uint64) {
-	buf := bufp.ptr()
-	// TODO: test on non-zero extraBytes param.
-	maxSize := 2 + 5*traceBytesPerNumber + extraBytes // event type, length, sequence, timestamp, stack id and two add params
-	if buf == nil || len(buf.arr)-buf.pos < maxSize {
-		buf = traceFlush(traceBufPtrOf(buf), pid).ptr()
-		bufp.set(buf)
-	}
-
-	// NOTE: ticks might be same after tick division, although the real cputicks is
-	// linear growth.
-	ticks := uint64(cputicks()) / traceTickDiv
-	tickDiff := ticks - buf.lastTicks
-	if tickDiff == 0 {
-		ticks = buf.lastTicks + 1
-		tickDiff = 1
-	}
-
-	buf.lastTicks = ticks
-	narg := byte(len(args))
-	if skip >= 0 {
-		narg++
-	}
-	// We have only 2 bits for number of arguments.
-	// If number is >= 3, then the event type is followed by event length in bytes.
-	if narg > 3 {
-		narg = 3
-	}
-	startPos := buf.pos
-	buf.byte(ev | narg<<traceArgCountShift)
-	var lenp *byte
-	if narg == 3 {
-		// Reserve the byte for length assuming that length < 128.
-		buf.varint(0)
-		lenp = &buf.arr[buf.pos-1]
-	}
-	buf.varint(tickDiff)
-	for _, a := range args {
-		buf.varint(a)
-	}
-	if skip == 0 {
-		buf.varint(0)
-	} else if skip > 0 {
-		buf.varint(traceStackID(mp, buf.stk[:], skip))
-	}
-	evSize := buf.pos - startPos
-	if evSize > maxSize {
-		throw("invalid length of trace event")
-	}
-	if lenp != nil {
-		// Fill in actual length.
-		*lenp = byte(evSize - 2)
-	}
-}
-
-func traceStackID(mp *m, buf []uintptr, skip int) uint64 {
-	_g_ := getg()
-	gp := mp.curg
-	var nstk int
-	if gp == _g_ {
-		nstk = callers(skip+1, buf)
-	} else if gp != nil {
-		gp = mp.curg
-		nstk = gcallers(gp, skip, buf)
-	}
-	if nstk > 0 {
-		nstk-- // skip runtime.goexit
-	}
-	if nstk > 0 && gp.goid == 1 {
-		nstk-- // skip runtime.main
-	}
-	id := trace.stackTab.put(buf[:nstk])
-	return uint64(id)
-}
-
-// traceAcquireBuffer returns trace buffer to use and, if necessary, locks it.
-func traceAcquireBuffer() (mp *m, pid int32, bufp *traceBufPtr) {
-	mp = acquirem()
-	if p := mp.p.ptr(); p != nil {
-		return mp, p.id, &p.tracebuf
-	}
-	lock(&trace.bufLock)
-	return mp, traceGlobProc, &trace.buf
-}
-
-// traceReleaseBuffer releases a buffer previously acquired with traceAcquireBuffer.
-func traceReleaseBuffer(pid int32) {
-	if pid == traceGlobProc {
-		unlock(&trace.bufLock)
-	}
-	releasem(getg().m)
-}
-
-// traceFlush puts buf onto stack of full buffers and returns an empty buffer.
-func traceFlush(buf traceBufPtr, pid int32) traceBufPtr {
-	owner := trace.lockOwner
-	dolock := owner == nil || owner != getg().m.curg
-	if dolock {
-		lock(&trace.lock)
-	}
-	if buf != 0 {
-		traceFullQueue(buf)
-	}
-	if trace.empty != 0 {
-		buf = trace.empty
-		trace.empty = buf.ptr().link
-	} else {
-		buf = traceBufPtr(sysAlloc(unsafe.Sizeof(traceBuf{}), &memstats.other_sys))
-		if buf == 0 {
-			throw("trace: out of memory")
-		}
-	}
-	bufp := buf.ptr()
-	bufp.link.set(nil)
-	bufp.pos = 0
-
-	// initialize the buffer for a new batch
-	ticks := uint64(cputicks()) / traceTickDiv
-	if ticks == bufp.lastTicks {
-		ticks = bufp.lastTicks + 1
-	}
-	bufp.lastTicks = ticks
-	bufp.byte(traceEvBatch | 1<<traceArgCountShift)
-	bufp.varint(uint64(pid))
-	bufp.varint(ticks)
-
-	if dolock {
-		unlock(&trace.lock)
-	}
-	return buf
-}
-
-// traceString adds a string to the trace.strings and returns the id.
-func traceString(bufp *traceBufPtr, pid int32, s string) (uint64, *traceBufPtr) {
-	if s == "" {
-		return 0, bufp
-	}
-
-	lock(&trace.stringsLock)
-	if raceenabled {
-		// raceacquire is necessary because the map access
-		// below is race annotated.
-		raceacquire(unsafe.Pointer(&trace.stringsLock))
-	}
-
-	if id, ok := trace.strings[s]; ok {
-		if raceenabled {
-			racerelease(unsafe.Pointer(&trace.stringsLock))
-		}
-		unlock(&trace.stringsLock)
-
-		return id, bufp
-	}
-
-	trace.stringSeq++
-	id := trace.stringSeq
-	trace.strings[s] = id
-
-	if raceenabled {
-		racerelease(unsafe.Pointer(&trace.stringsLock))
-	}
-	unlock(&trace.stringsLock)
-
-	// memory allocation in above may trigger tracing and
-	// cause *bufp changes. Following code now works with *bufp,
-	// so there must be no memory allocation or any activities
-	// that causes tracing after this point.
-
-	buf := bufp.ptr()
-	size := 1 + 2*traceBytesPerNumber + len(s)
-	if buf == nil || len(buf.arr)-buf.pos < size {
-		buf = traceFlush(traceBufPtrOf(buf), pid).ptr()
-		bufp.set(buf)
-	}
-	buf.byte(traceEvString)
-	buf.varint(id)
-
-	// double-check the string and the length can fit.
-	// Otherwise, truncate the string.
-	slen := len(s)
-	if room := len(buf.arr) - buf.pos; room < slen+traceBytesPerNumber {
-		slen = room
-	}
-
-	buf.varint(uint64(slen))
-	buf.pos += copy(buf.arr[buf.pos:], s[:slen])
-
-	bufp.set(buf)
-	return id, bufp
-}
-
-// traceAppend appends v to buf in little-endian-base-128 encoding.
-func traceAppend(buf []byte, v uint64) []byte {
-	for ; v >= 0x80; v >>= 7 {
-		buf = append(buf, 0x80|byte(v))
-	}
-	buf = append(buf, byte(v))
-	return buf
-}
-
-// varint appends v to buf in little-endian-base-128 encoding.
-func (buf *traceBuf) varint(v uint64) {
-	pos := buf.pos
-	for ; v >= 0x80; v >>= 7 {
-		buf.arr[pos] = 0x80 | byte(v)
-		pos++
-	}
-	buf.arr[pos] = byte(v)
-	pos++
-	buf.pos = pos
-}
-
-// byte appends v to buf.
-func (buf *traceBuf) byte(v byte) {
-	buf.arr[buf.pos] = v
-	buf.pos++
-}
-
-// traceStackTable maps stack traces (arrays of PC's) to unique uint32 ids.
-// It is lock-free for reading.
-type traceStackTable struct {
-	lock mutex
-	seq  uint32
-	mem  traceAlloc
-	tab  [1 << 13]traceStackPtr
-}
-
-// traceStack is a single stack in traceStackTable.
-type traceStack struct {
-	link traceStackPtr
-	hash uintptr
-	id   uint32
-	n    int
-	stk  [0]uintptr // real type [n]uintptr
-}
-
-type traceStackPtr uintptr
-
-func (tp traceStackPtr) ptr() *traceStack { return (*traceStack)(unsafe.Pointer(tp)) }
-
-// stack returns slice of PCs.
-func (ts *traceStack) stack() []uintptr {
-	return (*[traceStackSize]uintptr)(unsafe.Pointer(&ts.stk))[:ts.n]
-}
-
-// put returns a unique id for the stack trace pcs and caches it in the table,
-// if it sees the trace for the first time.
-func (tab *traceStackTable) put(pcs []uintptr) uint32 {
-	if len(pcs) == 0 {
-		return 0
-	}
-	hash := memhash(unsafe.Pointer(&pcs[0]), 0, uintptr(len(pcs))*unsafe.Sizeof(pcs[0]))
-	// First, search the hashtable w/o the mutex.
-	if id := tab.find(pcs, hash); id != 0 {
-		return id
-	}
-	// Now, double check under the mutex.
-	lock(&tab.lock)
-	if id := tab.find(pcs, hash); id != 0 {
-		unlock(&tab.lock)
-		return id
-	}
-	// Create new record.
-	tab.seq++
-	stk := tab.newStack(len(pcs))
-	stk.hash = hash
-	stk.id = tab.seq
-	stk.n = len(pcs)
-	stkpc := stk.stack()
-	for i, pc := range pcs {
-		stkpc[i] = pc
-	}
-	part := int(hash % uintptr(len(tab.tab)))
-	stk.link = tab.tab[part]
-	atomicstorep(unsafe.Pointer(&tab.tab[part]), unsafe.Pointer(stk))
-	unlock(&tab.lock)
-	return stk.id
-}
-
-// find checks if the stack trace pcs is already present in the table.
-func (tab *traceStackTable) find(pcs []uintptr, hash uintptr) uint32 {
-	part := int(hash % uintptr(len(tab.tab)))
-Search:
-	for stk := tab.tab[part].ptr(); stk != nil; stk = stk.link.ptr() {
-		if stk.hash == hash && stk.n == len(pcs) {
-			for i, stkpc := range stk.stack() {
-				if stkpc != pcs[i] {
-					continue Search
-				}
-			}
-			return stk.id
-		}
-	}
-	return 0
-}
-
-// newStack allocates a new stack of size n.
-func (tab *traceStackTable) newStack(n int) *traceStack {
-	return (*traceStack)(tab.mem.alloc(unsafe.Sizeof(traceStack{}) + uintptr(n)*goarch.PtrSize))
-}
-
-// allFrames returns all of the Frames corresponding to pcs.
-func allFrames(pcs []uintptr) []Frame {
-	frames := make([]Frame, 0, len(pcs))
-	ci := CallersFrames(pcs)
-	for {
-		f, more := ci.Next()
-		frames = append(frames, f)
-		if !more {
-			return frames
-		}
-	}
-}
-
-// dump writes all previously cached stacks to trace buffers,
-// releases all memory and resets state.
-func (tab *traceStackTable) dump() {
-	var tmp [(2 + 4*traceStackSize) * traceBytesPerNumber]byte
-	bufp := traceFlush(0, 0)
-	for _, stk := range tab.tab {
-		stk := stk.ptr()
-		for ; stk != nil; stk = stk.link.ptr() {
-			tmpbuf := tmp[:0]
-			tmpbuf = traceAppend(tmpbuf, uint64(stk.id))
-			frames := allFrames(stk.stack())
-			tmpbuf = traceAppend(tmpbuf, uint64(len(frames)))
-			for _, f := range frames {
-				var frame traceFrame
-				frame, bufp = traceFrameForPC(bufp, 0, f)
-				tmpbuf = traceAppend(tmpbuf, uint64(f.PC))
-				tmpbuf = traceAppend(tmpbuf, uint64(frame.funcID))
-				tmpbuf = traceAppend(tmpbuf, uint64(frame.fileID))
-				tmpbuf = traceAppend(tmpbuf, uint64(frame.line))
-			}
-			// Now copy to the buffer.
-			size := 1 + traceBytesPerNumber + len(tmpbuf)
-			if buf := bufp.ptr(); len(buf.arr)-buf.pos < size {
-				bufp = traceFlush(bufp, 0)
-			}
-			buf := bufp.ptr()
-			buf.byte(traceEvStack | 3<<traceArgCountShift)
-			buf.varint(uint64(len(tmpbuf)))
-			buf.pos += copy(buf.arr[buf.pos:], tmpbuf)
-		}
-	}
-
-	lock(&trace.lock)
-	traceFullQueue(bufp)
-	unlock(&trace.lock)
-
-	tab.mem.drop()
-	*tab = traceStackTable{}
-	lockInit(&((*tab).lock), lockRankTraceStackTab)
-}
-
-type traceFrame struct {
-	funcID uint64
-	fileID uint64
-	line   uint64
-}
-
-// traceFrameForPC records the frame information.
-// It may allocate memory.
-func traceFrameForPC(buf traceBufPtr, pid int32, f Frame) (traceFrame, traceBufPtr) {
-	bufp := &buf
-	var frame traceFrame
-
-	fn := f.Function
-	const maxLen = 1 << 10
-	if len(fn) > maxLen {
-		fn = fn[len(fn)-maxLen:]
-	}
-	frame.funcID, bufp = traceString(bufp, pid, fn)
-	frame.line = uint64(f.Line)
-	file := f.File
-	if len(file) > maxLen {
-		file = file[len(file)-maxLen:]
-	}
-	frame.fileID, bufp = traceString(bufp, pid, file)
-	return frame, (*bufp)
-}
-
-// traceAlloc is a non-thread-safe region allocator.
-// It holds a linked list of traceAllocBlock.
-type traceAlloc struct {
-	head traceAllocBlockPtr
-	off  uintptr
-}
-
-// traceAllocBlock is a block in traceAlloc.
-//
-// traceAllocBlock is allocated from non-GC'd memory, so it must not
-// contain heap pointers. Writes to pointers to traceAllocBlocks do
-// not need write barriers.
-//
-//go:notinheap
-type traceAllocBlock struct {
-	next traceAllocBlockPtr
-	data [64<<10 - goarch.PtrSize]byte
-}
-
-// TODO: Since traceAllocBlock is now go:notinheap, this isn't necessary.
-type traceAllocBlockPtr uintptr
-
-func (p traceAllocBlockPtr) ptr() *traceAllocBlock   { return (*traceAllocBlock)(unsafe.Pointer(p)) }
-func (p *traceAllocBlockPtr) set(x *traceAllocBlock) { *p = traceAllocBlockPtr(unsafe.Pointer(x)) }
-
-// alloc allocates n-byte block.
-func (a *traceAlloc) alloc(n uintptr) unsafe.Pointer {
-	n = alignUp(n, goarch.PtrSize)
-	if a.head == 0 || a.off+n > uintptr(len(a.head.ptr().data)) {
-		if n > uintptr(len(a.head.ptr().data)) {
-			throw("trace: alloc too large")
-		}
-		block := (*traceAllocBlock)(sysAlloc(unsafe.Sizeof(traceAllocBlock{}), &memstats.other_sys))
-		if block == nil {
-			throw("trace: out of memory")
-		}
-		block.next.set(a.head.ptr())
-		a.head.set(block)
-		a.off = 0
-	}
-	p := &a.head.ptr().data[a.off]
-	a.off += n
-	return unsafe.Pointer(p)
-}
-
-// drop frees all previously allocated memory and resets the allocator.
-func (a *traceAlloc) drop() {
-	for a.head != 0 {
-		block := a.head.ptr()
-		a.head.set(block.next.ptr())
-		sysFree(unsafe.Pointer(block), unsafe.Sizeof(traceAllocBlock{}), &memstats.other_sys)
-	}
-}
-
-// The following functions write specific events to trace.
-
-func traceGomaxprocs(procs int32) {
-	traceEvent(traceEvGomaxprocs, 1, uint64(procs))
-}
-
-func traceProcStart() {
-	traceEvent(traceEvProcStart, -1, uint64(getg().m.id))
-}
-
-func traceProcStop(pp *p) {
-	// Sysmon and stopTheWorld can stop Ps blocked in syscalls,
-	// to handle this we temporary employ the P.
-	mp := acquirem()
-	oldp := mp.p
-	mp.p.set(pp)
-	traceEvent(traceEvProcStop, -1)
-	mp.p = oldp
-	releasem(mp)
-}
-
-func traceGCStart() {
-	traceEvent(traceEvGCStart, 3, trace.seqGC)
-	trace.seqGC++
-}
-
-func traceGCDone() {
-	traceEvent(traceEvGCDone, -1)
-}
-
-func traceGCSTWStart(kind int) {
-	traceEvent(traceEvGCSTWStart, -1, uint64(kind))
-}
-
-func traceGCSTWDone() {
-	traceEvent(traceEvGCSTWDone, -1)
-}
-
-// traceGCSweepStart prepares to trace a sweep loop. This does not
-// emit any events until traceGCSweepSpan is called.
-//
-// traceGCSweepStart must be paired with traceGCSweepDone and there
-// must be no preemption points between these two calls.
-func traceGCSweepStart() {
-	// Delay the actual GCSweepStart event until the first span
-	// sweep. If we don't sweep anything, don't emit any events.
-	_p_ := getg().m.p.ptr()
-	if _p_.traceSweep {
-		throw("double traceGCSweepStart")
-	}
-	_p_.traceSweep, _p_.traceSwept, _p_.traceReclaimed = true, 0, 0
-}
-
-// traceGCSweepSpan traces the sweep of a single page.
-//
-// This may be called outside a traceGCSweepStart/traceGCSweepDone
-// pair; however, it will not emit any trace events in this case.
-func traceGCSweepSpan(bytesSwept uintptr) {
-	_p_ := getg().m.p.ptr()
-	if _p_.traceSweep {
-		if _p_.traceSwept == 0 {
-			traceEvent(traceEvGCSweepStart, 1)
-		}
-		_p_.traceSwept += bytesSwept
-	}
-}
-
-func traceGCSweepDone() {
-	_p_ := getg().m.p.ptr()
-	if !_p_.traceSweep {
-		throw("missing traceGCSweepStart")
-	}
-	if _p_.traceSwept != 0 {
-		traceEvent(traceEvGCSweepDone, -1, uint64(_p_.traceSwept), uint64(_p_.traceReclaimed))
-	}
-	_p_.traceSweep = false
-}
-
-func traceGCMarkAssistStart() {
-	traceEvent(traceEvGCMarkAssistStart, 1)
-}
-
-func traceGCMarkAssistDone() {
-	traceEvent(traceEvGCMarkAssistDone, -1)
-}
-
-func traceGoCreate(newg *g, pc uintptr) {
-	newg.traceseq = 0
-	newg.tracelastp = getg().m.p
-	// +PCQuantum because traceFrameForPC expects return PCs and subtracts PCQuantum.
-	id := trace.stackTab.put([]uintptr{startPCforTrace(pc) + sys.PCQuantum})
-	traceEvent(traceEvGoCreate, 2, uint64(newg.goid), uint64(id))
-}
-
-func traceGoStart() {
-	_g_ := getg().m.curg
-	_p_ := _g_.m.p
-	_g_.traceseq++
-	if _p_.ptr().gcMarkWorkerMode != gcMarkWorkerNotWorker {
-		traceEvent(traceEvGoStartLabel, -1, uint64(_g_.goid), _g_.traceseq, trace.markWorkerLabels[_p_.ptr().gcMarkWorkerMode])
-	} else if _g_.tracelastp == _p_ {
-		traceEvent(traceEvGoStartLocal, -1, uint64(_g_.goid))
-	} else {
-		_g_.tracelastp = _p_
-		traceEvent(traceEvGoStart, -1, uint64(_g_.goid), _g_.traceseq)
-	}
-}
-
-func traceGoEnd() {
-	traceEvent(traceEvGoEnd, -1)
-}
-
-func traceGoSched() {
-	_g_ := getg()
-	_g_.tracelastp = _g_.m.p
-	traceEvent(traceEvGoSched, 1)
-}
-
-func traceGoPreempt() {
-	_g_ := getg()
-	_g_.tracelastp = _g_.m.p
-	traceEvent(traceEvGoPreempt, 1)
-}
-
-func traceGoPark(traceEv byte, skip int) {
-	if traceEv&traceFutileWakeup != 0 {
-		traceEvent(traceEvFutileWakeup, -1)
-	}
-	traceEvent(traceEv & ^traceFutileWakeup, skip)
-}
-
-func traceGoUnpark(gp *g, skip int) {
-	_p_ := getg().m.p
-	gp.traceseq++
-	if gp.tracelastp == _p_ {
-		traceEvent(traceEvGoUnblockLocal, skip, uint64(gp.goid))
-	} else {
-		gp.tracelastp = _p_
-		traceEvent(traceEvGoUnblock, skip, uint64(gp.goid), gp.traceseq)
-	}
-}
-
-func traceGoSysCall() {
-	traceEvent(traceEvGoSysCall, 1)
-}
-
-func traceGoSysExit(ts int64) {
-	if ts != 0 && ts < trace.ticksStart {
-		// There is a race between the code that initializes sysexitticks
-		// (in exitsyscall, which runs without a P, and therefore is not
-		// stopped with the rest of the world) and the code that initializes
-		// a new trace. The recorded sysexitticks must therefore be treated
-		// as "best effort". If they are valid for this trace, then great,
-		// use them for greater accuracy. But if they're not valid for this
-		// trace, assume that the trace was started after the actual syscall
-		// exit (but before we actually managed to start the goroutine,
-		// aka right now), and assign a fresh time stamp to keep the log consistent.
-		ts = 0
-	}
-	_g_ := getg().m.curg
-	_g_.traceseq++
-	_g_.tracelastp = _g_.m.p
-	traceEvent(traceEvGoSysExit, -1, uint64(_g_.goid), _g_.traceseq, uint64(ts)/traceTickDiv)
-}
-
-func traceGoSysBlock(pp *p) {
-	// Sysmon and stopTheWorld can declare syscalls running on remote Ps as blocked,
-	// to handle this we temporary employ the P.
-	mp := acquirem()
-	oldp := mp.p
-	mp.p.set(pp)
-	traceEvent(traceEvGoSysBlock, -1)
-	mp.p = oldp
-	releasem(mp)
-}
-
-func traceHeapAlloc() {
-	traceEvent(traceEvHeapAlloc, -1, gcController.heapLive)
-}
-
-func traceHeapGoal() {
-	if heapGoal := atomic.Load64(&gcController.heapGoal); heapGoal == ^uint64(0) {
-		// Heap-based triggering is disabled.
-		traceEvent(traceEvHeapGoal, -1, 0)
-	} else {
-		traceEvent(traceEvHeapGoal, -1, heapGoal)
-	}
-}
-
-// To access runtime functions from runtime/trace.
-// See runtime/trace/annotation.go
-
-//go:linkname trace_userTaskCreate runtime/trace.userTaskCreate
-func trace_userTaskCreate(id, parentID uint64, taskType string) {
-	if !trace.enabled {
-		return
-	}
-
-	// Same as in traceEvent.
-	mp, pid, bufp := traceAcquireBuffer()
-	if !trace.enabled && !mp.startingtrace {
-		traceReleaseBuffer(pid)
-		return
-	}
-
-	typeStringID, bufp := traceString(bufp, pid, taskType)
-	traceEventLocked(0, mp, pid, bufp, traceEvUserTaskCreate, 3, id, parentID, typeStringID)
-	traceReleaseBuffer(pid)
-}
-
-//go:linkname trace_userTaskEnd runtime/trace.userTaskEnd
-func trace_userTaskEnd(id uint64) {
-	traceEvent(traceEvUserTaskEnd, 2, id)
-}
-
-//go:linkname trace_userRegion runtime/trace.userRegion
-func trace_userRegion(id, mode uint64, name string) {
-	if !trace.enabled {
-		return
-	}
-
-	mp, pid, bufp := traceAcquireBuffer()
-	if !trace.enabled && !mp.startingtrace {
-		traceReleaseBuffer(pid)
-		return
-	}
-
-	nameStringID, bufp := traceString(bufp, pid, name)
-	traceEventLocked(0, mp, pid, bufp, traceEvUserRegion, 3, id, mode, nameStringID)
-	traceReleaseBuffer(pid)
-}
-
-//go:linkname trace_userLog runtime/trace.userLog
-func trace_userLog(id uint64, category, message string) {
-	if !trace.enabled {
-		return
-	}
-
-	mp, pid, bufp := traceAcquireBuffer()
-	if !trace.enabled && !mp.startingtrace {
-		traceReleaseBuffer(pid)
-		return
-	}
-
-	categoryID, bufp := traceString(bufp, pid, category)
-
-	extraSpace := traceBytesPerNumber + len(message) // extraSpace for the value string
-	traceEventLocked(extraSpace, mp, pid, bufp, traceEvUserLog, 3, id, categoryID)
-	// traceEventLocked reserved extra space for val and len(val)
-	// in buf, so buf now has room for the following.
-	buf := bufp.ptr()
-
-	// double-check the message and its length can fit.
-	// Otherwise, truncate the message.
-	slen := len(message)
-	if room := len(buf.arr) - buf.pos; room < slen+traceBytesPerNumber {
-		slen = room
-	}
-	buf.varint(uint64(slen))
-	buf.pos += copy(buf.arr[buf.pos:], message[:slen])
-
-	traceReleaseBuffer(pid)
-}
-
-// the start PC of a goroutine for tracing purposes. If pc is a wrapper,
-// it returns the PC of the wrapped function. Otherwise it returns pc.
-func startPCforTrace(pc uintptr) uintptr {
-	f := findfunc(pc)
-	if !f.valid() {
-		return pc // should not happen, but don't care
-	}
-	w := funcdata(f, _FUNCDATA_WrapInfo)
-	if w == nil {
-		return pc // not a wrapper
-	}
-	return f.datap.textAddr(*(*uint32)(w))
-}
diff --git a/contrib/go/_std_1.18/src/runtime/traceback.go b/contrib/go/_std_1.18/src/runtime/traceback.go
deleted file mode 100644
index 229e3a9105..0000000000
--- a/contrib/go/_std_1.18/src/runtime/traceback.go
+++ /dev/null
@@ -1,1436 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package runtime
-
-import (
-	"internal/bytealg"
-	"internal/goarch"
-	"runtime/internal/atomic"
-	"runtime/internal/sys"
-	"unsafe"
-)
-
-// The code in this file implements stack trace walking for all architectures.
-// The most important fact about a given architecture is whether it uses a link register.
-// On systems with link registers, the prologue for a non-leaf function stores the
-// incoming value of LR at the bottom of the newly allocated stack frame.
-// On systems without link registers (x86), the architecture pushes a return PC during
-// the call instruction, so the return PC ends up above the stack frame.
-// In this file, the return PC is always called LR, no matter how it was found.
-
-const usesLR = sys.MinFrameSize > 0
-
-// Generic traceback. Handles runtime stack prints (pcbuf == nil),
-// the runtime.Callers function (pcbuf != nil), as well as the garbage
-// collector (callback != nil).  A little clunky to merge these, but avoids
-// duplicating the code and all its subtlety.
-//
-// The skip argument is only valid with pcbuf != nil and counts the number
-// of logical frames to skip rather than physical frames (with inlining, a
-// PC in pcbuf can represent multiple calls).
-func gentraceback(pc0, sp0, lr0 uintptr, gp *g, skip int, pcbuf *uintptr, max int, callback func(*stkframe, unsafe.Pointer) bool, v unsafe.Pointer, flags uint) int {
-	if skip > 0 && callback != nil {
-		throw("gentraceback callback cannot be used with non-zero skip")
-	}
-
-	// Don't call this "g"; it's too easy get "g" and "gp" confused.
-	if ourg := getg(); ourg == gp && ourg == ourg.m.curg {
-		// The starting sp has been passed in as a uintptr, and the caller may
-		// have other uintptr-typed stack references as well.
-		// If during one of the calls that got us here or during one of the
-		// callbacks below the stack must be grown, all these uintptr references
-		// to the stack will not be updated, and gentraceback will continue
-		// to inspect the old stack memory, which may no longer be valid.
-		// Even if all the variables were updated correctly, it is not clear that
-		// we want to expose a traceback that begins on one stack and ends
-		// on another stack. That could confuse callers quite a bit.
-		// Instead, we require that gentraceback and any other function that
-		// accepts an sp for the current goroutine (typically obtained by
-		// calling getcallersp) must not run on that goroutine's stack but
-		// instead on the g0 stack.
-		throw("gentraceback cannot trace user goroutine on its own stack")
-	}
-	level, _, _ := gotraceback()
-
-	var ctxt *funcval // Context pointer for unstarted goroutines. See issue #25897.
-
-	if pc0 == ^uintptr(0) && sp0 == ^uintptr(0) { // Signal to fetch saved values from gp.
-		if gp.syscallsp != 0 {
-			pc0 = gp.syscallpc
-			sp0 = gp.syscallsp
-			if usesLR {
-				lr0 = 0
-			}
-		} else {
-			pc0 = gp.sched.pc
-			sp0 = gp.sched.sp
-			if usesLR {
-				lr0 = gp.sched.lr
-			}
-			ctxt = (*funcval)(gp.sched.ctxt)
-		}
-	}
-
-	nprint := 0
-	var frame stkframe
-	frame.pc = pc0
-	frame.sp = sp0
-	if usesLR {
-		frame.lr = lr0
-	}
-	waspanic := false
-	cgoCtxt := gp.cgoCtxt
-	printing := pcbuf == nil && callback == nil
-
-	// If the PC is zero, it's likely a nil function call.
-	// Start in the caller's frame.
-	if frame.pc == 0 {
-		if usesLR {
-			frame.pc = *(*uintptr)(unsafe.Pointer(frame.sp))
-			frame.lr = 0
-		} else {
-			frame.pc = uintptr(*(*uintptr)(unsafe.Pointer(frame.sp)))
-			frame.sp += goarch.PtrSize
-		}
-	}
-
-	// runtime/internal/atomic functions call into kernel helpers on
-	// arm < 7. See runtime/internal/atomic/sys_linux_arm.s.
-	//
-	// Start in the caller's frame.
-	if GOARCH == "arm" && goarm < 7 && GOOS == "linux" && frame.pc&0xffff0000 == 0xffff0000 {
-		// Note that the calls are simple BL without pushing the return
-		// address, so we use LR directly.
-		//
-		// The kernel helpers are frameless leaf functions, so SP and
-		// LR are not touched.
-		frame.pc = frame.lr
-		frame.lr = 0
-	}
-
-	f := findfunc(frame.pc)
-	if !f.valid() {
-		if callback != nil || printing {
-			print("runtime: unknown pc ", hex(frame.pc), "\n")
-			tracebackHexdump(gp.stack, &frame, 0)
-		}
-		if callback != nil {
-			throw("unknown pc")
-		}
-		return 0
-	}
-	frame.fn = f
-
-	var cache pcvalueCache
-
-	lastFuncID := funcID_normal
-	n := 0
-	for n < max {
-		// Typically:
-		//	pc is the PC of the running function.
-		//	sp is the stack pointer at that program counter.
-		//	fp is the frame pointer (caller's stack pointer) at that program counter, or nil if unknown.
-		//	stk is the stack containing sp.
-		//	The caller's program counter is lr, unless lr is zero, in which case it is *(uintptr*)sp.
-		f = frame.fn
-		if f.pcsp == 0 {
-			// No frame information, must be external function, like race support.
-			// See golang.org/issue/13568.
-			break
-		}
-
-		// Compute function info flags.
-		flag := f.flag
-		if f.funcID == funcID_cgocallback {
-			// cgocallback does write SP to switch from the g0 to the curg stack,
-			// but it carefully arranges that during the transition BOTH stacks
-			// have cgocallback frame valid for unwinding through.
-			// So we don't need to exclude it with the other SP-writing functions.
-			flag &^= funcFlag_SPWRITE
-		}
-		if frame.pc == pc0 && frame.sp == sp0 && pc0 == gp.syscallpc && sp0 == gp.syscallsp {
-			// Some Syscall functions write to SP, but they do so only after
-			// saving the entry PC/SP using entersyscall.
-			// Since we are using the entry PC/SP, the later SP write doesn't matter.
-			flag &^= funcFlag_SPWRITE
-		}
-
-		// Found an actual function.
-		// Derive frame pointer and link register.
-		if frame.fp == 0 {
-			// Jump over system stack transitions. If we're on g0 and there's a user
-			// goroutine, try to jump. Otherwise this is a regular call.
-			if flags&_TraceJumpStack != 0 && gp == gp.m.g0 && gp.m.curg != nil {
-				switch f.funcID {
-				case funcID_morestack:
-					// morestack does not return normally -- newstack()
-					// gogo's to curg.sched. Match that.
-					// This keeps morestack() from showing up in the backtrace,
-					// but that makes some sense since it'll never be returned
-					// to.
-					frame.pc = gp.m.curg.sched.pc
-					frame.fn = findfunc(frame.pc)
-					f = frame.fn
-					flag = f.flag
-					frame.sp = gp.m.curg.sched.sp
-					cgoCtxt = gp.m.curg.cgoCtxt
-				case funcID_systemstack:
-					// systemstack returns normally, so just follow the
-					// stack transition.
-					frame.sp = gp.m.curg.sched.sp
-					cgoCtxt = gp.m.curg.cgoCtxt
-					flag &^= funcFlag_SPWRITE
-				}
-			}
-			frame.fp = frame.sp + uintptr(funcspdelta(f, frame.pc, &cache))
-			if !usesLR {
-				// On x86, call instruction pushes return PC before entering new function.
-				frame.fp += goarch.PtrSize
-			}
-		}
-		var flr funcInfo
-		if flag&funcFlag_TOPFRAME != 0 {
-			// This function marks the top of the stack. Stop the traceback.
-			frame.lr = 0
-			flr = funcInfo{}
-		} else if flag&funcFlag_SPWRITE != 0 && (callback == nil || n > 0) {
-			// The function we are in does a write to SP that we don't know
-			// how to encode in the spdelta table. Examples include context
-			// switch routines like runtime.gogo but also any code that switches
-			// to the g0 stack to run host C code. Since we can't reliably unwind
-			// the SP (we might not even be on the stack we think we are),
-			// we stop the traceback here.
-			// This only applies for profiling signals (callback == nil).
-			//
-			// For a GC stack traversal (callback != nil), we should only see
-			// a function when it has voluntarily preempted itself on entry
-			// during the stack growth check. In that case, the function has
-			// not yet had a chance to do any writes to SP and is safe to unwind.
-			// isAsyncSafePoint does not allow assembly functions to be async preempted,
-			// and preemptPark double-checks that SPWRITE functions are not async preempted.
-			// So for GC stack traversal we leave things alone (this if body does not execute for n == 0)
-			// at the bottom frame of the stack. But farther up the stack we'd better not
-			// find any.
-			if callback != nil {
-				println("traceback: unexpected SPWRITE function", funcname(f))
-				throw("traceback")
-			}
-			frame.lr = 0
-			flr = funcInfo{}
-		} else {
-			var lrPtr uintptr
-			if usesLR {
-				if n == 0 && frame.sp < frame.fp || frame.lr == 0 {
-					lrPtr = frame.sp
-					frame.lr = *(*uintptr)(unsafe.Pointer(lrPtr))
-				}
-			} else {
-				if frame.lr == 0 {
-					lrPtr = frame.fp - goarch.PtrSize
-					frame.lr = uintptr(*(*uintptr)(unsafe.Pointer(lrPtr)))
-				}
-			}
-			flr = findfunc(frame.lr)
-			if !flr.valid() {
-				// This happens if you get a profiling interrupt at just the wrong time.
-				// In that context it is okay to stop early.
-				// But if callback is set, we're doing a garbage collection and must
-				// get everything, so crash loudly.
-				doPrint := printing
-				if doPrint && gp.m.incgo && f.funcID == funcID_sigpanic {
-					// We can inject sigpanic
-					// calls directly into C code,
-					// in which case we'll see a C
-					// return PC. Don't complain.
-					doPrint = false
-				}
-				if callback != nil || doPrint {
-					print("runtime: unexpected return pc for ", funcname(f), " called from ", hex(frame.lr), "\n")
-					tracebackHexdump(gp.stack, &frame, lrPtr)
-				}
-				if callback != nil {
-					throw("unknown caller pc")
-				}
-			}
-		}
-
-		frame.varp = frame.fp
-		if !usesLR {
-			// On x86, call instruction pushes return PC before entering new function.
-			frame.varp -= goarch.PtrSize
-		}
-
-		// For architectures with frame pointers, if there's
-		// a frame, then there's a saved frame pointer here.
-		//
-		// NOTE: This code is not as general as it looks.
-		// On x86, the ABI is to save the frame pointer word at the
-		// top of the stack frame, so we have to back down over it.
-		// On arm64, the frame pointer should be at the bottom of
-		// the stack (with R29 (aka FP) = RSP), in which case we would
-		// not want to do the subtraction here. But we started out without
-		// any frame pointer, and when we wanted to add it, we didn't
-		// want to break all the assembly doing direct writes to 8(RSP)
-		// to set the first parameter to a called function.
-		// So we decided to write the FP link *below* the stack pointer
-		// (with R29 = RSP - 8 in Go functions).
-		// This is technically ABI-compatible but not standard.
-		// And it happens to end up mimicking the x86 layout.
-		// Other architectures may make different decisions.
-		if frame.varp > frame.sp && framepointer_enabled {
-			frame.varp -= goarch.PtrSize
-		}
-
-		// Derive size of arguments.
-		// Most functions have a fixed-size argument block,
-		// so we can use metadata about the function f.
-		// Not all, though: there are some variadic functions
-		// in package runtime and reflect, and for those we use call-specific
-		// metadata recorded by f's caller.
-		if callback != nil || printing {
-			frame.argp = frame.fp + sys.MinFrameSize
-			var ok bool
-			frame.arglen, frame.argmap, ok = getArgInfoFast(f, callback != nil)
-			if !ok {
-				frame.arglen, frame.argmap = getArgInfo(&frame, f, callback != nil, ctxt)
-			}
-		}
-		ctxt = nil // ctxt is only needed to get arg maps for the topmost frame
-
-		// Determine frame's 'continuation PC', where it can continue.
-		// Normally this is the return address on the stack, but if sigpanic
-		// is immediately below this function on the stack, then the frame
-		// stopped executing due to a trap, and frame.pc is probably not
-		// a safe point for looking up liveness information. In this panicking case,
-		// the function either doesn't return at all (if it has no defers or if the
-		// defers do not recover) or it returns from one of the calls to
-		// deferproc a second time (if the corresponding deferred func recovers).
-		// In the latter case, use a deferreturn call site as the continuation pc.
-		frame.continpc = frame.pc
-		if waspanic {
-			if frame.fn.deferreturn != 0 {
-				frame.continpc = frame.fn.entry() + uintptr(frame.fn.deferreturn) + 1
-				// Note: this may perhaps keep return variables alive longer than
-				// strictly necessary, as we are using "function has a defer statement"
-				// as a proxy for "function actually deferred something". It seems
-				// to be a minor drawback. (We used to actually look through the
-				// gp._defer for a defer corresponding to this function, but that
-				// is hard to do with defer records on the stack during a stack copy.)
-				// Note: the +1 is to offset the -1 that
-				// stack.go:getStackMap does to back up a return
-				// address make sure the pc is in the CALL instruction.
-			} else {
-				frame.continpc = 0
-			}
-		}
-
-		if callback != nil {
-			if !callback((*stkframe)(noescape(unsafe.Pointer(&frame))), v) {
-				return n
-			}
-		}
-
-		if pcbuf != nil {
-			pc := frame.pc
-			// backup to CALL instruction to read inlining info (same logic as below)
-			tracepc := pc
-			// Normally, pc is a return address. In that case, we want to look up
-			// file/line information using pc-1, because that is the pc of the
-			// call instruction (more precisely, the last byte of the call instruction).
-			// Callers expect the pc buffer to contain return addresses and do the
-			// same -1 themselves, so we keep pc unchanged.
-			// When the pc is from a signal (e.g. profiler or segv) then we want
-			// to look up file/line information using pc, and we store pc+1 in the
-			// pc buffer so callers can unconditionally subtract 1 before looking up.
-			// See issue 34123.
-			// The pc can be at function entry when the frame is initialized without
-			// actually running code, like runtime.mstart.
-			if (n == 0 && flags&_TraceTrap != 0) || waspanic || pc == f.entry() {
-				pc++
-			} else {
-				tracepc--
-			}
-
-			// If there is inlining info, record the inner frames.
-			if inldata := funcdata(f, _FUNCDATA_InlTree); inldata != nil {
-				inltree := (*[1 << 20]inlinedCall)(inldata)
-				for {
-					ix := pcdatavalue(f, _PCDATA_InlTreeIndex, tracepc, &cache)
-					if ix < 0 {
-						break
-					}
-					if inltree[ix].funcID == funcID_wrapper && elideWrapperCalling(lastFuncID) {
-						// ignore wrappers
-					} else if skip > 0 {
-						skip--
-					} else if n < max {
-						(*[1 << 20]uintptr)(unsafe.Pointer(pcbuf))[n] = pc
-						n++
-					}
-					lastFuncID = inltree[ix].funcID
-					// Back up to an instruction in the "caller".
-					tracepc = frame.fn.entry() + uintptr(inltree[ix].parentPc)
-					pc = tracepc + 1
-				}
-			}
-			// Record the main frame.
-			if f.funcID == funcID_wrapper && elideWrapperCalling(lastFuncID) {
-				// Ignore wrapper functions (except when they trigger panics).
-			} else if skip > 0 {
-				skip--
-			} else if n < max {
-				(*[1 << 20]uintptr)(unsafe.Pointer(pcbuf))[n] = pc
-				n++
-			}
-			lastFuncID = f.funcID
-			n-- // offset n++ below
-		}
-
-		if printing {
-			// assume skip=0 for printing.
-			//
-			// Never elide wrappers if we haven't printed
-			// any frames. And don't elide wrappers that
-			// called panic rather than the wrapped
-			// function. Otherwise, leave them out.
-
-			// backup to CALL instruction to read inlining info (same logic as below)
-			tracepc := frame.pc
-			if (n > 0 || flags&_TraceTrap == 0) && frame.pc > f.entry() && !waspanic {
-				tracepc--
-			}
-			// If there is inlining info, print the inner frames.
-			if inldata := funcdata(f, _FUNCDATA_InlTree); inldata != nil {
-				inltree := (*[1 << 20]inlinedCall)(inldata)
-				var inlFunc _func
-				inlFuncInfo := funcInfo{&inlFunc, f.datap}
-				for {
-					ix := pcdatavalue(f, _PCDATA_InlTreeIndex, tracepc, nil)
-					if ix < 0 {
-						break
-					}
-
-					// Create a fake _func for the
-					// inlined function.
-					inlFunc.nameoff = inltree[ix].func_
-					inlFunc.funcID = inltree[ix].funcID
-
-					if (flags&_TraceRuntimeFrames) != 0 || showframe(inlFuncInfo, gp, nprint == 0, inlFuncInfo.funcID, lastFuncID) {
-						name := funcname(inlFuncInfo)
-						file, line := funcline(f, tracepc)
-						print(name, "(...)\n")
-						print("\t", file, ":", line, "\n")
-						nprint++
-					}
-					lastFuncID = inltree[ix].funcID
-					// Back up to an instruction in the "caller".
-					tracepc = frame.fn.entry() + uintptr(inltree[ix].parentPc)
-				}
-			}
-			if (flags&_TraceRuntimeFrames) != 0 || showframe(f, gp, nprint == 0, f.funcID, lastFuncID) {
-				// Print during crash.
-				//	main(0x1, 0x2, 0x3)
-				//		/home/rsc/go/src/runtime/x.go:23 +0xf
-				//
-				name := funcname(f)
-				file, line := funcline(f, tracepc)
-				if name == "runtime.gopanic" {
-					name = "panic"
-				}
-				print(name, "(")
-				argp := unsafe.Pointer(frame.argp)
-				printArgs(f, argp, tracepc)
-				print(")\n")
-				print("\t", file, ":", line)
-				if frame.pc > f.entry() {
-					print(" +", hex(frame.pc-f.entry()))
-				}
-				if gp.m != nil && gp.m.throwing > 0 && gp == gp.m.curg || level >= 2 {
-					print(" fp=", hex(frame.fp), " sp=", hex(frame.sp), " pc=", hex(frame.pc))
-				}
-				print("\n")
-				nprint++
-			}
-			lastFuncID = f.funcID
-		}
-		n++
-
-		if f.funcID == funcID_cgocallback && len(cgoCtxt) > 0 {
-			ctxt := cgoCtxt[len(cgoCtxt)-1]
-			cgoCtxt = cgoCtxt[:len(cgoCtxt)-1]
-
-			// skip only applies to Go frames.
-			// callback != nil only used when we only care
-			// about Go frames.
-			if skip == 0 && callback == nil {
-				n = tracebackCgoContext(pcbuf, printing, ctxt, n, max)
-			}
-		}
-
-		waspanic = f.funcID == funcID_sigpanic
-		injectedCall := waspanic || f.funcID == funcID_asyncPreempt || f.funcID == funcID_debugCallV2
-
-		// Do not unwind past the bottom of the stack.
-		if !flr.valid() {
-			break
-		}
-
-		// Unwind to next frame.
-		frame.fn = flr
-		frame.pc = frame.lr
-		frame.lr = 0
-		frame.sp = frame.fp
-		frame.fp = 0
-		frame.argmap = nil
-
-		// On link register architectures, sighandler saves the LR on stack
-		// before faking a call.
-		if usesLR && injectedCall {
-			x := *(*uintptr)(unsafe.Pointer(frame.sp))
-			frame.sp += alignUp(sys.MinFrameSize, sys.StackAlign)
-			f = findfunc(frame.pc)
-			frame.fn = f
-			if !f.valid() {
-				frame.pc = x
-			} else if funcspdelta(f, frame.pc, &cache) == 0 {
-				frame.lr = x
-			}
-		}
-	}
-
-	if printing {
-		n = nprint
-	}
-
-	// Note that panic != nil is okay here: there can be leftover panics,
-	// because the defers on the panic stack do not nest in frame order as
-	// they do on the defer stack. If you have:
-	//
-	//	frame 1 defers d1
-	//	frame 2 defers d2
-	//	frame 3 defers d3
-	//	frame 4 panics
-	//	frame 4's panic starts running defers
-	//	frame 5, running d3, defers d4
-	//	frame 5 panics
-	//	frame 5's panic starts running defers
-	//	frame 6, running d4, garbage collects
-	//	frame 6, running d2, garbage collects
-	//
-	// During the execution of d4, the panic stack is d4 -> d3, which
-	// is nested properly, and we'll treat frame 3 as resumable, because we
-	// can find d3. (And in fact frame 3 is resumable. If d4 recovers
-	// and frame 5 continues running, d3, d3 can recover and we'll
-	// resume execution in (returning from) frame 3.)
-	//
-	// During the execution of d2, however, the panic stack is d2 -> d3,
-	// which is inverted. The scan will match d2 to frame 2 but having
-	// d2 on the stack until then means it will not match d3 to frame 3.
-	// This is okay: if we're running d2, then all the defers after d2 have
-	// completed and their corresponding frames are dead. Not finding d3
-	// for frame 3 means we'll set frame 3's continpc == 0, which is correct
-	// (frame 3 is dead). At the end of the walk the panic stack can thus
-	// contain defers (d3 in this case) for dead frames. The inversion here
-	// always indicates a dead frame, and the effect of the inversion on the
-	// scan is to hide those dead frames, so the scan is still okay:
-	// what's left on the panic stack are exactly (and only) the dead frames.
-	//
-	// We require callback != nil here because only when callback != nil
-	// do we know that gentraceback is being called in a "must be correct"
-	// context as opposed to a "best effort" context. The tracebacks with
-	// callbacks only happen when everything is stopped nicely.
-	// At other times, such as when gathering a stack for a profiling signal
-	// or when printing a traceback during a crash, everything may not be
-	// stopped nicely, and the stack walk may not be able to complete.
-	if callback != nil && n < max && frame.sp != gp.stktopsp {
-		print("runtime: g", gp.goid, ": frame.sp=", hex(frame.sp), " top=", hex(gp.stktopsp), "\n")
-		print("\tstack=[", hex(gp.stack.lo), "-", hex(gp.stack.hi), "] n=", n, " max=", max, "\n")
-		throw("traceback did not unwind completely")
-	}
-
-	return n
-}
-
-// printArgs prints function arguments in traceback.
-func printArgs(f funcInfo, argp unsafe.Pointer, pc uintptr) {
-	// The "instruction" of argument printing is encoded in _FUNCDATA_ArgInfo.
-	// See cmd/compile/internal/ssagen.emitArgInfo for the description of the
-	// encoding.
-	// These constants need to be in sync with the compiler.
-	const (
-		_endSeq         = 0xff
-		_startAgg       = 0xfe
-		_endAgg         = 0xfd
-		_dotdotdot      = 0xfc
-		_offsetTooLarge = 0xfb
-	)
-
-	const (
-		limit    = 10                       // print no more than 10 args/components
-		maxDepth = 5                        // no more than 5 layers of nesting
-		maxLen   = (maxDepth*3+2)*limit + 1 // max length of _FUNCDATA_ArgInfo (see the compiler side for reasoning)
-	)
-
-	p := (*[maxLen]uint8)(funcdata(f, _FUNCDATA_ArgInfo))
-	if p == nil {
-		return
-	}
-
-	liveInfo := funcdata(f, _FUNCDATA_ArgLiveInfo)
-	liveIdx := pcdatavalue(f, _PCDATA_ArgLiveIndex, pc, nil)
-	startOffset := uint8(0xff) // smallest offset that needs liveness info (slots with a lower offset is always live)
-	if liveInfo != nil {
-		startOffset = *(*uint8)(liveInfo)
-	}
-
-	isLive := func(off, slotIdx uint8) bool {
-		if liveInfo == nil || liveIdx <= 0 {
-			return true // no liveness info, always live
-		}
-		if off < startOffset {
-			return true
-		}
-		bits := *(*uint8)(add(liveInfo, uintptr(liveIdx)+uintptr(slotIdx/8)))
-		return bits&(1<<(slotIdx%8)) != 0
-	}
-
-	print1 := func(off, sz, slotIdx uint8) {
-		x := readUnaligned64(add(argp, uintptr(off)))
-		// mask out irrelevant bits
-		if sz < 8 {
-			shift := 64 - sz*8
-			if goarch.BigEndian {
-				x = x >> shift
-			} else {
-				x = x << shift >> shift
-			}
-		}
-		print(hex(x))
-		if !isLive(off, slotIdx) {
-			print("?")
-		}
-	}
-
-	start := true
-	printcomma := func() {
-		if !start {
-			print(", ")
-		}
-	}
-	pi := 0
-	slotIdx := uint8(0) // register arg spill slot index
-printloop:
-	for {
-		o := p[pi]
-		pi++
-		switch o {
-		case _endSeq:
-			break printloop
-		case _startAgg:
-			printcomma()
-			print("{")
-			start = true
-			continue
-		case _endAgg:
-			print("}")
-		case _dotdotdot:
-			printcomma()
-			print("...")
-		case _offsetTooLarge:
-			printcomma()
-			print("_")
-		default:
-			printcomma()
-			sz := p[pi]
-			pi++
-			print1(o, sz, slotIdx)
-			if o >= startOffset {
-				slotIdx++
-			}
-		}
-		start = false
-	}
-}
-
-// reflectMethodValue is a partial duplicate of reflect.makeFuncImpl
-// and reflect.methodValue.
-type reflectMethodValue struct {
-	fn     uintptr
-	stack  *bitvector // ptrmap for both args and results
-	argLen uintptr    // just args
-}
-
-// getArgInfoFast returns the argument frame information for a call to f.
-// It is short and inlineable. However, it does not handle all functions.
-// If ok reports false, you must call getArgInfo instead.
-// TODO(josharian): once we do mid-stack inlining,
-// call getArgInfo directly from getArgInfoFast and stop returning an ok bool.
-func getArgInfoFast(f funcInfo, needArgMap bool) (arglen uintptr, argmap *bitvector, ok bool) {
-	return uintptr(f.args), nil, !(needArgMap && f.args == _ArgsSizeUnknown)
-}
-
-// getArgInfo returns the argument frame information for a call to f
-// with call frame frame.
-//
-// This is used for both actual calls with active stack frames and for
-// deferred calls or goroutines that are not yet executing. If this is an actual
-// call, ctxt must be nil (getArgInfo will retrieve what it needs from
-// the active stack frame). If this is a deferred call or unstarted goroutine,
-// ctxt must be the function object that was deferred or go'd.
-func getArgInfo(frame *stkframe, f funcInfo, needArgMap bool, ctxt *funcval) (arglen uintptr, argmap *bitvector) {
-	arglen = uintptr(f.args)
-	if needArgMap && f.args == _ArgsSizeUnknown {
-		// Extract argument bitmaps for reflect stubs from the calls they made to reflect.
-		switch funcname(f) {
-		case "reflect.makeFuncStub", "reflect.methodValueCall":
-			// These take a *reflect.methodValue as their
-			// context register.
-			var mv *reflectMethodValue
-			var retValid bool
-			if ctxt != nil {
-				// This is not an actual call, but a
-				// deferred call or an unstarted goroutine.
-				// The function value is itself the *reflect.methodValue.
-				mv = (*reflectMethodValue)(unsafe.Pointer(ctxt))
-			} else {
-				// This is a real call that took the
-				// *reflect.methodValue as its context
-				// register and immediately saved it
-				// to 0(SP). Get the methodValue from
-				// 0(SP).
-				arg0 := frame.sp + sys.MinFrameSize
-				mv = *(**reflectMethodValue)(unsafe.Pointer(arg0))
-				// Figure out whether the return values are valid.
-				// Reflect will update this value after it copies
-				// in the return values.
-				retValid = *(*bool)(unsafe.Pointer(arg0 + 4*goarch.PtrSize))
-			}
-			if mv.fn != f.entry() {
-				print("runtime: confused by ", funcname(f), "\n")
-				throw("reflect mismatch")
-			}
-			bv := mv.stack
-			arglen = uintptr(bv.n * goarch.PtrSize)
-			if !retValid {
-				arglen = uintptr(mv.argLen) &^ (goarch.PtrSize - 1)
-			}
-			argmap = bv
-		}
-	}
-	return
-}
-
-// tracebackCgoContext handles tracing back a cgo context value, from
-// the context argument to setCgoTraceback, for the gentraceback
-// function. It returns the new value of n.
-func tracebackCgoContext(pcbuf *uintptr, printing bool, ctxt uintptr, n, max int) int {
-	var cgoPCs [32]uintptr
-	cgoContextPCs(ctxt, cgoPCs[:])
-	var arg cgoSymbolizerArg
-	anySymbolized := false
-	for _, pc := range cgoPCs {
-		if pc == 0 || n >= max {
-			break
-		}
-		if pcbuf != nil {
-			(*[1 << 20]uintptr)(unsafe.Pointer(pcbuf))[n] = pc
-		}
-		if printing {
-			if cgoSymbolizer == nil {
-				print("non-Go function at pc=", hex(pc), "\n")
-			} else {
-				c := printOneCgoTraceback(pc, max-n, &arg)
-				n += c - 1 // +1 a few lines down
-				anySymbolized = true
-			}
-		}
-		n++
-	}
-	if anySymbolized {
-		arg.pc = 0
-		callCgoSymbolizer(&arg)
-	}
-	return n
-}
-
-func printcreatedby(gp *g) {
-	// Show what created goroutine, except main goroutine (goid 1).
-	pc := gp.gopc
-	f := findfunc(pc)
-	if f.valid() && showframe(f, gp, false, funcID_normal, funcID_normal) && gp.goid != 1 {
-		printcreatedby1(f, pc)
-	}
-}
-
-func printcreatedby1(f funcInfo, pc uintptr) {
-	print("created by ", funcname(f), "\n")
-	tracepc := pc // back up to CALL instruction for funcline.
-	if pc > f.entry() {
-		tracepc -= sys.PCQuantum
-	}
-	file, line := funcline(f, tracepc)
-	print("\t", file, ":", line)
-	if pc > f.entry() {
-		print(" +", hex(pc-f.entry()))
-	}
-	print("\n")
-}
-
-func traceback(pc, sp, lr uintptr, gp *g) {
-	traceback1(pc, sp, lr, gp, 0)
-}
-
-// tracebacktrap is like traceback but expects that the PC and SP were obtained
-// from a trap, not from gp->sched or gp->syscallpc/gp->syscallsp or getcallerpc/getcallersp.
-// Because they are from a trap instead of from a saved pair,
-// the initial PC must not be rewound to the previous instruction.
-// (All the saved pairs record a PC that is a return address, so we
-// rewind it into the CALL instruction.)
-// If gp.m.libcall{g,pc,sp} information is available, it uses that information in preference to
-// the pc/sp/lr passed in.
-func tracebacktrap(pc, sp, lr uintptr, gp *g) {
-	if gp.m.libcallsp != 0 {
-		// We're in C code somewhere, traceback from the saved position.
-		traceback1(gp.m.libcallpc, gp.m.libcallsp, 0, gp.m.libcallg.ptr(), 0)
-		return
-	}
-	traceback1(pc, sp, lr, gp, _TraceTrap)
-}
-
-func traceback1(pc, sp, lr uintptr, gp *g, flags uint) {
-	// If the goroutine is in cgo, and we have a cgo traceback, print that.
-	if iscgo && gp.m != nil && gp.m.ncgo > 0 && gp.syscallsp != 0 && gp.m.cgoCallers != nil && gp.m.cgoCallers[0] != 0 {
-		// Lock cgoCallers so that a signal handler won't
-		// change it, copy the array, reset it, unlock it.
-		// We are locked to the thread and are not running
-		// concurrently with a signal handler.
-		// We just have to stop a signal handler from interrupting
-		// in the middle of our copy.
-		atomic.Store(&gp.m.cgoCallersUse, 1)
-		cgoCallers := *gp.m.cgoCallers
-		gp.m.cgoCallers[0] = 0
-		atomic.Store(&gp.m.cgoCallersUse, 0)
-
-		printCgoTraceback(&cgoCallers)
-	}
-
-	if readgstatus(gp)&^_Gscan == _Gsyscall {
-		// Override registers if blocked in system call.
-		pc = gp.syscallpc
-		sp = gp.syscallsp
-		flags &^= _TraceTrap
-	}
-	if gp.m != nil && gp.m.vdsoSP != 0 {
-		// Override registers if running in VDSO. This comes after the
-		// _Gsyscall check to cover VDSO calls after entersyscall.
-		pc = gp.m.vdsoPC
-		sp = gp.m.vdsoSP
-		flags &^= _TraceTrap
-	}
-
-	// Print traceback. By default, omits runtime frames.
-	// If that means we print nothing at all, repeat forcing all frames printed.
-	n := gentraceback(pc, sp, lr, gp, 0, nil, _TracebackMaxFrames, nil, nil, flags)
-	if n == 0 && (flags&_TraceRuntimeFrames) == 0 {
-		n = gentraceback(pc, sp, lr, gp, 0, nil, _TracebackMaxFrames, nil, nil, flags|_TraceRuntimeFrames)
-	}
-	if n == _TracebackMaxFrames {
-		print("...additional frames elided...\n")
-	}
-	printcreatedby(gp)
-
-	if gp.ancestors == nil {
-		return
-	}
-	for _, ancestor := range *gp.ancestors {
-		printAncestorTraceback(ancestor)
-	}
-}
-
-// printAncestorTraceback prints the traceback of the given ancestor.
-// TODO: Unify this with gentraceback and CallersFrames.
-func printAncestorTraceback(ancestor ancestorInfo) {
-	print("[originating from goroutine ", ancestor.goid, "]:\n")
-	for fidx, pc := range ancestor.pcs {
-		f := findfunc(pc) // f previously validated
-		if showfuncinfo(f, fidx == 0, funcID_normal, funcID_normal) {
-			printAncestorTracebackFuncInfo(f, pc)
-		}
-	}
-	if len(ancestor.pcs) == _TracebackMaxFrames {
-		print("...additional frames elided...\n")
-	}
-	// Show what created goroutine, except main goroutine (goid 1).
-	f := findfunc(ancestor.gopc)
-	if f.valid() && showfuncinfo(f, false, funcID_normal, funcID_normal) && ancestor.goid != 1 {
-		printcreatedby1(f, ancestor.gopc)
-	}
-}
-
-// printAncestorTraceback prints the given function info at a given pc
-// within an ancestor traceback. The precision of this info is reduced
-// due to only have access to the pcs at the time of the caller
-// goroutine being created.
-func printAncestorTracebackFuncInfo(f funcInfo, pc uintptr) {
-	name := funcname(f)
-	if inldata := funcdata(f, _FUNCDATA_InlTree); inldata != nil {
-		inltree := (*[1 << 20]inlinedCall)(inldata)
-		ix := pcdatavalue(f, _PCDATA_InlTreeIndex, pc, nil)
-		if ix >= 0 {
-			name = funcnameFromNameoff(f, inltree[ix].func_)
-		}
-	}
-	file, line := funcline(f, pc)
-	if name == "runtime.gopanic" {
-		name = "panic"
-	}
-	print(name, "(...)\n")
-	print("\t", file, ":", line)
-	if pc > f.entry() {
-		print(" +", hex(pc-f.entry()))
-	}
-	print("\n")
-}
-
-func callers(skip int, pcbuf []uintptr) int {
-	sp := getcallersp()
-	pc := getcallerpc()
-	gp := getg()
-	var n int
-	systemstack(func() {
-		n = gentraceback(pc, sp, 0, gp, skip, &pcbuf[0], len(pcbuf), nil, nil, 0)
-	})
-	return n
-}
-
-func gcallers(gp *g, skip int, pcbuf []uintptr) int {
-	return gentraceback(^uintptr(0), ^uintptr(0), 0, gp, skip, &pcbuf[0], len(pcbuf), nil, nil, 0)
-}
-
-// showframe reports whether the frame with the given characteristics should
-// be printed during a traceback.
-func showframe(f funcInfo, gp *g, firstFrame bool, funcID, childID funcID) bool {
-	g := getg()
-	if g.m.throwing > 0 && gp != nil && (gp == g.m.curg || gp == g.m.caughtsig.ptr()) {
-		return true
-	}
-	return showfuncinfo(f, firstFrame, funcID, childID)
-}
-
-// showfuncinfo reports whether a function with the given characteristics should
-// be printed during a traceback.
-func showfuncinfo(f funcInfo, firstFrame bool, funcID, childID funcID) bool {
-	// Note that f may be a synthesized funcInfo for an inlined
-	// function, in which case only nameoff and funcID are set.
-
-	level, _, _ := gotraceback()
-	if level > 1 {
-		// Show all frames.
-		return true
-	}
-
-	if !f.valid() {
-		return false
-	}
-
-	if funcID == funcID_wrapper && elideWrapperCalling(childID) {
-		return false
-	}
-
-	name := funcname(f)
-
-	// Special case: always show runtime.gopanic frame
-	// in the middle of a stack trace, so that we can
-	// see the boundary between ordinary code and
-	// panic-induced deferred code.
-	// See golang.org/issue/5832.
-	if name == "runtime.gopanic" && !firstFrame {
-		return true
-	}
-
-	return bytealg.IndexByteString(name, '.') >= 0 && (!hasPrefix(name, "runtime.") || isExportedRuntime(name))
-}
-
-// isExportedRuntime reports whether name is an exported runtime function.
-// It is only for runtime functions, so ASCII A-Z is fine.
-func isExportedRuntime(name string) bool {
-	const n = len("runtime.")
-	return len(name) > n && name[:n] == "runtime." && 'A' <= name[n] && name[n] <= 'Z'
-}
-
-// elideWrapperCalling reports whether a wrapper function that called
-// function id should be elided from stack traces.
-func elideWrapperCalling(id funcID) bool {
-	// If the wrapper called a panic function instead of the
-	// wrapped function, we want to include it in stacks.
-	return !(id == funcID_gopanic || id == funcID_sigpanic || id == funcID_panicwrap)
-}
-
-var gStatusStrings = [...]string{
-	_Gidle:      "idle",
-	_Grunnable:  "runnable",
-	_Grunning:   "running",
-	_Gsyscall:   "syscall",
-	_Gwaiting:   "waiting",
-	_Gdead:      "dead",
-	_Gcopystack: "copystack",
-	_Gpreempted: "preempted",
-}
-
-func goroutineheader(gp *g) {
-	gpstatus := readgstatus(gp)
-
-	isScan := gpstatus&_Gscan != 0
-	gpstatus &^= _Gscan // drop the scan bit
-
-	// Basic string status
-	var status string
-	if 0 <= gpstatus && gpstatus < uint32(len(gStatusStrings)) {
-		status = gStatusStrings[gpstatus]
-	} else {
-		status = "???"
-	}
-
-	// Override.
-	if gpstatus == _Gwaiting && gp.waitreason != waitReasonZero {
-		status = gp.waitreason.String()
-	}
-
-	// approx time the G is blocked, in minutes
-	var waitfor int64
-	if (gpstatus == _Gwaiting || gpstatus == _Gsyscall) && gp.waitsince != 0 {
-		waitfor = (nanotime() - gp.waitsince) / 60e9
-	}
-	print("goroutine ", gp.goid, " [", status)
-	if isScan {
-		print(" (scan)")
-	}
-	if waitfor >= 1 {
-		print(", ", waitfor, " minutes")
-	}
-	if gp.lockedm != 0 {
-		print(", locked to thread")
-	}
-	print("]:\n")
-}
-
-func tracebackothers(me *g) {
-	level, _, _ := gotraceback()
-
-	// Show the current goroutine first, if we haven't already.
-	curgp := getg().m.curg
-	if curgp != nil && curgp != me {
-		print("\n")
-		goroutineheader(curgp)
-		traceback(^uintptr(0), ^uintptr(0), 0, curgp)
-	}
-
-	// We can't call locking forEachG here because this may be during fatal
-	// throw/panic, where locking could be out-of-order or a direct
-	// deadlock.
-	//
-	// Instead, use forEachGRace, which requires no locking. We don't lock
-	// against concurrent creation of new Gs, but even with allglock we may
-	// miss Gs created after this loop.
-	forEachGRace(func(gp *g) {
-		if gp == me || gp == curgp || readgstatus(gp) == _Gdead || isSystemGoroutine(gp, false) && level < 2 {
-			return
-		}
-		print("\n")
-		goroutineheader(gp)
-		// Note: gp.m == g.m occurs when tracebackothers is
-		// called from a signal handler initiated during a
-		// systemstack call. The original G is still in the
-		// running state, and we want to print its stack.
-		if gp.m != getg().m && readgstatus(gp)&^_Gscan == _Grunning {
-			print("\tgoroutine running on other thread; stack unavailable\n")
-			printcreatedby(gp)
-		} else {
-			traceback(^uintptr(0), ^uintptr(0), 0, gp)
-		}
-	})
-}
-
-// tracebackHexdump hexdumps part of stk around frame.sp and frame.fp
-// for debugging purposes. If the address bad is included in the
-// hexdumped range, it will mark it as well.
-func tracebackHexdump(stk stack, frame *stkframe, bad uintptr) {
-	const expand = 32 * goarch.PtrSize
-	const maxExpand = 256 * goarch.PtrSize
-	// Start around frame.sp.
-	lo, hi := frame.sp, frame.sp
-	// Expand to include frame.fp.
-	if frame.fp != 0 && frame.fp < lo {
-		lo = frame.fp
-	}
-	if frame.fp != 0 && frame.fp > hi {
-		hi = frame.fp
-	}
-	// Expand a bit more.
-	lo, hi = lo-expand, hi+expand
-	// But don't go too far from frame.sp.
-	if lo < frame.sp-maxExpand {
-		lo = frame.sp - maxExpand
-	}
-	if hi > frame.sp+maxExpand {
-		hi = frame.sp + maxExpand
-	}
-	// And don't go outside the stack bounds.
-	if lo < stk.lo {
-		lo = stk.lo
-	}
-	if hi > stk.hi {
-		hi = stk.hi
-	}
-
-	// Print the hex dump.
-	print("stack: frame={sp:", hex(frame.sp), ", fp:", hex(frame.fp), "} stack=[", hex(stk.lo), ",", hex(stk.hi), ")\n")
-	hexdumpWords(lo, hi, func(p uintptr) byte {
-		switch p {
-		case frame.fp:
-			return '>'
-		case frame.sp:
-			return '<'
-		case bad:
-			return '!'
-		}
-		return 0
-	})
-}
-
-// isSystemGoroutine reports whether the goroutine g must be omitted
-// in stack dumps and deadlock detector. This is any goroutine that
-// starts at a runtime.* entry point, except for runtime.main,
-// runtime.handleAsyncEvent (wasm only) and sometimes runtime.runfinq.
-//
-// If fixed is true, any goroutine that can vary between user and
-// system (that is, the finalizer goroutine) is considered a user
-// goroutine.
-func isSystemGoroutine(gp *g, fixed bool) bool {
-	// Keep this in sync with cmd/trace/trace.go:isSystemGoroutine.
-	f := findfunc(gp.startpc)
-	if !f.valid() {
-		return false
-	}
-	if f.funcID == funcID_runtime_main || f.funcID == funcID_handleAsyncEvent {
-		return false
-	}
-	if f.funcID == funcID_runfinq {
-		// We include the finalizer goroutine if it's calling
-		// back into user code.
-		if fixed {
-			// This goroutine can vary. In fixed mode,
-			// always consider it a user goroutine.
-			return false
-		}
-		return !fingRunning
-	}
-	return hasPrefix(funcname(f), "runtime.")
-}
-
-// SetCgoTraceback records three C functions to use to gather
-// traceback information from C code and to convert that traceback
-// information into symbolic information. These are used when printing
-// stack traces for a program that uses cgo.
-//
-// The traceback and context functions may be called from a signal
-// handler, and must therefore use only async-signal safe functions.
-// The symbolizer function may be called while the program is
-// crashing, and so must be cautious about using memory.  None of the
-// functions may call back into Go.
-//
-// The context function will be called with a single argument, a
-// pointer to a struct:
-//
-//	struct {
-//		Context uintptr
-//	}
-//
-// In C syntax, this struct will be
-//
-//	struct {
-//		uintptr_t Context;
-//	};
-//
-// If the Context field is 0, the context function is being called to
-// record the current traceback context. It should record in the
-// Context field whatever information is needed about the current
-// point of execution to later produce a stack trace, probably the
-// stack pointer and PC. In this case the context function will be
-// called from C code.
-//
-// If the Context field is not 0, then it is a value returned by a
-// previous call to the context function. This case is called when the
-// context is no longer needed; that is, when the Go code is returning
-// to its C code caller. This permits the context function to release
-// any associated resources.
-//
-// While it would be correct for the context function to record a
-// complete a stack trace whenever it is called, and simply copy that
-// out in the traceback function, in a typical program the context
-// function will be called many times without ever recording a
-// traceback for that context. Recording a complete stack trace in a
-// call to the context function is likely to be inefficient.
-//
-// The traceback function will be called with a single argument, a
-// pointer to a struct:
-//
-//	struct {
-//		Context    uintptr
-//		SigContext uintptr
-//		Buf        *uintptr
-//		Max        uintptr
-//	}
-//
-// In C syntax, this struct will be
-//
-//	struct {
-//		uintptr_t  Context;
-//		uintptr_t  SigContext;
-//		uintptr_t* Buf;
-//		uintptr_t  Max;
-//	};
-//
-// The Context field will be zero to gather a traceback from the
-// current program execution point. In this case, the traceback
-// function will be called from C code.
-//
-// Otherwise Context will be a value previously returned by a call to
-// the context function. The traceback function should gather a stack
-// trace from that saved point in the program execution. The traceback
-// function may be called from an execution thread other than the one
-// that recorded the context, but only when the context is known to be
-// valid and unchanging. The traceback function may also be called
-// deeper in the call stack on the same thread that recorded the
-// context. The traceback function may be called multiple times with
-// the same Context value; it will usually be appropriate to cache the
-// result, if possible, the first time this is called for a specific
-// context value.
-//
-// If the traceback function is called from a signal handler on a Unix
-// system, SigContext will be the signal context argument passed to
-// the signal handler (a C ucontext_t* cast to uintptr_t). This may be
-// used to start tracing at the point where the signal occurred. If
-// the traceback function is not called from a signal handler,
-// SigContext will be zero.
-//
-// Buf is where the traceback information should be stored. It should
-// be PC values, such that Buf[0] is the PC of the caller, Buf[1] is
-// the PC of that function's caller, and so on.  Max is the maximum
-// number of entries to store.  The function should store a zero to
-// indicate the top of the stack, or that the caller is on a different
-// stack, presumably a Go stack.
-//
-// Unlike runtime.Callers, the PC values returned should, when passed
-// to the symbolizer function, return the file/line of the call
-// instruction.  No additional subtraction is required or appropriate.
-//
-// On all platforms, the traceback function is invoked when a call from
-// Go to C to Go requests a stack trace. On linux/amd64, linux/ppc64le,
-// and freebsd/amd64, the traceback function is also invoked when a
-// signal is received by a thread that is executing a cgo call. The
-// traceback function should not make assumptions about when it is
-// called, as future versions of Go may make additional calls.
-//
-// The symbolizer function will be called with a single argument, a
-// pointer to a struct:
-//
-//	struct {
-//		PC      uintptr // program counter to fetch information for
-//		File    *byte   // file name (NUL terminated)
-//		Lineno  uintptr // line number
-//		Func    *byte   // function name (NUL terminated)
-//		Entry   uintptr // function entry point
-//		More    uintptr // set non-zero if more info for this PC
-//		Data    uintptr // unused by runtime, available for function
-//	}
-//
-// In C syntax, this struct will be
-//
-//	struct {
-//		uintptr_t PC;
-//		char*     File;
-//		uintptr_t Lineno;
-//		char*     Func;
-//		uintptr_t Entry;
-//		uintptr_t More;
-//		uintptr_t Data;
-//	};
-//
-// The PC field will be a value returned by a call to the traceback
-// function.
-//
-// The first time the function is called for a particular traceback,
-// all the fields except PC will be 0. The function should fill in the
-// other fields if possible, setting them to 0/nil if the information
-// is not available. The Data field may be used to store any useful
-// information across calls. The More field should be set to non-zero
-// if there is more information for this PC, zero otherwise. If More
-// is set non-zero, the function will be called again with the same
-// PC, and may return different information (this is intended for use
-// with inlined functions). If More is zero, the function will be
-// called with the next PC value in the traceback. When the traceback
-// is complete, the function will be called once more with PC set to
-// zero; this may be used to free any information. Each call will
-// leave the fields of the struct set to the same values they had upon
-// return, except for the PC field when the More field is zero. The
-// function must not keep a copy of the struct pointer between calls.
-//
-// When calling SetCgoTraceback, the version argument is the version
-// number of the structs that the functions expect to receive.
-// Currently this must be zero.
-//
-// The symbolizer function may be nil, in which case the results of
-// the traceback function will be displayed as numbers. If the
-// traceback function is nil, the symbolizer function will never be
-// called. The context function may be nil, in which case the
-// traceback function will only be called with the context field set
-// to zero.  If the context function is nil, then calls from Go to C
-// to Go will not show a traceback for the C portion of the call stack.
-//
-// SetCgoTraceback should be called only once, ideally from an init function.
-func SetCgoTraceback(version int, traceback, context, symbolizer unsafe.Pointer) {
-	if version != 0 {
-		panic("unsupported version")
-	}
-
-	if cgoTraceback != nil && cgoTraceback != traceback ||
-		cgoContext != nil && cgoContext != context ||
-		cgoSymbolizer != nil && cgoSymbolizer != symbolizer {
-		panic("call SetCgoTraceback only once")
-	}
-
-	cgoTraceback = traceback
-	cgoContext = context
-	cgoSymbolizer = symbolizer
-
-	// The context function is called when a C function calls a Go
-	// function. As such it is only called by C code in runtime/cgo.
-	if _cgo_set_context_function != nil {
-		cgocall(_cgo_set_context_function, context)
-	}
-}
-
-var cgoTraceback unsafe.Pointer
-var cgoContext unsafe.Pointer
-var cgoSymbolizer unsafe.Pointer
-
-// cgoTracebackArg is the type passed to cgoTraceback.
-type cgoTracebackArg struct {
-	context    uintptr
-	sigContext uintptr
-	buf        *uintptr
-	max        uintptr
-}
-
-// cgoContextArg is the type passed to the context function.
-type cgoContextArg struct {
-	context uintptr
-}
-
-// cgoSymbolizerArg is the type passed to cgoSymbolizer.
-type cgoSymbolizerArg struct {
-	pc       uintptr
-	file     *byte
-	lineno   uintptr
-	funcName *byte
-	entry    uintptr
-	more     uintptr
-	data     uintptr
-}
-
-// cgoTraceback prints a traceback of callers.
-func printCgoTraceback(callers *cgoCallers) {
-	if cgoSymbolizer == nil {
-		for _, c := range callers {
-			if c == 0 {
-				break
-			}
-			print("non-Go function at pc=", hex(c), "\n")
-		}
-		return
-	}
-
-	var arg cgoSymbolizerArg
-	for _, c := range callers {
-		if c == 0 {
-			break
-		}
-		printOneCgoTraceback(c, 0x7fffffff, &arg)
-	}
-	arg.pc = 0
-	callCgoSymbolizer(&arg)
-}
-
-// printOneCgoTraceback prints the traceback of a single cgo caller.
-// This can print more than one line because of inlining.
-// Returns the number of frames printed.
-func printOneCgoTraceback(pc uintptr, max int, arg *cgoSymbolizerArg) int {
-	c := 0
-	arg.pc = pc
-	for c <= max {
-		callCgoSymbolizer(arg)
-		if arg.funcName != nil {
-			// Note that we don't print any argument
-			// information here, not even parentheses.
-			// The symbolizer must add that if appropriate.
-			println(gostringnocopy(arg.funcName))
-		} else {
-			println("non-Go function")
-		}
-		print("\t")
-		if arg.file != nil {
-			print(gostringnocopy(arg.file), ":", arg.lineno, " ")
-		}
-		print("pc=", hex(pc), "\n")
-		c++
-		if arg.more == 0 {
-			break
-		}
-	}
-	return c
-}
-
-// callCgoSymbolizer calls the cgoSymbolizer function.
-func callCgoSymbolizer(arg *cgoSymbolizerArg) {
-	call := cgocall
-	if panicking > 0 || getg().m.curg != getg() {
-		// We do not want to call into the scheduler when panicking
-		// or when on the system stack.
-		call = asmcgocall
-	}
-	if msanenabled {
-		msanwrite(unsafe.Pointer(arg), unsafe.Sizeof(cgoSymbolizerArg{}))
-	}
-	if asanenabled {
-		asanwrite(unsafe.Pointer(arg), unsafe.Sizeof(cgoSymbolizerArg{}))
-	}
-	call(cgoSymbolizer, noescape(unsafe.Pointer(arg)))
-}
-
-// cgoContextPCs gets the PC values from a cgo traceback.
-func cgoContextPCs(ctxt uintptr, buf []uintptr) {
-	if cgoTraceback == nil {
-		return
-	}
-	call := cgocall
-	if panicking > 0 || getg().m.curg != getg() {
-		// We do not want to call into the scheduler when panicking
-		// or when on the system stack.
-		call = asmcgocall
-	}
-	arg := cgoTracebackArg{
-		context: ctxt,
-		buf:     (*uintptr)(noescape(unsafe.Pointer(&buf[0]))),
-		max:     uintptr(len(buf)),
-	}
-	if msanenabled {
-		msanwrite(unsafe.Pointer(&arg), unsafe.Sizeof(arg))
-	}
-	if asanenabled {
-		asanwrite(unsafe.Pointer(&arg), unsafe.Sizeof(arg))
-	}
-	call(cgoTraceback, noescape(unsafe.Pointer(&arg)))
-}
diff --git a/contrib/go/_std_1.18/src/runtime/type.go b/contrib/go/_std_1.18/src/runtime/type.go
deleted file mode 100644
index da47147897..0000000000
--- a/contrib/go/_std_1.18/src/runtime/type.go
+++ /dev/null
@@ -1,708 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Runtime type representation.
-
-package runtime
-
-import (
-	"internal/abi"
-	"unsafe"
-)
-
-// tflag is documented in reflect/type.go.
-//
-// tflag values must be kept in sync with copies in:
-//	cmd/compile/internal/reflectdata/reflect.go
-//	cmd/link/internal/ld/decodesym.go
-//	reflect/type.go
-//      internal/reflectlite/type.go
-type tflag uint8
-
-const (
-	tflagUncommon      tflag = 1 << 0
-	tflagExtraStar     tflag = 1 << 1
-	tflagNamed         tflag = 1 << 2
-	tflagRegularMemory tflag = 1 << 3 // equal and hash can treat values of this type as a single region of t.size bytes
-)
-
-// Needs to be in sync with ../cmd/link/internal/ld/decodesym.go:/^func.commonsize,
-// ../cmd/compile/internal/reflectdata/reflect.go:/^func.dcommontype and
-// ../reflect/type.go:/^type.rtype.
-// ../internal/reflectlite/type.go:/^type.rtype.
-type _type struct {
-	size       uintptr
-	ptrdata    uintptr // size of memory prefix holding all pointers
-	hash       uint32
-	tflag      tflag
-	align      uint8
-	fieldAlign uint8
-	kind       uint8
-	// function for comparing objects of this type
-	// (ptr to object A, ptr to object B) -> ==?
-	equal func(unsafe.Pointer, unsafe.Pointer) bool
-	// gcdata stores the GC type data for the garbage collector.
-	// If the KindGCProg bit is set in kind, gcdata is a GC program.
-	// Otherwise it is a ptrmask bitmap. See mbitmap.go for details.
-	gcdata    *byte
-	str       nameOff
-	ptrToThis typeOff
-}
-
-func (t *_type) string() string {
-	s := t.nameOff(t.str).name()
-	if t.tflag&tflagExtraStar != 0 {
-		return s[1:]
-	}
-	return s
-}
-
-func (t *_type) uncommon() *uncommontype {
-	if t.tflag&tflagUncommon == 0 {
-		return nil
-	}
-	switch t.kind & kindMask {
-	case kindStruct:
-		type u struct {
-			structtype
-			u uncommontype
-		}
-		return &(*u)(unsafe.Pointer(t)).u
-	case kindPtr:
-		type u struct {
-			ptrtype
-			u uncommontype
-		}
-		return &(*u)(unsafe.Pointer(t)).u
-	case kindFunc:
-		type u struct {
-			functype
-			u uncommontype
-		}
-		return &(*u)(unsafe.Pointer(t)).u
-	case kindSlice:
-		type u struct {
-			slicetype
-			u uncommontype
-		}
-		return &(*u)(unsafe.Pointer(t)).u
-	case kindArray:
-		type u struct {
-			arraytype
-			u uncommontype
-		}
-		return &(*u)(unsafe.Pointer(t)).u
-	case kindChan:
-		type u struct {
-			chantype
-			u uncommontype
-		}
-		return &(*u)(unsafe.Pointer(t)).u
-	case kindMap:
-		type u struct {
-			maptype
-			u uncommontype
-		}
-		return &(*u)(unsafe.Pointer(t)).u
-	case kindInterface:
-		type u struct {
-			interfacetype
-			u uncommontype
-		}
-		return &(*u)(unsafe.Pointer(t)).u
-	default:
-		type u struct {
-			_type
-			u uncommontype
-		}
-		return &(*u)(unsafe.Pointer(t)).u
-	}
-}
-
-func (t *_type) name() string {
-	if t.tflag&tflagNamed == 0 {
-		return ""
-	}
-	s := t.string()
-	i := len(s) - 1
-	for i >= 0 && s[i] != '.' {
-		i--
-	}
-	return s[i+1:]
-}
-
-// pkgpath returns the path of the package where t was defined, if
-// available. This is not the same as the reflect package's PkgPath
-// method, in that it returns the package path for struct and interface
-// types, not just named types.
-func (t *_type) pkgpath() string {
-	if u := t.uncommon(); u != nil {
-		return t.nameOff(u.pkgpath).name()
-	}
-	switch t.kind & kindMask {
-	case kindStruct:
-		st := (*structtype)(unsafe.Pointer(t))
-		return st.pkgPath.name()
-	case kindInterface:
-		it := (*interfacetype)(unsafe.Pointer(t))
-		return it.pkgpath.name()
-	}
-	return ""
-}
-
-// reflectOffs holds type offsets defined at run time by the reflect package.
-//
-// When a type is defined at run time, its *rtype data lives on the heap.
-// There are a wide range of possible addresses the heap may use, that
-// may not be representable as a 32-bit offset. Moreover the GC may
-// one day start moving heap memory, in which case there is no stable
-// offset that can be defined.
-//
-// To provide stable offsets, we add pin *rtype objects in a global map
-// and treat the offset as an identifier. We use negative offsets that
-// do not overlap with any compile-time module offsets.
-//
-// Entries are created by reflect.addReflectOff.
-var reflectOffs struct {
-	lock mutex
-	next int32
-	m    map[int32]unsafe.Pointer
-	minv map[unsafe.Pointer]int32
-}
-
-func reflectOffsLock() {
-	lock(&reflectOffs.lock)
-	if raceenabled {
-		raceacquire(unsafe.Pointer(&reflectOffs.lock))
-	}
-}
-
-func reflectOffsUnlock() {
-	if raceenabled {
-		racerelease(unsafe.Pointer(&reflectOffs.lock))
-	}
-	unlock(&reflectOffs.lock)
-}
-
-func resolveNameOff(ptrInModule unsafe.Pointer, off nameOff) name {
-	if off == 0 {
-		return name{}
-	}
-	base := uintptr(ptrInModule)
-	for md := &firstmoduledata; md != nil; md = md.next {
-		if base >= md.types && base < md.etypes {
-			res := md.types + uintptr(off)
-			if res > md.etypes {
-				println("runtime: nameOff", hex(off), "out of range", hex(md.types), "-", hex(md.etypes))
-				throw("runtime: name offset out of range")
-			}
-			return name{(*byte)(unsafe.Pointer(res))}
-		}
-	}
-
-	// No module found. see if it is a run time name.
-	reflectOffsLock()
-	res, found := reflectOffs.m[int32(off)]
-	reflectOffsUnlock()
-	if !found {
-		println("runtime: nameOff", hex(off), "base", hex(base), "not in ranges:")
-		for next := &firstmoduledata; next != nil; next = next.next {
-			println("\ttypes", hex(next.types), "etypes", hex(next.etypes))
-		}
-		throw("runtime: name offset base pointer out of range")
-	}
-	return name{(*byte)(res)}
-}
-
-func (t *_type) nameOff(off nameOff) name {
-	return resolveNameOff(unsafe.Pointer(t), off)
-}
-
-func resolveTypeOff(ptrInModule unsafe.Pointer, off typeOff) *_type {
-	if off == 0 || off == -1 {
-		// -1 is the sentinel value for unreachable code.
-		// See cmd/link/internal/ld/data.go:relocsym.
-		return nil
-	}
-	base := uintptr(ptrInModule)
-	var md *moduledata
-	for next := &firstmoduledata; next != nil; next = next.next {
-		if base >= next.types && base < next.etypes {
-			md = next
-			break
-		}
-	}
-	if md == nil {
-		reflectOffsLock()
-		res := reflectOffs.m[int32(off)]
-		reflectOffsUnlock()
-		if res == nil {
-			println("runtime: typeOff", hex(off), "base", hex(base), "not in ranges:")
-			for next := &firstmoduledata; next != nil; next = next.next {
-				println("\ttypes", hex(next.types), "etypes", hex(next.etypes))
-			}
-			throw("runtime: type offset base pointer out of range")
-		}
-		return (*_type)(res)
-	}
-	if t := md.typemap[off]; t != nil {
-		return t
-	}
-	res := md.types + uintptr(off)
-	if res > md.etypes {
-		println("runtime: typeOff", hex(off), "out of range", hex(md.types), "-", hex(md.etypes))
-		throw("runtime: type offset out of range")
-	}
-	return (*_type)(unsafe.Pointer(res))
-}
-
-func (t *_type) typeOff(off typeOff) *_type {
-	return resolveTypeOff(unsafe.Pointer(t), off)
-}
-
-func (t *_type) textOff(off textOff) unsafe.Pointer {
-	if off == -1 {
-		// -1 is the sentinel value for unreachable code.
-		// See cmd/link/internal/ld/data.go:relocsym.
-		return unsafe.Pointer(abi.FuncPCABIInternal(unreachableMethod))
-	}
-	base := uintptr(unsafe.Pointer(t))
-	var md *moduledata
-	for next := &firstmoduledata; next != nil; next = next.next {
-		if base >= next.types && base < next.etypes {
-			md = next
-			break
-		}
-	}
-	if md == nil {
-		reflectOffsLock()
-		res := reflectOffs.m[int32(off)]
-		reflectOffsUnlock()
-		if res == nil {
-			println("runtime: textOff", hex(off), "base", hex(base), "not in ranges:")
-			for next := &firstmoduledata; next != nil; next = next.next {
-				println("\ttypes", hex(next.types), "etypes", hex(next.etypes))
-			}
-			throw("runtime: text offset base pointer out of range")
-		}
-		return res
-	}
-	res := md.textAddr(uint32(off))
-	return unsafe.Pointer(res)
-}
-
-func (t *functype) in() []*_type {
-	// See funcType in reflect/type.go for details on data layout.
-	uadd := uintptr(unsafe.Sizeof(functype{}))
-	if t.typ.tflag&tflagUncommon != 0 {
-		uadd += unsafe.Sizeof(uncommontype{})
-	}
-	return (*[1 << 20]*_type)(add(unsafe.Pointer(t), uadd))[:t.inCount]
-}
-
-func (t *functype) out() []*_type {
-	// See funcType in reflect/type.go for details on data layout.
-	uadd := uintptr(unsafe.Sizeof(functype{}))
-	if t.typ.tflag&tflagUncommon != 0 {
-		uadd += unsafe.Sizeof(uncommontype{})
-	}
-	outCount := t.outCount & (1<<15 - 1)
-	return (*[1 << 20]*_type)(add(unsafe.Pointer(t), uadd))[t.inCount : t.inCount+outCount]
-}
-
-func (t *functype) dotdotdot() bool {
-	return t.outCount&(1<<15) != 0
-}
-
-type nameOff int32
-type typeOff int32
-type textOff int32
-
-type method struct {
-	name nameOff
-	mtyp typeOff
-	ifn  textOff
-	tfn  textOff
-}
-
-type uncommontype struct {
-	pkgpath nameOff
-	mcount  uint16 // number of methods
-	xcount  uint16 // number of exported methods
-	moff    uint32 // offset from this uncommontype to [mcount]method
-	_       uint32 // unused
-}
-
-type imethod struct {
-	name nameOff
-	ityp typeOff
-}
-
-type interfacetype struct {
-	typ     _type
-	pkgpath name
-	mhdr    []imethod
-}
-
-type maptype struct {
-	typ    _type
-	key    *_type
-	elem   *_type
-	bucket *_type // internal type representing a hash bucket
-	// function for hashing keys (ptr to key, seed) -> hash
-	hasher     func(unsafe.Pointer, uintptr) uintptr
-	keysize    uint8  // size of key slot
-	elemsize   uint8  // size of elem slot
-	bucketsize uint16 // size of bucket
-	flags      uint32
-}
-
-// Note: flag values must match those used in the TMAP case
-// in ../cmd/compile/internal/reflectdata/reflect.go:writeType.
-func (mt *maptype) indirectkey() bool { // store ptr to key instead of key itself
-	return mt.flags&1 != 0
-}
-func (mt *maptype) indirectelem() bool { // store ptr to elem instead of elem itself
-	return mt.flags&2 != 0
-}
-func (mt *maptype) reflexivekey() bool { // true if k==k for all keys
-	return mt.flags&4 != 0
-}
-func (mt *maptype) needkeyupdate() bool { // true if we need to update key on an overwrite
-	return mt.flags&8 != 0
-}
-func (mt *maptype) hashMightPanic() bool { // true if hash function might panic
-	return mt.flags&16 != 0
-}
-
-type arraytype struct {
-	typ   _type
-	elem  *_type
-	slice *_type
-	len   uintptr
-}
-
-type chantype struct {
-	typ  _type
-	elem *_type
-	dir  uintptr
-}
-
-type slicetype struct {
-	typ  _type
-	elem *_type
-}
-
-type functype struct {
-	typ      _type
-	inCount  uint16
-	outCount uint16
-}
-
-type ptrtype struct {
-	typ  _type
-	elem *_type
-}
-
-type structfield struct {
-	name       name
-	typ        *_type
-	offsetAnon uintptr
-}
-
-func (f *structfield) offset() uintptr {
-	return f.offsetAnon >> 1
-}
-
-type structtype struct {
-	typ     _type
-	pkgPath name
-	fields  []structfield
-}
-
-// name is an encoded type name with optional extra data.
-// See reflect/type.go for details.
-type name struct {
-	bytes *byte
-}
-
-func (n name) data(off int) *byte {
-	return (*byte)(add(unsafe.Pointer(n.bytes), uintptr(off)))
-}
-
-func (n name) isExported() bool {
-	return (*n.bytes)&(1<<0) != 0
-}
-
-func (n name) readvarint(off int) (int, int) {
-	v := 0
-	for i := 0; ; i++ {
-		x := *n.data(off + i)
-		v += int(x&0x7f) << (7 * i)
-		if x&0x80 == 0 {
-			return i + 1, v
-		}
-	}
-}
-
-func (n name) name() (s string) {
-	if n.bytes == nil {
-		return ""
-	}
-	i, l := n.readvarint(1)
-	if l == 0 {
-		return ""
-	}
-	hdr := (*stringStruct)(unsafe.Pointer(&s))
-	hdr.str = unsafe.Pointer(n.data(1 + i))
-	hdr.len = l
-	return
-}
-
-func (n name) tag() (s string) {
-	if *n.data(0)&(1<<1) == 0 {
-		return ""
-	}
-	i, l := n.readvarint(1)
-	i2, l2 := n.readvarint(1 + i + l)
-	hdr := (*stringStruct)(unsafe.Pointer(&s))
-	hdr.str = unsafe.Pointer(n.data(1 + i + l + i2))
-	hdr.len = l2
-	return
-}
-
-func (n name) pkgPath() string {
-	if n.bytes == nil || *n.data(0)&(1<<2) == 0 {
-		return ""
-	}
-	i, l := n.readvarint(1)
-	off := 1 + i + l
-	if *n.data(0)&(1<<1) != 0 {
-		i2, l2 := n.readvarint(off)
-		off += i2 + l2
-	}
-	var nameOff nameOff
-	copy((*[4]byte)(unsafe.Pointer(&nameOff))[:], (*[4]byte)(unsafe.Pointer(n.data(off)))[:])
-	pkgPathName := resolveNameOff(unsafe.Pointer(n.bytes), nameOff)
-	return pkgPathName.name()
-}
-
-func (n name) isBlank() bool {
-	if n.bytes == nil {
-		return false
-	}
-	_, l := n.readvarint(1)
-	return l == 1 && *n.data(2) == '_'
-}
-
-// typelinksinit scans the types from extra modules and builds the
-// moduledata typemap used to de-duplicate type pointers.
-func typelinksinit() {
-	if firstmoduledata.next == nil {
-		return
-	}
-	typehash := make(map[uint32][]*_type, len(firstmoduledata.typelinks))
-
-	modules := activeModules()
-	prev := modules[0]
-	for _, md := range modules[1:] {
-		// Collect types from the previous module into typehash.
-	collect:
-		for _, tl := range prev.typelinks {
-			var t *_type
-			if prev.typemap == nil {
-				t = (*_type)(unsafe.Pointer(prev.types + uintptr(tl)))
-			} else {
-				t = prev.typemap[typeOff(tl)]
-			}
-			// Add to typehash if not seen before.
-			tlist := typehash[t.hash]
-			for _, tcur := range tlist {
-				if tcur == t {
-					continue collect
-				}
-			}
-			typehash[t.hash] = append(tlist, t)
-		}
-
-		if md.typemap == nil {
-			// If any of this module's typelinks match a type from a
-			// prior module, prefer that prior type by adding the offset
-			// to this module's typemap.
-			tm := make(map[typeOff]*_type, len(md.typelinks))
-			pinnedTypemaps = append(pinnedTypemaps, tm)
-			md.typemap = tm
-			for _, tl := range md.typelinks {
-				t := (*_type)(unsafe.Pointer(md.types + uintptr(tl)))
-				for _, candidate := range typehash[t.hash] {
-					seen := map[_typePair]struct{}{}
-					if typesEqual(t, candidate, seen) {
-						t = candidate
-						break
-					}
-				}
-				md.typemap[typeOff(tl)] = t
-			}
-		}
-
-		prev = md
-	}
-}
-
-type _typePair struct {
-	t1 *_type
-	t2 *_type
-}
-
-// typesEqual reports whether two types are equal.
-//
-// Everywhere in the runtime and reflect packages, it is assumed that
-// there is exactly one *_type per Go type, so that pointer equality
-// can be used to test if types are equal. There is one place that
-// breaks this assumption: buildmode=shared. In this case a type can
-// appear as two different pieces of memory. This is hidden from the
-// runtime and reflect package by the per-module typemap built in
-// typelinksinit. It uses typesEqual to map types from later modules
-// back into earlier ones.
-//
-// Only typelinksinit needs this function.
-func typesEqual(t, v *_type, seen map[_typePair]struct{}) bool {
-	tp := _typePair{t, v}
-	if _, ok := seen[tp]; ok {
-		return true
-	}
-
-	// mark these types as seen, and thus equivalent which prevents an infinite loop if
-	// the two types are identical, but recursively defined and loaded from
-	// different modules
-	seen[tp] = struct{}{}
-
-	if t == v {
-		return true
-	}
-	kind := t.kind & kindMask
-	if kind != v.kind&kindMask {
-		return false
-	}
-	if t.string() != v.string() {
-		return false
-	}
-	ut := t.uncommon()
-	uv := v.uncommon()
-	if ut != nil || uv != nil {
-		if ut == nil || uv == nil {
-			return false
-		}
-		pkgpatht := t.nameOff(ut.pkgpath).name()
-		pkgpathv := v.nameOff(uv.pkgpath).name()
-		if pkgpatht != pkgpathv {
-			return false
-		}
-	}
-	if kindBool <= kind && kind <= kindComplex128 {
-		return true
-	}
-	switch kind {
-	case kindString, kindUnsafePointer:
-		return true
-	case kindArray:
-		at := (*arraytype)(unsafe.Pointer(t))
-		av := (*arraytype)(unsafe.Pointer(v))
-		return typesEqual(at.elem, av.elem, seen) && at.len == av.len
-	case kindChan:
-		ct := (*chantype)(unsafe.Pointer(t))
-		cv := (*chantype)(unsafe.Pointer(v))
-		return ct.dir == cv.dir && typesEqual(ct.elem, cv.elem, seen)
-	case kindFunc:
-		ft := (*functype)(unsafe.Pointer(t))
-		fv := (*functype)(unsafe.Pointer(v))
-		if ft.outCount != fv.outCount || ft.inCount != fv.inCount {
-			return false
-		}
-		tin, vin := ft.in(), fv.in()
-		for i := 0; i < len(tin); i++ {
-			if !typesEqual(tin[i], vin[i], seen) {
-				return false
-			}
-		}
-		tout, vout := ft.out(), fv.out()
-		for i := 0; i < len(tout); i++ {
-			if !typesEqual(tout[i], vout[i], seen) {
-				return false
-			}
-		}
-		return true
-	case kindInterface:
-		it := (*interfacetype)(unsafe.Pointer(t))
-		iv := (*interfacetype)(unsafe.Pointer(v))
-		if it.pkgpath.name() != iv.pkgpath.name() {
-			return false
-		}
-		if len(it.mhdr) != len(iv.mhdr) {
-			return false
-		}
-		for i := range it.mhdr {
-			tm := &it.mhdr[i]
-			vm := &iv.mhdr[i]
-			// Note the mhdr array can be relocated from
-			// another module. See #17724.
-			tname := resolveNameOff(unsafe.Pointer(tm), tm.name)
-			vname := resolveNameOff(unsafe.Pointer(vm), vm.name)
-			if tname.name() != vname.name() {
-				return false
-			}
-			if tname.pkgPath() != vname.pkgPath() {
-				return false
-			}
-			tityp := resolveTypeOff(unsafe.Pointer(tm), tm.ityp)
-			vityp := resolveTypeOff(unsafe.Pointer(vm), vm.ityp)
-			if !typesEqual(tityp, vityp, seen) {
-				return false
-			}
-		}
-		return true
-	case kindMap:
-		mt := (*maptype)(unsafe.Pointer(t))
-		mv := (*maptype)(unsafe.Pointer(v))
-		return typesEqual(mt.key, mv.key, seen) && typesEqual(mt.elem, mv.elem, seen)
-	case kindPtr:
-		pt := (*ptrtype)(unsafe.Pointer(t))
-		pv := (*ptrtype)(unsafe.Pointer(v))
-		return typesEqual(pt.elem, pv.elem, seen)
-	case kindSlice:
-		st := (*slicetype)(unsafe.Pointer(t))
-		sv := (*slicetype)(unsafe.Pointer(v))
-		return typesEqual(st.elem, sv.elem, seen)
-	case kindStruct:
-		st := (*structtype)(unsafe.Pointer(t))
-		sv := (*structtype)(unsafe.Pointer(v))
-		if len(st.fields) != len(sv.fields) {
-			return false
-		}
-		if st.pkgPath.name() != sv.pkgPath.name() {
-			return false
-		}
-		for i := range st.fields {
-			tf := &st.fields[i]
-			vf := &sv.fields[i]
-			if tf.name.name() != vf.name.name() {
-				return false
-			}
-			if !typesEqual(tf.typ, vf.typ, seen) {
-				return false
-			}
-			if tf.name.tag() != vf.name.tag() {
-				return false
-			}
-			if tf.offsetAnon != vf.offsetAnon {
-				return false
-			}
-		}
-		return true
-	default:
-		println("runtime: impossible type kind", kind)
-		throw("runtime: impossible type kind")
-		return false
-	}
-}
diff --git a/contrib/go/_std_1.18/src/runtime/vdso_elf64.go b/contrib/go/_std_1.18/src/runtime/vdso_elf64.go
deleted file mode 100644
index d46d6f8c34..0000000000
--- a/contrib/go/_std_1.18/src/runtime/vdso_elf64.go
+++ /dev/null
@@ -1,79 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build linux && (amd64 || arm64 || mips64 || mips64le || ppc64 || ppc64le || riscv64)
-
-package runtime
-
-// ELF64 structure definitions for use by the vDSO loader
-
-type elfSym struct {
-	st_name  uint32
-	st_info  byte
-	st_other byte
-	st_shndx uint16
-	st_value uint64
-	st_size  uint64
-}
-
-type elfVerdef struct {
-	vd_version uint16 /* Version revision */
-	vd_flags   uint16 /* Version information */
-	vd_ndx     uint16 /* Version Index */
-	vd_cnt     uint16 /* Number of associated aux entries */
-	vd_hash    uint32 /* Version name hash value */
-	vd_aux     uint32 /* Offset in bytes to verdaux array */
-	vd_next    uint32 /* Offset in bytes to next verdef entry */
-}
-
-type elfEhdr struct {
-	e_ident     [_EI_NIDENT]byte /* Magic number and other info */
-	e_type      uint16           /* Object file type */
-	e_machine   uint16           /* Architecture */
-	e_version   uint32           /* Object file version */
-	e_entry     uint64           /* Entry point virtual address */
-	e_phoff     uint64           /* Program header table file offset */
-	e_shoff     uint64           /* Section header table file offset */
-	e_flags     uint32           /* Processor-specific flags */
-	e_ehsize    uint16           /* ELF header size in bytes */
-	e_phentsize uint16           /* Program header table entry size */
-	e_phnum     uint16           /* Program header table entry count */
-	e_shentsize uint16           /* Section header table entry size */
-	e_shnum     uint16           /* Section header table entry count */
-	e_shstrndx  uint16           /* Section header string table index */
-}
-
-type elfPhdr struct {
-	p_type   uint32 /* Segment type */
-	p_flags  uint32 /* Segment flags */
-	p_offset uint64 /* Segment file offset */
-	p_vaddr  uint64 /* Segment virtual address */
-	p_paddr  uint64 /* Segment physical address */
-	p_filesz uint64 /* Segment size in file */
-	p_memsz  uint64 /* Segment size in memory */
-	p_align  uint64 /* Segment alignment */
-}
-
-type elfShdr struct {
-	sh_name      uint32 /* Section name (string tbl index) */
-	sh_type      uint32 /* Section type */
-	sh_flags     uint64 /* Section flags */
-	sh_addr      uint64 /* Section virtual addr at execution */
-	sh_offset    uint64 /* Section file offset */
-	sh_size      uint64 /* Section size in bytes */
-	sh_link      uint32 /* Link to another section */
-	sh_info      uint32 /* Additional section information */
-	sh_addralign uint64 /* Section alignment */
-	sh_entsize   uint64 /* Entry size if section holds table */
-}
-
-type elfDyn struct {
-	d_tag int64  /* Dynamic entry type */
-	d_val uint64 /* Integer value */
-}
-
-type elfVerdaux struct {
-	vda_name uint32 /* Version or dependency names */
-	vda_next uint32 /* Offset in bytes to next verdaux entry */
-}
diff --git a/contrib/go/_std_1.18/src/runtime/vdso_in_none.go b/contrib/go/_std_1.18/src/runtime/vdso_in_none.go
deleted file mode 100644
index 618bd39b42..0000000000
--- a/contrib/go/_std_1.18/src/runtime/vdso_in_none.go
+++ /dev/null
@@ -1,13 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build (linux && !386 && !amd64 && !arm && !arm64 && !mips64 && !mips64le && !ppc64 && !ppc64le && !riscv64) || !linux
-
-package runtime
-
-// A dummy version of inVDSOPage for targets that don't use a VDSO.
-
-func inVDSOPage(pc uintptr) bool {
-	return false
-}
diff --git a/contrib/go/_std_1.18/src/runtime/vdso_linux.go b/contrib/go/_std_1.18/src/runtime/vdso_linux.go
deleted file mode 100644
index cff2000767..0000000000
--- a/contrib/go/_std_1.18/src/runtime/vdso_linux.go
+++ /dev/null
@@ -1,292 +0,0 @@
-// Copyright 2012 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build linux && (386 || amd64 || arm || arm64 || mips64 || mips64le || ppc64 || ppc64le || riscv64)
-
-package runtime
-
-import "unsafe"
-
-// Look up symbols in the Linux vDSO.
-
-// This code was originally based on the sample Linux vDSO parser at
-// https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/tools/testing/selftests/vDSO/parse_vdso.c
-
-// This implements the ELF dynamic linking spec at
-// http://sco.com/developers/gabi/latest/ch5.dynamic.html
-
-// The version section is documented at
-// https://refspecs.linuxfoundation.org/LSB_3.2.0/LSB-Core-generic/LSB-Core-generic/symversion.html
-
-const (
-	_AT_SYSINFO_EHDR = 33
-
-	_PT_LOAD    = 1 /* Loadable program segment */
-	_PT_DYNAMIC = 2 /* Dynamic linking information */
-
-	_DT_NULL     = 0          /* Marks end of dynamic section */
-	_DT_HASH     = 4          /* Dynamic symbol hash table */
-	_DT_STRTAB   = 5          /* Address of string table */
-	_DT_SYMTAB   = 6          /* Address of symbol table */
-	_DT_GNU_HASH = 0x6ffffef5 /* GNU-style dynamic symbol hash table */
-	_DT_VERSYM   = 0x6ffffff0
-	_DT_VERDEF   = 0x6ffffffc
-
-	_VER_FLG_BASE = 0x1 /* Version definition of file itself */
-
-	_SHN_UNDEF = 0 /* Undefined section */
-
-	_SHT_DYNSYM = 11 /* Dynamic linker symbol table */
-
-	_STT_FUNC = 2 /* Symbol is a code object */
-
-	_STT_NOTYPE = 0 /* Symbol type is not specified */
-
-	_STB_GLOBAL = 1 /* Global symbol */
-	_STB_WEAK   = 2 /* Weak symbol */
-
-	_EI_NIDENT = 16
-
-	// Maximum indices for the array types used when traversing the vDSO ELF structures.
-	// Computed from architecture-specific max provided by vdso_linux_*.go
-	vdsoSymTabSize     = vdsoArrayMax / unsafe.Sizeof(elfSym{})
-	vdsoDynSize        = vdsoArrayMax / unsafe.Sizeof(elfDyn{})
-	vdsoSymStringsSize = vdsoArrayMax     // byte
-	vdsoVerSymSize     = vdsoArrayMax / 2 // uint16
-	vdsoHashSize       = vdsoArrayMax / 4 // uint32
-
-	// vdsoBloomSizeScale is a scaling factor for gnuhash tables which are uint32 indexed,
-	// but contain uintptrs
-	vdsoBloomSizeScale = unsafe.Sizeof(uintptr(0)) / 4 // uint32
-)
-
-/* How to extract and insert information held in the st_info field.  */
-func _ELF_ST_BIND(val byte) byte { return val >> 4 }
-func _ELF_ST_TYPE(val byte) byte { return val & 0xf }
-
-type vdsoSymbolKey struct {
-	name    string
-	symHash uint32
-	gnuHash uint32
-	ptr     *uintptr
-}
-
-type vdsoVersionKey struct {
-	version string
-	verHash uint32
-}
-
-type vdsoInfo struct {
-	valid bool
-
-	/* Load information */
-	loadAddr   uintptr
-	loadOffset uintptr /* loadAddr - recorded vaddr */
-
-	/* Symbol table */
-	symtab     *[vdsoSymTabSize]elfSym
-	symstrings *[vdsoSymStringsSize]byte
-	chain      []uint32
-	bucket     []uint32
-	symOff     uint32
-	isGNUHash  bool
-
-	/* Version table */
-	versym *[vdsoVerSymSize]uint16
-	verdef *elfVerdef
-}
-
-// see vdso_linux_*.go for vdsoSymbolKeys[] and vdso*Sym vars
-
-func vdsoInitFromSysinfoEhdr(info *vdsoInfo, hdr *elfEhdr) {
-	info.valid = false
-	info.loadAddr = uintptr(unsafe.Pointer(hdr))
-
-	pt := unsafe.Pointer(info.loadAddr + uintptr(hdr.e_phoff))
-
-	// We need two things from the segment table: the load offset
-	// and the dynamic table.
-	var foundVaddr bool
-	var dyn *[vdsoDynSize]elfDyn
-	for i := uint16(0); i < hdr.e_phnum; i++ {
-		pt := (*elfPhdr)(add(pt, uintptr(i)*unsafe.Sizeof(elfPhdr{})))
-		switch pt.p_type {
-		case _PT_LOAD:
-			if !foundVaddr {
-				foundVaddr = true
-				info.loadOffset = info.loadAddr + uintptr(pt.p_offset-pt.p_vaddr)
-			}
-
-		case _PT_DYNAMIC:
-			dyn = (*[vdsoDynSize]elfDyn)(unsafe.Pointer(info.loadAddr + uintptr(pt.p_offset)))
-		}
-	}
-
-	if !foundVaddr || dyn == nil {
-		return // Failed
-	}
-
-	// Fish out the useful bits of the dynamic table.
-
-	var hash, gnuhash *[vdsoHashSize]uint32
-	info.symstrings = nil
-	info.symtab = nil
-	info.versym = nil
-	info.verdef = nil
-	for i := 0; dyn[i].d_tag != _DT_NULL; i++ {
-		dt := &dyn[i]
-		p := info.loadOffset + uintptr(dt.d_val)
-		switch dt.d_tag {
-		case _DT_STRTAB:
-			info.symstrings = (*[vdsoSymStringsSize]byte)(unsafe.Pointer(p))
-		case _DT_SYMTAB:
-			info.symtab = (*[vdsoSymTabSize]elfSym)(unsafe.Pointer(p))
-		case _DT_HASH:
-			hash = (*[vdsoHashSize]uint32)(unsafe.Pointer(p))
-		case _DT_GNU_HASH:
-			gnuhash = (*[vdsoHashSize]uint32)(unsafe.Pointer(p))
-		case _DT_VERSYM:
-			info.versym = (*[vdsoVerSymSize]uint16)(unsafe.Pointer(p))
-		case _DT_VERDEF:
-			info.verdef = (*elfVerdef)(unsafe.Pointer(p))
-		}
-	}
-
-	if info.symstrings == nil || info.symtab == nil || (hash == nil && gnuhash == nil) {
-		return // Failed
-	}
-
-	if info.verdef == nil {
-		info.versym = nil
-	}
-
-	if gnuhash != nil {
-		// Parse the GNU hash table header.
-		nbucket := gnuhash[0]
-		info.symOff = gnuhash[1]
-		bloomSize := gnuhash[2]
-		info.bucket = gnuhash[4+bloomSize*uint32(vdsoBloomSizeScale):][:nbucket]
-		info.chain = gnuhash[4+bloomSize*uint32(vdsoBloomSizeScale)+nbucket:]
-		info.isGNUHash = true
-	} else {
-		// Parse the hash table header.
-		nbucket := hash[0]
-		nchain := hash[1]
-		info.bucket = hash[2 : 2+nbucket]
-		info.chain = hash[2+nbucket : 2+nbucket+nchain]
-	}
-
-	// That's all we need.
-	info.valid = true
-}
-
-func vdsoFindVersion(info *vdsoInfo, ver *vdsoVersionKey) int32 {
-	if !info.valid {
-		return 0
-	}
-
-	def := info.verdef
-	for {
-		if def.vd_flags&_VER_FLG_BASE == 0 {
-			aux := (*elfVerdaux)(add(unsafe.Pointer(def), uintptr(def.vd_aux)))
-			if def.vd_hash == ver.verHash && ver.version == gostringnocopy(&info.symstrings[aux.vda_name]) {
-				return int32(def.vd_ndx & 0x7fff)
-			}
-		}
-
-		if def.vd_next == 0 {
-			break
-		}
-		def = (*elfVerdef)(add(unsafe.Pointer(def), uintptr(def.vd_next)))
-	}
-
-	return -1 // cannot match any version
-}
-
-func vdsoParseSymbols(info *vdsoInfo, version int32) {
-	if !info.valid {
-		return
-	}
-
-	apply := func(symIndex uint32, k vdsoSymbolKey) bool {
-		sym := &info.symtab[symIndex]
-		typ := _ELF_ST_TYPE(sym.st_info)
-		bind := _ELF_ST_BIND(sym.st_info)
-		// On ppc64x, VDSO functions are of type _STT_NOTYPE.
-		if typ != _STT_FUNC && typ != _STT_NOTYPE || bind != _STB_GLOBAL && bind != _STB_WEAK || sym.st_shndx == _SHN_UNDEF {
-			return false
-		}
-		if k.name != gostringnocopy(&info.symstrings[sym.st_name]) {
-			return false
-		}
-		// Check symbol version.
-		if info.versym != nil && version != 0 && int32(info.versym[symIndex]&0x7fff) != version {
-			return false
-		}
-
-		*k.ptr = info.loadOffset + uintptr(sym.st_value)
-		return true
-	}
-
-	if !info.isGNUHash {
-		// Old-style DT_HASH table.
-		for _, k := range vdsoSymbolKeys {
-			for chain := info.bucket[k.symHash%uint32(len(info.bucket))]; chain != 0; chain = info.chain[chain] {
-				if apply(chain, k) {
-					break
-				}
-			}
-		}
-		return
-	}
-
-	// New-style DT_GNU_HASH table.
-	for _, k := range vdsoSymbolKeys {
-		symIndex := info.bucket[k.gnuHash%uint32(len(info.bucket))]
-		if symIndex < info.symOff {
-			continue
-		}
-		for ; ; symIndex++ {
-			hash := info.chain[symIndex-info.symOff]
-			if hash|1 == k.gnuHash|1 {
-				// Found a hash match.
-				if apply(symIndex, k) {
-					break
-				}
-			}
-			if hash&1 != 0 {
-				// End of chain.
-				break
-			}
-		}
-	}
-}
-
-func vdsoauxv(tag, val uintptr) {
-	switch tag {
-	case _AT_SYSINFO_EHDR:
-		if val == 0 {
-			// Something went wrong
-			return
-		}
-		var info vdsoInfo
-		// TODO(rsc): I don't understand why the compiler thinks info escapes
-		// when passed to the three functions below.
-		info1 := (*vdsoInfo)(noescape(unsafe.Pointer(&info)))
-		vdsoInitFromSysinfoEhdr(info1, (*elfEhdr)(unsafe.Pointer(val)))
-		vdsoParseSymbols(info1, vdsoFindVersion(info1, &vdsoLinuxVersion))
-	}
-}
-
-// vdsoMarker reports whether PC is on the VDSO page.
-//go:nosplit
-func inVDSOPage(pc uintptr) bool {
-	for _, k := range vdsoSymbolKeys {
-		if *k.ptr != 0 {
-			page := *k.ptr &^ (physPageSize - 1)
-			return pc >= page && pc < page+physPageSize
-		}
-	}
-	return false
-}
diff --git a/contrib/go/_std_1.18/src/sort/search.go b/contrib/go/_std_1.18/src/sort/search.go
deleted file mode 100644
index fcff0f9491..0000000000
--- a/contrib/go/_std_1.18/src/sort/search.go
+++ /dev/null
@@ -1,112 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file implements binary search.
-
-package sort
-
-// Search uses binary search to find and return the smallest index i
-// in [0, n) at which f(i) is true, assuming that on the range [0, n),
-// f(i) == true implies f(i+1) == true. That is, Search requires that
-// f is false for some (possibly empty) prefix of the input range [0, n)
-// and then true for the (possibly empty) remainder; Search returns
-// the first true index. If there is no such index, Search returns n.
-// (Note that the "not found" return value is not -1 as in, for instance,
-// strings.Index.)
-// Search calls f(i) only for i in the range [0, n).
-//
-// A common use of Search is to find the index i for a value x in
-// a sorted, indexable data structure such as an array or slice.
-// In this case, the argument f, typically a closure, captures the value
-// to be searched for, and how the data structure is indexed and
-// ordered.
-//
-// For instance, given a slice data sorted in ascending order,
-// the call Search(len(data), func(i int) bool { return data[i] >= 23 })
-// returns the smallest index i such that data[i] >= 23. If the caller
-// wants to find whether 23 is in the slice, it must test data[i] == 23
-// separately.
-//
-// Searching data sorted in descending order would use the <=
-// operator instead of the >= operator.
-//
-// To complete the example above, the following code tries to find the value
-// x in an integer slice data sorted in ascending order:
-//
-//	x := 23
-//	i := sort.Search(len(data), func(i int) bool { return data[i] >= x })
-//	if i < len(data) && data[i] == x {
-//		// x is present at data[i]
-//	} else {
-//		// x is not present in data,
-//		// but i is the index where it would be inserted.
-//	}
-//
-// As a more whimsical example, this program guesses your number:
-//
-//	func GuessingGame() {
-//		var s string
-//		fmt.Printf("Pick an integer from 0 to 100.\n")
-//		answer := sort.Search(100, func(i int) bool {
-//			fmt.Printf("Is your number <= %d? ", i)
-//			fmt.Scanf("%s", &s)
-//			return s != "" && s[0] == 'y'
-//		})
-//		fmt.Printf("Your number is %d.\n", answer)
-//	}
-//
-func Search(n int, f func(int) bool) int {
-	// Define f(-1) == false and f(n) == true.
-	// Invariant: f(i-1) == false, f(j) == true.
-	i, j := 0, n
-	for i < j {
-		h := int(uint(i+j) >> 1) // avoid overflow when computing h
-		// i ≤ h < j
-		if !f(h) {
-			i = h + 1 // preserves f(i-1) == false
-		} else {
-			j = h // preserves f(j) == true
-		}
-	}
-	// i == j, f(i-1) == false, and f(j) (= f(i)) == true  =>  answer is i.
-	return i
-}
-
-// Convenience wrappers for common cases.
-
-// SearchInts searches for x in a sorted slice of ints and returns the index
-// as specified by Search. The return value is the index to insert x if x is
-// not present (it could be len(a)).
-// The slice must be sorted in ascending order.
-//
-func SearchInts(a []int, x int) int {
-	return Search(len(a), func(i int) bool { return a[i] >= x })
-}
-
-// SearchFloat64s searches for x in a sorted slice of float64s and returns the index
-// as specified by Search. The return value is the index to insert x if x is not
-// present (it could be len(a)).
-// The slice must be sorted in ascending order.
-//
-func SearchFloat64s(a []float64, x float64) int {
-	return Search(len(a), func(i int) bool { return a[i] >= x })
-}
-
-// SearchStrings searches for x in a sorted slice of strings and returns the index
-// as specified by Search. The return value is the index to insert x if x is not
-// present (it could be len(a)).
-// The slice must be sorted in ascending order.
-//
-func SearchStrings(a []string, x string) int {
-	return Search(len(a), func(i int) bool { return a[i] >= x })
-}
-
-// Search returns the result of applying SearchInts to the receiver and x.
-func (p IntSlice) Search(x int) int { return SearchInts(p, x) }
-
-// Search returns the result of applying SearchFloat64s to the receiver and x.
-func (p Float64Slice) Search(x float64) int { return SearchFloat64s(p, x) }
-
-// Search returns the result of applying SearchStrings to the receiver and x.
-func (p StringSlice) Search(x string) int { return SearchStrings(p, x) }
diff --git a/contrib/go/_std_1.18/src/sort/slice.go b/contrib/go/_std_1.18/src/sort/slice.go
deleted file mode 100644
index ba5c2e2f3d..0000000000
--- a/contrib/go/_std_1.18/src/sort/slice.go
+++ /dev/null
@@ -1,46 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package sort
-
-// Slice sorts the slice x given the provided less function.
-// It panics if x is not a slice.
-//
-// The sort is not guaranteed to be stable: equal elements
-// may be reversed from their original order.
-// For a stable sort, use SliceStable.
-//
-// The less function must satisfy the same requirements as
-// the Interface type's Less method.
-func Slice(x any, less func(i, j int) bool) {
-	rv := reflectValueOf(x)
-	swap := reflectSwapper(x)
-	length := rv.Len()
-	quickSort_func(lessSwap{less, swap}, 0, length, maxDepth(length))
-}
-
-// SliceStable sorts the slice x using the provided less
-// function, keeping equal elements in their original order.
-// It panics if x is not a slice.
-//
-// The less function must satisfy the same requirements as
-// the Interface type's Less method.
-func SliceStable(x any, less func(i, j int) bool) {
-	rv := reflectValueOf(x)
-	swap := reflectSwapper(x)
-	stable_func(lessSwap{less, swap}, rv.Len())
-}
-
-// SliceIsSorted reports whether the slice x is sorted according to the provided less function.
-// It panics if x is not a slice.
-func SliceIsSorted(x any, less func(i, j int) bool) bool {
-	rv := reflectValueOf(x)
-	n := rv.Len()
-	for i := n - 1; i > 0; i-- {
-		if less(i, i-1) {
-			return false
-		}
-	}
-	return true
-}
diff --git a/contrib/go/_std_1.18/src/sort/sort.go b/contrib/go/_std_1.18/src/sort/sort.go
deleted file mode 100644
index 749310764a..0000000000
--- a/contrib/go/_std_1.18/src/sort/sort.go
+++ /dev/null
@@ -1,579 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:generate go run genzfunc.go
-
-// Package sort provides primitives for sorting slices and user-defined collections.
-package sort
-
-// An implementation of Interface can be sorted by the routines in this package.
-// The methods refer to elements of the underlying collection by integer index.
-type Interface interface {
-	// Len is the number of elements in the collection.
-	Len() int
-
-	// Less reports whether the element with index i
-	// must sort before the element with index j.
-	//
-	// If both Less(i, j) and Less(j, i) are false,
-	// then the elements at index i and j are considered equal.
-	// Sort may place equal elements in any order in the final result,
-	// while Stable preserves the original input order of equal elements.
-	//
-	// Less must describe a transitive ordering:
-	//  - if both Less(i, j) and Less(j, k) are true, then Less(i, k) must be true as well.
-	//  - if both Less(i, j) and Less(j, k) are false, then Less(i, k) must be false as well.
-	//
-	// Note that floating-point comparison (the < operator on float32 or float64 values)
-	// is not a transitive ordering when not-a-number (NaN) values are involved.
-	// See Float64Slice.Less for a correct implementation for floating-point values.
-	Less(i, j int) bool
-
-	// Swap swaps the elements with indexes i and j.
-	Swap(i, j int)
-}
-
-// insertionSort sorts data[a:b] using insertion sort.
-func insertionSort(data Interface, a, b int) {
-	for i := a + 1; i < b; i++ {
-		for j := i; j > a && data.Less(j, j-1); j-- {
-			data.Swap(j, j-1)
-		}
-	}
-}
-
-// siftDown implements the heap property on data[lo:hi].
-// first is an offset into the array where the root of the heap lies.
-func siftDown(data Interface, lo, hi, first int) {
-	root := lo
-	for {
-		child := 2*root + 1
-		if child >= hi {
-			break
-		}
-		if child+1 < hi && data.Less(first+child, first+child+1) {
-			child++
-		}
-		if !data.Less(first+root, first+child) {
-			return
-		}
-		data.Swap(first+root, first+child)
-		root = child
-	}
-}
-
-func heapSort(data Interface, a, b int) {
-	first := a
-	lo := 0
-	hi := b - a
-
-	// Build heap with greatest element at top.
-	for i := (hi - 1) / 2; i >= 0; i-- {
-		siftDown(data, i, hi, first)
-	}
-
-	// Pop elements, largest first, into end of data.
-	for i := hi - 1; i >= 0; i-- {
-		data.Swap(first, first+i)
-		siftDown(data, lo, i, first)
-	}
-}
-
-// Quicksort, loosely following Bentley and McIlroy,
-// ``Engineering a Sort Function,'' SP&E November 1993.
-
-// medianOfThree moves the median of the three values data[m0], data[m1], data[m2] into data[m1].
-func medianOfThree(data Interface, m1, m0, m2 int) {
-	// sort 3 elements
-	if data.Less(m1, m0) {
-		data.Swap(m1, m0)
-	}
-	// data[m0] <= data[m1]
-	if data.Less(m2, m1) {
-		data.Swap(m2, m1)
-		// data[m0] <= data[m2] && data[m1] < data[m2]
-		if data.Less(m1, m0) {
-			data.Swap(m1, m0)
-		}
-	}
-	// now data[m0] <= data[m1] <= data[m2]
-}
-
-func swapRange(data Interface, a, b, n int) {
-	for i := 0; i < n; i++ {
-		data.Swap(a+i, b+i)
-	}
-}
-
-func doPivot(data Interface, lo, hi int) (midlo, midhi int) {
-	m := int(uint(lo+hi) >> 1) // Written like this to avoid integer overflow.
-	if hi-lo > 40 {
-		// Tukey's ``Ninther,'' median of three medians of three.
-		s := (hi - lo) / 8
-		medianOfThree(data, lo, lo+s, lo+2*s)
-		medianOfThree(data, m, m-s, m+s)
-		medianOfThree(data, hi-1, hi-1-s, hi-1-2*s)
-	}
-	medianOfThree(data, lo, m, hi-1)
-
-	// Invariants are:
-	//	data[lo] = pivot (set up by ChoosePivot)
-	//	data[lo < i < a] < pivot
-	//	data[a <= i < b] <= pivot
-	//	data[b <= i < c] unexamined
-	//	data[c <= i < hi-1] > pivot
-	//	data[hi-1] >= pivot
-	pivot := lo
-	a, c := lo+1, hi-1
-
-	for ; a < c && data.Less(a, pivot); a++ {
-	}
-	b := a
-	for {
-		for ; b < c && !data.Less(pivot, b); b++ { // data[b] <= pivot
-		}
-		for ; b < c && data.Less(pivot, c-1); c-- { // data[c-1] > pivot
-		}
-		if b >= c {
-			break
-		}
-		// data[b] > pivot; data[c-1] <= pivot
-		data.Swap(b, c-1)
-		b++
-		c--
-	}
-	// If hi-c<3 then there are duplicates (by property of median of nine).
-	// Let's be a bit more conservative, and set border to 5.
-	protect := hi-c < 5
-	if !protect && hi-c < (hi-lo)/4 {
-		// Lets test some points for equality to pivot
-		dups := 0
-		if !data.Less(pivot, hi-1) { // data[hi-1] = pivot
-			data.Swap(c, hi-1)
-			c++
-			dups++
-		}
-		if !data.Less(b-1, pivot) { // data[b-1] = pivot
-			b--
-			dups++
-		}
-		// m-lo = (hi-lo)/2 > 6
-		// b-lo > (hi-lo)*3/4-1 > 8
-		// ==> m < b ==> data[m] <= pivot
-		if !data.Less(m, pivot) { // data[m] = pivot
-			data.Swap(m, b-1)
-			b--
-			dups++
-		}
-		// if at least 2 points are equal to pivot, assume skewed distribution
-		protect = dups > 1
-	}
-	if protect {
-		// Protect against a lot of duplicates
-		// Add invariant:
-		//	data[a <= i < b] unexamined
-		//	data[b <= i < c] = pivot
-		for {
-			for ; a < b && !data.Less(b-1, pivot); b-- { // data[b] == pivot
-			}
-			for ; a < b && data.Less(a, pivot); a++ { // data[a] < pivot
-			}
-			if a >= b {
-				break
-			}
-			// data[a] == pivot; data[b-1] < pivot
-			data.Swap(a, b-1)
-			a++
-			b--
-		}
-	}
-	// Swap pivot into middle
-	data.Swap(pivot, b-1)
-	return b - 1, c
-}
-
-func quickSort(data Interface, a, b, maxDepth int) {
-	for b-a > 12 { // Use ShellSort for slices <= 12 elements
-		if maxDepth == 0 {
-			heapSort(data, a, b)
-			return
-		}
-		maxDepth--
-		mlo, mhi := doPivot(data, a, b)
-		// Avoiding recursion on the larger subproblem guarantees
-		// a stack depth of at most lg(b-a).
-		if mlo-a < b-mhi {
-			quickSort(data, a, mlo, maxDepth)
-			a = mhi // i.e., quickSort(data, mhi, b)
-		} else {
-			quickSort(data, mhi, b, maxDepth)
-			b = mlo // i.e., quickSort(data, a, mlo)
-		}
-	}
-	if b-a > 1 {
-		// Do ShellSort pass with gap 6
-		// It could be written in this simplified form cause b-a <= 12
-		for i := a + 6; i < b; i++ {
-			if data.Less(i, i-6) {
-				data.Swap(i, i-6)
-			}
-		}
-		insertionSort(data, a, b)
-	}
-}
-
-// Sort sorts data in ascending order as determined by the Less method.
-// It makes one call to data.Len to determine n and O(n*log(n)) calls to
-// data.Less and data.Swap. The sort is not guaranteed to be stable.
-func Sort(data Interface) {
-	n := data.Len()
-	quickSort(data, 0, n, maxDepth(n))
-}
-
-// maxDepth returns a threshold at which quicksort should switch
-// to heapsort. It returns 2*ceil(lg(n+1)).
-func maxDepth(n int) int {
-	var depth int
-	for i := n; i > 0; i >>= 1 {
-		depth++
-	}
-	return depth * 2
-}
-
-// lessSwap is a pair of Less and Swap function for use with the
-// auto-generated func-optimized variant of sort.go in
-// zfuncversion.go.
-type lessSwap struct {
-	Less func(i, j int) bool
-	Swap func(i, j int)
-}
-
-type reverse struct {
-	// This embedded Interface permits Reverse to use the methods of
-	// another Interface implementation.
-	Interface
-}
-
-// Less returns the opposite of the embedded implementation's Less method.
-func (r reverse) Less(i, j int) bool {
-	return r.Interface.Less(j, i)
-}
-
-// Reverse returns the reverse order for data.
-func Reverse(data Interface) Interface {
-	return &reverse{data}
-}
-
-// IsSorted reports whether data is sorted.
-func IsSorted(data Interface) bool {
-	n := data.Len()
-	for i := n - 1; i > 0; i-- {
-		if data.Less(i, i-1) {
-			return false
-		}
-	}
-	return true
-}
-
-// Convenience types for common cases
-
-// IntSlice attaches the methods of Interface to []int, sorting in increasing order.
-type IntSlice []int
-
-func (x IntSlice) Len() int           { return len(x) }
-func (x IntSlice) Less(i, j int) bool { return x[i] < x[j] }
-func (x IntSlice) Swap(i, j int)      { x[i], x[j] = x[j], x[i] }
-
-// Sort is a convenience method: x.Sort() calls Sort(x).
-func (x IntSlice) Sort() { Sort(x) }
-
-// Float64Slice implements Interface for a []float64, sorting in increasing order,
-// with not-a-number (NaN) values ordered before other values.
-type Float64Slice []float64
-
-func (x Float64Slice) Len() int { return len(x) }
-
-// Less reports whether x[i] should be ordered before x[j], as required by the sort Interface.
-// Note that floating-point comparison by itself is not a transitive relation: it does not
-// report a consistent ordering for not-a-number (NaN) values.
-// This implementation of Less places NaN values before any others, by using:
-//
-//	x[i] < x[j] || (math.IsNaN(x[i]) && !math.IsNaN(x[j]))
-//
-func (x Float64Slice) Less(i, j int) bool { return x[i] < x[j] || (isNaN(x[i]) && !isNaN(x[j])) }
-func (x Float64Slice) Swap(i, j int)      { x[i], x[j] = x[j], x[i] }
-
-// isNaN is a copy of math.IsNaN to avoid a dependency on the math package.
-func isNaN(f float64) bool {
-	return f != f
-}
-
-// Sort is a convenience method: x.Sort() calls Sort(x).
-func (x Float64Slice) Sort() { Sort(x) }
-
-// StringSlice attaches the methods of Interface to []string, sorting in increasing order.
-type StringSlice []string
-
-func (x StringSlice) Len() int           { return len(x) }
-func (x StringSlice) Less(i, j int) bool { return x[i] < x[j] }
-func (x StringSlice) Swap(i, j int)      { x[i], x[j] = x[j], x[i] }
-
-// Sort is a convenience method: x.Sort() calls Sort(x).
-func (x StringSlice) Sort() { Sort(x) }
-
-// Convenience wrappers for common cases
-
-// Ints sorts a slice of ints in increasing order.
-func Ints(x []int) { Sort(IntSlice(x)) }
-
-// Float64s sorts a slice of float64s in increasing order.
-// Not-a-number (NaN) values are ordered before other values.
-func Float64s(x []float64) { Sort(Float64Slice(x)) }
-
-// Strings sorts a slice of strings in increasing order.
-func Strings(x []string) { Sort(StringSlice(x)) }
-
-// IntsAreSorted reports whether the slice x is sorted in increasing order.
-func IntsAreSorted(x []int) bool { return IsSorted(IntSlice(x)) }
-
-// Float64sAreSorted reports whether the slice x is sorted in increasing order,
-// with not-a-number (NaN) values before any other values.
-func Float64sAreSorted(x []float64) bool { return IsSorted(Float64Slice(x)) }
-
-// StringsAreSorted reports whether the slice x is sorted in increasing order.
-func StringsAreSorted(x []string) bool { return IsSorted(StringSlice(x)) }
-
-// Notes on stable sorting:
-// The used algorithms are simple and provable correct on all input and use
-// only logarithmic additional stack space. They perform well if compared
-// experimentally to other stable in-place sorting algorithms.
-//
-// Remarks on other algorithms evaluated:
-//  - GCC's 4.6.3 stable_sort with merge_without_buffer from libstdc++:
-//    Not faster.
-//  - GCC's __rotate for block rotations: Not faster.
-//  - "Practical in-place mergesort" from  Jyrki Katajainen, Tomi A. Pasanen
-//    and Jukka Teuhola; Nordic Journal of Computing 3,1 (1996), 27-40:
-//    The given algorithms are in-place, number of Swap and Assignments
-//    grow as n log n but the algorithm is not stable.
-//  - "Fast Stable In-Place Sorting with O(n) Data Moves" J.I. Munro and
-//    V. Raman in Algorithmica (1996) 16, 115-160:
-//    This algorithm either needs additional 2n bits or works only if there
-//    are enough different elements available to encode some permutations
-//    which have to be undone later (so not stable on any input).
-//  - All the optimal in-place sorting/merging algorithms I found are either
-//    unstable or rely on enough different elements in each step to encode the
-//    performed block rearrangements. See also "In-Place Merging Algorithms",
-//    Denham Coates-Evely, Department of Computer Science, Kings College,
-//    January 2004 and the references in there.
-//  - Often "optimal" algorithms are optimal in the number of assignments
-//    but Interface has only Swap as operation.
-
-// Stable sorts data in ascending order as determined by the Less method,
-// while keeping the original order of equal elements.
-//
-// It makes one call to data.Len to determine n, O(n*log(n)) calls to
-// data.Less and O(n*log(n)*log(n)) calls to data.Swap.
-func Stable(data Interface) {
-	stable(data, data.Len())
-}
-
-func stable(data Interface, n int) {
-	blockSize := 20 // must be > 0
-	a, b := 0, blockSize
-	for b <= n {
-		insertionSort(data, a, b)
-		a = b
-		b += blockSize
-	}
-	insertionSort(data, a, n)
-
-	for blockSize < n {
-		a, b = 0, 2*blockSize
-		for b <= n {
-			symMerge(data, a, a+blockSize, b)
-			a = b
-			b += 2 * blockSize
-		}
-		if m := a + blockSize; m < n {
-			symMerge(data, a, m, n)
-		}
-		blockSize *= 2
-	}
-}
-
-// symMerge merges the two sorted subsequences data[a:m] and data[m:b] using
-// the SymMerge algorithm from Pok-Son Kim and Arne Kutzner, "Stable Minimum
-// Storage Merging by Symmetric Comparisons", in Susanne Albers and Tomasz
-// Radzik, editors, Algorithms - ESA 2004, volume 3221 of Lecture Notes in
-// Computer Science, pages 714-723. Springer, 2004.
-//
-// Let M = m-a and N = b-n. Wolog M < N.
-// The recursion depth is bound by ceil(log(N+M)).
-// The algorithm needs O(M*log(N/M + 1)) calls to data.Less.
-// The algorithm needs O((M+N)*log(M)) calls to data.Swap.
-//
-// The paper gives O((M+N)*log(M)) as the number of assignments assuming a
-// rotation algorithm which uses O(M+N+gcd(M+N)) assignments. The argumentation
-// in the paper carries through for Swap operations, especially as the block
-// swapping rotate uses only O(M+N) Swaps.
-//
-// symMerge assumes non-degenerate arguments: a < m && m < b.
-// Having the caller check this condition eliminates many leaf recursion calls,
-// which improves performance.
-func symMerge(data Interface, a, m, b int) {
-	// Avoid unnecessary recursions of symMerge
-	// by direct insertion of data[a] into data[m:b]
-	// if data[a:m] only contains one element.
-	if m-a == 1 {
-		// Use binary search to find the lowest index i
-		// such that data[i] >= data[a] for m <= i < b.
-		// Exit the search loop with i == b in case no such index exists.
-		i := m
-		j := b
-		for i < j {
-			h := int(uint(i+j) >> 1)
-			if data.Less(h, a) {
-				i = h + 1
-			} else {
-				j = h
-			}
-		}
-		// Swap values until data[a] reaches the position before i.
-		for k := a; k < i-1; k++ {
-			data.Swap(k, k+1)
-		}
-		return
-	}
-
-	// Avoid unnecessary recursions of symMerge
-	// by direct insertion of data[m] into data[a:m]
-	// if data[m:b] only contains one element.
-	if b-m == 1 {
-		// Use binary search to find the lowest index i
-		// such that data[i] > data[m] for a <= i < m.
-		// Exit the search loop with i == m in case no such index exists.
-		i := a
-		j := m
-		for i < j {
-			h := int(uint(i+j) >> 1)
-			if !data.Less(m, h) {
-				i = h + 1
-			} else {
-				j = h
-			}
-		}
-		// Swap values until data[m] reaches the position i.
-		for k := m; k > i; k-- {
-			data.Swap(k, k-1)
-		}
-		return
-	}
-
-	mid := int(uint(a+b) >> 1)
-	n := mid + m
-	var start, r int
-	if m > mid {
-		start = n - b
-		r = mid
-	} else {
-		start = a
-		r = m
-	}
-	p := n - 1
-
-	for start < r {
-		c := int(uint(start+r) >> 1)
-		if !data.Less(p-c, c) {
-			start = c + 1
-		} else {
-			r = c
-		}
-	}
-
-	end := n - start
-	if start < m && m < end {
-		rotate(data, start, m, end)
-	}
-	if a < start && start < mid {
-		symMerge(data, a, start, mid)
-	}
-	if mid < end && end < b {
-		symMerge(data, mid, end, b)
-	}
-}
-
-// rotate rotates two consecutive blocks u = data[a:m] and v = data[m:b] in data:
-// Data of the form 'x u v y' is changed to 'x v u y'.
-// rotate performs at most b-a many calls to data.Swap,
-// and it assumes non-degenerate arguments: a < m && m < b.
-func rotate(data Interface, a, m, b int) {
-	i := m - a
-	j := b - m
-
-	for i != j {
-		if i > j {
-			swapRange(data, m-i, m, j)
-			i -= j
-		} else {
-			swapRange(data, m-i, m+j-i, i)
-			j -= i
-		}
-	}
-	// i == j
-	swapRange(data, m-i, m, i)
-}
-
-/*
-Complexity of Stable Sorting
-
-
-Complexity of block swapping rotation
-
-Each Swap puts one new element into its correct, final position.
-Elements which reach their final position are no longer moved.
-Thus block swapping rotation needs |u|+|v| calls to Swaps.
-This is best possible as each element might need a move.
-
-Pay attention when comparing to other optimal algorithms which
-typically count the number of assignments instead of swaps:
-E.g. the optimal algorithm of Dudzinski and Dydek for in-place
-rotations uses O(u + v + gcd(u,v)) assignments which is
-better than our O(3 * (u+v)) as gcd(u,v) <= u.
-
-
-Stable sorting by SymMerge and BlockSwap rotations
-
-SymMerg complexity for same size input M = N:
-Calls to Less:  O(M*log(N/M+1)) = O(N*log(2)) = O(N)
-Calls to Swap:  O((M+N)*log(M)) = O(2*N*log(N)) = O(N*log(N))
-
-(The following argument does not fuzz over a missing -1 or
-other stuff which does not impact the final result).
-
-Let n = data.Len(). Assume n = 2^k.
-
-Plain merge sort performs log(n) = k iterations.
-On iteration i the algorithm merges 2^(k-i) blocks, each of size 2^i.
-
-Thus iteration i of merge sort performs:
-Calls to Less  O(2^(k-i) * 2^i) = O(2^k) = O(2^log(n)) = O(n)
-Calls to Swap  O(2^(k-i) * 2^i * log(2^i)) = O(2^k * i) = O(n*i)
-
-In total k = log(n) iterations are performed; so in total:
-Calls to Less O(log(n) * n)
-Calls to Swap O(n + 2*n + 3*n + ... + (k-1)*n + k*n)
-   = O((k/2) * k * n) = O(n * k^2) = O(n * log^2(n))
-
-
-Above results should generalize to arbitrary n = 2^k + p
-and should not be influenced by the initial insertion sort phase:
-Insertion sort is O(n^2) on Swap and Less, thus O(bs^2) per block of
-size bs at n/bs blocks:  O(bs*n) Swaps and Less during insertion sort.
-Merge sort iterations start at i = log(bs). With t = log(bs) constant:
-Calls to Less O((log(n)-t) * n + bs*n) = O(log(n)*n + (bs-t)*n)
-   = O(n * log(n))
-Calls to Swap O(n * log^2(n) - (t^2+t)/2*n) = O(n * log^2(n))
-
-*/
diff --git a/contrib/go/_std_1.18/src/sort/zfuncversion.go b/contrib/go/_std_1.18/src/sort/zfuncversion.go
deleted file mode 100644
index 30067cbe07..0000000000
--- a/contrib/go/_std_1.18/src/sort/zfuncversion.go
+++ /dev/null
@@ -1,265 +0,0 @@
-// Code generated from sort.go using genzfunc.go; DO NOT EDIT.
-
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package sort
-
-// Auto-generated variant of sort.go:insertionSort
-func insertionSort_func(data lessSwap, a, b int) {
-	for i := a + 1; i < b; i++ {
-		for j := i; j > a && data.Less(j, j-1); j-- {
-			data.Swap(j, j-1)
-		}
-	}
-}
-
-// Auto-generated variant of sort.go:siftDown
-func siftDown_func(data lessSwap, lo, hi, first int) {
-	root := lo
-	for {
-		child := 2*root + 1
-		if child >= hi {
-			break
-		}
-		if child+1 < hi && data.Less(first+child, first+child+1) {
-			child++
-		}
-		if !data.Less(first+root, first+child) {
-			return
-		}
-		data.Swap(first+root, first+child)
-		root = child
-	}
-}
-
-// Auto-generated variant of sort.go:heapSort
-func heapSort_func(data lessSwap, a, b int) {
-	first := a
-	lo := 0
-	hi := b - a
-	for i := (hi - 1) / 2; i >= 0; i-- {
-		siftDown_func(data, i, hi, first)
-	}
-	for i := hi - 1; i >= 0; i-- {
-		data.Swap(first, first+i)
-		siftDown_func(data, lo, i, first)
-	}
-}
-
-// Auto-generated variant of sort.go:medianOfThree
-func medianOfThree_func(data lessSwap, m1, m0, m2 int) {
-	if data.Less(m1, m0) {
-		data.Swap(m1, m0)
-	}
-	if data.Less(m2, m1) {
-		data.Swap(m2, m1)
-		if data.Less(m1, m0) {
-			data.Swap(m1, m0)
-		}
-	}
-}
-
-// Auto-generated variant of sort.go:swapRange
-func swapRange_func(data lessSwap, a, b, n int) {
-	for i := 0; i < n; i++ {
-		data.Swap(a+i, b+i)
-	}
-}
-
-// Auto-generated variant of sort.go:doPivot
-func doPivot_func(data lessSwap, lo, hi int) (midlo, midhi int) {
-	m := int(uint(lo+hi) >> 1)
-	if hi-lo > 40 {
-		s := (hi - lo) / 8
-		medianOfThree_func(data, lo, lo+s, lo+2*s)
-		medianOfThree_func(data, m, m-s, m+s)
-		medianOfThree_func(data, hi-1, hi-1-s, hi-1-2*s)
-	}
-	medianOfThree_func(data, lo, m, hi-1)
-	pivot := lo
-	a, c := lo+1, hi-1
-	for ; a < c && data.Less(a, pivot); a++ {
-	}
-	b := a
-	for {
-		for ; b < c && !data.Less(pivot, b); b++ {
-		}
-		for ; b < c && data.Less(pivot, c-1); c-- {
-		}
-		if b >= c {
-			break
-		}
-		data.Swap(b, c-1)
-		b++
-		c--
-	}
-	protect := hi-c < 5
-	if !protect && hi-c < (hi-lo)/4 {
-		dups := 0
-		if !data.Less(pivot, hi-1) {
-			data.Swap(c, hi-1)
-			c++
-			dups++
-		}
-		if !data.Less(b-1, pivot) {
-			b--
-			dups++
-		}
-		if !data.Less(m, pivot) {
-			data.Swap(m, b-1)
-			b--
-			dups++
-		}
-		protect = dups > 1
-	}
-	if protect {
-		for {
-			for ; a < b && !data.Less(b-1, pivot); b-- {
-			}
-			for ; a < b && data.Less(a, pivot); a++ {
-			}
-			if a >= b {
-				break
-			}
-			data.Swap(a, b-1)
-			a++
-			b--
-		}
-	}
-	data.Swap(pivot, b-1)
-	return b - 1, c
-}
-
-// Auto-generated variant of sort.go:quickSort
-func quickSort_func(data lessSwap, a, b, maxDepth int) {
-	for b-a > 12 {
-		if maxDepth == 0 {
-			heapSort_func(data, a, b)
-			return
-		}
-		maxDepth--
-		mlo, mhi := doPivot_func(data, a, b)
-		if mlo-a < b-mhi {
-			quickSort_func(data, a, mlo, maxDepth)
-			a = mhi
-		} else {
-			quickSort_func(data, mhi, b, maxDepth)
-			b = mlo
-		}
-	}
-	if b-a > 1 {
-		for i := a + 6; i < b; i++ {
-			if data.Less(i, i-6) {
-				data.Swap(i, i-6)
-			}
-		}
-		insertionSort_func(data, a, b)
-	}
-}
-
-// Auto-generated variant of sort.go:stable
-func stable_func(data lessSwap, n int) {
-	blockSize := 20
-	a, b := 0, blockSize
-	for b <= n {
-		insertionSort_func(data, a, b)
-		a = b
-		b += blockSize
-	}
-	insertionSort_func(data, a, n)
-	for blockSize < n {
-		a, b = 0, 2*blockSize
-		for b <= n {
-			symMerge_func(data, a, a+blockSize, b)
-			a = b
-			b += 2 * blockSize
-		}
-		if m := a + blockSize; m < n {
-			symMerge_func(data, a, m, n)
-		}
-		blockSize *= 2
-	}
-}
-
-// Auto-generated variant of sort.go:symMerge
-func symMerge_func(data lessSwap, a, m, b int) {
-	if m-a == 1 {
-		i := m
-		j := b
-		for i < j {
-			h := int(uint(i+j) >> 1)
-			if data.Less(h, a) {
-				i = h + 1
-			} else {
-				j = h
-			}
-		}
-		for k := a; k < i-1; k++ {
-			data.Swap(k, k+1)
-		}
-		return
-	}
-	if b-m == 1 {
-		i := a
-		j := m
-		for i < j {
-			h := int(uint(i+j) >> 1)
-			if !data.Less(m, h) {
-				i = h + 1
-			} else {
-				j = h
-			}
-		}
-		for k := m; k > i; k-- {
-			data.Swap(k, k-1)
-		}
-		return
-	}
-	mid := int(uint(a+b) >> 1)
-	n := mid + m
-	var start, r int
-	if m > mid {
-		start = n - b
-		r = mid
-	} else {
-		start = a
-		r = m
-	}
-	p := n - 1
-	for start < r {
-		c := int(uint(start+r) >> 1)
-		if !data.Less(p-c, c) {
-			start = c + 1
-		} else {
-			r = c
-		}
-	}
-	end := n - start
-	if start < m && m < end {
-		rotate_func(data, start, m, end)
-	}
-	if a < start && start < mid {
-		symMerge_func(data, a, start, mid)
-	}
-	if mid < end && end < b {
-		symMerge_func(data, mid, end, b)
-	}
-}
-
-// Auto-generated variant of sort.go:rotate
-func rotate_func(data lessSwap, a, m, b int) {
-	i := m - a
-	j := b - m
-	for i != j {
-		if i > j {
-			swapRange_func(data, m-i, m, j)
-			i -= j
-		} else {
-			swapRange_func(data, m-i, m+j-i, i)
-			j -= i
-		}
-	}
-	swapRange_func(data, m-i, m, i)
-}
diff --git a/contrib/go/_std_1.18/src/strconv/atof.go b/contrib/go/_std_1.18/src/strconv/atof.go
deleted file mode 100644
index 57556c7047..0000000000
--- a/contrib/go/_std_1.18/src/strconv/atof.go
+++ /dev/null
@@ -1,704 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package strconv
-
-// decimal to binary floating point conversion.
-// Algorithm:
-//   1) Store input in multiprecision decimal.
-//   2) Multiply/divide decimal by powers of two until in range [0.5, 1)
-//   3) Multiply by 2^precision and round to get mantissa.
-
-import "math"
-
-var optimize = true // set to false to force slow-path conversions for testing
-
-// commonPrefixLenIgnoreCase returns the length of the common
-// prefix of s and prefix, with the character case of s ignored.
-// The prefix argument must be all lower-case.
-func commonPrefixLenIgnoreCase(s, prefix string) int {
-	n := len(prefix)
-	if n > len(s) {
-		n = len(s)
-	}
-	for i := 0; i < n; i++ {
-		c := s[i]
-		if 'A' <= c && c <= 'Z' {
-			c += 'a' - 'A'
-		}
-		if c != prefix[i] {
-			return i
-		}
-	}
-	return n
-}
-
-// special returns the floating-point value for the special,
-// possibly signed floating-point representations inf, infinity,
-// and NaN. The result is ok if a prefix of s contains one
-// of these representations and n is the length of that prefix.
-// The character case is ignored.
-func special(s string) (f float64, n int, ok bool) {
-	if len(s) == 0 {
-		return 0, 0, false
-	}
-	sign := 1
-	nsign := 0
-	switch s[0] {
-	case '+', '-':
-		if s[0] == '-' {
-			sign = -1
-		}
-		nsign = 1
-		s = s[1:]
-		fallthrough
-	case 'i', 'I':
-		n := commonPrefixLenIgnoreCase(s, "infinity")
-		// Anything longer than "inf" is ok, but if we
-		// don't have "infinity", only consume "inf".
-		if 3 < n && n < 8 {
-			n = 3
-		}
-		if n == 3 || n == 8 {
-			return math.Inf(sign), nsign + n, true
-		}
-	case 'n', 'N':
-		if commonPrefixLenIgnoreCase(s, "nan") == 3 {
-			return math.NaN(), 3, true
-		}
-	}
-	return 0, 0, false
-}
-
-func (b *decimal) set(s string) (ok bool) {
-	i := 0
-	b.neg = false
-	b.trunc = false
-
-	// optional sign
-	if i >= len(s) {
-		return
-	}
-	switch {
-	case s[i] == '+':
-		i++
-	case s[i] == '-':
-		b.neg = true
-		i++
-	}
-
-	// digits
-	sawdot := false
-	sawdigits := false
-	for ; i < len(s); i++ {
-		switch {
-		case s[i] == '_':
-			// readFloat already checked underscores
-			continue
-		case s[i] == '.':
-			if sawdot {
-				return
-			}
-			sawdot = true
-			b.dp = b.nd
-			continue
-
-		case '0' <= s[i] && s[i] <= '9':
-			sawdigits = true
-			if s[i] == '0' && b.nd == 0 { // ignore leading zeros
-				b.dp--
-				continue
-			}
-			if b.nd < len(b.d) {
-				b.d[b.nd] = s[i]
-				b.nd++
-			} else if s[i] != '0' {
-				b.trunc = true
-			}
-			continue
-		}
-		break
-	}
-	if !sawdigits {
-		return
-	}
-	if !sawdot {
-		b.dp = b.nd
-	}
-
-	// optional exponent moves decimal point.
-	// if we read a very large, very long number,
-	// just be sure to move the decimal point by
-	// a lot (say, 100000).  it doesn't matter if it's
-	// not the exact number.
-	if i < len(s) && lower(s[i]) == 'e' {
-		i++
-		if i >= len(s) {
-			return
-		}
-		esign := 1
-		if s[i] == '+' {
-			i++
-		} else if s[i] == '-' {
-			i++
-			esign = -1
-		}
-		if i >= len(s) || s[i] < '0' || s[i] > '9' {
-			return
-		}
-		e := 0
-		for ; i < len(s) && ('0' <= s[i] && s[i] <= '9' || s[i] == '_'); i++ {
-			if s[i] == '_' {
-				// readFloat already checked underscores
-				continue
-			}
-			if e < 10000 {
-				e = e*10 + int(s[i]) - '0'
-			}
-		}
-		b.dp += e * esign
-	}
-
-	if i != len(s) {
-		return
-	}
-
-	ok = true
-	return
-}
-
-// readFloat reads a decimal or hexadecimal mantissa and exponent from a float
-// string representation in s; the number may be followed by other characters.
-// readFloat reports the number of bytes consumed (i), and whether the number
-// is valid (ok).
-func readFloat(s string) (mantissa uint64, exp int, neg, trunc, hex bool, i int, ok bool) {
-	underscores := false
-
-	// optional sign
-	if i >= len(s) {
-		return
-	}
-	switch {
-	case s[i] == '+':
-		i++
-	case s[i] == '-':
-		neg = true
-		i++
-	}
-
-	// digits
-	base := uint64(10)
-	maxMantDigits := 19 // 10^19 fits in uint64
-	expChar := byte('e')
-	if i+2 < len(s) && s[i] == '0' && lower(s[i+1]) == 'x' {
-		base = 16
-		maxMantDigits = 16 // 16^16 fits in uint64
-		i += 2
-		expChar = 'p'
-		hex = true
-	}
-	sawdot := false
-	sawdigits := false
-	nd := 0
-	ndMant := 0
-	dp := 0
-loop:
-	for ; i < len(s); i++ {
-		switch c := s[i]; true {
-		case c == '_':
-			underscores = true
-			continue
-
-		case c == '.':
-			if sawdot {
-				break loop
-			}
-			sawdot = true
-			dp = nd
-			continue
-
-		case '0' <= c && c <= '9':
-			sawdigits = true
-			if c == '0' && nd == 0 { // ignore leading zeros
-				dp--
-				continue
-			}
-			nd++
-			if ndMant < maxMantDigits {
-				mantissa *= base
-				mantissa += uint64(c - '0')
-				ndMant++
-			} else if c != '0' {
-				trunc = true
-			}
-			continue
-
-		case base == 16 && 'a' <= lower(c) && lower(c) <= 'f':
-			sawdigits = true
-			nd++
-			if ndMant < maxMantDigits {
-				mantissa *= 16
-				mantissa += uint64(lower(c) - 'a' + 10)
-				ndMant++
-			} else {
-				trunc = true
-			}
-			continue
-		}
-		break
-	}
-	if !sawdigits {
-		return
-	}
-	if !sawdot {
-		dp = nd
-	}
-
-	if base == 16 {
-		dp *= 4
-		ndMant *= 4
-	}
-
-	// optional exponent moves decimal point.
-	// if we read a very large, very long number,
-	// just be sure to move the decimal point by
-	// a lot (say, 100000).  it doesn't matter if it's
-	// not the exact number.
-	if i < len(s) && lower(s[i]) == expChar {
-		i++
-		if i >= len(s) {
-			return
-		}
-		esign := 1
-		if s[i] == '+' {
-			i++
-		} else if s[i] == '-' {
-			i++
-			esign = -1
-		}
-		if i >= len(s) || s[i] < '0' || s[i] > '9' {
-			return
-		}
-		e := 0
-		for ; i < len(s) && ('0' <= s[i] && s[i] <= '9' || s[i] == '_'); i++ {
-			if s[i] == '_' {
-				underscores = true
-				continue
-			}
-			if e < 10000 {
-				e = e*10 + int(s[i]) - '0'
-			}
-		}
-		dp += e * esign
-	} else if base == 16 {
-		// Must have exponent.
-		return
-	}
-
-	if mantissa != 0 {
-		exp = dp - ndMant
-	}
-
-	if underscores && !underscoreOK(s[:i]) {
-		return
-	}
-
-	ok = true
-	return
-}
-
-// decimal power of ten to binary power of two.
-var powtab = []int{1, 3, 6, 9, 13, 16, 19, 23, 26}
-
-func (d *decimal) floatBits(flt *floatInfo) (b uint64, overflow bool) {
-	var exp int
-	var mant uint64
-
-	// Zero is always a special case.
-	if d.nd == 0 {
-		mant = 0
-		exp = flt.bias
-		goto out
-	}
-
-	// Obvious overflow/underflow.
-	// These bounds are for 64-bit floats.
-	// Will have to change if we want to support 80-bit floats in the future.
-	if d.dp > 310 {
-		goto overflow
-	}
-	if d.dp < -330 {
-		// zero
-		mant = 0
-		exp = flt.bias
-		goto out
-	}
-
-	// Scale by powers of two until in range [0.5, 1.0)
-	exp = 0
-	for d.dp > 0 {
-		var n int
-		if d.dp >= len(powtab) {
-			n = 27
-		} else {
-			n = powtab[d.dp]
-		}
-		d.Shift(-n)
-		exp += n
-	}
-	for d.dp < 0 || d.dp == 0 && d.d[0] < '5' {
-		var n int
-		if -d.dp >= len(powtab) {
-			n = 27
-		} else {
-			n = powtab[-d.dp]
-		}
-		d.Shift(n)
-		exp -= n
-	}
-
-	// Our range is [0.5,1) but floating point range is [1,2).
-	exp--
-
-	// Minimum representable exponent is flt.bias+1.
-	// If the exponent is smaller, move it up and
-	// adjust d accordingly.
-	if exp < flt.bias+1 {
-		n := flt.bias + 1 - exp
-		d.Shift(-n)
-		exp += n
-	}
-
-	if exp-flt.bias >= 1<<flt.expbits-1 {
-		goto overflow
-	}
-
-	// Extract 1+flt.mantbits bits.
-	d.Shift(int(1 + flt.mantbits))
-	mant = d.RoundedInteger()
-
-	// Rounding might have added a bit; shift down.
-	if mant == 2<<flt.mantbits {
-		mant >>= 1
-		exp++
-		if exp-flt.bias >= 1<<flt.expbits-1 {
-			goto overflow
-		}
-	}
-
-	// Denormalized?
-	if mant&(1<<flt.mantbits) == 0 {
-		exp = flt.bias
-	}
-	goto out
-
-overflow:
-	// ±Inf
-	mant = 0
-	exp = 1<<flt.expbits - 1 + flt.bias
-	overflow = true
-
-out:
-	// Assemble bits.
-	bits := mant & (uint64(1)<<flt.mantbits - 1)
-	bits |= uint64((exp-flt.bias)&(1<<flt.expbits-1)) << flt.mantbits
-	if d.neg {
-		bits |= 1 << flt.mantbits << flt.expbits
-	}
-	return bits, overflow
-}
-
-// Exact powers of 10.
-var float64pow10 = []float64{
-	1e0, 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9,
-	1e10, 1e11, 1e12, 1e13, 1e14, 1e15, 1e16, 1e17, 1e18, 1e19,
-	1e20, 1e21, 1e22,
-}
-var float32pow10 = []float32{1e0, 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9, 1e10}
-
-// If possible to convert decimal representation to 64-bit float f exactly,
-// entirely in floating-point math, do so, avoiding the expense of decimalToFloatBits.
-// Three common cases:
-//	value is exact integer
-//	value is exact integer * exact power of ten
-//	value is exact integer / exact power of ten
-// These all produce potentially inexact but correctly rounded answers.
-func atof64exact(mantissa uint64, exp int, neg bool) (f float64, ok bool) {
-	if mantissa>>float64info.mantbits != 0 {
-		return
-	}
-	f = float64(mantissa)
-	if neg {
-		f = -f
-	}
-	switch {
-	case exp == 0:
-		// an integer.
-		return f, true
-	// Exact integers are <= 10^15.
-	// Exact powers of ten are <= 10^22.
-	case exp > 0 && exp <= 15+22: // int * 10^k
-		// If exponent is big but number of digits is not,
-		// can move a few zeros into the integer part.
-		if exp > 22 {
-			f *= float64pow10[exp-22]
-			exp = 22
-		}
-		if f > 1e15 || f < -1e15 {
-			// the exponent was really too large.
-			return
-		}
-		return f * float64pow10[exp], true
-	case exp < 0 && exp >= -22: // int / 10^k
-		return f / float64pow10[-exp], true
-	}
-	return
-}
-
-// If possible to compute mantissa*10^exp to 32-bit float f exactly,
-// entirely in floating-point math, do so, avoiding the machinery above.
-func atof32exact(mantissa uint64, exp int, neg bool) (f float32, ok bool) {
-	if mantissa>>float32info.mantbits != 0 {
-		return
-	}
-	f = float32(mantissa)
-	if neg {
-		f = -f
-	}
-	switch {
-	case exp == 0:
-		return f, true
-	// Exact integers are <= 10^7.
-	// Exact powers of ten are <= 10^10.
-	case exp > 0 && exp <= 7+10: // int * 10^k
-		// If exponent is big but number of digits is not,
-		// can move a few zeros into the integer part.
-		if exp > 10 {
-			f *= float32pow10[exp-10]
-			exp = 10
-		}
-		if f > 1e7 || f < -1e7 {
-			// the exponent was really too large.
-			return
-		}
-		return f * float32pow10[exp], true
-	case exp < 0 && exp >= -10: // int / 10^k
-		return f / float32pow10[-exp], true
-	}
-	return
-}
-
-// atofHex converts the hex floating-point string s
-// to a rounded float32 or float64 value (depending on flt==&float32info or flt==&float64info)
-// and returns it as a float64.
-// The string s has already been parsed into a mantissa, exponent, and sign (neg==true for negative).
-// If trunc is true, trailing non-zero bits have been omitted from the mantissa.
-func atofHex(s string, flt *floatInfo, mantissa uint64, exp int, neg, trunc bool) (float64, error) {
-	maxExp := 1<<flt.expbits + flt.bias - 2
-	minExp := flt.bias + 1
-	exp += int(flt.mantbits) // mantissa now implicitly divided by 2^mantbits.
-
-	// Shift mantissa and exponent to bring representation into float range.
-	// Eventually we want a mantissa with a leading 1-bit followed by mantbits other bits.
-	// For rounding, we need two more, where the bottom bit represents
-	// whether that bit or any later bit was non-zero.
-	// (If the mantissa has already lost non-zero bits, trunc is true,
-	// and we OR in a 1 below after shifting left appropriately.)
-	for mantissa != 0 && mantissa>>(flt.mantbits+2) == 0 {
-		mantissa <<= 1
-		exp--
-	}
-	if trunc {
-		mantissa |= 1
-	}
-	for mantissa>>(1+flt.mantbits+2) != 0 {
-		mantissa = mantissa>>1 | mantissa&1
-		exp++
-	}
-
-	// If exponent is too negative,
-	// denormalize in hopes of making it representable.
-	// (The -2 is for the rounding bits.)
-	for mantissa > 1 && exp < minExp-2 {
-		mantissa = mantissa>>1 | mantissa&1
-		exp++
-	}
-
-	// Round using two bottom bits.
-	round := mantissa & 3
-	mantissa >>= 2
-	round |= mantissa & 1 // round to even (round up if mantissa is odd)
-	exp += 2
-	if round == 3 {
-		mantissa++
-		if mantissa == 1<<(1+flt.mantbits) {
-			mantissa >>= 1
-			exp++
-		}
-	}
-
-	if mantissa>>flt.mantbits == 0 { // Denormal or zero.
-		exp = flt.bias
-	}
-	var err error
-	if exp > maxExp { // infinity and range error
-		mantissa = 1 << flt.mantbits
-		exp = maxExp + 1
-		err = rangeError(fnParseFloat, s)
-	}
-
-	bits := mantissa & (1<<flt.mantbits - 1)
-	bits |= uint64((exp-flt.bias)&(1<<flt.expbits-1)) << flt.mantbits
-	if neg {
-		bits |= 1 << flt.mantbits << flt.expbits
-	}
-	if flt == &float32info {
-		return float64(math.Float32frombits(uint32(bits))), err
-	}
-	return math.Float64frombits(bits), err
-}
-
-const fnParseFloat = "ParseFloat"
-
-func atof32(s string) (f float32, n int, err error) {
-	if val, n, ok := special(s); ok {
-		return float32(val), n, nil
-	}
-
-	mantissa, exp, neg, trunc, hex, n, ok := readFloat(s)
-	if !ok {
-		return 0, n, syntaxError(fnParseFloat, s)
-	}
-
-	if hex {
-		f, err := atofHex(s[:n], &float32info, mantissa, exp, neg, trunc)
-		return float32(f), n, err
-	}
-
-	if optimize {
-		// Try pure floating-point arithmetic conversion, and if that fails,
-		// the Eisel-Lemire algorithm.
-		if !trunc {
-			if f, ok := atof32exact(mantissa, exp, neg); ok {
-				return f, n, nil
-			}
-		}
-		f, ok := eiselLemire32(mantissa, exp, neg)
-		if ok {
-			if !trunc {
-				return f, n, nil
-			}
-			// Even if the mantissa was truncated, we may
-			// have found the correct result. Confirm by
-			// converting the upper mantissa bound.
-			fUp, ok := eiselLemire32(mantissa+1, exp, neg)
-			if ok && f == fUp {
-				return f, n, nil
-			}
-		}
-	}
-
-	// Slow fallback.
-	var d decimal
-	if !d.set(s[:n]) {
-		return 0, n, syntaxError(fnParseFloat, s)
-	}
-	b, ovf := d.floatBits(&float32info)
-	f = math.Float32frombits(uint32(b))
-	if ovf {
-		err = rangeError(fnParseFloat, s)
-	}
-	return f, n, err
-}
-
-func atof64(s string) (f float64, n int, err error) {
-	if val, n, ok := special(s); ok {
-		return val, n, nil
-	}
-
-	mantissa, exp, neg, trunc, hex, n, ok := readFloat(s)
-	if !ok {
-		return 0, n, syntaxError(fnParseFloat, s)
-	}
-
-	if hex {
-		f, err := atofHex(s[:n], &float64info, mantissa, exp, neg, trunc)
-		return f, n, err
-	}
-
-	if optimize {
-		// Try pure floating-point arithmetic conversion, and if that fails,
-		// the Eisel-Lemire algorithm.
-		if !trunc {
-			if f, ok := atof64exact(mantissa, exp, neg); ok {
-				return f, n, nil
-			}
-		}
-		f, ok := eiselLemire64(mantissa, exp, neg)
-		if ok {
-			if !trunc {
-				return f, n, nil
-			}
-			// Even if the mantissa was truncated, we may
-			// have found the correct result. Confirm by
-			// converting the upper mantissa bound.
-			fUp, ok := eiselLemire64(mantissa+1, exp, neg)
-			if ok && f == fUp {
-				return f, n, nil
-			}
-		}
-	}
-
-	// Slow fallback.
-	var d decimal
-	if !d.set(s[:n]) {
-		return 0, n, syntaxError(fnParseFloat, s)
-	}
-	b, ovf := d.floatBits(&float64info)
-	f = math.Float64frombits(b)
-	if ovf {
-		err = rangeError(fnParseFloat, s)
-	}
-	return f, n, err
-}
-
-// ParseFloat converts the string s to a floating-point number
-// with the precision specified by bitSize: 32 for float32, or 64 for float64.
-// When bitSize=32, the result still has type float64, but it will be
-// convertible to float32 without changing its value.
-//
-// ParseFloat accepts decimal and hexadecimal floating-point number syntax.
-// If s is well-formed and near a valid floating-point number,
-// ParseFloat returns the nearest floating-point number rounded
-// using IEEE754 unbiased rounding.
-// (Parsing a hexadecimal floating-point value only rounds when
-// there are more bits in the hexadecimal representation than
-// will fit in the mantissa.)
-//
-// The errors that ParseFloat returns have concrete type *NumError
-// and include err.Num = s.
-//
-// If s is not syntactically well-formed, ParseFloat returns err.Err = ErrSyntax.
-//
-// If s is syntactically well-formed but is more than 1/2 ULP
-// away from the largest floating point number of the given size,
-// ParseFloat returns f = ±Inf, err.Err = ErrRange.
-//
-// ParseFloat recognizes the strings "NaN", and the (possibly signed) strings "Inf" and "Infinity"
-// as their respective special floating point values. It ignores case when matching.
-func ParseFloat(s string, bitSize int) (float64, error) {
-	f, n, err := parseFloatPrefix(s, bitSize)
-	if n != len(s) && (err == nil || err.(*NumError).Err != ErrSyntax) {
-		return 0, syntaxError(fnParseFloat, s)
-	}
-	return f, err
-}
-
-func parseFloatPrefix(s string, bitSize int) (float64, int, error) {
-	if bitSize == 32 {
-		f, n, err := atof32(s)
-		return float64(f), n, err
-	}
-	return atof64(s)
-}
diff --git a/contrib/go/_std_1.18/src/strconv/atoi.go b/contrib/go/_std_1.18/src/strconv/atoi.go
deleted file mode 100644
index 631b487d97..0000000000
--- a/contrib/go/_std_1.18/src/strconv/atoi.go
+++ /dev/null
@@ -1,314 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package strconv
-
-import "errors"
-
-// lower(c) is a lower-case letter if and only if
-// c is either that lower-case letter or the equivalent upper-case letter.
-// Instead of writing c == 'x' || c == 'X' one can write lower(c) == 'x'.
-// Note that lower of non-letters can produce other non-letters.
-func lower(c byte) byte {
-	return c | ('x' - 'X')
-}
-
-// ErrRange indicates that a value is out of range for the target type.
-var ErrRange = errors.New("value out of range")
-
-// ErrSyntax indicates that a value does not have the right syntax for the target type.
-var ErrSyntax = errors.New("invalid syntax")
-
-// A NumError records a failed conversion.
-type NumError struct {
-	Func string // the failing function (ParseBool, ParseInt, ParseUint, ParseFloat, ParseComplex)
-	Num  string // the input
-	Err  error  // the reason the conversion failed (e.g. ErrRange, ErrSyntax, etc.)
-}
-
-func (e *NumError) Error() string {
-	return "strconv." + e.Func + ": " + "parsing " + Quote(e.Num) + ": " + e.Err.Error()
-}
-
-func (e *NumError) Unwrap() error { return e.Err }
-
-func syntaxError(fn, str string) *NumError {
-	return &NumError{fn, str, ErrSyntax}
-}
-
-func rangeError(fn, str string) *NumError {
-	return &NumError{fn, str, ErrRange}
-}
-
-func baseError(fn, str string, base int) *NumError {
-	return &NumError{fn, str, errors.New("invalid base " + Itoa(base))}
-}
-
-func bitSizeError(fn, str string, bitSize int) *NumError {
-	return &NumError{fn, str, errors.New("invalid bit size " + Itoa(bitSize))}
-}
-
-const intSize = 32 << (^uint(0) >> 63)
-
-// IntSize is the size in bits of an int or uint value.
-const IntSize = intSize
-
-const maxUint64 = 1<<64 - 1
-
-// ParseUint is like ParseInt but for unsigned numbers.
-//
-// A sign prefix is not permitted.
-func ParseUint(s string, base int, bitSize int) (uint64, error) {
-	const fnParseUint = "ParseUint"
-
-	if s == "" {
-		return 0, syntaxError(fnParseUint, s)
-	}
-
-	base0 := base == 0
-
-	s0 := s
-	switch {
-	case 2 <= base && base <= 36:
-		// valid base; nothing to do
-
-	case base == 0:
-		// Look for octal, hex prefix.
-		base = 10
-		if s[0] == '0' {
-			switch {
-			case len(s) >= 3 && lower(s[1]) == 'b':
-				base = 2
-				s = s[2:]
-			case len(s) >= 3 && lower(s[1]) == 'o':
-				base = 8
-				s = s[2:]
-			case len(s) >= 3 && lower(s[1]) == 'x':
-				base = 16
-				s = s[2:]
-			default:
-				base = 8
-				s = s[1:]
-			}
-		}
-
-	default:
-		return 0, baseError(fnParseUint, s0, base)
-	}
-
-	if bitSize == 0 {
-		bitSize = IntSize
-	} else if bitSize < 0 || bitSize > 64 {
-		return 0, bitSizeError(fnParseUint, s0, bitSize)
-	}
-
-	// Cutoff is the smallest number such that cutoff*base > maxUint64.
-	// Use compile-time constants for common cases.
-	var cutoff uint64
-	switch base {
-	case 10:
-		cutoff = maxUint64/10 + 1
-	case 16:
-		cutoff = maxUint64/16 + 1
-	default:
-		cutoff = maxUint64/uint64(base) + 1
-	}
-
-	maxVal := uint64(1)<<uint(bitSize) - 1
-
-	underscores := false
-	var n uint64
-	for _, c := range []byte(s) {
-		var d byte
-		switch {
-		case c == '_' && base0:
-			underscores = true
-			continue
-		case '0' <= c && c <= '9':
-			d = c - '0'
-		case 'a' <= lower(c) && lower(c) <= 'z':
-			d = lower(c) - 'a' + 10
-		default:
-			return 0, syntaxError(fnParseUint, s0)
-		}
-
-		if d >= byte(base) {
-			return 0, syntaxError(fnParseUint, s0)
-		}
-
-		if n >= cutoff {
-			// n*base overflows
-			return maxVal, rangeError(fnParseUint, s0)
-		}
-		n *= uint64(base)
-
-		n1 := n + uint64(d)
-		if n1 < n || n1 > maxVal {
-			// n+d overflows
-			return maxVal, rangeError(fnParseUint, s0)
-		}
-		n = n1
-	}
-
-	if underscores && !underscoreOK(s0) {
-		return 0, syntaxError(fnParseUint, s0)
-	}
-
-	return n, nil
-}
-
-// ParseInt interprets a string s in the given base (0, 2 to 36) and
-// bit size (0 to 64) and returns the corresponding value i.
-//
-// The string may begin with a leading sign: "+" or "-".
-//
-// If the base argument is 0, the true base is implied by the string's
-// prefix following the sign (if present): 2 for "0b", 8 for "0" or "0o",
-// 16 for "0x", and 10 otherwise. Also, for argument base 0 only,
-// underscore characters are permitted as defined by the Go syntax for
-// integer literals.
-//
-// The bitSize argument specifies the integer type
-// that the result must fit into. Bit sizes 0, 8, 16, 32, and 64
-// correspond to int, int8, int16, int32, and int64.
-// If bitSize is below 0 or above 64, an error is returned.
-//
-// The errors that ParseInt returns have concrete type *NumError
-// and include err.Num = s. If s is empty or contains invalid
-// digits, err.Err = ErrSyntax and the returned value is 0;
-// if the value corresponding to s cannot be represented by a
-// signed integer of the given size, err.Err = ErrRange and the
-// returned value is the maximum magnitude integer of the
-// appropriate bitSize and sign.
-func ParseInt(s string, base int, bitSize int) (i int64, err error) {
-	const fnParseInt = "ParseInt"
-
-	if s == "" {
-		return 0, syntaxError(fnParseInt, s)
-	}
-
-	// Pick off leading sign.
-	s0 := s
-	neg := false
-	if s[0] == '+' {
-		s = s[1:]
-	} else if s[0] == '-' {
-		neg = true
-		s = s[1:]
-	}
-
-	// Convert unsigned and check range.
-	var un uint64
-	un, err = ParseUint(s, base, bitSize)
-	if err != nil && err.(*NumError).Err != ErrRange {
-		err.(*NumError).Func = fnParseInt
-		err.(*NumError).Num = s0
-		return 0, err
-	}
-
-	if bitSize == 0 {
-		bitSize = IntSize
-	}
-
-	cutoff := uint64(1 << uint(bitSize-1))
-	if !neg && un >= cutoff {
-		return int64(cutoff - 1), rangeError(fnParseInt, s0)
-	}
-	if neg && un > cutoff {
-		return -int64(cutoff), rangeError(fnParseInt, s0)
-	}
-	n := int64(un)
-	if neg {
-		n = -n
-	}
-	return n, nil
-}
-
-// Atoi is equivalent to ParseInt(s, 10, 0), converted to type int.
-func Atoi(s string) (int, error) {
-	const fnAtoi = "Atoi"
-
-	sLen := len(s)
-	if intSize == 32 && (0 < sLen && sLen < 10) ||
-		intSize == 64 && (0 < sLen && sLen < 19) {
-		// Fast path for small integers that fit int type.
-		s0 := s
-		if s[0] == '-' || s[0] == '+' {
-			s = s[1:]
-			if len(s) < 1 {
-				return 0, &NumError{fnAtoi, s0, ErrSyntax}
-			}
-		}
-
-		n := 0
-		for _, ch := range []byte(s) {
-			ch -= '0'
-			if ch > 9 {
-				return 0, &NumError{fnAtoi, s0, ErrSyntax}
-			}
-			n = n*10 + int(ch)
-		}
-		if s0[0] == '-' {
-			n = -n
-		}
-		return n, nil
-	}
-
-	// Slow path for invalid, big, or underscored integers.
-	i64, err := ParseInt(s, 10, 0)
-	if nerr, ok := err.(*NumError); ok {
-		nerr.Func = fnAtoi
-	}
-	return int(i64), err
-}
-
-// underscoreOK reports whether the underscores in s are allowed.
-// Checking them in this one function lets all the parsers skip over them simply.
-// Underscore must appear only between digits or between a base prefix and a digit.
-func underscoreOK(s string) bool {
-	// saw tracks the last character (class) we saw:
-	// ^ for beginning of number,
-	// 0 for a digit or base prefix,
-	// _ for an underscore,
-	// ! for none of the above.
-	saw := '^'
-	i := 0
-
-	// Optional sign.
-	if len(s) >= 1 && (s[0] == '-' || s[0] == '+') {
-		s = s[1:]
-	}
-
-	// Optional base prefix.
-	hex := false
-	if len(s) >= 2 && s[0] == '0' && (lower(s[1]) == 'b' || lower(s[1]) == 'o' || lower(s[1]) == 'x') {
-		i = 2
-		saw = '0' // base prefix counts as a digit for "underscore as digit separator"
-		hex = lower(s[1]) == 'x'
-	}
-
-	// Number proper.
-	for ; i < len(s); i++ {
-		// Digits are always okay.
-		if '0' <= s[i] && s[i] <= '9' || hex && 'a' <= lower(s[i]) && lower(s[i]) <= 'f' {
-			saw = '0'
-			continue
-		}
-		// Underscore must follow digit.
-		if s[i] == '_' {
-			if saw != '0' {
-				return false
-			}
-			saw = '_'
-			continue
-		}
-		// Underscore must also be followed by digit.
-		if saw == '_' {
-			return false
-		}
-		// Saw non-digit, non-underscore.
-		saw = '!'
-	}
-	return saw != '_'
-}
diff --git a/contrib/go/_std_1.18/src/strconv/doc.go b/contrib/go/_std_1.18/src/strconv/doc.go
deleted file mode 100644
index 8db725f96a..0000000000
--- a/contrib/go/_std_1.18/src/strconv/doc.go
+++ /dev/null
@@ -1,57 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package strconv implements conversions to and from string representations
-// of basic data types.
-//
-// Numeric Conversions
-//
-// The most common numeric conversions are Atoi (string to int) and Itoa (int to string).
-//
-//	i, err := strconv.Atoi("-42")
-//	s := strconv.Itoa(-42)
-//
-// These assume decimal and the Go int type.
-//
-// ParseBool, ParseFloat, ParseInt, and ParseUint convert strings to values:
-//
-//	b, err := strconv.ParseBool("true")
-//	f, err := strconv.ParseFloat("3.1415", 64)
-//	i, err := strconv.ParseInt("-42", 10, 64)
-//	u, err := strconv.ParseUint("42", 10, 64)
-//
-// The parse functions return the widest type (float64, int64, and uint64),
-// but if the size argument specifies a narrower width the result can be
-// converted to that narrower type without data loss:
-//
-//	s := "2147483647" // biggest int32
-//	i64, err := strconv.ParseInt(s, 10, 32)
-//	...
-//	i := int32(i64)
-//
-// FormatBool, FormatFloat, FormatInt, and FormatUint convert values to strings:
-//
-//	s := strconv.FormatBool(true)
-//	s := strconv.FormatFloat(3.1415, 'E', -1, 64)
-//	s := strconv.FormatInt(-42, 16)
-//	s := strconv.FormatUint(42, 16)
-//
-// AppendBool, AppendFloat, AppendInt, and AppendUint are similar but
-// append the formatted value to a destination slice.
-//
-// String Conversions
-//
-// Quote and QuoteToASCII convert strings to quoted Go string literals.
-// The latter guarantees that the result is an ASCII string, by escaping
-// any non-ASCII Unicode with \u:
-//
-//	q := strconv.Quote("Hello, 世界")
-//	q := strconv.QuoteToASCII("Hello, 世界")
-//
-// QuoteRune and QuoteRuneToASCII are similar but accept runes and
-// return quoted Go rune literals.
-//
-// Unquote and UnquoteChar unquote Go string and rune literals.
-//
-package strconv
diff --git a/contrib/go/_std_1.18/src/strconv/eisel_lemire.go b/contrib/go/_std_1.18/src/strconv/eisel_lemire.go
deleted file mode 100644
index fecd1b9345..0000000000
--- a/contrib/go/_std_1.18/src/strconv/eisel_lemire.go
+++ /dev/null
@@ -1,884 +0,0 @@
-// Copyright 2020 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package strconv
-
-// This file implements the Eisel-Lemire ParseFloat algorithm, published in
-// 2020 and discussed extensively at
-// https://nigeltao.github.io/blog/2020/eisel-lemire.html
-//
-// The original C++ implementation is at
-// https://github.com/lemire/fast_double_parser/blob/644bef4306059d3be01a04e77d3cc84b379c596f/include/fast_double_parser.h#L840
-//
-// This Go re-implementation closely follows the C re-implementation at
-// https://github.com/google/wuffs/blob/ba3818cb6b473a2ed0b38ecfc07dbbd3a97e8ae7/internal/cgen/base/floatconv-submodule-code.c#L990
-//
-// Additional testing (on over several million test strings) is done by
-// https://github.com/nigeltao/parse-number-fxx-test-data/blob/5280dcfccf6d0b02a65ae282dad0b6d9de50e039/script/test-go-strconv.go
-
-import (
-	"math"
-	"math/bits"
-)
-
-func eiselLemire64(man uint64, exp10 int, neg bool) (f float64, ok bool) {
-	// The terse comments in this function body refer to sections of the
-	// https://nigeltao.github.io/blog/2020/eisel-lemire.html blog post.
-
-	// Exp10 Range.
-	if man == 0 {
-		if neg {
-			f = math.Float64frombits(0x8000000000000000) // Negative zero.
-		}
-		return f, true
-	}
-	if exp10 < detailedPowersOfTenMinExp10 || detailedPowersOfTenMaxExp10 < exp10 {
-		return 0, false
-	}
-
-	// Normalization.
-	clz := bits.LeadingZeros64(man)
-	man <<= uint(clz)
-	const float64ExponentBias = 1023
-	retExp2 := uint64(217706*exp10>>16+64+float64ExponentBias) - uint64(clz)
-
-	// Multiplication.
-	xHi, xLo := bits.Mul64(man, detailedPowersOfTen[exp10-detailedPowersOfTenMinExp10][1])
-
-	// Wider Approximation.
-	if xHi&0x1FF == 0x1FF && xLo+man < man {
-		yHi, yLo := bits.Mul64(man, detailedPowersOfTen[exp10-detailedPowersOfTenMinExp10][0])
-		mergedHi, mergedLo := xHi, xLo+yHi
-		if mergedLo < xLo {
-			mergedHi++
-		}
-		if mergedHi&0x1FF == 0x1FF && mergedLo+1 == 0 && yLo+man < man {
-			return 0, false
-		}
-		xHi, xLo = mergedHi, mergedLo
-	}
-
-	// Shifting to 54 Bits.
-	msb := xHi >> 63
-	retMantissa := xHi >> (msb + 9)
-	retExp2 -= 1 ^ msb
-
-	// Half-way Ambiguity.
-	if xLo == 0 && xHi&0x1FF == 0 && retMantissa&3 == 1 {
-		return 0, false
-	}
-
-	// From 54 to 53 Bits.
-	retMantissa += retMantissa & 1
-	retMantissa >>= 1
-	if retMantissa>>53 > 0 {
-		retMantissa >>= 1
-		retExp2 += 1
-	}
-	// retExp2 is a uint64. Zero or underflow means that we're in subnormal
-	// float64 space. 0x7FF or above means that we're in Inf/NaN float64 space.
-	//
-	// The if block is equivalent to (but has fewer branches than):
-	//   if retExp2 <= 0 || retExp2 >= 0x7FF { etc }
-	if retExp2-1 >= 0x7FF-1 {
-		return 0, false
-	}
-	retBits := retExp2<<52 | retMantissa&0x000FFFFFFFFFFFFF
-	if neg {
-		retBits |= 0x8000000000000000
-	}
-	return math.Float64frombits(retBits), true
-}
-
-func eiselLemire32(man uint64, exp10 int, neg bool) (f float32, ok bool) {
-	// The terse comments in this function body refer to sections of the
-	// https://nigeltao.github.io/blog/2020/eisel-lemire.html blog post.
-	//
-	// That blog post discusses the float64 flavor (11 exponent bits with a
-	// -1023 bias, 52 mantissa bits) of the algorithm, but the same approach
-	// applies to the float32 flavor (8 exponent bits with a -127 bias, 23
-	// mantissa bits). The computation here happens with 64-bit values (e.g.
-	// man, xHi, retMantissa) before finally converting to a 32-bit float.
-
-	// Exp10 Range.
-	if man == 0 {
-		if neg {
-			f = math.Float32frombits(0x80000000) // Negative zero.
-		}
-		return f, true
-	}
-	if exp10 < detailedPowersOfTenMinExp10 || detailedPowersOfTenMaxExp10 < exp10 {
-		return 0, false
-	}
-
-	// Normalization.
-	clz := bits.LeadingZeros64(man)
-	man <<= uint(clz)
-	const float32ExponentBias = 127
-	retExp2 := uint64(217706*exp10>>16+64+float32ExponentBias) - uint64(clz)
-
-	// Multiplication.
-	xHi, xLo := bits.Mul64(man, detailedPowersOfTen[exp10-detailedPowersOfTenMinExp10][1])
-
-	// Wider Approximation.
-	if xHi&0x3FFFFFFFFF == 0x3FFFFFFFFF && xLo+man < man {
-		yHi, yLo := bits.Mul64(man, detailedPowersOfTen[exp10-detailedPowersOfTenMinExp10][0])
-		mergedHi, mergedLo := xHi, xLo+yHi
-		if mergedLo < xLo {
-			mergedHi++
-		}
-		if mergedHi&0x3FFFFFFFFF == 0x3FFFFFFFFF && mergedLo+1 == 0 && yLo+man < man {
-			return 0, false
-		}
-		xHi, xLo = mergedHi, mergedLo
-	}
-
-	// Shifting to 54 Bits (and for float32, it's shifting to 25 bits).
-	msb := xHi >> 63
-	retMantissa := xHi >> (msb + 38)
-	retExp2 -= 1 ^ msb
-
-	// Half-way Ambiguity.
-	if xLo == 0 && xHi&0x3FFFFFFFFF == 0 && retMantissa&3 == 1 {
-		return 0, false
-	}
-
-	// From 54 to 53 Bits (and for float32, it's from 25 to 24 bits).
-	retMantissa += retMantissa & 1
-	retMantissa >>= 1
-	if retMantissa>>24 > 0 {
-		retMantissa >>= 1
-		retExp2 += 1
-	}
-	// retExp2 is a uint64. Zero or underflow means that we're in subnormal
-	// float32 space. 0xFF or above means that we're in Inf/NaN float32 space.
-	//
-	// The if block is equivalent to (but has fewer branches than):
-	//   if retExp2 <= 0 || retExp2 >= 0xFF { etc }
-	if retExp2-1 >= 0xFF-1 {
-		return 0, false
-	}
-	retBits := retExp2<<23 | retMantissa&0x007FFFFF
-	if neg {
-		retBits |= 0x80000000
-	}
-	return math.Float32frombits(uint32(retBits)), true
-}
-
-// detailedPowersOfTen{Min,Max}Exp10 is the power of 10 represented by the
-// first and last rows of detailedPowersOfTen. Both bounds are inclusive.
-const (
-	detailedPowersOfTenMinExp10 = -348
-	detailedPowersOfTenMaxExp10 = +347
-)
-
-// detailedPowersOfTen contains 128-bit mantissa approximations (rounded down)
-// to the powers of 10. For example:
-//
-//  - 1e43 ≈ (0xE596B7B0_C643C719                   * (2 ** 79))
-//  - 1e43 = (0xE596B7B0_C643C719_6D9CCD05_D0000000 * (2 ** 15))
-//
-// The mantissas are explicitly listed. The exponents are implied by a linear
-// expression with slope 217706.0/65536.0 ≈ log(10)/log(2).
-//
-// The table was generated by
-// https://github.com/google/wuffs/blob/ba3818cb6b473a2ed0b38ecfc07dbbd3a97e8ae7/script/print-mpb-powers-of-10.go
-var detailedPowersOfTen = [...][2]uint64{
-	{0x1732C869CD60E453, 0xFA8FD5A0081C0288}, // 1e-348
-	{0x0E7FBD42205C8EB4, 0x9C99E58405118195}, // 1e-347
-	{0x521FAC92A873B261, 0xC3C05EE50655E1FA}, // 1e-346
-	{0xE6A797B752909EF9, 0xF4B0769E47EB5A78}, // 1e-345
-	{0x9028BED2939A635C, 0x98EE4A22ECF3188B}, // 1e-344
-	{0x7432EE873880FC33, 0xBF29DCABA82FDEAE}, // 1e-343
-	{0x113FAA2906A13B3F, 0xEEF453D6923BD65A}, // 1e-342
-	{0x4AC7CA59A424C507, 0x9558B4661B6565F8}, // 1e-341
-	{0x5D79BCF00D2DF649, 0xBAAEE17FA23EBF76}, // 1e-340
-	{0xF4D82C2C107973DC, 0xE95A99DF8ACE6F53}, // 1e-339
-	{0x79071B9B8A4BE869, 0x91D8A02BB6C10594}, // 1e-338
-	{0x9748E2826CDEE284, 0xB64EC836A47146F9}, // 1e-337
-	{0xFD1B1B2308169B25, 0xE3E27A444D8D98B7}, // 1e-336
-	{0xFE30F0F5E50E20F7, 0x8E6D8C6AB0787F72}, // 1e-335
-	{0xBDBD2D335E51A935, 0xB208EF855C969F4F}, // 1e-334
-	{0xAD2C788035E61382, 0xDE8B2B66B3BC4723}, // 1e-333
-	{0x4C3BCB5021AFCC31, 0x8B16FB203055AC76}, // 1e-332
-	{0xDF4ABE242A1BBF3D, 0xADDCB9E83C6B1793}, // 1e-331
-	{0xD71D6DAD34A2AF0D, 0xD953E8624B85DD78}, // 1e-330
-	{0x8672648C40E5AD68, 0x87D4713D6F33AA6B}, // 1e-329
-	{0x680EFDAF511F18C2, 0xA9C98D8CCB009506}, // 1e-328
-	{0x0212BD1B2566DEF2, 0xD43BF0EFFDC0BA48}, // 1e-327
-	{0x014BB630F7604B57, 0x84A57695FE98746D}, // 1e-326
-	{0x419EA3BD35385E2D, 0xA5CED43B7E3E9188}, // 1e-325
-	{0x52064CAC828675B9, 0xCF42894A5DCE35EA}, // 1e-324
-	{0x7343EFEBD1940993, 0x818995CE7AA0E1B2}, // 1e-323
-	{0x1014EBE6C5F90BF8, 0xA1EBFB4219491A1F}, // 1e-322
-	{0xD41A26E077774EF6, 0xCA66FA129F9B60A6}, // 1e-321
-	{0x8920B098955522B4, 0xFD00B897478238D0}, // 1e-320
-	{0x55B46E5F5D5535B0, 0x9E20735E8CB16382}, // 1e-319
-	{0xEB2189F734AA831D, 0xC5A890362FDDBC62}, // 1e-318
-	{0xA5E9EC7501D523E4, 0xF712B443BBD52B7B}, // 1e-317
-	{0x47B233C92125366E, 0x9A6BB0AA55653B2D}, // 1e-316
-	{0x999EC0BB696E840A, 0xC1069CD4EABE89F8}, // 1e-315
-	{0xC00670EA43CA250D, 0xF148440A256E2C76}, // 1e-314
-	{0x380406926A5E5728, 0x96CD2A865764DBCA}, // 1e-313
-	{0xC605083704F5ECF2, 0xBC807527ED3E12BC}, // 1e-312
-	{0xF7864A44C633682E, 0xEBA09271E88D976B}, // 1e-311
-	{0x7AB3EE6AFBE0211D, 0x93445B8731587EA3}, // 1e-310
-	{0x5960EA05BAD82964, 0xB8157268FDAE9E4C}, // 1e-309
-	{0x6FB92487298E33BD, 0xE61ACF033D1A45DF}, // 1e-308
-	{0xA5D3B6D479F8E056, 0x8FD0C16206306BAB}, // 1e-307
-	{0x8F48A4899877186C, 0xB3C4F1BA87BC8696}, // 1e-306
-	{0x331ACDABFE94DE87, 0xE0B62E2929ABA83C}, // 1e-305
-	{0x9FF0C08B7F1D0B14, 0x8C71DCD9BA0B4925}, // 1e-304
-	{0x07ECF0AE5EE44DD9, 0xAF8E5410288E1B6F}, // 1e-303
-	{0xC9E82CD9F69D6150, 0xDB71E91432B1A24A}, // 1e-302
-	{0xBE311C083A225CD2, 0x892731AC9FAF056E}, // 1e-301
-	{0x6DBD630A48AAF406, 0xAB70FE17C79AC6CA}, // 1e-300
-	{0x092CBBCCDAD5B108, 0xD64D3D9DB981787D}, // 1e-299
-	{0x25BBF56008C58EA5, 0x85F0468293F0EB4E}, // 1e-298
-	{0xAF2AF2B80AF6F24E, 0xA76C582338ED2621}, // 1e-297
-	{0x1AF5AF660DB4AEE1, 0xD1476E2C07286FAA}, // 1e-296
-	{0x50D98D9FC890ED4D, 0x82CCA4DB847945CA}, // 1e-295
-	{0xE50FF107BAB528A0, 0xA37FCE126597973C}, // 1e-294
-	{0x1E53ED49A96272C8, 0xCC5FC196FEFD7D0C}, // 1e-293
-	{0x25E8E89C13BB0F7A, 0xFF77B1FCBEBCDC4F}, // 1e-292
-	{0x77B191618C54E9AC, 0x9FAACF3DF73609B1}, // 1e-291
-	{0xD59DF5B9EF6A2417, 0xC795830D75038C1D}, // 1e-290
-	{0x4B0573286B44AD1D, 0xF97AE3D0D2446F25}, // 1e-289
-	{0x4EE367F9430AEC32, 0x9BECCE62836AC577}, // 1e-288
-	{0x229C41F793CDA73F, 0xC2E801FB244576D5}, // 1e-287
-	{0x6B43527578C1110F, 0xF3A20279ED56D48A}, // 1e-286
-	{0x830A13896B78AAA9, 0x9845418C345644D6}, // 1e-285
-	{0x23CC986BC656D553, 0xBE5691EF416BD60C}, // 1e-284
-	{0x2CBFBE86B7EC8AA8, 0xEDEC366B11C6CB8F}, // 1e-283
-	{0x7BF7D71432F3D6A9, 0x94B3A202EB1C3F39}, // 1e-282
-	{0xDAF5CCD93FB0CC53, 0xB9E08A83A5E34F07}, // 1e-281
-	{0xD1B3400F8F9CFF68, 0xE858AD248F5C22C9}, // 1e-280
-	{0x23100809B9C21FA1, 0x91376C36D99995BE}, // 1e-279
-	{0xABD40A0C2832A78A, 0xB58547448FFFFB2D}, // 1e-278
-	{0x16C90C8F323F516C, 0xE2E69915B3FFF9F9}, // 1e-277
-	{0xAE3DA7D97F6792E3, 0x8DD01FAD907FFC3B}, // 1e-276
-	{0x99CD11CFDF41779C, 0xB1442798F49FFB4A}, // 1e-275
-	{0x40405643D711D583, 0xDD95317F31C7FA1D}, // 1e-274
-	{0x482835EA666B2572, 0x8A7D3EEF7F1CFC52}, // 1e-273
-	{0xDA3243650005EECF, 0xAD1C8EAB5EE43B66}, // 1e-272
-	{0x90BED43E40076A82, 0xD863B256369D4A40}, // 1e-271
-	{0x5A7744A6E804A291, 0x873E4F75E2224E68}, // 1e-270
-	{0x711515D0A205CB36, 0xA90DE3535AAAE202}, // 1e-269
-	{0x0D5A5B44CA873E03, 0xD3515C2831559A83}, // 1e-268
-	{0xE858790AFE9486C2, 0x8412D9991ED58091}, // 1e-267
-	{0x626E974DBE39A872, 0xA5178FFF668AE0B6}, // 1e-266
-	{0xFB0A3D212DC8128F, 0xCE5D73FF402D98E3}, // 1e-265
-	{0x7CE66634BC9D0B99, 0x80FA687F881C7F8E}, // 1e-264
-	{0x1C1FFFC1EBC44E80, 0xA139029F6A239F72}, // 1e-263
-	{0xA327FFB266B56220, 0xC987434744AC874E}, // 1e-262
-	{0x4BF1FF9F0062BAA8, 0xFBE9141915D7A922}, // 1e-261
-	{0x6F773FC3603DB4A9, 0x9D71AC8FADA6C9B5}, // 1e-260
-	{0xCB550FB4384D21D3, 0xC4CE17B399107C22}, // 1e-259
-	{0x7E2A53A146606A48, 0xF6019DA07F549B2B}, // 1e-258
-	{0x2EDA7444CBFC426D, 0x99C102844F94E0FB}, // 1e-257
-	{0xFA911155FEFB5308, 0xC0314325637A1939}, // 1e-256
-	{0x793555AB7EBA27CA, 0xF03D93EEBC589F88}, // 1e-255
-	{0x4BC1558B2F3458DE, 0x96267C7535B763B5}, // 1e-254
-	{0x9EB1AAEDFB016F16, 0xBBB01B9283253CA2}, // 1e-253
-	{0x465E15A979C1CADC, 0xEA9C227723EE8BCB}, // 1e-252
-	{0x0BFACD89EC191EC9, 0x92A1958A7675175F}, // 1e-251
-	{0xCEF980EC671F667B, 0xB749FAED14125D36}, // 1e-250
-	{0x82B7E12780E7401A, 0xE51C79A85916F484}, // 1e-249
-	{0xD1B2ECB8B0908810, 0x8F31CC0937AE58D2}, // 1e-248
-	{0x861FA7E6DCB4AA15, 0xB2FE3F0B8599EF07}, // 1e-247
-	{0x67A791E093E1D49A, 0xDFBDCECE67006AC9}, // 1e-246
-	{0xE0C8BB2C5C6D24E0, 0x8BD6A141006042BD}, // 1e-245
-	{0x58FAE9F773886E18, 0xAECC49914078536D}, // 1e-244
-	{0xAF39A475506A899E, 0xDA7F5BF590966848}, // 1e-243
-	{0x6D8406C952429603, 0x888F99797A5E012D}, // 1e-242
-	{0xC8E5087BA6D33B83, 0xAAB37FD7D8F58178}, // 1e-241
-	{0xFB1E4A9A90880A64, 0xD5605FCDCF32E1D6}, // 1e-240
-	{0x5CF2EEA09A55067F, 0x855C3BE0A17FCD26}, // 1e-239
-	{0xF42FAA48C0EA481E, 0xA6B34AD8C9DFC06F}, // 1e-238
-	{0xF13B94DAF124DA26, 0xD0601D8EFC57B08B}, // 1e-237
-	{0x76C53D08D6B70858, 0x823C12795DB6CE57}, // 1e-236
-	{0x54768C4B0C64CA6E, 0xA2CB1717B52481ED}, // 1e-235
-	{0xA9942F5DCF7DFD09, 0xCB7DDCDDA26DA268}, // 1e-234
-	{0xD3F93B35435D7C4C, 0xFE5D54150B090B02}, // 1e-233
-	{0xC47BC5014A1A6DAF, 0x9EFA548D26E5A6E1}, // 1e-232
-	{0x359AB6419CA1091B, 0xC6B8E9B0709F109A}, // 1e-231
-	{0xC30163D203C94B62, 0xF867241C8CC6D4C0}, // 1e-230
-	{0x79E0DE63425DCF1D, 0x9B407691D7FC44F8}, // 1e-229
-	{0x985915FC12F542E4, 0xC21094364DFB5636}, // 1e-228
-	{0x3E6F5B7B17B2939D, 0xF294B943E17A2BC4}, // 1e-227
-	{0xA705992CEECF9C42, 0x979CF3CA6CEC5B5A}, // 1e-226
-	{0x50C6FF782A838353, 0xBD8430BD08277231}, // 1e-225
-	{0xA4F8BF5635246428, 0xECE53CEC4A314EBD}, // 1e-224
-	{0x871B7795E136BE99, 0x940F4613AE5ED136}, // 1e-223
-	{0x28E2557B59846E3F, 0xB913179899F68584}, // 1e-222
-	{0x331AEADA2FE589CF, 0xE757DD7EC07426E5}, // 1e-221
-	{0x3FF0D2C85DEF7621, 0x9096EA6F3848984F}, // 1e-220
-	{0x0FED077A756B53A9, 0xB4BCA50B065ABE63}, // 1e-219
-	{0xD3E8495912C62894, 0xE1EBCE4DC7F16DFB}, // 1e-218
-	{0x64712DD7ABBBD95C, 0x8D3360F09CF6E4BD}, // 1e-217
-	{0xBD8D794D96AACFB3, 0xB080392CC4349DEC}, // 1e-216
-	{0xECF0D7A0FC5583A0, 0xDCA04777F541C567}, // 1e-215
-	{0xF41686C49DB57244, 0x89E42CAAF9491B60}, // 1e-214
-	{0x311C2875C522CED5, 0xAC5D37D5B79B6239}, // 1e-213
-	{0x7D633293366B828B, 0xD77485CB25823AC7}, // 1e-212
-	{0xAE5DFF9C02033197, 0x86A8D39EF77164BC}, // 1e-211
-	{0xD9F57F830283FDFC, 0xA8530886B54DBDEB}, // 1e-210
-	{0xD072DF63C324FD7B, 0xD267CAA862A12D66}, // 1e-209
-	{0x4247CB9E59F71E6D, 0x8380DEA93DA4BC60}, // 1e-208
-	{0x52D9BE85F074E608, 0xA46116538D0DEB78}, // 1e-207
-	{0x67902E276C921F8B, 0xCD795BE870516656}, // 1e-206
-	{0x00BA1CD8A3DB53B6, 0x806BD9714632DFF6}, // 1e-205
-	{0x80E8A40ECCD228A4, 0xA086CFCD97BF97F3}, // 1e-204
-	{0x6122CD128006B2CD, 0xC8A883C0FDAF7DF0}, // 1e-203
-	{0x796B805720085F81, 0xFAD2A4B13D1B5D6C}, // 1e-202
-	{0xCBE3303674053BB0, 0x9CC3A6EEC6311A63}, // 1e-201
-	{0xBEDBFC4411068A9C, 0xC3F490AA77BD60FC}, // 1e-200
-	{0xEE92FB5515482D44, 0xF4F1B4D515ACB93B}, // 1e-199
-	{0x751BDD152D4D1C4A, 0x991711052D8BF3C5}, // 1e-198
-	{0xD262D45A78A0635D, 0xBF5CD54678EEF0B6}, // 1e-197
-	{0x86FB897116C87C34, 0xEF340A98172AACE4}, // 1e-196
-	{0xD45D35E6AE3D4DA0, 0x9580869F0E7AAC0E}, // 1e-195
-	{0x8974836059CCA109, 0xBAE0A846D2195712}, // 1e-194
-	{0x2BD1A438703FC94B, 0xE998D258869FACD7}, // 1e-193
-	{0x7B6306A34627DDCF, 0x91FF83775423CC06}, // 1e-192
-	{0x1A3BC84C17B1D542, 0xB67F6455292CBF08}, // 1e-191
-	{0x20CABA5F1D9E4A93, 0xE41F3D6A7377EECA}, // 1e-190
-	{0x547EB47B7282EE9C, 0x8E938662882AF53E}, // 1e-189
-	{0xE99E619A4F23AA43, 0xB23867FB2A35B28D}, // 1e-188
-	{0x6405FA00E2EC94D4, 0xDEC681F9F4C31F31}, // 1e-187
-	{0xDE83BC408DD3DD04, 0x8B3C113C38F9F37E}, // 1e-186
-	{0x9624AB50B148D445, 0xAE0B158B4738705E}, // 1e-185
-	{0x3BADD624DD9B0957, 0xD98DDAEE19068C76}, // 1e-184
-	{0xE54CA5D70A80E5D6, 0x87F8A8D4CFA417C9}, // 1e-183
-	{0x5E9FCF4CCD211F4C, 0xA9F6D30A038D1DBC}, // 1e-182
-	{0x7647C3200069671F, 0xD47487CC8470652B}, // 1e-181
-	{0x29ECD9F40041E073, 0x84C8D4DFD2C63F3B}, // 1e-180
-	{0xF468107100525890, 0xA5FB0A17C777CF09}, // 1e-179
-	{0x7182148D4066EEB4, 0xCF79CC9DB955C2CC}, // 1e-178
-	{0xC6F14CD848405530, 0x81AC1FE293D599BF}, // 1e-177
-	{0xB8ADA00E5A506A7C, 0xA21727DB38CB002F}, // 1e-176
-	{0xA6D90811F0E4851C, 0xCA9CF1D206FDC03B}, // 1e-175
-	{0x908F4A166D1DA663, 0xFD442E4688BD304A}, // 1e-174
-	{0x9A598E4E043287FE, 0x9E4A9CEC15763E2E}, // 1e-173
-	{0x40EFF1E1853F29FD, 0xC5DD44271AD3CDBA}, // 1e-172
-	{0xD12BEE59E68EF47C, 0xF7549530E188C128}, // 1e-171
-	{0x82BB74F8301958CE, 0x9A94DD3E8CF578B9}, // 1e-170
-	{0xE36A52363C1FAF01, 0xC13A148E3032D6E7}, // 1e-169
-	{0xDC44E6C3CB279AC1, 0xF18899B1BC3F8CA1}, // 1e-168
-	{0x29AB103A5EF8C0B9, 0x96F5600F15A7B7E5}, // 1e-167
-	{0x7415D448F6B6F0E7, 0xBCB2B812DB11A5DE}, // 1e-166
-	{0x111B495B3464AD21, 0xEBDF661791D60F56}, // 1e-165
-	{0xCAB10DD900BEEC34, 0x936B9FCEBB25C995}, // 1e-164
-	{0x3D5D514F40EEA742, 0xB84687C269EF3BFB}, // 1e-163
-	{0x0CB4A5A3112A5112, 0xE65829B3046B0AFA}, // 1e-162
-	{0x47F0E785EABA72AB, 0x8FF71A0FE2C2E6DC}, // 1e-161
-	{0x59ED216765690F56, 0xB3F4E093DB73A093}, // 1e-160
-	{0x306869C13EC3532C, 0xE0F218B8D25088B8}, // 1e-159
-	{0x1E414218C73A13FB, 0x8C974F7383725573}, // 1e-158
-	{0xE5D1929EF90898FA, 0xAFBD2350644EEACF}, // 1e-157
-	{0xDF45F746B74ABF39, 0xDBAC6C247D62A583}, // 1e-156
-	{0x6B8BBA8C328EB783, 0x894BC396CE5DA772}, // 1e-155
-	{0x066EA92F3F326564, 0xAB9EB47C81F5114F}, // 1e-154
-	{0xC80A537B0EFEFEBD, 0xD686619BA27255A2}, // 1e-153
-	{0xBD06742CE95F5F36, 0x8613FD0145877585}, // 1e-152
-	{0x2C48113823B73704, 0xA798FC4196E952E7}, // 1e-151
-	{0xF75A15862CA504C5, 0xD17F3B51FCA3A7A0}, // 1e-150
-	{0x9A984D73DBE722FB, 0x82EF85133DE648C4}, // 1e-149
-	{0xC13E60D0D2E0EBBA, 0xA3AB66580D5FDAF5}, // 1e-148
-	{0x318DF905079926A8, 0xCC963FEE10B7D1B3}, // 1e-147
-	{0xFDF17746497F7052, 0xFFBBCFE994E5C61F}, // 1e-146
-	{0xFEB6EA8BEDEFA633, 0x9FD561F1FD0F9BD3}, // 1e-145
-	{0xFE64A52EE96B8FC0, 0xC7CABA6E7C5382C8}, // 1e-144
-	{0x3DFDCE7AA3C673B0, 0xF9BD690A1B68637B}, // 1e-143
-	{0x06BEA10CA65C084E, 0x9C1661A651213E2D}, // 1e-142
-	{0x486E494FCFF30A62, 0xC31BFA0FE5698DB8}, // 1e-141
-	{0x5A89DBA3C3EFCCFA, 0xF3E2F893DEC3F126}, // 1e-140
-	{0xF89629465A75E01C, 0x986DDB5C6B3A76B7}, // 1e-139
-	{0xF6BBB397F1135823, 0xBE89523386091465}, // 1e-138
-	{0x746AA07DED582E2C, 0xEE2BA6C0678B597F}, // 1e-137
-	{0xA8C2A44EB4571CDC, 0x94DB483840B717EF}, // 1e-136
-	{0x92F34D62616CE413, 0xBA121A4650E4DDEB}, // 1e-135
-	{0x77B020BAF9C81D17, 0xE896A0D7E51E1566}, // 1e-134
-	{0x0ACE1474DC1D122E, 0x915E2486EF32CD60}, // 1e-133
-	{0x0D819992132456BA, 0xB5B5ADA8AAFF80B8}, // 1e-132
-	{0x10E1FFF697ED6C69, 0xE3231912D5BF60E6}, // 1e-131
-	{0xCA8D3FFA1EF463C1, 0x8DF5EFABC5979C8F}, // 1e-130
-	{0xBD308FF8A6B17CB2, 0xB1736B96B6FD83B3}, // 1e-129
-	{0xAC7CB3F6D05DDBDE, 0xDDD0467C64BCE4A0}, // 1e-128
-	{0x6BCDF07A423AA96B, 0x8AA22C0DBEF60EE4}, // 1e-127
-	{0x86C16C98D2C953C6, 0xAD4AB7112EB3929D}, // 1e-126
-	{0xE871C7BF077BA8B7, 0xD89D64D57A607744}, // 1e-125
-	{0x11471CD764AD4972, 0x87625F056C7C4A8B}, // 1e-124
-	{0xD598E40D3DD89BCF, 0xA93AF6C6C79B5D2D}, // 1e-123
-	{0x4AFF1D108D4EC2C3, 0xD389B47879823479}, // 1e-122
-	{0xCEDF722A585139BA, 0x843610CB4BF160CB}, // 1e-121
-	{0xC2974EB4EE658828, 0xA54394FE1EEDB8FE}, // 1e-120
-	{0x733D226229FEEA32, 0xCE947A3DA6A9273E}, // 1e-119
-	{0x0806357D5A3F525F, 0x811CCC668829B887}, // 1e-118
-	{0xCA07C2DCB0CF26F7, 0xA163FF802A3426A8}, // 1e-117
-	{0xFC89B393DD02F0B5, 0xC9BCFF6034C13052}, // 1e-116
-	{0xBBAC2078D443ACE2, 0xFC2C3F3841F17C67}, // 1e-115
-	{0xD54B944B84AA4C0D, 0x9D9BA7832936EDC0}, // 1e-114
-	{0x0A9E795E65D4DF11, 0xC5029163F384A931}, // 1e-113
-	{0x4D4617B5FF4A16D5, 0xF64335BCF065D37D}, // 1e-112
-	{0x504BCED1BF8E4E45, 0x99EA0196163FA42E}, // 1e-111
-	{0xE45EC2862F71E1D6, 0xC06481FB9BCF8D39}, // 1e-110
-	{0x5D767327BB4E5A4C, 0xF07DA27A82C37088}, // 1e-109
-	{0x3A6A07F8D510F86F, 0x964E858C91BA2655}, // 1e-108
-	{0x890489F70A55368B, 0xBBE226EFB628AFEA}, // 1e-107
-	{0x2B45AC74CCEA842E, 0xEADAB0ABA3B2DBE5}, // 1e-106
-	{0x3B0B8BC90012929D, 0x92C8AE6B464FC96F}, // 1e-105
-	{0x09CE6EBB40173744, 0xB77ADA0617E3BBCB}, // 1e-104
-	{0xCC420A6A101D0515, 0xE55990879DDCAABD}, // 1e-103
-	{0x9FA946824A12232D, 0x8F57FA54C2A9EAB6}, // 1e-102
-	{0x47939822DC96ABF9, 0xB32DF8E9F3546564}, // 1e-101
-	{0x59787E2B93BC56F7, 0xDFF9772470297EBD}, // 1e-100
-	{0x57EB4EDB3C55B65A, 0x8BFBEA76C619EF36}, // 1e-99
-	{0xEDE622920B6B23F1, 0xAEFAE51477A06B03}, // 1e-98
-	{0xE95FAB368E45ECED, 0xDAB99E59958885C4}, // 1e-97
-	{0x11DBCB0218EBB414, 0x88B402F7FD75539B}, // 1e-96
-	{0xD652BDC29F26A119, 0xAAE103B5FCD2A881}, // 1e-95
-	{0x4BE76D3346F0495F, 0xD59944A37C0752A2}, // 1e-94
-	{0x6F70A4400C562DDB, 0x857FCAE62D8493A5}, // 1e-93
-	{0xCB4CCD500F6BB952, 0xA6DFBD9FB8E5B88E}, // 1e-92
-	{0x7E2000A41346A7A7, 0xD097AD07A71F26B2}, // 1e-91
-	{0x8ED400668C0C28C8, 0x825ECC24C873782F}, // 1e-90
-	{0x728900802F0F32FA, 0xA2F67F2DFA90563B}, // 1e-89
-	{0x4F2B40A03AD2FFB9, 0xCBB41EF979346BCA}, // 1e-88
-	{0xE2F610C84987BFA8, 0xFEA126B7D78186BC}, // 1e-87
-	{0x0DD9CA7D2DF4D7C9, 0x9F24B832E6B0F436}, // 1e-86
-	{0x91503D1C79720DBB, 0xC6EDE63FA05D3143}, // 1e-85
-	{0x75A44C6397CE912A, 0xF8A95FCF88747D94}, // 1e-84
-	{0xC986AFBE3EE11ABA, 0x9B69DBE1B548CE7C}, // 1e-83
-	{0xFBE85BADCE996168, 0xC24452DA229B021B}, // 1e-82
-	{0xFAE27299423FB9C3, 0xF2D56790AB41C2A2}, // 1e-81
-	{0xDCCD879FC967D41A, 0x97C560BA6B0919A5}, // 1e-80
-	{0x5400E987BBC1C920, 0xBDB6B8E905CB600F}, // 1e-79
-	{0x290123E9AAB23B68, 0xED246723473E3813}, // 1e-78
-	{0xF9A0B6720AAF6521, 0x9436C0760C86E30B}, // 1e-77
-	{0xF808E40E8D5B3E69, 0xB94470938FA89BCE}, // 1e-76
-	{0xB60B1D1230B20E04, 0xE7958CB87392C2C2}, // 1e-75
-	{0xB1C6F22B5E6F48C2, 0x90BD77F3483BB9B9}, // 1e-74
-	{0x1E38AEB6360B1AF3, 0xB4ECD5F01A4AA828}, // 1e-73
-	{0x25C6DA63C38DE1B0, 0xE2280B6C20DD5232}, // 1e-72
-	{0x579C487E5A38AD0E, 0x8D590723948A535F}, // 1e-71
-	{0x2D835A9DF0C6D851, 0xB0AF48EC79ACE837}, // 1e-70
-	{0xF8E431456CF88E65, 0xDCDB1B2798182244}, // 1e-69
-	{0x1B8E9ECB641B58FF, 0x8A08F0F8BF0F156B}, // 1e-68
-	{0xE272467E3D222F3F, 0xAC8B2D36EED2DAC5}, // 1e-67
-	{0x5B0ED81DCC6ABB0F, 0xD7ADF884AA879177}, // 1e-66
-	{0x98E947129FC2B4E9, 0x86CCBB52EA94BAEA}, // 1e-65
-	{0x3F2398D747B36224, 0xA87FEA27A539E9A5}, // 1e-64
-	{0x8EEC7F0D19A03AAD, 0xD29FE4B18E88640E}, // 1e-63
-	{0x1953CF68300424AC, 0x83A3EEEEF9153E89}, // 1e-62
-	{0x5FA8C3423C052DD7, 0xA48CEAAAB75A8E2B}, // 1e-61
-	{0x3792F412CB06794D, 0xCDB02555653131B6}, // 1e-60
-	{0xE2BBD88BBEE40BD0, 0x808E17555F3EBF11}, // 1e-59
-	{0x5B6ACEAEAE9D0EC4, 0xA0B19D2AB70E6ED6}, // 1e-58
-	{0xF245825A5A445275, 0xC8DE047564D20A8B}, // 1e-57
-	{0xEED6E2F0F0D56712, 0xFB158592BE068D2E}, // 1e-56
-	{0x55464DD69685606B, 0x9CED737BB6C4183D}, // 1e-55
-	{0xAA97E14C3C26B886, 0xC428D05AA4751E4C}, // 1e-54
-	{0xD53DD99F4B3066A8, 0xF53304714D9265DF}, // 1e-53
-	{0xE546A8038EFE4029, 0x993FE2C6D07B7FAB}, // 1e-52
-	{0xDE98520472BDD033, 0xBF8FDB78849A5F96}, // 1e-51
-	{0x963E66858F6D4440, 0xEF73D256A5C0F77C}, // 1e-50
-	{0xDDE7001379A44AA8, 0x95A8637627989AAD}, // 1e-49
-	{0x5560C018580D5D52, 0xBB127C53B17EC159}, // 1e-48
-	{0xAAB8F01E6E10B4A6, 0xE9D71B689DDE71AF}, // 1e-47
-	{0xCAB3961304CA70E8, 0x9226712162AB070D}, // 1e-46
-	{0x3D607B97C5FD0D22, 0xB6B00D69BB55C8D1}, // 1e-45
-	{0x8CB89A7DB77C506A, 0xE45C10C42A2B3B05}, // 1e-44
-	{0x77F3608E92ADB242, 0x8EB98A7A9A5B04E3}, // 1e-43
-	{0x55F038B237591ED3, 0xB267ED1940F1C61C}, // 1e-42
-	{0x6B6C46DEC52F6688, 0xDF01E85F912E37A3}, // 1e-41
-	{0x2323AC4B3B3DA015, 0x8B61313BBABCE2C6}, // 1e-40
-	{0xABEC975E0A0D081A, 0xAE397D8AA96C1B77}, // 1e-39
-	{0x96E7BD358C904A21, 0xD9C7DCED53C72255}, // 1e-38
-	{0x7E50D64177DA2E54, 0x881CEA14545C7575}, // 1e-37
-	{0xDDE50BD1D5D0B9E9, 0xAA242499697392D2}, // 1e-36
-	{0x955E4EC64B44E864, 0xD4AD2DBFC3D07787}, // 1e-35
-	{0xBD5AF13BEF0B113E, 0x84EC3C97DA624AB4}, // 1e-34
-	{0xECB1AD8AEACDD58E, 0xA6274BBDD0FADD61}, // 1e-33
-	{0x67DE18EDA5814AF2, 0xCFB11EAD453994BA}, // 1e-32
-	{0x80EACF948770CED7, 0x81CEB32C4B43FCF4}, // 1e-31
-	{0xA1258379A94D028D, 0xA2425FF75E14FC31}, // 1e-30
-	{0x096EE45813A04330, 0xCAD2F7F5359A3B3E}, // 1e-29
-	{0x8BCA9D6E188853FC, 0xFD87B5F28300CA0D}, // 1e-28
-	{0x775EA264CF55347D, 0x9E74D1B791E07E48}, // 1e-27
-	{0x95364AFE032A819D, 0xC612062576589DDA}, // 1e-26
-	{0x3A83DDBD83F52204, 0xF79687AED3EEC551}, // 1e-25
-	{0xC4926A9672793542, 0x9ABE14CD44753B52}, // 1e-24
-	{0x75B7053C0F178293, 0xC16D9A0095928A27}, // 1e-23
-	{0x5324C68B12DD6338, 0xF1C90080BAF72CB1}, // 1e-22
-	{0xD3F6FC16EBCA5E03, 0x971DA05074DA7BEE}, // 1e-21
-	{0x88F4BB1CA6BCF584, 0xBCE5086492111AEA}, // 1e-20
-	{0x2B31E9E3D06C32E5, 0xEC1E4A7DB69561A5}, // 1e-19
-	{0x3AFF322E62439FCF, 0x9392EE8E921D5D07}, // 1e-18
-	{0x09BEFEB9FAD487C2, 0xB877AA3236A4B449}, // 1e-17
-	{0x4C2EBE687989A9B3, 0xE69594BEC44DE15B}, // 1e-16
-	{0x0F9D37014BF60A10, 0x901D7CF73AB0ACD9}, // 1e-15
-	{0x538484C19EF38C94, 0xB424DC35095CD80F}, // 1e-14
-	{0x2865A5F206B06FB9, 0xE12E13424BB40E13}, // 1e-13
-	{0xF93F87B7442E45D3, 0x8CBCCC096F5088CB}, // 1e-12
-	{0xF78F69A51539D748, 0xAFEBFF0BCB24AAFE}, // 1e-11
-	{0xB573440E5A884D1B, 0xDBE6FECEBDEDD5BE}, // 1e-10
-	{0x31680A88F8953030, 0x89705F4136B4A597}, // 1e-9
-	{0xFDC20D2B36BA7C3D, 0xABCC77118461CEFC}, // 1e-8
-	{0x3D32907604691B4C, 0xD6BF94D5E57A42BC}, // 1e-7
-	{0xA63F9A49C2C1B10F, 0x8637BD05AF6C69B5}, // 1e-6
-	{0x0FCF80DC33721D53, 0xA7C5AC471B478423}, // 1e-5
-	{0xD3C36113404EA4A8, 0xD1B71758E219652B}, // 1e-4
-	{0x645A1CAC083126E9, 0x83126E978D4FDF3B}, // 1e-3
-	{0x3D70A3D70A3D70A3, 0xA3D70A3D70A3D70A}, // 1e-2
-	{0xCCCCCCCCCCCCCCCC, 0xCCCCCCCCCCCCCCCC}, // 1e-1
-	{0x0000000000000000, 0x8000000000000000}, // 1e0
-	{0x0000000000000000, 0xA000000000000000}, // 1e1
-	{0x0000000000000000, 0xC800000000000000}, // 1e2
-	{0x0000000000000000, 0xFA00000000000000}, // 1e3
-	{0x0000000000000000, 0x9C40000000000000}, // 1e4
-	{0x0000000000000000, 0xC350000000000000}, // 1e5
-	{0x0000000000000000, 0xF424000000000000}, // 1e6
-	{0x0000000000000000, 0x9896800000000000}, // 1e7
-	{0x0000000000000000, 0xBEBC200000000000}, // 1e8
-	{0x0000000000000000, 0xEE6B280000000000}, // 1e9
-	{0x0000000000000000, 0x9502F90000000000}, // 1e10
-	{0x0000000000000000, 0xBA43B74000000000}, // 1e11
-	{0x0000000000000000, 0xE8D4A51000000000}, // 1e12
-	{0x0000000000000000, 0x9184E72A00000000}, // 1e13
-	{0x0000000000000000, 0xB5E620F480000000}, // 1e14
-	{0x0000000000000000, 0xE35FA931A0000000}, // 1e15
-	{0x0000000000000000, 0x8E1BC9BF04000000}, // 1e16
-	{0x0000000000000000, 0xB1A2BC2EC5000000}, // 1e17
-	{0x0000000000000000, 0xDE0B6B3A76400000}, // 1e18
-	{0x0000000000000000, 0x8AC7230489E80000}, // 1e19
-	{0x0000000000000000, 0xAD78EBC5AC620000}, // 1e20
-	{0x0000000000000000, 0xD8D726B7177A8000}, // 1e21
-	{0x0000000000000000, 0x878678326EAC9000}, // 1e22
-	{0x0000000000000000, 0xA968163F0A57B400}, // 1e23
-	{0x0000000000000000, 0xD3C21BCECCEDA100}, // 1e24
-	{0x0000000000000000, 0x84595161401484A0}, // 1e25
-	{0x0000000000000000, 0xA56FA5B99019A5C8}, // 1e26
-	{0x0000000000000000, 0xCECB8F27F4200F3A}, // 1e27
-	{0x4000000000000000, 0x813F3978F8940984}, // 1e28
-	{0x5000000000000000, 0xA18F07D736B90BE5}, // 1e29
-	{0xA400000000000000, 0xC9F2C9CD04674EDE}, // 1e30
-	{0x4D00000000000000, 0xFC6F7C4045812296}, // 1e31
-	{0xF020000000000000, 0x9DC5ADA82B70B59D}, // 1e32
-	{0x6C28000000000000, 0xC5371912364CE305}, // 1e33
-	{0xC732000000000000, 0xF684DF56C3E01BC6}, // 1e34
-	{0x3C7F400000000000, 0x9A130B963A6C115C}, // 1e35
-	{0x4B9F100000000000, 0xC097CE7BC90715B3}, // 1e36
-	{0x1E86D40000000000, 0xF0BDC21ABB48DB20}, // 1e37
-	{0x1314448000000000, 0x96769950B50D88F4}, // 1e38
-	{0x17D955A000000000, 0xBC143FA4E250EB31}, // 1e39
-	{0x5DCFAB0800000000, 0xEB194F8E1AE525FD}, // 1e40
-	{0x5AA1CAE500000000, 0x92EFD1B8D0CF37BE}, // 1e41
-	{0xF14A3D9E40000000, 0xB7ABC627050305AD}, // 1e42
-	{0x6D9CCD05D0000000, 0xE596B7B0C643C719}, // 1e43
-	{0xE4820023A2000000, 0x8F7E32CE7BEA5C6F}, // 1e44
-	{0xDDA2802C8A800000, 0xB35DBF821AE4F38B}, // 1e45
-	{0xD50B2037AD200000, 0xE0352F62A19E306E}, // 1e46
-	{0x4526F422CC340000, 0x8C213D9DA502DE45}, // 1e47
-	{0x9670B12B7F410000, 0xAF298D050E4395D6}, // 1e48
-	{0x3C0CDD765F114000, 0xDAF3F04651D47B4C}, // 1e49
-	{0xA5880A69FB6AC800, 0x88D8762BF324CD0F}, // 1e50
-	{0x8EEA0D047A457A00, 0xAB0E93B6EFEE0053}, // 1e51
-	{0x72A4904598D6D880, 0xD5D238A4ABE98068}, // 1e52
-	{0x47A6DA2B7F864750, 0x85A36366EB71F041}, // 1e53
-	{0x999090B65F67D924, 0xA70C3C40A64E6C51}, // 1e54
-	{0xFFF4B4E3F741CF6D, 0xD0CF4B50CFE20765}, // 1e55
-	{0xBFF8F10E7A8921A4, 0x82818F1281ED449F}, // 1e56
-	{0xAFF72D52192B6A0D, 0xA321F2D7226895C7}, // 1e57
-	{0x9BF4F8A69F764490, 0xCBEA6F8CEB02BB39}, // 1e58
-	{0x02F236D04753D5B4, 0xFEE50B7025C36A08}, // 1e59
-	{0x01D762422C946590, 0x9F4F2726179A2245}, // 1e60
-	{0x424D3AD2B7B97EF5, 0xC722F0EF9D80AAD6}, // 1e61
-	{0xD2E0898765A7DEB2, 0xF8EBAD2B84E0D58B}, // 1e62
-	{0x63CC55F49F88EB2F, 0x9B934C3B330C8577}, // 1e63
-	{0x3CBF6B71C76B25FB, 0xC2781F49FFCFA6D5}, // 1e64
-	{0x8BEF464E3945EF7A, 0xF316271C7FC3908A}, // 1e65
-	{0x97758BF0E3CBB5AC, 0x97EDD871CFDA3A56}, // 1e66
-	{0x3D52EEED1CBEA317, 0xBDE94E8E43D0C8EC}, // 1e67
-	{0x4CA7AAA863EE4BDD, 0xED63A231D4C4FB27}, // 1e68
-	{0x8FE8CAA93E74EF6A, 0x945E455F24FB1CF8}, // 1e69
-	{0xB3E2FD538E122B44, 0xB975D6B6EE39E436}, // 1e70
-	{0x60DBBCA87196B616, 0xE7D34C64A9C85D44}, // 1e71
-	{0xBC8955E946FE31CD, 0x90E40FBEEA1D3A4A}, // 1e72
-	{0x6BABAB6398BDBE41, 0xB51D13AEA4A488DD}, // 1e73
-	{0xC696963C7EED2DD1, 0xE264589A4DCDAB14}, // 1e74
-	{0xFC1E1DE5CF543CA2, 0x8D7EB76070A08AEC}, // 1e75
-	{0x3B25A55F43294BCB, 0xB0DE65388CC8ADA8}, // 1e76
-	{0x49EF0EB713F39EBE, 0xDD15FE86AFFAD912}, // 1e77
-	{0x6E3569326C784337, 0x8A2DBF142DFCC7AB}, // 1e78
-	{0x49C2C37F07965404, 0xACB92ED9397BF996}, // 1e79
-	{0xDC33745EC97BE906, 0xD7E77A8F87DAF7FB}, // 1e80
-	{0x69A028BB3DED71A3, 0x86F0AC99B4E8DAFD}, // 1e81
-	{0xC40832EA0D68CE0C, 0xA8ACD7C0222311BC}, // 1e82
-	{0xF50A3FA490C30190, 0xD2D80DB02AABD62B}, // 1e83
-	{0x792667C6DA79E0FA, 0x83C7088E1AAB65DB}, // 1e84
-	{0x577001B891185938, 0xA4B8CAB1A1563F52}, // 1e85
-	{0xED4C0226B55E6F86, 0xCDE6FD5E09ABCF26}, // 1e86
-	{0x544F8158315B05B4, 0x80B05E5AC60B6178}, // 1e87
-	{0x696361AE3DB1C721, 0xA0DC75F1778E39D6}, // 1e88
-	{0x03BC3A19CD1E38E9, 0xC913936DD571C84C}, // 1e89
-	{0x04AB48A04065C723, 0xFB5878494ACE3A5F}, // 1e90
-	{0x62EB0D64283F9C76, 0x9D174B2DCEC0E47B}, // 1e91
-	{0x3BA5D0BD324F8394, 0xC45D1DF942711D9A}, // 1e92
-	{0xCA8F44EC7EE36479, 0xF5746577930D6500}, // 1e93
-	{0x7E998B13CF4E1ECB, 0x9968BF6ABBE85F20}, // 1e94
-	{0x9E3FEDD8C321A67E, 0xBFC2EF456AE276E8}, // 1e95
-	{0xC5CFE94EF3EA101E, 0xEFB3AB16C59B14A2}, // 1e96
-	{0xBBA1F1D158724A12, 0x95D04AEE3B80ECE5}, // 1e97
-	{0x2A8A6E45AE8EDC97, 0xBB445DA9CA61281F}, // 1e98
-	{0xF52D09D71A3293BD, 0xEA1575143CF97226}, // 1e99
-	{0x593C2626705F9C56, 0x924D692CA61BE758}, // 1e100
-	{0x6F8B2FB00C77836C, 0xB6E0C377CFA2E12E}, // 1e101
-	{0x0B6DFB9C0F956447, 0xE498F455C38B997A}, // 1e102
-	{0x4724BD4189BD5EAC, 0x8EDF98B59A373FEC}, // 1e103
-	{0x58EDEC91EC2CB657, 0xB2977EE300C50FE7}, // 1e104
-	{0x2F2967B66737E3ED, 0xDF3D5E9BC0F653E1}, // 1e105
-	{0xBD79E0D20082EE74, 0x8B865B215899F46C}, // 1e106
-	{0xECD8590680A3AA11, 0xAE67F1E9AEC07187}, // 1e107
-	{0xE80E6F4820CC9495, 0xDA01EE641A708DE9}, // 1e108
-	{0x3109058D147FDCDD, 0x884134FE908658B2}, // 1e109
-	{0xBD4B46F0599FD415, 0xAA51823E34A7EEDE}, // 1e110
-	{0x6C9E18AC7007C91A, 0xD4E5E2CDC1D1EA96}, // 1e111
-	{0x03E2CF6BC604DDB0, 0x850FADC09923329E}, // 1e112
-	{0x84DB8346B786151C, 0xA6539930BF6BFF45}, // 1e113
-	{0xE612641865679A63, 0xCFE87F7CEF46FF16}, // 1e114
-	{0x4FCB7E8F3F60C07E, 0x81F14FAE158C5F6E}, // 1e115
-	{0xE3BE5E330F38F09D, 0xA26DA3999AEF7749}, // 1e116
-	{0x5CADF5BFD3072CC5, 0xCB090C8001AB551C}, // 1e117
-	{0x73D9732FC7C8F7F6, 0xFDCB4FA002162A63}, // 1e118
-	{0x2867E7FDDCDD9AFA, 0x9E9F11C4014DDA7E}, // 1e119
-	{0xB281E1FD541501B8, 0xC646D63501A1511D}, // 1e120
-	{0x1F225A7CA91A4226, 0xF7D88BC24209A565}, // 1e121
-	{0x3375788DE9B06958, 0x9AE757596946075F}, // 1e122
-	{0x0052D6B1641C83AE, 0xC1A12D2FC3978937}, // 1e123
-	{0xC0678C5DBD23A49A, 0xF209787BB47D6B84}, // 1e124
-	{0xF840B7BA963646E0, 0x9745EB4D50CE6332}, // 1e125
-	{0xB650E5A93BC3D898, 0xBD176620A501FBFF}, // 1e126
-	{0xA3E51F138AB4CEBE, 0xEC5D3FA8CE427AFF}, // 1e127
-	{0xC66F336C36B10137, 0x93BA47C980E98CDF}, // 1e128
-	{0xB80B0047445D4184, 0xB8A8D9BBE123F017}, // 1e129
-	{0xA60DC059157491E5, 0xE6D3102AD96CEC1D}, // 1e130
-	{0x87C89837AD68DB2F, 0x9043EA1AC7E41392}, // 1e131
-	{0x29BABE4598C311FB, 0xB454E4A179DD1877}, // 1e132
-	{0xF4296DD6FEF3D67A, 0xE16A1DC9D8545E94}, // 1e133
-	{0x1899E4A65F58660C, 0x8CE2529E2734BB1D}, // 1e134
-	{0x5EC05DCFF72E7F8F, 0xB01AE745B101E9E4}, // 1e135
-	{0x76707543F4FA1F73, 0xDC21A1171D42645D}, // 1e136
-	{0x6A06494A791C53A8, 0x899504AE72497EBA}, // 1e137
-	{0x0487DB9D17636892, 0xABFA45DA0EDBDE69}, // 1e138
-	{0x45A9D2845D3C42B6, 0xD6F8D7509292D603}, // 1e139
-	{0x0B8A2392BA45A9B2, 0x865B86925B9BC5C2}, // 1e140
-	{0x8E6CAC7768D7141E, 0xA7F26836F282B732}, // 1e141
-	{0x3207D795430CD926, 0xD1EF0244AF2364FF}, // 1e142
-	{0x7F44E6BD49E807B8, 0x8335616AED761F1F}, // 1e143
-	{0x5F16206C9C6209A6, 0xA402B9C5A8D3A6E7}, // 1e144
-	{0x36DBA887C37A8C0F, 0xCD036837130890A1}, // 1e145
-	{0xC2494954DA2C9789, 0x802221226BE55A64}, // 1e146
-	{0xF2DB9BAA10B7BD6C, 0xA02AA96B06DEB0FD}, // 1e147
-	{0x6F92829494E5ACC7, 0xC83553C5C8965D3D}, // 1e148
-	{0xCB772339BA1F17F9, 0xFA42A8B73ABBF48C}, // 1e149
-	{0xFF2A760414536EFB, 0x9C69A97284B578D7}, // 1e150
-	{0xFEF5138519684ABA, 0xC38413CF25E2D70D}, // 1e151
-	{0x7EB258665FC25D69, 0xF46518C2EF5B8CD1}, // 1e152
-	{0xEF2F773FFBD97A61, 0x98BF2F79D5993802}, // 1e153
-	{0xAAFB550FFACFD8FA, 0xBEEEFB584AFF8603}, // 1e154
-	{0x95BA2A53F983CF38, 0xEEAABA2E5DBF6784}, // 1e155
-	{0xDD945A747BF26183, 0x952AB45CFA97A0B2}, // 1e156
-	{0x94F971119AEEF9E4, 0xBA756174393D88DF}, // 1e157
-	{0x7A37CD5601AAB85D, 0xE912B9D1478CEB17}, // 1e158
-	{0xAC62E055C10AB33A, 0x91ABB422CCB812EE}, // 1e159
-	{0x577B986B314D6009, 0xB616A12B7FE617AA}, // 1e160
-	{0xED5A7E85FDA0B80B, 0xE39C49765FDF9D94}, // 1e161
-	{0x14588F13BE847307, 0x8E41ADE9FBEBC27D}, // 1e162
-	{0x596EB2D8AE258FC8, 0xB1D219647AE6B31C}, // 1e163
-	{0x6FCA5F8ED9AEF3BB, 0xDE469FBD99A05FE3}, // 1e164
-	{0x25DE7BB9480D5854, 0x8AEC23D680043BEE}, // 1e165
-	{0xAF561AA79A10AE6A, 0xADA72CCC20054AE9}, // 1e166
-	{0x1B2BA1518094DA04, 0xD910F7FF28069DA4}, // 1e167
-	{0x90FB44D2F05D0842, 0x87AA9AFF79042286}, // 1e168
-	{0x353A1607AC744A53, 0xA99541BF57452B28}, // 1e169
-	{0x42889B8997915CE8, 0xD3FA922F2D1675F2}, // 1e170
-	{0x69956135FEBADA11, 0x847C9B5D7C2E09B7}, // 1e171
-	{0x43FAB9837E699095, 0xA59BC234DB398C25}, // 1e172
-	{0x94F967E45E03F4BB, 0xCF02B2C21207EF2E}, // 1e173
-	{0x1D1BE0EEBAC278F5, 0x8161AFB94B44F57D}, // 1e174
-	{0x6462D92A69731732, 0xA1BA1BA79E1632DC}, // 1e175
-	{0x7D7B8F7503CFDCFE, 0xCA28A291859BBF93}, // 1e176
-	{0x5CDA735244C3D43E, 0xFCB2CB35E702AF78}, // 1e177
-	{0x3A0888136AFA64A7, 0x9DEFBF01B061ADAB}, // 1e178
-	{0x088AAA1845B8FDD0, 0xC56BAEC21C7A1916}, // 1e179
-	{0x8AAD549E57273D45, 0xF6C69A72A3989F5B}, // 1e180
-	{0x36AC54E2F678864B, 0x9A3C2087A63F6399}, // 1e181
-	{0x84576A1BB416A7DD, 0xC0CB28A98FCF3C7F}, // 1e182
-	{0x656D44A2A11C51D5, 0xF0FDF2D3F3C30B9F}, // 1e183
-	{0x9F644AE5A4B1B325, 0x969EB7C47859E743}, // 1e184
-	{0x873D5D9F0DDE1FEE, 0xBC4665B596706114}, // 1e185
-	{0xA90CB506D155A7EA, 0xEB57FF22FC0C7959}, // 1e186
-	{0x09A7F12442D588F2, 0x9316FF75DD87CBD8}, // 1e187
-	{0x0C11ED6D538AEB2F, 0xB7DCBF5354E9BECE}, // 1e188
-	{0x8F1668C8A86DA5FA, 0xE5D3EF282A242E81}, // 1e189
-	{0xF96E017D694487BC, 0x8FA475791A569D10}, // 1e190
-	{0x37C981DCC395A9AC, 0xB38D92D760EC4455}, // 1e191
-	{0x85BBE253F47B1417, 0xE070F78D3927556A}, // 1e192
-	{0x93956D7478CCEC8E, 0x8C469AB843B89562}, // 1e193
-	{0x387AC8D1970027B2, 0xAF58416654A6BABB}, // 1e194
-	{0x06997B05FCC0319E, 0xDB2E51BFE9D0696A}, // 1e195
-	{0x441FECE3BDF81F03, 0x88FCF317F22241E2}, // 1e196
-	{0xD527E81CAD7626C3, 0xAB3C2FDDEEAAD25A}, // 1e197
-	{0x8A71E223D8D3B074, 0xD60B3BD56A5586F1}, // 1e198
-	{0xF6872D5667844E49, 0x85C7056562757456}, // 1e199
-	{0xB428F8AC016561DB, 0xA738C6BEBB12D16C}, // 1e200
-	{0xE13336D701BEBA52, 0xD106F86E69D785C7}, // 1e201
-	{0xECC0024661173473, 0x82A45B450226B39C}, // 1e202
-	{0x27F002D7F95D0190, 0xA34D721642B06084}, // 1e203
-	{0x31EC038DF7B441F4, 0xCC20CE9BD35C78A5}, // 1e204
-	{0x7E67047175A15271, 0xFF290242C83396CE}, // 1e205
-	{0x0F0062C6E984D386, 0x9F79A169BD203E41}, // 1e206
-	{0x52C07B78A3E60868, 0xC75809C42C684DD1}, // 1e207
-	{0xA7709A56CCDF8A82, 0xF92E0C3537826145}, // 1e208
-	{0x88A66076400BB691, 0x9BBCC7A142B17CCB}, // 1e209
-	{0x6ACFF893D00EA435, 0xC2ABF989935DDBFE}, // 1e210
-	{0x0583F6B8C4124D43, 0xF356F7EBF83552FE}, // 1e211
-	{0xC3727A337A8B704A, 0x98165AF37B2153DE}, // 1e212
-	{0x744F18C0592E4C5C, 0xBE1BF1B059E9A8D6}, // 1e213
-	{0x1162DEF06F79DF73, 0xEDA2EE1C7064130C}, // 1e214
-	{0x8ADDCB5645AC2BA8, 0x9485D4D1C63E8BE7}, // 1e215
-	{0x6D953E2BD7173692, 0xB9A74A0637CE2EE1}, // 1e216
-	{0xC8FA8DB6CCDD0437, 0xE8111C87C5C1BA99}, // 1e217
-	{0x1D9C9892400A22A2, 0x910AB1D4DB9914A0}, // 1e218
-	{0x2503BEB6D00CAB4B, 0xB54D5E4A127F59C8}, // 1e219
-	{0x2E44AE64840FD61D, 0xE2A0B5DC971F303A}, // 1e220
-	{0x5CEAECFED289E5D2, 0x8DA471A9DE737E24}, // 1e221
-	{0x7425A83E872C5F47, 0xB10D8E1456105DAD}, // 1e222
-	{0xD12F124E28F77719, 0xDD50F1996B947518}, // 1e223
-	{0x82BD6B70D99AAA6F, 0x8A5296FFE33CC92F}, // 1e224
-	{0x636CC64D1001550B, 0xACE73CBFDC0BFB7B}, // 1e225
-	{0x3C47F7E05401AA4E, 0xD8210BEFD30EFA5A}, // 1e226
-	{0x65ACFAEC34810A71, 0x8714A775E3E95C78}, // 1e227
-	{0x7F1839A741A14D0D, 0xA8D9D1535CE3B396}, // 1e228
-	{0x1EDE48111209A050, 0xD31045A8341CA07C}, // 1e229
-	{0x934AED0AAB460432, 0x83EA2B892091E44D}, // 1e230
-	{0xF81DA84D5617853F, 0xA4E4B66B68B65D60}, // 1e231
-	{0x36251260AB9D668E, 0xCE1DE40642E3F4B9}, // 1e232
-	{0xC1D72B7C6B426019, 0x80D2AE83E9CE78F3}, // 1e233
-	{0xB24CF65B8612F81F, 0xA1075A24E4421730}, // 1e234
-	{0xDEE033F26797B627, 0xC94930AE1D529CFC}, // 1e235
-	{0x169840EF017DA3B1, 0xFB9B7CD9A4A7443C}, // 1e236
-	{0x8E1F289560EE864E, 0x9D412E0806E88AA5}, // 1e237
-	{0xF1A6F2BAB92A27E2, 0xC491798A08A2AD4E}, // 1e238
-	{0xAE10AF696774B1DB, 0xF5B5D7EC8ACB58A2}, // 1e239
-	{0xACCA6DA1E0A8EF29, 0x9991A6F3D6BF1765}, // 1e240
-	{0x17FD090A58D32AF3, 0xBFF610B0CC6EDD3F}, // 1e241
-	{0xDDFC4B4CEF07F5B0, 0xEFF394DCFF8A948E}, // 1e242
-	{0x4ABDAF101564F98E, 0x95F83D0A1FB69CD9}, // 1e243
-	{0x9D6D1AD41ABE37F1, 0xBB764C4CA7A4440F}, // 1e244
-	{0x84C86189216DC5ED, 0xEA53DF5FD18D5513}, // 1e245
-	{0x32FD3CF5B4E49BB4, 0x92746B9BE2F8552C}, // 1e246
-	{0x3FBC8C33221DC2A1, 0xB7118682DBB66A77}, // 1e247
-	{0x0FABAF3FEAA5334A, 0xE4D5E82392A40515}, // 1e248
-	{0x29CB4D87F2A7400E, 0x8F05B1163BA6832D}, // 1e249
-	{0x743E20E9EF511012, 0xB2C71D5BCA9023F8}, // 1e250
-	{0x914DA9246B255416, 0xDF78E4B2BD342CF6}, // 1e251
-	{0x1AD089B6C2F7548E, 0x8BAB8EEFB6409C1A}, // 1e252
-	{0xA184AC2473B529B1, 0xAE9672ABA3D0C320}, // 1e253
-	{0xC9E5D72D90A2741E, 0xDA3C0F568CC4F3E8}, // 1e254
-	{0x7E2FA67C7A658892, 0x8865899617FB1871}, // 1e255
-	{0xDDBB901B98FEEAB7, 0xAA7EEBFB9DF9DE8D}, // 1e256
-	{0x552A74227F3EA565, 0xD51EA6FA85785631}, // 1e257
-	{0xD53A88958F87275F, 0x8533285C936B35DE}, // 1e258
-	{0x8A892ABAF368F137, 0xA67FF273B8460356}, // 1e259
-	{0x2D2B7569B0432D85, 0xD01FEF10A657842C}, // 1e260
-	{0x9C3B29620E29FC73, 0x8213F56A67F6B29B}, // 1e261
-	{0x8349F3BA91B47B8F, 0xA298F2C501F45F42}, // 1e262
-	{0x241C70A936219A73, 0xCB3F2F7642717713}, // 1e263
-	{0xED238CD383AA0110, 0xFE0EFB53D30DD4D7}, // 1e264
-	{0xF4363804324A40AA, 0x9EC95D1463E8A506}, // 1e265
-	{0xB143C6053EDCD0D5, 0xC67BB4597CE2CE48}, // 1e266
-	{0xDD94B7868E94050A, 0xF81AA16FDC1B81DA}, // 1e267
-	{0xCA7CF2B4191C8326, 0x9B10A4E5E9913128}, // 1e268
-	{0xFD1C2F611F63A3F0, 0xC1D4CE1F63F57D72}, // 1e269
-	{0xBC633B39673C8CEC, 0xF24A01A73CF2DCCF}, // 1e270
-	{0xD5BE0503E085D813, 0x976E41088617CA01}, // 1e271
-	{0x4B2D8644D8A74E18, 0xBD49D14AA79DBC82}, // 1e272
-	{0xDDF8E7D60ED1219E, 0xEC9C459D51852BA2}, // 1e273
-	{0xCABB90E5C942B503, 0x93E1AB8252F33B45}, // 1e274
-	{0x3D6A751F3B936243, 0xB8DA1662E7B00A17}, // 1e275
-	{0x0CC512670A783AD4, 0xE7109BFBA19C0C9D}, // 1e276
-	{0x27FB2B80668B24C5, 0x906A617D450187E2}, // 1e277
-	{0xB1F9F660802DEDF6, 0xB484F9DC9641E9DA}, // 1e278
-	{0x5E7873F8A0396973, 0xE1A63853BBD26451}, // 1e279
-	{0xDB0B487B6423E1E8, 0x8D07E33455637EB2}, // 1e280
-	{0x91CE1A9A3D2CDA62, 0xB049DC016ABC5E5F}, // 1e281
-	{0x7641A140CC7810FB, 0xDC5C5301C56B75F7}, // 1e282
-	{0xA9E904C87FCB0A9D, 0x89B9B3E11B6329BA}, // 1e283
-	{0x546345FA9FBDCD44, 0xAC2820D9623BF429}, // 1e284
-	{0xA97C177947AD4095, 0xD732290FBACAF133}, // 1e285
-	{0x49ED8EABCCCC485D, 0x867F59A9D4BED6C0}, // 1e286
-	{0x5C68F256BFFF5A74, 0xA81F301449EE8C70}, // 1e287
-	{0x73832EEC6FFF3111, 0xD226FC195C6A2F8C}, // 1e288
-	{0xC831FD53C5FF7EAB, 0x83585D8FD9C25DB7}, // 1e289
-	{0xBA3E7CA8B77F5E55, 0xA42E74F3D032F525}, // 1e290
-	{0x28CE1BD2E55F35EB, 0xCD3A1230C43FB26F}, // 1e291
-	{0x7980D163CF5B81B3, 0x80444B5E7AA7CF85}, // 1e292
-	{0xD7E105BCC332621F, 0xA0555E361951C366}, // 1e293
-	{0x8DD9472BF3FEFAA7, 0xC86AB5C39FA63440}, // 1e294
-	{0xB14F98F6F0FEB951, 0xFA856334878FC150}, // 1e295
-	{0x6ED1BF9A569F33D3, 0x9C935E00D4B9D8D2}, // 1e296
-	{0x0A862F80EC4700C8, 0xC3B8358109E84F07}, // 1e297
-	{0xCD27BB612758C0FA, 0xF4A642E14C6262C8}, // 1e298
-	{0x8038D51CB897789C, 0x98E7E9CCCFBD7DBD}, // 1e299
-	{0xE0470A63E6BD56C3, 0xBF21E44003ACDD2C}, // 1e300
-	{0x1858CCFCE06CAC74, 0xEEEA5D5004981478}, // 1e301
-	{0x0F37801E0C43EBC8, 0x95527A5202DF0CCB}, // 1e302
-	{0xD30560258F54E6BA, 0xBAA718E68396CFFD}, // 1e303
-	{0x47C6B82EF32A2069, 0xE950DF20247C83FD}, // 1e304
-	{0x4CDC331D57FA5441, 0x91D28B7416CDD27E}, // 1e305
-	{0xE0133FE4ADF8E952, 0xB6472E511C81471D}, // 1e306
-	{0x58180FDDD97723A6, 0xE3D8F9E563A198E5}, // 1e307
-	{0x570F09EAA7EA7648, 0x8E679C2F5E44FF8F}, // 1e308
-	{0x2CD2CC6551E513DA, 0xB201833B35D63F73}, // 1e309
-	{0xF8077F7EA65E58D1, 0xDE81E40A034BCF4F}, // 1e310
-	{0xFB04AFAF27FAF782, 0x8B112E86420F6191}, // 1e311
-	{0x79C5DB9AF1F9B563, 0xADD57A27D29339F6}, // 1e312
-	{0x18375281AE7822BC, 0xD94AD8B1C7380874}, // 1e313
-	{0x8F2293910D0B15B5, 0x87CEC76F1C830548}, // 1e314
-	{0xB2EB3875504DDB22, 0xA9C2794AE3A3C69A}, // 1e315
-	{0x5FA60692A46151EB, 0xD433179D9C8CB841}, // 1e316
-	{0xDBC7C41BA6BCD333, 0x849FEEC281D7F328}, // 1e317
-	{0x12B9B522906C0800, 0xA5C7EA73224DEFF3}, // 1e318
-	{0xD768226B34870A00, 0xCF39E50FEAE16BEF}, // 1e319
-	{0xE6A1158300D46640, 0x81842F29F2CCE375}, // 1e320
-	{0x60495AE3C1097FD0, 0xA1E53AF46F801C53}, // 1e321
-	{0x385BB19CB14BDFC4, 0xCA5E89B18B602368}, // 1e322
-	{0x46729E03DD9ED7B5, 0xFCF62C1DEE382C42}, // 1e323
-	{0x6C07A2C26A8346D1, 0x9E19DB92B4E31BA9}, // 1e324
-	{0xC7098B7305241885, 0xC5A05277621BE293}, // 1e325
-	{0xB8CBEE4FC66D1EA7, 0xF70867153AA2DB38}, // 1e326
-	{0x737F74F1DC043328, 0x9A65406D44A5C903}, // 1e327
-	{0x505F522E53053FF2, 0xC0FE908895CF3B44}, // 1e328
-	{0x647726B9E7C68FEF, 0xF13E34AABB430A15}, // 1e329
-	{0x5ECA783430DC19F5, 0x96C6E0EAB509E64D}, // 1e330
-	{0xB67D16413D132072, 0xBC789925624C5FE0}, // 1e331
-	{0xE41C5BD18C57E88F, 0xEB96BF6EBADF77D8}, // 1e332
-	{0x8E91B962F7B6F159, 0x933E37A534CBAAE7}, // 1e333
-	{0x723627BBB5A4ADB0, 0xB80DC58E81FE95A1}, // 1e334
-	{0xCEC3B1AAA30DD91C, 0xE61136F2227E3B09}, // 1e335
-	{0x213A4F0AA5E8A7B1, 0x8FCAC257558EE4E6}, // 1e336
-	{0xA988E2CD4F62D19D, 0xB3BD72ED2AF29E1F}, // 1e337
-	{0x93EB1B80A33B8605, 0xE0ACCFA875AF45A7}, // 1e338
-	{0xBC72F130660533C3, 0x8C6C01C9498D8B88}, // 1e339
-	{0xEB8FAD7C7F8680B4, 0xAF87023B9BF0EE6A}, // 1e340
-	{0xA67398DB9F6820E1, 0xDB68C2CA82ED2A05}, // 1e341
-	{0x88083F8943A1148C, 0x892179BE91D43A43}, // 1e342
-	{0x6A0A4F6B948959B0, 0xAB69D82E364948D4}, // 1e343
-	{0x848CE34679ABB01C, 0xD6444E39C3DB9B09}, // 1e344
-	{0xF2D80E0C0C0B4E11, 0x85EAB0E41A6940E5}, // 1e345
-	{0x6F8E118F0F0E2195, 0xA7655D1D2103911F}, // 1e346
-	{0x4B7195F2D2D1A9FB, 0xD13EB46469447567}, // 1e347
-}
diff --git a/contrib/go/_std_1.18/src/strconv/ftoa.go b/contrib/go/_std_1.18/src/strconv/ftoa.go
deleted file mode 100644
index eca04b851c..0000000000
--- a/contrib/go/_std_1.18/src/strconv/ftoa.go
+++ /dev/null
@@ -1,582 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Binary to decimal floating point conversion.
-// Algorithm:
-//   1) store mantissa in multiprecision decimal
-//   2) shift decimal by exponent
-//   3) read digits out & format
-
-package strconv
-
-import "math"
-
-// TODO: move elsewhere?
-type floatInfo struct {
-	mantbits uint
-	expbits  uint
-	bias     int
-}
-
-var float32info = floatInfo{23, 8, -127}
-var float64info = floatInfo{52, 11, -1023}
-
-// FormatFloat converts the floating-point number f to a string,
-// according to the format fmt and precision prec. It rounds the
-// result assuming that the original was obtained from a floating-point
-// value of bitSize bits (32 for float32, 64 for float64).
-//
-// The format fmt is one of
-// 'b' (-ddddp±ddd, a binary exponent),
-// 'e' (-d.dddde±dd, a decimal exponent),
-// 'E' (-d.ddddE±dd, a decimal exponent),
-// 'f' (-ddd.dddd, no exponent),
-// 'g' ('e' for large exponents, 'f' otherwise),
-// 'G' ('E' for large exponents, 'f' otherwise),
-// 'x' (-0xd.ddddp±ddd, a hexadecimal fraction and binary exponent), or
-// 'X' (-0Xd.ddddP±ddd, a hexadecimal fraction and binary exponent).
-//
-// The precision prec controls the number of digits (excluding the exponent)
-// printed by the 'e', 'E', 'f', 'g', 'G', 'x', and 'X' formats.
-// For 'e', 'E', 'f', 'x', and 'X', it is the number of digits after the decimal point.
-// For 'g' and 'G' it is the maximum number of significant digits (trailing
-// zeros are removed).
-// The special precision -1 uses the smallest number of digits
-// necessary such that ParseFloat will return f exactly.
-func FormatFloat(f float64, fmt byte, prec, bitSize int) string {
-	return string(genericFtoa(make([]byte, 0, max(prec+4, 24)), f, fmt, prec, bitSize))
-}
-
-// AppendFloat appends the string form of the floating-point number f,
-// as generated by FormatFloat, to dst and returns the extended buffer.
-func AppendFloat(dst []byte, f float64, fmt byte, prec, bitSize int) []byte {
-	return genericFtoa(dst, f, fmt, prec, bitSize)
-}
-
-func genericFtoa(dst []byte, val float64, fmt byte, prec, bitSize int) []byte {
-	var bits uint64
-	var flt *floatInfo
-	switch bitSize {
-	case 32:
-		bits = uint64(math.Float32bits(float32(val)))
-		flt = &float32info
-	case 64:
-		bits = math.Float64bits(val)
-		flt = &float64info
-	default:
-		panic("strconv: illegal AppendFloat/FormatFloat bitSize")
-	}
-
-	neg := bits>>(flt.expbits+flt.mantbits) != 0
-	exp := int(bits>>flt.mantbits) & (1<<flt.expbits - 1)
-	mant := bits & (uint64(1)<<flt.mantbits - 1)
-
-	switch exp {
-	case 1<<flt.expbits - 1:
-		// Inf, NaN
-		var s string
-		switch {
-		case mant != 0:
-			s = "NaN"
-		case neg:
-			s = "-Inf"
-		default:
-			s = "+Inf"
-		}
-		return append(dst, s...)
-
-	case 0:
-		// denormalized
-		exp++
-
-	default:
-		// add implicit top bit
-		mant |= uint64(1) << flt.mantbits
-	}
-	exp += flt.bias
-
-	// Pick off easy binary, hex formats.
-	if fmt == 'b' {
-		return fmtB(dst, neg, mant, exp, flt)
-	}
-	if fmt == 'x' || fmt == 'X' {
-		return fmtX(dst, prec, fmt, neg, mant, exp, flt)
-	}
-
-	if !optimize {
-		return bigFtoa(dst, prec, fmt, neg, mant, exp, flt)
-	}
-
-	var digs decimalSlice
-	ok := false
-	// Negative precision means "only as much as needed to be exact."
-	shortest := prec < 0
-	if shortest {
-		// Use Ryu algorithm.
-		var buf [32]byte
-		digs.d = buf[:]
-		ryuFtoaShortest(&digs, mant, exp-int(flt.mantbits), flt)
-		ok = true
-		// Precision for shortest representation mode.
-		switch fmt {
-		case 'e', 'E':
-			prec = max(digs.nd-1, 0)
-		case 'f':
-			prec = max(digs.nd-digs.dp, 0)
-		case 'g', 'G':
-			prec = digs.nd
-		}
-	} else if fmt != 'f' {
-		// Fixed number of digits.
-		digits := prec
-		switch fmt {
-		case 'e', 'E':
-			digits++
-		case 'g', 'G':
-			if prec == 0 {
-				prec = 1
-			}
-			digits = prec
-		}
-		var buf [24]byte
-		if bitSize == 32 && digits <= 9 {
-			digs.d = buf[:]
-			ryuFtoaFixed32(&digs, uint32(mant), exp-int(flt.mantbits), digits)
-			ok = true
-		} else if digits <= 18 {
-			digs.d = buf[:]
-			ryuFtoaFixed64(&digs, mant, exp-int(flt.mantbits), digits)
-			ok = true
-		}
-	}
-	if !ok {
-		return bigFtoa(dst, prec, fmt, neg, mant, exp, flt)
-	}
-	return formatDigits(dst, shortest, neg, digs, prec, fmt)
-}
-
-// bigFtoa uses multiprecision computations to format a float.
-func bigFtoa(dst []byte, prec int, fmt byte, neg bool, mant uint64, exp int, flt *floatInfo) []byte {
-	d := new(decimal)
-	d.Assign(mant)
-	d.Shift(exp - int(flt.mantbits))
-	var digs decimalSlice
-	shortest := prec < 0
-	if shortest {
-		roundShortest(d, mant, exp, flt)
-		digs = decimalSlice{d: d.d[:], nd: d.nd, dp: d.dp}
-		// Precision for shortest representation mode.
-		switch fmt {
-		case 'e', 'E':
-			prec = digs.nd - 1
-		case 'f':
-			prec = max(digs.nd-digs.dp, 0)
-		case 'g', 'G':
-			prec = digs.nd
-		}
-	} else {
-		// Round appropriately.
-		switch fmt {
-		case 'e', 'E':
-			d.Round(prec + 1)
-		case 'f':
-			d.Round(d.dp + prec)
-		case 'g', 'G':
-			if prec == 0 {
-				prec = 1
-			}
-			d.Round(prec)
-		}
-		digs = decimalSlice{d: d.d[:], nd: d.nd, dp: d.dp}
-	}
-	return formatDigits(dst, shortest, neg, digs, prec, fmt)
-}
-
-func formatDigits(dst []byte, shortest bool, neg bool, digs decimalSlice, prec int, fmt byte) []byte {
-	switch fmt {
-	case 'e', 'E':
-		return fmtE(dst, neg, digs, prec, fmt)
-	case 'f':
-		return fmtF(dst, neg, digs, prec)
-	case 'g', 'G':
-		// trailing fractional zeros in 'e' form will be trimmed.
-		eprec := prec
-		if eprec > digs.nd && digs.nd >= digs.dp {
-			eprec = digs.nd
-		}
-		// %e is used if the exponent from the conversion
-		// is less than -4 or greater than or equal to the precision.
-		// if precision was the shortest possible, use precision 6 for this decision.
-		if shortest {
-			eprec = 6
-		}
-		exp := digs.dp - 1
-		if exp < -4 || exp >= eprec {
-			if prec > digs.nd {
-				prec = digs.nd
-			}
-			return fmtE(dst, neg, digs, prec-1, fmt+'e'-'g')
-		}
-		if prec > digs.dp {
-			prec = digs.nd
-		}
-		return fmtF(dst, neg, digs, max(prec-digs.dp, 0))
-	}
-
-	// unknown format
-	return append(dst, '%', fmt)
-}
-
-// roundShortest rounds d (= mant * 2^exp) to the shortest number of digits
-// that will let the original floating point value be precisely reconstructed.
-func roundShortest(d *decimal, mant uint64, exp int, flt *floatInfo) {
-	// If mantissa is zero, the number is zero; stop now.
-	if mant == 0 {
-		d.nd = 0
-		return
-	}
-
-	// Compute upper and lower such that any decimal number
-	// between upper and lower (possibly inclusive)
-	// will round to the original floating point number.
-
-	// We may see at once that the number is already shortest.
-	//
-	// Suppose d is not denormal, so that 2^exp <= d < 10^dp.
-	// The closest shorter number is at least 10^(dp-nd) away.
-	// The lower/upper bounds computed below are at distance
-	// at most 2^(exp-mantbits).
-	//
-	// So the number is already shortest if 10^(dp-nd) > 2^(exp-mantbits),
-	// or equivalently log2(10)*(dp-nd) > exp-mantbits.
-	// It is true if 332/100*(dp-nd) >= exp-mantbits (log2(10) > 3.32).
-	minexp := flt.bias + 1 // minimum possible exponent
-	if exp > minexp && 332*(d.dp-d.nd) >= 100*(exp-int(flt.mantbits)) {
-		// The number is already shortest.
-		return
-	}
-
-	// d = mant << (exp - mantbits)
-	// Next highest floating point number is mant+1 << exp-mantbits.
-	// Our upper bound is halfway between, mant*2+1 << exp-mantbits-1.
-	upper := new(decimal)
-	upper.Assign(mant*2 + 1)
-	upper.Shift(exp - int(flt.mantbits) - 1)
-
-	// d = mant << (exp - mantbits)
-	// Next lowest floating point number is mant-1 << exp-mantbits,
-	// unless mant-1 drops the significant bit and exp is not the minimum exp,
-	// in which case the next lowest is mant*2-1 << exp-mantbits-1.
-	// Either way, call it mantlo << explo-mantbits.
-	// Our lower bound is halfway between, mantlo*2+1 << explo-mantbits-1.
-	var mantlo uint64
-	var explo int
-	if mant > 1<<flt.mantbits || exp == minexp {
-		mantlo = mant - 1
-		explo = exp
-	} else {
-		mantlo = mant*2 - 1
-		explo = exp - 1
-	}
-	lower := new(decimal)
-	lower.Assign(mantlo*2 + 1)
-	lower.Shift(explo - int(flt.mantbits) - 1)
-
-	// The upper and lower bounds are possible outputs only if
-	// the original mantissa is even, so that IEEE round-to-even
-	// would round to the original mantissa and not the neighbors.
-	inclusive := mant%2 == 0
-
-	// As we walk the digits we want to know whether rounding up would fall
-	// within the upper bound. This is tracked by upperdelta:
-	//
-	// If upperdelta == 0, the digits of d and upper are the same so far.
-	//
-	// If upperdelta == 1, we saw a difference of 1 between d and upper on a
-	// previous digit and subsequently only 9s for d and 0s for upper.
-	// (Thus rounding up may fall outside the bound, if it is exclusive.)
-	//
-	// If upperdelta == 2, then the difference is greater than 1
-	// and we know that rounding up falls within the bound.
-	var upperdelta uint8
-
-	// Now we can figure out the minimum number of digits required.
-	// Walk along until d has distinguished itself from upper and lower.
-	for ui := 0; ; ui++ {
-		// lower, d, and upper may have the decimal points at different
-		// places. In this case upper is the longest, so we iterate from
-		// ui==0 and start li and mi at (possibly) -1.
-		mi := ui - upper.dp + d.dp
-		if mi >= d.nd {
-			break
-		}
-		li := ui - upper.dp + lower.dp
-		l := byte('0') // lower digit
-		if li >= 0 && li < lower.nd {
-			l = lower.d[li]
-		}
-		m := byte('0') // middle digit
-		if mi >= 0 {
-			m = d.d[mi]
-		}
-		u := byte('0') // upper digit
-		if ui < upper.nd {
-			u = upper.d[ui]
-		}
-
-		// Okay to round down (truncate) if lower has a different digit
-		// or if lower is inclusive and is exactly the result of rounding
-		// down (i.e., and we have reached the final digit of lower).
-		okdown := l != m || inclusive && li+1 == lower.nd
-
-		switch {
-		case upperdelta == 0 && m+1 < u:
-			// Example:
-			// m = 12345xxx
-			// u = 12347xxx
-			upperdelta = 2
-		case upperdelta == 0 && m != u:
-			// Example:
-			// m = 12345xxx
-			// u = 12346xxx
-			upperdelta = 1
-		case upperdelta == 1 && (m != '9' || u != '0'):
-			// Example:
-			// m = 1234598x
-			// u = 1234600x
-			upperdelta = 2
-		}
-		// Okay to round up if upper has a different digit and either upper
-		// is inclusive or upper is bigger than the result of rounding up.
-		okup := upperdelta > 0 && (inclusive || upperdelta > 1 || ui+1 < upper.nd)
-
-		// If it's okay to do either, then round to the nearest one.
-		// If it's okay to do only one, do it.
-		switch {
-		case okdown && okup:
-			d.Round(mi + 1)
-			return
-		case okdown:
-			d.RoundDown(mi + 1)
-			return
-		case okup:
-			d.RoundUp(mi + 1)
-			return
-		}
-	}
-}
-
-type decimalSlice struct {
-	d      []byte
-	nd, dp int
-	neg    bool
-}
-
-// %e: -d.ddddde±dd
-func fmtE(dst []byte, neg bool, d decimalSlice, prec int, fmt byte) []byte {
-	// sign
-	if neg {
-		dst = append(dst, '-')
-	}
-
-	// first digit
-	ch := byte('0')
-	if d.nd != 0 {
-		ch = d.d[0]
-	}
-	dst = append(dst, ch)
-
-	// .moredigits
-	if prec > 0 {
-		dst = append(dst, '.')
-		i := 1
-		m := min(d.nd, prec+1)
-		if i < m {
-			dst = append(dst, d.d[i:m]...)
-			i = m
-		}
-		for ; i <= prec; i++ {
-			dst = append(dst, '0')
-		}
-	}
-
-	// e±
-	dst = append(dst, fmt)
-	exp := d.dp - 1
-	if d.nd == 0 { // special case: 0 has exponent 0
-		exp = 0
-	}
-	if exp < 0 {
-		ch = '-'
-		exp = -exp
-	} else {
-		ch = '+'
-	}
-	dst = append(dst, ch)
-
-	// dd or ddd
-	switch {
-	case exp < 10:
-		dst = append(dst, '0', byte(exp)+'0')
-	case exp < 100:
-		dst = append(dst, byte(exp/10)+'0', byte(exp%10)+'0')
-	default:
-		dst = append(dst, byte(exp/100)+'0', byte(exp/10)%10+'0', byte(exp%10)+'0')
-	}
-
-	return dst
-}
-
-// %f: -ddddddd.ddddd
-func fmtF(dst []byte, neg bool, d decimalSlice, prec int) []byte {
-	// sign
-	if neg {
-		dst = append(dst, '-')
-	}
-
-	// integer, padded with zeros as needed.
-	if d.dp > 0 {
-		m := min(d.nd, d.dp)
-		dst = append(dst, d.d[:m]...)
-		for ; m < d.dp; m++ {
-			dst = append(dst, '0')
-		}
-	} else {
-		dst = append(dst, '0')
-	}
-
-	// fraction
-	if prec > 0 {
-		dst = append(dst, '.')
-		for i := 0; i < prec; i++ {
-			ch := byte('0')
-			if j := d.dp + i; 0 <= j && j < d.nd {
-				ch = d.d[j]
-			}
-			dst = append(dst, ch)
-		}
-	}
-
-	return dst
-}
-
-// %b: -ddddddddp±ddd
-func fmtB(dst []byte, neg bool, mant uint64, exp int, flt *floatInfo) []byte {
-	// sign
-	if neg {
-		dst = append(dst, '-')
-	}
-
-	// mantissa
-	dst, _ = formatBits(dst, mant, 10, false, true)
-
-	// p
-	dst = append(dst, 'p')
-
-	// ±exponent
-	exp -= int(flt.mantbits)
-	if exp >= 0 {
-		dst = append(dst, '+')
-	}
-	dst, _ = formatBits(dst, uint64(exp), 10, exp < 0, true)
-
-	return dst
-}
-
-// %x: -0x1.yyyyyyyyp±ddd or -0x0p+0. (y is hex digit, d is decimal digit)
-func fmtX(dst []byte, prec int, fmt byte, neg bool, mant uint64, exp int, flt *floatInfo) []byte {
-	if mant == 0 {
-		exp = 0
-	}
-
-	// Shift digits so leading 1 (if any) is at bit 1<<60.
-	mant <<= 60 - flt.mantbits
-	for mant != 0 && mant&(1<<60) == 0 {
-		mant <<= 1
-		exp--
-	}
-
-	// Round if requested.
-	if prec >= 0 && prec < 15 {
-		shift := uint(prec * 4)
-		extra := (mant << shift) & (1<<60 - 1)
-		mant >>= 60 - shift
-		if extra|(mant&1) > 1<<59 {
-			mant++
-		}
-		mant <<= 60 - shift
-		if mant&(1<<61) != 0 {
-			// Wrapped around.
-			mant >>= 1
-			exp++
-		}
-	}
-
-	hex := lowerhex
-	if fmt == 'X' {
-		hex = upperhex
-	}
-
-	// sign, 0x, leading digit
-	if neg {
-		dst = append(dst, '-')
-	}
-	dst = append(dst, '0', fmt, '0'+byte((mant>>60)&1))
-
-	// .fraction
-	mant <<= 4 // remove leading 0 or 1
-	if prec < 0 && mant != 0 {
-		dst = append(dst, '.')
-		for mant != 0 {
-			dst = append(dst, hex[(mant>>60)&15])
-			mant <<= 4
-		}
-	} else if prec > 0 {
-		dst = append(dst, '.')
-		for i := 0; i < prec; i++ {
-			dst = append(dst, hex[(mant>>60)&15])
-			mant <<= 4
-		}
-	}
-
-	// p±
-	ch := byte('P')
-	if fmt == lower(fmt) {
-		ch = 'p'
-	}
-	dst = append(dst, ch)
-	if exp < 0 {
-		ch = '-'
-		exp = -exp
-	} else {
-		ch = '+'
-	}
-	dst = append(dst, ch)
-
-	// dd or ddd or dddd
-	switch {
-	case exp < 100:
-		dst = append(dst, byte(exp/10)+'0', byte(exp%10)+'0')
-	case exp < 1000:
-		dst = append(dst, byte(exp/100)+'0', byte((exp/10)%10)+'0', byte(exp%10)+'0')
-	default:
-		dst = append(dst, byte(exp/1000)+'0', byte(exp/100)%10+'0', byte((exp/10)%10)+'0', byte(exp%10)+'0')
-	}
-
-	return dst
-}
-
-func min(a, b int) int {
-	if a < b {
-		return a
-	}
-	return b
-}
-
-func max(a, b int) int {
-	if a > b {
-		return a
-	}
-	return b
-}
diff --git a/contrib/go/_std_1.18/src/strconv/ftoaryu.go b/contrib/go/_std_1.18/src/strconv/ftoaryu.go
deleted file mode 100644
index f2e74bed17..0000000000
--- a/contrib/go/_std_1.18/src/strconv/ftoaryu.go
+++ /dev/null
@@ -1,567 +0,0 @@
-// Copyright 2021 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package strconv
-
-import (
-	"math/bits"
-)
-
-// binary to decimal conversion using the Ryū algorithm.
-//
-// See Ulf Adams, "Ryū: Fast Float-to-String Conversion" (doi:10.1145/3192366.3192369)
-//
-// Fixed precision formatting is a variant of the original paper's
-// algorithm, where a single multiplication by 10^k is required,
-// sharing the same rounding guarantees.
-
-// ryuFtoaFixed32 formats mant*(2^exp) with prec decimal digits.
-func ryuFtoaFixed32(d *decimalSlice, mant uint32, exp int, prec int) {
-	if prec < 0 {
-		panic("ryuFtoaFixed32 called with negative prec")
-	}
-	if prec > 9 {
-		panic("ryuFtoaFixed32 called with prec > 9")
-	}
-	// Zero input.
-	if mant == 0 {
-		d.nd, d.dp = 0, 0
-		return
-	}
-	// Renormalize to a 25-bit mantissa.
-	e2 := exp
-	if b := bits.Len32(mant); b < 25 {
-		mant <<= uint(25 - b)
-		e2 += int(b) - 25
-	}
-	// Choose an exponent such that rounded mant*(2^e2)*(10^q) has
-	// at least prec decimal digits, i.e
-	//     mant*(2^e2)*(10^q) >= 10^(prec-1)
-	// Because mant >= 2^24, it is enough to choose:
-	//     2^(e2+24) >= 10^(-q+prec-1)
-	// or q = -mulByLog2Log10(e2+24) + prec - 1
-	q := -mulByLog2Log10(e2+24) + prec - 1
-
-	// Now compute mant*(2^e2)*(10^q).
-	// Is it an exact computation?
-	// Only small positive powers of 10 are exact (5^28 has 66 bits).
-	exact := q <= 27 && q >= 0
-
-	di, dexp2, d0 := mult64bitPow10(mant, e2, q)
-	if dexp2 >= 0 {
-		panic("not enough significant bits after mult64bitPow10")
-	}
-	// As a special case, computation might still be exact, if exponent
-	// was negative and if it amounts to computing an exact division.
-	// In that case, we ignore all lower bits.
-	// Note that division by 10^11 cannot be exact as 5^11 has 26 bits.
-	if q < 0 && q >= -10 && divisibleByPower5(uint64(mant), -q) {
-		exact = true
-		d0 = true
-	}
-	// Remove extra lower bits and keep rounding info.
-	extra := uint(-dexp2)
-	extraMask := uint32(1<<extra - 1)
-
-	di, dfrac := di>>extra, di&extraMask
-	roundUp := false
-	if exact {
-		// If we computed an exact product, d + 1/2
-		// should round to d+1 if 'd' is odd.
-		roundUp = dfrac > 1<<(extra-1) ||
-			(dfrac == 1<<(extra-1) && !d0) ||
-			(dfrac == 1<<(extra-1) && d0 && di&1 == 1)
-	} else {
-		// otherwise, d+1/2 always rounds up because
-		// we truncated below.
-		roundUp = dfrac>>(extra-1) == 1
-	}
-	if dfrac != 0 {
-		d0 = false
-	}
-	// Proceed to the requested number of digits
-	formatDecimal(d, uint64(di), !d0, roundUp, prec)
-	// Adjust exponent
-	d.dp -= q
-}
-
-// ryuFtoaFixed64 formats mant*(2^exp) with prec decimal digits.
-func ryuFtoaFixed64(d *decimalSlice, mant uint64, exp int, prec int) {
-	if prec > 18 {
-		panic("ryuFtoaFixed64 called with prec > 18")
-	}
-	// Zero input.
-	if mant == 0 {
-		d.nd, d.dp = 0, 0
-		return
-	}
-	// Renormalize to a 55-bit mantissa.
-	e2 := exp
-	if b := bits.Len64(mant); b < 55 {
-		mant = mant << uint(55-b)
-		e2 += int(b) - 55
-	}
-	// Choose an exponent such that rounded mant*(2^e2)*(10^q) has
-	// at least prec decimal digits, i.e
-	//     mant*(2^e2)*(10^q) >= 10^(prec-1)
-	// Because mant >= 2^54, it is enough to choose:
-	//     2^(e2+54) >= 10^(-q+prec-1)
-	// or q = -mulByLog2Log10(e2+54) + prec - 1
-	//
-	// The minimal required exponent is -mulByLog2Log10(1025)+18 = -291
-	// The maximal required exponent is mulByLog2Log10(1074)+18 = 342
-	q := -mulByLog2Log10(e2+54) + prec - 1
-
-	// Now compute mant*(2^e2)*(10^q).
-	// Is it an exact computation?
-	// Only small positive powers of 10 are exact (5^55 has 128 bits).
-	exact := q <= 55 && q >= 0
-
-	di, dexp2, d0 := mult128bitPow10(mant, e2, q)
-	if dexp2 >= 0 {
-		panic("not enough significant bits after mult128bitPow10")
-	}
-	// As a special case, computation might still be exact, if exponent
-	// was negative and if it amounts to computing an exact division.
-	// In that case, we ignore all lower bits.
-	// Note that division by 10^23 cannot be exact as 5^23 has 54 bits.
-	if q < 0 && q >= -22 && divisibleByPower5(mant, -q) {
-		exact = true
-		d0 = true
-	}
-	// Remove extra lower bits and keep rounding info.
-	extra := uint(-dexp2)
-	extraMask := uint64(1<<extra - 1)
-
-	di, dfrac := di>>extra, di&extraMask
-	roundUp := false
-	if exact {
-		// If we computed an exact product, d + 1/2
-		// should round to d+1 if 'd' is odd.
-		roundUp = dfrac > 1<<(extra-1) ||
-			(dfrac == 1<<(extra-1) && !d0) ||
-			(dfrac == 1<<(extra-1) && d0 && di&1 == 1)
-	} else {
-		// otherwise, d+1/2 always rounds up because
-		// we truncated below.
-		roundUp = dfrac>>(extra-1) == 1
-	}
-	if dfrac != 0 {
-		d0 = false
-	}
-	// Proceed to the requested number of digits
-	formatDecimal(d, di, !d0, roundUp, prec)
-	// Adjust exponent
-	d.dp -= q
-}
-
-var uint64pow10 = [...]uint64{
-	1, 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9,
-	1e10, 1e11, 1e12, 1e13, 1e14, 1e15, 1e16, 1e17, 1e18, 1e19,
-}
-
-// formatDecimal fills d with at most prec decimal digits
-// of mantissa m. The boolean trunc indicates whether m
-// is truncated compared to the original number being formatted.
-func formatDecimal(d *decimalSlice, m uint64, trunc bool, roundUp bool, prec int) {
-	max := uint64pow10[prec]
-	trimmed := 0
-	for m >= max {
-		a, b := m/10, m%10
-		m = a
-		trimmed++
-		if b > 5 {
-			roundUp = true
-		} else if b < 5 {
-			roundUp = false
-		} else { // b == 5
-			// round up if there are trailing digits,
-			// or if the new value of m is odd (round-to-even convention)
-			roundUp = trunc || m&1 == 1
-		}
-		if b != 0 {
-			trunc = true
-		}
-	}
-	if roundUp {
-		m++
-	}
-	if m >= max {
-		// Happens if di was originally 99999....xx
-		m /= 10
-		trimmed++
-	}
-	// render digits (similar to formatBits)
-	n := uint(prec)
-	d.nd = int(prec)
-	v := m
-	for v >= 100 {
-		var v1, v2 uint64
-		if v>>32 == 0 {
-			v1, v2 = uint64(uint32(v)/100), uint64(uint32(v)%100)
-		} else {
-			v1, v2 = v/100, v%100
-		}
-		n -= 2
-		d.d[n+1] = smallsString[2*v2+1]
-		d.d[n+0] = smallsString[2*v2+0]
-		v = v1
-	}
-	if v > 0 {
-		n--
-		d.d[n] = smallsString[2*v+1]
-	}
-	if v >= 10 {
-		n--
-		d.d[n] = smallsString[2*v]
-	}
-	for d.d[d.nd-1] == '0' {
-		d.nd--
-		trimmed++
-	}
-	d.dp = d.nd + trimmed
-}
-
-// ryuFtoaShortest formats mant*2^exp with prec decimal digits.
-func ryuFtoaShortest(d *decimalSlice, mant uint64, exp int, flt *floatInfo) {
-	if mant == 0 {
-		d.nd, d.dp = 0, 0
-		return
-	}
-	// If input is an exact integer with fewer bits than the mantissa,
-	// the previous and next integer are not admissible representations.
-	if exp <= 0 && bits.TrailingZeros64(mant) >= -exp {
-		mant >>= uint(-exp)
-		ryuDigits(d, mant, mant, mant, true, false)
-		return
-	}
-	ml, mc, mu, e2 := computeBounds(mant, exp, flt)
-	if e2 == 0 {
-		ryuDigits(d, ml, mc, mu, true, false)
-		return
-	}
-	// Find 10^q *larger* than 2^-e2
-	q := mulByLog2Log10(-e2) + 1
-
-	// We are going to multiply by 10^q using 128-bit arithmetic.
-	// The exponent is the same for all 3 numbers.
-	var dl, dc, du uint64
-	var dl0, dc0, du0 bool
-	if flt == &float32info {
-		var dl32, dc32, du32 uint32
-		dl32, _, dl0 = mult64bitPow10(uint32(ml), e2, q)
-		dc32, _, dc0 = mult64bitPow10(uint32(mc), e2, q)
-		du32, e2, du0 = mult64bitPow10(uint32(mu), e2, q)
-		dl, dc, du = uint64(dl32), uint64(dc32), uint64(du32)
-	} else {
-		dl, _, dl0 = mult128bitPow10(ml, e2, q)
-		dc, _, dc0 = mult128bitPow10(mc, e2, q)
-		du, e2, du0 = mult128bitPow10(mu, e2, q)
-	}
-	if e2 >= 0 {
-		panic("not enough significant bits after mult128bitPow10")
-	}
-	// Is it an exact computation?
-	if q > 55 {
-		// Large positive powers of ten are not exact
-		dl0, dc0, du0 = false, false, false
-	}
-	if q < 0 && q >= -24 {
-		// Division by a power of ten may be exact.
-		// (note that 5^25 is a 59-bit number so division by 5^25 is never exact).
-		if divisibleByPower5(ml, -q) {
-			dl0 = true
-		}
-		if divisibleByPower5(mc, -q) {
-			dc0 = true
-		}
-		if divisibleByPower5(mu, -q) {
-			du0 = true
-		}
-	}
-	// Express the results (dl, dc, du)*2^e2 as integers.
-	// Extra bits must be removed and rounding hints computed.
-	extra := uint(-e2)
-	extraMask := uint64(1<<extra - 1)
-	// Now compute the floored, integral base 10 mantissas.
-	dl, fracl := dl>>extra, dl&extraMask
-	dc, fracc := dc>>extra, dc&extraMask
-	du, fracu := du>>extra, du&extraMask
-	// Is it allowed to use 'du' as a result?
-	// It is always allowed when it is truncated, but also
-	// if it is exact and the original binary mantissa is even
-	// When disallowed, we can subtract 1.
-	uok := !du0 || fracu > 0
-	if du0 && fracu == 0 {
-		uok = mant&1 == 0
-	}
-	if !uok {
-		du--
-	}
-	// Is 'dc' the correctly rounded base 10 mantissa?
-	// The correct rounding might be dc+1
-	cup := false // don't round up.
-	if dc0 {
-		// If we computed an exact product, the half integer
-		// should round to next (even) integer if 'dc' is odd.
-		cup = fracc > 1<<(extra-1) ||
-			(fracc == 1<<(extra-1) && dc&1 == 1)
-	} else {
-		// otherwise, the result is a lower truncation of the ideal
-		// result.
-		cup = fracc>>(extra-1) == 1
-	}
-	// Is 'dl' an allowed representation?
-	// Only if it is an exact value, and if the original binary mantissa
-	// was even.
-	lok := dl0 && fracl == 0 && (mant&1 == 0)
-	if !lok {
-		dl++
-	}
-	// We need to remember whether the trimmed digits of 'dc' are zero.
-	c0 := dc0 && fracc == 0
-	// render digits
-	ryuDigits(d, dl, dc, du, c0, cup)
-	d.dp -= q
-}
-
-// mulByLog2Log10 returns math.Floor(x * log(2)/log(10)) for an integer x in
-// the range -1600 <= x && x <= +1600.
-//
-// The range restriction lets us work in faster integer arithmetic instead of
-// slower floating point arithmetic. Correctness is verified by unit tests.
-func mulByLog2Log10(x int) int {
-	// log(2)/log(10) ≈ 0.30102999566 ≈ 78913 / 2^18
-	return (x * 78913) >> 18
-}
-
-// mulByLog10Log2 returns math.Floor(x * log(10)/log(2)) for an integer x in
-// the range -500 <= x && x <= +500.
-//
-// The range restriction lets us work in faster integer arithmetic instead of
-// slower floating point arithmetic. Correctness is verified by unit tests.
-func mulByLog10Log2(x int) int {
-	// log(10)/log(2) ≈ 3.32192809489 ≈ 108853 / 2^15
-	return (x * 108853) >> 15
-}
-
-// computeBounds returns a floating-point vector (l, c, u)×2^e2
-// where the mantissas are 55-bit (or 26-bit) integers, describing the interval
-// represented by the input float64 or float32.
-func computeBounds(mant uint64, exp int, flt *floatInfo) (lower, central, upper uint64, e2 int) {
-	if mant != 1<<flt.mantbits || exp == flt.bias+1-int(flt.mantbits) {
-		// regular case (or denormals)
-		lower, central, upper = 2*mant-1, 2*mant, 2*mant+1
-		e2 = exp - 1
-		return
-	} else {
-		// border of an exponent
-		lower, central, upper = 4*mant-1, 4*mant, 4*mant+2
-		e2 = exp - 2
-		return
-	}
-}
-
-func ryuDigits(d *decimalSlice, lower, central, upper uint64,
-	c0, cup bool) {
-	lhi, llo := divmod1e9(lower)
-	chi, clo := divmod1e9(central)
-	uhi, ulo := divmod1e9(upper)
-	if uhi == 0 {
-		// only low digits (for denormals)
-		ryuDigits32(d, llo, clo, ulo, c0, cup, 8)
-	} else if lhi < uhi {
-		// truncate 9 digits at once.
-		if llo != 0 {
-			lhi++
-		}
-		c0 = c0 && clo == 0
-		cup = (clo > 5e8) || (clo == 5e8 && cup)
-		ryuDigits32(d, lhi, chi, uhi, c0, cup, 8)
-		d.dp += 9
-	} else {
-		d.nd = 0
-		// emit high part
-		n := uint(9)
-		for v := chi; v > 0; {
-			v1, v2 := v/10, v%10
-			v = v1
-			n--
-			d.d[n] = byte(v2 + '0')
-		}
-		d.d = d.d[n:]
-		d.nd = int(9 - n)
-		// emit low part
-		ryuDigits32(d, llo, clo, ulo,
-			c0, cup, d.nd+8)
-	}
-	// trim trailing zeros
-	for d.nd > 0 && d.d[d.nd-1] == '0' {
-		d.nd--
-	}
-	// trim initial zeros
-	for d.nd > 0 && d.d[0] == '0' {
-		d.nd--
-		d.dp--
-		d.d = d.d[1:]
-	}
-}
-
-// ryuDigits32 emits decimal digits for a number less than 1e9.
-func ryuDigits32(d *decimalSlice, lower, central, upper uint32,
-	c0, cup bool, endindex int) {
-	if upper == 0 {
-		d.dp = endindex + 1
-		return
-	}
-	trimmed := 0
-	// Remember last trimmed digit to check for round-up.
-	// c0 will be used to remember zeroness of following digits.
-	cNextDigit := 0
-	for upper > 0 {
-		// Repeatedly compute:
-		// l = Ceil(lower / 10^k)
-		// c = Round(central / 10^k)
-		// u = Floor(upper / 10^k)
-		// and stop when c goes out of the (l, u) interval.
-		l := (lower + 9) / 10
-		c, cdigit := central/10, central%10
-		u := upper / 10
-		if l > u {
-			// don't trim the last digit as it is forbidden to go below l
-			// other, trim and exit now.
-			break
-		}
-		// Check that we didn't cross the lower boundary.
-		// The case where l < u but c == l-1 is essentially impossible,
-		// but may happen if:
-		//    lower   = ..11
-		//    central = ..19
-		//    upper   = ..31
-		// and means that 'central' is very close but less than
-		// an integer ending with many zeros, and usually
-		// the "round-up" logic hides the problem.
-		if l == c+1 && c < u {
-			c++
-			cdigit = 0
-			cup = false
-		}
-		trimmed++
-		// Remember trimmed digits of c
-		c0 = c0 && cNextDigit == 0
-		cNextDigit = int(cdigit)
-		lower, central, upper = l, c, u
-	}
-	// should we round up?
-	if trimmed > 0 {
-		cup = cNextDigit > 5 ||
-			(cNextDigit == 5 && !c0) ||
-			(cNextDigit == 5 && c0 && central&1 == 1)
-	}
-	if central < upper && cup {
-		central++
-	}
-	// We know where the number ends, fill directly
-	endindex -= trimmed
-	v := central
-	n := endindex
-	for n > d.nd {
-		v1, v2 := v/100, v%100
-		d.d[n] = smallsString[2*v2+1]
-		d.d[n-1] = smallsString[2*v2+0]
-		n -= 2
-		v = v1
-	}
-	if n == d.nd {
-		d.d[n] = byte(v + '0')
-	}
-	d.nd = endindex + 1
-	d.dp = d.nd + trimmed
-}
-
-// mult64bitPow10 takes a floating-point input with a 25-bit
-// mantissa and multiplies it with 10^q. The resulting mantissa
-// is m*P >> 57 where P is a 64-bit element of the detailedPowersOfTen tables.
-// It is typically 31 or 32-bit wide.
-// The returned boolean is true if all trimmed bits were zero.
-//
-// That is:
-//     m*2^e2 * round(10^q) = resM * 2^resE + ε
-//     exact = ε == 0
-func mult64bitPow10(m uint32, e2, q int) (resM uint32, resE int, exact bool) {
-	if q == 0 {
-		// P == 1<<63
-		return m << 6, e2 - 6, true
-	}
-	if q < detailedPowersOfTenMinExp10 || detailedPowersOfTenMaxExp10 < q {
-		// This never happens due to the range of float32/float64 exponent
-		panic("mult64bitPow10: power of 10 is out of range")
-	}
-	pow := detailedPowersOfTen[q-detailedPowersOfTenMinExp10][1]
-	if q < 0 {
-		// Inverse powers of ten must be rounded up.
-		pow += 1
-	}
-	hi, lo := bits.Mul64(uint64(m), pow)
-	e2 += mulByLog10Log2(q) - 63 + 57
-	return uint32(hi<<7 | lo>>57), e2, lo<<7 == 0
-}
-
-// mult128bitPow10 takes a floating-point input with a 55-bit
-// mantissa and multiplies it with 10^q. The resulting mantissa
-// is m*P >> 119 where P is a 128-bit element of the detailedPowersOfTen tables.
-// It is typically 63 or 64-bit wide.
-// The returned boolean is true is all trimmed bits were zero.
-//
-// That is:
-//     m*2^e2 * round(10^q) = resM * 2^resE + ε
-//     exact = ε == 0
-func mult128bitPow10(m uint64, e2, q int) (resM uint64, resE int, exact bool) {
-	if q == 0 {
-		// P == 1<<127
-		return m << 8, e2 - 8, true
-	}
-	if q < detailedPowersOfTenMinExp10 || detailedPowersOfTenMaxExp10 < q {
-		// This never happens due to the range of float32/float64 exponent
-		panic("mult128bitPow10: power of 10 is out of range")
-	}
-	pow := detailedPowersOfTen[q-detailedPowersOfTenMinExp10]
-	if q < 0 {
-		// Inverse powers of ten must be rounded up.
-		pow[0] += 1
-	}
-	e2 += mulByLog10Log2(q) - 127 + 119
-
-	// long multiplication
-	l1, l0 := bits.Mul64(m, pow[0])
-	h1, h0 := bits.Mul64(m, pow[1])
-	mid, carry := bits.Add64(l1, h0, 0)
-	h1 += carry
-	return h1<<9 | mid>>55, e2, mid<<9 == 0 && l0 == 0
-}
-
-func divisibleByPower5(m uint64, k int) bool {
-	if m == 0 {
-		return true
-	}
-	for i := 0; i < k; i++ {
-		if m%5 != 0 {
-			return false
-		}
-		m /= 5
-	}
-	return true
-}
-
-// divmod1e9 computes quotient and remainder of division by 1e9,
-// avoiding runtime uint64 division on 32-bit platforms.
-func divmod1e9(x uint64) (uint32, uint32) {
-	if !host32bit {
-		return uint32(x / 1e9), uint32(x % 1e9)
-	}
-	// Use the same sequence of operations as the amd64 compiler.
-	hi, _ := bits.Mul64(x>>1, 0x89705f4136b4a598) // binary digits of 1e-9
-	q := hi >> 28
-	return uint32(q), uint32(x - q*1e9)
-}
diff --git a/contrib/go/_std_1.18/src/strconv/itoa.go b/contrib/go/_std_1.18/src/strconv/itoa.go
deleted file mode 100644
index 45e4192c82..0000000000
--- a/contrib/go/_std_1.18/src/strconv/itoa.go
+++ /dev/null
@@ -1,206 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package strconv
-
-import "math/bits"
-
-const fastSmalls = true // enable fast path for small integers
-
-// FormatUint returns the string representation of i in the given base,
-// for 2 <= base <= 36. The result uses the lower-case letters 'a' to 'z'
-// for digit values >= 10.
-func FormatUint(i uint64, base int) string {
-	if fastSmalls && i < nSmalls && base == 10 {
-		return small(int(i))
-	}
-	_, s := formatBits(nil, i, base, false, false)
-	return s
-}
-
-// FormatInt returns the string representation of i in the given base,
-// for 2 <= base <= 36. The result uses the lower-case letters 'a' to 'z'
-// for digit values >= 10.
-func FormatInt(i int64, base int) string {
-	if fastSmalls && 0 <= i && i < nSmalls && base == 10 {
-		return small(int(i))
-	}
-	_, s := formatBits(nil, uint64(i), base, i < 0, false)
-	return s
-}
-
-// Itoa is equivalent to FormatInt(int64(i), 10).
-func Itoa(i int) string {
-	return FormatInt(int64(i), 10)
-}
-
-// AppendInt appends the string form of the integer i,
-// as generated by FormatInt, to dst and returns the extended buffer.
-func AppendInt(dst []byte, i int64, base int) []byte {
-	if fastSmalls && 0 <= i && i < nSmalls && base == 10 {
-		return append(dst, small(int(i))...)
-	}
-	dst, _ = formatBits(dst, uint64(i), base, i < 0, true)
-	return dst
-}
-
-// AppendUint appends the string form of the unsigned integer i,
-// as generated by FormatUint, to dst and returns the extended buffer.
-func AppendUint(dst []byte, i uint64, base int) []byte {
-	if fastSmalls && i < nSmalls && base == 10 {
-		return append(dst, small(int(i))...)
-	}
-	dst, _ = formatBits(dst, i, base, false, true)
-	return dst
-}
-
-// small returns the string for an i with 0 <= i < nSmalls.
-func small(i int) string {
-	if i < 10 {
-		return digits[i : i+1]
-	}
-	return smallsString[i*2 : i*2+2]
-}
-
-const nSmalls = 100
-
-const smallsString = "00010203040506070809" +
-	"10111213141516171819" +
-	"20212223242526272829" +
-	"30313233343536373839" +
-	"40414243444546474849" +
-	"50515253545556575859" +
-	"60616263646566676869" +
-	"70717273747576777879" +
-	"80818283848586878889" +
-	"90919293949596979899"
-
-const host32bit = ^uint(0)>>32 == 0
-
-const digits = "0123456789abcdefghijklmnopqrstuvwxyz"
-
-// formatBits computes the string representation of u in the given base.
-// If neg is set, u is treated as negative int64 value. If append_ is
-// set, the string is appended to dst and the resulting byte slice is
-// returned as the first result value; otherwise the string is returned
-// as the second result value.
-//
-func formatBits(dst []byte, u uint64, base int, neg, append_ bool) (d []byte, s string) {
-	if base < 2 || base > len(digits) {
-		panic("strconv: illegal AppendInt/FormatInt base")
-	}
-	// 2 <= base && base <= len(digits)
-
-	var a [64 + 1]byte // +1 for sign of 64bit value in base 2
-	i := len(a)
-
-	if neg {
-		u = -u
-	}
-
-	// convert bits
-	// We use uint values where we can because those will
-	// fit into a single register even on a 32bit machine.
-	if base == 10 {
-		// common case: use constants for / because
-		// the compiler can optimize it into a multiply+shift
-
-		if host32bit {
-			// convert the lower digits using 32bit operations
-			for u >= 1e9 {
-				// Avoid using r = a%b in addition to q = a/b
-				// since 64bit division and modulo operations
-				// are calculated by runtime functions on 32bit machines.
-				q := u / 1e9
-				us := uint(u - q*1e9) // u % 1e9 fits into a uint
-				for j := 4; j > 0; j-- {
-					is := us % 100 * 2
-					us /= 100
-					i -= 2
-					a[i+1] = smallsString[is+1]
-					a[i+0] = smallsString[is+0]
-				}
-
-				// us < 10, since it contains the last digit
-				// from the initial 9-digit us.
-				i--
-				a[i] = smallsString[us*2+1]
-
-				u = q
-			}
-			// u < 1e9
-		}
-
-		// u guaranteed to fit into a uint
-		us := uint(u)
-		for us >= 100 {
-			is := us % 100 * 2
-			us /= 100
-			i -= 2
-			a[i+1] = smallsString[is+1]
-			a[i+0] = smallsString[is+0]
-		}
-
-		// us < 100
-		is := us * 2
-		i--
-		a[i] = smallsString[is+1]
-		if us >= 10 {
-			i--
-			a[i] = smallsString[is]
-		}
-
-	} else if isPowerOfTwo(base) {
-		// Use shifts and masks instead of / and %.
-		// Base is a power of 2 and 2 <= base <= len(digits) where len(digits) is 36.
-		// The largest power of 2 below or equal to 36 is 32, which is 1 << 5;
-		// i.e., the largest possible shift count is 5. By &-ind that value with
-		// the constant 7 we tell the compiler that the shift count is always
-		// less than 8 which is smaller than any register width. This allows
-		// the compiler to generate better code for the shift operation.
-		shift := uint(bits.TrailingZeros(uint(base))) & 7
-		b := uint64(base)
-		m := uint(base) - 1 // == 1<<shift - 1
-		for u >= b {
-			i--
-			a[i] = digits[uint(u)&m]
-			u >>= shift
-		}
-		// u < base
-		i--
-		a[i] = digits[uint(u)]
-	} else {
-		// general case
-		b := uint64(base)
-		for u >= b {
-			i--
-			// Avoid using r = a%b in addition to q = a/b
-			// since 64bit division and modulo operations
-			// are calculated by runtime functions on 32bit machines.
-			q := u / b
-			a[i] = digits[uint(u-q*b)]
-			u = q
-		}
-		// u < base
-		i--
-		a[i] = digits[uint(u)]
-	}
-
-	// add sign, if any
-	if neg {
-		i--
-		a[i] = '-'
-	}
-
-	if append_ {
-		d = append(dst, a[i:]...)
-		return
-	}
-	s = string(a[i:])
-	return
-}
-
-func isPowerOfTwo(x int) bool {
-	return x&(x-1) == 0
-}
diff --git a/contrib/go/_std_1.18/src/strconv/quote.go b/contrib/go/_std_1.18/src/strconv/quote.go
deleted file mode 100644
index d2814b92da..0000000000
--- a/contrib/go/_std_1.18/src/strconv/quote.go
+++ /dev/null
@@ -1,598 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:generate go run makeisprint.go -output isprint.go
-
-package strconv
-
-import (
-	"unicode/utf8"
-)
-
-const (
-	lowerhex = "0123456789abcdef"
-	upperhex = "0123456789ABCDEF"
-)
-
-// contains reports whether the string contains the byte c.
-func contains(s string, c byte) bool {
-	return index(s, c) != -1
-}
-
-func quoteWith(s string, quote byte, ASCIIonly, graphicOnly bool) string {
-	return string(appendQuotedWith(make([]byte, 0, 3*len(s)/2), s, quote, ASCIIonly, graphicOnly))
-}
-
-func quoteRuneWith(r rune, quote byte, ASCIIonly, graphicOnly bool) string {
-	return string(appendQuotedRuneWith(nil, r, quote, ASCIIonly, graphicOnly))
-}
-
-func appendQuotedWith(buf []byte, s string, quote byte, ASCIIonly, graphicOnly bool) []byte {
-	// Often called with big strings, so preallocate. If there's quoting,
-	// this is conservative but still helps a lot.
-	if cap(buf)-len(buf) < len(s) {
-		nBuf := make([]byte, len(buf), len(buf)+1+len(s)+1)
-		copy(nBuf, buf)
-		buf = nBuf
-	}
-	buf = append(buf, quote)
-	for width := 0; len(s) > 0; s = s[width:] {
-		r := rune(s[0])
-		width = 1
-		if r >= utf8.RuneSelf {
-			r, width = utf8.DecodeRuneInString(s)
-		}
-		if width == 1 && r == utf8.RuneError {
-			buf = append(buf, `\x`...)
-			buf = append(buf, lowerhex[s[0]>>4])
-			buf = append(buf, lowerhex[s[0]&0xF])
-			continue
-		}
-		buf = appendEscapedRune(buf, r, quote, ASCIIonly, graphicOnly)
-	}
-	buf = append(buf, quote)
-	return buf
-}
-
-func appendQuotedRuneWith(buf []byte, r rune, quote byte, ASCIIonly, graphicOnly bool) []byte {
-	buf = append(buf, quote)
-	if !utf8.ValidRune(r) {
-		r = utf8.RuneError
-	}
-	buf = appendEscapedRune(buf, r, quote, ASCIIonly, graphicOnly)
-	buf = append(buf, quote)
-	return buf
-}
-
-func appendEscapedRune(buf []byte, r rune, quote byte, ASCIIonly, graphicOnly bool) []byte {
-	var runeTmp [utf8.UTFMax]byte
-	if r == rune(quote) || r == '\\' { // always backslashed
-		buf = append(buf, '\\')
-		buf = append(buf, byte(r))
-		return buf
-	}
-	if ASCIIonly {
-		if r < utf8.RuneSelf && IsPrint(r) {
-			buf = append(buf, byte(r))
-			return buf
-		}
-	} else if IsPrint(r) || graphicOnly && isInGraphicList(r) {
-		n := utf8.EncodeRune(runeTmp[:], r)
-		buf = append(buf, runeTmp[:n]...)
-		return buf
-	}
-	switch r {
-	case '\a':
-		buf = append(buf, `\a`...)
-	case '\b':
-		buf = append(buf, `\b`...)
-	case '\f':
-		buf = append(buf, `\f`...)
-	case '\n':
-		buf = append(buf, `\n`...)
-	case '\r':
-		buf = append(buf, `\r`...)
-	case '\t':
-		buf = append(buf, `\t`...)
-	case '\v':
-		buf = append(buf, `\v`...)
-	default:
-		switch {
-		case r < ' ':
-			buf = append(buf, `\x`...)
-			buf = append(buf, lowerhex[byte(r)>>4])
-			buf = append(buf, lowerhex[byte(r)&0xF])
-		case !utf8.ValidRune(r):
-			r = 0xFFFD
-			fallthrough
-		case r < 0x10000:
-			buf = append(buf, `\u`...)
-			for s := 12; s >= 0; s -= 4 {
-				buf = append(buf, lowerhex[r>>uint(s)&0xF])
-			}
-		default:
-			buf = append(buf, `\U`...)
-			for s := 28; s >= 0; s -= 4 {
-				buf = append(buf, lowerhex[r>>uint(s)&0xF])
-			}
-		}
-	}
-	return buf
-}
-
-// Quote returns a double-quoted Go string literal representing s. The
-// returned string uses Go escape sequences (\t, \n, \xFF, \u0100) for
-// control characters and non-printable characters as defined by
-// IsPrint.
-func Quote(s string) string {
-	return quoteWith(s, '"', false, false)
-}
-
-// AppendQuote appends a double-quoted Go string literal representing s,
-// as generated by Quote, to dst and returns the extended buffer.
-func AppendQuote(dst []byte, s string) []byte {
-	return appendQuotedWith(dst, s, '"', false, false)
-}
-
-// QuoteToASCII returns a double-quoted Go string literal representing s.
-// The returned string uses Go escape sequences (\t, \n, \xFF, \u0100) for
-// non-ASCII characters and non-printable characters as defined by IsPrint.
-func QuoteToASCII(s string) string {
-	return quoteWith(s, '"', true, false)
-}
-
-// AppendQuoteToASCII appends a double-quoted Go string literal representing s,
-// as generated by QuoteToASCII, to dst and returns the extended buffer.
-func AppendQuoteToASCII(dst []byte, s string) []byte {
-	return appendQuotedWith(dst, s, '"', true, false)
-}
-
-// QuoteToGraphic returns a double-quoted Go string literal representing s.
-// The returned string leaves Unicode graphic characters, as defined by
-// IsGraphic, unchanged and uses Go escape sequences (\t, \n, \xFF, \u0100)
-// for non-graphic characters.
-func QuoteToGraphic(s string) string {
-	return quoteWith(s, '"', false, true)
-}
-
-// AppendQuoteToGraphic appends a double-quoted Go string literal representing s,
-// as generated by QuoteToGraphic, to dst and returns the extended buffer.
-func AppendQuoteToGraphic(dst []byte, s string) []byte {
-	return appendQuotedWith(dst, s, '"', false, true)
-}
-
-// QuoteRune returns a single-quoted Go character literal representing the
-// rune. The returned string uses Go escape sequences (\t, \n, \xFF, \u0100)
-// for control characters and non-printable characters as defined by IsPrint.
-func QuoteRune(r rune) string {
-	return quoteRuneWith(r, '\'', false, false)
-}
-
-// AppendQuoteRune appends a single-quoted Go character literal representing the rune,
-// as generated by QuoteRune, to dst and returns the extended buffer.
-func AppendQuoteRune(dst []byte, r rune) []byte {
-	return appendQuotedRuneWith(dst, r, '\'', false, false)
-}
-
-// QuoteRuneToASCII returns a single-quoted Go character literal representing
-// the rune. The returned string uses Go escape sequences (\t, \n, \xFF,
-// \u0100) for non-ASCII characters and non-printable characters as defined
-// by IsPrint.
-func QuoteRuneToASCII(r rune) string {
-	return quoteRuneWith(r, '\'', true, false)
-}
-
-// AppendQuoteRuneToASCII appends a single-quoted Go character literal representing the rune,
-// as generated by QuoteRuneToASCII, to dst and returns the extended buffer.
-func AppendQuoteRuneToASCII(dst []byte, r rune) []byte {
-	return appendQuotedRuneWith(dst, r, '\'', true, false)
-}
-
-// QuoteRuneToGraphic returns a single-quoted Go character literal representing
-// the rune. If the rune is not a Unicode graphic character,
-// as defined by IsGraphic, the returned string will use a Go escape sequence
-// (\t, \n, \xFF, \u0100).
-func QuoteRuneToGraphic(r rune) string {
-	return quoteRuneWith(r, '\'', false, true)
-}
-
-// AppendQuoteRuneToGraphic appends a single-quoted Go character literal representing the rune,
-// as generated by QuoteRuneToGraphic, to dst and returns the extended buffer.
-func AppendQuoteRuneToGraphic(dst []byte, r rune) []byte {
-	return appendQuotedRuneWith(dst, r, '\'', false, true)
-}
-
-// CanBackquote reports whether the string s can be represented
-// unchanged as a single-line backquoted string without control
-// characters other than tab.
-func CanBackquote(s string) bool {
-	for len(s) > 0 {
-		r, wid := utf8.DecodeRuneInString(s)
-		s = s[wid:]
-		if wid > 1 {
-			if r == '\ufeff' {
-				return false // BOMs are invisible and should not be quoted.
-			}
-			continue // All other multibyte runes are correctly encoded and assumed printable.
-		}
-		if r == utf8.RuneError {
-			return false
-		}
-		if (r < ' ' && r != '\t') || r == '`' || r == '\u007F' {
-			return false
-		}
-	}
-	return true
-}
-
-func unhex(b byte) (v rune, ok bool) {
-	c := rune(b)
-	switch {
-	case '0' <= c && c <= '9':
-		return c - '0', true
-	case 'a' <= c && c <= 'f':
-		return c - 'a' + 10, true
-	case 'A' <= c && c <= 'F':
-		return c - 'A' + 10, true
-	}
-	return
-}
-
-// UnquoteChar decodes the first character or byte in the escaped string
-// or character literal represented by the string s.
-// It returns four values:
-//
-//	1) value, the decoded Unicode code point or byte value;
-//	2) multibyte, a boolean indicating whether the decoded character requires a multibyte UTF-8 representation;
-//	3) tail, the remainder of the string after the character; and
-//	4) an error that will be nil if the character is syntactically valid.
-//
-// The second argument, quote, specifies the type of literal being parsed
-// and therefore which escaped quote character is permitted.
-// If set to a single quote, it permits the sequence \' and disallows unescaped '.
-// If set to a double quote, it permits \" and disallows unescaped ".
-// If set to zero, it does not permit either escape and allows both quote characters to appear unescaped.
-func UnquoteChar(s string, quote byte) (value rune, multibyte bool, tail string, err error) {
-	// easy cases
-	if len(s) == 0 {
-		err = ErrSyntax
-		return
-	}
-	switch c := s[0]; {
-	case c == quote && (quote == '\'' || quote == '"'):
-		err = ErrSyntax
-		return
-	case c >= utf8.RuneSelf:
-		r, size := utf8.DecodeRuneInString(s)
-		return r, true, s[size:], nil
-	case c != '\\':
-		return rune(s[0]), false, s[1:], nil
-	}
-
-	// hard case: c is backslash
-	if len(s) <= 1 {
-		err = ErrSyntax
-		return
-	}
-	c := s[1]
-	s = s[2:]
-
-	switch c {
-	case 'a':
-		value = '\a'
-	case 'b':
-		value = '\b'
-	case 'f':
-		value = '\f'
-	case 'n':
-		value = '\n'
-	case 'r':
-		value = '\r'
-	case 't':
-		value = '\t'
-	case 'v':
-		value = '\v'
-	case 'x', 'u', 'U':
-		n := 0
-		switch c {
-		case 'x':
-			n = 2
-		case 'u':
-			n = 4
-		case 'U':
-			n = 8
-		}
-		var v rune
-		if len(s) < n {
-			err = ErrSyntax
-			return
-		}
-		for j := 0; j < n; j++ {
-			x, ok := unhex(s[j])
-			if !ok {
-				err = ErrSyntax
-				return
-			}
-			v = v<<4 | x
-		}
-		s = s[n:]
-		if c == 'x' {
-			// single-byte string, possibly not UTF-8
-			value = v
-			break
-		}
-		if !utf8.ValidRune(v) {
-			err = ErrSyntax
-			return
-		}
-		value = v
-		multibyte = true
-	case '0', '1', '2', '3', '4', '5', '6', '7':
-		v := rune(c) - '0'
-		if len(s) < 2 {
-			err = ErrSyntax
-			return
-		}
-		for j := 0; j < 2; j++ { // one digit already; two more
-			x := rune(s[j]) - '0'
-			if x < 0 || x > 7 {
-				err = ErrSyntax
-				return
-			}
-			v = (v << 3) | x
-		}
-		s = s[2:]
-		if v > 255 {
-			err = ErrSyntax
-			return
-		}
-		value = v
-	case '\\':
-		value = '\\'
-	case '\'', '"':
-		if c != quote {
-			err = ErrSyntax
-			return
-		}
-		value = rune(c)
-	default:
-		err = ErrSyntax
-		return
-	}
-	tail = s
-	return
-}
-
-// QuotedPrefix returns the quoted string (as understood by Unquote) at the prefix of s.
-// If s does not start with a valid quoted string, QuotedPrefix returns an error.
-func QuotedPrefix(s string) (string, error) {
-	out, _, err := unquote(s, false)
-	return out, err
-}
-
-// Unquote interprets s as a single-quoted, double-quoted,
-// or backquoted Go string literal, returning the string value
-// that s quotes.  (If s is single-quoted, it would be a Go
-// character literal; Unquote returns the corresponding
-// one-character string.)
-func Unquote(s string) (string, error) {
-	out, rem, err := unquote(s, true)
-	if len(rem) > 0 {
-		return "", ErrSyntax
-	}
-	return out, err
-}
-
-// unquote parses a quoted string at the start of the input,
-// returning the parsed prefix, the remaining suffix, and any parse errors.
-// If unescape is true, the parsed prefix is unescaped,
-// otherwise the input prefix is provided verbatim.
-func unquote(in string, unescape bool) (out, rem string, err error) {
-	// Determine the quote form and optimistically find the terminating quote.
-	if len(in) < 2 {
-		return "", in, ErrSyntax
-	}
-	quote := in[0]
-	end := index(in[1:], quote)
-	if end < 0 {
-		return "", in, ErrSyntax
-	}
-	end += 2 // position after terminating quote; may be wrong if escape sequences are present
-
-	switch quote {
-	case '`':
-		switch {
-		case !unescape:
-			out = in[:end] // include quotes
-		case !contains(in[:end], '\r'):
-			out = in[len("`") : end-len("`")] // exclude quotes
-		default:
-			// Carriage return characters ('\r') inside raw string literals
-			// are discarded from the raw string value.
-			buf := make([]byte, 0, end-len("`")-len("\r")-len("`"))
-			for i := len("`"); i < end-len("`"); i++ {
-				if in[i] != '\r' {
-					buf = append(buf, in[i])
-				}
-			}
-			out = string(buf)
-		}
-		// NOTE: Prior implementations did not verify that raw strings consist
-		// of valid UTF-8 characters and we continue to not verify it as such.
-		// The Go specification does not explicitly require valid UTF-8,
-		// but only mention that it is implicitly valid for Go source code
-		// (which must be valid UTF-8).
-		return out, in[end:], nil
-	case '"', '\'':
-		// Handle quoted strings without any escape sequences.
-		if !contains(in[:end], '\\') && !contains(in[:end], '\n') {
-			var valid bool
-			switch quote {
-			case '"':
-				valid = utf8.ValidString(in[len(`"`) : end-len(`"`)])
-			case '\'':
-				r, n := utf8.DecodeRuneInString(in[len("'") : end-len("'")])
-				valid = len("'")+n+len("'") == end && (r != utf8.RuneError || n != 1)
-			}
-			if valid {
-				out = in[:end]
-				if unescape {
-					out = out[1 : end-1] // exclude quotes
-				}
-				return out, in[end:], nil
-			}
-		}
-
-		// Handle quoted strings with escape sequences.
-		var buf []byte
-		in0 := in
-		in = in[1:] // skip starting quote
-		if unescape {
-			buf = make([]byte, 0, 3*end/2) // try to avoid more allocations
-		}
-		for len(in) > 0 && in[0] != quote {
-			// Process the next character,
-			// rejecting any unescaped newline characters which are invalid.
-			r, multibyte, rem, err := UnquoteChar(in, quote)
-			if in[0] == '\n' || err != nil {
-				return "", in0, ErrSyntax
-			}
-			in = rem
-
-			// Append the character if unescaping the input.
-			if unescape {
-				if r < utf8.RuneSelf || !multibyte {
-					buf = append(buf, byte(r))
-				} else {
-					var arr [utf8.UTFMax]byte
-					n := utf8.EncodeRune(arr[:], r)
-					buf = append(buf, arr[:n]...)
-				}
-			}
-
-			// Single quoted strings must be a single character.
-			if quote == '\'' {
-				break
-			}
-		}
-
-		// Verify that the string ends with a terminating quote.
-		if !(len(in) > 0 && in[0] == quote) {
-			return "", in0, ErrSyntax
-		}
-		in = in[1:] // skip terminating quote
-
-		if unescape {
-			return string(buf), in, nil
-		}
-		return in0[:len(in0)-len(in)], in, nil
-	default:
-		return "", in, ErrSyntax
-	}
-}
-
-// bsearch16 returns the smallest i such that a[i] >= x.
-// If there is no such i, bsearch16 returns len(a).
-func bsearch16(a []uint16, x uint16) int {
-	i, j := 0, len(a)
-	for i < j {
-		h := i + (j-i)>>1
-		if a[h] < x {
-			i = h + 1
-		} else {
-			j = h
-		}
-	}
-	return i
-}
-
-// bsearch32 returns the smallest i such that a[i] >= x.
-// If there is no such i, bsearch32 returns len(a).
-func bsearch32(a []uint32, x uint32) int {
-	i, j := 0, len(a)
-	for i < j {
-		h := i + (j-i)>>1
-		if a[h] < x {
-			i = h + 1
-		} else {
-			j = h
-		}
-	}
-	return i
-}
-
-// TODO: IsPrint is a local implementation of unicode.IsPrint, verified by the tests
-// to give the same answer. It allows this package not to depend on unicode,
-// and therefore not pull in all the Unicode tables. If the linker were better
-// at tossing unused tables, we could get rid of this implementation.
-// That would be nice.
-
-// IsPrint reports whether the rune is defined as printable by Go, with
-// the same definition as unicode.IsPrint: letters, numbers, punctuation,
-// symbols and ASCII space.
-func IsPrint(r rune) bool {
-	// Fast check for Latin-1
-	if r <= 0xFF {
-		if 0x20 <= r && r <= 0x7E {
-			// All the ASCII is printable from space through DEL-1.
-			return true
-		}
-		if 0xA1 <= r && r <= 0xFF {
-			// Similarly for ¡ through ÿ...
-			return r != 0xAD // ...except for the bizarre soft hyphen.
-		}
-		return false
-	}
-
-	// Same algorithm, either on uint16 or uint32 value.
-	// First, find first i such that isPrint[i] >= x.
-	// This is the index of either the start or end of a pair that might span x.
-	// The start is even (isPrint[i&^1]) and the end is odd (isPrint[i|1]).
-	// If we find x in a range, make sure x is not in isNotPrint list.
-
-	if 0 <= r && r < 1<<16 {
-		rr, isPrint, isNotPrint := uint16(r), isPrint16, isNotPrint16
-		i := bsearch16(isPrint, rr)
-		if i >= len(isPrint) || rr < isPrint[i&^1] || isPrint[i|1] < rr {
-			return false
-		}
-		j := bsearch16(isNotPrint, rr)
-		return j >= len(isNotPrint) || isNotPrint[j] != rr
-	}
-
-	rr, isPrint, isNotPrint := uint32(r), isPrint32, isNotPrint32
-	i := bsearch32(isPrint, rr)
-	if i >= len(isPrint) || rr < isPrint[i&^1] || isPrint[i|1] < rr {
-		return false
-	}
-	if r >= 0x20000 {
-		return true
-	}
-	r -= 0x10000
-	j := bsearch16(isNotPrint, uint16(r))
-	return j >= len(isNotPrint) || isNotPrint[j] != uint16(r)
-}
-
-// IsGraphic reports whether the rune is defined as a Graphic by Unicode. Such
-// characters include letters, marks, numbers, punctuation, symbols, and
-// spaces, from categories L, M, N, P, S, and Zs.
-func IsGraphic(r rune) bool {
-	if IsPrint(r) {
-		return true
-	}
-	return isInGraphicList(r)
-}
-
-// isInGraphicList reports whether the rune is in the isGraphic list. This separation
-// from IsGraphic allows quoteWith to avoid two calls to IsPrint.
-// Should be called only if IsPrint fails.
-func isInGraphicList(r rune) bool {
-	// We know r must fit in 16 bits - see makeisprint.go.
-	if r > 0xFFFF {
-		return false
-	}
-	rr := uint16(r)
-	i := bsearch16(isGraphic, rr)
-	return i < len(isGraphic) && rr == isGraphic[i]
-}
diff --git a/contrib/go/_std_1.18/src/strings/builder.go b/contrib/go/_std_1.18/src/strings/builder.go
deleted file mode 100644
index ba4df618bf..0000000000
--- a/contrib/go/_std_1.18/src/strings/builder.go
+++ /dev/null
@@ -1,125 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package strings
-
-import (
-	"unicode/utf8"
-	"unsafe"
-)
-
-// A Builder is used to efficiently build a string using Write methods.
-// It minimizes memory copying. The zero value is ready to use.
-// Do not copy a non-zero Builder.
-type Builder struct {
-	addr *Builder // of receiver, to detect copies by value
-	buf  []byte
-}
-
-// noescape hides a pointer from escape analysis. It is the identity function
-// but escape analysis doesn't think the output depends on the input.
-// noescape is inlined and currently compiles down to zero instructions.
-// USE CAREFULLY!
-// This was copied from the runtime; see issues 23382 and 7921.
-//go:nosplit
-//go:nocheckptr
-func noescape(p unsafe.Pointer) unsafe.Pointer {
-	x := uintptr(p)
-	return unsafe.Pointer(x ^ 0)
-}
-
-func (b *Builder) copyCheck() {
-	if b.addr == nil {
-		// This hack works around a failing of Go's escape analysis
-		// that was causing b to escape and be heap allocated.
-		// See issue 23382.
-		// TODO: once issue 7921 is fixed, this should be reverted to
-		// just "b.addr = b".
-		b.addr = (*Builder)(noescape(unsafe.Pointer(b)))
-	} else if b.addr != b {
-		panic("strings: illegal use of non-zero Builder copied by value")
-	}
-}
-
-// String returns the accumulated string.
-func (b *Builder) String() string {
-	return *(*string)(unsafe.Pointer(&b.buf))
-}
-
-// Len returns the number of accumulated bytes; b.Len() == len(b.String()).
-func (b *Builder) Len() int { return len(b.buf) }
-
-// Cap returns the capacity of the builder's underlying byte slice. It is the
-// total space allocated for the string being built and includes any bytes
-// already written.
-func (b *Builder) Cap() int { return cap(b.buf) }
-
-// Reset resets the Builder to be empty.
-func (b *Builder) Reset() {
-	b.addr = nil
-	b.buf = nil
-}
-
-// grow copies the buffer to a new, larger buffer so that there are at least n
-// bytes of capacity beyond len(b.buf).
-func (b *Builder) grow(n int) {
-	buf := make([]byte, len(b.buf), 2*cap(b.buf)+n)
-	copy(buf, b.buf)
-	b.buf = buf
-}
-
-// Grow grows b's capacity, if necessary, to guarantee space for
-// another n bytes. After Grow(n), at least n bytes can be written to b
-// without another allocation. If n is negative, Grow panics.
-func (b *Builder) Grow(n int) {
-	b.copyCheck()
-	if n < 0 {
-		panic("strings.Builder.Grow: negative count")
-	}
-	if cap(b.buf)-len(b.buf) < n {
-		b.grow(n)
-	}
-}
-
-// Write appends the contents of p to b's buffer.
-// Write always returns len(p), nil.
-func (b *Builder) Write(p []byte) (int, error) {
-	b.copyCheck()
-	b.buf = append(b.buf, p...)
-	return len(p), nil
-}
-
-// WriteByte appends the byte c to b's buffer.
-// The returned error is always nil.
-func (b *Builder) WriteByte(c byte) error {
-	b.copyCheck()
-	b.buf = append(b.buf, c)
-	return nil
-}
-
-// WriteRune appends the UTF-8 encoding of Unicode code point r to b's buffer.
-// It returns the length of r and a nil error.
-func (b *Builder) WriteRune(r rune) (int, error) {
-	b.copyCheck()
-	// Compare as uint32 to correctly handle negative runes.
-	if uint32(r) < utf8.RuneSelf {
-		b.buf = append(b.buf, byte(r))
-		return 1, nil
-	}
-	l := len(b.buf)
-	if cap(b.buf)-l < utf8.UTFMax {
-		b.grow(utf8.UTFMax)
-	}
-	n := utf8.EncodeRune(b.buf[l:l+utf8.UTFMax], r)
-	b.buf = b.buf[:l+n]
-	return n, nil
-}
-
-// WriteString appends the contents of s to b's buffer.
-// It returns the length of s and a nil error.
-func (b *Builder) WriteString(s string) (int, error) {
-	b.copyCheck()
-	b.buf = append(b.buf, s...)
-	return len(s), nil
-}
diff --git a/contrib/go/_std_1.18/src/strings/replace.go b/contrib/go/_std_1.18/src/strings/replace.go
deleted file mode 100644
index ee728bb22b..0000000000
--- a/contrib/go/_std_1.18/src/strings/replace.go
+++ /dev/null
@@ -1,569 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package strings
-
-import (
-	"io"
-	"sync"
-)
-
-// Replacer replaces a list of strings with replacements.
-// It is safe for concurrent use by multiple goroutines.
-type Replacer struct {
-	once   sync.Once // guards buildOnce method
-	r      replacer
-	oldnew []string
-}
-
-// replacer is the interface that a replacement algorithm needs to implement.
-type replacer interface {
-	Replace(s string) string
-	WriteString(w io.Writer, s string) (n int, err error)
-}
-
-// NewReplacer returns a new Replacer from a list of old, new string
-// pairs. Replacements are performed in the order they appear in the
-// target string, without overlapping matches. The old string
-// comparisons are done in argument order.
-//
-// NewReplacer panics if given an odd number of arguments.
-func NewReplacer(oldnew ...string) *Replacer {
-	if len(oldnew)%2 == 1 {
-		panic("strings.NewReplacer: odd argument count")
-	}
-	return &Replacer{oldnew: append([]string(nil), oldnew...)}
-}
-
-func (r *Replacer) buildOnce() {
-	r.r = r.build()
-	r.oldnew = nil
-}
-
-func (b *Replacer) build() replacer {
-	oldnew := b.oldnew
-	if len(oldnew) == 2 && len(oldnew[0]) > 1 {
-		return makeSingleStringReplacer(oldnew[0], oldnew[1])
-	}
-
-	allNewBytes := true
-	for i := 0; i < len(oldnew); i += 2 {
-		if len(oldnew[i]) != 1 {
-			return makeGenericReplacer(oldnew)
-		}
-		if len(oldnew[i+1]) != 1 {
-			allNewBytes = false
-		}
-	}
-
-	if allNewBytes {
-		r := byteReplacer{}
-		for i := range r {
-			r[i] = byte(i)
-		}
-		// The first occurrence of old->new map takes precedence
-		// over the others with the same old string.
-		for i := len(oldnew) - 2; i >= 0; i -= 2 {
-			o := oldnew[i][0]
-			n := oldnew[i+1][0]
-			r[o] = n
-		}
-		return &r
-	}
-
-	r := byteStringReplacer{toReplace: make([]string, 0, len(oldnew)/2)}
-	// The first occurrence of old->new map takes precedence
-	// over the others with the same old string.
-	for i := len(oldnew) - 2; i >= 0; i -= 2 {
-		o := oldnew[i][0]
-		n := oldnew[i+1]
-		// To avoid counting repetitions multiple times.
-		if r.replacements[o] == nil {
-			// We need to use string([]byte{o}) instead of string(o),
-			// to avoid utf8 encoding of o.
-			// E. g. byte(150) produces string of length 2.
-			r.toReplace = append(r.toReplace, string([]byte{o}))
-		}
-		r.replacements[o] = []byte(n)
-
-	}
-	return &r
-}
-
-// Replace returns a copy of s with all replacements performed.
-func (r *Replacer) Replace(s string) string {
-	r.once.Do(r.buildOnce)
-	return r.r.Replace(s)
-}
-
-// WriteString writes s to w with all replacements performed.
-func (r *Replacer) WriteString(w io.Writer, s string) (n int, err error) {
-	r.once.Do(r.buildOnce)
-	return r.r.WriteString(w, s)
-}
-
-// trieNode is a node in a lookup trie for prioritized key/value pairs. Keys
-// and values may be empty. For example, the trie containing keys "ax", "ay",
-// "bcbc", "x" and "xy" could have eight nodes:
-//
-//  n0  -
-//  n1  a-
-//  n2  .x+
-//  n3  .y+
-//  n4  b-
-//  n5  .cbc+
-//  n6  x+
-//  n7  .y+
-//
-// n0 is the root node, and its children are n1, n4 and n6; n1's children are
-// n2 and n3; n4's child is n5; n6's child is n7. Nodes n0, n1 and n4 (marked
-// with a trailing "-") are partial keys, and nodes n2, n3, n5, n6 and n7
-// (marked with a trailing "+") are complete keys.
-type trieNode struct {
-	// value is the value of the trie node's key/value pair. It is empty if
-	// this node is not a complete key.
-	value string
-	// priority is the priority (higher is more important) of the trie node's
-	// key/value pair; keys are not necessarily matched shortest- or longest-
-	// first. Priority is positive if this node is a complete key, and zero
-	// otherwise. In the example above, positive/zero priorities are marked
-	// with a trailing "+" or "-".
-	priority int
-
-	// A trie node may have zero, one or more child nodes:
-	//  * if the remaining fields are zero, there are no children.
-	//  * if prefix and next are non-zero, there is one child in next.
-	//  * if table is non-zero, it defines all the children.
-	//
-	// Prefixes are preferred over tables when there is one child, but the
-	// root node always uses a table for lookup efficiency.
-
-	// prefix is the difference in keys between this trie node and the next.
-	// In the example above, node n4 has prefix "cbc" and n4's next node is n5.
-	// Node n5 has no children and so has zero prefix, next and table fields.
-	prefix string
-	next   *trieNode
-
-	// table is a lookup table indexed by the next byte in the key, after
-	// remapping that byte through genericReplacer.mapping to create a dense
-	// index. In the example above, the keys only use 'a', 'b', 'c', 'x' and
-	// 'y', which remap to 0, 1, 2, 3 and 4. All other bytes remap to 5, and
-	// genericReplacer.tableSize will be 5. Node n0's table will be
-	// []*trieNode{ 0:n1, 1:n4, 3:n6 }, where the 0, 1 and 3 are the remapped
-	// 'a', 'b' and 'x'.
-	table []*trieNode
-}
-
-func (t *trieNode) add(key, val string, priority int, r *genericReplacer) {
-	if key == "" {
-		if t.priority == 0 {
-			t.value = val
-			t.priority = priority
-		}
-		return
-	}
-
-	if t.prefix != "" {
-		// Need to split the prefix among multiple nodes.
-		var n int // length of the longest common prefix
-		for ; n < len(t.prefix) && n < len(key); n++ {
-			if t.prefix[n] != key[n] {
-				break
-			}
-		}
-		if n == len(t.prefix) {
-			t.next.add(key[n:], val, priority, r)
-		} else if n == 0 {
-			// First byte differs, start a new lookup table here. Looking up
-			// what is currently t.prefix[0] will lead to prefixNode, and
-			// looking up key[0] will lead to keyNode.
-			var prefixNode *trieNode
-			if len(t.prefix) == 1 {
-				prefixNode = t.next
-			} else {
-				prefixNode = &trieNode{
-					prefix: t.prefix[1:],
-					next:   t.next,
-				}
-			}
-			keyNode := new(trieNode)
-			t.table = make([]*trieNode, r.tableSize)
-			t.table[r.mapping[t.prefix[0]]] = prefixNode
-			t.table[r.mapping[key[0]]] = keyNode
-			t.prefix = ""
-			t.next = nil
-			keyNode.add(key[1:], val, priority, r)
-		} else {
-			// Insert new node after the common section of the prefix.
-			next := &trieNode{
-				prefix: t.prefix[n:],
-				next:   t.next,
-			}
-			t.prefix = t.prefix[:n]
-			t.next = next
-			next.add(key[n:], val, priority, r)
-		}
-	} else if t.table != nil {
-		// Insert into existing table.
-		m := r.mapping[key[0]]
-		if t.table[m] == nil {
-			t.table[m] = new(trieNode)
-		}
-		t.table[m].add(key[1:], val, priority, r)
-	} else {
-		t.prefix = key
-		t.next = new(trieNode)
-		t.next.add("", val, priority, r)
-	}
-}
-
-func (r *genericReplacer) lookup(s string, ignoreRoot bool) (val string, keylen int, found bool) {
-	// Iterate down the trie to the end, and grab the value and keylen with
-	// the highest priority.
-	bestPriority := 0
-	node := &r.root
-	n := 0
-	for node != nil {
-		if node.priority > bestPriority && !(ignoreRoot && node == &r.root) {
-			bestPriority = node.priority
-			val = node.value
-			keylen = n
-			found = true
-		}
-
-		if s == "" {
-			break
-		}
-		if node.table != nil {
-			index := r.mapping[s[0]]
-			if int(index) == r.tableSize {
-				break
-			}
-			node = node.table[index]
-			s = s[1:]
-			n++
-		} else if node.prefix != "" && HasPrefix(s, node.prefix) {
-			n += len(node.prefix)
-			s = s[len(node.prefix):]
-			node = node.next
-		} else {
-			break
-		}
-	}
-	return
-}
-
-// genericReplacer is the fully generic algorithm.
-// It's used as a fallback when nothing faster can be used.
-type genericReplacer struct {
-	root trieNode
-	// tableSize is the size of a trie node's lookup table. It is the number
-	// of unique key bytes.
-	tableSize int
-	// mapping maps from key bytes to a dense index for trieNode.table.
-	mapping [256]byte
-}
-
-func makeGenericReplacer(oldnew []string) *genericReplacer {
-	r := new(genericReplacer)
-	// Find each byte used, then assign them each an index.
-	for i := 0; i < len(oldnew); i += 2 {
-		key := oldnew[i]
-		for j := 0; j < len(key); j++ {
-			r.mapping[key[j]] = 1
-		}
-	}
-
-	for _, b := range r.mapping {
-		r.tableSize += int(b)
-	}
-
-	var index byte
-	for i, b := range r.mapping {
-		if b == 0 {
-			r.mapping[i] = byte(r.tableSize)
-		} else {
-			r.mapping[i] = index
-			index++
-		}
-	}
-	// Ensure root node uses a lookup table (for performance).
-	r.root.table = make([]*trieNode, r.tableSize)
-
-	for i := 0; i < len(oldnew); i += 2 {
-		r.root.add(oldnew[i], oldnew[i+1], len(oldnew)-i, r)
-	}
-	return r
-}
-
-type appendSliceWriter []byte
-
-// Write writes to the buffer to satisfy io.Writer.
-func (w *appendSliceWriter) Write(p []byte) (int, error) {
-	*w = append(*w, p...)
-	return len(p), nil
-}
-
-// WriteString writes to the buffer without string->[]byte->string allocations.
-func (w *appendSliceWriter) WriteString(s string) (int, error) {
-	*w = append(*w, s...)
-	return len(s), nil
-}
-
-type stringWriter struct {
-	w io.Writer
-}
-
-func (w stringWriter) WriteString(s string) (int, error) {
-	return w.w.Write([]byte(s))
-}
-
-func getStringWriter(w io.Writer) io.StringWriter {
-	sw, ok := w.(io.StringWriter)
-	if !ok {
-		sw = stringWriter{w}
-	}
-	return sw
-}
-
-func (r *genericReplacer) Replace(s string) string {
-	buf := make(appendSliceWriter, 0, len(s))
-	r.WriteString(&buf, s)
-	return string(buf)
-}
-
-func (r *genericReplacer) WriteString(w io.Writer, s string) (n int, err error) {
-	sw := getStringWriter(w)
-	var last, wn int
-	var prevMatchEmpty bool
-	for i := 0; i <= len(s); {
-		// Fast path: s[i] is not a prefix of any pattern.
-		if i != len(s) && r.root.priority == 0 {
-			index := int(r.mapping[s[i]])
-			if index == r.tableSize || r.root.table[index] == nil {
-				i++
-				continue
-			}
-		}
-
-		// Ignore the empty match iff the previous loop found the empty match.
-		val, keylen, match := r.lookup(s[i:], prevMatchEmpty)
-		prevMatchEmpty = match && keylen == 0
-		if match {
-			wn, err = sw.WriteString(s[last:i])
-			n += wn
-			if err != nil {
-				return
-			}
-			wn, err = sw.WriteString(val)
-			n += wn
-			if err != nil {
-				return
-			}
-			i += keylen
-			last = i
-			continue
-		}
-		i++
-	}
-	if last != len(s) {
-		wn, err = sw.WriteString(s[last:])
-		n += wn
-	}
-	return
-}
-
-// singleStringReplacer is the implementation that's used when there is only
-// one string to replace (and that string has more than one byte).
-type singleStringReplacer struct {
-	finder *stringFinder
-	// value is the new string that replaces that pattern when it's found.
-	value string
-}
-
-func makeSingleStringReplacer(pattern string, value string) *singleStringReplacer {
-	return &singleStringReplacer{finder: makeStringFinder(pattern), value: value}
-}
-
-func (r *singleStringReplacer) Replace(s string) string {
-	var buf Builder
-	i, matched := 0, false
-	for {
-		match := r.finder.next(s[i:])
-		if match == -1 {
-			break
-		}
-		matched = true
-		buf.Grow(match + len(r.value))
-		buf.WriteString(s[i : i+match])
-		buf.WriteString(r.value)
-		i += match + len(r.finder.pattern)
-	}
-	if !matched {
-		return s
-	}
-	buf.WriteString(s[i:])
-	return buf.String()
-}
-
-func (r *singleStringReplacer) WriteString(w io.Writer, s string) (n int, err error) {
-	sw := getStringWriter(w)
-	var i, wn int
-	for {
-		match := r.finder.next(s[i:])
-		if match == -1 {
-			break
-		}
-		wn, err = sw.WriteString(s[i : i+match])
-		n += wn
-		if err != nil {
-			return
-		}
-		wn, err = sw.WriteString(r.value)
-		n += wn
-		if err != nil {
-			return
-		}
-		i += match + len(r.finder.pattern)
-	}
-	wn, err = sw.WriteString(s[i:])
-	n += wn
-	return
-}
-
-// byteReplacer is the implementation that's used when all the "old"
-// and "new" values are single ASCII bytes.
-// The array contains replacement bytes indexed by old byte.
-type byteReplacer [256]byte
-
-func (r *byteReplacer) Replace(s string) string {
-	var buf []byte // lazily allocated
-	for i := 0; i < len(s); i++ {
-		b := s[i]
-		if r[b] != b {
-			if buf == nil {
-				buf = []byte(s)
-			}
-			buf[i] = r[b]
-		}
-	}
-	if buf == nil {
-		return s
-	}
-	return string(buf)
-}
-
-func (r *byteReplacer) WriteString(w io.Writer, s string) (n int, err error) {
-	// TODO(bradfitz): use io.WriteString with slices of s, avoiding allocation.
-	bufsize := 32 << 10
-	if len(s) < bufsize {
-		bufsize = len(s)
-	}
-	buf := make([]byte, bufsize)
-
-	for len(s) > 0 {
-		ncopy := copy(buf, s)
-		s = s[ncopy:]
-		for i, b := range buf[:ncopy] {
-			buf[i] = r[b]
-		}
-		wn, err := w.Write(buf[:ncopy])
-		n += wn
-		if err != nil {
-			return n, err
-		}
-	}
-	return n, nil
-}
-
-// byteStringReplacer is the implementation that's used when all the
-// "old" values are single ASCII bytes but the "new" values vary in size.
-type byteStringReplacer struct {
-	// replacements contains replacement byte slices indexed by old byte.
-	// A nil []byte means that the old byte should not be replaced.
-	replacements [256][]byte
-	// toReplace keeps a list of bytes to replace. Depending on length of toReplace
-	// and length of target string it may be faster to use Count, or a plain loop.
-	// We store single byte as a string, because Count takes a string.
-	toReplace []string
-}
-
-// countCutOff controls the ratio of a string length to a number of replacements
-// at which (*byteStringReplacer).Replace switches algorithms.
-// For strings with higher ration of length to replacements than that value,
-// we call Count, for each replacement from toReplace.
-// For strings, with a lower ratio we use simple loop, because of Count overhead.
-// countCutOff is an empirically determined overhead multiplier.
-// TODO(tocarip) revisit once we have register-based abi/mid-stack inlining.
-const countCutOff = 8
-
-func (r *byteStringReplacer) Replace(s string) string {
-	newSize := len(s)
-	anyChanges := false
-	// Is it faster to use Count?
-	if len(r.toReplace)*countCutOff <= len(s) {
-		for _, x := range r.toReplace {
-			if c := Count(s, x); c != 0 {
-				// The -1 is because we are replacing 1 byte with len(replacements[b]) bytes.
-				newSize += c * (len(r.replacements[x[0]]) - 1)
-				anyChanges = true
-			}
-
-		}
-	} else {
-		for i := 0; i < len(s); i++ {
-			b := s[i]
-			if r.replacements[b] != nil {
-				// See above for explanation of -1
-				newSize += len(r.replacements[b]) - 1
-				anyChanges = true
-			}
-		}
-	}
-	if !anyChanges {
-		return s
-	}
-	buf := make([]byte, newSize)
-	j := 0
-	for i := 0; i < len(s); i++ {
-		b := s[i]
-		if r.replacements[b] != nil {
-			j += copy(buf[j:], r.replacements[b])
-		} else {
-			buf[j] = b
-			j++
-		}
-	}
-	return string(buf)
-}
-
-func (r *byteStringReplacer) WriteString(w io.Writer, s string) (n int, err error) {
-	sw := getStringWriter(w)
-	last := 0
-	for i := 0; i < len(s); i++ {
-		b := s[i]
-		if r.replacements[b] == nil {
-			continue
-		}
-		if last != i {
-			nw, err := sw.WriteString(s[last:i])
-			n += nw
-			if err != nil {
-				return n, err
-			}
-		}
-		last = i + 1
-		nw, err := w.Write(r.replacements[b])
-		n += nw
-		if err != nil {
-			return n, err
-		}
-	}
-	if last != len(s) {
-		var nw int
-		nw, err = sw.WriteString(s[last:])
-		n += nw
-	}
-	return
-}
diff --git a/contrib/go/_std_1.18/src/strings/strings.go b/contrib/go/_std_1.18/src/strings/strings.go
deleted file mode 100644
index 5793d9e26f..0000000000
--- a/contrib/go/_std_1.18/src/strings/strings.go
+++ /dev/null
@@ -1,1186 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package strings implements simple functions to manipulate UTF-8 encoded strings.
-//
-// For information about UTF-8 strings in Go, see https://blog.golang.org/strings.
-package strings
-
-import (
-	"internal/bytealg"
-	"unicode"
-	"unicode/utf8"
-)
-
-// explode splits s into a slice of UTF-8 strings,
-// one string per Unicode character up to a maximum of n (n < 0 means no limit).
-// Invalid UTF-8 sequences become correct encodings of U+FFFD.
-func explode(s string, n int) []string {
-	l := utf8.RuneCountInString(s)
-	if n < 0 || n > l {
-		n = l
-	}
-	a := make([]string, n)
-	for i := 0; i < n-1; i++ {
-		ch, size := utf8.DecodeRuneInString(s)
-		a[i] = s[:size]
-		s = s[size:]
-		if ch == utf8.RuneError {
-			a[i] = string(utf8.RuneError)
-		}
-	}
-	if n > 0 {
-		a[n-1] = s
-	}
-	return a
-}
-
-// Count counts the number of non-overlapping instances of substr in s.
-// If substr is an empty string, Count returns 1 + the number of Unicode code points in s.
-func Count(s, substr string) int {
-	// special case
-	if len(substr) == 0 {
-		return utf8.RuneCountInString(s) + 1
-	}
-	if len(substr) == 1 {
-		return bytealg.CountString(s, substr[0])
-	}
-	n := 0
-	for {
-		i := Index(s, substr)
-		if i == -1 {
-			return n
-		}
-		n++
-		s = s[i+len(substr):]
-	}
-}
-
-// Contains reports whether substr is within s.
-func Contains(s, substr string) bool {
-	return Index(s, substr) >= 0
-}
-
-// ContainsAny reports whether any Unicode code points in chars are within s.
-func ContainsAny(s, chars string) bool {
-	return IndexAny(s, chars) >= 0
-}
-
-// ContainsRune reports whether the Unicode code point r is within s.
-func ContainsRune(s string, r rune) bool {
-	return IndexRune(s, r) >= 0
-}
-
-// LastIndex returns the index of the last instance of substr in s, or -1 if substr is not present in s.
-func LastIndex(s, substr string) int {
-	n := len(substr)
-	switch {
-	case n == 0:
-		return len(s)
-	case n == 1:
-		return LastIndexByte(s, substr[0])
-	case n == len(s):
-		if substr == s {
-			return 0
-		}
-		return -1
-	case n > len(s):
-		return -1
-	}
-	// Rabin-Karp search from the end of the string
-	hashss, pow := bytealg.HashStrRev(substr)
-	last := len(s) - n
-	var h uint32
-	for i := len(s) - 1; i >= last; i-- {
-		h = h*bytealg.PrimeRK + uint32(s[i])
-	}
-	if h == hashss && s[last:] == substr {
-		return last
-	}
-	for i := last - 1; i >= 0; i-- {
-		h *= bytealg.PrimeRK
-		h += uint32(s[i])
-		h -= pow * uint32(s[i+n])
-		if h == hashss && s[i:i+n] == substr {
-			return i
-		}
-	}
-	return -1
-}
-
-// IndexByte returns the index of the first instance of c in s, or -1 if c is not present in s.
-func IndexByte(s string, c byte) int {
-	return bytealg.IndexByteString(s, c)
-}
-
-// IndexRune returns the index of the first instance of the Unicode code point
-// r, or -1 if rune is not present in s.
-// If r is utf8.RuneError, it returns the first instance of any
-// invalid UTF-8 byte sequence.
-func IndexRune(s string, r rune) int {
-	switch {
-	case 0 <= r && r < utf8.RuneSelf:
-		return IndexByte(s, byte(r))
-	case r == utf8.RuneError:
-		for i, r := range s {
-			if r == utf8.RuneError {
-				return i
-			}
-		}
-		return -1
-	case !utf8.ValidRune(r):
-		return -1
-	default:
-		return Index(s, string(r))
-	}
-}
-
-// IndexAny returns the index of the first instance of any Unicode code point
-// from chars in s, or -1 if no Unicode code point from chars is present in s.
-func IndexAny(s, chars string) int {
-	if chars == "" {
-		// Avoid scanning all of s.
-		return -1
-	}
-	if len(chars) == 1 {
-		// Avoid scanning all of s.
-		r := rune(chars[0])
-		if r >= utf8.RuneSelf {
-			r = utf8.RuneError
-		}
-		return IndexRune(s, r)
-	}
-	if len(s) > 8 {
-		if as, isASCII := makeASCIISet(chars); isASCII {
-			for i := 0; i < len(s); i++ {
-				if as.contains(s[i]) {
-					return i
-				}
-			}
-			return -1
-		}
-	}
-	for i, c := range s {
-		if IndexRune(chars, c) >= 0 {
-			return i
-		}
-	}
-	return -1
-}
-
-// LastIndexAny returns the index of the last instance of any Unicode code
-// point from chars in s, or -1 if no Unicode code point from chars is
-// present in s.
-func LastIndexAny(s, chars string) int {
-	if chars == "" {
-		// Avoid scanning all of s.
-		return -1
-	}
-	if len(s) == 1 {
-		rc := rune(s[0])
-		if rc >= utf8.RuneSelf {
-			rc = utf8.RuneError
-		}
-		if IndexRune(chars, rc) >= 0 {
-			return 0
-		}
-		return -1
-	}
-	if len(s) > 8 {
-		if as, isASCII := makeASCIISet(chars); isASCII {
-			for i := len(s) - 1; i >= 0; i-- {
-				if as.contains(s[i]) {
-					return i
-				}
-			}
-			return -1
-		}
-	}
-	if len(chars) == 1 {
-		rc := rune(chars[0])
-		if rc >= utf8.RuneSelf {
-			rc = utf8.RuneError
-		}
-		for i := len(s); i > 0; {
-			r, size := utf8.DecodeLastRuneInString(s[:i])
-			i -= size
-			if rc == r {
-				return i
-			}
-		}
-		return -1
-	}
-	for i := len(s); i > 0; {
-		r, size := utf8.DecodeLastRuneInString(s[:i])
-		i -= size
-		if IndexRune(chars, r) >= 0 {
-			return i
-		}
-	}
-	return -1
-}
-
-// LastIndexByte returns the index of the last instance of c in s, or -1 if c is not present in s.
-func LastIndexByte(s string, c byte) int {
-	for i := len(s) - 1; i >= 0; i-- {
-		if s[i] == c {
-			return i
-		}
-	}
-	return -1
-}
-
-// Generic split: splits after each instance of sep,
-// including sepSave bytes of sep in the subarrays.
-func genSplit(s, sep string, sepSave, n int) []string {
-	if n == 0 {
-		return nil
-	}
-	if sep == "" {
-		return explode(s, n)
-	}
-	if n < 0 {
-		n = Count(s, sep) + 1
-	}
-
-	a := make([]string, n)
-	n--
-	i := 0
-	for i < n {
-		m := Index(s, sep)
-		if m < 0 {
-			break
-		}
-		a[i] = s[:m+sepSave]
-		s = s[m+len(sep):]
-		i++
-	}
-	a[i] = s
-	return a[:i+1]
-}
-
-// SplitN slices s into substrings separated by sep and returns a slice of
-// the substrings between those separators.
-//
-// The count determines the number of substrings to return:
-//   n > 0: at most n substrings; the last substring will be the unsplit remainder.
-//   n == 0: the result is nil (zero substrings)
-//   n < 0: all substrings
-//
-// Edge cases for s and sep (for example, empty strings) are handled
-// as described in the documentation for Split.
-//
-// To split around the first instance of a separator, see Cut.
-func SplitN(s, sep string, n int) []string { return genSplit(s, sep, 0, n) }
-
-// SplitAfterN slices s into substrings after each instance of sep and
-// returns a slice of those substrings.
-//
-// The count determines the number of substrings to return:
-//   n > 0: at most n substrings; the last substring will be the unsplit remainder.
-//   n == 0: the result is nil (zero substrings)
-//   n < 0: all substrings
-//
-// Edge cases for s and sep (for example, empty strings) are handled
-// as described in the documentation for SplitAfter.
-func SplitAfterN(s, sep string, n int) []string {
-	return genSplit(s, sep, len(sep), n)
-}
-
-// Split slices s into all substrings separated by sep and returns a slice of
-// the substrings between those separators.
-//
-// If s does not contain sep and sep is not empty, Split returns a
-// slice of length 1 whose only element is s.
-//
-// If sep is empty, Split splits after each UTF-8 sequence. If both s
-// and sep are empty, Split returns an empty slice.
-//
-// It is equivalent to SplitN with a count of -1.
-//
-// To split around the first instance of a separator, see Cut.
-func Split(s, sep string) []string { return genSplit(s, sep, 0, -1) }
-
-// SplitAfter slices s into all substrings after each instance of sep and
-// returns a slice of those substrings.
-//
-// If s does not contain sep and sep is not empty, SplitAfter returns
-// a slice of length 1 whose only element is s.
-//
-// If sep is empty, SplitAfter splits after each UTF-8 sequence. If
-// both s and sep are empty, SplitAfter returns an empty slice.
-//
-// It is equivalent to SplitAfterN with a count of -1.
-func SplitAfter(s, sep string) []string {
-	return genSplit(s, sep, len(sep), -1)
-}
-
-var asciiSpace = [256]uint8{'\t': 1, '\n': 1, '\v': 1, '\f': 1, '\r': 1, ' ': 1}
-
-// Fields splits the string s around each instance of one or more consecutive white space
-// characters, as defined by unicode.IsSpace, returning a slice of substrings of s or an
-// empty slice if s contains only white space.
-func Fields(s string) []string {
-	// First count the fields.
-	// This is an exact count if s is ASCII, otherwise it is an approximation.
-	n := 0
-	wasSpace := 1
-	// setBits is used to track which bits are set in the bytes of s.
-	setBits := uint8(0)
-	for i := 0; i < len(s); i++ {
-		r := s[i]
-		setBits |= r
-		isSpace := int(asciiSpace[r])
-		n += wasSpace & ^isSpace
-		wasSpace = isSpace
-	}
-
-	if setBits >= utf8.RuneSelf {
-		// Some runes in the input string are not ASCII.
-		return FieldsFunc(s, unicode.IsSpace)
-	}
-	// ASCII fast path
-	a := make([]string, n)
-	na := 0
-	fieldStart := 0
-	i := 0
-	// Skip spaces in the front of the input.
-	for i < len(s) && asciiSpace[s[i]] != 0 {
-		i++
-	}
-	fieldStart = i
-	for i < len(s) {
-		if asciiSpace[s[i]] == 0 {
-			i++
-			continue
-		}
-		a[na] = s[fieldStart:i]
-		na++
-		i++
-		// Skip spaces in between fields.
-		for i < len(s) && asciiSpace[s[i]] != 0 {
-			i++
-		}
-		fieldStart = i
-	}
-	if fieldStart < len(s) { // Last field might end at EOF.
-		a[na] = s[fieldStart:]
-	}
-	return a
-}
-
-// FieldsFunc splits the string s at each run of Unicode code points c satisfying f(c)
-// and returns an array of slices of s. If all code points in s satisfy f(c) or the
-// string is empty, an empty slice is returned.
-//
-// FieldsFunc makes no guarantees about the order in which it calls f(c)
-// and assumes that f always returns the same value for a given c.
-func FieldsFunc(s string, f func(rune) bool) []string {
-	// A span is used to record a slice of s of the form s[start:end].
-	// The start index is inclusive and the end index is exclusive.
-	type span struct {
-		start int
-		end   int
-	}
-	spans := make([]span, 0, 32)
-
-	// Find the field start and end indices.
-	// Doing this in a separate pass (rather than slicing the string s
-	// and collecting the result substrings right away) is significantly
-	// more efficient, possibly due to cache effects.
-	start := -1 // valid span start if >= 0
-	for end, rune := range s {
-		if f(rune) {
-			if start >= 0 {
-				spans = append(spans, span{start, end})
-				// Set start to a negative value.
-				// Note: using -1 here consistently and reproducibly
-				// slows down this code by a several percent on amd64.
-				start = ^start
-			}
-		} else {
-			if start < 0 {
-				start = end
-			}
-		}
-	}
-
-	// Last field might end at EOF.
-	if start >= 0 {
-		spans = append(spans, span{start, len(s)})
-	}
-
-	// Create strings from recorded field indices.
-	a := make([]string, len(spans))
-	for i, span := range spans {
-		a[i] = s[span.start:span.end]
-	}
-
-	return a
-}
-
-// Join concatenates the elements of its first argument to create a single string. The separator
-// string sep is placed between elements in the resulting string.
-func Join(elems []string, sep string) string {
-	switch len(elems) {
-	case 0:
-		return ""
-	case 1:
-		return elems[0]
-	}
-	n := len(sep) * (len(elems) - 1)
-	for i := 0; i < len(elems); i++ {
-		n += len(elems[i])
-	}
-
-	var b Builder
-	b.Grow(n)
-	b.WriteString(elems[0])
-	for _, s := range elems[1:] {
-		b.WriteString(sep)
-		b.WriteString(s)
-	}
-	return b.String()
-}
-
-// HasPrefix tests whether the string s begins with prefix.
-func HasPrefix(s, prefix string) bool {
-	return len(s) >= len(prefix) && s[0:len(prefix)] == prefix
-}
-
-// HasSuffix tests whether the string s ends with suffix.
-func HasSuffix(s, suffix string) bool {
-	return len(s) >= len(suffix) && s[len(s)-len(suffix):] == suffix
-}
-
-// Map returns a copy of the string s with all its characters modified
-// according to the mapping function. If mapping returns a negative value, the character is
-// dropped from the string with no replacement.
-func Map(mapping func(rune) rune, s string) string {
-	// In the worst case, the string can grow when mapped, making
-	// things unpleasant. But it's so rare we barge in assuming it's
-	// fine. It could also shrink but that falls out naturally.
-
-	// The output buffer b is initialized on demand, the first
-	// time a character differs.
-	var b Builder
-
-	for i, c := range s {
-		r := mapping(c)
-		if r == c && c != utf8.RuneError {
-			continue
-		}
-
-		var width int
-		if c == utf8.RuneError {
-			c, width = utf8.DecodeRuneInString(s[i:])
-			if width != 1 && r == c {
-				continue
-			}
-		} else {
-			width = utf8.RuneLen(c)
-		}
-
-		b.Grow(len(s) + utf8.UTFMax)
-		b.WriteString(s[:i])
-		if r >= 0 {
-			b.WriteRune(r)
-		}
-
-		s = s[i+width:]
-		break
-	}
-
-	// Fast path for unchanged input
-	if b.Cap() == 0 { // didn't call b.Grow above
-		return s
-	}
-
-	for _, c := range s {
-		r := mapping(c)
-
-		if r >= 0 {
-			// common case
-			// Due to inlining, it is more performant to determine if WriteByte should be
-			// invoked rather than always call WriteRune
-			if r < utf8.RuneSelf {
-				b.WriteByte(byte(r))
-			} else {
-				// r is not a ASCII rune.
-				b.WriteRune(r)
-			}
-		}
-	}
-
-	return b.String()
-}
-
-// Repeat returns a new string consisting of count copies of the string s.
-//
-// It panics if count is negative or if
-// the result of (len(s) * count) overflows.
-func Repeat(s string, count int) string {
-	if count == 0 {
-		return ""
-	}
-
-	// Since we cannot return an error on overflow,
-	// we should panic if the repeat will generate
-	// an overflow.
-	// See Issue golang.org/issue/16237
-	if count < 0 {
-		panic("strings: negative Repeat count")
-	} else if len(s)*count/count != len(s) {
-		panic("strings: Repeat count causes overflow")
-	}
-
-	n := len(s) * count
-	var b Builder
-	b.Grow(n)
-	b.WriteString(s)
-	for b.Len() < n {
-		if b.Len() <= n/2 {
-			b.WriteString(b.String())
-		} else {
-			b.WriteString(b.String()[:n-b.Len()])
-			break
-		}
-	}
-	return b.String()
-}
-
-// ToUpper returns s with all Unicode letters mapped to their upper case.
-func ToUpper(s string) string {
-	isASCII, hasLower := true, false
-	for i := 0; i < len(s); i++ {
-		c := s[i]
-		if c >= utf8.RuneSelf {
-			isASCII = false
-			break
-		}
-		hasLower = hasLower || ('a' <= c && c <= 'z')
-	}
-
-	if isASCII { // optimize for ASCII-only strings.
-		if !hasLower {
-			return s
-		}
-		var b Builder
-		b.Grow(len(s))
-		for i := 0; i < len(s); i++ {
-			c := s[i]
-			if 'a' <= c && c <= 'z' {
-				c -= 'a' - 'A'
-			}
-			b.WriteByte(c)
-		}
-		return b.String()
-	}
-	return Map(unicode.ToUpper, s)
-}
-
-// ToLower returns s with all Unicode letters mapped to their lower case.
-func ToLower(s string) string {
-	isASCII, hasUpper := true, false
-	for i := 0; i < len(s); i++ {
-		c := s[i]
-		if c >= utf8.RuneSelf {
-			isASCII = false
-			break
-		}
-		hasUpper = hasUpper || ('A' <= c && c <= 'Z')
-	}
-
-	if isASCII { // optimize for ASCII-only strings.
-		if !hasUpper {
-			return s
-		}
-		var b Builder
-		b.Grow(len(s))
-		for i := 0; i < len(s); i++ {
-			c := s[i]
-			if 'A' <= c && c <= 'Z' {
-				c += 'a' - 'A'
-			}
-			b.WriteByte(c)
-		}
-		return b.String()
-	}
-	return Map(unicode.ToLower, s)
-}
-
-// ToTitle returns a copy of the string s with all Unicode letters mapped to
-// their Unicode title case.
-func ToTitle(s string) string { return Map(unicode.ToTitle, s) }
-
-// ToUpperSpecial returns a copy of the string s with all Unicode letters mapped to their
-// upper case using the case mapping specified by c.
-func ToUpperSpecial(c unicode.SpecialCase, s string) string {
-	return Map(c.ToUpper, s)
-}
-
-// ToLowerSpecial returns a copy of the string s with all Unicode letters mapped to their
-// lower case using the case mapping specified by c.
-func ToLowerSpecial(c unicode.SpecialCase, s string) string {
-	return Map(c.ToLower, s)
-}
-
-// ToTitleSpecial returns a copy of the string s with all Unicode letters mapped to their
-// Unicode title case, giving priority to the special casing rules.
-func ToTitleSpecial(c unicode.SpecialCase, s string) string {
-	return Map(c.ToTitle, s)
-}
-
-// ToValidUTF8 returns a copy of the string s with each run of invalid UTF-8 byte sequences
-// replaced by the replacement string, which may be empty.
-func ToValidUTF8(s, replacement string) string {
-	var b Builder
-
-	for i, c := range s {
-		if c != utf8.RuneError {
-			continue
-		}
-
-		_, wid := utf8.DecodeRuneInString(s[i:])
-		if wid == 1 {
-			b.Grow(len(s) + len(replacement))
-			b.WriteString(s[:i])
-			s = s[i:]
-			break
-		}
-	}
-
-	// Fast path for unchanged input
-	if b.Cap() == 0 { // didn't call b.Grow above
-		return s
-	}
-
-	invalid := false // previous byte was from an invalid UTF-8 sequence
-	for i := 0; i < len(s); {
-		c := s[i]
-		if c < utf8.RuneSelf {
-			i++
-			invalid = false
-			b.WriteByte(c)
-			continue
-		}
-		_, wid := utf8.DecodeRuneInString(s[i:])
-		if wid == 1 {
-			i++
-			if !invalid {
-				invalid = true
-				b.WriteString(replacement)
-			}
-			continue
-		}
-		invalid = false
-		b.WriteString(s[i : i+wid])
-		i += wid
-	}
-
-	return b.String()
-}
-
-// isSeparator reports whether the rune could mark a word boundary.
-// TODO: update when package unicode captures more of the properties.
-func isSeparator(r rune) bool {
-	// ASCII alphanumerics and underscore are not separators
-	if r <= 0x7F {
-		switch {
-		case '0' <= r && r <= '9':
-			return false
-		case 'a' <= r && r <= 'z':
-			return false
-		case 'A' <= r && r <= 'Z':
-			return false
-		case r == '_':
-			return false
-		}
-		return true
-	}
-	// Letters and digits are not separators
-	if unicode.IsLetter(r) || unicode.IsDigit(r) {
-		return false
-	}
-	// Otherwise, all we can do for now is treat spaces as separators.
-	return unicode.IsSpace(r)
-}
-
-// Title returns a copy of the string s with all Unicode letters that begin words
-// mapped to their Unicode title case.
-//
-// Deprecated: The rule Title uses for word boundaries does not handle Unicode
-// punctuation properly. Use golang.org/x/text/cases instead.
-func Title(s string) string {
-	// Use a closure here to remember state.
-	// Hackish but effective. Depends on Map scanning in order and calling
-	// the closure once per rune.
-	prev := ' '
-	return Map(
-		func(r rune) rune {
-			if isSeparator(prev) {
-				prev = r
-				return unicode.ToTitle(r)
-			}
-			prev = r
-			return r
-		},
-		s)
-}
-
-// TrimLeftFunc returns a slice of the string s with all leading
-// Unicode code points c satisfying f(c) removed.
-func TrimLeftFunc(s string, f func(rune) bool) string {
-	i := indexFunc(s, f, false)
-	if i == -1 {
-		return ""
-	}
-	return s[i:]
-}
-
-// TrimRightFunc returns a slice of the string s with all trailing
-// Unicode code points c satisfying f(c) removed.
-func TrimRightFunc(s string, f func(rune) bool) string {
-	i := lastIndexFunc(s, f, false)
-	if i >= 0 && s[i] >= utf8.RuneSelf {
-		_, wid := utf8.DecodeRuneInString(s[i:])
-		i += wid
-	} else {
-		i++
-	}
-	return s[0:i]
-}
-
-// TrimFunc returns a slice of the string s with all leading
-// and trailing Unicode code points c satisfying f(c) removed.
-func TrimFunc(s string, f func(rune) bool) string {
-	return TrimRightFunc(TrimLeftFunc(s, f), f)
-}
-
-// IndexFunc returns the index into s of the first Unicode
-// code point satisfying f(c), or -1 if none do.
-func IndexFunc(s string, f func(rune) bool) int {
-	return indexFunc(s, f, true)
-}
-
-// LastIndexFunc returns the index into s of the last
-// Unicode code point satisfying f(c), or -1 if none do.
-func LastIndexFunc(s string, f func(rune) bool) int {
-	return lastIndexFunc(s, f, true)
-}
-
-// indexFunc is the same as IndexFunc except that if
-// truth==false, the sense of the predicate function is
-// inverted.
-func indexFunc(s string, f func(rune) bool, truth bool) int {
-	for i, r := range s {
-		if f(r) == truth {
-			return i
-		}
-	}
-	return -1
-}
-
-// lastIndexFunc is the same as LastIndexFunc except that if
-// truth==false, the sense of the predicate function is
-// inverted.
-func lastIndexFunc(s string, f func(rune) bool, truth bool) int {
-	for i := len(s); i > 0; {
-		r, size := utf8.DecodeLastRuneInString(s[0:i])
-		i -= size
-		if f(r) == truth {
-			return i
-		}
-	}
-	return -1
-}
-
-// asciiSet is a 32-byte value, where each bit represents the presence of a
-// given ASCII character in the set. The 128-bits of the lower 16 bytes,
-// starting with the least-significant bit of the lowest word to the
-// most-significant bit of the highest word, map to the full range of all
-// 128 ASCII characters. The 128-bits of the upper 16 bytes will be zeroed,
-// ensuring that any non-ASCII character will be reported as not in the set.
-// This allocates a total of 32 bytes even though the upper half
-// is unused to avoid bounds checks in asciiSet.contains.
-type asciiSet [8]uint32
-
-// makeASCIISet creates a set of ASCII characters and reports whether all
-// characters in chars are ASCII.
-func makeASCIISet(chars string) (as asciiSet, ok bool) {
-	for i := 0; i < len(chars); i++ {
-		c := chars[i]
-		if c >= utf8.RuneSelf {
-			return as, false
-		}
-		as[c/32] |= 1 << (c % 32)
-	}
-	return as, true
-}
-
-// contains reports whether c is inside the set.
-func (as *asciiSet) contains(c byte) bool {
-	return (as[c/32] & (1 << (c % 32))) != 0
-}
-
-// Trim returns a slice of the string s with all leading and
-// trailing Unicode code points contained in cutset removed.
-func Trim(s, cutset string) string {
-	if s == "" || cutset == "" {
-		return s
-	}
-	if len(cutset) == 1 && cutset[0] < utf8.RuneSelf {
-		return trimLeftByte(trimRightByte(s, cutset[0]), cutset[0])
-	}
-	if as, ok := makeASCIISet(cutset); ok {
-		return trimLeftASCII(trimRightASCII(s, &as), &as)
-	}
-	return trimLeftUnicode(trimRightUnicode(s, cutset), cutset)
-}
-
-// TrimLeft returns a slice of the string s with all leading
-// Unicode code points contained in cutset removed.
-//
-// To remove a prefix, use TrimPrefix instead.
-func TrimLeft(s, cutset string) string {
-	if s == "" || cutset == "" {
-		return s
-	}
-	if len(cutset) == 1 && cutset[0] < utf8.RuneSelf {
-		return trimLeftByte(s, cutset[0])
-	}
-	if as, ok := makeASCIISet(cutset); ok {
-		return trimLeftASCII(s, &as)
-	}
-	return trimLeftUnicode(s, cutset)
-}
-
-func trimLeftByte(s string, c byte) string {
-	for len(s) > 0 && s[0] == c {
-		s = s[1:]
-	}
-	return s
-}
-
-func trimLeftASCII(s string, as *asciiSet) string {
-	for len(s) > 0 {
-		if !as.contains(s[0]) {
-			break
-		}
-		s = s[1:]
-	}
-	return s
-}
-
-func trimLeftUnicode(s, cutset string) string {
-	for len(s) > 0 {
-		r, n := rune(s[0]), 1
-		if r >= utf8.RuneSelf {
-			r, n = utf8.DecodeRuneInString(s)
-		}
-		if !ContainsRune(cutset, r) {
-			break
-		}
-		s = s[n:]
-	}
-	return s
-}
-
-// TrimRight returns a slice of the string s, with all trailing
-// Unicode code points contained in cutset removed.
-//
-// To remove a suffix, use TrimSuffix instead.
-func TrimRight(s, cutset string) string {
-	if s == "" || cutset == "" {
-		return s
-	}
-	if len(cutset) == 1 && cutset[0] < utf8.RuneSelf {
-		return trimRightByte(s, cutset[0])
-	}
-	if as, ok := makeASCIISet(cutset); ok {
-		return trimRightASCII(s, &as)
-	}
-	return trimRightUnicode(s, cutset)
-}
-
-func trimRightByte(s string, c byte) string {
-	for len(s) > 0 && s[len(s)-1] == c {
-		s = s[:len(s)-1]
-	}
-	return s
-}
-
-func trimRightASCII(s string, as *asciiSet) string {
-	for len(s) > 0 {
-		if !as.contains(s[len(s)-1]) {
-			break
-		}
-		s = s[:len(s)-1]
-	}
-	return s
-}
-
-func trimRightUnicode(s, cutset string) string {
-	for len(s) > 0 {
-		r, n := rune(s[len(s)-1]), 1
-		if r >= utf8.RuneSelf {
-			r, n = utf8.DecodeLastRuneInString(s)
-		}
-		if !ContainsRune(cutset, r) {
-			break
-		}
-		s = s[:len(s)-n]
-	}
-	return s
-}
-
-// TrimSpace returns a slice of the string s, with all leading
-// and trailing white space removed, as defined by Unicode.
-func TrimSpace(s string) string {
-	// Fast path for ASCII: look for the first ASCII non-space byte
-	start := 0
-	for ; start < len(s); start++ {
-		c := s[start]
-		if c >= utf8.RuneSelf {
-			// If we run into a non-ASCII byte, fall back to the
-			// slower unicode-aware method on the remaining bytes
-			return TrimFunc(s[start:], unicode.IsSpace)
-		}
-		if asciiSpace[c] == 0 {
-			break
-		}
-	}
-
-	// Now look for the first ASCII non-space byte from the end
-	stop := len(s)
-	for ; stop > start; stop-- {
-		c := s[stop-1]
-		if c >= utf8.RuneSelf {
-			return TrimFunc(s[start:stop], unicode.IsSpace)
-		}
-		if asciiSpace[c] == 0 {
-			break
-		}
-	}
-
-	// At this point s[start:stop] starts and ends with an ASCII
-	// non-space bytes, so we're done. Non-ASCII cases have already
-	// been handled above.
-	return s[start:stop]
-}
-
-// TrimPrefix returns s without the provided leading prefix string.
-// If s doesn't start with prefix, s is returned unchanged.
-func TrimPrefix(s, prefix string) string {
-	if HasPrefix(s, prefix) {
-		return s[len(prefix):]
-	}
-	return s
-}
-
-// TrimSuffix returns s without the provided trailing suffix string.
-// If s doesn't end with suffix, s is returned unchanged.
-func TrimSuffix(s, suffix string) string {
-	if HasSuffix(s, suffix) {
-		return s[:len(s)-len(suffix)]
-	}
-	return s
-}
-
-// Replace returns a copy of the string s with the first n
-// non-overlapping instances of old replaced by new.
-// If old is empty, it matches at the beginning of the string
-// and after each UTF-8 sequence, yielding up to k+1 replacements
-// for a k-rune string.
-// If n < 0, there is no limit on the number of replacements.
-func Replace(s, old, new string, n int) string {
-	if old == new || n == 0 {
-		return s // avoid allocation
-	}
-
-	// Compute number of replacements.
-	if m := Count(s, old); m == 0 {
-		return s // avoid allocation
-	} else if n < 0 || m < n {
-		n = m
-	}
-
-	// Apply replacements to buffer.
-	var b Builder
-	b.Grow(len(s) + n*(len(new)-len(old)))
-	start := 0
-	for i := 0; i < n; i++ {
-		j := start
-		if len(old) == 0 {
-			if i > 0 {
-				_, wid := utf8.DecodeRuneInString(s[start:])
-				j += wid
-			}
-		} else {
-			j += Index(s[start:], old)
-		}
-		b.WriteString(s[start:j])
-		b.WriteString(new)
-		start = j + len(old)
-	}
-	b.WriteString(s[start:])
-	return b.String()
-}
-
-// ReplaceAll returns a copy of the string s with all
-// non-overlapping instances of old replaced by new.
-// If old is empty, it matches at the beginning of the string
-// and after each UTF-8 sequence, yielding up to k+1 replacements
-// for a k-rune string.
-func ReplaceAll(s, old, new string) string {
-	return Replace(s, old, new, -1)
-}
-
-// EqualFold reports whether s and t, interpreted as UTF-8 strings,
-// are equal under Unicode case-folding, which is a more general
-// form of case-insensitivity.
-func EqualFold(s, t string) bool {
-	for s != "" && t != "" {
-		// Extract first rune from each string.
-		var sr, tr rune
-		if s[0] < utf8.RuneSelf {
-			sr, s = rune(s[0]), s[1:]
-		} else {
-			r, size := utf8.DecodeRuneInString(s)
-			sr, s = r, s[size:]
-		}
-		if t[0] < utf8.RuneSelf {
-			tr, t = rune(t[0]), t[1:]
-		} else {
-			r, size := utf8.DecodeRuneInString(t)
-			tr, t = r, t[size:]
-		}
-
-		// If they match, keep going; if not, return false.
-
-		// Easy case.
-		if tr == sr {
-			continue
-		}
-
-		// Make sr < tr to simplify what follows.
-		if tr < sr {
-			tr, sr = sr, tr
-		}
-		// Fast check for ASCII.
-		if tr < utf8.RuneSelf {
-			// ASCII only, sr/tr must be upper/lower case
-			if 'A' <= sr && sr <= 'Z' && tr == sr+'a'-'A' {
-				continue
-			}
-			return false
-		}
-
-		// General case. SimpleFold(x) returns the next equivalent rune > x
-		// or wraps around to smaller values.
-		r := unicode.SimpleFold(sr)
-		for r != sr && r < tr {
-			r = unicode.SimpleFold(r)
-		}
-		if r == tr {
-			continue
-		}
-		return false
-	}
-
-	// One string is empty. Are both?
-	return s == t
-}
-
-// Index returns the index of the first instance of substr in s, or -1 if substr is not present in s.
-func Index(s, substr string) int {
-	n := len(substr)
-	switch {
-	case n == 0:
-		return 0
-	case n == 1:
-		return IndexByte(s, substr[0])
-	case n == len(s):
-		if substr == s {
-			return 0
-		}
-		return -1
-	case n > len(s):
-		return -1
-	case n <= bytealg.MaxLen:
-		// Use brute force when s and substr both are small
-		if len(s) <= bytealg.MaxBruteForce {
-			return bytealg.IndexString(s, substr)
-		}
-		c0 := substr[0]
-		c1 := substr[1]
-		i := 0
-		t := len(s) - n + 1
-		fails := 0
-		for i < t {
-			if s[i] != c0 {
-				// IndexByte is faster than bytealg.IndexString, so use it as long as
-				// we're not getting lots of false positives.
-				o := IndexByte(s[i+1:t], c0)
-				if o < 0 {
-					return -1
-				}
-				i += o + 1
-			}
-			if s[i+1] == c1 && s[i:i+n] == substr {
-				return i
-			}
-			fails++
-			i++
-			// Switch to bytealg.IndexString when IndexByte produces too many false positives.
-			if fails > bytealg.Cutover(i) {
-				r := bytealg.IndexString(s[i:], substr)
-				if r >= 0 {
-					return r + i
-				}
-				return -1
-			}
-		}
-		return -1
-	}
-	c0 := substr[0]
-	c1 := substr[1]
-	i := 0
-	t := len(s) - n + 1
-	fails := 0
-	for i < t {
-		if s[i] != c0 {
-			o := IndexByte(s[i+1:t], c0)
-			if o < 0 {
-				return -1
-			}
-			i += o + 1
-		}
-		if s[i+1] == c1 && s[i:i+n] == substr {
-			return i
-		}
-		i++
-		fails++
-		if fails >= 4+i>>4 && i < t {
-			// See comment in ../bytes/bytes.go.
-			j := bytealg.IndexRabinKarp(s[i:], substr)
-			if j < 0 {
-				return -1
-			}
-			return i + j
-		}
-	}
-	return -1
-}
-
-// Cut slices s around the first instance of sep,
-// returning the text before and after sep.
-// The found result reports whether sep appears in s.
-// If sep does not appear in s, cut returns s, "", false.
-func Cut(s, sep string) (before, after string, found bool) {
-	if i := Index(s, sep); i >= 0 {
-		return s[:i], s[i+len(sep):], true
-	}
-	return s, "", false
-}
diff --git a/contrib/go/_std_1.18/src/sync/atomic/doc.go b/contrib/go/_std_1.18/src/sync/atomic/doc.go
deleted file mode 100644
index 805ef956d5..0000000000
--- a/contrib/go/_std_1.18/src/sync/atomic/doc.go
+++ /dev/null
@@ -1,144 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package atomic provides low-level atomic memory primitives
-// useful for implementing synchronization algorithms.
-//
-// These functions require great care to be used correctly.
-// Except for special, low-level applications, synchronization is better
-// done with channels or the facilities of the sync package.
-// Share memory by communicating;
-// don't communicate by sharing memory.
-//
-// The swap operation, implemented by the SwapT functions, is the atomic
-// equivalent of:
-//
-//	old = *addr
-//	*addr = new
-//	return old
-//
-// The compare-and-swap operation, implemented by the CompareAndSwapT
-// functions, is the atomic equivalent of:
-//
-//	if *addr == old {
-//		*addr = new
-//		return true
-//	}
-//	return false
-//
-// The add operation, implemented by the AddT functions, is the atomic
-// equivalent of:
-//
-//	*addr += delta
-//	return *addr
-//
-// The load and store operations, implemented by the LoadT and StoreT
-// functions, are the atomic equivalents of "return *addr" and
-// "*addr = val".
-//
-package atomic
-
-import (
-	"unsafe"
-)
-
-// BUG(rsc): On 386, the 64-bit functions use instructions unavailable before the Pentium MMX.
-//
-// On non-Linux ARM, the 64-bit functions use instructions unavailable before the ARMv6k core.
-//
-// On ARM, 386, and 32-bit MIPS, it is the caller's responsibility
-// to arrange for 64-bit alignment of 64-bit words accessed atomically.
-// The first word in a variable or in an allocated struct, array, or slice can
-// be relied upon to be 64-bit aligned.
-
-// SwapInt32 atomically stores new into *addr and returns the previous *addr value.
-func SwapInt32(addr *int32, new int32) (old int32)
-
-// SwapInt64 atomically stores new into *addr and returns the previous *addr value.
-func SwapInt64(addr *int64, new int64) (old int64)
-
-// SwapUint32 atomically stores new into *addr and returns the previous *addr value.
-func SwapUint32(addr *uint32, new uint32) (old uint32)
-
-// SwapUint64 atomically stores new into *addr and returns the previous *addr value.
-func SwapUint64(addr *uint64, new uint64) (old uint64)
-
-// SwapUintptr atomically stores new into *addr and returns the previous *addr value.
-func SwapUintptr(addr *uintptr, new uintptr) (old uintptr)
-
-// SwapPointer atomically stores new into *addr and returns the previous *addr value.
-func SwapPointer(addr *unsafe.Pointer, new unsafe.Pointer) (old unsafe.Pointer)
-
-// CompareAndSwapInt32 executes the compare-and-swap operation for an int32 value.
-func CompareAndSwapInt32(addr *int32, old, new int32) (swapped bool)
-
-// CompareAndSwapInt64 executes the compare-and-swap operation for an int64 value.
-func CompareAndSwapInt64(addr *int64, old, new int64) (swapped bool)
-
-// CompareAndSwapUint32 executes the compare-and-swap operation for a uint32 value.
-func CompareAndSwapUint32(addr *uint32, old, new uint32) (swapped bool)
-
-// CompareAndSwapUint64 executes the compare-and-swap operation for a uint64 value.
-func CompareAndSwapUint64(addr *uint64, old, new uint64) (swapped bool)
-
-// CompareAndSwapUintptr executes the compare-and-swap operation for a uintptr value.
-func CompareAndSwapUintptr(addr *uintptr, old, new uintptr) (swapped bool)
-
-// CompareAndSwapPointer executes the compare-and-swap operation for a unsafe.Pointer value.
-func CompareAndSwapPointer(addr *unsafe.Pointer, old, new unsafe.Pointer) (swapped bool)
-
-// AddInt32 atomically adds delta to *addr and returns the new value.
-func AddInt32(addr *int32, delta int32) (new int32)
-
-// AddUint32 atomically adds delta to *addr and returns the new value.
-// To subtract a signed positive constant value c from x, do AddUint32(&x, ^uint32(c-1)).
-// In particular, to decrement x, do AddUint32(&x, ^uint32(0)).
-func AddUint32(addr *uint32, delta uint32) (new uint32)
-
-// AddInt64 atomically adds delta to *addr and returns the new value.
-func AddInt64(addr *int64, delta int64) (new int64)
-
-// AddUint64 atomically adds delta to *addr and returns the new value.
-// To subtract a signed positive constant value c from x, do AddUint64(&x, ^uint64(c-1)).
-// In particular, to decrement x, do AddUint64(&x, ^uint64(0)).
-func AddUint64(addr *uint64, delta uint64) (new uint64)
-
-// AddUintptr atomically adds delta to *addr and returns the new value.
-func AddUintptr(addr *uintptr, delta uintptr) (new uintptr)
-
-// LoadInt32 atomically loads *addr.
-func LoadInt32(addr *int32) (val int32)
-
-// LoadInt64 atomically loads *addr.
-func LoadInt64(addr *int64) (val int64)
-
-// LoadUint32 atomically loads *addr.
-func LoadUint32(addr *uint32) (val uint32)
-
-// LoadUint64 atomically loads *addr.
-func LoadUint64(addr *uint64) (val uint64)
-
-// LoadUintptr atomically loads *addr.
-func LoadUintptr(addr *uintptr) (val uintptr)
-
-// LoadPointer atomically loads *addr.
-func LoadPointer(addr *unsafe.Pointer) (val unsafe.Pointer)
-
-// StoreInt32 atomically stores val into *addr.
-func StoreInt32(addr *int32, val int32)
-
-// StoreInt64 atomically stores val into *addr.
-func StoreInt64(addr *int64, val int64)
-
-// StoreUint32 atomically stores val into *addr.
-func StoreUint32(addr *uint32, val uint32)
-
-// StoreUint64 atomically stores val into *addr.
-func StoreUint64(addr *uint64, val uint64)
-
-// StoreUintptr atomically stores val into *addr.
-func StoreUintptr(addr *uintptr, val uintptr)
-
-// StorePointer atomically stores val into *addr.
-func StorePointer(addr *unsafe.Pointer, val unsafe.Pointer)
diff --git a/contrib/go/_std_1.18/src/sync/cond.go b/contrib/go/_std_1.18/src/sync/cond.go
deleted file mode 100644
index b254c9360a..0000000000
--- a/contrib/go/_std_1.18/src/sync/cond.go
+++ /dev/null
@@ -1,98 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package sync
-
-import (
-	"sync/atomic"
-	"unsafe"
-)
-
-// Cond implements a condition variable, a rendezvous point
-// for goroutines waiting for or announcing the occurrence
-// of an event.
-//
-// Each Cond has an associated Locker L (often a *Mutex or *RWMutex),
-// which must be held when changing the condition and
-// when calling the Wait method.
-//
-// A Cond must not be copied after first use.
-type Cond struct {
-	noCopy noCopy
-
-	// L is held while observing or changing the condition
-	L Locker
-
-	notify  notifyList
-	checker copyChecker
-}
-
-// NewCond returns a new Cond with Locker l.
-func NewCond(l Locker) *Cond {
-	return &Cond{L: l}
-}
-
-// Wait atomically unlocks c.L and suspends execution
-// of the calling goroutine. After later resuming execution,
-// Wait locks c.L before returning. Unlike in other systems,
-// Wait cannot return unless awoken by Broadcast or Signal.
-//
-// Because c.L is not locked when Wait first resumes, the caller
-// typically cannot assume that the condition is true when
-// Wait returns. Instead, the caller should Wait in a loop:
-//
-//    c.L.Lock()
-//    for !condition() {
-//        c.Wait()
-//    }
-//    ... make use of condition ...
-//    c.L.Unlock()
-//
-func (c *Cond) Wait() {
-	c.checker.check()
-	t := runtime_notifyListAdd(&c.notify)
-	c.L.Unlock()
-	runtime_notifyListWait(&c.notify, t)
-	c.L.Lock()
-}
-
-// Signal wakes one goroutine waiting on c, if there is any.
-//
-// It is allowed but not required for the caller to hold c.L
-// during the call.
-func (c *Cond) Signal() {
-	c.checker.check()
-	runtime_notifyListNotifyOne(&c.notify)
-}
-
-// Broadcast wakes all goroutines waiting on c.
-//
-// It is allowed but not required for the caller to hold c.L
-// during the call.
-func (c *Cond) Broadcast() {
-	c.checker.check()
-	runtime_notifyListNotifyAll(&c.notify)
-}
-
-// copyChecker holds back pointer to itself to detect object copying.
-type copyChecker uintptr
-
-func (c *copyChecker) check() {
-	if uintptr(*c) != uintptr(unsafe.Pointer(c)) &&
-		!atomic.CompareAndSwapUintptr((*uintptr)(c), 0, uintptr(unsafe.Pointer(c))) &&
-		uintptr(*c) != uintptr(unsafe.Pointer(c)) {
-		panic("sync.Cond is copied")
-	}
-}
-
-// noCopy may be embedded into structs which must not be copied
-// after the first use.
-//
-// See https://golang.org/issues/8005#issuecomment-190753527
-// for details.
-type noCopy struct{}
-
-// Lock is a no-op used by -copylocks checker from `go vet`.
-func (*noCopy) Lock()   {}
-func (*noCopy) Unlock() {}
diff --git a/contrib/go/_std_1.18/src/sync/map.go b/contrib/go/_std_1.18/src/sync/map.go
deleted file mode 100644
index 2fa3253429..0000000000
--- a/contrib/go/_std_1.18/src/sync/map.go
+++ /dev/null
@@ -1,386 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package sync
-
-import (
-	"sync/atomic"
-	"unsafe"
-)
-
-// Map is like a Go map[interface{}]interface{} but is safe for concurrent use
-// by multiple goroutines without additional locking or coordination.
-// Loads, stores, and deletes run in amortized constant time.
-//
-// The Map type is specialized. Most code should use a plain Go map instead,
-// with separate locking or coordination, for better type safety and to make it
-// easier to maintain other invariants along with the map content.
-//
-// The Map type is optimized for two common use cases: (1) when the entry for a given
-// key is only ever written once but read many times, as in caches that only grow,
-// or (2) when multiple goroutines read, write, and overwrite entries for disjoint
-// sets of keys. In these two cases, use of a Map may significantly reduce lock
-// contention compared to a Go map paired with a separate Mutex or RWMutex.
-//
-// The zero Map is empty and ready for use. A Map must not be copied after first use.
-type Map struct {
-	mu Mutex
-
-	// read contains the portion of the map's contents that are safe for
-	// concurrent access (with or without mu held).
-	//
-	// The read field itself is always safe to load, but must only be stored with
-	// mu held.
-	//
-	// Entries stored in read may be updated concurrently without mu, but updating
-	// a previously-expunged entry requires that the entry be copied to the dirty
-	// map and unexpunged with mu held.
-	read atomic.Value // readOnly
-
-	// dirty contains the portion of the map's contents that require mu to be
-	// held. To ensure that the dirty map can be promoted to the read map quickly,
-	// it also includes all of the non-expunged entries in the read map.
-	//
-	// Expunged entries are not stored in the dirty map. An expunged entry in the
-	// clean map must be unexpunged and added to the dirty map before a new value
-	// can be stored to it.
-	//
-	// If the dirty map is nil, the next write to the map will initialize it by
-	// making a shallow copy of the clean map, omitting stale entries.
-	dirty map[any]*entry
-
-	// misses counts the number of loads since the read map was last updated that
-	// needed to lock mu to determine whether the key was present.
-	//
-	// Once enough misses have occurred to cover the cost of copying the dirty
-	// map, the dirty map will be promoted to the read map (in the unamended
-	// state) and the next store to the map will make a new dirty copy.
-	misses int
-}
-
-// readOnly is an immutable struct stored atomically in the Map.read field.
-type readOnly struct {
-	m       map[any]*entry
-	amended bool // true if the dirty map contains some key not in m.
-}
-
-// expunged is an arbitrary pointer that marks entries which have been deleted
-// from the dirty map.
-var expunged = unsafe.Pointer(new(any))
-
-// An entry is a slot in the map corresponding to a particular key.
-type entry struct {
-	// p points to the interface{} value stored for the entry.
-	//
-	// If p == nil, the entry has been deleted, and either m.dirty == nil or
-	// m.dirty[key] is e.
-	//
-	// If p == expunged, the entry has been deleted, m.dirty != nil, and the entry
-	// is missing from m.dirty.
-	//
-	// Otherwise, the entry is valid and recorded in m.read.m[key] and, if m.dirty
-	// != nil, in m.dirty[key].
-	//
-	// An entry can be deleted by atomic replacement with nil: when m.dirty is
-	// next created, it will atomically replace nil with expunged and leave
-	// m.dirty[key] unset.
-	//
-	// An entry's associated value can be updated by atomic replacement, provided
-	// p != expunged. If p == expunged, an entry's associated value can be updated
-	// only after first setting m.dirty[key] = e so that lookups using the dirty
-	// map find the entry.
-	p unsafe.Pointer // *interface{}
-}
-
-func newEntry(i any) *entry {
-	return &entry{p: unsafe.Pointer(&i)}
-}
-
-// Load returns the value stored in the map for a key, or nil if no
-// value is present.
-// The ok result indicates whether value was found in the map.
-func (m *Map) Load(key any) (value any, ok bool) {
-	read, _ := m.read.Load().(readOnly)
-	e, ok := read.m[key]
-	if !ok && read.amended {
-		m.mu.Lock()
-		// Avoid reporting a spurious miss if m.dirty got promoted while we were
-		// blocked on m.mu. (If further loads of the same key will not miss, it's
-		// not worth copying the dirty map for this key.)
-		read, _ = m.read.Load().(readOnly)
-		e, ok = read.m[key]
-		if !ok && read.amended {
-			e, ok = m.dirty[key]
-			// Regardless of whether the entry was present, record a miss: this key
-			// will take the slow path until the dirty map is promoted to the read
-			// map.
-			m.missLocked()
-		}
-		m.mu.Unlock()
-	}
-	if !ok {
-		return nil, false
-	}
-	return e.load()
-}
-
-func (e *entry) load() (value any, ok bool) {
-	p := atomic.LoadPointer(&e.p)
-	if p == nil || p == expunged {
-		return nil, false
-	}
-	return *(*any)(p), true
-}
-
-// Store sets the value for a key.
-func (m *Map) Store(key, value any) {
-	read, _ := m.read.Load().(readOnly)
-	if e, ok := read.m[key]; ok && e.tryStore(&value) {
-		return
-	}
-
-	m.mu.Lock()
-	read, _ = m.read.Load().(readOnly)
-	if e, ok := read.m[key]; ok {
-		if e.unexpungeLocked() {
-			// The entry was previously expunged, which implies that there is a
-			// non-nil dirty map and this entry is not in it.
-			m.dirty[key] = e
-		}
-		e.storeLocked(&value)
-	} else if e, ok := m.dirty[key]; ok {
-		e.storeLocked(&value)
-	} else {
-		if !read.amended {
-			// We're adding the first new key to the dirty map.
-			// Make sure it is allocated and mark the read-only map as incomplete.
-			m.dirtyLocked()
-			m.read.Store(readOnly{m: read.m, amended: true})
-		}
-		m.dirty[key] = newEntry(value)
-	}
-	m.mu.Unlock()
-}
-
-// tryStore stores a value if the entry has not been expunged.
-//
-// If the entry is expunged, tryStore returns false and leaves the entry
-// unchanged.
-func (e *entry) tryStore(i *any) bool {
-	for {
-		p := atomic.LoadPointer(&e.p)
-		if p == expunged {
-			return false
-		}
-		if atomic.CompareAndSwapPointer(&e.p, p, unsafe.Pointer(i)) {
-			return true
-		}
-	}
-}
-
-// unexpungeLocked ensures that the entry is not marked as expunged.
-//
-// If the entry was previously expunged, it must be added to the dirty map
-// before m.mu is unlocked.
-func (e *entry) unexpungeLocked() (wasExpunged bool) {
-	return atomic.CompareAndSwapPointer(&e.p, expunged, nil)
-}
-
-// storeLocked unconditionally stores a value to the entry.
-//
-// The entry must be known not to be expunged.
-func (e *entry) storeLocked(i *any) {
-	atomic.StorePointer(&e.p, unsafe.Pointer(i))
-}
-
-// LoadOrStore returns the existing value for the key if present.
-// Otherwise, it stores and returns the given value.
-// The loaded result is true if the value was loaded, false if stored.
-func (m *Map) LoadOrStore(key, value any) (actual any, loaded bool) {
-	// Avoid locking if it's a clean hit.
-	read, _ := m.read.Load().(readOnly)
-	if e, ok := read.m[key]; ok {
-		actual, loaded, ok := e.tryLoadOrStore(value)
-		if ok {
-			return actual, loaded
-		}
-	}
-
-	m.mu.Lock()
-	read, _ = m.read.Load().(readOnly)
-	if e, ok := read.m[key]; ok {
-		if e.unexpungeLocked() {
-			m.dirty[key] = e
-		}
-		actual, loaded, _ = e.tryLoadOrStore(value)
-	} else if e, ok := m.dirty[key]; ok {
-		actual, loaded, _ = e.tryLoadOrStore(value)
-		m.missLocked()
-	} else {
-		if !read.amended {
-			// We're adding the first new key to the dirty map.
-			// Make sure it is allocated and mark the read-only map as incomplete.
-			m.dirtyLocked()
-			m.read.Store(readOnly{m: read.m, amended: true})
-		}
-		m.dirty[key] = newEntry(value)
-		actual, loaded = value, false
-	}
-	m.mu.Unlock()
-
-	return actual, loaded
-}
-
-// tryLoadOrStore atomically loads or stores a value if the entry is not
-// expunged.
-//
-// If the entry is expunged, tryLoadOrStore leaves the entry unchanged and
-// returns with ok==false.
-func (e *entry) tryLoadOrStore(i any) (actual any, loaded, ok bool) {
-	p := atomic.LoadPointer(&e.p)
-	if p == expunged {
-		return nil, false, false
-	}
-	if p != nil {
-		return *(*any)(p), true, true
-	}
-
-	// Copy the interface after the first load to make this method more amenable
-	// to escape analysis: if we hit the "load" path or the entry is expunged, we
-	// shouldn't bother heap-allocating.
-	ic := i
-	for {
-		if atomic.CompareAndSwapPointer(&e.p, nil, unsafe.Pointer(&ic)) {
-			return i, false, true
-		}
-		p = atomic.LoadPointer(&e.p)
-		if p == expunged {
-			return nil, false, false
-		}
-		if p != nil {
-			return *(*any)(p), true, true
-		}
-	}
-}
-
-// LoadAndDelete deletes the value for a key, returning the previous value if any.
-// The loaded result reports whether the key was present.
-func (m *Map) LoadAndDelete(key any) (value any, loaded bool) {
-	read, _ := m.read.Load().(readOnly)
-	e, ok := read.m[key]
-	if !ok && read.amended {
-		m.mu.Lock()
-		read, _ = m.read.Load().(readOnly)
-		e, ok = read.m[key]
-		if !ok && read.amended {
-			e, ok = m.dirty[key]
-			delete(m.dirty, key)
-			// Regardless of whether the entry was present, record a miss: this key
-			// will take the slow path until the dirty map is promoted to the read
-			// map.
-			m.missLocked()
-		}
-		m.mu.Unlock()
-	}
-	if ok {
-		return e.delete()
-	}
-	return nil, false
-}
-
-// Delete deletes the value for a key.
-func (m *Map) Delete(key any) {
-	m.LoadAndDelete(key)
-}
-
-func (e *entry) delete() (value any, ok bool) {
-	for {
-		p := atomic.LoadPointer(&e.p)
-		if p == nil || p == expunged {
-			return nil, false
-		}
-		if atomic.CompareAndSwapPointer(&e.p, p, nil) {
-			return *(*any)(p), true
-		}
-	}
-}
-
-// Range calls f sequentially for each key and value present in the map.
-// If f returns false, range stops the iteration.
-//
-// Range does not necessarily correspond to any consistent snapshot of the Map's
-// contents: no key will be visited more than once, but if the value for any key
-// is stored or deleted concurrently (including by f), Range may reflect any
-// mapping for that key from any point during the Range call. Range does not
-// block other methods on the receiver; even f itself may call any method on m.
-//
-// Range may be O(N) with the number of elements in the map even if f returns
-// false after a constant number of calls.
-func (m *Map) Range(f func(key, value any) bool) {
-	// We need to be able to iterate over all of the keys that were already
-	// present at the start of the call to Range.
-	// If read.amended is false, then read.m satisfies that property without
-	// requiring us to hold m.mu for a long time.
-	read, _ := m.read.Load().(readOnly)
-	if read.amended {
-		// m.dirty contains keys not in read.m. Fortunately, Range is already O(N)
-		// (assuming the caller does not break out early), so a call to Range
-		// amortizes an entire copy of the map: we can promote the dirty copy
-		// immediately!
-		m.mu.Lock()
-		read, _ = m.read.Load().(readOnly)
-		if read.amended {
-			read = readOnly{m: m.dirty}
-			m.read.Store(read)
-			m.dirty = nil
-			m.misses = 0
-		}
-		m.mu.Unlock()
-	}
-
-	for k, e := range read.m {
-		v, ok := e.load()
-		if !ok {
-			continue
-		}
-		if !f(k, v) {
-			break
-		}
-	}
-}
-
-func (m *Map) missLocked() {
-	m.misses++
-	if m.misses < len(m.dirty) {
-		return
-	}
-	m.read.Store(readOnly{m: m.dirty})
-	m.dirty = nil
-	m.misses = 0
-}
-
-func (m *Map) dirtyLocked() {
-	if m.dirty != nil {
-		return
-	}
-
-	read, _ := m.read.Load().(readOnly)
-	m.dirty = make(map[any]*entry, len(read.m))
-	for k, e := range read.m {
-		if !e.tryExpungeLocked() {
-			m.dirty[k] = e
-		}
-	}
-}
-
-func (e *entry) tryExpungeLocked() (isExpunged bool) {
-	p := atomic.LoadPointer(&e.p)
-	for p == nil {
-		if atomic.CompareAndSwapPointer(&e.p, nil, expunged) {
-			return true
-		}
-		p = atomic.LoadPointer(&e.p)
-	}
-	return p == expunged
-}
diff --git a/contrib/go/_std_1.18/src/sync/mutex.go b/contrib/go/_std_1.18/src/sync/mutex.go
deleted file mode 100644
index 18b2cedba7..0000000000
--- a/contrib/go/_std_1.18/src/sync/mutex.go
+++ /dev/null
@@ -1,250 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package sync provides basic synchronization primitives such as mutual
-// exclusion locks. Other than the Once and WaitGroup types, most are intended
-// for use by low-level library routines. Higher-level synchronization is
-// better done via channels and communication.
-//
-// Values containing the types defined in this package should not be copied.
-package sync
-
-import (
-	"internal/race"
-	"sync/atomic"
-	"unsafe"
-)
-
-func throw(string) // provided by runtime
-
-// A Mutex is a mutual exclusion lock.
-// The zero value for a Mutex is an unlocked mutex.
-//
-// A Mutex must not be copied after first use.
-type Mutex struct {
-	state int32
-	sema  uint32
-}
-
-// A Locker represents an object that can be locked and unlocked.
-type Locker interface {
-	Lock()
-	Unlock()
-}
-
-const (
-	mutexLocked = 1 << iota // mutex is locked
-	mutexWoken
-	mutexStarving
-	mutexWaiterShift = iota
-
-	// Mutex fairness.
-	//
-	// Mutex can be in 2 modes of operations: normal and starvation.
-	// In normal mode waiters are queued in FIFO order, but a woken up waiter
-	// does not own the mutex and competes with new arriving goroutines over
-	// the ownership. New arriving goroutines have an advantage -- they are
-	// already running on CPU and there can be lots of them, so a woken up
-	// waiter has good chances of losing. In such case it is queued at front
-	// of the wait queue. If a waiter fails to acquire the mutex for more than 1ms,
-	// it switches mutex to the starvation mode.
-	//
-	// In starvation mode ownership of the mutex is directly handed off from
-	// the unlocking goroutine to the waiter at the front of the queue.
-	// New arriving goroutines don't try to acquire the mutex even if it appears
-	// to be unlocked, and don't try to spin. Instead they queue themselves at
-	// the tail of the wait queue.
-	//
-	// If a waiter receives ownership of the mutex and sees that either
-	// (1) it is the last waiter in the queue, or (2) it waited for less than 1 ms,
-	// it switches mutex back to normal operation mode.
-	//
-	// Normal mode has considerably better performance as a goroutine can acquire
-	// a mutex several times in a row even if there are blocked waiters.
-	// Starvation mode is important to prevent pathological cases of tail latency.
-	starvationThresholdNs = 1e6
-)
-
-// Lock locks m.
-// If the lock is already in use, the calling goroutine
-// blocks until the mutex is available.
-func (m *Mutex) Lock() {
-	// Fast path: grab unlocked mutex.
-	if atomic.CompareAndSwapInt32(&m.state, 0, mutexLocked) {
-		if race.Enabled {
-			race.Acquire(unsafe.Pointer(m))
-		}
-		return
-	}
-	// Slow path (outlined so that the fast path can be inlined)
-	m.lockSlow()
-}
-
-// TryLock tries to lock m and reports whether it succeeded.
-//
-// Note that while correct uses of TryLock do exist, they are rare,
-// and use of TryLock is often a sign of a deeper problem
-// in a particular use of mutexes.
-func (m *Mutex) TryLock() bool {
-	old := m.state
-	if old&(mutexLocked|mutexStarving) != 0 {
-		return false
-	}
-
-	// There may be a goroutine waiting for the mutex, but we are
-	// running now and can try to grab the mutex before that
-	// goroutine wakes up.
-	if !atomic.CompareAndSwapInt32(&m.state, old, old|mutexLocked) {
-		return false
-	}
-
-	if race.Enabled {
-		race.Acquire(unsafe.Pointer(m))
-	}
-	return true
-}
-
-func (m *Mutex) lockSlow() {
-	var waitStartTime int64
-	starving := false
-	awoke := false
-	iter := 0
-	old := m.state
-	for {
-		// Don't spin in starvation mode, ownership is handed off to waiters
-		// so we won't be able to acquire the mutex anyway.
-		if old&(mutexLocked|mutexStarving) == mutexLocked && runtime_canSpin(iter) {
-			// Active spinning makes sense.
-			// Try to set mutexWoken flag to inform Unlock
-			// to not wake other blocked goroutines.
-			if !awoke && old&mutexWoken == 0 && old>>mutexWaiterShift != 0 &&
-				atomic.CompareAndSwapInt32(&m.state, old, old|mutexWoken) {
-				awoke = true
-			}
-			runtime_doSpin()
-			iter++
-			old = m.state
-			continue
-		}
-		new := old
-		// Don't try to acquire starving mutex, new arriving goroutines must queue.
-		if old&mutexStarving == 0 {
-			new |= mutexLocked
-		}
-		if old&(mutexLocked|mutexStarving) != 0 {
-			new += 1 << mutexWaiterShift
-		}
-		// The current goroutine switches mutex to starvation mode.
-		// But if the mutex is currently unlocked, don't do the switch.
-		// Unlock expects that starving mutex has waiters, which will not
-		// be true in this case.
-		if starving && old&mutexLocked != 0 {
-			new |= mutexStarving
-		}
-		if awoke {
-			// The goroutine has been woken from sleep,
-			// so we need to reset the flag in either case.
-			if new&mutexWoken == 0 {
-				throw("sync: inconsistent mutex state")
-			}
-			new &^= mutexWoken
-		}
-		if atomic.CompareAndSwapInt32(&m.state, old, new) {
-			if old&(mutexLocked|mutexStarving) == 0 {
-				break // locked the mutex with CAS
-			}
-			// If we were already waiting before, queue at the front of the queue.
-			queueLifo := waitStartTime != 0
-			if waitStartTime == 0 {
-				waitStartTime = runtime_nanotime()
-			}
-			runtime_SemacquireMutex(&m.sema, queueLifo, 1)
-			starving = starving || runtime_nanotime()-waitStartTime > starvationThresholdNs
-			old = m.state
-			if old&mutexStarving != 0 {
-				// If this goroutine was woken and mutex is in starvation mode,
-				// ownership was handed off to us but mutex is in somewhat
-				// inconsistent state: mutexLocked is not set and we are still
-				// accounted as waiter. Fix that.
-				if old&(mutexLocked|mutexWoken) != 0 || old>>mutexWaiterShift == 0 {
-					throw("sync: inconsistent mutex state")
-				}
-				delta := int32(mutexLocked - 1<<mutexWaiterShift)
-				if !starving || old>>mutexWaiterShift == 1 {
-					// Exit starvation mode.
-					// Critical to do it here and consider wait time.
-					// Starvation mode is so inefficient, that two goroutines
-					// can go lock-step infinitely once they switch mutex
-					// to starvation mode.
-					delta -= mutexStarving
-				}
-				atomic.AddInt32(&m.state, delta)
-				break
-			}
-			awoke = true
-			iter = 0
-		} else {
-			old = m.state
-		}
-	}
-
-	if race.Enabled {
-		race.Acquire(unsafe.Pointer(m))
-	}
-}
-
-// Unlock unlocks m.
-// It is a run-time error if m is not locked on entry to Unlock.
-//
-// A locked Mutex is not associated with a particular goroutine.
-// It is allowed for one goroutine to lock a Mutex and then
-// arrange for another goroutine to unlock it.
-func (m *Mutex) Unlock() {
-	if race.Enabled {
-		_ = m.state
-		race.Release(unsafe.Pointer(m))
-	}
-
-	// Fast path: drop lock bit.
-	new := atomic.AddInt32(&m.state, -mutexLocked)
-	if new != 0 {
-		// Outlined slow path to allow inlining the fast path.
-		// To hide unlockSlow during tracing we skip one extra frame when tracing GoUnblock.
-		m.unlockSlow(new)
-	}
-}
-
-func (m *Mutex) unlockSlow(new int32) {
-	if (new+mutexLocked)&mutexLocked == 0 {
-		throw("sync: unlock of unlocked mutex")
-	}
-	if new&mutexStarving == 0 {
-		old := new
-		for {
-			// If there are no waiters or a goroutine has already
-			// been woken or grabbed the lock, no need to wake anyone.
-			// In starvation mode ownership is directly handed off from unlocking
-			// goroutine to the next waiter. We are not part of this chain,
-			// since we did not observe mutexStarving when we unlocked the mutex above.
-			// So get off the way.
-			if old>>mutexWaiterShift == 0 || old&(mutexLocked|mutexWoken|mutexStarving) != 0 {
-				return
-			}
-			// Grab the right to wake someone.
-			new = (old - 1<<mutexWaiterShift) | mutexWoken
-			if atomic.CompareAndSwapInt32(&m.state, old, new) {
-				runtime_Semrelease(&m.sema, false, 1)
-				return
-			}
-			old = m.state
-		}
-	} else {
-		// Starving mode: handoff mutex ownership to the next waiter, and yield
-		// our time slice so that the next waiter can start to run immediately.
-		// Note: mutexLocked is not set, the waiter will set it after wakeup.
-		// But mutex is still considered locked if mutexStarving is set,
-		// so new coming goroutines won't acquire it.
-		runtime_Semrelease(&m.sema, true, 1)
-	}
-}
diff --git a/contrib/go/_std_1.18/src/sync/once.go b/contrib/go/_std_1.18/src/sync/once.go
deleted file mode 100644
index 8844314e7e..0000000000
--- a/contrib/go/_std_1.18/src/sync/once.go
+++ /dev/null
@@ -1,70 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package sync
-
-import (
-	"sync/atomic"
-)
-
-// Once is an object that will perform exactly one action.
-//
-// A Once must not be copied after first use.
-type Once struct {
-	// done indicates whether the action has been performed.
-	// It is first in the struct because it is used in the hot path.
-	// The hot path is inlined at every call site.
-	// Placing done first allows more compact instructions on some architectures (amd64/386),
-	// and fewer instructions (to calculate offset) on other architectures.
-	done uint32
-	m    Mutex
-}
-
-// Do calls the function f if and only if Do is being called for the
-// first time for this instance of Once. In other words, given
-// 	var once Once
-// if once.Do(f) is called multiple times, only the first call will invoke f,
-// even if f has a different value in each invocation. A new instance of
-// Once is required for each function to execute.
-//
-// Do is intended for initialization that must be run exactly once. Since f
-// is niladic, it may be necessary to use a function literal to capture the
-// arguments to a function to be invoked by Do:
-// 	config.once.Do(func() { config.init(filename) })
-//
-// Because no call to Do returns until the one call to f returns, if f causes
-// Do to be called, it will deadlock.
-//
-// If f panics, Do considers it to have returned; future calls of Do return
-// without calling f.
-//
-func (o *Once) Do(f func()) {
-	// Note: Here is an incorrect implementation of Do:
-	//
-	//	if atomic.CompareAndSwapUint32(&o.done, 0, 1) {
-	//		f()
-	//	}
-	//
-	// Do guarantees that when it returns, f has finished.
-	// This implementation would not implement that guarantee:
-	// given two simultaneous calls, the winner of the cas would
-	// call f, and the second would return immediately, without
-	// waiting for the first's call to f to complete.
-	// This is why the slow path falls back to a mutex, and why
-	// the atomic.StoreUint32 must be delayed until after f returns.
-
-	if atomic.LoadUint32(&o.done) == 0 {
-		// Outlined slow-path to allow inlining of the fast-path.
-		o.doSlow(f)
-	}
-}
-
-func (o *Once) doSlow(f func()) {
-	o.m.Lock()
-	defer o.m.Unlock()
-	if o.done == 0 {
-		defer atomic.StoreUint32(&o.done, 1)
-		f()
-	}
-}
diff --git a/contrib/go/_std_1.18/src/sync/pool.go b/contrib/go/_std_1.18/src/sync/pool.go
deleted file mode 100644
index d1abb6a8b7..0000000000
--- a/contrib/go/_std_1.18/src/sync/pool.go
+++ /dev/null
@@ -1,294 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package sync
-
-import (
-	"internal/race"
-	"runtime"
-	"sync/atomic"
-	"unsafe"
-)
-
-// A Pool is a set of temporary objects that may be individually saved and
-// retrieved.
-//
-// Any item stored in the Pool may be removed automatically at any time without
-// notification. If the Pool holds the only reference when this happens, the
-// item might be deallocated.
-//
-// A Pool is safe for use by multiple goroutines simultaneously.
-//
-// Pool's purpose is to cache allocated but unused items for later reuse,
-// relieving pressure on the garbage collector. That is, it makes it easy to
-// build efficient, thread-safe free lists. However, it is not suitable for all
-// free lists.
-//
-// An appropriate use of a Pool is to manage a group of temporary items
-// silently shared among and potentially reused by concurrent independent
-// clients of a package. Pool provides a way to amortize allocation overhead
-// across many clients.
-//
-// An example of good use of a Pool is in the fmt package, which maintains a
-// dynamically-sized store of temporary output buffers. The store scales under
-// load (when many goroutines are actively printing) and shrinks when
-// quiescent.
-//
-// On the other hand, a free list maintained as part of a short-lived object is
-// not a suitable use for a Pool, since the overhead does not amortize well in
-// that scenario. It is more efficient to have such objects implement their own
-// free list.
-//
-// A Pool must not be copied after first use.
-type Pool struct {
-	noCopy noCopy
-
-	local     unsafe.Pointer // local fixed-size per-P pool, actual type is [P]poolLocal
-	localSize uintptr        // size of the local array
-
-	victim     unsafe.Pointer // local from previous cycle
-	victimSize uintptr        // size of victims array
-
-	// New optionally specifies a function to generate
-	// a value when Get would otherwise return nil.
-	// It may not be changed concurrently with calls to Get.
-	New func() any
-}
-
-// Local per-P Pool appendix.
-type poolLocalInternal struct {
-	private any       // Can be used only by the respective P.
-	shared  poolChain // Local P can pushHead/popHead; any P can popTail.
-}
-
-type poolLocal struct {
-	poolLocalInternal
-
-	// Prevents false sharing on widespread platforms with
-	// 128 mod (cache line size) = 0 .
-	pad [128 - unsafe.Sizeof(poolLocalInternal{})%128]byte
-}
-
-// from runtime
-func fastrandn(n uint32) uint32
-
-var poolRaceHash [128]uint64
-
-// poolRaceAddr returns an address to use as the synchronization point
-// for race detector logic. We don't use the actual pointer stored in x
-// directly, for fear of conflicting with other synchronization on that address.
-// Instead, we hash the pointer to get an index into poolRaceHash.
-// See discussion on golang.org/cl/31589.
-func poolRaceAddr(x any) unsafe.Pointer {
-	ptr := uintptr((*[2]unsafe.Pointer)(unsafe.Pointer(&x))[1])
-	h := uint32((uint64(uint32(ptr)) * 0x85ebca6b) >> 16)
-	return unsafe.Pointer(&poolRaceHash[h%uint32(len(poolRaceHash))])
-}
-
-// Put adds x to the pool.
-func (p *Pool) Put(x any) {
-	if x == nil {
-		return
-	}
-	if race.Enabled {
-		if fastrandn(4) == 0 {
-			// Randomly drop x on floor.
-			return
-		}
-		race.ReleaseMerge(poolRaceAddr(x))
-		race.Disable()
-	}
-	l, _ := p.pin()
-	if l.private == nil {
-		l.private = x
-		x = nil
-	}
-	if x != nil {
-		l.shared.pushHead(x)
-	}
-	runtime_procUnpin()
-	if race.Enabled {
-		race.Enable()
-	}
-}
-
-// Get selects an arbitrary item from the Pool, removes it from the
-// Pool, and returns it to the caller.
-// Get may choose to ignore the pool and treat it as empty.
-// Callers should not assume any relation between values passed to Put and
-// the values returned by Get.
-//
-// If Get would otherwise return nil and p.New is non-nil, Get returns
-// the result of calling p.New.
-func (p *Pool) Get() any {
-	if race.Enabled {
-		race.Disable()
-	}
-	l, pid := p.pin()
-	x := l.private
-	l.private = nil
-	if x == nil {
-		// Try to pop the head of the local shard. We prefer
-		// the head over the tail for temporal locality of
-		// reuse.
-		x, _ = l.shared.popHead()
-		if x == nil {
-			x = p.getSlow(pid)
-		}
-	}
-	runtime_procUnpin()
-	if race.Enabled {
-		race.Enable()
-		if x != nil {
-			race.Acquire(poolRaceAddr(x))
-		}
-	}
-	if x == nil && p.New != nil {
-		x = p.New()
-	}
-	return x
-}
-
-func (p *Pool) getSlow(pid int) any {
-	// See the comment in pin regarding ordering of the loads.
-	size := runtime_LoadAcquintptr(&p.localSize) // load-acquire
-	locals := p.local                            // load-consume
-	// Try to steal one element from other procs.
-	for i := 0; i < int(size); i++ {
-		l := indexLocal(locals, (pid+i+1)%int(size))
-		if x, _ := l.shared.popTail(); x != nil {
-			return x
-		}
-	}
-
-	// Try the victim cache. We do this after attempting to steal
-	// from all primary caches because we want objects in the
-	// victim cache to age out if at all possible.
-	size = atomic.LoadUintptr(&p.victimSize)
-	if uintptr(pid) >= size {
-		return nil
-	}
-	locals = p.victim
-	l := indexLocal(locals, pid)
-	if x := l.private; x != nil {
-		l.private = nil
-		return x
-	}
-	for i := 0; i < int(size); i++ {
-		l := indexLocal(locals, (pid+i)%int(size))
-		if x, _ := l.shared.popTail(); x != nil {
-			return x
-		}
-	}
-
-	// Mark the victim cache as empty for future gets don't bother
-	// with it.
-	atomic.StoreUintptr(&p.victimSize, 0)
-
-	return nil
-}
-
-// pin pins the current goroutine to P, disables preemption and
-// returns poolLocal pool for the P and the P's id.
-// Caller must call runtime_procUnpin() when done with the pool.
-func (p *Pool) pin() (*poolLocal, int) {
-	pid := runtime_procPin()
-	// In pinSlow we store to local and then to localSize, here we load in opposite order.
-	// Since we've disabled preemption, GC cannot happen in between.
-	// Thus here we must observe local at least as large localSize.
-	// We can observe a newer/larger local, it is fine (we must observe its zero-initialized-ness).
-	s := runtime_LoadAcquintptr(&p.localSize) // load-acquire
-	l := p.local                              // load-consume
-	if uintptr(pid) < s {
-		return indexLocal(l, pid), pid
-	}
-	return p.pinSlow()
-}
-
-func (p *Pool) pinSlow() (*poolLocal, int) {
-	// Retry under the mutex.
-	// Can not lock the mutex while pinned.
-	runtime_procUnpin()
-	allPoolsMu.Lock()
-	defer allPoolsMu.Unlock()
-	pid := runtime_procPin()
-	// poolCleanup won't be called while we are pinned.
-	s := p.localSize
-	l := p.local
-	if uintptr(pid) < s {
-		return indexLocal(l, pid), pid
-	}
-	if p.local == nil {
-		allPools = append(allPools, p)
-	}
-	// If GOMAXPROCS changes between GCs, we re-allocate the array and lose the old one.
-	size := runtime.GOMAXPROCS(0)
-	local := make([]poolLocal, size)
-	atomic.StorePointer(&p.local, unsafe.Pointer(&local[0])) // store-release
-	runtime_StoreReluintptr(&p.localSize, uintptr(size))     // store-release
-	return &local[pid], pid
-}
-
-func poolCleanup() {
-	// This function is called with the world stopped, at the beginning of a garbage collection.
-	// It must not allocate and probably should not call any runtime functions.
-
-	// Because the world is stopped, no pool user can be in a
-	// pinned section (in effect, this has all Ps pinned).
-
-	// Drop victim caches from all pools.
-	for _, p := range oldPools {
-		p.victim = nil
-		p.victimSize = 0
-	}
-
-	// Move primary cache to victim cache.
-	for _, p := range allPools {
-		p.victim = p.local
-		p.victimSize = p.localSize
-		p.local = nil
-		p.localSize = 0
-	}
-
-	// The pools with non-empty primary caches now have non-empty
-	// victim caches and no pools have primary caches.
-	oldPools, allPools = allPools, nil
-}
-
-var (
-	allPoolsMu Mutex
-
-	// allPools is the set of pools that have non-empty primary
-	// caches. Protected by either 1) allPoolsMu and pinning or 2)
-	// STW.
-	allPools []*Pool
-
-	// oldPools is the set of pools that may have non-empty victim
-	// caches. Protected by STW.
-	oldPools []*Pool
-)
-
-func init() {
-	runtime_registerPoolCleanup(poolCleanup)
-}
-
-func indexLocal(l unsafe.Pointer, i int) *poolLocal {
-	lp := unsafe.Pointer(uintptr(l) + uintptr(i)*unsafe.Sizeof(poolLocal{}))
-	return (*poolLocal)(lp)
-}
-
-// Implemented in runtime.
-func runtime_registerPoolCleanup(cleanup func())
-func runtime_procPin() int
-func runtime_procUnpin()
-
-// The below are implemented in runtime/internal/atomic and the
-// compiler also knows to intrinsify the symbol we linkname into this
-// package.
-
-//go:linkname runtime_LoadAcquintptr runtime/internal/atomic.LoadAcquintptr
-func runtime_LoadAcquintptr(ptr *uintptr) uintptr
-
-//go:linkname runtime_StoreReluintptr runtime/internal/atomic.StoreReluintptr
-func runtime_StoreReluintptr(ptr *uintptr, val uintptr) uintptr
diff --git a/contrib/go/_std_1.18/src/sync/rwmutex.go b/contrib/go/_std_1.18/src/sync/rwmutex.go
deleted file mode 100644
index f0d4c9771a..0000000000
--- a/contrib/go/_std_1.18/src/sync/rwmutex.go
+++ /dev/null
@@ -1,223 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package sync
-
-import (
-	"internal/race"
-	"sync/atomic"
-	"unsafe"
-)
-
-// There is a modified copy of this file in runtime/rwmutex.go.
-// If you make any changes here, see if you should make them there.
-
-// A RWMutex is a reader/writer mutual exclusion lock.
-// The lock can be held by an arbitrary number of readers or a single writer.
-// The zero value for a RWMutex is an unlocked mutex.
-//
-// A RWMutex must not be copied after first use.
-//
-// If a goroutine holds a RWMutex for reading and another goroutine might
-// call Lock, no goroutine should expect to be able to acquire a read lock
-// until the initial read lock is released. In particular, this prohibits
-// recursive read locking. This is to ensure that the lock eventually becomes
-// available; a blocked Lock call excludes new readers from acquiring the
-// lock.
-type RWMutex struct {
-	w           Mutex  // held if there are pending writers
-	writerSem   uint32 // semaphore for writers to wait for completing readers
-	readerSem   uint32 // semaphore for readers to wait for completing writers
-	readerCount int32  // number of pending readers
-	readerWait  int32  // number of departing readers
-}
-
-const rwmutexMaxReaders = 1 << 30
-
-// Happens-before relationships are indicated to the race detector via:
-// - Unlock  -> Lock:  readerSem
-// - Unlock  -> RLock: readerSem
-// - RUnlock -> Lock:  writerSem
-//
-// The methods below temporarily disable handling of race synchronization
-// events in order to provide the more precise model above to the race
-// detector.
-//
-// For example, atomic.AddInt32 in RLock should not appear to provide
-// acquire-release semantics, which would incorrectly synchronize racing
-// readers, thus potentially missing races.
-
-// RLock locks rw for reading.
-//
-// It should not be used for recursive read locking; a blocked Lock
-// call excludes new readers from acquiring the lock. See the
-// documentation on the RWMutex type.
-func (rw *RWMutex) RLock() {
-	if race.Enabled {
-		_ = rw.w.state
-		race.Disable()
-	}
-	if atomic.AddInt32(&rw.readerCount, 1) < 0 {
-		// A writer is pending, wait for it.
-		runtime_SemacquireMutex(&rw.readerSem, false, 0)
-	}
-	if race.Enabled {
-		race.Enable()
-		race.Acquire(unsafe.Pointer(&rw.readerSem))
-	}
-}
-
-// TryRLock tries to lock rw for reading and reports whether it succeeded.
-//
-// Note that while correct uses of TryRLock do exist, they are rare,
-// and use of TryRLock is often a sign of a deeper problem
-// in a particular use of mutexes.
-func (rw *RWMutex) TryRLock() bool {
-	if race.Enabled {
-		_ = rw.w.state
-		race.Disable()
-	}
-	for {
-		c := atomic.LoadInt32(&rw.readerCount)
-		if c < 0 {
-			if race.Enabled {
-				race.Enable()
-			}
-			return false
-		}
-		if atomic.CompareAndSwapInt32(&rw.readerCount, c, c+1) {
-			if race.Enabled {
-				race.Enable()
-				race.Acquire(unsafe.Pointer(&rw.readerSem))
-			}
-			return true
-		}
-	}
-}
-
-// RUnlock undoes a single RLock call;
-// it does not affect other simultaneous readers.
-// It is a run-time error if rw is not locked for reading
-// on entry to RUnlock.
-func (rw *RWMutex) RUnlock() {
-	if race.Enabled {
-		_ = rw.w.state
-		race.ReleaseMerge(unsafe.Pointer(&rw.writerSem))
-		race.Disable()
-	}
-	if r := atomic.AddInt32(&rw.readerCount, -1); r < 0 {
-		// Outlined slow-path to allow the fast-path to be inlined
-		rw.rUnlockSlow(r)
-	}
-	if race.Enabled {
-		race.Enable()
-	}
-}
-
-func (rw *RWMutex) rUnlockSlow(r int32) {
-	if r+1 == 0 || r+1 == -rwmutexMaxReaders {
-		race.Enable()
-		throw("sync: RUnlock of unlocked RWMutex")
-	}
-	// A writer is pending.
-	if atomic.AddInt32(&rw.readerWait, -1) == 0 {
-		// The last reader unblocks the writer.
-		runtime_Semrelease(&rw.writerSem, false, 1)
-	}
-}
-
-// Lock locks rw for writing.
-// If the lock is already locked for reading or writing,
-// Lock blocks until the lock is available.
-func (rw *RWMutex) Lock() {
-	if race.Enabled {
-		_ = rw.w.state
-		race.Disable()
-	}
-	// First, resolve competition with other writers.
-	rw.w.Lock()
-	// Announce to readers there is a pending writer.
-	r := atomic.AddInt32(&rw.readerCount, -rwmutexMaxReaders) + rwmutexMaxReaders
-	// Wait for active readers.
-	if r != 0 && atomic.AddInt32(&rw.readerWait, r) != 0 {
-		runtime_SemacquireMutex(&rw.writerSem, false, 0)
-	}
-	if race.Enabled {
-		race.Enable()
-		race.Acquire(unsafe.Pointer(&rw.readerSem))
-		race.Acquire(unsafe.Pointer(&rw.writerSem))
-	}
-}
-
-// TryLock tries to lock rw for writing and reports whether it succeeded.
-//
-// Note that while correct uses of TryLock do exist, they are rare,
-// and use of TryLock is often a sign of a deeper problem
-// in a particular use of mutexes.
-func (rw *RWMutex) TryLock() bool {
-	if race.Enabled {
-		_ = rw.w.state
-		race.Disable()
-	}
-	if !rw.w.TryLock() {
-		if race.Enabled {
-			race.Enable()
-		}
-		return false
-	}
-	if !atomic.CompareAndSwapInt32(&rw.readerCount, 0, -rwmutexMaxReaders) {
-		rw.w.Unlock()
-		if race.Enabled {
-			race.Enable()
-		}
-		return false
-	}
-	if race.Enabled {
-		race.Enable()
-		race.Acquire(unsafe.Pointer(&rw.readerSem))
-		race.Acquire(unsafe.Pointer(&rw.writerSem))
-	}
-	return true
-}
-
-// Unlock unlocks rw for writing. It is a run-time error if rw is
-// not locked for writing on entry to Unlock.
-//
-// As with Mutexes, a locked RWMutex is not associated with a particular
-// goroutine. One goroutine may RLock (Lock) a RWMutex and then
-// arrange for another goroutine to RUnlock (Unlock) it.
-func (rw *RWMutex) Unlock() {
-	if race.Enabled {
-		_ = rw.w.state
-		race.Release(unsafe.Pointer(&rw.readerSem))
-		race.Disable()
-	}
-
-	// Announce to readers there is no active writer.
-	r := atomic.AddInt32(&rw.readerCount, rwmutexMaxReaders)
-	if r >= rwmutexMaxReaders {
-		race.Enable()
-		throw("sync: Unlock of unlocked RWMutex")
-	}
-	// Unblock blocked readers, if any.
-	for i := 0; i < int(r); i++ {
-		runtime_Semrelease(&rw.readerSem, false, 0)
-	}
-	// Allow other writers to proceed.
-	rw.w.Unlock()
-	if race.Enabled {
-		race.Enable()
-	}
-}
-
-// RLocker returns a Locker interface that implements
-// the Lock and Unlock methods by calling rw.RLock and rw.RUnlock.
-func (rw *RWMutex) RLocker() Locker {
-	return (*rlocker)(rw)
-}
-
-type rlocker RWMutex
-
-func (r *rlocker) Lock()   { (*RWMutex)(r).RLock() }
-func (r *rlocker) Unlock() { (*RWMutex)(r).RUnlock() }
diff --git a/contrib/go/_std_1.18/src/sync/waitgroup.go b/contrib/go/_std_1.18/src/sync/waitgroup.go
deleted file mode 100644
index 9c6662d04b..0000000000
--- a/contrib/go/_std_1.18/src/sync/waitgroup.go
+++ /dev/null
@@ -1,147 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package sync
-
-import (
-	"internal/race"
-	"sync/atomic"
-	"unsafe"
-)
-
-// A WaitGroup waits for a collection of goroutines to finish.
-// The main goroutine calls Add to set the number of
-// goroutines to wait for. Then each of the goroutines
-// runs and calls Done when finished. At the same time,
-// Wait can be used to block until all goroutines have finished.
-//
-// A WaitGroup must not be copied after first use.
-type WaitGroup struct {
-	noCopy noCopy
-
-	// 64-bit value: high 32 bits are counter, low 32 bits are waiter count.
-	// 64-bit atomic operations require 64-bit alignment, but 32-bit
-	// compilers only guarantee that 64-bit fields are 32-bit aligned.
-	// For this reason on 32 bit architectures we need to check in state()
-	// if state1 is aligned or not, and dynamically "swap" the field order if
-	// needed.
-	state1 uint64
-	state2 uint32
-}
-
-// state returns pointers to the state and sema fields stored within wg.state*.
-func (wg *WaitGroup) state() (statep *uint64, semap *uint32) {
-	if unsafe.Alignof(wg.state1) == 8 || uintptr(unsafe.Pointer(&wg.state1))%8 == 0 {
-		// state1 is 64-bit aligned: nothing to do.
-		return &wg.state1, &wg.state2
-	} else {
-		// state1 is 32-bit aligned but not 64-bit aligned: this means that
-		// (&state1)+4 is 64-bit aligned.
-		state := (*[3]uint32)(unsafe.Pointer(&wg.state1))
-		return (*uint64)(unsafe.Pointer(&state[1])), &state[0]
-	}
-}
-
-// Add adds delta, which may be negative, to the WaitGroup counter.
-// If the counter becomes zero, all goroutines blocked on Wait are released.
-// If the counter goes negative, Add panics.
-//
-// Note that calls with a positive delta that occur when the counter is zero
-// must happen before a Wait. Calls with a negative delta, or calls with a
-// positive delta that start when the counter is greater than zero, may happen
-// at any time.
-// Typically this means the calls to Add should execute before the statement
-// creating the goroutine or other event to be waited for.
-// If a WaitGroup is reused to wait for several independent sets of events,
-// new Add calls must happen after all previous Wait calls have returned.
-// See the WaitGroup example.
-func (wg *WaitGroup) Add(delta int) {
-	statep, semap := wg.state()
-	if race.Enabled {
-		_ = *statep // trigger nil deref early
-		if delta < 0 {
-			// Synchronize decrements with Wait.
-			race.ReleaseMerge(unsafe.Pointer(wg))
-		}
-		race.Disable()
-		defer race.Enable()
-	}
-	state := atomic.AddUint64(statep, uint64(delta)<<32)
-	v := int32(state >> 32)
-	w := uint32(state)
-	if race.Enabled && delta > 0 && v == int32(delta) {
-		// The first increment must be synchronized with Wait.
-		// Need to model this as a read, because there can be
-		// several concurrent wg.counter transitions from 0.
-		race.Read(unsafe.Pointer(semap))
-	}
-	if v < 0 {
-		panic("sync: negative WaitGroup counter")
-	}
-	if w != 0 && delta > 0 && v == int32(delta) {
-		panic("sync: WaitGroup misuse: Add called concurrently with Wait")
-	}
-	if v > 0 || w == 0 {
-		return
-	}
-	// This goroutine has set counter to 0 when waiters > 0.
-	// Now there can't be concurrent mutations of state:
-	// - Adds must not happen concurrently with Wait,
-	// - Wait does not increment waiters if it sees counter == 0.
-	// Still do a cheap sanity check to detect WaitGroup misuse.
-	if *statep != state {
-		panic("sync: WaitGroup misuse: Add called concurrently with Wait")
-	}
-	// Reset waiters count to 0.
-	*statep = 0
-	for ; w != 0; w-- {
-		runtime_Semrelease(semap, false, 0)
-	}
-}
-
-// Done decrements the WaitGroup counter by one.
-func (wg *WaitGroup) Done() {
-	wg.Add(-1)
-}
-
-// Wait blocks until the WaitGroup counter is zero.
-func (wg *WaitGroup) Wait() {
-	statep, semap := wg.state()
-	if race.Enabled {
-		_ = *statep // trigger nil deref early
-		race.Disable()
-	}
-	for {
-		state := atomic.LoadUint64(statep)
-		v := int32(state >> 32)
-		w := uint32(state)
-		if v == 0 {
-			// Counter is 0, no need to wait.
-			if race.Enabled {
-				race.Enable()
-				race.Acquire(unsafe.Pointer(wg))
-			}
-			return
-		}
-		// Increment waiters count.
-		if atomic.CompareAndSwapUint64(statep, state, state+1) {
-			if race.Enabled && w == 0 {
-				// Wait must be synchronized with the first Add.
-				// Need to model this is as a write to race with the read in Add.
-				// As a consequence, can do the write only for the first waiter,
-				// otherwise concurrent Waits will race with each other.
-				race.Write(unsafe.Pointer(semap))
-			}
-			runtime_Semacquire(semap)
-			if *statep != 0 {
-				panic("sync: WaitGroup is reused before previous Wait has returned")
-			}
-			if race.Enabled {
-				race.Enable()
-				race.Acquire(unsafe.Pointer(wg))
-			}
-			return
-		}
-	}
-}
diff --git a/contrib/go/_std_1.18/src/syscall/asm_darwin_amd64.s b/contrib/go/_std_1.18/src/syscall/asm_darwin_amd64.s
deleted file mode 100644
index c863889a71..0000000000
--- a/contrib/go/_std_1.18/src/syscall/asm_darwin_amd64.s
+++ /dev/null
@@ -1,134 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-#include "textflag.h"
-#include "funcdata.h"
-
-//
-// System call support for AMD64, Darwin
-//
-
-// Trap # in AX, args in DI SI DX, return in AX DX
-
-// func Syscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno);
-TEXT	·Syscall(SB),NOSPLIT,$0-56
-	CALL	runtime·entersyscall(SB)
-	MOVQ	a1+8(FP), DI
-	MOVQ	a2+16(FP), SI
-	MOVQ	a3+24(FP), DX
-	MOVQ	trap+0(FP), AX	// syscall entry
-	ADDQ	$0x2000000, AX
-	SYSCALL
-	JCC	ok
-	MOVQ	$-1, r1+32(FP)
-	MOVQ	$0, r2+40(FP)
-	MOVQ	AX, err+48(FP)
-	CALL	runtime·exitsyscall(SB)
-	RET
-ok:
-	MOVQ	AX, r1+32(FP)
-	MOVQ	DX, r2+40(FP)
-	MOVQ	$0, err+48(FP)
-	CALL	runtime·exitsyscall(SB)
-	RET
-
-// func Syscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno);
-TEXT	·Syscall6(SB),NOSPLIT,$0-80
-	CALL	runtime·entersyscall(SB)
-	MOVQ	a1+8(FP), DI
-	MOVQ	a2+16(FP), SI
-	MOVQ	a3+24(FP), DX
-	MOVQ	a4+32(FP), R10
-	MOVQ	a5+40(FP), R8
-	MOVQ	a6+48(FP), R9
-	MOVQ	trap+0(FP), AX	// syscall entry
-	ADDQ	$0x2000000, AX
-	SYSCALL
-	JCC	ok6
-	MOVQ	$-1, r1+56(FP)
-	MOVQ	$0, r2+64(FP)
-	MOVQ	AX, err+72(FP)
-	CALL	runtime·exitsyscall(SB)
-	RET
-ok6:
-	MOVQ	AX, r1+56(FP)
-	MOVQ	DX, r2+64(FP)
-	MOVQ	$0, err+72(FP)
-	CALL	runtime·exitsyscall(SB)
-	RET
-
-// func Syscall9(trap, a1, a2, a3, a4, a5, a6, a7, a8, a9 uintptr) (r1, r2 uintptr, err Errno)
-TEXT	·Syscall9(SB),NOSPLIT,$0-104
-	CALL	runtime·entersyscall(SB)
-	MOVQ	trap+0(FP), AX	// syscall entry
-	MOVQ	a1+8(FP), DI
-	MOVQ	a2+16(FP), SI
-	MOVQ	a3+24(FP), DX
-	MOVQ	a4+32(FP), R10
-	MOVQ	a5+40(FP), R8
-	MOVQ	a6+48(FP), R9
-	MOVQ	a7+56(FP), R11
-	MOVQ	a8+64(FP), R12
-	MOVQ	a9+72(FP), R13
-	SUBQ	$32, SP
-	MOVQ	R11, 8(SP)
-	MOVQ	R12, 16(SP)
-	MOVQ	R13, 24(SP)
-	ADDQ	$0x2000000, AX
-	SYSCALL
-	JCC	ok9
-	ADDQ	$32, SP
-	MOVQ	$-1, r1+80(FP)
-	MOVQ	$0, r2+88(FP)
-	MOVQ	AX, err+96(FP)
-	CALL	runtime·exitsyscall(SB)
-	RET
-ok9:
-	ADDQ	$32, SP
-	MOVQ	AX, r1+80(FP)
-	MOVQ	DX, r2+88(FP)
-	MOVQ	$0, err+96(FP)
-	CALL	runtime·exitsyscall(SB)
-	RET
-
-// func RawSyscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno)
-TEXT ·RawSyscall(SB),NOSPLIT,$0-56
-	MOVQ	a1+8(FP), DI
-	MOVQ	a2+16(FP), SI
-	MOVQ	a3+24(FP), DX
-	MOVQ	trap+0(FP), AX	// syscall entry
-	ADDQ	$0x2000000, AX
-	SYSCALL
-	JCC	ok1
-	MOVQ	$-1, r1+32(FP)
-	MOVQ	$0, r2+40(FP)
-	MOVQ	AX, err+48(FP)
-	RET
-ok1:
-	MOVQ	AX, r1+32(FP)
-	MOVQ	DX, r2+40(FP)
-	MOVQ	$0, err+48(FP)
-	RET
-
-// func RawSyscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno)
-TEXT	·RawSyscall6(SB),NOSPLIT,$0-80
-	MOVQ	a1+8(FP), DI
-	MOVQ	a2+16(FP), SI
-	MOVQ	a3+24(FP), DX
-	MOVQ	a4+32(FP), R10
-	MOVQ	a5+40(FP), R8
-	MOVQ	a6+48(FP), R9
-	MOVQ	trap+0(FP), AX	// syscall entry
-	ADDQ	$0x2000000, AX
-	SYSCALL
-	JCC	ok2
-	MOVQ	$-1, r1+56(FP)
-	MOVQ	$0, r2+64(FP)
-	MOVQ	AX, err+72(FP)
-	RET
-ok2:
-	MOVQ	AX, r1+56(FP)
-	MOVQ	DX, r2+64(FP)
-	MOVQ	$0, err+72(FP)
-	RET
diff --git a/contrib/go/_std_1.18/src/syscall/asm_linux_amd64.s b/contrib/go/_std_1.18/src/syscall/asm_linux_amd64.s
deleted file mode 100644
index a9af68d51d..0000000000
--- a/contrib/go/_std_1.18/src/syscall/asm_linux_amd64.s
+++ /dev/null
@@ -1,164 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-#include "textflag.h"
-#include "funcdata.h"
-
-//
-// System calls for AMD64, Linux
-//
-
-#define SYS_gettimeofday 96
-
-// func Syscall(trap int64, a1, a2, a3 uintptr) (r1, r2, err uintptr);
-// Trap # in AX, args in DI SI DX R10 R8 R9, return in AX DX
-// Note that this differs from "standard" ABI convention, which
-// would pass 4th arg in CX, not R10.
-
-TEXT ·Syscall(SB),NOSPLIT,$0-56
-	CALL	runtime·entersyscall(SB)
-	MOVQ	a1+8(FP), DI
-	MOVQ	a2+16(FP), SI
-	MOVQ	a3+24(FP), DX
-	MOVQ	trap+0(FP), AX	// syscall entry
-	SYSCALL
-	CMPQ	AX, $0xfffffffffffff001
-	JLS	ok
-	MOVQ	$-1, r1+32(FP)
-	MOVQ	$0, r2+40(FP)
-	NEGQ	AX
-	MOVQ	AX, err+48(FP)
-	CALL	runtime·exitsyscall(SB)
-	RET
-ok:
-	MOVQ	AX, r1+32(FP)
-	MOVQ	DX, r2+40(FP)
-	MOVQ	$0, err+48(FP)
-	CALL	runtime·exitsyscall(SB)
-	RET
-
-// func Syscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr)
-TEXT ·Syscall6(SB),NOSPLIT,$0-80
-	CALL	runtime·entersyscall(SB)
-	MOVQ	a1+8(FP), DI
-	MOVQ	a2+16(FP), SI
-	MOVQ	a3+24(FP), DX
-	MOVQ	a4+32(FP), R10
-	MOVQ	a5+40(FP), R8
-	MOVQ	a6+48(FP), R9
-	MOVQ	trap+0(FP), AX	// syscall entry
-	SYSCALL
-	CMPQ	AX, $0xfffffffffffff001
-	JLS	ok6
-	MOVQ	$-1, r1+56(FP)
-	MOVQ	$0, r2+64(FP)
-	NEGQ	AX
-	MOVQ	AX, err+72(FP)
-	CALL	runtime·exitsyscall(SB)
-	RET
-ok6:
-	MOVQ	AX, r1+56(FP)
-	MOVQ	DX, r2+64(FP)
-	MOVQ	$0, err+72(FP)
-	CALL	runtime·exitsyscall(SB)
-	RET
-
-// func RawSyscall(trap, a1, a2, a3 uintptr) (r1, r2, err uintptr)
-TEXT ·RawSyscall(SB),NOSPLIT,$0-56
-	MOVQ	a1+8(FP), DI
-	MOVQ	a2+16(FP), SI
-	MOVQ	a3+24(FP), DX
-	MOVQ	trap+0(FP), AX	// syscall entry
-	SYSCALL
-	CMPQ	AX, $0xfffffffffffff001
-	JLS	ok1
-	MOVQ	$-1, r1+32(FP)
-	MOVQ	$0, r2+40(FP)
-	NEGQ	AX
-	MOVQ	AX, err+48(FP)
-	RET
-ok1:
-	MOVQ	AX, r1+32(FP)
-	MOVQ	DX, r2+40(FP)
-	MOVQ	$0, err+48(FP)
-	RET
-
-// func RawSyscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr)
-TEXT ·RawSyscall6(SB),NOSPLIT,$0-80
-	MOVQ	a1+8(FP), DI
-	MOVQ	a2+16(FP), SI
-	MOVQ	a3+24(FP), DX
-	MOVQ	a4+32(FP), R10
-	MOVQ	a5+40(FP), R8
-	MOVQ	a6+48(FP), R9
-	MOVQ	trap+0(FP), AX	// syscall entry
-	SYSCALL
-	CMPQ	AX, $0xfffffffffffff001
-	JLS	ok2
-	MOVQ	$-1, r1+56(FP)
-	MOVQ	$0, r2+64(FP)
-	NEGQ	AX
-	MOVQ	AX, err+72(FP)
-	RET
-ok2:
-	MOVQ	AX, r1+56(FP)
-	MOVQ	DX, r2+64(FP)
-	MOVQ	$0, err+72(FP)
-	RET
-
-// func rawVforkSyscall(trap, a1 uintptr) (r1, err uintptr)
-TEXT ·rawVforkSyscall(SB),NOSPLIT|NOFRAME,$0-32
-	MOVQ	a1+8(FP), DI
-	MOVQ	$0, SI
-	MOVQ	$0, DX
-	MOVQ	$0, R10
-	MOVQ	$0, R8
-	MOVQ	$0, R9
-	MOVQ	trap+0(FP), AX	// syscall entry
-	POPQ	R12 // preserve return address
-	SYSCALL
-	PUSHQ	R12
-	CMPQ	AX, $0xfffffffffffff001
-	JLS	ok2
-	MOVQ	$-1, r1+16(FP)
-	NEGQ	AX
-	MOVQ	AX, err+24(FP)
-	RET
-ok2:
-	MOVQ	AX, r1+16(FP)
-	MOVQ	$0, err+24(FP)
-	RET
-
-// func rawSyscallNoError(trap, a1, a2, a3 uintptr) (r1, r2 uintptr)
-TEXT ·rawSyscallNoError(SB),NOSPLIT,$0-48
-	MOVQ	a1+8(FP), DI
-	MOVQ	a2+16(FP), SI
-	MOVQ	a3+24(FP), DX
-	MOVQ	trap+0(FP), AX	// syscall entry
-	SYSCALL
-	MOVQ	AX, r1+32(FP)
-	MOVQ	DX, r2+40(FP)
-	RET
-
-// func gettimeofday(tv *Timeval) (err uintptr)
-TEXT ·gettimeofday(SB),NOSPLIT,$0-16
-	MOVQ	tv+0(FP), DI
-	MOVQ	$0, SI
-	MOVQ	runtime·vdsoGettimeofdaySym(SB), AX
-	TESTQ   AX, AX
-	JZ fallback
-	CALL	AX
-ret:
-	CMPQ	AX, $0xfffffffffffff001
-	JLS	ok7
-	NEGQ	AX
-	MOVQ	AX, err+8(FP)
-	RET
-fallback:
-	MOVL	$SYS_gettimeofday, AX
-	SYSCALL
-	JMP ret
-ok7:
-	MOVQ	$0, err+8(FP)
-	RET
diff --git a/contrib/go/_std_1.18/src/syscall/dirent.go b/contrib/go/_std_1.18/src/syscall/dirent.go
deleted file mode 100644
index 237ea79ad6..0000000000
--- a/contrib/go/_std_1.18/src/syscall/dirent.go
+++ /dev/null
@@ -1,102 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris
-
-package syscall
-
-import "unsafe"
-
-// readInt returns the size-bytes unsigned integer in native byte order at offset off.
-func readInt(b []byte, off, size uintptr) (u uint64, ok bool) {
-	if len(b) < int(off+size) {
-		return 0, false
-	}
-	if isBigEndian {
-		return readIntBE(b[off:], size), true
-	}
-	return readIntLE(b[off:], size), true
-}
-
-func readIntBE(b []byte, size uintptr) uint64 {
-	switch size {
-	case 1:
-		return uint64(b[0])
-	case 2:
-		_ = b[1] // bounds check hint to compiler; see golang.org/issue/14808
-		return uint64(b[1]) | uint64(b[0])<<8
-	case 4:
-		_ = b[3] // bounds check hint to compiler; see golang.org/issue/14808
-		return uint64(b[3]) | uint64(b[2])<<8 | uint64(b[1])<<16 | uint64(b[0])<<24
-	case 8:
-		_ = b[7] // bounds check hint to compiler; see golang.org/issue/14808
-		return uint64(b[7]) | uint64(b[6])<<8 | uint64(b[5])<<16 | uint64(b[4])<<24 |
-			uint64(b[3])<<32 | uint64(b[2])<<40 | uint64(b[1])<<48 | uint64(b[0])<<56
-	default:
-		panic("syscall: readInt with unsupported size")
-	}
-}
-
-func readIntLE(b []byte, size uintptr) uint64 {
-	switch size {
-	case 1:
-		return uint64(b[0])
-	case 2:
-		_ = b[1] // bounds check hint to compiler; see golang.org/issue/14808
-		return uint64(b[0]) | uint64(b[1])<<8
-	case 4:
-		_ = b[3] // bounds check hint to compiler; see golang.org/issue/14808
-		return uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24
-	case 8:
-		_ = b[7] // bounds check hint to compiler; see golang.org/issue/14808
-		return uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 |
-			uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56
-	default:
-		panic("syscall: readInt with unsupported size")
-	}
-}
-
-// ParseDirent parses up to max directory entries in buf,
-// appending the names to names. It returns the number of
-// bytes consumed from buf, the number of entries added
-// to names, and the new names slice.
-func ParseDirent(buf []byte, max int, names []string) (consumed int, count int, newnames []string) {
-	origlen := len(buf)
-	count = 0
-	for max != 0 && len(buf) > 0 {
-		reclen, ok := direntReclen(buf)
-		if !ok || reclen > uint64(len(buf)) {
-			return origlen, count, names
-		}
-		rec := buf[:reclen]
-		buf = buf[reclen:]
-		ino, ok := direntIno(rec)
-		if !ok {
-			break
-		}
-		if ino == 0 { // File absent in directory.
-			continue
-		}
-		const namoff = uint64(unsafe.Offsetof(Dirent{}.Name))
-		namlen, ok := direntNamlen(rec)
-		if !ok || namoff+namlen > uint64(len(rec)) {
-			break
-		}
-		name := rec[namoff : namoff+namlen]
-		for i, c := range name {
-			if c == 0 {
-				name = name[:i]
-				break
-			}
-		}
-		// Check for useless names before allocating a string.
-		if string(name) == "." || string(name) == ".." {
-			continue
-		}
-		max--
-		count++
-		names = append(names, string(name))
-	}
-	return origlen - len(buf), count, names
-}
diff --git a/contrib/go/_std_1.18/src/syscall/endian_little.go b/contrib/go/_std_1.18/src/syscall/endian_little.go
deleted file mode 100644
index edfb6cf164..0000000000
--- a/contrib/go/_std_1.18/src/syscall/endian_little.go
+++ /dev/null
@@ -1,9 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-//
-//go:build 386 || amd64 || arm || arm64 || ppc64le || mips64le || mipsle || riscv64 || wasm
-
-package syscall
-
-const isBigEndian = false
diff --git a/contrib/go/_std_1.18/src/syscall/env_unix.go b/contrib/go/_std_1.18/src/syscall/env_unix.go
deleted file mode 100644
index 521967c79f..0000000000
--- a/contrib/go/_std_1.18/src/syscall/env_unix.go
+++ /dev/null
@@ -1,155 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris || plan9
-
-// Unix environment variables.
-
-package syscall
-
-import (
-	"runtime"
-	"sync"
-)
-
-var (
-	// envOnce guards initialization by copyenv, which populates env.
-	envOnce sync.Once
-
-	// envLock guards env and envs.
-	envLock sync.RWMutex
-
-	// env maps from an environment variable to its first occurrence in envs.
-	env map[string]int
-
-	// envs is provided by the runtime. elements are expected to
-	// be of the form "key=value". An empty string means deleted
-	// (or a duplicate to be ignored).
-	envs []string = runtime_envs()
-)
-
-func runtime_envs() []string // in package runtime
-
-// setenv_c and unsetenv_c are provided by the runtime but are no-ops
-// if cgo isn't loaded.
-func setenv_c(k, v string)
-func unsetenv_c(k string)
-
-func copyenv() {
-	env = make(map[string]int)
-	for i, s := range envs {
-		for j := 0; j < len(s); j++ {
-			if s[j] == '=' {
-				key := s[:j]
-				if _, ok := env[key]; !ok {
-					env[key] = i // first mention of key
-				} else {
-					// Clear duplicate keys. This permits Unsetenv to
-					// safely delete only the first item without
-					// worrying about unshadowing a later one,
-					// which might be a security problem.
-					envs[i] = ""
-				}
-				break
-			}
-		}
-	}
-}
-
-func Unsetenv(key string) error {
-	envOnce.Do(copyenv)
-
-	envLock.Lock()
-	defer envLock.Unlock()
-
-	if i, ok := env[key]; ok {
-		envs[i] = ""
-		delete(env, key)
-	}
-	unsetenv_c(key)
-	return nil
-}
-
-func Getenv(key string) (value string, found bool) {
-	envOnce.Do(copyenv)
-	if len(key) == 0 {
-		return "", false
-	}
-
-	envLock.RLock()
-	defer envLock.RUnlock()
-
-	i, ok := env[key]
-	if !ok {
-		return "", false
-	}
-	s := envs[i]
-	for i := 0; i < len(s); i++ {
-		if s[i] == '=' {
-			return s[i+1:], true
-		}
-	}
-	return "", false
-}
-
-func Setenv(key, value string) error {
-	envOnce.Do(copyenv)
-	if len(key) == 0 {
-		return EINVAL
-	}
-	for i := 0; i < len(key); i++ {
-		if key[i] == '=' || key[i] == 0 {
-			return EINVAL
-		}
-	}
-	// On Plan 9, null is used as a separator, eg in $path.
-	if runtime.GOOS != "plan9" {
-		for i := 0; i < len(value); i++ {
-			if value[i] == 0 {
-				return EINVAL
-			}
-		}
-	}
-
-	envLock.Lock()
-	defer envLock.Unlock()
-
-	i, ok := env[key]
-	kv := key + "=" + value
-	if ok {
-		envs[i] = kv
-	} else {
-		i = len(envs)
-		envs = append(envs, kv)
-	}
-	env[key] = i
-	setenv_c(key, value)
-	return nil
-}
-
-func Clearenv() {
-	envOnce.Do(copyenv) // prevent copyenv in Getenv/Setenv
-
-	envLock.Lock()
-	defer envLock.Unlock()
-
-	for k := range env {
-		unsetenv_c(k)
-	}
-	env = make(map[string]int)
-	envs = []string{}
-}
-
-func Environ() []string {
-	envOnce.Do(copyenv)
-	envLock.RLock()
-	defer envLock.RUnlock()
-	a := make([]string, 0, len(envs))
-	for _, env := range envs {
-		if env != "" {
-			a = append(a, env)
-		}
-	}
-	return a
-}
diff --git a/contrib/go/_std_1.18/src/syscall/exec_libc2.go b/contrib/go/_std_1.18/src/syscall/exec_libc2.go
deleted file mode 100644
index b05f053bbf..0000000000
--- a/contrib/go/_std_1.18/src/syscall/exec_libc2.go
+++ /dev/null
@@ -1,265 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build darwin || (openbsd && !mips64)
-
-package syscall
-
-import (
-	"internal/abi"
-	"unsafe"
-)
-
-type SysProcAttr struct {
-	Chroot     string      // Chroot.
-	Credential *Credential // Credential.
-	Ptrace     bool        // Enable tracing.
-	Setsid     bool        // Create session.
-	// Setpgid sets the process group ID of the child to Pgid,
-	// or, if Pgid == 0, to the new child's process ID.
-	Setpgid bool
-	// Setctty sets the controlling terminal of the child to
-	// file descriptor Ctty. Ctty must be a descriptor number
-	// in the child process: an index into ProcAttr.Files.
-	// This is only meaningful if Setsid is true.
-	Setctty bool
-	Noctty  bool // Detach fd 0 from controlling terminal
-	Ctty    int  // Controlling TTY fd
-	// Foreground places the child process group in the foreground.
-	// This implies Setpgid. The Ctty field must be set to
-	// the descriptor of the controlling TTY.
-	// Unlike Setctty, in this case Ctty must be a descriptor
-	// number in the parent process.
-	Foreground bool
-	Pgid       int // Child's process group ID if Setpgid.
-}
-
-// Implemented in runtime package.
-func runtime_BeforeFork()
-func runtime_AfterFork()
-func runtime_AfterForkInChild()
-
-// Fork, dup fd onto 0..len(fd), and exec(argv0, argvv, envv) in child.
-// If a dup or exec fails, write the errno error to pipe.
-// (Pipe is close-on-exec so if exec succeeds, it will be closed.)
-// In the child, this function must not acquire any locks, because
-// they might have been locked at the time of the fork. This means
-// no rescheduling, no malloc calls, and no new stack segments.
-// For the same reason compiler does not race instrument it.
-// The calls to rawSyscall are okay because they are assembly
-// functions that do not grow the stack.
-//go:norace
-func forkAndExecInChild(argv0 *byte, argv, envv []*byte, chroot, dir *byte, attr *ProcAttr, sys *SysProcAttr, pipe int) (pid int, err Errno) {
-	// Declare all variables at top in case any
-	// declarations require heap allocation (e.g., err1).
-	var (
-		r1     uintptr
-		err1   Errno
-		nextfd int
-		i      int
-	)
-
-	// guard against side effects of shuffling fds below.
-	// Make sure that nextfd is beyond any currently open files so
-	// that we can't run the risk of overwriting any of them.
-	fd := make([]int, len(attr.Files))
-	nextfd = len(attr.Files)
-	for i, ufd := range attr.Files {
-		if nextfd < int(ufd) {
-			nextfd = int(ufd)
-		}
-		fd[i] = int(ufd)
-	}
-	nextfd++
-
-	// About to call fork.
-	// No more allocation or calls of non-assembly functions.
-	runtime_BeforeFork()
-	r1, _, err1 = rawSyscall(abi.FuncPCABI0(libc_fork_trampoline), 0, 0, 0)
-	if err1 != 0 {
-		runtime_AfterFork()
-		return 0, err1
-	}
-
-	if r1 != 0 {
-		// parent; return PID
-		runtime_AfterFork()
-		return int(r1), 0
-	}
-
-	// Fork succeeded, now in child.
-
-	// Enable tracing if requested.
-	if sys.Ptrace {
-		if err := ptrace(PTRACE_TRACEME, 0, 0, 0); err != nil {
-			err1 = err.(Errno)
-			goto childerror
-		}
-	}
-
-	// Session ID
-	if sys.Setsid {
-		_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_setsid_trampoline), 0, 0, 0)
-		if err1 != 0 {
-			goto childerror
-		}
-	}
-
-	// Set process group
-	if sys.Setpgid || sys.Foreground {
-		// Place child in process group.
-		_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_setpgid_trampoline), 0, uintptr(sys.Pgid), 0)
-		if err1 != 0 {
-			goto childerror
-		}
-	}
-
-	if sys.Foreground {
-		// This should really be pid_t, however _C_int (aka int32) is
-		// generally equivalent.
-		pgrp := _C_int(sys.Pgid)
-		if pgrp == 0 {
-			r1, _, err1 = rawSyscall(abi.FuncPCABI0(libc_getpid_trampoline), 0, 0, 0)
-			if err1 != 0 {
-				goto childerror
-			}
-			pgrp = _C_int(r1)
-		}
-
-		// Place process group in foreground.
-		_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_ioctl_trampoline), uintptr(sys.Ctty), uintptr(TIOCSPGRP), uintptr(unsafe.Pointer(&pgrp)))
-		if err1 != 0 {
-			goto childerror
-		}
-	}
-
-	// Restore the signal mask. We do this after TIOCSPGRP to avoid
-	// having the kernel send a SIGTTOU signal to the process group.
-	runtime_AfterForkInChild()
-
-	// Chroot
-	if chroot != nil {
-		_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_chroot_trampoline), uintptr(unsafe.Pointer(chroot)), 0, 0)
-		if err1 != 0 {
-			goto childerror
-		}
-	}
-
-	// User and groups
-	if cred := sys.Credential; cred != nil {
-		ngroups := uintptr(len(cred.Groups))
-		groups := uintptr(0)
-		if ngroups > 0 {
-			groups = uintptr(unsafe.Pointer(&cred.Groups[0]))
-		}
-		if !cred.NoSetGroups {
-			_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_setgroups_trampoline), ngroups, groups, 0)
-			if err1 != 0 {
-				goto childerror
-			}
-		}
-		_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_setgid_trampoline), uintptr(cred.Gid), 0, 0)
-		if err1 != 0 {
-			goto childerror
-		}
-		_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_setuid_trampoline), uintptr(cred.Uid), 0, 0)
-		if err1 != 0 {
-			goto childerror
-		}
-	}
-
-	// Chdir
-	if dir != nil {
-		_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_chdir_trampoline), uintptr(unsafe.Pointer(dir)), 0, 0)
-		if err1 != 0 {
-			goto childerror
-		}
-	}
-
-	// Pass 1: look for fd[i] < i and move those up above len(fd)
-	// so that pass 2 won't stomp on an fd it needs later.
-	if pipe < nextfd {
-		_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_dup2_trampoline), uintptr(pipe), uintptr(nextfd), 0)
-		if err1 != 0 {
-			goto childerror
-		}
-		rawSyscall(abi.FuncPCABI0(libc_fcntl_trampoline), uintptr(nextfd), F_SETFD, FD_CLOEXEC)
-		pipe = nextfd
-		nextfd++
-	}
-	for i = 0; i < len(fd); i++ {
-		if fd[i] >= 0 && fd[i] < int(i) {
-			if nextfd == pipe { // don't stomp on pipe
-				nextfd++
-			}
-			_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_dup2_trampoline), uintptr(fd[i]), uintptr(nextfd), 0)
-			if err1 != 0 {
-				goto childerror
-			}
-			rawSyscall(abi.FuncPCABI0(libc_fcntl_trampoline), uintptr(nextfd), F_SETFD, FD_CLOEXEC)
-			fd[i] = nextfd
-			nextfd++
-		}
-	}
-
-	// Pass 2: dup fd[i] down onto i.
-	for i = 0; i < len(fd); i++ {
-		if fd[i] == -1 {
-			rawSyscall(abi.FuncPCABI0(libc_close_trampoline), uintptr(i), 0, 0)
-			continue
-		}
-		if fd[i] == int(i) {
-			// dup2(i, i) won't clear close-on-exec flag on Linux,
-			// probably not elsewhere either.
-			_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_fcntl_trampoline), uintptr(fd[i]), F_SETFD, 0)
-			if err1 != 0 {
-				goto childerror
-			}
-			continue
-		}
-		// The new fd is created NOT close-on-exec,
-		// which is exactly what we want.
-		_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_dup2_trampoline), uintptr(fd[i]), uintptr(i), 0)
-		if err1 != 0 {
-			goto childerror
-		}
-	}
-
-	// By convention, we don't close-on-exec the fds we are
-	// started with, so if len(fd) < 3, close 0, 1, 2 as needed.
-	// Programs that know they inherit fds >= 3 will need
-	// to set them close-on-exec.
-	for i = len(fd); i < 3; i++ {
-		rawSyscall(abi.FuncPCABI0(libc_close_trampoline), uintptr(i), 0, 0)
-	}
-
-	// Detach fd 0 from tty
-	if sys.Noctty {
-		_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_ioctl_trampoline), 0, uintptr(TIOCNOTTY), 0)
-		if err1 != 0 {
-			goto childerror
-		}
-	}
-
-	// Set the controlling TTY to Ctty
-	if sys.Setctty {
-		_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_ioctl_trampoline), uintptr(sys.Ctty), uintptr(TIOCSCTTY), 0)
-		if err1 != 0 {
-			goto childerror
-		}
-	}
-
-	// Time to exec.
-	_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_execve_trampoline),
-		uintptr(unsafe.Pointer(argv0)),
-		uintptr(unsafe.Pointer(&argv[0])),
-		uintptr(unsafe.Pointer(&envv[0])))
-
-childerror:
-	// send error code on pipe
-	rawSyscall(abi.FuncPCABI0(libc_write_trampoline), uintptr(pipe), uintptr(unsafe.Pointer(&err1)), unsafe.Sizeof(err1))
-	for {
-		rawSyscall(abi.FuncPCABI0(libc_exit_trampoline), 253, 0, 0)
-	}
-}
diff --git a/contrib/go/_std_1.18/src/syscall/exec_linux.go b/contrib/go/_std_1.18/src/syscall/exec_linux.go
deleted file mode 100644
index 0f0dee8ea5..0000000000
--- a/contrib/go/_std_1.18/src/syscall/exec_linux.go
+++ /dev/null
@@ -1,621 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build linux
-
-package syscall
-
-import (
-	"internal/itoa"
-	"runtime"
-	"unsafe"
-)
-
-// SysProcIDMap holds Container ID to Host ID mappings used for User Namespaces in Linux.
-// See user_namespaces(7).
-type SysProcIDMap struct {
-	ContainerID int // Container ID.
-	HostID      int // Host ID.
-	Size        int // Size.
-}
-
-type SysProcAttr struct {
-	Chroot     string      // Chroot.
-	Credential *Credential // Credential.
-	// Ptrace tells the child to call ptrace(PTRACE_TRACEME).
-	// Call runtime.LockOSThread before starting a process with this set,
-	// and don't call UnlockOSThread until done with PtraceSyscall calls.
-	Ptrace bool
-	Setsid bool // Create session.
-	// Setpgid sets the process group ID of the child to Pgid,
-	// or, if Pgid == 0, to the new child's process ID.
-	Setpgid bool
-	// Setctty sets the controlling terminal of the child to
-	// file descriptor Ctty. Ctty must be a descriptor number
-	// in the child process: an index into ProcAttr.Files.
-	// This is only meaningful if Setsid is true.
-	Setctty bool
-	Noctty  bool // Detach fd 0 from controlling terminal
-	Ctty    int  // Controlling TTY fd
-	// Foreground places the child process group in the foreground.
-	// This implies Setpgid. The Ctty field must be set to
-	// the descriptor of the controlling TTY.
-	// Unlike Setctty, in this case Ctty must be a descriptor
-	// number in the parent process.
-	Foreground   bool
-	Pgid         int            // Child's process group ID if Setpgid.
-	Pdeathsig    Signal         // Signal that the process will get when its parent dies (Linux and FreeBSD only)
-	Cloneflags   uintptr        // Flags for clone calls (Linux only)
-	Unshareflags uintptr        // Flags for unshare calls (Linux only)
-	UidMappings  []SysProcIDMap // User ID mappings for user namespaces.
-	GidMappings  []SysProcIDMap // Group ID mappings for user namespaces.
-	// GidMappingsEnableSetgroups enabling setgroups syscall.
-	// If false, then setgroups syscall will be disabled for the child process.
-	// This parameter is no-op if GidMappings == nil. Otherwise for unprivileged
-	// users this should be set to false for mappings work.
-	GidMappingsEnableSetgroups bool
-	AmbientCaps                []uintptr // Ambient capabilities (Linux only)
-}
-
-var (
-	none  = [...]byte{'n', 'o', 'n', 'e', 0}
-	slash = [...]byte{'/', 0}
-)
-
-// Implemented in runtime package.
-func runtime_BeforeFork()
-func runtime_AfterFork()
-func runtime_AfterForkInChild()
-
-// Fork, dup fd onto 0..len(fd), and exec(argv0, argvv, envv) in child.
-// If a dup or exec fails, write the errno error to pipe.
-// (Pipe is close-on-exec so if exec succeeds, it will be closed.)
-// In the child, this function must not acquire any locks, because
-// they might have been locked at the time of the fork. This means
-// no rescheduling, no malloc calls, and no new stack segments.
-// For the same reason compiler does not race instrument it.
-// The calls to RawSyscall are okay because they are assembly
-// functions that do not grow the stack.
-//go:norace
-func forkAndExecInChild(argv0 *byte, argv, envv []*byte, chroot, dir *byte, attr *ProcAttr, sys *SysProcAttr, pipe int) (pid int, err Errno) {
-	// Set up and fork. This returns immediately in the parent or
-	// if there's an error.
-	r1, err1, p, locked := forkAndExecInChild1(argv0, argv, envv, chroot, dir, attr, sys, pipe)
-	if locked {
-		runtime_AfterFork()
-	}
-	if err1 != 0 {
-		return 0, err1
-	}
-
-	// parent; return PID
-	pid = int(r1)
-
-	if sys.UidMappings != nil || sys.GidMappings != nil {
-		Close(p[0])
-		var err2 Errno
-		// uid/gid mappings will be written after fork and unshare(2) for user
-		// namespaces.
-		if sys.Unshareflags&CLONE_NEWUSER == 0 {
-			if err := writeUidGidMappings(pid, sys); err != nil {
-				err2 = err.(Errno)
-			}
-		}
-		RawSyscall(SYS_WRITE, uintptr(p[1]), uintptr(unsafe.Pointer(&err2)), unsafe.Sizeof(err2))
-		Close(p[1])
-	}
-
-	return pid, 0
-}
-
-const _LINUX_CAPABILITY_VERSION_3 = 0x20080522
-
-type capHeader struct {
-	version uint32
-	pid     int32
-}
-
-type capData struct {
-	effective   uint32
-	permitted   uint32
-	inheritable uint32
-}
-type caps struct {
-	hdr  capHeader
-	data [2]capData
-}
-
-// See CAP_TO_INDEX in linux/capability.h:
-func capToIndex(cap uintptr) uintptr { return cap >> 5 }
-
-// See CAP_TO_MASK in linux/capability.h:
-func capToMask(cap uintptr) uint32 { return 1 << uint(cap&31) }
-
-// forkAndExecInChild1 implements the body of forkAndExecInChild up to
-// the parent's post-fork path. This is a separate function so we can
-// separate the child's and parent's stack frames if we're using
-// vfork.
-//
-// This is go:noinline because the point is to keep the stack frames
-// of this and forkAndExecInChild separate.
-//
-//go:noinline
-//go:norace
-func forkAndExecInChild1(argv0 *byte, argv, envv []*byte, chroot, dir *byte, attr *ProcAttr, sys *SysProcAttr, pipe int) (r1 uintptr, err1 Errno, p [2]int, locked bool) {
-	// Defined in linux/prctl.h starting with Linux 4.3.
-	const (
-		PR_CAP_AMBIENT       = 0x2f
-		PR_CAP_AMBIENT_RAISE = 0x2
-	)
-
-	// vfork requires that the child not touch any of the parent's
-	// active stack frames. Hence, the child does all post-fork
-	// processing in this stack frame and never returns, while the
-	// parent returns immediately from this frame and does all
-	// post-fork processing in the outer frame.
-	// Declare all variables at top in case any
-	// declarations require heap allocation (e.g., err1).
-	var (
-		err2                      Errno
-		nextfd                    int
-		i                         int
-		caps                      caps
-		fd1                       uintptr
-		puid, psetgroups, pgid    []byte
-		uidmap, setgroups, gidmap []byte
-	)
-
-	if sys.UidMappings != nil {
-		puid = []byte("/proc/self/uid_map\000")
-		uidmap = formatIDMappings(sys.UidMappings)
-	}
-
-	if sys.GidMappings != nil {
-		psetgroups = []byte("/proc/self/setgroups\000")
-		pgid = []byte("/proc/self/gid_map\000")
-
-		if sys.GidMappingsEnableSetgroups {
-			setgroups = []byte("allow\000")
-		} else {
-			setgroups = []byte("deny\000")
-		}
-		gidmap = formatIDMappings(sys.GidMappings)
-	}
-
-	// Record parent PID so child can test if it has died.
-	ppid, _ := rawSyscallNoError(SYS_GETPID, 0, 0, 0)
-
-	// Guard against side effects of shuffling fds below.
-	// Make sure that nextfd is beyond any currently open files so
-	// that we can't run the risk of overwriting any of them.
-	fd := make([]int, len(attr.Files))
-	nextfd = len(attr.Files)
-	for i, ufd := range attr.Files {
-		if nextfd < int(ufd) {
-			nextfd = int(ufd)
-		}
-		fd[i] = int(ufd)
-	}
-	nextfd++
-
-	// Allocate another pipe for parent to child communication for
-	// synchronizing writing of User ID/Group ID mappings.
-	if sys.UidMappings != nil || sys.GidMappings != nil {
-		if err := forkExecPipe(p[:]); err != nil {
-			err1 = err.(Errno)
-			return
-		}
-	}
-
-	// About to call fork.
-	// No more allocation or calls of non-assembly functions.
-	runtime_BeforeFork()
-	locked = true
-	switch {
-	case sys.Cloneflags&CLONE_NEWUSER == 0 && sys.Unshareflags&CLONE_NEWUSER == 0:
-		r1, err1 = rawVforkSyscall(SYS_CLONE, uintptr(SIGCHLD|CLONE_VFORK|CLONE_VM)|sys.Cloneflags)
-	case runtime.GOARCH == "s390x":
-		r1, _, err1 = RawSyscall6(SYS_CLONE, 0, uintptr(SIGCHLD)|sys.Cloneflags, 0, 0, 0, 0)
-	default:
-		r1, _, err1 = RawSyscall6(SYS_CLONE, uintptr(SIGCHLD)|sys.Cloneflags, 0, 0, 0, 0, 0)
-	}
-	if err1 != 0 || r1 != 0 {
-		// If we're in the parent, we must return immediately
-		// so we're not in the same stack frame as the child.
-		// This can at most use the return PC, which the child
-		// will not modify, and the results of
-		// rawVforkSyscall, which must have been written after
-		// the child was replaced.
-		return
-	}
-
-	// Fork succeeded, now in child.
-
-	// Enable the "keep capabilities" flag to set ambient capabilities later.
-	if len(sys.AmbientCaps) > 0 {
-		_, _, err1 = RawSyscall6(SYS_PRCTL, PR_SET_KEEPCAPS, 1, 0, 0, 0, 0)
-		if err1 != 0 {
-			goto childerror
-		}
-	}
-
-	// Wait for User ID/Group ID mappings to be written.
-	if sys.UidMappings != nil || sys.GidMappings != nil {
-		if _, _, err1 = RawSyscall(SYS_CLOSE, uintptr(p[1]), 0, 0); err1 != 0 {
-			goto childerror
-		}
-		r1, _, err1 = RawSyscall(SYS_READ, uintptr(p[0]), uintptr(unsafe.Pointer(&err2)), unsafe.Sizeof(err2))
-		if err1 != 0 {
-			goto childerror
-		}
-		if r1 != unsafe.Sizeof(err2) {
-			err1 = EINVAL
-			goto childerror
-		}
-		if err2 != 0 {
-			err1 = err2
-			goto childerror
-		}
-	}
-
-	// Session ID
-	if sys.Setsid {
-		_, _, err1 = RawSyscall(SYS_SETSID, 0, 0, 0)
-		if err1 != 0 {
-			goto childerror
-		}
-	}
-
-	// Set process group
-	if sys.Setpgid || sys.Foreground {
-		// Place child in process group.
-		_, _, err1 = RawSyscall(SYS_SETPGID, 0, uintptr(sys.Pgid), 0)
-		if err1 != 0 {
-			goto childerror
-		}
-	}
-
-	if sys.Foreground {
-		pgrp := int32(sys.Pgid)
-		if pgrp == 0 {
-			r1, _ = rawSyscallNoError(SYS_GETPID, 0, 0, 0)
-
-			pgrp = int32(r1)
-		}
-
-		// Place process group in foreground.
-		_, _, err1 = RawSyscall(SYS_IOCTL, uintptr(sys.Ctty), uintptr(TIOCSPGRP), uintptr(unsafe.Pointer(&pgrp)))
-		if err1 != 0 {
-			goto childerror
-		}
-	}
-
-	// Restore the signal mask. We do this after TIOCSPGRP to avoid
-	// having the kernel send a SIGTTOU signal to the process group.
-	runtime_AfterForkInChild()
-
-	// Unshare
-	if sys.Unshareflags != 0 {
-		_, _, err1 = RawSyscall(SYS_UNSHARE, sys.Unshareflags, 0, 0)
-		if err1 != 0 {
-			goto childerror
-		}
-
-		if sys.Unshareflags&CLONE_NEWUSER != 0 && sys.GidMappings != nil {
-			dirfd := int(_AT_FDCWD)
-			if fd1, _, err1 = RawSyscall6(SYS_OPENAT, uintptr(dirfd), uintptr(unsafe.Pointer(&psetgroups[0])), uintptr(O_WRONLY), 0, 0, 0); err1 != 0 {
-				goto childerror
-			}
-			r1, _, err1 = RawSyscall(SYS_WRITE, uintptr(fd1), uintptr(unsafe.Pointer(&setgroups[0])), uintptr(len(setgroups)))
-			if err1 != 0 {
-				goto childerror
-			}
-			if _, _, err1 = RawSyscall(SYS_CLOSE, uintptr(fd1), 0, 0); err1 != 0 {
-				goto childerror
-			}
-
-			if fd1, _, err1 = RawSyscall6(SYS_OPENAT, uintptr(dirfd), uintptr(unsafe.Pointer(&pgid[0])), uintptr(O_WRONLY), 0, 0, 0); err1 != 0 {
-				goto childerror
-			}
-			r1, _, err1 = RawSyscall(SYS_WRITE, uintptr(fd1), uintptr(unsafe.Pointer(&gidmap[0])), uintptr(len(gidmap)))
-			if err1 != 0 {
-				goto childerror
-			}
-			if _, _, err1 = RawSyscall(SYS_CLOSE, uintptr(fd1), 0, 0); err1 != 0 {
-				goto childerror
-			}
-		}
-
-		if sys.Unshareflags&CLONE_NEWUSER != 0 && sys.UidMappings != nil {
-			dirfd := int(_AT_FDCWD)
-			if fd1, _, err1 = RawSyscall6(SYS_OPENAT, uintptr(dirfd), uintptr(unsafe.Pointer(&puid[0])), uintptr(O_WRONLY), 0, 0, 0); err1 != 0 {
-				goto childerror
-			}
-			r1, _, err1 = RawSyscall(SYS_WRITE, uintptr(fd1), uintptr(unsafe.Pointer(&uidmap[0])), uintptr(len(uidmap)))
-			if err1 != 0 {
-				goto childerror
-			}
-			if _, _, err1 = RawSyscall(SYS_CLOSE, uintptr(fd1), 0, 0); err1 != 0 {
-				goto childerror
-			}
-		}
-
-		// The unshare system call in Linux doesn't unshare mount points
-		// mounted with --shared. Systemd mounts / with --shared. For a
-		// long discussion of the pros and cons of this see debian bug 739593.
-		// The Go model of unsharing is more like Plan 9, where you ask
-		// to unshare and the namespaces are unconditionally unshared.
-		// To make this model work we must further mark / as MS_PRIVATE.
-		// This is what the standard unshare command does.
-		if sys.Unshareflags&CLONE_NEWNS == CLONE_NEWNS {
-			_, _, err1 = RawSyscall6(SYS_MOUNT, uintptr(unsafe.Pointer(&none[0])), uintptr(unsafe.Pointer(&slash[0])), 0, MS_REC|MS_PRIVATE, 0, 0)
-			if err1 != 0 {
-				goto childerror
-			}
-		}
-	}
-
-	// Chroot
-	if chroot != nil {
-		_, _, err1 = RawSyscall(SYS_CHROOT, uintptr(unsafe.Pointer(chroot)), 0, 0)
-		if err1 != 0 {
-			goto childerror
-		}
-	}
-
-	// User and groups
-	if cred := sys.Credential; cred != nil {
-		ngroups := uintptr(len(cred.Groups))
-		groups := uintptr(0)
-		if ngroups > 0 {
-			groups = uintptr(unsafe.Pointer(&cred.Groups[0]))
-		}
-		if !(sys.GidMappings != nil && !sys.GidMappingsEnableSetgroups && ngroups == 0) && !cred.NoSetGroups {
-			_, _, err1 = RawSyscall(_SYS_setgroups, ngroups, groups, 0)
-			if err1 != 0 {
-				goto childerror
-			}
-		}
-		_, _, err1 = RawSyscall(sys_SETGID, uintptr(cred.Gid), 0, 0)
-		if err1 != 0 {
-			goto childerror
-		}
-		_, _, err1 = RawSyscall(sys_SETUID, uintptr(cred.Uid), 0, 0)
-		if err1 != 0 {
-			goto childerror
-		}
-	}
-
-	if len(sys.AmbientCaps) != 0 {
-		// Ambient capabilities were added in the 4.3 kernel,
-		// so it is safe to always use _LINUX_CAPABILITY_VERSION_3.
-		caps.hdr.version = _LINUX_CAPABILITY_VERSION_3
-
-		if _, _, err1 := RawSyscall(SYS_CAPGET, uintptr(unsafe.Pointer(&caps.hdr)), uintptr(unsafe.Pointer(&caps.data[0])), 0); err1 != 0 {
-			goto childerror
-		}
-
-		for _, c := range sys.AmbientCaps {
-			// Add the c capability to the permitted and inheritable capability mask,
-			// otherwise we will not be able to add it to the ambient capability mask.
-			caps.data[capToIndex(c)].permitted |= capToMask(c)
-			caps.data[capToIndex(c)].inheritable |= capToMask(c)
-		}
-
-		if _, _, err1 := RawSyscall(SYS_CAPSET, uintptr(unsafe.Pointer(&caps.hdr)), uintptr(unsafe.Pointer(&caps.data[0])), 0); err1 != 0 {
-			goto childerror
-		}
-
-		for _, c := range sys.AmbientCaps {
-			_, _, err1 = RawSyscall6(SYS_PRCTL, PR_CAP_AMBIENT, uintptr(PR_CAP_AMBIENT_RAISE), c, 0, 0, 0)
-			if err1 != 0 {
-				goto childerror
-			}
-		}
-	}
-
-	// Chdir
-	if dir != nil {
-		_, _, err1 = RawSyscall(SYS_CHDIR, uintptr(unsafe.Pointer(dir)), 0, 0)
-		if err1 != 0 {
-			goto childerror
-		}
-	}
-
-	// Parent death signal
-	if sys.Pdeathsig != 0 {
-		_, _, err1 = RawSyscall6(SYS_PRCTL, PR_SET_PDEATHSIG, uintptr(sys.Pdeathsig), 0, 0, 0, 0)
-		if err1 != 0 {
-			goto childerror
-		}
-
-		// Signal self if parent is already dead. This might cause a
-		// duplicate signal in rare cases, but it won't matter when
-		// using SIGKILL.
-		r1, _ = rawSyscallNoError(SYS_GETPPID, 0, 0, 0)
-		if r1 != ppid {
-			pid, _ := rawSyscallNoError(SYS_GETPID, 0, 0, 0)
-			_, _, err1 := RawSyscall(SYS_KILL, pid, uintptr(sys.Pdeathsig), 0)
-			if err1 != 0 {
-				goto childerror
-			}
-		}
-	}
-
-	// Pass 1: look for fd[i] < i and move those up above len(fd)
-	// so that pass 2 won't stomp on an fd it needs later.
-	if pipe < nextfd {
-		_, _, err1 = RawSyscall(SYS_DUP3, uintptr(pipe), uintptr(nextfd), O_CLOEXEC)
-		if err1 != 0 {
-			goto childerror
-		}
-		pipe = nextfd
-		nextfd++
-	}
-	for i = 0; i < len(fd); i++ {
-		if fd[i] >= 0 && fd[i] < int(i) {
-			if nextfd == pipe { // don't stomp on pipe
-				nextfd++
-			}
-			_, _, err1 = RawSyscall(SYS_DUP3, uintptr(fd[i]), uintptr(nextfd), O_CLOEXEC)
-			if err1 != 0 {
-				goto childerror
-			}
-			fd[i] = nextfd
-			nextfd++
-		}
-	}
-
-	// Pass 2: dup fd[i] down onto i.
-	for i = 0; i < len(fd); i++ {
-		if fd[i] == -1 {
-			RawSyscall(SYS_CLOSE, uintptr(i), 0, 0)
-			continue
-		}
-		if fd[i] == int(i) {
-			// dup2(i, i) won't clear close-on-exec flag on Linux,
-			// probably not elsewhere either.
-			_, _, err1 = RawSyscall(fcntl64Syscall, uintptr(fd[i]), F_SETFD, 0)
-			if err1 != 0 {
-				goto childerror
-			}
-			continue
-		}
-		// The new fd is created NOT close-on-exec,
-		// which is exactly what we want.
-		_, _, err1 = RawSyscall(SYS_DUP3, uintptr(fd[i]), uintptr(i), 0)
-		if err1 != 0 {
-			goto childerror
-		}
-	}
-
-	// By convention, we don't close-on-exec the fds we are
-	// started with, so if len(fd) < 3, close 0, 1, 2 as needed.
-	// Programs that know they inherit fds >= 3 will need
-	// to set them close-on-exec.
-	for i = len(fd); i < 3; i++ {
-		RawSyscall(SYS_CLOSE, uintptr(i), 0, 0)
-	}
-
-	// Detach fd 0 from tty
-	if sys.Noctty {
-		_, _, err1 = RawSyscall(SYS_IOCTL, 0, uintptr(TIOCNOTTY), 0)
-		if err1 != 0 {
-			goto childerror
-		}
-	}
-
-	// Set the controlling TTY to Ctty
-	if sys.Setctty {
-		_, _, err1 = RawSyscall(SYS_IOCTL, uintptr(sys.Ctty), uintptr(TIOCSCTTY), 1)
-		if err1 != 0 {
-			goto childerror
-		}
-	}
-
-	// Enable tracing if requested.
-	// Do this right before exec so that we don't unnecessarily trace the runtime
-	// setting up after the fork. See issue #21428.
-	if sys.Ptrace {
-		_, _, err1 = RawSyscall(SYS_PTRACE, uintptr(PTRACE_TRACEME), 0, 0)
-		if err1 != 0 {
-			goto childerror
-		}
-	}
-
-	// Time to exec.
-	_, _, err1 = RawSyscall(SYS_EXECVE,
-		uintptr(unsafe.Pointer(argv0)),
-		uintptr(unsafe.Pointer(&argv[0])),
-		uintptr(unsafe.Pointer(&envv[0])))
-
-childerror:
-	// send error code on pipe
-	RawSyscall(SYS_WRITE, uintptr(pipe), uintptr(unsafe.Pointer(&err1)), unsafe.Sizeof(err1))
-	for {
-		RawSyscall(SYS_EXIT, 253, 0, 0)
-	}
-}
-
-// Try to open a pipe with O_CLOEXEC set on both file descriptors.
-func forkExecPipe(p []int) (err error) {
-	return Pipe2(p, O_CLOEXEC)
-}
-
-func formatIDMappings(idMap []SysProcIDMap) []byte {
-	var data []byte
-	for _, im := range idMap {
-		data = append(data, []byte(itoa.Itoa(im.ContainerID)+" "+itoa.Itoa(im.HostID)+" "+itoa.Itoa(im.Size)+"\n")...)
-	}
-	return data
-}
-
-// writeIDMappings writes the user namespace User ID or Group ID mappings to the specified path.
-func writeIDMappings(path string, idMap []SysProcIDMap) error {
-	fd, err := Open(path, O_RDWR, 0)
-	if err != nil {
-		return err
-	}
-
-	if _, err := Write(fd, formatIDMappings(idMap)); err != nil {
-		Close(fd)
-		return err
-	}
-
-	if err := Close(fd); err != nil {
-		return err
-	}
-
-	return nil
-}
-
-// writeSetgroups writes to /proc/PID/setgroups "deny" if enable is false
-// and "allow" if enable is true.
-// This is needed since kernel 3.19, because you can't write gid_map without
-// disabling setgroups() system call.
-func writeSetgroups(pid int, enable bool) error {
-	sgf := "/proc/" + itoa.Itoa(pid) + "/setgroups"
-	fd, err := Open(sgf, O_RDWR, 0)
-	if err != nil {
-		return err
-	}
-
-	var data []byte
-	if enable {
-		data = []byte("allow")
-	} else {
-		data = []byte("deny")
-	}
-
-	if _, err := Write(fd, data); err != nil {
-		Close(fd)
-		return err
-	}
-
-	return Close(fd)
-}
-
-// writeUidGidMappings writes User ID and Group ID mappings for user namespaces
-// for a process and it is called from the parent process.
-func writeUidGidMappings(pid int, sys *SysProcAttr) error {
-	if sys.UidMappings != nil {
-		uidf := "/proc/" + itoa.Itoa(pid) + "/uid_map"
-		if err := writeIDMappings(uidf, sys.UidMappings); err != nil {
-			return err
-		}
-	}
-
-	if sys.GidMappings != nil {
-		// If the kernel is too old to support /proc/PID/setgroups, writeSetGroups will return ENOENT; this is OK.
-		if err := writeSetgroups(pid, sys.GidMappingsEnableSetgroups); err != nil && err != ENOENT {
-			return err
-		}
-		gidf := "/proc/" + itoa.Itoa(pid) + "/gid_map"
-		if err := writeIDMappings(gidf, sys.GidMappings); err != nil {
-			return err
-		}
-	}
-
-	return nil
-}
diff --git a/contrib/go/_std_1.18/src/syscall/exec_unix.go b/contrib/go/_std_1.18/src/syscall/exec_unix.go
deleted file mode 100644
index 0e41959ffe..0000000000
--- a/contrib/go/_std_1.18/src/syscall/exec_unix.go
+++ /dev/null
@@ -1,306 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
-
-// Fork, exec, wait, etc.
-
-package syscall
-
-import (
-	errorspkg "errors"
-	"internal/bytealg"
-	"runtime"
-	"sync"
-	"unsafe"
-)
-
-// Lock synchronizing creation of new file descriptors with fork.
-//
-// We want the child in a fork/exec sequence to inherit only the
-// file descriptors we intend. To do that, we mark all file
-// descriptors close-on-exec and then, in the child, explicitly
-// unmark the ones we want the exec'ed program to keep.
-// Unix doesn't make this easy: there is, in general, no way to
-// allocate a new file descriptor close-on-exec. Instead you
-// have to allocate the descriptor and then mark it close-on-exec.
-// If a fork happens between those two events, the child's exec
-// will inherit an unwanted file descriptor.
-//
-// This lock solves that race: the create new fd/mark close-on-exec
-// operation is done holding ForkLock for reading, and the fork itself
-// is done holding ForkLock for writing. At least, that's the idea.
-// There are some complications.
-//
-// Some system calls that create new file descriptors can block
-// for arbitrarily long times: open on a hung NFS server or named
-// pipe, accept on a socket, and so on. We can't reasonably grab
-// the lock across those operations.
-//
-// It is worse to inherit some file descriptors than others.
-// If a non-malicious child accidentally inherits an open ordinary file,
-// that's not a big deal. On the other hand, if a long-lived child
-// accidentally inherits the write end of a pipe, then the reader
-// of that pipe will not see EOF until that child exits, potentially
-// causing the parent program to hang. This is a common problem
-// in threaded C programs that use popen.
-//
-// Luckily, the file descriptors that are most important not to
-// inherit are not the ones that can take an arbitrarily long time
-// to create: pipe returns instantly, and the net package uses
-// non-blocking I/O to accept on a listening socket.
-// The rules for which file descriptor-creating operations use the
-// ForkLock are as follows:
-//
-// 1) Pipe. Does not block. Use the ForkLock.
-// 2) Socket. Does not block. Use the ForkLock.
-// 3) Accept. If using non-blocking mode, use the ForkLock.
-//             Otherwise, live with the race.
-// 4) Open. Can block. Use O_CLOEXEC if available (Linux).
-//             Otherwise, live with the race.
-// 5) Dup. Does not block. Use the ForkLock.
-//             On Linux, could use fcntl F_DUPFD_CLOEXEC
-//             instead of the ForkLock, but only for dup(fd, -1).
-
-var ForkLock sync.RWMutex
-
-// StringSlicePtr converts a slice of strings to a slice of pointers
-// to NUL-terminated byte arrays. If any string contains a NUL byte
-// this function panics instead of returning an error.
-//
-// Deprecated: Use SlicePtrFromStrings instead.
-func StringSlicePtr(ss []string) []*byte {
-	bb := make([]*byte, len(ss)+1)
-	for i := 0; i < len(ss); i++ {
-		bb[i] = StringBytePtr(ss[i])
-	}
-	bb[len(ss)] = nil
-	return bb
-}
-
-// SlicePtrFromStrings converts a slice of strings to a slice of
-// pointers to NUL-terminated byte arrays. If any string contains
-// a NUL byte, it returns (nil, EINVAL).
-func SlicePtrFromStrings(ss []string) ([]*byte, error) {
-	n := 0
-	for _, s := range ss {
-		if bytealg.IndexByteString(s, 0) != -1 {
-			return nil, EINVAL
-		}
-		n += len(s) + 1 // +1 for NUL
-	}
-	bb := make([]*byte, len(ss)+1)
-	b := make([]byte, n)
-	n = 0
-	for i, s := range ss {
-		bb[i] = &b[n]
-		copy(b[n:], s)
-		n += len(s) + 1
-	}
-	return bb, nil
-}
-
-func CloseOnExec(fd int) { fcntl(fd, F_SETFD, FD_CLOEXEC) }
-
-func SetNonblock(fd int, nonblocking bool) (err error) {
-	flag, err := fcntl(fd, F_GETFL, 0)
-	if err != nil {
-		return err
-	}
-	if nonblocking {
-		flag |= O_NONBLOCK
-	} else {
-		flag &^= O_NONBLOCK
-	}
-	_, err = fcntl(fd, F_SETFL, flag)
-	return err
-}
-
-// Credential holds user and group identities to be assumed
-// by a child process started by StartProcess.
-type Credential struct {
-	Uid         uint32   // User ID.
-	Gid         uint32   // Group ID.
-	Groups      []uint32 // Supplementary group IDs.
-	NoSetGroups bool     // If true, don't set supplementary groups
-}
-
-// ProcAttr holds attributes that will be applied to a new process started
-// by StartProcess.
-type ProcAttr struct {
-	Dir   string    // Current working directory.
-	Env   []string  // Environment.
-	Files []uintptr // File descriptors.
-	Sys   *SysProcAttr
-}
-
-var zeroProcAttr ProcAttr
-var zeroSysProcAttr SysProcAttr
-
-func forkExec(argv0 string, argv []string, attr *ProcAttr) (pid int, err error) {
-	var p [2]int
-	var n int
-	var err1 Errno
-	var wstatus WaitStatus
-
-	if attr == nil {
-		attr = &zeroProcAttr
-	}
-	sys := attr.Sys
-	if sys == nil {
-		sys = &zeroSysProcAttr
-	}
-
-	// Convert args to C form.
-	argv0p, err := BytePtrFromString(argv0)
-	if err != nil {
-		return 0, err
-	}
-	argvp, err := SlicePtrFromStrings(argv)
-	if err != nil {
-		return 0, err
-	}
-	envvp, err := SlicePtrFromStrings(attr.Env)
-	if err != nil {
-		return 0, err
-	}
-
-	if (runtime.GOOS == "freebsd" || runtime.GOOS == "dragonfly") && len(argv[0]) > len(argv0) {
-		argvp[0] = argv0p
-	}
-
-	var chroot *byte
-	if sys.Chroot != "" {
-		chroot, err = BytePtrFromString(sys.Chroot)
-		if err != nil {
-			return 0, err
-		}
-	}
-	var dir *byte
-	if attr.Dir != "" {
-		dir, err = BytePtrFromString(attr.Dir)
-		if err != nil {
-			return 0, err
-		}
-	}
-
-	// Both Setctty and Foreground use the Ctty field,
-	// but they give it slightly different meanings.
-	if sys.Setctty && sys.Foreground {
-		return 0, errorspkg.New("both Setctty and Foreground set in SysProcAttr")
-	}
-	if sys.Setctty && sys.Ctty >= len(attr.Files) {
-		return 0, errorspkg.New("Setctty set but Ctty not valid in child")
-	}
-
-	// Acquire the fork lock so that no other threads
-	// create new fds that are not yet close-on-exec
-	// before we fork.
-	ForkLock.Lock()
-
-	// Allocate child status pipe close on exec.
-	if err = forkExecPipe(p[:]); err != nil {
-		ForkLock.Unlock()
-		return 0, err
-	}
-
-	// Kick off child.
-	pid, err1 = forkAndExecInChild(argv0p, argvp, envvp, chroot, dir, attr, sys, p[1])
-	if err1 != 0 {
-		Close(p[0])
-		Close(p[1])
-		ForkLock.Unlock()
-		return 0, Errno(err1)
-	}
-	ForkLock.Unlock()
-
-	// Read child error status from pipe.
-	Close(p[1])
-	for {
-		n, err = readlen(p[0], (*byte)(unsafe.Pointer(&err1)), int(unsafe.Sizeof(err1)))
-		if err != EINTR {
-			break
-		}
-	}
-	Close(p[0])
-	if err != nil || n != 0 {
-		if n == int(unsafe.Sizeof(err1)) {
-			err = Errno(err1)
-		}
-		if err == nil {
-			err = EPIPE
-		}
-
-		// Child failed; wait for it to exit, to make sure
-		// the zombies don't accumulate.
-		_, err1 := Wait4(pid, &wstatus, 0, nil)
-		for err1 == EINTR {
-			_, err1 = Wait4(pid, &wstatus, 0, nil)
-		}
-		return 0, err
-	}
-
-	// Read got EOF, so pipe closed on exec, so exec succeeded.
-	return pid, nil
-}
-
-// Combination of fork and exec, careful to be thread safe.
-func ForkExec(argv0 string, argv []string, attr *ProcAttr) (pid int, err error) {
-	return forkExec(argv0, argv, attr)
-}
-
-// StartProcess wraps ForkExec for package os.
-func StartProcess(argv0 string, argv []string, attr *ProcAttr) (pid int, handle uintptr, err error) {
-	pid, err = forkExec(argv0, argv, attr)
-	return pid, 0, err
-}
-
-// Implemented in runtime package.
-func runtime_BeforeExec()
-func runtime_AfterExec()
-
-// execveLibc is non-nil on OS using libc syscall, set to execve in exec_libc.go; this
-// avoids a build dependency for other platforms.
-var execveLibc func(path uintptr, argv uintptr, envp uintptr) Errno
-var execveDarwin func(path *byte, argv **byte, envp **byte) error
-var execveOpenBSD func(path *byte, argv **byte, envp **byte) error
-
-// Exec invokes the execve(2) system call.
-func Exec(argv0 string, argv []string, envv []string) (err error) {
-	argv0p, err := BytePtrFromString(argv0)
-	if err != nil {
-		return err
-	}
-	argvp, err := SlicePtrFromStrings(argv)
-	if err != nil {
-		return err
-	}
-	envvp, err := SlicePtrFromStrings(envv)
-	if err != nil {
-		return err
-	}
-	runtime_BeforeExec()
-
-	var err1 error
-	if runtime.GOOS == "solaris" || runtime.GOOS == "illumos" || runtime.GOOS == "aix" {
-		// RawSyscall should never be used on Solaris, illumos, or AIX.
-		err1 = execveLibc(
-			uintptr(unsafe.Pointer(argv0p)),
-			uintptr(unsafe.Pointer(&argvp[0])),
-			uintptr(unsafe.Pointer(&envvp[0])))
-	} else if runtime.GOOS == "darwin" || runtime.GOOS == "ios" {
-		// Similarly on Darwin.
-		err1 = execveDarwin(argv0p, &argvp[0], &envvp[0])
-	} else if runtime.GOOS == "openbsd" && (runtime.GOARCH == "386" || runtime.GOARCH == "amd64" || runtime.GOARCH == "arm" || runtime.GOARCH == "arm64") {
-		// Similarly on OpenBSD.
-		err1 = execveOpenBSD(argv0p, &argvp[0], &envvp[0])
-	} else {
-		_, _, err1 = RawSyscall(SYS_EXECVE,
-			uintptr(unsafe.Pointer(argv0p)),
-			uintptr(unsafe.Pointer(&argvp[0])),
-			uintptr(unsafe.Pointer(&envvp[0])))
-	}
-	runtime_AfterExec()
-	return err1
-}
diff --git a/contrib/go/_std_1.18/src/syscall/forkpipe.go b/contrib/go/_std_1.18/src/syscall/forkpipe.go
deleted file mode 100644
index 6f7d29ce67..0000000000
--- a/contrib/go/_std_1.18/src/syscall/forkpipe.go
+++ /dev/null
@@ -1,21 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || solaris
-
-package syscall
-
-// Try to open a pipe with O_CLOEXEC set on both file descriptors.
-func forkExecPipe(p []int) error {
-	err := Pipe(p)
-	if err != nil {
-		return err
-	}
-	_, err = fcntl(p[0], F_SETFD, FD_CLOEXEC)
-	if err != nil {
-		return err
-	}
-	_, err = fcntl(p[1], F_SETFD, FD_CLOEXEC)
-	return err
-}
diff --git a/contrib/go/_std_1.18/src/syscall/sockcmsg_unix.go b/contrib/go/_std_1.18/src/syscall/sockcmsg_unix.go
deleted file mode 100644
index a3dcf818da..0000000000
--- a/contrib/go/_std_1.18/src/syscall/sockcmsg_unix.go
+++ /dev/null
@@ -1,92 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
-
-// Socket control messages
-
-package syscall
-
-import (
-	"unsafe"
-)
-
-// CmsgLen returns the value to store in the Len field of the Cmsghdr
-// structure, taking into account any necessary alignment.
-func CmsgLen(datalen int) int {
-	return cmsgAlignOf(SizeofCmsghdr) + datalen
-}
-
-// CmsgSpace returns the number of bytes an ancillary element with
-// payload of the passed data length occupies.
-func CmsgSpace(datalen int) int {
-	return cmsgAlignOf(SizeofCmsghdr) + cmsgAlignOf(datalen)
-}
-
-func (h *Cmsghdr) data(offset uintptr) unsafe.Pointer {
-	return unsafe.Pointer(uintptr(unsafe.Pointer(h)) + uintptr(cmsgAlignOf(SizeofCmsghdr)) + offset)
-}
-
-// SocketControlMessage represents a socket control message.
-type SocketControlMessage struct {
-	Header Cmsghdr
-	Data   []byte
-}
-
-// ParseSocketControlMessage parses b as an array of socket control
-// messages.
-func ParseSocketControlMessage(b []byte) ([]SocketControlMessage, error) {
-	var msgs []SocketControlMessage
-	i := 0
-	for i+CmsgLen(0) <= len(b) {
-		h, dbuf, err := socketControlMessageHeaderAndData(b[i:])
-		if err != nil {
-			return nil, err
-		}
-		m := SocketControlMessage{Header: *h, Data: dbuf}
-		msgs = append(msgs, m)
-		i += cmsgAlignOf(int(h.Len))
-	}
-	return msgs, nil
-}
-
-func socketControlMessageHeaderAndData(b []byte) (*Cmsghdr, []byte, error) {
-	h := (*Cmsghdr)(unsafe.Pointer(&b[0]))
-	if h.Len < SizeofCmsghdr || uint64(h.Len) > uint64(len(b)) {
-		return nil, nil, EINVAL
-	}
-	return h, b[cmsgAlignOf(SizeofCmsghdr):h.Len], nil
-}
-
-// UnixRights encodes a set of open file descriptors into a socket
-// control message for sending to another process.
-func UnixRights(fds ...int) []byte {
-	datalen := len(fds) * 4
-	b := make([]byte, CmsgSpace(datalen))
-	h := (*Cmsghdr)(unsafe.Pointer(&b[0]))
-	h.Level = SOL_SOCKET
-	h.Type = SCM_RIGHTS
-	h.SetLen(CmsgLen(datalen))
-	for i, fd := range fds {
-		*(*int32)(h.data(4 * uintptr(i))) = int32(fd)
-	}
-	return b
-}
-
-// ParseUnixRights decodes a socket control message that contains an
-// integer array of open file descriptors from another process.
-func ParseUnixRights(m *SocketControlMessage) ([]int, error) {
-	if m.Header.Level != SOL_SOCKET {
-		return nil, EINVAL
-	}
-	if m.Header.Type != SCM_RIGHTS {
-		return nil, EINVAL
-	}
-	fds := make([]int, len(m.Data)>>2)
-	for i, j := 0, 0; i < len(m.Data); i += 4 {
-		fds[j] = int(*(*int32)(unsafe.Pointer(&m.Data[i])))
-		j++
-	}
-	return fds, nil
-}
diff --git a/contrib/go/_std_1.18/src/syscall/syscall.go b/contrib/go/_std_1.18/src/syscall/syscall.go
deleted file mode 100644
index 91173033ee..0000000000
--- a/contrib/go/_std_1.18/src/syscall/syscall.go
+++ /dev/null
@@ -1,103 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package syscall contains an interface to the low-level operating system
-// primitives. The details vary depending on the underlying system, and
-// by default, godoc will display the syscall documentation for the current
-// system. If you want godoc to display syscall documentation for another
-// system, set $GOOS and $GOARCH to the desired system. For example, if
-// you want to view documentation for freebsd/arm on linux/amd64, set $GOOS
-// to freebsd and $GOARCH to arm.
-// The primary use of syscall is inside other packages that provide a more
-// portable interface to the system, such as "os", "time" and "net".  Use
-// those packages rather than this one if you can.
-// For details of the functions and data types in this package consult
-// the manuals for the appropriate operating system.
-// These calls return err == nil to indicate success; otherwise
-// err is an operating system error describing the failure.
-// On most systems, that error has type syscall.Errno.
-//
-// Deprecated: this package is locked down. Callers should use the
-// corresponding package in the golang.org/x/sys repository instead.
-// That is also where updates required by new systems or versions
-// should be applied. See https://golang.org/s/go1.4-syscall for more
-// information.
-//
-package syscall
-
-//go:generate go run ./mksyscall_windows.go -systemdll -output zsyscall_windows.go syscall_windows.go security_windows.go
-
-// StringByteSlice converts a string to a NUL-terminated []byte,
-// If s contains a NUL byte this function panics instead of
-// returning an error.
-//
-// Deprecated: Use ByteSliceFromString instead.
-func StringByteSlice(s string) []byte {
-	a, err := ByteSliceFromString(s)
-	if err != nil {
-		panic("syscall: string with NUL passed to StringByteSlice")
-	}
-	return a
-}
-
-// ByteSliceFromString returns a NUL-terminated slice of bytes
-// containing the text of s. If s contains a NUL byte at any
-// location, it returns (nil, EINVAL).
-func ByteSliceFromString(s string) ([]byte, error) {
-	for i := 0; i < len(s); i++ {
-		if s[i] == 0 {
-			return nil, EINVAL
-		}
-	}
-	a := make([]byte, len(s)+1)
-	copy(a, s)
-	return a, nil
-}
-
-// StringBytePtr returns a pointer to a NUL-terminated array of bytes.
-// If s contains a NUL byte this function panics instead of returning
-// an error.
-//
-// Deprecated: Use BytePtrFromString instead.
-func StringBytePtr(s string) *byte { return &StringByteSlice(s)[0] }
-
-// BytePtrFromString returns a pointer to a NUL-terminated array of
-// bytes containing the text of s. If s contains a NUL byte at any
-// location, it returns (nil, EINVAL).
-func BytePtrFromString(s string) (*byte, error) {
-	a, err := ByteSliceFromString(s)
-	if err != nil {
-		return nil, err
-	}
-	return &a[0], nil
-}
-
-// Single-word zero for use when we need a valid pointer to 0 bytes.
-// See mksyscall.pl.
-var _zero uintptr
-
-// Unix returns the time stored in ts as seconds plus nanoseconds.
-func (ts *Timespec) Unix() (sec int64, nsec int64) {
-	return int64(ts.Sec), int64(ts.Nsec)
-}
-
-// Unix returns the time stored in tv as seconds plus nanoseconds.
-func (tv *Timeval) Unix() (sec int64, nsec int64) {
-	return int64(tv.Sec), int64(tv.Usec) * 1000
-}
-
-// Nano returns the time stored in ts as nanoseconds.
-func (ts *Timespec) Nano() int64 {
-	return int64(ts.Sec)*1e9 + int64(ts.Nsec)
-}
-
-// Nano returns the time stored in tv as nanoseconds.
-func (tv *Timeval) Nano() int64 {
-	return int64(tv.Sec)*1e9 + int64(tv.Usec)*1000
-}
-
-// Getpagesize and Exit are provided by the runtime.
-
-func Getpagesize() int
-func Exit(code int)
diff --git a/contrib/go/_std_1.18/src/syscall/syscall_darwin.go b/contrib/go/_std_1.18/src/syscall/syscall_darwin.go
deleted file mode 100644
index 902d6e77e1..0000000000
--- a/contrib/go/_std_1.18/src/syscall/syscall_darwin.go
+++ /dev/null
@@ -1,332 +0,0 @@
-// Copyright 2009,2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Darwin system calls.
-// This file is compiled as ordinary Go code,
-// but it is also input to mksyscall,
-// which parses the //sys lines and generates system call stubs.
-// Note that sometimes we use a lowercase //sys name and wrap
-// it in our own nicer implementation, either here or in
-// syscall_bsd.go or syscall_unix.go.
-
-package syscall
-
-import (
-	"internal/abi"
-	"unsafe"
-)
-
-type SockaddrDatalink struct {
-	Len    uint8
-	Family uint8
-	Index  uint16
-	Type   uint8
-	Nlen   uint8
-	Alen   uint8
-	Slen   uint8
-	Data   [12]int8
-	raw    RawSockaddrDatalink
-}
-
-// Translate "kern.hostname" to []_C_int{0,1,2,3}.
-func nametomib(name string) (mib []_C_int, err error) {
-	const siz = unsafe.Sizeof(mib[0])
-
-	// NOTE(rsc): It seems strange to set the buffer to have
-	// size CTL_MAXNAME+2 but use only CTL_MAXNAME
-	// as the size. I don't know why the +2 is here, but the
-	// kernel uses +2 for its own implementation of this function.
-	// I am scared that if we don't include the +2 here, the kernel
-	// will silently write 2 words farther than we specify
-	// and we'll get memory corruption.
-	var buf [CTL_MAXNAME + 2]_C_int
-	n := uintptr(CTL_MAXNAME) * siz
-
-	p := (*byte)(unsafe.Pointer(&buf[0]))
-	bytes, err := ByteSliceFromString(name)
-	if err != nil {
-		return nil, err
-	}
-
-	// Magic sysctl: "setting" 0.3 to a string name
-	// lets you read back the array of integers form.
-	if err = sysctl([]_C_int{0, 3}, p, &n, &bytes[0], uintptr(len(name))); err != nil {
-		return nil, err
-	}
-	return buf[0 : n/siz], nil
-}
-
-func direntIno(buf []byte) (uint64, bool) {
-	return readInt(buf, unsafe.Offsetof(Dirent{}.Ino), unsafe.Sizeof(Dirent{}.Ino))
-}
-
-func direntReclen(buf []byte) (uint64, bool) {
-	return readInt(buf, unsafe.Offsetof(Dirent{}.Reclen), unsafe.Sizeof(Dirent{}.Reclen))
-}
-
-func direntNamlen(buf []byte) (uint64, bool) {
-	return readInt(buf, unsafe.Offsetof(Dirent{}.Namlen), unsafe.Sizeof(Dirent{}.Namlen))
-}
-
-func PtraceAttach(pid int) (err error) { return ptrace(PT_ATTACH, pid, 0, 0) }
-func PtraceDetach(pid int) (err error) { return ptrace(PT_DETACH, pid, 0, 0) }
-
-//sysnb pipe(p *[2]int32) (err error)
-
-func Pipe(p []int) (err error) {
-	if len(p) != 2 {
-		return EINVAL
-	}
-	var q [2]int32
-	err = pipe(&q)
-	if err == nil {
-		p[0] = int(q[0])
-		p[1] = int(q[1])
-	}
-	return
-}
-
-func Getfsstat(buf []Statfs_t, flags int) (n int, err error) {
-	var _p0 unsafe.Pointer
-	var bufsize uintptr
-	if len(buf) > 0 {
-		_p0 = unsafe.Pointer(&buf[0])
-		bufsize = unsafe.Sizeof(Statfs_t{}) * uintptr(len(buf))
-	}
-	r0, _, e1 := syscall(abi.FuncPCABI0(libc_getfsstat_trampoline), uintptr(_p0), bufsize, uintptr(flags))
-	n = int(r0)
-	if e1 != 0 {
-		err = e1
-	}
-	return
-}
-
-func libc_getfsstat_trampoline()
-
-//go:cgo_import_dynamic libc_getfsstat getfsstat "/usr/lib/libSystem.B.dylib"
-
-//sys	utimensat(dirfd int, path string, times *[2]Timespec, flags int) (err error)
-
-/*
- * Wrapped
- */
-
-//sys	kill(pid int, signum int, posix int) (err error)
-
-func Kill(pid int, signum Signal) (err error) { return kill(pid, int(signum), 1) }
-
-/*
- * Exposed directly
- */
-//sys	Access(path string, mode uint32) (err error)
-//sys	Adjtime(delta *Timeval, olddelta *Timeval) (err error)
-//sys	Chdir(path string) (err error)
-//sys	Chflags(path string, flags int) (err error)
-//sys	Chmod(path string, mode uint32) (err error)
-//sys	Chown(path string, uid int, gid int) (err error)
-//sys	Chroot(path string) (err error)
-//sys	Close(fd int) (err error)
-//sys	closedir(dir uintptr) (err error)
-//sys	Dup(fd int) (nfd int, err error)
-//sys	Dup2(from int, to int) (err error)
-//sys	Exchangedata(path1 string, path2 string, options int) (err error)
-//sys	Fchdir(fd int) (err error)
-//sys	Fchflags(fd int, flags int) (err error)
-//sys	Fchmod(fd int, mode uint32) (err error)
-//sys	Fchown(fd int, uid int, gid int) (err error)
-//sys	Flock(fd int, how int) (err error)
-//sys	Fpathconf(fd int, name int) (val int, err error)
-//sys	Fsync(fd int) (err error)
-//  Fsync is not called for os.File.Sync(). Please see internal/poll/fd_fsync_darwin.go
-//sys	Ftruncate(fd int, length int64) (err error)
-//sys	Getdtablesize() (size int)
-//sysnb	Getegid() (egid int)
-//sysnb	Geteuid() (uid int)
-//sysnb	Getgid() (gid int)
-//sysnb	Getpgid(pid int) (pgid int, err error)
-//sysnb	Getpgrp() (pgrp int)
-//sysnb	Getpid() (pid int)
-//sysnb	Getppid() (ppid int)
-//sys	Getpriority(which int, who int) (prio int, err error)
-//sysnb	Getrlimit(which int, lim *Rlimit) (err error)
-//sysnb	Getrusage(who int, rusage *Rusage) (err error)
-//sysnb	Getsid(pid int) (sid int, err error)
-//sysnb	Getuid() (uid int)
-//sysnb	Issetugid() (tainted bool)
-//sys	Kqueue() (fd int, err error)
-//sys	Lchown(path string, uid int, gid int) (err error)
-//sys	Link(path string, link string) (err error)
-//sys	Listen(s int, backlog int) (err error)
-//sys	Mkdir(path string, mode uint32) (err error)
-//sys	Mkfifo(path string, mode uint32) (err error)
-//sys	Mknod(path string, mode uint32, dev int) (err error)
-//sys	Mlock(b []byte) (err error)
-//sys	Mlockall(flags int) (err error)
-//sys	Mprotect(b []byte, prot int) (err error)
-//sys	Munlock(b []byte) (err error)
-//sys	Munlockall() (err error)
-//sys	Open(path string, mode int, perm uint32) (fd int, err error)
-//sys	Pathconf(path string, name int) (val int, err error)
-//sys	Pread(fd int, p []byte, offset int64) (n int, err error)
-//sys	Pwrite(fd int, p []byte, offset int64) (n int, err error)
-//sys	read(fd int, p []byte) (n int, err error)
-//sys	readdir_r(dir uintptr, entry *Dirent, result **Dirent) (res Errno)
-//sys	Readlink(path string, buf []byte) (n int, err error)
-//sys	Rename(from string, to string) (err error)
-//sys	Revoke(path string) (err error)
-//sys	Rmdir(path string) (err error)
-//sys	Seek(fd int, offset int64, whence int) (newoffset int64, err error) = SYS_lseek
-//sys	Select(n int, r *FdSet, w *FdSet, e *FdSet, timeout *Timeval) (err error)
-//sys	Setegid(egid int) (err error)
-//sysnb	Seteuid(euid int) (err error)
-//sysnb	Setgid(gid int) (err error)
-//sys	Setlogin(name string) (err error)
-//sysnb	Setpgid(pid int, pgid int) (err error)
-//sys	Setpriority(which int, who int, prio int) (err error)
-//sys	Setprivexec(flag int) (err error)
-//sysnb	Setregid(rgid int, egid int) (err error)
-//sysnb	Setreuid(ruid int, euid int) (err error)
-//sysnb	Setrlimit(which int, lim *Rlimit) (err error)
-//sysnb	Setsid() (pid int, err error)
-//sysnb	Settimeofday(tp *Timeval) (err error)
-//sysnb	Setuid(uid int) (err error)
-//sys	Symlink(path string, link string) (err error)
-//sys	Sync() (err error)
-//sys	Truncate(path string, length int64) (err error)
-//sys	Umask(newmask int) (oldmask int)
-//sys	Undelete(path string) (err error)
-//sys	Unlink(path string) (err error)
-//sys	Unmount(path string, flags int) (err error)
-//sys	write(fd int, p []byte) (n int, err error)
-//sys	writev(fd int, iovecs []Iovec) (cnt uintptr, err error)
-//sys   mmap(addr uintptr, length uintptr, prot int, flag int, fd int, pos int64) (ret uintptr, err error)
-//sys   munmap(addr uintptr, length uintptr) (err error)
-//sysnb fork() (pid int, err error)
-//sysnb ioctl(fd int, req int, arg int) (err error)
-//sysnb ioctlPtr(fd int, req uint, arg unsafe.Pointer) (err error) = SYS_ioctl
-//sysnb execve(path *byte, argv **byte, envp **byte) (err error)
-//sysnb exit(res int) (err error)
-//sys	sysctl(mib []_C_int, old *byte, oldlen *uintptr, new *byte, newlen uintptr) (err error)
-//sys	fcntlPtr(fd int, cmd int, arg unsafe.Pointer) (val int, err error) = SYS_fcntl
-//sys   unlinkat(fd int, path string, flags int) (err error)
-//sys   openat(fd int, path string, flags int, perm uint32) (fdret int, err error)
-//sys	getcwd(buf []byte) (n int, err error)
-
-func init() {
-	execveDarwin = execve
-}
-
-func fdopendir(fd int) (dir uintptr, err error) {
-	r0, _, e1 := syscallPtr(abi.FuncPCABI0(libc_fdopendir_trampoline), uintptr(fd), 0, 0)
-	dir = uintptr(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_fdopendir_trampoline()
-
-//go:cgo_import_dynamic libc_fdopendir fdopendir "/usr/lib/libSystem.B.dylib"
-
-func readlen(fd int, buf *byte, nbuf int) (n int, err error) {
-	r0, _, e1 := syscall(abi.FuncPCABI0(libc_read_trampoline), uintptr(fd), uintptr(unsafe.Pointer(buf)), uintptr(nbuf))
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func writelen(fd int, buf *byte, nbuf int) (n int, err error) {
-	r0, _, e1 := syscall(abi.FuncPCABI0(libc_write_trampoline), uintptr(fd), uintptr(unsafe.Pointer(buf)), uintptr(nbuf))
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func Getdirentries(fd int, buf []byte, basep *uintptr) (n int, err error) {
-	// Simulate Getdirentries using fdopendir/readdir_r/closedir.
-	// We store the number of entries to skip in the seek
-	// offset of fd. See issue #31368.
-	// It's not the full required semantics, but should handle the case
-	// of calling Getdirentries or ReadDirent repeatedly.
-	// It won't handle assigning the results of lseek to *basep, or handle
-	// the directory being edited underfoot.
-	skip, err := Seek(fd, 0, 1 /* SEEK_CUR */)
-	if err != nil {
-		return 0, err
-	}
-
-	// We need to duplicate the incoming file descriptor
-	// because the caller expects to retain control of it, but
-	// fdopendir expects to take control of its argument.
-	// Just Dup'ing the file descriptor is not enough, as the
-	// result shares underlying state. Use openat to make a really
-	// new file descriptor referring to the same directory.
-	fd2, err := openat(fd, ".", O_RDONLY, 0)
-	if err != nil {
-		return 0, err
-	}
-	d, err := fdopendir(fd2)
-	if err != nil {
-		Close(fd2)
-		return 0, err
-	}
-	defer closedir(d)
-
-	var cnt int64
-	for {
-		var entry Dirent
-		var entryp *Dirent
-		e := readdir_r(d, &entry, &entryp)
-		if e != 0 {
-			return n, errnoErr(e)
-		}
-		if entryp == nil {
-			break
-		}
-		if skip > 0 {
-			skip--
-			cnt++
-			continue
-		}
-		reclen := int(entry.Reclen)
-		if reclen > len(buf) {
-			// Not enough room. Return for now.
-			// The counter will let us know where we should start up again.
-			// Note: this strategy for suspending in the middle and
-			// restarting is O(n^2) in the length of the directory. Oh well.
-			break
-		}
-		// Copy entry into return buffer.
-		s := struct {
-			ptr unsafe.Pointer
-			siz int
-			cap int
-		}{ptr: unsafe.Pointer(&entry), siz: reclen, cap: reclen}
-		copy(buf, *(*[]byte)(unsafe.Pointer(&s)))
-		buf = buf[reclen:]
-		n += reclen
-		cnt++
-	}
-	// Set the seek offset of the input fd to record
-	// how many files we've already returned.
-	_, err = Seek(fd, cnt, 0 /* SEEK_SET */)
-	if err != nil {
-		return n, err
-	}
-
-	return n, nil
-}
-
-// Implemented in the runtime package (runtime/sys_darwin.go)
-func syscall(fn, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno)
-func syscall6(fn, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno)
-func syscall6X(fn, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno)
-func rawSyscall(fn, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno)
-func rawSyscall6(fn, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno)
-func syscallPtr(fn, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno)
diff --git a/contrib/go/_std_1.18/src/syscall/syscall_linux.go b/contrib/go/_std_1.18/src/syscall/syscall_linux.go
deleted file mode 100644
index f32020ca6c..0000000000
--- a/contrib/go/_std_1.18/src/syscall/syscall_linux.go
+++ /dev/null
@@ -1,1150 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Linux system calls.
-// This file is compiled as ordinary Go code,
-// but it is also input to mksyscall,
-// which parses the //sys lines and generates system call stubs.
-// Note that sometimes we use a lowercase //sys name and
-// wrap it in our own nicer implementation.
-
-package syscall
-
-import (
-	"internal/itoa"
-	"unsafe"
-)
-
-func rawSyscallNoError(trap, a1, a2, a3 uintptr) (r1, r2 uintptr)
-
-/*
- * Wrapped
- */
-
-func Access(path string, mode uint32) (err error) {
-	return Faccessat(_AT_FDCWD, path, mode, 0)
-}
-
-func Chmod(path string, mode uint32) (err error) {
-	return Fchmodat(_AT_FDCWD, path, mode, 0)
-}
-
-func Chown(path string, uid int, gid int) (err error) {
-	return Fchownat(_AT_FDCWD, path, uid, gid, 0)
-}
-
-func Creat(path string, mode uint32) (fd int, err error) {
-	return Open(path, O_CREAT|O_WRONLY|O_TRUNC, mode)
-}
-
-func isGroupMember(gid int) bool {
-	groups, err := Getgroups()
-	if err != nil {
-		return false
-	}
-
-	for _, g := range groups {
-		if g == gid {
-			return true
-		}
-	}
-	return false
-}
-
-//sys	faccessat(dirfd int, path string, mode uint32) (err error)
-
-func Faccessat(dirfd int, path string, mode uint32, flags int) (err error) {
-	if flags & ^(_AT_SYMLINK_NOFOLLOW|_AT_EACCESS) != 0 {
-		return EINVAL
-	}
-
-	// The Linux kernel faccessat system call does not take any flags.
-	// The glibc faccessat implements the flags itself; see
-	// https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/unix/sysv/linux/faccessat.c;hb=HEAD
-	// Because people naturally expect syscall.Faccessat to act
-	// like C faccessat, we do the same.
-
-	if flags == 0 {
-		return faccessat(dirfd, path, mode)
-	}
-
-	var st Stat_t
-	if err := fstatat(dirfd, path, &st, flags&_AT_SYMLINK_NOFOLLOW); err != nil {
-		return err
-	}
-
-	mode &= 7
-	if mode == 0 {
-		return nil
-	}
-
-	var uid int
-	if flags&_AT_EACCESS != 0 {
-		uid = Geteuid()
-	} else {
-		uid = Getuid()
-	}
-
-	if uid == 0 {
-		if mode&1 == 0 {
-			// Root can read and write any file.
-			return nil
-		}
-		if st.Mode&0111 != 0 {
-			// Root can execute any file that anybody can execute.
-			return nil
-		}
-		return EACCES
-	}
-
-	var fmode uint32
-	if uint32(uid) == st.Uid {
-		fmode = (st.Mode >> 6) & 7
-	} else {
-		var gid int
-		if flags&_AT_EACCESS != 0 {
-			gid = Getegid()
-		} else {
-			gid = Getgid()
-		}
-
-		if uint32(gid) == st.Gid || isGroupMember(int(st.Gid)) {
-			fmode = (st.Mode >> 3) & 7
-		} else {
-			fmode = st.Mode & 7
-		}
-	}
-
-	if fmode&mode == mode {
-		return nil
-	}
-
-	return EACCES
-}
-
-//sys	fchmodat(dirfd int, path string, mode uint32) (err error)
-
-func Fchmodat(dirfd int, path string, mode uint32, flags int) (err error) {
-	// Linux fchmodat doesn't support the flags parameter. Mimick glibc's behavior
-	// and check the flags. Otherwise the mode would be applied to the symlink
-	// destination which is not what the user expects.
-	if flags&^_AT_SYMLINK_NOFOLLOW != 0 {
-		return EINVAL
-	} else if flags&_AT_SYMLINK_NOFOLLOW != 0 {
-		return EOPNOTSUPP
-	}
-	return fchmodat(dirfd, path, mode)
-}
-
-//sys	linkat(olddirfd int, oldpath string, newdirfd int, newpath string, flags int) (err error)
-
-func Link(oldpath string, newpath string) (err error) {
-	return linkat(_AT_FDCWD, oldpath, _AT_FDCWD, newpath, 0)
-}
-
-func Mkdir(path string, mode uint32) (err error) {
-	return Mkdirat(_AT_FDCWD, path, mode)
-}
-
-func Mknod(path string, mode uint32, dev int) (err error) {
-	return Mknodat(_AT_FDCWD, path, mode, dev)
-}
-
-func Open(path string, mode int, perm uint32) (fd int, err error) {
-	return openat(_AT_FDCWD, path, mode|O_LARGEFILE, perm)
-}
-
-//sys	openat(dirfd int, path string, flags int, mode uint32) (fd int, err error)
-
-func Openat(dirfd int, path string, flags int, mode uint32) (fd int, err error) {
-	return openat(dirfd, path, flags|O_LARGEFILE, mode)
-}
-
-func Pipe(p []int) error {
-	return Pipe2(p, 0)
-}
-
-//sysnb pipe2(p *[2]_C_int, flags int) (err error)
-
-func Pipe2(p []int, flags int) error {
-	if len(p) != 2 {
-		return EINVAL
-	}
-	var pp [2]_C_int
-	err := pipe2(&pp, flags)
-	if err == nil {
-		p[0] = int(pp[0])
-		p[1] = int(pp[1])
-	}
-	return err
-}
-
-//sys	readlinkat(dirfd int, path string, buf []byte) (n int, err error)
-
-func Readlink(path string, buf []byte) (n int, err error) {
-	return readlinkat(_AT_FDCWD, path, buf)
-}
-
-func Rename(oldpath string, newpath string) (err error) {
-	return Renameat(_AT_FDCWD, oldpath, _AT_FDCWD, newpath)
-}
-
-func Rmdir(path string) error {
-	return unlinkat(_AT_FDCWD, path, _AT_REMOVEDIR)
-}
-
-//sys	symlinkat(oldpath string, newdirfd int, newpath string) (err error)
-
-func Symlink(oldpath string, newpath string) (err error) {
-	return symlinkat(oldpath, _AT_FDCWD, newpath)
-}
-
-func Unlink(path string) error {
-	return unlinkat(_AT_FDCWD, path, 0)
-}
-
-//sys	unlinkat(dirfd int, path string, flags int) (err error)
-
-func Unlinkat(dirfd int, path string) error {
-	return unlinkat(dirfd, path, 0)
-}
-
-func Utimes(path string, tv []Timeval) (err error) {
-	if len(tv) != 2 {
-		return EINVAL
-	}
-	return utimes(path, (*[2]Timeval)(unsafe.Pointer(&tv[0])))
-}
-
-//sys	utimensat(dirfd int, path string, times *[2]Timespec, flag int) (err error)
-
-func UtimesNano(path string, ts []Timespec) (err error) {
-	if len(ts) != 2 {
-		return EINVAL
-	}
-	return utimensat(_AT_FDCWD, path, (*[2]Timespec)(unsafe.Pointer(&ts[0])), 0)
-}
-
-func Futimesat(dirfd int, path string, tv []Timeval) (err error) {
-	if len(tv) != 2 {
-		return EINVAL
-	}
-	return futimesat(dirfd, path, (*[2]Timeval)(unsafe.Pointer(&tv[0])))
-}
-
-func Futimes(fd int, tv []Timeval) (err error) {
-	// Believe it or not, this is the best we can do on Linux
-	// (and is what glibc does).
-	return Utimes("/proc/self/fd/"+itoa.Itoa(fd), tv)
-}
-
-const ImplementsGetwd = true
-
-//sys	Getcwd(buf []byte) (n int, err error)
-
-func Getwd() (wd string, err error) {
-	var buf [PathMax]byte
-	n, err := Getcwd(buf[0:])
-	if err != nil {
-		return "", err
-	}
-	// Getcwd returns the number of bytes written to buf, including the NUL.
-	if n < 1 || n > len(buf) || buf[n-1] != 0 {
-		return "", EINVAL
-	}
-	return string(buf[0 : n-1]), nil
-}
-
-func Getgroups() (gids []int, err error) {
-	n, err := getgroups(0, nil)
-	if err != nil {
-		return nil, err
-	}
-	if n == 0 {
-		return nil, nil
-	}
-
-	// Sanity check group count. Max is 1<<16 on Linux.
-	if n < 0 || n > 1<<20 {
-		return nil, EINVAL
-	}
-
-	a := make([]_Gid_t, n)
-	n, err = getgroups(n, &a[0])
-	if err != nil {
-		return nil, err
-	}
-	gids = make([]int, n)
-	for i, v := range a[0:n] {
-		gids[i] = int(v)
-	}
-	return
-}
-
-var cgo_libc_setgroups unsafe.Pointer // non-nil if cgo linked.
-
-func Setgroups(gids []int) (err error) {
-	n := uintptr(len(gids))
-	if n == 0 {
-		if cgo_libc_setgroups == nil {
-			if _, _, e1 := AllThreadsSyscall(_SYS_setgroups, 0, 0, 0); e1 != 0 {
-				err = errnoErr(e1)
-			}
-			return
-		}
-		if ret := cgocaller(cgo_libc_setgroups, 0, 0); ret != 0 {
-			err = errnoErr(Errno(ret))
-		}
-		return
-	}
-
-	a := make([]_Gid_t, len(gids))
-	for i, v := range gids {
-		a[i] = _Gid_t(v)
-	}
-	if cgo_libc_setgroups == nil {
-		if _, _, e1 := AllThreadsSyscall(_SYS_setgroups, n, uintptr(unsafe.Pointer(&a[0])), 0); e1 != 0 {
-			err = errnoErr(e1)
-		}
-		return
-	}
-	if ret := cgocaller(cgo_libc_setgroups, n, uintptr(unsafe.Pointer(&a[0]))); ret != 0 {
-		err = errnoErr(Errno(ret))
-	}
-	return
-}
-
-type WaitStatus uint32
-
-// Wait status is 7 bits at bottom, either 0 (exited),
-// 0x7F (stopped), or a signal number that caused an exit.
-// The 0x80 bit is whether there was a core dump.
-// An extra number (exit code, signal causing a stop)
-// is in the high bits. At least that's the idea.
-// There are various irregularities. For example, the
-// "continued" status is 0xFFFF, distinguishing itself
-// from stopped via the core dump bit.
-
-const (
-	mask    = 0x7F
-	core    = 0x80
-	exited  = 0x00
-	stopped = 0x7F
-	shift   = 8
-)
-
-func (w WaitStatus) Exited() bool { return w&mask == exited }
-
-func (w WaitStatus) Signaled() bool { return w&mask != stopped && w&mask != exited }
-
-func (w WaitStatus) Stopped() bool { return w&0xFF == stopped }
-
-func (w WaitStatus) Continued() bool { return w == 0xFFFF }
-
-func (w WaitStatus) CoreDump() bool { return w.Signaled() && w&core != 0 }
-
-func (w WaitStatus) ExitStatus() int {
-	if !w.Exited() {
-		return -1
-	}
-	return int(w>>shift) & 0xFF
-}
-
-func (w WaitStatus) Signal() Signal {
-	if !w.Signaled() {
-		return -1
-	}
-	return Signal(w & mask)
-}
-
-func (w WaitStatus) StopSignal() Signal {
-	if !w.Stopped() {
-		return -1
-	}
-	return Signal(w>>shift) & 0xFF
-}
-
-func (w WaitStatus) TrapCause() int {
-	if w.StopSignal() != SIGTRAP {
-		return -1
-	}
-	return int(w>>shift) >> 8
-}
-
-//sys	wait4(pid int, wstatus *_C_int, options int, rusage *Rusage) (wpid int, err error)
-
-func Wait4(pid int, wstatus *WaitStatus, options int, rusage *Rusage) (wpid int, err error) {
-	var status _C_int
-	wpid, err = wait4(pid, &status, options, rusage)
-	if wstatus != nil {
-		*wstatus = WaitStatus(status)
-	}
-	return
-}
-
-func Mkfifo(path string, mode uint32) (err error) {
-	return Mknod(path, mode|S_IFIFO, 0)
-}
-
-func (sa *SockaddrInet4) sockaddr() (unsafe.Pointer, _Socklen, error) {
-	if sa.Port < 0 || sa.Port > 0xFFFF {
-		return nil, 0, EINVAL
-	}
-	sa.raw.Family = AF_INET
-	p := (*[2]byte)(unsafe.Pointer(&sa.raw.Port))
-	p[0] = byte(sa.Port >> 8)
-	p[1] = byte(sa.Port)
-	sa.raw.Addr = sa.Addr
-	return unsafe.Pointer(&sa.raw), SizeofSockaddrInet4, nil
-}
-
-func (sa *SockaddrInet6) sockaddr() (unsafe.Pointer, _Socklen, error) {
-	if sa.Port < 0 || sa.Port > 0xFFFF {
-		return nil, 0, EINVAL
-	}
-	sa.raw.Family = AF_INET6
-	p := (*[2]byte)(unsafe.Pointer(&sa.raw.Port))
-	p[0] = byte(sa.Port >> 8)
-	p[1] = byte(sa.Port)
-	sa.raw.Scope_id = sa.ZoneId
-	sa.raw.Addr = sa.Addr
-	return unsafe.Pointer(&sa.raw), SizeofSockaddrInet6, nil
-}
-
-func (sa *SockaddrUnix) sockaddr() (unsafe.Pointer, _Socklen, error) {
-	name := sa.Name
-	n := len(name)
-	if n > len(sa.raw.Path) {
-		return nil, 0, EINVAL
-	}
-	if n == len(sa.raw.Path) && name[0] != '@' {
-		return nil, 0, EINVAL
-	}
-	sa.raw.Family = AF_UNIX
-	for i := 0; i < n; i++ {
-		sa.raw.Path[i] = int8(name[i])
-	}
-	// length is family (uint16), name, NUL.
-	sl := _Socklen(2)
-	if n > 0 {
-		sl += _Socklen(n) + 1
-	}
-	if sa.raw.Path[0] == '@' {
-		sa.raw.Path[0] = 0
-		// Don't count trailing NUL for abstract address.
-		sl--
-	}
-
-	return unsafe.Pointer(&sa.raw), sl, nil
-}
-
-type SockaddrLinklayer struct {
-	Protocol uint16
-	Ifindex  int
-	Hatype   uint16
-	Pkttype  uint8
-	Halen    uint8
-	Addr     [8]byte
-	raw      RawSockaddrLinklayer
-}
-
-func (sa *SockaddrLinklayer) sockaddr() (unsafe.Pointer, _Socklen, error) {
-	if sa.Ifindex < 0 || sa.Ifindex > 0x7fffffff {
-		return nil, 0, EINVAL
-	}
-	sa.raw.Family = AF_PACKET
-	sa.raw.Protocol = sa.Protocol
-	sa.raw.Ifindex = int32(sa.Ifindex)
-	sa.raw.Hatype = sa.Hatype
-	sa.raw.Pkttype = sa.Pkttype
-	sa.raw.Halen = sa.Halen
-	sa.raw.Addr = sa.Addr
-	return unsafe.Pointer(&sa.raw), SizeofSockaddrLinklayer, nil
-}
-
-type SockaddrNetlink struct {
-	Family uint16
-	Pad    uint16
-	Pid    uint32
-	Groups uint32
-	raw    RawSockaddrNetlink
-}
-
-func (sa *SockaddrNetlink) sockaddr() (unsafe.Pointer, _Socklen, error) {
-	sa.raw.Family = AF_NETLINK
-	sa.raw.Pad = sa.Pad
-	sa.raw.Pid = sa.Pid
-	sa.raw.Groups = sa.Groups
-	return unsafe.Pointer(&sa.raw), SizeofSockaddrNetlink, nil
-}
-
-func anyToSockaddr(rsa *RawSockaddrAny) (Sockaddr, error) {
-	switch rsa.Addr.Family {
-	case AF_NETLINK:
-		pp := (*RawSockaddrNetlink)(unsafe.Pointer(rsa))
-		sa := new(SockaddrNetlink)
-		sa.Family = pp.Family
-		sa.Pad = pp.Pad
-		sa.Pid = pp.Pid
-		sa.Groups = pp.Groups
-		return sa, nil
-
-	case AF_PACKET:
-		pp := (*RawSockaddrLinklayer)(unsafe.Pointer(rsa))
-		sa := new(SockaddrLinklayer)
-		sa.Protocol = pp.Protocol
-		sa.Ifindex = int(pp.Ifindex)
-		sa.Hatype = pp.Hatype
-		sa.Pkttype = pp.Pkttype
-		sa.Halen = pp.Halen
-		sa.Addr = pp.Addr
-		return sa, nil
-
-	case AF_UNIX:
-		pp := (*RawSockaddrUnix)(unsafe.Pointer(rsa))
-		sa := new(SockaddrUnix)
-		if pp.Path[0] == 0 {
-			// "Abstract" Unix domain socket.
-			// Rewrite leading NUL as @ for textual display.
-			// (This is the standard convention.)
-			// Not friendly to overwrite in place,
-			// but the callers below don't care.
-			pp.Path[0] = '@'
-		}
-
-		// Assume path ends at NUL.
-		// This is not technically the Linux semantics for
-		// abstract Unix domain sockets--they are supposed
-		// to be uninterpreted fixed-size binary blobs--but
-		// everyone uses this convention.
-		n := 0
-		for n < len(pp.Path) && pp.Path[n] != 0 {
-			n++
-		}
-		bytes := (*[len(pp.Path)]byte)(unsafe.Pointer(&pp.Path[0]))[0:n]
-		sa.Name = string(bytes)
-		return sa, nil
-
-	case AF_INET:
-		pp := (*RawSockaddrInet4)(unsafe.Pointer(rsa))
-		sa := new(SockaddrInet4)
-		p := (*[2]byte)(unsafe.Pointer(&pp.Port))
-		sa.Port = int(p[0])<<8 + int(p[1])
-		sa.Addr = pp.Addr
-		return sa, nil
-
-	case AF_INET6:
-		pp := (*RawSockaddrInet6)(unsafe.Pointer(rsa))
-		sa := new(SockaddrInet6)
-		p := (*[2]byte)(unsafe.Pointer(&pp.Port))
-		sa.Port = int(p[0])<<8 + int(p[1])
-		sa.ZoneId = pp.Scope_id
-		sa.Addr = pp.Addr
-		return sa, nil
-	}
-	return nil, EAFNOSUPPORT
-}
-
-func Accept(fd int) (nfd int, sa Sockaddr, err error) {
-	var rsa RawSockaddrAny
-	var len _Socklen = SizeofSockaddrAny
-	nfd, err = accept4(fd, &rsa, &len, 0)
-	if err != nil {
-		return
-	}
-	sa, err = anyToSockaddr(&rsa)
-	if err != nil {
-		Close(nfd)
-		nfd = 0
-	}
-	return
-}
-
-func Accept4(fd int, flags int) (nfd int, sa Sockaddr, err error) {
-	var rsa RawSockaddrAny
-	var len _Socklen = SizeofSockaddrAny
-	nfd, err = accept4(fd, &rsa, &len, flags)
-	if err != nil {
-		return
-	}
-	if len > SizeofSockaddrAny {
-		panic("RawSockaddrAny too small")
-	}
-	sa, err = anyToSockaddr(&rsa)
-	if err != nil {
-		Close(nfd)
-		nfd = 0
-	}
-	return
-}
-
-func Getsockname(fd int) (sa Sockaddr, err error) {
-	var rsa RawSockaddrAny
-	var len _Socklen = SizeofSockaddrAny
-	if err = getsockname(fd, &rsa, &len); err != nil {
-		return
-	}
-	return anyToSockaddr(&rsa)
-}
-
-func GetsockoptInet4Addr(fd, level, opt int) (value [4]byte, err error) {
-	vallen := _Socklen(4)
-	err = getsockopt(fd, level, opt, unsafe.Pointer(&value[0]), &vallen)
-	return value, err
-}
-
-func GetsockoptIPMreq(fd, level, opt int) (*IPMreq, error) {
-	var value IPMreq
-	vallen := _Socklen(SizeofIPMreq)
-	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
-	return &value, err
-}
-
-func GetsockoptIPMreqn(fd, level, opt int) (*IPMreqn, error) {
-	var value IPMreqn
-	vallen := _Socklen(SizeofIPMreqn)
-	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
-	return &value, err
-}
-
-func GetsockoptIPv6Mreq(fd, level, opt int) (*IPv6Mreq, error) {
-	var value IPv6Mreq
-	vallen := _Socklen(SizeofIPv6Mreq)
-	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
-	return &value, err
-}
-
-func GetsockoptIPv6MTUInfo(fd, level, opt int) (*IPv6MTUInfo, error) {
-	var value IPv6MTUInfo
-	vallen := _Socklen(SizeofIPv6MTUInfo)
-	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
-	return &value, err
-}
-
-func GetsockoptICMPv6Filter(fd, level, opt int) (*ICMPv6Filter, error) {
-	var value ICMPv6Filter
-	vallen := _Socklen(SizeofICMPv6Filter)
-	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
-	return &value, err
-}
-
-func GetsockoptUcred(fd, level, opt int) (*Ucred, error) {
-	var value Ucred
-	vallen := _Socklen(SizeofUcred)
-	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
-	return &value, err
-}
-
-func SetsockoptIPMreqn(fd, level, opt int, mreq *IPMreqn) (err error) {
-	return setsockopt(fd, level, opt, unsafe.Pointer(mreq), unsafe.Sizeof(*mreq))
-}
-
-func recvmsgRaw(fd int, p, oob []byte, flags int, rsa *RawSockaddrAny) (n, oobn int, recvflags int, err error) {
-	var msg Msghdr
-	msg.Name = (*byte)(unsafe.Pointer(rsa))
-	msg.Namelen = uint32(SizeofSockaddrAny)
-	var iov Iovec
-	if len(p) > 0 {
-		iov.Base = &p[0]
-		iov.SetLen(len(p))
-	}
-	var dummy byte
-	if len(oob) > 0 {
-		if len(p) == 0 {
-			var sockType int
-			sockType, err = GetsockoptInt(fd, SOL_SOCKET, SO_TYPE)
-			if err != nil {
-				return
-			}
-			// receive at least one normal byte
-			if sockType != SOCK_DGRAM {
-				iov.Base = &dummy
-				iov.SetLen(1)
-			}
-		}
-		msg.Control = &oob[0]
-		msg.SetControllen(len(oob))
-	}
-	msg.Iov = &iov
-	msg.Iovlen = 1
-	if n, err = recvmsg(fd, &msg, flags); err != nil {
-		return
-	}
-	oobn = int(msg.Controllen)
-	recvflags = int(msg.Flags)
-	return
-}
-
-func sendmsgN(fd int, p, oob []byte, ptr unsafe.Pointer, salen _Socklen, flags int) (n int, err error) {
-	var msg Msghdr
-	msg.Name = (*byte)(ptr)
-	msg.Namelen = uint32(salen)
-	var iov Iovec
-	if len(p) > 0 {
-		iov.Base = &p[0]
-		iov.SetLen(len(p))
-	}
-	var dummy byte
-	if len(oob) > 0 {
-		if len(p) == 0 {
-			var sockType int
-			sockType, err = GetsockoptInt(fd, SOL_SOCKET, SO_TYPE)
-			if err != nil {
-				return 0, err
-			}
-			// send at least one normal byte
-			if sockType != SOCK_DGRAM {
-				iov.Base = &dummy
-				iov.SetLen(1)
-			}
-		}
-		msg.Control = &oob[0]
-		msg.SetControllen(len(oob))
-	}
-	msg.Iov = &iov
-	msg.Iovlen = 1
-	if n, err = sendmsg(fd, &msg, flags); err != nil {
-		return 0, err
-	}
-	if len(oob) > 0 && len(p) == 0 {
-		n = 0
-	}
-	return n, nil
-}
-
-// BindToDevice binds the socket associated with fd to device.
-func BindToDevice(fd int, device string) (err error) {
-	return SetsockoptString(fd, SOL_SOCKET, SO_BINDTODEVICE, device)
-}
-
-//sys	ptrace(request int, pid int, addr uintptr, data uintptr) (err error)
-
-func ptracePeek(req int, pid int, addr uintptr, out []byte) (count int, err error) {
-	// The peek requests are machine-size oriented, so we wrap it
-	// to retrieve arbitrary-length data.
-
-	// The ptrace syscall differs from glibc's ptrace.
-	// Peeks returns the word in *data, not as the return value.
-
-	var buf [sizeofPtr]byte
-
-	// Leading edge. PEEKTEXT/PEEKDATA don't require aligned
-	// access (PEEKUSER warns that it might), but if we don't
-	// align our reads, we might straddle an unmapped page
-	// boundary and not get the bytes leading up to the page
-	// boundary.
-	n := 0
-	if addr%sizeofPtr != 0 {
-		err = ptrace(req, pid, addr-addr%sizeofPtr, uintptr(unsafe.Pointer(&buf[0])))
-		if err != nil {
-			return 0, err
-		}
-		n += copy(out, buf[addr%sizeofPtr:])
-		out = out[n:]
-	}
-
-	// Remainder.
-	for len(out) > 0 {
-		// We use an internal buffer to guarantee alignment.
-		// It's not documented if this is necessary, but we're paranoid.
-		err = ptrace(req, pid, addr+uintptr(n), uintptr(unsafe.Pointer(&buf[0])))
-		if err != nil {
-			return n, err
-		}
-		copied := copy(out, buf[0:])
-		n += copied
-		out = out[copied:]
-	}
-
-	return n, nil
-}
-
-func PtracePeekText(pid int, addr uintptr, out []byte) (count int, err error) {
-	return ptracePeek(PTRACE_PEEKTEXT, pid, addr, out)
-}
-
-func PtracePeekData(pid int, addr uintptr, out []byte) (count int, err error) {
-	return ptracePeek(PTRACE_PEEKDATA, pid, addr, out)
-}
-
-func ptracePoke(pokeReq int, peekReq int, pid int, addr uintptr, data []byte) (count int, err error) {
-	// As for ptracePeek, we need to align our accesses to deal
-	// with the possibility of straddling an invalid page.
-
-	// Leading edge.
-	n := 0
-	if addr%sizeofPtr != 0 {
-		var buf [sizeofPtr]byte
-		err = ptrace(peekReq, pid, addr-addr%sizeofPtr, uintptr(unsafe.Pointer(&buf[0])))
-		if err != nil {
-			return 0, err
-		}
-		n += copy(buf[addr%sizeofPtr:], data)
-		word := *((*uintptr)(unsafe.Pointer(&buf[0])))
-		err = ptrace(pokeReq, pid, addr-addr%sizeofPtr, word)
-		if err != nil {
-			return 0, err
-		}
-		data = data[n:]
-	}
-
-	// Interior.
-	for len(data) > sizeofPtr {
-		word := *((*uintptr)(unsafe.Pointer(&data[0])))
-		err = ptrace(pokeReq, pid, addr+uintptr(n), word)
-		if err != nil {
-			return n, err
-		}
-		n += sizeofPtr
-		data = data[sizeofPtr:]
-	}
-
-	// Trailing edge.
-	if len(data) > 0 {
-		var buf [sizeofPtr]byte
-		err = ptrace(peekReq, pid, addr+uintptr(n), uintptr(unsafe.Pointer(&buf[0])))
-		if err != nil {
-			return n, err
-		}
-		copy(buf[0:], data)
-		word := *((*uintptr)(unsafe.Pointer(&buf[0])))
-		err = ptrace(pokeReq, pid, addr+uintptr(n), word)
-		if err != nil {
-			return n, err
-		}
-		n += len(data)
-	}
-
-	return n, nil
-}
-
-func PtracePokeText(pid int, addr uintptr, data []byte) (count int, err error) {
-	return ptracePoke(PTRACE_POKETEXT, PTRACE_PEEKTEXT, pid, addr, data)
-}
-
-func PtracePokeData(pid int, addr uintptr, data []byte) (count int, err error) {
-	return ptracePoke(PTRACE_POKEDATA, PTRACE_PEEKDATA, pid, addr, data)
-}
-
-func PtraceGetRegs(pid int, regsout *PtraceRegs) (err error) {
-	return ptrace(PTRACE_GETREGS, pid, 0, uintptr(unsafe.Pointer(regsout)))
-}
-
-func PtraceSetRegs(pid int, regs *PtraceRegs) (err error) {
-	return ptrace(PTRACE_SETREGS, pid, 0, uintptr(unsafe.Pointer(regs)))
-}
-
-func PtraceSetOptions(pid int, options int) (err error) {
-	return ptrace(PTRACE_SETOPTIONS, pid, 0, uintptr(options))
-}
-
-func PtraceGetEventMsg(pid int) (msg uint, err error) {
-	var data _C_long
-	err = ptrace(PTRACE_GETEVENTMSG, pid, 0, uintptr(unsafe.Pointer(&data)))
-	msg = uint(data)
-	return
-}
-
-func PtraceCont(pid int, signal int) (err error) {
-	return ptrace(PTRACE_CONT, pid, 0, uintptr(signal))
-}
-
-func PtraceSyscall(pid int, signal int) (err error) {
-	return ptrace(PTRACE_SYSCALL, pid, 0, uintptr(signal))
-}
-
-func PtraceSingleStep(pid int) (err error) { return ptrace(PTRACE_SINGLESTEP, pid, 0, 0) }
-
-func PtraceAttach(pid int) (err error) { return ptrace(PTRACE_ATTACH, pid, 0, 0) }
-
-func PtraceDetach(pid int) (err error) { return ptrace(PTRACE_DETACH, pid, 0, 0) }
-
-//sys	reboot(magic1 uint, magic2 uint, cmd int, arg string) (err error)
-
-func Reboot(cmd int) (err error) {
-	return reboot(LINUX_REBOOT_MAGIC1, LINUX_REBOOT_MAGIC2, cmd, "")
-}
-
-func ReadDirent(fd int, buf []byte) (n int, err error) {
-	return Getdents(fd, buf)
-}
-
-func direntIno(buf []byte) (uint64, bool) {
-	return readInt(buf, unsafe.Offsetof(Dirent{}.Ino), unsafe.Sizeof(Dirent{}.Ino))
-}
-
-func direntReclen(buf []byte) (uint64, bool) {
-	return readInt(buf, unsafe.Offsetof(Dirent{}.Reclen), unsafe.Sizeof(Dirent{}.Reclen))
-}
-
-func direntNamlen(buf []byte) (uint64, bool) {
-	reclen, ok := direntReclen(buf)
-	if !ok {
-		return 0, false
-	}
-	return reclen - uint64(unsafe.Offsetof(Dirent{}.Name)), true
-}
-
-//sys	mount(source string, target string, fstype string, flags uintptr, data *byte) (err error)
-
-func Mount(source string, target string, fstype string, flags uintptr, data string) (err error) {
-	// Certain file systems get rather angry and EINVAL if you give
-	// them an empty string of data, rather than NULL.
-	if data == "" {
-		return mount(source, target, fstype, flags, nil)
-	}
-	datap, err := BytePtrFromString(data)
-	if err != nil {
-		return err
-	}
-	return mount(source, target, fstype, flags, datap)
-}
-
-// Sendto
-// Recvfrom
-// Socketpair
-
-/*
- * Direct access
- */
-//sys	Acct(path string) (err error)
-//sys	Adjtimex(buf *Timex) (state int, err error)
-//sys	Chdir(path string) (err error)
-//sys	Chroot(path string) (err error)
-//sys	Close(fd int) (err error)
-//sys	Dup(oldfd int) (fd int, err error)
-//sys	Dup3(oldfd int, newfd int, flags int) (err error)
-//sysnb	EpollCreate1(flag int) (fd int, err error)
-//sysnb	EpollCtl(epfd int, op int, fd int, event *EpollEvent) (err error)
-//sys	Fallocate(fd int, mode uint32, off int64, len int64) (err error)
-//sys	Fchdir(fd int) (err error)
-//sys	Fchmod(fd int, mode uint32) (err error)
-//sys	Fchownat(dirfd int, path string, uid int, gid int, flags int) (err error)
-//sys	fcntl(fd int, cmd int, arg int) (val int, err error)
-//sys	Fdatasync(fd int) (err error)
-//sys	Flock(fd int, how int) (err error)
-//sys	Fsync(fd int) (err error)
-//sys	Getdents(fd int, buf []byte) (n int, err error) = SYS_GETDENTS64
-//sysnb	Getpgid(pid int) (pgid int, err error)
-
-func Getpgrp() (pid int) {
-	pid, _ = Getpgid(0)
-	return
-}
-
-//sysnb	Getpid() (pid int)
-//sysnb	Getppid() (ppid int)
-//sys	Getpriority(which int, who int) (prio int, err error)
-//sysnb	Getrusage(who int, rusage *Rusage) (err error)
-//sysnb	Gettid() (tid int)
-//sys	Getxattr(path string, attr string, dest []byte) (sz int, err error)
-//sys	InotifyAddWatch(fd int, pathname string, mask uint32) (watchdesc int, err error)
-//sysnb	InotifyInit1(flags int) (fd int, err error)
-//sysnb	InotifyRmWatch(fd int, watchdesc uint32) (success int, err error)
-//sysnb	Kill(pid int, sig Signal) (err error)
-//sys	Klogctl(typ int, buf []byte) (n int, err error) = SYS_SYSLOG
-//sys	Listxattr(path string, dest []byte) (sz int, err error)
-//sys	Mkdirat(dirfd int, path string, mode uint32) (err error)
-//sys	Mknodat(dirfd int, path string, mode uint32, dev int) (err error)
-//sys	Nanosleep(time *Timespec, leftover *Timespec) (err error)
-//sys	PivotRoot(newroot string, putold string) (err error) = SYS_PIVOT_ROOT
-//sysnb prlimit(pid int, resource int, newlimit *Rlimit, old *Rlimit) (err error) = SYS_PRLIMIT64
-//sys	read(fd int, p []byte) (n int, err error)
-//sys	Removexattr(path string, attr string) (err error)
-//sys	Setdomainname(p []byte) (err error)
-//sys	Sethostname(p []byte) (err error)
-//sysnb	Setpgid(pid int, pgid int) (err error)
-//sysnb	Setsid() (pid int, err error)
-//sysnb	Settimeofday(tv *Timeval) (err error)
-
-// Provided by runtime.syscall_runtime_doAllThreadsSyscall which stops the
-// world and invokes the syscall on each OS thread. Once this function returns,
-// all threads are in sync.
-//go:uintptrescapes
-func runtime_doAllThreadsSyscall(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr)
-
-// AllThreadsSyscall performs a syscall on each OS thread of the Go
-// runtime. It first invokes the syscall on one thread. Should that
-// invocation fail, it returns immediately with the error status.
-// Otherwise, it invokes the syscall on all of the remaining threads
-// in parallel. It will terminate the program if it observes any
-// invoked syscall's return value differs from that of the first
-// invocation.
-//
-// AllThreadsSyscall is intended for emulating simultaneous
-// process-wide state changes that require consistently modifying
-// per-thread state of the Go runtime.
-//
-// AllThreadsSyscall is unaware of any threads that are launched
-// explicitly by cgo linked code, so the function always returns
-// ENOTSUP in binaries that use cgo.
-//go:uintptrescapes
-func AllThreadsSyscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno) {
-	if cgo_libc_setegid != nil {
-		return minus1, minus1, ENOTSUP
-	}
-	r1, r2, errno := runtime_doAllThreadsSyscall(trap, a1, a2, a3, 0, 0, 0)
-	return r1, r2, Errno(errno)
-}
-
-// AllThreadsSyscall6 is like AllThreadsSyscall, but extended to six
-// arguments.
-//go:uintptrescapes
-func AllThreadsSyscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno) {
-	if cgo_libc_setegid != nil {
-		return minus1, minus1, ENOTSUP
-	}
-	r1, r2, errno := runtime_doAllThreadsSyscall(trap, a1, a2, a3, a4, a5, a6)
-	return r1, r2, Errno(errno)
-}
-
-// linked by runtime.cgocall.go
-//go:uintptrescapes
-func cgocaller(unsafe.Pointer, ...uintptr) uintptr
-
-var cgo_libc_setegid unsafe.Pointer // non-nil if cgo linked.
-
-const minus1 = ^uintptr(0)
-
-func Setegid(egid int) (err error) {
-	if cgo_libc_setegid == nil {
-		if _, _, e1 := AllThreadsSyscall(SYS_SETRESGID, minus1, uintptr(egid), minus1); e1 != 0 {
-			err = errnoErr(e1)
-		}
-	} else if ret := cgocaller(cgo_libc_setegid, uintptr(egid)); ret != 0 {
-		err = errnoErr(Errno(ret))
-	}
-	return
-}
-
-var cgo_libc_seteuid unsafe.Pointer // non-nil if cgo linked.
-
-func Seteuid(euid int) (err error) {
-	if cgo_libc_seteuid == nil {
-		if _, _, e1 := AllThreadsSyscall(SYS_SETRESUID, minus1, uintptr(euid), minus1); e1 != 0 {
-			err = errnoErr(e1)
-		}
-	} else if ret := cgocaller(cgo_libc_seteuid, uintptr(euid)); ret != 0 {
-		err = errnoErr(Errno(ret))
-	}
-	return
-}
-
-var cgo_libc_setgid unsafe.Pointer // non-nil if cgo linked.
-
-func Setgid(gid int) (err error) {
-	if cgo_libc_setgid == nil {
-		if _, _, e1 := AllThreadsSyscall(sys_SETGID, uintptr(gid), 0, 0); e1 != 0 {
-			err = errnoErr(e1)
-		}
-	} else if ret := cgocaller(cgo_libc_setgid, uintptr(gid)); ret != 0 {
-		err = errnoErr(Errno(ret))
-	}
-	return
-}
-
-var cgo_libc_setregid unsafe.Pointer // non-nil if cgo linked.
-
-func Setregid(rgid, egid int) (err error) {
-	if cgo_libc_setregid == nil {
-		if _, _, e1 := AllThreadsSyscall(sys_SETREGID, uintptr(rgid), uintptr(egid), 0); e1 != 0 {
-			err = errnoErr(e1)
-		}
-	} else if ret := cgocaller(cgo_libc_setregid, uintptr(rgid), uintptr(egid)); ret != 0 {
-		err = errnoErr(Errno(ret))
-	}
-	return
-}
-
-var cgo_libc_setresgid unsafe.Pointer // non-nil if cgo linked.
-
-func Setresgid(rgid, egid, sgid int) (err error) {
-	if cgo_libc_setresgid == nil {
-		if _, _, e1 := AllThreadsSyscall(sys_SETRESGID, uintptr(rgid), uintptr(egid), uintptr(sgid)); e1 != 0 {
-			err = errnoErr(e1)
-		}
-	} else if ret := cgocaller(cgo_libc_setresgid, uintptr(rgid), uintptr(egid), uintptr(sgid)); ret != 0 {
-		err = errnoErr(Errno(ret))
-	}
-	return
-}
-
-var cgo_libc_setresuid unsafe.Pointer // non-nil if cgo linked.
-
-func Setresuid(ruid, euid, suid int) (err error) {
-	if cgo_libc_setresuid == nil {
-		if _, _, e1 := AllThreadsSyscall(sys_SETRESUID, uintptr(ruid), uintptr(euid), uintptr(suid)); e1 != 0 {
-			err = errnoErr(e1)
-		}
-	} else if ret := cgocaller(cgo_libc_setresuid, uintptr(ruid), uintptr(euid), uintptr(suid)); ret != 0 {
-		err = errnoErr(Errno(ret))
-	}
-	return
-}
-
-var cgo_libc_setreuid unsafe.Pointer // non-nil if cgo linked.
-
-func Setreuid(ruid, euid int) (err error) {
-	if cgo_libc_setreuid == nil {
-		if _, _, e1 := AllThreadsSyscall(sys_SETREUID, uintptr(ruid), uintptr(euid), 0); e1 != 0 {
-			err = errnoErr(e1)
-		}
-	} else if ret := cgocaller(cgo_libc_setreuid, uintptr(ruid), uintptr(euid)); ret != 0 {
-		err = errnoErr(Errno(ret))
-	}
-	return
-}
-
-var cgo_libc_setuid unsafe.Pointer // non-nil if cgo linked.
-
-func Setuid(uid int) (err error) {
-	if cgo_libc_setuid == nil {
-		if _, _, e1 := AllThreadsSyscall(sys_SETUID, uintptr(uid), 0, 0); e1 != 0 {
-			err = errnoErr(e1)
-		}
-	} else if ret := cgocaller(cgo_libc_setuid, uintptr(uid)); ret != 0 {
-		err = errnoErr(Errno(ret))
-	}
-	return
-}
-
-//sys	Setpriority(which int, who int, prio int) (err error)
-//sys	Setxattr(path string, attr string, data []byte, flags int) (err error)
-//sys	Sync()
-//sysnb	Sysinfo(info *Sysinfo_t) (err error)
-//sys	Tee(rfd int, wfd int, len int, flags int) (n int64, err error)
-//sysnb	Tgkill(tgid int, tid int, sig Signal) (err error)
-//sysnb	Times(tms *Tms) (ticks uintptr, err error)
-//sysnb	Umask(mask int) (oldmask int)
-//sysnb	Uname(buf *Utsname) (err error)
-//sys	Unmount(target string, flags int) (err error) = SYS_UMOUNT2
-//sys	Unshare(flags int) (err error)
-//sys	write(fd int, p []byte) (n int, err error)
-//sys	exitThread(code int) (err error) = SYS_EXIT
-//sys	readlen(fd int, p *byte, np int) (n int, err error) = SYS_READ
-//sys	writelen(fd int, p *byte, np int) (n int, err error) = SYS_WRITE
-
-// mmap varies by architecture; see syscall_linux_*.go.
-//sys	munmap(addr uintptr, length uintptr) (err error)
-
-var mapper = &mmapper{
-	active: make(map[*byte][]byte),
-	mmap:   mmap,
-	munmap: munmap,
-}
-
-func Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error) {
-	return mapper.Mmap(fd, offset, length, prot, flags)
-}
-
-func Munmap(b []byte) (err error) {
-	return mapper.Munmap(b)
-}
-
-//sys	Madvise(b []byte, advice int) (err error)
-//sys	Mprotect(b []byte, prot int) (err error)
-//sys	Mlock(b []byte) (err error)
-//sys	Munlock(b []byte) (err error)
-//sys	Mlockall(flags int) (err error)
-//sys	Munlockall() (err error)
diff --git a/contrib/go/_std_1.18/src/syscall/syscall_linux_amd64.go b/contrib/go/_std_1.18/src/syscall/syscall_linux_amd64.go
deleted file mode 100644
index 26b40ffe9b..0000000000
--- a/contrib/go/_std_1.18/src/syscall/syscall_linux_amd64.go
+++ /dev/null
@@ -1,123 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package syscall
-
-const _SYS_setgroups = SYS_SETGROUPS
-
-//sys	Dup2(oldfd int, newfd int) (err error)
-//sysnb	EpollCreate(size int) (fd int, err error)
-//sys	Fchown(fd int, uid int, gid int) (err error)
-//sys	Fstat(fd int, stat *Stat_t) (err error)
-//sys	Fstatfs(fd int, buf *Statfs_t) (err error)
-//sys	Ftruncate(fd int, length int64) (err error)
-//sysnb	Getegid() (egid int)
-//sysnb	Geteuid() (euid int)
-//sysnb	Getgid() (gid int)
-//sysnb	Getrlimit(resource int, rlim *Rlimit) (err error)
-//sysnb	Getuid() (uid int)
-//sysnb	InotifyInit() (fd int, err error)
-//sys	Ioperm(from int, num int, on int) (err error)
-//sys	Iopl(level int) (err error)
-//sys	Listen(s int, n int) (err error)
-//sys	Pause() (err error)
-//sys	Pread(fd int, p []byte, offset int64) (n int, err error) = SYS_PREAD64
-//sys	Pwrite(fd int, p []byte, offset int64) (n int, err error) = SYS_PWRITE64
-//sys	Renameat(olddirfd int, oldpath string, newdirfd int, newpath string) (err error)
-//sys	Seek(fd int, offset int64, whence int) (off int64, err error) = SYS_LSEEK
-//sys	Select(nfd int, r *FdSet, w *FdSet, e *FdSet, timeout *Timeval) (n int, err error)
-//sys	sendfile(outfd int, infd int, offset *int64, count int) (written int, err error)
-//sys	Setfsgid(gid int) (err error)
-//sys	Setfsuid(uid int) (err error)
-//sysnb	Setrlimit(resource int, rlim *Rlimit) (err error)
-//sys	Shutdown(fd int, how int) (err error)
-//sys	Splice(rfd int, roff *int64, wfd int, woff *int64, len int, flags int) (n int64, err error)
-//sys	Statfs(path string, buf *Statfs_t) (err error)
-//sys	SyncFileRange(fd int, off int64, n int64, flags int) (err error)
-//sys	Truncate(path string, length int64) (err error)
-//sys	Ustat(dev int, ubuf *Ustat_t) (err error)
-//sys	accept(s int, rsa *RawSockaddrAny, addrlen *_Socklen) (fd int, err error)
-//sys	accept4(s int, rsa *RawSockaddrAny, addrlen *_Socklen, flags int) (fd int, err error)
-//sys	bind(s int, addr unsafe.Pointer, addrlen _Socklen) (err error)
-//sys	connect(s int, addr unsafe.Pointer, addrlen _Socklen) (err error)
-//sys	fstatat(fd int, path string, stat *Stat_t, flags int) (err error) = SYS_NEWFSTATAT
-//sysnb	getgroups(n int, list *_Gid_t) (nn int, err error)
-//sys	getsockopt(s int, level int, name int, val unsafe.Pointer, vallen *_Socklen) (err error)
-//sys	setsockopt(s int, level int, name int, val unsafe.Pointer, vallen uintptr) (err error)
-//sysnb	socket(domain int, typ int, proto int) (fd int, err error)
-//sysnb	socketpair(domain int, typ int, proto int, fd *[2]int32) (err error)
-//sysnb	getpeername(fd int, rsa *RawSockaddrAny, addrlen *_Socklen) (err error)
-//sysnb	getsockname(fd int, rsa *RawSockaddrAny, addrlen *_Socklen) (err error)
-//sys	recvfrom(fd int, p []byte, flags int, from *RawSockaddrAny, fromlen *_Socklen) (n int, err error)
-//sys	sendto(s int, buf []byte, flags int, to unsafe.Pointer, addrlen _Socklen) (err error)
-//sys	recvmsg(s int, msg *Msghdr, flags int) (n int, err error)
-//sys	sendmsg(s int, msg *Msghdr, flags int) (n int, err error)
-//sys	mmap(addr uintptr, length uintptr, prot int, flags int, fd int, offset int64) (xaddr uintptr, err error)
-//sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
-
-func Stat(path string, stat *Stat_t) (err error) {
-	return fstatat(_AT_FDCWD, path, stat, 0)
-}
-
-func Lchown(path string, uid int, gid int) (err error) {
-	return Fchownat(_AT_FDCWD, path, uid, gid, _AT_SYMLINK_NOFOLLOW)
-}
-
-func Lstat(path string, stat *Stat_t) (err error) {
-	return fstatat(_AT_FDCWD, path, stat, _AT_SYMLINK_NOFOLLOW)
-}
-
-//sys	futimesat(dirfd int, path string, times *[2]Timeval) (err error)
-
-//go:noescape
-func gettimeofday(tv *Timeval) (err Errno)
-
-func Gettimeofday(tv *Timeval) (err error) {
-	errno := gettimeofday(tv)
-	if errno != 0 {
-		return errno
-	}
-	return nil
-}
-
-func Time(t *Time_t) (tt Time_t, err error) {
-	var tv Timeval
-	errno := gettimeofday(&tv)
-	if errno != 0 {
-		return 0, errno
-	}
-	if t != nil {
-		*t = Time_t(tv.Sec)
-	}
-	return Time_t(tv.Sec), nil
-}
-
-//sys	Utime(path string, buf *Utimbuf) (err error)
-//sys	utimes(path string, times *[2]Timeval) (err error)
-
-func setTimespec(sec, nsec int64) Timespec {
-	return Timespec{Sec: sec, Nsec: nsec}
-}
-
-func setTimeval(sec, usec int64) Timeval {
-	return Timeval{Sec: sec, Usec: usec}
-}
-
-func (r *PtraceRegs) PC() uint64 { return r.Rip }
-
-func (r *PtraceRegs) SetPC(pc uint64) { r.Rip = pc }
-
-func (iov *Iovec) SetLen(length int) {
-	iov.Len = uint64(length)
-}
-
-func (msghdr *Msghdr) SetControllen(length int) {
-	msghdr.Controllen = uint64(length)
-}
-
-func (cmsg *Cmsghdr) SetLen(length int) {
-	cmsg.Len = uint64(length)
-}
-
-func rawVforkSyscall(trap, a1 uintptr) (r1 uintptr, err Errno)
diff --git a/contrib/go/_std_1.18/src/syscall/syscall_unix.go b/contrib/go/_std_1.18/src/syscall/syscall_unix.go
deleted file mode 100644
index 5ee938115d..0000000000
--- a/contrib/go/_std_1.18/src/syscall/syscall_unix.go
+++ /dev/null
@@ -1,487 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
-
-package syscall
-
-import (
-	"internal/itoa"
-	"internal/oserror"
-	"internal/race"
-	"internal/unsafeheader"
-	"runtime"
-	"sync"
-	"unsafe"
-)
-
-var (
-	Stdin  = 0
-	Stdout = 1
-	Stderr = 2
-)
-
-const (
-	darwin64Bit = (runtime.GOOS == "darwin" || runtime.GOOS == "ios") && sizeofPtr == 8
-	netbsd32Bit = runtime.GOOS == "netbsd" && sizeofPtr == 4
-)
-
-func Syscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno)
-func Syscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno)
-func RawSyscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno)
-func RawSyscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno)
-
-// clen returns the index of the first NULL byte in n or len(n) if n contains no NULL byte.
-func clen(n []byte) int {
-	for i := 0; i < len(n); i++ {
-		if n[i] == 0 {
-			return i
-		}
-	}
-	return len(n)
-}
-
-// Mmap manager, for use by operating system-specific implementations.
-
-type mmapper struct {
-	sync.Mutex
-	active map[*byte][]byte // active mappings; key is last byte in mapping
-	mmap   func(addr, length uintptr, prot, flags, fd int, offset int64) (uintptr, error)
-	munmap func(addr uintptr, length uintptr) error
-}
-
-func (m *mmapper) Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error) {
-	if length <= 0 {
-		return nil, EINVAL
-	}
-
-	// Map the requested memory.
-	addr, errno := m.mmap(0, uintptr(length), prot, flags, fd, offset)
-	if errno != nil {
-		return nil, errno
-	}
-
-	// Use unsafe to turn addr into a []byte.
-	var b []byte
-	hdr := (*unsafeheader.Slice)(unsafe.Pointer(&b))
-	hdr.Data = unsafe.Pointer(addr)
-	hdr.Cap = length
-	hdr.Len = length
-
-	// Register mapping in m and return it.
-	p := &b[cap(b)-1]
-	m.Lock()
-	defer m.Unlock()
-	m.active[p] = b
-	return b, nil
-}
-
-func (m *mmapper) Munmap(data []byte) (err error) {
-	if len(data) == 0 || len(data) != cap(data) {
-		return EINVAL
-	}
-
-	// Find the base of the mapping.
-	p := &data[cap(data)-1]
-	m.Lock()
-	defer m.Unlock()
-	b := m.active[p]
-	if b == nil || &b[0] != &data[0] {
-		return EINVAL
-	}
-
-	// Unmap the memory and update m.
-	if errno := m.munmap(uintptr(unsafe.Pointer(&b[0])), uintptr(len(b))); errno != nil {
-		return errno
-	}
-	delete(m.active, p)
-	return nil
-}
-
-// An Errno is an unsigned number describing an error condition.
-// It implements the error interface. The zero Errno is by convention
-// a non-error, so code to convert from Errno to error should use:
-//	err = nil
-//	if errno != 0 {
-//		err = errno
-//	}
-//
-// Errno values can be tested against error values from the os package
-// using errors.Is. For example:
-//
-//	_, _, err := syscall.Syscall(...)
-//	if errors.Is(err, fs.ErrNotExist) ...
-type Errno uintptr
-
-func (e Errno) Error() string {
-	if 0 <= int(e) && int(e) < len(errors) {
-		s := errors[e]
-		if s != "" {
-			return s
-		}
-	}
-	return "errno " + itoa.Itoa(int(e))
-}
-
-func (e Errno) Is(target error) bool {
-	switch target {
-	case oserror.ErrPermission:
-		return e == EACCES || e == EPERM
-	case oserror.ErrExist:
-		return e == EEXIST || e == ENOTEMPTY
-	case oserror.ErrNotExist:
-		return e == ENOENT
-	}
-	return false
-}
-
-func (e Errno) Temporary() bool {
-	return e == EINTR || e == EMFILE || e == ENFILE || e.Timeout()
-}
-
-func (e Errno) Timeout() bool {
-	return e == EAGAIN || e == EWOULDBLOCK || e == ETIMEDOUT
-}
-
-// Do the interface allocations only once for common
-// Errno values.
-var (
-	errEAGAIN error = EAGAIN
-	errEINVAL error = EINVAL
-	errENOENT error = ENOENT
-)
-
-// errnoErr returns common boxed Errno values, to prevent
-// allocations at runtime.
-func errnoErr(e Errno) error {
-	switch e {
-	case 0:
-		return nil
-	case EAGAIN:
-		return errEAGAIN
-	case EINVAL:
-		return errEINVAL
-	case ENOENT:
-		return errENOENT
-	}
-	return e
-}
-
-// A Signal is a number describing a process signal.
-// It implements the os.Signal interface.
-type Signal int
-
-func (s Signal) Signal() {}
-
-func (s Signal) String() string {
-	if 0 <= s && int(s) < len(signals) {
-		str := signals[s]
-		if str != "" {
-			return str
-		}
-	}
-	return "signal " + itoa.Itoa(int(s))
-}
-
-func Read(fd int, p []byte) (n int, err error) {
-	n, err = read(fd, p)
-	if race.Enabled {
-		if n > 0 {
-			race.WriteRange(unsafe.Pointer(&p[0]), n)
-		}
-		if err == nil {
-			race.Acquire(unsafe.Pointer(&ioSync))
-		}
-	}
-	if msanenabled && n > 0 {
-		msanWrite(unsafe.Pointer(&p[0]), n)
-	}
-	if asanenabled && n > 0 {
-		asanWrite(unsafe.Pointer(&p[0]), n)
-	}
-	return
-}
-
-func Write(fd int, p []byte) (n int, err error) {
-	if race.Enabled {
-		race.ReleaseMerge(unsafe.Pointer(&ioSync))
-	}
-	if faketime && (fd == 1 || fd == 2) {
-		n = faketimeWrite(fd, p)
-		if n < 0 {
-			n, err = 0, errnoErr(Errno(-n))
-		}
-	} else {
-		n, err = write(fd, p)
-	}
-	if race.Enabled && n > 0 {
-		race.ReadRange(unsafe.Pointer(&p[0]), n)
-	}
-	if msanenabled && n > 0 {
-		msanRead(unsafe.Pointer(&p[0]), n)
-	}
-	if asanenabled && n > 0 {
-		asanRead(unsafe.Pointer(&p[0]), n)
-	}
-	return
-}
-
-// For testing: clients can set this flag to force
-// creation of IPv6 sockets to return EAFNOSUPPORT.
-var SocketDisableIPv6 bool
-
-type Sockaddr interface {
-	sockaddr() (ptr unsafe.Pointer, len _Socklen, err error) // lowercase; only we can define Sockaddrs
-}
-
-type SockaddrInet4 struct {
-	Port int
-	Addr [4]byte
-	raw  RawSockaddrInet4
-}
-
-type SockaddrInet6 struct {
-	Port   int
-	ZoneId uint32
-	Addr   [16]byte
-	raw    RawSockaddrInet6
-}
-
-type SockaddrUnix struct {
-	Name string
-	raw  RawSockaddrUnix
-}
-
-func Bind(fd int, sa Sockaddr) (err error) {
-	ptr, n, err := sa.sockaddr()
-	if err != nil {
-		return err
-	}
-	return bind(fd, ptr, n)
-}
-
-func Connect(fd int, sa Sockaddr) (err error) {
-	ptr, n, err := sa.sockaddr()
-	if err != nil {
-		return err
-	}
-	return connect(fd, ptr, n)
-}
-
-func Getpeername(fd int) (sa Sockaddr, err error) {
-	var rsa RawSockaddrAny
-	var len _Socklen = SizeofSockaddrAny
-	if err = getpeername(fd, &rsa, &len); err != nil {
-		return
-	}
-	return anyToSockaddr(&rsa)
-}
-
-func GetsockoptInt(fd, level, opt int) (value int, err error) {
-	var n int32
-	vallen := _Socklen(4)
-	err = getsockopt(fd, level, opt, unsafe.Pointer(&n), &vallen)
-	return int(n), err
-}
-
-func Recvfrom(fd int, p []byte, flags int) (n int, from Sockaddr, err error) {
-	var rsa RawSockaddrAny
-	var len _Socklen = SizeofSockaddrAny
-	if n, err = recvfrom(fd, p, flags, &rsa, &len); err != nil {
-		return
-	}
-	if rsa.Addr.Family != AF_UNSPEC {
-		from, err = anyToSockaddr(&rsa)
-	}
-	return
-}
-
-func recvfromInet4(fd int, p []byte, flags int, from *SockaddrInet4) (n int, err error) {
-	var rsa RawSockaddrAny
-	var socklen _Socklen = SizeofSockaddrAny
-	if n, err = recvfrom(fd, p, flags, &rsa, &socklen); err != nil {
-		return
-	}
-	pp := (*RawSockaddrInet4)(unsafe.Pointer(&rsa))
-	port := (*[2]byte)(unsafe.Pointer(&pp.Port))
-	from.Port = int(port[0])<<8 + int(port[1])
-	from.Addr = pp.Addr
-	return
-}
-
-func recvfromInet6(fd int, p []byte, flags int, from *SockaddrInet6) (n int, err error) {
-	var rsa RawSockaddrAny
-	var socklen _Socklen = SizeofSockaddrAny
-	if n, err = recvfrom(fd, p, flags, &rsa, &socklen); err != nil {
-		return
-	}
-	pp := (*RawSockaddrInet6)(unsafe.Pointer(&rsa))
-	port := (*[2]byte)(unsafe.Pointer(&pp.Port))
-	from.Port = int(port[0])<<8 + int(port[1])
-	from.ZoneId = pp.Scope_id
-	from.Addr = pp.Addr
-	return
-}
-
-func recvmsgInet4(fd int, p, oob []byte, flags int, from *SockaddrInet4) (n, oobn int, recvflags int, err error) {
-	var rsa RawSockaddrAny
-	n, oobn, recvflags, err = recvmsgRaw(fd, p, oob, flags, &rsa)
-	if err != nil {
-		return
-	}
-	pp := (*RawSockaddrInet4)(unsafe.Pointer(&rsa))
-	port := (*[2]byte)(unsafe.Pointer(&pp.Port))
-	from.Port = int(port[0])<<8 + int(port[1])
-	from.Addr = pp.Addr
-	return
-}
-
-func recvmsgInet6(fd int, p, oob []byte, flags int, from *SockaddrInet6) (n, oobn int, recvflags int, err error) {
-	var rsa RawSockaddrAny
-	n, oobn, recvflags, err = recvmsgRaw(fd, p, oob, flags, &rsa)
-	if err != nil {
-		return
-	}
-	pp := (*RawSockaddrInet6)(unsafe.Pointer(&rsa))
-	port := (*[2]byte)(unsafe.Pointer(&pp.Port))
-	from.Port = int(port[0])<<8 + int(port[1])
-	from.ZoneId = pp.Scope_id
-	from.Addr = pp.Addr
-	return
-}
-
-func Recvmsg(fd int, p, oob []byte, flags int) (n, oobn int, recvflags int, from Sockaddr, err error) {
-	var rsa RawSockaddrAny
-	n, oobn, recvflags, err = recvmsgRaw(fd, p, oob, flags, &rsa)
-	// source address is only specified if the socket is unconnected
-	if rsa.Addr.Family != AF_UNSPEC {
-		from, err = anyToSockaddr(&rsa)
-	}
-	return
-}
-
-func Sendmsg(fd int, p, oob []byte, to Sockaddr, flags int) (err error) {
-	_, err = SendmsgN(fd, p, oob, to, flags)
-	return
-}
-
-func SendmsgN(fd int, p, oob []byte, to Sockaddr, flags int) (n int, err error) {
-	var ptr unsafe.Pointer
-	var salen _Socklen
-	if to != nil {
-		ptr, salen, err = to.sockaddr()
-		if err != nil {
-			return 0, err
-		}
-	}
-	return sendmsgN(fd, p, oob, ptr, salen, flags)
-}
-
-func sendmsgNInet4(fd int, p, oob []byte, to *SockaddrInet4, flags int) (n int, err error) {
-	ptr, salen, err := to.sockaddr()
-	if err != nil {
-		return 0, err
-	}
-	return sendmsgN(fd, p, oob, ptr, salen, flags)
-}
-
-func sendmsgNInet6(fd int, p, oob []byte, to *SockaddrInet6, flags int) (n int, err error) {
-	ptr, salen, err := to.sockaddr()
-	if err != nil {
-		return 0, err
-	}
-	return sendmsgN(fd, p, oob, ptr, salen, flags)
-}
-
-func sendtoInet4(fd int, p []byte, flags int, to *SockaddrInet4) (err error) {
-	ptr, n, err := to.sockaddr()
-	if err != nil {
-		return err
-	}
-	return sendto(fd, p, flags, ptr, n)
-}
-
-func sendtoInet6(fd int, p []byte, flags int, to *SockaddrInet6) (err error) {
-	ptr, n, err := to.sockaddr()
-	if err != nil {
-		return err
-	}
-	return sendto(fd, p, flags, ptr, n)
-}
-
-func Sendto(fd int, p []byte, flags int, to Sockaddr) (err error) {
-	ptr, n, err := to.sockaddr()
-	if err != nil {
-		return err
-	}
-	return sendto(fd, p, flags, ptr, n)
-}
-
-func SetsockoptByte(fd, level, opt int, value byte) (err error) {
-	return setsockopt(fd, level, opt, unsafe.Pointer(&value), 1)
-}
-
-func SetsockoptInt(fd, level, opt int, value int) (err error) {
-	var n = int32(value)
-	return setsockopt(fd, level, opt, unsafe.Pointer(&n), 4)
-}
-
-func SetsockoptInet4Addr(fd, level, opt int, value [4]byte) (err error) {
-	return setsockopt(fd, level, opt, unsafe.Pointer(&value[0]), 4)
-}
-
-func SetsockoptIPMreq(fd, level, opt int, mreq *IPMreq) (err error) {
-	return setsockopt(fd, level, opt, unsafe.Pointer(mreq), SizeofIPMreq)
-}
-
-func SetsockoptIPv6Mreq(fd, level, opt int, mreq *IPv6Mreq) (err error) {
-	return setsockopt(fd, level, opt, unsafe.Pointer(mreq), SizeofIPv6Mreq)
-}
-
-func SetsockoptICMPv6Filter(fd, level, opt int, filter *ICMPv6Filter) error {
-	return setsockopt(fd, level, opt, unsafe.Pointer(filter), SizeofICMPv6Filter)
-}
-
-func SetsockoptLinger(fd, level, opt int, l *Linger) (err error) {
-	return setsockopt(fd, level, opt, unsafe.Pointer(l), SizeofLinger)
-}
-
-func SetsockoptString(fd, level, opt int, s string) (err error) {
-	var p unsafe.Pointer
-	if len(s) > 0 {
-		p = unsafe.Pointer(&[]byte(s)[0])
-	}
-	return setsockopt(fd, level, opt, p, uintptr(len(s)))
-}
-
-func SetsockoptTimeval(fd, level, opt int, tv *Timeval) (err error) {
-	return setsockopt(fd, level, opt, unsafe.Pointer(tv), unsafe.Sizeof(*tv))
-}
-
-func Socket(domain, typ, proto int) (fd int, err error) {
-	if domain == AF_INET6 && SocketDisableIPv6 {
-		return -1, EAFNOSUPPORT
-	}
-	fd, err = socket(domain, typ, proto)
-	return
-}
-
-func Socketpair(domain, typ, proto int) (fd [2]int, err error) {
-	var fdx [2]int32
-	err = socketpair(domain, typ, proto, &fdx)
-	if err == nil {
-		fd[0] = int(fdx[0])
-		fd[1] = int(fdx[1])
-	}
-	return
-}
-
-func Sendfile(outfd int, infd int, offset *int64, count int) (written int, err error) {
-	if race.Enabled {
-		race.ReleaseMerge(unsafe.Pointer(&ioSync))
-	}
-	return sendfile(outfd, infd, offset, count)
-}
-
-var ioSync int64
diff --git a/contrib/go/_std_1.18/src/syscall/timestruct.go b/contrib/go/_std_1.18/src/syscall/timestruct.go
deleted file mode 100644
index 7cf4be45b1..0000000000
--- a/contrib/go/_std_1.18/src/syscall/timestruct.go
+++ /dev/null
@@ -1,36 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris
-
-package syscall
-
-// TimespecToNSec returns the time stored in ts as nanoseconds.
-func TimespecToNsec(ts Timespec) int64 { return ts.Nano() }
-
-// NsecToTimespec converts a number of nanoseconds into a Timespec.
-func NsecToTimespec(nsec int64) Timespec {
-	sec := nsec / 1e9
-	nsec = nsec % 1e9
-	if nsec < 0 {
-		nsec += 1e9
-		sec--
-	}
-	return setTimespec(sec, nsec)
-}
-
-// TimevalToNsec returns the time stored in tv as nanoseconds.
-func TimevalToNsec(tv Timeval) int64 { return tv.Nano() }
-
-// NsecToTimeval converts a number of nanoseconds into a Timeval.
-func NsecToTimeval(nsec int64) Timeval {
-	nsec += 999 // round up to microsecond
-	usec := nsec % 1e9 / 1e3
-	sec := nsec / 1e9
-	if usec < 0 {
-		usec += 1e6
-		sec--
-	}
-	return setTimeval(sec, usec)
-}
diff --git a/contrib/go/_std_1.18/src/syscall/zsyscall_darwin_amd64.go b/contrib/go/_std_1.18/src/syscall/zsyscall_darwin_amd64.go
deleted file mode 100644
index 0ccdaf2d0e..0000000000
--- a/contrib/go/_std_1.18/src/syscall/zsyscall_darwin_amd64.go
+++ /dev/null
@@ -1,2004 +0,0 @@
-// mksyscall.pl -darwin -tags darwin,amd64 syscall_bsd.go syscall_darwin.go syscall_darwin_amd64.go
-// Code generated by the command above; DO NOT EDIT.
-
-//go:build darwin && amd64
-
-package syscall
-
-import "unsafe"
-import "internal/abi"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func getgroups(ngid int, gid *_Gid_t) (n int, err error) {
-	r0, _, e1 := rawSyscall(abi.FuncPCABI0(libc_getgroups_trampoline), uintptr(ngid), uintptr(unsafe.Pointer(gid)), 0)
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_getgroups_trampoline()
-
-//go:cgo_import_dynamic libc_getgroups getgroups "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func setgroups(ngid int, gid *_Gid_t) (err error) {
-	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_setgroups_trampoline), uintptr(ngid), uintptr(unsafe.Pointer(gid)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_setgroups_trampoline()
-
-//go:cgo_import_dynamic libc_setgroups setgroups "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func wait4(pid int, wstatus *_C_int, options int, rusage *Rusage) (wpid int, err error) {
-	r0, _, e1 := syscall6(abi.FuncPCABI0(libc_wait4_trampoline), uintptr(pid), uintptr(unsafe.Pointer(wstatus)), uintptr(options), uintptr(unsafe.Pointer(rusage)), 0, 0)
-	wpid = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_wait4_trampoline()
-
-//go:cgo_import_dynamic libc_wait4 wait4 "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func accept(s int, rsa *RawSockaddrAny, addrlen *_Socklen) (fd int, err error) {
-	r0, _, e1 := syscall(abi.FuncPCABI0(libc_accept_trampoline), uintptr(s), uintptr(unsafe.Pointer(rsa)), uintptr(unsafe.Pointer(addrlen)))
-	fd = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_accept_trampoline()
-
-//go:cgo_import_dynamic libc_accept accept "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func bind(s int, addr unsafe.Pointer, addrlen _Socklen) (err error) {
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_bind_trampoline), uintptr(s), uintptr(addr), uintptr(addrlen))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_bind_trampoline()
-
-//go:cgo_import_dynamic libc_bind bind "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func connect(s int, addr unsafe.Pointer, addrlen _Socklen) (err error) {
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_connect_trampoline), uintptr(s), uintptr(addr), uintptr(addrlen))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_connect_trampoline()
-
-//go:cgo_import_dynamic libc_connect connect "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func socket(domain int, typ int, proto int) (fd int, err error) {
-	r0, _, e1 := rawSyscall(abi.FuncPCABI0(libc_socket_trampoline), uintptr(domain), uintptr(typ), uintptr(proto))
-	fd = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_socket_trampoline()
-
-//go:cgo_import_dynamic libc_socket socket "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func getsockopt(s int, level int, name int, val unsafe.Pointer, vallen *_Socklen) (err error) {
-	_, _, e1 := syscall6(abi.FuncPCABI0(libc_getsockopt_trampoline), uintptr(s), uintptr(level), uintptr(name), uintptr(val), uintptr(unsafe.Pointer(vallen)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_getsockopt_trampoline()
-
-//go:cgo_import_dynamic libc_getsockopt getsockopt "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func setsockopt(s int, level int, name int, val unsafe.Pointer, vallen uintptr) (err error) {
-	_, _, e1 := syscall6(abi.FuncPCABI0(libc_setsockopt_trampoline), uintptr(s), uintptr(level), uintptr(name), uintptr(val), uintptr(vallen), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_setsockopt_trampoline()
-
-//go:cgo_import_dynamic libc_setsockopt setsockopt "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func getpeername(fd int, rsa *RawSockaddrAny, addrlen *_Socklen) (err error) {
-	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_getpeername_trampoline), uintptr(fd), uintptr(unsafe.Pointer(rsa)), uintptr(unsafe.Pointer(addrlen)))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_getpeername_trampoline()
-
-//go:cgo_import_dynamic libc_getpeername getpeername "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func getsockname(fd int, rsa *RawSockaddrAny, addrlen *_Socklen) (err error) {
-	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_getsockname_trampoline), uintptr(fd), uintptr(unsafe.Pointer(rsa)), uintptr(unsafe.Pointer(addrlen)))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_getsockname_trampoline()
-
-//go:cgo_import_dynamic libc_getsockname getsockname "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Shutdown(s int, how int) (err error) {
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_shutdown_trampoline), uintptr(s), uintptr(how), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_shutdown_trampoline()
-
-//go:cgo_import_dynamic libc_shutdown shutdown "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func socketpair(domain int, typ int, proto int, fd *[2]int32) (err error) {
-	_, _, e1 := rawSyscall6(abi.FuncPCABI0(libc_socketpair_trampoline), uintptr(domain), uintptr(typ), uintptr(proto), uintptr(unsafe.Pointer(fd)), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_socketpair_trampoline()
-
-//go:cgo_import_dynamic libc_socketpair socketpair "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func recvfrom(fd int, p []byte, flags int, from *RawSockaddrAny, fromlen *_Socklen) (n int, err error) {
-	var _p0 unsafe.Pointer
-	if len(p) > 0 {
-		_p0 = unsafe.Pointer(&p[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	r0, _, e1 := syscall6(abi.FuncPCABI0(libc_recvfrom_trampoline), uintptr(fd), uintptr(_p0), uintptr(len(p)), uintptr(flags), uintptr(unsafe.Pointer(from)), uintptr(unsafe.Pointer(fromlen)))
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_recvfrom_trampoline()
-
-//go:cgo_import_dynamic libc_recvfrom recvfrom "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func sendto(s int, buf []byte, flags int, to unsafe.Pointer, addrlen _Socklen) (err error) {
-	var _p0 unsafe.Pointer
-	if len(buf) > 0 {
-		_p0 = unsafe.Pointer(&buf[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	_, _, e1 := syscall6(abi.FuncPCABI0(libc_sendto_trampoline), uintptr(s), uintptr(_p0), uintptr(len(buf)), uintptr(flags), uintptr(to), uintptr(addrlen))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_sendto_trampoline()
-
-//go:cgo_import_dynamic libc_sendto sendto "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func recvmsg(s int, msg *Msghdr, flags int) (n int, err error) {
-	r0, _, e1 := syscall(abi.FuncPCABI0(libc_recvmsg_trampoline), uintptr(s), uintptr(unsafe.Pointer(msg)), uintptr(flags))
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_recvmsg_trampoline()
-
-//go:cgo_import_dynamic libc_recvmsg recvmsg "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func sendmsg(s int, msg *Msghdr, flags int) (n int, err error) {
-	r0, _, e1 := syscall(abi.FuncPCABI0(libc_sendmsg_trampoline), uintptr(s), uintptr(unsafe.Pointer(msg)), uintptr(flags))
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_sendmsg_trampoline()
-
-//go:cgo_import_dynamic libc_sendmsg sendmsg "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func kevent(kq int, change unsafe.Pointer, nchange int, event unsafe.Pointer, nevent int, timeout *Timespec) (n int, err error) {
-	r0, _, e1 := syscall6(abi.FuncPCABI0(libc_kevent_trampoline), uintptr(kq), uintptr(change), uintptr(nchange), uintptr(event), uintptr(nevent), uintptr(unsafe.Pointer(timeout)))
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_kevent_trampoline()
-
-//go:cgo_import_dynamic libc_kevent kevent "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func utimes(path string, timeval *[2]Timeval) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_utimes_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(timeval)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_utimes_trampoline()
-
-//go:cgo_import_dynamic libc_utimes utimes "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func futimes(fd int, timeval *[2]Timeval) (err error) {
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_futimes_trampoline), uintptr(fd), uintptr(unsafe.Pointer(timeval)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_futimes_trampoline()
-
-//go:cgo_import_dynamic libc_futimes futimes "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func fcntl(fd int, cmd int, arg int) (val int, err error) {
-	r0, _, e1 := syscall(abi.FuncPCABI0(libc_fcntl_trampoline), uintptr(fd), uintptr(cmd), uintptr(arg))
-	val = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_fcntl_trampoline()
-
-//go:cgo_import_dynamic libc_fcntl fcntl "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func pipe(p *[2]int32) (err error) {
-	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_pipe_trampoline), uintptr(unsafe.Pointer(p)), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_pipe_trampoline()
-
-//go:cgo_import_dynamic libc_pipe pipe "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func utimensat(dirfd int, path string, times *[2]Timespec, flags int) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall6(abi.FuncPCABI0(libc_utimensat_trampoline), uintptr(dirfd), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(times)), uintptr(flags), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_utimensat_trampoline()
-
-//go:cgo_import_dynamic libc_utimensat utimensat "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func kill(pid int, signum int, posix int) (err error) {
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_kill_trampoline), uintptr(pid), uintptr(signum), uintptr(posix))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_kill_trampoline()
-
-//go:cgo_import_dynamic libc_kill kill "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Access(path string, mode uint32) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_access_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(mode), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_access_trampoline()
-
-//go:cgo_import_dynamic libc_access access "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Adjtime(delta *Timeval, olddelta *Timeval) (err error) {
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_adjtime_trampoline), uintptr(unsafe.Pointer(delta)), uintptr(unsafe.Pointer(olddelta)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_adjtime_trampoline()
-
-//go:cgo_import_dynamic libc_adjtime adjtime "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Chdir(path string) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_chdir_trampoline), uintptr(unsafe.Pointer(_p0)), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_chdir_trampoline()
-
-//go:cgo_import_dynamic libc_chdir chdir "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Chflags(path string, flags int) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_chflags_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(flags), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_chflags_trampoline()
-
-//go:cgo_import_dynamic libc_chflags chflags "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Chmod(path string, mode uint32) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_chmod_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(mode), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_chmod_trampoline()
-
-//go:cgo_import_dynamic libc_chmod chmod "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Chown(path string, uid int, gid int) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_chown_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(uid), uintptr(gid))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_chown_trampoline()
-
-//go:cgo_import_dynamic libc_chown chown "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Chroot(path string) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_chroot_trampoline), uintptr(unsafe.Pointer(_p0)), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_chroot_trampoline()
-
-//go:cgo_import_dynamic libc_chroot chroot "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Close(fd int) (err error) {
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_close_trampoline), uintptr(fd), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_close_trampoline()
-
-//go:cgo_import_dynamic libc_close close "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func closedir(dir uintptr) (err error) {
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_closedir_trampoline), uintptr(dir), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_closedir_trampoline()
-
-//go:cgo_import_dynamic libc_closedir closedir "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Dup(fd int) (nfd int, err error) {
-	r0, _, e1 := syscall(abi.FuncPCABI0(libc_dup_trampoline), uintptr(fd), 0, 0)
-	nfd = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_dup_trampoline()
-
-//go:cgo_import_dynamic libc_dup dup "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Dup2(from int, to int) (err error) {
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_dup2_trampoline), uintptr(from), uintptr(to), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_dup2_trampoline()
-
-//go:cgo_import_dynamic libc_dup2 dup2 "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Exchangedata(path1 string, path2 string, options int) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path1)
-	if err != nil {
-		return
-	}
-	var _p1 *byte
-	_p1, err = BytePtrFromString(path2)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_exchangedata_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(_p1)), uintptr(options))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_exchangedata_trampoline()
-
-//go:cgo_import_dynamic libc_exchangedata exchangedata "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Fchdir(fd int) (err error) {
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_fchdir_trampoline), uintptr(fd), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_fchdir_trampoline()
-
-//go:cgo_import_dynamic libc_fchdir fchdir "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Fchflags(fd int, flags int) (err error) {
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_fchflags_trampoline), uintptr(fd), uintptr(flags), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_fchflags_trampoline()
-
-//go:cgo_import_dynamic libc_fchflags fchflags "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Fchmod(fd int, mode uint32) (err error) {
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_fchmod_trampoline), uintptr(fd), uintptr(mode), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_fchmod_trampoline()
-
-//go:cgo_import_dynamic libc_fchmod fchmod "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Fchown(fd int, uid int, gid int) (err error) {
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_fchown_trampoline), uintptr(fd), uintptr(uid), uintptr(gid))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_fchown_trampoline()
-
-//go:cgo_import_dynamic libc_fchown fchown "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Flock(fd int, how int) (err error) {
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_flock_trampoline), uintptr(fd), uintptr(how), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_flock_trampoline()
-
-//go:cgo_import_dynamic libc_flock flock "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Fpathconf(fd int, name int) (val int, err error) {
-	r0, _, e1 := syscall(abi.FuncPCABI0(libc_fpathconf_trampoline), uintptr(fd), uintptr(name), 0)
-	val = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_fpathconf_trampoline()
-
-//go:cgo_import_dynamic libc_fpathconf fpathconf "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Fsync(fd int) (err error) {
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_fsync_trampoline), uintptr(fd), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_fsync_trampoline()
-
-//go:cgo_import_dynamic libc_fsync fsync "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Ftruncate(fd int, length int64) (err error) {
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_ftruncate_trampoline), uintptr(fd), uintptr(length), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_ftruncate_trampoline()
-
-//go:cgo_import_dynamic libc_ftruncate ftruncate "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Getdtablesize() (size int) {
-	r0, _, _ := syscall(abi.FuncPCABI0(libc_getdtablesize_trampoline), 0, 0, 0)
-	size = int(r0)
-	return
-}
-
-func libc_getdtablesize_trampoline()
-
-//go:cgo_import_dynamic libc_getdtablesize getdtablesize "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Getegid() (egid int) {
-	r0, _, _ := rawSyscall(abi.FuncPCABI0(libc_getegid_trampoline), 0, 0, 0)
-	egid = int(r0)
-	return
-}
-
-func libc_getegid_trampoline()
-
-//go:cgo_import_dynamic libc_getegid getegid "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Geteuid() (uid int) {
-	r0, _, _ := rawSyscall(abi.FuncPCABI0(libc_geteuid_trampoline), 0, 0, 0)
-	uid = int(r0)
-	return
-}
-
-func libc_geteuid_trampoline()
-
-//go:cgo_import_dynamic libc_geteuid geteuid "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Getgid() (gid int) {
-	r0, _, _ := rawSyscall(abi.FuncPCABI0(libc_getgid_trampoline), 0, 0, 0)
-	gid = int(r0)
-	return
-}
-
-func libc_getgid_trampoline()
-
-//go:cgo_import_dynamic libc_getgid getgid "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Getpgid(pid int) (pgid int, err error) {
-	r0, _, e1 := rawSyscall(abi.FuncPCABI0(libc_getpgid_trampoline), uintptr(pid), 0, 0)
-	pgid = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_getpgid_trampoline()
-
-//go:cgo_import_dynamic libc_getpgid getpgid "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Getpgrp() (pgrp int) {
-	r0, _, _ := rawSyscall(abi.FuncPCABI0(libc_getpgrp_trampoline), 0, 0, 0)
-	pgrp = int(r0)
-	return
-}
-
-func libc_getpgrp_trampoline()
-
-//go:cgo_import_dynamic libc_getpgrp getpgrp "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Getpid() (pid int) {
-	r0, _, _ := rawSyscall(abi.FuncPCABI0(libc_getpid_trampoline), 0, 0, 0)
-	pid = int(r0)
-	return
-}
-
-func libc_getpid_trampoline()
-
-//go:cgo_import_dynamic libc_getpid getpid "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Getppid() (ppid int) {
-	r0, _, _ := rawSyscall(abi.FuncPCABI0(libc_getppid_trampoline), 0, 0, 0)
-	ppid = int(r0)
-	return
-}
-
-func libc_getppid_trampoline()
-
-//go:cgo_import_dynamic libc_getppid getppid "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Getpriority(which int, who int) (prio int, err error) {
-	r0, _, e1 := syscall(abi.FuncPCABI0(libc_getpriority_trampoline), uintptr(which), uintptr(who), 0)
-	prio = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_getpriority_trampoline()
-
-//go:cgo_import_dynamic libc_getpriority getpriority "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Getrlimit(which int, lim *Rlimit) (err error) {
-	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_getrlimit_trampoline), uintptr(which), uintptr(unsafe.Pointer(lim)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_getrlimit_trampoline()
-
-//go:cgo_import_dynamic libc_getrlimit getrlimit "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Getrusage(who int, rusage *Rusage) (err error) {
-	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_getrusage_trampoline), uintptr(who), uintptr(unsafe.Pointer(rusage)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_getrusage_trampoline()
-
-//go:cgo_import_dynamic libc_getrusage getrusage "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Getsid(pid int) (sid int, err error) {
-	r0, _, e1 := rawSyscall(abi.FuncPCABI0(libc_getsid_trampoline), uintptr(pid), 0, 0)
-	sid = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_getsid_trampoline()
-
-//go:cgo_import_dynamic libc_getsid getsid "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Getuid() (uid int) {
-	r0, _, _ := rawSyscall(abi.FuncPCABI0(libc_getuid_trampoline), 0, 0, 0)
-	uid = int(r0)
-	return
-}
-
-func libc_getuid_trampoline()
-
-//go:cgo_import_dynamic libc_getuid getuid "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Issetugid() (tainted bool) {
-	r0, _, _ := rawSyscall(abi.FuncPCABI0(libc_issetugid_trampoline), 0, 0, 0)
-	tainted = bool(r0 != 0)
-	return
-}
-
-func libc_issetugid_trampoline()
-
-//go:cgo_import_dynamic libc_issetugid issetugid "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Kqueue() (fd int, err error) {
-	r0, _, e1 := syscall(abi.FuncPCABI0(libc_kqueue_trampoline), 0, 0, 0)
-	fd = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_kqueue_trampoline()
-
-//go:cgo_import_dynamic libc_kqueue kqueue "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Lchown(path string, uid int, gid int) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_lchown_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(uid), uintptr(gid))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_lchown_trampoline()
-
-//go:cgo_import_dynamic libc_lchown lchown "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Link(path string, link string) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	var _p1 *byte
-	_p1, err = BytePtrFromString(link)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_link_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(_p1)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_link_trampoline()
-
-//go:cgo_import_dynamic libc_link link "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Listen(s int, backlog int) (err error) {
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_listen_trampoline), uintptr(s), uintptr(backlog), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_listen_trampoline()
-
-//go:cgo_import_dynamic libc_listen listen "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Mkdir(path string, mode uint32) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_mkdir_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(mode), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_mkdir_trampoline()
-
-//go:cgo_import_dynamic libc_mkdir mkdir "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Mkfifo(path string, mode uint32) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_mkfifo_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(mode), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_mkfifo_trampoline()
-
-//go:cgo_import_dynamic libc_mkfifo mkfifo "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Mknod(path string, mode uint32, dev int) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_mknod_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(mode), uintptr(dev))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_mknod_trampoline()
-
-//go:cgo_import_dynamic libc_mknod mknod "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Mlock(b []byte) (err error) {
-	var _p0 unsafe.Pointer
-	if len(b) > 0 {
-		_p0 = unsafe.Pointer(&b[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_mlock_trampoline), uintptr(_p0), uintptr(len(b)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_mlock_trampoline()
-
-//go:cgo_import_dynamic libc_mlock mlock "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Mlockall(flags int) (err error) {
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_mlockall_trampoline), uintptr(flags), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_mlockall_trampoline()
-
-//go:cgo_import_dynamic libc_mlockall mlockall "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Mprotect(b []byte, prot int) (err error) {
-	var _p0 unsafe.Pointer
-	if len(b) > 0 {
-		_p0 = unsafe.Pointer(&b[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_mprotect_trampoline), uintptr(_p0), uintptr(len(b)), uintptr(prot))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_mprotect_trampoline()
-
-//go:cgo_import_dynamic libc_mprotect mprotect "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Munlock(b []byte) (err error) {
-	var _p0 unsafe.Pointer
-	if len(b) > 0 {
-		_p0 = unsafe.Pointer(&b[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_munlock_trampoline), uintptr(_p0), uintptr(len(b)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_munlock_trampoline()
-
-//go:cgo_import_dynamic libc_munlock munlock "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Munlockall() (err error) {
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_munlockall_trampoline), 0, 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_munlockall_trampoline()
-
-//go:cgo_import_dynamic libc_munlockall munlockall "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Open(path string, mode int, perm uint32) (fd int, err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	r0, _, e1 := syscall(abi.FuncPCABI0(libc_open_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(mode), uintptr(perm))
-	fd = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_open_trampoline()
-
-//go:cgo_import_dynamic libc_open open "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Pathconf(path string, name int) (val int, err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	r0, _, e1 := syscall(abi.FuncPCABI0(libc_pathconf_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(name), 0)
-	val = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_pathconf_trampoline()
-
-//go:cgo_import_dynamic libc_pathconf pathconf "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Pread(fd int, p []byte, offset int64) (n int, err error) {
-	var _p0 unsafe.Pointer
-	if len(p) > 0 {
-		_p0 = unsafe.Pointer(&p[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	r0, _, e1 := syscall6(abi.FuncPCABI0(libc_pread_trampoline), uintptr(fd), uintptr(_p0), uintptr(len(p)), uintptr(offset), 0, 0)
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_pread_trampoline()
-
-//go:cgo_import_dynamic libc_pread pread "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Pwrite(fd int, p []byte, offset int64) (n int, err error) {
-	var _p0 unsafe.Pointer
-	if len(p) > 0 {
-		_p0 = unsafe.Pointer(&p[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	r0, _, e1 := syscall6(abi.FuncPCABI0(libc_pwrite_trampoline), uintptr(fd), uintptr(_p0), uintptr(len(p)), uintptr(offset), 0, 0)
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_pwrite_trampoline()
-
-//go:cgo_import_dynamic libc_pwrite pwrite "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func read(fd int, p []byte) (n int, err error) {
-	var _p0 unsafe.Pointer
-	if len(p) > 0 {
-		_p0 = unsafe.Pointer(&p[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	r0, _, e1 := syscall(abi.FuncPCABI0(libc_read_trampoline), uintptr(fd), uintptr(_p0), uintptr(len(p)))
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_read_trampoline()
-
-//go:cgo_import_dynamic libc_read read "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func readdir_r(dir uintptr, entry *Dirent, result **Dirent) (res Errno) {
-	r0, _, _ := syscall(abi.FuncPCABI0(libc_readdir_r_trampoline), uintptr(dir), uintptr(unsafe.Pointer(entry)), uintptr(unsafe.Pointer(result)))
-	res = Errno(r0)
-	return
-}
-
-func libc_readdir_r_trampoline()
-
-//go:cgo_import_dynamic libc_readdir_r readdir_r "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Readlink(path string, buf []byte) (n int, err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	var _p1 unsafe.Pointer
-	if len(buf) > 0 {
-		_p1 = unsafe.Pointer(&buf[0])
-	} else {
-		_p1 = unsafe.Pointer(&_zero)
-	}
-	r0, _, e1 := syscall(abi.FuncPCABI0(libc_readlink_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(_p1), uintptr(len(buf)))
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_readlink_trampoline()
-
-//go:cgo_import_dynamic libc_readlink readlink "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Rename(from string, to string) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(from)
-	if err != nil {
-		return
-	}
-	var _p1 *byte
-	_p1, err = BytePtrFromString(to)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_rename_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(_p1)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_rename_trampoline()
-
-//go:cgo_import_dynamic libc_rename rename "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Revoke(path string) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_revoke_trampoline), uintptr(unsafe.Pointer(_p0)), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_revoke_trampoline()
-
-//go:cgo_import_dynamic libc_revoke revoke "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Rmdir(path string) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_rmdir_trampoline), uintptr(unsafe.Pointer(_p0)), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_rmdir_trampoline()
-
-//go:cgo_import_dynamic libc_rmdir rmdir "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Seek(fd int, offset int64, whence int) (newoffset int64, err error) {
-	r0, _, e1 := syscallX(abi.FuncPCABI0(libc_lseek_trampoline), uintptr(fd), uintptr(offset), uintptr(whence))
-	newoffset = int64(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_lseek_trampoline()
-
-//go:cgo_import_dynamic libc_lseek lseek "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Select(n int, r *FdSet, w *FdSet, e *FdSet, timeout *Timeval) (err error) {
-	_, _, e1 := syscall6(abi.FuncPCABI0(libc_select_trampoline), uintptr(n), uintptr(unsafe.Pointer(r)), uintptr(unsafe.Pointer(w)), uintptr(unsafe.Pointer(e)), uintptr(unsafe.Pointer(timeout)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_select_trampoline()
-
-//go:cgo_import_dynamic libc_select select "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Setegid(egid int) (err error) {
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_setegid_trampoline), uintptr(egid), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_setegid_trampoline()
-
-//go:cgo_import_dynamic libc_setegid setegid "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Seteuid(euid int) (err error) {
-	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_seteuid_trampoline), uintptr(euid), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_seteuid_trampoline()
-
-//go:cgo_import_dynamic libc_seteuid seteuid "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Setgid(gid int) (err error) {
-	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_setgid_trampoline), uintptr(gid), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_setgid_trampoline()
-
-//go:cgo_import_dynamic libc_setgid setgid "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Setlogin(name string) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(name)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_setlogin_trampoline), uintptr(unsafe.Pointer(_p0)), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_setlogin_trampoline()
-
-//go:cgo_import_dynamic libc_setlogin setlogin "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Setpgid(pid int, pgid int) (err error) {
-	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_setpgid_trampoline), uintptr(pid), uintptr(pgid), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_setpgid_trampoline()
-
-//go:cgo_import_dynamic libc_setpgid setpgid "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Setpriority(which int, who int, prio int) (err error) {
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_setpriority_trampoline), uintptr(which), uintptr(who), uintptr(prio))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_setpriority_trampoline()
-
-//go:cgo_import_dynamic libc_setpriority setpriority "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Setprivexec(flag int) (err error) {
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_setprivexec_trampoline), uintptr(flag), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_setprivexec_trampoline()
-
-//go:cgo_import_dynamic libc_setprivexec setprivexec "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Setregid(rgid int, egid int) (err error) {
-	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_setregid_trampoline), uintptr(rgid), uintptr(egid), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_setregid_trampoline()
-
-//go:cgo_import_dynamic libc_setregid setregid "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Setreuid(ruid int, euid int) (err error) {
-	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_setreuid_trampoline), uintptr(ruid), uintptr(euid), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_setreuid_trampoline()
-
-//go:cgo_import_dynamic libc_setreuid setreuid "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Setrlimit(which int, lim *Rlimit) (err error) {
-	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_setrlimit_trampoline), uintptr(which), uintptr(unsafe.Pointer(lim)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_setrlimit_trampoline()
-
-//go:cgo_import_dynamic libc_setrlimit setrlimit "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Setsid() (pid int, err error) {
-	r0, _, e1 := rawSyscall(abi.FuncPCABI0(libc_setsid_trampoline), 0, 0, 0)
-	pid = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_setsid_trampoline()
-
-//go:cgo_import_dynamic libc_setsid setsid "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Settimeofday(tp *Timeval) (err error) {
-	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_settimeofday_trampoline), uintptr(unsafe.Pointer(tp)), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_settimeofday_trampoline()
-
-//go:cgo_import_dynamic libc_settimeofday settimeofday "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Setuid(uid int) (err error) {
-	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_setuid_trampoline), uintptr(uid), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_setuid_trampoline()
-
-//go:cgo_import_dynamic libc_setuid setuid "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Symlink(path string, link string) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	var _p1 *byte
-	_p1, err = BytePtrFromString(link)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_symlink_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(_p1)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_symlink_trampoline()
-
-//go:cgo_import_dynamic libc_symlink symlink "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Sync() (err error) {
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_sync_trampoline), 0, 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_sync_trampoline()
-
-//go:cgo_import_dynamic libc_sync sync "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Truncate(path string, length int64) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_truncate_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(length), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_truncate_trampoline()
-
-//go:cgo_import_dynamic libc_truncate truncate "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Umask(newmask int) (oldmask int) {
-	r0, _, _ := syscall(abi.FuncPCABI0(libc_umask_trampoline), uintptr(newmask), 0, 0)
-	oldmask = int(r0)
-	return
-}
-
-func libc_umask_trampoline()
-
-//go:cgo_import_dynamic libc_umask umask "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Undelete(path string) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_undelete_trampoline), uintptr(unsafe.Pointer(_p0)), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_undelete_trampoline()
-
-//go:cgo_import_dynamic libc_undelete undelete "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Unlink(path string) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_unlink_trampoline), uintptr(unsafe.Pointer(_p0)), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_unlink_trampoline()
-
-//go:cgo_import_dynamic libc_unlink unlink "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Unmount(path string, flags int) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_unmount_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(flags), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_unmount_trampoline()
-
-//go:cgo_import_dynamic libc_unmount unmount "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func write(fd int, p []byte) (n int, err error) {
-	var _p0 unsafe.Pointer
-	if len(p) > 0 {
-		_p0 = unsafe.Pointer(&p[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	r0, _, e1 := syscall(abi.FuncPCABI0(libc_write_trampoline), uintptr(fd), uintptr(_p0), uintptr(len(p)))
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_write_trampoline()
-
-//go:cgo_import_dynamic libc_write write "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func writev(fd int, iovecs []Iovec) (cnt uintptr, err error) {
-	var _p0 unsafe.Pointer
-	if len(iovecs) > 0 {
-		_p0 = unsafe.Pointer(&iovecs[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	r0, _, e1 := syscallX(abi.FuncPCABI0(libc_writev_trampoline), uintptr(fd), uintptr(_p0), uintptr(len(iovecs)))
-	cnt = uintptr(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_writev_trampoline()
-
-//go:cgo_import_dynamic libc_writev writev "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func mmap(addr uintptr, length uintptr, prot int, flag int, fd int, pos int64) (ret uintptr, err error) {
-	r0, _, e1 := syscall6X(abi.FuncPCABI0(libc_mmap_trampoline), uintptr(addr), uintptr(length), uintptr(prot), uintptr(flag), uintptr(fd), uintptr(pos))
-	ret = uintptr(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_mmap_trampoline()
-
-//go:cgo_import_dynamic libc_mmap mmap "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func munmap(addr uintptr, length uintptr) (err error) {
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_munmap_trampoline), uintptr(addr), uintptr(length), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_munmap_trampoline()
-
-//go:cgo_import_dynamic libc_munmap munmap "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func fork() (pid int, err error) {
-	r0, _, e1 := rawSyscall(abi.FuncPCABI0(libc_fork_trampoline), 0, 0, 0)
-	pid = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_fork_trampoline()
-
-//go:cgo_import_dynamic libc_fork fork "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func ioctl(fd int, req int, arg int) (err error) {
-	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_ioctl_trampoline), uintptr(fd), uintptr(req), uintptr(arg))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_ioctl_trampoline()
-
-//go:cgo_import_dynamic libc_ioctl ioctl "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func ioctlPtr(fd int, req uint, arg unsafe.Pointer) (err error) {
-	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_ioctl_trampoline), uintptr(fd), uintptr(req), uintptr(arg))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func execve(path *byte, argv **byte, envp **byte) (err error) {
-	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_execve_trampoline), uintptr(unsafe.Pointer(path)), uintptr(unsafe.Pointer(argv)), uintptr(unsafe.Pointer(envp)))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_execve_trampoline()
-
-//go:cgo_import_dynamic libc_execve execve "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func exit(res int) (err error) {
-	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_exit_trampoline), uintptr(res), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_exit_trampoline()
-
-//go:cgo_import_dynamic libc_exit exit "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func sysctl(mib []_C_int, old *byte, oldlen *uintptr, new *byte, newlen uintptr) (err error) {
-	var _p0 unsafe.Pointer
-	if len(mib) > 0 {
-		_p0 = unsafe.Pointer(&mib[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	_, _, e1 := syscall6(abi.FuncPCABI0(libc_sysctl_trampoline), uintptr(_p0), uintptr(len(mib)), uintptr(unsafe.Pointer(old)), uintptr(unsafe.Pointer(oldlen)), uintptr(unsafe.Pointer(new)), uintptr(newlen))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_sysctl_trampoline()
-
-//go:cgo_import_dynamic libc_sysctl sysctl "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func fcntlPtr(fd int, cmd int, arg unsafe.Pointer) (val int, err error) {
-	r0, _, e1 := syscall(abi.FuncPCABI0(libc_fcntl_trampoline), uintptr(fd), uintptr(cmd), uintptr(arg))
-	val = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func unlinkat(fd int, path string, flags int) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_unlinkat_trampoline), uintptr(fd), uintptr(unsafe.Pointer(_p0)), uintptr(flags))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_unlinkat_trampoline()
-
-//go:cgo_import_dynamic libc_unlinkat unlinkat "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func openat(fd int, path string, flags int, perm uint32) (fdret int, err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	r0, _, e1 := syscall6(abi.FuncPCABI0(libc_openat_trampoline), uintptr(fd), uintptr(unsafe.Pointer(_p0)), uintptr(flags), uintptr(perm), 0, 0)
-	fdret = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_openat_trampoline()
-
-//go:cgo_import_dynamic libc_openat openat "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func getcwd(buf []byte) (n int, err error) {
-	var _p0 unsafe.Pointer
-	if len(buf) > 0 {
-		_p0 = unsafe.Pointer(&buf[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	r0, _, e1 := syscall(abi.FuncPCABI0(libc_getcwd_trampoline), uintptr(_p0), uintptr(len(buf)), 0)
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_getcwd_trampoline()
-
-//go:cgo_import_dynamic libc_getcwd getcwd "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Fstat(fd int, stat *Stat_t) (err error) {
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_fstat64_trampoline), uintptr(fd), uintptr(unsafe.Pointer(stat)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_fstat64_trampoline()
-
-//go:cgo_import_dynamic libc_fstat64 fstat64 "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Fstatfs(fd int, stat *Statfs_t) (err error) {
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_fstatfs64_trampoline), uintptr(fd), uintptr(unsafe.Pointer(stat)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_fstatfs64_trampoline()
-
-//go:cgo_import_dynamic libc_fstatfs64 fstatfs64 "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Gettimeofday(tp *Timeval) (err error) {
-	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_gettimeofday_trampoline), uintptr(unsafe.Pointer(tp)), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_gettimeofday_trampoline()
-
-//go:cgo_import_dynamic libc_gettimeofday gettimeofday "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Lstat(path string, stat *Stat_t) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_lstat64_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(stat)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_lstat64_trampoline()
-
-//go:cgo_import_dynamic libc_lstat64 lstat64 "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Stat(path string, stat *Stat_t) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_stat64_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(stat)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_stat64_trampoline()
-
-//go:cgo_import_dynamic libc_stat64 stat64 "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Statfs(path string, stat *Statfs_t) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall(abi.FuncPCABI0(libc_statfs64_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(stat)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_statfs64_trampoline()
-
-//go:cgo_import_dynamic libc_statfs64 statfs64 "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func fstatat(fd int, path string, stat *Stat_t, flags int) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := syscall6(abi.FuncPCABI0(libc_fstatat64_trampoline), uintptr(fd), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(stat)), uintptr(flags), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_fstatat64_trampoline()
-
-//go:cgo_import_dynamic libc_fstatat64 fstatat64 "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-//go:nosplit
-func ptrace1(request int, pid int, addr uintptr, data uintptr) (err error) {
-	_, _, e1 := syscall6(abi.FuncPCABI0(libc_ptrace_trampoline), uintptr(request), uintptr(pid), uintptr(addr), uintptr(data), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_ptrace_trampoline()
-
-//go:cgo_import_dynamic libc_ptrace ptrace "/usr/lib/libSystem.B.dylib"
diff --git a/contrib/go/_std_1.18/src/syscall/zsyscall_linux_amd64.go b/contrib/go/_std_1.18/src/syscall/zsyscall_linux_amd64.go
deleted file mode 100644
index 2059271324..0000000000
--- a/contrib/go/_std_1.18/src/syscall/zsyscall_linux_amd64.go
+++ /dev/null
@@ -1,1655 +0,0 @@
-// mksyscall.pl -tags linux,amd64 syscall_linux.go syscall_linux_amd64.go
-// Code generated by the command above; DO NOT EDIT.
-
-//go:build linux && amd64
-
-package syscall
-
-import "unsafe"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func faccessat(dirfd int, path string, mode uint32) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := Syscall(SYS_FACCESSAT, uintptr(dirfd), uintptr(unsafe.Pointer(_p0)), uintptr(mode))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func fchmodat(dirfd int, path string, mode uint32) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := Syscall(SYS_FCHMODAT, uintptr(dirfd), uintptr(unsafe.Pointer(_p0)), uintptr(mode))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func linkat(olddirfd int, oldpath string, newdirfd int, newpath string, flags int) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(oldpath)
-	if err != nil {
-		return
-	}
-	var _p1 *byte
-	_p1, err = BytePtrFromString(newpath)
-	if err != nil {
-		return
-	}
-	_, _, e1 := Syscall6(SYS_LINKAT, uintptr(olddirfd), uintptr(unsafe.Pointer(_p0)), uintptr(newdirfd), uintptr(unsafe.Pointer(_p1)), uintptr(flags), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func openat(dirfd int, path string, flags int, mode uint32) (fd int, err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	r0, _, e1 := Syscall6(SYS_OPENAT, uintptr(dirfd), uintptr(unsafe.Pointer(_p0)), uintptr(flags), uintptr(mode), 0, 0)
-	fd = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func pipe2(p *[2]_C_int, flags int) (err error) {
-	_, _, e1 := RawSyscall(SYS_PIPE2, uintptr(unsafe.Pointer(p)), uintptr(flags), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func readlinkat(dirfd int, path string, buf []byte) (n int, err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	var _p1 unsafe.Pointer
-	if len(buf) > 0 {
-		_p1 = unsafe.Pointer(&buf[0])
-	} else {
-		_p1 = unsafe.Pointer(&_zero)
-	}
-	r0, _, e1 := Syscall6(SYS_READLINKAT, uintptr(dirfd), uintptr(unsafe.Pointer(_p0)), uintptr(_p1), uintptr(len(buf)), 0, 0)
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func symlinkat(oldpath string, newdirfd int, newpath string) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(oldpath)
-	if err != nil {
-		return
-	}
-	var _p1 *byte
-	_p1, err = BytePtrFromString(newpath)
-	if err != nil {
-		return
-	}
-	_, _, e1 := Syscall(SYS_SYMLINKAT, uintptr(unsafe.Pointer(_p0)), uintptr(newdirfd), uintptr(unsafe.Pointer(_p1)))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func unlinkat(dirfd int, path string, flags int) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := Syscall(SYS_UNLINKAT, uintptr(dirfd), uintptr(unsafe.Pointer(_p0)), uintptr(flags))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func utimensat(dirfd int, path string, times *[2]Timespec, flag int) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := Syscall6(SYS_UTIMENSAT, uintptr(dirfd), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(times)), uintptr(flag), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Getcwd(buf []byte) (n int, err error) {
-	var _p0 unsafe.Pointer
-	if len(buf) > 0 {
-		_p0 = unsafe.Pointer(&buf[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	r0, _, e1 := Syscall(SYS_GETCWD, uintptr(_p0), uintptr(len(buf)), 0)
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func wait4(pid int, wstatus *_C_int, options int, rusage *Rusage) (wpid int, err error) {
-	r0, _, e1 := Syscall6(SYS_WAIT4, uintptr(pid), uintptr(unsafe.Pointer(wstatus)), uintptr(options), uintptr(unsafe.Pointer(rusage)), 0, 0)
-	wpid = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func ptrace(request int, pid int, addr uintptr, data uintptr) (err error) {
-	_, _, e1 := Syscall6(SYS_PTRACE, uintptr(request), uintptr(pid), uintptr(addr), uintptr(data), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func reboot(magic1 uint, magic2 uint, cmd int, arg string) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(arg)
-	if err != nil {
-		return
-	}
-	_, _, e1 := Syscall6(SYS_REBOOT, uintptr(magic1), uintptr(magic2), uintptr(cmd), uintptr(unsafe.Pointer(_p0)), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func mount(source string, target string, fstype string, flags uintptr, data *byte) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(source)
-	if err != nil {
-		return
-	}
-	var _p1 *byte
-	_p1, err = BytePtrFromString(target)
-	if err != nil {
-		return
-	}
-	var _p2 *byte
-	_p2, err = BytePtrFromString(fstype)
-	if err != nil {
-		return
-	}
-	_, _, e1 := Syscall6(SYS_MOUNT, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(_p1)), uintptr(unsafe.Pointer(_p2)), uintptr(flags), uintptr(unsafe.Pointer(data)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Acct(path string) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := Syscall(SYS_ACCT, uintptr(unsafe.Pointer(_p0)), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Adjtimex(buf *Timex) (state int, err error) {
-	r0, _, e1 := Syscall(SYS_ADJTIMEX, uintptr(unsafe.Pointer(buf)), 0, 0)
-	state = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Chdir(path string) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := Syscall(SYS_CHDIR, uintptr(unsafe.Pointer(_p0)), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Chroot(path string) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := Syscall(SYS_CHROOT, uintptr(unsafe.Pointer(_p0)), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Close(fd int) (err error) {
-	_, _, e1 := Syscall(SYS_CLOSE, uintptr(fd), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Dup(oldfd int) (fd int, err error) {
-	r0, _, e1 := Syscall(SYS_DUP, uintptr(oldfd), 0, 0)
-	fd = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Dup3(oldfd int, newfd int, flags int) (err error) {
-	_, _, e1 := Syscall(SYS_DUP3, uintptr(oldfd), uintptr(newfd), uintptr(flags))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func EpollCreate1(flag int) (fd int, err error) {
-	r0, _, e1 := RawSyscall(SYS_EPOLL_CREATE1, uintptr(flag), 0, 0)
-	fd = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func EpollCtl(epfd int, op int, fd int, event *EpollEvent) (err error) {
-	_, _, e1 := RawSyscall6(SYS_EPOLL_CTL, uintptr(epfd), uintptr(op), uintptr(fd), uintptr(unsafe.Pointer(event)), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Fallocate(fd int, mode uint32, off int64, len int64) (err error) {
-	_, _, e1 := Syscall6(SYS_FALLOCATE, uintptr(fd), uintptr(mode), uintptr(off), uintptr(len), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Fchdir(fd int) (err error) {
-	_, _, e1 := Syscall(SYS_FCHDIR, uintptr(fd), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Fchmod(fd int, mode uint32) (err error) {
-	_, _, e1 := Syscall(SYS_FCHMOD, uintptr(fd), uintptr(mode), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Fchownat(dirfd int, path string, uid int, gid int, flags int) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := Syscall6(SYS_FCHOWNAT, uintptr(dirfd), uintptr(unsafe.Pointer(_p0)), uintptr(uid), uintptr(gid), uintptr(flags), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func fcntl(fd int, cmd int, arg int) (val int, err error) {
-	r0, _, e1 := Syscall(SYS_FCNTL, uintptr(fd), uintptr(cmd), uintptr(arg))
-	val = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Fdatasync(fd int) (err error) {
-	_, _, e1 := Syscall(SYS_FDATASYNC, uintptr(fd), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Flock(fd int, how int) (err error) {
-	_, _, e1 := Syscall(SYS_FLOCK, uintptr(fd), uintptr(how), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Fsync(fd int) (err error) {
-	_, _, e1 := Syscall(SYS_FSYNC, uintptr(fd), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Getdents(fd int, buf []byte) (n int, err error) {
-	var _p0 unsafe.Pointer
-	if len(buf) > 0 {
-		_p0 = unsafe.Pointer(&buf[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	r0, _, e1 := Syscall(SYS_GETDENTS64, uintptr(fd), uintptr(_p0), uintptr(len(buf)))
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Getpgid(pid int) (pgid int, err error) {
-	r0, _, e1 := RawSyscall(SYS_GETPGID, uintptr(pid), 0, 0)
-	pgid = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Getpid() (pid int) {
-	r0, _ := rawSyscallNoError(SYS_GETPID, 0, 0, 0)
-	pid = int(r0)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Getppid() (ppid int) {
-	r0, _ := rawSyscallNoError(SYS_GETPPID, 0, 0, 0)
-	ppid = int(r0)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Getpriority(which int, who int) (prio int, err error) {
-	r0, _, e1 := Syscall(SYS_GETPRIORITY, uintptr(which), uintptr(who), 0)
-	prio = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Getrusage(who int, rusage *Rusage) (err error) {
-	_, _, e1 := RawSyscall(SYS_GETRUSAGE, uintptr(who), uintptr(unsafe.Pointer(rusage)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Gettid() (tid int) {
-	r0, _ := rawSyscallNoError(SYS_GETTID, 0, 0, 0)
-	tid = int(r0)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Getxattr(path string, attr string, dest []byte) (sz int, err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	var _p1 *byte
-	_p1, err = BytePtrFromString(attr)
-	if err != nil {
-		return
-	}
-	var _p2 unsafe.Pointer
-	if len(dest) > 0 {
-		_p2 = unsafe.Pointer(&dest[0])
-	} else {
-		_p2 = unsafe.Pointer(&_zero)
-	}
-	r0, _, e1 := Syscall6(SYS_GETXATTR, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(_p1)), uintptr(_p2), uintptr(len(dest)), 0, 0)
-	sz = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func InotifyAddWatch(fd int, pathname string, mask uint32) (watchdesc int, err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(pathname)
-	if err != nil {
-		return
-	}
-	r0, _, e1 := Syscall(SYS_INOTIFY_ADD_WATCH, uintptr(fd), uintptr(unsafe.Pointer(_p0)), uintptr(mask))
-	watchdesc = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func InotifyInit1(flags int) (fd int, err error) {
-	r0, _, e1 := RawSyscall(SYS_INOTIFY_INIT1, uintptr(flags), 0, 0)
-	fd = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func InotifyRmWatch(fd int, watchdesc uint32) (success int, err error) {
-	r0, _, e1 := RawSyscall(SYS_INOTIFY_RM_WATCH, uintptr(fd), uintptr(watchdesc), 0)
-	success = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Kill(pid int, sig Signal) (err error) {
-	_, _, e1 := RawSyscall(SYS_KILL, uintptr(pid), uintptr(sig), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Klogctl(typ int, buf []byte) (n int, err error) {
-	var _p0 unsafe.Pointer
-	if len(buf) > 0 {
-		_p0 = unsafe.Pointer(&buf[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	r0, _, e1 := Syscall(SYS_SYSLOG, uintptr(typ), uintptr(_p0), uintptr(len(buf)))
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Listxattr(path string, dest []byte) (sz int, err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	var _p1 unsafe.Pointer
-	if len(dest) > 0 {
-		_p1 = unsafe.Pointer(&dest[0])
-	} else {
-		_p1 = unsafe.Pointer(&_zero)
-	}
-	r0, _, e1 := Syscall(SYS_LISTXATTR, uintptr(unsafe.Pointer(_p0)), uintptr(_p1), uintptr(len(dest)))
-	sz = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Mkdirat(dirfd int, path string, mode uint32) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := Syscall(SYS_MKDIRAT, uintptr(dirfd), uintptr(unsafe.Pointer(_p0)), uintptr(mode))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Mknodat(dirfd int, path string, mode uint32, dev int) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := Syscall6(SYS_MKNODAT, uintptr(dirfd), uintptr(unsafe.Pointer(_p0)), uintptr(mode), uintptr(dev), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Nanosleep(time *Timespec, leftover *Timespec) (err error) {
-	_, _, e1 := Syscall(SYS_NANOSLEEP, uintptr(unsafe.Pointer(time)), uintptr(unsafe.Pointer(leftover)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func PivotRoot(newroot string, putold string) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(newroot)
-	if err != nil {
-		return
-	}
-	var _p1 *byte
-	_p1, err = BytePtrFromString(putold)
-	if err != nil {
-		return
-	}
-	_, _, e1 := Syscall(SYS_PIVOT_ROOT, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(_p1)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func prlimit(pid int, resource int, newlimit *Rlimit, old *Rlimit) (err error) {
-	_, _, e1 := RawSyscall6(SYS_PRLIMIT64, uintptr(pid), uintptr(resource), uintptr(unsafe.Pointer(newlimit)), uintptr(unsafe.Pointer(old)), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func read(fd int, p []byte) (n int, err error) {
-	var _p0 unsafe.Pointer
-	if len(p) > 0 {
-		_p0 = unsafe.Pointer(&p[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	r0, _, e1 := Syscall(SYS_READ, uintptr(fd), uintptr(_p0), uintptr(len(p)))
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Removexattr(path string, attr string) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	var _p1 *byte
-	_p1, err = BytePtrFromString(attr)
-	if err != nil {
-		return
-	}
-	_, _, e1 := Syscall(SYS_REMOVEXATTR, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(_p1)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Setdomainname(p []byte) (err error) {
-	var _p0 unsafe.Pointer
-	if len(p) > 0 {
-		_p0 = unsafe.Pointer(&p[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	_, _, e1 := Syscall(SYS_SETDOMAINNAME, uintptr(_p0), uintptr(len(p)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Sethostname(p []byte) (err error) {
-	var _p0 unsafe.Pointer
-	if len(p) > 0 {
-		_p0 = unsafe.Pointer(&p[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	_, _, e1 := Syscall(SYS_SETHOSTNAME, uintptr(_p0), uintptr(len(p)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Setpgid(pid int, pgid int) (err error) {
-	_, _, e1 := RawSyscall(SYS_SETPGID, uintptr(pid), uintptr(pgid), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Setsid() (pid int, err error) {
-	r0, _, e1 := RawSyscall(SYS_SETSID, 0, 0, 0)
-	pid = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Settimeofday(tv *Timeval) (err error) {
-	_, _, e1 := RawSyscall(SYS_SETTIMEOFDAY, uintptr(unsafe.Pointer(tv)), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Setpriority(which int, who int, prio int) (err error) {
-	_, _, e1 := Syscall(SYS_SETPRIORITY, uintptr(which), uintptr(who), uintptr(prio))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Setxattr(path string, attr string, data []byte, flags int) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	var _p1 *byte
-	_p1, err = BytePtrFromString(attr)
-	if err != nil {
-		return
-	}
-	var _p2 unsafe.Pointer
-	if len(data) > 0 {
-		_p2 = unsafe.Pointer(&data[0])
-	} else {
-		_p2 = unsafe.Pointer(&_zero)
-	}
-	_, _, e1 := Syscall6(SYS_SETXATTR, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(_p1)), uintptr(_p2), uintptr(len(data)), uintptr(flags), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Sync() {
-	Syscall(SYS_SYNC, 0, 0, 0)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Sysinfo(info *Sysinfo_t) (err error) {
-	_, _, e1 := RawSyscall(SYS_SYSINFO, uintptr(unsafe.Pointer(info)), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Tee(rfd int, wfd int, len int, flags int) (n int64, err error) {
-	r0, _, e1 := Syscall6(SYS_TEE, uintptr(rfd), uintptr(wfd), uintptr(len), uintptr(flags), 0, 0)
-	n = int64(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Tgkill(tgid int, tid int, sig Signal) (err error) {
-	_, _, e1 := RawSyscall(SYS_TGKILL, uintptr(tgid), uintptr(tid), uintptr(sig))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Times(tms *Tms) (ticks uintptr, err error) {
-	r0, _, e1 := RawSyscall(SYS_TIMES, uintptr(unsafe.Pointer(tms)), 0, 0)
-	ticks = uintptr(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Umask(mask int) (oldmask int) {
-	r0, _ := rawSyscallNoError(SYS_UMASK, uintptr(mask), 0, 0)
-	oldmask = int(r0)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Uname(buf *Utsname) (err error) {
-	_, _, e1 := RawSyscall(SYS_UNAME, uintptr(unsafe.Pointer(buf)), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Unmount(target string, flags int) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(target)
-	if err != nil {
-		return
-	}
-	_, _, e1 := Syscall(SYS_UMOUNT2, uintptr(unsafe.Pointer(_p0)), uintptr(flags), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Unshare(flags int) (err error) {
-	_, _, e1 := Syscall(SYS_UNSHARE, uintptr(flags), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func write(fd int, p []byte) (n int, err error) {
-	var _p0 unsafe.Pointer
-	if len(p) > 0 {
-		_p0 = unsafe.Pointer(&p[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	r0, _, e1 := Syscall(SYS_WRITE, uintptr(fd), uintptr(_p0), uintptr(len(p)))
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func exitThread(code int) (err error) {
-	_, _, e1 := Syscall(SYS_EXIT, uintptr(code), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func readlen(fd int, p *byte, np int) (n int, err error) {
-	r0, _, e1 := Syscall(SYS_READ, uintptr(fd), uintptr(unsafe.Pointer(p)), uintptr(np))
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func writelen(fd int, p *byte, np int) (n int, err error) {
-	r0, _, e1 := Syscall(SYS_WRITE, uintptr(fd), uintptr(unsafe.Pointer(p)), uintptr(np))
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func munmap(addr uintptr, length uintptr) (err error) {
-	_, _, e1 := Syscall(SYS_MUNMAP, uintptr(addr), uintptr(length), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Madvise(b []byte, advice int) (err error) {
-	var _p0 unsafe.Pointer
-	if len(b) > 0 {
-		_p0 = unsafe.Pointer(&b[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	_, _, e1 := Syscall(SYS_MADVISE, uintptr(_p0), uintptr(len(b)), uintptr(advice))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Mprotect(b []byte, prot int) (err error) {
-	var _p0 unsafe.Pointer
-	if len(b) > 0 {
-		_p0 = unsafe.Pointer(&b[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	_, _, e1 := Syscall(SYS_MPROTECT, uintptr(_p0), uintptr(len(b)), uintptr(prot))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Mlock(b []byte) (err error) {
-	var _p0 unsafe.Pointer
-	if len(b) > 0 {
-		_p0 = unsafe.Pointer(&b[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	_, _, e1 := Syscall(SYS_MLOCK, uintptr(_p0), uintptr(len(b)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Munlock(b []byte) (err error) {
-	var _p0 unsafe.Pointer
-	if len(b) > 0 {
-		_p0 = unsafe.Pointer(&b[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	_, _, e1 := Syscall(SYS_MUNLOCK, uintptr(_p0), uintptr(len(b)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Mlockall(flags int) (err error) {
-	_, _, e1 := Syscall(SYS_MLOCKALL, uintptr(flags), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Munlockall() (err error) {
-	_, _, e1 := Syscall(SYS_MUNLOCKALL, 0, 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Dup2(oldfd int, newfd int) (err error) {
-	_, _, e1 := Syscall(SYS_DUP2, uintptr(oldfd), uintptr(newfd), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func EpollCreate(size int) (fd int, err error) {
-	r0, _, e1 := RawSyscall(SYS_EPOLL_CREATE, uintptr(size), 0, 0)
-	fd = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Fchown(fd int, uid int, gid int) (err error) {
-	_, _, e1 := Syscall(SYS_FCHOWN, uintptr(fd), uintptr(uid), uintptr(gid))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Fstat(fd int, stat *Stat_t) (err error) {
-	_, _, e1 := Syscall(SYS_FSTAT, uintptr(fd), uintptr(unsafe.Pointer(stat)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Fstatfs(fd int, buf *Statfs_t) (err error) {
-	_, _, e1 := Syscall(SYS_FSTATFS, uintptr(fd), uintptr(unsafe.Pointer(buf)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Ftruncate(fd int, length int64) (err error) {
-	_, _, e1 := Syscall(SYS_FTRUNCATE, uintptr(fd), uintptr(length), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Getegid() (egid int) {
-	r0, _ := rawSyscallNoError(SYS_GETEGID, 0, 0, 0)
-	egid = int(r0)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Geteuid() (euid int) {
-	r0, _ := rawSyscallNoError(SYS_GETEUID, 0, 0, 0)
-	euid = int(r0)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Getgid() (gid int) {
-	r0, _ := rawSyscallNoError(SYS_GETGID, 0, 0, 0)
-	gid = int(r0)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Getrlimit(resource int, rlim *Rlimit) (err error) {
-	_, _, e1 := RawSyscall(SYS_GETRLIMIT, uintptr(resource), uintptr(unsafe.Pointer(rlim)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Getuid() (uid int) {
-	r0, _ := rawSyscallNoError(SYS_GETUID, 0, 0, 0)
-	uid = int(r0)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func InotifyInit() (fd int, err error) {
-	r0, _, e1 := RawSyscall(SYS_INOTIFY_INIT, 0, 0, 0)
-	fd = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Ioperm(from int, num int, on int) (err error) {
-	_, _, e1 := Syscall(SYS_IOPERM, uintptr(from), uintptr(num), uintptr(on))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Iopl(level int) (err error) {
-	_, _, e1 := Syscall(SYS_IOPL, uintptr(level), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Listen(s int, n int) (err error) {
-	_, _, e1 := Syscall(SYS_LISTEN, uintptr(s), uintptr(n), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Pause() (err error) {
-	_, _, e1 := Syscall(SYS_PAUSE, 0, 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Pread(fd int, p []byte, offset int64) (n int, err error) {
-	var _p0 unsafe.Pointer
-	if len(p) > 0 {
-		_p0 = unsafe.Pointer(&p[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	r0, _, e1 := Syscall6(SYS_PREAD64, uintptr(fd), uintptr(_p0), uintptr(len(p)), uintptr(offset), 0, 0)
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Pwrite(fd int, p []byte, offset int64) (n int, err error) {
-	var _p0 unsafe.Pointer
-	if len(p) > 0 {
-		_p0 = unsafe.Pointer(&p[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	r0, _, e1 := Syscall6(SYS_PWRITE64, uintptr(fd), uintptr(_p0), uintptr(len(p)), uintptr(offset), 0, 0)
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Renameat(olddirfd int, oldpath string, newdirfd int, newpath string) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(oldpath)
-	if err != nil {
-		return
-	}
-	var _p1 *byte
-	_p1, err = BytePtrFromString(newpath)
-	if err != nil {
-		return
-	}
-	_, _, e1 := Syscall6(SYS_RENAMEAT, uintptr(olddirfd), uintptr(unsafe.Pointer(_p0)), uintptr(newdirfd), uintptr(unsafe.Pointer(_p1)), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Seek(fd int, offset int64, whence int) (off int64, err error) {
-	r0, _, e1 := Syscall(SYS_LSEEK, uintptr(fd), uintptr(offset), uintptr(whence))
-	off = int64(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Select(nfd int, r *FdSet, w *FdSet, e *FdSet, timeout *Timeval) (n int, err error) {
-	r0, _, e1 := Syscall6(SYS_SELECT, uintptr(nfd), uintptr(unsafe.Pointer(r)), uintptr(unsafe.Pointer(w)), uintptr(unsafe.Pointer(e)), uintptr(unsafe.Pointer(timeout)), 0)
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func sendfile(outfd int, infd int, offset *int64, count int) (written int, err error) {
-	r0, _, e1 := Syscall6(SYS_SENDFILE, uintptr(outfd), uintptr(infd), uintptr(unsafe.Pointer(offset)), uintptr(count), 0, 0)
-	written = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Setfsgid(gid int) (err error) {
-	_, _, e1 := Syscall(SYS_SETFSGID, uintptr(gid), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Setfsuid(uid int) (err error) {
-	_, _, e1 := Syscall(SYS_SETFSUID, uintptr(uid), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Setrlimit(resource int, rlim *Rlimit) (err error) {
-	_, _, e1 := RawSyscall(SYS_SETRLIMIT, uintptr(resource), uintptr(unsafe.Pointer(rlim)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Shutdown(fd int, how int) (err error) {
-	_, _, e1 := Syscall(SYS_SHUTDOWN, uintptr(fd), uintptr(how), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Splice(rfd int, roff *int64, wfd int, woff *int64, len int, flags int) (n int64, err error) {
-	r0, _, e1 := Syscall6(SYS_SPLICE, uintptr(rfd), uintptr(unsafe.Pointer(roff)), uintptr(wfd), uintptr(unsafe.Pointer(woff)), uintptr(len), uintptr(flags))
-	n = int64(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Statfs(path string, buf *Statfs_t) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := Syscall(SYS_STATFS, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(buf)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func SyncFileRange(fd int, off int64, n int64, flags int) (err error) {
-	_, _, e1 := Syscall6(SYS_SYNC_FILE_RANGE, uintptr(fd), uintptr(off), uintptr(n), uintptr(flags), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Truncate(path string, length int64) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := Syscall(SYS_TRUNCATE, uintptr(unsafe.Pointer(_p0)), uintptr(length), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Ustat(dev int, ubuf *Ustat_t) (err error) {
-	_, _, e1 := Syscall(SYS_USTAT, uintptr(dev), uintptr(unsafe.Pointer(ubuf)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func accept(s int, rsa *RawSockaddrAny, addrlen *_Socklen) (fd int, err error) {
-	r0, _, e1 := Syscall(SYS_ACCEPT, uintptr(s), uintptr(unsafe.Pointer(rsa)), uintptr(unsafe.Pointer(addrlen)))
-	fd = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func accept4(s int, rsa *RawSockaddrAny, addrlen *_Socklen, flags int) (fd int, err error) {
-	r0, _, e1 := Syscall6(SYS_ACCEPT4, uintptr(s), uintptr(unsafe.Pointer(rsa)), uintptr(unsafe.Pointer(addrlen)), uintptr(flags), 0, 0)
-	fd = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func bind(s int, addr unsafe.Pointer, addrlen _Socklen) (err error) {
-	_, _, e1 := Syscall(SYS_BIND, uintptr(s), uintptr(addr), uintptr(addrlen))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func connect(s int, addr unsafe.Pointer, addrlen _Socklen) (err error) {
-	_, _, e1 := Syscall(SYS_CONNECT, uintptr(s), uintptr(addr), uintptr(addrlen))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func fstatat(fd int, path string, stat *Stat_t, flags int) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := Syscall6(SYS_NEWFSTATAT, uintptr(fd), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(stat)), uintptr(flags), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func getgroups(n int, list *_Gid_t) (nn int, err error) {
-	r0, _, e1 := RawSyscall(SYS_GETGROUPS, uintptr(n), uintptr(unsafe.Pointer(list)), 0)
-	nn = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func getsockopt(s int, level int, name int, val unsafe.Pointer, vallen *_Socklen) (err error) {
-	_, _, e1 := Syscall6(SYS_GETSOCKOPT, uintptr(s), uintptr(level), uintptr(name), uintptr(val), uintptr(unsafe.Pointer(vallen)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func setsockopt(s int, level int, name int, val unsafe.Pointer, vallen uintptr) (err error) {
-	_, _, e1 := Syscall6(SYS_SETSOCKOPT, uintptr(s), uintptr(level), uintptr(name), uintptr(val), uintptr(vallen), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func socket(domain int, typ int, proto int) (fd int, err error) {
-	r0, _, e1 := RawSyscall(SYS_SOCKET, uintptr(domain), uintptr(typ), uintptr(proto))
-	fd = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func socketpair(domain int, typ int, proto int, fd *[2]int32) (err error) {
-	_, _, e1 := RawSyscall6(SYS_SOCKETPAIR, uintptr(domain), uintptr(typ), uintptr(proto), uintptr(unsafe.Pointer(fd)), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func getpeername(fd int, rsa *RawSockaddrAny, addrlen *_Socklen) (err error) {
-	_, _, e1 := RawSyscall(SYS_GETPEERNAME, uintptr(fd), uintptr(unsafe.Pointer(rsa)), uintptr(unsafe.Pointer(addrlen)))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func getsockname(fd int, rsa *RawSockaddrAny, addrlen *_Socklen) (err error) {
-	_, _, e1 := RawSyscall(SYS_GETSOCKNAME, uintptr(fd), uintptr(unsafe.Pointer(rsa)), uintptr(unsafe.Pointer(addrlen)))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func recvfrom(fd int, p []byte, flags int, from *RawSockaddrAny, fromlen *_Socklen) (n int, err error) {
-	var _p0 unsafe.Pointer
-	if len(p) > 0 {
-		_p0 = unsafe.Pointer(&p[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	r0, _, e1 := Syscall6(SYS_RECVFROM, uintptr(fd), uintptr(_p0), uintptr(len(p)), uintptr(flags), uintptr(unsafe.Pointer(from)), uintptr(unsafe.Pointer(fromlen)))
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func sendto(s int, buf []byte, flags int, to unsafe.Pointer, addrlen _Socklen) (err error) {
-	var _p0 unsafe.Pointer
-	if len(buf) > 0 {
-		_p0 = unsafe.Pointer(&buf[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	_, _, e1 := Syscall6(SYS_SENDTO, uintptr(s), uintptr(_p0), uintptr(len(buf)), uintptr(flags), uintptr(to), uintptr(addrlen))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func recvmsg(s int, msg *Msghdr, flags int) (n int, err error) {
-	r0, _, e1 := Syscall(SYS_RECVMSG, uintptr(s), uintptr(unsafe.Pointer(msg)), uintptr(flags))
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func sendmsg(s int, msg *Msghdr, flags int) (n int, err error) {
-	r0, _, e1 := Syscall(SYS_SENDMSG, uintptr(s), uintptr(unsafe.Pointer(msg)), uintptr(flags))
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func mmap(addr uintptr, length uintptr, prot int, flags int, fd int, offset int64) (xaddr uintptr, err error) {
-	r0, _, e1 := Syscall6(SYS_MMAP, uintptr(addr), uintptr(length), uintptr(prot), uintptr(flags), uintptr(fd), uintptr(offset))
-	xaddr = uintptr(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) {
-	var _p0 unsafe.Pointer
-	if len(events) > 0 {
-		_p0 = unsafe.Pointer(&events[0])
-	} else {
-		_p0 = unsafe.Pointer(&_zero)
-	}
-	r0, _, e1 := Syscall6(SYS_EPOLL_WAIT, uintptr(epfd), uintptr(_p0), uintptr(len(events)), uintptr(msec), 0, 0)
-	n = int(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func futimesat(dirfd int, path string, times *[2]Timeval) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := Syscall(SYS_FUTIMESAT, uintptr(dirfd), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(times)))
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func Utime(path string, buf *Utimbuf) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := Syscall(SYS_UTIME, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(buf)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func utimes(path string, times *[2]Timeval) (err error) {
-	var _p0 *byte
-	_p0, err = BytePtrFromString(path)
-	if err != nil {
-		return
-	}
-	_, _, e1 := Syscall(SYS_UTIMES, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(times)), 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
diff --git a/contrib/go/_std_1.18/src/text/template/doc.go b/contrib/go/_std_1.18/src/text/template/doc.go
deleted file mode 100644
index 10093881fb..0000000000
--- a/contrib/go/_std_1.18/src/text/template/doc.go
+++ /dev/null
@@ -1,465 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-/*
-Package template implements data-driven templates for generating textual output.
-
-To generate HTML output, see package html/template, which has the same interface
-as this package but automatically secures HTML output against certain attacks.
-
-Templates are executed by applying them to a data structure. Annotations in the
-template refer to elements of the data structure (typically a field of a struct
-or a key in a map) to control execution and derive values to be displayed.
-Execution of the template walks the structure and sets the cursor, represented
-by a period '.' and called "dot", to the value at the current location in the
-structure as execution proceeds.
-
-The input text for a template is UTF-8-encoded text in any format.
-"Actions"--data evaluations or control structures--are delimited by
-"{{" and "}}"; all text outside actions is copied to the output unchanged.
-Except for raw strings, actions may not span newlines, although comments can.
-
-Once parsed, a template may be executed safely in parallel, although if parallel
-executions share a Writer the output may be interleaved.
-
-Here is a trivial example that prints "17 items are made of wool".
-
-	type Inventory struct {
-		Material string
-		Count    uint
-	}
-	sweaters := Inventory{"wool", 17}
-	tmpl, err := template.New("test").Parse("{{.Count}} items are made of {{.Material}}")
-	if err != nil { panic(err) }
-	err = tmpl.Execute(os.Stdout, sweaters)
-	if err != nil { panic(err) }
-
-More intricate examples appear below.
-
-Text and spaces
-
-By default, all text between actions is copied verbatim when the template is
-executed. For example, the string " items are made of " in the example above
-appears on standard output when the program is run.
-
-However, to aid in formatting template source code, if an action's left
-delimiter (by default "{{") is followed immediately by a minus sign and white
-space, all trailing white space is trimmed from the immediately preceding text.
-Similarly, if the right delimiter ("}}") is preceded by white space and a minus
-sign, all leading white space is trimmed from the immediately following text.
-In these trim markers, the white space must be present:
-"{{- 3}}" is like "{{3}}" but trims the immediately preceding text, while
-"{{-3}}" parses as an action containing the number -3.
-
-For instance, when executing the template whose source is
-
-	"{{23 -}} < {{- 45}}"
-
-the generated output would be
-
-	"23<45"
-
-For this trimming, the definition of white space characters is the same as in Go:
-space, horizontal tab, carriage return, and newline.
-
-Actions
-
-Here is the list of actions. "Arguments" and "pipelines" are evaluations of
-data, defined in detail in the corresponding sections that follow.
-
-*/
-//	{{/* a comment */}}
-//	{{- /* a comment with white space trimmed from preceding and following text */ -}}
-//		A comment; discarded. May contain newlines.
-//		Comments do not nest and must start and end at the
-//		delimiters, as shown here.
-/*
-
-	{{pipeline}}
-		The default textual representation (the same as would be
-		printed by fmt.Print) of the value of the pipeline is copied
-		to the output.
-
-	{{if pipeline}} T1 {{end}}
-		If the value of the pipeline is empty, no output is generated;
-		otherwise, T1 is executed. The empty values are false, 0, any
-		nil pointer or interface value, and any array, slice, map, or
-		string of length zero.
-		Dot is unaffected.
-
-	{{if pipeline}} T1 {{else}} T0 {{end}}
-		If the value of the pipeline is empty, T0 is executed;
-		otherwise, T1 is executed. Dot is unaffected.
-
-	{{if pipeline}} T1 {{else if pipeline}} T0 {{end}}
-		To simplify the appearance of if-else chains, the else action
-		of an if may include another if directly; the effect is exactly
-		the same as writing
-			{{if pipeline}} T1 {{else}}{{if pipeline}} T0 {{end}}{{end}}
-
-	{{range pipeline}} T1 {{end}}
-		The value of the pipeline must be an array, slice, map, or channel.
-		If the value of the pipeline has length zero, nothing is output;
-		otherwise, dot is set to the successive elements of the array,
-		slice, or map and T1 is executed. If the value is a map and the
-		keys are of basic type with a defined order, the elements will be
-		visited in sorted key order.
-
-	{{range pipeline}} T1 {{else}} T0 {{end}}
-		The value of the pipeline must be an array, slice, map, or channel.
-		If the value of the pipeline has length zero, dot is unaffected and
-		T0 is executed; otherwise, dot is set to the successive elements
-		of the array, slice, or map and T1 is executed.
-
-	{{break}}
-		The innermost {{range pipeline}} loop is ended early, stopping the
-		current iteration and bypassing all remaining iterations.
-
-	{{continue}}
-		The current iteration of the innermost {{range pipeline}} loop is
-		stopped, and the loop starts the next iteration.
-
-	{{template "name"}}
-		The template with the specified name is executed with nil data.
-
-	{{template "name" pipeline}}
-		The template with the specified name is executed with dot set
-		to the value of the pipeline.
-
-	{{block "name" pipeline}} T1 {{end}}
-		A block is shorthand for defining a template
-			{{define "name"}} T1 {{end}}
-		and then executing it in place
-			{{template "name" pipeline}}
-		The typical use is to define a set of root templates that are
-		then customized by redefining the block templates within.
-
-	{{with pipeline}} T1 {{end}}
-		If the value of the pipeline is empty, no output is generated;
-		otherwise, dot is set to the value of the pipeline and T1 is
-		executed.
-
-	{{with pipeline}} T1 {{else}} T0 {{end}}
-		If the value of the pipeline is empty, dot is unaffected and T0
-		is executed; otherwise, dot is set to the value of the pipeline
-		and T1 is executed.
-
-Arguments
-
-An argument is a simple value, denoted by one of the following.
-
-	- A boolean, string, character, integer, floating-point, imaginary
-	  or complex constant in Go syntax. These behave like Go's untyped
-	  constants. Note that, as in Go, whether a large integer constant
-	  overflows when assigned or passed to a function can depend on whether
-	  the host machine's ints are 32 or 64 bits.
-	- The keyword nil, representing an untyped Go nil.
-	- The character '.' (period):
-		.
-	  The result is the value of dot.
-	- A variable name, which is a (possibly empty) alphanumeric string
-	  preceded by a dollar sign, such as
-		$piOver2
-	  or
-		$
-	  The result is the value of the variable.
-	  Variables are described below.
-	- The name of a field of the data, which must be a struct, preceded
-	  by a period, such as
-		.Field
-	  The result is the value of the field. Field invocations may be
-	  chained:
-	    .Field1.Field2
-	  Fields can also be evaluated on variables, including chaining:
-	    $x.Field1.Field2
-	- The name of a key of the data, which must be a map, preceded
-	  by a period, such as
-		.Key
-	  The result is the map element value indexed by the key.
-	  Key invocations may be chained and combined with fields to any
-	  depth:
-	    .Field1.Key1.Field2.Key2
-	  Although the key must be an alphanumeric identifier, unlike with
-	  field names they do not need to start with an upper case letter.
-	  Keys can also be evaluated on variables, including chaining:
-	    $x.key1.key2
-	- The name of a niladic method of the data, preceded by a period,
-	  such as
-		.Method
-	  The result is the value of invoking the method with dot as the
-	  receiver, dot.Method(). Such a method must have one return value (of
-	  any type) or two return values, the second of which is an error.
-	  If it has two and the returned error is non-nil, execution terminates
-	  and an error is returned to the caller as the value of Execute.
-	  Method invocations may be chained and combined with fields and keys
-	  to any depth:
-	    .Field1.Key1.Method1.Field2.Key2.Method2
-	  Methods can also be evaluated on variables, including chaining:
-	    $x.Method1.Field
-	- The name of a niladic function, such as
-		fun
-	  The result is the value of invoking the function, fun(). The return
-	  types and values behave as in methods. Functions and function
-	  names are described below.
-	- A parenthesized instance of one the above, for grouping. The result
-	  may be accessed by a field or map key invocation.
-		print (.F1 arg1) (.F2 arg2)
-		(.StructValuedMethod "arg").Field
-
-Arguments may evaluate to any type; if they are pointers the implementation
-automatically indirects to the base type when required.
-If an evaluation yields a function value, such as a function-valued
-field of a struct, the function is not invoked automatically, but it
-can be used as a truth value for an if action and the like. To invoke
-it, use the call function, defined below.
-
-Pipelines
-
-A pipeline is a possibly chained sequence of "commands". A command is a simple
-value (argument) or a function or method call, possibly with multiple arguments:
-
-	Argument
-		The result is the value of evaluating the argument.
-	.Method [Argument...]
-		The method can be alone or the last element of a chain but,
-		unlike methods in the middle of a chain, it can take arguments.
-		The result is the value of calling the method with the
-		arguments:
-			dot.Method(Argument1, etc.)
-	functionName [Argument...]
-		The result is the value of calling the function associated
-		with the name:
-			function(Argument1, etc.)
-		Functions and function names are described below.
-
-A pipeline may be "chained" by separating a sequence of commands with pipeline
-characters '|'. In a chained pipeline, the result of each command is
-passed as the last argument of the following command. The output of the final
-command in the pipeline is the value of the pipeline.
-
-The output of a command will be either one value or two values, the second of
-which has type error. If that second value is present and evaluates to
-non-nil, execution terminates and the error is returned to the caller of
-Execute.
-
-Variables
-
-A pipeline inside an action may initialize a variable to capture the result.
-The initialization has syntax
-
-	$variable := pipeline
-
-where $variable is the name of the variable. An action that declares a
-variable produces no output.
-
-Variables previously declared can also be assigned, using the syntax
-
-	$variable = pipeline
-
-If a "range" action initializes a variable, the variable is set to the
-successive elements of the iteration. Also, a "range" may declare two
-variables, separated by a comma:
-
-	range $index, $element := pipeline
-
-in which case $index and $element are set to the successive values of the
-array/slice index or map key and element, respectively. Note that if there is
-only one variable, it is assigned the element; this is opposite to the
-convention in Go range clauses.
-
-A variable's scope extends to the "end" action of the control structure ("if",
-"with", or "range") in which it is declared, or to the end of the template if
-there is no such control structure. A template invocation does not inherit
-variables from the point of its invocation.
-
-When execution begins, $ is set to the data argument passed to Execute, that is,
-to the starting value of dot.
-
-Examples
-
-Here are some example one-line templates demonstrating pipelines and variables.
-All produce the quoted word "output":
-
-	{{"\"output\""}}
-		A string constant.
-	{{`"output"`}}
-		A raw string constant.
-	{{printf "%q" "output"}}
-		A function call.
-	{{"output" | printf "%q"}}
-		A function call whose final argument comes from the previous
-		command.
-	{{printf "%q" (print "out" "put")}}
-		A parenthesized argument.
-	{{"put" | printf "%s%s" "out" | printf "%q"}}
-		A more elaborate call.
-	{{"output" | printf "%s" | printf "%q"}}
-		A longer chain.
-	{{with "output"}}{{printf "%q" .}}{{end}}
-		A with action using dot.
-	{{with $x := "output" | printf "%q"}}{{$x}}{{end}}
-		A with action that creates and uses a variable.
-	{{with $x := "output"}}{{printf "%q" $x}}{{end}}
-		A with action that uses the variable in another action.
-	{{with $x := "output"}}{{$x | printf "%q"}}{{end}}
-		The same, but pipelined.
-
-Functions
-
-During execution functions are found in two function maps: first in the
-template, then in the global function map. By default, no functions are defined
-in the template but the Funcs method can be used to add them.
-
-Predefined global functions are named as follows.
-
-	and
-		Returns the boolean AND of its arguments by returning the
-		first empty argument or the last argument. That is,
-		"and x y" behaves as "if x then y else x."
-		Evaluation proceeds through the arguments left to right
-		and returns when the result is determined.
-	call
-		Returns the result of calling the first argument, which
-		must be a function, with the remaining arguments as parameters.
-		Thus "call .X.Y 1 2" is, in Go notation, dot.X.Y(1, 2) where
-		Y is a func-valued field, map entry, or the like.
-		The first argument must be the result of an evaluation
-		that yields a value of function type (as distinct from
-		a predefined function such as print). The function must
-		return either one or two result values, the second of which
-		is of type error. If the arguments don't match the function
-		or the returned error value is non-nil, execution stops.
-	html
-		Returns the escaped HTML equivalent of the textual
-		representation of its arguments. This function is unavailable
-		in html/template, with a few exceptions.
-	index
-		Returns the result of indexing its first argument by the
-		following arguments. Thus "index x 1 2 3" is, in Go syntax,
-		x[1][2][3]. Each indexed item must be a map, slice, or array.
-	slice
-		slice returns the result of slicing its first argument by the
-		remaining arguments. Thus "slice x 1 2" is, in Go syntax, x[1:2],
-		while "slice x" is x[:], "slice x 1" is x[1:], and "slice x 1 2 3"
-		is x[1:2:3]. The first argument must be a string, slice, or array.
-	js
-		Returns the escaped JavaScript equivalent of the textual
-		representation of its arguments.
-	len
-		Returns the integer length of its argument.
-	not
-		Returns the boolean negation of its single argument.
-	or
-		Returns the boolean OR of its arguments by returning the
-		first non-empty argument or the last argument, that is,
-		"or x y" behaves as "if x then x else y".
-		Evaluation proceeds through the arguments left to right
-		and returns when the result is determined.
-	print
-		An alias for fmt.Sprint
-	printf
-		An alias for fmt.Sprintf
-	println
-		An alias for fmt.Sprintln
-	urlquery
-		Returns the escaped value of the textual representation of
-		its arguments in a form suitable for embedding in a URL query.
-		This function is unavailable in html/template, with a few
-		exceptions.
-
-The boolean functions take any zero value to be false and a non-zero
-value to be true.
-
-There is also a set of binary comparison operators defined as
-functions:
-
-	eq
-		Returns the boolean truth of arg1 == arg2
-	ne
-		Returns the boolean truth of arg1 != arg2
-	lt
-		Returns the boolean truth of arg1 < arg2
-	le
-		Returns the boolean truth of arg1 <= arg2
-	gt
-		Returns the boolean truth of arg1 > arg2
-	ge
-		Returns the boolean truth of arg1 >= arg2
-
-For simpler multi-way equality tests, eq (only) accepts two or more
-arguments and compares the second and subsequent to the first,
-returning in effect
-
-	arg1==arg2 || arg1==arg3 || arg1==arg4 ...
-
-(Unlike with || in Go, however, eq is a function call and all the
-arguments will be evaluated.)
-
-The comparison functions work on any values whose type Go defines as
-comparable. For basic types such as integers, the rules are relaxed:
-size and exact type are ignored, so any integer value, signed or unsigned,
-may be compared with any other integer value. (The arithmetic value is compared,
-not the bit pattern, so all negative integers are less than all unsigned integers.)
-However, as usual, one may not compare an int with a float32 and so on.
-
-Associated templates
-
-Each template is named by a string specified when it is created. Also, each
-template is associated with zero or more other templates that it may invoke by
-name; such associations are transitive and form a name space of templates.
-
-A template may use a template invocation to instantiate another associated
-template; see the explanation of the "template" action above. The name must be
-that of a template associated with the template that contains the invocation.
-
-Nested template definitions
-
-When parsing a template, another template may be defined and associated with the
-template being parsed. Template definitions must appear at the top level of the
-template, much like global variables in a Go program.
-
-The syntax of such definitions is to surround each template declaration with a
-"define" and "end" action.
-
-The define action names the template being created by providing a string
-constant. Here is a simple example:
-
-	`{{define "T1"}}ONE{{end}}
-	{{define "T2"}}TWO{{end}}
-	{{define "T3"}}{{template "T1"}} {{template "T2"}}{{end}}
-	{{template "T3"}}`
-
-This defines two templates, T1 and T2, and a third T3 that invokes the other two
-when it is executed. Finally it invokes T3. If executed this template will
-produce the text
-
-	ONE TWO
-
-By construction, a template may reside in only one association. If it's
-necessary to have a template addressable from multiple associations, the
-template definition must be parsed multiple times to create distinct *Template
-values, or must be copied with the Clone or AddParseTree method.
-
-Parse may be called multiple times to assemble the various associated templates;
-see the ParseFiles and ParseGlob functions and methods for simple ways to parse
-related templates stored in files.
-
-A template may be executed directly or through ExecuteTemplate, which executes
-an associated template identified by name. To invoke our example above, we
-might write,
-
-	err := tmpl.Execute(os.Stdout, "no data needed")
-	if err != nil {
-		log.Fatalf("execution failed: %s", err)
-	}
-
-or to invoke a particular template explicitly by name,
-
-	err := tmpl.ExecuteTemplate(os.Stdout, "T2", "no data needed")
-	if err != nil {
-		log.Fatalf("execution failed: %s", err)
-	}
-
-*/
-package template
diff --git a/contrib/go/_std_1.18/src/text/template/funcs.go b/contrib/go/_std_1.18/src/text/template/funcs.go
deleted file mode 100644
index dca5ed28db..0000000000
--- a/contrib/go/_std_1.18/src/text/template/funcs.go
+++ /dev/null
@@ -1,753 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package template
-
-import (
-	"bytes"
-	"errors"
-	"fmt"
-	"io"
-	"net/url"
-	"reflect"
-	"strings"
-	"sync"
-	"unicode"
-	"unicode/utf8"
-)
-
-// FuncMap is the type of the map defining the mapping from names to functions.
-// Each function must have either a single return value, or two return values of
-// which the second has type error. In that case, if the second (error)
-// return value evaluates to non-nil during execution, execution terminates and
-// Execute returns that error.
-//
-// Errors returned by Execute wrap the underlying error; call errors.As to
-// uncover them.
-//
-// When template execution invokes a function with an argument list, that list
-// must be assignable to the function's parameter types. Functions meant to
-// apply to arguments of arbitrary type can use parameters of type interface{} or
-// of type reflect.Value. Similarly, functions meant to return a result of arbitrary
-// type can return interface{} or reflect.Value.
-type FuncMap map[string]any
-
-// builtins returns the FuncMap.
-// It is not a global variable so the linker can dead code eliminate
-// more when this isn't called. See golang.org/issue/36021.
-// TODO: revert this back to a global map once golang.org/issue/2559 is fixed.
-func builtins() FuncMap {
-	return FuncMap{
-		"and":      and,
-		"call":     call,
-		"html":     HTMLEscaper,
-		"index":    index,
-		"slice":    slice,
-		"js":       JSEscaper,
-		"len":      length,
-		"not":      not,
-		"or":       or,
-		"print":    fmt.Sprint,
-		"printf":   fmt.Sprintf,
-		"println":  fmt.Sprintln,
-		"urlquery": URLQueryEscaper,
-
-		// Comparisons
-		"eq": eq, // ==
-		"ge": ge, // >=
-		"gt": gt, // >
-		"le": le, // <=
-		"lt": lt, // <
-		"ne": ne, // !=
-	}
-}
-
-var builtinFuncsOnce struct {
-	sync.Once
-	v map[string]reflect.Value
-}
-
-// builtinFuncsOnce lazily computes & caches the builtinFuncs map.
-// TODO: revert this back to a global map once golang.org/issue/2559 is fixed.
-func builtinFuncs() map[string]reflect.Value {
-	builtinFuncsOnce.Do(func() {
-		builtinFuncsOnce.v = createValueFuncs(builtins())
-	})
-	return builtinFuncsOnce.v
-}
-
-// createValueFuncs turns a FuncMap into a map[string]reflect.Value
-func createValueFuncs(funcMap FuncMap) map[string]reflect.Value {
-	m := make(map[string]reflect.Value)
-	addValueFuncs(m, funcMap)
-	return m
-}
-
-// addValueFuncs adds to values the functions in funcs, converting them to reflect.Values.
-func addValueFuncs(out map[string]reflect.Value, in FuncMap) {
-	for name, fn := range in {
-		if !goodName(name) {
-			panic(fmt.Errorf("function name %q is not a valid identifier", name))
-		}
-		v := reflect.ValueOf(fn)
-		if v.Kind() != reflect.Func {
-			panic("value for " + name + " not a function")
-		}
-		if !goodFunc(v.Type()) {
-			panic(fmt.Errorf("can't install method/function %q with %d results", name, v.Type().NumOut()))
-		}
-		out[name] = v
-	}
-}
-
-// addFuncs adds to values the functions in funcs. It does no checking of the input -
-// call addValueFuncs first.
-func addFuncs(out, in FuncMap) {
-	for name, fn := range in {
-		out[name] = fn
-	}
-}
-
-// goodFunc reports whether the function or method has the right result signature.
-func goodFunc(typ reflect.Type) bool {
-	// We allow functions with 1 result or 2 results where the second is an error.
-	switch {
-	case typ.NumOut() == 1:
-		return true
-	case typ.NumOut() == 2 && typ.Out(1) == errorType:
-		return true
-	}
-	return false
-}
-
-// goodName reports whether the function name is a valid identifier.
-func goodName(name string) bool {
-	if name == "" {
-		return false
-	}
-	for i, r := range name {
-		switch {
-		case r == '_':
-		case i == 0 && !unicode.IsLetter(r):
-			return false
-		case !unicode.IsLetter(r) && !unicode.IsDigit(r):
-			return false
-		}
-	}
-	return true
-}
-
-// findFunction looks for a function in the template, and global map.
-func findFunction(name string, tmpl *Template) (v reflect.Value, isBuiltin, ok bool) {
-	if tmpl != nil && tmpl.common != nil {
-		tmpl.muFuncs.RLock()
-		defer tmpl.muFuncs.RUnlock()
-		if fn := tmpl.execFuncs[name]; fn.IsValid() {
-			return fn, false, true
-		}
-	}
-	if fn := builtinFuncs()[name]; fn.IsValid() {
-		return fn, true, true
-	}
-	return reflect.Value{}, false, false
-}
-
-// prepareArg checks if value can be used as an argument of type argType, and
-// converts an invalid value to appropriate zero if possible.
-func prepareArg(value reflect.Value, argType reflect.Type) (reflect.Value, error) {
-	if !value.IsValid() {
-		if !canBeNil(argType) {
-			return reflect.Value{}, fmt.Errorf("value is nil; should be of type %s", argType)
-		}
-		value = reflect.Zero(argType)
-	}
-	if value.Type().AssignableTo(argType) {
-		return value, nil
-	}
-	if intLike(value.Kind()) && intLike(argType.Kind()) && value.Type().ConvertibleTo(argType) {
-		value = value.Convert(argType)
-		return value, nil
-	}
-	return reflect.Value{}, fmt.Errorf("value has type %s; should be %s", value.Type(), argType)
-}
-
-func intLike(typ reflect.Kind) bool {
-	switch typ {
-	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
-		return true
-	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
-		return true
-	}
-	return false
-}
-
-// indexArg checks if a reflect.Value can be used as an index, and converts it to int if possible.
-func indexArg(index reflect.Value, cap int) (int, error) {
-	var x int64
-	switch index.Kind() {
-	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
-		x = index.Int()
-	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
-		x = int64(index.Uint())
-	case reflect.Invalid:
-		return 0, fmt.Errorf("cannot index slice/array with nil")
-	default:
-		return 0, fmt.Errorf("cannot index slice/array with type %s", index.Type())
-	}
-	if x < 0 || int(x) < 0 || int(x) > cap {
-		return 0, fmt.Errorf("index out of range: %d", x)
-	}
-	return int(x), nil
-}
-
-// Indexing.
-
-// index returns the result of indexing its first argument by the following
-// arguments. Thus "index x 1 2 3" is, in Go syntax, x[1][2][3]. Each
-// indexed item must be a map, slice, or array.
-func index(item reflect.Value, indexes ...reflect.Value) (reflect.Value, error) {
-	item = indirectInterface(item)
-	if !item.IsValid() {
-		return reflect.Value{}, fmt.Errorf("index of untyped nil")
-	}
-	for _, index := range indexes {
-		index = indirectInterface(index)
-		var isNil bool
-		if item, isNil = indirect(item); isNil {
-			return reflect.Value{}, fmt.Errorf("index of nil pointer")
-		}
-		switch item.Kind() {
-		case reflect.Array, reflect.Slice, reflect.String:
-			x, err := indexArg(index, item.Len())
-			if err != nil {
-				return reflect.Value{}, err
-			}
-			item = item.Index(x)
-		case reflect.Map:
-			index, err := prepareArg(index, item.Type().Key())
-			if err != nil {
-				return reflect.Value{}, err
-			}
-			if x := item.MapIndex(index); x.IsValid() {
-				item = x
-			} else {
-				item = reflect.Zero(item.Type().Elem())
-			}
-		case reflect.Invalid:
-			// the loop holds invariant: item.IsValid()
-			panic("unreachable")
-		default:
-			return reflect.Value{}, fmt.Errorf("can't index item of type %s", item.Type())
-		}
-	}
-	return item, nil
-}
-
-// Slicing.
-
-// slice returns the result of slicing its first argument by the remaining
-// arguments. Thus "slice x 1 2" is, in Go syntax, x[1:2], while "slice x"
-// is x[:], "slice x 1" is x[1:], and "slice x 1 2 3" is x[1:2:3]. The first
-// argument must be a string, slice, or array.
-func slice(item reflect.Value, indexes ...reflect.Value) (reflect.Value, error) {
-	item = indirectInterface(item)
-	if !item.IsValid() {
-		return reflect.Value{}, fmt.Errorf("slice of untyped nil")
-	}
-	if len(indexes) > 3 {
-		return reflect.Value{}, fmt.Errorf("too many slice indexes: %d", len(indexes))
-	}
-	var cap int
-	switch item.Kind() {
-	case reflect.String:
-		if len(indexes) == 3 {
-			return reflect.Value{}, fmt.Errorf("cannot 3-index slice a string")
-		}
-		cap = item.Len()
-	case reflect.Array, reflect.Slice:
-		cap = item.Cap()
-	default:
-		return reflect.Value{}, fmt.Errorf("can't slice item of type %s", item.Type())
-	}
-	// set default values for cases item[:], item[i:].
-	idx := [3]int{0, item.Len()}
-	for i, index := range indexes {
-		x, err := indexArg(index, cap)
-		if err != nil {
-			return reflect.Value{}, err
-		}
-		idx[i] = x
-	}
-	// given item[i:j], make sure i <= j.
-	if idx[0] > idx[1] {
-		return reflect.Value{}, fmt.Errorf("invalid slice index: %d > %d", idx[0], idx[1])
-	}
-	if len(indexes) < 3 {
-		return item.Slice(idx[0], idx[1]), nil
-	}
-	// given item[i:j:k], make sure i <= j <= k.
-	if idx[1] > idx[2] {
-		return reflect.Value{}, fmt.Errorf("invalid slice index: %d > %d", idx[1], idx[2])
-	}
-	return item.Slice3(idx[0], idx[1], idx[2]), nil
-}
-
-// Length
-
-// length returns the length of the item, with an error if it has no defined length.
-func length(item reflect.Value) (int, error) {
-	item, isNil := indirect(item)
-	if isNil {
-		return 0, fmt.Errorf("len of nil pointer")
-	}
-	switch item.Kind() {
-	case reflect.Array, reflect.Chan, reflect.Map, reflect.Slice, reflect.String:
-		return item.Len(), nil
-	}
-	return 0, fmt.Errorf("len of type %s", item.Type())
-}
-
-// Function invocation
-
-// call returns the result of evaluating the first argument as a function.
-// The function must return 1 result, or 2 results, the second of which is an error.
-func call(fn reflect.Value, args ...reflect.Value) (reflect.Value, error) {
-	fn = indirectInterface(fn)
-	if !fn.IsValid() {
-		return reflect.Value{}, fmt.Errorf("call of nil")
-	}
-	typ := fn.Type()
-	if typ.Kind() != reflect.Func {
-		return reflect.Value{}, fmt.Errorf("non-function of type %s", typ)
-	}
-	if !goodFunc(typ) {
-		return reflect.Value{}, fmt.Errorf("function called with %d args; should be 1 or 2", typ.NumOut())
-	}
-	numIn := typ.NumIn()
-	var dddType reflect.Type
-	if typ.IsVariadic() {
-		if len(args) < numIn-1 {
-			return reflect.Value{}, fmt.Errorf("wrong number of args: got %d want at least %d", len(args), numIn-1)
-		}
-		dddType = typ.In(numIn - 1).Elem()
-	} else {
-		if len(args) != numIn {
-			return reflect.Value{}, fmt.Errorf("wrong number of args: got %d want %d", len(args), numIn)
-		}
-	}
-	argv := make([]reflect.Value, len(args))
-	for i, arg := range args {
-		arg = indirectInterface(arg)
-		// Compute the expected type. Clumsy because of variadics.
-		argType := dddType
-		if !typ.IsVariadic() || i < numIn-1 {
-			argType = typ.In(i)
-		}
-
-		var err error
-		if argv[i], err = prepareArg(arg, argType); err != nil {
-			return reflect.Value{}, fmt.Errorf("arg %d: %w", i, err)
-		}
-	}
-	return safeCall(fn, argv)
-}
-
-// safeCall runs fun.Call(args), and returns the resulting value and error, if
-// any. If the call panics, the panic value is returned as an error.
-func safeCall(fun reflect.Value, args []reflect.Value) (val reflect.Value, err error) {
-	defer func() {
-		if r := recover(); r != nil {
-			if e, ok := r.(error); ok {
-				err = e
-			} else {
-				err = fmt.Errorf("%v", r)
-			}
-		}
-	}()
-	ret := fun.Call(args)
-	if len(ret) == 2 && !ret[1].IsNil() {
-		return ret[0], ret[1].Interface().(error)
-	}
-	return ret[0], nil
-}
-
-// Boolean logic.
-
-func truth(arg reflect.Value) bool {
-	t, _ := isTrue(indirectInterface(arg))
-	return t
-}
-
-// and computes the Boolean AND of its arguments, returning
-// the first false argument it encounters, or the last argument.
-func and(arg0 reflect.Value, args ...reflect.Value) reflect.Value {
-	panic("unreachable") // implemented as a special case in evalCall
-}
-
-// or computes the Boolean OR of its arguments, returning
-// the first true argument it encounters, or the last argument.
-func or(arg0 reflect.Value, args ...reflect.Value) reflect.Value {
-	panic("unreachable") // implemented as a special case in evalCall
-}
-
-// not returns the Boolean negation of its argument.
-func not(arg reflect.Value) bool {
-	return !truth(arg)
-}
-
-// Comparison.
-
-// TODO: Perhaps allow comparison between signed and unsigned integers.
-
-var (
-	errBadComparisonType = errors.New("invalid type for comparison")
-	errBadComparison     = errors.New("incompatible types for comparison")
-	errNoComparison      = errors.New("missing argument for comparison")
-)
-
-type kind int
-
-const (
-	invalidKind kind = iota
-	boolKind
-	complexKind
-	intKind
-	floatKind
-	stringKind
-	uintKind
-)
-
-func basicKind(v reflect.Value) (kind, error) {
-	switch v.Kind() {
-	case reflect.Bool:
-		return boolKind, nil
-	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
-		return intKind, nil
-	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
-		return uintKind, nil
-	case reflect.Float32, reflect.Float64:
-		return floatKind, nil
-	case reflect.Complex64, reflect.Complex128:
-		return complexKind, nil
-	case reflect.String:
-		return stringKind, nil
-	}
-	return invalidKind, errBadComparisonType
-}
-
-// eq evaluates the comparison a == b || a == c || ...
-func eq(arg1 reflect.Value, arg2 ...reflect.Value) (bool, error) {
-	arg1 = indirectInterface(arg1)
-	if arg1 != zero {
-		if t1 := arg1.Type(); !t1.Comparable() {
-			return false, fmt.Errorf("uncomparable type %s: %v", t1, arg1)
-		}
-	}
-	if len(arg2) == 0 {
-		return false, errNoComparison
-	}
-	k1, _ := basicKind(arg1)
-	for _, arg := range arg2 {
-		arg = indirectInterface(arg)
-		k2, _ := basicKind(arg)
-		truth := false
-		if k1 != k2 {
-			// Special case: Can compare integer values regardless of type's sign.
-			switch {
-			case k1 == intKind && k2 == uintKind:
-				truth = arg1.Int() >= 0 && uint64(arg1.Int()) == arg.Uint()
-			case k1 == uintKind && k2 == intKind:
-				truth = arg.Int() >= 0 && arg1.Uint() == uint64(arg.Int())
-			default:
-				if arg1 != zero && arg != zero {
-					return false, errBadComparison
-				}
-			}
-		} else {
-			switch k1 {
-			case boolKind:
-				truth = arg1.Bool() == arg.Bool()
-			case complexKind:
-				truth = arg1.Complex() == arg.Complex()
-			case floatKind:
-				truth = arg1.Float() == arg.Float()
-			case intKind:
-				truth = arg1.Int() == arg.Int()
-			case stringKind:
-				truth = arg1.String() == arg.String()
-			case uintKind:
-				truth = arg1.Uint() == arg.Uint()
-			default:
-				if arg == zero || arg1 == zero {
-					truth = arg1 == arg
-				} else {
-					if t2 := arg.Type(); !t2.Comparable() {
-						return false, fmt.Errorf("uncomparable type %s: %v", t2, arg)
-					}
-					truth = arg1.Interface() == arg.Interface()
-				}
-			}
-		}
-		if truth {
-			return true, nil
-		}
-	}
-	return false, nil
-}
-
-// ne evaluates the comparison a != b.
-func ne(arg1, arg2 reflect.Value) (bool, error) {
-	// != is the inverse of ==.
-	equal, err := eq(arg1, arg2)
-	return !equal, err
-}
-
-// lt evaluates the comparison a < b.
-func lt(arg1, arg2 reflect.Value) (bool, error) {
-	arg1 = indirectInterface(arg1)
-	k1, err := basicKind(arg1)
-	if err != nil {
-		return false, err
-	}
-	arg2 = indirectInterface(arg2)
-	k2, err := basicKind(arg2)
-	if err != nil {
-		return false, err
-	}
-	truth := false
-	if k1 != k2 {
-		// Special case: Can compare integer values regardless of type's sign.
-		switch {
-		case k1 == intKind && k2 == uintKind:
-			truth = arg1.Int() < 0 || uint64(arg1.Int()) < arg2.Uint()
-		case k1 == uintKind && k2 == intKind:
-			truth = arg2.Int() >= 0 && arg1.Uint() < uint64(arg2.Int())
-		default:
-			return false, errBadComparison
-		}
-	} else {
-		switch k1 {
-		case boolKind, complexKind:
-			return false, errBadComparisonType
-		case floatKind:
-			truth = arg1.Float() < arg2.Float()
-		case intKind:
-			truth = arg1.Int() < arg2.Int()
-		case stringKind:
-			truth = arg1.String() < arg2.String()
-		case uintKind:
-			truth = arg1.Uint() < arg2.Uint()
-		default:
-			panic("invalid kind")
-		}
-	}
-	return truth, nil
-}
-
-// le evaluates the comparison <= b.
-func le(arg1, arg2 reflect.Value) (bool, error) {
-	// <= is < or ==.
-	lessThan, err := lt(arg1, arg2)
-	if lessThan || err != nil {
-		return lessThan, err
-	}
-	return eq(arg1, arg2)
-}
-
-// gt evaluates the comparison a > b.
-func gt(arg1, arg2 reflect.Value) (bool, error) {
-	// > is the inverse of <=.
-	lessOrEqual, err := le(arg1, arg2)
-	if err != nil {
-		return false, err
-	}
-	return !lessOrEqual, nil
-}
-
-// ge evaluates the comparison a >= b.
-func ge(arg1, arg2 reflect.Value) (bool, error) {
-	// >= is the inverse of <.
-	lessThan, err := lt(arg1, arg2)
-	if err != nil {
-		return false, err
-	}
-	return !lessThan, nil
-}
-
-// HTML escaping.
-
-var (
-	htmlQuot = []byte("&#34;") // shorter than "&quot;"
-	htmlApos = []byte("&#39;") // shorter than "&apos;" and apos was not in HTML until HTML5
-	htmlAmp  = []byte("&amp;")
-	htmlLt   = []byte("&lt;")
-	htmlGt   = []byte("&gt;")
-	htmlNull = []byte("\uFFFD")
-)
-
-// HTMLEscape writes to w the escaped HTML equivalent of the plain text data b.
-func HTMLEscape(w io.Writer, b []byte) {
-	last := 0
-	for i, c := range b {
-		var html []byte
-		switch c {
-		case '\000':
-			html = htmlNull
-		case '"':
-			html = htmlQuot
-		case '\'':
-			html = htmlApos
-		case '&':
-			html = htmlAmp
-		case '<':
-			html = htmlLt
-		case '>':
-			html = htmlGt
-		default:
-			continue
-		}
-		w.Write(b[last:i])
-		w.Write(html)
-		last = i + 1
-	}
-	w.Write(b[last:])
-}
-
-// HTMLEscapeString returns the escaped HTML equivalent of the plain text data s.
-func HTMLEscapeString(s string) string {
-	// Avoid allocation if we can.
-	if !strings.ContainsAny(s, "'\"&<>\000") {
-		return s
-	}
-	var b bytes.Buffer
-	HTMLEscape(&b, []byte(s))
-	return b.String()
-}
-
-// HTMLEscaper returns the escaped HTML equivalent of the textual
-// representation of its arguments.
-func HTMLEscaper(args ...any) string {
-	return HTMLEscapeString(evalArgs(args))
-}
-
-// JavaScript escaping.
-
-var (
-	jsLowUni = []byte(`\u00`)
-	hex      = []byte("0123456789ABCDEF")
-
-	jsBackslash = []byte(`\\`)
-	jsApos      = []byte(`\'`)
-	jsQuot      = []byte(`\"`)
-	jsLt        = []byte(`\u003C`)
-	jsGt        = []byte(`\u003E`)
-	jsAmp       = []byte(`\u0026`)
-	jsEq        = []byte(`\u003D`)
-)
-
-// JSEscape writes to w the escaped JavaScript equivalent of the plain text data b.
-func JSEscape(w io.Writer, b []byte) {
-	last := 0
-	for i := 0; i < len(b); i++ {
-		c := b[i]
-
-		if !jsIsSpecial(rune(c)) {
-			// fast path: nothing to do
-			continue
-		}
-		w.Write(b[last:i])
-
-		if c < utf8.RuneSelf {
-			// Quotes, slashes and angle brackets get quoted.
-			// Control characters get written as \u00XX.
-			switch c {
-			case '\\':
-				w.Write(jsBackslash)
-			case '\'':
-				w.Write(jsApos)
-			case '"':
-				w.Write(jsQuot)
-			case '<':
-				w.Write(jsLt)
-			case '>':
-				w.Write(jsGt)
-			case '&':
-				w.Write(jsAmp)
-			case '=':
-				w.Write(jsEq)
-			default:
-				w.Write(jsLowUni)
-				t, b := c>>4, c&0x0f
-				w.Write(hex[t : t+1])
-				w.Write(hex[b : b+1])
-			}
-		} else {
-			// Unicode rune.
-			r, size := utf8.DecodeRune(b[i:])
-			if unicode.IsPrint(r) {
-				w.Write(b[i : i+size])
-			} else {
-				fmt.Fprintf(w, "\\u%04X", r)
-			}
-			i += size - 1
-		}
-		last = i + 1
-	}
-	w.Write(b[last:])
-}
-
-// JSEscapeString returns the escaped JavaScript equivalent of the plain text data s.
-func JSEscapeString(s string) string {
-	// Avoid allocation if we can.
-	if strings.IndexFunc(s, jsIsSpecial) < 0 {
-		return s
-	}
-	var b bytes.Buffer
-	JSEscape(&b, []byte(s))
-	return b.String()
-}
-
-func jsIsSpecial(r rune) bool {
-	switch r {
-	case '\\', '\'', '"', '<', '>', '&', '=':
-		return true
-	}
-	return r < ' ' || utf8.RuneSelf <= r
-}
-
-// JSEscaper returns the escaped JavaScript equivalent of the textual
-// representation of its arguments.
-func JSEscaper(args ...any) string {
-	return JSEscapeString(evalArgs(args))
-}
-
-// URLQueryEscaper returns the escaped value of the textual representation of
-// its arguments in a form suitable for embedding in a URL query.
-func URLQueryEscaper(args ...any) string {
-	return url.QueryEscape(evalArgs(args))
-}
-
-// evalArgs formats the list of arguments into a string. It is therefore equivalent to
-//	fmt.Sprint(args...)
-// except that each argument is indirected (if a pointer), as required,
-// using the same rules as the default string evaluation during template
-// execution.
-func evalArgs(args []any) string {
-	ok := false
-	var s string
-	// Fast path for simple common case.
-	if len(args) == 1 {
-		s, ok = args[0].(string)
-	}
-	if !ok {
-		for i, arg := range args {
-			a, ok := printableValue(reflect.ValueOf(arg))
-			if ok {
-				args[i] = a
-			} // else let fmt do its thing
-		}
-		s = fmt.Sprint(args...)
-	}
-	return s
-}
diff --git a/contrib/go/_std_1.18/src/text/template/helper.go b/contrib/go/_std_1.18/src/text/template/helper.go
deleted file mode 100644
index 57905e613a..0000000000
--- a/contrib/go/_std_1.18/src/text/template/helper.go
+++ /dev/null
@@ -1,177 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Helper functions to make constructing templates easier.
-
-package template
-
-import (
-	"fmt"
-	"io/fs"
-	"os"
-	"path"
-	"path/filepath"
-)
-
-// Functions and methods to parse templates.
-
-// Must is a helper that wraps a call to a function returning (*Template, error)
-// and panics if the error is non-nil. It is intended for use in variable
-// initializations such as
-//	var t = template.Must(template.New("name").Parse("text"))
-func Must(t *Template, err error) *Template {
-	if err != nil {
-		panic(err)
-	}
-	return t
-}
-
-// ParseFiles creates a new Template and parses the template definitions from
-// the named files. The returned template's name will have the base name and
-// parsed contents of the first file. There must be at least one file.
-// If an error occurs, parsing stops and the returned *Template is nil.
-//
-// When parsing multiple files with the same name in different directories,
-// the last one mentioned will be the one that results.
-// For instance, ParseFiles("a/foo", "b/foo") stores "b/foo" as the template
-// named "foo", while "a/foo" is unavailable.
-func ParseFiles(filenames ...string) (*Template, error) {
-	return parseFiles(nil, readFileOS, filenames...)
-}
-
-// ParseFiles parses the named files and associates the resulting templates with
-// t. If an error occurs, parsing stops and the returned template is nil;
-// otherwise it is t. There must be at least one file.
-// Since the templates created by ParseFiles are named by the base
-// names of the argument files, t should usually have the name of one
-// of the (base) names of the files. If it does not, depending on t's
-// contents before calling ParseFiles, t.Execute may fail. In that
-// case use t.ExecuteTemplate to execute a valid template.
-//
-// When parsing multiple files with the same name in different directories,
-// the last one mentioned will be the one that results.
-func (t *Template) ParseFiles(filenames ...string) (*Template, error) {
-	t.init()
-	return parseFiles(t, readFileOS, filenames...)
-}
-
-// parseFiles is the helper for the method and function. If the argument
-// template is nil, it is created from the first file.
-func parseFiles(t *Template, readFile func(string) (string, []byte, error), filenames ...string) (*Template, error) {
-	if len(filenames) == 0 {
-		// Not really a problem, but be consistent.
-		return nil, fmt.Errorf("template: no files named in call to ParseFiles")
-	}
-	for _, filename := range filenames {
-		name, b, err := readFile(filename)
-		if err != nil {
-			return nil, err
-		}
-		s := string(b)
-		// First template becomes return value if not already defined,
-		// and we use that one for subsequent New calls to associate
-		// all the templates together. Also, if this file has the same name
-		// as t, this file becomes the contents of t, so
-		//  t, err := New(name).Funcs(xxx).ParseFiles(name)
-		// works. Otherwise we create a new template associated with t.
-		var tmpl *Template
-		if t == nil {
-			t = New(name)
-		}
-		if name == t.Name() {
-			tmpl = t
-		} else {
-			tmpl = t.New(name)
-		}
-		_, err = tmpl.Parse(s)
-		if err != nil {
-			return nil, err
-		}
-	}
-	return t, nil
-}
-
-// ParseGlob creates a new Template and parses the template definitions from
-// the files identified by the pattern. The files are matched according to the
-// semantics of filepath.Match, and the pattern must match at least one file.
-// The returned template will have the (base) name and (parsed) contents of the
-// first file matched by the pattern. ParseGlob is equivalent to calling
-// ParseFiles with the list of files matched by the pattern.
-//
-// When parsing multiple files with the same name in different directories,
-// the last one mentioned will be the one that results.
-func ParseGlob(pattern string) (*Template, error) {
-	return parseGlob(nil, pattern)
-}
-
-// ParseGlob parses the template definitions in the files identified by the
-// pattern and associates the resulting templates with t. The files are matched
-// according to the semantics of filepath.Match, and the pattern must match at
-// least one file. ParseGlob is equivalent to calling t.ParseFiles with the
-// list of files matched by the pattern.
-//
-// When parsing multiple files with the same name in different directories,
-// the last one mentioned will be the one that results.
-func (t *Template) ParseGlob(pattern string) (*Template, error) {
-	t.init()
-	return parseGlob(t, pattern)
-}
-
-// parseGlob is the implementation of the function and method ParseGlob.
-func parseGlob(t *Template, pattern string) (*Template, error) {
-	filenames, err := filepath.Glob(pattern)
-	if err != nil {
-		return nil, err
-	}
-	if len(filenames) == 0 {
-		return nil, fmt.Errorf("template: pattern matches no files: %#q", pattern)
-	}
-	return parseFiles(t, readFileOS, filenames...)
-}
-
-// ParseFS is like ParseFiles or ParseGlob but reads from the file system fsys
-// instead of the host operating system's file system.
-// It accepts a list of glob patterns.
-// (Note that most file names serve as glob patterns matching only themselves.)
-func ParseFS(fsys fs.FS, patterns ...string) (*Template, error) {
-	return parseFS(nil, fsys, patterns)
-}
-
-// ParseFS is like ParseFiles or ParseGlob but reads from the file system fsys
-// instead of the host operating system's file system.
-// It accepts a list of glob patterns.
-// (Note that most file names serve as glob patterns matching only themselves.)
-func (t *Template) ParseFS(fsys fs.FS, patterns ...string) (*Template, error) {
-	t.init()
-	return parseFS(t, fsys, patterns)
-}
-
-func parseFS(t *Template, fsys fs.FS, patterns []string) (*Template, error) {
-	var filenames []string
-	for _, pattern := range patterns {
-		list, err := fs.Glob(fsys, pattern)
-		if err != nil {
-			return nil, err
-		}
-		if len(list) == 0 {
-			return nil, fmt.Errorf("template: pattern matches no files: %#q", pattern)
-		}
-		filenames = append(filenames, list...)
-	}
-	return parseFiles(t, readFileFS(fsys), filenames...)
-}
-
-func readFileOS(file string) (name string, b []byte, err error) {
-	name = filepath.Base(file)
-	b, err = os.ReadFile(file)
-	return
-}
-
-func readFileFS(fsys fs.FS) func(string) (string, []byte, error) {
-	return func(file string) (name string, b []byte, err error) {
-		name = path.Base(file)
-		b, err = fs.ReadFile(fsys, file)
-		return
-	}
-}
diff --git a/contrib/go/_std_1.18/src/text/template/option.go b/contrib/go/_std_1.18/src/text/template/option.go
deleted file mode 100644
index 1035afad72..0000000000
--- a/contrib/go/_std_1.18/src/text/template/option.go
+++ /dev/null
@@ -1,72 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file contains the code to handle template options.
-
-package template
-
-import "strings"
-
-// missingKeyAction defines how to respond to indexing a map with a key that is not present.
-type missingKeyAction int
-
-const (
-	mapInvalid   missingKeyAction = iota // Return an invalid reflect.Value.
-	mapZeroValue                         // Return the zero value for the map element.
-	mapError                             // Error out
-)
-
-type option struct {
-	missingKey missingKeyAction
-}
-
-// Option sets options for the template. Options are described by
-// strings, either a simple string or "key=value". There can be at
-// most one equals sign in an option string. If the option string
-// is unrecognized or otherwise invalid, Option panics.
-//
-// Known options:
-//
-// missingkey: Control the behavior during execution if a map is
-// indexed with a key that is not present in the map.
-//	"missingkey=default" or "missingkey=invalid"
-//		The default behavior: Do nothing and continue execution.
-//		If printed, the result of the index operation is the string
-//		"<no value>".
-//	"missingkey=zero"
-//		The operation returns the zero value for the map type's element.
-//	"missingkey=error"
-//		Execution stops immediately with an error.
-//
-func (t *Template) Option(opt ...string) *Template {
-	t.init()
-	for _, s := range opt {
-		t.setOption(s)
-	}
-	return t
-}
-
-func (t *Template) setOption(opt string) {
-	if opt == "" {
-		panic("empty option string")
-	}
-	// key=value
-	if key, value, ok := strings.Cut(opt, "="); ok {
-		switch key {
-		case "missingkey":
-			switch value {
-			case "invalid", "default":
-				t.option.missingKey = mapInvalid
-				return
-			case "zero":
-				t.option.missingKey = mapZeroValue
-				return
-			case "error":
-				t.option.missingKey = mapError
-				return
-			}
-		}
-	}
-	panic("unrecognized option: " + opt)
-}
diff --git a/contrib/go/_std_1.18/src/text/template/parse/lex.go b/contrib/go/_std_1.18/src/text/template/parse/lex.go
deleted file mode 100644
index 40d0411121..0000000000
--- a/contrib/go/_std_1.18/src/text/template/parse/lex.go
+++ /dev/null
@@ -1,682 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package parse
-
-import (
-	"fmt"
-	"strings"
-	"unicode"
-	"unicode/utf8"
-)
-
-// item represents a token or text string returned from the scanner.
-type item struct {
-	typ  itemType // The type of this item.
-	pos  Pos      // The starting position, in bytes, of this item in the input string.
-	val  string   // The value of this item.
-	line int      // The line number at the start of this item.
-}
-
-func (i item) String() string {
-	switch {
-	case i.typ == itemEOF:
-		return "EOF"
-	case i.typ == itemError:
-		return i.val
-	case i.typ > itemKeyword:
-		return fmt.Sprintf("<%s>", i.val)
-	case len(i.val) > 10:
-		return fmt.Sprintf("%.10q...", i.val)
-	}
-	return fmt.Sprintf("%q", i.val)
-}
-
-// itemType identifies the type of lex items.
-type itemType int
-
-const (
-	itemError        itemType = iota // error occurred; value is text of error
-	itemBool                         // boolean constant
-	itemChar                         // printable ASCII character; grab bag for comma etc.
-	itemCharConstant                 // character constant
-	itemComment                      // comment text
-	itemComplex                      // complex constant (1+2i); imaginary is just a number
-	itemAssign                       // equals ('=') introducing an assignment
-	itemDeclare                      // colon-equals (':=') introducing a declaration
-	itemEOF
-	itemField      // alphanumeric identifier starting with '.'
-	itemIdentifier // alphanumeric identifier not starting with '.'
-	itemLeftDelim  // left action delimiter
-	itemLeftParen  // '(' inside action
-	itemNumber     // simple number, including imaginary
-	itemPipe       // pipe symbol
-	itemRawString  // raw quoted string (includes quotes)
-	itemRightDelim // right action delimiter
-	itemRightParen // ')' inside action
-	itemSpace      // run of spaces separating arguments
-	itemString     // quoted string (includes quotes)
-	itemText       // plain text
-	itemVariable   // variable starting with '$', such as '$' or  '$1' or '$hello'
-	// Keywords appear after all the rest.
-	itemKeyword  // used only to delimit the keywords
-	itemBlock    // block keyword
-	itemBreak    // break keyword
-	itemContinue // continue keyword
-	itemDot      // the cursor, spelled '.'
-	itemDefine   // define keyword
-	itemElse     // else keyword
-	itemEnd      // end keyword
-	itemIf       // if keyword
-	itemNil      // the untyped nil constant, easiest to treat as a keyword
-	itemRange    // range keyword
-	itemTemplate // template keyword
-	itemWith     // with keyword
-)
-
-var key = map[string]itemType{
-	".":        itemDot,
-	"block":    itemBlock,
-	"break":    itemBreak,
-	"continue": itemContinue,
-	"define":   itemDefine,
-	"else":     itemElse,
-	"end":      itemEnd,
-	"if":       itemIf,
-	"range":    itemRange,
-	"nil":      itemNil,
-	"template": itemTemplate,
-	"with":     itemWith,
-}
-
-const eof = -1
-
-// Trimming spaces.
-// If the action begins "{{- " rather than "{{", then all space/tab/newlines
-// preceding the action are trimmed; conversely if it ends " -}}" the
-// leading spaces are trimmed. This is done entirely in the lexer; the
-// parser never sees it happen. We require an ASCII space (' ', \t, \r, \n)
-// to be present to avoid ambiguity with things like "{{-3}}". It reads
-// better with the space present anyway. For simplicity, only ASCII
-// does the job.
-const (
-	spaceChars    = " \t\r\n"  // These are the space characters defined by Go itself.
-	trimMarker    = '-'        // Attached to left/right delimiter, trims trailing spaces from preceding/following text.
-	trimMarkerLen = Pos(1 + 1) // marker plus space before or after
-)
-
-// stateFn represents the state of the scanner as a function that returns the next state.
-type stateFn func(*lexer) stateFn
-
-// lexer holds the state of the scanner.
-type lexer struct {
-	name        string    // the name of the input; used only for error reports
-	input       string    // the string being scanned
-	leftDelim   string    // start of action
-	rightDelim  string    // end of action
-	emitComment bool      // emit itemComment tokens.
-	pos         Pos       // current position in the input
-	start       Pos       // start position of this item
-	width       Pos       // width of last rune read from input
-	items       chan item // channel of scanned items
-	parenDepth  int       // nesting depth of ( ) exprs
-	line        int       // 1+number of newlines seen
-	startLine   int       // start line of this item
-	breakOK     bool      // break keyword allowed
-	continueOK  bool      // continue keyword allowed
-}
-
-// next returns the next rune in the input.
-func (l *lexer) next() rune {
-	if int(l.pos) >= len(l.input) {
-		l.width = 0
-		return eof
-	}
-	r, w := utf8.DecodeRuneInString(l.input[l.pos:])
-	l.width = Pos(w)
-	l.pos += l.width
-	if r == '\n' {
-		l.line++
-	}
-	return r
-}
-
-// peek returns but does not consume the next rune in the input.
-func (l *lexer) peek() rune {
-	r := l.next()
-	l.backup()
-	return r
-}
-
-// backup steps back one rune. Can only be called once per call of next.
-func (l *lexer) backup() {
-	l.pos -= l.width
-	// Correct newline count.
-	if l.width == 1 && l.input[l.pos] == '\n' {
-		l.line--
-	}
-}
-
-// emit passes an item back to the client.
-func (l *lexer) emit(t itemType) {
-	l.items <- item{t, l.start, l.input[l.start:l.pos], l.startLine}
-	l.start = l.pos
-	l.startLine = l.line
-}
-
-// ignore skips over the pending input before this point.
-func (l *lexer) ignore() {
-	l.line += strings.Count(l.input[l.start:l.pos], "\n")
-	l.start = l.pos
-	l.startLine = l.line
-}
-
-// accept consumes the next rune if it's from the valid set.
-func (l *lexer) accept(valid string) bool {
-	if strings.ContainsRune(valid, l.next()) {
-		return true
-	}
-	l.backup()
-	return false
-}
-
-// acceptRun consumes a run of runes from the valid set.
-func (l *lexer) acceptRun(valid string) {
-	for strings.ContainsRune(valid, l.next()) {
-	}
-	l.backup()
-}
-
-// errorf returns an error token and terminates the scan by passing
-// back a nil pointer that will be the next state, terminating l.nextItem.
-func (l *lexer) errorf(format string, args ...any) stateFn {
-	l.items <- item{itemError, l.start, fmt.Sprintf(format, args...), l.startLine}
-	return nil
-}
-
-// nextItem returns the next item from the input.
-// Called by the parser, not in the lexing goroutine.
-func (l *lexer) nextItem() item {
-	return <-l.items
-}
-
-// drain drains the output so the lexing goroutine will exit.
-// Called by the parser, not in the lexing goroutine.
-func (l *lexer) drain() {
-	for range l.items {
-	}
-}
-
-// lex creates a new scanner for the input string.
-func lex(name, input, left, right string, emitComment bool) *lexer {
-	if left == "" {
-		left = leftDelim
-	}
-	if right == "" {
-		right = rightDelim
-	}
-	l := &lexer{
-		name:        name,
-		input:       input,
-		leftDelim:   left,
-		rightDelim:  right,
-		emitComment: emitComment,
-		items:       make(chan item),
-		line:        1,
-		startLine:   1,
-	}
-	go l.run()
-	return l
-}
-
-// run runs the state machine for the lexer.
-func (l *lexer) run() {
-	for state := lexText; state != nil; {
-		state = state(l)
-	}
-	close(l.items)
-}
-
-// state functions
-
-const (
-	leftDelim    = "{{"
-	rightDelim   = "}}"
-	leftComment  = "/*"
-	rightComment = "*/"
-)
-
-// lexText scans until an opening action delimiter, "{{".
-func lexText(l *lexer) stateFn {
-	l.width = 0
-	if x := strings.Index(l.input[l.pos:], l.leftDelim); x >= 0 {
-		ldn := Pos(len(l.leftDelim))
-		l.pos += Pos(x)
-		trimLength := Pos(0)
-		if hasLeftTrimMarker(l.input[l.pos+ldn:]) {
-			trimLength = rightTrimLength(l.input[l.start:l.pos])
-		}
-		l.pos -= trimLength
-		if l.pos > l.start {
-			l.line += strings.Count(l.input[l.start:l.pos], "\n")
-			l.emit(itemText)
-		}
-		l.pos += trimLength
-		l.ignore()
-		return lexLeftDelim
-	}
-	l.pos = Pos(len(l.input))
-	// Correctly reached EOF.
-	if l.pos > l.start {
-		l.line += strings.Count(l.input[l.start:l.pos], "\n")
-		l.emit(itemText)
-	}
-	l.emit(itemEOF)
-	return nil
-}
-
-// rightTrimLength returns the length of the spaces at the end of the string.
-func rightTrimLength(s string) Pos {
-	return Pos(len(s) - len(strings.TrimRight(s, spaceChars)))
-}
-
-// atRightDelim reports whether the lexer is at a right delimiter, possibly preceded by a trim marker.
-func (l *lexer) atRightDelim() (delim, trimSpaces bool) {
-	if hasRightTrimMarker(l.input[l.pos:]) && strings.HasPrefix(l.input[l.pos+trimMarkerLen:], l.rightDelim) { // With trim marker.
-		return true, true
-	}
-	if strings.HasPrefix(l.input[l.pos:], l.rightDelim) { // Without trim marker.
-		return true, false
-	}
-	return false, false
-}
-
-// leftTrimLength returns the length of the spaces at the beginning of the string.
-func leftTrimLength(s string) Pos {
-	return Pos(len(s) - len(strings.TrimLeft(s, spaceChars)))
-}
-
-// lexLeftDelim scans the left delimiter, which is known to be present, possibly with a trim marker.
-func lexLeftDelim(l *lexer) stateFn {
-	l.pos += Pos(len(l.leftDelim))
-	trimSpace := hasLeftTrimMarker(l.input[l.pos:])
-	afterMarker := Pos(0)
-	if trimSpace {
-		afterMarker = trimMarkerLen
-	}
-	if strings.HasPrefix(l.input[l.pos+afterMarker:], leftComment) {
-		l.pos += afterMarker
-		l.ignore()
-		return lexComment
-	}
-	l.emit(itemLeftDelim)
-	l.pos += afterMarker
-	l.ignore()
-	l.parenDepth = 0
-	return lexInsideAction
-}
-
-// lexComment scans a comment. The left comment marker is known to be present.
-func lexComment(l *lexer) stateFn {
-	l.pos += Pos(len(leftComment))
-	i := strings.Index(l.input[l.pos:], rightComment)
-	if i < 0 {
-		return l.errorf("unclosed comment")
-	}
-	l.pos += Pos(i + len(rightComment))
-	delim, trimSpace := l.atRightDelim()
-	if !delim {
-		return l.errorf("comment ends before closing delimiter")
-	}
-	if l.emitComment {
-		l.emit(itemComment)
-	}
-	if trimSpace {
-		l.pos += trimMarkerLen
-	}
-	l.pos += Pos(len(l.rightDelim))
-	if trimSpace {
-		l.pos += leftTrimLength(l.input[l.pos:])
-	}
-	l.ignore()
-	return lexText
-}
-
-// lexRightDelim scans the right delimiter, which is known to be present, possibly with a trim marker.
-func lexRightDelim(l *lexer) stateFn {
-	trimSpace := hasRightTrimMarker(l.input[l.pos:])
-	if trimSpace {
-		l.pos += trimMarkerLen
-		l.ignore()
-	}
-	l.pos += Pos(len(l.rightDelim))
-	l.emit(itemRightDelim)
-	if trimSpace {
-		l.pos += leftTrimLength(l.input[l.pos:])
-		l.ignore()
-	}
-	return lexText
-}
-
-// lexInsideAction scans the elements inside action delimiters.
-func lexInsideAction(l *lexer) stateFn {
-	// Either number, quoted string, or identifier.
-	// Spaces separate arguments; runs of spaces turn into itemSpace.
-	// Pipe symbols separate and are emitted.
-	delim, _ := l.atRightDelim()
-	if delim {
-		if l.parenDepth == 0 {
-			return lexRightDelim
-		}
-		return l.errorf("unclosed left paren")
-	}
-	switch r := l.next(); {
-	case r == eof:
-		return l.errorf("unclosed action")
-	case isSpace(r):
-		l.backup() // Put space back in case we have " -}}".
-		return lexSpace
-	case r == '=':
-		l.emit(itemAssign)
-	case r == ':':
-		if l.next() != '=' {
-			return l.errorf("expected :=")
-		}
-		l.emit(itemDeclare)
-	case r == '|':
-		l.emit(itemPipe)
-	case r == '"':
-		return lexQuote
-	case r == '`':
-		return lexRawQuote
-	case r == '$':
-		return lexVariable
-	case r == '\'':
-		return lexChar
-	case r == '.':
-		// special look-ahead for ".field" so we don't break l.backup().
-		if l.pos < Pos(len(l.input)) {
-			r := l.input[l.pos]
-			if r < '0' || '9' < r {
-				return lexField
-			}
-		}
-		fallthrough // '.' can start a number.
-	case r == '+' || r == '-' || ('0' <= r && r <= '9'):
-		l.backup()
-		return lexNumber
-	case isAlphaNumeric(r):
-		l.backup()
-		return lexIdentifier
-	case r == '(':
-		l.emit(itemLeftParen)
-		l.parenDepth++
-	case r == ')':
-		l.emit(itemRightParen)
-		l.parenDepth--
-		if l.parenDepth < 0 {
-			return l.errorf("unexpected right paren %#U", r)
-		}
-	case r <= unicode.MaxASCII && unicode.IsPrint(r):
-		l.emit(itemChar)
-	default:
-		return l.errorf("unrecognized character in action: %#U", r)
-	}
-	return lexInsideAction
-}
-
-// lexSpace scans a run of space characters.
-// We have not consumed the first space, which is known to be present.
-// Take care if there is a trim-marked right delimiter, which starts with a space.
-func lexSpace(l *lexer) stateFn {
-	var r rune
-	var numSpaces int
-	for {
-		r = l.peek()
-		if !isSpace(r) {
-			break
-		}
-		l.next()
-		numSpaces++
-	}
-	// Be careful about a trim-marked closing delimiter, which has a minus
-	// after a space. We know there is a space, so check for the '-' that might follow.
-	if hasRightTrimMarker(l.input[l.pos-1:]) && strings.HasPrefix(l.input[l.pos-1+trimMarkerLen:], l.rightDelim) {
-		l.backup() // Before the space.
-		if numSpaces == 1 {
-			return lexRightDelim // On the delim, so go right to that.
-		}
-	}
-	l.emit(itemSpace)
-	return lexInsideAction
-}
-
-// lexIdentifier scans an alphanumeric.
-func lexIdentifier(l *lexer) stateFn {
-Loop:
-	for {
-		switch r := l.next(); {
-		case isAlphaNumeric(r):
-			// absorb.
-		default:
-			l.backup()
-			word := l.input[l.start:l.pos]
-			if !l.atTerminator() {
-				return l.errorf("bad character %#U", r)
-			}
-			switch {
-			case key[word] > itemKeyword:
-				item := key[word]
-				if item == itemBreak && !l.breakOK || item == itemContinue && !l.continueOK {
-					l.emit(itemIdentifier)
-				} else {
-					l.emit(item)
-				}
-			case word[0] == '.':
-				l.emit(itemField)
-			case word == "true", word == "false":
-				l.emit(itemBool)
-			default:
-				l.emit(itemIdentifier)
-			}
-			break Loop
-		}
-	}
-	return lexInsideAction
-}
-
-// lexField scans a field: .Alphanumeric.
-// The . has been scanned.
-func lexField(l *lexer) stateFn {
-	return lexFieldOrVariable(l, itemField)
-}
-
-// lexVariable scans a Variable: $Alphanumeric.
-// The $ has been scanned.
-func lexVariable(l *lexer) stateFn {
-	if l.atTerminator() { // Nothing interesting follows -> "$".
-		l.emit(itemVariable)
-		return lexInsideAction
-	}
-	return lexFieldOrVariable(l, itemVariable)
-}
-
-// lexVariable scans a field or variable: [.$]Alphanumeric.
-// The . or $ has been scanned.
-func lexFieldOrVariable(l *lexer, typ itemType) stateFn {
-	if l.atTerminator() { // Nothing interesting follows -> "." or "$".
-		if typ == itemVariable {
-			l.emit(itemVariable)
-		} else {
-			l.emit(itemDot)
-		}
-		return lexInsideAction
-	}
-	var r rune
-	for {
-		r = l.next()
-		if !isAlphaNumeric(r) {
-			l.backup()
-			break
-		}
-	}
-	if !l.atTerminator() {
-		return l.errorf("bad character %#U", r)
-	}
-	l.emit(typ)
-	return lexInsideAction
-}
-
-// atTerminator reports whether the input is at valid termination character to
-// appear after an identifier. Breaks .X.Y into two pieces. Also catches cases
-// like "$x+2" not being acceptable without a space, in case we decide one
-// day to implement arithmetic.
-func (l *lexer) atTerminator() bool {
-	r := l.peek()
-	if isSpace(r) {
-		return true
-	}
-	switch r {
-	case eof, '.', ',', '|', ':', ')', '(':
-		return true
-	}
-	// Does r start the delimiter? This can be ambiguous (with delim=="//", $x/2 will
-	// succeed but should fail) but only in extremely rare cases caused by willfully
-	// bad choice of delimiter.
-	if rd, _ := utf8.DecodeRuneInString(l.rightDelim); rd == r {
-		return true
-	}
-	return false
-}
-
-// lexChar scans a character constant. The initial quote is already
-// scanned. Syntax checking is done by the parser.
-func lexChar(l *lexer) stateFn {
-Loop:
-	for {
-		switch l.next() {
-		case '\\':
-			if r := l.next(); r != eof && r != '\n' {
-				break
-			}
-			fallthrough
-		case eof, '\n':
-			return l.errorf("unterminated character constant")
-		case '\'':
-			break Loop
-		}
-	}
-	l.emit(itemCharConstant)
-	return lexInsideAction
-}
-
-// lexNumber scans a number: decimal, octal, hex, float, or imaginary. This
-// isn't a perfect number scanner - for instance it accepts "." and "0x0.2"
-// and "089" - but when it's wrong the input is invalid and the parser (via
-// strconv) will notice.
-func lexNumber(l *lexer) stateFn {
-	if !l.scanNumber() {
-		return l.errorf("bad number syntax: %q", l.input[l.start:l.pos])
-	}
-	if sign := l.peek(); sign == '+' || sign == '-' {
-		// Complex: 1+2i. No spaces, must end in 'i'.
-		if !l.scanNumber() || l.input[l.pos-1] != 'i' {
-			return l.errorf("bad number syntax: %q", l.input[l.start:l.pos])
-		}
-		l.emit(itemComplex)
-	} else {
-		l.emit(itemNumber)
-	}
-	return lexInsideAction
-}
-
-func (l *lexer) scanNumber() bool {
-	// Optional leading sign.
-	l.accept("+-")
-	// Is it hex?
-	digits := "0123456789_"
-	if l.accept("0") {
-		// Note: Leading 0 does not mean octal in floats.
-		if l.accept("xX") {
-			digits = "0123456789abcdefABCDEF_"
-		} else if l.accept("oO") {
-			digits = "01234567_"
-		} else if l.accept("bB") {
-			digits = "01_"
-		}
-	}
-	l.acceptRun(digits)
-	if l.accept(".") {
-		l.acceptRun(digits)
-	}
-	if len(digits) == 10+1 && l.accept("eE") {
-		l.accept("+-")
-		l.acceptRun("0123456789_")
-	}
-	if len(digits) == 16+6+1 && l.accept("pP") {
-		l.accept("+-")
-		l.acceptRun("0123456789_")
-	}
-	// Is it imaginary?
-	l.accept("i")
-	// Next thing mustn't be alphanumeric.
-	if isAlphaNumeric(l.peek()) {
-		l.next()
-		return false
-	}
-	return true
-}
-
-// lexQuote scans a quoted string.
-func lexQuote(l *lexer) stateFn {
-Loop:
-	for {
-		switch l.next() {
-		case '\\':
-			if r := l.next(); r != eof && r != '\n' {
-				break
-			}
-			fallthrough
-		case eof, '\n':
-			return l.errorf("unterminated quoted string")
-		case '"':
-			break Loop
-		}
-	}
-	l.emit(itemString)
-	return lexInsideAction
-}
-
-// lexRawQuote scans a raw quoted string.
-func lexRawQuote(l *lexer) stateFn {
-Loop:
-	for {
-		switch l.next() {
-		case eof:
-			return l.errorf("unterminated raw quoted string")
-		case '`':
-			break Loop
-		}
-	}
-	l.emit(itemRawString)
-	return lexInsideAction
-}
-
-// isSpace reports whether r is a space character.
-func isSpace(r rune) bool {
-	return r == ' ' || r == '\t' || r == '\r' || r == '\n'
-}
-
-// isAlphaNumeric reports whether r is an alphabetic, digit, or underscore.
-func isAlphaNumeric(r rune) bool {
-	return r == '_' || unicode.IsLetter(r) || unicode.IsDigit(r)
-}
-
-func hasLeftTrimMarker(s string) bool {
-	return len(s) >= 2 && s[0] == trimMarker && isSpace(rune(s[1]))
-}
-
-func hasRightTrimMarker(s string) bool {
-	return len(s) >= 2 && isSpace(rune(s[0])) && s[1] == trimMarker
-}
diff --git a/contrib/go/_std_1.18/src/text/template/parse/parse.go b/contrib/go/_std_1.18/src/text/template/parse/parse.go
deleted file mode 100644
index ce548b0886..0000000000
--- a/contrib/go/_std_1.18/src/text/template/parse/parse.go
+++ /dev/null
@@ -1,795 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package parse builds parse trees for templates as defined by text/template
-// and html/template. Clients should use those packages to construct templates
-// rather than this one, which provides shared internal data structures not
-// intended for general use.
-package parse
-
-import (
-	"bytes"
-	"fmt"
-	"runtime"
-	"strconv"
-	"strings"
-)
-
-// Tree is the representation of a single parsed template.
-type Tree struct {
-	Name      string    // name of the template represented by the tree.
-	ParseName string    // name of the top-level template during parsing, for error messages.
-	Root      *ListNode // top-level root of the tree.
-	Mode      Mode      // parsing mode.
-	text      string    // text parsed to create the template (or its parent)
-	// Parsing only; cleared after parse.
-	funcs      []map[string]any
-	lex        *lexer
-	token      [3]item // three-token lookahead for parser.
-	peekCount  int
-	vars       []string // variables defined at the moment.
-	treeSet    map[string]*Tree
-	actionLine int // line of left delim starting action
-	rangeDepth int
-}
-
-// A mode value is a set of flags (or 0). Modes control parser behavior.
-type Mode uint
-
-const (
-	ParseComments Mode = 1 << iota // parse comments and add them to AST
-	SkipFuncCheck                  // do not check that functions are defined
-)
-
-// Copy returns a copy of the Tree. Any parsing state is discarded.
-func (t *Tree) Copy() *Tree {
-	if t == nil {
-		return nil
-	}
-	return &Tree{
-		Name:      t.Name,
-		ParseName: t.ParseName,
-		Root:      t.Root.CopyList(),
-		text:      t.text,
-	}
-}
-
-// Parse returns a map from template name to parse.Tree, created by parsing the
-// templates described in the argument string. The top-level template will be
-// given the specified name. If an error is encountered, parsing stops and an
-// empty map is returned with the error.
-func Parse(name, text, leftDelim, rightDelim string, funcs ...map[string]any) (map[string]*Tree, error) {
-	treeSet := make(map[string]*Tree)
-	t := New(name)
-	t.text = text
-	_, err := t.Parse(text, leftDelim, rightDelim, treeSet, funcs...)
-	return treeSet, err
-}
-
-// next returns the next token.
-func (t *Tree) next() item {
-	if t.peekCount > 0 {
-		t.peekCount--
-	} else {
-		t.token[0] = t.lex.nextItem()
-	}
-	return t.token[t.peekCount]
-}
-
-// backup backs the input stream up one token.
-func (t *Tree) backup() {
-	t.peekCount++
-}
-
-// backup2 backs the input stream up two tokens.
-// The zeroth token is already there.
-func (t *Tree) backup2(t1 item) {
-	t.token[1] = t1
-	t.peekCount = 2
-}
-
-// backup3 backs the input stream up three tokens
-// The zeroth token is already there.
-func (t *Tree) backup3(t2, t1 item) { // Reverse order: we're pushing back.
-	t.token[1] = t1
-	t.token[2] = t2
-	t.peekCount = 3
-}
-
-// peek returns but does not consume the next token.
-func (t *Tree) peek() item {
-	if t.peekCount > 0 {
-		return t.token[t.peekCount-1]
-	}
-	t.peekCount = 1
-	t.token[0] = t.lex.nextItem()
-	return t.token[0]
-}
-
-// nextNonSpace returns the next non-space token.
-func (t *Tree) nextNonSpace() (token item) {
-	for {
-		token = t.next()
-		if token.typ != itemSpace {
-			break
-		}
-	}
-	return token
-}
-
-// peekNonSpace returns but does not consume the next non-space token.
-func (t *Tree) peekNonSpace() item {
-	token := t.nextNonSpace()
-	t.backup()
-	return token
-}
-
-// Parsing.
-
-// New allocates a new parse tree with the given name.
-func New(name string, funcs ...map[string]any) *Tree {
-	return &Tree{
-		Name:  name,
-		funcs: funcs,
-	}
-}
-
-// ErrorContext returns a textual representation of the location of the node in the input text.
-// The receiver is only used when the node does not have a pointer to the tree inside,
-// which can occur in old code.
-func (t *Tree) ErrorContext(n Node) (location, context string) {
-	pos := int(n.Position())
-	tree := n.tree()
-	if tree == nil {
-		tree = t
-	}
-	text := tree.text[:pos]
-	byteNum := strings.LastIndex(text, "\n")
-	if byteNum == -1 {
-		byteNum = pos // On first line.
-	} else {
-		byteNum++ // After the newline.
-		byteNum = pos - byteNum
-	}
-	lineNum := 1 + strings.Count(text, "\n")
-	context = n.String()
-	return fmt.Sprintf("%s:%d:%d", tree.ParseName, lineNum, byteNum), context
-}
-
-// errorf formats the error and terminates processing.
-func (t *Tree) errorf(format string, args ...any) {
-	t.Root = nil
-	format = fmt.Sprintf("template: %s:%d: %s", t.ParseName, t.token[0].line, format)
-	panic(fmt.Errorf(format, args...))
-}
-
-// error terminates processing.
-func (t *Tree) error(err error) {
-	t.errorf("%s", err)
-}
-
-// expect consumes the next token and guarantees it has the required type.
-func (t *Tree) expect(expected itemType, context string) item {
-	token := t.nextNonSpace()
-	if token.typ != expected {
-		t.unexpected(token, context)
-	}
-	return token
-}
-
-// expectOneOf consumes the next token and guarantees it has one of the required types.
-func (t *Tree) expectOneOf(expected1, expected2 itemType, context string) item {
-	token := t.nextNonSpace()
-	if token.typ != expected1 && token.typ != expected2 {
-		t.unexpected(token, context)
-	}
-	return token
-}
-
-// unexpected complains about the token and terminates processing.
-func (t *Tree) unexpected(token item, context string) {
-	if token.typ == itemError {
-		extra := ""
-		if t.actionLine != 0 && t.actionLine != token.line {
-			extra = fmt.Sprintf(" in action started at %s:%d", t.ParseName, t.actionLine)
-			if strings.HasSuffix(token.val, " action") {
-				extra = extra[len(" in action"):] // avoid "action in action"
-			}
-		}
-		t.errorf("%s%s", token, extra)
-	}
-	t.errorf("unexpected %s in %s", token, context)
-}
-
-// recover is the handler that turns panics into returns from the top level of Parse.
-func (t *Tree) recover(errp *error) {
-	e := recover()
-	if e != nil {
-		if _, ok := e.(runtime.Error); ok {
-			panic(e)
-		}
-		if t != nil {
-			t.lex.drain()
-			t.stopParse()
-		}
-		*errp = e.(error)
-	}
-}
-
-// startParse initializes the parser, using the lexer.
-func (t *Tree) startParse(funcs []map[string]any, lex *lexer, treeSet map[string]*Tree) {
-	t.Root = nil
-	t.lex = lex
-	t.vars = []string{"$"}
-	t.funcs = funcs
-	t.treeSet = treeSet
-	lex.breakOK = !t.hasFunction("break")
-	lex.continueOK = !t.hasFunction("continue")
-}
-
-// stopParse terminates parsing.
-func (t *Tree) stopParse() {
-	t.lex = nil
-	t.vars = nil
-	t.funcs = nil
-	t.treeSet = nil
-}
-
-// Parse parses the template definition string to construct a representation of
-// the template for execution. If either action delimiter string is empty, the
-// default ("{{" or "}}") is used. Embedded template definitions are added to
-// the treeSet map.
-func (t *Tree) Parse(text, leftDelim, rightDelim string, treeSet map[string]*Tree, funcs ...map[string]any) (tree *Tree, err error) {
-	defer t.recover(&err)
-	t.ParseName = t.Name
-	emitComment := t.Mode&ParseComments != 0
-	t.startParse(funcs, lex(t.Name, text, leftDelim, rightDelim, emitComment), treeSet)
-	t.text = text
-	t.parse()
-	t.add()
-	t.stopParse()
-	return t, nil
-}
-
-// add adds tree to t.treeSet.
-func (t *Tree) add() {
-	tree := t.treeSet[t.Name]
-	if tree == nil || IsEmptyTree(tree.Root) {
-		t.treeSet[t.Name] = t
-		return
-	}
-	if !IsEmptyTree(t.Root) {
-		t.errorf("template: multiple definition of template %q", t.Name)
-	}
-}
-
-// IsEmptyTree reports whether this tree (node) is empty of everything but space or comments.
-func IsEmptyTree(n Node) bool {
-	switch n := n.(type) {
-	case nil:
-		return true
-	case *ActionNode:
-	case *CommentNode:
-		return true
-	case *IfNode:
-	case *ListNode:
-		for _, node := range n.Nodes {
-			if !IsEmptyTree(node) {
-				return false
-			}
-		}
-		return true
-	case *RangeNode:
-	case *TemplateNode:
-	case *TextNode:
-		return len(bytes.TrimSpace(n.Text)) == 0
-	case *WithNode:
-	default:
-		panic("unknown node: " + n.String())
-	}
-	return false
-}
-
-// parse is the top-level parser for a template, essentially the same
-// as itemList except it also parses {{define}} actions.
-// It runs to EOF.
-func (t *Tree) parse() {
-	t.Root = t.newList(t.peek().pos)
-	for t.peek().typ != itemEOF {
-		if t.peek().typ == itemLeftDelim {
-			delim := t.next()
-			if t.nextNonSpace().typ == itemDefine {
-				newT := New("definition") // name will be updated once we know it.
-				newT.text = t.text
-				newT.Mode = t.Mode
-				newT.ParseName = t.ParseName
-				newT.startParse(t.funcs, t.lex, t.treeSet)
-				newT.parseDefinition()
-				continue
-			}
-			t.backup2(delim)
-		}
-		switch n := t.textOrAction(); n.Type() {
-		case nodeEnd, nodeElse:
-			t.errorf("unexpected %s", n)
-		default:
-			t.Root.append(n)
-		}
-	}
-}
-
-// parseDefinition parses a {{define}} ...  {{end}} template definition and
-// installs the definition in t.treeSet. The "define" keyword has already
-// been scanned.
-func (t *Tree) parseDefinition() {
-	const context = "define clause"
-	name := t.expectOneOf(itemString, itemRawString, context)
-	var err error
-	t.Name, err = strconv.Unquote(name.val)
-	if err != nil {
-		t.error(err)
-	}
-	t.expect(itemRightDelim, context)
-	var end Node
-	t.Root, end = t.itemList()
-	if end.Type() != nodeEnd {
-		t.errorf("unexpected %s in %s", end, context)
-	}
-	t.add()
-	t.stopParse()
-}
-
-// itemList:
-//	textOrAction*
-// Terminates at {{end}} or {{else}}, returned separately.
-func (t *Tree) itemList() (list *ListNode, next Node) {
-	list = t.newList(t.peekNonSpace().pos)
-	for t.peekNonSpace().typ != itemEOF {
-		n := t.textOrAction()
-		switch n.Type() {
-		case nodeEnd, nodeElse:
-			return list, n
-		}
-		list.append(n)
-	}
-	t.errorf("unexpected EOF")
-	return
-}
-
-// textOrAction:
-//	text | comment | action
-func (t *Tree) textOrAction() Node {
-	switch token := t.nextNonSpace(); token.typ {
-	case itemText:
-		return t.newText(token.pos, token.val)
-	case itemLeftDelim:
-		t.actionLine = token.line
-		defer t.clearActionLine()
-		return t.action()
-	case itemComment:
-		return t.newComment(token.pos, token.val)
-	default:
-		t.unexpected(token, "input")
-	}
-	return nil
-}
-
-func (t *Tree) clearActionLine() {
-	t.actionLine = 0
-}
-
-// Action:
-//	control
-//	command ("|" command)*
-// Left delim is past. Now get actions.
-// First word could be a keyword such as range.
-func (t *Tree) action() (n Node) {
-	switch token := t.nextNonSpace(); token.typ {
-	case itemBlock:
-		return t.blockControl()
-	case itemBreak:
-		return t.breakControl(token.pos, token.line)
-	case itemContinue:
-		return t.continueControl(token.pos, token.line)
-	case itemElse:
-		return t.elseControl()
-	case itemEnd:
-		return t.endControl()
-	case itemIf:
-		return t.ifControl()
-	case itemRange:
-		return t.rangeControl()
-	case itemTemplate:
-		return t.templateControl()
-	case itemWith:
-		return t.withControl()
-	}
-	t.backup()
-	token := t.peek()
-	// Do not pop variables; they persist until "end".
-	return t.newAction(token.pos, token.line, t.pipeline("command", itemRightDelim))
-}
-
-// Break:
-//	{{break}}
-// Break keyword is past.
-func (t *Tree) breakControl(pos Pos, line int) Node {
-	if token := t.nextNonSpace(); token.typ != itemRightDelim {
-		t.unexpected(token, "{{break}}")
-	}
-	if t.rangeDepth == 0 {
-		t.errorf("{{break}} outside {{range}}")
-	}
-	return t.newBreak(pos, line)
-}
-
-// Continue:
-//	{{continue}}
-// Continue keyword is past.
-func (t *Tree) continueControl(pos Pos, line int) Node {
-	if token := t.nextNonSpace(); token.typ != itemRightDelim {
-		t.unexpected(token, "{{continue}}")
-	}
-	if t.rangeDepth == 0 {
-		t.errorf("{{continue}} outside {{range}}")
-	}
-	return t.newContinue(pos, line)
-}
-
-// Pipeline:
-//	declarations? command ('|' command)*
-func (t *Tree) pipeline(context string, end itemType) (pipe *PipeNode) {
-	token := t.peekNonSpace()
-	pipe = t.newPipeline(token.pos, token.line, nil)
-	// Are there declarations or assignments?
-decls:
-	if v := t.peekNonSpace(); v.typ == itemVariable {
-		t.next()
-		// Since space is a token, we need 3-token look-ahead here in the worst case:
-		// in "$x foo" we need to read "foo" (as opposed to ":=") to know that $x is an
-		// argument variable rather than a declaration. So remember the token
-		// adjacent to the variable so we can push it back if necessary.
-		tokenAfterVariable := t.peek()
-		next := t.peekNonSpace()
-		switch {
-		case next.typ == itemAssign, next.typ == itemDeclare:
-			pipe.IsAssign = next.typ == itemAssign
-			t.nextNonSpace()
-			pipe.Decl = append(pipe.Decl, t.newVariable(v.pos, v.val))
-			t.vars = append(t.vars, v.val)
-		case next.typ == itemChar && next.val == ",":
-			t.nextNonSpace()
-			pipe.Decl = append(pipe.Decl, t.newVariable(v.pos, v.val))
-			t.vars = append(t.vars, v.val)
-			if context == "range" && len(pipe.Decl) < 2 {
-				switch t.peekNonSpace().typ {
-				case itemVariable, itemRightDelim, itemRightParen:
-					// second initialized variable in a range pipeline
-					goto decls
-				default:
-					t.errorf("range can only initialize variables")
-				}
-			}
-			t.errorf("too many declarations in %s", context)
-		case tokenAfterVariable.typ == itemSpace:
-			t.backup3(v, tokenAfterVariable)
-		default:
-			t.backup2(v)
-		}
-	}
-	for {
-		switch token := t.nextNonSpace(); token.typ {
-		case end:
-			// At this point, the pipeline is complete
-			t.checkPipeline(pipe, context)
-			return
-		case itemBool, itemCharConstant, itemComplex, itemDot, itemField, itemIdentifier,
-			itemNumber, itemNil, itemRawString, itemString, itemVariable, itemLeftParen:
-			t.backup()
-			pipe.append(t.command())
-		default:
-			t.unexpected(token, context)
-		}
-	}
-}
-
-func (t *Tree) checkPipeline(pipe *PipeNode, context string) {
-	// Reject empty pipelines
-	if len(pipe.Cmds) == 0 {
-		t.errorf("missing value for %s", context)
-	}
-	// Only the first command of a pipeline can start with a non executable operand
-	for i, c := range pipe.Cmds[1:] {
-		switch c.Args[0].Type() {
-		case NodeBool, NodeDot, NodeNil, NodeNumber, NodeString:
-			// With A|B|C, pipeline stage 2 is B
-			t.errorf("non executable command in pipeline stage %d", i+2)
-		}
-	}
-}
-
-func (t *Tree) parseControl(allowElseIf bool, context string) (pos Pos, line int, pipe *PipeNode, list, elseList *ListNode) {
-	defer t.popVars(len(t.vars))
-	pipe = t.pipeline(context, itemRightDelim)
-	if context == "range" {
-		t.rangeDepth++
-	}
-	var next Node
-	list, next = t.itemList()
-	if context == "range" {
-		t.rangeDepth--
-	}
-	switch next.Type() {
-	case nodeEnd: //done
-	case nodeElse:
-		if allowElseIf {
-			// Special case for "else if". If the "else" is followed immediately by an "if",
-			// the elseControl will have left the "if" token pending. Treat
-			//	{{if a}}_{{else if b}}_{{end}}
-			// as
-			//	{{if a}}_{{else}}{{if b}}_{{end}}{{end}}.
-			// To do this, parse the if as usual and stop at it {{end}}; the subsequent{{end}}
-			// is assumed. This technique works even for long if-else-if chains.
-			// TODO: Should we allow else-if in with and range?
-			if t.peek().typ == itemIf {
-				t.next() // Consume the "if" token.
-				elseList = t.newList(next.Position())
-				elseList.append(t.ifControl())
-				// Do not consume the next item - only one {{end}} required.
-				break
-			}
-		}
-		elseList, next = t.itemList()
-		if next.Type() != nodeEnd {
-			t.errorf("expected end; found %s", next)
-		}
-	}
-	return pipe.Position(), pipe.Line, pipe, list, elseList
-}
-
-// If:
-//	{{if pipeline}} itemList {{end}}
-//	{{if pipeline}} itemList {{else}} itemList {{end}}
-// If keyword is past.
-func (t *Tree) ifControl() Node {
-	return t.newIf(t.parseControl(true, "if"))
-}
-
-// Range:
-//	{{range pipeline}} itemList {{end}}
-//	{{range pipeline}} itemList {{else}} itemList {{end}}
-// Range keyword is past.
-func (t *Tree) rangeControl() Node {
-	r := t.newRange(t.parseControl(false, "range"))
-	return r
-}
-
-// With:
-//	{{with pipeline}} itemList {{end}}
-//	{{with pipeline}} itemList {{else}} itemList {{end}}
-// If keyword is past.
-func (t *Tree) withControl() Node {
-	return t.newWith(t.parseControl(false, "with"))
-}
-
-// End:
-//	{{end}}
-// End keyword is past.
-func (t *Tree) endControl() Node {
-	return t.newEnd(t.expect(itemRightDelim, "end").pos)
-}
-
-// Else:
-//	{{else}}
-// Else keyword is past.
-func (t *Tree) elseControl() Node {
-	// Special case for "else if".
-	peek := t.peekNonSpace()
-	if peek.typ == itemIf {
-		// We see "{{else if ... " but in effect rewrite it to {{else}}{{if ... ".
-		return t.newElse(peek.pos, peek.line)
-	}
-	token := t.expect(itemRightDelim, "else")
-	return t.newElse(token.pos, token.line)
-}
-
-// Block:
-//	{{block stringValue pipeline}}
-// Block keyword is past.
-// The name must be something that can evaluate to a string.
-// The pipeline is mandatory.
-func (t *Tree) blockControl() Node {
-	const context = "block clause"
-
-	token := t.nextNonSpace()
-	name := t.parseTemplateName(token, context)
-	pipe := t.pipeline(context, itemRightDelim)
-
-	block := New(name) // name will be updated once we know it.
-	block.text = t.text
-	block.Mode = t.Mode
-	block.ParseName = t.ParseName
-	block.startParse(t.funcs, t.lex, t.treeSet)
-	var end Node
-	block.Root, end = block.itemList()
-	if end.Type() != nodeEnd {
-		t.errorf("unexpected %s in %s", end, context)
-	}
-	block.add()
-	block.stopParse()
-
-	return t.newTemplate(token.pos, token.line, name, pipe)
-}
-
-// Template:
-//	{{template stringValue pipeline}}
-// Template keyword is past. The name must be something that can evaluate
-// to a string.
-func (t *Tree) templateControl() Node {
-	const context = "template clause"
-	token := t.nextNonSpace()
-	name := t.parseTemplateName(token, context)
-	var pipe *PipeNode
-	if t.nextNonSpace().typ != itemRightDelim {
-		t.backup()
-		// Do not pop variables; they persist until "end".
-		pipe = t.pipeline(context, itemRightDelim)
-	}
-	return t.newTemplate(token.pos, token.line, name, pipe)
-}
-
-func (t *Tree) parseTemplateName(token item, context string) (name string) {
-	switch token.typ {
-	case itemString, itemRawString:
-		s, err := strconv.Unquote(token.val)
-		if err != nil {
-			t.error(err)
-		}
-		name = s
-	default:
-		t.unexpected(token, context)
-	}
-	return
-}
-
-// command:
-//	operand (space operand)*
-// space-separated arguments up to a pipeline character or right delimiter.
-// we consume the pipe character but leave the right delim to terminate the action.
-func (t *Tree) command() *CommandNode {
-	cmd := t.newCommand(t.peekNonSpace().pos)
-	for {
-		t.peekNonSpace() // skip leading spaces.
-		operand := t.operand()
-		if operand != nil {
-			cmd.append(operand)
-		}
-		switch token := t.next(); token.typ {
-		case itemSpace:
-			continue
-		case itemRightDelim, itemRightParen:
-			t.backup()
-		case itemPipe:
-			// nothing here; break loop below
-		default:
-			t.unexpected(token, "operand")
-		}
-		break
-	}
-	if len(cmd.Args) == 0 {
-		t.errorf("empty command")
-	}
-	return cmd
-}
-
-// operand:
-//	term .Field*
-// An operand is a space-separated component of a command,
-// a term possibly followed by field accesses.
-// A nil return means the next item is not an operand.
-func (t *Tree) operand() Node {
-	node := t.term()
-	if node == nil {
-		return nil
-	}
-	if t.peek().typ == itemField {
-		chain := t.newChain(t.peek().pos, node)
-		for t.peek().typ == itemField {
-			chain.Add(t.next().val)
-		}
-		// Compatibility with original API: If the term is of type NodeField
-		// or NodeVariable, just put more fields on the original.
-		// Otherwise, keep the Chain node.
-		// Obvious parsing errors involving literal values are detected here.
-		// More complex error cases will have to be handled at execution time.
-		switch node.Type() {
-		case NodeField:
-			node = t.newField(chain.Position(), chain.String())
-		case NodeVariable:
-			node = t.newVariable(chain.Position(), chain.String())
-		case NodeBool, NodeString, NodeNumber, NodeNil, NodeDot:
-			t.errorf("unexpected . after term %q", node.String())
-		default:
-			node = chain
-		}
-	}
-	return node
-}
-
-// term:
-//	literal (number, string, nil, boolean)
-//	function (identifier)
-//	.
-//	.Field
-//	$
-//	'(' pipeline ')'
-// A term is a simple "expression".
-// A nil return means the next item is not a term.
-func (t *Tree) term() Node {
-	switch token := t.nextNonSpace(); token.typ {
-	case itemIdentifier:
-		checkFunc := t.Mode&SkipFuncCheck == 0
-		if checkFunc && !t.hasFunction(token.val) {
-			t.errorf("function %q not defined", token.val)
-		}
-		return NewIdentifier(token.val).SetTree(t).SetPos(token.pos)
-	case itemDot:
-		return t.newDot(token.pos)
-	case itemNil:
-		return t.newNil(token.pos)
-	case itemVariable:
-		return t.useVar(token.pos, token.val)
-	case itemField:
-		return t.newField(token.pos, token.val)
-	case itemBool:
-		return t.newBool(token.pos, token.val == "true")
-	case itemCharConstant, itemComplex, itemNumber:
-		number, err := t.newNumber(token.pos, token.val, token.typ)
-		if err != nil {
-			t.error(err)
-		}
-		return number
-	case itemLeftParen:
-		return t.pipeline("parenthesized pipeline", itemRightParen)
-	case itemString, itemRawString:
-		s, err := strconv.Unquote(token.val)
-		if err != nil {
-			t.error(err)
-		}
-		return t.newString(token.pos, token.val, s)
-	}
-	t.backup()
-	return nil
-}
-
-// hasFunction reports if a function name exists in the Tree's maps.
-func (t *Tree) hasFunction(name string) bool {
-	for _, funcMap := range t.funcs {
-		if funcMap == nil {
-			continue
-		}
-		if funcMap[name] != nil {
-			return true
-		}
-	}
-	return false
-}
-
-// popVars trims the variable list to the specified length
-func (t *Tree) popVars(n int) {
-	t.vars = t.vars[:n]
-}
-
-// useVar returns a node for a variable reference. It errors if the
-// variable is not defined.
-func (t *Tree) useVar(pos Pos, name string) Node {
-	v := t.newVariable(pos, name)
-	for _, varName := range t.vars {
-		if varName == v.Ident[0] {
-			return v
-		}
-	}
-	t.errorf("undefined variable %q", v.Ident[0])
-	return nil
-}
diff --git a/contrib/go/_std_1.18/src/time/format.go b/contrib/go/_std_1.18/src/time/format.go
deleted file mode 100644
index 33e6543289..0000000000
--- a/contrib/go/_std_1.18/src/time/format.go
+++ /dev/null
@@ -1,1608 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package time
-
-import "errors"
-
-// These are predefined layouts for use in Time.Format and time.Parse.
-// The reference time used in these layouts is the specific time stamp:
-//	01/02 03:04:05PM '06 -0700
-// (January 2, 15:04:05, 2006, in time zone seven hours west of GMT).
-// That value is recorded as the constant named Layout, listed below. As a Unix
-// time, this is 1136239445. Since MST is GMT-0700, the reference would be
-// printed by the Unix date command as:
-//	Mon Jan 2 15:04:05 MST 2006
-// It is a regrettable historic error that the date uses the American convention
-// of putting the numerical month before the day.
-//
-// The example for Time.Format demonstrates the working of the layout string
-// in detail and is a good reference.
-//
-// Note that the RFC822, RFC850, and RFC1123 formats should be applied
-// only to local times. Applying them to UTC times will use "UTC" as the
-// time zone abbreviation, while strictly speaking those RFCs require the
-// use of "GMT" in that case.
-// In general RFC1123Z should be used instead of RFC1123 for servers
-// that insist on that format, and RFC3339 should be preferred for new protocols.
-// RFC3339, RFC822, RFC822Z, RFC1123, and RFC1123Z are useful for formatting;
-// when used with time.Parse they do not accept all the time formats
-// permitted by the RFCs and they do accept time formats not formally defined.
-// The RFC3339Nano format removes trailing zeros from the seconds field
-// and thus may not sort correctly once formatted.
-//
-// Most programs can use one of the defined constants as the layout passed to
-// Format or Parse. The rest of this comment can be ignored unless you are
-// creating a custom layout string.
-//
-// To define your own format, write down what the reference time would look like
-// formatted your way; see the values of constants like ANSIC, StampMicro or
-// Kitchen for examples. The model is to demonstrate what the reference time
-// looks like so that the Format and Parse methods can apply the same
-// transformation to a general time value.
-//
-// Here is a summary of the components of a layout string. Each element shows by
-// example the formatting of an element of the reference time. Only these values
-// are recognized. Text in the layout string that is not recognized as part of
-// the reference time is echoed verbatim during Format and expected to appear
-// verbatim in the input to Parse.
-//
-//	Year: "2006" "06"
-//	Month: "Jan" "January"
-//	Textual day of the week: "Mon" "Monday"
-//	Numeric day of the month: "2" "_2" "02"
-//	Numeric day of the year: "__2" "002"
-//	Hour: "15" "3" "03" (PM or AM)
-//	Minute: "4" "04"
-//	Second: "5" "05"
-//	AM/PM mark: "PM"
-//
-// Numeric time zone offsets format as follows:
-//	"-0700"  ±hhmm
-//	"-07:00" ±hh:mm
-//	"-07"    ±hh
-// Replacing the sign in the format with a Z triggers
-// the ISO 8601 behavior of printing Z instead of an
-// offset for the UTC zone. Thus:
-//	"Z0700"  Z or ±hhmm
-//	"Z07:00" Z or ±hh:mm
-//	"Z07"    Z or ±hh
-//
-// Within the format string, the underscores in "_2" and "__2" represent spaces
-// that may be replaced by digits if the following number has multiple digits,
-// for compatibility with fixed-width Unix time formats. A leading zero represents
-// a zero-padded value.
-//
-// The formats __2 and 002 are space-padded and zero-padded
-// three-character day of year; there is no unpadded day of year format.
-//
-// A comma or decimal point followed by one or more zeros represents
-// a fractional second, printed to the given number of decimal places.
-// A comma or decimal point followed by one or more nines represents
-// a fractional second, printed to the given number of decimal places, with
-// trailing zeros removed.
-// For example "15:04:05,000" or "15:04:05.000" formats or parses with
-// millisecond precision.
-//
-// Some valid layouts are invalid time values for time.Parse, due to formats
-// such as _ for space padding and Z for zone information.
-//
-const (
-	Layout      = "01/02 03:04:05PM '06 -0700" // The reference time, in numerical order.
-	ANSIC       = "Mon Jan _2 15:04:05 2006"
-	UnixDate    = "Mon Jan _2 15:04:05 MST 2006"
-	RubyDate    = "Mon Jan 02 15:04:05 -0700 2006"
-	RFC822      = "02 Jan 06 15:04 MST"
-	RFC822Z     = "02 Jan 06 15:04 -0700" // RFC822 with numeric zone
-	RFC850      = "Monday, 02-Jan-06 15:04:05 MST"
-	RFC1123     = "Mon, 02 Jan 2006 15:04:05 MST"
-	RFC1123Z    = "Mon, 02 Jan 2006 15:04:05 -0700" // RFC1123 with numeric zone
-	RFC3339     = "2006-01-02T15:04:05Z07:00"
-	RFC3339Nano = "2006-01-02T15:04:05.999999999Z07:00"
-	Kitchen     = "3:04PM"
-	// Handy time stamps.
-	Stamp      = "Jan _2 15:04:05"
-	StampMilli = "Jan _2 15:04:05.000"
-	StampMicro = "Jan _2 15:04:05.000000"
-	StampNano  = "Jan _2 15:04:05.000000000"
-)
-
-const (
-	_                        = iota
-	stdLongMonth             = iota + stdNeedDate  // "January"
-	stdMonth                                       // "Jan"
-	stdNumMonth                                    // "1"
-	stdZeroMonth                                   // "01"
-	stdLongWeekDay                                 // "Monday"
-	stdWeekDay                                     // "Mon"
-	stdDay                                         // "2"
-	stdUnderDay                                    // "_2"
-	stdZeroDay                                     // "02"
-	stdUnderYearDay                                // "__2"
-	stdZeroYearDay                                 // "002"
-	stdHour                  = iota + stdNeedClock // "15"
-	stdHour12                                      // "3"
-	stdZeroHour12                                  // "03"
-	stdMinute                                      // "4"
-	stdZeroMinute                                  // "04"
-	stdSecond                                      // "5"
-	stdZeroSecond                                  // "05"
-	stdLongYear              = iota + stdNeedDate  // "2006"
-	stdYear                                        // "06"
-	stdPM                    = iota + stdNeedClock // "PM"
-	stdpm                                          // "pm"
-	stdTZ                    = iota                // "MST"
-	stdISO8601TZ                                   // "Z0700"  // prints Z for UTC
-	stdISO8601SecondsTZ                            // "Z070000"
-	stdISO8601ShortTZ                              // "Z07"
-	stdISO8601ColonTZ                              // "Z07:00" // prints Z for UTC
-	stdISO8601ColonSecondsTZ                       // "Z07:00:00"
-	stdNumTZ                                       // "-0700"  // always numeric
-	stdNumSecondsTz                                // "-070000"
-	stdNumShortTZ                                  // "-07"    // always numeric
-	stdNumColonTZ                                  // "-07:00" // always numeric
-	stdNumColonSecondsTZ                           // "-07:00:00"
-	stdFracSecond0                                 // ".0", ".00", ... , trailing zeros included
-	stdFracSecond9                                 // ".9", ".99", ..., trailing zeros omitted
-
-	stdNeedDate       = 1 << 8             // need month, day, year
-	stdNeedClock      = 2 << 8             // need hour, minute, second
-	stdArgShift       = 16                 // extra argument in high bits, above low stdArgShift
-	stdSeparatorShift = 28                 // extra argument in high 4 bits for fractional second separators
-	stdMask           = 1<<stdArgShift - 1 // mask out argument
-)
-
-// std0x records the std values for "01", "02", ..., "06".
-var std0x = [...]int{stdZeroMonth, stdZeroDay, stdZeroHour12, stdZeroMinute, stdZeroSecond, stdYear}
-
-// startsWithLowerCase reports whether the string has a lower-case letter at the beginning.
-// Its purpose is to prevent matching strings like "Month" when looking for "Mon".
-func startsWithLowerCase(str string) bool {
-	if len(str) == 0 {
-		return false
-	}
-	c := str[0]
-	return 'a' <= c && c <= 'z'
-}
-
-// nextStdChunk finds the first occurrence of a std string in
-// layout and returns the text before, the std string, and the text after.
-func nextStdChunk(layout string) (prefix string, std int, suffix string) {
-	for i := 0; i < len(layout); i++ {
-		switch c := int(layout[i]); c {
-		case 'J': // January, Jan
-			if len(layout) >= i+3 && layout[i:i+3] == "Jan" {
-				if len(layout) >= i+7 && layout[i:i+7] == "January" {
-					return layout[0:i], stdLongMonth, layout[i+7:]
-				}
-				if !startsWithLowerCase(layout[i+3:]) {
-					return layout[0:i], stdMonth, layout[i+3:]
-				}
-			}
-
-		case 'M': // Monday, Mon, MST
-			if len(layout) >= i+3 {
-				if layout[i:i+3] == "Mon" {
-					if len(layout) >= i+6 && layout[i:i+6] == "Monday" {
-						return layout[0:i], stdLongWeekDay, layout[i+6:]
-					}
-					if !startsWithLowerCase(layout[i+3:]) {
-						return layout[0:i], stdWeekDay, layout[i+3:]
-					}
-				}
-				if layout[i:i+3] == "MST" {
-					return layout[0:i], stdTZ, layout[i+3:]
-				}
-			}
-
-		case '0': // 01, 02, 03, 04, 05, 06, 002
-			if len(layout) >= i+2 && '1' <= layout[i+1] && layout[i+1] <= '6' {
-				return layout[0:i], std0x[layout[i+1]-'1'], layout[i+2:]
-			}
-			if len(layout) >= i+3 && layout[i+1] == '0' && layout[i+2] == '2' {
-				return layout[0:i], stdZeroYearDay, layout[i+3:]
-			}
-
-		case '1': // 15, 1
-			if len(layout) >= i+2 && layout[i+1] == '5' {
-				return layout[0:i], stdHour, layout[i+2:]
-			}
-			return layout[0:i], stdNumMonth, layout[i+1:]
-
-		case '2': // 2006, 2
-			if len(layout) >= i+4 && layout[i:i+4] == "2006" {
-				return layout[0:i], stdLongYear, layout[i+4:]
-			}
-			return layout[0:i], stdDay, layout[i+1:]
-
-		case '_': // _2, _2006, __2
-			if len(layout) >= i+2 && layout[i+1] == '2' {
-				//_2006 is really a literal _, followed by stdLongYear
-				if len(layout) >= i+5 && layout[i+1:i+5] == "2006" {
-					return layout[0 : i+1], stdLongYear, layout[i+5:]
-				}
-				return layout[0:i], stdUnderDay, layout[i+2:]
-			}
-			if len(layout) >= i+3 && layout[i+1] == '_' && layout[i+2] == '2' {
-				return layout[0:i], stdUnderYearDay, layout[i+3:]
-			}
-
-		case '3':
-			return layout[0:i], stdHour12, layout[i+1:]
-
-		case '4':
-			return layout[0:i], stdMinute, layout[i+1:]
-
-		case '5':
-			return layout[0:i], stdSecond, layout[i+1:]
-
-		case 'P': // PM
-			if len(layout) >= i+2 && layout[i+1] == 'M' {
-				return layout[0:i], stdPM, layout[i+2:]
-			}
-
-		case 'p': // pm
-			if len(layout) >= i+2 && layout[i+1] == 'm' {
-				return layout[0:i], stdpm, layout[i+2:]
-			}
-
-		case '-': // -070000, -07:00:00, -0700, -07:00, -07
-			if len(layout) >= i+7 && layout[i:i+7] == "-070000" {
-				return layout[0:i], stdNumSecondsTz, layout[i+7:]
-			}
-			if len(layout) >= i+9 && layout[i:i+9] == "-07:00:00" {
-				return layout[0:i], stdNumColonSecondsTZ, layout[i+9:]
-			}
-			if len(layout) >= i+5 && layout[i:i+5] == "-0700" {
-				return layout[0:i], stdNumTZ, layout[i+5:]
-			}
-			if len(layout) >= i+6 && layout[i:i+6] == "-07:00" {
-				return layout[0:i], stdNumColonTZ, layout[i+6:]
-			}
-			if len(layout) >= i+3 && layout[i:i+3] == "-07" {
-				return layout[0:i], stdNumShortTZ, layout[i+3:]
-			}
-
-		case 'Z': // Z070000, Z07:00:00, Z0700, Z07:00,
-			if len(layout) >= i+7 && layout[i:i+7] == "Z070000" {
-				return layout[0:i], stdISO8601SecondsTZ, layout[i+7:]
-			}
-			if len(layout) >= i+9 && layout[i:i+9] == "Z07:00:00" {
-				return layout[0:i], stdISO8601ColonSecondsTZ, layout[i+9:]
-			}
-			if len(layout) >= i+5 && layout[i:i+5] == "Z0700" {
-				return layout[0:i], stdISO8601TZ, layout[i+5:]
-			}
-			if len(layout) >= i+6 && layout[i:i+6] == "Z07:00" {
-				return layout[0:i], stdISO8601ColonTZ, layout[i+6:]
-			}
-			if len(layout) >= i+3 && layout[i:i+3] == "Z07" {
-				return layout[0:i], stdISO8601ShortTZ, layout[i+3:]
-			}
-
-		case '.', ',': // ,000, or .000, or ,999, or .999 - repeated digits for fractional seconds.
-			if i+1 < len(layout) && (layout[i+1] == '0' || layout[i+1] == '9') {
-				ch := layout[i+1]
-				j := i + 1
-				for j < len(layout) && layout[j] == ch {
-					j++
-				}
-				// String of digits must end here - only fractional second is all digits.
-				if !isDigit(layout, j) {
-					code := stdFracSecond0
-					if layout[i+1] == '9' {
-						code = stdFracSecond9
-					}
-					std := stdFracSecond(code, j-(i+1), c)
-					return layout[0:i], std, layout[j:]
-				}
-			}
-		}
-	}
-	return layout, 0, ""
-}
-
-var longDayNames = []string{
-	"Sunday",
-	"Monday",
-	"Tuesday",
-	"Wednesday",
-	"Thursday",
-	"Friday",
-	"Saturday",
-}
-
-var shortDayNames = []string{
-	"Sun",
-	"Mon",
-	"Tue",
-	"Wed",
-	"Thu",
-	"Fri",
-	"Sat",
-}
-
-var shortMonthNames = []string{
-	"Jan",
-	"Feb",
-	"Mar",
-	"Apr",
-	"May",
-	"Jun",
-	"Jul",
-	"Aug",
-	"Sep",
-	"Oct",
-	"Nov",
-	"Dec",
-}
-
-var longMonthNames = []string{
-	"January",
-	"February",
-	"March",
-	"April",
-	"May",
-	"June",
-	"July",
-	"August",
-	"September",
-	"October",
-	"November",
-	"December",
-}
-
-// match reports whether s1 and s2 match ignoring case.
-// It is assumed s1 and s2 are the same length.
-func match(s1, s2 string) bool {
-	for i := 0; i < len(s1); i++ {
-		c1 := s1[i]
-		c2 := s2[i]
-		if c1 != c2 {
-			// Switch to lower-case; 'a'-'A' is known to be a single bit.
-			c1 |= 'a' - 'A'
-			c2 |= 'a' - 'A'
-			if c1 != c2 || c1 < 'a' || c1 > 'z' {
-				return false
-			}
-		}
-	}
-	return true
-}
-
-func lookup(tab []string, val string) (int, string, error) {
-	for i, v := range tab {
-		if len(val) >= len(v) && match(val[0:len(v)], v) {
-			return i, val[len(v):], nil
-		}
-	}
-	return -1, val, errBad
-}
-
-// appendInt appends the decimal form of x to b and returns the result.
-// If the decimal form (excluding sign) is shorter than width, the result is padded with leading 0's.
-// Duplicates functionality in strconv, but avoids dependency.
-func appendInt(b []byte, x int, width int) []byte {
-	u := uint(x)
-	if x < 0 {
-		b = append(b, '-')
-		u = uint(-x)
-	}
-
-	// Assemble decimal in reverse order.
-	var buf [20]byte
-	i := len(buf)
-	for u >= 10 {
-		i--
-		q := u / 10
-		buf[i] = byte('0' + u - q*10)
-		u = q
-	}
-	i--
-	buf[i] = byte('0' + u)
-
-	// Add 0-padding.
-	for w := len(buf) - i; w < width; w++ {
-		b = append(b, '0')
-	}
-
-	return append(b, buf[i:]...)
-}
-
-// Never printed, just needs to be non-nil for return by atoi.
-var atoiError = errors.New("time: invalid number")
-
-// Duplicates functionality in strconv, but avoids dependency.
-func atoi(s string) (x int, err error) {
-	neg := false
-	if s != "" && (s[0] == '-' || s[0] == '+') {
-		neg = s[0] == '-'
-		s = s[1:]
-	}
-	q, rem, err := leadingInt(s)
-	x = int(q)
-	if err != nil || rem != "" {
-		return 0, atoiError
-	}
-	if neg {
-		x = -x
-	}
-	return x, nil
-}
-
-// The "std" value passed to formatNano contains two packed fields: the number of
-// digits after the decimal and the separator character (period or comma).
-// These functions pack and unpack that variable.
-func stdFracSecond(code, n, c int) int {
-	// Use 0xfff to make the failure case even more absurd.
-	if c == '.' {
-		return code | ((n & 0xfff) << stdArgShift)
-	}
-	return code | ((n & 0xfff) << stdArgShift) | 1<<stdSeparatorShift
-}
-
-func digitsLen(std int) int {
-	return (std >> stdArgShift) & 0xfff
-}
-
-func separator(std int) byte {
-	if (std >> stdSeparatorShift) == 0 {
-		return '.'
-	}
-	return ','
-}
-
-// formatNano appends a fractional second, as nanoseconds, to b
-// and returns the result.
-func formatNano(b []byte, nanosec uint, std int) []byte {
-	var (
-		n         = digitsLen(std)
-		separator = separator(std)
-		trim      = std&stdMask == stdFracSecond9
-	)
-	u := nanosec
-	var buf [9]byte
-	for start := len(buf); start > 0; {
-		start--
-		buf[start] = byte(u%10 + '0')
-		u /= 10
-	}
-
-	if n > 9 {
-		n = 9
-	}
-	if trim {
-		for n > 0 && buf[n-1] == '0' {
-			n--
-		}
-		if n == 0 {
-			return b
-		}
-	}
-	b = append(b, separator)
-	return append(b, buf[:n]...)
-}
-
-// String returns the time formatted using the format string
-//	"2006-01-02 15:04:05.999999999 -0700 MST"
-//
-// If the time has a monotonic clock reading, the returned string
-// includes a final field "m=±<value>", where value is the monotonic
-// clock reading formatted as a decimal number of seconds.
-//
-// The returned string is meant for debugging; for a stable serialized
-// representation, use t.MarshalText, t.MarshalBinary, or t.Format
-// with an explicit format string.
-func (t Time) String() string {
-	s := t.Format("2006-01-02 15:04:05.999999999 -0700 MST")
-
-	// Format monotonic clock reading as m=±ddd.nnnnnnnnn.
-	if t.wall&hasMonotonic != 0 {
-		m2 := uint64(t.ext)
-		sign := byte('+')
-		if t.ext < 0 {
-			sign = '-'
-			m2 = -m2
-		}
-		m1, m2 := m2/1e9, m2%1e9
-		m0, m1 := m1/1e9, m1%1e9
-		buf := make([]byte, 0, 24)
-		buf = append(buf, " m="...)
-		buf = append(buf, sign)
-		wid := 0
-		if m0 != 0 {
-			buf = appendInt(buf, int(m0), 0)
-			wid = 9
-		}
-		buf = appendInt(buf, int(m1), wid)
-		buf = append(buf, '.')
-		buf = appendInt(buf, int(m2), 9)
-		s += string(buf)
-	}
-	return s
-}
-
-// GoString implements fmt.GoStringer and formats t to be printed in Go source
-// code.
-func (t Time) GoString() string {
-	buf := make([]byte, 0, 70)
-	buf = append(buf, "time.Date("...)
-	buf = appendInt(buf, t.Year(), 0)
-	month := t.Month()
-	if January <= month && month <= December {
-		buf = append(buf, ", time."...)
-		buf = append(buf, t.Month().String()...)
-	} else {
-		// It's difficult to construct a time.Time with a date outside the
-		// standard range but we might as well try to handle the case.
-		buf = appendInt(buf, int(month), 0)
-	}
-	buf = append(buf, ", "...)
-	buf = appendInt(buf, t.Day(), 0)
-	buf = append(buf, ", "...)
-	buf = appendInt(buf, t.Hour(), 0)
-	buf = append(buf, ", "...)
-	buf = appendInt(buf, t.Minute(), 0)
-	buf = append(buf, ", "...)
-	buf = appendInt(buf, t.Second(), 0)
-	buf = append(buf, ", "...)
-	buf = appendInt(buf, t.Nanosecond(), 0)
-	buf = append(buf, ", "...)
-	switch loc := t.Location(); loc {
-	case UTC, nil:
-		buf = append(buf, "time.UTC"...)
-	case Local:
-		buf = append(buf, "time.Local"...)
-	default:
-		// there are several options for how we could display this, none of
-		// which are great:
-		//
-		// - use Location(loc.name), which is not technically valid syntax
-		// - use LoadLocation(loc.name), which will cause a syntax error when
-		// embedded and also would require us to escape the string without
-		// importing fmt or strconv
-		// - try to use FixedZone, which would also require escaping the name
-		// and would represent e.g. "America/Los_Angeles" daylight saving time
-		// shifts inaccurately
-		// - use the pointer format, which is no worse than you'd get with the
-		// old fmt.Sprintf("%#v", t) format.
-		//
-		// Of these, Location(loc.name) is the least disruptive. This is an edge
-		// case we hope not to hit too often.
-		buf = append(buf, `time.Location(`...)
-		buf = append(buf, []byte(quote(loc.name))...)
-		buf = append(buf, `)`...)
-	}
-	buf = append(buf, ')')
-	return string(buf)
-}
-
-// Format returns a textual representation of the time value formatted according
-// to the layout defined by the argument. See the documentation for the
-// constant called Layout to see how to represent the layout format.
-//
-// The executable example for Time.Format demonstrates the working
-// of the layout string in detail and is a good reference.
-func (t Time) Format(layout string) string {
-	const bufSize = 64
-	var b []byte
-	max := len(layout) + 10
-	if max < bufSize {
-		var buf [bufSize]byte
-		b = buf[:0]
-	} else {
-		b = make([]byte, 0, max)
-	}
-	b = t.AppendFormat(b, layout)
-	return string(b)
-}
-
-// AppendFormat is like Format but appends the textual
-// representation to b and returns the extended buffer.
-func (t Time) AppendFormat(b []byte, layout string) []byte {
-	var (
-		name, offset, abs = t.locabs()
-
-		year  int = -1
-		month Month
-		day   int
-		yday  int
-		hour  int = -1
-		min   int
-		sec   int
-	)
-	// Each iteration generates one std value.
-	for layout != "" {
-		prefix, std, suffix := nextStdChunk(layout)
-		if prefix != "" {
-			b = append(b, prefix...)
-		}
-		if std == 0 {
-			break
-		}
-		layout = suffix
-
-		// Compute year, month, day if needed.
-		if year < 0 && std&stdNeedDate != 0 {
-			year, month, day, yday = absDate(abs, true)
-			yday++
-		}
-
-		// Compute hour, minute, second if needed.
-		if hour < 0 && std&stdNeedClock != 0 {
-			hour, min, sec = absClock(abs)
-		}
-
-		switch std & stdMask {
-		case stdYear:
-			y := year
-			if y < 0 {
-				y = -y
-			}
-			b = appendInt(b, y%100, 2)
-		case stdLongYear:
-			b = appendInt(b, year, 4)
-		case stdMonth:
-			b = append(b, month.String()[:3]...)
-		case stdLongMonth:
-			m := month.String()
-			b = append(b, m...)
-		case stdNumMonth:
-			b = appendInt(b, int(month), 0)
-		case stdZeroMonth:
-			b = appendInt(b, int(month), 2)
-		case stdWeekDay:
-			b = append(b, absWeekday(abs).String()[:3]...)
-		case stdLongWeekDay:
-			s := absWeekday(abs).String()
-			b = append(b, s...)
-		case stdDay:
-			b = appendInt(b, day, 0)
-		case stdUnderDay:
-			if day < 10 {
-				b = append(b, ' ')
-			}
-			b = appendInt(b, day, 0)
-		case stdZeroDay:
-			b = appendInt(b, day, 2)
-		case stdUnderYearDay:
-			if yday < 100 {
-				b = append(b, ' ')
-				if yday < 10 {
-					b = append(b, ' ')
-				}
-			}
-			b = appendInt(b, yday, 0)
-		case stdZeroYearDay:
-			b = appendInt(b, yday, 3)
-		case stdHour:
-			b = appendInt(b, hour, 2)
-		case stdHour12:
-			// Noon is 12PM, midnight is 12AM.
-			hr := hour % 12
-			if hr == 0 {
-				hr = 12
-			}
-			b = appendInt(b, hr, 0)
-		case stdZeroHour12:
-			// Noon is 12PM, midnight is 12AM.
-			hr := hour % 12
-			if hr == 0 {
-				hr = 12
-			}
-			b = appendInt(b, hr, 2)
-		case stdMinute:
-			b = appendInt(b, min, 0)
-		case stdZeroMinute:
-			b = appendInt(b, min, 2)
-		case stdSecond:
-			b = appendInt(b, sec, 0)
-		case stdZeroSecond:
-			b = appendInt(b, sec, 2)
-		case stdPM:
-			if hour >= 12 {
-				b = append(b, "PM"...)
-			} else {
-				b = append(b, "AM"...)
-			}
-		case stdpm:
-			if hour >= 12 {
-				b = append(b, "pm"...)
-			} else {
-				b = append(b, "am"...)
-			}
-		case stdISO8601TZ, stdISO8601ColonTZ, stdISO8601SecondsTZ, stdISO8601ShortTZ, stdISO8601ColonSecondsTZ, stdNumTZ, stdNumColonTZ, stdNumSecondsTz, stdNumShortTZ, stdNumColonSecondsTZ:
-			// Ugly special case. We cheat and take the "Z" variants
-			// to mean "the time zone as formatted for ISO 8601".
-			if offset == 0 && (std == stdISO8601TZ || std == stdISO8601ColonTZ || std == stdISO8601SecondsTZ || std == stdISO8601ShortTZ || std == stdISO8601ColonSecondsTZ) {
-				b = append(b, 'Z')
-				break
-			}
-			zone := offset / 60 // convert to minutes
-			absoffset := offset
-			if zone < 0 {
-				b = append(b, '-')
-				zone = -zone
-				absoffset = -absoffset
-			} else {
-				b = append(b, '+')
-			}
-			b = appendInt(b, zone/60, 2)
-			if std == stdISO8601ColonTZ || std == stdNumColonTZ || std == stdISO8601ColonSecondsTZ || std == stdNumColonSecondsTZ {
-				b = append(b, ':')
-			}
-			if std != stdNumShortTZ && std != stdISO8601ShortTZ {
-				b = appendInt(b, zone%60, 2)
-			}
-
-			// append seconds if appropriate
-			if std == stdISO8601SecondsTZ || std == stdNumSecondsTz || std == stdNumColonSecondsTZ || std == stdISO8601ColonSecondsTZ {
-				if std == stdNumColonSecondsTZ || std == stdISO8601ColonSecondsTZ {
-					b = append(b, ':')
-				}
-				b = appendInt(b, absoffset%60, 2)
-			}
-
-		case stdTZ:
-			if name != "" {
-				b = append(b, name...)
-				break
-			}
-			// No time zone known for this time, but we must print one.
-			// Use the -0700 format.
-			zone := offset / 60 // convert to minutes
-			if zone < 0 {
-				b = append(b, '-')
-				zone = -zone
-			} else {
-				b = append(b, '+')
-			}
-			b = appendInt(b, zone/60, 2)
-			b = appendInt(b, zone%60, 2)
-		case stdFracSecond0, stdFracSecond9:
-			b = formatNano(b, uint(t.Nanosecond()), std)
-		}
-	}
-	return b
-}
-
-var errBad = errors.New("bad value for field") // placeholder not passed to user
-
-// ParseError describes a problem parsing a time string.
-type ParseError struct {
-	Layout     string
-	Value      string
-	LayoutElem string
-	ValueElem  string
-	Message    string
-}
-
-// These are borrowed from unicode/utf8 and strconv and replicate behavior in
-// that package, since we can't take a dependency on either.
-const (
-	lowerhex  = "0123456789abcdef"
-	runeSelf  = 0x80
-	runeError = '\uFFFD'
-)
-
-func quote(s string) string {
-	buf := make([]byte, 1, len(s)+2) // slice will be at least len(s) + quotes
-	buf[0] = '"'
-	for i, c := range s {
-		if c >= runeSelf || c < ' ' {
-			// This means you are asking us to parse a time.Duration or
-			// time.Location with unprintable or non-ASCII characters in it.
-			// We don't expect to hit this case very often. We could try to
-			// reproduce strconv.Quote's behavior with full fidelity but
-			// given how rarely we expect to hit these edge cases, speed and
-			// conciseness are better.
-			var width int
-			if c == runeError {
-				width = 1
-				if i+2 < len(s) && s[i:i+3] == string(runeError) {
-					width = 3
-				}
-			} else {
-				width = len(string(c))
-			}
-			for j := 0; j < width; j++ {
-				buf = append(buf, `\x`...)
-				buf = append(buf, lowerhex[s[i+j]>>4])
-				buf = append(buf, lowerhex[s[i+j]&0xF])
-			}
-		} else {
-			if c == '"' || c == '\\' {
-				buf = append(buf, '\\')
-			}
-			buf = append(buf, string(c)...)
-		}
-	}
-	buf = append(buf, '"')
-	return string(buf)
-}
-
-// Error returns the string representation of a ParseError.
-func (e *ParseError) Error() string {
-	if e.Message == "" {
-		return "parsing time " +
-			quote(e.Value) + " as " +
-			quote(e.Layout) + ": cannot parse " +
-			quote(e.ValueElem) + " as " +
-			quote(e.LayoutElem)
-	}
-	return "parsing time " +
-		quote(e.Value) + e.Message
-}
-
-// isDigit reports whether s[i] is in range and is a decimal digit.
-func isDigit(s string, i int) bool {
-	if len(s) <= i {
-		return false
-	}
-	c := s[i]
-	return '0' <= c && c <= '9'
-}
-
-// getnum parses s[0:1] or s[0:2] (fixed forces s[0:2])
-// as a decimal integer and returns the integer and the
-// remainder of the string.
-func getnum(s string, fixed bool) (int, string, error) {
-	if !isDigit(s, 0) {
-		return 0, s, errBad
-	}
-	if !isDigit(s, 1) {
-		if fixed {
-			return 0, s, errBad
-		}
-		return int(s[0] - '0'), s[1:], nil
-	}
-	return int(s[0]-'0')*10 + int(s[1]-'0'), s[2:], nil
-}
-
-// getnum3 parses s[0:1], s[0:2], or s[0:3] (fixed forces s[0:3])
-// as a decimal integer and returns the integer and the remainder
-// of the string.
-func getnum3(s string, fixed bool) (int, string, error) {
-	var n, i int
-	for i = 0; i < 3 && isDigit(s, i); i++ {
-		n = n*10 + int(s[i]-'0')
-	}
-	if i == 0 || fixed && i != 3 {
-		return 0, s, errBad
-	}
-	return n, s[i:], nil
-}
-
-func cutspace(s string) string {
-	for len(s) > 0 && s[0] == ' ' {
-		s = s[1:]
-	}
-	return s
-}
-
-// skip removes the given prefix from value,
-// treating runs of space characters as equivalent.
-func skip(value, prefix string) (string, error) {
-	for len(prefix) > 0 {
-		if prefix[0] == ' ' {
-			if len(value) > 0 && value[0] != ' ' {
-				return value, errBad
-			}
-			prefix = cutspace(prefix)
-			value = cutspace(value)
-			continue
-		}
-		if len(value) == 0 || value[0] != prefix[0] {
-			return value, errBad
-		}
-		prefix = prefix[1:]
-		value = value[1:]
-	}
-	return value, nil
-}
-
-// Parse parses a formatted string and returns the time value it represents.
-// See the documentation for the constant called Layout to see how to
-// represent the format. The second argument must be parseable using
-// the format string (layout) provided as the first argument.
-//
-// The example for Time.Format demonstrates the working of the layout string
-// in detail and is a good reference.
-//
-// When parsing (only), the input may contain a fractional second
-// field immediately after the seconds field, even if the layout does not
-// signify its presence. In that case either a comma or a decimal point
-// followed by a maximal series of digits is parsed as a fractional second.
-// Fractional seconds are truncated to nanosecond precision.
-//
-// Elements omitted from the layout are assumed to be zero or, when
-// zero is impossible, one, so parsing "3:04pm" returns the time
-// corresponding to Jan 1, year 0, 15:04:00 UTC (note that because the year is
-// 0, this time is before the zero Time).
-// Years must be in the range 0000..9999. The day of the week is checked
-// for syntax but it is otherwise ignored.
-//
-// For layouts specifying the two-digit year 06, a value NN >= 69 will be treated
-// as 19NN and a value NN < 69 will be treated as 20NN.
-//
-// The remainder of this comment describes the handling of time zones.
-//
-// In the absence of a time zone indicator, Parse returns a time in UTC.
-//
-// When parsing a time with a zone offset like -0700, if the offset corresponds
-// to a time zone used by the current location (Local), then Parse uses that
-// location and zone in the returned time. Otherwise it records the time as
-// being in a fabricated location with time fixed at the given zone offset.
-//
-// When parsing a time with a zone abbreviation like MST, if the zone abbreviation
-// has a defined offset in the current location, then that offset is used.
-// The zone abbreviation "UTC" is recognized as UTC regardless of location.
-// If the zone abbreviation is unknown, Parse records the time as being
-// in a fabricated location with the given zone abbreviation and a zero offset.
-// This choice means that such a time can be parsed and reformatted with the
-// same layout losslessly, but the exact instant used in the representation will
-// differ by the actual zone offset. To avoid such problems, prefer time layouts
-// that use a numeric zone offset, or use ParseInLocation.
-func Parse(layout, value string) (Time, error) {
-	return parse(layout, value, UTC, Local)
-}
-
-// ParseInLocation is like Parse but differs in two important ways.
-// First, in the absence of time zone information, Parse interprets a time as UTC;
-// ParseInLocation interprets the time as in the given location.
-// Second, when given a zone offset or abbreviation, Parse tries to match it
-// against the Local location; ParseInLocation uses the given location.
-func ParseInLocation(layout, value string, loc *Location) (Time, error) {
-	return parse(layout, value, loc, loc)
-}
-
-func parse(layout, value string, defaultLocation, local *Location) (Time, error) {
-	alayout, avalue := layout, value
-	rangeErrString := "" // set if a value is out of range
-	amSet := false       // do we need to subtract 12 from the hour for midnight?
-	pmSet := false       // do we need to add 12 to the hour?
-
-	// Time being constructed.
-	var (
-		year       int
-		month      int = -1
-		day        int = -1
-		yday       int = -1
-		hour       int
-		min        int
-		sec        int
-		nsec       int
-		z          *Location
-		zoneOffset int = -1
-		zoneName   string
-	)
-
-	// Each iteration processes one std value.
-	for {
-		var err error
-		prefix, std, suffix := nextStdChunk(layout)
-		stdstr := layout[len(prefix) : len(layout)-len(suffix)]
-		value, err = skip(value, prefix)
-		if err != nil {
-			return Time{}, &ParseError{alayout, avalue, prefix, value, ""}
-		}
-		if std == 0 {
-			if len(value) != 0 {
-				return Time{}, &ParseError{alayout, avalue, "", value, ": extra text: " + quote(value)}
-			}
-			break
-		}
-		layout = suffix
-		var p string
-		switch std & stdMask {
-		case stdYear:
-			if len(value) < 2 {
-				err = errBad
-				break
-			}
-			hold := value
-			p, value = value[0:2], value[2:]
-			year, err = atoi(p)
-			if err != nil {
-				value = hold
-			} else if year >= 69 { // Unix time starts Dec 31 1969 in some time zones
-				year += 1900
-			} else {
-				year += 2000
-			}
-		case stdLongYear:
-			if len(value) < 4 || !isDigit(value, 0) {
-				err = errBad
-				break
-			}
-			p, value = value[0:4], value[4:]
-			year, err = atoi(p)
-		case stdMonth:
-			month, value, err = lookup(shortMonthNames, value)
-			month++
-		case stdLongMonth:
-			month, value, err = lookup(longMonthNames, value)
-			month++
-		case stdNumMonth, stdZeroMonth:
-			month, value, err = getnum(value, std == stdZeroMonth)
-			if err == nil && (month <= 0 || 12 < month) {
-				rangeErrString = "month"
-			}
-		case stdWeekDay:
-			// Ignore weekday except for error checking.
-			_, value, err = lookup(shortDayNames, value)
-		case stdLongWeekDay:
-			_, value, err = lookup(longDayNames, value)
-		case stdDay, stdUnderDay, stdZeroDay:
-			if std == stdUnderDay && len(value) > 0 && value[0] == ' ' {
-				value = value[1:]
-			}
-			day, value, err = getnum(value, std == stdZeroDay)
-			// Note that we allow any one- or two-digit day here.
-			// The month, day, year combination is validated after we've completed parsing.
-		case stdUnderYearDay, stdZeroYearDay:
-			for i := 0; i < 2; i++ {
-				if std == stdUnderYearDay && len(value) > 0 && value[0] == ' ' {
-					value = value[1:]
-				}
-			}
-			yday, value, err = getnum3(value, std == stdZeroYearDay)
-			// Note that we allow any one-, two-, or three-digit year-day here.
-			// The year-day, year combination is validated after we've completed parsing.
-		case stdHour:
-			hour, value, err = getnum(value, false)
-			if hour < 0 || 24 <= hour {
-				rangeErrString = "hour"
-			}
-		case stdHour12, stdZeroHour12:
-			hour, value, err = getnum(value, std == stdZeroHour12)
-			if hour < 0 || 12 < hour {
-				rangeErrString = "hour"
-			}
-		case stdMinute, stdZeroMinute:
-			min, value, err = getnum(value, std == stdZeroMinute)
-			if min < 0 || 60 <= min {
-				rangeErrString = "minute"
-			}
-		case stdSecond, stdZeroSecond:
-			sec, value, err = getnum(value, std == stdZeroSecond)
-			if sec < 0 || 60 <= sec {
-				rangeErrString = "second"
-				break
-			}
-			// Special case: do we have a fractional second but no
-			// fractional second in the format?
-			if len(value) >= 2 && commaOrPeriod(value[0]) && isDigit(value, 1) {
-				_, std, _ = nextStdChunk(layout)
-				std &= stdMask
-				if std == stdFracSecond0 || std == stdFracSecond9 {
-					// Fractional second in the layout; proceed normally
-					break
-				}
-				// No fractional second in the layout but we have one in the input.
-				n := 2
-				for ; n < len(value) && isDigit(value, n); n++ {
-				}
-				nsec, rangeErrString, err = parseNanoseconds(value, n)
-				value = value[n:]
-			}
-		case stdPM:
-			if len(value) < 2 {
-				err = errBad
-				break
-			}
-			p, value = value[0:2], value[2:]
-			switch p {
-			case "PM":
-				pmSet = true
-			case "AM":
-				amSet = true
-			default:
-				err = errBad
-			}
-		case stdpm:
-			if len(value) < 2 {
-				err = errBad
-				break
-			}
-			p, value = value[0:2], value[2:]
-			switch p {
-			case "pm":
-				pmSet = true
-			case "am":
-				amSet = true
-			default:
-				err = errBad
-			}
-		case stdISO8601TZ, stdISO8601ColonTZ, stdISO8601SecondsTZ, stdISO8601ShortTZ, stdISO8601ColonSecondsTZ, stdNumTZ, stdNumShortTZ, stdNumColonTZ, stdNumSecondsTz, stdNumColonSecondsTZ:
-			if (std == stdISO8601TZ || std == stdISO8601ShortTZ || std == stdISO8601ColonTZ) && len(value) >= 1 && value[0] == 'Z' {
-				value = value[1:]
-				z = UTC
-				break
-			}
-			var sign, hour, min, seconds string
-			if std == stdISO8601ColonTZ || std == stdNumColonTZ {
-				if len(value) < 6 {
-					err = errBad
-					break
-				}
-				if value[3] != ':' {
-					err = errBad
-					break
-				}
-				sign, hour, min, seconds, value = value[0:1], value[1:3], value[4:6], "00", value[6:]
-			} else if std == stdNumShortTZ || std == stdISO8601ShortTZ {
-				if len(value) < 3 {
-					err = errBad
-					break
-				}
-				sign, hour, min, seconds, value = value[0:1], value[1:3], "00", "00", value[3:]
-			} else if std == stdISO8601ColonSecondsTZ || std == stdNumColonSecondsTZ {
-				if len(value) < 9 {
-					err = errBad
-					break
-				}
-				if value[3] != ':' || value[6] != ':' {
-					err = errBad
-					break
-				}
-				sign, hour, min, seconds, value = value[0:1], value[1:3], value[4:6], value[7:9], value[9:]
-			} else if std == stdISO8601SecondsTZ || std == stdNumSecondsTz {
-				if len(value) < 7 {
-					err = errBad
-					break
-				}
-				sign, hour, min, seconds, value = value[0:1], value[1:3], value[3:5], value[5:7], value[7:]
-			} else {
-				if len(value) < 5 {
-					err = errBad
-					break
-				}
-				sign, hour, min, seconds, value = value[0:1], value[1:3], value[3:5], "00", value[5:]
-			}
-			var hr, mm, ss int
-			hr, err = atoi(hour)
-			if err == nil {
-				mm, err = atoi(min)
-			}
-			if err == nil {
-				ss, err = atoi(seconds)
-			}
-			zoneOffset = (hr*60+mm)*60 + ss // offset is in seconds
-			switch sign[0] {
-			case '+':
-			case '-':
-				zoneOffset = -zoneOffset
-			default:
-				err = errBad
-			}
-		case stdTZ:
-			// Does it look like a time zone?
-			if len(value) >= 3 && value[0:3] == "UTC" {
-				z = UTC
-				value = value[3:]
-				break
-			}
-			n, ok := parseTimeZone(value)
-			if !ok {
-				err = errBad
-				break
-			}
-			zoneName, value = value[:n], value[n:]
-
-		case stdFracSecond0:
-			// stdFracSecond0 requires the exact number of digits as specified in
-			// the layout.
-			ndigit := 1 + digitsLen(std)
-			if len(value) < ndigit {
-				err = errBad
-				break
-			}
-			nsec, rangeErrString, err = parseNanoseconds(value, ndigit)
-			value = value[ndigit:]
-
-		case stdFracSecond9:
-			if len(value) < 2 || !commaOrPeriod(value[0]) || value[1] < '0' || '9' < value[1] {
-				// Fractional second omitted.
-				break
-			}
-			// Take any number of digits, even more than asked for,
-			// because it is what the stdSecond case would do.
-			i := 0
-			for i < 9 && i+1 < len(value) && '0' <= value[i+1] && value[i+1] <= '9' {
-				i++
-			}
-			nsec, rangeErrString, err = parseNanoseconds(value, 1+i)
-			value = value[1+i:]
-		}
-		if rangeErrString != "" {
-			return Time{}, &ParseError{alayout, avalue, stdstr, value, ": " + rangeErrString + " out of range"}
-		}
-		if err != nil {
-			return Time{}, &ParseError{alayout, avalue, stdstr, value, ""}
-		}
-	}
-	if pmSet && hour < 12 {
-		hour += 12
-	} else if amSet && hour == 12 {
-		hour = 0
-	}
-
-	// Convert yday to day, month.
-	if yday >= 0 {
-		var d int
-		var m int
-		if isLeap(year) {
-			if yday == 31+29 {
-				m = int(February)
-				d = 29
-			} else if yday > 31+29 {
-				yday--
-			}
-		}
-		if yday < 1 || yday > 365 {
-			return Time{}, &ParseError{alayout, avalue, "", value, ": day-of-year out of range"}
-		}
-		if m == 0 {
-			m = (yday-1)/31 + 1
-			if int(daysBefore[m]) < yday {
-				m++
-			}
-			d = yday - int(daysBefore[m-1])
-		}
-		// If month, day already seen, yday's m, d must match.
-		// Otherwise, set them from m, d.
-		if month >= 0 && month != m {
-			return Time{}, &ParseError{alayout, avalue, "", value, ": day-of-year does not match month"}
-		}
-		month = m
-		if day >= 0 && day != d {
-			return Time{}, &ParseError{alayout, avalue, "", value, ": day-of-year does not match day"}
-		}
-		day = d
-	} else {
-		if month < 0 {
-			month = int(January)
-		}
-		if day < 0 {
-			day = 1
-		}
-	}
-
-	// Validate the day of the month.
-	if day < 1 || day > daysIn(Month(month), year) {
-		return Time{}, &ParseError{alayout, avalue, "", value, ": day out of range"}
-	}
-
-	if z != nil {
-		return Date(year, Month(month), day, hour, min, sec, nsec, z), nil
-	}
-
-	if zoneOffset != -1 {
-		t := Date(year, Month(month), day, hour, min, sec, nsec, UTC)
-		t.addSec(-int64(zoneOffset))
-
-		// Look for local zone with the given offset.
-		// If that zone was in effect at the given time, use it.
-		name, offset, _, _, _ := local.lookup(t.unixSec())
-		if offset == zoneOffset && (zoneName == "" || name == zoneName) {
-			t.setLoc(local)
-			return t, nil
-		}
-
-		// Otherwise create fake zone to record offset.
-		t.setLoc(FixedZone(zoneName, zoneOffset))
-		return t, nil
-	}
-
-	if zoneName != "" {
-		t := Date(year, Month(month), day, hour, min, sec, nsec, UTC)
-		// Look for local zone with the given offset.
-		// If that zone was in effect at the given time, use it.
-		offset, ok := local.lookupName(zoneName, t.unixSec())
-		if ok {
-			t.addSec(-int64(offset))
-			t.setLoc(local)
-			return t, nil
-		}
-
-		// Otherwise, create fake zone with unknown offset.
-		if len(zoneName) > 3 && zoneName[:3] == "GMT" {
-			offset, _ = atoi(zoneName[3:]) // Guaranteed OK by parseGMT.
-			offset *= 3600
-		}
-		t.setLoc(FixedZone(zoneName, offset))
-		return t, nil
-	}
-
-	// Otherwise, fall back to default.
-	return Date(year, Month(month), day, hour, min, sec, nsec, defaultLocation), nil
-}
-
-// parseTimeZone parses a time zone string and returns its length. Time zones
-// are human-generated and unpredictable. We can't do precise error checking.
-// On the other hand, for a correct parse there must be a time zone at the
-// beginning of the string, so it's almost always true that there's one
-// there. We look at the beginning of the string for a run of upper-case letters.
-// If there are more than 5, it's an error.
-// If there are 4 or 5 and the last is a T, it's a time zone.
-// If there are 3, it's a time zone.
-// Otherwise, other than special cases, it's not a time zone.
-// GMT is special because it can have an hour offset.
-func parseTimeZone(value string) (length int, ok bool) {
-	if len(value) < 3 {
-		return 0, false
-	}
-	// Special case 1: ChST and MeST are the only zones with a lower-case letter.
-	if len(value) >= 4 && (value[:4] == "ChST" || value[:4] == "MeST") {
-		return 4, true
-	}
-	// Special case 2: GMT may have an hour offset; treat it specially.
-	if value[:3] == "GMT" {
-		length = parseGMT(value)
-		return length, true
-	}
-	// Special Case 3: Some time zones are not named, but have +/-00 format
-	if value[0] == '+' || value[0] == '-' {
-		length = parseSignedOffset(value)
-		ok := length > 0 // parseSignedOffset returns 0 in case of bad input
-		return length, ok
-	}
-	// How many upper-case letters are there? Need at least three, at most five.
-	var nUpper int
-	for nUpper = 0; nUpper < 6; nUpper++ {
-		if nUpper >= len(value) {
-			break
-		}
-		if c := value[nUpper]; c < 'A' || 'Z' < c {
-			break
-		}
-	}
-	switch nUpper {
-	case 0, 1, 2, 6:
-		return 0, false
-	case 5: // Must end in T to match.
-		if value[4] == 'T' {
-			return 5, true
-		}
-	case 4:
-		// Must end in T, except one special case.
-		if value[3] == 'T' || value[:4] == "WITA" {
-			return 4, true
-		}
-	case 3:
-		return 3, true
-	}
-	return 0, false
-}
-
-// parseGMT parses a GMT time zone. The input string is known to start "GMT".
-// The function checks whether that is followed by a sign and a number in the
-// range -23 through +23 excluding zero.
-func parseGMT(value string) int {
-	value = value[3:]
-	if len(value) == 0 {
-		return 3
-	}
-
-	return 3 + parseSignedOffset(value)
-}
-
-// parseSignedOffset parses a signed timezone offset (e.g. "+03" or "-04").
-// The function checks for a signed number in the range -23 through +23 excluding zero.
-// Returns length of the found offset string or 0 otherwise
-func parseSignedOffset(value string) int {
-	sign := value[0]
-	if sign != '-' && sign != '+' {
-		return 0
-	}
-	x, rem, err := leadingInt(value[1:])
-
-	// fail if nothing consumed by leadingInt
-	if err != nil || value[1:] == rem {
-		return 0
-	}
-	if x > 23 {
-		return 0
-	}
-	return len(value) - len(rem)
-}
-
-func commaOrPeriod(b byte) bool {
-	return b == '.' || b == ','
-}
-
-func parseNanoseconds(value string, nbytes int) (ns int, rangeErrString string, err error) {
-	if !commaOrPeriod(value[0]) {
-		err = errBad
-		return
-	}
-	if nbytes > 10 {
-		value = value[:10]
-		nbytes = 10
-	}
-	if ns, err = atoi(value[1:nbytes]); err != nil {
-		return
-	}
-	if ns < 0 {
-		rangeErrString = "fractional second"
-		return
-	}
-	// We need nanoseconds, which means scaling by the number
-	// of missing digits in the format, maximum length 10.
-	scaleDigits := 10 - nbytes
-	for i := 0; i < scaleDigits; i++ {
-		ns *= 10
-	}
-	return
-}
-
-var errLeadingInt = errors.New("time: bad [0-9]*") // never printed
-
-// leadingInt consumes the leading [0-9]* from s.
-func leadingInt(s string) (x uint64, rem string, err error) {
-	i := 0
-	for ; i < len(s); i++ {
-		c := s[i]
-		if c < '0' || c > '9' {
-			break
-		}
-		if x > 1<<63/10 {
-			// overflow
-			return 0, "", errLeadingInt
-		}
-		x = x*10 + uint64(c) - '0'
-		if x > 1<<63 {
-			// overflow
-			return 0, "", errLeadingInt
-		}
-	}
-	return x, s[i:], nil
-}
-
-// leadingFraction consumes the leading [0-9]* from s.
-// It is used only for fractions, so does not return an error on overflow,
-// it just stops accumulating precision.
-func leadingFraction(s string) (x uint64, scale float64, rem string) {
-	i := 0
-	scale = 1
-	overflow := false
-	for ; i < len(s); i++ {
-		c := s[i]
-		if c < '0' || c > '9' {
-			break
-		}
-		if overflow {
-			continue
-		}
-		if x > (1<<63-1)/10 {
-			// It's possible for overflow to give a positive number, so take care.
-			overflow = true
-			continue
-		}
-		y := x*10 + uint64(c) - '0'
-		if y > 1<<63 {
-			overflow = true
-			continue
-		}
-		x = y
-		scale *= 10
-	}
-	return x, scale, s[i:]
-}
-
-var unitMap = map[string]uint64{
-	"ns": uint64(Nanosecond),
-	"us": uint64(Microsecond),
-	"µs": uint64(Microsecond), // U+00B5 = micro symbol
-	"μs": uint64(Microsecond), // U+03BC = Greek letter mu
-	"ms": uint64(Millisecond),
-	"s":  uint64(Second),
-	"m":  uint64(Minute),
-	"h":  uint64(Hour),
-}
-
-// ParseDuration parses a duration string.
-// A duration string is a possibly signed sequence of
-// decimal numbers, each with optional fraction and a unit suffix,
-// such as "300ms", "-1.5h" or "2h45m".
-// Valid time units are "ns", "us" (or "µs"), "ms", "s", "m", "h".
-func ParseDuration(s string) (Duration, error) {
-	// [-+]?([0-9]*(\.[0-9]*)?[a-z]+)+
-	orig := s
-	var d uint64
-	neg := false
-
-	// Consume [-+]?
-	if s != "" {
-		c := s[0]
-		if c == '-' || c == '+' {
-			neg = c == '-'
-			s = s[1:]
-		}
-	}
-	// Special case: if all that is left is "0", this is zero.
-	if s == "0" {
-		return 0, nil
-	}
-	if s == "" {
-		return 0, errors.New("time: invalid duration " + quote(orig))
-	}
-	for s != "" {
-		var (
-			v, f  uint64      // integers before, after decimal point
-			scale float64 = 1 // value = v + f/scale
-		)
-
-		var err error
-
-		// The next character must be [0-9.]
-		if !(s[0] == '.' || '0' <= s[0] && s[0] <= '9') {
-			return 0, errors.New("time: invalid duration " + quote(orig))
-		}
-		// Consume [0-9]*
-		pl := len(s)
-		v, s, err = leadingInt(s)
-		if err != nil {
-			return 0, errors.New("time: invalid duration " + quote(orig))
-		}
-		pre := pl != len(s) // whether we consumed anything before a period
-
-		// Consume (\.[0-9]*)?
-		post := false
-		if s != "" && s[0] == '.' {
-			s = s[1:]
-			pl := len(s)
-			f, scale, s = leadingFraction(s)
-			post = pl != len(s)
-		}
-		if !pre && !post {
-			// no digits (e.g. ".s" or "-.s")
-			return 0, errors.New("time: invalid duration " + quote(orig))
-		}
-
-		// Consume unit.
-		i := 0
-		for ; i < len(s); i++ {
-			c := s[i]
-			if c == '.' || '0' <= c && c <= '9' {
-				break
-			}
-		}
-		if i == 0 {
-			return 0, errors.New("time: missing unit in duration " + quote(orig))
-		}
-		u := s[:i]
-		s = s[i:]
-		unit, ok := unitMap[u]
-		if !ok {
-			return 0, errors.New("time: unknown unit " + quote(u) + " in duration " + quote(orig))
-		}
-		if v > 1<<63/unit {
-			// overflow
-			return 0, errors.New("time: invalid duration " + quote(orig))
-		}
-		v *= unit
-		if f > 0 {
-			// float64 is needed to be nanosecond accurate for fractions of hours.
-			// v >= 0 && (f*unit/scale) <= 3.6e+12 (ns/h, h is the largest unit)
-			v += uint64(float64(f) * (float64(unit) / scale))
-			if v > 1<<63 {
-				// overflow
-				return 0, errors.New("time: invalid duration " + quote(orig))
-			}
-		}
-		d += v
-		if d > 1<<63 {
-			return 0, errors.New("time: invalid duration " + quote(orig))
-		}
-	}
-	if neg {
-		return -Duration(d), nil
-	}
-	if d > 1<<63-1 {
-		return 0, errors.New("time: invalid duration " + quote(orig))
-	}
-	return Duration(d), nil
-}
diff --git a/contrib/go/_std_1.18/src/time/sleep.go b/contrib/go/_std_1.18/src/time/sleep.go
deleted file mode 100644
index 1ffaabec67..0000000000
--- a/contrib/go/_std_1.18/src/time/sleep.go
+++ /dev/null
@@ -1,177 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package time
-
-// Sleep pauses the current goroutine for at least the duration d.
-// A negative or zero duration causes Sleep to return immediately.
-func Sleep(d Duration)
-
-// Interface to timers implemented in package runtime.
-// Must be in sync with ../runtime/time.go:/^type timer
-type runtimeTimer struct {
-	pp       uintptr
-	when     int64
-	period   int64
-	f        func(any, uintptr) // NOTE: must not be closure
-	arg      any
-	seq      uintptr
-	nextwhen int64
-	status   uint32
-}
-
-// when is a helper function for setting the 'when' field of a runtimeTimer.
-// It returns what the time will be, in nanoseconds, Duration d in the future.
-// If d is negative, it is ignored. If the returned value would be less than
-// zero because of an overflow, MaxInt64 is returned.
-func when(d Duration) int64 {
-	if d <= 0 {
-		return runtimeNano()
-	}
-	t := runtimeNano() + int64(d)
-	if t < 0 {
-		// N.B. runtimeNano() and d are always positive, so addition
-		// (including overflow) will never result in t == 0.
-		t = 1<<63 - 1 // math.MaxInt64
-	}
-	return t
-}
-
-func startTimer(*runtimeTimer)
-func stopTimer(*runtimeTimer) bool
-func resetTimer(*runtimeTimer, int64) bool
-func modTimer(t *runtimeTimer, when, period int64, f func(any, uintptr), arg any, seq uintptr)
-
-// The Timer type represents a single event.
-// When the Timer expires, the current time will be sent on C,
-// unless the Timer was created by AfterFunc.
-// A Timer must be created with NewTimer or AfterFunc.
-type Timer struct {
-	C <-chan Time
-	r runtimeTimer
-}
-
-// Stop prevents the Timer from firing.
-// It returns true if the call stops the timer, false if the timer has already
-// expired or been stopped.
-// Stop does not close the channel, to prevent a read from the channel succeeding
-// incorrectly.
-//
-// To ensure the channel is empty after a call to Stop, check the
-// return value and drain the channel.
-// For example, assuming the program has not received from t.C already:
-//
-// 	if !t.Stop() {
-// 		<-t.C
-// 	}
-//
-// This cannot be done concurrent to other receives from the Timer's
-// channel or other calls to the Timer's Stop method.
-//
-// For a timer created with AfterFunc(d, f), if t.Stop returns false, then the timer
-// has already expired and the function f has been started in its own goroutine;
-// Stop does not wait for f to complete before returning.
-// If the caller needs to know whether f is completed, it must coordinate
-// with f explicitly.
-func (t *Timer) Stop() bool {
-	if t.r.f == nil {
-		panic("time: Stop called on uninitialized Timer")
-	}
-	return stopTimer(&t.r)
-}
-
-// NewTimer creates a new Timer that will send
-// the current time on its channel after at least duration d.
-func NewTimer(d Duration) *Timer {
-	c := make(chan Time, 1)
-	t := &Timer{
-		C: c,
-		r: runtimeTimer{
-			when: when(d),
-			f:    sendTime,
-			arg:  c,
-		},
-	}
-	startTimer(&t.r)
-	return t
-}
-
-// Reset changes the timer to expire after duration d.
-// It returns true if the timer had been active, false if the timer had
-// expired or been stopped.
-//
-// For a Timer created with NewTimer, Reset should be invoked only on
-// stopped or expired timers with drained channels.
-//
-// If a program has already received a value from t.C, the timer is known
-// to have expired and the channel drained, so t.Reset can be used directly.
-// If a program has not yet received a value from t.C, however,
-// the timer must be stopped and—if Stop reports that the timer expired
-// before being stopped—the channel explicitly drained:
-//
-// 	if !t.Stop() {
-// 		<-t.C
-// 	}
-// 	t.Reset(d)
-//
-// This should not be done concurrent to other receives from the Timer's
-// channel.
-//
-// Note that it is not possible to use Reset's return value correctly, as there
-// is a race condition between draining the channel and the new timer expiring.
-// Reset should always be invoked on stopped or expired channels, as described above.
-// The return value exists to preserve compatibility with existing programs.
-//
-// For a Timer created with AfterFunc(d, f), Reset either reschedules
-// when f will run, in which case Reset returns true, or schedules f
-// to run again, in which case it returns false.
-// When Reset returns false, Reset neither waits for the prior f to
-// complete before returning nor does it guarantee that the subsequent
-// goroutine running f does not run concurrently with the prior
-// one. If the caller needs to know whether the prior execution of
-// f is completed, it must coordinate with f explicitly.
-func (t *Timer) Reset(d Duration) bool {
-	if t.r.f == nil {
-		panic("time: Reset called on uninitialized Timer")
-	}
-	w := when(d)
-	return resetTimer(&t.r, w)
-}
-
-// sendTime does a non-blocking send of the current time on c.
-func sendTime(c any, seq uintptr) {
-	select {
-	case c.(chan Time) <- Now():
-	default:
-	}
-}
-
-// After waits for the duration to elapse and then sends the current time
-// on the returned channel.
-// It is equivalent to NewTimer(d).C.
-// The underlying Timer is not recovered by the garbage collector
-// until the timer fires. If efficiency is a concern, use NewTimer
-// instead and call Timer.Stop if the timer is no longer needed.
-func After(d Duration) <-chan Time {
-	return NewTimer(d).C
-}
-
-// AfterFunc waits for the duration to elapse and then calls f
-// in its own goroutine. It returns a Timer that can
-// be used to cancel the call using its Stop method.
-func AfterFunc(d Duration, f func()) *Timer {
-	t := &Timer{
-		r: runtimeTimer{
-			when: when(d),
-			f:    goFunc,
-			arg:  f,
-		},
-	}
-	startTimer(&t.r)
-	return t
-}
-
-func goFunc(arg any, seq uintptr) {
-	go arg.(func())()
-}
diff --git a/contrib/go/_std_1.18/src/time/sys_unix.go b/contrib/go/_std_1.18/src/time/sys_unix.go
deleted file mode 100644
index a949a6af22..0000000000
--- a/contrib/go/_std_1.18/src/time/sys_unix.go
+++ /dev/null
@@ -1,54 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris
-
-package time
-
-import (
-	"errors"
-	"syscall"
-)
-
-// for testing: whatever interrupts a sleep
-func interrupt() {
-	syscall.Kill(syscall.Getpid(), syscall.SIGCHLD)
-}
-
-func open(name string) (uintptr, error) {
-	fd, err := syscall.Open(name, syscall.O_RDONLY, 0)
-	if err != nil {
-		return 0, err
-	}
-	return uintptr(fd), nil
-}
-
-func read(fd uintptr, buf []byte) (int, error) {
-	return syscall.Read(int(fd), buf)
-}
-
-func closefd(fd uintptr) {
-	syscall.Close(int(fd))
-}
-
-func preadn(fd uintptr, buf []byte, off int) error {
-	whence := seekStart
-	if off < 0 {
-		whence = seekEnd
-	}
-	if _, err := syscall.Seek(int(fd), int64(off), whence); err != nil {
-		return err
-	}
-	for len(buf) > 0 {
-		m, err := syscall.Read(int(fd), buf)
-		if m <= 0 {
-			if err == nil {
-				return errors.New("short read")
-			}
-			return err
-		}
-		buf = buf[m:]
-	}
-	return nil
-}
diff --git a/contrib/go/_std_1.18/src/time/tick.go b/contrib/go/_std_1.18/src/time/tick.go
deleted file mode 100644
index babf865aeb..0000000000
--- a/contrib/go/_std_1.18/src/time/tick.go
+++ /dev/null
@@ -1,73 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package time
-
-import "errors"
-
-// A Ticker holds a channel that delivers ``ticks'' of a clock
-// at intervals.
-type Ticker struct {
-	C <-chan Time // The channel on which the ticks are delivered.
-	r runtimeTimer
-}
-
-// NewTicker returns a new Ticker containing a channel that will send
-// the current time on the channel after each tick. The period of the
-// ticks is specified by the duration argument. The ticker will adjust
-// the time interval or drop ticks to make up for slow receivers.
-// The duration d must be greater than zero; if not, NewTicker will
-// panic. Stop the ticker to release associated resources.
-func NewTicker(d Duration) *Ticker {
-	if d <= 0 {
-		panic(errors.New("non-positive interval for NewTicker"))
-	}
-	// Give the channel a 1-element time buffer.
-	// If the client falls behind while reading, we drop ticks
-	// on the floor until the client catches up.
-	c := make(chan Time, 1)
-	t := &Ticker{
-		C: c,
-		r: runtimeTimer{
-			when:   when(d),
-			period: int64(d),
-			f:      sendTime,
-			arg:    c,
-		},
-	}
-	startTimer(&t.r)
-	return t
-}
-
-// Stop turns off a ticker. After Stop, no more ticks will be sent.
-// Stop does not close the channel, to prevent a concurrent goroutine
-// reading from the channel from seeing an erroneous "tick".
-func (t *Ticker) Stop() {
-	stopTimer(&t.r)
-}
-
-// Reset stops a ticker and resets its period to the specified duration.
-// The next tick will arrive after the new period elapses. The duration d
-// must be greater than zero; if not, Reset will panic.
-func (t *Ticker) Reset(d Duration) {
-	if d <= 0 {
-		panic("non-positive interval for Ticker.Reset")
-	}
-	if t.r.f == nil {
-		panic("time: Reset called on uninitialized Ticker")
-	}
-	modTimer(&t.r, when(d), int64(d), t.r.f, t.r.arg, t.r.seq)
-}
-
-// Tick is a convenience wrapper for NewTicker providing access to the ticking
-// channel only. While Tick is useful for clients that have no need to shut down
-// the Ticker, be aware that without a way to shut it down the underlying
-// Ticker cannot be recovered by the garbage collector; it "leaks".
-// Unlike NewTicker, Tick will return nil if d <= 0.
-func Tick(d Duration) <-chan Time {
-	if d <= 0 {
-		return nil
-	}
-	return NewTicker(d).C
-}
diff --git a/contrib/go/_std_1.18/src/time/time.go b/contrib/go/_std_1.18/src/time/time.go
deleted file mode 100644
index 8046ff508b..0000000000
--- a/contrib/go/_std_1.18/src/time/time.go
+++ /dev/null
@@ -1,1581 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package time provides functionality for measuring and displaying time.
-//
-// The calendrical calculations always assume a Gregorian calendar, with
-// no leap seconds.
-//
-// Monotonic Clocks
-//
-// Operating systems provide both a “wall clock,” which is subject to
-// changes for clock synchronization, and a “monotonic clock,” which is
-// not. The general rule is that the wall clock is for telling time and
-// the monotonic clock is for measuring time. Rather than split the API,
-// in this package the Time returned by time.Now contains both a wall
-// clock reading and a monotonic clock reading; later time-telling
-// operations use the wall clock reading, but later time-measuring
-// operations, specifically comparisons and subtractions, use the
-// monotonic clock reading.
-//
-// For example, this code always computes a positive elapsed time of
-// approximately 20 milliseconds, even if the wall clock is changed during
-// the operation being timed:
-//
-//	start := time.Now()
-//	... operation that takes 20 milliseconds ...
-//	t := time.Now()
-//	elapsed := t.Sub(start)
-//
-// Other idioms, such as time.Since(start), time.Until(deadline), and
-// time.Now().Before(deadline), are similarly robust against wall clock
-// resets.
-//
-// The rest of this section gives the precise details of how operations
-// use monotonic clocks, but understanding those details is not required
-// to use this package.
-//
-// The Time returned by time.Now contains a monotonic clock reading.
-// If Time t has a monotonic clock reading, t.Add adds the same duration to
-// both the wall clock and monotonic clock readings to compute the result.
-// Because t.AddDate(y, m, d), t.Round(d), and t.Truncate(d) are wall time
-// computations, they always strip any monotonic clock reading from their results.
-// Because t.In, t.Local, and t.UTC are used for their effect on the interpretation
-// of the wall time, they also strip any monotonic clock reading from their results.
-// The canonical way to strip a monotonic clock reading is to use t = t.Round(0).
-//
-// If Times t and u both contain monotonic clock readings, the operations
-// t.After(u), t.Before(u), t.Equal(u), and t.Sub(u) are carried out
-// using the monotonic clock readings alone, ignoring the wall clock
-// readings. If either t or u contains no monotonic clock reading, these
-// operations fall back to using the wall clock readings.
-//
-// On some systems the monotonic clock will stop if the computer goes to sleep.
-// On such a system, t.Sub(u) may not accurately reflect the actual
-// time that passed between t and u.
-//
-// Because the monotonic clock reading has no meaning outside
-// the current process, the serialized forms generated by t.GobEncode,
-// t.MarshalBinary, t.MarshalJSON, and t.MarshalText omit the monotonic
-// clock reading, and t.Format provides no format for it. Similarly, the
-// constructors time.Date, time.Parse, time.ParseInLocation, and time.Unix,
-// as well as the unmarshalers t.GobDecode, t.UnmarshalBinary.
-// t.UnmarshalJSON, and t.UnmarshalText always create times with
-// no monotonic clock reading.
-//
-// Note that the Go == operator compares not just the time instant but
-// also the Location and the monotonic clock reading. See the
-// documentation for the Time type for a discussion of equality
-// testing for Time values.
-//
-// For debugging, the result of t.String does include the monotonic
-// clock reading if present. If t != u because of different monotonic clock readings,
-// that difference will be visible when printing t.String() and u.String().
-//
-package time
-
-import (
-	"errors"
-	_ "unsafe" // for go:linkname
-)
-
-// A Time represents an instant in time with nanosecond precision.
-//
-// Programs using times should typically store and pass them as values,
-// not pointers. That is, time variables and struct fields should be of
-// type time.Time, not *time.Time.
-//
-// A Time value can be used by multiple goroutines simultaneously except
-// that the methods GobDecode, UnmarshalBinary, UnmarshalJSON and
-// UnmarshalText are not concurrency-safe.
-//
-// Time instants can be compared using the Before, After, and Equal methods.
-// The Sub method subtracts two instants, producing a Duration.
-// The Add method adds a Time and a Duration, producing a Time.
-//
-// The zero value of type Time is January 1, year 1, 00:00:00.000000000 UTC.
-// As this time is unlikely to come up in practice, the IsZero method gives
-// a simple way of detecting a time that has not been initialized explicitly.
-//
-// Each Time has associated with it a Location, consulted when computing the
-// presentation form of the time, such as in the Format, Hour, and Year methods.
-// The methods Local, UTC, and In return a Time with a specific location.
-// Changing the location in this way changes only the presentation; it does not
-// change the instant in time being denoted and therefore does not affect the
-// computations described in earlier paragraphs.
-//
-// Representations of a Time value saved by the GobEncode, MarshalBinary,
-// MarshalJSON, and MarshalText methods store the Time.Location's offset, but not
-// the location name. They therefore lose information about Daylight Saving Time.
-//
-// In addition to the required “wall clock” reading, a Time may contain an optional
-// reading of the current process's monotonic clock, to provide additional precision
-// for comparison or subtraction.
-// See the “Monotonic Clocks” section in the package documentation for details.
-//
-// Note that the Go == operator compares not just the time instant but also the
-// Location and the monotonic clock reading. Therefore, Time values should not
-// be used as map or database keys without first guaranteeing that the
-// identical Location has been set for all values, which can be achieved
-// through use of the UTC or Local method, and that the monotonic clock reading
-// has been stripped by setting t = t.Round(0). In general, prefer t.Equal(u)
-// to t == u, since t.Equal uses the most accurate comparison available and
-// correctly handles the case when only one of its arguments has a monotonic
-// clock reading.
-//
-type Time struct {
-	// wall and ext encode the wall time seconds, wall time nanoseconds,
-	// and optional monotonic clock reading in nanoseconds.
-	//
-	// From high to low bit position, wall encodes a 1-bit flag (hasMonotonic),
-	// a 33-bit seconds field, and a 30-bit wall time nanoseconds field.
-	// The nanoseconds field is in the range [0, 999999999].
-	// If the hasMonotonic bit is 0, then the 33-bit field must be zero
-	// and the full signed 64-bit wall seconds since Jan 1 year 1 is stored in ext.
-	// If the hasMonotonic bit is 1, then the 33-bit field holds a 33-bit
-	// unsigned wall seconds since Jan 1 year 1885, and ext holds a
-	// signed 64-bit monotonic clock reading, nanoseconds since process start.
-	wall uint64
-	ext  int64
-
-	// loc specifies the Location that should be used to
-	// determine the minute, hour, month, day, and year
-	// that correspond to this Time.
-	// The nil location means UTC.
-	// All UTC times are represented with loc==nil, never loc==&utcLoc.
-	loc *Location
-}
-
-const (
-	hasMonotonic = 1 << 63
-	maxWall      = wallToInternal + (1<<33 - 1) // year 2157
-	minWall      = wallToInternal               // year 1885
-	nsecMask     = 1<<30 - 1
-	nsecShift    = 30
-)
-
-// These helpers for manipulating the wall and monotonic clock readings
-// take pointer receivers, even when they don't modify the time,
-// to make them cheaper to call.
-
-// nsec returns the time's nanoseconds.
-func (t *Time) nsec() int32 {
-	return int32(t.wall & nsecMask)
-}
-
-// sec returns the time's seconds since Jan 1 year 1.
-func (t *Time) sec() int64 {
-	if t.wall&hasMonotonic != 0 {
-		return wallToInternal + int64(t.wall<<1>>(nsecShift+1))
-	}
-	return t.ext
-}
-
-// unixSec returns the time's seconds since Jan 1 1970 (Unix time).
-func (t *Time) unixSec() int64 { return t.sec() + internalToUnix }
-
-// addSec adds d seconds to the time.
-func (t *Time) addSec(d int64) {
-	if t.wall&hasMonotonic != 0 {
-		sec := int64(t.wall << 1 >> (nsecShift + 1))
-		dsec := sec + d
-		if 0 <= dsec && dsec <= 1<<33-1 {
-			t.wall = t.wall&nsecMask | uint64(dsec)<<nsecShift | hasMonotonic
-			return
-		}
-		// Wall second now out of range for packed field.
-		// Move to ext.
-		t.stripMono()
-	}
-
-	// Check if the sum of t.ext and d overflows and handle it properly.
-	sum := t.ext + d
-	if (sum > t.ext) == (d > 0) {
-		t.ext = sum
-	} else if d > 0 {
-		t.ext = 1<<63 - 1
-	} else {
-		t.ext = -(1<<63 - 1)
-	}
-}
-
-// setLoc sets the location associated with the time.
-func (t *Time) setLoc(loc *Location) {
-	if loc == &utcLoc {
-		loc = nil
-	}
-	t.stripMono()
-	t.loc = loc
-}
-
-// stripMono strips the monotonic clock reading in t.
-func (t *Time) stripMono() {
-	if t.wall&hasMonotonic != 0 {
-		t.ext = t.sec()
-		t.wall &= nsecMask
-	}
-}
-
-// setMono sets the monotonic clock reading in t.
-// If t cannot hold a monotonic clock reading,
-// because its wall time is too large,
-// setMono is a no-op.
-func (t *Time) setMono(m int64) {
-	if t.wall&hasMonotonic == 0 {
-		sec := t.ext
-		if sec < minWall || maxWall < sec {
-			return
-		}
-		t.wall |= hasMonotonic | uint64(sec-minWall)<<nsecShift
-	}
-	t.ext = m
-}
-
-// mono returns t's monotonic clock reading.
-// It returns 0 for a missing reading.
-// This function is used only for testing,
-// so it's OK that technically 0 is a valid
-// monotonic clock reading as well.
-func (t *Time) mono() int64 {
-	if t.wall&hasMonotonic == 0 {
-		return 0
-	}
-	return t.ext
-}
-
-// After reports whether the time instant t is after u.
-func (t Time) After(u Time) bool {
-	if t.wall&u.wall&hasMonotonic != 0 {
-		return t.ext > u.ext
-	}
-	ts := t.sec()
-	us := u.sec()
-	return ts > us || ts == us && t.nsec() > u.nsec()
-}
-
-// Before reports whether the time instant t is before u.
-func (t Time) Before(u Time) bool {
-	if t.wall&u.wall&hasMonotonic != 0 {
-		return t.ext < u.ext
-	}
-	ts := t.sec()
-	us := u.sec()
-	return ts < us || ts == us && t.nsec() < u.nsec()
-}
-
-// Equal reports whether t and u represent the same time instant.
-// Two times can be equal even if they are in different locations.
-// For example, 6:00 +0200 and 4:00 UTC are Equal.
-// See the documentation on the Time type for the pitfalls of using == with
-// Time values; most code should use Equal instead.
-func (t Time) Equal(u Time) bool {
-	if t.wall&u.wall&hasMonotonic != 0 {
-		return t.ext == u.ext
-	}
-	return t.sec() == u.sec() && t.nsec() == u.nsec()
-}
-
-// A Month specifies a month of the year (January = 1, ...).
-type Month int
-
-const (
-	January Month = 1 + iota
-	February
-	March
-	April
-	May
-	June
-	July
-	August
-	September
-	October
-	November
-	December
-)
-
-// String returns the English name of the month ("January", "February", ...).
-func (m Month) String() string {
-	if January <= m && m <= December {
-		return longMonthNames[m-1]
-	}
-	buf := make([]byte, 20)
-	n := fmtInt(buf, uint64(m))
-	return "%!Month(" + string(buf[n:]) + ")"
-}
-
-// A Weekday specifies a day of the week (Sunday = 0, ...).
-type Weekday int
-
-const (
-	Sunday Weekday = iota
-	Monday
-	Tuesday
-	Wednesday
-	Thursday
-	Friday
-	Saturday
-)
-
-// String returns the English name of the day ("Sunday", "Monday", ...).
-func (d Weekday) String() string {
-	if Sunday <= d && d <= Saturday {
-		return longDayNames[d]
-	}
-	buf := make([]byte, 20)
-	n := fmtInt(buf, uint64(d))
-	return "%!Weekday(" + string(buf[n:]) + ")"
-}
-
-// Computations on time.
-//
-// The zero value for a Time is defined to be
-//	January 1, year 1, 00:00:00.000000000 UTC
-// which (1) looks like a zero, or as close as you can get in a date
-// (1-1-1 00:00:00 UTC), (2) is unlikely enough to arise in practice to
-// be a suitable "not set" sentinel, unlike Jan 1 1970, and (3) has a
-// non-negative year even in time zones west of UTC, unlike 1-1-0
-// 00:00:00 UTC, which would be 12-31-(-1) 19:00:00 in New York.
-//
-// The zero Time value does not force a specific epoch for the time
-// representation. For example, to use the Unix epoch internally, we
-// could define that to distinguish a zero value from Jan 1 1970, that
-// time would be represented by sec=-1, nsec=1e9. However, it does
-// suggest a representation, namely using 1-1-1 00:00:00 UTC as the
-// epoch, and that's what we do.
-//
-// The Add and Sub computations are oblivious to the choice of epoch.
-//
-// The presentation computations - year, month, minute, and so on - all
-// rely heavily on division and modulus by positive constants. For
-// calendrical calculations we want these divisions to round down, even
-// for negative values, so that the remainder is always positive, but
-// Go's division (like most hardware division instructions) rounds to
-// zero. We can still do those computations and then adjust the result
-// for a negative numerator, but it's annoying to write the adjustment
-// over and over. Instead, we can change to a different epoch so long
-// ago that all the times we care about will be positive, and then round
-// to zero and round down coincide. These presentation routines already
-// have to add the zone offset, so adding the translation to the
-// alternate epoch is cheap. For example, having a non-negative time t
-// means that we can write
-//
-//	sec = t % 60
-//
-// instead of
-//
-//	sec = t % 60
-//	if sec < 0 {
-//		sec += 60
-//	}
-//
-// everywhere.
-//
-// The calendar runs on an exact 400 year cycle: a 400-year calendar
-// printed for 1970-2369 will apply as well to 2370-2769. Even the days
-// of the week match up. It simplifies the computations to choose the
-// cycle boundaries so that the exceptional years are always delayed as
-// long as possible. That means choosing a year equal to 1 mod 400, so
-// that the first leap year is the 4th year, the first missed leap year
-// is the 100th year, and the missed missed leap year is the 400th year.
-// So we'd prefer instead to print a calendar for 2001-2400 and reuse it
-// for 2401-2800.
-//
-// Finally, it's convenient if the delta between the Unix epoch and
-// long-ago epoch is representable by an int64 constant.
-//
-// These three considerations—choose an epoch as early as possible, that
-// uses a year equal to 1 mod 400, and that is no more than 2⁶³ seconds
-// earlier than 1970—bring us to the year -292277022399. We refer to
-// this year as the absolute zero year, and to times measured as a uint64
-// seconds since this year as absolute times.
-//
-// Times measured as an int64 seconds since the year 1—the representation
-// used for Time's sec field—are called internal times.
-//
-// Times measured as an int64 seconds since the year 1970 are called Unix
-// times.
-//
-// It is tempting to just use the year 1 as the absolute epoch, defining
-// that the routines are only valid for years >= 1. However, the
-// routines would then be invalid when displaying the epoch in time zones
-// west of UTC, since it is year 0. It doesn't seem tenable to say that
-// printing the zero time correctly isn't supported in half the time
-// zones. By comparison, it's reasonable to mishandle some times in
-// the year -292277022399.
-//
-// All this is opaque to clients of the API and can be changed if a
-// better implementation presents itself.
-
-const (
-	// The unsigned zero year for internal calculations.
-	// Must be 1 mod 400, and times before it will not compute correctly,
-	// but otherwise can be changed at will.
-	absoluteZeroYear = -292277022399
-
-	// The year of the zero Time.
-	// Assumed by the unixToInternal computation below.
-	internalYear = 1
-
-	// Offsets to convert between internal and absolute or Unix times.
-	absoluteToInternal int64 = (absoluteZeroYear - internalYear) * 365.2425 * secondsPerDay
-	internalToAbsolute       = -absoluteToInternal
-
-	unixToInternal int64 = (1969*365 + 1969/4 - 1969/100 + 1969/400) * secondsPerDay
-	internalToUnix int64 = -unixToInternal
-
-	wallToInternal int64 = (1884*365 + 1884/4 - 1884/100 + 1884/400) * secondsPerDay
-)
-
-// IsZero reports whether t represents the zero time instant,
-// January 1, year 1, 00:00:00 UTC.
-func (t Time) IsZero() bool {
-	return t.sec() == 0 && t.nsec() == 0
-}
-
-// abs returns the time t as an absolute time, adjusted by the zone offset.
-// It is called when computing a presentation property like Month or Hour.
-func (t Time) abs() uint64 {
-	l := t.loc
-	// Avoid function calls when possible.
-	if l == nil || l == &localLoc {
-		l = l.get()
-	}
-	sec := t.unixSec()
-	if l != &utcLoc {
-		if l.cacheZone != nil && l.cacheStart <= sec && sec < l.cacheEnd {
-			sec += int64(l.cacheZone.offset)
-		} else {
-			_, offset, _, _, _ := l.lookup(sec)
-			sec += int64(offset)
-		}
-	}
-	return uint64(sec + (unixToInternal + internalToAbsolute))
-}
-
-// locabs is a combination of the Zone and abs methods,
-// extracting both return values from a single zone lookup.
-func (t Time) locabs() (name string, offset int, abs uint64) {
-	l := t.loc
-	if l == nil || l == &localLoc {
-		l = l.get()
-	}
-	// Avoid function call if we hit the local time cache.
-	sec := t.unixSec()
-	if l != &utcLoc {
-		if l.cacheZone != nil && l.cacheStart <= sec && sec < l.cacheEnd {
-			name = l.cacheZone.name
-			offset = l.cacheZone.offset
-		} else {
-			name, offset, _, _, _ = l.lookup(sec)
-		}
-		sec += int64(offset)
-	} else {
-		name = "UTC"
-	}
-	abs = uint64(sec + (unixToInternal + internalToAbsolute))
-	return
-}
-
-// Date returns the year, month, and day in which t occurs.
-func (t Time) Date() (year int, month Month, day int) {
-	year, month, day, _ = t.date(true)
-	return
-}
-
-// Year returns the year in which t occurs.
-func (t Time) Year() int {
-	year, _, _, _ := t.date(false)
-	return year
-}
-
-// Month returns the month of the year specified by t.
-func (t Time) Month() Month {
-	_, month, _, _ := t.date(true)
-	return month
-}
-
-// Day returns the day of the month specified by t.
-func (t Time) Day() int {
-	_, _, day, _ := t.date(true)
-	return day
-}
-
-// Weekday returns the day of the week specified by t.
-func (t Time) Weekday() Weekday {
-	return absWeekday(t.abs())
-}
-
-// absWeekday is like Weekday but operates on an absolute time.
-func absWeekday(abs uint64) Weekday {
-	// January 1 of the absolute year, like January 1 of 2001, was a Monday.
-	sec := (abs + uint64(Monday)*secondsPerDay) % secondsPerWeek
-	return Weekday(int(sec) / secondsPerDay)
-}
-
-// ISOWeek returns the ISO 8601 year and week number in which t occurs.
-// Week ranges from 1 to 53. Jan 01 to Jan 03 of year n might belong to
-// week 52 or 53 of year n-1, and Dec 29 to Dec 31 might belong to week 1
-// of year n+1.
-func (t Time) ISOWeek() (year, week int) {
-	// According to the rule that the first calendar week of a calendar year is
-	// the week including the first Thursday of that year, and that the last one is
-	// the week immediately preceding the first calendar week of the next calendar year.
-	// See https://www.iso.org/obp/ui#iso:std:iso:8601:-1:ed-1:v1:en:term:3.1.1.23 for details.
-
-	// weeks start with Monday
-	// Monday Tuesday Wednesday Thursday Friday Saturday Sunday
-	// 1      2       3         4        5      6        7
-	// +3     +2      +1        0        -1     -2       -3
-	// the offset to Thursday
-	abs := t.abs()
-	d := Thursday - absWeekday(abs)
-	// handle Sunday
-	if d == 4 {
-		d = -3
-	}
-	// find the Thursday of the calendar week
-	abs += uint64(d) * secondsPerDay
-	year, _, _, yday := absDate(abs, false)
-	return year, yday/7 + 1
-}
-
-// Clock returns the hour, minute, and second within the day specified by t.
-func (t Time) Clock() (hour, min, sec int) {
-	return absClock(t.abs())
-}
-
-// absClock is like clock but operates on an absolute time.
-func absClock(abs uint64) (hour, min, sec int) {
-	sec = int(abs % secondsPerDay)
-	hour = sec / secondsPerHour
-	sec -= hour * secondsPerHour
-	min = sec / secondsPerMinute
-	sec -= min * secondsPerMinute
-	return
-}
-
-// Hour returns the hour within the day specified by t, in the range [0, 23].
-func (t Time) Hour() int {
-	return int(t.abs()%secondsPerDay) / secondsPerHour
-}
-
-// Minute returns the minute offset within the hour specified by t, in the range [0, 59].
-func (t Time) Minute() int {
-	return int(t.abs()%secondsPerHour) / secondsPerMinute
-}
-
-// Second returns the second offset within the minute specified by t, in the range [0, 59].
-func (t Time) Second() int {
-	return int(t.abs() % secondsPerMinute)
-}
-
-// Nanosecond returns the nanosecond offset within the second specified by t,
-// in the range [0, 999999999].
-func (t Time) Nanosecond() int {
-	return int(t.nsec())
-}
-
-// YearDay returns the day of the year specified by t, in the range [1,365] for non-leap years,
-// and [1,366] in leap years.
-func (t Time) YearDay() int {
-	_, _, _, yday := t.date(false)
-	return yday + 1
-}
-
-// A Duration represents the elapsed time between two instants
-// as an int64 nanosecond count. The representation limits the
-// largest representable duration to approximately 290 years.
-type Duration int64
-
-const (
-	minDuration Duration = -1 << 63
-	maxDuration Duration = 1<<63 - 1
-)
-
-// Common durations. There is no definition for units of Day or larger
-// to avoid confusion across daylight savings time zone transitions.
-//
-// To count the number of units in a Duration, divide:
-//	second := time.Second
-//	fmt.Print(int64(second/time.Millisecond)) // prints 1000
-//
-// To convert an integer number of units to a Duration, multiply:
-//	seconds := 10
-//	fmt.Print(time.Duration(seconds)*time.Second) // prints 10s
-//
-const (
-	Nanosecond  Duration = 1
-	Microsecond          = 1000 * Nanosecond
-	Millisecond          = 1000 * Microsecond
-	Second               = 1000 * Millisecond
-	Minute               = 60 * Second
-	Hour                 = 60 * Minute
-)
-
-// String returns a string representing the duration in the form "72h3m0.5s".
-// Leading zero units are omitted. As a special case, durations less than one
-// second format use a smaller unit (milli-, micro-, or nanoseconds) to ensure
-// that the leading digit is non-zero. The zero duration formats as 0s.
-func (d Duration) String() string {
-	// Largest time is 2540400h10m10.000000000s
-	var buf [32]byte
-	w := len(buf)
-
-	u := uint64(d)
-	neg := d < 0
-	if neg {
-		u = -u
-	}
-
-	if u < uint64(Second) {
-		// Special case: if duration is smaller than a second,
-		// use smaller units, like 1.2ms
-		var prec int
-		w--
-		buf[w] = 's'
-		w--
-		switch {
-		case u == 0:
-			return "0s"
-		case u < uint64(Microsecond):
-			// print nanoseconds
-			prec = 0
-			buf[w] = 'n'
-		case u < uint64(Millisecond):
-			// print microseconds
-			prec = 3
-			// U+00B5 'µ' micro sign == 0xC2 0xB5
-			w-- // Need room for two bytes.
-			copy(buf[w:], "µ")
-		default:
-			// print milliseconds
-			prec = 6
-			buf[w] = 'm'
-		}
-		w, u = fmtFrac(buf[:w], u, prec)
-		w = fmtInt(buf[:w], u)
-	} else {
-		w--
-		buf[w] = 's'
-
-		w, u = fmtFrac(buf[:w], u, 9)
-
-		// u is now integer seconds
-		w = fmtInt(buf[:w], u%60)
-		u /= 60
-
-		// u is now integer minutes
-		if u > 0 {
-			w--
-			buf[w] = 'm'
-			w = fmtInt(buf[:w], u%60)
-			u /= 60
-
-			// u is now integer hours
-			// Stop at hours because days can be different lengths.
-			if u > 0 {
-				w--
-				buf[w] = 'h'
-				w = fmtInt(buf[:w], u)
-			}
-		}
-	}
-
-	if neg {
-		w--
-		buf[w] = '-'
-	}
-
-	return string(buf[w:])
-}
-
-// fmtFrac formats the fraction of v/10**prec (e.g., ".12345") into the
-// tail of buf, omitting trailing zeros. It omits the decimal
-// point too when the fraction is 0. It returns the index where the
-// output bytes begin and the value v/10**prec.
-func fmtFrac(buf []byte, v uint64, prec int) (nw int, nv uint64) {
-	// Omit trailing zeros up to and including decimal point.
-	w := len(buf)
-	print := false
-	for i := 0; i < prec; i++ {
-		digit := v % 10
-		print = print || digit != 0
-		if print {
-			w--
-			buf[w] = byte(digit) + '0'
-		}
-		v /= 10
-	}
-	if print {
-		w--
-		buf[w] = '.'
-	}
-	return w, v
-}
-
-// fmtInt formats v into the tail of buf.
-// It returns the index where the output begins.
-func fmtInt(buf []byte, v uint64) int {
-	w := len(buf)
-	if v == 0 {
-		w--
-		buf[w] = '0'
-	} else {
-		for v > 0 {
-			w--
-			buf[w] = byte(v%10) + '0'
-			v /= 10
-		}
-	}
-	return w
-}
-
-// Nanoseconds returns the duration as an integer nanosecond count.
-func (d Duration) Nanoseconds() int64 { return int64(d) }
-
-// Microseconds returns the duration as an integer microsecond count.
-func (d Duration) Microseconds() int64 { return int64(d) / 1e3 }
-
-// Milliseconds returns the duration as an integer millisecond count.
-func (d Duration) Milliseconds() int64 { return int64(d) / 1e6 }
-
-// These methods return float64 because the dominant
-// use case is for printing a floating point number like 1.5s, and
-// a truncation to integer would make them not useful in those cases.
-// Splitting the integer and fraction ourselves guarantees that
-// converting the returned float64 to an integer rounds the same
-// way that a pure integer conversion would have, even in cases
-// where, say, float64(d.Nanoseconds())/1e9 would have rounded
-// differently.
-
-// Seconds returns the duration as a floating point number of seconds.
-func (d Duration) Seconds() float64 {
-	sec := d / Second
-	nsec := d % Second
-	return float64(sec) + float64(nsec)/1e9
-}
-
-// Minutes returns the duration as a floating point number of minutes.
-func (d Duration) Minutes() float64 {
-	min := d / Minute
-	nsec := d % Minute
-	return float64(min) + float64(nsec)/(60*1e9)
-}
-
-// Hours returns the duration as a floating point number of hours.
-func (d Duration) Hours() float64 {
-	hour := d / Hour
-	nsec := d % Hour
-	return float64(hour) + float64(nsec)/(60*60*1e9)
-}
-
-// Truncate returns the result of rounding d toward zero to a multiple of m.
-// If m <= 0, Truncate returns d unchanged.
-func (d Duration) Truncate(m Duration) Duration {
-	if m <= 0 {
-		return d
-	}
-	return d - d%m
-}
-
-// lessThanHalf reports whether x+x < y but avoids overflow,
-// assuming x and y are both positive (Duration is signed).
-func lessThanHalf(x, y Duration) bool {
-	return uint64(x)+uint64(x) < uint64(y)
-}
-
-// Round returns the result of rounding d to the nearest multiple of m.
-// The rounding behavior for halfway values is to round away from zero.
-// If the result exceeds the maximum (or minimum)
-// value that can be stored in a Duration,
-// Round returns the maximum (or minimum) duration.
-// If m <= 0, Round returns d unchanged.
-func (d Duration) Round(m Duration) Duration {
-	if m <= 0 {
-		return d
-	}
-	r := d % m
-	if d < 0 {
-		r = -r
-		if lessThanHalf(r, m) {
-			return d + r
-		}
-		if d1 := d - m + r; d1 < d {
-			return d1
-		}
-		return minDuration // overflow
-	}
-	if lessThanHalf(r, m) {
-		return d - r
-	}
-	if d1 := d + m - r; d1 > d {
-		return d1
-	}
-	return maxDuration // overflow
-}
-
-// Add returns the time t+d.
-func (t Time) Add(d Duration) Time {
-	dsec := int64(d / 1e9)
-	nsec := t.nsec() + int32(d%1e9)
-	if nsec >= 1e9 {
-		dsec++
-		nsec -= 1e9
-	} else if nsec < 0 {
-		dsec--
-		nsec += 1e9
-	}
-	t.wall = t.wall&^nsecMask | uint64(nsec) // update nsec
-	t.addSec(dsec)
-	if t.wall&hasMonotonic != 0 {
-		te := t.ext + int64(d)
-		if d < 0 && te > t.ext || d > 0 && te < t.ext {
-			// Monotonic clock reading now out of range; degrade to wall-only.
-			t.stripMono()
-		} else {
-			t.ext = te
-		}
-	}
-	return t
-}
-
-// Sub returns the duration t-u. If the result exceeds the maximum (or minimum)
-// value that can be stored in a Duration, the maximum (or minimum) duration
-// will be returned.
-// To compute t-d for a duration d, use t.Add(-d).
-func (t Time) Sub(u Time) Duration {
-	if t.wall&u.wall&hasMonotonic != 0 {
-		te := t.ext
-		ue := u.ext
-		d := Duration(te - ue)
-		if d < 0 && te > ue {
-			return maxDuration // t - u is positive out of range
-		}
-		if d > 0 && te < ue {
-			return minDuration // t - u is negative out of range
-		}
-		return d
-	}
-	d := Duration(t.sec()-u.sec())*Second + Duration(t.nsec()-u.nsec())
-	// Check for overflow or underflow.
-	switch {
-	case u.Add(d).Equal(t):
-		return d // d is correct
-	case t.Before(u):
-		return minDuration // t - u is negative out of range
-	default:
-		return maxDuration // t - u is positive out of range
-	}
-}
-
-// Since returns the time elapsed since t.
-// It is shorthand for time.Now().Sub(t).
-func Since(t Time) Duration {
-	var now Time
-	if t.wall&hasMonotonic != 0 {
-		// Common case optimization: if t has monotonic time, then Sub will use only it.
-		now = Time{hasMonotonic, runtimeNano() - startNano, nil}
-	} else {
-		now = Now()
-	}
-	return now.Sub(t)
-}
-
-// Until returns the duration until t.
-// It is shorthand for t.Sub(time.Now()).
-func Until(t Time) Duration {
-	var now Time
-	if t.wall&hasMonotonic != 0 {
-		// Common case optimization: if t has monotonic time, then Sub will use only it.
-		now = Time{hasMonotonic, runtimeNano() - startNano, nil}
-	} else {
-		now = Now()
-	}
-	return t.Sub(now)
-}
-
-// AddDate returns the time corresponding to adding the
-// given number of years, months, and days to t.
-// For example, AddDate(-1, 2, 3) applied to January 1, 2011
-// returns March 4, 2010.
-//
-// AddDate normalizes its result in the same way that Date does,
-// so, for example, adding one month to October 31 yields
-// December 1, the normalized form for November 31.
-func (t Time) AddDate(years int, months int, days int) Time {
-	year, month, day := t.Date()
-	hour, min, sec := t.Clock()
-	return Date(year+years, month+Month(months), day+days, hour, min, sec, int(t.nsec()), t.Location())
-}
-
-const (
-	secondsPerMinute = 60
-	secondsPerHour   = 60 * secondsPerMinute
-	secondsPerDay    = 24 * secondsPerHour
-	secondsPerWeek   = 7 * secondsPerDay
-	daysPer400Years  = 365*400 + 97
-	daysPer100Years  = 365*100 + 24
-	daysPer4Years    = 365*4 + 1
-)
-
-// date computes the year, day of year, and when full=true,
-// the month and day in which t occurs.
-func (t Time) date(full bool) (year int, month Month, day int, yday int) {
-	return absDate(t.abs(), full)
-}
-
-// absDate is like date but operates on an absolute time.
-func absDate(abs uint64, full bool) (year int, month Month, day int, yday int) {
-	// Split into time and day.
-	d := abs / secondsPerDay
-
-	// Account for 400 year cycles.
-	n := d / daysPer400Years
-	y := 400 * n
-	d -= daysPer400Years * n
-
-	// Cut off 100-year cycles.
-	// The last cycle has one extra leap year, so on the last day
-	// of that year, day / daysPer100Years will be 4 instead of 3.
-	// Cut it back down to 3 by subtracting n>>2.
-	n = d / daysPer100Years
-	n -= n >> 2
-	y += 100 * n
-	d -= daysPer100Years * n
-
-	// Cut off 4-year cycles.
-	// The last cycle has a missing leap year, which does not
-	// affect the computation.
-	n = d / daysPer4Years
-	y += 4 * n
-	d -= daysPer4Years * n
-
-	// Cut off years within a 4-year cycle.
-	// The last year is a leap year, so on the last day of that year,
-	// day / 365 will be 4 instead of 3. Cut it back down to 3
-	// by subtracting n>>2.
-	n = d / 365
-	n -= n >> 2
-	y += n
-	d -= 365 * n
-
-	year = int(int64(y) + absoluteZeroYear)
-	yday = int(d)
-
-	if !full {
-		return
-	}
-
-	day = yday
-	if isLeap(year) {
-		// Leap year
-		switch {
-		case day > 31+29-1:
-			// After leap day; pretend it wasn't there.
-			day--
-		case day == 31+29-1:
-			// Leap day.
-			month = February
-			day = 29
-			return
-		}
-	}
-
-	// Estimate month on assumption that every month has 31 days.
-	// The estimate may be too low by at most one month, so adjust.
-	month = Month(day / 31)
-	end := int(daysBefore[month+1])
-	var begin int
-	if day >= end {
-		month++
-		begin = end
-	} else {
-		begin = int(daysBefore[month])
-	}
-
-	month++ // because January is 1
-	day = day - begin + 1
-	return
-}
-
-// daysBefore[m] counts the number of days in a non-leap year
-// before month m begins. There is an entry for m=12, counting
-// the number of days before January of next year (365).
-var daysBefore = [...]int32{
-	0,
-	31,
-	31 + 28,
-	31 + 28 + 31,
-	31 + 28 + 31 + 30,
-	31 + 28 + 31 + 30 + 31,
-	31 + 28 + 31 + 30 + 31 + 30,
-	31 + 28 + 31 + 30 + 31 + 30 + 31,
-	31 + 28 + 31 + 30 + 31 + 30 + 31 + 31,
-	31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30,
-	31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31,
-	31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31 + 30,
-	31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31 + 30 + 31,
-}
-
-func daysIn(m Month, year int) int {
-	if m == February && isLeap(year) {
-		return 29
-	}
-	return int(daysBefore[m] - daysBefore[m-1])
-}
-
-// daysSinceEpoch takes a year and returns the number of days from
-// the absolute epoch to the start of that year.
-// This is basically (year - zeroYear) * 365, but accounting for leap days.
-func daysSinceEpoch(year int) uint64 {
-	y := uint64(int64(year) - absoluteZeroYear)
-
-	// Add in days from 400-year cycles.
-	n := y / 400
-	y -= 400 * n
-	d := daysPer400Years * n
-
-	// Add in 100-year cycles.
-	n = y / 100
-	y -= 100 * n
-	d += daysPer100Years * n
-
-	// Add in 4-year cycles.
-	n = y / 4
-	y -= 4 * n
-	d += daysPer4Years * n
-
-	// Add in non-leap years.
-	n = y
-	d += 365 * n
-
-	return d
-}
-
-// Provided by package runtime.
-func now() (sec int64, nsec int32, mono int64)
-
-// runtimeNano returns the current value of the runtime clock in nanoseconds.
-//go:linkname runtimeNano runtime.nanotime
-func runtimeNano() int64
-
-// Monotonic times are reported as offsets from startNano.
-// We initialize startNano to runtimeNano() - 1 so that on systems where
-// monotonic time resolution is fairly low (e.g. Windows 2008
-// which appears to have a default resolution of 15ms),
-// we avoid ever reporting a monotonic time of 0.
-// (Callers may want to use 0 as "time not set".)
-var startNano int64 = runtimeNano() - 1
-
-// Now returns the current local time.
-func Now() Time {
-	sec, nsec, mono := now()
-	mono -= startNano
-	sec += unixToInternal - minWall
-	if uint64(sec)>>33 != 0 {
-		return Time{uint64(nsec), sec + minWall, Local}
-	}
-	return Time{hasMonotonic | uint64(sec)<<nsecShift | uint64(nsec), mono, Local}
-}
-
-func unixTime(sec int64, nsec int32) Time {
-	return Time{uint64(nsec), sec + unixToInternal, Local}
-}
-
-// UTC returns t with the location set to UTC.
-func (t Time) UTC() Time {
-	t.setLoc(&utcLoc)
-	return t
-}
-
-// Local returns t with the location set to local time.
-func (t Time) Local() Time {
-	t.setLoc(Local)
-	return t
-}
-
-// In returns a copy of t representing the same time instant, but
-// with the copy's location information set to loc for display
-// purposes.
-//
-// In panics if loc is nil.
-func (t Time) In(loc *Location) Time {
-	if loc == nil {
-		panic("time: missing Location in call to Time.In")
-	}
-	t.setLoc(loc)
-	return t
-}
-
-// Location returns the time zone information associated with t.
-func (t Time) Location() *Location {
-	l := t.loc
-	if l == nil {
-		l = UTC
-	}
-	return l
-}
-
-// Zone computes the time zone in effect at time t, returning the abbreviated
-// name of the zone (such as "CET") and its offset in seconds east of UTC.
-func (t Time) Zone() (name string, offset int) {
-	name, offset, _, _, _ = t.loc.lookup(t.unixSec())
-	return
-}
-
-// Unix returns t as a Unix time, the number of seconds elapsed
-// since January 1, 1970 UTC. The result does not depend on the
-// location associated with t.
-// Unix-like operating systems often record time as a 32-bit
-// count of seconds, but since the method here returns a 64-bit
-// value it is valid for billions of years into the past or future.
-func (t Time) Unix() int64 {
-	return t.unixSec()
-}
-
-// UnixMilli returns t as a Unix time, the number of milliseconds elapsed since
-// January 1, 1970 UTC. The result is undefined if the Unix time in
-// milliseconds cannot be represented by an int64 (a date more than 292 million
-// years before or after 1970). The result does not depend on the
-// location associated with t.
-func (t Time) UnixMilli() int64 {
-	return t.unixSec()*1e3 + int64(t.nsec())/1e6
-}
-
-// UnixMicro returns t as a Unix time, the number of microseconds elapsed since
-// January 1, 1970 UTC. The result is undefined if the Unix time in
-// microseconds cannot be represented by an int64 (a date before year -290307 or
-// after year 294246). The result does not depend on the location associated
-// with t.
-func (t Time) UnixMicro() int64 {
-	return t.unixSec()*1e6 + int64(t.nsec())/1e3
-}
-
-// UnixNano returns t as a Unix time, the number of nanoseconds elapsed
-// since January 1, 1970 UTC. The result is undefined if the Unix time
-// in nanoseconds cannot be represented by an int64 (a date before the year
-// 1678 or after 2262). Note that this means the result of calling UnixNano
-// on the zero Time is undefined. The result does not depend on the
-// location associated with t.
-func (t Time) UnixNano() int64 {
-	return (t.unixSec())*1e9 + int64(t.nsec())
-}
-
-const (
-	timeBinaryVersionV1 byte = iota + 1 // For general situation
-	timeBinaryVersionV2                 // For LMT only
-)
-
-// MarshalBinary implements the encoding.BinaryMarshaler interface.
-func (t Time) MarshalBinary() ([]byte, error) {
-	var offsetMin int16 // minutes east of UTC. -1 is UTC.
-	var offsetSec int8
-	version := timeBinaryVersionV1
-
-	if t.Location() == UTC {
-		offsetMin = -1
-	} else {
-		_, offset := t.Zone()
-		if offset%60 != 0 {
-			version = timeBinaryVersionV2
-			offsetSec = int8(offset % 60)
-		}
-
-		offset /= 60
-		if offset < -32768 || offset == -1 || offset > 32767 {
-			return nil, errors.New("Time.MarshalBinary: unexpected zone offset")
-		}
-		offsetMin = int16(offset)
-	}
-
-	sec := t.sec()
-	nsec := t.nsec()
-	enc := []byte{
-		version,         // byte 0 : version
-		byte(sec >> 56), // bytes 1-8: seconds
-		byte(sec >> 48),
-		byte(sec >> 40),
-		byte(sec >> 32),
-		byte(sec >> 24),
-		byte(sec >> 16),
-		byte(sec >> 8),
-		byte(sec),
-		byte(nsec >> 24), // bytes 9-12: nanoseconds
-		byte(nsec >> 16),
-		byte(nsec >> 8),
-		byte(nsec),
-		byte(offsetMin >> 8), // bytes 13-14: zone offset in minutes
-		byte(offsetMin),
-	}
-	if version == timeBinaryVersionV2 {
-		enc = append(enc, byte(offsetSec))
-	}
-
-	return enc, nil
-}
-
-// UnmarshalBinary implements the encoding.BinaryUnmarshaler interface.
-func (t *Time) UnmarshalBinary(data []byte) error {
-	buf := data
-	if len(buf) == 0 {
-		return errors.New("Time.UnmarshalBinary: no data")
-	}
-
-	version := buf[0]
-	if version != timeBinaryVersionV1 && version != timeBinaryVersionV2 {
-		return errors.New("Time.UnmarshalBinary: unsupported version")
-	}
-
-	wantLen := /*version*/ 1 + /*sec*/ 8 + /*nsec*/ 4 + /*zone offset*/ 2
-	if version == timeBinaryVersionV2 {
-		wantLen++
-	}
-	if len(buf) != wantLen {
-		return errors.New("Time.UnmarshalBinary: invalid length")
-	}
-
-	buf = buf[1:]
-	sec := int64(buf[7]) | int64(buf[6])<<8 | int64(buf[5])<<16 | int64(buf[4])<<24 |
-		int64(buf[3])<<32 | int64(buf[2])<<40 | int64(buf[1])<<48 | int64(buf[0])<<56
-
-	buf = buf[8:]
-	nsec := int32(buf[3]) | int32(buf[2])<<8 | int32(buf[1])<<16 | int32(buf[0])<<24
-
-	buf = buf[4:]
-	offset := int(int16(buf[1])|int16(buf[0])<<8) * 60
-	if version == timeBinaryVersionV2 {
-		offset += int(buf[2])
-	}
-
-	*t = Time{}
-	t.wall = uint64(nsec)
-	t.ext = sec
-
-	if offset == -1*60 {
-		t.setLoc(&utcLoc)
-	} else if _, localoff, _, _, _ := Local.lookup(t.unixSec()); offset == localoff {
-		t.setLoc(Local)
-	} else {
-		t.setLoc(FixedZone("", offset))
-	}
-
-	return nil
-}
-
-// TODO(rsc): Remove GobEncoder, GobDecoder, MarshalJSON, UnmarshalJSON in Go 2.
-// The same semantics will be provided by the generic MarshalBinary, MarshalText,
-// UnmarshalBinary, UnmarshalText.
-
-// GobEncode implements the gob.GobEncoder interface.
-func (t Time) GobEncode() ([]byte, error) {
-	return t.MarshalBinary()
-}
-
-// GobDecode implements the gob.GobDecoder interface.
-func (t *Time) GobDecode(data []byte) error {
-	return t.UnmarshalBinary(data)
-}
-
-// MarshalJSON implements the json.Marshaler interface.
-// The time is a quoted string in RFC 3339 format, with sub-second precision added if present.
-func (t Time) MarshalJSON() ([]byte, error) {
-	if y := t.Year(); y < 0 || y >= 10000 {
-		// RFC 3339 is clear that years are 4 digits exactly.
-		// See golang.org/issue/4556#c15 for more discussion.
-		return nil, errors.New("Time.MarshalJSON: year outside of range [0,9999]")
-	}
-
-	b := make([]byte, 0, len(RFC3339Nano)+2)
-	b = append(b, '"')
-	b = t.AppendFormat(b, RFC3339Nano)
-	b = append(b, '"')
-	return b, nil
-}
-
-// UnmarshalJSON implements the json.Unmarshaler interface.
-// The time is expected to be a quoted string in RFC 3339 format.
-func (t *Time) UnmarshalJSON(data []byte) error {
-	// Ignore null, like in the main JSON package.
-	if string(data) == "null" {
-		return nil
-	}
-	// Fractional seconds are handled implicitly by Parse.
-	var err error
-	*t, err = Parse(`"`+RFC3339+`"`, string(data))
-	return err
-}
-
-// MarshalText implements the encoding.TextMarshaler interface.
-// The time is formatted in RFC 3339 format, with sub-second precision added if present.
-func (t Time) MarshalText() ([]byte, error) {
-	if y := t.Year(); y < 0 || y >= 10000 {
-		return nil, errors.New("Time.MarshalText: year outside of range [0,9999]")
-	}
-
-	b := make([]byte, 0, len(RFC3339Nano))
-	return t.AppendFormat(b, RFC3339Nano), nil
-}
-
-// UnmarshalText implements the encoding.TextUnmarshaler interface.
-// The time is expected to be in RFC 3339 format.
-func (t *Time) UnmarshalText(data []byte) error {
-	// Fractional seconds are handled implicitly by Parse.
-	var err error
-	*t, err = Parse(RFC3339, string(data))
-	return err
-}
-
-// Unix returns the local Time corresponding to the given Unix time,
-// sec seconds and nsec nanoseconds since January 1, 1970 UTC.
-// It is valid to pass nsec outside the range [0, 999999999].
-// Not all sec values have a corresponding time value. One such
-// value is 1<<63-1 (the largest int64 value).
-func Unix(sec int64, nsec int64) Time {
-	if nsec < 0 || nsec >= 1e9 {
-		n := nsec / 1e9
-		sec += n
-		nsec -= n * 1e9
-		if nsec < 0 {
-			nsec += 1e9
-			sec--
-		}
-	}
-	return unixTime(sec, int32(nsec))
-}
-
-// UnixMilli returns the local Time corresponding to the given Unix time,
-// msec milliseconds since January 1, 1970 UTC.
-func UnixMilli(msec int64) Time {
-	return Unix(msec/1e3, (msec%1e3)*1e6)
-}
-
-// UnixMicro returns the local Time corresponding to the given Unix time,
-// usec microseconds since January 1, 1970 UTC.
-func UnixMicro(usec int64) Time {
-	return Unix(usec/1e6, (usec%1e6)*1e3)
-}
-
-// IsDST reports whether the time in the configured location is in Daylight Savings Time.
-func (t Time) IsDST() bool {
-	_, _, _, _, isDST := t.loc.lookup(t.Unix())
-	return isDST
-}
-
-func isLeap(year int) bool {
-	return year%4 == 0 && (year%100 != 0 || year%400 == 0)
-}
-
-// norm returns nhi, nlo such that
-//	hi * base + lo == nhi * base + nlo
-//	0 <= nlo < base
-func norm(hi, lo, base int) (nhi, nlo int) {
-	if lo < 0 {
-		n := (-lo-1)/base + 1
-		hi -= n
-		lo += n * base
-	}
-	if lo >= base {
-		n := lo / base
-		hi += n
-		lo -= n * base
-	}
-	return hi, lo
-}
-
-// Date returns the Time corresponding to
-//	yyyy-mm-dd hh:mm:ss + nsec nanoseconds
-// in the appropriate zone for that time in the given location.
-//
-// The month, day, hour, min, sec, and nsec values may be outside
-// their usual ranges and will be normalized during the conversion.
-// For example, October 32 converts to November 1.
-//
-// A daylight savings time transition skips or repeats times.
-// For example, in the United States, March 13, 2011 2:15am never occurred,
-// while November 6, 2011 1:15am occurred twice. In such cases, the
-// choice of time zone, and therefore the time, is not well-defined.
-// Date returns a time that is correct in one of the two zones involved
-// in the transition, but it does not guarantee which.
-//
-// Date panics if loc is nil.
-func Date(year int, month Month, day, hour, min, sec, nsec int, loc *Location) Time {
-	if loc == nil {
-		panic("time: missing Location in call to Date")
-	}
-
-	// Normalize month, overflowing into year.
-	m := int(month) - 1
-	year, m = norm(year, m, 12)
-	month = Month(m) + 1
-
-	// Normalize nsec, sec, min, hour, overflowing into day.
-	sec, nsec = norm(sec, nsec, 1e9)
-	min, sec = norm(min, sec, 60)
-	hour, min = norm(hour, min, 60)
-	day, hour = norm(day, hour, 24)
-
-	// Compute days since the absolute epoch.
-	d := daysSinceEpoch(year)
-
-	// Add in days before this month.
-	d += uint64(daysBefore[month-1])
-	if isLeap(year) && month >= March {
-		d++ // February 29
-	}
-
-	// Add in days before today.
-	d += uint64(day - 1)
-
-	// Add in time elapsed today.
-	abs := d * secondsPerDay
-	abs += uint64(hour*secondsPerHour + min*secondsPerMinute + sec)
-
-	unix := int64(abs) + (absoluteToInternal + internalToUnix)
-
-	// Look for zone offset for expected time, so we can adjust to UTC.
-	// The lookup function expects UTC, so first we pass unix in the
-	// hope that it will not be too close to a zone transition,
-	// and then adjust if it is.
-	_, offset, start, end, _ := loc.lookup(unix)
-	if offset != 0 {
-		utc := unix - int64(offset)
-		// If utc is valid for the time zone we found, then we have the right offset.
-		// If not, we get the correct offset by looking up utc in the location.
-		if utc < start || utc >= end {
-			_, offset, _, _, _ = loc.lookup(utc)
-		}
-		unix -= int64(offset)
-	}
-
-	t := unixTime(unix, int32(nsec))
-	t.setLoc(loc)
-	return t
-}
-
-// Truncate returns the result of rounding t down to a multiple of d (since the zero time).
-// If d <= 0, Truncate returns t stripped of any monotonic clock reading but otherwise unchanged.
-//
-// Truncate operates on the time as an absolute duration since the
-// zero time; it does not operate on the presentation form of the
-// time. Thus, Truncate(Hour) may return a time with a non-zero
-// minute, depending on the time's Location.
-func (t Time) Truncate(d Duration) Time {
-	t.stripMono()
-	if d <= 0 {
-		return t
-	}
-	_, r := div(t, d)
-	return t.Add(-r)
-}
-
-// Round returns the result of rounding t to the nearest multiple of d (since the zero time).
-// The rounding behavior for halfway values is to round up.
-// If d <= 0, Round returns t stripped of any monotonic clock reading but otherwise unchanged.
-//
-// Round operates on the time as an absolute duration since the
-// zero time; it does not operate on the presentation form of the
-// time. Thus, Round(Hour) may return a time with a non-zero
-// minute, depending on the time's Location.
-func (t Time) Round(d Duration) Time {
-	t.stripMono()
-	if d <= 0 {
-		return t
-	}
-	_, r := div(t, d)
-	if lessThanHalf(r, d) {
-		return t.Add(-r)
-	}
-	return t.Add(d - r)
-}
-
-// div divides t by d and returns the quotient parity and remainder.
-// We don't use the quotient parity anymore (round half up instead of round to even)
-// but it's still here in case we change our minds.
-func div(t Time, d Duration) (qmod2 int, r Duration) {
-	neg := false
-	nsec := t.nsec()
-	sec := t.sec()
-	if sec < 0 {
-		// Operate on absolute value.
-		neg = true
-		sec = -sec
-		nsec = -nsec
-		if nsec < 0 {
-			nsec += 1e9
-			sec-- // sec >= 1 before the -- so safe
-		}
-	}
-
-	switch {
-	// Special case: 2d divides 1 second.
-	case d < Second && Second%(d+d) == 0:
-		qmod2 = int(nsec/int32(d)) & 1
-		r = Duration(nsec % int32(d))
-
-	// Special case: d is a multiple of 1 second.
-	case d%Second == 0:
-		d1 := int64(d / Second)
-		qmod2 = int(sec/d1) & 1
-		r = Duration(sec%d1)*Second + Duration(nsec)
-
-	// General case.
-	// This could be faster if more cleverness were applied,
-	// but it's really only here to avoid special case restrictions in the API.
-	// No one will care about these cases.
-	default:
-		// Compute nanoseconds as 128-bit number.
-		sec := uint64(sec)
-		tmp := (sec >> 32) * 1e9
-		u1 := tmp >> 32
-		u0 := tmp << 32
-		tmp = (sec & 0xFFFFFFFF) * 1e9
-		u0x, u0 := u0, u0+tmp
-		if u0 < u0x {
-			u1++
-		}
-		u0x, u0 = u0, u0+uint64(nsec)
-		if u0 < u0x {
-			u1++
-		}
-
-		// Compute remainder by subtracting r<<k for decreasing k.
-		// Quotient parity is whether we subtract on last round.
-		d1 := uint64(d)
-		for d1>>63 != 1 {
-			d1 <<= 1
-		}
-		d0 := uint64(0)
-		for {
-			qmod2 = 0
-			if u1 > d1 || u1 == d1 && u0 >= d0 {
-				// subtract
-				qmod2 = 1
-				u0x, u0 = u0, u0-d0
-				if u0 > u0x {
-					u1--
-				}
-				u1 -= d1
-			}
-			if d1 == 0 && d0 == uint64(d) {
-				break
-			}
-			d0 >>= 1
-			d0 |= (d1 & 1) << 63
-			d1 >>= 1
-		}
-		r = Duration(u0)
-	}
-
-	if neg && r != 0 {
-		// If input was negative and not an exact multiple of d, we computed q, r such that
-		//	q*d + r = -t
-		// But the right answers are given by -(q-1), d-r:
-		//	q*d + r = -t
-		//	-q*d - r = t
-		//	-(q-1)*d + (d - r) = t
-		qmod2 ^= 1
-		r = d - r
-	}
-	return
-}
diff --git a/contrib/go/_std_1.18/src/time/zoneinfo.go b/contrib/go/_std_1.18/src/time/zoneinfo.go
deleted file mode 100644
index 7b39f869e6..0000000000
--- a/contrib/go/_std_1.18/src/time/zoneinfo.go
+++ /dev/null
@@ -1,687 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package time
-
-import (
-	"errors"
-	"sync"
-	"syscall"
-)
-
-//go:generate env ZONEINFO=$GOROOT/lib/time/zoneinfo.zip go run genzabbrs.go -output zoneinfo_abbrs_windows.go
-
-// A Location maps time instants to the zone in use at that time.
-// Typically, the Location represents the collection of time offsets
-// in use in a geographical area. For many Locations the time offset varies
-// depending on whether daylight savings time is in use at the time instant.
-type Location struct {
-	name string
-	zone []zone
-	tx   []zoneTrans
-
-	// The tzdata information can be followed by a string that describes
-	// how to handle DST transitions not recorded in zoneTrans.
-	// The format is the TZ environment variable without a colon; see
-	// https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap08.html.
-	// Example string, for America/Los_Angeles: PST8PDT,M3.2.0,M11.1.0
-	extend string
-
-	// Most lookups will be for the current time.
-	// To avoid the binary search through tx, keep a
-	// static one-element cache that gives the correct
-	// zone for the time when the Location was created.
-	// if cacheStart <= t < cacheEnd,
-	// lookup can return cacheZone.
-	// The units for cacheStart and cacheEnd are seconds
-	// since January 1, 1970 UTC, to match the argument
-	// to lookup.
-	cacheStart int64
-	cacheEnd   int64
-	cacheZone  *zone
-}
-
-// A zone represents a single time zone such as CET.
-type zone struct {
-	name   string // abbreviated name, "CET"
-	offset int    // seconds east of UTC
-	isDST  bool   // is this zone Daylight Savings Time?
-}
-
-// A zoneTrans represents a single time zone transition.
-type zoneTrans struct {
-	when         int64 // transition time, in seconds since 1970 GMT
-	index        uint8 // the index of the zone that goes into effect at that time
-	isstd, isutc bool  // ignored - no idea what these mean
-}
-
-// alpha and omega are the beginning and end of time for zone
-// transitions.
-const (
-	alpha = -1 << 63  // math.MinInt64
-	omega = 1<<63 - 1 // math.MaxInt64
-)
-
-// UTC represents Universal Coordinated Time (UTC).
-var UTC *Location = &utcLoc
-
-// utcLoc is separate so that get can refer to &utcLoc
-// and ensure that it never returns a nil *Location,
-// even if a badly behaved client has changed UTC.
-var utcLoc = Location{name: "UTC"}
-
-// Local represents the system's local time zone.
-// On Unix systems, Local consults the TZ environment
-// variable to find the time zone to use. No TZ means
-// use the system default /etc/localtime.
-// TZ="" means use UTC.
-// TZ="foo" means use file foo in the system timezone directory.
-var Local *Location = &localLoc
-
-// localLoc is separate so that initLocal can initialize
-// it even if a client has changed Local.
-var localLoc Location
-var localOnce sync.Once
-
-func (l *Location) get() *Location {
-	if l == nil {
-		return &utcLoc
-	}
-	if l == &localLoc {
-		localOnce.Do(initLocal)
-	}
-	return l
-}
-
-// String returns a descriptive name for the time zone information,
-// corresponding to the name argument to LoadLocation or FixedZone.
-func (l *Location) String() string {
-	return l.get().name
-}
-
-// FixedZone returns a Location that always uses
-// the given zone name and offset (seconds east of UTC).
-func FixedZone(name string, offset int) *Location {
-	l := &Location{
-		name:       name,
-		zone:       []zone{{name, offset, false}},
-		tx:         []zoneTrans{{alpha, 0, false, false}},
-		cacheStart: alpha,
-		cacheEnd:   omega,
-	}
-	l.cacheZone = &l.zone[0]
-	return l
-}
-
-// lookup returns information about the time zone in use at an
-// instant in time expressed as seconds since January 1, 1970 00:00:00 UTC.
-//
-// The returned information gives the name of the zone (such as "CET"),
-// the start and end times bracketing sec when that zone is in effect,
-// the offset in seconds east of UTC (such as -5*60*60), and whether
-// the daylight savings is being observed at that time.
-func (l *Location) lookup(sec int64) (name string, offset int, start, end int64, isDST bool) {
-	l = l.get()
-
-	if len(l.zone) == 0 {
-		name = "UTC"
-		offset = 0
-		start = alpha
-		end = omega
-		isDST = false
-		return
-	}
-
-	if zone := l.cacheZone; zone != nil && l.cacheStart <= sec && sec < l.cacheEnd {
-		name = zone.name
-		offset = zone.offset
-		start = l.cacheStart
-		end = l.cacheEnd
-		isDST = zone.isDST
-		return
-	}
-
-	if len(l.tx) == 0 || sec < l.tx[0].when {
-		zone := &l.zone[l.lookupFirstZone()]
-		name = zone.name
-		offset = zone.offset
-		start = alpha
-		if len(l.tx) > 0 {
-			end = l.tx[0].when
-		} else {
-			end = omega
-		}
-		isDST = zone.isDST
-		return
-	}
-
-	// Binary search for entry with largest time <= sec.
-	// Not using sort.Search to avoid dependencies.
-	tx := l.tx
-	end = omega
-	lo := 0
-	hi := len(tx)
-	for hi-lo > 1 {
-		m := lo + (hi-lo)/2
-		lim := tx[m].when
-		if sec < lim {
-			end = lim
-			hi = m
-		} else {
-			lo = m
-		}
-	}
-	zone := &l.zone[tx[lo].index]
-	name = zone.name
-	offset = zone.offset
-	start = tx[lo].when
-	// end = maintained during the search
-	isDST = zone.isDST
-
-	// If we're at the end of the known zone transitions,
-	// try the extend string.
-	if lo == len(tx)-1 && l.extend != "" {
-		if ename, eoffset, estart, eend, eisDST, ok := tzset(l.extend, end, sec); ok {
-			return ename, eoffset, estart, eend, eisDST
-		}
-	}
-
-	return
-}
-
-// lookupFirstZone returns the index of the time zone to use for times
-// before the first transition time, or when there are no transition
-// times.
-//
-// The reference implementation in localtime.c from
-// https://www.iana.org/time-zones/repository/releases/tzcode2013g.tar.gz
-// implements the following algorithm for these cases:
-// 1) If the first zone is unused by the transitions, use it.
-// 2) Otherwise, if there are transition times, and the first
-//    transition is to a zone in daylight time, find the first
-//    non-daylight-time zone before and closest to the first transition
-//    zone.
-// 3) Otherwise, use the first zone that is not daylight time, if
-//    there is one.
-// 4) Otherwise, use the first zone.
-func (l *Location) lookupFirstZone() int {
-	// Case 1.
-	if !l.firstZoneUsed() {
-		return 0
-	}
-
-	// Case 2.
-	if len(l.tx) > 0 && l.zone[l.tx[0].index].isDST {
-		for zi := int(l.tx[0].index) - 1; zi >= 0; zi-- {
-			if !l.zone[zi].isDST {
-				return zi
-			}
-		}
-	}
-
-	// Case 3.
-	for zi := range l.zone {
-		if !l.zone[zi].isDST {
-			return zi
-		}
-	}
-
-	// Case 4.
-	return 0
-}
-
-// firstZoneUsed reports whether the first zone is used by some
-// transition.
-func (l *Location) firstZoneUsed() bool {
-	for _, tx := range l.tx {
-		if tx.index == 0 {
-			return true
-		}
-	}
-	return false
-}
-
-// tzset takes a timezone string like the one found in the TZ environment
-// variable, the end of the last time zone transition expressed as seconds
-// since January 1, 1970 00:00:00 UTC, and a time expressed the same way.
-// We call this a tzset string since in C the function tzset reads TZ.
-// The return values are as for lookup, plus ok which reports whether the
-// parse succeeded.
-func tzset(s string, initEnd, sec int64) (name string, offset int, start, end int64, isDST, ok bool) {
-	var (
-		stdName, dstName     string
-		stdOffset, dstOffset int
-	)
-
-	stdName, s, ok = tzsetName(s)
-	if ok {
-		stdOffset, s, ok = tzsetOffset(s)
-	}
-	if !ok {
-		return "", 0, 0, 0, false, false
-	}
-
-	// The numbers in the tzset string are added to local time to get UTC,
-	// but our offsets are added to UTC to get local time,
-	// so we negate the number we see here.
-	stdOffset = -stdOffset
-
-	if len(s) == 0 || s[0] == ',' {
-		// No daylight savings time.
-		return stdName, stdOffset, initEnd, omega, false, true
-	}
-
-	dstName, s, ok = tzsetName(s)
-	if ok {
-		if len(s) == 0 || s[0] == ',' {
-			dstOffset = stdOffset + secondsPerHour
-		} else {
-			dstOffset, s, ok = tzsetOffset(s)
-			dstOffset = -dstOffset // as with stdOffset, above
-		}
-	}
-	if !ok {
-		return "", 0, 0, 0, false, false
-	}
-
-	if len(s) == 0 {
-		// Default DST rules per tzcode.
-		s = ",M3.2.0,M11.1.0"
-	}
-	// The TZ definition does not mention ';' here but tzcode accepts it.
-	if s[0] != ',' && s[0] != ';' {
-		return "", 0, 0, 0, false, false
-	}
-	s = s[1:]
-
-	var startRule, endRule rule
-	startRule, s, ok = tzsetRule(s)
-	if !ok || len(s) == 0 || s[0] != ',' {
-		return "", 0, 0, 0, false, false
-	}
-	s = s[1:]
-	endRule, s, ok = tzsetRule(s)
-	if !ok || len(s) > 0 {
-		return "", 0, 0, 0, false, false
-	}
-
-	year, _, _, yday := absDate(uint64(sec+unixToInternal+internalToAbsolute), false)
-
-	ysec := int64(yday*secondsPerDay) + sec%secondsPerDay
-
-	// Compute start of year in seconds since Unix epoch.
-	d := daysSinceEpoch(year)
-	abs := int64(d * secondsPerDay)
-	abs += absoluteToInternal + internalToUnix
-
-	startSec := int64(tzruleTime(year, startRule, stdOffset))
-	endSec := int64(tzruleTime(year, endRule, dstOffset))
-	dstIsDST, stdIsDST := true, false
-	// Note: this is a flipping of "DST" and "STD" while retaining the labels
-	// This happens in southern hemispheres. The labelling here thus is a little
-	// inconsistent with the goal.
-	if endSec < startSec {
-		startSec, endSec = endSec, startSec
-		stdName, dstName = dstName, stdName
-		stdOffset, dstOffset = dstOffset, stdOffset
-		stdIsDST, dstIsDST = dstIsDST, stdIsDST
-	}
-
-	// The start and end values that we return are accurate
-	// close to a daylight savings transition, but are otherwise
-	// just the start and end of the year. That suffices for
-	// the only caller that cares, which is Date.
-	if ysec < startSec {
-		return stdName, stdOffset, abs, startSec + abs, stdIsDST, true
-	} else if ysec >= endSec {
-		return stdName, stdOffset, endSec + abs, abs + 365*secondsPerDay, stdIsDST, true
-	} else {
-		return dstName, dstOffset, startSec + abs, endSec + abs, dstIsDST, true
-	}
-}
-
-// tzsetName returns the timezone name at the start of the tzset string s,
-// and the remainder of s, and reports whether the parsing is OK.
-func tzsetName(s string) (string, string, bool) {
-	if len(s) == 0 {
-		return "", "", false
-	}
-	if s[0] != '<' {
-		for i, r := range s {
-			switch r {
-			case '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', ',', '-', '+':
-				if i < 3 {
-					return "", "", false
-				}
-				return s[:i], s[i:], true
-			}
-		}
-		if len(s) < 3 {
-			return "", "", false
-		}
-		return s, "", true
-	} else {
-		for i, r := range s {
-			if r == '>' {
-				return s[1:i], s[i+1:], true
-			}
-		}
-		return "", "", false
-	}
-}
-
-// tzsetOffset returns the timezone offset at the start of the tzset string s,
-// and the remainder of s, and reports whether the parsing is OK.
-// The timezone offset is returned as a number of seconds.
-func tzsetOffset(s string) (offset int, rest string, ok bool) {
-	if len(s) == 0 {
-		return 0, "", false
-	}
-	neg := false
-	if s[0] == '+' {
-		s = s[1:]
-	} else if s[0] == '-' {
-		s = s[1:]
-		neg = true
-	}
-
-	// The tzdata code permits values up to 24 * 7 here,
-	// although POSIX does not.
-	var hours int
-	hours, s, ok = tzsetNum(s, 0, 24*7)
-	if !ok {
-		return 0, "", false
-	}
-	off := hours * secondsPerHour
-	if len(s) == 0 || s[0] != ':' {
-		if neg {
-			off = -off
-		}
-		return off, s, true
-	}
-
-	var mins int
-	mins, s, ok = tzsetNum(s[1:], 0, 59)
-	if !ok {
-		return 0, "", false
-	}
-	off += mins * secondsPerMinute
-	if len(s) == 0 || s[0] != ':' {
-		if neg {
-			off = -off
-		}
-		return off, s, true
-	}
-
-	var secs int
-	secs, s, ok = tzsetNum(s[1:], 0, 59)
-	if !ok {
-		return 0, "", false
-	}
-	off += secs
-
-	if neg {
-		off = -off
-	}
-	return off, s, true
-}
-
-// ruleKind is the kinds of rules that can be seen in a tzset string.
-type ruleKind int
-
-const (
-	ruleJulian ruleKind = iota
-	ruleDOY
-	ruleMonthWeekDay
-)
-
-// rule is a rule read from a tzset string.
-type rule struct {
-	kind ruleKind
-	day  int
-	week int
-	mon  int
-	time int // transition time
-}
-
-// tzsetRule parses a rule from a tzset string.
-// It returns the rule, and the remainder of the string, and reports success.
-func tzsetRule(s string) (rule, string, bool) {
-	var r rule
-	if len(s) == 0 {
-		return rule{}, "", false
-	}
-	ok := false
-	if s[0] == 'J' {
-		var jday int
-		jday, s, ok = tzsetNum(s[1:], 1, 365)
-		if !ok {
-			return rule{}, "", false
-		}
-		r.kind = ruleJulian
-		r.day = jday
-	} else if s[0] == 'M' {
-		var mon int
-		mon, s, ok = tzsetNum(s[1:], 1, 12)
-		if !ok || len(s) == 0 || s[0] != '.' {
-			return rule{}, "", false
-
-		}
-		var week int
-		week, s, ok = tzsetNum(s[1:], 1, 5)
-		if !ok || len(s) == 0 || s[0] != '.' {
-			return rule{}, "", false
-		}
-		var day int
-		day, s, ok = tzsetNum(s[1:], 0, 6)
-		if !ok {
-			return rule{}, "", false
-		}
-		r.kind = ruleMonthWeekDay
-		r.day = day
-		r.week = week
-		r.mon = mon
-	} else {
-		var day int
-		day, s, ok = tzsetNum(s, 0, 365)
-		if !ok {
-			return rule{}, "", false
-		}
-		r.kind = ruleDOY
-		r.day = day
-	}
-
-	if len(s) == 0 || s[0] != '/' {
-		r.time = 2 * secondsPerHour // 2am is the default
-		return r, s, true
-	}
-
-	offset, s, ok := tzsetOffset(s[1:])
-	if !ok {
-		return rule{}, "", false
-	}
-	r.time = offset
-
-	return r, s, true
-}
-
-// tzsetNum parses a number from a tzset string.
-// It returns the number, and the remainder of the string, and reports success.
-// The number must be between min and max.
-func tzsetNum(s string, min, max int) (num int, rest string, ok bool) {
-	if len(s) == 0 {
-		return 0, "", false
-	}
-	num = 0
-	for i, r := range s {
-		if r < '0' || r > '9' {
-			if i == 0 || num < min {
-				return 0, "", false
-			}
-			return num, s[i:], true
-		}
-		num *= 10
-		num += int(r) - '0'
-		if num > max {
-			return 0, "", false
-		}
-	}
-	if num < min {
-		return 0, "", false
-	}
-	return num, "", true
-}
-
-// tzruleTime takes a year, a rule, and a timezone offset,
-// and returns the number of seconds since the start of the year
-// that the rule takes effect.
-func tzruleTime(year int, r rule, off int) int {
-	var s int
-	switch r.kind {
-	case ruleJulian:
-		s = (r.day - 1) * secondsPerDay
-		if isLeap(year) && r.day >= 60 {
-			s += secondsPerDay
-		}
-	case ruleDOY:
-		s = r.day * secondsPerDay
-	case ruleMonthWeekDay:
-		// Zeller's Congruence.
-		m1 := (r.mon+9)%12 + 1
-		yy0 := year
-		if r.mon <= 2 {
-			yy0--
-		}
-		yy1 := yy0 / 100
-		yy2 := yy0 % 100
-		dow := ((26*m1-2)/10 + 1 + yy2 + yy2/4 + yy1/4 - 2*yy1) % 7
-		if dow < 0 {
-			dow += 7
-		}
-		// Now dow is the day-of-week of the first day of r.mon.
-		// Get the day-of-month of the first "dow" day.
-		d := r.day - dow
-		if d < 0 {
-			d += 7
-		}
-		for i := 1; i < r.week; i++ {
-			if d+7 >= daysIn(Month(r.mon), year) {
-				break
-			}
-			d += 7
-		}
-		d += int(daysBefore[r.mon-1])
-		if isLeap(year) && r.mon > 2 {
-			d++
-		}
-		s = d * secondsPerDay
-	}
-
-	return s + r.time - off
-}
-
-// lookupName returns information about the time zone with
-// the given name (such as "EST") at the given pseudo-Unix time
-// (what the given time of day would be in UTC).
-func (l *Location) lookupName(name string, unix int64) (offset int, ok bool) {
-	l = l.get()
-
-	// First try for a zone with the right name that was actually
-	// in effect at the given time. (In Sydney, Australia, both standard
-	// and daylight-savings time are abbreviated "EST". Using the
-	// offset helps us pick the right one for the given time.
-	// It's not perfect: during the backward transition we might pick
-	// either one.)
-	for i := range l.zone {
-		zone := &l.zone[i]
-		if zone.name == name {
-			nam, offset, _, _, _ := l.lookup(unix - int64(zone.offset))
-			if nam == zone.name {
-				return offset, true
-			}
-		}
-	}
-
-	// Otherwise fall back to an ordinary name match.
-	for i := range l.zone {
-		zone := &l.zone[i]
-		if zone.name == name {
-			return zone.offset, true
-		}
-	}
-
-	// Otherwise, give up.
-	return
-}
-
-// NOTE(rsc): Eventually we will need to accept the POSIX TZ environment
-// syntax too, but I don't feel like implementing it today.
-
-var errLocation = errors.New("time: invalid location name")
-
-var zoneinfo *string
-var zoneinfoOnce sync.Once
-
-// LoadLocation returns the Location with the given name.
-//
-// If the name is "" or "UTC", LoadLocation returns UTC.
-// If the name is "Local", LoadLocation returns Local.
-//
-// Otherwise, the name is taken to be a location name corresponding to a file
-// in the IANA Time Zone database, such as "America/New_York".
-//
-// LoadLocation looks for the IANA Time Zone database in the following
-// locations in order:
-//
-// - the directory or uncompressed zip file named by the ZONEINFO environment variable
-// - on a Unix system, the system standard installation location
-// - $GOROOT/lib/time/zoneinfo.zip
-// - the time/tzdata package, if it was imported
-func LoadLocation(name string) (*Location, error) {
-	if name == "" || name == "UTC" {
-		return UTC, nil
-	}
-	if name == "Local" {
-		return Local, nil
-	}
-	if containsDotDot(name) || name[0] == '/' || name[0] == '\\' {
-		// No valid IANA Time Zone name contains a single dot,
-		// much less dot dot. Likewise, none begin with a slash.
-		return nil, errLocation
-	}
-	zoneinfoOnce.Do(func() {
-		env, _ := syscall.Getenv("ZONEINFO")
-		zoneinfo = &env
-	})
-	var firstErr error
-	if *zoneinfo != "" {
-		if zoneData, err := loadTzinfoFromDirOrZip(*zoneinfo, name); err == nil {
-			if z, err := LoadLocationFromTZData(name, zoneData); err == nil {
-				return z, nil
-			}
-			firstErr = err
-		} else if err != syscall.ENOENT {
-			firstErr = err
-		}
-	}
-	if z, err := loadLocation(name, zoneSources); err == nil {
-		return z, nil
-	} else if firstErr == nil {
-		firstErr = err
-	}
-	return nil, firstErr
-}
-
-// containsDotDot reports whether s contains "..".
-func containsDotDot(s string) bool {
-	if len(s) < 2 {
-		return false
-	}
-	for i := 0; i < len(s)-1; i++ {
-		if s[i] == '.' && s[i+1] == '.' {
-			return true
-		}
-	}
-	return false
-}
diff --git a/contrib/go/_std_1.18/src/time/zoneinfo_read.go b/contrib/go/_std_1.18/src/time/zoneinfo_read.go
deleted file mode 100644
index b9830265e1..0000000000
--- a/contrib/go/_std_1.18/src/time/zoneinfo_read.go
+++ /dev/null
@@ -1,586 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Parse "zoneinfo" time zone file.
-// This is a fairly standard file format used on OS X, Linux, BSD, Sun, and others.
-// See tzfile(5), https://en.wikipedia.org/wiki/Zoneinfo,
-// and ftp://munnari.oz.au/pub/oldtz/
-
-package time
-
-import (
-	"errors"
-	"runtime"
-	"syscall"
-)
-
-// registerLoadFromEmbeddedTZData is called by the time/tzdata package,
-// if it is imported.
-func registerLoadFromEmbeddedTZData(f func(string) (string, error)) {
-	loadFromEmbeddedTZData = f
-}
-
-// loadFromEmbeddedTZData is used to load a specific tzdata file
-// from tzdata information embedded in the binary itself.
-// This is set when the time/tzdata package is imported,
-// via registerLoadFromEmbeddedTzdata.
-var loadFromEmbeddedTZData func(zipname string) (string, error)
-
-// maxFileSize is the max permitted size of files read by readFile.
-// As reference, the zoneinfo.zip distributed by Go is ~350 KB,
-// so 10MB is overkill.
-const maxFileSize = 10 << 20
-
-type fileSizeError string
-
-func (f fileSizeError) Error() string {
-	return "time: file " + string(f) + " is too large"
-}
-
-// Copies of io.Seek* constants to avoid importing "io":
-const (
-	seekStart   = 0
-	seekCurrent = 1
-	seekEnd     = 2
-)
-
-// Simple I/O interface to binary blob of data.
-type dataIO struct {
-	p     []byte
-	error bool
-}
-
-func (d *dataIO) read(n int) []byte {
-	if len(d.p) < n {
-		d.p = nil
-		d.error = true
-		return nil
-	}
-	p := d.p[0:n]
-	d.p = d.p[n:]
-	return p
-}
-
-func (d *dataIO) big4() (n uint32, ok bool) {
-	p := d.read(4)
-	if len(p) < 4 {
-		d.error = true
-		return 0, false
-	}
-	return uint32(p[3]) | uint32(p[2])<<8 | uint32(p[1])<<16 | uint32(p[0])<<24, true
-}
-
-func (d *dataIO) big8() (n uint64, ok bool) {
-	n1, ok1 := d.big4()
-	n2, ok2 := d.big4()
-	if !ok1 || !ok2 {
-		d.error = true
-		return 0, false
-	}
-	return (uint64(n1) << 32) | uint64(n2), true
-}
-
-func (d *dataIO) byte() (n byte, ok bool) {
-	p := d.read(1)
-	if len(p) < 1 {
-		d.error = true
-		return 0, false
-	}
-	return p[0], true
-}
-
-// read returns the read of the data in the buffer.
-func (d *dataIO) rest() []byte {
-	r := d.p
-	d.p = nil
-	return r
-}
-
-// Make a string by stopping at the first NUL
-func byteString(p []byte) string {
-	for i := 0; i < len(p); i++ {
-		if p[i] == 0 {
-			return string(p[0:i])
-		}
-	}
-	return string(p)
-}
-
-var badData = errors.New("malformed time zone information")
-
-// LoadLocationFromTZData returns a Location with the given name
-// initialized from the IANA Time Zone database-formatted data.
-// The data should be in the format of a standard IANA time zone file
-// (for example, the content of /etc/localtime on Unix systems).
-func LoadLocationFromTZData(name string, data []byte) (*Location, error) {
-	d := dataIO{data, false}
-
-	// 4-byte magic "TZif"
-	if magic := d.read(4); string(magic) != "TZif" {
-		return nil, badData
-	}
-
-	// 1-byte version, then 15 bytes of padding
-	var version int
-	var p []byte
-	if p = d.read(16); len(p) != 16 {
-		return nil, badData
-	} else {
-		switch p[0] {
-		case 0:
-			version = 1
-		case '2':
-			version = 2
-		case '3':
-			version = 3
-		default:
-			return nil, badData
-		}
-	}
-
-	// six big-endian 32-bit integers:
-	//	number of UTC/local indicators
-	//	number of standard/wall indicators
-	//	number of leap seconds
-	//	number of transition times
-	//	number of local time zones
-	//	number of characters of time zone abbrev strings
-	const (
-		NUTCLocal = iota
-		NStdWall
-		NLeap
-		NTime
-		NZone
-		NChar
-	)
-	var n [6]int
-	for i := 0; i < 6; i++ {
-		nn, ok := d.big4()
-		if !ok {
-			return nil, badData
-		}
-		if uint32(int(nn)) != nn {
-			return nil, badData
-		}
-		n[i] = int(nn)
-	}
-
-	// If we have version 2 or 3, then the data is first written out
-	// in a 32-bit format, then written out again in a 64-bit format.
-	// Skip the 32-bit format and read the 64-bit one, as it can
-	// describe a broader range of dates.
-
-	is64 := false
-	if version > 1 {
-		// Skip the 32-bit data.
-		skip := n[NTime]*4 +
-			n[NTime] +
-			n[NZone]*6 +
-			n[NChar] +
-			n[NLeap]*8 +
-			n[NStdWall] +
-			n[NUTCLocal]
-		// Skip the version 2 header that we just read.
-		skip += 4 + 16
-		d.read(skip)
-
-		is64 = true
-
-		// Read the counts again, they can differ.
-		for i := 0; i < 6; i++ {
-			nn, ok := d.big4()
-			if !ok {
-				return nil, badData
-			}
-			if uint32(int(nn)) != nn {
-				return nil, badData
-			}
-			n[i] = int(nn)
-		}
-	}
-
-	size := 4
-	if is64 {
-		size = 8
-	}
-
-	// Transition times.
-	txtimes := dataIO{d.read(n[NTime] * size), false}
-
-	// Time zone indices for transition times.
-	txzones := d.read(n[NTime])
-
-	// Zone info structures
-	zonedata := dataIO{d.read(n[NZone] * 6), false}
-
-	// Time zone abbreviations.
-	abbrev := d.read(n[NChar])
-
-	// Leap-second time pairs
-	d.read(n[NLeap] * (size + 4))
-
-	// Whether tx times associated with local time types
-	// are specified as standard time or wall time.
-	isstd := d.read(n[NStdWall])
-
-	// Whether tx times associated with local time types
-	// are specified as UTC or local time.
-	isutc := d.read(n[NUTCLocal])
-
-	if d.error { // ran out of data
-		return nil, badData
-	}
-
-	var extend string
-	rest := d.rest()
-	if len(rest) > 2 && rest[0] == '\n' && rest[len(rest)-1] == '\n' {
-		extend = string(rest[1 : len(rest)-1])
-	}
-
-	// Now we can build up a useful data structure.
-	// First the zone information.
-	//	utcoff[4] isdst[1] nameindex[1]
-	nzone := n[NZone]
-	if nzone == 0 {
-		// Reject tzdata files with no zones. There's nothing useful in them.
-		// This also avoids a panic later when we add and then use a fake transition (golang.org/issue/29437).
-		return nil, badData
-	}
-	zones := make([]zone, nzone)
-	for i := range zones {
-		var ok bool
-		var n uint32
-		if n, ok = zonedata.big4(); !ok {
-			return nil, badData
-		}
-		if uint32(int(n)) != n {
-			return nil, badData
-		}
-		zones[i].offset = int(int32(n))
-		var b byte
-		if b, ok = zonedata.byte(); !ok {
-			return nil, badData
-		}
-		zones[i].isDST = b != 0
-		if b, ok = zonedata.byte(); !ok || int(b) >= len(abbrev) {
-			return nil, badData
-		}
-		zones[i].name = byteString(abbrev[b:])
-		if runtime.GOOS == "aix" && len(name) > 8 && (name[:8] == "Etc/GMT+" || name[:8] == "Etc/GMT-") {
-			// There is a bug with AIX 7.2 TL 0 with files in Etc,
-			// GMT+1 will return GMT-1 instead of GMT+1 or -01.
-			if name != "Etc/GMT+0" {
-				// GMT+0 is OK
-				zones[i].name = name[4:]
-			}
-		}
-	}
-
-	// Now the transition time info.
-	tx := make([]zoneTrans, n[NTime])
-	for i := range tx {
-		var n int64
-		if !is64 {
-			if n4, ok := txtimes.big4(); !ok {
-				return nil, badData
-			} else {
-				n = int64(int32(n4))
-			}
-		} else {
-			if n8, ok := txtimes.big8(); !ok {
-				return nil, badData
-			} else {
-				n = int64(n8)
-			}
-		}
-		tx[i].when = n
-		if int(txzones[i]) >= len(zones) {
-			return nil, badData
-		}
-		tx[i].index = txzones[i]
-		if i < len(isstd) {
-			tx[i].isstd = isstd[i] != 0
-		}
-		if i < len(isutc) {
-			tx[i].isutc = isutc[i] != 0
-		}
-	}
-
-	if len(tx) == 0 {
-		// Build fake transition to cover all time.
-		// This happens in fixed locations like "Etc/GMT0".
-		tx = append(tx, zoneTrans{when: alpha, index: 0})
-	}
-
-	// Committed to succeed.
-	l := &Location{zone: zones, tx: tx, name: name, extend: extend}
-
-	// Fill in the cache with information about right now,
-	// since that will be the most common lookup.
-	sec, _, _ := now()
-	for i := range tx {
-		if tx[i].when <= sec && (i+1 == len(tx) || sec < tx[i+1].when) {
-			l.cacheStart = tx[i].when
-			l.cacheEnd = omega
-			l.cacheZone = &l.zone[tx[i].index]
-			if i+1 < len(tx) {
-				l.cacheEnd = tx[i+1].when
-			} else if l.extend != "" {
-				// If we're at the end of the known zone transitions,
-				// try the extend string.
-				if name, offset, estart, eend, isDST, ok := tzset(l.extend, l.cacheEnd, sec); ok {
-					l.cacheStart = estart
-					l.cacheEnd = eend
-					// Find the zone that is returned by tzset to avoid allocation if possible.
-					if zoneIdx := findZone(l.zone, name, offset, isDST); zoneIdx != -1 {
-						l.cacheZone = &l.zone[zoneIdx]
-					} else {
-						l.cacheZone = &zone{
-							name:   name,
-							offset: offset,
-							isDST:  isDST,
-						}
-					}
-				}
-			}
-			break
-		}
-	}
-
-	return l, nil
-}
-
-func findZone(zones []zone, name string, offset int, isDST bool) int {
-	for i, z := range zones {
-		if z.name == name && z.offset == offset && z.isDST == isDST {
-			return i
-		}
-	}
-	return -1
-}
-
-// loadTzinfoFromDirOrZip returns the contents of the file with the given name
-// in dir. dir can either be an uncompressed zip file, or a directory.
-func loadTzinfoFromDirOrZip(dir, name string) ([]byte, error) {
-	if len(dir) > 4 && dir[len(dir)-4:] == ".zip" {
-		return loadTzinfoFromZip(dir, name)
-	}
-	if dir != "" {
-		name = dir + "/" + name
-	}
-	return readFile(name)
-}
-
-// There are 500+ zoneinfo files. Rather than distribute them all
-// individually, we ship them in an uncompressed zip file.
-// Used this way, the zip file format serves as a commonly readable
-// container for the individual small files. We choose zip over tar
-// because zip files have a contiguous table of contents, making
-// individual file lookups faster, and because the per-file overhead
-// in a zip file is considerably less than tar's 512 bytes.
-
-// get4 returns the little-endian 32-bit value in b.
-func get4(b []byte) int {
-	if len(b) < 4 {
-		return 0
-	}
-	return int(b[0]) | int(b[1])<<8 | int(b[2])<<16 | int(b[3])<<24
-}
-
-// get2 returns the little-endian 16-bit value in b.
-func get2(b []byte) int {
-	if len(b) < 2 {
-		return 0
-	}
-	return int(b[0]) | int(b[1])<<8
-}
-
-// loadTzinfoFromZip returns the contents of the file with the given name
-// in the given uncompressed zip file.
-func loadTzinfoFromZip(zipfile, name string) ([]byte, error) {
-	fd, err := open(zipfile)
-	if err != nil {
-		return nil, err
-	}
-	defer closefd(fd)
-
-	const (
-		zecheader = 0x06054b50
-		zcheader  = 0x02014b50
-		ztailsize = 22
-
-		zheadersize = 30
-		zheader     = 0x04034b50
-	)
-
-	buf := make([]byte, ztailsize)
-	if err := preadn(fd, buf, -ztailsize); err != nil || get4(buf) != zecheader {
-		return nil, errors.New("corrupt zip file " + zipfile)
-	}
-	n := get2(buf[10:])
-	size := get4(buf[12:])
-	off := get4(buf[16:])
-
-	buf = make([]byte, size)
-	if err := preadn(fd, buf, off); err != nil {
-		return nil, errors.New("corrupt zip file " + zipfile)
-	}
-
-	for i := 0; i < n; i++ {
-		// zip entry layout:
-		//	0	magic[4]
-		//	4	madevers[1]
-		//	5	madeos[1]
-		//	6	extvers[1]
-		//	7	extos[1]
-		//	8	flags[2]
-		//	10	meth[2]
-		//	12	modtime[2]
-		//	14	moddate[2]
-		//	16	crc[4]
-		//	20	csize[4]
-		//	24	uncsize[4]
-		//	28	namelen[2]
-		//	30	xlen[2]
-		//	32	fclen[2]
-		//	34	disknum[2]
-		//	36	iattr[2]
-		//	38	eattr[4]
-		//	42	off[4]
-		//	46	name[namelen]
-		//	46+namelen+xlen+fclen - next header
-		//
-		if get4(buf) != zcheader {
-			break
-		}
-		meth := get2(buf[10:])
-		size := get4(buf[24:])
-		namelen := get2(buf[28:])
-		xlen := get2(buf[30:])
-		fclen := get2(buf[32:])
-		off := get4(buf[42:])
-		zname := buf[46 : 46+namelen]
-		buf = buf[46+namelen+xlen+fclen:]
-		if string(zname) != name {
-			continue
-		}
-		if meth != 0 {
-			return nil, errors.New("unsupported compression for " + name + " in " + zipfile)
-		}
-
-		// zip per-file header layout:
-		//	0	magic[4]
-		//	4	extvers[1]
-		//	5	extos[1]
-		//	6	flags[2]
-		//	8	meth[2]
-		//	10	modtime[2]
-		//	12	moddate[2]
-		//	14	crc[4]
-		//	18	csize[4]
-		//	22	uncsize[4]
-		//	26	namelen[2]
-		//	28	xlen[2]
-		//	30	name[namelen]
-		//	30+namelen+xlen - file data
-		//
-		buf = make([]byte, zheadersize+namelen)
-		if err := preadn(fd, buf, off); err != nil ||
-			get4(buf) != zheader ||
-			get2(buf[8:]) != meth ||
-			get2(buf[26:]) != namelen ||
-			string(buf[30:30+namelen]) != name {
-			return nil, errors.New("corrupt zip file " + zipfile)
-		}
-		xlen = get2(buf[28:])
-
-		buf = make([]byte, size)
-		if err := preadn(fd, buf, off+30+namelen+xlen); err != nil {
-			return nil, errors.New("corrupt zip file " + zipfile)
-		}
-
-		return buf, nil
-	}
-
-	return nil, syscall.ENOENT
-}
-
-// loadTzinfoFromTzdata returns the time zone information of the time zone
-// with the given name, from a tzdata database file as they are typically
-// found on android.
-var loadTzinfoFromTzdata func(file, name string) ([]byte, error)
-
-// loadTzinfo returns the time zone information of the time zone
-// with the given name, from a given source. A source may be a
-// timezone database directory, tzdata database file or an uncompressed
-// zip file, containing the contents of such a directory.
-func loadTzinfo(name string, source string) ([]byte, error) {
-	if len(source) >= 6 && source[len(source)-6:] == "tzdata" {
-		return loadTzinfoFromTzdata(source, name)
-	}
-	return loadTzinfoFromDirOrZip(source, name)
-}
-
-// loadLocation returns the Location with the given name from one of
-// the specified sources. See loadTzinfo for a list of supported sources.
-// The first timezone data matching the given name that is successfully loaded
-// and parsed is returned as a Location.
-func loadLocation(name string, sources []string) (z *Location, firstErr error) {
-	for _, source := range sources {
-		var zoneData, err = loadTzinfo(name, source)
-		if err == nil {
-			if z, err = LoadLocationFromTZData(name, zoneData); err == nil {
-				return z, nil
-			}
-		}
-		if firstErr == nil && err != syscall.ENOENT {
-			firstErr = err
-		}
-	}
-	if loadFromEmbeddedTZData != nil {
-		zonedata, err := loadFromEmbeddedTZData(name)
-		if err == nil {
-			if z, err = LoadLocationFromTZData(name, []byte(zonedata)); err == nil {
-				return z, nil
-			}
-		}
-		if firstErr == nil && err != syscall.ENOENT {
-			firstErr = err
-		}
-	}
-	if firstErr != nil {
-		return nil, firstErr
-	}
-	return nil, errors.New("unknown time zone " + name)
-}
-
-// readFile reads and returns the content of the named file.
-// It is a trivial implementation of os.ReadFile, reimplemented
-// here to avoid depending on io/ioutil or os.
-// It returns an error if name exceeds maxFileSize bytes.
-func readFile(name string) ([]byte, error) {
-	f, err := open(name)
-	if err != nil {
-		return nil, err
-	}
-	defer closefd(f)
-	var (
-		buf [4096]byte
-		ret []byte
-		n   int
-	)
-	for {
-		n, err = read(f, buf[:])
-		if n > 0 {
-			ret = append(ret, buf[:n]...)
-		}
-		if n == 0 || err != nil {
-			break
-		}
-		if len(ret) > maxFileSize {
-			return nil, fileSizeError(name)
-		}
-	}
-	return ret, err
-}
diff --git a/contrib/go/_std_1.18/src/time/zoneinfo_unix.go b/contrib/go/_std_1.18/src/time/zoneinfo_unix.go
deleted file mode 100644
index 23f8b3cdb4..0000000000
--- a/contrib/go/_std_1.18/src/time/zoneinfo_unix.go
+++ /dev/null
@@ -1,69 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build aix || (darwin && !ios) || dragonfly || freebsd || (linux && !android) || netbsd || openbsd || solaris
-
-// Parse "zoneinfo" time zone file.
-// This is a fairly standard file format used on OS X, Linux, BSD, Sun, and others.
-// See tzfile(5), https://en.wikipedia.org/wiki/Zoneinfo,
-// and ftp://munnari.oz.au/pub/oldtz/
-
-package time
-
-import (
-	"runtime"
-	"syscall"
-)
-
-// Many systems use /usr/share/zoneinfo, Solaris 2 has
-// /usr/share/lib/zoneinfo, IRIX 6 has /usr/lib/locale/TZ.
-var zoneSources = []string{
-	"/usr/share/zoneinfo/",
-	"/usr/share/lib/zoneinfo/",
-	"/usr/lib/locale/TZ/",
-	runtime.GOROOT() + "/lib/time/zoneinfo.zip",
-}
-
-func initLocal() {
-	// consult $TZ to find the time zone to use.
-	// no $TZ means use the system default /etc/localtime.
-	// $TZ="" means use UTC.
-	// $TZ="foo" or $TZ=":foo" if foo is an absolute path, then the file pointed
-	// by foo will be used to initialize timezone; otherwise, file
-	// /usr/share/zoneinfo/foo will be used.
-
-	tz, ok := syscall.Getenv("TZ")
-	switch {
-	case !ok:
-		z, err := loadLocation("localtime", []string{"/etc"})
-		if err == nil {
-			localLoc = *z
-			localLoc.name = "Local"
-			return
-		}
-	case tz != "":
-		if tz[0] == ':' {
-			tz = tz[1:]
-		}
-		if tz != "" && tz[0] == '/' {
-			if z, err := loadLocation(tz, []string{""}); err == nil {
-				localLoc = *z
-				if tz == "/etc/localtime" {
-					localLoc.name = "Local"
-				} else {
-					localLoc.name = tz
-				}
-				return
-			}
-		} else if tz != "" && tz != "UTC" {
-			if z, err := loadLocation(tz, zoneSources); err == nil {
-				localLoc = *z
-				return
-			}
-		}
-	}
-
-	// Fall back to UTC.
-	localLoc.name = "UTC"
-}
diff --git a/contrib/go/_std_1.18/src/unicode/graphic.go b/contrib/go/_std_1.18/src/unicode/graphic.go
deleted file mode 100644
index ca6241949a..0000000000
--- a/contrib/go/_std_1.18/src/unicode/graphic.go
+++ /dev/null
@@ -1,144 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package unicode
-
-// Bit masks for each code point under U+0100, for fast lookup.
-const (
-	pC     = 1 << iota // a control character.
-	pP                 // a punctuation character.
-	pN                 // a numeral.
-	pS                 // a symbolic character.
-	pZ                 // a spacing character.
-	pLu                // an upper-case letter.
-	pLl                // a lower-case letter.
-	pp                 // a printable character according to Go's definition.
-	pg     = pp | pZ   // a graphical character according to the Unicode definition.
-	pLo    = pLl | pLu // a letter that is neither upper nor lower case.
-	pLmask = pLo
-)
-
-// GraphicRanges defines the set of graphic characters according to Unicode.
-var GraphicRanges = []*RangeTable{
-	L, M, N, P, S, Zs,
-}
-
-// PrintRanges defines the set of printable characters according to Go.
-// ASCII space, U+0020, is handled separately.
-var PrintRanges = []*RangeTable{
-	L, M, N, P, S,
-}
-
-// IsGraphic reports whether the rune is defined as a Graphic by Unicode.
-// Such characters include letters, marks, numbers, punctuation, symbols, and
-// spaces, from categories L, M, N, P, S, Zs.
-func IsGraphic(r rune) bool {
-	// We convert to uint32 to avoid the extra test for negative,
-	// and in the index we convert to uint8 to avoid the range check.
-	if uint32(r) <= MaxLatin1 {
-		return properties[uint8(r)]&pg != 0
-	}
-	return In(r, GraphicRanges...)
-}
-
-// IsPrint reports whether the rune is defined as printable by Go. Such
-// characters include letters, marks, numbers, punctuation, symbols, and the
-// ASCII space character, from categories L, M, N, P, S and the ASCII space
-// character. This categorization is the same as IsGraphic except that the
-// only spacing character is ASCII space, U+0020.
-func IsPrint(r rune) bool {
-	if uint32(r) <= MaxLatin1 {
-		return properties[uint8(r)]&pp != 0
-	}
-	return In(r, PrintRanges...)
-}
-
-// IsOneOf reports whether the rune is a member of one of the ranges.
-// The function "In" provides a nicer signature and should be used in preference to IsOneOf.
-func IsOneOf(ranges []*RangeTable, r rune) bool {
-	for _, inside := range ranges {
-		if Is(inside, r) {
-			return true
-		}
-	}
-	return false
-}
-
-// In reports whether the rune is a member of one of the ranges.
-func In(r rune, ranges ...*RangeTable) bool {
-	for _, inside := range ranges {
-		if Is(inside, r) {
-			return true
-		}
-	}
-	return false
-}
-
-// IsControl reports whether the rune is a control character.
-// The C (Other) Unicode category includes more code points
-// such as surrogates; use Is(C, r) to test for them.
-func IsControl(r rune) bool {
-	if uint32(r) <= MaxLatin1 {
-		return properties[uint8(r)]&pC != 0
-	}
-	// All control characters are < MaxLatin1.
-	return false
-}
-
-// IsLetter reports whether the rune is a letter (category L).
-func IsLetter(r rune) bool {
-	if uint32(r) <= MaxLatin1 {
-		return properties[uint8(r)]&(pLmask) != 0
-	}
-	return isExcludingLatin(Letter, r)
-}
-
-// IsMark reports whether the rune is a mark character (category M).
-func IsMark(r rune) bool {
-	// There are no mark characters in Latin-1.
-	return isExcludingLatin(Mark, r)
-}
-
-// IsNumber reports whether the rune is a number (category N).
-func IsNumber(r rune) bool {
-	if uint32(r) <= MaxLatin1 {
-		return properties[uint8(r)]&pN != 0
-	}
-	return isExcludingLatin(Number, r)
-}
-
-// IsPunct reports whether the rune is a Unicode punctuation character
-// (category P).
-func IsPunct(r rune) bool {
-	if uint32(r) <= MaxLatin1 {
-		return properties[uint8(r)]&pP != 0
-	}
-	return Is(Punct, r)
-}
-
-// IsSpace reports whether the rune is a space character as defined
-// by Unicode's White Space property; in the Latin-1 space
-// this is
-//	'\t', '\n', '\v', '\f', '\r', ' ', U+0085 (NEL), U+00A0 (NBSP).
-// Other definitions of spacing characters are set by category
-// Z and property Pattern_White_Space.
-func IsSpace(r rune) bool {
-	// This property isn't the same as Z; special-case it.
-	if uint32(r) <= MaxLatin1 {
-		switch r {
-		case '\t', '\n', '\v', '\f', '\r', ' ', 0x85, 0xA0:
-			return true
-		}
-		return false
-	}
-	return isExcludingLatin(White_Space, r)
-}
-
-// IsSymbol reports whether the rune is a symbolic character.
-func IsSymbol(r rune) bool {
-	if uint32(r) <= MaxLatin1 {
-		return properties[uint8(r)]&pS != 0
-	}
-	return isExcludingLatin(Symbol, r)
-}
diff --git a/contrib/go/_std_1.18/src/unicode/letter.go b/contrib/go/_std_1.18/src/unicode/letter.go
deleted file mode 100644
index 268e457a87..0000000000
--- a/contrib/go/_std_1.18/src/unicode/letter.go
+++ /dev/null
@@ -1,369 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package unicode provides data and functions to test some properties of
-// Unicode code points.
-package unicode
-
-const (
-	MaxRune         = '\U0010FFFF' // Maximum valid Unicode code point.
-	ReplacementChar = '\uFFFD'     // Represents invalid code points.
-	MaxASCII        = '\u007F'     // maximum ASCII value.
-	MaxLatin1       = '\u00FF'     // maximum Latin-1 value.
-)
-
-// RangeTable defines a set of Unicode code points by listing the ranges of
-// code points within the set. The ranges are listed in two slices
-// to save space: a slice of 16-bit ranges and a slice of 32-bit ranges.
-// The two slices must be in sorted order and non-overlapping.
-// Also, R32 should contain only values >= 0x10000 (1<<16).
-type RangeTable struct {
-	R16         []Range16
-	R32         []Range32
-	LatinOffset int // number of entries in R16 with Hi <= MaxLatin1
-}
-
-// Range16 represents of a range of 16-bit Unicode code points. The range runs from Lo to Hi
-// inclusive and has the specified stride.
-type Range16 struct {
-	Lo     uint16
-	Hi     uint16
-	Stride uint16
-}
-
-// Range32 represents of a range of Unicode code points and is used when one or
-// more of the values will not fit in 16 bits. The range runs from Lo to Hi
-// inclusive and has the specified stride. Lo and Hi must always be >= 1<<16.
-type Range32 struct {
-	Lo     uint32
-	Hi     uint32
-	Stride uint32
-}
-
-// CaseRange represents a range of Unicode code points for simple (one
-// code point to one code point) case conversion.
-// The range runs from Lo to Hi inclusive, with a fixed stride of 1. Deltas
-// are the number to add to the code point to reach the code point for a
-// different case for that character. They may be negative. If zero, it
-// means the character is in the corresponding case. There is a special
-// case representing sequences of alternating corresponding Upper and Lower
-// pairs. It appears with a fixed Delta of
-//	{UpperLower, UpperLower, UpperLower}
-// The constant UpperLower has an otherwise impossible delta value.
-type CaseRange struct {
-	Lo    uint32
-	Hi    uint32
-	Delta d
-}
-
-// SpecialCase represents language-specific case mappings such as Turkish.
-// Methods of SpecialCase customize (by overriding) the standard mappings.
-type SpecialCase []CaseRange
-
-// BUG(r): There is no mechanism for full case folding, that is, for
-// characters that involve multiple runes in the input or output.
-
-// Indices into the Delta arrays inside CaseRanges for case mapping.
-const (
-	UpperCase = iota
-	LowerCase
-	TitleCase
-	MaxCase
-)
-
-type d [MaxCase]rune // to make the CaseRanges text shorter
-
-// If the Delta field of a CaseRange is UpperLower, it means
-// this CaseRange represents a sequence of the form (say)
-// Upper Lower Upper Lower.
-const (
-	UpperLower = MaxRune + 1 // (Cannot be a valid delta.)
-)
-
-// linearMax is the maximum size table for linear search for non-Latin1 rune.
-// Derived by running 'go test -calibrate'.
-const linearMax = 18
-
-// is16 reports whether r is in the sorted slice of 16-bit ranges.
-func is16(ranges []Range16, r uint16) bool {
-	if len(ranges) <= linearMax || r <= MaxLatin1 {
-		for i := range ranges {
-			range_ := &ranges[i]
-			if r < range_.Lo {
-				return false
-			}
-			if r <= range_.Hi {
-				return range_.Stride == 1 || (r-range_.Lo)%range_.Stride == 0
-			}
-		}
-		return false
-	}
-
-	// binary search over ranges
-	lo := 0
-	hi := len(ranges)
-	for lo < hi {
-		m := lo + (hi-lo)/2
-		range_ := &ranges[m]
-		if range_.Lo <= r && r <= range_.Hi {
-			return range_.Stride == 1 || (r-range_.Lo)%range_.Stride == 0
-		}
-		if r < range_.Lo {
-			hi = m
-		} else {
-			lo = m + 1
-		}
-	}
-	return false
-}
-
-// is32 reports whether r is in the sorted slice of 32-bit ranges.
-func is32(ranges []Range32, r uint32) bool {
-	if len(ranges) <= linearMax {
-		for i := range ranges {
-			range_ := &ranges[i]
-			if r < range_.Lo {
-				return false
-			}
-			if r <= range_.Hi {
-				return range_.Stride == 1 || (r-range_.Lo)%range_.Stride == 0
-			}
-		}
-		return false
-	}
-
-	// binary search over ranges
-	lo := 0
-	hi := len(ranges)
-	for lo < hi {
-		m := lo + (hi-lo)/2
-		range_ := ranges[m]
-		if range_.Lo <= r && r <= range_.Hi {
-			return range_.Stride == 1 || (r-range_.Lo)%range_.Stride == 0
-		}
-		if r < range_.Lo {
-			hi = m
-		} else {
-			lo = m + 1
-		}
-	}
-	return false
-}
-
-// Is reports whether the rune is in the specified table of ranges.
-func Is(rangeTab *RangeTable, r rune) bool {
-	r16 := rangeTab.R16
-	// Compare as uint32 to correctly handle negative runes.
-	if len(r16) > 0 && uint32(r) <= uint32(r16[len(r16)-1].Hi) {
-		return is16(r16, uint16(r))
-	}
-	r32 := rangeTab.R32
-	if len(r32) > 0 && r >= rune(r32[0].Lo) {
-		return is32(r32, uint32(r))
-	}
-	return false
-}
-
-func isExcludingLatin(rangeTab *RangeTable, r rune) bool {
-	r16 := rangeTab.R16
-	// Compare as uint32 to correctly handle negative runes.
-	if off := rangeTab.LatinOffset; len(r16) > off && uint32(r) <= uint32(r16[len(r16)-1].Hi) {
-		return is16(r16[off:], uint16(r))
-	}
-	r32 := rangeTab.R32
-	if len(r32) > 0 && r >= rune(r32[0].Lo) {
-		return is32(r32, uint32(r))
-	}
-	return false
-}
-
-// IsUpper reports whether the rune is an upper case letter.
-func IsUpper(r rune) bool {
-	// See comment in IsGraphic.
-	if uint32(r) <= MaxLatin1 {
-		return properties[uint8(r)]&pLmask == pLu
-	}
-	return isExcludingLatin(Upper, r)
-}
-
-// IsLower reports whether the rune is a lower case letter.
-func IsLower(r rune) bool {
-	// See comment in IsGraphic.
-	if uint32(r) <= MaxLatin1 {
-		return properties[uint8(r)]&pLmask == pLl
-	}
-	return isExcludingLatin(Lower, r)
-}
-
-// IsTitle reports whether the rune is a title case letter.
-func IsTitle(r rune) bool {
-	if r <= MaxLatin1 {
-		return false
-	}
-	return isExcludingLatin(Title, r)
-}
-
-// to maps the rune using the specified case mapping.
-// It additionally reports whether caseRange contained a mapping for r.
-func to(_case int, r rune, caseRange []CaseRange) (mappedRune rune, foundMapping bool) {
-	if _case < 0 || MaxCase <= _case {
-		return ReplacementChar, false // as reasonable an error as any
-	}
-	// binary search over ranges
-	lo := 0
-	hi := len(caseRange)
-	for lo < hi {
-		m := lo + (hi-lo)/2
-		cr := caseRange[m]
-		if rune(cr.Lo) <= r && r <= rune(cr.Hi) {
-			delta := cr.Delta[_case]
-			if delta > MaxRune {
-				// In an Upper-Lower sequence, which always starts with
-				// an UpperCase letter, the real deltas always look like:
-				//	{0, 1, 0}    UpperCase (Lower is next)
-				//	{-1, 0, -1}  LowerCase (Upper, Title are previous)
-				// The characters at even offsets from the beginning of the
-				// sequence are upper case; the ones at odd offsets are lower.
-				// The correct mapping can be done by clearing or setting the low
-				// bit in the sequence offset.
-				// The constants UpperCase and TitleCase are even while LowerCase
-				// is odd so we take the low bit from _case.
-				return rune(cr.Lo) + ((r-rune(cr.Lo))&^1 | rune(_case&1)), true
-			}
-			return r + delta, true
-		}
-		if r < rune(cr.Lo) {
-			hi = m
-		} else {
-			lo = m + 1
-		}
-	}
-	return r, false
-}
-
-// To maps the rune to the specified case: UpperCase, LowerCase, or TitleCase.
-func To(_case int, r rune) rune {
-	r, _ = to(_case, r, CaseRanges)
-	return r
-}
-
-// ToUpper maps the rune to upper case.
-func ToUpper(r rune) rune {
-	if r <= MaxASCII {
-		if 'a' <= r && r <= 'z' {
-			r -= 'a' - 'A'
-		}
-		return r
-	}
-	return To(UpperCase, r)
-}
-
-// ToLower maps the rune to lower case.
-func ToLower(r rune) rune {
-	if r <= MaxASCII {
-		if 'A' <= r && r <= 'Z' {
-			r += 'a' - 'A'
-		}
-		return r
-	}
-	return To(LowerCase, r)
-}
-
-// ToTitle maps the rune to title case.
-func ToTitle(r rune) rune {
-	if r <= MaxASCII {
-		if 'a' <= r && r <= 'z' { // title case is upper case for ASCII
-			r -= 'a' - 'A'
-		}
-		return r
-	}
-	return To(TitleCase, r)
-}
-
-// ToUpper maps the rune to upper case giving priority to the special mapping.
-func (special SpecialCase) ToUpper(r rune) rune {
-	r1, hadMapping := to(UpperCase, r, []CaseRange(special))
-	if r1 == r && !hadMapping {
-		r1 = ToUpper(r)
-	}
-	return r1
-}
-
-// ToTitle maps the rune to title case giving priority to the special mapping.
-func (special SpecialCase) ToTitle(r rune) rune {
-	r1, hadMapping := to(TitleCase, r, []CaseRange(special))
-	if r1 == r && !hadMapping {
-		r1 = ToTitle(r)
-	}
-	return r1
-}
-
-// ToLower maps the rune to lower case giving priority to the special mapping.
-func (special SpecialCase) ToLower(r rune) rune {
-	r1, hadMapping := to(LowerCase, r, []CaseRange(special))
-	if r1 == r && !hadMapping {
-		r1 = ToLower(r)
-	}
-	return r1
-}
-
-// caseOrbit is defined in tables.go as []foldPair. Right now all the
-// entries fit in uint16, so use uint16. If that changes, compilation
-// will fail (the constants in the composite literal will not fit in uint16)
-// and the types here can change to uint32.
-type foldPair struct {
-	From uint16
-	To   uint16
-}
-
-// SimpleFold iterates over Unicode code points equivalent under
-// the Unicode-defined simple case folding. Among the code points
-// equivalent to rune (including rune itself), SimpleFold returns the
-// smallest rune > r if one exists, or else the smallest rune >= 0.
-// If r is not a valid Unicode code point, SimpleFold(r) returns r.
-//
-// For example:
-//	SimpleFold('A') = 'a'
-//	SimpleFold('a') = 'A'
-//
-//	SimpleFold('K') = 'k'
-//	SimpleFold('k') = '\u212A' (Kelvin symbol, K)
-//	SimpleFold('\u212A') = 'K'
-//
-//	SimpleFold('1') = '1'
-//
-//	SimpleFold(-2) = -2
-//
-func SimpleFold(r rune) rune {
-	if r < 0 || r > MaxRune {
-		return r
-	}
-
-	if int(r) < len(asciiFold) {
-		return rune(asciiFold[r])
-	}
-
-	// Consult caseOrbit table for special cases.
-	lo := 0
-	hi := len(caseOrbit)
-	for lo < hi {
-		m := lo + (hi-lo)/2
-		if rune(caseOrbit[m].From) < r {
-			lo = m + 1
-		} else {
-			hi = m
-		}
-	}
-	if lo < len(caseOrbit) && rune(caseOrbit[lo].From) == r {
-		return rune(caseOrbit[lo].To)
-	}
-
-	// No folding specified. This is a one- or two-element
-	// equivalence class containing rune and ToLower(rune)
-	// and ToUpper(rune) if they are different from rune.
-	if l := ToLower(r); l != r {
-		return l
-	}
-	return ToUpper(r)
-}
diff --git a/contrib/go/_std_1.18/src/unicode/utf8/utf8.go b/contrib/go/_std_1.18/src/unicode/utf8/utf8.go
deleted file mode 100644
index 6938c7e6a7..0000000000
--- a/contrib/go/_std_1.18/src/unicode/utf8/utf8.go
+++ /dev/null
@@ -1,578 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package utf8 implements functions and constants to support text encoded in
-// UTF-8. It includes functions to translate between runes and UTF-8 byte sequences.
-// See https://en.wikipedia.org/wiki/UTF-8
-package utf8
-
-// The conditions RuneError==unicode.ReplacementChar and
-// MaxRune==unicode.MaxRune are verified in the tests.
-// Defining them locally avoids this package depending on package unicode.
-
-// Numbers fundamental to the encoding.
-const (
-	RuneError = '\uFFFD'     // the "error" Rune or "Unicode replacement character"
-	RuneSelf  = 0x80         // characters below RuneSelf are represented as themselves in a single byte.
-	MaxRune   = '\U0010FFFF' // Maximum valid Unicode code point.
-	UTFMax    = 4            // maximum number of bytes of a UTF-8 encoded Unicode character.
-)
-
-// Code points in the surrogate range are not valid for UTF-8.
-const (
-	surrogateMin = 0xD800
-	surrogateMax = 0xDFFF
-)
-
-const (
-	t1 = 0b00000000
-	tx = 0b10000000
-	t2 = 0b11000000
-	t3 = 0b11100000
-	t4 = 0b11110000
-	t5 = 0b11111000
-
-	maskx = 0b00111111
-	mask2 = 0b00011111
-	mask3 = 0b00001111
-	mask4 = 0b00000111
-
-	rune1Max = 1<<7 - 1
-	rune2Max = 1<<11 - 1
-	rune3Max = 1<<16 - 1
-
-	// The default lowest and highest continuation byte.
-	locb = 0b10000000
-	hicb = 0b10111111
-
-	// These names of these constants are chosen to give nice alignment in the
-	// table below. The first nibble is an index into acceptRanges or F for
-	// special one-byte cases. The second nibble is the Rune length or the
-	// Status for the special one-byte case.
-	xx = 0xF1 // invalid: size 1
-	as = 0xF0 // ASCII: size 1
-	s1 = 0x02 // accept 0, size 2
-	s2 = 0x13 // accept 1, size 3
-	s3 = 0x03 // accept 0, size 3
-	s4 = 0x23 // accept 2, size 3
-	s5 = 0x34 // accept 3, size 4
-	s6 = 0x04 // accept 0, size 4
-	s7 = 0x44 // accept 4, size 4
-)
-
-// first is information about the first byte in a UTF-8 sequence.
-var first = [256]uint8{
-	//   1   2   3   4   5   6   7   8   9   A   B   C   D   E   F
-	as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, // 0x00-0x0F
-	as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, // 0x10-0x1F
-	as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, // 0x20-0x2F
-	as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, // 0x30-0x3F
-	as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, // 0x40-0x4F
-	as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, // 0x50-0x5F
-	as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, // 0x60-0x6F
-	as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, // 0x70-0x7F
-	//   1   2   3   4   5   6   7   8   9   A   B   C   D   E   F
-	xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, // 0x80-0x8F
-	xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, // 0x90-0x9F
-	xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, // 0xA0-0xAF
-	xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, // 0xB0-0xBF
-	xx, xx, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, // 0xC0-0xCF
-	s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, // 0xD0-0xDF
-	s2, s3, s3, s3, s3, s3, s3, s3, s3, s3, s3, s3, s3, s4, s3, s3, // 0xE0-0xEF
-	s5, s6, s6, s6, s7, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, // 0xF0-0xFF
-}
-
-// acceptRange gives the range of valid values for the second byte in a UTF-8
-// sequence.
-type acceptRange struct {
-	lo uint8 // lowest value for second byte.
-	hi uint8 // highest value for second byte.
-}
-
-// acceptRanges has size 16 to avoid bounds checks in the code that uses it.
-var acceptRanges = [16]acceptRange{
-	0: {locb, hicb},
-	1: {0xA0, hicb},
-	2: {locb, 0x9F},
-	3: {0x90, hicb},
-	4: {locb, 0x8F},
-}
-
-// FullRune reports whether the bytes in p begin with a full UTF-8 encoding of a rune.
-// An invalid encoding is considered a full Rune since it will convert as a width-1 error rune.
-func FullRune(p []byte) bool {
-	n := len(p)
-	if n == 0 {
-		return false
-	}
-	x := first[p[0]]
-	if n >= int(x&7) {
-		return true // ASCII, invalid or valid.
-	}
-	// Must be short or invalid.
-	accept := acceptRanges[x>>4]
-	if n > 1 && (p[1] < accept.lo || accept.hi < p[1]) {
-		return true
-	} else if n > 2 && (p[2] < locb || hicb < p[2]) {
-		return true
-	}
-	return false
-}
-
-// FullRuneInString is like FullRune but its input is a string.
-func FullRuneInString(s string) bool {
-	n := len(s)
-	if n == 0 {
-		return false
-	}
-	x := first[s[0]]
-	if n >= int(x&7) {
-		return true // ASCII, invalid, or valid.
-	}
-	// Must be short or invalid.
-	accept := acceptRanges[x>>4]
-	if n > 1 && (s[1] < accept.lo || accept.hi < s[1]) {
-		return true
-	} else if n > 2 && (s[2] < locb || hicb < s[2]) {
-		return true
-	}
-	return false
-}
-
-// DecodeRune unpacks the first UTF-8 encoding in p and returns the rune and
-// its width in bytes. If p is empty it returns (RuneError, 0). Otherwise, if
-// the encoding is invalid, it returns (RuneError, 1). Both are impossible
-// results for correct, non-empty UTF-8.
-//
-// An encoding is invalid if it is incorrect UTF-8, encodes a rune that is
-// out of range, or is not the shortest possible UTF-8 encoding for the
-// value. No other validation is performed.
-func DecodeRune(p []byte) (r rune, size int) {
-	n := len(p)
-	if n < 1 {
-		return RuneError, 0
-	}
-	p0 := p[0]
-	x := first[p0]
-	if x >= as {
-		// The following code simulates an additional check for x == xx and
-		// handling the ASCII and invalid cases accordingly. This mask-and-or
-		// approach prevents an additional branch.
-		mask := rune(x) << 31 >> 31 // Create 0x0000 or 0xFFFF.
-		return rune(p[0])&^mask | RuneError&mask, 1
-	}
-	sz := int(x & 7)
-	accept := acceptRanges[x>>4]
-	if n < sz {
-		return RuneError, 1
-	}
-	b1 := p[1]
-	if b1 < accept.lo || accept.hi < b1 {
-		return RuneError, 1
-	}
-	if sz <= 2 { // <= instead of == to help the compiler eliminate some bounds checks
-		return rune(p0&mask2)<<6 | rune(b1&maskx), 2
-	}
-	b2 := p[2]
-	if b2 < locb || hicb < b2 {
-		return RuneError, 1
-	}
-	if sz <= 3 {
-		return rune(p0&mask3)<<12 | rune(b1&maskx)<<6 | rune(b2&maskx), 3
-	}
-	b3 := p[3]
-	if b3 < locb || hicb < b3 {
-		return RuneError, 1
-	}
-	return rune(p0&mask4)<<18 | rune(b1&maskx)<<12 | rune(b2&maskx)<<6 | rune(b3&maskx), 4
-}
-
-// DecodeRuneInString is like DecodeRune but its input is a string. If s is
-// empty it returns (RuneError, 0). Otherwise, if the encoding is invalid, it
-// returns (RuneError, 1). Both are impossible results for correct, non-empty
-// UTF-8.
-//
-// An encoding is invalid if it is incorrect UTF-8, encodes a rune that is
-// out of range, or is not the shortest possible UTF-8 encoding for the
-// value. No other validation is performed.
-func DecodeRuneInString(s string) (r rune, size int) {
-	n := len(s)
-	if n < 1 {
-		return RuneError, 0
-	}
-	s0 := s[0]
-	x := first[s0]
-	if x >= as {
-		// The following code simulates an additional check for x == xx and
-		// handling the ASCII and invalid cases accordingly. This mask-and-or
-		// approach prevents an additional branch.
-		mask := rune(x) << 31 >> 31 // Create 0x0000 or 0xFFFF.
-		return rune(s[0])&^mask | RuneError&mask, 1
-	}
-	sz := int(x & 7)
-	accept := acceptRanges[x>>4]
-	if n < sz {
-		return RuneError, 1
-	}
-	s1 := s[1]
-	if s1 < accept.lo || accept.hi < s1 {
-		return RuneError, 1
-	}
-	if sz <= 2 { // <= instead of == to help the compiler eliminate some bounds checks
-		return rune(s0&mask2)<<6 | rune(s1&maskx), 2
-	}
-	s2 := s[2]
-	if s2 < locb || hicb < s2 {
-		return RuneError, 1
-	}
-	if sz <= 3 {
-		return rune(s0&mask3)<<12 | rune(s1&maskx)<<6 | rune(s2&maskx), 3
-	}
-	s3 := s[3]
-	if s3 < locb || hicb < s3 {
-		return RuneError, 1
-	}
-	return rune(s0&mask4)<<18 | rune(s1&maskx)<<12 | rune(s2&maskx)<<6 | rune(s3&maskx), 4
-}
-
-// DecodeLastRune unpacks the last UTF-8 encoding in p and returns the rune and
-// its width in bytes. If p is empty it returns (RuneError, 0). Otherwise, if
-// the encoding is invalid, it returns (RuneError, 1). Both are impossible
-// results for correct, non-empty UTF-8.
-//
-// An encoding is invalid if it is incorrect UTF-8, encodes a rune that is
-// out of range, or is not the shortest possible UTF-8 encoding for the
-// value. No other validation is performed.
-func DecodeLastRune(p []byte) (r rune, size int) {
-	end := len(p)
-	if end == 0 {
-		return RuneError, 0
-	}
-	start := end - 1
-	r = rune(p[start])
-	if r < RuneSelf {
-		return r, 1
-	}
-	// guard against O(n^2) behavior when traversing
-	// backwards through strings with long sequences of
-	// invalid UTF-8.
-	lim := end - UTFMax
-	if lim < 0 {
-		lim = 0
-	}
-	for start--; start >= lim; start-- {
-		if RuneStart(p[start]) {
-			break
-		}
-	}
-	if start < 0 {
-		start = 0
-	}
-	r, size = DecodeRune(p[start:end])
-	if start+size != end {
-		return RuneError, 1
-	}
-	return r, size
-}
-
-// DecodeLastRuneInString is like DecodeLastRune but its input is a string. If
-// s is empty it returns (RuneError, 0). Otherwise, if the encoding is invalid,
-// it returns (RuneError, 1). Both are impossible results for correct,
-// non-empty UTF-8.
-//
-// An encoding is invalid if it is incorrect UTF-8, encodes a rune that is
-// out of range, or is not the shortest possible UTF-8 encoding for the
-// value. No other validation is performed.
-func DecodeLastRuneInString(s string) (r rune, size int) {
-	end := len(s)
-	if end == 0 {
-		return RuneError, 0
-	}
-	start := end - 1
-	r = rune(s[start])
-	if r < RuneSelf {
-		return r, 1
-	}
-	// guard against O(n^2) behavior when traversing
-	// backwards through strings with long sequences of
-	// invalid UTF-8.
-	lim := end - UTFMax
-	if lim < 0 {
-		lim = 0
-	}
-	for start--; start >= lim; start-- {
-		if RuneStart(s[start]) {
-			break
-		}
-	}
-	if start < 0 {
-		start = 0
-	}
-	r, size = DecodeRuneInString(s[start:end])
-	if start+size != end {
-		return RuneError, 1
-	}
-	return r, size
-}
-
-// RuneLen returns the number of bytes required to encode the rune.
-// It returns -1 if the rune is not a valid value to encode in UTF-8.
-func RuneLen(r rune) int {
-	switch {
-	case r < 0:
-		return -1
-	case r <= rune1Max:
-		return 1
-	case r <= rune2Max:
-		return 2
-	case surrogateMin <= r && r <= surrogateMax:
-		return -1
-	case r <= rune3Max:
-		return 3
-	case r <= MaxRune:
-		return 4
-	}
-	return -1
-}
-
-// EncodeRune writes into p (which must be large enough) the UTF-8 encoding of the rune.
-// If the rune is out of range, it writes the encoding of RuneError.
-// It returns the number of bytes written.
-func EncodeRune(p []byte, r rune) int {
-	// Negative values are erroneous. Making it unsigned addresses the problem.
-	switch i := uint32(r); {
-	case i <= rune1Max:
-		p[0] = byte(r)
-		return 1
-	case i <= rune2Max:
-		_ = p[1] // eliminate bounds checks
-		p[0] = t2 | byte(r>>6)
-		p[1] = tx | byte(r)&maskx
-		return 2
-	case i > MaxRune, surrogateMin <= i && i <= surrogateMax:
-		r = RuneError
-		fallthrough
-	case i <= rune3Max:
-		_ = p[2] // eliminate bounds checks
-		p[0] = t3 | byte(r>>12)
-		p[1] = tx | byte(r>>6)&maskx
-		p[2] = tx | byte(r)&maskx
-		return 3
-	default:
-		_ = p[3] // eliminate bounds checks
-		p[0] = t4 | byte(r>>18)
-		p[1] = tx | byte(r>>12)&maskx
-		p[2] = tx | byte(r>>6)&maskx
-		p[3] = tx | byte(r)&maskx
-		return 4
-	}
-}
-
-// AppendRune appends the UTF-8 encoding of r to the end of p and
-// returns the extended buffer. If the rune is out of range,
-// it appends the encoding of RuneError.
-func AppendRune(p []byte, r rune) []byte {
-	// This function is inlineable for fast handling of ASCII.
-	if uint32(r) <= rune1Max {
-		return append(p, byte(r))
-	}
-	return appendRuneNonASCII(p, r)
-}
-
-func appendRuneNonASCII(p []byte, r rune) []byte {
-	// Negative values are erroneous. Making it unsigned addresses the problem.
-	switch i := uint32(r); {
-	case i <= rune2Max:
-		return append(p, t2|byte(r>>6), tx|byte(r)&maskx)
-	case i > MaxRune, surrogateMin <= i && i <= surrogateMax:
-		r = RuneError
-		fallthrough
-	case i <= rune3Max:
-		return append(p, t3|byte(r>>12), tx|byte(r>>6)&maskx, tx|byte(r)&maskx)
-	default:
-		return append(p, t4|byte(r>>18), tx|byte(r>>12)&maskx, tx|byte(r>>6)&maskx, tx|byte(r)&maskx)
-	}
-}
-
-// RuneCount returns the number of runes in p. Erroneous and short
-// encodings are treated as single runes of width 1 byte.
-func RuneCount(p []byte) int {
-	np := len(p)
-	var n int
-	for i := 0; i < np; {
-		n++
-		c := p[i]
-		if c < RuneSelf {
-			// ASCII fast path
-			i++
-			continue
-		}
-		x := first[c]
-		if x == xx {
-			i++ // invalid.
-			continue
-		}
-		size := int(x & 7)
-		if i+size > np {
-			i++ // Short or invalid.
-			continue
-		}
-		accept := acceptRanges[x>>4]
-		if c := p[i+1]; c < accept.lo || accept.hi < c {
-			size = 1
-		} else if size == 2 {
-		} else if c := p[i+2]; c < locb || hicb < c {
-			size = 1
-		} else if size == 3 {
-		} else if c := p[i+3]; c < locb || hicb < c {
-			size = 1
-		}
-		i += size
-	}
-	return n
-}
-
-// RuneCountInString is like RuneCount but its input is a string.
-func RuneCountInString(s string) (n int) {
-	ns := len(s)
-	for i := 0; i < ns; n++ {
-		c := s[i]
-		if c < RuneSelf {
-			// ASCII fast path
-			i++
-			continue
-		}
-		x := first[c]
-		if x == xx {
-			i++ // invalid.
-			continue
-		}
-		size := int(x & 7)
-		if i+size > ns {
-			i++ // Short or invalid.
-			continue
-		}
-		accept := acceptRanges[x>>4]
-		if c := s[i+1]; c < accept.lo || accept.hi < c {
-			size = 1
-		} else if size == 2 {
-		} else if c := s[i+2]; c < locb || hicb < c {
-			size = 1
-		} else if size == 3 {
-		} else if c := s[i+3]; c < locb || hicb < c {
-			size = 1
-		}
-		i += size
-	}
-	return n
-}
-
-// RuneStart reports whether the byte could be the first byte of an encoded,
-// possibly invalid rune. Second and subsequent bytes always have the top two
-// bits set to 10.
-func RuneStart(b byte) bool { return b&0xC0 != 0x80 }
-
-// Valid reports whether p consists entirely of valid UTF-8-encoded runes.
-func Valid(p []byte) bool {
-	// Fast path. Check for and skip 8 bytes of ASCII characters per iteration.
-	for len(p) >= 8 {
-		// Combining two 32 bit loads allows the same code to be used
-		// for 32 and 64 bit platforms.
-		// The compiler can generate a 32bit load for first32 and second32
-		// on many platforms. See test/codegen/memcombine.go.
-		first32 := uint32(p[0]) | uint32(p[1])<<8 | uint32(p[2])<<16 | uint32(p[3])<<24
-		second32 := uint32(p[4]) | uint32(p[5])<<8 | uint32(p[6])<<16 | uint32(p[7])<<24
-		if (first32|second32)&0x80808080 != 0 {
-			// Found a non ASCII byte (>= RuneSelf).
-			break
-		}
-		p = p[8:]
-	}
-	n := len(p)
-	for i := 0; i < n; {
-		pi := p[i]
-		if pi < RuneSelf {
-			i++
-			continue
-		}
-		x := first[pi]
-		if x == xx {
-			return false // Illegal starter byte.
-		}
-		size := int(x & 7)
-		if i+size > n {
-			return false // Short or invalid.
-		}
-		accept := acceptRanges[x>>4]
-		if c := p[i+1]; c < accept.lo || accept.hi < c {
-			return false
-		} else if size == 2 {
-		} else if c := p[i+2]; c < locb || hicb < c {
-			return false
-		} else if size == 3 {
-		} else if c := p[i+3]; c < locb || hicb < c {
-			return false
-		}
-		i += size
-	}
-	return true
-}
-
-// ValidString reports whether s consists entirely of valid UTF-8-encoded runes.
-func ValidString(s string) bool {
-	// Fast path. Check for and skip 8 bytes of ASCII characters per iteration.
-	for len(s) >= 8 {
-		// Combining two 32 bit loads allows the same code to be used
-		// for 32 and 64 bit platforms.
-		// The compiler can generate a 32bit load for first32 and second32
-		// on many platforms. See test/codegen/memcombine.go.
-		first32 := uint32(s[0]) | uint32(s[1])<<8 | uint32(s[2])<<16 | uint32(s[3])<<24
-		second32 := uint32(s[4]) | uint32(s[5])<<8 | uint32(s[6])<<16 | uint32(s[7])<<24
-		if (first32|second32)&0x80808080 != 0 {
-			// Found a non ASCII byte (>= RuneSelf).
-			break
-		}
-		s = s[8:]
-	}
-	n := len(s)
-	for i := 0; i < n; {
-		si := s[i]
-		if si < RuneSelf {
-			i++
-			continue
-		}
-		x := first[si]
-		if x == xx {
-			return false // Illegal starter byte.
-		}
-		size := int(x & 7)
-		if i+size > n {
-			return false // Short or invalid.
-		}
-		accept := acceptRanges[x>>4]
-		if c := s[i+1]; c < accept.lo || accept.hi < c {
-			return false
-		} else if size == 2 {
-		} else if c := s[i+2]; c < locb || hicb < c {
-			return false
-		} else if size == 3 {
-		} else if c := s[i+3]; c < locb || hicb < c {
-			return false
-		}
-		i += size
-	}
-	return true
-}
-
-// ValidRune reports whether r can be legally encoded as UTF-8.
-// Code points that are out of range or a surrogate half are illegal.
-func ValidRune(r rune) bool {
-	switch {
-	case 0 <= r && r < surrogateMin:
-		return true
-	case surrogateMax < r && r <= MaxRune:
-		return true
-	}
-	return false
-}
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/cryptobyte/builder.go b/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/cryptobyte/builder.go
deleted file mode 100644
index ca7b1db5ce..0000000000
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/cryptobyte/builder.go
+++ /dev/null
@@ -1,337 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cryptobyte
-
-import (
-	"errors"
-	"fmt"
-)
-
-// A Builder builds byte strings from fixed-length and length-prefixed values.
-// Builders either allocate space as needed, or are ‘fixed’, which means that
-// they write into a given buffer and produce an error if it's exhausted.
-//
-// The zero value is a usable Builder that allocates space as needed.
-//
-// Simple values are marshaled and appended to a Builder using methods on the
-// Builder. Length-prefixed values are marshaled by providing a
-// BuilderContinuation, which is a function that writes the inner contents of
-// the value to a given Builder. See the documentation for BuilderContinuation
-// for details.
-type Builder struct {
-	err            error
-	result         []byte
-	fixedSize      bool
-	child          *Builder
-	offset         int
-	pendingLenLen  int
-	pendingIsASN1  bool
-	inContinuation *bool
-}
-
-// NewBuilder creates a Builder that appends its output to the given buffer.
-// Like append(), the slice will be reallocated if its capacity is exceeded.
-// Use Bytes to get the final buffer.
-func NewBuilder(buffer []byte) *Builder {
-	return &Builder{
-		result: buffer,
-	}
-}
-
-// NewFixedBuilder creates a Builder that appends its output into the given
-// buffer. This builder does not reallocate the output buffer. Writes that
-// would exceed the buffer's capacity are treated as an error.
-func NewFixedBuilder(buffer []byte) *Builder {
-	return &Builder{
-		result:    buffer,
-		fixedSize: true,
-	}
-}
-
-// SetError sets the value to be returned as the error from Bytes. Writes
-// performed after calling SetError are ignored.
-func (b *Builder) SetError(err error) {
-	b.err = err
-}
-
-// Bytes returns the bytes written by the builder or an error if one has
-// occurred during building.
-func (b *Builder) Bytes() ([]byte, error) {
-	if b.err != nil {
-		return nil, b.err
-	}
-	return b.result[b.offset:], nil
-}
-
-// BytesOrPanic returns the bytes written by the builder or panics if an error
-// has occurred during building.
-func (b *Builder) BytesOrPanic() []byte {
-	if b.err != nil {
-		panic(b.err)
-	}
-	return b.result[b.offset:]
-}
-
-// AddUint8 appends an 8-bit value to the byte string.
-func (b *Builder) AddUint8(v uint8) {
-	b.add(byte(v))
-}
-
-// AddUint16 appends a big-endian, 16-bit value to the byte string.
-func (b *Builder) AddUint16(v uint16) {
-	b.add(byte(v>>8), byte(v))
-}
-
-// AddUint24 appends a big-endian, 24-bit value to the byte string. The highest
-// byte of the 32-bit input value is silently truncated.
-func (b *Builder) AddUint24(v uint32) {
-	b.add(byte(v>>16), byte(v>>8), byte(v))
-}
-
-// AddUint32 appends a big-endian, 32-bit value to the byte string.
-func (b *Builder) AddUint32(v uint32) {
-	b.add(byte(v>>24), byte(v>>16), byte(v>>8), byte(v))
-}
-
-// AddBytes appends a sequence of bytes to the byte string.
-func (b *Builder) AddBytes(v []byte) {
-	b.add(v...)
-}
-
-// BuilderContinuation is a continuation-passing interface for building
-// length-prefixed byte sequences. Builder methods for length-prefixed
-// sequences (AddUint8LengthPrefixed etc) will invoke the BuilderContinuation
-// supplied to them. The child builder passed to the continuation can be used
-// to build the content of the length-prefixed sequence. For example:
-//
-//   parent := cryptobyte.NewBuilder()
-//   parent.AddUint8LengthPrefixed(func (child *Builder) {
-//     child.AddUint8(42)
-//     child.AddUint8LengthPrefixed(func (grandchild *Builder) {
-//       grandchild.AddUint8(5)
-//     })
-//   })
-//
-// It is an error to write more bytes to the child than allowed by the reserved
-// length prefix. After the continuation returns, the child must be considered
-// invalid, i.e. users must not store any copies or references of the child
-// that outlive the continuation.
-//
-// If the continuation panics with a value of type BuildError then the inner
-// error will be returned as the error from Bytes. If the child panics
-// otherwise then Bytes will repanic with the same value.
-type BuilderContinuation func(child *Builder)
-
-// BuildError wraps an error. If a BuilderContinuation panics with this value,
-// the panic will be recovered and the inner error will be returned from
-// Builder.Bytes.
-type BuildError struct {
-	Err error
-}
-
-// AddUint8LengthPrefixed adds a 8-bit length-prefixed byte sequence.
-func (b *Builder) AddUint8LengthPrefixed(f BuilderContinuation) {
-	b.addLengthPrefixed(1, false, f)
-}
-
-// AddUint16LengthPrefixed adds a big-endian, 16-bit length-prefixed byte sequence.
-func (b *Builder) AddUint16LengthPrefixed(f BuilderContinuation) {
-	b.addLengthPrefixed(2, false, f)
-}
-
-// AddUint24LengthPrefixed adds a big-endian, 24-bit length-prefixed byte sequence.
-func (b *Builder) AddUint24LengthPrefixed(f BuilderContinuation) {
-	b.addLengthPrefixed(3, false, f)
-}
-
-// AddUint32LengthPrefixed adds a big-endian, 32-bit length-prefixed byte sequence.
-func (b *Builder) AddUint32LengthPrefixed(f BuilderContinuation) {
-	b.addLengthPrefixed(4, false, f)
-}
-
-func (b *Builder) callContinuation(f BuilderContinuation, arg *Builder) {
-	if !*b.inContinuation {
-		*b.inContinuation = true
-
-		defer func() {
-			*b.inContinuation = false
-
-			r := recover()
-			if r == nil {
-				return
-			}
-
-			if buildError, ok := r.(BuildError); ok {
-				b.err = buildError.Err
-			} else {
-				panic(r)
-			}
-		}()
-	}
-
-	f(arg)
-}
-
-func (b *Builder) addLengthPrefixed(lenLen int, isASN1 bool, f BuilderContinuation) {
-	// Subsequent writes can be ignored if the builder has encountered an error.
-	if b.err != nil {
-		return
-	}
-
-	offset := len(b.result)
-	b.add(make([]byte, lenLen)...)
-
-	if b.inContinuation == nil {
-		b.inContinuation = new(bool)
-	}
-
-	b.child = &Builder{
-		result:         b.result,
-		fixedSize:      b.fixedSize,
-		offset:         offset,
-		pendingLenLen:  lenLen,
-		pendingIsASN1:  isASN1,
-		inContinuation: b.inContinuation,
-	}
-
-	b.callContinuation(f, b.child)
-	b.flushChild()
-	if b.child != nil {
-		panic("cryptobyte: internal error")
-	}
-}
-
-func (b *Builder) flushChild() {
-	if b.child == nil {
-		return
-	}
-	b.child.flushChild()
-	child := b.child
-	b.child = nil
-
-	if child.err != nil {
-		b.err = child.err
-		return
-	}
-
-	length := len(child.result) - child.pendingLenLen - child.offset
-
-	if length < 0 {
-		panic("cryptobyte: internal error") // result unexpectedly shrunk
-	}
-
-	if child.pendingIsASN1 {
-		// For ASN.1, we reserved a single byte for the length. If that turned out
-		// to be incorrect, we have to move the contents along in order to make
-		// space.
-		if child.pendingLenLen != 1 {
-			panic("cryptobyte: internal error")
-		}
-		var lenLen, lenByte uint8
-		if int64(length) > 0xfffffffe {
-			b.err = errors.New("pending ASN.1 child too long")
-			return
-		} else if length > 0xffffff {
-			lenLen = 5
-			lenByte = 0x80 | 4
-		} else if length > 0xffff {
-			lenLen = 4
-			lenByte = 0x80 | 3
-		} else if length > 0xff {
-			lenLen = 3
-			lenByte = 0x80 | 2
-		} else if length > 0x7f {
-			lenLen = 2
-			lenByte = 0x80 | 1
-		} else {
-			lenLen = 1
-			lenByte = uint8(length)
-			length = 0
-		}
-
-		// Insert the initial length byte, make space for successive length bytes,
-		// and adjust the offset.
-		child.result[child.offset] = lenByte
-		extraBytes := int(lenLen - 1)
-		if extraBytes != 0 {
-			child.add(make([]byte, extraBytes)...)
-			childStart := child.offset + child.pendingLenLen
-			copy(child.result[childStart+extraBytes:], child.result[childStart:])
-		}
-		child.offset++
-		child.pendingLenLen = extraBytes
-	}
-
-	l := length
-	for i := child.pendingLenLen - 1; i >= 0; i-- {
-		child.result[child.offset+i] = uint8(l)
-		l >>= 8
-	}
-	if l != 0 {
-		b.err = fmt.Errorf("cryptobyte: pending child length %d exceeds %d-byte length prefix", length, child.pendingLenLen)
-		return
-	}
-
-	if b.fixedSize && &b.result[0] != &child.result[0] {
-		panic("cryptobyte: BuilderContinuation reallocated a fixed-size buffer")
-	}
-
-	b.result = child.result
-}
-
-func (b *Builder) add(bytes ...byte) {
-	if b.err != nil {
-		return
-	}
-	if b.child != nil {
-		panic("cryptobyte: attempted write while child is pending")
-	}
-	if len(b.result)+len(bytes) < len(bytes) {
-		b.err = errors.New("cryptobyte: length overflow")
-	}
-	if b.fixedSize && len(b.result)+len(bytes) > cap(b.result) {
-		b.err = errors.New("cryptobyte: Builder is exceeding its fixed-size buffer")
-		return
-	}
-	b.result = append(b.result, bytes...)
-}
-
-// Unwrite rolls back n bytes written directly to the Builder. An attempt by a
-// child builder passed to a continuation to unwrite bytes from its parent will
-// panic.
-func (b *Builder) Unwrite(n int) {
-	if b.err != nil {
-		return
-	}
-	if b.child != nil {
-		panic("cryptobyte: attempted unwrite while child is pending")
-	}
-	length := len(b.result) - b.pendingLenLen - b.offset
-	if length < 0 {
-		panic("cryptobyte: internal error")
-	}
-	if n > length {
-		panic("cryptobyte: attempted to unwrite more than was written")
-	}
-	b.result = b.result[:len(b.result)-n]
-}
-
-// A MarshalingValue marshals itself into a Builder.
-type MarshalingValue interface {
-	// Marshal is called by Builder.AddValue. It receives a pointer to a builder
-	// to marshal itself into. It may return an error that occurred during
-	// marshaling, such as unset or invalid values.
-	Marshal(b *Builder) error
-}
-
-// AddValue calls Marshal on v, passing a pointer to the builder to append to.
-// If Marshal returns an error, it is set on the Builder so that subsequent
-// appends don't have an effect.
-func (b *Builder) AddValue(v MarshalingValue) {
-	err := v.Marshal(b)
-	if err != nil {
-		b.err = err
-	}
-}
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/curve25519/internal/field/fe_amd64.go b/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/curve25519/internal/field/fe_amd64.go
deleted file mode 100644
index 44dc8e8caf..0000000000
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/curve25519/internal/field/fe_amd64.go
+++ /dev/null
@@ -1,13 +0,0 @@
-// Code generated by command: go run fe_amd64_asm.go -out ../fe_amd64.s -stubs ../fe_amd64.go -pkg field. DO NOT EDIT.
-
-// +build amd64,gc,!purego
-
-package field
-
-// feMul sets out = a * b. It works like feMulGeneric.
-//go:noescape
-func feMul(out *Element, a *Element, b *Element)
-
-// feSquare sets out = a * a. It works like feSquareGeneric.
-//go:noescape
-func feSquare(out *Element, a *Element)
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/internal/poly1305/sum_generic.go b/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/internal/poly1305/sum_generic.go
deleted file mode 100644
index c942a65904..0000000000
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/internal/poly1305/sum_generic.go
+++ /dev/null
@@ -1,310 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file provides the generic implementation of Sum and MAC. Other files
-// might provide optimized assembly implementations of some of this code.
-
-package poly1305
-
-import "encoding/binary"
-
-// Poly1305 [RFC 7539] is a relatively simple algorithm: the authentication tag
-// for a 64 bytes message is approximately
-//
-//     s + m[0:16] * r⁴ + m[16:32] * r³ + m[32:48] * r² + m[48:64] * r  mod  2¹³⁰ - 5
-//
-// for some secret r and s. It can be computed sequentially like
-//
-//     for len(msg) > 0:
-//         h += read(msg, 16)
-//         h *= r
-//         h %= 2¹³⁰ - 5
-//     return h + s
-//
-// All the complexity is about doing performant constant-time math on numbers
-// larger than any available numeric type.
-
-func sumGeneric(out *[TagSize]byte, msg []byte, key *[32]byte) {
-	h := newMACGeneric(key)
-	h.Write(msg)
-	h.Sum(out)
-}
-
-func newMACGeneric(key *[32]byte) macGeneric {
-	m := macGeneric{}
-	initialize(key, &m.macState)
-	return m
-}
-
-// macState holds numbers in saturated 64-bit little-endian limbs. That is,
-// the value of [x0, x1, x2] is x[0] + x[1] * 2⁶⁴ + x[2] * 2¹²⁸.
-type macState struct {
-	// h is the main accumulator. It is to be interpreted modulo 2¹³⁰ - 5, but
-	// can grow larger during and after rounds. It must, however, remain below
-	// 2 * (2¹³⁰ - 5).
-	h [3]uint64
-	// r and s are the private key components.
-	r [2]uint64
-	s [2]uint64
-}
-
-type macGeneric struct {
-	macState
-
-	buffer [TagSize]byte
-	offset int
-}
-
-// Write splits the incoming message into TagSize chunks, and passes them to
-// update. It buffers incomplete chunks.
-func (h *macGeneric) Write(p []byte) (int, error) {
-	nn := len(p)
-	if h.offset > 0 {
-		n := copy(h.buffer[h.offset:], p)
-		if h.offset+n < TagSize {
-			h.offset += n
-			return nn, nil
-		}
-		p = p[n:]
-		h.offset = 0
-		updateGeneric(&h.macState, h.buffer[:])
-	}
-	if n := len(p) - (len(p) % TagSize); n > 0 {
-		updateGeneric(&h.macState, p[:n])
-		p = p[n:]
-	}
-	if len(p) > 0 {
-		h.offset += copy(h.buffer[h.offset:], p)
-	}
-	return nn, nil
-}
-
-// Sum flushes the last incomplete chunk from the buffer, if any, and generates
-// the MAC output. It does not modify its state, in order to allow for multiple
-// calls to Sum, even if no Write is allowed after Sum.
-func (h *macGeneric) Sum(out *[TagSize]byte) {
-	state := h.macState
-	if h.offset > 0 {
-		updateGeneric(&state, h.buffer[:h.offset])
-	}
-	finalize(out, &state.h, &state.s)
-}
-
-// [rMask0, rMask1] is the specified Poly1305 clamping mask in little-endian. It
-// clears some bits of the secret coefficient to make it possible to implement
-// multiplication more efficiently.
-const (
-	rMask0 = 0x0FFFFFFC0FFFFFFF
-	rMask1 = 0x0FFFFFFC0FFFFFFC
-)
-
-// initialize loads the 256-bit key into the two 128-bit secret values r and s.
-func initialize(key *[32]byte, m *macState) {
-	m.r[0] = binary.LittleEndian.Uint64(key[0:8]) & rMask0
-	m.r[1] = binary.LittleEndian.Uint64(key[8:16]) & rMask1
-	m.s[0] = binary.LittleEndian.Uint64(key[16:24])
-	m.s[1] = binary.LittleEndian.Uint64(key[24:32])
-}
-
-// uint128 holds a 128-bit number as two 64-bit limbs, for use with the
-// bits.Mul64 and bits.Add64 intrinsics.
-type uint128 struct {
-	lo, hi uint64
-}
-
-func mul64(a, b uint64) uint128 {
-	hi, lo := bitsMul64(a, b)
-	return uint128{lo, hi}
-}
-
-func add128(a, b uint128) uint128 {
-	lo, c := bitsAdd64(a.lo, b.lo, 0)
-	hi, c := bitsAdd64(a.hi, b.hi, c)
-	if c != 0 {
-		panic("poly1305: unexpected overflow")
-	}
-	return uint128{lo, hi}
-}
-
-func shiftRightBy2(a uint128) uint128 {
-	a.lo = a.lo>>2 | (a.hi&3)<<62
-	a.hi = a.hi >> 2
-	return a
-}
-
-// updateGeneric absorbs msg into the state.h accumulator. For each chunk m of
-// 128 bits of message, it computes
-//
-//     h₊ = (h + m) * r  mod  2¹³⁰ - 5
-//
-// If the msg length is not a multiple of TagSize, it assumes the last
-// incomplete chunk is the final one.
-func updateGeneric(state *macState, msg []byte) {
-	h0, h1, h2 := state.h[0], state.h[1], state.h[2]
-	r0, r1 := state.r[0], state.r[1]
-
-	for len(msg) > 0 {
-		var c uint64
-
-		// For the first step, h + m, we use a chain of bits.Add64 intrinsics.
-		// The resulting value of h might exceed 2¹³⁰ - 5, but will be partially
-		// reduced at the end of the multiplication below.
-		//
-		// The spec requires us to set a bit just above the message size, not to
-		// hide leading zeroes. For full chunks, that's 1 << 128, so we can just
-		// add 1 to the most significant (2¹²⁸) limb, h2.
-		if len(msg) >= TagSize {
-			h0, c = bitsAdd64(h0, binary.LittleEndian.Uint64(msg[0:8]), 0)
-			h1, c = bitsAdd64(h1, binary.LittleEndian.Uint64(msg[8:16]), c)
-			h2 += c + 1
-
-			msg = msg[TagSize:]
-		} else {
-			var buf [TagSize]byte
-			copy(buf[:], msg)
-			buf[len(msg)] = 1
-
-			h0, c = bitsAdd64(h0, binary.LittleEndian.Uint64(buf[0:8]), 0)
-			h1, c = bitsAdd64(h1, binary.LittleEndian.Uint64(buf[8:16]), c)
-			h2 += c
-
-			msg = nil
-		}
-
-		// Multiplication of big number limbs is similar to elementary school
-		// columnar multiplication. Instead of digits, there are 64-bit limbs.
-		//
-		// We are multiplying a 3 limbs number, h, by a 2 limbs number, r.
-		//
-		//                        h2    h1    h0  x
-		//                              r1    r0  =
-		//                       ----------------
-		//                      h2r0  h1r0  h0r0     <-- individual 128-bit products
-		//            +   h2r1  h1r1  h0r1
-		//               ------------------------
-		//                 m3    m2    m1    m0      <-- result in 128-bit overlapping limbs
-		//               ------------------------
-		//         m3.hi m2.hi m1.hi m0.hi           <-- carry propagation
-		//     +         m3.lo m2.lo m1.lo m0.lo
-		//        -------------------------------
-		//           t4    t3    t2    t1    t0      <-- final result in 64-bit limbs
-		//
-		// The main difference from pen-and-paper multiplication is that we do
-		// carry propagation in a separate step, as if we wrote two digit sums
-		// at first (the 128-bit limbs), and then carried the tens all at once.
-
-		h0r0 := mul64(h0, r0)
-		h1r0 := mul64(h1, r0)
-		h2r0 := mul64(h2, r0)
-		h0r1 := mul64(h0, r1)
-		h1r1 := mul64(h1, r1)
-		h2r1 := mul64(h2, r1)
-
-		// Since h2 is known to be at most 7 (5 + 1 + 1), and r0 and r1 have their
-		// top 4 bits cleared by rMask{0,1}, we know that their product is not going
-		// to overflow 64 bits, so we can ignore the high part of the products.
-		//
-		// This also means that the product doesn't have a fifth limb (t4).
-		if h2r0.hi != 0 {
-			panic("poly1305: unexpected overflow")
-		}
-		if h2r1.hi != 0 {
-			panic("poly1305: unexpected overflow")
-		}
-
-		m0 := h0r0
-		m1 := add128(h1r0, h0r1) // These two additions don't overflow thanks again
-		m2 := add128(h2r0, h1r1) // to the 4 masked bits at the top of r0 and r1.
-		m3 := h2r1
-
-		t0 := m0.lo
-		t1, c := bitsAdd64(m1.lo, m0.hi, 0)
-		t2, c := bitsAdd64(m2.lo, m1.hi, c)
-		t3, _ := bitsAdd64(m3.lo, m2.hi, c)
-
-		// Now we have the result as 4 64-bit limbs, and we need to reduce it
-		// modulo 2¹³⁰ - 5. The special shape of this Crandall prime lets us do
-		// a cheap partial reduction according to the reduction identity
-		//
-		//     c * 2¹³⁰ + n  =  c * 5 + n  mod  2¹³⁰ - 5
-		//
-		// because 2¹³⁰ = 5 mod 2¹³⁰ - 5. Partial reduction since the result is
-		// likely to be larger than 2¹³⁰ - 5, but still small enough to fit the
-		// assumptions we make about h in the rest of the code.
-		//
-		// See also https://speakerdeck.com/gtank/engineering-prime-numbers?slide=23
-
-		// We split the final result at the 2¹³⁰ mark into h and cc, the carry.
-		// Note that the carry bits are effectively shifted left by 2, in other
-		// words, cc = c * 4 for the c in the reduction identity.
-		h0, h1, h2 = t0, t1, t2&maskLow2Bits
-		cc := uint128{t2 & maskNotLow2Bits, t3}
-
-		// To add c * 5 to h, we first add cc = c * 4, and then add (cc >> 2) = c.
-
-		h0, c = bitsAdd64(h0, cc.lo, 0)
-		h1, c = bitsAdd64(h1, cc.hi, c)
-		h2 += c
-
-		cc = shiftRightBy2(cc)
-
-		h0, c = bitsAdd64(h0, cc.lo, 0)
-		h1, c = bitsAdd64(h1, cc.hi, c)
-		h2 += c
-
-		// h2 is at most 3 + 1 + 1 = 5, making the whole of h at most
-		//
-		//     5 * 2¹²⁸ + (2¹²⁸ - 1) = 6 * 2¹²⁸ - 1
-	}
-
-	state.h[0], state.h[1], state.h[2] = h0, h1, h2
-}
-
-const (
-	maskLow2Bits    uint64 = 0x0000000000000003
-	maskNotLow2Bits uint64 = ^maskLow2Bits
-)
-
-// select64 returns x if v == 1 and y if v == 0, in constant time.
-func select64(v, x, y uint64) uint64 { return ^(v-1)&x | (v-1)&y }
-
-// [p0, p1, p2] is 2¹³⁰ - 5 in little endian order.
-const (
-	p0 = 0xFFFFFFFFFFFFFFFB
-	p1 = 0xFFFFFFFFFFFFFFFF
-	p2 = 0x0000000000000003
-)
-
-// finalize completes the modular reduction of h and computes
-//
-//     out = h + s  mod  2¹²⁸
-//
-func finalize(out *[TagSize]byte, h *[3]uint64, s *[2]uint64) {
-	h0, h1, h2 := h[0], h[1], h[2]
-
-	// After the partial reduction in updateGeneric, h might be more than
-	// 2¹³⁰ - 5, but will be less than 2 * (2¹³⁰ - 5). To complete the reduction
-	// in constant time, we compute t = h - (2¹³⁰ - 5), and select h as the
-	// result if the subtraction underflows, and t otherwise.
-
-	hMinusP0, b := bitsSub64(h0, p0, 0)
-	hMinusP1, b := bitsSub64(h1, p1, b)
-	_, b = bitsSub64(h2, p2, b)
-
-	// h = h if h < p else h - p
-	h0 = select64(b, h0, hMinusP0)
-	h1 = select64(b, h1, hMinusP1)
-
-	// Finally, we compute the last Poly1305 step
-	//
-	//     tag = h + s  mod  2¹²⁸
-	//
-	// by just doing a wide addition with the 128 low bits of h and discarding
-	// the overflow.
-	h0, c := bitsAdd64(h0, s[0], 0)
-	h1, _ = bitsAdd64(h1, s[1], c)
-
-	binary.LittleEndian.PutUint64(out[0:8], h0)
-	binary.LittleEndian.PutUint64(out[8:16], h1)
-}
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/dns/dnsmessage/message.go b/contrib/go/_std_1.18/src/vendor/golang.org/x/net/dns/dnsmessage/message.go
deleted file mode 100644
index 8c24430c5c..0000000000
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/dns/dnsmessage/message.go
+++ /dev/null
@@ -1,2664 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package dnsmessage provides a mostly RFC 1035 compliant implementation of
-// DNS message packing and unpacking.
-//
-// The package also supports messages with Extension Mechanisms for DNS
-// (EDNS(0)) as defined in RFC 6891.
-//
-// This implementation is designed to minimize heap allocations and avoid
-// unnecessary packing and unpacking as much as possible.
-package dnsmessage
-
-import (
-	"errors"
-)
-
-// Message formats
-
-// A Type is a type of DNS request and response.
-type Type uint16
-
-const (
-	// ResourceHeader.Type and Question.Type
-	TypeA     Type = 1
-	TypeNS    Type = 2
-	TypeCNAME Type = 5
-	TypeSOA   Type = 6
-	TypePTR   Type = 12
-	TypeMX    Type = 15
-	TypeTXT   Type = 16
-	TypeAAAA  Type = 28
-	TypeSRV   Type = 33
-	TypeOPT   Type = 41
-
-	// Question.Type
-	TypeWKS   Type = 11
-	TypeHINFO Type = 13
-	TypeMINFO Type = 14
-	TypeAXFR  Type = 252
-	TypeALL   Type = 255
-)
-
-var typeNames = map[Type]string{
-	TypeA:     "TypeA",
-	TypeNS:    "TypeNS",
-	TypeCNAME: "TypeCNAME",
-	TypeSOA:   "TypeSOA",
-	TypePTR:   "TypePTR",
-	TypeMX:    "TypeMX",
-	TypeTXT:   "TypeTXT",
-	TypeAAAA:  "TypeAAAA",
-	TypeSRV:   "TypeSRV",
-	TypeOPT:   "TypeOPT",
-	TypeWKS:   "TypeWKS",
-	TypeHINFO: "TypeHINFO",
-	TypeMINFO: "TypeMINFO",
-	TypeAXFR:  "TypeAXFR",
-	TypeALL:   "TypeALL",
-}
-
-// String implements fmt.Stringer.String.
-func (t Type) String() string {
-	if n, ok := typeNames[t]; ok {
-		return n
-	}
-	return printUint16(uint16(t))
-}
-
-// GoString implements fmt.GoStringer.GoString.
-func (t Type) GoString() string {
-	if n, ok := typeNames[t]; ok {
-		return "dnsmessage." + n
-	}
-	return printUint16(uint16(t))
-}
-
-// A Class is a type of network.
-type Class uint16
-
-const (
-	// ResourceHeader.Class and Question.Class
-	ClassINET   Class = 1
-	ClassCSNET  Class = 2
-	ClassCHAOS  Class = 3
-	ClassHESIOD Class = 4
-
-	// Question.Class
-	ClassANY Class = 255
-)
-
-var classNames = map[Class]string{
-	ClassINET:   "ClassINET",
-	ClassCSNET:  "ClassCSNET",
-	ClassCHAOS:  "ClassCHAOS",
-	ClassHESIOD: "ClassHESIOD",
-	ClassANY:    "ClassANY",
-}
-
-// String implements fmt.Stringer.String.
-func (c Class) String() string {
-	if n, ok := classNames[c]; ok {
-		return n
-	}
-	return printUint16(uint16(c))
-}
-
-// GoString implements fmt.GoStringer.GoString.
-func (c Class) GoString() string {
-	if n, ok := classNames[c]; ok {
-		return "dnsmessage." + n
-	}
-	return printUint16(uint16(c))
-}
-
-// An OpCode is a DNS operation code.
-type OpCode uint16
-
-// GoString implements fmt.GoStringer.GoString.
-func (o OpCode) GoString() string {
-	return printUint16(uint16(o))
-}
-
-// An RCode is a DNS response status code.
-type RCode uint16
-
-// Header.RCode values.
-const (
-	RCodeSuccess        RCode = 0 // NoError
-	RCodeFormatError    RCode = 1 // FormErr
-	RCodeServerFailure  RCode = 2 // ServFail
-	RCodeNameError      RCode = 3 // NXDomain
-	RCodeNotImplemented RCode = 4 // NotImp
-	RCodeRefused        RCode = 5 // Refused
-)
-
-var rCodeNames = map[RCode]string{
-	RCodeSuccess:        "RCodeSuccess",
-	RCodeFormatError:    "RCodeFormatError",
-	RCodeServerFailure:  "RCodeServerFailure",
-	RCodeNameError:      "RCodeNameError",
-	RCodeNotImplemented: "RCodeNotImplemented",
-	RCodeRefused:        "RCodeRefused",
-}
-
-// String implements fmt.Stringer.String.
-func (r RCode) String() string {
-	if n, ok := rCodeNames[r]; ok {
-		return n
-	}
-	return printUint16(uint16(r))
-}
-
-// GoString implements fmt.GoStringer.GoString.
-func (r RCode) GoString() string {
-	if n, ok := rCodeNames[r]; ok {
-		return "dnsmessage." + n
-	}
-	return printUint16(uint16(r))
-}
-
-func printPaddedUint8(i uint8) string {
-	b := byte(i)
-	return string([]byte{
-		b/100 + '0',
-		b/10%10 + '0',
-		b%10 + '0',
-	})
-}
-
-func printUint8Bytes(buf []byte, i uint8) []byte {
-	b := byte(i)
-	if i >= 100 {
-		buf = append(buf, b/100+'0')
-	}
-	if i >= 10 {
-		buf = append(buf, b/10%10+'0')
-	}
-	return append(buf, b%10+'0')
-}
-
-func printByteSlice(b []byte) string {
-	if len(b) == 0 {
-		return ""
-	}
-	buf := make([]byte, 0, 5*len(b))
-	buf = printUint8Bytes(buf, uint8(b[0]))
-	for _, n := range b[1:] {
-		buf = append(buf, ',', ' ')
-		buf = printUint8Bytes(buf, uint8(n))
-	}
-	return string(buf)
-}
-
-const hexDigits = "0123456789abcdef"
-
-func printString(str []byte) string {
-	buf := make([]byte, 0, len(str))
-	for i := 0; i < len(str); i++ {
-		c := str[i]
-		if c == '.' || c == '-' || c == ' ' ||
-			'A' <= c && c <= 'Z' ||
-			'a' <= c && c <= 'z' ||
-			'0' <= c && c <= '9' {
-			buf = append(buf, c)
-			continue
-		}
-
-		upper := c >> 4
-		lower := (c << 4) >> 4
-		buf = append(
-			buf,
-			'\\',
-			'x',
-			hexDigits[upper],
-			hexDigits[lower],
-		)
-	}
-	return string(buf)
-}
-
-func printUint16(i uint16) string {
-	return printUint32(uint32(i))
-}
-
-func printUint32(i uint32) string {
-	// Max value is 4294967295.
-	buf := make([]byte, 10)
-	for b, d := buf, uint32(1000000000); d > 0; d /= 10 {
-		b[0] = byte(i/d%10 + '0')
-		if b[0] == '0' && len(b) == len(buf) && len(buf) > 1 {
-			buf = buf[1:]
-		}
-		b = b[1:]
-		i %= d
-	}
-	return string(buf)
-}
-
-func printBool(b bool) string {
-	if b {
-		return "true"
-	}
-	return "false"
-}
-
-var (
-	// ErrNotStarted indicates that the prerequisite information isn't
-	// available yet because the previous records haven't been appropriately
-	// parsed, skipped or finished.
-	ErrNotStarted = errors.New("parsing/packing of this type isn't available yet")
-
-	// ErrSectionDone indicated that all records in the section have been
-	// parsed or finished.
-	ErrSectionDone = errors.New("parsing/packing of this section has completed")
-
-	errBaseLen            = errors.New("insufficient data for base length type")
-	errCalcLen            = errors.New("insufficient data for calculated length type")
-	errReserved           = errors.New("segment prefix is reserved")
-	errTooManyPtr         = errors.New("too many pointers (>10)")
-	errInvalidPtr         = errors.New("invalid pointer")
-	errNilResouceBody     = errors.New("nil resource body")
-	errResourceLen        = errors.New("insufficient data for resource body length")
-	errSegTooLong         = errors.New("segment length too long")
-	errZeroSegLen         = errors.New("zero length segment")
-	errResTooLong         = errors.New("resource length too long")
-	errTooManyQuestions   = errors.New("too many Questions to pack (>65535)")
-	errTooManyAnswers     = errors.New("too many Answers to pack (>65535)")
-	errTooManyAuthorities = errors.New("too many Authorities to pack (>65535)")
-	errTooManyAdditionals = errors.New("too many Additionals to pack (>65535)")
-	errNonCanonicalName   = errors.New("name is not in canonical format (it must end with a .)")
-	errStringTooLong      = errors.New("character string exceeds maximum length (255)")
-	errCompressedSRV      = errors.New("compressed name in SRV resource data")
-)
-
-// Internal constants.
-const (
-	// packStartingCap is the default initial buffer size allocated during
-	// packing.
-	//
-	// The starting capacity doesn't matter too much, but most DNS responses
-	// Will be <= 512 bytes as it is the limit for DNS over UDP.
-	packStartingCap = 512
-
-	// uint16Len is the length (in bytes) of a uint16.
-	uint16Len = 2
-
-	// uint32Len is the length (in bytes) of a uint32.
-	uint32Len = 4
-
-	// headerLen is the length (in bytes) of a DNS header.
-	//
-	// A header is comprised of 6 uint16s and no padding.
-	headerLen = 6 * uint16Len
-)
-
-type nestedError struct {
-	// s is the current level's error message.
-	s string
-
-	// err is the nested error.
-	err error
-}
-
-// nestedError implements error.Error.
-func (e *nestedError) Error() string {
-	return e.s + ": " + e.err.Error()
-}
-
-// Header is a representation of a DNS message header.
-type Header struct {
-	ID                 uint16
-	Response           bool
-	OpCode             OpCode
-	Authoritative      bool
-	Truncated          bool
-	RecursionDesired   bool
-	RecursionAvailable bool
-	RCode              RCode
-}
-
-func (m *Header) pack() (id uint16, bits uint16) {
-	id = m.ID
-	bits = uint16(m.OpCode)<<11 | uint16(m.RCode)
-	if m.RecursionAvailable {
-		bits |= headerBitRA
-	}
-	if m.RecursionDesired {
-		bits |= headerBitRD
-	}
-	if m.Truncated {
-		bits |= headerBitTC
-	}
-	if m.Authoritative {
-		bits |= headerBitAA
-	}
-	if m.Response {
-		bits |= headerBitQR
-	}
-	return
-}
-
-// GoString implements fmt.GoStringer.GoString.
-func (m *Header) GoString() string {
-	return "dnsmessage.Header{" +
-		"ID: " + printUint16(m.ID) + ", " +
-		"Response: " + printBool(m.Response) + ", " +
-		"OpCode: " + m.OpCode.GoString() + ", " +
-		"Authoritative: " + printBool(m.Authoritative) + ", " +
-		"Truncated: " + printBool(m.Truncated) + ", " +
-		"RecursionDesired: " + printBool(m.RecursionDesired) + ", " +
-		"RecursionAvailable: " + printBool(m.RecursionAvailable) + ", " +
-		"RCode: " + m.RCode.GoString() + "}"
-}
-
-// Message is a representation of a DNS message.
-type Message struct {
-	Header
-	Questions   []Question
-	Answers     []Resource
-	Authorities []Resource
-	Additionals []Resource
-}
-
-type section uint8
-
-const (
-	sectionNotStarted section = iota
-	sectionHeader
-	sectionQuestions
-	sectionAnswers
-	sectionAuthorities
-	sectionAdditionals
-	sectionDone
-
-	headerBitQR = 1 << 15 // query/response (response=1)
-	headerBitAA = 1 << 10 // authoritative
-	headerBitTC = 1 << 9  // truncated
-	headerBitRD = 1 << 8  // recursion desired
-	headerBitRA = 1 << 7  // recursion available
-)
-
-var sectionNames = map[section]string{
-	sectionHeader:      "header",
-	sectionQuestions:   "Question",
-	sectionAnswers:     "Answer",
-	sectionAuthorities: "Authority",
-	sectionAdditionals: "Additional",
-}
-
-// header is the wire format for a DNS message header.
-type header struct {
-	id          uint16
-	bits        uint16
-	questions   uint16
-	answers     uint16
-	authorities uint16
-	additionals uint16
-}
-
-func (h *header) count(sec section) uint16 {
-	switch sec {
-	case sectionQuestions:
-		return h.questions
-	case sectionAnswers:
-		return h.answers
-	case sectionAuthorities:
-		return h.authorities
-	case sectionAdditionals:
-		return h.additionals
-	}
-	return 0
-}
-
-// pack appends the wire format of the header to msg.
-func (h *header) pack(msg []byte) []byte {
-	msg = packUint16(msg, h.id)
-	msg = packUint16(msg, h.bits)
-	msg = packUint16(msg, h.questions)
-	msg = packUint16(msg, h.answers)
-	msg = packUint16(msg, h.authorities)
-	return packUint16(msg, h.additionals)
-}
-
-func (h *header) unpack(msg []byte, off int) (int, error) {
-	newOff := off
-	var err error
-	if h.id, newOff, err = unpackUint16(msg, newOff); err != nil {
-		return off, &nestedError{"id", err}
-	}
-	if h.bits, newOff, err = unpackUint16(msg, newOff); err != nil {
-		return off, &nestedError{"bits", err}
-	}
-	if h.questions, newOff, err = unpackUint16(msg, newOff); err != nil {
-		return off, &nestedError{"questions", err}
-	}
-	if h.answers, newOff, err = unpackUint16(msg, newOff); err != nil {
-		return off, &nestedError{"answers", err}
-	}
-	if h.authorities, newOff, err = unpackUint16(msg, newOff); err != nil {
-		return off, &nestedError{"authorities", err}
-	}
-	if h.additionals, newOff, err = unpackUint16(msg, newOff); err != nil {
-		return off, &nestedError{"additionals", err}
-	}
-	return newOff, nil
-}
-
-func (h *header) header() Header {
-	return Header{
-		ID:                 h.id,
-		Response:           (h.bits & headerBitQR) != 0,
-		OpCode:             OpCode(h.bits>>11) & 0xF,
-		Authoritative:      (h.bits & headerBitAA) != 0,
-		Truncated:          (h.bits & headerBitTC) != 0,
-		RecursionDesired:   (h.bits & headerBitRD) != 0,
-		RecursionAvailable: (h.bits & headerBitRA) != 0,
-		RCode:              RCode(h.bits & 0xF),
-	}
-}
-
-// A Resource is a DNS resource record.
-type Resource struct {
-	Header ResourceHeader
-	Body   ResourceBody
-}
-
-func (r *Resource) GoString() string {
-	return "dnsmessage.Resource{" +
-		"Header: " + r.Header.GoString() +
-		", Body: &" + r.Body.GoString() +
-		"}"
-}
-
-// A ResourceBody is a DNS resource record minus the header.
-type ResourceBody interface {
-	// pack packs a Resource except for its header.
-	pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error)
-
-	// realType returns the actual type of the Resource. This is used to
-	// fill in the header Type field.
-	realType() Type
-
-	// GoString implements fmt.GoStringer.GoString.
-	GoString() string
-}
-
-// pack appends the wire format of the Resource to msg.
-func (r *Resource) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
-	if r.Body == nil {
-		return msg, errNilResouceBody
-	}
-	oldMsg := msg
-	r.Header.Type = r.Body.realType()
-	msg, lenOff, err := r.Header.pack(msg, compression, compressionOff)
-	if err != nil {
-		return msg, &nestedError{"ResourceHeader", err}
-	}
-	preLen := len(msg)
-	msg, err = r.Body.pack(msg, compression, compressionOff)
-	if err != nil {
-		return msg, &nestedError{"content", err}
-	}
-	if err := r.Header.fixLen(msg, lenOff, preLen); err != nil {
-		return oldMsg, err
-	}
-	return msg, nil
-}
-
-// A Parser allows incrementally parsing a DNS message.
-//
-// When parsing is started, the Header is parsed. Next, each Question can be
-// either parsed or skipped. Alternatively, all Questions can be skipped at
-// once. When all Questions have been parsed, attempting to parse Questions
-// will return (nil, nil) and attempting to skip Questions will return
-// (true, nil). After all Questions have been either parsed or skipped, all
-// Answers, Authorities and Additionals can be either parsed or skipped in the
-// same way, and each type of Resource must be fully parsed or skipped before
-// proceeding to the next type of Resource.
-//
-// Note that there is no requirement to fully skip or parse the message.
-type Parser struct {
-	msg    []byte
-	header header
-
-	section        section
-	off            int
-	index          int
-	resHeaderValid bool
-	resHeader      ResourceHeader
-}
-
-// Start parses the header and enables the parsing of Questions.
-func (p *Parser) Start(msg []byte) (Header, error) {
-	if p.msg != nil {
-		*p = Parser{}
-	}
-	p.msg = msg
-	var err error
-	if p.off, err = p.header.unpack(msg, 0); err != nil {
-		return Header{}, &nestedError{"unpacking header", err}
-	}
-	p.section = sectionQuestions
-	return p.header.header(), nil
-}
-
-func (p *Parser) checkAdvance(sec section) error {
-	if p.section < sec {
-		return ErrNotStarted
-	}
-	if p.section > sec {
-		return ErrSectionDone
-	}
-	p.resHeaderValid = false
-	if p.index == int(p.header.count(sec)) {
-		p.index = 0
-		p.section++
-		return ErrSectionDone
-	}
-	return nil
-}
-
-func (p *Parser) resource(sec section) (Resource, error) {
-	var r Resource
-	var err error
-	r.Header, err = p.resourceHeader(sec)
-	if err != nil {
-		return r, err
-	}
-	p.resHeaderValid = false
-	r.Body, p.off, err = unpackResourceBody(p.msg, p.off, r.Header)
-	if err != nil {
-		return Resource{}, &nestedError{"unpacking " + sectionNames[sec], err}
-	}
-	p.index++
-	return r, nil
-}
-
-func (p *Parser) resourceHeader(sec section) (ResourceHeader, error) {
-	if p.resHeaderValid {
-		return p.resHeader, nil
-	}
-	if err := p.checkAdvance(sec); err != nil {
-		return ResourceHeader{}, err
-	}
-	var hdr ResourceHeader
-	off, err := hdr.unpack(p.msg, p.off)
-	if err != nil {
-		return ResourceHeader{}, err
-	}
-	p.resHeaderValid = true
-	p.resHeader = hdr
-	p.off = off
-	return hdr, nil
-}
-
-func (p *Parser) skipResource(sec section) error {
-	if p.resHeaderValid {
-		newOff := p.off + int(p.resHeader.Length)
-		if newOff > len(p.msg) {
-			return errResourceLen
-		}
-		p.off = newOff
-		p.resHeaderValid = false
-		p.index++
-		return nil
-	}
-	if err := p.checkAdvance(sec); err != nil {
-		return err
-	}
-	var err error
-	p.off, err = skipResource(p.msg, p.off)
-	if err != nil {
-		return &nestedError{"skipping: " + sectionNames[sec], err}
-	}
-	p.index++
-	return nil
-}
-
-// Question parses a single Question.
-func (p *Parser) Question() (Question, error) {
-	if err := p.checkAdvance(sectionQuestions); err != nil {
-		return Question{}, err
-	}
-	var name Name
-	off, err := name.unpack(p.msg, p.off)
-	if err != nil {
-		return Question{}, &nestedError{"unpacking Question.Name", err}
-	}
-	typ, off, err := unpackType(p.msg, off)
-	if err != nil {
-		return Question{}, &nestedError{"unpacking Question.Type", err}
-	}
-	class, off, err := unpackClass(p.msg, off)
-	if err != nil {
-		return Question{}, &nestedError{"unpacking Question.Class", err}
-	}
-	p.off = off
-	p.index++
-	return Question{name, typ, class}, nil
-}
-
-// AllQuestions parses all Questions.
-func (p *Parser) AllQuestions() ([]Question, error) {
-	// Multiple questions are valid according to the spec,
-	// but servers don't actually support them. There will
-	// be at most one question here.
-	//
-	// Do not pre-allocate based on info in p.header, since
-	// the data is untrusted.
-	qs := []Question{}
-	for {
-		q, err := p.Question()
-		if err == ErrSectionDone {
-			return qs, nil
-		}
-		if err != nil {
-			return nil, err
-		}
-		qs = append(qs, q)
-	}
-}
-
-// SkipQuestion skips a single Question.
-func (p *Parser) SkipQuestion() error {
-	if err := p.checkAdvance(sectionQuestions); err != nil {
-		return err
-	}
-	off, err := skipName(p.msg, p.off)
-	if err != nil {
-		return &nestedError{"skipping Question Name", err}
-	}
-	if off, err = skipType(p.msg, off); err != nil {
-		return &nestedError{"skipping Question Type", err}
-	}
-	if off, err = skipClass(p.msg, off); err != nil {
-		return &nestedError{"skipping Question Class", err}
-	}
-	p.off = off
-	p.index++
-	return nil
-}
-
-// SkipAllQuestions skips all Questions.
-func (p *Parser) SkipAllQuestions() error {
-	for {
-		if err := p.SkipQuestion(); err == ErrSectionDone {
-			return nil
-		} else if err != nil {
-			return err
-		}
-	}
-}
-
-// AnswerHeader parses a single Answer ResourceHeader.
-func (p *Parser) AnswerHeader() (ResourceHeader, error) {
-	return p.resourceHeader(sectionAnswers)
-}
-
-// Answer parses a single Answer Resource.
-func (p *Parser) Answer() (Resource, error) {
-	return p.resource(sectionAnswers)
-}
-
-// AllAnswers parses all Answer Resources.
-func (p *Parser) AllAnswers() ([]Resource, error) {
-	// The most common query is for A/AAAA, which usually returns
-	// a handful of IPs.
-	//
-	// Pre-allocate up to a certain limit, since p.header is
-	// untrusted data.
-	n := int(p.header.answers)
-	if n > 20 {
-		n = 20
-	}
-	as := make([]Resource, 0, n)
-	for {
-		a, err := p.Answer()
-		if err == ErrSectionDone {
-			return as, nil
-		}
-		if err != nil {
-			return nil, err
-		}
-		as = append(as, a)
-	}
-}
-
-// SkipAnswer skips a single Answer Resource.
-func (p *Parser) SkipAnswer() error {
-	return p.skipResource(sectionAnswers)
-}
-
-// SkipAllAnswers skips all Answer Resources.
-func (p *Parser) SkipAllAnswers() error {
-	for {
-		if err := p.SkipAnswer(); err == ErrSectionDone {
-			return nil
-		} else if err != nil {
-			return err
-		}
-	}
-}
-
-// AuthorityHeader parses a single Authority ResourceHeader.
-func (p *Parser) AuthorityHeader() (ResourceHeader, error) {
-	return p.resourceHeader(sectionAuthorities)
-}
-
-// Authority parses a single Authority Resource.
-func (p *Parser) Authority() (Resource, error) {
-	return p.resource(sectionAuthorities)
-}
-
-// AllAuthorities parses all Authority Resources.
-func (p *Parser) AllAuthorities() ([]Resource, error) {
-	// Authorities contains SOA in case of NXDOMAIN and friends,
-	// otherwise it is empty.
-	//
-	// Pre-allocate up to a certain limit, since p.header is
-	// untrusted data.
-	n := int(p.header.authorities)
-	if n > 10 {
-		n = 10
-	}
-	as := make([]Resource, 0, n)
-	for {
-		a, err := p.Authority()
-		if err == ErrSectionDone {
-			return as, nil
-		}
-		if err != nil {
-			return nil, err
-		}
-		as = append(as, a)
-	}
-}
-
-// SkipAuthority skips a single Authority Resource.
-func (p *Parser) SkipAuthority() error {
-	return p.skipResource(sectionAuthorities)
-}
-
-// SkipAllAuthorities skips all Authority Resources.
-func (p *Parser) SkipAllAuthorities() error {
-	for {
-		if err := p.SkipAuthority(); err == ErrSectionDone {
-			return nil
-		} else if err != nil {
-			return err
-		}
-	}
-}
-
-// AdditionalHeader parses a single Additional ResourceHeader.
-func (p *Parser) AdditionalHeader() (ResourceHeader, error) {
-	return p.resourceHeader(sectionAdditionals)
-}
-
-// Additional parses a single Additional Resource.
-func (p *Parser) Additional() (Resource, error) {
-	return p.resource(sectionAdditionals)
-}
-
-// AllAdditionals parses all Additional Resources.
-func (p *Parser) AllAdditionals() ([]Resource, error) {
-	// Additionals usually contain OPT, and sometimes A/AAAA
-	// glue records.
-	//
-	// Pre-allocate up to a certain limit, since p.header is
-	// untrusted data.
-	n := int(p.header.additionals)
-	if n > 10 {
-		n = 10
-	}
-	as := make([]Resource, 0, n)
-	for {
-		a, err := p.Additional()
-		if err == ErrSectionDone {
-			return as, nil
-		}
-		if err != nil {
-			return nil, err
-		}
-		as = append(as, a)
-	}
-}
-
-// SkipAdditional skips a single Additional Resource.
-func (p *Parser) SkipAdditional() error {
-	return p.skipResource(sectionAdditionals)
-}
-
-// SkipAllAdditionals skips all Additional Resources.
-func (p *Parser) SkipAllAdditionals() error {
-	for {
-		if err := p.SkipAdditional(); err == ErrSectionDone {
-			return nil
-		} else if err != nil {
-			return err
-		}
-	}
-}
-
-// CNAMEResource parses a single CNAMEResource.
-//
-// One of the XXXHeader methods must have been called before calling this
-// method.
-func (p *Parser) CNAMEResource() (CNAMEResource, error) {
-	if !p.resHeaderValid || p.resHeader.Type != TypeCNAME {
-		return CNAMEResource{}, ErrNotStarted
-	}
-	r, err := unpackCNAMEResource(p.msg, p.off)
-	if err != nil {
-		return CNAMEResource{}, err
-	}
-	p.off += int(p.resHeader.Length)
-	p.resHeaderValid = false
-	p.index++
-	return r, nil
-}
-
-// MXResource parses a single MXResource.
-//
-// One of the XXXHeader methods must have been called before calling this
-// method.
-func (p *Parser) MXResource() (MXResource, error) {
-	if !p.resHeaderValid || p.resHeader.Type != TypeMX {
-		return MXResource{}, ErrNotStarted
-	}
-	r, err := unpackMXResource(p.msg, p.off)
-	if err != nil {
-		return MXResource{}, err
-	}
-	p.off += int(p.resHeader.Length)
-	p.resHeaderValid = false
-	p.index++
-	return r, nil
-}
-
-// NSResource parses a single NSResource.
-//
-// One of the XXXHeader methods must have been called before calling this
-// method.
-func (p *Parser) NSResource() (NSResource, error) {
-	if !p.resHeaderValid || p.resHeader.Type != TypeNS {
-		return NSResource{}, ErrNotStarted
-	}
-	r, err := unpackNSResource(p.msg, p.off)
-	if err != nil {
-		return NSResource{}, err
-	}
-	p.off += int(p.resHeader.Length)
-	p.resHeaderValid = false
-	p.index++
-	return r, nil
-}
-
-// PTRResource parses a single PTRResource.
-//
-// One of the XXXHeader methods must have been called before calling this
-// method.
-func (p *Parser) PTRResource() (PTRResource, error) {
-	if !p.resHeaderValid || p.resHeader.Type != TypePTR {
-		return PTRResource{}, ErrNotStarted
-	}
-	r, err := unpackPTRResource(p.msg, p.off)
-	if err != nil {
-		return PTRResource{}, err
-	}
-	p.off += int(p.resHeader.Length)
-	p.resHeaderValid = false
-	p.index++
-	return r, nil
-}
-
-// SOAResource parses a single SOAResource.
-//
-// One of the XXXHeader methods must have been called before calling this
-// method.
-func (p *Parser) SOAResource() (SOAResource, error) {
-	if !p.resHeaderValid || p.resHeader.Type != TypeSOA {
-		return SOAResource{}, ErrNotStarted
-	}
-	r, err := unpackSOAResource(p.msg, p.off)
-	if err != nil {
-		return SOAResource{}, err
-	}
-	p.off += int(p.resHeader.Length)
-	p.resHeaderValid = false
-	p.index++
-	return r, nil
-}
-
-// TXTResource parses a single TXTResource.
-//
-// One of the XXXHeader methods must have been called before calling this
-// method.
-func (p *Parser) TXTResource() (TXTResource, error) {
-	if !p.resHeaderValid || p.resHeader.Type != TypeTXT {
-		return TXTResource{}, ErrNotStarted
-	}
-	r, err := unpackTXTResource(p.msg, p.off, p.resHeader.Length)
-	if err != nil {
-		return TXTResource{}, err
-	}
-	p.off += int(p.resHeader.Length)
-	p.resHeaderValid = false
-	p.index++
-	return r, nil
-}
-
-// SRVResource parses a single SRVResource.
-//
-// One of the XXXHeader methods must have been called before calling this
-// method.
-func (p *Parser) SRVResource() (SRVResource, error) {
-	if !p.resHeaderValid || p.resHeader.Type != TypeSRV {
-		return SRVResource{}, ErrNotStarted
-	}
-	r, err := unpackSRVResource(p.msg, p.off)
-	if err != nil {
-		return SRVResource{}, err
-	}
-	p.off += int(p.resHeader.Length)
-	p.resHeaderValid = false
-	p.index++
-	return r, nil
-}
-
-// AResource parses a single AResource.
-//
-// One of the XXXHeader methods must have been called before calling this
-// method.
-func (p *Parser) AResource() (AResource, error) {
-	if !p.resHeaderValid || p.resHeader.Type != TypeA {
-		return AResource{}, ErrNotStarted
-	}
-	r, err := unpackAResource(p.msg, p.off)
-	if err != nil {
-		return AResource{}, err
-	}
-	p.off += int(p.resHeader.Length)
-	p.resHeaderValid = false
-	p.index++
-	return r, nil
-}
-
-// AAAAResource parses a single AAAAResource.
-//
-// One of the XXXHeader methods must have been called before calling this
-// method.
-func (p *Parser) AAAAResource() (AAAAResource, error) {
-	if !p.resHeaderValid || p.resHeader.Type != TypeAAAA {
-		return AAAAResource{}, ErrNotStarted
-	}
-	r, err := unpackAAAAResource(p.msg, p.off)
-	if err != nil {
-		return AAAAResource{}, err
-	}
-	p.off += int(p.resHeader.Length)
-	p.resHeaderValid = false
-	p.index++
-	return r, nil
-}
-
-// OPTResource parses a single OPTResource.
-//
-// One of the XXXHeader methods must have been called before calling this
-// method.
-func (p *Parser) OPTResource() (OPTResource, error) {
-	if !p.resHeaderValid || p.resHeader.Type != TypeOPT {
-		return OPTResource{}, ErrNotStarted
-	}
-	r, err := unpackOPTResource(p.msg, p.off, p.resHeader.Length)
-	if err != nil {
-		return OPTResource{}, err
-	}
-	p.off += int(p.resHeader.Length)
-	p.resHeaderValid = false
-	p.index++
-	return r, nil
-}
-
-// UnknownResource parses a single UnknownResource.
-//
-// One of the XXXHeader methods must have been called before calling this
-// method.
-func (p *Parser) UnknownResource() (UnknownResource, error) {
-	if !p.resHeaderValid {
-		return UnknownResource{}, ErrNotStarted
-	}
-	r, err := unpackUnknownResource(p.resHeader.Type, p.msg, p.off, p.resHeader.Length)
-	if err != nil {
-		return UnknownResource{}, err
-	}
-	p.off += int(p.resHeader.Length)
-	p.resHeaderValid = false
-	p.index++
-	return r, nil
-}
-
-// Unpack parses a full Message.
-func (m *Message) Unpack(msg []byte) error {
-	var p Parser
-	var err error
-	if m.Header, err = p.Start(msg); err != nil {
-		return err
-	}
-	if m.Questions, err = p.AllQuestions(); err != nil {
-		return err
-	}
-	if m.Answers, err = p.AllAnswers(); err != nil {
-		return err
-	}
-	if m.Authorities, err = p.AllAuthorities(); err != nil {
-		return err
-	}
-	if m.Additionals, err = p.AllAdditionals(); err != nil {
-		return err
-	}
-	return nil
-}
-
-// Pack packs a full Message.
-func (m *Message) Pack() ([]byte, error) {
-	return m.AppendPack(make([]byte, 0, packStartingCap))
-}
-
-// AppendPack is like Pack but appends the full Message to b and returns the
-// extended buffer.
-func (m *Message) AppendPack(b []byte) ([]byte, error) {
-	// Validate the lengths. It is very unlikely that anyone will try to
-	// pack more than 65535 of any particular type, but it is possible and
-	// we should fail gracefully.
-	if len(m.Questions) > int(^uint16(0)) {
-		return nil, errTooManyQuestions
-	}
-	if len(m.Answers) > int(^uint16(0)) {
-		return nil, errTooManyAnswers
-	}
-	if len(m.Authorities) > int(^uint16(0)) {
-		return nil, errTooManyAuthorities
-	}
-	if len(m.Additionals) > int(^uint16(0)) {
-		return nil, errTooManyAdditionals
-	}
-
-	var h header
-	h.id, h.bits = m.Header.pack()
-
-	h.questions = uint16(len(m.Questions))
-	h.answers = uint16(len(m.Answers))
-	h.authorities = uint16(len(m.Authorities))
-	h.additionals = uint16(len(m.Additionals))
-
-	compressionOff := len(b)
-	msg := h.pack(b)
-
-	// RFC 1035 allows (but does not require) compression for packing. RFC
-	// 1035 requires unpacking implementations to support compression, so
-	// unconditionally enabling it is fine.
-	//
-	// DNS lookups are typically done over UDP, and RFC 1035 states that UDP
-	// DNS messages can be a maximum of 512 bytes long. Without compression,
-	// many DNS response messages are over this limit, so enabling
-	// compression will help ensure compliance.
-	compression := map[string]int{}
-
-	for i := range m.Questions {
-		var err error
-		if msg, err = m.Questions[i].pack(msg, compression, compressionOff); err != nil {
-			return nil, &nestedError{"packing Question", err}
-		}
-	}
-	for i := range m.Answers {
-		var err error
-		if msg, err = m.Answers[i].pack(msg, compression, compressionOff); err != nil {
-			return nil, &nestedError{"packing Answer", err}
-		}
-	}
-	for i := range m.Authorities {
-		var err error
-		if msg, err = m.Authorities[i].pack(msg, compression, compressionOff); err != nil {
-			return nil, &nestedError{"packing Authority", err}
-		}
-	}
-	for i := range m.Additionals {
-		var err error
-		if msg, err = m.Additionals[i].pack(msg, compression, compressionOff); err != nil {
-			return nil, &nestedError{"packing Additional", err}
-		}
-	}
-
-	return msg, nil
-}
-
-// GoString implements fmt.GoStringer.GoString.
-func (m *Message) GoString() string {
-	s := "dnsmessage.Message{Header: " + m.Header.GoString() + ", " +
-		"Questions: []dnsmessage.Question{"
-	if len(m.Questions) > 0 {
-		s += m.Questions[0].GoString()
-		for _, q := range m.Questions[1:] {
-			s += ", " + q.GoString()
-		}
-	}
-	s += "}, Answers: []dnsmessage.Resource{"
-	if len(m.Answers) > 0 {
-		s += m.Answers[0].GoString()
-		for _, a := range m.Answers[1:] {
-			s += ", " + a.GoString()
-		}
-	}
-	s += "}, Authorities: []dnsmessage.Resource{"
-	if len(m.Authorities) > 0 {
-		s += m.Authorities[0].GoString()
-		for _, a := range m.Authorities[1:] {
-			s += ", " + a.GoString()
-		}
-	}
-	s += "}, Additionals: []dnsmessage.Resource{"
-	if len(m.Additionals) > 0 {
-		s += m.Additionals[0].GoString()
-		for _, a := range m.Additionals[1:] {
-			s += ", " + a.GoString()
-		}
-	}
-	return s + "}}"
-}
-
-// A Builder allows incrementally packing a DNS message.
-//
-// Example usage:
-//	buf := make([]byte, 2, 514)
-//	b := NewBuilder(buf, Header{...})
-//	b.EnableCompression()
-//	// Optionally start a section and add things to that section.
-//	// Repeat adding sections as necessary.
-//	buf, err := b.Finish()
-//	// If err is nil, buf[2:] will contain the built bytes.
-type Builder struct {
-	// msg is the storage for the message being built.
-	msg []byte
-
-	// section keeps track of the current section being built.
-	section section
-
-	// header keeps track of what should go in the header when Finish is
-	// called.
-	header header
-
-	// start is the starting index of the bytes allocated in msg for header.
-	start int
-
-	// compression is a mapping from name suffixes to their starting index
-	// in msg.
-	compression map[string]int
-}
-
-// NewBuilder creates a new builder with compression disabled.
-//
-// Note: Most users will want to immediately enable compression with the
-// EnableCompression method. See that method's comment for why you may or may
-// not want to enable compression.
-//
-// The DNS message is appended to the provided initial buffer buf (which may be
-// nil) as it is built. The final message is returned by the (*Builder).Finish
-// method, which includes buf[:len(buf)] and may return the same underlying
-// array if there was sufficient capacity in the slice.
-func NewBuilder(buf []byte, h Header) Builder {
-	if buf == nil {
-		buf = make([]byte, 0, packStartingCap)
-	}
-	b := Builder{msg: buf, start: len(buf)}
-	b.header.id, b.header.bits = h.pack()
-	var hb [headerLen]byte
-	b.msg = append(b.msg, hb[:]...)
-	b.section = sectionHeader
-	return b
-}
-
-// EnableCompression enables compression in the Builder.
-//
-// Leaving compression disabled avoids compression related allocations, but can
-// result in larger message sizes. Be careful with this mode as it can cause
-// messages to exceed the UDP size limit.
-//
-// According to RFC 1035, section 4.1.4, the use of compression is optional, but
-// all implementations must accept both compressed and uncompressed DNS
-// messages.
-//
-// Compression should be enabled before any sections are added for best results.
-func (b *Builder) EnableCompression() {
-	b.compression = map[string]int{}
-}
-
-func (b *Builder) startCheck(s section) error {
-	if b.section <= sectionNotStarted {
-		return ErrNotStarted
-	}
-	if b.section > s {
-		return ErrSectionDone
-	}
-	return nil
-}
-
-// StartQuestions prepares the builder for packing Questions.
-func (b *Builder) StartQuestions() error {
-	if err := b.startCheck(sectionQuestions); err != nil {
-		return err
-	}
-	b.section = sectionQuestions
-	return nil
-}
-
-// StartAnswers prepares the builder for packing Answers.
-func (b *Builder) StartAnswers() error {
-	if err := b.startCheck(sectionAnswers); err != nil {
-		return err
-	}
-	b.section = sectionAnswers
-	return nil
-}
-
-// StartAuthorities prepares the builder for packing Authorities.
-func (b *Builder) StartAuthorities() error {
-	if err := b.startCheck(sectionAuthorities); err != nil {
-		return err
-	}
-	b.section = sectionAuthorities
-	return nil
-}
-
-// StartAdditionals prepares the builder for packing Additionals.
-func (b *Builder) StartAdditionals() error {
-	if err := b.startCheck(sectionAdditionals); err != nil {
-		return err
-	}
-	b.section = sectionAdditionals
-	return nil
-}
-
-func (b *Builder) incrementSectionCount() error {
-	var count *uint16
-	var err error
-	switch b.section {
-	case sectionQuestions:
-		count = &b.header.questions
-		err = errTooManyQuestions
-	case sectionAnswers:
-		count = &b.header.answers
-		err = errTooManyAnswers
-	case sectionAuthorities:
-		count = &b.header.authorities
-		err = errTooManyAuthorities
-	case sectionAdditionals:
-		count = &b.header.additionals
-		err = errTooManyAdditionals
-	}
-	if *count == ^uint16(0) {
-		return err
-	}
-	*count++
-	return nil
-}
-
-// Question adds a single Question.
-func (b *Builder) Question(q Question) error {
-	if b.section < sectionQuestions {
-		return ErrNotStarted
-	}
-	if b.section > sectionQuestions {
-		return ErrSectionDone
-	}
-	msg, err := q.pack(b.msg, b.compression, b.start)
-	if err != nil {
-		return err
-	}
-	if err := b.incrementSectionCount(); err != nil {
-		return err
-	}
-	b.msg = msg
-	return nil
-}
-
-func (b *Builder) checkResourceSection() error {
-	if b.section < sectionAnswers {
-		return ErrNotStarted
-	}
-	if b.section > sectionAdditionals {
-		return ErrSectionDone
-	}
-	return nil
-}
-
-// CNAMEResource adds a single CNAMEResource.
-func (b *Builder) CNAMEResource(h ResourceHeader, r CNAMEResource) error {
-	if err := b.checkResourceSection(); err != nil {
-		return err
-	}
-	h.Type = r.realType()
-	msg, lenOff, err := h.pack(b.msg, b.compression, b.start)
-	if err != nil {
-		return &nestedError{"ResourceHeader", err}
-	}
-	preLen := len(msg)
-	if msg, err = r.pack(msg, b.compression, b.start); err != nil {
-		return &nestedError{"CNAMEResource body", err}
-	}
-	if err := h.fixLen(msg, lenOff, preLen); err != nil {
-		return err
-	}
-	if err := b.incrementSectionCount(); err != nil {
-		return err
-	}
-	b.msg = msg
-	return nil
-}
-
-// MXResource adds a single MXResource.
-func (b *Builder) MXResource(h ResourceHeader, r MXResource) error {
-	if err := b.checkResourceSection(); err != nil {
-		return err
-	}
-	h.Type = r.realType()
-	msg, lenOff, err := h.pack(b.msg, b.compression, b.start)
-	if err != nil {
-		return &nestedError{"ResourceHeader", err}
-	}
-	preLen := len(msg)
-	if msg, err = r.pack(msg, b.compression, b.start); err != nil {
-		return &nestedError{"MXResource body", err}
-	}
-	if err := h.fixLen(msg, lenOff, preLen); err != nil {
-		return err
-	}
-	if err := b.incrementSectionCount(); err != nil {
-		return err
-	}
-	b.msg = msg
-	return nil
-}
-
-// NSResource adds a single NSResource.
-func (b *Builder) NSResource(h ResourceHeader, r NSResource) error {
-	if err := b.checkResourceSection(); err != nil {
-		return err
-	}
-	h.Type = r.realType()
-	msg, lenOff, err := h.pack(b.msg, b.compression, b.start)
-	if err != nil {
-		return &nestedError{"ResourceHeader", err}
-	}
-	preLen := len(msg)
-	if msg, err = r.pack(msg, b.compression, b.start); err != nil {
-		return &nestedError{"NSResource body", err}
-	}
-	if err := h.fixLen(msg, lenOff, preLen); err != nil {
-		return err
-	}
-	if err := b.incrementSectionCount(); err != nil {
-		return err
-	}
-	b.msg = msg
-	return nil
-}
-
-// PTRResource adds a single PTRResource.
-func (b *Builder) PTRResource(h ResourceHeader, r PTRResource) error {
-	if err := b.checkResourceSection(); err != nil {
-		return err
-	}
-	h.Type = r.realType()
-	msg, lenOff, err := h.pack(b.msg, b.compression, b.start)
-	if err != nil {
-		return &nestedError{"ResourceHeader", err}
-	}
-	preLen := len(msg)
-	if msg, err = r.pack(msg, b.compression, b.start); err != nil {
-		return &nestedError{"PTRResource body", err}
-	}
-	if err := h.fixLen(msg, lenOff, preLen); err != nil {
-		return err
-	}
-	if err := b.incrementSectionCount(); err != nil {
-		return err
-	}
-	b.msg = msg
-	return nil
-}
-
-// SOAResource adds a single SOAResource.
-func (b *Builder) SOAResource(h ResourceHeader, r SOAResource) error {
-	if err := b.checkResourceSection(); err != nil {
-		return err
-	}
-	h.Type = r.realType()
-	msg, lenOff, err := h.pack(b.msg, b.compression, b.start)
-	if err != nil {
-		return &nestedError{"ResourceHeader", err}
-	}
-	preLen := len(msg)
-	if msg, err = r.pack(msg, b.compression, b.start); err != nil {
-		return &nestedError{"SOAResource body", err}
-	}
-	if err := h.fixLen(msg, lenOff, preLen); err != nil {
-		return err
-	}
-	if err := b.incrementSectionCount(); err != nil {
-		return err
-	}
-	b.msg = msg
-	return nil
-}
-
-// TXTResource adds a single TXTResource.
-func (b *Builder) TXTResource(h ResourceHeader, r TXTResource) error {
-	if err := b.checkResourceSection(); err != nil {
-		return err
-	}
-	h.Type = r.realType()
-	msg, lenOff, err := h.pack(b.msg, b.compression, b.start)
-	if err != nil {
-		return &nestedError{"ResourceHeader", err}
-	}
-	preLen := len(msg)
-	if msg, err = r.pack(msg, b.compression, b.start); err != nil {
-		return &nestedError{"TXTResource body", err}
-	}
-	if err := h.fixLen(msg, lenOff, preLen); err != nil {
-		return err
-	}
-	if err := b.incrementSectionCount(); err != nil {
-		return err
-	}
-	b.msg = msg
-	return nil
-}
-
-// SRVResource adds a single SRVResource.
-func (b *Builder) SRVResource(h ResourceHeader, r SRVResource) error {
-	if err := b.checkResourceSection(); err != nil {
-		return err
-	}
-	h.Type = r.realType()
-	msg, lenOff, err := h.pack(b.msg, b.compression, b.start)
-	if err != nil {
-		return &nestedError{"ResourceHeader", err}
-	}
-	preLen := len(msg)
-	if msg, err = r.pack(msg, b.compression, b.start); err != nil {
-		return &nestedError{"SRVResource body", err}
-	}
-	if err := h.fixLen(msg, lenOff, preLen); err != nil {
-		return err
-	}
-	if err := b.incrementSectionCount(); err != nil {
-		return err
-	}
-	b.msg = msg
-	return nil
-}
-
-// AResource adds a single AResource.
-func (b *Builder) AResource(h ResourceHeader, r AResource) error {
-	if err := b.checkResourceSection(); err != nil {
-		return err
-	}
-	h.Type = r.realType()
-	msg, lenOff, err := h.pack(b.msg, b.compression, b.start)
-	if err != nil {
-		return &nestedError{"ResourceHeader", err}
-	}
-	preLen := len(msg)
-	if msg, err = r.pack(msg, b.compression, b.start); err != nil {
-		return &nestedError{"AResource body", err}
-	}
-	if err := h.fixLen(msg, lenOff, preLen); err != nil {
-		return err
-	}
-	if err := b.incrementSectionCount(); err != nil {
-		return err
-	}
-	b.msg = msg
-	return nil
-}
-
-// AAAAResource adds a single AAAAResource.
-func (b *Builder) AAAAResource(h ResourceHeader, r AAAAResource) error {
-	if err := b.checkResourceSection(); err != nil {
-		return err
-	}
-	h.Type = r.realType()
-	msg, lenOff, err := h.pack(b.msg, b.compression, b.start)
-	if err != nil {
-		return &nestedError{"ResourceHeader", err}
-	}
-	preLen := len(msg)
-	if msg, err = r.pack(msg, b.compression, b.start); err != nil {
-		return &nestedError{"AAAAResource body", err}
-	}
-	if err := h.fixLen(msg, lenOff, preLen); err != nil {
-		return err
-	}
-	if err := b.incrementSectionCount(); err != nil {
-		return err
-	}
-	b.msg = msg
-	return nil
-}
-
-// OPTResource adds a single OPTResource.
-func (b *Builder) OPTResource(h ResourceHeader, r OPTResource) error {
-	if err := b.checkResourceSection(); err != nil {
-		return err
-	}
-	h.Type = r.realType()
-	msg, lenOff, err := h.pack(b.msg, b.compression, b.start)
-	if err != nil {
-		return &nestedError{"ResourceHeader", err}
-	}
-	preLen := len(msg)
-	if msg, err = r.pack(msg, b.compression, b.start); err != nil {
-		return &nestedError{"OPTResource body", err}
-	}
-	if err := h.fixLen(msg, lenOff, preLen); err != nil {
-		return err
-	}
-	if err := b.incrementSectionCount(); err != nil {
-		return err
-	}
-	b.msg = msg
-	return nil
-}
-
-// UnknownResource adds a single UnknownResource.
-func (b *Builder) UnknownResource(h ResourceHeader, r UnknownResource) error {
-	if err := b.checkResourceSection(); err != nil {
-		return err
-	}
-	h.Type = r.realType()
-	msg, lenOff, err := h.pack(b.msg, b.compression, b.start)
-	if err != nil {
-		return &nestedError{"ResourceHeader", err}
-	}
-	preLen := len(msg)
-	if msg, err = r.pack(msg, b.compression, b.start); err != nil {
-		return &nestedError{"UnknownResource body", err}
-	}
-	if err := h.fixLen(msg, lenOff, preLen); err != nil {
-		return err
-	}
-	if err := b.incrementSectionCount(); err != nil {
-		return err
-	}
-	b.msg = msg
-	return nil
-}
-
-// Finish ends message building and generates a binary message.
-func (b *Builder) Finish() ([]byte, error) {
-	if b.section < sectionHeader {
-		return nil, ErrNotStarted
-	}
-	b.section = sectionDone
-	// Space for the header was allocated in NewBuilder.
-	b.header.pack(b.msg[b.start:b.start])
-	return b.msg, nil
-}
-
-// A ResourceHeader is the header of a DNS resource record. There are
-// many types of DNS resource records, but they all share the same header.
-type ResourceHeader struct {
-	// Name is the domain name for which this resource record pertains.
-	Name Name
-
-	// Type is the type of DNS resource record.
-	//
-	// This field will be set automatically during packing.
-	Type Type
-
-	// Class is the class of network to which this DNS resource record
-	// pertains.
-	Class Class
-
-	// TTL is the length of time (measured in seconds) which this resource
-	// record is valid for (time to live). All Resources in a set should
-	// have the same TTL (RFC 2181 Section 5.2).
-	TTL uint32
-
-	// Length is the length of data in the resource record after the header.
-	//
-	// This field will be set automatically during packing.
-	Length uint16
-}
-
-// GoString implements fmt.GoStringer.GoString.
-func (h *ResourceHeader) GoString() string {
-	return "dnsmessage.ResourceHeader{" +
-		"Name: " + h.Name.GoString() + ", " +
-		"Type: " + h.Type.GoString() + ", " +
-		"Class: " + h.Class.GoString() + ", " +
-		"TTL: " + printUint32(h.TTL) + ", " +
-		"Length: " + printUint16(h.Length) + "}"
-}
-
-// pack appends the wire format of the ResourceHeader to oldMsg.
-//
-// lenOff is the offset in msg where the Length field was packed.
-func (h *ResourceHeader) pack(oldMsg []byte, compression map[string]int, compressionOff int) (msg []byte, lenOff int, err error) {
-	msg = oldMsg
-	if msg, err = h.Name.pack(msg, compression, compressionOff); err != nil {
-		return oldMsg, 0, &nestedError{"Name", err}
-	}
-	msg = packType(msg, h.Type)
-	msg = packClass(msg, h.Class)
-	msg = packUint32(msg, h.TTL)
-	lenOff = len(msg)
-	msg = packUint16(msg, h.Length)
-	return msg, lenOff, nil
-}
-
-func (h *ResourceHeader) unpack(msg []byte, off int) (int, error) {
-	newOff := off
-	var err error
-	if newOff, err = h.Name.unpack(msg, newOff); err != nil {
-		return off, &nestedError{"Name", err}
-	}
-	if h.Type, newOff, err = unpackType(msg, newOff); err != nil {
-		return off, &nestedError{"Type", err}
-	}
-	if h.Class, newOff, err = unpackClass(msg, newOff); err != nil {
-		return off, &nestedError{"Class", err}
-	}
-	if h.TTL, newOff, err = unpackUint32(msg, newOff); err != nil {
-		return off, &nestedError{"TTL", err}
-	}
-	if h.Length, newOff, err = unpackUint16(msg, newOff); err != nil {
-		return off, &nestedError{"Length", err}
-	}
-	return newOff, nil
-}
-
-// fixLen updates a packed ResourceHeader to include the length of the
-// ResourceBody.
-//
-// lenOff is the offset of the ResourceHeader.Length field in msg.
-//
-// preLen is the length that msg was before the ResourceBody was packed.
-func (h *ResourceHeader) fixLen(msg []byte, lenOff int, preLen int) error {
-	conLen := len(msg) - preLen
-	if conLen > int(^uint16(0)) {
-		return errResTooLong
-	}
-
-	// Fill in the length now that we know how long the content is.
-	packUint16(msg[lenOff:lenOff], uint16(conLen))
-	h.Length = uint16(conLen)
-
-	return nil
-}
-
-// EDNS(0) wire constants.
-const (
-	edns0Version = 0
-
-	edns0DNSSECOK     = 0x00008000
-	ednsVersionMask   = 0x00ff0000
-	edns0DNSSECOKMask = 0x00ff8000
-)
-
-// SetEDNS0 configures h for EDNS(0).
-//
-// The provided extRCode must be an extended RCode.
-func (h *ResourceHeader) SetEDNS0(udpPayloadLen int, extRCode RCode, dnssecOK bool) error {
-	h.Name = Name{Data: [nameLen]byte{'.'}, Length: 1} // RFC 6891 section 6.1.2
-	h.Type = TypeOPT
-	h.Class = Class(udpPayloadLen)
-	h.TTL = uint32(extRCode) >> 4 << 24
-	if dnssecOK {
-		h.TTL |= edns0DNSSECOK
-	}
-	return nil
-}
-
-// DNSSECAllowed reports whether the DNSSEC OK bit is set.
-func (h *ResourceHeader) DNSSECAllowed() bool {
-	return h.TTL&edns0DNSSECOKMask == edns0DNSSECOK // RFC 6891 section 6.1.3
-}
-
-// ExtendedRCode returns an extended RCode.
-//
-// The provided rcode must be the RCode in DNS message header.
-func (h *ResourceHeader) ExtendedRCode(rcode RCode) RCode {
-	if h.TTL&ednsVersionMask == edns0Version { // RFC 6891 section 6.1.3
-		return RCode(h.TTL>>24<<4) | rcode
-	}
-	return rcode
-}
-
-func skipResource(msg []byte, off int) (int, error) {
-	newOff, err := skipName(msg, off)
-	if err != nil {
-		return off, &nestedError{"Name", err}
-	}
-	if newOff, err = skipType(msg, newOff); err != nil {
-		return off, &nestedError{"Type", err}
-	}
-	if newOff, err = skipClass(msg, newOff); err != nil {
-		return off, &nestedError{"Class", err}
-	}
-	if newOff, err = skipUint32(msg, newOff); err != nil {
-		return off, &nestedError{"TTL", err}
-	}
-	length, newOff, err := unpackUint16(msg, newOff)
-	if err != nil {
-		return off, &nestedError{"Length", err}
-	}
-	if newOff += int(length); newOff > len(msg) {
-		return off, errResourceLen
-	}
-	return newOff, nil
-}
-
-// packUint16 appends the wire format of field to msg.
-func packUint16(msg []byte, field uint16) []byte {
-	return append(msg, byte(field>>8), byte(field))
-}
-
-func unpackUint16(msg []byte, off int) (uint16, int, error) {
-	if off+uint16Len > len(msg) {
-		return 0, off, errBaseLen
-	}
-	return uint16(msg[off])<<8 | uint16(msg[off+1]), off + uint16Len, nil
-}
-
-func skipUint16(msg []byte, off int) (int, error) {
-	if off+uint16Len > len(msg) {
-		return off, errBaseLen
-	}
-	return off + uint16Len, nil
-}
-
-// packType appends the wire format of field to msg.
-func packType(msg []byte, field Type) []byte {
-	return packUint16(msg, uint16(field))
-}
-
-func unpackType(msg []byte, off int) (Type, int, error) {
-	t, o, err := unpackUint16(msg, off)
-	return Type(t), o, err
-}
-
-func skipType(msg []byte, off int) (int, error) {
-	return skipUint16(msg, off)
-}
-
-// packClass appends the wire format of field to msg.
-func packClass(msg []byte, field Class) []byte {
-	return packUint16(msg, uint16(field))
-}
-
-func unpackClass(msg []byte, off int) (Class, int, error) {
-	c, o, err := unpackUint16(msg, off)
-	return Class(c), o, err
-}
-
-func skipClass(msg []byte, off int) (int, error) {
-	return skipUint16(msg, off)
-}
-
-// packUint32 appends the wire format of field to msg.
-func packUint32(msg []byte, field uint32) []byte {
-	return append(
-		msg,
-		byte(field>>24),
-		byte(field>>16),
-		byte(field>>8),
-		byte(field),
-	)
-}
-
-func unpackUint32(msg []byte, off int) (uint32, int, error) {
-	if off+uint32Len > len(msg) {
-		return 0, off, errBaseLen
-	}
-	v := uint32(msg[off])<<24 | uint32(msg[off+1])<<16 | uint32(msg[off+2])<<8 | uint32(msg[off+3])
-	return v, off + uint32Len, nil
-}
-
-func skipUint32(msg []byte, off int) (int, error) {
-	if off+uint32Len > len(msg) {
-		return off, errBaseLen
-	}
-	return off + uint32Len, nil
-}
-
-// packText appends the wire format of field to msg.
-func packText(msg []byte, field string) ([]byte, error) {
-	l := len(field)
-	if l > 255 {
-		return nil, errStringTooLong
-	}
-	msg = append(msg, byte(l))
-	msg = append(msg, field...)
-
-	return msg, nil
-}
-
-func unpackText(msg []byte, off int) (string, int, error) {
-	if off >= len(msg) {
-		return "", off, errBaseLen
-	}
-	beginOff := off + 1
-	endOff := beginOff + int(msg[off])
-	if endOff > len(msg) {
-		return "", off, errCalcLen
-	}
-	return string(msg[beginOff:endOff]), endOff, nil
-}
-
-// packBytes appends the wire format of field to msg.
-func packBytes(msg []byte, field []byte) []byte {
-	return append(msg, field...)
-}
-
-func unpackBytes(msg []byte, off int, field []byte) (int, error) {
-	newOff := off + len(field)
-	if newOff > len(msg) {
-		return off, errBaseLen
-	}
-	copy(field, msg[off:newOff])
-	return newOff, nil
-}
-
-const nameLen = 255
-
-// A Name is a non-encoded domain name. It is used instead of strings to avoid
-// allocations.
-type Name struct {
-	Data   [nameLen]byte // 255 bytes
-	Length uint8
-}
-
-// NewName creates a new Name from a string.
-func NewName(name string) (Name, error) {
-	if len([]byte(name)) > nameLen {
-		return Name{}, errCalcLen
-	}
-	n := Name{Length: uint8(len(name))}
-	copy(n.Data[:], []byte(name))
-	return n, nil
-}
-
-// MustNewName creates a new Name from a string and panics on error.
-func MustNewName(name string) Name {
-	n, err := NewName(name)
-	if err != nil {
-		panic("creating name: " + err.Error())
-	}
-	return n
-}
-
-// String implements fmt.Stringer.String.
-func (n Name) String() string {
-	return string(n.Data[:n.Length])
-}
-
-// GoString implements fmt.GoStringer.GoString.
-func (n *Name) GoString() string {
-	return `dnsmessage.MustNewName("` + printString(n.Data[:n.Length]) + `")`
-}
-
-// pack appends the wire format of the Name to msg.
-//
-// Domain names are a sequence of counted strings split at the dots. They end
-// with a zero-length string. Compression can be used to reuse domain suffixes.
-//
-// The compression map will be updated with new domain suffixes. If compression
-// is nil, compression will not be used.
-func (n *Name) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
-	oldMsg := msg
-
-	// Add a trailing dot to canonicalize name.
-	if n.Length == 0 || n.Data[n.Length-1] != '.' {
-		return oldMsg, errNonCanonicalName
-	}
-
-	// Allow root domain.
-	if n.Data[0] == '.' && n.Length == 1 {
-		return append(msg, 0), nil
-	}
-
-	// Emit sequence of counted strings, chopping at dots.
-	for i, begin := 0, 0; i < int(n.Length); i++ {
-		// Check for the end of the segment.
-		if n.Data[i] == '.' {
-			// The two most significant bits have special meaning.
-			// It isn't allowed for segments to be long enough to
-			// need them.
-			if i-begin >= 1<<6 {
-				return oldMsg, errSegTooLong
-			}
-
-			// Segments must have a non-zero length.
-			if i-begin == 0 {
-				return oldMsg, errZeroSegLen
-			}
-
-			msg = append(msg, byte(i-begin))
-
-			for j := begin; j < i; j++ {
-				msg = append(msg, n.Data[j])
-			}
-
-			begin = i + 1
-			continue
-		}
-
-		// We can only compress domain suffixes starting with a new
-		// segment. A pointer is two bytes with the two most significant
-		// bits set to 1 to indicate that it is a pointer.
-		if (i == 0 || n.Data[i-1] == '.') && compression != nil {
-			if ptr, ok := compression[string(n.Data[i:])]; ok {
-				// Hit. Emit a pointer instead of the rest of
-				// the domain.
-				return append(msg, byte(ptr>>8|0xC0), byte(ptr)), nil
-			}
-
-			// Miss. Add the suffix to the compression table if the
-			// offset can be stored in the available 14 bytes.
-			if len(msg) <= int(^uint16(0)>>2) {
-				compression[string(n.Data[i:])] = len(msg) - compressionOff
-			}
-		}
-	}
-	return append(msg, 0), nil
-}
-
-// unpack unpacks a domain name.
-func (n *Name) unpack(msg []byte, off int) (int, error) {
-	return n.unpackCompressed(msg, off, true /* allowCompression */)
-}
-
-func (n *Name) unpackCompressed(msg []byte, off int, allowCompression bool) (int, error) {
-	// currOff is the current working offset.
-	currOff := off
-
-	// newOff is the offset where the next record will start. Pointers lead
-	// to data that belongs to other names and thus doesn't count towards to
-	// the usage of this name.
-	newOff := off
-
-	// ptr is the number of pointers followed.
-	var ptr int
-
-	// Name is a slice representation of the name data.
-	name := n.Data[:0]
-
-Loop:
-	for {
-		if currOff >= len(msg) {
-			return off, errBaseLen
-		}
-		c := int(msg[currOff])
-		currOff++
-		switch c & 0xC0 {
-		case 0x00: // String segment
-			if c == 0x00 {
-				// A zero length signals the end of the name.
-				break Loop
-			}
-			endOff := currOff + c
-			if endOff > len(msg) {
-				return off, errCalcLen
-			}
-			name = append(name, msg[currOff:endOff]...)
-			name = append(name, '.')
-			currOff = endOff
-		case 0xC0: // Pointer
-			if !allowCompression {
-				return off, errCompressedSRV
-			}
-			if currOff >= len(msg) {
-				return off, errInvalidPtr
-			}
-			c1 := msg[currOff]
-			currOff++
-			if ptr == 0 {
-				newOff = currOff
-			}
-			// Don't follow too many pointers, maybe there's a loop.
-			if ptr++; ptr > 10 {
-				return off, errTooManyPtr
-			}
-			currOff = (c^0xC0)<<8 | int(c1)
-		default:
-			// Prefixes 0x80 and 0x40 are reserved.
-			return off, errReserved
-		}
-	}
-	if len(name) == 0 {
-		name = append(name, '.')
-	}
-	if len(name) > len(n.Data) {
-		return off, errCalcLen
-	}
-	n.Length = uint8(len(name))
-	if ptr == 0 {
-		newOff = currOff
-	}
-	return newOff, nil
-}
-
-func skipName(msg []byte, off int) (int, error) {
-	// newOff is the offset where the next record will start. Pointers lead
-	// to data that belongs to other names and thus doesn't count towards to
-	// the usage of this name.
-	newOff := off
-
-Loop:
-	for {
-		if newOff >= len(msg) {
-			return off, errBaseLen
-		}
-		c := int(msg[newOff])
-		newOff++
-		switch c & 0xC0 {
-		case 0x00:
-			if c == 0x00 {
-				// A zero length signals the end of the name.
-				break Loop
-			}
-			// literal string
-			newOff += c
-			if newOff > len(msg) {
-				return off, errCalcLen
-			}
-		case 0xC0:
-			// Pointer to somewhere else in msg.
-
-			// Pointers are two bytes.
-			newOff++
-
-			// Don't follow the pointer as the data here has ended.
-			break Loop
-		default:
-			// Prefixes 0x80 and 0x40 are reserved.
-			return off, errReserved
-		}
-	}
-
-	return newOff, nil
-}
-
-// A Question is a DNS query.
-type Question struct {
-	Name  Name
-	Type  Type
-	Class Class
-}
-
-// pack appends the wire format of the Question to msg.
-func (q *Question) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
-	msg, err := q.Name.pack(msg, compression, compressionOff)
-	if err != nil {
-		return msg, &nestedError{"Name", err}
-	}
-	msg = packType(msg, q.Type)
-	return packClass(msg, q.Class), nil
-}
-
-// GoString implements fmt.GoStringer.GoString.
-func (q *Question) GoString() string {
-	return "dnsmessage.Question{" +
-		"Name: " + q.Name.GoString() + ", " +
-		"Type: " + q.Type.GoString() + ", " +
-		"Class: " + q.Class.GoString() + "}"
-}
-
-func unpackResourceBody(msg []byte, off int, hdr ResourceHeader) (ResourceBody, int, error) {
-	var (
-		r    ResourceBody
-		err  error
-		name string
-	)
-	switch hdr.Type {
-	case TypeA:
-		var rb AResource
-		rb, err = unpackAResource(msg, off)
-		r = &rb
-		name = "A"
-	case TypeNS:
-		var rb NSResource
-		rb, err = unpackNSResource(msg, off)
-		r = &rb
-		name = "NS"
-	case TypeCNAME:
-		var rb CNAMEResource
-		rb, err = unpackCNAMEResource(msg, off)
-		r = &rb
-		name = "CNAME"
-	case TypeSOA:
-		var rb SOAResource
-		rb, err = unpackSOAResource(msg, off)
-		r = &rb
-		name = "SOA"
-	case TypePTR:
-		var rb PTRResource
-		rb, err = unpackPTRResource(msg, off)
-		r = &rb
-		name = "PTR"
-	case TypeMX:
-		var rb MXResource
-		rb, err = unpackMXResource(msg, off)
-		r = &rb
-		name = "MX"
-	case TypeTXT:
-		var rb TXTResource
-		rb, err = unpackTXTResource(msg, off, hdr.Length)
-		r = &rb
-		name = "TXT"
-	case TypeAAAA:
-		var rb AAAAResource
-		rb, err = unpackAAAAResource(msg, off)
-		r = &rb
-		name = "AAAA"
-	case TypeSRV:
-		var rb SRVResource
-		rb, err = unpackSRVResource(msg, off)
-		r = &rb
-		name = "SRV"
-	case TypeOPT:
-		var rb OPTResource
-		rb, err = unpackOPTResource(msg, off, hdr.Length)
-		r = &rb
-		name = "OPT"
-	default:
-		var rb UnknownResource
-		rb, err = unpackUnknownResource(hdr.Type, msg, off, hdr.Length)
-		r = &rb
-		name = "Unknown"
-	}
-	if err != nil {
-		return nil, off, &nestedError{name + " record", err}
-	}
-	return r, off + int(hdr.Length), nil
-}
-
-// A CNAMEResource is a CNAME Resource record.
-type CNAMEResource struct {
-	CNAME Name
-}
-
-func (r *CNAMEResource) realType() Type {
-	return TypeCNAME
-}
-
-// pack appends the wire format of the CNAMEResource to msg.
-func (r *CNAMEResource) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
-	return r.CNAME.pack(msg, compression, compressionOff)
-}
-
-// GoString implements fmt.GoStringer.GoString.
-func (r *CNAMEResource) GoString() string {
-	return "dnsmessage.CNAMEResource{CNAME: " + r.CNAME.GoString() + "}"
-}
-
-func unpackCNAMEResource(msg []byte, off int) (CNAMEResource, error) {
-	var cname Name
-	if _, err := cname.unpack(msg, off); err != nil {
-		return CNAMEResource{}, err
-	}
-	return CNAMEResource{cname}, nil
-}
-
-// An MXResource is an MX Resource record.
-type MXResource struct {
-	Pref uint16
-	MX   Name
-}
-
-func (r *MXResource) realType() Type {
-	return TypeMX
-}
-
-// pack appends the wire format of the MXResource to msg.
-func (r *MXResource) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
-	oldMsg := msg
-	msg = packUint16(msg, r.Pref)
-	msg, err := r.MX.pack(msg, compression, compressionOff)
-	if err != nil {
-		return oldMsg, &nestedError{"MXResource.MX", err}
-	}
-	return msg, nil
-}
-
-// GoString implements fmt.GoStringer.GoString.
-func (r *MXResource) GoString() string {
-	return "dnsmessage.MXResource{" +
-		"Pref: " + printUint16(r.Pref) + ", " +
-		"MX: " + r.MX.GoString() + "}"
-}
-
-func unpackMXResource(msg []byte, off int) (MXResource, error) {
-	pref, off, err := unpackUint16(msg, off)
-	if err != nil {
-		return MXResource{}, &nestedError{"Pref", err}
-	}
-	var mx Name
-	if _, err := mx.unpack(msg, off); err != nil {
-		return MXResource{}, &nestedError{"MX", err}
-	}
-	return MXResource{pref, mx}, nil
-}
-
-// An NSResource is an NS Resource record.
-type NSResource struct {
-	NS Name
-}
-
-func (r *NSResource) realType() Type {
-	return TypeNS
-}
-
-// pack appends the wire format of the NSResource to msg.
-func (r *NSResource) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
-	return r.NS.pack(msg, compression, compressionOff)
-}
-
-// GoString implements fmt.GoStringer.GoString.
-func (r *NSResource) GoString() string {
-	return "dnsmessage.NSResource{NS: " + r.NS.GoString() + "}"
-}
-
-func unpackNSResource(msg []byte, off int) (NSResource, error) {
-	var ns Name
-	if _, err := ns.unpack(msg, off); err != nil {
-		return NSResource{}, err
-	}
-	return NSResource{ns}, nil
-}
-
-// A PTRResource is a PTR Resource record.
-type PTRResource struct {
-	PTR Name
-}
-
-func (r *PTRResource) realType() Type {
-	return TypePTR
-}
-
-// pack appends the wire format of the PTRResource to msg.
-func (r *PTRResource) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
-	return r.PTR.pack(msg, compression, compressionOff)
-}
-
-// GoString implements fmt.GoStringer.GoString.
-func (r *PTRResource) GoString() string {
-	return "dnsmessage.PTRResource{PTR: " + r.PTR.GoString() + "}"
-}
-
-func unpackPTRResource(msg []byte, off int) (PTRResource, error) {
-	var ptr Name
-	if _, err := ptr.unpack(msg, off); err != nil {
-		return PTRResource{}, err
-	}
-	return PTRResource{ptr}, nil
-}
-
-// An SOAResource is an SOA Resource record.
-type SOAResource struct {
-	NS      Name
-	MBox    Name
-	Serial  uint32
-	Refresh uint32
-	Retry   uint32
-	Expire  uint32
-
-	// MinTTL the is the default TTL of Resources records which did not
-	// contain a TTL value and the TTL of negative responses. (RFC 2308
-	// Section 4)
-	MinTTL uint32
-}
-
-func (r *SOAResource) realType() Type {
-	return TypeSOA
-}
-
-// pack appends the wire format of the SOAResource to msg.
-func (r *SOAResource) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
-	oldMsg := msg
-	msg, err := r.NS.pack(msg, compression, compressionOff)
-	if err != nil {
-		return oldMsg, &nestedError{"SOAResource.NS", err}
-	}
-	msg, err = r.MBox.pack(msg, compression, compressionOff)
-	if err != nil {
-		return oldMsg, &nestedError{"SOAResource.MBox", err}
-	}
-	msg = packUint32(msg, r.Serial)
-	msg = packUint32(msg, r.Refresh)
-	msg = packUint32(msg, r.Retry)
-	msg = packUint32(msg, r.Expire)
-	return packUint32(msg, r.MinTTL), nil
-}
-
-// GoString implements fmt.GoStringer.GoString.
-func (r *SOAResource) GoString() string {
-	return "dnsmessage.SOAResource{" +
-		"NS: " + r.NS.GoString() + ", " +
-		"MBox: " + r.MBox.GoString() + ", " +
-		"Serial: " + printUint32(r.Serial) + ", " +
-		"Refresh: " + printUint32(r.Refresh) + ", " +
-		"Retry: " + printUint32(r.Retry) + ", " +
-		"Expire: " + printUint32(r.Expire) + ", " +
-		"MinTTL: " + printUint32(r.MinTTL) + "}"
-}
-
-func unpackSOAResource(msg []byte, off int) (SOAResource, error) {
-	var ns Name
-	off, err := ns.unpack(msg, off)
-	if err != nil {
-		return SOAResource{}, &nestedError{"NS", err}
-	}
-	var mbox Name
-	if off, err = mbox.unpack(msg, off); err != nil {
-		return SOAResource{}, &nestedError{"MBox", err}
-	}
-	serial, off, err := unpackUint32(msg, off)
-	if err != nil {
-		return SOAResource{}, &nestedError{"Serial", err}
-	}
-	refresh, off, err := unpackUint32(msg, off)
-	if err != nil {
-		return SOAResource{}, &nestedError{"Refresh", err}
-	}
-	retry, off, err := unpackUint32(msg, off)
-	if err != nil {
-		return SOAResource{}, &nestedError{"Retry", err}
-	}
-	expire, off, err := unpackUint32(msg, off)
-	if err != nil {
-		return SOAResource{}, &nestedError{"Expire", err}
-	}
-	minTTL, _, err := unpackUint32(msg, off)
-	if err != nil {
-		return SOAResource{}, &nestedError{"MinTTL", err}
-	}
-	return SOAResource{ns, mbox, serial, refresh, retry, expire, minTTL}, nil
-}
-
-// A TXTResource is a TXT Resource record.
-type TXTResource struct {
-	TXT []string
-}
-
-func (r *TXTResource) realType() Type {
-	return TypeTXT
-}
-
-// pack appends the wire format of the TXTResource to msg.
-func (r *TXTResource) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
-	oldMsg := msg
-	for _, s := range r.TXT {
-		var err error
-		msg, err = packText(msg, s)
-		if err != nil {
-			return oldMsg, err
-		}
-	}
-	return msg, nil
-}
-
-// GoString implements fmt.GoStringer.GoString.
-func (r *TXTResource) GoString() string {
-	s := "dnsmessage.TXTResource{TXT: []string{"
-	if len(r.TXT) == 0 {
-		return s + "}}"
-	}
-	s += `"` + printString([]byte(r.TXT[0]))
-	for _, t := range r.TXT[1:] {
-		s += `", "` + printString([]byte(t))
-	}
-	return s + `"}}`
-}
-
-func unpackTXTResource(msg []byte, off int, length uint16) (TXTResource, error) {
-	txts := make([]string, 0, 1)
-	for n := uint16(0); n < length; {
-		var t string
-		var err error
-		if t, off, err = unpackText(msg, off); err != nil {
-			return TXTResource{}, &nestedError{"text", err}
-		}
-		// Check if we got too many bytes.
-		if length-n < uint16(len(t))+1 {
-			return TXTResource{}, errCalcLen
-		}
-		n += uint16(len(t)) + 1
-		txts = append(txts, t)
-	}
-	return TXTResource{txts}, nil
-}
-
-// An SRVResource is an SRV Resource record.
-type SRVResource struct {
-	Priority uint16
-	Weight   uint16
-	Port     uint16
-	Target   Name // Not compressed as per RFC 2782.
-}
-
-func (r *SRVResource) realType() Type {
-	return TypeSRV
-}
-
-// pack appends the wire format of the SRVResource to msg.
-func (r *SRVResource) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
-	oldMsg := msg
-	msg = packUint16(msg, r.Priority)
-	msg = packUint16(msg, r.Weight)
-	msg = packUint16(msg, r.Port)
-	msg, err := r.Target.pack(msg, nil, compressionOff)
-	if err != nil {
-		return oldMsg, &nestedError{"SRVResource.Target", err}
-	}
-	return msg, nil
-}
-
-// GoString implements fmt.GoStringer.GoString.
-func (r *SRVResource) GoString() string {
-	return "dnsmessage.SRVResource{" +
-		"Priority: " + printUint16(r.Priority) + ", " +
-		"Weight: " + printUint16(r.Weight) + ", " +
-		"Port: " + printUint16(r.Port) + ", " +
-		"Target: " + r.Target.GoString() + "}"
-}
-
-func unpackSRVResource(msg []byte, off int) (SRVResource, error) {
-	priority, off, err := unpackUint16(msg, off)
-	if err != nil {
-		return SRVResource{}, &nestedError{"Priority", err}
-	}
-	weight, off, err := unpackUint16(msg, off)
-	if err != nil {
-		return SRVResource{}, &nestedError{"Weight", err}
-	}
-	port, off, err := unpackUint16(msg, off)
-	if err != nil {
-		return SRVResource{}, &nestedError{"Port", err}
-	}
-	var target Name
-	if _, err := target.unpackCompressed(msg, off, false /* allowCompression */); err != nil {
-		return SRVResource{}, &nestedError{"Target", err}
-	}
-	return SRVResource{priority, weight, port, target}, nil
-}
-
-// An AResource is an A Resource record.
-type AResource struct {
-	A [4]byte
-}
-
-func (r *AResource) realType() Type {
-	return TypeA
-}
-
-// pack appends the wire format of the AResource to msg.
-func (r *AResource) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
-	return packBytes(msg, r.A[:]), nil
-}
-
-// GoString implements fmt.GoStringer.GoString.
-func (r *AResource) GoString() string {
-	return "dnsmessage.AResource{" +
-		"A: [4]byte{" + printByteSlice(r.A[:]) + "}}"
-}
-
-func unpackAResource(msg []byte, off int) (AResource, error) {
-	var a [4]byte
-	if _, err := unpackBytes(msg, off, a[:]); err != nil {
-		return AResource{}, err
-	}
-	return AResource{a}, nil
-}
-
-// An AAAAResource is an AAAA Resource record.
-type AAAAResource struct {
-	AAAA [16]byte
-}
-
-func (r *AAAAResource) realType() Type {
-	return TypeAAAA
-}
-
-// GoString implements fmt.GoStringer.GoString.
-func (r *AAAAResource) GoString() string {
-	return "dnsmessage.AAAAResource{" +
-		"AAAA: [16]byte{" + printByteSlice(r.AAAA[:]) + "}}"
-}
-
-// pack appends the wire format of the AAAAResource to msg.
-func (r *AAAAResource) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
-	return packBytes(msg, r.AAAA[:]), nil
-}
-
-func unpackAAAAResource(msg []byte, off int) (AAAAResource, error) {
-	var aaaa [16]byte
-	if _, err := unpackBytes(msg, off, aaaa[:]); err != nil {
-		return AAAAResource{}, err
-	}
-	return AAAAResource{aaaa}, nil
-}
-
-// An OPTResource is an OPT pseudo Resource record.
-//
-// The pseudo resource record is part of the extension mechanisms for DNS
-// as defined in RFC 6891.
-type OPTResource struct {
-	Options []Option
-}
-
-// An Option represents a DNS message option within OPTResource.
-//
-// The message option is part of the extension mechanisms for DNS as
-// defined in RFC 6891.
-type Option struct {
-	Code uint16 // option code
-	Data []byte
-}
-
-// GoString implements fmt.GoStringer.GoString.
-func (o *Option) GoString() string {
-	return "dnsmessage.Option{" +
-		"Code: " + printUint16(o.Code) + ", " +
-		"Data: []byte{" + printByteSlice(o.Data) + "}}"
-}
-
-func (r *OPTResource) realType() Type {
-	return TypeOPT
-}
-
-func (r *OPTResource) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
-	for _, opt := range r.Options {
-		msg = packUint16(msg, opt.Code)
-		l := uint16(len(opt.Data))
-		msg = packUint16(msg, l)
-		msg = packBytes(msg, opt.Data)
-	}
-	return msg, nil
-}
-
-// GoString implements fmt.GoStringer.GoString.
-func (r *OPTResource) GoString() string {
-	s := "dnsmessage.OPTResource{Options: []dnsmessage.Option{"
-	if len(r.Options) == 0 {
-		return s + "}}"
-	}
-	s += r.Options[0].GoString()
-	for _, o := range r.Options[1:] {
-		s += ", " + o.GoString()
-	}
-	return s + "}}"
-}
-
-func unpackOPTResource(msg []byte, off int, length uint16) (OPTResource, error) {
-	var opts []Option
-	for oldOff := off; off < oldOff+int(length); {
-		var err error
-		var o Option
-		o.Code, off, err = unpackUint16(msg, off)
-		if err != nil {
-			return OPTResource{}, &nestedError{"Code", err}
-		}
-		var l uint16
-		l, off, err = unpackUint16(msg, off)
-		if err != nil {
-			return OPTResource{}, &nestedError{"Data", err}
-		}
-		o.Data = make([]byte, l)
-		if copy(o.Data, msg[off:]) != int(l) {
-			return OPTResource{}, &nestedError{"Data", errCalcLen}
-		}
-		off += int(l)
-		opts = append(opts, o)
-	}
-	return OPTResource{opts}, nil
-}
-
-// An UnknownResource is a catch-all container for unknown record types.
-type UnknownResource struct {
-	Type Type
-	Data []byte
-}
-
-func (r *UnknownResource) realType() Type {
-	return r.Type
-}
-
-// pack appends the wire format of the UnknownResource to msg.
-func (r *UnknownResource) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
-	return packBytes(msg, r.Data[:]), nil
-}
-
-// GoString implements fmt.GoStringer.GoString.
-func (r *UnknownResource) GoString() string {
-	return "dnsmessage.UnknownResource{" +
-		"Type: " + r.Type.GoString() + ", " +
-		"Data: []byte{" + printByteSlice(r.Data) + "}}"
-}
-
-func unpackUnknownResource(recordType Type, msg []byte, off int, length uint16) (UnknownResource, error) {
-	parsed := UnknownResource{
-		Type: recordType,
-		Data: make([]byte, length),
-	}
-	if _, err := unpackBytes(msg, off, parsed.Data); err != nil {
-		return UnknownResource{}, err
-	}
-	return parsed, nil
-}
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/http/httpguts/httplex.go b/contrib/go/_std_1.18/src/vendor/golang.org/x/net/http/httpguts/httplex.go
deleted file mode 100644
index c79aa73f28..0000000000
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/http/httpguts/httplex.go
+++ /dev/null
@@ -1,348 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package httpguts
-
-import (
-	"net"
-	"strings"
-	"unicode/utf8"
-
-	"golang.org/x/net/idna"
-)
-
-var isTokenTable = [127]bool{
-	'!':  true,
-	'#':  true,
-	'$':  true,
-	'%':  true,
-	'&':  true,
-	'\'': true,
-	'*':  true,
-	'+':  true,
-	'-':  true,
-	'.':  true,
-	'0':  true,
-	'1':  true,
-	'2':  true,
-	'3':  true,
-	'4':  true,
-	'5':  true,
-	'6':  true,
-	'7':  true,
-	'8':  true,
-	'9':  true,
-	'A':  true,
-	'B':  true,
-	'C':  true,
-	'D':  true,
-	'E':  true,
-	'F':  true,
-	'G':  true,
-	'H':  true,
-	'I':  true,
-	'J':  true,
-	'K':  true,
-	'L':  true,
-	'M':  true,
-	'N':  true,
-	'O':  true,
-	'P':  true,
-	'Q':  true,
-	'R':  true,
-	'S':  true,
-	'T':  true,
-	'U':  true,
-	'W':  true,
-	'V':  true,
-	'X':  true,
-	'Y':  true,
-	'Z':  true,
-	'^':  true,
-	'_':  true,
-	'`':  true,
-	'a':  true,
-	'b':  true,
-	'c':  true,
-	'd':  true,
-	'e':  true,
-	'f':  true,
-	'g':  true,
-	'h':  true,
-	'i':  true,
-	'j':  true,
-	'k':  true,
-	'l':  true,
-	'm':  true,
-	'n':  true,
-	'o':  true,
-	'p':  true,
-	'q':  true,
-	'r':  true,
-	's':  true,
-	't':  true,
-	'u':  true,
-	'v':  true,
-	'w':  true,
-	'x':  true,
-	'y':  true,
-	'z':  true,
-	'|':  true,
-	'~':  true,
-}
-
-func IsTokenRune(r rune) bool {
-	i := int(r)
-	return i < len(isTokenTable) && isTokenTable[i]
-}
-
-func isNotToken(r rune) bool {
-	return !IsTokenRune(r)
-}
-
-// HeaderValuesContainsToken reports whether any string in values
-// contains the provided token, ASCII case-insensitively.
-func HeaderValuesContainsToken(values []string, token string) bool {
-	for _, v := range values {
-		if headerValueContainsToken(v, token) {
-			return true
-		}
-	}
-	return false
-}
-
-// isOWS reports whether b is an optional whitespace byte, as defined
-// by RFC 7230 section 3.2.3.
-func isOWS(b byte) bool { return b == ' ' || b == '\t' }
-
-// trimOWS returns x with all optional whitespace removes from the
-// beginning and end.
-func trimOWS(x string) string {
-	// TODO: consider using strings.Trim(x, " \t") instead,
-	// if and when it's fast enough. See issue 10292.
-	// But this ASCII-only code will probably always beat UTF-8
-	// aware code.
-	for len(x) > 0 && isOWS(x[0]) {
-		x = x[1:]
-	}
-	for len(x) > 0 && isOWS(x[len(x)-1]) {
-		x = x[:len(x)-1]
-	}
-	return x
-}
-
-// headerValueContainsToken reports whether v (assumed to be a
-// 0#element, in the ABNF extension described in RFC 7230 section 7)
-// contains token amongst its comma-separated tokens, ASCII
-// case-insensitively.
-func headerValueContainsToken(v string, token string) bool {
-	for comma := strings.IndexByte(v, ','); comma != -1; comma = strings.IndexByte(v, ',') {
-		if tokenEqual(trimOWS(v[:comma]), token) {
-			return true
-		}
-		v = v[comma+1:]
-	}
-	return tokenEqual(trimOWS(v), token)
-}
-
-// lowerASCII returns the ASCII lowercase version of b.
-func lowerASCII(b byte) byte {
-	if 'A' <= b && b <= 'Z' {
-		return b + ('a' - 'A')
-	}
-	return b
-}
-
-// tokenEqual reports whether t1 and t2 are equal, ASCII case-insensitively.
-func tokenEqual(t1, t2 string) bool {
-	if len(t1) != len(t2) {
-		return false
-	}
-	for i, b := range t1 {
-		if b >= utf8.RuneSelf {
-			// No UTF-8 or non-ASCII allowed in tokens.
-			return false
-		}
-		if lowerASCII(byte(b)) != lowerASCII(t2[i]) {
-			return false
-		}
-	}
-	return true
-}
-
-// isLWS reports whether b is linear white space, according
-// to http://www.w3.org/Protocols/rfc2616/rfc2616-sec2.html#sec2.2
-//      LWS            = [CRLF] 1*( SP | HT )
-func isLWS(b byte) bool { return b == ' ' || b == '\t' }
-
-// isCTL reports whether b is a control byte, according
-// to http://www.w3.org/Protocols/rfc2616/rfc2616-sec2.html#sec2.2
-//      CTL            = <any US-ASCII control character
-//                       (octets 0 - 31) and DEL (127)>
-func isCTL(b byte) bool {
-	const del = 0x7f // a CTL
-	return b < ' ' || b == del
-}
-
-// ValidHeaderFieldName reports whether v is a valid HTTP/1.x header name.
-// HTTP/2 imposes the additional restriction that uppercase ASCII
-// letters are not allowed.
-//
-//  RFC 7230 says:
-//   header-field   = field-name ":" OWS field-value OWS
-//   field-name     = token
-//   token          = 1*tchar
-//   tchar = "!" / "#" / "$" / "%" / "&" / "'" / "*" / "+" / "-" / "." /
-//           "^" / "_" / "`" / "|" / "~" / DIGIT / ALPHA
-func ValidHeaderFieldName(v string) bool {
-	if len(v) == 0 {
-		return false
-	}
-	for _, r := range v {
-		if !IsTokenRune(r) {
-			return false
-		}
-	}
-	return true
-}
-
-// ValidHostHeader reports whether h is a valid host header.
-func ValidHostHeader(h string) bool {
-	// The latest spec is actually this:
-	//
-	// http://tools.ietf.org/html/rfc7230#section-5.4
-	//     Host = uri-host [ ":" port ]
-	//
-	// Where uri-host is:
-	//     http://tools.ietf.org/html/rfc3986#section-3.2.2
-	//
-	// But we're going to be much more lenient for now and just
-	// search for any byte that's not a valid byte in any of those
-	// expressions.
-	for i := 0; i < len(h); i++ {
-		if !validHostByte[h[i]] {
-			return false
-		}
-	}
-	return true
-}
-
-// See the validHostHeader comment.
-var validHostByte = [256]bool{
-	'0': true, '1': true, '2': true, '3': true, '4': true, '5': true, '6': true, '7': true,
-	'8': true, '9': true,
-
-	'a': true, 'b': true, 'c': true, 'd': true, 'e': true, 'f': true, 'g': true, 'h': true,
-	'i': true, 'j': true, 'k': true, 'l': true, 'm': true, 'n': true, 'o': true, 'p': true,
-	'q': true, 'r': true, 's': true, 't': true, 'u': true, 'v': true, 'w': true, 'x': true,
-	'y': true, 'z': true,
-
-	'A': true, 'B': true, 'C': true, 'D': true, 'E': true, 'F': true, 'G': true, 'H': true,
-	'I': true, 'J': true, 'K': true, 'L': true, 'M': true, 'N': true, 'O': true, 'P': true,
-	'Q': true, 'R': true, 'S': true, 'T': true, 'U': true, 'V': true, 'W': true, 'X': true,
-	'Y': true, 'Z': true,
-
-	'!':  true, // sub-delims
-	'$':  true, // sub-delims
-	'%':  true, // pct-encoded (and used in IPv6 zones)
-	'&':  true, // sub-delims
-	'(':  true, // sub-delims
-	')':  true, // sub-delims
-	'*':  true, // sub-delims
-	'+':  true, // sub-delims
-	',':  true, // sub-delims
-	'-':  true, // unreserved
-	'.':  true, // unreserved
-	':':  true, // IPv6address + Host expression's optional port
-	';':  true, // sub-delims
-	'=':  true, // sub-delims
-	'[':  true,
-	'\'': true, // sub-delims
-	']':  true,
-	'_':  true, // unreserved
-	'~':  true, // unreserved
-}
-
-// ValidHeaderFieldValue reports whether v is a valid "field-value" according to
-// http://www.w3.org/Protocols/rfc2616/rfc2616-sec4.html#sec4.2 :
-//
-//        message-header = field-name ":" [ field-value ]
-//        field-value    = *( field-content | LWS )
-//        field-content  = <the OCTETs making up the field-value
-//                         and consisting of either *TEXT or combinations
-//                         of token, separators, and quoted-string>
-//
-// http://www.w3.org/Protocols/rfc2616/rfc2616-sec2.html#sec2.2 :
-//
-//        TEXT           = <any OCTET except CTLs,
-//                          but including LWS>
-//        LWS            = [CRLF] 1*( SP | HT )
-//        CTL            = <any US-ASCII control character
-//                         (octets 0 - 31) and DEL (127)>
-//
-// RFC 7230 says:
-//  field-value    = *( field-content / obs-fold )
-//  obj-fold       =  N/A to http2, and deprecated
-//  field-content  = field-vchar [ 1*( SP / HTAB ) field-vchar ]
-//  field-vchar    = VCHAR / obs-text
-//  obs-text       = %x80-FF
-//  VCHAR          = "any visible [USASCII] character"
-//
-// http2 further says: "Similarly, HTTP/2 allows header field values
-// that are not valid. While most of the values that can be encoded
-// will not alter header field parsing, carriage return (CR, ASCII
-// 0xd), line feed (LF, ASCII 0xa), and the zero character (NUL, ASCII
-// 0x0) might be exploited by an attacker if they are translated
-// verbatim. Any request or response that contains a character not
-// permitted in a header field value MUST be treated as malformed
-// (Section 8.1.2.6). Valid characters are defined by the
-// field-content ABNF rule in Section 3.2 of [RFC7230]."
-//
-// This function does not (yet?) properly handle the rejection of
-// strings that begin or end with SP or HTAB.
-func ValidHeaderFieldValue(v string) bool {
-	for i := 0; i < len(v); i++ {
-		b := v[i]
-		if isCTL(b) && !isLWS(b) {
-			return false
-		}
-	}
-	return true
-}
-
-func isASCII(s string) bool {
-	for i := 0; i < len(s); i++ {
-		if s[i] >= utf8.RuneSelf {
-			return false
-		}
-	}
-	return true
-}
-
-// PunycodeHostPort returns the IDNA Punycode version
-// of the provided "host" or "host:port" string.
-func PunycodeHostPort(v string) (string, error) {
-	if isASCII(v) {
-		return v, nil
-	}
-
-	host, port, err := net.SplitHostPort(v)
-	if err != nil {
-		// The input 'v' argument was just a "host" argument,
-		// without a port. This error should not be returned
-		// to the caller.
-		host = v
-		port = ""
-	}
-	host, err = idna.ToASCII(host)
-	if err != nil {
-		// Non-UTF-8? Not representable in Punycode, in any
-		// case.
-		return "", err
-	}
-	if port == "" {
-		return host, nil
-	}
-	return net.JoinHostPort(host, port), nil
-}
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/http/httpproxy/proxy.go b/contrib/go/_std_1.18/src/vendor/golang.org/x/net/http/httpproxy/proxy.go
deleted file mode 100644
index d2c8c87eab..0000000000
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/http/httpproxy/proxy.go
+++ /dev/null
@@ -1,368 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package httpproxy provides support for HTTP proxy determination
-// based on environment variables, as provided by net/http's
-// ProxyFromEnvironment function.
-//
-// The API is not subject to the Go 1 compatibility promise and may change at
-// any time.
-package httpproxy
-
-import (
-	"errors"
-	"fmt"
-	"net"
-	"net/url"
-	"os"
-	"strings"
-	"unicode/utf8"
-
-	"golang.org/x/net/idna"
-)
-
-// Config holds configuration for HTTP proxy settings. See
-// FromEnvironment for details.
-type Config struct {
-	// HTTPProxy represents the value of the HTTP_PROXY or
-	// http_proxy environment variable. It will be used as the proxy
-	// URL for HTTP requests unless overridden by NoProxy.
-	HTTPProxy string
-
-	// HTTPSProxy represents the HTTPS_PROXY or https_proxy
-	// environment variable. It will be used as the proxy URL for
-	// HTTPS requests unless overridden by NoProxy.
-	HTTPSProxy string
-
-	// NoProxy represents the NO_PROXY or no_proxy environment
-	// variable. It specifies a string that contains comma-separated values
-	// specifying hosts that should be excluded from proxying. Each value is
-	// represented by an IP address prefix (1.2.3.4), an IP address prefix in
-	// CIDR notation (1.2.3.4/8), a domain name, or a special DNS label (*).
-	// An IP address prefix and domain name can also include a literal port
-	// number (1.2.3.4:80).
-	// A domain name matches that name and all subdomains. A domain name with
-	// a leading "." matches subdomains only. For example "foo.com" matches
-	// "foo.com" and "bar.foo.com"; ".y.com" matches "x.y.com" but not "y.com".
-	// A single asterisk (*) indicates that no proxying should be done.
-	// A best effort is made to parse the string and errors are
-	// ignored.
-	NoProxy string
-
-	// CGI holds whether the current process is running
-	// as a CGI handler (FromEnvironment infers this from the
-	// presence of a REQUEST_METHOD environment variable).
-	// When this is set, ProxyForURL will return an error
-	// when HTTPProxy applies, because a client could be
-	// setting HTTP_PROXY maliciously. See https://golang.org/s/cgihttpproxy.
-	CGI bool
-}
-
-// config holds the parsed configuration for HTTP proxy settings.
-type config struct {
-	// Config represents the original configuration as defined above.
-	Config
-
-	// httpsProxy is the parsed URL of the HTTPSProxy if defined.
-	httpsProxy *url.URL
-
-	// httpProxy is the parsed URL of the HTTPProxy if defined.
-	httpProxy *url.URL
-
-	// ipMatchers represent all values in the NoProxy that are IP address
-	// prefixes or an IP address in CIDR notation.
-	ipMatchers []matcher
-
-	// domainMatchers represent all values in the NoProxy that are a domain
-	// name or hostname & domain name
-	domainMatchers []matcher
-}
-
-// FromEnvironment returns a Config instance populated from the
-// environment variables HTTP_PROXY, HTTPS_PROXY and NO_PROXY (or the
-// lowercase versions thereof). HTTPS_PROXY takes precedence over
-// HTTP_PROXY for https requests.
-//
-// The environment values may be either a complete URL or a
-// "host[:port]", in which case the "http" scheme is assumed. An error
-// is returned if the value is a different form.
-func FromEnvironment() *Config {
-	return &Config{
-		HTTPProxy:  getEnvAny("HTTP_PROXY", "http_proxy"),
-		HTTPSProxy: getEnvAny("HTTPS_PROXY", "https_proxy"),
-		NoProxy:    getEnvAny("NO_PROXY", "no_proxy"),
-		CGI:        os.Getenv("REQUEST_METHOD") != "",
-	}
-}
-
-func getEnvAny(names ...string) string {
-	for _, n := range names {
-		if val := os.Getenv(n); val != "" {
-			return val
-		}
-	}
-	return ""
-}
-
-// ProxyFunc returns a function that determines the proxy URL to use for
-// a given request URL. Changing the contents of cfg will not affect
-// proxy functions created earlier.
-//
-// A nil URL and nil error are returned if no proxy is defined in the
-// environment, or a proxy should not be used for the given request, as
-// defined by NO_PROXY.
-//
-// As a special case, if req.URL.Host is "localhost" or a loopback address
-// (with or without a port number), then a nil URL and nil error will be returned.
-func (cfg *Config) ProxyFunc() func(reqURL *url.URL) (*url.URL, error) {
-	// Preprocess the Config settings for more efficient evaluation.
-	cfg1 := &config{
-		Config: *cfg,
-	}
-	cfg1.init()
-	return cfg1.proxyForURL
-}
-
-func (cfg *config) proxyForURL(reqURL *url.URL) (*url.URL, error) {
-	var proxy *url.URL
-	if reqURL.Scheme == "https" {
-		proxy = cfg.httpsProxy
-	} else if reqURL.Scheme == "http" {
-		proxy = cfg.httpProxy
-		if proxy != nil && cfg.CGI {
-			return nil, errors.New("refusing to use HTTP_PROXY value in CGI environment; see golang.org/s/cgihttpproxy")
-		}
-	}
-	if proxy == nil {
-		return nil, nil
-	}
-	if !cfg.useProxy(canonicalAddr(reqURL)) {
-		return nil, nil
-	}
-
-	return proxy, nil
-}
-
-func parseProxy(proxy string) (*url.URL, error) {
-	if proxy == "" {
-		return nil, nil
-	}
-
-	proxyURL, err := url.Parse(proxy)
-	if err != nil ||
-		(proxyURL.Scheme != "http" &&
-			proxyURL.Scheme != "https" &&
-			proxyURL.Scheme != "socks5") {
-		// proxy was bogus. Try prepending "http://" to it and
-		// see if that parses correctly. If not, we fall
-		// through and complain about the original one.
-		if proxyURL, err := url.Parse("http://" + proxy); err == nil {
-			return proxyURL, nil
-		}
-	}
-	if err != nil {
-		return nil, fmt.Errorf("invalid proxy address %q: %v", proxy, err)
-	}
-	return proxyURL, nil
-}
-
-// useProxy reports whether requests to addr should use a proxy,
-// according to the NO_PROXY or no_proxy environment variable.
-// addr is always a canonicalAddr with a host and port.
-func (cfg *config) useProxy(addr string) bool {
-	if len(addr) == 0 {
-		return true
-	}
-	host, port, err := net.SplitHostPort(addr)
-	if err != nil {
-		return false
-	}
-	if host == "localhost" {
-		return false
-	}
-	ip := net.ParseIP(host)
-	if ip != nil {
-		if ip.IsLoopback() {
-			return false
-		}
-	}
-
-	addr = strings.ToLower(strings.TrimSpace(host))
-
-	if ip != nil {
-		for _, m := range cfg.ipMatchers {
-			if m.match(addr, port, ip) {
-				return false
-			}
-		}
-	}
-	for _, m := range cfg.domainMatchers {
-		if m.match(addr, port, ip) {
-			return false
-		}
-	}
-	return true
-}
-
-func (c *config) init() {
-	if parsed, err := parseProxy(c.HTTPProxy); err == nil {
-		c.httpProxy = parsed
-	}
-	if parsed, err := parseProxy(c.HTTPSProxy); err == nil {
-		c.httpsProxy = parsed
-	}
-
-	for _, p := range strings.Split(c.NoProxy, ",") {
-		p = strings.ToLower(strings.TrimSpace(p))
-		if len(p) == 0 {
-			continue
-		}
-
-		if p == "*" {
-			c.ipMatchers = []matcher{allMatch{}}
-			c.domainMatchers = []matcher{allMatch{}}
-			return
-		}
-
-		// IPv4/CIDR, IPv6/CIDR
-		if _, pnet, err := net.ParseCIDR(p); err == nil {
-			c.ipMatchers = append(c.ipMatchers, cidrMatch{cidr: pnet})
-			continue
-		}
-
-		// IPv4:port, [IPv6]:port
-		phost, pport, err := net.SplitHostPort(p)
-		if err == nil {
-			if len(phost) == 0 {
-				// There is no host part, likely the entry is malformed; ignore.
-				continue
-			}
-			if phost[0] == '[' && phost[len(phost)-1] == ']' {
-				phost = phost[1 : len(phost)-1]
-			}
-		} else {
-			phost = p
-		}
-		// IPv4, IPv6
-		if pip := net.ParseIP(phost); pip != nil {
-			c.ipMatchers = append(c.ipMatchers, ipMatch{ip: pip, port: pport})
-			continue
-		}
-
-		if len(phost) == 0 {
-			// There is no host part, likely the entry is malformed; ignore.
-			continue
-		}
-
-		// domain.com or domain.com:80
-		// foo.com matches bar.foo.com
-		// .domain.com or .domain.com:port
-		// *.domain.com or *.domain.com:port
-		if strings.HasPrefix(phost, "*.") {
-			phost = phost[1:]
-		}
-		matchHost := false
-		if phost[0] != '.' {
-			matchHost = true
-			phost = "." + phost
-		}
-		c.domainMatchers = append(c.domainMatchers, domainMatch{host: phost, port: pport, matchHost: matchHost})
-	}
-}
-
-var portMap = map[string]string{
-	"http":   "80",
-	"https":  "443",
-	"socks5": "1080",
-}
-
-// canonicalAddr returns url.Host but always with a ":port" suffix
-func canonicalAddr(url *url.URL) string {
-	addr := url.Hostname()
-	if v, err := idnaASCII(addr); err == nil {
-		addr = v
-	}
-	port := url.Port()
-	if port == "" {
-		port = portMap[url.Scheme]
-	}
-	return net.JoinHostPort(addr, port)
-}
-
-// Given a string of the form "host", "host:port", or "[ipv6::address]:port",
-// return true if the string includes a port.
-func hasPort(s string) bool { return strings.LastIndex(s, ":") > strings.LastIndex(s, "]") }
-
-func idnaASCII(v string) (string, error) {
-	// TODO: Consider removing this check after verifying performance is okay.
-	// Right now punycode verification, length checks, context checks, and the
-	// permissible character tests are all omitted. It also prevents the ToASCII
-	// call from salvaging an invalid IDN, when possible. As a result it may be
-	// possible to have two IDNs that appear identical to the user where the
-	// ASCII-only version causes an error downstream whereas the non-ASCII
-	// version does not.
-	// Note that for correct ASCII IDNs ToASCII will only do considerably more
-	// work, but it will not cause an allocation.
-	if isASCII(v) {
-		return v, nil
-	}
-	return idna.Lookup.ToASCII(v)
-}
-
-func isASCII(s string) bool {
-	for i := 0; i < len(s); i++ {
-		if s[i] >= utf8.RuneSelf {
-			return false
-		}
-	}
-	return true
-}
-
-// matcher represents the matching rule for a given value in the NO_PROXY list
-type matcher interface {
-	// match returns true if the host and optional port or ip and optional port
-	// are allowed
-	match(host, port string, ip net.IP) bool
-}
-
-// allMatch matches on all possible inputs
-type allMatch struct{}
-
-func (a allMatch) match(host, port string, ip net.IP) bool {
-	return true
-}
-
-type cidrMatch struct {
-	cidr *net.IPNet
-}
-
-func (m cidrMatch) match(host, port string, ip net.IP) bool {
-	return m.cidr.Contains(ip)
-}
-
-type ipMatch struct {
-	ip   net.IP
-	port string
-}
-
-func (m ipMatch) match(host, port string, ip net.IP) bool {
-	if m.ip.Equal(ip) {
-		return m.port == "" || m.port == port
-	}
-	return false
-}
-
-type domainMatch struct {
-	host string
-	port string
-
-	matchHost bool
-}
-
-func (m domainMatch) match(host, port string, ip net.IP) bool {
-	if strings.HasSuffix(host, m.host) || (m.matchHost && host == m.host[1:]) {
-		return m.port == "" || m.port == port
-	}
-	return false
-}
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/idna/trieval.go b/contrib/go/_std_1.18/src/vendor/golang.org/x/net/idna/trieval.go
deleted file mode 100644
index 7a8cf889b5..0000000000
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/idna/trieval.go
+++ /dev/null
@@ -1,119 +0,0 @@
-// Code generated by running "go generate" in golang.org/x/text. DO NOT EDIT.
-
-package idna
-
-// This file contains definitions for interpreting the trie value of the idna
-// trie generated by "go run gen*.go". It is shared by both the generator
-// program and the resultant package. Sharing is achieved by the generator
-// copying gen_trieval.go to trieval.go and changing what's above this comment.
-
-// info holds information from the IDNA mapping table for a single rune. It is
-// the value returned by a trie lookup. In most cases, all information fits in
-// a 16-bit value. For mappings, this value may contain an index into a slice
-// with the mapped string. Such mappings can consist of the actual mapped value
-// or an XOR pattern to be applied to the bytes of the UTF8 encoding of the
-// input rune. This technique is used by the cases packages and reduces the
-// table size significantly.
-//
-// The per-rune values have the following format:
-//
-//   if mapped {
-//     if inlinedXOR {
-//       15..13 inline XOR marker
-//       12..11 unused
-//       10..3  inline XOR mask
-//     } else {
-//       15..3  index into xor or mapping table
-//     }
-//   } else {
-//       15..14 unused
-//       13     mayNeedNorm
-//       12..11 attributes
-//       10..8  joining type
-//        7..3  category type
-//   }
-//      2  use xor pattern
-//   1..0  mapped category
-//
-// See the definitions below for a more detailed description of the various
-// bits.
-type info uint16
-
-const (
-	catSmallMask = 0x3
-	catBigMask   = 0xF8
-	indexShift   = 3
-	xorBit       = 0x4    // interpret the index as an xor pattern
-	inlineXOR    = 0xE000 // These bits are set if the XOR pattern is inlined.
-
-	joinShift = 8
-	joinMask  = 0x07
-
-	// Attributes
-	attributesMask = 0x1800
-	viramaModifier = 0x1800
-	modifier       = 0x1000
-	rtl            = 0x0800
-
-	mayNeedNorm = 0x2000
-)
-
-// A category corresponds to a category defined in the IDNA mapping table.
-type category uint16
-
-const (
-	unknown              category = 0 // not currently defined in unicode.
-	mapped               category = 1
-	disallowedSTD3Mapped category = 2
-	deviation            category = 3
-)
-
-const (
-	valid               category = 0x08
-	validNV8            category = 0x18
-	validXV8            category = 0x28
-	disallowed          category = 0x40
-	disallowedSTD3Valid category = 0x80
-	ignored             category = 0xC0
-)
-
-// join types and additional rune information
-const (
-	joiningL = (iota + 1)
-	joiningD
-	joiningT
-	joiningR
-
-	//the following types are derived during processing
-	joinZWJ
-	joinZWNJ
-	joinVirama
-	numJoinTypes
-)
-
-func (c info) isMapped() bool {
-	return c&0x3 != 0
-}
-
-func (c info) category() category {
-	small := c & catSmallMask
-	if small != 0 {
-		return category(small)
-	}
-	return category(c & catBigMask)
-}
-
-func (c info) joinType() info {
-	if c.isMapped() {
-		return 0
-	}
-	return (c >> joinShift) & joinMask
-}
-
-func (c info) isModifier() bool {
-	return c&(modifier|catSmallMask) == modifier
-}
-
-func (c info) isViramaModifier() bool {
-	return c&(attributesMask|catSmallMask) == viramaModifier
-}
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/sys/cpu/byteorder.go b/contrib/go/_std_1.18/src/vendor/golang.org/x/sys/cpu/byteorder.go
deleted file mode 100644
index dcbb14ef35..0000000000
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/sys/cpu/byteorder.go
+++ /dev/null
@@ -1,65 +0,0 @@
-// Copyright 2019 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cpu
-
-import (
-	"runtime"
-)
-
-// byteOrder is a subset of encoding/binary.ByteOrder.
-type byteOrder interface {
-	Uint32([]byte) uint32
-	Uint64([]byte) uint64
-}
-
-type littleEndian struct{}
-type bigEndian struct{}
-
-func (littleEndian) Uint32(b []byte) uint32 {
-	_ = b[3] // bounds check hint to compiler; see golang.org/issue/14808
-	return uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24
-}
-
-func (littleEndian) Uint64(b []byte) uint64 {
-	_ = b[7] // bounds check hint to compiler; see golang.org/issue/14808
-	return uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 |
-		uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56
-}
-
-func (bigEndian) Uint32(b []byte) uint32 {
-	_ = b[3] // bounds check hint to compiler; see golang.org/issue/14808
-	return uint32(b[3]) | uint32(b[2])<<8 | uint32(b[1])<<16 | uint32(b[0])<<24
-}
-
-func (bigEndian) Uint64(b []byte) uint64 {
-	_ = b[7] // bounds check hint to compiler; see golang.org/issue/14808
-	return uint64(b[7]) | uint64(b[6])<<8 | uint64(b[5])<<16 | uint64(b[4])<<24 |
-		uint64(b[3])<<32 | uint64(b[2])<<40 | uint64(b[1])<<48 | uint64(b[0])<<56
-}
-
-// hostByteOrder returns littleEndian on little-endian machines and
-// bigEndian on big-endian machines.
-func hostByteOrder() byteOrder {
-	switch runtime.GOARCH {
-	case "386", "amd64", "amd64p32",
-		"alpha",
-		"arm", "arm64",
-		"mipsle", "mips64le", "mips64p32le",
-		"nios2",
-		"ppc64le",
-		"riscv", "riscv64",
-		"sh":
-		return littleEndian{}
-	case "armbe", "arm64be",
-		"m68k",
-		"mips", "mips64", "mips64p32",
-		"ppc", "ppc64",
-		"s390", "s390x",
-		"shbe",
-		"sparc", "sparc64":
-		return bigEndian{}
-	}
-	panic("unknown architecture")
-}
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/sys/cpu/cpu.go b/contrib/go/_std_1.18/src/vendor/golang.org/x/sys/cpu/cpu.go
deleted file mode 100644
index b56886f261..0000000000
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/sys/cpu/cpu.go
+++ /dev/null
@@ -1,287 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package cpu implements processor feature detection for
-// various CPU architectures.
-package cpu
-
-import (
-	"os"
-	"strings"
-)
-
-// Initialized reports whether the CPU features were initialized.
-//
-// For some GOOS/GOARCH combinations initialization of the CPU features depends
-// on reading an operating specific file, e.g. /proc/self/auxv on linux/arm
-// Initialized will report false if reading the file fails.
-var Initialized bool
-
-// CacheLinePad is used to pad structs to avoid false sharing.
-type CacheLinePad struct{ _ [cacheLineSize]byte }
-
-// X86 contains the supported CPU features of the
-// current X86/AMD64 platform. If the current platform
-// is not X86/AMD64 then all feature flags are false.
-//
-// X86 is padded to avoid false sharing. Further the HasAVX
-// and HasAVX2 are only set if the OS supports XMM and YMM
-// registers in addition to the CPUID feature bit being set.
-var X86 struct {
-	_                   CacheLinePad
-	HasAES              bool // AES hardware implementation (AES NI)
-	HasADX              bool // Multi-precision add-carry instruction extensions
-	HasAVX              bool // Advanced vector extension
-	HasAVX2             bool // Advanced vector extension 2
-	HasAVX512           bool // Advanced vector extension 512
-	HasAVX512F          bool // Advanced vector extension 512 Foundation Instructions
-	HasAVX512CD         bool // Advanced vector extension 512 Conflict Detection Instructions
-	HasAVX512ER         bool // Advanced vector extension 512 Exponential and Reciprocal Instructions
-	HasAVX512PF         bool // Advanced vector extension 512 Prefetch Instructions Instructions
-	HasAVX512VL         bool // Advanced vector extension 512 Vector Length Extensions
-	HasAVX512BW         bool // Advanced vector extension 512 Byte and Word Instructions
-	HasAVX512DQ         bool // Advanced vector extension 512 Doubleword and Quadword Instructions
-	HasAVX512IFMA       bool // Advanced vector extension 512 Integer Fused Multiply Add
-	HasAVX512VBMI       bool // Advanced vector extension 512 Vector Byte Manipulation Instructions
-	HasAVX5124VNNIW     bool // Advanced vector extension 512 Vector Neural Network Instructions Word variable precision
-	HasAVX5124FMAPS     bool // Advanced vector extension 512 Fused Multiply Accumulation Packed Single precision
-	HasAVX512VPOPCNTDQ  bool // Advanced vector extension 512 Double and quad word population count instructions
-	HasAVX512VPCLMULQDQ bool // Advanced vector extension 512 Vector carry-less multiply operations
-	HasAVX512VNNI       bool // Advanced vector extension 512 Vector Neural Network Instructions
-	HasAVX512GFNI       bool // Advanced vector extension 512 Galois field New Instructions
-	HasAVX512VAES       bool // Advanced vector extension 512 Vector AES instructions
-	HasAVX512VBMI2      bool // Advanced vector extension 512 Vector Byte Manipulation Instructions 2
-	HasAVX512BITALG     bool // Advanced vector extension 512 Bit Algorithms
-	HasAVX512BF16       bool // Advanced vector extension 512 BFloat16 Instructions
-	HasBMI1             bool // Bit manipulation instruction set 1
-	HasBMI2             bool // Bit manipulation instruction set 2
-	HasCX16             bool // Compare and exchange 16 Bytes
-	HasERMS             bool // Enhanced REP for MOVSB and STOSB
-	HasFMA              bool // Fused-multiply-add instructions
-	HasOSXSAVE          bool // OS supports XSAVE/XRESTOR for saving/restoring XMM registers.
-	HasPCLMULQDQ        bool // PCLMULQDQ instruction - most often used for AES-GCM
-	HasPOPCNT           bool // Hamming weight instruction POPCNT.
-	HasRDRAND           bool // RDRAND instruction (on-chip random number generator)
-	HasRDSEED           bool // RDSEED instruction (on-chip random number generator)
-	HasSSE2             bool // Streaming SIMD extension 2 (always available on amd64)
-	HasSSE3             bool // Streaming SIMD extension 3
-	HasSSSE3            bool // Supplemental streaming SIMD extension 3
-	HasSSE41            bool // Streaming SIMD extension 4 and 4.1
-	HasSSE42            bool // Streaming SIMD extension 4 and 4.2
-	_                   CacheLinePad
-}
-
-// ARM64 contains the supported CPU features of the
-// current ARMv8(aarch64) platform. If the current platform
-// is not arm64 then all feature flags are false.
-var ARM64 struct {
-	_           CacheLinePad
-	HasFP       bool // Floating-point instruction set (always available)
-	HasASIMD    bool // Advanced SIMD (always available)
-	HasEVTSTRM  bool // Event stream support
-	HasAES      bool // AES hardware implementation
-	HasPMULL    bool // Polynomial multiplication instruction set
-	HasSHA1     bool // SHA1 hardware implementation
-	HasSHA2     bool // SHA2 hardware implementation
-	HasCRC32    bool // CRC32 hardware implementation
-	HasATOMICS  bool // Atomic memory operation instruction set
-	HasFPHP     bool // Half precision floating-point instruction set
-	HasASIMDHP  bool // Advanced SIMD half precision instruction set
-	HasCPUID    bool // CPUID identification scheme registers
-	HasASIMDRDM bool // Rounding double multiply add/subtract instruction set
-	HasJSCVT    bool // Javascript conversion from floating-point to integer
-	HasFCMA     bool // Floating-point multiplication and addition of complex numbers
-	HasLRCPC    bool // Release Consistent processor consistent support
-	HasDCPOP    bool // Persistent memory support
-	HasSHA3     bool // SHA3 hardware implementation
-	HasSM3      bool // SM3 hardware implementation
-	HasSM4      bool // SM4 hardware implementation
-	HasASIMDDP  bool // Advanced SIMD double precision instruction set
-	HasSHA512   bool // SHA512 hardware implementation
-	HasSVE      bool // Scalable Vector Extensions
-	HasASIMDFHM bool // Advanced SIMD multiplication FP16 to FP32
-	_           CacheLinePad
-}
-
-// ARM contains the supported CPU features of the current ARM (32-bit) platform.
-// All feature flags are false if:
-//   1. the current platform is not arm, or
-//   2. the current operating system is not Linux.
-var ARM struct {
-	_           CacheLinePad
-	HasSWP      bool // SWP instruction support
-	HasHALF     bool // Half-word load and store support
-	HasTHUMB    bool // ARM Thumb instruction set
-	Has26BIT    bool // Address space limited to 26-bits
-	HasFASTMUL  bool // 32-bit operand, 64-bit result multiplication support
-	HasFPA      bool // Floating point arithmetic support
-	HasVFP      bool // Vector floating point support
-	HasEDSP     bool // DSP Extensions support
-	HasJAVA     bool // Java instruction set
-	HasIWMMXT   bool // Intel Wireless MMX technology support
-	HasCRUNCH   bool // MaverickCrunch context switching and handling
-	HasTHUMBEE  bool // Thumb EE instruction set
-	HasNEON     bool // NEON instruction set
-	HasVFPv3    bool // Vector floating point version 3 support
-	HasVFPv3D16 bool // Vector floating point version 3 D8-D15
-	HasTLS      bool // Thread local storage support
-	HasVFPv4    bool // Vector floating point version 4 support
-	HasIDIVA    bool // Integer divide instruction support in ARM mode
-	HasIDIVT    bool // Integer divide instruction support in Thumb mode
-	HasVFPD32   bool // Vector floating point version 3 D15-D31
-	HasLPAE     bool // Large Physical Address Extensions
-	HasEVTSTRM  bool // Event stream support
-	HasAES      bool // AES hardware implementation
-	HasPMULL    bool // Polynomial multiplication instruction set
-	HasSHA1     bool // SHA1 hardware implementation
-	HasSHA2     bool // SHA2 hardware implementation
-	HasCRC32    bool // CRC32 hardware implementation
-	_           CacheLinePad
-}
-
-// MIPS64X contains the supported CPU features of the current mips64/mips64le
-// platforms. If the current platform is not mips64/mips64le or the current
-// operating system is not Linux then all feature flags are false.
-var MIPS64X struct {
-	_      CacheLinePad
-	HasMSA bool // MIPS SIMD architecture
-	_      CacheLinePad
-}
-
-// PPC64 contains the supported CPU features of the current ppc64/ppc64le platforms.
-// If the current platform is not ppc64/ppc64le then all feature flags are false.
-//
-// For ppc64/ppc64le, it is safe to check only for ISA level starting on ISA v3.00,
-// since there are no optional categories. There are some exceptions that also
-// require kernel support to work (DARN, SCV), so there are feature bits for
-// those as well. The struct is padded to avoid false sharing.
-var PPC64 struct {
-	_        CacheLinePad
-	HasDARN  bool // Hardware random number generator (requires kernel enablement)
-	HasSCV   bool // Syscall vectored (requires kernel enablement)
-	IsPOWER8 bool // ISA v2.07 (POWER8)
-	IsPOWER9 bool // ISA v3.00 (POWER9), implies IsPOWER8
-	_        CacheLinePad
-}
-
-// S390X contains the supported CPU features of the current IBM Z
-// (s390x) platform. If the current platform is not IBM Z then all
-// feature flags are false.
-//
-// S390X is padded to avoid false sharing. Further HasVX is only set
-// if the OS supports vector registers in addition to the STFLE
-// feature bit being set.
-var S390X struct {
-	_         CacheLinePad
-	HasZARCH  bool // z/Architecture mode is active [mandatory]
-	HasSTFLE  bool // store facility list extended
-	HasLDISP  bool // long (20-bit) displacements
-	HasEIMM   bool // 32-bit immediates
-	HasDFP    bool // decimal floating point
-	HasETF3EH bool // ETF-3 enhanced
-	HasMSA    bool // message security assist (CPACF)
-	HasAES    bool // KM-AES{128,192,256} functions
-	HasAESCBC bool // KMC-AES{128,192,256} functions
-	HasAESCTR bool // KMCTR-AES{128,192,256} functions
-	HasAESGCM bool // KMA-GCM-AES{128,192,256} functions
-	HasGHASH  bool // KIMD-GHASH function
-	HasSHA1   bool // K{I,L}MD-SHA-1 functions
-	HasSHA256 bool // K{I,L}MD-SHA-256 functions
-	HasSHA512 bool // K{I,L}MD-SHA-512 functions
-	HasSHA3   bool // K{I,L}MD-SHA3-{224,256,384,512} and K{I,L}MD-SHAKE-{128,256} functions
-	HasVX     bool // vector facility
-	HasVXE    bool // vector-enhancements facility 1
-	_         CacheLinePad
-}
-
-func init() {
-	archInit()
-	initOptions()
-	processOptions()
-}
-
-// options contains the cpu debug options that can be used in GODEBUG.
-// Options are arch dependent and are added by the arch specific initOptions functions.
-// Features that are mandatory for the specific GOARCH should have the Required field set
-// (e.g. SSE2 on amd64).
-var options []option
-
-// Option names should be lower case. e.g. avx instead of AVX.
-type option struct {
-	Name      string
-	Feature   *bool
-	Specified bool // whether feature value was specified in GODEBUG
-	Enable    bool // whether feature should be enabled
-	Required  bool // whether feature is mandatory and can not be disabled
-}
-
-func processOptions() {
-	env := os.Getenv("GODEBUG")
-field:
-	for env != "" {
-		field := ""
-		i := strings.IndexByte(env, ',')
-		if i < 0 {
-			field, env = env, ""
-		} else {
-			field, env = env[:i], env[i+1:]
-		}
-		if len(field) < 4 || field[:4] != "cpu." {
-			continue
-		}
-		i = strings.IndexByte(field, '=')
-		if i < 0 {
-			print("GODEBUG sys/cpu: no value specified for \"", field, "\"\n")
-			continue
-		}
-		key, value := field[4:i], field[i+1:] // e.g. "SSE2", "on"
-
-		var enable bool
-		switch value {
-		case "on":
-			enable = true
-		case "off":
-			enable = false
-		default:
-			print("GODEBUG sys/cpu: value \"", value, "\" not supported for cpu option \"", key, "\"\n")
-			continue field
-		}
-
-		if key == "all" {
-			for i := range options {
-				options[i].Specified = true
-				options[i].Enable = enable || options[i].Required
-			}
-			continue field
-		}
-
-		for i := range options {
-			if options[i].Name == key {
-				options[i].Specified = true
-				options[i].Enable = enable
-				continue field
-			}
-		}
-
-		print("GODEBUG sys/cpu: unknown cpu feature \"", key, "\"\n")
-	}
-
-	for _, o := range options {
-		if !o.Specified {
-			continue
-		}
-
-		if o.Enable && !*o.Feature {
-			print("GODEBUG sys/cpu: can not enable \"", o.Name, "\", missing CPU support\n")
-			continue
-		}
-
-		if !o.Enable && o.Required {
-			print("GODEBUG sys/cpu: can not disable \"", o.Name, "\", required CPU feature\n")
-			continue
-		}
-
-		*o.Feature = o.Enable
-	}
-}
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/bidi/core.go b/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/bidi/core.go
deleted file mode 100644
index fde188a33b..0000000000
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/bidi/core.go
+++ /dev/null
@@ -1,1071 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package bidi
-
-import (
-	"fmt"
-	"log"
-)
-
-// This implementation is a port based on the reference implementation found at:
-// https://www.unicode.org/Public/PROGRAMS/BidiReferenceJava/
-//
-// described in Unicode Bidirectional Algorithm (UAX #9).
-//
-// Input:
-// There are two levels of input to the algorithm, since clients may prefer to
-// supply some information from out-of-band sources rather than relying on the
-// default behavior.
-//
-// - Bidi class array
-// - Bidi class array, with externally supplied base line direction
-//
-// Output:
-// Output is separated into several stages:
-//
-//  - levels array over entire paragraph
-//  - reordering array over entire paragraph
-//  - levels array over line
-//  - reordering array over line
-//
-// Note that for conformance to the Unicode Bidirectional Algorithm,
-// implementations are only required to generate correct reordering and
-// character directionality (odd or even levels) over a line. Generating
-// identical level arrays over a line is not required. Bidi explicit format
-// codes (LRE, RLE, LRO, RLO, PDF) and BN can be assigned arbitrary levels and
-// positions as long as the rest of the input is properly reordered.
-//
-// As the algorithm is defined to operate on a single paragraph at a time, this
-// implementation is written to handle single paragraphs. Thus rule P1 is
-// presumed by this implementation-- the data provided to the implementation is
-// assumed to be a single paragraph, and either contains no 'B' codes, or a
-// single 'B' code at the end of the input. 'B' is allowed as input to
-// illustrate how the algorithm assigns it a level.
-//
-// Also note that rules L3 and L4 depend on the rendering engine that uses the
-// result of the bidi algorithm. This implementation assumes that the rendering
-// engine expects combining marks in visual order (e.g. to the left of their
-// base character in RTL runs) and that it adjusts the glyphs used to render
-// mirrored characters that are in RTL runs so that they render appropriately.
-
-// level is the embedding level of a character. Even embedding levels indicate
-// left-to-right order and odd levels indicate right-to-left order. The special
-// level of -1 is reserved for undefined order.
-type level int8
-
-const implicitLevel level = -1
-
-// in returns if x is equal to any of the values in set.
-func (c Class) in(set ...Class) bool {
-	for _, s := range set {
-		if c == s {
-			return true
-		}
-	}
-	return false
-}
-
-// A paragraph contains the state of a paragraph.
-type paragraph struct {
-	initialTypes []Class
-
-	// Arrays of properties needed for paired bracket evaluation in N0
-	pairTypes  []bracketType // paired Bracket types for paragraph
-	pairValues []rune        // rune for opening bracket or pbOpen and pbClose; 0 for pbNone
-
-	embeddingLevel level // default: = implicitLevel;
-
-	// at the paragraph levels
-	resultTypes  []Class
-	resultLevels []level
-
-	// Index of matching PDI for isolate initiator characters. For other
-	// characters, the value of matchingPDI will be set to -1. For isolate
-	// initiators with no matching PDI, matchingPDI will be set to the length of
-	// the input string.
-	matchingPDI []int
-
-	// Index of matching isolate initiator for PDI characters. For other
-	// characters, and for PDIs with no matching isolate initiator, the value of
-	// matchingIsolateInitiator will be set to -1.
-	matchingIsolateInitiator []int
-}
-
-// newParagraph initializes a paragraph. The user needs to supply a few arrays
-// corresponding to the preprocessed text input. The types correspond to the
-// Unicode BiDi classes for each rune. pairTypes indicates the bracket type for
-// each rune. pairValues provides a unique bracket class identifier for each
-// rune (suggested is the rune of the open bracket for opening and matching
-// close brackets, after normalization). The embedding levels are optional, but
-// may be supplied to encode embedding levels of styled text.
-func newParagraph(types []Class, pairTypes []bracketType, pairValues []rune, levels level) (*paragraph, error) {
-	var err error
-	if err = validateTypes(types); err != nil {
-		return nil, err
-	}
-	if err = validatePbTypes(pairTypes); err != nil {
-		return nil, err
-	}
-	if err = validatePbValues(pairValues, pairTypes); err != nil {
-		return nil, err
-	}
-	if err = validateParagraphEmbeddingLevel(levels); err != nil {
-		return nil, err
-	}
-
-	p := &paragraph{
-		initialTypes:   append([]Class(nil), types...),
-		embeddingLevel: levels,
-
-		pairTypes:  pairTypes,
-		pairValues: pairValues,
-
-		resultTypes: append([]Class(nil), types...),
-	}
-	p.run()
-	return p, nil
-}
-
-func (p *paragraph) Len() int { return len(p.initialTypes) }
-
-// The algorithm. Does not include line-based processing (Rules L1, L2).
-// These are applied later in the line-based phase of the algorithm.
-func (p *paragraph) run() {
-	p.determineMatchingIsolates()
-
-	// 1) determining the paragraph level
-	// Rule P1 is the requirement for entering this algorithm.
-	// Rules P2, P3.
-	// If no externally supplied paragraph embedding level, use default.
-	if p.embeddingLevel == implicitLevel {
-		p.embeddingLevel = p.determineParagraphEmbeddingLevel(0, p.Len())
-	}
-
-	// Initialize result levels to paragraph embedding level.
-	p.resultLevels = make([]level, p.Len())
-	setLevels(p.resultLevels, p.embeddingLevel)
-
-	// 2) Explicit levels and directions
-	// Rules X1-X8.
-	p.determineExplicitEmbeddingLevels()
-
-	// Rule X9.
-	// We do not remove the embeddings, the overrides, the PDFs, and the BNs
-	// from the string explicitly. But they are not copied into isolating run
-	// sequences when they are created, so they are removed for all
-	// practical purposes.
-
-	// Rule X10.
-	// Run remainder of algorithm one isolating run sequence at a time
-	for _, seq := range p.determineIsolatingRunSequences() {
-		// 3) resolving weak types
-		// Rules W1-W7.
-		seq.resolveWeakTypes()
-
-		// 4a) resolving paired brackets
-		// Rule N0
-		resolvePairedBrackets(seq)
-
-		// 4b) resolving neutral types
-		// Rules N1-N3.
-		seq.resolveNeutralTypes()
-
-		// 5) resolving implicit embedding levels
-		// Rules I1, I2.
-		seq.resolveImplicitLevels()
-
-		// Apply the computed levels and types
-		seq.applyLevelsAndTypes()
-	}
-
-	// Assign appropriate levels to 'hide' LREs, RLEs, LROs, RLOs, PDFs, and
-	// BNs. This is for convenience, so the resulting level array will have
-	// a value for every character.
-	p.assignLevelsToCharactersRemovedByX9()
-}
-
-// determineMatchingIsolates determines the matching PDI for each isolate
-// initiator and vice versa.
-//
-// Definition BD9.
-//
-// At the end of this function:
-//
-//  - The member variable matchingPDI is set to point to the index of the
-//    matching PDI character for each isolate initiator character. If there is
-//    no matching PDI, it is set to the length of the input text. For other
-//    characters, it is set to -1.
-//  - The member variable matchingIsolateInitiator is set to point to the
-//    index of the matching isolate initiator character for each PDI character.
-//    If there is no matching isolate initiator, or the character is not a PDI,
-//    it is set to -1.
-func (p *paragraph) determineMatchingIsolates() {
-	p.matchingPDI = make([]int, p.Len())
-	p.matchingIsolateInitiator = make([]int, p.Len())
-
-	for i := range p.matchingIsolateInitiator {
-		p.matchingIsolateInitiator[i] = -1
-	}
-
-	for i := range p.matchingPDI {
-		p.matchingPDI[i] = -1
-
-		if t := p.resultTypes[i]; t.in(LRI, RLI, FSI) {
-			depthCounter := 1
-			for j := i + 1; j < p.Len(); j++ {
-				if u := p.resultTypes[j]; u.in(LRI, RLI, FSI) {
-					depthCounter++
-				} else if u == PDI {
-					if depthCounter--; depthCounter == 0 {
-						p.matchingPDI[i] = j
-						p.matchingIsolateInitiator[j] = i
-						break
-					}
-				}
-			}
-			if p.matchingPDI[i] == -1 {
-				p.matchingPDI[i] = p.Len()
-			}
-		}
-	}
-}
-
-// determineParagraphEmbeddingLevel reports the resolved paragraph direction of
-// the substring limited by the given range [start, end).
-//
-// Determines the paragraph level based on rules P2, P3. This is also used
-// in rule X5c to find if an FSI should resolve to LRI or RLI.
-func (p *paragraph) determineParagraphEmbeddingLevel(start, end int) level {
-	var strongType Class = unknownClass
-
-	// Rule P2.
-	for i := start; i < end; i++ {
-		if t := p.resultTypes[i]; t.in(L, AL, R) {
-			strongType = t
-			break
-		} else if t.in(FSI, LRI, RLI) {
-			i = p.matchingPDI[i] // skip over to the matching PDI
-			if i > end {
-				log.Panic("assert (i <= end)")
-			}
-		}
-	}
-	// Rule P3.
-	switch strongType {
-	case unknownClass: // none found
-		// default embedding level when no strong types found is 0.
-		return 0
-	case L:
-		return 0
-	default: // AL, R
-		return 1
-	}
-}
-
-const maxDepth = 125
-
-// This stack will store the embedding levels and override and isolated
-// statuses
-type directionalStatusStack struct {
-	stackCounter        int
-	embeddingLevelStack [maxDepth + 1]level
-	overrideStatusStack [maxDepth + 1]Class
-	isolateStatusStack  [maxDepth + 1]bool
-}
-
-func (s *directionalStatusStack) empty()     { s.stackCounter = 0 }
-func (s *directionalStatusStack) pop()       { s.stackCounter-- }
-func (s *directionalStatusStack) depth() int { return s.stackCounter }
-
-func (s *directionalStatusStack) push(level level, overrideStatus Class, isolateStatus bool) {
-	s.embeddingLevelStack[s.stackCounter] = level
-	s.overrideStatusStack[s.stackCounter] = overrideStatus
-	s.isolateStatusStack[s.stackCounter] = isolateStatus
-	s.stackCounter++
-}
-
-func (s *directionalStatusStack) lastEmbeddingLevel() level {
-	return s.embeddingLevelStack[s.stackCounter-1]
-}
-
-func (s *directionalStatusStack) lastDirectionalOverrideStatus() Class {
-	return s.overrideStatusStack[s.stackCounter-1]
-}
-
-func (s *directionalStatusStack) lastDirectionalIsolateStatus() bool {
-	return s.isolateStatusStack[s.stackCounter-1]
-}
-
-// Determine explicit levels using rules X1 - X8
-func (p *paragraph) determineExplicitEmbeddingLevels() {
-	var stack directionalStatusStack
-	var overflowIsolateCount, overflowEmbeddingCount, validIsolateCount int
-
-	// Rule X1.
-	stack.push(p.embeddingLevel, ON, false)
-
-	for i, t := range p.resultTypes {
-		// Rules X2, X3, X4, X5, X5a, X5b, X5c
-		switch t {
-		case RLE, LRE, RLO, LRO, RLI, LRI, FSI:
-			isIsolate := t.in(RLI, LRI, FSI)
-			isRTL := t.in(RLE, RLO, RLI)
-
-			// override if this is an FSI that resolves to RLI
-			if t == FSI {
-				isRTL = (p.determineParagraphEmbeddingLevel(i+1, p.matchingPDI[i]) == 1)
-			}
-			if isIsolate {
-				p.resultLevels[i] = stack.lastEmbeddingLevel()
-				if stack.lastDirectionalOverrideStatus() != ON {
-					p.resultTypes[i] = stack.lastDirectionalOverrideStatus()
-				}
-			}
-
-			var newLevel level
-			if isRTL {
-				// least greater odd
-				newLevel = (stack.lastEmbeddingLevel() + 1) | 1
-			} else {
-				// least greater even
-				newLevel = (stack.lastEmbeddingLevel() + 2) &^ 1
-			}
-
-			if newLevel <= maxDepth && overflowIsolateCount == 0 && overflowEmbeddingCount == 0 {
-				if isIsolate {
-					validIsolateCount++
-				}
-				// Push new embedding level, override status, and isolated
-				// status.
-				// No check for valid stack counter, since the level check
-				// suffices.
-				switch t {
-				case LRO:
-					stack.push(newLevel, L, isIsolate)
-				case RLO:
-					stack.push(newLevel, R, isIsolate)
-				default:
-					stack.push(newLevel, ON, isIsolate)
-				}
-				// Not really part of the spec
-				if !isIsolate {
-					p.resultLevels[i] = newLevel
-				}
-			} else {
-				// This is an invalid explicit formatting character,
-				// so apply the "Otherwise" part of rules X2-X5b.
-				if isIsolate {
-					overflowIsolateCount++
-				} else { // !isIsolate
-					if overflowIsolateCount == 0 {
-						overflowEmbeddingCount++
-					}
-				}
-			}
-
-		// Rule X6a
-		case PDI:
-			if overflowIsolateCount > 0 {
-				overflowIsolateCount--
-			} else if validIsolateCount == 0 {
-				// do nothing
-			} else {
-				overflowEmbeddingCount = 0
-				for !stack.lastDirectionalIsolateStatus() {
-					stack.pop()
-				}
-				stack.pop()
-				validIsolateCount--
-			}
-			p.resultLevels[i] = stack.lastEmbeddingLevel()
-
-		// Rule X7
-		case PDF:
-			// Not really part of the spec
-			p.resultLevels[i] = stack.lastEmbeddingLevel()
-
-			if overflowIsolateCount > 0 {
-				// do nothing
-			} else if overflowEmbeddingCount > 0 {
-				overflowEmbeddingCount--
-			} else if !stack.lastDirectionalIsolateStatus() && stack.depth() >= 2 {
-				stack.pop()
-			}
-
-		case B: // paragraph separator.
-			// Rule X8.
-
-			// These values are reset for clarity, in this implementation B
-			// can only occur as the last code in the array.
-			stack.empty()
-			overflowIsolateCount = 0
-			overflowEmbeddingCount = 0
-			validIsolateCount = 0
-			p.resultLevels[i] = p.embeddingLevel
-
-		default:
-			p.resultLevels[i] = stack.lastEmbeddingLevel()
-			if stack.lastDirectionalOverrideStatus() != ON {
-				p.resultTypes[i] = stack.lastDirectionalOverrideStatus()
-			}
-		}
-	}
-}
-
-type isolatingRunSequence struct {
-	p *paragraph
-
-	indexes []int // indexes to the original string
-
-	types          []Class // type of each character using the index
-	resolvedLevels []level // resolved levels after application of rules
-	level          level
-	sos, eos       Class
-}
-
-func (i *isolatingRunSequence) Len() int { return len(i.indexes) }
-
-func maxLevel(a, b level) level {
-	if a > b {
-		return a
-	}
-	return b
-}
-
-// Rule X10, second bullet: Determine the start-of-sequence (sos) and end-of-sequence (eos) types,
-// 			 either L or R, for each isolating run sequence.
-func (p *paragraph) isolatingRunSequence(indexes []int) *isolatingRunSequence {
-	length := len(indexes)
-	types := make([]Class, length)
-	for i, x := range indexes {
-		types[i] = p.resultTypes[x]
-	}
-
-	// assign level, sos and eos
-	prevChar := indexes[0] - 1
-	for prevChar >= 0 && isRemovedByX9(p.initialTypes[prevChar]) {
-		prevChar--
-	}
-	prevLevel := p.embeddingLevel
-	if prevChar >= 0 {
-		prevLevel = p.resultLevels[prevChar]
-	}
-
-	var succLevel level
-	lastType := types[length-1]
-	if lastType.in(LRI, RLI, FSI) {
-		succLevel = p.embeddingLevel
-	} else {
-		// the first character after the end of run sequence
-		limit := indexes[length-1] + 1
-		for ; limit < p.Len() && isRemovedByX9(p.initialTypes[limit]); limit++ {
-
-		}
-		succLevel = p.embeddingLevel
-		if limit < p.Len() {
-			succLevel = p.resultLevels[limit]
-		}
-	}
-	level := p.resultLevels[indexes[0]]
-	return &isolatingRunSequence{
-		p:       p,
-		indexes: indexes,
-		types:   types,
-		level:   level,
-		sos:     typeForLevel(maxLevel(prevLevel, level)),
-		eos:     typeForLevel(maxLevel(succLevel, level)),
-	}
-}
-
-// Resolving weak types Rules W1-W7.
-//
-// Note that some weak types (EN, AN) remain after this processing is
-// complete.
-func (s *isolatingRunSequence) resolveWeakTypes() {
-
-	// on entry, only these types remain
-	s.assertOnly(L, R, AL, EN, ES, ET, AN, CS, B, S, WS, ON, NSM, LRI, RLI, FSI, PDI)
-
-	// Rule W1.
-	// Changes all NSMs.
-	precedingCharacterType := s.sos
-	for i, t := range s.types {
-		if t == NSM {
-			s.types[i] = precedingCharacterType
-		} else {
-			// if t.in(LRI, RLI, FSI, PDI) {
-			// 	precedingCharacterType = ON
-			// }
-			precedingCharacterType = t
-		}
-	}
-
-	// Rule W2.
-	// EN does not change at the start of the run, because sos != AL.
-	for i, t := range s.types {
-		if t == EN {
-			for j := i - 1; j >= 0; j-- {
-				if t := s.types[j]; t.in(L, R, AL) {
-					if t == AL {
-						s.types[i] = AN
-					}
-					break
-				}
-			}
-		}
-	}
-
-	// Rule W3.
-	for i, t := range s.types {
-		if t == AL {
-			s.types[i] = R
-		}
-	}
-
-	// Rule W4.
-	// Since there must be values on both sides for this rule to have an
-	// effect, the scan skips the first and last value.
-	//
-	// Although the scan proceeds left to right, and changes the type
-	// values in a way that would appear to affect the computations
-	// later in the scan, there is actually no problem. A change in the
-	// current value can only affect the value to its immediate right,
-	// and only affect it if it is ES or CS. But the current value can
-	// only change if the value to its right is not ES or CS. Thus
-	// either the current value will not change, or its change will have
-	// no effect on the remainder of the analysis.
-
-	for i := 1; i < s.Len()-1; i++ {
-		t := s.types[i]
-		if t == ES || t == CS {
-			prevSepType := s.types[i-1]
-			succSepType := s.types[i+1]
-			if prevSepType == EN && succSepType == EN {
-				s.types[i] = EN
-			} else if s.types[i] == CS && prevSepType == AN && succSepType == AN {
-				s.types[i] = AN
-			}
-		}
-	}
-
-	// Rule W5.
-	for i, t := range s.types {
-		if t == ET {
-			// locate end of sequence
-			runStart := i
-			runEnd := s.findRunLimit(runStart, ET)
-
-			// check values at ends of sequence
-			t := s.sos
-			if runStart > 0 {
-				t = s.types[runStart-1]
-			}
-			if t != EN {
-				t = s.eos
-				if runEnd < len(s.types) {
-					t = s.types[runEnd]
-				}
-			}
-			if t == EN {
-				setTypes(s.types[runStart:runEnd], EN)
-			}
-			// continue at end of sequence
-			i = runEnd
-		}
-	}
-
-	// Rule W6.
-	for i, t := range s.types {
-		if t.in(ES, ET, CS) {
-			s.types[i] = ON
-		}
-	}
-
-	// Rule W7.
-	for i, t := range s.types {
-		if t == EN {
-			// set default if we reach start of run
-			prevStrongType := s.sos
-			for j := i - 1; j >= 0; j-- {
-				t = s.types[j]
-				if t == L || t == R { // AL's have been changed to R
-					prevStrongType = t
-					break
-				}
-			}
-			if prevStrongType == L {
-				s.types[i] = L
-			}
-		}
-	}
-}
-
-// 6) resolving neutral types Rules N1-N2.
-func (s *isolatingRunSequence) resolveNeutralTypes() {
-
-	// on entry, only these types can be in resultTypes
-	s.assertOnly(L, R, EN, AN, B, S, WS, ON, RLI, LRI, FSI, PDI)
-
-	for i, t := range s.types {
-		switch t {
-		case WS, ON, B, S, RLI, LRI, FSI, PDI:
-			// find bounds of run of neutrals
-			runStart := i
-			runEnd := s.findRunLimit(runStart, B, S, WS, ON, RLI, LRI, FSI, PDI)
-
-			// determine effective types at ends of run
-			var leadType, trailType Class
-
-			// Note that the character found can only be L, R, AN, or
-			// EN.
-			if runStart == 0 {
-				leadType = s.sos
-			} else {
-				leadType = s.types[runStart-1]
-				if leadType.in(AN, EN) {
-					leadType = R
-				}
-			}
-			if runEnd == len(s.types) {
-				trailType = s.eos
-			} else {
-				trailType = s.types[runEnd]
-				if trailType.in(AN, EN) {
-					trailType = R
-				}
-			}
-
-			var resolvedType Class
-			if leadType == trailType {
-				// Rule N1.
-				resolvedType = leadType
-			} else {
-				// Rule N2.
-				// Notice the embedding level of the run is used, not
-				// the paragraph embedding level.
-				resolvedType = typeForLevel(s.level)
-			}
-
-			setTypes(s.types[runStart:runEnd], resolvedType)
-
-			// skip over run of (former) neutrals
-			i = runEnd
-		}
-	}
-}
-
-func setLevels(levels []level, newLevel level) {
-	for i := range levels {
-		levels[i] = newLevel
-	}
-}
-
-func setTypes(types []Class, newType Class) {
-	for i := range types {
-		types[i] = newType
-	}
-}
-
-// 7) resolving implicit embedding levels Rules I1, I2.
-func (s *isolatingRunSequence) resolveImplicitLevels() {
-
-	// on entry, only these types can be in resultTypes
-	s.assertOnly(L, R, EN, AN)
-
-	s.resolvedLevels = make([]level, len(s.types))
-	setLevels(s.resolvedLevels, s.level)
-
-	if (s.level & 1) == 0 { // even level
-		for i, t := range s.types {
-			// Rule I1.
-			if t == L {
-				// no change
-			} else if t == R {
-				s.resolvedLevels[i] += 1
-			} else { // t == AN || t == EN
-				s.resolvedLevels[i] += 2
-			}
-		}
-	} else { // odd level
-		for i, t := range s.types {
-			// Rule I2.
-			if t == R {
-				// no change
-			} else { // t == L || t == AN || t == EN
-				s.resolvedLevels[i] += 1
-			}
-		}
-	}
-}
-
-// Applies the levels and types resolved in rules W1-I2 to the
-// resultLevels array.
-func (s *isolatingRunSequence) applyLevelsAndTypes() {
-	for i, x := range s.indexes {
-		s.p.resultTypes[x] = s.types[i]
-		s.p.resultLevels[x] = s.resolvedLevels[i]
-	}
-}
-
-// Return the limit of the run consisting only of the types in validSet
-// starting at index. This checks the value at index, and will return
-// index if that value is not in validSet.
-func (s *isolatingRunSequence) findRunLimit(index int, validSet ...Class) int {
-loop:
-	for ; index < len(s.types); index++ {
-		t := s.types[index]
-		for _, valid := range validSet {
-			if t == valid {
-				continue loop
-			}
-		}
-		return index // didn't find a match in validSet
-	}
-	return len(s.types)
-}
-
-// Algorithm validation. Assert that all values in types are in the
-// provided set.
-func (s *isolatingRunSequence) assertOnly(codes ...Class) {
-loop:
-	for i, t := range s.types {
-		for _, c := range codes {
-			if t == c {
-				continue loop
-			}
-		}
-		log.Panicf("invalid bidi code %v present in assertOnly at position %d", t, s.indexes[i])
-	}
-}
-
-// determineLevelRuns returns an array of level runs. Each level run is
-// described as an array of indexes into the input string.
-//
-// Determines the level runs. Rule X9 will be applied in determining the
-// runs, in the way that makes sure the characters that are supposed to be
-// removed are not included in the runs.
-func (p *paragraph) determineLevelRuns() [][]int {
-	run := []int{}
-	allRuns := [][]int{}
-	currentLevel := implicitLevel
-
-	for i := range p.initialTypes {
-		if !isRemovedByX9(p.initialTypes[i]) {
-			if p.resultLevels[i] != currentLevel {
-				// we just encountered a new run; wrap up last run
-				if currentLevel >= 0 { // only wrap it up if there was a run
-					allRuns = append(allRuns, run)
-					run = nil
-				}
-				// Start new run
-				currentLevel = p.resultLevels[i]
-			}
-			run = append(run, i)
-		}
-	}
-	// Wrap up the final run, if any
-	if len(run) > 0 {
-		allRuns = append(allRuns, run)
-	}
-	return allRuns
-}
-
-// Definition BD13. Determine isolating run sequences.
-func (p *paragraph) determineIsolatingRunSequences() []*isolatingRunSequence {
-	levelRuns := p.determineLevelRuns()
-
-	// Compute the run that each character belongs to
-	runForCharacter := make([]int, p.Len())
-	for i, run := range levelRuns {
-		for _, index := range run {
-			runForCharacter[index] = i
-		}
-	}
-
-	sequences := []*isolatingRunSequence{}
-
-	var currentRunSequence []int
-
-	for _, run := range levelRuns {
-		first := run[0]
-		if p.initialTypes[first] != PDI || p.matchingIsolateInitiator[first] == -1 {
-			currentRunSequence = nil
-			// int run = i;
-			for {
-				// Copy this level run into currentRunSequence
-				currentRunSequence = append(currentRunSequence, run...)
-
-				last := currentRunSequence[len(currentRunSequence)-1]
-				lastT := p.initialTypes[last]
-				if lastT.in(LRI, RLI, FSI) && p.matchingPDI[last] != p.Len() {
-					run = levelRuns[runForCharacter[p.matchingPDI[last]]]
-				} else {
-					break
-				}
-			}
-			sequences = append(sequences, p.isolatingRunSequence(currentRunSequence))
-		}
-	}
-	return sequences
-}
-
-// Assign level information to characters removed by rule X9. This is for
-// ease of relating the level information to the original input data. Note
-// that the levels assigned to these codes are arbitrary, they're chosen so
-// as to avoid breaking level runs.
-func (p *paragraph) assignLevelsToCharactersRemovedByX9() {
-	for i, t := range p.initialTypes {
-		if t.in(LRE, RLE, LRO, RLO, PDF, BN) {
-			p.resultTypes[i] = t
-			p.resultLevels[i] = -1
-		}
-	}
-	// now propagate forward the levels information (could have
-	// propagated backward, the main thing is not to introduce a level
-	// break where one doesn't already exist).
-
-	if p.resultLevels[0] == -1 {
-		p.resultLevels[0] = p.embeddingLevel
-	}
-	for i := 1; i < len(p.initialTypes); i++ {
-		if p.resultLevels[i] == -1 {
-			p.resultLevels[i] = p.resultLevels[i-1]
-		}
-	}
-	// Embedding information is for informational purposes only so need not be
-	// adjusted.
-}
-
-//
-// Output
-//
-
-// getLevels computes levels array breaking lines at offsets in linebreaks.
-// Rule L1.
-//
-// The linebreaks array must include at least one value. The values must be
-// in strictly increasing order (no duplicates) between 1 and the length of
-// the text, inclusive. The last value must be the length of the text.
-func (p *paragraph) getLevels(linebreaks []int) []level {
-	// Note that since the previous processing has removed all
-	// P, S, and WS values from resultTypes, the values referred to
-	// in these rules are the initial types, before any processing
-	// has been applied (including processing of overrides).
-	//
-	// This example implementation has reinserted explicit format codes
-	// and BN, in order that the levels array correspond to the
-	// initial text. Their final placement is not normative.
-	// These codes are treated like WS in this implementation,
-	// so they don't interrupt sequences of WS.
-
-	validateLineBreaks(linebreaks, p.Len())
-
-	result := append([]level(nil), p.resultLevels...)
-
-	// don't worry about linebreaks since if there is a break within
-	// a series of WS values preceding S, the linebreak itself
-	// causes the reset.
-	for i, t := range p.initialTypes {
-		if t.in(B, S) {
-			// Rule L1, clauses one and two.
-			result[i] = p.embeddingLevel
-
-			// Rule L1, clause three.
-			for j := i - 1; j >= 0; j-- {
-				if isWhitespace(p.initialTypes[j]) { // including format codes
-					result[j] = p.embeddingLevel
-				} else {
-					break
-				}
-			}
-		}
-	}
-
-	// Rule L1, clause four.
-	start := 0
-	for _, limit := range linebreaks {
-		for j := limit - 1; j >= start; j-- {
-			if isWhitespace(p.initialTypes[j]) { // including format codes
-				result[j] = p.embeddingLevel
-			} else {
-				break
-			}
-		}
-		start = limit
-	}
-
-	return result
-}
-
-// getReordering returns the reordering of lines from a visual index to a
-// logical index for line breaks at the given offsets.
-//
-// Lines are concatenated from left to right. So for example, the fifth
-// character from the left on the third line is
-//
-// 		getReordering(linebreaks)[linebreaks[1] + 4]
-//
-// (linebreaks[1] is the position after the last character of the second
-// line, which is also the index of the first character on the third line,
-// and adding four gets the fifth character from the left).
-//
-// The linebreaks array must include at least one value. The values must be
-// in strictly increasing order (no duplicates) between 1 and the length of
-// the text, inclusive. The last value must be the length of the text.
-func (p *paragraph) getReordering(linebreaks []int) []int {
-	validateLineBreaks(linebreaks, p.Len())
-
-	return computeMultilineReordering(p.getLevels(linebreaks), linebreaks)
-}
-
-// Return multiline reordering array for a given level array. Reordering
-// does not occur across a line break.
-func computeMultilineReordering(levels []level, linebreaks []int) []int {
-	result := make([]int, len(levels))
-
-	start := 0
-	for _, limit := range linebreaks {
-		tempLevels := make([]level, limit-start)
-		copy(tempLevels, levels[start:])
-
-		for j, order := range computeReordering(tempLevels) {
-			result[start+j] = order + start
-		}
-		start = limit
-	}
-	return result
-}
-
-// Return reordering array for a given level array. This reorders a single
-// line. The reordering is a visual to logical map. For example, the
-// leftmost char is string.charAt(order[0]). Rule L2.
-func computeReordering(levels []level) []int {
-	result := make([]int, len(levels))
-	// initialize order
-	for i := range result {
-		result[i] = i
-	}
-
-	// locate highest level found on line.
-	// Note the rules say text, but no reordering across line bounds is
-	// performed, so this is sufficient.
-	highestLevel := level(0)
-	lowestOddLevel := level(maxDepth + 2)
-	for _, level := range levels {
-		if level > highestLevel {
-			highestLevel = level
-		}
-		if level&1 != 0 && level < lowestOddLevel {
-			lowestOddLevel = level
-		}
-	}
-
-	for level := highestLevel; level >= lowestOddLevel; level-- {
-		for i := 0; i < len(levels); i++ {
-			if levels[i] >= level {
-				// find range of text at or above this level
-				start := i
-				limit := i + 1
-				for limit < len(levels) && levels[limit] >= level {
-					limit++
-				}
-
-				for j, k := start, limit-1; j < k; j, k = j+1, k-1 {
-					result[j], result[k] = result[k], result[j]
-				}
-				// skip to end of level run
-				i = limit
-			}
-		}
-	}
-
-	return result
-}
-
-// isWhitespace reports whether the type is considered a whitespace type for the
-// line break rules.
-func isWhitespace(c Class) bool {
-	switch c {
-	case LRE, RLE, LRO, RLO, PDF, LRI, RLI, FSI, PDI, BN, WS:
-		return true
-	}
-	return false
-}
-
-// isRemovedByX9 reports whether the type is one of the types removed in X9.
-func isRemovedByX9(c Class) bool {
-	switch c {
-	case LRE, RLE, LRO, RLO, PDF, BN:
-		return true
-	}
-	return false
-}
-
-// typeForLevel reports the strong type (L or R) corresponding to the level.
-func typeForLevel(level level) Class {
-	if (level & 0x1) == 0 {
-		return L
-	}
-	return R
-}
-
-func validateTypes(types []Class) error {
-	if len(types) == 0 {
-		return fmt.Errorf("types is null")
-	}
-	for i, t := range types[:len(types)-1] {
-		if t == B {
-			return fmt.Errorf("B type before end of paragraph at index: %d", i)
-		}
-	}
-	return nil
-}
-
-func validateParagraphEmbeddingLevel(embeddingLevel level) error {
-	if embeddingLevel != implicitLevel &&
-		embeddingLevel != 0 &&
-		embeddingLevel != 1 {
-		return fmt.Errorf("illegal paragraph embedding level: %d", embeddingLevel)
-	}
-	return nil
-}
-
-func validateLineBreaks(linebreaks []int, textLength int) error {
-	prev := 0
-	for i, next := range linebreaks {
-		if next <= prev {
-			return fmt.Errorf("bad linebreak: %d at index: %d", next, i)
-		}
-		prev = next
-	}
-	if prev != textLength {
-		return fmt.Errorf("last linebreak was %d, want %d", prev, textLength)
-	}
-	return nil
-}
-
-func validatePbTypes(pairTypes []bracketType) error {
-	if len(pairTypes) == 0 {
-		return fmt.Errorf("pairTypes is null")
-	}
-	for i, pt := range pairTypes {
-		switch pt {
-		case bpNone, bpOpen, bpClose:
-		default:
-			return fmt.Errorf("illegal pairType value at %d: %v", i, pairTypes[i])
-		}
-	}
-	return nil
-}
-
-func validatePbValues(pairValues []rune, pairTypes []bracketType) error {
-	if pairValues == nil {
-		return fmt.Errorf("pairValues is null")
-	}
-	if len(pairTypes) != len(pairValues) {
-		return fmt.Errorf("pairTypes is different length from pairValues")
-	}
-	return nil
-}
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/norm/forminfo.go b/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/norm/forminfo.go
deleted file mode 100644
index 526c7033ac..0000000000
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/norm/forminfo.go
+++ /dev/null
@@ -1,278 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package norm
-
-import "encoding/binary"
-
-// This file contains Form-specific logic and wrappers for data in tables.go.
-
-// Rune info is stored in a separate trie per composing form. A composing form
-// and its corresponding decomposing form share the same trie.  Each trie maps
-// a rune to a uint16. The values take two forms.  For v >= 0x8000:
-//   bits
-//   15:    1 (inverse of NFD_QC bit of qcInfo)
-//   13..7: qcInfo (see below). isYesD is always true (no decompostion).
-//    6..0: ccc (compressed CCC value).
-// For v < 0x8000, the respective rune has a decomposition and v is an index
-// into a byte array of UTF-8 decomposition sequences and additional info and
-// has the form:
-//    <header> <decomp_byte>* [<tccc> [<lccc>]]
-// The header contains the number of bytes in the decomposition (excluding this
-// length byte). The two most significant bits of this length byte correspond
-// to bit 5 and 4 of qcInfo (see below).  The byte sequence itself starts at v+1.
-// The byte sequence is followed by a trailing and leading CCC if the values
-// for these are not zero.  The value of v determines which ccc are appended
-// to the sequences.  For v < firstCCC, there are none, for v >= firstCCC,
-// the sequence is followed by a trailing ccc, and for v >= firstLeadingCC
-// there is an additional leading ccc. The value of tccc itself is the
-// trailing CCC shifted left 2 bits. The two least-significant bits of tccc
-// are the number of trailing non-starters.
-
-const (
-	qcInfoMask      = 0x3F // to clear all but the relevant bits in a qcInfo
-	headerLenMask   = 0x3F // extract the length value from the header byte
-	headerFlagsMask = 0xC0 // extract the qcInfo bits from the header byte
-)
-
-// Properties provides access to normalization properties of a rune.
-type Properties struct {
-	pos   uint8  // start position in reorderBuffer; used in composition.go
-	size  uint8  // length of UTF-8 encoding of this rune
-	ccc   uint8  // leading canonical combining class (ccc if not decomposition)
-	tccc  uint8  // trailing canonical combining class (ccc if not decomposition)
-	nLead uint8  // number of leading non-starters.
-	flags qcInfo // quick check flags
-	index uint16
-}
-
-// functions dispatchable per form
-type lookupFunc func(b input, i int) Properties
-
-// formInfo holds Form-specific functions and tables.
-type formInfo struct {
-	form                     Form
-	composing, compatibility bool // form type
-	info                     lookupFunc
-	nextMain                 iterFunc
-}
-
-var formTable = []*formInfo{{
-	form:          NFC,
-	composing:     true,
-	compatibility: false,
-	info:          lookupInfoNFC,
-	nextMain:      nextComposed,
-}, {
-	form:          NFD,
-	composing:     false,
-	compatibility: false,
-	info:          lookupInfoNFC,
-	nextMain:      nextDecomposed,
-}, {
-	form:          NFKC,
-	composing:     true,
-	compatibility: true,
-	info:          lookupInfoNFKC,
-	nextMain:      nextComposed,
-}, {
-	form:          NFKD,
-	composing:     false,
-	compatibility: true,
-	info:          lookupInfoNFKC,
-	nextMain:      nextDecomposed,
-}}
-
-// We do not distinguish between boundaries for NFC, NFD, etc. to avoid
-// unexpected behavior for the user.  For example, in NFD, there is a boundary
-// after 'a'.  However, 'a' might combine with modifiers, so from the application's
-// perspective it is not a good boundary. We will therefore always use the
-// boundaries for the combining variants.
-
-// BoundaryBefore returns true if this rune starts a new segment and
-// cannot combine with any rune on the left.
-func (p Properties) BoundaryBefore() bool {
-	if p.ccc == 0 && !p.combinesBackward() {
-		return true
-	}
-	// We assume that the CCC of the first character in a decomposition
-	// is always non-zero if different from info.ccc and that we can return
-	// false at this point. This is verified by maketables.
-	return false
-}
-
-// BoundaryAfter returns true if runes cannot combine with or otherwise
-// interact with this or previous runes.
-func (p Properties) BoundaryAfter() bool {
-	// TODO: loosen these conditions.
-	return p.isInert()
-}
-
-// We pack quick check data in 4 bits:
-//   5:    Combines forward  (0 == false, 1 == true)
-//   4..3: NFC_QC Yes(00), No (10), or Maybe (11)
-//   2:    NFD_QC Yes (0) or No (1). No also means there is a decomposition.
-//   1..0: Number of trailing non-starters.
-//
-// When all 4 bits are zero, the character is inert, meaning it is never
-// influenced by normalization.
-type qcInfo uint8
-
-func (p Properties) isYesC() bool { return p.flags&0x10 == 0 }
-func (p Properties) isYesD() bool { return p.flags&0x4 == 0 }
-
-func (p Properties) combinesForward() bool  { return p.flags&0x20 != 0 }
-func (p Properties) combinesBackward() bool { return p.flags&0x8 != 0 } // == isMaybe
-func (p Properties) hasDecomposition() bool { return p.flags&0x4 != 0 } // == isNoD
-
-func (p Properties) isInert() bool {
-	return p.flags&qcInfoMask == 0 && p.ccc == 0
-}
-
-func (p Properties) multiSegment() bool {
-	return p.index >= firstMulti && p.index < endMulti
-}
-
-func (p Properties) nLeadingNonStarters() uint8 {
-	return p.nLead
-}
-
-func (p Properties) nTrailingNonStarters() uint8 {
-	return uint8(p.flags & 0x03)
-}
-
-// Decomposition returns the decomposition for the underlying rune
-// or nil if there is none.
-func (p Properties) Decomposition() []byte {
-	// TODO: create the decomposition for Hangul?
-	if p.index == 0 {
-		return nil
-	}
-	i := p.index
-	n := decomps[i] & headerLenMask
-	i++
-	return decomps[i : i+uint16(n)]
-}
-
-// Size returns the length of UTF-8 encoding of the rune.
-func (p Properties) Size() int {
-	return int(p.size)
-}
-
-// CCC returns the canonical combining class of the underlying rune.
-func (p Properties) CCC() uint8 {
-	if p.index >= firstCCCZeroExcept {
-		return 0
-	}
-	return ccc[p.ccc]
-}
-
-// LeadCCC returns the CCC of the first rune in the decomposition.
-// If there is no decomposition, LeadCCC equals CCC.
-func (p Properties) LeadCCC() uint8 {
-	return ccc[p.ccc]
-}
-
-// TrailCCC returns the CCC of the last rune in the decomposition.
-// If there is no decomposition, TrailCCC equals CCC.
-func (p Properties) TrailCCC() uint8 {
-	return ccc[p.tccc]
-}
-
-func buildRecompMap() {
-	recompMap = make(map[uint32]rune, len(recompMapPacked)/8)
-	var buf [8]byte
-	for i := 0; i < len(recompMapPacked); i += 8 {
-		copy(buf[:], recompMapPacked[i:i+8])
-		key := binary.BigEndian.Uint32(buf[:4])
-		val := binary.BigEndian.Uint32(buf[4:])
-		recompMap[key] = rune(val)
-	}
-}
-
-// Recomposition
-// We use 32-bit keys instead of 64-bit for the two codepoint keys.
-// This clips off the bits of three entries, but we know this will not
-// result in a collision. In the unlikely event that changes to
-// UnicodeData.txt introduce collisions, the compiler will catch it.
-// Note that the recomposition map for NFC and NFKC are identical.
-
-// combine returns the combined rune or 0 if it doesn't exist.
-//
-// The caller is responsible for calling
-// recompMapOnce.Do(buildRecompMap) sometime before this is called.
-func combine(a, b rune) rune {
-	key := uint32(uint16(a))<<16 + uint32(uint16(b))
-	if recompMap == nil {
-		panic("caller error") // see func comment
-	}
-	return recompMap[key]
-}
-
-func lookupInfoNFC(b input, i int) Properties {
-	v, sz := b.charinfoNFC(i)
-	return compInfo(v, sz)
-}
-
-func lookupInfoNFKC(b input, i int) Properties {
-	v, sz := b.charinfoNFKC(i)
-	return compInfo(v, sz)
-}
-
-// Properties returns properties for the first rune in s.
-func (f Form) Properties(s []byte) Properties {
-	if f == NFC || f == NFD {
-		return compInfo(nfcData.lookup(s))
-	}
-	return compInfo(nfkcData.lookup(s))
-}
-
-// PropertiesString returns properties for the first rune in s.
-func (f Form) PropertiesString(s string) Properties {
-	if f == NFC || f == NFD {
-		return compInfo(nfcData.lookupString(s))
-	}
-	return compInfo(nfkcData.lookupString(s))
-}
-
-// compInfo converts the information contained in v and sz
-// to a Properties.  See the comment at the top of the file
-// for more information on the format.
-func compInfo(v uint16, sz int) Properties {
-	if v == 0 {
-		return Properties{size: uint8(sz)}
-	} else if v >= 0x8000 {
-		p := Properties{
-			size:  uint8(sz),
-			ccc:   uint8(v),
-			tccc:  uint8(v),
-			flags: qcInfo(v >> 8),
-		}
-		if p.ccc > 0 || p.combinesBackward() {
-			p.nLead = uint8(p.flags & 0x3)
-		}
-		return p
-	}
-	// has decomposition
-	h := decomps[v]
-	f := (qcInfo(h&headerFlagsMask) >> 2) | 0x4
-	p := Properties{size: uint8(sz), flags: f, index: v}
-	if v >= firstCCC {
-		v += uint16(h&headerLenMask) + 1
-		c := decomps[v]
-		p.tccc = c >> 2
-		p.flags |= qcInfo(c & 0x3)
-		if v >= firstLeadingCCC {
-			p.nLead = c & 0x3
-			if v >= firstStarterWithNLead {
-				// We were tricked. Remove the decomposition.
-				p.flags &= 0x03
-				p.index = 0
-				return p
-			}
-			p.ccc = decomps[v+1]
-		}
-	}
-	return p
-}
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/norm/normalize.go b/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/norm/normalize.go
deleted file mode 100644
index 95efcf26e8..0000000000
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/norm/normalize.go
+++ /dev/null
@@ -1,609 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Note: the file data_test.go that is generated should not be checked in.
-//go:generate go run maketables.go triegen.go
-//go:generate go test -tags test
-
-// Package norm contains types and functions for normalizing Unicode strings.
-package norm // import "golang.org/x/text/unicode/norm"
-
-import (
-	"unicode/utf8"
-
-	"golang.org/x/text/transform"
-)
-
-// A Form denotes a canonical representation of Unicode code points.
-// The Unicode-defined normalization and equivalence forms are:
-//
-//   NFC   Unicode Normalization Form C
-//   NFD   Unicode Normalization Form D
-//   NFKC  Unicode Normalization Form KC
-//   NFKD  Unicode Normalization Form KD
-//
-// For a Form f, this documentation uses the notation f(x) to mean
-// the bytes or string x converted to the given form.
-// A position n in x is called a boundary if conversion to the form can
-// proceed independently on both sides:
-//   f(x) == append(f(x[0:n]), f(x[n:])...)
-//
-// References: https://unicode.org/reports/tr15/ and
-// https://unicode.org/notes/tn5/.
-type Form int
-
-const (
-	NFC Form = iota
-	NFD
-	NFKC
-	NFKD
-)
-
-// Bytes returns f(b). May return b if f(b) = b.
-func (f Form) Bytes(b []byte) []byte {
-	src := inputBytes(b)
-	ft := formTable[f]
-	n, ok := ft.quickSpan(src, 0, len(b), true)
-	if ok {
-		return b
-	}
-	out := make([]byte, n, len(b))
-	copy(out, b[0:n])
-	rb := reorderBuffer{f: *ft, src: src, nsrc: len(b), out: out, flushF: appendFlush}
-	return doAppendInner(&rb, n)
-}
-
-// String returns f(s).
-func (f Form) String(s string) string {
-	src := inputString(s)
-	ft := formTable[f]
-	n, ok := ft.quickSpan(src, 0, len(s), true)
-	if ok {
-		return s
-	}
-	out := make([]byte, n, len(s))
-	copy(out, s[0:n])
-	rb := reorderBuffer{f: *ft, src: src, nsrc: len(s), out: out, flushF: appendFlush}
-	return string(doAppendInner(&rb, n))
-}
-
-// IsNormal returns true if b == f(b).
-func (f Form) IsNormal(b []byte) bool {
-	src := inputBytes(b)
-	ft := formTable[f]
-	bp, ok := ft.quickSpan(src, 0, len(b), true)
-	if ok {
-		return true
-	}
-	rb := reorderBuffer{f: *ft, src: src, nsrc: len(b)}
-	rb.setFlusher(nil, cmpNormalBytes)
-	for bp < len(b) {
-		rb.out = b[bp:]
-		if bp = decomposeSegment(&rb, bp, true); bp < 0 {
-			return false
-		}
-		bp, _ = rb.f.quickSpan(rb.src, bp, len(b), true)
-	}
-	return true
-}
-
-func cmpNormalBytes(rb *reorderBuffer) bool {
-	b := rb.out
-	for i := 0; i < rb.nrune; i++ {
-		info := rb.rune[i]
-		if int(info.size) > len(b) {
-			return false
-		}
-		p := info.pos
-		pe := p + info.size
-		for ; p < pe; p++ {
-			if b[0] != rb.byte[p] {
-				return false
-			}
-			b = b[1:]
-		}
-	}
-	return true
-}
-
-// IsNormalString returns true if s == f(s).
-func (f Form) IsNormalString(s string) bool {
-	src := inputString(s)
-	ft := formTable[f]
-	bp, ok := ft.quickSpan(src, 0, len(s), true)
-	if ok {
-		return true
-	}
-	rb := reorderBuffer{f: *ft, src: src, nsrc: len(s)}
-	rb.setFlusher(nil, func(rb *reorderBuffer) bool {
-		for i := 0; i < rb.nrune; i++ {
-			info := rb.rune[i]
-			if bp+int(info.size) > len(s) {
-				return false
-			}
-			p := info.pos
-			pe := p + info.size
-			for ; p < pe; p++ {
-				if s[bp] != rb.byte[p] {
-					return false
-				}
-				bp++
-			}
-		}
-		return true
-	})
-	for bp < len(s) {
-		if bp = decomposeSegment(&rb, bp, true); bp < 0 {
-			return false
-		}
-		bp, _ = rb.f.quickSpan(rb.src, bp, len(s), true)
-	}
-	return true
-}
-
-// patchTail fixes a case where a rune may be incorrectly normalized
-// if it is followed by illegal continuation bytes. It returns the
-// patched buffer and whether the decomposition is still in progress.
-func patchTail(rb *reorderBuffer) bool {
-	info, p := lastRuneStart(&rb.f, rb.out)
-	if p == -1 || info.size == 0 {
-		return true
-	}
-	end := p + int(info.size)
-	extra := len(rb.out) - end
-	if extra > 0 {
-		// Potentially allocating memory. However, this only
-		// happens with ill-formed UTF-8.
-		x := make([]byte, 0)
-		x = append(x, rb.out[len(rb.out)-extra:]...)
-		rb.out = rb.out[:end]
-		decomposeToLastBoundary(rb)
-		rb.doFlush()
-		rb.out = append(rb.out, x...)
-		return false
-	}
-	buf := rb.out[p:]
-	rb.out = rb.out[:p]
-	decomposeToLastBoundary(rb)
-	if s := rb.ss.next(info); s == ssStarter {
-		rb.doFlush()
-		rb.ss.first(info)
-	} else if s == ssOverflow {
-		rb.doFlush()
-		rb.insertCGJ()
-		rb.ss = 0
-	}
-	rb.insertUnsafe(inputBytes(buf), 0, info)
-	return true
-}
-
-func appendQuick(rb *reorderBuffer, i int) int {
-	if rb.nsrc == i {
-		return i
-	}
-	end, _ := rb.f.quickSpan(rb.src, i, rb.nsrc, true)
-	rb.out = rb.src.appendSlice(rb.out, i, end)
-	return end
-}
-
-// Append returns f(append(out, b...)).
-// The buffer out must be nil, empty, or equal to f(out).
-func (f Form) Append(out []byte, src ...byte) []byte {
-	return f.doAppend(out, inputBytes(src), len(src))
-}
-
-func (f Form) doAppend(out []byte, src input, n int) []byte {
-	if n == 0 {
-		return out
-	}
-	ft := formTable[f]
-	// Attempt to do a quickSpan first so we can avoid initializing the reorderBuffer.
-	if len(out) == 0 {
-		p, _ := ft.quickSpan(src, 0, n, true)
-		out = src.appendSlice(out, 0, p)
-		if p == n {
-			return out
-		}
-		rb := reorderBuffer{f: *ft, src: src, nsrc: n, out: out, flushF: appendFlush}
-		return doAppendInner(&rb, p)
-	}
-	rb := reorderBuffer{f: *ft, src: src, nsrc: n}
-	return doAppend(&rb, out, 0)
-}
-
-func doAppend(rb *reorderBuffer, out []byte, p int) []byte {
-	rb.setFlusher(out, appendFlush)
-	src, n := rb.src, rb.nsrc
-	doMerge := len(out) > 0
-	if q := src.skipContinuationBytes(p); q > p {
-		// Move leading non-starters to destination.
-		rb.out = src.appendSlice(rb.out, p, q)
-		p = q
-		doMerge = patchTail(rb)
-	}
-	fd := &rb.f
-	if doMerge {
-		var info Properties
-		if p < n {
-			info = fd.info(src, p)
-			if !info.BoundaryBefore() || info.nLeadingNonStarters() > 0 {
-				if p == 0 {
-					decomposeToLastBoundary(rb)
-				}
-				p = decomposeSegment(rb, p, true)
-			}
-		}
-		if info.size == 0 {
-			rb.doFlush()
-			// Append incomplete UTF-8 encoding.
-			return src.appendSlice(rb.out, p, n)
-		}
-		if rb.nrune > 0 {
-			return doAppendInner(rb, p)
-		}
-	}
-	p = appendQuick(rb, p)
-	return doAppendInner(rb, p)
-}
-
-func doAppendInner(rb *reorderBuffer, p int) []byte {
-	for n := rb.nsrc; p < n; {
-		p = decomposeSegment(rb, p, true)
-		p = appendQuick(rb, p)
-	}
-	return rb.out
-}
-
-// AppendString returns f(append(out, []byte(s))).
-// The buffer out must be nil, empty, or equal to f(out).
-func (f Form) AppendString(out []byte, src string) []byte {
-	return f.doAppend(out, inputString(src), len(src))
-}
-
-// QuickSpan returns a boundary n such that b[0:n] == f(b[0:n]).
-// It is not guaranteed to return the largest such n.
-func (f Form) QuickSpan(b []byte) int {
-	n, _ := formTable[f].quickSpan(inputBytes(b), 0, len(b), true)
-	return n
-}
-
-// Span implements transform.SpanningTransformer. It returns a boundary n such
-// that b[0:n] == f(b[0:n]). It is not guaranteed to return the largest such n.
-func (f Form) Span(b []byte, atEOF bool) (n int, err error) {
-	n, ok := formTable[f].quickSpan(inputBytes(b), 0, len(b), atEOF)
-	if n < len(b) {
-		if !ok {
-			err = transform.ErrEndOfSpan
-		} else {
-			err = transform.ErrShortSrc
-		}
-	}
-	return n, err
-}
-
-// SpanString returns a boundary n such that s[0:n] == f(s[0:n]).
-// It is not guaranteed to return the largest such n.
-func (f Form) SpanString(s string, atEOF bool) (n int, err error) {
-	n, ok := formTable[f].quickSpan(inputString(s), 0, len(s), atEOF)
-	if n < len(s) {
-		if !ok {
-			err = transform.ErrEndOfSpan
-		} else {
-			err = transform.ErrShortSrc
-		}
-	}
-	return n, err
-}
-
-// quickSpan returns a boundary n such that src[0:n] == f(src[0:n]) and
-// whether any non-normalized parts were found. If atEOF is false, n will
-// not point past the last segment if this segment might be become
-// non-normalized by appending other runes.
-func (f *formInfo) quickSpan(src input, i, end int, atEOF bool) (n int, ok bool) {
-	var lastCC uint8
-	ss := streamSafe(0)
-	lastSegStart := i
-	for n = end; i < n; {
-		if j := src.skipASCII(i, n); i != j {
-			i = j
-			lastSegStart = i - 1
-			lastCC = 0
-			ss = 0
-			continue
-		}
-		info := f.info(src, i)
-		if info.size == 0 {
-			if atEOF {
-				// include incomplete runes
-				return n, true
-			}
-			return lastSegStart, true
-		}
-		// This block needs to be before the next, because it is possible to
-		// have an overflow for runes that are starters (e.g. with U+FF9E).
-		switch ss.next(info) {
-		case ssStarter:
-			lastSegStart = i
-		case ssOverflow:
-			return lastSegStart, false
-		case ssSuccess:
-			if lastCC > info.ccc {
-				return lastSegStart, false
-			}
-		}
-		if f.composing {
-			if !info.isYesC() {
-				break
-			}
-		} else {
-			if !info.isYesD() {
-				break
-			}
-		}
-		lastCC = info.ccc
-		i += int(info.size)
-	}
-	if i == n {
-		if !atEOF {
-			n = lastSegStart
-		}
-		return n, true
-	}
-	return lastSegStart, false
-}
-
-// QuickSpanString returns a boundary n such that s[0:n] == f(s[0:n]).
-// It is not guaranteed to return the largest such n.
-func (f Form) QuickSpanString(s string) int {
-	n, _ := formTable[f].quickSpan(inputString(s), 0, len(s), true)
-	return n
-}
-
-// FirstBoundary returns the position i of the first boundary in b
-// or -1 if b contains no boundary.
-func (f Form) FirstBoundary(b []byte) int {
-	return f.firstBoundary(inputBytes(b), len(b))
-}
-
-func (f Form) firstBoundary(src input, nsrc int) int {
-	i := src.skipContinuationBytes(0)
-	if i >= nsrc {
-		return -1
-	}
-	fd := formTable[f]
-	ss := streamSafe(0)
-	// We should call ss.first here, but we can't as the first rune is
-	// skipped already. This means FirstBoundary can't really determine
-	// CGJ insertion points correctly. Luckily it doesn't have to.
-	for {
-		info := fd.info(src, i)
-		if info.size == 0 {
-			return -1
-		}
-		if s := ss.next(info); s != ssSuccess {
-			return i
-		}
-		i += int(info.size)
-		if i >= nsrc {
-			if !info.BoundaryAfter() && !ss.isMax() {
-				return -1
-			}
-			return nsrc
-		}
-	}
-}
-
-// FirstBoundaryInString returns the position i of the first boundary in s
-// or -1 if s contains no boundary.
-func (f Form) FirstBoundaryInString(s string) int {
-	return f.firstBoundary(inputString(s), len(s))
-}
-
-// NextBoundary reports the index of the boundary between the first and next
-// segment in b or -1 if atEOF is false and there are not enough bytes to
-// determine this boundary.
-func (f Form) NextBoundary(b []byte, atEOF bool) int {
-	return f.nextBoundary(inputBytes(b), len(b), atEOF)
-}
-
-// NextBoundaryInString reports the index of the boundary between the first and
-// next segment in b or -1 if atEOF is false and there are not enough bytes to
-// determine this boundary.
-func (f Form) NextBoundaryInString(s string, atEOF bool) int {
-	return f.nextBoundary(inputString(s), len(s), atEOF)
-}
-
-func (f Form) nextBoundary(src input, nsrc int, atEOF bool) int {
-	if nsrc == 0 {
-		if atEOF {
-			return 0
-		}
-		return -1
-	}
-	fd := formTable[f]
-	info := fd.info(src, 0)
-	if info.size == 0 {
-		if atEOF {
-			return 1
-		}
-		return -1
-	}
-	ss := streamSafe(0)
-	ss.first(info)
-
-	for i := int(info.size); i < nsrc; i += int(info.size) {
-		info = fd.info(src, i)
-		if info.size == 0 {
-			if atEOF {
-				return i
-			}
-			return -1
-		}
-		// TODO: Using streamSafe to determine the boundary isn't the same as
-		// using BoundaryBefore. Determine which should be used.
-		if s := ss.next(info); s != ssSuccess {
-			return i
-		}
-	}
-	if !atEOF && !info.BoundaryAfter() && !ss.isMax() {
-		return -1
-	}
-	return nsrc
-}
-
-// LastBoundary returns the position i of the last boundary in b
-// or -1 if b contains no boundary.
-func (f Form) LastBoundary(b []byte) int {
-	return lastBoundary(formTable[f], b)
-}
-
-func lastBoundary(fd *formInfo, b []byte) int {
-	i := len(b)
-	info, p := lastRuneStart(fd, b)
-	if p == -1 {
-		return -1
-	}
-	if info.size == 0 { // ends with incomplete rune
-		if p == 0 { // starts with incomplete rune
-			return -1
-		}
-		i = p
-		info, p = lastRuneStart(fd, b[:i])
-		if p == -1 { // incomplete UTF-8 encoding or non-starter bytes without a starter
-			return i
-		}
-	}
-	if p+int(info.size) != i { // trailing non-starter bytes: illegal UTF-8
-		return i
-	}
-	if info.BoundaryAfter() {
-		return i
-	}
-	ss := streamSafe(0)
-	v := ss.backwards(info)
-	for i = p; i >= 0 && v != ssStarter; i = p {
-		info, p = lastRuneStart(fd, b[:i])
-		if v = ss.backwards(info); v == ssOverflow {
-			break
-		}
-		if p+int(info.size) != i {
-			if p == -1 { // no boundary found
-				return -1
-			}
-			return i // boundary after an illegal UTF-8 encoding
-		}
-	}
-	return i
-}
-
-// decomposeSegment scans the first segment in src into rb. It inserts 0x034f
-// (Grapheme Joiner) when it encounters a sequence of more than 30 non-starters
-// and returns the number of bytes consumed from src or iShortDst or iShortSrc.
-func decomposeSegment(rb *reorderBuffer, sp int, atEOF bool) int {
-	// Force one character to be consumed.
-	info := rb.f.info(rb.src, sp)
-	if info.size == 0 {
-		return 0
-	}
-	if s := rb.ss.next(info); s == ssStarter {
-		// TODO: this could be removed if we don't support merging.
-		if rb.nrune > 0 {
-			goto end
-		}
-	} else if s == ssOverflow {
-		rb.insertCGJ()
-		goto end
-	}
-	if err := rb.insertFlush(rb.src, sp, info); err != iSuccess {
-		return int(err)
-	}
-	for {
-		sp += int(info.size)
-		if sp >= rb.nsrc {
-			if !atEOF && !info.BoundaryAfter() {
-				return int(iShortSrc)
-			}
-			break
-		}
-		info = rb.f.info(rb.src, sp)
-		if info.size == 0 {
-			if !atEOF {
-				return int(iShortSrc)
-			}
-			break
-		}
-		if s := rb.ss.next(info); s == ssStarter {
-			break
-		} else if s == ssOverflow {
-			rb.insertCGJ()
-			break
-		}
-		if err := rb.insertFlush(rb.src, sp, info); err != iSuccess {
-			return int(err)
-		}
-	}
-end:
-	if !rb.doFlush() {
-		return int(iShortDst)
-	}
-	return sp
-}
-
-// lastRuneStart returns the runeInfo and position of the last
-// rune in buf or the zero runeInfo and -1 if no rune was found.
-func lastRuneStart(fd *formInfo, buf []byte) (Properties, int) {
-	p := len(buf) - 1
-	for ; p >= 0 && !utf8.RuneStart(buf[p]); p-- {
-	}
-	if p < 0 {
-		return Properties{}, -1
-	}
-	return fd.info(inputBytes(buf), p), p
-}
-
-// decomposeToLastBoundary finds an open segment at the end of the buffer
-// and scans it into rb. Returns the buffer minus the last segment.
-func decomposeToLastBoundary(rb *reorderBuffer) {
-	fd := &rb.f
-	info, i := lastRuneStart(fd, rb.out)
-	if int(info.size) != len(rb.out)-i {
-		// illegal trailing continuation bytes
-		return
-	}
-	if info.BoundaryAfter() {
-		return
-	}
-	var add [maxNonStarters + 1]Properties // stores runeInfo in reverse order
-	padd := 0
-	ss := streamSafe(0)
-	p := len(rb.out)
-	for {
-		add[padd] = info
-		v := ss.backwards(info)
-		if v == ssOverflow {
-			// Note that if we have an overflow, it the string we are appending to
-			// is not correctly normalized. In this case the behavior is undefined.
-			break
-		}
-		padd++
-		p -= int(info.size)
-		if v == ssStarter || p < 0 {
-			break
-		}
-		info, i = lastRuneStart(fd, rb.out[:p])
-		if int(info.size) != p-i {
-			break
-		}
-	}
-	rb.ss = ss
-	// Copy bytes for insertion as we may need to overwrite rb.out.
-	var buf [maxBufferSize * utf8.UTFMax]byte
-	cp := buf[:copy(buf[:], rb.out[p:])]
-	rb.out = rb.out[:p]
-	for padd--; padd >= 0; padd-- {
-		info = add[padd]
-		rb.insertUnsafe(inputBytes(cp), 0, info)
-		cp = cp[info.size:]
-	}
-}
diff --git a/contrib/go/_std_1.19/src/bufio/bufio.go b/contrib/go/_std_1.19/src/bufio/bufio.go
new file mode 100644
index 0000000000..1da8ffa951
--- /dev/null
+++ b/contrib/go/_std_1.19/src/bufio/bufio.go
@@ -0,0 +1,829 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package bufio implements buffered I/O. It wraps an io.Reader or io.Writer
+// object, creating another object (Reader or Writer) that also implements
+// the interface but provides buffering and some help for textual I/O.
+package bufio
+
+import (
+	"bytes"
+	"errors"
+	"io"
+	"strings"
+	"unicode/utf8"
+)
+
+const (
+	defaultBufSize = 4096
+)
+
+var (
+	ErrInvalidUnreadByte = errors.New("bufio: invalid use of UnreadByte")
+	ErrInvalidUnreadRune = errors.New("bufio: invalid use of UnreadRune")
+	ErrBufferFull        = errors.New("bufio: buffer full")
+	ErrNegativeCount     = errors.New("bufio: negative count")
+)
+
+// Buffered input.
+
+// Reader implements buffering for an io.Reader object.
+type Reader struct {
+	buf          []byte
+	rd           io.Reader // reader provided by the client
+	r, w         int       // buf read and write positions
+	err          error
+	lastByte     int // last byte read for UnreadByte; -1 means invalid
+	lastRuneSize int // size of last rune read for UnreadRune; -1 means invalid
+}
+
+const minReadBufferSize = 16
+const maxConsecutiveEmptyReads = 100
+
+// NewReaderSize returns a new Reader whose buffer has at least the specified
+// size. If the argument io.Reader is already a Reader with large enough
+// size, it returns the underlying Reader.
+func NewReaderSize(rd io.Reader, size int) *Reader {
+	// Is it already a Reader?
+	b, ok := rd.(*Reader)
+	if ok && len(b.buf) >= size {
+		return b
+	}
+	if size < minReadBufferSize {
+		size = minReadBufferSize
+	}
+	r := new(Reader)
+	r.reset(make([]byte, size), rd)
+	return r
+}
+
+// NewReader returns a new Reader whose buffer has the default size.
+func NewReader(rd io.Reader) *Reader {
+	return NewReaderSize(rd, defaultBufSize)
+}
+
+// Size returns the size of the underlying buffer in bytes.
+func (b *Reader) Size() int { return len(b.buf) }
+
+// Reset discards any buffered data, resets all state, and switches
+// the buffered reader to read from r.
+// Calling Reset on the zero value of Reader initializes the internal buffer
+// to the default size.
+func (b *Reader) Reset(r io.Reader) {
+	if b.buf == nil {
+		b.buf = make([]byte, defaultBufSize)
+	}
+	b.reset(b.buf, r)
+}
+
+func (b *Reader) reset(buf []byte, r io.Reader) {
+	*b = Reader{
+		buf:          buf,
+		rd:           r,
+		lastByte:     -1,
+		lastRuneSize: -1,
+	}
+}
+
+var errNegativeRead = errors.New("bufio: reader returned negative count from Read")
+
+// fill reads a new chunk into the buffer.
+func (b *Reader) fill() {
+	// Slide existing data to beginning.
+	if b.r > 0 {
+		copy(b.buf, b.buf[b.r:b.w])
+		b.w -= b.r
+		b.r = 0
+	}
+
+	if b.w >= len(b.buf) {
+		panic("bufio: tried to fill full buffer")
+	}
+
+	// Read new data: try a limited number of times.
+	for i := maxConsecutiveEmptyReads; i > 0; i-- {
+		n, err := b.rd.Read(b.buf[b.w:])
+		if n < 0 {
+			panic(errNegativeRead)
+		}
+		b.w += n
+		if err != nil {
+			b.err = err
+			return
+		}
+		if n > 0 {
+			return
+		}
+	}
+	b.err = io.ErrNoProgress
+}
+
+func (b *Reader) readErr() error {
+	err := b.err
+	b.err = nil
+	return err
+}
+
+// Peek returns the next n bytes without advancing the reader. The bytes stop
+// being valid at the next read call. If Peek returns fewer than n bytes, it
+// also returns an error explaining why the read is short. The error is
+// ErrBufferFull if n is larger than b's buffer size.
+//
+// Calling Peek prevents a UnreadByte or UnreadRune call from succeeding
+// until the next read operation.
+func (b *Reader) Peek(n int) ([]byte, error) {
+	if n < 0 {
+		return nil, ErrNegativeCount
+	}
+
+	b.lastByte = -1
+	b.lastRuneSize = -1
+
+	for b.w-b.r < n && b.w-b.r < len(b.buf) && b.err == nil {
+		b.fill() // b.w-b.r < len(b.buf) => buffer is not full
+	}
+
+	if n > len(b.buf) {
+		return b.buf[b.r:b.w], ErrBufferFull
+	}
+
+	// 0 <= n <= len(b.buf)
+	var err error
+	if avail := b.w - b.r; avail < n {
+		// not enough data in buffer
+		n = avail
+		err = b.readErr()
+		if err == nil {
+			err = ErrBufferFull
+		}
+	}
+	return b.buf[b.r : b.r+n], err
+}
+
+// Discard skips the next n bytes, returning the number of bytes discarded.
+//
+// If Discard skips fewer than n bytes, it also returns an error.
+// If 0 <= n <= b.Buffered(), Discard is guaranteed to succeed without
+// reading from the underlying io.Reader.
+func (b *Reader) Discard(n int) (discarded int, err error) {
+	if n < 0 {
+		return 0, ErrNegativeCount
+	}
+	if n == 0 {
+		return
+	}
+
+	b.lastByte = -1
+	b.lastRuneSize = -1
+
+	remain := n
+	for {
+		skip := b.Buffered()
+		if skip == 0 {
+			b.fill()
+			skip = b.Buffered()
+		}
+		if skip > remain {
+			skip = remain
+		}
+		b.r += skip
+		remain -= skip
+		if remain == 0 {
+			return n, nil
+		}
+		if b.err != nil {
+			return n - remain, b.readErr()
+		}
+	}
+}
+
+// Read reads data into p.
+// It returns the number of bytes read into p.
+// The bytes are taken from at most one Read on the underlying Reader,
+// hence n may be less than len(p).
+// To read exactly len(p) bytes, use io.ReadFull(b, p).
+// If the underlying Reader can return a non-zero count with io.EOF,
+// then this Read method can do so as well; see the [io.Reader] docs.
+func (b *Reader) Read(p []byte) (n int, err error) {
+	n = len(p)
+	if n == 0 {
+		if b.Buffered() > 0 {
+			return 0, nil
+		}
+		return 0, b.readErr()
+	}
+	if b.r == b.w {
+		if b.err != nil {
+			return 0, b.readErr()
+		}
+		if len(p) >= len(b.buf) {
+			// Large read, empty buffer.
+			// Read directly into p to avoid copy.
+			n, b.err = b.rd.Read(p)
+			if n < 0 {
+				panic(errNegativeRead)
+			}
+			if n > 0 {
+				b.lastByte = int(p[n-1])
+				b.lastRuneSize = -1
+			}
+			return n, b.readErr()
+		}
+		// One read.
+		// Do not use b.fill, which will loop.
+		b.r = 0
+		b.w = 0
+		n, b.err = b.rd.Read(b.buf)
+		if n < 0 {
+			panic(errNegativeRead)
+		}
+		if n == 0 {
+			return 0, b.readErr()
+		}
+		b.w += n
+	}
+
+	// copy as much as we can
+	// Note: if the slice panics here, it is probably because
+	// the underlying reader returned a bad count. See issue 49795.
+	n = copy(p, b.buf[b.r:b.w])
+	b.r += n
+	b.lastByte = int(b.buf[b.r-1])
+	b.lastRuneSize = -1
+	return n, nil
+}
+
+// ReadByte reads and returns a single byte.
+// If no byte is available, returns an error.
+func (b *Reader) ReadByte() (byte, error) {
+	b.lastRuneSize = -1
+	for b.r == b.w {
+		if b.err != nil {
+			return 0, b.readErr()
+		}
+		b.fill() // buffer is empty
+	}
+	c := b.buf[b.r]
+	b.r++
+	b.lastByte = int(c)
+	return c, nil
+}
+
+// UnreadByte unreads the last byte. Only the most recently read byte can be unread.
+//
+// UnreadByte returns an error if the most recent method called on the
+// Reader was not a read operation. Notably, Peek, Discard, and WriteTo are not
+// considered read operations.
+func (b *Reader) UnreadByte() error {
+	if b.lastByte < 0 || b.r == 0 && b.w > 0 {
+		return ErrInvalidUnreadByte
+	}
+	// b.r > 0 || b.w == 0
+	if b.r > 0 {
+		b.r--
+	} else {
+		// b.r == 0 && b.w == 0
+		b.w = 1
+	}
+	b.buf[b.r] = byte(b.lastByte)
+	b.lastByte = -1
+	b.lastRuneSize = -1
+	return nil
+}
+
+// ReadRune reads a single UTF-8 encoded Unicode character and returns the
+// rune and its size in bytes. If the encoded rune is invalid, it consumes one byte
+// and returns unicode.ReplacementChar (U+FFFD) with a size of 1.
+func (b *Reader) ReadRune() (r rune, size int, err error) {
+	for b.r+utf8.UTFMax > b.w && !utf8.FullRune(b.buf[b.r:b.w]) && b.err == nil && b.w-b.r < len(b.buf) {
+		b.fill() // b.w-b.r < len(buf) => buffer is not full
+	}
+	b.lastRuneSize = -1
+	if b.r == b.w {
+		return 0, 0, b.readErr()
+	}
+	r, size = rune(b.buf[b.r]), 1
+	if r >= utf8.RuneSelf {
+		r, size = utf8.DecodeRune(b.buf[b.r:b.w])
+	}
+	b.r += size
+	b.lastByte = int(b.buf[b.r-1])
+	b.lastRuneSize = size
+	return r, size, nil
+}
+
+// UnreadRune unreads the last rune. If the most recent method called on
+// the Reader was not a ReadRune, UnreadRune returns an error. (In this
+// regard it is stricter than UnreadByte, which will unread the last byte
+// from any read operation.)
+func (b *Reader) UnreadRune() error {
+	if b.lastRuneSize < 0 || b.r < b.lastRuneSize {
+		return ErrInvalidUnreadRune
+	}
+	b.r -= b.lastRuneSize
+	b.lastByte = -1
+	b.lastRuneSize = -1
+	return nil
+}
+
+// Buffered returns the number of bytes that can be read from the current buffer.
+func (b *Reader) Buffered() int { return b.w - b.r }
+
+// ReadSlice reads until the first occurrence of delim in the input,
+// returning a slice pointing at the bytes in the buffer.
+// The bytes stop being valid at the next read.
+// If ReadSlice encounters an error before finding a delimiter,
+// it returns all the data in the buffer and the error itself (often io.EOF).
+// ReadSlice fails with error ErrBufferFull if the buffer fills without a delim.
+// Because the data returned from ReadSlice will be overwritten
+// by the next I/O operation, most clients should use
+// ReadBytes or ReadString instead.
+// ReadSlice returns err != nil if and only if line does not end in delim.
+func (b *Reader) ReadSlice(delim byte) (line []byte, err error) {
+	s := 0 // search start index
+	for {
+		// Search buffer.
+		if i := bytes.IndexByte(b.buf[b.r+s:b.w], delim); i >= 0 {
+			i += s
+			line = b.buf[b.r : b.r+i+1]
+			b.r += i + 1
+			break
+		}
+
+		// Pending error?
+		if b.err != nil {
+			line = b.buf[b.r:b.w]
+			b.r = b.w
+			err = b.readErr()
+			break
+		}
+
+		// Buffer full?
+		if b.Buffered() >= len(b.buf) {
+			b.r = b.w
+			line = b.buf
+			err = ErrBufferFull
+			break
+		}
+
+		s = b.w - b.r // do not rescan area we scanned before
+
+		b.fill() // buffer is not full
+	}
+
+	// Handle last byte, if any.
+	if i := len(line) - 1; i >= 0 {
+		b.lastByte = int(line[i])
+		b.lastRuneSize = -1
+	}
+
+	return
+}
+
+// ReadLine is a low-level line-reading primitive. Most callers should use
+// ReadBytes('\n') or ReadString('\n') instead or use a Scanner.
+//
+// ReadLine tries to return a single line, not including the end-of-line bytes.
+// If the line was too long for the buffer then isPrefix is set and the
+// beginning of the line is returned. The rest of the line will be returned
+// from future calls. isPrefix will be false when returning the last fragment
+// of the line. The returned buffer is only valid until the next call to
+// ReadLine. ReadLine either returns a non-nil line or it returns an error,
+// never both.
+//
+// The text returned from ReadLine does not include the line end ("\r\n" or "\n").
+// No indication or error is given if the input ends without a final line end.
+// Calling UnreadByte after ReadLine will always unread the last byte read
+// (possibly a character belonging to the line end) even if that byte is not
+// part of the line returned by ReadLine.
+func (b *Reader) ReadLine() (line []byte, isPrefix bool, err error) {
+	line, err = b.ReadSlice('\n')
+	if err == ErrBufferFull {
+		// Handle the case where "\r\n" straddles the buffer.
+		if len(line) > 0 && line[len(line)-1] == '\r' {
+			// Put the '\r' back on buf and drop it from line.
+			// Let the next call to ReadLine check for "\r\n".
+			if b.r == 0 {
+				// should be unreachable
+				panic("bufio: tried to rewind past start of buffer")
+			}
+			b.r--
+			line = line[:len(line)-1]
+		}
+		return line, true, nil
+	}
+
+	if len(line) == 0 {
+		if err != nil {
+			line = nil
+		}
+		return
+	}
+	err = nil
+
+	if line[len(line)-1] == '\n' {
+		drop := 1
+		if len(line) > 1 && line[len(line)-2] == '\r' {
+			drop = 2
+		}
+		line = line[:len(line)-drop]
+	}
+	return
+}
+
+// collectFragments reads until the first occurrence of delim in the input. It
+// returns (slice of full buffers, remaining bytes before delim, total number
+// of bytes in the combined first two elements, error).
+// The complete result is equal to
+// `bytes.Join(append(fullBuffers, finalFragment), nil)`, which has a
+// length of `totalLen`. The result is structured in this way to allow callers
+// to minimize allocations and copies.
+func (b *Reader) collectFragments(delim byte) (fullBuffers [][]byte, finalFragment []byte, totalLen int, err error) {
+	var frag []byte
+	// Use ReadSlice to look for delim, accumulating full buffers.
+	for {
+		var e error
+		frag, e = b.ReadSlice(delim)
+		if e == nil { // got final fragment
+			break
+		}
+		if e != ErrBufferFull { // unexpected error
+			err = e
+			break
+		}
+
+		// Make a copy of the buffer.
+		buf := make([]byte, len(frag))
+		copy(buf, frag)
+		fullBuffers = append(fullBuffers, buf)
+		totalLen += len(buf)
+	}
+
+	totalLen += len(frag)
+	return fullBuffers, frag, totalLen, err
+}
+
+// ReadBytes reads until the first occurrence of delim in the input,
+// returning a slice containing the data up to and including the delimiter.
+// If ReadBytes encounters an error before finding a delimiter,
+// it returns the data read before the error and the error itself (often io.EOF).
+// ReadBytes returns err != nil if and only if the returned data does not end in
+// delim.
+// For simple uses, a Scanner may be more convenient.
+func (b *Reader) ReadBytes(delim byte) ([]byte, error) {
+	full, frag, n, err := b.collectFragments(delim)
+	// Allocate new buffer to hold the full pieces and the fragment.
+	buf := make([]byte, n)
+	n = 0
+	// Copy full pieces and fragment in.
+	for i := range full {
+		n += copy(buf[n:], full[i])
+	}
+	copy(buf[n:], frag)
+	return buf, err
+}
+
+// ReadString reads until the first occurrence of delim in the input,
+// returning a string containing the data up to and including the delimiter.
+// If ReadString encounters an error before finding a delimiter,
+// it returns the data read before the error and the error itself (often io.EOF).
+// ReadString returns err != nil if and only if the returned data does not end in
+// delim.
+// For simple uses, a Scanner may be more convenient.
+func (b *Reader) ReadString(delim byte) (string, error) {
+	full, frag, n, err := b.collectFragments(delim)
+	// Allocate new buffer to hold the full pieces and the fragment.
+	var buf strings.Builder
+	buf.Grow(n)
+	// Copy full pieces and fragment in.
+	for _, fb := range full {
+		buf.Write(fb)
+	}
+	buf.Write(frag)
+	return buf.String(), err
+}
+
+// WriteTo implements io.WriterTo.
+// This may make multiple calls to the Read method of the underlying Reader.
+// If the underlying reader supports the WriteTo method,
+// this calls the underlying WriteTo without buffering.
+func (b *Reader) WriteTo(w io.Writer) (n int64, err error) {
+	b.lastByte = -1
+	b.lastRuneSize = -1
+
+	n, err = b.writeBuf(w)
+	if err != nil {
+		return
+	}
+
+	if r, ok := b.rd.(io.WriterTo); ok {
+		m, err := r.WriteTo(w)
+		n += m
+		return n, err
+	}
+
+	if w, ok := w.(io.ReaderFrom); ok {
+		m, err := w.ReadFrom(b.rd)
+		n += m
+		return n, err
+	}
+
+	if b.w-b.r < len(b.buf) {
+		b.fill() // buffer not full
+	}
+
+	for b.r < b.w {
+		// b.r < b.w => buffer is not empty
+		m, err := b.writeBuf(w)
+		n += m
+		if err != nil {
+			return n, err
+		}
+		b.fill() // buffer is empty
+	}
+
+	if b.err == io.EOF {
+		b.err = nil
+	}
+
+	return n, b.readErr()
+}
+
+var errNegativeWrite = errors.New("bufio: writer returned negative count from Write")
+
+// writeBuf writes the Reader's buffer to the writer.
+func (b *Reader) writeBuf(w io.Writer) (int64, error) {
+	n, err := w.Write(b.buf[b.r:b.w])
+	if n < 0 {
+		panic(errNegativeWrite)
+	}
+	b.r += n
+	return int64(n), err
+}
+
+// buffered output
+
+// Writer implements buffering for an io.Writer object.
+// If an error occurs writing to a Writer, no more data will be
+// accepted and all subsequent writes, and Flush, will return the error.
+// After all data has been written, the client should call the
+// Flush method to guarantee all data has been forwarded to
+// the underlying io.Writer.
+type Writer struct {
+	err error
+	buf []byte
+	n   int
+	wr  io.Writer
+}
+
+// NewWriterSize returns a new Writer whose buffer has at least the specified
+// size. If the argument io.Writer is already a Writer with large enough
+// size, it returns the underlying Writer.
+func NewWriterSize(w io.Writer, size int) *Writer {
+	// Is it already a Writer?
+	b, ok := w.(*Writer)
+	if ok && len(b.buf) >= size {
+		return b
+	}
+	if size <= 0 {
+		size = defaultBufSize
+	}
+	return &Writer{
+		buf: make([]byte, size),
+		wr:  w,
+	}
+}
+
+// NewWriter returns a new Writer whose buffer has the default size.
+// If the argument io.Writer is already a Writer with large enough buffer size,
+// it returns the underlying Writer.
+func NewWriter(w io.Writer) *Writer {
+	return NewWriterSize(w, defaultBufSize)
+}
+
+// Size returns the size of the underlying buffer in bytes.
+func (b *Writer) Size() int { return len(b.buf) }
+
+// Reset discards any unflushed buffered data, clears any error, and
+// resets b to write its output to w.
+// Calling Reset on the zero value of Writer initializes the internal buffer
+// to the default size.
+func (b *Writer) Reset(w io.Writer) {
+	if b.buf == nil {
+		b.buf = make([]byte, defaultBufSize)
+	}
+	b.err = nil
+	b.n = 0
+	b.wr = w
+}
+
+// Flush writes any buffered data to the underlying io.Writer.
+func (b *Writer) Flush() error {
+	if b.err != nil {
+		return b.err
+	}
+	if b.n == 0 {
+		return nil
+	}
+	n, err := b.wr.Write(b.buf[0:b.n])
+	if n < b.n && err == nil {
+		err = io.ErrShortWrite
+	}
+	if err != nil {
+		if n > 0 && n < b.n {
+			copy(b.buf[0:b.n-n], b.buf[n:b.n])
+		}
+		b.n -= n
+		b.err = err
+		return err
+	}
+	b.n = 0
+	return nil
+}
+
+// Available returns how many bytes are unused in the buffer.
+func (b *Writer) Available() int { return len(b.buf) - b.n }
+
+// AvailableBuffer returns an empty buffer with b.Available() capacity.
+// This buffer is intended to be appended to and
+// passed to an immediately succeeding Write call.
+// The buffer is only valid until the next write operation on b.
+func (b *Writer) AvailableBuffer() []byte {
+	return b.buf[b.n:][:0]
+}
+
+// Buffered returns the number of bytes that have been written into the current buffer.
+func (b *Writer) Buffered() int { return b.n }
+
+// Write writes the contents of p into the buffer.
+// It returns the number of bytes written.
+// If nn < len(p), it also returns an error explaining
+// why the write is short.
+func (b *Writer) Write(p []byte) (nn int, err error) {
+	for len(p) > b.Available() && b.err == nil {
+		var n int
+		if b.Buffered() == 0 {
+			// Large write, empty buffer.
+			// Write directly from p to avoid copy.
+			n, b.err = b.wr.Write(p)
+		} else {
+			n = copy(b.buf[b.n:], p)
+			b.n += n
+			b.Flush()
+		}
+		nn += n
+		p = p[n:]
+	}
+	if b.err != nil {
+		return nn, b.err
+	}
+	n := copy(b.buf[b.n:], p)
+	b.n += n
+	nn += n
+	return nn, nil
+}
+
+// WriteByte writes a single byte.
+func (b *Writer) WriteByte(c byte) error {
+	if b.err != nil {
+		return b.err
+	}
+	if b.Available() <= 0 && b.Flush() != nil {
+		return b.err
+	}
+	b.buf[b.n] = c
+	b.n++
+	return nil
+}
+
+// WriteRune writes a single Unicode code point, returning
+// the number of bytes written and any error.
+func (b *Writer) WriteRune(r rune) (size int, err error) {
+	// Compare as uint32 to correctly handle negative runes.
+	if uint32(r) < utf8.RuneSelf {
+		err = b.WriteByte(byte(r))
+		if err != nil {
+			return 0, err
+		}
+		return 1, nil
+	}
+	if b.err != nil {
+		return 0, b.err
+	}
+	n := b.Available()
+	if n < utf8.UTFMax {
+		if b.Flush(); b.err != nil {
+			return 0, b.err
+		}
+		n = b.Available()
+		if n < utf8.UTFMax {
+			// Can only happen if buffer is silly small.
+			return b.WriteString(string(r))
+		}
+	}
+	size = utf8.EncodeRune(b.buf[b.n:], r)
+	b.n += size
+	return size, nil
+}
+
+// WriteString writes a string.
+// It returns the number of bytes written.
+// If the count is less than len(s), it also returns an error explaining
+// why the write is short.
+func (b *Writer) WriteString(s string) (int, error) {
+	var sw io.StringWriter
+	tryStringWriter := true
+
+	nn := 0
+	for len(s) > b.Available() && b.err == nil {
+		var n int
+		if b.Buffered() == 0 && sw == nil && tryStringWriter {
+			// Check at most once whether b.wr is a StringWriter.
+			sw, tryStringWriter = b.wr.(io.StringWriter)
+		}
+		if b.Buffered() == 0 && tryStringWriter {
+			// Large write, empty buffer, and the underlying writer supports
+			// WriteString: forward the write to the underlying StringWriter.
+			// This avoids an extra copy.
+			n, b.err = sw.WriteString(s)
+		} else {
+			n = copy(b.buf[b.n:], s)
+			b.n += n
+			b.Flush()
+		}
+		nn += n
+		s = s[n:]
+	}
+	if b.err != nil {
+		return nn, b.err
+	}
+	n := copy(b.buf[b.n:], s)
+	b.n += n
+	nn += n
+	return nn, nil
+}
+
+// ReadFrom implements io.ReaderFrom. If the underlying writer
+// supports the ReadFrom method, this calls the underlying ReadFrom.
+// If there is buffered data and an underlying ReadFrom, this fills
+// the buffer and writes it before calling ReadFrom.
+func (b *Writer) ReadFrom(r io.Reader) (n int64, err error) {
+	if b.err != nil {
+		return 0, b.err
+	}
+	readerFrom, readerFromOK := b.wr.(io.ReaderFrom)
+	var m int
+	for {
+		if b.Available() == 0 {
+			if err1 := b.Flush(); err1 != nil {
+				return n, err1
+			}
+		}
+		if readerFromOK && b.Buffered() == 0 {
+			nn, err := readerFrom.ReadFrom(r)
+			b.err = err
+			n += nn
+			return n, err
+		}
+		nr := 0
+		for nr < maxConsecutiveEmptyReads {
+			m, err = r.Read(b.buf[b.n:])
+			if m != 0 || err != nil {
+				break
+			}
+			nr++
+		}
+		if nr == maxConsecutiveEmptyReads {
+			return n, io.ErrNoProgress
+		}
+		b.n += m
+		n += int64(m)
+		if err != nil {
+			break
+		}
+	}
+	if err == io.EOF {
+		// If we filled the buffer exactly, flush preemptively.
+		if b.Available() == 0 {
+			err = b.Flush()
+		} else {
+			err = nil
+		}
+	}
+	return n, err
+}
+
+// buffered input and output
+
+// ReadWriter stores pointers to a Reader and a Writer.
+// It implements io.ReadWriter.
+type ReadWriter struct {
+	*Reader
+	*Writer
+}
+
+// NewReadWriter allocates a new ReadWriter that dispatches to r and w.
+func NewReadWriter(r *Reader, w *Writer) *ReadWriter {
+	return &ReadWriter{r, w}
+}
diff --git a/contrib/go/_std_1.19/src/bufio/scan.go b/contrib/go/_std_1.19/src/bufio/scan.go
new file mode 100644
index 0000000000..e247cbcf32
--- /dev/null
+++ b/contrib/go/_std_1.19/src/bufio/scan.go
@@ -0,0 +1,419 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bufio
+
+import (
+	"bytes"
+	"errors"
+	"io"
+	"unicode/utf8"
+)
+
+// Scanner provides a convenient interface for reading data such as
+// a file of newline-delimited lines of text. Successive calls to
+// the Scan method will step through the 'tokens' of a file, skipping
+// the bytes between the tokens. The specification of a token is
+// defined by a split function of type SplitFunc; the default split
+// function breaks the input into lines with line termination stripped. Split
+// functions are defined in this package for scanning a file into
+// lines, bytes, UTF-8-encoded runes, and space-delimited words. The
+// client may instead provide a custom split function.
+//
+// Scanning stops unrecoverably at EOF, the first I/O error, or a token too
+// large to fit in the buffer. When a scan stops, the reader may have
+// advanced arbitrarily far past the last token. Programs that need more
+// control over error handling or large tokens, or must run sequential scans
+// on a reader, should use bufio.Reader instead.
+type Scanner struct {
+	r            io.Reader // The reader provided by the client.
+	split        SplitFunc // The function to split the tokens.
+	maxTokenSize int       // Maximum size of a token; modified by tests.
+	token        []byte    // Last token returned by split.
+	buf          []byte    // Buffer used as argument to split.
+	start        int       // First non-processed byte in buf.
+	end          int       // End of data in buf.
+	err          error     // Sticky error.
+	empties      int       // Count of successive empty tokens.
+	scanCalled   bool      // Scan has been called; buffer is in use.
+	done         bool      // Scan has finished.
+}
+
+// SplitFunc is the signature of the split function used to tokenize the
+// input. The arguments are an initial substring of the remaining unprocessed
+// data and a flag, atEOF, that reports whether the Reader has no more data
+// to give. The return values are the number of bytes to advance the input
+// and the next token to return to the user, if any, plus an error, if any.
+//
+// Scanning stops if the function returns an error, in which case some of
+// the input may be discarded. If that error is ErrFinalToken, scanning
+// stops with no error.
+//
+// Otherwise, the Scanner advances the input. If the token is not nil,
+// the Scanner returns it to the user. If the token is nil, the
+// Scanner reads more data and continues scanning; if there is no more
+// data--if atEOF was true--the Scanner returns. If the data does not
+// yet hold a complete token, for instance if it has no newline while
+// scanning lines, a SplitFunc can return (0, nil, nil) to signal the
+// Scanner to read more data into the slice and try again with a
+// longer slice starting at the same point in the input.
+//
+// The function is never called with an empty data slice unless atEOF
+// is true. If atEOF is true, however, data may be non-empty and,
+// as always, holds unprocessed text.
+type SplitFunc func(data []byte, atEOF bool) (advance int, token []byte, err error)
+
+// Errors returned by Scanner.
+var (
+	ErrTooLong         = errors.New("bufio.Scanner: token too long")
+	ErrNegativeAdvance = errors.New("bufio.Scanner: SplitFunc returns negative advance count")
+	ErrAdvanceTooFar   = errors.New("bufio.Scanner: SplitFunc returns advance count beyond input")
+	ErrBadReadCount    = errors.New("bufio.Scanner: Read returned impossible count")
+)
+
+const (
+	// MaxScanTokenSize is the maximum size used to buffer a token
+	// unless the user provides an explicit buffer with Scanner.Buffer.
+	// The actual maximum token size may be smaller as the buffer
+	// may need to include, for instance, a newline.
+	MaxScanTokenSize = 64 * 1024
+
+	startBufSize = 4096 // Size of initial allocation for buffer.
+)
+
+// NewScanner returns a new Scanner to read from r.
+// The split function defaults to ScanLines.
+func NewScanner(r io.Reader) *Scanner {
+	return &Scanner{
+		r:            r,
+		split:        ScanLines,
+		maxTokenSize: MaxScanTokenSize,
+	}
+}
+
+// Err returns the first non-EOF error that was encountered by the Scanner.
+func (s *Scanner) Err() error {
+	if s.err == io.EOF {
+		return nil
+	}
+	return s.err
+}
+
+// Bytes returns the most recent token generated by a call to Scan.
+// The underlying array may point to data that will be overwritten
+// by a subsequent call to Scan. It does no allocation.
+func (s *Scanner) Bytes() []byte {
+	return s.token
+}
+
+// Text returns the most recent token generated by a call to Scan
+// as a newly allocated string holding its bytes.
+func (s *Scanner) Text() string {
+	return string(s.token)
+}
+
+// ErrFinalToken is a special sentinel error value. It is intended to be
+// returned by a Split function to indicate that the token being delivered
+// with the error is the last token and scanning should stop after this one.
+// After ErrFinalToken is received by Scan, scanning stops with no error.
+// The value is useful to stop processing early or when it is necessary to
+// deliver a final empty token. One could achieve the same behavior
+// with a custom error value but providing one here is tidier.
+// See the emptyFinalToken example for a use of this value.
+var ErrFinalToken = errors.New("final token")
+
+// Scan advances the Scanner to the next token, which will then be
+// available through the Bytes or Text method. It returns false when the
+// scan stops, either by reaching the end of the input or an error.
+// After Scan returns false, the Err method will return any error that
+// occurred during scanning, except that if it was io.EOF, Err
+// will return nil.
+// Scan panics if the split function returns too many empty
+// tokens without advancing the input. This is a common error mode for
+// scanners.
+func (s *Scanner) Scan() bool {
+	if s.done {
+		return false
+	}
+	s.scanCalled = true
+	// Loop until we have a token.
+	for {
+		// See if we can get a token with what we already have.
+		// If we've run out of data but have an error, give the split function
+		// a chance to recover any remaining, possibly empty token.
+		if s.end > s.start || s.err != nil {
+			advance, token, err := s.split(s.buf[s.start:s.end], s.err != nil)
+			if err != nil {
+				if err == ErrFinalToken {
+					s.token = token
+					s.done = true
+					return true
+				}
+				s.setErr(err)
+				return false
+			}
+			if !s.advance(advance) {
+				return false
+			}
+			s.token = token
+			if token != nil {
+				if s.err == nil || advance > 0 {
+					s.empties = 0
+				} else {
+					// Returning tokens not advancing input at EOF.
+					s.empties++
+					if s.empties > maxConsecutiveEmptyReads {
+						panic("bufio.Scan: too many empty tokens without progressing")
+					}
+				}
+				return true
+			}
+		}
+		// We cannot generate a token with what we are holding.
+		// If we've already hit EOF or an I/O error, we are done.
+		if s.err != nil {
+			// Shut it down.
+			s.start = 0
+			s.end = 0
+			return false
+		}
+		// Must read more data.
+		// First, shift data to beginning of buffer if there's lots of empty space
+		// or space is needed.
+		if s.start > 0 && (s.end == len(s.buf) || s.start > len(s.buf)/2) {
+			copy(s.buf, s.buf[s.start:s.end])
+			s.end -= s.start
+			s.start = 0
+		}
+		// Is the buffer full? If so, resize.
+		if s.end == len(s.buf) {
+			// Guarantee no overflow in the multiplication below.
+			const maxInt = int(^uint(0) >> 1)
+			if len(s.buf) >= s.maxTokenSize || len(s.buf) > maxInt/2 {
+				s.setErr(ErrTooLong)
+				return false
+			}
+			newSize := len(s.buf) * 2
+			if newSize == 0 {
+				newSize = startBufSize
+			}
+			if newSize > s.maxTokenSize {
+				newSize = s.maxTokenSize
+			}
+			newBuf := make([]byte, newSize)
+			copy(newBuf, s.buf[s.start:s.end])
+			s.buf = newBuf
+			s.end -= s.start
+			s.start = 0
+		}
+		// Finally we can read some input. Make sure we don't get stuck with
+		// a misbehaving Reader. Officially we don't need to do this, but let's
+		// be extra careful: Scanner is for safe, simple jobs.
+		for loop := 0; ; {
+			n, err := s.r.Read(s.buf[s.end:len(s.buf)])
+			if n < 0 || len(s.buf)-s.end < n {
+				s.setErr(ErrBadReadCount)
+				break
+			}
+			s.end += n
+			if err != nil {
+				s.setErr(err)
+				break
+			}
+			if n > 0 {
+				s.empties = 0
+				break
+			}
+			loop++
+			if loop > maxConsecutiveEmptyReads {
+				s.setErr(io.ErrNoProgress)
+				break
+			}
+		}
+	}
+}
+
+// advance consumes n bytes of the buffer. It reports whether the advance was legal.
+func (s *Scanner) advance(n int) bool {
+	if n < 0 {
+		s.setErr(ErrNegativeAdvance)
+		return false
+	}
+	if n > s.end-s.start {
+		s.setErr(ErrAdvanceTooFar)
+		return false
+	}
+	s.start += n
+	return true
+}
+
+// setErr records the first error encountered.
+func (s *Scanner) setErr(err error) {
+	if s.err == nil || s.err == io.EOF {
+		s.err = err
+	}
+}
+
+// Buffer sets the initial buffer to use when scanning and the maximum
+// size of buffer that may be allocated during scanning. The maximum
+// token size is the larger of max and cap(buf). If max <= cap(buf),
+// Scan will use this buffer only and do no allocation.
+//
+// By default, Scan uses an internal buffer and sets the
+// maximum token size to MaxScanTokenSize.
+//
+// Buffer panics if it is called after scanning has started.
+func (s *Scanner) Buffer(buf []byte, max int) {
+	if s.scanCalled {
+		panic("Buffer called after Scan")
+	}
+	s.buf = buf[0:cap(buf)]
+	s.maxTokenSize = max
+}
+
+// Split sets the split function for the Scanner.
+// The default split function is ScanLines.
+//
+// Split panics if it is called after scanning has started.
+func (s *Scanner) Split(split SplitFunc) {
+	if s.scanCalled {
+		panic("Split called after Scan")
+	}
+	s.split = split
+}
+
+// Split functions
+
+// ScanBytes is a split function for a Scanner that returns each byte as a token.
+func ScanBytes(data []byte, atEOF bool) (advance int, token []byte, err error) {
+	if atEOF && len(data) == 0 {
+		return 0, nil, nil
+	}
+	return 1, data[0:1], nil
+}
+
+var errorRune = []byte(string(utf8.RuneError))
+
+// ScanRunes is a split function for a Scanner that returns each
+// UTF-8-encoded rune as a token. The sequence of runes returned is
+// equivalent to that from a range loop over the input as a string, which
+// means that erroneous UTF-8 encodings translate to U+FFFD = "\xef\xbf\xbd".
+// Because of the Scan interface, this makes it impossible for the client to
+// distinguish correctly encoded replacement runes from encoding errors.
+func ScanRunes(data []byte, atEOF bool) (advance int, token []byte, err error) {
+	if atEOF && len(data) == 0 {
+		return 0, nil, nil
+	}
+
+	// Fast path 1: ASCII.
+	if data[0] < utf8.RuneSelf {
+		return 1, data[0:1], nil
+	}
+
+	// Fast path 2: Correct UTF-8 decode without error.
+	_, width := utf8.DecodeRune(data)
+	if width > 1 {
+		// It's a valid encoding. Width cannot be one for a correctly encoded
+		// non-ASCII rune.
+		return width, data[0:width], nil
+	}
+
+	// We know it's an error: we have width==1 and implicitly r==utf8.RuneError.
+	// Is the error because there wasn't a full rune to be decoded?
+	// FullRune distinguishes correctly between erroneous and incomplete encodings.
+	if !atEOF && !utf8.FullRune(data) {
+		// Incomplete; get more bytes.
+		return 0, nil, nil
+	}
+
+	// We have a real UTF-8 encoding error. Return a properly encoded error rune
+	// but advance only one byte. This matches the behavior of a range loop over
+	// an incorrectly encoded string.
+	return 1, errorRune, nil
+}
+
+// dropCR drops a terminal \r from the data.
+func dropCR(data []byte) []byte {
+	if len(data) > 0 && data[len(data)-1] == '\r' {
+		return data[0 : len(data)-1]
+	}
+	return data
+}
+
+// ScanLines is a split function for a Scanner that returns each line of
+// text, stripped of any trailing end-of-line marker. The returned line may
+// be empty. The end-of-line marker is one optional carriage return followed
+// by one mandatory newline. In regular expression notation, it is `\r?\n`.
+// The last non-empty line of input will be returned even if it has no
+// newline.
+func ScanLines(data []byte, atEOF bool) (advance int, token []byte, err error) {
+	if atEOF && len(data) == 0 {
+		return 0, nil, nil
+	}
+	if i := bytes.IndexByte(data, '\n'); i >= 0 {
+		// We have a full newline-terminated line.
+		return i + 1, dropCR(data[0:i]), nil
+	}
+	// If we're at EOF, we have a final, non-terminated line. Return it.
+	if atEOF {
+		return len(data), dropCR(data), nil
+	}
+	// Request more data.
+	return 0, nil, nil
+}
+
+// isSpace reports whether the character is a Unicode white space character.
+// We avoid dependency on the unicode package, but check validity of the implementation
+// in the tests.
+func isSpace(r rune) bool {
+	if r <= '\u00FF' {
+		// Obvious ASCII ones: \t through \r plus space. Plus two Latin-1 oddballs.
+		switch r {
+		case ' ', '\t', '\n', '\v', '\f', '\r':
+			return true
+		case '\u0085', '\u00A0':
+			return true
+		}
+		return false
+	}
+	// High-valued ones.
+	if '\u2000' <= r && r <= '\u200a' {
+		return true
+	}
+	switch r {
+	case '\u1680', '\u2028', '\u2029', '\u202f', '\u205f', '\u3000':
+		return true
+	}
+	return false
+}
+
+// ScanWords is a split function for a Scanner that returns each
+// space-separated word of text, with surrounding spaces deleted. It will
+// never return an empty string. The definition of space is set by
+// unicode.IsSpace.
+func ScanWords(data []byte, atEOF bool) (advance int, token []byte, err error) {
+	// Skip leading spaces.
+	start := 0
+	for width := 0; start < len(data); start += width {
+		var r rune
+		r, width = utf8.DecodeRune(data[start:])
+		if !isSpace(r) {
+			break
+		}
+	}
+	// Scan until space, marking end of word.
+	for width, i := 0, start; i < len(data); i += width {
+		var r rune
+		r, width = utf8.DecodeRune(data[i:])
+		if isSpace(r) {
+			return i + width, data[start:i], nil
+		}
+	}
+	// If we're at EOF, we have a final, non-empty, non-terminated word. Return it.
+	if atEOF && len(data) > start {
+		return len(data), data[start:], nil
+	}
+	// Request more data.
+	return start, nil, nil
+}
diff --git a/contrib/go/_std_1.19/src/bytes/buffer.go b/contrib/go/_std_1.19/src/bytes/buffer.go
new file mode 100644
index 0000000000..0bacbda164
--- /dev/null
+++ b/contrib/go/_std_1.19/src/bytes/buffer.go
@@ -0,0 +1,474 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bytes
+
+// Simple byte buffer for marshaling data.
+
+import (
+	"errors"
+	"io"
+	"unicode/utf8"
+)
+
+// smallBufferSize is an initial allocation minimal capacity.
+const smallBufferSize = 64
+
+// A Buffer is a variable-sized buffer of bytes with Read and Write methods.
+// The zero value for Buffer is an empty buffer ready to use.
+type Buffer struct {
+	buf      []byte // contents are the bytes buf[off : len(buf)]
+	off      int    // read at &buf[off], write at &buf[len(buf)]
+	lastRead readOp // last read operation, so that Unread* can work correctly.
+}
+
+// The readOp constants describe the last action performed on
+// the buffer, so that UnreadRune and UnreadByte can check for
+// invalid usage. opReadRuneX constants are chosen such that
+// converted to int they correspond to the rune size that was read.
+type readOp int8
+
+// Don't use iota for these, as the values need to correspond with the
+// names and comments, which is easier to see when being explicit.
+const (
+	opRead      readOp = -1 // Any other read operation.
+	opInvalid   readOp = 0  // Non-read operation.
+	opReadRune1 readOp = 1  // Read rune of size 1.
+	opReadRune2 readOp = 2  // Read rune of size 2.
+	opReadRune3 readOp = 3  // Read rune of size 3.
+	opReadRune4 readOp = 4  // Read rune of size 4.
+)
+
+// ErrTooLarge is passed to panic if memory cannot be allocated to store data in a buffer.
+var ErrTooLarge = errors.New("bytes.Buffer: too large")
+var errNegativeRead = errors.New("bytes.Buffer: reader returned negative count from Read")
+
+const maxInt = int(^uint(0) >> 1)
+
+// Bytes returns a slice of length b.Len() holding the unread portion of the buffer.
+// The slice is valid for use only until the next buffer modification (that is,
+// only until the next call to a method like Read, Write, Reset, or Truncate).
+// The slice aliases the buffer content at least until the next buffer modification,
+// so immediate changes to the slice will affect the result of future reads.
+func (b *Buffer) Bytes() []byte { return b.buf[b.off:] }
+
+// String returns the contents of the unread portion of the buffer
+// as a string. If the Buffer is a nil pointer, it returns "<nil>".
+//
+// To build strings more efficiently, see the strings.Builder type.
+func (b *Buffer) String() string {
+	if b == nil {
+		// Special case, useful in debugging.
+		return "<nil>"
+	}
+	return string(b.buf[b.off:])
+}
+
+// empty reports whether the unread portion of the buffer is empty.
+func (b *Buffer) empty() bool { return len(b.buf) <= b.off }
+
+// Len returns the number of bytes of the unread portion of the buffer;
+// b.Len() == len(b.Bytes()).
+func (b *Buffer) Len() int { return len(b.buf) - b.off }
+
+// Cap returns the capacity of the buffer's underlying byte slice, that is, the
+// total space allocated for the buffer's data.
+func (b *Buffer) Cap() int { return cap(b.buf) }
+
+// Truncate discards all but the first n unread bytes from the buffer
+// but continues to use the same allocated storage.
+// It panics if n is negative or greater than the length of the buffer.
+func (b *Buffer) Truncate(n int) {
+	if n == 0 {
+		b.Reset()
+		return
+	}
+	b.lastRead = opInvalid
+	if n < 0 || n > b.Len() {
+		panic("bytes.Buffer: truncation out of range")
+	}
+	b.buf = b.buf[:b.off+n]
+}
+
+// Reset resets the buffer to be empty,
+// but it retains the underlying storage for use by future writes.
+// Reset is the same as Truncate(0).
+func (b *Buffer) Reset() {
+	b.buf = b.buf[:0]
+	b.off = 0
+	b.lastRead = opInvalid
+}
+
+// tryGrowByReslice is a inlineable version of grow for the fast-case where the
+// internal buffer only needs to be resliced.
+// It returns the index where bytes should be written and whether it succeeded.
+func (b *Buffer) tryGrowByReslice(n int) (int, bool) {
+	if l := len(b.buf); n <= cap(b.buf)-l {
+		b.buf = b.buf[:l+n]
+		return l, true
+	}
+	return 0, false
+}
+
+// grow grows the buffer to guarantee space for n more bytes.
+// It returns the index where bytes should be written.
+// If the buffer can't grow it will panic with ErrTooLarge.
+func (b *Buffer) grow(n int) int {
+	m := b.Len()
+	// If buffer is empty, reset to recover space.
+	if m == 0 && b.off != 0 {
+		b.Reset()
+	}
+	// Try to grow by means of a reslice.
+	if i, ok := b.tryGrowByReslice(n); ok {
+		return i
+	}
+	if b.buf == nil && n <= smallBufferSize {
+		b.buf = make([]byte, n, smallBufferSize)
+		return 0
+	}
+	c := cap(b.buf)
+	if n <= c/2-m {
+		// We can slide things down instead of allocating a new
+		// slice. We only need m+n <= c to slide, but
+		// we instead let capacity get twice as large so we
+		// don't spend all our time copying.
+		copy(b.buf, b.buf[b.off:])
+	} else if c > maxInt-c-n {
+		panic(ErrTooLarge)
+	} else {
+		// Add b.off to account for b.buf[:b.off] being sliced off the front.
+		b.buf = growSlice(b.buf[b.off:], b.off+n)
+	}
+	// Restore b.off and len(b.buf).
+	b.off = 0
+	b.buf = b.buf[:m+n]
+	return m
+}
+
+// Grow grows the buffer's capacity, if necessary, to guarantee space for
+// another n bytes. After Grow(n), at least n bytes can be written to the
+// buffer without another allocation.
+// If n is negative, Grow will panic.
+// If the buffer can't grow it will panic with ErrTooLarge.
+func (b *Buffer) Grow(n int) {
+	if n < 0 {
+		panic("bytes.Buffer.Grow: negative count")
+	}
+	m := b.grow(n)
+	b.buf = b.buf[:m]
+}
+
+// Write appends the contents of p to the buffer, growing the buffer as
+// needed. The return value n is the length of p; err is always nil. If the
+// buffer becomes too large, Write will panic with ErrTooLarge.
+func (b *Buffer) Write(p []byte) (n int, err error) {
+	b.lastRead = opInvalid
+	m, ok := b.tryGrowByReslice(len(p))
+	if !ok {
+		m = b.grow(len(p))
+	}
+	return copy(b.buf[m:], p), nil
+}
+
+// WriteString appends the contents of s to the buffer, growing the buffer as
+// needed. The return value n is the length of s; err is always nil. If the
+// buffer becomes too large, WriteString will panic with ErrTooLarge.
+func (b *Buffer) WriteString(s string) (n int, err error) {
+	b.lastRead = opInvalid
+	m, ok := b.tryGrowByReslice(len(s))
+	if !ok {
+		m = b.grow(len(s))
+	}
+	return copy(b.buf[m:], s), nil
+}
+
+// MinRead is the minimum slice size passed to a Read call by
+// Buffer.ReadFrom. As long as the Buffer has at least MinRead bytes beyond
+// what is required to hold the contents of r, ReadFrom will not grow the
+// underlying buffer.
+const MinRead = 512
+
+// ReadFrom reads data from r until EOF and appends it to the buffer, growing
+// the buffer as needed. The return value n is the number of bytes read. Any
+// error except io.EOF encountered during the read is also returned. If the
+// buffer becomes too large, ReadFrom will panic with ErrTooLarge.
+func (b *Buffer) ReadFrom(r io.Reader) (n int64, err error) {
+	b.lastRead = opInvalid
+	for {
+		i := b.grow(MinRead)
+		b.buf = b.buf[:i]
+		m, e := r.Read(b.buf[i:cap(b.buf)])
+		if m < 0 {
+			panic(errNegativeRead)
+		}
+
+		b.buf = b.buf[:i+m]
+		n += int64(m)
+		if e == io.EOF {
+			return n, nil // e is EOF, so return nil explicitly
+		}
+		if e != nil {
+			return n, e
+		}
+	}
+}
+
+// growSlice grows b by n, preserving the original content of b.
+// If the allocation fails, it panics with ErrTooLarge.
+func growSlice(b []byte, n int) []byte {
+	defer func() {
+		if recover() != nil {
+			panic(ErrTooLarge)
+		}
+	}()
+	// TODO(http://golang.org/issue/51462): We should rely on the append-make
+	// pattern so that the compiler can call runtime.growslice. For example:
+	//	return append(b, make([]byte, n)...)
+	// This avoids unnecessary zero-ing of the first len(b) bytes of the
+	// allocated slice, but this pattern causes b to escape onto the heap.
+	//
+	// Instead use the append-make pattern with a nil slice to ensure that
+	// we allocate buffers rounded up to the closest size class.
+	c := len(b) + n // ensure enough space for n elements
+	if c < 2*cap(b) {
+		// The growth rate has historically always been 2x. In the future,
+		// we could rely purely on append to determine the growth rate.
+		c = 2 * cap(b)
+	}
+	b2 := append([]byte(nil), make([]byte, c)...)
+	copy(b2, b)
+	return b2[:len(b)]
+}
+
+// WriteTo writes data to w until the buffer is drained or an error occurs.
+// The return value n is the number of bytes written; it always fits into an
+// int, but it is int64 to match the io.WriterTo interface. Any error
+// encountered during the write is also returned.
+func (b *Buffer) WriteTo(w io.Writer) (n int64, err error) {
+	b.lastRead = opInvalid
+	if nBytes := b.Len(); nBytes > 0 {
+		m, e := w.Write(b.buf[b.off:])
+		if m > nBytes {
+			panic("bytes.Buffer.WriteTo: invalid Write count")
+		}
+		b.off += m
+		n = int64(m)
+		if e != nil {
+			return n, e
+		}
+		// all bytes should have been written, by definition of
+		// Write method in io.Writer
+		if m != nBytes {
+			return n, io.ErrShortWrite
+		}
+	}
+	// Buffer is now empty; reset.
+	b.Reset()
+	return n, nil
+}
+
+// WriteByte appends the byte c to the buffer, growing the buffer as needed.
+// The returned error is always nil, but is included to match bufio.Writer's
+// WriteByte. If the buffer becomes too large, WriteByte will panic with
+// ErrTooLarge.
+func (b *Buffer) WriteByte(c byte) error {
+	b.lastRead = opInvalid
+	m, ok := b.tryGrowByReslice(1)
+	if !ok {
+		m = b.grow(1)
+	}
+	b.buf[m] = c
+	return nil
+}
+
+// WriteRune appends the UTF-8 encoding of Unicode code point r to the
+// buffer, returning its length and an error, which is always nil but is
+// included to match bufio.Writer's WriteRune. The buffer is grown as needed;
+// if it becomes too large, WriteRune will panic with ErrTooLarge.
+func (b *Buffer) WriteRune(r rune) (n int, err error) {
+	// Compare as uint32 to correctly handle negative runes.
+	if uint32(r) < utf8.RuneSelf {
+		b.WriteByte(byte(r))
+		return 1, nil
+	}
+	b.lastRead = opInvalid
+	m, ok := b.tryGrowByReslice(utf8.UTFMax)
+	if !ok {
+		m = b.grow(utf8.UTFMax)
+	}
+	n = utf8.EncodeRune(b.buf[m:m+utf8.UTFMax], r)
+	b.buf = b.buf[:m+n]
+	return n, nil
+}
+
+// Read reads the next len(p) bytes from the buffer or until the buffer
+// is drained. The return value n is the number of bytes read. If the
+// buffer has no data to return, err is io.EOF (unless len(p) is zero);
+// otherwise it is nil.
+func (b *Buffer) Read(p []byte) (n int, err error) {
+	b.lastRead = opInvalid
+	if b.empty() {
+		// Buffer is empty, reset to recover space.
+		b.Reset()
+		if len(p) == 0 {
+			return 0, nil
+		}
+		return 0, io.EOF
+	}
+	n = copy(p, b.buf[b.off:])
+	b.off += n
+	if n > 0 {
+		b.lastRead = opRead
+	}
+	return n, nil
+}
+
+// Next returns a slice containing the next n bytes from the buffer,
+// advancing the buffer as if the bytes had been returned by Read.
+// If there are fewer than n bytes in the buffer, Next returns the entire buffer.
+// The slice is only valid until the next call to a read or write method.
+func (b *Buffer) Next(n int) []byte {
+	b.lastRead = opInvalid
+	m := b.Len()
+	if n > m {
+		n = m
+	}
+	data := b.buf[b.off : b.off+n]
+	b.off += n
+	if n > 0 {
+		b.lastRead = opRead
+	}
+	return data
+}
+
+// ReadByte reads and returns the next byte from the buffer.
+// If no byte is available, it returns error io.EOF.
+func (b *Buffer) ReadByte() (byte, error) {
+	if b.empty() {
+		// Buffer is empty, reset to recover space.
+		b.Reset()
+		return 0, io.EOF
+	}
+	c := b.buf[b.off]
+	b.off++
+	b.lastRead = opRead
+	return c, nil
+}
+
+// ReadRune reads and returns the next UTF-8-encoded
+// Unicode code point from the buffer.
+// If no bytes are available, the error returned is io.EOF.
+// If the bytes are an erroneous UTF-8 encoding, it
+// consumes one byte and returns U+FFFD, 1.
+func (b *Buffer) ReadRune() (r rune, size int, err error) {
+	if b.empty() {
+		// Buffer is empty, reset to recover space.
+		b.Reset()
+		return 0, 0, io.EOF
+	}
+	c := b.buf[b.off]
+	if c < utf8.RuneSelf {
+		b.off++
+		b.lastRead = opReadRune1
+		return rune(c), 1, nil
+	}
+	r, n := utf8.DecodeRune(b.buf[b.off:])
+	b.off += n
+	b.lastRead = readOp(n)
+	return r, n, nil
+}
+
+// UnreadRune unreads the last rune returned by ReadRune.
+// If the most recent read or write operation on the buffer was
+// not a successful ReadRune, UnreadRune returns an error.  (In this regard
+// it is stricter than UnreadByte, which will unread the last byte
+// from any read operation.)
+func (b *Buffer) UnreadRune() error {
+	if b.lastRead <= opInvalid {
+		return errors.New("bytes.Buffer: UnreadRune: previous operation was not a successful ReadRune")
+	}
+	if b.off >= int(b.lastRead) {
+		b.off -= int(b.lastRead)
+	}
+	b.lastRead = opInvalid
+	return nil
+}
+
+var errUnreadByte = errors.New("bytes.Buffer: UnreadByte: previous operation was not a successful read")
+
+// UnreadByte unreads the last byte returned by the most recent successful
+// read operation that read at least one byte. If a write has happened since
+// the last read, if the last read returned an error, or if the read read zero
+// bytes, UnreadByte returns an error.
+func (b *Buffer) UnreadByte() error {
+	if b.lastRead == opInvalid {
+		return errUnreadByte
+	}
+	b.lastRead = opInvalid
+	if b.off > 0 {
+		b.off--
+	}
+	return nil
+}
+
+// ReadBytes reads until the first occurrence of delim in the input,
+// returning a slice containing the data up to and including the delimiter.
+// If ReadBytes encounters an error before finding a delimiter,
+// it returns the data read before the error and the error itself (often io.EOF).
+// ReadBytes returns err != nil if and only if the returned data does not end in
+// delim.
+func (b *Buffer) ReadBytes(delim byte) (line []byte, err error) {
+	slice, err := b.readSlice(delim)
+	// return a copy of slice. The buffer's backing array may
+	// be overwritten by later calls.
+	line = append(line, slice...)
+	return line, err
+}
+
+// readSlice is like ReadBytes but returns a reference to internal buffer data.
+func (b *Buffer) readSlice(delim byte) (line []byte, err error) {
+	i := IndexByte(b.buf[b.off:], delim)
+	end := b.off + i + 1
+	if i < 0 {
+		end = len(b.buf)
+		err = io.EOF
+	}
+	line = b.buf[b.off:end]
+	b.off = end
+	b.lastRead = opRead
+	return line, err
+}
+
+// ReadString reads until the first occurrence of delim in the input,
+// returning a string containing the data up to and including the delimiter.
+// If ReadString encounters an error before finding a delimiter,
+// it returns the data read before the error and the error itself (often io.EOF).
+// ReadString returns err != nil if and only if the returned data does not end
+// in delim.
+func (b *Buffer) ReadString(delim byte) (line string, err error) {
+	slice, err := b.readSlice(delim)
+	return string(slice), err
+}
+
+// NewBuffer creates and initializes a new Buffer using buf as its
+// initial contents. The new Buffer takes ownership of buf, and the
+// caller should not use buf after this call. NewBuffer is intended to
+// prepare a Buffer to read existing data. It can also be used to set
+// the initial size of the internal buffer for writing. To do that,
+// buf should have the desired capacity but a length of zero.
+//
+// In most cases, new(Buffer) (or just declaring a Buffer variable) is
+// sufficient to initialize a Buffer.
+func NewBuffer(buf []byte) *Buffer { return &Buffer{buf: buf} }
+
+// NewBufferString creates and initializes a new Buffer using string s as its
+// initial contents. It is intended to prepare a buffer to read an existing
+// string.
+//
+// In most cases, new(Buffer) (or just declaring a Buffer variable) is
+// sufficient to initialize a Buffer.
+func NewBufferString(s string) *Buffer {
+	return &Buffer{buf: []byte(s)}
+}
diff --git a/contrib/go/_std_1.19/src/bytes/bytes.go b/contrib/go/_std_1.19/src/bytes/bytes.go
new file mode 100644
index 0000000000..659a82bcc8
--- /dev/null
+++ b/contrib/go/_std_1.19/src/bytes/bytes.go
@@ -0,0 +1,1301 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package bytes implements functions for the manipulation of byte slices.
+// It is analogous to the facilities of the strings package.
+package bytes
+
+import (
+	"internal/bytealg"
+	"unicode"
+	"unicode/utf8"
+)
+
+// Equal reports whether a and b
+// are the same length and contain the same bytes.
+// A nil argument is equivalent to an empty slice.
+func Equal(a, b []byte) bool {
+	// Neither cmd/compile nor gccgo allocates for these string conversions.
+	return string(a) == string(b)
+}
+
+// Compare returns an integer comparing two byte slices lexicographically.
+// The result will be 0 if a == b, -1 if a < b, and +1 if a > b.
+// A nil argument is equivalent to an empty slice.
+func Compare(a, b []byte) int {
+	return bytealg.Compare(a, b)
+}
+
+// explode splits s into a slice of UTF-8 sequences, one per Unicode code point (still slices of bytes),
+// up to a maximum of n byte slices. Invalid UTF-8 sequences are chopped into individual bytes.
+func explode(s []byte, n int) [][]byte {
+	if n <= 0 || n > len(s) {
+		n = len(s)
+	}
+	a := make([][]byte, n)
+	var size int
+	na := 0
+	for len(s) > 0 {
+		if na+1 >= n {
+			a[na] = s
+			na++
+			break
+		}
+		_, size = utf8.DecodeRune(s)
+		a[na] = s[0:size:size]
+		s = s[size:]
+		na++
+	}
+	return a[0:na]
+}
+
+// Count counts the number of non-overlapping instances of sep in s.
+// If sep is an empty slice, Count returns 1 + the number of UTF-8-encoded code points in s.
+func Count(s, sep []byte) int {
+	// special case
+	if len(sep) == 0 {
+		return utf8.RuneCount(s) + 1
+	}
+	if len(sep) == 1 {
+		return bytealg.Count(s, sep[0])
+	}
+	n := 0
+	for {
+		i := Index(s, sep)
+		if i == -1 {
+			return n
+		}
+		n++
+		s = s[i+len(sep):]
+	}
+}
+
+// Contains reports whether subslice is within b.
+func Contains(b, subslice []byte) bool {
+	return Index(b, subslice) != -1
+}
+
+// ContainsAny reports whether any of the UTF-8-encoded code points in chars are within b.
+func ContainsAny(b []byte, chars string) bool {
+	return IndexAny(b, chars) >= 0
+}
+
+// ContainsRune reports whether the rune is contained in the UTF-8-encoded byte slice b.
+func ContainsRune(b []byte, r rune) bool {
+	return IndexRune(b, r) >= 0
+}
+
+// IndexByte returns the index of the first instance of c in b, or -1 if c is not present in b.
+func IndexByte(b []byte, c byte) int {
+	return bytealg.IndexByte(b, c)
+}
+
+func indexBytePortable(s []byte, c byte) int {
+	for i, b := range s {
+		if b == c {
+			return i
+		}
+	}
+	return -1
+}
+
+// LastIndex returns the index of the last instance of sep in s, or -1 if sep is not present in s.
+func LastIndex(s, sep []byte) int {
+	n := len(sep)
+	switch {
+	case n == 0:
+		return len(s)
+	case n == 1:
+		return LastIndexByte(s, sep[0])
+	case n == len(s):
+		if Equal(s, sep) {
+			return 0
+		}
+		return -1
+	case n > len(s):
+		return -1
+	}
+	// Rabin-Karp search from the end of the string
+	hashss, pow := bytealg.HashStrRevBytes(sep)
+	last := len(s) - n
+	var h uint32
+	for i := len(s) - 1; i >= last; i-- {
+		h = h*bytealg.PrimeRK + uint32(s[i])
+	}
+	if h == hashss && Equal(s[last:], sep) {
+		return last
+	}
+	for i := last - 1; i >= 0; i-- {
+		h *= bytealg.PrimeRK
+		h += uint32(s[i])
+		h -= pow * uint32(s[i+n])
+		if h == hashss && Equal(s[i:i+n], sep) {
+			return i
+		}
+	}
+	return -1
+}
+
+// LastIndexByte returns the index of the last instance of c in s, or -1 if c is not present in s.
+func LastIndexByte(s []byte, c byte) int {
+	for i := len(s) - 1; i >= 0; i-- {
+		if s[i] == c {
+			return i
+		}
+	}
+	return -1
+}
+
+// IndexRune interprets s as a sequence of UTF-8-encoded code points.
+// It returns the byte index of the first occurrence in s of the given rune.
+// It returns -1 if rune is not present in s.
+// If r is utf8.RuneError, it returns the first instance of any
+// invalid UTF-8 byte sequence.
+func IndexRune(s []byte, r rune) int {
+	switch {
+	case 0 <= r && r < utf8.RuneSelf:
+		return IndexByte(s, byte(r))
+	case r == utf8.RuneError:
+		for i := 0; i < len(s); {
+			r1, n := utf8.DecodeRune(s[i:])
+			if r1 == utf8.RuneError {
+				return i
+			}
+			i += n
+		}
+		return -1
+	case !utf8.ValidRune(r):
+		return -1
+	default:
+		var b [utf8.UTFMax]byte
+		n := utf8.EncodeRune(b[:], r)
+		return Index(s, b[:n])
+	}
+}
+
+// IndexAny interprets s as a sequence of UTF-8-encoded Unicode code points.
+// It returns the byte index of the first occurrence in s of any of the Unicode
+// code points in chars. It returns -1 if chars is empty or if there is no code
+// point in common.
+func IndexAny(s []byte, chars string) int {
+	if chars == "" {
+		// Avoid scanning all of s.
+		return -1
+	}
+	if len(s) == 1 {
+		r := rune(s[0])
+		if r >= utf8.RuneSelf {
+			// search utf8.RuneError.
+			for _, r = range chars {
+				if r == utf8.RuneError {
+					return 0
+				}
+			}
+			return -1
+		}
+		if bytealg.IndexByteString(chars, s[0]) >= 0 {
+			return 0
+		}
+		return -1
+	}
+	if len(chars) == 1 {
+		r := rune(chars[0])
+		if r >= utf8.RuneSelf {
+			r = utf8.RuneError
+		}
+		return IndexRune(s, r)
+	}
+	if len(s) > 8 {
+		if as, isASCII := makeASCIISet(chars); isASCII {
+			for i, c := range s {
+				if as.contains(c) {
+					return i
+				}
+			}
+			return -1
+		}
+	}
+	var width int
+	for i := 0; i < len(s); i += width {
+		r := rune(s[i])
+		if r < utf8.RuneSelf {
+			if bytealg.IndexByteString(chars, s[i]) >= 0 {
+				return i
+			}
+			width = 1
+			continue
+		}
+		r, width = utf8.DecodeRune(s[i:])
+		if r != utf8.RuneError {
+			// r is 2 to 4 bytes
+			if len(chars) == width {
+				if chars == string(r) {
+					return i
+				}
+				continue
+			}
+			// Use bytealg.IndexString for performance if available.
+			if bytealg.MaxLen >= width {
+				if bytealg.IndexString(chars, string(r)) >= 0 {
+					return i
+				}
+				continue
+			}
+		}
+		for _, ch := range chars {
+			if r == ch {
+				return i
+			}
+		}
+	}
+	return -1
+}
+
+// LastIndexAny interprets s as a sequence of UTF-8-encoded Unicode code
+// points. It returns the byte index of the last occurrence in s of any of
+// the Unicode code points in chars. It returns -1 if chars is empty or if
+// there is no code point in common.
+func LastIndexAny(s []byte, chars string) int {
+	if chars == "" {
+		// Avoid scanning all of s.
+		return -1
+	}
+	if len(s) > 8 {
+		if as, isASCII := makeASCIISet(chars); isASCII {
+			for i := len(s) - 1; i >= 0; i-- {
+				if as.contains(s[i]) {
+					return i
+				}
+			}
+			return -1
+		}
+	}
+	if len(s) == 1 {
+		r := rune(s[0])
+		if r >= utf8.RuneSelf {
+			for _, r = range chars {
+				if r == utf8.RuneError {
+					return 0
+				}
+			}
+			return -1
+		}
+		if bytealg.IndexByteString(chars, s[0]) >= 0 {
+			return 0
+		}
+		return -1
+	}
+	if len(chars) == 1 {
+		cr := rune(chars[0])
+		if cr >= utf8.RuneSelf {
+			cr = utf8.RuneError
+		}
+		for i := len(s); i > 0; {
+			r, size := utf8.DecodeLastRune(s[:i])
+			i -= size
+			if r == cr {
+				return i
+			}
+		}
+		return -1
+	}
+	for i := len(s); i > 0; {
+		r := rune(s[i-1])
+		if r < utf8.RuneSelf {
+			if bytealg.IndexByteString(chars, s[i-1]) >= 0 {
+				return i - 1
+			}
+			i--
+			continue
+		}
+		r, size := utf8.DecodeLastRune(s[:i])
+		i -= size
+		if r != utf8.RuneError {
+			// r is 2 to 4 bytes
+			if len(chars) == size {
+				if chars == string(r) {
+					return i
+				}
+				continue
+			}
+			// Use bytealg.IndexString for performance if available.
+			if bytealg.MaxLen >= size {
+				if bytealg.IndexString(chars, string(r)) >= 0 {
+					return i
+				}
+				continue
+			}
+		}
+		for _, ch := range chars {
+			if r == ch {
+				return i
+			}
+		}
+	}
+	return -1
+}
+
+// Generic split: splits after each instance of sep,
+// including sepSave bytes of sep in the subslices.
+func genSplit(s, sep []byte, sepSave, n int) [][]byte {
+	if n == 0 {
+		return nil
+	}
+	if len(sep) == 0 {
+		return explode(s, n)
+	}
+	if n < 0 {
+		n = Count(s, sep) + 1
+	}
+	if n > len(s)+1 {
+		n = len(s) + 1
+	}
+
+	a := make([][]byte, n)
+	n--
+	i := 0
+	for i < n {
+		m := Index(s, sep)
+		if m < 0 {
+			break
+		}
+		a[i] = s[: m+sepSave : m+sepSave]
+		s = s[m+len(sep):]
+		i++
+	}
+	a[i] = s
+	return a[:i+1]
+}
+
+// SplitN slices s into subslices separated by sep and returns a slice of
+// the subslices between those separators.
+// If sep is empty, SplitN splits after each UTF-8 sequence.
+// The count determines the number of subslices to return:
+//
+//	n > 0: at most n subslices; the last subslice will be the unsplit remainder.
+//	n == 0: the result is nil (zero subslices)
+//	n < 0: all subslices
+//
+// To split around the first instance of a separator, see Cut.
+func SplitN(s, sep []byte, n int) [][]byte { return genSplit(s, sep, 0, n) }
+
+// SplitAfterN slices s into subslices after each instance of sep and
+// returns a slice of those subslices.
+// If sep is empty, SplitAfterN splits after each UTF-8 sequence.
+// The count determines the number of subslices to return:
+//
+//	n > 0: at most n subslices; the last subslice will be the unsplit remainder.
+//	n == 0: the result is nil (zero subslices)
+//	n < 0: all subslices
+func SplitAfterN(s, sep []byte, n int) [][]byte {
+	return genSplit(s, sep, len(sep), n)
+}
+
+// Split slices s into all subslices separated by sep and returns a slice of
+// the subslices between those separators.
+// If sep is empty, Split splits after each UTF-8 sequence.
+// It is equivalent to SplitN with a count of -1.
+//
+// To split around the first instance of a separator, see Cut.
+func Split(s, sep []byte) [][]byte { return genSplit(s, sep, 0, -1) }
+
+// SplitAfter slices s into all subslices after each instance of sep and
+// returns a slice of those subslices.
+// If sep is empty, SplitAfter splits after each UTF-8 sequence.
+// It is equivalent to SplitAfterN with a count of -1.
+func SplitAfter(s, sep []byte) [][]byte {
+	return genSplit(s, sep, len(sep), -1)
+}
+
+var asciiSpace = [256]uint8{'\t': 1, '\n': 1, '\v': 1, '\f': 1, '\r': 1, ' ': 1}
+
+// Fields interprets s as a sequence of UTF-8-encoded code points.
+// It splits the slice s around each instance of one or more consecutive white space
+// characters, as defined by unicode.IsSpace, returning a slice of subslices of s or an
+// empty slice if s contains only white space.
+func Fields(s []byte) [][]byte {
+	// First count the fields.
+	// This is an exact count if s is ASCII, otherwise it is an approximation.
+	n := 0
+	wasSpace := 1
+	// setBits is used to track which bits are set in the bytes of s.
+	setBits := uint8(0)
+	for i := 0; i < len(s); i++ {
+		r := s[i]
+		setBits |= r
+		isSpace := int(asciiSpace[r])
+		n += wasSpace & ^isSpace
+		wasSpace = isSpace
+	}
+
+	if setBits >= utf8.RuneSelf {
+		// Some runes in the input slice are not ASCII.
+		return FieldsFunc(s, unicode.IsSpace)
+	}
+
+	// ASCII fast path
+	a := make([][]byte, n)
+	na := 0
+	fieldStart := 0
+	i := 0
+	// Skip spaces in the front of the input.
+	for i < len(s) && asciiSpace[s[i]] != 0 {
+		i++
+	}
+	fieldStart = i
+	for i < len(s) {
+		if asciiSpace[s[i]] == 0 {
+			i++
+			continue
+		}
+		a[na] = s[fieldStart:i:i]
+		na++
+		i++
+		// Skip spaces in between fields.
+		for i < len(s) && asciiSpace[s[i]] != 0 {
+			i++
+		}
+		fieldStart = i
+	}
+	if fieldStart < len(s) { // Last field might end at EOF.
+		a[na] = s[fieldStart:len(s):len(s)]
+	}
+	return a
+}
+
+// FieldsFunc interprets s as a sequence of UTF-8-encoded code points.
+// It splits the slice s at each run of code points c satisfying f(c) and
+// returns a slice of subslices of s. If all code points in s satisfy f(c), or
+// len(s) == 0, an empty slice is returned.
+//
+// FieldsFunc makes no guarantees about the order in which it calls f(c)
+// and assumes that f always returns the same value for a given c.
+func FieldsFunc(s []byte, f func(rune) bool) [][]byte {
+	// A span is used to record a slice of s of the form s[start:end].
+	// The start index is inclusive and the end index is exclusive.
+	type span struct {
+		start int
+		end   int
+	}
+	spans := make([]span, 0, 32)
+
+	// Find the field start and end indices.
+	// Doing this in a separate pass (rather than slicing the string s
+	// and collecting the result substrings right away) is significantly
+	// more efficient, possibly due to cache effects.
+	start := -1 // valid span start if >= 0
+	for i := 0; i < len(s); {
+		size := 1
+		r := rune(s[i])
+		if r >= utf8.RuneSelf {
+			r, size = utf8.DecodeRune(s[i:])
+		}
+		if f(r) {
+			if start >= 0 {
+				spans = append(spans, span{start, i})
+				start = -1
+			}
+		} else {
+			if start < 0 {
+				start = i
+			}
+		}
+		i += size
+	}
+
+	// Last field might end at EOF.
+	if start >= 0 {
+		spans = append(spans, span{start, len(s)})
+	}
+
+	// Create subslices from recorded field indices.
+	a := make([][]byte, len(spans))
+	for i, span := range spans {
+		a[i] = s[span.start:span.end:span.end]
+	}
+
+	return a
+}
+
+// Join concatenates the elements of s to create a new byte slice. The separator
+// sep is placed between elements in the resulting slice.
+func Join(s [][]byte, sep []byte) []byte {
+	if len(s) == 0 {
+		return []byte{}
+	}
+	if len(s) == 1 {
+		// Just return a copy.
+		return append([]byte(nil), s[0]...)
+	}
+	n := len(sep) * (len(s) - 1)
+	for _, v := range s {
+		n += len(v)
+	}
+
+	b := make([]byte, n)
+	bp := copy(b, s[0])
+	for _, v := range s[1:] {
+		bp += copy(b[bp:], sep)
+		bp += copy(b[bp:], v)
+	}
+	return b
+}
+
+// HasPrefix tests whether the byte slice s begins with prefix.
+func HasPrefix(s, prefix []byte) bool {
+	return len(s) >= len(prefix) && Equal(s[0:len(prefix)], prefix)
+}
+
+// HasSuffix tests whether the byte slice s ends with suffix.
+func HasSuffix(s, suffix []byte) bool {
+	return len(s) >= len(suffix) && Equal(s[len(s)-len(suffix):], suffix)
+}
+
+// Map returns a copy of the byte slice s with all its characters modified
+// according to the mapping function. If mapping returns a negative value, the character is
+// dropped from the byte slice with no replacement. The characters in s and the
+// output are interpreted as UTF-8-encoded code points.
+func Map(mapping func(r rune) rune, s []byte) []byte {
+	// In the worst case, the slice can grow when mapped, making
+	// things unpleasant. But it's so rare we barge in assuming it's
+	// fine. It could also shrink but that falls out naturally.
+	maxbytes := len(s) // length of b
+	nbytes := 0        // number of bytes encoded in b
+	b := make([]byte, maxbytes)
+	for i := 0; i < len(s); {
+		wid := 1
+		r := rune(s[i])
+		if r >= utf8.RuneSelf {
+			r, wid = utf8.DecodeRune(s[i:])
+		}
+		r = mapping(r)
+		if r >= 0 {
+			rl := utf8.RuneLen(r)
+			if rl < 0 {
+				rl = len(string(utf8.RuneError))
+			}
+			if nbytes+rl > maxbytes {
+				// Grow the buffer.
+				maxbytes = maxbytes*2 + utf8.UTFMax
+				nb := make([]byte, maxbytes)
+				copy(nb, b[0:nbytes])
+				b = nb
+			}
+			nbytes += utf8.EncodeRune(b[nbytes:maxbytes], r)
+		}
+		i += wid
+	}
+	return b[0:nbytes]
+}
+
+// Repeat returns a new byte slice consisting of count copies of b.
+//
+// It panics if count is negative or if
+// the result of (len(b) * count) overflows.
+func Repeat(b []byte, count int) []byte {
+	if count == 0 {
+		return []byte{}
+	}
+	// Since we cannot return an error on overflow,
+	// we should panic if the repeat will generate
+	// an overflow.
+	// See Issue golang.org/issue/16237.
+	if count < 0 {
+		panic("bytes: negative Repeat count")
+	} else if len(b)*count/count != len(b) {
+		panic("bytes: Repeat count causes overflow")
+	}
+
+	nb := make([]byte, len(b)*count)
+	bp := copy(nb, b)
+	for bp < len(nb) {
+		copy(nb[bp:], nb[:bp])
+		bp *= 2
+	}
+	return nb
+}
+
+// ToUpper returns a copy of the byte slice s with all Unicode letters mapped to
+// their upper case.
+func ToUpper(s []byte) []byte {
+	isASCII, hasLower := true, false
+	for i := 0; i < len(s); i++ {
+		c := s[i]
+		if c >= utf8.RuneSelf {
+			isASCII = false
+			break
+		}
+		hasLower = hasLower || ('a' <= c && c <= 'z')
+	}
+
+	if isASCII { // optimize for ASCII-only byte slices.
+		if !hasLower {
+			// Just return a copy.
+			return append([]byte(""), s...)
+		}
+		b := make([]byte, len(s))
+		for i := 0; i < len(s); i++ {
+			c := s[i]
+			if 'a' <= c && c <= 'z' {
+				c -= 'a' - 'A'
+			}
+			b[i] = c
+		}
+		return b
+	}
+	return Map(unicode.ToUpper, s)
+}
+
+// ToLower returns a copy of the byte slice s with all Unicode letters mapped to
+// their lower case.
+func ToLower(s []byte) []byte {
+	isASCII, hasUpper := true, false
+	for i := 0; i < len(s); i++ {
+		c := s[i]
+		if c >= utf8.RuneSelf {
+			isASCII = false
+			break
+		}
+		hasUpper = hasUpper || ('A' <= c && c <= 'Z')
+	}
+
+	if isASCII { // optimize for ASCII-only byte slices.
+		if !hasUpper {
+			return append([]byte(""), s...)
+		}
+		b := make([]byte, len(s))
+		for i := 0; i < len(s); i++ {
+			c := s[i]
+			if 'A' <= c && c <= 'Z' {
+				c += 'a' - 'A'
+			}
+			b[i] = c
+		}
+		return b
+	}
+	return Map(unicode.ToLower, s)
+}
+
+// ToTitle treats s as UTF-8-encoded bytes and returns a copy with all the Unicode letters mapped to their title case.
+func ToTitle(s []byte) []byte { return Map(unicode.ToTitle, s) }
+
+// ToUpperSpecial treats s as UTF-8-encoded bytes and returns a copy with all the Unicode letters mapped to their
+// upper case, giving priority to the special casing rules.
+func ToUpperSpecial(c unicode.SpecialCase, s []byte) []byte {
+	return Map(c.ToUpper, s)
+}
+
+// ToLowerSpecial treats s as UTF-8-encoded bytes and returns a copy with all the Unicode letters mapped to their
+// lower case, giving priority to the special casing rules.
+func ToLowerSpecial(c unicode.SpecialCase, s []byte) []byte {
+	return Map(c.ToLower, s)
+}
+
+// ToTitleSpecial treats s as UTF-8-encoded bytes and returns a copy with all the Unicode letters mapped to their
+// title case, giving priority to the special casing rules.
+func ToTitleSpecial(c unicode.SpecialCase, s []byte) []byte {
+	return Map(c.ToTitle, s)
+}
+
+// ToValidUTF8 treats s as UTF-8-encoded bytes and returns a copy with each run of bytes
+// representing invalid UTF-8 replaced with the bytes in replacement, which may be empty.
+func ToValidUTF8(s, replacement []byte) []byte {
+	b := make([]byte, 0, len(s)+len(replacement))
+	invalid := false // previous byte was from an invalid UTF-8 sequence
+	for i := 0; i < len(s); {
+		c := s[i]
+		if c < utf8.RuneSelf {
+			i++
+			invalid = false
+			b = append(b, c)
+			continue
+		}
+		_, wid := utf8.DecodeRune(s[i:])
+		if wid == 1 {
+			i++
+			if !invalid {
+				invalid = true
+				b = append(b, replacement...)
+			}
+			continue
+		}
+		invalid = false
+		b = append(b, s[i:i+wid]...)
+		i += wid
+	}
+	return b
+}
+
+// isSeparator reports whether the rune could mark a word boundary.
+// TODO: update when package unicode captures more of the properties.
+func isSeparator(r rune) bool {
+	// ASCII alphanumerics and underscore are not separators
+	if r <= 0x7F {
+		switch {
+		case '0' <= r && r <= '9':
+			return false
+		case 'a' <= r && r <= 'z':
+			return false
+		case 'A' <= r && r <= 'Z':
+			return false
+		case r == '_':
+			return false
+		}
+		return true
+	}
+	// Letters and digits are not separators
+	if unicode.IsLetter(r) || unicode.IsDigit(r) {
+		return false
+	}
+	// Otherwise, all we can do for now is treat spaces as separators.
+	return unicode.IsSpace(r)
+}
+
+// Title treats s as UTF-8-encoded bytes and returns a copy with all Unicode letters that begin
+// words mapped to their title case.
+//
+// Deprecated: The rule Title uses for word boundaries does not handle Unicode
+// punctuation properly. Use golang.org/x/text/cases instead.
+func Title(s []byte) []byte {
+	// Use a closure here to remember state.
+	// Hackish but effective. Depends on Map scanning in order and calling
+	// the closure once per rune.
+	prev := ' '
+	return Map(
+		func(r rune) rune {
+			if isSeparator(prev) {
+				prev = r
+				return unicode.ToTitle(r)
+			}
+			prev = r
+			return r
+		},
+		s)
+}
+
+// TrimLeftFunc treats s as UTF-8-encoded bytes and returns a subslice of s by slicing off
+// all leading UTF-8-encoded code points c that satisfy f(c).
+func TrimLeftFunc(s []byte, f func(r rune) bool) []byte {
+	i := indexFunc(s, f, false)
+	if i == -1 {
+		return nil
+	}
+	return s[i:]
+}
+
+// TrimRightFunc returns a subslice of s by slicing off all trailing
+// UTF-8-encoded code points c that satisfy f(c).
+func TrimRightFunc(s []byte, f func(r rune) bool) []byte {
+	i := lastIndexFunc(s, f, false)
+	if i >= 0 && s[i] >= utf8.RuneSelf {
+		_, wid := utf8.DecodeRune(s[i:])
+		i += wid
+	} else {
+		i++
+	}
+	return s[0:i]
+}
+
+// TrimFunc returns a subslice of s by slicing off all leading and trailing
+// UTF-8-encoded code points c that satisfy f(c).
+func TrimFunc(s []byte, f func(r rune) bool) []byte {
+	return TrimRightFunc(TrimLeftFunc(s, f), f)
+}
+
+// TrimPrefix returns s without the provided leading prefix string.
+// If s doesn't start with prefix, s is returned unchanged.
+func TrimPrefix(s, prefix []byte) []byte {
+	if HasPrefix(s, prefix) {
+		return s[len(prefix):]
+	}
+	return s
+}
+
+// TrimSuffix returns s without the provided trailing suffix string.
+// If s doesn't end with suffix, s is returned unchanged.
+func TrimSuffix(s, suffix []byte) []byte {
+	if HasSuffix(s, suffix) {
+		return s[:len(s)-len(suffix)]
+	}
+	return s
+}
+
+// IndexFunc interprets s as a sequence of UTF-8-encoded code points.
+// It returns the byte index in s of the first Unicode
+// code point satisfying f(c), or -1 if none do.
+func IndexFunc(s []byte, f func(r rune) bool) int {
+	return indexFunc(s, f, true)
+}
+
+// LastIndexFunc interprets s as a sequence of UTF-8-encoded code points.
+// It returns the byte index in s of the last Unicode
+// code point satisfying f(c), or -1 if none do.
+func LastIndexFunc(s []byte, f func(r rune) bool) int {
+	return lastIndexFunc(s, f, true)
+}
+
+// indexFunc is the same as IndexFunc except that if
+// truth==false, the sense of the predicate function is
+// inverted.
+func indexFunc(s []byte, f func(r rune) bool, truth bool) int {
+	start := 0
+	for start < len(s) {
+		wid := 1
+		r := rune(s[start])
+		if r >= utf8.RuneSelf {
+			r, wid = utf8.DecodeRune(s[start:])
+		}
+		if f(r) == truth {
+			return start
+		}
+		start += wid
+	}
+	return -1
+}
+
+// lastIndexFunc is the same as LastIndexFunc except that if
+// truth==false, the sense of the predicate function is
+// inverted.
+func lastIndexFunc(s []byte, f func(r rune) bool, truth bool) int {
+	for i := len(s); i > 0; {
+		r, size := rune(s[i-1]), 1
+		if r >= utf8.RuneSelf {
+			r, size = utf8.DecodeLastRune(s[0:i])
+		}
+		i -= size
+		if f(r) == truth {
+			return i
+		}
+	}
+	return -1
+}
+
+// asciiSet is a 32-byte value, where each bit represents the presence of a
+// given ASCII character in the set. The 128-bits of the lower 16 bytes,
+// starting with the least-significant bit of the lowest word to the
+// most-significant bit of the highest word, map to the full range of all
+// 128 ASCII characters. The 128-bits of the upper 16 bytes will be zeroed,
+// ensuring that any non-ASCII character will be reported as not in the set.
+// This allocates a total of 32 bytes even though the upper half
+// is unused to avoid bounds checks in asciiSet.contains.
+type asciiSet [8]uint32
+
+// makeASCIISet creates a set of ASCII characters and reports whether all
+// characters in chars are ASCII.
+func makeASCIISet(chars string) (as asciiSet, ok bool) {
+	for i := 0; i < len(chars); i++ {
+		c := chars[i]
+		if c >= utf8.RuneSelf {
+			return as, false
+		}
+		as[c/32] |= 1 << (c % 32)
+	}
+	return as, true
+}
+
+// contains reports whether c is inside the set.
+func (as *asciiSet) contains(c byte) bool {
+	return (as[c/32] & (1 << (c % 32))) != 0
+}
+
+// containsRune is a simplified version of strings.ContainsRune
+// to avoid importing the strings package.
+// We avoid bytes.ContainsRune to avoid allocating a temporary copy of s.
+func containsRune(s string, r rune) bool {
+	for _, c := range s {
+		if c == r {
+			return true
+		}
+	}
+	return false
+}
+
+// Trim returns a subslice of s by slicing off all leading and
+// trailing UTF-8-encoded code points contained in cutset.
+func Trim(s []byte, cutset string) []byte {
+	if len(s) == 0 {
+		// This is what we've historically done.
+		return nil
+	}
+	if cutset == "" {
+		return s
+	}
+	if len(cutset) == 1 && cutset[0] < utf8.RuneSelf {
+		return trimLeftByte(trimRightByte(s, cutset[0]), cutset[0])
+	}
+	if as, ok := makeASCIISet(cutset); ok {
+		return trimLeftASCII(trimRightASCII(s, &as), &as)
+	}
+	return trimLeftUnicode(trimRightUnicode(s, cutset), cutset)
+}
+
+// TrimLeft returns a subslice of s by slicing off all leading
+// UTF-8-encoded code points contained in cutset.
+func TrimLeft(s []byte, cutset string) []byte {
+	if len(s) == 0 {
+		// This is what we've historically done.
+		return nil
+	}
+	if cutset == "" {
+		return s
+	}
+	if len(cutset) == 1 && cutset[0] < utf8.RuneSelf {
+		return trimLeftByte(s, cutset[0])
+	}
+	if as, ok := makeASCIISet(cutset); ok {
+		return trimLeftASCII(s, &as)
+	}
+	return trimLeftUnicode(s, cutset)
+}
+
+func trimLeftByte(s []byte, c byte) []byte {
+	for len(s) > 0 && s[0] == c {
+		s = s[1:]
+	}
+	if len(s) == 0 {
+		// This is what we've historically done.
+		return nil
+	}
+	return s
+}
+
+func trimLeftASCII(s []byte, as *asciiSet) []byte {
+	for len(s) > 0 {
+		if !as.contains(s[0]) {
+			break
+		}
+		s = s[1:]
+	}
+	if len(s) == 0 {
+		// This is what we've historically done.
+		return nil
+	}
+	return s
+}
+
+func trimLeftUnicode(s []byte, cutset string) []byte {
+	for len(s) > 0 {
+		r, n := rune(s[0]), 1
+		if r >= utf8.RuneSelf {
+			r, n = utf8.DecodeRune(s)
+		}
+		if !containsRune(cutset, r) {
+			break
+		}
+		s = s[n:]
+	}
+	if len(s) == 0 {
+		// This is what we've historically done.
+		return nil
+	}
+	return s
+}
+
+// TrimRight returns a subslice of s by slicing off all trailing
+// UTF-8-encoded code points that are contained in cutset.
+func TrimRight(s []byte, cutset string) []byte {
+	if len(s) == 0 || cutset == "" {
+		return s
+	}
+	if len(cutset) == 1 && cutset[0] < utf8.RuneSelf {
+		return trimRightByte(s, cutset[0])
+	}
+	if as, ok := makeASCIISet(cutset); ok {
+		return trimRightASCII(s, &as)
+	}
+	return trimRightUnicode(s, cutset)
+}
+
+func trimRightByte(s []byte, c byte) []byte {
+	for len(s) > 0 && s[len(s)-1] == c {
+		s = s[:len(s)-1]
+	}
+	return s
+}
+
+func trimRightASCII(s []byte, as *asciiSet) []byte {
+	for len(s) > 0 {
+		if !as.contains(s[len(s)-1]) {
+			break
+		}
+		s = s[:len(s)-1]
+	}
+	return s
+}
+
+func trimRightUnicode(s []byte, cutset string) []byte {
+	for len(s) > 0 {
+		r, n := rune(s[len(s)-1]), 1
+		if r >= utf8.RuneSelf {
+			r, n = utf8.DecodeLastRune(s)
+		}
+		if !containsRune(cutset, r) {
+			break
+		}
+		s = s[:len(s)-n]
+	}
+	return s
+}
+
+// TrimSpace returns a subslice of s by slicing off all leading and
+// trailing white space, as defined by Unicode.
+func TrimSpace(s []byte) []byte {
+	// Fast path for ASCII: look for the first ASCII non-space byte
+	start := 0
+	for ; start < len(s); start++ {
+		c := s[start]
+		if c >= utf8.RuneSelf {
+			// If we run into a non-ASCII byte, fall back to the
+			// slower unicode-aware method on the remaining bytes
+			return TrimFunc(s[start:], unicode.IsSpace)
+		}
+		if asciiSpace[c] == 0 {
+			break
+		}
+	}
+
+	// Now look for the first ASCII non-space byte from the end
+	stop := len(s)
+	for ; stop > start; stop-- {
+		c := s[stop-1]
+		if c >= utf8.RuneSelf {
+			return TrimFunc(s[start:stop], unicode.IsSpace)
+		}
+		if asciiSpace[c] == 0 {
+			break
+		}
+	}
+
+	// At this point s[start:stop] starts and ends with an ASCII
+	// non-space bytes, so we're done. Non-ASCII cases have already
+	// been handled above.
+	if start == stop {
+		// Special case to preserve previous TrimLeftFunc behavior,
+		// returning nil instead of empty slice if all spaces.
+		return nil
+	}
+	return s[start:stop]
+}
+
+// Runes interprets s as a sequence of UTF-8-encoded code points.
+// It returns a slice of runes (Unicode code points) equivalent to s.
+func Runes(s []byte) []rune {
+	t := make([]rune, utf8.RuneCount(s))
+	i := 0
+	for len(s) > 0 {
+		r, l := utf8.DecodeRune(s)
+		t[i] = r
+		i++
+		s = s[l:]
+	}
+	return t
+}
+
+// Replace returns a copy of the slice s with the first n
+// non-overlapping instances of old replaced by new.
+// If old is empty, it matches at the beginning of the slice
+// and after each UTF-8 sequence, yielding up to k+1 replacements
+// for a k-rune slice.
+// If n < 0, there is no limit on the number of replacements.
+func Replace(s, old, new []byte, n int) []byte {
+	m := 0
+	if n != 0 {
+		// Compute number of replacements.
+		m = Count(s, old)
+	}
+	if m == 0 {
+		// Just return a copy.
+		return append([]byte(nil), s...)
+	}
+	if n < 0 || m < n {
+		n = m
+	}
+
+	// Apply replacements to buffer.
+	t := make([]byte, len(s)+n*(len(new)-len(old)))
+	w := 0
+	start := 0
+	for i := 0; i < n; i++ {
+		j := start
+		if len(old) == 0 {
+			if i > 0 {
+				_, wid := utf8.DecodeRune(s[start:])
+				j += wid
+			}
+		} else {
+			j += Index(s[start:], old)
+		}
+		w += copy(t[w:], s[start:j])
+		w += copy(t[w:], new)
+		start = j + len(old)
+	}
+	w += copy(t[w:], s[start:])
+	return t[0:w]
+}
+
+// ReplaceAll returns a copy of the slice s with all
+// non-overlapping instances of old replaced by new.
+// If old is empty, it matches at the beginning of the slice
+// and after each UTF-8 sequence, yielding up to k+1 replacements
+// for a k-rune slice.
+func ReplaceAll(s, old, new []byte) []byte {
+	return Replace(s, old, new, -1)
+}
+
+// EqualFold reports whether s and t, interpreted as UTF-8 strings,
+// are equal under simple Unicode case-folding, which is a more general
+// form of case-insensitivity.
+func EqualFold(s, t []byte) bool {
+	for len(s) != 0 && len(t) != 0 {
+		// Extract first rune from each.
+		var sr, tr rune
+		if s[0] < utf8.RuneSelf {
+			sr, s = rune(s[0]), s[1:]
+		} else {
+			r, size := utf8.DecodeRune(s)
+			sr, s = r, s[size:]
+		}
+		if t[0] < utf8.RuneSelf {
+			tr, t = rune(t[0]), t[1:]
+		} else {
+			r, size := utf8.DecodeRune(t)
+			tr, t = r, t[size:]
+		}
+
+		// If they match, keep going; if not, return false.
+
+		// Easy case.
+		if tr == sr {
+			continue
+		}
+
+		// Make sr < tr to simplify what follows.
+		if tr < sr {
+			tr, sr = sr, tr
+		}
+		// Fast check for ASCII.
+		if tr < utf8.RuneSelf {
+			// ASCII only, sr/tr must be upper/lower case
+			if 'A' <= sr && sr <= 'Z' && tr == sr+'a'-'A' {
+				continue
+			}
+			return false
+		}
+
+		// General case. SimpleFold(x) returns the next equivalent rune > x
+		// or wraps around to smaller values.
+		r := unicode.SimpleFold(sr)
+		for r != sr && r < tr {
+			r = unicode.SimpleFold(r)
+		}
+		if r == tr {
+			continue
+		}
+		return false
+	}
+
+	// One string is empty. Are both?
+	return len(s) == len(t)
+}
+
+// Index returns the index of the first instance of sep in s, or -1 if sep is not present in s.
+func Index(s, sep []byte) int {
+	n := len(sep)
+	switch {
+	case n == 0:
+		return 0
+	case n == 1:
+		return IndexByte(s, sep[0])
+	case n == len(s):
+		if Equal(sep, s) {
+			return 0
+		}
+		return -1
+	case n > len(s):
+		return -1
+	case n <= bytealg.MaxLen:
+		// Use brute force when s and sep both are small
+		if len(s) <= bytealg.MaxBruteForce {
+			return bytealg.Index(s, sep)
+		}
+		c0 := sep[0]
+		c1 := sep[1]
+		i := 0
+		t := len(s) - n + 1
+		fails := 0
+		for i < t {
+			if s[i] != c0 {
+				// IndexByte is faster than bytealg.Index, so use it as long as
+				// we're not getting lots of false positives.
+				o := IndexByte(s[i+1:t], c0)
+				if o < 0 {
+					return -1
+				}
+				i += o + 1
+			}
+			if s[i+1] == c1 && Equal(s[i:i+n], sep) {
+				return i
+			}
+			fails++
+			i++
+			// Switch to bytealg.Index when IndexByte produces too many false positives.
+			if fails > bytealg.Cutover(i) {
+				r := bytealg.Index(s[i:], sep)
+				if r >= 0 {
+					return r + i
+				}
+				return -1
+			}
+		}
+		return -1
+	}
+	c0 := sep[0]
+	c1 := sep[1]
+	i := 0
+	fails := 0
+	t := len(s) - n + 1
+	for i < t {
+		if s[i] != c0 {
+			o := IndexByte(s[i+1:t], c0)
+			if o < 0 {
+				break
+			}
+			i += o + 1
+		}
+		if s[i+1] == c1 && Equal(s[i:i+n], sep) {
+			return i
+		}
+		i++
+		fails++
+		if fails >= 4+i>>4 && i < t {
+			// Give up on IndexByte, it isn't skipping ahead
+			// far enough to be better than Rabin-Karp.
+			// Experiments (using IndexPeriodic) suggest
+			// the cutover is about 16 byte skips.
+			// TODO: if large prefixes of sep are matching
+			// we should cutover at even larger average skips,
+			// because Equal becomes that much more expensive.
+			// This code does not take that effect into account.
+			j := bytealg.IndexRabinKarpBytes(s[i:], sep)
+			if j < 0 {
+				return -1
+			}
+			return i + j
+		}
+	}
+	return -1
+}
+
+// Cut slices s around the first instance of sep,
+// returning the text before and after sep.
+// The found result reports whether sep appears in s.
+// If sep does not appear in s, cut returns s, nil, false.
+//
+// Cut returns slices of the original slice s, not copies.
+func Cut(s, sep []byte) (before, after []byte, found bool) {
+	if i := Index(s, sep); i >= 0 {
+		return s[:i], s[i+len(sep):], true
+	}
+	return s, nil, false
+}
diff --git a/contrib/go/_std_1.19/src/bytes/reader.go b/contrib/go/_std_1.19/src/bytes/reader.go
new file mode 100644
index 0000000000..81c22aa029
--- /dev/null
+++ b/contrib/go/_std_1.19/src/bytes/reader.go
@@ -0,0 +1,159 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bytes
+
+import (
+	"errors"
+	"io"
+	"unicode/utf8"
+)
+
+// A Reader implements the io.Reader, io.ReaderAt, io.WriterTo, io.Seeker,
+// io.ByteScanner, and io.RuneScanner interfaces by reading from
+// a byte slice.
+// Unlike a Buffer, a Reader is read-only and supports seeking.
+// The zero value for Reader operates like a Reader of an empty slice.
+type Reader struct {
+	s        []byte
+	i        int64 // current reading index
+	prevRune int   // index of previous rune; or < 0
+}
+
+// Len returns the number of bytes of the unread portion of the
+// slice.
+func (r *Reader) Len() int {
+	if r.i >= int64(len(r.s)) {
+		return 0
+	}
+	return int(int64(len(r.s)) - r.i)
+}
+
+// Size returns the original length of the underlying byte slice.
+// Size is the number of bytes available for reading via ReadAt.
+// The result is unaffected by any method calls except Reset.
+func (r *Reader) Size() int64 { return int64(len(r.s)) }
+
+// Read implements the io.Reader interface.
+func (r *Reader) Read(b []byte) (n int, err error) {
+	if r.i >= int64(len(r.s)) {
+		return 0, io.EOF
+	}
+	r.prevRune = -1
+	n = copy(b, r.s[r.i:])
+	r.i += int64(n)
+	return
+}
+
+// ReadAt implements the io.ReaderAt interface.
+func (r *Reader) ReadAt(b []byte, off int64) (n int, err error) {
+	// cannot modify state - see io.ReaderAt
+	if off < 0 {
+		return 0, errors.New("bytes.Reader.ReadAt: negative offset")
+	}
+	if off >= int64(len(r.s)) {
+		return 0, io.EOF
+	}
+	n = copy(b, r.s[off:])
+	if n < len(b) {
+		err = io.EOF
+	}
+	return
+}
+
+// ReadByte implements the io.ByteReader interface.
+func (r *Reader) ReadByte() (byte, error) {
+	r.prevRune = -1
+	if r.i >= int64(len(r.s)) {
+		return 0, io.EOF
+	}
+	b := r.s[r.i]
+	r.i++
+	return b, nil
+}
+
+// UnreadByte complements ReadByte in implementing the io.ByteScanner interface.
+func (r *Reader) UnreadByte() error {
+	if r.i <= 0 {
+		return errors.New("bytes.Reader.UnreadByte: at beginning of slice")
+	}
+	r.prevRune = -1
+	r.i--
+	return nil
+}
+
+// ReadRune implements the io.RuneReader interface.
+func (r *Reader) ReadRune() (ch rune, size int, err error) {
+	if r.i >= int64(len(r.s)) {
+		r.prevRune = -1
+		return 0, 0, io.EOF
+	}
+	r.prevRune = int(r.i)
+	if c := r.s[r.i]; c < utf8.RuneSelf {
+		r.i++
+		return rune(c), 1, nil
+	}
+	ch, size = utf8.DecodeRune(r.s[r.i:])
+	r.i += int64(size)
+	return
+}
+
+// UnreadRune complements ReadRune in implementing the io.RuneScanner interface.
+func (r *Reader) UnreadRune() error {
+	if r.i <= 0 {
+		return errors.New("bytes.Reader.UnreadRune: at beginning of slice")
+	}
+	if r.prevRune < 0 {
+		return errors.New("bytes.Reader.UnreadRune: previous operation was not ReadRune")
+	}
+	r.i = int64(r.prevRune)
+	r.prevRune = -1
+	return nil
+}
+
+// Seek implements the io.Seeker interface.
+func (r *Reader) Seek(offset int64, whence int) (int64, error) {
+	r.prevRune = -1
+	var abs int64
+	switch whence {
+	case io.SeekStart:
+		abs = offset
+	case io.SeekCurrent:
+		abs = r.i + offset
+	case io.SeekEnd:
+		abs = int64(len(r.s)) + offset
+	default:
+		return 0, errors.New("bytes.Reader.Seek: invalid whence")
+	}
+	if abs < 0 {
+		return 0, errors.New("bytes.Reader.Seek: negative position")
+	}
+	r.i = abs
+	return abs, nil
+}
+
+// WriteTo implements the io.WriterTo interface.
+func (r *Reader) WriteTo(w io.Writer) (n int64, err error) {
+	r.prevRune = -1
+	if r.i >= int64(len(r.s)) {
+		return 0, nil
+	}
+	b := r.s[r.i:]
+	m, err := w.Write(b)
+	if m > len(b) {
+		panic("bytes.Reader.WriteTo: invalid Write count")
+	}
+	r.i += int64(m)
+	n = int64(m)
+	if m != len(b) && err == nil {
+		err = io.ErrShortWrite
+	}
+	return
+}
+
+// Reset resets the Reader to be reading from b.
+func (r *Reader) Reset(b []byte) { *r = Reader{b, 0, -1} }
+
+// NewReader returns a new Reader reading from b.
+func NewReader(b []byte) *Reader { return &Reader{b, 0, -1} }
diff --git a/contrib/go/_std_1.19/src/compress/flate/deflate.go b/contrib/go/_std_1.19/src/compress/flate/deflate.go
new file mode 100644
index 0000000000..93efd7cafb
--- /dev/null
+++ b/contrib/go/_std_1.19/src/compress/flate/deflate.go
@@ -0,0 +1,746 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package flate
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"math"
+)
+
+const (
+	NoCompression      = 0
+	BestSpeed          = 1
+	BestCompression    = 9
+	DefaultCompression = -1
+
+	// HuffmanOnly disables Lempel-Ziv match searching and only performs Huffman
+	// entropy encoding. This mode is useful in compressing data that has
+	// already been compressed with an LZ style algorithm (e.g. Snappy or LZ4)
+	// that lacks an entropy encoder. Compression gains are achieved when
+	// certain bytes in the input stream occur more frequently than others.
+	//
+	// Note that HuffmanOnly produces a compressed output that is
+	// RFC 1951 compliant. That is, any valid DEFLATE decompressor will
+	// continue to be able to decompress this output.
+	HuffmanOnly = -2
+)
+
+const (
+	logWindowSize = 15
+	windowSize    = 1 << logWindowSize
+	windowMask    = windowSize - 1
+
+	// The LZ77 step produces a sequence of literal tokens and <length, offset>
+	// pair tokens. The offset is also known as distance. The underlying wire
+	// format limits the range of lengths and offsets. For example, there are
+	// 256 legitimate lengths: those in the range [3, 258]. This package's
+	// compressor uses a higher minimum match length, enabling optimizations
+	// such as finding matches via 32-bit loads and compares.
+	baseMatchLength = 3       // The smallest match length per the RFC section 3.2.5
+	minMatchLength  = 4       // The smallest match length that the compressor actually emits
+	maxMatchLength  = 258     // The largest match length
+	baseMatchOffset = 1       // The smallest match offset
+	maxMatchOffset  = 1 << 15 // The largest match offset
+
+	// The maximum number of tokens we put into a single flate block, just to
+	// stop things from getting too large.
+	maxFlateBlockTokens = 1 << 14
+	maxStoreBlockSize   = 65535
+	hashBits            = 17 // After 17 performance degrades
+	hashSize            = 1 << hashBits
+	hashMask            = (1 << hashBits) - 1
+	maxHashOffset       = 1 << 24
+
+	skipNever = math.MaxInt32
+)
+
+type compressionLevel struct {
+	level, good, lazy, nice, chain, fastSkipHashing int
+}
+
+var levels = []compressionLevel{
+	{0, 0, 0, 0, 0, 0}, // NoCompression.
+	{1, 0, 0, 0, 0, 0}, // BestSpeed uses a custom algorithm; see deflatefast.go.
+	// For levels 2-3 we don't bother trying with lazy matches.
+	{2, 4, 0, 16, 8, 5},
+	{3, 4, 0, 32, 32, 6},
+	// Levels 4-9 use increasingly more lazy matching
+	// and increasingly stringent conditions for "good enough".
+	{4, 4, 4, 16, 16, skipNever},
+	{5, 8, 16, 32, 32, skipNever},
+	{6, 8, 16, 128, 128, skipNever},
+	{7, 8, 32, 128, 256, skipNever},
+	{8, 32, 128, 258, 1024, skipNever},
+	{9, 32, 258, 258, 4096, skipNever},
+}
+
+type compressor struct {
+	compressionLevel
+
+	w          *huffmanBitWriter
+	bulkHasher func([]byte, []uint32)
+
+	// compression algorithm
+	fill      func(*compressor, []byte) int // copy data to window
+	step      func(*compressor)             // process window
+	sync      bool                          // requesting flush
+	bestSpeed *deflateFast                  // Encoder for BestSpeed
+
+	// Input hash chains
+	// hashHead[hashValue] contains the largest inputIndex with the specified hash value
+	// If hashHead[hashValue] is within the current window, then
+	// hashPrev[hashHead[hashValue] & windowMask] contains the previous index
+	// with the same hash value.
+	chainHead  int
+	hashHead   [hashSize]uint32
+	hashPrev   [windowSize]uint32
+	hashOffset int
+
+	// input window: unprocessed data is window[index:windowEnd]
+	index         int
+	window        []byte
+	windowEnd     int
+	blockStart    int  // window index where current tokens start
+	byteAvailable bool // if true, still need to process window[index-1].
+
+	// queued output tokens
+	tokens []token
+
+	// deflate state
+	length         int
+	offset         int
+	maxInsertIndex int
+	err            error
+
+	// hashMatch must be able to contain hashes for the maximum match length.
+	hashMatch [maxMatchLength - 1]uint32
+}
+
+func (d *compressor) fillDeflate(b []byte) int {
+	if d.index >= 2*windowSize-(minMatchLength+maxMatchLength) {
+		// shift the window by windowSize
+		copy(d.window, d.window[windowSize:2*windowSize])
+		d.index -= windowSize
+		d.windowEnd -= windowSize
+		if d.blockStart >= windowSize {
+			d.blockStart -= windowSize
+		} else {
+			d.blockStart = math.MaxInt32
+		}
+		d.hashOffset += windowSize
+		if d.hashOffset > maxHashOffset {
+			delta := d.hashOffset - 1
+			d.hashOffset -= delta
+			d.chainHead -= delta
+
+			// Iterate over slices instead of arrays to avoid copying
+			// the entire table onto the stack (Issue #18625).
+			for i, v := range d.hashPrev[:] {
+				if int(v) > delta {
+					d.hashPrev[i] = uint32(int(v) - delta)
+				} else {
+					d.hashPrev[i] = 0
+				}
+			}
+			for i, v := range d.hashHead[:] {
+				if int(v) > delta {
+					d.hashHead[i] = uint32(int(v) - delta)
+				} else {
+					d.hashHead[i] = 0
+				}
+			}
+		}
+	}
+	n := copy(d.window[d.windowEnd:], b)
+	d.windowEnd += n
+	return n
+}
+
+func (d *compressor) writeBlock(tokens []token, index int) error {
+	if index > 0 {
+		var window []byte
+		if d.blockStart <= index {
+			window = d.window[d.blockStart:index]
+		}
+		d.blockStart = index
+		d.w.writeBlock(tokens, false, window)
+		return d.w.err
+	}
+	return nil
+}
+
+// fillWindow will fill the current window with the supplied
+// dictionary and calculate all hashes.
+// This is much faster than doing a full encode.
+// Should only be used after a reset.
+func (d *compressor) fillWindow(b []byte) {
+	// Do not fill window if we are in store-only mode.
+	if d.compressionLevel.level < 2 {
+		return
+	}
+	if d.index != 0 || d.windowEnd != 0 {
+		panic("internal error: fillWindow called with stale data")
+	}
+
+	// If we are given too much, cut it.
+	if len(b) > windowSize {
+		b = b[len(b)-windowSize:]
+	}
+	// Add all to window.
+	n := copy(d.window, b)
+
+	// Calculate 256 hashes at the time (more L1 cache hits)
+	loops := (n + 256 - minMatchLength) / 256
+	for j := 0; j < loops; j++ {
+		index := j * 256
+		end := index + 256 + minMatchLength - 1
+		if end > n {
+			end = n
+		}
+		toCheck := d.window[index:end]
+		dstSize := len(toCheck) - minMatchLength + 1
+
+		if dstSize <= 0 {
+			continue
+		}
+
+		dst := d.hashMatch[:dstSize]
+		d.bulkHasher(toCheck, dst)
+		for i, val := range dst {
+			di := i + index
+			hh := &d.hashHead[val&hashMask]
+			// Get previous value with the same hash.
+			// Our chain should point to the previous value.
+			d.hashPrev[di&windowMask] = *hh
+			// Set the head of the hash chain to us.
+			*hh = uint32(di + d.hashOffset)
+		}
+	}
+	// Update window information.
+	d.windowEnd = n
+	d.index = n
+}
+
+// Try to find a match starting at index whose length is greater than prevSize.
+// We only look at chainCount possibilities before giving up.
+func (d *compressor) findMatch(pos int, prevHead int, prevLength int, lookahead int) (length, offset int, ok bool) {
+	minMatchLook := maxMatchLength
+	if lookahead < minMatchLook {
+		minMatchLook = lookahead
+	}
+
+	win := d.window[0 : pos+minMatchLook]
+
+	// We quit when we get a match that's at least nice long
+	nice := len(win) - pos
+	if d.nice < nice {
+		nice = d.nice
+	}
+
+	// If we've got a match that's good enough, only look in 1/4 the chain.
+	tries := d.chain
+	length = prevLength
+	if length >= d.good {
+		tries >>= 2
+	}
+
+	wEnd := win[pos+length]
+	wPos := win[pos:]
+	minIndex := pos - windowSize
+
+	for i := prevHead; tries > 0; tries-- {
+		if wEnd == win[i+length] {
+			n := matchLen(win[i:], wPos, minMatchLook)
+
+			if n > length && (n > minMatchLength || pos-i <= 4096) {
+				length = n
+				offset = pos - i
+				ok = true
+				if n >= nice {
+					// The match is good enough that we don't try to find a better one.
+					break
+				}
+				wEnd = win[pos+n]
+			}
+		}
+		if i == minIndex {
+			// hashPrev[i & windowMask] has already been overwritten, so stop now.
+			break
+		}
+		i = int(d.hashPrev[i&windowMask]) - d.hashOffset
+		if i < minIndex || i < 0 {
+			break
+		}
+	}
+	return
+}
+
+func (d *compressor) writeStoredBlock(buf []byte) error {
+	if d.w.writeStoredHeader(len(buf), false); d.w.err != nil {
+		return d.w.err
+	}
+	d.w.writeBytes(buf)
+	return d.w.err
+}
+
+const hashmul = 0x1e35a7bd
+
+// hash4 returns a hash representation of the first 4 bytes
+// of the supplied slice.
+// The caller must ensure that len(b) >= 4.
+func hash4(b []byte) uint32 {
+	return ((uint32(b[3]) | uint32(b[2])<<8 | uint32(b[1])<<16 | uint32(b[0])<<24) * hashmul) >> (32 - hashBits)
+}
+
+// bulkHash4 will compute hashes using the same
+// algorithm as hash4
+func bulkHash4(b []byte, dst []uint32) {
+	if len(b) < minMatchLength {
+		return
+	}
+	hb := uint32(b[3]) | uint32(b[2])<<8 | uint32(b[1])<<16 | uint32(b[0])<<24
+	dst[0] = (hb * hashmul) >> (32 - hashBits)
+	end := len(b) - minMatchLength + 1
+	for i := 1; i < end; i++ {
+		hb = (hb << 8) | uint32(b[i+3])
+		dst[i] = (hb * hashmul) >> (32 - hashBits)
+	}
+}
+
+// matchLen returns the number of matching bytes in a and b
+// up to length 'max'. Both slices must be at least 'max'
+// bytes in size.
+func matchLen(a, b []byte, max int) int {
+	a = a[:max]
+	b = b[:len(a)]
+	for i, av := range a {
+		if b[i] != av {
+			return i
+		}
+	}
+	return max
+}
+
+// encSpeed will compress and store the currently added data,
+// if enough has been accumulated or we at the end of the stream.
+// Any error that occurred will be in d.err
+func (d *compressor) encSpeed() {
+	// We only compress if we have maxStoreBlockSize.
+	if d.windowEnd < maxStoreBlockSize {
+		if !d.sync {
+			return
+		}
+
+		// Handle small sizes.
+		if d.windowEnd < 128 {
+			switch {
+			case d.windowEnd == 0:
+				return
+			case d.windowEnd <= 16:
+				d.err = d.writeStoredBlock(d.window[:d.windowEnd])
+			default:
+				d.w.writeBlockHuff(false, d.window[:d.windowEnd])
+				d.err = d.w.err
+			}
+			d.windowEnd = 0
+			d.bestSpeed.reset()
+			return
+		}
+
+	}
+	// Encode the block.
+	d.tokens = d.bestSpeed.encode(d.tokens[:0], d.window[:d.windowEnd])
+
+	// If we removed less than 1/16th, Huffman compress the block.
+	if len(d.tokens) > d.windowEnd-(d.windowEnd>>4) {
+		d.w.writeBlockHuff(false, d.window[:d.windowEnd])
+	} else {
+		d.w.writeBlockDynamic(d.tokens, false, d.window[:d.windowEnd])
+	}
+	d.err = d.w.err
+	d.windowEnd = 0
+}
+
+func (d *compressor) initDeflate() {
+	d.window = make([]byte, 2*windowSize)
+	d.hashOffset = 1
+	d.tokens = make([]token, 0, maxFlateBlockTokens+1)
+	d.length = minMatchLength - 1
+	d.offset = 0
+	d.byteAvailable = false
+	d.index = 0
+	d.chainHead = -1
+	d.bulkHasher = bulkHash4
+}
+
+func (d *compressor) deflate() {
+	if d.windowEnd-d.index < minMatchLength+maxMatchLength && !d.sync {
+		return
+	}
+
+	d.maxInsertIndex = d.windowEnd - (minMatchLength - 1)
+
+Loop:
+	for {
+		if d.index > d.windowEnd {
+			panic("index > windowEnd")
+		}
+		lookahead := d.windowEnd - d.index
+		if lookahead < minMatchLength+maxMatchLength {
+			if !d.sync {
+				break Loop
+			}
+			if d.index > d.windowEnd {
+				panic("index > windowEnd")
+			}
+			if lookahead == 0 {
+				// Flush current output block if any.
+				if d.byteAvailable {
+					// There is still one pending token that needs to be flushed
+					d.tokens = append(d.tokens, literalToken(uint32(d.window[d.index-1])))
+					d.byteAvailable = false
+				}
+				if len(d.tokens) > 0 {
+					if d.err = d.writeBlock(d.tokens, d.index); d.err != nil {
+						return
+					}
+					d.tokens = d.tokens[:0]
+				}
+				break Loop
+			}
+		}
+		if d.index < d.maxInsertIndex {
+			// Update the hash
+			hash := hash4(d.window[d.index : d.index+minMatchLength])
+			hh := &d.hashHead[hash&hashMask]
+			d.chainHead = int(*hh)
+			d.hashPrev[d.index&windowMask] = uint32(d.chainHead)
+			*hh = uint32(d.index + d.hashOffset)
+		}
+		prevLength := d.length
+		prevOffset := d.offset
+		d.length = minMatchLength - 1
+		d.offset = 0
+		minIndex := d.index - windowSize
+		if minIndex < 0 {
+			minIndex = 0
+		}
+
+		if d.chainHead-d.hashOffset >= minIndex &&
+			(d.fastSkipHashing != skipNever && lookahead > minMatchLength-1 ||
+				d.fastSkipHashing == skipNever && lookahead > prevLength && prevLength < d.lazy) {
+			if newLength, newOffset, ok := d.findMatch(d.index, d.chainHead-d.hashOffset, minMatchLength-1, lookahead); ok {
+				d.length = newLength
+				d.offset = newOffset
+			}
+		}
+		if d.fastSkipHashing != skipNever && d.length >= minMatchLength ||
+			d.fastSkipHashing == skipNever && prevLength >= minMatchLength && d.length <= prevLength {
+			// There was a match at the previous step, and the current match is
+			// not better. Output the previous match.
+			if d.fastSkipHashing != skipNever {
+				d.tokens = append(d.tokens, matchToken(uint32(d.length-baseMatchLength), uint32(d.offset-baseMatchOffset)))
+			} else {
+				d.tokens = append(d.tokens, matchToken(uint32(prevLength-baseMatchLength), uint32(prevOffset-baseMatchOffset)))
+			}
+			// Insert in the hash table all strings up to the end of the match.
+			// index and index-1 are already inserted. If there is not enough
+			// lookahead, the last two strings are not inserted into the hash
+			// table.
+			if d.length <= d.fastSkipHashing {
+				var newIndex int
+				if d.fastSkipHashing != skipNever {
+					newIndex = d.index + d.length
+				} else {
+					newIndex = d.index + prevLength - 1
+				}
+				index := d.index
+				for index++; index < newIndex; index++ {
+					if index < d.maxInsertIndex {
+						hash := hash4(d.window[index : index+minMatchLength])
+						// Get previous value with the same hash.
+						// Our chain should point to the previous value.
+						hh := &d.hashHead[hash&hashMask]
+						d.hashPrev[index&windowMask] = *hh
+						// Set the head of the hash chain to us.
+						*hh = uint32(index + d.hashOffset)
+					}
+				}
+				d.index = index
+
+				if d.fastSkipHashing == skipNever {
+					d.byteAvailable = false
+					d.length = minMatchLength - 1
+				}
+			} else {
+				// For matches this long, we don't bother inserting each individual
+				// item into the table.
+				d.index += d.length
+			}
+			if len(d.tokens) == maxFlateBlockTokens {
+				// The block includes the current character
+				if d.err = d.writeBlock(d.tokens, d.index); d.err != nil {
+					return
+				}
+				d.tokens = d.tokens[:0]
+			}
+		} else {
+			if d.fastSkipHashing != skipNever || d.byteAvailable {
+				i := d.index - 1
+				if d.fastSkipHashing != skipNever {
+					i = d.index
+				}
+				d.tokens = append(d.tokens, literalToken(uint32(d.window[i])))
+				if len(d.tokens) == maxFlateBlockTokens {
+					if d.err = d.writeBlock(d.tokens, i+1); d.err != nil {
+						return
+					}
+					d.tokens = d.tokens[:0]
+				}
+			}
+			d.index++
+			if d.fastSkipHashing == skipNever {
+				d.byteAvailable = true
+			}
+		}
+	}
+}
+
+func (d *compressor) fillStore(b []byte) int {
+	n := copy(d.window[d.windowEnd:], b)
+	d.windowEnd += n
+	return n
+}
+
+func (d *compressor) store() {
+	if d.windowEnd > 0 && (d.windowEnd == maxStoreBlockSize || d.sync) {
+		d.err = d.writeStoredBlock(d.window[:d.windowEnd])
+		d.windowEnd = 0
+	}
+}
+
+// storeHuff compresses and stores the currently added data
+// when the d.window is full or we are at the end of the stream.
+// Any error that occurred will be in d.err
+func (d *compressor) storeHuff() {
+	if d.windowEnd < len(d.window) && !d.sync || d.windowEnd == 0 {
+		return
+	}
+	d.w.writeBlockHuff(false, d.window[:d.windowEnd])
+	d.err = d.w.err
+	d.windowEnd = 0
+}
+
+func (d *compressor) write(b []byte) (n int, err error) {
+	if d.err != nil {
+		return 0, d.err
+	}
+	n = len(b)
+	for len(b) > 0 {
+		d.step(d)
+		b = b[d.fill(d, b):]
+		if d.err != nil {
+			return 0, d.err
+		}
+	}
+	return n, nil
+}
+
+func (d *compressor) syncFlush() error {
+	if d.err != nil {
+		return d.err
+	}
+	d.sync = true
+	d.step(d)
+	if d.err == nil {
+		d.w.writeStoredHeader(0, false)
+		d.w.flush()
+		d.err = d.w.err
+	}
+	d.sync = false
+	return d.err
+}
+
+func (d *compressor) init(w io.Writer, level int) (err error) {
+	d.w = newHuffmanBitWriter(w)
+
+	switch {
+	case level == NoCompression:
+		d.window = make([]byte, maxStoreBlockSize)
+		d.fill = (*compressor).fillStore
+		d.step = (*compressor).store
+	case level == HuffmanOnly:
+		d.window = make([]byte, maxStoreBlockSize)
+		d.fill = (*compressor).fillStore
+		d.step = (*compressor).storeHuff
+	case level == BestSpeed:
+		d.compressionLevel = levels[level]
+		d.window = make([]byte, maxStoreBlockSize)
+		d.fill = (*compressor).fillStore
+		d.step = (*compressor).encSpeed
+		d.bestSpeed = newDeflateFast()
+		d.tokens = make([]token, maxStoreBlockSize)
+	case level == DefaultCompression:
+		level = 6
+		fallthrough
+	case 2 <= level && level <= 9:
+		d.compressionLevel = levels[level]
+		d.initDeflate()
+		d.fill = (*compressor).fillDeflate
+		d.step = (*compressor).deflate
+	default:
+		return fmt.Errorf("flate: invalid compression level %d: want value in range [-2, 9]", level)
+	}
+	return nil
+}
+
+func (d *compressor) reset(w io.Writer) {
+	d.w.reset(w)
+	d.sync = false
+	d.err = nil
+	switch d.compressionLevel.level {
+	case NoCompression:
+		d.windowEnd = 0
+	case BestSpeed:
+		d.windowEnd = 0
+		d.tokens = d.tokens[:0]
+		d.bestSpeed.reset()
+	default:
+		d.chainHead = -1
+		for i := range d.hashHead {
+			d.hashHead[i] = 0
+		}
+		for i := range d.hashPrev {
+			d.hashPrev[i] = 0
+		}
+		d.hashOffset = 1
+		d.index, d.windowEnd = 0, 0
+		d.blockStart, d.byteAvailable = 0, false
+		d.tokens = d.tokens[:0]
+		d.length = minMatchLength - 1
+		d.offset = 0
+		d.maxInsertIndex = 0
+	}
+}
+
+func (d *compressor) close() error {
+	if d.err == errWriterClosed {
+		return nil
+	}
+	if d.err != nil {
+		return d.err
+	}
+	d.sync = true
+	d.step(d)
+	if d.err != nil {
+		return d.err
+	}
+	if d.w.writeStoredHeader(0, true); d.w.err != nil {
+		return d.w.err
+	}
+	d.w.flush()
+	if d.w.err != nil {
+		return d.w.err
+	}
+	d.err = errWriterClosed
+	return nil
+}
+
+// NewWriter returns a new Writer compressing data at the given level.
+// Following zlib, levels range from 1 (BestSpeed) to 9 (BestCompression);
+// higher levels typically run slower but compress more. Level 0
+// (NoCompression) does not attempt any compression; it only adds the
+// necessary DEFLATE framing.
+// Level -1 (DefaultCompression) uses the default compression level.
+// Level -2 (HuffmanOnly) will use Huffman compression only, giving
+// a very fast compression for all types of input, but sacrificing considerable
+// compression efficiency.
+//
+// If level is in the range [-2, 9] then the error returned will be nil.
+// Otherwise the error returned will be non-nil.
+func NewWriter(w io.Writer, level int) (*Writer, error) {
+	var dw Writer
+	if err := dw.d.init(w, level); err != nil {
+		return nil, err
+	}
+	return &dw, nil
+}
+
+// NewWriterDict is like NewWriter but initializes the new
+// Writer with a preset dictionary. The returned Writer behaves
+// as if the dictionary had been written to it without producing
+// any compressed output. The compressed data written to w
+// can only be decompressed by a Reader initialized with the
+// same dictionary.
+func NewWriterDict(w io.Writer, level int, dict []byte) (*Writer, error) {
+	dw := &dictWriter{w}
+	zw, err := NewWriter(dw, level)
+	if err != nil {
+		return nil, err
+	}
+	zw.d.fillWindow(dict)
+	zw.dict = append(zw.dict, dict...) // duplicate dictionary for Reset method.
+	return zw, err
+}
+
+type dictWriter struct {
+	w io.Writer
+}
+
+func (w *dictWriter) Write(b []byte) (n int, err error) {
+	return w.w.Write(b)
+}
+
+var errWriterClosed = errors.New("flate: closed writer")
+
+// A Writer takes data written to it and writes the compressed
+// form of that data to an underlying writer (see NewWriter).
+type Writer struct {
+	d    compressor
+	dict []byte
+}
+
+// Write writes data to w, which will eventually write the
+// compressed form of data to its underlying writer.
+func (w *Writer) Write(data []byte) (n int, err error) {
+	return w.d.write(data)
+}
+
+// Flush flushes any pending data to the underlying writer.
+// It is useful mainly in compressed network protocols, to ensure that
+// a remote reader has enough data to reconstruct a packet.
+// Flush does not return until the data has been written.
+// Calling Flush when there is no pending data still causes the Writer
+// to emit a sync marker of at least 4 bytes.
+// If the underlying writer returns an error, Flush returns that error.
+//
+// In the terminology of the zlib library, Flush is equivalent to Z_SYNC_FLUSH.
+func (w *Writer) Flush() error {
+	// For more about flushing:
+	// https://www.bolet.org/~pornin/deflate-flush.html
+	return w.d.syncFlush()
+}
+
+// Close flushes and closes the writer.
+func (w *Writer) Close() error {
+	return w.d.close()
+}
+
+// Reset discards the writer's state and makes it equivalent to
+// the result of NewWriter or NewWriterDict called with dst
+// and w's level and dictionary.
+func (w *Writer) Reset(dst io.Writer) {
+	if dw, ok := w.d.w.writer.(*dictWriter); ok {
+		// w was created with NewWriterDict
+		dw.w = dst
+		w.d.reset(dw)
+		w.d.fillWindow(w.dict)
+	} else {
+		// w was created with NewWriter
+		w.d.reset(dst)
+	}
+}
diff --git a/contrib/go/_std_1.18/src/compress/flate/deflatefast.go b/contrib/go/_std_1.19/src/compress/flate/deflatefast.go
index 6aa439f13d..6aa439f13d 100644
--- a/contrib/go/_std_1.18/src/compress/flate/deflatefast.go
+++ b/contrib/go/_std_1.19/src/compress/flate/deflatefast.go
diff --git a/contrib/go/_std_1.19/src/compress/flate/dict_decoder.go b/contrib/go/_std_1.19/src/compress/flate/dict_decoder.go
new file mode 100644
index 0000000000..d2c19040f5
--- /dev/null
+++ b/contrib/go/_std_1.19/src/compress/flate/dict_decoder.go
@@ -0,0 +1,182 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package flate
+
+// dictDecoder implements the LZ77 sliding dictionary as used in decompression.
+// LZ77 decompresses data through sequences of two forms of commands:
+//
+//   - Literal insertions: Runs of one or more symbols are inserted into the data
+//     stream as is. This is accomplished through the writeByte method for a
+//     single symbol, or combinations of writeSlice/writeMark for multiple symbols.
+//     Any valid stream must start with a literal insertion if no preset dictionary
+//     is used.
+//
+//   - Backward copies: Runs of one or more symbols are copied from previously
+//     emitted data. Backward copies come as the tuple (dist, length) where dist
+//     determines how far back in the stream to copy from and length determines how
+//     many bytes to copy. Note that it is valid for the length to be greater than
+//     the distance. Since LZ77 uses forward copies, that situation is used to
+//     perform a form of run-length encoding on repeated runs of symbols.
+//     The writeCopy and tryWriteCopy are used to implement this command.
+//
+// For performance reasons, this implementation performs little to no sanity
+// checks about the arguments. As such, the invariants documented for each
+// method call must be respected.
+type dictDecoder struct {
+	hist []byte // Sliding window history
+
+	// Invariant: 0 <= rdPos <= wrPos <= len(hist)
+	wrPos int  // Current output position in buffer
+	rdPos int  // Have emitted hist[:rdPos] already
+	full  bool // Has a full window length been written yet?
+}
+
+// init initializes dictDecoder to have a sliding window dictionary of the given
+// size. If a preset dict is provided, it will initialize the dictionary with
+// the contents of dict.
+func (dd *dictDecoder) init(size int, dict []byte) {
+	*dd = dictDecoder{hist: dd.hist}
+
+	if cap(dd.hist) < size {
+		dd.hist = make([]byte, size)
+	}
+	dd.hist = dd.hist[:size]
+
+	if len(dict) > len(dd.hist) {
+		dict = dict[len(dict)-len(dd.hist):]
+	}
+	dd.wrPos = copy(dd.hist, dict)
+	if dd.wrPos == len(dd.hist) {
+		dd.wrPos = 0
+		dd.full = true
+	}
+	dd.rdPos = dd.wrPos
+}
+
+// histSize reports the total amount of historical data in the dictionary.
+func (dd *dictDecoder) histSize() int {
+	if dd.full {
+		return len(dd.hist)
+	}
+	return dd.wrPos
+}
+
+// availRead reports the number of bytes that can be flushed by readFlush.
+func (dd *dictDecoder) availRead() int {
+	return dd.wrPos - dd.rdPos
+}
+
+// availWrite reports the available amount of output buffer space.
+func (dd *dictDecoder) availWrite() int {
+	return len(dd.hist) - dd.wrPos
+}
+
+// writeSlice returns a slice of the available buffer to write data to.
+//
+// This invariant will be kept: len(s) <= availWrite()
+func (dd *dictDecoder) writeSlice() []byte {
+	return dd.hist[dd.wrPos:]
+}
+
+// writeMark advances the writer pointer by cnt.
+//
+// This invariant must be kept: 0 <= cnt <= availWrite()
+func (dd *dictDecoder) writeMark(cnt int) {
+	dd.wrPos += cnt
+}
+
+// writeByte writes a single byte to the dictionary.
+//
+// This invariant must be kept: 0 < availWrite()
+func (dd *dictDecoder) writeByte(c byte) {
+	dd.hist[dd.wrPos] = c
+	dd.wrPos++
+}
+
+// writeCopy copies a string at a given (dist, length) to the output.
+// This returns the number of bytes copied and may be less than the requested
+// length if the available space in the output buffer is too small.
+//
+// This invariant must be kept: 0 < dist <= histSize()
+func (dd *dictDecoder) writeCopy(dist, length int) int {
+	dstBase := dd.wrPos
+	dstPos := dstBase
+	srcPos := dstPos - dist
+	endPos := dstPos + length
+	if endPos > len(dd.hist) {
+		endPos = len(dd.hist)
+	}
+
+	// Copy non-overlapping section after destination position.
+	//
+	// This section is non-overlapping in that the copy length for this section
+	// is always less than or equal to the backwards distance. This can occur
+	// if a distance refers to data that wraps-around in the buffer.
+	// Thus, a backwards copy is performed here; that is, the exact bytes in
+	// the source prior to the copy is placed in the destination.
+	if srcPos < 0 {
+		srcPos += len(dd.hist)
+		dstPos += copy(dd.hist[dstPos:endPos], dd.hist[srcPos:])
+		srcPos = 0
+	}
+
+	// Copy possibly overlapping section before destination position.
+	//
+	// This section can overlap if the copy length for this section is larger
+	// than the backwards distance. This is allowed by LZ77 so that repeated
+	// strings can be succinctly represented using (dist, length) pairs.
+	// Thus, a forwards copy is performed here; that is, the bytes copied is
+	// possibly dependent on the resulting bytes in the destination as the copy
+	// progresses along. This is functionally equivalent to the following:
+	//
+	//	for i := 0; i < endPos-dstPos; i++ {
+	//		dd.hist[dstPos+i] = dd.hist[srcPos+i]
+	//	}
+	//	dstPos = endPos
+	//
+	for dstPos < endPos {
+		dstPos += copy(dd.hist[dstPos:endPos], dd.hist[srcPos:dstPos])
+	}
+
+	dd.wrPos = dstPos
+	return dstPos - dstBase
+}
+
+// tryWriteCopy tries to copy a string at a given (distance, length) to the
+// output. This specialized version is optimized for short distances.
+//
+// This method is designed to be inlined for performance reasons.
+//
+// This invariant must be kept: 0 < dist <= histSize()
+func (dd *dictDecoder) tryWriteCopy(dist, length int) int {
+	dstPos := dd.wrPos
+	endPos := dstPos + length
+	if dstPos < dist || endPos > len(dd.hist) {
+		return 0
+	}
+	dstBase := dstPos
+	srcPos := dstPos - dist
+
+	// Copy possibly overlapping section before destination position.
+	for dstPos < endPos {
+		dstPos += copy(dd.hist[dstPos:endPos], dd.hist[srcPos:dstPos])
+	}
+
+	dd.wrPos = dstPos
+	return dstPos - dstBase
+}
+
+// readFlush returns a slice of the historical buffer that is ready to be
+// emitted to the user. The data returned by readFlush must be fully consumed
+// before calling any other dictDecoder methods.
+func (dd *dictDecoder) readFlush() []byte {
+	toRead := dd.hist[dd.rdPos:dd.wrPos]
+	dd.rdPos = dd.wrPos
+	if dd.wrPos == len(dd.hist) {
+		dd.wrPos, dd.rdPos = 0, 0
+		dd.full = true
+	}
+	return toRead
+}
diff --git a/contrib/go/_std_1.19/src/compress/flate/huffman_bit_writer.go b/contrib/go/_std_1.19/src/compress/flate/huffman_bit_writer.go
new file mode 100644
index 0000000000..6a4e48e9ee
--- /dev/null
+++ b/contrib/go/_std_1.19/src/compress/flate/huffman_bit_writer.go
@@ -0,0 +1,704 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package flate
+
+import (
+	"io"
+)
+
+const (
+	// The largest offset code.
+	offsetCodeCount = 30
+
+	// The special code used to mark the end of a block.
+	endBlockMarker = 256
+
+	// The first length code.
+	lengthCodesStart = 257
+
+	// The number of codegen codes.
+	codegenCodeCount = 19
+	badCode          = 255
+
+	// bufferFlushSize indicates the buffer size
+	// after which bytes are flushed to the writer.
+	// Should preferably be a multiple of 6, since
+	// we accumulate 6 bytes between writes to the buffer.
+	bufferFlushSize = 240
+
+	// bufferSize is the actual output byte buffer size.
+	// It must have additional headroom for a flush
+	// which can contain up to 8 bytes.
+	bufferSize = bufferFlushSize + 8
+)
+
+// The number of extra bits needed by length code X - LENGTH_CODES_START.
+var lengthExtraBits = []int8{
+	/* 257 */ 0, 0, 0,
+	/* 260 */ 0, 0, 0, 0, 0, 1, 1, 1, 1, 2,
+	/* 270 */ 2, 2, 2, 3, 3, 3, 3, 4, 4, 4,
+	/* 280 */ 4, 5, 5, 5, 5, 0,
+}
+
+// The length indicated by length code X - LENGTH_CODES_START.
+var lengthBase = []uint32{
+	0, 1, 2, 3, 4, 5, 6, 7, 8, 10,
+	12, 14, 16, 20, 24, 28, 32, 40, 48, 56,
+	64, 80, 96, 112, 128, 160, 192, 224, 255,
+}
+
+// offset code word extra bits.
+var offsetExtraBits = []int8{
+	0, 0, 0, 0, 1, 1, 2, 2, 3, 3,
+	4, 4, 5, 5, 6, 6, 7, 7, 8, 8,
+	9, 9, 10, 10, 11, 11, 12, 12, 13, 13,
+}
+
+var offsetBase = []uint32{
+	0x000000, 0x000001, 0x000002, 0x000003, 0x000004,
+	0x000006, 0x000008, 0x00000c, 0x000010, 0x000018,
+	0x000020, 0x000030, 0x000040, 0x000060, 0x000080,
+	0x0000c0, 0x000100, 0x000180, 0x000200, 0x000300,
+	0x000400, 0x000600, 0x000800, 0x000c00, 0x001000,
+	0x001800, 0x002000, 0x003000, 0x004000, 0x006000,
+}
+
+// The odd order in which the codegen code sizes are written.
+var codegenOrder = []uint32{16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}
+
+type huffmanBitWriter struct {
+	// writer is the underlying writer.
+	// Do not use it directly; use the write method, which ensures
+	// that Write errors are sticky.
+	writer io.Writer
+
+	// Data waiting to be written is bytes[0:nbytes]
+	// and then the low nbits of bits.  Data is always written
+	// sequentially into the bytes array.
+	bits            uint64
+	nbits           uint
+	bytes           [bufferSize]byte
+	codegenFreq     [codegenCodeCount]int32
+	nbytes          int
+	literalFreq     []int32
+	offsetFreq      []int32
+	codegen         []uint8
+	literalEncoding *huffmanEncoder
+	offsetEncoding  *huffmanEncoder
+	codegenEncoding *huffmanEncoder
+	err             error
+}
+
+func newHuffmanBitWriter(w io.Writer) *huffmanBitWriter {
+	return &huffmanBitWriter{
+		writer:          w,
+		literalFreq:     make([]int32, maxNumLit),
+		offsetFreq:      make([]int32, offsetCodeCount),
+		codegen:         make([]uint8, maxNumLit+offsetCodeCount+1),
+		literalEncoding: newHuffmanEncoder(maxNumLit),
+		codegenEncoding: newHuffmanEncoder(codegenCodeCount),
+		offsetEncoding:  newHuffmanEncoder(offsetCodeCount),
+	}
+}
+
+func (w *huffmanBitWriter) reset(writer io.Writer) {
+	w.writer = writer
+	w.bits, w.nbits, w.nbytes, w.err = 0, 0, 0, nil
+}
+
+func (w *huffmanBitWriter) flush() {
+	if w.err != nil {
+		w.nbits = 0
+		return
+	}
+	n := w.nbytes
+	for w.nbits != 0 {
+		w.bytes[n] = byte(w.bits)
+		w.bits >>= 8
+		if w.nbits > 8 { // Avoid underflow
+			w.nbits -= 8
+		} else {
+			w.nbits = 0
+		}
+		n++
+	}
+	w.bits = 0
+	w.write(w.bytes[:n])
+	w.nbytes = 0
+}
+
+func (w *huffmanBitWriter) write(b []byte) {
+	if w.err != nil {
+		return
+	}
+	_, w.err = w.writer.Write(b)
+}
+
+func (w *huffmanBitWriter) writeBits(b int32, nb uint) {
+	if w.err != nil {
+		return
+	}
+	w.bits |= uint64(b) << w.nbits
+	w.nbits += nb
+	if w.nbits >= 48 {
+		bits := w.bits
+		w.bits >>= 48
+		w.nbits -= 48
+		n := w.nbytes
+		bytes := w.bytes[n : n+6]
+		bytes[0] = byte(bits)
+		bytes[1] = byte(bits >> 8)
+		bytes[2] = byte(bits >> 16)
+		bytes[3] = byte(bits >> 24)
+		bytes[4] = byte(bits >> 32)
+		bytes[5] = byte(bits >> 40)
+		n += 6
+		if n >= bufferFlushSize {
+			w.write(w.bytes[:n])
+			n = 0
+		}
+		w.nbytes = n
+	}
+}
+
+func (w *huffmanBitWriter) writeBytes(bytes []byte) {
+	if w.err != nil {
+		return
+	}
+	n := w.nbytes
+	if w.nbits&7 != 0 {
+		w.err = InternalError("writeBytes with unfinished bits")
+		return
+	}
+	for w.nbits != 0 {
+		w.bytes[n] = byte(w.bits)
+		w.bits >>= 8
+		w.nbits -= 8
+		n++
+	}
+	if n != 0 {
+		w.write(w.bytes[:n])
+	}
+	w.nbytes = 0
+	w.write(bytes)
+}
+
+// RFC 1951 3.2.7 specifies a special run-length encoding for specifying
+// the literal and offset lengths arrays (which are concatenated into a single
+// array).  This method generates that run-length encoding.
+//
+// The result is written into the codegen array, and the frequencies
+// of each code is written into the codegenFreq array.
+// Codes 0-15 are single byte codes. Codes 16-18 are followed by additional
+// information. Code badCode is an end marker
+//
+//	numLiterals      The number of literals in literalEncoding
+//	numOffsets       The number of offsets in offsetEncoding
+//	litenc, offenc   The literal and offset encoder to use
+func (w *huffmanBitWriter) generateCodegen(numLiterals int, numOffsets int, litEnc, offEnc *huffmanEncoder) {
+	for i := range w.codegenFreq {
+		w.codegenFreq[i] = 0
+	}
+	// Note that we are using codegen both as a temporary variable for holding
+	// a copy of the frequencies, and as the place where we put the result.
+	// This is fine because the output is always shorter than the input used
+	// so far.
+	codegen := w.codegen // cache
+	// Copy the concatenated code sizes to codegen. Put a marker at the end.
+	cgnl := codegen[:numLiterals]
+	for i := range cgnl {
+		cgnl[i] = uint8(litEnc.codes[i].len)
+	}
+
+	cgnl = codegen[numLiterals : numLiterals+numOffsets]
+	for i := range cgnl {
+		cgnl[i] = uint8(offEnc.codes[i].len)
+	}
+	codegen[numLiterals+numOffsets] = badCode
+
+	size := codegen[0]
+	count := 1
+	outIndex := 0
+	for inIndex := 1; size != badCode; inIndex++ {
+		// INVARIANT: We have seen "count" copies of size that have not yet
+		// had output generated for them.
+		nextSize := codegen[inIndex]
+		if nextSize == size {
+			count++
+			continue
+		}
+		// We need to generate codegen indicating "count" of size.
+		if size != 0 {
+			codegen[outIndex] = size
+			outIndex++
+			w.codegenFreq[size]++
+			count--
+			for count >= 3 {
+				n := 6
+				if n > count {
+					n = count
+				}
+				codegen[outIndex] = 16
+				outIndex++
+				codegen[outIndex] = uint8(n - 3)
+				outIndex++
+				w.codegenFreq[16]++
+				count -= n
+			}
+		} else {
+			for count >= 11 {
+				n := 138
+				if n > count {
+					n = count
+				}
+				codegen[outIndex] = 18
+				outIndex++
+				codegen[outIndex] = uint8(n - 11)
+				outIndex++
+				w.codegenFreq[18]++
+				count -= n
+			}
+			if count >= 3 {
+				// count >= 3 && count <= 10
+				codegen[outIndex] = 17
+				outIndex++
+				codegen[outIndex] = uint8(count - 3)
+				outIndex++
+				w.codegenFreq[17]++
+				count = 0
+			}
+		}
+		count--
+		for ; count >= 0; count-- {
+			codegen[outIndex] = size
+			outIndex++
+			w.codegenFreq[size]++
+		}
+		// Set up invariant for next time through the loop.
+		size = nextSize
+		count = 1
+	}
+	// Marker indicating the end of the codegen.
+	codegen[outIndex] = badCode
+}
+
+// dynamicSize returns the size of dynamically encoded data in bits.
+func (w *huffmanBitWriter) dynamicSize(litEnc, offEnc *huffmanEncoder, extraBits int) (size, numCodegens int) {
+	numCodegens = len(w.codegenFreq)
+	for numCodegens > 4 && w.codegenFreq[codegenOrder[numCodegens-1]] == 0 {
+		numCodegens--
+	}
+	header := 3 + 5 + 5 + 4 + (3 * numCodegens) +
+		w.codegenEncoding.bitLength(w.codegenFreq[:]) +
+		int(w.codegenFreq[16])*2 +
+		int(w.codegenFreq[17])*3 +
+		int(w.codegenFreq[18])*7
+	size = header +
+		litEnc.bitLength(w.literalFreq) +
+		offEnc.bitLength(w.offsetFreq) +
+		extraBits
+
+	return size, numCodegens
+}
+
+// fixedSize returns the size of dynamically encoded data in bits.
+func (w *huffmanBitWriter) fixedSize(extraBits int) int {
+	return 3 +
+		fixedLiteralEncoding.bitLength(w.literalFreq) +
+		fixedOffsetEncoding.bitLength(w.offsetFreq) +
+		extraBits
+}
+
+// storedSize calculates the stored size, including header.
+// The function returns the size in bits and whether the block
+// fits inside a single block.
+func (w *huffmanBitWriter) storedSize(in []byte) (int, bool) {
+	if in == nil {
+		return 0, false
+	}
+	if len(in) <= maxStoreBlockSize {
+		return (len(in) + 5) * 8, true
+	}
+	return 0, false
+}
+
+func (w *huffmanBitWriter) writeCode(c hcode) {
+	if w.err != nil {
+		return
+	}
+	w.bits |= uint64(c.code) << w.nbits
+	w.nbits += uint(c.len)
+	if w.nbits >= 48 {
+		bits := w.bits
+		w.bits >>= 48
+		w.nbits -= 48
+		n := w.nbytes
+		bytes := w.bytes[n : n+6]
+		bytes[0] = byte(bits)
+		bytes[1] = byte(bits >> 8)
+		bytes[2] = byte(bits >> 16)
+		bytes[3] = byte(bits >> 24)
+		bytes[4] = byte(bits >> 32)
+		bytes[5] = byte(bits >> 40)
+		n += 6
+		if n >= bufferFlushSize {
+			w.write(w.bytes[:n])
+			n = 0
+		}
+		w.nbytes = n
+	}
+}
+
+// Write the header of a dynamic Huffman block to the output stream.
+//
+//	numLiterals  The number of literals specified in codegen
+//	numOffsets   The number of offsets specified in codegen
+//	numCodegens  The number of codegens used in codegen
+func (w *huffmanBitWriter) writeDynamicHeader(numLiterals int, numOffsets int, numCodegens int, isEof bool) {
+	if w.err != nil {
+		return
+	}
+	var firstBits int32 = 4
+	if isEof {
+		firstBits = 5
+	}
+	w.writeBits(firstBits, 3)
+	w.writeBits(int32(numLiterals-257), 5)
+	w.writeBits(int32(numOffsets-1), 5)
+	w.writeBits(int32(numCodegens-4), 4)
+
+	for i := 0; i < numCodegens; i++ {
+		value := uint(w.codegenEncoding.codes[codegenOrder[i]].len)
+		w.writeBits(int32(value), 3)
+	}
+
+	i := 0
+	for {
+		var codeWord int = int(w.codegen[i])
+		i++
+		if codeWord == badCode {
+			break
+		}
+		w.writeCode(w.codegenEncoding.codes[uint32(codeWord)])
+
+		switch codeWord {
+		case 16:
+			w.writeBits(int32(w.codegen[i]), 2)
+			i++
+			break
+		case 17:
+			w.writeBits(int32(w.codegen[i]), 3)
+			i++
+			break
+		case 18:
+			w.writeBits(int32(w.codegen[i]), 7)
+			i++
+			break
+		}
+	}
+}
+
+func (w *huffmanBitWriter) writeStoredHeader(length int, isEof bool) {
+	if w.err != nil {
+		return
+	}
+	var flag int32
+	if isEof {
+		flag = 1
+	}
+	w.writeBits(flag, 3)
+	w.flush()
+	w.writeBits(int32(length), 16)
+	w.writeBits(int32(^uint16(length)), 16)
+}
+
+func (w *huffmanBitWriter) writeFixedHeader(isEof bool) {
+	if w.err != nil {
+		return
+	}
+	// Indicate that we are a fixed Huffman block
+	var value int32 = 2
+	if isEof {
+		value = 3
+	}
+	w.writeBits(value, 3)
+}
+
+// writeBlock will write a block of tokens with the smallest encoding.
+// The original input can be supplied, and if the huffman encoded data
+// is larger than the original bytes, the data will be written as a
+// stored block.
+// If the input is nil, the tokens will always be Huffman encoded.
+func (w *huffmanBitWriter) writeBlock(tokens []token, eof bool, input []byte) {
+	if w.err != nil {
+		return
+	}
+
+	tokens = append(tokens, endBlockMarker)
+	numLiterals, numOffsets := w.indexTokens(tokens)
+
+	var extraBits int
+	storedSize, storable := w.storedSize(input)
+	if storable {
+		// We only bother calculating the costs of the extra bits required by
+		// the length of offset fields (which will be the same for both fixed
+		// and dynamic encoding), if we need to compare those two encodings
+		// against stored encoding.
+		for lengthCode := lengthCodesStart + 8; lengthCode < numLiterals; lengthCode++ {
+			// First eight length codes have extra size = 0.
+			extraBits += int(w.literalFreq[lengthCode]) * int(lengthExtraBits[lengthCode-lengthCodesStart])
+		}
+		for offsetCode := 4; offsetCode < numOffsets; offsetCode++ {
+			// First four offset codes have extra size = 0.
+			extraBits += int(w.offsetFreq[offsetCode]) * int(offsetExtraBits[offsetCode])
+		}
+	}
+
+	// Figure out smallest code.
+	// Fixed Huffman baseline.
+	var literalEncoding = fixedLiteralEncoding
+	var offsetEncoding = fixedOffsetEncoding
+	var size = w.fixedSize(extraBits)
+
+	// Dynamic Huffman?
+	var numCodegens int
+
+	// Generate codegen and codegenFrequencies, which indicates how to encode
+	// the literalEncoding and the offsetEncoding.
+	w.generateCodegen(numLiterals, numOffsets, w.literalEncoding, w.offsetEncoding)
+	w.codegenEncoding.generate(w.codegenFreq[:], 7)
+	dynamicSize, numCodegens := w.dynamicSize(w.literalEncoding, w.offsetEncoding, extraBits)
+
+	if dynamicSize < size {
+		size = dynamicSize
+		literalEncoding = w.literalEncoding
+		offsetEncoding = w.offsetEncoding
+	}
+
+	// Stored bytes?
+	if storable && storedSize < size {
+		w.writeStoredHeader(len(input), eof)
+		w.writeBytes(input)
+		return
+	}
+
+	// Huffman.
+	if literalEncoding == fixedLiteralEncoding {
+		w.writeFixedHeader(eof)
+	} else {
+		w.writeDynamicHeader(numLiterals, numOffsets, numCodegens, eof)
+	}
+
+	// Write the tokens.
+	w.writeTokens(tokens, literalEncoding.codes, offsetEncoding.codes)
+}
+
+// writeBlockDynamic encodes a block using a dynamic Huffman table.
+// This should be used if the symbols used have a disproportionate
+// histogram distribution.
+// If input is supplied and the compression savings are below 1/16th of the
+// input size the block is stored.
+func (w *huffmanBitWriter) writeBlockDynamic(tokens []token, eof bool, input []byte) {
+	if w.err != nil {
+		return
+	}
+
+	tokens = append(tokens, endBlockMarker)
+	numLiterals, numOffsets := w.indexTokens(tokens)
+
+	// Generate codegen and codegenFrequencies, which indicates how to encode
+	// the literalEncoding and the offsetEncoding.
+	w.generateCodegen(numLiterals, numOffsets, w.literalEncoding, w.offsetEncoding)
+	w.codegenEncoding.generate(w.codegenFreq[:], 7)
+	size, numCodegens := w.dynamicSize(w.literalEncoding, w.offsetEncoding, 0)
+
+	// Store bytes, if we don't get a reasonable improvement.
+	if ssize, storable := w.storedSize(input); storable && ssize < (size+size>>4) {
+		w.writeStoredHeader(len(input), eof)
+		w.writeBytes(input)
+		return
+	}
+
+	// Write Huffman table.
+	w.writeDynamicHeader(numLiterals, numOffsets, numCodegens, eof)
+
+	// Write the tokens.
+	w.writeTokens(tokens, w.literalEncoding.codes, w.offsetEncoding.codes)
+}
+
+// indexTokens indexes a slice of tokens, and updates
+// literalFreq and offsetFreq, and generates literalEncoding
+// and offsetEncoding.
+// The number of literal and offset tokens is returned.
+func (w *huffmanBitWriter) indexTokens(tokens []token) (numLiterals, numOffsets int) {
+	for i := range w.literalFreq {
+		w.literalFreq[i] = 0
+	}
+	for i := range w.offsetFreq {
+		w.offsetFreq[i] = 0
+	}
+
+	for _, t := range tokens {
+		if t < matchType {
+			w.literalFreq[t.literal()]++
+			continue
+		}
+		length := t.length()
+		offset := t.offset()
+		w.literalFreq[lengthCodesStart+lengthCode(length)]++
+		w.offsetFreq[offsetCode(offset)]++
+	}
+
+	// get the number of literals
+	numLiterals = len(w.literalFreq)
+	for w.literalFreq[numLiterals-1] == 0 {
+		numLiterals--
+	}
+	// get the number of offsets
+	numOffsets = len(w.offsetFreq)
+	for numOffsets > 0 && w.offsetFreq[numOffsets-1] == 0 {
+		numOffsets--
+	}
+	if numOffsets == 0 {
+		// We haven't found a single match. If we want to go with the dynamic encoding,
+		// we should count at least one offset to be sure that the offset huffman tree could be encoded.
+		w.offsetFreq[0] = 1
+		numOffsets = 1
+	}
+	w.literalEncoding.generate(w.literalFreq, 15)
+	w.offsetEncoding.generate(w.offsetFreq, 15)
+	return
+}
+
+// writeTokens writes a slice of tokens to the output.
+// codes for literal and offset encoding must be supplied.
+func (w *huffmanBitWriter) writeTokens(tokens []token, leCodes, oeCodes []hcode) {
+	if w.err != nil {
+		return
+	}
+	for _, t := range tokens {
+		if t < matchType {
+			w.writeCode(leCodes[t.literal()])
+			continue
+		}
+		// Write the length
+		length := t.length()
+		lengthCode := lengthCode(length)
+		w.writeCode(leCodes[lengthCode+lengthCodesStart])
+		extraLengthBits := uint(lengthExtraBits[lengthCode])
+		if extraLengthBits > 0 {
+			extraLength := int32(length - lengthBase[lengthCode])
+			w.writeBits(extraLength, extraLengthBits)
+		}
+		// Write the offset
+		offset := t.offset()
+		offsetCode := offsetCode(offset)
+		w.writeCode(oeCodes[offsetCode])
+		extraOffsetBits := uint(offsetExtraBits[offsetCode])
+		if extraOffsetBits > 0 {
+			extraOffset := int32(offset - offsetBase[offsetCode])
+			w.writeBits(extraOffset, extraOffsetBits)
+		}
+	}
+}
+
+// huffOffset is a static offset encoder used for huffman only encoding.
+// It can be reused since we will not be encoding offset values.
+var huffOffset *huffmanEncoder
+
+func init() {
+	offsetFreq := make([]int32, offsetCodeCount)
+	offsetFreq[0] = 1
+	huffOffset = newHuffmanEncoder(offsetCodeCount)
+	huffOffset.generate(offsetFreq, 15)
+}
+
+// writeBlockHuff encodes a block of bytes as either
+// Huffman encoded literals or uncompressed bytes if the
+// results only gains very little from compression.
+func (w *huffmanBitWriter) writeBlockHuff(eof bool, input []byte) {
+	if w.err != nil {
+		return
+	}
+
+	// Clear histogram
+	for i := range w.literalFreq {
+		w.literalFreq[i] = 0
+	}
+
+	// Add everything as literals
+	histogram(input, w.literalFreq)
+
+	w.literalFreq[endBlockMarker] = 1
+
+	const numLiterals = endBlockMarker + 1
+	w.offsetFreq[0] = 1
+	const numOffsets = 1
+
+	w.literalEncoding.generate(w.literalFreq, 15)
+
+	// Figure out smallest code.
+	// Always use dynamic Huffman or Store
+	var numCodegens int
+
+	// Generate codegen and codegenFrequencies, which indicates how to encode
+	// the literalEncoding and the offsetEncoding.
+	w.generateCodegen(numLiterals, numOffsets, w.literalEncoding, huffOffset)
+	w.codegenEncoding.generate(w.codegenFreq[:], 7)
+	size, numCodegens := w.dynamicSize(w.literalEncoding, huffOffset, 0)
+
+	// Store bytes, if we don't get a reasonable improvement.
+	if ssize, storable := w.storedSize(input); storable && ssize < (size+size>>4) {
+		w.writeStoredHeader(len(input), eof)
+		w.writeBytes(input)
+		return
+	}
+
+	// Huffman.
+	w.writeDynamicHeader(numLiterals, numOffsets, numCodegens, eof)
+	encoding := w.literalEncoding.codes[:257]
+	n := w.nbytes
+	for _, t := range input {
+		// Bitwriting inlined, ~30% speedup
+		c := encoding[t]
+		w.bits |= uint64(c.code) << w.nbits
+		w.nbits += uint(c.len)
+		if w.nbits < 48 {
+			continue
+		}
+		// Store 6 bytes
+		bits := w.bits
+		w.bits >>= 48
+		w.nbits -= 48
+		bytes := w.bytes[n : n+6]
+		bytes[0] = byte(bits)
+		bytes[1] = byte(bits >> 8)
+		bytes[2] = byte(bits >> 16)
+		bytes[3] = byte(bits >> 24)
+		bytes[4] = byte(bits >> 32)
+		bytes[5] = byte(bits >> 40)
+		n += 6
+		if n < bufferFlushSize {
+			continue
+		}
+		w.write(w.bytes[:n])
+		if w.err != nil {
+			return // Return early in the event of write failures
+		}
+		n = 0
+	}
+	w.nbytes = n
+	w.writeCode(encoding[endBlockMarker])
+}
+
+// histogram accumulates a histogram of b in h.
+//
+// len(h) must be >= 256, and h's elements must be all zeroes.
+func histogram(b []byte, h []int32) {
+	h = h[:256]
+	for _, t := range b {
+		h[t]++
+	}
+}
diff --git a/contrib/go/_std_1.19/src/compress/flate/huffman_code.go b/contrib/go/_std_1.19/src/compress/flate/huffman_code.go
new file mode 100644
index 0000000000..a3fe80b442
--- /dev/null
+++ b/contrib/go/_std_1.19/src/compress/flate/huffman_code.go
@@ -0,0 +1,348 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package flate
+
+import (
+	"math"
+	"math/bits"
+	"sort"
+)
+
+// hcode is a huffman code with a bit code and bit length.
+type hcode struct {
+	code, len uint16
+}
+
+type huffmanEncoder struct {
+	codes     []hcode
+	freqcache []literalNode
+	bitCount  [17]int32
+	lns       byLiteral // stored to avoid repeated allocation in generate
+	lfs       byFreq    // stored to avoid repeated allocation in generate
+}
+
+type literalNode struct {
+	literal uint16
+	freq    int32
+}
+
+// A levelInfo describes the state of the constructed tree for a given depth.
+type levelInfo struct {
+	// Our level.  for better printing
+	level int32
+
+	// The frequency of the last node at this level
+	lastFreq int32
+
+	// The frequency of the next character to add to this level
+	nextCharFreq int32
+
+	// The frequency of the next pair (from level below) to add to this level.
+	// Only valid if the "needed" value of the next lower level is 0.
+	nextPairFreq int32
+
+	// The number of chains remaining to generate for this level before moving
+	// up to the next level
+	needed int32
+}
+
+// set sets the code and length of an hcode.
+func (h *hcode) set(code uint16, length uint16) {
+	h.len = length
+	h.code = code
+}
+
+func maxNode() literalNode { return literalNode{math.MaxUint16, math.MaxInt32} }
+
+func newHuffmanEncoder(size int) *huffmanEncoder {
+	return &huffmanEncoder{codes: make([]hcode, size)}
+}
+
+// Generates a HuffmanCode corresponding to the fixed literal table
+func generateFixedLiteralEncoding() *huffmanEncoder {
+	h := newHuffmanEncoder(maxNumLit)
+	codes := h.codes
+	var ch uint16
+	for ch = 0; ch < maxNumLit; ch++ {
+		var bits uint16
+		var size uint16
+		switch {
+		case ch < 144:
+			// size 8, 000110000  .. 10111111
+			bits = ch + 48
+			size = 8
+			break
+		case ch < 256:
+			// size 9, 110010000 .. 111111111
+			bits = ch + 400 - 144
+			size = 9
+			break
+		case ch < 280:
+			// size 7, 0000000 .. 0010111
+			bits = ch - 256
+			size = 7
+			break
+		default:
+			// size 8, 11000000 .. 11000111
+			bits = ch + 192 - 280
+			size = 8
+		}
+		codes[ch] = hcode{code: reverseBits(bits, byte(size)), len: size}
+	}
+	return h
+}
+
+func generateFixedOffsetEncoding() *huffmanEncoder {
+	h := newHuffmanEncoder(30)
+	codes := h.codes
+	for ch := range codes {
+		codes[ch] = hcode{code: reverseBits(uint16(ch), 5), len: 5}
+	}
+	return h
+}
+
+var fixedLiteralEncoding *huffmanEncoder = generateFixedLiteralEncoding()
+var fixedOffsetEncoding *huffmanEncoder = generateFixedOffsetEncoding()
+
+func (h *huffmanEncoder) bitLength(freq []int32) int {
+	var total int
+	for i, f := range freq {
+		if f != 0 {
+			total += int(f) * int(h.codes[i].len)
+		}
+	}
+	return total
+}
+
+const maxBitsLimit = 16
+
+// bitCounts computes the number of literals assigned to each bit size in the Huffman encoding.
+// It is only called when list.length >= 3.
+// The cases of 0, 1, and 2 literals are handled by special case code.
+//
+// list is an array of the literals with non-zero frequencies
+// and their associated frequencies. The array is in order of increasing
+// frequency and has as its last element a special element with frequency
+// MaxInt32.
+//
+// maxBits is the maximum number of bits that should be used to encode any literal.
+// It must be less than 16.
+//
+// bitCounts returns an integer slice in which slice[i] indicates the number of literals
+// that should be encoded in i bits.
+func (h *huffmanEncoder) bitCounts(list []literalNode, maxBits int32) []int32 {
+	if maxBits >= maxBitsLimit {
+		panic("flate: maxBits too large")
+	}
+	n := int32(len(list))
+	list = list[0 : n+1]
+	list[n] = maxNode()
+
+	// The tree can't have greater depth than n - 1, no matter what. This
+	// saves a little bit of work in some small cases
+	if maxBits > n-1 {
+		maxBits = n - 1
+	}
+
+	// Create information about each of the levels.
+	// A bogus "Level 0" whose sole purpose is so that
+	// level1.prev.needed==0.  This makes level1.nextPairFreq
+	// be a legitimate value that never gets chosen.
+	var levels [maxBitsLimit]levelInfo
+	// leafCounts[i] counts the number of literals at the left
+	// of ancestors of the rightmost node at level i.
+	// leafCounts[i][j] is the number of literals at the left
+	// of the level j ancestor.
+	var leafCounts [maxBitsLimit][maxBitsLimit]int32
+
+	for level := int32(1); level <= maxBits; level++ {
+		// For every level, the first two items are the first two characters.
+		// We initialize the levels as if we had already figured this out.
+		levels[level] = levelInfo{
+			level:        level,
+			lastFreq:     list[1].freq,
+			nextCharFreq: list[2].freq,
+			nextPairFreq: list[0].freq + list[1].freq,
+		}
+		leafCounts[level][level] = 2
+		if level == 1 {
+			levels[level].nextPairFreq = math.MaxInt32
+		}
+	}
+
+	// We need a total of 2*n - 2 items at top level and have already generated 2.
+	levels[maxBits].needed = 2*n - 4
+
+	level := maxBits
+	for {
+		l := &levels[level]
+		if l.nextPairFreq == math.MaxInt32 && l.nextCharFreq == math.MaxInt32 {
+			// We've run out of both leafs and pairs.
+			// End all calculations for this level.
+			// To make sure we never come back to this level or any lower level,
+			// set nextPairFreq impossibly large.
+			l.needed = 0
+			levels[level+1].nextPairFreq = math.MaxInt32
+			level++
+			continue
+		}
+
+		prevFreq := l.lastFreq
+		if l.nextCharFreq < l.nextPairFreq {
+			// The next item on this row is a leaf node.
+			n := leafCounts[level][level] + 1
+			l.lastFreq = l.nextCharFreq
+			// Lower leafCounts are the same of the previous node.
+			leafCounts[level][level] = n
+			l.nextCharFreq = list[n].freq
+		} else {
+			// The next item on this row is a pair from the previous row.
+			// nextPairFreq isn't valid until we generate two
+			// more values in the level below
+			l.lastFreq = l.nextPairFreq
+			// Take leaf counts from the lower level, except counts[level] remains the same.
+			copy(leafCounts[level][:level], leafCounts[level-1][:level])
+			levels[l.level-1].needed = 2
+		}
+
+		if l.needed--; l.needed == 0 {
+			// We've done everything we need to do for this level.
+			// Continue calculating one level up. Fill in nextPairFreq
+			// of that level with the sum of the two nodes we've just calculated on
+			// this level.
+			if l.level == maxBits {
+				// All done!
+				break
+			}
+			levels[l.level+1].nextPairFreq = prevFreq + l.lastFreq
+			level++
+		} else {
+			// If we stole from below, move down temporarily to replenish it.
+			for levels[level-1].needed > 0 {
+				level--
+			}
+		}
+	}
+
+	// Somethings is wrong if at the end, the top level is null or hasn't used
+	// all of the leaves.
+	if leafCounts[maxBits][maxBits] != n {
+		panic("leafCounts[maxBits][maxBits] != n")
+	}
+
+	bitCount := h.bitCount[:maxBits+1]
+	bits := 1
+	counts := &leafCounts[maxBits]
+	for level := maxBits; level > 0; level-- {
+		// chain.leafCount gives the number of literals requiring at least "bits"
+		// bits to encode.
+		bitCount[bits] = counts[level] - counts[level-1]
+		bits++
+	}
+	return bitCount
+}
+
+// Look at the leaves and assign them a bit count and an encoding as specified
+// in RFC 1951 3.2.2
+func (h *huffmanEncoder) assignEncodingAndSize(bitCount []int32, list []literalNode) {
+	code := uint16(0)
+	for n, bits := range bitCount {
+		code <<= 1
+		if n == 0 || bits == 0 {
+			continue
+		}
+		// The literals list[len(list)-bits] .. list[len(list)-bits]
+		// are encoded using "bits" bits, and get the values
+		// code, code + 1, ....  The code values are
+		// assigned in literal order (not frequency order).
+		chunk := list[len(list)-int(bits):]
+
+		h.lns.sort(chunk)
+		for _, node := range chunk {
+			h.codes[node.literal] = hcode{code: reverseBits(code, uint8(n)), len: uint16(n)}
+			code++
+		}
+		list = list[0 : len(list)-int(bits)]
+	}
+}
+
+// Update this Huffman Code object to be the minimum code for the specified frequency count.
+//
+// freq is an array of frequencies, in which freq[i] gives the frequency of literal i.
+// maxBits  The maximum number of bits to use for any literal.
+func (h *huffmanEncoder) generate(freq []int32, maxBits int32) {
+	if h.freqcache == nil {
+		// Allocate a reusable buffer with the longest possible frequency table.
+		// Possible lengths are codegenCodeCount, offsetCodeCount and maxNumLit.
+		// The largest of these is maxNumLit, so we allocate for that case.
+		h.freqcache = make([]literalNode, maxNumLit+1)
+	}
+	list := h.freqcache[:len(freq)+1]
+	// Number of non-zero literals
+	count := 0
+	// Set list to be the set of all non-zero literals and their frequencies
+	for i, f := range freq {
+		if f != 0 {
+			list[count] = literalNode{uint16(i), f}
+			count++
+		} else {
+			h.codes[i].len = 0
+		}
+	}
+
+	list = list[:count]
+	if count <= 2 {
+		// Handle the small cases here, because they are awkward for the general case code. With
+		// two or fewer literals, everything has bit length 1.
+		for i, node := range list {
+			// "list" is in order of increasing literal value.
+			h.codes[node.literal].set(uint16(i), 1)
+		}
+		return
+	}
+	h.lfs.sort(list)
+
+	// Get the number of literals for each bit count
+	bitCount := h.bitCounts(list, maxBits)
+	// And do the assignment
+	h.assignEncodingAndSize(bitCount, list)
+}
+
+type byLiteral []literalNode
+
+func (s *byLiteral) sort(a []literalNode) {
+	*s = byLiteral(a)
+	sort.Sort(s)
+}
+
+func (s byLiteral) Len() int { return len(s) }
+
+func (s byLiteral) Less(i, j int) bool {
+	return s[i].literal < s[j].literal
+}
+
+func (s byLiteral) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
+
+type byFreq []literalNode
+
+func (s *byFreq) sort(a []literalNode) {
+	*s = byFreq(a)
+	sort.Sort(s)
+}
+
+func (s byFreq) Len() int { return len(s) }
+
+func (s byFreq) Less(i, j int) bool {
+	if s[i].freq == s[j].freq {
+		return s[i].literal < s[j].literal
+	}
+	return s[i].freq < s[j].freq
+}
+
+func (s byFreq) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
+
+func reverseBits(number uint16, bitLength byte) uint16 {
+	return bits.Reverse16(number << (16 - bitLength))
+}
diff --git a/contrib/go/_std_1.18/src/compress/flate/inflate.go b/contrib/go/_std_1.19/src/compress/flate/inflate.go
index 49921398e2..49921398e2 100644
--- a/contrib/go/_std_1.18/src/compress/flate/inflate.go
+++ b/contrib/go/_std_1.19/src/compress/flate/inflate.go
diff --git a/contrib/go/_std_1.18/src/compress/flate/token.go b/contrib/go/_std_1.19/src/compress/flate/token.go
index ae01391f9c..ae01391f9c 100644
--- a/contrib/go/_std_1.18/src/compress/flate/token.go
+++ b/contrib/go/_std_1.19/src/compress/flate/token.go
diff --git a/contrib/go/_std_1.19/src/compress/gzip/gunzip.go b/contrib/go/_std_1.19/src/compress/gzip/gunzip.go
new file mode 100644
index 0000000000..ba8de97e6a
--- /dev/null
+++ b/contrib/go/_std_1.19/src/compress/gzip/gunzip.go
@@ -0,0 +1,290 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package gzip implements reading and writing of gzip format compressed files,
+// as specified in RFC 1952.
+package gzip
+
+import (
+	"bufio"
+	"compress/flate"
+	"encoding/binary"
+	"errors"
+	"hash/crc32"
+	"io"
+	"time"
+)
+
+const (
+	gzipID1     = 0x1f
+	gzipID2     = 0x8b
+	gzipDeflate = 8
+	flagText    = 1 << 0
+	flagHdrCrc  = 1 << 1
+	flagExtra   = 1 << 2
+	flagName    = 1 << 3
+	flagComment = 1 << 4
+)
+
+var (
+	// ErrChecksum is returned when reading GZIP data that has an invalid checksum.
+	ErrChecksum = errors.New("gzip: invalid checksum")
+	// ErrHeader is returned when reading GZIP data that has an invalid header.
+	ErrHeader = errors.New("gzip: invalid header")
+)
+
+var le = binary.LittleEndian
+
+// noEOF converts io.EOF to io.ErrUnexpectedEOF.
+func noEOF(err error) error {
+	if err == io.EOF {
+		return io.ErrUnexpectedEOF
+	}
+	return err
+}
+
+// The gzip file stores a header giving metadata about the compressed file.
+// That header is exposed as the fields of the Writer and Reader structs.
+//
+// Strings must be UTF-8 encoded and may only contain Unicode code points
+// U+0001 through U+00FF, due to limitations of the GZIP file format.
+type Header struct {
+	Comment string    // comment
+	Extra   []byte    // "extra data"
+	ModTime time.Time // modification time
+	Name    string    // file name
+	OS      byte      // operating system type
+}
+
+// A Reader is an io.Reader that can be read to retrieve
+// uncompressed data from a gzip-format compressed file.
+//
+// In general, a gzip file can be a concatenation of gzip files,
+// each with its own header. Reads from the Reader
+// return the concatenation of the uncompressed data of each.
+// Only the first header is recorded in the Reader fields.
+//
+// Gzip files store a length and checksum of the uncompressed data.
+// The Reader will return an ErrChecksum when Read
+// reaches the end of the uncompressed data if it does not
+// have the expected length or checksum. Clients should treat data
+// returned by Read as tentative until they receive the io.EOF
+// marking the end of the data.
+type Reader struct {
+	Header       // valid after NewReader or Reader.Reset
+	r            flate.Reader
+	decompressor io.ReadCloser
+	digest       uint32 // CRC-32, IEEE polynomial (section 8)
+	size         uint32 // Uncompressed size (section 2.3.1)
+	buf          [512]byte
+	err          error
+	multistream  bool
+}
+
+// NewReader creates a new Reader reading the given reader.
+// If r does not also implement io.ByteReader,
+// the decompressor may read more data than necessary from r.
+//
+// It is the caller's responsibility to call Close on the Reader when done.
+//
+// The Reader.Header fields will be valid in the Reader returned.
+func NewReader(r io.Reader) (*Reader, error) {
+	z := new(Reader)
+	if err := z.Reset(r); err != nil {
+		return nil, err
+	}
+	return z, nil
+}
+
+// Reset discards the Reader z's state and makes it equivalent to the
+// result of its original state from NewReader, but reading from r instead.
+// This permits reusing a Reader rather than allocating a new one.
+func (z *Reader) Reset(r io.Reader) error {
+	*z = Reader{
+		decompressor: z.decompressor,
+		multistream:  true,
+	}
+	if rr, ok := r.(flate.Reader); ok {
+		z.r = rr
+	} else {
+		z.r = bufio.NewReader(r)
+	}
+	z.Header, z.err = z.readHeader()
+	return z.err
+}
+
+// Multistream controls whether the reader supports multistream files.
+//
+// If enabled (the default), the Reader expects the input to be a sequence
+// of individually gzipped data streams, each with its own header and
+// trailer, ending at EOF. The effect is that the concatenation of a sequence
+// of gzipped files is treated as equivalent to the gzip of the concatenation
+// of the sequence. This is standard behavior for gzip readers.
+//
+// Calling Multistream(false) disables this behavior; disabling the behavior
+// can be useful when reading file formats that distinguish individual gzip
+// data streams or mix gzip data streams with other data streams.
+// In this mode, when the Reader reaches the end of the data stream,
+// Read returns io.EOF. The underlying reader must implement io.ByteReader
+// in order to be left positioned just after the gzip stream.
+// To start the next stream, call z.Reset(r) followed by z.Multistream(false).
+// If there is no next stream, z.Reset(r) will return io.EOF.
+func (z *Reader) Multistream(ok bool) {
+	z.multistream = ok
+}
+
+// readString reads a NUL-terminated string from z.r.
+// It treats the bytes read as being encoded as ISO 8859-1 (Latin-1) and
+// will output a string encoded using UTF-8.
+// This method always updates z.digest with the data read.
+func (z *Reader) readString() (string, error) {
+	var err error
+	needConv := false
+	for i := 0; ; i++ {
+		if i >= len(z.buf) {
+			return "", ErrHeader
+		}
+		z.buf[i], err = z.r.ReadByte()
+		if err != nil {
+			return "", err
+		}
+		if z.buf[i] > 0x7f {
+			needConv = true
+		}
+		if z.buf[i] == 0 {
+			// Digest covers the NUL terminator.
+			z.digest = crc32.Update(z.digest, crc32.IEEETable, z.buf[:i+1])
+
+			// Strings are ISO 8859-1, Latin-1 (RFC 1952, section 2.3.1).
+			if needConv {
+				s := make([]rune, 0, i)
+				for _, v := range z.buf[:i] {
+					s = append(s, rune(v))
+				}
+				return string(s), nil
+			}
+			return string(z.buf[:i]), nil
+		}
+	}
+}
+
+// readHeader reads the GZIP header according to section 2.3.1.
+// This method does not set z.err.
+func (z *Reader) readHeader() (hdr Header, err error) {
+	if _, err = io.ReadFull(z.r, z.buf[:10]); err != nil {
+		// RFC 1952, section 2.2, says the following:
+		//	A gzip file consists of a series of "members" (compressed data sets).
+		//
+		// Other than this, the specification does not clarify whether a
+		// "series" is defined as "one or more" or "zero or more". To err on the
+		// side of caution, Go interprets this to mean "zero or more".
+		// Thus, it is okay to return io.EOF here.
+		return hdr, err
+	}
+	if z.buf[0] != gzipID1 || z.buf[1] != gzipID2 || z.buf[2] != gzipDeflate {
+		return hdr, ErrHeader
+	}
+	flg := z.buf[3]
+	if t := int64(le.Uint32(z.buf[4:8])); t > 0 {
+		// Section 2.3.1, the zero value for MTIME means that the
+		// modified time is not set.
+		hdr.ModTime = time.Unix(t, 0)
+	}
+	// z.buf[8] is XFL and is currently ignored.
+	hdr.OS = z.buf[9]
+	z.digest = crc32.ChecksumIEEE(z.buf[:10])
+
+	if flg&flagExtra != 0 {
+		if _, err = io.ReadFull(z.r, z.buf[:2]); err != nil {
+			return hdr, noEOF(err)
+		}
+		z.digest = crc32.Update(z.digest, crc32.IEEETable, z.buf[:2])
+		data := make([]byte, le.Uint16(z.buf[:2]))
+		if _, err = io.ReadFull(z.r, data); err != nil {
+			return hdr, noEOF(err)
+		}
+		z.digest = crc32.Update(z.digest, crc32.IEEETable, data)
+		hdr.Extra = data
+	}
+
+	var s string
+	if flg&flagName != 0 {
+		if s, err = z.readString(); err != nil {
+			return hdr, noEOF(err)
+		}
+		hdr.Name = s
+	}
+
+	if flg&flagComment != 0 {
+		if s, err = z.readString(); err != nil {
+			return hdr, noEOF(err)
+		}
+		hdr.Comment = s
+	}
+
+	if flg&flagHdrCrc != 0 {
+		if _, err = io.ReadFull(z.r, z.buf[:2]); err != nil {
+			return hdr, noEOF(err)
+		}
+		digest := le.Uint16(z.buf[:2])
+		if digest != uint16(z.digest) {
+			return hdr, ErrHeader
+		}
+	}
+
+	z.digest = 0
+	if z.decompressor == nil {
+		z.decompressor = flate.NewReader(z.r)
+	} else {
+		z.decompressor.(flate.Resetter).Reset(z.r, nil)
+	}
+	return hdr, nil
+}
+
+// Read implements io.Reader, reading uncompressed bytes from its underlying Reader.
+func (z *Reader) Read(p []byte) (n int, err error) {
+	if z.err != nil {
+		return 0, z.err
+	}
+
+	for n == 0 {
+		n, z.err = z.decompressor.Read(p)
+		z.digest = crc32.Update(z.digest, crc32.IEEETable, p[:n])
+		z.size += uint32(n)
+		if z.err != io.EOF {
+			// In the normal case we return here.
+			return n, z.err
+		}
+
+		// Finished file; check checksum and size.
+		if _, err := io.ReadFull(z.r, z.buf[:8]); err != nil {
+			z.err = noEOF(err)
+			return n, z.err
+		}
+		digest := le.Uint32(z.buf[:4])
+		size := le.Uint32(z.buf[4:8])
+		if digest != z.digest || size != z.size {
+			z.err = ErrChecksum
+			return n, z.err
+		}
+		z.digest, z.size = 0, 0
+
+		// File is ok; check if there is another.
+		if !z.multistream {
+			return n, io.EOF
+		}
+		z.err = nil // Remove io.EOF
+
+		if _, z.err = z.readHeader(); z.err != nil {
+			return n, z.err
+		}
+	}
+
+	return n, nil
+}
+
+// Close closes the Reader. It does not close the underlying io.Reader.
+// In order for the GZIP checksum to be verified, the reader must be
+// fully consumed until the io.EOF.
+func (z *Reader) Close() error { return z.decompressor.Close() }
diff --git a/contrib/go/_std_1.18/src/compress/gzip/gzip.go b/contrib/go/_std_1.19/src/compress/gzip/gzip.go
index eaeb185795..eaeb185795 100644
--- a/contrib/go/_std_1.18/src/compress/gzip/gzip.go
+++ b/contrib/go/_std_1.19/src/compress/gzip/gzip.go
diff --git a/contrib/go/_std_1.19/src/container/list/list.go b/contrib/go/_std_1.19/src/container/list/list.go
new file mode 100644
index 0000000000..f2d77f0560
--- /dev/null
+++ b/contrib/go/_std_1.19/src/container/list/list.go
@@ -0,0 +1,235 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package list implements a doubly linked list.
+//
+// To iterate over a list (where l is a *List):
+//
+//	for e := l.Front(); e != nil; e = e.Next() {
+//		// do something with e.Value
+//	}
+package list
+
+// Element is an element of a linked list.
+type Element struct {
+	// Next and previous pointers in the doubly-linked list of elements.
+	// To simplify the implementation, internally a list l is implemented
+	// as a ring, such that &l.root is both the next element of the last
+	// list element (l.Back()) and the previous element of the first list
+	// element (l.Front()).
+	next, prev *Element
+
+	// The list to which this element belongs.
+	list *List
+
+	// The value stored with this element.
+	Value any
+}
+
+// Next returns the next list element or nil.
+func (e *Element) Next() *Element {
+	if p := e.next; e.list != nil && p != &e.list.root {
+		return p
+	}
+	return nil
+}
+
+// Prev returns the previous list element or nil.
+func (e *Element) Prev() *Element {
+	if p := e.prev; e.list != nil && p != &e.list.root {
+		return p
+	}
+	return nil
+}
+
+// List represents a doubly linked list.
+// The zero value for List is an empty list ready to use.
+type List struct {
+	root Element // sentinel list element, only &root, root.prev, and root.next are used
+	len  int     // current list length excluding (this) sentinel element
+}
+
+// Init initializes or clears list l.
+func (l *List) Init() *List {
+	l.root.next = &l.root
+	l.root.prev = &l.root
+	l.len = 0
+	return l
+}
+
+// New returns an initialized list.
+func New() *List { return new(List).Init() }
+
+// Len returns the number of elements of list l.
+// The complexity is O(1).
+func (l *List) Len() int { return l.len }
+
+// Front returns the first element of list l or nil if the list is empty.
+func (l *List) Front() *Element {
+	if l.len == 0 {
+		return nil
+	}
+	return l.root.next
+}
+
+// Back returns the last element of list l or nil if the list is empty.
+func (l *List) Back() *Element {
+	if l.len == 0 {
+		return nil
+	}
+	return l.root.prev
+}
+
+// lazyInit lazily initializes a zero List value.
+func (l *List) lazyInit() {
+	if l.root.next == nil {
+		l.Init()
+	}
+}
+
+// insert inserts e after at, increments l.len, and returns e.
+func (l *List) insert(e, at *Element) *Element {
+	e.prev = at
+	e.next = at.next
+	e.prev.next = e
+	e.next.prev = e
+	e.list = l
+	l.len++
+	return e
+}
+
+// insertValue is a convenience wrapper for insert(&Element{Value: v}, at).
+func (l *List) insertValue(v any, at *Element) *Element {
+	return l.insert(&Element{Value: v}, at)
+}
+
+// remove removes e from its list, decrements l.len
+func (l *List) remove(e *Element) {
+	e.prev.next = e.next
+	e.next.prev = e.prev
+	e.next = nil // avoid memory leaks
+	e.prev = nil // avoid memory leaks
+	e.list = nil
+	l.len--
+}
+
+// move moves e to next to at.
+func (l *List) move(e, at *Element) {
+	if e == at {
+		return
+	}
+	e.prev.next = e.next
+	e.next.prev = e.prev
+
+	e.prev = at
+	e.next = at.next
+	e.prev.next = e
+	e.next.prev = e
+}
+
+// Remove removes e from l if e is an element of list l.
+// It returns the element value e.Value.
+// The element must not be nil.
+func (l *List) Remove(e *Element) any {
+	if e.list == l {
+		// if e.list == l, l must have been initialized when e was inserted
+		// in l or l == nil (e is a zero Element) and l.remove will crash
+		l.remove(e)
+	}
+	return e.Value
+}
+
+// PushFront inserts a new element e with value v at the front of list l and returns e.
+func (l *List) PushFront(v any) *Element {
+	l.lazyInit()
+	return l.insertValue(v, &l.root)
+}
+
+// PushBack inserts a new element e with value v at the back of list l and returns e.
+func (l *List) PushBack(v any) *Element {
+	l.lazyInit()
+	return l.insertValue(v, l.root.prev)
+}
+
+// InsertBefore inserts a new element e with value v immediately before mark and returns e.
+// If mark is not an element of l, the list is not modified.
+// The mark must not be nil.
+func (l *List) InsertBefore(v any, mark *Element) *Element {
+	if mark.list != l {
+		return nil
+	}
+	// see comment in List.Remove about initialization of l
+	return l.insertValue(v, mark.prev)
+}
+
+// InsertAfter inserts a new element e with value v immediately after mark and returns e.
+// If mark is not an element of l, the list is not modified.
+// The mark must not be nil.
+func (l *List) InsertAfter(v any, mark *Element) *Element {
+	if mark.list != l {
+		return nil
+	}
+	// see comment in List.Remove about initialization of l
+	return l.insertValue(v, mark)
+}
+
+// MoveToFront moves element e to the front of list l.
+// If e is not an element of l, the list is not modified.
+// The element must not be nil.
+func (l *List) MoveToFront(e *Element) {
+	if e.list != l || l.root.next == e {
+		return
+	}
+	// see comment in List.Remove about initialization of l
+	l.move(e, &l.root)
+}
+
+// MoveToBack moves element e to the back of list l.
+// If e is not an element of l, the list is not modified.
+// The element must not be nil.
+func (l *List) MoveToBack(e *Element) {
+	if e.list != l || l.root.prev == e {
+		return
+	}
+	// see comment in List.Remove about initialization of l
+	l.move(e, l.root.prev)
+}
+
+// MoveBefore moves element e to its new position before mark.
+// If e or mark is not an element of l, or e == mark, the list is not modified.
+// The element and mark must not be nil.
+func (l *List) MoveBefore(e, mark *Element) {
+	if e.list != l || e == mark || mark.list != l {
+		return
+	}
+	l.move(e, mark.prev)
+}
+
+// MoveAfter moves element e to its new position after mark.
+// If e or mark is not an element of l, or e == mark, the list is not modified.
+// The element and mark must not be nil.
+func (l *List) MoveAfter(e, mark *Element) {
+	if e.list != l || e == mark || mark.list != l {
+		return
+	}
+	l.move(e, mark)
+}
+
+// PushBackList inserts a copy of another list at the back of list l.
+// The lists l and other may be the same. They must not be nil.
+func (l *List) PushBackList(other *List) {
+	l.lazyInit()
+	for i, e := other.Len(), other.Front(); i > 0; i, e = i-1, e.Next() {
+		l.insertValue(e.Value, l.root.prev)
+	}
+}
+
+// PushFrontList inserts a copy of another list at the front of list l.
+// The lists l and other may be the same. They must not be nil.
+func (l *List) PushFrontList(other *List) {
+	l.lazyInit()
+	for i, e := other.Len(), other.Back(); i > 0; i, e = i-1, e.Prev() {
+		l.insertValue(e.Value, &l.root)
+	}
+}
diff --git a/contrib/go/_std_1.19/src/context/context.go b/contrib/go/_std_1.19/src/context/context.go
new file mode 100644
index 0000000000..1070111efa
--- /dev/null
+++ b/contrib/go/_std_1.19/src/context/context.go
@@ -0,0 +1,593 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package context defines the Context type, which carries deadlines,
+// cancellation signals, and other request-scoped values across API boundaries
+// and between processes.
+//
+// Incoming requests to a server should create a Context, and outgoing
+// calls to servers should accept a Context. The chain of function
+// calls between them must propagate the Context, optionally replacing
+// it with a derived Context created using WithCancel, WithDeadline,
+// WithTimeout, or WithValue. When a Context is canceled, all
+// Contexts derived from it are also canceled.
+//
+// The WithCancel, WithDeadline, and WithTimeout functions take a
+// Context (the parent) and return a derived Context (the child) and a
+// CancelFunc. Calling the CancelFunc cancels the child and its
+// children, removes the parent's reference to the child, and stops
+// any associated timers. Failing to call the CancelFunc leaks the
+// child and its children until the parent is canceled or the timer
+// fires. The go vet tool checks that CancelFuncs are used on all
+// control-flow paths.
+//
+// Programs that use Contexts should follow these rules to keep interfaces
+// consistent across packages and enable static analysis tools to check context
+// propagation:
+//
+// Do not store Contexts inside a struct type; instead, pass a Context
+// explicitly to each function that needs it. The Context should be the first
+// parameter, typically named ctx:
+//
+//	func DoSomething(ctx context.Context, arg Arg) error {
+//		// ... use ctx ...
+//	}
+//
+// Do not pass a nil Context, even if a function permits it. Pass context.TODO
+// if you are unsure about which Context to use.
+//
+// Use context Values only for request-scoped data that transits processes and
+// APIs, not for passing optional parameters to functions.
+//
+// The same Context may be passed to functions running in different goroutines;
+// Contexts are safe for simultaneous use by multiple goroutines.
+//
+// See https://blog.golang.org/context for example code for a server that uses
+// Contexts.
+package context
+
+import (
+	"errors"
+	"internal/reflectlite"
+	"sync"
+	"sync/atomic"
+	"time"
+)
+
+// A Context carries a deadline, a cancellation signal, and other values across
+// API boundaries.
+//
+// Context's methods may be called by multiple goroutines simultaneously.
+type Context interface {
+	// Deadline returns the time when work done on behalf of this context
+	// should be canceled. Deadline returns ok==false when no deadline is
+	// set. Successive calls to Deadline return the same results.
+	Deadline() (deadline time.Time, ok bool)
+
+	// Done returns a channel that's closed when work done on behalf of this
+	// context should be canceled. Done may return nil if this context can
+	// never be canceled. Successive calls to Done return the same value.
+	// The close of the Done channel may happen asynchronously,
+	// after the cancel function returns.
+	//
+	// WithCancel arranges for Done to be closed when cancel is called;
+	// WithDeadline arranges for Done to be closed when the deadline
+	// expires; WithTimeout arranges for Done to be closed when the timeout
+	// elapses.
+	//
+	// Done is provided for use in select statements:
+	//
+	//  // Stream generates values with DoSomething and sends them to out
+	//  // until DoSomething returns an error or ctx.Done is closed.
+	//  func Stream(ctx context.Context, out chan<- Value) error {
+	//  	for {
+	//  		v, err := DoSomething(ctx)
+	//  		if err != nil {
+	//  			return err
+	//  		}
+	//  		select {
+	//  		case <-ctx.Done():
+	//  			return ctx.Err()
+	//  		case out <- v:
+	//  		}
+	//  	}
+	//  }
+	//
+	// See https://blog.golang.org/pipelines for more examples of how to use
+	// a Done channel for cancellation.
+	Done() <-chan struct{}
+
+	// If Done is not yet closed, Err returns nil.
+	// If Done is closed, Err returns a non-nil error explaining why:
+	// Canceled if the context was canceled
+	// or DeadlineExceeded if the context's deadline passed.
+	// After Err returns a non-nil error, successive calls to Err return the same error.
+	Err() error
+
+	// Value returns the value associated with this context for key, or nil
+	// if no value is associated with key. Successive calls to Value with
+	// the same key returns the same result.
+	//
+	// Use context values only for request-scoped data that transits
+	// processes and API boundaries, not for passing optional parameters to
+	// functions.
+	//
+	// A key identifies a specific value in a Context. Functions that wish
+	// to store values in Context typically allocate a key in a global
+	// variable then use that key as the argument to context.WithValue and
+	// Context.Value. A key can be any type that supports equality;
+	// packages should define keys as an unexported type to avoid
+	// collisions.
+	//
+	// Packages that define a Context key should provide type-safe accessors
+	// for the values stored using that key:
+	//
+	// 	// Package user defines a User type that's stored in Contexts.
+	// 	package user
+	//
+	// 	import "context"
+	//
+	// 	// User is the type of value stored in the Contexts.
+	// 	type User struct {...}
+	//
+	// 	// key is an unexported type for keys defined in this package.
+	// 	// This prevents collisions with keys defined in other packages.
+	// 	type key int
+	//
+	// 	// userKey is the key for user.User values in Contexts. It is
+	// 	// unexported; clients use user.NewContext and user.FromContext
+	// 	// instead of using this key directly.
+	// 	var userKey key
+	//
+	// 	// NewContext returns a new Context that carries value u.
+	// 	func NewContext(ctx context.Context, u *User) context.Context {
+	// 		return context.WithValue(ctx, userKey, u)
+	// 	}
+	//
+	// 	// FromContext returns the User value stored in ctx, if any.
+	// 	func FromContext(ctx context.Context) (*User, bool) {
+	// 		u, ok := ctx.Value(userKey).(*User)
+	// 		return u, ok
+	// 	}
+	Value(key any) any
+}
+
+// Canceled is the error returned by Context.Err when the context is canceled.
+var Canceled = errors.New("context canceled")
+
+// DeadlineExceeded is the error returned by Context.Err when the context's
+// deadline passes.
+var DeadlineExceeded error = deadlineExceededError{}
+
+type deadlineExceededError struct{}
+
+func (deadlineExceededError) Error() string   { return "context deadline exceeded" }
+func (deadlineExceededError) Timeout() bool   { return true }
+func (deadlineExceededError) Temporary() bool { return true }
+
+// An emptyCtx is never canceled, has no values, and has no deadline. It is not
+// struct{}, since vars of this type must have distinct addresses.
+type emptyCtx int
+
+func (*emptyCtx) Deadline() (deadline time.Time, ok bool) {
+	return
+}
+
+func (*emptyCtx) Done() <-chan struct{} {
+	return nil
+}
+
+func (*emptyCtx) Err() error {
+	return nil
+}
+
+func (*emptyCtx) Value(key any) any {
+	return nil
+}
+
+func (e *emptyCtx) String() string {
+	switch e {
+	case background:
+		return "context.Background"
+	case todo:
+		return "context.TODO"
+	}
+	return "unknown empty Context"
+}
+
+var (
+	background = new(emptyCtx)
+	todo       = new(emptyCtx)
+)
+
+// Background returns a non-nil, empty Context. It is never canceled, has no
+// values, and has no deadline. It is typically used by the main function,
+// initialization, and tests, and as the top-level Context for incoming
+// requests.
+func Background() Context {
+	return background
+}
+
+// TODO returns a non-nil, empty Context. Code should use context.TODO when
+// it's unclear which Context to use or it is not yet available (because the
+// surrounding function has not yet been extended to accept a Context
+// parameter).
+func TODO() Context {
+	return todo
+}
+
+// A CancelFunc tells an operation to abandon its work.
+// A CancelFunc does not wait for the work to stop.
+// A CancelFunc may be called by multiple goroutines simultaneously.
+// After the first call, subsequent calls to a CancelFunc do nothing.
+type CancelFunc func()
+
+// WithCancel returns a copy of parent with a new Done channel. The returned
+// context's Done channel is closed when the returned cancel function is called
+// or when the parent context's Done channel is closed, whichever happens first.
+//
+// Canceling this context releases resources associated with it, so code should
+// call cancel as soon as the operations running in this Context complete.
+func WithCancel(parent Context) (ctx Context, cancel CancelFunc) {
+	if parent == nil {
+		panic("cannot create context from nil parent")
+	}
+	c := newCancelCtx(parent)
+	propagateCancel(parent, &c)
+	return &c, func() { c.cancel(true, Canceled) }
+}
+
+// newCancelCtx returns an initialized cancelCtx.
+func newCancelCtx(parent Context) cancelCtx {
+	return cancelCtx{Context: parent}
+}
+
+// goroutines counts the number of goroutines ever created; for testing.
+var goroutines int32
+
+// propagateCancel arranges for child to be canceled when parent is.
+func propagateCancel(parent Context, child canceler) {
+	done := parent.Done()
+	if done == nil {
+		return // parent is never canceled
+	}
+
+	select {
+	case <-done:
+		// parent is already canceled
+		child.cancel(false, parent.Err())
+		return
+	default:
+	}
+
+	if p, ok := parentCancelCtx(parent); ok {
+		p.mu.Lock()
+		if p.err != nil {
+			// parent has already been canceled
+			child.cancel(false, p.err)
+		} else {
+			if p.children == nil {
+				p.children = make(map[canceler]struct{})
+			}
+			p.children[child] = struct{}{}
+		}
+		p.mu.Unlock()
+	} else {
+		atomic.AddInt32(&goroutines, +1)
+		go func() {
+			select {
+			case <-parent.Done():
+				child.cancel(false, parent.Err())
+			case <-child.Done():
+			}
+		}()
+	}
+}
+
+// &cancelCtxKey is the key that a cancelCtx returns itself for.
+var cancelCtxKey int
+
+// parentCancelCtx returns the underlying *cancelCtx for parent.
+// It does this by looking up parent.Value(&cancelCtxKey) to find
+// the innermost enclosing *cancelCtx and then checking whether
+// parent.Done() matches that *cancelCtx. (If not, the *cancelCtx
+// has been wrapped in a custom implementation providing a
+// different done channel, in which case we should not bypass it.)
+func parentCancelCtx(parent Context) (*cancelCtx, bool) {
+	done := parent.Done()
+	if done == closedchan || done == nil {
+		return nil, false
+	}
+	p, ok := parent.Value(&cancelCtxKey).(*cancelCtx)
+	if !ok {
+		return nil, false
+	}
+	pdone, _ := p.done.Load().(chan struct{})
+	if pdone != done {
+		return nil, false
+	}
+	return p, true
+}
+
+// removeChild removes a context from its parent.
+func removeChild(parent Context, child canceler) {
+	p, ok := parentCancelCtx(parent)
+	if !ok {
+		return
+	}
+	p.mu.Lock()
+	if p.children != nil {
+		delete(p.children, child)
+	}
+	p.mu.Unlock()
+}
+
+// A canceler is a context type that can be canceled directly. The
+// implementations are *cancelCtx and *timerCtx.
+type canceler interface {
+	cancel(removeFromParent bool, err error)
+	Done() <-chan struct{}
+}
+
+// closedchan is a reusable closed channel.
+var closedchan = make(chan struct{})
+
+func init() {
+	close(closedchan)
+}
+
+// A cancelCtx can be canceled. When canceled, it also cancels any children
+// that implement canceler.
+type cancelCtx struct {
+	Context
+
+	mu       sync.Mutex            // protects following fields
+	done     atomic.Value          // of chan struct{}, created lazily, closed by first cancel call
+	children map[canceler]struct{} // set to nil by the first cancel call
+	err      error                 // set to non-nil by the first cancel call
+}
+
+func (c *cancelCtx) Value(key any) any {
+	if key == &cancelCtxKey {
+		return c
+	}
+	return value(c.Context, key)
+}
+
+func (c *cancelCtx) Done() <-chan struct{} {
+	d := c.done.Load()
+	if d != nil {
+		return d.(chan struct{})
+	}
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	d = c.done.Load()
+	if d == nil {
+		d = make(chan struct{})
+		c.done.Store(d)
+	}
+	return d.(chan struct{})
+}
+
+func (c *cancelCtx) Err() error {
+	c.mu.Lock()
+	err := c.err
+	c.mu.Unlock()
+	return err
+}
+
+type stringer interface {
+	String() string
+}
+
+func contextName(c Context) string {
+	if s, ok := c.(stringer); ok {
+		return s.String()
+	}
+	return reflectlite.TypeOf(c).String()
+}
+
+func (c *cancelCtx) String() string {
+	return contextName(c.Context) + ".WithCancel"
+}
+
+// cancel closes c.done, cancels each of c's children, and, if
+// removeFromParent is true, removes c from its parent's children.
+func (c *cancelCtx) cancel(removeFromParent bool, err error) {
+	if err == nil {
+		panic("context: internal error: missing cancel error")
+	}
+	c.mu.Lock()
+	if c.err != nil {
+		c.mu.Unlock()
+		return // already canceled
+	}
+	c.err = err
+	d, _ := c.done.Load().(chan struct{})
+	if d == nil {
+		c.done.Store(closedchan)
+	} else {
+		close(d)
+	}
+	for child := range c.children {
+		// NOTE: acquiring the child's lock while holding parent's lock.
+		child.cancel(false, err)
+	}
+	c.children = nil
+	c.mu.Unlock()
+
+	if removeFromParent {
+		removeChild(c.Context, c)
+	}
+}
+
+// WithDeadline returns a copy of the parent context with the deadline adjusted
+// to be no later than d. If the parent's deadline is already earlier than d,
+// WithDeadline(parent, d) is semantically equivalent to parent. The returned
+// context's Done channel is closed when the deadline expires, when the returned
+// cancel function is called, or when the parent context's Done channel is
+// closed, whichever happens first.
+//
+// Canceling this context releases resources associated with it, so code should
+// call cancel as soon as the operations running in this Context complete.
+func WithDeadline(parent Context, d time.Time) (Context, CancelFunc) {
+	if parent == nil {
+		panic("cannot create context from nil parent")
+	}
+	if cur, ok := parent.Deadline(); ok && cur.Before(d) {
+		// The current deadline is already sooner than the new one.
+		return WithCancel(parent)
+	}
+	c := &timerCtx{
+		cancelCtx: newCancelCtx(parent),
+		deadline:  d,
+	}
+	propagateCancel(parent, c)
+	dur := time.Until(d)
+	if dur <= 0 {
+		c.cancel(true, DeadlineExceeded) // deadline has already passed
+		return c, func() { c.cancel(false, Canceled) }
+	}
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	if c.err == nil {
+		c.timer = time.AfterFunc(dur, func() {
+			c.cancel(true, DeadlineExceeded)
+		})
+	}
+	return c, func() { c.cancel(true, Canceled) }
+}
+
+// A timerCtx carries a timer and a deadline. It embeds a cancelCtx to
+// implement Done and Err. It implements cancel by stopping its timer then
+// delegating to cancelCtx.cancel.
+type timerCtx struct {
+	cancelCtx
+	timer *time.Timer // Under cancelCtx.mu.
+
+	deadline time.Time
+}
+
+func (c *timerCtx) Deadline() (deadline time.Time, ok bool) {
+	return c.deadline, true
+}
+
+func (c *timerCtx) String() string {
+	return contextName(c.cancelCtx.Context) + ".WithDeadline(" +
+		c.deadline.String() + " [" +
+		time.Until(c.deadline).String() + "])"
+}
+
+func (c *timerCtx) cancel(removeFromParent bool, err error) {
+	c.cancelCtx.cancel(false, err)
+	if removeFromParent {
+		// Remove this timerCtx from its parent cancelCtx's children.
+		removeChild(c.cancelCtx.Context, c)
+	}
+	c.mu.Lock()
+	if c.timer != nil {
+		c.timer.Stop()
+		c.timer = nil
+	}
+	c.mu.Unlock()
+}
+
+// WithTimeout returns WithDeadline(parent, time.Now().Add(timeout)).
+//
+// Canceling this context releases resources associated with it, so code should
+// call cancel as soon as the operations running in this Context complete:
+//
+//	func slowOperationWithTimeout(ctx context.Context) (Result, error) {
+//		ctx, cancel := context.WithTimeout(ctx, 100*time.Millisecond)
+//		defer cancel()  // releases resources if slowOperation completes before timeout elapses
+//		return slowOperation(ctx)
+//	}
+func WithTimeout(parent Context, timeout time.Duration) (Context, CancelFunc) {
+	return WithDeadline(parent, time.Now().Add(timeout))
+}
+
+// WithValue returns a copy of parent in which the value associated with key is
+// val.
+//
+// Use context Values only for request-scoped data that transits processes and
+// APIs, not for passing optional parameters to functions.
+//
+// The provided key must be comparable and should not be of type
+// string or any other built-in type to avoid collisions between
+// packages using context. Users of WithValue should define their own
+// types for keys. To avoid allocating when assigning to an
+// interface{}, context keys often have concrete type
+// struct{}. Alternatively, exported context key variables' static
+// type should be a pointer or interface.
+func WithValue(parent Context, key, val any) Context {
+	if parent == nil {
+		panic("cannot create context from nil parent")
+	}
+	if key == nil {
+		panic("nil key")
+	}
+	if !reflectlite.TypeOf(key).Comparable() {
+		panic("key is not comparable")
+	}
+	return &valueCtx{parent, key, val}
+}
+
+// A valueCtx carries a key-value pair. It implements Value for that key and
+// delegates all other calls to the embedded Context.
+type valueCtx struct {
+	Context
+	key, val any
+}
+
+// stringify tries a bit to stringify v, without using fmt, since we don't
+// want context depending on the unicode tables. This is only used by
+// *valueCtx.String().
+func stringify(v any) string {
+	switch s := v.(type) {
+	case stringer:
+		return s.String()
+	case string:
+		return s
+	}
+	return "<not Stringer>"
+}
+
+func (c *valueCtx) String() string {
+	return contextName(c.Context) + ".WithValue(type " +
+		reflectlite.TypeOf(c.key).String() +
+		", val " + stringify(c.val) + ")"
+}
+
+func (c *valueCtx) Value(key any) any {
+	if c.key == key {
+		return c.val
+	}
+	return value(c.Context, key)
+}
+
+func value(c Context, key any) any {
+	for {
+		switch ctx := c.(type) {
+		case *valueCtx:
+			if key == ctx.key {
+				return ctx.val
+			}
+			c = ctx.Context
+		case *cancelCtx:
+			if key == &cancelCtxKey {
+				return c
+			}
+			c = ctx.Context
+		case *timerCtx:
+			if key == &cancelCtxKey {
+				return &ctx.cancelCtx
+			}
+			c = ctx.Context
+		case *emptyCtx:
+			return nil
+		default:
+			return c.Value(key)
+		}
+	}
+}
diff --git a/contrib/go/_std_1.19/src/crypto/aes/aes_gcm.go b/contrib/go/_std_1.19/src/crypto/aes/aes_gcm.go
new file mode 100644
index 0000000000..ebae646a13
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/aes/aes_gcm.go
@@ -0,0 +1,186 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build amd64 || arm64
+
+package aes
+
+import (
+	"crypto/cipher"
+	subtleoverlap "crypto/internal/subtle"
+	"crypto/subtle"
+	"errors"
+)
+
+// The following functions are defined in gcm_*.s.
+
+//go:noescape
+func gcmAesInit(productTable *[256]byte, ks []uint32)
+
+//go:noescape
+func gcmAesData(productTable *[256]byte, data []byte, T *[16]byte)
+
+//go:noescape
+func gcmAesEnc(productTable *[256]byte, dst, src []byte, ctr, T *[16]byte, ks []uint32)
+
+//go:noescape
+func gcmAesDec(productTable *[256]byte, dst, src []byte, ctr, T *[16]byte, ks []uint32)
+
+//go:noescape
+func gcmAesFinish(productTable *[256]byte, tagMask, T *[16]byte, pLen, dLen uint64)
+
+const (
+	gcmBlockSize         = 16
+	gcmTagSize           = 16
+	gcmMinimumTagSize    = 12 // NIST SP 800-38D recommends tags with 12 or more bytes.
+	gcmStandardNonceSize = 12
+)
+
+var errOpen = errors.New("cipher: message authentication failed")
+
+// Assert that aesCipherGCM implements the gcmAble interface.
+var _ gcmAble = (*aesCipherGCM)(nil)
+
+// NewGCM returns the AES cipher wrapped in Galois Counter Mode. This is only
+// called by crypto/cipher.NewGCM via the gcmAble interface.
+func (c *aesCipherGCM) NewGCM(nonceSize, tagSize int) (cipher.AEAD, error) {
+	g := &gcmAsm{ks: c.enc, nonceSize: nonceSize, tagSize: tagSize}
+	gcmAesInit(&g.productTable, g.ks)
+	return g, nil
+}
+
+type gcmAsm struct {
+	// ks is the key schedule, the length of which depends on the size of
+	// the AES key.
+	ks []uint32
+	// productTable contains pre-computed multiples of the binary-field
+	// element used in GHASH.
+	productTable [256]byte
+	// nonceSize contains the expected size of the nonce, in bytes.
+	nonceSize int
+	// tagSize contains the size of the tag, in bytes.
+	tagSize int
+}
+
+func (g *gcmAsm) NonceSize() int {
+	return g.nonceSize
+}
+
+func (g *gcmAsm) Overhead() int {
+	return g.tagSize
+}
+
+// sliceForAppend takes a slice and a requested number of bytes. It returns a
+// slice with the contents of the given slice followed by that many bytes and a
+// second slice that aliases into it and contains only the extra bytes. If the
+// original slice has sufficient capacity then no allocation is performed.
+func sliceForAppend(in []byte, n int) (head, tail []byte) {
+	if total := len(in) + n; cap(in) >= total {
+		head = in[:total]
+	} else {
+		head = make([]byte, total)
+		copy(head, in)
+	}
+	tail = head[len(in):]
+	return
+}
+
+// Seal encrypts and authenticates plaintext. See the cipher.AEAD interface for
+// details.
+func (g *gcmAsm) Seal(dst, nonce, plaintext, data []byte) []byte {
+	if len(nonce) != g.nonceSize {
+		panic("crypto/cipher: incorrect nonce length given to GCM")
+	}
+	if uint64(len(plaintext)) > ((1<<32)-2)*BlockSize {
+		panic("crypto/cipher: message too large for GCM")
+	}
+
+	var counter, tagMask [gcmBlockSize]byte
+
+	if len(nonce) == gcmStandardNonceSize {
+		// Init counter to nonce||1
+		copy(counter[:], nonce)
+		counter[gcmBlockSize-1] = 1
+	} else {
+		// Otherwise counter = GHASH(nonce)
+		gcmAesData(&g.productTable, nonce, &counter)
+		gcmAesFinish(&g.productTable, &tagMask, &counter, uint64(len(nonce)), uint64(0))
+	}
+
+	encryptBlockAsm(len(g.ks)/4-1, &g.ks[0], &tagMask[0], &counter[0])
+
+	var tagOut [gcmTagSize]byte
+	gcmAesData(&g.productTable, data, &tagOut)
+
+	ret, out := sliceForAppend(dst, len(plaintext)+g.tagSize)
+	if subtleoverlap.InexactOverlap(out[:len(plaintext)], plaintext) {
+		panic("crypto/cipher: invalid buffer overlap")
+	}
+	if len(plaintext) > 0 {
+		gcmAesEnc(&g.productTable, out, plaintext, &counter, &tagOut, g.ks)
+	}
+	gcmAesFinish(&g.productTable, &tagMask, &tagOut, uint64(len(plaintext)), uint64(len(data)))
+	copy(out[len(plaintext):], tagOut[:])
+
+	return ret
+}
+
+// Open authenticates and decrypts ciphertext. See the cipher.AEAD interface
+// for details.
+func (g *gcmAsm) Open(dst, nonce, ciphertext, data []byte) ([]byte, error) {
+	if len(nonce) != g.nonceSize {
+		panic("crypto/cipher: incorrect nonce length given to GCM")
+	}
+	// Sanity check to prevent the authentication from always succeeding if an implementation
+	// leaves tagSize uninitialized, for example.
+	if g.tagSize < gcmMinimumTagSize {
+		panic("crypto/cipher: incorrect GCM tag size")
+	}
+
+	if len(ciphertext) < g.tagSize {
+		return nil, errOpen
+	}
+	if uint64(len(ciphertext)) > ((1<<32)-2)*uint64(BlockSize)+uint64(g.tagSize) {
+		return nil, errOpen
+	}
+
+	tag := ciphertext[len(ciphertext)-g.tagSize:]
+	ciphertext = ciphertext[:len(ciphertext)-g.tagSize]
+
+	// See GCM spec, section 7.1.
+	var counter, tagMask [gcmBlockSize]byte
+
+	if len(nonce) == gcmStandardNonceSize {
+		// Init counter to nonce||1
+		copy(counter[:], nonce)
+		counter[gcmBlockSize-1] = 1
+	} else {
+		// Otherwise counter = GHASH(nonce)
+		gcmAesData(&g.productTable, nonce, &counter)
+		gcmAesFinish(&g.productTable, &tagMask, &counter, uint64(len(nonce)), uint64(0))
+	}
+
+	encryptBlockAsm(len(g.ks)/4-1, &g.ks[0], &tagMask[0], &counter[0])
+
+	var expectedTag [gcmTagSize]byte
+	gcmAesData(&g.productTable, data, &expectedTag)
+
+	ret, out := sliceForAppend(dst, len(ciphertext))
+	if subtleoverlap.InexactOverlap(out, ciphertext) {
+		panic("crypto/cipher: invalid buffer overlap")
+	}
+	if len(ciphertext) > 0 {
+		gcmAesDec(&g.productTable, out, ciphertext, &counter, &expectedTag, g.ks)
+	}
+	gcmAesFinish(&g.productTable, &tagMask, &expectedTag, uint64(len(ciphertext)), uint64(len(data)))
+
+	if subtle.ConstantTimeCompare(expectedTag[:g.tagSize], tag) != 1 {
+		for i := range out {
+			out[i] = 0
+		}
+		return nil, errOpen
+	}
+
+	return ret, nil
+}
diff --git a/contrib/go/_std_1.18/src/crypto/aes/asm_amd64.s b/contrib/go/_std_1.19/src/crypto/aes/asm_amd64.s
index ed831bf47f..ed831bf47f 100644
--- a/contrib/go/_std_1.18/src/crypto/aes/asm_amd64.s
+++ b/contrib/go/_std_1.19/src/crypto/aes/asm_amd64.s
diff --git a/contrib/go/_std_1.18/src/crypto/aes/block.go b/contrib/go/_std_1.19/src/crypto/aes/block.go
index 53308ae92e..53308ae92e 100644
--- a/contrib/go/_std_1.18/src/crypto/aes/block.go
+++ b/contrib/go/_std_1.19/src/crypto/aes/block.go
diff --git a/contrib/go/_std_1.19/src/crypto/aes/cipher.go b/contrib/go/_std_1.19/src/crypto/aes/cipher.go
new file mode 100644
index 0000000000..db0ee38b78
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/aes/cipher.go
@@ -0,0 +1,82 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package aes
+
+import (
+	"crypto/cipher"
+	"crypto/internal/boring"
+	"crypto/internal/subtle"
+	"strconv"
+)
+
+// The AES block size in bytes.
+const BlockSize = 16
+
+// A cipher is an instance of AES encryption using a particular key.
+type aesCipher struct {
+	enc []uint32
+	dec []uint32
+}
+
+type KeySizeError int
+
+func (k KeySizeError) Error() string {
+	return "crypto/aes: invalid key size " + strconv.Itoa(int(k))
+}
+
+// NewCipher creates and returns a new cipher.Block.
+// The key argument should be the AES key,
+// either 16, 24, or 32 bytes to select
+// AES-128, AES-192, or AES-256.
+func NewCipher(key []byte) (cipher.Block, error) {
+	k := len(key)
+	switch k {
+	default:
+		return nil, KeySizeError(k)
+	case 16, 24, 32:
+		break
+	}
+	if boring.Enabled {
+		return boring.NewAESCipher(key)
+	}
+	return newCipher(key)
+}
+
+// newCipherGeneric creates and returns a new cipher.Block
+// implemented in pure Go.
+func newCipherGeneric(key []byte) (cipher.Block, error) {
+	n := len(key) + 28
+	c := aesCipher{make([]uint32, n), make([]uint32, n)}
+	expandKeyGo(key, c.enc, c.dec)
+	return &c, nil
+}
+
+func (c *aesCipher) BlockSize() int { return BlockSize }
+
+func (c *aesCipher) Encrypt(dst, src []byte) {
+	if len(src) < BlockSize {
+		panic("crypto/aes: input not full block")
+	}
+	if len(dst) < BlockSize {
+		panic("crypto/aes: output not full block")
+	}
+	if subtle.InexactOverlap(dst[:BlockSize], src[:BlockSize]) {
+		panic("crypto/aes: invalid buffer overlap")
+	}
+	encryptBlockGo(c.enc, dst, src)
+}
+
+func (c *aesCipher) Decrypt(dst, src []byte) {
+	if len(src) < BlockSize {
+		panic("crypto/aes: input not full block")
+	}
+	if len(dst) < BlockSize {
+		panic("crypto/aes: output not full block")
+	}
+	if subtle.InexactOverlap(dst[:BlockSize], src[:BlockSize]) {
+		panic("crypto/aes: invalid buffer overlap")
+	}
+	decryptBlockGo(c.dec, dst, src)
+}
diff --git a/contrib/go/_std_1.19/src/crypto/aes/cipher_asm.go b/contrib/go/_std_1.19/src/crypto/aes/cipher_asm.go
new file mode 100644
index 0000000000..1482b22d08
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/aes/cipher_asm.go
@@ -0,0 +1,113 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build amd64 || arm64 || ppc64 || ppc64le
+
+package aes
+
+import (
+	"crypto/cipher"
+	"crypto/internal/boring"
+	"crypto/internal/subtle"
+	"internal/cpu"
+	"internal/goarch"
+)
+
+// defined in asm_*.s
+
+//go:noescape
+func encryptBlockAsm(nr int, xk *uint32, dst, src *byte)
+
+//go:noescape
+func decryptBlockAsm(nr int, xk *uint32, dst, src *byte)
+
+//go:noescape
+func expandKeyAsm(nr int, key *byte, enc *uint32, dec *uint32)
+
+type aesCipherAsm struct {
+	aesCipher
+}
+
+// aesCipherGCM implements crypto/cipher.gcmAble so that crypto/cipher.NewGCM
+// will use the optimised implementation in aes_gcm.go when possible.
+// Instances of this type only exist when hasGCMAsm returns true. Likewise,
+// the gcmAble implementation is in aes_gcm.go.
+type aesCipherGCM struct {
+	aesCipherAsm
+}
+
+var supportsAES = cpu.X86.HasAES || cpu.ARM64.HasAES || goarch.IsPpc64 == 1 || goarch.IsPpc64le == 1
+var supportsGFMUL = cpu.X86.HasPCLMULQDQ || cpu.ARM64.HasPMULL
+
+func newCipher(key []byte) (cipher.Block, error) {
+	if !supportsAES {
+		return newCipherGeneric(key)
+	}
+	n := len(key) + 28
+	c := aesCipherAsm{aesCipher{make([]uint32, n), make([]uint32, n)}}
+	var rounds int
+	switch len(key) {
+	case 128 / 8:
+		rounds = 10
+	case 192 / 8:
+		rounds = 12
+	case 256 / 8:
+		rounds = 14
+	default:
+		return nil, KeySizeError(len(key))
+	}
+
+	expandKeyAsm(rounds, &key[0], &c.enc[0], &c.dec[0])
+	if supportsAES && supportsGFMUL {
+		return &aesCipherGCM{c}, nil
+	}
+	return &c, nil
+}
+
+func (c *aesCipherAsm) BlockSize() int { return BlockSize }
+
+func (c *aesCipherAsm) Encrypt(dst, src []byte) {
+	boring.Unreachable()
+	if len(src) < BlockSize {
+		panic("crypto/aes: input not full block")
+	}
+	if len(dst) < BlockSize {
+		panic("crypto/aes: output not full block")
+	}
+	if subtle.InexactOverlap(dst[:BlockSize], src[:BlockSize]) {
+		panic("crypto/aes: invalid buffer overlap")
+	}
+	encryptBlockAsm(len(c.enc)/4-1, &c.enc[0], &dst[0], &src[0])
+}
+
+func (c *aesCipherAsm) Decrypt(dst, src []byte) {
+	boring.Unreachable()
+	if len(src) < BlockSize {
+		panic("crypto/aes: input not full block")
+	}
+	if len(dst) < BlockSize {
+		panic("crypto/aes: output not full block")
+	}
+	if subtle.InexactOverlap(dst[:BlockSize], src[:BlockSize]) {
+		panic("crypto/aes: invalid buffer overlap")
+	}
+	decryptBlockAsm(len(c.dec)/4-1, &c.dec[0], &dst[0], &src[0])
+}
+
+// expandKey is used by BenchmarkExpand to ensure that the asm implementation
+// of key expansion is used for the benchmark when it is available.
+func expandKey(key []byte, enc, dec []uint32) {
+	if supportsAES {
+		rounds := 10 // rounds needed for AES128
+		switch len(key) {
+		case 192 / 8:
+			rounds = 12
+		case 256 / 8:
+			rounds = 14
+		}
+		expandKeyAsm(rounds, &key[0], &enc[0], &dec[0])
+	} else {
+		expandKeyGo(key, enc, dec)
+	}
+}
diff --git a/contrib/go/_std_1.18/src/crypto/aes/const.go b/contrib/go/_std_1.19/src/crypto/aes/const.go
index 4eca4b9aff..4eca4b9aff 100644
--- a/contrib/go/_std_1.18/src/crypto/aes/const.go
+++ b/contrib/go/_std_1.19/src/crypto/aes/const.go
diff --git a/contrib/go/_std_1.18/src/crypto/aes/gcm_amd64.s b/contrib/go/_std_1.19/src/crypto/aes/gcm_amd64.s
index e6eedf3264..e6eedf3264 100644
--- a/contrib/go/_std_1.18/src/crypto/aes/gcm_amd64.s
+++ b/contrib/go/_std_1.19/src/crypto/aes/gcm_amd64.s
diff --git a/contrib/go/_std_1.18/src/crypto/aes/modes.go b/contrib/go/_std_1.19/src/crypto/aes/modes.go
index 5c0b08eb6d..5c0b08eb6d 100644
--- a/contrib/go/_std_1.18/src/crypto/aes/modes.go
+++ b/contrib/go/_std_1.19/src/crypto/aes/modes.go
diff --git a/contrib/go/_std_1.19/src/crypto/cipher/cbc.go b/contrib/go/_std_1.19/src/crypto/cipher/cbc.go
new file mode 100644
index 0000000000..a719b61e24
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/cipher/cbc.go
@@ -0,0 +1,185 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Cipher block chaining (CBC) mode.
+
+// CBC provides confidentiality by xoring (chaining) each plaintext block
+// with the previous ciphertext block before applying the block cipher.
+
+// See NIST SP 800-38A, pp 10-11
+
+package cipher
+
+import "crypto/internal/subtle"
+
+type cbc struct {
+	b         Block
+	blockSize int
+	iv        []byte
+	tmp       []byte
+}
+
+func newCBC(b Block, iv []byte) *cbc {
+	return &cbc{
+		b:         b,
+		blockSize: b.BlockSize(),
+		iv:        dup(iv),
+		tmp:       make([]byte, b.BlockSize()),
+	}
+}
+
+type cbcEncrypter cbc
+
+// cbcEncAble is an interface implemented by ciphers that have a specific
+// optimized implementation of CBC encryption, like crypto/aes.
+// NewCBCEncrypter will check for this interface and return the specific
+// BlockMode if found.
+type cbcEncAble interface {
+	NewCBCEncrypter(iv []byte) BlockMode
+}
+
+// NewCBCEncrypter returns a BlockMode which encrypts in cipher block chaining
+// mode, using the given Block. The length of iv must be the same as the
+// Block's block size.
+func NewCBCEncrypter(b Block, iv []byte) BlockMode {
+	if len(iv) != b.BlockSize() {
+		panic("cipher.NewCBCEncrypter: IV length must equal block size")
+	}
+	if cbc, ok := b.(cbcEncAble); ok {
+		return cbc.NewCBCEncrypter(iv)
+	}
+	return (*cbcEncrypter)(newCBC(b, iv))
+}
+
+// newCBCGenericEncrypter returns a BlockMode which encrypts in cipher block chaining
+// mode, using the given Block. The length of iv must be the same as the
+// Block's block size. This always returns the generic non-asm encrypter for use
+// in fuzz testing.
+func newCBCGenericEncrypter(b Block, iv []byte) BlockMode {
+	if len(iv) != b.BlockSize() {
+		panic("cipher.NewCBCEncrypter: IV length must equal block size")
+	}
+	return (*cbcEncrypter)(newCBC(b, iv))
+}
+
+func (x *cbcEncrypter) BlockSize() int { return x.blockSize }
+
+func (x *cbcEncrypter) CryptBlocks(dst, src []byte) {
+	if len(src)%x.blockSize != 0 {
+		panic("crypto/cipher: input not full blocks")
+	}
+	if len(dst) < len(src) {
+		panic("crypto/cipher: output smaller than input")
+	}
+	if subtle.InexactOverlap(dst[:len(src)], src) {
+		panic("crypto/cipher: invalid buffer overlap")
+	}
+
+	iv := x.iv
+
+	for len(src) > 0 {
+		// Write the xor to dst, then encrypt in place.
+		xorBytes(dst[:x.blockSize], src[:x.blockSize], iv)
+		x.b.Encrypt(dst[:x.blockSize], dst[:x.blockSize])
+
+		// Move to the next block with this block as the next iv.
+		iv = dst[:x.blockSize]
+		src = src[x.blockSize:]
+		dst = dst[x.blockSize:]
+	}
+
+	// Save the iv for the next CryptBlocks call.
+	copy(x.iv, iv)
+}
+
+func (x *cbcEncrypter) SetIV(iv []byte) {
+	if len(iv) != len(x.iv) {
+		panic("cipher: incorrect length IV")
+	}
+	copy(x.iv, iv)
+}
+
+type cbcDecrypter cbc
+
+// cbcDecAble is an interface implemented by ciphers that have a specific
+// optimized implementation of CBC decryption, like crypto/aes.
+// NewCBCDecrypter will check for this interface and return the specific
+// BlockMode if found.
+type cbcDecAble interface {
+	NewCBCDecrypter(iv []byte) BlockMode
+}
+
+// NewCBCDecrypter returns a BlockMode which decrypts in cipher block chaining
+// mode, using the given Block. The length of iv must be the same as the
+// Block's block size and must match the iv used to encrypt the data.
+func NewCBCDecrypter(b Block, iv []byte) BlockMode {
+	if len(iv) != b.BlockSize() {
+		panic("cipher.NewCBCDecrypter: IV length must equal block size")
+	}
+	if cbc, ok := b.(cbcDecAble); ok {
+		return cbc.NewCBCDecrypter(iv)
+	}
+	return (*cbcDecrypter)(newCBC(b, iv))
+}
+
+// newCBCGenericDecrypter returns a BlockMode which encrypts in cipher block chaining
+// mode, using the given Block. The length of iv must be the same as the
+// Block's block size. This always returns the generic non-asm decrypter for use in
+// fuzz testing.
+func newCBCGenericDecrypter(b Block, iv []byte) BlockMode {
+	if len(iv) != b.BlockSize() {
+		panic("cipher.NewCBCDecrypter: IV length must equal block size")
+	}
+	return (*cbcDecrypter)(newCBC(b, iv))
+}
+
+func (x *cbcDecrypter) BlockSize() int { return x.blockSize }
+
+func (x *cbcDecrypter) CryptBlocks(dst, src []byte) {
+	if len(src)%x.blockSize != 0 {
+		panic("crypto/cipher: input not full blocks")
+	}
+	if len(dst) < len(src) {
+		panic("crypto/cipher: output smaller than input")
+	}
+	if subtle.InexactOverlap(dst[:len(src)], src) {
+		panic("crypto/cipher: invalid buffer overlap")
+	}
+	if len(src) == 0 {
+		return
+	}
+
+	// For each block, we need to xor the decrypted data with the previous block's ciphertext (the iv).
+	// To avoid making a copy each time, we loop over the blocks BACKWARDS.
+	end := len(src)
+	start := end - x.blockSize
+	prev := start - x.blockSize
+
+	// Copy the last block of ciphertext in preparation as the new iv.
+	copy(x.tmp, src[start:end])
+
+	// Loop over all but the first block.
+	for start > 0 {
+		x.b.Decrypt(dst[start:end], src[start:end])
+		xorBytes(dst[start:end], dst[start:end], src[prev:start])
+
+		end = start
+		start = prev
+		prev -= x.blockSize
+	}
+
+	// The first block is special because it uses the saved iv.
+	x.b.Decrypt(dst[start:end], src[start:end])
+	xorBytes(dst[start:end], dst[start:end], x.iv)
+
+	// Set the new iv to the first block we copied earlier.
+	x.iv, x.tmp = x.tmp, x.iv
+}
+
+func (x *cbcDecrypter) SetIV(iv []byte) {
+	if len(iv) != len(x.iv) {
+		panic("cipher: incorrect length IV")
+	}
+	copy(x.iv, iv)
+}
diff --git a/contrib/go/_std_1.18/src/crypto/cipher/cfb.go b/contrib/go/_std_1.19/src/crypto/cipher/cfb.go
index 80c9bc24ea..80c9bc24ea 100644
--- a/contrib/go/_std_1.18/src/crypto/cipher/cfb.go
+++ b/contrib/go/_std_1.19/src/crypto/cipher/cfb.go
diff --git a/contrib/go/_std_1.18/src/crypto/cipher/cipher.go b/contrib/go/_std_1.19/src/crypto/cipher/cipher.go
index 7e1a4de9a3..7e1a4de9a3 100644
--- a/contrib/go/_std_1.18/src/crypto/cipher/cipher.go
+++ b/contrib/go/_std_1.19/src/crypto/cipher/cipher.go
diff --git a/contrib/go/_std_1.18/src/crypto/cipher/ctr.go b/contrib/go/_std_1.19/src/crypto/cipher/ctr.go
index cba028d2a4..cba028d2a4 100644
--- a/contrib/go/_std_1.18/src/crypto/cipher/ctr.go
+++ b/contrib/go/_std_1.19/src/crypto/cipher/ctr.go
diff --git a/contrib/go/_std_1.19/src/crypto/cipher/gcm.go b/contrib/go/_std_1.19/src/crypto/cipher/gcm.go
new file mode 100644
index 0000000000..5b14c0a7e2
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/cipher/gcm.go
@@ -0,0 +1,427 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cipher
+
+import (
+	subtleoverlap "crypto/internal/subtle"
+	"crypto/subtle"
+	"encoding/binary"
+	"errors"
+)
+
+// AEAD is a cipher mode providing authenticated encryption with associated
+// data. For a description of the methodology, see
+// https://en.wikipedia.org/wiki/Authenticated_encryption.
+type AEAD interface {
+	// NonceSize returns the size of the nonce that must be passed to Seal
+	// and Open.
+	NonceSize() int
+
+	// Overhead returns the maximum difference between the lengths of a
+	// plaintext and its ciphertext.
+	Overhead() int
+
+	// Seal encrypts and authenticates plaintext, authenticates the
+	// additional data and appends the result to dst, returning the updated
+	// slice. The nonce must be NonceSize() bytes long and unique for all
+	// time, for a given key.
+	//
+	// To reuse plaintext's storage for the encrypted output, use plaintext[:0]
+	// as dst. Otherwise, the remaining capacity of dst must not overlap plaintext.
+	Seal(dst, nonce, plaintext, additionalData []byte) []byte
+
+	// Open decrypts and authenticates ciphertext, authenticates the
+	// additional data and, if successful, appends the resulting plaintext
+	// to dst, returning the updated slice. The nonce must be NonceSize()
+	// bytes long and both it and the additional data must match the
+	// value passed to Seal.
+	//
+	// To reuse ciphertext's storage for the decrypted output, use ciphertext[:0]
+	// as dst. Otherwise, the remaining capacity of dst must not overlap plaintext.
+	//
+	// Even if the function fails, the contents of dst, up to its capacity,
+	// may be overwritten.
+	Open(dst, nonce, ciphertext, additionalData []byte) ([]byte, error)
+}
+
+// gcmAble is an interface implemented by ciphers that have a specific optimized
+// implementation of GCM, like crypto/aes. NewGCM will check for this interface
+// and return the specific AEAD if found.
+type gcmAble interface {
+	NewGCM(nonceSize, tagSize int) (AEAD, error)
+}
+
+// gcmFieldElement represents a value in GF(2¹²⁸). In order to reflect the GCM
+// standard and make binary.BigEndian suitable for marshaling these values, the
+// bits are stored in big endian order. For example:
+//
+//	the coefficient of x⁰ can be obtained by v.low >> 63.
+//	the coefficient of x⁶³ can be obtained by v.low & 1.
+//	the coefficient of x⁶⁴ can be obtained by v.high >> 63.
+//	the coefficient of x¹²⁷ can be obtained by v.high & 1.
+type gcmFieldElement struct {
+	low, high uint64
+}
+
+// gcm represents a Galois Counter Mode with a specific key. See
+// https://csrc.nist.gov/groups/ST/toolkit/BCM/documents/proposedmodes/gcm/gcm-revised-spec.pdf
+type gcm struct {
+	cipher    Block
+	nonceSize int
+	tagSize   int
+	// productTable contains the first sixteen powers of the key, H.
+	// However, they are in bit reversed order. See NewGCMWithNonceSize.
+	productTable [16]gcmFieldElement
+}
+
+// NewGCM returns the given 128-bit, block cipher wrapped in Galois Counter Mode
+// with the standard nonce length.
+//
+// In general, the GHASH operation performed by this implementation of GCM is not constant-time.
+// An exception is when the underlying Block was created by aes.NewCipher
+// on systems with hardware support for AES. See the crypto/aes package documentation for details.
+func NewGCM(cipher Block) (AEAD, error) {
+	return newGCMWithNonceAndTagSize(cipher, gcmStandardNonceSize, gcmTagSize)
+}
+
+// NewGCMWithNonceSize returns the given 128-bit, block cipher wrapped in Galois
+// Counter Mode, which accepts nonces of the given length. The length must not
+// be zero.
+//
+// Only use this function if you require compatibility with an existing
+// cryptosystem that uses non-standard nonce lengths. All other users should use
+// NewGCM, which is faster and more resistant to misuse.
+func NewGCMWithNonceSize(cipher Block, size int) (AEAD, error) {
+	return newGCMWithNonceAndTagSize(cipher, size, gcmTagSize)
+}
+
+// NewGCMWithTagSize returns the given 128-bit, block cipher wrapped in Galois
+// Counter Mode, which generates tags with the given length.
+//
+// Tag sizes between 12 and 16 bytes are allowed.
+//
+// Only use this function if you require compatibility with an existing
+// cryptosystem that uses non-standard tag lengths. All other users should use
+// NewGCM, which is more resistant to misuse.
+func NewGCMWithTagSize(cipher Block, tagSize int) (AEAD, error) {
+	return newGCMWithNonceAndTagSize(cipher, gcmStandardNonceSize, tagSize)
+}
+
+func newGCMWithNonceAndTagSize(cipher Block, nonceSize, tagSize int) (AEAD, error) {
+	if tagSize < gcmMinimumTagSize || tagSize > gcmBlockSize {
+		return nil, errors.New("cipher: incorrect tag size given to GCM")
+	}
+
+	if nonceSize <= 0 {
+		return nil, errors.New("cipher: the nonce can't have zero length, or the security of the key will be immediately compromised")
+	}
+
+	if cipher, ok := cipher.(gcmAble); ok {
+		return cipher.NewGCM(nonceSize, tagSize)
+	}
+
+	if cipher.BlockSize() != gcmBlockSize {
+		return nil, errors.New("cipher: NewGCM requires 128-bit block cipher")
+	}
+
+	var key [gcmBlockSize]byte
+	cipher.Encrypt(key[:], key[:])
+
+	g := &gcm{cipher: cipher, nonceSize: nonceSize, tagSize: tagSize}
+
+	// We precompute 16 multiples of |key|. However, when we do lookups
+	// into this table we'll be using bits from a field element and
+	// therefore the bits will be in the reverse order. So normally one
+	// would expect, say, 4*key to be in index 4 of the table but due to
+	// this bit ordering it will actually be in index 0010 (base 2) = 2.
+	x := gcmFieldElement{
+		binary.BigEndian.Uint64(key[:8]),
+		binary.BigEndian.Uint64(key[8:]),
+	}
+	g.productTable[reverseBits(1)] = x
+
+	for i := 2; i < 16; i += 2 {
+		g.productTable[reverseBits(i)] = gcmDouble(&g.productTable[reverseBits(i/2)])
+		g.productTable[reverseBits(i+1)] = gcmAdd(&g.productTable[reverseBits(i)], &x)
+	}
+
+	return g, nil
+}
+
+const (
+	gcmBlockSize         = 16
+	gcmTagSize           = 16
+	gcmMinimumTagSize    = 12 // NIST SP 800-38D recommends tags with 12 or more bytes.
+	gcmStandardNonceSize = 12
+)
+
+func (g *gcm) NonceSize() int {
+	return g.nonceSize
+}
+
+func (g *gcm) Overhead() int {
+	return g.tagSize
+}
+
+func (g *gcm) Seal(dst, nonce, plaintext, data []byte) []byte {
+	if len(nonce) != g.nonceSize {
+		panic("crypto/cipher: incorrect nonce length given to GCM")
+	}
+	if uint64(len(plaintext)) > ((1<<32)-2)*uint64(g.cipher.BlockSize()) {
+		panic("crypto/cipher: message too large for GCM")
+	}
+
+	ret, out := sliceForAppend(dst, len(plaintext)+g.tagSize)
+	if subtleoverlap.InexactOverlap(out, plaintext) {
+		panic("crypto/cipher: invalid buffer overlap")
+	}
+
+	var counter, tagMask [gcmBlockSize]byte
+	g.deriveCounter(&counter, nonce)
+
+	g.cipher.Encrypt(tagMask[:], counter[:])
+	gcmInc32(&counter)
+
+	g.counterCrypt(out, plaintext, &counter)
+
+	var tag [gcmTagSize]byte
+	g.auth(tag[:], out[:len(plaintext)], data, &tagMask)
+	copy(out[len(plaintext):], tag[:])
+
+	return ret
+}
+
+var errOpen = errors.New("cipher: message authentication failed")
+
+func (g *gcm) Open(dst, nonce, ciphertext, data []byte) ([]byte, error) {
+	if len(nonce) != g.nonceSize {
+		panic("crypto/cipher: incorrect nonce length given to GCM")
+	}
+	// Sanity check to prevent the authentication from always succeeding if an implementation
+	// leaves tagSize uninitialized, for example.
+	if g.tagSize < gcmMinimumTagSize {
+		panic("crypto/cipher: incorrect GCM tag size")
+	}
+
+	if len(ciphertext) < g.tagSize {
+		return nil, errOpen
+	}
+	if uint64(len(ciphertext)) > ((1<<32)-2)*uint64(g.cipher.BlockSize())+uint64(g.tagSize) {
+		return nil, errOpen
+	}
+
+	tag := ciphertext[len(ciphertext)-g.tagSize:]
+	ciphertext = ciphertext[:len(ciphertext)-g.tagSize]
+
+	var counter, tagMask [gcmBlockSize]byte
+	g.deriveCounter(&counter, nonce)
+
+	g.cipher.Encrypt(tagMask[:], counter[:])
+	gcmInc32(&counter)
+
+	var expectedTag [gcmTagSize]byte
+	g.auth(expectedTag[:], ciphertext, data, &tagMask)
+
+	ret, out := sliceForAppend(dst, len(ciphertext))
+	if subtleoverlap.InexactOverlap(out, ciphertext) {
+		panic("crypto/cipher: invalid buffer overlap")
+	}
+
+	if subtle.ConstantTimeCompare(expectedTag[:g.tagSize], tag) != 1 {
+		// The AESNI code decrypts and authenticates concurrently, and
+		// so overwrites dst in the event of a tag mismatch. That
+		// behavior is mimicked here in order to be consistent across
+		// platforms.
+		for i := range out {
+			out[i] = 0
+		}
+		return nil, errOpen
+	}
+
+	g.counterCrypt(out, ciphertext, &counter)
+
+	return ret, nil
+}
+
+// reverseBits reverses the order of the bits of 4-bit number in i.
+func reverseBits(i int) int {
+	i = ((i << 2) & 0xc) | ((i >> 2) & 0x3)
+	i = ((i << 1) & 0xa) | ((i >> 1) & 0x5)
+	return i
+}
+
+// gcmAdd adds two elements of GF(2¹²⁸) and returns the sum.
+func gcmAdd(x, y *gcmFieldElement) gcmFieldElement {
+	// Addition in a characteristic 2 field is just XOR.
+	return gcmFieldElement{x.low ^ y.low, x.high ^ y.high}
+}
+
+// gcmDouble returns the result of doubling an element of GF(2¹²⁸).
+func gcmDouble(x *gcmFieldElement) (double gcmFieldElement) {
+	msbSet := x.high&1 == 1
+
+	// Because of the bit-ordering, doubling is actually a right shift.
+	double.high = x.high >> 1
+	double.high |= x.low << 63
+	double.low = x.low >> 1
+
+	// If the most-significant bit was set before shifting then it,
+	// conceptually, becomes a term of x^128. This is greater than the
+	// irreducible polynomial so the result has to be reduced. The
+	// irreducible polynomial is 1+x+x^2+x^7+x^128. We can subtract that to
+	// eliminate the term at x^128 which also means subtracting the other
+	// four terms. In characteristic 2 fields, subtraction == addition ==
+	// XOR.
+	if msbSet {
+		double.low ^= 0xe100000000000000
+	}
+
+	return
+}
+
+var gcmReductionTable = []uint16{
+	0x0000, 0x1c20, 0x3840, 0x2460, 0x7080, 0x6ca0, 0x48c0, 0x54e0,
+	0xe100, 0xfd20, 0xd940, 0xc560, 0x9180, 0x8da0, 0xa9c0, 0xb5e0,
+}
+
+// mul sets y to y*H, where H is the GCM key, fixed during NewGCMWithNonceSize.
+func (g *gcm) mul(y *gcmFieldElement) {
+	var z gcmFieldElement
+
+	for i := 0; i < 2; i++ {
+		word := y.high
+		if i == 1 {
+			word = y.low
+		}
+
+		// Multiplication works by multiplying z by 16 and adding in
+		// one of the precomputed multiples of H.
+		for j := 0; j < 64; j += 4 {
+			msw := z.high & 0xf
+			z.high >>= 4
+			z.high |= z.low << 60
+			z.low >>= 4
+			z.low ^= uint64(gcmReductionTable[msw]) << 48
+
+			// the values in |table| are ordered for
+			// little-endian bit positions. See the comment
+			// in NewGCMWithNonceSize.
+			t := &g.productTable[word&0xf]
+
+			z.low ^= t.low
+			z.high ^= t.high
+			word >>= 4
+		}
+	}
+
+	*y = z
+}
+
+// updateBlocks extends y with more polynomial terms from blocks, based on
+// Horner's rule. There must be a multiple of gcmBlockSize bytes in blocks.
+func (g *gcm) updateBlocks(y *gcmFieldElement, blocks []byte) {
+	for len(blocks) > 0 {
+		y.low ^= binary.BigEndian.Uint64(blocks)
+		y.high ^= binary.BigEndian.Uint64(blocks[8:])
+		g.mul(y)
+		blocks = blocks[gcmBlockSize:]
+	}
+}
+
+// update extends y with more polynomial terms from data. If data is not a
+// multiple of gcmBlockSize bytes long then the remainder is zero padded.
+func (g *gcm) update(y *gcmFieldElement, data []byte) {
+	fullBlocks := (len(data) >> 4) << 4
+	g.updateBlocks(y, data[:fullBlocks])
+
+	if len(data) != fullBlocks {
+		var partialBlock [gcmBlockSize]byte
+		copy(partialBlock[:], data[fullBlocks:])
+		g.updateBlocks(y, partialBlock[:])
+	}
+}
+
+// gcmInc32 treats the final four bytes of counterBlock as a big-endian value
+// and increments it.
+func gcmInc32(counterBlock *[16]byte) {
+	ctr := counterBlock[len(counterBlock)-4:]
+	binary.BigEndian.PutUint32(ctr, binary.BigEndian.Uint32(ctr)+1)
+}
+
+// sliceForAppend takes a slice and a requested number of bytes. It returns a
+// slice with the contents of the given slice followed by that many bytes and a
+// second slice that aliases into it and contains only the extra bytes. If the
+// original slice has sufficient capacity then no allocation is performed.
+func sliceForAppend(in []byte, n int) (head, tail []byte) {
+	if total := len(in) + n; cap(in) >= total {
+		head = in[:total]
+	} else {
+		head = make([]byte, total)
+		copy(head, in)
+	}
+	tail = head[len(in):]
+	return
+}
+
+// counterCrypt crypts in to out using g.cipher in counter mode.
+func (g *gcm) counterCrypt(out, in []byte, counter *[gcmBlockSize]byte) {
+	var mask [gcmBlockSize]byte
+
+	for len(in) >= gcmBlockSize {
+		g.cipher.Encrypt(mask[:], counter[:])
+		gcmInc32(counter)
+
+		xorWords(out, in, mask[:])
+		out = out[gcmBlockSize:]
+		in = in[gcmBlockSize:]
+	}
+
+	if len(in) > 0 {
+		g.cipher.Encrypt(mask[:], counter[:])
+		gcmInc32(counter)
+		xorBytes(out, in, mask[:])
+	}
+}
+
+// deriveCounter computes the initial GCM counter state from the given nonce.
+// See NIST SP 800-38D, section 7.1. This assumes that counter is filled with
+// zeros on entry.
+func (g *gcm) deriveCounter(counter *[gcmBlockSize]byte, nonce []byte) {
+	// GCM has two modes of operation with respect to the initial counter
+	// state: a "fast path" for 96-bit (12-byte) nonces, and a "slow path"
+	// for nonces of other lengths. For a 96-bit nonce, the nonce, along
+	// with a four-byte big-endian counter starting at one, is used
+	// directly as the starting counter. For other nonce sizes, the counter
+	// is computed by passing it through the GHASH function.
+	if len(nonce) == gcmStandardNonceSize {
+		copy(counter[:], nonce)
+		counter[gcmBlockSize-1] = 1
+	} else {
+		var y gcmFieldElement
+		g.update(&y, nonce)
+		y.high ^= uint64(len(nonce)) * 8
+		g.mul(&y)
+		binary.BigEndian.PutUint64(counter[:8], y.low)
+		binary.BigEndian.PutUint64(counter[8:], y.high)
+	}
+}
+
+// auth calculates GHASH(ciphertext, additionalData), masks the result with
+// tagMask and writes the result to out.
+func (g *gcm) auth(out, ciphertext, additionalData []byte, tagMask *[gcmTagSize]byte) {
+	var y gcmFieldElement
+	g.update(&y, additionalData)
+	g.update(&y, ciphertext)
+
+	y.low ^= uint64(len(additionalData)) * 8
+	y.high ^= uint64(len(ciphertext)) * 8
+
+	g.mul(&y)
+
+	binary.BigEndian.PutUint64(out, y.low)
+	binary.BigEndian.PutUint64(out[8:], y.high)
+
+	xorWords(out, out, tagMask[:])
+}
diff --git a/contrib/go/_std_1.18/src/crypto/cipher/io.go b/contrib/go/_std_1.19/src/crypto/cipher/io.go
index 0974ac748e..0974ac748e 100644
--- a/contrib/go/_std_1.18/src/crypto/cipher/io.go
+++ b/contrib/go/_std_1.19/src/crypto/cipher/io.go
diff --git a/contrib/go/_std_1.18/src/crypto/cipher/ofb.go b/contrib/go/_std_1.19/src/crypto/cipher/ofb.go
index fc47724865..fc47724865 100644
--- a/contrib/go/_std_1.18/src/crypto/cipher/ofb.go
+++ b/contrib/go/_std_1.19/src/crypto/cipher/ofb.go
diff --git a/contrib/go/_std_1.18/src/crypto/cipher/xor_amd64.go b/contrib/go/_std_1.19/src/crypto/cipher/xor_amd64.go
index a595acc017..a595acc017 100644
--- a/contrib/go/_std_1.18/src/crypto/cipher/xor_amd64.go
+++ b/contrib/go/_std_1.19/src/crypto/cipher/xor_amd64.go
diff --git a/contrib/go/_std_1.18/src/crypto/cipher/xor_amd64.s b/contrib/go/_std_1.19/src/crypto/cipher/xor_amd64.s
index 780d37a06e..780d37a06e 100644
--- a/contrib/go/_std_1.18/src/crypto/cipher/xor_amd64.s
+++ b/contrib/go/_std_1.19/src/crypto/cipher/xor_amd64.s
diff --git a/contrib/go/_std_1.19/src/crypto/crypto.go b/contrib/go/_std_1.19/src/crypto/crypto.go
new file mode 100644
index 0000000000..10a1cd8403
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/crypto.go
@@ -0,0 +1,223 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package crypto collects common cryptographic constants.
+package crypto
+
+import (
+	"hash"
+	"io"
+	"strconv"
+)
+
+// Hash identifies a cryptographic hash function that is implemented in another
+// package.
+type Hash uint
+
+// HashFunc simply returns the value of h so that Hash implements SignerOpts.
+func (h Hash) HashFunc() Hash {
+	return h
+}
+
+func (h Hash) String() string {
+	switch h {
+	case MD4:
+		return "MD4"
+	case MD5:
+		return "MD5"
+	case SHA1:
+		return "SHA-1"
+	case SHA224:
+		return "SHA-224"
+	case SHA256:
+		return "SHA-256"
+	case SHA384:
+		return "SHA-384"
+	case SHA512:
+		return "SHA-512"
+	case MD5SHA1:
+		return "MD5+SHA1"
+	case RIPEMD160:
+		return "RIPEMD-160"
+	case SHA3_224:
+		return "SHA3-224"
+	case SHA3_256:
+		return "SHA3-256"
+	case SHA3_384:
+		return "SHA3-384"
+	case SHA3_512:
+		return "SHA3-512"
+	case SHA512_224:
+		return "SHA-512/224"
+	case SHA512_256:
+		return "SHA-512/256"
+	case BLAKE2s_256:
+		return "BLAKE2s-256"
+	case BLAKE2b_256:
+		return "BLAKE2b-256"
+	case BLAKE2b_384:
+		return "BLAKE2b-384"
+	case BLAKE2b_512:
+		return "BLAKE2b-512"
+	default:
+		return "unknown hash value " + strconv.Itoa(int(h))
+	}
+}
+
+const (
+	MD4         Hash = 1 + iota // import golang.org/x/crypto/md4
+	MD5                         // import crypto/md5
+	SHA1                        // import crypto/sha1
+	SHA224                      // import crypto/sha256
+	SHA256                      // import crypto/sha256
+	SHA384                      // import crypto/sha512
+	SHA512                      // import crypto/sha512
+	MD5SHA1                     // no implementation; MD5+SHA1 used for TLS RSA
+	RIPEMD160                   // import golang.org/x/crypto/ripemd160
+	SHA3_224                    // import golang.org/x/crypto/sha3
+	SHA3_256                    // import golang.org/x/crypto/sha3
+	SHA3_384                    // import golang.org/x/crypto/sha3
+	SHA3_512                    // import golang.org/x/crypto/sha3
+	SHA512_224                  // import crypto/sha512
+	SHA512_256                  // import crypto/sha512
+	BLAKE2s_256                 // import golang.org/x/crypto/blake2s
+	BLAKE2b_256                 // import golang.org/x/crypto/blake2b
+	BLAKE2b_384                 // import golang.org/x/crypto/blake2b
+	BLAKE2b_512                 // import golang.org/x/crypto/blake2b
+	maxHash
+)
+
+var digestSizes = []uint8{
+	MD4:         16,
+	MD5:         16,
+	SHA1:        20,
+	SHA224:      28,
+	SHA256:      32,
+	SHA384:      48,
+	SHA512:      64,
+	SHA512_224:  28,
+	SHA512_256:  32,
+	SHA3_224:    28,
+	SHA3_256:    32,
+	SHA3_384:    48,
+	SHA3_512:    64,
+	MD5SHA1:     36,
+	RIPEMD160:   20,
+	BLAKE2s_256: 32,
+	BLAKE2b_256: 32,
+	BLAKE2b_384: 48,
+	BLAKE2b_512: 64,
+}
+
+// Size returns the length, in bytes, of a digest resulting from the given hash
+// function. It doesn't require that the hash function in question be linked
+// into the program.
+func (h Hash) Size() int {
+	if h > 0 && h < maxHash {
+		return int(digestSizes[h])
+	}
+	panic("crypto: Size of unknown hash function")
+}
+
+var hashes = make([]func() hash.Hash, maxHash)
+
+// New returns a new hash.Hash calculating the given hash function. New panics
+// if the hash function is not linked into the binary.
+func (h Hash) New() hash.Hash {
+	if h > 0 && h < maxHash {
+		f := hashes[h]
+		if f != nil {
+			return f()
+		}
+	}
+	panic("crypto: requested hash function #" + strconv.Itoa(int(h)) + " is unavailable")
+}
+
+// Available reports whether the given hash function is linked into the binary.
+func (h Hash) Available() bool {
+	return h < maxHash && hashes[h] != nil
+}
+
+// RegisterHash registers a function that returns a new instance of the given
+// hash function. This is intended to be called from the init function in
+// packages that implement hash functions.
+func RegisterHash(h Hash, f func() hash.Hash) {
+	if h >= maxHash {
+		panic("crypto: RegisterHash of unknown hash function")
+	}
+	hashes[h] = f
+}
+
+// PublicKey represents a public key using an unspecified algorithm.
+//
+// Although this type is an empty interface for backwards compatibility reasons,
+// all public key types in the standard library implement the following interface
+//
+//	interface{
+//	    Equal(x crypto.PublicKey) bool
+//	}
+//
+// which can be used for increased type safety within applications.
+type PublicKey any
+
+// PrivateKey represents a private key using an unspecified algorithm.
+//
+// Although this type is an empty interface for backwards compatibility reasons,
+// all private key types in the standard library implement the following interface
+//
+//	interface{
+//	    Public() crypto.PublicKey
+//	    Equal(x crypto.PrivateKey) bool
+//	}
+//
+// as well as purpose-specific interfaces such as Signer and Decrypter, which
+// can be used for increased type safety within applications.
+type PrivateKey any
+
+// Signer is an interface for an opaque private key that can be used for
+// signing operations. For example, an RSA key kept in a hardware module.
+type Signer interface {
+	// Public returns the public key corresponding to the opaque,
+	// private key.
+	Public() PublicKey
+
+	// Sign signs digest with the private key, possibly using entropy from
+	// rand. For an RSA key, the resulting signature should be either a
+	// PKCS #1 v1.5 or PSS signature (as indicated by opts). For an (EC)DSA
+	// key, it should be a DER-serialised, ASN.1 signature structure.
+	//
+	// Hash implements the SignerOpts interface and, in most cases, one can
+	// simply pass in the hash function used as opts. Sign may also attempt
+	// to type assert opts to other types in order to obtain algorithm
+	// specific values. See the documentation in each package for details.
+	//
+	// Note that when a signature of a hash of a larger message is needed,
+	// the caller is responsible for hashing the larger message and passing
+	// the hash (as digest) and the hash function (as opts) to Sign.
+	Sign(rand io.Reader, digest []byte, opts SignerOpts) (signature []byte, err error)
+}
+
+// SignerOpts contains options for signing with a Signer.
+type SignerOpts interface {
+	// HashFunc returns an identifier for the hash function used to produce
+	// the message passed to Signer.Sign, or else zero to indicate that no
+	// hashing was done.
+	HashFunc() Hash
+}
+
+// Decrypter is an interface for an opaque private key that can be used for
+// asymmetric decryption operations. An example would be an RSA key
+// kept in a hardware module.
+type Decrypter interface {
+	// Public returns the public key corresponding to the opaque,
+	// private key.
+	Public() PublicKey
+
+	// Decrypt decrypts msg. The opts argument should be appropriate for
+	// the primitive used. See the documentation in each implementation for
+	// details.
+	Decrypt(rand io.Reader, msg []byte, opts DecrypterOpts) (plaintext []byte, err error)
+}
+
+type DecrypterOpts any
diff --git a/contrib/go/_std_1.19/src/crypto/des/block.go b/contrib/go/_std_1.19/src/crypto/des/block.go
new file mode 100644
index 0000000000..c649dee94f
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/des/block.go
@@ -0,0 +1,259 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package des
+
+import (
+	"encoding/binary"
+	"sync"
+)
+
+func cryptBlock(subkeys []uint64, dst, src []byte, decrypt bool) {
+	b := binary.BigEndian.Uint64(src)
+	b = permuteInitialBlock(b)
+	left, right := uint32(b>>32), uint32(b)
+
+	left = (left << 1) | (left >> 31)
+	right = (right << 1) | (right >> 31)
+
+	if decrypt {
+		for i := 0; i < 8; i++ {
+			left, right = feistel(left, right, subkeys[15-2*i], subkeys[15-(2*i+1)])
+		}
+	} else {
+		for i := 0; i < 8; i++ {
+			left, right = feistel(left, right, subkeys[2*i], subkeys[2*i+1])
+		}
+	}
+
+	left = (left << 31) | (left >> 1)
+	right = (right << 31) | (right >> 1)
+
+	// switch left & right and perform final permutation
+	preOutput := (uint64(right) << 32) | uint64(left)
+	binary.BigEndian.PutUint64(dst, permuteFinalBlock(preOutput))
+}
+
+// Encrypt one block from src into dst, using the subkeys.
+func encryptBlock(subkeys []uint64, dst, src []byte) {
+	cryptBlock(subkeys, dst, src, false)
+}
+
+// Decrypt one block from src into dst, using the subkeys.
+func decryptBlock(subkeys []uint64, dst, src []byte) {
+	cryptBlock(subkeys, dst, src, true)
+}
+
+// DES Feistel function. feistelBox must be initialized via
+// feistelBoxOnce.Do(initFeistelBox) first.
+func feistel(l, r uint32, k0, k1 uint64) (lout, rout uint32) {
+	var t uint32
+
+	t = r ^ uint32(k0>>32)
+	l ^= feistelBox[7][t&0x3f] ^
+		feistelBox[5][(t>>8)&0x3f] ^
+		feistelBox[3][(t>>16)&0x3f] ^
+		feistelBox[1][(t>>24)&0x3f]
+
+	t = ((r << 28) | (r >> 4)) ^ uint32(k0)
+	l ^= feistelBox[6][(t)&0x3f] ^
+		feistelBox[4][(t>>8)&0x3f] ^
+		feistelBox[2][(t>>16)&0x3f] ^
+		feistelBox[0][(t>>24)&0x3f]
+
+	t = l ^ uint32(k1>>32)
+	r ^= feistelBox[7][t&0x3f] ^
+		feistelBox[5][(t>>8)&0x3f] ^
+		feistelBox[3][(t>>16)&0x3f] ^
+		feistelBox[1][(t>>24)&0x3f]
+
+	t = ((l << 28) | (l >> 4)) ^ uint32(k1)
+	r ^= feistelBox[6][(t)&0x3f] ^
+		feistelBox[4][(t>>8)&0x3f] ^
+		feistelBox[2][(t>>16)&0x3f] ^
+		feistelBox[0][(t>>24)&0x3f]
+
+	return l, r
+}
+
+// feistelBox[s][16*i+j] contains the output of permutationFunction
+// for sBoxes[s][i][j] << 4*(7-s)
+var feistelBox [8][64]uint32
+
+var feistelBoxOnce sync.Once
+
+// general purpose function to perform DES block permutations
+func permuteBlock(src uint64, permutation []uint8) (block uint64) {
+	for position, n := range permutation {
+		bit := (src >> n) & 1
+		block |= bit << uint((len(permutation)-1)-position)
+	}
+	return
+}
+
+func initFeistelBox() {
+	for s := range sBoxes {
+		for i := 0; i < 4; i++ {
+			for j := 0; j < 16; j++ {
+				f := uint64(sBoxes[s][i][j]) << (4 * (7 - uint(s)))
+				f = permuteBlock(f, permutationFunction[:])
+
+				// Row is determined by the 1st and 6th bit.
+				// Column is the middle four bits.
+				row := uint8(((i & 2) << 4) | i&1)
+				col := uint8(j << 1)
+				t := row | col
+
+				// The rotation was performed in the feistel rounds, being factored out and now mixed into the feistelBox.
+				f = (f << 1) | (f >> 31)
+
+				feistelBox[s][t] = uint32(f)
+			}
+		}
+	}
+}
+
+// permuteInitialBlock is equivalent to the permutation defined
+// by initialPermutation.
+func permuteInitialBlock(block uint64) uint64 {
+	// block = b7 b6 b5 b4 b3 b2 b1 b0 (8 bytes)
+	b1 := block >> 48
+	b2 := block << 48
+	block ^= b1 ^ b2 ^ b1<<48 ^ b2>>48
+
+	// block = b1 b0 b5 b4 b3 b2 b7 b6
+	b1 = block >> 32 & 0xff00ff
+	b2 = (block & 0xff00ff00)
+	block ^= b1<<32 ^ b2 ^ b1<<8 ^ b2<<24 // exchange b0 b4 with b3 b7
+
+	// block is now b1 b3 b5 b7 b0 b2 b4 b6, the permutation:
+	//                  ...  8
+	//                  ... 24
+	//                  ... 40
+	//                  ... 56
+	//  7  6  5  4  3  2  1  0
+	// 23 22 21 20 19 18 17 16
+	//                  ... 32
+	//                  ... 48
+
+	// exchange 4,5,6,7 with 32,33,34,35 etc.
+	b1 = block & 0x0f0f00000f0f0000
+	b2 = block & 0x0000f0f00000f0f0
+	block ^= b1 ^ b2 ^ b1>>12 ^ b2<<12
+
+	// block is the permutation:
+	//
+	//   [+8]         [+40]
+	//
+	//  7  6  5  4
+	// 23 22 21 20
+	//  3  2  1  0
+	// 19 18 17 16    [+32]
+
+	// exchange 0,1,4,5 with 18,19,22,23
+	b1 = block & 0x3300330033003300
+	b2 = block & 0x00cc00cc00cc00cc
+	block ^= b1 ^ b2 ^ b1>>6 ^ b2<<6
+
+	// block is the permutation:
+	// 15 14
+	// 13 12
+	// 11 10
+	//  9  8
+	//  7  6
+	//  5  4
+	//  3  2
+	//  1  0 [+16] [+32] [+64]
+
+	// exchange 0,2,4,6 with 9,11,13,15:
+	b1 = block & 0xaaaaaaaa55555555
+	block ^= b1 ^ b1>>33 ^ b1<<33
+
+	// block is the permutation:
+	// 6 14 22 30 38 46 54 62
+	// 4 12 20 28 36 44 52 60
+	// 2 10 18 26 34 42 50 58
+	// 0  8 16 24 32 40 48 56
+	// 7 15 23 31 39 47 55 63
+	// 5 13 21 29 37 45 53 61
+	// 3 11 19 27 35 43 51 59
+	// 1  9 17 25 33 41 49 57
+	return block
+}
+
+// permuteInitialBlock is equivalent to the permutation defined
+// by finalPermutation.
+func permuteFinalBlock(block uint64) uint64 {
+	// Perform the same bit exchanges as permuteInitialBlock
+	// but in reverse order.
+	b1 := block & 0xaaaaaaaa55555555
+	block ^= b1 ^ b1>>33 ^ b1<<33
+
+	b1 = block & 0x3300330033003300
+	b2 := block & 0x00cc00cc00cc00cc
+	block ^= b1 ^ b2 ^ b1>>6 ^ b2<<6
+
+	b1 = block & 0x0f0f00000f0f0000
+	b2 = block & 0x0000f0f00000f0f0
+	block ^= b1 ^ b2 ^ b1>>12 ^ b2<<12
+
+	b1 = block >> 32 & 0xff00ff
+	b2 = (block & 0xff00ff00)
+	block ^= b1<<32 ^ b2 ^ b1<<8 ^ b2<<24
+
+	b1 = block >> 48
+	b2 = block << 48
+	block ^= b1 ^ b2 ^ b1<<48 ^ b2>>48
+	return block
+}
+
+// creates 16 28-bit blocks rotated according
+// to the rotation schedule
+func ksRotate(in uint32) (out []uint32) {
+	out = make([]uint32, 16)
+	last := in
+	for i := 0; i < 16; i++ {
+		// 28-bit circular left shift
+		left := (last << (4 + ksRotations[i])) >> 4
+		right := (last << 4) >> (32 - ksRotations[i])
+		out[i] = left | right
+		last = out[i]
+	}
+	return
+}
+
+// creates 16 56-bit subkeys from the original key
+func (c *desCipher) generateSubkeys(keyBytes []byte) {
+	feistelBoxOnce.Do(initFeistelBox)
+
+	// apply PC1 permutation to key
+	key := binary.BigEndian.Uint64(keyBytes)
+	permutedKey := permuteBlock(key, permutedChoice1[:])
+
+	// rotate halves of permuted key according to the rotation schedule
+	leftRotations := ksRotate(uint32(permutedKey >> 28))
+	rightRotations := ksRotate(uint32(permutedKey<<4) >> 4)
+
+	// generate subkeys
+	for i := 0; i < 16; i++ {
+		// combine halves to form 56-bit input to PC2
+		pc2Input := uint64(leftRotations[i])<<28 | uint64(rightRotations[i])
+		// apply PC2 permutation to 7 byte input
+		c.subkeys[i] = unpack(permuteBlock(pc2Input, permutedChoice2[:]))
+	}
+}
+
+// Expand 48-bit input to 64-bit, with each 6-bit block padded by extra two bits at the top.
+// By doing so, we can have the input blocks (four bits each), and the key blocks (six bits each) well-aligned without
+// extra shifts/rotations for alignments.
+func unpack(x uint64) uint64 {
+	return ((x>>(6*1))&0xff)<<(8*0) |
+		((x>>(6*3))&0xff)<<(8*1) |
+		((x>>(6*5))&0xff)<<(8*2) |
+		((x>>(6*7))&0xff)<<(8*3) |
+		((x>>(6*0))&0xff)<<(8*4) |
+		((x>>(6*2))&0xff)<<(8*5) |
+		((x>>(6*4))&0xff)<<(8*6) |
+		((x>>(6*6))&0xff)<<(8*7)
+}
diff --git a/contrib/go/_std_1.18/src/crypto/des/cipher.go b/contrib/go/_std_1.19/src/crypto/des/cipher.go
index 9e6779c216..9e6779c216 100644
--- a/contrib/go/_std_1.18/src/crypto/des/cipher.go
+++ b/contrib/go/_std_1.19/src/crypto/des/cipher.go
diff --git a/contrib/go/_std_1.18/src/crypto/des/const.go b/contrib/go/_std_1.19/src/crypto/des/const.go
index a20879d574..a20879d574 100644
--- a/contrib/go/_std_1.18/src/crypto/des/const.go
+++ b/contrib/go/_std_1.19/src/crypto/des/const.go
diff --git a/contrib/go/_std_1.18/src/crypto/dsa/dsa.go b/contrib/go/_std_1.19/src/crypto/dsa/dsa.go
index a83359996d..a83359996d 100644
--- a/contrib/go/_std_1.18/src/crypto/dsa/dsa.go
+++ b/contrib/go/_std_1.19/src/crypto/dsa/dsa.go
diff --git a/contrib/go/_std_1.19/src/crypto/ecdsa/ecdsa.go b/contrib/go/_std_1.19/src/crypto/ecdsa/ecdsa.go
new file mode 100644
index 0000000000..d0e52ad864
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/ecdsa/ecdsa.go
@@ -0,0 +1,427 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package ecdsa implements the Elliptic Curve Digital Signature Algorithm, as
+// defined in FIPS 186-4 and SEC 1, Version 2.0.
+//
+// Signatures generated by this package are not deterministic, but entropy is
+// mixed with the private key and the message, achieving the same level of
+// security in case of randomness source failure.
+package ecdsa
+
+// [FIPS 186-4] references ANSI X9.62-2005 for the bulk of the ECDSA algorithm.
+// That standard is not freely available, which is a problem in an open source
+// implementation, because not only the implementer, but also any maintainer,
+// contributor, reviewer, auditor, and learner needs access to it. Instead, this
+// package references and follows the equivalent [SEC 1, Version 2.0].
+//
+// [FIPS 186-4]: https://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.186-4.pdf
+// [SEC 1, Version 2.0]: https://www.secg.org/sec1-v2.pdf
+
+import (
+	"crypto"
+	"crypto/aes"
+	"crypto/cipher"
+	"crypto/elliptic"
+	"crypto/internal/boring"
+	"crypto/internal/boring/bbig"
+	"crypto/internal/randutil"
+	"crypto/sha512"
+	"errors"
+	"io"
+	"math/big"
+
+	"golang.org/x/crypto/cryptobyte"
+	"golang.org/x/crypto/cryptobyte/asn1"
+)
+
+// A invertible implements fast inverse in GF(N).
+type invertible interface {
+	// Inverse returns the inverse of k mod Params().N.
+	Inverse(k *big.Int) *big.Int
+}
+
+// A combinedMult implements fast combined multiplication for verification.
+type combinedMult interface {
+	// CombinedMult returns [s1]G + [s2]P where G is the generator.
+	CombinedMult(Px, Py *big.Int, s1, s2 []byte) (x, y *big.Int)
+}
+
+const (
+	aesIV = "IV for ECDSA CTR"
+)
+
+// PublicKey represents an ECDSA public key.
+type PublicKey struct {
+	elliptic.Curve
+	X, Y *big.Int
+}
+
+// Any methods implemented on PublicKey might need to also be implemented on
+// PrivateKey, as the latter embeds the former and will expose its methods.
+
+// Equal reports whether pub and x have the same value.
+//
+// Two keys are only considered to have the same value if they have the same Curve value.
+// Note that for example elliptic.P256() and elliptic.P256().Params() are different
+// values, as the latter is a generic not constant time implementation.
+func (pub *PublicKey) Equal(x crypto.PublicKey) bool {
+	xx, ok := x.(*PublicKey)
+	if !ok {
+		return false
+	}
+	return pub.X.Cmp(xx.X) == 0 && pub.Y.Cmp(xx.Y) == 0 &&
+		// Standard library Curve implementations are singletons, so this check
+		// will work for those. Other Curves might be equivalent even if not
+		// singletons, but there is no definitive way to check for that, and
+		// better to err on the side of safety.
+		pub.Curve == xx.Curve
+}
+
+// PrivateKey represents an ECDSA private key.
+type PrivateKey struct {
+	PublicKey
+	D *big.Int
+}
+
+// Public returns the public key corresponding to priv.
+func (priv *PrivateKey) Public() crypto.PublicKey {
+	return &priv.PublicKey
+}
+
+// Equal reports whether priv and x have the same value.
+//
+// See PublicKey.Equal for details on how Curve is compared.
+func (priv *PrivateKey) Equal(x crypto.PrivateKey) bool {
+	xx, ok := x.(*PrivateKey)
+	if !ok {
+		return false
+	}
+	return priv.PublicKey.Equal(&xx.PublicKey) && priv.D.Cmp(xx.D) == 0
+}
+
+// Sign signs digest with priv, reading randomness from rand. The opts argument
+// is not currently used but, in keeping with the crypto.Signer interface,
+// should be the hash function used to digest the message.
+//
+// This method implements crypto.Signer, which is an interface to support keys
+// where the private part is kept in, for example, a hardware module. Common
+// uses can use the SignASN1 function in this package directly.
+func (priv *PrivateKey) Sign(rand io.Reader, digest []byte, opts crypto.SignerOpts) ([]byte, error) {
+	if boring.Enabled && rand == boring.RandReader {
+		b, err := boringPrivateKey(priv)
+		if err != nil {
+			return nil, err
+		}
+		return boring.SignMarshalECDSA(b, digest)
+	}
+	boring.UnreachableExceptTests()
+
+	r, s, err := Sign(rand, priv, digest)
+	if err != nil {
+		return nil, err
+	}
+
+	var b cryptobyte.Builder
+	b.AddASN1(asn1.SEQUENCE, func(b *cryptobyte.Builder) {
+		b.AddASN1BigInt(r)
+		b.AddASN1BigInt(s)
+	})
+	return b.Bytes()
+}
+
+var one = new(big.Int).SetInt64(1)
+
+// randFieldElement returns a random element of the order of the given
+// curve using the procedure given in FIPS 186-4, Appendix B.5.1.
+func randFieldElement(c elliptic.Curve, rand io.Reader) (k *big.Int, err error) {
+	params := c.Params()
+	// Note that for P-521 this will actually be 63 bits more than the order, as
+	// division rounds down, but the extra bit is inconsequential.
+	b := make([]byte, params.N.BitLen()/8+8)
+	_, err = io.ReadFull(rand, b)
+	if err != nil {
+		return
+	}
+
+	k = new(big.Int).SetBytes(b)
+	n := new(big.Int).Sub(params.N, one)
+	k.Mod(k, n)
+	k.Add(k, one)
+	return
+}
+
+// GenerateKey generates a public and private key pair.
+func GenerateKey(c elliptic.Curve, rand io.Reader) (*PrivateKey, error) {
+	if boring.Enabled && rand == boring.RandReader {
+		x, y, d, err := boring.GenerateKeyECDSA(c.Params().Name)
+		if err != nil {
+			return nil, err
+		}
+		return &PrivateKey{PublicKey: PublicKey{Curve: c, X: bbig.Dec(x), Y: bbig.Dec(y)}, D: bbig.Dec(d)}, nil
+	}
+	boring.UnreachableExceptTests()
+
+	k, err := randFieldElement(c, rand)
+	if err != nil {
+		return nil, err
+	}
+
+	priv := new(PrivateKey)
+	priv.PublicKey.Curve = c
+	priv.D = k
+	priv.PublicKey.X, priv.PublicKey.Y = c.ScalarBaseMult(k.Bytes())
+	return priv, nil
+}
+
+// hashToInt converts a hash value to an integer. Per FIPS 186-4, Section 6.4,
+// we use the left-most bits of the hash to match the bit-length of the order of
+// the curve. This also performs Step 5 of SEC 1, Version 2.0, Section 4.1.3.
+func hashToInt(hash []byte, c elliptic.Curve) *big.Int {
+	orderBits := c.Params().N.BitLen()
+	orderBytes := (orderBits + 7) / 8
+	if len(hash) > orderBytes {
+		hash = hash[:orderBytes]
+	}
+
+	ret := new(big.Int).SetBytes(hash)
+	excess := len(hash)*8 - orderBits
+	if excess > 0 {
+		ret.Rsh(ret, uint(excess))
+	}
+	return ret
+}
+
+// fermatInverse calculates the inverse of k in GF(P) using Fermat's method
+// (exponentiation modulo P - 2, per Euler's theorem). This has better
+// constant-time properties than Euclid's method (implemented in
+// math/big.Int.ModInverse and FIPS 186-4, Appendix C.1) although math/big
+// itself isn't strictly constant-time so it's not perfect.
+func fermatInverse(k, N *big.Int) *big.Int {
+	two := big.NewInt(2)
+	nMinus2 := new(big.Int).Sub(N, two)
+	return new(big.Int).Exp(k, nMinus2, N)
+}
+
+var errZeroParam = errors.New("zero parameter")
+
+// Sign signs a hash (which should be the result of hashing a larger message)
+// using the private key, priv. If the hash is longer than the bit-length of the
+// private key's curve order, the hash will be truncated to that length. It
+// returns the signature as a pair of integers. Most applications should use
+// SignASN1 instead of dealing directly with r, s.
+func Sign(rand io.Reader, priv *PrivateKey, hash []byte) (r, s *big.Int, err error) {
+	randutil.MaybeReadByte(rand)
+
+	if boring.Enabled && rand == boring.RandReader {
+		b, err := boringPrivateKey(priv)
+		if err != nil {
+			return nil, nil, err
+		}
+		sig, err := boring.SignMarshalECDSA(b, hash)
+		if err != nil {
+			return nil, nil, err
+		}
+		var r, s big.Int
+		var inner cryptobyte.String
+		input := cryptobyte.String(sig)
+		if !input.ReadASN1(&inner, asn1.SEQUENCE) ||
+			!input.Empty() ||
+			!inner.ReadASN1Integer(&r) ||
+			!inner.ReadASN1Integer(&s) ||
+			!inner.Empty() {
+			return nil, nil, errors.New("invalid ASN.1 from boringcrypto")
+		}
+		return &r, &s, nil
+	}
+	boring.UnreachableExceptTests()
+
+	// This implementation derives the nonce from an AES-CTR CSPRNG keyed by:
+	//
+	//    SHA2-512(priv.D || entropy || hash)[:32]
+	//
+	// The CSPRNG key is indifferentiable from a random oracle as shown in
+	// [Coron], the AES-CTR stream is indifferentiable from a random oracle
+	// under standard cryptographic assumptions (see [Larsson] for examples).
+	//
+	// [Coron]: https://cs.nyu.edu/~dodis/ps/merkle.pdf
+	// [Larsson]: https://web.archive.org/web/20040719170906/https://www.nada.kth.se/kurser/kth/2D1441/semteo03/lecturenotes/assump.pdf
+
+	// Get 256 bits of entropy from rand.
+	entropy := make([]byte, 32)
+	_, err = io.ReadFull(rand, entropy)
+	if err != nil {
+		return
+	}
+
+	// Initialize an SHA-512 hash context; digest...
+	md := sha512.New()
+	md.Write(priv.D.Bytes()) // the private key,
+	md.Write(entropy)        // the entropy,
+	md.Write(hash)           // and the input hash;
+	key := md.Sum(nil)[:32]  // and compute ChopMD-256(SHA-512),
+	// which is an indifferentiable MAC.
+
+	// Create an AES-CTR instance to use as a CSPRNG.
+	block, err := aes.NewCipher(key)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// Create a CSPRNG that xors a stream of zeros with
+	// the output of the AES-CTR instance.
+	csprng := &cipher.StreamReader{
+		R: zeroReader,
+		S: cipher.NewCTR(block, []byte(aesIV)),
+	}
+
+	c := priv.PublicKey.Curve
+	return sign(priv, csprng, c, hash)
+}
+
+func signGeneric(priv *PrivateKey, csprng *cipher.StreamReader, c elliptic.Curve, hash []byte) (r, s *big.Int, err error) {
+	// SEC 1, Version 2.0, Section 4.1.3
+	N := c.Params().N
+	if N.Sign() == 0 {
+		return nil, nil, errZeroParam
+	}
+	var k, kInv *big.Int
+	for {
+		for {
+			k, err = randFieldElement(c, *csprng)
+			if err != nil {
+				r = nil
+				return
+			}
+
+			if in, ok := priv.Curve.(invertible); ok {
+				kInv = in.Inverse(k)
+			} else {
+				kInv = fermatInverse(k, N) // N != 0
+			}
+
+			r, _ = priv.Curve.ScalarBaseMult(k.Bytes())
+			r.Mod(r, N)
+			if r.Sign() != 0 {
+				break
+			}
+		}
+
+		e := hashToInt(hash, c)
+		s = new(big.Int).Mul(priv.D, r)
+		s.Add(s, e)
+		s.Mul(s, kInv)
+		s.Mod(s, N) // N != 0
+		if s.Sign() != 0 {
+			break
+		}
+	}
+
+	return
+}
+
+// SignASN1 signs a hash (which should be the result of hashing a larger message)
+// using the private key, priv. If the hash is longer than the bit-length of the
+// private key's curve order, the hash will be truncated to that length. It
+// returns the ASN.1 encoded signature.
+func SignASN1(rand io.Reader, priv *PrivateKey, hash []byte) ([]byte, error) {
+	return priv.Sign(rand, hash, nil)
+}
+
+// Verify verifies the signature in r, s of hash using the public key, pub. Its
+// return value records whether the signature is valid. Most applications should
+// use VerifyASN1 instead of dealing directly with r, s.
+func Verify(pub *PublicKey, hash []byte, r, s *big.Int) bool {
+	if boring.Enabled {
+		key, err := boringPublicKey(pub)
+		if err != nil {
+			return false
+		}
+		var b cryptobyte.Builder
+		b.AddASN1(asn1.SEQUENCE, func(b *cryptobyte.Builder) {
+			b.AddASN1BigInt(r)
+			b.AddASN1BigInt(s)
+		})
+		sig, err := b.Bytes()
+		if err != nil {
+			return false
+		}
+		return boring.VerifyECDSA(key, hash, sig)
+	}
+	boring.UnreachableExceptTests()
+
+	c := pub.Curve
+	N := c.Params().N
+
+	if r.Sign() <= 0 || s.Sign() <= 0 {
+		return false
+	}
+	if r.Cmp(N) >= 0 || s.Cmp(N) >= 0 {
+		return false
+	}
+	return verify(pub, c, hash, r, s)
+}
+
+func verifyGeneric(pub *PublicKey, c elliptic.Curve, hash []byte, r, s *big.Int) bool {
+	// SEC 1, Version 2.0, Section 4.1.4
+	e := hashToInt(hash, c)
+	var w *big.Int
+	N := c.Params().N
+	if in, ok := c.(invertible); ok {
+		w = in.Inverse(s)
+	} else {
+		w = new(big.Int).ModInverse(s, N)
+	}
+
+	u1 := e.Mul(e, w)
+	u1.Mod(u1, N)
+	u2 := w.Mul(r, w)
+	u2.Mod(u2, N)
+
+	// Check if implements S1*g + S2*p
+	var x, y *big.Int
+	if opt, ok := c.(combinedMult); ok {
+		x, y = opt.CombinedMult(pub.X, pub.Y, u1.Bytes(), u2.Bytes())
+	} else {
+		x1, y1 := c.ScalarBaseMult(u1.Bytes())
+		x2, y2 := c.ScalarMult(pub.X, pub.Y, u2.Bytes())
+		x, y = c.Add(x1, y1, x2, y2)
+	}
+
+	if x.Sign() == 0 && y.Sign() == 0 {
+		return false
+	}
+	x.Mod(x, N)
+	return x.Cmp(r) == 0
+}
+
+// VerifyASN1 verifies the ASN.1 encoded signature, sig, of hash using the
+// public key, pub. Its return value records whether the signature is valid.
+func VerifyASN1(pub *PublicKey, hash, sig []byte) bool {
+	var (
+		r, s  = &big.Int{}, &big.Int{}
+		inner cryptobyte.String
+	)
+	input := cryptobyte.String(sig)
+	if !input.ReadASN1(&inner, asn1.SEQUENCE) ||
+		!input.Empty() ||
+		!inner.ReadASN1Integer(r) ||
+		!inner.ReadASN1Integer(s) ||
+		!inner.Empty() {
+		return false
+	}
+	return Verify(pub, hash, r, s)
+}
+
+type zr struct{}
+
+// Read replaces the contents of dst with zeros. It is safe for concurrent use.
+func (zr) Read(dst []byte) (n int, err error) {
+	for i := range dst {
+		dst[i] = 0
+	}
+	return len(dst), nil
+}
+
+var zeroReader = zr{}
diff --git a/contrib/go/_std_1.18/src/crypto/ecdsa/ecdsa_noasm.go b/contrib/go/_std_1.19/src/crypto/ecdsa/ecdsa_noasm.go
index 7fbca10b56..7fbca10b56 100644
--- a/contrib/go/_std_1.18/src/crypto/ecdsa/ecdsa_noasm.go
+++ b/contrib/go/_std_1.19/src/crypto/ecdsa/ecdsa_noasm.go
diff --git a/contrib/go/_std_1.19/src/crypto/ecdsa/notboring.go b/contrib/go/_std_1.19/src/crypto/ecdsa/notboring.go
new file mode 100644
index 0000000000..039bd82ed2
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/ecdsa/notboring.go
@@ -0,0 +1,16 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !boringcrypto
+
+package ecdsa
+
+import "crypto/internal/boring"
+
+func boringPublicKey(*PublicKey) (*boring.PublicKeyECDSA, error) {
+	panic("boringcrypto: not available")
+}
+func boringPrivateKey(*PrivateKey) (*boring.PrivateKeyECDSA, error) {
+	panic("boringcrypto: not available")
+}
diff --git a/contrib/go/_std_1.19/src/crypto/ed25519/ed25519.go b/contrib/go/_std_1.19/src/crypto/ed25519/ed25519.go
new file mode 100644
index 0000000000..d43dd12d08
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/ed25519/ed25519.go
@@ -0,0 +1,230 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package ed25519 implements the Ed25519 signature algorithm. See
+// https://ed25519.cr.yp.to/.
+//
+// These functions are also compatible with the “Ed25519” function defined in
+// RFC 8032. However, unlike RFC 8032's formulation, this package's private key
+// representation includes a public key suffix to make multiple signing
+// operations with the same key more efficient. This package refers to the RFC
+// 8032 private key as the “seed”.
+package ed25519
+
+import (
+	"bytes"
+	"crypto"
+	"crypto/internal/edwards25519"
+	cryptorand "crypto/rand"
+	"crypto/sha512"
+	"errors"
+	"io"
+	"strconv"
+)
+
+const (
+	// PublicKeySize is the size, in bytes, of public keys as used in this package.
+	PublicKeySize = 32
+	// PrivateKeySize is the size, in bytes, of private keys as used in this package.
+	PrivateKeySize = 64
+	// SignatureSize is the size, in bytes, of signatures generated and verified by this package.
+	SignatureSize = 64
+	// SeedSize is the size, in bytes, of private key seeds. These are the private key representations used by RFC 8032.
+	SeedSize = 32
+)
+
+// PublicKey is the type of Ed25519 public keys.
+type PublicKey []byte
+
+// Any methods implemented on PublicKey might need to also be implemented on
+// PrivateKey, as the latter embeds the former and will expose its methods.
+
+// Equal reports whether pub and x have the same value.
+func (pub PublicKey) Equal(x crypto.PublicKey) bool {
+	xx, ok := x.(PublicKey)
+	if !ok {
+		return false
+	}
+	return bytes.Equal(pub, xx)
+}
+
+// PrivateKey is the type of Ed25519 private keys. It implements crypto.Signer.
+type PrivateKey []byte
+
+// Public returns the PublicKey corresponding to priv.
+func (priv PrivateKey) Public() crypto.PublicKey {
+	publicKey := make([]byte, PublicKeySize)
+	copy(publicKey, priv[32:])
+	return PublicKey(publicKey)
+}
+
+// Equal reports whether priv and x have the same value.
+func (priv PrivateKey) Equal(x crypto.PrivateKey) bool {
+	xx, ok := x.(PrivateKey)
+	if !ok {
+		return false
+	}
+	return bytes.Equal(priv, xx)
+}
+
+// Seed returns the private key seed corresponding to priv. It is provided for
+// interoperability with RFC 8032. RFC 8032's private keys correspond to seeds
+// in this package.
+func (priv PrivateKey) Seed() []byte {
+	seed := make([]byte, SeedSize)
+	copy(seed, priv[:32])
+	return seed
+}
+
+// Sign signs the given message with priv.
+// Ed25519 performs two passes over messages to be signed and therefore cannot
+// handle pre-hashed messages. Thus opts.HashFunc() must return zero to
+// indicate the message hasn't been hashed. This can be achieved by passing
+// crypto.Hash(0) as the value for opts.
+func (priv PrivateKey) Sign(rand io.Reader, message []byte, opts crypto.SignerOpts) (signature []byte, err error) {
+	if opts.HashFunc() != crypto.Hash(0) {
+		return nil, errors.New("ed25519: cannot sign hashed message")
+	}
+
+	return Sign(priv, message), nil
+}
+
+// GenerateKey generates a public/private key pair using entropy from rand.
+// If rand is nil, crypto/rand.Reader will be used.
+func GenerateKey(rand io.Reader) (PublicKey, PrivateKey, error) {
+	if rand == nil {
+		rand = cryptorand.Reader
+	}
+
+	seed := make([]byte, SeedSize)
+	if _, err := io.ReadFull(rand, seed); err != nil {
+		return nil, nil, err
+	}
+
+	privateKey := NewKeyFromSeed(seed)
+	publicKey := make([]byte, PublicKeySize)
+	copy(publicKey, privateKey[32:])
+
+	return publicKey, privateKey, nil
+}
+
+// NewKeyFromSeed calculates a private key from a seed. It will panic if
+// len(seed) is not SeedSize. This function is provided for interoperability
+// with RFC 8032. RFC 8032's private keys correspond to seeds in this
+// package.
+func NewKeyFromSeed(seed []byte) PrivateKey {
+	// Outline the function body so that the returned key can be stack-allocated.
+	privateKey := make([]byte, PrivateKeySize)
+	newKeyFromSeed(privateKey, seed)
+	return privateKey
+}
+
+func newKeyFromSeed(privateKey, seed []byte) {
+	if l := len(seed); l != SeedSize {
+		panic("ed25519: bad seed length: " + strconv.Itoa(l))
+	}
+
+	h := sha512.Sum512(seed)
+	s, err := edwards25519.NewScalar().SetBytesWithClamping(h[:32])
+	if err != nil {
+		panic("ed25519: internal error: setting scalar failed")
+	}
+	A := (&edwards25519.Point{}).ScalarBaseMult(s)
+
+	publicKey := A.Bytes()
+
+	copy(privateKey, seed)
+	copy(privateKey[32:], publicKey)
+}
+
+// Sign signs the message with privateKey and returns a signature. It will
+// panic if len(privateKey) is not PrivateKeySize.
+func Sign(privateKey PrivateKey, message []byte) []byte {
+	// Outline the function body so that the returned signature can be
+	// stack-allocated.
+	signature := make([]byte, SignatureSize)
+	sign(signature, privateKey, message)
+	return signature
+}
+
+func sign(signature, privateKey, message []byte) {
+	if l := len(privateKey); l != PrivateKeySize {
+		panic("ed25519: bad private key length: " + strconv.Itoa(l))
+	}
+	seed, publicKey := privateKey[:SeedSize], privateKey[SeedSize:]
+
+	h := sha512.Sum512(seed)
+	s, err := edwards25519.NewScalar().SetBytesWithClamping(h[:32])
+	if err != nil {
+		panic("ed25519: internal error: setting scalar failed")
+	}
+	prefix := h[32:]
+
+	mh := sha512.New()
+	mh.Write(prefix)
+	mh.Write(message)
+	messageDigest := make([]byte, 0, sha512.Size)
+	messageDigest = mh.Sum(messageDigest)
+	r, err := edwards25519.NewScalar().SetUniformBytes(messageDigest)
+	if err != nil {
+		panic("ed25519: internal error: setting scalar failed")
+	}
+
+	R := (&edwards25519.Point{}).ScalarBaseMult(r)
+
+	kh := sha512.New()
+	kh.Write(R.Bytes())
+	kh.Write(publicKey)
+	kh.Write(message)
+	hramDigest := make([]byte, 0, sha512.Size)
+	hramDigest = kh.Sum(hramDigest)
+	k, err := edwards25519.NewScalar().SetUniformBytes(hramDigest)
+	if err != nil {
+		panic("ed25519: internal error: setting scalar failed")
+	}
+
+	S := edwards25519.NewScalar().MultiplyAdd(k, s, r)
+
+	copy(signature[:32], R.Bytes())
+	copy(signature[32:], S.Bytes())
+}
+
+// Verify reports whether sig is a valid signature of message by publicKey. It
+// will panic if len(publicKey) is not PublicKeySize.
+func Verify(publicKey PublicKey, message, sig []byte) bool {
+	if l := len(publicKey); l != PublicKeySize {
+		panic("ed25519: bad public key length: " + strconv.Itoa(l))
+	}
+
+	if len(sig) != SignatureSize || sig[63]&224 != 0 {
+		return false
+	}
+
+	A, err := (&edwards25519.Point{}).SetBytes(publicKey)
+	if err != nil {
+		return false
+	}
+
+	kh := sha512.New()
+	kh.Write(sig[:32])
+	kh.Write(publicKey)
+	kh.Write(message)
+	hramDigest := make([]byte, 0, sha512.Size)
+	hramDigest = kh.Sum(hramDigest)
+	k, err := edwards25519.NewScalar().SetUniformBytes(hramDigest)
+	if err != nil {
+		panic("ed25519: internal error: setting scalar failed")
+	}
+
+	S, err := edwards25519.NewScalar().SetCanonicalBytes(sig[32:])
+	if err != nil {
+		return false
+	}
+
+	// [S]B = R + [k]A --> [k](-A) + [S]B = R
+	minusA := (&edwards25519.Point{}).Negate(A)
+	R := (&edwards25519.Point{}).VarTimeDoubleScalarBaseMult(k, minusA, S)
+
+	return bytes.Equal(sig[:32], R.Bytes())
+}
diff --git a/contrib/go/_std_1.19/src/crypto/elliptic/elliptic.go b/contrib/go/_std_1.19/src/crypto/elliptic/elliptic.go
new file mode 100644
index 0000000000..8c0b60b889
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/elliptic/elliptic.go
@@ -0,0 +1,242 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package elliptic implements the standard NIST P-224, P-256, P-384, and P-521
+// elliptic curves over prime fields.
+package elliptic
+
+import (
+	"io"
+	"math/big"
+	"sync"
+)
+
+// A Curve represents a short-form Weierstrass curve with a=-3.
+//
+// The behavior of Add, Double, and ScalarMult when the input is not a point on
+// the curve is undefined.
+//
+// Note that the conventional point at infinity (0, 0) is not considered on the
+// curve, although it can be returned by Add, Double, ScalarMult, or
+// ScalarBaseMult (but not the Unmarshal or UnmarshalCompressed functions).
+type Curve interface {
+	// Params returns the parameters for the curve.
+	Params() *CurveParams
+	// IsOnCurve reports whether the given (x,y) lies on the curve.
+	IsOnCurve(x, y *big.Int) bool
+	// Add returns the sum of (x1,y1) and (x2,y2)
+	Add(x1, y1, x2, y2 *big.Int) (x, y *big.Int)
+	// Double returns 2*(x,y)
+	Double(x1, y1 *big.Int) (x, y *big.Int)
+	// ScalarMult returns k*(Bx,By) where k is a number in big-endian form.
+	ScalarMult(x1, y1 *big.Int, k []byte) (x, y *big.Int)
+	// ScalarBaseMult returns k*G, where G is the base point of the group
+	// and k is an integer in big-endian form.
+	ScalarBaseMult(k []byte) (x, y *big.Int)
+}
+
+var mask = []byte{0xff, 0x1, 0x3, 0x7, 0xf, 0x1f, 0x3f, 0x7f}
+
+// GenerateKey returns a public/private key pair. The private key is
+// generated using the given reader, which must return random data.
+func GenerateKey(curve Curve, rand io.Reader) (priv []byte, x, y *big.Int, err error) {
+	N := curve.Params().N
+	bitSize := N.BitLen()
+	byteLen := (bitSize + 7) / 8
+	priv = make([]byte, byteLen)
+
+	for x == nil {
+		_, err = io.ReadFull(rand, priv)
+		if err != nil {
+			return
+		}
+		// We have to mask off any excess bits in the case that the size of the
+		// underlying field is not a whole number of bytes.
+		priv[0] &= mask[bitSize%8]
+		// This is because, in tests, rand will return all zeros and we don't
+		// want to get the point at infinity and loop forever.
+		priv[1] ^= 0x42
+
+		// If the scalar is out of range, sample another random number.
+		if new(big.Int).SetBytes(priv).Cmp(N) >= 0 {
+			continue
+		}
+
+		x, y = curve.ScalarBaseMult(priv)
+	}
+	return
+}
+
+// Marshal converts a point on the curve into the uncompressed form specified in
+// SEC 1, Version 2.0, Section 2.3.3. If the point is not on the curve (or is
+// the conventional point at infinity), the behavior is undefined.
+func Marshal(curve Curve, x, y *big.Int) []byte {
+	panicIfNotOnCurve(curve, x, y)
+
+	byteLen := (curve.Params().BitSize + 7) / 8
+
+	ret := make([]byte, 1+2*byteLen)
+	ret[0] = 4 // uncompressed point
+
+	x.FillBytes(ret[1 : 1+byteLen])
+	y.FillBytes(ret[1+byteLen : 1+2*byteLen])
+
+	return ret
+}
+
+// MarshalCompressed converts a point on the curve into the compressed form
+// specified in SEC 1, Version 2.0, Section 2.3.3. If the point is not on the
+// curve (or is the conventional point at infinity), the behavior is undefined.
+func MarshalCompressed(curve Curve, x, y *big.Int) []byte {
+	panicIfNotOnCurve(curve, x, y)
+	byteLen := (curve.Params().BitSize + 7) / 8
+	compressed := make([]byte, 1+byteLen)
+	compressed[0] = byte(y.Bit(0)) | 2
+	x.FillBytes(compressed[1:])
+	return compressed
+}
+
+// unmarshaler is implemented by curves with their own constant-time Unmarshal.
+//
+// There isn't an equivalent interface for Marshal/MarshalCompressed because
+// that doesn't involve any mathematical operations, only FillBytes and Bit.
+type unmarshaler interface {
+	Unmarshal([]byte) (x, y *big.Int)
+	UnmarshalCompressed([]byte) (x, y *big.Int)
+}
+
+// Assert that the known curves implement unmarshaler.
+var _ = []unmarshaler{p224, p256, p384, p521}
+
+// Unmarshal converts a point, serialized by Marshal, into an x, y pair. It is
+// an error if the point is not in uncompressed form, is not on the curve, or is
+// the point at infinity. On error, x = nil.
+func Unmarshal(curve Curve, data []byte) (x, y *big.Int) {
+	if c, ok := curve.(unmarshaler); ok {
+		return c.Unmarshal(data)
+	}
+
+	byteLen := (curve.Params().BitSize + 7) / 8
+	if len(data) != 1+2*byteLen {
+		return nil, nil
+	}
+	if data[0] != 4 { // uncompressed form
+		return nil, nil
+	}
+	p := curve.Params().P
+	x = new(big.Int).SetBytes(data[1 : 1+byteLen])
+	y = new(big.Int).SetBytes(data[1+byteLen:])
+	if x.Cmp(p) >= 0 || y.Cmp(p) >= 0 {
+		return nil, nil
+	}
+	if !curve.IsOnCurve(x, y) {
+		return nil, nil
+	}
+	return
+}
+
+// UnmarshalCompressed converts a point, serialized by MarshalCompressed, into
+// an x, y pair. It is an error if the point is not in compressed form, is not
+// on the curve, or is the point at infinity. On error, x = nil.
+func UnmarshalCompressed(curve Curve, data []byte) (x, y *big.Int) {
+	if c, ok := curve.(unmarshaler); ok {
+		return c.UnmarshalCompressed(data)
+	}
+
+	byteLen := (curve.Params().BitSize + 7) / 8
+	if len(data) != 1+byteLen {
+		return nil, nil
+	}
+	if data[0] != 2 && data[0] != 3 { // compressed form
+		return nil, nil
+	}
+	p := curve.Params().P
+	x = new(big.Int).SetBytes(data[1:])
+	if x.Cmp(p) >= 0 {
+		return nil, nil
+	}
+	// y² = x³ - 3x + b
+	y = curve.Params().polynomial(x)
+	y = y.ModSqrt(y, p)
+	if y == nil {
+		return nil, nil
+	}
+	if byte(y.Bit(0)) != data[0]&1 {
+		y.Neg(y).Mod(y, p)
+	}
+	if !curve.IsOnCurve(x, y) {
+		return nil, nil
+	}
+	return
+}
+
+func panicIfNotOnCurve(curve Curve, x, y *big.Int) {
+	// (0, 0) is the point at infinity by convention. It's ok to operate on it,
+	// although IsOnCurve is documented to return false for it. See Issue 37294.
+	if x.Sign() == 0 && y.Sign() == 0 {
+		return
+	}
+
+	if !curve.IsOnCurve(x, y) {
+		panic("crypto/elliptic: attempted operation on invalid point")
+	}
+}
+
+var initonce sync.Once
+
+func initAll() {
+	initP224()
+	initP256()
+	initP384()
+	initP521()
+}
+
+// P224 returns a Curve which implements NIST P-224 (FIPS 186-3, section D.2.2),
+// also known as secp224r1. The CurveParams.Name of this Curve is "P-224".
+//
+// Multiple invocations of this function will return the same value, so it can
+// be used for equality checks and switch statements.
+//
+// The cryptographic operations are implemented using constant-time algorithms.
+func P224() Curve {
+	initonce.Do(initAll)
+	return p224
+}
+
+// P256 returns a Curve which implements NIST P-256 (FIPS 186-3, section D.2.3),
+// also known as secp256r1 or prime256v1. The CurveParams.Name of this Curve is
+// "P-256".
+//
+// Multiple invocations of this function will return the same value, so it can
+// be used for equality checks and switch statements.
+//
+// The cryptographic operations are implemented using constant-time algorithms.
+func P256() Curve {
+	initonce.Do(initAll)
+	return p256
+}
+
+// P384 returns a Curve which implements NIST P-384 (FIPS 186-3, section D.2.4),
+// also known as secp384r1. The CurveParams.Name of this Curve is "P-384".
+//
+// Multiple invocations of this function will return the same value, so it can
+// be used for equality checks and switch statements.
+//
+// The cryptographic operations are implemented using constant-time algorithms.
+func P384() Curve {
+	initonce.Do(initAll)
+	return p384
+}
+
+// P521 returns a Curve which implements NIST P-521 (FIPS 186-3, section D.2.5),
+// also known as secp521r1. The CurveParams.Name of this Curve is "P-521".
+//
+// Multiple invocations of this function will return the same value, so it can
+// be used for equality checks and switch statements.
+//
+// The cryptographic operations are implemented using constant-time algorithms.
+func P521() Curve {
+	initonce.Do(initAll)
+	return p521
+}
diff --git a/contrib/go/_std_1.19/src/crypto/elliptic/nistec.go b/contrib/go/_std_1.19/src/crypto/elliptic/nistec.go
new file mode 100644
index 0000000000..9bb46008b5
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/elliptic/nistec.go
@@ -0,0 +1,295 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package elliptic
+
+import (
+	"crypto/internal/nistec"
+	"errors"
+	"math/big"
+)
+
+var p224 = &nistCurve[*nistec.P224Point]{
+	newPoint: nistec.NewP224Point,
+}
+
+func initP224() {
+	p224.params = &CurveParams{
+		Name:    "P-224",
+		BitSize: 224,
+		// FIPS 186-4, section D.1.2.2
+		P:  bigFromDecimal("26959946667150639794667015087019630673557916260026308143510066298881"),
+		N:  bigFromDecimal("26959946667150639794667015087019625940457807714424391721682722368061"),
+		B:  bigFromHex("b4050a850c04b3abf54132565044b0b7d7bfd8ba270b39432355ffb4"),
+		Gx: bigFromHex("b70e0cbd6bb4bf7f321390b94a03c1d356c21122343280d6115c1d21"),
+		Gy: bigFromHex("bd376388b5f723fb4c22dfe6cd4375a05a07476444d5819985007e34"),
+	}
+}
+
+type p256Curve struct {
+	nistCurve[*nistec.P256Point]
+}
+
+var p256 = &p256Curve{nistCurve[*nistec.P256Point]{
+	newPoint: nistec.NewP256Point,
+}}
+
+func initP256() {
+	p256.params = &CurveParams{
+		Name:    "P-256",
+		BitSize: 256,
+		// FIPS 186-4, section D.1.2.3
+		P:  bigFromDecimal("115792089210356248762697446949407573530086143415290314195533631308867097853951"),
+		N:  bigFromDecimal("115792089210356248762697446949407573529996955224135760342422259061068512044369"),
+		B:  bigFromHex("5ac635d8aa3a93e7b3ebbd55769886bc651d06b0cc53b0f63bce3c3e27d2604b"),
+		Gx: bigFromHex("6b17d1f2e12c4247f8bce6e563a440f277037d812deb33a0f4a13945d898c296"),
+		Gy: bigFromHex("4fe342e2fe1a7f9b8ee7eb4a7c0f9e162bce33576b315ececbb6406837bf51f5"),
+	}
+}
+
+var p384 = &nistCurve[*nistec.P384Point]{
+	newPoint: nistec.NewP384Point,
+}
+
+func initP384() {
+	p384.params = &CurveParams{
+		Name:    "P-384",
+		BitSize: 384,
+		// FIPS 186-4, section D.1.2.4
+		P: bigFromDecimal("394020061963944792122790401001436138050797392704654" +
+			"46667948293404245721771496870329047266088258938001861606973112319"),
+		N: bigFromDecimal("394020061963944792122790401001436138050797392704654" +
+			"46667946905279627659399113263569398956308152294913554433653942643"),
+		B: bigFromHex("b3312fa7e23ee7e4988e056be3f82d19181d9c6efe8141120314088" +
+			"f5013875ac656398d8a2ed19d2a85c8edd3ec2aef"),
+		Gx: bigFromHex("aa87ca22be8b05378eb1c71ef320ad746e1d3b628ba79b9859f741" +
+			"e082542a385502f25dbf55296c3a545e3872760ab7"),
+		Gy: bigFromHex("3617de4a96262c6f5d9e98bf9292dc29f8f41dbd289a147ce9da31" +
+			"13b5f0b8c00a60b1ce1d7e819d7a431d7c90ea0e5f"),
+	}
+}
+
+var p521 = &nistCurve[*nistec.P521Point]{
+	newPoint: nistec.NewP521Point,
+}
+
+func initP521() {
+	p521.params = &CurveParams{
+		Name:    "P-521",
+		BitSize: 521,
+		// FIPS 186-4, section D.1.2.5
+		P: bigFromDecimal("68647976601306097149819007990813932172694353001433" +
+			"0540939446345918554318339765605212255964066145455497729631139148" +
+			"0858037121987999716643812574028291115057151"),
+		N: bigFromDecimal("68647976601306097149819007990813932172694353001433" +
+			"0540939446345918554318339765539424505774633321719753296399637136" +
+			"3321113864768612440380340372808892707005449"),
+		B: bigFromHex("0051953eb9618e1c9a1f929a21a0b68540eea2da725b99b315f3b8" +
+			"b489918ef109e156193951ec7e937b1652c0bd3bb1bf073573df883d2c34f1ef" +
+			"451fd46b503f00"),
+		Gx: bigFromHex("00c6858e06b70404e9cd9e3ecb662395b4429c648139053fb521f8" +
+			"28af606b4d3dbaa14b5e77efe75928fe1dc127a2ffa8de3348b3c1856a429bf9" +
+			"7e7e31c2e5bd66"),
+		Gy: bigFromHex("011839296a789a3bc0045c8a5fb42c7d1bd998f54449579b446817" +
+			"afbd17273e662c97ee72995ef42640c550b9013fad0761353c7086a272c24088" +
+			"be94769fd16650"),
+	}
+}
+
+// nistCurve is a Curve implementation based on a nistec Point.
+//
+// It's a wrapper that exposes the big.Int-based Curve interface and encodes the
+// legacy idiosyncrasies it requires, such as invalid and infinity point
+// handling.
+//
+// To interact with the nistec package, points are encoded into and decoded from
+// properly formatted byte slices. All big.Int use is limited to this package.
+// Encoding and decoding is 1/1000th of the runtime of a scalar multiplication,
+// so the overhead is acceptable.
+type nistCurve[Point nistPoint[Point]] struct {
+	newPoint func() Point
+	params   *CurveParams
+}
+
+// nistPoint is a generic constraint for the nistec Point types.
+type nistPoint[T any] interface {
+	Bytes() []byte
+	SetBytes([]byte) (T, error)
+	Add(T, T) T
+	Double(T) T
+	ScalarMult(T, []byte) (T, error)
+	ScalarBaseMult([]byte) (T, error)
+}
+
+func (curve *nistCurve[Point]) Params() *CurveParams {
+	return curve.params
+}
+
+func (curve *nistCurve[Point]) IsOnCurve(x, y *big.Int) bool {
+	// IsOnCurve is documented to reject (0, 0), the conventional point at
+	// infinity, which however is accepted by pointFromAffine.
+	if x.Sign() == 0 && y.Sign() == 0 {
+		return false
+	}
+	_, err := curve.pointFromAffine(x, y)
+	return err == nil
+}
+
+func (curve *nistCurve[Point]) pointFromAffine(x, y *big.Int) (p Point, err error) {
+	p = curve.newPoint()
+	// (0, 0) is by convention the point at infinity, which can't be represented
+	// in affine coordinates. See Issue 37294.
+	if x.Sign() == 0 && y.Sign() == 0 {
+		return p, nil
+	}
+	// Reject values that would not get correctly encoded.
+	if x.Sign() < 0 || y.Sign() < 0 {
+		return p, errors.New("negative coordinate")
+	}
+	if x.BitLen() > curve.params.BitSize || y.BitLen() > curve.params.BitSize {
+		return p, errors.New("overflowing coordinate")
+	}
+	// Encode the coordinates and let SetBytes reject invalid points.
+	byteLen := (curve.params.BitSize + 7) / 8
+	buf := make([]byte, 1+2*byteLen)
+	buf[0] = 4 // uncompressed point
+	x.FillBytes(buf[1 : 1+byteLen])
+	y.FillBytes(buf[1+byteLen : 1+2*byteLen])
+	return p.SetBytes(buf)
+}
+
+func (curve *nistCurve[Point]) pointToAffine(p Point) (x, y *big.Int) {
+	out := p.Bytes()
+	if len(out) == 1 && out[0] == 0 {
+		// This is the encoding of the point at infinity, which the affine
+		// coordinates API represents as (0, 0) by convention.
+		return new(big.Int), new(big.Int)
+	}
+	byteLen := (curve.params.BitSize + 7) / 8
+	x = new(big.Int).SetBytes(out[1 : 1+byteLen])
+	y = new(big.Int).SetBytes(out[1+byteLen:])
+	return x, y
+}
+
+func (curve *nistCurve[Point]) Add(x1, y1, x2, y2 *big.Int) (*big.Int, *big.Int) {
+	p1, err := curve.pointFromAffine(x1, y1)
+	if err != nil {
+		panic("crypto/elliptic: Add was called on an invalid point")
+	}
+	p2, err := curve.pointFromAffine(x2, y2)
+	if err != nil {
+		panic("crypto/elliptic: Add was called on an invalid point")
+	}
+	return curve.pointToAffine(p1.Add(p1, p2))
+}
+
+func (curve *nistCurve[Point]) Double(x1, y1 *big.Int) (*big.Int, *big.Int) {
+	p, err := curve.pointFromAffine(x1, y1)
+	if err != nil {
+		panic("crypto/elliptic: Double was called on an invalid point")
+	}
+	return curve.pointToAffine(p.Double(p))
+}
+
+// normalizeScalar brings the scalar within the byte size of the order of the
+// curve, as expected by the nistec scalar multiplication functions.
+func (curve *nistCurve[Point]) normalizeScalar(scalar []byte) []byte {
+	byteSize := (curve.params.N.BitLen() + 7) / 8
+	if len(scalar) == byteSize {
+		return scalar
+	}
+	s := new(big.Int).SetBytes(scalar)
+	if len(scalar) > byteSize {
+		s.Mod(s, curve.params.N)
+	}
+	out := make([]byte, byteSize)
+	return s.FillBytes(out)
+}
+
+func (curve *nistCurve[Point]) ScalarMult(Bx, By *big.Int, scalar []byte) (*big.Int, *big.Int) {
+	p, err := curve.pointFromAffine(Bx, By)
+	if err != nil {
+		panic("crypto/elliptic: ScalarMult was called on an invalid point")
+	}
+	scalar = curve.normalizeScalar(scalar)
+	p, err = p.ScalarMult(p, scalar)
+	if err != nil {
+		panic("crypto/elliptic: nistec rejected normalized scalar")
+	}
+	return curve.pointToAffine(p)
+}
+
+func (curve *nistCurve[Point]) ScalarBaseMult(scalar []byte) (*big.Int, *big.Int) {
+	scalar = curve.normalizeScalar(scalar)
+	p, err := curve.newPoint().ScalarBaseMult(scalar)
+	if err != nil {
+		panic("crypto/elliptic: nistec rejected normalized scalar")
+	}
+	return curve.pointToAffine(p)
+}
+
+// CombinedMult returns [s1]G + [s2]P where G is the generator. It's used
+// through an interface upgrade in crypto/ecdsa.
+func (curve *nistCurve[Point]) CombinedMult(Px, Py *big.Int, s1, s2 []byte) (x, y *big.Int) {
+	s1 = curve.normalizeScalar(s1)
+	q, err := curve.newPoint().ScalarBaseMult(s1)
+	if err != nil {
+		panic("crypto/elliptic: nistec rejected normalized scalar")
+	}
+	p, err := curve.pointFromAffine(Px, Py)
+	if err != nil {
+		panic("crypto/elliptic: CombinedMult was called on an invalid point")
+	}
+	s2 = curve.normalizeScalar(s2)
+	p, err = p.ScalarMult(p, s2)
+	if err != nil {
+		panic("crypto/elliptic: nistec rejected normalized scalar")
+	}
+	return curve.pointToAffine(p.Add(p, q))
+}
+
+func (curve *nistCurve[Point]) Unmarshal(data []byte) (x, y *big.Int) {
+	if len(data) == 0 || data[0] != 4 {
+		return nil, nil
+	}
+	// Use SetBytes to check that data encodes a valid point.
+	_, err := curve.newPoint().SetBytes(data)
+	if err != nil {
+		return nil, nil
+	}
+	// We don't use pointToAffine because it involves an expensive field
+	// inversion to convert from Jacobian to affine coordinates, which we
+	// already have.
+	byteLen := (curve.params.BitSize + 7) / 8
+	x = new(big.Int).SetBytes(data[1 : 1+byteLen])
+	y = new(big.Int).SetBytes(data[1+byteLen:])
+	return x, y
+}
+
+func (curve *nistCurve[Point]) UnmarshalCompressed(data []byte) (x, y *big.Int) {
+	if len(data) == 0 || (data[0] != 2 && data[0] != 3) {
+		return nil, nil
+	}
+	p, err := curve.newPoint().SetBytes(data)
+	if err != nil {
+		return nil, nil
+	}
+	return curve.pointToAffine(p)
+}
+
+func bigFromDecimal(s string) *big.Int {
+	b, ok := new(big.Int).SetString(s, 10)
+	if !ok {
+		panic("crypto/elliptic: internal error: invalid encoding")
+	}
+	return b
+}
+
+func bigFromHex(s string) *big.Int {
+	b, ok := new(big.Int).SetString(s, 16)
+	if !ok {
+		panic("crypto/elliptic: internal error: invalid encoding")
+	}
+	return b
+}
diff --git a/contrib/go/_std_1.19/src/crypto/elliptic/nistec_p256.go b/contrib/go/_std_1.19/src/crypto/elliptic/nistec_p256.go
new file mode 100644
index 0000000000..304f8f2659
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/elliptic/nistec_p256.go
@@ -0,0 +1,29 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build amd64 || arm64
+
+package elliptic
+
+import (
+	"crypto/internal/nistec"
+	"math/big"
+)
+
+func (c p256Curve) Inverse(k *big.Int) *big.Int {
+	if k.Sign() < 0 {
+		// This should never happen.
+		k = new(big.Int).Neg(k)
+	}
+	if k.Cmp(c.params.N) >= 0 {
+		// This should never happen.
+		k = new(big.Int).Mod(k, c.params.N)
+	}
+	scalar := k.FillBytes(make([]byte, 32))
+	inverse, err := nistec.P256OrdInverse(scalar)
+	if err != nil {
+		panic("crypto/elliptic: nistec rejected normalized scalar")
+	}
+	return new(big.Int).SetBytes(inverse)
+}
diff --git a/contrib/go/_std_1.19/src/crypto/elliptic/params.go b/contrib/go/_std_1.19/src/crypto/elliptic/params.go
new file mode 100644
index 0000000000..0ed929d61f
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/elliptic/params.go
@@ -0,0 +1,300 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package elliptic
+
+import "math/big"
+
+// CurveParams contains the parameters of an elliptic curve and also provides
+// a generic, non-constant time implementation of Curve.
+type CurveParams struct {
+	P       *big.Int // the order of the underlying field
+	N       *big.Int // the order of the base point
+	B       *big.Int // the constant of the curve equation
+	Gx, Gy  *big.Int // (x,y) of the base point
+	BitSize int      // the size of the underlying field
+	Name    string   // the canonical name of the curve
+}
+
+func (curve *CurveParams) Params() *CurveParams {
+	return curve
+}
+
+// CurveParams operates, internally, on Jacobian coordinates. For a given
+// (x, y) position on the curve, the Jacobian coordinates are (x1, y1, z1)
+// where x = x1/z1² and y = y1/z1³. The greatest speedups come when the whole
+// calculation can be performed within the transform (as in ScalarMult and
+// ScalarBaseMult). But even for Add and Double, it's faster to apply and
+// reverse the transform than to operate in affine coordinates.
+
+// polynomial returns x³ - 3x + b.
+func (curve *CurveParams) polynomial(x *big.Int) *big.Int {
+	x3 := new(big.Int).Mul(x, x)
+	x3.Mul(x3, x)
+
+	threeX := new(big.Int).Lsh(x, 1)
+	threeX.Add(threeX, x)
+
+	x3.Sub(x3, threeX)
+	x3.Add(x3, curve.B)
+	x3.Mod(x3, curve.P)
+
+	return x3
+}
+
+func (curve *CurveParams) IsOnCurve(x, y *big.Int) bool {
+	// If there is a dedicated constant-time implementation for this curve operation,
+	// use that instead of the generic one.
+	if specific, ok := matchesSpecificCurve(curve); ok {
+		return specific.IsOnCurve(x, y)
+	}
+
+	if x.Sign() < 0 || x.Cmp(curve.P) >= 0 ||
+		y.Sign() < 0 || y.Cmp(curve.P) >= 0 {
+		return false
+	}
+
+	// y² = x³ - 3x + b
+	y2 := new(big.Int).Mul(y, y)
+	y2.Mod(y2, curve.P)
+
+	return curve.polynomial(x).Cmp(y2) == 0
+}
+
+// zForAffine returns a Jacobian Z value for the affine point (x, y). If x and
+// y are zero, it assumes that they represent the point at infinity because (0,
+// 0) is not on the any of the curves handled here.
+func zForAffine(x, y *big.Int) *big.Int {
+	z := new(big.Int)
+	if x.Sign() != 0 || y.Sign() != 0 {
+		z.SetInt64(1)
+	}
+	return z
+}
+
+// affineFromJacobian reverses the Jacobian transform. See the comment at the
+// top of the file. If the point is ∞ it returns 0, 0.
+func (curve *CurveParams) affineFromJacobian(x, y, z *big.Int) (xOut, yOut *big.Int) {
+	if z.Sign() == 0 {
+		return new(big.Int), new(big.Int)
+	}
+
+	zinv := new(big.Int).ModInverse(z, curve.P)
+	zinvsq := new(big.Int).Mul(zinv, zinv)
+
+	xOut = new(big.Int).Mul(x, zinvsq)
+	xOut.Mod(xOut, curve.P)
+	zinvsq.Mul(zinvsq, zinv)
+	yOut = new(big.Int).Mul(y, zinvsq)
+	yOut.Mod(yOut, curve.P)
+	return
+}
+
+func (curve *CurveParams) Add(x1, y1, x2, y2 *big.Int) (*big.Int, *big.Int) {
+	// If there is a dedicated constant-time implementation for this curve operation,
+	// use that instead of the generic one.
+	if specific, ok := matchesSpecificCurve(curve); ok {
+		return specific.Add(x1, y1, x2, y2)
+	}
+	panicIfNotOnCurve(curve, x1, y1)
+	panicIfNotOnCurve(curve, x2, y2)
+
+	z1 := zForAffine(x1, y1)
+	z2 := zForAffine(x2, y2)
+	return curve.affineFromJacobian(curve.addJacobian(x1, y1, z1, x2, y2, z2))
+}
+
+// addJacobian takes two points in Jacobian coordinates, (x1, y1, z1) and
+// (x2, y2, z2) and returns their sum, also in Jacobian form.
+func (curve *CurveParams) addJacobian(x1, y1, z1, x2, y2, z2 *big.Int) (*big.Int, *big.Int, *big.Int) {
+	// See https://hyperelliptic.org/EFD/g1p/auto-shortw-jacobian-3.html#addition-add-2007-bl
+	x3, y3, z3 := new(big.Int), new(big.Int), new(big.Int)
+	if z1.Sign() == 0 {
+		x3.Set(x2)
+		y3.Set(y2)
+		z3.Set(z2)
+		return x3, y3, z3
+	}
+	if z2.Sign() == 0 {
+		x3.Set(x1)
+		y3.Set(y1)
+		z3.Set(z1)
+		return x3, y3, z3
+	}
+
+	z1z1 := new(big.Int).Mul(z1, z1)
+	z1z1.Mod(z1z1, curve.P)
+	z2z2 := new(big.Int).Mul(z2, z2)
+	z2z2.Mod(z2z2, curve.P)
+
+	u1 := new(big.Int).Mul(x1, z2z2)
+	u1.Mod(u1, curve.P)
+	u2 := new(big.Int).Mul(x2, z1z1)
+	u2.Mod(u2, curve.P)
+	h := new(big.Int).Sub(u2, u1)
+	xEqual := h.Sign() == 0
+	if h.Sign() == -1 {
+		h.Add(h, curve.P)
+	}
+	i := new(big.Int).Lsh(h, 1)
+	i.Mul(i, i)
+	j := new(big.Int).Mul(h, i)
+
+	s1 := new(big.Int).Mul(y1, z2)
+	s1.Mul(s1, z2z2)
+	s1.Mod(s1, curve.P)
+	s2 := new(big.Int).Mul(y2, z1)
+	s2.Mul(s2, z1z1)
+	s2.Mod(s2, curve.P)
+	r := new(big.Int).Sub(s2, s1)
+	if r.Sign() == -1 {
+		r.Add(r, curve.P)
+	}
+	yEqual := r.Sign() == 0
+	if xEqual && yEqual {
+		return curve.doubleJacobian(x1, y1, z1)
+	}
+	r.Lsh(r, 1)
+	v := new(big.Int).Mul(u1, i)
+
+	x3.Set(r)
+	x3.Mul(x3, x3)
+	x3.Sub(x3, j)
+	x3.Sub(x3, v)
+	x3.Sub(x3, v)
+	x3.Mod(x3, curve.P)
+
+	y3.Set(r)
+	v.Sub(v, x3)
+	y3.Mul(y3, v)
+	s1.Mul(s1, j)
+	s1.Lsh(s1, 1)
+	y3.Sub(y3, s1)
+	y3.Mod(y3, curve.P)
+
+	z3.Add(z1, z2)
+	z3.Mul(z3, z3)
+	z3.Sub(z3, z1z1)
+	z3.Sub(z3, z2z2)
+	z3.Mul(z3, h)
+	z3.Mod(z3, curve.P)
+
+	return x3, y3, z3
+}
+
+func (curve *CurveParams) Double(x1, y1 *big.Int) (*big.Int, *big.Int) {
+	// If there is a dedicated constant-time implementation for this curve operation,
+	// use that instead of the generic one.
+	if specific, ok := matchesSpecificCurve(curve); ok {
+		return specific.Double(x1, y1)
+	}
+	panicIfNotOnCurve(curve, x1, y1)
+
+	z1 := zForAffine(x1, y1)
+	return curve.affineFromJacobian(curve.doubleJacobian(x1, y1, z1))
+}
+
+// doubleJacobian takes a point in Jacobian coordinates, (x, y, z), and
+// returns its double, also in Jacobian form.
+func (curve *CurveParams) doubleJacobian(x, y, z *big.Int) (*big.Int, *big.Int, *big.Int) {
+	// See https://hyperelliptic.org/EFD/g1p/auto-shortw-jacobian-3.html#doubling-dbl-2001-b
+	delta := new(big.Int).Mul(z, z)
+	delta.Mod(delta, curve.P)
+	gamma := new(big.Int).Mul(y, y)
+	gamma.Mod(gamma, curve.P)
+	alpha := new(big.Int).Sub(x, delta)
+	if alpha.Sign() == -1 {
+		alpha.Add(alpha, curve.P)
+	}
+	alpha2 := new(big.Int).Add(x, delta)
+	alpha.Mul(alpha, alpha2)
+	alpha2.Set(alpha)
+	alpha.Lsh(alpha, 1)
+	alpha.Add(alpha, alpha2)
+
+	beta := alpha2.Mul(x, gamma)
+
+	x3 := new(big.Int).Mul(alpha, alpha)
+	beta8 := new(big.Int).Lsh(beta, 3)
+	beta8.Mod(beta8, curve.P)
+	x3.Sub(x3, beta8)
+	if x3.Sign() == -1 {
+		x3.Add(x3, curve.P)
+	}
+	x3.Mod(x3, curve.P)
+
+	z3 := new(big.Int).Add(y, z)
+	z3.Mul(z3, z3)
+	z3.Sub(z3, gamma)
+	if z3.Sign() == -1 {
+		z3.Add(z3, curve.P)
+	}
+	z3.Sub(z3, delta)
+	if z3.Sign() == -1 {
+		z3.Add(z3, curve.P)
+	}
+	z3.Mod(z3, curve.P)
+
+	beta.Lsh(beta, 2)
+	beta.Sub(beta, x3)
+	if beta.Sign() == -1 {
+		beta.Add(beta, curve.P)
+	}
+	y3 := alpha.Mul(alpha, beta)
+
+	gamma.Mul(gamma, gamma)
+	gamma.Lsh(gamma, 3)
+	gamma.Mod(gamma, curve.P)
+
+	y3.Sub(y3, gamma)
+	if y3.Sign() == -1 {
+		y3.Add(y3, curve.P)
+	}
+	y3.Mod(y3, curve.P)
+
+	return x3, y3, z3
+}
+
+func (curve *CurveParams) ScalarMult(Bx, By *big.Int, k []byte) (*big.Int, *big.Int) {
+	// If there is a dedicated constant-time implementation for this curve operation,
+	// use that instead of the generic one.
+	if specific, ok := matchesSpecificCurve(curve); ok {
+		return specific.ScalarMult(Bx, By, k)
+	}
+	panicIfNotOnCurve(curve, Bx, By)
+
+	Bz := new(big.Int).SetInt64(1)
+	x, y, z := new(big.Int), new(big.Int), new(big.Int)
+
+	for _, byte := range k {
+		for bitNum := 0; bitNum < 8; bitNum++ {
+			x, y, z = curve.doubleJacobian(x, y, z)
+			if byte&0x80 == 0x80 {
+				x, y, z = curve.addJacobian(Bx, By, Bz, x, y, z)
+			}
+			byte <<= 1
+		}
+	}
+
+	return curve.affineFromJacobian(x, y, z)
+}
+
+func (curve *CurveParams) ScalarBaseMult(k []byte) (*big.Int, *big.Int) {
+	// If there is a dedicated constant-time implementation for this curve operation,
+	// use that instead of the generic one.
+	if specific, ok := matchesSpecificCurve(curve); ok {
+		return specific.ScalarBaseMult(k)
+	}
+
+	return curve.ScalarMult(curve.Gx, curve.Gy, k)
+}
+
+func matchesSpecificCurve(params *CurveParams) (Curve, bool) {
+	for _, c := range []Curve{p224, p256, p384, p521} {
+		if params == c.Params() {
+			return c, true
+		}
+	}
+	return nil, false
+}
diff --git a/contrib/go/_std_1.19/src/crypto/hmac/hmac.go b/contrib/go/_std_1.19/src/crypto/hmac/hmac.go
new file mode 100644
index 0000000000..ed3ebc0602
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/hmac/hmac.go
@@ -0,0 +1,180 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package hmac implements the Keyed-Hash Message Authentication Code (HMAC) as
+defined in U.S. Federal Information Processing Standards Publication 198.
+An HMAC is a cryptographic hash that uses a key to sign a message.
+The receiver verifies the hash by recomputing it using the same key.
+
+Receivers should be careful to use Equal to compare MACs in order to avoid
+timing side-channels:
+
+	// ValidMAC reports whether messageMAC is a valid HMAC tag for message.
+	func ValidMAC(message, messageMAC, key []byte) bool {
+		mac := hmac.New(sha256.New, key)
+		mac.Write(message)
+		expectedMAC := mac.Sum(nil)
+		return hmac.Equal(messageMAC, expectedMAC)
+	}
+*/
+package hmac
+
+import (
+	"crypto/internal/boring"
+	"crypto/subtle"
+	"hash"
+)
+
+// FIPS 198-1:
+// https://csrc.nist.gov/publications/fips/fips198-1/FIPS-198-1_final.pdf
+
+// key is zero padded to the block size of the hash function
+// ipad = 0x36 byte repeated for key length
+// opad = 0x5c byte repeated for key length
+// hmac = H([key ^ opad] H([key ^ ipad] text))
+
+// Marshalable is the combination of encoding.BinaryMarshaler and
+// encoding.BinaryUnmarshaler. Their method definitions are repeated here to
+// avoid a dependency on the encoding package.
+type marshalable interface {
+	MarshalBinary() ([]byte, error)
+	UnmarshalBinary([]byte) error
+}
+
+type hmac struct {
+	opad, ipad   []byte
+	outer, inner hash.Hash
+
+	// If marshaled is true, then opad and ipad do not contain a padded
+	// copy of the key, but rather the marshaled state of outer/inner after
+	// opad/ipad has been fed into it.
+	marshaled bool
+}
+
+func (h *hmac) Sum(in []byte) []byte {
+	origLen := len(in)
+	in = h.inner.Sum(in)
+
+	if h.marshaled {
+		if err := h.outer.(marshalable).UnmarshalBinary(h.opad); err != nil {
+			panic(err)
+		}
+	} else {
+		h.outer.Reset()
+		h.outer.Write(h.opad)
+	}
+	h.outer.Write(in[origLen:])
+	return h.outer.Sum(in[:origLen])
+}
+
+func (h *hmac) Write(p []byte) (n int, err error) {
+	return h.inner.Write(p)
+}
+
+func (h *hmac) Size() int      { return h.outer.Size() }
+func (h *hmac) BlockSize() int { return h.inner.BlockSize() }
+
+func (h *hmac) Reset() {
+	if h.marshaled {
+		if err := h.inner.(marshalable).UnmarshalBinary(h.ipad); err != nil {
+			panic(err)
+		}
+		return
+	}
+
+	h.inner.Reset()
+	h.inner.Write(h.ipad)
+
+	// If the underlying hash is marshalable, we can save some time by
+	// saving a copy of the hash state now, and restoring it on future
+	// calls to Reset and Sum instead of writing ipad/opad every time.
+	//
+	// If either hash is unmarshalable for whatever reason,
+	// it's safe to bail out here.
+	marshalableInner, innerOK := h.inner.(marshalable)
+	if !innerOK {
+		return
+	}
+	marshalableOuter, outerOK := h.outer.(marshalable)
+	if !outerOK {
+		return
+	}
+
+	imarshal, err := marshalableInner.MarshalBinary()
+	if err != nil {
+		return
+	}
+
+	h.outer.Reset()
+	h.outer.Write(h.opad)
+	omarshal, err := marshalableOuter.MarshalBinary()
+	if err != nil {
+		return
+	}
+
+	// Marshaling succeeded; save the marshaled state for later
+	h.ipad = imarshal
+	h.opad = omarshal
+	h.marshaled = true
+}
+
+// New returns a new HMAC hash using the given hash.Hash type and key.
+// New functions like sha256.New from crypto/sha256 can be used as h.
+// h must return a new Hash every time it is called.
+// Note that unlike other hash implementations in the standard library,
+// the returned Hash does not implement encoding.BinaryMarshaler
+// or encoding.BinaryUnmarshaler.
+func New(h func() hash.Hash, key []byte) hash.Hash {
+	if boring.Enabled {
+		hm := boring.NewHMAC(h, key)
+		if hm != nil {
+			return hm
+		}
+		// BoringCrypto did not recognize h, so fall through to standard Go code.
+	}
+	hm := new(hmac)
+	hm.outer = h()
+	hm.inner = h()
+	unique := true
+	func() {
+		defer func() {
+			// The comparison might panic if the underlying types are not comparable.
+			_ = recover()
+		}()
+		if hm.outer == hm.inner {
+			unique = false
+		}
+	}()
+	if !unique {
+		panic("crypto/hmac: hash generation function does not produce unique values")
+	}
+	blocksize := hm.inner.BlockSize()
+	hm.ipad = make([]byte, blocksize)
+	hm.opad = make([]byte, blocksize)
+	if len(key) > blocksize {
+		// If key is too big, hash it.
+		hm.outer.Write(key)
+		key = hm.outer.Sum(nil)
+	}
+	copy(hm.ipad, key)
+	copy(hm.opad, key)
+	for i := range hm.ipad {
+		hm.ipad[i] ^= 0x36
+	}
+	for i := range hm.opad {
+		hm.opad[i] ^= 0x5c
+	}
+	hm.inner.Write(hm.ipad)
+
+	return hm
+}
+
+// Equal compares two MACs for equality without leaking timing information.
+func Equal(mac1, mac2 []byte) bool {
+	// We don't have to be constant time if the lengths of the MACs are
+	// different as that suggests that a completely different hash function
+	// was used.
+	return subtle.ConstantTimeCompare(mac1, mac2) == 1
+}
diff --git a/contrib/go/_std_1.19/src/crypto/internal/boring/bbig/big.go b/contrib/go/_std_1.19/src/crypto/internal/boring/bbig/big.go
new file mode 100644
index 0000000000..5ce46972b3
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/internal/boring/bbig/big.go
@@ -0,0 +1,33 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bbig
+
+import (
+	"crypto/internal/boring"
+	"math/big"
+	"unsafe"
+)
+
+func Enc(b *big.Int) boring.BigInt {
+	if b == nil {
+		return nil
+	}
+	x := b.Bits()
+	if len(x) == 0 {
+		return boring.BigInt{}
+	}
+	return unsafe.Slice((*uint)(&x[0]), len(x))
+}
+
+func Dec(b boring.BigInt) *big.Int {
+	if b == nil {
+		return nil
+	}
+	if len(b) == 0 {
+		return new(big.Int)
+	}
+	x := unsafe.Slice((*big.Word)(&b[0]), len(b))
+	return new(big.Int).SetBits(x)
+}
diff --git a/contrib/go/_std_1.19/src/crypto/internal/boring/doc.go b/contrib/go/_std_1.19/src/crypto/internal/boring/doc.go
new file mode 100644
index 0000000000..6060fe5951
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/internal/boring/doc.go
@@ -0,0 +1,19 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package boring provides access to BoringCrypto implementation functions.
+// Check the constant Enabled to find out whether BoringCrypto is available.
+// If BoringCrypto is not available, the functions in this package all panic.
+package boring
+
+// Enabled reports whether BoringCrypto is available.
+// When enabled is false, all functions in this package panic.
+//
+// BoringCrypto is only available on linux/amd64 systems.
+const Enabled = available
+
+// A BigInt is the raw words from a BigInt.
+// This definition allows us to avoid importing math/big.
+// Conversion between BigInt and *big.Int is in crypto/internal/boring/bbig.
+type BigInt []uint
diff --git a/contrib/go/_std_1.19/src/crypto/internal/boring/notboring.go b/contrib/go/_std_1.19/src/crypto/internal/boring/notboring.go
new file mode 100644
index 0000000000..53096a68d1
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/internal/boring/notboring.go
@@ -0,0 +1,113 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !boringcrypto || !linux || !amd64 || !cgo || android || cmd_go_bootstrap || msan
+// +build !boringcrypto !linux !amd64 !cgo android cmd_go_bootstrap msan
+
+package boring
+
+import (
+	"crypto"
+	"crypto/cipher"
+	"crypto/internal/boring/sig"
+	"hash"
+)
+
+const available = false
+
+// Unreachable marks code that should be unreachable
+// when BoringCrypto is in use. It is a no-op without BoringCrypto.
+func Unreachable() {
+	// Code that's unreachable when using BoringCrypto
+	// is exactly the code we want to detect for reporting
+	// standard Go crypto.
+	sig.StandardCrypto()
+}
+
+// UnreachableExceptTests marks code that should be unreachable
+// when BoringCrypto is in use. It is a no-op without BoringCrypto.
+func UnreachableExceptTests() {}
+
+type randReader int
+
+func (randReader) Read(b []byte) (int, error) { panic("boringcrypto: not available") }
+
+const RandReader = randReader(0)
+
+func NewSHA1() hash.Hash   { panic("boringcrypto: not available") }
+func NewSHA224() hash.Hash { panic("boringcrypto: not available") }
+func NewSHA256() hash.Hash { panic("boringcrypto: not available") }
+func NewSHA384() hash.Hash { panic("boringcrypto: not available") }
+func NewSHA512() hash.Hash { panic("boringcrypto: not available") }
+
+func SHA1([]byte) [20]byte   { panic("boringcrypto: not available") }
+func SHA224([]byte) [28]byte { panic("boringcrypto: not available") }
+func SHA256([]byte) [32]byte { panic("boringcrypto: not available") }
+func SHA384([]byte) [48]byte { panic("boringcrypto: not available") }
+func SHA512([]byte) [64]byte { panic("boringcrypto: not available") }
+
+func NewHMAC(h func() hash.Hash, key []byte) hash.Hash { panic("boringcrypto: not available") }
+
+func NewAESCipher(key []byte) (cipher.Block, error) { panic("boringcrypto: not available") }
+func NewGCMTLS(cipher.Block) (cipher.AEAD, error)   { panic("boringcrypto: not available") }
+
+type PublicKeyECDSA struct{ _ int }
+type PrivateKeyECDSA struct{ _ int }
+
+func GenerateKeyECDSA(curve string) (X, Y, D BigInt, err error) {
+	panic("boringcrypto: not available")
+}
+func NewPrivateKeyECDSA(curve string, X, Y, D BigInt) (*PrivateKeyECDSA, error) {
+	panic("boringcrypto: not available")
+}
+func NewPublicKeyECDSA(curve string, X, Y BigInt) (*PublicKeyECDSA, error) {
+	panic("boringcrypto: not available")
+}
+func SignMarshalECDSA(priv *PrivateKeyECDSA, hash []byte) ([]byte, error) {
+	panic("boringcrypto: not available")
+}
+func VerifyECDSA(pub *PublicKeyECDSA, hash []byte, sig []byte) bool {
+	panic("boringcrypto: not available")
+}
+
+type PublicKeyRSA struct{ _ int }
+type PrivateKeyRSA struct{ _ int }
+
+func DecryptRSAOAEP(h hash.Hash, priv *PrivateKeyRSA, ciphertext, label []byte) ([]byte, error) {
+	panic("boringcrypto: not available")
+}
+func DecryptRSAPKCS1(priv *PrivateKeyRSA, ciphertext []byte) ([]byte, error) {
+	panic("boringcrypto: not available")
+}
+func DecryptRSANoPadding(priv *PrivateKeyRSA, ciphertext []byte) ([]byte, error) {
+	panic("boringcrypto: not available")
+}
+func EncryptRSAOAEP(h hash.Hash, pub *PublicKeyRSA, msg, label []byte) ([]byte, error) {
+	panic("boringcrypto: not available")
+}
+func EncryptRSAPKCS1(pub *PublicKeyRSA, msg []byte) ([]byte, error) {
+	panic("boringcrypto: not available")
+}
+func EncryptRSANoPadding(pub *PublicKeyRSA, msg []byte) ([]byte, error) {
+	panic("boringcrypto: not available")
+}
+func GenerateKeyRSA(bits int) (N, E, D, P, Q, Dp, Dq, Qinv BigInt, err error) {
+	panic("boringcrypto: not available")
+}
+func NewPrivateKeyRSA(N, E, D, P, Q, Dp, Dq, Qinv BigInt) (*PrivateKeyRSA, error) {
+	panic("boringcrypto: not available")
+}
+func NewPublicKeyRSA(N, E BigInt) (*PublicKeyRSA, error) { panic("boringcrypto: not available") }
+func SignRSAPKCS1v15(priv *PrivateKeyRSA, h crypto.Hash, hashed []byte) ([]byte, error) {
+	panic("boringcrypto: not available")
+}
+func SignRSAPSS(priv *PrivateKeyRSA, h crypto.Hash, hashed []byte, saltLen int) ([]byte, error) {
+	panic("boringcrypto: not available")
+}
+func VerifyRSAPKCS1v15(pub *PublicKeyRSA, h crypto.Hash, hashed, sig []byte) error {
+	panic("boringcrypto: not available")
+}
+func VerifyRSAPSS(pub *PublicKeyRSA, h crypto.Hash, hashed, sig []byte, saltLen int) error {
+	panic("boringcrypto: not available")
+}
diff --git a/contrib/go/_std_1.19/src/crypto/internal/boring/sig/sig.go b/contrib/go/_std_1.19/src/crypto/internal/boring/sig/sig.go
new file mode 100644
index 0000000000..716c03c5e9
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/internal/boring/sig/sig.go
@@ -0,0 +1,17 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package sig holds “code signatures” that can be called
+// and will result in certain code sequences being linked into
+// the final binary. The functions themselves are no-ops.
+package sig
+
+// BoringCrypto indicates that the BoringCrypto module is present.
+func BoringCrypto()
+
+// FIPSOnly indicates that package crypto/tls/fipsonly is present.
+func FIPSOnly()
+
+// StandardCrypto indicates that standard Go crypto is present.
+func StandardCrypto()
diff --git a/contrib/go/_std_1.19/src/crypto/internal/boring/sig/sig_amd64.s b/contrib/go/_std_1.19/src/crypto/internal/boring/sig/sig_amd64.s
new file mode 100644
index 0000000000..64e3462e4e
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/internal/boring/sig/sig_amd64.s
@@ -0,0 +1,54 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// These functions are no-ops, but you can search for their implementations
+// to find out whether they are linked into a particular binary.
+//
+// Each function consists of a two-byte jump over the next 29-bytes,
+// then a 5-byte indicator sequence unlikely to occur in real x86 instructions,
+// then a randomly-chosen 24-byte sequence, and finally a return instruction
+// (the target of the jump).
+//
+// These sequences are known to rsc.io/goversion.
+
+#define START \
+	BYTE $0xEB; BYTE $0x1D; BYTE $0xF4; BYTE $0x48; BYTE $0xF4; BYTE $0x4B; BYTE $0xF4
+
+#define END \
+	BYTE $0xC3
+
+// BoringCrypto indicates that BoringCrypto (in particular, its func init) is present.
+TEXT ·BoringCrypto(SB),NOSPLIT,$0
+	START
+	BYTE $0xB3; BYTE $0x32; BYTE $0xF5; BYTE $0x28;
+	BYTE $0x13; BYTE $0xA3; BYTE $0xB4; BYTE $0x50;
+	BYTE $0xD4; BYTE $0x41; BYTE $0xCC; BYTE $0x24;
+	BYTE $0x85; BYTE $0xF0; BYTE $0x01; BYTE $0x45;
+	BYTE $0x4E; BYTE $0x92; BYTE $0x10; BYTE $0x1B;
+	BYTE $0x1D; BYTE $0x2F; BYTE $0x19; BYTE $0x50;
+	END
+
+// StandardCrypto indicates that standard Go crypto is present.
+TEXT ·StandardCrypto(SB),NOSPLIT,$0
+	START
+	BYTE $0xba; BYTE $0xee; BYTE $0x4d; BYTE $0xfa;
+	BYTE $0x98; BYTE $0x51; BYTE $0xca; BYTE $0x56;
+	BYTE $0xa9; BYTE $0x11; BYTE $0x45; BYTE $0xe8;
+	BYTE $0x3e; BYTE $0x99; BYTE $0xc5; BYTE $0x9c;
+	BYTE $0xf9; BYTE $0x11; BYTE $0xcb; BYTE $0x8e;
+	BYTE $0x80; BYTE $0xda;  BYTE $0xf1; BYTE $0x2f;
+	END
+
+// FIPSOnly indicates that crypto/tls/fipsonly is present.
+TEXT ·FIPSOnly(SB),NOSPLIT,$0
+	START
+	BYTE $0x36; BYTE $0x3C; BYTE $0xB9; BYTE $0xCE;
+	BYTE $0x9D; BYTE $0x68; BYTE $0x04; BYTE $0x7D;
+	BYTE $0x31; BYTE $0xF2; BYTE $0x8D; BYTE $0x32;
+	BYTE $0x5D; BYTE $0x5C; BYTE $0xA5; BYTE $0x87;
+	BYTE $0x3F; BYTE $0x5D; BYTE $0x80; BYTE $0xCA;
+	BYTE $0xF6; BYTE $0xD6; BYTE $0x15; BYTE $0x1B;
+	END
diff --git a/contrib/go/_std_1.19/src/crypto/internal/edwards25519/doc.go b/contrib/go/_std_1.19/src/crypto/internal/edwards25519/doc.go
new file mode 100644
index 0000000000..8cba6febfe
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/internal/edwards25519/doc.go
@@ -0,0 +1,22 @@
+// Copyright (c) 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package edwards25519 implements group logic for the twisted Edwards curve
+//
+//	-x^2 + y^2 = 1 + -(121665/121666)*x^2*y^2
+//
+// This is better known as the Edwards curve equivalent to Curve25519, and is
+// the curve used by the Ed25519 signature scheme.
+//
+// Most users don't need this package, and should instead use crypto/ed25519 for
+// signatures, golang.org/x/crypto/curve25519 for Diffie-Hellman, or
+// github.com/gtank/ristretto255 for prime order group logic.
+//
+// However, developers who do need to interact with low-level edwards25519
+// operations can use filippo.io/edwards25519, an extended version of this
+// package repackaged as an importable module.
+//
+// (Note that filippo.io/edwards25519 and github.com/gtank/ristretto255 are not
+// maintained by the Go team and are not covered by the Go 1 Compatibility Promise.)
+package edwards25519
diff --git a/contrib/go/_std_1.19/src/crypto/internal/edwards25519/edwards25519.go b/contrib/go/_std_1.19/src/crypto/internal/edwards25519/edwards25519.go
new file mode 100644
index 0000000000..71e9c097a9
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/internal/edwards25519/edwards25519.go
@@ -0,0 +1,426 @@
+// Copyright (c) 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package edwards25519
+
+import (
+	"crypto/internal/edwards25519/field"
+	"errors"
+)
+
+// Point types.
+
+type projP1xP1 struct {
+	X, Y, Z, T field.Element
+}
+
+type projP2 struct {
+	X, Y, Z field.Element
+}
+
+// Point represents a point on the edwards25519 curve.
+//
+// This type works similarly to math/big.Int, and all arguments and receivers
+// are allowed to alias.
+//
+// The zero value is NOT valid, and it may be used only as a receiver.
+type Point struct {
+	// The point is internally represented in extended coordinates (X, Y, Z, T)
+	// where x = X/Z, y = Y/Z, and xy = T/Z per https://eprint.iacr.org/2008/522.
+	x, y, z, t field.Element
+
+	// Make the type not comparable (i.e. used with == or as a map key), as
+	// equivalent points can be represented by different Go values.
+	_ incomparable
+}
+
+type incomparable [0]func()
+
+func checkInitialized(points ...*Point) {
+	for _, p := range points {
+		if p.x == (field.Element{}) && p.y == (field.Element{}) {
+			panic("edwards25519: use of uninitialized Point")
+		}
+	}
+}
+
+type projCached struct {
+	YplusX, YminusX, Z, T2d field.Element
+}
+
+type affineCached struct {
+	YplusX, YminusX, T2d field.Element
+}
+
+// Constructors.
+
+func (v *projP2) Zero() *projP2 {
+	v.X.Zero()
+	v.Y.One()
+	v.Z.One()
+	return v
+}
+
+// identity is the point at infinity.
+var identity, _ = new(Point).SetBytes([]byte{
+	1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0})
+
+// NewIdentityPoint returns a new Point set to the identity.
+func NewIdentityPoint() *Point {
+	return new(Point).Set(identity)
+}
+
+// generator is the canonical curve basepoint. See TestGenerator for the
+// correspondence of this encoding with the values in RFC 8032.
+var generator, _ = new(Point).SetBytes([]byte{
+	0x58, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66,
+	0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66,
+	0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66,
+	0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66})
+
+// NewGeneratorPoint returns a new Point set to the canonical generator.
+func NewGeneratorPoint() *Point {
+	return new(Point).Set(generator)
+}
+
+func (v *projCached) Zero() *projCached {
+	v.YplusX.One()
+	v.YminusX.One()
+	v.Z.One()
+	v.T2d.Zero()
+	return v
+}
+
+func (v *affineCached) Zero() *affineCached {
+	v.YplusX.One()
+	v.YminusX.One()
+	v.T2d.Zero()
+	return v
+}
+
+// Assignments.
+
+// Set sets v = u, and returns v.
+func (v *Point) Set(u *Point) *Point {
+	*v = *u
+	return v
+}
+
+// Encoding.
+
+// Bytes returns the canonical 32-byte encoding of v, according to RFC 8032,
+// Section 5.1.2.
+func (v *Point) Bytes() []byte {
+	// This function is outlined to make the allocations inline in the caller
+	// rather than happen on the heap.
+	var buf [32]byte
+	return v.bytes(&buf)
+}
+
+func (v *Point) bytes(buf *[32]byte) []byte {
+	checkInitialized(v)
+
+	var zInv, x, y field.Element
+	zInv.Invert(&v.z)       // zInv = 1 / Z
+	x.Multiply(&v.x, &zInv) // x = X / Z
+	y.Multiply(&v.y, &zInv) // y = Y / Z
+
+	out := copyFieldElement(buf, &y)
+	out[31] |= byte(x.IsNegative() << 7)
+	return out
+}
+
+var feOne = new(field.Element).One()
+
+// SetBytes sets v = x, where x is a 32-byte encoding of v. If x does not
+// represent a valid point on the curve, SetBytes returns nil and an error and
+// the receiver is unchanged. Otherwise, SetBytes returns v.
+//
+// Note that SetBytes accepts all non-canonical encodings of valid points.
+// That is, it follows decoding rules that match most implementations in
+// the ecosystem rather than RFC 8032.
+func (v *Point) SetBytes(x []byte) (*Point, error) {
+	// Specifically, the non-canonical encodings that are accepted are
+	//   1) the ones where the field element is not reduced (see the
+	//      (*field.Element).SetBytes docs) and
+	//   2) the ones where the x-coordinate is zero and the sign bit is set.
+	//
+	// Read more at https://hdevalence.ca/blog/2020-10-04-its-25519am,
+	// specifically the "Canonical A, R" section.
+
+	y, err := new(field.Element).SetBytes(x)
+	if err != nil {
+		return nil, errors.New("edwards25519: invalid point encoding length")
+	}
+
+	// -x² + y² = 1 + dx²y²
+	// x² + dx²y² = x²(dy² + 1) = y² - 1
+	// x² = (y² - 1) / (dy² + 1)
+
+	// u = y² - 1
+	y2 := new(field.Element).Square(y)
+	u := new(field.Element).Subtract(y2, feOne)
+
+	// v = dy² + 1
+	vv := new(field.Element).Multiply(y2, d)
+	vv = vv.Add(vv, feOne)
+
+	// x = +√(u/v)
+	xx, wasSquare := new(field.Element).SqrtRatio(u, vv)
+	if wasSquare == 0 {
+		return nil, errors.New("edwards25519: invalid point encoding")
+	}
+
+	// Select the negative square root if the sign bit is set.
+	xxNeg := new(field.Element).Negate(xx)
+	xx = xx.Select(xxNeg, xx, int(x[31]>>7))
+
+	v.x.Set(xx)
+	v.y.Set(y)
+	v.z.One()
+	v.t.Multiply(xx, y) // xy = T / Z
+
+	return v, nil
+}
+
+func copyFieldElement(buf *[32]byte, v *field.Element) []byte {
+	copy(buf[:], v.Bytes())
+	return buf[:]
+}
+
+// Conversions.
+
+func (v *projP2) FromP1xP1(p *projP1xP1) *projP2 {
+	v.X.Multiply(&p.X, &p.T)
+	v.Y.Multiply(&p.Y, &p.Z)
+	v.Z.Multiply(&p.Z, &p.T)
+	return v
+}
+
+func (v *projP2) FromP3(p *Point) *projP2 {
+	v.X.Set(&p.x)
+	v.Y.Set(&p.y)
+	v.Z.Set(&p.z)
+	return v
+}
+
+func (v *Point) fromP1xP1(p *projP1xP1) *Point {
+	v.x.Multiply(&p.X, &p.T)
+	v.y.Multiply(&p.Y, &p.Z)
+	v.z.Multiply(&p.Z, &p.T)
+	v.t.Multiply(&p.X, &p.Y)
+	return v
+}
+
+func (v *Point) fromP2(p *projP2) *Point {
+	v.x.Multiply(&p.X, &p.Z)
+	v.y.Multiply(&p.Y, &p.Z)
+	v.z.Square(&p.Z)
+	v.t.Multiply(&p.X, &p.Y)
+	return v
+}
+
+// d is a constant in the curve equation.
+var d, _ = new(field.Element).SetBytes([]byte{
+	0xa3, 0x78, 0x59, 0x13, 0xca, 0x4d, 0xeb, 0x75,
+	0xab, 0xd8, 0x41, 0x41, 0x4d, 0x0a, 0x70, 0x00,
+	0x98, 0xe8, 0x79, 0x77, 0x79, 0x40, 0xc7, 0x8c,
+	0x73, 0xfe, 0x6f, 0x2b, 0xee, 0x6c, 0x03, 0x52})
+var d2 = new(field.Element).Add(d, d)
+
+func (v *projCached) FromP3(p *Point) *projCached {
+	v.YplusX.Add(&p.y, &p.x)
+	v.YminusX.Subtract(&p.y, &p.x)
+	v.Z.Set(&p.z)
+	v.T2d.Multiply(&p.t, d2)
+	return v
+}
+
+func (v *affineCached) FromP3(p *Point) *affineCached {
+	v.YplusX.Add(&p.y, &p.x)
+	v.YminusX.Subtract(&p.y, &p.x)
+	v.T2d.Multiply(&p.t, d2)
+
+	var invZ field.Element
+	invZ.Invert(&p.z)
+	v.YplusX.Multiply(&v.YplusX, &invZ)
+	v.YminusX.Multiply(&v.YminusX, &invZ)
+	v.T2d.Multiply(&v.T2d, &invZ)
+	return v
+}
+
+// (Re)addition and subtraction.
+
+// Add sets v = p + q, and returns v.
+func (v *Point) Add(p, q *Point) *Point {
+	checkInitialized(p, q)
+	qCached := new(projCached).FromP3(q)
+	result := new(projP1xP1).Add(p, qCached)
+	return v.fromP1xP1(result)
+}
+
+// Subtract sets v = p - q, and returns v.
+func (v *Point) Subtract(p, q *Point) *Point {
+	checkInitialized(p, q)
+	qCached := new(projCached).FromP3(q)
+	result := new(projP1xP1).Sub(p, qCached)
+	return v.fromP1xP1(result)
+}
+
+func (v *projP1xP1) Add(p *Point, q *projCached) *projP1xP1 {
+	var YplusX, YminusX, PP, MM, TT2d, ZZ2 field.Element
+
+	YplusX.Add(&p.y, &p.x)
+	YminusX.Subtract(&p.y, &p.x)
+
+	PP.Multiply(&YplusX, &q.YplusX)
+	MM.Multiply(&YminusX, &q.YminusX)
+	TT2d.Multiply(&p.t, &q.T2d)
+	ZZ2.Multiply(&p.z, &q.Z)
+
+	ZZ2.Add(&ZZ2, &ZZ2)
+
+	v.X.Subtract(&PP, &MM)
+	v.Y.Add(&PP, &MM)
+	v.Z.Add(&ZZ2, &TT2d)
+	v.T.Subtract(&ZZ2, &TT2d)
+	return v
+}
+
+func (v *projP1xP1) Sub(p *Point, q *projCached) *projP1xP1 {
+	var YplusX, YminusX, PP, MM, TT2d, ZZ2 field.Element
+
+	YplusX.Add(&p.y, &p.x)
+	YminusX.Subtract(&p.y, &p.x)
+
+	PP.Multiply(&YplusX, &q.YminusX) // flipped sign
+	MM.Multiply(&YminusX, &q.YplusX) // flipped sign
+	TT2d.Multiply(&p.t, &q.T2d)
+	ZZ2.Multiply(&p.z, &q.Z)
+
+	ZZ2.Add(&ZZ2, &ZZ2)
+
+	v.X.Subtract(&PP, &MM)
+	v.Y.Add(&PP, &MM)
+	v.Z.Subtract(&ZZ2, &TT2d) // flipped sign
+	v.T.Add(&ZZ2, &TT2d)      // flipped sign
+	return v
+}
+
+func (v *projP1xP1) AddAffine(p *Point, q *affineCached) *projP1xP1 {
+	var YplusX, YminusX, PP, MM, TT2d, Z2 field.Element
+
+	YplusX.Add(&p.y, &p.x)
+	YminusX.Subtract(&p.y, &p.x)
+
+	PP.Multiply(&YplusX, &q.YplusX)
+	MM.Multiply(&YminusX, &q.YminusX)
+	TT2d.Multiply(&p.t, &q.T2d)
+
+	Z2.Add(&p.z, &p.z)
+
+	v.X.Subtract(&PP, &MM)
+	v.Y.Add(&PP, &MM)
+	v.Z.Add(&Z2, &TT2d)
+	v.T.Subtract(&Z2, &TT2d)
+	return v
+}
+
+func (v *projP1xP1) SubAffine(p *Point, q *affineCached) *projP1xP1 {
+	var YplusX, YminusX, PP, MM, TT2d, Z2 field.Element
+
+	YplusX.Add(&p.y, &p.x)
+	YminusX.Subtract(&p.y, &p.x)
+
+	PP.Multiply(&YplusX, &q.YminusX) // flipped sign
+	MM.Multiply(&YminusX, &q.YplusX) // flipped sign
+	TT2d.Multiply(&p.t, &q.T2d)
+
+	Z2.Add(&p.z, &p.z)
+
+	v.X.Subtract(&PP, &MM)
+	v.Y.Add(&PP, &MM)
+	v.Z.Subtract(&Z2, &TT2d) // flipped sign
+	v.T.Add(&Z2, &TT2d)      // flipped sign
+	return v
+}
+
+// Doubling.
+
+func (v *projP1xP1) Double(p *projP2) *projP1xP1 {
+	var XX, YY, ZZ2, XplusYsq field.Element
+
+	XX.Square(&p.X)
+	YY.Square(&p.Y)
+	ZZ2.Square(&p.Z)
+	ZZ2.Add(&ZZ2, &ZZ2)
+	XplusYsq.Add(&p.X, &p.Y)
+	XplusYsq.Square(&XplusYsq)
+
+	v.Y.Add(&YY, &XX)
+	v.Z.Subtract(&YY, &XX)
+
+	v.X.Subtract(&XplusYsq, &v.Y)
+	v.T.Subtract(&ZZ2, &v.Z)
+	return v
+}
+
+// Negation.
+
+// Negate sets v = -p, and returns v.
+func (v *Point) Negate(p *Point) *Point {
+	checkInitialized(p)
+	v.x.Negate(&p.x)
+	v.y.Set(&p.y)
+	v.z.Set(&p.z)
+	v.t.Negate(&p.t)
+	return v
+}
+
+// Equal returns 1 if v is equivalent to u, and 0 otherwise.
+func (v *Point) Equal(u *Point) int {
+	checkInitialized(v, u)
+
+	var t1, t2, t3, t4 field.Element
+	t1.Multiply(&v.x, &u.z)
+	t2.Multiply(&u.x, &v.z)
+	t3.Multiply(&v.y, &u.z)
+	t4.Multiply(&u.y, &v.z)
+
+	return t1.Equal(&t2) & t3.Equal(&t4)
+}
+
+// Constant-time operations
+
+// Select sets v to a if cond == 1 and to b if cond == 0.
+func (v *projCached) Select(a, b *projCached, cond int) *projCached {
+	v.YplusX.Select(&a.YplusX, &b.YplusX, cond)
+	v.YminusX.Select(&a.YminusX, &b.YminusX, cond)
+	v.Z.Select(&a.Z, &b.Z, cond)
+	v.T2d.Select(&a.T2d, &b.T2d, cond)
+	return v
+}
+
+// Select sets v to a if cond == 1 and to b if cond == 0.
+func (v *affineCached) Select(a, b *affineCached, cond int) *affineCached {
+	v.YplusX.Select(&a.YplusX, &b.YplusX, cond)
+	v.YminusX.Select(&a.YminusX, &b.YminusX, cond)
+	v.T2d.Select(&a.T2d, &b.T2d, cond)
+	return v
+}
+
+// CondNeg negates v if cond == 1 and leaves it unchanged if cond == 0.
+func (v *projCached) CondNeg(cond int) *projCached {
+	v.YplusX.Swap(&v.YminusX, cond)
+	v.T2d.Select(new(field.Element).Negate(&v.T2d), &v.T2d, cond)
+	return v
+}
+
+// CondNeg negates v if cond == 1 and leaves it unchanged if cond == 0.
+func (v *affineCached) CondNeg(cond int) *affineCached {
+	v.YplusX.Swap(&v.YminusX, cond)
+	v.T2d.Select(new(field.Element).Negate(&v.T2d), &v.T2d, cond)
+	return v
+}
diff --git a/contrib/go/_std_1.19/src/crypto/internal/edwards25519/field/fe.go b/contrib/go/_std_1.19/src/crypto/internal/edwards25519/field/fe.go
new file mode 100644
index 0000000000..5518ef2b90
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/internal/edwards25519/field/fe.go
@@ -0,0 +1,420 @@
+// Copyright (c) 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package field implements fast arithmetic modulo 2^255-19.
+package field
+
+import (
+	"crypto/subtle"
+	"encoding/binary"
+	"errors"
+	"math/bits"
+)
+
+// Element represents an element of the field GF(2^255-19). Note that this
+// is not a cryptographically secure group, and should only be used to interact
+// with edwards25519.Point coordinates.
+//
+// This type works similarly to math/big.Int, and all arguments and receivers
+// are allowed to alias.
+//
+// The zero value is a valid zero element.
+type Element struct {
+	// An element t represents the integer
+	//     t.l0 + t.l1*2^51 + t.l2*2^102 + t.l3*2^153 + t.l4*2^204
+	//
+	// Between operations, all limbs are expected to be lower than 2^52.
+	l0 uint64
+	l1 uint64
+	l2 uint64
+	l3 uint64
+	l4 uint64
+}
+
+const maskLow51Bits uint64 = (1 << 51) - 1
+
+var feZero = &Element{0, 0, 0, 0, 0}
+
+// Zero sets v = 0, and returns v.
+func (v *Element) Zero() *Element {
+	*v = *feZero
+	return v
+}
+
+var feOne = &Element{1, 0, 0, 0, 0}
+
+// One sets v = 1, and returns v.
+func (v *Element) One() *Element {
+	*v = *feOne
+	return v
+}
+
+// reduce reduces v modulo 2^255 - 19 and returns it.
+func (v *Element) reduce() *Element {
+	v.carryPropagate()
+
+	// After the light reduction we now have a field element representation
+	// v < 2^255 + 2^13 * 19, but need v < 2^255 - 19.
+
+	// If v >= 2^255 - 19, then v + 19 >= 2^255, which would overflow 2^255 - 1,
+	// generating a carry. That is, c will be 0 if v < 2^255 - 19, and 1 otherwise.
+	c := (v.l0 + 19) >> 51
+	c = (v.l1 + c) >> 51
+	c = (v.l2 + c) >> 51
+	c = (v.l3 + c) >> 51
+	c = (v.l4 + c) >> 51
+
+	// If v < 2^255 - 19 and c = 0, this will be a no-op. Otherwise, it's
+	// effectively applying the reduction identity to the carry.
+	v.l0 += 19 * c
+
+	v.l1 += v.l0 >> 51
+	v.l0 = v.l0 & maskLow51Bits
+	v.l2 += v.l1 >> 51
+	v.l1 = v.l1 & maskLow51Bits
+	v.l3 += v.l2 >> 51
+	v.l2 = v.l2 & maskLow51Bits
+	v.l4 += v.l3 >> 51
+	v.l3 = v.l3 & maskLow51Bits
+	// no additional carry
+	v.l4 = v.l4 & maskLow51Bits
+
+	return v
+}
+
+// Add sets v = a + b, and returns v.
+func (v *Element) Add(a, b *Element) *Element {
+	v.l0 = a.l0 + b.l0
+	v.l1 = a.l1 + b.l1
+	v.l2 = a.l2 + b.l2
+	v.l3 = a.l3 + b.l3
+	v.l4 = a.l4 + b.l4
+	// Using the generic implementation here is actually faster than the
+	// assembly. Probably because the body of this function is so simple that
+	// the compiler can figure out better optimizations by inlining the carry
+	// propagation.
+	return v.carryPropagateGeneric()
+}
+
+// Subtract sets v = a - b, and returns v.
+func (v *Element) Subtract(a, b *Element) *Element {
+	// We first add 2 * p, to guarantee the subtraction won't underflow, and
+	// then subtract b (which can be up to 2^255 + 2^13 * 19).
+	v.l0 = (a.l0 + 0xFFFFFFFFFFFDA) - b.l0
+	v.l1 = (a.l1 + 0xFFFFFFFFFFFFE) - b.l1
+	v.l2 = (a.l2 + 0xFFFFFFFFFFFFE) - b.l2
+	v.l3 = (a.l3 + 0xFFFFFFFFFFFFE) - b.l3
+	v.l4 = (a.l4 + 0xFFFFFFFFFFFFE) - b.l4
+	return v.carryPropagate()
+}
+
+// Negate sets v = -a, and returns v.
+func (v *Element) Negate(a *Element) *Element {
+	return v.Subtract(feZero, a)
+}
+
+// Invert sets v = 1/z mod p, and returns v.
+//
+// If z == 0, Invert returns v = 0.
+func (v *Element) Invert(z *Element) *Element {
+	// Inversion is implemented as exponentiation with exponent p − 2. It uses the
+	// same sequence of 255 squarings and 11 multiplications as [Curve25519].
+	var z2, z9, z11, z2_5_0, z2_10_0, z2_20_0, z2_50_0, z2_100_0, t Element
+
+	z2.Square(z)             // 2
+	t.Square(&z2)            // 4
+	t.Square(&t)             // 8
+	z9.Multiply(&t, z)       // 9
+	z11.Multiply(&z9, &z2)   // 11
+	t.Square(&z11)           // 22
+	z2_5_0.Multiply(&t, &z9) // 31 = 2^5 - 2^0
+
+	t.Square(&z2_5_0) // 2^6 - 2^1
+	for i := 0; i < 4; i++ {
+		t.Square(&t) // 2^10 - 2^5
+	}
+	z2_10_0.Multiply(&t, &z2_5_0) // 2^10 - 2^0
+
+	t.Square(&z2_10_0) // 2^11 - 2^1
+	for i := 0; i < 9; i++ {
+		t.Square(&t) // 2^20 - 2^10
+	}
+	z2_20_0.Multiply(&t, &z2_10_0) // 2^20 - 2^0
+
+	t.Square(&z2_20_0) // 2^21 - 2^1
+	for i := 0; i < 19; i++ {
+		t.Square(&t) // 2^40 - 2^20
+	}
+	t.Multiply(&t, &z2_20_0) // 2^40 - 2^0
+
+	t.Square(&t) // 2^41 - 2^1
+	for i := 0; i < 9; i++ {
+		t.Square(&t) // 2^50 - 2^10
+	}
+	z2_50_0.Multiply(&t, &z2_10_0) // 2^50 - 2^0
+
+	t.Square(&z2_50_0) // 2^51 - 2^1
+	for i := 0; i < 49; i++ {
+		t.Square(&t) // 2^100 - 2^50
+	}
+	z2_100_0.Multiply(&t, &z2_50_0) // 2^100 - 2^0
+
+	t.Square(&z2_100_0) // 2^101 - 2^1
+	for i := 0; i < 99; i++ {
+		t.Square(&t) // 2^200 - 2^100
+	}
+	t.Multiply(&t, &z2_100_0) // 2^200 - 2^0
+
+	t.Square(&t) // 2^201 - 2^1
+	for i := 0; i < 49; i++ {
+		t.Square(&t) // 2^250 - 2^50
+	}
+	t.Multiply(&t, &z2_50_0) // 2^250 - 2^0
+
+	t.Square(&t) // 2^251 - 2^1
+	t.Square(&t) // 2^252 - 2^2
+	t.Square(&t) // 2^253 - 2^3
+	t.Square(&t) // 2^254 - 2^4
+	t.Square(&t) // 2^255 - 2^5
+
+	return v.Multiply(&t, &z11) // 2^255 - 21
+}
+
+// Set sets v = a, and returns v.
+func (v *Element) Set(a *Element) *Element {
+	*v = *a
+	return v
+}
+
+// SetBytes sets v to x, where x is a 32-byte little-endian encoding. If x is
+// not of the right length, SetBytes returns nil and an error, and the
+// receiver is unchanged.
+//
+// Consistent with RFC 7748, the most significant bit (the high bit of the
+// last byte) is ignored, and non-canonical values (2^255-19 through 2^255-1)
+// are accepted. Note that this is laxer than specified by RFC 8032, but
+// consistent with most Ed25519 implementations.
+func (v *Element) SetBytes(x []byte) (*Element, error) {
+	if len(x) != 32 {
+		return nil, errors.New("edwards25519: invalid field element input size")
+	}
+
+	// Bits 0:51 (bytes 0:8, bits 0:64, shift 0, mask 51).
+	v.l0 = binary.LittleEndian.Uint64(x[0:8])
+	v.l0 &= maskLow51Bits
+	// Bits 51:102 (bytes 6:14, bits 48:112, shift 3, mask 51).
+	v.l1 = binary.LittleEndian.Uint64(x[6:14]) >> 3
+	v.l1 &= maskLow51Bits
+	// Bits 102:153 (bytes 12:20, bits 96:160, shift 6, mask 51).
+	v.l2 = binary.LittleEndian.Uint64(x[12:20]) >> 6
+	v.l2 &= maskLow51Bits
+	// Bits 153:204 (bytes 19:27, bits 152:216, shift 1, mask 51).
+	v.l3 = binary.LittleEndian.Uint64(x[19:27]) >> 1
+	v.l3 &= maskLow51Bits
+	// Bits 204:255 (bytes 24:32, bits 192:256, shift 12, mask 51).
+	// Note: not bytes 25:33, shift 4, to avoid overread.
+	v.l4 = binary.LittleEndian.Uint64(x[24:32]) >> 12
+	v.l4 &= maskLow51Bits
+
+	return v, nil
+}
+
+// Bytes returns the canonical 32-byte little-endian encoding of v.
+func (v *Element) Bytes() []byte {
+	// This function is outlined to make the allocations inline in the caller
+	// rather than happen on the heap.
+	var out [32]byte
+	return v.bytes(&out)
+}
+
+func (v *Element) bytes(out *[32]byte) []byte {
+	t := *v
+	t.reduce()
+
+	var buf [8]byte
+	for i, l := range [5]uint64{t.l0, t.l1, t.l2, t.l3, t.l4} {
+		bitsOffset := i * 51
+		binary.LittleEndian.PutUint64(buf[:], l<<uint(bitsOffset%8))
+		for i, bb := range buf {
+			off := bitsOffset/8 + i
+			if off >= len(out) {
+				break
+			}
+			out[off] |= bb
+		}
+	}
+
+	return out[:]
+}
+
+// Equal returns 1 if v and u are equal, and 0 otherwise.
+func (v *Element) Equal(u *Element) int {
+	sa, sv := u.Bytes(), v.Bytes()
+	return subtle.ConstantTimeCompare(sa, sv)
+}
+
+// mask64Bits returns 0xffffffff if cond is 1, and 0 otherwise.
+func mask64Bits(cond int) uint64 { return ^(uint64(cond) - 1) }
+
+// Select sets v to a if cond == 1, and to b if cond == 0.
+func (v *Element) Select(a, b *Element, cond int) *Element {
+	m := mask64Bits(cond)
+	v.l0 = (m & a.l0) | (^m & b.l0)
+	v.l1 = (m & a.l1) | (^m & b.l1)
+	v.l2 = (m & a.l2) | (^m & b.l2)
+	v.l3 = (m & a.l3) | (^m & b.l3)
+	v.l4 = (m & a.l4) | (^m & b.l4)
+	return v
+}
+
+// Swap swaps v and u if cond == 1 or leaves them unchanged if cond == 0, and returns v.
+func (v *Element) Swap(u *Element, cond int) {
+	m := mask64Bits(cond)
+	t := m & (v.l0 ^ u.l0)
+	v.l0 ^= t
+	u.l0 ^= t
+	t = m & (v.l1 ^ u.l1)
+	v.l1 ^= t
+	u.l1 ^= t
+	t = m & (v.l2 ^ u.l2)
+	v.l2 ^= t
+	u.l2 ^= t
+	t = m & (v.l3 ^ u.l3)
+	v.l3 ^= t
+	u.l3 ^= t
+	t = m & (v.l4 ^ u.l4)
+	v.l4 ^= t
+	u.l4 ^= t
+}
+
+// IsNegative returns 1 if v is negative, and 0 otherwise.
+func (v *Element) IsNegative() int {
+	return int(v.Bytes()[0] & 1)
+}
+
+// Absolute sets v to |u|, and returns v.
+func (v *Element) Absolute(u *Element) *Element {
+	return v.Select(new(Element).Negate(u), u, u.IsNegative())
+}
+
+// Multiply sets v = x * y, and returns v.
+func (v *Element) Multiply(x, y *Element) *Element {
+	feMul(v, x, y)
+	return v
+}
+
+// Square sets v = x * x, and returns v.
+func (v *Element) Square(x *Element) *Element {
+	feSquare(v, x)
+	return v
+}
+
+// Mult32 sets v = x * y, and returns v.
+func (v *Element) Mult32(x *Element, y uint32) *Element {
+	x0lo, x0hi := mul51(x.l0, y)
+	x1lo, x1hi := mul51(x.l1, y)
+	x2lo, x2hi := mul51(x.l2, y)
+	x3lo, x3hi := mul51(x.l3, y)
+	x4lo, x4hi := mul51(x.l4, y)
+	v.l0 = x0lo + 19*x4hi // carried over per the reduction identity
+	v.l1 = x1lo + x0hi
+	v.l2 = x2lo + x1hi
+	v.l3 = x3lo + x2hi
+	v.l4 = x4lo + x3hi
+	// The hi portions are going to be only 32 bits, plus any previous excess,
+	// so we can skip the carry propagation.
+	return v
+}
+
+// mul51 returns lo + hi * 2⁵¹ = a * b.
+func mul51(a uint64, b uint32) (lo uint64, hi uint64) {
+	mh, ml := bits.Mul64(a, uint64(b))
+	lo = ml & maskLow51Bits
+	hi = (mh << 13) | (ml >> 51)
+	return
+}
+
+// Pow22523 set v = x^((p-5)/8), and returns v. (p-5)/8 is 2^252-3.
+func (v *Element) Pow22523(x *Element) *Element {
+	var t0, t1, t2 Element
+
+	t0.Square(x)             // x^2
+	t1.Square(&t0)           // x^4
+	t1.Square(&t1)           // x^8
+	t1.Multiply(x, &t1)      // x^9
+	t0.Multiply(&t0, &t1)    // x^11
+	t0.Square(&t0)           // x^22
+	t0.Multiply(&t1, &t0)    // x^31
+	t1.Square(&t0)           // x^62
+	for i := 1; i < 5; i++ { // x^992
+		t1.Square(&t1)
+	}
+	t0.Multiply(&t1, &t0)     // x^1023 -> 1023 = 2^10 - 1
+	t1.Square(&t0)            // 2^11 - 2
+	for i := 1; i < 10; i++ { // 2^20 - 2^10
+		t1.Square(&t1)
+	}
+	t1.Multiply(&t1, &t0)     // 2^20 - 1
+	t2.Square(&t1)            // 2^21 - 2
+	for i := 1; i < 20; i++ { // 2^40 - 2^20
+		t2.Square(&t2)
+	}
+	t1.Multiply(&t2, &t1)     // 2^40 - 1
+	t1.Square(&t1)            // 2^41 - 2
+	for i := 1; i < 10; i++ { // 2^50 - 2^10
+		t1.Square(&t1)
+	}
+	t0.Multiply(&t1, &t0)     // 2^50 - 1
+	t1.Square(&t0)            // 2^51 - 2
+	for i := 1; i < 50; i++ { // 2^100 - 2^50
+		t1.Square(&t1)
+	}
+	t1.Multiply(&t1, &t0)      // 2^100 - 1
+	t2.Square(&t1)             // 2^101 - 2
+	for i := 1; i < 100; i++ { // 2^200 - 2^100
+		t2.Square(&t2)
+	}
+	t1.Multiply(&t2, &t1)     // 2^200 - 1
+	t1.Square(&t1)            // 2^201 - 2
+	for i := 1; i < 50; i++ { // 2^250 - 2^50
+		t1.Square(&t1)
+	}
+	t0.Multiply(&t1, &t0)     // 2^250 - 1
+	t0.Square(&t0)            // 2^251 - 2
+	t0.Square(&t0)            // 2^252 - 4
+	return v.Multiply(&t0, x) // 2^252 - 3 -> x^(2^252-3)
+}
+
+// sqrtM1 is 2^((p-1)/4), which squared is equal to -1 by Euler's Criterion.
+var sqrtM1 = &Element{1718705420411056, 234908883556509,
+	2233514472574048, 2117202627021982, 765476049583133}
+
+// SqrtRatio sets r to the non-negative square root of the ratio of u and v.
+//
+// If u/v is square, SqrtRatio returns r and 1. If u/v is not square, SqrtRatio
+// sets r according to Section 4.3 of draft-irtf-cfrg-ristretto255-decaf448-00,
+// and returns r and 0.
+func (r *Element) SqrtRatio(u, v *Element) (R *Element, wasSquare int) {
+	t0 := new(Element)
+
+	// r = (u * v3) * (u * v7)^((p-5)/8)
+	v2 := new(Element).Square(v)
+	uv3 := new(Element).Multiply(u, t0.Multiply(v2, v))
+	uv7 := new(Element).Multiply(uv3, t0.Square(v2))
+	rr := new(Element).Multiply(uv3, t0.Pow22523(uv7))
+
+	check := new(Element).Multiply(v, t0.Square(rr)) // check = v * r^2
+
+	uNeg := new(Element).Negate(u)
+	correctSignSqrt := check.Equal(u)
+	flippedSignSqrt := check.Equal(uNeg)
+	flippedSignSqrtI := check.Equal(t0.Multiply(uNeg, sqrtM1))
+
+	rPrime := new(Element).Multiply(rr, sqrtM1) // r_prime = SQRT_M1 * r
+	// r = CT_SELECT(r_prime IF flipped_sign_sqrt | flipped_sign_sqrt_i ELSE r)
+	rr.Select(rPrime, rr, flippedSignSqrt|flippedSignSqrtI)
+
+	r.Absolute(rr) // Choose the nonnegative square root.
+	return r, correctSignSqrt | flippedSignSqrt
+}
diff --git a/contrib/go/_std_1.19/src/crypto/internal/edwards25519/field/fe_amd64.go b/contrib/go/_std_1.19/src/crypto/internal/edwards25519/field/fe_amd64.go
new file mode 100644
index 0000000000..70c541692c
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/internal/edwards25519/field/fe_amd64.go
@@ -0,0 +1,15 @@
+// Code generated by command: go run fe_amd64_asm.go -out ../fe_amd64.s -stubs ../fe_amd64.go -pkg field. DO NOT EDIT.
+
+//go:build amd64 && gc && !purego
+
+package field
+
+// feMul sets out = a * b. It works like feMulGeneric.
+//
+//go:noescape
+func feMul(out *Element, a *Element, b *Element)
+
+// feSquare sets out = a * a. It works like feSquareGeneric.
+//
+//go:noescape
+func feSquare(out *Element, a *Element)
diff --git a/contrib/go/_std_1.18/src/crypto/ed25519/internal/edwards25519/field/fe_amd64.s b/contrib/go/_std_1.19/src/crypto/internal/edwards25519/field/fe_amd64.s
index 0aa1e86d98..0aa1e86d98 100644
--- a/contrib/go/_std_1.18/src/crypto/ed25519/internal/edwards25519/field/fe_amd64.s
+++ b/contrib/go/_std_1.19/src/crypto/internal/edwards25519/field/fe_amd64.s
diff --git a/contrib/go/_std_1.18/src/crypto/ed25519/internal/edwards25519/field/fe_arm64_noasm.go b/contrib/go/_std_1.19/src/crypto/internal/edwards25519/field/fe_arm64_noasm.go
index fc029ac12d..fc029ac12d 100644
--- a/contrib/go/_std_1.18/src/crypto/ed25519/internal/edwards25519/field/fe_arm64_noasm.go
+++ b/contrib/go/_std_1.19/src/crypto/internal/edwards25519/field/fe_arm64_noasm.go
diff --git a/contrib/go/_std_1.19/src/crypto/internal/edwards25519/field/fe_generic.go b/contrib/go/_std_1.19/src/crypto/internal/edwards25519/field/fe_generic.go
new file mode 100644
index 0000000000..d6667b27be
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/internal/edwards25519/field/fe_generic.go
@@ -0,0 +1,266 @@
+// Copyright (c) 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package field
+
+import "math/bits"
+
+// uint128 holds a 128-bit number as two 64-bit limbs, for use with the
+// bits.Mul64 and bits.Add64 intrinsics.
+type uint128 struct {
+	lo, hi uint64
+}
+
+// mul64 returns a * b.
+func mul64(a, b uint64) uint128 {
+	hi, lo := bits.Mul64(a, b)
+	return uint128{lo, hi}
+}
+
+// addMul64 returns v + a * b.
+func addMul64(v uint128, a, b uint64) uint128 {
+	hi, lo := bits.Mul64(a, b)
+	lo, c := bits.Add64(lo, v.lo, 0)
+	hi, _ = bits.Add64(hi, v.hi, c)
+	return uint128{lo, hi}
+}
+
+// shiftRightBy51 returns a >> 51. a is assumed to be at most 115 bits.
+func shiftRightBy51(a uint128) uint64 {
+	return (a.hi << (64 - 51)) | (a.lo >> 51)
+}
+
+func feMulGeneric(v, a, b *Element) {
+	a0 := a.l0
+	a1 := a.l1
+	a2 := a.l2
+	a3 := a.l3
+	a4 := a.l4
+
+	b0 := b.l0
+	b1 := b.l1
+	b2 := b.l2
+	b3 := b.l3
+	b4 := b.l4
+
+	// Limb multiplication works like pen-and-paper columnar multiplication, but
+	// with 51-bit limbs instead of digits.
+	//
+	//                          a4   a3   a2   a1   a0  x
+	//                          b4   b3   b2   b1   b0  =
+	//                         ------------------------
+	//                        a4b0 a3b0 a2b0 a1b0 a0b0  +
+	//                   a4b1 a3b1 a2b1 a1b1 a0b1       +
+	//              a4b2 a3b2 a2b2 a1b2 a0b2            +
+	//         a4b3 a3b3 a2b3 a1b3 a0b3                 +
+	//    a4b4 a3b4 a2b4 a1b4 a0b4                      =
+	//   ----------------------------------------------
+	//      r8   r7   r6   r5   r4   r3   r2   r1   r0
+	//
+	// We can then use the reduction identity (a * 2²⁵⁵ + b = a * 19 + b) to
+	// reduce the limbs that would overflow 255 bits. r5 * 2²⁵⁵ becomes 19 * r5,
+	// r6 * 2³⁰⁶ becomes 19 * r6 * 2⁵¹, etc.
+	//
+	// Reduction can be carried out simultaneously to multiplication. For
+	// example, we do not compute r5: whenever the result of a multiplication
+	// belongs to r5, like a1b4, we multiply it by 19 and add the result to r0.
+	//
+	//            a4b0    a3b0    a2b0    a1b0    a0b0  +
+	//            a3b1    a2b1    a1b1    a0b1 19×a4b1  +
+	//            a2b2    a1b2    a0b2 19×a4b2 19×a3b2  +
+	//            a1b3    a0b3 19×a4b3 19×a3b3 19×a2b3  +
+	//            a0b4 19×a4b4 19×a3b4 19×a2b4 19×a1b4  =
+	//           --------------------------------------
+	//              r4      r3      r2      r1      r0
+	//
+	// Finally we add up the columns into wide, overlapping limbs.
+
+	a1_19 := a1 * 19
+	a2_19 := a2 * 19
+	a3_19 := a3 * 19
+	a4_19 := a4 * 19
+
+	// r0 = a0×b0 + 19×(a1×b4 + a2×b3 + a3×b2 + a4×b1)
+	r0 := mul64(a0, b0)
+	r0 = addMul64(r0, a1_19, b4)
+	r0 = addMul64(r0, a2_19, b3)
+	r0 = addMul64(r0, a3_19, b2)
+	r0 = addMul64(r0, a4_19, b1)
+
+	// r1 = a0×b1 + a1×b0 + 19×(a2×b4 + a3×b3 + a4×b2)
+	r1 := mul64(a0, b1)
+	r1 = addMul64(r1, a1, b0)
+	r1 = addMul64(r1, a2_19, b4)
+	r1 = addMul64(r1, a3_19, b3)
+	r1 = addMul64(r1, a4_19, b2)
+
+	// r2 = a0×b2 + a1×b1 + a2×b0 + 19×(a3×b4 + a4×b3)
+	r2 := mul64(a0, b2)
+	r2 = addMul64(r2, a1, b1)
+	r2 = addMul64(r2, a2, b0)
+	r2 = addMul64(r2, a3_19, b4)
+	r2 = addMul64(r2, a4_19, b3)
+
+	// r3 = a0×b3 + a1×b2 + a2×b1 + a3×b0 + 19×a4×b4
+	r3 := mul64(a0, b3)
+	r3 = addMul64(r3, a1, b2)
+	r3 = addMul64(r3, a2, b1)
+	r3 = addMul64(r3, a3, b0)
+	r3 = addMul64(r3, a4_19, b4)
+
+	// r4 = a0×b4 + a1×b3 + a2×b2 + a3×b1 + a4×b0
+	r4 := mul64(a0, b4)
+	r4 = addMul64(r4, a1, b3)
+	r4 = addMul64(r4, a2, b2)
+	r4 = addMul64(r4, a3, b1)
+	r4 = addMul64(r4, a4, b0)
+
+	// After the multiplication, we need to reduce (carry) the five coefficients
+	// to obtain a result with limbs that are at most slightly larger than 2⁵¹,
+	// to respect the Element invariant.
+	//
+	// Overall, the reduction works the same as carryPropagate, except with
+	// wider inputs: we take the carry for each coefficient by shifting it right
+	// by 51, and add it to the limb above it. The top carry is multiplied by 19
+	// according to the reduction identity and added to the lowest limb.
+	//
+	// The largest coefficient (r0) will be at most 111 bits, which guarantees
+	// that all carries are at most 111 - 51 = 60 bits, which fits in a uint64.
+	//
+	//     r0 = a0×b0 + 19×(a1×b4 + a2×b3 + a3×b2 + a4×b1)
+	//     r0 < 2⁵²×2⁵² + 19×(2⁵²×2⁵² + 2⁵²×2⁵² + 2⁵²×2⁵² + 2⁵²×2⁵²)
+	//     r0 < (1 + 19 × 4) × 2⁵² × 2⁵²
+	//     r0 < 2⁷ × 2⁵² × 2⁵²
+	//     r0 < 2¹¹¹
+	//
+	// Moreover, the top coefficient (r4) is at most 107 bits, so c4 is at most
+	// 56 bits, and c4 * 19 is at most 61 bits, which again fits in a uint64 and
+	// allows us to easily apply the reduction identity.
+	//
+	//     r4 = a0×b4 + a1×b3 + a2×b2 + a3×b1 + a4×b0
+	//     r4 < 5 × 2⁵² × 2⁵²
+	//     r4 < 2¹⁰⁷
+	//
+
+	c0 := shiftRightBy51(r0)
+	c1 := shiftRightBy51(r1)
+	c2 := shiftRightBy51(r2)
+	c3 := shiftRightBy51(r3)
+	c4 := shiftRightBy51(r4)
+
+	rr0 := r0.lo&maskLow51Bits + c4*19
+	rr1 := r1.lo&maskLow51Bits + c0
+	rr2 := r2.lo&maskLow51Bits + c1
+	rr3 := r3.lo&maskLow51Bits + c2
+	rr4 := r4.lo&maskLow51Bits + c3
+
+	// Now all coefficients fit into 64-bit registers but are still too large to
+	// be passed around as a Element. We therefore do one last carry chain,
+	// where the carries will be small enough to fit in the wiggle room above 2⁵¹.
+	*v = Element{rr0, rr1, rr2, rr3, rr4}
+	v.carryPropagate()
+}
+
+func feSquareGeneric(v, a *Element) {
+	l0 := a.l0
+	l1 := a.l1
+	l2 := a.l2
+	l3 := a.l3
+	l4 := a.l4
+
+	// Squaring works precisely like multiplication above, but thanks to its
+	// symmetry we get to group a few terms together.
+	//
+	//                          l4   l3   l2   l1   l0  x
+	//                          l4   l3   l2   l1   l0  =
+	//                         ------------------------
+	//                        l4l0 l3l0 l2l0 l1l0 l0l0  +
+	//                   l4l1 l3l1 l2l1 l1l1 l0l1       +
+	//              l4l2 l3l2 l2l2 l1l2 l0l2            +
+	//         l4l3 l3l3 l2l3 l1l3 l0l3                 +
+	//    l4l4 l3l4 l2l4 l1l4 l0l4                      =
+	//   ----------------------------------------------
+	//      r8   r7   r6   r5   r4   r3   r2   r1   r0
+	//
+	//            l4l0    l3l0    l2l0    l1l0    l0l0  +
+	//            l3l1    l2l1    l1l1    l0l1 19×l4l1  +
+	//            l2l2    l1l2    l0l2 19×l4l2 19×l3l2  +
+	//            l1l3    l0l3 19×l4l3 19×l3l3 19×l2l3  +
+	//            l0l4 19×l4l4 19×l3l4 19×l2l4 19×l1l4  =
+	//           --------------------------------------
+	//              r4      r3      r2      r1      r0
+	//
+	// With precomputed 2×, 19×, and 2×19× terms, we can compute each limb with
+	// only three Mul64 and four Add64, instead of five and eight.
+
+	l0_2 := l0 * 2
+	l1_2 := l1 * 2
+
+	l1_38 := l1 * 38
+	l2_38 := l2 * 38
+	l3_38 := l3 * 38
+
+	l3_19 := l3 * 19
+	l4_19 := l4 * 19
+
+	// r0 = l0×l0 + 19×(l1×l4 + l2×l3 + l3×l2 + l4×l1) = l0×l0 + 19×2×(l1×l4 + l2×l3)
+	r0 := mul64(l0, l0)
+	r0 = addMul64(r0, l1_38, l4)
+	r0 = addMul64(r0, l2_38, l3)
+
+	// r1 = l0×l1 + l1×l0 + 19×(l2×l4 + l3×l3 + l4×l2) = 2×l0×l1 + 19×2×l2×l4 + 19×l3×l3
+	r1 := mul64(l0_2, l1)
+	r1 = addMul64(r1, l2_38, l4)
+	r1 = addMul64(r1, l3_19, l3)
+
+	// r2 = l0×l2 + l1×l1 + l2×l0 + 19×(l3×l4 + l4×l3) = 2×l0×l2 + l1×l1 + 19×2×l3×l4
+	r2 := mul64(l0_2, l2)
+	r2 = addMul64(r2, l1, l1)
+	r2 = addMul64(r2, l3_38, l4)
+
+	// r3 = l0×l3 + l1×l2 + l2×l1 + l3×l0 + 19×l4×l4 = 2×l0×l3 + 2×l1×l2 + 19×l4×l4
+	r3 := mul64(l0_2, l3)
+	r3 = addMul64(r3, l1_2, l2)
+	r3 = addMul64(r3, l4_19, l4)
+
+	// r4 = l0×l4 + l1×l3 + l2×l2 + l3×l1 + l4×l0 = 2×l0×l4 + 2×l1×l3 + l2×l2
+	r4 := mul64(l0_2, l4)
+	r4 = addMul64(r4, l1_2, l3)
+	r4 = addMul64(r4, l2, l2)
+
+	c0 := shiftRightBy51(r0)
+	c1 := shiftRightBy51(r1)
+	c2 := shiftRightBy51(r2)
+	c3 := shiftRightBy51(r3)
+	c4 := shiftRightBy51(r4)
+
+	rr0 := r0.lo&maskLow51Bits + c4*19
+	rr1 := r1.lo&maskLow51Bits + c0
+	rr2 := r2.lo&maskLow51Bits + c1
+	rr3 := r3.lo&maskLow51Bits + c2
+	rr4 := r4.lo&maskLow51Bits + c3
+
+	*v = Element{rr0, rr1, rr2, rr3, rr4}
+	v.carryPropagate()
+}
+
+// carryPropagate brings the limbs below 52 bits by applying the reduction
+// identity (a * 2²⁵⁵ + b = a * 19 + b) to the l4 carry.
+func (v *Element) carryPropagateGeneric() *Element {
+	c0 := v.l0 >> 51
+	c1 := v.l1 >> 51
+	c2 := v.l2 >> 51
+	c3 := v.l3 >> 51
+	c4 := v.l4 >> 51
+
+	// c4 is at most 64 - 51 = 13 bits, so c4*19 is at most 18 bits, and
+	// the final l0 will be at most 52 bits. Similarly for the rest.
+	v.l0 = v.l0&maskLow51Bits + c4*19
+	v.l1 = v.l1&maskLow51Bits + c0
+	v.l2 = v.l2&maskLow51Bits + c1
+	v.l3 = v.l3&maskLow51Bits + c2
+	v.l4 = v.l4&maskLow51Bits + c3
+
+	return v
+}
diff --git a/contrib/go/_std_1.19/src/crypto/internal/edwards25519/scalar.go b/contrib/go/_std_1.19/src/crypto/internal/edwards25519/scalar.go
new file mode 100644
index 0000000000..4530bc3ce2
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/internal/edwards25519/scalar.go
@@ -0,0 +1,1034 @@
+// Copyright (c) 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package edwards25519
+
+import (
+	"crypto/subtle"
+	"encoding/binary"
+	"errors"
+)
+
+// A Scalar is an integer modulo
+//
+//	l = 2^252 + 27742317777372353535851937790883648493
+//
+// which is the prime order of the edwards25519 group.
+//
+// This type works similarly to math/big.Int, and all arguments and
+// receivers are allowed to alias.
+//
+// The zero value is a valid zero element.
+type Scalar struct {
+	// s is the Scalar value in little-endian. The value is always reduced
+	// modulo l between operations.
+	s [32]byte
+}
+
+var (
+	scZero = Scalar{[32]byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}}
+
+	scOne = Scalar{[32]byte{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}}
+
+	scMinusOne = Scalar{[32]byte{236, 211, 245, 92, 26, 99, 18, 88, 214, 156, 247, 162, 222, 249, 222, 20, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 16}}
+)
+
+// NewScalar returns a new zero Scalar.
+func NewScalar() *Scalar {
+	return &Scalar{}
+}
+
+// MultiplyAdd sets s = x * y + z mod l, and returns s.
+func (s *Scalar) MultiplyAdd(x, y, z *Scalar) *Scalar {
+	scMulAdd(&s.s, &x.s, &y.s, &z.s)
+	return s
+}
+
+// Add sets s = x + y mod l, and returns s.
+func (s *Scalar) Add(x, y *Scalar) *Scalar {
+	// s = 1 * x + y mod l
+	scMulAdd(&s.s, &scOne.s, &x.s, &y.s)
+	return s
+}
+
+// Subtract sets s = x - y mod l, and returns s.
+func (s *Scalar) Subtract(x, y *Scalar) *Scalar {
+	// s = -1 * y + x mod l
+	scMulAdd(&s.s, &scMinusOne.s, &y.s, &x.s)
+	return s
+}
+
+// Negate sets s = -x mod l, and returns s.
+func (s *Scalar) Negate(x *Scalar) *Scalar {
+	// s = -1 * x + 0 mod l
+	scMulAdd(&s.s, &scMinusOne.s, &x.s, &scZero.s)
+	return s
+}
+
+// Multiply sets s = x * y mod l, and returns s.
+func (s *Scalar) Multiply(x, y *Scalar) *Scalar {
+	// s = x * y + 0 mod l
+	scMulAdd(&s.s, &x.s, &y.s, &scZero.s)
+	return s
+}
+
+// Set sets s = x, and returns s.
+func (s *Scalar) Set(x *Scalar) *Scalar {
+	*s = *x
+	return s
+}
+
+// SetUniformBytes sets s = x mod l, where x is a 64-byte little-endian integer.
+// If x is not of the right length, SetUniformBytes returns nil and an error,
+// and the receiver is unchanged.
+//
+// SetUniformBytes can be used to set s to an uniformly distributed value given
+// 64 uniformly distributed random bytes.
+func (s *Scalar) SetUniformBytes(x []byte) (*Scalar, error) {
+	if len(x) != 64 {
+		return nil, errors.New("edwards25519: invalid SetUniformBytes input length")
+	}
+	var wideBytes [64]byte
+	copy(wideBytes[:], x[:])
+	scReduce(&s.s, &wideBytes)
+	return s, nil
+}
+
+// SetCanonicalBytes sets s = x, where x is a 32-byte little-endian encoding of
+// s, and returns s. If x is not a canonical encoding of s, SetCanonicalBytes
+// returns nil and an error, and the receiver is unchanged.
+func (s *Scalar) SetCanonicalBytes(x []byte) (*Scalar, error) {
+	if len(x) != 32 {
+		return nil, errors.New("invalid scalar length")
+	}
+	ss := &Scalar{}
+	copy(ss.s[:], x)
+	if !isReduced(ss) {
+		return nil, errors.New("invalid scalar encoding")
+	}
+	s.s = ss.s
+	return s, nil
+}
+
+// isReduced returns whether the given scalar is reduced modulo l.
+func isReduced(s *Scalar) bool {
+	for i := len(s.s) - 1; i >= 0; i-- {
+		switch {
+		case s.s[i] > scMinusOne.s[i]:
+			return false
+		case s.s[i] < scMinusOne.s[i]:
+			return true
+		}
+	}
+	return true
+}
+
+// SetBytesWithClamping applies the buffer pruning described in RFC 8032,
+// Section 5.1.5 (also known as clamping) and sets s to the result. The input
+// must be 32 bytes, and it is not modified. If x is not of the right length,
+// SetBytesWithClamping returns nil and an error, and the receiver is unchanged.
+//
+// Note that since Scalar values are always reduced modulo the prime order of
+// the curve, the resulting value will not preserve any of the cofactor-clearing
+// properties that clamping is meant to provide. It will however work as
+// expected as long as it is applied to points on the prime order subgroup, like
+// in Ed25519. In fact, it is lost to history why RFC 8032 adopted the
+// irrelevant RFC 7748 clamping, but it is now required for compatibility.
+func (s *Scalar) SetBytesWithClamping(x []byte) (*Scalar, error) {
+	// The description above omits the purpose of the high bits of the clamping
+	// for brevity, but those are also lost to reductions, and are also
+	// irrelevant to edwards25519 as they protect against a specific
+	// implementation bug that was once observed in a generic Montgomery ladder.
+	if len(x) != 32 {
+		return nil, errors.New("edwards25519: invalid SetBytesWithClamping input length")
+	}
+	var wideBytes [64]byte
+	copy(wideBytes[:], x[:])
+	wideBytes[0] &= 248
+	wideBytes[31] &= 63
+	wideBytes[31] |= 64
+	scReduce(&s.s, &wideBytes)
+	return s, nil
+}
+
+// Bytes returns the canonical 32-byte little-endian encoding of s.
+func (s *Scalar) Bytes() []byte {
+	buf := make([]byte, 32)
+	copy(buf, s.s[:])
+	return buf
+}
+
+// Equal returns 1 if s and t are equal, and 0 otherwise.
+func (s *Scalar) Equal(t *Scalar) int {
+	return subtle.ConstantTimeCompare(s.s[:], t.s[:])
+}
+
+// scMulAdd and scReduce are ported from the public domain, “ref10”
+// implementation of ed25519 from SUPERCOP.
+
+func load3(in []byte) int64 {
+	r := int64(in[0])
+	r |= int64(in[1]) << 8
+	r |= int64(in[2]) << 16
+	return r
+}
+
+func load4(in []byte) int64 {
+	r := int64(in[0])
+	r |= int64(in[1]) << 8
+	r |= int64(in[2]) << 16
+	r |= int64(in[3]) << 24
+	return r
+}
+
+// Input:
+//
+//	a[0]+256*a[1]+...+256^31*a[31] = a
+//	b[0]+256*b[1]+...+256^31*b[31] = b
+//	c[0]+256*c[1]+...+256^31*c[31] = c
+//
+// Output:
+//
+//	s[0]+256*s[1]+...+256^31*s[31] = (ab+c) mod l
+//	where l = 2^252 + 27742317777372353535851937790883648493.
+func scMulAdd(s, a, b, c *[32]byte) {
+	a0 := 2097151 & load3(a[:])
+	a1 := 2097151 & (load4(a[2:]) >> 5)
+	a2 := 2097151 & (load3(a[5:]) >> 2)
+	a3 := 2097151 & (load4(a[7:]) >> 7)
+	a4 := 2097151 & (load4(a[10:]) >> 4)
+	a5 := 2097151 & (load3(a[13:]) >> 1)
+	a6 := 2097151 & (load4(a[15:]) >> 6)
+	a7 := 2097151 & (load3(a[18:]) >> 3)
+	a8 := 2097151 & load3(a[21:])
+	a9 := 2097151 & (load4(a[23:]) >> 5)
+	a10 := 2097151 & (load3(a[26:]) >> 2)
+	a11 := (load4(a[28:]) >> 7)
+	b0 := 2097151 & load3(b[:])
+	b1 := 2097151 & (load4(b[2:]) >> 5)
+	b2 := 2097151 & (load3(b[5:]) >> 2)
+	b3 := 2097151 & (load4(b[7:]) >> 7)
+	b4 := 2097151 & (load4(b[10:]) >> 4)
+	b5 := 2097151 & (load3(b[13:]) >> 1)
+	b6 := 2097151 & (load4(b[15:]) >> 6)
+	b7 := 2097151 & (load3(b[18:]) >> 3)
+	b8 := 2097151 & load3(b[21:])
+	b9 := 2097151 & (load4(b[23:]) >> 5)
+	b10 := 2097151 & (load3(b[26:]) >> 2)
+	b11 := (load4(b[28:]) >> 7)
+	c0 := 2097151 & load3(c[:])
+	c1 := 2097151 & (load4(c[2:]) >> 5)
+	c2 := 2097151 & (load3(c[5:]) >> 2)
+	c3 := 2097151 & (load4(c[7:]) >> 7)
+	c4 := 2097151 & (load4(c[10:]) >> 4)
+	c5 := 2097151 & (load3(c[13:]) >> 1)
+	c6 := 2097151 & (load4(c[15:]) >> 6)
+	c7 := 2097151 & (load3(c[18:]) >> 3)
+	c8 := 2097151 & load3(c[21:])
+	c9 := 2097151 & (load4(c[23:]) >> 5)
+	c10 := 2097151 & (load3(c[26:]) >> 2)
+	c11 := (load4(c[28:]) >> 7)
+	var carry [23]int64
+
+	s0 := c0 + a0*b0
+	s1 := c1 + a0*b1 + a1*b0
+	s2 := c2 + a0*b2 + a1*b1 + a2*b0
+	s3 := c3 + a0*b3 + a1*b2 + a2*b1 + a3*b0
+	s4 := c4 + a0*b4 + a1*b3 + a2*b2 + a3*b1 + a4*b0
+	s5 := c5 + a0*b5 + a1*b4 + a2*b3 + a3*b2 + a4*b1 + a5*b0
+	s6 := c6 + a0*b6 + a1*b5 + a2*b4 + a3*b3 + a4*b2 + a5*b1 + a6*b0
+	s7 := c7 + a0*b7 + a1*b6 + a2*b5 + a3*b4 + a4*b3 + a5*b2 + a6*b1 + a7*b0
+	s8 := c8 + a0*b8 + a1*b7 + a2*b6 + a3*b5 + a4*b4 + a5*b3 + a6*b2 + a7*b1 + a8*b0
+	s9 := c9 + a0*b9 + a1*b8 + a2*b7 + a3*b6 + a4*b5 + a5*b4 + a6*b3 + a7*b2 + a8*b1 + a9*b0
+	s10 := c10 + a0*b10 + a1*b9 + a2*b8 + a3*b7 + a4*b6 + a5*b5 + a6*b4 + a7*b3 + a8*b2 + a9*b1 + a10*b0
+	s11 := c11 + a0*b11 + a1*b10 + a2*b9 + a3*b8 + a4*b7 + a5*b6 + a6*b5 + a7*b4 + a8*b3 + a9*b2 + a10*b1 + a11*b0
+	s12 := a1*b11 + a2*b10 + a3*b9 + a4*b8 + a5*b7 + a6*b6 + a7*b5 + a8*b4 + a9*b3 + a10*b2 + a11*b1
+	s13 := a2*b11 + a3*b10 + a4*b9 + a5*b8 + a6*b7 + a7*b6 + a8*b5 + a9*b4 + a10*b3 + a11*b2
+	s14 := a3*b11 + a4*b10 + a5*b9 + a6*b8 + a7*b7 + a8*b6 + a9*b5 + a10*b4 + a11*b3
+	s15 := a4*b11 + a5*b10 + a6*b9 + a7*b8 + a8*b7 + a9*b6 + a10*b5 + a11*b4
+	s16 := a5*b11 + a6*b10 + a7*b9 + a8*b8 + a9*b7 + a10*b6 + a11*b5
+	s17 := a6*b11 + a7*b10 + a8*b9 + a9*b8 + a10*b7 + a11*b6
+	s18 := a7*b11 + a8*b10 + a9*b9 + a10*b8 + a11*b7
+	s19 := a8*b11 + a9*b10 + a10*b9 + a11*b8
+	s20 := a9*b11 + a10*b10 + a11*b9
+	s21 := a10*b11 + a11*b10
+	s22 := a11 * b11
+	s23 := int64(0)
+
+	carry[0] = (s0 + (1 << 20)) >> 21
+	s1 += carry[0]
+	s0 -= carry[0] << 21
+	carry[2] = (s2 + (1 << 20)) >> 21
+	s3 += carry[2]
+	s2 -= carry[2] << 21
+	carry[4] = (s4 + (1 << 20)) >> 21
+	s5 += carry[4]
+	s4 -= carry[4] << 21
+	carry[6] = (s6 + (1 << 20)) >> 21
+	s7 += carry[6]
+	s6 -= carry[6] << 21
+	carry[8] = (s8 + (1 << 20)) >> 21
+	s9 += carry[8]
+	s8 -= carry[8] << 21
+	carry[10] = (s10 + (1 << 20)) >> 21
+	s11 += carry[10]
+	s10 -= carry[10] << 21
+	carry[12] = (s12 + (1 << 20)) >> 21
+	s13 += carry[12]
+	s12 -= carry[12] << 21
+	carry[14] = (s14 + (1 << 20)) >> 21
+	s15 += carry[14]
+	s14 -= carry[14] << 21
+	carry[16] = (s16 + (1 << 20)) >> 21
+	s17 += carry[16]
+	s16 -= carry[16] << 21
+	carry[18] = (s18 + (1 << 20)) >> 21
+	s19 += carry[18]
+	s18 -= carry[18] << 21
+	carry[20] = (s20 + (1 << 20)) >> 21
+	s21 += carry[20]
+	s20 -= carry[20] << 21
+	carry[22] = (s22 + (1 << 20)) >> 21
+	s23 += carry[22]
+	s22 -= carry[22] << 21
+
+	carry[1] = (s1 + (1 << 20)) >> 21
+	s2 += carry[1]
+	s1 -= carry[1] << 21
+	carry[3] = (s3 + (1 << 20)) >> 21
+	s4 += carry[3]
+	s3 -= carry[3] << 21
+	carry[5] = (s5 + (1 << 20)) >> 21
+	s6 += carry[5]
+	s5 -= carry[5] << 21
+	carry[7] = (s7 + (1 << 20)) >> 21
+	s8 += carry[7]
+	s7 -= carry[7] << 21
+	carry[9] = (s9 + (1 << 20)) >> 21
+	s10 += carry[9]
+	s9 -= carry[9] << 21
+	carry[11] = (s11 + (1 << 20)) >> 21
+	s12 += carry[11]
+	s11 -= carry[11] << 21
+	carry[13] = (s13 + (1 << 20)) >> 21
+	s14 += carry[13]
+	s13 -= carry[13] << 21
+	carry[15] = (s15 + (1 << 20)) >> 21
+	s16 += carry[15]
+	s15 -= carry[15] << 21
+	carry[17] = (s17 + (1 << 20)) >> 21
+	s18 += carry[17]
+	s17 -= carry[17] << 21
+	carry[19] = (s19 + (1 << 20)) >> 21
+	s20 += carry[19]
+	s19 -= carry[19] << 21
+	carry[21] = (s21 + (1 << 20)) >> 21
+	s22 += carry[21]
+	s21 -= carry[21] << 21
+
+	s11 += s23 * 666643
+	s12 += s23 * 470296
+	s13 += s23 * 654183
+	s14 -= s23 * 997805
+	s15 += s23 * 136657
+	s16 -= s23 * 683901
+	s23 = 0
+
+	s10 += s22 * 666643
+	s11 += s22 * 470296
+	s12 += s22 * 654183
+	s13 -= s22 * 997805
+	s14 += s22 * 136657
+	s15 -= s22 * 683901
+	s22 = 0
+
+	s9 += s21 * 666643
+	s10 += s21 * 470296
+	s11 += s21 * 654183
+	s12 -= s21 * 997805
+	s13 += s21 * 136657
+	s14 -= s21 * 683901
+	s21 = 0
+
+	s8 += s20 * 666643
+	s9 += s20 * 470296
+	s10 += s20 * 654183
+	s11 -= s20 * 997805
+	s12 += s20 * 136657
+	s13 -= s20 * 683901
+	s20 = 0
+
+	s7 += s19 * 666643
+	s8 += s19 * 470296
+	s9 += s19 * 654183
+	s10 -= s19 * 997805
+	s11 += s19 * 136657
+	s12 -= s19 * 683901
+	s19 = 0
+
+	s6 += s18 * 666643
+	s7 += s18 * 470296
+	s8 += s18 * 654183
+	s9 -= s18 * 997805
+	s10 += s18 * 136657
+	s11 -= s18 * 683901
+	s18 = 0
+
+	carry[6] = (s6 + (1 << 20)) >> 21
+	s7 += carry[6]
+	s6 -= carry[6] << 21
+	carry[8] = (s8 + (1 << 20)) >> 21
+	s9 += carry[8]
+	s8 -= carry[8] << 21
+	carry[10] = (s10 + (1 << 20)) >> 21
+	s11 += carry[10]
+	s10 -= carry[10] << 21
+	carry[12] = (s12 + (1 << 20)) >> 21
+	s13 += carry[12]
+	s12 -= carry[12] << 21
+	carry[14] = (s14 + (1 << 20)) >> 21
+	s15 += carry[14]
+	s14 -= carry[14] << 21
+	carry[16] = (s16 + (1 << 20)) >> 21
+	s17 += carry[16]
+	s16 -= carry[16] << 21
+
+	carry[7] = (s7 + (1 << 20)) >> 21
+	s8 += carry[7]
+	s7 -= carry[7] << 21
+	carry[9] = (s9 + (1 << 20)) >> 21
+	s10 += carry[9]
+	s9 -= carry[9] << 21
+	carry[11] = (s11 + (1 << 20)) >> 21
+	s12 += carry[11]
+	s11 -= carry[11] << 21
+	carry[13] = (s13 + (1 << 20)) >> 21
+	s14 += carry[13]
+	s13 -= carry[13] << 21
+	carry[15] = (s15 + (1 << 20)) >> 21
+	s16 += carry[15]
+	s15 -= carry[15] << 21
+
+	s5 += s17 * 666643
+	s6 += s17 * 470296
+	s7 += s17 * 654183
+	s8 -= s17 * 997805
+	s9 += s17 * 136657
+	s10 -= s17 * 683901
+	s17 = 0
+
+	s4 += s16 * 666643
+	s5 += s16 * 470296
+	s6 += s16 * 654183
+	s7 -= s16 * 997805
+	s8 += s16 * 136657
+	s9 -= s16 * 683901
+	s16 = 0
+
+	s3 += s15 * 666643
+	s4 += s15 * 470296
+	s5 += s15 * 654183
+	s6 -= s15 * 997805
+	s7 += s15 * 136657
+	s8 -= s15 * 683901
+	s15 = 0
+
+	s2 += s14 * 666643
+	s3 += s14 * 470296
+	s4 += s14 * 654183
+	s5 -= s14 * 997805
+	s6 += s14 * 136657
+	s7 -= s14 * 683901
+	s14 = 0
+
+	s1 += s13 * 666643
+	s2 += s13 * 470296
+	s3 += s13 * 654183
+	s4 -= s13 * 997805
+	s5 += s13 * 136657
+	s6 -= s13 * 683901
+	s13 = 0
+
+	s0 += s12 * 666643
+	s1 += s12 * 470296
+	s2 += s12 * 654183
+	s3 -= s12 * 997805
+	s4 += s12 * 136657
+	s5 -= s12 * 683901
+	s12 = 0
+
+	carry[0] = (s0 + (1 << 20)) >> 21
+	s1 += carry[0]
+	s0 -= carry[0] << 21
+	carry[2] = (s2 + (1 << 20)) >> 21
+	s3 += carry[2]
+	s2 -= carry[2] << 21
+	carry[4] = (s4 + (1 << 20)) >> 21
+	s5 += carry[4]
+	s4 -= carry[4] << 21
+	carry[6] = (s6 + (1 << 20)) >> 21
+	s7 += carry[6]
+	s6 -= carry[6] << 21
+	carry[8] = (s8 + (1 << 20)) >> 21
+	s9 += carry[8]
+	s8 -= carry[8] << 21
+	carry[10] = (s10 + (1 << 20)) >> 21
+	s11 += carry[10]
+	s10 -= carry[10] << 21
+
+	carry[1] = (s1 + (1 << 20)) >> 21
+	s2 += carry[1]
+	s1 -= carry[1] << 21
+	carry[3] = (s3 + (1 << 20)) >> 21
+	s4 += carry[3]
+	s3 -= carry[3] << 21
+	carry[5] = (s5 + (1 << 20)) >> 21
+	s6 += carry[5]
+	s5 -= carry[5] << 21
+	carry[7] = (s7 + (1 << 20)) >> 21
+	s8 += carry[7]
+	s7 -= carry[7] << 21
+	carry[9] = (s9 + (1 << 20)) >> 21
+	s10 += carry[9]
+	s9 -= carry[9] << 21
+	carry[11] = (s11 + (1 << 20)) >> 21
+	s12 += carry[11]
+	s11 -= carry[11] << 21
+
+	s0 += s12 * 666643
+	s1 += s12 * 470296
+	s2 += s12 * 654183
+	s3 -= s12 * 997805
+	s4 += s12 * 136657
+	s5 -= s12 * 683901
+	s12 = 0
+
+	carry[0] = s0 >> 21
+	s1 += carry[0]
+	s0 -= carry[0] << 21
+	carry[1] = s1 >> 21
+	s2 += carry[1]
+	s1 -= carry[1] << 21
+	carry[2] = s2 >> 21
+	s3 += carry[2]
+	s2 -= carry[2] << 21
+	carry[3] = s3 >> 21
+	s4 += carry[3]
+	s3 -= carry[3] << 21
+	carry[4] = s4 >> 21
+	s5 += carry[4]
+	s4 -= carry[4] << 21
+	carry[5] = s5 >> 21
+	s6 += carry[5]
+	s5 -= carry[5] << 21
+	carry[6] = s6 >> 21
+	s7 += carry[6]
+	s6 -= carry[6] << 21
+	carry[7] = s7 >> 21
+	s8 += carry[7]
+	s7 -= carry[7] << 21
+	carry[8] = s8 >> 21
+	s9 += carry[8]
+	s8 -= carry[8] << 21
+	carry[9] = s9 >> 21
+	s10 += carry[9]
+	s9 -= carry[9] << 21
+	carry[10] = s10 >> 21
+	s11 += carry[10]
+	s10 -= carry[10] << 21
+	carry[11] = s11 >> 21
+	s12 += carry[11]
+	s11 -= carry[11] << 21
+
+	s0 += s12 * 666643
+	s1 += s12 * 470296
+	s2 += s12 * 654183
+	s3 -= s12 * 997805
+	s4 += s12 * 136657
+	s5 -= s12 * 683901
+	s12 = 0
+
+	carry[0] = s0 >> 21
+	s1 += carry[0]
+	s0 -= carry[0] << 21
+	carry[1] = s1 >> 21
+	s2 += carry[1]
+	s1 -= carry[1] << 21
+	carry[2] = s2 >> 21
+	s3 += carry[2]
+	s2 -= carry[2] << 21
+	carry[3] = s3 >> 21
+	s4 += carry[3]
+	s3 -= carry[3] << 21
+	carry[4] = s4 >> 21
+	s5 += carry[4]
+	s4 -= carry[4] << 21
+	carry[5] = s5 >> 21
+	s6 += carry[5]
+	s5 -= carry[5] << 21
+	carry[6] = s6 >> 21
+	s7 += carry[6]
+	s6 -= carry[6] << 21
+	carry[7] = s7 >> 21
+	s8 += carry[7]
+	s7 -= carry[7] << 21
+	carry[8] = s8 >> 21
+	s9 += carry[8]
+	s8 -= carry[8] << 21
+	carry[9] = s9 >> 21
+	s10 += carry[9]
+	s9 -= carry[9] << 21
+	carry[10] = s10 >> 21
+	s11 += carry[10]
+	s10 -= carry[10] << 21
+
+	s[0] = byte(s0 >> 0)
+	s[1] = byte(s0 >> 8)
+	s[2] = byte((s0 >> 16) | (s1 << 5))
+	s[3] = byte(s1 >> 3)
+	s[4] = byte(s1 >> 11)
+	s[5] = byte((s1 >> 19) | (s2 << 2))
+	s[6] = byte(s2 >> 6)
+	s[7] = byte((s2 >> 14) | (s3 << 7))
+	s[8] = byte(s3 >> 1)
+	s[9] = byte(s3 >> 9)
+	s[10] = byte((s3 >> 17) | (s4 << 4))
+	s[11] = byte(s4 >> 4)
+	s[12] = byte(s4 >> 12)
+	s[13] = byte((s4 >> 20) | (s5 << 1))
+	s[14] = byte(s5 >> 7)
+	s[15] = byte((s5 >> 15) | (s6 << 6))
+	s[16] = byte(s6 >> 2)
+	s[17] = byte(s6 >> 10)
+	s[18] = byte((s6 >> 18) | (s7 << 3))
+	s[19] = byte(s7 >> 5)
+	s[20] = byte(s7 >> 13)
+	s[21] = byte(s8 >> 0)
+	s[22] = byte(s8 >> 8)
+	s[23] = byte((s8 >> 16) | (s9 << 5))
+	s[24] = byte(s9 >> 3)
+	s[25] = byte(s9 >> 11)
+	s[26] = byte((s9 >> 19) | (s10 << 2))
+	s[27] = byte(s10 >> 6)
+	s[28] = byte((s10 >> 14) | (s11 << 7))
+	s[29] = byte(s11 >> 1)
+	s[30] = byte(s11 >> 9)
+	s[31] = byte(s11 >> 17)
+}
+
+// Input:
+//
+//	s[0]+256*s[1]+...+256^63*s[63] = s
+//
+// Output:
+//
+//	s[0]+256*s[1]+...+256^31*s[31] = s mod l
+//	where l = 2^252 + 27742317777372353535851937790883648493.
+func scReduce(out *[32]byte, s *[64]byte) {
+	s0 := 2097151 & load3(s[:])
+	s1 := 2097151 & (load4(s[2:]) >> 5)
+	s2 := 2097151 & (load3(s[5:]) >> 2)
+	s3 := 2097151 & (load4(s[7:]) >> 7)
+	s4 := 2097151 & (load4(s[10:]) >> 4)
+	s5 := 2097151 & (load3(s[13:]) >> 1)
+	s6 := 2097151 & (load4(s[15:]) >> 6)
+	s7 := 2097151 & (load3(s[18:]) >> 3)
+	s8 := 2097151 & load3(s[21:])
+	s9 := 2097151 & (load4(s[23:]) >> 5)
+	s10 := 2097151 & (load3(s[26:]) >> 2)
+	s11 := 2097151 & (load4(s[28:]) >> 7)
+	s12 := 2097151 & (load4(s[31:]) >> 4)
+	s13 := 2097151 & (load3(s[34:]) >> 1)
+	s14 := 2097151 & (load4(s[36:]) >> 6)
+	s15 := 2097151 & (load3(s[39:]) >> 3)
+	s16 := 2097151 & load3(s[42:])
+	s17 := 2097151 & (load4(s[44:]) >> 5)
+	s18 := 2097151 & (load3(s[47:]) >> 2)
+	s19 := 2097151 & (load4(s[49:]) >> 7)
+	s20 := 2097151 & (load4(s[52:]) >> 4)
+	s21 := 2097151 & (load3(s[55:]) >> 1)
+	s22 := 2097151 & (load4(s[57:]) >> 6)
+	s23 := (load4(s[60:]) >> 3)
+
+	s11 += s23 * 666643
+	s12 += s23 * 470296
+	s13 += s23 * 654183
+	s14 -= s23 * 997805
+	s15 += s23 * 136657
+	s16 -= s23 * 683901
+	s23 = 0
+
+	s10 += s22 * 666643
+	s11 += s22 * 470296
+	s12 += s22 * 654183
+	s13 -= s22 * 997805
+	s14 += s22 * 136657
+	s15 -= s22 * 683901
+	s22 = 0
+
+	s9 += s21 * 666643
+	s10 += s21 * 470296
+	s11 += s21 * 654183
+	s12 -= s21 * 997805
+	s13 += s21 * 136657
+	s14 -= s21 * 683901
+	s21 = 0
+
+	s8 += s20 * 666643
+	s9 += s20 * 470296
+	s10 += s20 * 654183
+	s11 -= s20 * 997805
+	s12 += s20 * 136657
+	s13 -= s20 * 683901
+	s20 = 0
+
+	s7 += s19 * 666643
+	s8 += s19 * 470296
+	s9 += s19 * 654183
+	s10 -= s19 * 997805
+	s11 += s19 * 136657
+	s12 -= s19 * 683901
+	s19 = 0
+
+	s6 += s18 * 666643
+	s7 += s18 * 470296
+	s8 += s18 * 654183
+	s9 -= s18 * 997805
+	s10 += s18 * 136657
+	s11 -= s18 * 683901
+	s18 = 0
+
+	var carry [17]int64
+
+	carry[6] = (s6 + (1 << 20)) >> 21
+	s7 += carry[6]
+	s6 -= carry[6] << 21
+	carry[8] = (s8 + (1 << 20)) >> 21
+	s9 += carry[8]
+	s8 -= carry[8] << 21
+	carry[10] = (s10 + (1 << 20)) >> 21
+	s11 += carry[10]
+	s10 -= carry[10] << 21
+	carry[12] = (s12 + (1 << 20)) >> 21
+	s13 += carry[12]
+	s12 -= carry[12] << 21
+	carry[14] = (s14 + (1 << 20)) >> 21
+	s15 += carry[14]
+	s14 -= carry[14] << 21
+	carry[16] = (s16 + (1 << 20)) >> 21
+	s17 += carry[16]
+	s16 -= carry[16] << 21
+
+	carry[7] = (s7 + (1 << 20)) >> 21
+	s8 += carry[7]
+	s7 -= carry[7] << 21
+	carry[9] = (s9 + (1 << 20)) >> 21
+	s10 += carry[9]
+	s9 -= carry[9] << 21
+	carry[11] = (s11 + (1 << 20)) >> 21
+	s12 += carry[11]
+	s11 -= carry[11] << 21
+	carry[13] = (s13 + (1 << 20)) >> 21
+	s14 += carry[13]
+	s13 -= carry[13] << 21
+	carry[15] = (s15 + (1 << 20)) >> 21
+	s16 += carry[15]
+	s15 -= carry[15] << 21
+
+	s5 += s17 * 666643
+	s6 += s17 * 470296
+	s7 += s17 * 654183
+	s8 -= s17 * 997805
+	s9 += s17 * 136657
+	s10 -= s17 * 683901
+	s17 = 0
+
+	s4 += s16 * 666643
+	s5 += s16 * 470296
+	s6 += s16 * 654183
+	s7 -= s16 * 997805
+	s8 += s16 * 136657
+	s9 -= s16 * 683901
+	s16 = 0
+
+	s3 += s15 * 666643
+	s4 += s15 * 470296
+	s5 += s15 * 654183
+	s6 -= s15 * 997805
+	s7 += s15 * 136657
+	s8 -= s15 * 683901
+	s15 = 0
+
+	s2 += s14 * 666643
+	s3 += s14 * 470296
+	s4 += s14 * 654183
+	s5 -= s14 * 997805
+	s6 += s14 * 136657
+	s7 -= s14 * 683901
+	s14 = 0
+
+	s1 += s13 * 666643
+	s2 += s13 * 470296
+	s3 += s13 * 654183
+	s4 -= s13 * 997805
+	s5 += s13 * 136657
+	s6 -= s13 * 683901
+	s13 = 0
+
+	s0 += s12 * 666643
+	s1 += s12 * 470296
+	s2 += s12 * 654183
+	s3 -= s12 * 997805
+	s4 += s12 * 136657
+	s5 -= s12 * 683901
+	s12 = 0
+
+	carry[0] = (s0 + (1 << 20)) >> 21
+	s1 += carry[0]
+	s0 -= carry[0] << 21
+	carry[2] = (s2 + (1 << 20)) >> 21
+	s3 += carry[2]
+	s2 -= carry[2] << 21
+	carry[4] = (s4 + (1 << 20)) >> 21
+	s5 += carry[4]
+	s4 -= carry[4] << 21
+	carry[6] = (s6 + (1 << 20)) >> 21
+	s7 += carry[6]
+	s6 -= carry[6] << 21
+	carry[8] = (s8 + (1 << 20)) >> 21
+	s9 += carry[8]
+	s8 -= carry[8] << 21
+	carry[10] = (s10 + (1 << 20)) >> 21
+	s11 += carry[10]
+	s10 -= carry[10] << 21
+
+	carry[1] = (s1 + (1 << 20)) >> 21
+	s2 += carry[1]
+	s1 -= carry[1] << 21
+	carry[3] = (s3 + (1 << 20)) >> 21
+	s4 += carry[3]
+	s3 -= carry[3] << 21
+	carry[5] = (s5 + (1 << 20)) >> 21
+	s6 += carry[5]
+	s5 -= carry[5] << 21
+	carry[7] = (s7 + (1 << 20)) >> 21
+	s8 += carry[7]
+	s7 -= carry[7] << 21
+	carry[9] = (s9 + (1 << 20)) >> 21
+	s10 += carry[9]
+	s9 -= carry[9] << 21
+	carry[11] = (s11 + (1 << 20)) >> 21
+	s12 += carry[11]
+	s11 -= carry[11] << 21
+
+	s0 += s12 * 666643
+	s1 += s12 * 470296
+	s2 += s12 * 654183
+	s3 -= s12 * 997805
+	s4 += s12 * 136657
+	s5 -= s12 * 683901
+	s12 = 0
+
+	carry[0] = s0 >> 21
+	s1 += carry[0]
+	s0 -= carry[0] << 21
+	carry[1] = s1 >> 21
+	s2 += carry[1]
+	s1 -= carry[1] << 21
+	carry[2] = s2 >> 21
+	s3 += carry[2]
+	s2 -= carry[2] << 21
+	carry[3] = s3 >> 21
+	s4 += carry[3]
+	s3 -= carry[3] << 21
+	carry[4] = s4 >> 21
+	s5 += carry[4]
+	s4 -= carry[4] << 21
+	carry[5] = s5 >> 21
+	s6 += carry[5]
+	s5 -= carry[5] << 21
+	carry[6] = s6 >> 21
+	s7 += carry[6]
+	s6 -= carry[6] << 21
+	carry[7] = s7 >> 21
+	s8 += carry[7]
+	s7 -= carry[7] << 21
+	carry[8] = s8 >> 21
+	s9 += carry[8]
+	s8 -= carry[8] << 21
+	carry[9] = s9 >> 21
+	s10 += carry[9]
+	s9 -= carry[9] << 21
+	carry[10] = s10 >> 21
+	s11 += carry[10]
+	s10 -= carry[10] << 21
+	carry[11] = s11 >> 21
+	s12 += carry[11]
+	s11 -= carry[11] << 21
+
+	s0 += s12 * 666643
+	s1 += s12 * 470296
+	s2 += s12 * 654183
+	s3 -= s12 * 997805
+	s4 += s12 * 136657
+	s5 -= s12 * 683901
+	s12 = 0
+
+	carry[0] = s0 >> 21
+	s1 += carry[0]
+	s0 -= carry[0] << 21
+	carry[1] = s1 >> 21
+	s2 += carry[1]
+	s1 -= carry[1] << 21
+	carry[2] = s2 >> 21
+	s3 += carry[2]
+	s2 -= carry[2] << 21
+	carry[3] = s3 >> 21
+	s4 += carry[3]
+	s3 -= carry[3] << 21
+	carry[4] = s4 >> 21
+	s5 += carry[4]
+	s4 -= carry[4] << 21
+	carry[5] = s5 >> 21
+	s6 += carry[5]
+	s5 -= carry[5] << 21
+	carry[6] = s6 >> 21
+	s7 += carry[6]
+	s6 -= carry[6] << 21
+	carry[7] = s7 >> 21
+	s8 += carry[7]
+	s7 -= carry[7] << 21
+	carry[8] = s8 >> 21
+	s9 += carry[8]
+	s8 -= carry[8] << 21
+	carry[9] = s9 >> 21
+	s10 += carry[9]
+	s9 -= carry[9] << 21
+	carry[10] = s10 >> 21
+	s11 += carry[10]
+	s10 -= carry[10] << 21
+
+	out[0] = byte(s0 >> 0)
+	out[1] = byte(s0 >> 8)
+	out[2] = byte((s0 >> 16) | (s1 << 5))
+	out[3] = byte(s1 >> 3)
+	out[4] = byte(s1 >> 11)
+	out[5] = byte((s1 >> 19) | (s2 << 2))
+	out[6] = byte(s2 >> 6)
+	out[7] = byte((s2 >> 14) | (s3 << 7))
+	out[8] = byte(s3 >> 1)
+	out[9] = byte(s3 >> 9)
+	out[10] = byte((s3 >> 17) | (s4 << 4))
+	out[11] = byte(s4 >> 4)
+	out[12] = byte(s4 >> 12)
+	out[13] = byte((s4 >> 20) | (s5 << 1))
+	out[14] = byte(s5 >> 7)
+	out[15] = byte((s5 >> 15) | (s6 << 6))
+	out[16] = byte(s6 >> 2)
+	out[17] = byte(s6 >> 10)
+	out[18] = byte((s6 >> 18) | (s7 << 3))
+	out[19] = byte(s7 >> 5)
+	out[20] = byte(s7 >> 13)
+	out[21] = byte(s8 >> 0)
+	out[22] = byte(s8 >> 8)
+	out[23] = byte((s8 >> 16) | (s9 << 5))
+	out[24] = byte(s9 >> 3)
+	out[25] = byte(s9 >> 11)
+	out[26] = byte((s9 >> 19) | (s10 << 2))
+	out[27] = byte(s10 >> 6)
+	out[28] = byte((s10 >> 14) | (s11 << 7))
+	out[29] = byte(s11 >> 1)
+	out[30] = byte(s11 >> 9)
+	out[31] = byte(s11 >> 17)
+}
+
+// nonAdjacentForm computes a width-w non-adjacent form for this scalar.
+//
+// w must be between 2 and 8, or nonAdjacentForm will panic.
+func (s *Scalar) nonAdjacentForm(w uint) [256]int8 {
+	// This implementation is adapted from the one
+	// in curve25519-dalek and is documented there:
+	// https://github.com/dalek-cryptography/curve25519-dalek/blob/f630041af28e9a405255f98a8a93adca18e4315b/src/scalar.rs#L800-L871
+	if s.s[31] > 127 {
+		panic("scalar has high bit set illegally")
+	}
+	if w < 2 {
+		panic("w must be at least 2 by the definition of NAF")
+	} else if w > 8 {
+		panic("NAF digits must fit in int8")
+	}
+
+	var naf [256]int8
+	var digits [5]uint64
+
+	for i := 0; i < 4; i++ {
+		digits[i] = binary.LittleEndian.Uint64(s.s[i*8:])
+	}
+
+	width := uint64(1 << w)
+	windowMask := uint64(width - 1)
+
+	pos := uint(0)
+	carry := uint64(0)
+	for pos < 256 {
+		indexU64 := pos / 64
+		indexBit := pos % 64
+		var bitBuf uint64
+		if indexBit < 64-w {
+			// This window's bits are contained in a single u64
+			bitBuf = digits[indexU64] >> indexBit
+		} else {
+			// Combine the current 64 bits with bits from the next 64
+			bitBuf = (digits[indexU64] >> indexBit) | (digits[1+indexU64] << (64 - indexBit))
+		}
+
+		// Add carry into the current window
+		window := carry + (bitBuf & windowMask)
+
+		if window&1 == 0 {
+			// If the window value is even, preserve the carry and continue.
+			// Why is the carry preserved?
+			// If carry == 0 and window & 1 == 0,
+			//    then the next carry should be 0
+			// If carry == 1 and window & 1 == 0,
+			//    then bit_buf & 1 == 1 so the next carry should be 1
+			pos += 1
+			continue
+		}
+
+		if window < width/2 {
+			carry = 0
+			naf[pos] = int8(window)
+		} else {
+			carry = 1
+			naf[pos] = int8(window) - int8(width)
+		}
+
+		pos += w
+	}
+	return naf
+}
+
+func (s *Scalar) signedRadix16() [64]int8 {
+	if s.s[31] > 127 {
+		panic("scalar has high bit set illegally")
+	}
+
+	var digits [64]int8
+
+	// Compute unsigned radix-16 digits:
+	for i := 0; i < 32; i++ {
+		digits[2*i] = int8(s.s[i] & 15)
+		digits[2*i+1] = int8((s.s[i] >> 4) & 15)
+	}
+
+	// Recenter coefficients:
+	for i := 0; i < 63; i++ {
+		carry := (digits[i] + 8) >> 4
+		digits[i] -= carry << 4
+		digits[i+1] += carry
+	}
+
+	return digits
+}
diff --git a/contrib/go/_std_1.18/src/crypto/ed25519/internal/edwards25519/scalarmult.go b/contrib/go/_std_1.19/src/crypto/internal/edwards25519/scalarmult.go
index f7ca3cef99..f7ca3cef99 100644
--- a/contrib/go/_std_1.18/src/crypto/ed25519/internal/edwards25519/scalarmult.go
+++ b/contrib/go/_std_1.19/src/crypto/internal/edwards25519/scalarmult.go
diff --git a/contrib/go/_std_1.18/src/crypto/ed25519/internal/edwards25519/tables.go b/contrib/go/_std_1.19/src/crypto/internal/edwards25519/tables.go
index 5ca40f7bfa..5ca40f7bfa 100644
--- a/contrib/go/_std_1.18/src/crypto/ed25519/internal/edwards25519/tables.go
+++ b/contrib/go/_std_1.19/src/crypto/internal/edwards25519/tables.go
diff --git a/contrib/go/_std_1.18/src/crypto/elliptic/internal/fiat/p224.go b/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p224.go
index 4dddeb07a4..4dddeb07a4 100644
--- a/contrib/go/_std_1.18/src/crypto/elliptic/internal/fiat/p224.go
+++ b/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p224.go
diff --git a/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p224_fiat64.go b/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p224_fiat64.go
new file mode 100644
index 0000000000..9337bfefef
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p224_fiat64.go
@@ -0,0 +1,1461 @@
+// Code generated by Fiat Cryptography. DO NOT EDIT.
+//
+// Autogenerated: word_by_word_montgomery --lang Go --no-wide-int --cmovznz-by-mul --relax-primitive-carry-to-bitwidth 32,64 --internal-static --public-function-case camelCase --public-type-case camelCase --private-function-case camelCase --private-type-case camelCase --doc-text-before-function-name '' --doc-newline-before-package-declaration --doc-prepend-header 'Code generated by Fiat Cryptography. DO NOT EDIT.' --package-name fiat --no-prefix-fiat p224 64 '2^224 - 2^96 + 1' mul square add sub one from_montgomery to_montgomery selectznz to_bytes from_bytes
+//
+// curve description: p224
+//
+// machine_wordsize = 64 (from "64")
+//
+// requested operations: mul, square, add, sub, one, from_montgomery, to_montgomery, selectznz, to_bytes, from_bytes
+//
+// m = 0xffffffffffffffffffffffffffffffff000000000000000000000001 (from "2^224 - 2^96 + 1")
+//
+//
+//
+// NOTE: In addition to the bounds specified above each function, all
+//
+//   functions synthesized for this Montgomery arithmetic require the
+//
+//   input to be strictly less than the prime modulus (m), and also
+//
+//   require the input to be in the unique saturated representation.
+//
+//   All functions also ensure that these two properties are true of
+//
+//   return values.
+//
+//
+//
+// Computed values:
+//
+//   eval z = z[0] + (z[1] << 64) + (z[2] << 128) + (z[3] << 192)
+//
+//   bytes_eval z = z[0] + (z[1] << 8) + (z[2] << 16) + (z[3] << 24) + (z[4] << 32) + (z[5] << 40) + (z[6] << 48) + (z[7] << 56) + (z[8] << 64) + (z[9] << 72) + (z[10] << 80) + (z[11] << 88) + (z[12] << 96) + (z[13] << 104) + (z[14] << 112) + (z[15] << 120) + (z[16] << 128) + (z[17] << 136) + (z[18] << 144) + (z[19] << 152) + (z[20] << 160) + (z[21] << 168) + (z[22] << 176) + (z[23] << 184) + (z[24] << 192) + (z[25] << 200) + (z[26] << 208) + (z[27] << 216)
+//
+//   twos_complement_eval z = let x1 := z[0] + (z[1] << 64) + (z[2] << 128) + (z[3] << 192) in
+//
+//                            if x1 & (2^256-1) < 2^255 then x1 & (2^256-1) else (x1 & (2^256-1)) - 2^256
+
+package fiat
+
+import "math/bits"
+
+type p224Uint1 uint64 // We use uint64 instead of a more narrow type for performance reasons; see https://github.com/mit-plv/fiat-crypto/pull/1006#issuecomment-892625927
+type p224Int1 int64   // We use uint64 instead of a more narrow type for performance reasons; see https://github.com/mit-plv/fiat-crypto/pull/1006#issuecomment-892625927
+
+// The type p224MontgomeryDomainFieldElement is a field element in the Montgomery domain.
+//
+// Bounds: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
+type p224MontgomeryDomainFieldElement [4]uint64
+
+// The type p224NonMontgomeryDomainFieldElement is a field element NOT in the Montgomery domain.
+//
+// Bounds: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
+type p224NonMontgomeryDomainFieldElement [4]uint64
+
+// p224CmovznzU64 is a single-word conditional move.
+//
+// Postconditions:
+//
+//	out1 = (if arg1 = 0 then arg2 else arg3)
+//
+// Input Bounds:
+//
+//	arg1: [0x0 ~> 0x1]
+//	arg2: [0x0 ~> 0xffffffffffffffff]
+//	arg3: [0x0 ~> 0xffffffffffffffff]
+//
+// Output Bounds:
+//
+//	out1: [0x0 ~> 0xffffffffffffffff]
+func p224CmovznzU64(out1 *uint64, arg1 p224Uint1, arg2 uint64, arg3 uint64) {
+	x1 := (uint64(arg1) * 0xffffffffffffffff)
+	x2 := ((x1 & arg3) | ((^x1) & arg2))
+	*out1 = x2
+}
+
+// p224Mul multiplies two field elements in the Montgomery domain.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//	0 ≤ eval arg2 < m
+//
+// Postconditions:
+//
+//	eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) * eval (from_montgomery arg2)) mod m
+//	0 ≤ eval out1 < m
+func p224Mul(out1 *p224MontgomeryDomainFieldElement, arg1 *p224MontgomeryDomainFieldElement, arg2 *p224MontgomeryDomainFieldElement) {
+	x1 := arg1[1]
+	x2 := arg1[2]
+	x3 := arg1[3]
+	x4 := arg1[0]
+	var x5 uint64
+	var x6 uint64
+	x6, x5 = bits.Mul64(x4, arg2[3])
+	var x7 uint64
+	var x8 uint64
+	x8, x7 = bits.Mul64(x4, arg2[2])
+	var x9 uint64
+	var x10 uint64
+	x10, x9 = bits.Mul64(x4, arg2[1])
+	var x11 uint64
+	var x12 uint64
+	x12, x11 = bits.Mul64(x4, arg2[0])
+	var x13 uint64
+	var x14 uint64
+	x13, x14 = bits.Add64(x12, x9, uint64(0x0))
+	var x15 uint64
+	var x16 uint64
+	x15, x16 = bits.Add64(x10, x7, uint64(p224Uint1(x14)))
+	var x17 uint64
+	var x18 uint64
+	x17, x18 = bits.Add64(x8, x5, uint64(p224Uint1(x16)))
+	x19 := (uint64(p224Uint1(x18)) + x6)
+	var x20 uint64
+	_, x20 = bits.Mul64(x11, 0xffffffffffffffff)
+	var x22 uint64
+	var x23 uint64
+	x23, x22 = bits.Mul64(x20, 0xffffffff)
+	var x24 uint64
+	var x25 uint64
+	x25, x24 = bits.Mul64(x20, 0xffffffffffffffff)
+	var x26 uint64
+	var x27 uint64
+	x27, x26 = bits.Mul64(x20, 0xffffffff00000000)
+	var x28 uint64
+	var x29 uint64
+	x28, x29 = bits.Add64(x27, x24, uint64(0x0))
+	var x30 uint64
+	var x31 uint64
+	x30, x31 = bits.Add64(x25, x22, uint64(p224Uint1(x29)))
+	x32 := (uint64(p224Uint1(x31)) + x23)
+	var x34 uint64
+	_, x34 = bits.Add64(x11, x20, uint64(0x0))
+	var x35 uint64
+	var x36 uint64
+	x35, x36 = bits.Add64(x13, x26, uint64(p224Uint1(x34)))
+	var x37 uint64
+	var x38 uint64
+	x37, x38 = bits.Add64(x15, x28, uint64(p224Uint1(x36)))
+	var x39 uint64
+	var x40 uint64
+	x39, x40 = bits.Add64(x17, x30, uint64(p224Uint1(x38)))
+	var x41 uint64
+	var x42 uint64
+	x41, x42 = bits.Add64(x19, x32, uint64(p224Uint1(x40)))
+	var x43 uint64
+	var x44 uint64
+	x44, x43 = bits.Mul64(x1, arg2[3])
+	var x45 uint64
+	var x46 uint64
+	x46, x45 = bits.Mul64(x1, arg2[2])
+	var x47 uint64
+	var x48 uint64
+	x48, x47 = bits.Mul64(x1, arg2[1])
+	var x49 uint64
+	var x50 uint64
+	x50, x49 = bits.Mul64(x1, arg2[0])
+	var x51 uint64
+	var x52 uint64
+	x51, x52 = bits.Add64(x50, x47, uint64(0x0))
+	var x53 uint64
+	var x54 uint64
+	x53, x54 = bits.Add64(x48, x45, uint64(p224Uint1(x52)))
+	var x55 uint64
+	var x56 uint64
+	x55, x56 = bits.Add64(x46, x43, uint64(p224Uint1(x54)))
+	x57 := (uint64(p224Uint1(x56)) + x44)
+	var x58 uint64
+	var x59 uint64
+	x58, x59 = bits.Add64(x35, x49, uint64(0x0))
+	var x60 uint64
+	var x61 uint64
+	x60, x61 = bits.Add64(x37, x51, uint64(p224Uint1(x59)))
+	var x62 uint64
+	var x63 uint64
+	x62, x63 = bits.Add64(x39, x53, uint64(p224Uint1(x61)))
+	var x64 uint64
+	var x65 uint64
+	x64, x65 = bits.Add64(x41, x55, uint64(p224Uint1(x63)))
+	var x66 uint64
+	var x67 uint64
+	x66, x67 = bits.Add64(uint64(p224Uint1(x42)), x57, uint64(p224Uint1(x65)))
+	var x68 uint64
+	_, x68 = bits.Mul64(x58, 0xffffffffffffffff)
+	var x70 uint64
+	var x71 uint64
+	x71, x70 = bits.Mul64(x68, 0xffffffff)
+	var x72 uint64
+	var x73 uint64
+	x73, x72 = bits.Mul64(x68, 0xffffffffffffffff)
+	var x74 uint64
+	var x75 uint64
+	x75, x74 = bits.Mul64(x68, 0xffffffff00000000)
+	var x76 uint64
+	var x77 uint64
+	x76, x77 = bits.Add64(x75, x72, uint64(0x0))
+	var x78 uint64
+	var x79 uint64
+	x78, x79 = bits.Add64(x73, x70, uint64(p224Uint1(x77)))
+	x80 := (uint64(p224Uint1(x79)) + x71)
+	var x82 uint64
+	_, x82 = bits.Add64(x58, x68, uint64(0x0))
+	var x83 uint64
+	var x84 uint64
+	x83, x84 = bits.Add64(x60, x74, uint64(p224Uint1(x82)))
+	var x85 uint64
+	var x86 uint64
+	x85, x86 = bits.Add64(x62, x76, uint64(p224Uint1(x84)))
+	var x87 uint64
+	var x88 uint64
+	x87, x88 = bits.Add64(x64, x78, uint64(p224Uint1(x86)))
+	var x89 uint64
+	var x90 uint64
+	x89, x90 = bits.Add64(x66, x80, uint64(p224Uint1(x88)))
+	x91 := (uint64(p224Uint1(x90)) + uint64(p224Uint1(x67)))
+	var x92 uint64
+	var x93 uint64
+	x93, x92 = bits.Mul64(x2, arg2[3])
+	var x94 uint64
+	var x95 uint64
+	x95, x94 = bits.Mul64(x2, arg2[2])
+	var x96 uint64
+	var x97 uint64
+	x97, x96 = bits.Mul64(x2, arg2[1])
+	var x98 uint64
+	var x99 uint64
+	x99, x98 = bits.Mul64(x2, arg2[0])
+	var x100 uint64
+	var x101 uint64
+	x100, x101 = bits.Add64(x99, x96, uint64(0x0))
+	var x102 uint64
+	var x103 uint64
+	x102, x103 = bits.Add64(x97, x94, uint64(p224Uint1(x101)))
+	var x104 uint64
+	var x105 uint64
+	x104, x105 = bits.Add64(x95, x92, uint64(p224Uint1(x103)))
+	x106 := (uint64(p224Uint1(x105)) + x93)
+	var x107 uint64
+	var x108 uint64
+	x107, x108 = bits.Add64(x83, x98, uint64(0x0))
+	var x109 uint64
+	var x110 uint64
+	x109, x110 = bits.Add64(x85, x100, uint64(p224Uint1(x108)))
+	var x111 uint64
+	var x112 uint64
+	x111, x112 = bits.Add64(x87, x102, uint64(p224Uint1(x110)))
+	var x113 uint64
+	var x114 uint64
+	x113, x114 = bits.Add64(x89, x104, uint64(p224Uint1(x112)))
+	var x115 uint64
+	var x116 uint64
+	x115, x116 = bits.Add64(x91, x106, uint64(p224Uint1(x114)))
+	var x117 uint64
+	_, x117 = bits.Mul64(x107, 0xffffffffffffffff)
+	var x119 uint64
+	var x120 uint64
+	x120, x119 = bits.Mul64(x117, 0xffffffff)
+	var x121 uint64
+	var x122 uint64
+	x122, x121 = bits.Mul64(x117, 0xffffffffffffffff)
+	var x123 uint64
+	var x124 uint64
+	x124, x123 = bits.Mul64(x117, 0xffffffff00000000)
+	var x125 uint64
+	var x126 uint64
+	x125, x126 = bits.Add64(x124, x121, uint64(0x0))
+	var x127 uint64
+	var x128 uint64
+	x127, x128 = bits.Add64(x122, x119, uint64(p224Uint1(x126)))
+	x129 := (uint64(p224Uint1(x128)) + x120)
+	var x131 uint64
+	_, x131 = bits.Add64(x107, x117, uint64(0x0))
+	var x132 uint64
+	var x133 uint64
+	x132, x133 = bits.Add64(x109, x123, uint64(p224Uint1(x131)))
+	var x134 uint64
+	var x135 uint64
+	x134, x135 = bits.Add64(x111, x125, uint64(p224Uint1(x133)))
+	var x136 uint64
+	var x137 uint64
+	x136, x137 = bits.Add64(x113, x127, uint64(p224Uint1(x135)))
+	var x138 uint64
+	var x139 uint64
+	x138, x139 = bits.Add64(x115, x129, uint64(p224Uint1(x137)))
+	x140 := (uint64(p224Uint1(x139)) + uint64(p224Uint1(x116)))
+	var x141 uint64
+	var x142 uint64
+	x142, x141 = bits.Mul64(x3, arg2[3])
+	var x143 uint64
+	var x144 uint64
+	x144, x143 = bits.Mul64(x3, arg2[2])
+	var x145 uint64
+	var x146 uint64
+	x146, x145 = bits.Mul64(x3, arg2[1])
+	var x147 uint64
+	var x148 uint64
+	x148, x147 = bits.Mul64(x3, arg2[0])
+	var x149 uint64
+	var x150 uint64
+	x149, x150 = bits.Add64(x148, x145, uint64(0x0))
+	var x151 uint64
+	var x152 uint64
+	x151, x152 = bits.Add64(x146, x143, uint64(p224Uint1(x150)))
+	var x153 uint64
+	var x154 uint64
+	x153, x154 = bits.Add64(x144, x141, uint64(p224Uint1(x152)))
+	x155 := (uint64(p224Uint1(x154)) + x142)
+	var x156 uint64
+	var x157 uint64
+	x156, x157 = bits.Add64(x132, x147, uint64(0x0))
+	var x158 uint64
+	var x159 uint64
+	x158, x159 = bits.Add64(x134, x149, uint64(p224Uint1(x157)))
+	var x160 uint64
+	var x161 uint64
+	x160, x161 = bits.Add64(x136, x151, uint64(p224Uint1(x159)))
+	var x162 uint64
+	var x163 uint64
+	x162, x163 = bits.Add64(x138, x153, uint64(p224Uint1(x161)))
+	var x164 uint64
+	var x165 uint64
+	x164, x165 = bits.Add64(x140, x155, uint64(p224Uint1(x163)))
+	var x166 uint64
+	_, x166 = bits.Mul64(x156, 0xffffffffffffffff)
+	var x168 uint64
+	var x169 uint64
+	x169, x168 = bits.Mul64(x166, 0xffffffff)
+	var x170 uint64
+	var x171 uint64
+	x171, x170 = bits.Mul64(x166, 0xffffffffffffffff)
+	var x172 uint64
+	var x173 uint64
+	x173, x172 = bits.Mul64(x166, 0xffffffff00000000)
+	var x174 uint64
+	var x175 uint64
+	x174, x175 = bits.Add64(x173, x170, uint64(0x0))
+	var x176 uint64
+	var x177 uint64
+	x176, x177 = bits.Add64(x171, x168, uint64(p224Uint1(x175)))
+	x178 := (uint64(p224Uint1(x177)) + x169)
+	var x180 uint64
+	_, x180 = bits.Add64(x156, x166, uint64(0x0))
+	var x181 uint64
+	var x182 uint64
+	x181, x182 = bits.Add64(x158, x172, uint64(p224Uint1(x180)))
+	var x183 uint64
+	var x184 uint64
+	x183, x184 = bits.Add64(x160, x174, uint64(p224Uint1(x182)))
+	var x185 uint64
+	var x186 uint64
+	x185, x186 = bits.Add64(x162, x176, uint64(p224Uint1(x184)))
+	var x187 uint64
+	var x188 uint64
+	x187, x188 = bits.Add64(x164, x178, uint64(p224Uint1(x186)))
+	x189 := (uint64(p224Uint1(x188)) + uint64(p224Uint1(x165)))
+	var x190 uint64
+	var x191 uint64
+	x190, x191 = bits.Sub64(x181, uint64(0x1), uint64(0x0))
+	var x192 uint64
+	var x193 uint64
+	x192, x193 = bits.Sub64(x183, 0xffffffff00000000, uint64(p224Uint1(x191)))
+	var x194 uint64
+	var x195 uint64
+	x194, x195 = bits.Sub64(x185, 0xffffffffffffffff, uint64(p224Uint1(x193)))
+	var x196 uint64
+	var x197 uint64
+	x196, x197 = bits.Sub64(x187, 0xffffffff, uint64(p224Uint1(x195)))
+	var x199 uint64
+	_, x199 = bits.Sub64(x189, uint64(0x0), uint64(p224Uint1(x197)))
+	var x200 uint64
+	p224CmovznzU64(&x200, p224Uint1(x199), x190, x181)
+	var x201 uint64
+	p224CmovznzU64(&x201, p224Uint1(x199), x192, x183)
+	var x202 uint64
+	p224CmovznzU64(&x202, p224Uint1(x199), x194, x185)
+	var x203 uint64
+	p224CmovznzU64(&x203, p224Uint1(x199), x196, x187)
+	out1[0] = x200
+	out1[1] = x201
+	out1[2] = x202
+	out1[3] = x203
+}
+
+// p224Square squares a field element in the Montgomery domain.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//
+// Postconditions:
+//
+//	eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) * eval (from_montgomery arg1)) mod m
+//	0 ≤ eval out1 < m
+func p224Square(out1 *p224MontgomeryDomainFieldElement, arg1 *p224MontgomeryDomainFieldElement) {
+	x1 := arg1[1]
+	x2 := arg1[2]
+	x3 := arg1[3]
+	x4 := arg1[0]
+	var x5 uint64
+	var x6 uint64
+	x6, x5 = bits.Mul64(x4, arg1[3])
+	var x7 uint64
+	var x8 uint64
+	x8, x7 = bits.Mul64(x4, arg1[2])
+	var x9 uint64
+	var x10 uint64
+	x10, x9 = bits.Mul64(x4, arg1[1])
+	var x11 uint64
+	var x12 uint64
+	x12, x11 = bits.Mul64(x4, arg1[0])
+	var x13 uint64
+	var x14 uint64
+	x13, x14 = bits.Add64(x12, x9, uint64(0x0))
+	var x15 uint64
+	var x16 uint64
+	x15, x16 = bits.Add64(x10, x7, uint64(p224Uint1(x14)))
+	var x17 uint64
+	var x18 uint64
+	x17, x18 = bits.Add64(x8, x5, uint64(p224Uint1(x16)))
+	x19 := (uint64(p224Uint1(x18)) + x6)
+	var x20 uint64
+	_, x20 = bits.Mul64(x11, 0xffffffffffffffff)
+	var x22 uint64
+	var x23 uint64
+	x23, x22 = bits.Mul64(x20, 0xffffffff)
+	var x24 uint64
+	var x25 uint64
+	x25, x24 = bits.Mul64(x20, 0xffffffffffffffff)
+	var x26 uint64
+	var x27 uint64
+	x27, x26 = bits.Mul64(x20, 0xffffffff00000000)
+	var x28 uint64
+	var x29 uint64
+	x28, x29 = bits.Add64(x27, x24, uint64(0x0))
+	var x30 uint64
+	var x31 uint64
+	x30, x31 = bits.Add64(x25, x22, uint64(p224Uint1(x29)))
+	x32 := (uint64(p224Uint1(x31)) + x23)
+	var x34 uint64
+	_, x34 = bits.Add64(x11, x20, uint64(0x0))
+	var x35 uint64
+	var x36 uint64
+	x35, x36 = bits.Add64(x13, x26, uint64(p224Uint1(x34)))
+	var x37 uint64
+	var x38 uint64
+	x37, x38 = bits.Add64(x15, x28, uint64(p224Uint1(x36)))
+	var x39 uint64
+	var x40 uint64
+	x39, x40 = bits.Add64(x17, x30, uint64(p224Uint1(x38)))
+	var x41 uint64
+	var x42 uint64
+	x41, x42 = bits.Add64(x19, x32, uint64(p224Uint1(x40)))
+	var x43 uint64
+	var x44 uint64
+	x44, x43 = bits.Mul64(x1, arg1[3])
+	var x45 uint64
+	var x46 uint64
+	x46, x45 = bits.Mul64(x1, arg1[2])
+	var x47 uint64
+	var x48 uint64
+	x48, x47 = bits.Mul64(x1, arg1[1])
+	var x49 uint64
+	var x50 uint64
+	x50, x49 = bits.Mul64(x1, arg1[0])
+	var x51 uint64
+	var x52 uint64
+	x51, x52 = bits.Add64(x50, x47, uint64(0x0))
+	var x53 uint64
+	var x54 uint64
+	x53, x54 = bits.Add64(x48, x45, uint64(p224Uint1(x52)))
+	var x55 uint64
+	var x56 uint64
+	x55, x56 = bits.Add64(x46, x43, uint64(p224Uint1(x54)))
+	x57 := (uint64(p224Uint1(x56)) + x44)
+	var x58 uint64
+	var x59 uint64
+	x58, x59 = bits.Add64(x35, x49, uint64(0x0))
+	var x60 uint64
+	var x61 uint64
+	x60, x61 = bits.Add64(x37, x51, uint64(p224Uint1(x59)))
+	var x62 uint64
+	var x63 uint64
+	x62, x63 = bits.Add64(x39, x53, uint64(p224Uint1(x61)))
+	var x64 uint64
+	var x65 uint64
+	x64, x65 = bits.Add64(x41, x55, uint64(p224Uint1(x63)))
+	var x66 uint64
+	var x67 uint64
+	x66, x67 = bits.Add64(uint64(p224Uint1(x42)), x57, uint64(p224Uint1(x65)))
+	var x68 uint64
+	_, x68 = bits.Mul64(x58, 0xffffffffffffffff)
+	var x70 uint64
+	var x71 uint64
+	x71, x70 = bits.Mul64(x68, 0xffffffff)
+	var x72 uint64
+	var x73 uint64
+	x73, x72 = bits.Mul64(x68, 0xffffffffffffffff)
+	var x74 uint64
+	var x75 uint64
+	x75, x74 = bits.Mul64(x68, 0xffffffff00000000)
+	var x76 uint64
+	var x77 uint64
+	x76, x77 = bits.Add64(x75, x72, uint64(0x0))
+	var x78 uint64
+	var x79 uint64
+	x78, x79 = bits.Add64(x73, x70, uint64(p224Uint1(x77)))
+	x80 := (uint64(p224Uint1(x79)) + x71)
+	var x82 uint64
+	_, x82 = bits.Add64(x58, x68, uint64(0x0))
+	var x83 uint64
+	var x84 uint64
+	x83, x84 = bits.Add64(x60, x74, uint64(p224Uint1(x82)))
+	var x85 uint64
+	var x86 uint64
+	x85, x86 = bits.Add64(x62, x76, uint64(p224Uint1(x84)))
+	var x87 uint64
+	var x88 uint64
+	x87, x88 = bits.Add64(x64, x78, uint64(p224Uint1(x86)))
+	var x89 uint64
+	var x90 uint64
+	x89, x90 = bits.Add64(x66, x80, uint64(p224Uint1(x88)))
+	x91 := (uint64(p224Uint1(x90)) + uint64(p224Uint1(x67)))
+	var x92 uint64
+	var x93 uint64
+	x93, x92 = bits.Mul64(x2, arg1[3])
+	var x94 uint64
+	var x95 uint64
+	x95, x94 = bits.Mul64(x2, arg1[2])
+	var x96 uint64
+	var x97 uint64
+	x97, x96 = bits.Mul64(x2, arg1[1])
+	var x98 uint64
+	var x99 uint64
+	x99, x98 = bits.Mul64(x2, arg1[0])
+	var x100 uint64
+	var x101 uint64
+	x100, x101 = bits.Add64(x99, x96, uint64(0x0))
+	var x102 uint64
+	var x103 uint64
+	x102, x103 = bits.Add64(x97, x94, uint64(p224Uint1(x101)))
+	var x104 uint64
+	var x105 uint64
+	x104, x105 = bits.Add64(x95, x92, uint64(p224Uint1(x103)))
+	x106 := (uint64(p224Uint1(x105)) + x93)
+	var x107 uint64
+	var x108 uint64
+	x107, x108 = bits.Add64(x83, x98, uint64(0x0))
+	var x109 uint64
+	var x110 uint64
+	x109, x110 = bits.Add64(x85, x100, uint64(p224Uint1(x108)))
+	var x111 uint64
+	var x112 uint64
+	x111, x112 = bits.Add64(x87, x102, uint64(p224Uint1(x110)))
+	var x113 uint64
+	var x114 uint64
+	x113, x114 = bits.Add64(x89, x104, uint64(p224Uint1(x112)))
+	var x115 uint64
+	var x116 uint64
+	x115, x116 = bits.Add64(x91, x106, uint64(p224Uint1(x114)))
+	var x117 uint64
+	_, x117 = bits.Mul64(x107, 0xffffffffffffffff)
+	var x119 uint64
+	var x120 uint64
+	x120, x119 = bits.Mul64(x117, 0xffffffff)
+	var x121 uint64
+	var x122 uint64
+	x122, x121 = bits.Mul64(x117, 0xffffffffffffffff)
+	var x123 uint64
+	var x124 uint64
+	x124, x123 = bits.Mul64(x117, 0xffffffff00000000)
+	var x125 uint64
+	var x126 uint64
+	x125, x126 = bits.Add64(x124, x121, uint64(0x0))
+	var x127 uint64
+	var x128 uint64
+	x127, x128 = bits.Add64(x122, x119, uint64(p224Uint1(x126)))
+	x129 := (uint64(p224Uint1(x128)) + x120)
+	var x131 uint64
+	_, x131 = bits.Add64(x107, x117, uint64(0x0))
+	var x132 uint64
+	var x133 uint64
+	x132, x133 = bits.Add64(x109, x123, uint64(p224Uint1(x131)))
+	var x134 uint64
+	var x135 uint64
+	x134, x135 = bits.Add64(x111, x125, uint64(p224Uint1(x133)))
+	var x136 uint64
+	var x137 uint64
+	x136, x137 = bits.Add64(x113, x127, uint64(p224Uint1(x135)))
+	var x138 uint64
+	var x139 uint64
+	x138, x139 = bits.Add64(x115, x129, uint64(p224Uint1(x137)))
+	x140 := (uint64(p224Uint1(x139)) + uint64(p224Uint1(x116)))
+	var x141 uint64
+	var x142 uint64
+	x142, x141 = bits.Mul64(x3, arg1[3])
+	var x143 uint64
+	var x144 uint64
+	x144, x143 = bits.Mul64(x3, arg1[2])
+	var x145 uint64
+	var x146 uint64
+	x146, x145 = bits.Mul64(x3, arg1[1])
+	var x147 uint64
+	var x148 uint64
+	x148, x147 = bits.Mul64(x3, arg1[0])
+	var x149 uint64
+	var x150 uint64
+	x149, x150 = bits.Add64(x148, x145, uint64(0x0))
+	var x151 uint64
+	var x152 uint64
+	x151, x152 = bits.Add64(x146, x143, uint64(p224Uint1(x150)))
+	var x153 uint64
+	var x154 uint64
+	x153, x154 = bits.Add64(x144, x141, uint64(p224Uint1(x152)))
+	x155 := (uint64(p224Uint1(x154)) + x142)
+	var x156 uint64
+	var x157 uint64
+	x156, x157 = bits.Add64(x132, x147, uint64(0x0))
+	var x158 uint64
+	var x159 uint64
+	x158, x159 = bits.Add64(x134, x149, uint64(p224Uint1(x157)))
+	var x160 uint64
+	var x161 uint64
+	x160, x161 = bits.Add64(x136, x151, uint64(p224Uint1(x159)))
+	var x162 uint64
+	var x163 uint64
+	x162, x163 = bits.Add64(x138, x153, uint64(p224Uint1(x161)))
+	var x164 uint64
+	var x165 uint64
+	x164, x165 = bits.Add64(x140, x155, uint64(p224Uint1(x163)))
+	var x166 uint64
+	_, x166 = bits.Mul64(x156, 0xffffffffffffffff)
+	var x168 uint64
+	var x169 uint64
+	x169, x168 = bits.Mul64(x166, 0xffffffff)
+	var x170 uint64
+	var x171 uint64
+	x171, x170 = bits.Mul64(x166, 0xffffffffffffffff)
+	var x172 uint64
+	var x173 uint64
+	x173, x172 = bits.Mul64(x166, 0xffffffff00000000)
+	var x174 uint64
+	var x175 uint64
+	x174, x175 = bits.Add64(x173, x170, uint64(0x0))
+	var x176 uint64
+	var x177 uint64
+	x176, x177 = bits.Add64(x171, x168, uint64(p224Uint1(x175)))
+	x178 := (uint64(p224Uint1(x177)) + x169)
+	var x180 uint64
+	_, x180 = bits.Add64(x156, x166, uint64(0x0))
+	var x181 uint64
+	var x182 uint64
+	x181, x182 = bits.Add64(x158, x172, uint64(p224Uint1(x180)))
+	var x183 uint64
+	var x184 uint64
+	x183, x184 = bits.Add64(x160, x174, uint64(p224Uint1(x182)))
+	var x185 uint64
+	var x186 uint64
+	x185, x186 = bits.Add64(x162, x176, uint64(p224Uint1(x184)))
+	var x187 uint64
+	var x188 uint64
+	x187, x188 = bits.Add64(x164, x178, uint64(p224Uint1(x186)))
+	x189 := (uint64(p224Uint1(x188)) + uint64(p224Uint1(x165)))
+	var x190 uint64
+	var x191 uint64
+	x190, x191 = bits.Sub64(x181, uint64(0x1), uint64(0x0))
+	var x192 uint64
+	var x193 uint64
+	x192, x193 = bits.Sub64(x183, 0xffffffff00000000, uint64(p224Uint1(x191)))
+	var x194 uint64
+	var x195 uint64
+	x194, x195 = bits.Sub64(x185, 0xffffffffffffffff, uint64(p224Uint1(x193)))
+	var x196 uint64
+	var x197 uint64
+	x196, x197 = bits.Sub64(x187, 0xffffffff, uint64(p224Uint1(x195)))
+	var x199 uint64
+	_, x199 = bits.Sub64(x189, uint64(0x0), uint64(p224Uint1(x197)))
+	var x200 uint64
+	p224CmovznzU64(&x200, p224Uint1(x199), x190, x181)
+	var x201 uint64
+	p224CmovznzU64(&x201, p224Uint1(x199), x192, x183)
+	var x202 uint64
+	p224CmovznzU64(&x202, p224Uint1(x199), x194, x185)
+	var x203 uint64
+	p224CmovznzU64(&x203, p224Uint1(x199), x196, x187)
+	out1[0] = x200
+	out1[1] = x201
+	out1[2] = x202
+	out1[3] = x203
+}
+
+// p224Add adds two field elements in the Montgomery domain.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//	0 ≤ eval arg2 < m
+//
+// Postconditions:
+//
+//	eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) + eval (from_montgomery arg2)) mod m
+//	0 ≤ eval out1 < m
+func p224Add(out1 *p224MontgomeryDomainFieldElement, arg1 *p224MontgomeryDomainFieldElement, arg2 *p224MontgomeryDomainFieldElement) {
+	var x1 uint64
+	var x2 uint64
+	x1, x2 = bits.Add64(arg1[0], arg2[0], uint64(0x0))
+	var x3 uint64
+	var x4 uint64
+	x3, x4 = bits.Add64(arg1[1], arg2[1], uint64(p224Uint1(x2)))
+	var x5 uint64
+	var x6 uint64
+	x5, x6 = bits.Add64(arg1[2], arg2[2], uint64(p224Uint1(x4)))
+	var x7 uint64
+	var x8 uint64
+	x7, x8 = bits.Add64(arg1[3], arg2[3], uint64(p224Uint1(x6)))
+	var x9 uint64
+	var x10 uint64
+	x9, x10 = bits.Sub64(x1, uint64(0x1), uint64(0x0))
+	var x11 uint64
+	var x12 uint64
+	x11, x12 = bits.Sub64(x3, 0xffffffff00000000, uint64(p224Uint1(x10)))
+	var x13 uint64
+	var x14 uint64
+	x13, x14 = bits.Sub64(x5, 0xffffffffffffffff, uint64(p224Uint1(x12)))
+	var x15 uint64
+	var x16 uint64
+	x15, x16 = bits.Sub64(x7, 0xffffffff, uint64(p224Uint1(x14)))
+	var x18 uint64
+	_, x18 = bits.Sub64(uint64(p224Uint1(x8)), uint64(0x0), uint64(p224Uint1(x16)))
+	var x19 uint64
+	p224CmovznzU64(&x19, p224Uint1(x18), x9, x1)
+	var x20 uint64
+	p224CmovznzU64(&x20, p224Uint1(x18), x11, x3)
+	var x21 uint64
+	p224CmovznzU64(&x21, p224Uint1(x18), x13, x5)
+	var x22 uint64
+	p224CmovznzU64(&x22, p224Uint1(x18), x15, x7)
+	out1[0] = x19
+	out1[1] = x20
+	out1[2] = x21
+	out1[3] = x22
+}
+
+// p224Sub subtracts two field elements in the Montgomery domain.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//	0 ≤ eval arg2 < m
+//
+// Postconditions:
+//
+//	eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) - eval (from_montgomery arg2)) mod m
+//	0 ≤ eval out1 < m
+func p224Sub(out1 *p224MontgomeryDomainFieldElement, arg1 *p224MontgomeryDomainFieldElement, arg2 *p224MontgomeryDomainFieldElement) {
+	var x1 uint64
+	var x2 uint64
+	x1, x2 = bits.Sub64(arg1[0], arg2[0], uint64(0x0))
+	var x3 uint64
+	var x4 uint64
+	x3, x4 = bits.Sub64(arg1[1], arg2[1], uint64(p224Uint1(x2)))
+	var x5 uint64
+	var x6 uint64
+	x5, x6 = bits.Sub64(arg1[2], arg2[2], uint64(p224Uint1(x4)))
+	var x7 uint64
+	var x8 uint64
+	x7, x8 = bits.Sub64(arg1[3], arg2[3], uint64(p224Uint1(x6)))
+	var x9 uint64
+	p224CmovznzU64(&x9, p224Uint1(x8), uint64(0x0), 0xffffffffffffffff)
+	var x10 uint64
+	var x11 uint64
+	x10, x11 = bits.Add64(x1, uint64((p224Uint1(x9) & 0x1)), uint64(0x0))
+	var x12 uint64
+	var x13 uint64
+	x12, x13 = bits.Add64(x3, (x9 & 0xffffffff00000000), uint64(p224Uint1(x11)))
+	var x14 uint64
+	var x15 uint64
+	x14, x15 = bits.Add64(x5, x9, uint64(p224Uint1(x13)))
+	var x16 uint64
+	x16, _ = bits.Add64(x7, (x9 & 0xffffffff), uint64(p224Uint1(x15)))
+	out1[0] = x10
+	out1[1] = x12
+	out1[2] = x14
+	out1[3] = x16
+}
+
+// p224SetOne returns the field element one in the Montgomery domain.
+//
+// Postconditions:
+//
+//	eval (from_montgomery out1) mod m = 1 mod m
+//	0 ≤ eval out1 < m
+func p224SetOne(out1 *p224MontgomeryDomainFieldElement) {
+	out1[0] = 0xffffffff00000000
+	out1[1] = 0xffffffffffffffff
+	out1[2] = uint64(0x0)
+	out1[3] = uint64(0x0)
+}
+
+// p224FromMontgomery translates a field element out of the Montgomery domain.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//
+// Postconditions:
+//
+//	eval out1 mod m = (eval arg1 * ((2^64)⁻¹ mod m)^4) mod m
+//	0 ≤ eval out1 < m
+func p224FromMontgomery(out1 *p224NonMontgomeryDomainFieldElement, arg1 *p224MontgomeryDomainFieldElement) {
+	x1 := arg1[0]
+	var x2 uint64
+	_, x2 = bits.Mul64(x1, 0xffffffffffffffff)
+	var x4 uint64
+	var x5 uint64
+	x5, x4 = bits.Mul64(x2, 0xffffffff)
+	var x6 uint64
+	var x7 uint64
+	x7, x6 = bits.Mul64(x2, 0xffffffffffffffff)
+	var x8 uint64
+	var x9 uint64
+	x9, x8 = bits.Mul64(x2, 0xffffffff00000000)
+	var x10 uint64
+	var x11 uint64
+	x10, x11 = bits.Add64(x9, x6, uint64(0x0))
+	var x12 uint64
+	var x13 uint64
+	x12, x13 = bits.Add64(x7, x4, uint64(p224Uint1(x11)))
+	var x15 uint64
+	_, x15 = bits.Add64(x1, x2, uint64(0x0))
+	var x16 uint64
+	var x17 uint64
+	x16, x17 = bits.Add64(uint64(0x0), x8, uint64(p224Uint1(x15)))
+	var x18 uint64
+	var x19 uint64
+	x18, x19 = bits.Add64(uint64(0x0), x10, uint64(p224Uint1(x17)))
+	var x20 uint64
+	var x21 uint64
+	x20, x21 = bits.Add64(uint64(0x0), x12, uint64(p224Uint1(x19)))
+	var x22 uint64
+	var x23 uint64
+	x22, x23 = bits.Add64(x16, arg1[1], uint64(0x0))
+	var x24 uint64
+	var x25 uint64
+	x24, x25 = bits.Add64(x18, uint64(0x0), uint64(p224Uint1(x23)))
+	var x26 uint64
+	var x27 uint64
+	x26, x27 = bits.Add64(x20, uint64(0x0), uint64(p224Uint1(x25)))
+	var x28 uint64
+	_, x28 = bits.Mul64(x22, 0xffffffffffffffff)
+	var x30 uint64
+	var x31 uint64
+	x31, x30 = bits.Mul64(x28, 0xffffffff)
+	var x32 uint64
+	var x33 uint64
+	x33, x32 = bits.Mul64(x28, 0xffffffffffffffff)
+	var x34 uint64
+	var x35 uint64
+	x35, x34 = bits.Mul64(x28, 0xffffffff00000000)
+	var x36 uint64
+	var x37 uint64
+	x36, x37 = bits.Add64(x35, x32, uint64(0x0))
+	var x38 uint64
+	var x39 uint64
+	x38, x39 = bits.Add64(x33, x30, uint64(p224Uint1(x37)))
+	var x41 uint64
+	_, x41 = bits.Add64(x22, x28, uint64(0x0))
+	var x42 uint64
+	var x43 uint64
+	x42, x43 = bits.Add64(x24, x34, uint64(p224Uint1(x41)))
+	var x44 uint64
+	var x45 uint64
+	x44, x45 = bits.Add64(x26, x36, uint64(p224Uint1(x43)))
+	var x46 uint64
+	var x47 uint64
+	x46, x47 = bits.Add64((uint64(p224Uint1(x27)) + (uint64(p224Uint1(x21)) + (uint64(p224Uint1(x13)) + x5))), x38, uint64(p224Uint1(x45)))
+	var x48 uint64
+	var x49 uint64
+	x48, x49 = bits.Add64(x42, arg1[2], uint64(0x0))
+	var x50 uint64
+	var x51 uint64
+	x50, x51 = bits.Add64(x44, uint64(0x0), uint64(p224Uint1(x49)))
+	var x52 uint64
+	var x53 uint64
+	x52, x53 = bits.Add64(x46, uint64(0x0), uint64(p224Uint1(x51)))
+	var x54 uint64
+	_, x54 = bits.Mul64(x48, 0xffffffffffffffff)
+	var x56 uint64
+	var x57 uint64
+	x57, x56 = bits.Mul64(x54, 0xffffffff)
+	var x58 uint64
+	var x59 uint64
+	x59, x58 = bits.Mul64(x54, 0xffffffffffffffff)
+	var x60 uint64
+	var x61 uint64
+	x61, x60 = bits.Mul64(x54, 0xffffffff00000000)
+	var x62 uint64
+	var x63 uint64
+	x62, x63 = bits.Add64(x61, x58, uint64(0x0))
+	var x64 uint64
+	var x65 uint64
+	x64, x65 = bits.Add64(x59, x56, uint64(p224Uint1(x63)))
+	var x67 uint64
+	_, x67 = bits.Add64(x48, x54, uint64(0x0))
+	var x68 uint64
+	var x69 uint64
+	x68, x69 = bits.Add64(x50, x60, uint64(p224Uint1(x67)))
+	var x70 uint64
+	var x71 uint64
+	x70, x71 = bits.Add64(x52, x62, uint64(p224Uint1(x69)))
+	var x72 uint64
+	var x73 uint64
+	x72, x73 = bits.Add64((uint64(p224Uint1(x53)) + (uint64(p224Uint1(x47)) + (uint64(p224Uint1(x39)) + x31))), x64, uint64(p224Uint1(x71)))
+	var x74 uint64
+	var x75 uint64
+	x74, x75 = bits.Add64(x68, arg1[3], uint64(0x0))
+	var x76 uint64
+	var x77 uint64
+	x76, x77 = bits.Add64(x70, uint64(0x0), uint64(p224Uint1(x75)))
+	var x78 uint64
+	var x79 uint64
+	x78, x79 = bits.Add64(x72, uint64(0x0), uint64(p224Uint1(x77)))
+	var x80 uint64
+	_, x80 = bits.Mul64(x74, 0xffffffffffffffff)
+	var x82 uint64
+	var x83 uint64
+	x83, x82 = bits.Mul64(x80, 0xffffffff)
+	var x84 uint64
+	var x85 uint64
+	x85, x84 = bits.Mul64(x80, 0xffffffffffffffff)
+	var x86 uint64
+	var x87 uint64
+	x87, x86 = bits.Mul64(x80, 0xffffffff00000000)
+	var x88 uint64
+	var x89 uint64
+	x88, x89 = bits.Add64(x87, x84, uint64(0x0))
+	var x90 uint64
+	var x91 uint64
+	x90, x91 = bits.Add64(x85, x82, uint64(p224Uint1(x89)))
+	var x93 uint64
+	_, x93 = bits.Add64(x74, x80, uint64(0x0))
+	var x94 uint64
+	var x95 uint64
+	x94, x95 = bits.Add64(x76, x86, uint64(p224Uint1(x93)))
+	var x96 uint64
+	var x97 uint64
+	x96, x97 = bits.Add64(x78, x88, uint64(p224Uint1(x95)))
+	var x98 uint64
+	var x99 uint64
+	x98, x99 = bits.Add64((uint64(p224Uint1(x79)) + (uint64(p224Uint1(x73)) + (uint64(p224Uint1(x65)) + x57))), x90, uint64(p224Uint1(x97)))
+	x100 := (uint64(p224Uint1(x99)) + (uint64(p224Uint1(x91)) + x83))
+	var x101 uint64
+	var x102 uint64
+	x101, x102 = bits.Sub64(x94, uint64(0x1), uint64(0x0))
+	var x103 uint64
+	var x104 uint64
+	x103, x104 = bits.Sub64(x96, 0xffffffff00000000, uint64(p224Uint1(x102)))
+	var x105 uint64
+	var x106 uint64
+	x105, x106 = bits.Sub64(x98, 0xffffffffffffffff, uint64(p224Uint1(x104)))
+	var x107 uint64
+	var x108 uint64
+	x107, x108 = bits.Sub64(x100, 0xffffffff, uint64(p224Uint1(x106)))
+	var x110 uint64
+	_, x110 = bits.Sub64(uint64(0x0), uint64(0x0), uint64(p224Uint1(x108)))
+	var x111 uint64
+	p224CmovznzU64(&x111, p224Uint1(x110), x101, x94)
+	var x112 uint64
+	p224CmovznzU64(&x112, p224Uint1(x110), x103, x96)
+	var x113 uint64
+	p224CmovznzU64(&x113, p224Uint1(x110), x105, x98)
+	var x114 uint64
+	p224CmovznzU64(&x114, p224Uint1(x110), x107, x100)
+	out1[0] = x111
+	out1[1] = x112
+	out1[2] = x113
+	out1[3] = x114
+}
+
+// p224ToMontgomery translates a field element into the Montgomery domain.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//
+// Postconditions:
+//
+//	eval (from_montgomery out1) mod m = eval arg1 mod m
+//	0 ≤ eval out1 < m
+func p224ToMontgomery(out1 *p224MontgomeryDomainFieldElement, arg1 *p224NonMontgomeryDomainFieldElement) {
+	x1 := arg1[1]
+	x2 := arg1[2]
+	x3 := arg1[3]
+	x4 := arg1[0]
+	var x5 uint64
+	var x6 uint64
+	x6, x5 = bits.Mul64(x4, 0xffffffff)
+	var x7 uint64
+	var x8 uint64
+	x8, x7 = bits.Mul64(x4, 0xfffffffe00000000)
+	var x9 uint64
+	var x10 uint64
+	x10, x9 = bits.Mul64(x4, 0xffffffff00000000)
+	var x11 uint64
+	var x12 uint64
+	x12, x11 = bits.Mul64(x4, 0xffffffff00000001)
+	var x13 uint64
+	var x14 uint64
+	x13, x14 = bits.Add64(x12, x9, uint64(0x0))
+	var x15 uint64
+	var x16 uint64
+	x15, x16 = bits.Add64(x10, x7, uint64(p224Uint1(x14)))
+	var x17 uint64
+	var x18 uint64
+	x17, x18 = bits.Add64(x8, x5, uint64(p224Uint1(x16)))
+	var x19 uint64
+	_, x19 = bits.Mul64(x11, 0xffffffffffffffff)
+	var x21 uint64
+	var x22 uint64
+	x22, x21 = bits.Mul64(x19, 0xffffffff)
+	var x23 uint64
+	var x24 uint64
+	x24, x23 = bits.Mul64(x19, 0xffffffffffffffff)
+	var x25 uint64
+	var x26 uint64
+	x26, x25 = bits.Mul64(x19, 0xffffffff00000000)
+	var x27 uint64
+	var x28 uint64
+	x27, x28 = bits.Add64(x26, x23, uint64(0x0))
+	var x29 uint64
+	var x30 uint64
+	x29, x30 = bits.Add64(x24, x21, uint64(p224Uint1(x28)))
+	var x32 uint64
+	_, x32 = bits.Add64(x11, x19, uint64(0x0))
+	var x33 uint64
+	var x34 uint64
+	x33, x34 = bits.Add64(x13, x25, uint64(p224Uint1(x32)))
+	var x35 uint64
+	var x36 uint64
+	x35, x36 = bits.Add64(x15, x27, uint64(p224Uint1(x34)))
+	var x37 uint64
+	var x38 uint64
+	x37, x38 = bits.Add64(x17, x29, uint64(p224Uint1(x36)))
+	var x39 uint64
+	var x40 uint64
+	x40, x39 = bits.Mul64(x1, 0xffffffff)
+	var x41 uint64
+	var x42 uint64
+	x42, x41 = bits.Mul64(x1, 0xfffffffe00000000)
+	var x43 uint64
+	var x44 uint64
+	x44, x43 = bits.Mul64(x1, 0xffffffff00000000)
+	var x45 uint64
+	var x46 uint64
+	x46, x45 = bits.Mul64(x1, 0xffffffff00000001)
+	var x47 uint64
+	var x48 uint64
+	x47, x48 = bits.Add64(x46, x43, uint64(0x0))
+	var x49 uint64
+	var x50 uint64
+	x49, x50 = bits.Add64(x44, x41, uint64(p224Uint1(x48)))
+	var x51 uint64
+	var x52 uint64
+	x51, x52 = bits.Add64(x42, x39, uint64(p224Uint1(x50)))
+	var x53 uint64
+	var x54 uint64
+	x53, x54 = bits.Add64(x33, x45, uint64(0x0))
+	var x55 uint64
+	var x56 uint64
+	x55, x56 = bits.Add64(x35, x47, uint64(p224Uint1(x54)))
+	var x57 uint64
+	var x58 uint64
+	x57, x58 = bits.Add64(x37, x49, uint64(p224Uint1(x56)))
+	var x59 uint64
+	var x60 uint64
+	x59, x60 = bits.Add64(((uint64(p224Uint1(x38)) + (uint64(p224Uint1(x18)) + x6)) + (uint64(p224Uint1(x30)) + x22)), x51, uint64(p224Uint1(x58)))
+	var x61 uint64
+	_, x61 = bits.Mul64(x53, 0xffffffffffffffff)
+	var x63 uint64
+	var x64 uint64
+	x64, x63 = bits.Mul64(x61, 0xffffffff)
+	var x65 uint64
+	var x66 uint64
+	x66, x65 = bits.Mul64(x61, 0xffffffffffffffff)
+	var x67 uint64
+	var x68 uint64
+	x68, x67 = bits.Mul64(x61, 0xffffffff00000000)
+	var x69 uint64
+	var x70 uint64
+	x69, x70 = bits.Add64(x68, x65, uint64(0x0))
+	var x71 uint64
+	var x72 uint64
+	x71, x72 = bits.Add64(x66, x63, uint64(p224Uint1(x70)))
+	var x74 uint64
+	_, x74 = bits.Add64(x53, x61, uint64(0x0))
+	var x75 uint64
+	var x76 uint64
+	x75, x76 = bits.Add64(x55, x67, uint64(p224Uint1(x74)))
+	var x77 uint64
+	var x78 uint64
+	x77, x78 = bits.Add64(x57, x69, uint64(p224Uint1(x76)))
+	var x79 uint64
+	var x80 uint64
+	x79, x80 = bits.Add64(x59, x71, uint64(p224Uint1(x78)))
+	var x81 uint64
+	var x82 uint64
+	x82, x81 = bits.Mul64(x2, 0xffffffff)
+	var x83 uint64
+	var x84 uint64
+	x84, x83 = bits.Mul64(x2, 0xfffffffe00000000)
+	var x85 uint64
+	var x86 uint64
+	x86, x85 = bits.Mul64(x2, 0xffffffff00000000)
+	var x87 uint64
+	var x88 uint64
+	x88, x87 = bits.Mul64(x2, 0xffffffff00000001)
+	var x89 uint64
+	var x90 uint64
+	x89, x90 = bits.Add64(x88, x85, uint64(0x0))
+	var x91 uint64
+	var x92 uint64
+	x91, x92 = bits.Add64(x86, x83, uint64(p224Uint1(x90)))
+	var x93 uint64
+	var x94 uint64
+	x93, x94 = bits.Add64(x84, x81, uint64(p224Uint1(x92)))
+	var x95 uint64
+	var x96 uint64
+	x95, x96 = bits.Add64(x75, x87, uint64(0x0))
+	var x97 uint64
+	var x98 uint64
+	x97, x98 = bits.Add64(x77, x89, uint64(p224Uint1(x96)))
+	var x99 uint64
+	var x100 uint64
+	x99, x100 = bits.Add64(x79, x91, uint64(p224Uint1(x98)))
+	var x101 uint64
+	var x102 uint64
+	x101, x102 = bits.Add64(((uint64(p224Uint1(x80)) + (uint64(p224Uint1(x60)) + (uint64(p224Uint1(x52)) + x40))) + (uint64(p224Uint1(x72)) + x64)), x93, uint64(p224Uint1(x100)))
+	var x103 uint64
+	_, x103 = bits.Mul64(x95, 0xffffffffffffffff)
+	var x105 uint64
+	var x106 uint64
+	x106, x105 = bits.Mul64(x103, 0xffffffff)
+	var x107 uint64
+	var x108 uint64
+	x108, x107 = bits.Mul64(x103, 0xffffffffffffffff)
+	var x109 uint64
+	var x110 uint64
+	x110, x109 = bits.Mul64(x103, 0xffffffff00000000)
+	var x111 uint64
+	var x112 uint64
+	x111, x112 = bits.Add64(x110, x107, uint64(0x0))
+	var x113 uint64
+	var x114 uint64
+	x113, x114 = bits.Add64(x108, x105, uint64(p224Uint1(x112)))
+	var x116 uint64
+	_, x116 = bits.Add64(x95, x103, uint64(0x0))
+	var x117 uint64
+	var x118 uint64
+	x117, x118 = bits.Add64(x97, x109, uint64(p224Uint1(x116)))
+	var x119 uint64
+	var x120 uint64
+	x119, x120 = bits.Add64(x99, x111, uint64(p224Uint1(x118)))
+	var x121 uint64
+	var x122 uint64
+	x121, x122 = bits.Add64(x101, x113, uint64(p224Uint1(x120)))
+	var x123 uint64
+	var x124 uint64
+	x124, x123 = bits.Mul64(x3, 0xffffffff)
+	var x125 uint64
+	var x126 uint64
+	x126, x125 = bits.Mul64(x3, 0xfffffffe00000000)
+	var x127 uint64
+	var x128 uint64
+	x128, x127 = bits.Mul64(x3, 0xffffffff00000000)
+	var x129 uint64
+	var x130 uint64
+	x130, x129 = bits.Mul64(x3, 0xffffffff00000001)
+	var x131 uint64
+	var x132 uint64
+	x131, x132 = bits.Add64(x130, x127, uint64(0x0))
+	var x133 uint64
+	var x134 uint64
+	x133, x134 = bits.Add64(x128, x125, uint64(p224Uint1(x132)))
+	var x135 uint64
+	var x136 uint64
+	x135, x136 = bits.Add64(x126, x123, uint64(p224Uint1(x134)))
+	var x137 uint64
+	var x138 uint64
+	x137, x138 = bits.Add64(x117, x129, uint64(0x0))
+	var x139 uint64
+	var x140 uint64
+	x139, x140 = bits.Add64(x119, x131, uint64(p224Uint1(x138)))
+	var x141 uint64
+	var x142 uint64
+	x141, x142 = bits.Add64(x121, x133, uint64(p224Uint1(x140)))
+	var x143 uint64
+	var x144 uint64
+	x143, x144 = bits.Add64(((uint64(p224Uint1(x122)) + (uint64(p224Uint1(x102)) + (uint64(p224Uint1(x94)) + x82))) + (uint64(p224Uint1(x114)) + x106)), x135, uint64(p224Uint1(x142)))
+	var x145 uint64
+	_, x145 = bits.Mul64(x137, 0xffffffffffffffff)
+	var x147 uint64
+	var x148 uint64
+	x148, x147 = bits.Mul64(x145, 0xffffffff)
+	var x149 uint64
+	var x150 uint64
+	x150, x149 = bits.Mul64(x145, 0xffffffffffffffff)
+	var x151 uint64
+	var x152 uint64
+	x152, x151 = bits.Mul64(x145, 0xffffffff00000000)
+	var x153 uint64
+	var x154 uint64
+	x153, x154 = bits.Add64(x152, x149, uint64(0x0))
+	var x155 uint64
+	var x156 uint64
+	x155, x156 = bits.Add64(x150, x147, uint64(p224Uint1(x154)))
+	var x158 uint64
+	_, x158 = bits.Add64(x137, x145, uint64(0x0))
+	var x159 uint64
+	var x160 uint64
+	x159, x160 = bits.Add64(x139, x151, uint64(p224Uint1(x158)))
+	var x161 uint64
+	var x162 uint64
+	x161, x162 = bits.Add64(x141, x153, uint64(p224Uint1(x160)))
+	var x163 uint64
+	var x164 uint64
+	x163, x164 = bits.Add64(x143, x155, uint64(p224Uint1(x162)))
+	x165 := ((uint64(p224Uint1(x164)) + (uint64(p224Uint1(x144)) + (uint64(p224Uint1(x136)) + x124))) + (uint64(p224Uint1(x156)) + x148))
+	var x166 uint64
+	var x167 uint64
+	x166, x167 = bits.Sub64(x159, uint64(0x1), uint64(0x0))
+	var x168 uint64
+	var x169 uint64
+	x168, x169 = bits.Sub64(x161, 0xffffffff00000000, uint64(p224Uint1(x167)))
+	var x170 uint64
+	var x171 uint64
+	x170, x171 = bits.Sub64(x163, 0xffffffffffffffff, uint64(p224Uint1(x169)))
+	var x172 uint64
+	var x173 uint64
+	x172, x173 = bits.Sub64(x165, 0xffffffff, uint64(p224Uint1(x171)))
+	var x175 uint64
+	_, x175 = bits.Sub64(uint64(0x0), uint64(0x0), uint64(p224Uint1(x173)))
+	var x176 uint64
+	p224CmovznzU64(&x176, p224Uint1(x175), x166, x159)
+	var x177 uint64
+	p224CmovznzU64(&x177, p224Uint1(x175), x168, x161)
+	var x178 uint64
+	p224CmovznzU64(&x178, p224Uint1(x175), x170, x163)
+	var x179 uint64
+	p224CmovznzU64(&x179, p224Uint1(x175), x172, x165)
+	out1[0] = x176
+	out1[1] = x177
+	out1[2] = x178
+	out1[3] = x179
+}
+
+// p224Selectznz is a multi-limb conditional select.
+//
+// Postconditions:
+//
+//	eval out1 = (if arg1 = 0 then eval arg2 else eval arg3)
+//
+// Input Bounds:
+//
+//	arg1: [0x0 ~> 0x1]
+//	arg2: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
+//	arg3: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
+//
+// Output Bounds:
+//
+//	out1: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
+func p224Selectznz(out1 *[4]uint64, arg1 p224Uint1, arg2 *[4]uint64, arg3 *[4]uint64) {
+	var x1 uint64
+	p224CmovznzU64(&x1, arg1, arg2[0], arg3[0])
+	var x2 uint64
+	p224CmovznzU64(&x2, arg1, arg2[1], arg3[1])
+	var x3 uint64
+	p224CmovznzU64(&x3, arg1, arg2[2], arg3[2])
+	var x4 uint64
+	p224CmovznzU64(&x4, arg1, arg2[3], arg3[3])
+	out1[0] = x1
+	out1[1] = x2
+	out1[2] = x3
+	out1[3] = x4
+}
+
+// p224ToBytes serializes a field element NOT in the Montgomery domain to bytes in little-endian order.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//
+// Postconditions:
+//
+//	out1 = map (λ x, ⌊((eval arg1 mod m) mod 2^(8 * (x + 1))) / 2^(8 * x)⌋) [0..27]
+//
+// Input Bounds:
+//
+//	arg1: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffff]]
+//
+// Output Bounds:
+//
+//	out1: [[0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff]]
+func p224ToBytes(out1 *[28]uint8, arg1 *[4]uint64) {
+	x1 := arg1[3]
+	x2 := arg1[2]
+	x3 := arg1[1]
+	x4 := arg1[0]
+	x5 := (uint8(x4) & 0xff)
+	x6 := (x4 >> 8)
+	x7 := (uint8(x6) & 0xff)
+	x8 := (x6 >> 8)
+	x9 := (uint8(x8) & 0xff)
+	x10 := (x8 >> 8)
+	x11 := (uint8(x10) & 0xff)
+	x12 := (x10 >> 8)
+	x13 := (uint8(x12) & 0xff)
+	x14 := (x12 >> 8)
+	x15 := (uint8(x14) & 0xff)
+	x16 := (x14 >> 8)
+	x17 := (uint8(x16) & 0xff)
+	x18 := uint8((x16 >> 8))
+	x19 := (uint8(x3) & 0xff)
+	x20 := (x3 >> 8)
+	x21 := (uint8(x20) & 0xff)
+	x22 := (x20 >> 8)
+	x23 := (uint8(x22) & 0xff)
+	x24 := (x22 >> 8)
+	x25 := (uint8(x24) & 0xff)
+	x26 := (x24 >> 8)
+	x27 := (uint8(x26) & 0xff)
+	x28 := (x26 >> 8)
+	x29 := (uint8(x28) & 0xff)
+	x30 := (x28 >> 8)
+	x31 := (uint8(x30) & 0xff)
+	x32 := uint8((x30 >> 8))
+	x33 := (uint8(x2) & 0xff)
+	x34 := (x2 >> 8)
+	x35 := (uint8(x34) & 0xff)
+	x36 := (x34 >> 8)
+	x37 := (uint8(x36) & 0xff)
+	x38 := (x36 >> 8)
+	x39 := (uint8(x38) & 0xff)
+	x40 := (x38 >> 8)
+	x41 := (uint8(x40) & 0xff)
+	x42 := (x40 >> 8)
+	x43 := (uint8(x42) & 0xff)
+	x44 := (x42 >> 8)
+	x45 := (uint8(x44) & 0xff)
+	x46 := uint8((x44 >> 8))
+	x47 := (uint8(x1) & 0xff)
+	x48 := (x1 >> 8)
+	x49 := (uint8(x48) & 0xff)
+	x50 := (x48 >> 8)
+	x51 := (uint8(x50) & 0xff)
+	x52 := uint8((x50 >> 8))
+	out1[0] = x5
+	out1[1] = x7
+	out1[2] = x9
+	out1[3] = x11
+	out1[4] = x13
+	out1[5] = x15
+	out1[6] = x17
+	out1[7] = x18
+	out1[8] = x19
+	out1[9] = x21
+	out1[10] = x23
+	out1[11] = x25
+	out1[12] = x27
+	out1[13] = x29
+	out1[14] = x31
+	out1[15] = x32
+	out1[16] = x33
+	out1[17] = x35
+	out1[18] = x37
+	out1[19] = x39
+	out1[20] = x41
+	out1[21] = x43
+	out1[22] = x45
+	out1[23] = x46
+	out1[24] = x47
+	out1[25] = x49
+	out1[26] = x51
+	out1[27] = x52
+}
+
+// p224FromBytes deserializes a field element NOT in the Montgomery domain from bytes in little-endian order.
+//
+// Preconditions:
+//
+//	0 ≤ bytes_eval arg1 < m
+//
+// Postconditions:
+//
+//	eval out1 mod m = bytes_eval arg1 mod m
+//	0 ≤ eval out1 < m
+//
+// Input Bounds:
+//
+//	arg1: [[0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff]]
+//
+// Output Bounds:
+//
+//	out1: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffff]]
+func p224FromBytes(out1 *[4]uint64, arg1 *[28]uint8) {
+	x1 := (uint64(arg1[27]) << 24)
+	x2 := (uint64(arg1[26]) << 16)
+	x3 := (uint64(arg1[25]) << 8)
+	x4 := arg1[24]
+	x5 := (uint64(arg1[23]) << 56)
+	x6 := (uint64(arg1[22]) << 48)
+	x7 := (uint64(arg1[21]) << 40)
+	x8 := (uint64(arg1[20]) << 32)
+	x9 := (uint64(arg1[19]) << 24)
+	x10 := (uint64(arg1[18]) << 16)
+	x11 := (uint64(arg1[17]) << 8)
+	x12 := arg1[16]
+	x13 := (uint64(arg1[15]) << 56)
+	x14 := (uint64(arg1[14]) << 48)
+	x15 := (uint64(arg1[13]) << 40)
+	x16 := (uint64(arg1[12]) << 32)
+	x17 := (uint64(arg1[11]) << 24)
+	x18 := (uint64(arg1[10]) << 16)
+	x19 := (uint64(arg1[9]) << 8)
+	x20 := arg1[8]
+	x21 := (uint64(arg1[7]) << 56)
+	x22 := (uint64(arg1[6]) << 48)
+	x23 := (uint64(arg1[5]) << 40)
+	x24 := (uint64(arg1[4]) << 32)
+	x25 := (uint64(arg1[3]) << 24)
+	x26 := (uint64(arg1[2]) << 16)
+	x27 := (uint64(arg1[1]) << 8)
+	x28 := arg1[0]
+	x29 := (x27 + uint64(x28))
+	x30 := (x26 + x29)
+	x31 := (x25 + x30)
+	x32 := (x24 + x31)
+	x33 := (x23 + x32)
+	x34 := (x22 + x33)
+	x35 := (x21 + x34)
+	x36 := (x19 + uint64(x20))
+	x37 := (x18 + x36)
+	x38 := (x17 + x37)
+	x39 := (x16 + x38)
+	x40 := (x15 + x39)
+	x41 := (x14 + x40)
+	x42 := (x13 + x41)
+	x43 := (x11 + uint64(x12))
+	x44 := (x10 + x43)
+	x45 := (x9 + x44)
+	x46 := (x8 + x45)
+	x47 := (x7 + x46)
+	x48 := (x6 + x47)
+	x49 := (x5 + x48)
+	x50 := (x3 + uint64(x4))
+	x51 := (x2 + x50)
+	x52 := (x1 + x51)
+	out1[0] = x35
+	out1[1] = x42
+	out1[2] = x49
+	out1[3] = x52
+}
diff --git a/contrib/go/_std_1.18/src/crypto/elliptic/internal/fiat/p224_invert.go b/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p224_invert.go
index 4163ed0c67..4163ed0c67 100644
--- a/contrib/go/_std_1.18/src/crypto/elliptic/internal/fiat/p224_invert.go
+++ b/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p224_invert.go
diff --git a/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p256.go b/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p256.go
new file mode 100644
index 0000000000..dfdd0a7c69
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p256.go
@@ -0,0 +1,135 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Code generated by generate.go. DO NOT EDIT.
+
+package fiat
+
+import (
+	"crypto/subtle"
+	"errors"
+)
+
+// P256Element is an integer modulo 2^256 - 2^224 + 2^192 + 2^96 - 1.
+//
+// The zero value is a valid zero element.
+type P256Element struct {
+	// Values are represented internally always in the Montgomery domain, and
+	// converted in Bytes and SetBytes.
+	x p256MontgomeryDomainFieldElement
+}
+
+const p256ElementLen = 32
+
+type p256UntypedFieldElement = [4]uint64
+
+// One sets e = 1, and returns e.
+func (e *P256Element) One() *P256Element {
+	p256SetOne(&e.x)
+	return e
+}
+
+// Equal returns 1 if e == t, and zero otherwise.
+func (e *P256Element) Equal(t *P256Element) int {
+	eBytes := e.Bytes()
+	tBytes := t.Bytes()
+	return subtle.ConstantTimeCompare(eBytes, tBytes)
+}
+
+var p256ZeroEncoding = new(P256Element).Bytes()
+
+// IsZero returns 1 if e == 0, and zero otherwise.
+func (e *P256Element) IsZero() int {
+	eBytes := e.Bytes()
+	return subtle.ConstantTimeCompare(eBytes, p256ZeroEncoding)
+}
+
+// Set sets e = t, and returns e.
+func (e *P256Element) Set(t *P256Element) *P256Element {
+	e.x = t.x
+	return e
+}
+
+// Bytes returns the 32-byte big-endian encoding of e.
+func (e *P256Element) Bytes() []byte {
+	// This function is outlined to make the allocations inline in the caller
+	// rather than happen on the heap.
+	var out [p256ElementLen]byte
+	return e.bytes(&out)
+}
+
+func (e *P256Element) bytes(out *[p256ElementLen]byte) []byte {
+	var tmp p256NonMontgomeryDomainFieldElement
+	p256FromMontgomery(&tmp, &e.x)
+	p256ToBytes(out, (*p256UntypedFieldElement)(&tmp))
+	p256InvertEndianness(out[:])
+	return out[:]
+}
+
+// p256MinusOneEncoding is the encoding of -1 mod p, so p - 1, the
+// highest canonical encoding. It is used by SetBytes to check for non-canonical
+// encodings such as p + k, 2p + k, etc.
+var p256MinusOneEncoding = new(P256Element).Sub(
+	new(P256Element), new(P256Element).One()).Bytes()
+
+// SetBytes sets e = v, where v is a big-endian 32-byte encoding, and returns e.
+// If v is not 32 bytes or it encodes a value higher than 2^256 - 2^224 + 2^192 + 2^96 - 1,
+// SetBytes returns nil and an error, and e is unchanged.
+func (e *P256Element) SetBytes(v []byte) (*P256Element, error) {
+	if len(v) != p256ElementLen {
+		return nil, errors.New("invalid P256Element encoding")
+	}
+	for i := range v {
+		if v[i] < p256MinusOneEncoding[i] {
+			break
+		}
+		if v[i] > p256MinusOneEncoding[i] {
+			return nil, errors.New("invalid P256Element encoding")
+		}
+	}
+	var in [p256ElementLen]byte
+	copy(in[:], v)
+	p256InvertEndianness(in[:])
+	var tmp p256NonMontgomeryDomainFieldElement
+	p256FromBytes((*p256UntypedFieldElement)(&tmp), &in)
+	p256ToMontgomery(&e.x, &tmp)
+	return e, nil
+}
+
+// Add sets e = t1 + t2, and returns e.
+func (e *P256Element) Add(t1, t2 *P256Element) *P256Element {
+	p256Add(&e.x, &t1.x, &t2.x)
+	return e
+}
+
+// Sub sets e = t1 - t2, and returns e.
+func (e *P256Element) Sub(t1, t2 *P256Element) *P256Element {
+	p256Sub(&e.x, &t1.x, &t2.x)
+	return e
+}
+
+// Mul sets e = t1 * t2, and returns e.
+func (e *P256Element) Mul(t1, t2 *P256Element) *P256Element {
+	p256Mul(&e.x, &t1.x, &t2.x)
+	return e
+}
+
+// Square sets e = t * t, and returns e.
+func (e *P256Element) Square(t *P256Element) *P256Element {
+	p256Square(&e.x, &t.x)
+	return e
+}
+
+// Select sets v to a if cond == 1, and to b if cond == 0.
+func (v *P256Element) Select(a, b *P256Element, cond int) *P256Element {
+	p256Selectznz((*p256UntypedFieldElement)(&v.x), p256Uint1(cond),
+		(*p256UntypedFieldElement)(&b.x), (*p256UntypedFieldElement)(&a.x))
+	return v
+}
+
+func p256InvertEndianness(v []byte) {
+	for i := 0; i < len(v)/2; i++ {
+		v[i], v[len(v)-1-i] = v[len(v)-1-i], v[i]
+	}
+}
diff --git a/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p256_fiat64.go b/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p256_fiat64.go
new file mode 100644
index 0000000000..75352d5d26
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p256_fiat64.go
@@ -0,0 +1,1400 @@
+// Code generated by Fiat Cryptography. DO NOT EDIT.
+//
+// Autogenerated: word_by_word_montgomery --lang Go --no-wide-int --cmovznz-by-mul --relax-primitive-carry-to-bitwidth 32,64 --internal-static --public-function-case camelCase --public-type-case camelCase --private-function-case camelCase --private-type-case camelCase --doc-text-before-function-name '' --doc-newline-before-package-declaration --doc-prepend-header 'Code generated by Fiat Cryptography. DO NOT EDIT.' --package-name fiat --no-prefix-fiat p256 64 '2^256 - 2^224 + 2^192 + 2^96 - 1' mul square add sub one from_montgomery to_montgomery selectznz to_bytes from_bytes
+//
+// curve description: p256
+//
+// machine_wordsize = 64 (from "64")
+//
+// requested operations: mul, square, add, sub, one, from_montgomery, to_montgomery, selectznz, to_bytes, from_bytes
+//
+// m = 0xffffffff00000001000000000000000000000000ffffffffffffffffffffffff (from "2^256 - 2^224 + 2^192 + 2^96 - 1")
+//
+//
+//
+// NOTE: In addition to the bounds specified above each function, all
+//
+//   functions synthesized for this Montgomery arithmetic require the
+//
+//   input to be strictly less than the prime modulus (m), and also
+//
+//   require the input to be in the unique saturated representation.
+//
+//   All functions also ensure that these two properties are true of
+//
+//   return values.
+//
+//
+//
+// Computed values:
+//
+//   eval z = z[0] + (z[1] << 64) + (z[2] << 128) + (z[3] << 192)
+//
+//   bytes_eval z = z[0] + (z[1] << 8) + (z[2] << 16) + (z[3] << 24) + (z[4] << 32) + (z[5] << 40) + (z[6] << 48) + (z[7] << 56) + (z[8] << 64) + (z[9] << 72) + (z[10] << 80) + (z[11] << 88) + (z[12] << 96) + (z[13] << 104) + (z[14] << 112) + (z[15] << 120) + (z[16] << 128) + (z[17] << 136) + (z[18] << 144) + (z[19] << 152) + (z[20] << 160) + (z[21] << 168) + (z[22] << 176) + (z[23] << 184) + (z[24] << 192) + (z[25] << 200) + (z[26] << 208) + (z[27] << 216) + (z[28] << 224) + (z[29] << 232) + (z[30] << 240) + (z[31] << 248)
+//
+//   twos_complement_eval z = let x1 := z[0] + (z[1] << 64) + (z[2] << 128) + (z[3] << 192) in
+//
+//                            if x1 & (2^256-1) < 2^255 then x1 & (2^256-1) else (x1 & (2^256-1)) - 2^256
+
+package fiat
+
+import "math/bits"
+
+type p256Uint1 uint64 // We use uint64 instead of a more narrow type for performance reasons; see https://github.com/mit-plv/fiat-crypto/pull/1006#issuecomment-892625927
+type p256Int1 int64   // We use uint64 instead of a more narrow type for performance reasons; see https://github.com/mit-plv/fiat-crypto/pull/1006#issuecomment-892625927
+
+// The type p256MontgomeryDomainFieldElement is a field element in the Montgomery domain.
+//
+// Bounds: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
+type p256MontgomeryDomainFieldElement [4]uint64
+
+// The type p256NonMontgomeryDomainFieldElement is a field element NOT in the Montgomery domain.
+//
+// Bounds: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
+type p256NonMontgomeryDomainFieldElement [4]uint64
+
+// p256CmovznzU64 is a single-word conditional move.
+//
+// Postconditions:
+//
+//	out1 = (if arg1 = 0 then arg2 else arg3)
+//
+// Input Bounds:
+//
+//	arg1: [0x0 ~> 0x1]
+//	arg2: [0x0 ~> 0xffffffffffffffff]
+//	arg3: [0x0 ~> 0xffffffffffffffff]
+//
+// Output Bounds:
+//
+//	out1: [0x0 ~> 0xffffffffffffffff]
+func p256CmovznzU64(out1 *uint64, arg1 p256Uint1, arg2 uint64, arg3 uint64) {
+	x1 := (uint64(arg1) * 0xffffffffffffffff)
+	x2 := ((x1 & arg3) | ((^x1) & arg2))
+	*out1 = x2
+}
+
+// p256Mul multiplies two field elements in the Montgomery domain.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//	0 ≤ eval arg2 < m
+//
+// Postconditions:
+//
+//	eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) * eval (from_montgomery arg2)) mod m
+//	0 ≤ eval out1 < m
+func p256Mul(out1 *p256MontgomeryDomainFieldElement, arg1 *p256MontgomeryDomainFieldElement, arg2 *p256MontgomeryDomainFieldElement) {
+	x1 := arg1[1]
+	x2 := arg1[2]
+	x3 := arg1[3]
+	x4 := arg1[0]
+	var x5 uint64
+	var x6 uint64
+	x6, x5 = bits.Mul64(x4, arg2[3])
+	var x7 uint64
+	var x8 uint64
+	x8, x7 = bits.Mul64(x4, arg2[2])
+	var x9 uint64
+	var x10 uint64
+	x10, x9 = bits.Mul64(x4, arg2[1])
+	var x11 uint64
+	var x12 uint64
+	x12, x11 = bits.Mul64(x4, arg2[0])
+	var x13 uint64
+	var x14 uint64
+	x13, x14 = bits.Add64(x12, x9, uint64(0x0))
+	var x15 uint64
+	var x16 uint64
+	x15, x16 = bits.Add64(x10, x7, uint64(p256Uint1(x14)))
+	var x17 uint64
+	var x18 uint64
+	x17, x18 = bits.Add64(x8, x5, uint64(p256Uint1(x16)))
+	x19 := (uint64(p256Uint1(x18)) + x6)
+	var x20 uint64
+	var x21 uint64
+	x21, x20 = bits.Mul64(x11, 0xffffffff00000001)
+	var x22 uint64
+	var x23 uint64
+	x23, x22 = bits.Mul64(x11, 0xffffffff)
+	var x24 uint64
+	var x25 uint64
+	x25, x24 = bits.Mul64(x11, 0xffffffffffffffff)
+	var x26 uint64
+	var x27 uint64
+	x26, x27 = bits.Add64(x25, x22, uint64(0x0))
+	x28 := (uint64(p256Uint1(x27)) + x23)
+	var x30 uint64
+	_, x30 = bits.Add64(x11, x24, uint64(0x0))
+	var x31 uint64
+	var x32 uint64
+	x31, x32 = bits.Add64(x13, x26, uint64(p256Uint1(x30)))
+	var x33 uint64
+	var x34 uint64
+	x33, x34 = bits.Add64(x15, x28, uint64(p256Uint1(x32)))
+	var x35 uint64
+	var x36 uint64
+	x35, x36 = bits.Add64(x17, x20, uint64(p256Uint1(x34)))
+	var x37 uint64
+	var x38 uint64
+	x37, x38 = bits.Add64(x19, x21, uint64(p256Uint1(x36)))
+	var x39 uint64
+	var x40 uint64
+	x40, x39 = bits.Mul64(x1, arg2[3])
+	var x41 uint64
+	var x42 uint64
+	x42, x41 = bits.Mul64(x1, arg2[2])
+	var x43 uint64
+	var x44 uint64
+	x44, x43 = bits.Mul64(x1, arg2[1])
+	var x45 uint64
+	var x46 uint64
+	x46, x45 = bits.Mul64(x1, arg2[0])
+	var x47 uint64
+	var x48 uint64
+	x47, x48 = bits.Add64(x46, x43, uint64(0x0))
+	var x49 uint64
+	var x50 uint64
+	x49, x50 = bits.Add64(x44, x41, uint64(p256Uint1(x48)))
+	var x51 uint64
+	var x52 uint64
+	x51, x52 = bits.Add64(x42, x39, uint64(p256Uint1(x50)))
+	x53 := (uint64(p256Uint1(x52)) + x40)
+	var x54 uint64
+	var x55 uint64
+	x54, x55 = bits.Add64(x31, x45, uint64(0x0))
+	var x56 uint64
+	var x57 uint64
+	x56, x57 = bits.Add64(x33, x47, uint64(p256Uint1(x55)))
+	var x58 uint64
+	var x59 uint64
+	x58, x59 = bits.Add64(x35, x49, uint64(p256Uint1(x57)))
+	var x60 uint64
+	var x61 uint64
+	x60, x61 = bits.Add64(x37, x51, uint64(p256Uint1(x59)))
+	var x62 uint64
+	var x63 uint64
+	x62, x63 = bits.Add64(uint64(p256Uint1(x38)), x53, uint64(p256Uint1(x61)))
+	var x64 uint64
+	var x65 uint64
+	x65, x64 = bits.Mul64(x54, 0xffffffff00000001)
+	var x66 uint64
+	var x67 uint64
+	x67, x66 = bits.Mul64(x54, 0xffffffff)
+	var x68 uint64
+	var x69 uint64
+	x69, x68 = bits.Mul64(x54, 0xffffffffffffffff)
+	var x70 uint64
+	var x71 uint64
+	x70, x71 = bits.Add64(x69, x66, uint64(0x0))
+	x72 := (uint64(p256Uint1(x71)) + x67)
+	var x74 uint64
+	_, x74 = bits.Add64(x54, x68, uint64(0x0))
+	var x75 uint64
+	var x76 uint64
+	x75, x76 = bits.Add64(x56, x70, uint64(p256Uint1(x74)))
+	var x77 uint64
+	var x78 uint64
+	x77, x78 = bits.Add64(x58, x72, uint64(p256Uint1(x76)))
+	var x79 uint64
+	var x80 uint64
+	x79, x80 = bits.Add64(x60, x64, uint64(p256Uint1(x78)))
+	var x81 uint64
+	var x82 uint64
+	x81, x82 = bits.Add64(x62, x65, uint64(p256Uint1(x80)))
+	x83 := (uint64(p256Uint1(x82)) + uint64(p256Uint1(x63)))
+	var x84 uint64
+	var x85 uint64
+	x85, x84 = bits.Mul64(x2, arg2[3])
+	var x86 uint64
+	var x87 uint64
+	x87, x86 = bits.Mul64(x2, arg2[2])
+	var x88 uint64
+	var x89 uint64
+	x89, x88 = bits.Mul64(x2, arg2[1])
+	var x90 uint64
+	var x91 uint64
+	x91, x90 = bits.Mul64(x2, arg2[0])
+	var x92 uint64
+	var x93 uint64
+	x92, x93 = bits.Add64(x91, x88, uint64(0x0))
+	var x94 uint64
+	var x95 uint64
+	x94, x95 = bits.Add64(x89, x86, uint64(p256Uint1(x93)))
+	var x96 uint64
+	var x97 uint64
+	x96, x97 = bits.Add64(x87, x84, uint64(p256Uint1(x95)))
+	x98 := (uint64(p256Uint1(x97)) + x85)
+	var x99 uint64
+	var x100 uint64
+	x99, x100 = bits.Add64(x75, x90, uint64(0x0))
+	var x101 uint64
+	var x102 uint64
+	x101, x102 = bits.Add64(x77, x92, uint64(p256Uint1(x100)))
+	var x103 uint64
+	var x104 uint64
+	x103, x104 = bits.Add64(x79, x94, uint64(p256Uint1(x102)))
+	var x105 uint64
+	var x106 uint64
+	x105, x106 = bits.Add64(x81, x96, uint64(p256Uint1(x104)))
+	var x107 uint64
+	var x108 uint64
+	x107, x108 = bits.Add64(x83, x98, uint64(p256Uint1(x106)))
+	var x109 uint64
+	var x110 uint64
+	x110, x109 = bits.Mul64(x99, 0xffffffff00000001)
+	var x111 uint64
+	var x112 uint64
+	x112, x111 = bits.Mul64(x99, 0xffffffff)
+	var x113 uint64
+	var x114 uint64
+	x114, x113 = bits.Mul64(x99, 0xffffffffffffffff)
+	var x115 uint64
+	var x116 uint64
+	x115, x116 = bits.Add64(x114, x111, uint64(0x0))
+	x117 := (uint64(p256Uint1(x116)) + x112)
+	var x119 uint64
+	_, x119 = bits.Add64(x99, x113, uint64(0x0))
+	var x120 uint64
+	var x121 uint64
+	x120, x121 = bits.Add64(x101, x115, uint64(p256Uint1(x119)))
+	var x122 uint64
+	var x123 uint64
+	x122, x123 = bits.Add64(x103, x117, uint64(p256Uint1(x121)))
+	var x124 uint64
+	var x125 uint64
+	x124, x125 = bits.Add64(x105, x109, uint64(p256Uint1(x123)))
+	var x126 uint64
+	var x127 uint64
+	x126, x127 = bits.Add64(x107, x110, uint64(p256Uint1(x125)))
+	x128 := (uint64(p256Uint1(x127)) + uint64(p256Uint1(x108)))
+	var x129 uint64
+	var x130 uint64
+	x130, x129 = bits.Mul64(x3, arg2[3])
+	var x131 uint64
+	var x132 uint64
+	x132, x131 = bits.Mul64(x3, arg2[2])
+	var x133 uint64
+	var x134 uint64
+	x134, x133 = bits.Mul64(x3, arg2[1])
+	var x135 uint64
+	var x136 uint64
+	x136, x135 = bits.Mul64(x3, arg2[0])
+	var x137 uint64
+	var x138 uint64
+	x137, x138 = bits.Add64(x136, x133, uint64(0x0))
+	var x139 uint64
+	var x140 uint64
+	x139, x140 = bits.Add64(x134, x131, uint64(p256Uint1(x138)))
+	var x141 uint64
+	var x142 uint64
+	x141, x142 = bits.Add64(x132, x129, uint64(p256Uint1(x140)))
+	x143 := (uint64(p256Uint1(x142)) + x130)
+	var x144 uint64
+	var x145 uint64
+	x144, x145 = bits.Add64(x120, x135, uint64(0x0))
+	var x146 uint64
+	var x147 uint64
+	x146, x147 = bits.Add64(x122, x137, uint64(p256Uint1(x145)))
+	var x148 uint64
+	var x149 uint64
+	x148, x149 = bits.Add64(x124, x139, uint64(p256Uint1(x147)))
+	var x150 uint64
+	var x151 uint64
+	x150, x151 = bits.Add64(x126, x141, uint64(p256Uint1(x149)))
+	var x152 uint64
+	var x153 uint64
+	x152, x153 = bits.Add64(x128, x143, uint64(p256Uint1(x151)))
+	var x154 uint64
+	var x155 uint64
+	x155, x154 = bits.Mul64(x144, 0xffffffff00000001)
+	var x156 uint64
+	var x157 uint64
+	x157, x156 = bits.Mul64(x144, 0xffffffff)
+	var x158 uint64
+	var x159 uint64
+	x159, x158 = bits.Mul64(x144, 0xffffffffffffffff)
+	var x160 uint64
+	var x161 uint64
+	x160, x161 = bits.Add64(x159, x156, uint64(0x0))
+	x162 := (uint64(p256Uint1(x161)) + x157)
+	var x164 uint64
+	_, x164 = bits.Add64(x144, x158, uint64(0x0))
+	var x165 uint64
+	var x166 uint64
+	x165, x166 = bits.Add64(x146, x160, uint64(p256Uint1(x164)))
+	var x167 uint64
+	var x168 uint64
+	x167, x168 = bits.Add64(x148, x162, uint64(p256Uint1(x166)))
+	var x169 uint64
+	var x170 uint64
+	x169, x170 = bits.Add64(x150, x154, uint64(p256Uint1(x168)))
+	var x171 uint64
+	var x172 uint64
+	x171, x172 = bits.Add64(x152, x155, uint64(p256Uint1(x170)))
+	x173 := (uint64(p256Uint1(x172)) + uint64(p256Uint1(x153)))
+	var x174 uint64
+	var x175 uint64
+	x174, x175 = bits.Sub64(x165, 0xffffffffffffffff, uint64(0x0))
+	var x176 uint64
+	var x177 uint64
+	x176, x177 = bits.Sub64(x167, 0xffffffff, uint64(p256Uint1(x175)))
+	var x178 uint64
+	var x179 uint64
+	x178, x179 = bits.Sub64(x169, uint64(0x0), uint64(p256Uint1(x177)))
+	var x180 uint64
+	var x181 uint64
+	x180, x181 = bits.Sub64(x171, 0xffffffff00000001, uint64(p256Uint1(x179)))
+	var x183 uint64
+	_, x183 = bits.Sub64(x173, uint64(0x0), uint64(p256Uint1(x181)))
+	var x184 uint64
+	p256CmovznzU64(&x184, p256Uint1(x183), x174, x165)
+	var x185 uint64
+	p256CmovznzU64(&x185, p256Uint1(x183), x176, x167)
+	var x186 uint64
+	p256CmovznzU64(&x186, p256Uint1(x183), x178, x169)
+	var x187 uint64
+	p256CmovznzU64(&x187, p256Uint1(x183), x180, x171)
+	out1[0] = x184
+	out1[1] = x185
+	out1[2] = x186
+	out1[3] = x187
+}
+
+// p256Square squares a field element in the Montgomery domain.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//
+// Postconditions:
+//
+//	eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) * eval (from_montgomery arg1)) mod m
+//	0 ≤ eval out1 < m
+func p256Square(out1 *p256MontgomeryDomainFieldElement, arg1 *p256MontgomeryDomainFieldElement) {
+	x1 := arg1[1]
+	x2 := arg1[2]
+	x3 := arg1[3]
+	x4 := arg1[0]
+	var x5 uint64
+	var x6 uint64
+	x6, x5 = bits.Mul64(x4, arg1[3])
+	var x7 uint64
+	var x8 uint64
+	x8, x7 = bits.Mul64(x4, arg1[2])
+	var x9 uint64
+	var x10 uint64
+	x10, x9 = bits.Mul64(x4, arg1[1])
+	var x11 uint64
+	var x12 uint64
+	x12, x11 = bits.Mul64(x4, arg1[0])
+	var x13 uint64
+	var x14 uint64
+	x13, x14 = bits.Add64(x12, x9, uint64(0x0))
+	var x15 uint64
+	var x16 uint64
+	x15, x16 = bits.Add64(x10, x7, uint64(p256Uint1(x14)))
+	var x17 uint64
+	var x18 uint64
+	x17, x18 = bits.Add64(x8, x5, uint64(p256Uint1(x16)))
+	x19 := (uint64(p256Uint1(x18)) + x6)
+	var x20 uint64
+	var x21 uint64
+	x21, x20 = bits.Mul64(x11, 0xffffffff00000001)
+	var x22 uint64
+	var x23 uint64
+	x23, x22 = bits.Mul64(x11, 0xffffffff)
+	var x24 uint64
+	var x25 uint64
+	x25, x24 = bits.Mul64(x11, 0xffffffffffffffff)
+	var x26 uint64
+	var x27 uint64
+	x26, x27 = bits.Add64(x25, x22, uint64(0x0))
+	x28 := (uint64(p256Uint1(x27)) + x23)
+	var x30 uint64
+	_, x30 = bits.Add64(x11, x24, uint64(0x0))
+	var x31 uint64
+	var x32 uint64
+	x31, x32 = bits.Add64(x13, x26, uint64(p256Uint1(x30)))
+	var x33 uint64
+	var x34 uint64
+	x33, x34 = bits.Add64(x15, x28, uint64(p256Uint1(x32)))
+	var x35 uint64
+	var x36 uint64
+	x35, x36 = bits.Add64(x17, x20, uint64(p256Uint1(x34)))
+	var x37 uint64
+	var x38 uint64
+	x37, x38 = bits.Add64(x19, x21, uint64(p256Uint1(x36)))
+	var x39 uint64
+	var x40 uint64
+	x40, x39 = bits.Mul64(x1, arg1[3])
+	var x41 uint64
+	var x42 uint64
+	x42, x41 = bits.Mul64(x1, arg1[2])
+	var x43 uint64
+	var x44 uint64
+	x44, x43 = bits.Mul64(x1, arg1[1])
+	var x45 uint64
+	var x46 uint64
+	x46, x45 = bits.Mul64(x1, arg1[0])
+	var x47 uint64
+	var x48 uint64
+	x47, x48 = bits.Add64(x46, x43, uint64(0x0))
+	var x49 uint64
+	var x50 uint64
+	x49, x50 = bits.Add64(x44, x41, uint64(p256Uint1(x48)))
+	var x51 uint64
+	var x52 uint64
+	x51, x52 = bits.Add64(x42, x39, uint64(p256Uint1(x50)))
+	x53 := (uint64(p256Uint1(x52)) + x40)
+	var x54 uint64
+	var x55 uint64
+	x54, x55 = bits.Add64(x31, x45, uint64(0x0))
+	var x56 uint64
+	var x57 uint64
+	x56, x57 = bits.Add64(x33, x47, uint64(p256Uint1(x55)))
+	var x58 uint64
+	var x59 uint64
+	x58, x59 = bits.Add64(x35, x49, uint64(p256Uint1(x57)))
+	var x60 uint64
+	var x61 uint64
+	x60, x61 = bits.Add64(x37, x51, uint64(p256Uint1(x59)))
+	var x62 uint64
+	var x63 uint64
+	x62, x63 = bits.Add64(uint64(p256Uint1(x38)), x53, uint64(p256Uint1(x61)))
+	var x64 uint64
+	var x65 uint64
+	x65, x64 = bits.Mul64(x54, 0xffffffff00000001)
+	var x66 uint64
+	var x67 uint64
+	x67, x66 = bits.Mul64(x54, 0xffffffff)
+	var x68 uint64
+	var x69 uint64
+	x69, x68 = bits.Mul64(x54, 0xffffffffffffffff)
+	var x70 uint64
+	var x71 uint64
+	x70, x71 = bits.Add64(x69, x66, uint64(0x0))
+	x72 := (uint64(p256Uint1(x71)) + x67)
+	var x74 uint64
+	_, x74 = bits.Add64(x54, x68, uint64(0x0))
+	var x75 uint64
+	var x76 uint64
+	x75, x76 = bits.Add64(x56, x70, uint64(p256Uint1(x74)))
+	var x77 uint64
+	var x78 uint64
+	x77, x78 = bits.Add64(x58, x72, uint64(p256Uint1(x76)))
+	var x79 uint64
+	var x80 uint64
+	x79, x80 = bits.Add64(x60, x64, uint64(p256Uint1(x78)))
+	var x81 uint64
+	var x82 uint64
+	x81, x82 = bits.Add64(x62, x65, uint64(p256Uint1(x80)))
+	x83 := (uint64(p256Uint1(x82)) + uint64(p256Uint1(x63)))
+	var x84 uint64
+	var x85 uint64
+	x85, x84 = bits.Mul64(x2, arg1[3])
+	var x86 uint64
+	var x87 uint64
+	x87, x86 = bits.Mul64(x2, arg1[2])
+	var x88 uint64
+	var x89 uint64
+	x89, x88 = bits.Mul64(x2, arg1[1])
+	var x90 uint64
+	var x91 uint64
+	x91, x90 = bits.Mul64(x2, arg1[0])
+	var x92 uint64
+	var x93 uint64
+	x92, x93 = bits.Add64(x91, x88, uint64(0x0))
+	var x94 uint64
+	var x95 uint64
+	x94, x95 = bits.Add64(x89, x86, uint64(p256Uint1(x93)))
+	var x96 uint64
+	var x97 uint64
+	x96, x97 = bits.Add64(x87, x84, uint64(p256Uint1(x95)))
+	x98 := (uint64(p256Uint1(x97)) + x85)
+	var x99 uint64
+	var x100 uint64
+	x99, x100 = bits.Add64(x75, x90, uint64(0x0))
+	var x101 uint64
+	var x102 uint64
+	x101, x102 = bits.Add64(x77, x92, uint64(p256Uint1(x100)))
+	var x103 uint64
+	var x104 uint64
+	x103, x104 = bits.Add64(x79, x94, uint64(p256Uint1(x102)))
+	var x105 uint64
+	var x106 uint64
+	x105, x106 = bits.Add64(x81, x96, uint64(p256Uint1(x104)))
+	var x107 uint64
+	var x108 uint64
+	x107, x108 = bits.Add64(x83, x98, uint64(p256Uint1(x106)))
+	var x109 uint64
+	var x110 uint64
+	x110, x109 = bits.Mul64(x99, 0xffffffff00000001)
+	var x111 uint64
+	var x112 uint64
+	x112, x111 = bits.Mul64(x99, 0xffffffff)
+	var x113 uint64
+	var x114 uint64
+	x114, x113 = bits.Mul64(x99, 0xffffffffffffffff)
+	var x115 uint64
+	var x116 uint64
+	x115, x116 = bits.Add64(x114, x111, uint64(0x0))
+	x117 := (uint64(p256Uint1(x116)) + x112)
+	var x119 uint64
+	_, x119 = bits.Add64(x99, x113, uint64(0x0))
+	var x120 uint64
+	var x121 uint64
+	x120, x121 = bits.Add64(x101, x115, uint64(p256Uint1(x119)))
+	var x122 uint64
+	var x123 uint64
+	x122, x123 = bits.Add64(x103, x117, uint64(p256Uint1(x121)))
+	var x124 uint64
+	var x125 uint64
+	x124, x125 = bits.Add64(x105, x109, uint64(p256Uint1(x123)))
+	var x126 uint64
+	var x127 uint64
+	x126, x127 = bits.Add64(x107, x110, uint64(p256Uint1(x125)))
+	x128 := (uint64(p256Uint1(x127)) + uint64(p256Uint1(x108)))
+	var x129 uint64
+	var x130 uint64
+	x130, x129 = bits.Mul64(x3, arg1[3])
+	var x131 uint64
+	var x132 uint64
+	x132, x131 = bits.Mul64(x3, arg1[2])
+	var x133 uint64
+	var x134 uint64
+	x134, x133 = bits.Mul64(x3, arg1[1])
+	var x135 uint64
+	var x136 uint64
+	x136, x135 = bits.Mul64(x3, arg1[0])
+	var x137 uint64
+	var x138 uint64
+	x137, x138 = bits.Add64(x136, x133, uint64(0x0))
+	var x139 uint64
+	var x140 uint64
+	x139, x140 = bits.Add64(x134, x131, uint64(p256Uint1(x138)))
+	var x141 uint64
+	var x142 uint64
+	x141, x142 = bits.Add64(x132, x129, uint64(p256Uint1(x140)))
+	x143 := (uint64(p256Uint1(x142)) + x130)
+	var x144 uint64
+	var x145 uint64
+	x144, x145 = bits.Add64(x120, x135, uint64(0x0))
+	var x146 uint64
+	var x147 uint64
+	x146, x147 = bits.Add64(x122, x137, uint64(p256Uint1(x145)))
+	var x148 uint64
+	var x149 uint64
+	x148, x149 = bits.Add64(x124, x139, uint64(p256Uint1(x147)))
+	var x150 uint64
+	var x151 uint64
+	x150, x151 = bits.Add64(x126, x141, uint64(p256Uint1(x149)))
+	var x152 uint64
+	var x153 uint64
+	x152, x153 = bits.Add64(x128, x143, uint64(p256Uint1(x151)))
+	var x154 uint64
+	var x155 uint64
+	x155, x154 = bits.Mul64(x144, 0xffffffff00000001)
+	var x156 uint64
+	var x157 uint64
+	x157, x156 = bits.Mul64(x144, 0xffffffff)
+	var x158 uint64
+	var x159 uint64
+	x159, x158 = bits.Mul64(x144, 0xffffffffffffffff)
+	var x160 uint64
+	var x161 uint64
+	x160, x161 = bits.Add64(x159, x156, uint64(0x0))
+	x162 := (uint64(p256Uint1(x161)) + x157)
+	var x164 uint64
+	_, x164 = bits.Add64(x144, x158, uint64(0x0))
+	var x165 uint64
+	var x166 uint64
+	x165, x166 = bits.Add64(x146, x160, uint64(p256Uint1(x164)))
+	var x167 uint64
+	var x168 uint64
+	x167, x168 = bits.Add64(x148, x162, uint64(p256Uint1(x166)))
+	var x169 uint64
+	var x170 uint64
+	x169, x170 = bits.Add64(x150, x154, uint64(p256Uint1(x168)))
+	var x171 uint64
+	var x172 uint64
+	x171, x172 = bits.Add64(x152, x155, uint64(p256Uint1(x170)))
+	x173 := (uint64(p256Uint1(x172)) + uint64(p256Uint1(x153)))
+	var x174 uint64
+	var x175 uint64
+	x174, x175 = bits.Sub64(x165, 0xffffffffffffffff, uint64(0x0))
+	var x176 uint64
+	var x177 uint64
+	x176, x177 = bits.Sub64(x167, 0xffffffff, uint64(p256Uint1(x175)))
+	var x178 uint64
+	var x179 uint64
+	x178, x179 = bits.Sub64(x169, uint64(0x0), uint64(p256Uint1(x177)))
+	var x180 uint64
+	var x181 uint64
+	x180, x181 = bits.Sub64(x171, 0xffffffff00000001, uint64(p256Uint1(x179)))
+	var x183 uint64
+	_, x183 = bits.Sub64(x173, uint64(0x0), uint64(p256Uint1(x181)))
+	var x184 uint64
+	p256CmovznzU64(&x184, p256Uint1(x183), x174, x165)
+	var x185 uint64
+	p256CmovznzU64(&x185, p256Uint1(x183), x176, x167)
+	var x186 uint64
+	p256CmovznzU64(&x186, p256Uint1(x183), x178, x169)
+	var x187 uint64
+	p256CmovznzU64(&x187, p256Uint1(x183), x180, x171)
+	out1[0] = x184
+	out1[1] = x185
+	out1[2] = x186
+	out1[3] = x187
+}
+
+// p256Add adds two field elements in the Montgomery domain.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//	0 ≤ eval arg2 < m
+//
+// Postconditions:
+//
+//	eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) + eval (from_montgomery arg2)) mod m
+//	0 ≤ eval out1 < m
+func p256Add(out1 *p256MontgomeryDomainFieldElement, arg1 *p256MontgomeryDomainFieldElement, arg2 *p256MontgomeryDomainFieldElement) {
+	var x1 uint64
+	var x2 uint64
+	x1, x2 = bits.Add64(arg1[0], arg2[0], uint64(0x0))
+	var x3 uint64
+	var x4 uint64
+	x3, x4 = bits.Add64(arg1[1], arg2[1], uint64(p256Uint1(x2)))
+	var x5 uint64
+	var x6 uint64
+	x5, x6 = bits.Add64(arg1[2], arg2[2], uint64(p256Uint1(x4)))
+	var x7 uint64
+	var x8 uint64
+	x7, x8 = bits.Add64(arg1[3], arg2[3], uint64(p256Uint1(x6)))
+	var x9 uint64
+	var x10 uint64
+	x9, x10 = bits.Sub64(x1, 0xffffffffffffffff, uint64(0x0))
+	var x11 uint64
+	var x12 uint64
+	x11, x12 = bits.Sub64(x3, 0xffffffff, uint64(p256Uint1(x10)))
+	var x13 uint64
+	var x14 uint64
+	x13, x14 = bits.Sub64(x5, uint64(0x0), uint64(p256Uint1(x12)))
+	var x15 uint64
+	var x16 uint64
+	x15, x16 = bits.Sub64(x7, 0xffffffff00000001, uint64(p256Uint1(x14)))
+	var x18 uint64
+	_, x18 = bits.Sub64(uint64(p256Uint1(x8)), uint64(0x0), uint64(p256Uint1(x16)))
+	var x19 uint64
+	p256CmovznzU64(&x19, p256Uint1(x18), x9, x1)
+	var x20 uint64
+	p256CmovznzU64(&x20, p256Uint1(x18), x11, x3)
+	var x21 uint64
+	p256CmovznzU64(&x21, p256Uint1(x18), x13, x5)
+	var x22 uint64
+	p256CmovznzU64(&x22, p256Uint1(x18), x15, x7)
+	out1[0] = x19
+	out1[1] = x20
+	out1[2] = x21
+	out1[3] = x22
+}
+
+// p256Sub subtracts two field elements in the Montgomery domain.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//	0 ≤ eval arg2 < m
+//
+// Postconditions:
+//
+//	eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) - eval (from_montgomery arg2)) mod m
+//	0 ≤ eval out1 < m
+func p256Sub(out1 *p256MontgomeryDomainFieldElement, arg1 *p256MontgomeryDomainFieldElement, arg2 *p256MontgomeryDomainFieldElement) {
+	var x1 uint64
+	var x2 uint64
+	x1, x2 = bits.Sub64(arg1[0], arg2[0], uint64(0x0))
+	var x3 uint64
+	var x4 uint64
+	x3, x4 = bits.Sub64(arg1[1], arg2[1], uint64(p256Uint1(x2)))
+	var x5 uint64
+	var x6 uint64
+	x5, x6 = bits.Sub64(arg1[2], arg2[2], uint64(p256Uint1(x4)))
+	var x7 uint64
+	var x8 uint64
+	x7, x8 = bits.Sub64(arg1[3], arg2[3], uint64(p256Uint1(x6)))
+	var x9 uint64
+	p256CmovznzU64(&x9, p256Uint1(x8), uint64(0x0), 0xffffffffffffffff)
+	var x10 uint64
+	var x11 uint64
+	x10, x11 = bits.Add64(x1, x9, uint64(0x0))
+	var x12 uint64
+	var x13 uint64
+	x12, x13 = bits.Add64(x3, (x9 & 0xffffffff), uint64(p256Uint1(x11)))
+	var x14 uint64
+	var x15 uint64
+	x14, x15 = bits.Add64(x5, uint64(0x0), uint64(p256Uint1(x13)))
+	var x16 uint64
+	x16, _ = bits.Add64(x7, (x9 & 0xffffffff00000001), uint64(p256Uint1(x15)))
+	out1[0] = x10
+	out1[1] = x12
+	out1[2] = x14
+	out1[3] = x16
+}
+
+// p256SetOne returns the field element one in the Montgomery domain.
+//
+// Postconditions:
+//
+//	eval (from_montgomery out1) mod m = 1 mod m
+//	0 ≤ eval out1 < m
+func p256SetOne(out1 *p256MontgomeryDomainFieldElement) {
+	out1[0] = uint64(0x1)
+	out1[1] = 0xffffffff00000000
+	out1[2] = 0xffffffffffffffff
+	out1[3] = 0xfffffffe
+}
+
+// p256FromMontgomery translates a field element out of the Montgomery domain.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//
+// Postconditions:
+//
+//	eval out1 mod m = (eval arg1 * ((2^64)⁻¹ mod m)^4) mod m
+//	0 ≤ eval out1 < m
+func p256FromMontgomery(out1 *p256NonMontgomeryDomainFieldElement, arg1 *p256MontgomeryDomainFieldElement) {
+	x1 := arg1[0]
+	var x2 uint64
+	var x3 uint64
+	x3, x2 = bits.Mul64(x1, 0xffffffff00000001)
+	var x4 uint64
+	var x5 uint64
+	x5, x4 = bits.Mul64(x1, 0xffffffff)
+	var x6 uint64
+	var x7 uint64
+	x7, x6 = bits.Mul64(x1, 0xffffffffffffffff)
+	var x8 uint64
+	var x9 uint64
+	x8, x9 = bits.Add64(x7, x4, uint64(0x0))
+	var x11 uint64
+	_, x11 = bits.Add64(x1, x6, uint64(0x0))
+	var x12 uint64
+	var x13 uint64
+	x12, x13 = bits.Add64(uint64(0x0), x8, uint64(p256Uint1(x11)))
+	var x14 uint64
+	var x15 uint64
+	x14, x15 = bits.Add64(x12, arg1[1], uint64(0x0))
+	var x16 uint64
+	var x17 uint64
+	x17, x16 = bits.Mul64(x14, 0xffffffff00000001)
+	var x18 uint64
+	var x19 uint64
+	x19, x18 = bits.Mul64(x14, 0xffffffff)
+	var x20 uint64
+	var x21 uint64
+	x21, x20 = bits.Mul64(x14, 0xffffffffffffffff)
+	var x22 uint64
+	var x23 uint64
+	x22, x23 = bits.Add64(x21, x18, uint64(0x0))
+	var x25 uint64
+	_, x25 = bits.Add64(x14, x20, uint64(0x0))
+	var x26 uint64
+	var x27 uint64
+	x26, x27 = bits.Add64((uint64(p256Uint1(x15)) + (uint64(p256Uint1(x13)) + (uint64(p256Uint1(x9)) + x5))), x22, uint64(p256Uint1(x25)))
+	var x28 uint64
+	var x29 uint64
+	x28, x29 = bits.Add64(x2, (uint64(p256Uint1(x23)) + x19), uint64(p256Uint1(x27)))
+	var x30 uint64
+	var x31 uint64
+	x30, x31 = bits.Add64(x3, x16, uint64(p256Uint1(x29)))
+	var x32 uint64
+	var x33 uint64
+	x32, x33 = bits.Add64(x26, arg1[2], uint64(0x0))
+	var x34 uint64
+	var x35 uint64
+	x34, x35 = bits.Add64(x28, uint64(0x0), uint64(p256Uint1(x33)))
+	var x36 uint64
+	var x37 uint64
+	x36, x37 = bits.Add64(x30, uint64(0x0), uint64(p256Uint1(x35)))
+	var x38 uint64
+	var x39 uint64
+	x39, x38 = bits.Mul64(x32, 0xffffffff00000001)
+	var x40 uint64
+	var x41 uint64
+	x41, x40 = bits.Mul64(x32, 0xffffffff)
+	var x42 uint64
+	var x43 uint64
+	x43, x42 = bits.Mul64(x32, 0xffffffffffffffff)
+	var x44 uint64
+	var x45 uint64
+	x44, x45 = bits.Add64(x43, x40, uint64(0x0))
+	var x47 uint64
+	_, x47 = bits.Add64(x32, x42, uint64(0x0))
+	var x48 uint64
+	var x49 uint64
+	x48, x49 = bits.Add64(x34, x44, uint64(p256Uint1(x47)))
+	var x50 uint64
+	var x51 uint64
+	x50, x51 = bits.Add64(x36, (uint64(p256Uint1(x45)) + x41), uint64(p256Uint1(x49)))
+	var x52 uint64
+	var x53 uint64
+	x52, x53 = bits.Add64((uint64(p256Uint1(x37)) + (uint64(p256Uint1(x31)) + x17)), x38, uint64(p256Uint1(x51)))
+	var x54 uint64
+	var x55 uint64
+	x54, x55 = bits.Add64(x48, arg1[3], uint64(0x0))
+	var x56 uint64
+	var x57 uint64
+	x56, x57 = bits.Add64(x50, uint64(0x0), uint64(p256Uint1(x55)))
+	var x58 uint64
+	var x59 uint64
+	x58, x59 = bits.Add64(x52, uint64(0x0), uint64(p256Uint1(x57)))
+	var x60 uint64
+	var x61 uint64
+	x61, x60 = bits.Mul64(x54, 0xffffffff00000001)
+	var x62 uint64
+	var x63 uint64
+	x63, x62 = bits.Mul64(x54, 0xffffffff)
+	var x64 uint64
+	var x65 uint64
+	x65, x64 = bits.Mul64(x54, 0xffffffffffffffff)
+	var x66 uint64
+	var x67 uint64
+	x66, x67 = bits.Add64(x65, x62, uint64(0x0))
+	var x69 uint64
+	_, x69 = bits.Add64(x54, x64, uint64(0x0))
+	var x70 uint64
+	var x71 uint64
+	x70, x71 = bits.Add64(x56, x66, uint64(p256Uint1(x69)))
+	var x72 uint64
+	var x73 uint64
+	x72, x73 = bits.Add64(x58, (uint64(p256Uint1(x67)) + x63), uint64(p256Uint1(x71)))
+	var x74 uint64
+	var x75 uint64
+	x74, x75 = bits.Add64((uint64(p256Uint1(x59)) + (uint64(p256Uint1(x53)) + x39)), x60, uint64(p256Uint1(x73)))
+	x76 := (uint64(p256Uint1(x75)) + x61)
+	var x77 uint64
+	var x78 uint64
+	x77, x78 = bits.Sub64(x70, 0xffffffffffffffff, uint64(0x0))
+	var x79 uint64
+	var x80 uint64
+	x79, x80 = bits.Sub64(x72, 0xffffffff, uint64(p256Uint1(x78)))
+	var x81 uint64
+	var x82 uint64
+	x81, x82 = bits.Sub64(x74, uint64(0x0), uint64(p256Uint1(x80)))
+	var x83 uint64
+	var x84 uint64
+	x83, x84 = bits.Sub64(x76, 0xffffffff00000001, uint64(p256Uint1(x82)))
+	var x86 uint64
+	_, x86 = bits.Sub64(uint64(0x0), uint64(0x0), uint64(p256Uint1(x84)))
+	var x87 uint64
+	p256CmovznzU64(&x87, p256Uint1(x86), x77, x70)
+	var x88 uint64
+	p256CmovznzU64(&x88, p256Uint1(x86), x79, x72)
+	var x89 uint64
+	p256CmovznzU64(&x89, p256Uint1(x86), x81, x74)
+	var x90 uint64
+	p256CmovznzU64(&x90, p256Uint1(x86), x83, x76)
+	out1[0] = x87
+	out1[1] = x88
+	out1[2] = x89
+	out1[3] = x90
+}
+
+// p256ToMontgomery translates a field element into the Montgomery domain.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//
+// Postconditions:
+//
+//	eval (from_montgomery out1) mod m = eval arg1 mod m
+//	0 ≤ eval out1 < m
+func p256ToMontgomery(out1 *p256MontgomeryDomainFieldElement, arg1 *p256NonMontgomeryDomainFieldElement) {
+	x1 := arg1[1]
+	x2 := arg1[2]
+	x3 := arg1[3]
+	x4 := arg1[0]
+	var x5 uint64
+	var x6 uint64
+	x6, x5 = bits.Mul64(x4, 0x4fffffffd)
+	var x7 uint64
+	var x8 uint64
+	x8, x7 = bits.Mul64(x4, 0xfffffffffffffffe)
+	var x9 uint64
+	var x10 uint64
+	x10, x9 = bits.Mul64(x4, 0xfffffffbffffffff)
+	var x11 uint64
+	var x12 uint64
+	x12, x11 = bits.Mul64(x4, 0x3)
+	var x13 uint64
+	var x14 uint64
+	x13, x14 = bits.Add64(x12, x9, uint64(0x0))
+	var x15 uint64
+	var x16 uint64
+	x15, x16 = bits.Add64(x10, x7, uint64(p256Uint1(x14)))
+	var x17 uint64
+	var x18 uint64
+	x17, x18 = bits.Add64(x8, x5, uint64(p256Uint1(x16)))
+	var x19 uint64
+	var x20 uint64
+	x20, x19 = bits.Mul64(x11, 0xffffffff00000001)
+	var x21 uint64
+	var x22 uint64
+	x22, x21 = bits.Mul64(x11, 0xffffffff)
+	var x23 uint64
+	var x24 uint64
+	x24, x23 = bits.Mul64(x11, 0xffffffffffffffff)
+	var x25 uint64
+	var x26 uint64
+	x25, x26 = bits.Add64(x24, x21, uint64(0x0))
+	var x28 uint64
+	_, x28 = bits.Add64(x11, x23, uint64(0x0))
+	var x29 uint64
+	var x30 uint64
+	x29, x30 = bits.Add64(x13, x25, uint64(p256Uint1(x28)))
+	var x31 uint64
+	var x32 uint64
+	x31, x32 = bits.Add64(x15, (uint64(p256Uint1(x26)) + x22), uint64(p256Uint1(x30)))
+	var x33 uint64
+	var x34 uint64
+	x33, x34 = bits.Add64(x17, x19, uint64(p256Uint1(x32)))
+	var x35 uint64
+	var x36 uint64
+	x35, x36 = bits.Add64((uint64(p256Uint1(x18)) + x6), x20, uint64(p256Uint1(x34)))
+	var x37 uint64
+	var x38 uint64
+	x38, x37 = bits.Mul64(x1, 0x4fffffffd)
+	var x39 uint64
+	var x40 uint64
+	x40, x39 = bits.Mul64(x1, 0xfffffffffffffffe)
+	var x41 uint64
+	var x42 uint64
+	x42, x41 = bits.Mul64(x1, 0xfffffffbffffffff)
+	var x43 uint64
+	var x44 uint64
+	x44, x43 = bits.Mul64(x1, 0x3)
+	var x45 uint64
+	var x46 uint64
+	x45, x46 = bits.Add64(x44, x41, uint64(0x0))
+	var x47 uint64
+	var x48 uint64
+	x47, x48 = bits.Add64(x42, x39, uint64(p256Uint1(x46)))
+	var x49 uint64
+	var x50 uint64
+	x49, x50 = bits.Add64(x40, x37, uint64(p256Uint1(x48)))
+	var x51 uint64
+	var x52 uint64
+	x51, x52 = bits.Add64(x29, x43, uint64(0x0))
+	var x53 uint64
+	var x54 uint64
+	x53, x54 = bits.Add64(x31, x45, uint64(p256Uint1(x52)))
+	var x55 uint64
+	var x56 uint64
+	x55, x56 = bits.Add64(x33, x47, uint64(p256Uint1(x54)))
+	var x57 uint64
+	var x58 uint64
+	x57, x58 = bits.Add64(x35, x49, uint64(p256Uint1(x56)))
+	var x59 uint64
+	var x60 uint64
+	x60, x59 = bits.Mul64(x51, 0xffffffff00000001)
+	var x61 uint64
+	var x62 uint64
+	x62, x61 = bits.Mul64(x51, 0xffffffff)
+	var x63 uint64
+	var x64 uint64
+	x64, x63 = bits.Mul64(x51, 0xffffffffffffffff)
+	var x65 uint64
+	var x66 uint64
+	x65, x66 = bits.Add64(x64, x61, uint64(0x0))
+	var x68 uint64
+	_, x68 = bits.Add64(x51, x63, uint64(0x0))
+	var x69 uint64
+	var x70 uint64
+	x69, x70 = bits.Add64(x53, x65, uint64(p256Uint1(x68)))
+	var x71 uint64
+	var x72 uint64
+	x71, x72 = bits.Add64(x55, (uint64(p256Uint1(x66)) + x62), uint64(p256Uint1(x70)))
+	var x73 uint64
+	var x74 uint64
+	x73, x74 = bits.Add64(x57, x59, uint64(p256Uint1(x72)))
+	var x75 uint64
+	var x76 uint64
+	x75, x76 = bits.Add64(((uint64(p256Uint1(x58)) + uint64(p256Uint1(x36))) + (uint64(p256Uint1(x50)) + x38)), x60, uint64(p256Uint1(x74)))
+	var x77 uint64
+	var x78 uint64
+	x78, x77 = bits.Mul64(x2, 0x4fffffffd)
+	var x79 uint64
+	var x80 uint64
+	x80, x79 = bits.Mul64(x2, 0xfffffffffffffffe)
+	var x81 uint64
+	var x82 uint64
+	x82, x81 = bits.Mul64(x2, 0xfffffffbffffffff)
+	var x83 uint64
+	var x84 uint64
+	x84, x83 = bits.Mul64(x2, 0x3)
+	var x85 uint64
+	var x86 uint64
+	x85, x86 = bits.Add64(x84, x81, uint64(0x0))
+	var x87 uint64
+	var x88 uint64
+	x87, x88 = bits.Add64(x82, x79, uint64(p256Uint1(x86)))
+	var x89 uint64
+	var x90 uint64
+	x89, x90 = bits.Add64(x80, x77, uint64(p256Uint1(x88)))
+	var x91 uint64
+	var x92 uint64
+	x91, x92 = bits.Add64(x69, x83, uint64(0x0))
+	var x93 uint64
+	var x94 uint64
+	x93, x94 = bits.Add64(x71, x85, uint64(p256Uint1(x92)))
+	var x95 uint64
+	var x96 uint64
+	x95, x96 = bits.Add64(x73, x87, uint64(p256Uint1(x94)))
+	var x97 uint64
+	var x98 uint64
+	x97, x98 = bits.Add64(x75, x89, uint64(p256Uint1(x96)))
+	var x99 uint64
+	var x100 uint64
+	x100, x99 = bits.Mul64(x91, 0xffffffff00000001)
+	var x101 uint64
+	var x102 uint64
+	x102, x101 = bits.Mul64(x91, 0xffffffff)
+	var x103 uint64
+	var x104 uint64
+	x104, x103 = bits.Mul64(x91, 0xffffffffffffffff)
+	var x105 uint64
+	var x106 uint64
+	x105, x106 = bits.Add64(x104, x101, uint64(0x0))
+	var x108 uint64
+	_, x108 = bits.Add64(x91, x103, uint64(0x0))
+	var x109 uint64
+	var x110 uint64
+	x109, x110 = bits.Add64(x93, x105, uint64(p256Uint1(x108)))
+	var x111 uint64
+	var x112 uint64
+	x111, x112 = bits.Add64(x95, (uint64(p256Uint1(x106)) + x102), uint64(p256Uint1(x110)))
+	var x113 uint64
+	var x114 uint64
+	x113, x114 = bits.Add64(x97, x99, uint64(p256Uint1(x112)))
+	var x115 uint64
+	var x116 uint64
+	x115, x116 = bits.Add64(((uint64(p256Uint1(x98)) + uint64(p256Uint1(x76))) + (uint64(p256Uint1(x90)) + x78)), x100, uint64(p256Uint1(x114)))
+	var x117 uint64
+	var x118 uint64
+	x118, x117 = bits.Mul64(x3, 0x4fffffffd)
+	var x119 uint64
+	var x120 uint64
+	x120, x119 = bits.Mul64(x3, 0xfffffffffffffffe)
+	var x121 uint64
+	var x122 uint64
+	x122, x121 = bits.Mul64(x3, 0xfffffffbffffffff)
+	var x123 uint64
+	var x124 uint64
+	x124, x123 = bits.Mul64(x3, 0x3)
+	var x125 uint64
+	var x126 uint64
+	x125, x126 = bits.Add64(x124, x121, uint64(0x0))
+	var x127 uint64
+	var x128 uint64
+	x127, x128 = bits.Add64(x122, x119, uint64(p256Uint1(x126)))
+	var x129 uint64
+	var x130 uint64
+	x129, x130 = bits.Add64(x120, x117, uint64(p256Uint1(x128)))
+	var x131 uint64
+	var x132 uint64
+	x131, x132 = bits.Add64(x109, x123, uint64(0x0))
+	var x133 uint64
+	var x134 uint64
+	x133, x134 = bits.Add64(x111, x125, uint64(p256Uint1(x132)))
+	var x135 uint64
+	var x136 uint64
+	x135, x136 = bits.Add64(x113, x127, uint64(p256Uint1(x134)))
+	var x137 uint64
+	var x138 uint64
+	x137, x138 = bits.Add64(x115, x129, uint64(p256Uint1(x136)))
+	var x139 uint64
+	var x140 uint64
+	x140, x139 = bits.Mul64(x131, 0xffffffff00000001)
+	var x141 uint64
+	var x142 uint64
+	x142, x141 = bits.Mul64(x131, 0xffffffff)
+	var x143 uint64
+	var x144 uint64
+	x144, x143 = bits.Mul64(x131, 0xffffffffffffffff)
+	var x145 uint64
+	var x146 uint64
+	x145, x146 = bits.Add64(x144, x141, uint64(0x0))
+	var x148 uint64
+	_, x148 = bits.Add64(x131, x143, uint64(0x0))
+	var x149 uint64
+	var x150 uint64
+	x149, x150 = bits.Add64(x133, x145, uint64(p256Uint1(x148)))
+	var x151 uint64
+	var x152 uint64
+	x151, x152 = bits.Add64(x135, (uint64(p256Uint1(x146)) + x142), uint64(p256Uint1(x150)))
+	var x153 uint64
+	var x154 uint64
+	x153, x154 = bits.Add64(x137, x139, uint64(p256Uint1(x152)))
+	var x155 uint64
+	var x156 uint64
+	x155, x156 = bits.Add64(((uint64(p256Uint1(x138)) + uint64(p256Uint1(x116))) + (uint64(p256Uint1(x130)) + x118)), x140, uint64(p256Uint1(x154)))
+	var x157 uint64
+	var x158 uint64
+	x157, x158 = bits.Sub64(x149, 0xffffffffffffffff, uint64(0x0))
+	var x159 uint64
+	var x160 uint64
+	x159, x160 = bits.Sub64(x151, 0xffffffff, uint64(p256Uint1(x158)))
+	var x161 uint64
+	var x162 uint64
+	x161, x162 = bits.Sub64(x153, uint64(0x0), uint64(p256Uint1(x160)))
+	var x163 uint64
+	var x164 uint64
+	x163, x164 = bits.Sub64(x155, 0xffffffff00000001, uint64(p256Uint1(x162)))
+	var x166 uint64
+	_, x166 = bits.Sub64(uint64(p256Uint1(x156)), uint64(0x0), uint64(p256Uint1(x164)))
+	var x167 uint64
+	p256CmovznzU64(&x167, p256Uint1(x166), x157, x149)
+	var x168 uint64
+	p256CmovznzU64(&x168, p256Uint1(x166), x159, x151)
+	var x169 uint64
+	p256CmovznzU64(&x169, p256Uint1(x166), x161, x153)
+	var x170 uint64
+	p256CmovznzU64(&x170, p256Uint1(x166), x163, x155)
+	out1[0] = x167
+	out1[1] = x168
+	out1[2] = x169
+	out1[3] = x170
+}
+
+// p256Selectznz is a multi-limb conditional select.
+//
+// Postconditions:
+//
+//	eval out1 = (if arg1 = 0 then eval arg2 else eval arg3)
+//
+// Input Bounds:
+//
+//	arg1: [0x0 ~> 0x1]
+//	arg2: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
+//	arg3: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
+//
+// Output Bounds:
+//
+//	out1: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
+func p256Selectznz(out1 *[4]uint64, arg1 p256Uint1, arg2 *[4]uint64, arg3 *[4]uint64) {
+	var x1 uint64
+	p256CmovznzU64(&x1, arg1, arg2[0], arg3[0])
+	var x2 uint64
+	p256CmovznzU64(&x2, arg1, arg2[1], arg3[1])
+	var x3 uint64
+	p256CmovznzU64(&x3, arg1, arg2[2], arg3[2])
+	var x4 uint64
+	p256CmovznzU64(&x4, arg1, arg2[3], arg3[3])
+	out1[0] = x1
+	out1[1] = x2
+	out1[2] = x3
+	out1[3] = x4
+}
+
+// p256ToBytes serializes a field element NOT in the Montgomery domain to bytes in little-endian order.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//
+// Postconditions:
+//
+//	out1 = map (λ x, ⌊((eval arg1 mod m) mod 2^(8 * (x + 1))) / 2^(8 * x)⌋) [0..31]
+//
+// Input Bounds:
+//
+//	arg1: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
+//
+// Output Bounds:
+//
+//	out1: [[0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff]]
+func p256ToBytes(out1 *[32]uint8, arg1 *[4]uint64) {
+	x1 := arg1[3]
+	x2 := arg1[2]
+	x3 := arg1[1]
+	x4 := arg1[0]
+	x5 := (uint8(x4) & 0xff)
+	x6 := (x4 >> 8)
+	x7 := (uint8(x6) & 0xff)
+	x8 := (x6 >> 8)
+	x9 := (uint8(x8) & 0xff)
+	x10 := (x8 >> 8)
+	x11 := (uint8(x10) & 0xff)
+	x12 := (x10 >> 8)
+	x13 := (uint8(x12) & 0xff)
+	x14 := (x12 >> 8)
+	x15 := (uint8(x14) & 0xff)
+	x16 := (x14 >> 8)
+	x17 := (uint8(x16) & 0xff)
+	x18 := uint8((x16 >> 8))
+	x19 := (uint8(x3) & 0xff)
+	x20 := (x3 >> 8)
+	x21 := (uint8(x20) & 0xff)
+	x22 := (x20 >> 8)
+	x23 := (uint8(x22) & 0xff)
+	x24 := (x22 >> 8)
+	x25 := (uint8(x24) & 0xff)
+	x26 := (x24 >> 8)
+	x27 := (uint8(x26) & 0xff)
+	x28 := (x26 >> 8)
+	x29 := (uint8(x28) & 0xff)
+	x30 := (x28 >> 8)
+	x31 := (uint8(x30) & 0xff)
+	x32 := uint8((x30 >> 8))
+	x33 := (uint8(x2) & 0xff)
+	x34 := (x2 >> 8)
+	x35 := (uint8(x34) & 0xff)
+	x36 := (x34 >> 8)
+	x37 := (uint8(x36) & 0xff)
+	x38 := (x36 >> 8)
+	x39 := (uint8(x38) & 0xff)
+	x40 := (x38 >> 8)
+	x41 := (uint8(x40) & 0xff)
+	x42 := (x40 >> 8)
+	x43 := (uint8(x42) & 0xff)
+	x44 := (x42 >> 8)
+	x45 := (uint8(x44) & 0xff)
+	x46 := uint8((x44 >> 8))
+	x47 := (uint8(x1) & 0xff)
+	x48 := (x1 >> 8)
+	x49 := (uint8(x48) & 0xff)
+	x50 := (x48 >> 8)
+	x51 := (uint8(x50) & 0xff)
+	x52 := (x50 >> 8)
+	x53 := (uint8(x52) & 0xff)
+	x54 := (x52 >> 8)
+	x55 := (uint8(x54) & 0xff)
+	x56 := (x54 >> 8)
+	x57 := (uint8(x56) & 0xff)
+	x58 := (x56 >> 8)
+	x59 := (uint8(x58) & 0xff)
+	x60 := uint8((x58 >> 8))
+	out1[0] = x5
+	out1[1] = x7
+	out1[2] = x9
+	out1[3] = x11
+	out1[4] = x13
+	out1[5] = x15
+	out1[6] = x17
+	out1[7] = x18
+	out1[8] = x19
+	out1[9] = x21
+	out1[10] = x23
+	out1[11] = x25
+	out1[12] = x27
+	out1[13] = x29
+	out1[14] = x31
+	out1[15] = x32
+	out1[16] = x33
+	out1[17] = x35
+	out1[18] = x37
+	out1[19] = x39
+	out1[20] = x41
+	out1[21] = x43
+	out1[22] = x45
+	out1[23] = x46
+	out1[24] = x47
+	out1[25] = x49
+	out1[26] = x51
+	out1[27] = x53
+	out1[28] = x55
+	out1[29] = x57
+	out1[30] = x59
+	out1[31] = x60
+}
+
+// p256FromBytes deserializes a field element NOT in the Montgomery domain from bytes in little-endian order.
+//
+// Preconditions:
+//
+//	0 ≤ bytes_eval arg1 < m
+//
+// Postconditions:
+//
+//	eval out1 mod m = bytes_eval arg1 mod m
+//	0 ≤ eval out1 < m
+//
+// Input Bounds:
+//
+//	arg1: [[0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff]]
+//
+// Output Bounds:
+//
+//	out1: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
+func p256FromBytes(out1 *[4]uint64, arg1 *[32]uint8) {
+	x1 := (uint64(arg1[31]) << 56)
+	x2 := (uint64(arg1[30]) << 48)
+	x3 := (uint64(arg1[29]) << 40)
+	x4 := (uint64(arg1[28]) << 32)
+	x5 := (uint64(arg1[27]) << 24)
+	x6 := (uint64(arg1[26]) << 16)
+	x7 := (uint64(arg1[25]) << 8)
+	x8 := arg1[24]
+	x9 := (uint64(arg1[23]) << 56)
+	x10 := (uint64(arg1[22]) << 48)
+	x11 := (uint64(arg1[21]) << 40)
+	x12 := (uint64(arg1[20]) << 32)
+	x13 := (uint64(arg1[19]) << 24)
+	x14 := (uint64(arg1[18]) << 16)
+	x15 := (uint64(arg1[17]) << 8)
+	x16 := arg1[16]
+	x17 := (uint64(arg1[15]) << 56)
+	x18 := (uint64(arg1[14]) << 48)
+	x19 := (uint64(arg1[13]) << 40)
+	x20 := (uint64(arg1[12]) << 32)
+	x21 := (uint64(arg1[11]) << 24)
+	x22 := (uint64(arg1[10]) << 16)
+	x23 := (uint64(arg1[9]) << 8)
+	x24 := arg1[8]
+	x25 := (uint64(arg1[7]) << 56)
+	x26 := (uint64(arg1[6]) << 48)
+	x27 := (uint64(arg1[5]) << 40)
+	x28 := (uint64(arg1[4]) << 32)
+	x29 := (uint64(arg1[3]) << 24)
+	x30 := (uint64(arg1[2]) << 16)
+	x31 := (uint64(arg1[1]) << 8)
+	x32 := arg1[0]
+	x33 := (x31 + uint64(x32))
+	x34 := (x30 + x33)
+	x35 := (x29 + x34)
+	x36 := (x28 + x35)
+	x37 := (x27 + x36)
+	x38 := (x26 + x37)
+	x39 := (x25 + x38)
+	x40 := (x23 + uint64(x24))
+	x41 := (x22 + x40)
+	x42 := (x21 + x41)
+	x43 := (x20 + x42)
+	x44 := (x19 + x43)
+	x45 := (x18 + x44)
+	x46 := (x17 + x45)
+	x47 := (x15 + uint64(x16))
+	x48 := (x14 + x47)
+	x49 := (x13 + x48)
+	x50 := (x12 + x49)
+	x51 := (x11 + x50)
+	x52 := (x10 + x51)
+	x53 := (x9 + x52)
+	x54 := (x7 + uint64(x8))
+	x55 := (x6 + x54)
+	x56 := (x5 + x55)
+	x57 := (x4 + x56)
+	x58 := (x3 + x57)
+	x59 := (x2 + x58)
+	x60 := (x1 + x59)
+	out1[0] = x39
+	out1[1] = x46
+	out1[2] = x53
+	out1[3] = x60
+}
diff --git a/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p256_invert.go b/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p256_invert.go
new file mode 100644
index 0000000000..d0101e1d4f
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p256_invert.go
@@ -0,0 +1,84 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Code generated by addchain. DO NOT EDIT.
+
+package fiat
+
+// Invert sets e = 1/x, and returns e.
+//
+// If x == 0, Invert returns e = 0.
+func (e *P256Element) Invert(x *P256Element) *P256Element {
+	// Inversion is implemented as exponentiation with exponent p − 2.
+	// The sequence of 12 multiplications and 255 squarings is derived from the
+	// following addition chain generated with github.com/mmcloughlin/addchain v0.4.0.
+	//
+	//	_10     = 2*1
+	//	_11     = 1 + _10
+	//	_110    = 2*_11
+	//	_111    = 1 + _110
+	//	_111000 = _111 << 3
+	//	_111111 = _111 + _111000
+	//	x12     = _111111 << 6 + _111111
+	//	x15     = x12 << 3 + _111
+	//	x16     = 2*x15 + 1
+	//	x32     = x16 << 16 + x16
+	//	i53     = x32 << 15
+	//	x47     = x15 + i53
+	//	i263    = ((i53 << 17 + 1) << 143 + x47) << 47
+	//	return    (x47 + i263) << 2 + 1
+	//
+
+	var z = new(P256Element).Set(e)
+	var t0 = new(P256Element)
+	var t1 = new(P256Element)
+
+	z.Square(x)
+	z.Mul(x, z)
+	z.Square(z)
+	z.Mul(x, z)
+	t0.Square(z)
+	for s := 1; s < 3; s++ {
+		t0.Square(t0)
+	}
+	t0.Mul(z, t0)
+	t1.Square(t0)
+	for s := 1; s < 6; s++ {
+		t1.Square(t1)
+	}
+	t0.Mul(t0, t1)
+	for s := 0; s < 3; s++ {
+		t0.Square(t0)
+	}
+	z.Mul(z, t0)
+	t0.Square(z)
+	t0.Mul(x, t0)
+	t1.Square(t0)
+	for s := 1; s < 16; s++ {
+		t1.Square(t1)
+	}
+	t0.Mul(t0, t1)
+	for s := 0; s < 15; s++ {
+		t0.Square(t0)
+	}
+	z.Mul(z, t0)
+	for s := 0; s < 17; s++ {
+		t0.Square(t0)
+	}
+	t0.Mul(x, t0)
+	for s := 0; s < 143; s++ {
+		t0.Square(t0)
+	}
+	t0.Mul(z, t0)
+	for s := 0; s < 47; s++ {
+		t0.Square(t0)
+	}
+	z.Mul(z, t0)
+	for s := 0; s < 2; s++ {
+		z.Square(z)
+	}
+	z.Mul(x, z)
+
+	return e.Set(z)
+}
diff --git a/contrib/go/_std_1.18/src/crypto/elliptic/internal/fiat/p384.go b/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p384.go
index 5474d77d48..5474d77d48 100644
--- a/contrib/go/_std_1.18/src/crypto/elliptic/internal/fiat/p384.go
+++ b/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p384.go
diff --git a/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p384_fiat64.go b/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p384_fiat64.go
new file mode 100644
index 0000000000..979eadd2df
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p384_fiat64.go
@@ -0,0 +1,3036 @@
+// Code generated by Fiat Cryptography. DO NOT EDIT.
+//
+// Autogenerated: word_by_word_montgomery --lang Go --no-wide-int --cmovznz-by-mul --relax-primitive-carry-to-bitwidth 32,64 --internal-static --public-function-case camelCase --public-type-case camelCase --private-function-case camelCase --private-type-case camelCase --doc-text-before-function-name '' --doc-newline-before-package-declaration --doc-prepend-header 'Code generated by Fiat Cryptography. DO NOT EDIT.' --package-name fiat --no-prefix-fiat p384 64 '2^384 - 2^128 - 2^96 + 2^32 - 1' mul square add sub one from_montgomery to_montgomery selectznz to_bytes from_bytes
+//
+// curve description: p384
+//
+// machine_wordsize = 64 (from "64")
+//
+// requested operations: mul, square, add, sub, one, from_montgomery, to_montgomery, selectznz, to_bytes, from_bytes
+//
+// m = 0xfffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffeffffffff0000000000000000ffffffff (from "2^384 - 2^128 - 2^96 + 2^32 - 1")
+//
+//
+//
+// NOTE: In addition to the bounds specified above each function, all
+//
+//   functions synthesized for this Montgomery arithmetic require the
+//
+//   input to be strictly less than the prime modulus (m), and also
+//
+//   require the input to be in the unique saturated representation.
+//
+//   All functions also ensure that these two properties are true of
+//
+//   return values.
+//
+//
+//
+// Computed values:
+//
+//   eval z = z[0] + (z[1] << 64) + (z[2] << 128) + (z[3] << 192) + (z[4] << 256) + (z[5] << 0x140)
+//
+//   bytes_eval z = z[0] + (z[1] << 8) + (z[2] << 16) + (z[3] << 24) + (z[4] << 32) + (z[5] << 40) + (z[6] << 48) + (z[7] << 56) + (z[8] << 64) + (z[9] << 72) + (z[10] << 80) + (z[11] << 88) + (z[12] << 96) + (z[13] << 104) + (z[14] << 112) + (z[15] << 120) + (z[16] << 128) + (z[17] << 136) + (z[18] << 144) + (z[19] << 152) + (z[20] << 160) + (z[21] << 168) + (z[22] << 176) + (z[23] << 184) + (z[24] << 192) + (z[25] << 200) + (z[26] << 208) + (z[27] << 216) + (z[28] << 224) + (z[29] << 232) + (z[30] << 240) + (z[31] << 248) + (z[32] << 256) + (z[33] << 0x108) + (z[34] << 0x110) + (z[35] << 0x118) + (z[36] << 0x120) + (z[37] << 0x128) + (z[38] << 0x130) + (z[39] << 0x138) + (z[40] << 0x140) + (z[41] << 0x148) + (z[42] << 0x150) + (z[43] << 0x158) + (z[44] << 0x160) + (z[45] << 0x168) + (z[46] << 0x170) + (z[47] << 0x178)
+//
+//   twos_complement_eval z = let x1 := z[0] + (z[1] << 64) + (z[2] << 128) + (z[3] << 192) + (z[4] << 256) + (z[5] << 0x140) in
+//
+//                            if x1 & (2^384-1) < 2^383 then x1 & (2^384-1) else (x1 & (2^384-1)) - 2^384
+
+package fiat
+
+import "math/bits"
+
+type p384Uint1 uint64 // We use uint64 instead of a more narrow type for performance reasons; see https://github.com/mit-plv/fiat-crypto/pull/1006#issuecomment-892625927
+type p384Int1 int64   // We use uint64 instead of a more narrow type for performance reasons; see https://github.com/mit-plv/fiat-crypto/pull/1006#issuecomment-892625927
+
+// The type p384MontgomeryDomainFieldElement is a field element in the Montgomery domain.
+//
+// Bounds: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
+type p384MontgomeryDomainFieldElement [6]uint64
+
+// The type p384NonMontgomeryDomainFieldElement is a field element NOT in the Montgomery domain.
+//
+// Bounds: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
+type p384NonMontgomeryDomainFieldElement [6]uint64
+
+// p384CmovznzU64 is a single-word conditional move.
+//
+// Postconditions:
+//
+//	out1 = (if arg1 = 0 then arg2 else arg3)
+//
+// Input Bounds:
+//
+//	arg1: [0x0 ~> 0x1]
+//	arg2: [0x0 ~> 0xffffffffffffffff]
+//	arg3: [0x0 ~> 0xffffffffffffffff]
+//
+// Output Bounds:
+//
+//	out1: [0x0 ~> 0xffffffffffffffff]
+func p384CmovznzU64(out1 *uint64, arg1 p384Uint1, arg2 uint64, arg3 uint64) {
+	x1 := (uint64(arg1) * 0xffffffffffffffff)
+	x2 := ((x1 & arg3) | ((^x1) & arg2))
+	*out1 = x2
+}
+
+// p384Mul multiplies two field elements in the Montgomery domain.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//	0 ≤ eval arg2 < m
+//
+// Postconditions:
+//
+//	eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) * eval (from_montgomery arg2)) mod m
+//	0 ≤ eval out1 < m
+func p384Mul(out1 *p384MontgomeryDomainFieldElement, arg1 *p384MontgomeryDomainFieldElement, arg2 *p384MontgomeryDomainFieldElement) {
+	x1 := arg1[1]
+	x2 := arg1[2]
+	x3 := arg1[3]
+	x4 := arg1[4]
+	x5 := arg1[5]
+	x6 := arg1[0]
+	var x7 uint64
+	var x8 uint64
+	x8, x7 = bits.Mul64(x6, arg2[5])
+	var x9 uint64
+	var x10 uint64
+	x10, x9 = bits.Mul64(x6, arg2[4])
+	var x11 uint64
+	var x12 uint64
+	x12, x11 = bits.Mul64(x6, arg2[3])
+	var x13 uint64
+	var x14 uint64
+	x14, x13 = bits.Mul64(x6, arg2[2])
+	var x15 uint64
+	var x16 uint64
+	x16, x15 = bits.Mul64(x6, arg2[1])
+	var x17 uint64
+	var x18 uint64
+	x18, x17 = bits.Mul64(x6, arg2[0])
+	var x19 uint64
+	var x20 uint64
+	x19, x20 = bits.Add64(x18, x15, uint64(0x0))
+	var x21 uint64
+	var x22 uint64
+	x21, x22 = bits.Add64(x16, x13, uint64(p384Uint1(x20)))
+	var x23 uint64
+	var x24 uint64
+	x23, x24 = bits.Add64(x14, x11, uint64(p384Uint1(x22)))
+	var x25 uint64
+	var x26 uint64
+	x25, x26 = bits.Add64(x12, x9, uint64(p384Uint1(x24)))
+	var x27 uint64
+	var x28 uint64
+	x27, x28 = bits.Add64(x10, x7, uint64(p384Uint1(x26)))
+	x29 := (uint64(p384Uint1(x28)) + x8)
+	var x30 uint64
+	_, x30 = bits.Mul64(x17, 0x100000001)
+	var x32 uint64
+	var x33 uint64
+	x33, x32 = bits.Mul64(x30, 0xffffffffffffffff)
+	var x34 uint64
+	var x35 uint64
+	x35, x34 = bits.Mul64(x30, 0xffffffffffffffff)
+	var x36 uint64
+	var x37 uint64
+	x37, x36 = bits.Mul64(x30, 0xffffffffffffffff)
+	var x38 uint64
+	var x39 uint64
+	x39, x38 = bits.Mul64(x30, 0xfffffffffffffffe)
+	var x40 uint64
+	var x41 uint64
+	x41, x40 = bits.Mul64(x30, 0xffffffff00000000)
+	var x42 uint64
+	var x43 uint64
+	x43, x42 = bits.Mul64(x30, 0xffffffff)
+	var x44 uint64
+	var x45 uint64
+	x44, x45 = bits.Add64(x43, x40, uint64(0x0))
+	var x46 uint64
+	var x47 uint64
+	x46, x47 = bits.Add64(x41, x38, uint64(p384Uint1(x45)))
+	var x48 uint64
+	var x49 uint64
+	x48, x49 = bits.Add64(x39, x36, uint64(p384Uint1(x47)))
+	var x50 uint64
+	var x51 uint64
+	x50, x51 = bits.Add64(x37, x34, uint64(p384Uint1(x49)))
+	var x52 uint64
+	var x53 uint64
+	x52, x53 = bits.Add64(x35, x32, uint64(p384Uint1(x51)))
+	x54 := (uint64(p384Uint1(x53)) + x33)
+	var x56 uint64
+	_, x56 = bits.Add64(x17, x42, uint64(0x0))
+	var x57 uint64
+	var x58 uint64
+	x57, x58 = bits.Add64(x19, x44, uint64(p384Uint1(x56)))
+	var x59 uint64
+	var x60 uint64
+	x59, x60 = bits.Add64(x21, x46, uint64(p384Uint1(x58)))
+	var x61 uint64
+	var x62 uint64
+	x61, x62 = bits.Add64(x23, x48, uint64(p384Uint1(x60)))
+	var x63 uint64
+	var x64 uint64
+	x63, x64 = bits.Add64(x25, x50, uint64(p384Uint1(x62)))
+	var x65 uint64
+	var x66 uint64
+	x65, x66 = bits.Add64(x27, x52, uint64(p384Uint1(x64)))
+	var x67 uint64
+	var x68 uint64
+	x67, x68 = bits.Add64(x29, x54, uint64(p384Uint1(x66)))
+	var x69 uint64
+	var x70 uint64
+	x70, x69 = bits.Mul64(x1, arg2[5])
+	var x71 uint64
+	var x72 uint64
+	x72, x71 = bits.Mul64(x1, arg2[4])
+	var x73 uint64
+	var x74 uint64
+	x74, x73 = bits.Mul64(x1, arg2[3])
+	var x75 uint64
+	var x76 uint64
+	x76, x75 = bits.Mul64(x1, arg2[2])
+	var x77 uint64
+	var x78 uint64
+	x78, x77 = bits.Mul64(x1, arg2[1])
+	var x79 uint64
+	var x80 uint64
+	x80, x79 = bits.Mul64(x1, arg2[0])
+	var x81 uint64
+	var x82 uint64
+	x81, x82 = bits.Add64(x80, x77, uint64(0x0))
+	var x83 uint64
+	var x84 uint64
+	x83, x84 = bits.Add64(x78, x75, uint64(p384Uint1(x82)))
+	var x85 uint64
+	var x86 uint64
+	x85, x86 = bits.Add64(x76, x73, uint64(p384Uint1(x84)))
+	var x87 uint64
+	var x88 uint64
+	x87, x88 = bits.Add64(x74, x71, uint64(p384Uint1(x86)))
+	var x89 uint64
+	var x90 uint64
+	x89, x90 = bits.Add64(x72, x69, uint64(p384Uint1(x88)))
+	x91 := (uint64(p384Uint1(x90)) + x70)
+	var x92 uint64
+	var x93 uint64
+	x92, x93 = bits.Add64(x57, x79, uint64(0x0))
+	var x94 uint64
+	var x95 uint64
+	x94, x95 = bits.Add64(x59, x81, uint64(p384Uint1(x93)))
+	var x96 uint64
+	var x97 uint64
+	x96, x97 = bits.Add64(x61, x83, uint64(p384Uint1(x95)))
+	var x98 uint64
+	var x99 uint64
+	x98, x99 = bits.Add64(x63, x85, uint64(p384Uint1(x97)))
+	var x100 uint64
+	var x101 uint64
+	x100, x101 = bits.Add64(x65, x87, uint64(p384Uint1(x99)))
+	var x102 uint64
+	var x103 uint64
+	x102, x103 = bits.Add64(x67, x89, uint64(p384Uint1(x101)))
+	var x104 uint64
+	var x105 uint64
+	x104, x105 = bits.Add64(uint64(p384Uint1(x68)), x91, uint64(p384Uint1(x103)))
+	var x106 uint64
+	_, x106 = bits.Mul64(x92, 0x100000001)
+	var x108 uint64
+	var x109 uint64
+	x109, x108 = bits.Mul64(x106, 0xffffffffffffffff)
+	var x110 uint64
+	var x111 uint64
+	x111, x110 = bits.Mul64(x106, 0xffffffffffffffff)
+	var x112 uint64
+	var x113 uint64
+	x113, x112 = bits.Mul64(x106, 0xffffffffffffffff)
+	var x114 uint64
+	var x115 uint64
+	x115, x114 = bits.Mul64(x106, 0xfffffffffffffffe)
+	var x116 uint64
+	var x117 uint64
+	x117, x116 = bits.Mul64(x106, 0xffffffff00000000)
+	var x118 uint64
+	var x119 uint64
+	x119, x118 = bits.Mul64(x106, 0xffffffff)
+	var x120 uint64
+	var x121 uint64
+	x120, x121 = bits.Add64(x119, x116, uint64(0x0))
+	var x122 uint64
+	var x123 uint64
+	x122, x123 = bits.Add64(x117, x114, uint64(p384Uint1(x121)))
+	var x124 uint64
+	var x125 uint64
+	x124, x125 = bits.Add64(x115, x112, uint64(p384Uint1(x123)))
+	var x126 uint64
+	var x127 uint64
+	x126, x127 = bits.Add64(x113, x110, uint64(p384Uint1(x125)))
+	var x128 uint64
+	var x129 uint64
+	x128, x129 = bits.Add64(x111, x108, uint64(p384Uint1(x127)))
+	x130 := (uint64(p384Uint1(x129)) + x109)
+	var x132 uint64
+	_, x132 = bits.Add64(x92, x118, uint64(0x0))
+	var x133 uint64
+	var x134 uint64
+	x133, x134 = bits.Add64(x94, x120, uint64(p384Uint1(x132)))
+	var x135 uint64
+	var x136 uint64
+	x135, x136 = bits.Add64(x96, x122, uint64(p384Uint1(x134)))
+	var x137 uint64
+	var x138 uint64
+	x137, x138 = bits.Add64(x98, x124, uint64(p384Uint1(x136)))
+	var x139 uint64
+	var x140 uint64
+	x139, x140 = bits.Add64(x100, x126, uint64(p384Uint1(x138)))
+	var x141 uint64
+	var x142 uint64
+	x141, x142 = bits.Add64(x102, x128, uint64(p384Uint1(x140)))
+	var x143 uint64
+	var x144 uint64
+	x143, x144 = bits.Add64(x104, x130, uint64(p384Uint1(x142)))
+	x145 := (uint64(p384Uint1(x144)) + uint64(p384Uint1(x105)))
+	var x146 uint64
+	var x147 uint64
+	x147, x146 = bits.Mul64(x2, arg2[5])
+	var x148 uint64
+	var x149 uint64
+	x149, x148 = bits.Mul64(x2, arg2[4])
+	var x150 uint64
+	var x151 uint64
+	x151, x150 = bits.Mul64(x2, arg2[3])
+	var x152 uint64
+	var x153 uint64
+	x153, x152 = bits.Mul64(x2, arg2[2])
+	var x154 uint64
+	var x155 uint64
+	x155, x154 = bits.Mul64(x2, arg2[1])
+	var x156 uint64
+	var x157 uint64
+	x157, x156 = bits.Mul64(x2, arg2[0])
+	var x158 uint64
+	var x159 uint64
+	x158, x159 = bits.Add64(x157, x154, uint64(0x0))
+	var x160 uint64
+	var x161 uint64
+	x160, x161 = bits.Add64(x155, x152, uint64(p384Uint1(x159)))
+	var x162 uint64
+	var x163 uint64
+	x162, x163 = bits.Add64(x153, x150, uint64(p384Uint1(x161)))
+	var x164 uint64
+	var x165 uint64
+	x164, x165 = bits.Add64(x151, x148, uint64(p384Uint1(x163)))
+	var x166 uint64
+	var x167 uint64
+	x166, x167 = bits.Add64(x149, x146, uint64(p384Uint1(x165)))
+	x168 := (uint64(p384Uint1(x167)) + x147)
+	var x169 uint64
+	var x170 uint64
+	x169, x170 = bits.Add64(x133, x156, uint64(0x0))
+	var x171 uint64
+	var x172 uint64
+	x171, x172 = bits.Add64(x135, x158, uint64(p384Uint1(x170)))
+	var x173 uint64
+	var x174 uint64
+	x173, x174 = bits.Add64(x137, x160, uint64(p384Uint1(x172)))
+	var x175 uint64
+	var x176 uint64
+	x175, x176 = bits.Add64(x139, x162, uint64(p384Uint1(x174)))
+	var x177 uint64
+	var x178 uint64
+	x177, x178 = bits.Add64(x141, x164, uint64(p384Uint1(x176)))
+	var x179 uint64
+	var x180 uint64
+	x179, x180 = bits.Add64(x143, x166, uint64(p384Uint1(x178)))
+	var x181 uint64
+	var x182 uint64
+	x181, x182 = bits.Add64(x145, x168, uint64(p384Uint1(x180)))
+	var x183 uint64
+	_, x183 = bits.Mul64(x169, 0x100000001)
+	var x185 uint64
+	var x186 uint64
+	x186, x185 = bits.Mul64(x183, 0xffffffffffffffff)
+	var x187 uint64
+	var x188 uint64
+	x188, x187 = bits.Mul64(x183, 0xffffffffffffffff)
+	var x189 uint64
+	var x190 uint64
+	x190, x189 = bits.Mul64(x183, 0xffffffffffffffff)
+	var x191 uint64
+	var x192 uint64
+	x192, x191 = bits.Mul64(x183, 0xfffffffffffffffe)
+	var x193 uint64
+	var x194 uint64
+	x194, x193 = bits.Mul64(x183, 0xffffffff00000000)
+	var x195 uint64
+	var x196 uint64
+	x196, x195 = bits.Mul64(x183, 0xffffffff)
+	var x197 uint64
+	var x198 uint64
+	x197, x198 = bits.Add64(x196, x193, uint64(0x0))
+	var x199 uint64
+	var x200 uint64
+	x199, x200 = bits.Add64(x194, x191, uint64(p384Uint1(x198)))
+	var x201 uint64
+	var x202 uint64
+	x201, x202 = bits.Add64(x192, x189, uint64(p384Uint1(x200)))
+	var x203 uint64
+	var x204 uint64
+	x203, x204 = bits.Add64(x190, x187, uint64(p384Uint1(x202)))
+	var x205 uint64
+	var x206 uint64
+	x205, x206 = bits.Add64(x188, x185, uint64(p384Uint1(x204)))
+	x207 := (uint64(p384Uint1(x206)) + x186)
+	var x209 uint64
+	_, x209 = bits.Add64(x169, x195, uint64(0x0))
+	var x210 uint64
+	var x211 uint64
+	x210, x211 = bits.Add64(x171, x197, uint64(p384Uint1(x209)))
+	var x212 uint64
+	var x213 uint64
+	x212, x213 = bits.Add64(x173, x199, uint64(p384Uint1(x211)))
+	var x214 uint64
+	var x215 uint64
+	x214, x215 = bits.Add64(x175, x201, uint64(p384Uint1(x213)))
+	var x216 uint64
+	var x217 uint64
+	x216, x217 = bits.Add64(x177, x203, uint64(p384Uint1(x215)))
+	var x218 uint64
+	var x219 uint64
+	x218, x219 = bits.Add64(x179, x205, uint64(p384Uint1(x217)))
+	var x220 uint64
+	var x221 uint64
+	x220, x221 = bits.Add64(x181, x207, uint64(p384Uint1(x219)))
+	x222 := (uint64(p384Uint1(x221)) + uint64(p384Uint1(x182)))
+	var x223 uint64
+	var x224 uint64
+	x224, x223 = bits.Mul64(x3, arg2[5])
+	var x225 uint64
+	var x226 uint64
+	x226, x225 = bits.Mul64(x3, arg2[4])
+	var x227 uint64
+	var x228 uint64
+	x228, x227 = bits.Mul64(x3, arg2[3])
+	var x229 uint64
+	var x230 uint64
+	x230, x229 = bits.Mul64(x3, arg2[2])
+	var x231 uint64
+	var x232 uint64
+	x232, x231 = bits.Mul64(x3, arg2[1])
+	var x233 uint64
+	var x234 uint64
+	x234, x233 = bits.Mul64(x3, arg2[0])
+	var x235 uint64
+	var x236 uint64
+	x235, x236 = bits.Add64(x234, x231, uint64(0x0))
+	var x237 uint64
+	var x238 uint64
+	x237, x238 = bits.Add64(x232, x229, uint64(p384Uint1(x236)))
+	var x239 uint64
+	var x240 uint64
+	x239, x240 = bits.Add64(x230, x227, uint64(p384Uint1(x238)))
+	var x241 uint64
+	var x242 uint64
+	x241, x242 = bits.Add64(x228, x225, uint64(p384Uint1(x240)))
+	var x243 uint64
+	var x244 uint64
+	x243, x244 = bits.Add64(x226, x223, uint64(p384Uint1(x242)))
+	x245 := (uint64(p384Uint1(x244)) + x224)
+	var x246 uint64
+	var x247 uint64
+	x246, x247 = bits.Add64(x210, x233, uint64(0x0))
+	var x248 uint64
+	var x249 uint64
+	x248, x249 = bits.Add64(x212, x235, uint64(p384Uint1(x247)))
+	var x250 uint64
+	var x251 uint64
+	x250, x251 = bits.Add64(x214, x237, uint64(p384Uint1(x249)))
+	var x252 uint64
+	var x253 uint64
+	x252, x253 = bits.Add64(x216, x239, uint64(p384Uint1(x251)))
+	var x254 uint64
+	var x255 uint64
+	x254, x255 = bits.Add64(x218, x241, uint64(p384Uint1(x253)))
+	var x256 uint64
+	var x257 uint64
+	x256, x257 = bits.Add64(x220, x243, uint64(p384Uint1(x255)))
+	var x258 uint64
+	var x259 uint64
+	x258, x259 = bits.Add64(x222, x245, uint64(p384Uint1(x257)))
+	var x260 uint64
+	_, x260 = bits.Mul64(x246, 0x100000001)
+	var x262 uint64
+	var x263 uint64
+	x263, x262 = bits.Mul64(x260, 0xffffffffffffffff)
+	var x264 uint64
+	var x265 uint64
+	x265, x264 = bits.Mul64(x260, 0xffffffffffffffff)
+	var x266 uint64
+	var x267 uint64
+	x267, x266 = bits.Mul64(x260, 0xffffffffffffffff)
+	var x268 uint64
+	var x269 uint64
+	x269, x268 = bits.Mul64(x260, 0xfffffffffffffffe)
+	var x270 uint64
+	var x271 uint64
+	x271, x270 = bits.Mul64(x260, 0xffffffff00000000)
+	var x272 uint64
+	var x273 uint64
+	x273, x272 = bits.Mul64(x260, 0xffffffff)
+	var x274 uint64
+	var x275 uint64
+	x274, x275 = bits.Add64(x273, x270, uint64(0x0))
+	var x276 uint64
+	var x277 uint64
+	x276, x277 = bits.Add64(x271, x268, uint64(p384Uint1(x275)))
+	var x278 uint64
+	var x279 uint64
+	x278, x279 = bits.Add64(x269, x266, uint64(p384Uint1(x277)))
+	var x280 uint64
+	var x281 uint64
+	x280, x281 = bits.Add64(x267, x264, uint64(p384Uint1(x279)))
+	var x282 uint64
+	var x283 uint64
+	x282, x283 = bits.Add64(x265, x262, uint64(p384Uint1(x281)))
+	x284 := (uint64(p384Uint1(x283)) + x263)
+	var x286 uint64
+	_, x286 = bits.Add64(x246, x272, uint64(0x0))
+	var x287 uint64
+	var x288 uint64
+	x287, x288 = bits.Add64(x248, x274, uint64(p384Uint1(x286)))
+	var x289 uint64
+	var x290 uint64
+	x289, x290 = bits.Add64(x250, x276, uint64(p384Uint1(x288)))
+	var x291 uint64
+	var x292 uint64
+	x291, x292 = bits.Add64(x252, x278, uint64(p384Uint1(x290)))
+	var x293 uint64
+	var x294 uint64
+	x293, x294 = bits.Add64(x254, x280, uint64(p384Uint1(x292)))
+	var x295 uint64
+	var x296 uint64
+	x295, x296 = bits.Add64(x256, x282, uint64(p384Uint1(x294)))
+	var x297 uint64
+	var x298 uint64
+	x297, x298 = bits.Add64(x258, x284, uint64(p384Uint1(x296)))
+	x299 := (uint64(p384Uint1(x298)) + uint64(p384Uint1(x259)))
+	var x300 uint64
+	var x301 uint64
+	x301, x300 = bits.Mul64(x4, arg2[5])
+	var x302 uint64
+	var x303 uint64
+	x303, x302 = bits.Mul64(x4, arg2[4])
+	var x304 uint64
+	var x305 uint64
+	x305, x304 = bits.Mul64(x4, arg2[3])
+	var x306 uint64
+	var x307 uint64
+	x307, x306 = bits.Mul64(x4, arg2[2])
+	var x308 uint64
+	var x309 uint64
+	x309, x308 = bits.Mul64(x4, arg2[1])
+	var x310 uint64
+	var x311 uint64
+	x311, x310 = bits.Mul64(x4, arg2[0])
+	var x312 uint64
+	var x313 uint64
+	x312, x313 = bits.Add64(x311, x308, uint64(0x0))
+	var x314 uint64
+	var x315 uint64
+	x314, x315 = bits.Add64(x309, x306, uint64(p384Uint1(x313)))
+	var x316 uint64
+	var x317 uint64
+	x316, x317 = bits.Add64(x307, x304, uint64(p384Uint1(x315)))
+	var x318 uint64
+	var x319 uint64
+	x318, x319 = bits.Add64(x305, x302, uint64(p384Uint1(x317)))
+	var x320 uint64
+	var x321 uint64
+	x320, x321 = bits.Add64(x303, x300, uint64(p384Uint1(x319)))
+	x322 := (uint64(p384Uint1(x321)) + x301)
+	var x323 uint64
+	var x324 uint64
+	x323, x324 = bits.Add64(x287, x310, uint64(0x0))
+	var x325 uint64
+	var x326 uint64
+	x325, x326 = bits.Add64(x289, x312, uint64(p384Uint1(x324)))
+	var x327 uint64
+	var x328 uint64
+	x327, x328 = bits.Add64(x291, x314, uint64(p384Uint1(x326)))
+	var x329 uint64
+	var x330 uint64
+	x329, x330 = bits.Add64(x293, x316, uint64(p384Uint1(x328)))
+	var x331 uint64
+	var x332 uint64
+	x331, x332 = bits.Add64(x295, x318, uint64(p384Uint1(x330)))
+	var x333 uint64
+	var x334 uint64
+	x333, x334 = bits.Add64(x297, x320, uint64(p384Uint1(x332)))
+	var x335 uint64
+	var x336 uint64
+	x335, x336 = bits.Add64(x299, x322, uint64(p384Uint1(x334)))
+	var x337 uint64
+	_, x337 = bits.Mul64(x323, 0x100000001)
+	var x339 uint64
+	var x340 uint64
+	x340, x339 = bits.Mul64(x337, 0xffffffffffffffff)
+	var x341 uint64
+	var x342 uint64
+	x342, x341 = bits.Mul64(x337, 0xffffffffffffffff)
+	var x343 uint64
+	var x344 uint64
+	x344, x343 = bits.Mul64(x337, 0xffffffffffffffff)
+	var x345 uint64
+	var x346 uint64
+	x346, x345 = bits.Mul64(x337, 0xfffffffffffffffe)
+	var x347 uint64
+	var x348 uint64
+	x348, x347 = bits.Mul64(x337, 0xffffffff00000000)
+	var x349 uint64
+	var x350 uint64
+	x350, x349 = bits.Mul64(x337, 0xffffffff)
+	var x351 uint64
+	var x352 uint64
+	x351, x352 = bits.Add64(x350, x347, uint64(0x0))
+	var x353 uint64
+	var x354 uint64
+	x353, x354 = bits.Add64(x348, x345, uint64(p384Uint1(x352)))
+	var x355 uint64
+	var x356 uint64
+	x355, x356 = bits.Add64(x346, x343, uint64(p384Uint1(x354)))
+	var x357 uint64
+	var x358 uint64
+	x357, x358 = bits.Add64(x344, x341, uint64(p384Uint1(x356)))
+	var x359 uint64
+	var x360 uint64
+	x359, x360 = bits.Add64(x342, x339, uint64(p384Uint1(x358)))
+	x361 := (uint64(p384Uint1(x360)) + x340)
+	var x363 uint64
+	_, x363 = bits.Add64(x323, x349, uint64(0x0))
+	var x364 uint64
+	var x365 uint64
+	x364, x365 = bits.Add64(x325, x351, uint64(p384Uint1(x363)))
+	var x366 uint64
+	var x367 uint64
+	x366, x367 = bits.Add64(x327, x353, uint64(p384Uint1(x365)))
+	var x368 uint64
+	var x369 uint64
+	x368, x369 = bits.Add64(x329, x355, uint64(p384Uint1(x367)))
+	var x370 uint64
+	var x371 uint64
+	x370, x371 = bits.Add64(x331, x357, uint64(p384Uint1(x369)))
+	var x372 uint64
+	var x373 uint64
+	x372, x373 = bits.Add64(x333, x359, uint64(p384Uint1(x371)))
+	var x374 uint64
+	var x375 uint64
+	x374, x375 = bits.Add64(x335, x361, uint64(p384Uint1(x373)))
+	x376 := (uint64(p384Uint1(x375)) + uint64(p384Uint1(x336)))
+	var x377 uint64
+	var x378 uint64
+	x378, x377 = bits.Mul64(x5, arg2[5])
+	var x379 uint64
+	var x380 uint64
+	x380, x379 = bits.Mul64(x5, arg2[4])
+	var x381 uint64
+	var x382 uint64
+	x382, x381 = bits.Mul64(x5, arg2[3])
+	var x383 uint64
+	var x384 uint64
+	x384, x383 = bits.Mul64(x5, arg2[2])
+	var x385 uint64
+	var x386 uint64
+	x386, x385 = bits.Mul64(x5, arg2[1])
+	var x387 uint64
+	var x388 uint64
+	x388, x387 = bits.Mul64(x5, arg2[0])
+	var x389 uint64
+	var x390 uint64
+	x389, x390 = bits.Add64(x388, x385, uint64(0x0))
+	var x391 uint64
+	var x392 uint64
+	x391, x392 = bits.Add64(x386, x383, uint64(p384Uint1(x390)))
+	var x393 uint64
+	var x394 uint64
+	x393, x394 = bits.Add64(x384, x381, uint64(p384Uint1(x392)))
+	var x395 uint64
+	var x396 uint64
+	x395, x396 = bits.Add64(x382, x379, uint64(p384Uint1(x394)))
+	var x397 uint64
+	var x398 uint64
+	x397, x398 = bits.Add64(x380, x377, uint64(p384Uint1(x396)))
+	x399 := (uint64(p384Uint1(x398)) + x378)
+	var x400 uint64
+	var x401 uint64
+	x400, x401 = bits.Add64(x364, x387, uint64(0x0))
+	var x402 uint64
+	var x403 uint64
+	x402, x403 = bits.Add64(x366, x389, uint64(p384Uint1(x401)))
+	var x404 uint64
+	var x405 uint64
+	x404, x405 = bits.Add64(x368, x391, uint64(p384Uint1(x403)))
+	var x406 uint64
+	var x407 uint64
+	x406, x407 = bits.Add64(x370, x393, uint64(p384Uint1(x405)))
+	var x408 uint64
+	var x409 uint64
+	x408, x409 = bits.Add64(x372, x395, uint64(p384Uint1(x407)))
+	var x410 uint64
+	var x411 uint64
+	x410, x411 = bits.Add64(x374, x397, uint64(p384Uint1(x409)))
+	var x412 uint64
+	var x413 uint64
+	x412, x413 = bits.Add64(x376, x399, uint64(p384Uint1(x411)))
+	var x414 uint64
+	_, x414 = bits.Mul64(x400, 0x100000001)
+	var x416 uint64
+	var x417 uint64
+	x417, x416 = bits.Mul64(x414, 0xffffffffffffffff)
+	var x418 uint64
+	var x419 uint64
+	x419, x418 = bits.Mul64(x414, 0xffffffffffffffff)
+	var x420 uint64
+	var x421 uint64
+	x421, x420 = bits.Mul64(x414, 0xffffffffffffffff)
+	var x422 uint64
+	var x423 uint64
+	x423, x422 = bits.Mul64(x414, 0xfffffffffffffffe)
+	var x424 uint64
+	var x425 uint64
+	x425, x424 = bits.Mul64(x414, 0xffffffff00000000)
+	var x426 uint64
+	var x427 uint64
+	x427, x426 = bits.Mul64(x414, 0xffffffff)
+	var x428 uint64
+	var x429 uint64
+	x428, x429 = bits.Add64(x427, x424, uint64(0x0))
+	var x430 uint64
+	var x431 uint64
+	x430, x431 = bits.Add64(x425, x422, uint64(p384Uint1(x429)))
+	var x432 uint64
+	var x433 uint64
+	x432, x433 = bits.Add64(x423, x420, uint64(p384Uint1(x431)))
+	var x434 uint64
+	var x435 uint64
+	x434, x435 = bits.Add64(x421, x418, uint64(p384Uint1(x433)))
+	var x436 uint64
+	var x437 uint64
+	x436, x437 = bits.Add64(x419, x416, uint64(p384Uint1(x435)))
+	x438 := (uint64(p384Uint1(x437)) + x417)
+	var x440 uint64
+	_, x440 = bits.Add64(x400, x426, uint64(0x0))
+	var x441 uint64
+	var x442 uint64
+	x441, x442 = bits.Add64(x402, x428, uint64(p384Uint1(x440)))
+	var x443 uint64
+	var x444 uint64
+	x443, x444 = bits.Add64(x404, x430, uint64(p384Uint1(x442)))
+	var x445 uint64
+	var x446 uint64
+	x445, x446 = bits.Add64(x406, x432, uint64(p384Uint1(x444)))
+	var x447 uint64
+	var x448 uint64
+	x447, x448 = bits.Add64(x408, x434, uint64(p384Uint1(x446)))
+	var x449 uint64
+	var x450 uint64
+	x449, x450 = bits.Add64(x410, x436, uint64(p384Uint1(x448)))
+	var x451 uint64
+	var x452 uint64
+	x451, x452 = bits.Add64(x412, x438, uint64(p384Uint1(x450)))
+	x453 := (uint64(p384Uint1(x452)) + uint64(p384Uint1(x413)))
+	var x454 uint64
+	var x455 uint64
+	x454, x455 = bits.Sub64(x441, 0xffffffff, uint64(0x0))
+	var x456 uint64
+	var x457 uint64
+	x456, x457 = bits.Sub64(x443, 0xffffffff00000000, uint64(p384Uint1(x455)))
+	var x458 uint64
+	var x459 uint64
+	x458, x459 = bits.Sub64(x445, 0xfffffffffffffffe, uint64(p384Uint1(x457)))
+	var x460 uint64
+	var x461 uint64
+	x460, x461 = bits.Sub64(x447, 0xffffffffffffffff, uint64(p384Uint1(x459)))
+	var x462 uint64
+	var x463 uint64
+	x462, x463 = bits.Sub64(x449, 0xffffffffffffffff, uint64(p384Uint1(x461)))
+	var x464 uint64
+	var x465 uint64
+	x464, x465 = bits.Sub64(x451, 0xffffffffffffffff, uint64(p384Uint1(x463)))
+	var x467 uint64
+	_, x467 = bits.Sub64(x453, uint64(0x0), uint64(p384Uint1(x465)))
+	var x468 uint64
+	p384CmovznzU64(&x468, p384Uint1(x467), x454, x441)
+	var x469 uint64
+	p384CmovznzU64(&x469, p384Uint1(x467), x456, x443)
+	var x470 uint64
+	p384CmovznzU64(&x470, p384Uint1(x467), x458, x445)
+	var x471 uint64
+	p384CmovznzU64(&x471, p384Uint1(x467), x460, x447)
+	var x472 uint64
+	p384CmovznzU64(&x472, p384Uint1(x467), x462, x449)
+	var x473 uint64
+	p384CmovznzU64(&x473, p384Uint1(x467), x464, x451)
+	out1[0] = x468
+	out1[1] = x469
+	out1[2] = x470
+	out1[3] = x471
+	out1[4] = x472
+	out1[5] = x473
+}
+
+// p384Square squares a field element in the Montgomery domain.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//
+// Postconditions:
+//
+//	eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) * eval (from_montgomery arg1)) mod m
+//	0 ≤ eval out1 < m
+func p384Square(out1 *p384MontgomeryDomainFieldElement, arg1 *p384MontgomeryDomainFieldElement) {
+	x1 := arg1[1]
+	x2 := arg1[2]
+	x3 := arg1[3]
+	x4 := arg1[4]
+	x5 := arg1[5]
+	x6 := arg1[0]
+	var x7 uint64
+	var x8 uint64
+	x8, x7 = bits.Mul64(x6, arg1[5])
+	var x9 uint64
+	var x10 uint64
+	x10, x9 = bits.Mul64(x6, arg1[4])
+	var x11 uint64
+	var x12 uint64
+	x12, x11 = bits.Mul64(x6, arg1[3])
+	var x13 uint64
+	var x14 uint64
+	x14, x13 = bits.Mul64(x6, arg1[2])
+	var x15 uint64
+	var x16 uint64
+	x16, x15 = bits.Mul64(x6, arg1[1])
+	var x17 uint64
+	var x18 uint64
+	x18, x17 = bits.Mul64(x6, arg1[0])
+	var x19 uint64
+	var x20 uint64
+	x19, x20 = bits.Add64(x18, x15, uint64(0x0))
+	var x21 uint64
+	var x22 uint64
+	x21, x22 = bits.Add64(x16, x13, uint64(p384Uint1(x20)))
+	var x23 uint64
+	var x24 uint64
+	x23, x24 = bits.Add64(x14, x11, uint64(p384Uint1(x22)))
+	var x25 uint64
+	var x26 uint64
+	x25, x26 = bits.Add64(x12, x9, uint64(p384Uint1(x24)))
+	var x27 uint64
+	var x28 uint64
+	x27, x28 = bits.Add64(x10, x7, uint64(p384Uint1(x26)))
+	x29 := (uint64(p384Uint1(x28)) + x8)
+	var x30 uint64
+	_, x30 = bits.Mul64(x17, 0x100000001)
+	var x32 uint64
+	var x33 uint64
+	x33, x32 = bits.Mul64(x30, 0xffffffffffffffff)
+	var x34 uint64
+	var x35 uint64
+	x35, x34 = bits.Mul64(x30, 0xffffffffffffffff)
+	var x36 uint64
+	var x37 uint64
+	x37, x36 = bits.Mul64(x30, 0xffffffffffffffff)
+	var x38 uint64
+	var x39 uint64
+	x39, x38 = bits.Mul64(x30, 0xfffffffffffffffe)
+	var x40 uint64
+	var x41 uint64
+	x41, x40 = bits.Mul64(x30, 0xffffffff00000000)
+	var x42 uint64
+	var x43 uint64
+	x43, x42 = bits.Mul64(x30, 0xffffffff)
+	var x44 uint64
+	var x45 uint64
+	x44, x45 = bits.Add64(x43, x40, uint64(0x0))
+	var x46 uint64
+	var x47 uint64
+	x46, x47 = bits.Add64(x41, x38, uint64(p384Uint1(x45)))
+	var x48 uint64
+	var x49 uint64
+	x48, x49 = bits.Add64(x39, x36, uint64(p384Uint1(x47)))
+	var x50 uint64
+	var x51 uint64
+	x50, x51 = bits.Add64(x37, x34, uint64(p384Uint1(x49)))
+	var x52 uint64
+	var x53 uint64
+	x52, x53 = bits.Add64(x35, x32, uint64(p384Uint1(x51)))
+	x54 := (uint64(p384Uint1(x53)) + x33)
+	var x56 uint64
+	_, x56 = bits.Add64(x17, x42, uint64(0x0))
+	var x57 uint64
+	var x58 uint64
+	x57, x58 = bits.Add64(x19, x44, uint64(p384Uint1(x56)))
+	var x59 uint64
+	var x60 uint64
+	x59, x60 = bits.Add64(x21, x46, uint64(p384Uint1(x58)))
+	var x61 uint64
+	var x62 uint64
+	x61, x62 = bits.Add64(x23, x48, uint64(p384Uint1(x60)))
+	var x63 uint64
+	var x64 uint64
+	x63, x64 = bits.Add64(x25, x50, uint64(p384Uint1(x62)))
+	var x65 uint64
+	var x66 uint64
+	x65, x66 = bits.Add64(x27, x52, uint64(p384Uint1(x64)))
+	var x67 uint64
+	var x68 uint64
+	x67, x68 = bits.Add64(x29, x54, uint64(p384Uint1(x66)))
+	var x69 uint64
+	var x70 uint64
+	x70, x69 = bits.Mul64(x1, arg1[5])
+	var x71 uint64
+	var x72 uint64
+	x72, x71 = bits.Mul64(x1, arg1[4])
+	var x73 uint64
+	var x74 uint64
+	x74, x73 = bits.Mul64(x1, arg1[3])
+	var x75 uint64
+	var x76 uint64
+	x76, x75 = bits.Mul64(x1, arg1[2])
+	var x77 uint64
+	var x78 uint64
+	x78, x77 = bits.Mul64(x1, arg1[1])
+	var x79 uint64
+	var x80 uint64
+	x80, x79 = bits.Mul64(x1, arg1[0])
+	var x81 uint64
+	var x82 uint64
+	x81, x82 = bits.Add64(x80, x77, uint64(0x0))
+	var x83 uint64
+	var x84 uint64
+	x83, x84 = bits.Add64(x78, x75, uint64(p384Uint1(x82)))
+	var x85 uint64
+	var x86 uint64
+	x85, x86 = bits.Add64(x76, x73, uint64(p384Uint1(x84)))
+	var x87 uint64
+	var x88 uint64
+	x87, x88 = bits.Add64(x74, x71, uint64(p384Uint1(x86)))
+	var x89 uint64
+	var x90 uint64
+	x89, x90 = bits.Add64(x72, x69, uint64(p384Uint1(x88)))
+	x91 := (uint64(p384Uint1(x90)) + x70)
+	var x92 uint64
+	var x93 uint64
+	x92, x93 = bits.Add64(x57, x79, uint64(0x0))
+	var x94 uint64
+	var x95 uint64
+	x94, x95 = bits.Add64(x59, x81, uint64(p384Uint1(x93)))
+	var x96 uint64
+	var x97 uint64
+	x96, x97 = bits.Add64(x61, x83, uint64(p384Uint1(x95)))
+	var x98 uint64
+	var x99 uint64
+	x98, x99 = bits.Add64(x63, x85, uint64(p384Uint1(x97)))
+	var x100 uint64
+	var x101 uint64
+	x100, x101 = bits.Add64(x65, x87, uint64(p384Uint1(x99)))
+	var x102 uint64
+	var x103 uint64
+	x102, x103 = bits.Add64(x67, x89, uint64(p384Uint1(x101)))
+	var x104 uint64
+	var x105 uint64
+	x104, x105 = bits.Add64(uint64(p384Uint1(x68)), x91, uint64(p384Uint1(x103)))
+	var x106 uint64
+	_, x106 = bits.Mul64(x92, 0x100000001)
+	var x108 uint64
+	var x109 uint64
+	x109, x108 = bits.Mul64(x106, 0xffffffffffffffff)
+	var x110 uint64
+	var x111 uint64
+	x111, x110 = bits.Mul64(x106, 0xffffffffffffffff)
+	var x112 uint64
+	var x113 uint64
+	x113, x112 = bits.Mul64(x106, 0xffffffffffffffff)
+	var x114 uint64
+	var x115 uint64
+	x115, x114 = bits.Mul64(x106, 0xfffffffffffffffe)
+	var x116 uint64
+	var x117 uint64
+	x117, x116 = bits.Mul64(x106, 0xffffffff00000000)
+	var x118 uint64
+	var x119 uint64
+	x119, x118 = bits.Mul64(x106, 0xffffffff)
+	var x120 uint64
+	var x121 uint64
+	x120, x121 = bits.Add64(x119, x116, uint64(0x0))
+	var x122 uint64
+	var x123 uint64
+	x122, x123 = bits.Add64(x117, x114, uint64(p384Uint1(x121)))
+	var x124 uint64
+	var x125 uint64
+	x124, x125 = bits.Add64(x115, x112, uint64(p384Uint1(x123)))
+	var x126 uint64
+	var x127 uint64
+	x126, x127 = bits.Add64(x113, x110, uint64(p384Uint1(x125)))
+	var x128 uint64
+	var x129 uint64
+	x128, x129 = bits.Add64(x111, x108, uint64(p384Uint1(x127)))
+	x130 := (uint64(p384Uint1(x129)) + x109)
+	var x132 uint64
+	_, x132 = bits.Add64(x92, x118, uint64(0x0))
+	var x133 uint64
+	var x134 uint64
+	x133, x134 = bits.Add64(x94, x120, uint64(p384Uint1(x132)))
+	var x135 uint64
+	var x136 uint64
+	x135, x136 = bits.Add64(x96, x122, uint64(p384Uint1(x134)))
+	var x137 uint64
+	var x138 uint64
+	x137, x138 = bits.Add64(x98, x124, uint64(p384Uint1(x136)))
+	var x139 uint64
+	var x140 uint64
+	x139, x140 = bits.Add64(x100, x126, uint64(p384Uint1(x138)))
+	var x141 uint64
+	var x142 uint64
+	x141, x142 = bits.Add64(x102, x128, uint64(p384Uint1(x140)))
+	var x143 uint64
+	var x144 uint64
+	x143, x144 = bits.Add64(x104, x130, uint64(p384Uint1(x142)))
+	x145 := (uint64(p384Uint1(x144)) + uint64(p384Uint1(x105)))
+	var x146 uint64
+	var x147 uint64
+	x147, x146 = bits.Mul64(x2, arg1[5])
+	var x148 uint64
+	var x149 uint64
+	x149, x148 = bits.Mul64(x2, arg1[4])
+	var x150 uint64
+	var x151 uint64
+	x151, x150 = bits.Mul64(x2, arg1[3])
+	var x152 uint64
+	var x153 uint64
+	x153, x152 = bits.Mul64(x2, arg1[2])
+	var x154 uint64
+	var x155 uint64
+	x155, x154 = bits.Mul64(x2, arg1[1])
+	var x156 uint64
+	var x157 uint64
+	x157, x156 = bits.Mul64(x2, arg1[0])
+	var x158 uint64
+	var x159 uint64
+	x158, x159 = bits.Add64(x157, x154, uint64(0x0))
+	var x160 uint64
+	var x161 uint64
+	x160, x161 = bits.Add64(x155, x152, uint64(p384Uint1(x159)))
+	var x162 uint64
+	var x163 uint64
+	x162, x163 = bits.Add64(x153, x150, uint64(p384Uint1(x161)))
+	var x164 uint64
+	var x165 uint64
+	x164, x165 = bits.Add64(x151, x148, uint64(p384Uint1(x163)))
+	var x166 uint64
+	var x167 uint64
+	x166, x167 = bits.Add64(x149, x146, uint64(p384Uint1(x165)))
+	x168 := (uint64(p384Uint1(x167)) + x147)
+	var x169 uint64
+	var x170 uint64
+	x169, x170 = bits.Add64(x133, x156, uint64(0x0))
+	var x171 uint64
+	var x172 uint64
+	x171, x172 = bits.Add64(x135, x158, uint64(p384Uint1(x170)))
+	var x173 uint64
+	var x174 uint64
+	x173, x174 = bits.Add64(x137, x160, uint64(p384Uint1(x172)))
+	var x175 uint64
+	var x176 uint64
+	x175, x176 = bits.Add64(x139, x162, uint64(p384Uint1(x174)))
+	var x177 uint64
+	var x178 uint64
+	x177, x178 = bits.Add64(x141, x164, uint64(p384Uint1(x176)))
+	var x179 uint64
+	var x180 uint64
+	x179, x180 = bits.Add64(x143, x166, uint64(p384Uint1(x178)))
+	var x181 uint64
+	var x182 uint64
+	x181, x182 = bits.Add64(x145, x168, uint64(p384Uint1(x180)))
+	var x183 uint64
+	_, x183 = bits.Mul64(x169, 0x100000001)
+	var x185 uint64
+	var x186 uint64
+	x186, x185 = bits.Mul64(x183, 0xffffffffffffffff)
+	var x187 uint64
+	var x188 uint64
+	x188, x187 = bits.Mul64(x183, 0xffffffffffffffff)
+	var x189 uint64
+	var x190 uint64
+	x190, x189 = bits.Mul64(x183, 0xffffffffffffffff)
+	var x191 uint64
+	var x192 uint64
+	x192, x191 = bits.Mul64(x183, 0xfffffffffffffffe)
+	var x193 uint64
+	var x194 uint64
+	x194, x193 = bits.Mul64(x183, 0xffffffff00000000)
+	var x195 uint64
+	var x196 uint64
+	x196, x195 = bits.Mul64(x183, 0xffffffff)
+	var x197 uint64
+	var x198 uint64
+	x197, x198 = bits.Add64(x196, x193, uint64(0x0))
+	var x199 uint64
+	var x200 uint64
+	x199, x200 = bits.Add64(x194, x191, uint64(p384Uint1(x198)))
+	var x201 uint64
+	var x202 uint64
+	x201, x202 = bits.Add64(x192, x189, uint64(p384Uint1(x200)))
+	var x203 uint64
+	var x204 uint64
+	x203, x204 = bits.Add64(x190, x187, uint64(p384Uint1(x202)))
+	var x205 uint64
+	var x206 uint64
+	x205, x206 = bits.Add64(x188, x185, uint64(p384Uint1(x204)))
+	x207 := (uint64(p384Uint1(x206)) + x186)
+	var x209 uint64
+	_, x209 = bits.Add64(x169, x195, uint64(0x0))
+	var x210 uint64
+	var x211 uint64
+	x210, x211 = bits.Add64(x171, x197, uint64(p384Uint1(x209)))
+	var x212 uint64
+	var x213 uint64
+	x212, x213 = bits.Add64(x173, x199, uint64(p384Uint1(x211)))
+	var x214 uint64
+	var x215 uint64
+	x214, x215 = bits.Add64(x175, x201, uint64(p384Uint1(x213)))
+	var x216 uint64
+	var x217 uint64
+	x216, x217 = bits.Add64(x177, x203, uint64(p384Uint1(x215)))
+	var x218 uint64
+	var x219 uint64
+	x218, x219 = bits.Add64(x179, x205, uint64(p384Uint1(x217)))
+	var x220 uint64
+	var x221 uint64
+	x220, x221 = bits.Add64(x181, x207, uint64(p384Uint1(x219)))
+	x222 := (uint64(p384Uint1(x221)) + uint64(p384Uint1(x182)))
+	var x223 uint64
+	var x224 uint64
+	x224, x223 = bits.Mul64(x3, arg1[5])
+	var x225 uint64
+	var x226 uint64
+	x226, x225 = bits.Mul64(x3, arg1[4])
+	var x227 uint64
+	var x228 uint64
+	x228, x227 = bits.Mul64(x3, arg1[3])
+	var x229 uint64
+	var x230 uint64
+	x230, x229 = bits.Mul64(x3, arg1[2])
+	var x231 uint64
+	var x232 uint64
+	x232, x231 = bits.Mul64(x3, arg1[1])
+	var x233 uint64
+	var x234 uint64
+	x234, x233 = bits.Mul64(x3, arg1[0])
+	var x235 uint64
+	var x236 uint64
+	x235, x236 = bits.Add64(x234, x231, uint64(0x0))
+	var x237 uint64
+	var x238 uint64
+	x237, x238 = bits.Add64(x232, x229, uint64(p384Uint1(x236)))
+	var x239 uint64
+	var x240 uint64
+	x239, x240 = bits.Add64(x230, x227, uint64(p384Uint1(x238)))
+	var x241 uint64
+	var x242 uint64
+	x241, x242 = bits.Add64(x228, x225, uint64(p384Uint1(x240)))
+	var x243 uint64
+	var x244 uint64
+	x243, x244 = bits.Add64(x226, x223, uint64(p384Uint1(x242)))
+	x245 := (uint64(p384Uint1(x244)) + x224)
+	var x246 uint64
+	var x247 uint64
+	x246, x247 = bits.Add64(x210, x233, uint64(0x0))
+	var x248 uint64
+	var x249 uint64
+	x248, x249 = bits.Add64(x212, x235, uint64(p384Uint1(x247)))
+	var x250 uint64
+	var x251 uint64
+	x250, x251 = bits.Add64(x214, x237, uint64(p384Uint1(x249)))
+	var x252 uint64
+	var x253 uint64
+	x252, x253 = bits.Add64(x216, x239, uint64(p384Uint1(x251)))
+	var x254 uint64
+	var x255 uint64
+	x254, x255 = bits.Add64(x218, x241, uint64(p384Uint1(x253)))
+	var x256 uint64
+	var x257 uint64
+	x256, x257 = bits.Add64(x220, x243, uint64(p384Uint1(x255)))
+	var x258 uint64
+	var x259 uint64
+	x258, x259 = bits.Add64(x222, x245, uint64(p384Uint1(x257)))
+	var x260 uint64
+	_, x260 = bits.Mul64(x246, 0x100000001)
+	var x262 uint64
+	var x263 uint64
+	x263, x262 = bits.Mul64(x260, 0xffffffffffffffff)
+	var x264 uint64
+	var x265 uint64
+	x265, x264 = bits.Mul64(x260, 0xffffffffffffffff)
+	var x266 uint64
+	var x267 uint64
+	x267, x266 = bits.Mul64(x260, 0xffffffffffffffff)
+	var x268 uint64
+	var x269 uint64
+	x269, x268 = bits.Mul64(x260, 0xfffffffffffffffe)
+	var x270 uint64
+	var x271 uint64
+	x271, x270 = bits.Mul64(x260, 0xffffffff00000000)
+	var x272 uint64
+	var x273 uint64
+	x273, x272 = bits.Mul64(x260, 0xffffffff)
+	var x274 uint64
+	var x275 uint64
+	x274, x275 = bits.Add64(x273, x270, uint64(0x0))
+	var x276 uint64
+	var x277 uint64
+	x276, x277 = bits.Add64(x271, x268, uint64(p384Uint1(x275)))
+	var x278 uint64
+	var x279 uint64
+	x278, x279 = bits.Add64(x269, x266, uint64(p384Uint1(x277)))
+	var x280 uint64
+	var x281 uint64
+	x280, x281 = bits.Add64(x267, x264, uint64(p384Uint1(x279)))
+	var x282 uint64
+	var x283 uint64
+	x282, x283 = bits.Add64(x265, x262, uint64(p384Uint1(x281)))
+	x284 := (uint64(p384Uint1(x283)) + x263)
+	var x286 uint64
+	_, x286 = bits.Add64(x246, x272, uint64(0x0))
+	var x287 uint64
+	var x288 uint64
+	x287, x288 = bits.Add64(x248, x274, uint64(p384Uint1(x286)))
+	var x289 uint64
+	var x290 uint64
+	x289, x290 = bits.Add64(x250, x276, uint64(p384Uint1(x288)))
+	var x291 uint64
+	var x292 uint64
+	x291, x292 = bits.Add64(x252, x278, uint64(p384Uint1(x290)))
+	var x293 uint64
+	var x294 uint64
+	x293, x294 = bits.Add64(x254, x280, uint64(p384Uint1(x292)))
+	var x295 uint64
+	var x296 uint64
+	x295, x296 = bits.Add64(x256, x282, uint64(p384Uint1(x294)))
+	var x297 uint64
+	var x298 uint64
+	x297, x298 = bits.Add64(x258, x284, uint64(p384Uint1(x296)))
+	x299 := (uint64(p384Uint1(x298)) + uint64(p384Uint1(x259)))
+	var x300 uint64
+	var x301 uint64
+	x301, x300 = bits.Mul64(x4, arg1[5])
+	var x302 uint64
+	var x303 uint64
+	x303, x302 = bits.Mul64(x4, arg1[4])
+	var x304 uint64
+	var x305 uint64
+	x305, x304 = bits.Mul64(x4, arg1[3])
+	var x306 uint64
+	var x307 uint64
+	x307, x306 = bits.Mul64(x4, arg1[2])
+	var x308 uint64
+	var x309 uint64
+	x309, x308 = bits.Mul64(x4, arg1[1])
+	var x310 uint64
+	var x311 uint64
+	x311, x310 = bits.Mul64(x4, arg1[0])
+	var x312 uint64
+	var x313 uint64
+	x312, x313 = bits.Add64(x311, x308, uint64(0x0))
+	var x314 uint64
+	var x315 uint64
+	x314, x315 = bits.Add64(x309, x306, uint64(p384Uint1(x313)))
+	var x316 uint64
+	var x317 uint64
+	x316, x317 = bits.Add64(x307, x304, uint64(p384Uint1(x315)))
+	var x318 uint64
+	var x319 uint64
+	x318, x319 = bits.Add64(x305, x302, uint64(p384Uint1(x317)))
+	var x320 uint64
+	var x321 uint64
+	x320, x321 = bits.Add64(x303, x300, uint64(p384Uint1(x319)))
+	x322 := (uint64(p384Uint1(x321)) + x301)
+	var x323 uint64
+	var x324 uint64
+	x323, x324 = bits.Add64(x287, x310, uint64(0x0))
+	var x325 uint64
+	var x326 uint64
+	x325, x326 = bits.Add64(x289, x312, uint64(p384Uint1(x324)))
+	var x327 uint64
+	var x328 uint64
+	x327, x328 = bits.Add64(x291, x314, uint64(p384Uint1(x326)))
+	var x329 uint64
+	var x330 uint64
+	x329, x330 = bits.Add64(x293, x316, uint64(p384Uint1(x328)))
+	var x331 uint64
+	var x332 uint64
+	x331, x332 = bits.Add64(x295, x318, uint64(p384Uint1(x330)))
+	var x333 uint64
+	var x334 uint64
+	x333, x334 = bits.Add64(x297, x320, uint64(p384Uint1(x332)))
+	var x335 uint64
+	var x336 uint64
+	x335, x336 = bits.Add64(x299, x322, uint64(p384Uint1(x334)))
+	var x337 uint64
+	_, x337 = bits.Mul64(x323, 0x100000001)
+	var x339 uint64
+	var x340 uint64
+	x340, x339 = bits.Mul64(x337, 0xffffffffffffffff)
+	var x341 uint64
+	var x342 uint64
+	x342, x341 = bits.Mul64(x337, 0xffffffffffffffff)
+	var x343 uint64
+	var x344 uint64
+	x344, x343 = bits.Mul64(x337, 0xffffffffffffffff)
+	var x345 uint64
+	var x346 uint64
+	x346, x345 = bits.Mul64(x337, 0xfffffffffffffffe)
+	var x347 uint64
+	var x348 uint64
+	x348, x347 = bits.Mul64(x337, 0xffffffff00000000)
+	var x349 uint64
+	var x350 uint64
+	x350, x349 = bits.Mul64(x337, 0xffffffff)
+	var x351 uint64
+	var x352 uint64
+	x351, x352 = bits.Add64(x350, x347, uint64(0x0))
+	var x353 uint64
+	var x354 uint64
+	x353, x354 = bits.Add64(x348, x345, uint64(p384Uint1(x352)))
+	var x355 uint64
+	var x356 uint64
+	x355, x356 = bits.Add64(x346, x343, uint64(p384Uint1(x354)))
+	var x357 uint64
+	var x358 uint64
+	x357, x358 = bits.Add64(x344, x341, uint64(p384Uint1(x356)))
+	var x359 uint64
+	var x360 uint64
+	x359, x360 = bits.Add64(x342, x339, uint64(p384Uint1(x358)))
+	x361 := (uint64(p384Uint1(x360)) + x340)
+	var x363 uint64
+	_, x363 = bits.Add64(x323, x349, uint64(0x0))
+	var x364 uint64
+	var x365 uint64
+	x364, x365 = bits.Add64(x325, x351, uint64(p384Uint1(x363)))
+	var x366 uint64
+	var x367 uint64
+	x366, x367 = bits.Add64(x327, x353, uint64(p384Uint1(x365)))
+	var x368 uint64
+	var x369 uint64
+	x368, x369 = bits.Add64(x329, x355, uint64(p384Uint1(x367)))
+	var x370 uint64
+	var x371 uint64
+	x370, x371 = bits.Add64(x331, x357, uint64(p384Uint1(x369)))
+	var x372 uint64
+	var x373 uint64
+	x372, x373 = bits.Add64(x333, x359, uint64(p384Uint1(x371)))
+	var x374 uint64
+	var x375 uint64
+	x374, x375 = bits.Add64(x335, x361, uint64(p384Uint1(x373)))
+	x376 := (uint64(p384Uint1(x375)) + uint64(p384Uint1(x336)))
+	var x377 uint64
+	var x378 uint64
+	x378, x377 = bits.Mul64(x5, arg1[5])
+	var x379 uint64
+	var x380 uint64
+	x380, x379 = bits.Mul64(x5, arg1[4])
+	var x381 uint64
+	var x382 uint64
+	x382, x381 = bits.Mul64(x5, arg1[3])
+	var x383 uint64
+	var x384 uint64
+	x384, x383 = bits.Mul64(x5, arg1[2])
+	var x385 uint64
+	var x386 uint64
+	x386, x385 = bits.Mul64(x5, arg1[1])
+	var x387 uint64
+	var x388 uint64
+	x388, x387 = bits.Mul64(x5, arg1[0])
+	var x389 uint64
+	var x390 uint64
+	x389, x390 = bits.Add64(x388, x385, uint64(0x0))
+	var x391 uint64
+	var x392 uint64
+	x391, x392 = bits.Add64(x386, x383, uint64(p384Uint1(x390)))
+	var x393 uint64
+	var x394 uint64
+	x393, x394 = bits.Add64(x384, x381, uint64(p384Uint1(x392)))
+	var x395 uint64
+	var x396 uint64
+	x395, x396 = bits.Add64(x382, x379, uint64(p384Uint1(x394)))
+	var x397 uint64
+	var x398 uint64
+	x397, x398 = bits.Add64(x380, x377, uint64(p384Uint1(x396)))
+	x399 := (uint64(p384Uint1(x398)) + x378)
+	var x400 uint64
+	var x401 uint64
+	x400, x401 = bits.Add64(x364, x387, uint64(0x0))
+	var x402 uint64
+	var x403 uint64
+	x402, x403 = bits.Add64(x366, x389, uint64(p384Uint1(x401)))
+	var x404 uint64
+	var x405 uint64
+	x404, x405 = bits.Add64(x368, x391, uint64(p384Uint1(x403)))
+	var x406 uint64
+	var x407 uint64
+	x406, x407 = bits.Add64(x370, x393, uint64(p384Uint1(x405)))
+	var x408 uint64
+	var x409 uint64
+	x408, x409 = bits.Add64(x372, x395, uint64(p384Uint1(x407)))
+	var x410 uint64
+	var x411 uint64
+	x410, x411 = bits.Add64(x374, x397, uint64(p384Uint1(x409)))
+	var x412 uint64
+	var x413 uint64
+	x412, x413 = bits.Add64(x376, x399, uint64(p384Uint1(x411)))
+	var x414 uint64
+	_, x414 = bits.Mul64(x400, 0x100000001)
+	var x416 uint64
+	var x417 uint64
+	x417, x416 = bits.Mul64(x414, 0xffffffffffffffff)
+	var x418 uint64
+	var x419 uint64
+	x419, x418 = bits.Mul64(x414, 0xffffffffffffffff)
+	var x420 uint64
+	var x421 uint64
+	x421, x420 = bits.Mul64(x414, 0xffffffffffffffff)
+	var x422 uint64
+	var x423 uint64
+	x423, x422 = bits.Mul64(x414, 0xfffffffffffffffe)
+	var x424 uint64
+	var x425 uint64
+	x425, x424 = bits.Mul64(x414, 0xffffffff00000000)
+	var x426 uint64
+	var x427 uint64
+	x427, x426 = bits.Mul64(x414, 0xffffffff)
+	var x428 uint64
+	var x429 uint64
+	x428, x429 = bits.Add64(x427, x424, uint64(0x0))
+	var x430 uint64
+	var x431 uint64
+	x430, x431 = bits.Add64(x425, x422, uint64(p384Uint1(x429)))
+	var x432 uint64
+	var x433 uint64
+	x432, x433 = bits.Add64(x423, x420, uint64(p384Uint1(x431)))
+	var x434 uint64
+	var x435 uint64
+	x434, x435 = bits.Add64(x421, x418, uint64(p384Uint1(x433)))
+	var x436 uint64
+	var x437 uint64
+	x436, x437 = bits.Add64(x419, x416, uint64(p384Uint1(x435)))
+	x438 := (uint64(p384Uint1(x437)) + x417)
+	var x440 uint64
+	_, x440 = bits.Add64(x400, x426, uint64(0x0))
+	var x441 uint64
+	var x442 uint64
+	x441, x442 = bits.Add64(x402, x428, uint64(p384Uint1(x440)))
+	var x443 uint64
+	var x444 uint64
+	x443, x444 = bits.Add64(x404, x430, uint64(p384Uint1(x442)))
+	var x445 uint64
+	var x446 uint64
+	x445, x446 = bits.Add64(x406, x432, uint64(p384Uint1(x444)))
+	var x447 uint64
+	var x448 uint64
+	x447, x448 = bits.Add64(x408, x434, uint64(p384Uint1(x446)))
+	var x449 uint64
+	var x450 uint64
+	x449, x450 = bits.Add64(x410, x436, uint64(p384Uint1(x448)))
+	var x451 uint64
+	var x452 uint64
+	x451, x452 = bits.Add64(x412, x438, uint64(p384Uint1(x450)))
+	x453 := (uint64(p384Uint1(x452)) + uint64(p384Uint1(x413)))
+	var x454 uint64
+	var x455 uint64
+	x454, x455 = bits.Sub64(x441, 0xffffffff, uint64(0x0))
+	var x456 uint64
+	var x457 uint64
+	x456, x457 = bits.Sub64(x443, 0xffffffff00000000, uint64(p384Uint1(x455)))
+	var x458 uint64
+	var x459 uint64
+	x458, x459 = bits.Sub64(x445, 0xfffffffffffffffe, uint64(p384Uint1(x457)))
+	var x460 uint64
+	var x461 uint64
+	x460, x461 = bits.Sub64(x447, 0xffffffffffffffff, uint64(p384Uint1(x459)))
+	var x462 uint64
+	var x463 uint64
+	x462, x463 = bits.Sub64(x449, 0xffffffffffffffff, uint64(p384Uint1(x461)))
+	var x464 uint64
+	var x465 uint64
+	x464, x465 = bits.Sub64(x451, 0xffffffffffffffff, uint64(p384Uint1(x463)))
+	var x467 uint64
+	_, x467 = bits.Sub64(x453, uint64(0x0), uint64(p384Uint1(x465)))
+	var x468 uint64
+	p384CmovznzU64(&x468, p384Uint1(x467), x454, x441)
+	var x469 uint64
+	p384CmovznzU64(&x469, p384Uint1(x467), x456, x443)
+	var x470 uint64
+	p384CmovznzU64(&x470, p384Uint1(x467), x458, x445)
+	var x471 uint64
+	p384CmovznzU64(&x471, p384Uint1(x467), x460, x447)
+	var x472 uint64
+	p384CmovznzU64(&x472, p384Uint1(x467), x462, x449)
+	var x473 uint64
+	p384CmovznzU64(&x473, p384Uint1(x467), x464, x451)
+	out1[0] = x468
+	out1[1] = x469
+	out1[2] = x470
+	out1[3] = x471
+	out1[4] = x472
+	out1[5] = x473
+}
+
+// p384Add adds two field elements in the Montgomery domain.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//	0 ≤ eval arg2 < m
+//
+// Postconditions:
+//
+//	eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) + eval (from_montgomery arg2)) mod m
+//	0 ≤ eval out1 < m
+func p384Add(out1 *p384MontgomeryDomainFieldElement, arg1 *p384MontgomeryDomainFieldElement, arg2 *p384MontgomeryDomainFieldElement) {
+	var x1 uint64
+	var x2 uint64
+	x1, x2 = bits.Add64(arg1[0], arg2[0], uint64(0x0))
+	var x3 uint64
+	var x4 uint64
+	x3, x4 = bits.Add64(arg1[1], arg2[1], uint64(p384Uint1(x2)))
+	var x5 uint64
+	var x6 uint64
+	x5, x6 = bits.Add64(arg1[2], arg2[2], uint64(p384Uint1(x4)))
+	var x7 uint64
+	var x8 uint64
+	x7, x8 = bits.Add64(arg1[3], arg2[3], uint64(p384Uint1(x6)))
+	var x9 uint64
+	var x10 uint64
+	x9, x10 = bits.Add64(arg1[4], arg2[4], uint64(p384Uint1(x8)))
+	var x11 uint64
+	var x12 uint64
+	x11, x12 = bits.Add64(arg1[5], arg2[5], uint64(p384Uint1(x10)))
+	var x13 uint64
+	var x14 uint64
+	x13, x14 = bits.Sub64(x1, 0xffffffff, uint64(0x0))
+	var x15 uint64
+	var x16 uint64
+	x15, x16 = bits.Sub64(x3, 0xffffffff00000000, uint64(p384Uint1(x14)))
+	var x17 uint64
+	var x18 uint64
+	x17, x18 = bits.Sub64(x5, 0xfffffffffffffffe, uint64(p384Uint1(x16)))
+	var x19 uint64
+	var x20 uint64
+	x19, x20 = bits.Sub64(x7, 0xffffffffffffffff, uint64(p384Uint1(x18)))
+	var x21 uint64
+	var x22 uint64
+	x21, x22 = bits.Sub64(x9, 0xffffffffffffffff, uint64(p384Uint1(x20)))
+	var x23 uint64
+	var x24 uint64
+	x23, x24 = bits.Sub64(x11, 0xffffffffffffffff, uint64(p384Uint1(x22)))
+	var x26 uint64
+	_, x26 = bits.Sub64(uint64(p384Uint1(x12)), uint64(0x0), uint64(p384Uint1(x24)))
+	var x27 uint64
+	p384CmovznzU64(&x27, p384Uint1(x26), x13, x1)
+	var x28 uint64
+	p384CmovznzU64(&x28, p384Uint1(x26), x15, x3)
+	var x29 uint64
+	p384CmovznzU64(&x29, p384Uint1(x26), x17, x5)
+	var x30 uint64
+	p384CmovznzU64(&x30, p384Uint1(x26), x19, x7)
+	var x31 uint64
+	p384CmovznzU64(&x31, p384Uint1(x26), x21, x9)
+	var x32 uint64
+	p384CmovznzU64(&x32, p384Uint1(x26), x23, x11)
+	out1[0] = x27
+	out1[1] = x28
+	out1[2] = x29
+	out1[3] = x30
+	out1[4] = x31
+	out1[5] = x32
+}
+
+// p384Sub subtracts two field elements in the Montgomery domain.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//	0 ≤ eval arg2 < m
+//
+// Postconditions:
+//
+//	eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) - eval (from_montgomery arg2)) mod m
+//	0 ≤ eval out1 < m
+func p384Sub(out1 *p384MontgomeryDomainFieldElement, arg1 *p384MontgomeryDomainFieldElement, arg2 *p384MontgomeryDomainFieldElement) {
+	var x1 uint64
+	var x2 uint64
+	x1, x2 = bits.Sub64(arg1[0], arg2[0], uint64(0x0))
+	var x3 uint64
+	var x4 uint64
+	x3, x4 = bits.Sub64(arg1[1], arg2[1], uint64(p384Uint1(x2)))
+	var x5 uint64
+	var x6 uint64
+	x5, x6 = bits.Sub64(arg1[2], arg2[2], uint64(p384Uint1(x4)))
+	var x7 uint64
+	var x8 uint64
+	x7, x8 = bits.Sub64(arg1[3], arg2[3], uint64(p384Uint1(x6)))
+	var x9 uint64
+	var x10 uint64
+	x9, x10 = bits.Sub64(arg1[4], arg2[4], uint64(p384Uint1(x8)))
+	var x11 uint64
+	var x12 uint64
+	x11, x12 = bits.Sub64(arg1[5], arg2[5], uint64(p384Uint1(x10)))
+	var x13 uint64
+	p384CmovznzU64(&x13, p384Uint1(x12), uint64(0x0), 0xffffffffffffffff)
+	var x14 uint64
+	var x15 uint64
+	x14, x15 = bits.Add64(x1, (x13 & 0xffffffff), uint64(0x0))
+	var x16 uint64
+	var x17 uint64
+	x16, x17 = bits.Add64(x3, (x13 & 0xffffffff00000000), uint64(p384Uint1(x15)))
+	var x18 uint64
+	var x19 uint64
+	x18, x19 = bits.Add64(x5, (x13 & 0xfffffffffffffffe), uint64(p384Uint1(x17)))
+	var x20 uint64
+	var x21 uint64
+	x20, x21 = bits.Add64(x7, x13, uint64(p384Uint1(x19)))
+	var x22 uint64
+	var x23 uint64
+	x22, x23 = bits.Add64(x9, x13, uint64(p384Uint1(x21)))
+	var x24 uint64
+	x24, _ = bits.Add64(x11, x13, uint64(p384Uint1(x23)))
+	out1[0] = x14
+	out1[1] = x16
+	out1[2] = x18
+	out1[3] = x20
+	out1[4] = x22
+	out1[5] = x24
+}
+
+// p384SetOne returns the field element one in the Montgomery domain.
+//
+// Postconditions:
+//
+//	eval (from_montgomery out1) mod m = 1 mod m
+//	0 ≤ eval out1 < m
+func p384SetOne(out1 *p384MontgomeryDomainFieldElement) {
+	out1[0] = 0xffffffff00000001
+	out1[1] = 0xffffffff
+	out1[2] = uint64(0x1)
+	out1[3] = uint64(0x0)
+	out1[4] = uint64(0x0)
+	out1[5] = uint64(0x0)
+}
+
+// p384FromMontgomery translates a field element out of the Montgomery domain.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//
+// Postconditions:
+//
+//	eval out1 mod m = (eval arg1 * ((2^64)⁻¹ mod m)^6) mod m
+//	0 ≤ eval out1 < m
+func p384FromMontgomery(out1 *p384NonMontgomeryDomainFieldElement, arg1 *p384MontgomeryDomainFieldElement) {
+	x1 := arg1[0]
+	var x2 uint64
+	_, x2 = bits.Mul64(x1, 0x100000001)
+	var x4 uint64
+	var x5 uint64
+	x5, x4 = bits.Mul64(x2, 0xffffffffffffffff)
+	var x6 uint64
+	var x7 uint64
+	x7, x6 = bits.Mul64(x2, 0xffffffffffffffff)
+	var x8 uint64
+	var x9 uint64
+	x9, x8 = bits.Mul64(x2, 0xffffffffffffffff)
+	var x10 uint64
+	var x11 uint64
+	x11, x10 = bits.Mul64(x2, 0xfffffffffffffffe)
+	var x12 uint64
+	var x13 uint64
+	x13, x12 = bits.Mul64(x2, 0xffffffff00000000)
+	var x14 uint64
+	var x15 uint64
+	x15, x14 = bits.Mul64(x2, 0xffffffff)
+	var x16 uint64
+	var x17 uint64
+	x16, x17 = bits.Add64(x15, x12, uint64(0x0))
+	var x18 uint64
+	var x19 uint64
+	x18, x19 = bits.Add64(x13, x10, uint64(p384Uint1(x17)))
+	var x20 uint64
+	var x21 uint64
+	x20, x21 = bits.Add64(x11, x8, uint64(p384Uint1(x19)))
+	var x22 uint64
+	var x23 uint64
+	x22, x23 = bits.Add64(x9, x6, uint64(p384Uint1(x21)))
+	var x24 uint64
+	var x25 uint64
+	x24, x25 = bits.Add64(x7, x4, uint64(p384Uint1(x23)))
+	var x27 uint64
+	_, x27 = bits.Add64(x1, x14, uint64(0x0))
+	var x28 uint64
+	var x29 uint64
+	x28, x29 = bits.Add64(uint64(0x0), x16, uint64(p384Uint1(x27)))
+	var x30 uint64
+	var x31 uint64
+	x30, x31 = bits.Add64(uint64(0x0), x18, uint64(p384Uint1(x29)))
+	var x32 uint64
+	var x33 uint64
+	x32, x33 = bits.Add64(uint64(0x0), x20, uint64(p384Uint1(x31)))
+	var x34 uint64
+	var x35 uint64
+	x34, x35 = bits.Add64(uint64(0x0), x22, uint64(p384Uint1(x33)))
+	var x36 uint64
+	var x37 uint64
+	x36, x37 = bits.Add64(uint64(0x0), x24, uint64(p384Uint1(x35)))
+	var x38 uint64
+	var x39 uint64
+	x38, x39 = bits.Add64(uint64(0x0), (uint64(p384Uint1(x25)) + x5), uint64(p384Uint1(x37)))
+	var x40 uint64
+	var x41 uint64
+	x40, x41 = bits.Add64(x28, arg1[1], uint64(0x0))
+	var x42 uint64
+	var x43 uint64
+	x42, x43 = bits.Add64(x30, uint64(0x0), uint64(p384Uint1(x41)))
+	var x44 uint64
+	var x45 uint64
+	x44, x45 = bits.Add64(x32, uint64(0x0), uint64(p384Uint1(x43)))
+	var x46 uint64
+	var x47 uint64
+	x46, x47 = bits.Add64(x34, uint64(0x0), uint64(p384Uint1(x45)))
+	var x48 uint64
+	var x49 uint64
+	x48, x49 = bits.Add64(x36, uint64(0x0), uint64(p384Uint1(x47)))
+	var x50 uint64
+	var x51 uint64
+	x50, x51 = bits.Add64(x38, uint64(0x0), uint64(p384Uint1(x49)))
+	var x52 uint64
+	_, x52 = bits.Mul64(x40, 0x100000001)
+	var x54 uint64
+	var x55 uint64
+	x55, x54 = bits.Mul64(x52, 0xffffffffffffffff)
+	var x56 uint64
+	var x57 uint64
+	x57, x56 = bits.Mul64(x52, 0xffffffffffffffff)
+	var x58 uint64
+	var x59 uint64
+	x59, x58 = bits.Mul64(x52, 0xffffffffffffffff)
+	var x60 uint64
+	var x61 uint64
+	x61, x60 = bits.Mul64(x52, 0xfffffffffffffffe)
+	var x62 uint64
+	var x63 uint64
+	x63, x62 = bits.Mul64(x52, 0xffffffff00000000)
+	var x64 uint64
+	var x65 uint64
+	x65, x64 = bits.Mul64(x52, 0xffffffff)
+	var x66 uint64
+	var x67 uint64
+	x66, x67 = bits.Add64(x65, x62, uint64(0x0))
+	var x68 uint64
+	var x69 uint64
+	x68, x69 = bits.Add64(x63, x60, uint64(p384Uint1(x67)))
+	var x70 uint64
+	var x71 uint64
+	x70, x71 = bits.Add64(x61, x58, uint64(p384Uint1(x69)))
+	var x72 uint64
+	var x73 uint64
+	x72, x73 = bits.Add64(x59, x56, uint64(p384Uint1(x71)))
+	var x74 uint64
+	var x75 uint64
+	x74, x75 = bits.Add64(x57, x54, uint64(p384Uint1(x73)))
+	var x77 uint64
+	_, x77 = bits.Add64(x40, x64, uint64(0x0))
+	var x78 uint64
+	var x79 uint64
+	x78, x79 = bits.Add64(x42, x66, uint64(p384Uint1(x77)))
+	var x80 uint64
+	var x81 uint64
+	x80, x81 = bits.Add64(x44, x68, uint64(p384Uint1(x79)))
+	var x82 uint64
+	var x83 uint64
+	x82, x83 = bits.Add64(x46, x70, uint64(p384Uint1(x81)))
+	var x84 uint64
+	var x85 uint64
+	x84, x85 = bits.Add64(x48, x72, uint64(p384Uint1(x83)))
+	var x86 uint64
+	var x87 uint64
+	x86, x87 = bits.Add64(x50, x74, uint64(p384Uint1(x85)))
+	var x88 uint64
+	var x89 uint64
+	x88, x89 = bits.Add64((uint64(p384Uint1(x51)) + uint64(p384Uint1(x39))), (uint64(p384Uint1(x75)) + x55), uint64(p384Uint1(x87)))
+	var x90 uint64
+	var x91 uint64
+	x90, x91 = bits.Add64(x78, arg1[2], uint64(0x0))
+	var x92 uint64
+	var x93 uint64
+	x92, x93 = bits.Add64(x80, uint64(0x0), uint64(p384Uint1(x91)))
+	var x94 uint64
+	var x95 uint64
+	x94, x95 = bits.Add64(x82, uint64(0x0), uint64(p384Uint1(x93)))
+	var x96 uint64
+	var x97 uint64
+	x96, x97 = bits.Add64(x84, uint64(0x0), uint64(p384Uint1(x95)))
+	var x98 uint64
+	var x99 uint64
+	x98, x99 = bits.Add64(x86, uint64(0x0), uint64(p384Uint1(x97)))
+	var x100 uint64
+	var x101 uint64
+	x100, x101 = bits.Add64(x88, uint64(0x0), uint64(p384Uint1(x99)))
+	var x102 uint64
+	_, x102 = bits.Mul64(x90, 0x100000001)
+	var x104 uint64
+	var x105 uint64
+	x105, x104 = bits.Mul64(x102, 0xffffffffffffffff)
+	var x106 uint64
+	var x107 uint64
+	x107, x106 = bits.Mul64(x102, 0xffffffffffffffff)
+	var x108 uint64
+	var x109 uint64
+	x109, x108 = bits.Mul64(x102, 0xffffffffffffffff)
+	var x110 uint64
+	var x111 uint64
+	x111, x110 = bits.Mul64(x102, 0xfffffffffffffffe)
+	var x112 uint64
+	var x113 uint64
+	x113, x112 = bits.Mul64(x102, 0xffffffff00000000)
+	var x114 uint64
+	var x115 uint64
+	x115, x114 = bits.Mul64(x102, 0xffffffff)
+	var x116 uint64
+	var x117 uint64
+	x116, x117 = bits.Add64(x115, x112, uint64(0x0))
+	var x118 uint64
+	var x119 uint64
+	x118, x119 = bits.Add64(x113, x110, uint64(p384Uint1(x117)))
+	var x120 uint64
+	var x121 uint64
+	x120, x121 = bits.Add64(x111, x108, uint64(p384Uint1(x119)))
+	var x122 uint64
+	var x123 uint64
+	x122, x123 = bits.Add64(x109, x106, uint64(p384Uint1(x121)))
+	var x124 uint64
+	var x125 uint64
+	x124, x125 = bits.Add64(x107, x104, uint64(p384Uint1(x123)))
+	var x127 uint64
+	_, x127 = bits.Add64(x90, x114, uint64(0x0))
+	var x128 uint64
+	var x129 uint64
+	x128, x129 = bits.Add64(x92, x116, uint64(p384Uint1(x127)))
+	var x130 uint64
+	var x131 uint64
+	x130, x131 = bits.Add64(x94, x118, uint64(p384Uint1(x129)))
+	var x132 uint64
+	var x133 uint64
+	x132, x133 = bits.Add64(x96, x120, uint64(p384Uint1(x131)))
+	var x134 uint64
+	var x135 uint64
+	x134, x135 = bits.Add64(x98, x122, uint64(p384Uint1(x133)))
+	var x136 uint64
+	var x137 uint64
+	x136, x137 = bits.Add64(x100, x124, uint64(p384Uint1(x135)))
+	var x138 uint64
+	var x139 uint64
+	x138, x139 = bits.Add64((uint64(p384Uint1(x101)) + uint64(p384Uint1(x89))), (uint64(p384Uint1(x125)) + x105), uint64(p384Uint1(x137)))
+	var x140 uint64
+	var x141 uint64
+	x140, x141 = bits.Add64(x128, arg1[3], uint64(0x0))
+	var x142 uint64
+	var x143 uint64
+	x142, x143 = bits.Add64(x130, uint64(0x0), uint64(p384Uint1(x141)))
+	var x144 uint64
+	var x145 uint64
+	x144, x145 = bits.Add64(x132, uint64(0x0), uint64(p384Uint1(x143)))
+	var x146 uint64
+	var x147 uint64
+	x146, x147 = bits.Add64(x134, uint64(0x0), uint64(p384Uint1(x145)))
+	var x148 uint64
+	var x149 uint64
+	x148, x149 = bits.Add64(x136, uint64(0x0), uint64(p384Uint1(x147)))
+	var x150 uint64
+	var x151 uint64
+	x150, x151 = bits.Add64(x138, uint64(0x0), uint64(p384Uint1(x149)))
+	var x152 uint64
+	_, x152 = bits.Mul64(x140, 0x100000001)
+	var x154 uint64
+	var x155 uint64
+	x155, x154 = bits.Mul64(x152, 0xffffffffffffffff)
+	var x156 uint64
+	var x157 uint64
+	x157, x156 = bits.Mul64(x152, 0xffffffffffffffff)
+	var x158 uint64
+	var x159 uint64
+	x159, x158 = bits.Mul64(x152, 0xffffffffffffffff)
+	var x160 uint64
+	var x161 uint64
+	x161, x160 = bits.Mul64(x152, 0xfffffffffffffffe)
+	var x162 uint64
+	var x163 uint64
+	x163, x162 = bits.Mul64(x152, 0xffffffff00000000)
+	var x164 uint64
+	var x165 uint64
+	x165, x164 = bits.Mul64(x152, 0xffffffff)
+	var x166 uint64
+	var x167 uint64
+	x166, x167 = bits.Add64(x165, x162, uint64(0x0))
+	var x168 uint64
+	var x169 uint64
+	x168, x169 = bits.Add64(x163, x160, uint64(p384Uint1(x167)))
+	var x170 uint64
+	var x171 uint64
+	x170, x171 = bits.Add64(x161, x158, uint64(p384Uint1(x169)))
+	var x172 uint64
+	var x173 uint64
+	x172, x173 = bits.Add64(x159, x156, uint64(p384Uint1(x171)))
+	var x174 uint64
+	var x175 uint64
+	x174, x175 = bits.Add64(x157, x154, uint64(p384Uint1(x173)))
+	var x177 uint64
+	_, x177 = bits.Add64(x140, x164, uint64(0x0))
+	var x178 uint64
+	var x179 uint64
+	x178, x179 = bits.Add64(x142, x166, uint64(p384Uint1(x177)))
+	var x180 uint64
+	var x181 uint64
+	x180, x181 = bits.Add64(x144, x168, uint64(p384Uint1(x179)))
+	var x182 uint64
+	var x183 uint64
+	x182, x183 = bits.Add64(x146, x170, uint64(p384Uint1(x181)))
+	var x184 uint64
+	var x185 uint64
+	x184, x185 = bits.Add64(x148, x172, uint64(p384Uint1(x183)))
+	var x186 uint64
+	var x187 uint64
+	x186, x187 = bits.Add64(x150, x174, uint64(p384Uint1(x185)))
+	var x188 uint64
+	var x189 uint64
+	x188, x189 = bits.Add64((uint64(p384Uint1(x151)) + uint64(p384Uint1(x139))), (uint64(p384Uint1(x175)) + x155), uint64(p384Uint1(x187)))
+	var x190 uint64
+	var x191 uint64
+	x190, x191 = bits.Add64(x178, arg1[4], uint64(0x0))
+	var x192 uint64
+	var x193 uint64
+	x192, x193 = bits.Add64(x180, uint64(0x0), uint64(p384Uint1(x191)))
+	var x194 uint64
+	var x195 uint64
+	x194, x195 = bits.Add64(x182, uint64(0x0), uint64(p384Uint1(x193)))
+	var x196 uint64
+	var x197 uint64
+	x196, x197 = bits.Add64(x184, uint64(0x0), uint64(p384Uint1(x195)))
+	var x198 uint64
+	var x199 uint64
+	x198, x199 = bits.Add64(x186, uint64(0x0), uint64(p384Uint1(x197)))
+	var x200 uint64
+	var x201 uint64
+	x200, x201 = bits.Add64(x188, uint64(0x0), uint64(p384Uint1(x199)))
+	var x202 uint64
+	_, x202 = bits.Mul64(x190, 0x100000001)
+	var x204 uint64
+	var x205 uint64
+	x205, x204 = bits.Mul64(x202, 0xffffffffffffffff)
+	var x206 uint64
+	var x207 uint64
+	x207, x206 = bits.Mul64(x202, 0xffffffffffffffff)
+	var x208 uint64
+	var x209 uint64
+	x209, x208 = bits.Mul64(x202, 0xffffffffffffffff)
+	var x210 uint64
+	var x211 uint64
+	x211, x210 = bits.Mul64(x202, 0xfffffffffffffffe)
+	var x212 uint64
+	var x213 uint64
+	x213, x212 = bits.Mul64(x202, 0xffffffff00000000)
+	var x214 uint64
+	var x215 uint64
+	x215, x214 = bits.Mul64(x202, 0xffffffff)
+	var x216 uint64
+	var x217 uint64
+	x216, x217 = bits.Add64(x215, x212, uint64(0x0))
+	var x218 uint64
+	var x219 uint64
+	x218, x219 = bits.Add64(x213, x210, uint64(p384Uint1(x217)))
+	var x220 uint64
+	var x221 uint64
+	x220, x221 = bits.Add64(x211, x208, uint64(p384Uint1(x219)))
+	var x222 uint64
+	var x223 uint64
+	x222, x223 = bits.Add64(x209, x206, uint64(p384Uint1(x221)))
+	var x224 uint64
+	var x225 uint64
+	x224, x225 = bits.Add64(x207, x204, uint64(p384Uint1(x223)))
+	var x227 uint64
+	_, x227 = bits.Add64(x190, x214, uint64(0x0))
+	var x228 uint64
+	var x229 uint64
+	x228, x229 = bits.Add64(x192, x216, uint64(p384Uint1(x227)))
+	var x230 uint64
+	var x231 uint64
+	x230, x231 = bits.Add64(x194, x218, uint64(p384Uint1(x229)))
+	var x232 uint64
+	var x233 uint64
+	x232, x233 = bits.Add64(x196, x220, uint64(p384Uint1(x231)))
+	var x234 uint64
+	var x235 uint64
+	x234, x235 = bits.Add64(x198, x222, uint64(p384Uint1(x233)))
+	var x236 uint64
+	var x237 uint64
+	x236, x237 = bits.Add64(x200, x224, uint64(p384Uint1(x235)))
+	var x238 uint64
+	var x239 uint64
+	x238, x239 = bits.Add64((uint64(p384Uint1(x201)) + uint64(p384Uint1(x189))), (uint64(p384Uint1(x225)) + x205), uint64(p384Uint1(x237)))
+	var x240 uint64
+	var x241 uint64
+	x240, x241 = bits.Add64(x228, arg1[5], uint64(0x0))
+	var x242 uint64
+	var x243 uint64
+	x242, x243 = bits.Add64(x230, uint64(0x0), uint64(p384Uint1(x241)))
+	var x244 uint64
+	var x245 uint64
+	x244, x245 = bits.Add64(x232, uint64(0x0), uint64(p384Uint1(x243)))
+	var x246 uint64
+	var x247 uint64
+	x246, x247 = bits.Add64(x234, uint64(0x0), uint64(p384Uint1(x245)))
+	var x248 uint64
+	var x249 uint64
+	x248, x249 = bits.Add64(x236, uint64(0x0), uint64(p384Uint1(x247)))
+	var x250 uint64
+	var x251 uint64
+	x250, x251 = bits.Add64(x238, uint64(0x0), uint64(p384Uint1(x249)))
+	var x252 uint64
+	_, x252 = bits.Mul64(x240, 0x100000001)
+	var x254 uint64
+	var x255 uint64
+	x255, x254 = bits.Mul64(x252, 0xffffffffffffffff)
+	var x256 uint64
+	var x257 uint64
+	x257, x256 = bits.Mul64(x252, 0xffffffffffffffff)
+	var x258 uint64
+	var x259 uint64
+	x259, x258 = bits.Mul64(x252, 0xffffffffffffffff)
+	var x260 uint64
+	var x261 uint64
+	x261, x260 = bits.Mul64(x252, 0xfffffffffffffffe)
+	var x262 uint64
+	var x263 uint64
+	x263, x262 = bits.Mul64(x252, 0xffffffff00000000)
+	var x264 uint64
+	var x265 uint64
+	x265, x264 = bits.Mul64(x252, 0xffffffff)
+	var x266 uint64
+	var x267 uint64
+	x266, x267 = bits.Add64(x265, x262, uint64(0x0))
+	var x268 uint64
+	var x269 uint64
+	x268, x269 = bits.Add64(x263, x260, uint64(p384Uint1(x267)))
+	var x270 uint64
+	var x271 uint64
+	x270, x271 = bits.Add64(x261, x258, uint64(p384Uint1(x269)))
+	var x272 uint64
+	var x273 uint64
+	x272, x273 = bits.Add64(x259, x256, uint64(p384Uint1(x271)))
+	var x274 uint64
+	var x275 uint64
+	x274, x275 = bits.Add64(x257, x254, uint64(p384Uint1(x273)))
+	var x277 uint64
+	_, x277 = bits.Add64(x240, x264, uint64(0x0))
+	var x278 uint64
+	var x279 uint64
+	x278, x279 = bits.Add64(x242, x266, uint64(p384Uint1(x277)))
+	var x280 uint64
+	var x281 uint64
+	x280, x281 = bits.Add64(x244, x268, uint64(p384Uint1(x279)))
+	var x282 uint64
+	var x283 uint64
+	x282, x283 = bits.Add64(x246, x270, uint64(p384Uint1(x281)))
+	var x284 uint64
+	var x285 uint64
+	x284, x285 = bits.Add64(x248, x272, uint64(p384Uint1(x283)))
+	var x286 uint64
+	var x287 uint64
+	x286, x287 = bits.Add64(x250, x274, uint64(p384Uint1(x285)))
+	var x288 uint64
+	var x289 uint64
+	x288, x289 = bits.Add64((uint64(p384Uint1(x251)) + uint64(p384Uint1(x239))), (uint64(p384Uint1(x275)) + x255), uint64(p384Uint1(x287)))
+	var x290 uint64
+	var x291 uint64
+	x290, x291 = bits.Sub64(x278, 0xffffffff, uint64(0x0))
+	var x292 uint64
+	var x293 uint64
+	x292, x293 = bits.Sub64(x280, 0xffffffff00000000, uint64(p384Uint1(x291)))
+	var x294 uint64
+	var x295 uint64
+	x294, x295 = bits.Sub64(x282, 0xfffffffffffffffe, uint64(p384Uint1(x293)))
+	var x296 uint64
+	var x297 uint64
+	x296, x297 = bits.Sub64(x284, 0xffffffffffffffff, uint64(p384Uint1(x295)))
+	var x298 uint64
+	var x299 uint64
+	x298, x299 = bits.Sub64(x286, 0xffffffffffffffff, uint64(p384Uint1(x297)))
+	var x300 uint64
+	var x301 uint64
+	x300, x301 = bits.Sub64(x288, 0xffffffffffffffff, uint64(p384Uint1(x299)))
+	var x303 uint64
+	_, x303 = bits.Sub64(uint64(p384Uint1(x289)), uint64(0x0), uint64(p384Uint1(x301)))
+	var x304 uint64
+	p384CmovznzU64(&x304, p384Uint1(x303), x290, x278)
+	var x305 uint64
+	p384CmovznzU64(&x305, p384Uint1(x303), x292, x280)
+	var x306 uint64
+	p384CmovznzU64(&x306, p384Uint1(x303), x294, x282)
+	var x307 uint64
+	p384CmovznzU64(&x307, p384Uint1(x303), x296, x284)
+	var x308 uint64
+	p384CmovznzU64(&x308, p384Uint1(x303), x298, x286)
+	var x309 uint64
+	p384CmovznzU64(&x309, p384Uint1(x303), x300, x288)
+	out1[0] = x304
+	out1[1] = x305
+	out1[2] = x306
+	out1[3] = x307
+	out1[4] = x308
+	out1[5] = x309
+}
+
+// p384ToMontgomery translates a field element into the Montgomery domain.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//
+// Postconditions:
+//
+//	eval (from_montgomery out1) mod m = eval arg1 mod m
+//	0 ≤ eval out1 < m
+func p384ToMontgomery(out1 *p384MontgomeryDomainFieldElement, arg1 *p384NonMontgomeryDomainFieldElement) {
+	x1 := arg1[1]
+	x2 := arg1[2]
+	x3 := arg1[3]
+	x4 := arg1[4]
+	x5 := arg1[5]
+	x6 := arg1[0]
+	var x7 uint64
+	var x8 uint64
+	x8, x7 = bits.Mul64(x6, 0x200000000)
+	var x9 uint64
+	var x10 uint64
+	x10, x9 = bits.Mul64(x6, 0xfffffffe00000000)
+	var x11 uint64
+	var x12 uint64
+	x12, x11 = bits.Mul64(x6, 0x200000000)
+	var x13 uint64
+	var x14 uint64
+	x14, x13 = bits.Mul64(x6, 0xfffffffe00000001)
+	var x15 uint64
+	var x16 uint64
+	x15, x16 = bits.Add64(x14, x11, uint64(0x0))
+	var x17 uint64
+	var x18 uint64
+	x17, x18 = bits.Add64(x12, x9, uint64(p384Uint1(x16)))
+	var x19 uint64
+	var x20 uint64
+	x19, x20 = bits.Add64(x10, x7, uint64(p384Uint1(x18)))
+	var x21 uint64
+	var x22 uint64
+	x21, x22 = bits.Add64(x8, x6, uint64(p384Uint1(x20)))
+	var x23 uint64
+	_, x23 = bits.Mul64(x13, 0x100000001)
+	var x25 uint64
+	var x26 uint64
+	x26, x25 = bits.Mul64(x23, 0xffffffffffffffff)
+	var x27 uint64
+	var x28 uint64
+	x28, x27 = bits.Mul64(x23, 0xffffffffffffffff)
+	var x29 uint64
+	var x30 uint64
+	x30, x29 = bits.Mul64(x23, 0xffffffffffffffff)
+	var x31 uint64
+	var x32 uint64
+	x32, x31 = bits.Mul64(x23, 0xfffffffffffffffe)
+	var x33 uint64
+	var x34 uint64
+	x34, x33 = bits.Mul64(x23, 0xffffffff00000000)
+	var x35 uint64
+	var x36 uint64
+	x36, x35 = bits.Mul64(x23, 0xffffffff)
+	var x37 uint64
+	var x38 uint64
+	x37, x38 = bits.Add64(x36, x33, uint64(0x0))
+	var x39 uint64
+	var x40 uint64
+	x39, x40 = bits.Add64(x34, x31, uint64(p384Uint1(x38)))
+	var x41 uint64
+	var x42 uint64
+	x41, x42 = bits.Add64(x32, x29, uint64(p384Uint1(x40)))
+	var x43 uint64
+	var x44 uint64
+	x43, x44 = bits.Add64(x30, x27, uint64(p384Uint1(x42)))
+	var x45 uint64
+	var x46 uint64
+	x45, x46 = bits.Add64(x28, x25, uint64(p384Uint1(x44)))
+	var x48 uint64
+	_, x48 = bits.Add64(x13, x35, uint64(0x0))
+	var x49 uint64
+	var x50 uint64
+	x49, x50 = bits.Add64(x15, x37, uint64(p384Uint1(x48)))
+	var x51 uint64
+	var x52 uint64
+	x51, x52 = bits.Add64(x17, x39, uint64(p384Uint1(x50)))
+	var x53 uint64
+	var x54 uint64
+	x53, x54 = bits.Add64(x19, x41, uint64(p384Uint1(x52)))
+	var x55 uint64
+	var x56 uint64
+	x55, x56 = bits.Add64(x21, x43, uint64(p384Uint1(x54)))
+	var x57 uint64
+	var x58 uint64
+	x57, x58 = bits.Add64(uint64(p384Uint1(x22)), x45, uint64(p384Uint1(x56)))
+	var x59 uint64
+	var x60 uint64
+	x59, x60 = bits.Add64(uint64(0x0), (uint64(p384Uint1(x46)) + x26), uint64(p384Uint1(x58)))
+	var x61 uint64
+	var x62 uint64
+	x62, x61 = bits.Mul64(x1, 0x200000000)
+	var x63 uint64
+	var x64 uint64
+	x64, x63 = bits.Mul64(x1, 0xfffffffe00000000)
+	var x65 uint64
+	var x66 uint64
+	x66, x65 = bits.Mul64(x1, 0x200000000)
+	var x67 uint64
+	var x68 uint64
+	x68, x67 = bits.Mul64(x1, 0xfffffffe00000001)
+	var x69 uint64
+	var x70 uint64
+	x69, x70 = bits.Add64(x68, x65, uint64(0x0))
+	var x71 uint64
+	var x72 uint64
+	x71, x72 = bits.Add64(x66, x63, uint64(p384Uint1(x70)))
+	var x73 uint64
+	var x74 uint64
+	x73, x74 = bits.Add64(x64, x61, uint64(p384Uint1(x72)))
+	var x75 uint64
+	var x76 uint64
+	x75, x76 = bits.Add64(x62, x1, uint64(p384Uint1(x74)))
+	var x77 uint64
+	var x78 uint64
+	x77, x78 = bits.Add64(x49, x67, uint64(0x0))
+	var x79 uint64
+	var x80 uint64
+	x79, x80 = bits.Add64(x51, x69, uint64(p384Uint1(x78)))
+	var x81 uint64
+	var x82 uint64
+	x81, x82 = bits.Add64(x53, x71, uint64(p384Uint1(x80)))
+	var x83 uint64
+	var x84 uint64
+	x83, x84 = bits.Add64(x55, x73, uint64(p384Uint1(x82)))
+	var x85 uint64
+	var x86 uint64
+	x85, x86 = bits.Add64(x57, x75, uint64(p384Uint1(x84)))
+	var x87 uint64
+	var x88 uint64
+	x87, x88 = bits.Add64(x59, uint64(p384Uint1(x76)), uint64(p384Uint1(x86)))
+	var x89 uint64
+	_, x89 = bits.Mul64(x77, 0x100000001)
+	var x91 uint64
+	var x92 uint64
+	x92, x91 = bits.Mul64(x89, 0xffffffffffffffff)
+	var x93 uint64
+	var x94 uint64
+	x94, x93 = bits.Mul64(x89, 0xffffffffffffffff)
+	var x95 uint64
+	var x96 uint64
+	x96, x95 = bits.Mul64(x89, 0xffffffffffffffff)
+	var x97 uint64
+	var x98 uint64
+	x98, x97 = bits.Mul64(x89, 0xfffffffffffffffe)
+	var x99 uint64
+	var x100 uint64
+	x100, x99 = bits.Mul64(x89, 0xffffffff00000000)
+	var x101 uint64
+	var x102 uint64
+	x102, x101 = bits.Mul64(x89, 0xffffffff)
+	var x103 uint64
+	var x104 uint64
+	x103, x104 = bits.Add64(x102, x99, uint64(0x0))
+	var x105 uint64
+	var x106 uint64
+	x105, x106 = bits.Add64(x100, x97, uint64(p384Uint1(x104)))
+	var x107 uint64
+	var x108 uint64
+	x107, x108 = bits.Add64(x98, x95, uint64(p384Uint1(x106)))
+	var x109 uint64
+	var x110 uint64
+	x109, x110 = bits.Add64(x96, x93, uint64(p384Uint1(x108)))
+	var x111 uint64
+	var x112 uint64
+	x111, x112 = bits.Add64(x94, x91, uint64(p384Uint1(x110)))
+	var x114 uint64
+	_, x114 = bits.Add64(x77, x101, uint64(0x0))
+	var x115 uint64
+	var x116 uint64
+	x115, x116 = bits.Add64(x79, x103, uint64(p384Uint1(x114)))
+	var x117 uint64
+	var x118 uint64
+	x117, x118 = bits.Add64(x81, x105, uint64(p384Uint1(x116)))
+	var x119 uint64
+	var x120 uint64
+	x119, x120 = bits.Add64(x83, x107, uint64(p384Uint1(x118)))
+	var x121 uint64
+	var x122 uint64
+	x121, x122 = bits.Add64(x85, x109, uint64(p384Uint1(x120)))
+	var x123 uint64
+	var x124 uint64
+	x123, x124 = bits.Add64(x87, x111, uint64(p384Uint1(x122)))
+	var x125 uint64
+	var x126 uint64
+	x125, x126 = bits.Add64((uint64(p384Uint1(x88)) + uint64(p384Uint1(x60))), (uint64(p384Uint1(x112)) + x92), uint64(p384Uint1(x124)))
+	var x127 uint64
+	var x128 uint64
+	x128, x127 = bits.Mul64(x2, 0x200000000)
+	var x129 uint64
+	var x130 uint64
+	x130, x129 = bits.Mul64(x2, 0xfffffffe00000000)
+	var x131 uint64
+	var x132 uint64
+	x132, x131 = bits.Mul64(x2, 0x200000000)
+	var x133 uint64
+	var x134 uint64
+	x134, x133 = bits.Mul64(x2, 0xfffffffe00000001)
+	var x135 uint64
+	var x136 uint64
+	x135, x136 = bits.Add64(x134, x131, uint64(0x0))
+	var x137 uint64
+	var x138 uint64
+	x137, x138 = bits.Add64(x132, x129, uint64(p384Uint1(x136)))
+	var x139 uint64
+	var x140 uint64
+	x139, x140 = bits.Add64(x130, x127, uint64(p384Uint1(x138)))
+	var x141 uint64
+	var x142 uint64
+	x141, x142 = bits.Add64(x128, x2, uint64(p384Uint1(x140)))
+	var x143 uint64
+	var x144 uint64
+	x143, x144 = bits.Add64(x115, x133, uint64(0x0))
+	var x145 uint64
+	var x146 uint64
+	x145, x146 = bits.Add64(x117, x135, uint64(p384Uint1(x144)))
+	var x147 uint64
+	var x148 uint64
+	x147, x148 = bits.Add64(x119, x137, uint64(p384Uint1(x146)))
+	var x149 uint64
+	var x150 uint64
+	x149, x150 = bits.Add64(x121, x139, uint64(p384Uint1(x148)))
+	var x151 uint64
+	var x152 uint64
+	x151, x152 = bits.Add64(x123, x141, uint64(p384Uint1(x150)))
+	var x153 uint64
+	var x154 uint64
+	x153, x154 = bits.Add64(x125, uint64(p384Uint1(x142)), uint64(p384Uint1(x152)))
+	var x155 uint64
+	_, x155 = bits.Mul64(x143, 0x100000001)
+	var x157 uint64
+	var x158 uint64
+	x158, x157 = bits.Mul64(x155, 0xffffffffffffffff)
+	var x159 uint64
+	var x160 uint64
+	x160, x159 = bits.Mul64(x155, 0xffffffffffffffff)
+	var x161 uint64
+	var x162 uint64
+	x162, x161 = bits.Mul64(x155, 0xffffffffffffffff)
+	var x163 uint64
+	var x164 uint64
+	x164, x163 = bits.Mul64(x155, 0xfffffffffffffffe)
+	var x165 uint64
+	var x166 uint64
+	x166, x165 = bits.Mul64(x155, 0xffffffff00000000)
+	var x167 uint64
+	var x168 uint64
+	x168, x167 = bits.Mul64(x155, 0xffffffff)
+	var x169 uint64
+	var x170 uint64
+	x169, x170 = bits.Add64(x168, x165, uint64(0x0))
+	var x171 uint64
+	var x172 uint64
+	x171, x172 = bits.Add64(x166, x163, uint64(p384Uint1(x170)))
+	var x173 uint64
+	var x174 uint64
+	x173, x174 = bits.Add64(x164, x161, uint64(p384Uint1(x172)))
+	var x175 uint64
+	var x176 uint64
+	x175, x176 = bits.Add64(x162, x159, uint64(p384Uint1(x174)))
+	var x177 uint64
+	var x178 uint64
+	x177, x178 = bits.Add64(x160, x157, uint64(p384Uint1(x176)))
+	var x180 uint64
+	_, x180 = bits.Add64(x143, x167, uint64(0x0))
+	var x181 uint64
+	var x182 uint64
+	x181, x182 = bits.Add64(x145, x169, uint64(p384Uint1(x180)))
+	var x183 uint64
+	var x184 uint64
+	x183, x184 = bits.Add64(x147, x171, uint64(p384Uint1(x182)))
+	var x185 uint64
+	var x186 uint64
+	x185, x186 = bits.Add64(x149, x173, uint64(p384Uint1(x184)))
+	var x187 uint64
+	var x188 uint64
+	x187, x188 = bits.Add64(x151, x175, uint64(p384Uint1(x186)))
+	var x189 uint64
+	var x190 uint64
+	x189, x190 = bits.Add64(x153, x177, uint64(p384Uint1(x188)))
+	var x191 uint64
+	var x192 uint64
+	x191, x192 = bits.Add64((uint64(p384Uint1(x154)) + uint64(p384Uint1(x126))), (uint64(p384Uint1(x178)) + x158), uint64(p384Uint1(x190)))
+	var x193 uint64
+	var x194 uint64
+	x194, x193 = bits.Mul64(x3, 0x200000000)
+	var x195 uint64
+	var x196 uint64
+	x196, x195 = bits.Mul64(x3, 0xfffffffe00000000)
+	var x197 uint64
+	var x198 uint64
+	x198, x197 = bits.Mul64(x3, 0x200000000)
+	var x199 uint64
+	var x200 uint64
+	x200, x199 = bits.Mul64(x3, 0xfffffffe00000001)
+	var x201 uint64
+	var x202 uint64
+	x201, x202 = bits.Add64(x200, x197, uint64(0x0))
+	var x203 uint64
+	var x204 uint64
+	x203, x204 = bits.Add64(x198, x195, uint64(p384Uint1(x202)))
+	var x205 uint64
+	var x206 uint64
+	x205, x206 = bits.Add64(x196, x193, uint64(p384Uint1(x204)))
+	var x207 uint64
+	var x208 uint64
+	x207, x208 = bits.Add64(x194, x3, uint64(p384Uint1(x206)))
+	var x209 uint64
+	var x210 uint64
+	x209, x210 = bits.Add64(x181, x199, uint64(0x0))
+	var x211 uint64
+	var x212 uint64
+	x211, x212 = bits.Add64(x183, x201, uint64(p384Uint1(x210)))
+	var x213 uint64
+	var x214 uint64
+	x213, x214 = bits.Add64(x185, x203, uint64(p384Uint1(x212)))
+	var x215 uint64
+	var x216 uint64
+	x215, x216 = bits.Add64(x187, x205, uint64(p384Uint1(x214)))
+	var x217 uint64
+	var x218 uint64
+	x217, x218 = bits.Add64(x189, x207, uint64(p384Uint1(x216)))
+	var x219 uint64
+	var x220 uint64
+	x219, x220 = bits.Add64(x191, uint64(p384Uint1(x208)), uint64(p384Uint1(x218)))
+	var x221 uint64
+	_, x221 = bits.Mul64(x209, 0x100000001)
+	var x223 uint64
+	var x224 uint64
+	x224, x223 = bits.Mul64(x221, 0xffffffffffffffff)
+	var x225 uint64
+	var x226 uint64
+	x226, x225 = bits.Mul64(x221, 0xffffffffffffffff)
+	var x227 uint64
+	var x228 uint64
+	x228, x227 = bits.Mul64(x221, 0xffffffffffffffff)
+	var x229 uint64
+	var x230 uint64
+	x230, x229 = bits.Mul64(x221, 0xfffffffffffffffe)
+	var x231 uint64
+	var x232 uint64
+	x232, x231 = bits.Mul64(x221, 0xffffffff00000000)
+	var x233 uint64
+	var x234 uint64
+	x234, x233 = bits.Mul64(x221, 0xffffffff)
+	var x235 uint64
+	var x236 uint64
+	x235, x236 = bits.Add64(x234, x231, uint64(0x0))
+	var x237 uint64
+	var x238 uint64
+	x237, x238 = bits.Add64(x232, x229, uint64(p384Uint1(x236)))
+	var x239 uint64
+	var x240 uint64
+	x239, x240 = bits.Add64(x230, x227, uint64(p384Uint1(x238)))
+	var x241 uint64
+	var x242 uint64
+	x241, x242 = bits.Add64(x228, x225, uint64(p384Uint1(x240)))
+	var x243 uint64
+	var x244 uint64
+	x243, x244 = bits.Add64(x226, x223, uint64(p384Uint1(x242)))
+	var x246 uint64
+	_, x246 = bits.Add64(x209, x233, uint64(0x0))
+	var x247 uint64
+	var x248 uint64
+	x247, x248 = bits.Add64(x211, x235, uint64(p384Uint1(x246)))
+	var x249 uint64
+	var x250 uint64
+	x249, x250 = bits.Add64(x213, x237, uint64(p384Uint1(x248)))
+	var x251 uint64
+	var x252 uint64
+	x251, x252 = bits.Add64(x215, x239, uint64(p384Uint1(x250)))
+	var x253 uint64
+	var x254 uint64
+	x253, x254 = bits.Add64(x217, x241, uint64(p384Uint1(x252)))
+	var x255 uint64
+	var x256 uint64
+	x255, x256 = bits.Add64(x219, x243, uint64(p384Uint1(x254)))
+	var x257 uint64
+	var x258 uint64
+	x257, x258 = bits.Add64((uint64(p384Uint1(x220)) + uint64(p384Uint1(x192))), (uint64(p384Uint1(x244)) + x224), uint64(p384Uint1(x256)))
+	var x259 uint64
+	var x260 uint64
+	x260, x259 = bits.Mul64(x4, 0x200000000)
+	var x261 uint64
+	var x262 uint64
+	x262, x261 = bits.Mul64(x4, 0xfffffffe00000000)
+	var x263 uint64
+	var x264 uint64
+	x264, x263 = bits.Mul64(x4, 0x200000000)
+	var x265 uint64
+	var x266 uint64
+	x266, x265 = bits.Mul64(x4, 0xfffffffe00000001)
+	var x267 uint64
+	var x268 uint64
+	x267, x268 = bits.Add64(x266, x263, uint64(0x0))
+	var x269 uint64
+	var x270 uint64
+	x269, x270 = bits.Add64(x264, x261, uint64(p384Uint1(x268)))
+	var x271 uint64
+	var x272 uint64
+	x271, x272 = bits.Add64(x262, x259, uint64(p384Uint1(x270)))
+	var x273 uint64
+	var x274 uint64
+	x273, x274 = bits.Add64(x260, x4, uint64(p384Uint1(x272)))
+	var x275 uint64
+	var x276 uint64
+	x275, x276 = bits.Add64(x247, x265, uint64(0x0))
+	var x277 uint64
+	var x278 uint64
+	x277, x278 = bits.Add64(x249, x267, uint64(p384Uint1(x276)))
+	var x279 uint64
+	var x280 uint64
+	x279, x280 = bits.Add64(x251, x269, uint64(p384Uint1(x278)))
+	var x281 uint64
+	var x282 uint64
+	x281, x282 = bits.Add64(x253, x271, uint64(p384Uint1(x280)))
+	var x283 uint64
+	var x284 uint64
+	x283, x284 = bits.Add64(x255, x273, uint64(p384Uint1(x282)))
+	var x285 uint64
+	var x286 uint64
+	x285, x286 = bits.Add64(x257, uint64(p384Uint1(x274)), uint64(p384Uint1(x284)))
+	var x287 uint64
+	_, x287 = bits.Mul64(x275, 0x100000001)
+	var x289 uint64
+	var x290 uint64
+	x290, x289 = bits.Mul64(x287, 0xffffffffffffffff)
+	var x291 uint64
+	var x292 uint64
+	x292, x291 = bits.Mul64(x287, 0xffffffffffffffff)
+	var x293 uint64
+	var x294 uint64
+	x294, x293 = bits.Mul64(x287, 0xffffffffffffffff)
+	var x295 uint64
+	var x296 uint64
+	x296, x295 = bits.Mul64(x287, 0xfffffffffffffffe)
+	var x297 uint64
+	var x298 uint64
+	x298, x297 = bits.Mul64(x287, 0xffffffff00000000)
+	var x299 uint64
+	var x300 uint64
+	x300, x299 = bits.Mul64(x287, 0xffffffff)
+	var x301 uint64
+	var x302 uint64
+	x301, x302 = bits.Add64(x300, x297, uint64(0x0))
+	var x303 uint64
+	var x304 uint64
+	x303, x304 = bits.Add64(x298, x295, uint64(p384Uint1(x302)))
+	var x305 uint64
+	var x306 uint64
+	x305, x306 = bits.Add64(x296, x293, uint64(p384Uint1(x304)))
+	var x307 uint64
+	var x308 uint64
+	x307, x308 = bits.Add64(x294, x291, uint64(p384Uint1(x306)))
+	var x309 uint64
+	var x310 uint64
+	x309, x310 = bits.Add64(x292, x289, uint64(p384Uint1(x308)))
+	var x312 uint64
+	_, x312 = bits.Add64(x275, x299, uint64(0x0))
+	var x313 uint64
+	var x314 uint64
+	x313, x314 = bits.Add64(x277, x301, uint64(p384Uint1(x312)))
+	var x315 uint64
+	var x316 uint64
+	x315, x316 = bits.Add64(x279, x303, uint64(p384Uint1(x314)))
+	var x317 uint64
+	var x318 uint64
+	x317, x318 = bits.Add64(x281, x305, uint64(p384Uint1(x316)))
+	var x319 uint64
+	var x320 uint64
+	x319, x320 = bits.Add64(x283, x307, uint64(p384Uint1(x318)))
+	var x321 uint64
+	var x322 uint64
+	x321, x322 = bits.Add64(x285, x309, uint64(p384Uint1(x320)))
+	var x323 uint64
+	var x324 uint64
+	x323, x324 = bits.Add64((uint64(p384Uint1(x286)) + uint64(p384Uint1(x258))), (uint64(p384Uint1(x310)) + x290), uint64(p384Uint1(x322)))
+	var x325 uint64
+	var x326 uint64
+	x326, x325 = bits.Mul64(x5, 0x200000000)
+	var x327 uint64
+	var x328 uint64
+	x328, x327 = bits.Mul64(x5, 0xfffffffe00000000)
+	var x329 uint64
+	var x330 uint64
+	x330, x329 = bits.Mul64(x5, 0x200000000)
+	var x331 uint64
+	var x332 uint64
+	x332, x331 = bits.Mul64(x5, 0xfffffffe00000001)
+	var x333 uint64
+	var x334 uint64
+	x333, x334 = bits.Add64(x332, x329, uint64(0x0))
+	var x335 uint64
+	var x336 uint64
+	x335, x336 = bits.Add64(x330, x327, uint64(p384Uint1(x334)))
+	var x337 uint64
+	var x338 uint64
+	x337, x338 = bits.Add64(x328, x325, uint64(p384Uint1(x336)))
+	var x339 uint64
+	var x340 uint64
+	x339, x340 = bits.Add64(x326, x5, uint64(p384Uint1(x338)))
+	var x341 uint64
+	var x342 uint64
+	x341, x342 = bits.Add64(x313, x331, uint64(0x0))
+	var x343 uint64
+	var x344 uint64
+	x343, x344 = bits.Add64(x315, x333, uint64(p384Uint1(x342)))
+	var x345 uint64
+	var x346 uint64
+	x345, x346 = bits.Add64(x317, x335, uint64(p384Uint1(x344)))
+	var x347 uint64
+	var x348 uint64
+	x347, x348 = bits.Add64(x319, x337, uint64(p384Uint1(x346)))
+	var x349 uint64
+	var x350 uint64
+	x349, x350 = bits.Add64(x321, x339, uint64(p384Uint1(x348)))
+	var x351 uint64
+	var x352 uint64
+	x351, x352 = bits.Add64(x323, uint64(p384Uint1(x340)), uint64(p384Uint1(x350)))
+	var x353 uint64
+	_, x353 = bits.Mul64(x341, 0x100000001)
+	var x355 uint64
+	var x356 uint64
+	x356, x355 = bits.Mul64(x353, 0xffffffffffffffff)
+	var x357 uint64
+	var x358 uint64
+	x358, x357 = bits.Mul64(x353, 0xffffffffffffffff)
+	var x359 uint64
+	var x360 uint64
+	x360, x359 = bits.Mul64(x353, 0xffffffffffffffff)
+	var x361 uint64
+	var x362 uint64
+	x362, x361 = bits.Mul64(x353, 0xfffffffffffffffe)
+	var x363 uint64
+	var x364 uint64
+	x364, x363 = bits.Mul64(x353, 0xffffffff00000000)
+	var x365 uint64
+	var x366 uint64
+	x366, x365 = bits.Mul64(x353, 0xffffffff)
+	var x367 uint64
+	var x368 uint64
+	x367, x368 = bits.Add64(x366, x363, uint64(0x0))
+	var x369 uint64
+	var x370 uint64
+	x369, x370 = bits.Add64(x364, x361, uint64(p384Uint1(x368)))
+	var x371 uint64
+	var x372 uint64
+	x371, x372 = bits.Add64(x362, x359, uint64(p384Uint1(x370)))
+	var x373 uint64
+	var x374 uint64
+	x373, x374 = bits.Add64(x360, x357, uint64(p384Uint1(x372)))
+	var x375 uint64
+	var x376 uint64
+	x375, x376 = bits.Add64(x358, x355, uint64(p384Uint1(x374)))
+	var x378 uint64
+	_, x378 = bits.Add64(x341, x365, uint64(0x0))
+	var x379 uint64
+	var x380 uint64
+	x379, x380 = bits.Add64(x343, x367, uint64(p384Uint1(x378)))
+	var x381 uint64
+	var x382 uint64
+	x381, x382 = bits.Add64(x345, x369, uint64(p384Uint1(x380)))
+	var x383 uint64
+	var x384 uint64
+	x383, x384 = bits.Add64(x347, x371, uint64(p384Uint1(x382)))
+	var x385 uint64
+	var x386 uint64
+	x385, x386 = bits.Add64(x349, x373, uint64(p384Uint1(x384)))
+	var x387 uint64
+	var x388 uint64
+	x387, x388 = bits.Add64(x351, x375, uint64(p384Uint1(x386)))
+	var x389 uint64
+	var x390 uint64
+	x389, x390 = bits.Add64((uint64(p384Uint1(x352)) + uint64(p384Uint1(x324))), (uint64(p384Uint1(x376)) + x356), uint64(p384Uint1(x388)))
+	var x391 uint64
+	var x392 uint64
+	x391, x392 = bits.Sub64(x379, 0xffffffff, uint64(0x0))
+	var x393 uint64
+	var x394 uint64
+	x393, x394 = bits.Sub64(x381, 0xffffffff00000000, uint64(p384Uint1(x392)))
+	var x395 uint64
+	var x396 uint64
+	x395, x396 = bits.Sub64(x383, 0xfffffffffffffffe, uint64(p384Uint1(x394)))
+	var x397 uint64
+	var x398 uint64
+	x397, x398 = bits.Sub64(x385, 0xffffffffffffffff, uint64(p384Uint1(x396)))
+	var x399 uint64
+	var x400 uint64
+	x399, x400 = bits.Sub64(x387, 0xffffffffffffffff, uint64(p384Uint1(x398)))
+	var x401 uint64
+	var x402 uint64
+	x401, x402 = bits.Sub64(x389, 0xffffffffffffffff, uint64(p384Uint1(x400)))
+	var x404 uint64
+	_, x404 = bits.Sub64(uint64(p384Uint1(x390)), uint64(0x0), uint64(p384Uint1(x402)))
+	var x405 uint64
+	p384CmovznzU64(&x405, p384Uint1(x404), x391, x379)
+	var x406 uint64
+	p384CmovznzU64(&x406, p384Uint1(x404), x393, x381)
+	var x407 uint64
+	p384CmovznzU64(&x407, p384Uint1(x404), x395, x383)
+	var x408 uint64
+	p384CmovznzU64(&x408, p384Uint1(x404), x397, x385)
+	var x409 uint64
+	p384CmovznzU64(&x409, p384Uint1(x404), x399, x387)
+	var x410 uint64
+	p384CmovznzU64(&x410, p384Uint1(x404), x401, x389)
+	out1[0] = x405
+	out1[1] = x406
+	out1[2] = x407
+	out1[3] = x408
+	out1[4] = x409
+	out1[5] = x410
+}
+
+// p384Selectznz is a multi-limb conditional select.
+//
+// Postconditions:
+//
+//	eval out1 = (if arg1 = 0 then eval arg2 else eval arg3)
+//
+// Input Bounds:
+//
+//	arg1: [0x0 ~> 0x1]
+//	arg2: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
+//	arg3: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
+//
+// Output Bounds:
+//
+//	out1: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
+func p384Selectznz(out1 *[6]uint64, arg1 p384Uint1, arg2 *[6]uint64, arg3 *[6]uint64) {
+	var x1 uint64
+	p384CmovznzU64(&x1, arg1, arg2[0], arg3[0])
+	var x2 uint64
+	p384CmovznzU64(&x2, arg1, arg2[1], arg3[1])
+	var x3 uint64
+	p384CmovznzU64(&x3, arg1, arg2[2], arg3[2])
+	var x4 uint64
+	p384CmovznzU64(&x4, arg1, arg2[3], arg3[3])
+	var x5 uint64
+	p384CmovznzU64(&x5, arg1, arg2[4], arg3[4])
+	var x6 uint64
+	p384CmovznzU64(&x6, arg1, arg2[5], arg3[5])
+	out1[0] = x1
+	out1[1] = x2
+	out1[2] = x3
+	out1[3] = x4
+	out1[4] = x5
+	out1[5] = x6
+}
+
+// p384ToBytes serializes a field element NOT in the Montgomery domain to bytes in little-endian order.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//
+// Postconditions:
+//
+//	out1 = map (λ x, ⌊((eval arg1 mod m) mod 2^(8 * (x + 1))) / 2^(8 * x)⌋) [0..47]
+//
+// Input Bounds:
+//
+//	arg1: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
+//
+// Output Bounds:
+//
+//	out1: [[0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff]]
+func p384ToBytes(out1 *[48]uint8, arg1 *[6]uint64) {
+	x1 := arg1[5]
+	x2 := arg1[4]
+	x3 := arg1[3]
+	x4 := arg1[2]
+	x5 := arg1[1]
+	x6 := arg1[0]
+	x7 := (uint8(x6) & 0xff)
+	x8 := (x6 >> 8)
+	x9 := (uint8(x8) & 0xff)
+	x10 := (x8 >> 8)
+	x11 := (uint8(x10) & 0xff)
+	x12 := (x10 >> 8)
+	x13 := (uint8(x12) & 0xff)
+	x14 := (x12 >> 8)
+	x15 := (uint8(x14) & 0xff)
+	x16 := (x14 >> 8)
+	x17 := (uint8(x16) & 0xff)
+	x18 := (x16 >> 8)
+	x19 := (uint8(x18) & 0xff)
+	x20 := uint8((x18 >> 8))
+	x21 := (uint8(x5) & 0xff)
+	x22 := (x5 >> 8)
+	x23 := (uint8(x22) & 0xff)
+	x24 := (x22 >> 8)
+	x25 := (uint8(x24) & 0xff)
+	x26 := (x24 >> 8)
+	x27 := (uint8(x26) & 0xff)
+	x28 := (x26 >> 8)
+	x29 := (uint8(x28) & 0xff)
+	x30 := (x28 >> 8)
+	x31 := (uint8(x30) & 0xff)
+	x32 := (x30 >> 8)
+	x33 := (uint8(x32) & 0xff)
+	x34 := uint8((x32 >> 8))
+	x35 := (uint8(x4) & 0xff)
+	x36 := (x4 >> 8)
+	x37 := (uint8(x36) & 0xff)
+	x38 := (x36 >> 8)
+	x39 := (uint8(x38) & 0xff)
+	x40 := (x38 >> 8)
+	x41 := (uint8(x40) & 0xff)
+	x42 := (x40 >> 8)
+	x43 := (uint8(x42) & 0xff)
+	x44 := (x42 >> 8)
+	x45 := (uint8(x44) & 0xff)
+	x46 := (x44 >> 8)
+	x47 := (uint8(x46) & 0xff)
+	x48 := uint8((x46 >> 8))
+	x49 := (uint8(x3) & 0xff)
+	x50 := (x3 >> 8)
+	x51 := (uint8(x50) & 0xff)
+	x52 := (x50 >> 8)
+	x53 := (uint8(x52) & 0xff)
+	x54 := (x52 >> 8)
+	x55 := (uint8(x54) & 0xff)
+	x56 := (x54 >> 8)
+	x57 := (uint8(x56) & 0xff)
+	x58 := (x56 >> 8)
+	x59 := (uint8(x58) & 0xff)
+	x60 := (x58 >> 8)
+	x61 := (uint8(x60) & 0xff)
+	x62 := uint8((x60 >> 8))
+	x63 := (uint8(x2) & 0xff)
+	x64 := (x2 >> 8)
+	x65 := (uint8(x64) & 0xff)
+	x66 := (x64 >> 8)
+	x67 := (uint8(x66) & 0xff)
+	x68 := (x66 >> 8)
+	x69 := (uint8(x68) & 0xff)
+	x70 := (x68 >> 8)
+	x71 := (uint8(x70) & 0xff)
+	x72 := (x70 >> 8)
+	x73 := (uint8(x72) & 0xff)
+	x74 := (x72 >> 8)
+	x75 := (uint8(x74) & 0xff)
+	x76 := uint8((x74 >> 8))
+	x77 := (uint8(x1) & 0xff)
+	x78 := (x1 >> 8)
+	x79 := (uint8(x78) & 0xff)
+	x80 := (x78 >> 8)
+	x81 := (uint8(x80) & 0xff)
+	x82 := (x80 >> 8)
+	x83 := (uint8(x82) & 0xff)
+	x84 := (x82 >> 8)
+	x85 := (uint8(x84) & 0xff)
+	x86 := (x84 >> 8)
+	x87 := (uint8(x86) & 0xff)
+	x88 := (x86 >> 8)
+	x89 := (uint8(x88) & 0xff)
+	x90 := uint8((x88 >> 8))
+	out1[0] = x7
+	out1[1] = x9
+	out1[2] = x11
+	out1[3] = x13
+	out1[4] = x15
+	out1[5] = x17
+	out1[6] = x19
+	out1[7] = x20
+	out1[8] = x21
+	out1[9] = x23
+	out1[10] = x25
+	out1[11] = x27
+	out1[12] = x29
+	out1[13] = x31
+	out1[14] = x33
+	out1[15] = x34
+	out1[16] = x35
+	out1[17] = x37
+	out1[18] = x39
+	out1[19] = x41
+	out1[20] = x43
+	out1[21] = x45
+	out1[22] = x47
+	out1[23] = x48
+	out1[24] = x49
+	out1[25] = x51
+	out1[26] = x53
+	out1[27] = x55
+	out1[28] = x57
+	out1[29] = x59
+	out1[30] = x61
+	out1[31] = x62
+	out1[32] = x63
+	out1[33] = x65
+	out1[34] = x67
+	out1[35] = x69
+	out1[36] = x71
+	out1[37] = x73
+	out1[38] = x75
+	out1[39] = x76
+	out1[40] = x77
+	out1[41] = x79
+	out1[42] = x81
+	out1[43] = x83
+	out1[44] = x85
+	out1[45] = x87
+	out1[46] = x89
+	out1[47] = x90
+}
+
+// p384FromBytes deserializes a field element NOT in the Montgomery domain from bytes in little-endian order.
+//
+// Preconditions:
+//
+//	0 ≤ bytes_eval arg1 < m
+//
+// Postconditions:
+//
+//	eval out1 mod m = bytes_eval arg1 mod m
+//	0 ≤ eval out1 < m
+//
+// Input Bounds:
+//
+//	arg1: [[0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff]]
+//
+// Output Bounds:
+//
+//	out1: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
+func p384FromBytes(out1 *[6]uint64, arg1 *[48]uint8) {
+	x1 := (uint64(arg1[47]) << 56)
+	x2 := (uint64(arg1[46]) << 48)
+	x3 := (uint64(arg1[45]) << 40)
+	x4 := (uint64(arg1[44]) << 32)
+	x5 := (uint64(arg1[43]) << 24)
+	x6 := (uint64(arg1[42]) << 16)
+	x7 := (uint64(arg1[41]) << 8)
+	x8 := arg1[40]
+	x9 := (uint64(arg1[39]) << 56)
+	x10 := (uint64(arg1[38]) << 48)
+	x11 := (uint64(arg1[37]) << 40)
+	x12 := (uint64(arg1[36]) << 32)
+	x13 := (uint64(arg1[35]) << 24)
+	x14 := (uint64(arg1[34]) << 16)
+	x15 := (uint64(arg1[33]) << 8)
+	x16 := arg1[32]
+	x17 := (uint64(arg1[31]) << 56)
+	x18 := (uint64(arg1[30]) << 48)
+	x19 := (uint64(arg1[29]) << 40)
+	x20 := (uint64(arg1[28]) << 32)
+	x21 := (uint64(arg1[27]) << 24)
+	x22 := (uint64(arg1[26]) << 16)
+	x23 := (uint64(arg1[25]) << 8)
+	x24 := arg1[24]
+	x25 := (uint64(arg1[23]) << 56)
+	x26 := (uint64(arg1[22]) << 48)
+	x27 := (uint64(arg1[21]) << 40)
+	x28 := (uint64(arg1[20]) << 32)
+	x29 := (uint64(arg1[19]) << 24)
+	x30 := (uint64(arg1[18]) << 16)
+	x31 := (uint64(arg1[17]) << 8)
+	x32 := arg1[16]
+	x33 := (uint64(arg1[15]) << 56)
+	x34 := (uint64(arg1[14]) << 48)
+	x35 := (uint64(arg1[13]) << 40)
+	x36 := (uint64(arg1[12]) << 32)
+	x37 := (uint64(arg1[11]) << 24)
+	x38 := (uint64(arg1[10]) << 16)
+	x39 := (uint64(arg1[9]) << 8)
+	x40 := arg1[8]
+	x41 := (uint64(arg1[7]) << 56)
+	x42 := (uint64(arg1[6]) << 48)
+	x43 := (uint64(arg1[5]) << 40)
+	x44 := (uint64(arg1[4]) << 32)
+	x45 := (uint64(arg1[3]) << 24)
+	x46 := (uint64(arg1[2]) << 16)
+	x47 := (uint64(arg1[1]) << 8)
+	x48 := arg1[0]
+	x49 := (x47 + uint64(x48))
+	x50 := (x46 + x49)
+	x51 := (x45 + x50)
+	x52 := (x44 + x51)
+	x53 := (x43 + x52)
+	x54 := (x42 + x53)
+	x55 := (x41 + x54)
+	x56 := (x39 + uint64(x40))
+	x57 := (x38 + x56)
+	x58 := (x37 + x57)
+	x59 := (x36 + x58)
+	x60 := (x35 + x59)
+	x61 := (x34 + x60)
+	x62 := (x33 + x61)
+	x63 := (x31 + uint64(x32))
+	x64 := (x30 + x63)
+	x65 := (x29 + x64)
+	x66 := (x28 + x65)
+	x67 := (x27 + x66)
+	x68 := (x26 + x67)
+	x69 := (x25 + x68)
+	x70 := (x23 + uint64(x24))
+	x71 := (x22 + x70)
+	x72 := (x21 + x71)
+	x73 := (x20 + x72)
+	x74 := (x19 + x73)
+	x75 := (x18 + x74)
+	x76 := (x17 + x75)
+	x77 := (x15 + uint64(x16))
+	x78 := (x14 + x77)
+	x79 := (x13 + x78)
+	x80 := (x12 + x79)
+	x81 := (x11 + x80)
+	x82 := (x10 + x81)
+	x83 := (x9 + x82)
+	x84 := (x7 + uint64(x8))
+	x85 := (x6 + x84)
+	x86 := (x5 + x85)
+	x87 := (x4 + x86)
+	x88 := (x3 + x87)
+	x89 := (x2 + x88)
+	x90 := (x1 + x89)
+	out1[0] = x55
+	out1[1] = x62
+	out1[2] = x69
+	out1[3] = x76
+	out1[4] = x83
+	out1[5] = x90
+}
diff --git a/contrib/go/_std_1.18/src/crypto/elliptic/internal/fiat/p384_invert.go b/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p384_invert.go
index 24169e98d9..24169e98d9 100644
--- a/contrib/go/_std_1.18/src/crypto/elliptic/internal/fiat/p384_invert.go
+++ b/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p384_invert.go
diff --git a/contrib/go/_std_1.18/src/crypto/elliptic/internal/fiat/p521.go b/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p521.go
index 3d12117e49..3d12117e49 100644
--- a/contrib/go/_std_1.18/src/crypto/elliptic/internal/fiat/p521.go
+++ b/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p521.go
diff --git a/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p521_fiat64.go b/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p521_fiat64.go
new file mode 100644
index 0000000000..87a359e88e
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p521_fiat64.go
@@ -0,0 +1,5541 @@
+// Code generated by Fiat Cryptography. DO NOT EDIT.
+//
+// Autogenerated: word_by_word_montgomery --lang Go --no-wide-int --cmovznz-by-mul --relax-primitive-carry-to-bitwidth 32,64 --internal-static --public-function-case camelCase --public-type-case camelCase --private-function-case camelCase --private-type-case camelCase --doc-text-before-function-name '' --doc-newline-before-package-declaration --doc-prepend-header 'Code generated by Fiat Cryptography. DO NOT EDIT.' --package-name fiat --no-prefix-fiat p521 64 '2^521 - 1' mul square add sub one from_montgomery to_montgomery selectznz to_bytes from_bytes
+//
+// curve description: p521
+//
+// machine_wordsize = 64 (from "64")
+//
+// requested operations: mul, square, add, sub, one, from_montgomery, to_montgomery, selectznz, to_bytes, from_bytes
+//
+// m = 0x1ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff (from "2^521 - 1")
+//
+//
+//
+// NOTE: In addition to the bounds specified above each function, all
+//
+//   functions synthesized for this Montgomery arithmetic require the
+//
+//   input to be strictly less than the prime modulus (m), and also
+//
+//   require the input to be in the unique saturated representation.
+//
+//   All functions also ensure that these two properties are true of
+//
+//   return values.
+//
+//
+//
+// Computed values:
+//
+//   eval z = z[0] + (z[1] << 64) + (z[2] << 128) + (z[3] << 192) + (z[4] << 256) + (z[5] << 0x140) + (z[6] << 0x180) + (z[7] << 0x1c0) + (z[8] << 2^9)
+//
+//   bytes_eval z = z[0] + (z[1] << 8) + (z[2] << 16) + (z[3] << 24) + (z[4] << 32) + (z[5] << 40) + (z[6] << 48) + (z[7] << 56) + (z[8] << 64) + (z[9] << 72) + (z[10] << 80) + (z[11] << 88) + (z[12] << 96) + (z[13] << 104) + (z[14] << 112) + (z[15] << 120) + (z[16] << 128) + (z[17] << 136) + (z[18] << 144) + (z[19] << 152) + (z[20] << 160) + (z[21] << 168) + (z[22] << 176) + (z[23] << 184) + (z[24] << 192) + (z[25] << 200) + (z[26] << 208) + (z[27] << 216) + (z[28] << 224) + (z[29] << 232) + (z[30] << 240) + (z[31] << 248) + (z[32] << 256) + (z[33] << 0x108) + (z[34] << 0x110) + (z[35] << 0x118) + (z[36] << 0x120) + (z[37] << 0x128) + (z[38] << 0x130) + (z[39] << 0x138) + (z[40] << 0x140) + (z[41] << 0x148) + (z[42] << 0x150) + (z[43] << 0x158) + (z[44] << 0x160) + (z[45] << 0x168) + (z[46] << 0x170) + (z[47] << 0x178) + (z[48] << 0x180) + (z[49] << 0x188) + (z[50] << 0x190) + (z[51] << 0x198) + (z[52] << 0x1a0) + (z[53] << 0x1a8) + (z[54] << 0x1b0) + (z[55] << 0x1b8) + (z[56] << 0x1c0) + (z[57] << 0x1c8) + (z[58] << 0x1d0) + (z[59] << 0x1d8) + (z[60] << 0x1e0) + (z[61] << 0x1e8) + (z[62] << 0x1f0) + (z[63] << 0x1f8) + (z[64] << 2^9) + (z[65] << 0x208)
+//
+//   twos_complement_eval z = let x1 := z[0] + (z[1] << 64) + (z[2] << 128) + (z[3] << 192) + (z[4] << 256) + (z[5] << 0x140) + (z[6] << 0x180) + (z[7] << 0x1c0) + (z[8] << 2^9) in
+//
+//                            if x1 & (2^576-1) < 2^575 then x1 & (2^576-1) else (x1 & (2^576-1)) - 2^576
+
+package fiat
+
+import "math/bits"
+
+type p521Uint1 uint64 // We use uint64 instead of a more narrow type for performance reasons; see https://github.com/mit-plv/fiat-crypto/pull/1006#issuecomment-892625927
+type p521Int1 int64   // We use uint64 instead of a more narrow type for performance reasons; see https://github.com/mit-plv/fiat-crypto/pull/1006#issuecomment-892625927
+
+// The type p521MontgomeryDomainFieldElement is a field element in the Montgomery domain.
+//
+// Bounds: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
+type p521MontgomeryDomainFieldElement [9]uint64
+
+// The type p521NonMontgomeryDomainFieldElement is a field element NOT in the Montgomery domain.
+//
+// Bounds: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
+type p521NonMontgomeryDomainFieldElement [9]uint64
+
+// p521CmovznzU64 is a single-word conditional move.
+//
+// Postconditions:
+//
+//	out1 = (if arg1 = 0 then arg2 else arg3)
+//
+// Input Bounds:
+//
+//	arg1: [0x0 ~> 0x1]
+//	arg2: [0x0 ~> 0xffffffffffffffff]
+//	arg3: [0x0 ~> 0xffffffffffffffff]
+//
+// Output Bounds:
+//
+//	out1: [0x0 ~> 0xffffffffffffffff]
+func p521CmovznzU64(out1 *uint64, arg1 p521Uint1, arg2 uint64, arg3 uint64) {
+	x1 := (uint64(arg1) * 0xffffffffffffffff)
+	x2 := ((x1 & arg3) | ((^x1) & arg2))
+	*out1 = x2
+}
+
+// p521Mul multiplies two field elements in the Montgomery domain.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//	0 ≤ eval arg2 < m
+//
+// Postconditions:
+//
+//	eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) * eval (from_montgomery arg2)) mod m
+//	0 ≤ eval out1 < m
+func p521Mul(out1 *p521MontgomeryDomainFieldElement, arg1 *p521MontgomeryDomainFieldElement, arg2 *p521MontgomeryDomainFieldElement) {
+	x1 := arg1[1]
+	x2 := arg1[2]
+	x3 := arg1[3]
+	x4 := arg1[4]
+	x5 := arg1[5]
+	x6 := arg1[6]
+	x7 := arg1[7]
+	x8 := arg1[8]
+	x9 := arg1[0]
+	var x10 uint64
+	var x11 uint64
+	x11, x10 = bits.Mul64(x9, arg2[8])
+	var x12 uint64
+	var x13 uint64
+	x13, x12 = bits.Mul64(x9, arg2[7])
+	var x14 uint64
+	var x15 uint64
+	x15, x14 = bits.Mul64(x9, arg2[6])
+	var x16 uint64
+	var x17 uint64
+	x17, x16 = bits.Mul64(x9, arg2[5])
+	var x18 uint64
+	var x19 uint64
+	x19, x18 = bits.Mul64(x9, arg2[4])
+	var x20 uint64
+	var x21 uint64
+	x21, x20 = bits.Mul64(x9, arg2[3])
+	var x22 uint64
+	var x23 uint64
+	x23, x22 = bits.Mul64(x9, arg2[2])
+	var x24 uint64
+	var x25 uint64
+	x25, x24 = bits.Mul64(x9, arg2[1])
+	var x26 uint64
+	var x27 uint64
+	x27, x26 = bits.Mul64(x9, arg2[0])
+	var x28 uint64
+	var x29 uint64
+	x28, x29 = bits.Add64(x27, x24, uint64(0x0))
+	var x30 uint64
+	var x31 uint64
+	x30, x31 = bits.Add64(x25, x22, uint64(p521Uint1(x29)))
+	var x32 uint64
+	var x33 uint64
+	x32, x33 = bits.Add64(x23, x20, uint64(p521Uint1(x31)))
+	var x34 uint64
+	var x35 uint64
+	x34, x35 = bits.Add64(x21, x18, uint64(p521Uint1(x33)))
+	var x36 uint64
+	var x37 uint64
+	x36, x37 = bits.Add64(x19, x16, uint64(p521Uint1(x35)))
+	var x38 uint64
+	var x39 uint64
+	x38, x39 = bits.Add64(x17, x14, uint64(p521Uint1(x37)))
+	var x40 uint64
+	var x41 uint64
+	x40, x41 = bits.Add64(x15, x12, uint64(p521Uint1(x39)))
+	var x42 uint64
+	var x43 uint64
+	x42, x43 = bits.Add64(x13, x10, uint64(p521Uint1(x41)))
+	x44 := (uint64(p521Uint1(x43)) + x11)
+	var x45 uint64
+	var x46 uint64
+	x46, x45 = bits.Mul64(x26, 0x1ff)
+	var x47 uint64
+	var x48 uint64
+	x48, x47 = bits.Mul64(x26, 0xffffffffffffffff)
+	var x49 uint64
+	var x50 uint64
+	x50, x49 = bits.Mul64(x26, 0xffffffffffffffff)
+	var x51 uint64
+	var x52 uint64
+	x52, x51 = bits.Mul64(x26, 0xffffffffffffffff)
+	var x53 uint64
+	var x54 uint64
+	x54, x53 = bits.Mul64(x26, 0xffffffffffffffff)
+	var x55 uint64
+	var x56 uint64
+	x56, x55 = bits.Mul64(x26, 0xffffffffffffffff)
+	var x57 uint64
+	var x58 uint64
+	x58, x57 = bits.Mul64(x26, 0xffffffffffffffff)
+	var x59 uint64
+	var x60 uint64
+	x60, x59 = bits.Mul64(x26, 0xffffffffffffffff)
+	var x61 uint64
+	var x62 uint64
+	x62, x61 = bits.Mul64(x26, 0xffffffffffffffff)
+	var x63 uint64
+	var x64 uint64
+	x63, x64 = bits.Add64(x62, x59, uint64(0x0))
+	var x65 uint64
+	var x66 uint64
+	x65, x66 = bits.Add64(x60, x57, uint64(p521Uint1(x64)))
+	var x67 uint64
+	var x68 uint64
+	x67, x68 = bits.Add64(x58, x55, uint64(p521Uint1(x66)))
+	var x69 uint64
+	var x70 uint64
+	x69, x70 = bits.Add64(x56, x53, uint64(p521Uint1(x68)))
+	var x71 uint64
+	var x72 uint64
+	x71, x72 = bits.Add64(x54, x51, uint64(p521Uint1(x70)))
+	var x73 uint64
+	var x74 uint64
+	x73, x74 = bits.Add64(x52, x49, uint64(p521Uint1(x72)))
+	var x75 uint64
+	var x76 uint64
+	x75, x76 = bits.Add64(x50, x47, uint64(p521Uint1(x74)))
+	var x77 uint64
+	var x78 uint64
+	x77, x78 = bits.Add64(x48, x45, uint64(p521Uint1(x76)))
+	x79 := (uint64(p521Uint1(x78)) + x46)
+	var x81 uint64
+	_, x81 = bits.Add64(x26, x61, uint64(0x0))
+	var x82 uint64
+	var x83 uint64
+	x82, x83 = bits.Add64(x28, x63, uint64(p521Uint1(x81)))
+	var x84 uint64
+	var x85 uint64
+	x84, x85 = bits.Add64(x30, x65, uint64(p521Uint1(x83)))
+	var x86 uint64
+	var x87 uint64
+	x86, x87 = bits.Add64(x32, x67, uint64(p521Uint1(x85)))
+	var x88 uint64
+	var x89 uint64
+	x88, x89 = bits.Add64(x34, x69, uint64(p521Uint1(x87)))
+	var x90 uint64
+	var x91 uint64
+	x90, x91 = bits.Add64(x36, x71, uint64(p521Uint1(x89)))
+	var x92 uint64
+	var x93 uint64
+	x92, x93 = bits.Add64(x38, x73, uint64(p521Uint1(x91)))
+	var x94 uint64
+	var x95 uint64
+	x94, x95 = bits.Add64(x40, x75, uint64(p521Uint1(x93)))
+	var x96 uint64
+	var x97 uint64
+	x96, x97 = bits.Add64(x42, x77, uint64(p521Uint1(x95)))
+	var x98 uint64
+	var x99 uint64
+	x98, x99 = bits.Add64(x44, x79, uint64(p521Uint1(x97)))
+	var x100 uint64
+	var x101 uint64
+	x101, x100 = bits.Mul64(x1, arg2[8])
+	var x102 uint64
+	var x103 uint64
+	x103, x102 = bits.Mul64(x1, arg2[7])
+	var x104 uint64
+	var x105 uint64
+	x105, x104 = bits.Mul64(x1, arg2[6])
+	var x106 uint64
+	var x107 uint64
+	x107, x106 = bits.Mul64(x1, arg2[5])
+	var x108 uint64
+	var x109 uint64
+	x109, x108 = bits.Mul64(x1, arg2[4])
+	var x110 uint64
+	var x111 uint64
+	x111, x110 = bits.Mul64(x1, arg2[3])
+	var x112 uint64
+	var x113 uint64
+	x113, x112 = bits.Mul64(x1, arg2[2])
+	var x114 uint64
+	var x115 uint64
+	x115, x114 = bits.Mul64(x1, arg2[1])
+	var x116 uint64
+	var x117 uint64
+	x117, x116 = bits.Mul64(x1, arg2[0])
+	var x118 uint64
+	var x119 uint64
+	x118, x119 = bits.Add64(x117, x114, uint64(0x0))
+	var x120 uint64
+	var x121 uint64
+	x120, x121 = bits.Add64(x115, x112, uint64(p521Uint1(x119)))
+	var x122 uint64
+	var x123 uint64
+	x122, x123 = bits.Add64(x113, x110, uint64(p521Uint1(x121)))
+	var x124 uint64
+	var x125 uint64
+	x124, x125 = bits.Add64(x111, x108, uint64(p521Uint1(x123)))
+	var x126 uint64
+	var x127 uint64
+	x126, x127 = bits.Add64(x109, x106, uint64(p521Uint1(x125)))
+	var x128 uint64
+	var x129 uint64
+	x128, x129 = bits.Add64(x107, x104, uint64(p521Uint1(x127)))
+	var x130 uint64
+	var x131 uint64
+	x130, x131 = bits.Add64(x105, x102, uint64(p521Uint1(x129)))
+	var x132 uint64
+	var x133 uint64
+	x132, x133 = bits.Add64(x103, x100, uint64(p521Uint1(x131)))
+	x134 := (uint64(p521Uint1(x133)) + x101)
+	var x135 uint64
+	var x136 uint64
+	x135, x136 = bits.Add64(x82, x116, uint64(0x0))
+	var x137 uint64
+	var x138 uint64
+	x137, x138 = bits.Add64(x84, x118, uint64(p521Uint1(x136)))
+	var x139 uint64
+	var x140 uint64
+	x139, x140 = bits.Add64(x86, x120, uint64(p521Uint1(x138)))
+	var x141 uint64
+	var x142 uint64
+	x141, x142 = bits.Add64(x88, x122, uint64(p521Uint1(x140)))
+	var x143 uint64
+	var x144 uint64
+	x143, x144 = bits.Add64(x90, x124, uint64(p521Uint1(x142)))
+	var x145 uint64
+	var x146 uint64
+	x145, x146 = bits.Add64(x92, x126, uint64(p521Uint1(x144)))
+	var x147 uint64
+	var x148 uint64
+	x147, x148 = bits.Add64(x94, x128, uint64(p521Uint1(x146)))
+	var x149 uint64
+	var x150 uint64
+	x149, x150 = bits.Add64(x96, x130, uint64(p521Uint1(x148)))
+	var x151 uint64
+	var x152 uint64
+	x151, x152 = bits.Add64(x98, x132, uint64(p521Uint1(x150)))
+	var x153 uint64
+	var x154 uint64
+	x153, x154 = bits.Add64(uint64(p521Uint1(x99)), x134, uint64(p521Uint1(x152)))
+	var x155 uint64
+	var x156 uint64
+	x156, x155 = bits.Mul64(x135, 0x1ff)
+	var x157 uint64
+	var x158 uint64
+	x158, x157 = bits.Mul64(x135, 0xffffffffffffffff)
+	var x159 uint64
+	var x160 uint64
+	x160, x159 = bits.Mul64(x135, 0xffffffffffffffff)
+	var x161 uint64
+	var x162 uint64
+	x162, x161 = bits.Mul64(x135, 0xffffffffffffffff)
+	var x163 uint64
+	var x164 uint64
+	x164, x163 = bits.Mul64(x135, 0xffffffffffffffff)
+	var x165 uint64
+	var x166 uint64
+	x166, x165 = bits.Mul64(x135, 0xffffffffffffffff)
+	var x167 uint64
+	var x168 uint64
+	x168, x167 = bits.Mul64(x135, 0xffffffffffffffff)
+	var x169 uint64
+	var x170 uint64
+	x170, x169 = bits.Mul64(x135, 0xffffffffffffffff)
+	var x171 uint64
+	var x172 uint64
+	x172, x171 = bits.Mul64(x135, 0xffffffffffffffff)
+	var x173 uint64
+	var x174 uint64
+	x173, x174 = bits.Add64(x172, x169, uint64(0x0))
+	var x175 uint64
+	var x176 uint64
+	x175, x176 = bits.Add64(x170, x167, uint64(p521Uint1(x174)))
+	var x177 uint64
+	var x178 uint64
+	x177, x178 = bits.Add64(x168, x165, uint64(p521Uint1(x176)))
+	var x179 uint64
+	var x180 uint64
+	x179, x180 = bits.Add64(x166, x163, uint64(p521Uint1(x178)))
+	var x181 uint64
+	var x182 uint64
+	x181, x182 = bits.Add64(x164, x161, uint64(p521Uint1(x180)))
+	var x183 uint64
+	var x184 uint64
+	x183, x184 = bits.Add64(x162, x159, uint64(p521Uint1(x182)))
+	var x185 uint64
+	var x186 uint64
+	x185, x186 = bits.Add64(x160, x157, uint64(p521Uint1(x184)))
+	var x187 uint64
+	var x188 uint64
+	x187, x188 = bits.Add64(x158, x155, uint64(p521Uint1(x186)))
+	x189 := (uint64(p521Uint1(x188)) + x156)
+	var x191 uint64
+	_, x191 = bits.Add64(x135, x171, uint64(0x0))
+	var x192 uint64
+	var x193 uint64
+	x192, x193 = bits.Add64(x137, x173, uint64(p521Uint1(x191)))
+	var x194 uint64
+	var x195 uint64
+	x194, x195 = bits.Add64(x139, x175, uint64(p521Uint1(x193)))
+	var x196 uint64
+	var x197 uint64
+	x196, x197 = bits.Add64(x141, x177, uint64(p521Uint1(x195)))
+	var x198 uint64
+	var x199 uint64
+	x198, x199 = bits.Add64(x143, x179, uint64(p521Uint1(x197)))
+	var x200 uint64
+	var x201 uint64
+	x200, x201 = bits.Add64(x145, x181, uint64(p521Uint1(x199)))
+	var x202 uint64
+	var x203 uint64
+	x202, x203 = bits.Add64(x147, x183, uint64(p521Uint1(x201)))
+	var x204 uint64
+	var x205 uint64
+	x204, x205 = bits.Add64(x149, x185, uint64(p521Uint1(x203)))
+	var x206 uint64
+	var x207 uint64
+	x206, x207 = bits.Add64(x151, x187, uint64(p521Uint1(x205)))
+	var x208 uint64
+	var x209 uint64
+	x208, x209 = bits.Add64(x153, x189, uint64(p521Uint1(x207)))
+	x210 := (uint64(p521Uint1(x209)) + uint64(p521Uint1(x154)))
+	var x211 uint64
+	var x212 uint64
+	x212, x211 = bits.Mul64(x2, arg2[8])
+	var x213 uint64
+	var x214 uint64
+	x214, x213 = bits.Mul64(x2, arg2[7])
+	var x215 uint64
+	var x216 uint64
+	x216, x215 = bits.Mul64(x2, arg2[6])
+	var x217 uint64
+	var x218 uint64
+	x218, x217 = bits.Mul64(x2, arg2[5])
+	var x219 uint64
+	var x220 uint64
+	x220, x219 = bits.Mul64(x2, arg2[4])
+	var x221 uint64
+	var x222 uint64
+	x222, x221 = bits.Mul64(x2, arg2[3])
+	var x223 uint64
+	var x224 uint64
+	x224, x223 = bits.Mul64(x2, arg2[2])
+	var x225 uint64
+	var x226 uint64
+	x226, x225 = bits.Mul64(x2, arg2[1])
+	var x227 uint64
+	var x228 uint64
+	x228, x227 = bits.Mul64(x2, arg2[0])
+	var x229 uint64
+	var x230 uint64
+	x229, x230 = bits.Add64(x228, x225, uint64(0x0))
+	var x231 uint64
+	var x232 uint64
+	x231, x232 = bits.Add64(x226, x223, uint64(p521Uint1(x230)))
+	var x233 uint64
+	var x234 uint64
+	x233, x234 = bits.Add64(x224, x221, uint64(p521Uint1(x232)))
+	var x235 uint64
+	var x236 uint64
+	x235, x236 = bits.Add64(x222, x219, uint64(p521Uint1(x234)))
+	var x237 uint64
+	var x238 uint64
+	x237, x238 = bits.Add64(x220, x217, uint64(p521Uint1(x236)))
+	var x239 uint64
+	var x240 uint64
+	x239, x240 = bits.Add64(x218, x215, uint64(p521Uint1(x238)))
+	var x241 uint64
+	var x242 uint64
+	x241, x242 = bits.Add64(x216, x213, uint64(p521Uint1(x240)))
+	var x243 uint64
+	var x244 uint64
+	x243, x244 = bits.Add64(x214, x211, uint64(p521Uint1(x242)))
+	x245 := (uint64(p521Uint1(x244)) + x212)
+	var x246 uint64
+	var x247 uint64
+	x246, x247 = bits.Add64(x192, x227, uint64(0x0))
+	var x248 uint64
+	var x249 uint64
+	x248, x249 = bits.Add64(x194, x229, uint64(p521Uint1(x247)))
+	var x250 uint64
+	var x251 uint64
+	x250, x251 = bits.Add64(x196, x231, uint64(p521Uint1(x249)))
+	var x252 uint64
+	var x253 uint64
+	x252, x253 = bits.Add64(x198, x233, uint64(p521Uint1(x251)))
+	var x254 uint64
+	var x255 uint64
+	x254, x255 = bits.Add64(x200, x235, uint64(p521Uint1(x253)))
+	var x256 uint64
+	var x257 uint64
+	x256, x257 = bits.Add64(x202, x237, uint64(p521Uint1(x255)))
+	var x258 uint64
+	var x259 uint64
+	x258, x259 = bits.Add64(x204, x239, uint64(p521Uint1(x257)))
+	var x260 uint64
+	var x261 uint64
+	x260, x261 = bits.Add64(x206, x241, uint64(p521Uint1(x259)))
+	var x262 uint64
+	var x263 uint64
+	x262, x263 = bits.Add64(x208, x243, uint64(p521Uint1(x261)))
+	var x264 uint64
+	var x265 uint64
+	x264, x265 = bits.Add64(x210, x245, uint64(p521Uint1(x263)))
+	var x266 uint64
+	var x267 uint64
+	x267, x266 = bits.Mul64(x246, 0x1ff)
+	var x268 uint64
+	var x269 uint64
+	x269, x268 = bits.Mul64(x246, 0xffffffffffffffff)
+	var x270 uint64
+	var x271 uint64
+	x271, x270 = bits.Mul64(x246, 0xffffffffffffffff)
+	var x272 uint64
+	var x273 uint64
+	x273, x272 = bits.Mul64(x246, 0xffffffffffffffff)
+	var x274 uint64
+	var x275 uint64
+	x275, x274 = bits.Mul64(x246, 0xffffffffffffffff)
+	var x276 uint64
+	var x277 uint64
+	x277, x276 = bits.Mul64(x246, 0xffffffffffffffff)
+	var x278 uint64
+	var x279 uint64
+	x279, x278 = bits.Mul64(x246, 0xffffffffffffffff)
+	var x280 uint64
+	var x281 uint64
+	x281, x280 = bits.Mul64(x246, 0xffffffffffffffff)
+	var x282 uint64
+	var x283 uint64
+	x283, x282 = bits.Mul64(x246, 0xffffffffffffffff)
+	var x284 uint64
+	var x285 uint64
+	x284, x285 = bits.Add64(x283, x280, uint64(0x0))
+	var x286 uint64
+	var x287 uint64
+	x286, x287 = bits.Add64(x281, x278, uint64(p521Uint1(x285)))
+	var x288 uint64
+	var x289 uint64
+	x288, x289 = bits.Add64(x279, x276, uint64(p521Uint1(x287)))
+	var x290 uint64
+	var x291 uint64
+	x290, x291 = bits.Add64(x277, x274, uint64(p521Uint1(x289)))
+	var x292 uint64
+	var x293 uint64
+	x292, x293 = bits.Add64(x275, x272, uint64(p521Uint1(x291)))
+	var x294 uint64
+	var x295 uint64
+	x294, x295 = bits.Add64(x273, x270, uint64(p521Uint1(x293)))
+	var x296 uint64
+	var x297 uint64
+	x296, x297 = bits.Add64(x271, x268, uint64(p521Uint1(x295)))
+	var x298 uint64
+	var x299 uint64
+	x298, x299 = bits.Add64(x269, x266, uint64(p521Uint1(x297)))
+	x300 := (uint64(p521Uint1(x299)) + x267)
+	var x302 uint64
+	_, x302 = bits.Add64(x246, x282, uint64(0x0))
+	var x303 uint64
+	var x304 uint64
+	x303, x304 = bits.Add64(x248, x284, uint64(p521Uint1(x302)))
+	var x305 uint64
+	var x306 uint64
+	x305, x306 = bits.Add64(x250, x286, uint64(p521Uint1(x304)))
+	var x307 uint64
+	var x308 uint64
+	x307, x308 = bits.Add64(x252, x288, uint64(p521Uint1(x306)))
+	var x309 uint64
+	var x310 uint64
+	x309, x310 = bits.Add64(x254, x290, uint64(p521Uint1(x308)))
+	var x311 uint64
+	var x312 uint64
+	x311, x312 = bits.Add64(x256, x292, uint64(p521Uint1(x310)))
+	var x313 uint64
+	var x314 uint64
+	x313, x314 = bits.Add64(x258, x294, uint64(p521Uint1(x312)))
+	var x315 uint64
+	var x316 uint64
+	x315, x316 = bits.Add64(x260, x296, uint64(p521Uint1(x314)))
+	var x317 uint64
+	var x318 uint64
+	x317, x318 = bits.Add64(x262, x298, uint64(p521Uint1(x316)))
+	var x319 uint64
+	var x320 uint64
+	x319, x320 = bits.Add64(x264, x300, uint64(p521Uint1(x318)))
+	x321 := (uint64(p521Uint1(x320)) + uint64(p521Uint1(x265)))
+	var x322 uint64
+	var x323 uint64
+	x323, x322 = bits.Mul64(x3, arg2[8])
+	var x324 uint64
+	var x325 uint64
+	x325, x324 = bits.Mul64(x3, arg2[7])
+	var x326 uint64
+	var x327 uint64
+	x327, x326 = bits.Mul64(x3, arg2[6])
+	var x328 uint64
+	var x329 uint64
+	x329, x328 = bits.Mul64(x3, arg2[5])
+	var x330 uint64
+	var x331 uint64
+	x331, x330 = bits.Mul64(x3, arg2[4])
+	var x332 uint64
+	var x333 uint64
+	x333, x332 = bits.Mul64(x3, arg2[3])
+	var x334 uint64
+	var x335 uint64
+	x335, x334 = bits.Mul64(x3, arg2[2])
+	var x336 uint64
+	var x337 uint64
+	x337, x336 = bits.Mul64(x3, arg2[1])
+	var x338 uint64
+	var x339 uint64
+	x339, x338 = bits.Mul64(x3, arg2[0])
+	var x340 uint64
+	var x341 uint64
+	x340, x341 = bits.Add64(x339, x336, uint64(0x0))
+	var x342 uint64
+	var x343 uint64
+	x342, x343 = bits.Add64(x337, x334, uint64(p521Uint1(x341)))
+	var x344 uint64
+	var x345 uint64
+	x344, x345 = bits.Add64(x335, x332, uint64(p521Uint1(x343)))
+	var x346 uint64
+	var x347 uint64
+	x346, x347 = bits.Add64(x333, x330, uint64(p521Uint1(x345)))
+	var x348 uint64
+	var x349 uint64
+	x348, x349 = bits.Add64(x331, x328, uint64(p521Uint1(x347)))
+	var x350 uint64
+	var x351 uint64
+	x350, x351 = bits.Add64(x329, x326, uint64(p521Uint1(x349)))
+	var x352 uint64
+	var x353 uint64
+	x352, x353 = bits.Add64(x327, x324, uint64(p521Uint1(x351)))
+	var x354 uint64
+	var x355 uint64
+	x354, x355 = bits.Add64(x325, x322, uint64(p521Uint1(x353)))
+	x356 := (uint64(p521Uint1(x355)) + x323)
+	var x357 uint64
+	var x358 uint64
+	x357, x358 = bits.Add64(x303, x338, uint64(0x0))
+	var x359 uint64
+	var x360 uint64
+	x359, x360 = bits.Add64(x305, x340, uint64(p521Uint1(x358)))
+	var x361 uint64
+	var x362 uint64
+	x361, x362 = bits.Add64(x307, x342, uint64(p521Uint1(x360)))
+	var x363 uint64
+	var x364 uint64
+	x363, x364 = bits.Add64(x309, x344, uint64(p521Uint1(x362)))
+	var x365 uint64
+	var x366 uint64
+	x365, x366 = bits.Add64(x311, x346, uint64(p521Uint1(x364)))
+	var x367 uint64
+	var x368 uint64
+	x367, x368 = bits.Add64(x313, x348, uint64(p521Uint1(x366)))
+	var x369 uint64
+	var x370 uint64
+	x369, x370 = bits.Add64(x315, x350, uint64(p521Uint1(x368)))
+	var x371 uint64
+	var x372 uint64
+	x371, x372 = bits.Add64(x317, x352, uint64(p521Uint1(x370)))
+	var x373 uint64
+	var x374 uint64
+	x373, x374 = bits.Add64(x319, x354, uint64(p521Uint1(x372)))
+	var x375 uint64
+	var x376 uint64
+	x375, x376 = bits.Add64(x321, x356, uint64(p521Uint1(x374)))
+	var x377 uint64
+	var x378 uint64
+	x378, x377 = bits.Mul64(x357, 0x1ff)
+	var x379 uint64
+	var x380 uint64
+	x380, x379 = bits.Mul64(x357, 0xffffffffffffffff)
+	var x381 uint64
+	var x382 uint64
+	x382, x381 = bits.Mul64(x357, 0xffffffffffffffff)
+	var x383 uint64
+	var x384 uint64
+	x384, x383 = bits.Mul64(x357, 0xffffffffffffffff)
+	var x385 uint64
+	var x386 uint64
+	x386, x385 = bits.Mul64(x357, 0xffffffffffffffff)
+	var x387 uint64
+	var x388 uint64
+	x388, x387 = bits.Mul64(x357, 0xffffffffffffffff)
+	var x389 uint64
+	var x390 uint64
+	x390, x389 = bits.Mul64(x357, 0xffffffffffffffff)
+	var x391 uint64
+	var x392 uint64
+	x392, x391 = bits.Mul64(x357, 0xffffffffffffffff)
+	var x393 uint64
+	var x394 uint64
+	x394, x393 = bits.Mul64(x357, 0xffffffffffffffff)
+	var x395 uint64
+	var x396 uint64
+	x395, x396 = bits.Add64(x394, x391, uint64(0x0))
+	var x397 uint64
+	var x398 uint64
+	x397, x398 = bits.Add64(x392, x389, uint64(p521Uint1(x396)))
+	var x399 uint64
+	var x400 uint64
+	x399, x400 = bits.Add64(x390, x387, uint64(p521Uint1(x398)))
+	var x401 uint64
+	var x402 uint64
+	x401, x402 = bits.Add64(x388, x385, uint64(p521Uint1(x400)))
+	var x403 uint64
+	var x404 uint64
+	x403, x404 = bits.Add64(x386, x383, uint64(p521Uint1(x402)))
+	var x405 uint64
+	var x406 uint64
+	x405, x406 = bits.Add64(x384, x381, uint64(p521Uint1(x404)))
+	var x407 uint64
+	var x408 uint64
+	x407, x408 = bits.Add64(x382, x379, uint64(p521Uint1(x406)))
+	var x409 uint64
+	var x410 uint64
+	x409, x410 = bits.Add64(x380, x377, uint64(p521Uint1(x408)))
+	x411 := (uint64(p521Uint1(x410)) + x378)
+	var x413 uint64
+	_, x413 = bits.Add64(x357, x393, uint64(0x0))
+	var x414 uint64
+	var x415 uint64
+	x414, x415 = bits.Add64(x359, x395, uint64(p521Uint1(x413)))
+	var x416 uint64
+	var x417 uint64
+	x416, x417 = bits.Add64(x361, x397, uint64(p521Uint1(x415)))
+	var x418 uint64
+	var x419 uint64
+	x418, x419 = bits.Add64(x363, x399, uint64(p521Uint1(x417)))
+	var x420 uint64
+	var x421 uint64
+	x420, x421 = bits.Add64(x365, x401, uint64(p521Uint1(x419)))
+	var x422 uint64
+	var x423 uint64
+	x422, x423 = bits.Add64(x367, x403, uint64(p521Uint1(x421)))
+	var x424 uint64
+	var x425 uint64
+	x424, x425 = bits.Add64(x369, x405, uint64(p521Uint1(x423)))
+	var x426 uint64
+	var x427 uint64
+	x426, x427 = bits.Add64(x371, x407, uint64(p521Uint1(x425)))
+	var x428 uint64
+	var x429 uint64
+	x428, x429 = bits.Add64(x373, x409, uint64(p521Uint1(x427)))
+	var x430 uint64
+	var x431 uint64
+	x430, x431 = bits.Add64(x375, x411, uint64(p521Uint1(x429)))
+	x432 := (uint64(p521Uint1(x431)) + uint64(p521Uint1(x376)))
+	var x433 uint64
+	var x434 uint64
+	x434, x433 = bits.Mul64(x4, arg2[8])
+	var x435 uint64
+	var x436 uint64
+	x436, x435 = bits.Mul64(x4, arg2[7])
+	var x437 uint64
+	var x438 uint64
+	x438, x437 = bits.Mul64(x4, arg2[6])
+	var x439 uint64
+	var x440 uint64
+	x440, x439 = bits.Mul64(x4, arg2[5])
+	var x441 uint64
+	var x442 uint64
+	x442, x441 = bits.Mul64(x4, arg2[4])
+	var x443 uint64
+	var x444 uint64
+	x444, x443 = bits.Mul64(x4, arg2[3])
+	var x445 uint64
+	var x446 uint64
+	x446, x445 = bits.Mul64(x4, arg2[2])
+	var x447 uint64
+	var x448 uint64
+	x448, x447 = bits.Mul64(x4, arg2[1])
+	var x449 uint64
+	var x450 uint64
+	x450, x449 = bits.Mul64(x4, arg2[0])
+	var x451 uint64
+	var x452 uint64
+	x451, x452 = bits.Add64(x450, x447, uint64(0x0))
+	var x453 uint64
+	var x454 uint64
+	x453, x454 = bits.Add64(x448, x445, uint64(p521Uint1(x452)))
+	var x455 uint64
+	var x456 uint64
+	x455, x456 = bits.Add64(x446, x443, uint64(p521Uint1(x454)))
+	var x457 uint64
+	var x458 uint64
+	x457, x458 = bits.Add64(x444, x441, uint64(p521Uint1(x456)))
+	var x459 uint64
+	var x460 uint64
+	x459, x460 = bits.Add64(x442, x439, uint64(p521Uint1(x458)))
+	var x461 uint64
+	var x462 uint64
+	x461, x462 = bits.Add64(x440, x437, uint64(p521Uint1(x460)))
+	var x463 uint64
+	var x464 uint64
+	x463, x464 = bits.Add64(x438, x435, uint64(p521Uint1(x462)))
+	var x465 uint64
+	var x466 uint64
+	x465, x466 = bits.Add64(x436, x433, uint64(p521Uint1(x464)))
+	x467 := (uint64(p521Uint1(x466)) + x434)
+	var x468 uint64
+	var x469 uint64
+	x468, x469 = bits.Add64(x414, x449, uint64(0x0))
+	var x470 uint64
+	var x471 uint64
+	x470, x471 = bits.Add64(x416, x451, uint64(p521Uint1(x469)))
+	var x472 uint64
+	var x473 uint64
+	x472, x473 = bits.Add64(x418, x453, uint64(p521Uint1(x471)))
+	var x474 uint64
+	var x475 uint64
+	x474, x475 = bits.Add64(x420, x455, uint64(p521Uint1(x473)))
+	var x476 uint64
+	var x477 uint64
+	x476, x477 = bits.Add64(x422, x457, uint64(p521Uint1(x475)))
+	var x478 uint64
+	var x479 uint64
+	x478, x479 = bits.Add64(x424, x459, uint64(p521Uint1(x477)))
+	var x480 uint64
+	var x481 uint64
+	x480, x481 = bits.Add64(x426, x461, uint64(p521Uint1(x479)))
+	var x482 uint64
+	var x483 uint64
+	x482, x483 = bits.Add64(x428, x463, uint64(p521Uint1(x481)))
+	var x484 uint64
+	var x485 uint64
+	x484, x485 = bits.Add64(x430, x465, uint64(p521Uint1(x483)))
+	var x486 uint64
+	var x487 uint64
+	x486, x487 = bits.Add64(x432, x467, uint64(p521Uint1(x485)))
+	var x488 uint64
+	var x489 uint64
+	x489, x488 = bits.Mul64(x468, 0x1ff)
+	var x490 uint64
+	var x491 uint64
+	x491, x490 = bits.Mul64(x468, 0xffffffffffffffff)
+	var x492 uint64
+	var x493 uint64
+	x493, x492 = bits.Mul64(x468, 0xffffffffffffffff)
+	var x494 uint64
+	var x495 uint64
+	x495, x494 = bits.Mul64(x468, 0xffffffffffffffff)
+	var x496 uint64
+	var x497 uint64
+	x497, x496 = bits.Mul64(x468, 0xffffffffffffffff)
+	var x498 uint64
+	var x499 uint64
+	x499, x498 = bits.Mul64(x468, 0xffffffffffffffff)
+	var x500 uint64
+	var x501 uint64
+	x501, x500 = bits.Mul64(x468, 0xffffffffffffffff)
+	var x502 uint64
+	var x503 uint64
+	x503, x502 = bits.Mul64(x468, 0xffffffffffffffff)
+	var x504 uint64
+	var x505 uint64
+	x505, x504 = bits.Mul64(x468, 0xffffffffffffffff)
+	var x506 uint64
+	var x507 uint64
+	x506, x507 = bits.Add64(x505, x502, uint64(0x0))
+	var x508 uint64
+	var x509 uint64
+	x508, x509 = bits.Add64(x503, x500, uint64(p521Uint1(x507)))
+	var x510 uint64
+	var x511 uint64
+	x510, x511 = bits.Add64(x501, x498, uint64(p521Uint1(x509)))
+	var x512 uint64
+	var x513 uint64
+	x512, x513 = bits.Add64(x499, x496, uint64(p521Uint1(x511)))
+	var x514 uint64
+	var x515 uint64
+	x514, x515 = bits.Add64(x497, x494, uint64(p521Uint1(x513)))
+	var x516 uint64
+	var x517 uint64
+	x516, x517 = bits.Add64(x495, x492, uint64(p521Uint1(x515)))
+	var x518 uint64
+	var x519 uint64
+	x518, x519 = bits.Add64(x493, x490, uint64(p521Uint1(x517)))
+	var x520 uint64
+	var x521 uint64
+	x520, x521 = bits.Add64(x491, x488, uint64(p521Uint1(x519)))
+	x522 := (uint64(p521Uint1(x521)) + x489)
+	var x524 uint64
+	_, x524 = bits.Add64(x468, x504, uint64(0x0))
+	var x525 uint64
+	var x526 uint64
+	x525, x526 = bits.Add64(x470, x506, uint64(p521Uint1(x524)))
+	var x527 uint64
+	var x528 uint64
+	x527, x528 = bits.Add64(x472, x508, uint64(p521Uint1(x526)))
+	var x529 uint64
+	var x530 uint64
+	x529, x530 = bits.Add64(x474, x510, uint64(p521Uint1(x528)))
+	var x531 uint64
+	var x532 uint64
+	x531, x532 = bits.Add64(x476, x512, uint64(p521Uint1(x530)))
+	var x533 uint64
+	var x534 uint64
+	x533, x534 = bits.Add64(x478, x514, uint64(p521Uint1(x532)))
+	var x535 uint64
+	var x536 uint64
+	x535, x536 = bits.Add64(x480, x516, uint64(p521Uint1(x534)))
+	var x537 uint64
+	var x538 uint64
+	x537, x538 = bits.Add64(x482, x518, uint64(p521Uint1(x536)))
+	var x539 uint64
+	var x540 uint64
+	x539, x540 = bits.Add64(x484, x520, uint64(p521Uint1(x538)))
+	var x541 uint64
+	var x542 uint64
+	x541, x542 = bits.Add64(x486, x522, uint64(p521Uint1(x540)))
+	x543 := (uint64(p521Uint1(x542)) + uint64(p521Uint1(x487)))
+	var x544 uint64
+	var x545 uint64
+	x545, x544 = bits.Mul64(x5, arg2[8])
+	var x546 uint64
+	var x547 uint64
+	x547, x546 = bits.Mul64(x5, arg2[7])
+	var x548 uint64
+	var x549 uint64
+	x549, x548 = bits.Mul64(x5, arg2[6])
+	var x550 uint64
+	var x551 uint64
+	x551, x550 = bits.Mul64(x5, arg2[5])
+	var x552 uint64
+	var x553 uint64
+	x553, x552 = bits.Mul64(x5, arg2[4])
+	var x554 uint64
+	var x555 uint64
+	x555, x554 = bits.Mul64(x5, arg2[3])
+	var x556 uint64
+	var x557 uint64
+	x557, x556 = bits.Mul64(x5, arg2[2])
+	var x558 uint64
+	var x559 uint64
+	x559, x558 = bits.Mul64(x5, arg2[1])
+	var x560 uint64
+	var x561 uint64
+	x561, x560 = bits.Mul64(x5, arg2[0])
+	var x562 uint64
+	var x563 uint64
+	x562, x563 = bits.Add64(x561, x558, uint64(0x0))
+	var x564 uint64
+	var x565 uint64
+	x564, x565 = bits.Add64(x559, x556, uint64(p521Uint1(x563)))
+	var x566 uint64
+	var x567 uint64
+	x566, x567 = bits.Add64(x557, x554, uint64(p521Uint1(x565)))
+	var x568 uint64
+	var x569 uint64
+	x568, x569 = bits.Add64(x555, x552, uint64(p521Uint1(x567)))
+	var x570 uint64
+	var x571 uint64
+	x570, x571 = bits.Add64(x553, x550, uint64(p521Uint1(x569)))
+	var x572 uint64
+	var x573 uint64
+	x572, x573 = bits.Add64(x551, x548, uint64(p521Uint1(x571)))
+	var x574 uint64
+	var x575 uint64
+	x574, x575 = bits.Add64(x549, x546, uint64(p521Uint1(x573)))
+	var x576 uint64
+	var x577 uint64
+	x576, x577 = bits.Add64(x547, x544, uint64(p521Uint1(x575)))
+	x578 := (uint64(p521Uint1(x577)) + x545)
+	var x579 uint64
+	var x580 uint64
+	x579, x580 = bits.Add64(x525, x560, uint64(0x0))
+	var x581 uint64
+	var x582 uint64
+	x581, x582 = bits.Add64(x527, x562, uint64(p521Uint1(x580)))
+	var x583 uint64
+	var x584 uint64
+	x583, x584 = bits.Add64(x529, x564, uint64(p521Uint1(x582)))
+	var x585 uint64
+	var x586 uint64
+	x585, x586 = bits.Add64(x531, x566, uint64(p521Uint1(x584)))
+	var x587 uint64
+	var x588 uint64
+	x587, x588 = bits.Add64(x533, x568, uint64(p521Uint1(x586)))
+	var x589 uint64
+	var x590 uint64
+	x589, x590 = bits.Add64(x535, x570, uint64(p521Uint1(x588)))
+	var x591 uint64
+	var x592 uint64
+	x591, x592 = bits.Add64(x537, x572, uint64(p521Uint1(x590)))
+	var x593 uint64
+	var x594 uint64
+	x593, x594 = bits.Add64(x539, x574, uint64(p521Uint1(x592)))
+	var x595 uint64
+	var x596 uint64
+	x595, x596 = bits.Add64(x541, x576, uint64(p521Uint1(x594)))
+	var x597 uint64
+	var x598 uint64
+	x597, x598 = bits.Add64(x543, x578, uint64(p521Uint1(x596)))
+	var x599 uint64
+	var x600 uint64
+	x600, x599 = bits.Mul64(x579, 0x1ff)
+	var x601 uint64
+	var x602 uint64
+	x602, x601 = bits.Mul64(x579, 0xffffffffffffffff)
+	var x603 uint64
+	var x604 uint64
+	x604, x603 = bits.Mul64(x579, 0xffffffffffffffff)
+	var x605 uint64
+	var x606 uint64
+	x606, x605 = bits.Mul64(x579, 0xffffffffffffffff)
+	var x607 uint64
+	var x608 uint64
+	x608, x607 = bits.Mul64(x579, 0xffffffffffffffff)
+	var x609 uint64
+	var x610 uint64
+	x610, x609 = bits.Mul64(x579, 0xffffffffffffffff)
+	var x611 uint64
+	var x612 uint64
+	x612, x611 = bits.Mul64(x579, 0xffffffffffffffff)
+	var x613 uint64
+	var x614 uint64
+	x614, x613 = bits.Mul64(x579, 0xffffffffffffffff)
+	var x615 uint64
+	var x616 uint64
+	x616, x615 = bits.Mul64(x579, 0xffffffffffffffff)
+	var x617 uint64
+	var x618 uint64
+	x617, x618 = bits.Add64(x616, x613, uint64(0x0))
+	var x619 uint64
+	var x620 uint64
+	x619, x620 = bits.Add64(x614, x611, uint64(p521Uint1(x618)))
+	var x621 uint64
+	var x622 uint64
+	x621, x622 = bits.Add64(x612, x609, uint64(p521Uint1(x620)))
+	var x623 uint64
+	var x624 uint64
+	x623, x624 = bits.Add64(x610, x607, uint64(p521Uint1(x622)))
+	var x625 uint64
+	var x626 uint64
+	x625, x626 = bits.Add64(x608, x605, uint64(p521Uint1(x624)))
+	var x627 uint64
+	var x628 uint64
+	x627, x628 = bits.Add64(x606, x603, uint64(p521Uint1(x626)))
+	var x629 uint64
+	var x630 uint64
+	x629, x630 = bits.Add64(x604, x601, uint64(p521Uint1(x628)))
+	var x631 uint64
+	var x632 uint64
+	x631, x632 = bits.Add64(x602, x599, uint64(p521Uint1(x630)))
+	x633 := (uint64(p521Uint1(x632)) + x600)
+	var x635 uint64
+	_, x635 = bits.Add64(x579, x615, uint64(0x0))
+	var x636 uint64
+	var x637 uint64
+	x636, x637 = bits.Add64(x581, x617, uint64(p521Uint1(x635)))
+	var x638 uint64
+	var x639 uint64
+	x638, x639 = bits.Add64(x583, x619, uint64(p521Uint1(x637)))
+	var x640 uint64
+	var x641 uint64
+	x640, x641 = bits.Add64(x585, x621, uint64(p521Uint1(x639)))
+	var x642 uint64
+	var x643 uint64
+	x642, x643 = bits.Add64(x587, x623, uint64(p521Uint1(x641)))
+	var x644 uint64
+	var x645 uint64
+	x644, x645 = bits.Add64(x589, x625, uint64(p521Uint1(x643)))
+	var x646 uint64
+	var x647 uint64
+	x646, x647 = bits.Add64(x591, x627, uint64(p521Uint1(x645)))
+	var x648 uint64
+	var x649 uint64
+	x648, x649 = bits.Add64(x593, x629, uint64(p521Uint1(x647)))
+	var x650 uint64
+	var x651 uint64
+	x650, x651 = bits.Add64(x595, x631, uint64(p521Uint1(x649)))
+	var x652 uint64
+	var x653 uint64
+	x652, x653 = bits.Add64(x597, x633, uint64(p521Uint1(x651)))
+	x654 := (uint64(p521Uint1(x653)) + uint64(p521Uint1(x598)))
+	var x655 uint64
+	var x656 uint64
+	x656, x655 = bits.Mul64(x6, arg2[8])
+	var x657 uint64
+	var x658 uint64
+	x658, x657 = bits.Mul64(x6, arg2[7])
+	var x659 uint64
+	var x660 uint64
+	x660, x659 = bits.Mul64(x6, arg2[6])
+	var x661 uint64
+	var x662 uint64
+	x662, x661 = bits.Mul64(x6, arg2[5])
+	var x663 uint64
+	var x664 uint64
+	x664, x663 = bits.Mul64(x6, arg2[4])
+	var x665 uint64
+	var x666 uint64
+	x666, x665 = bits.Mul64(x6, arg2[3])
+	var x667 uint64
+	var x668 uint64
+	x668, x667 = bits.Mul64(x6, arg2[2])
+	var x669 uint64
+	var x670 uint64
+	x670, x669 = bits.Mul64(x6, arg2[1])
+	var x671 uint64
+	var x672 uint64
+	x672, x671 = bits.Mul64(x6, arg2[0])
+	var x673 uint64
+	var x674 uint64
+	x673, x674 = bits.Add64(x672, x669, uint64(0x0))
+	var x675 uint64
+	var x676 uint64
+	x675, x676 = bits.Add64(x670, x667, uint64(p521Uint1(x674)))
+	var x677 uint64
+	var x678 uint64
+	x677, x678 = bits.Add64(x668, x665, uint64(p521Uint1(x676)))
+	var x679 uint64
+	var x680 uint64
+	x679, x680 = bits.Add64(x666, x663, uint64(p521Uint1(x678)))
+	var x681 uint64
+	var x682 uint64
+	x681, x682 = bits.Add64(x664, x661, uint64(p521Uint1(x680)))
+	var x683 uint64
+	var x684 uint64
+	x683, x684 = bits.Add64(x662, x659, uint64(p521Uint1(x682)))
+	var x685 uint64
+	var x686 uint64
+	x685, x686 = bits.Add64(x660, x657, uint64(p521Uint1(x684)))
+	var x687 uint64
+	var x688 uint64
+	x687, x688 = bits.Add64(x658, x655, uint64(p521Uint1(x686)))
+	x689 := (uint64(p521Uint1(x688)) + x656)
+	var x690 uint64
+	var x691 uint64
+	x690, x691 = bits.Add64(x636, x671, uint64(0x0))
+	var x692 uint64
+	var x693 uint64
+	x692, x693 = bits.Add64(x638, x673, uint64(p521Uint1(x691)))
+	var x694 uint64
+	var x695 uint64
+	x694, x695 = bits.Add64(x640, x675, uint64(p521Uint1(x693)))
+	var x696 uint64
+	var x697 uint64
+	x696, x697 = bits.Add64(x642, x677, uint64(p521Uint1(x695)))
+	var x698 uint64
+	var x699 uint64
+	x698, x699 = bits.Add64(x644, x679, uint64(p521Uint1(x697)))
+	var x700 uint64
+	var x701 uint64
+	x700, x701 = bits.Add64(x646, x681, uint64(p521Uint1(x699)))
+	var x702 uint64
+	var x703 uint64
+	x702, x703 = bits.Add64(x648, x683, uint64(p521Uint1(x701)))
+	var x704 uint64
+	var x705 uint64
+	x704, x705 = bits.Add64(x650, x685, uint64(p521Uint1(x703)))
+	var x706 uint64
+	var x707 uint64
+	x706, x707 = bits.Add64(x652, x687, uint64(p521Uint1(x705)))
+	var x708 uint64
+	var x709 uint64
+	x708, x709 = bits.Add64(x654, x689, uint64(p521Uint1(x707)))
+	var x710 uint64
+	var x711 uint64
+	x711, x710 = bits.Mul64(x690, 0x1ff)
+	var x712 uint64
+	var x713 uint64
+	x713, x712 = bits.Mul64(x690, 0xffffffffffffffff)
+	var x714 uint64
+	var x715 uint64
+	x715, x714 = bits.Mul64(x690, 0xffffffffffffffff)
+	var x716 uint64
+	var x717 uint64
+	x717, x716 = bits.Mul64(x690, 0xffffffffffffffff)
+	var x718 uint64
+	var x719 uint64
+	x719, x718 = bits.Mul64(x690, 0xffffffffffffffff)
+	var x720 uint64
+	var x721 uint64
+	x721, x720 = bits.Mul64(x690, 0xffffffffffffffff)
+	var x722 uint64
+	var x723 uint64
+	x723, x722 = bits.Mul64(x690, 0xffffffffffffffff)
+	var x724 uint64
+	var x725 uint64
+	x725, x724 = bits.Mul64(x690, 0xffffffffffffffff)
+	var x726 uint64
+	var x727 uint64
+	x727, x726 = bits.Mul64(x690, 0xffffffffffffffff)
+	var x728 uint64
+	var x729 uint64
+	x728, x729 = bits.Add64(x727, x724, uint64(0x0))
+	var x730 uint64
+	var x731 uint64
+	x730, x731 = bits.Add64(x725, x722, uint64(p521Uint1(x729)))
+	var x732 uint64
+	var x733 uint64
+	x732, x733 = bits.Add64(x723, x720, uint64(p521Uint1(x731)))
+	var x734 uint64
+	var x735 uint64
+	x734, x735 = bits.Add64(x721, x718, uint64(p521Uint1(x733)))
+	var x736 uint64
+	var x737 uint64
+	x736, x737 = bits.Add64(x719, x716, uint64(p521Uint1(x735)))
+	var x738 uint64
+	var x739 uint64
+	x738, x739 = bits.Add64(x717, x714, uint64(p521Uint1(x737)))
+	var x740 uint64
+	var x741 uint64
+	x740, x741 = bits.Add64(x715, x712, uint64(p521Uint1(x739)))
+	var x742 uint64
+	var x743 uint64
+	x742, x743 = bits.Add64(x713, x710, uint64(p521Uint1(x741)))
+	x744 := (uint64(p521Uint1(x743)) + x711)
+	var x746 uint64
+	_, x746 = bits.Add64(x690, x726, uint64(0x0))
+	var x747 uint64
+	var x748 uint64
+	x747, x748 = bits.Add64(x692, x728, uint64(p521Uint1(x746)))
+	var x749 uint64
+	var x750 uint64
+	x749, x750 = bits.Add64(x694, x730, uint64(p521Uint1(x748)))
+	var x751 uint64
+	var x752 uint64
+	x751, x752 = bits.Add64(x696, x732, uint64(p521Uint1(x750)))
+	var x753 uint64
+	var x754 uint64
+	x753, x754 = bits.Add64(x698, x734, uint64(p521Uint1(x752)))
+	var x755 uint64
+	var x756 uint64
+	x755, x756 = bits.Add64(x700, x736, uint64(p521Uint1(x754)))
+	var x757 uint64
+	var x758 uint64
+	x757, x758 = bits.Add64(x702, x738, uint64(p521Uint1(x756)))
+	var x759 uint64
+	var x760 uint64
+	x759, x760 = bits.Add64(x704, x740, uint64(p521Uint1(x758)))
+	var x761 uint64
+	var x762 uint64
+	x761, x762 = bits.Add64(x706, x742, uint64(p521Uint1(x760)))
+	var x763 uint64
+	var x764 uint64
+	x763, x764 = bits.Add64(x708, x744, uint64(p521Uint1(x762)))
+	x765 := (uint64(p521Uint1(x764)) + uint64(p521Uint1(x709)))
+	var x766 uint64
+	var x767 uint64
+	x767, x766 = bits.Mul64(x7, arg2[8])
+	var x768 uint64
+	var x769 uint64
+	x769, x768 = bits.Mul64(x7, arg2[7])
+	var x770 uint64
+	var x771 uint64
+	x771, x770 = bits.Mul64(x7, arg2[6])
+	var x772 uint64
+	var x773 uint64
+	x773, x772 = bits.Mul64(x7, arg2[5])
+	var x774 uint64
+	var x775 uint64
+	x775, x774 = bits.Mul64(x7, arg2[4])
+	var x776 uint64
+	var x777 uint64
+	x777, x776 = bits.Mul64(x7, arg2[3])
+	var x778 uint64
+	var x779 uint64
+	x779, x778 = bits.Mul64(x7, arg2[2])
+	var x780 uint64
+	var x781 uint64
+	x781, x780 = bits.Mul64(x7, arg2[1])
+	var x782 uint64
+	var x783 uint64
+	x783, x782 = bits.Mul64(x7, arg2[0])
+	var x784 uint64
+	var x785 uint64
+	x784, x785 = bits.Add64(x783, x780, uint64(0x0))
+	var x786 uint64
+	var x787 uint64
+	x786, x787 = bits.Add64(x781, x778, uint64(p521Uint1(x785)))
+	var x788 uint64
+	var x789 uint64
+	x788, x789 = bits.Add64(x779, x776, uint64(p521Uint1(x787)))
+	var x790 uint64
+	var x791 uint64
+	x790, x791 = bits.Add64(x777, x774, uint64(p521Uint1(x789)))
+	var x792 uint64
+	var x793 uint64
+	x792, x793 = bits.Add64(x775, x772, uint64(p521Uint1(x791)))
+	var x794 uint64
+	var x795 uint64
+	x794, x795 = bits.Add64(x773, x770, uint64(p521Uint1(x793)))
+	var x796 uint64
+	var x797 uint64
+	x796, x797 = bits.Add64(x771, x768, uint64(p521Uint1(x795)))
+	var x798 uint64
+	var x799 uint64
+	x798, x799 = bits.Add64(x769, x766, uint64(p521Uint1(x797)))
+	x800 := (uint64(p521Uint1(x799)) + x767)
+	var x801 uint64
+	var x802 uint64
+	x801, x802 = bits.Add64(x747, x782, uint64(0x0))
+	var x803 uint64
+	var x804 uint64
+	x803, x804 = bits.Add64(x749, x784, uint64(p521Uint1(x802)))
+	var x805 uint64
+	var x806 uint64
+	x805, x806 = bits.Add64(x751, x786, uint64(p521Uint1(x804)))
+	var x807 uint64
+	var x808 uint64
+	x807, x808 = bits.Add64(x753, x788, uint64(p521Uint1(x806)))
+	var x809 uint64
+	var x810 uint64
+	x809, x810 = bits.Add64(x755, x790, uint64(p521Uint1(x808)))
+	var x811 uint64
+	var x812 uint64
+	x811, x812 = bits.Add64(x757, x792, uint64(p521Uint1(x810)))
+	var x813 uint64
+	var x814 uint64
+	x813, x814 = bits.Add64(x759, x794, uint64(p521Uint1(x812)))
+	var x815 uint64
+	var x816 uint64
+	x815, x816 = bits.Add64(x761, x796, uint64(p521Uint1(x814)))
+	var x817 uint64
+	var x818 uint64
+	x817, x818 = bits.Add64(x763, x798, uint64(p521Uint1(x816)))
+	var x819 uint64
+	var x820 uint64
+	x819, x820 = bits.Add64(x765, x800, uint64(p521Uint1(x818)))
+	var x821 uint64
+	var x822 uint64
+	x822, x821 = bits.Mul64(x801, 0x1ff)
+	var x823 uint64
+	var x824 uint64
+	x824, x823 = bits.Mul64(x801, 0xffffffffffffffff)
+	var x825 uint64
+	var x826 uint64
+	x826, x825 = bits.Mul64(x801, 0xffffffffffffffff)
+	var x827 uint64
+	var x828 uint64
+	x828, x827 = bits.Mul64(x801, 0xffffffffffffffff)
+	var x829 uint64
+	var x830 uint64
+	x830, x829 = bits.Mul64(x801, 0xffffffffffffffff)
+	var x831 uint64
+	var x832 uint64
+	x832, x831 = bits.Mul64(x801, 0xffffffffffffffff)
+	var x833 uint64
+	var x834 uint64
+	x834, x833 = bits.Mul64(x801, 0xffffffffffffffff)
+	var x835 uint64
+	var x836 uint64
+	x836, x835 = bits.Mul64(x801, 0xffffffffffffffff)
+	var x837 uint64
+	var x838 uint64
+	x838, x837 = bits.Mul64(x801, 0xffffffffffffffff)
+	var x839 uint64
+	var x840 uint64
+	x839, x840 = bits.Add64(x838, x835, uint64(0x0))
+	var x841 uint64
+	var x842 uint64
+	x841, x842 = bits.Add64(x836, x833, uint64(p521Uint1(x840)))
+	var x843 uint64
+	var x844 uint64
+	x843, x844 = bits.Add64(x834, x831, uint64(p521Uint1(x842)))
+	var x845 uint64
+	var x846 uint64
+	x845, x846 = bits.Add64(x832, x829, uint64(p521Uint1(x844)))
+	var x847 uint64
+	var x848 uint64
+	x847, x848 = bits.Add64(x830, x827, uint64(p521Uint1(x846)))
+	var x849 uint64
+	var x850 uint64
+	x849, x850 = bits.Add64(x828, x825, uint64(p521Uint1(x848)))
+	var x851 uint64
+	var x852 uint64
+	x851, x852 = bits.Add64(x826, x823, uint64(p521Uint1(x850)))
+	var x853 uint64
+	var x854 uint64
+	x853, x854 = bits.Add64(x824, x821, uint64(p521Uint1(x852)))
+	x855 := (uint64(p521Uint1(x854)) + x822)
+	var x857 uint64
+	_, x857 = bits.Add64(x801, x837, uint64(0x0))
+	var x858 uint64
+	var x859 uint64
+	x858, x859 = bits.Add64(x803, x839, uint64(p521Uint1(x857)))
+	var x860 uint64
+	var x861 uint64
+	x860, x861 = bits.Add64(x805, x841, uint64(p521Uint1(x859)))
+	var x862 uint64
+	var x863 uint64
+	x862, x863 = bits.Add64(x807, x843, uint64(p521Uint1(x861)))
+	var x864 uint64
+	var x865 uint64
+	x864, x865 = bits.Add64(x809, x845, uint64(p521Uint1(x863)))
+	var x866 uint64
+	var x867 uint64
+	x866, x867 = bits.Add64(x811, x847, uint64(p521Uint1(x865)))
+	var x868 uint64
+	var x869 uint64
+	x868, x869 = bits.Add64(x813, x849, uint64(p521Uint1(x867)))
+	var x870 uint64
+	var x871 uint64
+	x870, x871 = bits.Add64(x815, x851, uint64(p521Uint1(x869)))
+	var x872 uint64
+	var x873 uint64
+	x872, x873 = bits.Add64(x817, x853, uint64(p521Uint1(x871)))
+	var x874 uint64
+	var x875 uint64
+	x874, x875 = bits.Add64(x819, x855, uint64(p521Uint1(x873)))
+	x876 := (uint64(p521Uint1(x875)) + uint64(p521Uint1(x820)))
+	var x877 uint64
+	var x878 uint64
+	x878, x877 = bits.Mul64(x8, arg2[8])
+	var x879 uint64
+	var x880 uint64
+	x880, x879 = bits.Mul64(x8, arg2[7])
+	var x881 uint64
+	var x882 uint64
+	x882, x881 = bits.Mul64(x8, arg2[6])
+	var x883 uint64
+	var x884 uint64
+	x884, x883 = bits.Mul64(x8, arg2[5])
+	var x885 uint64
+	var x886 uint64
+	x886, x885 = bits.Mul64(x8, arg2[4])
+	var x887 uint64
+	var x888 uint64
+	x888, x887 = bits.Mul64(x8, arg2[3])
+	var x889 uint64
+	var x890 uint64
+	x890, x889 = bits.Mul64(x8, arg2[2])
+	var x891 uint64
+	var x892 uint64
+	x892, x891 = bits.Mul64(x8, arg2[1])
+	var x893 uint64
+	var x894 uint64
+	x894, x893 = bits.Mul64(x8, arg2[0])
+	var x895 uint64
+	var x896 uint64
+	x895, x896 = bits.Add64(x894, x891, uint64(0x0))
+	var x897 uint64
+	var x898 uint64
+	x897, x898 = bits.Add64(x892, x889, uint64(p521Uint1(x896)))
+	var x899 uint64
+	var x900 uint64
+	x899, x900 = bits.Add64(x890, x887, uint64(p521Uint1(x898)))
+	var x901 uint64
+	var x902 uint64
+	x901, x902 = bits.Add64(x888, x885, uint64(p521Uint1(x900)))
+	var x903 uint64
+	var x904 uint64
+	x903, x904 = bits.Add64(x886, x883, uint64(p521Uint1(x902)))
+	var x905 uint64
+	var x906 uint64
+	x905, x906 = bits.Add64(x884, x881, uint64(p521Uint1(x904)))
+	var x907 uint64
+	var x908 uint64
+	x907, x908 = bits.Add64(x882, x879, uint64(p521Uint1(x906)))
+	var x909 uint64
+	var x910 uint64
+	x909, x910 = bits.Add64(x880, x877, uint64(p521Uint1(x908)))
+	x911 := (uint64(p521Uint1(x910)) + x878)
+	var x912 uint64
+	var x913 uint64
+	x912, x913 = bits.Add64(x858, x893, uint64(0x0))
+	var x914 uint64
+	var x915 uint64
+	x914, x915 = bits.Add64(x860, x895, uint64(p521Uint1(x913)))
+	var x916 uint64
+	var x917 uint64
+	x916, x917 = bits.Add64(x862, x897, uint64(p521Uint1(x915)))
+	var x918 uint64
+	var x919 uint64
+	x918, x919 = bits.Add64(x864, x899, uint64(p521Uint1(x917)))
+	var x920 uint64
+	var x921 uint64
+	x920, x921 = bits.Add64(x866, x901, uint64(p521Uint1(x919)))
+	var x922 uint64
+	var x923 uint64
+	x922, x923 = bits.Add64(x868, x903, uint64(p521Uint1(x921)))
+	var x924 uint64
+	var x925 uint64
+	x924, x925 = bits.Add64(x870, x905, uint64(p521Uint1(x923)))
+	var x926 uint64
+	var x927 uint64
+	x926, x927 = bits.Add64(x872, x907, uint64(p521Uint1(x925)))
+	var x928 uint64
+	var x929 uint64
+	x928, x929 = bits.Add64(x874, x909, uint64(p521Uint1(x927)))
+	var x930 uint64
+	var x931 uint64
+	x930, x931 = bits.Add64(x876, x911, uint64(p521Uint1(x929)))
+	var x932 uint64
+	var x933 uint64
+	x933, x932 = bits.Mul64(x912, 0x1ff)
+	var x934 uint64
+	var x935 uint64
+	x935, x934 = bits.Mul64(x912, 0xffffffffffffffff)
+	var x936 uint64
+	var x937 uint64
+	x937, x936 = bits.Mul64(x912, 0xffffffffffffffff)
+	var x938 uint64
+	var x939 uint64
+	x939, x938 = bits.Mul64(x912, 0xffffffffffffffff)
+	var x940 uint64
+	var x941 uint64
+	x941, x940 = bits.Mul64(x912, 0xffffffffffffffff)
+	var x942 uint64
+	var x943 uint64
+	x943, x942 = bits.Mul64(x912, 0xffffffffffffffff)
+	var x944 uint64
+	var x945 uint64
+	x945, x944 = bits.Mul64(x912, 0xffffffffffffffff)
+	var x946 uint64
+	var x947 uint64
+	x947, x946 = bits.Mul64(x912, 0xffffffffffffffff)
+	var x948 uint64
+	var x949 uint64
+	x949, x948 = bits.Mul64(x912, 0xffffffffffffffff)
+	var x950 uint64
+	var x951 uint64
+	x950, x951 = bits.Add64(x949, x946, uint64(0x0))
+	var x952 uint64
+	var x953 uint64
+	x952, x953 = bits.Add64(x947, x944, uint64(p521Uint1(x951)))
+	var x954 uint64
+	var x955 uint64
+	x954, x955 = bits.Add64(x945, x942, uint64(p521Uint1(x953)))
+	var x956 uint64
+	var x957 uint64
+	x956, x957 = bits.Add64(x943, x940, uint64(p521Uint1(x955)))
+	var x958 uint64
+	var x959 uint64
+	x958, x959 = bits.Add64(x941, x938, uint64(p521Uint1(x957)))
+	var x960 uint64
+	var x961 uint64
+	x960, x961 = bits.Add64(x939, x936, uint64(p521Uint1(x959)))
+	var x962 uint64
+	var x963 uint64
+	x962, x963 = bits.Add64(x937, x934, uint64(p521Uint1(x961)))
+	var x964 uint64
+	var x965 uint64
+	x964, x965 = bits.Add64(x935, x932, uint64(p521Uint1(x963)))
+	x966 := (uint64(p521Uint1(x965)) + x933)
+	var x968 uint64
+	_, x968 = bits.Add64(x912, x948, uint64(0x0))
+	var x969 uint64
+	var x970 uint64
+	x969, x970 = bits.Add64(x914, x950, uint64(p521Uint1(x968)))
+	var x971 uint64
+	var x972 uint64
+	x971, x972 = bits.Add64(x916, x952, uint64(p521Uint1(x970)))
+	var x973 uint64
+	var x974 uint64
+	x973, x974 = bits.Add64(x918, x954, uint64(p521Uint1(x972)))
+	var x975 uint64
+	var x976 uint64
+	x975, x976 = bits.Add64(x920, x956, uint64(p521Uint1(x974)))
+	var x977 uint64
+	var x978 uint64
+	x977, x978 = bits.Add64(x922, x958, uint64(p521Uint1(x976)))
+	var x979 uint64
+	var x980 uint64
+	x979, x980 = bits.Add64(x924, x960, uint64(p521Uint1(x978)))
+	var x981 uint64
+	var x982 uint64
+	x981, x982 = bits.Add64(x926, x962, uint64(p521Uint1(x980)))
+	var x983 uint64
+	var x984 uint64
+	x983, x984 = bits.Add64(x928, x964, uint64(p521Uint1(x982)))
+	var x985 uint64
+	var x986 uint64
+	x985, x986 = bits.Add64(x930, x966, uint64(p521Uint1(x984)))
+	x987 := (uint64(p521Uint1(x986)) + uint64(p521Uint1(x931)))
+	var x988 uint64
+	var x989 uint64
+	x988, x989 = bits.Sub64(x969, 0xffffffffffffffff, uint64(0x0))
+	var x990 uint64
+	var x991 uint64
+	x990, x991 = bits.Sub64(x971, 0xffffffffffffffff, uint64(p521Uint1(x989)))
+	var x992 uint64
+	var x993 uint64
+	x992, x993 = bits.Sub64(x973, 0xffffffffffffffff, uint64(p521Uint1(x991)))
+	var x994 uint64
+	var x995 uint64
+	x994, x995 = bits.Sub64(x975, 0xffffffffffffffff, uint64(p521Uint1(x993)))
+	var x996 uint64
+	var x997 uint64
+	x996, x997 = bits.Sub64(x977, 0xffffffffffffffff, uint64(p521Uint1(x995)))
+	var x998 uint64
+	var x999 uint64
+	x998, x999 = bits.Sub64(x979, 0xffffffffffffffff, uint64(p521Uint1(x997)))
+	var x1000 uint64
+	var x1001 uint64
+	x1000, x1001 = bits.Sub64(x981, 0xffffffffffffffff, uint64(p521Uint1(x999)))
+	var x1002 uint64
+	var x1003 uint64
+	x1002, x1003 = bits.Sub64(x983, 0xffffffffffffffff, uint64(p521Uint1(x1001)))
+	var x1004 uint64
+	var x1005 uint64
+	x1004, x1005 = bits.Sub64(x985, 0x1ff, uint64(p521Uint1(x1003)))
+	var x1007 uint64
+	_, x1007 = bits.Sub64(x987, uint64(0x0), uint64(p521Uint1(x1005)))
+	var x1008 uint64
+	p521CmovznzU64(&x1008, p521Uint1(x1007), x988, x969)
+	var x1009 uint64
+	p521CmovznzU64(&x1009, p521Uint1(x1007), x990, x971)
+	var x1010 uint64
+	p521CmovznzU64(&x1010, p521Uint1(x1007), x992, x973)
+	var x1011 uint64
+	p521CmovznzU64(&x1011, p521Uint1(x1007), x994, x975)
+	var x1012 uint64
+	p521CmovznzU64(&x1012, p521Uint1(x1007), x996, x977)
+	var x1013 uint64
+	p521CmovznzU64(&x1013, p521Uint1(x1007), x998, x979)
+	var x1014 uint64
+	p521CmovznzU64(&x1014, p521Uint1(x1007), x1000, x981)
+	var x1015 uint64
+	p521CmovznzU64(&x1015, p521Uint1(x1007), x1002, x983)
+	var x1016 uint64
+	p521CmovznzU64(&x1016, p521Uint1(x1007), x1004, x985)
+	out1[0] = x1008
+	out1[1] = x1009
+	out1[2] = x1010
+	out1[3] = x1011
+	out1[4] = x1012
+	out1[5] = x1013
+	out1[6] = x1014
+	out1[7] = x1015
+	out1[8] = x1016
+}
+
+// p521Square squares a field element in the Montgomery domain.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//
+// Postconditions:
+//
+//	eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) * eval (from_montgomery arg1)) mod m
+//	0 ≤ eval out1 < m
+func p521Square(out1 *p521MontgomeryDomainFieldElement, arg1 *p521MontgomeryDomainFieldElement) {
+	x1 := arg1[1]
+	x2 := arg1[2]
+	x3 := arg1[3]
+	x4 := arg1[4]
+	x5 := arg1[5]
+	x6 := arg1[6]
+	x7 := arg1[7]
+	x8 := arg1[8]
+	x9 := arg1[0]
+	var x10 uint64
+	var x11 uint64
+	x11, x10 = bits.Mul64(x9, arg1[8])
+	var x12 uint64
+	var x13 uint64
+	x13, x12 = bits.Mul64(x9, arg1[7])
+	var x14 uint64
+	var x15 uint64
+	x15, x14 = bits.Mul64(x9, arg1[6])
+	var x16 uint64
+	var x17 uint64
+	x17, x16 = bits.Mul64(x9, arg1[5])
+	var x18 uint64
+	var x19 uint64
+	x19, x18 = bits.Mul64(x9, arg1[4])
+	var x20 uint64
+	var x21 uint64
+	x21, x20 = bits.Mul64(x9, arg1[3])
+	var x22 uint64
+	var x23 uint64
+	x23, x22 = bits.Mul64(x9, arg1[2])
+	var x24 uint64
+	var x25 uint64
+	x25, x24 = bits.Mul64(x9, arg1[1])
+	var x26 uint64
+	var x27 uint64
+	x27, x26 = bits.Mul64(x9, arg1[0])
+	var x28 uint64
+	var x29 uint64
+	x28, x29 = bits.Add64(x27, x24, uint64(0x0))
+	var x30 uint64
+	var x31 uint64
+	x30, x31 = bits.Add64(x25, x22, uint64(p521Uint1(x29)))
+	var x32 uint64
+	var x33 uint64
+	x32, x33 = bits.Add64(x23, x20, uint64(p521Uint1(x31)))
+	var x34 uint64
+	var x35 uint64
+	x34, x35 = bits.Add64(x21, x18, uint64(p521Uint1(x33)))
+	var x36 uint64
+	var x37 uint64
+	x36, x37 = bits.Add64(x19, x16, uint64(p521Uint1(x35)))
+	var x38 uint64
+	var x39 uint64
+	x38, x39 = bits.Add64(x17, x14, uint64(p521Uint1(x37)))
+	var x40 uint64
+	var x41 uint64
+	x40, x41 = bits.Add64(x15, x12, uint64(p521Uint1(x39)))
+	var x42 uint64
+	var x43 uint64
+	x42, x43 = bits.Add64(x13, x10, uint64(p521Uint1(x41)))
+	x44 := (uint64(p521Uint1(x43)) + x11)
+	var x45 uint64
+	var x46 uint64
+	x46, x45 = bits.Mul64(x26, 0x1ff)
+	var x47 uint64
+	var x48 uint64
+	x48, x47 = bits.Mul64(x26, 0xffffffffffffffff)
+	var x49 uint64
+	var x50 uint64
+	x50, x49 = bits.Mul64(x26, 0xffffffffffffffff)
+	var x51 uint64
+	var x52 uint64
+	x52, x51 = bits.Mul64(x26, 0xffffffffffffffff)
+	var x53 uint64
+	var x54 uint64
+	x54, x53 = bits.Mul64(x26, 0xffffffffffffffff)
+	var x55 uint64
+	var x56 uint64
+	x56, x55 = bits.Mul64(x26, 0xffffffffffffffff)
+	var x57 uint64
+	var x58 uint64
+	x58, x57 = bits.Mul64(x26, 0xffffffffffffffff)
+	var x59 uint64
+	var x60 uint64
+	x60, x59 = bits.Mul64(x26, 0xffffffffffffffff)
+	var x61 uint64
+	var x62 uint64
+	x62, x61 = bits.Mul64(x26, 0xffffffffffffffff)
+	var x63 uint64
+	var x64 uint64
+	x63, x64 = bits.Add64(x62, x59, uint64(0x0))
+	var x65 uint64
+	var x66 uint64
+	x65, x66 = bits.Add64(x60, x57, uint64(p521Uint1(x64)))
+	var x67 uint64
+	var x68 uint64
+	x67, x68 = bits.Add64(x58, x55, uint64(p521Uint1(x66)))
+	var x69 uint64
+	var x70 uint64
+	x69, x70 = bits.Add64(x56, x53, uint64(p521Uint1(x68)))
+	var x71 uint64
+	var x72 uint64
+	x71, x72 = bits.Add64(x54, x51, uint64(p521Uint1(x70)))
+	var x73 uint64
+	var x74 uint64
+	x73, x74 = bits.Add64(x52, x49, uint64(p521Uint1(x72)))
+	var x75 uint64
+	var x76 uint64
+	x75, x76 = bits.Add64(x50, x47, uint64(p521Uint1(x74)))
+	var x77 uint64
+	var x78 uint64
+	x77, x78 = bits.Add64(x48, x45, uint64(p521Uint1(x76)))
+	x79 := (uint64(p521Uint1(x78)) + x46)
+	var x81 uint64
+	_, x81 = bits.Add64(x26, x61, uint64(0x0))
+	var x82 uint64
+	var x83 uint64
+	x82, x83 = bits.Add64(x28, x63, uint64(p521Uint1(x81)))
+	var x84 uint64
+	var x85 uint64
+	x84, x85 = bits.Add64(x30, x65, uint64(p521Uint1(x83)))
+	var x86 uint64
+	var x87 uint64
+	x86, x87 = bits.Add64(x32, x67, uint64(p521Uint1(x85)))
+	var x88 uint64
+	var x89 uint64
+	x88, x89 = bits.Add64(x34, x69, uint64(p521Uint1(x87)))
+	var x90 uint64
+	var x91 uint64
+	x90, x91 = bits.Add64(x36, x71, uint64(p521Uint1(x89)))
+	var x92 uint64
+	var x93 uint64
+	x92, x93 = bits.Add64(x38, x73, uint64(p521Uint1(x91)))
+	var x94 uint64
+	var x95 uint64
+	x94, x95 = bits.Add64(x40, x75, uint64(p521Uint1(x93)))
+	var x96 uint64
+	var x97 uint64
+	x96, x97 = bits.Add64(x42, x77, uint64(p521Uint1(x95)))
+	var x98 uint64
+	var x99 uint64
+	x98, x99 = bits.Add64(x44, x79, uint64(p521Uint1(x97)))
+	var x100 uint64
+	var x101 uint64
+	x101, x100 = bits.Mul64(x1, arg1[8])
+	var x102 uint64
+	var x103 uint64
+	x103, x102 = bits.Mul64(x1, arg1[7])
+	var x104 uint64
+	var x105 uint64
+	x105, x104 = bits.Mul64(x1, arg1[6])
+	var x106 uint64
+	var x107 uint64
+	x107, x106 = bits.Mul64(x1, arg1[5])
+	var x108 uint64
+	var x109 uint64
+	x109, x108 = bits.Mul64(x1, arg1[4])
+	var x110 uint64
+	var x111 uint64
+	x111, x110 = bits.Mul64(x1, arg1[3])
+	var x112 uint64
+	var x113 uint64
+	x113, x112 = bits.Mul64(x1, arg1[2])
+	var x114 uint64
+	var x115 uint64
+	x115, x114 = bits.Mul64(x1, arg1[1])
+	var x116 uint64
+	var x117 uint64
+	x117, x116 = bits.Mul64(x1, arg1[0])
+	var x118 uint64
+	var x119 uint64
+	x118, x119 = bits.Add64(x117, x114, uint64(0x0))
+	var x120 uint64
+	var x121 uint64
+	x120, x121 = bits.Add64(x115, x112, uint64(p521Uint1(x119)))
+	var x122 uint64
+	var x123 uint64
+	x122, x123 = bits.Add64(x113, x110, uint64(p521Uint1(x121)))
+	var x124 uint64
+	var x125 uint64
+	x124, x125 = bits.Add64(x111, x108, uint64(p521Uint1(x123)))
+	var x126 uint64
+	var x127 uint64
+	x126, x127 = bits.Add64(x109, x106, uint64(p521Uint1(x125)))
+	var x128 uint64
+	var x129 uint64
+	x128, x129 = bits.Add64(x107, x104, uint64(p521Uint1(x127)))
+	var x130 uint64
+	var x131 uint64
+	x130, x131 = bits.Add64(x105, x102, uint64(p521Uint1(x129)))
+	var x132 uint64
+	var x133 uint64
+	x132, x133 = bits.Add64(x103, x100, uint64(p521Uint1(x131)))
+	x134 := (uint64(p521Uint1(x133)) + x101)
+	var x135 uint64
+	var x136 uint64
+	x135, x136 = bits.Add64(x82, x116, uint64(0x0))
+	var x137 uint64
+	var x138 uint64
+	x137, x138 = bits.Add64(x84, x118, uint64(p521Uint1(x136)))
+	var x139 uint64
+	var x140 uint64
+	x139, x140 = bits.Add64(x86, x120, uint64(p521Uint1(x138)))
+	var x141 uint64
+	var x142 uint64
+	x141, x142 = bits.Add64(x88, x122, uint64(p521Uint1(x140)))
+	var x143 uint64
+	var x144 uint64
+	x143, x144 = bits.Add64(x90, x124, uint64(p521Uint1(x142)))
+	var x145 uint64
+	var x146 uint64
+	x145, x146 = bits.Add64(x92, x126, uint64(p521Uint1(x144)))
+	var x147 uint64
+	var x148 uint64
+	x147, x148 = bits.Add64(x94, x128, uint64(p521Uint1(x146)))
+	var x149 uint64
+	var x150 uint64
+	x149, x150 = bits.Add64(x96, x130, uint64(p521Uint1(x148)))
+	var x151 uint64
+	var x152 uint64
+	x151, x152 = bits.Add64(x98, x132, uint64(p521Uint1(x150)))
+	var x153 uint64
+	var x154 uint64
+	x153, x154 = bits.Add64(uint64(p521Uint1(x99)), x134, uint64(p521Uint1(x152)))
+	var x155 uint64
+	var x156 uint64
+	x156, x155 = bits.Mul64(x135, 0x1ff)
+	var x157 uint64
+	var x158 uint64
+	x158, x157 = bits.Mul64(x135, 0xffffffffffffffff)
+	var x159 uint64
+	var x160 uint64
+	x160, x159 = bits.Mul64(x135, 0xffffffffffffffff)
+	var x161 uint64
+	var x162 uint64
+	x162, x161 = bits.Mul64(x135, 0xffffffffffffffff)
+	var x163 uint64
+	var x164 uint64
+	x164, x163 = bits.Mul64(x135, 0xffffffffffffffff)
+	var x165 uint64
+	var x166 uint64
+	x166, x165 = bits.Mul64(x135, 0xffffffffffffffff)
+	var x167 uint64
+	var x168 uint64
+	x168, x167 = bits.Mul64(x135, 0xffffffffffffffff)
+	var x169 uint64
+	var x170 uint64
+	x170, x169 = bits.Mul64(x135, 0xffffffffffffffff)
+	var x171 uint64
+	var x172 uint64
+	x172, x171 = bits.Mul64(x135, 0xffffffffffffffff)
+	var x173 uint64
+	var x174 uint64
+	x173, x174 = bits.Add64(x172, x169, uint64(0x0))
+	var x175 uint64
+	var x176 uint64
+	x175, x176 = bits.Add64(x170, x167, uint64(p521Uint1(x174)))
+	var x177 uint64
+	var x178 uint64
+	x177, x178 = bits.Add64(x168, x165, uint64(p521Uint1(x176)))
+	var x179 uint64
+	var x180 uint64
+	x179, x180 = bits.Add64(x166, x163, uint64(p521Uint1(x178)))
+	var x181 uint64
+	var x182 uint64
+	x181, x182 = bits.Add64(x164, x161, uint64(p521Uint1(x180)))
+	var x183 uint64
+	var x184 uint64
+	x183, x184 = bits.Add64(x162, x159, uint64(p521Uint1(x182)))
+	var x185 uint64
+	var x186 uint64
+	x185, x186 = bits.Add64(x160, x157, uint64(p521Uint1(x184)))
+	var x187 uint64
+	var x188 uint64
+	x187, x188 = bits.Add64(x158, x155, uint64(p521Uint1(x186)))
+	x189 := (uint64(p521Uint1(x188)) + x156)
+	var x191 uint64
+	_, x191 = bits.Add64(x135, x171, uint64(0x0))
+	var x192 uint64
+	var x193 uint64
+	x192, x193 = bits.Add64(x137, x173, uint64(p521Uint1(x191)))
+	var x194 uint64
+	var x195 uint64
+	x194, x195 = bits.Add64(x139, x175, uint64(p521Uint1(x193)))
+	var x196 uint64
+	var x197 uint64
+	x196, x197 = bits.Add64(x141, x177, uint64(p521Uint1(x195)))
+	var x198 uint64
+	var x199 uint64
+	x198, x199 = bits.Add64(x143, x179, uint64(p521Uint1(x197)))
+	var x200 uint64
+	var x201 uint64
+	x200, x201 = bits.Add64(x145, x181, uint64(p521Uint1(x199)))
+	var x202 uint64
+	var x203 uint64
+	x202, x203 = bits.Add64(x147, x183, uint64(p521Uint1(x201)))
+	var x204 uint64
+	var x205 uint64
+	x204, x205 = bits.Add64(x149, x185, uint64(p521Uint1(x203)))
+	var x206 uint64
+	var x207 uint64
+	x206, x207 = bits.Add64(x151, x187, uint64(p521Uint1(x205)))
+	var x208 uint64
+	var x209 uint64
+	x208, x209 = bits.Add64(x153, x189, uint64(p521Uint1(x207)))
+	x210 := (uint64(p521Uint1(x209)) + uint64(p521Uint1(x154)))
+	var x211 uint64
+	var x212 uint64
+	x212, x211 = bits.Mul64(x2, arg1[8])
+	var x213 uint64
+	var x214 uint64
+	x214, x213 = bits.Mul64(x2, arg1[7])
+	var x215 uint64
+	var x216 uint64
+	x216, x215 = bits.Mul64(x2, arg1[6])
+	var x217 uint64
+	var x218 uint64
+	x218, x217 = bits.Mul64(x2, arg1[5])
+	var x219 uint64
+	var x220 uint64
+	x220, x219 = bits.Mul64(x2, arg1[4])
+	var x221 uint64
+	var x222 uint64
+	x222, x221 = bits.Mul64(x2, arg1[3])
+	var x223 uint64
+	var x224 uint64
+	x224, x223 = bits.Mul64(x2, arg1[2])
+	var x225 uint64
+	var x226 uint64
+	x226, x225 = bits.Mul64(x2, arg1[1])
+	var x227 uint64
+	var x228 uint64
+	x228, x227 = bits.Mul64(x2, arg1[0])
+	var x229 uint64
+	var x230 uint64
+	x229, x230 = bits.Add64(x228, x225, uint64(0x0))
+	var x231 uint64
+	var x232 uint64
+	x231, x232 = bits.Add64(x226, x223, uint64(p521Uint1(x230)))
+	var x233 uint64
+	var x234 uint64
+	x233, x234 = bits.Add64(x224, x221, uint64(p521Uint1(x232)))
+	var x235 uint64
+	var x236 uint64
+	x235, x236 = bits.Add64(x222, x219, uint64(p521Uint1(x234)))
+	var x237 uint64
+	var x238 uint64
+	x237, x238 = bits.Add64(x220, x217, uint64(p521Uint1(x236)))
+	var x239 uint64
+	var x240 uint64
+	x239, x240 = bits.Add64(x218, x215, uint64(p521Uint1(x238)))
+	var x241 uint64
+	var x242 uint64
+	x241, x242 = bits.Add64(x216, x213, uint64(p521Uint1(x240)))
+	var x243 uint64
+	var x244 uint64
+	x243, x244 = bits.Add64(x214, x211, uint64(p521Uint1(x242)))
+	x245 := (uint64(p521Uint1(x244)) + x212)
+	var x246 uint64
+	var x247 uint64
+	x246, x247 = bits.Add64(x192, x227, uint64(0x0))
+	var x248 uint64
+	var x249 uint64
+	x248, x249 = bits.Add64(x194, x229, uint64(p521Uint1(x247)))
+	var x250 uint64
+	var x251 uint64
+	x250, x251 = bits.Add64(x196, x231, uint64(p521Uint1(x249)))
+	var x252 uint64
+	var x253 uint64
+	x252, x253 = bits.Add64(x198, x233, uint64(p521Uint1(x251)))
+	var x254 uint64
+	var x255 uint64
+	x254, x255 = bits.Add64(x200, x235, uint64(p521Uint1(x253)))
+	var x256 uint64
+	var x257 uint64
+	x256, x257 = bits.Add64(x202, x237, uint64(p521Uint1(x255)))
+	var x258 uint64
+	var x259 uint64
+	x258, x259 = bits.Add64(x204, x239, uint64(p521Uint1(x257)))
+	var x260 uint64
+	var x261 uint64
+	x260, x261 = bits.Add64(x206, x241, uint64(p521Uint1(x259)))
+	var x262 uint64
+	var x263 uint64
+	x262, x263 = bits.Add64(x208, x243, uint64(p521Uint1(x261)))
+	var x264 uint64
+	var x265 uint64
+	x264, x265 = bits.Add64(x210, x245, uint64(p521Uint1(x263)))
+	var x266 uint64
+	var x267 uint64
+	x267, x266 = bits.Mul64(x246, 0x1ff)
+	var x268 uint64
+	var x269 uint64
+	x269, x268 = bits.Mul64(x246, 0xffffffffffffffff)
+	var x270 uint64
+	var x271 uint64
+	x271, x270 = bits.Mul64(x246, 0xffffffffffffffff)
+	var x272 uint64
+	var x273 uint64
+	x273, x272 = bits.Mul64(x246, 0xffffffffffffffff)
+	var x274 uint64
+	var x275 uint64
+	x275, x274 = bits.Mul64(x246, 0xffffffffffffffff)
+	var x276 uint64
+	var x277 uint64
+	x277, x276 = bits.Mul64(x246, 0xffffffffffffffff)
+	var x278 uint64
+	var x279 uint64
+	x279, x278 = bits.Mul64(x246, 0xffffffffffffffff)
+	var x280 uint64
+	var x281 uint64
+	x281, x280 = bits.Mul64(x246, 0xffffffffffffffff)
+	var x282 uint64
+	var x283 uint64
+	x283, x282 = bits.Mul64(x246, 0xffffffffffffffff)
+	var x284 uint64
+	var x285 uint64
+	x284, x285 = bits.Add64(x283, x280, uint64(0x0))
+	var x286 uint64
+	var x287 uint64
+	x286, x287 = bits.Add64(x281, x278, uint64(p521Uint1(x285)))
+	var x288 uint64
+	var x289 uint64
+	x288, x289 = bits.Add64(x279, x276, uint64(p521Uint1(x287)))
+	var x290 uint64
+	var x291 uint64
+	x290, x291 = bits.Add64(x277, x274, uint64(p521Uint1(x289)))
+	var x292 uint64
+	var x293 uint64
+	x292, x293 = bits.Add64(x275, x272, uint64(p521Uint1(x291)))
+	var x294 uint64
+	var x295 uint64
+	x294, x295 = bits.Add64(x273, x270, uint64(p521Uint1(x293)))
+	var x296 uint64
+	var x297 uint64
+	x296, x297 = bits.Add64(x271, x268, uint64(p521Uint1(x295)))
+	var x298 uint64
+	var x299 uint64
+	x298, x299 = bits.Add64(x269, x266, uint64(p521Uint1(x297)))
+	x300 := (uint64(p521Uint1(x299)) + x267)
+	var x302 uint64
+	_, x302 = bits.Add64(x246, x282, uint64(0x0))
+	var x303 uint64
+	var x304 uint64
+	x303, x304 = bits.Add64(x248, x284, uint64(p521Uint1(x302)))
+	var x305 uint64
+	var x306 uint64
+	x305, x306 = bits.Add64(x250, x286, uint64(p521Uint1(x304)))
+	var x307 uint64
+	var x308 uint64
+	x307, x308 = bits.Add64(x252, x288, uint64(p521Uint1(x306)))
+	var x309 uint64
+	var x310 uint64
+	x309, x310 = bits.Add64(x254, x290, uint64(p521Uint1(x308)))
+	var x311 uint64
+	var x312 uint64
+	x311, x312 = bits.Add64(x256, x292, uint64(p521Uint1(x310)))
+	var x313 uint64
+	var x314 uint64
+	x313, x314 = bits.Add64(x258, x294, uint64(p521Uint1(x312)))
+	var x315 uint64
+	var x316 uint64
+	x315, x316 = bits.Add64(x260, x296, uint64(p521Uint1(x314)))
+	var x317 uint64
+	var x318 uint64
+	x317, x318 = bits.Add64(x262, x298, uint64(p521Uint1(x316)))
+	var x319 uint64
+	var x320 uint64
+	x319, x320 = bits.Add64(x264, x300, uint64(p521Uint1(x318)))
+	x321 := (uint64(p521Uint1(x320)) + uint64(p521Uint1(x265)))
+	var x322 uint64
+	var x323 uint64
+	x323, x322 = bits.Mul64(x3, arg1[8])
+	var x324 uint64
+	var x325 uint64
+	x325, x324 = bits.Mul64(x3, arg1[7])
+	var x326 uint64
+	var x327 uint64
+	x327, x326 = bits.Mul64(x3, arg1[6])
+	var x328 uint64
+	var x329 uint64
+	x329, x328 = bits.Mul64(x3, arg1[5])
+	var x330 uint64
+	var x331 uint64
+	x331, x330 = bits.Mul64(x3, arg1[4])
+	var x332 uint64
+	var x333 uint64
+	x333, x332 = bits.Mul64(x3, arg1[3])
+	var x334 uint64
+	var x335 uint64
+	x335, x334 = bits.Mul64(x3, arg1[2])
+	var x336 uint64
+	var x337 uint64
+	x337, x336 = bits.Mul64(x3, arg1[1])
+	var x338 uint64
+	var x339 uint64
+	x339, x338 = bits.Mul64(x3, arg1[0])
+	var x340 uint64
+	var x341 uint64
+	x340, x341 = bits.Add64(x339, x336, uint64(0x0))
+	var x342 uint64
+	var x343 uint64
+	x342, x343 = bits.Add64(x337, x334, uint64(p521Uint1(x341)))
+	var x344 uint64
+	var x345 uint64
+	x344, x345 = bits.Add64(x335, x332, uint64(p521Uint1(x343)))
+	var x346 uint64
+	var x347 uint64
+	x346, x347 = bits.Add64(x333, x330, uint64(p521Uint1(x345)))
+	var x348 uint64
+	var x349 uint64
+	x348, x349 = bits.Add64(x331, x328, uint64(p521Uint1(x347)))
+	var x350 uint64
+	var x351 uint64
+	x350, x351 = bits.Add64(x329, x326, uint64(p521Uint1(x349)))
+	var x352 uint64
+	var x353 uint64
+	x352, x353 = bits.Add64(x327, x324, uint64(p521Uint1(x351)))
+	var x354 uint64
+	var x355 uint64
+	x354, x355 = bits.Add64(x325, x322, uint64(p521Uint1(x353)))
+	x356 := (uint64(p521Uint1(x355)) + x323)
+	var x357 uint64
+	var x358 uint64
+	x357, x358 = bits.Add64(x303, x338, uint64(0x0))
+	var x359 uint64
+	var x360 uint64
+	x359, x360 = bits.Add64(x305, x340, uint64(p521Uint1(x358)))
+	var x361 uint64
+	var x362 uint64
+	x361, x362 = bits.Add64(x307, x342, uint64(p521Uint1(x360)))
+	var x363 uint64
+	var x364 uint64
+	x363, x364 = bits.Add64(x309, x344, uint64(p521Uint1(x362)))
+	var x365 uint64
+	var x366 uint64
+	x365, x366 = bits.Add64(x311, x346, uint64(p521Uint1(x364)))
+	var x367 uint64
+	var x368 uint64
+	x367, x368 = bits.Add64(x313, x348, uint64(p521Uint1(x366)))
+	var x369 uint64
+	var x370 uint64
+	x369, x370 = bits.Add64(x315, x350, uint64(p521Uint1(x368)))
+	var x371 uint64
+	var x372 uint64
+	x371, x372 = bits.Add64(x317, x352, uint64(p521Uint1(x370)))
+	var x373 uint64
+	var x374 uint64
+	x373, x374 = bits.Add64(x319, x354, uint64(p521Uint1(x372)))
+	var x375 uint64
+	var x376 uint64
+	x375, x376 = bits.Add64(x321, x356, uint64(p521Uint1(x374)))
+	var x377 uint64
+	var x378 uint64
+	x378, x377 = bits.Mul64(x357, 0x1ff)
+	var x379 uint64
+	var x380 uint64
+	x380, x379 = bits.Mul64(x357, 0xffffffffffffffff)
+	var x381 uint64
+	var x382 uint64
+	x382, x381 = bits.Mul64(x357, 0xffffffffffffffff)
+	var x383 uint64
+	var x384 uint64
+	x384, x383 = bits.Mul64(x357, 0xffffffffffffffff)
+	var x385 uint64
+	var x386 uint64
+	x386, x385 = bits.Mul64(x357, 0xffffffffffffffff)
+	var x387 uint64
+	var x388 uint64
+	x388, x387 = bits.Mul64(x357, 0xffffffffffffffff)
+	var x389 uint64
+	var x390 uint64
+	x390, x389 = bits.Mul64(x357, 0xffffffffffffffff)
+	var x391 uint64
+	var x392 uint64
+	x392, x391 = bits.Mul64(x357, 0xffffffffffffffff)
+	var x393 uint64
+	var x394 uint64
+	x394, x393 = bits.Mul64(x357, 0xffffffffffffffff)
+	var x395 uint64
+	var x396 uint64
+	x395, x396 = bits.Add64(x394, x391, uint64(0x0))
+	var x397 uint64
+	var x398 uint64
+	x397, x398 = bits.Add64(x392, x389, uint64(p521Uint1(x396)))
+	var x399 uint64
+	var x400 uint64
+	x399, x400 = bits.Add64(x390, x387, uint64(p521Uint1(x398)))
+	var x401 uint64
+	var x402 uint64
+	x401, x402 = bits.Add64(x388, x385, uint64(p521Uint1(x400)))
+	var x403 uint64
+	var x404 uint64
+	x403, x404 = bits.Add64(x386, x383, uint64(p521Uint1(x402)))
+	var x405 uint64
+	var x406 uint64
+	x405, x406 = bits.Add64(x384, x381, uint64(p521Uint1(x404)))
+	var x407 uint64
+	var x408 uint64
+	x407, x408 = bits.Add64(x382, x379, uint64(p521Uint1(x406)))
+	var x409 uint64
+	var x410 uint64
+	x409, x410 = bits.Add64(x380, x377, uint64(p521Uint1(x408)))
+	x411 := (uint64(p521Uint1(x410)) + x378)
+	var x413 uint64
+	_, x413 = bits.Add64(x357, x393, uint64(0x0))
+	var x414 uint64
+	var x415 uint64
+	x414, x415 = bits.Add64(x359, x395, uint64(p521Uint1(x413)))
+	var x416 uint64
+	var x417 uint64
+	x416, x417 = bits.Add64(x361, x397, uint64(p521Uint1(x415)))
+	var x418 uint64
+	var x419 uint64
+	x418, x419 = bits.Add64(x363, x399, uint64(p521Uint1(x417)))
+	var x420 uint64
+	var x421 uint64
+	x420, x421 = bits.Add64(x365, x401, uint64(p521Uint1(x419)))
+	var x422 uint64
+	var x423 uint64
+	x422, x423 = bits.Add64(x367, x403, uint64(p521Uint1(x421)))
+	var x424 uint64
+	var x425 uint64
+	x424, x425 = bits.Add64(x369, x405, uint64(p521Uint1(x423)))
+	var x426 uint64
+	var x427 uint64
+	x426, x427 = bits.Add64(x371, x407, uint64(p521Uint1(x425)))
+	var x428 uint64
+	var x429 uint64
+	x428, x429 = bits.Add64(x373, x409, uint64(p521Uint1(x427)))
+	var x430 uint64
+	var x431 uint64
+	x430, x431 = bits.Add64(x375, x411, uint64(p521Uint1(x429)))
+	x432 := (uint64(p521Uint1(x431)) + uint64(p521Uint1(x376)))
+	var x433 uint64
+	var x434 uint64
+	x434, x433 = bits.Mul64(x4, arg1[8])
+	var x435 uint64
+	var x436 uint64
+	x436, x435 = bits.Mul64(x4, arg1[7])
+	var x437 uint64
+	var x438 uint64
+	x438, x437 = bits.Mul64(x4, arg1[6])
+	var x439 uint64
+	var x440 uint64
+	x440, x439 = bits.Mul64(x4, arg1[5])
+	var x441 uint64
+	var x442 uint64
+	x442, x441 = bits.Mul64(x4, arg1[4])
+	var x443 uint64
+	var x444 uint64
+	x444, x443 = bits.Mul64(x4, arg1[3])
+	var x445 uint64
+	var x446 uint64
+	x446, x445 = bits.Mul64(x4, arg1[2])
+	var x447 uint64
+	var x448 uint64
+	x448, x447 = bits.Mul64(x4, arg1[1])
+	var x449 uint64
+	var x450 uint64
+	x450, x449 = bits.Mul64(x4, arg1[0])
+	var x451 uint64
+	var x452 uint64
+	x451, x452 = bits.Add64(x450, x447, uint64(0x0))
+	var x453 uint64
+	var x454 uint64
+	x453, x454 = bits.Add64(x448, x445, uint64(p521Uint1(x452)))
+	var x455 uint64
+	var x456 uint64
+	x455, x456 = bits.Add64(x446, x443, uint64(p521Uint1(x454)))
+	var x457 uint64
+	var x458 uint64
+	x457, x458 = bits.Add64(x444, x441, uint64(p521Uint1(x456)))
+	var x459 uint64
+	var x460 uint64
+	x459, x460 = bits.Add64(x442, x439, uint64(p521Uint1(x458)))
+	var x461 uint64
+	var x462 uint64
+	x461, x462 = bits.Add64(x440, x437, uint64(p521Uint1(x460)))
+	var x463 uint64
+	var x464 uint64
+	x463, x464 = bits.Add64(x438, x435, uint64(p521Uint1(x462)))
+	var x465 uint64
+	var x466 uint64
+	x465, x466 = bits.Add64(x436, x433, uint64(p521Uint1(x464)))
+	x467 := (uint64(p521Uint1(x466)) + x434)
+	var x468 uint64
+	var x469 uint64
+	x468, x469 = bits.Add64(x414, x449, uint64(0x0))
+	var x470 uint64
+	var x471 uint64
+	x470, x471 = bits.Add64(x416, x451, uint64(p521Uint1(x469)))
+	var x472 uint64
+	var x473 uint64
+	x472, x473 = bits.Add64(x418, x453, uint64(p521Uint1(x471)))
+	var x474 uint64
+	var x475 uint64
+	x474, x475 = bits.Add64(x420, x455, uint64(p521Uint1(x473)))
+	var x476 uint64
+	var x477 uint64
+	x476, x477 = bits.Add64(x422, x457, uint64(p521Uint1(x475)))
+	var x478 uint64
+	var x479 uint64
+	x478, x479 = bits.Add64(x424, x459, uint64(p521Uint1(x477)))
+	var x480 uint64
+	var x481 uint64
+	x480, x481 = bits.Add64(x426, x461, uint64(p521Uint1(x479)))
+	var x482 uint64
+	var x483 uint64
+	x482, x483 = bits.Add64(x428, x463, uint64(p521Uint1(x481)))
+	var x484 uint64
+	var x485 uint64
+	x484, x485 = bits.Add64(x430, x465, uint64(p521Uint1(x483)))
+	var x486 uint64
+	var x487 uint64
+	x486, x487 = bits.Add64(x432, x467, uint64(p521Uint1(x485)))
+	var x488 uint64
+	var x489 uint64
+	x489, x488 = bits.Mul64(x468, 0x1ff)
+	var x490 uint64
+	var x491 uint64
+	x491, x490 = bits.Mul64(x468, 0xffffffffffffffff)
+	var x492 uint64
+	var x493 uint64
+	x493, x492 = bits.Mul64(x468, 0xffffffffffffffff)
+	var x494 uint64
+	var x495 uint64
+	x495, x494 = bits.Mul64(x468, 0xffffffffffffffff)
+	var x496 uint64
+	var x497 uint64
+	x497, x496 = bits.Mul64(x468, 0xffffffffffffffff)
+	var x498 uint64
+	var x499 uint64
+	x499, x498 = bits.Mul64(x468, 0xffffffffffffffff)
+	var x500 uint64
+	var x501 uint64
+	x501, x500 = bits.Mul64(x468, 0xffffffffffffffff)
+	var x502 uint64
+	var x503 uint64
+	x503, x502 = bits.Mul64(x468, 0xffffffffffffffff)
+	var x504 uint64
+	var x505 uint64
+	x505, x504 = bits.Mul64(x468, 0xffffffffffffffff)
+	var x506 uint64
+	var x507 uint64
+	x506, x507 = bits.Add64(x505, x502, uint64(0x0))
+	var x508 uint64
+	var x509 uint64
+	x508, x509 = bits.Add64(x503, x500, uint64(p521Uint1(x507)))
+	var x510 uint64
+	var x511 uint64
+	x510, x511 = bits.Add64(x501, x498, uint64(p521Uint1(x509)))
+	var x512 uint64
+	var x513 uint64
+	x512, x513 = bits.Add64(x499, x496, uint64(p521Uint1(x511)))
+	var x514 uint64
+	var x515 uint64
+	x514, x515 = bits.Add64(x497, x494, uint64(p521Uint1(x513)))
+	var x516 uint64
+	var x517 uint64
+	x516, x517 = bits.Add64(x495, x492, uint64(p521Uint1(x515)))
+	var x518 uint64
+	var x519 uint64
+	x518, x519 = bits.Add64(x493, x490, uint64(p521Uint1(x517)))
+	var x520 uint64
+	var x521 uint64
+	x520, x521 = bits.Add64(x491, x488, uint64(p521Uint1(x519)))
+	x522 := (uint64(p521Uint1(x521)) + x489)
+	var x524 uint64
+	_, x524 = bits.Add64(x468, x504, uint64(0x0))
+	var x525 uint64
+	var x526 uint64
+	x525, x526 = bits.Add64(x470, x506, uint64(p521Uint1(x524)))
+	var x527 uint64
+	var x528 uint64
+	x527, x528 = bits.Add64(x472, x508, uint64(p521Uint1(x526)))
+	var x529 uint64
+	var x530 uint64
+	x529, x530 = bits.Add64(x474, x510, uint64(p521Uint1(x528)))
+	var x531 uint64
+	var x532 uint64
+	x531, x532 = bits.Add64(x476, x512, uint64(p521Uint1(x530)))
+	var x533 uint64
+	var x534 uint64
+	x533, x534 = bits.Add64(x478, x514, uint64(p521Uint1(x532)))
+	var x535 uint64
+	var x536 uint64
+	x535, x536 = bits.Add64(x480, x516, uint64(p521Uint1(x534)))
+	var x537 uint64
+	var x538 uint64
+	x537, x538 = bits.Add64(x482, x518, uint64(p521Uint1(x536)))
+	var x539 uint64
+	var x540 uint64
+	x539, x540 = bits.Add64(x484, x520, uint64(p521Uint1(x538)))
+	var x541 uint64
+	var x542 uint64
+	x541, x542 = bits.Add64(x486, x522, uint64(p521Uint1(x540)))
+	x543 := (uint64(p521Uint1(x542)) + uint64(p521Uint1(x487)))
+	var x544 uint64
+	var x545 uint64
+	x545, x544 = bits.Mul64(x5, arg1[8])
+	var x546 uint64
+	var x547 uint64
+	x547, x546 = bits.Mul64(x5, arg1[7])
+	var x548 uint64
+	var x549 uint64
+	x549, x548 = bits.Mul64(x5, arg1[6])
+	var x550 uint64
+	var x551 uint64
+	x551, x550 = bits.Mul64(x5, arg1[5])
+	var x552 uint64
+	var x553 uint64
+	x553, x552 = bits.Mul64(x5, arg1[4])
+	var x554 uint64
+	var x555 uint64
+	x555, x554 = bits.Mul64(x5, arg1[3])
+	var x556 uint64
+	var x557 uint64
+	x557, x556 = bits.Mul64(x5, arg1[2])
+	var x558 uint64
+	var x559 uint64
+	x559, x558 = bits.Mul64(x5, arg1[1])
+	var x560 uint64
+	var x561 uint64
+	x561, x560 = bits.Mul64(x5, arg1[0])
+	var x562 uint64
+	var x563 uint64
+	x562, x563 = bits.Add64(x561, x558, uint64(0x0))
+	var x564 uint64
+	var x565 uint64
+	x564, x565 = bits.Add64(x559, x556, uint64(p521Uint1(x563)))
+	var x566 uint64
+	var x567 uint64
+	x566, x567 = bits.Add64(x557, x554, uint64(p521Uint1(x565)))
+	var x568 uint64
+	var x569 uint64
+	x568, x569 = bits.Add64(x555, x552, uint64(p521Uint1(x567)))
+	var x570 uint64
+	var x571 uint64
+	x570, x571 = bits.Add64(x553, x550, uint64(p521Uint1(x569)))
+	var x572 uint64
+	var x573 uint64
+	x572, x573 = bits.Add64(x551, x548, uint64(p521Uint1(x571)))
+	var x574 uint64
+	var x575 uint64
+	x574, x575 = bits.Add64(x549, x546, uint64(p521Uint1(x573)))
+	var x576 uint64
+	var x577 uint64
+	x576, x577 = bits.Add64(x547, x544, uint64(p521Uint1(x575)))
+	x578 := (uint64(p521Uint1(x577)) + x545)
+	var x579 uint64
+	var x580 uint64
+	x579, x580 = bits.Add64(x525, x560, uint64(0x0))
+	var x581 uint64
+	var x582 uint64
+	x581, x582 = bits.Add64(x527, x562, uint64(p521Uint1(x580)))
+	var x583 uint64
+	var x584 uint64
+	x583, x584 = bits.Add64(x529, x564, uint64(p521Uint1(x582)))
+	var x585 uint64
+	var x586 uint64
+	x585, x586 = bits.Add64(x531, x566, uint64(p521Uint1(x584)))
+	var x587 uint64
+	var x588 uint64
+	x587, x588 = bits.Add64(x533, x568, uint64(p521Uint1(x586)))
+	var x589 uint64
+	var x590 uint64
+	x589, x590 = bits.Add64(x535, x570, uint64(p521Uint1(x588)))
+	var x591 uint64
+	var x592 uint64
+	x591, x592 = bits.Add64(x537, x572, uint64(p521Uint1(x590)))
+	var x593 uint64
+	var x594 uint64
+	x593, x594 = bits.Add64(x539, x574, uint64(p521Uint1(x592)))
+	var x595 uint64
+	var x596 uint64
+	x595, x596 = bits.Add64(x541, x576, uint64(p521Uint1(x594)))
+	var x597 uint64
+	var x598 uint64
+	x597, x598 = bits.Add64(x543, x578, uint64(p521Uint1(x596)))
+	var x599 uint64
+	var x600 uint64
+	x600, x599 = bits.Mul64(x579, 0x1ff)
+	var x601 uint64
+	var x602 uint64
+	x602, x601 = bits.Mul64(x579, 0xffffffffffffffff)
+	var x603 uint64
+	var x604 uint64
+	x604, x603 = bits.Mul64(x579, 0xffffffffffffffff)
+	var x605 uint64
+	var x606 uint64
+	x606, x605 = bits.Mul64(x579, 0xffffffffffffffff)
+	var x607 uint64
+	var x608 uint64
+	x608, x607 = bits.Mul64(x579, 0xffffffffffffffff)
+	var x609 uint64
+	var x610 uint64
+	x610, x609 = bits.Mul64(x579, 0xffffffffffffffff)
+	var x611 uint64
+	var x612 uint64
+	x612, x611 = bits.Mul64(x579, 0xffffffffffffffff)
+	var x613 uint64
+	var x614 uint64
+	x614, x613 = bits.Mul64(x579, 0xffffffffffffffff)
+	var x615 uint64
+	var x616 uint64
+	x616, x615 = bits.Mul64(x579, 0xffffffffffffffff)
+	var x617 uint64
+	var x618 uint64
+	x617, x618 = bits.Add64(x616, x613, uint64(0x0))
+	var x619 uint64
+	var x620 uint64
+	x619, x620 = bits.Add64(x614, x611, uint64(p521Uint1(x618)))
+	var x621 uint64
+	var x622 uint64
+	x621, x622 = bits.Add64(x612, x609, uint64(p521Uint1(x620)))
+	var x623 uint64
+	var x624 uint64
+	x623, x624 = bits.Add64(x610, x607, uint64(p521Uint1(x622)))
+	var x625 uint64
+	var x626 uint64
+	x625, x626 = bits.Add64(x608, x605, uint64(p521Uint1(x624)))
+	var x627 uint64
+	var x628 uint64
+	x627, x628 = bits.Add64(x606, x603, uint64(p521Uint1(x626)))
+	var x629 uint64
+	var x630 uint64
+	x629, x630 = bits.Add64(x604, x601, uint64(p521Uint1(x628)))
+	var x631 uint64
+	var x632 uint64
+	x631, x632 = bits.Add64(x602, x599, uint64(p521Uint1(x630)))
+	x633 := (uint64(p521Uint1(x632)) + x600)
+	var x635 uint64
+	_, x635 = bits.Add64(x579, x615, uint64(0x0))
+	var x636 uint64
+	var x637 uint64
+	x636, x637 = bits.Add64(x581, x617, uint64(p521Uint1(x635)))
+	var x638 uint64
+	var x639 uint64
+	x638, x639 = bits.Add64(x583, x619, uint64(p521Uint1(x637)))
+	var x640 uint64
+	var x641 uint64
+	x640, x641 = bits.Add64(x585, x621, uint64(p521Uint1(x639)))
+	var x642 uint64
+	var x643 uint64
+	x642, x643 = bits.Add64(x587, x623, uint64(p521Uint1(x641)))
+	var x644 uint64
+	var x645 uint64
+	x644, x645 = bits.Add64(x589, x625, uint64(p521Uint1(x643)))
+	var x646 uint64
+	var x647 uint64
+	x646, x647 = bits.Add64(x591, x627, uint64(p521Uint1(x645)))
+	var x648 uint64
+	var x649 uint64
+	x648, x649 = bits.Add64(x593, x629, uint64(p521Uint1(x647)))
+	var x650 uint64
+	var x651 uint64
+	x650, x651 = bits.Add64(x595, x631, uint64(p521Uint1(x649)))
+	var x652 uint64
+	var x653 uint64
+	x652, x653 = bits.Add64(x597, x633, uint64(p521Uint1(x651)))
+	x654 := (uint64(p521Uint1(x653)) + uint64(p521Uint1(x598)))
+	var x655 uint64
+	var x656 uint64
+	x656, x655 = bits.Mul64(x6, arg1[8])
+	var x657 uint64
+	var x658 uint64
+	x658, x657 = bits.Mul64(x6, arg1[7])
+	var x659 uint64
+	var x660 uint64
+	x660, x659 = bits.Mul64(x6, arg1[6])
+	var x661 uint64
+	var x662 uint64
+	x662, x661 = bits.Mul64(x6, arg1[5])
+	var x663 uint64
+	var x664 uint64
+	x664, x663 = bits.Mul64(x6, arg1[4])
+	var x665 uint64
+	var x666 uint64
+	x666, x665 = bits.Mul64(x6, arg1[3])
+	var x667 uint64
+	var x668 uint64
+	x668, x667 = bits.Mul64(x6, arg1[2])
+	var x669 uint64
+	var x670 uint64
+	x670, x669 = bits.Mul64(x6, arg1[1])
+	var x671 uint64
+	var x672 uint64
+	x672, x671 = bits.Mul64(x6, arg1[0])
+	var x673 uint64
+	var x674 uint64
+	x673, x674 = bits.Add64(x672, x669, uint64(0x0))
+	var x675 uint64
+	var x676 uint64
+	x675, x676 = bits.Add64(x670, x667, uint64(p521Uint1(x674)))
+	var x677 uint64
+	var x678 uint64
+	x677, x678 = bits.Add64(x668, x665, uint64(p521Uint1(x676)))
+	var x679 uint64
+	var x680 uint64
+	x679, x680 = bits.Add64(x666, x663, uint64(p521Uint1(x678)))
+	var x681 uint64
+	var x682 uint64
+	x681, x682 = bits.Add64(x664, x661, uint64(p521Uint1(x680)))
+	var x683 uint64
+	var x684 uint64
+	x683, x684 = bits.Add64(x662, x659, uint64(p521Uint1(x682)))
+	var x685 uint64
+	var x686 uint64
+	x685, x686 = bits.Add64(x660, x657, uint64(p521Uint1(x684)))
+	var x687 uint64
+	var x688 uint64
+	x687, x688 = bits.Add64(x658, x655, uint64(p521Uint1(x686)))
+	x689 := (uint64(p521Uint1(x688)) + x656)
+	var x690 uint64
+	var x691 uint64
+	x690, x691 = bits.Add64(x636, x671, uint64(0x0))
+	var x692 uint64
+	var x693 uint64
+	x692, x693 = bits.Add64(x638, x673, uint64(p521Uint1(x691)))
+	var x694 uint64
+	var x695 uint64
+	x694, x695 = bits.Add64(x640, x675, uint64(p521Uint1(x693)))
+	var x696 uint64
+	var x697 uint64
+	x696, x697 = bits.Add64(x642, x677, uint64(p521Uint1(x695)))
+	var x698 uint64
+	var x699 uint64
+	x698, x699 = bits.Add64(x644, x679, uint64(p521Uint1(x697)))
+	var x700 uint64
+	var x701 uint64
+	x700, x701 = bits.Add64(x646, x681, uint64(p521Uint1(x699)))
+	var x702 uint64
+	var x703 uint64
+	x702, x703 = bits.Add64(x648, x683, uint64(p521Uint1(x701)))
+	var x704 uint64
+	var x705 uint64
+	x704, x705 = bits.Add64(x650, x685, uint64(p521Uint1(x703)))
+	var x706 uint64
+	var x707 uint64
+	x706, x707 = bits.Add64(x652, x687, uint64(p521Uint1(x705)))
+	var x708 uint64
+	var x709 uint64
+	x708, x709 = bits.Add64(x654, x689, uint64(p521Uint1(x707)))
+	var x710 uint64
+	var x711 uint64
+	x711, x710 = bits.Mul64(x690, 0x1ff)
+	var x712 uint64
+	var x713 uint64
+	x713, x712 = bits.Mul64(x690, 0xffffffffffffffff)
+	var x714 uint64
+	var x715 uint64
+	x715, x714 = bits.Mul64(x690, 0xffffffffffffffff)
+	var x716 uint64
+	var x717 uint64
+	x717, x716 = bits.Mul64(x690, 0xffffffffffffffff)
+	var x718 uint64
+	var x719 uint64
+	x719, x718 = bits.Mul64(x690, 0xffffffffffffffff)
+	var x720 uint64
+	var x721 uint64
+	x721, x720 = bits.Mul64(x690, 0xffffffffffffffff)
+	var x722 uint64
+	var x723 uint64
+	x723, x722 = bits.Mul64(x690, 0xffffffffffffffff)
+	var x724 uint64
+	var x725 uint64
+	x725, x724 = bits.Mul64(x690, 0xffffffffffffffff)
+	var x726 uint64
+	var x727 uint64
+	x727, x726 = bits.Mul64(x690, 0xffffffffffffffff)
+	var x728 uint64
+	var x729 uint64
+	x728, x729 = bits.Add64(x727, x724, uint64(0x0))
+	var x730 uint64
+	var x731 uint64
+	x730, x731 = bits.Add64(x725, x722, uint64(p521Uint1(x729)))
+	var x732 uint64
+	var x733 uint64
+	x732, x733 = bits.Add64(x723, x720, uint64(p521Uint1(x731)))
+	var x734 uint64
+	var x735 uint64
+	x734, x735 = bits.Add64(x721, x718, uint64(p521Uint1(x733)))
+	var x736 uint64
+	var x737 uint64
+	x736, x737 = bits.Add64(x719, x716, uint64(p521Uint1(x735)))
+	var x738 uint64
+	var x739 uint64
+	x738, x739 = bits.Add64(x717, x714, uint64(p521Uint1(x737)))
+	var x740 uint64
+	var x741 uint64
+	x740, x741 = bits.Add64(x715, x712, uint64(p521Uint1(x739)))
+	var x742 uint64
+	var x743 uint64
+	x742, x743 = bits.Add64(x713, x710, uint64(p521Uint1(x741)))
+	x744 := (uint64(p521Uint1(x743)) + x711)
+	var x746 uint64
+	_, x746 = bits.Add64(x690, x726, uint64(0x0))
+	var x747 uint64
+	var x748 uint64
+	x747, x748 = bits.Add64(x692, x728, uint64(p521Uint1(x746)))
+	var x749 uint64
+	var x750 uint64
+	x749, x750 = bits.Add64(x694, x730, uint64(p521Uint1(x748)))
+	var x751 uint64
+	var x752 uint64
+	x751, x752 = bits.Add64(x696, x732, uint64(p521Uint1(x750)))
+	var x753 uint64
+	var x754 uint64
+	x753, x754 = bits.Add64(x698, x734, uint64(p521Uint1(x752)))
+	var x755 uint64
+	var x756 uint64
+	x755, x756 = bits.Add64(x700, x736, uint64(p521Uint1(x754)))
+	var x757 uint64
+	var x758 uint64
+	x757, x758 = bits.Add64(x702, x738, uint64(p521Uint1(x756)))
+	var x759 uint64
+	var x760 uint64
+	x759, x760 = bits.Add64(x704, x740, uint64(p521Uint1(x758)))
+	var x761 uint64
+	var x762 uint64
+	x761, x762 = bits.Add64(x706, x742, uint64(p521Uint1(x760)))
+	var x763 uint64
+	var x764 uint64
+	x763, x764 = bits.Add64(x708, x744, uint64(p521Uint1(x762)))
+	x765 := (uint64(p521Uint1(x764)) + uint64(p521Uint1(x709)))
+	var x766 uint64
+	var x767 uint64
+	x767, x766 = bits.Mul64(x7, arg1[8])
+	var x768 uint64
+	var x769 uint64
+	x769, x768 = bits.Mul64(x7, arg1[7])
+	var x770 uint64
+	var x771 uint64
+	x771, x770 = bits.Mul64(x7, arg1[6])
+	var x772 uint64
+	var x773 uint64
+	x773, x772 = bits.Mul64(x7, arg1[5])
+	var x774 uint64
+	var x775 uint64
+	x775, x774 = bits.Mul64(x7, arg1[4])
+	var x776 uint64
+	var x777 uint64
+	x777, x776 = bits.Mul64(x7, arg1[3])
+	var x778 uint64
+	var x779 uint64
+	x779, x778 = bits.Mul64(x7, arg1[2])
+	var x780 uint64
+	var x781 uint64
+	x781, x780 = bits.Mul64(x7, arg1[1])
+	var x782 uint64
+	var x783 uint64
+	x783, x782 = bits.Mul64(x7, arg1[0])
+	var x784 uint64
+	var x785 uint64
+	x784, x785 = bits.Add64(x783, x780, uint64(0x0))
+	var x786 uint64
+	var x787 uint64
+	x786, x787 = bits.Add64(x781, x778, uint64(p521Uint1(x785)))
+	var x788 uint64
+	var x789 uint64
+	x788, x789 = bits.Add64(x779, x776, uint64(p521Uint1(x787)))
+	var x790 uint64
+	var x791 uint64
+	x790, x791 = bits.Add64(x777, x774, uint64(p521Uint1(x789)))
+	var x792 uint64
+	var x793 uint64
+	x792, x793 = bits.Add64(x775, x772, uint64(p521Uint1(x791)))
+	var x794 uint64
+	var x795 uint64
+	x794, x795 = bits.Add64(x773, x770, uint64(p521Uint1(x793)))
+	var x796 uint64
+	var x797 uint64
+	x796, x797 = bits.Add64(x771, x768, uint64(p521Uint1(x795)))
+	var x798 uint64
+	var x799 uint64
+	x798, x799 = bits.Add64(x769, x766, uint64(p521Uint1(x797)))
+	x800 := (uint64(p521Uint1(x799)) + x767)
+	var x801 uint64
+	var x802 uint64
+	x801, x802 = bits.Add64(x747, x782, uint64(0x0))
+	var x803 uint64
+	var x804 uint64
+	x803, x804 = bits.Add64(x749, x784, uint64(p521Uint1(x802)))
+	var x805 uint64
+	var x806 uint64
+	x805, x806 = bits.Add64(x751, x786, uint64(p521Uint1(x804)))
+	var x807 uint64
+	var x808 uint64
+	x807, x808 = bits.Add64(x753, x788, uint64(p521Uint1(x806)))
+	var x809 uint64
+	var x810 uint64
+	x809, x810 = bits.Add64(x755, x790, uint64(p521Uint1(x808)))
+	var x811 uint64
+	var x812 uint64
+	x811, x812 = bits.Add64(x757, x792, uint64(p521Uint1(x810)))
+	var x813 uint64
+	var x814 uint64
+	x813, x814 = bits.Add64(x759, x794, uint64(p521Uint1(x812)))
+	var x815 uint64
+	var x816 uint64
+	x815, x816 = bits.Add64(x761, x796, uint64(p521Uint1(x814)))
+	var x817 uint64
+	var x818 uint64
+	x817, x818 = bits.Add64(x763, x798, uint64(p521Uint1(x816)))
+	var x819 uint64
+	var x820 uint64
+	x819, x820 = bits.Add64(x765, x800, uint64(p521Uint1(x818)))
+	var x821 uint64
+	var x822 uint64
+	x822, x821 = bits.Mul64(x801, 0x1ff)
+	var x823 uint64
+	var x824 uint64
+	x824, x823 = bits.Mul64(x801, 0xffffffffffffffff)
+	var x825 uint64
+	var x826 uint64
+	x826, x825 = bits.Mul64(x801, 0xffffffffffffffff)
+	var x827 uint64
+	var x828 uint64
+	x828, x827 = bits.Mul64(x801, 0xffffffffffffffff)
+	var x829 uint64
+	var x830 uint64
+	x830, x829 = bits.Mul64(x801, 0xffffffffffffffff)
+	var x831 uint64
+	var x832 uint64
+	x832, x831 = bits.Mul64(x801, 0xffffffffffffffff)
+	var x833 uint64
+	var x834 uint64
+	x834, x833 = bits.Mul64(x801, 0xffffffffffffffff)
+	var x835 uint64
+	var x836 uint64
+	x836, x835 = bits.Mul64(x801, 0xffffffffffffffff)
+	var x837 uint64
+	var x838 uint64
+	x838, x837 = bits.Mul64(x801, 0xffffffffffffffff)
+	var x839 uint64
+	var x840 uint64
+	x839, x840 = bits.Add64(x838, x835, uint64(0x0))
+	var x841 uint64
+	var x842 uint64
+	x841, x842 = bits.Add64(x836, x833, uint64(p521Uint1(x840)))
+	var x843 uint64
+	var x844 uint64
+	x843, x844 = bits.Add64(x834, x831, uint64(p521Uint1(x842)))
+	var x845 uint64
+	var x846 uint64
+	x845, x846 = bits.Add64(x832, x829, uint64(p521Uint1(x844)))
+	var x847 uint64
+	var x848 uint64
+	x847, x848 = bits.Add64(x830, x827, uint64(p521Uint1(x846)))
+	var x849 uint64
+	var x850 uint64
+	x849, x850 = bits.Add64(x828, x825, uint64(p521Uint1(x848)))
+	var x851 uint64
+	var x852 uint64
+	x851, x852 = bits.Add64(x826, x823, uint64(p521Uint1(x850)))
+	var x853 uint64
+	var x854 uint64
+	x853, x854 = bits.Add64(x824, x821, uint64(p521Uint1(x852)))
+	x855 := (uint64(p521Uint1(x854)) + x822)
+	var x857 uint64
+	_, x857 = bits.Add64(x801, x837, uint64(0x0))
+	var x858 uint64
+	var x859 uint64
+	x858, x859 = bits.Add64(x803, x839, uint64(p521Uint1(x857)))
+	var x860 uint64
+	var x861 uint64
+	x860, x861 = bits.Add64(x805, x841, uint64(p521Uint1(x859)))
+	var x862 uint64
+	var x863 uint64
+	x862, x863 = bits.Add64(x807, x843, uint64(p521Uint1(x861)))
+	var x864 uint64
+	var x865 uint64
+	x864, x865 = bits.Add64(x809, x845, uint64(p521Uint1(x863)))
+	var x866 uint64
+	var x867 uint64
+	x866, x867 = bits.Add64(x811, x847, uint64(p521Uint1(x865)))
+	var x868 uint64
+	var x869 uint64
+	x868, x869 = bits.Add64(x813, x849, uint64(p521Uint1(x867)))
+	var x870 uint64
+	var x871 uint64
+	x870, x871 = bits.Add64(x815, x851, uint64(p521Uint1(x869)))
+	var x872 uint64
+	var x873 uint64
+	x872, x873 = bits.Add64(x817, x853, uint64(p521Uint1(x871)))
+	var x874 uint64
+	var x875 uint64
+	x874, x875 = bits.Add64(x819, x855, uint64(p521Uint1(x873)))
+	x876 := (uint64(p521Uint1(x875)) + uint64(p521Uint1(x820)))
+	var x877 uint64
+	var x878 uint64
+	x878, x877 = bits.Mul64(x8, arg1[8])
+	var x879 uint64
+	var x880 uint64
+	x880, x879 = bits.Mul64(x8, arg1[7])
+	var x881 uint64
+	var x882 uint64
+	x882, x881 = bits.Mul64(x8, arg1[6])
+	var x883 uint64
+	var x884 uint64
+	x884, x883 = bits.Mul64(x8, arg1[5])
+	var x885 uint64
+	var x886 uint64
+	x886, x885 = bits.Mul64(x8, arg1[4])
+	var x887 uint64
+	var x888 uint64
+	x888, x887 = bits.Mul64(x8, arg1[3])
+	var x889 uint64
+	var x890 uint64
+	x890, x889 = bits.Mul64(x8, arg1[2])
+	var x891 uint64
+	var x892 uint64
+	x892, x891 = bits.Mul64(x8, arg1[1])
+	var x893 uint64
+	var x894 uint64
+	x894, x893 = bits.Mul64(x8, arg1[0])
+	var x895 uint64
+	var x896 uint64
+	x895, x896 = bits.Add64(x894, x891, uint64(0x0))
+	var x897 uint64
+	var x898 uint64
+	x897, x898 = bits.Add64(x892, x889, uint64(p521Uint1(x896)))
+	var x899 uint64
+	var x900 uint64
+	x899, x900 = bits.Add64(x890, x887, uint64(p521Uint1(x898)))
+	var x901 uint64
+	var x902 uint64
+	x901, x902 = bits.Add64(x888, x885, uint64(p521Uint1(x900)))
+	var x903 uint64
+	var x904 uint64
+	x903, x904 = bits.Add64(x886, x883, uint64(p521Uint1(x902)))
+	var x905 uint64
+	var x906 uint64
+	x905, x906 = bits.Add64(x884, x881, uint64(p521Uint1(x904)))
+	var x907 uint64
+	var x908 uint64
+	x907, x908 = bits.Add64(x882, x879, uint64(p521Uint1(x906)))
+	var x909 uint64
+	var x910 uint64
+	x909, x910 = bits.Add64(x880, x877, uint64(p521Uint1(x908)))
+	x911 := (uint64(p521Uint1(x910)) + x878)
+	var x912 uint64
+	var x913 uint64
+	x912, x913 = bits.Add64(x858, x893, uint64(0x0))
+	var x914 uint64
+	var x915 uint64
+	x914, x915 = bits.Add64(x860, x895, uint64(p521Uint1(x913)))
+	var x916 uint64
+	var x917 uint64
+	x916, x917 = bits.Add64(x862, x897, uint64(p521Uint1(x915)))
+	var x918 uint64
+	var x919 uint64
+	x918, x919 = bits.Add64(x864, x899, uint64(p521Uint1(x917)))
+	var x920 uint64
+	var x921 uint64
+	x920, x921 = bits.Add64(x866, x901, uint64(p521Uint1(x919)))
+	var x922 uint64
+	var x923 uint64
+	x922, x923 = bits.Add64(x868, x903, uint64(p521Uint1(x921)))
+	var x924 uint64
+	var x925 uint64
+	x924, x925 = bits.Add64(x870, x905, uint64(p521Uint1(x923)))
+	var x926 uint64
+	var x927 uint64
+	x926, x927 = bits.Add64(x872, x907, uint64(p521Uint1(x925)))
+	var x928 uint64
+	var x929 uint64
+	x928, x929 = bits.Add64(x874, x909, uint64(p521Uint1(x927)))
+	var x930 uint64
+	var x931 uint64
+	x930, x931 = bits.Add64(x876, x911, uint64(p521Uint1(x929)))
+	var x932 uint64
+	var x933 uint64
+	x933, x932 = bits.Mul64(x912, 0x1ff)
+	var x934 uint64
+	var x935 uint64
+	x935, x934 = bits.Mul64(x912, 0xffffffffffffffff)
+	var x936 uint64
+	var x937 uint64
+	x937, x936 = bits.Mul64(x912, 0xffffffffffffffff)
+	var x938 uint64
+	var x939 uint64
+	x939, x938 = bits.Mul64(x912, 0xffffffffffffffff)
+	var x940 uint64
+	var x941 uint64
+	x941, x940 = bits.Mul64(x912, 0xffffffffffffffff)
+	var x942 uint64
+	var x943 uint64
+	x943, x942 = bits.Mul64(x912, 0xffffffffffffffff)
+	var x944 uint64
+	var x945 uint64
+	x945, x944 = bits.Mul64(x912, 0xffffffffffffffff)
+	var x946 uint64
+	var x947 uint64
+	x947, x946 = bits.Mul64(x912, 0xffffffffffffffff)
+	var x948 uint64
+	var x949 uint64
+	x949, x948 = bits.Mul64(x912, 0xffffffffffffffff)
+	var x950 uint64
+	var x951 uint64
+	x950, x951 = bits.Add64(x949, x946, uint64(0x0))
+	var x952 uint64
+	var x953 uint64
+	x952, x953 = bits.Add64(x947, x944, uint64(p521Uint1(x951)))
+	var x954 uint64
+	var x955 uint64
+	x954, x955 = bits.Add64(x945, x942, uint64(p521Uint1(x953)))
+	var x956 uint64
+	var x957 uint64
+	x956, x957 = bits.Add64(x943, x940, uint64(p521Uint1(x955)))
+	var x958 uint64
+	var x959 uint64
+	x958, x959 = bits.Add64(x941, x938, uint64(p521Uint1(x957)))
+	var x960 uint64
+	var x961 uint64
+	x960, x961 = bits.Add64(x939, x936, uint64(p521Uint1(x959)))
+	var x962 uint64
+	var x963 uint64
+	x962, x963 = bits.Add64(x937, x934, uint64(p521Uint1(x961)))
+	var x964 uint64
+	var x965 uint64
+	x964, x965 = bits.Add64(x935, x932, uint64(p521Uint1(x963)))
+	x966 := (uint64(p521Uint1(x965)) + x933)
+	var x968 uint64
+	_, x968 = bits.Add64(x912, x948, uint64(0x0))
+	var x969 uint64
+	var x970 uint64
+	x969, x970 = bits.Add64(x914, x950, uint64(p521Uint1(x968)))
+	var x971 uint64
+	var x972 uint64
+	x971, x972 = bits.Add64(x916, x952, uint64(p521Uint1(x970)))
+	var x973 uint64
+	var x974 uint64
+	x973, x974 = bits.Add64(x918, x954, uint64(p521Uint1(x972)))
+	var x975 uint64
+	var x976 uint64
+	x975, x976 = bits.Add64(x920, x956, uint64(p521Uint1(x974)))
+	var x977 uint64
+	var x978 uint64
+	x977, x978 = bits.Add64(x922, x958, uint64(p521Uint1(x976)))
+	var x979 uint64
+	var x980 uint64
+	x979, x980 = bits.Add64(x924, x960, uint64(p521Uint1(x978)))
+	var x981 uint64
+	var x982 uint64
+	x981, x982 = bits.Add64(x926, x962, uint64(p521Uint1(x980)))
+	var x983 uint64
+	var x984 uint64
+	x983, x984 = bits.Add64(x928, x964, uint64(p521Uint1(x982)))
+	var x985 uint64
+	var x986 uint64
+	x985, x986 = bits.Add64(x930, x966, uint64(p521Uint1(x984)))
+	x987 := (uint64(p521Uint1(x986)) + uint64(p521Uint1(x931)))
+	var x988 uint64
+	var x989 uint64
+	x988, x989 = bits.Sub64(x969, 0xffffffffffffffff, uint64(0x0))
+	var x990 uint64
+	var x991 uint64
+	x990, x991 = bits.Sub64(x971, 0xffffffffffffffff, uint64(p521Uint1(x989)))
+	var x992 uint64
+	var x993 uint64
+	x992, x993 = bits.Sub64(x973, 0xffffffffffffffff, uint64(p521Uint1(x991)))
+	var x994 uint64
+	var x995 uint64
+	x994, x995 = bits.Sub64(x975, 0xffffffffffffffff, uint64(p521Uint1(x993)))
+	var x996 uint64
+	var x997 uint64
+	x996, x997 = bits.Sub64(x977, 0xffffffffffffffff, uint64(p521Uint1(x995)))
+	var x998 uint64
+	var x999 uint64
+	x998, x999 = bits.Sub64(x979, 0xffffffffffffffff, uint64(p521Uint1(x997)))
+	var x1000 uint64
+	var x1001 uint64
+	x1000, x1001 = bits.Sub64(x981, 0xffffffffffffffff, uint64(p521Uint1(x999)))
+	var x1002 uint64
+	var x1003 uint64
+	x1002, x1003 = bits.Sub64(x983, 0xffffffffffffffff, uint64(p521Uint1(x1001)))
+	var x1004 uint64
+	var x1005 uint64
+	x1004, x1005 = bits.Sub64(x985, 0x1ff, uint64(p521Uint1(x1003)))
+	var x1007 uint64
+	_, x1007 = bits.Sub64(x987, uint64(0x0), uint64(p521Uint1(x1005)))
+	var x1008 uint64
+	p521CmovznzU64(&x1008, p521Uint1(x1007), x988, x969)
+	var x1009 uint64
+	p521CmovznzU64(&x1009, p521Uint1(x1007), x990, x971)
+	var x1010 uint64
+	p521CmovznzU64(&x1010, p521Uint1(x1007), x992, x973)
+	var x1011 uint64
+	p521CmovznzU64(&x1011, p521Uint1(x1007), x994, x975)
+	var x1012 uint64
+	p521CmovznzU64(&x1012, p521Uint1(x1007), x996, x977)
+	var x1013 uint64
+	p521CmovznzU64(&x1013, p521Uint1(x1007), x998, x979)
+	var x1014 uint64
+	p521CmovznzU64(&x1014, p521Uint1(x1007), x1000, x981)
+	var x1015 uint64
+	p521CmovznzU64(&x1015, p521Uint1(x1007), x1002, x983)
+	var x1016 uint64
+	p521CmovznzU64(&x1016, p521Uint1(x1007), x1004, x985)
+	out1[0] = x1008
+	out1[1] = x1009
+	out1[2] = x1010
+	out1[3] = x1011
+	out1[4] = x1012
+	out1[5] = x1013
+	out1[6] = x1014
+	out1[7] = x1015
+	out1[8] = x1016
+}
+
+// p521Add adds two field elements in the Montgomery domain.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//	0 ≤ eval arg2 < m
+//
+// Postconditions:
+//
+//	eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) + eval (from_montgomery arg2)) mod m
+//	0 ≤ eval out1 < m
+func p521Add(out1 *p521MontgomeryDomainFieldElement, arg1 *p521MontgomeryDomainFieldElement, arg2 *p521MontgomeryDomainFieldElement) {
+	var x1 uint64
+	var x2 uint64
+	x1, x2 = bits.Add64(arg1[0], arg2[0], uint64(0x0))
+	var x3 uint64
+	var x4 uint64
+	x3, x4 = bits.Add64(arg1[1], arg2[1], uint64(p521Uint1(x2)))
+	var x5 uint64
+	var x6 uint64
+	x5, x6 = bits.Add64(arg1[2], arg2[2], uint64(p521Uint1(x4)))
+	var x7 uint64
+	var x8 uint64
+	x7, x8 = bits.Add64(arg1[3], arg2[3], uint64(p521Uint1(x6)))
+	var x9 uint64
+	var x10 uint64
+	x9, x10 = bits.Add64(arg1[4], arg2[4], uint64(p521Uint1(x8)))
+	var x11 uint64
+	var x12 uint64
+	x11, x12 = bits.Add64(arg1[5], arg2[5], uint64(p521Uint1(x10)))
+	var x13 uint64
+	var x14 uint64
+	x13, x14 = bits.Add64(arg1[6], arg2[6], uint64(p521Uint1(x12)))
+	var x15 uint64
+	var x16 uint64
+	x15, x16 = bits.Add64(arg1[7], arg2[7], uint64(p521Uint1(x14)))
+	var x17 uint64
+	var x18 uint64
+	x17, x18 = bits.Add64(arg1[8], arg2[8], uint64(p521Uint1(x16)))
+	var x19 uint64
+	var x20 uint64
+	x19, x20 = bits.Sub64(x1, 0xffffffffffffffff, uint64(0x0))
+	var x21 uint64
+	var x22 uint64
+	x21, x22 = bits.Sub64(x3, 0xffffffffffffffff, uint64(p521Uint1(x20)))
+	var x23 uint64
+	var x24 uint64
+	x23, x24 = bits.Sub64(x5, 0xffffffffffffffff, uint64(p521Uint1(x22)))
+	var x25 uint64
+	var x26 uint64
+	x25, x26 = bits.Sub64(x7, 0xffffffffffffffff, uint64(p521Uint1(x24)))
+	var x27 uint64
+	var x28 uint64
+	x27, x28 = bits.Sub64(x9, 0xffffffffffffffff, uint64(p521Uint1(x26)))
+	var x29 uint64
+	var x30 uint64
+	x29, x30 = bits.Sub64(x11, 0xffffffffffffffff, uint64(p521Uint1(x28)))
+	var x31 uint64
+	var x32 uint64
+	x31, x32 = bits.Sub64(x13, 0xffffffffffffffff, uint64(p521Uint1(x30)))
+	var x33 uint64
+	var x34 uint64
+	x33, x34 = bits.Sub64(x15, 0xffffffffffffffff, uint64(p521Uint1(x32)))
+	var x35 uint64
+	var x36 uint64
+	x35, x36 = bits.Sub64(x17, 0x1ff, uint64(p521Uint1(x34)))
+	var x38 uint64
+	_, x38 = bits.Sub64(uint64(p521Uint1(x18)), uint64(0x0), uint64(p521Uint1(x36)))
+	var x39 uint64
+	p521CmovznzU64(&x39, p521Uint1(x38), x19, x1)
+	var x40 uint64
+	p521CmovznzU64(&x40, p521Uint1(x38), x21, x3)
+	var x41 uint64
+	p521CmovznzU64(&x41, p521Uint1(x38), x23, x5)
+	var x42 uint64
+	p521CmovznzU64(&x42, p521Uint1(x38), x25, x7)
+	var x43 uint64
+	p521CmovznzU64(&x43, p521Uint1(x38), x27, x9)
+	var x44 uint64
+	p521CmovznzU64(&x44, p521Uint1(x38), x29, x11)
+	var x45 uint64
+	p521CmovznzU64(&x45, p521Uint1(x38), x31, x13)
+	var x46 uint64
+	p521CmovznzU64(&x46, p521Uint1(x38), x33, x15)
+	var x47 uint64
+	p521CmovznzU64(&x47, p521Uint1(x38), x35, x17)
+	out1[0] = x39
+	out1[1] = x40
+	out1[2] = x41
+	out1[3] = x42
+	out1[4] = x43
+	out1[5] = x44
+	out1[6] = x45
+	out1[7] = x46
+	out1[8] = x47
+}
+
+// p521Sub subtracts two field elements in the Montgomery domain.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//	0 ≤ eval arg2 < m
+//
+// Postconditions:
+//
+//	eval (from_montgomery out1) mod m = (eval (from_montgomery arg1) - eval (from_montgomery arg2)) mod m
+//	0 ≤ eval out1 < m
+func p521Sub(out1 *p521MontgomeryDomainFieldElement, arg1 *p521MontgomeryDomainFieldElement, arg2 *p521MontgomeryDomainFieldElement) {
+	var x1 uint64
+	var x2 uint64
+	x1, x2 = bits.Sub64(arg1[0], arg2[0], uint64(0x0))
+	var x3 uint64
+	var x4 uint64
+	x3, x4 = bits.Sub64(arg1[1], arg2[1], uint64(p521Uint1(x2)))
+	var x5 uint64
+	var x6 uint64
+	x5, x6 = bits.Sub64(arg1[2], arg2[2], uint64(p521Uint1(x4)))
+	var x7 uint64
+	var x8 uint64
+	x7, x8 = bits.Sub64(arg1[3], arg2[3], uint64(p521Uint1(x6)))
+	var x9 uint64
+	var x10 uint64
+	x9, x10 = bits.Sub64(arg1[4], arg2[4], uint64(p521Uint1(x8)))
+	var x11 uint64
+	var x12 uint64
+	x11, x12 = bits.Sub64(arg1[5], arg2[5], uint64(p521Uint1(x10)))
+	var x13 uint64
+	var x14 uint64
+	x13, x14 = bits.Sub64(arg1[6], arg2[6], uint64(p521Uint1(x12)))
+	var x15 uint64
+	var x16 uint64
+	x15, x16 = bits.Sub64(arg1[7], arg2[7], uint64(p521Uint1(x14)))
+	var x17 uint64
+	var x18 uint64
+	x17, x18 = bits.Sub64(arg1[8], arg2[8], uint64(p521Uint1(x16)))
+	var x19 uint64
+	p521CmovznzU64(&x19, p521Uint1(x18), uint64(0x0), 0xffffffffffffffff)
+	var x20 uint64
+	var x21 uint64
+	x20, x21 = bits.Add64(x1, x19, uint64(0x0))
+	var x22 uint64
+	var x23 uint64
+	x22, x23 = bits.Add64(x3, x19, uint64(p521Uint1(x21)))
+	var x24 uint64
+	var x25 uint64
+	x24, x25 = bits.Add64(x5, x19, uint64(p521Uint1(x23)))
+	var x26 uint64
+	var x27 uint64
+	x26, x27 = bits.Add64(x7, x19, uint64(p521Uint1(x25)))
+	var x28 uint64
+	var x29 uint64
+	x28, x29 = bits.Add64(x9, x19, uint64(p521Uint1(x27)))
+	var x30 uint64
+	var x31 uint64
+	x30, x31 = bits.Add64(x11, x19, uint64(p521Uint1(x29)))
+	var x32 uint64
+	var x33 uint64
+	x32, x33 = bits.Add64(x13, x19, uint64(p521Uint1(x31)))
+	var x34 uint64
+	var x35 uint64
+	x34, x35 = bits.Add64(x15, x19, uint64(p521Uint1(x33)))
+	var x36 uint64
+	x36, _ = bits.Add64(x17, (x19 & 0x1ff), uint64(p521Uint1(x35)))
+	out1[0] = x20
+	out1[1] = x22
+	out1[2] = x24
+	out1[3] = x26
+	out1[4] = x28
+	out1[5] = x30
+	out1[6] = x32
+	out1[7] = x34
+	out1[8] = x36
+}
+
+// p521SetOne returns the field element one in the Montgomery domain.
+//
+// Postconditions:
+//
+//	eval (from_montgomery out1) mod m = 1 mod m
+//	0 ≤ eval out1 < m
+func p521SetOne(out1 *p521MontgomeryDomainFieldElement) {
+	out1[0] = 0x80000000000000
+	out1[1] = uint64(0x0)
+	out1[2] = uint64(0x0)
+	out1[3] = uint64(0x0)
+	out1[4] = uint64(0x0)
+	out1[5] = uint64(0x0)
+	out1[6] = uint64(0x0)
+	out1[7] = uint64(0x0)
+	out1[8] = uint64(0x0)
+}
+
+// p521FromMontgomery translates a field element out of the Montgomery domain.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//
+// Postconditions:
+//
+//	eval out1 mod m = (eval arg1 * ((2^64)⁻¹ mod m)^9) mod m
+//	0 ≤ eval out1 < m
+func p521FromMontgomery(out1 *p521NonMontgomeryDomainFieldElement, arg1 *p521MontgomeryDomainFieldElement) {
+	x1 := arg1[0]
+	var x2 uint64
+	var x3 uint64
+	x3, x2 = bits.Mul64(x1, 0x1ff)
+	var x4 uint64
+	var x5 uint64
+	x5, x4 = bits.Mul64(x1, 0xffffffffffffffff)
+	var x6 uint64
+	var x7 uint64
+	x7, x6 = bits.Mul64(x1, 0xffffffffffffffff)
+	var x8 uint64
+	var x9 uint64
+	x9, x8 = bits.Mul64(x1, 0xffffffffffffffff)
+	var x10 uint64
+	var x11 uint64
+	x11, x10 = bits.Mul64(x1, 0xffffffffffffffff)
+	var x12 uint64
+	var x13 uint64
+	x13, x12 = bits.Mul64(x1, 0xffffffffffffffff)
+	var x14 uint64
+	var x15 uint64
+	x15, x14 = bits.Mul64(x1, 0xffffffffffffffff)
+	var x16 uint64
+	var x17 uint64
+	x17, x16 = bits.Mul64(x1, 0xffffffffffffffff)
+	var x18 uint64
+	var x19 uint64
+	x19, x18 = bits.Mul64(x1, 0xffffffffffffffff)
+	var x20 uint64
+	var x21 uint64
+	x20, x21 = bits.Add64(x19, x16, uint64(0x0))
+	var x22 uint64
+	var x23 uint64
+	x22, x23 = bits.Add64(x17, x14, uint64(p521Uint1(x21)))
+	var x24 uint64
+	var x25 uint64
+	x24, x25 = bits.Add64(x15, x12, uint64(p521Uint1(x23)))
+	var x26 uint64
+	var x27 uint64
+	x26, x27 = bits.Add64(x13, x10, uint64(p521Uint1(x25)))
+	var x28 uint64
+	var x29 uint64
+	x28, x29 = bits.Add64(x11, x8, uint64(p521Uint1(x27)))
+	var x30 uint64
+	var x31 uint64
+	x30, x31 = bits.Add64(x9, x6, uint64(p521Uint1(x29)))
+	var x32 uint64
+	var x33 uint64
+	x32, x33 = bits.Add64(x7, x4, uint64(p521Uint1(x31)))
+	var x34 uint64
+	var x35 uint64
+	x34, x35 = bits.Add64(x5, x2, uint64(p521Uint1(x33)))
+	var x37 uint64
+	_, x37 = bits.Add64(x1, x18, uint64(0x0))
+	var x38 uint64
+	var x39 uint64
+	x38, x39 = bits.Add64(uint64(0x0), x20, uint64(p521Uint1(x37)))
+	var x40 uint64
+	var x41 uint64
+	x40, x41 = bits.Add64(uint64(0x0), x22, uint64(p521Uint1(x39)))
+	var x42 uint64
+	var x43 uint64
+	x42, x43 = bits.Add64(uint64(0x0), x24, uint64(p521Uint1(x41)))
+	var x44 uint64
+	var x45 uint64
+	x44, x45 = bits.Add64(uint64(0x0), x26, uint64(p521Uint1(x43)))
+	var x46 uint64
+	var x47 uint64
+	x46, x47 = bits.Add64(uint64(0x0), x28, uint64(p521Uint1(x45)))
+	var x48 uint64
+	var x49 uint64
+	x48, x49 = bits.Add64(uint64(0x0), x30, uint64(p521Uint1(x47)))
+	var x50 uint64
+	var x51 uint64
+	x50, x51 = bits.Add64(uint64(0x0), x32, uint64(p521Uint1(x49)))
+	var x52 uint64
+	var x53 uint64
+	x52, x53 = bits.Add64(uint64(0x0), x34, uint64(p521Uint1(x51)))
+	var x54 uint64
+	var x55 uint64
+	x54, x55 = bits.Add64(x38, arg1[1], uint64(0x0))
+	var x56 uint64
+	var x57 uint64
+	x56, x57 = bits.Add64(x40, uint64(0x0), uint64(p521Uint1(x55)))
+	var x58 uint64
+	var x59 uint64
+	x58, x59 = bits.Add64(x42, uint64(0x0), uint64(p521Uint1(x57)))
+	var x60 uint64
+	var x61 uint64
+	x60, x61 = bits.Add64(x44, uint64(0x0), uint64(p521Uint1(x59)))
+	var x62 uint64
+	var x63 uint64
+	x62, x63 = bits.Add64(x46, uint64(0x0), uint64(p521Uint1(x61)))
+	var x64 uint64
+	var x65 uint64
+	x64, x65 = bits.Add64(x48, uint64(0x0), uint64(p521Uint1(x63)))
+	var x66 uint64
+	var x67 uint64
+	x66, x67 = bits.Add64(x50, uint64(0x0), uint64(p521Uint1(x65)))
+	var x68 uint64
+	var x69 uint64
+	x68, x69 = bits.Add64(x52, uint64(0x0), uint64(p521Uint1(x67)))
+	var x70 uint64
+	var x71 uint64
+	x71, x70 = bits.Mul64(x54, 0x1ff)
+	var x72 uint64
+	var x73 uint64
+	x73, x72 = bits.Mul64(x54, 0xffffffffffffffff)
+	var x74 uint64
+	var x75 uint64
+	x75, x74 = bits.Mul64(x54, 0xffffffffffffffff)
+	var x76 uint64
+	var x77 uint64
+	x77, x76 = bits.Mul64(x54, 0xffffffffffffffff)
+	var x78 uint64
+	var x79 uint64
+	x79, x78 = bits.Mul64(x54, 0xffffffffffffffff)
+	var x80 uint64
+	var x81 uint64
+	x81, x80 = bits.Mul64(x54, 0xffffffffffffffff)
+	var x82 uint64
+	var x83 uint64
+	x83, x82 = bits.Mul64(x54, 0xffffffffffffffff)
+	var x84 uint64
+	var x85 uint64
+	x85, x84 = bits.Mul64(x54, 0xffffffffffffffff)
+	var x86 uint64
+	var x87 uint64
+	x87, x86 = bits.Mul64(x54, 0xffffffffffffffff)
+	var x88 uint64
+	var x89 uint64
+	x88, x89 = bits.Add64(x87, x84, uint64(0x0))
+	var x90 uint64
+	var x91 uint64
+	x90, x91 = bits.Add64(x85, x82, uint64(p521Uint1(x89)))
+	var x92 uint64
+	var x93 uint64
+	x92, x93 = bits.Add64(x83, x80, uint64(p521Uint1(x91)))
+	var x94 uint64
+	var x95 uint64
+	x94, x95 = bits.Add64(x81, x78, uint64(p521Uint1(x93)))
+	var x96 uint64
+	var x97 uint64
+	x96, x97 = bits.Add64(x79, x76, uint64(p521Uint1(x95)))
+	var x98 uint64
+	var x99 uint64
+	x98, x99 = bits.Add64(x77, x74, uint64(p521Uint1(x97)))
+	var x100 uint64
+	var x101 uint64
+	x100, x101 = bits.Add64(x75, x72, uint64(p521Uint1(x99)))
+	var x102 uint64
+	var x103 uint64
+	x102, x103 = bits.Add64(x73, x70, uint64(p521Uint1(x101)))
+	var x105 uint64
+	_, x105 = bits.Add64(x54, x86, uint64(0x0))
+	var x106 uint64
+	var x107 uint64
+	x106, x107 = bits.Add64(x56, x88, uint64(p521Uint1(x105)))
+	var x108 uint64
+	var x109 uint64
+	x108, x109 = bits.Add64(x58, x90, uint64(p521Uint1(x107)))
+	var x110 uint64
+	var x111 uint64
+	x110, x111 = bits.Add64(x60, x92, uint64(p521Uint1(x109)))
+	var x112 uint64
+	var x113 uint64
+	x112, x113 = bits.Add64(x62, x94, uint64(p521Uint1(x111)))
+	var x114 uint64
+	var x115 uint64
+	x114, x115 = bits.Add64(x64, x96, uint64(p521Uint1(x113)))
+	var x116 uint64
+	var x117 uint64
+	x116, x117 = bits.Add64(x66, x98, uint64(p521Uint1(x115)))
+	var x118 uint64
+	var x119 uint64
+	x118, x119 = bits.Add64(x68, x100, uint64(p521Uint1(x117)))
+	var x120 uint64
+	var x121 uint64
+	x120, x121 = bits.Add64((uint64(p521Uint1(x69)) + (uint64(p521Uint1(x53)) + (uint64(p521Uint1(x35)) + x3))), x102, uint64(p521Uint1(x119)))
+	var x122 uint64
+	var x123 uint64
+	x122, x123 = bits.Add64(x106, arg1[2], uint64(0x0))
+	var x124 uint64
+	var x125 uint64
+	x124, x125 = bits.Add64(x108, uint64(0x0), uint64(p521Uint1(x123)))
+	var x126 uint64
+	var x127 uint64
+	x126, x127 = bits.Add64(x110, uint64(0x0), uint64(p521Uint1(x125)))
+	var x128 uint64
+	var x129 uint64
+	x128, x129 = bits.Add64(x112, uint64(0x0), uint64(p521Uint1(x127)))
+	var x130 uint64
+	var x131 uint64
+	x130, x131 = bits.Add64(x114, uint64(0x0), uint64(p521Uint1(x129)))
+	var x132 uint64
+	var x133 uint64
+	x132, x133 = bits.Add64(x116, uint64(0x0), uint64(p521Uint1(x131)))
+	var x134 uint64
+	var x135 uint64
+	x134, x135 = bits.Add64(x118, uint64(0x0), uint64(p521Uint1(x133)))
+	var x136 uint64
+	var x137 uint64
+	x136, x137 = bits.Add64(x120, uint64(0x0), uint64(p521Uint1(x135)))
+	var x138 uint64
+	var x139 uint64
+	x139, x138 = bits.Mul64(x122, 0x1ff)
+	var x140 uint64
+	var x141 uint64
+	x141, x140 = bits.Mul64(x122, 0xffffffffffffffff)
+	var x142 uint64
+	var x143 uint64
+	x143, x142 = bits.Mul64(x122, 0xffffffffffffffff)
+	var x144 uint64
+	var x145 uint64
+	x145, x144 = bits.Mul64(x122, 0xffffffffffffffff)
+	var x146 uint64
+	var x147 uint64
+	x147, x146 = bits.Mul64(x122, 0xffffffffffffffff)
+	var x148 uint64
+	var x149 uint64
+	x149, x148 = bits.Mul64(x122, 0xffffffffffffffff)
+	var x150 uint64
+	var x151 uint64
+	x151, x150 = bits.Mul64(x122, 0xffffffffffffffff)
+	var x152 uint64
+	var x153 uint64
+	x153, x152 = bits.Mul64(x122, 0xffffffffffffffff)
+	var x154 uint64
+	var x155 uint64
+	x155, x154 = bits.Mul64(x122, 0xffffffffffffffff)
+	var x156 uint64
+	var x157 uint64
+	x156, x157 = bits.Add64(x155, x152, uint64(0x0))
+	var x158 uint64
+	var x159 uint64
+	x158, x159 = bits.Add64(x153, x150, uint64(p521Uint1(x157)))
+	var x160 uint64
+	var x161 uint64
+	x160, x161 = bits.Add64(x151, x148, uint64(p521Uint1(x159)))
+	var x162 uint64
+	var x163 uint64
+	x162, x163 = bits.Add64(x149, x146, uint64(p521Uint1(x161)))
+	var x164 uint64
+	var x165 uint64
+	x164, x165 = bits.Add64(x147, x144, uint64(p521Uint1(x163)))
+	var x166 uint64
+	var x167 uint64
+	x166, x167 = bits.Add64(x145, x142, uint64(p521Uint1(x165)))
+	var x168 uint64
+	var x169 uint64
+	x168, x169 = bits.Add64(x143, x140, uint64(p521Uint1(x167)))
+	var x170 uint64
+	var x171 uint64
+	x170, x171 = bits.Add64(x141, x138, uint64(p521Uint1(x169)))
+	var x173 uint64
+	_, x173 = bits.Add64(x122, x154, uint64(0x0))
+	var x174 uint64
+	var x175 uint64
+	x174, x175 = bits.Add64(x124, x156, uint64(p521Uint1(x173)))
+	var x176 uint64
+	var x177 uint64
+	x176, x177 = bits.Add64(x126, x158, uint64(p521Uint1(x175)))
+	var x178 uint64
+	var x179 uint64
+	x178, x179 = bits.Add64(x128, x160, uint64(p521Uint1(x177)))
+	var x180 uint64
+	var x181 uint64
+	x180, x181 = bits.Add64(x130, x162, uint64(p521Uint1(x179)))
+	var x182 uint64
+	var x183 uint64
+	x182, x183 = bits.Add64(x132, x164, uint64(p521Uint1(x181)))
+	var x184 uint64
+	var x185 uint64
+	x184, x185 = bits.Add64(x134, x166, uint64(p521Uint1(x183)))
+	var x186 uint64
+	var x187 uint64
+	x186, x187 = bits.Add64(x136, x168, uint64(p521Uint1(x185)))
+	var x188 uint64
+	var x189 uint64
+	x188, x189 = bits.Add64((uint64(p521Uint1(x137)) + (uint64(p521Uint1(x121)) + (uint64(p521Uint1(x103)) + x71))), x170, uint64(p521Uint1(x187)))
+	var x190 uint64
+	var x191 uint64
+	x190, x191 = bits.Add64(x174, arg1[3], uint64(0x0))
+	var x192 uint64
+	var x193 uint64
+	x192, x193 = bits.Add64(x176, uint64(0x0), uint64(p521Uint1(x191)))
+	var x194 uint64
+	var x195 uint64
+	x194, x195 = bits.Add64(x178, uint64(0x0), uint64(p521Uint1(x193)))
+	var x196 uint64
+	var x197 uint64
+	x196, x197 = bits.Add64(x180, uint64(0x0), uint64(p521Uint1(x195)))
+	var x198 uint64
+	var x199 uint64
+	x198, x199 = bits.Add64(x182, uint64(0x0), uint64(p521Uint1(x197)))
+	var x200 uint64
+	var x201 uint64
+	x200, x201 = bits.Add64(x184, uint64(0x0), uint64(p521Uint1(x199)))
+	var x202 uint64
+	var x203 uint64
+	x202, x203 = bits.Add64(x186, uint64(0x0), uint64(p521Uint1(x201)))
+	var x204 uint64
+	var x205 uint64
+	x204, x205 = bits.Add64(x188, uint64(0x0), uint64(p521Uint1(x203)))
+	var x206 uint64
+	var x207 uint64
+	x207, x206 = bits.Mul64(x190, 0x1ff)
+	var x208 uint64
+	var x209 uint64
+	x209, x208 = bits.Mul64(x190, 0xffffffffffffffff)
+	var x210 uint64
+	var x211 uint64
+	x211, x210 = bits.Mul64(x190, 0xffffffffffffffff)
+	var x212 uint64
+	var x213 uint64
+	x213, x212 = bits.Mul64(x190, 0xffffffffffffffff)
+	var x214 uint64
+	var x215 uint64
+	x215, x214 = bits.Mul64(x190, 0xffffffffffffffff)
+	var x216 uint64
+	var x217 uint64
+	x217, x216 = bits.Mul64(x190, 0xffffffffffffffff)
+	var x218 uint64
+	var x219 uint64
+	x219, x218 = bits.Mul64(x190, 0xffffffffffffffff)
+	var x220 uint64
+	var x221 uint64
+	x221, x220 = bits.Mul64(x190, 0xffffffffffffffff)
+	var x222 uint64
+	var x223 uint64
+	x223, x222 = bits.Mul64(x190, 0xffffffffffffffff)
+	var x224 uint64
+	var x225 uint64
+	x224, x225 = bits.Add64(x223, x220, uint64(0x0))
+	var x226 uint64
+	var x227 uint64
+	x226, x227 = bits.Add64(x221, x218, uint64(p521Uint1(x225)))
+	var x228 uint64
+	var x229 uint64
+	x228, x229 = bits.Add64(x219, x216, uint64(p521Uint1(x227)))
+	var x230 uint64
+	var x231 uint64
+	x230, x231 = bits.Add64(x217, x214, uint64(p521Uint1(x229)))
+	var x232 uint64
+	var x233 uint64
+	x232, x233 = bits.Add64(x215, x212, uint64(p521Uint1(x231)))
+	var x234 uint64
+	var x235 uint64
+	x234, x235 = bits.Add64(x213, x210, uint64(p521Uint1(x233)))
+	var x236 uint64
+	var x237 uint64
+	x236, x237 = bits.Add64(x211, x208, uint64(p521Uint1(x235)))
+	var x238 uint64
+	var x239 uint64
+	x238, x239 = bits.Add64(x209, x206, uint64(p521Uint1(x237)))
+	var x241 uint64
+	_, x241 = bits.Add64(x190, x222, uint64(0x0))
+	var x242 uint64
+	var x243 uint64
+	x242, x243 = bits.Add64(x192, x224, uint64(p521Uint1(x241)))
+	var x244 uint64
+	var x245 uint64
+	x244, x245 = bits.Add64(x194, x226, uint64(p521Uint1(x243)))
+	var x246 uint64
+	var x247 uint64
+	x246, x247 = bits.Add64(x196, x228, uint64(p521Uint1(x245)))
+	var x248 uint64
+	var x249 uint64
+	x248, x249 = bits.Add64(x198, x230, uint64(p521Uint1(x247)))
+	var x250 uint64
+	var x251 uint64
+	x250, x251 = bits.Add64(x200, x232, uint64(p521Uint1(x249)))
+	var x252 uint64
+	var x253 uint64
+	x252, x253 = bits.Add64(x202, x234, uint64(p521Uint1(x251)))
+	var x254 uint64
+	var x255 uint64
+	x254, x255 = bits.Add64(x204, x236, uint64(p521Uint1(x253)))
+	var x256 uint64
+	var x257 uint64
+	x256, x257 = bits.Add64((uint64(p521Uint1(x205)) + (uint64(p521Uint1(x189)) + (uint64(p521Uint1(x171)) + x139))), x238, uint64(p521Uint1(x255)))
+	var x258 uint64
+	var x259 uint64
+	x258, x259 = bits.Add64(x242, arg1[4], uint64(0x0))
+	var x260 uint64
+	var x261 uint64
+	x260, x261 = bits.Add64(x244, uint64(0x0), uint64(p521Uint1(x259)))
+	var x262 uint64
+	var x263 uint64
+	x262, x263 = bits.Add64(x246, uint64(0x0), uint64(p521Uint1(x261)))
+	var x264 uint64
+	var x265 uint64
+	x264, x265 = bits.Add64(x248, uint64(0x0), uint64(p521Uint1(x263)))
+	var x266 uint64
+	var x267 uint64
+	x266, x267 = bits.Add64(x250, uint64(0x0), uint64(p521Uint1(x265)))
+	var x268 uint64
+	var x269 uint64
+	x268, x269 = bits.Add64(x252, uint64(0x0), uint64(p521Uint1(x267)))
+	var x270 uint64
+	var x271 uint64
+	x270, x271 = bits.Add64(x254, uint64(0x0), uint64(p521Uint1(x269)))
+	var x272 uint64
+	var x273 uint64
+	x272, x273 = bits.Add64(x256, uint64(0x0), uint64(p521Uint1(x271)))
+	var x274 uint64
+	var x275 uint64
+	x275, x274 = bits.Mul64(x258, 0x1ff)
+	var x276 uint64
+	var x277 uint64
+	x277, x276 = bits.Mul64(x258, 0xffffffffffffffff)
+	var x278 uint64
+	var x279 uint64
+	x279, x278 = bits.Mul64(x258, 0xffffffffffffffff)
+	var x280 uint64
+	var x281 uint64
+	x281, x280 = bits.Mul64(x258, 0xffffffffffffffff)
+	var x282 uint64
+	var x283 uint64
+	x283, x282 = bits.Mul64(x258, 0xffffffffffffffff)
+	var x284 uint64
+	var x285 uint64
+	x285, x284 = bits.Mul64(x258, 0xffffffffffffffff)
+	var x286 uint64
+	var x287 uint64
+	x287, x286 = bits.Mul64(x258, 0xffffffffffffffff)
+	var x288 uint64
+	var x289 uint64
+	x289, x288 = bits.Mul64(x258, 0xffffffffffffffff)
+	var x290 uint64
+	var x291 uint64
+	x291, x290 = bits.Mul64(x258, 0xffffffffffffffff)
+	var x292 uint64
+	var x293 uint64
+	x292, x293 = bits.Add64(x291, x288, uint64(0x0))
+	var x294 uint64
+	var x295 uint64
+	x294, x295 = bits.Add64(x289, x286, uint64(p521Uint1(x293)))
+	var x296 uint64
+	var x297 uint64
+	x296, x297 = bits.Add64(x287, x284, uint64(p521Uint1(x295)))
+	var x298 uint64
+	var x299 uint64
+	x298, x299 = bits.Add64(x285, x282, uint64(p521Uint1(x297)))
+	var x300 uint64
+	var x301 uint64
+	x300, x301 = bits.Add64(x283, x280, uint64(p521Uint1(x299)))
+	var x302 uint64
+	var x303 uint64
+	x302, x303 = bits.Add64(x281, x278, uint64(p521Uint1(x301)))
+	var x304 uint64
+	var x305 uint64
+	x304, x305 = bits.Add64(x279, x276, uint64(p521Uint1(x303)))
+	var x306 uint64
+	var x307 uint64
+	x306, x307 = bits.Add64(x277, x274, uint64(p521Uint1(x305)))
+	var x309 uint64
+	_, x309 = bits.Add64(x258, x290, uint64(0x0))
+	var x310 uint64
+	var x311 uint64
+	x310, x311 = bits.Add64(x260, x292, uint64(p521Uint1(x309)))
+	var x312 uint64
+	var x313 uint64
+	x312, x313 = bits.Add64(x262, x294, uint64(p521Uint1(x311)))
+	var x314 uint64
+	var x315 uint64
+	x314, x315 = bits.Add64(x264, x296, uint64(p521Uint1(x313)))
+	var x316 uint64
+	var x317 uint64
+	x316, x317 = bits.Add64(x266, x298, uint64(p521Uint1(x315)))
+	var x318 uint64
+	var x319 uint64
+	x318, x319 = bits.Add64(x268, x300, uint64(p521Uint1(x317)))
+	var x320 uint64
+	var x321 uint64
+	x320, x321 = bits.Add64(x270, x302, uint64(p521Uint1(x319)))
+	var x322 uint64
+	var x323 uint64
+	x322, x323 = bits.Add64(x272, x304, uint64(p521Uint1(x321)))
+	var x324 uint64
+	var x325 uint64
+	x324, x325 = bits.Add64((uint64(p521Uint1(x273)) + (uint64(p521Uint1(x257)) + (uint64(p521Uint1(x239)) + x207))), x306, uint64(p521Uint1(x323)))
+	var x326 uint64
+	var x327 uint64
+	x326, x327 = bits.Add64(x310, arg1[5], uint64(0x0))
+	var x328 uint64
+	var x329 uint64
+	x328, x329 = bits.Add64(x312, uint64(0x0), uint64(p521Uint1(x327)))
+	var x330 uint64
+	var x331 uint64
+	x330, x331 = bits.Add64(x314, uint64(0x0), uint64(p521Uint1(x329)))
+	var x332 uint64
+	var x333 uint64
+	x332, x333 = bits.Add64(x316, uint64(0x0), uint64(p521Uint1(x331)))
+	var x334 uint64
+	var x335 uint64
+	x334, x335 = bits.Add64(x318, uint64(0x0), uint64(p521Uint1(x333)))
+	var x336 uint64
+	var x337 uint64
+	x336, x337 = bits.Add64(x320, uint64(0x0), uint64(p521Uint1(x335)))
+	var x338 uint64
+	var x339 uint64
+	x338, x339 = bits.Add64(x322, uint64(0x0), uint64(p521Uint1(x337)))
+	var x340 uint64
+	var x341 uint64
+	x340, x341 = bits.Add64(x324, uint64(0x0), uint64(p521Uint1(x339)))
+	var x342 uint64
+	var x343 uint64
+	x343, x342 = bits.Mul64(x326, 0x1ff)
+	var x344 uint64
+	var x345 uint64
+	x345, x344 = bits.Mul64(x326, 0xffffffffffffffff)
+	var x346 uint64
+	var x347 uint64
+	x347, x346 = bits.Mul64(x326, 0xffffffffffffffff)
+	var x348 uint64
+	var x349 uint64
+	x349, x348 = bits.Mul64(x326, 0xffffffffffffffff)
+	var x350 uint64
+	var x351 uint64
+	x351, x350 = bits.Mul64(x326, 0xffffffffffffffff)
+	var x352 uint64
+	var x353 uint64
+	x353, x352 = bits.Mul64(x326, 0xffffffffffffffff)
+	var x354 uint64
+	var x355 uint64
+	x355, x354 = bits.Mul64(x326, 0xffffffffffffffff)
+	var x356 uint64
+	var x357 uint64
+	x357, x356 = bits.Mul64(x326, 0xffffffffffffffff)
+	var x358 uint64
+	var x359 uint64
+	x359, x358 = bits.Mul64(x326, 0xffffffffffffffff)
+	var x360 uint64
+	var x361 uint64
+	x360, x361 = bits.Add64(x359, x356, uint64(0x0))
+	var x362 uint64
+	var x363 uint64
+	x362, x363 = bits.Add64(x357, x354, uint64(p521Uint1(x361)))
+	var x364 uint64
+	var x365 uint64
+	x364, x365 = bits.Add64(x355, x352, uint64(p521Uint1(x363)))
+	var x366 uint64
+	var x367 uint64
+	x366, x367 = bits.Add64(x353, x350, uint64(p521Uint1(x365)))
+	var x368 uint64
+	var x369 uint64
+	x368, x369 = bits.Add64(x351, x348, uint64(p521Uint1(x367)))
+	var x370 uint64
+	var x371 uint64
+	x370, x371 = bits.Add64(x349, x346, uint64(p521Uint1(x369)))
+	var x372 uint64
+	var x373 uint64
+	x372, x373 = bits.Add64(x347, x344, uint64(p521Uint1(x371)))
+	var x374 uint64
+	var x375 uint64
+	x374, x375 = bits.Add64(x345, x342, uint64(p521Uint1(x373)))
+	var x377 uint64
+	_, x377 = bits.Add64(x326, x358, uint64(0x0))
+	var x378 uint64
+	var x379 uint64
+	x378, x379 = bits.Add64(x328, x360, uint64(p521Uint1(x377)))
+	var x380 uint64
+	var x381 uint64
+	x380, x381 = bits.Add64(x330, x362, uint64(p521Uint1(x379)))
+	var x382 uint64
+	var x383 uint64
+	x382, x383 = bits.Add64(x332, x364, uint64(p521Uint1(x381)))
+	var x384 uint64
+	var x385 uint64
+	x384, x385 = bits.Add64(x334, x366, uint64(p521Uint1(x383)))
+	var x386 uint64
+	var x387 uint64
+	x386, x387 = bits.Add64(x336, x368, uint64(p521Uint1(x385)))
+	var x388 uint64
+	var x389 uint64
+	x388, x389 = bits.Add64(x338, x370, uint64(p521Uint1(x387)))
+	var x390 uint64
+	var x391 uint64
+	x390, x391 = bits.Add64(x340, x372, uint64(p521Uint1(x389)))
+	var x392 uint64
+	var x393 uint64
+	x392, x393 = bits.Add64((uint64(p521Uint1(x341)) + (uint64(p521Uint1(x325)) + (uint64(p521Uint1(x307)) + x275))), x374, uint64(p521Uint1(x391)))
+	var x394 uint64
+	var x395 uint64
+	x394, x395 = bits.Add64(x378, arg1[6], uint64(0x0))
+	var x396 uint64
+	var x397 uint64
+	x396, x397 = bits.Add64(x380, uint64(0x0), uint64(p521Uint1(x395)))
+	var x398 uint64
+	var x399 uint64
+	x398, x399 = bits.Add64(x382, uint64(0x0), uint64(p521Uint1(x397)))
+	var x400 uint64
+	var x401 uint64
+	x400, x401 = bits.Add64(x384, uint64(0x0), uint64(p521Uint1(x399)))
+	var x402 uint64
+	var x403 uint64
+	x402, x403 = bits.Add64(x386, uint64(0x0), uint64(p521Uint1(x401)))
+	var x404 uint64
+	var x405 uint64
+	x404, x405 = bits.Add64(x388, uint64(0x0), uint64(p521Uint1(x403)))
+	var x406 uint64
+	var x407 uint64
+	x406, x407 = bits.Add64(x390, uint64(0x0), uint64(p521Uint1(x405)))
+	var x408 uint64
+	var x409 uint64
+	x408, x409 = bits.Add64(x392, uint64(0x0), uint64(p521Uint1(x407)))
+	var x410 uint64
+	var x411 uint64
+	x411, x410 = bits.Mul64(x394, 0x1ff)
+	var x412 uint64
+	var x413 uint64
+	x413, x412 = bits.Mul64(x394, 0xffffffffffffffff)
+	var x414 uint64
+	var x415 uint64
+	x415, x414 = bits.Mul64(x394, 0xffffffffffffffff)
+	var x416 uint64
+	var x417 uint64
+	x417, x416 = bits.Mul64(x394, 0xffffffffffffffff)
+	var x418 uint64
+	var x419 uint64
+	x419, x418 = bits.Mul64(x394, 0xffffffffffffffff)
+	var x420 uint64
+	var x421 uint64
+	x421, x420 = bits.Mul64(x394, 0xffffffffffffffff)
+	var x422 uint64
+	var x423 uint64
+	x423, x422 = bits.Mul64(x394, 0xffffffffffffffff)
+	var x424 uint64
+	var x425 uint64
+	x425, x424 = bits.Mul64(x394, 0xffffffffffffffff)
+	var x426 uint64
+	var x427 uint64
+	x427, x426 = bits.Mul64(x394, 0xffffffffffffffff)
+	var x428 uint64
+	var x429 uint64
+	x428, x429 = bits.Add64(x427, x424, uint64(0x0))
+	var x430 uint64
+	var x431 uint64
+	x430, x431 = bits.Add64(x425, x422, uint64(p521Uint1(x429)))
+	var x432 uint64
+	var x433 uint64
+	x432, x433 = bits.Add64(x423, x420, uint64(p521Uint1(x431)))
+	var x434 uint64
+	var x435 uint64
+	x434, x435 = bits.Add64(x421, x418, uint64(p521Uint1(x433)))
+	var x436 uint64
+	var x437 uint64
+	x436, x437 = bits.Add64(x419, x416, uint64(p521Uint1(x435)))
+	var x438 uint64
+	var x439 uint64
+	x438, x439 = bits.Add64(x417, x414, uint64(p521Uint1(x437)))
+	var x440 uint64
+	var x441 uint64
+	x440, x441 = bits.Add64(x415, x412, uint64(p521Uint1(x439)))
+	var x442 uint64
+	var x443 uint64
+	x442, x443 = bits.Add64(x413, x410, uint64(p521Uint1(x441)))
+	var x445 uint64
+	_, x445 = bits.Add64(x394, x426, uint64(0x0))
+	var x446 uint64
+	var x447 uint64
+	x446, x447 = bits.Add64(x396, x428, uint64(p521Uint1(x445)))
+	var x448 uint64
+	var x449 uint64
+	x448, x449 = bits.Add64(x398, x430, uint64(p521Uint1(x447)))
+	var x450 uint64
+	var x451 uint64
+	x450, x451 = bits.Add64(x400, x432, uint64(p521Uint1(x449)))
+	var x452 uint64
+	var x453 uint64
+	x452, x453 = bits.Add64(x402, x434, uint64(p521Uint1(x451)))
+	var x454 uint64
+	var x455 uint64
+	x454, x455 = bits.Add64(x404, x436, uint64(p521Uint1(x453)))
+	var x456 uint64
+	var x457 uint64
+	x456, x457 = bits.Add64(x406, x438, uint64(p521Uint1(x455)))
+	var x458 uint64
+	var x459 uint64
+	x458, x459 = bits.Add64(x408, x440, uint64(p521Uint1(x457)))
+	var x460 uint64
+	var x461 uint64
+	x460, x461 = bits.Add64((uint64(p521Uint1(x409)) + (uint64(p521Uint1(x393)) + (uint64(p521Uint1(x375)) + x343))), x442, uint64(p521Uint1(x459)))
+	var x462 uint64
+	var x463 uint64
+	x462, x463 = bits.Add64(x446, arg1[7], uint64(0x0))
+	var x464 uint64
+	var x465 uint64
+	x464, x465 = bits.Add64(x448, uint64(0x0), uint64(p521Uint1(x463)))
+	var x466 uint64
+	var x467 uint64
+	x466, x467 = bits.Add64(x450, uint64(0x0), uint64(p521Uint1(x465)))
+	var x468 uint64
+	var x469 uint64
+	x468, x469 = bits.Add64(x452, uint64(0x0), uint64(p521Uint1(x467)))
+	var x470 uint64
+	var x471 uint64
+	x470, x471 = bits.Add64(x454, uint64(0x0), uint64(p521Uint1(x469)))
+	var x472 uint64
+	var x473 uint64
+	x472, x473 = bits.Add64(x456, uint64(0x0), uint64(p521Uint1(x471)))
+	var x474 uint64
+	var x475 uint64
+	x474, x475 = bits.Add64(x458, uint64(0x0), uint64(p521Uint1(x473)))
+	var x476 uint64
+	var x477 uint64
+	x476, x477 = bits.Add64(x460, uint64(0x0), uint64(p521Uint1(x475)))
+	var x478 uint64
+	var x479 uint64
+	x479, x478 = bits.Mul64(x462, 0x1ff)
+	var x480 uint64
+	var x481 uint64
+	x481, x480 = bits.Mul64(x462, 0xffffffffffffffff)
+	var x482 uint64
+	var x483 uint64
+	x483, x482 = bits.Mul64(x462, 0xffffffffffffffff)
+	var x484 uint64
+	var x485 uint64
+	x485, x484 = bits.Mul64(x462, 0xffffffffffffffff)
+	var x486 uint64
+	var x487 uint64
+	x487, x486 = bits.Mul64(x462, 0xffffffffffffffff)
+	var x488 uint64
+	var x489 uint64
+	x489, x488 = bits.Mul64(x462, 0xffffffffffffffff)
+	var x490 uint64
+	var x491 uint64
+	x491, x490 = bits.Mul64(x462, 0xffffffffffffffff)
+	var x492 uint64
+	var x493 uint64
+	x493, x492 = bits.Mul64(x462, 0xffffffffffffffff)
+	var x494 uint64
+	var x495 uint64
+	x495, x494 = bits.Mul64(x462, 0xffffffffffffffff)
+	var x496 uint64
+	var x497 uint64
+	x496, x497 = bits.Add64(x495, x492, uint64(0x0))
+	var x498 uint64
+	var x499 uint64
+	x498, x499 = bits.Add64(x493, x490, uint64(p521Uint1(x497)))
+	var x500 uint64
+	var x501 uint64
+	x500, x501 = bits.Add64(x491, x488, uint64(p521Uint1(x499)))
+	var x502 uint64
+	var x503 uint64
+	x502, x503 = bits.Add64(x489, x486, uint64(p521Uint1(x501)))
+	var x504 uint64
+	var x505 uint64
+	x504, x505 = bits.Add64(x487, x484, uint64(p521Uint1(x503)))
+	var x506 uint64
+	var x507 uint64
+	x506, x507 = bits.Add64(x485, x482, uint64(p521Uint1(x505)))
+	var x508 uint64
+	var x509 uint64
+	x508, x509 = bits.Add64(x483, x480, uint64(p521Uint1(x507)))
+	var x510 uint64
+	var x511 uint64
+	x510, x511 = bits.Add64(x481, x478, uint64(p521Uint1(x509)))
+	var x513 uint64
+	_, x513 = bits.Add64(x462, x494, uint64(0x0))
+	var x514 uint64
+	var x515 uint64
+	x514, x515 = bits.Add64(x464, x496, uint64(p521Uint1(x513)))
+	var x516 uint64
+	var x517 uint64
+	x516, x517 = bits.Add64(x466, x498, uint64(p521Uint1(x515)))
+	var x518 uint64
+	var x519 uint64
+	x518, x519 = bits.Add64(x468, x500, uint64(p521Uint1(x517)))
+	var x520 uint64
+	var x521 uint64
+	x520, x521 = bits.Add64(x470, x502, uint64(p521Uint1(x519)))
+	var x522 uint64
+	var x523 uint64
+	x522, x523 = bits.Add64(x472, x504, uint64(p521Uint1(x521)))
+	var x524 uint64
+	var x525 uint64
+	x524, x525 = bits.Add64(x474, x506, uint64(p521Uint1(x523)))
+	var x526 uint64
+	var x527 uint64
+	x526, x527 = bits.Add64(x476, x508, uint64(p521Uint1(x525)))
+	var x528 uint64
+	var x529 uint64
+	x528, x529 = bits.Add64((uint64(p521Uint1(x477)) + (uint64(p521Uint1(x461)) + (uint64(p521Uint1(x443)) + x411))), x510, uint64(p521Uint1(x527)))
+	var x530 uint64
+	var x531 uint64
+	x530, x531 = bits.Add64(x514, arg1[8], uint64(0x0))
+	var x532 uint64
+	var x533 uint64
+	x532, x533 = bits.Add64(x516, uint64(0x0), uint64(p521Uint1(x531)))
+	var x534 uint64
+	var x535 uint64
+	x534, x535 = bits.Add64(x518, uint64(0x0), uint64(p521Uint1(x533)))
+	var x536 uint64
+	var x537 uint64
+	x536, x537 = bits.Add64(x520, uint64(0x0), uint64(p521Uint1(x535)))
+	var x538 uint64
+	var x539 uint64
+	x538, x539 = bits.Add64(x522, uint64(0x0), uint64(p521Uint1(x537)))
+	var x540 uint64
+	var x541 uint64
+	x540, x541 = bits.Add64(x524, uint64(0x0), uint64(p521Uint1(x539)))
+	var x542 uint64
+	var x543 uint64
+	x542, x543 = bits.Add64(x526, uint64(0x0), uint64(p521Uint1(x541)))
+	var x544 uint64
+	var x545 uint64
+	x544, x545 = bits.Add64(x528, uint64(0x0), uint64(p521Uint1(x543)))
+	var x546 uint64
+	var x547 uint64
+	x547, x546 = bits.Mul64(x530, 0x1ff)
+	var x548 uint64
+	var x549 uint64
+	x549, x548 = bits.Mul64(x530, 0xffffffffffffffff)
+	var x550 uint64
+	var x551 uint64
+	x551, x550 = bits.Mul64(x530, 0xffffffffffffffff)
+	var x552 uint64
+	var x553 uint64
+	x553, x552 = bits.Mul64(x530, 0xffffffffffffffff)
+	var x554 uint64
+	var x555 uint64
+	x555, x554 = bits.Mul64(x530, 0xffffffffffffffff)
+	var x556 uint64
+	var x557 uint64
+	x557, x556 = bits.Mul64(x530, 0xffffffffffffffff)
+	var x558 uint64
+	var x559 uint64
+	x559, x558 = bits.Mul64(x530, 0xffffffffffffffff)
+	var x560 uint64
+	var x561 uint64
+	x561, x560 = bits.Mul64(x530, 0xffffffffffffffff)
+	var x562 uint64
+	var x563 uint64
+	x563, x562 = bits.Mul64(x530, 0xffffffffffffffff)
+	var x564 uint64
+	var x565 uint64
+	x564, x565 = bits.Add64(x563, x560, uint64(0x0))
+	var x566 uint64
+	var x567 uint64
+	x566, x567 = bits.Add64(x561, x558, uint64(p521Uint1(x565)))
+	var x568 uint64
+	var x569 uint64
+	x568, x569 = bits.Add64(x559, x556, uint64(p521Uint1(x567)))
+	var x570 uint64
+	var x571 uint64
+	x570, x571 = bits.Add64(x557, x554, uint64(p521Uint1(x569)))
+	var x572 uint64
+	var x573 uint64
+	x572, x573 = bits.Add64(x555, x552, uint64(p521Uint1(x571)))
+	var x574 uint64
+	var x575 uint64
+	x574, x575 = bits.Add64(x553, x550, uint64(p521Uint1(x573)))
+	var x576 uint64
+	var x577 uint64
+	x576, x577 = bits.Add64(x551, x548, uint64(p521Uint1(x575)))
+	var x578 uint64
+	var x579 uint64
+	x578, x579 = bits.Add64(x549, x546, uint64(p521Uint1(x577)))
+	var x581 uint64
+	_, x581 = bits.Add64(x530, x562, uint64(0x0))
+	var x582 uint64
+	var x583 uint64
+	x582, x583 = bits.Add64(x532, x564, uint64(p521Uint1(x581)))
+	var x584 uint64
+	var x585 uint64
+	x584, x585 = bits.Add64(x534, x566, uint64(p521Uint1(x583)))
+	var x586 uint64
+	var x587 uint64
+	x586, x587 = bits.Add64(x536, x568, uint64(p521Uint1(x585)))
+	var x588 uint64
+	var x589 uint64
+	x588, x589 = bits.Add64(x538, x570, uint64(p521Uint1(x587)))
+	var x590 uint64
+	var x591 uint64
+	x590, x591 = bits.Add64(x540, x572, uint64(p521Uint1(x589)))
+	var x592 uint64
+	var x593 uint64
+	x592, x593 = bits.Add64(x542, x574, uint64(p521Uint1(x591)))
+	var x594 uint64
+	var x595 uint64
+	x594, x595 = bits.Add64(x544, x576, uint64(p521Uint1(x593)))
+	var x596 uint64
+	var x597 uint64
+	x596, x597 = bits.Add64((uint64(p521Uint1(x545)) + (uint64(p521Uint1(x529)) + (uint64(p521Uint1(x511)) + x479))), x578, uint64(p521Uint1(x595)))
+	x598 := (uint64(p521Uint1(x597)) + (uint64(p521Uint1(x579)) + x547))
+	var x599 uint64
+	var x600 uint64
+	x599, x600 = bits.Sub64(x582, 0xffffffffffffffff, uint64(0x0))
+	var x601 uint64
+	var x602 uint64
+	x601, x602 = bits.Sub64(x584, 0xffffffffffffffff, uint64(p521Uint1(x600)))
+	var x603 uint64
+	var x604 uint64
+	x603, x604 = bits.Sub64(x586, 0xffffffffffffffff, uint64(p521Uint1(x602)))
+	var x605 uint64
+	var x606 uint64
+	x605, x606 = bits.Sub64(x588, 0xffffffffffffffff, uint64(p521Uint1(x604)))
+	var x607 uint64
+	var x608 uint64
+	x607, x608 = bits.Sub64(x590, 0xffffffffffffffff, uint64(p521Uint1(x606)))
+	var x609 uint64
+	var x610 uint64
+	x609, x610 = bits.Sub64(x592, 0xffffffffffffffff, uint64(p521Uint1(x608)))
+	var x611 uint64
+	var x612 uint64
+	x611, x612 = bits.Sub64(x594, 0xffffffffffffffff, uint64(p521Uint1(x610)))
+	var x613 uint64
+	var x614 uint64
+	x613, x614 = bits.Sub64(x596, 0xffffffffffffffff, uint64(p521Uint1(x612)))
+	var x615 uint64
+	var x616 uint64
+	x615, x616 = bits.Sub64(x598, 0x1ff, uint64(p521Uint1(x614)))
+	var x618 uint64
+	_, x618 = bits.Sub64(uint64(0x0), uint64(0x0), uint64(p521Uint1(x616)))
+	var x619 uint64
+	p521CmovznzU64(&x619, p521Uint1(x618), x599, x582)
+	var x620 uint64
+	p521CmovznzU64(&x620, p521Uint1(x618), x601, x584)
+	var x621 uint64
+	p521CmovznzU64(&x621, p521Uint1(x618), x603, x586)
+	var x622 uint64
+	p521CmovznzU64(&x622, p521Uint1(x618), x605, x588)
+	var x623 uint64
+	p521CmovznzU64(&x623, p521Uint1(x618), x607, x590)
+	var x624 uint64
+	p521CmovznzU64(&x624, p521Uint1(x618), x609, x592)
+	var x625 uint64
+	p521CmovznzU64(&x625, p521Uint1(x618), x611, x594)
+	var x626 uint64
+	p521CmovznzU64(&x626, p521Uint1(x618), x613, x596)
+	var x627 uint64
+	p521CmovznzU64(&x627, p521Uint1(x618), x615, x598)
+	out1[0] = x619
+	out1[1] = x620
+	out1[2] = x621
+	out1[3] = x622
+	out1[4] = x623
+	out1[5] = x624
+	out1[6] = x625
+	out1[7] = x626
+	out1[8] = x627
+}
+
+// p521ToMontgomery translates a field element into the Montgomery domain.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//
+// Postconditions:
+//
+//	eval (from_montgomery out1) mod m = eval arg1 mod m
+//	0 ≤ eval out1 < m
+func p521ToMontgomery(out1 *p521MontgomeryDomainFieldElement, arg1 *p521NonMontgomeryDomainFieldElement) {
+	var x1 uint64
+	var x2 uint64
+	x2, x1 = bits.Mul64(arg1[0], 0x400000000000)
+	var x3 uint64
+	var x4 uint64
+	x4, x3 = bits.Mul64(arg1[1], 0x400000000000)
+	var x5 uint64
+	var x6 uint64
+	x5, x6 = bits.Add64(x2, x3, uint64(0x0))
+	var x7 uint64
+	var x8 uint64
+	x8, x7 = bits.Mul64(x1, 0x1ff)
+	var x9 uint64
+	var x10 uint64
+	x10, x9 = bits.Mul64(x1, 0xffffffffffffffff)
+	var x11 uint64
+	var x12 uint64
+	x12, x11 = bits.Mul64(x1, 0xffffffffffffffff)
+	var x13 uint64
+	var x14 uint64
+	x14, x13 = bits.Mul64(x1, 0xffffffffffffffff)
+	var x15 uint64
+	var x16 uint64
+	x16, x15 = bits.Mul64(x1, 0xffffffffffffffff)
+	var x17 uint64
+	var x18 uint64
+	x18, x17 = bits.Mul64(x1, 0xffffffffffffffff)
+	var x19 uint64
+	var x20 uint64
+	x20, x19 = bits.Mul64(x1, 0xffffffffffffffff)
+	var x21 uint64
+	var x22 uint64
+	x22, x21 = bits.Mul64(x1, 0xffffffffffffffff)
+	var x23 uint64
+	var x24 uint64
+	x24, x23 = bits.Mul64(x1, 0xffffffffffffffff)
+	var x25 uint64
+	var x26 uint64
+	x25, x26 = bits.Add64(x24, x21, uint64(0x0))
+	var x27 uint64
+	var x28 uint64
+	x27, x28 = bits.Add64(x22, x19, uint64(p521Uint1(x26)))
+	var x29 uint64
+	var x30 uint64
+	x29, x30 = bits.Add64(x20, x17, uint64(p521Uint1(x28)))
+	var x31 uint64
+	var x32 uint64
+	x31, x32 = bits.Add64(x18, x15, uint64(p521Uint1(x30)))
+	var x33 uint64
+	var x34 uint64
+	x33, x34 = bits.Add64(x16, x13, uint64(p521Uint1(x32)))
+	var x35 uint64
+	var x36 uint64
+	x35, x36 = bits.Add64(x14, x11, uint64(p521Uint1(x34)))
+	var x37 uint64
+	var x38 uint64
+	x37, x38 = bits.Add64(x12, x9, uint64(p521Uint1(x36)))
+	var x39 uint64
+	var x40 uint64
+	x39, x40 = bits.Add64(x10, x7, uint64(p521Uint1(x38)))
+	var x42 uint64
+	_, x42 = bits.Add64(x1, x23, uint64(0x0))
+	var x43 uint64
+	var x44 uint64
+	x43, x44 = bits.Add64(x5, x25, uint64(p521Uint1(x42)))
+	var x45 uint64
+	var x46 uint64
+	x45, x46 = bits.Add64((uint64(p521Uint1(x6)) + x4), x27, uint64(p521Uint1(x44)))
+	var x47 uint64
+	var x48 uint64
+	x47, x48 = bits.Add64(uint64(0x0), x29, uint64(p521Uint1(x46)))
+	var x49 uint64
+	var x50 uint64
+	x49, x50 = bits.Add64(uint64(0x0), x31, uint64(p521Uint1(x48)))
+	var x51 uint64
+	var x52 uint64
+	x51, x52 = bits.Add64(uint64(0x0), x33, uint64(p521Uint1(x50)))
+	var x53 uint64
+	var x54 uint64
+	x53, x54 = bits.Add64(uint64(0x0), x35, uint64(p521Uint1(x52)))
+	var x55 uint64
+	var x56 uint64
+	x55, x56 = bits.Add64(uint64(0x0), x37, uint64(p521Uint1(x54)))
+	var x57 uint64
+	var x58 uint64
+	x57, x58 = bits.Add64(uint64(0x0), x39, uint64(p521Uint1(x56)))
+	var x59 uint64
+	var x60 uint64
+	x60, x59 = bits.Mul64(arg1[2], 0x400000000000)
+	var x61 uint64
+	var x62 uint64
+	x61, x62 = bits.Add64(x45, x59, uint64(0x0))
+	var x63 uint64
+	var x64 uint64
+	x63, x64 = bits.Add64(x47, x60, uint64(p521Uint1(x62)))
+	var x65 uint64
+	var x66 uint64
+	x65, x66 = bits.Add64(x49, uint64(0x0), uint64(p521Uint1(x64)))
+	var x67 uint64
+	var x68 uint64
+	x67, x68 = bits.Add64(x51, uint64(0x0), uint64(p521Uint1(x66)))
+	var x69 uint64
+	var x70 uint64
+	x69, x70 = bits.Add64(x53, uint64(0x0), uint64(p521Uint1(x68)))
+	var x71 uint64
+	var x72 uint64
+	x71, x72 = bits.Add64(x55, uint64(0x0), uint64(p521Uint1(x70)))
+	var x73 uint64
+	var x74 uint64
+	x73, x74 = bits.Add64(x57, uint64(0x0), uint64(p521Uint1(x72)))
+	var x75 uint64
+	var x76 uint64
+	x76, x75 = bits.Mul64(x43, 0x1ff)
+	var x77 uint64
+	var x78 uint64
+	x78, x77 = bits.Mul64(x43, 0xffffffffffffffff)
+	var x79 uint64
+	var x80 uint64
+	x80, x79 = bits.Mul64(x43, 0xffffffffffffffff)
+	var x81 uint64
+	var x82 uint64
+	x82, x81 = bits.Mul64(x43, 0xffffffffffffffff)
+	var x83 uint64
+	var x84 uint64
+	x84, x83 = bits.Mul64(x43, 0xffffffffffffffff)
+	var x85 uint64
+	var x86 uint64
+	x86, x85 = bits.Mul64(x43, 0xffffffffffffffff)
+	var x87 uint64
+	var x88 uint64
+	x88, x87 = bits.Mul64(x43, 0xffffffffffffffff)
+	var x89 uint64
+	var x90 uint64
+	x90, x89 = bits.Mul64(x43, 0xffffffffffffffff)
+	var x91 uint64
+	var x92 uint64
+	x92, x91 = bits.Mul64(x43, 0xffffffffffffffff)
+	var x93 uint64
+	var x94 uint64
+	x93, x94 = bits.Add64(x92, x89, uint64(0x0))
+	var x95 uint64
+	var x96 uint64
+	x95, x96 = bits.Add64(x90, x87, uint64(p521Uint1(x94)))
+	var x97 uint64
+	var x98 uint64
+	x97, x98 = bits.Add64(x88, x85, uint64(p521Uint1(x96)))
+	var x99 uint64
+	var x100 uint64
+	x99, x100 = bits.Add64(x86, x83, uint64(p521Uint1(x98)))
+	var x101 uint64
+	var x102 uint64
+	x101, x102 = bits.Add64(x84, x81, uint64(p521Uint1(x100)))
+	var x103 uint64
+	var x104 uint64
+	x103, x104 = bits.Add64(x82, x79, uint64(p521Uint1(x102)))
+	var x105 uint64
+	var x106 uint64
+	x105, x106 = bits.Add64(x80, x77, uint64(p521Uint1(x104)))
+	var x107 uint64
+	var x108 uint64
+	x107, x108 = bits.Add64(x78, x75, uint64(p521Uint1(x106)))
+	var x110 uint64
+	_, x110 = bits.Add64(x43, x91, uint64(0x0))
+	var x111 uint64
+	var x112 uint64
+	x111, x112 = bits.Add64(x61, x93, uint64(p521Uint1(x110)))
+	var x113 uint64
+	var x114 uint64
+	x113, x114 = bits.Add64(x63, x95, uint64(p521Uint1(x112)))
+	var x115 uint64
+	var x116 uint64
+	x115, x116 = bits.Add64(x65, x97, uint64(p521Uint1(x114)))
+	var x117 uint64
+	var x118 uint64
+	x117, x118 = bits.Add64(x67, x99, uint64(p521Uint1(x116)))
+	var x119 uint64
+	var x120 uint64
+	x119, x120 = bits.Add64(x69, x101, uint64(p521Uint1(x118)))
+	var x121 uint64
+	var x122 uint64
+	x121, x122 = bits.Add64(x71, x103, uint64(p521Uint1(x120)))
+	var x123 uint64
+	var x124 uint64
+	x123, x124 = bits.Add64(x73, x105, uint64(p521Uint1(x122)))
+	var x125 uint64
+	var x126 uint64
+	x125, x126 = bits.Add64((uint64(p521Uint1(x74)) + (uint64(p521Uint1(x58)) + (uint64(p521Uint1(x40)) + x8))), x107, uint64(p521Uint1(x124)))
+	var x127 uint64
+	var x128 uint64
+	x128, x127 = bits.Mul64(arg1[3], 0x400000000000)
+	var x129 uint64
+	var x130 uint64
+	x129, x130 = bits.Add64(x113, x127, uint64(0x0))
+	var x131 uint64
+	var x132 uint64
+	x131, x132 = bits.Add64(x115, x128, uint64(p521Uint1(x130)))
+	var x133 uint64
+	var x134 uint64
+	x133, x134 = bits.Add64(x117, uint64(0x0), uint64(p521Uint1(x132)))
+	var x135 uint64
+	var x136 uint64
+	x135, x136 = bits.Add64(x119, uint64(0x0), uint64(p521Uint1(x134)))
+	var x137 uint64
+	var x138 uint64
+	x137, x138 = bits.Add64(x121, uint64(0x0), uint64(p521Uint1(x136)))
+	var x139 uint64
+	var x140 uint64
+	x139, x140 = bits.Add64(x123, uint64(0x0), uint64(p521Uint1(x138)))
+	var x141 uint64
+	var x142 uint64
+	x141, x142 = bits.Add64(x125, uint64(0x0), uint64(p521Uint1(x140)))
+	var x143 uint64
+	var x144 uint64
+	x144, x143 = bits.Mul64(x111, 0x1ff)
+	var x145 uint64
+	var x146 uint64
+	x146, x145 = bits.Mul64(x111, 0xffffffffffffffff)
+	var x147 uint64
+	var x148 uint64
+	x148, x147 = bits.Mul64(x111, 0xffffffffffffffff)
+	var x149 uint64
+	var x150 uint64
+	x150, x149 = bits.Mul64(x111, 0xffffffffffffffff)
+	var x151 uint64
+	var x152 uint64
+	x152, x151 = bits.Mul64(x111, 0xffffffffffffffff)
+	var x153 uint64
+	var x154 uint64
+	x154, x153 = bits.Mul64(x111, 0xffffffffffffffff)
+	var x155 uint64
+	var x156 uint64
+	x156, x155 = bits.Mul64(x111, 0xffffffffffffffff)
+	var x157 uint64
+	var x158 uint64
+	x158, x157 = bits.Mul64(x111, 0xffffffffffffffff)
+	var x159 uint64
+	var x160 uint64
+	x160, x159 = bits.Mul64(x111, 0xffffffffffffffff)
+	var x161 uint64
+	var x162 uint64
+	x161, x162 = bits.Add64(x160, x157, uint64(0x0))
+	var x163 uint64
+	var x164 uint64
+	x163, x164 = bits.Add64(x158, x155, uint64(p521Uint1(x162)))
+	var x165 uint64
+	var x166 uint64
+	x165, x166 = bits.Add64(x156, x153, uint64(p521Uint1(x164)))
+	var x167 uint64
+	var x168 uint64
+	x167, x168 = bits.Add64(x154, x151, uint64(p521Uint1(x166)))
+	var x169 uint64
+	var x170 uint64
+	x169, x170 = bits.Add64(x152, x149, uint64(p521Uint1(x168)))
+	var x171 uint64
+	var x172 uint64
+	x171, x172 = bits.Add64(x150, x147, uint64(p521Uint1(x170)))
+	var x173 uint64
+	var x174 uint64
+	x173, x174 = bits.Add64(x148, x145, uint64(p521Uint1(x172)))
+	var x175 uint64
+	var x176 uint64
+	x175, x176 = bits.Add64(x146, x143, uint64(p521Uint1(x174)))
+	var x178 uint64
+	_, x178 = bits.Add64(x111, x159, uint64(0x0))
+	var x179 uint64
+	var x180 uint64
+	x179, x180 = bits.Add64(x129, x161, uint64(p521Uint1(x178)))
+	var x181 uint64
+	var x182 uint64
+	x181, x182 = bits.Add64(x131, x163, uint64(p521Uint1(x180)))
+	var x183 uint64
+	var x184 uint64
+	x183, x184 = bits.Add64(x133, x165, uint64(p521Uint1(x182)))
+	var x185 uint64
+	var x186 uint64
+	x185, x186 = bits.Add64(x135, x167, uint64(p521Uint1(x184)))
+	var x187 uint64
+	var x188 uint64
+	x187, x188 = bits.Add64(x137, x169, uint64(p521Uint1(x186)))
+	var x189 uint64
+	var x190 uint64
+	x189, x190 = bits.Add64(x139, x171, uint64(p521Uint1(x188)))
+	var x191 uint64
+	var x192 uint64
+	x191, x192 = bits.Add64(x141, x173, uint64(p521Uint1(x190)))
+	var x193 uint64
+	var x194 uint64
+	x193, x194 = bits.Add64((uint64(p521Uint1(x142)) + (uint64(p521Uint1(x126)) + (uint64(p521Uint1(x108)) + x76))), x175, uint64(p521Uint1(x192)))
+	var x195 uint64
+	var x196 uint64
+	x196, x195 = bits.Mul64(arg1[4], 0x400000000000)
+	var x197 uint64
+	var x198 uint64
+	x197, x198 = bits.Add64(x181, x195, uint64(0x0))
+	var x199 uint64
+	var x200 uint64
+	x199, x200 = bits.Add64(x183, x196, uint64(p521Uint1(x198)))
+	var x201 uint64
+	var x202 uint64
+	x201, x202 = bits.Add64(x185, uint64(0x0), uint64(p521Uint1(x200)))
+	var x203 uint64
+	var x204 uint64
+	x203, x204 = bits.Add64(x187, uint64(0x0), uint64(p521Uint1(x202)))
+	var x205 uint64
+	var x206 uint64
+	x205, x206 = bits.Add64(x189, uint64(0x0), uint64(p521Uint1(x204)))
+	var x207 uint64
+	var x208 uint64
+	x207, x208 = bits.Add64(x191, uint64(0x0), uint64(p521Uint1(x206)))
+	var x209 uint64
+	var x210 uint64
+	x209, x210 = bits.Add64(x193, uint64(0x0), uint64(p521Uint1(x208)))
+	var x211 uint64
+	var x212 uint64
+	x212, x211 = bits.Mul64(x179, 0x1ff)
+	var x213 uint64
+	var x214 uint64
+	x214, x213 = bits.Mul64(x179, 0xffffffffffffffff)
+	var x215 uint64
+	var x216 uint64
+	x216, x215 = bits.Mul64(x179, 0xffffffffffffffff)
+	var x217 uint64
+	var x218 uint64
+	x218, x217 = bits.Mul64(x179, 0xffffffffffffffff)
+	var x219 uint64
+	var x220 uint64
+	x220, x219 = bits.Mul64(x179, 0xffffffffffffffff)
+	var x221 uint64
+	var x222 uint64
+	x222, x221 = bits.Mul64(x179, 0xffffffffffffffff)
+	var x223 uint64
+	var x224 uint64
+	x224, x223 = bits.Mul64(x179, 0xffffffffffffffff)
+	var x225 uint64
+	var x226 uint64
+	x226, x225 = bits.Mul64(x179, 0xffffffffffffffff)
+	var x227 uint64
+	var x228 uint64
+	x228, x227 = bits.Mul64(x179, 0xffffffffffffffff)
+	var x229 uint64
+	var x230 uint64
+	x229, x230 = bits.Add64(x228, x225, uint64(0x0))
+	var x231 uint64
+	var x232 uint64
+	x231, x232 = bits.Add64(x226, x223, uint64(p521Uint1(x230)))
+	var x233 uint64
+	var x234 uint64
+	x233, x234 = bits.Add64(x224, x221, uint64(p521Uint1(x232)))
+	var x235 uint64
+	var x236 uint64
+	x235, x236 = bits.Add64(x222, x219, uint64(p521Uint1(x234)))
+	var x237 uint64
+	var x238 uint64
+	x237, x238 = bits.Add64(x220, x217, uint64(p521Uint1(x236)))
+	var x239 uint64
+	var x240 uint64
+	x239, x240 = bits.Add64(x218, x215, uint64(p521Uint1(x238)))
+	var x241 uint64
+	var x242 uint64
+	x241, x242 = bits.Add64(x216, x213, uint64(p521Uint1(x240)))
+	var x243 uint64
+	var x244 uint64
+	x243, x244 = bits.Add64(x214, x211, uint64(p521Uint1(x242)))
+	var x246 uint64
+	_, x246 = bits.Add64(x179, x227, uint64(0x0))
+	var x247 uint64
+	var x248 uint64
+	x247, x248 = bits.Add64(x197, x229, uint64(p521Uint1(x246)))
+	var x249 uint64
+	var x250 uint64
+	x249, x250 = bits.Add64(x199, x231, uint64(p521Uint1(x248)))
+	var x251 uint64
+	var x252 uint64
+	x251, x252 = bits.Add64(x201, x233, uint64(p521Uint1(x250)))
+	var x253 uint64
+	var x254 uint64
+	x253, x254 = bits.Add64(x203, x235, uint64(p521Uint1(x252)))
+	var x255 uint64
+	var x256 uint64
+	x255, x256 = bits.Add64(x205, x237, uint64(p521Uint1(x254)))
+	var x257 uint64
+	var x258 uint64
+	x257, x258 = bits.Add64(x207, x239, uint64(p521Uint1(x256)))
+	var x259 uint64
+	var x260 uint64
+	x259, x260 = bits.Add64(x209, x241, uint64(p521Uint1(x258)))
+	var x261 uint64
+	var x262 uint64
+	x261, x262 = bits.Add64((uint64(p521Uint1(x210)) + (uint64(p521Uint1(x194)) + (uint64(p521Uint1(x176)) + x144))), x243, uint64(p521Uint1(x260)))
+	var x263 uint64
+	var x264 uint64
+	x264, x263 = bits.Mul64(arg1[5], 0x400000000000)
+	var x265 uint64
+	var x266 uint64
+	x265, x266 = bits.Add64(x249, x263, uint64(0x0))
+	var x267 uint64
+	var x268 uint64
+	x267, x268 = bits.Add64(x251, x264, uint64(p521Uint1(x266)))
+	var x269 uint64
+	var x270 uint64
+	x269, x270 = bits.Add64(x253, uint64(0x0), uint64(p521Uint1(x268)))
+	var x271 uint64
+	var x272 uint64
+	x271, x272 = bits.Add64(x255, uint64(0x0), uint64(p521Uint1(x270)))
+	var x273 uint64
+	var x274 uint64
+	x273, x274 = bits.Add64(x257, uint64(0x0), uint64(p521Uint1(x272)))
+	var x275 uint64
+	var x276 uint64
+	x275, x276 = bits.Add64(x259, uint64(0x0), uint64(p521Uint1(x274)))
+	var x277 uint64
+	var x278 uint64
+	x277, x278 = bits.Add64(x261, uint64(0x0), uint64(p521Uint1(x276)))
+	var x279 uint64
+	var x280 uint64
+	x280, x279 = bits.Mul64(x247, 0x1ff)
+	var x281 uint64
+	var x282 uint64
+	x282, x281 = bits.Mul64(x247, 0xffffffffffffffff)
+	var x283 uint64
+	var x284 uint64
+	x284, x283 = bits.Mul64(x247, 0xffffffffffffffff)
+	var x285 uint64
+	var x286 uint64
+	x286, x285 = bits.Mul64(x247, 0xffffffffffffffff)
+	var x287 uint64
+	var x288 uint64
+	x288, x287 = bits.Mul64(x247, 0xffffffffffffffff)
+	var x289 uint64
+	var x290 uint64
+	x290, x289 = bits.Mul64(x247, 0xffffffffffffffff)
+	var x291 uint64
+	var x292 uint64
+	x292, x291 = bits.Mul64(x247, 0xffffffffffffffff)
+	var x293 uint64
+	var x294 uint64
+	x294, x293 = bits.Mul64(x247, 0xffffffffffffffff)
+	var x295 uint64
+	var x296 uint64
+	x296, x295 = bits.Mul64(x247, 0xffffffffffffffff)
+	var x297 uint64
+	var x298 uint64
+	x297, x298 = bits.Add64(x296, x293, uint64(0x0))
+	var x299 uint64
+	var x300 uint64
+	x299, x300 = bits.Add64(x294, x291, uint64(p521Uint1(x298)))
+	var x301 uint64
+	var x302 uint64
+	x301, x302 = bits.Add64(x292, x289, uint64(p521Uint1(x300)))
+	var x303 uint64
+	var x304 uint64
+	x303, x304 = bits.Add64(x290, x287, uint64(p521Uint1(x302)))
+	var x305 uint64
+	var x306 uint64
+	x305, x306 = bits.Add64(x288, x285, uint64(p521Uint1(x304)))
+	var x307 uint64
+	var x308 uint64
+	x307, x308 = bits.Add64(x286, x283, uint64(p521Uint1(x306)))
+	var x309 uint64
+	var x310 uint64
+	x309, x310 = bits.Add64(x284, x281, uint64(p521Uint1(x308)))
+	var x311 uint64
+	var x312 uint64
+	x311, x312 = bits.Add64(x282, x279, uint64(p521Uint1(x310)))
+	var x314 uint64
+	_, x314 = bits.Add64(x247, x295, uint64(0x0))
+	var x315 uint64
+	var x316 uint64
+	x315, x316 = bits.Add64(x265, x297, uint64(p521Uint1(x314)))
+	var x317 uint64
+	var x318 uint64
+	x317, x318 = bits.Add64(x267, x299, uint64(p521Uint1(x316)))
+	var x319 uint64
+	var x320 uint64
+	x319, x320 = bits.Add64(x269, x301, uint64(p521Uint1(x318)))
+	var x321 uint64
+	var x322 uint64
+	x321, x322 = bits.Add64(x271, x303, uint64(p521Uint1(x320)))
+	var x323 uint64
+	var x324 uint64
+	x323, x324 = bits.Add64(x273, x305, uint64(p521Uint1(x322)))
+	var x325 uint64
+	var x326 uint64
+	x325, x326 = bits.Add64(x275, x307, uint64(p521Uint1(x324)))
+	var x327 uint64
+	var x328 uint64
+	x327, x328 = bits.Add64(x277, x309, uint64(p521Uint1(x326)))
+	var x329 uint64
+	var x330 uint64
+	x329, x330 = bits.Add64((uint64(p521Uint1(x278)) + (uint64(p521Uint1(x262)) + (uint64(p521Uint1(x244)) + x212))), x311, uint64(p521Uint1(x328)))
+	var x331 uint64
+	var x332 uint64
+	x332, x331 = bits.Mul64(arg1[6], 0x400000000000)
+	var x333 uint64
+	var x334 uint64
+	x333, x334 = bits.Add64(x317, x331, uint64(0x0))
+	var x335 uint64
+	var x336 uint64
+	x335, x336 = bits.Add64(x319, x332, uint64(p521Uint1(x334)))
+	var x337 uint64
+	var x338 uint64
+	x337, x338 = bits.Add64(x321, uint64(0x0), uint64(p521Uint1(x336)))
+	var x339 uint64
+	var x340 uint64
+	x339, x340 = bits.Add64(x323, uint64(0x0), uint64(p521Uint1(x338)))
+	var x341 uint64
+	var x342 uint64
+	x341, x342 = bits.Add64(x325, uint64(0x0), uint64(p521Uint1(x340)))
+	var x343 uint64
+	var x344 uint64
+	x343, x344 = bits.Add64(x327, uint64(0x0), uint64(p521Uint1(x342)))
+	var x345 uint64
+	var x346 uint64
+	x345, x346 = bits.Add64(x329, uint64(0x0), uint64(p521Uint1(x344)))
+	var x347 uint64
+	var x348 uint64
+	x348, x347 = bits.Mul64(x315, 0x1ff)
+	var x349 uint64
+	var x350 uint64
+	x350, x349 = bits.Mul64(x315, 0xffffffffffffffff)
+	var x351 uint64
+	var x352 uint64
+	x352, x351 = bits.Mul64(x315, 0xffffffffffffffff)
+	var x353 uint64
+	var x354 uint64
+	x354, x353 = bits.Mul64(x315, 0xffffffffffffffff)
+	var x355 uint64
+	var x356 uint64
+	x356, x355 = bits.Mul64(x315, 0xffffffffffffffff)
+	var x357 uint64
+	var x358 uint64
+	x358, x357 = bits.Mul64(x315, 0xffffffffffffffff)
+	var x359 uint64
+	var x360 uint64
+	x360, x359 = bits.Mul64(x315, 0xffffffffffffffff)
+	var x361 uint64
+	var x362 uint64
+	x362, x361 = bits.Mul64(x315, 0xffffffffffffffff)
+	var x363 uint64
+	var x364 uint64
+	x364, x363 = bits.Mul64(x315, 0xffffffffffffffff)
+	var x365 uint64
+	var x366 uint64
+	x365, x366 = bits.Add64(x364, x361, uint64(0x0))
+	var x367 uint64
+	var x368 uint64
+	x367, x368 = bits.Add64(x362, x359, uint64(p521Uint1(x366)))
+	var x369 uint64
+	var x370 uint64
+	x369, x370 = bits.Add64(x360, x357, uint64(p521Uint1(x368)))
+	var x371 uint64
+	var x372 uint64
+	x371, x372 = bits.Add64(x358, x355, uint64(p521Uint1(x370)))
+	var x373 uint64
+	var x374 uint64
+	x373, x374 = bits.Add64(x356, x353, uint64(p521Uint1(x372)))
+	var x375 uint64
+	var x376 uint64
+	x375, x376 = bits.Add64(x354, x351, uint64(p521Uint1(x374)))
+	var x377 uint64
+	var x378 uint64
+	x377, x378 = bits.Add64(x352, x349, uint64(p521Uint1(x376)))
+	var x379 uint64
+	var x380 uint64
+	x379, x380 = bits.Add64(x350, x347, uint64(p521Uint1(x378)))
+	var x382 uint64
+	_, x382 = bits.Add64(x315, x363, uint64(0x0))
+	var x383 uint64
+	var x384 uint64
+	x383, x384 = bits.Add64(x333, x365, uint64(p521Uint1(x382)))
+	var x385 uint64
+	var x386 uint64
+	x385, x386 = bits.Add64(x335, x367, uint64(p521Uint1(x384)))
+	var x387 uint64
+	var x388 uint64
+	x387, x388 = bits.Add64(x337, x369, uint64(p521Uint1(x386)))
+	var x389 uint64
+	var x390 uint64
+	x389, x390 = bits.Add64(x339, x371, uint64(p521Uint1(x388)))
+	var x391 uint64
+	var x392 uint64
+	x391, x392 = bits.Add64(x341, x373, uint64(p521Uint1(x390)))
+	var x393 uint64
+	var x394 uint64
+	x393, x394 = bits.Add64(x343, x375, uint64(p521Uint1(x392)))
+	var x395 uint64
+	var x396 uint64
+	x395, x396 = bits.Add64(x345, x377, uint64(p521Uint1(x394)))
+	var x397 uint64
+	var x398 uint64
+	x397, x398 = bits.Add64((uint64(p521Uint1(x346)) + (uint64(p521Uint1(x330)) + (uint64(p521Uint1(x312)) + x280))), x379, uint64(p521Uint1(x396)))
+	var x399 uint64
+	var x400 uint64
+	x400, x399 = bits.Mul64(arg1[7], 0x400000000000)
+	var x401 uint64
+	var x402 uint64
+	x401, x402 = bits.Add64(x385, x399, uint64(0x0))
+	var x403 uint64
+	var x404 uint64
+	x403, x404 = bits.Add64(x387, x400, uint64(p521Uint1(x402)))
+	var x405 uint64
+	var x406 uint64
+	x405, x406 = bits.Add64(x389, uint64(0x0), uint64(p521Uint1(x404)))
+	var x407 uint64
+	var x408 uint64
+	x407, x408 = bits.Add64(x391, uint64(0x0), uint64(p521Uint1(x406)))
+	var x409 uint64
+	var x410 uint64
+	x409, x410 = bits.Add64(x393, uint64(0x0), uint64(p521Uint1(x408)))
+	var x411 uint64
+	var x412 uint64
+	x411, x412 = bits.Add64(x395, uint64(0x0), uint64(p521Uint1(x410)))
+	var x413 uint64
+	var x414 uint64
+	x413, x414 = bits.Add64(x397, uint64(0x0), uint64(p521Uint1(x412)))
+	var x415 uint64
+	var x416 uint64
+	x416, x415 = bits.Mul64(x383, 0x1ff)
+	var x417 uint64
+	var x418 uint64
+	x418, x417 = bits.Mul64(x383, 0xffffffffffffffff)
+	var x419 uint64
+	var x420 uint64
+	x420, x419 = bits.Mul64(x383, 0xffffffffffffffff)
+	var x421 uint64
+	var x422 uint64
+	x422, x421 = bits.Mul64(x383, 0xffffffffffffffff)
+	var x423 uint64
+	var x424 uint64
+	x424, x423 = bits.Mul64(x383, 0xffffffffffffffff)
+	var x425 uint64
+	var x426 uint64
+	x426, x425 = bits.Mul64(x383, 0xffffffffffffffff)
+	var x427 uint64
+	var x428 uint64
+	x428, x427 = bits.Mul64(x383, 0xffffffffffffffff)
+	var x429 uint64
+	var x430 uint64
+	x430, x429 = bits.Mul64(x383, 0xffffffffffffffff)
+	var x431 uint64
+	var x432 uint64
+	x432, x431 = bits.Mul64(x383, 0xffffffffffffffff)
+	var x433 uint64
+	var x434 uint64
+	x433, x434 = bits.Add64(x432, x429, uint64(0x0))
+	var x435 uint64
+	var x436 uint64
+	x435, x436 = bits.Add64(x430, x427, uint64(p521Uint1(x434)))
+	var x437 uint64
+	var x438 uint64
+	x437, x438 = bits.Add64(x428, x425, uint64(p521Uint1(x436)))
+	var x439 uint64
+	var x440 uint64
+	x439, x440 = bits.Add64(x426, x423, uint64(p521Uint1(x438)))
+	var x441 uint64
+	var x442 uint64
+	x441, x442 = bits.Add64(x424, x421, uint64(p521Uint1(x440)))
+	var x443 uint64
+	var x444 uint64
+	x443, x444 = bits.Add64(x422, x419, uint64(p521Uint1(x442)))
+	var x445 uint64
+	var x446 uint64
+	x445, x446 = bits.Add64(x420, x417, uint64(p521Uint1(x444)))
+	var x447 uint64
+	var x448 uint64
+	x447, x448 = bits.Add64(x418, x415, uint64(p521Uint1(x446)))
+	var x450 uint64
+	_, x450 = bits.Add64(x383, x431, uint64(0x0))
+	var x451 uint64
+	var x452 uint64
+	x451, x452 = bits.Add64(x401, x433, uint64(p521Uint1(x450)))
+	var x453 uint64
+	var x454 uint64
+	x453, x454 = bits.Add64(x403, x435, uint64(p521Uint1(x452)))
+	var x455 uint64
+	var x456 uint64
+	x455, x456 = bits.Add64(x405, x437, uint64(p521Uint1(x454)))
+	var x457 uint64
+	var x458 uint64
+	x457, x458 = bits.Add64(x407, x439, uint64(p521Uint1(x456)))
+	var x459 uint64
+	var x460 uint64
+	x459, x460 = bits.Add64(x409, x441, uint64(p521Uint1(x458)))
+	var x461 uint64
+	var x462 uint64
+	x461, x462 = bits.Add64(x411, x443, uint64(p521Uint1(x460)))
+	var x463 uint64
+	var x464 uint64
+	x463, x464 = bits.Add64(x413, x445, uint64(p521Uint1(x462)))
+	var x465 uint64
+	var x466 uint64
+	x465, x466 = bits.Add64((uint64(p521Uint1(x414)) + (uint64(p521Uint1(x398)) + (uint64(p521Uint1(x380)) + x348))), x447, uint64(p521Uint1(x464)))
+	var x467 uint64
+	var x468 uint64
+	x468, x467 = bits.Mul64(arg1[8], 0x400000000000)
+	var x469 uint64
+	var x470 uint64
+	x469, x470 = bits.Add64(x453, x467, uint64(0x0))
+	var x471 uint64
+	var x472 uint64
+	x471, x472 = bits.Add64(x455, x468, uint64(p521Uint1(x470)))
+	var x473 uint64
+	var x474 uint64
+	x473, x474 = bits.Add64(x457, uint64(0x0), uint64(p521Uint1(x472)))
+	var x475 uint64
+	var x476 uint64
+	x475, x476 = bits.Add64(x459, uint64(0x0), uint64(p521Uint1(x474)))
+	var x477 uint64
+	var x478 uint64
+	x477, x478 = bits.Add64(x461, uint64(0x0), uint64(p521Uint1(x476)))
+	var x479 uint64
+	var x480 uint64
+	x479, x480 = bits.Add64(x463, uint64(0x0), uint64(p521Uint1(x478)))
+	var x481 uint64
+	var x482 uint64
+	x481, x482 = bits.Add64(x465, uint64(0x0), uint64(p521Uint1(x480)))
+	var x483 uint64
+	var x484 uint64
+	x484, x483 = bits.Mul64(x451, 0x1ff)
+	var x485 uint64
+	var x486 uint64
+	x486, x485 = bits.Mul64(x451, 0xffffffffffffffff)
+	var x487 uint64
+	var x488 uint64
+	x488, x487 = bits.Mul64(x451, 0xffffffffffffffff)
+	var x489 uint64
+	var x490 uint64
+	x490, x489 = bits.Mul64(x451, 0xffffffffffffffff)
+	var x491 uint64
+	var x492 uint64
+	x492, x491 = bits.Mul64(x451, 0xffffffffffffffff)
+	var x493 uint64
+	var x494 uint64
+	x494, x493 = bits.Mul64(x451, 0xffffffffffffffff)
+	var x495 uint64
+	var x496 uint64
+	x496, x495 = bits.Mul64(x451, 0xffffffffffffffff)
+	var x497 uint64
+	var x498 uint64
+	x498, x497 = bits.Mul64(x451, 0xffffffffffffffff)
+	var x499 uint64
+	var x500 uint64
+	x500, x499 = bits.Mul64(x451, 0xffffffffffffffff)
+	var x501 uint64
+	var x502 uint64
+	x501, x502 = bits.Add64(x500, x497, uint64(0x0))
+	var x503 uint64
+	var x504 uint64
+	x503, x504 = bits.Add64(x498, x495, uint64(p521Uint1(x502)))
+	var x505 uint64
+	var x506 uint64
+	x505, x506 = bits.Add64(x496, x493, uint64(p521Uint1(x504)))
+	var x507 uint64
+	var x508 uint64
+	x507, x508 = bits.Add64(x494, x491, uint64(p521Uint1(x506)))
+	var x509 uint64
+	var x510 uint64
+	x509, x510 = bits.Add64(x492, x489, uint64(p521Uint1(x508)))
+	var x511 uint64
+	var x512 uint64
+	x511, x512 = bits.Add64(x490, x487, uint64(p521Uint1(x510)))
+	var x513 uint64
+	var x514 uint64
+	x513, x514 = bits.Add64(x488, x485, uint64(p521Uint1(x512)))
+	var x515 uint64
+	var x516 uint64
+	x515, x516 = bits.Add64(x486, x483, uint64(p521Uint1(x514)))
+	var x518 uint64
+	_, x518 = bits.Add64(x451, x499, uint64(0x0))
+	var x519 uint64
+	var x520 uint64
+	x519, x520 = bits.Add64(x469, x501, uint64(p521Uint1(x518)))
+	var x521 uint64
+	var x522 uint64
+	x521, x522 = bits.Add64(x471, x503, uint64(p521Uint1(x520)))
+	var x523 uint64
+	var x524 uint64
+	x523, x524 = bits.Add64(x473, x505, uint64(p521Uint1(x522)))
+	var x525 uint64
+	var x526 uint64
+	x525, x526 = bits.Add64(x475, x507, uint64(p521Uint1(x524)))
+	var x527 uint64
+	var x528 uint64
+	x527, x528 = bits.Add64(x477, x509, uint64(p521Uint1(x526)))
+	var x529 uint64
+	var x530 uint64
+	x529, x530 = bits.Add64(x479, x511, uint64(p521Uint1(x528)))
+	var x531 uint64
+	var x532 uint64
+	x531, x532 = bits.Add64(x481, x513, uint64(p521Uint1(x530)))
+	var x533 uint64
+	var x534 uint64
+	x533, x534 = bits.Add64((uint64(p521Uint1(x482)) + (uint64(p521Uint1(x466)) + (uint64(p521Uint1(x448)) + x416))), x515, uint64(p521Uint1(x532)))
+	x535 := (uint64(p521Uint1(x534)) + (uint64(p521Uint1(x516)) + x484))
+	var x536 uint64
+	var x537 uint64
+	x536, x537 = bits.Sub64(x519, 0xffffffffffffffff, uint64(0x0))
+	var x538 uint64
+	var x539 uint64
+	x538, x539 = bits.Sub64(x521, 0xffffffffffffffff, uint64(p521Uint1(x537)))
+	var x540 uint64
+	var x541 uint64
+	x540, x541 = bits.Sub64(x523, 0xffffffffffffffff, uint64(p521Uint1(x539)))
+	var x542 uint64
+	var x543 uint64
+	x542, x543 = bits.Sub64(x525, 0xffffffffffffffff, uint64(p521Uint1(x541)))
+	var x544 uint64
+	var x545 uint64
+	x544, x545 = bits.Sub64(x527, 0xffffffffffffffff, uint64(p521Uint1(x543)))
+	var x546 uint64
+	var x547 uint64
+	x546, x547 = bits.Sub64(x529, 0xffffffffffffffff, uint64(p521Uint1(x545)))
+	var x548 uint64
+	var x549 uint64
+	x548, x549 = bits.Sub64(x531, 0xffffffffffffffff, uint64(p521Uint1(x547)))
+	var x550 uint64
+	var x551 uint64
+	x550, x551 = bits.Sub64(x533, 0xffffffffffffffff, uint64(p521Uint1(x549)))
+	var x552 uint64
+	var x553 uint64
+	x552, x553 = bits.Sub64(x535, 0x1ff, uint64(p521Uint1(x551)))
+	var x555 uint64
+	_, x555 = bits.Sub64(uint64(0x0), uint64(0x0), uint64(p521Uint1(x553)))
+	var x556 uint64
+	p521CmovznzU64(&x556, p521Uint1(x555), x536, x519)
+	var x557 uint64
+	p521CmovznzU64(&x557, p521Uint1(x555), x538, x521)
+	var x558 uint64
+	p521CmovznzU64(&x558, p521Uint1(x555), x540, x523)
+	var x559 uint64
+	p521CmovznzU64(&x559, p521Uint1(x555), x542, x525)
+	var x560 uint64
+	p521CmovznzU64(&x560, p521Uint1(x555), x544, x527)
+	var x561 uint64
+	p521CmovznzU64(&x561, p521Uint1(x555), x546, x529)
+	var x562 uint64
+	p521CmovznzU64(&x562, p521Uint1(x555), x548, x531)
+	var x563 uint64
+	p521CmovznzU64(&x563, p521Uint1(x555), x550, x533)
+	var x564 uint64
+	p521CmovznzU64(&x564, p521Uint1(x555), x552, x535)
+	out1[0] = x556
+	out1[1] = x557
+	out1[2] = x558
+	out1[3] = x559
+	out1[4] = x560
+	out1[5] = x561
+	out1[6] = x562
+	out1[7] = x563
+	out1[8] = x564
+}
+
+// p521Selectznz is a multi-limb conditional select.
+//
+// Postconditions:
+//
+//	eval out1 = (if arg1 = 0 then eval arg2 else eval arg3)
+//
+// Input Bounds:
+//
+//	arg1: [0x0 ~> 0x1]
+//	arg2: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
+//	arg3: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
+//
+// Output Bounds:
+//
+//	out1: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff]]
+func p521Selectznz(out1 *[9]uint64, arg1 p521Uint1, arg2 *[9]uint64, arg3 *[9]uint64) {
+	var x1 uint64
+	p521CmovznzU64(&x1, arg1, arg2[0], arg3[0])
+	var x2 uint64
+	p521CmovznzU64(&x2, arg1, arg2[1], arg3[1])
+	var x3 uint64
+	p521CmovznzU64(&x3, arg1, arg2[2], arg3[2])
+	var x4 uint64
+	p521CmovznzU64(&x4, arg1, arg2[3], arg3[3])
+	var x5 uint64
+	p521CmovznzU64(&x5, arg1, arg2[4], arg3[4])
+	var x6 uint64
+	p521CmovznzU64(&x6, arg1, arg2[5], arg3[5])
+	var x7 uint64
+	p521CmovznzU64(&x7, arg1, arg2[6], arg3[6])
+	var x8 uint64
+	p521CmovznzU64(&x8, arg1, arg2[7], arg3[7])
+	var x9 uint64
+	p521CmovznzU64(&x9, arg1, arg2[8], arg3[8])
+	out1[0] = x1
+	out1[1] = x2
+	out1[2] = x3
+	out1[3] = x4
+	out1[4] = x5
+	out1[5] = x6
+	out1[6] = x7
+	out1[7] = x8
+	out1[8] = x9
+}
+
+// p521ToBytes serializes a field element NOT in the Montgomery domain to bytes in little-endian order.
+//
+// Preconditions:
+//
+//	0 ≤ eval arg1 < m
+//
+// Postconditions:
+//
+//	out1 = map (λ x, ⌊((eval arg1 mod m) mod 2^(8 * (x + 1))) / 2^(8 * x)⌋) [0..65]
+//
+// Input Bounds:
+//
+//	arg1: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0x1ff]]
+//
+// Output Bounds:
+//
+//	out1: [[0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0x1]]
+func p521ToBytes(out1 *[66]uint8, arg1 *[9]uint64) {
+	x1 := arg1[8]
+	x2 := arg1[7]
+	x3 := arg1[6]
+	x4 := arg1[5]
+	x5 := arg1[4]
+	x6 := arg1[3]
+	x7 := arg1[2]
+	x8 := arg1[1]
+	x9 := arg1[0]
+	x10 := (uint8(x9) & 0xff)
+	x11 := (x9 >> 8)
+	x12 := (uint8(x11) & 0xff)
+	x13 := (x11 >> 8)
+	x14 := (uint8(x13) & 0xff)
+	x15 := (x13 >> 8)
+	x16 := (uint8(x15) & 0xff)
+	x17 := (x15 >> 8)
+	x18 := (uint8(x17) & 0xff)
+	x19 := (x17 >> 8)
+	x20 := (uint8(x19) & 0xff)
+	x21 := (x19 >> 8)
+	x22 := (uint8(x21) & 0xff)
+	x23 := uint8((x21 >> 8))
+	x24 := (uint8(x8) & 0xff)
+	x25 := (x8 >> 8)
+	x26 := (uint8(x25) & 0xff)
+	x27 := (x25 >> 8)
+	x28 := (uint8(x27) & 0xff)
+	x29 := (x27 >> 8)
+	x30 := (uint8(x29) & 0xff)
+	x31 := (x29 >> 8)
+	x32 := (uint8(x31) & 0xff)
+	x33 := (x31 >> 8)
+	x34 := (uint8(x33) & 0xff)
+	x35 := (x33 >> 8)
+	x36 := (uint8(x35) & 0xff)
+	x37 := uint8((x35 >> 8))
+	x38 := (uint8(x7) & 0xff)
+	x39 := (x7 >> 8)
+	x40 := (uint8(x39) & 0xff)
+	x41 := (x39 >> 8)
+	x42 := (uint8(x41) & 0xff)
+	x43 := (x41 >> 8)
+	x44 := (uint8(x43) & 0xff)
+	x45 := (x43 >> 8)
+	x46 := (uint8(x45) & 0xff)
+	x47 := (x45 >> 8)
+	x48 := (uint8(x47) & 0xff)
+	x49 := (x47 >> 8)
+	x50 := (uint8(x49) & 0xff)
+	x51 := uint8((x49 >> 8))
+	x52 := (uint8(x6) & 0xff)
+	x53 := (x6 >> 8)
+	x54 := (uint8(x53) & 0xff)
+	x55 := (x53 >> 8)
+	x56 := (uint8(x55) & 0xff)
+	x57 := (x55 >> 8)
+	x58 := (uint8(x57) & 0xff)
+	x59 := (x57 >> 8)
+	x60 := (uint8(x59) & 0xff)
+	x61 := (x59 >> 8)
+	x62 := (uint8(x61) & 0xff)
+	x63 := (x61 >> 8)
+	x64 := (uint8(x63) & 0xff)
+	x65 := uint8((x63 >> 8))
+	x66 := (uint8(x5) & 0xff)
+	x67 := (x5 >> 8)
+	x68 := (uint8(x67) & 0xff)
+	x69 := (x67 >> 8)
+	x70 := (uint8(x69) & 0xff)
+	x71 := (x69 >> 8)
+	x72 := (uint8(x71) & 0xff)
+	x73 := (x71 >> 8)
+	x74 := (uint8(x73) & 0xff)
+	x75 := (x73 >> 8)
+	x76 := (uint8(x75) & 0xff)
+	x77 := (x75 >> 8)
+	x78 := (uint8(x77) & 0xff)
+	x79 := uint8((x77 >> 8))
+	x80 := (uint8(x4) & 0xff)
+	x81 := (x4 >> 8)
+	x82 := (uint8(x81) & 0xff)
+	x83 := (x81 >> 8)
+	x84 := (uint8(x83) & 0xff)
+	x85 := (x83 >> 8)
+	x86 := (uint8(x85) & 0xff)
+	x87 := (x85 >> 8)
+	x88 := (uint8(x87) & 0xff)
+	x89 := (x87 >> 8)
+	x90 := (uint8(x89) & 0xff)
+	x91 := (x89 >> 8)
+	x92 := (uint8(x91) & 0xff)
+	x93 := uint8((x91 >> 8))
+	x94 := (uint8(x3) & 0xff)
+	x95 := (x3 >> 8)
+	x96 := (uint8(x95) & 0xff)
+	x97 := (x95 >> 8)
+	x98 := (uint8(x97) & 0xff)
+	x99 := (x97 >> 8)
+	x100 := (uint8(x99) & 0xff)
+	x101 := (x99 >> 8)
+	x102 := (uint8(x101) & 0xff)
+	x103 := (x101 >> 8)
+	x104 := (uint8(x103) & 0xff)
+	x105 := (x103 >> 8)
+	x106 := (uint8(x105) & 0xff)
+	x107 := uint8((x105 >> 8))
+	x108 := (uint8(x2) & 0xff)
+	x109 := (x2 >> 8)
+	x110 := (uint8(x109) & 0xff)
+	x111 := (x109 >> 8)
+	x112 := (uint8(x111) & 0xff)
+	x113 := (x111 >> 8)
+	x114 := (uint8(x113) & 0xff)
+	x115 := (x113 >> 8)
+	x116 := (uint8(x115) & 0xff)
+	x117 := (x115 >> 8)
+	x118 := (uint8(x117) & 0xff)
+	x119 := (x117 >> 8)
+	x120 := (uint8(x119) & 0xff)
+	x121 := uint8((x119 >> 8))
+	x122 := (uint8(x1) & 0xff)
+	x123 := p521Uint1((x1 >> 8))
+	out1[0] = x10
+	out1[1] = x12
+	out1[2] = x14
+	out1[3] = x16
+	out1[4] = x18
+	out1[5] = x20
+	out1[6] = x22
+	out1[7] = x23
+	out1[8] = x24
+	out1[9] = x26
+	out1[10] = x28
+	out1[11] = x30
+	out1[12] = x32
+	out1[13] = x34
+	out1[14] = x36
+	out1[15] = x37
+	out1[16] = x38
+	out1[17] = x40
+	out1[18] = x42
+	out1[19] = x44
+	out1[20] = x46
+	out1[21] = x48
+	out1[22] = x50
+	out1[23] = x51
+	out1[24] = x52
+	out1[25] = x54
+	out1[26] = x56
+	out1[27] = x58
+	out1[28] = x60
+	out1[29] = x62
+	out1[30] = x64
+	out1[31] = x65
+	out1[32] = x66
+	out1[33] = x68
+	out1[34] = x70
+	out1[35] = x72
+	out1[36] = x74
+	out1[37] = x76
+	out1[38] = x78
+	out1[39] = x79
+	out1[40] = x80
+	out1[41] = x82
+	out1[42] = x84
+	out1[43] = x86
+	out1[44] = x88
+	out1[45] = x90
+	out1[46] = x92
+	out1[47] = x93
+	out1[48] = x94
+	out1[49] = x96
+	out1[50] = x98
+	out1[51] = x100
+	out1[52] = x102
+	out1[53] = x104
+	out1[54] = x106
+	out1[55] = x107
+	out1[56] = x108
+	out1[57] = x110
+	out1[58] = x112
+	out1[59] = x114
+	out1[60] = x116
+	out1[61] = x118
+	out1[62] = x120
+	out1[63] = x121
+	out1[64] = x122
+	out1[65] = uint8(x123)
+}
+
+// p521FromBytes deserializes a field element NOT in the Montgomery domain from bytes in little-endian order.
+//
+// Preconditions:
+//
+//	0 ≤ bytes_eval arg1 < m
+//
+// Postconditions:
+//
+//	eval out1 mod m = bytes_eval arg1 mod m
+//	0 ≤ eval out1 < m
+//
+// Input Bounds:
+//
+//	arg1: [[0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0xff], [0x0 ~> 0x1]]
+//
+// Output Bounds:
+//
+//	out1: [[0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0xffffffffffffffff], [0x0 ~> 0x1ff]]
+func p521FromBytes(out1 *[9]uint64, arg1 *[66]uint8) {
+	x1 := (uint64(p521Uint1(arg1[65])) << 8)
+	x2 := arg1[64]
+	x3 := (uint64(arg1[63]) << 56)
+	x4 := (uint64(arg1[62]) << 48)
+	x5 := (uint64(arg1[61]) << 40)
+	x6 := (uint64(arg1[60]) << 32)
+	x7 := (uint64(arg1[59]) << 24)
+	x8 := (uint64(arg1[58]) << 16)
+	x9 := (uint64(arg1[57]) << 8)
+	x10 := arg1[56]
+	x11 := (uint64(arg1[55]) << 56)
+	x12 := (uint64(arg1[54]) << 48)
+	x13 := (uint64(arg1[53]) << 40)
+	x14 := (uint64(arg1[52]) << 32)
+	x15 := (uint64(arg1[51]) << 24)
+	x16 := (uint64(arg1[50]) << 16)
+	x17 := (uint64(arg1[49]) << 8)
+	x18 := arg1[48]
+	x19 := (uint64(arg1[47]) << 56)
+	x20 := (uint64(arg1[46]) << 48)
+	x21 := (uint64(arg1[45]) << 40)
+	x22 := (uint64(arg1[44]) << 32)
+	x23 := (uint64(arg1[43]) << 24)
+	x24 := (uint64(arg1[42]) << 16)
+	x25 := (uint64(arg1[41]) << 8)
+	x26 := arg1[40]
+	x27 := (uint64(arg1[39]) << 56)
+	x28 := (uint64(arg1[38]) << 48)
+	x29 := (uint64(arg1[37]) << 40)
+	x30 := (uint64(arg1[36]) << 32)
+	x31 := (uint64(arg1[35]) << 24)
+	x32 := (uint64(arg1[34]) << 16)
+	x33 := (uint64(arg1[33]) << 8)
+	x34 := arg1[32]
+	x35 := (uint64(arg1[31]) << 56)
+	x36 := (uint64(arg1[30]) << 48)
+	x37 := (uint64(arg1[29]) << 40)
+	x38 := (uint64(arg1[28]) << 32)
+	x39 := (uint64(arg1[27]) << 24)
+	x40 := (uint64(arg1[26]) << 16)
+	x41 := (uint64(arg1[25]) << 8)
+	x42 := arg1[24]
+	x43 := (uint64(arg1[23]) << 56)
+	x44 := (uint64(arg1[22]) << 48)
+	x45 := (uint64(arg1[21]) << 40)
+	x46 := (uint64(arg1[20]) << 32)
+	x47 := (uint64(arg1[19]) << 24)
+	x48 := (uint64(arg1[18]) << 16)
+	x49 := (uint64(arg1[17]) << 8)
+	x50 := arg1[16]
+	x51 := (uint64(arg1[15]) << 56)
+	x52 := (uint64(arg1[14]) << 48)
+	x53 := (uint64(arg1[13]) << 40)
+	x54 := (uint64(arg1[12]) << 32)
+	x55 := (uint64(arg1[11]) << 24)
+	x56 := (uint64(arg1[10]) << 16)
+	x57 := (uint64(arg1[9]) << 8)
+	x58 := arg1[8]
+	x59 := (uint64(arg1[7]) << 56)
+	x60 := (uint64(arg1[6]) << 48)
+	x61 := (uint64(arg1[5]) << 40)
+	x62 := (uint64(arg1[4]) << 32)
+	x63 := (uint64(arg1[3]) << 24)
+	x64 := (uint64(arg1[2]) << 16)
+	x65 := (uint64(arg1[1]) << 8)
+	x66 := arg1[0]
+	x67 := (x65 + uint64(x66))
+	x68 := (x64 + x67)
+	x69 := (x63 + x68)
+	x70 := (x62 + x69)
+	x71 := (x61 + x70)
+	x72 := (x60 + x71)
+	x73 := (x59 + x72)
+	x74 := (x57 + uint64(x58))
+	x75 := (x56 + x74)
+	x76 := (x55 + x75)
+	x77 := (x54 + x76)
+	x78 := (x53 + x77)
+	x79 := (x52 + x78)
+	x80 := (x51 + x79)
+	x81 := (x49 + uint64(x50))
+	x82 := (x48 + x81)
+	x83 := (x47 + x82)
+	x84 := (x46 + x83)
+	x85 := (x45 + x84)
+	x86 := (x44 + x85)
+	x87 := (x43 + x86)
+	x88 := (x41 + uint64(x42))
+	x89 := (x40 + x88)
+	x90 := (x39 + x89)
+	x91 := (x38 + x90)
+	x92 := (x37 + x91)
+	x93 := (x36 + x92)
+	x94 := (x35 + x93)
+	x95 := (x33 + uint64(x34))
+	x96 := (x32 + x95)
+	x97 := (x31 + x96)
+	x98 := (x30 + x97)
+	x99 := (x29 + x98)
+	x100 := (x28 + x99)
+	x101 := (x27 + x100)
+	x102 := (x25 + uint64(x26))
+	x103 := (x24 + x102)
+	x104 := (x23 + x103)
+	x105 := (x22 + x104)
+	x106 := (x21 + x105)
+	x107 := (x20 + x106)
+	x108 := (x19 + x107)
+	x109 := (x17 + uint64(x18))
+	x110 := (x16 + x109)
+	x111 := (x15 + x110)
+	x112 := (x14 + x111)
+	x113 := (x13 + x112)
+	x114 := (x12 + x113)
+	x115 := (x11 + x114)
+	x116 := (x9 + uint64(x10))
+	x117 := (x8 + x116)
+	x118 := (x7 + x117)
+	x119 := (x6 + x118)
+	x120 := (x5 + x119)
+	x121 := (x4 + x120)
+	x122 := (x3 + x121)
+	x123 := (x1 + uint64(x2))
+	out1[0] = x73
+	out1[1] = x80
+	out1[2] = x87
+	out1[3] = x94
+	out1[4] = x101
+	out1[5] = x108
+	out1[6] = x115
+	out1[7] = x122
+	out1[8] = x123
+}
diff --git a/contrib/go/_std_1.18/src/crypto/elliptic/internal/fiat/p521_invert.go b/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p521_invert.go
index 407711af36..407711af36 100644
--- a/contrib/go/_std_1.18/src/crypto/elliptic/internal/fiat/p521_invert.go
+++ b/contrib/go/_std_1.19/src/crypto/internal/nistec/fiat/p521_invert.go
diff --git a/contrib/go/_std_1.19/src/crypto/internal/nistec/nistec.go b/contrib/go/_std_1.19/src/crypto/internal/nistec/nistec.go
new file mode 100644
index 0000000000..d898d409ca
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/internal/nistec/nistec.go
@@ -0,0 +1,15 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package nistec implements the NIST P elliptic curves from FIPS 186-4.
+//
+// This package uses fiat-crypto or specialized assembly and Go code for its
+// backend field arithmetic (not math/big) and exposes constant-time, heap
+// allocation-free, byte slice-based safe APIs. Group operations use modern and
+// safe complete addition formulas where possible. The point at infinity is
+// handled and encoded according to SEC 1, Version 2.0, and invalid curve points
+// can't be represented.
+package nistec
+
+//go:generate go run generate.go
diff --git a/contrib/go/_std_1.19/src/crypto/internal/nistec/p224.go b/contrib/go/_std_1.19/src/crypto/internal/nistec/p224.go
new file mode 100644
index 0000000000..8d236b33d7
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/internal/nistec/p224.go
@@ -0,0 +1,428 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Code generated by generate.go. DO NOT EDIT.
+
+package nistec
+
+import (
+	"crypto/internal/nistec/fiat"
+	"crypto/subtle"
+	"errors"
+	"sync"
+)
+
+var p224B, _ = new(fiat.P224Element).SetBytes([]byte{0xb4, 0x5, 0xa, 0x85, 0xc, 0x4, 0xb3, 0xab, 0xf5, 0x41, 0x32, 0x56, 0x50, 0x44, 0xb0, 0xb7, 0xd7, 0xbf, 0xd8, 0xba, 0x27, 0xb, 0x39, 0x43, 0x23, 0x55, 0xff, 0xb4})
+
+var p224G, _ = NewP224Point().SetBytes([]byte{0x4, 0xb7, 0xe, 0xc, 0xbd, 0x6b, 0xb4, 0xbf, 0x7f, 0x32, 0x13, 0x90, 0xb9, 0x4a, 0x3, 0xc1, 0xd3, 0x56, 0xc2, 0x11, 0x22, 0x34, 0x32, 0x80, 0xd6, 0x11, 0x5c, 0x1d, 0x21, 0xbd, 0x37, 0x63, 0x88, 0xb5, 0xf7, 0x23, 0xfb, 0x4c, 0x22, 0xdf, 0xe6, 0xcd, 0x43, 0x75, 0xa0, 0x5a, 0x7, 0x47, 0x64, 0x44, 0xd5, 0x81, 0x99, 0x85, 0x0, 0x7e, 0x34})
+
+// p224ElementLength is the length of an element of the base or scalar field,
+// which have the same bytes length for all NIST P curves.
+const p224ElementLength = 28
+
+// P224Point is a P224 point. The zero value is NOT valid.
+type P224Point struct {
+	// The point is represented in projective coordinates (X:Y:Z),
+	// where x = X/Z and y = Y/Z.
+	x, y, z *fiat.P224Element
+}
+
+// NewP224Point returns a new P224Point representing the point at infinity point.
+func NewP224Point() *P224Point {
+	return &P224Point{
+		x: new(fiat.P224Element),
+		y: new(fiat.P224Element).One(),
+		z: new(fiat.P224Element),
+	}
+}
+
+// NewP224Generator returns a new P224Point set to the canonical generator.
+func NewP224Generator() *P224Point {
+	return (&P224Point{
+		x: new(fiat.P224Element),
+		y: new(fiat.P224Element),
+		z: new(fiat.P224Element),
+	}).Set(p224G)
+}
+
+// Set sets p = q and returns p.
+func (p *P224Point) Set(q *P224Point) *P224Point {
+	p.x.Set(q.x)
+	p.y.Set(q.y)
+	p.z.Set(q.z)
+	return p
+}
+
+// SetBytes sets p to the compressed, uncompressed, or infinity value encoded in
+// b, as specified in SEC 1, Version 2.0, Section 2.3.4. If the point is not on
+// the curve, it returns nil and an error, and the receiver is unchanged.
+// Otherwise, it returns p.
+func (p *P224Point) SetBytes(b []byte) (*P224Point, error) {
+	switch {
+	// Point at infinity.
+	case len(b) == 1 && b[0] == 0:
+		return p.Set(NewP224Point()), nil
+
+	// Uncompressed form.
+	case len(b) == 1+2*p224ElementLength && b[0] == 4:
+		x, err := new(fiat.P224Element).SetBytes(b[1 : 1+p224ElementLength])
+		if err != nil {
+			return nil, err
+		}
+		y, err := new(fiat.P224Element).SetBytes(b[1+p224ElementLength:])
+		if err != nil {
+			return nil, err
+		}
+		if err := p224CheckOnCurve(x, y); err != nil {
+			return nil, err
+		}
+		p.x.Set(x)
+		p.y.Set(y)
+		p.z.One()
+		return p, nil
+
+	// Compressed form.
+	case len(b) == 1+p224ElementLength && (b[0] == 2 || b[0] == 3):
+		x, err := new(fiat.P224Element).SetBytes(b[1:])
+		if err != nil {
+			return nil, err
+		}
+
+		// y² = x³ - 3x + b
+		y := p224Polynomial(new(fiat.P224Element), x)
+		if !p224Sqrt(y, y) {
+			return nil, errors.New("invalid P224 compressed point encoding")
+		}
+
+		// Select the positive or negative root, as indicated by the least
+		// significant bit, based on the encoding type byte.
+		otherRoot := new(fiat.P224Element)
+		otherRoot.Sub(otherRoot, y)
+		cond := y.Bytes()[p224ElementLength-1]&1 ^ b[0]&1
+		y.Select(otherRoot, y, int(cond))
+
+		p.x.Set(x)
+		p.y.Set(y)
+		p.z.One()
+		return p, nil
+
+	default:
+		return nil, errors.New("invalid P224 point encoding")
+	}
+}
+
+// p224Polynomial sets y2 to x³ - 3x + b, and returns y2.
+func p224Polynomial(y2, x *fiat.P224Element) *fiat.P224Element {
+	y2.Square(x)
+	y2.Mul(y2, x)
+
+	threeX := new(fiat.P224Element).Add(x, x)
+	threeX.Add(threeX, x)
+
+	y2.Sub(y2, threeX)
+	return y2.Add(y2, p224B)
+}
+
+func p224CheckOnCurve(x, y *fiat.P224Element) error {
+	// y² = x³ - 3x + b
+	rhs := p224Polynomial(new(fiat.P224Element), x)
+	lhs := new(fiat.P224Element).Square(y)
+	if rhs.Equal(lhs) != 1 {
+		return errors.New("P224 point not on curve")
+	}
+	return nil
+}
+
+// Bytes returns the uncompressed or infinity encoding of p, as specified in
+// SEC 1, Version 2.0, Section 2.3.3. Note that the encoding of the point at
+// infinity is shorter than all other encodings.
+func (p *P224Point) Bytes() []byte {
+	// This function is outlined to make the allocations inline in the caller
+	// rather than happen on the heap.
+	var out [1 + 2*p224ElementLength]byte
+	return p.bytes(&out)
+}
+
+func (p *P224Point) bytes(out *[1 + 2*p224ElementLength]byte) []byte {
+	if p.z.IsZero() == 1 {
+		return append(out[:0], 0)
+	}
+
+	zinv := new(fiat.P224Element).Invert(p.z)
+	x := new(fiat.P224Element).Mul(p.x, zinv)
+	y := new(fiat.P224Element).Mul(p.y, zinv)
+
+	buf := append(out[:0], 4)
+	buf = append(buf, x.Bytes()...)
+	buf = append(buf, y.Bytes()...)
+	return buf
+}
+
+// BytesCompressed returns the compressed or infinity encoding of p, as
+// specified in SEC 1, Version 2.0, Section 2.3.3. Note that the encoding of the
+// point at infinity is shorter than all other encodings.
+func (p *P224Point) BytesCompressed() []byte {
+	// This function is outlined to make the allocations inline in the caller
+	// rather than happen on the heap.
+	var out [1 + p224ElementLength]byte
+	return p.bytesCompressed(&out)
+}
+
+func (p *P224Point) bytesCompressed(out *[1 + p224ElementLength]byte) []byte {
+	if p.z.IsZero() == 1 {
+		return append(out[:0], 0)
+	}
+
+	zinv := new(fiat.P224Element).Invert(p.z)
+	x := new(fiat.P224Element).Mul(p.x, zinv)
+	y := new(fiat.P224Element).Mul(p.y, zinv)
+
+	// Encode the sign of the y coordinate (indicated by the least significant
+	// bit) as the encoding type (2 or 3).
+	buf := append(out[:0], 2)
+	buf[0] |= y.Bytes()[p224ElementLength-1] & 1
+	buf = append(buf, x.Bytes()...)
+	return buf
+}
+
+// Add sets q = p1 + p2, and returns q. The points may overlap.
+func (q *P224Point) Add(p1, p2 *P224Point) *P224Point {
+	// Complete addition formula for a = -3 from "Complete addition formulas for
+	// prime order elliptic curves" (https://eprint.iacr.org/2015/1060), §A.2.
+
+	t0 := new(fiat.P224Element).Mul(p1.x, p2.x) // t0 := X1 * X2
+	t1 := new(fiat.P224Element).Mul(p1.y, p2.y) // t1 := Y1 * Y2
+	t2 := new(fiat.P224Element).Mul(p1.z, p2.z) // t2 := Z1 * Z2
+	t3 := new(fiat.P224Element).Add(p1.x, p1.y) // t3 := X1 + Y1
+	t4 := new(fiat.P224Element).Add(p2.x, p2.y) // t4 := X2 + Y2
+	t3.Mul(t3, t4)                              // t3 := t3 * t4
+	t4.Add(t0, t1)                              // t4 := t0 + t1
+	t3.Sub(t3, t4)                              // t3 := t3 - t4
+	t4.Add(p1.y, p1.z)                          // t4 := Y1 + Z1
+	x3 := new(fiat.P224Element).Add(p2.y, p2.z) // X3 := Y2 + Z2
+	t4.Mul(t4, x3)                              // t4 := t4 * X3
+	x3.Add(t1, t2)                              // X3 := t1 + t2
+	t4.Sub(t4, x3)                              // t4 := t4 - X3
+	x3.Add(p1.x, p1.z)                          // X3 := X1 + Z1
+	y3 := new(fiat.P224Element).Add(p2.x, p2.z) // Y3 := X2 + Z2
+	x3.Mul(x3, y3)                              // X3 := X3 * Y3
+	y3.Add(t0, t2)                              // Y3 := t0 + t2
+	y3.Sub(x3, y3)                              // Y3 := X3 - Y3
+	z3 := new(fiat.P224Element).Mul(p224B, t2)  // Z3 := b * t2
+	x3.Sub(y3, z3)                              // X3 := Y3 - Z3
+	z3.Add(x3, x3)                              // Z3 := X3 + X3
+	x3.Add(x3, z3)                              // X3 := X3 + Z3
+	z3.Sub(t1, x3)                              // Z3 := t1 - X3
+	x3.Add(t1, x3)                              // X3 := t1 + X3
+	y3.Mul(p224B, y3)                           // Y3 := b * Y3
+	t1.Add(t2, t2)                              // t1 := t2 + t2
+	t2.Add(t1, t2)                              // t2 := t1 + t2
+	y3.Sub(y3, t2)                              // Y3 := Y3 - t2
+	y3.Sub(y3, t0)                              // Y3 := Y3 - t0
+	t1.Add(y3, y3)                              // t1 := Y3 + Y3
+	y3.Add(t1, y3)                              // Y3 := t1 + Y3
+	t1.Add(t0, t0)                              // t1 := t0 + t0
+	t0.Add(t1, t0)                              // t0 := t1 + t0
+	t0.Sub(t0, t2)                              // t0 := t0 - t2
+	t1.Mul(t4, y3)                              // t1 := t4 * Y3
+	t2.Mul(t0, y3)                              // t2 := t0 * Y3
+	y3.Mul(x3, z3)                              // Y3 := X3 * Z3
+	y3.Add(y3, t2)                              // Y3 := Y3 + t2
+	x3.Mul(t3, x3)                              // X3 := t3 * X3
+	x3.Sub(x3, t1)                              // X3 := X3 - t1
+	z3.Mul(t4, z3)                              // Z3 := t4 * Z3
+	t1.Mul(t3, t0)                              // t1 := t3 * t0
+	z3.Add(z3, t1)                              // Z3 := Z3 + t1
+
+	q.x.Set(x3)
+	q.y.Set(y3)
+	q.z.Set(z3)
+	return q
+}
+
+// Double sets q = p + p, and returns q. The points may overlap.
+func (q *P224Point) Double(p *P224Point) *P224Point {
+	// Complete addition formula for a = -3 from "Complete addition formulas for
+	// prime order elliptic curves" (https://eprint.iacr.org/2015/1060), §A.2.
+
+	t0 := new(fiat.P224Element).Square(p.x)    // t0 := X ^ 2
+	t1 := new(fiat.P224Element).Square(p.y)    // t1 := Y ^ 2
+	t2 := new(fiat.P224Element).Square(p.z)    // t2 := Z ^ 2
+	t3 := new(fiat.P224Element).Mul(p.x, p.y)  // t3 := X * Y
+	t3.Add(t3, t3)                             // t3 := t3 + t3
+	z3 := new(fiat.P224Element).Mul(p.x, p.z)  // Z3 := X * Z
+	z3.Add(z3, z3)                             // Z3 := Z3 + Z3
+	y3 := new(fiat.P224Element).Mul(p224B, t2) // Y3 := b * t2
+	y3.Sub(y3, z3)                             // Y3 := Y3 - Z3
+	x3 := new(fiat.P224Element).Add(y3, y3)    // X3 := Y3 + Y3
+	y3.Add(x3, y3)                             // Y3 := X3 + Y3
+	x3.Sub(t1, y3)                             // X3 := t1 - Y3
+	y3.Add(t1, y3)                             // Y3 := t1 + Y3
+	y3.Mul(x3, y3)                             // Y3 := X3 * Y3
+	x3.Mul(x3, t3)                             // X3 := X3 * t3
+	t3.Add(t2, t2)                             // t3 := t2 + t2
+	t2.Add(t2, t3)                             // t2 := t2 + t3
+	z3.Mul(p224B, z3)                          // Z3 := b * Z3
+	z3.Sub(z3, t2)                             // Z3 := Z3 - t2
+	z3.Sub(z3, t0)                             // Z3 := Z3 - t0
+	t3.Add(z3, z3)                             // t3 := Z3 + Z3
+	z3.Add(z3, t3)                             // Z3 := Z3 + t3
+	t3.Add(t0, t0)                             // t3 := t0 + t0
+	t0.Add(t3, t0)                             // t0 := t3 + t0
+	t0.Sub(t0, t2)                             // t0 := t0 - t2
+	t0.Mul(t0, z3)                             // t0 := t0 * Z3
+	y3.Add(y3, t0)                             // Y3 := Y3 + t0
+	t0.Mul(p.y, p.z)                           // t0 := Y * Z
+	t0.Add(t0, t0)                             // t0 := t0 + t0
+	z3.Mul(t0, z3)                             // Z3 := t0 * Z3
+	x3.Sub(x3, z3)                             // X3 := X3 - Z3
+	z3.Mul(t0, t1)                             // Z3 := t0 * t1
+	z3.Add(z3, z3)                             // Z3 := Z3 + Z3
+	z3.Add(z3, z3)                             // Z3 := Z3 + Z3
+
+	q.x.Set(x3)
+	q.y.Set(y3)
+	q.z.Set(z3)
+	return q
+}
+
+// Select sets q to p1 if cond == 1, and to p2 if cond == 0.
+func (q *P224Point) Select(p1, p2 *P224Point, cond int) *P224Point {
+	q.x.Select(p1.x, p2.x, cond)
+	q.y.Select(p1.y, p2.y, cond)
+	q.z.Select(p1.z, p2.z, cond)
+	return q
+}
+
+// A p224Table holds the first 15 multiples of a point at offset -1, so [1]P
+// is at table[0], [15]P is at table[14], and [0]P is implicitly the identity
+// point.
+type p224Table [15]*P224Point
+
+// Select selects the n-th multiple of the table base point into p. It works in
+// constant time by iterating over every entry of the table. n must be in [0, 15].
+func (table *p224Table) Select(p *P224Point, n uint8) {
+	if n >= 16 {
+		panic("nistec: internal error: p224Table called with out-of-bounds value")
+	}
+	p.Set(NewP224Point())
+	for i := uint8(1); i < 16; i++ {
+		cond := subtle.ConstantTimeByteEq(i, n)
+		p.Select(table[i-1], p, cond)
+	}
+}
+
+// ScalarMult sets p = scalar * q, and returns p.
+func (p *P224Point) ScalarMult(q *P224Point, scalar []byte) (*P224Point, error) {
+	// Compute a p224Table for the base point q. The explicit NewP224Point
+	// calls get inlined, letting the allocations live on the stack.
+	var table = p224Table{NewP224Point(), NewP224Point(), NewP224Point(),
+		NewP224Point(), NewP224Point(), NewP224Point(), NewP224Point(),
+		NewP224Point(), NewP224Point(), NewP224Point(), NewP224Point(),
+		NewP224Point(), NewP224Point(), NewP224Point(), NewP224Point()}
+	table[0].Set(q)
+	for i := 1; i < 15; i += 2 {
+		table[i].Double(table[i/2])
+		table[i+1].Add(table[i], q)
+	}
+
+	// Instead of doing the classic double-and-add chain, we do it with a
+	// four-bit window: we double four times, and then add [0-15]P.
+	t := NewP224Point()
+	p.Set(NewP224Point())
+	for i, byte := range scalar {
+		// No need to double on the first iteration, as p is the identity at
+		// this point, and [N]∞ = ∞.
+		if i != 0 {
+			p.Double(p)
+			p.Double(p)
+			p.Double(p)
+			p.Double(p)
+		}
+
+		windowValue := byte >> 4
+		table.Select(t, windowValue)
+		p.Add(p, t)
+
+		p.Double(p)
+		p.Double(p)
+		p.Double(p)
+		p.Double(p)
+
+		windowValue = byte & 0b1111
+		table.Select(t, windowValue)
+		p.Add(p, t)
+	}
+
+	return p, nil
+}
+
+var p224GeneratorTable *[p224ElementLength * 2]p224Table
+var p224GeneratorTableOnce sync.Once
+
+// generatorTable returns a sequence of p224Tables. The first table contains
+// multiples of G. Each successive table is the previous table doubled four
+// times.
+func (p *P224Point) generatorTable() *[p224ElementLength * 2]p224Table {
+	p224GeneratorTableOnce.Do(func() {
+		p224GeneratorTable = new([p224ElementLength * 2]p224Table)
+		base := NewP224Generator()
+		for i := 0; i < p224ElementLength*2; i++ {
+			p224GeneratorTable[i][0] = NewP224Point().Set(base)
+			for j := 1; j < 15; j++ {
+				p224GeneratorTable[i][j] = NewP224Point().Add(p224GeneratorTable[i][j-1], base)
+			}
+			base.Double(base)
+			base.Double(base)
+			base.Double(base)
+			base.Double(base)
+		}
+	})
+	return p224GeneratorTable
+}
+
+// ScalarBaseMult sets p = scalar * B, where B is the canonical generator, and
+// returns p.
+func (p *P224Point) ScalarBaseMult(scalar []byte) (*P224Point, error) {
+	if len(scalar) != p224ElementLength {
+		return nil, errors.New("invalid scalar length")
+	}
+	tables := p.generatorTable()
+
+	// This is also a scalar multiplication with a four-bit window like in
+	// ScalarMult, but in this case the doublings are precomputed. The value
+	// [windowValue]G added at iteration k would normally get doubled
+	// (totIterations-k)×4 times, but with a larger precomputation we can
+	// instead add [2^((totIterations-k)×4)][windowValue]G and avoid the
+	// doublings between iterations.
+	t := NewP224Point()
+	p.Set(NewP224Point())
+	tableIndex := len(tables) - 1
+	for _, byte := range scalar {
+		windowValue := byte >> 4
+		tables[tableIndex].Select(t, windowValue)
+		p.Add(p, t)
+		tableIndex--
+
+		windowValue = byte & 0b1111
+		tables[tableIndex].Select(t, windowValue)
+		p.Add(p, t)
+		tableIndex--
+	}
+
+	return p, nil
+}
+
+// p224Sqrt sets e to a square root of x. If x is not a square, p224Sqrt returns
+// false and e is unchanged. e and x can overlap.
+func p224Sqrt(e, x *fiat.P224Element) (isSquare bool) {
+	candidate := new(fiat.P224Element)
+	p224SqrtCandidate(candidate, x)
+	square := new(fiat.P224Element).Square(candidate)
+	if square.Equal(x) != 1 {
+		return false
+	}
+	e.Set(candidate)
+	return true
+}
diff --git a/contrib/go/_std_1.19/src/crypto/internal/nistec/p224_sqrt.go b/contrib/go/_std_1.19/src/crypto/internal/nistec/p224_sqrt.go
new file mode 100644
index 0000000000..9a35cea6aa
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/internal/nistec/p224_sqrt.go
@@ -0,0 +1,132 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package nistec
+
+import (
+	"crypto/internal/nistec/fiat"
+	"sync"
+)
+
+var p224GG *[96]fiat.P224Element
+var p224GGOnce sync.Once
+
+var p224MinusOne = new(fiat.P224Element).Sub(
+	new(fiat.P224Element), new(fiat.P224Element).One())
+
+// p224SqrtCandidate sets r to a square root candidate for x. r and x must not overlap.
+func p224SqrtCandidate(r, x *fiat.P224Element) {
+	// Since p = 1 mod 4, we can't use the exponentiation by (p + 1) / 4 like
+	// for the other primes. Instead, implement a variation of Tonelli–Shanks.
+	// The constant-time implementation is adapted from Thomas Pornin's ecGFp5.
+	//
+	// https://github.com/pornin/ecgfp5/blob/82325b965/rust/src/field.rs#L337-L385
+
+	// p = q*2^n + 1 with q odd -> q = 2^128 - 1 and n = 96
+	// g^(2^n) = 1 -> g = 11 ^ q (where 11 is the smallest non-square)
+	// GG[j] = g^(2^j) for j = 0 to n-1
+
+	p224GGOnce.Do(func() {
+		p224GG = new([96]fiat.P224Element)
+		for i := range p224GG {
+			if i == 0 {
+				p224GG[i].SetBytes([]byte{0x6a, 0x0f, 0xec, 0x67,
+					0x85, 0x98, 0xa7, 0x92, 0x0c, 0x55, 0xb2, 0xd4,
+					0x0b, 0x2d, 0x6f, 0xfb, 0xbe, 0xa3, 0xd8, 0xce,
+					0xf3, 0xfb, 0x36, 0x32, 0xdc, 0x69, 0x1b, 0x74})
+			} else {
+				p224GG[i].Square(&p224GG[i-1])
+			}
+		}
+	})
+
+	// r <- x^((q+1)/2) = x^(2^127)
+	// v <- x^q = x^(2^128-1)
+
+	// Compute x^(2^127-1) first.
+	//
+	// The sequence of 10 multiplications and 126 squarings is derived from the
+	// following addition chain generated with github.com/mmcloughlin/addchain v0.4.0.
+	//
+	//	_10      = 2*1
+	//	_11      = 1 + _10
+	//	_110     = 2*_11
+	//	_111     = 1 + _110
+	//	_111000  = _111 << 3
+	//	_111111  = _111 + _111000
+	//	_1111110 = 2*_111111
+	//	_1111111 = 1 + _1111110
+	//	x12      = _1111110 << 5 + _111111
+	//	x24      = x12 << 12 + x12
+	//	i36      = x24 << 7
+	//	x31      = _1111111 + i36
+	//	x48      = i36 << 17 + x24
+	//	x96      = x48 << 48 + x48
+	//	return     x96 << 31 + x31
+	//
+	var t0 = new(fiat.P224Element)
+	var t1 = new(fiat.P224Element)
+
+	r.Square(x)
+	r.Mul(x, r)
+	r.Square(r)
+	r.Mul(x, r)
+	t0.Square(r)
+	for s := 1; s < 3; s++ {
+		t0.Square(t0)
+	}
+	t0.Mul(r, t0)
+	t1.Square(t0)
+	r.Mul(x, t1)
+	for s := 0; s < 5; s++ {
+		t1.Square(t1)
+	}
+	t0.Mul(t0, t1)
+	t1.Square(t0)
+	for s := 1; s < 12; s++ {
+		t1.Square(t1)
+	}
+	t0.Mul(t0, t1)
+	t1.Square(t0)
+	for s := 1; s < 7; s++ {
+		t1.Square(t1)
+	}
+	r.Mul(r, t1)
+	for s := 0; s < 17; s++ {
+		t1.Square(t1)
+	}
+	t0.Mul(t0, t1)
+	t1.Square(t0)
+	for s := 1; s < 48; s++ {
+		t1.Square(t1)
+	}
+	t0.Mul(t0, t1)
+	for s := 0; s < 31; s++ {
+		t0.Square(t0)
+	}
+	r.Mul(r, t0)
+
+	// v = x^(2^127-1)^2 * x
+	v := new(fiat.P224Element).Square(r)
+	v.Mul(v, x)
+
+	// r = x^(2^127-1) * x
+	r.Mul(r, x)
+
+	// for i = n-1 down to 1:
+	//     w = v^(2^(i-1))
+	//     if w == -1 then:
+	//         v <- v*GG[n-i]
+	//         r <- r*GG[n-i-1]
+
+	for i := 96 - 1; i >= 1; i-- {
+		w := new(fiat.P224Element).Set(v)
+		for j := 0; j < i-1; j++ {
+			w.Square(w)
+		}
+		cond := w.Equal(p224MinusOne)
+		v.Select(t0.Mul(v, &p224GG[96-i]), v, cond)
+		r.Select(t0.Mul(r, &p224GG[96-i-1]), r, cond)
+	}
+}
diff --git a/contrib/go/_std_1.19/src/crypto/internal/nistec/p256_asm.go b/contrib/go/_std_1.19/src/crypto/internal/nistec/p256_asm.go
new file mode 100644
index 0000000000..bc443ba323
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/internal/nistec/p256_asm.go
@@ -0,0 +1,704 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file contains the Go wrapper for the constant-time, 64-bit assembly
+// implementation of P256. The optimizations performed here are described in
+// detail in:
+// S.Gueron and V.Krasnov, "Fast prime field elliptic-curve cryptography with
+//                          256-bit primes"
+// https://link.springer.com/article/10.1007%2Fs13389-014-0090-x
+// https://eprint.iacr.org/2013/816.pdf
+
+//go:build amd64 || arm64 || ppc64le || s390x
+
+package nistec
+
+import (
+	_ "embed"
+	"encoding/binary"
+	"errors"
+	"math/bits"
+	"runtime"
+	"unsafe"
+)
+
+// p256Element is a P-256 base field element in [0, P-1] in the Montgomery
+// domain (with R 2²⁵⁶) as four limbs in little-endian order value.
+type p256Element [4]uint64
+
+// p256One is one in the Montgomery domain.
+var p256One = p256Element{0x0000000000000001, 0xffffffff00000000,
+	0xffffffffffffffff, 0x00000000fffffffe}
+
+var p256Zero = p256Element{}
+
+// p256P is 2²⁵⁶ - 2²²⁴ + 2¹⁹² + 2⁹⁶ - 1 in the Montgomery domain.
+var p256P = p256Element{0xffffffffffffffff, 0x00000000ffffffff,
+	0x0000000000000000, 0xffffffff00000001}
+
+// P256Point is a P-256 point. The zero value should not be assumed to be valid
+// (although it is in this implementation).
+type P256Point struct {
+	// (X:Y:Z) are Jacobian coordinates where x = X/Z² and y = Y/Z³. The point
+	// at infinity can be represented by any set of coordinates with Z = 0.
+	x, y, z p256Element
+}
+
+// NewP256Point returns a new P256Point representing the point at infinity.
+func NewP256Point() *P256Point {
+	return &P256Point{
+		x: p256One, y: p256One, z: p256Zero,
+	}
+}
+
+// NewP256Generator returns a new P256Point set to the canonical generator.
+func NewP256Generator() *P256Point {
+	return &P256Point{
+		x: p256Element{0x79e730d418a9143c, 0x75ba95fc5fedb601,
+			0x79fb732b77622510, 0x18905f76a53755c6},
+		y: p256Element{0xddf25357ce95560a, 0x8b4ab8e4ba19e45c,
+			0xd2e88688dd21f325, 0x8571ff1825885d85},
+		z: p256One,
+	}
+}
+
+// Set sets p = q and returns p.
+func (p *P256Point) Set(q *P256Point) *P256Point {
+	p.x, p.y, p.z = q.x, q.y, q.z
+	return p
+}
+
+const p256ElementLength = 32
+const p256UncompressedLength = 1 + 2*p256ElementLength
+const p256CompressedLength = 1 + p256ElementLength
+
+// SetBytes sets p to the compressed, uncompressed, or infinity value encoded in
+// b, as specified in SEC 1, Version 2.0, Section 2.3.4. If the point is not on
+// the curve, it returns nil and an error, and the receiver is unchanged.
+// Otherwise, it returns p.
+func (p *P256Point) SetBytes(b []byte) (*P256Point, error) {
+	// p256Mul operates in the Montgomery domain with R = 2²⁵⁶ mod p. Thus rr
+	// here is R in the Montgomery domain, or R×R mod p. See comment in
+	// P256OrdInverse about how this is used.
+	rr := p256Element{0x0000000000000003, 0xfffffffbffffffff,
+		0xfffffffffffffffe, 0x00000004fffffffd}
+
+	switch {
+	// Point at infinity.
+	case len(b) == 1 && b[0] == 0:
+		return p.Set(NewP256Point()), nil
+
+	// Uncompressed form.
+	case len(b) == p256UncompressedLength && b[0] == 4:
+		var r P256Point
+		p256BigToLittle(&r.x, (*[32]byte)(b[1:33]))
+		p256BigToLittle(&r.y, (*[32]byte)(b[33:65]))
+		if p256LessThanP(&r.x) == 0 || p256LessThanP(&r.y) == 0 {
+			return nil, errors.New("invalid P256 element encoding")
+		}
+		p256Mul(&r.x, &r.x, &rr)
+		p256Mul(&r.y, &r.y, &rr)
+		if err := p256CheckOnCurve(&r.x, &r.y); err != nil {
+			return nil, err
+		}
+		r.z = p256One
+		return p.Set(&r), nil
+
+	// Compressed form.
+	case len(b) == p256CompressedLength && (b[0] == 2 || b[0] == 3):
+		var r P256Point
+		p256BigToLittle(&r.x, (*[32]byte)(b[1:33]))
+		if p256LessThanP(&r.x) == 0 {
+			return nil, errors.New("invalid P256 element encoding")
+		}
+		p256Mul(&r.x, &r.x, &rr)
+
+		// y² = x³ - 3x + b
+		p256Polynomial(&r.y, &r.x)
+		if !p256Sqrt(&r.y, &r.y) {
+			return nil, errors.New("invalid P256 compressed point encoding")
+		}
+
+		// Select the positive or negative root, as indicated by the least
+		// significant bit, based on the encoding type byte.
+		yy := new(p256Element)
+		p256FromMont(yy, &r.y)
+		cond := int(yy[0]&1) ^ int(b[0]&1)
+		p256NegCond(&r.y, cond)
+
+		r.z = p256One
+		return p.Set(&r), nil
+
+	default:
+		return nil, errors.New("invalid P256 point encoding")
+	}
+}
+
+// p256Polynomial sets y2 to x³ - 3x + b, and returns y2.
+func p256Polynomial(y2, x *p256Element) *p256Element {
+	x3 := new(p256Element)
+	p256Sqr(x3, x, 1)
+	p256Mul(x3, x3, x)
+
+	threeX := new(p256Element)
+	p256Add(threeX, x, x)
+	p256Add(threeX, threeX, x)
+	p256NegCond(threeX, 1)
+
+	p256B := &p256Element{0xd89cdf6229c4bddf, 0xacf005cd78843090,
+		0xe5a220abf7212ed6, 0xdc30061d04874834}
+
+	p256Add(x3, x3, threeX)
+	p256Add(x3, x3, p256B)
+
+	*y2 = *x3
+	return y2
+}
+
+func p256CheckOnCurve(x, y *p256Element) error {
+	// y² = x³ - 3x + b
+	rhs := p256Polynomial(new(p256Element), x)
+	lhs := new(p256Element)
+	p256Sqr(lhs, y, 1)
+	if p256Equal(lhs, rhs) != 1 {
+		return errors.New("P256 point not on curve")
+	}
+	return nil
+}
+
+// p256LessThanP returns 1 if x < p, and 0 otherwise. Note that a p256Element is
+// not allowed to be equal to or greater than p, so if this function returns 0
+// then x is invalid.
+func p256LessThanP(x *p256Element) int {
+	var b uint64
+	_, b = bits.Sub64(x[0], p256P[0], b)
+	_, b = bits.Sub64(x[1], p256P[1], b)
+	_, b = bits.Sub64(x[2], p256P[2], b)
+	_, b = bits.Sub64(x[3], p256P[3], b)
+	return int(b)
+}
+
+// p256Add sets res = x + y.
+func p256Add(res, x, y *p256Element) {
+	var c, b uint64
+	t1 := make([]uint64, 4)
+	t1[0], c = bits.Add64(x[0], y[0], 0)
+	t1[1], c = bits.Add64(x[1], y[1], c)
+	t1[2], c = bits.Add64(x[2], y[2], c)
+	t1[3], c = bits.Add64(x[3], y[3], c)
+	t2 := make([]uint64, 4)
+	t2[0], b = bits.Sub64(t1[0], p256P[0], 0)
+	t2[1], b = bits.Sub64(t1[1], p256P[1], b)
+	t2[2], b = bits.Sub64(t1[2], p256P[2], b)
+	t2[3], b = bits.Sub64(t1[3], p256P[3], b)
+	// Three options:
+	//   - a+b < p
+	//     then c is 0, b is 1, and t1 is correct
+	//   - p <= a+b < 2^256
+	//     then c is 0, b is 0, and t2 is correct
+	//   - 2^256 <= a+b
+	//     then c is 1, b is 1, and t2 is correct
+	t2Mask := (c ^ b) - 1
+	res[0] = (t1[0] & ^t2Mask) | (t2[0] & t2Mask)
+	res[1] = (t1[1] & ^t2Mask) | (t2[1] & t2Mask)
+	res[2] = (t1[2] & ^t2Mask) | (t2[2] & t2Mask)
+	res[3] = (t1[3] & ^t2Mask) | (t2[3] & t2Mask)
+}
+
+// p256Sqrt sets e to a square root of x. If x is not a square, p256Sqrt returns
+// false and e is unchanged. e and x can overlap.
+func p256Sqrt(e, x *p256Element) (isSquare bool) {
+	t0, t1 := new(p256Element), new(p256Element)
+
+	// Since p = 3 mod 4, exponentiation by (p + 1) / 4 yields a square root candidate.
+	//
+	// The sequence of 7 multiplications and 253 squarings is derived from the
+	// following addition chain generated with github.com/mmcloughlin/addchain v0.4.0.
+	//
+	//	_10       = 2*1
+	//	_11       = 1 + _10
+	//	_1100     = _11 << 2
+	//	_1111     = _11 + _1100
+	//	_11110000 = _1111 << 4
+	//	_11111111 = _1111 + _11110000
+	//	x16       = _11111111 << 8 + _11111111
+	//	x32       = x16 << 16 + x16
+	//	return      ((x32 << 32 + 1) << 96 + 1) << 94
+	//
+	p256Sqr(t0, x, 1)
+	p256Mul(t0, x, t0)
+	p256Sqr(t1, t0, 2)
+	p256Mul(t0, t0, t1)
+	p256Sqr(t1, t0, 4)
+	p256Mul(t0, t0, t1)
+	p256Sqr(t1, t0, 8)
+	p256Mul(t0, t0, t1)
+	p256Sqr(t1, t0, 16)
+	p256Mul(t0, t0, t1)
+	p256Sqr(t0, t0, 32)
+	p256Mul(t0, x, t0)
+	p256Sqr(t0, t0, 96)
+	p256Mul(t0, x, t0)
+	p256Sqr(t0, t0, 94)
+
+	p256Sqr(t1, t0, 1)
+	if p256Equal(t1, x) != 1 {
+		return false
+	}
+	*e = *t0
+	return true
+}
+
+// The following assembly functions are implemented in p256_asm_*.s
+
+// Montgomery multiplication. Sets res = in1 * in2 * R⁻¹ mod p.
+//
+//go:noescape
+func p256Mul(res, in1, in2 *p256Element)
+
+// Montgomery square, repeated n times (n >= 1).
+//
+//go:noescape
+func p256Sqr(res, in *p256Element, n int)
+
+// Montgomery multiplication by R⁻¹, or 1 outside the domain.
+// Sets res = in * R⁻¹, bringing res out of the Montgomery domain.
+//
+//go:noescape
+func p256FromMont(res, in *p256Element)
+
+// If cond is not 0, sets val = -val mod p.
+//
+//go:noescape
+func p256NegCond(val *p256Element, cond int)
+
+// If cond is 0, sets res = b, otherwise sets res = a.
+//
+//go:noescape
+func p256MovCond(res, a, b *P256Point, cond int)
+
+//go:noescape
+func p256BigToLittle(res *p256Element, in *[32]byte)
+
+//go:noescape
+func p256LittleToBig(res *[32]byte, in *p256Element)
+
+//go:noescape
+func p256OrdBigToLittle(res *p256OrdElement, in *[32]byte)
+
+//go:noescape
+func p256OrdLittleToBig(res *[32]byte, in *p256OrdElement)
+
+// p256Table is a table of the first 16 multiples of a point. Points are stored
+// at an index offset of -1 so [8]P is at index 7, P is at 0, and [16]P is at 15.
+// [0]P is the point at infinity and it's not stored.
+type p256Table [16]P256Point
+
+// p256Select sets res to the point at index idx in the table.
+// idx must be in [0, 15]. It executes in constant time.
+//
+//go:noescape
+func p256Select(res *P256Point, table *p256Table, idx int)
+
+// p256AffinePoint is a point in affine coordinates (x, y). x and y are still
+// Montgomery domain elements. The point can't be the point at infinity.
+type p256AffinePoint struct {
+	x, y p256Element
+}
+
+// p256AffineTable is a table of the first 32 multiples of a point. Points are
+// stored at an index offset of -1 like in p256Table, and [0]P is not stored.
+type p256AffineTable [32]p256AffinePoint
+
+// p256Precomputed is a series of precomputed multiples of G, the canonical
+// generator. The first p256AffineTable contains multiples of G. The second one
+// multiples of [2⁶]G, the third one of [2¹²]G, and so on, where each successive
+// table is the previous table doubled six times. Six is the width of the
+// sliding window used in p256ScalarMult, and having each table already
+// pre-doubled lets us avoid the doublings between windows entirely. This table
+// MUST NOT be modified, as it aliases into p256PrecomputedEmbed below.
+var p256Precomputed *[43]p256AffineTable
+
+//go:embed p256_asm_table.bin
+var p256PrecomputedEmbed string
+
+func init() {
+	p256PrecomputedPtr := (*unsafe.Pointer)(unsafe.Pointer(&p256PrecomputedEmbed))
+	if runtime.GOARCH == "s390x" {
+		var newTable [43 * 32 * 2 * 4]uint64
+		for i, x := range (*[43 * 32 * 2 * 4][8]byte)(*p256PrecomputedPtr) {
+			newTable[i] = binary.LittleEndian.Uint64(x[:])
+		}
+		newTablePtr := unsafe.Pointer(&newTable)
+		p256PrecomputedPtr = &newTablePtr
+	}
+	p256Precomputed = (*[43]p256AffineTable)(*p256PrecomputedPtr)
+}
+
+// p256SelectAffine sets res to the point at index idx in the table.
+// idx must be in [0, 31]. It executes in constant time.
+//
+//go:noescape
+func p256SelectAffine(res *p256AffinePoint, table *p256AffineTable, idx int)
+
+// Point addition with an affine point and constant time conditions.
+// If zero is 0, sets res = in2. If sel is 0, sets res = in1.
+// If sign is not 0, sets res = in1 + -in2. Otherwise, sets res = in1 + in2
+//
+//go:noescape
+func p256PointAddAffineAsm(res, in1 *P256Point, in2 *p256AffinePoint, sign, sel, zero int)
+
+// Point addition. Sets res = in1 + in2. Returns one if the two input points
+// were equal and zero otherwise. If in1 or in2 are the point at infinity, res
+// and the return value are undefined.
+//
+//go:noescape
+func p256PointAddAsm(res, in1, in2 *P256Point) int
+
+// Point doubling. Sets res = in + in. in can be the point at infinity.
+//
+//go:noescape
+func p256PointDoubleAsm(res, in *P256Point)
+
+// p256OrdElement is a P-256 scalar field element in [0, ord(G)-1] in the
+// Montgomery domain (with R 2²⁵⁶) as four uint64 limbs in little-endian order.
+type p256OrdElement [4]uint64
+
+// Add sets q = p1 + p2, and returns q. The points may overlap.
+func (q *P256Point) Add(r1, r2 *P256Point) *P256Point {
+	var sum, double P256Point
+	r1IsInfinity := r1.isInfinity()
+	r2IsInfinity := r2.isInfinity()
+	pointsEqual := p256PointAddAsm(&sum, r1, r2)
+	p256PointDoubleAsm(&double, r1)
+	p256MovCond(&sum, &double, &sum, pointsEqual)
+	p256MovCond(&sum, r1, &sum, r2IsInfinity)
+	p256MovCond(&sum, r2, &sum, r1IsInfinity)
+	return q.Set(&sum)
+}
+
+// Double sets q = p + p, and returns q. The points may overlap.
+func (q *P256Point) Double(p *P256Point) *P256Point {
+	var double P256Point
+	p256PointDoubleAsm(&double, p)
+	return q.Set(&double)
+}
+
+// ScalarBaseMult sets r = scalar * generator, where scalar is a 32-byte big
+// endian value, and returns r. If scalar is not 32 bytes long, ScalarBaseMult
+// returns an error and the receiver is unchanged.
+func (r *P256Point) ScalarBaseMult(scalar []byte) (*P256Point, error) {
+	if len(scalar) != 32 {
+		return nil, errors.New("invalid scalar length")
+	}
+	scalarReversed := new(p256OrdElement)
+	p256OrdBigToLittle(scalarReversed, (*[32]byte)(scalar))
+
+	r.p256BaseMult(scalarReversed)
+	return r, nil
+}
+
+// ScalarMult sets r = scalar * q, where scalar is a 32-byte big endian value,
+// and returns r. If scalar is not 32 bytes long, ScalarBaseMult returns an
+// error and the receiver is unchanged.
+func (r *P256Point) ScalarMult(q *P256Point, scalar []byte) (*P256Point, error) {
+	if len(scalar) != 32 {
+		return nil, errors.New("invalid scalar length")
+	}
+	scalarReversed := new(p256OrdElement)
+	p256OrdBigToLittle(scalarReversed, (*[32]byte)(scalar))
+
+	r.Set(q).p256ScalarMult(scalarReversed)
+	return r, nil
+}
+
+// uint64IsZero returns 1 if x is zero and zero otherwise.
+func uint64IsZero(x uint64) int {
+	x = ^x
+	x &= x >> 32
+	x &= x >> 16
+	x &= x >> 8
+	x &= x >> 4
+	x &= x >> 2
+	x &= x >> 1
+	return int(x & 1)
+}
+
+// p256Equal returns 1 if a and b are equal and 0 otherwise.
+func p256Equal(a, b *p256Element) int {
+	var acc uint64
+	for i := range a {
+		acc |= a[i] ^ b[i]
+	}
+	return uint64IsZero(acc)
+}
+
+// isInfinity returns 1 if p is the point at infinity and 0 otherwise.
+func (p *P256Point) isInfinity() int {
+	return p256Equal(&p.z, &p256Zero)
+}
+
+// Bytes returns the uncompressed or infinity encoding of p, as specified in
+// SEC 1, Version 2.0, Section 2.3.3. Note that the encoding of the point at
+// infinity is shorter than all other encodings.
+func (p *P256Point) Bytes() []byte {
+	// This function is outlined to make the allocations inline in the caller
+	// rather than happen on the heap.
+	var out [p256UncompressedLength]byte
+	return p.bytes(&out)
+}
+
+func (p *P256Point) bytes(out *[p256UncompressedLength]byte) []byte {
+	// The proper representation of the point at infinity is a single zero byte.
+	if p.isInfinity() == 1 {
+		return append(out[:0], 0)
+	}
+
+	x, y := new(p256Element), new(p256Element)
+	p.affineFromMont(x, y)
+
+	out[0] = 4 // Uncompressed form.
+	p256LittleToBig((*[32]byte)(out[1:33]), x)
+	p256LittleToBig((*[32]byte)(out[33:65]), y)
+
+	return out[:]
+}
+
+// affineFromMont sets (x, y) to the affine coordinates of p, converted out of the
+// Montgomery domain.
+func (p *P256Point) affineFromMont(x, y *p256Element) {
+	p256Inverse(y, &p.z)
+	p256Sqr(x, y, 1)
+	p256Mul(y, y, x)
+
+	p256Mul(x, &p.x, x)
+	p256Mul(y, &p.y, y)
+
+	p256FromMont(x, x)
+	p256FromMont(y, y)
+}
+
+// BytesCompressed returns the compressed or infinity encoding of p, as
+// specified in SEC 1, Version 2.0, Section 2.3.3. Note that the encoding of the
+// point at infinity is shorter than all other encodings.
+func (p *P256Point) BytesCompressed() []byte {
+	// This function is outlined to make the allocations inline in the caller
+	// rather than happen on the heap.
+	var out [p256CompressedLength]byte
+	return p.bytesCompressed(&out)
+}
+
+func (p *P256Point) bytesCompressed(out *[p256CompressedLength]byte) []byte {
+	if p.isInfinity() == 1 {
+		return append(out[:0], 0)
+	}
+
+	x, y := new(p256Element), new(p256Element)
+	p.affineFromMont(x, y)
+
+	out[0] = 2 | byte(y[0]&1)
+	p256LittleToBig((*[32]byte)(out[1:33]), x)
+
+	return out[:]
+}
+
+// Select sets q to p1 if cond == 1, and to p2 if cond == 0.
+func (q *P256Point) Select(p1, p2 *P256Point, cond int) *P256Point {
+	p256MovCond(q, p1, p2, cond)
+	return q
+}
+
+// p256Inverse sets out to in⁻¹ mod p. If in is zero, out will be zero.
+func p256Inverse(out, in *p256Element) {
+	// Inversion is calculated through exponentiation by p - 2, per Fermat's
+	// little theorem.
+	//
+	// The sequence of 12 multiplications and 255 squarings is derived from the
+	// following addition chain generated with github.com/mmcloughlin/addchain
+	// v0.4.0.
+	//
+	//  _10     = 2*1
+	//  _11     = 1 + _10
+	//  _110    = 2*_11
+	//  _111    = 1 + _110
+	//  _111000 = _111 << 3
+	//  _111111 = _111 + _111000
+	//  x12     = _111111 << 6 + _111111
+	//  x15     = x12 << 3 + _111
+	//  x16     = 2*x15 + 1
+	//  x32     = x16 << 16 + x16
+	//  i53     = x32 << 15
+	//  x47     = x15 + i53
+	//  i263    = ((i53 << 17 + 1) << 143 + x47) << 47
+	//  return    (x47 + i263) << 2 + 1
+	//
+	var z = new(p256Element)
+	var t0 = new(p256Element)
+	var t1 = new(p256Element)
+
+	p256Sqr(z, in, 1)
+	p256Mul(z, in, z)
+	p256Sqr(z, z, 1)
+	p256Mul(z, in, z)
+	p256Sqr(t0, z, 3)
+	p256Mul(t0, z, t0)
+	p256Sqr(t1, t0, 6)
+	p256Mul(t0, t0, t1)
+	p256Sqr(t0, t0, 3)
+	p256Mul(z, z, t0)
+	p256Sqr(t0, z, 1)
+	p256Mul(t0, in, t0)
+	p256Sqr(t1, t0, 16)
+	p256Mul(t0, t0, t1)
+	p256Sqr(t0, t0, 15)
+	p256Mul(z, z, t0)
+	p256Sqr(t0, t0, 17)
+	p256Mul(t0, in, t0)
+	p256Sqr(t0, t0, 143)
+	p256Mul(t0, z, t0)
+	p256Sqr(t0, t0, 47)
+	p256Mul(z, z, t0)
+	p256Sqr(z, z, 2)
+	p256Mul(out, in, z)
+}
+
+func boothW5(in uint) (int, int) {
+	var s uint = ^((in >> 5) - 1)
+	var d uint = (1 << 6) - in - 1
+	d = (d & s) | (in & (^s))
+	d = (d >> 1) + (d & 1)
+	return int(d), int(s & 1)
+}
+
+func boothW6(in uint) (int, int) {
+	var s uint = ^((in >> 6) - 1)
+	var d uint = (1 << 7) - in - 1
+	d = (d & s) | (in & (^s))
+	d = (d >> 1) + (d & 1)
+	return int(d), int(s & 1)
+}
+
+func (p *P256Point) p256BaseMult(scalar *p256OrdElement) {
+	var t0 p256AffinePoint
+
+	wvalue := (scalar[0] << 1) & 0x7f
+	sel, sign := boothW6(uint(wvalue))
+	p256SelectAffine(&t0, &p256Precomputed[0], sel)
+	p.x, p.y, p.z = t0.x, t0.y, p256One
+	p256NegCond(&p.y, sign)
+
+	index := uint(5)
+	zero := sel
+
+	for i := 1; i < 43; i++ {
+		if index < 192 {
+			wvalue = ((scalar[index/64] >> (index % 64)) + (scalar[index/64+1] << (64 - (index % 64)))) & 0x7f
+		} else {
+			wvalue = (scalar[index/64] >> (index % 64)) & 0x7f
+		}
+		index += 6
+		sel, sign = boothW6(uint(wvalue))
+		p256SelectAffine(&t0, &p256Precomputed[i], sel)
+		p256PointAddAffineAsm(p, p, &t0, sign, sel, zero)
+		zero |= sel
+	}
+
+	// If the whole scalar was zero, set to the point at infinity.
+	p256MovCond(p, p, NewP256Point(), zero)
+}
+
+func (p *P256Point) p256ScalarMult(scalar *p256OrdElement) {
+	// precomp is a table of precomputed points that stores powers of p
+	// from p^1 to p^16.
+	var precomp p256Table
+	var t0, t1, t2, t3 P256Point
+
+	// Prepare the table
+	precomp[0] = *p // 1
+
+	p256PointDoubleAsm(&t0, p)
+	p256PointDoubleAsm(&t1, &t0)
+	p256PointDoubleAsm(&t2, &t1)
+	p256PointDoubleAsm(&t3, &t2)
+	precomp[1] = t0  // 2
+	precomp[3] = t1  // 4
+	precomp[7] = t2  // 8
+	precomp[15] = t3 // 16
+
+	p256PointAddAsm(&t0, &t0, p)
+	p256PointAddAsm(&t1, &t1, p)
+	p256PointAddAsm(&t2, &t2, p)
+	precomp[2] = t0 // 3
+	precomp[4] = t1 // 5
+	precomp[8] = t2 // 9
+
+	p256PointDoubleAsm(&t0, &t0)
+	p256PointDoubleAsm(&t1, &t1)
+	precomp[5] = t0 // 6
+	precomp[9] = t1 // 10
+
+	p256PointAddAsm(&t2, &t0, p)
+	p256PointAddAsm(&t1, &t1, p)
+	precomp[6] = t2  // 7
+	precomp[10] = t1 // 11
+
+	p256PointDoubleAsm(&t0, &t0)
+	p256PointDoubleAsm(&t2, &t2)
+	precomp[11] = t0 // 12
+	precomp[13] = t2 // 14
+
+	p256PointAddAsm(&t0, &t0, p)
+	p256PointAddAsm(&t2, &t2, p)
+	precomp[12] = t0 // 13
+	precomp[14] = t2 // 15
+
+	// Start scanning the window from top bit
+	index := uint(254)
+	var sel, sign int
+
+	wvalue := (scalar[index/64] >> (index % 64)) & 0x3f
+	sel, _ = boothW5(uint(wvalue))
+
+	p256Select(p, &precomp, sel)
+	zero := sel
+
+	for index > 4 {
+		index -= 5
+		p256PointDoubleAsm(p, p)
+		p256PointDoubleAsm(p, p)
+		p256PointDoubleAsm(p, p)
+		p256PointDoubleAsm(p, p)
+		p256PointDoubleAsm(p, p)
+
+		if index < 192 {
+			wvalue = ((scalar[index/64] >> (index % 64)) + (scalar[index/64+1] << (64 - (index % 64)))) & 0x3f
+		} else {
+			wvalue = (scalar[index/64] >> (index % 64)) & 0x3f
+		}
+
+		sel, sign = boothW5(uint(wvalue))
+
+		p256Select(&t0, &precomp, sel)
+		p256NegCond(&t0.y, sign)
+		p256PointAddAsm(&t1, p, &t0)
+		p256MovCond(&t1, &t1, p, sel)
+		p256MovCond(p, &t1, &t0, zero)
+		zero |= sel
+	}
+
+	p256PointDoubleAsm(p, p)
+	p256PointDoubleAsm(p, p)
+	p256PointDoubleAsm(p, p)
+	p256PointDoubleAsm(p, p)
+	p256PointDoubleAsm(p, p)
+
+	wvalue = (scalar[0] << 1) & 0x3f
+	sel, sign = boothW5(uint(wvalue))
+
+	p256Select(&t0, &precomp, sel)
+	p256NegCond(&t0.y, sign)
+	p256PointAddAsm(&t1, p, &t0)
+	p256MovCond(&t1, &t1, p, sel)
+	p256MovCond(p, &t1, &t0, zero)
+}
diff --git a/contrib/go/_std_1.19/src/crypto/internal/nistec/p256_asm_amd64.s b/contrib/go/_std_1.19/src/crypto/internal/nistec/p256_asm_amd64.s
new file mode 100644
index 0000000000..84e4cee903
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/internal/nistec/p256_asm_amd64.s
@@ -0,0 +1,2350 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file contains constant-time, 64-bit assembly implementation of
+// P256. The optimizations performed here are described in detail in:
+// S.Gueron and V.Krasnov, "Fast prime field elliptic-curve cryptography with
+//                          256-bit primes"
+// https://link.springer.com/article/10.1007%2Fs13389-014-0090-x
+// https://eprint.iacr.org/2013/816.pdf
+
+#include "textflag.h"
+
+#define res_ptr DI
+#define x_ptr SI
+#define y_ptr CX
+
+#define acc0 R8
+#define acc1 R9
+#define acc2 R10
+#define acc3 R11
+#define acc4 R12
+#define acc5 R13
+#define t0 R14
+#define t1 R15
+
+DATA p256const0<>+0x00(SB)/8, $0x00000000ffffffff
+DATA p256const1<>+0x00(SB)/8, $0xffffffff00000001
+DATA p256ordK0<>+0x00(SB)/8, $0xccd1c8aaee00bc4f
+DATA p256ord<>+0x00(SB)/8, $0xf3b9cac2fc632551
+DATA p256ord<>+0x08(SB)/8, $0xbce6faada7179e84
+DATA p256ord<>+0x10(SB)/8, $0xffffffffffffffff
+DATA p256ord<>+0x18(SB)/8, $0xffffffff00000000
+DATA p256one<>+0x00(SB)/8, $0x0000000000000001
+DATA p256one<>+0x08(SB)/8, $0xffffffff00000000
+DATA p256one<>+0x10(SB)/8, $0xffffffffffffffff
+DATA p256one<>+0x18(SB)/8, $0x00000000fffffffe
+GLOBL p256const0<>(SB), 8, $8
+GLOBL p256const1<>(SB), 8, $8
+GLOBL p256ordK0<>(SB), 8, $8
+GLOBL p256ord<>(SB), 8, $32
+GLOBL p256one<>(SB), 8, $32
+
+/* ---------------------------------------*/
+// func p256OrdLittleToBig(res *[32]byte, in *p256OrdElement)
+TEXT ·p256OrdLittleToBig(SB),NOSPLIT,$0
+	JMP ·p256BigToLittle(SB)
+/* ---------------------------------------*/
+// func p256OrdBigToLittle(res *p256OrdElement, in *[32]byte)
+TEXT ·p256OrdBigToLittle(SB),NOSPLIT,$0
+	JMP ·p256BigToLittle(SB)
+/* ---------------------------------------*/
+// func p256LittleToBig(res *[32]byte, in *p256Element)
+TEXT ·p256LittleToBig(SB),NOSPLIT,$0
+	JMP ·p256BigToLittle(SB)
+/* ---------------------------------------*/
+// func p256BigToLittle(res *p256Element, in *[32]byte)
+TEXT ·p256BigToLittle(SB),NOSPLIT,$0
+	MOVQ res+0(FP), res_ptr
+	MOVQ in+8(FP), x_ptr
+
+	MOVQ (8*0)(x_ptr), acc0
+	MOVQ (8*1)(x_ptr), acc1
+	MOVQ (8*2)(x_ptr), acc2
+	MOVQ (8*3)(x_ptr), acc3
+
+	BSWAPQ acc0
+	BSWAPQ acc1
+	BSWAPQ acc2
+	BSWAPQ acc3
+
+	MOVQ acc3, (8*0)(res_ptr)
+	MOVQ acc2, (8*1)(res_ptr)
+	MOVQ acc1, (8*2)(res_ptr)
+	MOVQ acc0, (8*3)(res_ptr)
+
+	RET
+/* ---------------------------------------*/
+// func p256MovCond(res, a, b *P256Point, cond int)
+TEXT ·p256MovCond(SB),NOSPLIT,$0
+	MOVQ res+0(FP), res_ptr
+	MOVQ a+8(FP), x_ptr
+	MOVQ b+16(FP), y_ptr
+	MOVQ cond+24(FP), X12
+
+	PXOR X13, X13
+	PSHUFD $0, X12, X12
+	PCMPEQL X13, X12
+
+	MOVOU X12, X0
+	MOVOU (16*0)(x_ptr), X6
+	PANDN X6, X0
+	MOVOU X12, X1
+	MOVOU (16*1)(x_ptr), X7
+	PANDN X7, X1
+	MOVOU X12, X2
+	MOVOU (16*2)(x_ptr), X8
+	PANDN X8, X2
+	MOVOU X12, X3
+	MOVOU (16*3)(x_ptr), X9
+	PANDN X9, X3
+	MOVOU X12, X4
+	MOVOU (16*4)(x_ptr), X10
+	PANDN X10, X4
+	MOVOU X12, X5
+	MOVOU (16*5)(x_ptr), X11
+	PANDN X11, X5
+
+	MOVOU (16*0)(y_ptr), X6
+	MOVOU (16*1)(y_ptr), X7
+	MOVOU (16*2)(y_ptr), X8
+	MOVOU (16*3)(y_ptr), X9
+	MOVOU (16*4)(y_ptr), X10
+	MOVOU (16*5)(y_ptr), X11
+
+	PAND X12, X6
+	PAND X12, X7
+	PAND X12, X8
+	PAND X12, X9
+	PAND X12, X10
+	PAND X12, X11
+
+	PXOR X6, X0
+	PXOR X7, X1
+	PXOR X8, X2
+	PXOR X9, X3
+	PXOR X10, X4
+	PXOR X11, X5
+
+	MOVOU X0, (16*0)(res_ptr)
+	MOVOU X1, (16*1)(res_ptr)
+	MOVOU X2, (16*2)(res_ptr)
+	MOVOU X3, (16*3)(res_ptr)
+	MOVOU X4, (16*4)(res_ptr)
+	MOVOU X5, (16*5)(res_ptr)
+
+	RET
+/* ---------------------------------------*/
+// func p256NegCond(val *p256Element, cond int)
+TEXT ·p256NegCond(SB),NOSPLIT,$0
+	MOVQ val+0(FP), res_ptr
+	MOVQ cond+8(FP), t0
+	// acc = poly
+	MOVQ $-1, acc0
+	MOVQ p256const0<>(SB), acc1
+	MOVQ $0, acc2
+	MOVQ p256const1<>(SB), acc3
+	// Load the original value
+	MOVQ (8*0)(res_ptr), acc5
+	MOVQ (8*1)(res_ptr), x_ptr
+	MOVQ (8*2)(res_ptr), y_ptr
+	MOVQ (8*3)(res_ptr), t1
+	// Speculatively subtract
+	SUBQ acc5, acc0
+	SBBQ x_ptr, acc1
+	SBBQ y_ptr, acc2
+	SBBQ t1, acc3
+	// If condition is 0, keep original value
+	TESTQ t0, t0
+	CMOVQEQ acc5, acc0
+	CMOVQEQ x_ptr, acc1
+	CMOVQEQ y_ptr, acc2
+	CMOVQEQ t1, acc3
+	// Store result
+	MOVQ acc0, (8*0)(res_ptr)
+	MOVQ acc1, (8*1)(res_ptr)
+	MOVQ acc2, (8*2)(res_ptr)
+	MOVQ acc3, (8*3)(res_ptr)
+
+	RET
+/* ---------------------------------------*/
+// func p256Sqr(res, in *p256Element, n int)
+TEXT ·p256Sqr(SB),NOSPLIT,$0
+	MOVQ res+0(FP), res_ptr
+	MOVQ in+8(FP), x_ptr
+	MOVQ n+16(FP), BX
+
+sqrLoop:
+
+	// y[1:] * y[0]
+	MOVQ (8*0)(x_ptr), t0
+
+	MOVQ (8*1)(x_ptr), AX
+	MULQ t0
+	MOVQ AX, acc1
+	MOVQ DX, acc2
+
+	MOVQ (8*2)(x_ptr), AX
+	MULQ t0
+	ADDQ AX, acc2
+	ADCQ $0, DX
+	MOVQ DX, acc3
+
+	MOVQ (8*3)(x_ptr), AX
+	MULQ t0
+	ADDQ AX, acc3
+	ADCQ $0, DX
+	MOVQ DX, acc4
+	// y[2:] * y[1]
+	MOVQ (8*1)(x_ptr), t0
+
+	MOVQ (8*2)(x_ptr), AX
+	MULQ t0
+	ADDQ AX, acc3
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ (8*3)(x_ptr), AX
+	MULQ t0
+	ADDQ t1, acc4
+	ADCQ $0, DX
+	ADDQ AX, acc4
+	ADCQ $0, DX
+	MOVQ DX, acc5
+	// y[3] * y[2]
+	MOVQ (8*2)(x_ptr), t0
+
+	MOVQ (8*3)(x_ptr), AX
+	MULQ t0
+	ADDQ AX, acc5
+	ADCQ $0, DX
+	MOVQ DX, y_ptr
+	XORQ t1, t1
+	// *2
+	ADDQ acc1, acc1
+	ADCQ acc2, acc2
+	ADCQ acc3, acc3
+	ADCQ acc4, acc4
+	ADCQ acc5, acc5
+	ADCQ y_ptr, y_ptr
+	ADCQ $0, t1
+	// Missing products
+	MOVQ (8*0)(x_ptr), AX
+	MULQ AX
+	MOVQ AX, acc0
+	MOVQ DX, t0
+
+	MOVQ (8*1)(x_ptr), AX
+	MULQ AX
+	ADDQ t0, acc1
+	ADCQ AX, acc2
+	ADCQ $0, DX
+	MOVQ DX, t0
+
+	MOVQ (8*2)(x_ptr), AX
+	MULQ AX
+	ADDQ t0, acc3
+	ADCQ AX, acc4
+	ADCQ $0, DX
+	MOVQ DX, t0
+
+	MOVQ (8*3)(x_ptr), AX
+	MULQ AX
+	ADDQ t0, acc5
+	ADCQ AX, y_ptr
+	ADCQ DX, t1
+	MOVQ t1, x_ptr
+	// First reduction step
+	MOVQ acc0, AX
+	MOVQ acc0, t1
+	SHLQ $32, acc0
+	MULQ p256const1<>(SB)
+	SHRQ $32, t1
+	ADDQ acc0, acc1
+	ADCQ t1, acc2
+	ADCQ AX, acc3
+	ADCQ $0, DX
+	MOVQ DX, acc0
+	// Second reduction step
+	MOVQ acc1, AX
+	MOVQ acc1, t1
+	SHLQ $32, acc1
+	MULQ p256const1<>(SB)
+	SHRQ $32, t1
+	ADDQ acc1, acc2
+	ADCQ t1, acc3
+	ADCQ AX, acc0
+	ADCQ $0, DX
+	MOVQ DX, acc1
+	// Third reduction step
+	MOVQ acc2, AX
+	MOVQ acc2, t1
+	SHLQ $32, acc2
+	MULQ p256const1<>(SB)
+	SHRQ $32, t1
+	ADDQ acc2, acc3
+	ADCQ t1, acc0
+	ADCQ AX, acc1
+	ADCQ $0, DX
+	MOVQ DX, acc2
+	// Last reduction step
+	XORQ t0, t0
+	MOVQ acc3, AX
+	MOVQ acc3, t1
+	SHLQ $32, acc3
+	MULQ p256const1<>(SB)
+	SHRQ $32, t1
+	ADDQ acc3, acc0
+	ADCQ t1, acc1
+	ADCQ AX, acc2
+	ADCQ $0, DX
+	MOVQ DX, acc3
+	// Add bits [511:256] of the sqr result
+	ADCQ acc4, acc0
+	ADCQ acc5, acc1
+	ADCQ y_ptr, acc2
+	ADCQ x_ptr, acc3
+	ADCQ $0, t0
+
+	MOVQ acc0, acc4
+	MOVQ acc1, acc5
+	MOVQ acc2, y_ptr
+	MOVQ acc3, t1
+	// Subtract p256
+	SUBQ $-1, acc0
+	SBBQ p256const0<>(SB) ,acc1
+	SBBQ $0, acc2
+	SBBQ p256const1<>(SB), acc3
+	SBBQ $0, t0
+
+	CMOVQCS acc4, acc0
+	CMOVQCS acc5, acc1
+	CMOVQCS y_ptr, acc2
+	CMOVQCS t1, acc3
+
+	MOVQ acc0, (8*0)(res_ptr)
+	MOVQ acc1, (8*1)(res_ptr)
+	MOVQ acc2, (8*2)(res_ptr)
+	MOVQ acc3, (8*3)(res_ptr)
+	MOVQ res_ptr, x_ptr
+	DECQ BX
+	JNE  sqrLoop
+
+	RET
+/* ---------------------------------------*/
+// func p256Mul(res, in1, in2 *p256Element)
+TEXT ·p256Mul(SB),NOSPLIT,$0
+	MOVQ res+0(FP), res_ptr
+	MOVQ in1+8(FP), x_ptr
+	MOVQ in2+16(FP), y_ptr
+	// x * y[0]
+	MOVQ (8*0)(y_ptr), t0
+
+	MOVQ (8*0)(x_ptr), AX
+	MULQ t0
+	MOVQ AX, acc0
+	MOVQ DX, acc1
+
+	MOVQ (8*1)(x_ptr), AX
+	MULQ t0
+	ADDQ AX, acc1
+	ADCQ $0, DX
+	MOVQ DX, acc2
+
+	MOVQ (8*2)(x_ptr), AX
+	MULQ t0
+	ADDQ AX, acc2
+	ADCQ $0, DX
+	MOVQ DX, acc3
+
+	MOVQ (8*3)(x_ptr), AX
+	MULQ t0
+	ADDQ AX, acc3
+	ADCQ $0, DX
+	MOVQ DX, acc4
+	XORQ acc5, acc5
+	// First reduction step
+	MOVQ acc0, AX
+	MOVQ acc0, t1
+	SHLQ $32, acc0
+	MULQ p256const1<>(SB)
+	SHRQ $32, t1
+	ADDQ acc0, acc1
+	ADCQ t1, acc2
+	ADCQ AX, acc3
+	ADCQ DX, acc4
+	ADCQ $0, acc5
+	XORQ acc0, acc0
+	// x * y[1]
+	MOVQ (8*1)(y_ptr), t0
+
+	MOVQ (8*0)(x_ptr), AX
+	MULQ t0
+	ADDQ AX, acc1
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ (8*1)(x_ptr), AX
+	MULQ t0
+	ADDQ t1, acc2
+	ADCQ $0, DX
+	ADDQ AX, acc2
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ (8*2)(x_ptr), AX
+	MULQ t0
+	ADDQ t1, acc3
+	ADCQ $0, DX
+	ADDQ AX, acc3
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ (8*3)(x_ptr), AX
+	MULQ t0
+	ADDQ t1, acc4
+	ADCQ $0, DX
+	ADDQ AX, acc4
+	ADCQ DX, acc5
+	ADCQ $0, acc0
+	// Second reduction step
+	MOVQ acc1, AX
+	MOVQ acc1, t1
+	SHLQ $32, acc1
+	MULQ p256const1<>(SB)
+	SHRQ $32, t1
+	ADDQ acc1, acc2
+	ADCQ t1, acc3
+	ADCQ AX, acc4
+	ADCQ DX, acc5
+	ADCQ $0, acc0
+	XORQ acc1, acc1
+	// x * y[2]
+	MOVQ (8*2)(y_ptr), t0
+
+	MOVQ (8*0)(x_ptr), AX
+	MULQ t0
+	ADDQ AX, acc2
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ (8*1)(x_ptr), AX
+	MULQ t0
+	ADDQ t1, acc3
+	ADCQ $0, DX
+	ADDQ AX, acc3
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ (8*2)(x_ptr), AX
+	MULQ t0
+	ADDQ t1, acc4
+	ADCQ $0, DX
+	ADDQ AX, acc4
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ (8*3)(x_ptr), AX
+	MULQ t0
+	ADDQ t1, acc5
+	ADCQ $0, DX
+	ADDQ AX, acc5
+	ADCQ DX, acc0
+	ADCQ $0, acc1
+	// Third reduction step
+	MOVQ acc2, AX
+	MOVQ acc2, t1
+	SHLQ $32, acc2
+	MULQ p256const1<>(SB)
+	SHRQ $32, t1
+	ADDQ acc2, acc3
+	ADCQ t1, acc4
+	ADCQ AX, acc5
+	ADCQ DX, acc0
+	ADCQ $0, acc1
+	XORQ acc2, acc2
+	// x * y[3]
+	MOVQ (8*3)(y_ptr), t0
+
+	MOVQ (8*0)(x_ptr), AX
+	MULQ t0
+	ADDQ AX, acc3
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ (8*1)(x_ptr), AX
+	MULQ t0
+	ADDQ t1, acc4
+	ADCQ $0, DX
+	ADDQ AX, acc4
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ (8*2)(x_ptr), AX
+	MULQ t0
+	ADDQ t1, acc5
+	ADCQ $0, DX
+	ADDQ AX, acc5
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ (8*3)(x_ptr), AX
+	MULQ t0
+	ADDQ t1, acc0
+	ADCQ $0, DX
+	ADDQ AX, acc0
+	ADCQ DX, acc1
+	ADCQ $0, acc2
+	// Last reduction step
+	MOVQ acc3, AX
+	MOVQ acc3, t1
+	SHLQ $32, acc3
+	MULQ p256const1<>(SB)
+	SHRQ $32, t1
+	ADDQ acc3, acc4
+	ADCQ t1, acc5
+	ADCQ AX, acc0
+	ADCQ DX, acc1
+	ADCQ $0, acc2
+	// Copy result [255:0]
+	MOVQ acc4, x_ptr
+	MOVQ acc5, acc3
+	MOVQ acc0, t0
+	MOVQ acc1, t1
+	// Subtract p256
+	SUBQ $-1, acc4
+	SBBQ p256const0<>(SB) ,acc5
+	SBBQ $0, acc0
+	SBBQ p256const1<>(SB), acc1
+	SBBQ $0, acc2
+
+	CMOVQCS x_ptr, acc4
+	CMOVQCS acc3, acc5
+	CMOVQCS t0, acc0
+	CMOVQCS t1, acc1
+
+	MOVQ acc4, (8*0)(res_ptr)
+	MOVQ acc5, (8*1)(res_ptr)
+	MOVQ acc0, (8*2)(res_ptr)
+	MOVQ acc1, (8*3)(res_ptr)
+
+	RET
+/* ---------------------------------------*/
+// func p256FromMont(res, in *p256Element)
+TEXT ·p256FromMont(SB),NOSPLIT,$0
+	MOVQ res+0(FP), res_ptr
+	MOVQ in+8(FP), x_ptr
+
+	MOVQ (8*0)(x_ptr), acc0
+	MOVQ (8*1)(x_ptr), acc1
+	MOVQ (8*2)(x_ptr), acc2
+	MOVQ (8*3)(x_ptr), acc3
+	XORQ acc4, acc4
+
+	// Only reduce, no multiplications are needed
+	// First stage
+	MOVQ acc0, AX
+	MOVQ acc0, t1
+	SHLQ $32, acc0
+	MULQ p256const1<>(SB)
+	SHRQ $32, t1
+	ADDQ acc0, acc1
+	ADCQ t1, acc2
+	ADCQ AX, acc3
+	ADCQ DX, acc4
+	XORQ acc5, acc5
+	// Second stage
+	MOVQ acc1, AX
+	MOVQ acc1, t1
+	SHLQ $32, acc1
+	MULQ p256const1<>(SB)
+	SHRQ $32, t1
+	ADDQ acc1, acc2
+	ADCQ t1, acc3
+	ADCQ AX, acc4
+	ADCQ DX, acc5
+	XORQ acc0, acc0
+	// Third stage
+	MOVQ acc2, AX
+	MOVQ acc2, t1
+	SHLQ $32, acc2
+	MULQ p256const1<>(SB)
+	SHRQ $32, t1
+	ADDQ acc2, acc3
+	ADCQ t1, acc4
+	ADCQ AX, acc5
+	ADCQ DX, acc0
+	XORQ acc1, acc1
+	// Last stage
+	MOVQ acc3, AX
+	MOVQ acc3, t1
+	SHLQ $32, acc3
+	MULQ p256const1<>(SB)
+	SHRQ $32, t1
+	ADDQ acc3, acc4
+	ADCQ t1, acc5
+	ADCQ AX, acc0
+	ADCQ DX, acc1
+
+	MOVQ acc4, x_ptr
+	MOVQ acc5, acc3
+	MOVQ acc0, t0
+	MOVQ acc1, t1
+
+	SUBQ $-1, acc4
+	SBBQ p256const0<>(SB), acc5
+	SBBQ $0, acc0
+	SBBQ p256const1<>(SB), acc1
+
+	CMOVQCS x_ptr, acc4
+	CMOVQCS acc3, acc5
+	CMOVQCS t0, acc0
+	CMOVQCS t1, acc1
+
+	MOVQ acc4, (8*0)(res_ptr)
+	MOVQ acc5, (8*1)(res_ptr)
+	MOVQ acc0, (8*2)(res_ptr)
+	MOVQ acc1, (8*3)(res_ptr)
+
+	RET
+/* ---------------------------------------*/
+// func p256Select(res *P256Point, table *p256Table, idx int)
+TEXT ·p256Select(SB),NOSPLIT,$0
+	MOVQ idx+16(FP),AX
+	MOVQ table+8(FP),DI
+	MOVQ res+0(FP),DX
+
+	PXOR X15, X15	// X15 = 0
+	PCMPEQL X14, X14 // X14 = -1
+	PSUBL X14, X15   // X15 = 1
+	MOVL AX, X14
+	PSHUFD $0, X14, X14
+
+	PXOR X0, X0
+	PXOR X1, X1
+	PXOR X2, X2
+	PXOR X3, X3
+	PXOR X4, X4
+	PXOR X5, X5
+	MOVQ $16, AX
+
+	MOVOU X15, X13
+
+loop_select:
+
+		MOVOU X13, X12
+		PADDL X15, X13
+		PCMPEQL X14, X12
+
+		MOVOU (16*0)(DI), X6
+		MOVOU (16*1)(DI), X7
+		MOVOU (16*2)(DI), X8
+		MOVOU (16*3)(DI), X9
+		MOVOU (16*4)(DI), X10
+		MOVOU (16*5)(DI), X11
+		ADDQ $(16*6), DI
+
+		PAND X12, X6
+		PAND X12, X7
+		PAND X12, X8
+		PAND X12, X9
+		PAND X12, X10
+		PAND X12, X11
+
+		PXOR X6, X0
+		PXOR X7, X1
+		PXOR X8, X2
+		PXOR X9, X3
+		PXOR X10, X4
+		PXOR X11, X5
+
+		DECQ AX
+		JNE loop_select
+
+	MOVOU X0, (16*0)(DX)
+	MOVOU X1, (16*1)(DX)
+	MOVOU X2, (16*2)(DX)
+	MOVOU X3, (16*3)(DX)
+	MOVOU X4, (16*4)(DX)
+	MOVOU X5, (16*5)(DX)
+
+	RET
+/* ---------------------------------------*/
+// func p256SelectAffine(res *p256AffinePoint, table *p256AffineTable, idx int)
+TEXT ·p256SelectAffine(SB),NOSPLIT,$0
+	MOVQ idx+16(FP),AX
+	MOVQ table+8(FP),DI
+	MOVQ res+0(FP),DX
+
+	PXOR X15, X15	// X15 = 0
+	PCMPEQL X14, X14 // X14 = -1
+	PSUBL X14, X15   // X15 = 1
+	MOVL AX, X14
+	PSHUFD $0, X14, X14
+
+	PXOR X0, X0
+	PXOR X1, X1
+	PXOR X2, X2
+	PXOR X3, X3
+	MOVQ $16, AX
+
+	MOVOU X15, X13
+
+loop_select_base:
+
+		MOVOU X13, X12
+		PADDL X15, X13
+		PCMPEQL X14, X12
+
+		MOVOU (16*0)(DI), X4
+		MOVOU (16*1)(DI), X5
+		MOVOU (16*2)(DI), X6
+		MOVOU (16*3)(DI), X7
+
+		MOVOU (16*4)(DI), X8
+		MOVOU (16*5)(DI), X9
+		MOVOU (16*6)(DI), X10
+		MOVOU (16*7)(DI), X11
+
+		ADDQ $(16*8), DI
+
+		PAND X12, X4
+		PAND X12, X5
+		PAND X12, X6
+		PAND X12, X7
+
+		MOVOU X13, X12
+		PADDL X15, X13
+		PCMPEQL X14, X12
+
+		PAND X12, X8
+		PAND X12, X9
+		PAND X12, X10
+		PAND X12, X11
+
+		PXOR X4, X0
+		PXOR X5, X1
+		PXOR X6, X2
+		PXOR X7, X3
+
+		PXOR X8, X0
+		PXOR X9, X1
+		PXOR X10, X2
+		PXOR X11, X3
+
+		DECQ AX
+		JNE loop_select_base
+
+	MOVOU X0, (16*0)(DX)
+	MOVOU X1, (16*1)(DX)
+	MOVOU X2, (16*2)(DX)
+	MOVOU X3, (16*3)(DX)
+
+	RET
+/* ---------------------------------------*/
+// func p256OrdMul(res, in1, in2 *p256OrdElement)
+TEXT ·p256OrdMul(SB),NOSPLIT,$0
+	MOVQ res+0(FP), res_ptr
+	MOVQ in1+8(FP), x_ptr
+	MOVQ in2+16(FP), y_ptr
+	// x * y[0]
+	MOVQ (8*0)(y_ptr), t0
+
+	MOVQ (8*0)(x_ptr), AX
+	MULQ t0
+	MOVQ AX, acc0
+	MOVQ DX, acc1
+
+	MOVQ (8*1)(x_ptr), AX
+	MULQ t0
+	ADDQ AX, acc1
+	ADCQ $0, DX
+	MOVQ DX, acc2
+
+	MOVQ (8*2)(x_ptr), AX
+	MULQ t0
+	ADDQ AX, acc2
+	ADCQ $0, DX
+	MOVQ DX, acc3
+
+	MOVQ (8*3)(x_ptr), AX
+	MULQ t0
+	ADDQ AX, acc3
+	ADCQ $0, DX
+	MOVQ DX, acc4
+	XORQ acc5, acc5
+	// First reduction step
+	MOVQ acc0, AX
+	MULQ p256ordK0<>(SB)
+	MOVQ AX, t0
+
+	MOVQ p256ord<>+0x00(SB), AX
+	MULQ t0
+	ADDQ AX, acc0
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ p256ord<>+0x08(SB), AX
+	MULQ t0
+	ADDQ t1, acc1
+	ADCQ $0, DX
+	ADDQ AX, acc1
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ p256ord<>+0x10(SB), AX
+	MULQ t0
+	ADDQ t1, acc2
+	ADCQ $0, DX
+	ADDQ AX, acc2
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ p256ord<>+0x18(SB), AX
+	MULQ t0
+	ADDQ t1, acc3
+	ADCQ $0, DX
+	ADDQ AX, acc3
+	ADCQ DX, acc4
+	ADCQ $0, acc5
+	// x * y[1]
+	MOVQ (8*1)(y_ptr), t0
+
+	MOVQ (8*0)(x_ptr), AX
+	MULQ t0
+	ADDQ AX, acc1
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ (8*1)(x_ptr), AX
+	MULQ t0
+	ADDQ t1, acc2
+	ADCQ $0, DX
+	ADDQ AX, acc2
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ (8*2)(x_ptr), AX
+	MULQ t0
+	ADDQ t1, acc3
+	ADCQ $0, DX
+	ADDQ AX, acc3
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ (8*3)(x_ptr), AX
+	MULQ t0
+	ADDQ t1, acc4
+	ADCQ $0, DX
+	ADDQ AX, acc4
+	ADCQ DX, acc5
+	ADCQ $0, acc0
+	// Second reduction step
+	MOVQ acc1, AX
+	MULQ p256ordK0<>(SB)
+	MOVQ AX, t0
+
+	MOVQ p256ord<>+0x00(SB), AX
+	MULQ t0
+	ADDQ AX, acc1
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ p256ord<>+0x08(SB), AX
+	MULQ t0
+	ADDQ t1, acc2
+	ADCQ $0, DX
+	ADDQ AX, acc2
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ p256ord<>+0x10(SB), AX
+	MULQ t0
+	ADDQ t1, acc3
+	ADCQ $0, DX
+	ADDQ AX, acc3
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ p256ord<>+0x18(SB), AX
+	MULQ t0
+	ADDQ t1, acc4
+	ADCQ $0, DX
+	ADDQ AX, acc4
+	ADCQ DX, acc5
+	ADCQ $0, acc0
+	// x * y[2]
+	MOVQ (8*2)(y_ptr), t0
+
+	MOVQ (8*0)(x_ptr), AX
+	MULQ t0
+	ADDQ AX, acc2
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ (8*1)(x_ptr), AX
+	MULQ t0
+	ADDQ t1, acc3
+	ADCQ $0, DX
+	ADDQ AX, acc3
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ (8*2)(x_ptr), AX
+	MULQ t0
+	ADDQ t1, acc4
+	ADCQ $0, DX
+	ADDQ AX, acc4
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ (8*3)(x_ptr), AX
+	MULQ t0
+	ADDQ t1, acc5
+	ADCQ $0, DX
+	ADDQ AX, acc5
+	ADCQ DX, acc0
+	ADCQ $0, acc1
+	// Third reduction step
+	MOVQ acc2, AX
+	MULQ p256ordK0<>(SB)
+	MOVQ AX, t0
+
+	MOVQ p256ord<>+0x00(SB), AX
+	MULQ t0
+	ADDQ AX, acc2
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ p256ord<>+0x08(SB), AX
+	MULQ t0
+	ADDQ t1, acc3
+	ADCQ $0, DX
+	ADDQ AX, acc3
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ p256ord<>+0x10(SB), AX
+	MULQ t0
+	ADDQ t1, acc4
+	ADCQ $0, DX
+	ADDQ AX, acc4
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ p256ord<>+0x18(SB), AX
+	MULQ t0
+	ADDQ t1, acc5
+	ADCQ $0, DX
+	ADDQ AX, acc5
+	ADCQ DX, acc0
+	ADCQ $0, acc1
+	// x * y[3]
+	MOVQ (8*3)(y_ptr), t0
+
+	MOVQ (8*0)(x_ptr), AX
+	MULQ t0
+	ADDQ AX, acc3
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ (8*1)(x_ptr), AX
+	MULQ t0
+	ADDQ t1, acc4
+	ADCQ $0, DX
+	ADDQ AX, acc4
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ (8*2)(x_ptr), AX
+	MULQ t0
+	ADDQ t1, acc5
+	ADCQ $0, DX
+	ADDQ AX, acc5
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ (8*3)(x_ptr), AX
+	MULQ t0
+	ADDQ t1, acc0
+	ADCQ $0, DX
+	ADDQ AX, acc0
+	ADCQ DX, acc1
+	ADCQ $0, acc2
+	// Last reduction step
+	MOVQ acc3, AX
+	MULQ p256ordK0<>(SB)
+	MOVQ AX, t0
+
+	MOVQ p256ord<>+0x00(SB), AX
+	MULQ t0
+	ADDQ AX, acc3
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ p256ord<>+0x08(SB), AX
+	MULQ t0
+	ADDQ t1, acc4
+	ADCQ $0, DX
+	ADDQ AX, acc4
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ p256ord<>+0x10(SB), AX
+	MULQ t0
+	ADDQ t1, acc5
+	ADCQ $0, DX
+	ADDQ AX, acc5
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ p256ord<>+0x18(SB), AX
+	MULQ t0
+	ADDQ t1, acc0
+	ADCQ $0, DX
+	ADDQ AX, acc0
+	ADCQ DX, acc1
+	ADCQ $0, acc2
+	// Copy result [255:0]
+	MOVQ acc4, x_ptr
+	MOVQ acc5, acc3
+	MOVQ acc0, t0
+	MOVQ acc1, t1
+	// Subtract p256
+	SUBQ p256ord<>+0x00(SB), acc4
+	SBBQ p256ord<>+0x08(SB) ,acc5
+	SBBQ p256ord<>+0x10(SB), acc0
+	SBBQ p256ord<>+0x18(SB), acc1
+	SBBQ $0, acc2
+
+	CMOVQCS x_ptr, acc4
+	CMOVQCS acc3, acc5
+	CMOVQCS t0, acc0
+	CMOVQCS t1, acc1
+
+	MOVQ acc4, (8*0)(res_ptr)
+	MOVQ acc5, (8*1)(res_ptr)
+	MOVQ acc0, (8*2)(res_ptr)
+	MOVQ acc1, (8*3)(res_ptr)
+
+	RET
+/* ---------------------------------------*/
+// func p256OrdSqr(res, in *p256OrdElement, n int)
+TEXT ·p256OrdSqr(SB),NOSPLIT,$0
+	MOVQ res+0(FP), res_ptr
+	MOVQ in+8(FP), x_ptr
+	MOVQ n+16(FP), BX
+
+ordSqrLoop:
+
+	// y[1:] * y[0]
+	MOVQ (8*0)(x_ptr), t0
+
+	MOVQ (8*1)(x_ptr), AX
+	MULQ t0
+	MOVQ AX, acc1
+	MOVQ DX, acc2
+
+	MOVQ (8*2)(x_ptr), AX
+	MULQ t0
+	ADDQ AX, acc2
+	ADCQ $0, DX
+	MOVQ DX, acc3
+
+	MOVQ (8*3)(x_ptr), AX
+	MULQ t0
+	ADDQ AX, acc3
+	ADCQ $0, DX
+	MOVQ DX, acc4
+	// y[2:] * y[1]
+	MOVQ (8*1)(x_ptr), t0
+
+	MOVQ (8*2)(x_ptr), AX
+	MULQ t0
+	ADDQ AX, acc3
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ (8*3)(x_ptr), AX
+	MULQ t0
+	ADDQ t1, acc4
+	ADCQ $0, DX
+	ADDQ AX, acc4
+	ADCQ $0, DX
+	MOVQ DX, acc5
+	// y[3] * y[2]
+	MOVQ (8*2)(x_ptr), t0
+
+	MOVQ (8*3)(x_ptr), AX
+	MULQ t0
+	ADDQ AX, acc5
+	ADCQ $0, DX
+	MOVQ DX, y_ptr
+	XORQ t1, t1
+	// *2
+	ADDQ acc1, acc1
+	ADCQ acc2, acc2
+	ADCQ acc3, acc3
+	ADCQ acc4, acc4
+	ADCQ acc5, acc5
+	ADCQ y_ptr, y_ptr
+	ADCQ $0, t1
+	// Missing products
+	MOVQ (8*0)(x_ptr), AX
+	MULQ AX
+	MOVQ AX, acc0
+	MOVQ DX, t0
+
+	MOVQ (8*1)(x_ptr), AX
+	MULQ AX
+	ADDQ t0, acc1
+	ADCQ AX, acc2
+	ADCQ $0, DX
+	MOVQ DX, t0
+
+	MOVQ (8*2)(x_ptr), AX
+	MULQ AX
+	ADDQ t0, acc3
+	ADCQ AX, acc4
+	ADCQ $0, DX
+	MOVQ DX, t0
+
+	MOVQ (8*3)(x_ptr), AX
+	MULQ AX
+	ADDQ t0, acc5
+	ADCQ AX, y_ptr
+	ADCQ DX, t1
+	MOVQ t1, x_ptr
+	// First reduction step
+	MOVQ acc0, AX
+	MULQ p256ordK0<>(SB)
+	MOVQ AX, t0
+
+	MOVQ p256ord<>+0x00(SB), AX
+	MULQ t0
+	ADDQ AX, acc0
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ p256ord<>+0x08(SB), AX
+	MULQ t0
+	ADDQ t1, acc1
+	ADCQ $0, DX
+	ADDQ AX, acc1
+
+	MOVQ t0, t1
+	ADCQ DX, acc2
+	ADCQ $0, t1
+	SUBQ t0, acc2
+	SBBQ $0, t1
+
+	MOVQ t0, AX
+	MOVQ t0, DX
+	MOVQ t0, acc0
+	SHLQ $32, AX
+	SHRQ $32, DX
+
+	ADDQ t1, acc3
+	ADCQ $0, acc0
+	SUBQ AX, acc3
+	SBBQ DX, acc0
+	// Second reduction step
+	MOVQ acc1, AX
+	MULQ p256ordK0<>(SB)
+	MOVQ AX, t0
+
+	MOVQ p256ord<>+0x00(SB), AX
+	MULQ t0
+	ADDQ AX, acc1
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ p256ord<>+0x08(SB), AX
+	MULQ t0
+	ADDQ t1, acc2
+	ADCQ $0, DX
+	ADDQ AX, acc2
+
+	MOVQ t0, t1
+	ADCQ DX, acc3
+	ADCQ $0, t1
+	SUBQ t0, acc3
+	SBBQ $0, t1
+
+	MOVQ t0, AX
+	MOVQ t0, DX
+	MOVQ t0, acc1
+	SHLQ $32, AX
+	SHRQ $32, DX
+
+	ADDQ t1, acc0
+	ADCQ $0, acc1
+	SUBQ AX, acc0
+	SBBQ DX, acc1
+	// Third reduction step
+	MOVQ acc2, AX
+	MULQ p256ordK0<>(SB)
+	MOVQ AX, t0
+
+	MOVQ p256ord<>+0x00(SB), AX
+	MULQ t0
+	ADDQ AX, acc2
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ p256ord<>+0x08(SB), AX
+	MULQ t0
+	ADDQ t1, acc3
+	ADCQ $0, DX
+	ADDQ AX, acc3
+
+	MOVQ t0, t1
+	ADCQ DX, acc0
+	ADCQ $0, t1
+	SUBQ t0, acc0
+	SBBQ $0, t1
+
+	MOVQ t0, AX
+	MOVQ t0, DX
+	MOVQ t0, acc2
+	SHLQ $32, AX
+	SHRQ $32, DX
+
+	ADDQ t1, acc1
+	ADCQ $0, acc2
+	SUBQ AX, acc1
+	SBBQ DX, acc2
+	// Last reduction step
+	MOVQ acc3, AX
+	MULQ p256ordK0<>(SB)
+	MOVQ AX, t0
+
+	MOVQ p256ord<>+0x00(SB), AX
+	MULQ t0
+	ADDQ AX, acc3
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ p256ord<>+0x08(SB), AX
+	MULQ t0
+	ADDQ t1, acc0
+	ADCQ $0, DX
+	ADDQ AX, acc0
+	ADCQ $0, DX
+	MOVQ DX, t1
+
+	MOVQ t0, t1
+	ADCQ DX, acc1
+	ADCQ $0, t1
+	SUBQ t0, acc1
+	SBBQ $0, t1
+
+	MOVQ t0, AX
+	MOVQ t0, DX
+	MOVQ t0, acc3
+	SHLQ $32, AX
+	SHRQ $32, DX
+
+	ADDQ t1, acc2
+	ADCQ $0, acc3
+	SUBQ AX, acc2
+	SBBQ DX, acc3
+	XORQ t0, t0
+	// Add bits [511:256] of the sqr result
+	ADCQ acc4, acc0
+	ADCQ acc5, acc1
+	ADCQ y_ptr, acc2
+	ADCQ x_ptr, acc3
+	ADCQ $0, t0
+
+	MOVQ acc0, acc4
+	MOVQ acc1, acc5
+	MOVQ acc2, y_ptr
+	MOVQ acc3, t1
+	// Subtract p256
+	SUBQ p256ord<>+0x00(SB), acc0
+	SBBQ p256ord<>+0x08(SB) ,acc1
+	SBBQ p256ord<>+0x10(SB), acc2
+	SBBQ p256ord<>+0x18(SB), acc3
+	SBBQ $0, t0
+
+	CMOVQCS acc4, acc0
+	CMOVQCS acc5, acc1
+	CMOVQCS y_ptr, acc2
+	CMOVQCS t1, acc3
+
+	MOVQ acc0, (8*0)(res_ptr)
+	MOVQ acc1, (8*1)(res_ptr)
+	MOVQ acc2, (8*2)(res_ptr)
+	MOVQ acc3, (8*3)(res_ptr)
+	MOVQ res_ptr, x_ptr
+	DECQ BX
+	JNE ordSqrLoop
+
+	RET
+/* ---------------------------------------*/
+#undef res_ptr
+#undef x_ptr
+#undef y_ptr
+
+#undef acc0
+#undef acc1
+#undef acc2
+#undef acc3
+#undef acc4
+#undef acc5
+#undef t0
+#undef t1
+/* ---------------------------------------*/
+#define mul0 AX
+#define mul1 DX
+#define acc0 BX
+#define acc1 CX
+#define acc2 R8
+#define acc3 R9
+#define acc4 R10
+#define acc5 R11
+#define acc6 R12
+#define acc7 R13
+#define t0 R14
+#define t1 R15
+#define t2 DI
+#define t3 SI
+#define hlp BP
+/* ---------------------------------------*/
+TEXT p256SubInternal(SB),NOSPLIT,$0
+	XORQ mul0, mul0
+	SUBQ t0, acc4
+	SBBQ t1, acc5
+	SBBQ t2, acc6
+	SBBQ t3, acc7
+	SBBQ $0, mul0
+
+	MOVQ acc4, acc0
+	MOVQ acc5, acc1
+	MOVQ acc6, acc2
+	MOVQ acc7, acc3
+
+	ADDQ $-1, acc4
+	ADCQ p256const0<>(SB), acc5
+	ADCQ $0, acc6
+	ADCQ p256const1<>(SB), acc7
+	ANDQ $1, mul0
+
+	CMOVQEQ acc0, acc4
+	CMOVQEQ acc1, acc5
+	CMOVQEQ acc2, acc6
+	CMOVQEQ acc3, acc7
+
+	RET
+/* ---------------------------------------*/
+TEXT p256MulInternal(SB),NOSPLIT,$8
+	MOVQ acc4, mul0
+	MULQ t0
+	MOVQ mul0, acc0
+	MOVQ mul1, acc1
+
+	MOVQ acc4, mul0
+	MULQ t1
+	ADDQ mul0, acc1
+	ADCQ $0, mul1
+	MOVQ mul1, acc2
+
+	MOVQ acc4, mul0
+	MULQ t2
+	ADDQ mul0, acc2
+	ADCQ $0, mul1
+	MOVQ mul1, acc3
+
+	MOVQ acc4, mul0
+	MULQ t3
+	ADDQ mul0, acc3
+	ADCQ $0, mul1
+	MOVQ mul1, acc4
+
+	MOVQ acc5, mul0
+	MULQ t0
+	ADDQ mul0, acc1
+	ADCQ $0, mul1
+	MOVQ mul1, hlp
+
+	MOVQ acc5, mul0
+	MULQ t1
+	ADDQ hlp, acc2
+	ADCQ $0, mul1
+	ADDQ mul0, acc2
+	ADCQ $0, mul1
+	MOVQ mul1, hlp
+
+	MOVQ acc5, mul0
+	MULQ t2
+	ADDQ hlp, acc3
+	ADCQ $0, mul1
+	ADDQ mul0, acc3
+	ADCQ $0, mul1
+	MOVQ mul1, hlp
+
+	MOVQ acc5, mul0
+	MULQ t3
+	ADDQ hlp, acc4
+	ADCQ $0, mul1
+	ADDQ mul0, acc4
+	ADCQ $0, mul1
+	MOVQ mul1, acc5
+
+	MOVQ acc6, mul0
+	MULQ t0
+	ADDQ mul0, acc2
+	ADCQ $0, mul1
+	MOVQ mul1, hlp
+
+	MOVQ acc6, mul0
+	MULQ t1
+	ADDQ hlp, acc3
+	ADCQ $0, mul1
+	ADDQ mul0, acc3
+	ADCQ $0, mul1
+	MOVQ mul1, hlp
+
+	MOVQ acc6, mul0
+	MULQ t2
+	ADDQ hlp, acc4
+	ADCQ $0, mul1
+	ADDQ mul0, acc4
+	ADCQ $0, mul1
+	MOVQ mul1, hlp
+
+	MOVQ acc6, mul0
+	MULQ t3
+	ADDQ hlp, acc5
+	ADCQ $0, mul1
+	ADDQ mul0, acc5
+	ADCQ $0, mul1
+	MOVQ mul1, acc6
+
+	MOVQ acc7, mul0
+	MULQ t0
+	ADDQ mul0, acc3
+	ADCQ $0, mul1
+	MOVQ mul1, hlp
+
+	MOVQ acc7, mul0
+	MULQ t1
+	ADDQ hlp, acc4
+	ADCQ $0, mul1
+	ADDQ mul0, acc4
+	ADCQ $0, mul1
+	MOVQ mul1, hlp
+
+	MOVQ acc7, mul0
+	MULQ t2
+	ADDQ hlp, acc5
+	ADCQ $0, mul1
+	ADDQ mul0, acc5
+	ADCQ $0, mul1
+	MOVQ mul1, hlp
+
+	MOVQ acc7, mul0
+	MULQ t3
+	ADDQ hlp, acc6
+	ADCQ $0, mul1
+	ADDQ mul0, acc6
+	ADCQ $0, mul1
+	MOVQ mul1, acc7
+	// First reduction step
+	MOVQ acc0, mul0
+	MOVQ acc0, hlp
+	SHLQ $32, acc0
+	MULQ p256const1<>(SB)
+	SHRQ $32, hlp
+	ADDQ acc0, acc1
+	ADCQ hlp, acc2
+	ADCQ mul0, acc3
+	ADCQ $0, mul1
+	MOVQ mul1, acc0
+	// Second reduction step
+	MOVQ acc1, mul0
+	MOVQ acc1, hlp
+	SHLQ $32, acc1
+	MULQ p256const1<>(SB)
+	SHRQ $32, hlp
+	ADDQ acc1, acc2
+	ADCQ hlp, acc3
+	ADCQ mul0, acc0
+	ADCQ $0, mul1
+	MOVQ mul1, acc1
+	// Third reduction step
+	MOVQ acc2, mul0
+	MOVQ acc2, hlp
+	SHLQ $32, acc2
+	MULQ p256const1<>(SB)
+	SHRQ $32, hlp
+	ADDQ acc2, acc3
+	ADCQ hlp, acc0
+	ADCQ mul0, acc1
+	ADCQ $0, mul1
+	MOVQ mul1, acc2
+	// Last reduction step
+	MOVQ acc3, mul0
+	MOVQ acc3, hlp
+	SHLQ $32, acc3
+	MULQ p256const1<>(SB)
+	SHRQ $32, hlp
+	ADDQ acc3, acc0
+	ADCQ hlp, acc1
+	ADCQ mul0, acc2
+	ADCQ $0, mul1
+	MOVQ mul1, acc3
+	MOVQ $0, BP
+	// Add bits [511:256] of the result
+	ADCQ acc0, acc4
+	ADCQ acc1, acc5
+	ADCQ acc2, acc6
+	ADCQ acc3, acc7
+	ADCQ $0, hlp
+	// Copy result
+	MOVQ acc4, acc0
+	MOVQ acc5, acc1
+	MOVQ acc6, acc2
+	MOVQ acc7, acc3
+	// Subtract p256
+	SUBQ $-1, acc4
+	SBBQ p256const0<>(SB) ,acc5
+	SBBQ $0, acc6
+	SBBQ p256const1<>(SB), acc7
+	SBBQ $0, hlp
+	// If the result of the subtraction is negative, restore the previous result
+	CMOVQCS acc0, acc4
+	CMOVQCS acc1, acc5
+	CMOVQCS acc2, acc6
+	CMOVQCS acc3, acc7
+
+	RET
+/* ---------------------------------------*/
+TEXT p256SqrInternal(SB),NOSPLIT,$8
+
+	MOVQ acc4, mul0
+	MULQ acc5
+	MOVQ mul0, acc1
+	MOVQ mul1, acc2
+
+	MOVQ acc4, mul0
+	MULQ acc6
+	ADDQ mul0, acc2
+	ADCQ $0, mul1
+	MOVQ mul1, acc3
+
+	MOVQ acc4, mul0
+	MULQ acc7
+	ADDQ mul0, acc3
+	ADCQ $0, mul1
+	MOVQ mul1, t0
+
+	MOVQ acc5, mul0
+	MULQ acc6
+	ADDQ mul0, acc3
+	ADCQ $0, mul1
+	MOVQ mul1, hlp
+
+	MOVQ acc5, mul0
+	MULQ acc7
+	ADDQ hlp, t0
+	ADCQ $0, mul1
+	ADDQ mul0, t0
+	ADCQ $0, mul1
+	MOVQ mul1, t1
+
+	MOVQ acc6, mul0
+	MULQ acc7
+	ADDQ mul0, t1
+	ADCQ $0, mul1
+	MOVQ mul1, t2
+	XORQ t3, t3
+	// *2
+	ADDQ acc1, acc1
+	ADCQ acc2, acc2
+	ADCQ acc3, acc3
+	ADCQ t0, t0
+	ADCQ t1, t1
+	ADCQ t2, t2
+	ADCQ $0, t3
+	// Missing products
+	MOVQ acc4, mul0
+	MULQ mul0
+	MOVQ mul0, acc0
+	MOVQ DX, acc4
+
+	MOVQ acc5, mul0
+	MULQ mul0
+	ADDQ acc4, acc1
+	ADCQ mul0, acc2
+	ADCQ $0, DX
+	MOVQ DX, acc4
+
+	MOVQ acc6, mul0
+	MULQ mul0
+	ADDQ acc4, acc3
+	ADCQ mul0, t0
+	ADCQ $0, DX
+	MOVQ DX, acc4
+
+	MOVQ acc7, mul0
+	MULQ mul0
+	ADDQ acc4, t1
+	ADCQ mul0, t2
+	ADCQ DX, t3
+	// First reduction step
+	MOVQ acc0, mul0
+	MOVQ acc0, hlp
+	SHLQ $32, acc0
+	MULQ p256const1<>(SB)
+	SHRQ $32, hlp
+	ADDQ acc0, acc1
+	ADCQ hlp, acc2
+	ADCQ mul0, acc3
+	ADCQ $0, mul1
+	MOVQ mul1, acc0
+	// Second reduction step
+	MOVQ acc1, mul0
+	MOVQ acc1, hlp
+	SHLQ $32, acc1
+	MULQ p256const1<>(SB)
+	SHRQ $32, hlp
+	ADDQ acc1, acc2
+	ADCQ hlp, acc3
+	ADCQ mul0, acc0
+	ADCQ $0, mul1
+	MOVQ mul1, acc1
+	// Third reduction step
+	MOVQ acc2, mul0
+	MOVQ acc2, hlp
+	SHLQ $32, acc2
+	MULQ p256const1<>(SB)
+	SHRQ $32, hlp
+	ADDQ acc2, acc3
+	ADCQ hlp, acc0
+	ADCQ mul0, acc1
+	ADCQ $0, mul1
+	MOVQ mul1, acc2
+	// Last reduction step
+	MOVQ acc3, mul0
+	MOVQ acc3, hlp
+	SHLQ $32, acc3
+	MULQ p256const1<>(SB)
+	SHRQ $32, hlp
+	ADDQ acc3, acc0
+	ADCQ hlp, acc1
+	ADCQ mul0, acc2
+	ADCQ $0, mul1
+	MOVQ mul1, acc3
+	MOVQ $0, BP
+	// Add bits [511:256] of the result
+	ADCQ acc0, t0
+	ADCQ acc1, t1
+	ADCQ acc2, t2
+	ADCQ acc3, t3
+	ADCQ $0, hlp
+	// Copy result
+	MOVQ t0, acc4
+	MOVQ t1, acc5
+	MOVQ t2, acc6
+	MOVQ t3, acc7
+	// Subtract p256
+	SUBQ $-1, acc4
+	SBBQ p256const0<>(SB) ,acc5
+	SBBQ $0, acc6
+	SBBQ p256const1<>(SB), acc7
+	SBBQ $0, hlp
+	// If the result of the subtraction is negative, restore the previous result
+	CMOVQCS t0, acc4
+	CMOVQCS t1, acc5
+	CMOVQCS t2, acc6
+	CMOVQCS t3, acc7
+
+	RET
+/* ---------------------------------------*/
+#define p256MulBy2Inline\
+	XORQ mul0, mul0;\
+	ADDQ acc4, acc4;\
+	ADCQ acc5, acc5;\
+	ADCQ acc6, acc6;\
+	ADCQ acc7, acc7;\
+	ADCQ $0, mul0;\
+	MOVQ acc4, t0;\
+	MOVQ acc5, t1;\
+	MOVQ acc6, t2;\
+	MOVQ acc7, t3;\
+	SUBQ $-1, t0;\
+	SBBQ p256const0<>(SB), t1;\
+	SBBQ $0, t2;\
+	SBBQ p256const1<>(SB), t3;\
+	SBBQ $0, mul0;\
+	CMOVQCS acc4, t0;\
+	CMOVQCS acc5, t1;\
+	CMOVQCS acc6, t2;\
+	CMOVQCS acc7, t3;
+/* ---------------------------------------*/
+#define p256AddInline \
+	XORQ mul0, mul0;\
+	ADDQ t0, acc4;\
+	ADCQ t1, acc5;\
+	ADCQ t2, acc6;\
+	ADCQ t3, acc7;\
+	ADCQ $0, mul0;\
+	MOVQ acc4, t0;\
+	MOVQ acc5, t1;\
+	MOVQ acc6, t2;\
+	MOVQ acc7, t3;\
+	SUBQ $-1, t0;\
+	SBBQ p256const0<>(SB), t1;\
+	SBBQ $0, t2;\
+	SBBQ p256const1<>(SB), t3;\
+	SBBQ $0, mul0;\
+	CMOVQCS acc4, t0;\
+	CMOVQCS acc5, t1;\
+	CMOVQCS acc6, t2;\
+	CMOVQCS acc7, t3;
+/* ---------------------------------------*/
+#define LDacc(src) MOVQ src(8*0), acc4; MOVQ src(8*1), acc5; MOVQ src(8*2), acc6; MOVQ src(8*3), acc7
+#define LDt(src)   MOVQ src(8*0), t0; MOVQ src(8*1), t1; MOVQ src(8*2), t2; MOVQ src(8*3), t3
+#define ST(dst)    MOVQ acc4, dst(8*0); MOVQ acc5, dst(8*1); MOVQ acc6, dst(8*2); MOVQ acc7, dst(8*3)
+#define STt(dst)   MOVQ t0, dst(8*0); MOVQ t1, dst(8*1); MOVQ t2, dst(8*2); MOVQ t3, dst(8*3)
+#define acc2t      MOVQ acc4, t0; MOVQ acc5, t1; MOVQ acc6, t2; MOVQ acc7, t3
+#define t2acc      MOVQ t0, acc4; MOVQ t1, acc5; MOVQ t2, acc6; MOVQ t3, acc7
+/* ---------------------------------------*/
+#define x1in(off) (32*0 + off)(SP)
+#define y1in(off) (32*1 + off)(SP)
+#define z1in(off) (32*2 + off)(SP)
+#define x2in(off) (32*3 + off)(SP)
+#define y2in(off) (32*4 + off)(SP)
+#define xout(off) (32*5 + off)(SP)
+#define yout(off) (32*6 + off)(SP)
+#define zout(off) (32*7 + off)(SP)
+#define s2(off)   (32*8 + off)(SP)
+#define z1sqr(off) (32*9 + off)(SP)
+#define h(off)	  (32*10 + off)(SP)
+#define r(off)	  (32*11 + off)(SP)
+#define hsqr(off) (32*12 + off)(SP)
+#define rsqr(off) (32*13 + off)(SP)
+#define hcub(off) (32*14 + off)(SP)
+#define rptr	  (32*15)(SP)
+#define sel_save  (32*15 + 8)(SP)
+#define zero_save (32*15 + 8 + 4)(SP)
+
+// func p256PointAddAffineAsm(res, in1 *P256Point, in2 *p256AffinePoint, sign, sel, zero int)
+TEXT ·p256PointAddAffineAsm(SB),0,$512-48
+	// Move input to stack in order to free registers
+	MOVQ res+0(FP), AX
+	MOVQ in1+8(FP), BX
+	MOVQ in2+16(FP), CX
+	MOVQ sign+24(FP), DX
+	MOVQ sel+32(FP), t1
+	MOVQ zero+40(FP), t2
+
+	MOVOU (16*0)(BX), X0
+	MOVOU (16*1)(BX), X1
+	MOVOU (16*2)(BX), X2
+	MOVOU (16*3)(BX), X3
+	MOVOU (16*4)(BX), X4
+	MOVOU (16*5)(BX), X5
+
+	MOVOU X0, x1in(16*0)
+	MOVOU X1, x1in(16*1)
+	MOVOU X2, y1in(16*0)
+	MOVOU X3, y1in(16*1)
+	MOVOU X4, z1in(16*0)
+	MOVOU X5, z1in(16*1)
+
+	MOVOU (16*0)(CX), X0
+	MOVOU (16*1)(CX), X1
+
+	MOVOU X0, x2in(16*0)
+	MOVOU X1, x2in(16*1)
+	// Store pointer to result
+	MOVQ mul0, rptr
+	MOVL t1, sel_save
+	MOVL t2, zero_save
+	// Negate y2in based on sign
+	MOVQ (16*2 + 8*0)(CX), acc4
+	MOVQ (16*2 + 8*1)(CX), acc5
+	MOVQ (16*2 + 8*2)(CX), acc6
+	MOVQ (16*2 + 8*3)(CX), acc7
+	MOVQ $-1, acc0
+	MOVQ p256const0<>(SB), acc1
+	MOVQ $0, acc2
+	MOVQ p256const1<>(SB), acc3
+	XORQ mul0, mul0
+	// Speculatively subtract
+	SUBQ acc4, acc0
+	SBBQ acc5, acc1
+	SBBQ acc6, acc2
+	SBBQ acc7, acc3
+	SBBQ $0, mul0
+	MOVQ acc0, t0
+	MOVQ acc1, t1
+	MOVQ acc2, t2
+	MOVQ acc3, t3
+	// Add in case the operand was > p256
+	ADDQ $-1, acc0
+	ADCQ p256const0<>(SB), acc1
+	ADCQ $0, acc2
+	ADCQ p256const1<>(SB), acc3
+	ADCQ $0, mul0
+	CMOVQNE t0, acc0
+	CMOVQNE t1, acc1
+	CMOVQNE t2, acc2
+	CMOVQNE t3, acc3
+	// If condition is 0, keep original value
+	TESTQ DX, DX
+	CMOVQEQ acc4, acc0
+	CMOVQEQ acc5, acc1
+	CMOVQEQ acc6, acc2
+	CMOVQEQ acc7, acc3
+	// Store result
+	MOVQ acc0, y2in(8*0)
+	MOVQ acc1, y2in(8*1)
+	MOVQ acc2, y2in(8*2)
+	MOVQ acc3, y2in(8*3)
+	// Begin point add
+	LDacc (z1in)
+	CALL p256SqrInternal(SB)	// z1ˆ2
+	ST (z1sqr)
+
+	LDt (x2in)
+	CALL p256MulInternal(SB)	// x2 * z1ˆ2
+
+	LDt (x1in)
+	CALL p256SubInternal(SB)	// h = u2 - u1
+	ST (h)
+
+	LDt (z1in)
+	CALL p256MulInternal(SB)	// z3 = h * z1
+	ST (zout)
+
+	LDacc (z1sqr)
+	CALL p256MulInternal(SB)	// z1ˆ3
+
+	LDt (y2in)
+	CALL p256MulInternal(SB)	// s2 = y2 * z1ˆ3
+	ST (s2)
+
+	LDt (y1in)
+	CALL p256SubInternal(SB)	// r = s2 - s1
+	ST (r)
+
+	CALL p256SqrInternal(SB)	// rsqr = rˆ2
+	ST (rsqr)
+
+	LDacc (h)
+	CALL p256SqrInternal(SB)	// hsqr = hˆ2
+	ST (hsqr)
+
+	LDt (h)
+	CALL p256MulInternal(SB)	// hcub = hˆ3
+	ST (hcub)
+
+	LDt (y1in)
+	CALL p256MulInternal(SB)	// y1 * hˆ3
+	ST (s2)
+
+	LDacc (x1in)
+	LDt (hsqr)
+	CALL p256MulInternal(SB)	// u1 * hˆ2
+	ST (h)
+
+	p256MulBy2Inline			// u1 * hˆ2 * 2, inline
+	LDacc (rsqr)
+	CALL p256SubInternal(SB)	// rˆ2 - u1 * hˆ2 * 2
+
+	LDt (hcub)
+	CALL p256SubInternal(SB)
+	ST (xout)
+
+	MOVQ acc4, t0
+	MOVQ acc5, t1
+	MOVQ acc6, t2
+	MOVQ acc7, t3
+	LDacc (h)
+	CALL p256SubInternal(SB)
+
+	LDt (r)
+	CALL p256MulInternal(SB)
+
+	LDt (s2)
+	CALL p256SubInternal(SB)
+	ST (yout)
+	// Load stored values from stack
+	MOVQ rptr, AX
+	MOVL sel_save, BX
+	MOVL zero_save, CX
+	// The result is not valid if (sel == 0), conditional choose
+	MOVOU xout(16*0), X0
+	MOVOU xout(16*1), X1
+	MOVOU yout(16*0), X2
+	MOVOU yout(16*1), X3
+	MOVOU zout(16*0), X4
+	MOVOU zout(16*1), X5
+
+	MOVL BX, X6
+	MOVL CX, X7
+
+	PXOR X8, X8
+	PCMPEQL X9, X9
+
+	PSHUFD $0, X6, X6
+	PSHUFD $0, X7, X7
+
+	PCMPEQL X8, X6
+	PCMPEQL X8, X7
+
+	MOVOU X6, X15
+	PANDN X9, X15
+
+	MOVOU x1in(16*0), X9
+	MOVOU x1in(16*1), X10
+	MOVOU y1in(16*0), X11
+	MOVOU y1in(16*1), X12
+	MOVOU z1in(16*0), X13
+	MOVOU z1in(16*1), X14
+
+	PAND X15, X0
+	PAND X15, X1
+	PAND X15, X2
+	PAND X15, X3
+	PAND X15, X4
+	PAND X15, X5
+
+	PAND X6, X9
+	PAND X6, X10
+	PAND X6, X11
+	PAND X6, X12
+	PAND X6, X13
+	PAND X6, X14
+
+	PXOR X9, X0
+	PXOR X10, X1
+	PXOR X11, X2
+	PXOR X12, X3
+	PXOR X13, X4
+	PXOR X14, X5
+	// Similarly if zero == 0
+	PCMPEQL X9, X9
+	MOVOU X7, X15
+	PANDN X9, X15
+
+	MOVOU x2in(16*0), X9
+	MOVOU x2in(16*1), X10
+	MOVOU y2in(16*0), X11
+	MOVOU y2in(16*1), X12
+	MOVOU p256one<>+0x00(SB), X13
+	MOVOU p256one<>+0x10(SB), X14
+
+	PAND X15, X0
+	PAND X15, X1
+	PAND X15, X2
+	PAND X15, X3
+	PAND X15, X4
+	PAND X15, X5
+
+	PAND X7, X9
+	PAND X7, X10
+	PAND X7, X11
+	PAND X7, X12
+	PAND X7, X13
+	PAND X7, X14
+
+	PXOR X9, X0
+	PXOR X10, X1
+	PXOR X11, X2
+	PXOR X12, X3
+	PXOR X13, X4
+	PXOR X14, X5
+	// Finally output the result
+	MOVOU X0, (16*0)(AX)
+	MOVOU X1, (16*1)(AX)
+	MOVOU X2, (16*2)(AX)
+	MOVOU X3, (16*3)(AX)
+	MOVOU X4, (16*4)(AX)
+	MOVOU X5, (16*5)(AX)
+	MOVQ $0, rptr
+
+	RET
+#undef x1in
+#undef y1in
+#undef z1in
+#undef x2in
+#undef y2in
+#undef xout
+#undef yout
+#undef zout
+#undef s2
+#undef z1sqr
+#undef h
+#undef r
+#undef hsqr
+#undef rsqr
+#undef hcub
+#undef rptr
+#undef sel_save
+#undef zero_save
+
+// p256IsZero returns 1 in AX if [acc4..acc7] represents zero and zero
+// otherwise. It writes to [acc4..acc7], t0 and t1.
+TEXT p256IsZero(SB),NOSPLIT,$0
+	// AX contains a flag that is set if the input is zero.
+	XORQ AX, AX
+	MOVQ $1, t1
+
+	// Check whether [acc4..acc7] are all zero.
+	MOVQ acc4, t0
+	ORQ acc5, t0
+	ORQ acc6, t0
+	ORQ acc7, t0
+
+	// Set the zero flag if so. (CMOV of a constant to a register doesn't
+	// appear to be supported in Go. Thus t1 = 1.)
+	CMOVQEQ t1, AX
+
+	// XOR [acc4..acc7] with P and compare with zero again.
+	XORQ $-1, acc4
+	XORQ p256const0<>(SB), acc5
+	XORQ p256const1<>(SB), acc7
+	ORQ acc5, acc4
+	ORQ acc6, acc4
+	ORQ acc7, acc4
+
+	// Set the zero flag if so.
+	CMOVQEQ t1, AX
+	RET
+
+/* ---------------------------------------*/
+#define x1in(off) (32*0 + off)(SP)
+#define y1in(off) (32*1 + off)(SP)
+#define z1in(off) (32*2 + off)(SP)
+#define x2in(off) (32*3 + off)(SP)
+#define y2in(off) (32*4 + off)(SP)
+#define z2in(off) (32*5 + off)(SP)
+
+#define xout(off) (32*6 + off)(SP)
+#define yout(off) (32*7 + off)(SP)
+#define zout(off) (32*8 + off)(SP)
+
+#define u1(off)    (32*9 + off)(SP)
+#define u2(off)    (32*10 + off)(SP)
+#define s1(off)    (32*11 + off)(SP)
+#define s2(off)    (32*12 + off)(SP)
+#define z1sqr(off) (32*13 + off)(SP)
+#define z2sqr(off) (32*14 + off)(SP)
+#define h(off)     (32*15 + off)(SP)
+#define r(off)     (32*16 + off)(SP)
+#define hsqr(off)  (32*17 + off)(SP)
+#define rsqr(off)  (32*18 + off)(SP)
+#define hcub(off)  (32*19 + off)(SP)
+#define rptr       (32*20)(SP)
+#define points_eq  (32*20+8)(SP)
+
+//func p256PointAddAsm(res, in1, in2 *P256Point) int
+TEXT ·p256PointAddAsm(SB),0,$680-32
+	// See https://hyperelliptic.org/EFD/g1p/auto-shortw-jacobian-3.html#addition-add-2007-bl
+	// Move input to stack in order to free registers
+	MOVQ res+0(FP), AX
+	MOVQ in1+8(FP), BX
+	MOVQ in2+16(FP), CX
+
+	MOVOU (16*0)(BX), X0
+	MOVOU (16*1)(BX), X1
+	MOVOU (16*2)(BX), X2
+	MOVOU (16*3)(BX), X3
+	MOVOU (16*4)(BX), X4
+	MOVOU (16*5)(BX), X5
+
+	MOVOU X0, x1in(16*0)
+	MOVOU X1, x1in(16*1)
+	MOVOU X2, y1in(16*0)
+	MOVOU X3, y1in(16*1)
+	MOVOU X4, z1in(16*0)
+	MOVOU X5, z1in(16*1)
+
+	MOVOU (16*0)(CX), X0
+	MOVOU (16*1)(CX), X1
+	MOVOU (16*2)(CX), X2
+	MOVOU (16*3)(CX), X3
+	MOVOU (16*4)(CX), X4
+	MOVOU (16*5)(CX), X5
+
+	MOVOU X0, x2in(16*0)
+	MOVOU X1, x2in(16*1)
+	MOVOU X2, y2in(16*0)
+	MOVOU X3, y2in(16*1)
+	MOVOU X4, z2in(16*0)
+	MOVOU X5, z2in(16*1)
+	// Store pointer to result
+	MOVQ AX, rptr
+	// Begin point add
+	LDacc (z2in)
+	CALL p256SqrInternal(SB)	// z2ˆ2
+	ST (z2sqr)
+	LDt (z2in)
+	CALL p256MulInternal(SB)	// z2ˆ3
+	LDt (y1in)
+	CALL p256MulInternal(SB)	// s1 = z2ˆ3*y1
+	ST (s1)
+
+	LDacc (z1in)
+	CALL p256SqrInternal(SB)	// z1ˆ2
+	ST (z1sqr)
+	LDt (z1in)
+	CALL p256MulInternal(SB)	// z1ˆ3
+	LDt (y2in)
+	CALL p256MulInternal(SB)	// s2 = z1ˆ3*y2
+	ST (s2)
+
+	LDt (s1)
+	CALL p256SubInternal(SB)	// r = s2 - s1
+	ST (r)
+	CALL p256IsZero(SB)
+	MOVQ AX, points_eq
+
+	LDacc (z2sqr)
+	LDt (x1in)
+	CALL p256MulInternal(SB)	// u1 = x1 * z2ˆ2
+	ST (u1)
+	LDacc (z1sqr)
+	LDt (x2in)
+	CALL p256MulInternal(SB)	// u2 = x2 * z1ˆ2
+	ST (u2)
+
+	LDt (u1)
+	CALL p256SubInternal(SB)	// h = u2 - u1
+	ST (h)
+	CALL p256IsZero(SB)
+	ANDQ points_eq, AX
+	MOVQ AX, points_eq
+
+	LDacc (r)
+	CALL p256SqrInternal(SB)	// rsqr = rˆ2
+	ST (rsqr)
+
+	LDacc (h)
+	CALL p256SqrInternal(SB)	// hsqr = hˆ2
+	ST (hsqr)
+
+	LDt (h)
+	CALL p256MulInternal(SB)	// hcub = hˆ3
+	ST (hcub)
+
+	LDt (s1)
+	CALL p256MulInternal(SB)
+	ST (s2)
+
+	LDacc (z1in)
+	LDt (z2in)
+	CALL p256MulInternal(SB)	// z1 * z2
+	LDt (h)
+	CALL p256MulInternal(SB)	// z1 * z2 * h
+	ST (zout)
+
+	LDacc (hsqr)
+	LDt (u1)
+	CALL p256MulInternal(SB)	// hˆ2 * u1
+	ST (u2)
+
+	p256MulBy2Inline	// u1 * hˆ2 * 2, inline
+	LDacc (rsqr)
+	CALL p256SubInternal(SB)	// rˆ2 - u1 * hˆ2 * 2
+
+	LDt (hcub)
+	CALL p256SubInternal(SB)
+	ST (xout)
+
+	MOVQ acc4, t0
+	MOVQ acc5, t1
+	MOVQ acc6, t2
+	MOVQ acc7, t3
+	LDacc (u2)
+	CALL p256SubInternal(SB)
+
+	LDt (r)
+	CALL p256MulInternal(SB)
+
+	LDt (s2)
+	CALL p256SubInternal(SB)
+	ST (yout)
+
+	MOVOU xout(16*0), X0
+	MOVOU xout(16*1), X1
+	MOVOU yout(16*0), X2
+	MOVOU yout(16*1), X3
+	MOVOU zout(16*0), X4
+	MOVOU zout(16*1), X5
+	// Finally output the result
+	MOVQ rptr, AX
+	MOVQ $0, rptr
+	MOVOU X0, (16*0)(AX)
+	MOVOU X1, (16*1)(AX)
+	MOVOU X2, (16*2)(AX)
+	MOVOU X3, (16*3)(AX)
+	MOVOU X4, (16*4)(AX)
+	MOVOU X5, (16*5)(AX)
+
+	MOVQ points_eq, AX
+	MOVQ AX, ret+24(FP)
+
+	RET
+#undef x1in
+#undef y1in
+#undef z1in
+#undef x2in
+#undef y2in
+#undef z2in
+#undef xout
+#undef yout
+#undef zout
+#undef s1
+#undef s2
+#undef u1
+#undef u2
+#undef z1sqr
+#undef z2sqr
+#undef h
+#undef r
+#undef hsqr
+#undef rsqr
+#undef hcub
+#undef rptr
+/* ---------------------------------------*/
+#define x(off) (32*0 + off)(SP)
+#define y(off) (32*1 + off)(SP)
+#define z(off) (32*2 + off)(SP)
+
+#define s(off)	(32*3 + off)(SP)
+#define m(off)	(32*4 + off)(SP)
+#define zsqr(off) (32*5 + off)(SP)
+#define tmp(off)  (32*6 + off)(SP)
+#define rptr	  (32*7)(SP)
+
+//func p256PointDoubleAsm(res, in *P256Point)
+TEXT ·p256PointDoubleAsm(SB),NOSPLIT,$256-16
+	// Move input to stack in order to free registers
+	MOVQ res+0(FP), AX
+	MOVQ in+8(FP), BX
+
+	MOVOU (16*0)(BX), X0
+	MOVOU (16*1)(BX), X1
+	MOVOU (16*2)(BX), X2
+	MOVOU (16*3)(BX), X3
+	MOVOU (16*4)(BX), X4
+	MOVOU (16*5)(BX), X5
+
+	MOVOU X0, x(16*0)
+	MOVOU X1, x(16*1)
+	MOVOU X2, y(16*0)
+	MOVOU X3, y(16*1)
+	MOVOU X4, z(16*0)
+	MOVOU X5, z(16*1)
+	// Store pointer to result
+	MOVQ AX, rptr
+	// Begin point double
+	LDacc (z)
+	CALL p256SqrInternal(SB)
+	ST (zsqr)
+
+	LDt (x)
+	p256AddInline
+	STt (m)
+
+	LDacc (z)
+	LDt (y)
+	CALL p256MulInternal(SB)
+	p256MulBy2Inline
+	MOVQ rptr, AX
+	// Store z
+	MOVQ t0, (16*4 + 8*0)(AX)
+	MOVQ t1, (16*4 + 8*1)(AX)
+	MOVQ t2, (16*4 + 8*2)(AX)
+	MOVQ t3, (16*4 + 8*3)(AX)
+
+	LDacc (x)
+	LDt (zsqr)
+	CALL p256SubInternal(SB)
+	LDt (m)
+	CALL p256MulInternal(SB)
+	ST (m)
+	// Multiply by 3
+	p256MulBy2Inline
+	LDacc (m)
+	p256AddInline
+	STt (m)
+	////////////////////////
+	LDacc (y)
+	p256MulBy2Inline
+	t2acc
+	CALL p256SqrInternal(SB)
+	ST (s)
+	CALL p256SqrInternal(SB)
+	// Divide by 2
+	XORQ mul0, mul0
+	MOVQ acc4, t0
+	MOVQ acc5, t1
+	MOVQ acc6, t2
+	MOVQ acc7, t3
+
+	ADDQ $-1, acc4
+	ADCQ p256const0<>(SB), acc5
+	ADCQ $0, acc6
+	ADCQ p256const1<>(SB), acc7
+	ADCQ $0, mul0
+	TESTQ $1, t0
+
+	CMOVQEQ t0, acc4
+	CMOVQEQ t1, acc5
+	CMOVQEQ t2, acc6
+	CMOVQEQ t3, acc7
+	ANDQ t0, mul0
+
+	SHRQ $1, acc5, acc4
+	SHRQ $1, acc6, acc5
+	SHRQ $1, acc7, acc6
+	SHRQ $1, mul0, acc7
+	ST (y)
+	/////////////////////////
+	LDacc (x)
+	LDt (s)
+	CALL p256MulInternal(SB)
+	ST (s)
+	p256MulBy2Inline
+	STt (tmp)
+
+	LDacc (m)
+	CALL p256SqrInternal(SB)
+	LDt (tmp)
+	CALL p256SubInternal(SB)
+
+	MOVQ rptr, AX
+	// Store x
+	MOVQ acc4, (16*0 + 8*0)(AX)
+	MOVQ acc5, (16*0 + 8*1)(AX)
+	MOVQ acc6, (16*0 + 8*2)(AX)
+	MOVQ acc7, (16*0 + 8*3)(AX)
+
+	acc2t
+	LDacc (s)
+	CALL p256SubInternal(SB)
+
+	LDt (m)
+	CALL p256MulInternal(SB)
+
+	LDt (y)
+	CALL p256SubInternal(SB)
+	MOVQ rptr, AX
+	// Store y
+	MOVQ acc4, (16*2 + 8*0)(AX)
+	MOVQ acc5, (16*2 + 8*1)(AX)
+	MOVQ acc6, (16*2 + 8*2)(AX)
+	MOVQ acc7, (16*2 + 8*3)(AX)
+	///////////////////////
+	MOVQ $0, rptr
+
+	RET
+/* ---------------------------------------*/
diff --git a/contrib/go/_std_1.19/src/crypto/internal/nistec/p256_asm_ordinv.go b/contrib/go/_std_1.19/src/crypto/internal/nistec/p256_asm_ordinv.go
new file mode 100644
index 0000000000..86a7a230bd
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/internal/nistec/p256_asm_ordinv.go
@@ -0,0 +1,101 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build amd64 || arm64
+
+package nistec
+
+import "errors"
+
+// Montgomery multiplication modulo org(G). Sets res = in1 * in2 * R⁻¹.
+//
+//go:noescape
+func p256OrdMul(res, in1, in2 *p256OrdElement)
+
+// Montgomery square modulo org(G), repeated n times (n >= 1).
+//
+//go:noescape
+func p256OrdSqr(res, in *p256OrdElement, n int)
+
+func P256OrdInverse(k []byte) ([]byte, error) {
+	if len(k) != 32 {
+		return nil, errors.New("invalid scalar length")
+	}
+
+	x := new(p256OrdElement)
+	p256OrdBigToLittle(x, (*[32]byte)(k))
+
+	// Inversion is implemented as exponentiation by n - 2, per Fermat's little theorem.
+	//
+	// The sequence of 38 multiplications and 254 squarings is derived from
+	// https://briansmith.org/ecc-inversion-addition-chains-01#p256_scalar_inversion
+	_1 := new(p256OrdElement)
+	_11 := new(p256OrdElement)
+	_101 := new(p256OrdElement)
+	_111 := new(p256OrdElement)
+	_1111 := new(p256OrdElement)
+	_10101 := new(p256OrdElement)
+	_101111 := new(p256OrdElement)
+	t := new(p256OrdElement)
+
+	// This code operates in the Montgomery domain where R = 2²⁵⁶ mod n and n is
+	// the order of the scalar field. Elements in the Montgomery domain take the
+	// form a×R and p256OrdMul calculates (a × b × R⁻¹) mod n. RR is R in the
+	// domain, or R×R mod n, thus p256OrdMul(x, RR) gives x×R, i.e. converts x
+	// into the Montgomery domain.
+	RR := &p256OrdElement{0x83244c95be79eea2, 0x4699799c49bd6fa6,
+		0x2845b2392b6bec59, 0x66e12d94f3d95620}
+
+	p256OrdMul(_1, x, RR)      // _1
+	p256OrdSqr(x, _1, 1)       // _10
+	p256OrdMul(_11, x, _1)     // _11
+	p256OrdMul(_101, x, _11)   // _101
+	p256OrdMul(_111, x, _101)  // _111
+	p256OrdSqr(x, _101, 1)     // _1010
+	p256OrdMul(_1111, _101, x) // _1111
+
+	p256OrdSqr(t, x, 1)          // _10100
+	p256OrdMul(_10101, t, _1)    // _10101
+	p256OrdSqr(x, _10101, 1)     // _101010
+	p256OrdMul(_101111, _101, x) // _101111
+	p256OrdMul(x, _10101, x)     // _111111 = x6
+	p256OrdSqr(t, x, 2)          // _11111100
+	p256OrdMul(t, t, _11)        // _11111111 = x8
+	p256OrdSqr(x, t, 8)          // _ff00
+	p256OrdMul(x, x, t)          // _ffff = x16
+	p256OrdSqr(t, x, 16)         // _ffff0000
+	p256OrdMul(t, t, x)          // _ffffffff = x32
+
+	p256OrdSqr(x, t, 64)
+	p256OrdMul(x, x, t)
+	p256OrdSqr(x, x, 32)
+	p256OrdMul(x, x, t)
+
+	sqrs := []int{
+		6, 5, 4, 5, 5,
+		4, 3, 3, 5, 9,
+		6, 2, 5, 6, 5,
+		4, 5, 5, 3, 10,
+		2, 5, 5, 3, 7, 6}
+	muls := []*p256OrdElement{
+		_101111, _111, _11, _1111, _10101,
+		_101, _101, _101, _111, _101111,
+		_1111, _1, _1, _1111, _111,
+		_111, _111, _101, _11, _101111,
+		_11, _11, _11, _1, _10101, _1111}
+
+	for i, s := range sqrs {
+		p256OrdSqr(x, x, s)
+		p256OrdMul(x, x, muls[i])
+	}
+
+	// Montgomery multiplication by R⁻¹, or 1 outside the domain as R⁻¹×R = 1,
+	// converts a Montgomery value out of the domain.
+	one := &p256OrdElement{1}
+	p256OrdMul(x, x, one)
+
+	var xOut [32]byte
+	p256OrdLittleToBig(&xOut, x)
+	return xOut[:], nil
+}
diff --git a/contrib/go/_std_1.18/src/crypto/elliptic/p256_asm_table.bin b/contrib/go/_std_1.19/src/crypto/internal/nistec/p256_asm_table.bin
index 20c527e4e0..20c527e4e0 100644
--- a/contrib/go/_std_1.18/src/crypto/elliptic/p256_asm_table.bin
+++ b/contrib/go/_std_1.19/src/crypto/internal/nistec/p256_asm_table.bin
diff --git a/contrib/go/_std_1.19/src/crypto/internal/nistec/p384.go b/contrib/go/_std_1.19/src/crypto/internal/nistec/p384.go
new file mode 100644
index 0000000000..1a855cb713
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/internal/nistec/p384.go
@@ -0,0 +1,515 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Code generated by generate.go. DO NOT EDIT.
+
+package nistec
+
+import (
+	"crypto/internal/nistec/fiat"
+	"crypto/subtle"
+	"errors"
+	"sync"
+)
+
+var p384B, _ = new(fiat.P384Element).SetBytes([]byte{0xb3, 0x31, 0x2f, 0xa7, 0xe2, 0x3e, 0xe7, 0xe4, 0x98, 0x8e, 0x5, 0x6b, 0xe3, 0xf8, 0x2d, 0x19, 0x18, 0x1d, 0x9c, 0x6e, 0xfe, 0x81, 0x41, 0x12, 0x3, 0x14, 0x8, 0x8f, 0x50, 0x13, 0x87, 0x5a, 0xc6, 0x56, 0x39, 0x8d, 0x8a, 0x2e, 0xd1, 0x9d, 0x2a, 0x85, 0xc8, 0xed, 0xd3, 0xec, 0x2a, 0xef})
+
+var p384G, _ = NewP384Point().SetBytes([]byte{0x4, 0xaa, 0x87, 0xca, 0x22, 0xbe, 0x8b, 0x5, 0x37, 0x8e, 0xb1, 0xc7, 0x1e, 0xf3, 0x20, 0xad, 0x74, 0x6e, 0x1d, 0x3b, 0x62, 0x8b, 0xa7, 0x9b, 0x98, 0x59, 0xf7, 0x41, 0xe0, 0x82, 0x54, 0x2a, 0x38, 0x55, 0x2, 0xf2, 0x5d, 0xbf, 0x55, 0x29, 0x6c, 0x3a, 0x54, 0x5e, 0x38, 0x72, 0x76, 0xa, 0xb7, 0x36, 0x17, 0xde, 0x4a, 0x96, 0x26, 0x2c, 0x6f, 0x5d, 0x9e, 0x98, 0xbf, 0x92, 0x92, 0xdc, 0x29, 0xf8, 0xf4, 0x1d, 0xbd, 0x28, 0x9a, 0x14, 0x7c, 0xe9, 0xda, 0x31, 0x13, 0xb5, 0xf0, 0xb8, 0xc0, 0xa, 0x60, 0xb1, 0xce, 0x1d, 0x7e, 0x81, 0x9d, 0x7a, 0x43, 0x1d, 0x7c, 0x90, 0xea, 0xe, 0x5f})
+
+// p384ElementLength is the length of an element of the base or scalar field,
+// which have the same bytes length for all NIST P curves.
+const p384ElementLength = 48
+
+// P384Point is a P384 point. The zero value is NOT valid.
+type P384Point struct {
+	// The point is represented in projective coordinates (X:Y:Z),
+	// where x = X/Z and y = Y/Z.
+	x, y, z *fiat.P384Element
+}
+
+// NewP384Point returns a new P384Point representing the point at infinity point.
+func NewP384Point() *P384Point {
+	return &P384Point{
+		x: new(fiat.P384Element),
+		y: new(fiat.P384Element).One(),
+		z: new(fiat.P384Element),
+	}
+}
+
+// NewP384Generator returns a new P384Point set to the canonical generator.
+func NewP384Generator() *P384Point {
+	return (&P384Point{
+		x: new(fiat.P384Element),
+		y: new(fiat.P384Element),
+		z: new(fiat.P384Element),
+	}).Set(p384G)
+}
+
+// Set sets p = q and returns p.
+func (p *P384Point) Set(q *P384Point) *P384Point {
+	p.x.Set(q.x)
+	p.y.Set(q.y)
+	p.z.Set(q.z)
+	return p
+}
+
+// SetBytes sets p to the compressed, uncompressed, or infinity value encoded in
+// b, as specified in SEC 1, Version 2.0, Section 2.3.4. If the point is not on
+// the curve, it returns nil and an error, and the receiver is unchanged.
+// Otherwise, it returns p.
+func (p *P384Point) SetBytes(b []byte) (*P384Point, error) {
+	switch {
+	// Point at infinity.
+	case len(b) == 1 && b[0] == 0:
+		return p.Set(NewP384Point()), nil
+
+	// Uncompressed form.
+	case len(b) == 1+2*p384ElementLength && b[0] == 4:
+		x, err := new(fiat.P384Element).SetBytes(b[1 : 1+p384ElementLength])
+		if err != nil {
+			return nil, err
+		}
+		y, err := new(fiat.P384Element).SetBytes(b[1+p384ElementLength:])
+		if err != nil {
+			return nil, err
+		}
+		if err := p384CheckOnCurve(x, y); err != nil {
+			return nil, err
+		}
+		p.x.Set(x)
+		p.y.Set(y)
+		p.z.One()
+		return p, nil
+
+	// Compressed form.
+	case len(b) == 1+p384ElementLength && (b[0] == 2 || b[0] == 3):
+		x, err := new(fiat.P384Element).SetBytes(b[1:])
+		if err != nil {
+			return nil, err
+		}
+
+		// y² = x³ - 3x + b
+		y := p384Polynomial(new(fiat.P384Element), x)
+		if !p384Sqrt(y, y) {
+			return nil, errors.New("invalid P384 compressed point encoding")
+		}
+
+		// Select the positive or negative root, as indicated by the least
+		// significant bit, based on the encoding type byte.
+		otherRoot := new(fiat.P384Element)
+		otherRoot.Sub(otherRoot, y)
+		cond := y.Bytes()[p384ElementLength-1]&1 ^ b[0]&1
+		y.Select(otherRoot, y, int(cond))
+
+		p.x.Set(x)
+		p.y.Set(y)
+		p.z.One()
+		return p, nil
+
+	default:
+		return nil, errors.New("invalid P384 point encoding")
+	}
+}
+
+// p384Polynomial sets y2 to x³ - 3x + b, and returns y2.
+func p384Polynomial(y2, x *fiat.P384Element) *fiat.P384Element {
+	y2.Square(x)
+	y2.Mul(y2, x)
+
+	threeX := new(fiat.P384Element).Add(x, x)
+	threeX.Add(threeX, x)
+
+	y2.Sub(y2, threeX)
+	return y2.Add(y2, p384B)
+}
+
+func p384CheckOnCurve(x, y *fiat.P384Element) error {
+	// y² = x³ - 3x + b
+	rhs := p384Polynomial(new(fiat.P384Element), x)
+	lhs := new(fiat.P384Element).Square(y)
+	if rhs.Equal(lhs) != 1 {
+		return errors.New("P384 point not on curve")
+	}
+	return nil
+}
+
+// Bytes returns the uncompressed or infinity encoding of p, as specified in
+// SEC 1, Version 2.0, Section 2.3.3. Note that the encoding of the point at
+// infinity is shorter than all other encodings.
+func (p *P384Point) Bytes() []byte {
+	// This function is outlined to make the allocations inline in the caller
+	// rather than happen on the heap.
+	var out [1 + 2*p384ElementLength]byte
+	return p.bytes(&out)
+}
+
+func (p *P384Point) bytes(out *[1 + 2*p384ElementLength]byte) []byte {
+	if p.z.IsZero() == 1 {
+		return append(out[:0], 0)
+	}
+
+	zinv := new(fiat.P384Element).Invert(p.z)
+	x := new(fiat.P384Element).Mul(p.x, zinv)
+	y := new(fiat.P384Element).Mul(p.y, zinv)
+
+	buf := append(out[:0], 4)
+	buf = append(buf, x.Bytes()...)
+	buf = append(buf, y.Bytes()...)
+	return buf
+}
+
+// BytesCompressed returns the compressed or infinity encoding of p, as
+// specified in SEC 1, Version 2.0, Section 2.3.3. Note that the encoding of the
+// point at infinity is shorter than all other encodings.
+func (p *P384Point) BytesCompressed() []byte {
+	// This function is outlined to make the allocations inline in the caller
+	// rather than happen on the heap.
+	var out [1 + p384ElementLength]byte
+	return p.bytesCompressed(&out)
+}
+
+func (p *P384Point) bytesCompressed(out *[1 + p384ElementLength]byte) []byte {
+	if p.z.IsZero() == 1 {
+		return append(out[:0], 0)
+	}
+
+	zinv := new(fiat.P384Element).Invert(p.z)
+	x := new(fiat.P384Element).Mul(p.x, zinv)
+	y := new(fiat.P384Element).Mul(p.y, zinv)
+
+	// Encode the sign of the y coordinate (indicated by the least significant
+	// bit) as the encoding type (2 or 3).
+	buf := append(out[:0], 2)
+	buf[0] |= y.Bytes()[p384ElementLength-1] & 1
+	buf = append(buf, x.Bytes()...)
+	return buf
+}
+
+// Add sets q = p1 + p2, and returns q. The points may overlap.
+func (q *P384Point) Add(p1, p2 *P384Point) *P384Point {
+	// Complete addition formula for a = -3 from "Complete addition formulas for
+	// prime order elliptic curves" (https://eprint.iacr.org/2015/1060), §A.2.
+
+	t0 := new(fiat.P384Element).Mul(p1.x, p2.x) // t0 := X1 * X2
+	t1 := new(fiat.P384Element).Mul(p1.y, p2.y) // t1 := Y1 * Y2
+	t2 := new(fiat.P384Element).Mul(p1.z, p2.z) // t2 := Z1 * Z2
+	t3 := new(fiat.P384Element).Add(p1.x, p1.y) // t3 := X1 + Y1
+	t4 := new(fiat.P384Element).Add(p2.x, p2.y) // t4 := X2 + Y2
+	t3.Mul(t3, t4)                              // t3 := t3 * t4
+	t4.Add(t0, t1)                              // t4 := t0 + t1
+	t3.Sub(t3, t4)                              // t3 := t3 - t4
+	t4.Add(p1.y, p1.z)                          // t4 := Y1 + Z1
+	x3 := new(fiat.P384Element).Add(p2.y, p2.z) // X3 := Y2 + Z2
+	t4.Mul(t4, x3)                              // t4 := t4 * X3
+	x3.Add(t1, t2)                              // X3 := t1 + t2
+	t4.Sub(t4, x3)                              // t4 := t4 - X3
+	x3.Add(p1.x, p1.z)                          // X3 := X1 + Z1
+	y3 := new(fiat.P384Element).Add(p2.x, p2.z) // Y3 := X2 + Z2
+	x3.Mul(x3, y3)                              // X3 := X3 * Y3
+	y3.Add(t0, t2)                              // Y3 := t0 + t2
+	y3.Sub(x3, y3)                              // Y3 := X3 - Y3
+	z3 := new(fiat.P384Element).Mul(p384B, t2)  // Z3 := b * t2
+	x3.Sub(y3, z3)                              // X3 := Y3 - Z3
+	z3.Add(x3, x3)                              // Z3 := X3 + X3
+	x3.Add(x3, z3)                              // X3 := X3 + Z3
+	z3.Sub(t1, x3)                              // Z3 := t1 - X3
+	x3.Add(t1, x3)                              // X3 := t1 + X3
+	y3.Mul(p384B, y3)                           // Y3 := b * Y3
+	t1.Add(t2, t2)                              // t1 := t2 + t2
+	t2.Add(t1, t2)                              // t2 := t1 + t2
+	y3.Sub(y3, t2)                              // Y3 := Y3 - t2
+	y3.Sub(y3, t0)                              // Y3 := Y3 - t0
+	t1.Add(y3, y3)                              // t1 := Y3 + Y3
+	y3.Add(t1, y3)                              // Y3 := t1 + Y3
+	t1.Add(t0, t0)                              // t1 := t0 + t0
+	t0.Add(t1, t0)                              // t0 := t1 + t0
+	t0.Sub(t0, t2)                              // t0 := t0 - t2
+	t1.Mul(t4, y3)                              // t1 := t4 * Y3
+	t2.Mul(t0, y3)                              // t2 := t0 * Y3
+	y3.Mul(x3, z3)                              // Y3 := X3 * Z3
+	y3.Add(y3, t2)                              // Y3 := Y3 + t2
+	x3.Mul(t3, x3)                              // X3 := t3 * X3
+	x3.Sub(x3, t1)                              // X3 := X3 - t1
+	z3.Mul(t4, z3)                              // Z3 := t4 * Z3
+	t1.Mul(t3, t0)                              // t1 := t3 * t0
+	z3.Add(z3, t1)                              // Z3 := Z3 + t1
+
+	q.x.Set(x3)
+	q.y.Set(y3)
+	q.z.Set(z3)
+	return q
+}
+
+// Double sets q = p + p, and returns q. The points may overlap.
+func (q *P384Point) Double(p *P384Point) *P384Point {
+	// Complete addition formula for a = -3 from "Complete addition formulas for
+	// prime order elliptic curves" (https://eprint.iacr.org/2015/1060), §A.2.
+
+	t0 := new(fiat.P384Element).Square(p.x)    // t0 := X ^ 2
+	t1 := new(fiat.P384Element).Square(p.y)    // t1 := Y ^ 2
+	t2 := new(fiat.P384Element).Square(p.z)    // t2 := Z ^ 2
+	t3 := new(fiat.P384Element).Mul(p.x, p.y)  // t3 := X * Y
+	t3.Add(t3, t3)                             // t3 := t3 + t3
+	z3 := new(fiat.P384Element).Mul(p.x, p.z)  // Z3 := X * Z
+	z3.Add(z3, z3)                             // Z3 := Z3 + Z3
+	y3 := new(fiat.P384Element).Mul(p384B, t2) // Y3 := b * t2
+	y3.Sub(y3, z3)                             // Y3 := Y3 - Z3
+	x3 := new(fiat.P384Element).Add(y3, y3)    // X3 := Y3 + Y3
+	y3.Add(x3, y3)                             // Y3 := X3 + Y3
+	x3.Sub(t1, y3)                             // X3 := t1 - Y3
+	y3.Add(t1, y3)                             // Y3 := t1 + Y3
+	y3.Mul(x3, y3)                             // Y3 := X3 * Y3
+	x3.Mul(x3, t3)                             // X3 := X3 * t3
+	t3.Add(t2, t2)                             // t3 := t2 + t2
+	t2.Add(t2, t3)                             // t2 := t2 + t3
+	z3.Mul(p384B, z3)                          // Z3 := b * Z3
+	z3.Sub(z3, t2)                             // Z3 := Z3 - t2
+	z3.Sub(z3, t0)                             // Z3 := Z3 - t0
+	t3.Add(z3, z3)                             // t3 := Z3 + Z3
+	z3.Add(z3, t3)                             // Z3 := Z3 + t3
+	t3.Add(t0, t0)                             // t3 := t0 + t0
+	t0.Add(t3, t0)                             // t0 := t3 + t0
+	t0.Sub(t0, t2)                             // t0 := t0 - t2
+	t0.Mul(t0, z3)                             // t0 := t0 * Z3
+	y3.Add(y3, t0)                             // Y3 := Y3 + t0
+	t0.Mul(p.y, p.z)                           // t0 := Y * Z
+	t0.Add(t0, t0)                             // t0 := t0 + t0
+	z3.Mul(t0, z3)                             // Z3 := t0 * Z3
+	x3.Sub(x3, z3)                             // X3 := X3 - Z3
+	z3.Mul(t0, t1)                             // Z3 := t0 * t1
+	z3.Add(z3, z3)                             // Z3 := Z3 + Z3
+	z3.Add(z3, z3)                             // Z3 := Z3 + Z3
+
+	q.x.Set(x3)
+	q.y.Set(y3)
+	q.z.Set(z3)
+	return q
+}
+
+// Select sets q to p1 if cond == 1, and to p2 if cond == 0.
+func (q *P384Point) Select(p1, p2 *P384Point, cond int) *P384Point {
+	q.x.Select(p1.x, p2.x, cond)
+	q.y.Select(p1.y, p2.y, cond)
+	q.z.Select(p1.z, p2.z, cond)
+	return q
+}
+
+// A p384Table holds the first 15 multiples of a point at offset -1, so [1]P
+// is at table[0], [15]P is at table[14], and [0]P is implicitly the identity
+// point.
+type p384Table [15]*P384Point
+
+// Select selects the n-th multiple of the table base point into p. It works in
+// constant time by iterating over every entry of the table. n must be in [0, 15].
+func (table *p384Table) Select(p *P384Point, n uint8) {
+	if n >= 16 {
+		panic("nistec: internal error: p384Table called with out-of-bounds value")
+	}
+	p.Set(NewP384Point())
+	for i := uint8(1); i < 16; i++ {
+		cond := subtle.ConstantTimeByteEq(i, n)
+		p.Select(table[i-1], p, cond)
+	}
+}
+
+// ScalarMult sets p = scalar * q, and returns p.
+func (p *P384Point) ScalarMult(q *P384Point, scalar []byte) (*P384Point, error) {
+	// Compute a p384Table for the base point q. The explicit NewP384Point
+	// calls get inlined, letting the allocations live on the stack.
+	var table = p384Table{NewP384Point(), NewP384Point(), NewP384Point(),
+		NewP384Point(), NewP384Point(), NewP384Point(), NewP384Point(),
+		NewP384Point(), NewP384Point(), NewP384Point(), NewP384Point(),
+		NewP384Point(), NewP384Point(), NewP384Point(), NewP384Point()}
+	table[0].Set(q)
+	for i := 1; i < 15; i += 2 {
+		table[i].Double(table[i/2])
+		table[i+1].Add(table[i], q)
+	}
+
+	// Instead of doing the classic double-and-add chain, we do it with a
+	// four-bit window: we double four times, and then add [0-15]P.
+	t := NewP384Point()
+	p.Set(NewP384Point())
+	for i, byte := range scalar {
+		// No need to double on the first iteration, as p is the identity at
+		// this point, and [N]∞ = ∞.
+		if i != 0 {
+			p.Double(p)
+			p.Double(p)
+			p.Double(p)
+			p.Double(p)
+		}
+
+		windowValue := byte >> 4
+		table.Select(t, windowValue)
+		p.Add(p, t)
+
+		p.Double(p)
+		p.Double(p)
+		p.Double(p)
+		p.Double(p)
+
+		windowValue = byte & 0b1111
+		table.Select(t, windowValue)
+		p.Add(p, t)
+	}
+
+	return p, nil
+}
+
+var p384GeneratorTable *[p384ElementLength * 2]p384Table
+var p384GeneratorTableOnce sync.Once
+
+// generatorTable returns a sequence of p384Tables. The first table contains
+// multiples of G. Each successive table is the previous table doubled four
+// times.
+func (p *P384Point) generatorTable() *[p384ElementLength * 2]p384Table {
+	p384GeneratorTableOnce.Do(func() {
+		p384GeneratorTable = new([p384ElementLength * 2]p384Table)
+		base := NewP384Generator()
+		for i := 0; i < p384ElementLength*2; i++ {
+			p384GeneratorTable[i][0] = NewP384Point().Set(base)
+			for j := 1; j < 15; j++ {
+				p384GeneratorTable[i][j] = NewP384Point().Add(p384GeneratorTable[i][j-1], base)
+			}
+			base.Double(base)
+			base.Double(base)
+			base.Double(base)
+			base.Double(base)
+		}
+	})
+	return p384GeneratorTable
+}
+
+// ScalarBaseMult sets p = scalar * B, where B is the canonical generator, and
+// returns p.
+func (p *P384Point) ScalarBaseMult(scalar []byte) (*P384Point, error) {
+	if len(scalar) != p384ElementLength {
+		return nil, errors.New("invalid scalar length")
+	}
+	tables := p.generatorTable()
+
+	// This is also a scalar multiplication with a four-bit window like in
+	// ScalarMult, but in this case the doublings are precomputed. The value
+	// [windowValue]G added at iteration k would normally get doubled
+	// (totIterations-k)×4 times, but with a larger precomputation we can
+	// instead add [2^((totIterations-k)×4)][windowValue]G and avoid the
+	// doublings between iterations.
+	t := NewP384Point()
+	p.Set(NewP384Point())
+	tableIndex := len(tables) - 1
+	for _, byte := range scalar {
+		windowValue := byte >> 4
+		tables[tableIndex].Select(t, windowValue)
+		p.Add(p, t)
+		tableIndex--
+
+		windowValue = byte & 0b1111
+		tables[tableIndex].Select(t, windowValue)
+		p.Add(p, t)
+		tableIndex--
+	}
+
+	return p, nil
+}
+
+// p384Sqrt sets e to a square root of x. If x is not a square, p384Sqrt returns
+// false and e is unchanged. e and x can overlap.
+func p384Sqrt(e, x *fiat.P384Element) (isSquare bool) {
+	candidate := new(fiat.P384Element)
+	p384SqrtCandidate(candidate, x)
+	square := new(fiat.P384Element).Square(candidate)
+	if square.Equal(x) != 1 {
+		return false
+	}
+	e.Set(candidate)
+	return true
+}
+
+// p384SqrtCandidate sets z to a square root candidate for x. z and x must not overlap.
+func p384SqrtCandidate(z, x *fiat.P384Element) {
+	// Since p = 3 mod 4, exponentiation by (p + 1) / 4 yields a square root candidate.
+	//
+	// The sequence of 14 multiplications and 381 squarings is derived from the
+	// following addition chain generated with github.com/mmcloughlin/addchain v0.4.0.
+	//
+	//	_10      = 2*1
+	//	_11      = 1 + _10
+	//	_110     = 2*_11
+	//	_111     = 1 + _110
+	//	_111000  = _111 << 3
+	//	_111111  = _111 + _111000
+	//	_1111110 = 2*_111111
+	//	_1111111 = 1 + _1111110
+	//	x12      = _1111110 << 5 + _111111
+	//	x24      = x12 << 12 + x12
+	//	x31      = x24 << 7 + _1111111
+	//	x32      = 2*x31 + 1
+	//	x63      = x32 << 31 + x31
+	//	x126     = x63 << 63 + x63
+	//	x252     = x126 << 126 + x126
+	//	x255     = x252 << 3 + _111
+	//	return     ((x255 << 33 + x32) << 64 + 1) << 30
+	//
+	var t0 = new(fiat.P384Element)
+	var t1 = new(fiat.P384Element)
+	var t2 = new(fiat.P384Element)
+
+	z.Square(x)
+	z.Mul(x, z)
+	z.Square(z)
+	t0.Mul(x, z)
+	z.Square(t0)
+	for s := 1; s < 3; s++ {
+		z.Square(z)
+	}
+	t1.Mul(t0, z)
+	t2.Square(t1)
+	z.Mul(x, t2)
+	for s := 0; s < 5; s++ {
+		t2.Square(t2)
+	}
+	t1.Mul(t1, t2)
+	t2.Square(t1)
+	for s := 1; s < 12; s++ {
+		t2.Square(t2)
+	}
+	t1.Mul(t1, t2)
+	for s := 0; s < 7; s++ {
+		t1.Square(t1)
+	}
+	t1.Mul(z, t1)
+	z.Square(t1)
+	z.Mul(x, z)
+	t2.Square(z)
+	for s := 1; s < 31; s++ {
+		t2.Square(t2)
+	}
+	t1.Mul(t1, t2)
+	t2.Square(t1)
+	for s := 1; s < 63; s++ {
+		t2.Square(t2)
+	}
+	t1.Mul(t1, t2)
+	t2.Square(t1)
+	for s := 1; s < 126; s++ {
+		t2.Square(t2)
+	}
+	t1.Mul(t1, t2)
+	for s := 0; s < 3; s++ {
+		t1.Square(t1)
+	}
+	t0.Mul(t0, t1)
+	for s := 0; s < 33; s++ {
+		t0.Square(t0)
+	}
+	z.Mul(z, t0)
+	for s := 0; s < 64; s++ {
+		z.Square(z)
+	}
+	z.Mul(x, z)
+	for s := 0; s < 30; s++ {
+		z.Square(z)
+	}
+}
diff --git a/contrib/go/_std_1.19/src/crypto/internal/nistec/p521.go b/contrib/go/_std_1.19/src/crypto/internal/nistec/p521.go
new file mode 100644
index 0000000000..f285d57576
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/internal/nistec/p521.go
@@ -0,0 +1,444 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Code generated by generate.go. DO NOT EDIT.
+
+package nistec
+
+import (
+	"crypto/internal/nistec/fiat"
+	"crypto/subtle"
+	"errors"
+	"sync"
+)
+
+var p521B, _ = new(fiat.P521Element).SetBytes([]byte{0x0, 0x51, 0x95, 0x3e, 0xb9, 0x61, 0x8e, 0x1c, 0x9a, 0x1f, 0x92, 0x9a, 0x21, 0xa0, 0xb6, 0x85, 0x40, 0xee, 0xa2, 0xda, 0x72, 0x5b, 0x99, 0xb3, 0x15, 0xf3, 0xb8, 0xb4, 0x89, 0x91, 0x8e, 0xf1, 0x9, 0xe1, 0x56, 0x19, 0x39, 0x51, 0xec, 0x7e, 0x93, 0x7b, 0x16, 0x52, 0xc0, 0xbd, 0x3b, 0xb1, 0xbf, 0x7, 0x35, 0x73, 0xdf, 0x88, 0x3d, 0x2c, 0x34, 0xf1, 0xef, 0x45, 0x1f, 0xd4, 0x6b, 0x50, 0x3f, 0x0})
+
+var p521G, _ = NewP521Point().SetBytes([]byte{0x4, 0x0, 0xc6, 0x85, 0x8e, 0x6, 0xb7, 0x4, 0x4, 0xe9, 0xcd, 0x9e, 0x3e, 0xcb, 0x66, 0x23, 0x95, 0xb4, 0x42, 0x9c, 0x64, 0x81, 0x39, 0x5, 0x3f, 0xb5, 0x21, 0xf8, 0x28, 0xaf, 0x60, 0x6b, 0x4d, 0x3d, 0xba, 0xa1, 0x4b, 0x5e, 0x77, 0xef, 0xe7, 0x59, 0x28, 0xfe, 0x1d, 0xc1, 0x27, 0xa2, 0xff, 0xa8, 0xde, 0x33, 0x48, 0xb3, 0xc1, 0x85, 0x6a, 0x42, 0x9b, 0xf9, 0x7e, 0x7e, 0x31, 0xc2, 0xe5, 0xbd, 0x66, 0x1, 0x18, 0x39, 0x29, 0x6a, 0x78, 0x9a, 0x3b, 0xc0, 0x4, 0x5c, 0x8a, 0x5f, 0xb4, 0x2c, 0x7d, 0x1b, 0xd9, 0x98, 0xf5, 0x44, 0x49, 0x57, 0x9b, 0x44, 0x68, 0x17, 0xaf, 0xbd, 0x17, 0x27, 0x3e, 0x66, 0x2c, 0x97, 0xee, 0x72, 0x99, 0x5e, 0xf4, 0x26, 0x40, 0xc5, 0x50, 0xb9, 0x1, 0x3f, 0xad, 0x7, 0x61, 0x35, 0x3c, 0x70, 0x86, 0xa2, 0x72, 0xc2, 0x40, 0x88, 0xbe, 0x94, 0x76, 0x9f, 0xd1, 0x66, 0x50})
+
+// p521ElementLength is the length of an element of the base or scalar field,
+// which have the same bytes length for all NIST P curves.
+const p521ElementLength = 66
+
+// P521Point is a P521 point. The zero value is NOT valid.
+type P521Point struct {
+	// The point is represented in projective coordinates (X:Y:Z),
+	// where x = X/Z and y = Y/Z.
+	x, y, z *fiat.P521Element
+}
+
+// NewP521Point returns a new P521Point representing the point at infinity point.
+func NewP521Point() *P521Point {
+	return &P521Point{
+		x: new(fiat.P521Element),
+		y: new(fiat.P521Element).One(),
+		z: new(fiat.P521Element),
+	}
+}
+
+// NewP521Generator returns a new P521Point set to the canonical generator.
+func NewP521Generator() *P521Point {
+	return (&P521Point{
+		x: new(fiat.P521Element),
+		y: new(fiat.P521Element),
+		z: new(fiat.P521Element),
+	}).Set(p521G)
+}
+
+// Set sets p = q and returns p.
+func (p *P521Point) Set(q *P521Point) *P521Point {
+	p.x.Set(q.x)
+	p.y.Set(q.y)
+	p.z.Set(q.z)
+	return p
+}
+
+// SetBytes sets p to the compressed, uncompressed, or infinity value encoded in
+// b, as specified in SEC 1, Version 2.0, Section 2.3.4. If the point is not on
+// the curve, it returns nil and an error, and the receiver is unchanged.
+// Otherwise, it returns p.
+func (p *P521Point) SetBytes(b []byte) (*P521Point, error) {
+	switch {
+	// Point at infinity.
+	case len(b) == 1 && b[0] == 0:
+		return p.Set(NewP521Point()), nil
+
+	// Uncompressed form.
+	case len(b) == 1+2*p521ElementLength && b[0] == 4:
+		x, err := new(fiat.P521Element).SetBytes(b[1 : 1+p521ElementLength])
+		if err != nil {
+			return nil, err
+		}
+		y, err := new(fiat.P521Element).SetBytes(b[1+p521ElementLength:])
+		if err != nil {
+			return nil, err
+		}
+		if err := p521CheckOnCurve(x, y); err != nil {
+			return nil, err
+		}
+		p.x.Set(x)
+		p.y.Set(y)
+		p.z.One()
+		return p, nil
+
+	// Compressed form.
+	case len(b) == 1+p521ElementLength && (b[0] == 2 || b[0] == 3):
+		x, err := new(fiat.P521Element).SetBytes(b[1:])
+		if err != nil {
+			return nil, err
+		}
+
+		// y² = x³ - 3x + b
+		y := p521Polynomial(new(fiat.P521Element), x)
+		if !p521Sqrt(y, y) {
+			return nil, errors.New("invalid P521 compressed point encoding")
+		}
+
+		// Select the positive or negative root, as indicated by the least
+		// significant bit, based on the encoding type byte.
+		otherRoot := new(fiat.P521Element)
+		otherRoot.Sub(otherRoot, y)
+		cond := y.Bytes()[p521ElementLength-1]&1 ^ b[0]&1
+		y.Select(otherRoot, y, int(cond))
+
+		p.x.Set(x)
+		p.y.Set(y)
+		p.z.One()
+		return p, nil
+
+	default:
+		return nil, errors.New("invalid P521 point encoding")
+	}
+}
+
+// p521Polynomial sets y2 to x³ - 3x + b, and returns y2.
+func p521Polynomial(y2, x *fiat.P521Element) *fiat.P521Element {
+	y2.Square(x)
+	y2.Mul(y2, x)
+
+	threeX := new(fiat.P521Element).Add(x, x)
+	threeX.Add(threeX, x)
+
+	y2.Sub(y2, threeX)
+	return y2.Add(y2, p521B)
+}
+
+func p521CheckOnCurve(x, y *fiat.P521Element) error {
+	// y² = x³ - 3x + b
+	rhs := p521Polynomial(new(fiat.P521Element), x)
+	lhs := new(fiat.P521Element).Square(y)
+	if rhs.Equal(lhs) != 1 {
+		return errors.New("P521 point not on curve")
+	}
+	return nil
+}
+
+// Bytes returns the uncompressed or infinity encoding of p, as specified in
+// SEC 1, Version 2.0, Section 2.3.3. Note that the encoding of the point at
+// infinity is shorter than all other encodings.
+func (p *P521Point) Bytes() []byte {
+	// This function is outlined to make the allocations inline in the caller
+	// rather than happen on the heap.
+	var out [1 + 2*p521ElementLength]byte
+	return p.bytes(&out)
+}
+
+func (p *P521Point) bytes(out *[1 + 2*p521ElementLength]byte) []byte {
+	if p.z.IsZero() == 1 {
+		return append(out[:0], 0)
+	}
+
+	zinv := new(fiat.P521Element).Invert(p.z)
+	x := new(fiat.P521Element).Mul(p.x, zinv)
+	y := new(fiat.P521Element).Mul(p.y, zinv)
+
+	buf := append(out[:0], 4)
+	buf = append(buf, x.Bytes()...)
+	buf = append(buf, y.Bytes()...)
+	return buf
+}
+
+// BytesCompressed returns the compressed or infinity encoding of p, as
+// specified in SEC 1, Version 2.0, Section 2.3.3. Note that the encoding of the
+// point at infinity is shorter than all other encodings.
+func (p *P521Point) BytesCompressed() []byte {
+	// This function is outlined to make the allocations inline in the caller
+	// rather than happen on the heap.
+	var out [1 + p521ElementLength]byte
+	return p.bytesCompressed(&out)
+}
+
+func (p *P521Point) bytesCompressed(out *[1 + p521ElementLength]byte) []byte {
+	if p.z.IsZero() == 1 {
+		return append(out[:0], 0)
+	}
+
+	zinv := new(fiat.P521Element).Invert(p.z)
+	x := new(fiat.P521Element).Mul(p.x, zinv)
+	y := new(fiat.P521Element).Mul(p.y, zinv)
+
+	// Encode the sign of the y coordinate (indicated by the least significant
+	// bit) as the encoding type (2 or 3).
+	buf := append(out[:0], 2)
+	buf[0] |= y.Bytes()[p521ElementLength-1] & 1
+	buf = append(buf, x.Bytes()...)
+	return buf
+}
+
+// Add sets q = p1 + p2, and returns q. The points may overlap.
+func (q *P521Point) Add(p1, p2 *P521Point) *P521Point {
+	// Complete addition formula for a = -3 from "Complete addition formulas for
+	// prime order elliptic curves" (https://eprint.iacr.org/2015/1060), §A.2.
+
+	t0 := new(fiat.P521Element).Mul(p1.x, p2.x) // t0 := X1 * X2
+	t1 := new(fiat.P521Element).Mul(p1.y, p2.y) // t1 := Y1 * Y2
+	t2 := new(fiat.P521Element).Mul(p1.z, p2.z) // t2 := Z1 * Z2
+	t3 := new(fiat.P521Element).Add(p1.x, p1.y) // t3 := X1 + Y1
+	t4 := new(fiat.P521Element).Add(p2.x, p2.y) // t4 := X2 + Y2
+	t3.Mul(t3, t4)                              // t3 := t3 * t4
+	t4.Add(t0, t1)                              // t4 := t0 + t1
+	t3.Sub(t3, t4)                              // t3 := t3 - t4
+	t4.Add(p1.y, p1.z)                          // t4 := Y1 + Z1
+	x3 := new(fiat.P521Element).Add(p2.y, p2.z) // X3 := Y2 + Z2
+	t4.Mul(t4, x3)                              // t4 := t4 * X3
+	x3.Add(t1, t2)                              // X3 := t1 + t2
+	t4.Sub(t4, x3)                              // t4 := t4 - X3
+	x3.Add(p1.x, p1.z)                          // X3 := X1 + Z1
+	y3 := new(fiat.P521Element).Add(p2.x, p2.z) // Y3 := X2 + Z2
+	x3.Mul(x3, y3)                              // X3 := X3 * Y3
+	y3.Add(t0, t2)                              // Y3 := t0 + t2
+	y3.Sub(x3, y3)                              // Y3 := X3 - Y3
+	z3 := new(fiat.P521Element).Mul(p521B, t2)  // Z3 := b * t2
+	x3.Sub(y3, z3)                              // X3 := Y3 - Z3
+	z3.Add(x3, x3)                              // Z3 := X3 + X3
+	x3.Add(x3, z3)                              // X3 := X3 + Z3
+	z3.Sub(t1, x3)                              // Z3 := t1 - X3
+	x3.Add(t1, x3)                              // X3 := t1 + X3
+	y3.Mul(p521B, y3)                           // Y3 := b * Y3
+	t1.Add(t2, t2)                              // t1 := t2 + t2
+	t2.Add(t1, t2)                              // t2 := t1 + t2
+	y3.Sub(y3, t2)                              // Y3 := Y3 - t2
+	y3.Sub(y3, t0)                              // Y3 := Y3 - t0
+	t1.Add(y3, y3)                              // t1 := Y3 + Y3
+	y3.Add(t1, y3)                              // Y3 := t1 + Y3
+	t1.Add(t0, t0)                              // t1 := t0 + t0
+	t0.Add(t1, t0)                              // t0 := t1 + t0
+	t0.Sub(t0, t2)                              // t0 := t0 - t2
+	t1.Mul(t4, y3)                              // t1 := t4 * Y3
+	t2.Mul(t0, y3)                              // t2 := t0 * Y3
+	y3.Mul(x3, z3)                              // Y3 := X3 * Z3
+	y3.Add(y3, t2)                              // Y3 := Y3 + t2
+	x3.Mul(t3, x3)                              // X3 := t3 * X3
+	x3.Sub(x3, t1)                              // X3 := X3 - t1
+	z3.Mul(t4, z3)                              // Z3 := t4 * Z3
+	t1.Mul(t3, t0)                              // t1 := t3 * t0
+	z3.Add(z3, t1)                              // Z3 := Z3 + t1
+
+	q.x.Set(x3)
+	q.y.Set(y3)
+	q.z.Set(z3)
+	return q
+}
+
+// Double sets q = p + p, and returns q. The points may overlap.
+func (q *P521Point) Double(p *P521Point) *P521Point {
+	// Complete addition formula for a = -3 from "Complete addition formulas for
+	// prime order elliptic curves" (https://eprint.iacr.org/2015/1060), §A.2.
+
+	t0 := new(fiat.P521Element).Square(p.x)    // t0 := X ^ 2
+	t1 := new(fiat.P521Element).Square(p.y)    // t1 := Y ^ 2
+	t2 := new(fiat.P521Element).Square(p.z)    // t2 := Z ^ 2
+	t3 := new(fiat.P521Element).Mul(p.x, p.y)  // t3 := X * Y
+	t3.Add(t3, t3)                             // t3 := t3 + t3
+	z3 := new(fiat.P521Element).Mul(p.x, p.z)  // Z3 := X * Z
+	z3.Add(z3, z3)                             // Z3 := Z3 + Z3
+	y3 := new(fiat.P521Element).Mul(p521B, t2) // Y3 := b * t2
+	y3.Sub(y3, z3)                             // Y3 := Y3 - Z3
+	x3 := new(fiat.P521Element).Add(y3, y3)    // X3 := Y3 + Y3
+	y3.Add(x3, y3)                             // Y3 := X3 + Y3
+	x3.Sub(t1, y3)                             // X3 := t1 - Y3
+	y3.Add(t1, y3)                             // Y3 := t1 + Y3
+	y3.Mul(x3, y3)                             // Y3 := X3 * Y3
+	x3.Mul(x3, t3)                             // X3 := X3 * t3
+	t3.Add(t2, t2)                             // t3 := t2 + t2
+	t2.Add(t2, t3)                             // t2 := t2 + t3
+	z3.Mul(p521B, z3)                          // Z3 := b * Z3
+	z3.Sub(z3, t2)                             // Z3 := Z3 - t2
+	z3.Sub(z3, t0)                             // Z3 := Z3 - t0
+	t3.Add(z3, z3)                             // t3 := Z3 + Z3
+	z3.Add(z3, t3)                             // Z3 := Z3 + t3
+	t3.Add(t0, t0)                             // t3 := t0 + t0
+	t0.Add(t3, t0)                             // t0 := t3 + t0
+	t0.Sub(t0, t2)                             // t0 := t0 - t2
+	t0.Mul(t0, z3)                             // t0 := t0 * Z3
+	y3.Add(y3, t0)                             // Y3 := Y3 + t0
+	t0.Mul(p.y, p.z)                           // t0 := Y * Z
+	t0.Add(t0, t0)                             // t0 := t0 + t0
+	z3.Mul(t0, z3)                             // Z3 := t0 * Z3
+	x3.Sub(x3, z3)                             // X3 := X3 - Z3
+	z3.Mul(t0, t1)                             // Z3 := t0 * t1
+	z3.Add(z3, z3)                             // Z3 := Z3 + Z3
+	z3.Add(z3, z3)                             // Z3 := Z3 + Z3
+
+	q.x.Set(x3)
+	q.y.Set(y3)
+	q.z.Set(z3)
+	return q
+}
+
+// Select sets q to p1 if cond == 1, and to p2 if cond == 0.
+func (q *P521Point) Select(p1, p2 *P521Point, cond int) *P521Point {
+	q.x.Select(p1.x, p2.x, cond)
+	q.y.Select(p1.y, p2.y, cond)
+	q.z.Select(p1.z, p2.z, cond)
+	return q
+}
+
+// A p521Table holds the first 15 multiples of a point at offset -1, so [1]P
+// is at table[0], [15]P is at table[14], and [0]P is implicitly the identity
+// point.
+type p521Table [15]*P521Point
+
+// Select selects the n-th multiple of the table base point into p. It works in
+// constant time by iterating over every entry of the table. n must be in [0, 15].
+func (table *p521Table) Select(p *P521Point, n uint8) {
+	if n >= 16 {
+		panic("nistec: internal error: p521Table called with out-of-bounds value")
+	}
+	p.Set(NewP521Point())
+	for i := uint8(1); i < 16; i++ {
+		cond := subtle.ConstantTimeByteEq(i, n)
+		p.Select(table[i-1], p, cond)
+	}
+}
+
+// ScalarMult sets p = scalar * q, and returns p.
+func (p *P521Point) ScalarMult(q *P521Point, scalar []byte) (*P521Point, error) {
+	// Compute a p521Table for the base point q. The explicit NewP521Point
+	// calls get inlined, letting the allocations live on the stack.
+	var table = p521Table{NewP521Point(), NewP521Point(), NewP521Point(),
+		NewP521Point(), NewP521Point(), NewP521Point(), NewP521Point(),
+		NewP521Point(), NewP521Point(), NewP521Point(), NewP521Point(),
+		NewP521Point(), NewP521Point(), NewP521Point(), NewP521Point()}
+	table[0].Set(q)
+	for i := 1; i < 15; i += 2 {
+		table[i].Double(table[i/2])
+		table[i+1].Add(table[i], q)
+	}
+
+	// Instead of doing the classic double-and-add chain, we do it with a
+	// four-bit window: we double four times, and then add [0-15]P.
+	t := NewP521Point()
+	p.Set(NewP521Point())
+	for i, byte := range scalar {
+		// No need to double on the first iteration, as p is the identity at
+		// this point, and [N]∞ = ∞.
+		if i != 0 {
+			p.Double(p)
+			p.Double(p)
+			p.Double(p)
+			p.Double(p)
+		}
+
+		windowValue := byte >> 4
+		table.Select(t, windowValue)
+		p.Add(p, t)
+
+		p.Double(p)
+		p.Double(p)
+		p.Double(p)
+		p.Double(p)
+
+		windowValue = byte & 0b1111
+		table.Select(t, windowValue)
+		p.Add(p, t)
+	}
+
+	return p, nil
+}
+
+var p521GeneratorTable *[p521ElementLength * 2]p521Table
+var p521GeneratorTableOnce sync.Once
+
+// generatorTable returns a sequence of p521Tables. The first table contains
+// multiples of G. Each successive table is the previous table doubled four
+// times.
+func (p *P521Point) generatorTable() *[p521ElementLength * 2]p521Table {
+	p521GeneratorTableOnce.Do(func() {
+		p521GeneratorTable = new([p521ElementLength * 2]p521Table)
+		base := NewP521Generator()
+		for i := 0; i < p521ElementLength*2; i++ {
+			p521GeneratorTable[i][0] = NewP521Point().Set(base)
+			for j := 1; j < 15; j++ {
+				p521GeneratorTable[i][j] = NewP521Point().Add(p521GeneratorTable[i][j-1], base)
+			}
+			base.Double(base)
+			base.Double(base)
+			base.Double(base)
+			base.Double(base)
+		}
+	})
+	return p521GeneratorTable
+}
+
+// ScalarBaseMult sets p = scalar * B, where B is the canonical generator, and
+// returns p.
+func (p *P521Point) ScalarBaseMult(scalar []byte) (*P521Point, error) {
+	if len(scalar) != p521ElementLength {
+		return nil, errors.New("invalid scalar length")
+	}
+	tables := p.generatorTable()
+
+	// This is also a scalar multiplication with a four-bit window like in
+	// ScalarMult, but in this case the doublings are precomputed. The value
+	// [windowValue]G added at iteration k would normally get doubled
+	// (totIterations-k)×4 times, but with a larger precomputation we can
+	// instead add [2^((totIterations-k)×4)][windowValue]G and avoid the
+	// doublings between iterations.
+	t := NewP521Point()
+	p.Set(NewP521Point())
+	tableIndex := len(tables) - 1
+	for _, byte := range scalar {
+		windowValue := byte >> 4
+		tables[tableIndex].Select(t, windowValue)
+		p.Add(p, t)
+		tableIndex--
+
+		windowValue = byte & 0b1111
+		tables[tableIndex].Select(t, windowValue)
+		p.Add(p, t)
+		tableIndex--
+	}
+
+	return p, nil
+}
+
+// p521Sqrt sets e to a square root of x. If x is not a square, p521Sqrt returns
+// false and e is unchanged. e and x can overlap.
+func p521Sqrt(e, x *fiat.P521Element) (isSquare bool) {
+	candidate := new(fiat.P521Element)
+	p521SqrtCandidate(candidate, x)
+	square := new(fiat.P521Element).Square(candidate)
+	if square.Equal(x) != 1 {
+		return false
+	}
+	e.Set(candidate)
+	return true
+}
+
+// p521SqrtCandidate sets z to a square root candidate for x. z and x must not overlap.
+func p521SqrtCandidate(z, x *fiat.P521Element) {
+	// Since p = 3 mod 4, exponentiation by (p + 1) / 4 yields a square root candidate.
+	//
+	// The sequence of 0 multiplications and 519 squarings is derived from the
+	// following addition chain generated with github.com/mmcloughlin/addchain v0.4.0.
+	//
+	//	return  1 << 519
+	//
+
+	z.Square(x)
+	for s := 1; s < 519; s++ {
+		z.Square(z)
+	}
+}
diff --git a/contrib/go/_std_1.18/src/crypto/internal/randutil/randutil.go b/contrib/go/_std_1.19/src/crypto/internal/randutil/randutil.go
index 84b1295a87..84b1295a87 100644
--- a/contrib/go/_std_1.18/src/crypto/internal/randutil/randutil.go
+++ b/contrib/go/_std_1.19/src/crypto/internal/randutil/randutil.go
diff --git a/contrib/go/_std_1.18/src/crypto/internal/subtle/aliasing.go b/contrib/go/_std_1.19/src/crypto/internal/subtle/aliasing.go
index 16e2fcab12..16e2fcab12 100644
--- a/contrib/go/_std_1.18/src/crypto/internal/subtle/aliasing.go
+++ b/contrib/go/_std_1.19/src/crypto/internal/subtle/aliasing.go
diff --git a/contrib/go/_std_1.18/src/crypto/md5/md5.go b/contrib/go/_std_1.19/src/crypto/md5/md5.go
index 0115784047..0115784047 100644
--- a/contrib/go/_std_1.18/src/crypto/md5/md5.go
+++ b/contrib/go/_std_1.19/src/crypto/md5/md5.go
diff --git a/contrib/go/_std_1.18/src/crypto/md5/md5block.go b/contrib/go/_std_1.19/src/crypto/md5/md5block.go
index 4ff289e860..4ff289e860 100644
--- a/contrib/go/_std_1.18/src/crypto/md5/md5block.go
+++ b/contrib/go/_std_1.19/src/crypto/md5/md5block.go
diff --git a/contrib/go/_std_1.18/src/crypto/md5/md5block_amd64.s b/contrib/go/_std_1.19/src/crypto/md5/md5block_amd64.s
index 7c7d92d7e8..7c7d92d7e8 100644
--- a/contrib/go/_std_1.18/src/crypto/md5/md5block_amd64.s
+++ b/contrib/go/_std_1.19/src/crypto/md5/md5block_amd64.s
diff --git a/contrib/go/_std_1.18/src/crypto/md5/md5block_decl.go b/contrib/go/_std_1.19/src/crypto/md5/md5block_decl.go
index 6716a0c9db..6716a0c9db 100644
--- a/contrib/go/_std_1.18/src/crypto/md5/md5block_decl.go
+++ b/contrib/go/_std_1.19/src/crypto/md5/md5block_decl.go
diff --git a/contrib/go/_std_1.18/src/crypto/rand/rand.go b/contrib/go/_std_1.19/src/crypto/rand/rand.go
index af85b966df..af85b966df 100644
--- a/contrib/go/_std_1.18/src/crypto/rand/rand.go
+++ b/contrib/go/_std_1.19/src/crypto/rand/rand.go
diff --git a/contrib/go/_std_1.19/src/crypto/rand/rand_getentropy.go b/contrib/go/_std_1.19/src/crypto/rand/rand_getentropy.go
new file mode 100644
index 0000000000..68f921b0fc
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/rand/rand_getentropy.go
@@ -0,0 +1,14 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build (darwin && !ios) || openbsd
+
+package rand
+
+import "internal/syscall/unix"
+
+func init() {
+	// getentropy(2) returns a maximum of 256 bytes per call
+	altGetRandom = batched(unix.GetEntropy, 256)
+}
diff --git a/contrib/go/_std_1.19/src/crypto/rand/rand_getrandom.go b/contrib/go/_std_1.19/src/crypto/rand/rand_getrandom.go
new file mode 100644
index 0000000000..478aa5c459
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/rand/rand_getrandom.go
@@ -0,0 +1,48 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build linux || freebsd || dragonfly || solaris
+
+package rand
+
+import (
+	"internal/syscall/unix"
+	"runtime"
+	"syscall"
+)
+
+func init() {
+	var maxGetRandomRead int
+	switch runtime.GOOS {
+	case "linux", "android":
+		// Per the manpage:
+		//     When reading from the urandom source, a maximum of 33554431 bytes
+		//     is returned by a single call to getrandom() on systems where int
+		//     has a size of 32 bits.
+		maxGetRandomRead = (1 << 25) - 1
+	case "freebsd", "dragonfly", "solaris", "illumos":
+		maxGetRandomRead = 1 << 8
+	default:
+		panic("no maximum specified for GetRandom")
+	}
+	altGetRandom = batched(getRandom, maxGetRandomRead)
+}
+
+// If the kernel is too old to support the getrandom syscall(),
+// unix.GetRandom will immediately return ENOSYS and we will then fall back to
+// reading from /dev/urandom in rand_unix.go. unix.GetRandom caches the ENOSYS
+// result so we only suffer the syscall overhead once in this case.
+// If the kernel supports the getrandom() syscall, unix.GetRandom will block
+// until the kernel has sufficient randomness (as we don't use GRND_NONBLOCK).
+// In this case, unix.GetRandom will not return an error.
+func getRandom(p []byte) error {
+	n, err := unix.GetRandom(p, 0)
+	if err != nil {
+		return err
+	}
+	if n != len(p) {
+		return syscall.EIO
+	}
+	return nil
+}
diff --git a/contrib/go/_std_1.19/src/crypto/rand/rand_unix.go b/contrib/go/_std_1.19/src/crypto/rand/rand_unix.go
new file mode 100644
index 0000000000..746e90cc91
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/rand/rand_unix.go
@@ -0,0 +1,87 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix
+
+// Unix cryptographically secure pseudorandom number
+// generator.
+
+package rand
+
+import (
+	"crypto/internal/boring"
+	"errors"
+	"io"
+	"os"
+	"sync"
+	"sync/atomic"
+	"syscall"
+	"time"
+)
+
+const urandomDevice = "/dev/urandom"
+
+func init() {
+	if boring.Enabled {
+		Reader = boring.RandReader
+		return
+	}
+	Reader = &reader{}
+}
+
+// A reader satisfies reads by reading from urandomDevice
+type reader struct {
+	f    io.Reader
+	mu   sync.Mutex
+	used uint32 // Atomic: 0 - never used, 1 - used, but f == nil, 2 - used, and f != nil
+}
+
+// altGetRandom if non-nil specifies an OS-specific function to get
+// urandom-style randomness.
+var altGetRandom func([]byte) (err error)
+
+func warnBlocked() {
+	println("crypto/rand: blocked for 60 seconds waiting to read random data from the kernel")
+}
+
+func (r *reader) Read(b []byte) (n int, err error) {
+	boring.Unreachable()
+	if atomic.CompareAndSwapUint32(&r.used, 0, 1) {
+		// First use of randomness. Start timer to warn about
+		// being blocked on entropy not being available.
+		t := time.AfterFunc(time.Minute, warnBlocked)
+		defer t.Stop()
+	}
+	if altGetRandom != nil && altGetRandom(b) == nil {
+		return len(b), nil
+	}
+	if atomic.LoadUint32(&r.used) != 2 {
+		r.mu.Lock()
+		if atomic.LoadUint32(&r.used) != 2 {
+			f, err := os.Open(urandomDevice)
+			if err != nil {
+				r.mu.Unlock()
+				return 0, err
+			}
+			r.f = hideAgainReader{f}
+			atomic.StoreUint32(&r.used, 2)
+		}
+		r.mu.Unlock()
+	}
+	return io.ReadFull(r.f, b)
+}
+
+// hideAgainReader masks EAGAIN reads from /dev/urandom.
+// See golang.org/issue/9205
+type hideAgainReader struct {
+	r io.Reader
+}
+
+func (hr hideAgainReader) Read(p []byte) (n int, err error) {
+	n, err = hr.r.Read(p)
+	if errors.Is(err, syscall.EAGAIN) {
+		err = nil
+	}
+	return
+}
diff --git a/contrib/go/_std_1.19/src/crypto/rand/util.go b/contrib/go/_std_1.19/src/crypto/rand/util.go
new file mode 100644
index 0000000000..11b1a28ec5
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/rand/util.go
@@ -0,0 +1,99 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package rand
+
+import (
+	"crypto/internal/randutil"
+	"errors"
+	"io"
+	"math/big"
+)
+
+// Prime returns a number of the given bit length that is prime with high probability.
+// Prime will return error for any error returned by rand.Read or if bits < 2.
+func Prime(rand io.Reader, bits int) (*big.Int, error) {
+	if bits < 2 {
+		return nil, errors.New("crypto/rand: prime size must be at least 2-bit")
+	}
+
+	randutil.MaybeReadByte(rand)
+
+	b := uint(bits % 8)
+	if b == 0 {
+		b = 8
+	}
+
+	bytes := make([]byte, (bits+7)/8)
+	p := new(big.Int)
+
+	for {
+		if _, err := io.ReadFull(rand, bytes); err != nil {
+			return nil, err
+		}
+
+		// Clear bits in the first byte to make sure the candidate has a size <= bits.
+		bytes[0] &= uint8(int(1<<b) - 1)
+		// Don't let the value be too small, i.e, set the most significant two bits.
+		// Setting the top two bits, rather than just the top bit,
+		// means that when two of these values are multiplied together,
+		// the result isn't ever one bit short.
+		if b >= 2 {
+			bytes[0] |= 3 << (b - 2)
+		} else {
+			// Here b==1, because b cannot be zero.
+			bytes[0] |= 1
+			if len(bytes) > 1 {
+				bytes[1] |= 0x80
+			}
+		}
+		// Make the value odd since an even number this large certainly isn't prime.
+		bytes[len(bytes)-1] |= 1
+
+		p.SetBytes(bytes)
+		if p.ProbablyPrime(20) {
+			return p, nil
+		}
+	}
+}
+
+// Int returns a uniform random value in [0, max). It panics if max <= 0.
+func Int(rand io.Reader, max *big.Int) (n *big.Int, err error) {
+	if max.Sign() <= 0 {
+		panic("crypto/rand: argument to Int is <= 0")
+	}
+	n = new(big.Int)
+	n.Sub(max, n.SetUint64(1))
+	// bitLen is the maximum bit length needed to encode a value < max.
+	bitLen := n.BitLen()
+	if bitLen == 0 {
+		// the only valid result is 0
+		return
+	}
+	// k is the maximum byte length needed to encode a value < max.
+	k := (bitLen + 7) / 8
+	// b is the number of bits in the most significant byte of max-1.
+	b := uint(bitLen % 8)
+	if b == 0 {
+		b = 8
+	}
+
+	bytes := make([]byte, k)
+
+	for {
+		_, err = io.ReadFull(rand, bytes)
+		if err != nil {
+			return nil, err
+		}
+
+		// Clear bits in the first byte to increase the probability
+		// that the candidate is < max.
+		bytes[0] &= uint8(int(1<<b) - 1)
+
+		n.SetBytes(bytes)
+		if n.Cmp(max) < 0 {
+			return
+		}
+	}
+}
diff --git a/contrib/go/_std_1.18/src/crypto/rc4/rc4.go b/contrib/go/_std_1.19/src/crypto/rc4/rc4.go
index c2df0db2dc..c2df0db2dc 100644
--- a/contrib/go/_std_1.18/src/crypto/rc4/rc4.go
+++ b/contrib/go/_std_1.19/src/crypto/rc4/rc4.go
diff --git a/contrib/go/_std_1.19/src/crypto/rsa/notboring.go b/contrib/go/_std_1.19/src/crypto/rsa/notboring.go
new file mode 100644
index 0000000000..2abc043640
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/rsa/notboring.go
@@ -0,0 +1,16 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !boringcrypto
+
+package rsa
+
+import "crypto/internal/boring"
+
+func boringPublicKey(*PublicKey) (*boring.PublicKeyRSA, error) {
+	panic("boringcrypto: not available")
+}
+func boringPrivateKey(*PrivateKey) (*boring.PrivateKeyRSA, error) {
+	panic("boringcrypto: not available")
+}
diff --git a/contrib/go/_std_1.19/src/crypto/rsa/pkcs1v15.go b/contrib/go/_std_1.19/src/crypto/rsa/pkcs1v15.go
new file mode 100644
index 0000000000..ab19229a6c
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/rsa/pkcs1v15.go
@@ -0,0 +1,387 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package rsa
+
+import (
+	"crypto"
+	"crypto/internal/boring"
+	"crypto/internal/randutil"
+	"crypto/subtle"
+	"errors"
+	"io"
+	"math/big"
+)
+
+// This file implements encryption and decryption using PKCS #1 v1.5 padding.
+
+// PKCS1v15DecrypterOpts is for passing options to PKCS #1 v1.5 decryption using
+// the crypto.Decrypter interface.
+type PKCS1v15DecryptOptions struct {
+	// SessionKeyLen is the length of the session key that is being
+	// decrypted. If not zero, then a padding error during decryption will
+	// cause a random plaintext of this length to be returned rather than
+	// an error. These alternatives happen in constant time.
+	SessionKeyLen int
+}
+
+// EncryptPKCS1v15 encrypts the given message with RSA and the padding
+// scheme from PKCS #1 v1.5.  The message must be no longer than the
+// length of the public modulus minus 11 bytes.
+//
+// The random parameter is used as a source of entropy to ensure that
+// encrypting the same message twice doesn't result in the same
+// ciphertext.
+//
+// WARNING: use of this function to encrypt plaintexts other than
+// session keys is dangerous. Use RSA OAEP in new protocols.
+func EncryptPKCS1v15(random io.Reader, pub *PublicKey, msg []byte) ([]byte, error) {
+	randutil.MaybeReadByte(random)
+
+	if err := checkPub(pub); err != nil {
+		return nil, err
+	}
+	k := pub.Size()
+	if len(msg) > k-11 {
+		return nil, ErrMessageTooLong
+	}
+
+	if boring.Enabled && random == boring.RandReader {
+		bkey, err := boringPublicKey(pub)
+		if err != nil {
+			return nil, err
+		}
+		return boring.EncryptRSAPKCS1(bkey, msg)
+	}
+	boring.UnreachableExceptTests()
+
+	// EM = 0x00 || 0x02 || PS || 0x00 || M
+	em := make([]byte, k)
+	em[1] = 2
+	ps, mm := em[2:len(em)-len(msg)-1], em[len(em)-len(msg):]
+	err := nonZeroRandomBytes(ps, random)
+	if err != nil {
+		return nil, err
+	}
+	em[len(em)-len(msg)-1] = 0
+	copy(mm, msg)
+
+	if boring.Enabled {
+		var bkey *boring.PublicKeyRSA
+		bkey, err = boringPublicKey(pub)
+		if err != nil {
+			return nil, err
+		}
+		return boring.EncryptRSANoPadding(bkey, em)
+	}
+
+	m := new(big.Int).SetBytes(em)
+	c := encrypt(new(big.Int), pub, m)
+	return c.FillBytes(em), nil
+}
+
+// DecryptPKCS1v15 decrypts a plaintext using RSA and the padding scheme from PKCS #1 v1.5.
+// If random != nil, it uses RSA blinding to avoid timing side-channel attacks.
+//
+// Note that whether this function returns an error or not discloses secret
+// information. If an attacker can cause this function to run repeatedly and
+// learn whether each instance returned an error then they can decrypt and
+// forge signatures as if they had the private key. See
+// DecryptPKCS1v15SessionKey for a way of solving this problem.
+func DecryptPKCS1v15(random io.Reader, priv *PrivateKey, ciphertext []byte) ([]byte, error) {
+	if err := checkPub(&priv.PublicKey); err != nil {
+		return nil, err
+	}
+
+	if boring.Enabled {
+		bkey, err := boringPrivateKey(priv)
+		if err != nil {
+			return nil, err
+		}
+		out, err := boring.DecryptRSAPKCS1(bkey, ciphertext)
+		if err != nil {
+			return nil, ErrDecryption
+		}
+		return out, nil
+	}
+
+	valid, out, index, err := decryptPKCS1v15(random, priv, ciphertext)
+	if err != nil {
+		return nil, err
+	}
+	if valid == 0 {
+		return nil, ErrDecryption
+	}
+	return out[index:], nil
+}
+
+// DecryptPKCS1v15SessionKey decrypts a session key using RSA and the padding scheme from PKCS #1 v1.5.
+// If random != nil, it uses RSA blinding to avoid timing side-channel attacks.
+// It returns an error if the ciphertext is the wrong length or if the
+// ciphertext is greater than the public modulus. Otherwise, no error is
+// returned. If the padding is valid, the resulting plaintext message is copied
+// into key. Otherwise, key is unchanged. These alternatives occur in constant
+// time. It is intended that the user of this function generate a random
+// session key beforehand and continue the protocol with the resulting value.
+// This will remove any possibility that an attacker can learn any information
+// about the plaintext.
+// See “Chosen Ciphertext Attacks Against Protocols Based on the RSA
+// Encryption Standard PKCS #1”, Daniel Bleichenbacher, Advances in Cryptology
+// (Crypto '98).
+//
+// Note that if the session key is too small then it may be possible for an
+// attacker to brute-force it. If they can do that then they can learn whether
+// a random value was used (because it'll be different for the same ciphertext)
+// and thus whether the padding was correct. This defeats the point of this
+// function. Using at least a 16-byte key will protect against this attack.
+func DecryptPKCS1v15SessionKey(random io.Reader, priv *PrivateKey, ciphertext []byte, key []byte) error {
+	if err := checkPub(&priv.PublicKey); err != nil {
+		return err
+	}
+	k := priv.Size()
+	if k-(len(key)+3+8) < 0 {
+		return ErrDecryption
+	}
+
+	valid, em, index, err := decryptPKCS1v15(random, priv, ciphertext)
+	if err != nil {
+		return err
+	}
+
+	if len(em) != k {
+		// This should be impossible because decryptPKCS1v15 always
+		// returns the full slice.
+		return ErrDecryption
+	}
+
+	valid &= subtle.ConstantTimeEq(int32(len(em)-index), int32(len(key)))
+	subtle.ConstantTimeCopy(valid, key, em[len(em)-len(key):])
+	return nil
+}
+
+// decryptPKCS1v15 decrypts ciphertext using priv and blinds the operation if
+// random is not nil. It returns one or zero in valid that indicates whether the
+// plaintext was correctly structured. In either case, the plaintext is
+// returned in em so that it may be read independently of whether it was valid
+// in order to maintain constant memory access patterns. If the plaintext was
+// valid then index contains the index of the original message in em.
+func decryptPKCS1v15(random io.Reader, priv *PrivateKey, ciphertext []byte) (valid int, em []byte, index int, err error) {
+	k := priv.Size()
+	if k < 11 {
+		err = ErrDecryption
+		return
+	}
+
+	if boring.Enabled {
+		var bkey *boring.PrivateKeyRSA
+		bkey, err = boringPrivateKey(priv)
+		if err != nil {
+			return
+		}
+		em, err = boring.DecryptRSANoPadding(bkey, ciphertext)
+		if err != nil {
+			return
+		}
+	} else {
+		c := new(big.Int).SetBytes(ciphertext)
+		var m *big.Int
+		m, err = decrypt(random, priv, c)
+		if err != nil {
+			return
+		}
+		em = m.FillBytes(make([]byte, k))
+	}
+
+	firstByteIsZero := subtle.ConstantTimeByteEq(em[0], 0)
+	secondByteIsTwo := subtle.ConstantTimeByteEq(em[1], 2)
+
+	// The remainder of the plaintext must be a string of non-zero random
+	// octets, followed by a 0, followed by the message.
+	//   lookingForIndex: 1 iff we are still looking for the zero.
+	//   index: the offset of the first zero byte.
+	lookingForIndex := 1
+
+	for i := 2; i < len(em); i++ {
+		equals0 := subtle.ConstantTimeByteEq(em[i], 0)
+		index = subtle.ConstantTimeSelect(lookingForIndex&equals0, i, index)
+		lookingForIndex = subtle.ConstantTimeSelect(equals0, 0, lookingForIndex)
+	}
+
+	// The PS padding must be at least 8 bytes long, and it starts two
+	// bytes into em.
+	validPS := subtle.ConstantTimeLessOrEq(2+8, index)
+
+	valid = firstByteIsZero & secondByteIsTwo & (^lookingForIndex & 1) & validPS
+	index = subtle.ConstantTimeSelect(valid, index+1, 0)
+	return valid, em, index, nil
+}
+
+// nonZeroRandomBytes fills the given slice with non-zero random octets.
+func nonZeroRandomBytes(s []byte, random io.Reader) (err error) {
+	_, err = io.ReadFull(random, s)
+	if err != nil {
+		return
+	}
+
+	for i := 0; i < len(s); i++ {
+		for s[i] == 0 {
+			_, err = io.ReadFull(random, s[i:i+1])
+			if err != nil {
+				return
+			}
+			// In tests, the PRNG may return all zeros so we do
+			// this to break the loop.
+			s[i] ^= 0x42
+		}
+	}
+
+	return
+}
+
+// These are ASN1 DER structures:
+//
+//	DigestInfo ::= SEQUENCE {
+//	  digestAlgorithm AlgorithmIdentifier,
+//	  digest OCTET STRING
+//	}
+//
+// For performance, we don't use the generic ASN1 encoder. Rather, we
+// precompute a prefix of the digest value that makes a valid ASN1 DER string
+// with the correct contents.
+var hashPrefixes = map[crypto.Hash][]byte{
+	crypto.MD5:       {0x30, 0x20, 0x30, 0x0c, 0x06, 0x08, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x02, 0x05, 0x05, 0x00, 0x04, 0x10},
+	crypto.SHA1:      {0x30, 0x21, 0x30, 0x09, 0x06, 0x05, 0x2b, 0x0e, 0x03, 0x02, 0x1a, 0x05, 0x00, 0x04, 0x14},
+	crypto.SHA224:    {0x30, 0x2d, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x04, 0x05, 0x00, 0x04, 0x1c},
+	crypto.SHA256:    {0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, 0x05, 0x00, 0x04, 0x20},
+	crypto.SHA384:    {0x30, 0x41, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x02, 0x05, 0x00, 0x04, 0x30},
+	crypto.SHA512:    {0x30, 0x51, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03, 0x05, 0x00, 0x04, 0x40},
+	crypto.MD5SHA1:   {}, // A special TLS case which doesn't use an ASN1 prefix.
+	crypto.RIPEMD160: {0x30, 0x20, 0x30, 0x08, 0x06, 0x06, 0x28, 0xcf, 0x06, 0x03, 0x00, 0x31, 0x04, 0x14},
+}
+
+// SignPKCS1v15 calculates the signature of hashed using
+// RSASSA-PKCS1-V1_5-SIGN from RSA PKCS #1 v1.5.  Note that hashed must
+// be the result of hashing the input message using the given hash
+// function. If hash is zero, hashed is signed directly. This isn't
+// advisable except for interoperability.
+//
+// If random is not nil then RSA blinding will be used to avoid timing
+// side-channel attacks.
+//
+// This function is deterministic. Thus, if the set of possible
+// messages is small, an attacker may be able to build a map from
+// messages to signatures and identify the signed messages. As ever,
+// signatures provide authenticity, not confidentiality.
+func SignPKCS1v15(random io.Reader, priv *PrivateKey, hash crypto.Hash, hashed []byte) ([]byte, error) {
+	hashLen, prefix, err := pkcs1v15HashInfo(hash, len(hashed))
+	if err != nil {
+		return nil, err
+	}
+
+	tLen := len(prefix) + hashLen
+	k := priv.Size()
+	if k < tLen+11 {
+		return nil, ErrMessageTooLong
+	}
+
+	if boring.Enabled {
+		bkey, err := boringPrivateKey(priv)
+		if err != nil {
+			return nil, err
+		}
+		return boring.SignRSAPKCS1v15(bkey, hash, hashed)
+	}
+
+	// EM = 0x00 || 0x01 || PS || 0x00 || T
+	em := make([]byte, k)
+	em[1] = 1
+	for i := 2; i < k-tLen-1; i++ {
+		em[i] = 0xff
+	}
+	copy(em[k-tLen:k-hashLen], prefix)
+	copy(em[k-hashLen:k], hashed)
+
+	m := new(big.Int).SetBytes(em)
+	c, err := decryptAndCheck(random, priv, m)
+	if err != nil {
+		return nil, err
+	}
+
+	return c.FillBytes(em), nil
+}
+
+// VerifyPKCS1v15 verifies an RSA PKCS #1 v1.5 signature.
+// hashed is the result of hashing the input message using the given hash
+// function and sig is the signature. A valid signature is indicated by
+// returning a nil error. If hash is zero then hashed is used directly. This
+// isn't advisable except for interoperability.
+func VerifyPKCS1v15(pub *PublicKey, hash crypto.Hash, hashed []byte, sig []byte) error {
+	if boring.Enabled {
+		bkey, err := boringPublicKey(pub)
+		if err != nil {
+			return err
+		}
+		if err := boring.VerifyRSAPKCS1v15(bkey, hash, hashed, sig); err != nil {
+			return ErrVerification
+		}
+		return nil
+	}
+
+	hashLen, prefix, err := pkcs1v15HashInfo(hash, len(hashed))
+	if err != nil {
+		return err
+	}
+
+	tLen := len(prefix) + hashLen
+	k := pub.Size()
+	if k < tLen+11 {
+		return ErrVerification
+	}
+
+	// RFC 8017 Section 8.2.2: If the length of the signature S is not k
+	// octets (where k is the length in octets of the RSA modulus n), output
+	// "invalid signature" and stop.
+	if k != len(sig) {
+		return ErrVerification
+	}
+
+	c := new(big.Int).SetBytes(sig)
+	m := encrypt(new(big.Int), pub, c)
+	em := m.FillBytes(make([]byte, k))
+	// EM = 0x00 || 0x01 || PS || 0x00 || T
+
+	ok := subtle.ConstantTimeByteEq(em[0], 0)
+	ok &= subtle.ConstantTimeByteEq(em[1], 1)
+	ok &= subtle.ConstantTimeCompare(em[k-hashLen:k], hashed)
+	ok &= subtle.ConstantTimeCompare(em[k-tLen:k-hashLen], prefix)
+	ok &= subtle.ConstantTimeByteEq(em[k-tLen-1], 0)
+
+	for i := 2; i < k-tLen-1; i++ {
+		ok &= subtle.ConstantTimeByteEq(em[i], 0xff)
+	}
+
+	if ok != 1 {
+		return ErrVerification
+	}
+
+	return nil
+}
+
+func pkcs1v15HashInfo(hash crypto.Hash, inLen int) (hashLen int, prefix []byte, err error) {
+	// Special case: crypto.Hash(0) is used to indicate that the data is
+	// signed directly.
+	if hash == 0 {
+		return inLen, nil, nil
+	}
+
+	hashLen = hash.Size()
+	if inLen != hashLen {
+		return 0, nil, errors.New("crypto/rsa: input must be hashed message")
+	}
+	prefix, ok := hashPrefixes[hash]
+	if !ok {
+		return 0, nil, errors.New("crypto/rsa: unsupported hash function")
+	}
+	return
+}
diff --git a/contrib/go/_std_1.19/src/crypto/rsa/pss.go b/contrib/go/_std_1.19/src/crypto/rsa/pss.go
new file mode 100644
index 0000000000..29e79bd342
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/rsa/pss.go
@@ -0,0 +1,338 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package rsa
+
+// This file implements the RSASSA-PSS signature scheme according to RFC 8017.
+
+import (
+	"bytes"
+	"crypto"
+	"crypto/internal/boring"
+	"errors"
+	"hash"
+	"io"
+	"math/big"
+)
+
+// Per RFC 8017, Section 9.1
+//
+//     EM = MGF1 xor DB || H( 8*0x00 || mHash || salt ) || 0xbc
+//
+// where
+//
+//     DB = PS || 0x01 || salt
+//
+// and PS can be empty so
+//
+//     emLen = dbLen + hLen + 1 = psLen + sLen + hLen + 2
+//
+
+func emsaPSSEncode(mHash []byte, emBits int, salt []byte, hash hash.Hash) ([]byte, error) {
+	// See RFC 8017, Section 9.1.1.
+
+	hLen := hash.Size()
+	sLen := len(salt)
+	emLen := (emBits + 7) / 8
+
+	// 1.  If the length of M is greater than the input limitation for the
+	//     hash function (2^61 - 1 octets for SHA-1), output "message too
+	//     long" and stop.
+	//
+	// 2.  Let mHash = Hash(M), an octet string of length hLen.
+
+	if len(mHash) != hLen {
+		return nil, errors.New("crypto/rsa: input must be hashed with given hash")
+	}
+
+	// 3.  If emLen < hLen + sLen + 2, output "encoding error" and stop.
+
+	if emLen < hLen+sLen+2 {
+		return nil, errors.New("crypto/rsa: key size too small for PSS signature")
+	}
+
+	em := make([]byte, emLen)
+	psLen := emLen - sLen - hLen - 2
+	db := em[:psLen+1+sLen]
+	h := em[psLen+1+sLen : emLen-1]
+
+	// 4.  Generate a random octet string salt of length sLen; if sLen = 0,
+	//     then salt is the empty string.
+	//
+	// 5.  Let
+	//       M' = (0x)00 00 00 00 00 00 00 00 || mHash || salt;
+	//
+	//     M' is an octet string of length 8 + hLen + sLen with eight
+	//     initial zero octets.
+	//
+	// 6.  Let H = Hash(M'), an octet string of length hLen.
+
+	var prefix [8]byte
+
+	hash.Write(prefix[:])
+	hash.Write(mHash)
+	hash.Write(salt)
+
+	h = hash.Sum(h[:0])
+	hash.Reset()
+
+	// 7.  Generate an octet string PS consisting of emLen - sLen - hLen - 2
+	//     zero octets. The length of PS may be 0.
+	//
+	// 8.  Let DB = PS || 0x01 || salt; DB is an octet string of length
+	//     emLen - hLen - 1.
+
+	db[psLen] = 0x01
+	copy(db[psLen+1:], salt)
+
+	// 9.  Let dbMask = MGF(H, emLen - hLen - 1).
+	//
+	// 10. Let maskedDB = DB \xor dbMask.
+
+	mgf1XOR(db, hash, h)
+
+	// 11. Set the leftmost 8 * emLen - emBits bits of the leftmost octet in
+	//     maskedDB to zero.
+
+	db[0] &= 0xff >> (8*emLen - emBits)
+
+	// 12. Let EM = maskedDB || H || 0xbc.
+	em[emLen-1] = 0xbc
+
+	// 13. Output EM.
+	return em, nil
+}
+
+func emsaPSSVerify(mHash, em []byte, emBits, sLen int, hash hash.Hash) error {
+	// See RFC 8017, Section 9.1.2.
+
+	hLen := hash.Size()
+	if sLen == PSSSaltLengthEqualsHash {
+		sLen = hLen
+	}
+	emLen := (emBits + 7) / 8
+	if emLen != len(em) {
+		return errors.New("rsa: internal error: inconsistent length")
+	}
+
+	// 1.  If the length of M is greater than the input limitation for the
+	//     hash function (2^61 - 1 octets for SHA-1), output "inconsistent"
+	//     and stop.
+	//
+	// 2.  Let mHash = Hash(M), an octet string of length hLen.
+	if hLen != len(mHash) {
+		return ErrVerification
+	}
+
+	// 3.  If emLen < hLen + sLen + 2, output "inconsistent" and stop.
+	if emLen < hLen+sLen+2 {
+		return ErrVerification
+	}
+
+	// 4.  If the rightmost octet of EM does not have hexadecimal value
+	//     0xbc, output "inconsistent" and stop.
+	if em[emLen-1] != 0xbc {
+		return ErrVerification
+	}
+
+	// 5.  Let maskedDB be the leftmost emLen - hLen - 1 octets of EM, and
+	//     let H be the next hLen octets.
+	db := em[:emLen-hLen-1]
+	h := em[emLen-hLen-1 : emLen-1]
+
+	// 6.  If the leftmost 8 * emLen - emBits bits of the leftmost octet in
+	//     maskedDB are not all equal to zero, output "inconsistent" and
+	//     stop.
+	var bitMask byte = 0xff >> (8*emLen - emBits)
+	if em[0] & ^bitMask != 0 {
+		return ErrVerification
+	}
+
+	// 7.  Let dbMask = MGF(H, emLen - hLen - 1).
+	//
+	// 8.  Let DB = maskedDB \xor dbMask.
+	mgf1XOR(db, hash, h)
+
+	// 9.  Set the leftmost 8 * emLen - emBits bits of the leftmost octet in DB
+	//     to zero.
+	db[0] &= bitMask
+
+	// If we don't know the salt length, look for the 0x01 delimiter.
+	if sLen == PSSSaltLengthAuto {
+		psLen := bytes.IndexByte(db, 0x01)
+		if psLen < 0 {
+			return ErrVerification
+		}
+		sLen = len(db) - psLen - 1
+	}
+
+	// 10. If the emLen - hLen - sLen - 2 leftmost octets of DB are not zero
+	//     or if the octet at position emLen - hLen - sLen - 1 (the leftmost
+	//     position is "position 1") does not have hexadecimal value 0x01,
+	//     output "inconsistent" and stop.
+	psLen := emLen - hLen - sLen - 2
+	for _, e := range db[:psLen] {
+		if e != 0x00 {
+			return ErrVerification
+		}
+	}
+	if db[psLen] != 0x01 {
+		return ErrVerification
+	}
+
+	// 11.  Let salt be the last sLen octets of DB.
+	salt := db[len(db)-sLen:]
+
+	// 12.  Let
+	//          M' = (0x)00 00 00 00 00 00 00 00 || mHash || salt ;
+	//     M' is an octet string of length 8 + hLen + sLen with eight
+	//     initial zero octets.
+	//
+	// 13. Let H' = Hash(M'), an octet string of length hLen.
+	var prefix [8]byte
+	hash.Write(prefix[:])
+	hash.Write(mHash)
+	hash.Write(salt)
+
+	h0 := hash.Sum(nil)
+
+	// 14. If H = H', output "consistent." Otherwise, output "inconsistent."
+	if !bytes.Equal(h0, h) { // TODO: constant time?
+		return ErrVerification
+	}
+	return nil
+}
+
+// signPSSWithSalt calculates the signature of hashed using PSS with specified salt.
+// Note that hashed must be the result of hashing the input message using the
+// given hash function. salt is a random sequence of bytes whose length will be
+// later used to verify the signature.
+func signPSSWithSalt(rand io.Reader, priv *PrivateKey, hash crypto.Hash, hashed, salt []byte) ([]byte, error) {
+	emBits := priv.N.BitLen() - 1
+	em, err := emsaPSSEncode(hashed, emBits, salt, hash.New())
+	if err != nil {
+		return nil, err
+	}
+
+	if boring.Enabled {
+		bkey, err := boringPrivateKey(priv)
+		if err != nil {
+			return nil, err
+		}
+		// Note: BoringCrypto takes care of the "AndCheck" part of "decryptAndCheck".
+		// (It's not just decrypt.)
+		s, err := boring.DecryptRSANoPadding(bkey, em)
+		if err != nil {
+			return nil, err
+		}
+		return s, nil
+	}
+
+	m := new(big.Int).SetBytes(em)
+	c, err := decryptAndCheck(rand, priv, m)
+	if err != nil {
+		return nil, err
+	}
+	s := make([]byte, priv.Size())
+	return c.FillBytes(s), nil
+}
+
+const (
+	// PSSSaltLengthAuto causes the salt in a PSS signature to be as large
+	// as possible when signing, and to be auto-detected when verifying.
+	PSSSaltLengthAuto = 0
+	// PSSSaltLengthEqualsHash causes the salt length to equal the length
+	// of the hash used in the signature.
+	PSSSaltLengthEqualsHash = -1
+)
+
+// PSSOptions contains options for creating and verifying PSS signatures.
+type PSSOptions struct {
+	// SaltLength controls the length of the salt used in the PSS
+	// signature. It can either be a number of bytes, or one of the special
+	// PSSSaltLength constants.
+	SaltLength int
+
+	// Hash is the hash function used to generate the message digest. If not
+	// zero, it overrides the hash function passed to SignPSS. It's required
+	// when using PrivateKey.Sign.
+	Hash crypto.Hash
+}
+
+// HashFunc returns opts.Hash so that PSSOptions implements crypto.SignerOpts.
+func (opts *PSSOptions) HashFunc() crypto.Hash {
+	return opts.Hash
+}
+
+func (opts *PSSOptions) saltLength() int {
+	if opts == nil {
+		return PSSSaltLengthAuto
+	}
+	return opts.SaltLength
+}
+
+// SignPSS calculates the signature of digest using PSS.
+//
+// digest must be the result of hashing the input message using the given hash
+// function. The opts argument may be nil, in which case sensible defaults are
+// used. If opts.Hash is set, it overrides hash.
+func SignPSS(rand io.Reader, priv *PrivateKey, hash crypto.Hash, digest []byte, opts *PSSOptions) ([]byte, error) {
+	if opts != nil && opts.Hash != 0 {
+		hash = opts.Hash
+	}
+
+	saltLength := opts.saltLength()
+	switch saltLength {
+	case PSSSaltLengthAuto:
+		saltLength = (priv.N.BitLen()-1+7)/8 - 2 - hash.Size()
+	case PSSSaltLengthEqualsHash:
+		saltLength = hash.Size()
+	}
+
+	if boring.Enabled && rand == boring.RandReader {
+		bkey, err := boringPrivateKey(priv)
+		if err != nil {
+			return nil, err
+		}
+		return boring.SignRSAPSS(bkey, hash, digest, saltLength)
+	}
+	boring.UnreachableExceptTests()
+
+	salt := make([]byte, saltLength)
+	if _, err := io.ReadFull(rand, salt); err != nil {
+		return nil, err
+	}
+	return signPSSWithSalt(rand, priv, hash, digest, salt)
+}
+
+// VerifyPSS verifies a PSS signature.
+//
+// A valid signature is indicated by returning a nil error. digest must be the
+// result of hashing the input message using the given hash function. The opts
+// argument may be nil, in which case sensible defaults are used. opts.Hash is
+// ignored.
+func VerifyPSS(pub *PublicKey, hash crypto.Hash, digest []byte, sig []byte, opts *PSSOptions) error {
+	if boring.Enabled {
+		bkey, err := boringPublicKey(pub)
+		if err != nil {
+			return err
+		}
+		if err := boring.VerifyRSAPSS(bkey, hash, digest, sig, opts.saltLength()); err != nil {
+			return ErrVerification
+		}
+		return nil
+	}
+	if len(sig) != pub.Size() {
+		return ErrVerification
+	}
+	s := new(big.Int).SetBytes(sig)
+	m := encrypt(new(big.Int), pub, s)
+	emBits := pub.N.BitLen() - 1
+	emLen := (emBits + 7) / 8
+	if m.BitLen() > emLen*8 {
+		return ErrVerification
+	}
+	em := m.FillBytes(make([]byte, emLen))
+	return emsaPSSVerify(digest, em, emBits, opts.saltLength(), hash.New())
+}
diff --git a/contrib/go/_std_1.19/src/crypto/rsa/rsa.go b/contrib/go/_std_1.19/src/crypto/rsa/rsa.go
new file mode 100644
index 0000000000..c941124fb2
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/rsa/rsa.go
@@ -0,0 +1,727 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package rsa implements RSA encryption as specified in PKCS #1 and RFC 8017.
+//
+// RSA is a single, fundamental operation that is used in this package to
+// implement either public-key encryption or public-key signatures.
+//
+// The original specification for encryption and signatures with RSA is PKCS #1
+// and the terms "RSA encryption" and "RSA signatures" by default refer to
+// PKCS #1 version 1.5. However, that specification has flaws and new designs
+// should use version 2, usually called by just OAEP and PSS, where
+// possible.
+//
+// Two sets of interfaces are included in this package. When a more abstract
+// interface isn't necessary, there are functions for encrypting/decrypting
+// with v1.5/OAEP and signing/verifying with v1.5/PSS. If one needs to abstract
+// over the public key primitive, the PrivateKey type implements the
+// Decrypter and Signer interfaces from the crypto package.
+//
+// The RSA operations in this package are not implemented using constant-time algorithms.
+package rsa
+
+import (
+	"crypto"
+	"crypto/internal/boring"
+	"crypto/internal/boring/bbig"
+	"crypto/internal/randutil"
+	"crypto/rand"
+	"crypto/subtle"
+	"errors"
+	"hash"
+	"io"
+	"math"
+	"math/big"
+)
+
+var bigZero = big.NewInt(0)
+var bigOne = big.NewInt(1)
+
+// A PublicKey represents the public part of an RSA key.
+type PublicKey struct {
+	N *big.Int // modulus
+	E int      // public exponent
+}
+
+// Any methods implemented on PublicKey might need to also be implemented on
+// PrivateKey, as the latter embeds the former and will expose its methods.
+
+// Size returns the modulus size in bytes. Raw signatures and ciphertexts
+// for or by this public key will have the same size.
+func (pub *PublicKey) Size() int {
+	return (pub.N.BitLen() + 7) / 8
+}
+
+// Equal reports whether pub and x have the same value.
+func (pub *PublicKey) Equal(x crypto.PublicKey) bool {
+	xx, ok := x.(*PublicKey)
+	if !ok {
+		return false
+	}
+	return pub.N.Cmp(xx.N) == 0 && pub.E == xx.E
+}
+
+// OAEPOptions is an interface for passing options to OAEP decryption using the
+// crypto.Decrypter interface.
+type OAEPOptions struct {
+	// Hash is the hash function that will be used when generating the mask.
+	Hash crypto.Hash
+	// Label is an arbitrary byte string that must be equal to the value
+	// used when encrypting.
+	Label []byte
+}
+
+var (
+	errPublicModulus       = errors.New("crypto/rsa: missing public modulus")
+	errPublicExponentSmall = errors.New("crypto/rsa: public exponent too small")
+	errPublicExponentLarge = errors.New("crypto/rsa: public exponent too large")
+)
+
+// checkPub sanity checks the public key before we use it.
+// We require pub.E to fit into a 32-bit integer so that we
+// do not have different behavior depending on whether
+// int is 32 or 64 bits. See also
+// https://www.imperialviolet.org/2012/03/16/rsae.html.
+func checkPub(pub *PublicKey) error {
+	if pub.N == nil {
+		return errPublicModulus
+	}
+	if pub.E < 2 {
+		return errPublicExponentSmall
+	}
+	if pub.E > 1<<31-1 {
+		return errPublicExponentLarge
+	}
+	return nil
+}
+
+// A PrivateKey represents an RSA key
+type PrivateKey struct {
+	PublicKey            // public part.
+	D         *big.Int   // private exponent
+	Primes    []*big.Int // prime factors of N, has >= 2 elements.
+
+	// Precomputed contains precomputed values that speed up private
+	// operations, if available.
+	Precomputed PrecomputedValues
+}
+
+// Public returns the public key corresponding to priv.
+func (priv *PrivateKey) Public() crypto.PublicKey {
+	return &priv.PublicKey
+}
+
+// Equal reports whether priv and x have equivalent values. It ignores
+// Precomputed values.
+func (priv *PrivateKey) Equal(x crypto.PrivateKey) bool {
+	xx, ok := x.(*PrivateKey)
+	if !ok {
+		return false
+	}
+	if !priv.PublicKey.Equal(&xx.PublicKey) || priv.D.Cmp(xx.D) != 0 {
+		return false
+	}
+	if len(priv.Primes) != len(xx.Primes) {
+		return false
+	}
+	for i := range priv.Primes {
+		if priv.Primes[i].Cmp(xx.Primes[i]) != 0 {
+			return false
+		}
+	}
+	return true
+}
+
+// Sign signs digest with priv, reading randomness from rand. If opts is a
+// *PSSOptions then the PSS algorithm will be used, otherwise PKCS #1 v1.5 will
+// be used. digest must be the result of hashing the input message using
+// opts.HashFunc().
+//
+// This method implements crypto.Signer, which is an interface to support keys
+// where the private part is kept in, for example, a hardware module. Common
+// uses should use the Sign* functions in this package directly.
+func (priv *PrivateKey) Sign(rand io.Reader, digest []byte, opts crypto.SignerOpts) ([]byte, error) {
+	if pssOpts, ok := opts.(*PSSOptions); ok {
+		return SignPSS(rand, priv, pssOpts.Hash, digest, pssOpts)
+	}
+
+	return SignPKCS1v15(rand, priv, opts.HashFunc(), digest)
+}
+
+// Decrypt decrypts ciphertext with priv. If opts is nil or of type
+// *PKCS1v15DecryptOptions then PKCS #1 v1.5 decryption is performed. Otherwise
+// opts must have type *OAEPOptions and OAEP decryption is done.
+func (priv *PrivateKey) Decrypt(rand io.Reader, ciphertext []byte, opts crypto.DecrypterOpts) (plaintext []byte, err error) {
+	if opts == nil {
+		return DecryptPKCS1v15(rand, priv, ciphertext)
+	}
+
+	switch opts := opts.(type) {
+	case *OAEPOptions:
+		return DecryptOAEP(opts.Hash.New(), rand, priv, ciphertext, opts.Label)
+
+	case *PKCS1v15DecryptOptions:
+		if l := opts.SessionKeyLen; l > 0 {
+			plaintext = make([]byte, l)
+			if _, err := io.ReadFull(rand, plaintext); err != nil {
+				return nil, err
+			}
+			if err := DecryptPKCS1v15SessionKey(rand, priv, ciphertext, plaintext); err != nil {
+				return nil, err
+			}
+			return plaintext, nil
+		} else {
+			return DecryptPKCS1v15(rand, priv, ciphertext)
+		}
+
+	default:
+		return nil, errors.New("crypto/rsa: invalid options for Decrypt")
+	}
+}
+
+type PrecomputedValues struct {
+	Dp, Dq *big.Int // D mod (P-1) (or mod Q-1)
+	Qinv   *big.Int // Q^-1 mod P
+
+	// CRTValues is used for the 3rd and subsequent primes. Due to a
+	// historical accident, the CRT for the first two primes is handled
+	// differently in PKCS #1 and interoperability is sufficiently
+	// important that we mirror this.
+	CRTValues []CRTValue
+}
+
+// CRTValue contains the precomputed Chinese remainder theorem values.
+type CRTValue struct {
+	Exp   *big.Int // D mod (prime-1).
+	Coeff *big.Int // R·Coeff ≡ 1 mod Prime.
+	R     *big.Int // product of primes prior to this (inc p and q).
+}
+
+// Validate performs basic sanity checks on the key.
+// It returns nil if the key is valid, or else an error describing a problem.
+func (priv *PrivateKey) Validate() error {
+	if err := checkPub(&priv.PublicKey); err != nil {
+		return err
+	}
+
+	// Check that Πprimes == n.
+	modulus := new(big.Int).Set(bigOne)
+	for _, prime := range priv.Primes {
+		// Any primes ≤ 1 will cause divide-by-zero panics later.
+		if prime.Cmp(bigOne) <= 0 {
+			return errors.New("crypto/rsa: invalid prime value")
+		}
+		modulus.Mul(modulus, prime)
+	}
+	if modulus.Cmp(priv.N) != 0 {
+		return errors.New("crypto/rsa: invalid modulus")
+	}
+
+	// Check that de ≡ 1 mod p-1, for each prime.
+	// This implies that e is coprime to each p-1 as e has a multiplicative
+	// inverse. Therefore e is coprime to lcm(p-1,q-1,r-1,...) =
+	// exponent(ℤ/nℤ). It also implies that a^de ≡ a mod p as a^(p-1) ≡ 1
+	// mod p. Thus a^de ≡ a mod n for all a coprime to n, as required.
+	congruence := new(big.Int)
+	de := new(big.Int).SetInt64(int64(priv.E))
+	de.Mul(de, priv.D)
+	for _, prime := range priv.Primes {
+		pminus1 := new(big.Int).Sub(prime, bigOne)
+		congruence.Mod(de, pminus1)
+		if congruence.Cmp(bigOne) != 0 {
+			return errors.New("crypto/rsa: invalid exponents")
+		}
+	}
+	return nil
+}
+
+// GenerateKey generates an RSA keypair of the given bit size using the
+// random source random (for example, crypto/rand.Reader).
+func GenerateKey(random io.Reader, bits int) (*PrivateKey, error) {
+	return GenerateMultiPrimeKey(random, 2, bits)
+}
+
+// GenerateMultiPrimeKey generates a multi-prime RSA keypair of the given bit
+// size and the given random source, as suggested in [1]. Although the public
+// keys are compatible (actually, indistinguishable) from the 2-prime case,
+// the private keys are not. Thus it may not be possible to export multi-prime
+// private keys in certain formats or to subsequently import them into other
+// code.
+//
+// Table 1 in [2] suggests maximum numbers of primes for a given size.
+//
+// [1] US patent 4405829 (1972, expired)
+// [2] http://www.cacr.math.uwaterloo.ca/techreports/2006/cacr2006-16.pdf
+func GenerateMultiPrimeKey(random io.Reader, nprimes int, bits int) (*PrivateKey, error) {
+	randutil.MaybeReadByte(random)
+
+	if boring.Enabled && random == boring.RandReader && nprimes == 2 && (bits == 2048 || bits == 3072) {
+		bN, bE, bD, bP, bQ, bDp, bDq, bQinv, err := boring.GenerateKeyRSA(bits)
+		if err != nil {
+			return nil, err
+		}
+		N := bbig.Dec(bN)
+		E := bbig.Dec(bE)
+		D := bbig.Dec(bD)
+		P := bbig.Dec(bP)
+		Q := bbig.Dec(bQ)
+		Dp := bbig.Dec(bDp)
+		Dq := bbig.Dec(bDq)
+		Qinv := bbig.Dec(bQinv)
+		e64 := E.Int64()
+		if !E.IsInt64() || int64(int(e64)) != e64 {
+			return nil, errors.New("crypto/rsa: generated key exponent too large")
+		}
+		key := &PrivateKey{
+			PublicKey: PublicKey{
+				N: N,
+				E: int(e64),
+			},
+			D:      D,
+			Primes: []*big.Int{P, Q},
+			Precomputed: PrecomputedValues{
+				Dp:        Dp,
+				Dq:        Dq,
+				Qinv:      Qinv,
+				CRTValues: make([]CRTValue, 0), // non-nil, to match Precompute
+			},
+		}
+		return key, nil
+	}
+
+	priv := new(PrivateKey)
+	priv.E = 65537
+
+	if nprimes < 2 {
+		return nil, errors.New("crypto/rsa: GenerateMultiPrimeKey: nprimes must be >= 2")
+	}
+
+	if bits < 64 {
+		primeLimit := float64(uint64(1) << uint(bits/nprimes))
+		// pi approximates the number of primes less than primeLimit
+		pi := primeLimit / (math.Log(primeLimit) - 1)
+		// Generated primes start with 11 (in binary) so we can only
+		// use a quarter of them.
+		pi /= 4
+		// Use a factor of two to ensure that key generation terminates
+		// in a reasonable amount of time.
+		pi /= 2
+		if pi <= float64(nprimes) {
+			return nil, errors.New("crypto/rsa: too few primes of given length to generate an RSA key")
+		}
+	}
+
+	primes := make([]*big.Int, nprimes)
+
+NextSetOfPrimes:
+	for {
+		todo := bits
+		// crypto/rand should set the top two bits in each prime.
+		// Thus each prime has the form
+		//   p_i = 2^bitlen(p_i) × 0.11... (in base 2).
+		// And the product is:
+		//   P = 2^todo × α
+		// where α is the product of nprimes numbers of the form 0.11...
+		//
+		// If α < 1/2 (which can happen for nprimes > 2), we need to
+		// shift todo to compensate for lost bits: the mean value of 0.11...
+		// is 7/8, so todo + shift - nprimes * log2(7/8) ~= bits - 1/2
+		// will give good results.
+		if nprimes >= 7 {
+			todo += (nprimes - 2) / 5
+		}
+		for i := 0; i < nprimes; i++ {
+			var err error
+			primes[i], err = rand.Prime(random, todo/(nprimes-i))
+			if err != nil {
+				return nil, err
+			}
+			todo -= primes[i].BitLen()
+		}
+
+		// Make sure that primes is pairwise unequal.
+		for i, prime := range primes {
+			for j := 0; j < i; j++ {
+				if prime.Cmp(primes[j]) == 0 {
+					continue NextSetOfPrimes
+				}
+			}
+		}
+
+		n := new(big.Int).Set(bigOne)
+		totient := new(big.Int).Set(bigOne)
+		pminus1 := new(big.Int)
+		for _, prime := range primes {
+			n.Mul(n, prime)
+			pminus1.Sub(prime, bigOne)
+			totient.Mul(totient, pminus1)
+		}
+		if n.BitLen() != bits {
+			// This should never happen for nprimes == 2 because
+			// crypto/rand should set the top two bits in each prime.
+			// For nprimes > 2 we hope it does not happen often.
+			continue NextSetOfPrimes
+		}
+
+		priv.D = new(big.Int)
+		e := big.NewInt(int64(priv.E))
+		ok := priv.D.ModInverse(e, totient)
+
+		if ok != nil {
+			priv.Primes = primes
+			priv.N = n
+			break
+		}
+	}
+
+	priv.Precompute()
+	return priv, nil
+}
+
+// incCounter increments a four byte, big-endian counter.
+func incCounter(c *[4]byte) {
+	if c[3]++; c[3] != 0 {
+		return
+	}
+	if c[2]++; c[2] != 0 {
+		return
+	}
+	if c[1]++; c[1] != 0 {
+		return
+	}
+	c[0]++
+}
+
+// mgf1XOR XORs the bytes in out with a mask generated using the MGF1 function
+// specified in PKCS #1 v2.1.
+func mgf1XOR(out []byte, hash hash.Hash, seed []byte) {
+	var counter [4]byte
+	var digest []byte
+
+	done := 0
+	for done < len(out) {
+		hash.Write(seed)
+		hash.Write(counter[0:4])
+		digest = hash.Sum(digest[:0])
+		hash.Reset()
+
+		for i := 0; i < len(digest) && done < len(out); i++ {
+			out[done] ^= digest[i]
+			done++
+		}
+		incCounter(&counter)
+	}
+}
+
+// ErrMessageTooLong is returned when attempting to encrypt a message which is
+// too large for the size of the public key.
+var ErrMessageTooLong = errors.New("crypto/rsa: message too long for RSA public key size")
+
+func encrypt(c *big.Int, pub *PublicKey, m *big.Int) *big.Int {
+	boring.Unreachable()
+	e := big.NewInt(int64(pub.E))
+	c.Exp(m, e, pub.N)
+	return c
+}
+
+// EncryptOAEP encrypts the given message with RSA-OAEP.
+//
+// OAEP is parameterised by a hash function that is used as a random oracle.
+// Encryption and decryption of a given message must use the same hash function
+// and sha256.New() is a reasonable choice.
+//
+// The random parameter is used as a source of entropy to ensure that
+// encrypting the same message twice doesn't result in the same ciphertext.
+//
+// The label parameter may contain arbitrary data that will not be encrypted,
+// but which gives important context to the message. For example, if a given
+// public key is used to encrypt two types of messages then distinct label
+// values could be used to ensure that a ciphertext for one purpose cannot be
+// used for another by an attacker. If not required it can be empty.
+//
+// The message must be no longer than the length of the public modulus minus
+// twice the hash length, minus a further 2.
+func EncryptOAEP(hash hash.Hash, random io.Reader, pub *PublicKey, msg []byte, label []byte) ([]byte, error) {
+	if err := checkPub(pub); err != nil {
+		return nil, err
+	}
+	hash.Reset()
+	k := pub.Size()
+	if len(msg) > k-2*hash.Size()-2 {
+		return nil, ErrMessageTooLong
+	}
+
+	if boring.Enabled && random == boring.RandReader {
+		bkey, err := boringPublicKey(pub)
+		if err != nil {
+			return nil, err
+		}
+		return boring.EncryptRSAOAEP(hash, bkey, msg, label)
+	}
+	boring.UnreachableExceptTests()
+
+	hash.Write(label)
+	lHash := hash.Sum(nil)
+	hash.Reset()
+
+	em := make([]byte, k)
+	seed := em[1 : 1+hash.Size()]
+	db := em[1+hash.Size():]
+
+	copy(db[0:hash.Size()], lHash)
+	db[len(db)-len(msg)-1] = 1
+	copy(db[len(db)-len(msg):], msg)
+
+	_, err := io.ReadFull(random, seed)
+	if err != nil {
+		return nil, err
+	}
+
+	mgf1XOR(db, hash, seed)
+	mgf1XOR(seed, hash, db)
+
+	if boring.Enabled {
+		var bkey *boring.PublicKeyRSA
+		bkey, err = boringPublicKey(pub)
+		if err != nil {
+			return nil, err
+		}
+		return boring.EncryptRSANoPadding(bkey, em)
+	}
+
+	m := new(big.Int)
+	m.SetBytes(em)
+	c := encrypt(new(big.Int), pub, m)
+
+	out := make([]byte, k)
+	return c.FillBytes(out), nil
+}
+
+// ErrDecryption represents a failure to decrypt a message.
+// It is deliberately vague to avoid adaptive attacks.
+var ErrDecryption = errors.New("crypto/rsa: decryption error")
+
+// ErrVerification represents a failure to verify a signature.
+// It is deliberately vague to avoid adaptive attacks.
+var ErrVerification = errors.New("crypto/rsa: verification error")
+
+// Precompute performs some calculations that speed up private key operations
+// in the future.
+func (priv *PrivateKey) Precompute() {
+	if priv.Precomputed.Dp != nil {
+		return
+	}
+
+	priv.Precomputed.Dp = new(big.Int).Sub(priv.Primes[0], bigOne)
+	priv.Precomputed.Dp.Mod(priv.D, priv.Precomputed.Dp)
+
+	priv.Precomputed.Dq = new(big.Int).Sub(priv.Primes[1], bigOne)
+	priv.Precomputed.Dq.Mod(priv.D, priv.Precomputed.Dq)
+
+	priv.Precomputed.Qinv = new(big.Int).ModInverse(priv.Primes[1], priv.Primes[0])
+
+	r := new(big.Int).Mul(priv.Primes[0], priv.Primes[1])
+	priv.Precomputed.CRTValues = make([]CRTValue, len(priv.Primes)-2)
+	for i := 2; i < len(priv.Primes); i++ {
+		prime := priv.Primes[i]
+		values := &priv.Precomputed.CRTValues[i-2]
+
+		values.Exp = new(big.Int).Sub(prime, bigOne)
+		values.Exp.Mod(priv.D, values.Exp)
+
+		values.R = new(big.Int).Set(r)
+		values.Coeff = new(big.Int).ModInverse(r, prime)
+
+		r.Mul(r, prime)
+	}
+}
+
+// decrypt performs an RSA decryption, resulting in a plaintext integer. If a
+// random source is given, RSA blinding is used.
+func decrypt(random io.Reader, priv *PrivateKey, c *big.Int) (m *big.Int, err error) {
+	if len(priv.Primes) <= 2 {
+		boring.Unreachable()
+	}
+	// TODO(agl): can we get away with reusing blinds?
+	if c.Cmp(priv.N) > 0 {
+		err = ErrDecryption
+		return
+	}
+	if priv.N.Sign() == 0 {
+		return nil, ErrDecryption
+	}
+
+	var ir *big.Int
+	if random != nil {
+		randutil.MaybeReadByte(random)
+
+		// Blinding enabled. Blinding involves multiplying c by r^e.
+		// Then the decryption operation performs (m^e * r^e)^d mod n
+		// which equals mr mod n. The factor of r can then be removed
+		// by multiplying by the multiplicative inverse of r.
+
+		var r *big.Int
+		ir = new(big.Int)
+		for {
+			r, err = rand.Int(random, priv.N)
+			if err != nil {
+				return
+			}
+			if r.Cmp(bigZero) == 0 {
+				r = bigOne
+			}
+			ok := ir.ModInverse(r, priv.N)
+			if ok != nil {
+				break
+			}
+		}
+		bigE := big.NewInt(int64(priv.E))
+		rpowe := new(big.Int).Exp(r, bigE, priv.N) // N != 0
+		cCopy := new(big.Int).Set(c)
+		cCopy.Mul(cCopy, rpowe)
+		cCopy.Mod(cCopy, priv.N)
+		c = cCopy
+	}
+
+	if priv.Precomputed.Dp == nil {
+		m = new(big.Int).Exp(c, priv.D, priv.N)
+	} else {
+		// We have the precalculated values needed for the CRT.
+		m = new(big.Int).Exp(c, priv.Precomputed.Dp, priv.Primes[0])
+		m2 := new(big.Int).Exp(c, priv.Precomputed.Dq, priv.Primes[1])
+		m.Sub(m, m2)
+		if m.Sign() < 0 {
+			m.Add(m, priv.Primes[0])
+		}
+		m.Mul(m, priv.Precomputed.Qinv)
+		m.Mod(m, priv.Primes[0])
+		m.Mul(m, priv.Primes[1])
+		m.Add(m, m2)
+
+		for i, values := range priv.Precomputed.CRTValues {
+			prime := priv.Primes[2+i]
+			m2.Exp(c, values.Exp, prime)
+			m2.Sub(m2, m)
+			m2.Mul(m2, values.Coeff)
+			m2.Mod(m2, prime)
+			if m2.Sign() < 0 {
+				m2.Add(m2, prime)
+			}
+			m2.Mul(m2, values.R)
+			m.Add(m, m2)
+		}
+	}
+
+	if ir != nil {
+		// Unblind.
+		m.Mul(m, ir)
+		m.Mod(m, priv.N)
+	}
+
+	return
+}
+
+func decryptAndCheck(random io.Reader, priv *PrivateKey, c *big.Int) (m *big.Int, err error) {
+	m, err = decrypt(random, priv, c)
+	if err != nil {
+		return nil, err
+	}
+
+	// In order to defend against errors in the CRT computation, m^e is
+	// calculated, which should match the original ciphertext.
+	check := encrypt(new(big.Int), &priv.PublicKey, m)
+	if c.Cmp(check) != 0 {
+		return nil, errors.New("rsa: internal error")
+	}
+	return m, nil
+}
+
+// DecryptOAEP decrypts ciphertext using RSA-OAEP.
+//
+// OAEP is parameterised by a hash function that is used as a random oracle.
+// Encryption and decryption of a given message must use the same hash function
+// and sha256.New() is a reasonable choice.
+//
+// The random parameter, if not nil, is used to blind the private-key operation
+// and avoid timing side-channel attacks. Blinding is purely internal to this
+// function – the random data need not match that used when encrypting.
+//
+// The label parameter must match the value given when encrypting. See
+// EncryptOAEP for details.
+func DecryptOAEP(hash hash.Hash, random io.Reader, priv *PrivateKey, ciphertext []byte, label []byte) ([]byte, error) {
+	if err := checkPub(&priv.PublicKey); err != nil {
+		return nil, err
+	}
+	k := priv.Size()
+	if len(ciphertext) > k ||
+		k < hash.Size()*2+2 {
+		return nil, ErrDecryption
+	}
+
+	if boring.Enabled {
+		bkey, err := boringPrivateKey(priv)
+		if err != nil {
+			return nil, err
+		}
+		out, err := boring.DecryptRSAOAEP(hash, bkey, ciphertext, label)
+		if err != nil {
+			return nil, ErrDecryption
+		}
+		return out, nil
+	}
+	c := new(big.Int).SetBytes(ciphertext)
+
+	m, err := decrypt(random, priv, c)
+	if err != nil {
+		return nil, err
+	}
+
+	hash.Write(label)
+	lHash := hash.Sum(nil)
+	hash.Reset()
+
+	// We probably leak the number of leading zeros.
+	// It's not clear that we can do anything about this.
+	em := m.FillBytes(make([]byte, k))
+
+	firstByteIsZero := subtle.ConstantTimeByteEq(em[0], 0)
+
+	seed := em[1 : hash.Size()+1]
+	db := em[hash.Size()+1:]
+
+	mgf1XOR(seed, hash, db)
+	mgf1XOR(db, hash, seed)
+
+	lHash2 := db[0:hash.Size()]
+
+	// We have to validate the plaintext in constant time in order to avoid
+	// attacks like: J. Manger. A Chosen Ciphertext Attack on RSA Optimal
+	// Asymmetric Encryption Padding (OAEP) as Standardized in PKCS #1
+	// v2.0. In J. Kilian, editor, Advances in Cryptology.
+	lHash2Good := subtle.ConstantTimeCompare(lHash, lHash2)
+
+	// The remainder of the plaintext must be zero or more 0x00, followed
+	// by 0x01, followed by the message.
+	//   lookingForIndex: 1 iff we are still looking for the 0x01
+	//   index: the offset of the first 0x01 byte
+	//   invalid: 1 iff we saw a non-zero byte before the 0x01.
+	var lookingForIndex, index, invalid int
+	lookingForIndex = 1
+	rest := db[hash.Size():]
+
+	for i := 0; i < len(rest); i++ {
+		equals0 := subtle.ConstantTimeByteEq(rest[i], 0)
+		equals1 := subtle.ConstantTimeByteEq(rest[i], 1)
+		index = subtle.ConstantTimeSelect(lookingForIndex&equals1, i, index)
+		lookingForIndex = subtle.ConstantTimeSelect(equals1, 0, lookingForIndex)
+		invalid = subtle.ConstantTimeSelect(lookingForIndex&^equals0, 1, invalid)
+	}
+
+	if firstByteIsZero&lHash2Good&^invalid&^lookingForIndex != 1 {
+		return nil, ErrDecryption
+	}
+
+	return rest[index+1:], nil
+}
diff --git a/contrib/go/_std_1.19/src/crypto/sha1/boring.go b/contrib/go/_std_1.19/src/crypto/sha1/boring.go
new file mode 100644
index 0000000000..b5786d1bf4
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/sha1/boring.go
@@ -0,0 +1,25 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Extra indirection here so that when building go_bootstrap
+// cmd/internal/boring is not even imported, so that we don't
+// have to maintain changes to cmd/dist's deps graph.
+
+//go:build !cmd_go_bootstrap && cgo
+// +build !cmd_go_bootstrap,cgo
+
+package sha1
+
+import (
+	"crypto/internal/boring"
+	"hash"
+)
+
+const boringEnabled = boring.Enabled
+
+func boringNewSHA1() hash.Hash { return boring.NewSHA1() }
+
+func boringUnreachable() { boring.Unreachable() }
+
+func boringSHA1(p []byte) [20]byte { return boring.SHA1(p) }
diff --git a/contrib/go/_std_1.19/src/crypto/sha1/sha1.go b/contrib/go/_std_1.19/src/crypto/sha1/sha1.go
new file mode 100644
index 0000000000..271852d21b
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/sha1/sha1.go
@@ -0,0 +1,274 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package sha1 implements the SHA-1 hash algorithm as defined in RFC 3174.
+//
+// SHA-1 is cryptographically broken and should not be used for secure
+// applications.
+package sha1
+
+import (
+	"crypto"
+	"encoding/binary"
+	"errors"
+	"hash"
+)
+
+func init() {
+	crypto.RegisterHash(crypto.SHA1, New)
+}
+
+// The size of a SHA-1 checksum in bytes.
+const Size = 20
+
+// The blocksize of SHA-1 in bytes.
+const BlockSize = 64
+
+const (
+	chunk = 64
+	init0 = 0x67452301
+	init1 = 0xEFCDAB89
+	init2 = 0x98BADCFE
+	init3 = 0x10325476
+	init4 = 0xC3D2E1F0
+)
+
+// digest represents the partial evaluation of a checksum.
+type digest struct {
+	h   [5]uint32
+	x   [chunk]byte
+	nx  int
+	len uint64
+}
+
+const (
+	magic         = "sha\x01"
+	marshaledSize = len(magic) + 5*4 + chunk + 8
+)
+
+func (d *digest) MarshalBinary() ([]byte, error) {
+	b := make([]byte, 0, marshaledSize)
+	b = append(b, magic...)
+	b = appendUint32(b, d.h[0])
+	b = appendUint32(b, d.h[1])
+	b = appendUint32(b, d.h[2])
+	b = appendUint32(b, d.h[3])
+	b = appendUint32(b, d.h[4])
+	b = append(b, d.x[:d.nx]...)
+	b = b[:len(b)+len(d.x)-int(d.nx)] // already zero
+	b = appendUint64(b, d.len)
+	return b, nil
+}
+
+func (d *digest) UnmarshalBinary(b []byte) error {
+	if len(b) < len(magic) || string(b[:len(magic)]) != magic {
+		return errors.New("crypto/sha1: invalid hash state identifier")
+	}
+	if len(b) != marshaledSize {
+		return errors.New("crypto/sha1: invalid hash state size")
+	}
+	b = b[len(magic):]
+	b, d.h[0] = consumeUint32(b)
+	b, d.h[1] = consumeUint32(b)
+	b, d.h[2] = consumeUint32(b)
+	b, d.h[3] = consumeUint32(b)
+	b, d.h[4] = consumeUint32(b)
+	b = b[copy(d.x[:], b):]
+	b, d.len = consumeUint64(b)
+	d.nx = int(d.len % chunk)
+	return nil
+}
+
+func appendUint64(b []byte, x uint64) []byte {
+	var a [8]byte
+	binary.BigEndian.PutUint64(a[:], x)
+	return append(b, a[:]...)
+}
+
+func appendUint32(b []byte, x uint32) []byte {
+	var a [4]byte
+	binary.BigEndian.PutUint32(a[:], x)
+	return append(b, a[:]...)
+}
+
+func consumeUint64(b []byte) ([]byte, uint64) {
+	_ = b[7]
+	x := uint64(b[7]) | uint64(b[6])<<8 | uint64(b[5])<<16 | uint64(b[4])<<24 |
+		uint64(b[3])<<32 | uint64(b[2])<<40 | uint64(b[1])<<48 | uint64(b[0])<<56
+	return b[8:], x
+}
+
+func consumeUint32(b []byte) ([]byte, uint32) {
+	_ = b[3]
+	x := uint32(b[3]) | uint32(b[2])<<8 | uint32(b[1])<<16 | uint32(b[0])<<24
+	return b[4:], x
+}
+
+func (d *digest) Reset() {
+	d.h[0] = init0
+	d.h[1] = init1
+	d.h[2] = init2
+	d.h[3] = init3
+	d.h[4] = init4
+	d.nx = 0
+	d.len = 0
+}
+
+// New returns a new hash.Hash computing the SHA1 checksum. The Hash also
+// implements encoding.BinaryMarshaler and encoding.BinaryUnmarshaler to
+// marshal and unmarshal the internal state of the hash.
+func New() hash.Hash {
+	if boringEnabled {
+		return boringNewSHA1()
+	}
+	d := new(digest)
+	d.Reset()
+	return d
+}
+
+func (d *digest) Size() int { return Size }
+
+func (d *digest) BlockSize() int { return BlockSize }
+
+func (d *digest) Write(p []byte) (nn int, err error) {
+	boringUnreachable()
+	nn = len(p)
+	d.len += uint64(nn)
+	if d.nx > 0 {
+		n := copy(d.x[d.nx:], p)
+		d.nx += n
+		if d.nx == chunk {
+			block(d, d.x[:])
+			d.nx = 0
+		}
+		p = p[n:]
+	}
+	if len(p) >= chunk {
+		n := len(p) &^ (chunk - 1)
+		block(d, p[:n])
+		p = p[n:]
+	}
+	if len(p) > 0 {
+		d.nx = copy(d.x[:], p)
+	}
+	return
+}
+
+func (d *digest) Sum(in []byte) []byte {
+	boringUnreachable()
+	// Make a copy of d so that caller can keep writing and summing.
+	d0 := *d
+	hash := d0.checkSum()
+	return append(in, hash[:]...)
+}
+
+func (d *digest) checkSum() [Size]byte {
+	len := d.len
+	// Padding.  Add a 1 bit and 0 bits until 56 bytes mod 64.
+	var tmp [64]byte
+	tmp[0] = 0x80
+	if len%64 < 56 {
+		d.Write(tmp[0 : 56-len%64])
+	} else {
+		d.Write(tmp[0 : 64+56-len%64])
+	}
+
+	// Length in bits.
+	len <<= 3
+	binary.BigEndian.PutUint64(tmp[:], len)
+	d.Write(tmp[0:8])
+
+	if d.nx != 0 {
+		panic("d.nx != 0")
+	}
+
+	var digest [Size]byte
+
+	binary.BigEndian.PutUint32(digest[0:], d.h[0])
+	binary.BigEndian.PutUint32(digest[4:], d.h[1])
+	binary.BigEndian.PutUint32(digest[8:], d.h[2])
+	binary.BigEndian.PutUint32(digest[12:], d.h[3])
+	binary.BigEndian.PutUint32(digest[16:], d.h[4])
+
+	return digest
+}
+
+// ConstantTimeSum computes the same result of Sum() but in constant time
+func (d *digest) ConstantTimeSum(in []byte) []byte {
+	d0 := *d
+	hash := d0.constSum()
+	return append(in, hash[:]...)
+}
+
+func (d *digest) constSum() [Size]byte {
+	var length [8]byte
+	l := d.len << 3
+	for i := uint(0); i < 8; i++ {
+		length[i] = byte(l >> (56 - 8*i))
+	}
+
+	nx := byte(d.nx)
+	t := nx - 56                 // if nx < 56 then the MSB of t is one
+	mask1b := byte(int8(t) >> 7) // mask1b is 0xFF iff one block is enough
+
+	separator := byte(0x80) // gets reset to 0x00 once used
+	for i := byte(0); i < chunk; i++ {
+		mask := byte(int8(i-nx) >> 7) // 0x00 after the end of data
+
+		// if we reached the end of the data, replace with 0x80 or 0x00
+		d.x[i] = (^mask & separator) | (mask & d.x[i])
+
+		// zero the separator once used
+		separator &= mask
+
+		if i >= 56 {
+			// we might have to write the length here if all fit in one block
+			d.x[i] |= mask1b & length[i-56]
+		}
+	}
+
+	// compress, and only keep the digest if all fit in one block
+	block(d, d.x[:])
+
+	var digest [Size]byte
+	for i, s := range d.h {
+		digest[i*4] = mask1b & byte(s>>24)
+		digest[i*4+1] = mask1b & byte(s>>16)
+		digest[i*4+2] = mask1b & byte(s>>8)
+		digest[i*4+3] = mask1b & byte(s)
+	}
+
+	for i := byte(0); i < chunk; i++ {
+		// second block, it's always past the end of data, might start with 0x80
+		if i < 56 {
+			d.x[i] = separator
+			separator = 0
+		} else {
+			d.x[i] = length[i-56]
+		}
+	}
+
+	// compress, and only keep the digest if we actually needed the second block
+	block(d, d.x[:])
+
+	for i, s := range d.h {
+		digest[i*4] |= ^mask1b & byte(s>>24)
+		digest[i*4+1] |= ^mask1b & byte(s>>16)
+		digest[i*4+2] |= ^mask1b & byte(s>>8)
+		digest[i*4+3] |= ^mask1b & byte(s)
+	}
+
+	return digest
+}
+
+// Sum returns the SHA-1 checksum of the data.
+func Sum(data []byte) [Size]byte {
+	if boringEnabled {
+		return boringSHA1(data)
+	}
+	var d digest
+	d.Reset()
+	d.Write(data)
+	return d.checkSum()
+}
diff --git a/contrib/go/_std_1.18/src/crypto/sha1/sha1block.go b/contrib/go/_std_1.19/src/crypto/sha1/sha1block.go
index 321d34351c..321d34351c 100644
--- a/contrib/go/_std_1.18/src/crypto/sha1/sha1block.go
+++ b/contrib/go/_std_1.19/src/crypto/sha1/sha1block.go
diff --git a/contrib/go/_std_1.18/src/crypto/sha1/sha1block_amd64.go b/contrib/go/_std_1.19/src/crypto/sha1/sha1block_amd64.go
index 039813d7dc..039813d7dc 100644
--- a/contrib/go/_std_1.18/src/crypto/sha1/sha1block_amd64.go
+++ b/contrib/go/_std_1.19/src/crypto/sha1/sha1block_amd64.go
diff --git a/contrib/go/_std_1.18/src/crypto/sha1/sha1block_amd64.s b/contrib/go/_std_1.19/src/crypto/sha1/sha1block_amd64.s
index 42f03fb268..42f03fb268 100644
--- a/contrib/go/_std_1.18/src/crypto/sha1/sha1block_amd64.s
+++ b/contrib/go/_std_1.19/src/crypto/sha1/sha1block_amd64.s
diff --git a/contrib/go/_std_1.19/src/crypto/sha256/sha256.go b/contrib/go/_std_1.19/src/crypto/sha256/sha256.go
new file mode 100644
index 0000000000..e3c15e66ca
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/sha256/sha256.go
@@ -0,0 +1,285 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package sha256 implements the SHA224 and SHA256 hash algorithms as defined
+// in FIPS 180-4.
+package sha256
+
+import (
+	"crypto"
+	"crypto/internal/boring"
+	"encoding/binary"
+	"errors"
+	"hash"
+)
+
+func init() {
+	crypto.RegisterHash(crypto.SHA224, New224)
+	crypto.RegisterHash(crypto.SHA256, New)
+}
+
+// The size of a SHA256 checksum in bytes.
+const Size = 32
+
+// The size of a SHA224 checksum in bytes.
+const Size224 = 28
+
+// The blocksize of SHA256 and SHA224 in bytes.
+const BlockSize = 64
+
+const (
+	chunk     = 64
+	init0     = 0x6A09E667
+	init1     = 0xBB67AE85
+	init2     = 0x3C6EF372
+	init3     = 0xA54FF53A
+	init4     = 0x510E527F
+	init5     = 0x9B05688C
+	init6     = 0x1F83D9AB
+	init7     = 0x5BE0CD19
+	init0_224 = 0xC1059ED8
+	init1_224 = 0x367CD507
+	init2_224 = 0x3070DD17
+	init3_224 = 0xF70E5939
+	init4_224 = 0xFFC00B31
+	init5_224 = 0x68581511
+	init6_224 = 0x64F98FA7
+	init7_224 = 0xBEFA4FA4
+)
+
+// digest represents the partial evaluation of a checksum.
+type digest struct {
+	h     [8]uint32
+	x     [chunk]byte
+	nx    int
+	len   uint64
+	is224 bool // mark if this digest is SHA-224
+}
+
+const (
+	magic224      = "sha\x02"
+	magic256      = "sha\x03"
+	marshaledSize = len(magic256) + 8*4 + chunk + 8
+)
+
+func (d *digest) MarshalBinary() ([]byte, error) {
+	b := make([]byte, 0, marshaledSize)
+	if d.is224 {
+		b = append(b, magic224...)
+	} else {
+		b = append(b, magic256...)
+	}
+	b = appendUint32(b, d.h[0])
+	b = appendUint32(b, d.h[1])
+	b = appendUint32(b, d.h[2])
+	b = appendUint32(b, d.h[3])
+	b = appendUint32(b, d.h[4])
+	b = appendUint32(b, d.h[5])
+	b = appendUint32(b, d.h[6])
+	b = appendUint32(b, d.h[7])
+	b = append(b, d.x[:d.nx]...)
+	b = b[:len(b)+len(d.x)-int(d.nx)] // already zero
+	b = appendUint64(b, d.len)
+	return b, nil
+}
+
+func (d *digest) UnmarshalBinary(b []byte) error {
+	if len(b) < len(magic224) || (d.is224 && string(b[:len(magic224)]) != magic224) || (!d.is224 && string(b[:len(magic256)]) != magic256) {
+		return errors.New("crypto/sha256: invalid hash state identifier")
+	}
+	if len(b) != marshaledSize {
+		return errors.New("crypto/sha256: invalid hash state size")
+	}
+	b = b[len(magic224):]
+	b, d.h[0] = consumeUint32(b)
+	b, d.h[1] = consumeUint32(b)
+	b, d.h[2] = consumeUint32(b)
+	b, d.h[3] = consumeUint32(b)
+	b, d.h[4] = consumeUint32(b)
+	b, d.h[5] = consumeUint32(b)
+	b, d.h[6] = consumeUint32(b)
+	b, d.h[7] = consumeUint32(b)
+	b = b[copy(d.x[:], b):]
+	b, d.len = consumeUint64(b)
+	d.nx = int(d.len % chunk)
+	return nil
+}
+
+func appendUint64(b []byte, x uint64) []byte {
+	var a [8]byte
+	binary.BigEndian.PutUint64(a[:], x)
+	return append(b, a[:]...)
+}
+
+func appendUint32(b []byte, x uint32) []byte {
+	var a [4]byte
+	binary.BigEndian.PutUint32(a[:], x)
+	return append(b, a[:]...)
+}
+
+func consumeUint64(b []byte) ([]byte, uint64) {
+	_ = b[7]
+	x := uint64(b[7]) | uint64(b[6])<<8 | uint64(b[5])<<16 | uint64(b[4])<<24 |
+		uint64(b[3])<<32 | uint64(b[2])<<40 | uint64(b[1])<<48 | uint64(b[0])<<56
+	return b[8:], x
+}
+
+func consumeUint32(b []byte) ([]byte, uint32) {
+	_ = b[3]
+	x := uint32(b[3]) | uint32(b[2])<<8 | uint32(b[1])<<16 | uint32(b[0])<<24
+	return b[4:], x
+}
+
+func (d *digest) Reset() {
+	if !d.is224 {
+		d.h[0] = init0
+		d.h[1] = init1
+		d.h[2] = init2
+		d.h[3] = init3
+		d.h[4] = init4
+		d.h[5] = init5
+		d.h[6] = init6
+		d.h[7] = init7
+	} else {
+		d.h[0] = init0_224
+		d.h[1] = init1_224
+		d.h[2] = init2_224
+		d.h[3] = init3_224
+		d.h[4] = init4_224
+		d.h[5] = init5_224
+		d.h[6] = init6_224
+		d.h[7] = init7_224
+	}
+	d.nx = 0
+	d.len = 0
+}
+
+// New returns a new hash.Hash computing the SHA256 checksum. The Hash
+// also implements encoding.BinaryMarshaler and
+// encoding.BinaryUnmarshaler to marshal and unmarshal the internal
+// state of the hash.
+func New() hash.Hash {
+	if boring.Enabled {
+		return boring.NewSHA256()
+	}
+	d := new(digest)
+	d.Reset()
+	return d
+}
+
+// New224 returns a new hash.Hash computing the SHA224 checksum.
+func New224() hash.Hash {
+	if boring.Enabled {
+		return boring.NewSHA224()
+	}
+	d := new(digest)
+	d.is224 = true
+	d.Reset()
+	return d
+}
+
+func (d *digest) Size() int {
+	if !d.is224 {
+		return Size
+	}
+	return Size224
+}
+
+func (d *digest) BlockSize() int { return BlockSize }
+
+func (d *digest) Write(p []byte) (nn int, err error) {
+	boring.Unreachable()
+	nn = len(p)
+	d.len += uint64(nn)
+	if d.nx > 0 {
+		n := copy(d.x[d.nx:], p)
+		d.nx += n
+		if d.nx == chunk {
+			block(d, d.x[:])
+			d.nx = 0
+		}
+		p = p[n:]
+	}
+	if len(p) >= chunk {
+		n := len(p) &^ (chunk - 1)
+		block(d, p[:n])
+		p = p[n:]
+	}
+	if len(p) > 0 {
+		d.nx = copy(d.x[:], p)
+	}
+	return
+}
+
+func (d *digest) Sum(in []byte) []byte {
+	boring.Unreachable()
+	// Make a copy of d so that caller can keep writing and summing.
+	d0 := *d
+	hash := d0.checkSum()
+	if d0.is224 {
+		return append(in, hash[:Size224]...)
+	}
+	return append(in, hash[:]...)
+}
+
+func (d *digest) checkSum() [Size]byte {
+	len := d.len
+	// Padding. Add a 1 bit and 0 bits until 56 bytes mod 64.
+	var tmp [64]byte
+	tmp[0] = 0x80
+	if len%64 < 56 {
+		d.Write(tmp[0 : 56-len%64])
+	} else {
+		d.Write(tmp[0 : 64+56-len%64])
+	}
+
+	// Length in bits.
+	len <<= 3
+	binary.BigEndian.PutUint64(tmp[:], len)
+	d.Write(tmp[0:8])
+
+	if d.nx != 0 {
+		panic("d.nx != 0")
+	}
+
+	var digest [Size]byte
+
+	binary.BigEndian.PutUint32(digest[0:], d.h[0])
+	binary.BigEndian.PutUint32(digest[4:], d.h[1])
+	binary.BigEndian.PutUint32(digest[8:], d.h[2])
+	binary.BigEndian.PutUint32(digest[12:], d.h[3])
+	binary.BigEndian.PutUint32(digest[16:], d.h[4])
+	binary.BigEndian.PutUint32(digest[20:], d.h[5])
+	binary.BigEndian.PutUint32(digest[24:], d.h[6])
+	if !d.is224 {
+		binary.BigEndian.PutUint32(digest[28:], d.h[7])
+	}
+
+	return digest
+}
+
+// Sum256 returns the SHA256 checksum of the data.
+func Sum256(data []byte) [Size]byte {
+	if boring.Enabled {
+		return boring.SHA256(data)
+	}
+	var d digest
+	d.Reset()
+	d.Write(data)
+	return d.checkSum()
+}
+
+// Sum224 returns the SHA224 checksum of the data.
+func Sum224(data []byte) [Size224]byte {
+	if boring.Enabled {
+		return boring.SHA224(data)
+	}
+	var d digest
+	d.is224 = true
+	d.Reset()
+	d.Write(data)
+	sum := d.checkSum()
+	ap := (*[Size224]byte)(sum[:])
+	return *ap
+}
diff --git a/contrib/go/_std_1.18/src/crypto/sha256/sha256block.go b/contrib/go/_std_1.19/src/crypto/sha256/sha256block.go
index bd2f9da93c..bd2f9da93c 100644
--- a/contrib/go/_std_1.18/src/crypto/sha256/sha256block.go
+++ b/contrib/go/_std_1.19/src/crypto/sha256/sha256block.go
diff --git a/contrib/go/_std_1.18/src/crypto/sha256/sha256block_amd64.go b/contrib/go/_std_1.19/src/crypto/sha256/sha256block_amd64.go
index 27464e2c12..27464e2c12 100644
--- a/contrib/go/_std_1.18/src/crypto/sha256/sha256block_amd64.go
+++ b/contrib/go/_std_1.19/src/crypto/sha256/sha256block_amd64.go
diff --git a/contrib/go/_std_1.18/src/crypto/sha256/sha256block_amd64.s b/contrib/go/_std_1.19/src/crypto/sha256/sha256block_amd64.s
index f6af47c50e..f6af47c50e 100644
--- a/contrib/go/_std_1.18/src/crypto/sha256/sha256block_amd64.s
+++ b/contrib/go/_std_1.19/src/crypto/sha256/sha256block_amd64.s
diff --git a/contrib/go/_std_1.19/src/crypto/sha256/sha256block_decl.go b/contrib/go/_std_1.19/src/crypto/sha256/sha256block_decl.go
new file mode 100644
index 0000000000..18ba1c0ec1
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/sha256/sha256block_decl.go
@@ -0,0 +1,11 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build 386 || amd64 || s390x || ppc64le || ppc64
+
+package sha256
+
+//go:noescape
+
+func block(dig *digest, p []byte)
diff --git a/contrib/go/_std_1.19/src/crypto/sha512/sha512.go b/contrib/go/_std_1.19/src/crypto/sha512/sha512.go
new file mode 100644
index 0000000000..c800a294a2
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/sha512/sha512.go
@@ -0,0 +1,386 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package sha512 implements the SHA-384, SHA-512, SHA-512/224, and SHA-512/256
+// hash algorithms as defined in FIPS 180-4.
+//
+// All the hash.Hash implementations returned by this package also
+// implement encoding.BinaryMarshaler and encoding.BinaryUnmarshaler to
+// marshal and unmarshal the internal state of the hash.
+package sha512
+
+import (
+	"crypto"
+	"crypto/internal/boring"
+	"encoding/binary"
+	"errors"
+	"hash"
+)
+
+func init() {
+	crypto.RegisterHash(crypto.SHA384, New384)
+	crypto.RegisterHash(crypto.SHA512, New)
+	crypto.RegisterHash(crypto.SHA512_224, New512_224)
+	crypto.RegisterHash(crypto.SHA512_256, New512_256)
+}
+
+const (
+	// Size is the size, in bytes, of a SHA-512 checksum.
+	Size = 64
+
+	// Size224 is the size, in bytes, of a SHA-512/224 checksum.
+	Size224 = 28
+
+	// Size256 is the size, in bytes, of a SHA-512/256 checksum.
+	Size256 = 32
+
+	// Size384 is the size, in bytes, of a SHA-384 checksum.
+	Size384 = 48
+
+	// BlockSize is the block size, in bytes, of the SHA-512/224,
+	// SHA-512/256, SHA-384 and SHA-512 hash functions.
+	BlockSize = 128
+)
+
+const (
+	chunk     = 128
+	init0     = 0x6a09e667f3bcc908
+	init1     = 0xbb67ae8584caa73b
+	init2     = 0x3c6ef372fe94f82b
+	init3     = 0xa54ff53a5f1d36f1
+	init4     = 0x510e527fade682d1
+	init5     = 0x9b05688c2b3e6c1f
+	init6     = 0x1f83d9abfb41bd6b
+	init7     = 0x5be0cd19137e2179
+	init0_224 = 0x8c3d37c819544da2
+	init1_224 = 0x73e1996689dcd4d6
+	init2_224 = 0x1dfab7ae32ff9c82
+	init3_224 = 0x679dd514582f9fcf
+	init4_224 = 0x0f6d2b697bd44da8
+	init5_224 = 0x77e36f7304c48942
+	init6_224 = 0x3f9d85a86a1d36c8
+	init7_224 = 0x1112e6ad91d692a1
+	init0_256 = 0x22312194fc2bf72c
+	init1_256 = 0x9f555fa3c84c64c2
+	init2_256 = 0x2393b86b6f53b151
+	init3_256 = 0x963877195940eabd
+	init4_256 = 0x96283ee2a88effe3
+	init5_256 = 0xbe5e1e2553863992
+	init6_256 = 0x2b0199fc2c85b8aa
+	init7_256 = 0x0eb72ddc81c52ca2
+	init0_384 = 0xcbbb9d5dc1059ed8
+	init1_384 = 0x629a292a367cd507
+	init2_384 = 0x9159015a3070dd17
+	init3_384 = 0x152fecd8f70e5939
+	init4_384 = 0x67332667ffc00b31
+	init5_384 = 0x8eb44a8768581511
+	init6_384 = 0xdb0c2e0d64f98fa7
+	init7_384 = 0x47b5481dbefa4fa4
+)
+
+// digest represents the partial evaluation of a checksum.
+type digest struct {
+	h        [8]uint64
+	x        [chunk]byte
+	nx       int
+	len      uint64
+	function crypto.Hash
+}
+
+func (d *digest) Reset() {
+	switch d.function {
+	case crypto.SHA384:
+		d.h[0] = init0_384
+		d.h[1] = init1_384
+		d.h[2] = init2_384
+		d.h[3] = init3_384
+		d.h[4] = init4_384
+		d.h[5] = init5_384
+		d.h[6] = init6_384
+		d.h[7] = init7_384
+	case crypto.SHA512_224:
+		d.h[0] = init0_224
+		d.h[1] = init1_224
+		d.h[2] = init2_224
+		d.h[3] = init3_224
+		d.h[4] = init4_224
+		d.h[5] = init5_224
+		d.h[6] = init6_224
+		d.h[7] = init7_224
+	case crypto.SHA512_256:
+		d.h[0] = init0_256
+		d.h[1] = init1_256
+		d.h[2] = init2_256
+		d.h[3] = init3_256
+		d.h[4] = init4_256
+		d.h[5] = init5_256
+		d.h[6] = init6_256
+		d.h[7] = init7_256
+	default:
+		d.h[0] = init0
+		d.h[1] = init1
+		d.h[2] = init2
+		d.h[3] = init3
+		d.h[4] = init4
+		d.h[5] = init5
+		d.h[6] = init6
+		d.h[7] = init7
+	}
+	d.nx = 0
+	d.len = 0
+}
+
+const (
+	magic384      = "sha\x04"
+	magic512_224  = "sha\x05"
+	magic512_256  = "sha\x06"
+	magic512      = "sha\x07"
+	marshaledSize = len(magic512) + 8*8 + chunk + 8
+)
+
+func (d *digest) MarshalBinary() ([]byte, error) {
+	b := make([]byte, 0, marshaledSize)
+	switch d.function {
+	case crypto.SHA384:
+		b = append(b, magic384...)
+	case crypto.SHA512_224:
+		b = append(b, magic512_224...)
+	case crypto.SHA512_256:
+		b = append(b, magic512_256...)
+	case crypto.SHA512:
+		b = append(b, magic512...)
+	default:
+		return nil, errors.New("crypto/sha512: invalid hash function")
+	}
+	b = appendUint64(b, d.h[0])
+	b = appendUint64(b, d.h[1])
+	b = appendUint64(b, d.h[2])
+	b = appendUint64(b, d.h[3])
+	b = appendUint64(b, d.h[4])
+	b = appendUint64(b, d.h[5])
+	b = appendUint64(b, d.h[6])
+	b = appendUint64(b, d.h[7])
+	b = append(b, d.x[:d.nx]...)
+	b = b[:len(b)+len(d.x)-int(d.nx)] // already zero
+	b = appendUint64(b, d.len)
+	return b, nil
+}
+
+func (d *digest) UnmarshalBinary(b []byte) error {
+	if len(b) < len(magic512) {
+		return errors.New("crypto/sha512: invalid hash state identifier")
+	}
+	switch {
+	case d.function == crypto.SHA384 && string(b[:len(magic384)]) == magic384:
+	case d.function == crypto.SHA512_224 && string(b[:len(magic512_224)]) == magic512_224:
+	case d.function == crypto.SHA512_256 && string(b[:len(magic512_256)]) == magic512_256:
+	case d.function == crypto.SHA512 && string(b[:len(magic512)]) == magic512:
+	default:
+		return errors.New("crypto/sha512: invalid hash state identifier")
+	}
+	if len(b) != marshaledSize {
+		return errors.New("crypto/sha512: invalid hash state size")
+	}
+	b = b[len(magic512):]
+	b, d.h[0] = consumeUint64(b)
+	b, d.h[1] = consumeUint64(b)
+	b, d.h[2] = consumeUint64(b)
+	b, d.h[3] = consumeUint64(b)
+	b, d.h[4] = consumeUint64(b)
+	b, d.h[5] = consumeUint64(b)
+	b, d.h[6] = consumeUint64(b)
+	b, d.h[7] = consumeUint64(b)
+	b = b[copy(d.x[:], b):]
+	b, d.len = consumeUint64(b)
+	d.nx = int(d.len % chunk)
+	return nil
+}
+
+func appendUint64(b []byte, x uint64) []byte {
+	var a [8]byte
+	binary.BigEndian.PutUint64(a[:], x)
+	return append(b, a[:]...)
+}
+
+func consumeUint64(b []byte) ([]byte, uint64) {
+	_ = b[7]
+	x := uint64(b[7]) | uint64(b[6])<<8 | uint64(b[5])<<16 | uint64(b[4])<<24 |
+		uint64(b[3])<<32 | uint64(b[2])<<40 | uint64(b[1])<<48 | uint64(b[0])<<56
+	return b[8:], x
+}
+
+// New returns a new hash.Hash computing the SHA-512 checksum.
+func New() hash.Hash {
+	if boring.Enabled {
+		return boring.NewSHA512()
+	}
+	d := &digest{function: crypto.SHA512}
+	d.Reset()
+	return d
+}
+
+// New512_224 returns a new hash.Hash computing the SHA-512/224 checksum.
+func New512_224() hash.Hash {
+	d := &digest{function: crypto.SHA512_224}
+	d.Reset()
+	return d
+}
+
+// New512_256 returns a new hash.Hash computing the SHA-512/256 checksum.
+func New512_256() hash.Hash {
+	d := &digest{function: crypto.SHA512_256}
+	d.Reset()
+	return d
+}
+
+// New384 returns a new hash.Hash computing the SHA-384 checksum.
+func New384() hash.Hash {
+	if boring.Enabled {
+		return boring.NewSHA384()
+	}
+	d := &digest{function: crypto.SHA384}
+	d.Reset()
+	return d
+}
+
+func (d *digest) Size() int {
+	switch d.function {
+	case crypto.SHA512_224:
+		return Size224
+	case crypto.SHA512_256:
+		return Size256
+	case crypto.SHA384:
+		return Size384
+	default:
+		return Size
+	}
+}
+
+func (d *digest) BlockSize() int { return BlockSize }
+
+func (d *digest) Write(p []byte) (nn int, err error) {
+	if d.function != crypto.SHA512_224 && d.function != crypto.SHA512_256 {
+		boring.Unreachable()
+	}
+	nn = len(p)
+	d.len += uint64(nn)
+	if d.nx > 0 {
+		n := copy(d.x[d.nx:], p)
+		d.nx += n
+		if d.nx == chunk {
+			block(d, d.x[:])
+			d.nx = 0
+		}
+		p = p[n:]
+	}
+	if len(p) >= chunk {
+		n := len(p) &^ (chunk - 1)
+		block(d, p[:n])
+		p = p[n:]
+	}
+	if len(p) > 0 {
+		d.nx = copy(d.x[:], p)
+	}
+	return
+}
+
+func (d *digest) Sum(in []byte) []byte {
+	if d.function != crypto.SHA512_224 && d.function != crypto.SHA512_256 {
+		boring.Unreachable()
+	}
+	// Make a copy of d so that caller can keep writing and summing.
+	d0 := new(digest)
+	*d0 = *d
+	hash := d0.checkSum()
+	switch d0.function {
+	case crypto.SHA384:
+		return append(in, hash[:Size384]...)
+	case crypto.SHA512_224:
+		return append(in, hash[:Size224]...)
+	case crypto.SHA512_256:
+		return append(in, hash[:Size256]...)
+	default:
+		return append(in, hash[:]...)
+	}
+}
+
+func (d *digest) checkSum() [Size]byte {
+	// Padding. Add a 1 bit and 0 bits until 112 bytes mod 128.
+	len := d.len
+	var tmp [128]byte
+	tmp[0] = 0x80
+	if len%128 < 112 {
+		d.Write(tmp[0 : 112-len%128])
+	} else {
+		d.Write(tmp[0 : 128+112-len%128])
+	}
+
+	// Length in bits.
+	len <<= 3
+	binary.BigEndian.PutUint64(tmp[0:], 0) // upper 64 bits are always zero, because len variable has type uint64
+	binary.BigEndian.PutUint64(tmp[8:], len)
+	d.Write(tmp[0:16])
+
+	if d.nx != 0 {
+		panic("d.nx != 0")
+	}
+
+	var digest [Size]byte
+	binary.BigEndian.PutUint64(digest[0:], d.h[0])
+	binary.BigEndian.PutUint64(digest[8:], d.h[1])
+	binary.BigEndian.PutUint64(digest[16:], d.h[2])
+	binary.BigEndian.PutUint64(digest[24:], d.h[3])
+	binary.BigEndian.PutUint64(digest[32:], d.h[4])
+	binary.BigEndian.PutUint64(digest[40:], d.h[5])
+	if d.function != crypto.SHA384 {
+		binary.BigEndian.PutUint64(digest[48:], d.h[6])
+		binary.BigEndian.PutUint64(digest[56:], d.h[7])
+	}
+
+	return digest
+}
+
+// Sum512 returns the SHA512 checksum of the data.
+func Sum512(data []byte) [Size]byte {
+	if boring.Enabled {
+		return boring.SHA512(data)
+	}
+	d := digest{function: crypto.SHA512}
+	d.Reset()
+	d.Write(data)
+	return d.checkSum()
+}
+
+// Sum384 returns the SHA384 checksum of the data.
+func Sum384(data []byte) [Size384]byte {
+	if boring.Enabled {
+		return boring.SHA384(data)
+	}
+	d := digest{function: crypto.SHA384}
+	d.Reset()
+	d.Write(data)
+	sum := d.checkSum()
+	ap := (*[Size384]byte)(sum[:])
+	return *ap
+}
+
+// Sum512_224 returns the Sum512/224 checksum of the data.
+func Sum512_224(data []byte) [Size224]byte {
+	d := digest{function: crypto.SHA512_224}
+	d.Reset()
+	d.Write(data)
+	sum := d.checkSum()
+	ap := (*[Size224]byte)(sum[:])
+	return *ap
+}
+
+// Sum512_256 returns the Sum512/256 checksum of the data.
+func Sum512_256(data []byte) [Size256]byte {
+	d := digest{function: crypto.SHA512_256}
+	d.Reset()
+	d.Write(data)
+	sum := d.checkSum()
+	ap := (*[Size256]byte)(sum[:])
+	return *ap
+}
diff --git a/contrib/go/_std_1.18/src/crypto/sha512/sha512block.go b/contrib/go/_std_1.19/src/crypto/sha512/sha512block.go
index 81569c5f84..81569c5f84 100644
--- a/contrib/go/_std_1.18/src/crypto/sha512/sha512block.go
+++ b/contrib/go/_std_1.19/src/crypto/sha512/sha512block.go
diff --git a/contrib/go/_std_1.18/src/crypto/sha512/sha512block_amd64.go b/contrib/go/_std_1.19/src/crypto/sha512/sha512block_amd64.go
index 8da3e1473f..8da3e1473f 100644
--- a/contrib/go/_std_1.18/src/crypto/sha512/sha512block_amd64.go
+++ b/contrib/go/_std_1.19/src/crypto/sha512/sha512block_amd64.go
diff --git a/contrib/go/_std_1.18/src/crypto/sha512/sha512block_amd64.s b/contrib/go/_std_1.19/src/crypto/sha512/sha512block_amd64.s
index 0fa0df2f60..0fa0df2f60 100644
--- a/contrib/go/_std_1.18/src/crypto/sha512/sha512block_amd64.s
+++ b/contrib/go/_std_1.19/src/crypto/sha512/sha512block_amd64.s
diff --git a/contrib/go/_std_1.19/src/crypto/subtle/constant_time.go b/contrib/go/_std_1.19/src/crypto/subtle/constant_time.go
new file mode 100644
index 0000000000..4e0527f9d5
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/subtle/constant_time.go
@@ -0,0 +1,62 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package subtle implements functions that are often useful in cryptographic
+// code but require careful thought to use correctly.
+package subtle
+
+// ConstantTimeCompare returns 1 if the two slices, x and y, have equal contents
+// and 0 otherwise. The time taken is a function of the length of the slices and
+// is independent of the contents. If the lengths of x and y do not match it
+// returns 0 immediately.
+func ConstantTimeCompare(x, y []byte) int {
+	if len(x) != len(y) {
+		return 0
+	}
+
+	var v byte
+
+	for i := 0; i < len(x); i++ {
+		v |= x[i] ^ y[i]
+	}
+
+	return ConstantTimeByteEq(v, 0)
+}
+
+// ConstantTimeSelect returns x if v == 1 and y if v == 0.
+// Its behavior is undefined if v takes any other value.
+func ConstantTimeSelect(v, x, y int) int { return ^(v-1)&x | (v-1)&y }
+
+// ConstantTimeByteEq returns 1 if x == y and 0 otherwise.
+func ConstantTimeByteEq(x, y uint8) int {
+	return int((uint32(x^y) - 1) >> 31)
+}
+
+// ConstantTimeEq returns 1 if x == y and 0 otherwise.
+func ConstantTimeEq(x, y int32) int {
+	return int((uint64(uint32(x^y)) - 1) >> 63)
+}
+
+// ConstantTimeCopy copies the contents of y into x (a slice of equal length)
+// if v == 1. If v == 0, x is left unchanged. Its behavior is undefined if v
+// takes any other value.
+func ConstantTimeCopy(v int, x, y []byte) {
+	if len(x) != len(y) {
+		panic("subtle: slices have different lengths")
+	}
+
+	xmask := byte(v - 1)
+	ymask := byte(^(v - 1))
+	for i := 0; i < len(x); i++ {
+		x[i] = x[i]&xmask | y[i]&ymask
+	}
+}
+
+// ConstantTimeLessOrEq returns 1 if x <= y and 0 otherwise.
+// Its behavior is undefined if x or y are negative or > 2**31 - 1.
+func ConstantTimeLessOrEq(x, y int) int {
+	x32 := int32(x)
+	y32 := int32(y)
+	return int(((x32 - y32 - 1) >> 31) & 1)
+}
diff --git a/contrib/go/_std_1.18/src/crypto/tls/alert.go b/contrib/go/_std_1.19/src/crypto/tls/alert.go
index 4790b73724..4790b73724 100644
--- a/contrib/go/_std_1.18/src/crypto/tls/alert.go
+++ b/contrib/go/_std_1.19/src/crypto/tls/alert.go
diff --git a/contrib/go/_std_1.19/src/crypto/tls/auth.go b/contrib/go/_std_1.19/src/crypto/tls/auth.go
new file mode 100644
index 0000000000..7c5675c6d9
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/tls/auth.go
@@ -0,0 +1,293 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package tls
+
+import (
+	"bytes"
+	"crypto"
+	"crypto/ecdsa"
+	"crypto/ed25519"
+	"crypto/elliptic"
+	"crypto/rsa"
+	"errors"
+	"fmt"
+	"hash"
+	"io"
+)
+
+// verifyHandshakeSignature verifies a signature against pre-hashed
+// (if required) handshake contents.
+func verifyHandshakeSignature(sigType uint8, pubkey crypto.PublicKey, hashFunc crypto.Hash, signed, sig []byte) error {
+	switch sigType {
+	case signatureECDSA:
+		pubKey, ok := pubkey.(*ecdsa.PublicKey)
+		if !ok {
+			return fmt.Errorf("expected an ECDSA public key, got %T", pubkey)
+		}
+		if !ecdsa.VerifyASN1(pubKey, signed, sig) {
+			return errors.New("ECDSA verification failure")
+		}
+	case signatureEd25519:
+		pubKey, ok := pubkey.(ed25519.PublicKey)
+		if !ok {
+			return fmt.Errorf("expected an Ed25519 public key, got %T", pubkey)
+		}
+		if !ed25519.Verify(pubKey, signed, sig) {
+			return errors.New("Ed25519 verification failure")
+		}
+	case signaturePKCS1v15:
+		pubKey, ok := pubkey.(*rsa.PublicKey)
+		if !ok {
+			return fmt.Errorf("expected an RSA public key, got %T", pubkey)
+		}
+		if err := rsa.VerifyPKCS1v15(pubKey, hashFunc, signed, sig); err != nil {
+			return err
+		}
+	case signatureRSAPSS:
+		pubKey, ok := pubkey.(*rsa.PublicKey)
+		if !ok {
+			return fmt.Errorf("expected an RSA public key, got %T", pubkey)
+		}
+		signOpts := &rsa.PSSOptions{SaltLength: rsa.PSSSaltLengthEqualsHash}
+		if err := rsa.VerifyPSS(pubKey, hashFunc, signed, sig, signOpts); err != nil {
+			return err
+		}
+	default:
+		return errors.New("internal error: unknown signature type")
+	}
+	return nil
+}
+
+const (
+	serverSignatureContext = "TLS 1.3, server CertificateVerify\x00"
+	clientSignatureContext = "TLS 1.3, client CertificateVerify\x00"
+)
+
+var signaturePadding = []byte{
+	0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+	0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+	0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+	0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+	0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+	0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+	0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+	0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+}
+
+// signedMessage returns the pre-hashed (if necessary) message to be signed by
+// certificate keys in TLS 1.3. See RFC 8446, Section 4.4.3.
+func signedMessage(sigHash crypto.Hash, context string, transcript hash.Hash) []byte {
+	if sigHash == directSigning {
+		b := &bytes.Buffer{}
+		b.Write(signaturePadding)
+		io.WriteString(b, context)
+		b.Write(transcript.Sum(nil))
+		return b.Bytes()
+	}
+	h := sigHash.New()
+	h.Write(signaturePadding)
+	io.WriteString(h, context)
+	h.Write(transcript.Sum(nil))
+	return h.Sum(nil)
+}
+
+// typeAndHashFromSignatureScheme returns the corresponding signature type and
+// crypto.Hash for a given TLS SignatureScheme.
+func typeAndHashFromSignatureScheme(signatureAlgorithm SignatureScheme) (sigType uint8, hash crypto.Hash, err error) {
+	switch signatureAlgorithm {
+	case PKCS1WithSHA1, PKCS1WithSHA256, PKCS1WithSHA384, PKCS1WithSHA512:
+		sigType = signaturePKCS1v15
+	case PSSWithSHA256, PSSWithSHA384, PSSWithSHA512:
+		sigType = signatureRSAPSS
+	case ECDSAWithSHA1, ECDSAWithP256AndSHA256, ECDSAWithP384AndSHA384, ECDSAWithP521AndSHA512:
+		sigType = signatureECDSA
+	case Ed25519:
+		sigType = signatureEd25519
+	default:
+		return 0, 0, fmt.Errorf("unsupported signature algorithm: %v", signatureAlgorithm)
+	}
+	switch signatureAlgorithm {
+	case PKCS1WithSHA1, ECDSAWithSHA1:
+		hash = crypto.SHA1
+	case PKCS1WithSHA256, PSSWithSHA256, ECDSAWithP256AndSHA256:
+		hash = crypto.SHA256
+	case PKCS1WithSHA384, PSSWithSHA384, ECDSAWithP384AndSHA384:
+		hash = crypto.SHA384
+	case PKCS1WithSHA512, PSSWithSHA512, ECDSAWithP521AndSHA512:
+		hash = crypto.SHA512
+	case Ed25519:
+		hash = directSigning
+	default:
+		return 0, 0, fmt.Errorf("unsupported signature algorithm: %v", signatureAlgorithm)
+	}
+	return sigType, hash, nil
+}
+
+// legacyTypeAndHashFromPublicKey returns the fixed signature type and crypto.Hash for
+// a given public key used with TLS 1.0 and 1.1, before the introduction of
+// signature algorithm negotiation.
+func legacyTypeAndHashFromPublicKey(pub crypto.PublicKey) (sigType uint8, hash crypto.Hash, err error) {
+	switch pub.(type) {
+	case *rsa.PublicKey:
+		return signaturePKCS1v15, crypto.MD5SHA1, nil
+	case *ecdsa.PublicKey:
+		return signatureECDSA, crypto.SHA1, nil
+	case ed25519.PublicKey:
+		// RFC 8422 specifies support for Ed25519 in TLS 1.0 and 1.1,
+		// but it requires holding on to a handshake transcript to do a
+		// full signature, and not even OpenSSL bothers with the
+		// complexity, so we can't even test it properly.
+		return 0, 0, fmt.Errorf("tls: Ed25519 public keys are not supported before TLS 1.2")
+	default:
+		return 0, 0, fmt.Errorf("tls: unsupported public key: %T", pub)
+	}
+}
+
+var rsaSignatureSchemes = []struct {
+	scheme          SignatureScheme
+	minModulusBytes int
+	maxVersion      uint16
+}{
+	// RSA-PSS is used with PSSSaltLengthEqualsHash, and requires
+	//    emLen >= hLen + sLen + 2
+	{PSSWithSHA256, crypto.SHA256.Size()*2 + 2, VersionTLS13},
+	{PSSWithSHA384, crypto.SHA384.Size()*2 + 2, VersionTLS13},
+	{PSSWithSHA512, crypto.SHA512.Size()*2 + 2, VersionTLS13},
+	// PKCS #1 v1.5 uses prefixes from hashPrefixes in crypto/rsa, and requires
+	//    emLen >= len(prefix) + hLen + 11
+	// TLS 1.3 dropped support for PKCS #1 v1.5 in favor of RSA-PSS.
+	{PKCS1WithSHA256, 19 + crypto.SHA256.Size() + 11, VersionTLS12},
+	{PKCS1WithSHA384, 19 + crypto.SHA384.Size() + 11, VersionTLS12},
+	{PKCS1WithSHA512, 19 + crypto.SHA512.Size() + 11, VersionTLS12},
+	{PKCS1WithSHA1, 15 + crypto.SHA1.Size() + 11, VersionTLS12},
+}
+
+// signatureSchemesForCertificate returns the list of supported SignatureSchemes
+// for a given certificate, based on the public key and the protocol version,
+// and optionally filtered by its explicit SupportedSignatureAlgorithms.
+//
+// This function must be kept in sync with supportedSignatureAlgorithms.
+// FIPS filtering is applied in the caller, selectSignatureScheme.
+func signatureSchemesForCertificate(version uint16, cert *Certificate) []SignatureScheme {
+	priv, ok := cert.PrivateKey.(crypto.Signer)
+	if !ok {
+		return nil
+	}
+
+	var sigAlgs []SignatureScheme
+	switch pub := priv.Public().(type) {
+	case *ecdsa.PublicKey:
+		if version != VersionTLS13 {
+			// In TLS 1.2 and earlier, ECDSA algorithms are not
+			// constrained to a single curve.
+			sigAlgs = []SignatureScheme{
+				ECDSAWithP256AndSHA256,
+				ECDSAWithP384AndSHA384,
+				ECDSAWithP521AndSHA512,
+				ECDSAWithSHA1,
+			}
+			break
+		}
+		switch pub.Curve {
+		case elliptic.P256():
+			sigAlgs = []SignatureScheme{ECDSAWithP256AndSHA256}
+		case elliptic.P384():
+			sigAlgs = []SignatureScheme{ECDSAWithP384AndSHA384}
+		case elliptic.P521():
+			sigAlgs = []SignatureScheme{ECDSAWithP521AndSHA512}
+		default:
+			return nil
+		}
+	case *rsa.PublicKey:
+		size := pub.Size()
+		sigAlgs = make([]SignatureScheme, 0, len(rsaSignatureSchemes))
+		for _, candidate := range rsaSignatureSchemes {
+			if size >= candidate.minModulusBytes && version <= candidate.maxVersion {
+				sigAlgs = append(sigAlgs, candidate.scheme)
+			}
+		}
+	case ed25519.PublicKey:
+		sigAlgs = []SignatureScheme{Ed25519}
+	default:
+		return nil
+	}
+
+	if cert.SupportedSignatureAlgorithms != nil {
+		var filteredSigAlgs []SignatureScheme
+		for _, sigAlg := range sigAlgs {
+			if isSupportedSignatureAlgorithm(sigAlg, cert.SupportedSignatureAlgorithms) {
+				filteredSigAlgs = append(filteredSigAlgs, sigAlg)
+			}
+		}
+		return filteredSigAlgs
+	}
+	return sigAlgs
+}
+
+// selectSignatureScheme picks a SignatureScheme from the peer's preference list
+// that works with the selected certificate. It's only called for protocol
+// versions that support signature algorithms, so TLS 1.2 and 1.3.
+func selectSignatureScheme(vers uint16, c *Certificate, peerAlgs []SignatureScheme) (SignatureScheme, error) {
+	supportedAlgs := signatureSchemesForCertificate(vers, c)
+	if len(supportedAlgs) == 0 {
+		return 0, unsupportedCertificateError(c)
+	}
+	if len(peerAlgs) == 0 && vers == VersionTLS12 {
+		// For TLS 1.2, if the client didn't send signature_algorithms then we
+		// can assume that it supports SHA1. See RFC 5246, Section 7.4.1.4.1.
+		peerAlgs = []SignatureScheme{PKCS1WithSHA1, ECDSAWithSHA1}
+	}
+	// Pick signature scheme in the peer's preference order, as our
+	// preference order is not configurable.
+	for _, preferredAlg := range peerAlgs {
+		if needFIPS() && !isSupportedSignatureAlgorithm(preferredAlg, fipsSupportedSignatureAlgorithms) {
+			continue
+		}
+		if isSupportedSignatureAlgorithm(preferredAlg, supportedAlgs) {
+			return preferredAlg, nil
+		}
+	}
+	return 0, errors.New("tls: peer doesn't support any of the certificate's signature algorithms")
+}
+
+// unsupportedCertificateError returns a helpful error for certificates with
+// an unsupported private key.
+func unsupportedCertificateError(cert *Certificate) error {
+	switch cert.PrivateKey.(type) {
+	case rsa.PrivateKey, ecdsa.PrivateKey:
+		return fmt.Errorf("tls: unsupported certificate: private key is %T, expected *%T",
+			cert.PrivateKey, cert.PrivateKey)
+	case *ed25519.PrivateKey:
+		return fmt.Errorf("tls: unsupported certificate: private key is *ed25519.PrivateKey, expected ed25519.PrivateKey")
+	}
+
+	signer, ok := cert.PrivateKey.(crypto.Signer)
+	if !ok {
+		return fmt.Errorf("tls: certificate private key (%T) does not implement crypto.Signer",
+			cert.PrivateKey)
+	}
+
+	switch pub := signer.Public().(type) {
+	case *ecdsa.PublicKey:
+		switch pub.Curve {
+		case elliptic.P256():
+		case elliptic.P384():
+		case elliptic.P521():
+		default:
+			return fmt.Errorf("tls: unsupported certificate curve (%s)", pub.Curve.Params().Name)
+		}
+	case *rsa.PublicKey:
+		return fmt.Errorf("tls: certificate RSA key size too small for supported signature algorithms")
+	case ed25519.PublicKey:
+	default:
+		return fmt.Errorf("tls: unsupported certificate key (%T)", pub)
+	}
+
+	if cert.SupportedSignatureAlgorithms != nil {
+		return fmt.Errorf("tls: peer doesn't support the certificate custom signature algorithms")
+	}
+
+	return fmt.Errorf("tls: internal error: unsupported key (%T)", cert.PrivateKey)
+}
diff --git a/contrib/go/_std_1.19/src/crypto/tls/cipher_suites.go b/contrib/go/_std_1.19/src/crypto/tls/cipher_suites.go
new file mode 100644
index 0000000000..9a1fa3104b
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/tls/cipher_suites.go
@@ -0,0 +1,702 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package tls
+
+import (
+	"crypto"
+	"crypto/aes"
+	"crypto/cipher"
+	"crypto/des"
+	"crypto/hmac"
+	"crypto/internal/boring"
+	"crypto/rc4"
+	"crypto/sha1"
+	"crypto/sha256"
+	"fmt"
+	"hash"
+	"internal/cpu"
+	"runtime"
+
+	"golang.org/x/crypto/chacha20poly1305"
+)
+
+// CipherSuite is a TLS cipher suite. Note that most functions in this package
+// accept and expose cipher suite IDs instead of this type.
+type CipherSuite struct {
+	ID   uint16
+	Name string
+
+	// Supported versions is the list of TLS protocol versions that can
+	// negotiate this cipher suite.
+	SupportedVersions []uint16
+
+	// Insecure is true if the cipher suite has known security issues
+	// due to its primitives, design, or implementation.
+	Insecure bool
+}
+
+var (
+	supportedUpToTLS12 = []uint16{VersionTLS10, VersionTLS11, VersionTLS12}
+	supportedOnlyTLS12 = []uint16{VersionTLS12}
+	supportedOnlyTLS13 = []uint16{VersionTLS13}
+)
+
+// CipherSuites returns a list of cipher suites currently implemented by this
+// package, excluding those with security issues, which are returned by
+// InsecureCipherSuites.
+//
+// The list is sorted by ID. Note that the default cipher suites selected by
+// this package might depend on logic that can't be captured by a static list,
+// and might not match those returned by this function.
+func CipherSuites() []*CipherSuite {
+	return []*CipherSuite{
+		{TLS_RSA_WITH_AES_128_CBC_SHA, "TLS_RSA_WITH_AES_128_CBC_SHA", supportedUpToTLS12, false},
+		{TLS_RSA_WITH_AES_256_CBC_SHA, "TLS_RSA_WITH_AES_256_CBC_SHA", supportedUpToTLS12, false},
+		{TLS_RSA_WITH_AES_128_GCM_SHA256, "TLS_RSA_WITH_AES_128_GCM_SHA256", supportedOnlyTLS12, false},
+		{TLS_RSA_WITH_AES_256_GCM_SHA384, "TLS_RSA_WITH_AES_256_GCM_SHA384", supportedOnlyTLS12, false},
+
+		{TLS_AES_128_GCM_SHA256, "TLS_AES_128_GCM_SHA256", supportedOnlyTLS13, false},
+		{TLS_AES_256_GCM_SHA384, "TLS_AES_256_GCM_SHA384", supportedOnlyTLS13, false},
+		{TLS_CHACHA20_POLY1305_SHA256, "TLS_CHACHA20_POLY1305_SHA256", supportedOnlyTLS13, false},
+
+		{TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA, "TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA", supportedUpToTLS12, false},
+		{TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA, "TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA", supportedUpToTLS12, false},
+		{TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA, "TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA", supportedUpToTLS12, false},
+		{TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA, "TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA", supportedUpToTLS12, false},
+		{TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256, "TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256", supportedOnlyTLS12, false},
+		{TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384, "TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384", supportedOnlyTLS12, false},
+		{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256, "TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256", supportedOnlyTLS12, false},
+		{TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384, "TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384", supportedOnlyTLS12, false},
+		{TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256, "TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256", supportedOnlyTLS12, false},
+		{TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256, "TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256", supportedOnlyTLS12, false},
+	}
+}
+
+// InsecureCipherSuites returns a list of cipher suites currently implemented by
+// this package and which have security issues.
+//
+// Most applications should not use the cipher suites in this list, and should
+// only use those returned by CipherSuites.
+func InsecureCipherSuites() []*CipherSuite {
+	// This list includes RC4, CBC_SHA256, and 3DES cipher suites. See
+	// cipherSuitesPreferenceOrder for details.
+	return []*CipherSuite{
+		{TLS_RSA_WITH_RC4_128_SHA, "TLS_RSA_WITH_RC4_128_SHA", supportedUpToTLS12, true},
+		{TLS_RSA_WITH_3DES_EDE_CBC_SHA, "TLS_RSA_WITH_3DES_EDE_CBC_SHA", supportedUpToTLS12, true},
+		{TLS_RSA_WITH_AES_128_CBC_SHA256, "TLS_RSA_WITH_AES_128_CBC_SHA256", supportedOnlyTLS12, true},
+		{TLS_ECDHE_ECDSA_WITH_RC4_128_SHA, "TLS_ECDHE_ECDSA_WITH_RC4_128_SHA", supportedUpToTLS12, true},
+		{TLS_ECDHE_RSA_WITH_RC4_128_SHA, "TLS_ECDHE_RSA_WITH_RC4_128_SHA", supportedUpToTLS12, true},
+		{TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA, "TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA", supportedUpToTLS12, true},
+		{TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256, "TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256", supportedOnlyTLS12, true},
+		{TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256, "TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256", supportedOnlyTLS12, true},
+	}
+}
+
+// CipherSuiteName returns the standard name for the passed cipher suite ID
+// (e.g. "TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256"), or a fallback representation
+// of the ID value if the cipher suite is not implemented by this package.
+func CipherSuiteName(id uint16) string {
+	for _, c := range CipherSuites() {
+		if c.ID == id {
+			return c.Name
+		}
+	}
+	for _, c := range InsecureCipherSuites() {
+		if c.ID == id {
+			return c.Name
+		}
+	}
+	return fmt.Sprintf("0x%04X", id)
+}
+
+const (
+	// suiteECDHE indicates that the cipher suite involves elliptic curve
+	// Diffie-Hellman. This means that it should only be selected when the
+	// client indicates that it supports ECC with a curve and point format
+	// that we're happy with.
+	suiteECDHE = 1 << iota
+	// suiteECSign indicates that the cipher suite involves an ECDSA or
+	// EdDSA signature and therefore may only be selected when the server's
+	// certificate is ECDSA or EdDSA. If this is not set then the cipher suite
+	// is RSA based.
+	suiteECSign
+	// suiteTLS12 indicates that the cipher suite should only be advertised
+	// and accepted when using TLS 1.2.
+	suiteTLS12
+	// suiteSHA384 indicates that the cipher suite uses SHA384 as the
+	// handshake hash.
+	suiteSHA384
+)
+
+// A cipherSuite is a TLS 1.0–1.2 cipher suite, and defines the key exchange
+// mechanism, as well as the cipher+MAC pair or the AEAD.
+type cipherSuite struct {
+	id uint16
+	// the lengths, in bytes, of the key material needed for each component.
+	keyLen int
+	macLen int
+	ivLen  int
+	ka     func(version uint16) keyAgreement
+	// flags is a bitmask of the suite* values, above.
+	flags  int
+	cipher func(key, iv []byte, isRead bool) any
+	mac    func(key []byte) hash.Hash
+	aead   func(key, fixedNonce []byte) aead
+}
+
+var cipherSuites = []*cipherSuite{ // TODO: replace with a map, since the order doesn't matter.
+	{TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305, 32, 0, 12, ecdheRSAKA, suiteECDHE | suiteTLS12, nil, nil, aeadChaCha20Poly1305},
+	{TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305, 32, 0, 12, ecdheECDSAKA, suiteECDHE | suiteECSign | suiteTLS12, nil, nil, aeadChaCha20Poly1305},
+	{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256, 16, 0, 4, ecdheRSAKA, suiteECDHE | suiteTLS12, nil, nil, aeadAESGCM},
+	{TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256, 16, 0, 4, ecdheECDSAKA, suiteECDHE | suiteECSign | suiteTLS12, nil, nil, aeadAESGCM},
+	{TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384, 32, 0, 4, ecdheRSAKA, suiteECDHE | suiteTLS12 | suiteSHA384, nil, nil, aeadAESGCM},
+	{TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384, 32, 0, 4, ecdheECDSAKA, suiteECDHE | suiteECSign | suiteTLS12 | suiteSHA384, nil, nil, aeadAESGCM},
+	{TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256, 16, 32, 16, ecdheRSAKA, suiteECDHE | suiteTLS12, cipherAES, macSHA256, nil},
+	{TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA, 16, 20, 16, ecdheRSAKA, suiteECDHE, cipherAES, macSHA1, nil},
+	{TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256, 16, 32, 16, ecdheECDSAKA, suiteECDHE | suiteECSign | suiteTLS12, cipherAES, macSHA256, nil},
+	{TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA, 16, 20, 16, ecdheECDSAKA, suiteECDHE | suiteECSign, cipherAES, macSHA1, nil},
+	{TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA, 32, 20, 16, ecdheRSAKA, suiteECDHE, cipherAES, macSHA1, nil},
+	{TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA, 32, 20, 16, ecdheECDSAKA, suiteECDHE | suiteECSign, cipherAES, macSHA1, nil},
+	{TLS_RSA_WITH_AES_128_GCM_SHA256, 16, 0, 4, rsaKA, suiteTLS12, nil, nil, aeadAESGCM},
+	{TLS_RSA_WITH_AES_256_GCM_SHA384, 32, 0, 4, rsaKA, suiteTLS12 | suiteSHA384, nil, nil, aeadAESGCM},
+	{TLS_RSA_WITH_AES_128_CBC_SHA256, 16, 32, 16, rsaKA, suiteTLS12, cipherAES, macSHA256, nil},
+	{TLS_RSA_WITH_AES_128_CBC_SHA, 16, 20, 16, rsaKA, 0, cipherAES, macSHA1, nil},
+	{TLS_RSA_WITH_AES_256_CBC_SHA, 32, 20, 16, rsaKA, 0, cipherAES, macSHA1, nil},
+	{TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA, 24, 20, 8, ecdheRSAKA, suiteECDHE, cipher3DES, macSHA1, nil},
+	{TLS_RSA_WITH_3DES_EDE_CBC_SHA, 24, 20, 8, rsaKA, 0, cipher3DES, macSHA1, nil},
+	{TLS_RSA_WITH_RC4_128_SHA, 16, 20, 0, rsaKA, 0, cipherRC4, macSHA1, nil},
+	{TLS_ECDHE_RSA_WITH_RC4_128_SHA, 16, 20, 0, ecdheRSAKA, suiteECDHE, cipherRC4, macSHA1, nil},
+	{TLS_ECDHE_ECDSA_WITH_RC4_128_SHA, 16, 20, 0, ecdheECDSAKA, suiteECDHE | suiteECSign, cipherRC4, macSHA1, nil},
+}
+
+// selectCipherSuite returns the first TLS 1.0–1.2 cipher suite from ids which
+// is also in supportedIDs and passes the ok filter.
+func selectCipherSuite(ids, supportedIDs []uint16, ok func(*cipherSuite) bool) *cipherSuite {
+	for _, id := range ids {
+		candidate := cipherSuiteByID(id)
+		if candidate == nil || !ok(candidate) {
+			continue
+		}
+
+		for _, suppID := range supportedIDs {
+			if id == suppID {
+				return candidate
+			}
+		}
+	}
+	return nil
+}
+
+// A cipherSuiteTLS13 defines only the pair of the AEAD algorithm and hash
+// algorithm to be used with HKDF. See RFC 8446, Appendix B.4.
+type cipherSuiteTLS13 struct {
+	id     uint16
+	keyLen int
+	aead   func(key, fixedNonce []byte) aead
+	hash   crypto.Hash
+}
+
+var cipherSuitesTLS13 = []*cipherSuiteTLS13{ // TODO: replace with a map.
+	{TLS_AES_128_GCM_SHA256, 16, aeadAESGCMTLS13, crypto.SHA256},
+	{TLS_CHACHA20_POLY1305_SHA256, 32, aeadChaCha20Poly1305, crypto.SHA256},
+	{TLS_AES_256_GCM_SHA384, 32, aeadAESGCMTLS13, crypto.SHA384},
+}
+
+// cipherSuitesPreferenceOrder is the order in which we'll select (on the
+// server) or advertise (on the client) TLS 1.0–1.2 cipher suites.
+//
+// Cipher suites are filtered but not reordered based on the application and
+// peer's preferences, meaning we'll never select a suite lower in this list if
+// any higher one is available. This makes it more defensible to keep weaker
+// cipher suites enabled, especially on the server side where we get the last
+// word, since there are no known downgrade attacks on cipher suites selection.
+//
+// The list is sorted by applying the following priority rules, stopping at the
+// first (most important) applicable one:
+//
+//   - Anything else comes before RC4
+//
+//     RC4 has practically exploitable biases. See https://www.rc4nomore.com.
+//
+//   - Anything else comes before CBC_SHA256
+//
+//     SHA-256 variants of the CBC ciphersuites don't implement any Lucky13
+//     countermeasures. See http://www.isg.rhul.ac.uk/tls/Lucky13.html and
+//     https://www.imperialviolet.org/2013/02/04/luckythirteen.html.
+//
+//   - Anything else comes before 3DES
+//
+//     3DES has 64-bit blocks, which makes it fundamentally susceptible to
+//     birthday attacks. See https://sweet32.info.
+//
+//   - ECDHE comes before anything else
+//
+//     Once we got the broken stuff out of the way, the most important
+//     property a cipher suite can have is forward secrecy. We don't
+//     implement FFDHE, so that means ECDHE.
+//
+//   - AEADs come before CBC ciphers
+//
+//     Even with Lucky13 countermeasures, MAC-then-Encrypt CBC cipher suites
+//     are fundamentally fragile, and suffered from an endless sequence of
+//     padding oracle attacks. See https://eprint.iacr.org/2015/1129,
+//     https://www.imperialviolet.org/2014/12/08/poodleagain.html, and
+//     https://blog.cloudflare.com/yet-another-padding-oracle-in-openssl-cbc-ciphersuites/.
+//
+//   - AES comes before ChaCha20
+//
+//     When AES hardware is available, AES-128-GCM and AES-256-GCM are faster
+//     than ChaCha20Poly1305.
+//
+//     When AES hardware is not available, AES-128-GCM is one or more of: much
+//     slower, way more complex, and less safe (because not constant time)
+//     than ChaCha20Poly1305.
+//
+//     We use this list if we think both peers have AES hardware, and
+//     cipherSuitesPreferenceOrderNoAES otherwise.
+//
+//   - AES-128 comes before AES-256
+//
+//     The only potential advantages of AES-256 are better multi-target
+//     margins, and hypothetical post-quantum properties. Neither apply to
+//     TLS, and AES-256 is slower due to its four extra rounds (which don't
+//     contribute to the advantages above).
+//
+//   - ECDSA comes before RSA
+//
+//     The relative order of ECDSA and RSA cipher suites doesn't matter,
+//     as they depend on the certificate. Pick one to get a stable order.
+var cipherSuitesPreferenceOrder = []uint16{
+	// AEADs w/ ECDHE
+	TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256, TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
+	TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384, TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
+	TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305, TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305,
+
+	// CBC w/ ECDHE
+	TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA, TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
+	TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA, TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
+
+	// AEADs w/o ECDHE
+	TLS_RSA_WITH_AES_128_GCM_SHA256,
+	TLS_RSA_WITH_AES_256_GCM_SHA384,
+
+	// CBC w/o ECDHE
+	TLS_RSA_WITH_AES_128_CBC_SHA,
+	TLS_RSA_WITH_AES_256_CBC_SHA,
+
+	// 3DES
+	TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA,
+	TLS_RSA_WITH_3DES_EDE_CBC_SHA,
+
+	// CBC_SHA256
+	TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256, TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256,
+	TLS_RSA_WITH_AES_128_CBC_SHA256,
+
+	// RC4
+	TLS_ECDHE_ECDSA_WITH_RC4_128_SHA, TLS_ECDHE_RSA_WITH_RC4_128_SHA,
+	TLS_RSA_WITH_RC4_128_SHA,
+}
+
+var cipherSuitesPreferenceOrderNoAES = []uint16{
+	// ChaCha20Poly1305
+	TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305, TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305,
+
+	// AES-GCM w/ ECDHE
+	TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256, TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
+	TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384, TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
+
+	// The rest of cipherSuitesPreferenceOrder.
+	TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA, TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
+	TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA, TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
+	TLS_RSA_WITH_AES_128_GCM_SHA256,
+	TLS_RSA_WITH_AES_256_GCM_SHA384,
+	TLS_RSA_WITH_AES_128_CBC_SHA,
+	TLS_RSA_WITH_AES_256_CBC_SHA,
+	TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA,
+	TLS_RSA_WITH_3DES_EDE_CBC_SHA,
+	TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256, TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256,
+	TLS_RSA_WITH_AES_128_CBC_SHA256,
+	TLS_ECDHE_ECDSA_WITH_RC4_128_SHA, TLS_ECDHE_RSA_WITH_RC4_128_SHA,
+	TLS_RSA_WITH_RC4_128_SHA,
+}
+
+// disabledCipherSuites are not used unless explicitly listed in
+// Config.CipherSuites. They MUST be at the end of cipherSuitesPreferenceOrder.
+var disabledCipherSuites = []uint16{
+	// CBC_SHA256
+	TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256, TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256,
+	TLS_RSA_WITH_AES_128_CBC_SHA256,
+
+	// RC4
+	TLS_ECDHE_ECDSA_WITH_RC4_128_SHA, TLS_ECDHE_RSA_WITH_RC4_128_SHA,
+	TLS_RSA_WITH_RC4_128_SHA,
+}
+
+var (
+	defaultCipherSuitesLen = len(cipherSuitesPreferenceOrder) - len(disabledCipherSuites)
+	defaultCipherSuites    = cipherSuitesPreferenceOrder[:defaultCipherSuitesLen]
+)
+
+// defaultCipherSuitesTLS13 is also the preference order, since there are no
+// disabled by default TLS 1.3 cipher suites. The same AES vs ChaCha20 logic as
+// cipherSuitesPreferenceOrder applies.
+var defaultCipherSuitesTLS13 = []uint16{
+	TLS_AES_128_GCM_SHA256,
+	TLS_AES_256_GCM_SHA384,
+	TLS_CHACHA20_POLY1305_SHA256,
+}
+
+var defaultCipherSuitesTLS13NoAES = []uint16{
+	TLS_CHACHA20_POLY1305_SHA256,
+	TLS_AES_128_GCM_SHA256,
+	TLS_AES_256_GCM_SHA384,
+}
+
+var (
+	hasGCMAsmAMD64 = cpu.X86.HasAES && cpu.X86.HasPCLMULQDQ
+	hasGCMAsmARM64 = cpu.ARM64.HasAES && cpu.ARM64.HasPMULL
+	// Keep in sync with crypto/aes/cipher_s390x.go.
+	hasGCMAsmS390X = cpu.S390X.HasAES && cpu.S390X.HasAESCBC && cpu.S390X.HasAESCTR &&
+		(cpu.S390X.HasGHASH || cpu.S390X.HasAESGCM)
+
+	hasAESGCMHardwareSupport = runtime.GOARCH == "amd64" && hasGCMAsmAMD64 ||
+		runtime.GOARCH == "arm64" && hasGCMAsmARM64 ||
+		runtime.GOARCH == "s390x" && hasGCMAsmS390X
+)
+
+var aesgcmCiphers = map[uint16]bool{
+	// TLS 1.2
+	TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256:   true,
+	TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384:   true,
+	TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256: true,
+	TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384: true,
+	// TLS 1.3
+	TLS_AES_128_GCM_SHA256: true,
+	TLS_AES_256_GCM_SHA384: true,
+}
+
+var nonAESGCMAEADCiphers = map[uint16]bool{
+	// TLS 1.2
+	TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305:   true,
+	TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305: true,
+	// TLS 1.3
+	TLS_CHACHA20_POLY1305_SHA256: true,
+}
+
+// aesgcmPreferred returns whether the first known cipher in the preference list
+// is an AES-GCM cipher, implying the peer has hardware support for it.
+func aesgcmPreferred(ciphers []uint16) bool {
+	for _, cID := range ciphers {
+		if c := cipherSuiteByID(cID); c != nil {
+			return aesgcmCiphers[cID]
+		}
+		if c := cipherSuiteTLS13ByID(cID); c != nil {
+			return aesgcmCiphers[cID]
+		}
+	}
+	return false
+}
+
+func cipherRC4(key, iv []byte, isRead bool) any {
+	cipher, _ := rc4.NewCipher(key)
+	return cipher
+}
+
+func cipher3DES(key, iv []byte, isRead bool) any {
+	block, _ := des.NewTripleDESCipher(key)
+	if isRead {
+		return cipher.NewCBCDecrypter(block, iv)
+	}
+	return cipher.NewCBCEncrypter(block, iv)
+}
+
+func cipherAES(key, iv []byte, isRead bool) any {
+	block, _ := aes.NewCipher(key)
+	if isRead {
+		return cipher.NewCBCDecrypter(block, iv)
+	}
+	return cipher.NewCBCEncrypter(block, iv)
+}
+
+// macSHA1 returns a SHA-1 based constant time MAC.
+func macSHA1(key []byte) hash.Hash {
+	h := sha1.New
+	// The BoringCrypto SHA1 does not have a constant-time
+	// checksum function, so don't try to use it.
+	if !boring.Enabled {
+		h = newConstantTimeHash(h)
+	}
+	return hmac.New(h, key)
+}
+
+// macSHA256 returns a SHA-256 based MAC. This is only supported in TLS 1.2 and
+// is currently only used in disabled-by-default cipher suites.
+func macSHA256(key []byte) hash.Hash {
+	return hmac.New(sha256.New, key)
+}
+
+type aead interface {
+	cipher.AEAD
+
+	// explicitNonceLen returns the number of bytes of explicit nonce
+	// included in each record. This is eight for older AEADs and
+	// zero for modern ones.
+	explicitNonceLen() int
+}
+
+const (
+	aeadNonceLength   = 12
+	noncePrefixLength = 4
+)
+
+// prefixNonceAEAD wraps an AEAD and prefixes a fixed portion of the nonce to
+// each call.
+type prefixNonceAEAD struct {
+	// nonce contains the fixed part of the nonce in the first four bytes.
+	nonce [aeadNonceLength]byte
+	aead  cipher.AEAD
+}
+
+func (f *prefixNonceAEAD) NonceSize() int        { return aeadNonceLength - noncePrefixLength }
+func (f *prefixNonceAEAD) Overhead() int         { return f.aead.Overhead() }
+func (f *prefixNonceAEAD) explicitNonceLen() int { return f.NonceSize() }
+
+func (f *prefixNonceAEAD) Seal(out, nonce, plaintext, additionalData []byte) []byte {
+	copy(f.nonce[4:], nonce)
+	return f.aead.Seal(out, f.nonce[:], plaintext, additionalData)
+}
+
+func (f *prefixNonceAEAD) Open(out, nonce, ciphertext, additionalData []byte) ([]byte, error) {
+	copy(f.nonce[4:], nonce)
+	return f.aead.Open(out, f.nonce[:], ciphertext, additionalData)
+}
+
+// xoredNonceAEAD wraps an AEAD by XORing in a fixed pattern to the nonce
+// before each call.
+type xorNonceAEAD struct {
+	nonceMask [aeadNonceLength]byte
+	aead      cipher.AEAD
+}
+
+func (f *xorNonceAEAD) NonceSize() int        { return 8 } // 64-bit sequence number
+func (f *xorNonceAEAD) Overhead() int         { return f.aead.Overhead() }
+func (f *xorNonceAEAD) explicitNonceLen() int { return 0 }
+
+func (f *xorNonceAEAD) Seal(out, nonce, plaintext, additionalData []byte) []byte {
+	for i, b := range nonce {
+		f.nonceMask[4+i] ^= b
+	}
+	result := f.aead.Seal(out, f.nonceMask[:], plaintext, additionalData)
+	for i, b := range nonce {
+		f.nonceMask[4+i] ^= b
+	}
+
+	return result
+}
+
+func (f *xorNonceAEAD) Open(out, nonce, ciphertext, additionalData []byte) ([]byte, error) {
+	for i, b := range nonce {
+		f.nonceMask[4+i] ^= b
+	}
+	result, err := f.aead.Open(out, f.nonceMask[:], ciphertext, additionalData)
+	for i, b := range nonce {
+		f.nonceMask[4+i] ^= b
+	}
+
+	return result, err
+}
+
+func aeadAESGCM(key, noncePrefix []byte) aead {
+	if len(noncePrefix) != noncePrefixLength {
+		panic("tls: internal error: wrong nonce length")
+	}
+	aes, err := aes.NewCipher(key)
+	if err != nil {
+		panic(err)
+	}
+	var aead cipher.AEAD
+	if boring.Enabled {
+		aead, err = boring.NewGCMTLS(aes)
+	} else {
+		boring.Unreachable()
+		aead, err = cipher.NewGCM(aes)
+	}
+	if err != nil {
+		panic(err)
+	}
+
+	ret := &prefixNonceAEAD{aead: aead}
+	copy(ret.nonce[:], noncePrefix)
+	return ret
+}
+
+func aeadAESGCMTLS13(key, nonceMask []byte) aead {
+	if len(nonceMask) != aeadNonceLength {
+		panic("tls: internal error: wrong nonce length")
+	}
+	aes, err := aes.NewCipher(key)
+	if err != nil {
+		panic(err)
+	}
+	aead, err := cipher.NewGCM(aes)
+	if err != nil {
+		panic(err)
+	}
+
+	ret := &xorNonceAEAD{aead: aead}
+	copy(ret.nonceMask[:], nonceMask)
+	return ret
+}
+
+func aeadChaCha20Poly1305(key, nonceMask []byte) aead {
+	if len(nonceMask) != aeadNonceLength {
+		panic("tls: internal error: wrong nonce length")
+	}
+	aead, err := chacha20poly1305.New(key)
+	if err != nil {
+		panic(err)
+	}
+
+	ret := &xorNonceAEAD{aead: aead}
+	copy(ret.nonceMask[:], nonceMask)
+	return ret
+}
+
+type constantTimeHash interface {
+	hash.Hash
+	ConstantTimeSum(b []byte) []byte
+}
+
+// cthWrapper wraps any hash.Hash that implements ConstantTimeSum, and replaces
+// with that all calls to Sum. It's used to obtain a ConstantTimeSum-based HMAC.
+type cthWrapper struct {
+	h constantTimeHash
+}
+
+func (c *cthWrapper) Size() int                   { return c.h.Size() }
+func (c *cthWrapper) BlockSize() int              { return c.h.BlockSize() }
+func (c *cthWrapper) Reset()                      { c.h.Reset() }
+func (c *cthWrapper) Write(p []byte) (int, error) { return c.h.Write(p) }
+func (c *cthWrapper) Sum(b []byte) []byte         { return c.h.ConstantTimeSum(b) }
+
+func newConstantTimeHash(h func() hash.Hash) func() hash.Hash {
+	boring.Unreachable()
+	return func() hash.Hash {
+		return &cthWrapper{h().(constantTimeHash)}
+	}
+}
+
+// tls10MAC implements the TLS 1.0 MAC function. RFC 2246, Section 6.2.3.
+func tls10MAC(h hash.Hash, out, seq, header, data, extra []byte) []byte {
+	h.Reset()
+	h.Write(seq)
+	h.Write(header)
+	h.Write(data)
+	res := h.Sum(out)
+	if extra != nil {
+		h.Write(extra)
+	}
+	return res
+}
+
+func rsaKA(version uint16) keyAgreement {
+	return rsaKeyAgreement{}
+}
+
+func ecdheECDSAKA(version uint16) keyAgreement {
+	return &ecdheKeyAgreement{
+		isRSA:   false,
+		version: version,
+	}
+}
+
+func ecdheRSAKA(version uint16) keyAgreement {
+	return &ecdheKeyAgreement{
+		isRSA:   true,
+		version: version,
+	}
+}
+
+// mutualCipherSuite returns a cipherSuite given a list of supported
+// ciphersuites and the id requested by the peer.
+func mutualCipherSuite(have []uint16, want uint16) *cipherSuite {
+	for _, id := range have {
+		if id == want {
+			return cipherSuiteByID(id)
+		}
+	}
+	return nil
+}
+
+func cipherSuiteByID(id uint16) *cipherSuite {
+	for _, cipherSuite := range cipherSuites {
+		if cipherSuite.id == id {
+			return cipherSuite
+		}
+	}
+	return nil
+}
+
+func mutualCipherSuiteTLS13(have []uint16, want uint16) *cipherSuiteTLS13 {
+	for _, id := range have {
+		if id == want {
+			return cipherSuiteTLS13ByID(id)
+		}
+	}
+	return nil
+}
+
+func cipherSuiteTLS13ByID(id uint16) *cipherSuiteTLS13 {
+	for _, cipherSuite := range cipherSuitesTLS13 {
+		if cipherSuite.id == id {
+			return cipherSuite
+		}
+	}
+	return nil
+}
+
+// A list of cipher suite IDs that are, or have been, implemented by this
+// package.
+//
+// See https://www.iana.org/assignments/tls-parameters/tls-parameters.xml
+const (
+	// TLS 1.0 - 1.2 cipher suites.
+	TLS_RSA_WITH_RC4_128_SHA                      uint16 = 0x0005
+	TLS_RSA_WITH_3DES_EDE_CBC_SHA                 uint16 = 0x000a
+	TLS_RSA_WITH_AES_128_CBC_SHA                  uint16 = 0x002f
+	TLS_RSA_WITH_AES_256_CBC_SHA                  uint16 = 0x0035
+	TLS_RSA_WITH_AES_128_CBC_SHA256               uint16 = 0x003c
+	TLS_RSA_WITH_AES_128_GCM_SHA256               uint16 = 0x009c
+	TLS_RSA_WITH_AES_256_GCM_SHA384               uint16 = 0x009d
+	TLS_ECDHE_ECDSA_WITH_RC4_128_SHA              uint16 = 0xc007
+	TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA          uint16 = 0xc009
+	TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA          uint16 = 0xc00a
+	TLS_ECDHE_RSA_WITH_RC4_128_SHA                uint16 = 0xc011
+	TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA           uint16 = 0xc012
+	TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA            uint16 = 0xc013
+	TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA            uint16 = 0xc014
+	TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256       uint16 = 0xc023
+	TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256         uint16 = 0xc027
+	TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256         uint16 = 0xc02f
+	TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256       uint16 = 0xc02b
+	TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384         uint16 = 0xc030
+	TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384       uint16 = 0xc02c
+	TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256   uint16 = 0xcca8
+	TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 uint16 = 0xcca9
+
+	// TLS 1.3 cipher suites.
+	TLS_AES_128_GCM_SHA256       uint16 = 0x1301
+	TLS_AES_256_GCM_SHA384       uint16 = 0x1302
+	TLS_CHACHA20_POLY1305_SHA256 uint16 = 0x1303
+
+	// TLS_FALLBACK_SCSV isn't a standard cipher suite but an indicator
+	// that the client is doing version fallback. See RFC 7507.
+	TLS_FALLBACK_SCSV uint16 = 0x5600
+
+	// Legacy names for the corresponding cipher suites with the correct _SHA256
+	// suffix, retained for backward compatibility.
+	TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305   = TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256
+	TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305 = TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256
+)
diff --git a/contrib/go/_std_1.19/src/crypto/tls/common.go b/contrib/go/_std_1.19/src/crypto/tls/common.go
new file mode 100644
index 0000000000..1861efce66
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/tls/common.go
@@ -0,0 +1,1485 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package tls
+
+import (
+	"bytes"
+	"container/list"
+	"context"
+	"crypto"
+	"crypto/ecdsa"
+	"crypto/ed25519"
+	"crypto/elliptic"
+	"crypto/rand"
+	"crypto/rsa"
+	"crypto/sha512"
+	"crypto/x509"
+	"errors"
+	"fmt"
+	"io"
+	"net"
+	"strings"
+	"sync"
+	"time"
+)
+
+const (
+	VersionTLS10 = 0x0301
+	VersionTLS11 = 0x0302
+	VersionTLS12 = 0x0303
+	VersionTLS13 = 0x0304
+
+	// Deprecated: SSLv3 is cryptographically broken, and is no longer
+	// supported by this package. See golang.org/issue/32716.
+	VersionSSL30 = 0x0300
+)
+
+const (
+	maxPlaintext       = 16384        // maximum plaintext payload length
+	maxCiphertext      = 16384 + 2048 // maximum ciphertext payload length
+	maxCiphertextTLS13 = 16384 + 256  // maximum ciphertext length in TLS 1.3
+	recordHeaderLen    = 5            // record header length
+	maxHandshake       = 65536        // maximum handshake we support (protocol max is 16 MB)
+	maxUselessRecords  = 16           // maximum number of consecutive non-advancing records
+)
+
+// TLS record types.
+type recordType uint8
+
+const (
+	recordTypeChangeCipherSpec recordType = 20
+	recordTypeAlert            recordType = 21
+	recordTypeHandshake        recordType = 22
+	recordTypeApplicationData  recordType = 23
+)
+
+// TLS handshake message types.
+const (
+	typeHelloRequest        uint8 = 0
+	typeClientHello         uint8 = 1
+	typeServerHello         uint8 = 2
+	typeNewSessionTicket    uint8 = 4
+	typeEndOfEarlyData      uint8 = 5
+	typeEncryptedExtensions uint8 = 8
+	typeCertificate         uint8 = 11
+	typeServerKeyExchange   uint8 = 12
+	typeCertificateRequest  uint8 = 13
+	typeServerHelloDone     uint8 = 14
+	typeCertificateVerify   uint8 = 15
+	typeClientKeyExchange   uint8 = 16
+	typeFinished            uint8 = 20
+	typeCertificateStatus   uint8 = 22
+	typeKeyUpdate           uint8 = 24
+	typeNextProtocol        uint8 = 67  // Not IANA assigned
+	typeMessageHash         uint8 = 254 // synthetic message
+)
+
+// TLS compression types.
+const (
+	compressionNone uint8 = 0
+)
+
+// TLS extension numbers
+const (
+	extensionServerName              uint16 = 0
+	extensionStatusRequest           uint16 = 5
+	extensionSupportedCurves         uint16 = 10 // supported_groups in TLS 1.3, see RFC 8446, Section 4.2.7
+	extensionSupportedPoints         uint16 = 11
+	extensionSignatureAlgorithms     uint16 = 13
+	extensionALPN                    uint16 = 16
+	extensionSCT                     uint16 = 18
+	extensionSessionTicket           uint16 = 35
+	extensionPreSharedKey            uint16 = 41
+	extensionEarlyData               uint16 = 42
+	extensionSupportedVersions       uint16 = 43
+	extensionCookie                  uint16 = 44
+	extensionPSKModes                uint16 = 45
+	extensionCertificateAuthorities  uint16 = 47
+	extensionSignatureAlgorithmsCert uint16 = 50
+	extensionKeyShare                uint16 = 51
+	extensionRenegotiationInfo       uint16 = 0xff01
+)
+
+// TLS signaling cipher suite values
+const (
+	scsvRenegotiation uint16 = 0x00ff
+)
+
+// CurveID is the type of a TLS identifier for an elliptic curve. See
+// https://www.iana.org/assignments/tls-parameters/tls-parameters.xml#tls-parameters-8.
+//
+// In TLS 1.3, this type is called NamedGroup, but at this time this library
+// only supports Elliptic Curve based groups. See RFC 8446, Section 4.2.7.
+type CurveID uint16
+
+const (
+	CurveP256 CurveID = 23
+	CurveP384 CurveID = 24
+	CurveP521 CurveID = 25
+	X25519    CurveID = 29
+)
+
+// TLS 1.3 Key Share. See RFC 8446, Section 4.2.8.
+type keyShare struct {
+	group CurveID
+	data  []byte
+}
+
+// TLS 1.3 PSK Key Exchange Modes. See RFC 8446, Section 4.2.9.
+const (
+	pskModePlain uint8 = 0
+	pskModeDHE   uint8 = 1
+)
+
+// TLS 1.3 PSK Identity. Can be a Session Ticket, or a reference to a saved
+// session. See RFC 8446, Section 4.2.11.
+type pskIdentity struct {
+	label               []byte
+	obfuscatedTicketAge uint32
+}
+
+// TLS Elliptic Curve Point Formats
+// https://www.iana.org/assignments/tls-parameters/tls-parameters.xml#tls-parameters-9
+const (
+	pointFormatUncompressed uint8 = 0
+)
+
+// TLS CertificateStatusType (RFC 3546)
+const (
+	statusTypeOCSP uint8 = 1
+)
+
+// Certificate types (for certificateRequestMsg)
+const (
+	certTypeRSASign   = 1
+	certTypeECDSASign = 64 // ECDSA or EdDSA keys, see RFC 8422, Section 3.
+)
+
+// Signature algorithms (for internal signaling use). Starting at 225 to avoid overlap with
+// TLS 1.2 codepoints (RFC 5246, Appendix A.4.1), with which these have nothing to do.
+const (
+	signaturePKCS1v15 uint8 = iota + 225
+	signatureRSAPSS
+	signatureECDSA
+	signatureEd25519
+)
+
+// directSigning is a standard Hash value that signals that no pre-hashing
+// should be performed, and that the input should be signed directly. It is the
+// hash function associated with the Ed25519 signature scheme.
+var directSigning crypto.Hash = 0
+
+// defaultSupportedSignatureAlgorithms contains the signature and hash algorithms that
+// the code advertises as supported in a TLS 1.2+ ClientHello and in a TLS 1.2+
+// CertificateRequest. The two fields are merged to match with TLS 1.3.
+// Note that in TLS 1.2, the ECDSA algorithms are not constrained to P-256, etc.
+var defaultSupportedSignatureAlgorithms = []SignatureScheme{
+	PSSWithSHA256,
+	ECDSAWithP256AndSHA256,
+	Ed25519,
+	PSSWithSHA384,
+	PSSWithSHA512,
+	PKCS1WithSHA256,
+	PKCS1WithSHA384,
+	PKCS1WithSHA512,
+	ECDSAWithP384AndSHA384,
+	ECDSAWithP521AndSHA512,
+	PKCS1WithSHA1,
+	ECDSAWithSHA1,
+}
+
+// helloRetryRequestRandom is set as the Random value of a ServerHello
+// to signal that the message is actually a HelloRetryRequest.
+var helloRetryRequestRandom = []byte{ // See RFC 8446, Section 4.1.3.
+	0xCF, 0x21, 0xAD, 0x74, 0xE5, 0x9A, 0x61, 0x11,
+	0xBE, 0x1D, 0x8C, 0x02, 0x1E, 0x65, 0xB8, 0x91,
+	0xC2, 0xA2, 0x11, 0x16, 0x7A, 0xBB, 0x8C, 0x5E,
+	0x07, 0x9E, 0x09, 0xE2, 0xC8, 0xA8, 0x33, 0x9C,
+}
+
+const (
+	// downgradeCanaryTLS12 or downgradeCanaryTLS11 is embedded in the server
+	// random as a downgrade protection if the server would be capable of
+	// negotiating a higher version. See RFC 8446, Section 4.1.3.
+	downgradeCanaryTLS12 = "DOWNGRD\x01"
+	downgradeCanaryTLS11 = "DOWNGRD\x00"
+)
+
+// testingOnlyForceDowngradeCanary is set in tests to force the server side to
+// include downgrade canaries even if it's using its highers supported version.
+var testingOnlyForceDowngradeCanary bool
+
+// ConnectionState records basic TLS details about the connection.
+type ConnectionState struct {
+	// Version is the TLS version used by the connection (e.g. VersionTLS12).
+	Version uint16
+
+	// HandshakeComplete is true if the handshake has concluded.
+	HandshakeComplete bool
+
+	// DidResume is true if this connection was successfully resumed from a
+	// previous session with a session ticket or similar mechanism.
+	DidResume bool
+
+	// CipherSuite is the cipher suite negotiated for the connection (e.g.
+	// TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256, TLS_AES_128_GCM_SHA256).
+	CipherSuite uint16
+
+	// NegotiatedProtocol is the application protocol negotiated with ALPN.
+	NegotiatedProtocol string
+
+	// NegotiatedProtocolIsMutual used to indicate a mutual NPN negotiation.
+	//
+	// Deprecated: this value is always true.
+	NegotiatedProtocolIsMutual bool
+
+	// ServerName is the value of the Server Name Indication extension sent by
+	// the client. It's available both on the server and on the client side.
+	ServerName string
+
+	// PeerCertificates are the parsed certificates sent by the peer, in the
+	// order in which they were sent. The first element is the leaf certificate
+	// that the connection is verified against.
+	//
+	// On the client side, it can't be empty. On the server side, it can be
+	// empty if Config.ClientAuth is not RequireAnyClientCert or
+	// RequireAndVerifyClientCert.
+	PeerCertificates []*x509.Certificate
+
+	// VerifiedChains is a list of one or more chains where the first element is
+	// PeerCertificates[0] and the last element is from Config.RootCAs (on the
+	// client side) or Config.ClientCAs (on the server side).
+	//
+	// On the client side, it's set if Config.InsecureSkipVerify is false. On
+	// the server side, it's set if Config.ClientAuth is VerifyClientCertIfGiven
+	// (and the peer provided a certificate) or RequireAndVerifyClientCert.
+	VerifiedChains [][]*x509.Certificate
+
+	// SignedCertificateTimestamps is a list of SCTs provided by the peer
+	// through the TLS handshake for the leaf certificate, if any.
+	SignedCertificateTimestamps [][]byte
+
+	// OCSPResponse is a stapled Online Certificate Status Protocol (OCSP)
+	// response provided by the peer for the leaf certificate, if any.
+	OCSPResponse []byte
+
+	// TLSUnique contains the "tls-unique" channel binding value (see RFC 5929,
+	// Section 3). This value will be nil for TLS 1.3 connections and for all
+	// resumed connections.
+	//
+	// Deprecated: there are conditions in which this value might not be unique
+	// to a connection. See the Security Considerations sections of RFC 5705 and
+	// RFC 7627, and https://mitls.org/pages/attacks/3SHAKE#channelbindings.
+	TLSUnique []byte
+
+	// ekm is a closure exposed via ExportKeyingMaterial.
+	ekm func(label string, context []byte, length int) ([]byte, error)
+}
+
+// ExportKeyingMaterial returns length bytes of exported key material in a new
+// slice as defined in RFC 5705. If context is nil, it is not used as part of
+// the seed. If the connection was set to allow renegotiation via
+// Config.Renegotiation, this function will return an error.
+func (cs *ConnectionState) ExportKeyingMaterial(label string, context []byte, length int) ([]byte, error) {
+	return cs.ekm(label, context, length)
+}
+
+// ClientAuthType declares the policy the server will follow for
+// TLS Client Authentication.
+type ClientAuthType int
+
+const (
+	// NoClientCert indicates that no client certificate should be requested
+	// during the handshake, and if any certificates are sent they will not
+	// be verified.
+	NoClientCert ClientAuthType = iota
+	// RequestClientCert indicates that a client certificate should be requested
+	// during the handshake, but does not require that the client send any
+	// certificates.
+	RequestClientCert
+	// RequireAnyClientCert indicates that a client certificate should be requested
+	// during the handshake, and that at least one certificate is required to be
+	// sent by the client, but that certificate is not required to be valid.
+	RequireAnyClientCert
+	// VerifyClientCertIfGiven indicates that a client certificate should be requested
+	// during the handshake, but does not require that the client sends a
+	// certificate. If the client does send a certificate it is required to be
+	// valid.
+	VerifyClientCertIfGiven
+	// RequireAndVerifyClientCert indicates that a client certificate should be requested
+	// during the handshake, and that at least one valid certificate is required
+	// to be sent by the client.
+	RequireAndVerifyClientCert
+)
+
+// requiresClientCert reports whether the ClientAuthType requires a client
+// certificate to be provided.
+func requiresClientCert(c ClientAuthType) bool {
+	switch c {
+	case RequireAnyClientCert, RequireAndVerifyClientCert:
+		return true
+	default:
+		return false
+	}
+}
+
+// ClientSessionState contains the state needed by clients to resume TLS
+// sessions.
+type ClientSessionState struct {
+	sessionTicket      []uint8               // Encrypted ticket used for session resumption with server
+	vers               uint16                // TLS version negotiated for the session
+	cipherSuite        uint16                // Ciphersuite negotiated for the session
+	masterSecret       []byte                // Full handshake MasterSecret, or TLS 1.3 resumption_master_secret
+	serverCertificates []*x509.Certificate   // Certificate chain presented by the server
+	verifiedChains     [][]*x509.Certificate // Certificate chains we built for verification
+	receivedAt         time.Time             // When the session ticket was received from the server
+	ocspResponse       []byte                // Stapled OCSP response presented by the server
+	scts               [][]byte              // SCTs presented by the server
+
+	// TLS 1.3 fields.
+	nonce  []byte    // Ticket nonce sent by the server, to derive PSK
+	useBy  time.Time // Expiration of the ticket lifetime as set by the server
+	ageAdd uint32    // Random obfuscation factor for sending the ticket age
+}
+
+// ClientSessionCache is a cache of ClientSessionState objects that can be used
+// by a client to resume a TLS session with a given server. ClientSessionCache
+// implementations should expect to be called concurrently from different
+// goroutines. Up to TLS 1.2, only ticket-based resumption is supported, not
+// SessionID-based resumption. In TLS 1.3 they were merged into PSK modes, which
+// are supported via this interface.
+type ClientSessionCache interface {
+	// Get searches for a ClientSessionState associated with the given key.
+	// On return, ok is true if one was found.
+	Get(sessionKey string) (session *ClientSessionState, ok bool)
+
+	// Put adds the ClientSessionState to the cache with the given key. It might
+	// get called multiple times in a connection if a TLS 1.3 server provides
+	// more than one session ticket. If called with a nil *ClientSessionState,
+	// it should remove the cache entry.
+	Put(sessionKey string, cs *ClientSessionState)
+}
+
+//go:generate stringer -type=SignatureScheme,CurveID,ClientAuthType -output=common_string.go
+
+// SignatureScheme identifies a signature algorithm supported by TLS. See
+// RFC 8446, Section 4.2.3.
+type SignatureScheme uint16
+
+const (
+	// RSASSA-PKCS1-v1_5 algorithms.
+	PKCS1WithSHA256 SignatureScheme = 0x0401
+	PKCS1WithSHA384 SignatureScheme = 0x0501
+	PKCS1WithSHA512 SignatureScheme = 0x0601
+
+	// RSASSA-PSS algorithms with public key OID rsaEncryption.
+	PSSWithSHA256 SignatureScheme = 0x0804
+	PSSWithSHA384 SignatureScheme = 0x0805
+	PSSWithSHA512 SignatureScheme = 0x0806
+
+	// ECDSA algorithms. Only constrained to a specific curve in TLS 1.3.
+	ECDSAWithP256AndSHA256 SignatureScheme = 0x0403
+	ECDSAWithP384AndSHA384 SignatureScheme = 0x0503
+	ECDSAWithP521AndSHA512 SignatureScheme = 0x0603
+
+	// EdDSA algorithms.
+	Ed25519 SignatureScheme = 0x0807
+
+	// Legacy signature and hash algorithms for TLS 1.2.
+	PKCS1WithSHA1 SignatureScheme = 0x0201
+	ECDSAWithSHA1 SignatureScheme = 0x0203
+)
+
+// ClientHelloInfo contains information from a ClientHello message in order to
+// guide application logic in the GetCertificate and GetConfigForClient callbacks.
+type ClientHelloInfo struct {
+	// CipherSuites lists the CipherSuites supported by the client (e.g.
+	// TLS_AES_128_GCM_SHA256, TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256).
+	CipherSuites []uint16
+
+	// ServerName indicates the name of the server requested by the client
+	// in order to support virtual hosting. ServerName is only set if the
+	// client is using SNI (see RFC 4366, Section 3.1).
+	ServerName string
+
+	// SupportedCurves lists the elliptic curves supported by the client.
+	// SupportedCurves is set only if the Supported Elliptic Curves
+	// Extension is being used (see RFC 4492, Section 5.1.1).
+	SupportedCurves []CurveID
+
+	// SupportedPoints lists the point formats supported by the client.
+	// SupportedPoints is set only if the Supported Point Formats Extension
+	// is being used (see RFC 4492, Section 5.1.2).
+	SupportedPoints []uint8
+
+	// SignatureSchemes lists the signature and hash schemes that the client
+	// is willing to verify. SignatureSchemes is set only if the Signature
+	// Algorithms Extension is being used (see RFC 5246, Section 7.4.1.4.1).
+	SignatureSchemes []SignatureScheme
+
+	// SupportedProtos lists the application protocols supported by the client.
+	// SupportedProtos is set only if the Application-Layer Protocol
+	// Negotiation Extension is being used (see RFC 7301, Section 3.1).
+	//
+	// Servers can select a protocol by setting Config.NextProtos in a
+	// GetConfigForClient return value.
+	SupportedProtos []string
+
+	// SupportedVersions lists the TLS versions supported by the client.
+	// For TLS versions less than 1.3, this is extrapolated from the max
+	// version advertised by the client, so values other than the greatest
+	// might be rejected if used.
+	SupportedVersions []uint16
+
+	// Conn is the underlying net.Conn for the connection. Do not read
+	// from, or write to, this connection; that will cause the TLS
+	// connection to fail.
+	Conn net.Conn
+
+	// config is embedded by the GetCertificate or GetConfigForClient caller,
+	// for use with SupportsCertificate.
+	config *Config
+
+	// ctx is the context of the handshake that is in progress.
+	ctx context.Context
+}
+
+// Context returns the context of the handshake that is in progress.
+// This context is a child of the context passed to HandshakeContext,
+// if any, and is canceled when the handshake concludes.
+func (c *ClientHelloInfo) Context() context.Context {
+	return c.ctx
+}
+
+// CertificateRequestInfo contains information from a server's
+// CertificateRequest message, which is used to demand a certificate and proof
+// of control from a client.
+type CertificateRequestInfo struct {
+	// AcceptableCAs contains zero or more, DER-encoded, X.501
+	// Distinguished Names. These are the names of root or intermediate CAs
+	// that the server wishes the returned certificate to be signed by. An
+	// empty slice indicates that the server has no preference.
+	AcceptableCAs [][]byte
+
+	// SignatureSchemes lists the signature schemes that the server is
+	// willing to verify.
+	SignatureSchemes []SignatureScheme
+
+	// Version is the TLS version that was negotiated for this connection.
+	Version uint16
+
+	// ctx is the context of the handshake that is in progress.
+	ctx context.Context
+}
+
+// Context returns the context of the handshake that is in progress.
+// This context is a child of the context passed to HandshakeContext,
+// if any, and is canceled when the handshake concludes.
+func (c *CertificateRequestInfo) Context() context.Context {
+	return c.ctx
+}
+
+// RenegotiationSupport enumerates the different levels of support for TLS
+// renegotiation. TLS renegotiation is the act of performing subsequent
+// handshakes on a connection after the first. This significantly complicates
+// the state machine and has been the source of numerous, subtle security
+// issues. Initiating a renegotiation is not supported, but support for
+// accepting renegotiation requests may be enabled.
+//
+// Even when enabled, the server may not change its identity between handshakes
+// (i.e. the leaf certificate must be the same). Additionally, concurrent
+// handshake and application data flow is not permitted so renegotiation can
+// only be used with protocols that synchronise with the renegotiation, such as
+// HTTPS.
+//
+// Renegotiation is not defined in TLS 1.3.
+type RenegotiationSupport int
+
+const (
+	// RenegotiateNever disables renegotiation.
+	RenegotiateNever RenegotiationSupport = iota
+
+	// RenegotiateOnceAsClient allows a remote server to request
+	// renegotiation once per connection.
+	RenegotiateOnceAsClient
+
+	// RenegotiateFreelyAsClient allows a remote server to repeatedly
+	// request renegotiation.
+	RenegotiateFreelyAsClient
+)
+
+// A Config structure is used to configure a TLS client or server.
+// After one has been passed to a TLS function it must not be
+// modified. A Config may be reused; the tls package will also not
+// modify it.
+type Config struct {
+	// Rand provides the source of entropy for nonces and RSA blinding.
+	// If Rand is nil, TLS uses the cryptographic random reader in package
+	// crypto/rand.
+	// The Reader must be safe for use by multiple goroutines.
+	Rand io.Reader
+
+	// Time returns the current time as the number of seconds since the epoch.
+	// If Time is nil, TLS uses time.Now.
+	Time func() time.Time
+
+	// Certificates contains one or more certificate chains to present to the
+	// other side of the connection. The first certificate compatible with the
+	// peer's requirements is selected automatically.
+	//
+	// Server configurations must set one of Certificates, GetCertificate or
+	// GetConfigForClient. Clients doing client-authentication may set either
+	// Certificates or GetClientCertificate.
+	//
+	// Note: if there are multiple Certificates, and they don't have the
+	// optional field Leaf set, certificate selection will incur a significant
+	// per-handshake performance cost.
+	Certificates []Certificate
+
+	// NameToCertificate maps from a certificate name to an element of
+	// Certificates. Note that a certificate name can be of the form
+	// '*.example.com' and so doesn't have to be a domain name as such.
+	//
+	// Deprecated: NameToCertificate only allows associating a single
+	// certificate with a given name. Leave this field nil to let the library
+	// select the first compatible chain from Certificates.
+	NameToCertificate map[string]*Certificate
+
+	// GetCertificate returns a Certificate based on the given
+	// ClientHelloInfo. It will only be called if the client supplies SNI
+	// information or if Certificates is empty.
+	//
+	// If GetCertificate is nil or returns nil, then the certificate is
+	// retrieved from NameToCertificate. If NameToCertificate is nil, the
+	// best element of Certificates will be used.
+	GetCertificate func(*ClientHelloInfo) (*Certificate, error)
+
+	// GetClientCertificate, if not nil, is called when a server requests a
+	// certificate from a client. If set, the contents of Certificates will
+	// be ignored.
+	//
+	// If GetClientCertificate returns an error, the handshake will be
+	// aborted and that error will be returned. Otherwise
+	// GetClientCertificate must return a non-nil Certificate. If
+	// Certificate.Certificate is empty then no certificate will be sent to
+	// the server. If this is unacceptable to the server then it may abort
+	// the handshake.
+	//
+	// GetClientCertificate may be called multiple times for the same
+	// connection if renegotiation occurs or if TLS 1.3 is in use.
+	GetClientCertificate func(*CertificateRequestInfo) (*Certificate, error)
+
+	// GetConfigForClient, if not nil, is called after a ClientHello is
+	// received from a client. It may return a non-nil Config in order to
+	// change the Config that will be used to handle this connection. If
+	// the returned Config is nil, the original Config will be used. The
+	// Config returned by this callback may not be subsequently modified.
+	//
+	// If GetConfigForClient is nil, the Config passed to Server() will be
+	// used for all connections.
+	//
+	// If SessionTicketKey was explicitly set on the returned Config, or if
+	// SetSessionTicketKeys was called on the returned Config, those keys will
+	// be used. Otherwise, the original Config keys will be used (and possibly
+	// rotated if they are automatically managed).
+	GetConfigForClient func(*ClientHelloInfo) (*Config, error)
+
+	// VerifyPeerCertificate, if not nil, is called after normal
+	// certificate verification by either a TLS client or server. It
+	// receives the raw ASN.1 certificates provided by the peer and also
+	// any verified chains that normal processing found. If it returns a
+	// non-nil error, the handshake is aborted and that error results.
+	//
+	// If normal verification fails then the handshake will abort before
+	// considering this callback. If normal verification is disabled by
+	// setting InsecureSkipVerify, or (for a server) when ClientAuth is
+	// RequestClientCert or RequireAnyClientCert, then this callback will
+	// be considered but the verifiedChains argument will always be nil.
+	VerifyPeerCertificate func(rawCerts [][]byte, verifiedChains [][]*x509.Certificate) error
+
+	// VerifyConnection, if not nil, is called after normal certificate
+	// verification and after VerifyPeerCertificate by either a TLS client
+	// or server. If it returns a non-nil error, the handshake is aborted
+	// and that error results.
+	//
+	// If normal verification fails then the handshake will abort before
+	// considering this callback. This callback will run for all connections
+	// regardless of InsecureSkipVerify or ClientAuth settings.
+	VerifyConnection func(ConnectionState) error
+
+	// RootCAs defines the set of root certificate authorities
+	// that clients use when verifying server certificates.
+	// If RootCAs is nil, TLS uses the host's root CA set.
+	RootCAs *x509.CertPool
+
+	// NextProtos is a list of supported application level protocols, in
+	// order of preference. If both peers support ALPN, the selected
+	// protocol will be one from this list, and the connection will fail
+	// if there is no mutually supported protocol. If NextProtos is empty
+	// or the peer doesn't support ALPN, the connection will succeed and
+	// ConnectionState.NegotiatedProtocol will be empty.
+	NextProtos []string
+
+	// ServerName is used to verify the hostname on the returned
+	// certificates unless InsecureSkipVerify is given. It is also included
+	// in the client's handshake to support virtual hosting unless it is
+	// an IP address.
+	ServerName string
+
+	// ClientAuth determines the server's policy for
+	// TLS Client Authentication. The default is NoClientCert.
+	ClientAuth ClientAuthType
+
+	// ClientCAs defines the set of root certificate authorities
+	// that servers use if required to verify a client certificate
+	// by the policy in ClientAuth.
+	ClientCAs *x509.CertPool
+
+	// InsecureSkipVerify controls whether a client verifies the server's
+	// certificate chain and host name. If InsecureSkipVerify is true, crypto/tls
+	// accepts any certificate presented by the server and any host name in that
+	// certificate. In this mode, TLS is susceptible to machine-in-the-middle
+	// attacks unless custom verification is used. This should be used only for
+	// testing or in combination with VerifyConnection or VerifyPeerCertificate.
+	InsecureSkipVerify bool
+
+	// CipherSuites is a list of enabled TLS 1.0–1.2 cipher suites. The order of
+	// the list is ignored. Note that TLS 1.3 ciphersuites are not configurable.
+	//
+	// If CipherSuites is nil, a safe default list is used. The default cipher
+	// suites might change over time.
+	CipherSuites []uint16
+
+	// PreferServerCipherSuites is a legacy field and has no effect.
+	//
+	// It used to control whether the server would follow the client's or the
+	// server's preference. Servers now select the best mutually supported
+	// cipher suite based on logic that takes into account inferred client
+	// hardware, server hardware, and security.
+	//
+	// Deprecated: PreferServerCipherSuites is ignored.
+	PreferServerCipherSuites bool
+
+	// SessionTicketsDisabled may be set to true to disable session ticket and
+	// PSK (resumption) support. Note that on clients, session ticket support is
+	// also disabled if ClientSessionCache is nil.
+	SessionTicketsDisabled bool
+
+	// SessionTicketKey is used by TLS servers to provide session resumption.
+	// See RFC 5077 and the PSK mode of RFC 8446. If zero, it will be filled
+	// with random data before the first server handshake.
+	//
+	// Deprecated: if this field is left at zero, session ticket keys will be
+	// automatically rotated every day and dropped after seven days. For
+	// customizing the rotation schedule or synchronizing servers that are
+	// terminating connections for the same host, use SetSessionTicketKeys.
+	SessionTicketKey [32]byte
+
+	// ClientSessionCache is a cache of ClientSessionState entries for TLS
+	// session resumption. It is only used by clients.
+	ClientSessionCache ClientSessionCache
+
+	// MinVersion contains the minimum TLS version that is acceptable.
+	//
+	// By default, TLS 1.2 is currently used as the minimum when acting as a
+	// client, and TLS 1.0 when acting as a server. TLS 1.0 is the minimum
+	// supported by this package, both as a client and as a server.
+	//
+	// The client-side default can temporarily be reverted to TLS 1.0 by
+	// including the value "x509sha1=1" in the GODEBUG environment variable.
+	// Note that this option will be removed in Go 1.19 (but it will still be
+	// possible to set this field to VersionTLS10 explicitly).
+	MinVersion uint16
+
+	// MaxVersion contains the maximum TLS version that is acceptable.
+	//
+	// By default, the maximum version supported by this package is used,
+	// which is currently TLS 1.3.
+	MaxVersion uint16
+
+	// CurvePreferences contains the elliptic curves that will be used in
+	// an ECDHE handshake, in preference order. If empty, the default will
+	// be used. The client will use the first preference as the type for
+	// its key share in TLS 1.3. This may change in the future.
+	CurvePreferences []CurveID
+
+	// DynamicRecordSizingDisabled disables adaptive sizing of TLS records.
+	// When true, the largest possible TLS record size is always used. When
+	// false, the size of TLS records may be adjusted in an attempt to
+	// improve latency.
+	DynamicRecordSizingDisabled bool
+
+	// Renegotiation controls what types of renegotiation are supported.
+	// The default, none, is correct for the vast majority of applications.
+	Renegotiation RenegotiationSupport
+
+	// KeyLogWriter optionally specifies a destination for TLS master secrets
+	// in NSS key log format that can be used to allow external programs
+	// such as Wireshark to decrypt TLS connections.
+	// See https://developer.mozilla.org/en-US/docs/Mozilla/Projects/NSS/Key_Log_Format.
+	// Use of KeyLogWriter compromises security and should only be
+	// used for debugging.
+	KeyLogWriter io.Writer
+
+	// mutex protects sessionTicketKeys and autoSessionTicketKeys.
+	mutex sync.RWMutex
+	// sessionTicketKeys contains zero or more ticket keys. If set, it means the
+	// the keys were set with SessionTicketKey or SetSessionTicketKeys. The
+	// first key is used for new tickets and any subsequent keys can be used to
+	// decrypt old tickets. The slice contents are not protected by the mutex
+	// and are immutable.
+	sessionTicketKeys []ticketKey
+	// autoSessionTicketKeys is like sessionTicketKeys but is owned by the
+	// auto-rotation logic. See Config.ticketKeys.
+	autoSessionTicketKeys []ticketKey
+}
+
+const (
+	// ticketKeyNameLen is the number of bytes of identifier that is prepended to
+	// an encrypted session ticket in order to identify the key used to encrypt it.
+	ticketKeyNameLen = 16
+
+	// ticketKeyLifetime is how long a ticket key remains valid and can be used to
+	// resume a client connection.
+	ticketKeyLifetime = 7 * 24 * time.Hour // 7 days
+
+	// ticketKeyRotation is how often the server should rotate the session ticket key
+	// that is used for new tickets.
+	ticketKeyRotation = 24 * time.Hour
+)
+
+// ticketKey is the internal representation of a session ticket key.
+type ticketKey struct {
+	// keyName is an opaque byte string that serves to identify the session
+	// ticket key. It's exposed as plaintext in every session ticket.
+	keyName [ticketKeyNameLen]byte
+	aesKey  [16]byte
+	hmacKey [16]byte
+	// created is the time at which this ticket key was created. See Config.ticketKeys.
+	created time.Time
+}
+
+// ticketKeyFromBytes converts from the external representation of a session
+// ticket key to a ticketKey. Externally, session ticket keys are 32 random
+// bytes and this function expands that into sufficient name and key material.
+func (c *Config) ticketKeyFromBytes(b [32]byte) (key ticketKey) {
+	hashed := sha512.Sum512(b[:])
+	copy(key.keyName[:], hashed[:ticketKeyNameLen])
+	copy(key.aesKey[:], hashed[ticketKeyNameLen:ticketKeyNameLen+16])
+	copy(key.hmacKey[:], hashed[ticketKeyNameLen+16:ticketKeyNameLen+32])
+	key.created = c.time()
+	return key
+}
+
+// maxSessionTicketLifetime is the maximum allowed lifetime of a TLS 1.3 session
+// ticket, and the lifetime we set for tickets we send.
+const maxSessionTicketLifetime = 7 * 24 * time.Hour
+
+// Clone returns a shallow clone of c or nil if c is nil. It is safe to clone a Config that is
+// being used concurrently by a TLS client or server.
+func (c *Config) Clone() *Config {
+	if c == nil {
+		return nil
+	}
+	c.mutex.RLock()
+	defer c.mutex.RUnlock()
+	return &Config{
+		Rand:                        c.Rand,
+		Time:                        c.Time,
+		Certificates:                c.Certificates,
+		NameToCertificate:           c.NameToCertificate,
+		GetCertificate:              c.GetCertificate,
+		GetClientCertificate:        c.GetClientCertificate,
+		GetConfigForClient:          c.GetConfigForClient,
+		VerifyPeerCertificate:       c.VerifyPeerCertificate,
+		VerifyConnection:            c.VerifyConnection,
+		RootCAs:                     c.RootCAs,
+		NextProtos:                  c.NextProtos,
+		ServerName:                  c.ServerName,
+		ClientAuth:                  c.ClientAuth,
+		ClientCAs:                   c.ClientCAs,
+		InsecureSkipVerify:          c.InsecureSkipVerify,
+		CipherSuites:                c.CipherSuites,
+		PreferServerCipherSuites:    c.PreferServerCipherSuites,
+		SessionTicketsDisabled:      c.SessionTicketsDisabled,
+		SessionTicketKey:            c.SessionTicketKey,
+		ClientSessionCache:          c.ClientSessionCache,
+		MinVersion:                  c.MinVersion,
+		MaxVersion:                  c.MaxVersion,
+		CurvePreferences:            c.CurvePreferences,
+		DynamicRecordSizingDisabled: c.DynamicRecordSizingDisabled,
+		Renegotiation:               c.Renegotiation,
+		KeyLogWriter:                c.KeyLogWriter,
+		sessionTicketKeys:           c.sessionTicketKeys,
+		autoSessionTicketKeys:       c.autoSessionTicketKeys,
+	}
+}
+
+// deprecatedSessionTicketKey is set as the prefix of SessionTicketKey if it was
+// randomized for backwards compatibility but is not in use.
+var deprecatedSessionTicketKey = []byte("DEPRECATED")
+
+// initLegacySessionTicketKeyRLocked ensures the legacy SessionTicketKey field is
+// randomized if empty, and that sessionTicketKeys is populated from it otherwise.
+func (c *Config) initLegacySessionTicketKeyRLocked() {
+	// Don't write if SessionTicketKey is already defined as our deprecated string,
+	// or if it is defined by the user but sessionTicketKeys is already set.
+	if c.SessionTicketKey != [32]byte{} &&
+		(bytes.HasPrefix(c.SessionTicketKey[:], deprecatedSessionTicketKey) || len(c.sessionTicketKeys) > 0) {
+		return
+	}
+
+	// We need to write some data, so get an exclusive lock and re-check any conditions.
+	c.mutex.RUnlock()
+	defer c.mutex.RLock()
+	c.mutex.Lock()
+	defer c.mutex.Unlock()
+	if c.SessionTicketKey == [32]byte{} {
+		if _, err := io.ReadFull(c.rand(), c.SessionTicketKey[:]); err != nil {
+			panic(fmt.Sprintf("tls: unable to generate random session ticket key: %v", err))
+		}
+		// Write the deprecated prefix at the beginning so we know we created
+		// it. This key with the DEPRECATED prefix isn't used as an actual
+		// session ticket key, and is only randomized in case the application
+		// reuses it for some reason.
+		copy(c.SessionTicketKey[:], deprecatedSessionTicketKey)
+	} else if !bytes.HasPrefix(c.SessionTicketKey[:], deprecatedSessionTicketKey) && len(c.sessionTicketKeys) == 0 {
+		c.sessionTicketKeys = []ticketKey{c.ticketKeyFromBytes(c.SessionTicketKey)}
+	}
+
+}
+
+// ticketKeys returns the ticketKeys for this connection.
+// If configForClient has explicitly set keys, those will
+// be returned. Otherwise, the keys on c will be used and
+// may be rotated if auto-managed.
+// During rotation, any expired session ticket keys are deleted from
+// c.sessionTicketKeys. If the session ticket key that is currently
+// encrypting tickets (ie. the first ticketKey in c.sessionTicketKeys)
+// is not fresh, then a new session ticket key will be
+// created and prepended to c.sessionTicketKeys.
+func (c *Config) ticketKeys(configForClient *Config) []ticketKey {
+	// If the ConfigForClient callback returned a Config with explicitly set
+	// keys, use those, otherwise just use the original Config.
+	if configForClient != nil {
+		configForClient.mutex.RLock()
+		if configForClient.SessionTicketsDisabled {
+			return nil
+		}
+		configForClient.initLegacySessionTicketKeyRLocked()
+		if len(configForClient.sessionTicketKeys) != 0 {
+			ret := configForClient.sessionTicketKeys
+			configForClient.mutex.RUnlock()
+			return ret
+		}
+		configForClient.mutex.RUnlock()
+	}
+
+	c.mutex.RLock()
+	defer c.mutex.RUnlock()
+	if c.SessionTicketsDisabled {
+		return nil
+	}
+	c.initLegacySessionTicketKeyRLocked()
+	if len(c.sessionTicketKeys) != 0 {
+		return c.sessionTicketKeys
+	}
+	// Fast path for the common case where the key is fresh enough.
+	if len(c.autoSessionTicketKeys) > 0 && c.time().Sub(c.autoSessionTicketKeys[0].created) < ticketKeyRotation {
+		return c.autoSessionTicketKeys
+	}
+
+	// autoSessionTicketKeys are managed by auto-rotation.
+	c.mutex.RUnlock()
+	defer c.mutex.RLock()
+	c.mutex.Lock()
+	defer c.mutex.Unlock()
+	// Re-check the condition in case it changed since obtaining the new lock.
+	if len(c.autoSessionTicketKeys) == 0 || c.time().Sub(c.autoSessionTicketKeys[0].created) >= ticketKeyRotation {
+		var newKey [32]byte
+		if _, err := io.ReadFull(c.rand(), newKey[:]); err != nil {
+			panic(fmt.Sprintf("unable to generate random session ticket key: %v", err))
+		}
+		valid := make([]ticketKey, 0, len(c.autoSessionTicketKeys)+1)
+		valid = append(valid, c.ticketKeyFromBytes(newKey))
+		for _, k := range c.autoSessionTicketKeys {
+			// While rotating the current key, also remove any expired ones.
+			if c.time().Sub(k.created) < ticketKeyLifetime {
+				valid = append(valid, k)
+			}
+		}
+		c.autoSessionTicketKeys = valid
+	}
+	return c.autoSessionTicketKeys
+}
+
+// SetSessionTicketKeys updates the session ticket keys for a server.
+//
+// The first key will be used when creating new tickets, while all keys can be
+// used for decrypting tickets. It is safe to call this function while the
+// server is running in order to rotate the session ticket keys. The function
+// will panic if keys is empty.
+//
+// Calling this function will turn off automatic session ticket key rotation.
+//
+// If multiple servers are terminating connections for the same host they should
+// all have the same session ticket keys. If the session ticket keys leaks,
+// previously recorded and future TLS connections using those keys might be
+// compromised.
+func (c *Config) SetSessionTicketKeys(keys [][32]byte) {
+	if len(keys) == 0 {
+		panic("tls: keys must have at least one key")
+	}
+
+	newKeys := make([]ticketKey, len(keys))
+	for i, bytes := range keys {
+		newKeys[i] = c.ticketKeyFromBytes(bytes)
+	}
+
+	c.mutex.Lock()
+	c.sessionTicketKeys = newKeys
+	c.mutex.Unlock()
+}
+
+func (c *Config) rand() io.Reader {
+	r := c.Rand
+	if r == nil {
+		return rand.Reader
+	}
+	return r
+}
+
+func (c *Config) time() time.Time {
+	t := c.Time
+	if t == nil {
+		t = time.Now
+	}
+	return t()
+}
+
+func (c *Config) cipherSuites() []uint16 {
+	if needFIPS() {
+		return fipsCipherSuites(c)
+	}
+	if c.CipherSuites != nil {
+		return c.CipherSuites
+	}
+	return defaultCipherSuites
+}
+
+var supportedVersions = []uint16{
+	VersionTLS13,
+	VersionTLS12,
+	VersionTLS11,
+	VersionTLS10,
+}
+
+// roleClient and roleServer are meant to call supportedVersions and parents
+// with more readability at the callsite.
+const roleClient = true
+const roleServer = false
+
+func (c *Config) supportedVersions(isClient bool) []uint16 {
+	versions := make([]uint16, 0, len(supportedVersions))
+	for _, v := range supportedVersions {
+		if needFIPS() && (v < fipsMinVersion(c) || v > fipsMaxVersion(c)) {
+			continue
+		}
+		if (c == nil || c.MinVersion == 0) &&
+			isClient && v < VersionTLS12 {
+			continue
+		}
+		if c != nil && c.MinVersion != 0 && v < c.MinVersion {
+			continue
+		}
+		if c != nil && c.MaxVersion != 0 && v > c.MaxVersion {
+			continue
+		}
+		versions = append(versions, v)
+	}
+	return versions
+}
+
+func (c *Config) maxSupportedVersion(isClient bool) uint16 {
+	supportedVersions := c.supportedVersions(isClient)
+	if len(supportedVersions) == 0 {
+		return 0
+	}
+	return supportedVersions[0]
+}
+
+// supportedVersionsFromMax returns a list of supported versions derived from a
+// legacy maximum version value. Note that only versions supported by this
+// library are returned. Any newer peer will use supportedVersions anyway.
+func supportedVersionsFromMax(maxVersion uint16) []uint16 {
+	versions := make([]uint16, 0, len(supportedVersions))
+	for _, v := range supportedVersions {
+		if v > maxVersion {
+			continue
+		}
+		versions = append(versions, v)
+	}
+	return versions
+}
+
+var defaultCurvePreferences = []CurveID{X25519, CurveP256, CurveP384, CurveP521}
+
+func (c *Config) curvePreferences() []CurveID {
+	if needFIPS() {
+		return fipsCurvePreferences(c)
+	}
+	if c == nil || len(c.CurvePreferences) == 0 {
+		return defaultCurvePreferences
+	}
+	return c.CurvePreferences
+}
+
+func (c *Config) supportsCurve(curve CurveID) bool {
+	for _, cc := range c.curvePreferences() {
+		if cc == curve {
+			return true
+		}
+	}
+	return false
+}
+
+// mutualVersion returns the protocol version to use given the advertised
+// versions of the peer. Priority is given to the peer preference order.
+func (c *Config) mutualVersion(isClient bool, peerVersions []uint16) (uint16, bool) {
+	supportedVersions := c.supportedVersions(isClient)
+	for _, peerVersion := range peerVersions {
+		for _, v := range supportedVersions {
+			if v == peerVersion {
+				return v, true
+			}
+		}
+	}
+	return 0, false
+}
+
+var errNoCertificates = errors.New("tls: no certificates configured")
+
+// getCertificate returns the best certificate for the given ClientHelloInfo,
+// defaulting to the first element of c.Certificates.
+func (c *Config) getCertificate(clientHello *ClientHelloInfo) (*Certificate, error) {
+	if c.GetCertificate != nil &&
+		(len(c.Certificates) == 0 || len(clientHello.ServerName) > 0) {
+		cert, err := c.GetCertificate(clientHello)
+		if cert != nil || err != nil {
+			return cert, err
+		}
+	}
+
+	if len(c.Certificates) == 0 {
+		return nil, errNoCertificates
+	}
+
+	if len(c.Certificates) == 1 {
+		// There's only one choice, so no point doing any work.
+		return &c.Certificates[0], nil
+	}
+
+	if c.NameToCertificate != nil {
+		name := strings.ToLower(clientHello.ServerName)
+		if cert, ok := c.NameToCertificate[name]; ok {
+			return cert, nil
+		}
+		if len(name) > 0 {
+			labels := strings.Split(name, ".")
+			labels[0] = "*"
+			wildcardName := strings.Join(labels, ".")
+			if cert, ok := c.NameToCertificate[wildcardName]; ok {
+				return cert, nil
+			}
+		}
+	}
+
+	for _, cert := range c.Certificates {
+		if err := clientHello.SupportsCertificate(&cert); err == nil {
+			return &cert, nil
+		}
+	}
+
+	// If nothing matches, return the first certificate.
+	return &c.Certificates[0], nil
+}
+
+// SupportsCertificate returns nil if the provided certificate is supported by
+// the client that sent the ClientHello. Otherwise, it returns an error
+// describing the reason for the incompatibility.
+//
+// If this ClientHelloInfo was passed to a GetConfigForClient or GetCertificate
+// callback, this method will take into account the associated Config. Note that
+// if GetConfigForClient returns a different Config, the change can't be
+// accounted for by this method.
+//
+// This function will call x509.ParseCertificate unless c.Leaf is set, which can
+// incur a significant performance cost.
+func (chi *ClientHelloInfo) SupportsCertificate(c *Certificate) error {
+	// Note we don't currently support certificate_authorities nor
+	// signature_algorithms_cert, and don't check the algorithms of the
+	// signatures on the chain (which anyway are a SHOULD, see RFC 8446,
+	// Section 4.4.2.2).
+
+	config := chi.config
+	if config == nil {
+		config = &Config{}
+	}
+	vers, ok := config.mutualVersion(roleServer, chi.SupportedVersions)
+	if !ok {
+		return errors.New("no mutually supported protocol versions")
+	}
+
+	// If the client specified the name they are trying to connect to, the
+	// certificate needs to be valid for it.
+	if chi.ServerName != "" {
+		x509Cert, err := c.leaf()
+		if err != nil {
+			return fmt.Errorf("failed to parse certificate: %w", err)
+		}
+		if err := x509Cert.VerifyHostname(chi.ServerName); err != nil {
+			return fmt.Errorf("certificate is not valid for requested server name: %w", err)
+		}
+	}
+
+	// supportsRSAFallback returns nil if the certificate and connection support
+	// the static RSA key exchange, and unsupported otherwise. The logic for
+	// supporting static RSA is completely disjoint from the logic for
+	// supporting signed key exchanges, so we just check it as a fallback.
+	supportsRSAFallback := func(unsupported error) error {
+		// TLS 1.3 dropped support for the static RSA key exchange.
+		if vers == VersionTLS13 {
+			return unsupported
+		}
+		// The static RSA key exchange works by decrypting a challenge with the
+		// RSA private key, not by signing, so check the PrivateKey implements
+		// crypto.Decrypter, like *rsa.PrivateKey does.
+		if priv, ok := c.PrivateKey.(crypto.Decrypter); ok {
+			if _, ok := priv.Public().(*rsa.PublicKey); !ok {
+				return unsupported
+			}
+		} else {
+			return unsupported
+		}
+		// Finally, there needs to be a mutual cipher suite that uses the static
+		// RSA key exchange instead of ECDHE.
+		rsaCipherSuite := selectCipherSuite(chi.CipherSuites, config.cipherSuites(), func(c *cipherSuite) bool {
+			if c.flags&suiteECDHE != 0 {
+				return false
+			}
+			if vers < VersionTLS12 && c.flags&suiteTLS12 != 0 {
+				return false
+			}
+			return true
+		})
+		if rsaCipherSuite == nil {
+			return unsupported
+		}
+		return nil
+	}
+
+	// If the client sent the signature_algorithms extension, ensure it supports
+	// schemes we can use with this certificate and TLS version.
+	if len(chi.SignatureSchemes) > 0 {
+		if _, err := selectSignatureScheme(vers, c, chi.SignatureSchemes); err != nil {
+			return supportsRSAFallback(err)
+		}
+	}
+
+	// In TLS 1.3 we are done because supported_groups is only relevant to the
+	// ECDHE computation, point format negotiation is removed, cipher suites are
+	// only relevant to the AEAD choice, and static RSA does not exist.
+	if vers == VersionTLS13 {
+		return nil
+	}
+
+	// The only signed key exchange we support is ECDHE.
+	if !supportsECDHE(config, chi.SupportedCurves, chi.SupportedPoints) {
+		return supportsRSAFallback(errors.New("client doesn't support ECDHE, can only use legacy RSA key exchange"))
+	}
+
+	var ecdsaCipherSuite bool
+	if priv, ok := c.PrivateKey.(crypto.Signer); ok {
+		switch pub := priv.Public().(type) {
+		case *ecdsa.PublicKey:
+			var curve CurveID
+			switch pub.Curve {
+			case elliptic.P256():
+				curve = CurveP256
+			case elliptic.P384():
+				curve = CurveP384
+			case elliptic.P521():
+				curve = CurveP521
+			default:
+				return supportsRSAFallback(unsupportedCertificateError(c))
+			}
+			var curveOk bool
+			for _, c := range chi.SupportedCurves {
+				if c == curve && config.supportsCurve(c) {
+					curveOk = true
+					break
+				}
+			}
+			if !curveOk {
+				return errors.New("client doesn't support certificate curve")
+			}
+			ecdsaCipherSuite = true
+		case ed25519.PublicKey:
+			if vers < VersionTLS12 || len(chi.SignatureSchemes) == 0 {
+				return errors.New("connection doesn't support Ed25519")
+			}
+			ecdsaCipherSuite = true
+		case *rsa.PublicKey:
+		default:
+			return supportsRSAFallback(unsupportedCertificateError(c))
+		}
+	} else {
+		return supportsRSAFallback(unsupportedCertificateError(c))
+	}
+
+	// Make sure that there is a mutually supported cipher suite that works with
+	// this certificate. Cipher suite selection will then apply the logic in
+	// reverse to pick it. See also serverHandshakeState.cipherSuiteOk.
+	cipherSuite := selectCipherSuite(chi.CipherSuites, config.cipherSuites(), func(c *cipherSuite) bool {
+		if c.flags&suiteECDHE == 0 {
+			return false
+		}
+		if c.flags&suiteECSign != 0 {
+			if !ecdsaCipherSuite {
+				return false
+			}
+		} else {
+			if ecdsaCipherSuite {
+				return false
+			}
+		}
+		if vers < VersionTLS12 && c.flags&suiteTLS12 != 0 {
+			return false
+		}
+		return true
+	})
+	if cipherSuite == nil {
+		return supportsRSAFallback(errors.New("client doesn't support any cipher suites compatible with the certificate"))
+	}
+
+	return nil
+}
+
+// SupportsCertificate returns nil if the provided certificate is supported by
+// the server that sent the CertificateRequest. Otherwise, it returns an error
+// describing the reason for the incompatibility.
+func (cri *CertificateRequestInfo) SupportsCertificate(c *Certificate) error {
+	if _, err := selectSignatureScheme(cri.Version, c, cri.SignatureSchemes); err != nil {
+		return err
+	}
+
+	if len(cri.AcceptableCAs) == 0 {
+		return nil
+	}
+
+	for j, cert := range c.Certificate {
+		x509Cert := c.Leaf
+		// Parse the certificate if this isn't the leaf node, or if
+		// chain.Leaf was nil.
+		if j != 0 || x509Cert == nil {
+			var err error
+			if x509Cert, err = x509.ParseCertificate(cert); err != nil {
+				return fmt.Errorf("failed to parse certificate #%d in the chain: %w", j, err)
+			}
+		}
+
+		for _, ca := range cri.AcceptableCAs {
+			if bytes.Equal(x509Cert.RawIssuer, ca) {
+				return nil
+			}
+		}
+	}
+	return errors.New("chain is not signed by an acceptable CA")
+}
+
+// BuildNameToCertificate parses c.Certificates and builds c.NameToCertificate
+// from the CommonName and SubjectAlternateName fields of each of the leaf
+// certificates.
+//
+// Deprecated: NameToCertificate only allows associating a single certificate
+// with a given name. Leave that field nil to let the library select the first
+// compatible chain from Certificates.
+func (c *Config) BuildNameToCertificate() {
+	c.NameToCertificate = make(map[string]*Certificate)
+	for i := range c.Certificates {
+		cert := &c.Certificates[i]
+		x509Cert, err := cert.leaf()
+		if err != nil {
+			continue
+		}
+		// If SANs are *not* present, some clients will consider the certificate
+		// valid for the name in the Common Name.
+		if x509Cert.Subject.CommonName != "" && len(x509Cert.DNSNames) == 0 {
+			c.NameToCertificate[x509Cert.Subject.CommonName] = cert
+		}
+		for _, san := range x509Cert.DNSNames {
+			c.NameToCertificate[san] = cert
+		}
+	}
+}
+
+const (
+	keyLogLabelTLS12           = "CLIENT_RANDOM"
+	keyLogLabelClientHandshake = "CLIENT_HANDSHAKE_TRAFFIC_SECRET"
+	keyLogLabelServerHandshake = "SERVER_HANDSHAKE_TRAFFIC_SECRET"
+	keyLogLabelClientTraffic   = "CLIENT_TRAFFIC_SECRET_0"
+	keyLogLabelServerTraffic   = "SERVER_TRAFFIC_SECRET_0"
+)
+
+func (c *Config) writeKeyLog(label string, clientRandom, secret []byte) error {
+	if c.KeyLogWriter == nil {
+		return nil
+	}
+
+	logLine := []byte(fmt.Sprintf("%s %x %x\n", label, clientRandom, secret))
+
+	writerMutex.Lock()
+	_, err := c.KeyLogWriter.Write(logLine)
+	writerMutex.Unlock()
+
+	return err
+}
+
+// writerMutex protects all KeyLogWriters globally. It is rarely enabled,
+// and is only for debugging, so a global mutex saves space.
+var writerMutex sync.Mutex
+
+// A Certificate is a chain of one or more certificates, leaf first.
+type Certificate struct {
+	Certificate [][]byte
+	// PrivateKey contains the private key corresponding to the public key in
+	// Leaf. This must implement crypto.Signer with an RSA, ECDSA or Ed25519 PublicKey.
+	// For a server up to TLS 1.2, it can also implement crypto.Decrypter with
+	// an RSA PublicKey.
+	PrivateKey crypto.PrivateKey
+	// SupportedSignatureAlgorithms is an optional list restricting what
+	// signature algorithms the PrivateKey can be used for.
+	SupportedSignatureAlgorithms []SignatureScheme
+	// OCSPStaple contains an optional OCSP response which will be served
+	// to clients that request it.
+	OCSPStaple []byte
+	// SignedCertificateTimestamps contains an optional list of Signed
+	// Certificate Timestamps which will be served to clients that request it.
+	SignedCertificateTimestamps [][]byte
+	// Leaf is the parsed form of the leaf certificate, which may be initialized
+	// using x509.ParseCertificate to reduce per-handshake processing. If nil,
+	// the leaf certificate will be parsed as needed.
+	Leaf *x509.Certificate
+}
+
+// leaf returns the parsed leaf certificate, either from c.Leaf or by parsing
+// the corresponding c.Certificate[0].
+func (c *Certificate) leaf() (*x509.Certificate, error) {
+	if c.Leaf != nil {
+		return c.Leaf, nil
+	}
+	return x509.ParseCertificate(c.Certificate[0])
+}
+
+type handshakeMessage interface {
+	marshal() []byte
+	unmarshal([]byte) bool
+}
+
+// lruSessionCache is a ClientSessionCache implementation that uses an LRU
+// caching strategy.
+type lruSessionCache struct {
+	sync.Mutex
+
+	m        map[string]*list.Element
+	q        *list.List
+	capacity int
+}
+
+type lruSessionCacheEntry struct {
+	sessionKey string
+	state      *ClientSessionState
+}
+
+// NewLRUClientSessionCache returns a ClientSessionCache with the given
+// capacity that uses an LRU strategy. If capacity is < 1, a default capacity
+// is used instead.
+func NewLRUClientSessionCache(capacity int) ClientSessionCache {
+	const defaultSessionCacheCapacity = 64
+
+	if capacity < 1 {
+		capacity = defaultSessionCacheCapacity
+	}
+	return &lruSessionCache{
+		m:        make(map[string]*list.Element),
+		q:        list.New(),
+		capacity: capacity,
+	}
+}
+
+// Put adds the provided (sessionKey, cs) pair to the cache. If cs is nil, the entry
+// corresponding to sessionKey is removed from the cache instead.
+func (c *lruSessionCache) Put(sessionKey string, cs *ClientSessionState) {
+	c.Lock()
+	defer c.Unlock()
+
+	if elem, ok := c.m[sessionKey]; ok {
+		if cs == nil {
+			c.q.Remove(elem)
+			delete(c.m, sessionKey)
+		} else {
+			entry := elem.Value.(*lruSessionCacheEntry)
+			entry.state = cs
+			c.q.MoveToFront(elem)
+		}
+		return
+	}
+
+	if c.q.Len() < c.capacity {
+		entry := &lruSessionCacheEntry{sessionKey, cs}
+		c.m[sessionKey] = c.q.PushFront(entry)
+		return
+	}
+
+	elem := c.q.Back()
+	entry := elem.Value.(*lruSessionCacheEntry)
+	delete(c.m, entry.sessionKey)
+	entry.sessionKey = sessionKey
+	entry.state = cs
+	c.q.MoveToFront(elem)
+	c.m[sessionKey] = elem
+}
+
+// Get returns the ClientSessionState value associated with a given key. It
+// returns (nil, false) if no value is found.
+func (c *lruSessionCache) Get(sessionKey string) (*ClientSessionState, bool) {
+	c.Lock()
+	defer c.Unlock()
+
+	if elem, ok := c.m[sessionKey]; ok {
+		c.q.MoveToFront(elem)
+		return elem.Value.(*lruSessionCacheEntry).state, true
+	}
+	return nil, false
+}
+
+var emptyConfig Config
+
+func defaultConfig() *Config {
+	return &emptyConfig
+}
+
+func unexpectedMessageError(wanted, got any) error {
+	return fmt.Errorf("tls: received unexpected handshake message of type %T when waiting for %T", got, wanted)
+}
+
+func isSupportedSignatureAlgorithm(sigAlg SignatureScheme, supportedSignatureAlgorithms []SignatureScheme) bool {
+	for _, s := range supportedSignatureAlgorithms {
+		if s == sigAlg {
+			return true
+		}
+	}
+	return false
+}
diff --git a/contrib/go/_std_1.18/src/crypto/tls/common_string.go b/contrib/go/_std_1.19/src/crypto/tls/common_string.go
index 238108811f..238108811f 100644
--- a/contrib/go/_std_1.18/src/crypto/tls/common_string.go
+++ b/contrib/go/_std_1.19/src/crypto/tls/common_string.go
diff --git a/contrib/go/_std_1.19/src/crypto/tls/conn.go b/contrib/go/_std_1.19/src/crypto/tls/conn.go
new file mode 100644
index 0000000000..1861a312f1
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/tls/conn.go
@@ -0,0 +1,1545 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// TLS low level connection and record layer
+
+package tls
+
+import (
+	"bytes"
+	"context"
+	"crypto/cipher"
+	"crypto/subtle"
+	"crypto/x509"
+	"errors"
+	"fmt"
+	"hash"
+	"io"
+	"net"
+	"sync"
+	"sync/atomic"
+	"time"
+)
+
+// A Conn represents a secured connection.
+// It implements the net.Conn interface.
+type Conn struct {
+	// constant
+	conn        net.Conn
+	isClient    bool
+	handshakeFn func(context.Context) error // (*Conn).clientHandshake or serverHandshake
+
+	// handshakeStatus is 1 if the connection is currently transferring
+	// application data (i.e. is not currently processing a handshake).
+	// handshakeStatus == 1 implies handshakeErr == nil.
+	// This field is only to be accessed with sync/atomic.
+	handshakeStatus uint32
+	// constant after handshake; protected by handshakeMutex
+	handshakeMutex sync.Mutex
+	handshakeErr   error   // error resulting from handshake
+	vers           uint16  // TLS version
+	haveVers       bool    // version has been negotiated
+	config         *Config // configuration passed to constructor
+	// handshakes counts the number of handshakes performed on the
+	// connection so far. If renegotiation is disabled then this is either
+	// zero or one.
+	handshakes       int
+	didResume        bool // whether this connection was a session resumption
+	cipherSuite      uint16
+	ocspResponse     []byte   // stapled OCSP response
+	scts             [][]byte // signed certificate timestamps from server
+	peerCertificates []*x509.Certificate
+	// verifiedChains contains the certificate chains that we built, as
+	// opposed to the ones presented by the server.
+	verifiedChains [][]*x509.Certificate
+	// serverName contains the server name indicated by the client, if any.
+	serverName string
+	// secureRenegotiation is true if the server echoed the secure
+	// renegotiation extension. (This is meaningless as a server because
+	// renegotiation is not supported in that case.)
+	secureRenegotiation bool
+	// ekm is a closure for exporting keying material.
+	ekm func(label string, context []byte, length int) ([]byte, error)
+	// resumptionSecret is the resumption_master_secret for handling
+	// NewSessionTicket messages. nil if config.SessionTicketsDisabled.
+	resumptionSecret []byte
+
+	// ticketKeys is the set of active session ticket keys for this
+	// connection. The first one is used to encrypt new tickets and
+	// all are tried to decrypt tickets.
+	ticketKeys []ticketKey
+
+	// clientFinishedIsFirst is true if the client sent the first Finished
+	// message during the most recent handshake. This is recorded because
+	// the first transmitted Finished message is the tls-unique
+	// channel-binding value.
+	clientFinishedIsFirst bool
+
+	// closeNotifyErr is any error from sending the alertCloseNotify record.
+	closeNotifyErr error
+	// closeNotifySent is true if the Conn attempted to send an
+	// alertCloseNotify record.
+	closeNotifySent bool
+
+	// clientFinished and serverFinished contain the Finished message sent
+	// by the client or server in the most recent handshake. This is
+	// retained to support the renegotiation extension and tls-unique
+	// channel-binding.
+	clientFinished [12]byte
+	serverFinished [12]byte
+
+	// clientProtocol is the negotiated ALPN protocol.
+	clientProtocol string
+
+	// input/output
+	in, out   halfConn
+	rawInput  bytes.Buffer // raw input, starting with a record header
+	input     bytes.Reader // application data waiting to be read, from rawInput.Next
+	hand      bytes.Buffer // handshake data waiting to be read
+	buffering bool         // whether records are buffered in sendBuf
+	sendBuf   []byte       // a buffer of records waiting to be sent
+
+	// bytesSent counts the bytes of application data sent.
+	// packetsSent counts packets.
+	bytesSent   int64
+	packetsSent int64
+
+	// retryCount counts the number of consecutive non-advancing records
+	// received by Conn.readRecord. That is, records that neither advance the
+	// handshake, nor deliver application data. Protected by in.Mutex.
+	retryCount int
+
+	// activeCall is an atomic int32; the low bit is whether Close has
+	// been called. the rest of the bits are the number of goroutines
+	// in Conn.Write.
+	activeCall int32
+
+	tmp [16]byte
+}
+
+// Access to net.Conn methods.
+// Cannot just embed net.Conn because that would
+// export the struct field too.
+
+// LocalAddr returns the local network address.
+func (c *Conn) LocalAddr() net.Addr {
+	return c.conn.LocalAddr()
+}
+
+// RemoteAddr returns the remote network address.
+func (c *Conn) RemoteAddr() net.Addr {
+	return c.conn.RemoteAddr()
+}
+
+// SetDeadline sets the read and write deadlines associated with the connection.
+// A zero value for t means Read and Write will not time out.
+// After a Write has timed out, the TLS state is corrupt and all future writes will return the same error.
+func (c *Conn) SetDeadline(t time.Time) error {
+	return c.conn.SetDeadline(t)
+}
+
+// SetReadDeadline sets the read deadline on the underlying connection.
+// A zero value for t means Read will not time out.
+func (c *Conn) SetReadDeadline(t time.Time) error {
+	return c.conn.SetReadDeadline(t)
+}
+
+// SetWriteDeadline sets the write deadline on the underlying connection.
+// A zero value for t means Write will not time out.
+// After a Write has timed out, the TLS state is corrupt and all future writes will return the same error.
+func (c *Conn) SetWriteDeadline(t time.Time) error {
+	return c.conn.SetWriteDeadline(t)
+}
+
+// NetConn returns the underlying connection that is wrapped by c.
+// Note that writing to or reading from this connection directly will corrupt the
+// TLS session.
+func (c *Conn) NetConn() net.Conn {
+	return c.conn
+}
+
+// A halfConn represents one direction of the record layer
+// connection, either sending or receiving.
+type halfConn struct {
+	sync.Mutex
+
+	err     error  // first permanent error
+	version uint16 // protocol version
+	cipher  any    // cipher algorithm
+	mac     hash.Hash
+	seq     [8]byte // 64-bit sequence number
+
+	scratchBuf [13]byte // to avoid allocs; interface method args escape
+
+	nextCipher any       // next encryption state
+	nextMac    hash.Hash // next MAC algorithm
+
+	trafficSecret []byte // current TLS 1.3 traffic secret
+}
+
+type permanentError struct {
+	err net.Error
+}
+
+func (e *permanentError) Error() string   { return e.err.Error() }
+func (e *permanentError) Unwrap() error   { return e.err }
+func (e *permanentError) Timeout() bool   { return e.err.Timeout() }
+func (e *permanentError) Temporary() bool { return false }
+
+func (hc *halfConn) setErrorLocked(err error) error {
+	if e, ok := err.(net.Error); ok {
+		hc.err = &permanentError{err: e}
+	} else {
+		hc.err = err
+	}
+	return hc.err
+}
+
+// prepareCipherSpec sets the encryption and MAC states
+// that a subsequent changeCipherSpec will use.
+func (hc *halfConn) prepareCipherSpec(version uint16, cipher any, mac hash.Hash) {
+	hc.version = version
+	hc.nextCipher = cipher
+	hc.nextMac = mac
+}
+
+// changeCipherSpec changes the encryption and MAC states
+// to the ones previously passed to prepareCipherSpec.
+func (hc *halfConn) changeCipherSpec() error {
+	if hc.nextCipher == nil || hc.version == VersionTLS13 {
+		return alertInternalError
+	}
+	hc.cipher = hc.nextCipher
+	hc.mac = hc.nextMac
+	hc.nextCipher = nil
+	hc.nextMac = nil
+	for i := range hc.seq {
+		hc.seq[i] = 0
+	}
+	return nil
+}
+
+func (hc *halfConn) setTrafficSecret(suite *cipherSuiteTLS13, secret []byte) {
+	hc.trafficSecret = secret
+	key, iv := suite.trafficKey(secret)
+	hc.cipher = suite.aead(key, iv)
+	for i := range hc.seq {
+		hc.seq[i] = 0
+	}
+}
+
+// incSeq increments the sequence number.
+func (hc *halfConn) incSeq() {
+	for i := 7; i >= 0; i-- {
+		hc.seq[i]++
+		if hc.seq[i] != 0 {
+			return
+		}
+	}
+
+	// Not allowed to let sequence number wrap.
+	// Instead, must renegotiate before it does.
+	// Not likely enough to bother.
+	panic("TLS: sequence number wraparound")
+}
+
+// explicitNonceLen returns the number of bytes of explicit nonce or IV included
+// in each record. Explicit nonces are present only in CBC modes after TLS 1.0
+// and in certain AEAD modes in TLS 1.2.
+func (hc *halfConn) explicitNonceLen() int {
+	if hc.cipher == nil {
+		return 0
+	}
+
+	switch c := hc.cipher.(type) {
+	case cipher.Stream:
+		return 0
+	case aead:
+		return c.explicitNonceLen()
+	case cbcMode:
+		// TLS 1.1 introduced a per-record explicit IV to fix the BEAST attack.
+		if hc.version >= VersionTLS11 {
+			return c.BlockSize()
+		}
+		return 0
+	default:
+		panic("unknown cipher type")
+	}
+}
+
+// extractPadding returns, in constant time, the length of the padding to remove
+// from the end of payload. It also returns a byte which is equal to 255 if the
+// padding was valid and 0 otherwise. See RFC 2246, Section 6.2.3.2.
+func extractPadding(payload []byte) (toRemove int, good byte) {
+	if len(payload) < 1 {
+		return 0, 0
+	}
+
+	paddingLen := payload[len(payload)-1]
+	t := uint(len(payload)-1) - uint(paddingLen)
+	// if len(payload) >= (paddingLen - 1) then the MSB of t is zero
+	good = byte(int32(^t) >> 31)
+
+	// The maximum possible padding length plus the actual length field
+	toCheck := 256
+	// The length of the padded data is public, so we can use an if here
+	if toCheck > len(payload) {
+		toCheck = len(payload)
+	}
+
+	for i := 0; i < toCheck; i++ {
+		t := uint(paddingLen) - uint(i)
+		// if i <= paddingLen then the MSB of t is zero
+		mask := byte(int32(^t) >> 31)
+		b := payload[len(payload)-1-i]
+		good &^= mask&paddingLen ^ mask&b
+	}
+
+	// We AND together the bits of good and replicate the result across
+	// all the bits.
+	good &= good << 4
+	good &= good << 2
+	good &= good << 1
+	good = uint8(int8(good) >> 7)
+
+	// Zero the padding length on error. This ensures any unchecked bytes
+	// are included in the MAC. Otherwise, an attacker that could
+	// distinguish MAC failures from padding failures could mount an attack
+	// similar to POODLE in SSL 3.0: given a good ciphertext that uses a
+	// full block's worth of padding, replace the final block with another
+	// block. If the MAC check passed but the padding check failed, the
+	// last byte of that block decrypted to the block size.
+	//
+	// See also macAndPaddingGood logic below.
+	paddingLen &= good
+
+	toRemove = int(paddingLen) + 1
+	return
+}
+
+func roundUp(a, b int) int {
+	return a + (b-a%b)%b
+}
+
+// cbcMode is an interface for block ciphers using cipher block chaining.
+type cbcMode interface {
+	cipher.BlockMode
+	SetIV([]byte)
+}
+
+// decrypt authenticates and decrypts the record if protection is active at
+// this stage. The returned plaintext might overlap with the input.
+func (hc *halfConn) decrypt(record []byte) ([]byte, recordType, error) {
+	var plaintext []byte
+	typ := recordType(record[0])
+	payload := record[recordHeaderLen:]
+
+	// In TLS 1.3, change_cipher_spec messages are to be ignored without being
+	// decrypted. See RFC 8446, Appendix D.4.
+	if hc.version == VersionTLS13 && typ == recordTypeChangeCipherSpec {
+		return payload, typ, nil
+	}
+
+	paddingGood := byte(255)
+	paddingLen := 0
+
+	explicitNonceLen := hc.explicitNonceLen()
+
+	if hc.cipher != nil {
+		switch c := hc.cipher.(type) {
+		case cipher.Stream:
+			c.XORKeyStream(payload, payload)
+		case aead:
+			if len(payload) < explicitNonceLen {
+				return nil, 0, alertBadRecordMAC
+			}
+			nonce := payload[:explicitNonceLen]
+			if len(nonce) == 0 {
+				nonce = hc.seq[:]
+			}
+			payload = payload[explicitNonceLen:]
+
+			var additionalData []byte
+			if hc.version == VersionTLS13 {
+				additionalData = record[:recordHeaderLen]
+			} else {
+				additionalData = append(hc.scratchBuf[:0], hc.seq[:]...)
+				additionalData = append(additionalData, record[:3]...)
+				n := len(payload) - c.Overhead()
+				additionalData = append(additionalData, byte(n>>8), byte(n))
+			}
+
+			var err error
+			plaintext, err = c.Open(payload[:0], nonce, payload, additionalData)
+			if err != nil {
+				return nil, 0, alertBadRecordMAC
+			}
+		case cbcMode:
+			blockSize := c.BlockSize()
+			minPayload := explicitNonceLen + roundUp(hc.mac.Size()+1, blockSize)
+			if len(payload)%blockSize != 0 || len(payload) < minPayload {
+				return nil, 0, alertBadRecordMAC
+			}
+
+			if explicitNonceLen > 0 {
+				c.SetIV(payload[:explicitNonceLen])
+				payload = payload[explicitNonceLen:]
+			}
+			c.CryptBlocks(payload, payload)
+
+			// In a limited attempt to protect against CBC padding oracles like
+			// Lucky13, the data past paddingLen (which is secret) is passed to
+			// the MAC function as extra data, to be fed into the HMAC after
+			// computing the digest. This makes the MAC roughly constant time as
+			// long as the digest computation is constant time and does not
+			// affect the subsequent write, modulo cache effects.
+			paddingLen, paddingGood = extractPadding(payload)
+		default:
+			panic("unknown cipher type")
+		}
+
+		if hc.version == VersionTLS13 {
+			if typ != recordTypeApplicationData {
+				return nil, 0, alertUnexpectedMessage
+			}
+			if len(plaintext) > maxPlaintext+1 {
+				return nil, 0, alertRecordOverflow
+			}
+			// Remove padding and find the ContentType scanning from the end.
+			for i := len(plaintext) - 1; i >= 0; i-- {
+				if plaintext[i] != 0 {
+					typ = recordType(plaintext[i])
+					plaintext = plaintext[:i]
+					break
+				}
+				if i == 0 {
+					return nil, 0, alertUnexpectedMessage
+				}
+			}
+		}
+	} else {
+		plaintext = payload
+	}
+
+	if hc.mac != nil {
+		macSize := hc.mac.Size()
+		if len(payload) < macSize {
+			return nil, 0, alertBadRecordMAC
+		}
+
+		n := len(payload) - macSize - paddingLen
+		n = subtle.ConstantTimeSelect(int(uint32(n)>>31), 0, n) // if n < 0 { n = 0 }
+		record[3] = byte(n >> 8)
+		record[4] = byte(n)
+		remoteMAC := payload[n : n+macSize]
+		localMAC := tls10MAC(hc.mac, hc.scratchBuf[:0], hc.seq[:], record[:recordHeaderLen], payload[:n], payload[n+macSize:])
+
+		// This is equivalent to checking the MACs and paddingGood
+		// separately, but in constant-time to prevent distinguishing
+		// padding failures from MAC failures. Depending on what value
+		// of paddingLen was returned on bad padding, distinguishing
+		// bad MAC from bad padding can lead to an attack.
+		//
+		// See also the logic at the end of extractPadding.
+		macAndPaddingGood := subtle.ConstantTimeCompare(localMAC, remoteMAC) & int(paddingGood)
+		if macAndPaddingGood != 1 {
+			return nil, 0, alertBadRecordMAC
+		}
+
+		plaintext = payload[:n]
+	}
+
+	hc.incSeq()
+	return plaintext, typ, nil
+}
+
+// sliceForAppend extends the input slice by n bytes. head is the full extended
+// slice, while tail is the appended part. If the original slice has sufficient
+// capacity no allocation is performed.
+func sliceForAppend(in []byte, n int) (head, tail []byte) {
+	if total := len(in) + n; cap(in) >= total {
+		head = in[:total]
+	} else {
+		head = make([]byte, total)
+		copy(head, in)
+	}
+	tail = head[len(in):]
+	return
+}
+
+// encrypt encrypts payload, adding the appropriate nonce and/or MAC, and
+// appends it to record, which must already contain the record header.
+func (hc *halfConn) encrypt(record, payload []byte, rand io.Reader) ([]byte, error) {
+	if hc.cipher == nil {
+		return append(record, payload...), nil
+	}
+
+	var explicitNonce []byte
+	if explicitNonceLen := hc.explicitNonceLen(); explicitNonceLen > 0 {
+		record, explicitNonce = sliceForAppend(record, explicitNonceLen)
+		if _, isCBC := hc.cipher.(cbcMode); !isCBC && explicitNonceLen < 16 {
+			// The AES-GCM construction in TLS has an explicit nonce so that the
+			// nonce can be random. However, the nonce is only 8 bytes which is
+			// too small for a secure, random nonce. Therefore we use the
+			// sequence number as the nonce. The 3DES-CBC construction also has
+			// an 8 bytes nonce but its nonces must be unpredictable (see RFC
+			// 5246, Appendix F.3), forcing us to use randomness. That's not
+			// 3DES' biggest problem anyway because the birthday bound on block
+			// collision is reached first due to its similarly small block size
+			// (see the Sweet32 attack).
+			copy(explicitNonce, hc.seq[:])
+		} else {
+			if _, err := io.ReadFull(rand, explicitNonce); err != nil {
+				return nil, err
+			}
+		}
+	}
+
+	var dst []byte
+	switch c := hc.cipher.(type) {
+	case cipher.Stream:
+		mac := tls10MAC(hc.mac, hc.scratchBuf[:0], hc.seq[:], record[:recordHeaderLen], payload, nil)
+		record, dst = sliceForAppend(record, len(payload)+len(mac))
+		c.XORKeyStream(dst[:len(payload)], payload)
+		c.XORKeyStream(dst[len(payload):], mac)
+	case aead:
+		nonce := explicitNonce
+		if len(nonce) == 0 {
+			nonce = hc.seq[:]
+		}
+
+		if hc.version == VersionTLS13 {
+			record = append(record, payload...)
+
+			// Encrypt the actual ContentType and replace the plaintext one.
+			record = append(record, record[0])
+			record[0] = byte(recordTypeApplicationData)
+
+			n := len(payload) + 1 + c.Overhead()
+			record[3] = byte(n >> 8)
+			record[4] = byte(n)
+
+			record = c.Seal(record[:recordHeaderLen],
+				nonce, record[recordHeaderLen:], record[:recordHeaderLen])
+		} else {
+			additionalData := append(hc.scratchBuf[:0], hc.seq[:]...)
+			additionalData = append(additionalData, record[:recordHeaderLen]...)
+			record = c.Seal(record, nonce, payload, additionalData)
+		}
+	case cbcMode:
+		mac := tls10MAC(hc.mac, hc.scratchBuf[:0], hc.seq[:], record[:recordHeaderLen], payload, nil)
+		blockSize := c.BlockSize()
+		plaintextLen := len(payload) + len(mac)
+		paddingLen := blockSize - plaintextLen%blockSize
+		record, dst = sliceForAppend(record, plaintextLen+paddingLen)
+		copy(dst, payload)
+		copy(dst[len(payload):], mac)
+		for i := plaintextLen; i < len(dst); i++ {
+			dst[i] = byte(paddingLen - 1)
+		}
+		if len(explicitNonce) > 0 {
+			c.SetIV(explicitNonce)
+		}
+		c.CryptBlocks(dst, dst)
+	default:
+		panic("unknown cipher type")
+	}
+
+	// Update length to include nonce, MAC and any block padding needed.
+	n := len(record) - recordHeaderLen
+	record[3] = byte(n >> 8)
+	record[4] = byte(n)
+	hc.incSeq()
+
+	return record, nil
+}
+
+// RecordHeaderError is returned when a TLS record header is invalid.
+type RecordHeaderError struct {
+	// Msg contains a human readable string that describes the error.
+	Msg string
+	// RecordHeader contains the five bytes of TLS record header that
+	// triggered the error.
+	RecordHeader [5]byte
+	// Conn provides the underlying net.Conn in the case that a client
+	// sent an initial handshake that didn't look like TLS.
+	// It is nil if there's already been a handshake or a TLS alert has
+	// been written to the connection.
+	Conn net.Conn
+}
+
+func (e RecordHeaderError) Error() string { return "tls: " + e.Msg }
+
+func (c *Conn) newRecordHeaderError(conn net.Conn, msg string) (err RecordHeaderError) {
+	err.Msg = msg
+	err.Conn = conn
+	copy(err.RecordHeader[:], c.rawInput.Bytes())
+	return err
+}
+
+func (c *Conn) readRecord() error {
+	return c.readRecordOrCCS(false)
+}
+
+func (c *Conn) readChangeCipherSpec() error {
+	return c.readRecordOrCCS(true)
+}
+
+// readRecordOrCCS reads one or more TLS records from the connection and
+// updates the record layer state. Some invariants:
+//   - c.in must be locked
+//   - c.input must be empty
+//
+// During the handshake one and only one of the following will happen:
+//   - c.hand grows
+//   - c.in.changeCipherSpec is called
+//   - an error is returned
+//
+// After the handshake one and only one of the following will happen:
+//   - c.hand grows
+//   - c.input is set
+//   - an error is returned
+func (c *Conn) readRecordOrCCS(expectChangeCipherSpec bool) error {
+	if c.in.err != nil {
+		return c.in.err
+	}
+	handshakeComplete := c.handshakeComplete()
+
+	// This function modifies c.rawInput, which owns the c.input memory.
+	if c.input.Len() != 0 {
+		return c.in.setErrorLocked(errors.New("tls: internal error: attempted to read record with pending application data"))
+	}
+	c.input.Reset(nil)
+
+	// Read header, payload.
+	if err := c.readFromUntil(c.conn, recordHeaderLen); err != nil {
+		// RFC 8446, Section 6.1 suggests that EOF without an alertCloseNotify
+		// is an error, but popular web sites seem to do this, so we accept it
+		// if and only if at the record boundary.
+		if err == io.ErrUnexpectedEOF && c.rawInput.Len() == 0 {
+			err = io.EOF
+		}
+		if e, ok := err.(net.Error); !ok || !e.Temporary() {
+			c.in.setErrorLocked(err)
+		}
+		return err
+	}
+	hdr := c.rawInput.Bytes()[:recordHeaderLen]
+	typ := recordType(hdr[0])
+
+	// No valid TLS record has a type of 0x80, however SSLv2 handshakes
+	// start with a uint16 length where the MSB is set and the first record
+	// is always < 256 bytes long. Therefore typ == 0x80 strongly suggests
+	// an SSLv2 client.
+	if !handshakeComplete && typ == 0x80 {
+		c.sendAlert(alertProtocolVersion)
+		return c.in.setErrorLocked(c.newRecordHeaderError(nil, "unsupported SSLv2 handshake received"))
+	}
+
+	vers := uint16(hdr[1])<<8 | uint16(hdr[2])
+	n := int(hdr[3])<<8 | int(hdr[4])
+	if c.haveVers && c.vers != VersionTLS13 && vers != c.vers {
+		c.sendAlert(alertProtocolVersion)
+		msg := fmt.Sprintf("received record with version %x when expecting version %x", vers, c.vers)
+		return c.in.setErrorLocked(c.newRecordHeaderError(nil, msg))
+	}
+	if !c.haveVers {
+		// First message, be extra suspicious: this might not be a TLS
+		// client. Bail out before reading a full 'body', if possible.
+		// The current max version is 3.3 so if the version is >= 16.0,
+		// it's probably not real.
+		if (typ != recordTypeAlert && typ != recordTypeHandshake) || vers >= 0x1000 {
+			return c.in.setErrorLocked(c.newRecordHeaderError(c.conn, "first record does not look like a TLS handshake"))
+		}
+	}
+	if c.vers == VersionTLS13 && n > maxCiphertextTLS13 || n > maxCiphertext {
+		c.sendAlert(alertRecordOverflow)
+		msg := fmt.Sprintf("oversized record received with length %d", n)
+		return c.in.setErrorLocked(c.newRecordHeaderError(nil, msg))
+	}
+	if err := c.readFromUntil(c.conn, recordHeaderLen+n); err != nil {
+		if e, ok := err.(net.Error); !ok || !e.Temporary() {
+			c.in.setErrorLocked(err)
+		}
+		return err
+	}
+
+	// Process message.
+	record := c.rawInput.Next(recordHeaderLen + n)
+	data, typ, err := c.in.decrypt(record)
+	if err != nil {
+		return c.in.setErrorLocked(c.sendAlert(err.(alert)))
+	}
+	if len(data) > maxPlaintext {
+		return c.in.setErrorLocked(c.sendAlert(alertRecordOverflow))
+	}
+
+	// Application Data messages are always protected.
+	if c.in.cipher == nil && typ == recordTypeApplicationData {
+		return c.in.setErrorLocked(c.sendAlert(alertUnexpectedMessage))
+	}
+
+	if typ != recordTypeAlert && typ != recordTypeChangeCipherSpec && len(data) > 0 {
+		// This is a state-advancing message: reset the retry count.
+		c.retryCount = 0
+	}
+
+	// Handshake messages MUST NOT be interleaved with other record types in TLS 1.3.
+	if c.vers == VersionTLS13 && typ != recordTypeHandshake && c.hand.Len() > 0 {
+		return c.in.setErrorLocked(c.sendAlert(alertUnexpectedMessage))
+	}
+
+	switch typ {
+	default:
+		return c.in.setErrorLocked(c.sendAlert(alertUnexpectedMessage))
+
+	case recordTypeAlert:
+		if len(data) != 2 {
+			return c.in.setErrorLocked(c.sendAlert(alertUnexpectedMessage))
+		}
+		if alert(data[1]) == alertCloseNotify {
+			return c.in.setErrorLocked(io.EOF)
+		}
+		if c.vers == VersionTLS13 {
+			return c.in.setErrorLocked(&net.OpError{Op: "remote error", Err: alert(data[1])})
+		}
+		switch data[0] {
+		case alertLevelWarning:
+			// Drop the record on the floor and retry.
+			return c.retryReadRecord(expectChangeCipherSpec)
+		case alertLevelError:
+			return c.in.setErrorLocked(&net.OpError{Op: "remote error", Err: alert(data[1])})
+		default:
+			return c.in.setErrorLocked(c.sendAlert(alertUnexpectedMessage))
+		}
+
+	case recordTypeChangeCipherSpec:
+		if len(data) != 1 || data[0] != 1 {
+			return c.in.setErrorLocked(c.sendAlert(alertDecodeError))
+		}
+		// Handshake messages are not allowed to fragment across the CCS.
+		if c.hand.Len() > 0 {
+			return c.in.setErrorLocked(c.sendAlert(alertUnexpectedMessage))
+		}
+		// In TLS 1.3, change_cipher_spec records are ignored until the
+		// Finished. See RFC 8446, Appendix D.4. Note that according to Section
+		// 5, a server can send a ChangeCipherSpec before its ServerHello, when
+		// c.vers is still unset. That's not useful though and suspicious if the
+		// server then selects a lower protocol version, so don't allow that.
+		if c.vers == VersionTLS13 {
+			return c.retryReadRecord(expectChangeCipherSpec)
+		}
+		if !expectChangeCipherSpec {
+			return c.in.setErrorLocked(c.sendAlert(alertUnexpectedMessage))
+		}
+		if err := c.in.changeCipherSpec(); err != nil {
+			return c.in.setErrorLocked(c.sendAlert(err.(alert)))
+		}
+
+	case recordTypeApplicationData:
+		if !handshakeComplete || expectChangeCipherSpec {
+			return c.in.setErrorLocked(c.sendAlert(alertUnexpectedMessage))
+		}
+		// Some OpenSSL servers send empty records in order to randomize the
+		// CBC IV. Ignore a limited number of empty records.
+		if len(data) == 0 {
+			return c.retryReadRecord(expectChangeCipherSpec)
+		}
+		// Note that data is owned by c.rawInput, following the Next call above,
+		// to avoid copying the plaintext. This is safe because c.rawInput is
+		// not read from or written to until c.input is drained.
+		c.input.Reset(data)
+
+	case recordTypeHandshake:
+		if len(data) == 0 || expectChangeCipherSpec {
+			return c.in.setErrorLocked(c.sendAlert(alertUnexpectedMessage))
+		}
+		c.hand.Write(data)
+	}
+
+	return nil
+}
+
+// retryReadRecord recurs into readRecordOrCCS to drop a non-advancing record, like
+// a warning alert, empty application_data, or a change_cipher_spec in TLS 1.3.
+func (c *Conn) retryReadRecord(expectChangeCipherSpec bool) error {
+	c.retryCount++
+	if c.retryCount > maxUselessRecords {
+		c.sendAlert(alertUnexpectedMessage)
+		return c.in.setErrorLocked(errors.New("tls: too many ignored records"))
+	}
+	return c.readRecordOrCCS(expectChangeCipherSpec)
+}
+
+// atLeastReader reads from R, stopping with EOF once at least N bytes have been
+// read. It is different from an io.LimitedReader in that it doesn't cut short
+// the last Read call, and in that it considers an early EOF an error.
+type atLeastReader struct {
+	R io.Reader
+	N int64
+}
+
+func (r *atLeastReader) Read(p []byte) (int, error) {
+	if r.N <= 0 {
+		return 0, io.EOF
+	}
+	n, err := r.R.Read(p)
+	r.N -= int64(n) // won't underflow unless len(p) >= n > 9223372036854775809
+	if r.N > 0 && err == io.EOF {
+		return n, io.ErrUnexpectedEOF
+	}
+	if r.N <= 0 && err == nil {
+		return n, io.EOF
+	}
+	return n, err
+}
+
+// readFromUntil reads from r into c.rawInput until c.rawInput contains
+// at least n bytes or else returns an error.
+func (c *Conn) readFromUntil(r io.Reader, n int) error {
+	if c.rawInput.Len() >= n {
+		return nil
+	}
+	needs := n - c.rawInput.Len()
+	// There might be extra input waiting on the wire. Make a best effort
+	// attempt to fetch it so that it can be used in (*Conn).Read to
+	// "predict" closeNotify alerts.
+	c.rawInput.Grow(needs + bytes.MinRead)
+	_, err := c.rawInput.ReadFrom(&atLeastReader{r, int64(needs)})
+	return err
+}
+
+// sendAlert sends a TLS alert message.
+func (c *Conn) sendAlertLocked(err alert) error {
+	switch err {
+	case alertNoRenegotiation, alertCloseNotify:
+		c.tmp[0] = alertLevelWarning
+	default:
+		c.tmp[0] = alertLevelError
+	}
+	c.tmp[1] = byte(err)
+
+	_, writeErr := c.writeRecordLocked(recordTypeAlert, c.tmp[0:2])
+	if err == alertCloseNotify {
+		// closeNotify is a special case in that it isn't an error.
+		return writeErr
+	}
+
+	return c.out.setErrorLocked(&net.OpError{Op: "local error", Err: err})
+}
+
+// sendAlert sends a TLS alert message.
+func (c *Conn) sendAlert(err alert) error {
+	c.out.Lock()
+	defer c.out.Unlock()
+	return c.sendAlertLocked(err)
+}
+
+const (
+	// tcpMSSEstimate is a conservative estimate of the TCP maximum segment
+	// size (MSS). A constant is used, rather than querying the kernel for
+	// the actual MSS, to avoid complexity. The value here is the IPv6
+	// minimum MTU (1280 bytes) minus the overhead of an IPv6 header (40
+	// bytes) and a TCP header with timestamps (32 bytes).
+	tcpMSSEstimate = 1208
+
+	// recordSizeBoostThreshold is the number of bytes of application data
+	// sent after which the TLS record size will be increased to the
+	// maximum.
+	recordSizeBoostThreshold = 128 * 1024
+)
+
+// maxPayloadSizeForWrite returns the maximum TLS payload size to use for the
+// next application data record. There is the following trade-off:
+//
+//   - For latency-sensitive applications, such as web browsing, each TLS
+//     record should fit in one TCP segment.
+//   - For throughput-sensitive applications, such as large file transfers,
+//     larger TLS records better amortize framing and encryption overheads.
+//
+// A simple heuristic that works well in practice is to use small records for
+// the first 1MB of data, then use larger records for subsequent data, and
+// reset back to smaller records after the connection becomes idle. See "High
+// Performance Web Networking", Chapter 4, or:
+// https://www.igvita.com/2013/10/24/optimizing-tls-record-size-and-buffering-latency/
+//
+// In the interests of simplicity and determinism, this code does not attempt
+// to reset the record size once the connection is idle, however.
+func (c *Conn) maxPayloadSizeForWrite(typ recordType) int {
+	if c.config.DynamicRecordSizingDisabled || typ != recordTypeApplicationData {
+		return maxPlaintext
+	}
+
+	if c.bytesSent >= recordSizeBoostThreshold {
+		return maxPlaintext
+	}
+
+	// Subtract TLS overheads to get the maximum payload size.
+	payloadBytes := tcpMSSEstimate - recordHeaderLen - c.out.explicitNonceLen()
+	if c.out.cipher != nil {
+		switch ciph := c.out.cipher.(type) {
+		case cipher.Stream:
+			payloadBytes -= c.out.mac.Size()
+		case cipher.AEAD:
+			payloadBytes -= ciph.Overhead()
+		case cbcMode:
+			blockSize := ciph.BlockSize()
+			// The payload must fit in a multiple of blockSize, with
+			// room for at least one padding byte.
+			payloadBytes = (payloadBytes & ^(blockSize - 1)) - 1
+			// The MAC is appended before padding so affects the
+			// payload size directly.
+			payloadBytes -= c.out.mac.Size()
+		default:
+			panic("unknown cipher type")
+		}
+	}
+	if c.vers == VersionTLS13 {
+		payloadBytes-- // encrypted ContentType
+	}
+
+	// Allow packet growth in arithmetic progression up to max.
+	pkt := c.packetsSent
+	c.packetsSent++
+	if pkt > 1000 {
+		return maxPlaintext // avoid overflow in multiply below
+	}
+
+	n := payloadBytes * int(pkt+1)
+	if n > maxPlaintext {
+		n = maxPlaintext
+	}
+	return n
+}
+
+func (c *Conn) write(data []byte) (int, error) {
+	if c.buffering {
+		c.sendBuf = append(c.sendBuf, data...)
+		return len(data), nil
+	}
+
+	n, err := c.conn.Write(data)
+	c.bytesSent += int64(n)
+	return n, err
+}
+
+func (c *Conn) flush() (int, error) {
+	if len(c.sendBuf) == 0 {
+		return 0, nil
+	}
+
+	n, err := c.conn.Write(c.sendBuf)
+	c.bytesSent += int64(n)
+	c.sendBuf = nil
+	c.buffering = false
+	return n, err
+}
+
+// outBufPool pools the record-sized scratch buffers used by writeRecordLocked.
+var outBufPool = sync.Pool{
+	New: func() any {
+		return new([]byte)
+	},
+}
+
+// writeRecordLocked writes a TLS record with the given type and payload to the
+// connection and updates the record layer state.
+func (c *Conn) writeRecordLocked(typ recordType, data []byte) (int, error) {
+	outBufPtr := outBufPool.Get().(*[]byte)
+	outBuf := *outBufPtr
+	defer func() {
+		// You might be tempted to simplify this by just passing &outBuf to Put,
+		// but that would make the local copy of the outBuf slice header escape
+		// to the heap, causing an allocation. Instead, we keep around the
+		// pointer to the slice header returned by Get, which is already on the
+		// heap, and overwrite and return that.
+		*outBufPtr = outBuf
+		outBufPool.Put(outBufPtr)
+	}()
+
+	var n int
+	for len(data) > 0 {
+		m := len(data)
+		if maxPayload := c.maxPayloadSizeForWrite(typ); m > maxPayload {
+			m = maxPayload
+		}
+
+		_, outBuf = sliceForAppend(outBuf[:0], recordHeaderLen)
+		outBuf[0] = byte(typ)
+		vers := c.vers
+		if vers == 0 {
+			// Some TLS servers fail if the record version is
+			// greater than TLS 1.0 for the initial ClientHello.
+			vers = VersionTLS10
+		} else if vers == VersionTLS13 {
+			// TLS 1.3 froze the record layer version to 1.2.
+			// See RFC 8446, Section 5.1.
+			vers = VersionTLS12
+		}
+		outBuf[1] = byte(vers >> 8)
+		outBuf[2] = byte(vers)
+		outBuf[3] = byte(m >> 8)
+		outBuf[4] = byte(m)
+
+		var err error
+		outBuf, err = c.out.encrypt(outBuf, data[:m], c.config.rand())
+		if err != nil {
+			return n, err
+		}
+		if _, err := c.write(outBuf); err != nil {
+			return n, err
+		}
+		n += m
+		data = data[m:]
+	}
+
+	if typ == recordTypeChangeCipherSpec && c.vers != VersionTLS13 {
+		if err := c.out.changeCipherSpec(); err != nil {
+			return n, c.sendAlertLocked(err.(alert))
+		}
+	}
+
+	return n, nil
+}
+
+// writeRecord writes a TLS record with the given type and payload to the
+// connection and updates the record layer state.
+func (c *Conn) writeRecord(typ recordType, data []byte) (int, error) {
+	c.out.Lock()
+	defer c.out.Unlock()
+
+	return c.writeRecordLocked(typ, data)
+}
+
+// readHandshake reads the next handshake message from
+// the record layer.
+func (c *Conn) readHandshake() (any, error) {
+	for c.hand.Len() < 4 {
+		if err := c.readRecord(); err != nil {
+			return nil, err
+		}
+	}
+
+	data := c.hand.Bytes()
+	n := int(data[1])<<16 | int(data[2])<<8 | int(data[3])
+	if n > maxHandshake {
+		c.sendAlertLocked(alertInternalError)
+		return nil, c.in.setErrorLocked(fmt.Errorf("tls: handshake message of length %d bytes exceeds maximum of %d bytes", n, maxHandshake))
+	}
+	for c.hand.Len() < 4+n {
+		if err := c.readRecord(); err != nil {
+			return nil, err
+		}
+	}
+	data = c.hand.Next(4 + n)
+	var m handshakeMessage
+	switch data[0] {
+	case typeHelloRequest:
+		m = new(helloRequestMsg)
+	case typeClientHello:
+		m = new(clientHelloMsg)
+	case typeServerHello:
+		m = new(serverHelloMsg)
+	case typeNewSessionTicket:
+		if c.vers == VersionTLS13 {
+			m = new(newSessionTicketMsgTLS13)
+		} else {
+			m = new(newSessionTicketMsg)
+		}
+	case typeCertificate:
+		if c.vers == VersionTLS13 {
+			m = new(certificateMsgTLS13)
+		} else {
+			m = new(certificateMsg)
+		}
+	case typeCertificateRequest:
+		if c.vers == VersionTLS13 {
+			m = new(certificateRequestMsgTLS13)
+		} else {
+			m = &certificateRequestMsg{
+				hasSignatureAlgorithm: c.vers >= VersionTLS12,
+			}
+		}
+	case typeCertificateStatus:
+		m = new(certificateStatusMsg)
+	case typeServerKeyExchange:
+		m = new(serverKeyExchangeMsg)
+	case typeServerHelloDone:
+		m = new(serverHelloDoneMsg)
+	case typeClientKeyExchange:
+		m = new(clientKeyExchangeMsg)
+	case typeCertificateVerify:
+		m = &certificateVerifyMsg{
+			hasSignatureAlgorithm: c.vers >= VersionTLS12,
+		}
+	case typeFinished:
+		m = new(finishedMsg)
+	case typeEncryptedExtensions:
+		m = new(encryptedExtensionsMsg)
+	case typeEndOfEarlyData:
+		m = new(endOfEarlyDataMsg)
+	case typeKeyUpdate:
+		m = new(keyUpdateMsg)
+	default:
+		return nil, c.in.setErrorLocked(c.sendAlert(alertUnexpectedMessage))
+	}
+
+	// The handshake message unmarshalers
+	// expect to be able to keep references to data,
+	// so pass in a fresh copy that won't be overwritten.
+	data = append([]byte(nil), data...)
+
+	if !m.unmarshal(data) {
+		return nil, c.in.setErrorLocked(c.sendAlert(alertUnexpectedMessage))
+	}
+	return m, nil
+}
+
+var (
+	errShutdown = errors.New("tls: protocol is shutdown")
+)
+
+// Write writes data to the connection.
+//
+// As Write calls Handshake, in order to prevent indefinite blocking a deadline
+// must be set for both Read and Write before Write is called when the handshake
+// has not yet completed. See SetDeadline, SetReadDeadline, and
+// SetWriteDeadline.
+func (c *Conn) Write(b []byte) (int, error) {
+	// interlock with Close below
+	for {
+		x := atomic.LoadInt32(&c.activeCall)
+		if x&1 != 0 {
+			return 0, net.ErrClosed
+		}
+		if atomic.CompareAndSwapInt32(&c.activeCall, x, x+2) {
+			break
+		}
+	}
+	defer atomic.AddInt32(&c.activeCall, -2)
+
+	if err := c.Handshake(); err != nil {
+		return 0, err
+	}
+
+	c.out.Lock()
+	defer c.out.Unlock()
+
+	if err := c.out.err; err != nil {
+		return 0, err
+	}
+
+	if !c.handshakeComplete() {
+		return 0, alertInternalError
+	}
+
+	if c.closeNotifySent {
+		return 0, errShutdown
+	}
+
+	// TLS 1.0 is susceptible to a chosen-plaintext
+	// attack when using block mode ciphers due to predictable IVs.
+	// This can be prevented by splitting each Application Data
+	// record into two records, effectively randomizing the IV.
+	//
+	// https://www.openssl.org/~bodo/tls-cbc.txt
+	// https://bugzilla.mozilla.org/show_bug.cgi?id=665814
+	// https://www.imperialviolet.org/2012/01/15/beastfollowup.html
+
+	var m int
+	if len(b) > 1 && c.vers == VersionTLS10 {
+		if _, ok := c.out.cipher.(cipher.BlockMode); ok {
+			n, err := c.writeRecordLocked(recordTypeApplicationData, b[:1])
+			if err != nil {
+				return n, c.out.setErrorLocked(err)
+			}
+			m, b = 1, b[1:]
+		}
+	}
+
+	n, err := c.writeRecordLocked(recordTypeApplicationData, b)
+	return n + m, c.out.setErrorLocked(err)
+}
+
+// handleRenegotiation processes a HelloRequest handshake message.
+func (c *Conn) handleRenegotiation() error {
+	if c.vers == VersionTLS13 {
+		return errors.New("tls: internal error: unexpected renegotiation")
+	}
+
+	msg, err := c.readHandshake()
+	if err != nil {
+		return err
+	}
+
+	helloReq, ok := msg.(*helloRequestMsg)
+	if !ok {
+		c.sendAlert(alertUnexpectedMessage)
+		return unexpectedMessageError(helloReq, msg)
+	}
+
+	if !c.isClient {
+		return c.sendAlert(alertNoRenegotiation)
+	}
+
+	switch c.config.Renegotiation {
+	case RenegotiateNever:
+		return c.sendAlert(alertNoRenegotiation)
+	case RenegotiateOnceAsClient:
+		if c.handshakes > 1 {
+			return c.sendAlert(alertNoRenegotiation)
+		}
+	case RenegotiateFreelyAsClient:
+		// Ok.
+	default:
+		c.sendAlert(alertInternalError)
+		return errors.New("tls: unknown Renegotiation value")
+	}
+
+	c.handshakeMutex.Lock()
+	defer c.handshakeMutex.Unlock()
+
+	atomic.StoreUint32(&c.handshakeStatus, 0)
+	if c.handshakeErr = c.clientHandshake(context.Background()); c.handshakeErr == nil {
+		c.handshakes++
+	}
+	return c.handshakeErr
+}
+
+// handlePostHandshakeMessage processes a handshake message arrived after the
+// handshake is complete. Up to TLS 1.2, it indicates the start of a renegotiation.
+func (c *Conn) handlePostHandshakeMessage() error {
+	if c.vers != VersionTLS13 {
+		return c.handleRenegotiation()
+	}
+
+	msg, err := c.readHandshake()
+	if err != nil {
+		return err
+	}
+
+	c.retryCount++
+	if c.retryCount > maxUselessRecords {
+		c.sendAlert(alertUnexpectedMessage)
+		return c.in.setErrorLocked(errors.New("tls: too many non-advancing records"))
+	}
+
+	switch msg := msg.(type) {
+	case *newSessionTicketMsgTLS13:
+		return c.handleNewSessionTicket(msg)
+	case *keyUpdateMsg:
+		return c.handleKeyUpdate(msg)
+	default:
+		c.sendAlert(alertUnexpectedMessage)
+		return fmt.Errorf("tls: received unexpected handshake message of type %T", msg)
+	}
+}
+
+func (c *Conn) handleKeyUpdate(keyUpdate *keyUpdateMsg) error {
+	cipherSuite := cipherSuiteTLS13ByID(c.cipherSuite)
+	if cipherSuite == nil {
+		return c.in.setErrorLocked(c.sendAlert(alertInternalError))
+	}
+
+	newSecret := cipherSuite.nextTrafficSecret(c.in.trafficSecret)
+	c.in.setTrafficSecret(cipherSuite, newSecret)
+
+	if keyUpdate.updateRequested {
+		c.out.Lock()
+		defer c.out.Unlock()
+
+		msg := &keyUpdateMsg{}
+		_, err := c.writeRecordLocked(recordTypeHandshake, msg.marshal())
+		if err != nil {
+			// Surface the error at the next write.
+			c.out.setErrorLocked(err)
+			return nil
+		}
+
+		newSecret := cipherSuite.nextTrafficSecret(c.out.trafficSecret)
+		c.out.setTrafficSecret(cipherSuite, newSecret)
+	}
+
+	return nil
+}
+
+// Read reads data from the connection.
+//
+// As Read calls Handshake, in order to prevent indefinite blocking a deadline
+// must be set for both Read and Write before Read is called when the handshake
+// has not yet completed. See SetDeadline, SetReadDeadline, and
+// SetWriteDeadline.
+func (c *Conn) Read(b []byte) (int, error) {
+	if err := c.Handshake(); err != nil {
+		return 0, err
+	}
+	if len(b) == 0 {
+		// Put this after Handshake, in case people were calling
+		// Read(nil) for the side effect of the Handshake.
+		return 0, nil
+	}
+
+	c.in.Lock()
+	defer c.in.Unlock()
+
+	for c.input.Len() == 0 {
+		if err := c.readRecord(); err != nil {
+			return 0, err
+		}
+		for c.hand.Len() > 0 {
+			if err := c.handlePostHandshakeMessage(); err != nil {
+				return 0, err
+			}
+		}
+	}
+
+	n, _ := c.input.Read(b)
+
+	// If a close-notify alert is waiting, read it so that we can return (n,
+	// EOF) instead of (n, nil), to signal to the HTTP response reading
+	// goroutine that the connection is now closed. This eliminates a race
+	// where the HTTP response reading goroutine would otherwise not observe
+	// the EOF until its next read, by which time a client goroutine might
+	// have already tried to reuse the HTTP connection for a new request.
+	// See https://golang.org/cl/76400046 and https://golang.org/issue/3514
+	if n != 0 && c.input.Len() == 0 && c.rawInput.Len() > 0 &&
+		recordType(c.rawInput.Bytes()[0]) == recordTypeAlert {
+		if err := c.readRecord(); err != nil {
+			return n, err // will be io.EOF on closeNotify
+		}
+	}
+
+	return n, nil
+}
+
+// Close closes the connection.
+func (c *Conn) Close() error {
+	// Interlock with Conn.Write above.
+	var x int32
+	for {
+		x = atomic.LoadInt32(&c.activeCall)
+		if x&1 != 0 {
+			return net.ErrClosed
+		}
+		if atomic.CompareAndSwapInt32(&c.activeCall, x, x|1) {
+			break
+		}
+	}
+	if x != 0 {
+		// io.Writer and io.Closer should not be used concurrently.
+		// If Close is called while a Write is currently in-flight,
+		// interpret that as a sign that this Close is really just
+		// being used to break the Write and/or clean up resources and
+		// avoid sending the alertCloseNotify, which may block
+		// waiting on handshakeMutex or the c.out mutex.
+		return c.conn.Close()
+	}
+
+	var alertErr error
+	if c.handshakeComplete() {
+		if err := c.closeNotify(); err != nil {
+			alertErr = fmt.Errorf("tls: failed to send closeNotify alert (but connection was closed anyway): %w", err)
+		}
+	}
+
+	if err := c.conn.Close(); err != nil {
+		return err
+	}
+	return alertErr
+}
+
+var errEarlyCloseWrite = errors.New("tls: CloseWrite called before handshake complete")
+
+// CloseWrite shuts down the writing side of the connection. It should only be
+// called once the handshake has completed and does not call CloseWrite on the
+// underlying connection. Most callers should just use Close.
+func (c *Conn) CloseWrite() error {
+	if !c.handshakeComplete() {
+		return errEarlyCloseWrite
+	}
+
+	return c.closeNotify()
+}
+
+func (c *Conn) closeNotify() error {
+	c.out.Lock()
+	defer c.out.Unlock()
+
+	if !c.closeNotifySent {
+		// Set a Write Deadline to prevent possibly blocking forever.
+		c.SetWriteDeadline(time.Now().Add(time.Second * 5))
+		c.closeNotifyErr = c.sendAlertLocked(alertCloseNotify)
+		c.closeNotifySent = true
+		// Any subsequent writes will fail.
+		c.SetWriteDeadline(time.Now())
+	}
+	return c.closeNotifyErr
+}
+
+// Handshake runs the client or server handshake
+// protocol if it has not yet been run.
+//
+// Most uses of this package need not call Handshake explicitly: the
+// first Read or Write will call it automatically.
+//
+// For control over canceling or setting a timeout on a handshake, use
+// HandshakeContext or the Dialer's DialContext method instead.
+func (c *Conn) Handshake() error {
+	return c.HandshakeContext(context.Background())
+}
+
+// HandshakeContext runs the client or server handshake
+// protocol if it has not yet been run.
+//
+// The provided Context must be non-nil. If the context is canceled before
+// the handshake is complete, the handshake is interrupted and an error is returned.
+// Once the handshake has completed, cancellation of the context will not affect the
+// connection.
+//
+// Most uses of this package need not call HandshakeContext explicitly: the
+// first Read or Write will call it automatically.
+func (c *Conn) HandshakeContext(ctx context.Context) error {
+	// Delegate to unexported method for named return
+	// without confusing documented signature.
+	return c.handshakeContext(ctx)
+}
+
+func (c *Conn) handshakeContext(ctx context.Context) (ret error) {
+	// Fast sync/atomic-based exit if there is no handshake in flight and the
+	// last one succeeded without an error. Avoids the expensive context setup
+	// and mutex for most Read and Write calls.
+	if c.handshakeComplete() {
+		return nil
+	}
+
+	handshakeCtx, cancel := context.WithCancel(ctx)
+	// Note: defer this before starting the "interrupter" goroutine
+	// so that we can tell the difference between the input being canceled and
+	// this cancellation. In the former case, we need to close the connection.
+	defer cancel()
+
+	// Start the "interrupter" goroutine, if this context might be canceled.
+	// (The background context cannot).
+	//
+	// The interrupter goroutine waits for the input context to be done and
+	// closes the connection if this happens before the function returns.
+	if ctx.Done() != nil {
+		done := make(chan struct{})
+		interruptRes := make(chan error, 1)
+		defer func() {
+			close(done)
+			if ctxErr := <-interruptRes; ctxErr != nil {
+				// Return context error to user.
+				ret = ctxErr
+			}
+		}()
+		go func() {
+			select {
+			case <-handshakeCtx.Done():
+				// Close the connection, discarding the error
+				_ = c.conn.Close()
+				interruptRes <- handshakeCtx.Err()
+			case <-done:
+				interruptRes <- nil
+			}
+		}()
+	}
+
+	c.handshakeMutex.Lock()
+	defer c.handshakeMutex.Unlock()
+
+	if err := c.handshakeErr; err != nil {
+		return err
+	}
+	if c.handshakeComplete() {
+		return nil
+	}
+
+	c.in.Lock()
+	defer c.in.Unlock()
+
+	c.handshakeErr = c.handshakeFn(handshakeCtx)
+	if c.handshakeErr == nil {
+		c.handshakes++
+	} else {
+		// If an error occurred during the handshake try to flush the
+		// alert that might be left in the buffer.
+		c.flush()
+	}
+
+	if c.handshakeErr == nil && !c.handshakeComplete() {
+		c.handshakeErr = errors.New("tls: internal error: handshake should have had a result")
+	}
+	if c.handshakeErr != nil && c.handshakeComplete() {
+		panic("tls: internal error: handshake returned an error but is marked successful")
+	}
+
+	return c.handshakeErr
+}
+
+// ConnectionState returns basic TLS details about the connection.
+func (c *Conn) ConnectionState() ConnectionState {
+	c.handshakeMutex.Lock()
+	defer c.handshakeMutex.Unlock()
+	return c.connectionStateLocked()
+}
+
+func (c *Conn) connectionStateLocked() ConnectionState {
+	var state ConnectionState
+	state.HandshakeComplete = c.handshakeComplete()
+	state.Version = c.vers
+	state.NegotiatedProtocol = c.clientProtocol
+	state.DidResume = c.didResume
+	state.NegotiatedProtocolIsMutual = true
+	state.ServerName = c.serverName
+	state.CipherSuite = c.cipherSuite
+	state.PeerCertificates = c.peerCertificates
+	state.VerifiedChains = c.verifiedChains
+	state.SignedCertificateTimestamps = c.scts
+	state.OCSPResponse = c.ocspResponse
+	if !c.didResume && c.vers != VersionTLS13 {
+		if c.clientFinishedIsFirst {
+			state.TLSUnique = c.clientFinished[:]
+		} else {
+			state.TLSUnique = c.serverFinished[:]
+		}
+	}
+	if c.config.Renegotiation != RenegotiateNever {
+		state.ekm = noExportedKeyingMaterial
+	} else {
+		state.ekm = c.ekm
+	}
+	return state
+}
+
+// OCSPResponse returns the stapled OCSP response from the TLS server, if
+// any. (Only valid for client connections.)
+func (c *Conn) OCSPResponse() []byte {
+	c.handshakeMutex.Lock()
+	defer c.handshakeMutex.Unlock()
+
+	return c.ocspResponse
+}
+
+// VerifyHostname checks that the peer certificate chain is valid for
+// connecting to host. If so, it returns nil; if not, it returns an error
+// describing the problem.
+func (c *Conn) VerifyHostname(host string) error {
+	c.handshakeMutex.Lock()
+	defer c.handshakeMutex.Unlock()
+	if !c.isClient {
+		return errors.New("tls: VerifyHostname called on TLS server connection")
+	}
+	if !c.handshakeComplete() {
+		return errors.New("tls: handshake has not yet been performed")
+	}
+	if len(c.verifiedChains) == 0 {
+		return errors.New("tls: handshake did not verify certificate chain")
+	}
+	return c.peerCertificates[0].VerifyHostname(host)
+}
+
+func (c *Conn) handshakeComplete() bool {
+	return atomic.LoadUint32(&c.handshakeStatus) == 1
+}
diff --git a/contrib/go/_std_1.19/src/crypto/tls/handshake_client.go b/contrib/go/_std_1.19/src/crypto/tls/handshake_client.go
new file mode 100644
index 0000000000..e61e3eb540
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/tls/handshake_client.go
@@ -0,0 +1,1017 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package tls
+
+import (
+	"bytes"
+	"context"
+	"crypto"
+	"crypto/ecdsa"
+	"crypto/ed25519"
+	"crypto/rsa"
+	"crypto/subtle"
+	"crypto/x509"
+	"errors"
+	"fmt"
+	"hash"
+	"io"
+	"net"
+	"strings"
+	"sync/atomic"
+	"time"
+)
+
+type clientHandshakeState struct {
+	c            *Conn
+	ctx          context.Context
+	serverHello  *serverHelloMsg
+	hello        *clientHelloMsg
+	suite        *cipherSuite
+	finishedHash finishedHash
+	masterSecret []byte
+	session      *ClientSessionState
+}
+
+var testingOnlyForceClientHelloSignatureAlgorithms []SignatureScheme
+
+func (c *Conn) makeClientHello() (*clientHelloMsg, ecdheParameters, error) {
+	config := c.config
+	if len(config.ServerName) == 0 && !config.InsecureSkipVerify {
+		return nil, nil, errors.New("tls: either ServerName or InsecureSkipVerify must be specified in the tls.Config")
+	}
+
+	nextProtosLength := 0
+	for _, proto := range config.NextProtos {
+		if l := len(proto); l == 0 || l > 255 {
+			return nil, nil, errors.New("tls: invalid NextProtos value")
+		} else {
+			nextProtosLength += 1 + l
+		}
+	}
+	if nextProtosLength > 0xffff {
+		return nil, nil, errors.New("tls: NextProtos values too large")
+	}
+
+	supportedVersions := config.supportedVersions(roleClient)
+	if len(supportedVersions) == 0 {
+		return nil, nil, errors.New("tls: no supported versions satisfy MinVersion and MaxVersion")
+	}
+
+	clientHelloVersion := config.maxSupportedVersion(roleClient)
+	// The version at the beginning of the ClientHello was capped at TLS 1.2
+	// for compatibility reasons. The supported_versions extension is used
+	// to negotiate versions now. See RFC 8446, Section 4.2.1.
+	if clientHelloVersion > VersionTLS12 {
+		clientHelloVersion = VersionTLS12
+	}
+
+	hello := &clientHelloMsg{
+		vers:                         clientHelloVersion,
+		compressionMethods:           []uint8{compressionNone},
+		random:                       make([]byte, 32),
+		sessionId:                    make([]byte, 32),
+		ocspStapling:                 true,
+		scts:                         true,
+		serverName:                   hostnameInSNI(config.ServerName),
+		supportedCurves:              config.curvePreferences(),
+		supportedPoints:              []uint8{pointFormatUncompressed},
+		secureRenegotiationSupported: true,
+		alpnProtocols:                config.NextProtos,
+		supportedVersions:            supportedVersions,
+	}
+
+	if c.handshakes > 0 {
+		hello.secureRenegotiation = c.clientFinished[:]
+	}
+
+	preferenceOrder := cipherSuitesPreferenceOrder
+	if !hasAESGCMHardwareSupport {
+		preferenceOrder = cipherSuitesPreferenceOrderNoAES
+	}
+	configCipherSuites := config.cipherSuites()
+	hello.cipherSuites = make([]uint16, 0, len(configCipherSuites))
+
+	for _, suiteId := range preferenceOrder {
+		suite := mutualCipherSuite(configCipherSuites, suiteId)
+		if suite == nil {
+			continue
+		}
+		// Don't advertise TLS 1.2-only cipher suites unless
+		// we're attempting TLS 1.2.
+		if hello.vers < VersionTLS12 && suite.flags&suiteTLS12 != 0 {
+			continue
+		}
+		hello.cipherSuites = append(hello.cipherSuites, suiteId)
+	}
+
+	_, err := io.ReadFull(config.rand(), hello.random)
+	if err != nil {
+		return nil, nil, errors.New("tls: short read from Rand: " + err.Error())
+	}
+
+	// A random session ID is used to detect when the server accepted a ticket
+	// and is resuming a session (see RFC 5077). In TLS 1.3, it's always set as
+	// a compatibility measure (see RFC 8446, Section 4.1.2).
+	if _, err := io.ReadFull(config.rand(), hello.sessionId); err != nil {
+		return nil, nil, errors.New("tls: short read from Rand: " + err.Error())
+	}
+
+	if hello.vers >= VersionTLS12 {
+		hello.supportedSignatureAlgorithms = supportedSignatureAlgorithms()
+	}
+	if testingOnlyForceClientHelloSignatureAlgorithms != nil {
+		hello.supportedSignatureAlgorithms = testingOnlyForceClientHelloSignatureAlgorithms
+	}
+
+	var params ecdheParameters
+	if hello.supportedVersions[0] == VersionTLS13 {
+		if hasAESGCMHardwareSupport {
+			hello.cipherSuites = append(hello.cipherSuites, defaultCipherSuitesTLS13...)
+		} else {
+			hello.cipherSuites = append(hello.cipherSuites, defaultCipherSuitesTLS13NoAES...)
+		}
+
+		curveID := config.curvePreferences()[0]
+		if _, ok := curveForCurveID(curveID); curveID != X25519 && !ok {
+			return nil, nil, errors.New("tls: CurvePreferences includes unsupported curve")
+		}
+		params, err = generateECDHEParameters(config.rand(), curveID)
+		if err != nil {
+			return nil, nil, err
+		}
+		hello.keyShares = []keyShare{{group: curveID, data: params.PublicKey()}}
+	}
+
+	return hello, params, nil
+}
+
+func (c *Conn) clientHandshake(ctx context.Context) (err error) {
+	if c.config == nil {
+		c.config = defaultConfig()
+	}
+
+	// This may be a renegotiation handshake, in which case some fields
+	// need to be reset.
+	c.didResume = false
+
+	hello, ecdheParams, err := c.makeClientHello()
+	if err != nil {
+		return err
+	}
+	c.serverName = hello.serverName
+
+	cacheKey, session, earlySecret, binderKey := c.loadSession(hello)
+	if cacheKey != "" && session != nil {
+		defer func() {
+			// If we got a handshake failure when resuming a session, throw away
+			// the session ticket. See RFC 5077, Section 3.2.
+			//
+			// RFC 8446 makes no mention of dropping tickets on failure, but it
+			// does require servers to abort on invalid binders, so we need to
+			// delete tickets to recover from a corrupted PSK.
+			if err != nil {
+				c.config.ClientSessionCache.Put(cacheKey, nil)
+			}
+		}()
+	}
+
+	if _, err := c.writeRecord(recordTypeHandshake, hello.marshal()); err != nil {
+		return err
+	}
+
+	msg, err := c.readHandshake()
+	if err != nil {
+		return err
+	}
+
+	serverHello, ok := msg.(*serverHelloMsg)
+	if !ok {
+		c.sendAlert(alertUnexpectedMessage)
+		return unexpectedMessageError(serverHello, msg)
+	}
+
+	if err := c.pickTLSVersion(serverHello); err != nil {
+		return err
+	}
+
+	// If we are negotiating a protocol version that's lower than what we
+	// support, check for the server downgrade canaries.
+	// See RFC 8446, Section 4.1.3.
+	maxVers := c.config.maxSupportedVersion(roleClient)
+	tls12Downgrade := string(serverHello.random[24:]) == downgradeCanaryTLS12
+	tls11Downgrade := string(serverHello.random[24:]) == downgradeCanaryTLS11
+	if maxVers == VersionTLS13 && c.vers <= VersionTLS12 && (tls12Downgrade || tls11Downgrade) ||
+		maxVers == VersionTLS12 && c.vers <= VersionTLS11 && tls11Downgrade {
+		c.sendAlert(alertIllegalParameter)
+		return errors.New("tls: downgrade attempt detected, possibly due to a MitM attack or a broken middlebox")
+	}
+
+	if c.vers == VersionTLS13 {
+		hs := &clientHandshakeStateTLS13{
+			c:           c,
+			ctx:         ctx,
+			serverHello: serverHello,
+			hello:       hello,
+			ecdheParams: ecdheParams,
+			session:     session,
+			earlySecret: earlySecret,
+			binderKey:   binderKey,
+		}
+
+		// In TLS 1.3, session tickets are delivered after the handshake.
+		return hs.handshake()
+	}
+
+	hs := &clientHandshakeState{
+		c:           c,
+		ctx:         ctx,
+		serverHello: serverHello,
+		hello:       hello,
+		session:     session,
+	}
+
+	if err := hs.handshake(); err != nil {
+		return err
+	}
+
+	// If we had a successful handshake and hs.session is different from
+	// the one already cached - cache a new one.
+	if cacheKey != "" && hs.session != nil && session != hs.session {
+		c.config.ClientSessionCache.Put(cacheKey, hs.session)
+	}
+
+	return nil
+}
+
+func (c *Conn) loadSession(hello *clientHelloMsg) (cacheKey string,
+	session *ClientSessionState, earlySecret, binderKey []byte) {
+	if c.config.SessionTicketsDisabled || c.config.ClientSessionCache == nil {
+		return "", nil, nil, nil
+	}
+
+	hello.ticketSupported = true
+
+	if hello.supportedVersions[0] == VersionTLS13 {
+		// Require DHE on resumption as it guarantees forward secrecy against
+		// compromise of the session ticket key. See RFC 8446, Section 4.2.9.
+		hello.pskModes = []uint8{pskModeDHE}
+	}
+
+	// Session resumption is not allowed if renegotiating because
+	// renegotiation is primarily used to allow a client to send a client
+	// certificate, which would be skipped if session resumption occurred.
+	if c.handshakes != 0 {
+		return "", nil, nil, nil
+	}
+
+	// Try to resume a previously negotiated TLS session, if available.
+	cacheKey = clientSessionCacheKey(c.conn.RemoteAddr(), c.config)
+	session, ok := c.config.ClientSessionCache.Get(cacheKey)
+	if !ok || session == nil {
+		return cacheKey, nil, nil, nil
+	}
+
+	// Check that version used for the previous session is still valid.
+	versOk := false
+	for _, v := range hello.supportedVersions {
+		if v == session.vers {
+			versOk = true
+			break
+		}
+	}
+	if !versOk {
+		return cacheKey, nil, nil, nil
+	}
+
+	// Check that the cached server certificate is not expired, and that it's
+	// valid for the ServerName. This should be ensured by the cache key, but
+	// protect the application from a faulty ClientSessionCache implementation.
+	if !c.config.InsecureSkipVerify {
+		if len(session.verifiedChains) == 0 {
+			// The original connection had InsecureSkipVerify, while this doesn't.
+			return cacheKey, nil, nil, nil
+		}
+		serverCert := session.serverCertificates[0]
+		if c.config.time().After(serverCert.NotAfter) {
+			// Expired certificate, delete the entry.
+			c.config.ClientSessionCache.Put(cacheKey, nil)
+			return cacheKey, nil, nil, nil
+		}
+		if err := serverCert.VerifyHostname(c.config.ServerName); err != nil {
+			return cacheKey, nil, nil, nil
+		}
+	}
+
+	if session.vers != VersionTLS13 {
+		// In TLS 1.2 the cipher suite must match the resumed session. Ensure we
+		// are still offering it.
+		if mutualCipherSuite(hello.cipherSuites, session.cipherSuite) == nil {
+			return cacheKey, nil, nil, nil
+		}
+
+		hello.sessionTicket = session.sessionTicket
+		return
+	}
+
+	// Check that the session ticket is not expired.
+	if c.config.time().After(session.useBy) {
+		c.config.ClientSessionCache.Put(cacheKey, nil)
+		return cacheKey, nil, nil, nil
+	}
+
+	// In TLS 1.3 the KDF hash must match the resumed session. Ensure we
+	// offer at least one cipher suite with that hash.
+	cipherSuite := cipherSuiteTLS13ByID(session.cipherSuite)
+	if cipherSuite == nil {
+		return cacheKey, nil, nil, nil
+	}
+	cipherSuiteOk := false
+	for _, offeredID := range hello.cipherSuites {
+		offeredSuite := cipherSuiteTLS13ByID(offeredID)
+		if offeredSuite != nil && offeredSuite.hash == cipherSuite.hash {
+			cipherSuiteOk = true
+			break
+		}
+	}
+	if !cipherSuiteOk {
+		return cacheKey, nil, nil, nil
+	}
+
+	// Set the pre_shared_key extension. See RFC 8446, Section 4.2.11.1.
+	ticketAge := uint32(c.config.time().Sub(session.receivedAt) / time.Millisecond)
+	identity := pskIdentity{
+		label:               session.sessionTicket,
+		obfuscatedTicketAge: ticketAge + session.ageAdd,
+	}
+	hello.pskIdentities = []pskIdentity{identity}
+	hello.pskBinders = [][]byte{make([]byte, cipherSuite.hash.Size())}
+
+	// Compute the PSK binders. See RFC 8446, Section 4.2.11.2.
+	psk := cipherSuite.expandLabel(session.masterSecret, "resumption",
+		session.nonce, cipherSuite.hash.Size())
+	earlySecret = cipherSuite.extract(psk, nil)
+	binderKey = cipherSuite.deriveSecret(earlySecret, resumptionBinderLabel, nil)
+	transcript := cipherSuite.hash.New()
+	transcript.Write(hello.marshalWithoutBinders())
+	pskBinders := [][]byte{cipherSuite.finishedHash(binderKey, transcript)}
+	hello.updateBinders(pskBinders)
+
+	return
+}
+
+func (c *Conn) pickTLSVersion(serverHello *serverHelloMsg) error {
+	peerVersion := serverHello.vers
+	if serverHello.supportedVersion != 0 {
+		peerVersion = serverHello.supportedVersion
+	}
+
+	vers, ok := c.config.mutualVersion(roleClient, []uint16{peerVersion})
+	if !ok {
+		c.sendAlert(alertProtocolVersion)
+		return fmt.Errorf("tls: server selected unsupported protocol version %x", peerVersion)
+	}
+
+	c.vers = vers
+	c.haveVers = true
+	c.in.version = vers
+	c.out.version = vers
+
+	return nil
+}
+
+// Does the handshake, either a full one or resumes old session. Requires hs.c,
+// hs.hello, hs.serverHello, and, optionally, hs.session to be set.
+func (hs *clientHandshakeState) handshake() error {
+	c := hs.c
+
+	isResume, err := hs.processServerHello()
+	if err != nil {
+		return err
+	}
+
+	hs.finishedHash = newFinishedHash(c.vers, hs.suite)
+
+	// No signatures of the handshake are needed in a resumption.
+	// Otherwise, in a full handshake, if we don't have any certificates
+	// configured then we will never send a CertificateVerify message and
+	// thus no signatures are needed in that case either.
+	if isResume || (len(c.config.Certificates) == 0 && c.config.GetClientCertificate == nil) {
+		hs.finishedHash.discardHandshakeBuffer()
+	}
+
+	hs.finishedHash.Write(hs.hello.marshal())
+	hs.finishedHash.Write(hs.serverHello.marshal())
+
+	c.buffering = true
+	c.didResume = isResume
+	if isResume {
+		if err := hs.establishKeys(); err != nil {
+			return err
+		}
+		if err := hs.readSessionTicket(); err != nil {
+			return err
+		}
+		if err := hs.readFinished(c.serverFinished[:]); err != nil {
+			return err
+		}
+		c.clientFinishedIsFirst = false
+		// Make sure the connection is still being verified whether or not this
+		// is a resumption. Resumptions currently don't reverify certificates so
+		// they don't call verifyServerCertificate. See Issue 31641.
+		if c.config.VerifyConnection != nil {
+			if err := c.config.VerifyConnection(c.connectionStateLocked()); err != nil {
+				c.sendAlert(alertBadCertificate)
+				return err
+			}
+		}
+		if err := hs.sendFinished(c.clientFinished[:]); err != nil {
+			return err
+		}
+		if _, err := c.flush(); err != nil {
+			return err
+		}
+	} else {
+		if err := hs.doFullHandshake(); err != nil {
+			return err
+		}
+		if err := hs.establishKeys(); err != nil {
+			return err
+		}
+		if err := hs.sendFinished(c.clientFinished[:]); err != nil {
+			return err
+		}
+		if _, err := c.flush(); err != nil {
+			return err
+		}
+		c.clientFinishedIsFirst = true
+		if err := hs.readSessionTicket(); err != nil {
+			return err
+		}
+		if err := hs.readFinished(c.serverFinished[:]); err != nil {
+			return err
+		}
+	}
+
+	c.ekm = ekmFromMasterSecret(c.vers, hs.suite, hs.masterSecret, hs.hello.random, hs.serverHello.random)
+	atomic.StoreUint32(&c.handshakeStatus, 1)
+
+	return nil
+}
+
+func (hs *clientHandshakeState) pickCipherSuite() error {
+	if hs.suite = mutualCipherSuite(hs.hello.cipherSuites, hs.serverHello.cipherSuite); hs.suite == nil {
+		hs.c.sendAlert(alertHandshakeFailure)
+		return errors.New("tls: server chose an unconfigured cipher suite")
+	}
+
+	hs.c.cipherSuite = hs.suite.id
+	return nil
+}
+
+func (hs *clientHandshakeState) doFullHandshake() error {
+	c := hs.c
+
+	msg, err := c.readHandshake()
+	if err != nil {
+		return err
+	}
+	certMsg, ok := msg.(*certificateMsg)
+	if !ok || len(certMsg.certificates) == 0 {
+		c.sendAlert(alertUnexpectedMessage)
+		return unexpectedMessageError(certMsg, msg)
+	}
+	hs.finishedHash.Write(certMsg.marshal())
+
+	msg, err = c.readHandshake()
+	if err != nil {
+		return err
+	}
+
+	cs, ok := msg.(*certificateStatusMsg)
+	if ok {
+		// RFC4366 on Certificate Status Request:
+		// The server MAY return a "certificate_status" message.
+
+		if !hs.serverHello.ocspStapling {
+			// If a server returns a "CertificateStatus" message, then the
+			// server MUST have included an extension of type "status_request"
+			// with empty "extension_data" in the extended server hello.
+
+			c.sendAlert(alertUnexpectedMessage)
+			return errors.New("tls: received unexpected CertificateStatus message")
+		}
+		hs.finishedHash.Write(cs.marshal())
+
+		c.ocspResponse = cs.response
+
+		msg, err = c.readHandshake()
+		if err != nil {
+			return err
+		}
+	}
+
+	if c.handshakes == 0 {
+		// If this is the first handshake on a connection, process and
+		// (optionally) verify the server's certificates.
+		if err := c.verifyServerCertificate(certMsg.certificates); err != nil {
+			return err
+		}
+	} else {
+		// This is a renegotiation handshake. We require that the
+		// server's identity (i.e. leaf certificate) is unchanged and
+		// thus any previous trust decision is still valid.
+		//
+		// See https://mitls.org/pages/attacks/3SHAKE for the
+		// motivation behind this requirement.
+		if !bytes.Equal(c.peerCertificates[0].Raw, certMsg.certificates[0]) {
+			c.sendAlert(alertBadCertificate)
+			return errors.New("tls: server's identity changed during renegotiation")
+		}
+	}
+
+	keyAgreement := hs.suite.ka(c.vers)
+
+	skx, ok := msg.(*serverKeyExchangeMsg)
+	if ok {
+		hs.finishedHash.Write(skx.marshal())
+		err = keyAgreement.processServerKeyExchange(c.config, hs.hello, hs.serverHello, c.peerCertificates[0], skx)
+		if err != nil {
+			c.sendAlert(alertUnexpectedMessage)
+			return err
+		}
+
+		msg, err = c.readHandshake()
+		if err != nil {
+			return err
+		}
+	}
+
+	var chainToSend *Certificate
+	var certRequested bool
+	certReq, ok := msg.(*certificateRequestMsg)
+	if ok {
+		certRequested = true
+		hs.finishedHash.Write(certReq.marshal())
+
+		cri := certificateRequestInfoFromMsg(hs.ctx, c.vers, certReq)
+		if chainToSend, err = c.getClientCertificate(cri); err != nil {
+			c.sendAlert(alertInternalError)
+			return err
+		}
+
+		msg, err = c.readHandshake()
+		if err != nil {
+			return err
+		}
+	}
+
+	shd, ok := msg.(*serverHelloDoneMsg)
+	if !ok {
+		c.sendAlert(alertUnexpectedMessage)
+		return unexpectedMessageError(shd, msg)
+	}
+	hs.finishedHash.Write(shd.marshal())
+
+	// If the server requested a certificate then we have to send a
+	// Certificate message, even if it's empty because we don't have a
+	// certificate to send.
+	if certRequested {
+		certMsg = new(certificateMsg)
+		certMsg.certificates = chainToSend.Certificate
+		hs.finishedHash.Write(certMsg.marshal())
+		if _, err := c.writeRecord(recordTypeHandshake, certMsg.marshal()); err != nil {
+			return err
+		}
+	}
+
+	preMasterSecret, ckx, err := keyAgreement.generateClientKeyExchange(c.config, hs.hello, c.peerCertificates[0])
+	if err != nil {
+		c.sendAlert(alertInternalError)
+		return err
+	}
+	if ckx != nil {
+		hs.finishedHash.Write(ckx.marshal())
+		if _, err := c.writeRecord(recordTypeHandshake, ckx.marshal()); err != nil {
+			return err
+		}
+	}
+
+	if chainToSend != nil && len(chainToSend.Certificate) > 0 {
+		certVerify := &certificateVerifyMsg{}
+
+		key, ok := chainToSend.PrivateKey.(crypto.Signer)
+		if !ok {
+			c.sendAlert(alertInternalError)
+			return fmt.Errorf("tls: client certificate private key of type %T does not implement crypto.Signer", chainToSend.PrivateKey)
+		}
+
+		var sigType uint8
+		var sigHash crypto.Hash
+		if c.vers >= VersionTLS12 {
+			signatureAlgorithm, err := selectSignatureScheme(c.vers, chainToSend, certReq.supportedSignatureAlgorithms)
+			if err != nil {
+				c.sendAlert(alertIllegalParameter)
+				return err
+			}
+			sigType, sigHash, err = typeAndHashFromSignatureScheme(signatureAlgorithm)
+			if err != nil {
+				return c.sendAlert(alertInternalError)
+			}
+			certVerify.hasSignatureAlgorithm = true
+			certVerify.signatureAlgorithm = signatureAlgorithm
+		} else {
+			sigType, sigHash, err = legacyTypeAndHashFromPublicKey(key.Public())
+			if err != nil {
+				c.sendAlert(alertIllegalParameter)
+				return err
+			}
+		}
+
+		signed := hs.finishedHash.hashForClientCertificate(sigType, sigHash, hs.masterSecret)
+		signOpts := crypto.SignerOpts(sigHash)
+		if sigType == signatureRSAPSS {
+			signOpts = &rsa.PSSOptions{SaltLength: rsa.PSSSaltLengthEqualsHash, Hash: sigHash}
+		}
+		certVerify.signature, err = key.Sign(c.config.rand(), signed, signOpts)
+		if err != nil {
+			c.sendAlert(alertInternalError)
+			return err
+		}
+
+		hs.finishedHash.Write(certVerify.marshal())
+		if _, err := c.writeRecord(recordTypeHandshake, certVerify.marshal()); err != nil {
+			return err
+		}
+	}
+
+	hs.masterSecret = masterFromPreMasterSecret(c.vers, hs.suite, preMasterSecret, hs.hello.random, hs.serverHello.random)
+	if err := c.config.writeKeyLog(keyLogLabelTLS12, hs.hello.random, hs.masterSecret); err != nil {
+		c.sendAlert(alertInternalError)
+		return errors.New("tls: failed to write to key log: " + err.Error())
+	}
+
+	hs.finishedHash.discardHandshakeBuffer()
+
+	return nil
+}
+
+func (hs *clientHandshakeState) establishKeys() error {
+	c := hs.c
+
+	clientMAC, serverMAC, clientKey, serverKey, clientIV, serverIV :=
+		keysFromMasterSecret(c.vers, hs.suite, hs.masterSecret, hs.hello.random, hs.serverHello.random, hs.suite.macLen, hs.suite.keyLen, hs.suite.ivLen)
+	var clientCipher, serverCipher any
+	var clientHash, serverHash hash.Hash
+	if hs.suite.cipher != nil {
+		clientCipher = hs.suite.cipher(clientKey, clientIV, false /* not for reading */)
+		clientHash = hs.suite.mac(clientMAC)
+		serverCipher = hs.suite.cipher(serverKey, serverIV, true /* for reading */)
+		serverHash = hs.suite.mac(serverMAC)
+	} else {
+		clientCipher = hs.suite.aead(clientKey, clientIV)
+		serverCipher = hs.suite.aead(serverKey, serverIV)
+	}
+
+	c.in.prepareCipherSpec(c.vers, serverCipher, serverHash)
+	c.out.prepareCipherSpec(c.vers, clientCipher, clientHash)
+	return nil
+}
+
+func (hs *clientHandshakeState) serverResumedSession() bool {
+	// If the server responded with the same sessionId then it means the
+	// sessionTicket is being used to resume a TLS session.
+	return hs.session != nil && hs.hello.sessionId != nil &&
+		bytes.Equal(hs.serverHello.sessionId, hs.hello.sessionId)
+}
+
+func (hs *clientHandshakeState) processServerHello() (bool, error) {
+	c := hs.c
+
+	if err := hs.pickCipherSuite(); err != nil {
+		return false, err
+	}
+
+	if hs.serverHello.compressionMethod != compressionNone {
+		c.sendAlert(alertUnexpectedMessage)
+		return false, errors.New("tls: server selected unsupported compression format")
+	}
+
+	if c.handshakes == 0 && hs.serverHello.secureRenegotiationSupported {
+		c.secureRenegotiation = true
+		if len(hs.serverHello.secureRenegotiation) != 0 {
+			c.sendAlert(alertHandshakeFailure)
+			return false, errors.New("tls: initial handshake had non-empty renegotiation extension")
+		}
+	}
+
+	if c.handshakes > 0 && c.secureRenegotiation {
+		var expectedSecureRenegotiation [24]byte
+		copy(expectedSecureRenegotiation[:], c.clientFinished[:])
+		copy(expectedSecureRenegotiation[12:], c.serverFinished[:])
+		if !bytes.Equal(hs.serverHello.secureRenegotiation, expectedSecureRenegotiation[:]) {
+			c.sendAlert(alertHandshakeFailure)
+			return false, errors.New("tls: incorrect renegotiation extension contents")
+		}
+	}
+
+	if err := checkALPN(hs.hello.alpnProtocols, hs.serverHello.alpnProtocol); err != nil {
+		c.sendAlert(alertUnsupportedExtension)
+		return false, err
+	}
+	c.clientProtocol = hs.serverHello.alpnProtocol
+
+	c.scts = hs.serverHello.scts
+
+	if !hs.serverResumedSession() {
+		return false, nil
+	}
+
+	if hs.session.vers != c.vers {
+		c.sendAlert(alertHandshakeFailure)
+		return false, errors.New("tls: server resumed a session with a different version")
+	}
+
+	if hs.session.cipherSuite != hs.suite.id {
+		c.sendAlert(alertHandshakeFailure)
+		return false, errors.New("tls: server resumed a session with a different cipher suite")
+	}
+
+	// Restore masterSecret, peerCerts, and ocspResponse from previous state
+	hs.masterSecret = hs.session.masterSecret
+	c.peerCertificates = hs.session.serverCertificates
+	c.verifiedChains = hs.session.verifiedChains
+	c.ocspResponse = hs.session.ocspResponse
+	// Let the ServerHello SCTs override the session SCTs from the original
+	// connection, if any are provided
+	if len(c.scts) == 0 && len(hs.session.scts) != 0 {
+		c.scts = hs.session.scts
+	}
+
+	return true, nil
+}
+
+// checkALPN ensure that the server's choice of ALPN protocol is compatible with
+// the protocols that we advertised in the Client Hello.
+func checkALPN(clientProtos []string, serverProto string) error {
+	if serverProto == "" {
+		return nil
+	}
+	if len(clientProtos) == 0 {
+		return errors.New("tls: server advertised unrequested ALPN extension")
+	}
+	for _, proto := range clientProtos {
+		if proto == serverProto {
+			return nil
+		}
+	}
+	return errors.New("tls: server selected unadvertised ALPN protocol")
+}
+
+func (hs *clientHandshakeState) readFinished(out []byte) error {
+	c := hs.c
+
+	if err := c.readChangeCipherSpec(); err != nil {
+		return err
+	}
+
+	msg, err := c.readHandshake()
+	if err != nil {
+		return err
+	}
+	serverFinished, ok := msg.(*finishedMsg)
+	if !ok {
+		c.sendAlert(alertUnexpectedMessage)
+		return unexpectedMessageError(serverFinished, msg)
+	}
+
+	verify := hs.finishedHash.serverSum(hs.masterSecret)
+	if len(verify) != len(serverFinished.verifyData) ||
+		subtle.ConstantTimeCompare(verify, serverFinished.verifyData) != 1 {
+		c.sendAlert(alertHandshakeFailure)
+		return errors.New("tls: server's Finished message was incorrect")
+	}
+	hs.finishedHash.Write(serverFinished.marshal())
+	copy(out, verify)
+	return nil
+}
+
+func (hs *clientHandshakeState) readSessionTicket() error {
+	if !hs.serverHello.ticketSupported {
+		return nil
+	}
+
+	c := hs.c
+	msg, err := c.readHandshake()
+	if err != nil {
+		return err
+	}
+	sessionTicketMsg, ok := msg.(*newSessionTicketMsg)
+	if !ok {
+		c.sendAlert(alertUnexpectedMessage)
+		return unexpectedMessageError(sessionTicketMsg, msg)
+	}
+	hs.finishedHash.Write(sessionTicketMsg.marshal())
+
+	hs.session = &ClientSessionState{
+		sessionTicket:      sessionTicketMsg.ticket,
+		vers:               c.vers,
+		cipherSuite:        hs.suite.id,
+		masterSecret:       hs.masterSecret,
+		serverCertificates: c.peerCertificates,
+		verifiedChains:     c.verifiedChains,
+		receivedAt:         c.config.time(),
+		ocspResponse:       c.ocspResponse,
+		scts:               c.scts,
+	}
+
+	return nil
+}
+
+func (hs *clientHandshakeState) sendFinished(out []byte) error {
+	c := hs.c
+
+	if _, err := c.writeRecord(recordTypeChangeCipherSpec, []byte{1}); err != nil {
+		return err
+	}
+
+	finished := new(finishedMsg)
+	finished.verifyData = hs.finishedHash.clientSum(hs.masterSecret)
+	hs.finishedHash.Write(finished.marshal())
+	if _, err := c.writeRecord(recordTypeHandshake, finished.marshal()); err != nil {
+		return err
+	}
+	copy(out, finished.verifyData)
+	return nil
+}
+
+// verifyServerCertificate parses and verifies the provided chain, setting
+// c.verifiedChains and c.peerCertificates or sending the appropriate alert.
+func (c *Conn) verifyServerCertificate(certificates [][]byte) error {
+	certs := make([]*x509.Certificate, len(certificates))
+	for i, asn1Data := range certificates {
+		cert, err := x509.ParseCertificate(asn1Data)
+		if err != nil {
+			c.sendAlert(alertBadCertificate)
+			return errors.New("tls: failed to parse certificate from server: " + err.Error())
+		}
+		certs[i] = cert
+	}
+
+	if !c.config.InsecureSkipVerify {
+		opts := x509.VerifyOptions{
+			Roots:         c.config.RootCAs,
+			CurrentTime:   c.config.time(),
+			DNSName:       c.config.ServerName,
+			Intermediates: x509.NewCertPool(),
+		}
+
+		for _, cert := range certs[1:] {
+			opts.Intermediates.AddCert(cert)
+		}
+		var err error
+		c.verifiedChains, err = certs[0].Verify(opts)
+		if err != nil {
+			c.sendAlert(alertBadCertificate)
+			return err
+		}
+	}
+
+	switch certs[0].PublicKey.(type) {
+	case *rsa.PublicKey, *ecdsa.PublicKey, ed25519.PublicKey:
+		break
+	default:
+		c.sendAlert(alertUnsupportedCertificate)
+		return fmt.Errorf("tls: server's certificate contains an unsupported type of public key: %T", certs[0].PublicKey)
+	}
+
+	c.peerCertificates = certs
+
+	if c.config.VerifyPeerCertificate != nil {
+		if err := c.config.VerifyPeerCertificate(certificates, c.verifiedChains); err != nil {
+			c.sendAlert(alertBadCertificate)
+			return err
+		}
+	}
+
+	if c.config.VerifyConnection != nil {
+		if err := c.config.VerifyConnection(c.connectionStateLocked()); err != nil {
+			c.sendAlert(alertBadCertificate)
+			return err
+		}
+	}
+
+	return nil
+}
+
+// certificateRequestInfoFromMsg generates a CertificateRequestInfo from a TLS
+// <= 1.2 CertificateRequest, making an effort to fill in missing information.
+func certificateRequestInfoFromMsg(ctx context.Context, vers uint16, certReq *certificateRequestMsg) *CertificateRequestInfo {
+	cri := &CertificateRequestInfo{
+		AcceptableCAs: certReq.certificateAuthorities,
+		Version:       vers,
+		ctx:           ctx,
+	}
+
+	var rsaAvail, ecAvail bool
+	for _, certType := range certReq.certificateTypes {
+		switch certType {
+		case certTypeRSASign:
+			rsaAvail = true
+		case certTypeECDSASign:
+			ecAvail = true
+		}
+	}
+
+	if !certReq.hasSignatureAlgorithm {
+		// Prior to TLS 1.2, signature schemes did not exist. In this case we
+		// make up a list based on the acceptable certificate types, to help
+		// GetClientCertificate and SupportsCertificate select the right certificate.
+		// The hash part of the SignatureScheme is a lie here, because
+		// TLS 1.0 and 1.1 always use MD5+SHA1 for RSA and SHA1 for ECDSA.
+		switch {
+		case rsaAvail && ecAvail:
+			cri.SignatureSchemes = []SignatureScheme{
+				ECDSAWithP256AndSHA256, ECDSAWithP384AndSHA384, ECDSAWithP521AndSHA512,
+				PKCS1WithSHA256, PKCS1WithSHA384, PKCS1WithSHA512, PKCS1WithSHA1,
+			}
+		case rsaAvail:
+			cri.SignatureSchemes = []SignatureScheme{
+				PKCS1WithSHA256, PKCS1WithSHA384, PKCS1WithSHA512, PKCS1WithSHA1,
+			}
+		case ecAvail:
+			cri.SignatureSchemes = []SignatureScheme{
+				ECDSAWithP256AndSHA256, ECDSAWithP384AndSHA384, ECDSAWithP521AndSHA512,
+			}
+		}
+		return cri
+	}
+
+	// Filter the signature schemes based on the certificate types.
+	// See RFC 5246, Section 7.4.4 (where it calls this "somewhat complicated").
+	cri.SignatureSchemes = make([]SignatureScheme, 0, len(certReq.supportedSignatureAlgorithms))
+	for _, sigScheme := range certReq.supportedSignatureAlgorithms {
+		sigType, _, err := typeAndHashFromSignatureScheme(sigScheme)
+		if err != nil {
+			continue
+		}
+		switch sigType {
+		case signatureECDSA, signatureEd25519:
+			if ecAvail {
+				cri.SignatureSchemes = append(cri.SignatureSchemes, sigScheme)
+			}
+		case signatureRSAPSS, signaturePKCS1v15:
+			if rsaAvail {
+				cri.SignatureSchemes = append(cri.SignatureSchemes, sigScheme)
+			}
+		}
+	}
+
+	return cri
+}
+
+func (c *Conn) getClientCertificate(cri *CertificateRequestInfo) (*Certificate, error) {
+	if c.config.GetClientCertificate != nil {
+		return c.config.GetClientCertificate(cri)
+	}
+
+	for _, chain := range c.config.Certificates {
+		if err := cri.SupportsCertificate(&chain); err != nil {
+			continue
+		}
+		return &chain, nil
+	}
+
+	// No acceptable certificate found. Don't send a certificate.
+	return new(Certificate), nil
+}
+
+// clientSessionCacheKey returns a key used to cache sessionTickets that could
+// be used to resume previously negotiated TLS sessions with a server.
+func clientSessionCacheKey(serverAddr net.Addr, config *Config) string {
+	if len(config.ServerName) > 0 {
+		return config.ServerName
+	}
+	return serverAddr.String()
+}
+
+// hostnameInSNI converts name into an appropriate hostname for SNI.
+// Literal IP addresses and absolute FQDNs are not permitted as SNI values.
+// See RFC 6066, Section 3.
+func hostnameInSNI(name string) string {
+	host := name
+	if len(host) > 0 && host[0] == '[' && host[len(host)-1] == ']' {
+		host = host[1 : len(host)-1]
+	}
+	if i := strings.LastIndex(host, "%"); i > 0 {
+		host = host[:i]
+	}
+	if net.ParseIP(host) != nil {
+		return ""
+	}
+	for len(name) > 0 && name[len(name)-1] == '.' {
+		name = name[:len(name)-1]
+	}
+	return name
+}
diff --git a/contrib/go/_std_1.19/src/crypto/tls/handshake_client_tls13.go b/contrib/go/_std_1.19/src/crypto/tls/handshake_client_tls13.go
new file mode 100644
index 0000000000..c7989867f5
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/tls/handshake_client_tls13.go
@@ -0,0 +1,686 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package tls
+
+import (
+	"bytes"
+	"context"
+	"crypto"
+	"crypto/hmac"
+	"crypto/rsa"
+	"errors"
+	"hash"
+	"sync/atomic"
+	"time"
+)
+
+type clientHandshakeStateTLS13 struct {
+	c           *Conn
+	ctx         context.Context
+	serverHello *serverHelloMsg
+	hello       *clientHelloMsg
+	ecdheParams ecdheParameters
+
+	session     *ClientSessionState
+	earlySecret []byte
+	binderKey   []byte
+
+	certReq       *certificateRequestMsgTLS13
+	usingPSK      bool
+	sentDummyCCS  bool
+	suite         *cipherSuiteTLS13
+	transcript    hash.Hash
+	masterSecret  []byte
+	trafficSecret []byte // client_application_traffic_secret_0
+}
+
+// handshake requires hs.c, hs.hello, hs.serverHello, hs.ecdheParams, and,
+// optionally, hs.session, hs.earlySecret and hs.binderKey to be set.
+func (hs *clientHandshakeStateTLS13) handshake() error {
+	c := hs.c
+
+	if needFIPS() {
+		return errors.New("tls: internal error: TLS 1.3 reached in FIPS mode")
+	}
+
+	// The server must not select TLS 1.3 in a renegotiation. See RFC 8446,
+	// sections 4.1.2 and 4.1.3.
+	if c.handshakes > 0 {
+		c.sendAlert(alertProtocolVersion)
+		return errors.New("tls: server selected TLS 1.3 in a renegotiation")
+	}
+
+	// Consistency check on the presence of a keyShare and its parameters.
+	if hs.ecdheParams == nil || len(hs.hello.keyShares) != 1 {
+		return c.sendAlert(alertInternalError)
+	}
+
+	if err := hs.checkServerHelloOrHRR(); err != nil {
+		return err
+	}
+
+	hs.transcript = hs.suite.hash.New()
+	hs.transcript.Write(hs.hello.marshal())
+
+	if bytes.Equal(hs.serverHello.random, helloRetryRequestRandom) {
+		if err := hs.sendDummyChangeCipherSpec(); err != nil {
+			return err
+		}
+		if err := hs.processHelloRetryRequest(); err != nil {
+			return err
+		}
+	}
+
+	hs.transcript.Write(hs.serverHello.marshal())
+
+	c.buffering = true
+	if err := hs.processServerHello(); err != nil {
+		return err
+	}
+	if err := hs.sendDummyChangeCipherSpec(); err != nil {
+		return err
+	}
+	if err := hs.establishHandshakeKeys(); err != nil {
+		return err
+	}
+	if err := hs.readServerParameters(); err != nil {
+		return err
+	}
+	if err := hs.readServerCertificate(); err != nil {
+		return err
+	}
+	if err := hs.readServerFinished(); err != nil {
+		return err
+	}
+	if err := hs.sendClientCertificate(); err != nil {
+		return err
+	}
+	if err := hs.sendClientFinished(); err != nil {
+		return err
+	}
+	if _, err := c.flush(); err != nil {
+		return err
+	}
+
+	atomic.StoreUint32(&c.handshakeStatus, 1)
+
+	return nil
+}
+
+// checkServerHelloOrHRR does validity checks that apply to both ServerHello and
+// HelloRetryRequest messages. It sets hs.suite.
+func (hs *clientHandshakeStateTLS13) checkServerHelloOrHRR() error {
+	c := hs.c
+
+	if hs.serverHello.supportedVersion == 0 {
+		c.sendAlert(alertMissingExtension)
+		return errors.New("tls: server selected TLS 1.3 using the legacy version field")
+	}
+
+	if hs.serverHello.supportedVersion != VersionTLS13 {
+		c.sendAlert(alertIllegalParameter)
+		return errors.New("tls: server selected an invalid version after a HelloRetryRequest")
+	}
+
+	if hs.serverHello.vers != VersionTLS12 {
+		c.sendAlert(alertIllegalParameter)
+		return errors.New("tls: server sent an incorrect legacy version")
+	}
+
+	if hs.serverHello.ocspStapling ||
+		hs.serverHello.ticketSupported ||
+		hs.serverHello.secureRenegotiationSupported ||
+		len(hs.serverHello.secureRenegotiation) != 0 ||
+		len(hs.serverHello.alpnProtocol) != 0 ||
+		len(hs.serverHello.scts) != 0 {
+		c.sendAlert(alertUnsupportedExtension)
+		return errors.New("tls: server sent a ServerHello extension forbidden in TLS 1.3")
+	}
+
+	if !bytes.Equal(hs.hello.sessionId, hs.serverHello.sessionId) {
+		c.sendAlert(alertIllegalParameter)
+		return errors.New("tls: server did not echo the legacy session ID")
+	}
+
+	if hs.serverHello.compressionMethod != compressionNone {
+		c.sendAlert(alertIllegalParameter)
+		return errors.New("tls: server selected unsupported compression format")
+	}
+
+	selectedSuite := mutualCipherSuiteTLS13(hs.hello.cipherSuites, hs.serverHello.cipherSuite)
+	if hs.suite != nil && selectedSuite != hs.suite {
+		c.sendAlert(alertIllegalParameter)
+		return errors.New("tls: server changed cipher suite after a HelloRetryRequest")
+	}
+	if selectedSuite == nil {
+		c.sendAlert(alertIllegalParameter)
+		return errors.New("tls: server chose an unconfigured cipher suite")
+	}
+	hs.suite = selectedSuite
+	c.cipherSuite = hs.suite.id
+
+	return nil
+}
+
+// sendDummyChangeCipherSpec sends a ChangeCipherSpec record for compatibility
+// with middleboxes that didn't implement TLS correctly. See RFC 8446, Appendix D.4.
+func (hs *clientHandshakeStateTLS13) sendDummyChangeCipherSpec() error {
+	if hs.sentDummyCCS {
+		return nil
+	}
+	hs.sentDummyCCS = true
+
+	_, err := hs.c.writeRecord(recordTypeChangeCipherSpec, []byte{1})
+	return err
+}
+
+// processHelloRetryRequest handles the HRR in hs.serverHello, modifies and
+// resends hs.hello, and reads the new ServerHello into hs.serverHello.
+func (hs *clientHandshakeStateTLS13) processHelloRetryRequest() error {
+	c := hs.c
+
+	// The first ClientHello gets double-hashed into the transcript upon a
+	// HelloRetryRequest. (The idea is that the server might offload transcript
+	// storage to the client in the cookie.) See RFC 8446, Section 4.4.1.
+	chHash := hs.transcript.Sum(nil)
+	hs.transcript.Reset()
+	hs.transcript.Write([]byte{typeMessageHash, 0, 0, uint8(len(chHash))})
+	hs.transcript.Write(chHash)
+	hs.transcript.Write(hs.serverHello.marshal())
+
+	// The only HelloRetryRequest extensions we support are key_share and
+	// cookie, and clients must abort the handshake if the HRR would not result
+	// in any change in the ClientHello.
+	if hs.serverHello.selectedGroup == 0 && hs.serverHello.cookie == nil {
+		c.sendAlert(alertIllegalParameter)
+		return errors.New("tls: server sent an unnecessary HelloRetryRequest message")
+	}
+
+	if hs.serverHello.cookie != nil {
+		hs.hello.cookie = hs.serverHello.cookie
+	}
+
+	if hs.serverHello.serverShare.group != 0 {
+		c.sendAlert(alertDecodeError)
+		return errors.New("tls: received malformed key_share extension")
+	}
+
+	// If the server sent a key_share extension selecting a group, ensure it's
+	// a group we advertised but did not send a key share for, and send a key
+	// share for it this time.
+	if curveID := hs.serverHello.selectedGroup; curveID != 0 {
+		curveOK := false
+		for _, id := range hs.hello.supportedCurves {
+			if id == curveID {
+				curveOK = true
+				break
+			}
+		}
+		if !curveOK {
+			c.sendAlert(alertIllegalParameter)
+			return errors.New("tls: server selected unsupported group")
+		}
+		if hs.ecdheParams.CurveID() == curveID {
+			c.sendAlert(alertIllegalParameter)
+			return errors.New("tls: server sent an unnecessary HelloRetryRequest key_share")
+		}
+		if _, ok := curveForCurveID(curveID); curveID != X25519 && !ok {
+			c.sendAlert(alertInternalError)
+			return errors.New("tls: CurvePreferences includes unsupported curve")
+		}
+		params, err := generateECDHEParameters(c.config.rand(), curveID)
+		if err != nil {
+			c.sendAlert(alertInternalError)
+			return err
+		}
+		hs.ecdheParams = params
+		hs.hello.keyShares = []keyShare{{group: curveID, data: params.PublicKey()}}
+	}
+
+	hs.hello.raw = nil
+	if len(hs.hello.pskIdentities) > 0 {
+		pskSuite := cipherSuiteTLS13ByID(hs.session.cipherSuite)
+		if pskSuite == nil {
+			return c.sendAlert(alertInternalError)
+		}
+		if pskSuite.hash == hs.suite.hash {
+			// Update binders and obfuscated_ticket_age.
+			ticketAge := uint32(c.config.time().Sub(hs.session.receivedAt) / time.Millisecond)
+			hs.hello.pskIdentities[0].obfuscatedTicketAge = ticketAge + hs.session.ageAdd
+
+			transcript := hs.suite.hash.New()
+			transcript.Write([]byte{typeMessageHash, 0, 0, uint8(len(chHash))})
+			transcript.Write(chHash)
+			transcript.Write(hs.serverHello.marshal())
+			transcript.Write(hs.hello.marshalWithoutBinders())
+			pskBinders := [][]byte{hs.suite.finishedHash(hs.binderKey, transcript)}
+			hs.hello.updateBinders(pskBinders)
+		} else {
+			// Server selected a cipher suite incompatible with the PSK.
+			hs.hello.pskIdentities = nil
+			hs.hello.pskBinders = nil
+		}
+	}
+
+	hs.transcript.Write(hs.hello.marshal())
+	if _, err := c.writeRecord(recordTypeHandshake, hs.hello.marshal()); err != nil {
+		return err
+	}
+
+	msg, err := c.readHandshake()
+	if err != nil {
+		return err
+	}
+
+	serverHello, ok := msg.(*serverHelloMsg)
+	if !ok {
+		c.sendAlert(alertUnexpectedMessage)
+		return unexpectedMessageError(serverHello, msg)
+	}
+	hs.serverHello = serverHello
+
+	if err := hs.checkServerHelloOrHRR(); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (hs *clientHandshakeStateTLS13) processServerHello() error {
+	c := hs.c
+
+	if bytes.Equal(hs.serverHello.random, helloRetryRequestRandom) {
+		c.sendAlert(alertUnexpectedMessage)
+		return errors.New("tls: server sent two HelloRetryRequest messages")
+	}
+
+	if len(hs.serverHello.cookie) != 0 {
+		c.sendAlert(alertUnsupportedExtension)
+		return errors.New("tls: server sent a cookie in a normal ServerHello")
+	}
+
+	if hs.serverHello.selectedGroup != 0 {
+		c.sendAlert(alertDecodeError)
+		return errors.New("tls: malformed key_share extension")
+	}
+
+	if hs.serverHello.serverShare.group == 0 {
+		c.sendAlert(alertIllegalParameter)
+		return errors.New("tls: server did not send a key share")
+	}
+	if hs.serverHello.serverShare.group != hs.ecdheParams.CurveID() {
+		c.sendAlert(alertIllegalParameter)
+		return errors.New("tls: server selected unsupported group")
+	}
+
+	if !hs.serverHello.selectedIdentityPresent {
+		return nil
+	}
+
+	if int(hs.serverHello.selectedIdentity) >= len(hs.hello.pskIdentities) {
+		c.sendAlert(alertIllegalParameter)
+		return errors.New("tls: server selected an invalid PSK")
+	}
+
+	if len(hs.hello.pskIdentities) != 1 || hs.session == nil {
+		return c.sendAlert(alertInternalError)
+	}
+	pskSuite := cipherSuiteTLS13ByID(hs.session.cipherSuite)
+	if pskSuite == nil {
+		return c.sendAlert(alertInternalError)
+	}
+	if pskSuite.hash != hs.suite.hash {
+		c.sendAlert(alertIllegalParameter)
+		return errors.New("tls: server selected an invalid PSK and cipher suite pair")
+	}
+
+	hs.usingPSK = true
+	c.didResume = true
+	c.peerCertificates = hs.session.serverCertificates
+	c.verifiedChains = hs.session.verifiedChains
+	c.ocspResponse = hs.session.ocspResponse
+	c.scts = hs.session.scts
+	return nil
+}
+
+func (hs *clientHandshakeStateTLS13) establishHandshakeKeys() error {
+	c := hs.c
+
+	sharedKey := hs.ecdheParams.SharedKey(hs.serverHello.serverShare.data)
+	if sharedKey == nil {
+		c.sendAlert(alertIllegalParameter)
+		return errors.New("tls: invalid server key share")
+	}
+
+	earlySecret := hs.earlySecret
+	if !hs.usingPSK {
+		earlySecret = hs.suite.extract(nil, nil)
+	}
+	handshakeSecret := hs.suite.extract(sharedKey,
+		hs.suite.deriveSecret(earlySecret, "derived", nil))
+
+	clientSecret := hs.suite.deriveSecret(handshakeSecret,
+		clientHandshakeTrafficLabel, hs.transcript)
+	c.out.setTrafficSecret(hs.suite, clientSecret)
+	serverSecret := hs.suite.deriveSecret(handshakeSecret,
+		serverHandshakeTrafficLabel, hs.transcript)
+	c.in.setTrafficSecret(hs.suite, serverSecret)
+
+	err := c.config.writeKeyLog(keyLogLabelClientHandshake, hs.hello.random, clientSecret)
+	if err != nil {
+		c.sendAlert(alertInternalError)
+		return err
+	}
+	err = c.config.writeKeyLog(keyLogLabelServerHandshake, hs.hello.random, serverSecret)
+	if err != nil {
+		c.sendAlert(alertInternalError)
+		return err
+	}
+
+	hs.masterSecret = hs.suite.extract(nil,
+		hs.suite.deriveSecret(handshakeSecret, "derived", nil))
+
+	return nil
+}
+
+func (hs *clientHandshakeStateTLS13) readServerParameters() error {
+	c := hs.c
+
+	msg, err := c.readHandshake()
+	if err != nil {
+		return err
+	}
+
+	encryptedExtensions, ok := msg.(*encryptedExtensionsMsg)
+	if !ok {
+		c.sendAlert(alertUnexpectedMessage)
+		return unexpectedMessageError(encryptedExtensions, msg)
+	}
+	hs.transcript.Write(encryptedExtensions.marshal())
+
+	if err := checkALPN(hs.hello.alpnProtocols, encryptedExtensions.alpnProtocol); err != nil {
+		c.sendAlert(alertUnsupportedExtension)
+		return err
+	}
+	c.clientProtocol = encryptedExtensions.alpnProtocol
+
+	return nil
+}
+
+func (hs *clientHandshakeStateTLS13) readServerCertificate() error {
+	c := hs.c
+
+	// Either a PSK or a certificate is always used, but not both.
+	// See RFC 8446, Section 4.1.1.
+	if hs.usingPSK {
+		// Make sure the connection is still being verified whether or not this
+		// is a resumption. Resumptions currently don't reverify certificates so
+		// they don't call verifyServerCertificate. See Issue 31641.
+		if c.config.VerifyConnection != nil {
+			if err := c.config.VerifyConnection(c.connectionStateLocked()); err != nil {
+				c.sendAlert(alertBadCertificate)
+				return err
+			}
+		}
+		return nil
+	}
+
+	msg, err := c.readHandshake()
+	if err != nil {
+		return err
+	}
+
+	certReq, ok := msg.(*certificateRequestMsgTLS13)
+	if ok {
+		hs.transcript.Write(certReq.marshal())
+
+		hs.certReq = certReq
+
+		msg, err = c.readHandshake()
+		if err != nil {
+			return err
+		}
+	}
+
+	certMsg, ok := msg.(*certificateMsgTLS13)
+	if !ok {
+		c.sendAlert(alertUnexpectedMessage)
+		return unexpectedMessageError(certMsg, msg)
+	}
+	if len(certMsg.certificate.Certificate) == 0 {
+		c.sendAlert(alertDecodeError)
+		return errors.New("tls: received empty certificates message")
+	}
+	hs.transcript.Write(certMsg.marshal())
+
+	c.scts = certMsg.certificate.SignedCertificateTimestamps
+	c.ocspResponse = certMsg.certificate.OCSPStaple
+
+	if err := c.verifyServerCertificate(certMsg.certificate.Certificate); err != nil {
+		return err
+	}
+
+	msg, err = c.readHandshake()
+	if err != nil {
+		return err
+	}
+
+	certVerify, ok := msg.(*certificateVerifyMsg)
+	if !ok {
+		c.sendAlert(alertUnexpectedMessage)
+		return unexpectedMessageError(certVerify, msg)
+	}
+
+	// See RFC 8446, Section 4.4.3.
+	if !isSupportedSignatureAlgorithm(certVerify.signatureAlgorithm, supportedSignatureAlgorithms()) {
+		c.sendAlert(alertIllegalParameter)
+		return errors.New("tls: certificate used with invalid signature algorithm")
+	}
+	sigType, sigHash, err := typeAndHashFromSignatureScheme(certVerify.signatureAlgorithm)
+	if err != nil {
+		return c.sendAlert(alertInternalError)
+	}
+	if sigType == signaturePKCS1v15 || sigHash == crypto.SHA1 {
+		c.sendAlert(alertIllegalParameter)
+		return errors.New("tls: certificate used with invalid signature algorithm")
+	}
+	signed := signedMessage(sigHash, serverSignatureContext, hs.transcript)
+	if err := verifyHandshakeSignature(sigType, c.peerCertificates[0].PublicKey,
+		sigHash, signed, certVerify.signature); err != nil {
+		c.sendAlert(alertDecryptError)
+		return errors.New("tls: invalid signature by the server certificate: " + err.Error())
+	}
+
+	hs.transcript.Write(certVerify.marshal())
+
+	return nil
+}
+
+func (hs *clientHandshakeStateTLS13) readServerFinished() error {
+	c := hs.c
+
+	msg, err := c.readHandshake()
+	if err != nil {
+		return err
+	}
+
+	finished, ok := msg.(*finishedMsg)
+	if !ok {
+		c.sendAlert(alertUnexpectedMessage)
+		return unexpectedMessageError(finished, msg)
+	}
+
+	expectedMAC := hs.suite.finishedHash(c.in.trafficSecret, hs.transcript)
+	if !hmac.Equal(expectedMAC, finished.verifyData) {
+		c.sendAlert(alertDecryptError)
+		return errors.New("tls: invalid server finished hash")
+	}
+
+	hs.transcript.Write(finished.marshal())
+
+	// Derive secrets that take context through the server Finished.
+
+	hs.trafficSecret = hs.suite.deriveSecret(hs.masterSecret,
+		clientApplicationTrafficLabel, hs.transcript)
+	serverSecret := hs.suite.deriveSecret(hs.masterSecret,
+		serverApplicationTrafficLabel, hs.transcript)
+	c.in.setTrafficSecret(hs.suite, serverSecret)
+
+	err = c.config.writeKeyLog(keyLogLabelClientTraffic, hs.hello.random, hs.trafficSecret)
+	if err != nil {
+		c.sendAlert(alertInternalError)
+		return err
+	}
+	err = c.config.writeKeyLog(keyLogLabelServerTraffic, hs.hello.random, serverSecret)
+	if err != nil {
+		c.sendAlert(alertInternalError)
+		return err
+	}
+
+	c.ekm = hs.suite.exportKeyingMaterial(hs.masterSecret, hs.transcript)
+
+	return nil
+}
+
+func (hs *clientHandshakeStateTLS13) sendClientCertificate() error {
+	c := hs.c
+
+	if hs.certReq == nil {
+		return nil
+	}
+
+	cert, err := c.getClientCertificate(&CertificateRequestInfo{
+		AcceptableCAs:    hs.certReq.certificateAuthorities,
+		SignatureSchemes: hs.certReq.supportedSignatureAlgorithms,
+		Version:          c.vers,
+		ctx:              hs.ctx,
+	})
+	if err != nil {
+		return err
+	}
+
+	certMsg := new(certificateMsgTLS13)
+
+	certMsg.certificate = *cert
+	certMsg.scts = hs.certReq.scts && len(cert.SignedCertificateTimestamps) > 0
+	certMsg.ocspStapling = hs.certReq.ocspStapling && len(cert.OCSPStaple) > 0
+
+	hs.transcript.Write(certMsg.marshal())
+	if _, err := c.writeRecord(recordTypeHandshake, certMsg.marshal()); err != nil {
+		return err
+	}
+
+	// If we sent an empty certificate message, skip the CertificateVerify.
+	if len(cert.Certificate) == 0 {
+		return nil
+	}
+
+	certVerifyMsg := new(certificateVerifyMsg)
+	certVerifyMsg.hasSignatureAlgorithm = true
+
+	certVerifyMsg.signatureAlgorithm, err = selectSignatureScheme(c.vers, cert, hs.certReq.supportedSignatureAlgorithms)
+	if err != nil {
+		// getClientCertificate returned a certificate incompatible with the
+		// CertificateRequestInfo supported signature algorithms.
+		c.sendAlert(alertHandshakeFailure)
+		return err
+	}
+
+	sigType, sigHash, err := typeAndHashFromSignatureScheme(certVerifyMsg.signatureAlgorithm)
+	if err != nil {
+		return c.sendAlert(alertInternalError)
+	}
+
+	signed := signedMessage(sigHash, clientSignatureContext, hs.transcript)
+	signOpts := crypto.SignerOpts(sigHash)
+	if sigType == signatureRSAPSS {
+		signOpts = &rsa.PSSOptions{SaltLength: rsa.PSSSaltLengthEqualsHash, Hash: sigHash}
+	}
+	sig, err := cert.PrivateKey.(crypto.Signer).Sign(c.config.rand(), signed, signOpts)
+	if err != nil {
+		c.sendAlert(alertInternalError)
+		return errors.New("tls: failed to sign handshake: " + err.Error())
+	}
+	certVerifyMsg.signature = sig
+
+	hs.transcript.Write(certVerifyMsg.marshal())
+	if _, err := c.writeRecord(recordTypeHandshake, certVerifyMsg.marshal()); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (hs *clientHandshakeStateTLS13) sendClientFinished() error {
+	c := hs.c
+
+	finished := &finishedMsg{
+		verifyData: hs.suite.finishedHash(c.out.trafficSecret, hs.transcript),
+	}
+
+	hs.transcript.Write(finished.marshal())
+	if _, err := c.writeRecord(recordTypeHandshake, finished.marshal()); err != nil {
+		return err
+	}
+
+	c.out.setTrafficSecret(hs.suite, hs.trafficSecret)
+
+	if !c.config.SessionTicketsDisabled && c.config.ClientSessionCache != nil {
+		c.resumptionSecret = hs.suite.deriveSecret(hs.masterSecret,
+			resumptionLabel, hs.transcript)
+	}
+
+	return nil
+}
+
+func (c *Conn) handleNewSessionTicket(msg *newSessionTicketMsgTLS13) error {
+	if !c.isClient {
+		c.sendAlert(alertUnexpectedMessage)
+		return errors.New("tls: received new session ticket from a client")
+	}
+
+	if c.config.SessionTicketsDisabled || c.config.ClientSessionCache == nil {
+		return nil
+	}
+
+	// See RFC 8446, Section 4.6.1.
+	if msg.lifetime == 0 {
+		return nil
+	}
+	lifetime := time.Duration(msg.lifetime) * time.Second
+	if lifetime > maxSessionTicketLifetime {
+		c.sendAlert(alertIllegalParameter)
+		return errors.New("tls: received a session ticket with invalid lifetime")
+	}
+
+	cipherSuite := cipherSuiteTLS13ByID(c.cipherSuite)
+	if cipherSuite == nil || c.resumptionSecret == nil {
+		return c.sendAlert(alertInternalError)
+	}
+
+	// Save the resumption_master_secret and nonce instead of deriving the PSK
+	// to do the least amount of work on NewSessionTicket messages before we
+	// know if the ticket will be used. Forward secrecy of resumed connections
+	// is guaranteed by the requirement for pskModeDHE.
+	session := &ClientSessionState{
+		sessionTicket:      msg.label,
+		vers:               c.vers,
+		cipherSuite:        c.cipherSuite,
+		masterSecret:       c.resumptionSecret,
+		serverCertificates: c.peerCertificates,
+		verifiedChains:     c.verifiedChains,
+		receivedAt:         c.config.time(),
+		nonce:              msg.nonce,
+		useBy:              c.config.time().Add(lifetime),
+		ageAdd:             msg.ageAdd,
+		ocspResponse:       c.ocspResponse,
+		scts:               c.scts,
+	}
+
+	cacheKey := clientSessionCacheKey(c.conn.RemoteAddr(), c.config)
+	c.config.ClientSessionCache.Put(cacheKey, session)
+
+	return nil
+}
diff --git a/contrib/go/_std_1.19/src/crypto/tls/handshake_messages.go b/contrib/go/_std_1.19/src/crypto/tls/handshake_messages.go
new file mode 100644
index 0000000000..7ab0f100b8
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/tls/handshake_messages.go
@@ -0,0 +1,1820 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package tls
+
+import (
+	"fmt"
+	"strings"
+
+	"golang.org/x/crypto/cryptobyte"
+)
+
+// The marshalingFunction type is an adapter to allow the use of ordinary
+// functions as cryptobyte.MarshalingValue.
+type marshalingFunction func(b *cryptobyte.Builder) error
+
+func (f marshalingFunction) Marshal(b *cryptobyte.Builder) error {
+	return f(b)
+}
+
+// addBytesWithLength appends a sequence of bytes to the cryptobyte.Builder. If
+// the length of the sequence is not the value specified, it produces an error.
+func addBytesWithLength(b *cryptobyte.Builder, v []byte, n int) {
+	b.AddValue(marshalingFunction(func(b *cryptobyte.Builder) error {
+		if len(v) != n {
+			return fmt.Errorf("invalid value length: expected %d, got %d", n, len(v))
+		}
+		b.AddBytes(v)
+		return nil
+	}))
+}
+
+// addUint64 appends a big-endian, 64-bit value to the cryptobyte.Builder.
+func addUint64(b *cryptobyte.Builder, v uint64) {
+	b.AddUint32(uint32(v >> 32))
+	b.AddUint32(uint32(v))
+}
+
+// readUint64 decodes a big-endian, 64-bit value into out and advances over it.
+// It reports whether the read was successful.
+func readUint64(s *cryptobyte.String, out *uint64) bool {
+	var hi, lo uint32
+	if !s.ReadUint32(&hi) || !s.ReadUint32(&lo) {
+		return false
+	}
+	*out = uint64(hi)<<32 | uint64(lo)
+	return true
+}
+
+// readUint8LengthPrefixed acts like s.ReadUint8LengthPrefixed, but targets a
+// []byte instead of a cryptobyte.String.
+func readUint8LengthPrefixed(s *cryptobyte.String, out *[]byte) bool {
+	return s.ReadUint8LengthPrefixed((*cryptobyte.String)(out))
+}
+
+// readUint16LengthPrefixed acts like s.ReadUint16LengthPrefixed, but targets a
+// []byte instead of a cryptobyte.String.
+func readUint16LengthPrefixed(s *cryptobyte.String, out *[]byte) bool {
+	return s.ReadUint16LengthPrefixed((*cryptobyte.String)(out))
+}
+
+// readUint24LengthPrefixed acts like s.ReadUint24LengthPrefixed, but targets a
+// []byte instead of a cryptobyte.String.
+func readUint24LengthPrefixed(s *cryptobyte.String, out *[]byte) bool {
+	return s.ReadUint24LengthPrefixed((*cryptobyte.String)(out))
+}
+
+type clientHelloMsg struct {
+	raw                              []byte
+	vers                             uint16
+	random                           []byte
+	sessionId                        []byte
+	cipherSuites                     []uint16
+	compressionMethods               []uint8
+	serverName                       string
+	ocspStapling                     bool
+	supportedCurves                  []CurveID
+	supportedPoints                  []uint8
+	ticketSupported                  bool
+	sessionTicket                    []uint8
+	supportedSignatureAlgorithms     []SignatureScheme
+	supportedSignatureAlgorithmsCert []SignatureScheme
+	secureRenegotiationSupported     bool
+	secureRenegotiation              []byte
+	alpnProtocols                    []string
+	scts                             bool
+	supportedVersions                []uint16
+	cookie                           []byte
+	keyShares                        []keyShare
+	earlyData                        bool
+	pskModes                         []uint8
+	pskIdentities                    []pskIdentity
+	pskBinders                       [][]byte
+}
+
+func (m *clientHelloMsg) marshal() []byte {
+	if m.raw != nil {
+		return m.raw
+	}
+
+	var b cryptobyte.Builder
+	b.AddUint8(typeClientHello)
+	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+		b.AddUint16(m.vers)
+		addBytesWithLength(b, m.random, 32)
+		b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
+			b.AddBytes(m.sessionId)
+		})
+		b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+			for _, suite := range m.cipherSuites {
+				b.AddUint16(suite)
+			}
+		})
+		b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
+			b.AddBytes(m.compressionMethods)
+		})
+
+		// If extensions aren't present, omit them.
+		var extensionsPresent bool
+		bWithoutExtensions := *b
+
+		b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+			if len(m.serverName) > 0 {
+				// RFC 6066, Section 3
+				b.AddUint16(extensionServerName)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+						b.AddUint8(0) // name_type = host_name
+						b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+							b.AddBytes([]byte(m.serverName))
+						})
+					})
+				})
+			}
+			if m.ocspStapling {
+				// RFC 4366, Section 3.6
+				b.AddUint16(extensionStatusRequest)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint8(1)  // status_type = ocsp
+					b.AddUint16(0) // empty responder_id_list
+					b.AddUint16(0) // empty request_extensions
+				})
+			}
+			if len(m.supportedCurves) > 0 {
+				// RFC 4492, sections 5.1.1 and RFC 8446, Section 4.2.7
+				b.AddUint16(extensionSupportedCurves)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+						for _, curve := range m.supportedCurves {
+							b.AddUint16(uint16(curve))
+						}
+					})
+				})
+			}
+			if len(m.supportedPoints) > 0 {
+				// RFC 4492, Section 5.1.2
+				b.AddUint16(extensionSupportedPoints)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
+						b.AddBytes(m.supportedPoints)
+					})
+				})
+			}
+			if m.ticketSupported {
+				// RFC 5077, Section 3.2
+				b.AddUint16(extensionSessionTicket)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddBytes(m.sessionTicket)
+				})
+			}
+			if len(m.supportedSignatureAlgorithms) > 0 {
+				// RFC 5246, Section 7.4.1.4.1
+				b.AddUint16(extensionSignatureAlgorithms)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+						for _, sigAlgo := range m.supportedSignatureAlgorithms {
+							b.AddUint16(uint16(sigAlgo))
+						}
+					})
+				})
+			}
+			if len(m.supportedSignatureAlgorithmsCert) > 0 {
+				// RFC 8446, Section 4.2.3
+				b.AddUint16(extensionSignatureAlgorithmsCert)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+						for _, sigAlgo := range m.supportedSignatureAlgorithmsCert {
+							b.AddUint16(uint16(sigAlgo))
+						}
+					})
+				})
+			}
+			if m.secureRenegotiationSupported {
+				// RFC 5746, Section 3.2
+				b.AddUint16(extensionRenegotiationInfo)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
+						b.AddBytes(m.secureRenegotiation)
+					})
+				})
+			}
+			if len(m.alpnProtocols) > 0 {
+				// RFC 7301, Section 3.1
+				b.AddUint16(extensionALPN)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+						for _, proto := range m.alpnProtocols {
+							b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
+								b.AddBytes([]byte(proto))
+							})
+						}
+					})
+				})
+			}
+			if m.scts {
+				// RFC 6962, Section 3.3.1
+				b.AddUint16(extensionSCT)
+				b.AddUint16(0) // empty extension_data
+			}
+			if len(m.supportedVersions) > 0 {
+				// RFC 8446, Section 4.2.1
+				b.AddUint16(extensionSupportedVersions)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
+						for _, vers := range m.supportedVersions {
+							b.AddUint16(vers)
+						}
+					})
+				})
+			}
+			if len(m.cookie) > 0 {
+				// RFC 8446, Section 4.2.2
+				b.AddUint16(extensionCookie)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+						b.AddBytes(m.cookie)
+					})
+				})
+			}
+			if len(m.keyShares) > 0 {
+				// RFC 8446, Section 4.2.8
+				b.AddUint16(extensionKeyShare)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+						for _, ks := range m.keyShares {
+							b.AddUint16(uint16(ks.group))
+							b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+								b.AddBytes(ks.data)
+							})
+						}
+					})
+				})
+			}
+			if m.earlyData {
+				// RFC 8446, Section 4.2.10
+				b.AddUint16(extensionEarlyData)
+				b.AddUint16(0) // empty extension_data
+			}
+			if len(m.pskModes) > 0 {
+				// RFC 8446, Section 4.2.9
+				b.AddUint16(extensionPSKModes)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
+						b.AddBytes(m.pskModes)
+					})
+				})
+			}
+			if len(m.pskIdentities) > 0 { // pre_shared_key must be the last extension
+				// RFC 8446, Section 4.2.11
+				b.AddUint16(extensionPreSharedKey)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+						for _, psk := range m.pskIdentities {
+							b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+								b.AddBytes(psk.label)
+							})
+							b.AddUint32(psk.obfuscatedTicketAge)
+						}
+					})
+					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+						for _, binder := range m.pskBinders {
+							b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
+								b.AddBytes(binder)
+							})
+						}
+					})
+				})
+			}
+
+			extensionsPresent = len(b.BytesOrPanic()) > 2
+		})
+
+		if !extensionsPresent {
+			*b = bWithoutExtensions
+		}
+	})
+
+	m.raw = b.BytesOrPanic()
+	return m.raw
+}
+
+// marshalWithoutBinders returns the ClientHello through the
+// PreSharedKeyExtension.identities field, according to RFC 8446, Section
+// 4.2.11.2. Note that m.pskBinders must be set to slices of the correct length.
+func (m *clientHelloMsg) marshalWithoutBinders() []byte {
+	bindersLen := 2 // uint16 length prefix
+	for _, binder := range m.pskBinders {
+		bindersLen += 1 // uint8 length prefix
+		bindersLen += len(binder)
+	}
+
+	fullMessage := m.marshal()
+	return fullMessage[:len(fullMessage)-bindersLen]
+}
+
+// updateBinders updates the m.pskBinders field, if necessary updating the
+// cached marshaled representation. The supplied binders must have the same
+// length as the current m.pskBinders.
+func (m *clientHelloMsg) updateBinders(pskBinders [][]byte) {
+	if len(pskBinders) != len(m.pskBinders) {
+		panic("tls: internal error: pskBinders length mismatch")
+	}
+	for i := range m.pskBinders {
+		if len(pskBinders[i]) != len(m.pskBinders[i]) {
+			panic("tls: internal error: pskBinders length mismatch")
+		}
+	}
+	m.pskBinders = pskBinders
+	if m.raw != nil {
+		lenWithoutBinders := len(m.marshalWithoutBinders())
+		b := cryptobyte.NewFixedBuilder(m.raw[:lenWithoutBinders])
+		b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+			for _, binder := range m.pskBinders {
+				b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddBytes(binder)
+				})
+			}
+		})
+		if out, err := b.Bytes(); err != nil || len(out) != len(m.raw) {
+			panic("tls: internal error: failed to update binders")
+		}
+	}
+}
+
+func (m *clientHelloMsg) unmarshal(data []byte) bool {
+	*m = clientHelloMsg{raw: data}
+	s := cryptobyte.String(data)
+
+	if !s.Skip(4) || // message type and uint24 length field
+		!s.ReadUint16(&m.vers) || !s.ReadBytes(&m.random, 32) ||
+		!readUint8LengthPrefixed(&s, &m.sessionId) {
+		return false
+	}
+
+	var cipherSuites cryptobyte.String
+	if !s.ReadUint16LengthPrefixed(&cipherSuites) {
+		return false
+	}
+	m.cipherSuites = []uint16{}
+	m.secureRenegotiationSupported = false
+	for !cipherSuites.Empty() {
+		var suite uint16
+		if !cipherSuites.ReadUint16(&suite) {
+			return false
+		}
+		if suite == scsvRenegotiation {
+			m.secureRenegotiationSupported = true
+		}
+		m.cipherSuites = append(m.cipherSuites, suite)
+	}
+
+	if !readUint8LengthPrefixed(&s, &m.compressionMethods) {
+		return false
+	}
+
+	if s.Empty() {
+		// ClientHello is optionally followed by extension data
+		return true
+	}
+
+	var extensions cryptobyte.String
+	if !s.ReadUint16LengthPrefixed(&extensions) || !s.Empty() {
+		return false
+	}
+
+	seenExts := make(map[uint16]bool)
+	for !extensions.Empty() {
+		var extension uint16
+		var extData cryptobyte.String
+		if !extensions.ReadUint16(&extension) ||
+			!extensions.ReadUint16LengthPrefixed(&extData) {
+			return false
+		}
+
+		if seenExts[extension] {
+			return false
+		}
+		seenExts[extension] = true
+
+		switch extension {
+		case extensionServerName:
+			// RFC 6066, Section 3
+			var nameList cryptobyte.String
+			if !extData.ReadUint16LengthPrefixed(&nameList) || nameList.Empty() {
+				return false
+			}
+			for !nameList.Empty() {
+				var nameType uint8
+				var serverName cryptobyte.String
+				if !nameList.ReadUint8(&nameType) ||
+					!nameList.ReadUint16LengthPrefixed(&serverName) ||
+					serverName.Empty() {
+					return false
+				}
+				if nameType != 0 {
+					continue
+				}
+				if len(m.serverName) != 0 {
+					// Multiple names of the same name_type are prohibited.
+					return false
+				}
+				m.serverName = string(serverName)
+				// An SNI value may not include a trailing dot.
+				if strings.HasSuffix(m.serverName, ".") {
+					return false
+				}
+			}
+		case extensionStatusRequest:
+			// RFC 4366, Section 3.6
+			var statusType uint8
+			var ignored cryptobyte.String
+			if !extData.ReadUint8(&statusType) ||
+				!extData.ReadUint16LengthPrefixed(&ignored) ||
+				!extData.ReadUint16LengthPrefixed(&ignored) {
+				return false
+			}
+			m.ocspStapling = statusType == statusTypeOCSP
+		case extensionSupportedCurves:
+			// RFC 4492, sections 5.1.1 and RFC 8446, Section 4.2.7
+			var curves cryptobyte.String
+			if !extData.ReadUint16LengthPrefixed(&curves) || curves.Empty() {
+				return false
+			}
+			for !curves.Empty() {
+				var curve uint16
+				if !curves.ReadUint16(&curve) {
+					return false
+				}
+				m.supportedCurves = append(m.supportedCurves, CurveID(curve))
+			}
+		case extensionSupportedPoints:
+			// RFC 4492, Section 5.1.2
+			if !readUint8LengthPrefixed(&extData, &m.supportedPoints) ||
+				len(m.supportedPoints) == 0 {
+				return false
+			}
+		case extensionSessionTicket:
+			// RFC 5077, Section 3.2
+			m.ticketSupported = true
+			extData.ReadBytes(&m.sessionTicket, len(extData))
+		case extensionSignatureAlgorithms:
+			// RFC 5246, Section 7.4.1.4.1
+			var sigAndAlgs cryptobyte.String
+			if !extData.ReadUint16LengthPrefixed(&sigAndAlgs) || sigAndAlgs.Empty() {
+				return false
+			}
+			for !sigAndAlgs.Empty() {
+				var sigAndAlg uint16
+				if !sigAndAlgs.ReadUint16(&sigAndAlg) {
+					return false
+				}
+				m.supportedSignatureAlgorithms = append(
+					m.supportedSignatureAlgorithms, SignatureScheme(sigAndAlg))
+			}
+		case extensionSignatureAlgorithmsCert:
+			// RFC 8446, Section 4.2.3
+			var sigAndAlgs cryptobyte.String
+			if !extData.ReadUint16LengthPrefixed(&sigAndAlgs) || sigAndAlgs.Empty() {
+				return false
+			}
+			for !sigAndAlgs.Empty() {
+				var sigAndAlg uint16
+				if !sigAndAlgs.ReadUint16(&sigAndAlg) {
+					return false
+				}
+				m.supportedSignatureAlgorithmsCert = append(
+					m.supportedSignatureAlgorithmsCert, SignatureScheme(sigAndAlg))
+			}
+		case extensionRenegotiationInfo:
+			// RFC 5746, Section 3.2
+			if !readUint8LengthPrefixed(&extData, &m.secureRenegotiation) {
+				return false
+			}
+			m.secureRenegotiationSupported = true
+		case extensionALPN:
+			// RFC 7301, Section 3.1
+			var protoList cryptobyte.String
+			if !extData.ReadUint16LengthPrefixed(&protoList) || protoList.Empty() {
+				return false
+			}
+			for !protoList.Empty() {
+				var proto cryptobyte.String
+				if !protoList.ReadUint8LengthPrefixed(&proto) || proto.Empty() {
+					return false
+				}
+				m.alpnProtocols = append(m.alpnProtocols, string(proto))
+			}
+		case extensionSCT:
+			// RFC 6962, Section 3.3.1
+			m.scts = true
+		case extensionSupportedVersions:
+			// RFC 8446, Section 4.2.1
+			var versList cryptobyte.String
+			if !extData.ReadUint8LengthPrefixed(&versList) || versList.Empty() {
+				return false
+			}
+			for !versList.Empty() {
+				var vers uint16
+				if !versList.ReadUint16(&vers) {
+					return false
+				}
+				m.supportedVersions = append(m.supportedVersions, vers)
+			}
+		case extensionCookie:
+			// RFC 8446, Section 4.2.2
+			if !readUint16LengthPrefixed(&extData, &m.cookie) ||
+				len(m.cookie) == 0 {
+				return false
+			}
+		case extensionKeyShare:
+			// RFC 8446, Section 4.2.8
+			var clientShares cryptobyte.String
+			if !extData.ReadUint16LengthPrefixed(&clientShares) {
+				return false
+			}
+			for !clientShares.Empty() {
+				var ks keyShare
+				if !clientShares.ReadUint16((*uint16)(&ks.group)) ||
+					!readUint16LengthPrefixed(&clientShares, &ks.data) ||
+					len(ks.data) == 0 {
+					return false
+				}
+				m.keyShares = append(m.keyShares, ks)
+			}
+		case extensionEarlyData:
+			// RFC 8446, Section 4.2.10
+			m.earlyData = true
+		case extensionPSKModes:
+			// RFC 8446, Section 4.2.9
+			if !readUint8LengthPrefixed(&extData, &m.pskModes) {
+				return false
+			}
+		case extensionPreSharedKey:
+			// RFC 8446, Section 4.2.11
+			if !extensions.Empty() {
+				return false // pre_shared_key must be the last extension
+			}
+			var identities cryptobyte.String
+			if !extData.ReadUint16LengthPrefixed(&identities) || identities.Empty() {
+				return false
+			}
+			for !identities.Empty() {
+				var psk pskIdentity
+				if !readUint16LengthPrefixed(&identities, &psk.label) ||
+					!identities.ReadUint32(&psk.obfuscatedTicketAge) ||
+					len(psk.label) == 0 {
+					return false
+				}
+				m.pskIdentities = append(m.pskIdentities, psk)
+			}
+			var binders cryptobyte.String
+			if !extData.ReadUint16LengthPrefixed(&binders) || binders.Empty() {
+				return false
+			}
+			for !binders.Empty() {
+				var binder []byte
+				if !readUint8LengthPrefixed(&binders, &binder) ||
+					len(binder) == 0 {
+					return false
+				}
+				m.pskBinders = append(m.pskBinders, binder)
+			}
+		default:
+			// Ignore unknown extensions.
+			continue
+		}
+
+		if !extData.Empty() {
+			return false
+		}
+	}
+
+	return true
+}
+
+type serverHelloMsg struct {
+	raw                          []byte
+	vers                         uint16
+	random                       []byte
+	sessionId                    []byte
+	cipherSuite                  uint16
+	compressionMethod            uint8
+	ocspStapling                 bool
+	ticketSupported              bool
+	secureRenegotiationSupported bool
+	secureRenegotiation          []byte
+	alpnProtocol                 string
+	scts                         [][]byte
+	supportedVersion             uint16
+	serverShare                  keyShare
+	selectedIdentityPresent      bool
+	selectedIdentity             uint16
+	supportedPoints              []uint8
+
+	// HelloRetryRequest extensions
+	cookie        []byte
+	selectedGroup CurveID
+}
+
+func (m *serverHelloMsg) marshal() []byte {
+	if m.raw != nil {
+		return m.raw
+	}
+
+	var b cryptobyte.Builder
+	b.AddUint8(typeServerHello)
+	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+		b.AddUint16(m.vers)
+		addBytesWithLength(b, m.random, 32)
+		b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
+			b.AddBytes(m.sessionId)
+		})
+		b.AddUint16(m.cipherSuite)
+		b.AddUint8(m.compressionMethod)
+
+		// If extensions aren't present, omit them.
+		var extensionsPresent bool
+		bWithoutExtensions := *b
+
+		b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+			if m.ocspStapling {
+				b.AddUint16(extensionStatusRequest)
+				b.AddUint16(0) // empty extension_data
+			}
+			if m.ticketSupported {
+				b.AddUint16(extensionSessionTicket)
+				b.AddUint16(0) // empty extension_data
+			}
+			if m.secureRenegotiationSupported {
+				b.AddUint16(extensionRenegotiationInfo)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
+						b.AddBytes(m.secureRenegotiation)
+					})
+				})
+			}
+			if len(m.alpnProtocol) > 0 {
+				b.AddUint16(extensionALPN)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+						b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
+							b.AddBytes([]byte(m.alpnProtocol))
+						})
+					})
+				})
+			}
+			if len(m.scts) > 0 {
+				b.AddUint16(extensionSCT)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+						for _, sct := range m.scts {
+							b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+								b.AddBytes(sct)
+							})
+						}
+					})
+				})
+			}
+			if m.supportedVersion != 0 {
+				b.AddUint16(extensionSupportedVersions)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint16(m.supportedVersion)
+				})
+			}
+			if m.serverShare.group != 0 {
+				b.AddUint16(extensionKeyShare)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint16(uint16(m.serverShare.group))
+					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+						b.AddBytes(m.serverShare.data)
+					})
+				})
+			}
+			if m.selectedIdentityPresent {
+				b.AddUint16(extensionPreSharedKey)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint16(m.selectedIdentity)
+				})
+			}
+
+			if len(m.cookie) > 0 {
+				b.AddUint16(extensionCookie)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+						b.AddBytes(m.cookie)
+					})
+				})
+			}
+			if m.selectedGroup != 0 {
+				b.AddUint16(extensionKeyShare)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint16(uint16(m.selectedGroup))
+				})
+			}
+			if len(m.supportedPoints) > 0 {
+				b.AddUint16(extensionSupportedPoints)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
+						b.AddBytes(m.supportedPoints)
+					})
+				})
+			}
+
+			extensionsPresent = len(b.BytesOrPanic()) > 2
+		})
+
+		if !extensionsPresent {
+			*b = bWithoutExtensions
+		}
+	})
+
+	m.raw = b.BytesOrPanic()
+	return m.raw
+}
+
+func (m *serverHelloMsg) unmarshal(data []byte) bool {
+	*m = serverHelloMsg{raw: data}
+	s := cryptobyte.String(data)
+
+	if !s.Skip(4) || // message type and uint24 length field
+		!s.ReadUint16(&m.vers) || !s.ReadBytes(&m.random, 32) ||
+		!readUint8LengthPrefixed(&s, &m.sessionId) ||
+		!s.ReadUint16(&m.cipherSuite) ||
+		!s.ReadUint8(&m.compressionMethod) {
+		return false
+	}
+
+	if s.Empty() {
+		// ServerHello is optionally followed by extension data
+		return true
+	}
+
+	var extensions cryptobyte.String
+	if !s.ReadUint16LengthPrefixed(&extensions) || !s.Empty() {
+		return false
+	}
+
+	seenExts := make(map[uint16]bool)
+	for !extensions.Empty() {
+		var extension uint16
+		var extData cryptobyte.String
+		if !extensions.ReadUint16(&extension) ||
+			!extensions.ReadUint16LengthPrefixed(&extData) {
+			return false
+		}
+
+		if seenExts[extension] {
+			return false
+		}
+		seenExts[extension] = true
+
+		switch extension {
+		case extensionStatusRequest:
+			m.ocspStapling = true
+		case extensionSessionTicket:
+			m.ticketSupported = true
+		case extensionRenegotiationInfo:
+			if !readUint8LengthPrefixed(&extData, &m.secureRenegotiation) {
+				return false
+			}
+			m.secureRenegotiationSupported = true
+		case extensionALPN:
+			var protoList cryptobyte.String
+			if !extData.ReadUint16LengthPrefixed(&protoList) || protoList.Empty() {
+				return false
+			}
+			var proto cryptobyte.String
+			if !protoList.ReadUint8LengthPrefixed(&proto) ||
+				proto.Empty() || !protoList.Empty() {
+				return false
+			}
+			m.alpnProtocol = string(proto)
+		case extensionSCT:
+			var sctList cryptobyte.String
+			if !extData.ReadUint16LengthPrefixed(&sctList) || sctList.Empty() {
+				return false
+			}
+			for !sctList.Empty() {
+				var sct []byte
+				if !readUint16LengthPrefixed(&sctList, &sct) ||
+					len(sct) == 0 {
+					return false
+				}
+				m.scts = append(m.scts, sct)
+			}
+		case extensionSupportedVersions:
+			if !extData.ReadUint16(&m.supportedVersion) {
+				return false
+			}
+		case extensionCookie:
+			if !readUint16LengthPrefixed(&extData, &m.cookie) ||
+				len(m.cookie) == 0 {
+				return false
+			}
+		case extensionKeyShare:
+			// This extension has different formats in SH and HRR, accept either
+			// and let the handshake logic decide. See RFC 8446, Section 4.2.8.
+			if len(extData) == 2 {
+				if !extData.ReadUint16((*uint16)(&m.selectedGroup)) {
+					return false
+				}
+			} else {
+				if !extData.ReadUint16((*uint16)(&m.serverShare.group)) ||
+					!readUint16LengthPrefixed(&extData, &m.serverShare.data) {
+					return false
+				}
+			}
+		case extensionPreSharedKey:
+			m.selectedIdentityPresent = true
+			if !extData.ReadUint16(&m.selectedIdentity) {
+				return false
+			}
+		case extensionSupportedPoints:
+			// RFC 4492, Section 5.1.2
+			if !readUint8LengthPrefixed(&extData, &m.supportedPoints) ||
+				len(m.supportedPoints) == 0 {
+				return false
+			}
+		default:
+			// Ignore unknown extensions.
+			continue
+		}
+
+		if !extData.Empty() {
+			return false
+		}
+	}
+
+	return true
+}
+
+type encryptedExtensionsMsg struct {
+	raw          []byte
+	alpnProtocol string
+}
+
+func (m *encryptedExtensionsMsg) marshal() []byte {
+	if m.raw != nil {
+		return m.raw
+	}
+
+	var b cryptobyte.Builder
+	b.AddUint8(typeEncryptedExtensions)
+	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+		b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+			if len(m.alpnProtocol) > 0 {
+				b.AddUint16(extensionALPN)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+						b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
+							b.AddBytes([]byte(m.alpnProtocol))
+						})
+					})
+				})
+			}
+		})
+	})
+
+	m.raw = b.BytesOrPanic()
+	return m.raw
+}
+
+func (m *encryptedExtensionsMsg) unmarshal(data []byte) bool {
+	*m = encryptedExtensionsMsg{raw: data}
+	s := cryptobyte.String(data)
+
+	var extensions cryptobyte.String
+	if !s.Skip(4) || // message type and uint24 length field
+		!s.ReadUint16LengthPrefixed(&extensions) || !s.Empty() {
+		return false
+	}
+
+	for !extensions.Empty() {
+		var extension uint16
+		var extData cryptobyte.String
+		if !extensions.ReadUint16(&extension) ||
+			!extensions.ReadUint16LengthPrefixed(&extData) {
+			return false
+		}
+
+		switch extension {
+		case extensionALPN:
+			var protoList cryptobyte.String
+			if !extData.ReadUint16LengthPrefixed(&protoList) || protoList.Empty() {
+				return false
+			}
+			var proto cryptobyte.String
+			if !protoList.ReadUint8LengthPrefixed(&proto) ||
+				proto.Empty() || !protoList.Empty() {
+				return false
+			}
+			m.alpnProtocol = string(proto)
+		default:
+			// Ignore unknown extensions.
+			continue
+		}
+
+		if !extData.Empty() {
+			return false
+		}
+	}
+
+	return true
+}
+
+type endOfEarlyDataMsg struct{}
+
+func (m *endOfEarlyDataMsg) marshal() []byte {
+	x := make([]byte, 4)
+	x[0] = typeEndOfEarlyData
+	return x
+}
+
+func (m *endOfEarlyDataMsg) unmarshal(data []byte) bool {
+	return len(data) == 4
+}
+
+type keyUpdateMsg struct {
+	raw             []byte
+	updateRequested bool
+}
+
+func (m *keyUpdateMsg) marshal() []byte {
+	if m.raw != nil {
+		return m.raw
+	}
+
+	var b cryptobyte.Builder
+	b.AddUint8(typeKeyUpdate)
+	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+		if m.updateRequested {
+			b.AddUint8(1)
+		} else {
+			b.AddUint8(0)
+		}
+	})
+
+	m.raw = b.BytesOrPanic()
+	return m.raw
+}
+
+func (m *keyUpdateMsg) unmarshal(data []byte) bool {
+	m.raw = data
+	s := cryptobyte.String(data)
+
+	var updateRequested uint8
+	if !s.Skip(4) || // message type and uint24 length field
+		!s.ReadUint8(&updateRequested) || !s.Empty() {
+		return false
+	}
+	switch updateRequested {
+	case 0:
+		m.updateRequested = false
+	case 1:
+		m.updateRequested = true
+	default:
+		return false
+	}
+	return true
+}
+
+type newSessionTicketMsgTLS13 struct {
+	raw          []byte
+	lifetime     uint32
+	ageAdd       uint32
+	nonce        []byte
+	label        []byte
+	maxEarlyData uint32
+}
+
+func (m *newSessionTicketMsgTLS13) marshal() []byte {
+	if m.raw != nil {
+		return m.raw
+	}
+
+	var b cryptobyte.Builder
+	b.AddUint8(typeNewSessionTicket)
+	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+		b.AddUint32(m.lifetime)
+		b.AddUint32(m.ageAdd)
+		b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
+			b.AddBytes(m.nonce)
+		})
+		b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+			b.AddBytes(m.label)
+		})
+
+		b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+			if m.maxEarlyData > 0 {
+				b.AddUint16(extensionEarlyData)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint32(m.maxEarlyData)
+				})
+			}
+		})
+	})
+
+	m.raw = b.BytesOrPanic()
+	return m.raw
+}
+
+func (m *newSessionTicketMsgTLS13) unmarshal(data []byte) bool {
+	*m = newSessionTicketMsgTLS13{raw: data}
+	s := cryptobyte.String(data)
+
+	var extensions cryptobyte.String
+	if !s.Skip(4) || // message type and uint24 length field
+		!s.ReadUint32(&m.lifetime) ||
+		!s.ReadUint32(&m.ageAdd) ||
+		!readUint8LengthPrefixed(&s, &m.nonce) ||
+		!readUint16LengthPrefixed(&s, &m.label) ||
+		!s.ReadUint16LengthPrefixed(&extensions) ||
+		!s.Empty() {
+		return false
+	}
+
+	for !extensions.Empty() {
+		var extension uint16
+		var extData cryptobyte.String
+		if !extensions.ReadUint16(&extension) ||
+			!extensions.ReadUint16LengthPrefixed(&extData) {
+			return false
+		}
+
+		switch extension {
+		case extensionEarlyData:
+			if !extData.ReadUint32(&m.maxEarlyData) {
+				return false
+			}
+		default:
+			// Ignore unknown extensions.
+			continue
+		}
+
+		if !extData.Empty() {
+			return false
+		}
+	}
+
+	return true
+}
+
+type certificateRequestMsgTLS13 struct {
+	raw                              []byte
+	ocspStapling                     bool
+	scts                             bool
+	supportedSignatureAlgorithms     []SignatureScheme
+	supportedSignatureAlgorithmsCert []SignatureScheme
+	certificateAuthorities           [][]byte
+}
+
+func (m *certificateRequestMsgTLS13) marshal() []byte {
+	if m.raw != nil {
+		return m.raw
+	}
+
+	var b cryptobyte.Builder
+	b.AddUint8(typeCertificateRequest)
+	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+		// certificate_request_context (SHALL be zero length unless used for
+		// post-handshake authentication)
+		b.AddUint8(0)
+
+		b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+			if m.ocspStapling {
+				b.AddUint16(extensionStatusRequest)
+				b.AddUint16(0) // empty extension_data
+			}
+			if m.scts {
+				// RFC 8446, Section 4.4.2.1 makes no mention of
+				// signed_certificate_timestamp in CertificateRequest, but
+				// "Extensions in the Certificate message from the client MUST
+				// correspond to extensions in the CertificateRequest message
+				// from the server." and it appears in the table in Section 4.2.
+				b.AddUint16(extensionSCT)
+				b.AddUint16(0) // empty extension_data
+			}
+			if len(m.supportedSignatureAlgorithms) > 0 {
+				b.AddUint16(extensionSignatureAlgorithms)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+						for _, sigAlgo := range m.supportedSignatureAlgorithms {
+							b.AddUint16(uint16(sigAlgo))
+						}
+					})
+				})
+			}
+			if len(m.supportedSignatureAlgorithmsCert) > 0 {
+				b.AddUint16(extensionSignatureAlgorithmsCert)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+						for _, sigAlgo := range m.supportedSignatureAlgorithmsCert {
+							b.AddUint16(uint16(sigAlgo))
+						}
+					})
+				})
+			}
+			if len(m.certificateAuthorities) > 0 {
+				b.AddUint16(extensionCertificateAuthorities)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+						for _, ca := range m.certificateAuthorities {
+							b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+								b.AddBytes(ca)
+							})
+						}
+					})
+				})
+			}
+		})
+	})
+
+	m.raw = b.BytesOrPanic()
+	return m.raw
+}
+
+func (m *certificateRequestMsgTLS13) unmarshal(data []byte) bool {
+	*m = certificateRequestMsgTLS13{raw: data}
+	s := cryptobyte.String(data)
+
+	var context, extensions cryptobyte.String
+	if !s.Skip(4) || // message type and uint24 length field
+		!s.ReadUint8LengthPrefixed(&context) || !context.Empty() ||
+		!s.ReadUint16LengthPrefixed(&extensions) ||
+		!s.Empty() {
+		return false
+	}
+
+	for !extensions.Empty() {
+		var extension uint16
+		var extData cryptobyte.String
+		if !extensions.ReadUint16(&extension) ||
+			!extensions.ReadUint16LengthPrefixed(&extData) {
+			return false
+		}
+
+		switch extension {
+		case extensionStatusRequest:
+			m.ocspStapling = true
+		case extensionSCT:
+			m.scts = true
+		case extensionSignatureAlgorithms:
+			var sigAndAlgs cryptobyte.String
+			if !extData.ReadUint16LengthPrefixed(&sigAndAlgs) || sigAndAlgs.Empty() {
+				return false
+			}
+			for !sigAndAlgs.Empty() {
+				var sigAndAlg uint16
+				if !sigAndAlgs.ReadUint16(&sigAndAlg) {
+					return false
+				}
+				m.supportedSignatureAlgorithms = append(
+					m.supportedSignatureAlgorithms, SignatureScheme(sigAndAlg))
+			}
+		case extensionSignatureAlgorithmsCert:
+			var sigAndAlgs cryptobyte.String
+			if !extData.ReadUint16LengthPrefixed(&sigAndAlgs) || sigAndAlgs.Empty() {
+				return false
+			}
+			for !sigAndAlgs.Empty() {
+				var sigAndAlg uint16
+				if !sigAndAlgs.ReadUint16(&sigAndAlg) {
+					return false
+				}
+				m.supportedSignatureAlgorithmsCert = append(
+					m.supportedSignatureAlgorithmsCert, SignatureScheme(sigAndAlg))
+			}
+		case extensionCertificateAuthorities:
+			var auths cryptobyte.String
+			if !extData.ReadUint16LengthPrefixed(&auths) || auths.Empty() {
+				return false
+			}
+			for !auths.Empty() {
+				var ca []byte
+				if !readUint16LengthPrefixed(&auths, &ca) || len(ca) == 0 {
+					return false
+				}
+				m.certificateAuthorities = append(m.certificateAuthorities, ca)
+			}
+		default:
+			// Ignore unknown extensions.
+			continue
+		}
+
+		if !extData.Empty() {
+			return false
+		}
+	}
+
+	return true
+}
+
+type certificateMsg struct {
+	raw          []byte
+	certificates [][]byte
+}
+
+func (m *certificateMsg) marshal() (x []byte) {
+	if m.raw != nil {
+		return m.raw
+	}
+
+	var i int
+	for _, slice := range m.certificates {
+		i += len(slice)
+	}
+
+	length := 3 + 3*len(m.certificates) + i
+	x = make([]byte, 4+length)
+	x[0] = typeCertificate
+	x[1] = uint8(length >> 16)
+	x[2] = uint8(length >> 8)
+	x[3] = uint8(length)
+
+	certificateOctets := length - 3
+	x[4] = uint8(certificateOctets >> 16)
+	x[5] = uint8(certificateOctets >> 8)
+	x[6] = uint8(certificateOctets)
+
+	y := x[7:]
+	for _, slice := range m.certificates {
+		y[0] = uint8(len(slice) >> 16)
+		y[1] = uint8(len(slice) >> 8)
+		y[2] = uint8(len(slice))
+		copy(y[3:], slice)
+		y = y[3+len(slice):]
+	}
+
+	m.raw = x
+	return
+}
+
+func (m *certificateMsg) unmarshal(data []byte) bool {
+	if len(data) < 7 {
+		return false
+	}
+
+	m.raw = data
+	certsLen := uint32(data[4])<<16 | uint32(data[5])<<8 | uint32(data[6])
+	if uint32(len(data)) != certsLen+7 {
+		return false
+	}
+
+	numCerts := 0
+	d := data[7:]
+	for certsLen > 0 {
+		if len(d) < 4 {
+			return false
+		}
+		certLen := uint32(d[0])<<16 | uint32(d[1])<<8 | uint32(d[2])
+		if uint32(len(d)) < 3+certLen {
+			return false
+		}
+		d = d[3+certLen:]
+		certsLen -= 3 + certLen
+		numCerts++
+	}
+
+	m.certificates = make([][]byte, numCerts)
+	d = data[7:]
+	for i := 0; i < numCerts; i++ {
+		certLen := uint32(d[0])<<16 | uint32(d[1])<<8 | uint32(d[2])
+		m.certificates[i] = d[3 : 3+certLen]
+		d = d[3+certLen:]
+	}
+
+	return true
+}
+
+type certificateMsgTLS13 struct {
+	raw          []byte
+	certificate  Certificate
+	ocspStapling bool
+	scts         bool
+}
+
+func (m *certificateMsgTLS13) marshal() []byte {
+	if m.raw != nil {
+		return m.raw
+	}
+
+	var b cryptobyte.Builder
+	b.AddUint8(typeCertificate)
+	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+		b.AddUint8(0) // certificate_request_context
+
+		certificate := m.certificate
+		if !m.ocspStapling {
+			certificate.OCSPStaple = nil
+		}
+		if !m.scts {
+			certificate.SignedCertificateTimestamps = nil
+		}
+		marshalCertificate(b, certificate)
+	})
+
+	m.raw = b.BytesOrPanic()
+	return m.raw
+}
+
+func marshalCertificate(b *cryptobyte.Builder, certificate Certificate) {
+	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+		for i, cert := range certificate.Certificate {
+			b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+				b.AddBytes(cert)
+			})
+			b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+				if i > 0 {
+					// This library only supports OCSP and SCT for leaf certificates.
+					return
+				}
+				if certificate.OCSPStaple != nil {
+					b.AddUint16(extensionStatusRequest)
+					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+						b.AddUint8(statusTypeOCSP)
+						b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+							b.AddBytes(certificate.OCSPStaple)
+						})
+					})
+				}
+				if certificate.SignedCertificateTimestamps != nil {
+					b.AddUint16(extensionSCT)
+					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+						b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+							for _, sct := range certificate.SignedCertificateTimestamps {
+								b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+									b.AddBytes(sct)
+								})
+							}
+						})
+					})
+				}
+			})
+		}
+	})
+}
+
+func (m *certificateMsgTLS13) unmarshal(data []byte) bool {
+	*m = certificateMsgTLS13{raw: data}
+	s := cryptobyte.String(data)
+
+	var context cryptobyte.String
+	if !s.Skip(4) || // message type and uint24 length field
+		!s.ReadUint8LengthPrefixed(&context) || !context.Empty() ||
+		!unmarshalCertificate(&s, &m.certificate) ||
+		!s.Empty() {
+		return false
+	}
+
+	m.scts = m.certificate.SignedCertificateTimestamps != nil
+	m.ocspStapling = m.certificate.OCSPStaple != nil
+
+	return true
+}
+
+func unmarshalCertificate(s *cryptobyte.String, certificate *Certificate) bool {
+	var certList cryptobyte.String
+	if !s.ReadUint24LengthPrefixed(&certList) {
+		return false
+	}
+	for !certList.Empty() {
+		var cert []byte
+		var extensions cryptobyte.String
+		if !readUint24LengthPrefixed(&certList, &cert) ||
+			!certList.ReadUint16LengthPrefixed(&extensions) {
+			return false
+		}
+		certificate.Certificate = append(certificate.Certificate, cert)
+		for !extensions.Empty() {
+			var extension uint16
+			var extData cryptobyte.String
+			if !extensions.ReadUint16(&extension) ||
+				!extensions.ReadUint16LengthPrefixed(&extData) {
+				return false
+			}
+			if len(certificate.Certificate) > 1 {
+				// This library only supports OCSP and SCT for leaf certificates.
+				continue
+			}
+
+			switch extension {
+			case extensionStatusRequest:
+				var statusType uint8
+				if !extData.ReadUint8(&statusType) || statusType != statusTypeOCSP ||
+					!readUint24LengthPrefixed(&extData, &certificate.OCSPStaple) ||
+					len(certificate.OCSPStaple) == 0 {
+					return false
+				}
+			case extensionSCT:
+				var sctList cryptobyte.String
+				if !extData.ReadUint16LengthPrefixed(&sctList) || sctList.Empty() {
+					return false
+				}
+				for !sctList.Empty() {
+					var sct []byte
+					if !readUint16LengthPrefixed(&sctList, &sct) ||
+						len(sct) == 0 {
+						return false
+					}
+					certificate.SignedCertificateTimestamps = append(
+						certificate.SignedCertificateTimestamps, sct)
+				}
+			default:
+				// Ignore unknown extensions.
+				continue
+			}
+
+			if !extData.Empty() {
+				return false
+			}
+		}
+	}
+	return true
+}
+
+type serverKeyExchangeMsg struct {
+	raw []byte
+	key []byte
+}
+
+func (m *serverKeyExchangeMsg) marshal() []byte {
+	if m.raw != nil {
+		return m.raw
+	}
+	length := len(m.key)
+	x := make([]byte, length+4)
+	x[0] = typeServerKeyExchange
+	x[1] = uint8(length >> 16)
+	x[2] = uint8(length >> 8)
+	x[3] = uint8(length)
+	copy(x[4:], m.key)
+
+	m.raw = x
+	return x
+}
+
+func (m *serverKeyExchangeMsg) unmarshal(data []byte) bool {
+	m.raw = data
+	if len(data) < 4 {
+		return false
+	}
+	m.key = data[4:]
+	return true
+}
+
+type certificateStatusMsg struct {
+	raw      []byte
+	response []byte
+}
+
+func (m *certificateStatusMsg) marshal() []byte {
+	if m.raw != nil {
+		return m.raw
+	}
+
+	var b cryptobyte.Builder
+	b.AddUint8(typeCertificateStatus)
+	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+		b.AddUint8(statusTypeOCSP)
+		b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+			b.AddBytes(m.response)
+		})
+	})
+
+	m.raw = b.BytesOrPanic()
+	return m.raw
+}
+
+func (m *certificateStatusMsg) unmarshal(data []byte) bool {
+	m.raw = data
+	s := cryptobyte.String(data)
+
+	var statusType uint8
+	if !s.Skip(4) || // message type and uint24 length field
+		!s.ReadUint8(&statusType) || statusType != statusTypeOCSP ||
+		!readUint24LengthPrefixed(&s, &m.response) ||
+		len(m.response) == 0 || !s.Empty() {
+		return false
+	}
+	return true
+}
+
+type serverHelloDoneMsg struct{}
+
+func (m *serverHelloDoneMsg) marshal() []byte {
+	x := make([]byte, 4)
+	x[0] = typeServerHelloDone
+	return x
+}
+
+func (m *serverHelloDoneMsg) unmarshal(data []byte) bool {
+	return len(data) == 4
+}
+
+type clientKeyExchangeMsg struct {
+	raw        []byte
+	ciphertext []byte
+}
+
+func (m *clientKeyExchangeMsg) marshal() []byte {
+	if m.raw != nil {
+		return m.raw
+	}
+	length := len(m.ciphertext)
+	x := make([]byte, length+4)
+	x[0] = typeClientKeyExchange
+	x[1] = uint8(length >> 16)
+	x[2] = uint8(length >> 8)
+	x[3] = uint8(length)
+	copy(x[4:], m.ciphertext)
+
+	m.raw = x
+	return x
+}
+
+func (m *clientKeyExchangeMsg) unmarshal(data []byte) bool {
+	m.raw = data
+	if len(data) < 4 {
+		return false
+	}
+	l := int(data[1])<<16 | int(data[2])<<8 | int(data[3])
+	if l != len(data)-4 {
+		return false
+	}
+	m.ciphertext = data[4:]
+	return true
+}
+
+type finishedMsg struct {
+	raw        []byte
+	verifyData []byte
+}
+
+func (m *finishedMsg) marshal() []byte {
+	if m.raw != nil {
+		return m.raw
+	}
+
+	var b cryptobyte.Builder
+	b.AddUint8(typeFinished)
+	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+		b.AddBytes(m.verifyData)
+	})
+
+	m.raw = b.BytesOrPanic()
+	return m.raw
+}
+
+func (m *finishedMsg) unmarshal(data []byte) bool {
+	m.raw = data
+	s := cryptobyte.String(data)
+	return s.Skip(1) &&
+		readUint24LengthPrefixed(&s, &m.verifyData) &&
+		s.Empty()
+}
+
+type certificateRequestMsg struct {
+	raw []byte
+	// hasSignatureAlgorithm indicates whether this message includes a list of
+	// supported signature algorithms. This change was introduced with TLS 1.2.
+	hasSignatureAlgorithm bool
+
+	certificateTypes             []byte
+	supportedSignatureAlgorithms []SignatureScheme
+	certificateAuthorities       [][]byte
+}
+
+func (m *certificateRequestMsg) marshal() (x []byte) {
+	if m.raw != nil {
+		return m.raw
+	}
+
+	// See RFC 4346, Section 7.4.4.
+	length := 1 + len(m.certificateTypes) + 2
+	casLength := 0
+	for _, ca := range m.certificateAuthorities {
+		casLength += 2 + len(ca)
+	}
+	length += casLength
+
+	if m.hasSignatureAlgorithm {
+		length += 2 + 2*len(m.supportedSignatureAlgorithms)
+	}
+
+	x = make([]byte, 4+length)
+	x[0] = typeCertificateRequest
+	x[1] = uint8(length >> 16)
+	x[2] = uint8(length >> 8)
+	x[3] = uint8(length)
+
+	x[4] = uint8(len(m.certificateTypes))
+
+	copy(x[5:], m.certificateTypes)
+	y := x[5+len(m.certificateTypes):]
+
+	if m.hasSignatureAlgorithm {
+		n := len(m.supportedSignatureAlgorithms) * 2
+		y[0] = uint8(n >> 8)
+		y[1] = uint8(n)
+		y = y[2:]
+		for _, sigAlgo := range m.supportedSignatureAlgorithms {
+			y[0] = uint8(sigAlgo >> 8)
+			y[1] = uint8(sigAlgo)
+			y = y[2:]
+		}
+	}
+
+	y[0] = uint8(casLength >> 8)
+	y[1] = uint8(casLength)
+	y = y[2:]
+	for _, ca := range m.certificateAuthorities {
+		y[0] = uint8(len(ca) >> 8)
+		y[1] = uint8(len(ca))
+		y = y[2:]
+		copy(y, ca)
+		y = y[len(ca):]
+	}
+
+	m.raw = x
+	return
+}
+
+func (m *certificateRequestMsg) unmarshal(data []byte) bool {
+	m.raw = data
+
+	if len(data) < 5 {
+		return false
+	}
+
+	length := uint32(data[1])<<16 | uint32(data[2])<<8 | uint32(data[3])
+	if uint32(len(data))-4 != length {
+		return false
+	}
+
+	numCertTypes := int(data[4])
+	data = data[5:]
+	if numCertTypes == 0 || len(data) <= numCertTypes {
+		return false
+	}
+
+	m.certificateTypes = make([]byte, numCertTypes)
+	if copy(m.certificateTypes, data) != numCertTypes {
+		return false
+	}
+
+	data = data[numCertTypes:]
+
+	if m.hasSignatureAlgorithm {
+		if len(data) < 2 {
+			return false
+		}
+		sigAndHashLen := uint16(data[0])<<8 | uint16(data[1])
+		data = data[2:]
+		if sigAndHashLen&1 != 0 {
+			return false
+		}
+		if len(data) < int(sigAndHashLen) {
+			return false
+		}
+		numSigAlgos := sigAndHashLen / 2
+		m.supportedSignatureAlgorithms = make([]SignatureScheme, numSigAlgos)
+		for i := range m.supportedSignatureAlgorithms {
+			m.supportedSignatureAlgorithms[i] = SignatureScheme(data[0])<<8 | SignatureScheme(data[1])
+			data = data[2:]
+		}
+	}
+
+	if len(data) < 2 {
+		return false
+	}
+	casLength := uint16(data[0])<<8 | uint16(data[1])
+	data = data[2:]
+	if len(data) < int(casLength) {
+		return false
+	}
+	cas := make([]byte, casLength)
+	copy(cas, data)
+	data = data[casLength:]
+
+	m.certificateAuthorities = nil
+	for len(cas) > 0 {
+		if len(cas) < 2 {
+			return false
+		}
+		caLen := uint16(cas[0])<<8 | uint16(cas[1])
+		cas = cas[2:]
+
+		if len(cas) < int(caLen) {
+			return false
+		}
+
+		m.certificateAuthorities = append(m.certificateAuthorities, cas[:caLen])
+		cas = cas[caLen:]
+	}
+
+	return len(data) == 0
+}
+
+type certificateVerifyMsg struct {
+	raw                   []byte
+	hasSignatureAlgorithm bool // format change introduced in TLS 1.2
+	signatureAlgorithm    SignatureScheme
+	signature             []byte
+}
+
+func (m *certificateVerifyMsg) marshal() (x []byte) {
+	if m.raw != nil {
+		return m.raw
+	}
+
+	var b cryptobyte.Builder
+	b.AddUint8(typeCertificateVerify)
+	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+		if m.hasSignatureAlgorithm {
+			b.AddUint16(uint16(m.signatureAlgorithm))
+		}
+		b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+			b.AddBytes(m.signature)
+		})
+	})
+
+	m.raw = b.BytesOrPanic()
+	return m.raw
+}
+
+func (m *certificateVerifyMsg) unmarshal(data []byte) bool {
+	m.raw = data
+	s := cryptobyte.String(data)
+
+	if !s.Skip(4) { // message type and uint24 length field
+		return false
+	}
+	if m.hasSignatureAlgorithm {
+		if !s.ReadUint16((*uint16)(&m.signatureAlgorithm)) {
+			return false
+		}
+	}
+	return readUint16LengthPrefixed(&s, &m.signature) && s.Empty()
+}
+
+type newSessionTicketMsg struct {
+	raw    []byte
+	ticket []byte
+}
+
+func (m *newSessionTicketMsg) marshal() (x []byte) {
+	if m.raw != nil {
+		return m.raw
+	}
+
+	// See RFC 5077, Section 3.3.
+	ticketLen := len(m.ticket)
+	length := 2 + 4 + ticketLen
+	x = make([]byte, 4+length)
+	x[0] = typeNewSessionTicket
+	x[1] = uint8(length >> 16)
+	x[2] = uint8(length >> 8)
+	x[3] = uint8(length)
+	x[8] = uint8(ticketLen >> 8)
+	x[9] = uint8(ticketLen)
+	copy(x[10:], m.ticket)
+
+	m.raw = x
+
+	return
+}
+
+func (m *newSessionTicketMsg) unmarshal(data []byte) bool {
+	m.raw = data
+
+	if len(data) < 10 {
+		return false
+	}
+
+	length := uint32(data[1])<<16 | uint32(data[2])<<8 | uint32(data[3])
+	if uint32(len(data))-4 != length {
+		return false
+	}
+
+	ticketLen := int(data[8])<<8 + int(data[9])
+	if len(data)-10 != ticketLen {
+		return false
+	}
+
+	m.ticket = data[10:]
+
+	return true
+}
+
+type helloRequestMsg struct {
+}
+
+func (*helloRequestMsg) marshal() []byte {
+	return []byte{typeHelloRequest, 0, 0, 0}
+}
+
+func (*helloRequestMsg) unmarshal(data []byte) bool {
+	return len(data) == 4
+}
diff --git a/contrib/go/_std_1.19/src/crypto/tls/handshake_server.go b/contrib/go/_std_1.19/src/crypto/tls/handshake_server.go
new file mode 100644
index 0000000000..92b38cb11b
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/tls/handshake_server.go
@@ -0,0 +1,882 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package tls
+
+import (
+	"context"
+	"crypto"
+	"crypto/ecdsa"
+	"crypto/ed25519"
+	"crypto/rsa"
+	"crypto/subtle"
+	"crypto/x509"
+	"errors"
+	"fmt"
+	"hash"
+	"io"
+	"sync/atomic"
+	"time"
+)
+
+// serverHandshakeState contains details of a server handshake in progress.
+// It's discarded once the handshake has completed.
+type serverHandshakeState struct {
+	c            *Conn
+	ctx          context.Context
+	clientHello  *clientHelloMsg
+	hello        *serverHelloMsg
+	suite        *cipherSuite
+	ecdheOk      bool
+	ecSignOk     bool
+	rsaDecryptOk bool
+	rsaSignOk    bool
+	sessionState *sessionState
+	finishedHash finishedHash
+	masterSecret []byte
+	cert         *Certificate
+}
+
+// serverHandshake performs a TLS handshake as a server.
+func (c *Conn) serverHandshake(ctx context.Context) error {
+	clientHello, err := c.readClientHello(ctx)
+	if err != nil {
+		return err
+	}
+
+	if c.vers == VersionTLS13 {
+		hs := serverHandshakeStateTLS13{
+			c:           c,
+			ctx:         ctx,
+			clientHello: clientHello,
+		}
+		return hs.handshake()
+	}
+
+	hs := serverHandshakeState{
+		c:           c,
+		ctx:         ctx,
+		clientHello: clientHello,
+	}
+	return hs.handshake()
+}
+
+func (hs *serverHandshakeState) handshake() error {
+	c := hs.c
+
+	if err := hs.processClientHello(); err != nil {
+		return err
+	}
+
+	// For an overview of TLS handshaking, see RFC 5246, Section 7.3.
+	c.buffering = true
+	if hs.checkForResumption() {
+		// The client has included a session ticket and so we do an abbreviated handshake.
+		c.didResume = true
+		if err := hs.doResumeHandshake(); err != nil {
+			return err
+		}
+		if err := hs.establishKeys(); err != nil {
+			return err
+		}
+		if err := hs.sendSessionTicket(); err != nil {
+			return err
+		}
+		if err := hs.sendFinished(c.serverFinished[:]); err != nil {
+			return err
+		}
+		if _, err := c.flush(); err != nil {
+			return err
+		}
+		c.clientFinishedIsFirst = false
+		if err := hs.readFinished(nil); err != nil {
+			return err
+		}
+	} else {
+		// The client didn't include a session ticket, or it wasn't
+		// valid so we do a full handshake.
+		if err := hs.pickCipherSuite(); err != nil {
+			return err
+		}
+		if err := hs.doFullHandshake(); err != nil {
+			return err
+		}
+		if err := hs.establishKeys(); err != nil {
+			return err
+		}
+		if err := hs.readFinished(c.clientFinished[:]); err != nil {
+			return err
+		}
+		c.clientFinishedIsFirst = true
+		c.buffering = true
+		if err := hs.sendSessionTicket(); err != nil {
+			return err
+		}
+		if err := hs.sendFinished(nil); err != nil {
+			return err
+		}
+		if _, err := c.flush(); err != nil {
+			return err
+		}
+	}
+
+	c.ekm = ekmFromMasterSecret(c.vers, hs.suite, hs.masterSecret, hs.clientHello.random, hs.hello.random)
+	atomic.StoreUint32(&c.handshakeStatus, 1)
+
+	return nil
+}
+
+// readClientHello reads a ClientHello message and selects the protocol version.
+func (c *Conn) readClientHello(ctx context.Context) (*clientHelloMsg, error) {
+	msg, err := c.readHandshake()
+	if err != nil {
+		return nil, err
+	}
+	clientHello, ok := msg.(*clientHelloMsg)
+	if !ok {
+		c.sendAlert(alertUnexpectedMessage)
+		return nil, unexpectedMessageError(clientHello, msg)
+	}
+
+	var configForClient *Config
+	originalConfig := c.config
+	if c.config.GetConfigForClient != nil {
+		chi := clientHelloInfo(ctx, c, clientHello)
+		if configForClient, err = c.config.GetConfigForClient(chi); err != nil {
+			c.sendAlert(alertInternalError)
+			return nil, err
+		} else if configForClient != nil {
+			c.config = configForClient
+		}
+	}
+	c.ticketKeys = originalConfig.ticketKeys(configForClient)
+
+	clientVersions := clientHello.supportedVersions
+	if len(clientHello.supportedVersions) == 0 {
+		clientVersions = supportedVersionsFromMax(clientHello.vers)
+	}
+	c.vers, ok = c.config.mutualVersion(roleServer, clientVersions)
+	if !ok {
+		c.sendAlert(alertProtocolVersion)
+		return nil, fmt.Errorf("tls: client offered only unsupported versions: %x", clientVersions)
+	}
+	c.haveVers = true
+	c.in.version = c.vers
+	c.out.version = c.vers
+
+	return clientHello, nil
+}
+
+func (hs *serverHandshakeState) processClientHello() error {
+	c := hs.c
+
+	hs.hello = new(serverHelloMsg)
+	hs.hello.vers = c.vers
+
+	foundCompression := false
+	// We only support null compression, so check that the client offered it.
+	for _, compression := range hs.clientHello.compressionMethods {
+		if compression == compressionNone {
+			foundCompression = true
+			break
+		}
+	}
+
+	if !foundCompression {
+		c.sendAlert(alertHandshakeFailure)
+		return errors.New("tls: client does not support uncompressed connections")
+	}
+
+	hs.hello.random = make([]byte, 32)
+	serverRandom := hs.hello.random
+	// Downgrade protection canaries. See RFC 8446, Section 4.1.3.
+	maxVers := c.config.maxSupportedVersion(roleServer)
+	if maxVers >= VersionTLS12 && c.vers < maxVers || testingOnlyForceDowngradeCanary {
+		if c.vers == VersionTLS12 {
+			copy(serverRandom[24:], downgradeCanaryTLS12)
+		} else {
+			copy(serverRandom[24:], downgradeCanaryTLS11)
+		}
+		serverRandom = serverRandom[:24]
+	}
+	_, err := io.ReadFull(c.config.rand(), serverRandom)
+	if err != nil {
+		c.sendAlert(alertInternalError)
+		return err
+	}
+
+	if len(hs.clientHello.secureRenegotiation) != 0 {
+		c.sendAlert(alertHandshakeFailure)
+		return errors.New("tls: initial handshake had non-empty renegotiation extension")
+	}
+
+	hs.hello.secureRenegotiationSupported = hs.clientHello.secureRenegotiationSupported
+	hs.hello.compressionMethod = compressionNone
+	if len(hs.clientHello.serverName) > 0 {
+		c.serverName = hs.clientHello.serverName
+	}
+
+	selectedProto, err := negotiateALPN(c.config.NextProtos, hs.clientHello.alpnProtocols)
+	if err != nil {
+		c.sendAlert(alertNoApplicationProtocol)
+		return err
+	}
+	hs.hello.alpnProtocol = selectedProto
+	c.clientProtocol = selectedProto
+
+	hs.cert, err = c.config.getCertificate(clientHelloInfo(hs.ctx, c, hs.clientHello))
+	if err != nil {
+		if err == errNoCertificates {
+			c.sendAlert(alertUnrecognizedName)
+		} else {
+			c.sendAlert(alertInternalError)
+		}
+		return err
+	}
+	if hs.clientHello.scts {
+		hs.hello.scts = hs.cert.SignedCertificateTimestamps
+	}
+
+	hs.ecdheOk = supportsECDHE(c.config, hs.clientHello.supportedCurves, hs.clientHello.supportedPoints)
+
+	if hs.ecdheOk && len(hs.clientHello.supportedPoints) > 0 {
+		// Although omitting the ec_point_formats extension is permitted, some
+		// old OpenSSL version will refuse to handshake if not present.
+		//
+		// Per RFC 4492, section 5.1.2, implementations MUST support the
+		// uncompressed point format. See golang.org/issue/31943.
+		hs.hello.supportedPoints = []uint8{pointFormatUncompressed}
+	}
+
+	if priv, ok := hs.cert.PrivateKey.(crypto.Signer); ok {
+		switch priv.Public().(type) {
+		case *ecdsa.PublicKey:
+			hs.ecSignOk = true
+		case ed25519.PublicKey:
+			hs.ecSignOk = true
+		case *rsa.PublicKey:
+			hs.rsaSignOk = true
+		default:
+			c.sendAlert(alertInternalError)
+			return fmt.Errorf("tls: unsupported signing key type (%T)", priv.Public())
+		}
+	}
+	if priv, ok := hs.cert.PrivateKey.(crypto.Decrypter); ok {
+		switch priv.Public().(type) {
+		case *rsa.PublicKey:
+			hs.rsaDecryptOk = true
+		default:
+			c.sendAlert(alertInternalError)
+			return fmt.Errorf("tls: unsupported decryption key type (%T)", priv.Public())
+		}
+	}
+
+	return nil
+}
+
+// negotiateALPN picks a shared ALPN protocol that both sides support in server
+// preference order. If ALPN is not configured or the peer doesn't support it,
+// it returns "" and no error.
+func negotiateALPN(serverProtos, clientProtos []string) (string, error) {
+	if len(serverProtos) == 0 || len(clientProtos) == 0 {
+		return "", nil
+	}
+	var http11fallback bool
+	for _, s := range serverProtos {
+		for _, c := range clientProtos {
+			if s == c {
+				return s, nil
+			}
+			if s == "h2" && c == "http/1.1" {
+				http11fallback = true
+			}
+		}
+	}
+	// As a special case, let http/1.1 clients connect to h2 servers as if they
+	// didn't support ALPN. We used not to enforce protocol overlap, so over
+	// time a number of HTTP servers were configured with only "h2", but
+	// expected to accept connections from "http/1.1" clients. See Issue 46310.
+	if http11fallback {
+		return "", nil
+	}
+	return "", fmt.Errorf("tls: client requested unsupported application protocols (%s)", clientProtos)
+}
+
+// supportsECDHE returns whether ECDHE key exchanges can be used with this
+// pre-TLS 1.3 client.
+func supportsECDHE(c *Config, supportedCurves []CurveID, supportedPoints []uint8) bool {
+	supportsCurve := false
+	for _, curve := range supportedCurves {
+		if c.supportsCurve(curve) {
+			supportsCurve = true
+			break
+		}
+	}
+
+	supportsPointFormat := false
+	for _, pointFormat := range supportedPoints {
+		if pointFormat == pointFormatUncompressed {
+			supportsPointFormat = true
+			break
+		}
+	}
+	// Per RFC 8422, Section 5.1.2, if the Supported Point Formats extension is
+	// missing, uncompressed points are supported. If supportedPoints is empty,
+	// the extension must be missing, as an empty extension body is rejected by
+	// the parser. See https://go.dev/issue/49126.
+	if len(supportedPoints) == 0 {
+		supportsPointFormat = true
+	}
+
+	return supportsCurve && supportsPointFormat
+}
+
+func (hs *serverHandshakeState) pickCipherSuite() error {
+	c := hs.c
+
+	preferenceOrder := cipherSuitesPreferenceOrder
+	if !hasAESGCMHardwareSupport || !aesgcmPreferred(hs.clientHello.cipherSuites) {
+		preferenceOrder = cipherSuitesPreferenceOrderNoAES
+	}
+
+	configCipherSuites := c.config.cipherSuites()
+	preferenceList := make([]uint16, 0, len(configCipherSuites))
+	for _, suiteID := range preferenceOrder {
+		for _, id := range configCipherSuites {
+			if id == suiteID {
+				preferenceList = append(preferenceList, id)
+				break
+			}
+		}
+	}
+
+	hs.suite = selectCipherSuite(preferenceList, hs.clientHello.cipherSuites, hs.cipherSuiteOk)
+	if hs.suite == nil {
+		c.sendAlert(alertHandshakeFailure)
+		return errors.New("tls: no cipher suite supported by both client and server")
+	}
+	c.cipherSuite = hs.suite.id
+
+	for _, id := range hs.clientHello.cipherSuites {
+		if id == TLS_FALLBACK_SCSV {
+			// The client is doing a fallback connection. See RFC 7507.
+			if hs.clientHello.vers < c.config.maxSupportedVersion(roleServer) {
+				c.sendAlert(alertInappropriateFallback)
+				return errors.New("tls: client using inappropriate protocol fallback")
+			}
+			break
+		}
+	}
+
+	return nil
+}
+
+func (hs *serverHandshakeState) cipherSuiteOk(c *cipherSuite) bool {
+	if c.flags&suiteECDHE != 0 {
+		if !hs.ecdheOk {
+			return false
+		}
+		if c.flags&suiteECSign != 0 {
+			if !hs.ecSignOk {
+				return false
+			}
+		} else if !hs.rsaSignOk {
+			return false
+		}
+	} else if !hs.rsaDecryptOk {
+		return false
+	}
+	if hs.c.vers < VersionTLS12 && c.flags&suiteTLS12 != 0 {
+		return false
+	}
+	return true
+}
+
+// checkForResumption reports whether we should perform resumption on this connection.
+func (hs *serverHandshakeState) checkForResumption() bool {
+	c := hs.c
+
+	if c.config.SessionTicketsDisabled {
+		return false
+	}
+
+	plaintext, usedOldKey := c.decryptTicket(hs.clientHello.sessionTicket)
+	if plaintext == nil {
+		return false
+	}
+	hs.sessionState = &sessionState{usedOldKey: usedOldKey}
+	ok := hs.sessionState.unmarshal(plaintext)
+	if !ok {
+		return false
+	}
+
+	createdAt := time.Unix(int64(hs.sessionState.createdAt), 0)
+	if c.config.time().Sub(createdAt) > maxSessionTicketLifetime {
+		return false
+	}
+
+	// Never resume a session for a different TLS version.
+	if c.vers != hs.sessionState.vers {
+		return false
+	}
+
+	cipherSuiteOk := false
+	// Check that the client is still offering the ciphersuite in the session.
+	for _, id := range hs.clientHello.cipherSuites {
+		if id == hs.sessionState.cipherSuite {
+			cipherSuiteOk = true
+			break
+		}
+	}
+	if !cipherSuiteOk {
+		return false
+	}
+
+	// Check that we also support the ciphersuite from the session.
+	hs.suite = selectCipherSuite([]uint16{hs.sessionState.cipherSuite},
+		c.config.cipherSuites(), hs.cipherSuiteOk)
+	if hs.suite == nil {
+		return false
+	}
+
+	sessionHasClientCerts := len(hs.sessionState.certificates) != 0
+	needClientCerts := requiresClientCert(c.config.ClientAuth)
+	if needClientCerts && !sessionHasClientCerts {
+		return false
+	}
+	if sessionHasClientCerts && c.config.ClientAuth == NoClientCert {
+		return false
+	}
+
+	return true
+}
+
+func (hs *serverHandshakeState) doResumeHandshake() error {
+	c := hs.c
+
+	hs.hello.cipherSuite = hs.suite.id
+	c.cipherSuite = hs.suite.id
+	// We echo the client's session ID in the ServerHello to let it know
+	// that we're doing a resumption.
+	hs.hello.sessionId = hs.clientHello.sessionId
+	hs.hello.ticketSupported = hs.sessionState.usedOldKey
+	hs.finishedHash = newFinishedHash(c.vers, hs.suite)
+	hs.finishedHash.discardHandshakeBuffer()
+	hs.finishedHash.Write(hs.clientHello.marshal())
+	hs.finishedHash.Write(hs.hello.marshal())
+	if _, err := c.writeRecord(recordTypeHandshake, hs.hello.marshal()); err != nil {
+		return err
+	}
+
+	if err := c.processCertsFromClient(Certificate{
+		Certificate: hs.sessionState.certificates,
+	}); err != nil {
+		return err
+	}
+
+	if c.config.VerifyConnection != nil {
+		if err := c.config.VerifyConnection(c.connectionStateLocked()); err != nil {
+			c.sendAlert(alertBadCertificate)
+			return err
+		}
+	}
+
+	hs.masterSecret = hs.sessionState.masterSecret
+
+	return nil
+}
+
+func (hs *serverHandshakeState) doFullHandshake() error {
+	c := hs.c
+
+	if hs.clientHello.ocspStapling && len(hs.cert.OCSPStaple) > 0 {
+		hs.hello.ocspStapling = true
+	}
+
+	hs.hello.ticketSupported = hs.clientHello.ticketSupported && !c.config.SessionTicketsDisabled
+	hs.hello.cipherSuite = hs.suite.id
+
+	hs.finishedHash = newFinishedHash(hs.c.vers, hs.suite)
+	if c.config.ClientAuth == NoClientCert {
+		// No need to keep a full record of the handshake if client
+		// certificates won't be used.
+		hs.finishedHash.discardHandshakeBuffer()
+	}
+	hs.finishedHash.Write(hs.clientHello.marshal())
+	hs.finishedHash.Write(hs.hello.marshal())
+	if _, err := c.writeRecord(recordTypeHandshake, hs.hello.marshal()); err != nil {
+		return err
+	}
+
+	certMsg := new(certificateMsg)
+	certMsg.certificates = hs.cert.Certificate
+	hs.finishedHash.Write(certMsg.marshal())
+	if _, err := c.writeRecord(recordTypeHandshake, certMsg.marshal()); err != nil {
+		return err
+	}
+
+	if hs.hello.ocspStapling {
+		certStatus := new(certificateStatusMsg)
+		certStatus.response = hs.cert.OCSPStaple
+		hs.finishedHash.Write(certStatus.marshal())
+		if _, err := c.writeRecord(recordTypeHandshake, certStatus.marshal()); err != nil {
+			return err
+		}
+	}
+
+	keyAgreement := hs.suite.ka(c.vers)
+	skx, err := keyAgreement.generateServerKeyExchange(c.config, hs.cert, hs.clientHello, hs.hello)
+	if err != nil {
+		c.sendAlert(alertHandshakeFailure)
+		return err
+	}
+	if skx != nil {
+		hs.finishedHash.Write(skx.marshal())
+		if _, err := c.writeRecord(recordTypeHandshake, skx.marshal()); err != nil {
+			return err
+		}
+	}
+
+	var certReq *certificateRequestMsg
+	if c.config.ClientAuth >= RequestClientCert {
+		// Request a client certificate
+		certReq = new(certificateRequestMsg)
+		certReq.certificateTypes = []byte{
+			byte(certTypeRSASign),
+			byte(certTypeECDSASign),
+		}
+		if c.vers >= VersionTLS12 {
+			certReq.hasSignatureAlgorithm = true
+			certReq.supportedSignatureAlgorithms = supportedSignatureAlgorithms()
+		}
+
+		// An empty list of certificateAuthorities signals to
+		// the client that it may send any certificate in response
+		// to our request. When we know the CAs we trust, then
+		// we can send them down, so that the client can choose
+		// an appropriate certificate to give to us.
+		if c.config.ClientCAs != nil {
+			certReq.certificateAuthorities = c.config.ClientCAs.Subjects()
+		}
+		hs.finishedHash.Write(certReq.marshal())
+		if _, err := c.writeRecord(recordTypeHandshake, certReq.marshal()); err != nil {
+			return err
+		}
+	}
+
+	helloDone := new(serverHelloDoneMsg)
+	hs.finishedHash.Write(helloDone.marshal())
+	if _, err := c.writeRecord(recordTypeHandshake, helloDone.marshal()); err != nil {
+		return err
+	}
+
+	if _, err := c.flush(); err != nil {
+		return err
+	}
+
+	var pub crypto.PublicKey // public key for client auth, if any
+
+	msg, err := c.readHandshake()
+	if err != nil {
+		return err
+	}
+
+	// If we requested a client certificate, then the client must send a
+	// certificate message, even if it's empty.
+	if c.config.ClientAuth >= RequestClientCert {
+		certMsg, ok := msg.(*certificateMsg)
+		if !ok {
+			c.sendAlert(alertUnexpectedMessage)
+			return unexpectedMessageError(certMsg, msg)
+		}
+		hs.finishedHash.Write(certMsg.marshal())
+
+		if err := c.processCertsFromClient(Certificate{
+			Certificate: certMsg.certificates,
+		}); err != nil {
+			return err
+		}
+		if len(certMsg.certificates) != 0 {
+			pub = c.peerCertificates[0].PublicKey
+		}
+
+		msg, err = c.readHandshake()
+		if err != nil {
+			return err
+		}
+	}
+	if c.config.VerifyConnection != nil {
+		if err := c.config.VerifyConnection(c.connectionStateLocked()); err != nil {
+			c.sendAlert(alertBadCertificate)
+			return err
+		}
+	}
+
+	// Get client key exchange
+	ckx, ok := msg.(*clientKeyExchangeMsg)
+	if !ok {
+		c.sendAlert(alertUnexpectedMessage)
+		return unexpectedMessageError(ckx, msg)
+	}
+	hs.finishedHash.Write(ckx.marshal())
+
+	preMasterSecret, err := keyAgreement.processClientKeyExchange(c.config, hs.cert, ckx, c.vers)
+	if err != nil {
+		c.sendAlert(alertHandshakeFailure)
+		return err
+	}
+	hs.masterSecret = masterFromPreMasterSecret(c.vers, hs.suite, preMasterSecret, hs.clientHello.random, hs.hello.random)
+	if err := c.config.writeKeyLog(keyLogLabelTLS12, hs.clientHello.random, hs.masterSecret); err != nil {
+		c.sendAlert(alertInternalError)
+		return err
+	}
+
+	// If we received a client cert in response to our certificate request message,
+	// the client will send us a certificateVerifyMsg immediately after the
+	// clientKeyExchangeMsg. This message is a digest of all preceding
+	// handshake-layer messages that is signed using the private key corresponding
+	// to the client's certificate. This allows us to verify that the client is in
+	// possession of the private key of the certificate.
+	if len(c.peerCertificates) > 0 {
+		msg, err = c.readHandshake()
+		if err != nil {
+			return err
+		}
+		certVerify, ok := msg.(*certificateVerifyMsg)
+		if !ok {
+			c.sendAlert(alertUnexpectedMessage)
+			return unexpectedMessageError(certVerify, msg)
+		}
+
+		var sigType uint8
+		var sigHash crypto.Hash
+		if c.vers >= VersionTLS12 {
+			if !isSupportedSignatureAlgorithm(certVerify.signatureAlgorithm, certReq.supportedSignatureAlgorithms) {
+				c.sendAlert(alertIllegalParameter)
+				return errors.New("tls: client certificate used with invalid signature algorithm")
+			}
+			sigType, sigHash, err = typeAndHashFromSignatureScheme(certVerify.signatureAlgorithm)
+			if err != nil {
+				return c.sendAlert(alertInternalError)
+			}
+		} else {
+			sigType, sigHash, err = legacyTypeAndHashFromPublicKey(pub)
+			if err != nil {
+				c.sendAlert(alertIllegalParameter)
+				return err
+			}
+		}
+
+		signed := hs.finishedHash.hashForClientCertificate(sigType, sigHash, hs.masterSecret)
+		if err := verifyHandshakeSignature(sigType, pub, sigHash, signed, certVerify.signature); err != nil {
+			c.sendAlert(alertDecryptError)
+			return errors.New("tls: invalid signature by the client certificate: " + err.Error())
+		}
+
+		hs.finishedHash.Write(certVerify.marshal())
+	}
+
+	hs.finishedHash.discardHandshakeBuffer()
+
+	return nil
+}
+
+func (hs *serverHandshakeState) establishKeys() error {
+	c := hs.c
+
+	clientMAC, serverMAC, clientKey, serverKey, clientIV, serverIV :=
+		keysFromMasterSecret(c.vers, hs.suite, hs.masterSecret, hs.clientHello.random, hs.hello.random, hs.suite.macLen, hs.suite.keyLen, hs.suite.ivLen)
+
+	var clientCipher, serverCipher any
+	var clientHash, serverHash hash.Hash
+
+	if hs.suite.aead == nil {
+		clientCipher = hs.suite.cipher(clientKey, clientIV, true /* for reading */)
+		clientHash = hs.suite.mac(clientMAC)
+		serverCipher = hs.suite.cipher(serverKey, serverIV, false /* not for reading */)
+		serverHash = hs.suite.mac(serverMAC)
+	} else {
+		clientCipher = hs.suite.aead(clientKey, clientIV)
+		serverCipher = hs.suite.aead(serverKey, serverIV)
+	}
+
+	c.in.prepareCipherSpec(c.vers, clientCipher, clientHash)
+	c.out.prepareCipherSpec(c.vers, serverCipher, serverHash)
+
+	return nil
+}
+
+func (hs *serverHandshakeState) readFinished(out []byte) error {
+	c := hs.c
+
+	if err := c.readChangeCipherSpec(); err != nil {
+		return err
+	}
+
+	msg, err := c.readHandshake()
+	if err != nil {
+		return err
+	}
+	clientFinished, ok := msg.(*finishedMsg)
+	if !ok {
+		c.sendAlert(alertUnexpectedMessage)
+		return unexpectedMessageError(clientFinished, msg)
+	}
+
+	verify := hs.finishedHash.clientSum(hs.masterSecret)
+	if len(verify) != len(clientFinished.verifyData) ||
+		subtle.ConstantTimeCompare(verify, clientFinished.verifyData) != 1 {
+		c.sendAlert(alertHandshakeFailure)
+		return errors.New("tls: client's Finished message is incorrect")
+	}
+
+	hs.finishedHash.Write(clientFinished.marshal())
+	copy(out, verify)
+	return nil
+}
+
+func (hs *serverHandshakeState) sendSessionTicket() error {
+	// ticketSupported is set in a resumption handshake if the
+	// ticket from the client was encrypted with an old session
+	// ticket key and thus a refreshed ticket should be sent.
+	if !hs.hello.ticketSupported {
+		return nil
+	}
+
+	c := hs.c
+	m := new(newSessionTicketMsg)
+
+	createdAt := uint64(c.config.time().Unix())
+	if hs.sessionState != nil {
+		// If this is re-wrapping an old key, then keep
+		// the original time it was created.
+		createdAt = hs.sessionState.createdAt
+	}
+
+	var certsFromClient [][]byte
+	for _, cert := range c.peerCertificates {
+		certsFromClient = append(certsFromClient, cert.Raw)
+	}
+	state := sessionState{
+		vers:         c.vers,
+		cipherSuite:  hs.suite.id,
+		createdAt:    createdAt,
+		masterSecret: hs.masterSecret,
+		certificates: certsFromClient,
+	}
+	var err error
+	m.ticket, err = c.encryptTicket(state.marshal())
+	if err != nil {
+		return err
+	}
+
+	hs.finishedHash.Write(m.marshal())
+	if _, err := c.writeRecord(recordTypeHandshake, m.marshal()); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (hs *serverHandshakeState) sendFinished(out []byte) error {
+	c := hs.c
+
+	if _, err := c.writeRecord(recordTypeChangeCipherSpec, []byte{1}); err != nil {
+		return err
+	}
+
+	finished := new(finishedMsg)
+	finished.verifyData = hs.finishedHash.serverSum(hs.masterSecret)
+	hs.finishedHash.Write(finished.marshal())
+	if _, err := c.writeRecord(recordTypeHandshake, finished.marshal()); err != nil {
+		return err
+	}
+
+	copy(out, finished.verifyData)
+
+	return nil
+}
+
+// processCertsFromClient takes a chain of client certificates either from a
+// Certificates message or from a sessionState and verifies them. It returns
+// the public key of the leaf certificate.
+func (c *Conn) processCertsFromClient(certificate Certificate) error {
+	certificates := certificate.Certificate
+	certs := make([]*x509.Certificate, len(certificates))
+	var err error
+	for i, asn1Data := range certificates {
+		if certs[i], err = x509.ParseCertificate(asn1Data); err != nil {
+			c.sendAlert(alertBadCertificate)
+			return errors.New("tls: failed to parse client certificate: " + err.Error())
+		}
+	}
+
+	if len(certs) == 0 && requiresClientCert(c.config.ClientAuth) {
+		c.sendAlert(alertBadCertificate)
+		return errors.New("tls: client didn't provide a certificate")
+	}
+
+	if c.config.ClientAuth >= VerifyClientCertIfGiven && len(certs) > 0 {
+		opts := x509.VerifyOptions{
+			Roots:         c.config.ClientCAs,
+			CurrentTime:   c.config.time(),
+			Intermediates: x509.NewCertPool(),
+			KeyUsages:     []x509.ExtKeyUsage{x509.ExtKeyUsageClientAuth},
+		}
+
+		for _, cert := range certs[1:] {
+			opts.Intermediates.AddCert(cert)
+		}
+
+		chains, err := certs[0].Verify(opts)
+		if err != nil {
+			c.sendAlert(alertBadCertificate)
+			return errors.New("tls: failed to verify client certificate: " + err.Error())
+		}
+
+		c.verifiedChains = chains
+	}
+
+	c.peerCertificates = certs
+	c.ocspResponse = certificate.OCSPStaple
+	c.scts = certificate.SignedCertificateTimestamps
+
+	if len(certs) > 0 {
+		switch certs[0].PublicKey.(type) {
+		case *ecdsa.PublicKey, *rsa.PublicKey, ed25519.PublicKey:
+		default:
+			c.sendAlert(alertUnsupportedCertificate)
+			return fmt.Errorf("tls: client certificate contains an unsupported public key of type %T", certs[0].PublicKey)
+		}
+	}
+
+	if c.config.VerifyPeerCertificate != nil {
+		if err := c.config.VerifyPeerCertificate(certificates, c.verifiedChains); err != nil {
+			c.sendAlert(alertBadCertificate)
+			return err
+		}
+	}
+
+	return nil
+}
+
+func clientHelloInfo(ctx context.Context, c *Conn, clientHello *clientHelloMsg) *ClientHelloInfo {
+	supportedVersions := clientHello.supportedVersions
+	if len(clientHello.supportedVersions) == 0 {
+		supportedVersions = supportedVersionsFromMax(clientHello.vers)
+	}
+
+	return &ClientHelloInfo{
+		CipherSuites:      clientHello.cipherSuites,
+		ServerName:        clientHello.serverName,
+		SupportedCurves:   clientHello.supportedCurves,
+		SupportedPoints:   clientHello.supportedPoints,
+		SignatureSchemes:  clientHello.supportedSignatureAlgorithms,
+		SupportedProtos:   clientHello.alpnProtocols,
+		SupportedVersions: supportedVersions,
+		Conn:              c.conn,
+		config:            c.config,
+		ctx:               ctx,
+	}
+}
diff --git a/contrib/go/_std_1.19/src/crypto/tls/handshake_server_tls13.go b/contrib/go/_std_1.19/src/crypto/tls/handshake_server_tls13.go
new file mode 100644
index 0000000000..03a477f7be
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/tls/handshake_server_tls13.go
@@ -0,0 +1,876 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package tls
+
+import (
+	"bytes"
+	"context"
+	"crypto"
+	"crypto/hmac"
+	"crypto/rsa"
+	"encoding/binary"
+	"errors"
+	"hash"
+	"io"
+	"sync/atomic"
+	"time"
+)
+
+// maxClientPSKIdentities is the number of client PSK identities the server will
+// attempt to validate. It will ignore the rest not to let cheap ClientHello
+// messages cause too much work in session ticket decryption attempts.
+const maxClientPSKIdentities = 5
+
+type serverHandshakeStateTLS13 struct {
+	c               *Conn
+	ctx             context.Context
+	clientHello     *clientHelloMsg
+	hello           *serverHelloMsg
+	sentDummyCCS    bool
+	usingPSK        bool
+	suite           *cipherSuiteTLS13
+	cert            *Certificate
+	sigAlg          SignatureScheme
+	earlySecret     []byte
+	sharedKey       []byte
+	handshakeSecret []byte
+	masterSecret    []byte
+	trafficSecret   []byte // client_application_traffic_secret_0
+	transcript      hash.Hash
+	clientFinished  []byte
+}
+
+func (hs *serverHandshakeStateTLS13) handshake() error {
+	c := hs.c
+
+	if needFIPS() {
+		return errors.New("tls: internal error: TLS 1.3 reached in FIPS mode")
+	}
+
+	// For an overview of the TLS 1.3 handshake, see RFC 8446, Section 2.
+	if err := hs.processClientHello(); err != nil {
+		return err
+	}
+	if err := hs.checkForResumption(); err != nil {
+		return err
+	}
+	if err := hs.pickCertificate(); err != nil {
+		return err
+	}
+	c.buffering = true
+	if err := hs.sendServerParameters(); err != nil {
+		return err
+	}
+	if err := hs.sendServerCertificate(); err != nil {
+		return err
+	}
+	if err := hs.sendServerFinished(); err != nil {
+		return err
+	}
+	// Note that at this point we could start sending application data without
+	// waiting for the client's second flight, but the application might not
+	// expect the lack of replay protection of the ClientHello parameters.
+	if _, err := c.flush(); err != nil {
+		return err
+	}
+	if err := hs.readClientCertificate(); err != nil {
+		return err
+	}
+	if err := hs.readClientFinished(); err != nil {
+		return err
+	}
+
+	atomic.StoreUint32(&c.handshakeStatus, 1)
+
+	return nil
+}
+
+func (hs *serverHandshakeStateTLS13) processClientHello() error {
+	c := hs.c
+
+	hs.hello = new(serverHelloMsg)
+
+	// TLS 1.3 froze the ServerHello.legacy_version field, and uses
+	// supported_versions instead. See RFC 8446, sections 4.1.3 and 4.2.1.
+	hs.hello.vers = VersionTLS12
+	hs.hello.supportedVersion = c.vers
+
+	if len(hs.clientHello.supportedVersions) == 0 {
+		c.sendAlert(alertIllegalParameter)
+		return errors.New("tls: client used the legacy version field to negotiate TLS 1.3")
+	}
+
+	// Abort if the client is doing a fallback and landing lower than what we
+	// support. See RFC 7507, which however does not specify the interaction
+	// with supported_versions. The only difference is that with
+	// supported_versions a client has a chance to attempt a [TLS 1.2, TLS 1.4]
+	// handshake in case TLS 1.3 is broken but 1.2 is not. Alas, in that case,
+	// it will have to drop the TLS_FALLBACK_SCSV protection if it falls back to
+	// TLS 1.2, because a TLS 1.3 server would abort here. The situation before
+	// supported_versions was not better because there was just no way to do a
+	// TLS 1.4 handshake without risking the server selecting TLS 1.3.
+	for _, id := range hs.clientHello.cipherSuites {
+		if id == TLS_FALLBACK_SCSV {
+			// Use c.vers instead of max(supported_versions) because an attacker
+			// could defeat this by adding an arbitrary high version otherwise.
+			if c.vers < c.config.maxSupportedVersion(roleServer) {
+				c.sendAlert(alertInappropriateFallback)
+				return errors.New("tls: client using inappropriate protocol fallback")
+			}
+			break
+		}
+	}
+
+	if len(hs.clientHello.compressionMethods) != 1 ||
+		hs.clientHello.compressionMethods[0] != compressionNone {
+		c.sendAlert(alertIllegalParameter)
+		return errors.New("tls: TLS 1.3 client supports illegal compression methods")
+	}
+
+	hs.hello.random = make([]byte, 32)
+	if _, err := io.ReadFull(c.config.rand(), hs.hello.random); err != nil {
+		c.sendAlert(alertInternalError)
+		return err
+	}
+
+	if len(hs.clientHello.secureRenegotiation) != 0 {
+		c.sendAlert(alertHandshakeFailure)
+		return errors.New("tls: initial handshake had non-empty renegotiation extension")
+	}
+
+	if hs.clientHello.earlyData {
+		// See RFC 8446, Section 4.2.10 for the complicated behavior required
+		// here. The scenario is that a different server at our address offered
+		// to accept early data in the past, which we can't handle. For now, all
+		// 0-RTT enabled session tickets need to expire before a Go server can
+		// replace a server or join a pool. That's the same requirement that
+		// applies to mixing or replacing with any TLS 1.2 server.
+		c.sendAlert(alertUnsupportedExtension)
+		return errors.New("tls: client sent unexpected early data")
+	}
+
+	hs.hello.sessionId = hs.clientHello.sessionId
+	hs.hello.compressionMethod = compressionNone
+
+	preferenceList := defaultCipherSuitesTLS13
+	if !hasAESGCMHardwareSupport || !aesgcmPreferred(hs.clientHello.cipherSuites) {
+		preferenceList = defaultCipherSuitesTLS13NoAES
+	}
+	for _, suiteID := range preferenceList {
+		hs.suite = mutualCipherSuiteTLS13(hs.clientHello.cipherSuites, suiteID)
+		if hs.suite != nil {
+			break
+		}
+	}
+	if hs.suite == nil {
+		c.sendAlert(alertHandshakeFailure)
+		return errors.New("tls: no cipher suite supported by both client and server")
+	}
+	c.cipherSuite = hs.suite.id
+	hs.hello.cipherSuite = hs.suite.id
+	hs.transcript = hs.suite.hash.New()
+
+	// Pick the ECDHE group in server preference order, but give priority to
+	// groups with a key share, to avoid a HelloRetryRequest round-trip.
+	var selectedGroup CurveID
+	var clientKeyShare *keyShare
+GroupSelection:
+	for _, preferredGroup := range c.config.curvePreferences() {
+		for _, ks := range hs.clientHello.keyShares {
+			if ks.group == preferredGroup {
+				selectedGroup = ks.group
+				clientKeyShare = &ks
+				break GroupSelection
+			}
+		}
+		if selectedGroup != 0 {
+			continue
+		}
+		for _, group := range hs.clientHello.supportedCurves {
+			if group == preferredGroup {
+				selectedGroup = group
+				break
+			}
+		}
+	}
+	if selectedGroup == 0 {
+		c.sendAlert(alertHandshakeFailure)
+		return errors.New("tls: no ECDHE curve supported by both client and server")
+	}
+	if clientKeyShare == nil {
+		if err := hs.doHelloRetryRequest(selectedGroup); err != nil {
+			return err
+		}
+		clientKeyShare = &hs.clientHello.keyShares[0]
+	}
+
+	if _, ok := curveForCurveID(selectedGroup); selectedGroup != X25519 && !ok {
+		c.sendAlert(alertInternalError)
+		return errors.New("tls: CurvePreferences includes unsupported curve")
+	}
+	params, err := generateECDHEParameters(c.config.rand(), selectedGroup)
+	if err != nil {
+		c.sendAlert(alertInternalError)
+		return err
+	}
+	hs.hello.serverShare = keyShare{group: selectedGroup, data: params.PublicKey()}
+	hs.sharedKey = params.SharedKey(clientKeyShare.data)
+	if hs.sharedKey == nil {
+		c.sendAlert(alertIllegalParameter)
+		return errors.New("tls: invalid client key share")
+	}
+
+	c.serverName = hs.clientHello.serverName
+	return nil
+}
+
+func (hs *serverHandshakeStateTLS13) checkForResumption() error {
+	c := hs.c
+
+	if c.config.SessionTicketsDisabled {
+		return nil
+	}
+
+	modeOK := false
+	for _, mode := range hs.clientHello.pskModes {
+		if mode == pskModeDHE {
+			modeOK = true
+			break
+		}
+	}
+	if !modeOK {
+		return nil
+	}
+
+	if len(hs.clientHello.pskIdentities) != len(hs.clientHello.pskBinders) {
+		c.sendAlert(alertIllegalParameter)
+		return errors.New("tls: invalid or missing PSK binders")
+	}
+	if len(hs.clientHello.pskIdentities) == 0 {
+		return nil
+	}
+
+	for i, identity := range hs.clientHello.pskIdentities {
+		if i >= maxClientPSKIdentities {
+			break
+		}
+
+		plaintext, _ := c.decryptTicket(identity.label)
+		if plaintext == nil {
+			continue
+		}
+		sessionState := new(sessionStateTLS13)
+		if ok := sessionState.unmarshal(plaintext); !ok {
+			continue
+		}
+
+		createdAt := time.Unix(int64(sessionState.createdAt), 0)
+		if c.config.time().Sub(createdAt) > maxSessionTicketLifetime {
+			continue
+		}
+
+		// We don't check the obfuscated ticket age because it's affected by
+		// clock skew and it's only a freshness signal useful for shrinking the
+		// window for replay attacks, which don't affect us as we don't do 0-RTT.
+
+		pskSuite := cipherSuiteTLS13ByID(sessionState.cipherSuite)
+		if pskSuite == nil || pskSuite.hash != hs.suite.hash {
+			continue
+		}
+
+		// PSK connections don't re-establish client certificates, but carry
+		// them over in the session ticket. Ensure the presence of client certs
+		// in the ticket is consistent with the configured requirements.
+		sessionHasClientCerts := len(sessionState.certificate.Certificate) != 0
+		needClientCerts := requiresClientCert(c.config.ClientAuth)
+		if needClientCerts && !sessionHasClientCerts {
+			continue
+		}
+		if sessionHasClientCerts && c.config.ClientAuth == NoClientCert {
+			continue
+		}
+
+		psk := hs.suite.expandLabel(sessionState.resumptionSecret, "resumption",
+			nil, hs.suite.hash.Size())
+		hs.earlySecret = hs.suite.extract(psk, nil)
+		binderKey := hs.suite.deriveSecret(hs.earlySecret, resumptionBinderLabel, nil)
+		// Clone the transcript in case a HelloRetryRequest was recorded.
+		transcript := cloneHash(hs.transcript, hs.suite.hash)
+		if transcript == nil {
+			c.sendAlert(alertInternalError)
+			return errors.New("tls: internal error: failed to clone hash")
+		}
+		transcript.Write(hs.clientHello.marshalWithoutBinders())
+		pskBinder := hs.suite.finishedHash(binderKey, transcript)
+		if !hmac.Equal(hs.clientHello.pskBinders[i], pskBinder) {
+			c.sendAlert(alertDecryptError)
+			return errors.New("tls: invalid PSK binder")
+		}
+
+		c.didResume = true
+		if err := c.processCertsFromClient(sessionState.certificate); err != nil {
+			return err
+		}
+
+		hs.hello.selectedIdentityPresent = true
+		hs.hello.selectedIdentity = uint16(i)
+		hs.usingPSK = true
+		return nil
+	}
+
+	return nil
+}
+
+// cloneHash uses the encoding.BinaryMarshaler and encoding.BinaryUnmarshaler
+// interfaces implemented by standard library hashes to clone the state of in
+// to a new instance of h. It returns nil if the operation fails.
+func cloneHash(in hash.Hash, h crypto.Hash) hash.Hash {
+	// Recreate the interface to avoid importing encoding.
+	type binaryMarshaler interface {
+		MarshalBinary() (data []byte, err error)
+		UnmarshalBinary(data []byte) error
+	}
+	marshaler, ok := in.(binaryMarshaler)
+	if !ok {
+		return nil
+	}
+	state, err := marshaler.MarshalBinary()
+	if err != nil {
+		return nil
+	}
+	out := h.New()
+	unmarshaler, ok := out.(binaryMarshaler)
+	if !ok {
+		return nil
+	}
+	if err := unmarshaler.UnmarshalBinary(state); err != nil {
+		return nil
+	}
+	return out
+}
+
+func (hs *serverHandshakeStateTLS13) pickCertificate() error {
+	c := hs.c
+
+	// Only one of PSK and certificates are used at a time.
+	if hs.usingPSK {
+		return nil
+	}
+
+	// signature_algorithms is required in TLS 1.3. See RFC 8446, Section 4.2.3.
+	if len(hs.clientHello.supportedSignatureAlgorithms) == 0 {
+		return c.sendAlert(alertMissingExtension)
+	}
+
+	certificate, err := c.config.getCertificate(clientHelloInfo(hs.ctx, c, hs.clientHello))
+	if err != nil {
+		if err == errNoCertificates {
+			c.sendAlert(alertUnrecognizedName)
+		} else {
+			c.sendAlert(alertInternalError)
+		}
+		return err
+	}
+	hs.sigAlg, err = selectSignatureScheme(c.vers, certificate, hs.clientHello.supportedSignatureAlgorithms)
+	if err != nil {
+		// getCertificate returned a certificate that is unsupported or
+		// incompatible with the client's signature algorithms.
+		c.sendAlert(alertHandshakeFailure)
+		return err
+	}
+	hs.cert = certificate
+
+	return nil
+}
+
+// sendDummyChangeCipherSpec sends a ChangeCipherSpec record for compatibility
+// with middleboxes that didn't implement TLS correctly. See RFC 8446, Appendix D.4.
+func (hs *serverHandshakeStateTLS13) sendDummyChangeCipherSpec() error {
+	if hs.sentDummyCCS {
+		return nil
+	}
+	hs.sentDummyCCS = true
+
+	_, err := hs.c.writeRecord(recordTypeChangeCipherSpec, []byte{1})
+	return err
+}
+
+func (hs *serverHandshakeStateTLS13) doHelloRetryRequest(selectedGroup CurveID) error {
+	c := hs.c
+
+	// The first ClientHello gets double-hashed into the transcript upon a
+	// HelloRetryRequest. See RFC 8446, Section 4.4.1.
+	hs.transcript.Write(hs.clientHello.marshal())
+	chHash := hs.transcript.Sum(nil)
+	hs.transcript.Reset()
+	hs.transcript.Write([]byte{typeMessageHash, 0, 0, uint8(len(chHash))})
+	hs.transcript.Write(chHash)
+
+	helloRetryRequest := &serverHelloMsg{
+		vers:              hs.hello.vers,
+		random:            helloRetryRequestRandom,
+		sessionId:         hs.hello.sessionId,
+		cipherSuite:       hs.hello.cipherSuite,
+		compressionMethod: hs.hello.compressionMethod,
+		supportedVersion:  hs.hello.supportedVersion,
+		selectedGroup:     selectedGroup,
+	}
+
+	hs.transcript.Write(helloRetryRequest.marshal())
+	if _, err := c.writeRecord(recordTypeHandshake, helloRetryRequest.marshal()); err != nil {
+		return err
+	}
+
+	if err := hs.sendDummyChangeCipherSpec(); err != nil {
+		return err
+	}
+
+	msg, err := c.readHandshake()
+	if err != nil {
+		return err
+	}
+
+	clientHello, ok := msg.(*clientHelloMsg)
+	if !ok {
+		c.sendAlert(alertUnexpectedMessage)
+		return unexpectedMessageError(clientHello, msg)
+	}
+
+	if len(clientHello.keyShares) != 1 || clientHello.keyShares[0].group != selectedGroup {
+		c.sendAlert(alertIllegalParameter)
+		return errors.New("tls: client sent invalid key share in second ClientHello")
+	}
+
+	if clientHello.earlyData {
+		c.sendAlert(alertIllegalParameter)
+		return errors.New("tls: client indicated early data in second ClientHello")
+	}
+
+	if illegalClientHelloChange(clientHello, hs.clientHello) {
+		c.sendAlert(alertIllegalParameter)
+		return errors.New("tls: client illegally modified second ClientHello")
+	}
+
+	hs.clientHello = clientHello
+	return nil
+}
+
+// illegalClientHelloChange reports whether the two ClientHello messages are
+// different, with the exception of the changes allowed before and after a
+// HelloRetryRequest. See RFC 8446, Section 4.1.2.
+func illegalClientHelloChange(ch, ch1 *clientHelloMsg) bool {
+	if len(ch.supportedVersions) != len(ch1.supportedVersions) ||
+		len(ch.cipherSuites) != len(ch1.cipherSuites) ||
+		len(ch.supportedCurves) != len(ch1.supportedCurves) ||
+		len(ch.supportedSignatureAlgorithms) != len(ch1.supportedSignatureAlgorithms) ||
+		len(ch.supportedSignatureAlgorithmsCert) != len(ch1.supportedSignatureAlgorithmsCert) ||
+		len(ch.alpnProtocols) != len(ch1.alpnProtocols) {
+		return true
+	}
+	for i := range ch.supportedVersions {
+		if ch.supportedVersions[i] != ch1.supportedVersions[i] {
+			return true
+		}
+	}
+	for i := range ch.cipherSuites {
+		if ch.cipherSuites[i] != ch1.cipherSuites[i] {
+			return true
+		}
+	}
+	for i := range ch.supportedCurves {
+		if ch.supportedCurves[i] != ch1.supportedCurves[i] {
+			return true
+		}
+	}
+	for i := range ch.supportedSignatureAlgorithms {
+		if ch.supportedSignatureAlgorithms[i] != ch1.supportedSignatureAlgorithms[i] {
+			return true
+		}
+	}
+	for i := range ch.supportedSignatureAlgorithmsCert {
+		if ch.supportedSignatureAlgorithmsCert[i] != ch1.supportedSignatureAlgorithmsCert[i] {
+			return true
+		}
+	}
+	for i := range ch.alpnProtocols {
+		if ch.alpnProtocols[i] != ch1.alpnProtocols[i] {
+			return true
+		}
+	}
+	return ch.vers != ch1.vers ||
+		!bytes.Equal(ch.random, ch1.random) ||
+		!bytes.Equal(ch.sessionId, ch1.sessionId) ||
+		!bytes.Equal(ch.compressionMethods, ch1.compressionMethods) ||
+		ch.serverName != ch1.serverName ||
+		ch.ocspStapling != ch1.ocspStapling ||
+		!bytes.Equal(ch.supportedPoints, ch1.supportedPoints) ||
+		ch.ticketSupported != ch1.ticketSupported ||
+		!bytes.Equal(ch.sessionTicket, ch1.sessionTicket) ||
+		ch.secureRenegotiationSupported != ch1.secureRenegotiationSupported ||
+		!bytes.Equal(ch.secureRenegotiation, ch1.secureRenegotiation) ||
+		ch.scts != ch1.scts ||
+		!bytes.Equal(ch.cookie, ch1.cookie) ||
+		!bytes.Equal(ch.pskModes, ch1.pskModes)
+}
+
+func (hs *serverHandshakeStateTLS13) sendServerParameters() error {
+	c := hs.c
+
+	hs.transcript.Write(hs.clientHello.marshal())
+	hs.transcript.Write(hs.hello.marshal())
+	if _, err := c.writeRecord(recordTypeHandshake, hs.hello.marshal()); err != nil {
+		return err
+	}
+
+	if err := hs.sendDummyChangeCipherSpec(); err != nil {
+		return err
+	}
+
+	earlySecret := hs.earlySecret
+	if earlySecret == nil {
+		earlySecret = hs.suite.extract(nil, nil)
+	}
+	hs.handshakeSecret = hs.suite.extract(hs.sharedKey,
+		hs.suite.deriveSecret(earlySecret, "derived", nil))
+
+	clientSecret := hs.suite.deriveSecret(hs.handshakeSecret,
+		clientHandshakeTrafficLabel, hs.transcript)
+	c.in.setTrafficSecret(hs.suite, clientSecret)
+	serverSecret := hs.suite.deriveSecret(hs.handshakeSecret,
+		serverHandshakeTrafficLabel, hs.transcript)
+	c.out.setTrafficSecret(hs.suite, serverSecret)
+
+	err := c.config.writeKeyLog(keyLogLabelClientHandshake, hs.clientHello.random, clientSecret)
+	if err != nil {
+		c.sendAlert(alertInternalError)
+		return err
+	}
+	err = c.config.writeKeyLog(keyLogLabelServerHandshake, hs.clientHello.random, serverSecret)
+	if err != nil {
+		c.sendAlert(alertInternalError)
+		return err
+	}
+
+	encryptedExtensions := new(encryptedExtensionsMsg)
+
+	selectedProto, err := negotiateALPN(c.config.NextProtos, hs.clientHello.alpnProtocols)
+	if err != nil {
+		c.sendAlert(alertNoApplicationProtocol)
+		return err
+	}
+	encryptedExtensions.alpnProtocol = selectedProto
+	c.clientProtocol = selectedProto
+
+	hs.transcript.Write(encryptedExtensions.marshal())
+	if _, err := c.writeRecord(recordTypeHandshake, encryptedExtensions.marshal()); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (hs *serverHandshakeStateTLS13) requestClientCert() bool {
+	return hs.c.config.ClientAuth >= RequestClientCert && !hs.usingPSK
+}
+
+func (hs *serverHandshakeStateTLS13) sendServerCertificate() error {
+	c := hs.c
+
+	// Only one of PSK and certificates are used at a time.
+	if hs.usingPSK {
+		return nil
+	}
+
+	if hs.requestClientCert() {
+		// Request a client certificate
+		certReq := new(certificateRequestMsgTLS13)
+		certReq.ocspStapling = true
+		certReq.scts = true
+		certReq.supportedSignatureAlgorithms = supportedSignatureAlgorithms()
+		if c.config.ClientCAs != nil {
+			certReq.certificateAuthorities = c.config.ClientCAs.Subjects()
+		}
+
+		hs.transcript.Write(certReq.marshal())
+		if _, err := c.writeRecord(recordTypeHandshake, certReq.marshal()); err != nil {
+			return err
+		}
+	}
+
+	certMsg := new(certificateMsgTLS13)
+
+	certMsg.certificate = *hs.cert
+	certMsg.scts = hs.clientHello.scts && len(hs.cert.SignedCertificateTimestamps) > 0
+	certMsg.ocspStapling = hs.clientHello.ocspStapling && len(hs.cert.OCSPStaple) > 0
+
+	hs.transcript.Write(certMsg.marshal())
+	if _, err := c.writeRecord(recordTypeHandshake, certMsg.marshal()); err != nil {
+		return err
+	}
+
+	certVerifyMsg := new(certificateVerifyMsg)
+	certVerifyMsg.hasSignatureAlgorithm = true
+	certVerifyMsg.signatureAlgorithm = hs.sigAlg
+
+	sigType, sigHash, err := typeAndHashFromSignatureScheme(hs.sigAlg)
+	if err != nil {
+		return c.sendAlert(alertInternalError)
+	}
+
+	signed := signedMessage(sigHash, serverSignatureContext, hs.transcript)
+	signOpts := crypto.SignerOpts(sigHash)
+	if sigType == signatureRSAPSS {
+		signOpts = &rsa.PSSOptions{SaltLength: rsa.PSSSaltLengthEqualsHash, Hash: sigHash}
+	}
+	sig, err := hs.cert.PrivateKey.(crypto.Signer).Sign(c.config.rand(), signed, signOpts)
+	if err != nil {
+		public := hs.cert.PrivateKey.(crypto.Signer).Public()
+		if rsaKey, ok := public.(*rsa.PublicKey); ok && sigType == signatureRSAPSS &&
+			rsaKey.N.BitLen()/8 < sigHash.Size()*2+2 { // key too small for RSA-PSS
+			c.sendAlert(alertHandshakeFailure)
+		} else {
+			c.sendAlert(alertInternalError)
+		}
+		return errors.New("tls: failed to sign handshake: " + err.Error())
+	}
+	certVerifyMsg.signature = sig
+
+	hs.transcript.Write(certVerifyMsg.marshal())
+	if _, err := c.writeRecord(recordTypeHandshake, certVerifyMsg.marshal()); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (hs *serverHandshakeStateTLS13) sendServerFinished() error {
+	c := hs.c
+
+	finished := &finishedMsg{
+		verifyData: hs.suite.finishedHash(c.out.trafficSecret, hs.transcript),
+	}
+
+	hs.transcript.Write(finished.marshal())
+	if _, err := c.writeRecord(recordTypeHandshake, finished.marshal()); err != nil {
+		return err
+	}
+
+	// Derive secrets that take context through the server Finished.
+
+	hs.masterSecret = hs.suite.extract(nil,
+		hs.suite.deriveSecret(hs.handshakeSecret, "derived", nil))
+
+	hs.trafficSecret = hs.suite.deriveSecret(hs.masterSecret,
+		clientApplicationTrafficLabel, hs.transcript)
+	serverSecret := hs.suite.deriveSecret(hs.masterSecret,
+		serverApplicationTrafficLabel, hs.transcript)
+	c.out.setTrafficSecret(hs.suite, serverSecret)
+
+	err := c.config.writeKeyLog(keyLogLabelClientTraffic, hs.clientHello.random, hs.trafficSecret)
+	if err != nil {
+		c.sendAlert(alertInternalError)
+		return err
+	}
+	err = c.config.writeKeyLog(keyLogLabelServerTraffic, hs.clientHello.random, serverSecret)
+	if err != nil {
+		c.sendAlert(alertInternalError)
+		return err
+	}
+
+	c.ekm = hs.suite.exportKeyingMaterial(hs.masterSecret, hs.transcript)
+
+	// If we did not request client certificates, at this point we can
+	// precompute the client finished and roll the transcript forward to send
+	// session tickets in our first flight.
+	if !hs.requestClientCert() {
+		if err := hs.sendSessionTickets(); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (hs *serverHandshakeStateTLS13) shouldSendSessionTickets() bool {
+	if hs.c.config.SessionTicketsDisabled {
+		return false
+	}
+
+	// Don't send tickets the client wouldn't use. See RFC 8446, Section 4.2.9.
+	for _, pskMode := range hs.clientHello.pskModes {
+		if pskMode == pskModeDHE {
+			return true
+		}
+	}
+	return false
+}
+
+func (hs *serverHandshakeStateTLS13) sendSessionTickets() error {
+	c := hs.c
+
+	hs.clientFinished = hs.suite.finishedHash(c.in.trafficSecret, hs.transcript)
+	finishedMsg := &finishedMsg{
+		verifyData: hs.clientFinished,
+	}
+	hs.transcript.Write(finishedMsg.marshal())
+
+	if !hs.shouldSendSessionTickets() {
+		return nil
+	}
+
+	resumptionSecret := hs.suite.deriveSecret(hs.masterSecret,
+		resumptionLabel, hs.transcript)
+
+	m := new(newSessionTicketMsgTLS13)
+
+	var certsFromClient [][]byte
+	for _, cert := range c.peerCertificates {
+		certsFromClient = append(certsFromClient, cert.Raw)
+	}
+	state := sessionStateTLS13{
+		cipherSuite:      hs.suite.id,
+		createdAt:        uint64(c.config.time().Unix()),
+		resumptionSecret: resumptionSecret,
+		certificate: Certificate{
+			Certificate:                 certsFromClient,
+			OCSPStaple:                  c.ocspResponse,
+			SignedCertificateTimestamps: c.scts,
+		},
+	}
+	var err error
+	m.label, err = c.encryptTicket(state.marshal())
+	if err != nil {
+		return err
+	}
+	m.lifetime = uint32(maxSessionTicketLifetime / time.Second)
+
+	// ticket_age_add is a random 32-bit value. See RFC 8446, section 4.6.1
+	// The value is not stored anywhere; we never need to check the ticket age
+	// because 0-RTT is not supported.
+	ageAdd := make([]byte, 4)
+	_, err = hs.c.config.rand().Read(ageAdd)
+	if err != nil {
+		return err
+	}
+	m.ageAdd = binary.LittleEndian.Uint32(ageAdd)
+
+	// ticket_nonce, which must be unique per connection, is always left at
+	// zero because we only ever send one ticket per connection.
+
+	if _, err := c.writeRecord(recordTypeHandshake, m.marshal()); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (hs *serverHandshakeStateTLS13) readClientCertificate() error {
+	c := hs.c
+
+	if !hs.requestClientCert() {
+		// Make sure the connection is still being verified whether or not
+		// the server requested a client certificate.
+		if c.config.VerifyConnection != nil {
+			if err := c.config.VerifyConnection(c.connectionStateLocked()); err != nil {
+				c.sendAlert(alertBadCertificate)
+				return err
+			}
+		}
+		return nil
+	}
+
+	// If we requested a client certificate, then the client must send a
+	// certificate message. If it's empty, no CertificateVerify is sent.
+
+	msg, err := c.readHandshake()
+	if err != nil {
+		return err
+	}
+
+	certMsg, ok := msg.(*certificateMsgTLS13)
+	if !ok {
+		c.sendAlert(alertUnexpectedMessage)
+		return unexpectedMessageError(certMsg, msg)
+	}
+	hs.transcript.Write(certMsg.marshal())
+
+	if err := c.processCertsFromClient(certMsg.certificate); err != nil {
+		return err
+	}
+
+	if c.config.VerifyConnection != nil {
+		if err := c.config.VerifyConnection(c.connectionStateLocked()); err != nil {
+			c.sendAlert(alertBadCertificate)
+			return err
+		}
+	}
+
+	if len(certMsg.certificate.Certificate) != 0 {
+		msg, err = c.readHandshake()
+		if err != nil {
+			return err
+		}
+
+		certVerify, ok := msg.(*certificateVerifyMsg)
+		if !ok {
+			c.sendAlert(alertUnexpectedMessage)
+			return unexpectedMessageError(certVerify, msg)
+		}
+
+		// See RFC 8446, Section 4.4.3.
+		if !isSupportedSignatureAlgorithm(certVerify.signatureAlgorithm, supportedSignatureAlgorithms()) {
+			c.sendAlert(alertIllegalParameter)
+			return errors.New("tls: client certificate used with invalid signature algorithm")
+		}
+		sigType, sigHash, err := typeAndHashFromSignatureScheme(certVerify.signatureAlgorithm)
+		if err != nil {
+			return c.sendAlert(alertInternalError)
+		}
+		if sigType == signaturePKCS1v15 || sigHash == crypto.SHA1 {
+			c.sendAlert(alertIllegalParameter)
+			return errors.New("tls: client certificate used with invalid signature algorithm")
+		}
+		signed := signedMessage(sigHash, clientSignatureContext, hs.transcript)
+		if err := verifyHandshakeSignature(sigType, c.peerCertificates[0].PublicKey,
+			sigHash, signed, certVerify.signature); err != nil {
+			c.sendAlert(alertDecryptError)
+			return errors.New("tls: invalid signature by the client certificate: " + err.Error())
+		}
+
+		hs.transcript.Write(certVerify.marshal())
+	}
+
+	// If we waited until the client certificates to send session tickets, we
+	// are ready to do it now.
+	if err := hs.sendSessionTickets(); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (hs *serverHandshakeStateTLS13) readClientFinished() error {
+	c := hs.c
+
+	msg, err := c.readHandshake()
+	if err != nil {
+		return err
+	}
+
+	finished, ok := msg.(*finishedMsg)
+	if !ok {
+		c.sendAlert(alertUnexpectedMessage)
+		return unexpectedMessageError(finished, msg)
+	}
+
+	if !hmac.Equal(hs.clientFinished, finished.verifyData) {
+		c.sendAlert(alertDecryptError)
+		return errors.New("tls: invalid client finished hash")
+	}
+
+	c.in.setTrafficSecret(hs.suite, hs.trafficSecret)
+
+	return nil
+}
diff --git a/contrib/go/_std_1.18/src/crypto/tls/key_agreement.go b/contrib/go/_std_1.19/src/crypto/tls/key_agreement.go
index c28a64f3a8..c28a64f3a8 100644
--- a/contrib/go/_std_1.18/src/crypto/tls/key_agreement.go
+++ b/contrib/go/_std_1.19/src/crypto/tls/key_agreement.go
diff --git a/contrib/go/_std_1.18/src/crypto/tls/key_schedule.go b/contrib/go/_std_1.19/src/crypto/tls/key_schedule.go
index 314016979a..314016979a 100644
--- a/contrib/go/_std_1.18/src/crypto/tls/key_schedule.go
+++ b/contrib/go/_std_1.19/src/crypto/tls/key_schedule.go
diff --git a/contrib/go/_std_1.19/src/crypto/tls/notboring.go b/contrib/go/_std_1.19/src/crypto/tls/notboring.go
new file mode 100644
index 0000000000..7d85b39c59
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/tls/notboring.go
@@ -0,0 +1,20 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !boringcrypto
+
+package tls
+
+func needFIPS() bool { return false }
+
+func supportedSignatureAlgorithms() []SignatureScheme {
+	return defaultSupportedSignatureAlgorithms
+}
+
+func fipsMinVersion(c *Config) uint16          { panic("fipsMinVersion") }
+func fipsMaxVersion(c *Config) uint16          { panic("fipsMaxVersion") }
+func fipsCurvePreferences(c *Config) []CurveID { panic("fipsCurvePreferences") }
+func fipsCipherSuites(c *Config) []uint16      { panic("fipsCipherSuites") }
+
+var fipsSupportedSignatureAlgorithms []SignatureScheme
diff --git a/contrib/go/_std_1.18/src/crypto/tls/prf.go b/contrib/go/_std_1.19/src/crypto/tls/prf.go
index 13bfa009ca..13bfa009ca 100644
--- a/contrib/go/_std_1.18/src/crypto/tls/prf.go
+++ b/contrib/go/_std_1.19/src/crypto/tls/prf.go
diff --git a/contrib/go/_std_1.18/src/crypto/tls/ticket.go b/contrib/go/_std_1.19/src/crypto/tls/ticket.go
index 6c1d20da20..6c1d20da20 100644
--- a/contrib/go/_std_1.18/src/crypto/tls/ticket.go
+++ b/contrib/go/_std_1.19/src/crypto/tls/ticket.go
diff --git a/contrib/go/_std_1.18/src/crypto/tls/tls.go b/contrib/go/_std_1.19/src/crypto/tls/tls.go
index b529c70523..b529c70523 100644
--- a/contrib/go/_std_1.18/src/crypto/tls/tls.go
+++ b/contrib/go/_std_1.19/src/crypto/tls/tls.go
diff --git a/contrib/go/_std_1.19/src/crypto/x509/cert_pool.go b/contrib/go/_std_1.19/src/crypto/x509/cert_pool.go
new file mode 100644
index 0000000000..e9b2c122b9
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/x509/cert_pool.go
@@ -0,0 +1,268 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package x509
+
+import (
+	"bytes"
+	"crypto/sha256"
+	"encoding/pem"
+	"sync"
+)
+
+type sum224 [sha256.Size224]byte
+
+// CertPool is a set of certificates.
+type CertPool struct {
+	byName map[string][]int // cert.RawSubject => index into lazyCerts
+
+	// lazyCerts contains funcs that return a certificate,
+	// lazily parsing/decompressing it as needed.
+	lazyCerts []lazyCert
+
+	// haveSum maps from sum224(cert.Raw) to true. It's used only
+	// for AddCert duplicate detection, to avoid CertPool.contains
+	// calls in the AddCert path (because the contains method can
+	// call getCert and otherwise negate savings from lazy getCert
+	// funcs).
+	haveSum map[sum224]bool
+
+	// systemPool indicates whether this is a special pool derived from the
+	// system roots. If it includes additional roots, it requires doing two
+	// verifications, one using the roots provided by the caller, and one using
+	// the system platform verifier.
+	systemPool bool
+}
+
+// lazyCert is minimal metadata about a Cert and a func to retrieve it
+// in its normal expanded *Certificate form.
+type lazyCert struct {
+	// rawSubject is the Certificate.RawSubject value.
+	// It's the same as the CertPool.byName key, but in []byte
+	// form to make CertPool.Subjects (as used by crypto/tls) do
+	// fewer allocations.
+	rawSubject []byte
+
+	// getCert returns the certificate.
+	//
+	// It is not meant to do network operations or anything else
+	// where a failure is likely; the func is meant to lazily
+	// parse/decompress data that is already known to be good. The
+	// error in the signature primarily is meant for use in the
+	// case where a cert file existed on local disk when the program
+	// started up is deleted later before it's read.
+	getCert func() (*Certificate, error)
+}
+
+// NewCertPool returns a new, empty CertPool.
+func NewCertPool() *CertPool {
+	return &CertPool{
+		byName:  make(map[string][]int),
+		haveSum: make(map[sum224]bool),
+	}
+}
+
+// len returns the number of certs in the set.
+// A nil set is a valid empty set.
+func (s *CertPool) len() int {
+	if s == nil {
+		return 0
+	}
+	return len(s.lazyCerts)
+}
+
+// cert returns cert index n in s.
+func (s *CertPool) cert(n int) (*Certificate, error) {
+	return s.lazyCerts[n].getCert()
+}
+
+// Clone returns a copy of s.
+func (s *CertPool) Clone() *CertPool {
+	p := &CertPool{
+		byName:     make(map[string][]int, len(s.byName)),
+		lazyCerts:  make([]lazyCert, len(s.lazyCerts)),
+		haveSum:    make(map[sum224]bool, len(s.haveSum)),
+		systemPool: s.systemPool,
+	}
+	for k, v := range s.byName {
+		indexes := make([]int, len(v))
+		copy(indexes, v)
+		p.byName[k] = indexes
+	}
+	for k := range s.haveSum {
+		p.haveSum[k] = true
+	}
+	copy(p.lazyCerts, s.lazyCerts)
+	return p
+}
+
+// SystemCertPool returns a copy of the system cert pool.
+//
+// On Unix systems other than macOS the environment variables SSL_CERT_FILE and
+// SSL_CERT_DIR can be used to override the system default locations for the SSL
+// certificate file and SSL certificate files directory, respectively. The
+// latter can be a colon-separated list.
+//
+// Any mutations to the returned pool are not written to disk and do not affect
+// any other pool returned by SystemCertPool.
+//
+// New changes in the system cert pool might not be reflected in subsequent calls.
+func SystemCertPool() (*CertPool, error) {
+	if sysRoots := systemRootsPool(); sysRoots != nil {
+		return sysRoots.Clone(), nil
+	}
+
+	return loadSystemRoots()
+}
+
+// findPotentialParents returns the indexes of certificates in s which might
+// have signed cert.
+func (s *CertPool) findPotentialParents(cert *Certificate) []*Certificate {
+	if s == nil {
+		return nil
+	}
+
+	// consider all candidates where cert.Issuer matches cert.Subject.
+	// when picking possible candidates the list is built in the order
+	// of match plausibility as to save cycles in buildChains:
+	//   AKID and SKID match
+	//   AKID present, SKID missing / AKID missing, SKID present
+	//   AKID and SKID don't match
+	var matchingKeyID, oneKeyID, mismatchKeyID []*Certificate
+	for _, c := range s.byName[string(cert.RawIssuer)] {
+		candidate, err := s.cert(c)
+		if err != nil {
+			continue
+		}
+		kidMatch := bytes.Equal(candidate.SubjectKeyId, cert.AuthorityKeyId)
+		switch {
+		case kidMatch:
+			matchingKeyID = append(matchingKeyID, candidate)
+		case (len(candidate.SubjectKeyId) == 0 && len(cert.AuthorityKeyId) > 0) ||
+			(len(candidate.SubjectKeyId) > 0 && len(cert.AuthorityKeyId) == 0):
+			oneKeyID = append(oneKeyID, candidate)
+		default:
+			mismatchKeyID = append(mismatchKeyID, candidate)
+		}
+	}
+
+	found := len(matchingKeyID) + len(oneKeyID) + len(mismatchKeyID)
+	if found == 0 {
+		return nil
+	}
+	candidates := make([]*Certificate, 0, found)
+	candidates = append(candidates, matchingKeyID...)
+	candidates = append(candidates, oneKeyID...)
+	candidates = append(candidates, mismatchKeyID...)
+	return candidates
+}
+
+func (s *CertPool) contains(cert *Certificate) bool {
+	if s == nil {
+		return false
+	}
+	return s.haveSum[sha256.Sum224(cert.Raw)]
+}
+
+// AddCert adds a certificate to a pool.
+func (s *CertPool) AddCert(cert *Certificate) {
+	if cert == nil {
+		panic("adding nil Certificate to CertPool")
+	}
+	s.addCertFunc(sha256.Sum224(cert.Raw), string(cert.RawSubject), func() (*Certificate, error) {
+		return cert, nil
+	})
+}
+
+// addCertFunc adds metadata about a certificate to a pool, along with
+// a func to fetch that certificate later when needed.
+//
+// The rawSubject is Certificate.RawSubject and must be non-empty.
+// The getCert func may be called 0 or more times.
+func (s *CertPool) addCertFunc(rawSum224 sum224, rawSubject string, getCert func() (*Certificate, error)) {
+	if getCert == nil {
+		panic("getCert can't be nil")
+	}
+
+	// Check that the certificate isn't being added twice.
+	if s.haveSum[rawSum224] {
+		return
+	}
+
+	s.haveSum[rawSum224] = true
+	s.lazyCerts = append(s.lazyCerts, lazyCert{
+		rawSubject: []byte(rawSubject),
+		getCert:    getCert,
+	})
+	s.byName[rawSubject] = append(s.byName[rawSubject], len(s.lazyCerts)-1)
+}
+
+// AppendCertsFromPEM attempts to parse a series of PEM encoded certificates.
+// It appends any certificates found to s and reports whether any certificates
+// were successfully parsed.
+//
+// On many Linux systems, /etc/ssl/cert.pem will contain the system wide set
+// of root CAs in a format suitable for this function.
+func (s *CertPool) AppendCertsFromPEM(pemCerts []byte) (ok bool) {
+	for len(pemCerts) > 0 {
+		var block *pem.Block
+		block, pemCerts = pem.Decode(pemCerts)
+		if block == nil {
+			break
+		}
+		if block.Type != "CERTIFICATE" || len(block.Headers) != 0 {
+			continue
+		}
+
+		certBytes := block.Bytes
+		cert, err := ParseCertificate(certBytes)
+		if err != nil {
+			continue
+		}
+		var lazyCert struct {
+			sync.Once
+			v *Certificate
+		}
+		s.addCertFunc(sha256.Sum224(cert.Raw), string(cert.RawSubject), func() (*Certificate, error) {
+			lazyCert.Do(func() {
+				// This can't fail, as the same bytes already parsed above.
+				lazyCert.v, _ = ParseCertificate(certBytes)
+				certBytes = nil
+			})
+			return lazyCert.v, nil
+		})
+		ok = true
+	}
+
+	return ok
+}
+
+// Subjects returns a list of the DER-encoded subjects of
+// all of the certificates in the pool.
+//
+// Deprecated: if s was returned by SystemCertPool, Subjects
+// will not include the system roots.
+func (s *CertPool) Subjects() [][]byte {
+	res := make([][]byte, s.len())
+	for i, lc := range s.lazyCerts {
+		res[i] = lc.rawSubject
+	}
+	return res
+}
+
+// Equal reports whether s and other are equal.
+func (s *CertPool) Equal(other *CertPool) bool {
+	if s == nil || other == nil {
+		return s == other
+	}
+	if s.systemPool != other.systemPool || len(s.haveSum) != len(other.haveSum) {
+		return false
+	}
+	for h := range s.haveSum {
+		if !other.haveSum[h] {
+			return false
+		}
+	}
+	return true
+}
diff --git a/contrib/go/_std_1.19/src/crypto/x509/internal/macos/corefoundation.go b/contrib/go/_std_1.19/src/crypto/x509/internal/macos/corefoundation.go
new file mode 100644
index 0000000000..2677ff706a
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/x509/internal/macos/corefoundation.go
@@ -0,0 +1,214 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build darwin
+
+// Package macOS provides cgo-less wrappers for Core Foundation and
+// Security.framework, similarly to how package syscall provides access to
+// libSystem.dylib.
+package macOS
+
+import (
+	"errors"
+	"internal/abi"
+	"reflect"
+	"runtime"
+	"time"
+	"unsafe"
+)
+
+// Core Foundation linker flags for the external linker. See Issue 42459.
+//
+//go:cgo_ldflag "-framework"
+//go:cgo_ldflag "CoreFoundation"
+
+// CFRef is an opaque reference to a Core Foundation object. It is a pointer,
+// but to memory not owned by Go, so not an unsafe.Pointer.
+type CFRef uintptr
+
+// CFDataToSlice returns a copy of the contents of data as a bytes slice.
+func CFDataToSlice(data CFRef) []byte {
+	length := CFDataGetLength(data)
+	ptr := CFDataGetBytePtr(data)
+	src := (*[1 << 20]byte)(unsafe.Pointer(ptr))[:length:length]
+	out := make([]byte, length)
+	copy(out, src)
+	return out
+}
+
+// CFStringToString returns a Go string representation of the passed
+// in CFString, or an empty string if it's invalid.
+func CFStringToString(ref CFRef) string {
+	data, err := CFStringCreateExternalRepresentation(ref)
+	if err != nil {
+		return ""
+	}
+	b := CFDataToSlice(data)
+	CFRelease(data)
+	return string(b)
+}
+
+// TimeToCFDateRef converts a time.Time into an apple CFDateRef
+func TimeToCFDateRef(t time.Time) CFRef {
+	secs := t.Sub(time.Date(2001, 1, 1, 0, 0, 0, 0, time.UTC)).Seconds()
+	ref := CFDateCreate(secs)
+	return ref
+}
+
+type CFString CFRef
+
+const kCFAllocatorDefault = 0
+const kCFStringEncodingUTF8 = 0x08000100
+
+//go:cgo_import_dynamic x509_CFDataCreate CFDataCreate "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
+
+func BytesToCFData(b []byte) CFRef {
+	p := unsafe.Pointer((*reflect.SliceHeader)(unsafe.Pointer(&b)).Data)
+	ret := syscall(abi.FuncPCABI0(x509_CFDataCreate_trampoline), kCFAllocatorDefault, uintptr(p), uintptr(len(b)), 0, 0, 0)
+	runtime.KeepAlive(p)
+	return CFRef(ret)
+}
+func x509_CFDataCreate_trampoline()
+
+//go:cgo_import_dynamic x509_CFStringCreateWithBytes CFStringCreateWithBytes "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
+
+// StringToCFString returns a copy of the UTF-8 contents of s as a new CFString.
+func StringToCFString(s string) CFString {
+	p := unsafe.Pointer((*reflect.StringHeader)(unsafe.Pointer(&s)).Data)
+	ret := syscall(abi.FuncPCABI0(x509_CFStringCreateWithBytes_trampoline), kCFAllocatorDefault, uintptr(p),
+		uintptr(len(s)), uintptr(kCFStringEncodingUTF8), 0 /* isExternalRepresentation */, 0)
+	runtime.KeepAlive(p)
+	return CFString(ret)
+}
+func x509_CFStringCreateWithBytes_trampoline()
+
+//go:cgo_import_dynamic x509_CFDictionaryGetValueIfPresent CFDictionaryGetValueIfPresent "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
+
+func CFDictionaryGetValueIfPresent(dict CFRef, key CFString) (value CFRef, ok bool) {
+	ret := syscall(abi.FuncPCABI0(x509_CFDictionaryGetValueIfPresent_trampoline), uintptr(dict), uintptr(key),
+		uintptr(unsafe.Pointer(&value)), 0, 0, 0)
+	if ret == 0 {
+		return 0, false
+	}
+	return value, true
+}
+func x509_CFDictionaryGetValueIfPresent_trampoline()
+
+const kCFNumberSInt32Type = 3
+
+//go:cgo_import_dynamic x509_CFNumberGetValue CFNumberGetValue "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
+
+func CFNumberGetValue(num CFRef) (int32, error) {
+	var value int32
+	ret := syscall(abi.FuncPCABI0(x509_CFNumberGetValue_trampoline), uintptr(num), uintptr(kCFNumberSInt32Type),
+		uintptr(unsafe.Pointer(&value)), 0, 0, 0)
+	if ret == 0 {
+		return 0, errors.New("CFNumberGetValue call failed")
+	}
+	return value, nil
+}
+func x509_CFNumberGetValue_trampoline()
+
+//go:cgo_import_dynamic x509_CFDataGetLength CFDataGetLength "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
+
+func CFDataGetLength(data CFRef) int {
+	ret := syscall(abi.FuncPCABI0(x509_CFDataGetLength_trampoline), uintptr(data), 0, 0, 0, 0, 0)
+	return int(ret)
+}
+func x509_CFDataGetLength_trampoline()
+
+//go:cgo_import_dynamic x509_CFDataGetBytePtr CFDataGetBytePtr "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
+
+func CFDataGetBytePtr(data CFRef) uintptr {
+	ret := syscall(abi.FuncPCABI0(x509_CFDataGetBytePtr_trampoline), uintptr(data), 0, 0, 0, 0, 0)
+	return ret
+}
+func x509_CFDataGetBytePtr_trampoline()
+
+//go:cgo_import_dynamic x509_CFArrayGetCount CFArrayGetCount "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
+
+func CFArrayGetCount(array CFRef) int {
+	ret := syscall(abi.FuncPCABI0(x509_CFArrayGetCount_trampoline), uintptr(array), 0, 0, 0, 0, 0)
+	return int(ret)
+}
+func x509_CFArrayGetCount_trampoline()
+
+//go:cgo_import_dynamic x509_CFArrayGetValueAtIndex CFArrayGetValueAtIndex "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
+
+func CFArrayGetValueAtIndex(array CFRef, index int) CFRef {
+	ret := syscall(abi.FuncPCABI0(x509_CFArrayGetValueAtIndex_trampoline), uintptr(array), uintptr(index), 0, 0, 0, 0)
+	return CFRef(ret)
+}
+func x509_CFArrayGetValueAtIndex_trampoline()
+
+//go:cgo_import_dynamic x509_CFEqual CFEqual "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
+
+func CFEqual(a, b CFRef) bool {
+	ret := syscall(abi.FuncPCABI0(x509_CFEqual_trampoline), uintptr(a), uintptr(b), 0, 0, 0, 0)
+	return ret == 1
+}
+func x509_CFEqual_trampoline()
+
+//go:cgo_import_dynamic x509_CFRelease CFRelease "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
+
+func CFRelease(ref CFRef) {
+	syscall(abi.FuncPCABI0(x509_CFRelease_trampoline), uintptr(ref), 0, 0, 0, 0, 0)
+}
+func x509_CFRelease_trampoline()
+
+//go:cgo_import_dynamic x509_CFArrayCreateMutable CFArrayCreateMutable "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
+
+func CFArrayCreateMutable() CFRef {
+	ret := syscall(abi.FuncPCABI0(x509_CFArrayCreateMutable_trampoline), kCFAllocatorDefault, 0, 0 /* kCFTypeArrayCallBacks */, 0, 0, 0)
+	return CFRef(ret)
+}
+func x509_CFArrayCreateMutable_trampoline()
+
+//go:cgo_import_dynamic x509_CFArrayAppendValue CFArrayAppendValue "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
+
+func CFArrayAppendValue(array CFRef, val CFRef) {
+	syscall(abi.FuncPCABI0(x509_CFArrayAppendValue_trampoline), uintptr(array), uintptr(val), 0, 0, 0, 0)
+}
+func x509_CFArrayAppendValue_trampoline()
+
+//go:cgo_import_dynamic x509_CFDateCreate CFDateCreate "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
+
+func CFDateCreate(seconds float64) CFRef {
+	ret := syscall(abi.FuncPCABI0(x509_CFDateCreate_trampoline), kCFAllocatorDefault, 0, 0, 0, 0, seconds)
+	return CFRef(ret)
+}
+func x509_CFDateCreate_trampoline()
+
+//go:cgo_import_dynamic x509_CFErrorCopyDescription CFErrorCopyDescription "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
+
+func CFErrorCopyDescription(errRef CFRef) CFRef {
+	ret := syscall(abi.FuncPCABI0(x509_CFErrorCopyDescription_trampoline), uintptr(errRef), 0, 0, 0, 0, 0)
+	return CFRef(ret)
+}
+func x509_CFErrorCopyDescription_trampoline()
+
+//go:cgo_import_dynamic x509_CFStringCreateExternalRepresentation CFStringCreateExternalRepresentation "/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation"
+
+func CFStringCreateExternalRepresentation(strRef CFRef) (CFRef, error) {
+	ret := syscall(abi.FuncPCABI0(x509_CFStringCreateExternalRepresentation_trampoline), kCFAllocatorDefault, uintptr(strRef), kCFStringEncodingUTF8, 0, 0, 0)
+	if ret == 0 {
+		return 0, errors.New("string can't be represented as UTF-8")
+	}
+	return CFRef(ret), nil
+}
+func x509_CFStringCreateExternalRepresentation_trampoline()
+
+// syscall is implemented in the runtime package (runtime/sys_darwin.go)
+func syscall(fn, a1, a2, a3, a4, a5 uintptr, f1 float64) uintptr
+
+// ReleaseCFArray iterates through an array, releasing its contents, and then
+// releases the array itself. This is necessary because we cannot, easily, set the
+// CFArrayCallBacks argument when creating CFArrays.
+func ReleaseCFArray(array CFRef) {
+	for i := 0; i < CFArrayGetCount(array); i++ {
+		ref := CFArrayGetValueAtIndex(array, i)
+		CFRelease(ref)
+	}
+	CFRelease(array)
+}
diff --git a/contrib/go/_std_1.18/src/crypto/x509/internal/macos/corefoundation.s b/contrib/go/_std_1.19/src/crypto/x509/internal/macos/corefoundation.s
index d69f72f795..d69f72f795 100644
--- a/contrib/go/_std_1.18/src/crypto/x509/internal/macos/corefoundation.s
+++ b/contrib/go/_std_1.19/src/crypto/x509/internal/macos/corefoundation.s
diff --git a/contrib/go/_std_1.19/src/crypto/x509/internal/macos/security.go b/contrib/go/_std_1.19/src/crypto/x509/internal/macos/security.go
new file mode 100644
index 0000000000..d8147ba8ba
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/x509/internal/macos/security.go
@@ -0,0 +1,240 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build darwin
+
+package macOS
+
+import (
+	"errors"
+	"fmt"
+	"internal/abi"
+	"strconv"
+	"unsafe"
+)
+
+// Security.framework linker flags for the external linker. See Issue 42459.
+//
+//go:cgo_ldflag "-framework"
+//go:cgo_ldflag "Security"
+
+// Based on https://opensource.apple.com/source/Security/Security-59306.41.2/base/Security.h
+
+type SecTrustSettingsResult int32
+
+const (
+	SecTrustSettingsResultInvalid SecTrustSettingsResult = iota
+	SecTrustSettingsResultTrustRoot
+	SecTrustSettingsResultTrustAsRoot
+	SecTrustSettingsResultDeny
+	SecTrustSettingsResultUnspecified
+)
+
+type SecTrustResultType int32
+
+const (
+	SecTrustResultInvalid SecTrustResultType = iota
+	SecTrustResultProceed
+	SecTrustResultConfirm // deprecated
+	SecTrustResultDeny
+	SecTrustResultUnspecified
+	SecTrustResultRecoverableTrustFailure
+	SecTrustResultFatalTrustFailure
+	SecTrustResultOtherError
+)
+
+type SecTrustSettingsDomain int32
+
+const (
+	SecTrustSettingsDomainUser SecTrustSettingsDomain = iota
+	SecTrustSettingsDomainAdmin
+	SecTrustSettingsDomainSystem
+)
+
+type OSStatus struct {
+	call   string
+	status int32
+}
+
+func (s OSStatus) Error() string {
+	return s.call + " error: " + strconv.Itoa(int(s.status))
+}
+
+// Dictionary keys are defined as build-time strings with CFSTR, but the Go
+// linker's internal linking mode can't handle CFSTR relocations. Create our
+// own dynamic strings instead and just never release them.
+//
+// Note that this might be the only thing that can break over time if
+// these values change, as the ABI arguably requires using the strings
+// pointed to by the symbols, not values that happen to be equal to them.
+
+var SecTrustSettingsResultKey = StringToCFString("kSecTrustSettingsResult")
+var SecTrustSettingsPolicy = StringToCFString("kSecTrustSettingsPolicy")
+var SecTrustSettingsPolicyString = StringToCFString("kSecTrustSettingsPolicyString")
+var SecPolicyOid = StringToCFString("SecPolicyOid")
+var SecPolicyAppleSSL = StringToCFString("1.2.840.113635.100.1.3") // defined by POLICYMACRO
+
+var ErrNoTrustSettings = errors.New("no trust settings found")
+
+const errSecNoTrustSettings = -25263
+
+//go:cgo_import_dynamic x509_SecTrustSettingsCopyCertificates SecTrustSettingsCopyCertificates "/System/Library/Frameworks/Security.framework/Versions/A/Security"
+
+func SecTrustSettingsCopyCertificates(domain SecTrustSettingsDomain) (certArray CFRef, err error) {
+	ret := syscall(abi.FuncPCABI0(x509_SecTrustSettingsCopyCertificates_trampoline), uintptr(domain),
+		uintptr(unsafe.Pointer(&certArray)), 0, 0, 0, 0)
+	if int32(ret) == errSecNoTrustSettings {
+		return 0, ErrNoTrustSettings
+	} else if ret != 0 {
+		return 0, OSStatus{"SecTrustSettingsCopyCertificates", int32(ret)}
+	}
+	return certArray, nil
+}
+func x509_SecTrustSettingsCopyCertificates_trampoline()
+
+const errSecItemNotFound = -25300
+
+//go:cgo_import_dynamic x509_SecTrustSettingsCopyTrustSettings SecTrustSettingsCopyTrustSettings "/System/Library/Frameworks/Security.framework/Versions/A/Security"
+
+func SecTrustSettingsCopyTrustSettings(cert CFRef, domain SecTrustSettingsDomain) (trustSettings CFRef, err error) {
+	ret := syscall(abi.FuncPCABI0(x509_SecTrustSettingsCopyTrustSettings_trampoline), uintptr(cert), uintptr(domain),
+		uintptr(unsafe.Pointer(&trustSettings)), 0, 0, 0)
+	if int32(ret) == errSecItemNotFound {
+		return 0, ErrNoTrustSettings
+	} else if ret != 0 {
+		return 0, OSStatus{"SecTrustSettingsCopyTrustSettings", int32(ret)}
+	}
+	return trustSettings, nil
+}
+func x509_SecTrustSettingsCopyTrustSettings_trampoline()
+
+//go:cgo_import_dynamic x509_SecPolicyCopyProperties SecPolicyCopyProperties "/System/Library/Frameworks/Security.framework/Versions/A/Security"
+
+func SecPolicyCopyProperties(policy CFRef) CFRef {
+	ret := syscall(abi.FuncPCABI0(x509_SecPolicyCopyProperties_trampoline), uintptr(policy), 0, 0, 0, 0, 0)
+	return CFRef(ret)
+}
+func x509_SecPolicyCopyProperties_trampoline()
+
+//go:cgo_import_dynamic x509_SecTrustCreateWithCertificates SecTrustCreateWithCertificates "/System/Library/Frameworks/Security.framework/Versions/A/Security"
+
+func SecTrustCreateWithCertificates(certs CFRef, policies CFRef) (CFRef, error) {
+	var trustObj CFRef
+	ret := syscall(abi.FuncPCABI0(x509_SecTrustCreateWithCertificates_trampoline), uintptr(certs), uintptr(policies),
+		uintptr(unsafe.Pointer(&trustObj)), 0, 0, 0)
+	if int32(ret) != 0 {
+		return 0, OSStatus{"SecTrustCreateWithCertificates", int32(ret)}
+	}
+	return trustObj, nil
+}
+func x509_SecTrustCreateWithCertificates_trampoline()
+
+//go:cgo_import_dynamic x509_SecCertificateCreateWithData SecCertificateCreateWithData "/System/Library/Frameworks/Security.framework/Versions/A/Security"
+
+func SecCertificateCreateWithData(b []byte) (CFRef, error) {
+	data := BytesToCFData(b)
+	defer CFRelease(data)
+	ret := syscall(abi.FuncPCABI0(x509_SecCertificateCreateWithData_trampoline), kCFAllocatorDefault, uintptr(data), 0, 0, 0, 0)
+	// Returns NULL if the data passed in the data parameter is not a valid
+	// DER-encoded X.509 certificate.
+	if ret == 0 {
+		return 0, errors.New("SecCertificateCreateWithData: invalid certificate")
+	}
+	return CFRef(ret), nil
+}
+func x509_SecCertificateCreateWithData_trampoline()
+
+//go:cgo_import_dynamic x509_SecPolicyCreateSSL SecPolicyCreateSSL "/System/Library/Frameworks/Security.framework/Versions/A/Security"
+
+func SecPolicyCreateSSL(name string) CFRef {
+	var hostname CFString
+	if name != "" {
+		hostname = StringToCFString(name)
+		defer CFRelease(CFRef(hostname))
+	}
+	ret := syscall(abi.FuncPCABI0(x509_SecPolicyCreateSSL_trampoline), 1 /* true */, uintptr(hostname), 0, 0, 0, 0)
+	return CFRef(ret)
+}
+func x509_SecPolicyCreateSSL_trampoline()
+
+//go:cgo_import_dynamic x509_SecTrustSetVerifyDate SecTrustSetVerifyDate "/System/Library/Frameworks/Security.framework/Versions/A/Security"
+
+func SecTrustSetVerifyDate(trustObj CFRef, dateRef CFRef) error {
+	ret := syscall(abi.FuncPCABI0(x509_SecTrustSetVerifyDate_trampoline), uintptr(trustObj), uintptr(dateRef), 0, 0, 0, 0)
+	if int32(ret) != 0 {
+		return OSStatus{"SecTrustSetVerifyDate", int32(ret)}
+	}
+	return nil
+}
+func x509_SecTrustSetVerifyDate_trampoline()
+
+//go:cgo_import_dynamic x509_SecTrustEvaluate SecTrustEvaluate "/System/Library/Frameworks/Security.framework/Versions/A/Security"
+
+func SecTrustEvaluate(trustObj CFRef) (CFRef, error) {
+	var result CFRef
+	ret := syscall(abi.FuncPCABI0(x509_SecTrustEvaluate_trampoline), uintptr(trustObj), uintptr(unsafe.Pointer(&result)), 0, 0, 0, 0)
+	if int32(ret) != 0 {
+		return 0, OSStatus{"SecTrustEvaluate", int32(ret)}
+	}
+	return CFRef(result), nil
+}
+func x509_SecTrustEvaluate_trampoline()
+
+//go:cgo_import_dynamic x509_SecTrustGetResult SecTrustGetResult "/System/Library/Frameworks/Security.framework/Versions/A/Security"
+
+func SecTrustGetResult(trustObj CFRef, result CFRef) (CFRef, CFRef, error) {
+	var chain, info CFRef
+	ret := syscall(abi.FuncPCABI0(x509_SecTrustGetResult_trampoline), uintptr(trustObj), uintptr(unsafe.Pointer(&result)),
+		uintptr(unsafe.Pointer(&chain)), uintptr(unsafe.Pointer(&info)), 0, 0)
+	if int32(ret) != 0 {
+		return 0, 0, OSStatus{"SecTrustGetResult", int32(ret)}
+	}
+	return chain, info, nil
+}
+func x509_SecTrustGetResult_trampoline()
+
+//go:cgo_import_dynamic x509_SecTrustEvaluateWithError SecTrustEvaluateWithError "/System/Library/Frameworks/Security.framework/Versions/A/Security"
+
+func SecTrustEvaluateWithError(trustObj CFRef) error {
+	var errRef CFRef
+	ret := syscall(abi.FuncPCABI0(x509_SecTrustEvaluateWithError_trampoline), uintptr(trustObj), uintptr(unsafe.Pointer(&errRef)), 0, 0, 0, 0)
+	if int32(ret) != 1 {
+		errStr := CFErrorCopyDescription(errRef)
+		err := fmt.Errorf("x509: %s", CFStringToString(errStr))
+		CFRelease(errRef)
+		CFRelease(errStr)
+		return err
+	}
+	return nil
+}
+func x509_SecTrustEvaluateWithError_trampoline()
+
+//go:cgo_import_dynamic x509_SecTrustGetCertificateCount SecTrustGetCertificateCount "/System/Library/Frameworks/Security.framework/Versions/A/Security"
+
+func SecTrustGetCertificateCount(trustObj CFRef) int {
+	ret := syscall(abi.FuncPCABI0(x509_SecTrustGetCertificateCount_trampoline), uintptr(trustObj), 0, 0, 0, 0, 0)
+	return int(ret)
+}
+func x509_SecTrustGetCertificateCount_trampoline()
+
+//go:cgo_import_dynamic x509_SecTrustGetCertificateAtIndex SecTrustGetCertificateAtIndex "/System/Library/Frameworks/Security.framework/Versions/A/Security"
+
+func SecTrustGetCertificateAtIndex(trustObj CFRef, i int) CFRef {
+	ret := syscall(abi.FuncPCABI0(x509_SecTrustGetCertificateAtIndex_trampoline), uintptr(trustObj), uintptr(i), 0, 0, 0, 0)
+	return CFRef(ret)
+}
+func x509_SecTrustGetCertificateAtIndex_trampoline()
+
+//go:cgo_import_dynamic x509_SecCertificateCopyData SecCertificateCopyData "/System/Library/Frameworks/Security.framework/Versions/A/Security"
+
+func SecCertificateCopyData(cert CFRef) ([]byte, error) {
+	ret := syscall(abi.FuncPCABI0(x509_SecCertificateCopyData_trampoline), uintptr(cert), 0, 0, 0, 0, 0)
+	if ret == 0 {
+		return nil, errors.New("x509: invalid certificate object")
+	}
+	b := CFDataToSlice(CFRef(ret))
+	CFRelease(CFRef(ret))
+	return b, nil
+}
+func x509_SecCertificateCopyData_trampoline()
diff --git a/contrib/go/_std_1.18/src/crypto/x509/internal/macos/security.s b/contrib/go/_std_1.19/src/crypto/x509/internal/macos/security.s
index 36f814f3cd..36f814f3cd 100644
--- a/contrib/go/_std_1.18/src/crypto/x509/internal/macos/security.s
+++ b/contrib/go/_std_1.19/src/crypto/x509/internal/macos/security.s
diff --git a/contrib/go/_std_1.19/src/crypto/x509/notboring.go b/contrib/go/_std_1.19/src/crypto/x509/notboring.go
new file mode 100644
index 0000000000..c83a7272c9
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/x509/notboring.go
@@ -0,0 +1,9 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !boringcrypto
+
+package x509
+
+func boringAllowCert(c *Certificate) bool { return true }
diff --git a/contrib/go/_std_1.19/src/crypto/x509/parser.go b/contrib/go/_std_1.19/src/crypto/x509/parser.go
new file mode 100644
index 0000000000..a2d3d80964
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/x509/parser.go
@@ -0,0 +1,1162 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+package x509
+
+import (
+	"bytes"
+	"crypto/dsa"
+	"crypto/ecdsa"
+	"crypto/ed25519"
+	"crypto/elliptic"
+	"crypto/rsa"
+	"crypto/x509/pkix"
+	"encoding/asn1"
+	"errors"
+	"fmt"
+	"math/big"
+	"net"
+	"net/url"
+	"strconv"
+	"strings"
+	"time"
+	"unicode/utf16"
+	"unicode/utf8"
+
+	"golang.org/x/crypto/cryptobyte"
+	cryptobyte_asn1 "golang.org/x/crypto/cryptobyte/asn1"
+)
+
+// isPrintable reports whether the given b is in the ASN.1 PrintableString set.
+// This is a simplified version of encoding/asn1.isPrintable.
+func isPrintable(b byte) bool {
+	return 'a' <= b && b <= 'z' ||
+		'A' <= b && b <= 'Z' ||
+		'0' <= b && b <= '9' ||
+		'\'' <= b && b <= ')' ||
+		'+' <= b && b <= '/' ||
+		b == ' ' ||
+		b == ':' ||
+		b == '=' ||
+		b == '?' ||
+		// This is technically not allowed in a PrintableString.
+		// However, x509 certificates with wildcard strings don't
+		// always use the correct string type so we permit it.
+		b == '*' ||
+		// This is not technically allowed either. However, not
+		// only is it relatively common, but there are also a
+		// handful of CA certificates that contain it. At least
+		// one of which will not expire until 2027.
+		b == '&'
+}
+
+// parseASN1String parses the ASN.1 string types T61String, PrintableString,
+// UTF8String, BMPString, IA5String, and NumericString. This is mostly copied
+// from the respective encoding/asn1.parse... methods, rather than just
+// increasing the API surface of that package.
+func parseASN1String(tag cryptobyte_asn1.Tag, value []byte) (string, error) {
+	switch tag {
+	case cryptobyte_asn1.T61String:
+		return string(value), nil
+	case cryptobyte_asn1.PrintableString:
+		for _, b := range value {
+			if !isPrintable(b) {
+				return "", errors.New("invalid PrintableString")
+			}
+		}
+		return string(value), nil
+	case cryptobyte_asn1.UTF8String:
+		if !utf8.Valid(value) {
+			return "", errors.New("invalid UTF-8 string")
+		}
+		return string(value), nil
+	case cryptobyte_asn1.Tag(asn1.TagBMPString):
+		if len(value)%2 != 0 {
+			return "", errors.New("invalid BMPString")
+		}
+
+		// Strip terminator if present.
+		if l := len(value); l >= 2 && value[l-1] == 0 && value[l-2] == 0 {
+			value = value[:l-2]
+		}
+
+		s := make([]uint16, 0, len(value)/2)
+		for len(value) > 0 {
+			s = append(s, uint16(value[0])<<8+uint16(value[1]))
+			value = value[2:]
+		}
+
+		return string(utf16.Decode(s)), nil
+	case cryptobyte_asn1.IA5String:
+		s := string(value)
+		if isIA5String(s) != nil {
+			return "", errors.New("invalid IA5String")
+		}
+		return s, nil
+	case cryptobyte_asn1.Tag(asn1.TagNumericString):
+		for _, b := range value {
+			if !('0' <= b && b <= '9' || b == ' ') {
+				return "", errors.New("invalid NumericString")
+			}
+		}
+		return string(value), nil
+	}
+	return "", fmt.Errorf("unsupported string type: %v", tag)
+}
+
+// parseName parses a DER encoded Name as defined in RFC 5280. We may
+// want to export this function in the future for use in crypto/tls.
+func parseName(raw cryptobyte.String) (*pkix.RDNSequence, error) {
+	if !raw.ReadASN1(&raw, cryptobyte_asn1.SEQUENCE) {
+		return nil, errors.New("x509: invalid RDNSequence")
+	}
+
+	var rdnSeq pkix.RDNSequence
+	for !raw.Empty() {
+		var rdnSet pkix.RelativeDistinguishedNameSET
+		var set cryptobyte.String
+		if !raw.ReadASN1(&set, cryptobyte_asn1.SET) {
+			return nil, errors.New("x509: invalid RDNSequence")
+		}
+		for !set.Empty() {
+			var atav cryptobyte.String
+			if !set.ReadASN1(&atav, cryptobyte_asn1.SEQUENCE) {
+				return nil, errors.New("x509: invalid RDNSequence: invalid attribute")
+			}
+			var attr pkix.AttributeTypeAndValue
+			if !atav.ReadASN1ObjectIdentifier(&attr.Type) {
+				return nil, errors.New("x509: invalid RDNSequence: invalid attribute type")
+			}
+			var rawValue cryptobyte.String
+			var valueTag cryptobyte_asn1.Tag
+			if !atav.ReadAnyASN1(&rawValue, &valueTag) {
+				return nil, errors.New("x509: invalid RDNSequence: invalid attribute value")
+			}
+			var err error
+			attr.Value, err = parseASN1String(valueTag, rawValue)
+			if err != nil {
+				return nil, fmt.Errorf("x509: invalid RDNSequence: invalid attribute value: %s", err)
+			}
+			rdnSet = append(rdnSet, attr)
+		}
+
+		rdnSeq = append(rdnSeq, rdnSet)
+	}
+
+	return &rdnSeq, nil
+}
+
+func parseAI(der cryptobyte.String) (pkix.AlgorithmIdentifier, error) {
+	ai := pkix.AlgorithmIdentifier{}
+	if !der.ReadASN1ObjectIdentifier(&ai.Algorithm) {
+		return ai, errors.New("x509: malformed OID")
+	}
+	if der.Empty() {
+		return ai, nil
+	}
+	var params cryptobyte.String
+	var tag cryptobyte_asn1.Tag
+	if !der.ReadAnyASN1Element(&params, &tag) {
+		return ai, errors.New("x509: malformed parameters")
+	}
+	ai.Parameters.Tag = int(tag)
+	ai.Parameters.FullBytes = params
+	return ai, nil
+}
+
+func parseTime(der *cryptobyte.String) (time.Time, error) {
+	var t time.Time
+	switch {
+	case der.PeekASN1Tag(cryptobyte_asn1.UTCTime):
+		if !der.ReadASN1UTCTime(&t) {
+			return t, errors.New("x509: malformed UTCTime")
+		}
+	case der.PeekASN1Tag(cryptobyte_asn1.GeneralizedTime):
+		if !der.ReadASN1GeneralizedTime(&t) {
+			return t, errors.New("x509: malformed GeneralizedTime")
+		}
+	default:
+		return t, errors.New("x509: unsupported time format")
+	}
+	return t, nil
+}
+
+func parseValidity(der cryptobyte.String) (time.Time, time.Time, error) {
+	notBefore, err := parseTime(&der)
+	if err != nil {
+		return time.Time{}, time.Time{}, err
+	}
+	notAfter, err := parseTime(&der)
+	if err != nil {
+		return time.Time{}, time.Time{}, err
+	}
+
+	return notBefore, notAfter, nil
+}
+
+func parseExtension(der cryptobyte.String) (pkix.Extension, error) {
+	var ext pkix.Extension
+	if !der.ReadASN1ObjectIdentifier(&ext.Id) {
+		return ext, errors.New("x509: malformed extension OID field")
+	}
+	if der.PeekASN1Tag(cryptobyte_asn1.BOOLEAN) {
+		if !der.ReadASN1Boolean(&ext.Critical) {
+			return ext, errors.New("x509: malformed extension critical field")
+		}
+	}
+	var val cryptobyte.String
+	if !der.ReadASN1(&val, cryptobyte_asn1.OCTET_STRING) {
+		return ext, errors.New("x509: malformed extension value field")
+	}
+	ext.Value = val
+	return ext, nil
+}
+
+func parsePublicKey(algo PublicKeyAlgorithm, keyData *publicKeyInfo) (any, error) {
+	der := cryptobyte.String(keyData.PublicKey.RightAlign())
+	switch algo {
+	case RSA:
+		// RSA public keys must have a NULL in the parameters.
+		// See RFC 3279, Section 2.3.1.
+		if !bytes.Equal(keyData.Algorithm.Parameters.FullBytes, asn1.NullBytes) {
+			return nil, errors.New("x509: RSA key missing NULL parameters")
+		}
+
+		p := &pkcs1PublicKey{N: new(big.Int)}
+		if !der.ReadASN1(&der, cryptobyte_asn1.SEQUENCE) {
+			return nil, errors.New("x509: invalid RSA public key")
+		}
+		if !der.ReadASN1Integer(p.N) {
+			return nil, errors.New("x509: invalid RSA modulus")
+		}
+		if !der.ReadASN1Integer(&p.E) {
+			return nil, errors.New("x509: invalid RSA public exponent")
+		}
+
+		if p.N.Sign() <= 0 {
+			return nil, errors.New("x509: RSA modulus is not a positive number")
+		}
+		if p.E <= 0 {
+			return nil, errors.New("x509: RSA public exponent is not a positive number")
+		}
+
+		pub := &rsa.PublicKey{
+			E: p.E,
+			N: p.N,
+		}
+		return pub, nil
+	case ECDSA:
+		paramsDer := cryptobyte.String(keyData.Algorithm.Parameters.FullBytes)
+		namedCurveOID := new(asn1.ObjectIdentifier)
+		if !paramsDer.ReadASN1ObjectIdentifier(namedCurveOID) {
+			return nil, errors.New("x509: invalid ECDSA parameters")
+		}
+		namedCurve := namedCurveFromOID(*namedCurveOID)
+		if namedCurve == nil {
+			return nil, errors.New("x509: unsupported elliptic curve")
+		}
+		x, y := elliptic.Unmarshal(namedCurve, der)
+		if x == nil {
+			return nil, errors.New("x509: failed to unmarshal elliptic curve point")
+		}
+		pub := &ecdsa.PublicKey{
+			Curve: namedCurve,
+			X:     x,
+			Y:     y,
+		}
+		return pub, nil
+	case Ed25519:
+		// RFC 8410, Section 3
+		// > For all of the OIDs, the parameters MUST be absent.
+		if len(keyData.Algorithm.Parameters.FullBytes) != 0 {
+			return nil, errors.New("x509: Ed25519 key encoded with illegal parameters")
+		}
+		if len(der) != ed25519.PublicKeySize {
+			return nil, errors.New("x509: wrong Ed25519 public key size")
+		}
+		return ed25519.PublicKey(der), nil
+	case DSA:
+		y := new(big.Int)
+		if !der.ReadASN1Integer(y) {
+			return nil, errors.New("x509: invalid DSA public key")
+		}
+		pub := &dsa.PublicKey{
+			Y: y,
+			Parameters: dsa.Parameters{
+				P: new(big.Int),
+				Q: new(big.Int),
+				G: new(big.Int),
+			},
+		}
+		paramsDer := cryptobyte.String(keyData.Algorithm.Parameters.FullBytes)
+		if !paramsDer.ReadASN1(&paramsDer, cryptobyte_asn1.SEQUENCE) ||
+			!paramsDer.ReadASN1Integer(pub.Parameters.P) ||
+			!paramsDer.ReadASN1Integer(pub.Parameters.Q) ||
+			!paramsDer.ReadASN1Integer(pub.Parameters.G) {
+			return nil, errors.New("x509: invalid DSA parameters")
+		}
+		if pub.Y.Sign() <= 0 || pub.Parameters.P.Sign() <= 0 ||
+			pub.Parameters.Q.Sign() <= 0 || pub.Parameters.G.Sign() <= 0 {
+			return nil, errors.New("x509: zero or negative DSA parameter")
+		}
+		return pub, nil
+	default:
+		return nil, nil
+	}
+}
+
+func parseKeyUsageExtension(der cryptobyte.String) (KeyUsage, error) {
+	var usageBits asn1.BitString
+	if !der.ReadASN1BitString(&usageBits) {
+		return 0, errors.New("x509: invalid key usage")
+	}
+
+	var usage int
+	for i := 0; i < 9; i++ {
+		if usageBits.At(i) != 0 {
+			usage |= 1 << uint(i)
+		}
+	}
+	return KeyUsage(usage), nil
+}
+
+func parseBasicConstraintsExtension(der cryptobyte.String) (bool, int, error) {
+	var isCA bool
+	if !der.ReadASN1(&der, cryptobyte_asn1.SEQUENCE) {
+		return false, 0, errors.New("x509: invalid basic constraints a")
+	}
+	if der.PeekASN1Tag(cryptobyte_asn1.BOOLEAN) {
+		if !der.ReadASN1Boolean(&isCA) {
+			return false, 0, errors.New("x509: invalid basic constraints b")
+		}
+	}
+	maxPathLen := -1
+	if !der.Empty() && der.PeekASN1Tag(cryptobyte_asn1.INTEGER) {
+		if !der.ReadASN1Integer(&maxPathLen) {
+			return false, 0, errors.New("x509: invalid basic constraints c")
+		}
+	}
+
+	// TODO: map out.MaxPathLen to 0 if it has the -1 default value? (Issue 19285)
+	return isCA, maxPathLen, nil
+}
+
+func forEachSAN(der cryptobyte.String, callback func(tag int, data []byte) error) error {
+	if !der.ReadASN1(&der, cryptobyte_asn1.SEQUENCE) {
+		return errors.New("x509: invalid subject alternative names")
+	}
+	for !der.Empty() {
+		var san cryptobyte.String
+		var tag cryptobyte_asn1.Tag
+		if !der.ReadAnyASN1(&san, &tag) {
+			return errors.New("x509: invalid subject alternative name")
+		}
+		if err := callback(int(tag^0x80), san); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func parseSANExtension(der cryptobyte.String) (dnsNames, emailAddresses []string, ipAddresses []net.IP, uris []*url.URL, err error) {
+	err = forEachSAN(der, func(tag int, data []byte) error {
+		switch tag {
+		case nameTypeEmail:
+			email := string(data)
+			if err := isIA5String(email); err != nil {
+				return errors.New("x509: SAN rfc822Name is malformed")
+			}
+			emailAddresses = append(emailAddresses, email)
+		case nameTypeDNS:
+			name := string(data)
+			if err := isIA5String(name); err != nil {
+				return errors.New("x509: SAN dNSName is malformed")
+			}
+			dnsNames = append(dnsNames, string(name))
+		case nameTypeURI:
+			uriStr := string(data)
+			if err := isIA5String(uriStr); err != nil {
+				return errors.New("x509: SAN uniformResourceIdentifier is malformed")
+			}
+			uri, err := url.Parse(uriStr)
+			if err != nil {
+				return fmt.Errorf("x509: cannot parse URI %q: %s", uriStr, err)
+			}
+			if len(uri.Host) > 0 {
+				if _, ok := domainToReverseLabels(uri.Host); !ok {
+					return fmt.Errorf("x509: cannot parse URI %q: invalid domain", uriStr)
+				}
+			}
+			uris = append(uris, uri)
+		case nameTypeIP:
+			switch len(data) {
+			case net.IPv4len, net.IPv6len:
+				ipAddresses = append(ipAddresses, data)
+			default:
+				return errors.New("x509: cannot parse IP address of length " + strconv.Itoa(len(data)))
+			}
+		}
+
+		return nil
+	})
+
+	return
+}
+
+func parseExtKeyUsageExtension(der cryptobyte.String) ([]ExtKeyUsage, []asn1.ObjectIdentifier, error) {
+	var extKeyUsages []ExtKeyUsage
+	var unknownUsages []asn1.ObjectIdentifier
+	if !der.ReadASN1(&der, cryptobyte_asn1.SEQUENCE) {
+		return nil, nil, errors.New("x509: invalid extended key usages")
+	}
+	for !der.Empty() {
+		var eku asn1.ObjectIdentifier
+		if !der.ReadASN1ObjectIdentifier(&eku) {
+			return nil, nil, errors.New("x509: invalid extended key usages")
+		}
+		if extKeyUsage, ok := extKeyUsageFromOID(eku); ok {
+			extKeyUsages = append(extKeyUsages, extKeyUsage)
+		} else {
+			unknownUsages = append(unknownUsages, eku)
+		}
+	}
+	return extKeyUsages, unknownUsages, nil
+}
+
+func parseCertificatePoliciesExtension(der cryptobyte.String) ([]asn1.ObjectIdentifier, error) {
+	var oids []asn1.ObjectIdentifier
+	if !der.ReadASN1(&der, cryptobyte_asn1.SEQUENCE) {
+		return nil, errors.New("x509: invalid certificate policies")
+	}
+	for !der.Empty() {
+		var cp cryptobyte.String
+		if !der.ReadASN1(&cp, cryptobyte_asn1.SEQUENCE) {
+			return nil, errors.New("x509: invalid certificate policies")
+		}
+		var oid asn1.ObjectIdentifier
+		if !cp.ReadASN1ObjectIdentifier(&oid) {
+			return nil, errors.New("x509: invalid certificate policies")
+		}
+		oids = append(oids, oid)
+	}
+
+	return oids, nil
+}
+
+// isValidIPMask reports whether mask consists of zero or more 1 bits, followed by zero bits.
+func isValidIPMask(mask []byte) bool {
+	seenZero := false
+
+	for _, b := range mask {
+		if seenZero {
+			if b != 0 {
+				return false
+			}
+
+			continue
+		}
+
+		switch b {
+		case 0x00, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe:
+			seenZero = true
+		case 0xff:
+		default:
+			return false
+		}
+	}
+
+	return true
+}
+
+func parseNameConstraintsExtension(out *Certificate, e pkix.Extension) (unhandled bool, err error) {
+	// RFC 5280, 4.2.1.10
+
+	// NameConstraints ::= SEQUENCE {
+	//      permittedSubtrees       [0]     GeneralSubtrees OPTIONAL,
+	//      excludedSubtrees        [1]     GeneralSubtrees OPTIONAL }
+	//
+	// GeneralSubtrees ::= SEQUENCE SIZE (1..MAX) OF GeneralSubtree
+	//
+	// GeneralSubtree ::= SEQUENCE {
+	//      base                    GeneralName,
+	//      minimum         [0]     BaseDistance DEFAULT 0,
+	//      maximum         [1]     BaseDistance OPTIONAL }
+	//
+	// BaseDistance ::= INTEGER (0..MAX)
+
+	outer := cryptobyte.String(e.Value)
+	var toplevel, permitted, excluded cryptobyte.String
+	var havePermitted, haveExcluded bool
+	if !outer.ReadASN1(&toplevel, cryptobyte_asn1.SEQUENCE) ||
+		!outer.Empty() ||
+		!toplevel.ReadOptionalASN1(&permitted, &havePermitted, cryptobyte_asn1.Tag(0).ContextSpecific().Constructed()) ||
+		!toplevel.ReadOptionalASN1(&excluded, &haveExcluded, cryptobyte_asn1.Tag(1).ContextSpecific().Constructed()) ||
+		!toplevel.Empty() {
+		return false, errors.New("x509: invalid NameConstraints extension")
+	}
+
+	if !havePermitted && !haveExcluded || len(permitted) == 0 && len(excluded) == 0 {
+		// From RFC 5280, Section 4.2.1.10:
+		//   “either the permittedSubtrees field
+		//   or the excludedSubtrees MUST be
+		//   present”
+		return false, errors.New("x509: empty name constraints extension")
+	}
+
+	getValues := func(subtrees cryptobyte.String) (dnsNames []string, ips []*net.IPNet, emails, uriDomains []string, err error) {
+		for !subtrees.Empty() {
+			var seq, value cryptobyte.String
+			var tag cryptobyte_asn1.Tag
+			if !subtrees.ReadASN1(&seq, cryptobyte_asn1.SEQUENCE) ||
+				!seq.ReadAnyASN1(&value, &tag) {
+				return nil, nil, nil, nil, fmt.Errorf("x509: invalid NameConstraints extension")
+			}
+
+			var (
+				dnsTag   = cryptobyte_asn1.Tag(2).ContextSpecific()
+				emailTag = cryptobyte_asn1.Tag(1).ContextSpecific()
+				ipTag    = cryptobyte_asn1.Tag(7).ContextSpecific()
+				uriTag   = cryptobyte_asn1.Tag(6).ContextSpecific()
+			)
+
+			switch tag {
+			case dnsTag:
+				domain := string(value)
+				if err := isIA5String(domain); err != nil {
+					return nil, nil, nil, nil, errors.New("x509: invalid constraint value: " + err.Error())
+				}
+
+				trimmedDomain := domain
+				if len(trimmedDomain) > 0 && trimmedDomain[0] == '.' {
+					// constraints can have a leading
+					// period to exclude the domain
+					// itself, but that's not valid in a
+					// normal domain name.
+					trimmedDomain = trimmedDomain[1:]
+				}
+				if _, ok := domainToReverseLabels(trimmedDomain); !ok {
+					return nil, nil, nil, nil, fmt.Errorf("x509: failed to parse dnsName constraint %q", domain)
+				}
+				dnsNames = append(dnsNames, domain)
+
+			case ipTag:
+				l := len(value)
+				var ip, mask []byte
+
+				switch l {
+				case 8:
+					ip = value[:4]
+					mask = value[4:]
+
+				case 32:
+					ip = value[:16]
+					mask = value[16:]
+
+				default:
+					return nil, nil, nil, nil, fmt.Errorf("x509: IP constraint contained value of length %d", l)
+				}
+
+				if !isValidIPMask(mask) {
+					return nil, nil, nil, nil, fmt.Errorf("x509: IP constraint contained invalid mask %x", mask)
+				}
+
+				ips = append(ips, &net.IPNet{IP: net.IP(ip), Mask: net.IPMask(mask)})
+
+			case emailTag:
+				constraint := string(value)
+				if err := isIA5String(constraint); err != nil {
+					return nil, nil, nil, nil, errors.New("x509: invalid constraint value: " + err.Error())
+				}
+
+				// If the constraint contains an @ then
+				// it specifies an exact mailbox name.
+				if strings.Contains(constraint, "@") {
+					if _, ok := parseRFC2821Mailbox(constraint); !ok {
+						return nil, nil, nil, nil, fmt.Errorf("x509: failed to parse rfc822Name constraint %q", constraint)
+					}
+				} else {
+					// Otherwise it's a domain name.
+					domain := constraint
+					if len(domain) > 0 && domain[0] == '.' {
+						domain = domain[1:]
+					}
+					if _, ok := domainToReverseLabels(domain); !ok {
+						return nil, nil, nil, nil, fmt.Errorf("x509: failed to parse rfc822Name constraint %q", constraint)
+					}
+				}
+				emails = append(emails, constraint)
+
+			case uriTag:
+				domain := string(value)
+				if err := isIA5String(domain); err != nil {
+					return nil, nil, nil, nil, errors.New("x509: invalid constraint value: " + err.Error())
+				}
+
+				if net.ParseIP(domain) != nil {
+					return nil, nil, nil, nil, fmt.Errorf("x509: failed to parse URI constraint %q: cannot be IP address", domain)
+				}
+
+				trimmedDomain := domain
+				if len(trimmedDomain) > 0 && trimmedDomain[0] == '.' {
+					// constraints can have a leading
+					// period to exclude the domain itself,
+					// but that's not valid in a normal
+					// domain name.
+					trimmedDomain = trimmedDomain[1:]
+				}
+				if _, ok := domainToReverseLabels(trimmedDomain); !ok {
+					return nil, nil, nil, nil, fmt.Errorf("x509: failed to parse URI constraint %q", domain)
+				}
+				uriDomains = append(uriDomains, domain)
+
+			default:
+				unhandled = true
+			}
+		}
+
+		return dnsNames, ips, emails, uriDomains, nil
+	}
+
+	if out.PermittedDNSDomains, out.PermittedIPRanges, out.PermittedEmailAddresses, out.PermittedURIDomains, err = getValues(permitted); err != nil {
+		return false, err
+	}
+	if out.ExcludedDNSDomains, out.ExcludedIPRanges, out.ExcludedEmailAddresses, out.ExcludedURIDomains, err = getValues(excluded); err != nil {
+		return false, err
+	}
+	out.PermittedDNSDomainsCritical = e.Critical
+
+	return unhandled, nil
+}
+
+func processExtensions(out *Certificate) error {
+	var err error
+	for _, e := range out.Extensions {
+		unhandled := false
+
+		if len(e.Id) == 4 && e.Id[0] == 2 && e.Id[1] == 5 && e.Id[2] == 29 {
+			switch e.Id[3] {
+			case 15:
+				out.KeyUsage, err = parseKeyUsageExtension(e.Value)
+				if err != nil {
+					return err
+				}
+			case 19:
+				out.IsCA, out.MaxPathLen, err = parseBasicConstraintsExtension(e.Value)
+				if err != nil {
+					return err
+				}
+				out.BasicConstraintsValid = true
+				out.MaxPathLenZero = out.MaxPathLen == 0
+			case 17:
+				out.DNSNames, out.EmailAddresses, out.IPAddresses, out.URIs, err = parseSANExtension(e.Value)
+				if err != nil {
+					return err
+				}
+
+				if len(out.DNSNames) == 0 && len(out.EmailAddresses) == 0 && len(out.IPAddresses) == 0 && len(out.URIs) == 0 {
+					// If we didn't parse anything then we do the critical check, below.
+					unhandled = true
+				}
+
+			case 30:
+				unhandled, err = parseNameConstraintsExtension(out, e)
+				if err != nil {
+					return err
+				}
+
+			case 31:
+				// RFC 5280, 4.2.1.13
+
+				// CRLDistributionPoints ::= SEQUENCE SIZE (1..MAX) OF DistributionPoint
+				//
+				// DistributionPoint ::= SEQUENCE {
+				//     distributionPoint       [0]     DistributionPointName OPTIONAL,
+				//     reasons                 [1]     ReasonFlags OPTIONAL,
+				//     cRLIssuer               [2]     GeneralNames OPTIONAL }
+				//
+				// DistributionPointName ::= CHOICE {
+				//     fullName                [0]     GeneralNames,
+				//     nameRelativeToCRLIssuer [1]     RelativeDistinguishedName }
+				val := cryptobyte.String(e.Value)
+				if !val.ReadASN1(&val, cryptobyte_asn1.SEQUENCE) {
+					return errors.New("x509: invalid CRL distribution points")
+				}
+				for !val.Empty() {
+					var dpDER cryptobyte.String
+					if !val.ReadASN1(&dpDER, cryptobyte_asn1.SEQUENCE) {
+						return errors.New("x509: invalid CRL distribution point")
+					}
+					var dpNameDER cryptobyte.String
+					var dpNamePresent bool
+					if !dpDER.ReadOptionalASN1(&dpNameDER, &dpNamePresent, cryptobyte_asn1.Tag(0).Constructed().ContextSpecific()) {
+						return errors.New("x509: invalid CRL distribution point")
+					}
+					if !dpNamePresent {
+						continue
+					}
+					if !dpNameDER.ReadASN1(&dpNameDER, cryptobyte_asn1.Tag(0).Constructed().ContextSpecific()) {
+						return errors.New("x509: invalid CRL distribution point")
+					}
+					for !dpNameDER.Empty() {
+						if !dpNameDER.PeekASN1Tag(cryptobyte_asn1.Tag(6).ContextSpecific()) {
+							break
+						}
+						var uri cryptobyte.String
+						if !dpNameDER.ReadASN1(&uri, cryptobyte_asn1.Tag(6).ContextSpecific()) {
+							return errors.New("x509: invalid CRL distribution point")
+						}
+						out.CRLDistributionPoints = append(out.CRLDistributionPoints, string(uri))
+					}
+				}
+
+			case 35:
+				// RFC 5280, 4.2.1.1
+				val := cryptobyte.String(e.Value)
+				var akid cryptobyte.String
+				if !val.ReadASN1(&akid, cryptobyte_asn1.SEQUENCE) {
+					return errors.New("x509: invalid authority key identifier")
+				}
+				if akid.PeekASN1Tag(cryptobyte_asn1.Tag(0).ContextSpecific()) {
+					if !akid.ReadASN1(&akid, cryptobyte_asn1.Tag(0).ContextSpecific()) {
+						return errors.New("x509: invalid authority key identifier")
+					}
+					out.AuthorityKeyId = akid
+				}
+			case 37:
+				out.ExtKeyUsage, out.UnknownExtKeyUsage, err = parseExtKeyUsageExtension(e.Value)
+				if err != nil {
+					return err
+				}
+			case 14:
+				// RFC 5280, 4.2.1.2
+				val := cryptobyte.String(e.Value)
+				var skid cryptobyte.String
+				if !val.ReadASN1(&skid, cryptobyte_asn1.OCTET_STRING) {
+					return errors.New("x509: invalid subject key identifier")
+				}
+				out.SubjectKeyId = skid
+			case 32:
+				out.PolicyIdentifiers, err = parseCertificatePoliciesExtension(e.Value)
+				if err != nil {
+					return err
+				}
+			default:
+				// Unknown extensions are recorded if critical.
+				unhandled = true
+			}
+		} else if e.Id.Equal(oidExtensionAuthorityInfoAccess) {
+			// RFC 5280 4.2.2.1: Authority Information Access
+			val := cryptobyte.String(e.Value)
+			if !val.ReadASN1(&val, cryptobyte_asn1.SEQUENCE) {
+				return errors.New("x509: invalid authority info access")
+			}
+			for !val.Empty() {
+				var aiaDER cryptobyte.String
+				if !val.ReadASN1(&aiaDER, cryptobyte_asn1.SEQUENCE) {
+					return errors.New("x509: invalid authority info access")
+				}
+				var method asn1.ObjectIdentifier
+				if !aiaDER.ReadASN1ObjectIdentifier(&method) {
+					return errors.New("x509: invalid authority info access")
+				}
+				if !aiaDER.PeekASN1Tag(cryptobyte_asn1.Tag(6).ContextSpecific()) {
+					continue
+				}
+				if !aiaDER.ReadASN1(&aiaDER, cryptobyte_asn1.Tag(6).ContextSpecific()) {
+					return errors.New("x509: invalid authority info access")
+				}
+				switch {
+				case method.Equal(oidAuthorityInfoAccessOcsp):
+					out.OCSPServer = append(out.OCSPServer, string(aiaDER))
+				case method.Equal(oidAuthorityInfoAccessIssuers):
+					out.IssuingCertificateURL = append(out.IssuingCertificateURL, string(aiaDER))
+				}
+			}
+		} else {
+			// Unknown extensions are recorded if critical.
+			unhandled = true
+		}
+
+		if e.Critical && unhandled {
+			out.UnhandledCriticalExtensions = append(out.UnhandledCriticalExtensions, e.Id)
+		}
+	}
+
+	return nil
+}
+
+func parseCertificate(der []byte) (*Certificate, error) {
+	cert := &Certificate{}
+
+	input := cryptobyte.String(der)
+	// we read the SEQUENCE including length and tag bytes so that
+	// we can populate Certificate.Raw, before unwrapping the
+	// SEQUENCE so it can be operated on
+	if !input.ReadASN1Element(&input, cryptobyte_asn1.SEQUENCE) {
+		return nil, errors.New("x509: malformed certificate")
+	}
+	cert.Raw = input
+	if !input.ReadASN1(&input, cryptobyte_asn1.SEQUENCE) {
+		return nil, errors.New("x509: malformed certificate")
+	}
+
+	var tbs cryptobyte.String
+	// do the same trick again as above to extract the raw
+	// bytes for Certificate.RawTBSCertificate
+	if !input.ReadASN1Element(&tbs, cryptobyte_asn1.SEQUENCE) {
+		return nil, errors.New("x509: malformed tbs certificate")
+	}
+	cert.RawTBSCertificate = tbs
+	if !tbs.ReadASN1(&tbs, cryptobyte_asn1.SEQUENCE) {
+		return nil, errors.New("x509: malformed tbs certificate")
+	}
+
+	if !tbs.ReadOptionalASN1Integer(&cert.Version, cryptobyte_asn1.Tag(0).Constructed().ContextSpecific(), 0) {
+		return nil, errors.New("x509: malformed version")
+	}
+	if cert.Version < 0 {
+		return nil, errors.New("x509: malformed version")
+	}
+	// for backwards compat reasons Version is one-indexed,
+	// rather than zero-indexed as defined in 5280
+	cert.Version++
+	if cert.Version > 3 {
+		return nil, errors.New("x509: invalid version")
+	}
+
+	serial := new(big.Int)
+	if !tbs.ReadASN1Integer(serial) {
+		return nil, errors.New("x509: malformed serial number")
+	}
+	// we ignore the presence of negative serial numbers because
+	// of their prevalence, despite them being invalid
+	// TODO(rolandshoemaker): revisit this decision, there are currently
+	// only 10 trusted certificates with negative serial numbers
+	// according to censys.io.
+	cert.SerialNumber = serial
+
+	var sigAISeq cryptobyte.String
+	if !tbs.ReadASN1(&sigAISeq, cryptobyte_asn1.SEQUENCE) {
+		return nil, errors.New("x509: malformed signature algorithm identifier")
+	}
+	// Before parsing the inner algorithm identifier, extract
+	// the outer algorithm identifier and make sure that they
+	// match.
+	var outerSigAISeq cryptobyte.String
+	if !input.ReadASN1(&outerSigAISeq, cryptobyte_asn1.SEQUENCE) {
+		return nil, errors.New("x509: malformed algorithm identifier")
+	}
+	if !bytes.Equal(outerSigAISeq, sigAISeq) {
+		return nil, errors.New("x509: inner and outer signature algorithm identifiers don't match")
+	}
+	sigAI, err := parseAI(sigAISeq)
+	if err != nil {
+		return nil, err
+	}
+	cert.SignatureAlgorithm = getSignatureAlgorithmFromAI(sigAI)
+
+	var issuerSeq cryptobyte.String
+	if !tbs.ReadASN1Element(&issuerSeq, cryptobyte_asn1.SEQUENCE) {
+		return nil, errors.New("x509: malformed issuer")
+	}
+	cert.RawIssuer = issuerSeq
+	issuerRDNs, err := parseName(issuerSeq)
+	if err != nil {
+		return nil, err
+	}
+	cert.Issuer.FillFromRDNSequence(issuerRDNs)
+
+	var validity cryptobyte.String
+	if !tbs.ReadASN1(&validity, cryptobyte_asn1.SEQUENCE) {
+		return nil, errors.New("x509: malformed validity")
+	}
+	cert.NotBefore, cert.NotAfter, err = parseValidity(validity)
+	if err != nil {
+		return nil, err
+	}
+
+	var subjectSeq cryptobyte.String
+	if !tbs.ReadASN1Element(&subjectSeq, cryptobyte_asn1.SEQUENCE) {
+		return nil, errors.New("x509: malformed issuer")
+	}
+	cert.RawSubject = subjectSeq
+	subjectRDNs, err := parseName(subjectSeq)
+	if err != nil {
+		return nil, err
+	}
+	cert.Subject.FillFromRDNSequence(subjectRDNs)
+
+	var spki cryptobyte.String
+	if !tbs.ReadASN1Element(&spki, cryptobyte_asn1.SEQUENCE) {
+		return nil, errors.New("x509: malformed spki")
+	}
+	cert.RawSubjectPublicKeyInfo = spki
+	if !spki.ReadASN1(&spki, cryptobyte_asn1.SEQUENCE) {
+		return nil, errors.New("x509: malformed spki")
+	}
+	var pkAISeq cryptobyte.String
+	if !spki.ReadASN1(&pkAISeq, cryptobyte_asn1.SEQUENCE) {
+		return nil, errors.New("x509: malformed public key algorithm identifier")
+	}
+	pkAI, err := parseAI(pkAISeq)
+	if err != nil {
+		return nil, err
+	}
+	cert.PublicKeyAlgorithm = getPublicKeyAlgorithmFromOID(pkAI.Algorithm)
+	var spk asn1.BitString
+	if !spki.ReadASN1BitString(&spk) {
+		return nil, errors.New("x509: malformed subjectPublicKey")
+	}
+	cert.PublicKey, err = parsePublicKey(cert.PublicKeyAlgorithm, &publicKeyInfo{
+		Algorithm: pkAI,
+		PublicKey: spk,
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	if cert.Version > 1 {
+		if !tbs.SkipOptionalASN1(cryptobyte_asn1.Tag(1).ContextSpecific()) {
+			return nil, errors.New("x509: malformed issuerUniqueID")
+		}
+		if !tbs.SkipOptionalASN1(cryptobyte_asn1.Tag(2).ContextSpecific()) {
+			return nil, errors.New("x509: malformed subjectUniqueID")
+		}
+		if cert.Version == 3 {
+			var extensions cryptobyte.String
+			var present bool
+			if !tbs.ReadOptionalASN1(&extensions, &present, cryptobyte_asn1.Tag(3).Constructed().ContextSpecific()) {
+				return nil, errors.New("x509: malformed extensions")
+			}
+			if present {
+				seenExts := make(map[string]bool)
+				if !extensions.ReadASN1(&extensions, cryptobyte_asn1.SEQUENCE) {
+					return nil, errors.New("x509: malformed extensions")
+				}
+				for !extensions.Empty() {
+					var extension cryptobyte.String
+					if !extensions.ReadASN1(&extension, cryptobyte_asn1.SEQUENCE) {
+						return nil, errors.New("x509: malformed extension")
+					}
+					ext, err := parseExtension(extension)
+					if err != nil {
+						return nil, err
+					}
+					oidStr := ext.Id.String()
+					if seenExts[oidStr] {
+						return nil, errors.New("x509: certificate contains duplicate extensions")
+					}
+					seenExts[oidStr] = true
+					cert.Extensions = append(cert.Extensions, ext)
+				}
+				err = processExtensions(cert)
+				if err != nil {
+					return nil, err
+				}
+			}
+		}
+	}
+
+	var signature asn1.BitString
+	if !input.ReadASN1BitString(&signature) {
+		return nil, errors.New("x509: malformed signature")
+	}
+	cert.Signature = signature.RightAlign()
+
+	return cert, nil
+}
+
+// ParseCertificate parses a single certificate from the given ASN.1 DER data.
+func ParseCertificate(der []byte) (*Certificate, error) {
+	cert, err := parseCertificate(der)
+	if err != nil {
+		return nil, err
+	}
+	if len(der) != len(cert.Raw) {
+		return nil, errors.New("x509: trailing data")
+	}
+	return cert, err
+}
+
+// ParseCertificates parses one or more certificates from the given ASN.1 DER
+// data. The certificates must be concatenated with no intermediate padding.
+func ParseCertificates(der []byte) ([]*Certificate, error) {
+	var certs []*Certificate
+	for len(der) > 0 {
+		cert, err := parseCertificate(der)
+		if err != nil {
+			return nil, err
+		}
+		certs = append(certs, cert)
+		der = der[len(cert.Raw):]
+	}
+	return certs, nil
+}
+
+// The X.509 standards confusingly 1-indexed the version names, but 0-indexed
+// the actual encoded version, so the version for X.509v2 is 1.
+const x509v2Version = 1
+
+// ParseRevocationList parses a X509 v2 Certificate Revocation List from the given
+// ASN.1 DER data.
+func ParseRevocationList(der []byte) (*RevocationList, error) {
+	rl := &RevocationList{}
+
+	input := cryptobyte.String(der)
+	// we read the SEQUENCE including length and tag bytes so that
+	// we can populate RevocationList.Raw, before unwrapping the
+	// SEQUENCE so it can be operated on
+	if !input.ReadASN1Element(&input, cryptobyte_asn1.SEQUENCE) {
+		return nil, errors.New("x509: malformed crl")
+	}
+	rl.Raw = input
+	if !input.ReadASN1(&input, cryptobyte_asn1.SEQUENCE) {
+		return nil, errors.New("x509: malformed crl")
+	}
+
+	var tbs cryptobyte.String
+	// do the same trick again as above to extract the raw
+	// bytes for Certificate.RawTBSCertificate
+	if !input.ReadASN1Element(&tbs, cryptobyte_asn1.SEQUENCE) {
+		return nil, errors.New("x509: malformed tbs crl")
+	}
+	rl.RawTBSRevocationList = tbs
+	if !tbs.ReadASN1(&tbs, cryptobyte_asn1.SEQUENCE) {
+		return nil, errors.New("x509: malformed tbs crl")
+	}
+
+	var version int
+	if !tbs.PeekASN1Tag(cryptobyte_asn1.INTEGER) {
+		return nil, errors.New("x509: unsupported crl version")
+	}
+	if !tbs.ReadASN1Integer(&version) {
+		return nil, errors.New("x509: malformed crl")
+	}
+	if version != x509v2Version {
+		return nil, fmt.Errorf("x509: unsupported crl version: %d", version)
+	}
+
+	var sigAISeq cryptobyte.String
+	if !tbs.ReadASN1(&sigAISeq, cryptobyte_asn1.SEQUENCE) {
+		return nil, errors.New("x509: malformed signature algorithm identifier")
+	}
+	// Before parsing the inner algorithm identifier, extract
+	// the outer algorithm identifier and make sure that they
+	// match.
+	var outerSigAISeq cryptobyte.String
+	if !input.ReadASN1(&outerSigAISeq, cryptobyte_asn1.SEQUENCE) {
+		return nil, errors.New("x509: malformed algorithm identifier")
+	}
+	if !bytes.Equal(outerSigAISeq, sigAISeq) {
+		return nil, errors.New("x509: inner and outer signature algorithm identifiers don't match")
+	}
+	sigAI, err := parseAI(sigAISeq)
+	if err != nil {
+		return nil, err
+	}
+	rl.SignatureAlgorithm = getSignatureAlgorithmFromAI(sigAI)
+
+	var signature asn1.BitString
+	if !input.ReadASN1BitString(&signature) {
+		return nil, errors.New("x509: malformed signature")
+	}
+	rl.Signature = signature.RightAlign()
+
+	var issuerSeq cryptobyte.String
+	if !tbs.ReadASN1Element(&issuerSeq, cryptobyte_asn1.SEQUENCE) {
+		return nil, errors.New("x509: malformed issuer")
+	}
+	rl.RawIssuer = issuerSeq
+	issuerRDNs, err := parseName(issuerSeq)
+	if err != nil {
+		return nil, err
+	}
+	rl.Issuer.FillFromRDNSequence(issuerRDNs)
+
+	rl.ThisUpdate, err = parseTime(&tbs)
+	if err != nil {
+		return nil, err
+	}
+	if tbs.PeekASN1Tag(cryptobyte_asn1.GeneralizedTime) || tbs.PeekASN1Tag(cryptobyte_asn1.UTCTime) {
+		rl.NextUpdate, err = parseTime(&tbs)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	if tbs.PeekASN1Tag(cryptobyte_asn1.SEQUENCE) {
+		var revokedSeq cryptobyte.String
+		if !tbs.ReadASN1(&revokedSeq, cryptobyte_asn1.SEQUENCE) {
+			return nil, errors.New("x509: malformed crl")
+		}
+		for !revokedSeq.Empty() {
+			var certSeq cryptobyte.String
+			if !revokedSeq.ReadASN1(&certSeq, cryptobyte_asn1.SEQUENCE) {
+				return nil, errors.New("x509: malformed crl")
+			}
+			rc := pkix.RevokedCertificate{}
+			rc.SerialNumber = new(big.Int)
+			if !certSeq.ReadASN1Integer(rc.SerialNumber) {
+				return nil, errors.New("x509: malformed serial number")
+			}
+			rc.RevocationTime, err = parseTime(&certSeq)
+			if err != nil {
+				return nil, err
+			}
+			var extensions cryptobyte.String
+			var present bool
+			if !certSeq.ReadOptionalASN1(&extensions, &present, cryptobyte_asn1.SEQUENCE) {
+				return nil, errors.New("x509: malformed extensions")
+			}
+			if present {
+				for !extensions.Empty() {
+					var extension cryptobyte.String
+					if !extensions.ReadASN1(&extension, cryptobyte_asn1.SEQUENCE) {
+						return nil, errors.New("x509: malformed extension")
+					}
+					ext, err := parseExtension(extension)
+					if err != nil {
+						return nil, err
+					}
+					rc.Extensions = append(rc.Extensions, ext)
+				}
+			}
+
+			rl.RevokedCertificates = append(rl.RevokedCertificates, rc)
+		}
+	}
+
+	var extensions cryptobyte.String
+	var present bool
+	if !tbs.ReadOptionalASN1(&extensions, &present, cryptobyte_asn1.Tag(0).Constructed().ContextSpecific()) {
+		return nil, errors.New("x509: malformed extensions")
+	}
+	if present {
+		if !extensions.ReadASN1(&extensions, cryptobyte_asn1.SEQUENCE) {
+			return nil, errors.New("x509: malformed extensions")
+		}
+		for !extensions.Empty() {
+			var extension cryptobyte.String
+			if !extensions.ReadASN1(&extension, cryptobyte_asn1.SEQUENCE) {
+				return nil, errors.New("x509: malformed extension")
+			}
+			ext, err := parseExtension(extension)
+			if err != nil {
+				return nil, err
+			}
+			if ext.Id.Equal(oidExtensionAuthorityKeyId) {
+				rl.AuthorityKeyId = ext.Value
+			} else if ext.Id.Equal(oidExtensionCRLNumber) {
+				value := cryptobyte.String(ext.Value)
+				rl.Number = new(big.Int)
+				if !value.ReadASN1Integer(rl.Number) {
+					return nil, errors.New("x509: malformed crl number")
+				}
+			}
+			rl.Extensions = append(rl.Extensions, ext)
+		}
+	}
+
+	return rl, nil
+}
diff --git a/contrib/go/_std_1.18/src/crypto/x509/pem_decrypt.go b/contrib/go/_std_1.19/src/crypto/x509/pem_decrypt.go
index 682923ac53..682923ac53 100644
--- a/contrib/go/_std_1.18/src/crypto/x509/pem_decrypt.go
+++ b/contrib/go/_std_1.19/src/crypto/x509/pem_decrypt.go
diff --git a/contrib/go/_std_1.18/src/crypto/x509/pkcs1.go b/contrib/go/_std_1.19/src/crypto/x509/pkcs1.go
index f9d384018a..f9d384018a 100644
--- a/contrib/go/_std_1.18/src/crypto/x509/pkcs1.go
+++ b/contrib/go/_std_1.19/src/crypto/x509/pkcs1.go
diff --git a/contrib/go/_std_1.18/src/crypto/x509/pkcs8.go b/contrib/go/_std_1.19/src/crypto/x509/pkcs8.go
index d77efa3156..d77efa3156 100644
--- a/contrib/go/_std_1.18/src/crypto/x509/pkcs8.go
+++ b/contrib/go/_std_1.19/src/crypto/x509/pkcs8.go
diff --git a/contrib/go/_std_1.19/src/crypto/x509/pkix/pkix.go b/contrib/go/_std_1.19/src/crypto/x509/pkix/pkix.go
new file mode 100644
index 0000000000..22a50eef39
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/x509/pkix/pkix.go
@@ -0,0 +1,320 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package pkix contains shared, low level structures used for ASN.1 parsing
+// and serialization of X.509 certificates, CRL and OCSP.
+package pkix
+
+import (
+	"encoding/asn1"
+	"encoding/hex"
+	"fmt"
+	"math/big"
+	"time"
+)
+
+// AlgorithmIdentifier represents the ASN.1 structure of the same name. See RFC
+// 5280, section 4.1.1.2.
+type AlgorithmIdentifier struct {
+	Algorithm  asn1.ObjectIdentifier
+	Parameters asn1.RawValue `asn1:"optional"`
+}
+
+type RDNSequence []RelativeDistinguishedNameSET
+
+var attributeTypeNames = map[string]string{
+	"2.5.4.6":  "C",
+	"2.5.4.10": "O",
+	"2.5.4.11": "OU",
+	"2.5.4.3":  "CN",
+	"2.5.4.5":  "SERIALNUMBER",
+	"2.5.4.7":  "L",
+	"2.5.4.8":  "ST",
+	"2.5.4.9":  "STREET",
+	"2.5.4.17": "POSTALCODE",
+}
+
+// String returns a string representation of the sequence r,
+// roughly following the RFC 2253 Distinguished Names syntax.
+func (r RDNSequence) String() string {
+	s := ""
+	for i := 0; i < len(r); i++ {
+		rdn := r[len(r)-1-i]
+		if i > 0 {
+			s += ","
+		}
+		for j, tv := range rdn {
+			if j > 0 {
+				s += "+"
+			}
+
+			oidString := tv.Type.String()
+			typeName, ok := attributeTypeNames[oidString]
+			if !ok {
+				derBytes, err := asn1.Marshal(tv.Value)
+				if err == nil {
+					s += oidString + "=#" + hex.EncodeToString(derBytes)
+					continue // No value escaping necessary.
+				}
+
+				typeName = oidString
+			}
+
+			valueString := fmt.Sprint(tv.Value)
+			escaped := make([]rune, 0, len(valueString))
+
+			for k, c := range valueString {
+				escape := false
+
+				switch c {
+				case ',', '+', '"', '\\', '<', '>', ';':
+					escape = true
+
+				case ' ':
+					escape = k == 0 || k == len(valueString)-1
+
+				case '#':
+					escape = k == 0
+				}
+
+				if escape {
+					escaped = append(escaped, '\\', c)
+				} else {
+					escaped = append(escaped, c)
+				}
+			}
+
+			s += typeName + "=" + string(escaped)
+		}
+	}
+
+	return s
+}
+
+type RelativeDistinguishedNameSET []AttributeTypeAndValue
+
+// AttributeTypeAndValue mirrors the ASN.1 structure of the same name in
+// RFC 5280, Section 4.1.2.4.
+type AttributeTypeAndValue struct {
+	Type  asn1.ObjectIdentifier
+	Value any
+}
+
+// AttributeTypeAndValueSET represents a set of ASN.1 sequences of
+// AttributeTypeAndValue sequences from RFC 2986 (PKCS #10).
+type AttributeTypeAndValueSET struct {
+	Type  asn1.ObjectIdentifier
+	Value [][]AttributeTypeAndValue `asn1:"set"`
+}
+
+// Extension represents the ASN.1 structure of the same name. See RFC
+// 5280, section 4.2.
+type Extension struct {
+	Id       asn1.ObjectIdentifier
+	Critical bool `asn1:"optional"`
+	Value    []byte
+}
+
+// Name represents an X.509 distinguished name. This only includes the common
+// elements of a DN. Note that Name is only an approximation of the X.509
+// structure. If an accurate representation is needed, asn1.Unmarshal the raw
+// subject or issuer as an RDNSequence.
+type Name struct {
+	Country, Organization, OrganizationalUnit []string
+	Locality, Province                        []string
+	StreetAddress, PostalCode                 []string
+	SerialNumber, CommonName                  string
+
+	// Names contains all parsed attributes. When parsing distinguished names,
+	// this can be used to extract non-standard attributes that are not parsed
+	// by this package. When marshaling to RDNSequences, the Names field is
+	// ignored, see ExtraNames.
+	Names []AttributeTypeAndValue
+
+	// ExtraNames contains attributes to be copied, raw, into any marshaled
+	// distinguished names. Values override any attributes with the same OID.
+	// The ExtraNames field is not populated when parsing, see Names.
+	ExtraNames []AttributeTypeAndValue
+}
+
+// FillFromRDNSequence populates n from the provided RDNSequence.
+// Multi-entry RDNs are flattened, all entries are added to the
+// relevant n fields, and the grouping is not preserved.
+func (n *Name) FillFromRDNSequence(rdns *RDNSequence) {
+	for _, rdn := range *rdns {
+		if len(rdn) == 0 {
+			continue
+		}
+
+		for _, atv := range rdn {
+			n.Names = append(n.Names, atv)
+			value, ok := atv.Value.(string)
+			if !ok {
+				continue
+			}
+
+			t := atv.Type
+			if len(t) == 4 && t[0] == 2 && t[1] == 5 && t[2] == 4 {
+				switch t[3] {
+				case 3:
+					n.CommonName = value
+				case 5:
+					n.SerialNumber = value
+				case 6:
+					n.Country = append(n.Country, value)
+				case 7:
+					n.Locality = append(n.Locality, value)
+				case 8:
+					n.Province = append(n.Province, value)
+				case 9:
+					n.StreetAddress = append(n.StreetAddress, value)
+				case 10:
+					n.Organization = append(n.Organization, value)
+				case 11:
+					n.OrganizationalUnit = append(n.OrganizationalUnit, value)
+				case 17:
+					n.PostalCode = append(n.PostalCode, value)
+				}
+			}
+		}
+	}
+}
+
+var (
+	oidCountry            = []int{2, 5, 4, 6}
+	oidOrganization       = []int{2, 5, 4, 10}
+	oidOrganizationalUnit = []int{2, 5, 4, 11}
+	oidCommonName         = []int{2, 5, 4, 3}
+	oidSerialNumber       = []int{2, 5, 4, 5}
+	oidLocality           = []int{2, 5, 4, 7}
+	oidProvince           = []int{2, 5, 4, 8}
+	oidStreetAddress      = []int{2, 5, 4, 9}
+	oidPostalCode         = []int{2, 5, 4, 17}
+)
+
+// appendRDNs appends a relativeDistinguishedNameSET to the given RDNSequence
+// and returns the new value. The relativeDistinguishedNameSET contains an
+// attributeTypeAndValue for each of the given values. See RFC 5280, A.1, and
+// search for AttributeTypeAndValue.
+func (n Name) appendRDNs(in RDNSequence, values []string, oid asn1.ObjectIdentifier) RDNSequence {
+	if len(values) == 0 || oidInAttributeTypeAndValue(oid, n.ExtraNames) {
+		return in
+	}
+
+	s := make([]AttributeTypeAndValue, len(values))
+	for i, value := range values {
+		s[i].Type = oid
+		s[i].Value = value
+	}
+
+	return append(in, s)
+}
+
+// ToRDNSequence converts n into a single RDNSequence. The following
+// attributes are encoded as multi-value RDNs:
+//
+//   - Country
+//   - Organization
+//   - OrganizationalUnit
+//   - Locality
+//   - Province
+//   - StreetAddress
+//   - PostalCode
+//
+// Each ExtraNames entry is encoded as an individual RDN.
+func (n Name) ToRDNSequence() (ret RDNSequence) {
+	ret = n.appendRDNs(ret, n.Country, oidCountry)
+	ret = n.appendRDNs(ret, n.Province, oidProvince)
+	ret = n.appendRDNs(ret, n.Locality, oidLocality)
+	ret = n.appendRDNs(ret, n.StreetAddress, oidStreetAddress)
+	ret = n.appendRDNs(ret, n.PostalCode, oidPostalCode)
+	ret = n.appendRDNs(ret, n.Organization, oidOrganization)
+	ret = n.appendRDNs(ret, n.OrganizationalUnit, oidOrganizationalUnit)
+	if len(n.CommonName) > 0 {
+		ret = n.appendRDNs(ret, []string{n.CommonName}, oidCommonName)
+	}
+	if len(n.SerialNumber) > 0 {
+		ret = n.appendRDNs(ret, []string{n.SerialNumber}, oidSerialNumber)
+	}
+	for _, atv := range n.ExtraNames {
+		ret = append(ret, []AttributeTypeAndValue{atv})
+	}
+
+	return ret
+}
+
+// String returns the string form of n, roughly following
+// the RFC 2253 Distinguished Names syntax.
+func (n Name) String() string {
+	var rdns RDNSequence
+	// If there are no ExtraNames, surface the parsed value (all entries in
+	// Names) instead.
+	if n.ExtraNames == nil {
+		for _, atv := range n.Names {
+			t := atv.Type
+			if len(t) == 4 && t[0] == 2 && t[1] == 5 && t[2] == 4 {
+				switch t[3] {
+				case 3, 5, 6, 7, 8, 9, 10, 11, 17:
+					// These attributes were already parsed into named fields.
+					continue
+				}
+			}
+			// Place non-standard parsed values at the beginning of the sequence
+			// so they will be at the end of the string. See Issue 39924.
+			rdns = append(rdns, []AttributeTypeAndValue{atv})
+		}
+	}
+	rdns = append(rdns, n.ToRDNSequence()...)
+	return rdns.String()
+}
+
+// oidInAttributeTypeAndValue reports whether a type with the given OID exists
+// in atv.
+func oidInAttributeTypeAndValue(oid asn1.ObjectIdentifier, atv []AttributeTypeAndValue) bool {
+	for _, a := range atv {
+		if a.Type.Equal(oid) {
+			return true
+		}
+	}
+	return false
+}
+
+// CertificateList represents the ASN.1 structure of the same name. See RFC
+// 5280, section 5.1. Use Certificate.CheckCRLSignature to verify the
+// signature.
+//
+// Deprecated: x509.RevocationList should be used instead.
+type CertificateList struct {
+	TBSCertList        TBSCertificateList
+	SignatureAlgorithm AlgorithmIdentifier
+	SignatureValue     asn1.BitString
+}
+
+// HasExpired reports whether certList should have been updated by now.
+func (certList *CertificateList) HasExpired(now time.Time) bool {
+	return !now.Before(certList.TBSCertList.NextUpdate)
+}
+
+// TBSCertificateList represents the ASN.1 structure of the same name. See RFC
+// 5280, section 5.1.
+//
+// Deprecated: x509.RevocationList should be used instead.
+type TBSCertificateList struct {
+	Raw                 asn1.RawContent
+	Version             int `asn1:"optional,default:0"`
+	Signature           AlgorithmIdentifier
+	Issuer              RDNSequence
+	ThisUpdate          time.Time
+	NextUpdate          time.Time            `asn1:"optional"`
+	RevokedCertificates []RevokedCertificate `asn1:"optional"`
+	Extensions          []Extension          `asn1:"tag:0,optional,explicit"`
+}
+
+// RevokedCertificate represents the ASN.1 structure of the same name. See RFC
+// 5280, section 5.1.
+type RevokedCertificate struct {
+	SerialNumber   *big.Int
+	RevocationTime time.Time
+	Extensions     []Extension `asn1:"optional"`
+}
diff --git a/contrib/go/_std_1.19/src/crypto/x509/root.go b/contrib/go/_std_1.19/src/crypto/x509/root.go
new file mode 100644
index 0000000000..91f4d29a1f
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/x509/root.go
@@ -0,0 +1,32 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package x509
+
+// To update the embedded iOS root store, update the -version
+// argument to the latest security_certificates version from
+// https://opensource.apple.com/source/security_certificates/
+// and run "go generate". See https://golang.org/issue/38843.
+//
+//go:generate go run root_ios_gen.go -version 55188.120.1.0.1
+
+import "sync"
+
+var (
+	once           sync.Once
+	systemRoots    *CertPool
+	systemRootsErr error
+)
+
+func systemRootsPool() *CertPool {
+	once.Do(initSystemRoots)
+	return systemRoots
+}
+
+func initSystemRoots() {
+	systemRoots, systemRootsErr = loadSystemRoots()
+	if systemRootsErr != nil {
+		systemRoots = nil
+	}
+}
diff --git a/contrib/go/_std_1.19/src/crypto/x509/root_darwin.go b/contrib/go/_std_1.19/src/crypto/x509/root_darwin.go
new file mode 100644
index 0000000000..4759462653
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/x509/root_darwin.go
@@ -0,0 +1,113 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package x509
+
+import (
+	macOS "crypto/x509/internal/macos"
+	"errors"
+)
+
+func (c *Certificate) systemVerify(opts *VerifyOptions) (chains [][]*Certificate, err error) {
+	certs := macOS.CFArrayCreateMutable()
+	defer macOS.ReleaseCFArray(certs)
+	leaf, err := macOS.SecCertificateCreateWithData(c.Raw)
+	if err != nil {
+		return nil, errors.New("invalid leaf certificate")
+	}
+	macOS.CFArrayAppendValue(certs, leaf)
+	if opts.Intermediates != nil {
+		for _, lc := range opts.Intermediates.lazyCerts {
+			c, err := lc.getCert()
+			if err != nil {
+				return nil, err
+			}
+			sc, err := macOS.SecCertificateCreateWithData(c.Raw)
+			if err == nil {
+				macOS.CFArrayAppendValue(certs, sc)
+			}
+		}
+	}
+
+	policies := macOS.CFArrayCreateMutable()
+	defer macOS.ReleaseCFArray(policies)
+	sslPolicy := macOS.SecPolicyCreateSSL(opts.DNSName)
+	macOS.CFArrayAppendValue(policies, sslPolicy)
+
+	trustObj, err := macOS.SecTrustCreateWithCertificates(certs, policies)
+	if err != nil {
+		return nil, err
+	}
+	defer macOS.CFRelease(trustObj)
+
+	if !opts.CurrentTime.IsZero() {
+		dateRef := macOS.TimeToCFDateRef(opts.CurrentTime)
+		defer macOS.CFRelease(dateRef)
+		if err := macOS.SecTrustSetVerifyDate(trustObj, dateRef); err != nil {
+			return nil, err
+		}
+	}
+
+	// TODO(roland): we may want to allow passing in SCTs via VerifyOptions and
+	// set them via SecTrustSetSignedCertificateTimestamps, since Apple will
+	// always enforce its SCT requirements, and there are still _some_ people
+	// using TLS or OCSP for that.
+
+	if err := macOS.SecTrustEvaluateWithError(trustObj); err != nil {
+		return nil, err
+	}
+
+	chain := [][]*Certificate{{}}
+	numCerts := macOS.SecTrustGetCertificateCount(trustObj)
+	for i := 0; i < numCerts; i++ {
+		certRef := macOS.SecTrustGetCertificateAtIndex(trustObj, i)
+		cert, err := exportCertificate(certRef)
+		if err != nil {
+			return nil, err
+		}
+		chain[0] = append(chain[0], cert)
+	}
+	if len(chain[0]) == 0 {
+		// This should _never_ happen, but to be safe
+		return nil, errors.New("x509: macOS certificate verification internal error")
+	}
+
+	if opts.DNSName != "" {
+		// If we have a DNS name, apply our own name verification
+		if err := chain[0][0].VerifyHostname(opts.DNSName); err != nil {
+			return nil, err
+		}
+	}
+
+	keyUsages := opts.KeyUsages
+	if len(keyUsages) == 0 {
+		keyUsages = []ExtKeyUsage{ExtKeyUsageServerAuth}
+	}
+
+	// If any key usage is acceptable then we're done.
+	for _, usage := range keyUsages {
+		if usage == ExtKeyUsageAny {
+			return chain, nil
+		}
+	}
+
+	if !checkChainForKeyUsage(chain[0], keyUsages) {
+		return nil, CertificateInvalidError{c, IncompatibleUsage, ""}
+	}
+
+	return chain, nil
+}
+
+// exportCertificate returns a *Certificate for a SecCertificateRef.
+func exportCertificate(cert macOS.CFRef) (*Certificate, error) {
+	data, err := macOS.SecCertificateCopyData(cert)
+	if err != nil {
+		return nil, err
+	}
+	return ParseCertificate(data)
+}
+
+func loadSystemRoots() (*CertPool, error) {
+	return &CertPool{systemPool: true}, nil
+}
diff --git a/contrib/go/_std_1.18/src/crypto/x509/root_linux.go b/contrib/go/_std_1.19/src/crypto/x509/root_linux.go
index e32989b999..e32989b999 100644
--- a/contrib/go/_std_1.18/src/crypto/x509/root_linux.go
+++ b/contrib/go/_std_1.19/src/crypto/x509/root_linux.go
diff --git a/contrib/go/_std_1.18/src/crypto/x509/root_unix.go b/contrib/go/_std_1.19/src/crypto/x509/root_unix.go
index aa54f891ca..aa54f891ca 100644
--- a/contrib/go/_std_1.18/src/crypto/x509/root_unix.go
+++ b/contrib/go/_std_1.19/src/crypto/x509/root_unix.go
diff --git a/contrib/go/_std_1.19/src/crypto/x509/sec1.go b/contrib/go/_std_1.19/src/crypto/x509/sec1.go
new file mode 100644
index 0000000000..ff48e0cc9e
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/x509/sec1.go
@@ -0,0 +1,125 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package x509
+
+import (
+	"crypto/ecdsa"
+	"crypto/elliptic"
+	"encoding/asn1"
+	"errors"
+	"fmt"
+	"math/big"
+)
+
+const ecPrivKeyVersion = 1
+
+// ecPrivateKey reflects an ASN.1 Elliptic Curve Private Key Structure.
+// References:
+//
+//	RFC 5915
+//	SEC1 - http://www.secg.org/sec1-v2.pdf
+//
+// Per RFC 5915 the NamedCurveOID is marked as ASN.1 OPTIONAL, however in
+// most cases it is not.
+type ecPrivateKey struct {
+	Version       int
+	PrivateKey    []byte
+	NamedCurveOID asn1.ObjectIdentifier `asn1:"optional,explicit,tag:0"`
+	PublicKey     asn1.BitString        `asn1:"optional,explicit,tag:1"`
+}
+
+// ParseECPrivateKey parses an EC private key in SEC 1, ASN.1 DER form.
+//
+// This kind of key is commonly encoded in PEM blocks of type "EC PRIVATE KEY".
+func ParseECPrivateKey(der []byte) (*ecdsa.PrivateKey, error) {
+	return parseECPrivateKey(nil, der)
+}
+
+// MarshalECPrivateKey converts an EC private key to SEC 1, ASN.1 DER form.
+//
+// This kind of key is commonly encoded in PEM blocks of type "EC PRIVATE KEY".
+// For a more flexible key format which is not EC specific, use
+// MarshalPKCS8PrivateKey.
+func MarshalECPrivateKey(key *ecdsa.PrivateKey) ([]byte, error) {
+	oid, ok := oidFromNamedCurve(key.Curve)
+	if !ok {
+		return nil, errors.New("x509: unknown elliptic curve")
+	}
+
+	return marshalECPrivateKeyWithOID(key, oid)
+}
+
+// marshalECPrivateKey marshals an EC private key into ASN.1, DER format and
+// sets the curve ID to the given OID, or omits it if OID is nil.
+func marshalECPrivateKeyWithOID(key *ecdsa.PrivateKey, oid asn1.ObjectIdentifier) ([]byte, error) {
+	if !key.Curve.IsOnCurve(key.X, key.Y) {
+		return nil, errors.New("invalid elliptic key public key")
+	}
+	privateKey := make([]byte, (key.Curve.Params().N.BitLen()+7)/8)
+	return asn1.Marshal(ecPrivateKey{
+		Version:       1,
+		PrivateKey:    key.D.FillBytes(privateKey),
+		NamedCurveOID: oid,
+		PublicKey:     asn1.BitString{Bytes: elliptic.Marshal(key.Curve, key.X, key.Y)},
+	})
+}
+
+// parseECPrivateKey parses an ASN.1 Elliptic Curve Private Key Structure.
+// The OID for the named curve may be provided from another source (such as
+// the PKCS8 container) - if it is provided then use this instead of the OID
+// that may exist in the EC private key structure.
+func parseECPrivateKey(namedCurveOID *asn1.ObjectIdentifier, der []byte) (key *ecdsa.PrivateKey, err error) {
+	var privKey ecPrivateKey
+	if _, err := asn1.Unmarshal(der, &privKey); err != nil {
+		if _, err := asn1.Unmarshal(der, &pkcs8{}); err == nil {
+			return nil, errors.New("x509: failed to parse private key (use ParsePKCS8PrivateKey instead for this key format)")
+		}
+		if _, err := asn1.Unmarshal(der, &pkcs1PrivateKey{}); err == nil {
+			return nil, errors.New("x509: failed to parse private key (use ParsePKCS1PrivateKey instead for this key format)")
+		}
+		return nil, errors.New("x509: failed to parse EC private key: " + err.Error())
+	}
+	if privKey.Version != ecPrivKeyVersion {
+		return nil, fmt.Errorf("x509: unknown EC private key version %d", privKey.Version)
+	}
+
+	var curve elliptic.Curve
+	if namedCurveOID != nil {
+		curve = namedCurveFromOID(*namedCurveOID)
+	} else {
+		curve = namedCurveFromOID(privKey.NamedCurveOID)
+	}
+	if curve == nil {
+		return nil, errors.New("x509: unknown elliptic curve")
+	}
+
+	k := new(big.Int).SetBytes(privKey.PrivateKey)
+	curveOrder := curve.Params().N
+	if k.Cmp(curveOrder) >= 0 {
+		return nil, errors.New("x509: invalid elliptic curve private key value")
+	}
+	priv := new(ecdsa.PrivateKey)
+	priv.Curve = curve
+	priv.D = k
+
+	privateKey := make([]byte, (curveOrder.BitLen()+7)/8)
+
+	// Some private keys have leading zero padding. This is invalid
+	// according to [SEC1], but this code will ignore it.
+	for len(privKey.PrivateKey) > len(privateKey) {
+		if privKey.PrivateKey[0] != 0 {
+			return nil, errors.New("x509: invalid private key length")
+		}
+		privKey.PrivateKey = privKey.PrivateKey[1:]
+	}
+
+	// Some private keys remove all leading zeros, this is also invalid
+	// according to [SEC1] but since OpenSSL used to do this, we ignore
+	// this too.
+	copy(privateKey[len(privateKey)-len(privKey.PrivateKey):], privKey.PrivateKey)
+	priv.X, priv.Y = curve.ScalarBaseMult(privateKey)
+
+	return priv, nil
+}
diff --git a/contrib/go/_std_1.19/src/crypto/x509/verify.go b/contrib/go/_std_1.19/src/crypto/x509/verify.go
new file mode 100644
index 0000000000..c49335d225
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/x509/verify.go
@@ -0,0 +1,1170 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package x509
+
+import (
+	"bytes"
+	"crypto"
+	"crypto/x509/pkix"
+	"errors"
+	"fmt"
+	"net"
+	"net/url"
+	"reflect"
+	"runtime"
+	"strings"
+	"time"
+	"unicode/utf8"
+)
+
+type InvalidReason int
+
+const (
+	// NotAuthorizedToSign results when a certificate is signed by another
+	// which isn't marked as a CA certificate.
+	NotAuthorizedToSign InvalidReason = iota
+	// Expired results when a certificate has expired, based on the time
+	// given in the VerifyOptions.
+	Expired
+	// CANotAuthorizedForThisName results when an intermediate or root
+	// certificate has a name constraint which doesn't permit a DNS or
+	// other name (including IP address) in the leaf certificate.
+	CANotAuthorizedForThisName
+	// TooManyIntermediates results when a path length constraint is
+	// violated.
+	TooManyIntermediates
+	// IncompatibleUsage results when the certificate's key usage indicates
+	// that it may only be used for a different purpose.
+	IncompatibleUsage
+	// NameMismatch results when the subject name of a parent certificate
+	// does not match the issuer name in the child.
+	NameMismatch
+	// NameConstraintsWithoutSANs is a legacy error and is no longer returned.
+	NameConstraintsWithoutSANs
+	// UnconstrainedName results when a CA certificate contains permitted
+	// name constraints, but leaf certificate contains a name of an
+	// unsupported or unconstrained type.
+	UnconstrainedName
+	// TooManyConstraints results when the number of comparison operations
+	// needed to check a certificate exceeds the limit set by
+	// VerifyOptions.MaxConstraintComparisions. This limit exists to
+	// prevent pathological certificates can consuming excessive amounts of
+	// CPU time to verify.
+	TooManyConstraints
+	// CANotAuthorizedForExtKeyUsage results when an intermediate or root
+	// certificate does not permit a requested extended key usage.
+	CANotAuthorizedForExtKeyUsage
+)
+
+// CertificateInvalidError results when an odd error occurs. Users of this
+// library probably want to handle all these errors uniformly.
+type CertificateInvalidError struct {
+	Cert   *Certificate
+	Reason InvalidReason
+	Detail string
+}
+
+func (e CertificateInvalidError) Error() string {
+	switch e.Reason {
+	case NotAuthorizedToSign:
+		return "x509: certificate is not authorized to sign other certificates"
+	case Expired:
+		return "x509: certificate has expired or is not yet valid: " + e.Detail
+	case CANotAuthorizedForThisName:
+		return "x509: a root or intermediate certificate is not authorized to sign for this name: " + e.Detail
+	case CANotAuthorizedForExtKeyUsage:
+		return "x509: a root or intermediate certificate is not authorized for an extended key usage: " + e.Detail
+	case TooManyIntermediates:
+		return "x509: too many intermediates for path length constraint"
+	case IncompatibleUsage:
+		return "x509: certificate specifies an incompatible key usage"
+	case NameMismatch:
+		return "x509: issuer name does not match subject from issuing certificate"
+	case NameConstraintsWithoutSANs:
+		return "x509: issuer has name constraints but leaf doesn't have a SAN extension"
+	case UnconstrainedName:
+		return "x509: issuer has name constraints but leaf contains unknown or unconstrained name: " + e.Detail
+	}
+	return "x509: unknown error"
+}
+
+// HostnameError results when the set of authorized names doesn't match the
+// requested name.
+type HostnameError struct {
+	Certificate *Certificate
+	Host        string
+}
+
+func (h HostnameError) Error() string {
+	c := h.Certificate
+
+	if !c.hasSANExtension() && matchHostnames(c.Subject.CommonName, h.Host) {
+		return "x509: certificate relies on legacy Common Name field, use SANs instead"
+	}
+
+	var valid string
+	if ip := net.ParseIP(h.Host); ip != nil {
+		// Trying to validate an IP
+		if len(c.IPAddresses) == 0 {
+			return "x509: cannot validate certificate for " + h.Host + " because it doesn't contain any IP SANs"
+		}
+		for _, san := range c.IPAddresses {
+			if len(valid) > 0 {
+				valid += ", "
+			}
+			valid += san.String()
+		}
+	} else {
+		valid = strings.Join(c.DNSNames, ", ")
+	}
+
+	if len(valid) == 0 {
+		return "x509: certificate is not valid for any names, but wanted to match " + h.Host
+	}
+	return "x509: certificate is valid for " + valid + ", not " + h.Host
+}
+
+// UnknownAuthorityError results when the certificate issuer is unknown
+type UnknownAuthorityError struct {
+	Cert *Certificate
+	// hintErr contains an error that may be helpful in determining why an
+	// authority wasn't found.
+	hintErr error
+	// hintCert contains a possible authority certificate that was rejected
+	// because of the error in hintErr.
+	hintCert *Certificate
+}
+
+func (e UnknownAuthorityError) Error() string {
+	s := "x509: certificate signed by unknown authority"
+	if e.hintErr != nil {
+		certName := e.hintCert.Subject.CommonName
+		if len(certName) == 0 {
+			if len(e.hintCert.Subject.Organization) > 0 {
+				certName = e.hintCert.Subject.Organization[0]
+			} else {
+				certName = "serial:" + e.hintCert.SerialNumber.String()
+			}
+		}
+		s += fmt.Sprintf(" (possibly because of %q while trying to verify candidate authority certificate %q)", e.hintErr, certName)
+	}
+	return s
+}
+
+// SystemRootsError results when we fail to load the system root certificates.
+type SystemRootsError struct {
+	Err error
+}
+
+func (se SystemRootsError) Error() string {
+	msg := "x509: failed to load system roots and no roots provided"
+	if se.Err != nil {
+		return msg + "; " + se.Err.Error()
+	}
+	return msg
+}
+
+func (se SystemRootsError) Unwrap() error { return se.Err }
+
+// errNotParsed is returned when a certificate without ASN.1 contents is
+// verified. Platform-specific verification needs the ASN.1 contents.
+var errNotParsed = errors.New("x509: missing ASN.1 contents; use ParseCertificate")
+
+// VerifyOptions contains parameters for Certificate.Verify.
+type VerifyOptions struct {
+	// DNSName, if set, is checked against the leaf certificate with
+	// Certificate.VerifyHostname or the platform verifier.
+	DNSName string
+
+	// Intermediates is an optional pool of certificates that are not trust
+	// anchors, but can be used to form a chain from the leaf certificate to a
+	// root certificate.
+	Intermediates *CertPool
+	// Roots is the set of trusted root certificates the leaf certificate needs
+	// to chain up to. If nil, the system roots or the platform verifier are used.
+	Roots *CertPool
+
+	// CurrentTime is used to check the validity of all certificates in the
+	// chain. If zero, the current time is used.
+	CurrentTime time.Time
+
+	// KeyUsages specifies which Extended Key Usage values are acceptable. A
+	// chain is accepted if it allows any of the listed values. An empty list
+	// means ExtKeyUsageServerAuth. To accept any key usage, include ExtKeyUsageAny.
+	KeyUsages []ExtKeyUsage
+
+	// MaxConstraintComparisions is the maximum number of comparisons to
+	// perform when checking a given certificate's name constraints. If
+	// zero, a sensible default is used. This limit prevents pathological
+	// certificates from consuming excessive amounts of CPU time when
+	// validating. It does not apply to the platform verifier.
+	MaxConstraintComparisions int
+}
+
+const (
+	leafCertificate = iota
+	intermediateCertificate
+	rootCertificate
+)
+
+// rfc2821Mailbox represents a “mailbox” (which is an email address to most
+// people) by breaking it into the “local” (i.e. before the '@') and “domain”
+// parts.
+type rfc2821Mailbox struct {
+	local, domain string
+}
+
+// parseRFC2821Mailbox parses an email address into local and domain parts,
+// based on the ABNF for a “Mailbox” from RFC 2821. According to RFC 5280,
+// Section 4.2.1.6 that's correct for an rfc822Name from a certificate: “The
+// format of an rfc822Name is a "Mailbox" as defined in RFC 2821, Section 4.1.2”.
+func parseRFC2821Mailbox(in string) (mailbox rfc2821Mailbox, ok bool) {
+	if len(in) == 0 {
+		return mailbox, false
+	}
+
+	localPartBytes := make([]byte, 0, len(in)/2)
+
+	if in[0] == '"' {
+		// Quoted-string = DQUOTE *qcontent DQUOTE
+		// non-whitespace-control = %d1-8 / %d11 / %d12 / %d14-31 / %d127
+		// qcontent = qtext / quoted-pair
+		// qtext = non-whitespace-control /
+		//         %d33 / %d35-91 / %d93-126
+		// quoted-pair = ("\" text) / obs-qp
+		// text = %d1-9 / %d11 / %d12 / %d14-127 / obs-text
+		//
+		// (Names beginning with “obs-” are the obsolete syntax from RFC 2822,
+		// Section 4. Since it has been 16 years, we no longer accept that.)
+		in = in[1:]
+	QuotedString:
+		for {
+			if len(in) == 0 {
+				return mailbox, false
+			}
+			c := in[0]
+			in = in[1:]
+
+			switch {
+			case c == '"':
+				break QuotedString
+
+			case c == '\\':
+				// quoted-pair
+				if len(in) == 0 {
+					return mailbox, false
+				}
+				if in[0] == 11 ||
+					in[0] == 12 ||
+					(1 <= in[0] && in[0] <= 9) ||
+					(14 <= in[0] && in[0] <= 127) {
+					localPartBytes = append(localPartBytes, in[0])
+					in = in[1:]
+				} else {
+					return mailbox, false
+				}
+
+			case c == 11 ||
+				c == 12 ||
+				// Space (char 32) is not allowed based on the
+				// BNF, but RFC 3696 gives an example that
+				// assumes that it is. Several “verified”
+				// errata continue to argue about this point.
+				// We choose to accept it.
+				c == 32 ||
+				c == 33 ||
+				c == 127 ||
+				(1 <= c && c <= 8) ||
+				(14 <= c && c <= 31) ||
+				(35 <= c && c <= 91) ||
+				(93 <= c && c <= 126):
+				// qtext
+				localPartBytes = append(localPartBytes, c)
+
+			default:
+				return mailbox, false
+			}
+		}
+	} else {
+		// Atom ("." Atom)*
+	NextChar:
+		for len(in) > 0 {
+			// atext from RFC 2822, Section 3.2.4
+			c := in[0]
+
+			switch {
+			case c == '\\':
+				// Examples given in RFC 3696 suggest that
+				// escaped characters can appear outside of a
+				// quoted string. Several “verified” errata
+				// continue to argue the point. We choose to
+				// accept it.
+				in = in[1:]
+				if len(in) == 0 {
+					return mailbox, false
+				}
+				fallthrough
+
+			case ('0' <= c && c <= '9') ||
+				('a' <= c && c <= 'z') ||
+				('A' <= c && c <= 'Z') ||
+				c == '!' || c == '#' || c == '$' || c == '%' ||
+				c == '&' || c == '\'' || c == '*' || c == '+' ||
+				c == '-' || c == '/' || c == '=' || c == '?' ||
+				c == '^' || c == '_' || c == '`' || c == '{' ||
+				c == '|' || c == '}' || c == '~' || c == '.':
+				localPartBytes = append(localPartBytes, in[0])
+				in = in[1:]
+
+			default:
+				break NextChar
+			}
+		}
+
+		if len(localPartBytes) == 0 {
+			return mailbox, false
+		}
+
+		// From RFC 3696, Section 3:
+		// “period (".") may also appear, but may not be used to start
+		// or end the local part, nor may two or more consecutive
+		// periods appear.”
+		twoDots := []byte{'.', '.'}
+		if localPartBytes[0] == '.' ||
+			localPartBytes[len(localPartBytes)-1] == '.' ||
+			bytes.Contains(localPartBytes, twoDots) {
+			return mailbox, false
+		}
+	}
+
+	if len(in) == 0 || in[0] != '@' {
+		return mailbox, false
+	}
+	in = in[1:]
+
+	// The RFC species a format for domains, but that's known to be
+	// violated in practice so we accept that anything after an '@' is the
+	// domain part.
+	if _, ok := domainToReverseLabels(in); !ok {
+		return mailbox, false
+	}
+
+	mailbox.local = string(localPartBytes)
+	mailbox.domain = in
+	return mailbox, true
+}
+
+// domainToReverseLabels converts a textual domain name like foo.example.com to
+// the list of labels in reverse order, e.g. ["com", "example", "foo"].
+func domainToReverseLabels(domain string) (reverseLabels []string, ok bool) {
+	for len(domain) > 0 {
+		if i := strings.LastIndexByte(domain, '.'); i == -1 {
+			reverseLabels = append(reverseLabels, domain)
+			domain = ""
+		} else {
+			reverseLabels = append(reverseLabels, domain[i+1:])
+			domain = domain[:i]
+		}
+	}
+
+	if len(reverseLabels) > 0 && len(reverseLabels[0]) == 0 {
+		// An empty label at the end indicates an absolute value.
+		return nil, false
+	}
+
+	for _, label := range reverseLabels {
+		if len(label) == 0 {
+			// Empty labels are otherwise invalid.
+			return nil, false
+		}
+
+		for _, c := range label {
+			if c < 33 || c > 126 {
+				// Invalid character.
+				return nil, false
+			}
+		}
+	}
+
+	return reverseLabels, true
+}
+
+func matchEmailConstraint(mailbox rfc2821Mailbox, constraint string) (bool, error) {
+	// If the constraint contains an @, then it specifies an exact mailbox
+	// name.
+	if strings.Contains(constraint, "@") {
+		constraintMailbox, ok := parseRFC2821Mailbox(constraint)
+		if !ok {
+			return false, fmt.Errorf("x509: internal error: cannot parse constraint %q", constraint)
+		}
+		return mailbox.local == constraintMailbox.local && strings.EqualFold(mailbox.domain, constraintMailbox.domain), nil
+	}
+
+	// Otherwise the constraint is like a DNS constraint of the domain part
+	// of the mailbox.
+	return matchDomainConstraint(mailbox.domain, constraint)
+}
+
+func matchURIConstraint(uri *url.URL, constraint string) (bool, error) {
+	// From RFC 5280, Section 4.2.1.10:
+	// “a uniformResourceIdentifier that does not include an authority
+	// component with a host name specified as a fully qualified domain
+	// name (e.g., if the URI either does not include an authority
+	// component or includes an authority component in which the host name
+	// is specified as an IP address), then the application MUST reject the
+	// certificate.”
+
+	host := uri.Host
+	if len(host) == 0 {
+		return false, fmt.Errorf("URI with empty host (%q) cannot be matched against constraints", uri.String())
+	}
+
+	if strings.Contains(host, ":") && !strings.HasSuffix(host, "]") {
+		var err error
+		host, _, err = net.SplitHostPort(uri.Host)
+		if err != nil {
+			return false, err
+		}
+	}
+
+	if strings.HasPrefix(host, "[") && strings.HasSuffix(host, "]") ||
+		net.ParseIP(host) != nil {
+		return false, fmt.Errorf("URI with IP (%q) cannot be matched against constraints", uri.String())
+	}
+
+	return matchDomainConstraint(host, constraint)
+}
+
+func matchIPConstraint(ip net.IP, constraint *net.IPNet) (bool, error) {
+	if len(ip) != len(constraint.IP) {
+		return false, nil
+	}
+
+	for i := range ip {
+		if mask := constraint.Mask[i]; ip[i]&mask != constraint.IP[i]&mask {
+			return false, nil
+		}
+	}
+
+	return true, nil
+}
+
+func matchDomainConstraint(domain, constraint string) (bool, error) {
+	// The meaning of zero length constraints is not specified, but this
+	// code follows NSS and accepts them as matching everything.
+	if len(constraint) == 0 {
+		return true, nil
+	}
+
+	domainLabels, ok := domainToReverseLabels(domain)
+	if !ok {
+		return false, fmt.Errorf("x509: internal error: cannot parse domain %q", domain)
+	}
+
+	// RFC 5280 says that a leading period in a domain name means that at
+	// least one label must be prepended, but only for URI and email
+	// constraints, not DNS constraints. The code also supports that
+	// behaviour for DNS constraints.
+
+	mustHaveSubdomains := false
+	if constraint[0] == '.' {
+		mustHaveSubdomains = true
+		constraint = constraint[1:]
+	}
+
+	constraintLabels, ok := domainToReverseLabels(constraint)
+	if !ok {
+		return false, fmt.Errorf("x509: internal error: cannot parse domain %q", constraint)
+	}
+
+	if len(domainLabels) < len(constraintLabels) ||
+		(mustHaveSubdomains && len(domainLabels) == len(constraintLabels)) {
+		return false, nil
+	}
+
+	for i, constraintLabel := range constraintLabels {
+		if !strings.EqualFold(constraintLabel, domainLabels[i]) {
+			return false, nil
+		}
+	}
+
+	return true, nil
+}
+
+// checkNameConstraints checks that c permits a child certificate to claim the
+// given name, of type nameType. The argument parsedName contains the parsed
+// form of name, suitable for passing to the match function. The total number
+// of comparisons is tracked in the given count and should not exceed the given
+// limit.
+func (c *Certificate) checkNameConstraints(count *int,
+	maxConstraintComparisons int,
+	nameType string,
+	name string,
+	parsedName any,
+	match func(parsedName, constraint any) (match bool, err error),
+	permitted, excluded any) error {
+
+	excludedValue := reflect.ValueOf(excluded)
+
+	*count += excludedValue.Len()
+	if *count > maxConstraintComparisons {
+		return CertificateInvalidError{c, TooManyConstraints, ""}
+	}
+
+	for i := 0; i < excludedValue.Len(); i++ {
+		constraint := excludedValue.Index(i).Interface()
+		match, err := match(parsedName, constraint)
+		if err != nil {
+			return CertificateInvalidError{c, CANotAuthorizedForThisName, err.Error()}
+		}
+
+		if match {
+			return CertificateInvalidError{c, CANotAuthorizedForThisName, fmt.Sprintf("%s %q is excluded by constraint %q", nameType, name, constraint)}
+		}
+	}
+
+	permittedValue := reflect.ValueOf(permitted)
+
+	*count += permittedValue.Len()
+	if *count > maxConstraintComparisons {
+		return CertificateInvalidError{c, TooManyConstraints, ""}
+	}
+
+	ok := true
+	for i := 0; i < permittedValue.Len(); i++ {
+		constraint := permittedValue.Index(i).Interface()
+
+		var err error
+		if ok, err = match(parsedName, constraint); err != nil {
+			return CertificateInvalidError{c, CANotAuthorizedForThisName, err.Error()}
+		}
+
+		if ok {
+			break
+		}
+	}
+
+	if !ok {
+		return CertificateInvalidError{c, CANotAuthorizedForThisName, fmt.Sprintf("%s %q is not permitted by any constraint", nameType, name)}
+	}
+
+	return nil
+}
+
+// isValid performs validity checks on c given that it is a candidate to append
+// to the chain in currentChain.
+func (c *Certificate) isValid(certType int, currentChain []*Certificate, opts *VerifyOptions) error {
+	if len(c.UnhandledCriticalExtensions) > 0 {
+		return UnhandledCriticalExtension{}
+	}
+
+	if len(currentChain) > 0 {
+		child := currentChain[len(currentChain)-1]
+		if !bytes.Equal(child.RawIssuer, c.RawSubject) {
+			return CertificateInvalidError{c, NameMismatch, ""}
+		}
+	}
+
+	now := opts.CurrentTime
+	if now.IsZero() {
+		now = time.Now()
+	}
+	if now.Before(c.NotBefore) {
+		return CertificateInvalidError{
+			Cert:   c,
+			Reason: Expired,
+			Detail: fmt.Sprintf("current time %s is before %s", now.Format(time.RFC3339), c.NotBefore.Format(time.RFC3339)),
+		}
+	} else if now.After(c.NotAfter) {
+		return CertificateInvalidError{
+			Cert:   c,
+			Reason: Expired,
+			Detail: fmt.Sprintf("current time %s is after %s", now.Format(time.RFC3339), c.NotAfter.Format(time.RFC3339)),
+		}
+	}
+
+	maxConstraintComparisons := opts.MaxConstraintComparisions
+	if maxConstraintComparisons == 0 {
+		maxConstraintComparisons = 250000
+	}
+	comparisonCount := 0
+
+	var leaf *Certificate
+	if certType == intermediateCertificate || certType == rootCertificate {
+		if len(currentChain) == 0 {
+			return errors.New("x509: internal error: empty chain when appending CA cert")
+		}
+		leaf = currentChain[0]
+	}
+
+	if (certType == intermediateCertificate || certType == rootCertificate) &&
+		c.hasNameConstraints() {
+		toCheck := []*Certificate{}
+		if leaf.hasSANExtension() {
+			toCheck = append(toCheck, leaf)
+		}
+		if c.hasSANExtension() {
+			toCheck = append(toCheck, c)
+		}
+		for _, sanCert := range toCheck {
+			err := forEachSAN(sanCert.getSANExtension(), func(tag int, data []byte) error {
+				switch tag {
+				case nameTypeEmail:
+					name := string(data)
+					mailbox, ok := parseRFC2821Mailbox(name)
+					if !ok {
+						return fmt.Errorf("x509: cannot parse rfc822Name %q", mailbox)
+					}
+
+					if err := c.checkNameConstraints(&comparisonCount, maxConstraintComparisons, "email address", name, mailbox,
+						func(parsedName, constraint any) (bool, error) {
+							return matchEmailConstraint(parsedName.(rfc2821Mailbox), constraint.(string))
+						}, c.PermittedEmailAddresses, c.ExcludedEmailAddresses); err != nil {
+						return err
+					}
+
+				case nameTypeDNS:
+					name := string(data)
+					if _, ok := domainToReverseLabels(name); !ok {
+						return fmt.Errorf("x509: cannot parse dnsName %q", name)
+					}
+
+					if err := c.checkNameConstraints(&comparisonCount, maxConstraintComparisons, "DNS name", name, name,
+						func(parsedName, constraint any) (bool, error) {
+							return matchDomainConstraint(parsedName.(string), constraint.(string))
+						}, c.PermittedDNSDomains, c.ExcludedDNSDomains); err != nil {
+						return err
+					}
+
+				case nameTypeURI:
+					name := string(data)
+					uri, err := url.Parse(name)
+					if err != nil {
+						return fmt.Errorf("x509: internal error: URI SAN %q failed to parse", name)
+					}
+
+					if err := c.checkNameConstraints(&comparisonCount, maxConstraintComparisons, "URI", name, uri,
+						func(parsedName, constraint any) (bool, error) {
+							return matchURIConstraint(parsedName.(*url.URL), constraint.(string))
+						}, c.PermittedURIDomains, c.ExcludedURIDomains); err != nil {
+						return err
+					}
+
+				case nameTypeIP:
+					ip := net.IP(data)
+					if l := len(ip); l != net.IPv4len && l != net.IPv6len {
+						return fmt.Errorf("x509: internal error: IP SAN %x failed to parse", data)
+					}
+
+					if err := c.checkNameConstraints(&comparisonCount, maxConstraintComparisons, "IP address", ip.String(), ip,
+						func(parsedName, constraint any) (bool, error) {
+							return matchIPConstraint(parsedName.(net.IP), constraint.(*net.IPNet))
+						}, c.PermittedIPRanges, c.ExcludedIPRanges); err != nil {
+						return err
+					}
+
+				default:
+					// Unknown SAN types are ignored.
+				}
+
+				return nil
+			})
+
+			if err != nil {
+				return err
+			}
+		}
+	}
+
+	// KeyUsage status flags are ignored. From Engineering Security, Peter
+	// Gutmann: A European government CA marked its signing certificates as
+	// being valid for encryption only, but no-one noticed. Another
+	// European CA marked its signature keys as not being valid for
+	// signatures. A different CA marked its own trusted root certificate
+	// as being invalid for certificate signing. Another national CA
+	// distributed a certificate to be used to encrypt data for the
+	// country’s tax authority that was marked as only being usable for
+	// digital signatures but not for encryption. Yet another CA reversed
+	// the order of the bit flags in the keyUsage due to confusion over
+	// encoding endianness, essentially setting a random keyUsage in
+	// certificates that it issued. Another CA created a self-invalidating
+	// certificate by adding a certificate policy statement stipulating
+	// that the certificate had to be used strictly as specified in the
+	// keyUsage, and a keyUsage containing a flag indicating that the RSA
+	// encryption key could only be used for Diffie-Hellman key agreement.
+
+	if certType == intermediateCertificate && (!c.BasicConstraintsValid || !c.IsCA) {
+		return CertificateInvalidError{c, NotAuthorizedToSign, ""}
+	}
+
+	if c.BasicConstraintsValid && c.MaxPathLen >= 0 {
+		numIntermediates := len(currentChain) - 1
+		if numIntermediates > c.MaxPathLen {
+			return CertificateInvalidError{c, TooManyIntermediates, ""}
+		}
+	}
+
+	if !boringAllowCert(c) {
+		// IncompatibleUsage is not quite right here,
+		// but it's also the "no chains found" error
+		// and is close enough.
+		return CertificateInvalidError{c, IncompatibleUsage, ""}
+	}
+
+	return nil
+}
+
+// Verify attempts to verify c by building one or more chains from c to a
+// certificate in opts.Roots, using certificates in opts.Intermediates if
+// needed. If successful, it returns one or more chains where the first
+// element of the chain is c and the last element is from opts.Roots.
+//
+// If opts.Roots is nil, the platform verifier might be used, and
+// verification details might differ from what is described below. If system
+// roots are unavailable the returned error will be of type SystemRootsError.
+//
+// Name constraints in the intermediates will be applied to all names claimed
+// in the chain, not just opts.DNSName. Thus it is invalid for a leaf to claim
+// example.com if an intermediate doesn't permit it, even if example.com is not
+// the name being validated. Note that DirectoryName constraints are not
+// supported.
+//
+// Name constraint validation follows the rules from RFC 5280, with the
+// addition that DNS name constraints may use the leading period format
+// defined for emails and URIs. When a constraint has a leading period
+// it indicates that at least one additional label must be prepended to
+// the constrained name to be considered valid.
+//
+// Extended Key Usage values are enforced nested down a chain, so an intermediate
+// or root that enumerates EKUs prevents a leaf from asserting an EKU not in that
+// list. (While this is not specified, it is common practice in order to limit
+// the types of certificates a CA can issue.)
+//
+// Certificates that use SHA1WithRSA and ECDSAWithSHA1 signatures are not supported,
+// and will not be used to build chains.
+//
+// WARNING: this function doesn't do any revocation checking.
+func (c *Certificate) Verify(opts VerifyOptions) (chains [][]*Certificate, err error) {
+	// Platform-specific verification needs the ASN.1 contents so
+	// this makes the behavior consistent across platforms.
+	if len(c.Raw) == 0 {
+		return nil, errNotParsed
+	}
+	for i := 0; i < opts.Intermediates.len(); i++ {
+		c, err := opts.Intermediates.cert(i)
+		if err != nil {
+			return nil, fmt.Errorf("crypto/x509: error fetching intermediate: %w", err)
+		}
+		if len(c.Raw) == 0 {
+			return nil, errNotParsed
+		}
+	}
+
+	// Use platform verifiers, where available, if Roots is from SystemCertPool.
+	if runtime.GOOS == "windows" || runtime.GOOS == "darwin" || runtime.GOOS == "ios" {
+		if opts.Roots == nil {
+			return c.systemVerify(&opts)
+		}
+		if opts.Roots != nil && opts.Roots.systemPool {
+			platformChains, err := c.systemVerify(&opts)
+			// If the platform verifier succeeded, or there are no additional
+			// roots, return the platform verifier result. Otherwise, continue
+			// with the Go verifier.
+			if err == nil || opts.Roots.len() == 0 {
+				return platformChains, err
+			}
+		}
+	}
+
+	if opts.Roots == nil {
+		opts.Roots = systemRootsPool()
+		if opts.Roots == nil {
+			return nil, SystemRootsError{systemRootsErr}
+		}
+	}
+
+	err = c.isValid(leafCertificate, nil, &opts)
+	if err != nil {
+		return
+	}
+
+	if len(opts.DNSName) > 0 {
+		err = c.VerifyHostname(opts.DNSName)
+		if err != nil {
+			return
+		}
+	}
+
+	var candidateChains [][]*Certificate
+	if opts.Roots.contains(c) {
+		candidateChains = [][]*Certificate{{c}}
+	} else {
+		candidateChains, err = c.buildChains([]*Certificate{c}, nil, &opts)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	if len(opts.KeyUsages) == 0 {
+		opts.KeyUsages = []ExtKeyUsage{ExtKeyUsageServerAuth}
+	}
+
+	for _, eku := range opts.KeyUsages {
+		if eku == ExtKeyUsageAny {
+			// If any key usage is acceptable, no need to check the chain for
+			// key usages.
+			return candidateChains, nil
+		}
+	}
+
+	chains = make([][]*Certificate, 0, len(candidateChains))
+	for _, candidate := range candidateChains {
+		if checkChainForKeyUsage(candidate, opts.KeyUsages) {
+			chains = append(chains, candidate)
+		}
+	}
+
+	if len(chains) == 0 {
+		return nil, CertificateInvalidError{c, IncompatibleUsage, ""}
+	}
+
+	return chains, nil
+}
+
+func appendToFreshChain(chain []*Certificate, cert *Certificate) []*Certificate {
+	n := make([]*Certificate, len(chain)+1)
+	copy(n, chain)
+	n[len(chain)] = cert
+	return n
+}
+
+// alreadyInChain checks whether a candidate certificate is present in a chain.
+// Rather than doing a direct byte for byte equivalency check, we check if the
+// subject, public key, and SAN, if present, are equal. This prevents loops that
+// are created by mutual cross-signatures, or other cross-signature bridge
+// oddities.
+func alreadyInChain(candidate *Certificate, chain []*Certificate) bool {
+	type pubKeyEqual interface {
+		Equal(crypto.PublicKey) bool
+	}
+
+	var candidateSAN *pkix.Extension
+	for _, ext := range candidate.Extensions {
+		if ext.Id.Equal(oidExtensionSubjectAltName) {
+			candidateSAN = &ext
+			break
+		}
+	}
+
+	for _, cert := range chain {
+		if !bytes.Equal(candidate.RawSubject, cert.RawSubject) {
+			continue
+		}
+		if !candidate.PublicKey.(pubKeyEqual).Equal(cert.PublicKey) {
+			continue
+		}
+		var certSAN *pkix.Extension
+		for _, ext := range cert.Extensions {
+			if ext.Id.Equal(oidExtensionSubjectAltName) {
+				certSAN = &ext
+				break
+			}
+		}
+		if candidateSAN == nil && certSAN == nil {
+			return true
+		} else if candidateSAN == nil || certSAN == nil {
+			return false
+		}
+		if bytes.Equal(candidateSAN.Value, certSAN.Value) {
+			return true
+		}
+	}
+	return false
+}
+
+// maxChainSignatureChecks is the maximum number of CheckSignatureFrom calls
+// that an invocation of buildChains will (transitively) make. Most chains are
+// less than 15 certificates long, so this leaves space for multiple chains and
+// for failed checks due to different intermediates having the same Subject.
+const maxChainSignatureChecks = 100
+
+func (c *Certificate) buildChains(currentChain []*Certificate, sigChecks *int, opts *VerifyOptions) (chains [][]*Certificate, err error) {
+	var (
+		hintErr  error
+		hintCert *Certificate
+	)
+
+	considerCandidate := func(certType int, candidate *Certificate) {
+		if alreadyInChain(candidate, currentChain) {
+			return
+		}
+
+		if sigChecks == nil {
+			sigChecks = new(int)
+		}
+		*sigChecks++
+		if *sigChecks > maxChainSignatureChecks {
+			err = errors.New("x509: signature check attempts limit reached while verifying certificate chain")
+			return
+		}
+
+		if err := c.CheckSignatureFrom(candidate); err != nil {
+			if hintErr == nil {
+				hintErr = err
+				hintCert = candidate
+			}
+			return
+		}
+
+		err = candidate.isValid(certType, currentChain, opts)
+		if err != nil {
+			return
+		}
+
+		switch certType {
+		case rootCertificate:
+			chains = append(chains, appendToFreshChain(currentChain, candidate))
+		case intermediateCertificate:
+			var childChains [][]*Certificate
+			childChains, err = candidate.buildChains(appendToFreshChain(currentChain, candidate), sigChecks, opts)
+			chains = append(chains, childChains...)
+		}
+	}
+
+	for _, root := range opts.Roots.findPotentialParents(c) {
+		considerCandidate(rootCertificate, root)
+	}
+	for _, intermediate := range opts.Intermediates.findPotentialParents(c) {
+		considerCandidate(intermediateCertificate, intermediate)
+	}
+
+	if len(chains) > 0 {
+		err = nil
+	}
+	if len(chains) == 0 && err == nil {
+		err = UnknownAuthorityError{c, hintErr, hintCert}
+	}
+
+	return
+}
+
+func validHostnamePattern(host string) bool { return validHostname(host, true) }
+func validHostnameInput(host string) bool   { return validHostname(host, false) }
+
+// validHostname reports whether host is a valid hostname that can be matched or
+// matched against according to RFC 6125 2.2, with some leniency to accommodate
+// legacy values.
+func validHostname(host string, isPattern bool) bool {
+	if !isPattern {
+		host = strings.TrimSuffix(host, ".")
+	}
+	if len(host) == 0 {
+		return false
+	}
+
+	for i, part := range strings.Split(host, ".") {
+		if part == "" {
+			// Empty label.
+			return false
+		}
+		if isPattern && i == 0 && part == "*" {
+			// Only allow full left-most wildcards, as those are the only ones
+			// we match, and matching literal '*' characters is probably never
+			// the expected behavior.
+			continue
+		}
+		for j, c := range part {
+			if 'a' <= c && c <= 'z' {
+				continue
+			}
+			if '0' <= c && c <= '9' {
+				continue
+			}
+			if 'A' <= c && c <= 'Z' {
+				continue
+			}
+			if c == '-' && j != 0 {
+				continue
+			}
+			if c == '_' {
+				// Not a valid character in hostnames, but commonly
+				// found in deployments outside the WebPKI.
+				continue
+			}
+			return false
+		}
+	}
+
+	return true
+}
+
+func matchExactly(hostA, hostB string) bool {
+	if hostA == "" || hostA == "." || hostB == "" || hostB == "." {
+		return false
+	}
+	return toLowerCaseASCII(hostA) == toLowerCaseASCII(hostB)
+}
+
+func matchHostnames(pattern, host string) bool {
+	pattern = toLowerCaseASCII(pattern)
+	host = toLowerCaseASCII(strings.TrimSuffix(host, "."))
+
+	if len(pattern) == 0 || len(host) == 0 {
+		return false
+	}
+
+	patternParts := strings.Split(pattern, ".")
+	hostParts := strings.Split(host, ".")
+
+	if len(patternParts) != len(hostParts) {
+		return false
+	}
+
+	for i, patternPart := range patternParts {
+		if i == 0 && patternPart == "*" {
+			continue
+		}
+		if patternPart != hostParts[i] {
+			return false
+		}
+	}
+
+	return true
+}
+
+// toLowerCaseASCII returns a lower-case version of in. See RFC 6125 6.4.1. We use
+// an explicitly ASCII function to avoid any sharp corners resulting from
+// performing Unicode operations on DNS labels.
+func toLowerCaseASCII(in string) string {
+	// If the string is already lower-case then there's nothing to do.
+	isAlreadyLowerCase := true
+	for _, c := range in {
+		if c == utf8.RuneError {
+			// If we get a UTF-8 error then there might be
+			// upper-case ASCII bytes in the invalid sequence.
+			isAlreadyLowerCase = false
+			break
+		}
+		if 'A' <= c && c <= 'Z' {
+			isAlreadyLowerCase = false
+			break
+		}
+	}
+
+	if isAlreadyLowerCase {
+		return in
+	}
+
+	out := []byte(in)
+	for i, c := range out {
+		if 'A' <= c && c <= 'Z' {
+			out[i] += 'a' - 'A'
+		}
+	}
+	return string(out)
+}
+
+// VerifyHostname returns nil if c is a valid certificate for the named host.
+// Otherwise it returns an error describing the mismatch.
+//
+// IP addresses can be optionally enclosed in square brackets and are checked
+// against the IPAddresses field. Other names are checked case insensitively
+// against the DNSNames field. If the names are valid hostnames, the certificate
+// fields can have a wildcard as the left-most label.
+//
+// Note that the legacy Common Name field is ignored.
+func (c *Certificate) VerifyHostname(h string) error {
+	// IP addresses may be written in [ ].
+	candidateIP := h
+	if len(h) >= 3 && h[0] == '[' && h[len(h)-1] == ']' {
+		candidateIP = h[1 : len(h)-1]
+	}
+	if ip := net.ParseIP(candidateIP); ip != nil {
+		// We only match IP addresses against IP SANs.
+		// See RFC 6125, Appendix B.2.
+		for _, candidate := range c.IPAddresses {
+			if ip.Equal(candidate) {
+				return nil
+			}
+		}
+		return HostnameError{c, candidateIP}
+	}
+
+	candidateName := toLowerCaseASCII(h) // Save allocations inside the loop.
+	validCandidateName := validHostnameInput(candidateName)
+
+	for _, match := range c.DNSNames {
+		// Ideally, we'd only match valid hostnames according to RFC 6125 like
+		// browsers (more or less) do, but in practice Go is used in a wider
+		// array of contexts and can't even assume DNS resolution. Instead,
+		// always allow perfect matches, and only apply wildcard and trailing
+		// dot processing to valid hostnames.
+		if validCandidateName && validHostnamePattern(match) {
+			if matchHostnames(match, candidateName) {
+				return nil
+			}
+		} else {
+			if matchExactly(match, candidateName) {
+				return nil
+			}
+		}
+	}
+
+	return HostnameError{c, h}
+}
+
+func checkChainForKeyUsage(chain []*Certificate, keyUsages []ExtKeyUsage) bool {
+	usages := make([]ExtKeyUsage, len(keyUsages))
+	copy(usages, keyUsages)
+
+	if len(chain) == 0 {
+		return false
+	}
+
+	usagesRemaining := len(usages)
+
+	// We walk down the list and cross out any usages that aren't supported
+	// by each certificate. If we cross out all the usages, then the chain
+	// is unacceptable.
+
+NextCert:
+	for i := len(chain) - 1; i >= 0; i-- {
+		cert := chain[i]
+		if len(cert.ExtKeyUsage) == 0 && len(cert.UnknownExtKeyUsage) == 0 {
+			// The certificate doesn't have any extended key usage specified.
+			continue
+		}
+
+		for _, usage := range cert.ExtKeyUsage {
+			if usage == ExtKeyUsageAny {
+				// The certificate is explicitly good for any usage.
+				continue NextCert
+			}
+		}
+
+		const invalidUsage ExtKeyUsage = -1
+
+	NextRequestedUsage:
+		for i, requestedUsage := range usages {
+			if requestedUsage == invalidUsage {
+				continue
+			}
+
+			for _, usage := range cert.ExtKeyUsage {
+				if requestedUsage == usage {
+					continue NextRequestedUsage
+				}
+			}
+
+			usages[i] = invalidUsage
+			usagesRemaining--
+			if usagesRemaining == 0 {
+				return false
+			}
+		}
+	}
+
+	return true
+}
diff --git a/contrib/go/_std_1.19/src/crypto/x509/x509.go b/contrib/go/_std_1.19/src/crypto/x509/x509.go
new file mode 100644
index 0000000000..7c64761bd7
--- /dev/null
+++ b/contrib/go/_std_1.19/src/crypto/x509/x509.go
@@ -0,0 +1,2284 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package x509 parses X.509-encoded keys and certificates.
+package x509
+
+import (
+	"bytes"
+	"crypto"
+	"crypto/ecdsa"
+	"crypto/ed25519"
+	"crypto/elliptic"
+	"crypto/rsa"
+	"crypto/sha1"
+	"crypto/x509/pkix"
+	"encoding/asn1"
+	"encoding/pem"
+	"errors"
+	"fmt"
+	"internal/godebug"
+	"io"
+	"math/big"
+	"net"
+	"net/url"
+	"strconv"
+	"time"
+	"unicode"
+
+	// Explicitly import these for their crypto.RegisterHash init side-effects.
+	// Keep these as blank imports, even if they're imported above.
+	_ "crypto/sha1"
+	_ "crypto/sha256"
+	_ "crypto/sha512"
+
+	"golang.org/x/crypto/cryptobyte"
+	cryptobyte_asn1 "golang.org/x/crypto/cryptobyte/asn1"
+)
+
+// pkixPublicKey reflects a PKIX public key structure. See SubjectPublicKeyInfo
+// in RFC 3280.
+type pkixPublicKey struct {
+	Algo      pkix.AlgorithmIdentifier
+	BitString asn1.BitString
+}
+
+// ParsePKIXPublicKey parses a public key in PKIX, ASN.1 DER form.
+// The encoded public key is a SubjectPublicKeyInfo structure
+// (see RFC 5280, Section 4.1).
+//
+// It returns a *rsa.PublicKey, *dsa.PublicKey, *ecdsa.PublicKey, or
+// ed25519.PublicKey. More types might be supported in the future.
+//
+// This kind of key is commonly encoded in PEM blocks of type "PUBLIC KEY".
+func ParsePKIXPublicKey(derBytes []byte) (pub any, err error) {
+	var pki publicKeyInfo
+	if rest, err := asn1.Unmarshal(derBytes, &pki); err != nil {
+		if _, err := asn1.Unmarshal(derBytes, &pkcs1PublicKey{}); err == nil {
+			return nil, errors.New("x509: failed to parse public key (use ParsePKCS1PublicKey instead for this key format)")
+		}
+		return nil, err
+	} else if len(rest) != 0 {
+		return nil, errors.New("x509: trailing data after ASN.1 of public-key")
+	}
+	algo := getPublicKeyAlgorithmFromOID(pki.Algorithm.Algorithm)
+	if algo == UnknownPublicKeyAlgorithm {
+		return nil, errors.New("x509: unknown public key algorithm")
+	}
+	return parsePublicKey(algo, &pki)
+}
+
+func marshalPublicKey(pub any) (publicKeyBytes []byte, publicKeyAlgorithm pkix.AlgorithmIdentifier, err error) {
+	switch pub := pub.(type) {
+	case *rsa.PublicKey:
+		publicKeyBytes, err = asn1.Marshal(pkcs1PublicKey{
+			N: pub.N,
+			E: pub.E,
+		})
+		if err != nil {
+			return nil, pkix.AlgorithmIdentifier{}, err
+		}
+		publicKeyAlgorithm.Algorithm = oidPublicKeyRSA
+		// This is a NULL parameters value which is required by
+		// RFC 3279, Section 2.3.1.
+		publicKeyAlgorithm.Parameters = asn1.NullRawValue
+	case *ecdsa.PublicKey:
+		oid, ok := oidFromNamedCurve(pub.Curve)
+		if !ok {
+			return nil, pkix.AlgorithmIdentifier{}, errors.New("x509: unsupported elliptic curve")
+		}
+		if !pub.Curve.IsOnCurve(pub.X, pub.Y) {
+			return nil, pkix.AlgorithmIdentifier{}, errors.New("x509: invalid elliptic curve public key")
+		}
+		publicKeyBytes = elliptic.Marshal(pub.Curve, pub.X, pub.Y)
+		publicKeyAlgorithm.Algorithm = oidPublicKeyECDSA
+		var paramBytes []byte
+		paramBytes, err = asn1.Marshal(oid)
+		if err != nil {
+			return
+		}
+		publicKeyAlgorithm.Parameters.FullBytes = paramBytes
+	case ed25519.PublicKey:
+		publicKeyBytes = pub
+		publicKeyAlgorithm.Algorithm = oidPublicKeyEd25519
+	default:
+		return nil, pkix.AlgorithmIdentifier{}, fmt.Errorf("x509: unsupported public key type: %T", pub)
+	}
+
+	return publicKeyBytes, publicKeyAlgorithm, nil
+}
+
+// MarshalPKIXPublicKey converts a public key to PKIX, ASN.1 DER form.
+// The encoded public key is a SubjectPublicKeyInfo structure
+// (see RFC 5280, Section 4.1).
+//
+// The following key types are currently supported: *rsa.PublicKey, *ecdsa.PublicKey
+// and ed25519.PublicKey. Unsupported key types result in an error.
+//
+// This kind of key is commonly encoded in PEM blocks of type "PUBLIC KEY".
+func MarshalPKIXPublicKey(pub any) ([]byte, error) {
+	var publicKeyBytes []byte
+	var publicKeyAlgorithm pkix.AlgorithmIdentifier
+	var err error
+
+	if publicKeyBytes, publicKeyAlgorithm, err = marshalPublicKey(pub); err != nil {
+		return nil, err
+	}
+
+	pkix := pkixPublicKey{
+		Algo: publicKeyAlgorithm,
+		BitString: asn1.BitString{
+			Bytes:     publicKeyBytes,
+			BitLength: 8 * len(publicKeyBytes),
+		},
+	}
+
+	ret, _ := asn1.Marshal(pkix)
+	return ret, nil
+}
+
+// These structures reflect the ASN.1 structure of X.509 certificates.:
+
+type certificate struct {
+	Raw                asn1.RawContent
+	TBSCertificate     tbsCertificate
+	SignatureAlgorithm pkix.AlgorithmIdentifier
+	SignatureValue     asn1.BitString
+}
+
+type tbsCertificate struct {
+	Raw                asn1.RawContent
+	Version            int `asn1:"optional,explicit,default:0,tag:0"`
+	SerialNumber       *big.Int
+	SignatureAlgorithm pkix.AlgorithmIdentifier
+	Issuer             asn1.RawValue
+	Validity           validity
+	Subject            asn1.RawValue
+	PublicKey          publicKeyInfo
+	UniqueId           asn1.BitString   `asn1:"optional,tag:1"`
+	SubjectUniqueId    asn1.BitString   `asn1:"optional,tag:2"`
+	Extensions         []pkix.Extension `asn1:"omitempty,optional,explicit,tag:3"`
+}
+
+type dsaAlgorithmParameters struct {
+	P, Q, G *big.Int
+}
+
+type validity struct {
+	NotBefore, NotAfter time.Time
+}
+
+type publicKeyInfo struct {
+	Raw       asn1.RawContent
+	Algorithm pkix.AlgorithmIdentifier
+	PublicKey asn1.BitString
+}
+
+// RFC 5280,  4.2.1.1
+type authKeyId struct {
+	Id []byte `asn1:"optional,tag:0"`
+}
+
+type SignatureAlgorithm int
+
+const (
+	UnknownSignatureAlgorithm SignatureAlgorithm = iota
+
+	MD2WithRSA  // Unsupported.
+	MD5WithRSA  // Only supported for signing, not verification.
+	SHA1WithRSA // Only supported for signing, and verification of CRLs, CSRs, and OCSP responses.
+	SHA256WithRSA
+	SHA384WithRSA
+	SHA512WithRSA
+	DSAWithSHA1   // Unsupported.
+	DSAWithSHA256 // Unsupported.
+	ECDSAWithSHA1 // Only supported for signing, and verification of CRLs, CSRs, and OCSP responses.
+	ECDSAWithSHA256
+	ECDSAWithSHA384
+	ECDSAWithSHA512
+	SHA256WithRSAPSS
+	SHA384WithRSAPSS
+	SHA512WithRSAPSS
+	PureEd25519
+)
+
+func (algo SignatureAlgorithm) isRSAPSS() bool {
+	switch algo {
+	case SHA256WithRSAPSS, SHA384WithRSAPSS, SHA512WithRSAPSS:
+		return true
+	default:
+		return false
+	}
+}
+
+func (algo SignatureAlgorithm) String() string {
+	for _, details := range signatureAlgorithmDetails {
+		if details.algo == algo {
+			return details.name
+		}
+	}
+	return strconv.Itoa(int(algo))
+}
+
+type PublicKeyAlgorithm int
+
+const (
+	UnknownPublicKeyAlgorithm PublicKeyAlgorithm = iota
+	RSA
+	DSA // Unsupported.
+	ECDSA
+	Ed25519
+)
+
+var publicKeyAlgoName = [...]string{
+	RSA:     "RSA",
+	DSA:     "DSA",
+	ECDSA:   "ECDSA",
+	Ed25519: "Ed25519",
+}
+
+func (algo PublicKeyAlgorithm) String() string {
+	if 0 < algo && int(algo) < len(publicKeyAlgoName) {
+		return publicKeyAlgoName[algo]
+	}
+	return strconv.Itoa(int(algo))
+}
+
+// OIDs for signature algorithms
+//
+//	pkcs-1 OBJECT IDENTIFIER ::= {
+//		iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) 1 }
+//
+// RFC 3279 2.2.1 RSA Signature Algorithms
+//
+//	md2WithRSAEncryption OBJECT IDENTIFIER ::= { pkcs-1 2 }
+//
+//	md5WithRSAEncryption OBJECT IDENTIFIER ::= { pkcs-1 4 }
+//
+//	sha-1WithRSAEncryption OBJECT IDENTIFIER ::= { pkcs-1 5 }
+//
+//	dsaWithSha1 OBJECT IDENTIFIER ::= {
+//		iso(1) member-body(2) us(840) x9-57(10040) x9cm(4) 3 }
+//
+// RFC 3279 2.2.3 ECDSA Signature Algorithm
+//
+//	ecdsa-with-SHA1 OBJECT IDENTIFIER ::= {
+//		iso(1) member-body(2) us(840) ansi-x962(10045)
+//		signatures(4) ecdsa-with-SHA1(1)}
+//
+// RFC 4055 5 PKCS #1 Version 1.5
+//
+//	sha256WithRSAEncryption OBJECT IDENTIFIER ::= { pkcs-1 11 }
+//
+//	sha384WithRSAEncryption OBJECT IDENTIFIER ::= { pkcs-1 12 }
+//
+//	sha512WithRSAEncryption OBJECT IDENTIFIER ::= { pkcs-1 13 }
+//
+// RFC 5758 3.1 DSA Signature Algorithms
+//
+//	dsaWithSha256 OBJECT IDENTIFIER ::= {
+//		joint-iso-ccitt(2) country(16) us(840) organization(1) gov(101)
+//		csor(3) algorithms(4) id-dsa-with-sha2(3) 2}
+//
+// RFC 5758 3.2 ECDSA Signature Algorithm
+//
+//	ecdsa-with-SHA256 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
+//		us(840) ansi-X9-62(10045) signatures(4) ecdsa-with-SHA2(3) 2 }
+//
+//	ecdsa-with-SHA384 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
+//		us(840) ansi-X9-62(10045) signatures(4) ecdsa-with-SHA2(3) 3 }
+//
+//	ecdsa-with-SHA512 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
+//		us(840) ansi-X9-62(10045) signatures(4) ecdsa-with-SHA2(3) 4 }
+//
+// RFC 8410 3 Curve25519 and Curve448 Algorithm Identifiers
+//
+//	id-Ed25519   OBJECT IDENTIFIER ::= { 1 3 101 112 }
+var (
+	oidSignatureMD2WithRSA      = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 2}
+	oidSignatureMD5WithRSA      = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 4}
+	oidSignatureSHA1WithRSA     = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 5}
+	oidSignatureSHA256WithRSA   = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 11}
+	oidSignatureSHA384WithRSA   = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 12}
+	oidSignatureSHA512WithRSA   = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 13}
+	oidSignatureRSAPSS          = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 10}
+	oidSignatureDSAWithSHA1     = asn1.ObjectIdentifier{1, 2, 840, 10040, 4, 3}
+	oidSignatureDSAWithSHA256   = asn1.ObjectIdentifier{2, 16, 840, 1, 101, 3, 4, 3, 2}
+	oidSignatureECDSAWithSHA1   = asn1.ObjectIdentifier{1, 2, 840, 10045, 4, 1}
+	oidSignatureECDSAWithSHA256 = asn1.ObjectIdentifier{1, 2, 840, 10045, 4, 3, 2}
+	oidSignatureECDSAWithSHA384 = asn1.ObjectIdentifier{1, 2, 840, 10045, 4, 3, 3}
+	oidSignatureECDSAWithSHA512 = asn1.ObjectIdentifier{1, 2, 840, 10045, 4, 3, 4}
+	oidSignatureEd25519         = asn1.ObjectIdentifier{1, 3, 101, 112}
+
+	oidSHA256 = asn1.ObjectIdentifier{2, 16, 840, 1, 101, 3, 4, 2, 1}
+	oidSHA384 = asn1.ObjectIdentifier{2, 16, 840, 1, 101, 3, 4, 2, 2}
+	oidSHA512 = asn1.ObjectIdentifier{2, 16, 840, 1, 101, 3, 4, 2, 3}
+
+	oidMGF1 = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 8}
+
+	// oidISOSignatureSHA1WithRSA means the same as oidSignatureSHA1WithRSA
+	// but it's specified by ISO. Microsoft's makecert.exe has been known
+	// to produce certificates with this OID.
+	oidISOSignatureSHA1WithRSA = asn1.ObjectIdentifier{1, 3, 14, 3, 2, 29}
+)
+
+var signatureAlgorithmDetails = []struct {
+	algo       SignatureAlgorithm
+	name       string
+	oid        asn1.ObjectIdentifier
+	pubKeyAlgo PublicKeyAlgorithm
+	hash       crypto.Hash
+}{
+	{MD2WithRSA, "MD2-RSA", oidSignatureMD2WithRSA, RSA, crypto.Hash(0) /* no value for MD2 */},
+	{MD5WithRSA, "MD5-RSA", oidSignatureMD5WithRSA, RSA, crypto.MD5},
+	{SHA1WithRSA, "SHA1-RSA", oidSignatureSHA1WithRSA, RSA, crypto.SHA1},
+	{SHA1WithRSA, "SHA1-RSA", oidISOSignatureSHA1WithRSA, RSA, crypto.SHA1},
+	{SHA256WithRSA, "SHA256-RSA", oidSignatureSHA256WithRSA, RSA, crypto.SHA256},
+	{SHA384WithRSA, "SHA384-RSA", oidSignatureSHA384WithRSA, RSA, crypto.SHA384},
+	{SHA512WithRSA, "SHA512-RSA", oidSignatureSHA512WithRSA, RSA, crypto.SHA512},
+	{SHA256WithRSAPSS, "SHA256-RSAPSS", oidSignatureRSAPSS, RSA, crypto.SHA256},
+	{SHA384WithRSAPSS, "SHA384-RSAPSS", oidSignatureRSAPSS, RSA, crypto.SHA384},
+	{SHA512WithRSAPSS, "SHA512-RSAPSS", oidSignatureRSAPSS, RSA, crypto.SHA512},
+	{DSAWithSHA1, "DSA-SHA1", oidSignatureDSAWithSHA1, DSA, crypto.SHA1},
+	{DSAWithSHA256, "DSA-SHA256", oidSignatureDSAWithSHA256, DSA, crypto.SHA256},
+	{ECDSAWithSHA1, "ECDSA-SHA1", oidSignatureECDSAWithSHA1, ECDSA, crypto.SHA1},
+	{ECDSAWithSHA256, "ECDSA-SHA256", oidSignatureECDSAWithSHA256, ECDSA, crypto.SHA256},
+	{ECDSAWithSHA384, "ECDSA-SHA384", oidSignatureECDSAWithSHA384, ECDSA, crypto.SHA384},
+	{ECDSAWithSHA512, "ECDSA-SHA512", oidSignatureECDSAWithSHA512, ECDSA, crypto.SHA512},
+	{PureEd25519, "Ed25519", oidSignatureEd25519, Ed25519, crypto.Hash(0) /* no pre-hashing */},
+}
+
+// hashToPSSParameters contains the DER encoded RSA PSS parameters for the
+// SHA256, SHA384, and SHA512 hashes as defined in RFC 3447, Appendix A.2.3.
+// The parameters contain the following values:
+//   - hashAlgorithm contains the associated hash identifier with NULL parameters
+//   - maskGenAlgorithm always contains the default mgf1SHA1 identifier
+//   - saltLength contains the length of the associated hash
+//   - trailerField always contains the default trailerFieldBC value
+var hashToPSSParameters = map[crypto.Hash]asn1.RawValue{
+	crypto.SHA256: asn1.RawValue{FullBytes: []byte{48, 52, 160, 15, 48, 13, 6, 9, 96, 134, 72, 1, 101, 3, 4, 2, 1, 5, 0, 161, 28, 48, 26, 6, 9, 42, 134, 72, 134, 247, 13, 1, 1, 8, 48, 13, 6, 9, 96, 134, 72, 1, 101, 3, 4, 2, 1, 5, 0, 162, 3, 2, 1, 32}},
+	crypto.SHA384: asn1.RawValue{FullBytes: []byte{48, 52, 160, 15, 48, 13, 6, 9, 96, 134, 72, 1, 101, 3, 4, 2, 2, 5, 0, 161, 28, 48, 26, 6, 9, 42, 134, 72, 134, 247, 13, 1, 1, 8, 48, 13, 6, 9, 96, 134, 72, 1, 101, 3, 4, 2, 2, 5, 0, 162, 3, 2, 1, 48}},
+	crypto.SHA512: asn1.RawValue{FullBytes: []byte{48, 52, 160, 15, 48, 13, 6, 9, 96, 134, 72, 1, 101, 3, 4, 2, 3, 5, 0, 161, 28, 48, 26, 6, 9, 42, 134, 72, 134, 247, 13, 1, 1, 8, 48, 13, 6, 9, 96, 134, 72, 1, 101, 3, 4, 2, 3, 5, 0, 162, 3, 2, 1, 64}},
+}
+
+// pssParameters reflects the parameters in an AlgorithmIdentifier that
+// specifies RSA PSS. See RFC 3447, Appendix A.2.3.
+type pssParameters struct {
+	// The following three fields are not marked as
+	// optional because the default values specify SHA-1,
+	// which is no longer suitable for use in signatures.
+	Hash         pkix.AlgorithmIdentifier `asn1:"explicit,tag:0"`
+	MGF          pkix.AlgorithmIdentifier `asn1:"explicit,tag:1"`
+	SaltLength   int                      `asn1:"explicit,tag:2"`
+	TrailerField int                      `asn1:"optional,explicit,tag:3,default:1"`
+}
+
+func getSignatureAlgorithmFromAI(ai pkix.AlgorithmIdentifier) SignatureAlgorithm {
+	if ai.Algorithm.Equal(oidSignatureEd25519) {
+		// RFC 8410, Section 3
+		// > For all of the OIDs, the parameters MUST be absent.
+		if len(ai.Parameters.FullBytes) != 0 {
+			return UnknownSignatureAlgorithm
+		}
+	}
+
+	if !ai.Algorithm.Equal(oidSignatureRSAPSS) {
+		for _, details := range signatureAlgorithmDetails {
+			if ai.Algorithm.Equal(details.oid) {
+				return details.algo
+			}
+		}
+		return UnknownSignatureAlgorithm
+	}
+
+	// RSA PSS is special because it encodes important parameters
+	// in the Parameters.
+
+	var params pssParameters
+	if _, err := asn1.Unmarshal(ai.Parameters.FullBytes, &params); err != nil {
+		return UnknownSignatureAlgorithm
+	}
+
+	var mgf1HashFunc pkix.AlgorithmIdentifier
+	if _, err := asn1.Unmarshal(params.MGF.Parameters.FullBytes, &mgf1HashFunc); err != nil {
+		return UnknownSignatureAlgorithm
+	}
+
+	// PSS is greatly overburdened with options. This code forces them into
+	// three buckets by requiring that the MGF1 hash function always match the
+	// message hash function (as recommended in RFC 3447, Section 8.1), that the
+	// salt length matches the hash length, and that the trailer field has the
+	// default value.
+	if (len(params.Hash.Parameters.FullBytes) != 0 && !bytes.Equal(params.Hash.Parameters.FullBytes, asn1.NullBytes)) ||
+		!params.MGF.Algorithm.Equal(oidMGF1) ||
+		!mgf1HashFunc.Algorithm.Equal(params.Hash.Algorithm) ||
+		(len(mgf1HashFunc.Parameters.FullBytes) != 0 && !bytes.Equal(mgf1HashFunc.Parameters.FullBytes, asn1.NullBytes)) ||
+		params.TrailerField != 1 {
+		return UnknownSignatureAlgorithm
+	}
+
+	switch {
+	case params.Hash.Algorithm.Equal(oidSHA256) && params.SaltLength == 32:
+		return SHA256WithRSAPSS
+	case params.Hash.Algorithm.Equal(oidSHA384) && params.SaltLength == 48:
+		return SHA384WithRSAPSS
+	case params.Hash.Algorithm.Equal(oidSHA512) && params.SaltLength == 64:
+		return SHA512WithRSAPSS
+	}
+
+	return UnknownSignatureAlgorithm
+}
+
+// RFC 3279, 2.3 Public Key Algorithms
+//
+//	pkcs-1 OBJECT IDENTIFIER ::== { iso(1) member-body(2) us(840)
+//		rsadsi(113549) pkcs(1) 1 }
+//
+// rsaEncryption OBJECT IDENTIFIER ::== { pkcs1-1 1 }
+//
+//	id-dsa OBJECT IDENTIFIER ::== { iso(1) member-body(2) us(840)
+//		x9-57(10040) x9cm(4) 1 }
+//
+// RFC 5480, 2.1.1 Unrestricted Algorithm Identifier and Parameters
+//
+//	id-ecPublicKey OBJECT IDENTIFIER ::= {
+//		iso(1) member-body(2) us(840) ansi-X9-62(10045) keyType(2) 1 }
+var (
+	oidPublicKeyRSA     = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 1}
+	oidPublicKeyDSA     = asn1.ObjectIdentifier{1, 2, 840, 10040, 4, 1}
+	oidPublicKeyECDSA   = asn1.ObjectIdentifier{1, 2, 840, 10045, 2, 1}
+	oidPublicKeyEd25519 = oidSignatureEd25519
+)
+
+func getPublicKeyAlgorithmFromOID(oid asn1.ObjectIdentifier) PublicKeyAlgorithm {
+	switch {
+	case oid.Equal(oidPublicKeyRSA):
+		return RSA
+	case oid.Equal(oidPublicKeyDSA):
+		return DSA
+	case oid.Equal(oidPublicKeyECDSA):
+		return ECDSA
+	case oid.Equal(oidPublicKeyEd25519):
+		return Ed25519
+	}
+	return UnknownPublicKeyAlgorithm
+}
+
+// RFC 5480, 2.1.1.1. Named Curve
+//
+//	secp224r1 OBJECT IDENTIFIER ::= {
+//	  iso(1) identified-organization(3) certicom(132) curve(0) 33 }
+//
+//	secp256r1 OBJECT IDENTIFIER ::= {
+//	  iso(1) member-body(2) us(840) ansi-X9-62(10045) curves(3)
+//	  prime(1) 7 }
+//
+//	secp384r1 OBJECT IDENTIFIER ::= {
+//	  iso(1) identified-organization(3) certicom(132) curve(0) 34 }
+//
+//	secp521r1 OBJECT IDENTIFIER ::= {
+//	  iso(1) identified-organization(3) certicom(132) curve(0) 35 }
+//
+// NB: secp256r1 is equivalent to prime256v1
+var (
+	oidNamedCurveP224 = asn1.ObjectIdentifier{1, 3, 132, 0, 33}
+	oidNamedCurveP256 = asn1.ObjectIdentifier{1, 2, 840, 10045, 3, 1, 7}
+	oidNamedCurveP384 = asn1.ObjectIdentifier{1, 3, 132, 0, 34}
+	oidNamedCurveP521 = asn1.ObjectIdentifier{1, 3, 132, 0, 35}
+)
+
+func namedCurveFromOID(oid asn1.ObjectIdentifier) elliptic.Curve {
+	switch {
+	case oid.Equal(oidNamedCurveP224):
+		return elliptic.P224()
+	case oid.Equal(oidNamedCurveP256):
+		return elliptic.P256()
+	case oid.Equal(oidNamedCurveP384):
+		return elliptic.P384()
+	case oid.Equal(oidNamedCurveP521):
+		return elliptic.P521()
+	}
+	return nil
+}
+
+func oidFromNamedCurve(curve elliptic.Curve) (asn1.ObjectIdentifier, bool) {
+	switch curve {
+	case elliptic.P224():
+		return oidNamedCurveP224, true
+	case elliptic.P256():
+		return oidNamedCurveP256, true
+	case elliptic.P384():
+		return oidNamedCurveP384, true
+	case elliptic.P521():
+		return oidNamedCurveP521, true
+	}
+
+	return nil, false
+}
+
+// KeyUsage represents the set of actions that are valid for a given key. It's
+// a bitmap of the KeyUsage* constants.
+type KeyUsage int
+
+const (
+	KeyUsageDigitalSignature KeyUsage = 1 << iota
+	KeyUsageContentCommitment
+	KeyUsageKeyEncipherment
+	KeyUsageDataEncipherment
+	KeyUsageKeyAgreement
+	KeyUsageCertSign
+	KeyUsageCRLSign
+	KeyUsageEncipherOnly
+	KeyUsageDecipherOnly
+)
+
+// RFC 5280, 4.2.1.12  Extended Key Usage
+//
+//	anyExtendedKeyUsage OBJECT IDENTIFIER ::= { id-ce-extKeyUsage 0 }
+//
+//	id-kp OBJECT IDENTIFIER ::= { id-pkix 3 }
+//
+//	id-kp-serverAuth             OBJECT IDENTIFIER ::= { id-kp 1 }
+//	id-kp-clientAuth             OBJECT IDENTIFIER ::= { id-kp 2 }
+//	id-kp-codeSigning            OBJECT IDENTIFIER ::= { id-kp 3 }
+//	id-kp-emailProtection        OBJECT IDENTIFIER ::= { id-kp 4 }
+//	id-kp-timeStamping           OBJECT IDENTIFIER ::= { id-kp 8 }
+//	id-kp-OCSPSigning            OBJECT IDENTIFIER ::= { id-kp 9 }
+var (
+	oidExtKeyUsageAny                            = asn1.ObjectIdentifier{2, 5, 29, 37, 0}
+	oidExtKeyUsageServerAuth                     = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 1}
+	oidExtKeyUsageClientAuth                     = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 2}
+	oidExtKeyUsageCodeSigning                    = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 3}
+	oidExtKeyUsageEmailProtection                = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 4}
+	oidExtKeyUsageIPSECEndSystem                 = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 5}
+	oidExtKeyUsageIPSECTunnel                    = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 6}
+	oidExtKeyUsageIPSECUser                      = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 7}
+	oidExtKeyUsageTimeStamping                   = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 8}
+	oidExtKeyUsageOCSPSigning                    = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 9}
+	oidExtKeyUsageMicrosoftServerGatedCrypto     = asn1.ObjectIdentifier{1, 3, 6, 1, 4, 1, 311, 10, 3, 3}
+	oidExtKeyUsageNetscapeServerGatedCrypto      = asn1.ObjectIdentifier{2, 16, 840, 1, 113730, 4, 1}
+	oidExtKeyUsageMicrosoftCommercialCodeSigning = asn1.ObjectIdentifier{1, 3, 6, 1, 4, 1, 311, 2, 1, 22}
+	oidExtKeyUsageMicrosoftKernelCodeSigning     = asn1.ObjectIdentifier{1, 3, 6, 1, 4, 1, 311, 61, 1, 1}
+)
+
+// ExtKeyUsage represents an extended set of actions that are valid for a given key.
+// Each of the ExtKeyUsage* constants define a unique action.
+type ExtKeyUsage int
+
+const (
+	ExtKeyUsageAny ExtKeyUsage = iota
+	ExtKeyUsageServerAuth
+	ExtKeyUsageClientAuth
+	ExtKeyUsageCodeSigning
+	ExtKeyUsageEmailProtection
+	ExtKeyUsageIPSECEndSystem
+	ExtKeyUsageIPSECTunnel
+	ExtKeyUsageIPSECUser
+	ExtKeyUsageTimeStamping
+	ExtKeyUsageOCSPSigning
+	ExtKeyUsageMicrosoftServerGatedCrypto
+	ExtKeyUsageNetscapeServerGatedCrypto
+	ExtKeyUsageMicrosoftCommercialCodeSigning
+	ExtKeyUsageMicrosoftKernelCodeSigning
+)
+
+// extKeyUsageOIDs contains the mapping between an ExtKeyUsage and its OID.
+var extKeyUsageOIDs = []struct {
+	extKeyUsage ExtKeyUsage
+	oid         asn1.ObjectIdentifier
+}{
+	{ExtKeyUsageAny, oidExtKeyUsageAny},
+	{ExtKeyUsageServerAuth, oidExtKeyUsageServerAuth},
+	{ExtKeyUsageClientAuth, oidExtKeyUsageClientAuth},
+	{ExtKeyUsageCodeSigning, oidExtKeyUsageCodeSigning},
+	{ExtKeyUsageEmailProtection, oidExtKeyUsageEmailProtection},
+	{ExtKeyUsageIPSECEndSystem, oidExtKeyUsageIPSECEndSystem},
+	{ExtKeyUsageIPSECTunnel, oidExtKeyUsageIPSECTunnel},
+	{ExtKeyUsageIPSECUser, oidExtKeyUsageIPSECUser},
+	{ExtKeyUsageTimeStamping, oidExtKeyUsageTimeStamping},
+	{ExtKeyUsageOCSPSigning, oidExtKeyUsageOCSPSigning},
+	{ExtKeyUsageMicrosoftServerGatedCrypto, oidExtKeyUsageMicrosoftServerGatedCrypto},
+	{ExtKeyUsageNetscapeServerGatedCrypto, oidExtKeyUsageNetscapeServerGatedCrypto},
+	{ExtKeyUsageMicrosoftCommercialCodeSigning, oidExtKeyUsageMicrosoftCommercialCodeSigning},
+	{ExtKeyUsageMicrosoftKernelCodeSigning, oidExtKeyUsageMicrosoftKernelCodeSigning},
+}
+
+func extKeyUsageFromOID(oid asn1.ObjectIdentifier) (eku ExtKeyUsage, ok bool) {
+	for _, pair := range extKeyUsageOIDs {
+		if oid.Equal(pair.oid) {
+			return pair.extKeyUsage, true
+		}
+	}
+	return
+}
+
+func oidFromExtKeyUsage(eku ExtKeyUsage) (oid asn1.ObjectIdentifier, ok bool) {
+	for _, pair := range extKeyUsageOIDs {
+		if eku == pair.extKeyUsage {
+			return pair.oid, true
+		}
+	}
+	return
+}
+
+// A Certificate represents an X.509 certificate.
+type Certificate struct {
+	Raw                     []byte // Complete ASN.1 DER content (certificate, signature algorithm and signature).
+	RawTBSCertificate       []byte // Certificate part of raw ASN.1 DER content.
+	RawSubjectPublicKeyInfo []byte // DER encoded SubjectPublicKeyInfo.
+	RawSubject              []byte // DER encoded Subject
+	RawIssuer               []byte // DER encoded Issuer
+
+	Signature          []byte
+	SignatureAlgorithm SignatureAlgorithm
+
+	PublicKeyAlgorithm PublicKeyAlgorithm
+	PublicKey          any
+
+	Version             int
+	SerialNumber        *big.Int
+	Issuer              pkix.Name
+	Subject             pkix.Name
+	NotBefore, NotAfter time.Time // Validity bounds.
+	KeyUsage            KeyUsage
+
+	// Extensions contains raw X.509 extensions. When parsing certificates,
+	// this can be used to extract non-critical extensions that are not
+	// parsed by this package. When marshaling certificates, the Extensions
+	// field is ignored, see ExtraExtensions.
+	Extensions []pkix.Extension
+
+	// ExtraExtensions contains extensions to be copied, raw, into any
+	// marshaled certificates. Values override any extensions that would
+	// otherwise be produced based on the other fields. The ExtraExtensions
+	// field is not populated when parsing certificates, see Extensions.
+	ExtraExtensions []pkix.Extension
+
+	// UnhandledCriticalExtensions contains a list of extension IDs that
+	// were not (fully) processed when parsing. Verify will fail if this
+	// slice is non-empty, unless verification is delegated to an OS
+	// library which understands all the critical extensions.
+	//
+	// Users can access these extensions using Extensions and can remove
+	// elements from this slice if they believe that they have been
+	// handled.
+	UnhandledCriticalExtensions []asn1.ObjectIdentifier
+
+	ExtKeyUsage        []ExtKeyUsage           // Sequence of extended key usages.
+	UnknownExtKeyUsage []asn1.ObjectIdentifier // Encountered extended key usages unknown to this package.
+
+	// BasicConstraintsValid indicates whether IsCA, MaxPathLen,
+	// and MaxPathLenZero are valid.
+	BasicConstraintsValid bool
+	IsCA                  bool
+
+	// MaxPathLen and MaxPathLenZero indicate the presence and
+	// value of the BasicConstraints' "pathLenConstraint".
+	//
+	// When parsing a certificate, a positive non-zero MaxPathLen
+	// means that the field was specified, -1 means it was unset,
+	// and MaxPathLenZero being true mean that the field was
+	// explicitly set to zero. The case of MaxPathLen==0 with MaxPathLenZero==false
+	// should be treated equivalent to -1 (unset).
+	//
+	// When generating a certificate, an unset pathLenConstraint
+	// can be requested with either MaxPathLen == -1 or using the
+	// zero value for both MaxPathLen and MaxPathLenZero.
+	MaxPathLen int
+	// MaxPathLenZero indicates that BasicConstraintsValid==true
+	// and MaxPathLen==0 should be interpreted as an actual
+	// maximum path length of zero. Otherwise, that combination is
+	// interpreted as MaxPathLen not being set.
+	MaxPathLenZero bool
+
+	SubjectKeyId   []byte
+	AuthorityKeyId []byte
+
+	// RFC 5280, 4.2.2.1 (Authority Information Access)
+	OCSPServer            []string
+	IssuingCertificateURL []string
+
+	// Subject Alternate Name values. (Note that these values may not be valid
+	// if invalid values were contained within a parsed certificate. For
+	// example, an element of DNSNames may not be a valid DNS domain name.)
+	DNSNames       []string
+	EmailAddresses []string
+	IPAddresses    []net.IP
+	URIs           []*url.URL
+
+	// Name constraints
+	PermittedDNSDomainsCritical bool // if true then the name constraints are marked critical.
+	PermittedDNSDomains         []string
+	ExcludedDNSDomains          []string
+	PermittedIPRanges           []*net.IPNet
+	ExcludedIPRanges            []*net.IPNet
+	PermittedEmailAddresses     []string
+	ExcludedEmailAddresses      []string
+	PermittedURIDomains         []string
+	ExcludedURIDomains          []string
+
+	// CRL Distribution Points
+	CRLDistributionPoints []string
+
+	PolicyIdentifiers []asn1.ObjectIdentifier
+}
+
+// ErrUnsupportedAlgorithm results from attempting to perform an operation that
+// involves algorithms that are not currently implemented.
+var ErrUnsupportedAlgorithm = errors.New("x509: cannot verify signature: algorithm unimplemented")
+
+// debugAllowSHA1 allows SHA-1 signatures. See issue 41682.
+var debugAllowSHA1 = godebug.Get("x509sha1") == "1"
+
+// An InsecureAlgorithmError indicates that the SignatureAlgorithm used to
+// generate the signature is not secure, and the signature has been rejected.
+//
+// To temporarily restore support for SHA-1 signatures, include the value
+// "x509sha1=1" in the GODEBUG environment variable. Note that this option will
+// be removed in a future release.
+type InsecureAlgorithmError SignatureAlgorithm
+
+func (e InsecureAlgorithmError) Error() string {
+	var override string
+	if SignatureAlgorithm(e) == SHA1WithRSA || SignatureAlgorithm(e) == ECDSAWithSHA1 {
+		override = " (temporarily override with GODEBUG=x509sha1=1)"
+	}
+	return fmt.Sprintf("x509: cannot verify signature: insecure algorithm %v", SignatureAlgorithm(e)) + override
+}
+
+// ConstraintViolationError results when a requested usage is not permitted by
+// a certificate. For example: checking a signature when the public key isn't a
+// certificate signing key.
+type ConstraintViolationError struct{}
+
+func (ConstraintViolationError) Error() string {
+	return "x509: invalid signature: parent certificate cannot sign this kind of certificate"
+}
+
+func (c *Certificate) Equal(other *Certificate) bool {
+	if c == nil || other == nil {
+		return c == other
+	}
+	return bytes.Equal(c.Raw, other.Raw)
+}
+
+func (c *Certificate) hasSANExtension() bool {
+	return oidInExtensions(oidExtensionSubjectAltName, c.Extensions)
+}
+
+// CheckSignatureFrom verifies that the signature on c is a valid signature
+// from parent. SHA1WithRSA and ECDSAWithSHA1 signatures are not supported.
+func (c *Certificate) CheckSignatureFrom(parent *Certificate) error {
+	// RFC 5280, 4.2.1.9:
+	// "If the basic constraints extension is not present in a version 3
+	// certificate, or the extension is present but the cA boolean is not
+	// asserted, then the certified public key MUST NOT be used to verify
+	// certificate signatures."
+	if parent.Version == 3 && !parent.BasicConstraintsValid ||
+		parent.BasicConstraintsValid && !parent.IsCA {
+		return ConstraintViolationError{}
+	}
+
+	if parent.KeyUsage != 0 && parent.KeyUsage&KeyUsageCertSign == 0 {
+		return ConstraintViolationError{}
+	}
+
+	if parent.PublicKeyAlgorithm == UnknownPublicKeyAlgorithm {
+		return ErrUnsupportedAlgorithm
+	}
+
+	// TODO(agl): don't ignore the path length constraint.
+
+	return checkSignature(c.SignatureAlgorithm, c.RawTBSCertificate, c.Signature, parent.PublicKey, debugAllowSHA1)
+}
+
+// CheckSignature verifies that signature is a valid signature over signed from
+// c's public key.
+func (c *Certificate) CheckSignature(algo SignatureAlgorithm, signed, signature []byte) error {
+	return checkSignature(algo, signed, signature, c.PublicKey, true)
+}
+
+func (c *Certificate) hasNameConstraints() bool {
+	return oidInExtensions(oidExtensionNameConstraints, c.Extensions)
+}
+
+func (c *Certificate) getSANExtension() []byte {
+	for _, e := range c.Extensions {
+		if e.Id.Equal(oidExtensionSubjectAltName) {
+			return e.Value
+		}
+	}
+	return nil
+}
+
+func signaturePublicKeyAlgoMismatchError(expectedPubKeyAlgo PublicKeyAlgorithm, pubKey any) error {
+	return fmt.Errorf("x509: signature algorithm specifies an %s public key, but have public key of type %T", expectedPubKeyAlgo.String(), pubKey)
+}
+
+// checkSignature verifies that signature is a valid signature over signed from
+// a crypto.PublicKey.
+func checkSignature(algo SignatureAlgorithm, signed, signature []byte, publicKey crypto.PublicKey, allowSHA1 bool) (err error) {
+	var hashType crypto.Hash
+	var pubKeyAlgo PublicKeyAlgorithm
+
+	for _, details := range signatureAlgorithmDetails {
+		if details.algo == algo {
+			hashType = details.hash
+			pubKeyAlgo = details.pubKeyAlgo
+		}
+	}
+
+	switch hashType {
+	case crypto.Hash(0):
+		if pubKeyAlgo != Ed25519 {
+			return ErrUnsupportedAlgorithm
+		}
+	case crypto.MD5:
+		return InsecureAlgorithmError(algo)
+	case crypto.SHA1:
+		if !allowSHA1 {
+			return InsecureAlgorithmError(algo)
+		}
+		fallthrough
+	default:
+		if !hashType.Available() {
+			return ErrUnsupportedAlgorithm
+		}
+		h := hashType.New()
+		h.Write(signed)
+		signed = h.Sum(nil)
+	}
+
+	switch pub := publicKey.(type) {
+	case *rsa.PublicKey:
+		if pubKeyAlgo != RSA {
+			return signaturePublicKeyAlgoMismatchError(pubKeyAlgo, pub)
+		}
+		if algo.isRSAPSS() {
+			return rsa.VerifyPSS(pub, hashType, signed, signature, &rsa.PSSOptions{SaltLength: rsa.PSSSaltLengthEqualsHash})
+		} else {
+			return rsa.VerifyPKCS1v15(pub, hashType, signed, signature)
+		}
+	case *ecdsa.PublicKey:
+		if pubKeyAlgo != ECDSA {
+			return signaturePublicKeyAlgoMismatchError(pubKeyAlgo, pub)
+		}
+		if !ecdsa.VerifyASN1(pub, signed, signature) {
+			return errors.New("x509: ECDSA verification failure")
+		}
+		return
+	case ed25519.PublicKey:
+		if pubKeyAlgo != Ed25519 {
+			return signaturePublicKeyAlgoMismatchError(pubKeyAlgo, pub)
+		}
+		if !ed25519.Verify(pub, signed, signature) {
+			return errors.New("x509: Ed25519 verification failure")
+		}
+		return
+	}
+	return ErrUnsupportedAlgorithm
+}
+
+// CheckCRLSignature checks that the signature in crl is from c.
+//
+// Deprecated: Use RevocationList.CheckSignatureFrom instead.
+func (c *Certificate) CheckCRLSignature(crl *pkix.CertificateList) error {
+	algo := getSignatureAlgorithmFromAI(crl.SignatureAlgorithm)
+	return c.CheckSignature(algo, crl.TBSCertList.Raw, crl.SignatureValue.RightAlign())
+}
+
+type UnhandledCriticalExtension struct{}
+
+func (h UnhandledCriticalExtension) Error() string {
+	return "x509: unhandled critical extension"
+}
+
+type basicConstraints struct {
+	IsCA       bool `asn1:"optional"`
+	MaxPathLen int  `asn1:"optional,default:-1"`
+}
+
+// RFC 5280 4.2.1.4
+type policyInformation struct {
+	Policy asn1.ObjectIdentifier
+	// policyQualifiers omitted
+}
+
+const (
+	nameTypeEmail = 1
+	nameTypeDNS   = 2
+	nameTypeURI   = 6
+	nameTypeIP    = 7
+)
+
+// RFC 5280, 4.2.2.1
+type authorityInfoAccess struct {
+	Method   asn1.ObjectIdentifier
+	Location asn1.RawValue
+}
+
+// RFC 5280, 4.2.1.14
+type distributionPoint struct {
+	DistributionPoint distributionPointName `asn1:"optional,tag:0"`
+	Reason            asn1.BitString        `asn1:"optional,tag:1"`
+	CRLIssuer         asn1.RawValue         `asn1:"optional,tag:2"`
+}
+
+type distributionPointName struct {
+	FullName     []asn1.RawValue  `asn1:"optional,tag:0"`
+	RelativeName pkix.RDNSequence `asn1:"optional,tag:1"`
+}
+
+func reverseBitsInAByte(in byte) byte {
+	b1 := in>>4 | in<<4
+	b2 := b1>>2&0x33 | b1<<2&0xcc
+	b3 := b2>>1&0x55 | b2<<1&0xaa
+	return b3
+}
+
+// asn1BitLength returns the bit-length of bitString by considering the
+// most-significant bit in a byte to be the "first" bit. This convention
+// matches ASN.1, but differs from almost everything else.
+func asn1BitLength(bitString []byte) int {
+	bitLen := len(bitString) * 8
+
+	for i := range bitString {
+		b := bitString[len(bitString)-i-1]
+
+		for bit := uint(0); bit < 8; bit++ {
+			if (b>>bit)&1 == 1 {
+				return bitLen
+			}
+			bitLen--
+		}
+	}
+
+	return 0
+}
+
+var (
+	oidExtensionSubjectKeyId          = []int{2, 5, 29, 14}
+	oidExtensionKeyUsage              = []int{2, 5, 29, 15}
+	oidExtensionExtendedKeyUsage      = []int{2, 5, 29, 37}
+	oidExtensionAuthorityKeyId        = []int{2, 5, 29, 35}
+	oidExtensionBasicConstraints      = []int{2, 5, 29, 19}
+	oidExtensionSubjectAltName        = []int{2, 5, 29, 17}
+	oidExtensionCertificatePolicies   = []int{2, 5, 29, 32}
+	oidExtensionNameConstraints       = []int{2, 5, 29, 30}
+	oidExtensionCRLDistributionPoints = []int{2, 5, 29, 31}
+	oidExtensionAuthorityInfoAccess   = []int{1, 3, 6, 1, 5, 5, 7, 1, 1}
+	oidExtensionCRLNumber             = []int{2, 5, 29, 20}
+)
+
+var (
+	oidAuthorityInfoAccessOcsp    = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 48, 1}
+	oidAuthorityInfoAccessIssuers = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 48, 2}
+)
+
+// oidNotInExtensions reports whether an extension with the given oid exists in
+// extensions.
+func oidInExtensions(oid asn1.ObjectIdentifier, extensions []pkix.Extension) bool {
+	for _, e := range extensions {
+		if e.Id.Equal(oid) {
+			return true
+		}
+	}
+	return false
+}
+
+// marshalSANs marshals a list of addresses into a the contents of an X.509
+// SubjectAlternativeName extension.
+func marshalSANs(dnsNames, emailAddresses []string, ipAddresses []net.IP, uris []*url.URL) (derBytes []byte, err error) {
+	var rawValues []asn1.RawValue
+	for _, name := range dnsNames {
+		if err := isIA5String(name); err != nil {
+			return nil, err
+		}
+		rawValues = append(rawValues, asn1.RawValue{Tag: nameTypeDNS, Class: 2, Bytes: []byte(name)})
+	}
+	for _, email := range emailAddresses {
+		if err := isIA5String(email); err != nil {
+			return nil, err
+		}
+		rawValues = append(rawValues, asn1.RawValue{Tag: nameTypeEmail, Class: 2, Bytes: []byte(email)})
+	}
+	for _, rawIP := range ipAddresses {
+		// If possible, we always want to encode IPv4 addresses in 4 bytes.
+		ip := rawIP.To4()
+		if ip == nil {
+			ip = rawIP
+		}
+		rawValues = append(rawValues, asn1.RawValue{Tag: nameTypeIP, Class: 2, Bytes: ip})
+	}
+	for _, uri := range uris {
+		uriStr := uri.String()
+		if err := isIA5String(uriStr); err != nil {
+			return nil, err
+		}
+		rawValues = append(rawValues, asn1.RawValue{Tag: nameTypeURI, Class: 2, Bytes: []byte(uriStr)})
+	}
+	return asn1.Marshal(rawValues)
+}
+
+func isIA5String(s string) error {
+	for _, r := range s {
+		// Per RFC5280 "IA5String is limited to the set of ASCII characters"
+		if r > unicode.MaxASCII {
+			return fmt.Errorf("x509: %q cannot be encoded as an IA5String", s)
+		}
+	}
+
+	return nil
+}
+
+func buildCertExtensions(template *Certificate, subjectIsEmpty bool, authorityKeyId []byte, subjectKeyId []byte) (ret []pkix.Extension, err error) {
+	ret = make([]pkix.Extension, 10 /* maximum number of elements. */)
+	n := 0
+
+	if template.KeyUsage != 0 &&
+		!oidInExtensions(oidExtensionKeyUsage, template.ExtraExtensions) {
+		ret[n], err = marshalKeyUsage(template.KeyUsage)
+		if err != nil {
+			return nil, err
+		}
+		n++
+	}
+
+	if (len(template.ExtKeyUsage) > 0 || len(template.UnknownExtKeyUsage) > 0) &&
+		!oidInExtensions(oidExtensionExtendedKeyUsage, template.ExtraExtensions) {
+		ret[n], err = marshalExtKeyUsage(template.ExtKeyUsage, template.UnknownExtKeyUsage)
+		if err != nil {
+			return nil, err
+		}
+		n++
+	}
+
+	if template.BasicConstraintsValid && !oidInExtensions(oidExtensionBasicConstraints, template.ExtraExtensions) {
+		ret[n], err = marshalBasicConstraints(template.IsCA, template.MaxPathLen, template.MaxPathLenZero)
+		if err != nil {
+			return nil, err
+		}
+		n++
+	}
+
+	if len(subjectKeyId) > 0 && !oidInExtensions(oidExtensionSubjectKeyId, template.ExtraExtensions) {
+		ret[n].Id = oidExtensionSubjectKeyId
+		ret[n].Value, err = asn1.Marshal(subjectKeyId)
+		if err != nil {
+			return
+		}
+		n++
+	}
+
+	if len(authorityKeyId) > 0 && !oidInExtensions(oidExtensionAuthorityKeyId, template.ExtraExtensions) {
+		ret[n].Id = oidExtensionAuthorityKeyId
+		ret[n].Value, err = asn1.Marshal(authKeyId{authorityKeyId})
+		if err != nil {
+			return
+		}
+		n++
+	}
+
+	if (len(template.OCSPServer) > 0 || len(template.IssuingCertificateURL) > 0) &&
+		!oidInExtensions(oidExtensionAuthorityInfoAccess, template.ExtraExtensions) {
+		ret[n].Id = oidExtensionAuthorityInfoAccess
+		var aiaValues []authorityInfoAccess
+		for _, name := range template.OCSPServer {
+			aiaValues = append(aiaValues, authorityInfoAccess{
+				Method:   oidAuthorityInfoAccessOcsp,
+				Location: asn1.RawValue{Tag: 6, Class: 2, Bytes: []byte(name)},
+			})
+		}
+		for _, name := range template.IssuingCertificateURL {
+			aiaValues = append(aiaValues, authorityInfoAccess{
+				Method:   oidAuthorityInfoAccessIssuers,
+				Location: asn1.RawValue{Tag: 6, Class: 2, Bytes: []byte(name)},
+			})
+		}
+		ret[n].Value, err = asn1.Marshal(aiaValues)
+		if err != nil {
+			return
+		}
+		n++
+	}
+
+	if (len(template.DNSNames) > 0 || len(template.EmailAddresses) > 0 || len(template.IPAddresses) > 0 || len(template.URIs) > 0) &&
+		!oidInExtensions(oidExtensionSubjectAltName, template.ExtraExtensions) {
+		ret[n].Id = oidExtensionSubjectAltName
+		// From RFC 5280, Section 4.2.1.6:
+		// “If the subject field contains an empty sequence ... then
+		// subjectAltName extension ... is marked as critical”
+		ret[n].Critical = subjectIsEmpty
+		ret[n].Value, err = marshalSANs(template.DNSNames, template.EmailAddresses, template.IPAddresses, template.URIs)
+		if err != nil {
+			return
+		}
+		n++
+	}
+
+	if len(template.PolicyIdentifiers) > 0 &&
+		!oidInExtensions(oidExtensionCertificatePolicies, template.ExtraExtensions) {
+		ret[n], err = marshalCertificatePolicies(template.PolicyIdentifiers)
+		if err != nil {
+			return nil, err
+		}
+		n++
+	}
+
+	if (len(template.PermittedDNSDomains) > 0 || len(template.ExcludedDNSDomains) > 0 ||
+		len(template.PermittedIPRanges) > 0 || len(template.ExcludedIPRanges) > 0 ||
+		len(template.PermittedEmailAddresses) > 0 || len(template.ExcludedEmailAddresses) > 0 ||
+		len(template.PermittedURIDomains) > 0 || len(template.ExcludedURIDomains) > 0) &&
+		!oidInExtensions(oidExtensionNameConstraints, template.ExtraExtensions) {
+		ret[n].Id = oidExtensionNameConstraints
+		ret[n].Critical = template.PermittedDNSDomainsCritical
+
+		ipAndMask := func(ipNet *net.IPNet) []byte {
+			maskedIP := ipNet.IP.Mask(ipNet.Mask)
+			ipAndMask := make([]byte, 0, len(maskedIP)+len(ipNet.Mask))
+			ipAndMask = append(ipAndMask, maskedIP...)
+			ipAndMask = append(ipAndMask, ipNet.Mask...)
+			return ipAndMask
+		}
+
+		serialiseConstraints := func(dns []string, ips []*net.IPNet, emails []string, uriDomains []string) (der []byte, err error) {
+			var b cryptobyte.Builder
+
+			for _, name := range dns {
+				if err = isIA5String(name); err != nil {
+					return nil, err
+				}
+
+				b.AddASN1(cryptobyte_asn1.SEQUENCE, func(b *cryptobyte.Builder) {
+					b.AddASN1(cryptobyte_asn1.Tag(2).ContextSpecific(), func(b *cryptobyte.Builder) {
+						b.AddBytes([]byte(name))
+					})
+				})
+			}
+
+			for _, ipNet := range ips {
+				b.AddASN1(cryptobyte_asn1.SEQUENCE, func(b *cryptobyte.Builder) {
+					b.AddASN1(cryptobyte_asn1.Tag(7).ContextSpecific(), func(b *cryptobyte.Builder) {
+						b.AddBytes(ipAndMask(ipNet))
+					})
+				})
+			}
+
+			for _, email := range emails {
+				if err = isIA5String(email); err != nil {
+					return nil, err
+				}
+
+				b.AddASN1(cryptobyte_asn1.SEQUENCE, func(b *cryptobyte.Builder) {
+					b.AddASN1(cryptobyte_asn1.Tag(1).ContextSpecific(), func(b *cryptobyte.Builder) {
+						b.AddBytes([]byte(email))
+					})
+				})
+			}
+
+			for _, uriDomain := range uriDomains {
+				if err = isIA5String(uriDomain); err != nil {
+					return nil, err
+				}
+
+				b.AddASN1(cryptobyte_asn1.SEQUENCE, func(b *cryptobyte.Builder) {
+					b.AddASN1(cryptobyte_asn1.Tag(6).ContextSpecific(), func(b *cryptobyte.Builder) {
+						b.AddBytes([]byte(uriDomain))
+					})
+				})
+			}
+
+			return b.Bytes()
+		}
+
+		permitted, err := serialiseConstraints(template.PermittedDNSDomains, template.PermittedIPRanges, template.PermittedEmailAddresses, template.PermittedURIDomains)
+		if err != nil {
+			return nil, err
+		}
+
+		excluded, err := serialiseConstraints(template.ExcludedDNSDomains, template.ExcludedIPRanges, template.ExcludedEmailAddresses, template.ExcludedURIDomains)
+		if err != nil {
+			return nil, err
+		}
+
+		var b cryptobyte.Builder
+		b.AddASN1(cryptobyte_asn1.SEQUENCE, func(b *cryptobyte.Builder) {
+			if len(permitted) > 0 {
+				b.AddASN1(cryptobyte_asn1.Tag(0).ContextSpecific().Constructed(), func(b *cryptobyte.Builder) {
+					b.AddBytes(permitted)
+				})
+			}
+
+			if len(excluded) > 0 {
+				b.AddASN1(cryptobyte_asn1.Tag(1).ContextSpecific().Constructed(), func(b *cryptobyte.Builder) {
+					b.AddBytes(excluded)
+				})
+			}
+		})
+
+		ret[n].Value, err = b.Bytes()
+		if err != nil {
+			return nil, err
+		}
+		n++
+	}
+
+	if len(template.CRLDistributionPoints) > 0 &&
+		!oidInExtensions(oidExtensionCRLDistributionPoints, template.ExtraExtensions) {
+		ret[n].Id = oidExtensionCRLDistributionPoints
+
+		var crlDp []distributionPoint
+		for _, name := range template.CRLDistributionPoints {
+			dp := distributionPoint{
+				DistributionPoint: distributionPointName{
+					FullName: []asn1.RawValue{
+						{Tag: 6, Class: 2, Bytes: []byte(name)},
+					},
+				},
+			}
+			crlDp = append(crlDp, dp)
+		}
+
+		ret[n].Value, err = asn1.Marshal(crlDp)
+		if err != nil {
+			return
+		}
+		n++
+	}
+
+	// Adding another extension here? Remember to update the maximum number
+	// of elements in the make() at the top of the function and the list of
+	// template fields used in CreateCertificate documentation.
+
+	return append(ret[:n], template.ExtraExtensions...), nil
+}
+
+func marshalKeyUsage(ku KeyUsage) (pkix.Extension, error) {
+	ext := pkix.Extension{Id: oidExtensionKeyUsage, Critical: true}
+
+	var a [2]byte
+	a[0] = reverseBitsInAByte(byte(ku))
+	a[1] = reverseBitsInAByte(byte(ku >> 8))
+
+	l := 1
+	if a[1] != 0 {
+		l = 2
+	}
+
+	bitString := a[:l]
+	var err error
+	ext.Value, err = asn1.Marshal(asn1.BitString{Bytes: bitString, BitLength: asn1BitLength(bitString)})
+	return ext, err
+}
+
+func marshalExtKeyUsage(extUsages []ExtKeyUsage, unknownUsages []asn1.ObjectIdentifier) (pkix.Extension, error) {
+	ext := pkix.Extension{Id: oidExtensionExtendedKeyUsage}
+
+	oids := make([]asn1.ObjectIdentifier, len(extUsages)+len(unknownUsages))
+	for i, u := range extUsages {
+		if oid, ok := oidFromExtKeyUsage(u); ok {
+			oids[i] = oid
+		} else {
+			return ext, errors.New("x509: unknown extended key usage")
+		}
+	}
+
+	copy(oids[len(extUsages):], unknownUsages)
+
+	var err error
+	ext.Value, err = asn1.Marshal(oids)
+	return ext, err
+}
+
+func marshalBasicConstraints(isCA bool, maxPathLen int, maxPathLenZero bool) (pkix.Extension, error) {
+	ext := pkix.Extension{Id: oidExtensionBasicConstraints, Critical: true}
+	// Leaving MaxPathLen as zero indicates that no maximum path
+	// length is desired, unless MaxPathLenZero is set. A value of
+	// -1 causes encoding/asn1 to omit the value as desired.
+	if maxPathLen == 0 && !maxPathLenZero {
+		maxPathLen = -1
+	}
+	var err error
+	ext.Value, err = asn1.Marshal(basicConstraints{isCA, maxPathLen})
+	return ext, err
+}
+
+func marshalCertificatePolicies(policyIdentifiers []asn1.ObjectIdentifier) (pkix.Extension, error) {
+	ext := pkix.Extension{Id: oidExtensionCertificatePolicies}
+	policies := make([]policyInformation, len(policyIdentifiers))
+	for i, policy := range policyIdentifiers {
+		policies[i].Policy = policy
+	}
+	var err error
+	ext.Value, err = asn1.Marshal(policies)
+	return ext, err
+}
+
+func buildCSRExtensions(template *CertificateRequest) ([]pkix.Extension, error) {
+	var ret []pkix.Extension
+
+	if (len(template.DNSNames) > 0 || len(template.EmailAddresses) > 0 || len(template.IPAddresses) > 0 || len(template.URIs) > 0) &&
+		!oidInExtensions(oidExtensionSubjectAltName, template.ExtraExtensions) {
+		sanBytes, err := marshalSANs(template.DNSNames, template.EmailAddresses, template.IPAddresses, template.URIs)
+		if err != nil {
+			return nil, err
+		}
+
+		ret = append(ret, pkix.Extension{
+			Id:    oidExtensionSubjectAltName,
+			Value: sanBytes,
+		})
+	}
+
+	return append(ret, template.ExtraExtensions...), nil
+}
+
+func subjectBytes(cert *Certificate) ([]byte, error) {
+	if len(cert.RawSubject) > 0 {
+		return cert.RawSubject, nil
+	}
+
+	return asn1.Marshal(cert.Subject.ToRDNSequence())
+}
+
+// signingParamsForPublicKey returns the parameters to use for signing with
+// priv. If requestedSigAlgo is not zero then it overrides the default
+// signature algorithm.
+func signingParamsForPublicKey(pub any, requestedSigAlgo SignatureAlgorithm) (hashFunc crypto.Hash, sigAlgo pkix.AlgorithmIdentifier, err error) {
+	var pubType PublicKeyAlgorithm
+
+	switch pub := pub.(type) {
+	case *rsa.PublicKey:
+		pubType = RSA
+		hashFunc = crypto.SHA256
+		sigAlgo.Algorithm = oidSignatureSHA256WithRSA
+		sigAlgo.Parameters = asn1.NullRawValue
+
+	case *ecdsa.PublicKey:
+		pubType = ECDSA
+
+		switch pub.Curve {
+		case elliptic.P224(), elliptic.P256():
+			hashFunc = crypto.SHA256
+			sigAlgo.Algorithm = oidSignatureECDSAWithSHA256
+		case elliptic.P384():
+			hashFunc = crypto.SHA384
+			sigAlgo.Algorithm = oidSignatureECDSAWithSHA384
+		case elliptic.P521():
+			hashFunc = crypto.SHA512
+			sigAlgo.Algorithm = oidSignatureECDSAWithSHA512
+		default:
+			err = errors.New("x509: unknown elliptic curve")
+		}
+
+	case ed25519.PublicKey:
+		pubType = Ed25519
+		sigAlgo.Algorithm = oidSignatureEd25519
+
+	default:
+		err = errors.New("x509: only RSA, ECDSA and Ed25519 keys supported")
+	}
+
+	if err != nil {
+		return
+	}
+
+	if requestedSigAlgo == 0 {
+		return
+	}
+
+	found := false
+	for _, details := range signatureAlgorithmDetails {
+		if details.algo == requestedSigAlgo {
+			if details.pubKeyAlgo != pubType {
+				err = errors.New("x509: requested SignatureAlgorithm does not match private key type")
+				return
+			}
+			sigAlgo.Algorithm, hashFunc = details.oid, details.hash
+			if hashFunc == 0 && pubType != Ed25519 {
+				err = errors.New("x509: cannot sign with hash function requested")
+				return
+			}
+			if hashFunc == crypto.MD5 {
+				err = errors.New("x509: signing with MD5 is not supported")
+				return
+			}
+			if requestedSigAlgo.isRSAPSS() {
+				sigAlgo.Parameters = hashToPSSParameters[hashFunc]
+			}
+			found = true
+			break
+		}
+	}
+
+	if !found {
+		err = errors.New("x509: unknown SignatureAlgorithm")
+	}
+
+	return
+}
+
+// emptyASN1Subject is the ASN.1 DER encoding of an empty Subject, which is
+// just an empty SEQUENCE.
+var emptyASN1Subject = []byte{0x30, 0}
+
+// CreateCertificate creates a new X.509 v3 certificate based on a template.
+// The following members of template are currently used:
+//
+//   - AuthorityKeyId
+//   - BasicConstraintsValid
+//   - CRLDistributionPoints
+//   - DNSNames
+//   - EmailAddresses
+//   - ExcludedDNSDomains
+//   - ExcludedEmailAddresses
+//   - ExcludedIPRanges
+//   - ExcludedURIDomains
+//   - ExtKeyUsage
+//   - ExtraExtensions
+//   - IPAddresses
+//   - IsCA
+//   - IssuingCertificateURL
+//   - KeyUsage
+//   - MaxPathLen
+//   - MaxPathLenZero
+//   - NotAfter
+//   - NotBefore
+//   - OCSPServer
+//   - PermittedDNSDomains
+//   - PermittedDNSDomainsCritical
+//   - PermittedEmailAddresses
+//   - PermittedIPRanges
+//   - PermittedURIDomains
+//   - PolicyIdentifiers
+//   - SerialNumber
+//   - SignatureAlgorithm
+//   - Subject
+//   - SubjectKeyId
+//   - URIs
+//   - UnknownExtKeyUsage
+//
+// The certificate is signed by parent. If parent is equal to template then the
+// certificate is self-signed. The parameter pub is the public key of the
+// certificate to be generated and priv is the private key of the signer.
+//
+// The returned slice is the certificate in DER encoding.
+//
+// The currently supported key types are *rsa.PublicKey, *ecdsa.PublicKey and
+// ed25519.PublicKey. pub must be a supported key type, and priv must be a
+// crypto.Signer with a supported public key.
+//
+// The AuthorityKeyId will be taken from the SubjectKeyId of parent, if any,
+// unless the resulting certificate is self-signed. Otherwise the value from
+// template will be used.
+//
+// If SubjectKeyId from template is empty and the template is a CA, SubjectKeyId
+// will be generated from the hash of the public key.
+func CreateCertificate(rand io.Reader, template, parent *Certificate, pub, priv any) ([]byte, error) {
+	key, ok := priv.(crypto.Signer)
+	if !ok {
+		return nil, errors.New("x509: certificate private key does not implement crypto.Signer")
+	}
+
+	if template.SerialNumber == nil {
+		return nil, errors.New("x509: no SerialNumber given")
+	}
+
+	// RFC 5280 Section 4.1.2.2: serial number must positive
+	//
+	// We _should_ also restrict serials to <= 20 octets, but it turns out a lot of people
+	// get this wrong, in part because the encoding can itself alter the length of the
+	// serial. For now we accept these non-conformant serials.
+	if template.SerialNumber.Sign() == -1 {
+		return nil, errors.New("x509: serial number must be positive")
+	}
+
+	if template.BasicConstraintsValid && !template.IsCA && template.MaxPathLen != -1 && (template.MaxPathLen != 0 || template.MaxPathLenZero) {
+		return nil, errors.New("x509: only CAs are allowed to specify MaxPathLen")
+	}
+
+	hashFunc, signatureAlgorithm, err := signingParamsForPublicKey(key.Public(), template.SignatureAlgorithm)
+	if err != nil {
+		return nil, err
+	}
+
+	publicKeyBytes, publicKeyAlgorithm, err := marshalPublicKey(pub)
+	if err != nil {
+		return nil, err
+	}
+
+	asn1Issuer, err := subjectBytes(parent)
+	if err != nil {
+		return nil, err
+	}
+
+	asn1Subject, err := subjectBytes(template)
+	if err != nil {
+		return nil, err
+	}
+
+	authorityKeyId := template.AuthorityKeyId
+	if !bytes.Equal(asn1Issuer, asn1Subject) && len(parent.SubjectKeyId) > 0 {
+		authorityKeyId = parent.SubjectKeyId
+	}
+
+	subjectKeyId := template.SubjectKeyId
+	if len(subjectKeyId) == 0 && template.IsCA {
+		// SubjectKeyId generated using method 1 in RFC 5280, Section 4.2.1.2:
+		//   (1) The keyIdentifier is composed of the 160-bit SHA-1 hash of the
+		//   value of the BIT STRING subjectPublicKey (excluding the tag,
+		//   length, and number of unused bits).
+		h := sha1.Sum(publicKeyBytes)
+		subjectKeyId = h[:]
+	}
+
+	// Check that the signer's public key matches the private key, if available.
+	type privateKey interface {
+		Equal(crypto.PublicKey) bool
+	}
+	if privPub, ok := key.Public().(privateKey); !ok {
+		return nil, errors.New("x509: internal error: supported public key does not implement Equal")
+	} else if parent.PublicKey != nil && !privPub.Equal(parent.PublicKey) {
+		return nil, errors.New("x509: provided PrivateKey doesn't match parent's PublicKey")
+	}
+
+	extensions, err := buildCertExtensions(template, bytes.Equal(asn1Subject, emptyASN1Subject), authorityKeyId, subjectKeyId)
+	if err != nil {
+		return nil, err
+	}
+
+	encodedPublicKey := asn1.BitString{BitLength: len(publicKeyBytes) * 8, Bytes: publicKeyBytes}
+	c := tbsCertificate{
+		Version:            2,
+		SerialNumber:       template.SerialNumber,
+		SignatureAlgorithm: signatureAlgorithm,
+		Issuer:             asn1.RawValue{FullBytes: asn1Issuer},
+		Validity:           validity{template.NotBefore.UTC(), template.NotAfter.UTC()},
+		Subject:            asn1.RawValue{FullBytes: asn1Subject},
+		PublicKey:          publicKeyInfo{nil, publicKeyAlgorithm, encodedPublicKey},
+		Extensions:         extensions,
+	}
+
+	tbsCertContents, err := asn1.Marshal(c)
+	if err != nil {
+		return nil, err
+	}
+	c.Raw = tbsCertContents
+
+	signed := tbsCertContents
+	if hashFunc != 0 {
+		h := hashFunc.New()
+		h.Write(signed)
+		signed = h.Sum(nil)
+	}
+
+	var signerOpts crypto.SignerOpts = hashFunc
+	if template.SignatureAlgorithm != 0 && template.SignatureAlgorithm.isRSAPSS() {
+		signerOpts = &rsa.PSSOptions{
+			SaltLength: rsa.PSSSaltLengthEqualsHash,
+			Hash:       hashFunc,
+		}
+	}
+
+	var signature []byte
+	signature, err = key.Sign(rand, signed, signerOpts)
+	if err != nil {
+		return nil, err
+	}
+
+	signedCert, err := asn1.Marshal(certificate{
+		nil,
+		c,
+		signatureAlgorithm,
+		asn1.BitString{Bytes: signature, BitLength: len(signature) * 8},
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	// Check the signature to ensure the crypto.Signer behaved correctly.
+	if err := checkSignature(getSignatureAlgorithmFromAI(signatureAlgorithm), c.Raw, signature, key.Public(), true); err != nil {
+		return nil, fmt.Errorf("x509: signature over certificate returned by signer is invalid: %w", err)
+	}
+
+	return signedCert, nil
+}
+
+// pemCRLPrefix is the magic string that indicates that we have a PEM encoded
+// CRL.
+var pemCRLPrefix = []byte("-----BEGIN X509 CRL")
+
+// pemType is the type of a PEM encoded CRL.
+var pemType = "X509 CRL"
+
+// ParseCRL parses a CRL from the given bytes. It's often the case that PEM
+// encoded CRLs will appear where they should be DER encoded, so this function
+// will transparently handle PEM encoding as long as there isn't any leading
+// garbage.
+//
+// Deprecated: Use ParseRevocationList instead.
+func ParseCRL(crlBytes []byte) (*pkix.CertificateList, error) {
+	if bytes.HasPrefix(crlBytes, pemCRLPrefix) {
+		block, _ := pem.Decode(crlBytes)
+		if block != nil && block.Type == pemType {
+			crlBytes = block.Bytes
+		}
+	}
+	return ParseDERCRL(crlBytes)
+}
+
+// ParseDERCRL parses a DER encoded CRL from the given bytes.
+//
+// Deprecated: Use ParseRevocationList instead.
+func ParseDERCRL(derBytes []byte) (*pkix.CertificateList, error) {
+	certList := new(pkix.CertificateList)
+	if rest, err := asn1.Unmarshal(derBytes, certList); err != nil {
+		return nil, err
+	} else if len(rest) != 0 {
+		return nil, errors.New("x509: trailing data after CRL")
+	}
+	return certList, nil
+}
+
+// CreateCRL returns a DER encoded CRL, signed by this Certificate, that
+// contains the given list of revoked certificates.
+//
+// Deprecated: this method does not generate an RFC 5280 conformant X.509 v2 CRL.
+// To generate a standards compliant CRL, use CreateRevocationList instead.
+func (c *Certificate) CreateCRL(rand io.Reader, priv any, revokedCerts []pkix.RevokedCertificate, now, expiry time.Time) (crlBytes []byte, err error) {
+	key, ok := priv.(crypto.Signer)
+	if !ok {
+		return nil, errors.New("x509: certificate private key does not implement crypto.Signer")
+	}
+
+	hashFunc, signatureAlgorithm, err := signingParamsForPublicKey(key.Public(), 0)
+	if err != nil {
+		return nil, err
+	}
+
+	// Force revocation times to UTC per RFC 5280.
+	revokedCertsUTC := make([]pkix.RevokedCertificate, len(revokedCerts))
+	for i, rc := range revokedCerts {
+		rc.RevocationTime = rc.RevocationTime.UTC()
+		revokedCertsUTC[i] = rc
+	}
+
+	tbsCertList := pkix.TBSCertificateList{
+		Version:             1,
+		Signature:           signatureAlgorithm,
+		Issuer:              c.Subject.ToRDNSequence(),
+		ThisUpdate:          now.UTC(),
+		NextUpdate:          expiry.UTC(),
+		RevokedCertificates: revokedCertsUTC,
+	}
+
+	// Authority Key Id
+	if len(c.SubjectKeyId) > 0 {
+		var aki pkix.Extension
+		aki.Id = oidExtensionAuthorityKeyId
+		aki.Value, err = asn1.Marshal(authKeyId{Id: c.SubjectKeyId})
+		if err != nil {
+			return
+		}
+		tbsCertList.Extensions = append(tbsCertList.Extensions, aki)
+	}
+
+	tbsCertListContents, err := asn1.Marshal(tbsCertList)
+	if err != nil {
+		return
+	}
+
+	signed := tbsCertListContents
+	if hashFunc != 0 {
+		h := hashFunc.New()
+		h.Write(signed)
+		signed = h.Sum(nil)
+	}
+
+	var signature []byte
+	signature, err = key.Sign(rand, signed, hashFunc)
+	if err != nil {
+		return
+	}
+
+	return asn1.Marshal(pkix.CertificateList{
+		TBSCertList:        tbsCertList,
+		SignatureAlgorithm: signatureAlgorithm,
+		SignatureValue:     asn1.BitString{Bytes: signature, BitLength: len(signature) * 8},
+	})
+}
+
+// CertificateRequest represents a PKCS #10, certificate signature request.
+type CertificateRequest struct {
+	Raw                      []byte // Complete ASN.1 DER content (CSR, signature algorithm and signature).
+	RawTBSCertificateRequest []byte // Certificate request info part of raw ASN.1 DER content.
+	RawSubjectPublicKeyInfo  []byte // DER encoded SubjectPublicKeyInfo.
+	RawSubject               []byte // DER encoded Subject.
+
+	Version            int
+	Signature          []byte
+	SignatureAlgorithm SignatureAlgorithm
+
+	PublicKeyAlgorithm PublicKeyAlgorithm
+	PublicKey          any
+
+	Subject pkix.Name
+
+	// Attributes contains the CSR attributes that can parse as
+	// pkix.AttributeTypeAndValueSET.
+	//
+	// Deprecated: Use Extensions and ExtraExtensions instead for parsing and
+	// generating the requestedExtensions attribute.
+	Attributes []pkix.AttributeTypeAndValueSET
+
+	// Extensions contains all requested extensions, in raw form. When parsing
+	// CSRs, this can be used to extract extensions that are not parsed by this
+	// package.
+	Extensions []pkix.Extension
+
+	// ExtraExtensions contains extensions to be copied, raw, into any CSR
+	// marshaled by CreateCertificateRequest. Values override any extensions
+	// that would otherwise be produced based on the other fields but are
+	// overridden by any extensions specified in Attributes.
+	//
+	// The ExtraExtensions field is not populated by ParseCertificateRequest,
+	// see Extensions instead.
+	ExtraExtensions []pkix.Extension
+
+	// Subject Alternate Name values.
+	DNSNames       []string
+	EmailAddresses []string
+	IPAddresses    []net.IP
+	URIs           []*url.URL
+}
+
+// These structures reflect the ASN.1 structure of X.509 certificate
+// signature requests (see RFC 2986):
+
+type tbsCertificateRequest struct {
+	Raw           asn1.RawContent
+	Version       int
+	Subject       asn1.RawValue
+	PublicKey     publicKeyInfo
+	RawAttributes []asn1.RawValue `asn1:"tag:0"`
+}
+
+type certificateRequest struct {
+	Raw                asn1.RawContent
+	TBSCSR             tbsCertificateRequest
+	SignatureAlgorithm pkix.AlgorithmIdentifier
+	SignatureValue     asn1.BitString
+}
+
+// oidExtensionRequest is a PKCS #9 OBJECT IDENTIFIER that indicates requested
+// extensions in a CSR.
+var oidExtensionRequest = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 9, 14}
+
+// newRawAttributes converts AttributeTypeAndValueSETs from a template
+// CertificateRequest's Attributes into tbsCertificateRequest RawAttributes.
+func newRawAttributes(attributes []pkix.AttributeTypeAndValueSET) ([]asn1.RawValue, error) {
+	var rawAttributes []asn1.RawValue
+	b, err := asn1.Marshal(attributes)
+	if err != nil {
+		return nil, err
+	}
+	rest, err := asn1.Unmarshal(b, &rawAttributes)
+	if err != nil {
+		return nil, err
+	}
+	if len(rest) != 0 {
+		return nil, errors.New("x509: failed to unmarshal raw CSR Attributes")
+	}
+	return rawAttributes, nil
+}
+
+// parseRawAttributes Unmarshals RawAttributes into AttributeTypeAndValueSETs.
+func parseRawAttributes(rawAttributes []asn1.RawValue) []pkix.AttributeTypeAndValueSET {
+	var attributes []pkix.AttributeTypeAndValueSET
+	for _, rawAttr := range rawAttributes {
+		var attr pkix.AttributeTypeAndValueSET
+		rest, err := asn1.Unmarshal(rawAttr.FullBytes, &attr)
+		// Ignore attributes that don't parse into pkix.AttributeTypeAndValueSET
+		// (i.e.: challengePassword or unstructuredName).
+		if err == nil && len(rest) == 0 {
+			attributes = append(attributes, attr)
+		}
+	}
+	return attributes
+}
+
+// parseCSRExtensions parses the attributes from a CSR and extracts any
+// requested extensions.
+func parseCSRExtensions(rawAttributes []asn1.RawValue) ([]pkix.Extension, error) {
+	// pkcs10Attribute reflects the Attribute structure from RFC 2986, Section 4.1.
+	type pkcs10Attribute struct {
+		Id     asn1.ObjectIdentifier
+		Values []asn1.RawValue `asn1:"set"`
+	}
+
+	var ret []pkix.Extension
+	seenExts := make(map[string]bool)
+	for _, rawAttr := range rawAttributes {
+		var attr pkcs10Attribute
+		if rest, err := asn1.Unmarshal(rawAttr.FullBytes, &attr); err != nil || len(rest) != 0 || len(attr.Values) == 0 {
+			// Ignore attributes that don't parse.
+			continue
+		}
+		oidStr := attr.Id.String()
+		if seenExts[oidStr] {
+			return nil, errors.New("x509: certificate request contains duplicate extensions")
+		}
+		seenExts[oidStr] = true
+
+		if !attr.Id.Equal(oidExtensionRequest) {
+			continue
+		}
+
+		var extensions []pkix.Extension
+		if _, err := asn1.Unmarshal(attr.Values[0].FullBytes, &extensions); err != nil {
+			return nil, err
+		}
+		requestedExts := make(map[string]bool)
+		for _, ext := range extensions {
+			oidStr := ext.Id.String()
+			if requestedExts[oidStr] {
+				return nil, errors.New("x509: certificate request contains duplicate requested extensions")
+			}
+			requestedExts[oidStr] = true
+		}
+		ret = append(ret, extensions...)
+	}
+
+	return ret, nil
+}
+
+// CreateCertificateRequest creates a new certificate request based on a
+// template. The following members of template are used:
+//
+//   - SignatureAlgorithm
+//   - Subject
+//   - DNSNames
+//   - EmailAddresses
+//   - IPAddresses
+//   - URIs
+//   - ExtraExtensions
+//   - Attributes (deprecated)
+//
+// priv is the private key to sign the CSR with, and the corresponding public
+// key will be included in the CSR. It must implement crypto.Signer and its
+// Public() method must return a *rsa.PublicKey or a *ecdsa.PublicKey or a
+// ed25519.PublicKey. (A *rsa.PrivateKey, *ecdsa.PrivateKey or
+// ed25519.PrivateKey satisfies this.)
+//
+// The returned slice is the certificate request in DER encoding.
+func CreateCertificateRequest(rand io.Reader, template *CertificateRequest, priv any) (csr []byte, err error) {
+	key, ok := priv.(crypto.Signer)
+	if !ok {
+		return nil, errors.New("x509: certificate private key does not implement crypto.Signer")
+	}
+
+	var hashFunc crypto.Hash
+	var sigAlgo pkix.AlgorithmIdentifier
+	hashFunc, sigAlgo, err = signingParamsForPublicKey(key.Public(), template.SignatureAlgorithm)
+	if err != nil {
+		return nil, err
+	}
+
+	var publicKeyBytes []byte
+	var publicKeyAlgorithm pkix.AlgorithmIdentifier
+	publicKeyBytes, publicKeyAlgorithm, err = marshalPublicKey(key.Public())
+	if err != nil {
+		return nil, err
+	}
+
+	extensions, err := buildCSRExtensions(template)
+	if err != nil {
+		return nil, err
+	}
+
+	// Make a copy of template.Attributes because we may alter it below.
+	attributes := make([]pkix.AttributeTypeAndValueSET, 0, len(template.Attributes))
+	for _, attr := range template.Attributes {
+		values := make([][]pkix.AttributeTypeAndValue, len(attr.Value))
+		copy(values, attr.Value)
+		attributes = append(attributes, pkix.AttributeTypeAndValueSET{
+			Type:  attr.Type,
+			Value: values,
+		})
+	}
+
+	extensionsAppended := false
+	if len(extensions) > 0 {
+		// Append the extensions to an existing attribute if possible.
+		for _, atvSet := range attributes {
+			if !atvSet.Type.Equal(oidExtensionRequest) || len(atvSet.Value) == 0 {
+				continue
+			}
+
+			// specifiedExtensions contains all the extensions that we
+			// found specified via template.Attributes.
+			specifiedExtensions := make(map[string]bool)
+
+			for _, atvs := range atvSet.Value {
+				for _, atv := range atvs {
+					specifiedExtensions[atv.Type.String()] = true
+				}
+			}
+
+			newValue := make([]pkix.AttributeTypeAndValue, 0, len(atvSet.Value[0])+len(extensions))
+			newValue = append(newValue, atvSet.Value[0]...)
+
+			for _, e := range extensions {
+				if specifiedExtensions[e.Id.String()] {
+					// Attributes already contained a value for
+					// this extension and it takes priority.
+					continue
+				}
+
+				newValue = append(newValue, pkix.AttributeTypeAndValue{
+					// There is no place for the critical
+					// flag in an AttributeTypeAndValue.
+					Type:  e.Id,
+					Value: e.Value,
+				})
+			}
+
+			atvSet.Value[0] = newValue
+			extensionsAppended = true
+			break
+		}
+	}
+
+	rawAttributes, err := newRawAttributes(attributes)
+	if err != nil {
+		return
+	}
+
+	// If not included in attributes, add a new attribute for the
+	// extensions.
+	if len(extensions) > 0 && !extensionsAppended {
+		attr := struct {
+			Type  asn1.ObjectIdentifier
+			Value [][]pkix.Extension `asn1:"set"`
+		}{
+			Type:  oidExtensionRequest,
+			Value: [][]pkix.Extension{extensions},
+		}
+
+		b, err := asn1.Marshal(attr)
+		if err != nil {
+			return nil, errors.New("x509: failed to serialise extensions attribute: " + err.Error())
+		}
+
+		var rawValue asn1.RawValue
+		if _, err := asn1.Unmarshal(b, &rawValue); err != nil {
+			return nil, err
+		}
+
+		rawAttributes = append(rawAttributes, rawValue)
+	}
+
+	asn1Subject := template.RawSubject
+	if len(asn1Subject) == 0 {
+		asn1Subject, err = asn1.Marshal(template.Subject.ToRDNSequence())
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	tbsCSR := tbsCertificateRequest{
+		Version: 0, // PKCS #10, RFC 2986
+		Subject: asn1.RawValue{FullBytes: asn1Subject},
+		PublicKey: publicKeyInfo{
+			Algorithm: publicKeyAlgorithm,
+			PublicKey: asn1.BitString{
+				Bytes:     publicKeyBytes,
+				BitLength: len(publicKeyBytes) * 8,
+			},
+		},
+		RawAttributes: rawAttributes,
+	}
+
+	tbsCSRContents, err := asn1.Marshal(tbsCSR)
+	if err != nil {
+		return
+	}
+	tbsCSR.Raw = tbsCSRContents
+
+	signed := tbsCSRContents
+	if hashFunc != 0 {
+		h := hashFunc.New()
+		h.Write(signed)
+		signed = h.Sum(nil)
+	}
+
+	var signature []byte
+	signature, err = key.Sign(rand, signed, hashFunc)
+	if err != nil {
+		return
+	}
+
+	return asn1.Marshal(certificateRequest{
+		TBSCSR:             tbsCSR,
+		SignatureAlgorithm: sigAlgo,
+		SignatureValue: asn1.BitString{
+			Bytes:     signature,
+			BitLength: len(signature) * 8,
+		},
+	})
+}
+
+// ParseCertificateRequest parses a single certificate request from the
+// given ASN.1 DER data.
+func ParseCertificateRequest(asn1Data []byte) (*CertificateRequest, error) {
+	var csr certificateRequest
+
+	rest, err := asn1.Unmarshal(asn1Data, &csr)
+	if err != nil {
+		return nil, err
+	} else if len(rest) != 0 {
+		return nil, asn1.SyntaxError{Msg: "trailing data"}
+	}
+
+	return parseCertificateRequest(&csr)
+}
+
+func parseCertificateRequest(in *certificateRequest) (*CertificateRequest, error) {
+	out := &CertificateRequest{
+		Raw:                      in.Raw,
+		RawTBSCertificateRequest: in.TBSCSR.Raw,
+		RawSubjectPublicKeyInfo:  in.TBSCSR.PublicKey.Raw,
+		RawSubject:               in.TBSCSR.Subject.FullBytes,
+
+		Signature:          in.SignatureValue.RightAlign(),
+		SignatureAlgorithm: getSignatureAlgorithmFromAI(in.SignatureAlgorithm),
+
+		PublicKeyAlgorithm: getPublicKeyAlgorithmFromOID(in.TBSCSR.PublicKey.Algorithm.Algorithm),
+
+		Version:    in.TBSCSR.Version,
+		Attributes: parseRawAttributes(in.TBSCSR.RawAttributes),
+	}
+
+	var err error
+	out.PublicKey, err = parsePublicKey(out.PublicKeyAlgorithm, &in.TBSCSR.PublicKey)
+	if err != nil {
+		return nil, err
+	}
+
+	var subject pkix.RDNSequence
+	if rest, err := asn1.Unmarshal(in.TBSCSR.Subject.FullBytes, &subject); err != nil {
+		return nil, err
+	} else if len(rest) != 0 {
+		return nil, errors.New("x509: trailing data after X.509 Subject")
+	}
+
+	out.Subject.FillFromRDNSequence(&subject)
+
+	if out.Extensions, err = parseCSRExtensions(in.TBSCSR.RawAttributes); err != nil {
+		return nil, err
+	}
+
+	for _, extension := range out.Extensions {
+		switch {
+		case extension.Id.Equal(oidExtensionSubjectAltName):
+			out.DNSNames, out.EmailAddresses, out.IPAddresses, out.URIs, err = parseSANExtension(extension.Value)
+			if err != nil {
+				return nil, err
+			}
+		}
+	}
+
+	return out, nil
+}
+
+// CheckSignature reports whether the signature on c is valid.
+func (c *CertificateRequest) CheckSignature() error {
+	return checkSignature(c.SignatureAlgorithm, c.RawTBSCertificateRequest, c.Signature, c.PublicKey, true)
+}
+
+// RevocationList contains the fields used to create an X.509 v2 Certificate
+// Revocation list with CreateRevocationList.
+type RevocationList struct {
+	// Raw contains the complete ASN.1 DER content of the CRL (tbsCertList,
+	// signatureAlgorithm, and signatureValue.)
+	Raw []byte
+	// RawTBSRevocationList contains just the tbsCertList portion of the ASN.1
+	// DER.
+	RawTBSRevocationList []byte
+	// RawIssuer contains the DER encoded Issuer.
+	RawIssuer []byte
+
+	// Issuer contains the DN of the issuing certificate.
+	Issuer pkix.Name
+	// AuthorityKeyId is used to identify the public key associated with the
+	// issuing certificate. It is populated from the authorityKeyIdentifier
+	// extension when parsing a CRL. It is ignored when creating a CRL; the
+	// extension is populated from the issuing certificate itself.
+	AuthorityKeyId []byte
+
+	Signature []byte
+	// SignatureAlgorithm is used to determine the signature algorithm to be
+	// used when signing the CRL. If 0 the default algorithm for the signing
+	// key will be used.
+	SignatureAlgorithm SignatureAlgorithm
+
+	// RevokedCertificates is used to populate the revokedCertificates
+	// sequence in the CRL, it may be empty. RevokedCertificates may be nil,
+	// in which case an empty CRL will be created.
+	RevokedCertificates []pkix.RevokedCertificate
+
+	// Number is used to populate the X.509 v2 cRLNumber extension in the CRL,
+	// which should be a monotonically increasing sequence number for a given
+	// CRL scope and CRL issuer. It is also populated from the cRLNumber
+	// extension when parsing a CRL.
+	Number *big.Int
+
+	// ThisUpdate is used to populate the thisUpdate field in the CRL, which
+	// indicates the issuance date of the CRL.
+	ThisUpdate time.Time
+	// NextUpdate is used to populate the nextUpdate field in the CRL, which
+	// indicates the date by which the next CRL will be issued. NextUpdate
+	// must be greater than ThisUpdate.
+	NextUpdate time.Time
+
+	// Extensions contains raw X.509 extensions. When creating a CRL,
+	// the Extensions field is ignored, see ExtraExtensions.
+	Extensions []pkix.Extension
+
+	// ExtraExtensions contains any additional extensions to add directly to
+	// the CRL.
+	ExtraExtensions []pkix.Extension
+}
+
+// CreateRevocationList creates a new X.509 v2 Certificate Revocation List,
+// according to RFC 5280, based on template.
+//
+// The CRL is signed by priv which should be the private key associated with
+// the public key in the issuer certificate.
+//
+// The issuer may not be nil, and the crlSign bit must be set in KeyUsage in
+// order to use it as a CRL issuer.
+//
+// The issuer distinguished name CRL field and authority key identifier
+// extension are populated using the issuer certificate. issuer must have
+// SubjectKeyId set.
+func CreateRevocationList(rand io.Reader, template *RevocationList, issuer *Certificate, priv crypto.Signer) ([]byte, error) {
+	if template == nil {
+		return nil, errors.New("x509: template can not be nil")
+	}
+	if issuer == nil {
+		return nil, errors.New("x509: issuer can not be nil")
+	}
+	if (issuer.KeyUsage & KeyUsageCRLSign) == 0 {
+		return nil, errors.New("x509: issuer must have the crlSign key usage bit set")
+	}
+	if len(issuer.SubjectKeyId) == 0 {
+		return nil, errors.New("x509: issuer certificate doesn't contain a subject key identifier")
+	}
+	if template.NextUpdate.Before(template.ThisUpdate) {
+		return nil, errors.New("x509: template.ThisUpdate is after template.NextUpdate")
+	}
+	if template.Number == nil {
+		return nil, errors.New("x509: template contains nil Number field")
+	}
+
+	hashFunc, signatureAlgorithm, err := signingParamsForPublicKey(priv.Public(), template.SignatureAlgorithm)
+	if err != nil {
+		return nil, err
+	}
+
+	// Force revocation times to UTC per RFC 5280.
+	revokedCertsUTC := make([]pkix.RevokedCertificate, len(template.RevokedCertificates))
+	for i, rc := range template.RevokedCertificates {
+		rc.RevocationTime = rc.RevocationTime.UTC()
+		revokedCertsUTC[i] = rc
+	}
+
+	aki, err := asn1.Marshal(authKeyId{Id: issuer.SubjectKeyId})
+	if err != nil {
+		return nil, err
+	}
+
+	if numBytes := template.Number.Bytes(); len(numBytes) > 20 || (len(numBytes) == 20 && numBytes[0]&0x80 != 0) {
+		return nil, errors.New("x509: CRL number exceeds 20 octets")
+	}
+	crlNum, err := asn1.Marshal(template.Number)
+	if err != nil {
+		return nil, err
+	}
+
+	tbsCertList := pkix.TBSCertificateList{
+		Version:    1, // v2
+		Signature:  signatureAlgorithm,
+		Issuer:     issuer.Subject.ToRDNSequence(),
+		ThisUpdate: template.ThisUpdate.UTC(),
+		NextUpdate: template.NextUpdate.UTC(),
+		Extensions: []pkix.Extension{
+			{
+				Id:    oidExtensionAuthorityKeyId,
+				Value: aki,
+			},
+			{
+				Id:    oidExtensionCRLNumber,
+				Value: crlNum,
+			},
+		},
+	}
+	if len(revokedCertsUTC) > 0 {
+		tbsCertList.RevokedCertificates = revokedCertsUTC
+	}
+
+	if len(template.ExtraExtensions) > 0 {
+		tbsCertList.Extensions = append(tbsCertList.Extensions, template.ExtraExtensions...)
+	}
+
+	tbsCertListContents, err := asn1.Marshal(tbsCertList)
+	if err != nil {
+		return nil, err
+	}
+
+	input := tbsCertListContents
+	if hashFunc != 0 {
+		h := hashFunc.New()
+		h.Write(tbsCertListContents)
+		input = h.Sum(nil)
+	}
+	var signerOpts crypto.SignerOpts = hashFunc
+	if template.SignatureAlgorithm.isRSAPSS() {
+		signerOpts = &rsa.PSSOptions{
+			SaltLength: rsa.PSSSaltLengthEqualsHash,
+			Hash:       hashFunc,
+		}
+	}
+
+	signature, err := priv.Sign(rand, input, signerOpts)
+	if err != nil {
+		return nil, err
+	}
+
+	return asn1.Marshal(pkix.CertificateList{
+		TBSCertList:        tbsCertList,
+		SignatureAlgorithm: signatureAlgorithm,
+		SignatureValue:     asn1.BitString{Bytes: signature, BitLength: len(signature) * 8},
+	})
+}
+
+// CheckSignatureFrom verifies that the signature on rl is a valid signature
+// from issuer.
+func (rl *RevocationList) CheckSignatureFrom(parent *Certificate) error {
+	if parent.Version == 3 && !parent.BasicConstraintsValid ||
+		parent.BasicConstraintsValid && !parent.IsCA {
+		return ConstraintViolationError{}
+	}
+
+	if parent.KeyUsage != 0 && parent.KeyUsage&KeyUsageCRLSign == 0 {
+		return ConstraintViolationError{}
+	}
+
+	if parent.PublicKeyAlgorithm == UnknownPublicKeyAlgorithm {
+		return ErrUnsupportedAlgorithm
+	}
+
+	return parent.CheckSignature(rl.SignatureAlgorithm, rl.RawTBSRevocationList, rl.Signature)
+}
diff --git a/contrib/go/_std_1.19/src/embed/embed.go b/contrib/go/_std_1.19/src/embed/embed.go
new file mode 100644
index 0000000000..c54b961d15
--- /dev/null
+++ b/contrib/go/_std_1.19/src/embed/embed.go
@@ -0,0 +1,432 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package embed provides access to files embedded in the running Go program.
+//
+// Go source files that import "embed" can use the //go:embed directive
+// to initialize a variable of type string, []byte, or FS with the contents of
+// files read from the package directory or subdirectories at compile time.
+//
+// For example, here are three ways to embed a file named hello.txt
+// and then print its contents at run time.
+//
+// Embedding one file into a string:
+//
+//	import _ "embed"
+//
+//	//go:embed hello.txt
+//	var s string
+//	print(s)
+//
+// Embedding one file into a slice of bytes:
+//
+//	import _ "embed"
+//
+//	//go:embed hello.txt
+//	var b []byte
+//	print(string(b))
+//
+// Embedded one or more files into a file system:
+//
+//	import "embed"
+//
+//	//go:embed hello.txt
+//	var f embed.FS
+//	data, _ := f.ReadFile("hello.txt")
+//	print(string(data))
+//
+// # Directives
+//
+// A //go:embed directive above a variable declaration specifies which files to embed,
+// using one or more path.Match patterns.
+//
+// The directive must immediately precede a line containing the declaration of a single variable.
+// Only blank lines and ‘//’ line comments are permitted between the directive and the declaration.
+//
+// The type of the variable must be a string type, or a slice of a byte type,
+// or FS (or an alias of FS).
+//
+// For example:
+//
+//	package server
+//
+//	import "embed"
+//
+//	// content holds our static web server content.
+//	//go:embed image/* template/*
+//	//go:embed html/index.html
+//	var content embed.FS
+//
+// The Go build system will recognize the directives and arrange for the declared variable
+// (in the example above, content) to be populated with the matching files from the file system.
+//
+// The //go:embed directive accepts multiple space-separated patterns for
+// brevity, but it can also be repeated, to avoid very long lines when there are
+// many patterns. The patterns are interpreted relative to the package directory
+// containing the source file. The path separator is a forward slash, even on
+// Windows systems. Patterns may not contain ‘.’ or ‘..’ or empty path elements,
+// nor may they begin or end with a slash. To match everything in the current
+// directory, use ‘*’ instead of ‘.’. To allow for naming files with spaces in
+// their names, patterns can be written as Go double-quoted or back-quoted
+// string literals.
+//
+// If a pattern names a directory, all files in the subtree rooted at that directory are
+// embedded (recursively), except that files with names beginning with ‘.’ or ‘_’
+// are excluded. So the variable in the above example is almost equivalent to:
+//
+//	// content is our static web server content.
+//	//go:embed image template html/index.html
+//	var content embed.FS
+//
+// The difference is that ‘image/*’ embeds ‘image/.tempfile’ while ‘image’ does not.
+// Neither embeds ‘image/dir/.tempfile’.
+//
+// If a pattern begins with the prefix ‘all:’, then the rule for walking directories is changed
+// to include those files beginning with ‘.’ or ‘_’. For example, ‘all:image’ embeds
+// both ‘image/.tempfile’ and ‘image/dir/.tempfile’.
+//
+// The //go:embed directive can be used with both exported and unexported variables,
+// depending on whether the package wants to make the data available to other packages.
+// It can only be used with variables at package scope, not with local variables.
+//
+// Patterns must not match files outside the package's module, such as ‘.git/*’ or symbolic links.
+// Patterns must not match files whose names include the special punctuation characters  " * < > ? ` ' | / \ and :.
+// Matches for empty directories are ignored. After that, each pattern in a //go:embed line
+// must match at least one file or non-empty directory.
+//
+// If any patterns are invalid or have invalid matches, the build will fail.
+//
+// # Strings and Bytes
+//
+// The //go:embed line for a variable of type string or []byte can have only a single pattern,
+// and that pattern can match only a single file. The string or []byte is initialized with
+// the contents of that file.
+//
+// The //go:embed directive requires importing "embed", even when using a string or []byte.
+// In source files that don't refer to embed.FS, use a blank import (import _ "embed").
+//
+// # File Systems
+//
+// For embedding a single file, a variable of type string or []byte is often best.
+// The FS type enables embedding a tree of files, such as a directory of static
+// web server content, as in the example above.
+//
+// FS implements the io/fs package's FS interface, so it can be used with any package that
+// understands file systems, including net/http, text/template, and html/template.
+//
+// For example, given the content variable in the example above, we can write:
+//
+//	http.Handle("/static/", http.StripPrefix("/static/", http.FileServer(http.FS(content))))
+//
+//	template.ParseFS(content, "*.tmpl")
+//
+// # Tools
+//
+// To support tools that analyze Go packages, the patterns found in //go:embed lines
+// are available in “go list” output. See the EmbedPatterns, TestEmbedPatterns,
+// and XTestEmbedPatterns fields in the “go help list” output.
+package embed
+
+import (
+	"errors"
+	"io"
+	"io/fs"
+	"time"
+)
+
+// An FS is a read-only collection of files, usually initialized with a //go:embed directive.
+// When declared without a //go:embed directive, an FS is an empty file system.
+//
+// An FS is a read-only value, so it is safe to use from multiple goroutines
+// simultaneously and also safe to assign values of type FS to each other.
+//
+// FS implements fs.FS, so it can be used with any package that understands
+// file system interfaces, including net/http, text/template, and html/template.
+//
+// See the package documentation for more details about initializing an FS.
+type FS struct {
+	// The compiler knows the layout of this struct.
+	// See cmd/compile/internal/staticdata's WriteEmbed.
+	//
+	// The files list is sorted by name but not by simple string comparison.
+	// Instead, each file's name takes the form "dir/elem" or "dir/elem/".
+	// The optional trailing slash indicates that the file is itself a directory.
+	// The files list is sorted first by dir (if dir is missing, it is taken to be ".")
+	// and then by base, so this list of files:
+	//
+	//	p
+	//	q/
+	//	q/r
+	//	q/s/
+	//	q/s/t
+	//	q/s/u
+	//	q/v
+	//	w
+	//
+	// is actually sorted as:
+	//
+	//	p       # dir=.    elem=p
+	//	q/      # dir=.    elem=q
+	//	w/      # dir=.    elem=w
+	//	q/r     # dir=q    elem=r
+	//	q/s/    # dir=q    elem=s
+	//	q/v     # dir=q    elem=v
+	//	q/s/t   # dir=q/s  elem=t
+	//	q/s/u   # dir=q/s  elem=u
+	//
+	// This order brings directory contents together in contiguous sections
+	// of the list, allowing a directory read to use binary search to find
+	// the relevant sequence of entries.
+	files *[]file
+}
+
+// split splits the name into dir and elem as described in the
+// comment in the FS struct above. isDir reports whether the
+// final trailing slash was present, indicating that name is a directory.
+func split(name string) (dir, elem string, isDir bool) {
+	if name[len(name)-1] == '/' {
+		isDir = true
+		name = name[:len(name)-1]
+	}
+	i := len(name) - 1
+	for i >= 0 && name[i] != '/' {
+		i--
+	}
+	if i < 0 {
+		return ".", name, isDir
+	}
+	return name[:i], name[i+1:], isDir
+}
+
+// trimSlash trims a trailing slash from name, if present,
+// returning the possibly shortened name.
+func trimSlash(name string) string {
+	if len(name) > 0 && name[len(name)-1] == '/' {
+		return name[:len(name)-1]
+	}
+	return name
+}
+
+var (
+	_ fs.ReadDirFS  = FS{}
+	_ fs.ReadFileFS = FS{}
+)
+
+// A file is a single file in the FS.
+// It implements fs.FileInfo and fs.DirEntry.
+type file struct {
+	// The compiler knows the layout of this struct.
+	// See cmd/compile/internal/staticdata's WriteEmbed.
+	name string
+	data string
+	hash [16]byte // truncated SHA256 hash
+}
+
+var (
+	_ fs.FileInfo = (*file)(nil)
+	_ fs.DirEntry = (*file)(nil)
+)
+
+func (f *file) Name() string               { _, elem, _ := split(f.name); return elem }
+func (f *file) Size() int64                { return int64(len(f.data)) }
+func (f *file) ModTime() time.Time         { return time.Time{} }
+func (f *file) IsDir() bool                { _, _, isDir := split(f.name); return isDir }
+func (f *file) Sys() any                   { return nil }
+func (f *file) Type() fs.FileMode          { return f.Mode().Type() }
+func (f *file) Info() (fs.FileInfo, error) { return f, nil }
+
+func (f *file) Mode() fs.FileMode {
+	if f.IsDir() {
+		return fs.ModeDir | 0555
+	}
+	return 0444
+}
+
+// dotFile is a file for the root directory,
+// which is omitted from the files list in a FS.
+var dotFile = &file{name: "./"}
+
+// lookup returns the named file, or nil if it is not present.
+func (f FS) lookup(name string) *file {
+	if !fs.ValidPath(name) {
+		// The compiler should never emit a file with an invalid name,
+		// so this check is not strictly necessary (if name is invalid,
+		// we shouldn't find a match below), but it's a good backstop anyway.
+		return nil
+	}
+	if name == "." {
+		return dotFile
+	}
+	if f.files == nil {
+		return nil
+	}
+
+	// Binary search to find where name would be in the list,
+	// and then check if name is at that position.
+	dir, elem, _ := split(name)
+	files := *f.files
+	i := sortSearch(len(files), func(i int) bool {
+		idir, ielem, _ := split(files[i].name)
+		return idir > dir || idir == dir && ielem >= elem
+	})
+	if i < len(files) && trimSlash(files[i].name) == name {
+		return &files[i]
+	}
+	return nil
+}
+
+// readDir returns the list of files corresponding to the directory dir.
+func (f FS) readDir(dir string) []file {
+	if f.files == nil {
+		return nil
+	}
+	// Binary search to find where dir starts and ends in the list
+	// and then return that slice of the list.
+	files := *f.files
+	i := sortSearch(len(files), func(i int) bool {
+		idir, _, _ := split(files[i].name)
+		return idir >= dir
+	})
+	j := sortSearch(len(files), func(j int) bool {
+		jdir, _, _ := split(files[j].name)
+		return jdir > dir
+	})
+	return files[i:j]
+}
+
+// Open opens the named file for reading and returns it as an fs.File.
+//
+// The returned file implements io.Seeker when the file is not a directory.
+func (f FS) Open(name string) (fs.File, error) {
+	file := f.lookup(name)
+	if file == nil {
+		return nil, &fs.PathError{Op: "open", Path: name, Err: fs.ErrNotExist}
+	}
+	if file.IsDir() {
+		return &openDir{file, f.readDir(name), 0}, nil
+	}
+	return &openFile{file, 0}, nil
+}
+
+// ReadDir reads and returns the entire named directory.
+func (f FS) ReadDir(name string) ([]fs.DirEntry, error) {
+	file, err := f.Open(name)
+	if err != nil {
+		return nil, err
+	}
+	dir, ok := file.(*openDir)
+	if !ok {
+		return nil, &fs.PathError{Op: "read", Path: name, Err: errors.New("not a directory")}
+	}
+	list := make([]fs.DirEntry, len(dir.files))
+	for i := range list {
+		list[i] = &dir.files[i]
+	}
+	return list, nil
+}
+
+// ReadFile reads and returns the content of the named file.
+func (f FS) ReadFile(name string) ([]byte, error) {
+	file, err := f.Open(name)
+	if err != nil {
+		return nil, err
+	}
+	ofile, ok := file.(*openFile)
+	if !ok {
+		return nil, &fs.PathError{Op: "read", Path: name, Err: errors.New("is a directory")}
+	}
+	return []byte(ofile.f.data), nil
+}
+
+// An openFile is a regular file open for reading.
+type openFile struct {
+	f      *file // the file itself
+	offset int64 // current read offset
+}
+
+var (
+	_ io.Seeker = (*openFile)(nil)
+)
+
+func (f *openFile) Close() error               { return nil }
+func (f *openFile) Stat() (fs.FileInfo, error) { return f.f, nil }
+
+func (f *openFile) Read(b []byte) (int, error) {
+	if f.offset >= int64(len(f.f.data)) {
+		return 0, io.EOF
+	}
+	if f.offset < 0 {
+		return 0, &fs.PathError{Op: "read", Path: f.f.name, Err: fs.ErrInvalid}
+	}
+	n := copy(b, f.f.data[f.offset:])
+	f.offset += int64(n)
+	return n, nil
+}
+
+func (f *openFile) Seek(offset int64, whence int) (int64, error) {
+	switch whence {
+	case 0:
+		// offset += 0
+	case 1:
+		offset += f.offset
+	case 2:
+		offset += int64(len(f.f.data))
+	}
+	if offset < 0 || offset > int64(len(f.f.data)) {
+		return 0, &fs.PathError{Op: "seek", Path: f.f.name, Err: fs.ErrInvalid}
+	}
+	f.offset = offset
+	return offset, nil
+}
+
+// An openDir is a directory open for reading.
+type openDir struct {
+	f      *file  // the directory file itself
+	files  []file // the directory contents
+	offset int    // the read offset, an index into the files slice
+}
+
+func (d *openDir) Close() error               { return nil }
+func (d *openDir) Stat() (fs.FileInfo, error) { return d.f, nil }
+
+func (d *openDir) Read([]byte) (int, error) {
+	return 0, &fs.PathError{Op: "read", Path: d.f.name, Err: errors.New("is a directory")}
+}
+
+func (d *openDir) ReadDir(count int) ([]fs.DirEntry, error) {
+	n := len(d.files) - d.offset
+	if n == 0 {
+		if count <= 0 {
+			return nil, nil
+		}
+		return nil, io.EOF
+	}
+	if count > 0 && n > count {
+		n = count
+	}
+	list := make([]fs.DirEntry, n)
+	for i := range list {
+		list[i] = &d.files[d.offset+i]
+	}
+	d.offset += n
+	return list, nil
+}
+
+// sortSearch is like sort.Search, avoiding an import.
+func sortSearch(n int, f func(int) bool) int {
+	// Define f(-1) == false and f(n) == true.
+	// Invariant: f(i-1) == false, f(j) == true.
+	i, j := 0, n
+	for i < j {
+		h := int(uint(i+j) >> 1) // avoid overflow when computing h
+		// i ≤ h < j
+		if !f(h) {
+			i = h + 1 // preserves f(i-1) == false
+		} else {
+			j = h // preserves f(j) == true
+		}
+	}
+	// i == j, f(i-1) == false, and f(j) (= f(i)) == true  =>  answer is i.
+	return i
+}
diff --git a/contrib/go/_std_1.19/src/encoding/asn1/asn1.go b/contrib/go/_std_1.19/src/encoding/asn1/asn1.go
new file mode 100644
index 0000000000..c90bba47dc
--- /dev/null
+++ b/contrib/go/_std_1.19/src/encoding/asn1/asn1.go
@@ -0,0 +1,1122 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package asn1 implements parsing of DER-encoded ASN.1 data structures,
+// as defined in ITU-T Rec X.690.
+//
+// See also “A Layman's Guide to a Subset of ASN.1, BER, and DER,”
+// http://luca.ntop.org/Teaching/Appunti/asn1.html.
+package asn1
+
+// ASN.1 is a syntax for specifying abstract objects and BER, DER, PER, XER etc
+// are different encoding formats for those objects. Here, we'll be dealing
+// with DER, the Distinguished Encoding Rules. DER is used in X.509 because
+// it's fast to parse and, unlike BER, has a unique encoding for every object.
+// When calculating hashes over objects, it's important that the resulting
+// bytes be the same at both ends and DER removes this margin of error.
+//
+// ASN.1 is very complex and this package doesn't attempt to implement
+// everything by any means.
+
+import (
+	"errors"
+	"fmt"
+	"math"
+	"math/big"
+	"reflect"
+	"strconv"
+	"time"
+	"unicode/utf16"
+	"unicode/utf8"
+)
+
+// A StructuralError suggests that the ASN.1 data is valid, but the Go type
+// which is receiving it doesn't match.
+type StructuralError struct {
+	Msg string
+}
+
+func (e StructuralError) Error() string { return "asn1: structure error: " + e.Msg }
+
+// A SyntaxError suggests that the ASN.1 data is invalid.
+type SyntaxError struct {
+	Msg string
+}
+
+func (e SyntaxError) Error() string { return "asn1: syntax error: " + e.Msg }
+
+// We start by dealing with each of the primitive types in turn.
+
+// BOOLEAN
+
+func parseBool(bytes []byte) (ret bool, err error) {
+	if len(bytes) != 1 {
+		err = SyntaxError{"invalid boolean"}
+		return
+	}
+
+	// DER demands that "If the encoding represents the boolean value TRUE,
+	// its single contents octet shall have all eight bits set to one."
+	// Thus only 0 and 255 are valid encoded values.
+	switch bytes[0] {
+	case 0:
+		ret = false
+	case 0xff:
+		ret = true
+	default:
+		err = SyntaxError{"invalid boolean"}
+	}
+
+	return
+}
+
+// INTEGER
+
+// checkInteger returns nil if the given bytes are a valid DER-encoded
+// INTEGER and an error otherwise.
+func checkInteger(bytes []byte) error {
+	if len(bytes) == 0 {
+		return StructuralError{"empty integer"}
+	}
+	if len(bytes) == 1 {
+		return nil
+	}
+	if (bytes[0] == 0 && bytes[1]&0x80 == 0) || (bytes[0] == 0xff && bytes[1]&0x80 == 0x80) {
+		return StructuralError{"integer not minimally-encoded"}
+	}
+	return nil
+}
+
+// parseInt64 treats the given bytes as a big-endian, signed integer and
+// returns the result.
+func parseInt64(bytes []byte) (ret int64, err error) {
+	err = checkInteger(bytes)
+	if err != nil {
+		return
+	}
+	if len(bytes) > 8 {
+		// We'll overflow an int64 in this case.
+		err = StructuralError{"integer too large"}
+		return
+	}
+	for bytesRead := 0; bytesRead < len(bytes); bytesRead++ {
+		ret <<= 8
+		ret |= int64(bytes[bytesRead])
+	}
+
+	// Shift up and down in order to sign extend the result.
+	ret <<= 64 - uint8(len(bytes))*8
+	ret >>= 64 - uint8(len(bytes))*8
+	return
+}
+
+// parseInt treats the given bytes as a big-endian, signed integer and returns
+// the result.
+func parseInt32(bytes []byte) (int32, error) {
+	if err := checkInteger(bytes); err != nil {
+		return 0, err
+	}
+	ret64, err := parseInt64(bytes)
+	if err != nil {
+		return 0, err
+	}
+	if ret64 != int64(int32(ret64)) {
+		return 0, StructuralError{"integer too large"}
+	}
+	return int32(ret64), nil
+}
+
+var bigOne = big.NewInt(1)
+
+// parseBigInt treats the given bytes as a big-endian, signed integer and returns
+// the result.
+func parseBigInt(bytes []byte) (*big.Int, error) {
+	if err := checkInteger(bytes); err != nil {
+		return nil, err
+	}
+	ret := new(big.Int)
+	if len(bytes) > 0 && bytes[0]&0x80 == 0x80 {
+		// This is a negative number.
+		notBytes := make([]byte, len(bytes))
+		for i := range notBytes {
+			notBytes[i] = ^bytes[i]
+		}
+		ret.SetBytes(notBytes)
+		ret.Add(ret, bigOne)
+		ret.Neg(ret)
+		return ret, nil
+	}
+	ret.SetBytes(bytes)
+	return ret, nil
+}
+
+// BIT STRING
+
+// BitString is the structure to use when you want an ASN.1 BIT STRING type. A
+// bit string is padded up to the nearest byte in memory and the number of
+// valid bits is recorded. Padding bits will be zero.
+type BitString struct {
+	Bytes     []byte // bits packed into bytes.
+	BitLength int    // length in bits.
+}
+
+// At returns the bit at the given index. If the index is out of range it
+// returns false.
+func (b BitString) At(i int) int {
+	if i < 0 || i >= b.BitLength {
+		return 0
+	}
+	x := i / 8
+	y := 7 - uint(i%8)
+	return int(b.Bytes[x]>>y) & 1
+}
+
+// RightAlign returns a slice where the padding bits are at the beginning. The
+// slice may share memory with the BitString.
+func (b BitString) RightAlign() []byte {
+	shift := uint(8 - (b.BitLength % 8))
+	if shift == 8 || len(b.Bytes) == 0 {
+		return b.Bytes
+	}
+
+	a := make([]byte, len(b.Bytes))
+	a[0] = b.Bytes[0] >> shift
+	for i := 1; i < len(b.Bytes); i++ {
+		a[i] = b.Bytes[i-1] << (8 - shift)
+		a[i] |= b.Bytes[i] >> shift
+	}
+
+	return a
+}
+
+// parseBitString parses an ASN.1 bit string from the given byte slice and returns it.
+func parseBitString(bytes []byte) (ret BitString, err error) {
+	if len(bytes) == 0 {
+		err = SyntaxError{"zero length BIT STRING"}
+		return
+	}
+	paddingBits := int(bytes[0])
+	if paddingBits > 7 ||
+		len(bytes) == 1 && paddingBits > 0 ||
+		bytes[len(bytes)-1]&((1<<bytes[0])-1) != 0 {
+		err = SyntaxError{"invalid padding bits in BIT STRING"}
+		return
+	}
+	ret.BitLength = (len(bytes)-1)*8 - paddingBits
+	ret.Bytes = bytes[1:]
+	return
+}
+
+// NULL
+
+// NullRawValue is a RawValue with its Tag set to the ASN.1 NULL type tag (5).
+var NullRawValue = RawValue{Tag: TagNull}
+
+// NullBytes contains bytes representing the DER-encoded ASN.1 NULL type.
+var NullBytes = []byte{TagNull, 0}
+
+// OBJECT IDENTIFIER
+
+// An ObjectIdentifier represents an ASN.1 OBJECT IDENTIFIER.
+type ObjectIdentifier []int
+
+// Equal reports whether oi and other represent the same identifier.
+func (oi ObjectIdentifier) Equal(other ObjectIdentifier) bool {
+	if len(oi) != len(other) {
+		return false
+	}
+	for i := 0; i < len(oi); i++ {
+		if oi[i] != other[i] {
+			return false
+		}
+	}
+
+	return true
+}
+
+func (oi ObjectIdentifier) String() string {
+	var s string
+
+	for i, v := range oi {
+		if i > 0 {
+			s += "."
+		}
+		s += strconv.Itoa(v)
+	}
+
+	return s
+}
+
+// parseObjectIdentifier parses an OBJECT IDENTIFIER from the given bytes and
+// returns it. An object identifier is a sequence of variable length integers
+// that are assigned in a hierarchy.
+func parseObjectIdentifier(bytes []byte) (s ObjectIdentifier, err error) {
+	if len(bytes) == 0 {
+		err = SyntaxError{"zero length OBJECT IDENTIFIER"}
+		return
+	}
+
+	// In the worst case, we get two elements from the first byte (which is
+	// encoded differently) and then every varint is a single byte long.
+	s = make([]int, len(bytes)+1)
+
+	// The first varint is 40*value1 + value2:
+	// According to this packing, value1 can take the values 0, 1 and 2 only.
+	// When value1 = 0 or value1 = 1, then value2 is <= 39. When value1 = 2,
+	// then there are no restrictions on value2.
+	v, offset, err := parseBase128Int(bytes, 0)
+	if err != nil {
+		return
+	}
+	if v < 80 {
+		s[0] = v / 40
+		s[1] = v % 40
+	} else {
+		s[0] = 2
+		s[1] = v - 80
+	}
+
+	i := 2
+	for ; offset < len(bytes); i++ {
+		v, offset, err = parseBase128Int(bytes, offset)
+		if err != nil {
+			return
+		}
+		s[i] = v
+	}
+	s = s[0:i]
+	return
+}
+
+// ENUMERATED
+
+// An Enumerated is represented as a plain int.
+type Enumerated int
+
+// FLAG
+
+// A Flag accepts any data and is set to true if present.
+type Flag bool
+
+// parseBase128Int parses a base-128 encoded int from the given offset in the
+// given byte slice. It returns the value and the new offset.
+func parseBase128Int(bytes []byte, initOffset int) (ret, offset int, err error) {
+	offset = initOffset
+	var ret64 int64
+	for shifted := 0; offset < len(bytes); shifted++ {
+		// 5 * 7 bits per byte == 35 bits of data
+		// Thus the representation is either non-minimal or too large for an int32
+		if shifted == 5 {
+			err = StructuralError{"base 128 integer too large"}
+			return
+		}
+		ret64 <<= 7
+		b := bytes[offset]
+		// integers should be minimally encoded, so the leading octet should
+		// never be 0x80
+		if shifted == 0 && b == 0x80 {
+			err = SyntaxError{"integer is not minimally encoded"}
+			return
+		}
+		ret64 |= int64(b & 0x7f)
+		offset++
+		if b&0x80 == 0 {
+			ret = int(ret64)
+			// Ensure that the returned value fits in an int on all platforms
+			if ret64 > math.MaxInt32 {
+				err = StructuralError{"base 128 integer too large"}
+			}
+			return
+		}
+	}
+	err = SyntaxError{"truncated base 128 integer"}
+	return
+}
+
+// UTCTime
+
+func parseUTCTime(bytes []byte) (ret time.Time, err error) {
+	s := string(bytes)
+
+	formatStr := "0601021504Z0700"
+	ret, err = time.Parse(formatStr, s)
+	if err != nil {
+		formatStr = "060102150405Z0700"
+		ret, err = time.Parse(formatStr, s)
+	}
+	if err != nil {
+		return
+	}
+
+	if serialized := ret.Format(formatStr); serialized != s {
+		err = fmt.Errorf("asn1: time did not serialize back to the original value and may be invalid: given %q, but serialized as %q", s, serialized)
+		return
+	}
+
+	if ret.Year() >= 2050 {
+		// UTCTime only encodes times prior to 2050. See https://tools.ietf.org/html/rfc5280#section-4.1.2.5.1
+		ret = ret.AddDate(-100, 0, 0)
+	}
+
+	return
+}
+
+// parseGeneralizedTime parses the GeneralizedTime from the given byte slice
+// and returns the resulting time.
+func parseGeneralizedTime(bytes []byte) (ret time.Time, err error) {
+	const formatStr = "20060102150405Z0700"
+	s := string(bytes)
+
+	if ret, err = time.Parse(formatStr, s); err != nil {
+		return
+	}
+
+	if serialized := ret.Format(formatStr); serialized != s {
+		err = fmt.Errorf("asn1: time did not serialize back to the original value and may be invalid: given %q, but serialized as %q", s, serialized)
+	}
+
+	return
+}
+
+// NumericString
+
+// parseNumericString parses an ASN.1 NumericString from the given byte array
+// and returns it.
+func parseNumericString(bytes []byte) (ret string, err error) {
+	for _, b := range bytes {
+		if !isNumeric(b) {
+			return "", SyntaxError{"NumericString contains invalid character"}
+		}
+	}
+	return string(bytes), nil
+}
+
+// isNumeric reports whether the given b is in the ASN.1 NumericString set.
+func isNumeric(b byte) bool {
+	return '0' <= b && b <= '9' ||
+		b == ' '
+}
+
+// PrintableString
+
+// parsePrintableString parses an ASN.1 PrintableString from the given byte
+// array and returns it.
+func parsePrintableString(bytes []byte) (ret string, err error) {
+	for _, b := range bytes {
+		if !isPrintable(b, allowAsterisk, allowAmpersand) {
+			err = SyntaxError{"PrintableString contains invalid character"}
+			return
+		}
+	}
+	ret = string(bytes)
+	return
+}
+
+type asteriskFlag bool
+type ampersandFlag bool
+
+const (
+	allowAsterisk  asteriskFlag = true
+	rejectAsterisk asteriskFlag = false
+
+	allowAmpersand  ampersandFlag = true
+	rejectAmpersand ampersandFlag = false
+)
+
+// isPrintable reports whether the given b is in the ASN.1 PrintableString set.
+// If asterisk is allowAsterisk then '*' is also allowed, reflecting existing
+// practice. If ampersand is allowAmpersand then '&' is allowed as well.
+func isPrintable(b byte, asterisk asteriskFlag, ampersand ampersandFlag) bool {
+	return 'a' <= b && b <= 'z' ||
+		'A' <= b && b <= 'Z' ||
+		'0' <= b && b <= '9' ||
+		'\'' <= b && b <= ')' ||
+		'+' <= b && b <= '/' ||
+		b == ' ' ||
+		b == ':' ||
+		b == '=' ||
+		b == '?' ||
+		// This is technically not allowed in a PrintableString.
+		// However, x509 certificates with wildcard strings don't
+		// always use the correct string type so we permit it.
+		(bool(asterisk) && b == '*') ||
+		// This is not technically allowed either. However, not
+		// only is it relatively common, but there are also a
+		// handful of CA certificates that contain it. At least
+		// one of which will not expire until 2027.
+		(bool(ampersand) && b == '&')
+}
+
+// IA5String
+
+// parseIA5String parses an ASN.1 IA5String (ASCII string) from the given
+// byte slice and returns it.
+func parseIA5String(bytes []byte) (ret string, err error) {
+	for _, b := range bytes {
+		if b >= utf8.RuneSelf {
+			err = SyntaxError{"IA5String contains invalid character"}
+			return
+		}
+	}
+	ret = string(bytes)
+	return
+}
+
+// T61String
+
+// parseT61String parses an ASN.1 T61String (8-bit clean string) from the given
+// byte slice and returns it.
+func parseT61String(bytes []byte) (ret string, err error) {
+	return string(bytes), nil
+}
+
+// UTF8String
+
+// parseUTF8String parses an ASN.1 UTF8String (raw UTF-8) from the given byte
+// array and returns it.
+func parseUTF8String(bytes []byte) (ret string, err error) {
+	if !utf8.Valid(bytes) {
+		return "", errors.New("asn1: invalid UTF-8 string")
+	}
+	return string(bytes), nil
+}
+
+// BMPString
+
+// parseBMPString parses an ASN.1 BMPString (Basic Multilingual Plane of
+// ISO/IEC/ITU 10646-1) from the given byte slice and returns it.
+func parseBMPString(bmpString []byte) (string, error) {
+	if len(bmpString)%2 != 0 {
+		return "", errors.New("pkcs12: odd-length BMP string")
+	}
+
+	// Strip terminator if present.
+	if l := len(bmpString); l >= 2 && bmpString[l-1] == 0 && bmpString[l-2] == 0 {
+		bmpString = bmpString[:l-2]
+	}
+
+	s := make([]uint16, 0, len(bmpString)/2)
+	for len(bmpString) > 0 {
+		s = append(s, uint16(bmpString[0])<<8+uint16(bmpString[1]))
+		bmpString = bmpString[2:]
+	}
+
+	return string(utf16.Decode(s)), nil
+}
+
+// A RawValue represents an undecoded ASN.1 object.
+type RawValue struct {
+	Class, Tag int
+	IsCompound bool
+	Bytes      []byte
+	FullBytes  []byte // includes the tag and length
+}
+
+// RawContent is used to signal that the undecoded, DER data needs to be
+// preserved for a struct. To use it, the first field of the struct must have
+// this type. It's an error for any of the other fields to have this type.
+type RawContent []byte
+
+// Tagging
+
+// parseTagAndLength parses an ASN.1 tag and length pair from the given offset
+// into a byte slice. It returns the parsed data and the new offset. SET and
+// SET OF (tag 17) are mapped to SEQUENCE and SEQUENCE OF (tag 16) since we
+// don't distinguish between ordered and unordered objects in this code.
+func parseTagAndLength(bytes []byte, initOffset int) (ret tagAndLength, offset int, err error) {
+	offset = initOffset
+	// parseTagAndLength should not be called without at least a single
+	// byte to read. Thus this check is for robustness:
+	if offset >= len(bytes) {
+		err = errors.New("asn1: internal error in parseTagAndLength")
+		return
+	}
+	b := bytes[offset]
+	offset++
+	ret.class = int(b >> 6)
+	ret.isCompound = b&0x20 == 0x20
+	ret.tag = int(b & 0x1f)
+
+	// If the bottom five bits are set, then the tag number is actually base 128
+	// encoded afterwards
+	if ret.tag == 0x1f {
+		ret.tag, offset, err = parseBase128Int(bytes, offset)
+		if err != nil {
+			return
+		}
+		// Tags should be encoded in minimal form.
+		if ret.tag < 0x1f {
+			err = SyntaxError{"non-minimal tag"}
+			return
+		}
+	}
+	if offset >= len(bytes) {
+		err = SyntaxError{"truncated tag or length"}
+		return
+	}
+	b = bytes[offset]
+	offset++
+	if b&0x80 == 0 {
+		// The length is encoded in the bottom 7 bits.
+		ret.length = int(b & 0x7f)
+	} else {
+		// Bottom 7 bits give the number of length bytes to follow.
+		numBytes := int(b & 0x7f)
+		if numBytes == 0 {
+			err = SyntaxError{"indefinite length found (not DER)"}
+			return
+		}
+		ret.length = 0
+		for i := 0; i < numBytes; i++ {
+			if offset >= len(bytes) {
+				err = SyntaxError{"truncated tag or length"}
+				return
+			}
+			b = bytes[offset]
+			offset++
+			if ret.length >= 1<<23 {
+				// We can't shift ret.length up without
+				// overflowing.
+				err = StructuralError{"length too large"}
+				return
+			}
+			ret.length <<= 8
+			ret.length |= int(b)
+			if ret.length == 0 {
+				// DER requires that lengths be minimal.
+				err = StructuralError{"superfluous leading zeros in length"}
+				return
+			}
+		}
+		// Short lengths must be encoded in short form.
+		if ret.length < 0x80 {
+			err = StructuralError{"non-minimal length"}
+			return
+		}
+	}
+
+	return
+}
+
+// parseSequenceOf is used for SEQUENCE OF and SET OF values. It tries to parse
+// a number of ASN.1 values from the given byte slice and returns them as a
+// slice of Go values of the given type.
+func parseSequenceOf(bytes []byte, sliceType reflect.Type, elemType reflect.Type) (ret reflect.Value, err error) {
+	matchAny, expectedTag, compoundType, ok := getUniversalType(elemType)
+	if !ok {
+		err = StructuralError{"unknown Go type for slice"}
+		return
+	}
+
+	// First we iterate over the input and count the number of elements,
+	// checking that the types are correct in each case.
+	numElements := 0
+	for offset := 0; offset < len(bytes); {
+		var t tagAndLength
+		t, offset, err = parseTagAndLength(bytes, offset)
+		if err != nil {
+			return
+		}
+		switch t.tag {
+		case TagIA5String, TagGeneralString, TagT61String, TagUTF8String, TagNumericString, TagBMPString:
+			// We pretend that various other string types are
+			// PRINTABLE STRINGs so that a sequence of them can be
+			// parsed into a []string.
+			t.tag = TagPrintableString
+		case TagGeneralizedTime, TagUTCTime:
+			// Likewise, both time types are treated the same.
+			t.tag = TagUTCTime
+		}
+
+		if !matchAny && (t.class != ClassUniversal || t.isCompound != compoundType || t.tag != expectedTag) {
+			err = StructuralError{"sequence tag mismatch"}
+			return
+		}
+		if invalidLength(offset, t.length, len(bytes)) {
+			err = SyntaxError{"truncated sequence"}
+			return
+		}
+		offset += t.length
+		numElements++
+	}
+	ret = reflect.MakeSlice(sliceType, numElements, numElements)
+	params := fieldParameters{}
+	offset := 0
+	for i := 0; i < numElements; i++ {
+		offset, err = parseField(ret.Index(i), bytes, offset, params)
+		if err != nil {
+			return
+		}
+	}
+	return
+}
+
+var (
+	bitStringType        = reflect.TypeOf(BitString{})
+	objectIdentifierType = reflect.TypeOf(ObjectIdentifier{})
+	enumeratedType       = reflect.TypeOf(Enumerated(0))
+	flagType             = reflect.TypeOf(Flag(false))
+	timeType             = reflect.TypeOf(time.Time{})
+	rawValueType         = reflect.TypeOf(RawValue{})
+	rawContentsType      = reflect.TypeOf(RawContent(nil))
+	bigIntType           = reflect.TypeOf(new(big.Int))
+)
+
+// invalidLength reports whether offset + length > sliceLength, or if the
+// addition would overflow.
+func invalidLength(offset, length, sliceLength int) bool {
+	return offset+length < offset || offset+length > sliceLength
+}
+
+// parseField is the main parsing function. Given a byte slice and an offset
+// into the array, it will try to parse a suitable ASN.1 value out and store it
+// in the given Value.
+func parseField(v reflect.Value, bytes []byte, initOffset int, params fieldParameters) (offset int, err error) {
+	offset = initOffset
+	fieldType := v.Type()
+
+	// If we have run out of data, it may be that there are optional elements at the end.
+	if offset == len(bytes) {
+		if !setDefaultValue(v, params) {
+			err = SyntaxError{"sequence truncated"}
+		}
+		return
+	}
+
+	// Deal with the ANY type.
+	if ifaceType := fieldType; ifaceType.Kind() == reflect.Interface && ifaceType.NumMethod() == 0 {
+		var t tagAndLength
+		t, offset, err = parseTagAndLength(bytes, offset)
+		if err != nil {
+			return
+		}
+		if invalidLength(offset, t.length, len(bytes)) {
+			err = SyntaxError{"data truncated"}
+			return
+		}
+		var result any
+		if !t.isCompound && t.class == ClassUniversal {
+			innerBytes := bytes[offset : offset+t.length]
+			switch t.tag {
+			case TagPrintableString:
+				result, err = parsePrintableString(innerBytes)
+			case TagNumericString:
+				result, err = parseNumericString(innerBytes)
+			case TagIA5String:
+				result, err = parseIA5String(innerBytes)
+			case TagT61String:
+				result, err = parseT61String(innerBytes)
+			case TagUTF8String:
+				result, err = parseUTF8String(innerBytes)
+			case TagInteger:
+				result, err = parseInt64(innerBytes)
+			case TagBitString:
+				result, err = parseBitString(innerBytes)
+			case TagOID:
+				result, err = parseObjectIdentifier(innerBytes)
+			case TagUTCTime:
+				result, err = parseUTCTime(innerBytes)
+			case TagGeneralizedTime:
+				result, err = parseGeneralizedTime(innerBytes)
+			case TagOctetString:
+				result = innerBytes
+			case TagBMPString:
+				result, err = parseBMPString(innerBytes)
+			default:
+				// If we don't know how to handle the type, we just leave Value as nil.
+			}
+		}
+		offset += t.length
+		if err != nil {
+			return
+		}
+		if result != nil {
+			v.Set(reflect.ValueOf(result))
+		}
+		return
+	}
+
+	t, offset, err := parseTagAndLength(bytes, offset)
+	if err != nil {
+		return
+	}
+	if params.explicit {
+		expectedClass := ClassContextSpecific
+		if params.application {
+			expectedClass = ClassApplication
+		}
+		if offset == len(bytes) {
+			err = StructuralError{"explicit tag has no child"}
+			return
+		}
+		if t.class == expectedClass && t.tag == *params.tag && (t.length == 0 || t.isCompound) {
+			if fieldType == rawValueType {
+				// The inner element should not be parsed for RawValues.
+			} else if t.length > 0 {
+				t, offset, err = parseTagAndLength(bytes, offset)
+				if err != nil {
+					return
+				}
+			} else {
+				if fieldType != flagType {
+					err = StructuralError{"zero length explicit tag was not an asn1.Flag"}
+					return
+				}
+				v.SetBool(true)
+				return
+			}
+		} else {
+			// The tags didn't match, it might be an optional element.
+			ok := setDefaultValue(v, params)
+			if ok {
+				offset = initOffset
+			} else {
+				err = StructuralError{"explicitly tagged member didn't match"}
+			}
+			return
+		}
+	}
+
+	matchAny, universalTag, compoundType, ok1 := getUniversalType(fieldType)
+	if !ok1 {
+		err = StructuralError{fmt.Sprintf("unknown Go type: %v", fieldType)}
+		return
+	}
+
+	// Special case for strings: all the ASN.1 string types map to the Go
+	// type string. getUniversalType returns the tag for PrintableString
+	// when it sees a string, so if we see a different string type on the
+	// wire, we change the universal type to match.
+	if universalTag == TagPrintableString {
+		if t.class == ClassUniversal {
+			switch t.tag {
+			case TagIA5String, TagGeneralString, TagT61String, TagUTF8String, TagNumericString, TagBMPString:
+				universalTag = t.tag
+			}
+		} else if params.stringType != 0 {
+			universalTag = params.stringType
+		}
+	}
+
+	// Special case for time: UTCTime and GeneralizedTime both map to the
+	// Go type time.Time.
+	if universalTag == TagUTCTime && t.tag == TagGeneralizedTime && t.class == ClassUniversal {
+		universalTag = TagGeneralizedTime
+	}
+
+	if params.set {
+		universalTag = TagSet
+	}
+
+	matchAnyClassAndTag := matchAny
+	expectedClass := ClassUniversal
+	expectedTag := universalTag
+
+	if !params.explicit && params.tag != nil {
+		expectedClass = ClassContextSpecific
+		expectedTag = *params.tag
+		matchAnyClassAndTag = false
+	}
+
+	if !params.explicit && params.application && params.tag != nil {
+		expectedClass = ClassApplication
+		expectedTag = *params.tag
+		matchAnyClassAndTag = false
+	}
+
+	if !params.explicit && params.private && params.tag != nil {
+		expectedClass = ClassPrivate
+		expectedTag = *params.tag
+		matchAnyClassAndTag = false
+	}
+
+	// We have unwrapped any explicit tagging at this point.
+	if !matchAnyClassAndTag && (t.class != expectedClass || t.tag != expectedTag) ||
+		(!matchAny && t.isCompound != compoundType) {
+		// Tags don't match. Again, it could be an optional element.
+		ok := setDefaultValue(v, params)
+		if ok {
+			offset = initOffset
+		} else {
+			err = StructuralError{fmt.Sprintf("tags don't match (%d vs %+v) %+v %s @%d", expectedTag, t, params, fieldType.Name(), offset)}
+		}
+		return
+	}
+	if invalidLength(offset, t.length, len(bytes)) {
+		err = SyntaxError{"data truncated"}
+		return
+	}
+	innerBytes := bytes[offset : offset+t.length]
+	offset += t.length
+
+	// We deal with the structures defined in this package first.
+	switch v := v.Addr().Interface().(type) {
+	case *RawValue:
+		*v = RawValue{t.class, t.tag, t.isCompound, innerBytes, bytes[initOffset:offset]}
+		return
+	case *ObjectIdentifier:
+		*v, err = parseObjectIdentifier(innerBytes)
+		return
+	case *BitString:
+		*v, err = parseBitString(innerBytes)
+		return
+	case *time.Time:
+		if universalTag == TagUTCTime {
+			*v, err = parseUTCTime(innerBytes)
+			return
+		}
+		*v, err = parseGeneralizedTime(innerBytes)
+		return
+	case *Enumerated:
+		parsedInt, err1 := parseInt32(innerBytes)
+		if err1 == nil {
+			*v = Enumerated(parsedInt)
+		}
+		err = err1
+		return
+	case *Flag:
+		*v = true
+		return
+	case **big.Int:
+		parsedInt, err1 := parseBigInt(innerBytes)
+		if err1 == nil {
+			*v = parsedInt
+		}
+		err = err1
+		return
+	}
+	switch val := v; val.Kind() {
+	case reflect.Bool:
+		parsedBool, err1 := parseBool(innerBytes)
+		if err1 == nil {
+			val.SetBool(parsedBool)
+		}
+		err = err1
+		return
+	case reflect.Int, reflect.Int32, reflect.Int64:
+		if val.Type().Size() == 4 {
+			parsedInt, err1 := parseInt32(innerBytes)
+			if err1 == nil {
+				val.SetInt(int64(parsedInt))
+			}
+			err = err1
+		} else {
+			parsedInt, err1 := parseInt64(innerBytes)
+			if err1 == nil {
+				val.SetInt(parsedInt)
+			}
+			err = err1
+		}
+		return
+	// TODO(dfc) Add support for the remaining integer types
+	case reflect.Struct:
+		structType := fieldType
+
+		for i := 0; i < structType.NumField(); i++ {
+			if !structType.Field(i).IsExported() {
+				err = StructuralError{"struct contains unexported fields"}
+				return
+			}
+		}
+
+		if structType.NumField() > 0 &&
+			structType.Field(0).Type == rawContentsType {
+			bytes := bytes[initOffset:offset]
+			val.Field(0).Set(reflect.ValueOf(RawContent(bytes)))
+		}
+
+		innerOffset := 0
+		for i := 0; i < structType.NumField(); i++ {
+			field := structType.Field(i)
+			if i == 0 && field.Type == rawContentsType {
+				continue
+			}
+			innerOffset, err = parseField(val.Field(i), innerBytes, innerOffset, parseFieldParameters(field.Tag.Get("asn1")))
+			if err != nil {
+				return
+			}
+		}
+		// We allow extra bytes at the end of the SEQUENCE because
+		// adding elements to the end has been used in X.509 as the
+		// version numbers have increased.
+		return
+	case reflect.Slice:
+		sliceType := fieldType
+		if sliceType.Elem().Kind() == reflect.Uint8 {
+			val.Set(reflect.MakeSlice(sliceType, len(innerBytes), len(innerBytes)))
+			reflect.Copy(val, reflect.ValueOf(innerBytes))
+			return
+		}
+		newSlice, err1 := parseSequenceOf(innerBytes, sliceType, sliceType.Elem())
+		if err1 == nil {
+			val.Set(newSlice)
+		}
+		err = err1
+		return
+	case reflect.String:
+		var v string
+		switch universalTag {
+		case TagPrintableString:
+			v, err = parsePrintableString(innerBytes)
+		case TagNumericString:
+			v, err = parseNumericString(innerBytes)
+		case TagIA5String:
+			v, err = parseIA5String(innerBytes)
+		case TagT61String:
+			v, err = parseT61String(innerBytes)
+		case TagUTF8String:
+			v, err = parseUTF8String(innerBytes)
+		case TagGeneralString:
+			// GeneralString is specified in ISO-2022/ECMA-35,
+			// A brief review suggests that it includes structures
+			// that allow the encoding to change midstring and
+			// such. We give up and pass it as an 8-bit string.
+			v, err = parseT61String(innerBytes)
+		case TagBMPString:
+			v, err = parseBMPString(innerBytes)
+
+		default:
+			err = SyntaxError{fmt.Sprintf("internal error: unknown string type %d", universalTag)}
+		}
+		if err == nil {
+			val.SetString(v)
+		}
+		return
+	}
+	err = StructuralError{"unsupported: " + v.Type().String()}
+	return
+}
+
+// canHaveDefaultValue reports whether k is a Kind that we will set a default
+// value for. (A signed integer, essentially.)
+func canHaveDefaultValue(k reflect.Kind) bool {
+	switch k {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return true
+	}
+
+	return false
+}
+
+// setDefaultValue is used to install a default value, from a tag string, into
+// a Value. It is successful if the field was optional, even if a default value
+// wasn't provided or it failed to install it into the Value.
+func setDefaultValue(v reflect.Value, params fieldParameters) (ok bool) {
+	if !params.optional {
+		return
+	}
+	ok = true
+	if params.defaultValue == nil {
+		return
+	}
+	if canHaveDefaultValue(v.Kind()) {
+		v.SetInt(*params.defaultValue)
+	}
+	return
+}
+
+// Unmarshal parses the DER-encoded ASN.1 data structure b
+// and uses the reflect package to fill in an arbitrary value pointed at by val.
+// Because Unmarshal uses the reflect package, the structs
+// being written to must use upper case field names. If val
+// is nil or not a pointer, Unmarshal returns an error.
+//
+// After parsing b, any bytes that were leftover and not used to fill
+// val will be returned in rest. When parsing a SEQUENCE into a struct,
+// any trailing elements of the SEQUENCE that do not have matching
+// fields in val will not be included in rest, as these are considered
+// valid elements of the SEQUENCE and not trailing data.
+//
+// An ASN.1 INTEGER can be written to an int, int32, int64,
+// or *big.Int (from the math/big package).
+// If the encoded value does not fit in the Go type,
+// Unmarshal returns a parse error.
+//
+// An ASN.1 BIT STRING can be written to a BitString.
+//
+// An ASN.1 OCTET STRING can be written to a []byte.
+//
+// An ASN.1 OBJECT IDENTIFIER can be written to an
+// ObjectIdentifier.
+//
+// An ASN.1 ENUMERATED can be written to an Enumerated.
+//
+// An ASN.1 UTCTIME or GENERALIZEDTIME can be written to a time.Time.
+//
+// An ASN.1 PrintableString, IA5String, or NumericString can be written to a string.
+//
+// Any of the above ASN.1 values can be written to an interface{}.
+// The value stored in the interface has the corresponding Go type.
+// For integers, that type is int64.
+//
+// An ASN.1 SEQUENCE OF x or SET OF x can be written
+// to a slice if an x can be written to the slice's element type.
+//
+// An ASN.1 SEQUENCE or SET can be written to a struct
+// if each of the elements in the sequence can be
+// written to the corresponding element in the struct.
+//
+// The following tags on struct fields have special meaning to Unmarshal:
+//
+//	application specifies that an APPLICATION tag is used
+//	private     specifies that a PRIVATE tag is used
+//	default:x   sets the default value for optional integer fields (only used if optional is also present)
+//	explicit    specifies that an additional, explicit tag wraps the implicit one
+//	optional    marks the field as ASN.1 OPTIONAL
+//	set         causes a SET, rather than a SEQUENCE type to be expected
+//	tag:x       specifies the ASN.1 tag number; implies ASN.1 CONTEXT SPECIFIC
+//
+// When decoding an ASN.1 value with an IMPLICIT tag into a string field,
+// Unmarshal will default to a PrintableString, which doesn't support
+// characters such as '@' and '&'. To force other encodings, use the following
+// tags:
+//
+//	ia5     causes strings to be unmarshaled as ASN.1 IA5String values
+//	numeric causes strings to be unmarshaled as ASN.1 NumericString values
+//	utf8    causes strings to be unmarshaled as ASN.1 UTF8String values
+//
+// If the type of the first field of a structure is RawContent then the raw
+// ASN1 contents of the struct will be stored in it.
+//
+// If the name of a slice type ends with "SET" then it's treated as if
+// the "set" tag was set on it. This results in interpreting the type as a
+// SET OF x rather than a SEQUENCE OF x. This can be used with nested slices
+// where a struct tag cannot be given.
+//
+// Other ASN.1 types are not supported; if it encounters them,
+// Unmarshal returns a parse error.
+func Unmarshal(b []byte, val any) (rest []byte, err error) {
+	return UnmarshalWithParams(b, val, "")
+}
+
+// An invalidUnmarshalError describes an invalid argument passed to Unmarshal.
+// (The argument to Unmarshal must be a non-nil pointer.)
+type invalidUnmarshalError struct {
+	Type reflect.Type
+}
+
+func (e *invalidUnmarshalError) Error() string {
+	if e.Type == nil {
+		return "asn1: Unmarshal recipient value is nil"
+	}
+
+	if e.Type.Kind() != reflect.Pointer {
+		return "asn1: Unmarshal recipient value is non-pointer " + e.Type.String()
+	}
+	return "asn1: Unmarshal recipient value is nil " + e.Type.String()
+}
+
+// UnmarshalWithParams allows field parameters to be specified for the
+// top-level element. The form of the params is the same as the field tags.
+func UnmarshalWithParams(b []byte, val any, params string) (rest []byte, err error) {
+	v := reflect.ValueOf(val)
+	if v.Kind() != reflect.Pointer || v.IsNil() {
+		return nil, &invalidUnmarshalError{reflect.TypeOf(val)}
+	}
+	offset, err := parseField(v.Elem(), b, 0, parseFieldParameters(params))
+	if err != nil {
+		return nil, err
+	}
+	return b[offset:], nil
+}
diff --git a/contrib/go/_std_1.18/src/encoding/asn1/common.go b/contrib/go/_std_1.19/src/encoding/asn1/common.go
index 40115df8b4..40115df8b4 100644
--- a/contrib/go/_std_1.18/src/encoding/asn1/common.go
+++ b/contrib/go/_std_1.19/src/encoding/asn1/common.go
diff --git a/contrib/go/_std_1.18/src/encoding/asn1/marshal.go b/contrib/go/_std_1.19/src/encoding/asn1/marshal.go
index c243349175..c243349175 100644
--- a/contrib/go/_std_1.18/src/encoding/asn1/marshal.go
+++ b/contrib/go/_std_1.19/src/encoding/asn1/marshal.go
diff --git a/contrib/go/_std_1.18/src/encoding/base64/base64.go b/contrib/go/_std_1.19/src/encoding/base64/base64.go
index 4a3e590649..4a3e590649 100644
--- a/contrib/go/_std_1.18/src/encoding/base64/base64.go
+++ b/contrib/go/_std_1.19/src/encoding/base64/base64.go
diff --git a/contrib/go/_std_1.19/src/encoding/binary/binary.go b/contrib/go/_std_1.19/src/encoding/binary/binary.go
new file mode 100644
index 0000000000..0681511fbb
--- /dev/null
+++ b/contrib/go/_std_1.19/src/encoding/binary/binary.go
@@ -0,0 +1,804 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package binary implements simple translation between numbers and byte
+// sequences and encoding and decoding of varints.
+//
+// Numbers are translated by reading and writing fixed-size values.
+// A fixed-size value is either a fixed-size arithmetic
+// type (bool, int8, uint8, int16, float32, complex64, ...)
+// or an array or struct containing only fixed-size values.
+//
+// The varint functions encode and decode single integer values using
+// a variable-length encoding; smaller values require fewer bytes.
+// For a specification, see
+// https://developers.google.com/protocol-buffers/docs/encoding.
+//
+// This package favors simplicity over efficiency. Clients that require
+// high-performance serialization, especially for large data structures,
+// should look at more advanced solutions such as the encoding/gob
+// package or protocol buffers.
+package binary
+
+import (
+	"errors"
+	"io"
+	"math"
+	"reflect"
+	"sync"
+)
+
+// A ByteOrder specifies how to convert byte slices into
+// 16-, 32-, or 64-bit unsigned integers.
+type ByteOrder interface {
+	Uint16([]byte) uint16
+	Uint32([]byte) uint32
+	Uint64([]byte) uint64
+	PutUint16([]byte, uint16)
+	PutUint32([]byte, uint32)
+	PutUint64([]byte, uint64)
+	String() string
+}
+
+// AppendByteOrder specifies how to append 16-, 32-, or 64-bit unsigned integers
+// into a byte slice.
+type AppendByteOrder interface {
+	AppendUint16([]byte, uint16) []byte
+	AppendUint32([]byte, uint32) []byte
+	AppendUint64([]byte, uint64) []byte
+	String() string
+}
+
+// LittleEndian is the little-endian implementation of ByteOrder and AppendByteOrder.
+var LittleEndian littleEndian
+
+// BigEndian is the big-endian implementation of ByteOrder and AppendByteOrder.
+var BigEndian bigEndian
+
+type littleEndian struct{}
+
+func (littleEndian) Uint16(b []byte) uint16 {
+	_ = b[1] // bounds check hint to compiler; see golang.org/issue/14808
+	return uint16(b[0]) | uint16(b[1])<<8
+}
+
+func (littleEndian) PutUint16(b []byte, v uint16) {
+	_ = b[1] // early bounds check to guarantee safety of writes below
+	b[0] = byte(v)
+	b[1] = byte(v >> 8)
+}
+
+func (littleEndian) AppendUint16(b []byte, v uint16) []byte {
+	return append(b,
+		byte(v),
+		byte(v>>8),
+	)
+}
+
+func (littleEndian) Uint32(b []byte) uint32 {
+	_ = b[3] // bounds check hint to compiler; see golang.org/issue/14808
+	return uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24
+}
+
+func (littleEndian) PutUint32(b []byte, v uint32) {
+	_ = b[3] // early bounds check to guarantee safety of writes below
+	b[0] = byte(v)
+	b[1] = byte(v >> 8)
+	b[2] = byte(v >> 16)
+	b[3] = byte(v >> 24)
+}
+
+func (littleEndian) AppendUint32(b []byte, v uint32) []byte {
+	return append(b,
+		byte(v),
+		byte(v>>8),
+		byte(v>>16),
+		byte(v>>24),
+	)
+}
+
+func (littleEndian) Uint64(b []byte) uint64 {
+	_ = b[7] // bounds check hint to compiler; see golang.org/issue/14808
+	return uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 |
+		uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56
+}
+
+func (littleEndian) PutUint64(b []byte, v uint64) {
+	_ = b[7] // early bounds check to guarantee safety of writes below
+	b[0] = byte(v)
+	b[1] = byte(v >> 8)
+	b[2] = byte(v >> 16)
+	b[3] = byte(v >> 24)
+	b[4] = byte(v >> 32)
+	b[5] = byte(v >> 40)
+	b[6] = byte(v >> 48)
+	b[7] = byte(v >> 56)
+}
+
+func (littleEndian) AppendUint64(b []byte, v uint64) []byte {
+	return append(b,
+		byte(v),
+		byte(v>>8),
+		byte(v>>16),
+		byte(v>>24),
+		byte(v>>32),
+		byte(v>>40),
+		byte(v>>48),
+		byte(v>>56),
+	)
+}
+
+func (littleEndian) String() string { return "LittleEndian" }
+
+func (littleEndian) GoString() string { return "binary.LittleEndian" }
+
+type bigEndian struct{}
+
+func (bigEndian) Uint16(b []byte) uint16 {
+	_ = b[1] // bounds check hint to compiler; see golang.org/issue/14808
+	return uint16(b[1]) | uint16(b[0])<<8
+}
+
+func (bigEndian) PutUint16(b []byte, v uint16) {
+	_ = b[1] // early bounds check to guarantee safety of writes below
+	b[0] = byte(v >> 8)
+	b[1] = byte(v)
+}
+
+func (bigEndian) AppendUint16(b []byte, v uint16) []byte {
+	return append(b,
+		byte(v>>8),
+		byte(v),
+	)
+}
+
+func (bigEndian) Uint32(b []byte) uint32 {
+	_ = b[3] // bounds check hint to compiler; see golang.org/issue/14808
+	return uint32(b[3]) | uint32(b[2])<<8 | uint32(b[1])<<16 | uint32(b[0])<<24
+}
+
+func (bigEndian) PutUint32(b []byte, v uint32) {
+	_ = b[3] // early bounds check to guarantee safety of writes below
+	b[0] = byte(v >> 24)
+	b[1] = byte(v >> 16)
+	b[2] = byte(v >> 8)
+	b[3] = byte(v)
+}
+
+func (bigEndian) AppendUint32(b []byte, v uint32) []byte {
+	return append(b,
+		byte(v>>24),
+		byte(v>>16),
+		byte(v>>8),
+		byte(v),
+	)
+}
+
+func (bigEndian) Uint64(b []byte) uint64 {
+	_ = b[7] // bounds check hint to compiler; see golang.org/issue/14808
+	return uint64(b[7]) | uint64(b[6])<<8 | uint64(b[5])<<16 | uint64(b[4])<<24 |
+		uint64(b[3])<<32 | uint64(b[2])<<40 | uint64(b[1])<<48 | uint64(b[0])<<56
+}
+
+func (bigEndian) PutUint64(b []byte, v uint64) {
+	_ = b[7] // early bounds check to guarantee safety of writes below
+	b[0] = byte(v >> 56)
+	b[1] = byte(v >> 48)
+	b[2] = byte(v >> 40)
+	b[3] = byte(v >> 32)
+	b[4] = byte(v >> 24)
+	b[5] = byte(v >> 16)
+	b[6] = byte(v >> 8)
+	b[7] = byte(v)
+}
+
+func (bigEndian) AppendUint64(b []byte, v uint64) []byte {
+	return append(b,
+		byte(v>>56),
+		byte(v>>48),
+		byte(v>>40),
+		byte(v>>32),
+		byte(v>>24),
+		byte(v>>16),
+		byte(v>>8),
+		byte(v),
+	)
+}
+
+func (bigEndian) String() string { return "BigEndian" }
+
+func (bigEndian) GoString() string { return "binary.BigEndian" }
+
+// Read reads structured binary data from r into data.
+// Data must be a pointer to a fixed-size value or a slice
+// of fixed-size values.
+// Bytes read from r are decoded using the specified byte order
+// and written to successive fields of the data.
+// When decoding boolean values, a zero byte is decoded as false, and
+// any other non-zero byte is decoded as true.
+// When reading into structs, the field data for fields with
+// blank (_) field names is skipped; i.e., blank field names
+// may be used for padding.
+// When reading into a struct, all non-blank fields must be exported
+// or Read may panic.
+//
+// The error is EOF only if no bytes were read.
+// If an EOF happens after reading some but not all the bytes,
+// Read returns ErrUnexpectedEOF.
+func Read(r io.Reader, order ByteOrder, data any) error {
+	// Fast path for basic types and slices.
+	if n := intDataSize(data); n != 0 {
+		bs := make([]byte, n)
+		if _, err := io.ReadFull(r, bs); err != nil {
+			return err
+		}
+		switch data := data.(type) {
+		case *bool:
+			*data = bs[0] != 0
+		case *int8:
+			*data = int8(bs[0])
+		case *uint8:
+			*data = bs[0]
+		case *int16:
+			*data = int16(order.Uint16(bs))
+		case *uint16:
+			*data = order.Uint16(bs)
+		case *int32:
+			*data = int32(order.Uint32(bs))
+		case *uint32:
+			*data = order.Uint32(bs)
+		case *int64:
+			*data = int64(order.Uint64(bs))
+		case *uint64:
+			*data = order.Uint64(bs)
+		case *float32:
+			*data = math.Float32frombits(order.Uint32(bs))
+		case *float64:
+			*data = math.Float64frombits(order.Uint64(bs))
+		case []bool:
+			for i, x := range bs { // Easier to loop over the input for 8-bit values.
+				data[i] = x != 0
+			}
+		case []int8:
+			for i, x := range bs {
+				data[i] = int8(x)
+			}
+		case []uint8:
+			copy(data, bs)
+		case []int16:
+			for i := range data {
+				data[i] = int16(order.Uint16(bs[2*i:]))
+			}
+		case []uint16:
+			for i := range data {
+				data[i] = order.Uint16(bs[2*i:])
+			}
+		case []int32:
+			for i := range data {
+				data[i] = int32(order.Uint32(bs[4*i:]))
+			}
+		case []uint32:
+			for i := range data {
+				data[i] = order.Uint32(bs[4*i:])
+			}
+		case []int64:
+			for i := range data {
+				data[i] = int64(order.Uint64(bs[8*i:]))
+			}
+		case []uint64:
+			for i := range data {
+				data[i] = order.Uint64(bs[8*i:])
+			}
+		case []float32:
+			for i := range data {
+				data[i] = math.Float32frombits(order.Uint32(bs[4*i:]))
+			}
+		case []float64:
+			for i := range data {
+				data[i] = math.Float64frombits(order.Uint64(bs[8*i:]))
+			}
+		default:
+			n = 0 // fast path doesn't apply
+		}
+		if n != 0 {
+			return nil
+		}
+	}
+
+	// Fallback to reflect-based decoding.
+	v := reflect.ValueOf(data)
+	size := -1
+	switch v.Kind() {
+	case reflect.Pointer:
+		v = v.Elem()
+		size = dataSize(v)
+	case reflect.Slice:
+		size = dataSize(v)
+	}
+	if size < 0 {
+		return errors.New("binary.Read: invalid type " + reflect.TypeOf(data).String())
+	}
+	d := &decoder{order: order, buf: make([]byte, size)}
+	if _, err := io.ReadFull(r, d.buf); err != nil {
+		return err
+	}
+	d.value(v)
+	return nil
+}
+
+// Write writes the binary representation of data into w.
+// Data must be a fixed-size value or a slice of fixed-size
+// values, or a pointer to such data.
+// Boolean values encode as one byte: 1 for true, and 0 for false.
+// Bytes written to w are encoded using the specified byte order
+// and read from successive fields of the data.
+// When writing structs, zero values are written for fields
+// with blank (_) field names.
+func Write(w io.Writer, order ByteOrder, data any) error {
+	// Fast path for basic types and slices.
+	if n := intDataSize(data); n != 0 {
+		bs := make([]byte, n)
+		switch v := data.(type) {
+		case *bool:
+			if *v {
+				bs[0] = 1
+			} else {
+				bs[0] = 0
+			}
+		case bool:
+			if v {
+				bs[0] = 1
+			} else {
+				bs[0] = 0
+			}
+		case []bool:
+			for i, x := range v {
+				if x {
+					bs[i] = 1
+				} else {
+					bs[i] = 0
+				}
+			}
+		case *int8:
+			bs[0] = byte(*v)
+		case int8:
+			bs[0] = byte(v)
+		case []int8:
+			for i, x := range v {
+				bs[i] = byte(x)
+			}
+		case *uint8:
+			bs[0] = *v
+		case uint8:
+			bs[0] = v
+		case []uint8:
+			bs = v
+		case *int16:
+			order.PutUint16(bs, uint16(*v))
+		case int16:
+			order.PutUint16(bs, uint16(v))
+		case []int16:
+			for i, x := range v {
+				order.PutUint16(bs[2*i:], uint16(x))
+			}
+		case *uint16:
+			order.PutUint16(bs, *v)
+		case uint16:
+			order.PutUint16(bs, v)
+		case []uint16:
+			for i, x := range v {
+				order.PutUint16(bs[2*i:], x)
+			}
+		case *int32:
+			order.PutUint32(bs, uint32(*v))
+		case int32:
+			order.PutUint32(bs, uint32(v))
+		case []int32:
+			for i, x := range v {
+				order.PutUint32(bs[4*i:], uint32(x))
+			}
+		case *uint32:
+			order.PutUint32(bs, *v)
+		case uint32:
+			order.PutUint32(bs, v)
+		case []uint32:
+			for i, x := range v {
+				order.PutUint32(bs[4*i:], x)
+			}
+		case *int64:
+			order.PutUint64(bs, uint64(*v))
+		case int64:
+			order.PutUint64(bs, uint64(v))
+		case []int64:
+			for i, x := range v {
+				order.PutUint64(bs[8*i:], uint64(x))
+			}
+		case *uint64:
+			order.PutUint64(bs, *v)
+		case uint64:
+			order.PutUint64(bs, v)
+		case []uint64:
+			for i, x := range v {
+				order.PutUint64(bs[8*i:], x)
+			}
+		case *float32:
+			order.PutUint32(bs, math.Float32bits(*v))
+		case float32:
+			order.PutUint32(bs, math.Float32bits(v))
+		case []float32:
+			for i, x := range v {
+				order.PutUint32(bs[4*i:], math.Float32bits(x))
+			}
+		case *float64:
+			order.PutUint64(bs, math.Float64bits(*v))
+		case float64:
+			order.PutUint64(bs, math.Float64bits(v))
+		case []float64:
+			for i, x := range v {
+				order.PutUint64(bs[8*i:], math.Float64bits(x))
+			}
+		}
+		_, err := w.Write(bs)
+		return err
+	}
+
+	// Fallback to reflect-based encoding.
+	v := reflect.Indirect(reflect.ValueOf(data))
+	size := dataSize(v)
+	if size < 0 {
+		return errors.New("binary.Write: invalid type " + reflect.TypeOf(data).String())
+	}
+	buf := make([]byte, size)
+	e := &encoder{order: order, buf: buf}
+	e.value(v)
+	_, err := w.Write(buf)
+	return err
+}
+
+// Size returns how many bytes Write would generate to encode the value v, which
+// must be a fixed-size value or a slice of fixed-size values, or a pointer to such data.
+// If v is neither of these, Size returns -1.
+func Size(v any) int {
+	return dataSize(reflect.Indirect(reflect.ValueOf(v)))
+}
+
+var structSize sync.Map // map[reflect.Type]int
+
+// dataSize returns the number of bytes the actual data represented by v occupies in memory.
+// For compound structures, it sums the sizes of the elements. Thus, for instance, for a slice
+// it returns the length of the slice times the element size and does not count the memory
+// occupied by the header. If the type of v is not acceptable, dataSize returns -1.
+func dataSize(v reflect.Value) int {
+	switch v.Kind() {
+	case reflect.Slice:
+		if s := sizeof(v.Type().Elem()); s >= 0 {
+			return s * v.Len()
+		}
+		return -1
+
+	case reflect.Struct:
+		t := v.Type()
+		if size, ok := structSize.Load(t); ok {
+			return size.(int)
+		}
+		size := sizeof(t)
+		structSize.Store(t, size)
+		return size
+
+	default:
+		return sizeof(v.Type())
+	}
+}
+
+// sizeof returns the size >= 0 of variables for the given type or -1 if the type is not acceptable.
+func sizeof(t reflect.Type) int {
+	switch t.Kind() {
+	case reflect.Array:
+		if s := sizeof(t.Elem()); s >= 0 {
+			return s * t.Len()
+		}
+
+	case reflect.Struct:
+		sum := 0
+		for i, n := 0, t.NumField(); i < n; i++ {
+			s := sizeof(t.Field(i).Type)
+			if s < 0 {
+				return -1
+			}
+			sum += s
+		}
+		return sum
+
+	case reflect.Bool,
+		reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64,
+		reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64,
+		reflect.Float32, reflect.Float64, reflect.Complex64, reflect.Complex128:
+		return int(t.Size())
+	}
+
+	return -1
+}
+
+type coder struct {
+	order  ByteOrder
+	buf    []byte
+	offset int
+}
+
+type decoder coder
+type encoder coder
+
+func (d *decoder) bool() bool {
+	x := d.buf[d.offset]
+	d.offset++
+	return x != 0
+}
+
+func (e *encoder) bool(x bool) {
+	if x {
+		e.buf[e.offset] = 1
+	} else {
+		e.buf[e.offset] = 0
+	}
+	e.offset++
+}
+
+func (d *decoder) uint8() uint8 {
+	x := d.buf[d.offset]
+	d.offset++
+	return x
+}
+
+func (e *encoder) uint8(x uint8) {
+	e.buf[e.offset] = x
+	e.offset++
+}
+
+func (d *decoder) uint16() uint16 {
+	x := d.order.Uint16(d.buf[d.offset : d.offset+2])
+	d.offset += 2
+	return x
+}
+
+func (e *encoder) uint16(x uint16) {
+	e.order.PutUint16(e.buf[e.offset:e.offset+2], x)
+	e.offset += 2
+}
+
+func (d *decoder) uint32() uint32 {
+	x := d.order.Uint32(d.buf[d.offset : d.offset+4])
+	d.offset += 4
+	return x
+}
+
+func (e *encoder) uint32(x uint32) {
+	e.order.PutUint32(e.buf[e.offset:e.offset+4], x)
+	e.offset += 4
+}
+
+func (d *decoder) uint64() uint64 {
+	x := d.order.Uint64(d.buf[d.offset : d.offset+8])
+	d.offset += 8
+	return x
+}
+
+func (e *encoder) uint64(x uint64) {
+	e.order.PutUint64(e.buf[e.offset:e.offset+8], x)
+	e.offset += 8
+}
+
+func (d *decoder) int8() int8 { return int8(d.uint8()) }
+
+func (e *encoder) int8(x int8) { e.uint8(uint8(x)) }
+
+func (d *decoder) int16() int16 { return int16(d.uint16()) }
+
+func (e *encoder) int16(x int16) { e.uint16(uint16(x)) }
+
+func (d *decoder) int32() int32 { return int32(d.uint32()) }
+
+func (e *encoder) int32(x int32) { e.uint32(uint32(x)) }
+
+func (d *decoder) int64() int64 { return int64(d.uint64()) }
+
+func (e *encoder) int64(x int64) { e.uint64(uint64(x)) }
+
+func (d *decoder) value(v reflect.Value) {
+	switch v.Kind() {
+	case reflect.Array:
+		l := v.Len()
+		for i := 0; i < l; i++ {
+			d.value(v.Index(i))
+		}
+
+	case reflect.Struct:
+		t := v.Type()
+		l := v.NumField()
+		for i := 0; i < l; i++ {
+			// Note: Calling v.CanSet() below is an optimization.
+			// It would be sufficient to check the field name,
+			// but creating the StructField info for each field is
+			// costly (run "go test -bench=ReadStruct" and compare
+			// results when making changes to this code).
+			if v := v.Field(i); v.CanSet() || t.Field(i).Name != "_" {
+				d.value(v)
+			} else {
+				d.skip(v)
+			}
+		}
+
+	case reflect.Slice:
+		l := v.Len()
+		for i := 0; i < l; i++ {
+			d.value(v.Index(i))
+		}
+
+	case reflect.Bool:
+		v.SetBool(d.bool())
+
+	case reflect.Int8:
+		v.SetInt(int64(d.int8()))
+	case reflect.Int16:
+		v.SetInt(int64(d.int16()))
+	case reflect.Int32:
+		v.SetInt(int64(d.int32()))
+	case reflect.Int64:
+		v.SetInt(d.int64())
+
+	case reflect.Uint8:
+		v.SetUint(uint64(d.uint8()))
+	case reflect.Uint16:
+		v.SetUint(uint64(d.uint16()))
+	case reflect.Uint32:
+		v.SetUint(uint64(d.uint32()))
+	case reflect.Uint64:
+		v.SetUint(d.uint64())
+
+	case reflect.Float32:
+		v.SetFloat(float64(math.Float32frombits(d.uint32())))
+	case reflect.Float64:
+		v.SetFloat(math.Float64frombits(d.uint64()))
+
+	case reflect.Complex64:
+		v.SetComplex(complex(
+			float64(math.Float32frombits(d.uint32())),
+			float64(math.Float32frombits(d.uint32())),
+		))
+	case reflect.Complex128:
+		v.SetComplex(complex(
+			math.Float64frombits(d.uint64()),
+			math.Float64frombits(d.uint64()),
+		))
+	}
+}
+
+func (e *encoder) value(v reflect.Value) {
+	switch v.Kind() {
+	case reflect.Array:
+		l := v.Len()
+		for i := 0; i < l; i++ {
+			e.value(v.Index(i))
+		}
+
+	case reflect.Struct:
+		t := v.Type()
+		l := v.NumField()
+		for i := 0; i < l; i++ {
+			// see comment for corresponding code in decoder.value()
+			if v := v.Field(i); v.CanSet() || t.Field(i).Name != "_" {
+				e.value(v)
+			} else {
+				e.skip(v)
+			}
+		}
+
+	case reflect.Slice:
+		l := v.Len()
+		for i := 0; i < l; i++ {
+			e.value(v.Index(i))
+		}
+
+	case reflect.Bool:
+		e.bool(v.Bool())
+
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		switch v.Type().Kind() {
+		case reflect.Int8:
+			e.int8(int8(v.Int()))
+		case reflect.Int16:
+			e.int16(int16(v.Int()))
+		case reflect.Int32:
+			e.int32(int32(v.Int()))
+		case reflect.Int64:
+			e.int64(v.Int())
+		}
+
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		switch v.Type().Kind() {
+		case reflect.Uint8:
+			e.uint8(uint8(v.Uint()))
+		case reflect.Uint16:
+			e.uint16(uint16(v.Uint()))
+		case reflect.Uint32:
+			e.uint32(uint32(v.Uint()))
+		case reflect.Uint64:
+			e.uint64(v.Uint())
+		}
+
+	case reflect.Float32, reflect.Float64:
+		switch v.Type().Kind() {
+		case reflect.Float32:
+			e.uint32(math.Float32bits(float32(v.Float())))
+		case reflect.Float64:
+			e.uint64(math.Float64bits(v.Float()))
+		}
+
+	case reflect.Complex64, reflect.Complex128:
+		switch v.Type().Kind() {
+		case reflect.Complex64:
+			x := v.Complex()
+			e.uint32(math.Float32bits(float32(real(x))))
+			e.uint32(math.Float32bits(float32(imag(x))))
+		case reflect.Complex128:
+			x := v.Complex()
+			e.uint64(math.Float64bits(real(x)))
+			e.uint64(math.Float64bits(imag(x)))
+		}
+	}
+}
+
+func (d *decoder) skip(v reflect.Value) {
+	d.offset += dataSize(v)
+}
+
+func (e *encoder) skip(v reflect.Value) {
+	n := dataSize(v)
+	zero := e.buf[e.offset : e.offset+n]
+	for i := range zero {
+		zero[i] = 0
+	}
+	e.offset += n
+}
+
+// intDataSize returns the size of the data required to represent the data when encoded.
+// It returns zero if the type cannot be implemented by the fast path in Read or Write.
+func intDataSize(data any) int {
+	switch data := data.(type) {
+	case bool, int8, uint8, *bool, *int8, *uint8:
+		return 1
+	case []bool:
+		return len(data)
+	case []int8:
+		return len(data)
+	case []uint8:
+		return len(data)
+	case int16, uint16, *int16, *uint16:
+		return 2
+	case []int16:
+		return 2 * len(data)
+	case []uint16:
+		return 2 * len(data)
+	case int32, uint32, *int32, *uint32:
+		return 4
+	case []int32:
+		return 4 * len(data)
+	case []uint32:
+		return 4 * len(data)
+	case int64, uint64, *int64, *uint64:
+		return 8
+	case []int64:
+		return 8 * len(data)
+	case []uint64:
+		return 8 * len(data)
+	case float32, *float32:
+		return 4
+	case float64, *float64:
+		return 8
+	case []float32:
+		return 4 * len(data)
+	case []float64:
+		return 8 * len(data)
+	}
+	return 0
+}
diff --git a/contrib/go/_std_1.19/src/encoding/binary/varint.go b/contrib/go/_std_1.19/src/encoding/binary/varint.go
new file mode 100644
index 0000000000..c807d15f44
--- /dev/null
+++ b/contrib/go/_std_1.19/src/encoding/binary/varint.go
@@ -0,0 +1,157 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package binary
+
+// This file implements "varint" encoding of 64-bit integers.
+// The encoding is:
+// - unsigned integers are serialized 7 bits at a time, starting with the
+//   least significant bits
+// - the most significant bit (msb) in each output byte indicates if there
+//   is a continuation byte (msb = 1)
+// - signed integers are mapped to unsigned integers using "zig-zag"
+//   encoding: Positive values x are written as 2*x + 0, negative values
+//   are written as 2*(^x) + 1; that is, negative numbers are complemented
+//   and whether to complement is encoded in bit 0.
+//
+// Design note:
+// At most 10 bytes are needed for 64-bit values. The encoding could
+// be more dense: a full 64-bit value needs an extra byte just to hold bit 63.
+// Instead, the msb of the previous byte could be used to hold bit 63 since we
+// know there can't be more than 64 bits. This is a trivial improvement and
+// would reduce the maximum encoding length to 9 bytes. However, it breaks the
+// invariant that the msb is always the "continuation bit" and thus makes the
+// format incompatible with a varint encoding for larger numbers (say 128-bit).
+
+import (
+	"errors"
+	"io"
+)
+
+// MaxVarintLenN is the maximum length of a varint-encoded N-bit integer.
+const (
+	MaxVarintLen16 = 3
+	MaxVarintLen32 = 5
+	MaxVarintLen64 = 10
+)
+
+// AppendUvarint appends the varint-encoded form of x,
+// as generated by PutUvarint, to buf and returns the extended buffer.
+func AppendUvarint(buf []byte, x uint64) []byte {
+	for x >= 0x80 {
+		buf = append(buf, byte(x)|0x80)
+		x >>= 7
+	}
+	return append(buf, byte(x))
+}
+
+// PutUvarint encodes a uint64 into buf and returns the number of bytes written.
+// If the buffer is too small, PutUvarint will panic.
+func PutUvarint(buf []byte, x uint64) int {
+	i := 0
+	for x >= 0x80 {
+		buf[i] = byte(x) | 0x80
+		x >>= 7
+		i++
+	}
+	buf[i] = byte(x)
+	return i + 1
+}
+
+// Uvarint decodes a uint64 from buf and returns that value and the
+// number of bytes read (> 0). If an error occurred, the value is 0
+// and the number of bytes n is <= 0 meaning:
+//
+//	n == 0: buf too small
+//	n  < 0: value larger than 64 bits (overflow)
+//	        and -n is the number of bytes read
+func Uvarint(buf []byte) (uint64, int) {
+	var x uint64
+	var s uint
+	for i, b := range buf {
+		if i == MaxVarintLen64 {
+			// Catch byte reads past MaxVarintLen64.
+			// See issue https://golang.org/issues/41185
+			return 0, -(i + 1) // overflow
+		}
+		if b < 0x80 {
+			if i == MaxVarintLen64-1 && b > 1 {
+				return 0, -(i + 1) // overflow
+			}
+			return x | uint64(b)<<s, i + 1
+		}
+		x |= uint64(b&0x7f) << s
+		s += 7
+	}
+	return 0, 0
+}
+
+// AppendVarint appends the varint-encoded form of x,
+// as generated by PutVarint, to buf and returns the extended buffer.
+func AppendVarint(buf []byte, x int64) []byte {
+	ux := uint64(x) << 1
+	if x < 0 {
+		ux = ^ux
+	}
+	return AppendUvarint(buf, ux)
+}
+
+// PutVarint encodes an int64 into buf and returns the number of bytes written.
+// If the buffer is too small, PutVarint will panic.
+func PutVarint(buf []byte, x int64) int {
+	ux := uint64(x) << 1
+	if x < 0 {
+		ux = ^ux
+	}
+	return PutUvarint(buf, ux)
+}
+
+// Varint decodes an int64 from buf and returns that value and the
+// number of bytes read (> 0). If an error occurred, the value is 0
+// and the number of bytes n is <= 0 with the following meaning:
+//
+//	n == 0: buf too small
+//	n  < 0: value larger than 64 bits (overflow)
+//	        and -n is the number of bytes read
+func Varint(buf []byte) (int64, int) {
+	ux, n := Uvarint(buf) // ok to continue in presence of error
+	x := int64(ux >> 1)
+	if ux&1 != 0 {
+		x = ^x
+	}
+	return x, n
+}
+
+var overflow = errors.New("binary: varint overflows a 64-bit integer")
+
+// ReadUvarint reads an encoded unsigned integer from r and returns it as a uint64.
+func ReadUvarint(r io.ByteReader) (uint64, error) {
+	var x uint64
+	var s uint
+	for i := 0; i < MaxVarintLen64; i++ {
+		b, err := r.ReadByte()
+		if err != nil {
+			return x, err
+		}
+		if b < 0x80 {
+			if i == MaxVarintLen64-1 && b > 1 {
+				return x, overflow
+			}
+			return x | uint64(b)<<s, nil
+		}
+		x |= uint64(b&0x7f) << s
+		s += 7
+	}
+	return x, overflow
+}
+
+// ReadVarint reads an encoded signed integer from r and returns it as an int64.
+func ReadVarint(r io.ByteReader) (int64, error) {
+	ux, err := ReadUvarint(r) // ok to continue in presence of error
+	x := int64(ux >> 1)
+	if ux&1 != 0 {
+		x = ^x
+	}
+	return x, err
+}
diff --git a/contrib/go/_std_1.19/src/encoding/csv/reader.go b/contrib/go/_std_1.19/src/encoding/csv/reader.go
new file mode 100644
index 0000000000..90a37e6074
--- /dev/null
+++ b/contrib/go/_std_1.19/src/encoding/csv/reader.go
@@ -0,0 +1,462 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package csv reads and writes comma-separated values (CSV) files.
+// There are many kinds of CSV files; this package supports the format
+// described in RFC 4180.
+//
+// A csv file contains zero or more records of one or more fields per record.
+// Each record is separated by the newline character. The final record may
+// optionally be followed by a newline character.
+//
+//	field1,field2,field3
+//
+// White space is considered part of a field.
+//
+// Carriage returns before newline characters are silently removed.
+//
+// Blank lines are ignored. A line with only whitespace characters (excluding
+// the ending newline character) is not considered a blank line.
+//
+// Fields which start and stop with the quote character " are called
+// quoted-fields. The beginning and ending quote are not part of the
+// field.
+//
+// The source:
+//
+//	normal string,"quoted-field"
+//
+// results in the fields
+//
+//	{`normal string`, `quoted-field`}
+//
+// Within a quoted-field a quote character followed by a second quote
+// character is considered a single quote.
+//
+//	"the ""word"" is true","a ""quoted-field"""
+//
+// results in
+//
+//	{`the "word" is true`, `a "quoted-field"`}
+//
+// Newlines and commas may be included in a quoted-field
+//
+//	"Multi-line
+//	field","comma is ,"
+//
+// results in
+//
+//	{`Multi-line
+//	field`, `comma is ,`}
+package csv
+
+import (
+	"bufio"
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+	"unicode"
+	"unicode/utf8"
+)
+
+// A ParseError is returned for parsing errors.
+// Line numbers are 1-indexed and columns are 0-indexed.
+type ParseError struct {
+	StartLine int   // Line where the record starts
+	Line      int   // Line where the error occurred
+	Column    int   // Column (1-based byte index) where the error occurred
+	Err       error // The actual error
+}
+
+func (e *ParseError) Error() string {
+	if e.Err == ErrFieldCount {
+		return fmt.Sprintf("record on line %d: %v", e.Line, e.Err)
+	}
+	if e.StartLine != e.Line {
+		return fmt.Sprintf("record on line %d; parse error on line %d, column %d: %v", e.StartLine, e.Line, e.Column, e.Err)
+	}
+	return fmt.Sprintf("parse error on line %d, column %d: %v", e.Line, e.Column, e.Err)
+}
+
+func (e *ParseError) Unwrap() error { return e.Err }
+
+// These are the errors that can be returned in ParseError.Err.
+var (
+	ErrTrailingComma = errors.New("extra delimiter at end of line") // Deprecated: No longer used.
+	ErrBareQuote     = errors.New("bare \" in non-quoted-field")
+	ErrQuote         = errors.New("extraneous or missing \" in quoted-field")
+	ErrFieldCount    = errors.New("wrong number of fields")
+)
+
+var errInvalidDelim = errors.New("csv: invalid field or comment delimiter")
+
+func validDelim(r rune) bool {
+	return r != 0 && r != '"' && r != '\r' && r != '\n' && utf8.ValidRune(r) && r != utf8.RuneError
+}
+
+// A Reader reads records from a CSV-encoded file.
+//
+// As returned by NewReader, a Reader expects input conforming to RFC 4180.
+// The exported fields can be changed to customize the details before the
+// first call to Read or ReadAll.
+//
+// The Reader converts all \r\n sequences in its input to plain \n,
+// including in multiline field values, so that the returned data does
+// not depend on which line-ending convention an input file uses.
+type Reader struct {
+	// Comma is the field delimiter.
+	// It is set to comma (',') by NewReader.
+	// Comma must be a valid rune and must not be \r, \n,
+	// or the Unicode replacement character (0xFFFD).
+	Comma rune
+
+	// Comment, if not 0, is the comment character. Lines beginning with the
+	// Comment character without preceding whitespace are ignored.
+	// With leading whitespace the Comment character becomes part of the
+	// field, even if TrimLeadingSpace is true.
+	// Comment must be a valid rune and must not be \r, \n,
+	// or the Unicode replacement character (0xFFFD).
+	// It must also not be equal to Comma.
+	Comment rune
+
+	// FieldsPerRecord is the number of expected fields per record.
+	// If FieldsPerRecord is positive, Read requires each record to
+	// have the given number of fields. If FieldsPerRecord is 0, Read sets it to
+	// the number of fields in the first record, so that future records must
+	// have the same field count. If FieldsPerRecord is negative, no check is
+	// made and records may have a variable number of fields.
+	FieldsPerRecord int
+
+	// If LazyQuotes is true, a quote may appear in an unquoted field and a
+	// non-doubled quote may appear in a quoted field.
+	LazyQuotes bool
+
+	// If TrimLeadingSpace is true, leading white space in a field is ignored.
+	// This is done even if the field delimiter, Comma, is white space.
+	TrimLeadingSpace bool
+
+	// ReuseRecord controls whether calls to Read may return a slice sharing
+	// the backing array of the previous call's returned slice for performance.
+	// By default, each call to Read returns newly allocated memory owned by the caller.
+	ReuseRecord bool
+
+	TrailingComma bool // Deprecated: No longer used.
+
+	r *bufio.Reader
+
+	// numLine is the current line being read in the CSV file.
+	numLine int
+
+	// offset is the input stream byte offset of the current reader position.
+	offset int64
+
+	// rawBuffer is a line buffer only used by the readLine method.
+	rawBuffer []byte
+
+	// recordBuffer holds the unescaped fields, one after another.
+	// The fields can be accessed by using the indexes in fieldIndexes.
+	// E.g., For the row `a,"b","c""d",e`, recordBuffer will contain `abc"de`
+	// and fieldIndexes will contain the indexes [1, 2, 5, 6].
+	recordBuffer []byte
+
+	// fieldIndexes is an index of fields inside recordBuffer.
+	// The i'th field ends at offset fieldIndexes[i] in recordBuffer.
+	fieldIndexes []int
+
+	// fieldPositions is an index of field positions for the
+	// last record returned by Read.
+	fieldPositions []position
+
+	// lastRecord is a record cache and only used when ReuseRecord == true.
+	lastRecord []string
+}
+
+// NewReader returns a new Reader that reads from r.
+func NewReader(r io.Reader) *Reader {
+	return &Reader{
+		Comma: ',',
+		r:     bufio.NewReader(r),
+	}
+}
+
+// Read reads one record (a slice of fields) from r.
+// If the record has an unexpected number of fields,
+// Read returns the record along with the error ErrFieldCount.
+// Except for that case, Read always returns either a non-nil
+// record or a non-nil error, but not both.
+// If there is no data left to be read, Read returns nil, io.EOF.
+// If ReuseRecord is true, the returned slice may be shared
+// between multiple calls to Read.
+func (r *Reader) Read() (record []string, err error) {
+	if r.ReuseRecord {
+		record, err = r.readRecord(r.lastRecord)
+		r.lastRecord = record
+	} else {
+		record, err = r.readRecord(nil)
+	}
+	return record, err
+}
+
+// FieldPos returns the line and column corresponding to
+// the start of the field with the given index in the slice most recently
+// returned by Read. Numbering of lines and columns starts at 1;
+// columns are counted in bytes, not runes.
+//
+// If this is called with an out-of-bounds index, it panics.
+func (r *Reader) FieldPos(field int) (line, column int) {
+	if field < 0 || field >= len(r.fieldPositions) {
+		panic("out of range index passed to FieldPos")
+	}
+	p := &r.fieldPositions[field]
+	return p.line, p.col
+}
+
+// InputOffset returns the input stream byte offset of the current reader
+// position. The offset gives the location of the end of the most recently
+// read row and the beginning of the next row.
+func (r *Reader) InputOffset() int64 {
+	return r.offset
+}
+
+// pos holds the position of a field in the current line.
+type position struct {
+	line, col int
+}
+
+// ReadAll reads all the remaining records from r.
+// Each record is a slice of fields.
+// A successful call returns err == nil, not err == io.EOF. Because ReadAll is
+// defined to read until EOF, it does not treat end of file as an error to be
+// reported.
+func (r *Reader) ReadAll() (records [][]string, err error) {
+	for {
+		record, err := r.readRecord(nil)
+		if err == io.EOF {
+			return records, nil
+		}
+		if err != nil {
+			return nil, err
+		}
+		records = append(records, record)
+	}
+}
+
+// readLine reads the next line (with the trailing endline).
+// If EOF is hit without a trailing endline, it will be omitted.
+// If some bytes were read, then the error is never io.EOF.
+// The result is only valid until the next call to readLine.
+func (r *Reader) readLine() ([]byte, error) {
+	line, err := r.r.ReadSlice('\n')
+	if err == bufio.ErrBufferFull {
+		r.rawBuffer = append(r.rawBuffer[:0], line...)
+		for err == bufio.ErrBufferFull {
+			line, err = r.r.ReadSlice('\n')
+			r.rawBuffer = append(r.rawBuffer, line...)
+		}
+		line = r.rawBuffer
+	}
+	readSize := len(line)
+	if readSize > 0 && err == io.EOF {
+		err = nil
+		// For backwards compatibility, drop trailing \r before EOF.
+		if line[readSize-1] == '\r' {
+			line = line[:readSize-1]
+		}
+	}
+	r.numLine++
+	r.offset += int64(readSize)
+	// Normalize \r\n to \n on all input lines.
+	if n := len(line); n >= 2 && line[n-2] == '\r' && line[n-1] == '\n' {
+		line[n-2] = '\n'
+		line = line[:n-1]
+	}
+	return line, err
+}
+
+// lengthNL reports the number of bytes for the trailing \n.
+func lengthNL(b []byte) int {
+	if len(b) > 0 && b[len(b)-1] == '\n' {
+		return 1
+	}
+	return 0
+}
+
+// nextRune returns the next rune in b or utf8.RuneError.
+func nextRune(b []byte) rune {
+	r, _ := utf8.DecodeRune(b)
+	return r
+}
+
+func (r *Reader) readRecord(dst []string) ([]string, error) {
+	if r.Comma == r.Comment || !validDelim(r.Comma) || (r.Comment != 0 && !validDelim(r.Comment)) {
+		return nil, errInvalidDelim
+	}
+
+	// Read line (automatically skipping past empty lines and any comments).
+	var line []byte
+	var errRead error
+	for errRead == nil {
+		line, errRead = r.readLine()
+		if r.Comment != 0 && nextRune(line) == r.Comment {
+			line = nil
+			continue // Skip comment lines
+		}
+		if errRead == nil && len(line) == lengthNL(line) {
+			line = nil
+			continue // Skip empty lines
+		}
+		break
+	}
+	if errRead == io.EOF {
+		return nil, errRead
+	}
+
+	// Parse each field in the record.
+	var err error
+	const quoteLen = len(`"`)
+	commaLen := utf8.RuneLen(r.Comma)
+	recLine := r.numLine // Starting line for record
+	r.recordBuffer = r.recordBuffer[:0]
+	r.fieldIndexes = r.fieldIndexes[:0]
+	r.fieldPositions = r.fieldPositions[:0]
+	pos := position{line: r.numLine, col: 1}
+parseField:
+	for {
+		if r.TrimLeadingSpace {
+			i := bytes.IndexFunc(line, func(r rune) bool {
+				return !unicode.IsSpace(r)
+			})
+			if i < 0 {
+				i = len(line)
+				pos.col -= lengthNL(line)
+			}
+			line = line[i:]
+			pos.col += i
+		}
+		if len(line) == 0 || line[0] != '"' {
+			// Non-quoted string field
+			i := bytes.IndexRune(line, r.Comma)
+			field := line
+			if i >= 0 {
+				field = field[:i]
+			} else {
+				field = field[:len(field)-lengthNL(field)]
+			}
+			// Check to make sure a quote does not appear in field.
+			if !r.LazyQuotes {
+				if j := bytes.IndexByte(field, '"'); j >= 0 {
+					col := pos.col + j
+					err = &ParseError{StartLine: recLine, Line: r.numLine, Column: col, Err: ErrBareQuote}
+					break parseField
+				}
+			}
+			r.recordBuffer = append(r.recordBuffer, field...)
+			r.fieldIndexes = append(r.fieldIndexes, len(r.recordBuffer))
+			r.fieldPositions = append(r.fieldPositions, pos)
+			if i >= 0 {
+				line = line[i+commaLen:]
+				pos.col += i + commaLen
+				continue parseField
+			}
+			break parseField
+		} else {
+			// Quoted string field
+			fieldPos := pos
+			line = line[quoteLen:]
+			pos.col += quoteLen
+			for {
+				i := bytes.IndexByte(line, '"')
+				if i >= 0 {
+					// Hit next quote.
+					r.recordBuffer = append(r.recordBuffer, line[:i]...)
+					line = line[i+quoteLen:]
+					pos.col += i + quoteLen
+					switch rn := nextRune(line); {
+					case rn == '"':
+						// `""` sequence (append quote).
+						r.recordBuffer = append(r.recordBuffer, '"')
+						line = line[quoteLen:]
+						pos.col += quoteLen
+					case rn == r.Comma:
+						// `",` sequence (end of field).
+						line = line[commaLen:]
+						pos.col += commaLen
+						r.fieldIndexes = append(r.fieldIndexes, len(r.recordBuffer))
+						r.fieldPositions = append(r.fieldPositions, fieldPos)
+						continue parseField
+					case lengthNL(line) == len(line):
+						// `"\n` sequence (end of line).
+						r.fieldIndexes = append(r.fieldIndexes, len(r.recordBuffer))
+						r.fieldPositions = append(r.fieldPositions, fieldPos)
+						break parseField
+					case r.LazyQuotes:
+						// `"` sequence (bare quote).
+						r.recordBuffer = append(r.recordBuffer, '"')
+					default:
+						// `"*` sequence (invalid non-escaped quote).
+						err = &ParseError{StartLine: recLine, Line: r.numLine, Column: pos.col - quoteLen, Err: ErrQuote}
+						break parseField
+					}
+				} else if len(line) > 0 {
+					// Hit end of line (copy all data so far).
+					r.recordBuffer = append(r.recordBuffer, line...)
+					if errRead != nil {
+						break parseField
+					}
+					pos.col += len(line)
+					line, errRead = r.readLine()
+					if len(line) > 0 {
+						pos.line++
+						pos.col = 1
+					}
+					if errRead == io.EOF {
+						errRead = nil
+					}
+				} else {
+					// Abrupt end of file (EOF or error).
+					if !r.LazyQuotes && errRead == nil {
+						err = &ParseError{StartLine: recLine, Line: pos.line, Column: pos.col, Err: ErrQuote}
+						break parseField
+					}
+					r.fieldIndexes = append(r.fieldIndexes, len(r.recordBuffer))
+					r.fieldPositions = append(r.fieldPositions, fieldPos)
+					break parseField
+				}
+			}
+		}
+	}
+	if err == nil {
+		err = errRead
+	}
+
+	// Create a single string and create slices out of it.
+	// This pins the memory of the fields together, but allocates once.
+	str := string(r.recordBuffer) // Convert to string once to batch allocations
+	dst = dst[:0]
+	if cap(dst) < len(r.fieldIndexes) {
+		dst = make([]string, len(r.fieldIndexes))
+	}
+	dst = dst[:len(r.fieldIndexes)]
+	var preIdx int
+	for i, idx := range r.fieldIndexes {
+		dst[i] = str[preIdx:idx]
+		preIdx = idx
+	}
+
+	// Check or update the expected fields per record.
+	if r.FieldsPerRecord > 0 {
+		if len(dst) != r.FieldsPerRecord && err == nil {
+			err = &ParseError{
+				StartLine: recLine,
+				Line:      recLine,
+				Column:    1,
+				Err:       ErrFieldCount,
+			}
+		}
+	} else if r.FieldsPerRecord == 0 {
+		r.FieldsPerRecord = len(dst)
+	}
+	return dst, err
+}
diff --git a/contrib/go/_std_1.18/src/encoding/csv/writer.go b/contrib/go/_std_1.19/src/encoding/csv/writer.go
index ac64b4d54c..ac64b4d54c 100644
--- a/contrib/go/_std_1.18/src/encoding/csv/writer.go
+++ b/contrib/go/_std_1.19/src/encoding/csv/writer.go
diff --git a/contrib/go/_std_1.19/src/encoding/encoding.go b/contrib/go/_std_1.19/src/encoding/encoding.go
new file mode 100644
index 0000000000..cc5a536996
--- /dev/null
+++ b/contrib/go/_std_1.19/src/encoding/encoding.go
@@ -0,0 +1,48 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package encoding defines interfaces shared by other packages that
+// convert data to and from byte-level and textual representations.
+// Packages that check for these interfaces include encoding/gob,
+// encoding/json, and encoding/xml. As a result, implementing an
+// interface once can make a type useful in multiple encodings.
+// Standard types that implement these interfaces include time.Time and net.IP.
+// The interfaces come in pairs that produce and consume encoded data.
+package encoding
+
+// BinaryMarshaler is the interface implemented by an object that can
+// marshal itself into a binary form.
+//
+// MarshalBinary encodes the receiver into a binary form and returns the result.
+type BinaryMarshaler interface {
+	MarshalBinary() (data []byte, err error)
+}
+
+// BinaryUnmarshaler is the interface implemented by an object that can
+// unmarshal a binary representation of itself.
+//
+// UnmarshalBinary must be able to decode the form generated by MarshalBinary.
+// UnmarshalBinary must copy the data if it wishes to retain the data
+// after returning.
+type BinaryUnmarshaler interface {
+	UnmarshalBinary(data []byte) error
+}
+
+// TextMarshaler is the interface implemented by an object that can
+// marshal itself into a textual form.
+//
+// MarshalText encodes the receiver into UTF-8-encoded text and returns the result.
+type TextMarshaler interface {
+	MarshalText() (text []byte, err error)
+}
+
+// TextUnmarshaler is the interface implemented by an object that can
+// unmarshal a textual representation of itself.
+//
+// UnmarshalText must be able to decode the form generated by MarshalText.
+// UnmarshalText must copy the text if it wishes to retain the text
+// after returning.
+type TextUnmarshaler interface {
+	UnmarshalText(text []byte) error
+}
diff --git a/contrib/go/_std_1.19/src/encoding/hex/hex.go b/contrib/go/_std_1.19/src/encoding/hex/hex.go
new file mode 100644
index 0000000000..375f583170
--- /dev/null
+++ b/contrib/go/_std_1.19/src/encoding/hex/hex.go
@@ -0,0 +1,335 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package hex implements hexadecimal encoding and decoding.
+package hex
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"strings"
+)
+
+const (
+	hextable        = "0123456789abcdef"
+	reverseHexTable = "" +
+		"\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" +
+		"\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" +
+		"\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" +
+		"\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\xff\xff\xff\xff\xff\xff" +
+		"\xff\x0a\x0b\x0c\x0d\x0e\x0f\xff\xff\xff\xff\xff\xff\xff\xff\xff" +
+		"\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" +
+		"\xff\x0a\x0b\x0c\x0d\x0e\x0f\xff\xff\xff\xff\xff\xff\xff\xff\xff" +
+		"\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" +
+		"\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" +
+		"\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" +
+		"\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" +
+		"\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" +
+		"\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" +
+		"\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" +
+		"\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" +
+		"\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff"
+)
+
+// EncodedLen returns the length of an encoding of n source bytes.
+// Specifically, it returns n * 2.
+func EncodedLen(n int) int { return n * 2 }
+
+// Encode encodes src into EncodedLen(len(src))
+// bytes of dst. As a convenience, it returns the number
+// of bytes written to dst, but this value is always EncodedLen(len(src)).
+// Encode implements hexadecimal encoding.
+func Encode(dst, src []byte) int {
+	j := 0
+	for _, v := range src {
+		dst[j] = hextable[v>>4]
+		dst[j+1] = hextable[v&0x0f]
+		j += 2
+	}
+	return len(src) * 2
+}
+
+// ErrLength reports an attempt to decode an odd-length input
+// using Decode or DecodeString.
+// The stream-based Decoder returns io.ErrUnexpectedEOF instead of ErrLength.
+var ErrLength = errors.New("encoding/hex: odd length hex string")
+
+// InvalidByteError values describe errors resulting from an invalid byte in a hex string.
+type InvalidByteError byte
+
+func (e InvalidByteError) Error() string {
+	return fmt.Sprintf("encoding/hex: invalid byte: %#U", rune(e))
+}
+
+// DecodedLen returns the length of a decoding of x source bytes.
+// Specifically, it returns x / 2.
+func DecodedLen(x int) int { return x / 2 }
+
+// Decode decodes src into DecodedLen(len(src)) bytes,
+// returning the actual number of bytes written to dst.
+//
+// Decode expects that src contains only hexadecimal
+// characters and that src has even length.
+// If the input is malformed, Decode returns the number
+// of bytes decoded before the error.
+func Decode(dst, src []byte) (int, error) {
+	i, j := 0, 1
+	for ; j < len(src); j += 2 {
+		p := src[j-1]
+		q := src[j]
+
+		a := reverseHexTable[p]
+		b := reverseHexTable[q]
+		if a > 0x0f {
+			return i, InvalidByteError(p)
+		}
+		if b > 0x0f {
+			return i, InvalidByteError(q)
+		}
+		dst[i] = (a << 4) | b
+		i++
+	}
+	if len(src)%2 == 1 {
+		// Check for invalid char before reporting bad length,
+		// since the invalid char (if present) is an earlier problem.
+		if reverseHexTable[src[j-1]] > 0x0f {
+			return i, InvalidByteError(src[j-1])
+		}
+		return i, ErrLength
+	}
+	return i, nil
+}
+
+// EncodeToString returns the hexadecimal encoding of src.
+func EncodeToString(src []byte) string {
+	dst := make([]byte, EncodedLen(len(src)))
+	Encode(dst, src)
+	return string(dst)
+}
+
+// DecodeString returns the bytes represented by the hexadecimal string s.
+//
+// DecodeString expects that src contains only hexadecimal
+// characters and that src has even length.
+// If the input is malformed, DecodeString returns
+// the bytes decoded before the error.
+func DecodeString(s string) ([]byte, error) {
+	src := []byte(s)
+	// We can use the source slice itself as the destination
+	// because the decode loop increments by one and then the 'seen' byte is not used anymore.
+	n, err := Decode(src, src)
+	return src[:n], err
+}
+
+// Dump returns a string that contains a hex dump of the given data. The format
+// of the hex dump matches the output of `hexdump -C` on the command line.
+func Dump(data []byte) string {
+	if len(data) == 0 {
+		return ""
+	}
+
+	var buf strings.Builder
+	// Dumper will write 79 bytes per complete 16 byte chunk, and at least
+	// 64 bytes for whatever remains. Round the allocation up, since only a
+	// maximum of 15 bytes will be wasted.
+	buf.Grow((1 + ((len(data) - 1) / 16)) * 79)
+
+	dumper := Dumper(&buf)
+	dumper.Write(data)
+	dumper.Close()
+	return buf.String()
+}
+
+// bufferSize is the number of hexadecimal characters to buffer in encoder and decoder.
+const bufferSize = 1024
+
+type encoder struct {
+	w   io.Writer
+	err error
+	out [bufferSize]byte // output buffer
+}
+
+// NewEncoder returns an io.Writer that writes lowercase hexadecimal characters to w.
+func NewEncoder(w io.Writer) io.Writer {
+	return &encoder{w: w}
+}
+
+func (e *encoder) Write(p []byte) (n int, err error) {
+	for len(p) > 0 && e.err == nil {
+		chunkSize := bufferSize / 2
+		if len(p) < chunkSize {
+			chunkSize = len(p)
+		}
+
+		var written int
+		encoded := Encode(e.out[:], p[:chunkSize])
+		written, e.err = e.w.Write(e.out[:encoded])
+		n += written / 2
+		p = p[chunkSize:]
+	}
+	return n, e.err
+}
+
+type decoder struct {
+	r   io.Reader
+	err error
+	in  []byte           // input buffer (encoded form)
+	arr [bufferSize]byte // backing array for in
+}
+
+// NewDecoder returns an io.Reader that decodes hexadecimal characters from r.
+// NewDecoder expects that r contain only an even number of hexadecimal characters.
+func NewDecoder(r io.Reader) io.Reader {
+	return &decoder{r: r}
+}
+
+func (d *decoder) Read(p []byte) (n int, err error) {
+	// Fill internal buffer with sufficient bytes to decode
+	if len(d.in) < 2 && d.err == nil {
+		var numCopy, numRead int
+		numCopy = copy(d.arr[:], d.in) // Copies either 0 or 1 bytes
+		numRead, d.err = d.r.Read(d.arr[numCopy:])
+		d.in = d.arr[:numCopy+numRead]
+		if d.err == io.EOF && len(d.in)%2 != 0 {
+
+			if a := reverseHexTable[d.in[len(d.in)-1]]; a > 0x0f {
+				d.err = InvalidByteError(d.in[len(d.in)-1])
+			} else {
+				d.err = io.ErrUnexpectedEOF
+			}
+		}
+	}
+
+	// Decode internal buffer into output buffer
+	if numAvail := len(d.in) / 2; len(p) > numAvail {
+		p = p[:numAvail]
+	}
+	numDec, err := Decode(p, d.in[:len(p)*2])
+	d.in = d.in[2*numDec:]
+	if err != nil {
+		d.in, d.err = nil, err // Decode error; discard input remainder
+	}
+
+	if len(d.in) < 2 {
+		return numDec, d.err // Only expose errors when buffer fully consumed
+	}
+	return numDec, nil
+}
+
+// Dumper returns a WriteCloser that writes a hex dump of all written data to
+// w. The format of the dump matches the output of `hexdump -C` on the command
+// line.
+func Dumper(w io.Writer) io.WriteCloser {
+	return &dumper{w: w}
+}
+
+type dumper struct {
+	w          io.Writer
+	rightChars [18]byte
+	buf        [14]byte
+	used       int  // number of bytes in the current line
+	n          uint // number of bytes, total
+	closed     bool
+}
+
+func toChar(b byte) byte {
+	if b < 32 || b > 126 {
+		return '.'
+	}
+	return b
+}
+
+func (h *dumper) Write(data []byte) (n int, err error) {
+	if h.closed {
+		return 0, errors.New("encoding/hex: dumper closed")
+	}
+
+	// Output lines look like:
+	// 00000010  2e 2f 30 31 32 33 34 35  36 37 38 39 3a 3b 3c 3d  |./0123456789:;<=|
+	// ^ offset                          ^ extra space              ^ ASCII of line.
+	for i := range data {
+		if h.used == 0 {
+			// At the beginning of a line we print the current
+			// offset in hex.
+			h.buf[0] = byte(h.n >> 24)
+			h.buf[1] = byte(h.n >> 16)
+			h.buf[2] = byte(h.n >> 8)
+			h.buf[3] = byte(h.n)
+			Encode(h.buf[4:], h.buf[:4])
+			h.buf[12] = ' '
+			h.buf[13] = ' '
+			_, err = h.w.Write(h.buf[4:])
+			if err != nil {
+				return
+			}
+		}
+		Encode(h.buf[:], data[i:i+1])
+		h.buf[2] = ' '
+		l := 3
+		if h.used == 7 {
+			// There's an additional space after the 8th byte.
+			h.buf[3] = ' '
+			l = 4
+		} else if h.used == 15 {
+			// At the end of the line there's an extra space and
+			// the bar for the right column.
+			h.buf[3] = ' '
+			h.buf[4] = '|'
+			l = 5
+		}
+		_, err = h.w.Write(h.buf[:l])
+		if err != nil {
+			return
+		}
+		n++
+		h.rightChars[h.used] = toChar(data[i])
+		h.used++
+		h.n++
+		if h.used == 16 {
+			h.rightChars[16] = '|'
+			h.rightChars[17] = '\n'
+			_, err = h.w.Write(h.rightChars[:])
+			if err != nil {
+				return
+			}
+			h.used = 0
+		}
+	}
+	return
+}
+
+func (h *dumper) Close() (err error) {
+	// See the comments in Write() for the details of this format.
+	if h.closed {
+		return
+	}
+	h.closed = true
+	if h.used == 0 {
+		return
+	}
+	h.buf[0] = ' '
+	h.buf[1] = ' '
+	h.buf[2] = ' '
+	h.buf[3] = ' '
+	h.buf[4] = '|'
+	nBytes := h.used
+	for h.used < 16 {
+		l := 3
+		if h.used == 7 {
+			l = 4
+		} else if h.used == 15 {
+			l = 5
+		}
+		_, err = h.w.Write(h.buf[:l])
+		if err != nil {
+			return
+		}
+		h.used++
+	}
+	h.rightChars[nBytes] = '|'
+	h.rightChars[nBytes+1] = '\n'
+	_, err = h.w.Write(h.rightChars[:nBytes+2])
+	return
+}
diff --git a/contrib/go/_std_1.19/src/encoding/pem/pem.go b/contrib/go/_std_1.19/src/encoding/pem/pem.go
new file mode 100644
index 0000000000..d26e4c8399
--- /dev/null
+++ b/contrib/go/_std_1.19/src/encoding/pem/pem.go
@@ -0,0 +1,316 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package pem implements the PEM data encoding, which originated in Privacy
+// Enhanced Mail. The most common use of PEM encoding today is in TLS keys and
+// certificates. See RFC 1421.
+package pem
+
+import (
+	"bytes"
+	"encoding/base64"
+	"errors"
+	"io"
+	"sort"
+	"strings"
+)
+
+// A Block represents a PEM encoded structure.
+//
+// The encoded form is:
+//
+//	-----BEGIN Type-----
+//	Headers
+//	base64-encoded Bytes
+//	-----END Type-----
+//
+// where Headers is a possibly empty sequence of Key: Value lines.
+type Block struct {
+	Type    string            // The type, taken from the preamble (i.e. "RSA PRIVATE KEY").
+	Headers map[string]string // Optional headers.
+	Bytes   []byte            // The decoded bytes of the contents. Typically a DER encoded ASN.1 structure.
+}
+
+// getLine results the first \r\n or \n delineated line from the given byte
+// array. The line does not include trailing whitespace or the trailing new
+// line bytes. The remainder of the byte array (also not including the new line
+// bytes) is also returned and this will always be smaller than the original
+// argument.
+func getLine(data []byte) (line, rest []byte) {
+	i := bytes.IndexByte(data, '\n')
+	var j int
+	if i < 0 {
+		i = len(data)
+		j = i
+	} else {
+		j = i + 1
+		if i > 0 && data[i-1] == '\r' {
+			i--
+		}
+	}
+	return bytes.TrimRight(data[0:i], " \t"), data[j:]
+}
+
+// removeSpacesAndTabs returns a copy of its input with all spaces and tabs
+// removed, if there were any. Otherwise, the input is returned unchanged.
+//
+// The base64 decoder already skips newline characters, so we don't need to
+// filter them out here.
+func removeSpacesAndTabs(data []byte) []byte {
+	if !bytes.ContainsAny(data, " \t") {
+		// Fast path; most base64 data within PEM contains newlines, but
+		// no spaces nor tabs. Skip the extra alloc and work.
+		return data
+	}
+	result := make([]byte, len(data))
+	n := 0
+
+	for _, b := range data {
+		if b == ' ' || b == '\t' {
+			continue
+		}
+		result[n] = b
+		n++
+	}
+
+	return result[0:n]
+}
+
+var pemStart = []byte("\n-----BEGIN ")
+var pemEnd = []byte("\n-----END ")
+var pemEndOfLine = []byte("-----")
+var colon = []byte(":")
+
+// Decode will find the next PEM formatted block (certificate, private key
+// etc) in the input. It returns that block and the remainder of the input. If
+// no PEM data is found, p is nil and the whole of the input is returned in
+// rest.
+func Decode(data []byte) (p *Block, rest []byte) {
+	// pemStart begins with a newline. However, at the very beginning of
+	// the byte array, we'll accept the start string without it.
+	rest = data
+	for {
+		if bytes.HasPrefix(rest, pemStart[1:]) {
+			rest = rest[len(pemStart)-1:]
+		} else if _, after, ok := bytes.Cut(rest, pemStart); ok {
+			rest = after
+		} else {
+			return nil, data
+		}
+
+		var typeLine []byte
+		typeLine, rest = getLine(rest)
+		if !bytes.HasSuffix(typeLine, pemEndOfLine) {
+			continue
+		}
+		typeLine = typeLine[0 : len(typeLine)-len(pemEndOfLine)]
+
+		p = &Block{
+			Headers: make(map[string]string),
+			Type:    string(typeLine),
+		}
+
+		for {
+			// This loop terminates because getLine's second result is
+			// always smaller than its argument.
+			if len(rest) == 0 {
+				return nil, data
+			}
+			line, next := getLine(rest)
+
+			key, val, ok := bytes.Cut(line, colon)
+			if !ok {
+				break
+			}
+
+			// TODO(agl): need to cope with values that spread across lines.
+			key = bytes.TrimSpace(key)
+			val = bytes.TrimSpace(val)
+			p.Headers[string(key)] = string(val)
+			rest = next
+		}
+
+		var endIndex, endTrailerIndex int
+
+		// If there were no headers, the END line might occur
+		// immediately, without a leading newline.
+		if len(p.Headers) == 0 && bytes.HasPrefix(rest, pemEnd[1:]) {
+			endIndex = 0
+			endTrailerIndex = len(pemEnd) - 1
+		} else {
+			endIndex = bytes.Index(rest, pemEnd)
+			endTrailerIndex = endIndex + len(pemEnd)
+		}
+
+		if endIndex < 0 {
+			continue
+		}
+
+		// After the "-----" of the ending line, there should be the same type
+		// and then a final five dashes.
+		endTrailer := rest[endTrailerIndex:]
+		endTrailerLen := len(typeLine) + len(pemEndOfLine)
+		if len(endTrailer) < endTrailerLen {
+			continue
+		}
+
+		restOfEndLine := endTrailer[endTrailerLen:]
+		endTrailer = endTrailer[:endTrailerLen]
+		if !bytes.HasPrefix(endTrailer, typeLine) ||
+			!bytes.HasSuffix(endTrailer, pemEndOfLine) {
+			continue
+		}
+
+		// The line must end with only whitespace.
+		if s, _ := getLine(restOfEndLine); len(s) != 0 {
+			continue
+		}
+
+		base64Data := removeSpacesAndTabs(rest[:endIndex])
+		p.Bytes = make([]byte, base64.StdEncoding.DecodedLen(len(base64Data)))
+		n, err := base64.StdEncoding.Decode(p.Bytes, base64Data)
+		if err != nil {
+			continue
+		}
+		p.Bytes = p.Bytes[:n]
+
+		// the -1 is because we might have only matched pemEnd without the
+		// leading newline if the PEM block was empty.
+		_, rest = getLine(rest[endIndex+len(pemEnd)-1:])
+		return p, rest
+	}
+}
+
+const pemLineLength = 64
+
+type lineBreaker struct {
+	line [pemLineLength]byte
+	used int
+	out  io.Writer
+}
+
+var nl = []byte{'\n'}
+
+func (l *lineBreaker) Write(b []byte) (n int, err error) {
+	if l.used+len(b) < pemLineLength {
+		copy(l.line[l.used:], b)
+		l.used += len(b)
+		return len(b), nil
+	}
+
+	n, err = l.out.Write(l.line[0:l.used])
+	if err != nil {
+		return
+	}
+	excess := pemLineLength - l.used
+	l.used = 0
+
+	n, err = l.out.Write(b[0:excess])
+	if err != nil {
+		return
+	}
+
+	n, err = l.out.Write(nl)
+	if err != nil {
+		return
+	}
+
+	return l.Write(b[excess:])
+}
+
+func (l *lineBreaker) Close() (err error) {
+	if l.used > 0 {
+		_, err = l.out.Write(l.line[0:l.used])
+		if err != nil {
+			return
+		}
+		_, err = l.out.Write(nl)
+	}
+
+	return
+}
+
+func writeHeader(out io.Writer, k, v string) error {
+	_, err := out.Write([]byte(k + ": " + v + "\n"))
+	return err
+}
+
+// Encode writes the PEM encoding of b to out.
+func Encode(out io.Writer, b *Block) error {
+	// Check for invalid block before writing any output.
+	for k := range b.Headers {
+		if strings.Contains(k, ":") {
+			return errors.New("pem: cannot encode a header key that contains a colon")
+		}
+	}
+
+	// All errors below are relayed from underlying io.Writer,
+	// so it is now safe to write data.
+
+	if _, err := out.Write(pemStart[1:]); err != nil {
+		return err
+	}
+	if _, err := out.Write([]byte(b.Type + "-----\n")); err != nil {
+		return err
+	}
+
+	if len(b.Headers) > 0 {
+		const procType = "Proc-Type"
+		h := make([]string, 0, len(b.Headers))
+		hasProcType := false
+		for k := range b.Headers {
+			if k == procType {
+				hasProcType = true
+				continue
+			}
+			h = append(h, k)
+		}
+		// The Proc-Type header must be written first.
+		// See RFC 1421, section 4.6.1.1
+		if hasProcType {
+			if err := writeHeader(out, procType, b.Headers[procType]); err != nil {
+				return err
+			}
+		}
+		// For consistency of output, write other headers sorted by key.
+		sort.Strings(h)
+		for _, k := range h {
+			if err := writeHeader(out, k, b.Headers[k]); err != nil {
+				return err
+			}
+		}
+		if _, err := out.Write(nl); err != nil {
+			return err
+		}
+	}
+
+	var breaker lineBreaker
+	breaker.out = out
+
+	b64 := base64.NewEncoder(base64.StdEncoding, &breaker)
+	if _, err := b64.Write(b.Bytes); err != nil {
+		return err
+	}
+	b64.Close()
+	breaker.Close()
+
+	if _, err := out.Write(pemEnd[1:]); err != nil {
+		return err
+	}
+	_, err := out.Write([]byte(b.Type + "-----\n"))
+	return err
+}
+
+// EncodeToMemory returns the PEM encoding of b.
+//
+// If b has invalid headers and cannot be encoded,
+// EncodeToMemory returns nil. If it is important to
+// report details about this error case, use Encode instead.
+func EncodeToMemory(b *Block) []byte {
+	var buf bytes.Buffer
+	if err := Encode(&buf, b); err != nil {
+		return nil
+	}
+	return buf.Bytes()
+}
diff --git a/contrib/go/_std_1.18/src/errors/errors.go b/contrib/go/_std_1.19/src/errors/errors.go
index f2fabacd4e..f2fabacd4e 100644
--- a/contrib/go/_std_1.18/src/errors/errors.go
+++ b/contrib/go/_std_1.19/src/errors/errors.go
diff --git a/contrib/go/_std_1.18/src/errors/wrap.go b/contrib/go/_std_1.19/src/errors/wrap.go
index 263ae16b48..263ae16b48 100644
--- a/contrib/go/_std_1.18/src/errors/wrap.go
+++ b/contrib/go/_std_1.19/src/errors/wrap.go
diff --git a/contrib/go/_std_1.19/src/flag/flag.go b/contrib/go/_std_1.19/src/flag/flag.go
new file mode 100644
index 0000000000..9abf8d769e
--- /dev/null
+++ b/contrib/go/_std_1.19/src/flag/flag.go
@@ -0,0 +1,1180 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package flag implements command-line flag parsing.
+
+# Usage
+
+Define flags using flag.String(), Bool(), Int(), etc.
+
+This declares an integer flag, -n, stored in the pointer nFlag, with type *int:
+
+	import "flag"
+	var nFlag = flag.Int("n", 1234, "help message for flag n")
+
+If you like, you can bind the flag to a variable using the Var() functions.
+
+	var flagvar int
+	func init() {
+		flag.IntVar(&flagvar, "flagname", 1234, "help message for flagname")
+	}
+
+Or you can create custom flags that satisfy the Value interface (with
+pointer receivers) and couple them to flag parsing by
+
+	flag.Var(&flagVal, "name", "help message for flagname")
+
+For such flags, the default value is just the initial value of the variable.
+
+After all flags are defined, call
+
+	flag.Parse()
+
+to parse the command line into the defined flags.
+
+Flags may then be used directly. If you're using the flags themselves,
+they are all pointers; if you bind to variables, they're values.
+
+	fmt.Println("ip has value ", *ip)
+	fmt.Println("flagvar has value ", flagvar)
+
+After parsing, the arguments following the flags are available as the
+slice flag.Args() or individually as flag.Arg(i).
+The arguments are indexed from 0 through flag.NArg()-1.
+
+# Command line flag syntax
+
+The following forms are permitted:
+
+	-flag
+	--flag   // double dashes are also permitted
+	-flag=x
+	-flag x  // non-boolean flags only
+
+One or two dashes may be used; they are equivalent.
+The last form is not permitted for boolean flags because the
+meaning of the command
+
+	cmd -x *
+
+where * is a Unix shell wildcard, will change if there is a file
+called 0, false, etc. You must use the -flag=false form to turn
+off a boolean flag.
+
+Flag parsing stops just before the first non-flag argument
+("-" is a non-flag argument) or after the terminator "--".
+
+Integer flags accept 1234, 0664, 0x1234 and may be negative.
+Boolean flags may be:
+
+	1, 0, t, f, T, F, true, false, TRUE, FALSE, True, False
+
+Duration flags accept any input valid for time.ParseDuration.
+
+The default set of command-line flags is controlled by
+top-level functions.  The FlagSet type allows one to define
+independent sets of flags, such as to implement subcommands
+in a command-line interface. The methods of FlagSet are
+analogous to the top-level functions for the command-line
+flag set.
+*/
+package flag
+
+import (
+	"encoding"
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"reflect"
+	"sort"
+	"strconv"
+	"strings"
+	"time"
+)
+
+// ErrHelp is the error returned if the -help or -h flag is invoked
+// but no such flag is defined.
+var ErrHelp = errors.New("flag: help requested")
+
+// errParse is returned by Set if a flag's value fails to parse, such as with an invalid integer for Int.
+// It then gets wrapped through failf to provide more information.
+var errParse = errors.New("parse error")
+
+// errRange is returned by Set if a flag's value is out of range.
+// It then gets wrapped through failf to provide more information.
+var errRange = errors.New("value out of range")
+
+func numError(err error) error {
+	ne, ok := err.(*strconv.NumError)
+	if !ok {
+		return err
+	}
+	if ne.Err == strconv.ErrSyntax {
+		return errParse
+	}
+	if ne.Err == strconv.ErrRange {
+		return errRange
+	}
+	return err
+}
+
+// -- bool Value
+type boolValue bool
+
+func newBoolValue(val bool, p *bool) *boolValue {
+	*p = val
+	return (*boolValue)(p)
+}
+
+func (b *boolValue) Set(s string) error {
+	v, err := strconv.ParseBool(s)
+	if err != nil {
+		err = errParse
+	}
+	*b = boolValue(v)
+	return err
+}
+
+func (b *boolValue) Get() any { return bool(*b) }
+
+func (b *boolValue) String() string { return strconv.FormatBool(bool(*b)) }
+
+func (b *boolValue) IsBoolFlag() bool { return true }
+
+// optional interface to indicate boolean flags that can be
+// supplied without "=value" text
+type boolFlag interface {
+	Value
+	IsBoolFlag() bool
+}
+
+// -- int Value
+type intValue int
+
+func newIntValue(val int, p *int) *intValue {
+	*p = val
+	return (*intValue)(p)
+}
+
+func (i *intValue) Set(s string) error {
+	v, err := strconv.ParseInt(s, 0, strconv.IntSize)
+	if err != nil {
+		err = numError(err)
+	}
+	*i = intValue(v)
+	return err
+}
+
+func (i *intValue) Get() any { return int(*i) }
+
+func (i *intValue) String() string { return strconv.Itoa(int(*i)) }
+
+// -- int64 Value
+type int64Value int64
+
+func newInt64Value(val int64, p *int64) *int64Value {
+	*p = val
+	return (*int64Value)(p)
+}
+
+func (i *int64Value) Set(s string) error {
+	v, err := strconv.ParseInt(s, 0, 64)
+	if err != nil {
+		err = numError(err)
+	}
+	*i = int64Value(v)
+	return err
+}
+
+func (i *int64Value) Get() any { return int64(*i) }
+
+func (i *int64Value) String() string { return strconv.FormatInt(int64(*i), 10) }
+
+// -- uint Value
+type uintValue uint
+
+func newUintValue(val uint, p *uint) *uintValue {
+	*p = val
+	return (*uintValue)(p)
+}
+
+func (i *uintValue) Set(s string) error {
+	v, err := strconv.ParseUint(s, 0, strconv.IntSize)
+	if err != nil {
+		err = numError(err)
+	}
+	*i = uintValue(v)
+	return err
+}
+
+func (i *uintValue) Get() any { return uint(*i) }
+
+func (i *uintValue) String() string { return strconv.FormatUint(uint64(*i), 10) }
+
+// -- uint64 Value
+type uint64Value uint64
+
+func newUint64Value(val uint64, p *uint64) *uint64Value {
+	*p = val
+	return (*uint64Value)(p)
+}
+
+func (i *uint64Value) Set(s string) error {
+	v, err := strconv.ParseUint(s, 0, 64)
+	if err != nil {
+		err = numError(err)
+	}
+	*i = uint64Value(v)
+	return err
+}
+
+func (i *uint64Value) Get() any { return uint64(*i) }
+
+func (i *uint64Value) String() string { return strconv.FormatUint(uint64(*i), 10) }
+
+// -- string Value
+type stringValue string
+
+func newStringValue(val string, p *string) *stringValue {
+	*p = val
+	return (*stringValue)(p)
+}
+
+func (s *stringValue) Set(val string) error {
+	*s = stringValue(val)
+	return nil
+}
+
+func (s *stringValue) Get() any { return string(*s) }
+
+func (s *stringValue) String() string { return string(*s) }
+
+// -- float64 Value
+type float64Value float64
+
+func newFloat64Value(val float64, p *float64) *float64Value {
+	*p = val
+	return (*float64Value)(p)
+}
+
+func (f *float64Value) Set(s string) error {
+	v, err := strconv.ParseFloat(s, 64)
+	if err != nil {
+		err = numError(err)
+	}
+	*f = float64Value(v)
+	return err
+}
+
+func (f *float64Value) Get() any { return float64(*f) }
+
+func (f *float64Value) String() string { return strconv.FormatFloat(float64(*f), 'g', -1, 64) }
+
+// -- time.Duration Value
+type durationValue time.Duration
+
+func newDurationValue(val time.Duration, p *time.Duration) *durationValue {
+	*p = val
+	return (*durationValue)(p)
+}
+
+func (d *durationValue) Set(s string) error {
+	v, err := time.ParseDuration(s)
+	if err != nil {
+		err = errParse
+	}
+	*d = durationValue(v)
+	return err
+}
+
+func (d *durationValue) Get() any { return time.Duration(*d) }
+
+func (d *durationValue) String() string { return (*time.Duration)(d).String() }
+
+// -- encoding.TextUnmarshaler Value
+type textValue struct{ p encoding.TextUnmarshaler }
+
+func newTextValue(val encoding.TextMarshaler, p encoding.TextUnmarshaler) textValue {
+	ptrVal := reflect.ValueOf(p)
+	if ptrVal.Kind() != reflect.Ptr {
+		panic("variable value type must be a pointer")
+	}
+	defVal := reflect.ValueOf(val)
+	if defVal.Kind() == reflect.Ptr {
+		defVal = defVal.Elem()
+	}
+	if defVal.Type() != ptrVal.Type().Elem() {
+		panic(fmt.Sprintf("default type does not match variable type: %v != %v", defVal.Type(), ptrVal.Type().Elem()))
+	}
+	ptrVal.Elem().Set(defVal)
+	return textValue{p}
+}
+
+func (v textValue) Set(s string) error {
+	return v.p.UnmarshalText([]byte(s))
+}
+
+func (v textValue) Get() interface{} {
+	return v.p
+}
+
+func (v textValue) String() string {
+	if m, ok := v.p.(encoding.TextMarshaler); ok {
+		if b, err := m.MarshalText(); err == nil {
+			return string(b)
+		}
+	}
+	return ""
+}
+
+// -- func Value
+type funcValue func(string) error
+
+func (f funcValue) Set(s string) error { return f(s) }
+
+func (f funcValue) String() string { return "" }
+
+// Value is the interface to the dynamic value stored in a flag.
+// (The default value is represented as a string.)
+//
+// If a Value has an IsBoolFlag() bool method returning true,
+// the command-line parser makes -name equivalent to -name=true
+// rather than using the next command-line argument.
+//
+// Set is called once, in command line order, for each flag present.
+// The flag package may call the String method with a zero-valued receiver,
+// such as a nil pointer.
+type Value interface {
+	String() string
+	Set(string) error
+}
+
+// Getter is an interface that allows the contents of a Value to be retrieved.
+// It wraps the Value interface, rather than being part of it, because it
+// appeared after Go 1 and its compatibility rules. All Value types provided
+// by this package satisfy the Getter interface, except the type used by Func.
+type Getter interface {
+	Value
+	Get() any
+}
+
+// ErrorHandling defines how FlagSet.Parse behaves if the parse fails.
+type ErrorHandling int
+
+// These constants cause FlagSet.Parse to behave as described if the parse fails.
+const (
+	ContinueOnError ErrorHandling = iota // Return a descriptive error.
+	ExitOnError                          // Call os.Exit(2) or for -h/-help Exit(0).
+	PanicOnError                         // Call panic with a descriptive error.
+)
+
+// A FlagSet represents a set of defined flags. The zero value of a FlagSet
+// has no name and has ContinueOnError error handling.
+//
+// Flag names must be unique within a FlagSet. An attempt to define a flag whose
+// name is already in use will cause a panic.
+type FlagSet struct {
+	// Usage is the function called when an error occurs while parsing flags.
+	// The field is a function (not a method) that may be changed to point to
+	// a custom error handler. What happens after Usage is called depends
+	// on the ErrorHandling setting; for the command line, this defaults
+	// to ExitOnError, which exits the program after calling Usage.
+	Usage func()
+
+	name          string
+	parsed        bool
+	actual        map[string]*Flag
+	formal        map[string]*Flag
+	args          []string // arguments after flags
+	errorHandling ErrorHandling
+	output        io.Writer // nil means stderr; use Output() accessor
+}
+
+// A Flag represents the state of a flag.
+type Flag struct {
+	Name     string // name as it appears on command line
+	Usage    string // help message
+	Value    Value  // value as set
+	DefValue string // default value (as text); for usage message
+}
+
+// sortFlags returns the flags as a slice in lexicographical sorted order.
+func sortFlags(flags map[string]*Flag) []*Flag {
+	result := make([]*Flag, len(flags))
+	i := 0
+	for _, f := range flags {
+		result[i] = f
+		i++
+	}
+	sort.Slice(result, func(i, j int) bool {
+		return result[i].Name < result[j].Name
+	})
+	return result
+}
+
+// Output returns the destination for usage and error messages. os.Stderr is returned if
+// output was not set or was set to nil.
+func (f *FlagSet) Output() io.Writer {
+	if f.output == nil {
+		return os.Stderr
+	}
+	return f.output
+}
+
+// Name returns the name of the flag set.
+func (f *FlagSet) Name() string {
+	return f.name
+}
+
+// ErrorHandling returns the error handling behavior of the flag set.
+func (f *FlagSet) ErrorHandling() ErrorHandling {
+	return f.errorHandling
+}
+
+// SetOutput sets the destination for usage and error messages.
+// If output is nil, os.Stderr is used.
+func (f *FlagSet) SetOutput(output io.Writer) {
+	f.output = output
+}
+
+// VisitAll visits the flags in lexicographical order, calling fn for each.
+// It visits all flags, even those not set.
+func (f *FlagSet) VisitAll(fn func(*Flag)) {
+	for _, flag := range sortFlags(f.formal) {
+		fn(flag)
+	}
+}
+
+// VisitAll visits the command-line flags in lexicographical order, calling
+// fn for each. It visits all flags, even those not set.
+func VisitAll(fn func(*Flag)) {
+	CommandLine.VisitAll(fn)
+}
+
+// Visit visits the flags in lexicographical order, calling fn for each.
+// It visits only those flags that have been set.
+func (f *FlagSet) Visit(fn func(*Flag)) {
+	for _, flag := range sortFlags(f.actual) {
+		fn(flag)
+	}
+}
+
+// Visit visits the command-line flags in lexicographical order, calling fn
+// for each. It visits only those flags that have been set.
+func Visit(fn func(*Flag)) {
+	CommandLine.Visit(fn)
+}
+
+// Lookup returns the Flag structure of the named flag, returning nil if none exists.
+func (f *FlagSet) Lookup(name string) *Flag {
+	return f.formal[name]
+}
+
+// Lookup returns the Flag structure of the named command-line flag,
+// returning nil if none exists.
+func Lookup(name string) *Flag {
+	return CommandLine.formal[name]
+}
+
+// Set sets the value of the named flag.
+func (f *FlagSet) Set(name, value string) error {
+	flag, ok := f.formal[name]
+	if !ok {
+		return fmt.Errorf("no such flag -%v", name)
+	}
+	err := flag.Value.Set(value)
+	if err != nil {
+		return err
+	}
+	if f.actual == nil {
+		f.actual = make(map[string]*Flag)
+	}
+	f.actual[name] = flag
+	return nil
+}
+
+// Set sets the value of the named command-line flag.
+func Set(name, value string) error {
+	return CommandLine.Set(name, value)
+}
+
+// isZeroValue determines whether the string represents the zero
+// value for a flag.
+func isZeroValue(flag *Flag, value string) (ok bool, err error) {
+	// Build a zero value of the flag's Value type, and see if the
+	// result of calling its String method equals the value passed in.
+	// This works unless the Value type is itself an interface type.
+	typ := reflect.TypeOf(flag.Value)
+	var z reflect.Value
+	if typ.Kind() == reflect.Pointer {
+		z = reflect.New(typ.Elem())
+	} else {
+		z = reflect.Zero(typ)
+	}
+	// Catch panics calling the String method, which shouldn't prevent the
+	// usage message from being printed, but that we should report to the
+	// user so that they know to fix their code.
+	defer func() {
+		if e := recover(); e != nil {
+			if typ.Kind() == reflect.Pointer {
+				typ = typ.Elem()
+			}
+			err = fmt.Errorf("panic calling String method on zero %v for flag %s: %v", typ, flag.Name, e)
+		}
+	}()
+	return value == z.Interface().(Value).String(), nil
+}
+
+// UnquoteUsage extracts a back-quoted name from the usage
+// string for a flag and returns it and the un-quoted usage.
+// Given "a `name` to show" it returns ("name", "a name to show").
+// If there are no back quotes, the name is an educated guess of the
+// type of the flag's value, or the empty string if the flag is boolean.
+func UnquoteUsage(flag *Flag) (name string, usage string) {
+	// Look for a back-quoted name, but avoid the strings package.
+	usage = flag.Usage
+	for i := 0; i < len(usage); i++ {
+		if usage[i] == '`' {
+			for j := i + 1; j < len(usage); j++ {
+				if usage[j] == '`' {
+					name = usage[i+1 : j]
+					usage = usage[:i] + name + usage[j+1:]
+					return name, usage
+				}
+			}
+			break // Only one back quote; use type name.
+		}
+	}
+	// No explicit name, so use type if we can find one.
+	name = "value"
+	switch flag.Value.(type) {
+	case boolFlag:
+		name = ""
+	case *durationValue:
+		name = "duration"
+	case *float64Value:
+		name = "float"
+	case *intValue, *int64Value:
+		name = "int"
+	case *stringValue:
+		name = "string"
+	case *uintValue, *uint64Value:
+		name = "uint"
+	}
+	return
+}
+
+// PrintDefaults prints, to standard error unless configured otherwise, the
+// default values of all defined command-line flags in the set. See the
+// documentation for the global function PrintDefaults for more information.
+func (f *FlagSet) PrintDefaults() {
+	var isZeroValueErrs []error
+	f.VisitAll(func(flag *Flag) {
+		var b strings.Builder
+		fmt.Fprintf(&b, "  -%s", flag.Name) // Two spaces before -; see next two comments.
+		name, usage := UnquoteUsage(flag)
+		if len(name) > 0 {
+			b.WriteString(" ")
+			b.WriteString(name)
+		}
+		// Boolean flags of one ASCII letter are so common we
+		// treat them specially, putting their usage on the same line.
+		if b.Len() <= 4 { // space, space, '-', 'x'.
+			b.WriteString("\t")
+		} else {
+			// Four spaces before the tab triggers good alignment
+			// for both 4- and 8-space tab stops.
+			b.WriteString("\n    \t")
+		}
+		b.WriteString(strings.ReplaceAll(usage, "\n", "\n    \t"))
+
+		// Print the default value only if it differs to the zero value
+		// for this flag type.
+		if isZero, err := isZeroValue(flag, flag.DefValue); err != nil {
+			isZeroValueErrs = append(isZeroValueErrs, err)
+		} else if !isZero {
+			if _, ok := flag.Value.(*stringValue); ok {
+				// put quotes on the value
+				fmt.Fprintf(&b, " (default %q)", flag.DefValue)
+			} else {
+				fmt.Fprintf(&b, " (default %v)", flag.DefValue)
+			}
+		}
+		fmt.Fprint(f.Output(), b.String(), "\n")
+	})
+	// If calling String on any zero flag.Values triggered a panic, print
+	// the messages after the full set of defaults so that the programmer
+	// knows to fix the panic.
+	if errs := isZeroValueErrs; len(errs) > 0 {
+		fmt.Fprintln(f.Output())
+		for _, err := range errs {
+			fmt.Fprintln(f.Output(), err)
+		}
+	}
+}
+
+// PrintDefaults prints, to standard error unless configured otherwise,
+// a usage message showing the default settings of all defined
+// command-line flags.
+// For an integer valued flag x, the default output has the form
+//
+//	-x int
+//		usage-message-for-x (default 7)
+//
+// The usage message will appear on a separate line for anything but
+// a bool flag with a one-byte name. For bool flags, the type is
+// omitted and if the flag name is one byte the usage message appears
+// on the same line. The parenthetical default is omitted if the
+// default is the zero value for the type. The listed type, here int,
+// can be changed by placing a back-quoted name in the flag's usage
+// string; the first such item in the message is taken to be a parameter
+// name to show in the message and the back quotes are stripped from
+// the message when displayed. For instance, given
+//
+//	flag.String("I", "", "search `directory` for include files")
+//
+// the output will be
+//
+//	-I directory
+//		search directory for include files.
+//
+// To change the destination for flag messages, call CommandLine.SetOutput.
+func PrintDefaults() {
+	CommandLine.PrintDefaults()
+}
+
+// defaultUsage is the default function to print a usage message.
+func (f *FlagSet) defaultUsage() {
+	if f.name == "" {
+		fmt.Fprintf(f.Output(), "Usage:\n")
+	} else {
+		fmt.Fprintf(f.Output(), "Usage of %s:\n", f.name)
+	}
+	f.PrintDefaults()
+}
+
+// NOTE: Usage is not just defaultUsage(CommandLine)
+// because it serves (via godoc flag Usage) as the example
+// for how to write your own usage function.
+
+// Usage prints a usage message documenting all defined command-line flags
+// to CommandLine's output, which by default is os.Stderr.
+// It is called when an error occurs while parsing flags.
+// The function is a variable that may be changed to point to a custom function.
+// By default it prints a simple header and calls PrintDefaults; for details about the
+// format of the output and how to control it, see the documentation for PrintDefaults.
+// Custom usage functions may choose to exit the program; by default exiting
+// happens anyway as the command line's error handling strategy is set to
+// ExitOnError.
+var Usage = func() {
+	fmt.Fprintf(CommandLine.Output(), "Usage of %s:\n", os.Args[0])
+	PrintDefaults()
+}
+
+// NFlag returns the number of flags that have been set.
+func (f *FlagSet) NFlag() int { return len(f.actual) }
+
+// NFlag returns the number of command-line flags that have been set.
+func NFlag() int { return len(CommandLine.actual) }
+
+// Arg returns the i'th argument. Arg(0) is the first remaining argument
+// after flags have been processed. Arg returns an empty string if the
+// requested element does not exist.
+func (f *FlagSet) Arg(i int) string {
+	if i < 0 || i >= len(f.args) {
+		return ""
+	}
+	return f.args[i]
+}
+
+// Arg returns the i'th command-line argument. Arg(0) is the first remaining argument
+// after flags have been processed. Arg returns an empty string if the
+// requested element does not exist.
+func Arg(i int) string {
+	return CommandLine.Arg(i)
+}
+
+// NArg is the number of arguments remaining after flags have been processed.
+func (f *FlagSet) NArg() int { return len(f.args) }
+
+// NArg is the number of arguments remaining after flags have been processed.
+func NArg() int { return len(CommandLine.args) }
+
+// Args returns the non-flag arguments.
+func (f *FlagSet) Args() []string { return f.args }
+
+// Args returns the non-flag command-line arguments.
+func Args() []string { return CommandLine.args }
+
+// BoolVar defines a bool flag with specified name, default value, and usage string.
+// The argument p points to a bool variable in which to store the value of the flag.
+func (f *FlagSet) BoolVar(p *bool, name string, value bool, usage string) {
+	f.Var(newBoolValue(value, p), name, usage)
+}
+
+// BoolVar defines a bool flag with specified name, default value, and usage string.
+// The argument p points to a bool variable in which to store the value of the flag.
+func BoolVar(p *bool, name string, value bool, usage string) {
+	CommandLine.Var(newBoolValue(value, p), name, usage)
+}
+
+// Bool defines a bool flag with specified name, default value, and usage string.
+// The return value is the address of a bool variable that stores the value of the flag.
+func (f *FlagSet) Bool(name string, value bool, usage string) *bool {
+	p := new(bool)
+	f.BoolVar(p, name, value, usage)
+	return p
+}
+
+// Bool defines a bool flag with specified name, default value, and usage string.
+// The return value is the address of a bool variable that stores the value of the flag.
+func Bool(name string, value bool, usage string) *bool {
+	return CommandLine.Bool(name, value, usage)
+}
+
+// IntVar defines an int flag with specified name, default value, and usage string.
+// The argument p points to an int variable in which to store the value of the flag.
+func (f *FlagSet) IntVar(p *int, name string, value int, usage string) {
+	f.Var(newIntValue(value, p), name, usage)
+}
+
+// IntVar defines an int flag with specified name, default value, and usage string.
+// The argument p points to an int variable in which to store the value of the flag.
+func IntVar(p *int, name string, value int, usage string) {
+	CommandLine.Var(newIntValue(value, p), name, usage)
+}
+
+// Int defines an int flag with specified name, default value, and usage string.
+// The return value is the address of an int variable that stores the value of the flag.
+func (f *FlagSet) Int(name string, value int, usage string) *int {
+	p := new(int)
+	f.IntVar(p, name, value, usage)
+	return p
+}
+
+// Int defines an int flag with specified name, default value, and usage string.
+// The return value is the address of an int variable that stores the value of the flag.
+func Int(name string, value int, usage string) *int {
+	return CommandLine.Int(name, value, usage)
+}
+
+// Int64Var defines an int64 flag with specified name, default value, and usage string.
+// The argument p points to an int64 variable in which to store the value of the flag.
+func (f *FlagSet) Int64Var(p *int64, name string, value int64, usage string) {
+	f.Var(newInt64Value(value, p), name, usage)
+}
+
+// Int64Var defines an int64 flag with specified name, default value, and usage string.
+// The argument p points to an int64 variable in which to store the value of the flag.
+func Int64Var(p *int64, name string, value int64, usage string) {
+	CommandLine.Var(newInt64Value(value, p), name, usage)
+}
+
+// Int64 defines an int64 flag with specified name, default value, and usage string.
+// The return value is the address of an int64 variable that stores the value of the flag.
+func (f *FlagSet) Int64(name string, value int64, usage string) *int64 {
+	p := new(int64)
+	f.Int64Var(p, name, value, usage)
+	return p
+}
+
+// Int64 defines an int64 flag with specified name, default value, and usage string.
+// The return value is the address of an int64 variable that stores the value of the flag.
+func Int64(name string, value int64, usage string) *int64 {
+	return CommandLine.Int64(name, value, usage)
+}
+
+// UintVar defines a uint flag with specified name, default value, and usage string.
+// The argument p points to a uint variable in which to store the value of the flag.
+func (f *FlagSet) UintVar(p *uint, name string, value uint, usage string) {
+	f.Var(newUintValue(value, p), name, usage)
+}
+
+// UintVar defines a uint flag with specified name, default value, and usage string.
+// The argument p points to a uint variable in which to store the value of the flag.
+func UintVar(p *uint, name string, value uint, usage string) {
+	CommandLine.Var(newUintValue(value, p), name, usage)
+}
+
+// Uint defines a uint flag with specified name, default value, and usage string.
+// The return value is the address of a uint variable that stores the value of the flag.
+func (f *FlagSet) Uint(name string, value uint, usage string) *uint {
+	p := new(uint)
+	f.UintVar(p, name, value, usage)
+	return p
+}
+
+// Uint defines a uint flag with specified name, default value, and usage string.
+// The return value is the address of a uint variable that stores the value of the flag.
+func Uint(name string, value uint, usage string) *uint {
+	return CommandLine.Uint(name, value, usage)
+}
+
+// Uint64Var defines a uint64 flag with specified name, default value, and usage string.
+// The argument p points to a uint64 variable in which to store the value of the flag.
+func (f *FlagSet) Uint64Var(p *uint64, name string, value uint64, usage string) {
+	f.Var(newUint64Value(value, p), name, usage)
+}
+
+// Uint64Var defines a uint64 flag with specified name, default value, and usage string.
+// The argument p points to a uint64 variable in which to store the value of the flag.
+func Uint64Var(p *uint64, name string, value uint64, usage string) {
+	CommandLine.Var(newUint64Value(value, p), name, usage)
+}
+
+// Uint64 defines a uint64 flag with specified name, default value, and usage string.
+// The return value is the address of a uint64 variable that stores the value of the flag.
+func (f *FlagSet) Uint64(name string, value uint64, usage string) *uint64 {
+	p := new(uint64)
+	f.Uint64Var(p, name, value, usage)
+	return p
+}
+
+// Uint64 defines a uint64 flag with specified name, default value, and usage string.
+// The return value is the address of a uint64 variable that stores the value of the flag.
+func Uint64(name string, value uint64, usage string) *uint64 {
+	return CommandLine.Uint64(name, value, usage)
+}
+
+// StringVar defines a string flag with specified name, default value, and usage string.
+// The argument p points to a string variable in which to store the value of the flag.
+func (f *FlagSet) StringVar(p *string, name string, value string, usage string) {
+	f.Var(newStringValue(value, p), name, usage)
+}
+
+// StringVar defines a string flag with specified name, default value, and usage string.
+// The argument p points to a string variable in which to store the value of the flag.
+func StringVar(p *string, name string, value string, usage string) {
+	CommandLine.Var(newStringValue(value, p), name, usage)
+}
+
+// String defines a string flag with specified name, default value, and usage string.
+// The return value is the address of a string variable that stores the value of the flag.
+func (f *FlagSet) String(name string, value string, usage string) *string {
+	p := new(string)
+	f.StringVar(p, name, value, usage)
+	return p
+}
+
+// String defines a string flag with specified name, default value, and usage string.
+// The return value is the address of a string variable that stores the value of the flag.
+func String(name string, value string, usage string) *string {
+	return CommandLine.String(name, value, usage)
+}
+
+// Float64Var defines a float64 flag with specified name, default value, and usage string.
+// The argument p points to a float64 variable in which to store the value of the flag.
+func (f *FlagSet) Float64Var(p *float64, name string, value float64, usage string) {
+	f.Var(newFloat64Value(value, p), name, usage)
+}
+
+// Float64Var defines a float64 flag with specified name, default value, and usage string.
+// The argument p points to a float64 variable in which to store the value of the flag.
+func Float64Var(p *float64, name string, value float64, usage string) {
+	CommandLine.Var(newFloat64Value(value, p), name, usage)
+}
+
+// Float64 defines a float64 flag with specified name, default value, and usage string.
+// The return value is the address of a float64 variable that stores the value of the flag.
+func (f *FlagSet) Float64(name string, value float64, usage string) *float64 {
+	p := new(float64)
+	f.Float64Var(p, name, value, usage)
+	return p
+}
+
+// Float64 defines a float64 flag with specified name, default value, and usage string.
+// The return value is the address of a float64 variable that stores the value of the flag.
+func Float64(name string, value float64, usage string) *float64 {
+	return CommandLine.Float64(name, value, usage)
+}
+
+// DurationVar defines a time.Duration flag with specified name, default value, and usage string.
+// The argument p points to a time.Duration variable in which to store the value of the flag.
+// The flag accepts a value acceptable to time.ParseDuration.
+func (f *FlagSet) DurationVar(p *time.Duration, name string, value time.Duration, usage string) {
+	f.Var(newDurationValue(value, p), name, usage)
+}
+
+// DurationVar defines a time.Duration flag with specified name, default value, and usage string.
+// The argument p points to a time.Duration variable in which to store the value of the flag.
+// The flag accepts a value acceptable to time.ParseDuration.
+func DurationVar(p *time.Duration, name string, value time.Duration, usage string) {
+	CommandLine.Var(newDurationValue(value, p), name, usage)
+}
+
+// Duration defines a time.Duration flag with specified name, default value, and usage string.
+// The return value is the address of a time.Duration variable that stores the value of the flag.
+// The flag accepts a value acceptable to time.ParseDuration.
+func (f *FlagSet) Duration(name string, value time.Duration, usage string) *time.Duration {
+	p := new(time.Duration)
+	f.DurationVar(p, name, value, usage)
+	return p
+}
+
+// Duration defines a time.Duration flag with specified name, default value, and usage string.
+// The return value is the address of a time.Duration variable that stores the value of the flag.
+// The flag accepts a value acceptable to time.ParseDuration.
+func Duration(name string, value time.Duration, usage string) *time.Duration {
+	return CommandLine.Duration(name, value, usage)
+}
+
+// TextVar defines a flag with a specified name, default value, and usage string.
+// The argument p must be a pointer to a variable that will hold the value
+// of the flag, and p must implement encoding.TextUnmarshaler.
+// If the flag is used, the flag value will be passed to p's UnmarshalText method.
+// The type of the default value must be the same as the type of p.
+func (f *FlagSet) TextVar(p encoding.TextUnmarshaler, name string, value encoding.TextMarshaler, usage string) {
+	f.Var(newTextValue(value, p), name, usage)
+}
+
+// TextVar defines a flag with a specified name, default value, and usage string.
+// The argument p must be a pointer to a variable that will hold the value
+// of the flag, and p must implement encoding.TextUnmarshaler.
+// If the flag is used, the flag value will be passed to p's UnmarshalText method.
+// The type of the default value must be the same as the type of p.
+func TextVar(p encoding.TextUnmarshaler, name string, value encoding.TextMarshaler, usage string) {
+	CommandLine.Var(newTextValue(value, p), name, usage)
+}
+
+// Func defines a flag with the specified name and usage string.
+// Each time the flag is seen, fn is called with the value of the flag.
+// If fn returns a non-nil error, it will be treated as a flag value parsing error.
+func (f *FlagSet) Func(name, usage string, fn func(string) error) {
+	f.Var(funcValue(fn), name, usage)
+}
+
+// Func defines a flag with the specified name and usage string.
+// Each time the flag is seen, fn is called with the value of the flag.
+// If fn returns a non-nil error, it will be treated as a flag value parsing error.
+func Func(name, usage string, fn func(string) error) {
+	CommandLine.Func(name, usage, fn)
+}
+
+// Var defines a flag with the specified name and usage string. The type and
+// value of the flag are represented by the first argument, of type Value, which
+// typically holds a user-defined implementation of Value. For instance, the
+// caller could create a flag that turns a comma-separated string into a slice
+// of strings by giving the slice the methods of Value; in particular, Set would
+// decompose the comma-separated string into the slice.
+func (f *FlagSet) Var(value Value, name string, usage string) {
+	// Flag must not begin "-" or contain "=".
+	if strings.HasPrefix(name, "-") {
+		panic(f.sprintf("flag %q begins with -", name))
+	} else if strings.Contains(name, "=") {
+		panic(f.sprintf("flag %q contains =", name))
+	}
+
+	// Remember the default value as a string; it won't change.
+	flag := &Flag{name, usage, value, value.String()}
+	_, alreadythere := f.formal[name]
+	if alreadythere {
+		var msg string
+		if f.name == "" {
+			msg = f.sprintf("flag redefined: %s", name)
+		} else {
+			msg = f.sprintf("%s flag redefined: %s", f.name, name)
+		}
+		panic(msg) // Happens only if flags are declared with identical names
+	}
+	if f.formal == nil {
+		f.formal = make(map[string]*Flag)
+	}
+	f.formal[name] = flag
+}
+
+// Var defines a flag with the specified name and usage string. The type and
+// value of the flag are represented by the first argument, of type Value, which
+// typically holds a user-defined implementation of Value. For instance, the
+// caller could create a flag that turns a comma-separated string into a slice
+// of strings by giving the slice the methods of Value; in particular, Set would
+// decompose the comma-separated string into the slice.
+func Var(value Value, name string, usage string) {
+	CommandLine.Var(value, name, usage)
+}
+
+// sprintf formats the message, prints it to output, and returns it.
+func (f *FlagSet) sprintf(format string, a ...any) string {
+	msg := fmt.Sprintf(format, a...)
+	fmt.Fprintln(f.Output(), msg)
+	return msg
+}
+
+// failf prints to standard error a formatted error and usage message and
+// returns the error.
+func (f *FlagSet) failf(format string, a ...any) error {
+	msg := f.sprintf(format, a...)
+	f.usage()
+	return errors.New(msg)
+}
+
+// usage calls the Usage method for the flag set if one is specified,
+// or the appropriate default usage function otherwise.
+func (f *FlagSet) usage() {
+	if f.Usage == nil {
+		f.defaultUsage()
+	} else {
+		f.Usage()
+	}
+}
+
+// parseOne parses one flag. It reports whether a flag was seen.
+func (f *FlagSet) parseOne() (bool, error) {
+	if len(f.args) == 0 {
+		return false, nil
+	}
+	s := f.args[0]
+	if len(s) < 2 || s[0] != '-' {
+		return false, nil
+	}
+	numMinuses := 1
+	if s[1] == '-' {
+		numMinuses++
+		if len(s) == 2 { // "--" terminates the flags
+			f.args = f.args[1:]
+			return false, nil
+		}
+	}
+	name := s[numMinuses:]
+	if len(name) == 0 || name[0] == '-' || name[0] == '=' {
+		return false, f.failf("bad flag syntax: %s", s)
+	}
+
+	// it's a flag. does it have an argument?
+	f.args = f.args[1:]
+	hasValue := false
+	value := ""
+	for i := 1; i < len(name); i++ { // equals cannot be first
+		if name[i] == '=' {
+			value = name[i+1:]
+			hasValue = true
+			name = name[0:i]
+			break
+		}
+	}
+	m := f.formal
+	flag, alreadythere := m[name] // BUG
+	if !alreadythere {
+		if name == "help" || name == "h" { // special case for nice help message.
+			f.usage()
+			return false, ErrHelp
+		}
+		return false, f.failf("flag provided but not defined: -%s", name)
+	}
+
+	if fv, ok := flag.Value.(boolFlag); ok && fv.IsBoolFlag() { // special case: doesn't need an arg
+		if hasValue {
+			if err := fv.Set(value); err != nil {
+				return false, f.failf("invalid boolean value %q for -%s: %v", value, name, err)
+			}
+		} else {
+			if err := fv.Set("true"); err != nil {
+				return false, f.failf("invalid boolean flag %s: %v", name, err)
+			}
+		}
+	} else {
+		// It must have a value, which might be the next argument.
+		if !hasValue && len(f.args) > 0 {
+			// value is the next arg
+			hasValue = true
+			value, f.args = f.args[0], f.args[1:]
+		}
+		if !hasValue {
+			return false, f.failf("flag needs an argument: -%s", name)
+		}
+		if err := flag.Value.Set(value); err != nil {
+			return false, f.failf("invalid value %q for flag -%s: %v", value, name, err)
+		}
+	}
+	if f.actual == nil {
+		f.actual = make(map[string]*Flag)
+	}
+	f.actual[name] = flag
+	return true, nil
+}
+
+// Parse parses flag definitions from the argument list, which should not
+// include the command name. Must be called after all flags in the FlagSet
+// are defined and before flags are accessed by the program.
+// The return value will be ErrHelp if -help or -h were set but not defined.
+func (f *FlagSet) Parse(arguments []string) error {
+	f.parsed = true
+	f.args = arguments
+	for {
+		seen, err := f.parseOne()
+		if seen {
+			continue
+		}
+		if err == nil {
+			break
+		}
+		switch f.errorHandling {
+		case ContinueOnError:
+			return err
+		case ExitOnError:
+			if err == ErrHelp {
+				os.Exit(0)
+			}
+			os.Exit(2)
+		case PanicOnError:
+			panic(err)
+		}
+	}
+	return nil
+}
+
+// Parsed reports whether f.Parse has been called.
+func (f *FlagSet) Parsed() bool {
+	return f.parsed
+}
+
+// Parse parses the command-line flags from os.Args[1:]. Must be called
+// after all flags are defined and before flags are accessed by the program.
+func Parse() {
+	// Ignore errors; CommandLine is set for ExitOnError.
+	CommandLine.Parse(os.Args[1:])
+}
+
+// Parsed reports whether the command-line flags have been parsed.
+func Parsed() bool {
+	return CommandLine.Parsed()
+}
+
+// CommandLine is the default set of command-line flags, parsed from os.Args.
+// The top-level functions such as BoolVar, Arg, and so on are wrappers for the
+// methods of CommandLine.
+var CommandLine = NewFlagSet(os.Args[0], ExitOnError)
+
+func init() {
+	// Override generic FlagSet default Usage with call to global Usage.
+	// Note: This is not CommandLine.Usage = Usage,
+	// because we want any eventual call to use any updated value of Usage,
+	// not the value it has when this line is run.
+	CommandLine.Usage = commandLineUsage
+}
+
+func commandLineUsage() {
+	Usage()
+}
+
+// NewFlagSet returns a new, empty flag set with the specified name and
+// error handling property. If the name is not empty, it will be printed
+// in the default usage message and in error messages.
+func NewFlagSet(name string, errorHandling ErrorHandling) *FlagSet {
+	f := &FlagSet{
+		name:          name,
+		errorHandling: errorHandling,
+	}
+	f.Usage = f.defaultUsage
+	return f
+}
+
+// Init sets the name and error handling property for a flag set.
+// By default, the zero FlagSet uses an empty name and the
+// ContinueOnError error handling policy.
+func (f *FlagSet) Init(name string, errorHandling ErrorHandling) {
+	f.name = name
+	f.errorHandling = errorHandling
+}
diff --git a/contrib/go/_std_1.19/src/fmt/doc.go b/contrib/go/_std_1.19/src/fmt/doc.go
new file mode 100644
index 0000000000..9785ed9526
--- /dev/null
+++ b/contrib/go/_std_1.19/src/fmt/doc.go
@@ -0,0 +1,383 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package fmt implements formatted I/O with functions analogous
+to C's printf and scanf.  The format 'verbs' are derived from C's but
+are simpler.
+
+# Printing
+
+The verbs:
+
+General:
+
+	%v	the value in a default format
+		when printing structs, the plus flag (%+v) adds field names
+	%#v	a Go-syntax representation of the value
+	%T	a Go-syntax representation of the type of the value
+	%%	a literal percent sign; consumes no value
+
+Boolean:
+
+	%t	the word true or false
+
+Integer:
+
+	%b	base 2
+	%c	the character represented by the corresponding Unicode code point
+	%d	base 10
+	%o	base 8
+	%O	base 8 with 0o prefix
+	%q	a single-quoted character literal safely escaped with Go syntax.
+	%x	base 16, with lower-case letters for a-f
+	%X	base 16, with upper-case letters for A-F
+	%U	Unicode format: U+1234; same as "U+%04X"
+
+Floating-point and complex constituents:
+
+	%b	decimalless scientific notation with exponent a power of two,
+		in the manner of strconv.FormatFloat with the 'b' format,
+		e.g. -123456p-78
+	%e	scientific notation, e.g. -1.234456e+78
+	%E	scientific notation, e.g. -1.234456E+78
+	%f	decimal point but no exponent, e.g. 123.456
+	%F	synonym for %f
+	%g	%e for large exponents, %f otherwise. Precision is discussed below.
+	%G	%E for large exponents, %F otherwise
+	%x	hexadecimal notation (with decimal power of two exponent), e.g. -0x1.23abcp+20
+	%X	upper-case hexadecimal notation, e.g. -0X1.23ABCP+20
+
+String and slice of bytes (treated equivalently with these verbs):
+
+	%s	the uninterpreted bytes of the string or slice
+	%q	a double-quoted string safely escaped with Go syntax
+	%x	base 16, lower-case, two characters per byte
+	%X	base 16, upper-case, two characters per byte
+
+Slice:
+
+	%p	address of 0th element in base 16 notation, with leading 0x
+
+Pointer:
+
+	%p	base 16 notation, with leading 0x
+	The %b, %d, %o, %x and %X verbs also work with pointers,
+	formatting the value exactly as if it were an integer.
+
+The default format for %v is:
+
+	bool:                    %t
+	int, int8 etc.:          %d
+	uint, uint8 etc.:        %d, %#x if printed with %#v
+	float32, complex64, etc: %g
+	string:                  %s
+	chan:                    %p
+	pointer:                 %p
+
+For compound objects, the elements are printed using these rules, recursively,
+laid out like this:
+
+	struct:             {field0 field1 ...}
+	array, slice:       [elem0 elem1 ...]
+	maps:               map[key1:value1 key2:value2 ...]
+	pointer to above:   &{}, &[], &map[]
+
+Width is specified by an optional decimal number immediately preceding the verb.
+If absent, the width is whatever is necessary to represent the value.
+Precision is specified after the (optional) width by a period followed by a
+decimal number. If no period is present, a default precision is used.
+A period with no following number specifies a precision of zero.
+Examples:
+
+	%f     default width, default precision
+	%9f    width 9, default precision
+	%.2f   default width, precision 2
+	%9.2f  width 9, precision 2
+	%9.f   width 9, precision 0
+
+Width and precision are measured in units of Unicode code points,
+that is, runes. (This differs from C's printf where the
+units are always measured in bytes.) Either or both of the flags
+may be replaced with the character '*', causing their values to be
+obtained from the next operand (preceding the one to format),
+which must be of type int.
+
+For most values, width is the minimum number of runes to output,
+padding the formatted form with spaces if necessary.
+
+For strings, byte slices and byte arrays, however, precision
+limits the length of the input to be formatted (not the size of
+the output), truncating if necessary. Normally it is measured in
+runes, but for these types when formatted with the %x or %X format
+it is measured in bytes.
+
+For floating-point values, width sets the minimum width of the field and
+precision sets the number of places after the decimal, if appropriate,
+except that for %g/%G precision sets the maximum number of significant
+digits (trailing zeros are removed). For example, given 12.345 the format
+%6.3f prints 12.345 while %.3g prints 12.3. The default precision for %e, %f
+and %#g is 6; for %g it is the smallest number of digits necessary to identify
+the value uniquely.
+
+For complex numbers, the width and precision apply to the two
+components independently and the result is parenthesized, so %f applied
+to 1.2+3.4i produces (1.200000+3.400000i).
+
+When formatting a single integer code point or a rune string (type []rune)
+with %q, invalid Unicode code points are changed to the Unicode replacement
+character, U+FFFD, as in strconv.QuoteRune.
+
+Other flags:
+
+	'+'	always print a sign for numeric values;
+		guarantee ASCII-only output for %q (%+q)
+	'-'	pad with spaces on the right rather than the left (left-justify the field)
+	'#'	alternate format: add leading 0b for binary (%#b), 0 for octal (%#o),
+		0x or 0X for hex (%#x or %#X); suppress 0x for %p (%#p);
+		for %q, print a raw (backquoted) string if strconv.CanBackquote
+		returns true;
+		always print a decimal point for %e, %E, %f, %F, %g and %G;
+		do not remove trailing zeros for %g and %G;
+		write e.g. U+0078 'x' if the character is printable for %U (%#U).
+	' '	(space) leave a space for elided sign in numbers (% d);
+		put spaces between bytes printing strings or slices in hex (% x, % X)
+	'0'	pad with leading zeros rather than spaces;
+		for numbers, this moves the padding after the sign;
+		ignored for strings, byte slices and byte arrays
+
+Flags are ignored by verbs that do not expect them.
+For example there is no alternate decimal format, so %#d and %d
+behave identically.
+
+For each Printf-like function, there is also a Print function
+that takes no format and is equivalent to saying %v for every
+operand.  Another variant Println inserts blanks between
+operands and appends a newline.
+
+Regardless of the verb, if an operand is an interface value,
+the internal concrete value is used, not the interface itself.
+Thus:
+
+	var i interface{} = 23
+	fmt.Printf("%v\n", i)
+
+will print 23.
+
+Except when printed using the verbs %T and %p, special
+formatting considerations apply for operands that implement
+certain interfaces. In order of application:
+
+1. If the operand is a reflect.Value, the operand is replaced by the
+concrete value that it holds, and printing continues with the next rule.
+
+2. If an operand implements the Formatter interface, it will
+be invoked. In this case the interpretation of verbs and flags is
+controlled by that implementation.
+
+3. If the %v verb is used with the # flag (%#v) and the operand
+implements the GoStringer interface, that will be invoked.
+
+If the format (which is implicitly %v for Println etc.) is valid
+for a string (%s %q %v %x %X), the following two rules apply:
+
+4. If an operand implements the error interface, the Error method
+will be invoked to convert the object to a string, which will then
+be formatted as required by the verb (if any).
+
+5. If an operand implements method String() string, that method
+will be invoked to convert the object to a string, which will then
+be formatted as required by the verb (if any).
+
+For compound operands such as slices and structs, the format
+applies to the elements of each operand, recursively, not to the
+operand as a whole. Thus %q will quote each element of a slice
+of strings, and %6.2f will control formatting for each element
+of a floating-point array.
+
+However, when printing a byte slice with a string-like verb
+(%s %q %x %X), it is treated identically to a string, as a single item.
+
+To avoid recursion in cases such as
+
+	type X string
+	func (x X) String() string { return Sprintf("<%s>", x) }
+
+convert the value before recurring:
+
+	func (x X) String() string { return Sprintf("<%s>", string(x)) }
+
+Infinite recursion can also be triggered by self-referential data
+structures, such as a slice that contains itself as an element, if
+that type has a String method. Such pathologies are rare, however,
+and the package does not protect against them.
+
+When printing a struct, fmt cannot and therefore does not invoke
+formatting methods such as Error or String on unexported fields.
+
+# Explicit argument indexes
+
+In Printf, Sprintf, and Fprintf, the default behavior is for each
+formatting verb to format successive arguments passed in the call.
+However, the notation [n] immediately before the verb indicates that the
+nth one-indexed argument is to be formatted instead. The same notation
+before a '*' for a width or precision selects the argument index holding
+the value. After processing a bracketed expression [n], subsequent verbs
+will use arguments n+1, n+2, etc. unless otherwise directed.
+
+For example,
+
+	fmt.Sprintf("%[2]d %[1]d\n", 11, 22)
+
+will yield "22 11", while
+
+	fmt.Sprintf("%[3]*.[2]*[1]f", 12.0, 2, 6)
+
+equivalent to
+
+	fmt.Sprintf("%6.2f", 12.0)
+
+will yield " 12.00". Because an explicit index affects subsequent verbs,
+this notation can be used to print the same values multiple times
+by resetting the index for the first argument to be repeated:
+
+	fmt.Sprintf("%d %d %#[1]x %#x", 16, 17)
+
+will yield "16 17 0x10 0x11".
+
+# Format errors
+
+If an invalid argument is given for a verb, such as providing
+a string to %d, the generated string will contain a
+description of the problem, as in these examples:
+
+	Wrong type or unknown verb: %!verb(type=value)
+		Printf("%d", "hi"):        %!d(string=hi)
+	Too many arguments: %!(EXTRA type=value)
+		Printf("hi", "guys"):      hi%!(EXTRA string=guys)
+	Too few arguments: %!verb(MISSING)
+		Printf("hi%d"):            hi%!d(MISSING)
+	Non-int for width or precision: %!(BADWIDTH) or %!(BADPREC)
+		Printf("%*s", 4.5, "hi"):  %!(BADWIDTH)hi
+		Printf("%.*s", 4.5, "hi"): %!(BADPREC)hi
+	Invalid or invalid use of argument index: %!(BADINDEX)
+		Printf("%*[2]d", 7):       %!d(BADINDEX)
+		Printf("%.[2]d", 7):       %!d(BADINDEX)
+
+All errors begin with the string "%!" followed sometimes
+by a single character (the verb) and end with a parenthesized
+description.
+
+If an Error or String method triggers a panic when called by a
+print routine, the fmt package reformats the error message
+from the panic, decorating it with an indication that it came
+through the fmt package.  For example, if a String method
+calls panic("bad"), the resulting formatted message will look
+like
+
+	%!s(PANIC=bad)
+
+The %!s just shows the print verb in use when the failure
+occurred. If the panic is caused by a nil receiver to an Error
+or String method, however, the output is the undecorated
+string, "<nil>".
+
+# Scanning
+
+An analogous set of functions scans formatted text to yield
+values.  Scan, Scanf and Scanln read from os.Stdin; Fscan,
+Fscanf and Fscanln read from a specified io.Reader; Sscan,
+Sscanf and Sscanln read from an argument string.
+
+Scan, Fscan, Sscan treat newlines in the input as spaces.
+
+Scanln, Fscanln and Sscanln stop scanning at a newline and
+require that the items be followed by a newline or EOF.
+
+Scanf, Fscanf, and Sscanf parse the arguments according to a
+format string, analogous to that of Printf. In the text that
+follows, 'space' means any Unicode whitespace character
+except newline.
+
+In the format string, a verb introduced by the % character
+consumes and parses input; these verbs are described in more
+detail below. A character other than %, space, or newline in
+the format consumes exactly that input character, which must
+be present. A newline with zero or more spaces before it in
+the format string consumes zero or more spaces in the input
+followed by a single newline or the end of the input. A space
+following a newline in the format string consumes zero or more
+spaces in the input. Otherwise, any run of one or more spaces
+in the format string consumes as many spaces as possible in
+the input. Unless the run of spaces in the format string
+appears adjacent to a newline, the run must consume at least
+one space from the input or find the end of the input.
+
+The handling of spaces and newlines differs from that of C's
+scanf family: in C, newlines are treated as any other space,
+and it is never an error when a run of spaces in the format
+string finds no spaces to consume in the input.
+
+The verbs behave analogously to those of Printf.
+For example, %x will scan an integer as a hexadecimal number,
+and %v will scan the default representation format for the value.
+The Printf verbs %p and %T and the flags # and + are not implemented.
+For floating-point and complex values, all valid formatting verbs
+(%b %e %E %f %F %g %G %x %X and %v) are equivalent and accept
+both decimal and hexadecimal notation (for example: "2.3e+7", "0x4.5p-8")
+and digit-separating underscores (for example: "3.14159_26535_89793").
+
+Input processed by verbs is implicitly space-delimited: the
+implementation of every verb except %c starts by discarding
+leading spaces from the remaining input, and the %s verb
+(and %v reading into a string) stops consuming input at the first
+space or newline character.
+
+The familiar base-setting prefixes 0b (binary), 0o and 0 (octal),
+and 0x (hexadecimal) are accepted when scanning integers
+without a format or with the %v verb, as are digit-separating
+underscores.
+
+Width is interpreted in the input text but there is no
+syntax for scanning with a precision (no %5.2f, just %5f).
+If width is provided, it applies after leading spaces are
+trimmed and specifies the maximum number of runes to read
+to satisfy the verb. For example,
+
+	Sscanf(" 1234567 ", "%5s%d", &s, &i)
+
+will set s to "12345" and i to 67 while
+
+	Sscanf(" 12 34 567 ", "%5s%d", &s, &i)
+
+will set s to "12" and i to 34.
+
+In all the scanning functions, a carriage return followed
+immediately by a newline is treated as a plain newline
+(\r\n means the same as \n).
+
+In all the scanning functions, if an operand implements method
+Scan (that is, it implements the Scanner interface) that
+method will be used to scan the text for that operand.  Also,
+if the number of arguments scanned is less than the number of
+arguments provided, an error is returned.
+
+All arguments to be scanned must be either pointers to basic
+types or implementations of the Scanner interface.
+
+Like Scanf and Fscanf, Sscanf need not consume its entire input.
+There is no way to recover how much of the input string Sscanf used.
+
+Note: Fscan etc. can read one character (rune) past the input
+they return, which means that a loop calling a scan routine
+may skip some of the input.  This is usually a problem only
+when there is no space between input values.  If the reader
+provided to Fscan implements ReadRune, that method will be used
+to read characters.  If the reader also implements UnreadRune,
+that method will be used to save the character and successive
+calls will not lose data.  To attach ReadRune and UnreadRune
+methods to a reader without that capability, use
+bufio.NewReader.
+*/
+package fmt
diff --git a/contrib/go/_std_1.18/src/fmt/errors.go b/contrib/go/_std_1.19/src/fmt/errors.go
index 4f4daf19e1..4f4daf19e1 100644
--- a/contrib/go/_std_1.18/src/fmt/errors.go
+++ b/contrib/go/_std_1.19/src/fmt/errors.go
diff --git a/contrib/go/_std_1.18/src/fmt/format.go b/contrib/go/_std_1.19/src/fmt/format.go
index bd00e5a5e0..bd00e5a5e0 100644
--- a/contrib/go/_std_1.18/src/fmt/format.go
+++ b/contrib/go/_std_1.19/src/fmt/format.go
diff --git a/contrib/go/_std_1.19/src/fmt/print.go b/contrib/go/_std_1.19/src/fmt/print.go
new file mode 100644
index 0000000000..2af7bd0c42
--- /dev/null
+++ b/contrib/go/_std_1.19/src/fmt/print.go
@@ -0,0 +1,1203 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package fmt
+
+import (
+	"internal/fmtsort"
+	"io"
+	"os"
+	"reflect"
+	"sync"
+	"unicode/utf8"
+)
+
+// Strings for use with buffer.WriteString.
+// This is less overhead than using buffer.Write with byte arrays.
+const (
+	commaSpaceString  = ", "
+	nilAngleString    = "<nil>"
+	nilParenString    = "(nil)"
+	nilString         = "nil"
+	mapString         = "map["
+	percentBangString = "%!"
+	missingString     = "(MISSING)"
+	badIndexString    = "(BADINDEX)"
+	panicString       = "(PANIC="
+	extraString       = "%!(EXTRA "
+	badWidthString    = "%!(BADWIDTH)"
+	badPrecString     = "%!(BADPREC)"
+	noVerbString      = "%!(NOVERB)"
+	invReflectString  = "<invalid reflect.Value>"
+)
+
+// State represents the printer state passed to custom formatters.
+// It provides access to the io.Writer interface plus information about
+// the flags and options for the operand's format specifier.
+type State interface {
+	// Write is the function to call to emit formatted output to be printed.
+	Write(b []byte) (n int, err error)
+	// Width returns the value of the width option and whether it has been set.
+	Width() (wid int, ok bool)
+	// Precision returns the value of the precision option and whether it has been set.
+	Precision() (prec int, ok bool)
+
+	// Flag reports whether the flag c, a character, has been set.
+	Flag(c int) bool
+}
+
+// Formatter is implemented by any value that has a Format method.
+// The implementation controls how State and rune are interpreted,
+// and may call Sprint(f) or Fprint(f) etc. to generate its output.
+type Formatter interface {
+	Format(f State, verb rune)
+}
+
+// Stringer is implemented by any value that has a String method,
+// which defines the “native” format for that value.
+// The String method is used to print values passed as an operand
+// to any format that accepts a string or to an unformatted printer
+// such as Print.
+type Stringer interface {
+	String() string
+}
+
+// GoStringer is implemented by any value that has a GoString method,
+// which defines the Go syntax for that value.
+// The GoString method is used to print values passed as an operand
+// to a %#v format.
+type GoStringer interface {
+	GoString() string
+}
+
+// Use simple []byte instead of bytes.Buffer to avoid large dependency.
+type buffer []byte
+
+func (b *buffer) write(p []byte) {
+	*b = append(*b, p...)
+}
+
+func (b *buffer) writeString(s string) {
+	*b = append(*b, s...)
+}
+
+func (b *buffer) writeByte(c byte) {
+	*b = append(*b, c)
+}
+
+func (bp *buffer) writeRune(r rune) {
+	if r < utf8.RuneSelf {
+		*bp = append(*bp, byte(r))
+		return
+	}
+
+	b := *bp
+	n := len(b)
+	for n+utf8.UTFMax > cap(b) {
+		b = append(b, 0)
+	}
+	w := utf8.EncodeRune(b[n:n+utf8.UTFMax], r)
+	*bp = b[:n+w]
+}
+
+// pp is used to store a printer's state and is reused with sync.Pool to avoid allocations.
+type pp struct {
+	buf buffer
+
+	// arg holds the current item, as an interface{}.
+	arg any
+
+	// value is used instead of arg for reflect values.
+	value reflect.Value
+
+	// fmt is used to format basic items such as integers or strings.
+	fmt fmt
+
+	// reordered records whether the format string used argument reordering.
+	reordered bool
+	// goodArgNum records whether the most recent reordering directive was valid.
+	goodArgNum bool
+	// panicking is set by catchPanic to avoid infinite panic, recover, panic, ... recursion.
+	panicking bool
+	// erroring is set when printing an error string to guard against calling handleMethods.
+	erroring bool
+	// wrapErrs is set when the format string may contain a %w verb.
+	wrapErrs bool
+	// wrappedErr records the target of the %w verb.
+	wrappedErr error
+}
+
+var ppFree = sync.Pool{
+	New: func() any { return new(pp) },
+}
+
+// newPrinter allocates a new pp struct or grabs a cached one.
+func newPrinter() *pp {
+	p := ppFree.Get().(*pp)
+	p.panicking = false
+	p.erroring = false
+	p.wrapErrs = false
+	p.fmt.init(&p.buf)
+	return p
+}
+
+// free saves used pp structs in ppFree; avoids an allocation per invocation.
+func (p *pp) free() {
+	// Proper usage of a sync.Pool requires each entry to have approximately
+	// the same memory cost. To obtain this property when the stored type
+	// contains a variably-sized buffer, we add a hard limit on the maximum buffer
+	// to place back in the pool.
+	//
+	// See https://golang.org/issue/23199
+	if cap(p.buf) > 64<<10 {
+		return
+	}
+
+	p.buf = p.buf[:0]
+	p.arg = nil
+	p.value = reflect.Value{}
+	p.wrappedErr = nil
+	ppFree.Put(p)
+}
+
+func (p *pp) Width() (wid int, ok bool) { return p.fmt.wid, p.fmt.widPresent }
+
+func (p *pp) Precision() (prec int, ok bool) { return p.fmt.prec, p.fmt.precPresent }
+
+func (p *pp) Flag(b int) bool {
+	switch b {
+	case '-':
+		return p.fmt.minus
+	case '+':
+		return p.fmt.plus || p.fmt.plusV
+	case '#':
+		return p.fmt.sharp || p.fmt.sharpV
+	case ' ':
+		return p.fmt.space
+	case '0':
+		return p.fmt.zero
+	}
+	return false
+}
+
+// Implement Write so we can call Fprintf on a pp (through State), for
+// recursive use in custom verbs.
+func (p *pp) Write(b []byte) (ret int, err error) {
+	p.buf.write(b)
+	return len(b), nil
+}
+
+// Implement WriteString so that we can call io.WriteString
+// on a pp (through state), for efficiency.
+func (p *pp) WriteString(s string) (ret int, err error) {
+	p.buf.writeString(s)
+	return len(s), nil
+}
+
+// These routines end in 'f' and take a format string.
+
+// Fprintf formats according to a format specifier and writes to w.
+// It returns the number of bytes written and any write error encountered.
+func Fprintf(w io.Writer, format string, a ...any) (n int, err error) {
+	p := newPrinter()
+	p.doPrintf(format, a)
+	n, err = w.Write(p.buf)
+	p.free()
+	return
+}
+
+// Printf formats according to a format specifier and writes to standard output.
+// It returns the number of bytes written and any write error encountered.
+func Printf(format string, a ...any) (n int, err error) {
+	return Fprintf(os.Stdout, format, a...)
+}
+
+// Sprintf formats according to a format specifier and returns the resulting string.
+func Sprintf(format string, a ...any) string {
+	p := newPrinter()
+	p.doPrintf(format, a)
+	s := string(p.buf)
+	p.free()
+	return s
+}
+
+// Appendf formats according to a format specifier, appends the result to the byte
+// slice, and returns the updated slice.
+func Appendf(b []byte, format string, a ...any) []byte {
+	p := newPrinter()
+	p.doPrintf(format, a)
+	b = append(b, p.buf...)
+	p.free()
+	return b
+}
+
+// These routines do not take a format string
+
+// Fprint formats using the default formats for its operands and writes to w.
+// Spaces are added between operands when neither is a string.
+// It returns the number of bytes written and any write error encountered.
+func Fprint(w io.Writer, a ...any) (n int, err error) {
+	p := newPrinter()
+	p.doPrint(a)
+	n, err = w.Write(p.buf)
+	p.free()
+	return
+}
+
+// Print formats using the default formats for its operands and writes to standard output.
+// Spaces are added between operands when neither is a string.
+// It returns the number of bytes written and any write error encountered.
+func Print(a ...any) (n int, err error) {
+	return Fprint(os.Stdout, a...)
+}
+
+// Sprint formats using the default formats for its operands and returns the resulting string.
+// Spaces are added between operands when neither is a string.
+func Sprint(a ...any) string {
+	p := newPrinter()
+	p.doPrint(a)
+	s := string(p.buf)
+	p.free()
+	return s
+}
+
+// Append formats using the default formats for its operands, appends the result to
+// the byte slice, and returns the updated slice.
+func Append(b []byte, a ...any) []byte {
+	p := newPrinter()
+	p.doPrint(a)
+	b = append(b, p.buf...)
+	p.free()
+	return b
+}
+
+// These routines end in 'ln', do not take a format string,
+// always add spaces between operands, and add a newline
+// after the last operand.
+
+// Fprintln formats using the default formats for its operands and writes to w.
+// Spaces are always added between operands and a newline is appended.
+// It returns the number of bytes written and any write error encountered.
+func Fprintln(w io.Writer, a ...any) (n int, err error) {
+	p := newPrinter()
+	p.doPrintln(a)
+	n, err = w.Write(p.buf)
+	p.free()
+	return
+}
+
+// Println formats using the default formats for its operands and writes to standard output.
+// Spaces are always added between operands and a newline is appended.
+// It returns the number of bytes written and any write error encountered.
+func Println(a ...any) (n int, err error) {
+	return Fprintln(os.Stdout, a...)
+}
+
+// Sprintln formats using the default formats for its operands and returns the resulting string.
+// Spaces are always added between operands and a newline is appended.
+func Sprintln(a ...any) string {
+	p := newPrinter()
+	p.doPrintln(a)
+	s := string(p.buf)
+	p.free()
+	return s
+}
+
+// Appendln formats using the default formats for its operands, appends the result
+// to the byte slice, and returns the updated slice. Spaces are always added
+// between operands and a newline is appended.
+func Appendln(b []byte, a ...any) []byte {
+	p := newPrinter()
+	p.doPrintln(a)
+	b = append(b, p.buf...)
+	p.free()
+	return b
+}
+
+// getField gets the i'th field of the struct value.
+// If the field is itself is an interface, return a value for
+// the thing inside the interface, not the interface itself.
+func getField(v reflect.Value, i int) reflect.Value {
+	val := v.Field(i)
+	if val.Kind() == reflect.Interface && !val.IsNil() {
+		val = val.Elem()
+	}
+	return val
+}
+
+// tooLarge reports whether the magnitude of the integer is
+// too large to be used as a formatting width or precision.
+func tooLarge(x int) bool {
+	const max int = 1e6
+	return x > max || x < -max
+}
+
+// parsenum converts ASCII to integer.  num is 0 (and isnum is false) if no number present.
+func parsenum(s string, start, end int) (num int, isnum bool, newi int) {
+	if start >= end {
+		return 0, false, end
+	}
+	for newi = start; newi < end && '0' <= s[newi] && s[newi] <= '9'; newi++ {
+		if tooLarge(num) {
+			return 0, false, end // Overflow; crazy long number most likely.
+		}
+		num = num*10 + int(s[newi]-'0')
+		isnum = true
+	}
+	return
+}
+
+func (p *pp) unknownType(v reflect.Value) {
+	if !v.IsValid() {
+		p.buf.writeString(nilAngleString)
+		return
+	}
+	p.buf.writeByte('?')
+	p.buf.writeString(v.Type().String())
+	p.buf.writeByte('?')
+}
+
+func (p *pp) badVerb(verb rune) {
+	p.erroring = true
+	p.buf.writeString(percentBangString)
+	p.buf.writeRune(verb)
+	p.buf.writeByte('(')
+	switch {
+	case p.arg != nil:
+		p.buf.writeString(reflect.TypeOf(p.arg).String())
+		p.buf.writeByte('=')
+		p.printArg(p.arg, 'v')
+	case p.value.IsValid():
+		p.buf.writeString(p.value.Type().String())
+		p.buf.writeByte('=')
+		p.printValue(p.value, 'v', 0)
+	default:
+		p.buf.writeString(nilAngleString)
+	}
+	p.buf.writeByte(')')
+	p.erroring = false
+}
+
+func (p *pp) fmtBool(v bool, verb rune) {
+	switch verb {
+	case 't', 'v':
+		p.fmt.fmtBoolean(v)
+	default:
+		p.badVerb(verb)
+	}
+}
+
+// fmt0x64 formats a uint64 in hexadecimal and prefixes it with 0x or
+// not, as requested, by temporarily setting the sharp flag.
+func (p *pp) fmt0x64(v uint64, leading0x bool) {
+	sharp := p.fmt.sharp
+	p.fmt.sharp = leading0x
+	p.fmt.fmtInteger(v, 16, unsigned, 'v', ldigits)
+	p.fmt.sharp = sharp
+}
+
+// fmtInteger formats a signed or unsigned integer.
+func (p *pp) fmtInteger(v uint64, isSigned bool, verb rune) {
+	switch verb {
+	case 'v':
+		if p.fmt.sharpV && !isSigned {
+			p.fmt0x64(v, true)
+		} else {
+			p.fmt.fmtInteger(v, 10, isSigned, verb, ldigits)
+		}
+	case 'd':
+		p.fmt.fmtInteger(v, 10, isSigned, verb, ldigits)
+	case 'b':
+		p.fmt.fmtInteger(v, 2, isSigned, verb, ldigits)
+	case 'o', 'O':
+		p.fmt.fmtInteger(v, 8, isSigned, verb, ldigits)
+	case 'x':
+		p.fmt.fmtInteger(v, 16, isSigned, verb, ldigits)
+	case 'X':
+		p.fmt.fmtInteger(v, 16, isSigned, verb, udigits)
+	case 'c':
+		p.fmt.fmtC(v)
+	case 'q':
+		p.fmt.fmtQc(v)
+	case 'U':
+		p.fmt.fmtUnicode(v)
+	default:
+		p.badVerb(verb)
+	}
+}
+
+// fmtFloat formats a float. The default precision for each verb
+// is specified as last argument in the call to fmt_float.
+func (p *pp) fmtFloat(v float64, size int, verb rune) {
+	switch verb {
+	case 'v':
+		p.fmt.fmtFloat(v, size, 'g', -1)
+	case 'b', 'g', 'G', 'x', 'X':
+		p.fmt.fmtFloat(v, size, verb, -1)
+	case 'f', 'e', 'E':
+		p.fmt.fmtFloat(v, size, verb, 6)
+	case 'F':
+		p.fmt.fmtFloat(v, size, 'f', 6)
+	default:
+		p.badVerb(verb)
+	}
+}
+
+// fmtComplex formats a complex number v with
+// r = real(v) and j = imag(v) as (r+ji) using
+// fmtFloat for r and j formatting.
+func (p *pp) fmtComplex(v complex128, size int, verb rune) {
+	// Make sure any unsupported verbs are found before the
+	// calls to fmtFloat to not generate an incorrect error string.
+	switch verb {
+	case 'v', 'b', 'g', 'G', 'x', 'X', 'f', 'F', 'e', 'E':
+		oldPlus := p.fmt.plus
+		p.buf.writeByte('(')
+		p.fmtFloat(real(v), size/2, verb)
+		// Imaginary part always has a sign.
+		p.fmt.plus = true
+		p.fmtFloat(imag(v), size/2, verb)
+		p.buf.writeString("i)")
+		p.fmt.plus = oldPlus
+	default:
+		p.badVerb(verb)
+	}
+}
+
+func (p *pp) fmtString(v string, verb rune) {
+	switch verb {
+	case 'v':
+		if p.fmt.sharpV {
+			p.fmt.fmtQ(v)
+		} else {
+			p.fmt.fmtS(v)
+		}
+	case 's':
+		p.fmt.fmtS(v)
+	case 'x':
+		p.fmt.fmtSx(v, ldigits)
+	case 'X':
+		p.fmt.fmtSx(v, udigits)
+	case 'q':
+		p.fmt.fmtQ(v)
+	default:
+		p.badVerb(verb)
+	}
+}
+
+func (p *pp) fmtBytes(v []byte, verb rune, typeString string) {
+	switch verb {
+	case 'v', 'd':
+		if p.fmt.sharpV {
+			p.buf.writeString(typeString)
+			if v == nil {
+				p.buf.writeString(nilParenString)
+				return
+			}
+			p.buf.writeByte('{')
+			for i, c := range v {
+				if i > 0 {
+					p.buf.writeString(commaSpaceString)
+				}
+				p.fmt0x64(uint64(c), true)
+			}
+			p.buf.writeByte('}')
+		} else {
+			p.buf.writeByte('[')
+			for i, c := range v {
+				if i > 0 {
+					p.buf.writeByte(' ')
+				}
+				p.fmt.fmtInteger(uint64(c), 10, unsigned, verb, ldigits)
+			}
+			p.buf.writeByte(']')
+		}
+	case 's':
+		p.fmt.fmtBs(v)
+	case 'x':
+		p.fmt.fmtBx(v, ldigits)
+	case 'X':
+		p.fmt.fmtBx(v, udigits)
+	case 'q':
+		p.fmt.fmtQ(string(v))
+	default:
+		p.printValue(reflect.ValueOf(v), verb, 0)
+	}
+}
+
+func (p *pp) fmtPointer(value reflect.Value, verb rune) {
+	var u uintptr
+	switch value.Kind() {
+	case reflect.Chan, reflect.Func, reflect.Map, reflect.Pointer, reflect.Slice, reflect.UnsafePointer:
+		u = value.Pointer()
+	default:
+		p.badVerb(verb)
+		return
+	}
+
+	switch verb {
+	case 'v':
+		if p.fmt.sharpV {
+			p.buf.writeByte('(')
+			p.buf.writeString(value.Type().String())
+			p.buf.writeString(")(")
+			if u == 0 {
+				p.buf.writeString(nilString)
+			} else {
+				p.fmt0x64(uint64(u), true)
+			}
+			p.buf.writeByte(')')
+		} else {
+			if u == 0 {
+				p.fmt.padString(nilAngleString)
+			} else {
+				p.fmt0x64(uint64(u), !p.fmt.sharp)
+			}
+		}
+	case 'p':
+		p.fmt0x64(uint64(u), !p.fmt.sharp)
+	case 'b', 'o', 'd', 'x', 'X':
+		p.fmtInteger(uint64(u), unsigned, verb)
+	default:
+		p.badVerb(verb)
+	}
+}
+
+func (p *pp) catchPanic(arg any, verb rune, method string) {
+	if err := recover(); err != nil {
+		// If it's a nil pointer, just say "<nil>". The likeliest causes are a
+		// Stringer that fails to guard against nil or a nil pointer for a
+		// value receiver, and in either case, "<nil>" is a nice result.
+		if v := reflect.ValueOf(arg); v.Kind() == reflect.Pointer && v.IsNil() {
+			p.buf.writeString(nilAngleString)
+			return
+		}
+		// Otherwise print a concise panic message. Most of the time the panic
+		// value will print itself nicely.
+		if p.panicking {
+			// Nested panics; the recursion in printArg cannot succeed.
+			panic(err)
+		}
+
+		oldFlags := p.fmt.fmtFlags
+		// For this output we want default behavior.
+		p.fmt.clearflags()
+
+		p.buf.writeString(percentBangString)
+		p.buf.writeRune(verb)
+		p.buf.writeString(panicString)
+		p.buf.writeString(method)
+		p.buf.writeString(" method: ")
+		p.panicking = true
+		p.printArg(err, 'v')
+		p.panicking = false
+		p.buf.writeByte(')')
+
+		p.fmt.fmtFlags = oldFlags
+	}
+}
+
+func (p *pp) handleMethods(verb rune) (handled bool) {
+	if p.erroring {
+		return
+	}
+	if verb == 'w' {
+		// It is invalid to use %w other than with Errorf, more than once,
+		// or with a non-error arg.
+		err, ok := p.arg.(error)
+		if !ok || !p.wrapErrs || p.wrappedErr != nil {
+			p.wrappedErr = nil
+			p.wrapErrs = false
+			p.badVerb(verb)
+			return true
+		}
+		p.wrappedErr = err
+		// If the arg is a Formatter, pass 'v' as the verb to it.
+		verb = 'v'
+	}
+
+	// Is it a Formatter?
+	if formatter, ok := p.arg.(Formatter); ok {
+		handled = true
+		defer p.catchPanic(p.arg, verb, "Format")
+		formatter.Format(p, verb)
+		return
+	}
+
+	// If we're doing Go syntax and the argument knows how to supply it, take care of it now.
+	if p.fmt.sharpV {
+		if stringer, ok := p.arg.(GoStringer); ok {
+			handled = true
+			defer p.catchPanic(p.arg, verb, "GoString")
+			// Print the result of GoString unadorned.
+			p.fmt.fmtS(stringer.GoString())
+			return
+		}
+	} else {
+		// If a string is acceptable according to the format, see if
+		// the value satisfies one of the string-valued interfaces.
+		// Println etc. set verb to %v, which is "stringable".
+		switch verb {
+		case 'v', 's', 'x', 'X', 'q':
+			// Is it an error or Stringer?
+			// The duplication in the bodies is necessary:
+			// setting handled and deferring catchPanic
+			// must happen before calling the method.
+			switch v := p.arg.(type) {
+			case error:
+				handled = true
+				defer p.catchPanic(p.arg, verb, "Error")
+				p.fmtString(v.Error(), verb)
+				return
+
+			case Stringer:
+				handled = true
+				defer p.catchPanic(p.arg, verb, "String")
+				p.fmtString(v.String(), verb)
+				return
+			}
+		}
+	}
+	return false
+}
+
+func (p *pp) printArg(arg any, verb rune) {
+	p.arg = arg
+	p.value = reflect.Value{}
+
+	if arg == nil {
+		switch verb {
+		case 'T', 'v':
+			p.fmt.padString(nilAngleString)
+		default:
+			p.badVerb(verb)
+		}
+		return
+	}
+
+	// Special processing considerations.
+	// %T (the value's type) and %p (its address) are special; we always do them first.
+	switch verb {
+	case 'T':
+		p.fmt.fmtS(reflect.TypeOf(arg).String())
+		return
+	case 'p':
+		p.fmtPointer(reflect.ValueOf(arg), 'p')
+		return
+	}
+
+	// Some types can be done without reflection.
+	switch f := arg.(type) {
+	case bool:
+		p.fmtBool(f, verb)
+	case float32:
+		p.fmtFloat(float64(f), 32, verb)
+	case float64:
+		p.fmtFloat(f, 64, verb)
+	case complex64:
+		p.fmtComplex(complex128(f), 64, verb)
+	case complex128:
+		p.fmtComplex(f, 128, verb)
+	case int:
+		p.fmtInteger(uint64(f), signed, verb)
+	case int8:
+		p.fmtInteger(uint64(f), signed, verb)
+	case int16:
+		p.fmtInteger(uint64(f), signed, verb)
+	case int32:
+		p.fmtInteger(uint64(f), signed, verb)
+	case int64:
+		p.fmtInteger(uint64(f), signed, verb)
+	case uint:
+		p.fmtInteger(uint64(f), unsigned, verb)
+	case uint8:
+		p.fmtInteger(uint64(f), unsigned, verb)
+	case uint16:
+		p.fmtInteger(uint64(f), unsigned, verb)
+	case uint32:
+		p.fmtInteger(uint64(f), unsigned, verb)
+	case uint64:
+		p.fmtInteger(f, unsigned, verb)
+	case uintptr:
+		p.fmtInteger(uint64(f), unsigned, verb)
+	case string:
+		p.fmtString(f, verb)
+	case []byte:
+		p.fmtBytes(f, verb, "[]byte")
+	case reflect.Value:
+		// Handle extractable values with special methods
+		// since printValue does not handle them at depth 0.
+		if f.IsValid() && f.CanInterface() {
+			p.arg = f.Interface()
+			if p.handleMethods(verb) {
+				return
+			}
+		}
+		p.printValue(f, verb, 0)
+	default:
+		// If the type is not simple, it might have methods.
+		if !p.handleMethods(verb) {
+			// Need to use reflection, since the type had no
+			// interface methods that could be used for formatting.
+			p.printValue(reflect.ValueOf(f), verb, 0)
+		}
+	}
+}
+
+// printValue is similar to printArg but starts with a reflect value, not an interface{} value.
+// It does not handle 'p' and 'T' verbs because these should have been already handled by printArg.
+func (p *pp) printValue(value reflect.Value, verb rune, depth int) {
+	// Handle values with special methods if not already handled by printArg (depth == 0).
+	if depth > 0 && value.IsValid() && value.CanInterface() {
+		p.arg = value.Interface()
+		if p.handleMethods(verb) {
+			return
+		}
+	}
+	p.arg = nil
+	p.value = value
+
+	switch f := value; value.Kind() {
+	case reflect.Invalid:
+		if depth == 0 {
+			p.buf.writeString(invReflectString)
+		} else {
+			switch verb {
+			case 'v':
+				p.buf.writeString(nilAngleString)
+			default:
+				p.badVerb(verb)
+			}
+		}
+	case reflect.Bool:
+		p.fmtBool(f.Bool(), verb)
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		p.fmtInteger(uint64(f.Int()), signed, verb)
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		p.fmtInteger(f.Uint(), unsigned, verb)
+	case reflect.Float32:
+		p.fmtFloat(f.Float(), 32, verb)
+	case reflect.Float64:
+		p.fmtFloat(f.Float(), 64, verb)
+	case reflect.Complex64:
+		p.fmtComplex(f.Complex(), 64, verb)
+	case reflect.Complex128:
+		p.fmtComplex(f.Complex(), 128, verb)
+	case reflect.String:
+		p.fmtString(f.String(), verb)
+	case reflect.Map:
+		if p.fmt.sharpV {
+			p.buf.writeString(f.Type().String())
+			if f.IsNil() {
+				p.buf.writeString(nilParenString)
+				return
+			}
+			p.buf.writeByte('{')
+		} else {
+			p.buf.writeString(mapString)
+		}
+		sorted := fmtsort.Sort(f)
+		for i, key := range sorted.Key {
+			if i > 0 {
+				if p.fmt.sharpV {
+					p.buf.writeString(commaSpaceString)
+				} else {
+					p.buf.writeByte(' ')
+				}
+			}
+			p.printValue(key, verb, depth+1)
+			p.buf.writeByte(':')
+			p.printValue(sorted.Value[i], verb, depth+1)
+		}
+		if p.fmt.sharpV {
+			p.buf.writeByte('}')
+		} else {
+			p.buf.writeByte(']')
+		}
+	case reflect.Struct:
+		if p.fmt.sharpV {
+			p.buf.writeString(f.Type().String())
+		}
+		p.buf.writeByte('{')
+		for i := 0; i < f.NumField(); i++ {
+			if i > 0 {
+				if p.fmt.sharpV {
+					p.buf.writeString(commaSpaceString)
+				} else {
+					p.buf.writeByte(' ')
+				}
+			}
+			if p.fmt.plusV || p.fmt.sharpV {
+				if name := f.Type().Field(i).Name; name != "" {
+					p.buf.writeString(name)
+					p.buf.writeByte(':')
+				}
+			}
+			p.printValue(getField(f, i), verb, depth+1)
+		}
+		p.buf.writeByte('}')
+	case reflect.Interface:
+		value := f.Elem()
+		if !value.IsValid() {
+			if p.fmt.sharpV {
+				p.buf.writeString(f.Type().String())
+				p.buf.writeString(nilParenString)
+			} else {
+				p.buf.writeString(nilAngleString)
+			}
+		} else {
+			p.printValue(value, verb, depth+1)
+		}
+	case reflect.Array, reflect.Slice:
+		switch verb {
+		case 's', 'q', 'x', 'X':
+			// Handle byte and uint8 slices and arrays special for the above verbs.
+			t := f.Type()
+			if t.Elem().Kind() == reflect.Uint8 {
+				var bytes []byte
+				if f.Kind() == reflect.Slice {
+					bytes = f.Bytes()
+				} else if f.CanAddr() {
+					bytes = f.Slice(0, f.Len()).Bytes()
+				} else {
+					// We have an array, but we cannot Slice() a non-addressable array,
+					// so we build a slice by hand. This is a rare case but it would be nice
+					// if reflection could help a little more.
+					bytes = make([]byte, f.Len())
+					for i := range bytes {
+						bytes[i] = byte(f.Index(i).Uint())
+					}
+				}
+				p.fmtBytes(bytes, verb, t.String())
+				return
+			}
+		}
+		if p.fmt.sharpV {
+			p.buf.writeString(f.Type().String())
+			if f.Kind() == reflect.Slice && f.IsNil() {
+				p.buf.writeString(nilParenString)
+				return
+			}
+			p.buf.writeByte('{')
+			for i := 0; i < f.Len(); i++ {
+				if i > 0 {
+					p.buf.writeString(commaSpaceString)
+				}
+				p.printValue(f.Index(i), verb, depth+1)
+			}
+			p.buf.writeByte('}')
+		} else {
+			p.buf.writeByte('[')
+			for i := 0; i < f.Len(); i++ {
+				if i > 0 {
+					p.buf.writeByte(' ')
+				}
+				p.printValue(f.Index(i), verb, depth+1)
+			}
+			p.buf.writeByte(']')
+		}
+	case reflect.Pointer:
+		// pointer to array or slice or struct? ok at top level
+		// but not embedded (avoid loops)
+		if depth == 0 && f.Pointer() != 0 {
+			switch a := f.Elem(); a.Kind() {
+			case reflect.Array, reflect.Slice, reflect.Struct, reflect.Map:
+				p.buf.writeByte('&')
+				p.printValue(a, verb, depth+1)
+				return
+			}
+		}
+		fallthrough
+	case reflect.Chan, reflect.Func, reflect.UnsafePointer:
+		p.fmtPointer(f, verb)
+	default:
+		p.unknownType(f)
+	}
+}
+
+// intFromArg gets the argNumth element of a. On return, isInt reports whether the argument has integer type.
+func intFromArg(a []any, argNum int) (num int, isInt bool, newArgNum int) {
+	newArgNum = argNum
+	if argNum < len(a) {
+		num, isInt = a[argNum].(int) // Almost always OK.
+		if !isInt {
+			// Work harder.
+			switch v := reflect.ValueOf(a[argNum]); v.Kind() {
+			case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+				n := v.Int()
+				if int64(int(n)) == n {
+					num = int(n)
+					isInt = true
+				}
+			case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+				n := v.Uint()
+				if int64(n) >= 0 && uint64(int(n)) == n {
+					num = int(n)
+					isInt = true
+				}
+			default:
+				// Already 0, false.
+			}
+		}
+		newArgNum = argNum + 1
+		if tooLarge(num) {
+			num = 0
+			isInt = false
+		}
+	}
+	return
+}
+
+// parseArgNumber returns the value of the bracketed number, minus 1
+// (explicit argument numbers are one-indexed but we want zero-indexed).
+// The opening bracket is known to be present at format[0].
+// The returned values are the index, the number of bytes to consume
+// up to the closing paren, if present, and whether the number parsed
+// ok. The bytes to consume will be 1 if no closing paren is present.
+func parseArgNumber(format string) (index int, wid int, ok bool) {
+	// There must be at least 3 bytes: [n].
+	if len(format) < 3 {
+		return 0, 1, false
+	}
+
+	// Find closing bracket.
+	for i := 1; i < len(format); i++ {
+		if format[i] == ']' {
+			width, ok, newi := parsenum(format, 1, i)
+			if !ok || newi != i {
+				return 0, i + 1, false
+			}
+			return width - 1, i + 1, true // arg numbers are one-indexed and skip paren.
+		}
+	}
+	return 0, 1, false
+}
+
+// argNumber returns the next argument to evaluate, which is either the value of the passed-in
+// argNum or the value of the bracketed integer that begins format[i:]. It also returns
+// the new value of i, that is, the index of the next byte of the format to process.
+func (p *pp) argNumber(argNum int, format string, i int, numArgs int) (newArgNum, newi int, found bool) {
+	if len(format) <= i || format[i] != '[' {
+		return argNum, i, false
+	}
+	p.reordered = true
+	index, wid, ok := parseArgNumber(format[i:])
+	if ok && 0 <= index && index < numArgs {
+		return index, i + wid, true
+	}
+	p.goodArgNum = false
+	return argNum, i + wid, ok
+}
+
+func (p *pp) badArgNum(verb rune) {
+	p.buf.writeString(percentBangString)
+	p.buf.writeRune(verb)
+	p.buf.writeString(badIndexString)
+}
+
+func (p *pp) missingArg(verb rune) {
+	p.buf.writeString(percentBangString)
+	p.buf.writeRune(verb)
+	p.buf.writeString(missingString)
+}
+
+func (p *pp) doPrintf(format string, a []any) {
+	end := len(format)
+	argNum := 0         // we process one argument per non-trivial format
+	afterIndex := false // previous item in format was an index like [3].
+	p.reordered = false
+formatLoop:
+	for i := 0; i < end; {
+		p.goodArgNum = true
+		lasti := i
+		for i < end && format[i] != '%' {
+			i++
+		}
+		if i > lasti {
+			p.buf.writeString(format[lasti:i])
+		}
+		if i >= end {
+			// done processing format string
+			break
+		}
+
+		// Process one verb
+		i++
+
+		// Do we have flags?
+		p.fmt.clearflags()
+	simpleFormat:
+		for ; i < end; i++ {
+			c := format[i]
+			switch c {
+			case '#':
+				p.fmt.sharp = true
+			case '0':
+				p.fmt.zero = !p.fmt.minus // Only allow zero padding to the left.
+			case '+':
+				p.fmt.plus = true
+			case '-':
+				p.fmt.minus = true
+				p.fmt.zero = false // Do not pad with zeros to the right.
+			case ' ':
+				p.fmt.space = true
+			default:
+				// Fast path for common case of ascii lower case simple verbs
+				// without precision or width or argument indices.
+				if 'a' <= c && c <= 'z' && argNum < len(a) {
+					if c == 'v' {
+						// Go syntax
+						p.fmt.sharpV = p.fmt.sharp
+						p.fmt.sharp = false
+						// Struct-field syntax
+						p.fmt.plusV = p.fmt.plus
+						p.fmt.plus = false
+					}
+					p.printArg(a[argNum], rune(c))
+					argNum++
+					i++
+					continue formatLoop
+				}
+				// Format is more complex than simple flags and a verb or is malformed.
+				break simpleFormat
+			}
+		}
+
+		// Do we have an explicit argument index?
+		argNum, i, afterIndex = p.argNumber(argNum, format, i, len(a))
+
+		// Do we have width?
+		if i < end && format[i] == '*' {
+			i++
+			p.fmt.wid, p.fmt.widPresent, argNum = intFromArg(a, argNum)
+
+			if !p.fmt.widPresent {
+				p.buf.writeString(badWidthString)
+			}
+
+			// We have a negative width, so take its value and ensure
+			// that the minus flag is set
+			if p.fmt.wid < 0 {
+				p.fmt.wid = -p.fmt.wid
+				p.fmt.minus = true
+				p.fmt.zero = false // Do not pad with zeros to the right.
+			}
+			afterIndex = false
+		} else {
+			p.fmt.wid, p.fmt.widPresent, i = parsenum(format, i, end)
+			if afterIndex && p.fmt.widPresent { // "%[3]2d"
+				p.goodArgNum = false
+			}
+		}
+
+		// Do we have precision?
+		if i+1 < end && format[i] == '.' {
+			i++
+			if afterIndex { // "%[3].2d"
+				p.goodArgNum = false
+			}
+			argNum, i, afterIndex = p.argNumber(argNum, format, i, len(a))
+			if i < end && format[i] == '*' {
+				i++
+				p.fmt.prec, p.fmt.precPresent, argNum = intFromArg(a, argNum)
+				// Negative precision arguments don't make sense
+				if p.fmt.prec < 0 {
+					p.fmt.prec = 0
+					p.fmt.precPresent = false
+				}
+				if !p.fmt.precPresent {
+					p.buf.writeString(badPrecString)
+				}
+				afterIndex = false
+			} else {
+				p.fmt.prec, p.fmt.precPresent, i = parsenum(format, i, end)
+				if !p.fmt.precPresent {
+					p.fmt.prec = 0
+					p.fmt.precPresent = true
+				}
+			}
+		}
+
+		if !afterIndex {
+			argNum, i, afterIndex = p.argNumber(argNum, format, i, len(a))
+		}
+
+		if i >= end {
+			p.buf.writeString(noVerbString)
+			break
+		}
+
+		verb, size := rune(format[i]), 1
+		if verb >= utf8.RuneSelf {
+			verb, size = utf8.DecodeRuneInString(format[i:])
+		}
+		i += size
+
+		switch {
+		case verb == '%': // Percent does not absorb operands and ignores f.wid and f.prec.
+			p.buf.writeByte('%')
+		case !p.goodArgNum:
+			p.badArgNum(verb)
+		case argNum >= len(a): // No argument left over to print for the current verb.
+			p.missingArg(verb)
+		case verb == 'v':
+			// Go syntax
+			p.fmt.sharpV = p.fmt.sharp
+			p.fmt.sharp = false
+			// Struct-field syntax
+			p.fmt.plusV = p.fmt.plus
+			p.fmt.plus = false
+			fallthrough
+		default:
+			p.printArg(a[argNum], verb)
+			argNum++
+		}
+	}
+
+	// Check for extra arguments unless the call accessed the arguments
+	// out of order, in which case it's too expensive to detect if they've all
+	// been used and arguably OK if they're not.
+	if !p.reordered && argNum < len(a) {
+		p.fmt.clearflags()
+		p.buf.writeString(extraString)
+		for i, arg := range a[argNum:] {
+			if i > 0 {
+				p.buf.writeString(commaSpaceString)
+			}
+			if arg == nil {
+				p.buf.writeString(nilAngleString)
+			} else {
+				p.buf.writeString(reflect.TypeOf(arg).String())
+				p.buf.writeByte('=')
+				p.printArg(arg, 'v')
+			}
+		}
+		p.buf.writeByte(')')
+	}
+}
+
+func (p *pp) doPrint(a []any) {
+	prevString := false
+	for argNum, arg := range a {
+		isString := arg != nil && reflect.TypeOf(arg).Kind() == reflect.String
+		// Add a space between two non-string arguments.
+		if argNum > 0 && !isString && !prevString {
+			p.buf.writeByte(' ')
+		}
+		p.printArg(arg, 'v')
+		prevString = isString
+	}
+}
+
+// doPrintln is like doPrint but always adds a space between arguments
+// and a newline after the last argument.
+func (p *pp) doPrintln(a []any) {
+	for argNum, arg := range a {
+		if argNum > 0 {
+			p.buf.writeByte(' ')
+		}
+		p.printArg(arg, 'v')
+	}
+	p.buf.writeByte('\n')
+}
diff --git a/contrib/go/_std_1.18/src/fmt/scan.go b/contrib/go/_std_1.19/src/fmt/scan.go
index d38610df35..d38610df35 100644
--- a/contrib/go/_std_1.18/src/fmt/scan.go
+++ b/contrib/go/_std_1.19/src/fmt/scan.go
diff --git a/contrib/go/_std_1.18/src/hash/crc32/crc32.go b/contrib/go/_std_1.19/src/hash/crc32/crc32.go
index f330fdb77a..f330fdb77a 100644
--- a/contrib/go/_std_1.18/src/hash/crc32/crc32.go
+++ b/contrib/go/_std_1.19/src/hash/crc32/crc32.go
diff --git a/contrib/go/_std_1.19/src/hash/crc32/crc32_amd64.go b/contrib/go/_std_1.19/src/hash/crc32/crc32_amd64.go
new file mode 100644
index 0000000000..6be129f5dd
--- /dev/null
+++ b/contrib/go/_std_1.19/src/hash/crc32/crc32_amd64.go
@@ -0,0 +1,225 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// AMD64-specific hardware-assisted CRC32 algorithms. See crc32.go for a
+// description of the interface that each architecture-specific file
+// implements.
+
+package crc32
+
+import (
+	"internal/cpu"
+	"unsafe"
+)
+
+// This file contains the code to call the SSE 4.2 version of the Castagnoli
+// and IEEE CRC.
+
+// castagnoliSSE42 is defined in crc32_amd64.s and uses the SSE 4.2 CRC32
+// instruction.
+//
+//go:noescape
+func castagnoliSSE42(crc uint32, p []byte) uint32
+
+// castagnoliSSE42Triple is defined in crc32_amd64.s and uses the SSE 4.2 CRC32
+// instruction.
+//
+//go:noescape
+func castagnoliSSE42Triple(
+	crcA, crcB, crcC uint32,
+	a, b, c []byte,
+	rounds uint32,
+) (retA uint32, retB uint32, retC uint32)
+
+// ieeeCLMUL is defined in crc_amd64.s and uses the PCLMULQDQ
+// instruction as well as SSE 4.1.
+//
+//go:noescape
+func ieeeCLMUL(crc uint32, p []byte) uint32
+
+const castagnoliK1 = 168
+const castagnoliK2 = 1344
+
+type sse42Table [4]Table
+
+var castagnoliSSE42TableK1 *sse42Table
+var castagnoliSSE42TableK2 *sse42Table
+
+func archAvailableCastagnoli() bool {
+	return cpu.X86.HasSSE42
+}
+
+func archInitCastagnoli() {
+	if !cpu.X86.HasSSE42 {
+		panic("arch-specific Castagnoli not available")
+	}
+	castagnoliSSE42TableK1 = new(sse42Table)
+	castagnoliSSE42TableK2 = new(sse42Table)
+	// See description in updateCastagnoli.
+	//    t[0][i] = CRC(i000, O)
+	//    t[1][i] = CRC(0i00, O)
+	//    t[2][i] = CRC(00i0, O)
+	//    t[3][i] = CRC(000i, O)
+	// where O is a sequence of K zeros.
+	var tmp [castagnoliK2]byte
+	for b := 0; b < 4; b++ {
+		for i := 0; i < 256; i++ {
+			val := uint32(i) << uint32(b*8)
+			castagnoliSSE42TableK1[b][i] = castagnoliSSE42(val, tmp[:castagnoliK1])
+			castagnoliSSE42TableK2[b][i] = castagnoliSSE42(val, tmp[:])
+		}
+	}
+}
+
+// castagnoliShift computes the CRC32-C of K1 or K2 zeroes (depending on the
+// table given) with the given initial crc value. This corresponds to
+// CRC(crc, O) in the description in updateCastagnoli.
+func castagnoliShift(table *sse42Table, crc uint32) uint32 {
+	return table[3][crc>>24] ^
+		table[2][(crc>>16)&0xFF] ^
+		table[1][(crc>>8)&0xFF] ^
+		table[0][crc&0xFF]
+}
+
+func archUpdateCastagnoli(crc uint32, p []byte) uint32 {
+	if !cpu.X86.HasSSE42 {
+		panic("not available")
+	}
+
+	// This method is inspired from the algorithm in Intel's white paper:
+	//    "Fast CRC Computation for iSCSI Polynomial Using CRC32 Instruction"
+	// The same strategy of splitting the buffer in three is used but the
+	// combining calculation is different; the complete derivation is explained
+	// below.
+	//
+	// -- The basic idea --
+	//
+	// The CRC32 instruction (available in SSE4.2) can process 8 bytes at a
+	// time. In recent Intel architectures the instruction takes 3 cycles;
+	// however the processor can pipeline up to three instructions if they
+	// don't depend on each other.
+	//
+	// Roughly this means that we can process three buffers in about the same
+	// time we can process one buffer.
+	//
+	// The idea is then to split the buffer in three, CRC the three pieces
+	// separately and then combine the results.
+	//
+	// Combining the results requires precomputed tables, so we must choose a
+	// fixed buffer length to optimize. The longer the length, the faster; but
+	// only buffers longer than this length will use the optimization. We choose
+	// two cutoffs and compute tables for both:
+	//  - one around 512: 168*3=504
+	//  - one around 4KB: 1344*3=4032
+	//
+	// -- The nitty gritty --
+	//
+	// Let CRC(I, X) be the non-inverted CRC32-C of the sequence X (with
+	// initial non-inverted CRC I). This function has the following properties:
+	//   (a) CRC(I, AB) = CRC(CRC(I, A), B)
+	//   (b) CRC(I, A xor B) = CRC(I, A) xor CRC(0, B)
+	//
+	// Say we want to compute CRC(I, ABC) where A, B, C are three sequences of
+	// K bytes each, where K is a fixed constant. Let O be the sequence of K zero
+	// bytes.
+	//
+	// CRC(I, ABC) = CRC(I, ABO xor C)
+	//             = CRC(I, ABO) xor CRC(0, C)
+	//             = CRC(CRC(I, AB), O) xor CRC(0, C)
+	//             = CRC(CRC(I, AO xor B), O) xor CRC(0, C)
+	//             = CRC(CRC(I, AO) xor CRC(0, B), O) xor CRC(0, C)
+	//             = CRC(CRC(CRC(I, A), O) xor CRC(0, B), O) xor CRC(0, C)
+	//
+	// The castagnoliSSE42Triple function can compute CRC(I, A), CRC(0, B),
+	// and CRC(0, C) efficiently.  We just need to find a way to quickly compute
+	// CRC(uvwx, O) given a 4-byte initial value uvwx. We can precompute these
+	// values; since we can't have a 32-bit table, we break it up into four
+	// 8-bit tables:
+	//
+	//    CRC(uvwx, O) = CRC(u000, O) xor
+	//                   CRC(0v00, O) xor
+	//                   CRC(00w0, O) xor
+	//                   CRC(000x, O)
+	//
+	// We can compute tables corresponding to the four terms for all 8-bit
+	// values.
+
+	crc = ^crc
+
+	// If a buffer is long enough to use the optimization, process the first few
+	// bytes to align the buffer to an 8 byte boundary (if necessary).
+	if len(p) >= castagnoliK1*3 {
+		delta := int(uintptr(unsafe.Pointer(&p[0])) & 7)
+		if delta != 0 {
+			delta = 8 - delta
+			crc = castagnoliSSE42(crc, p[:delta])
+			p = p[delta:]
+		}
+	}
+
+	// Process 3*K2 at a time.
+	for len(p) >= castagnoliK2*3 {
+		// Compute CRC(I, A), CRC(0, B), and CRC(0, C).
+		crcA, crcB, crcC := castagnoliSSE42Triple(
+			crc, 0, 0,
+			p, p[castagnoliK2:], p[castagnoliK2*2:],
+			castagnoliK2/24)
+
+		// CRC(I, AB) = CRC(CRC(I, A), O) xor CRC(0, B)
+		crcAB := castagnoliShift(castagnoliSSE42TableK2, crcA) ^ crcB
+		// CRC(I, ABC) = CRC(CRC(I, AB), O) xor CRC(0, C)
+		crc = castagnoliShift(castagnoliSSE42TableK2, crcAB) ^ crcC
+		p = p[castagnoliK2*3:]
+	}
+
+	// Process 3*K1 at a time.
+	for len(p) >= castagnoliK1*3 {
+		// Compute CRC(I, A), CRC(0, B), and CRC(0, C).
+		crcA, crcB, crcC := castagnoliSSE42Triple(
+			crc, 0, 0,
+			p, p[castagnoliK1:], p[castagnoliK1*2:],
+			castagnoliK1/24)
+
+		// CRC(I, AB) = CRC(CRC(I, A), O) xor CRC(0, B)
+		crcAB := castagnoliShift(castagnoliSSE42TableK1, crcA) ^ crcB
+		// CRC(I, ABC) = CRC(CRC(I, AB), O) xor CRC(0, C)
+		crc = castagnoliShift(castagnoliSSE42TableK1, crcAB) ^ crcC
+		p = p[castagnoliK1*3:]
+	}
+
+	// Use the simple implementation for what's left.
+	crc = castagnoliSSE42(crc, p)
+	return ^crc
+}
+
+func archAvailableIEEE() bool {
+	return cpu.X86.HasPCLMULQDQ && cpu.X86.HasSSE41
+}
+
+var archIeeeTable8 *slicing8Table
+
+func archInitIEEE() {
+	if !cpu.X86.HasPCLMULQDQ || !cpu.X86.HasSSE41 {
+		panic("not available")
+	}
+	// We still use slicing-by-8 for small buffers.
+	archIeeeTable8 = slicingMakeTable(IEEE)
+}
+
+func archUpdateIEEE(crc uint32, p []byte) uint32 {
+	if !cpu.X86.HasPCLMULQDQ || !cpu.X86.HasSSE41 {
+		panic("not available")
+	}
+
+	if len(p) >= 64 {
+		left := len(p) & 15
+		do := len(p) - left
+		crc = ^ieeeCLMUL(^crc, p[:do])
+		p = p[do:]
+	}
+	if len(p) == 0 {
+		return crc
+	}
+	return slicingUpdate(crc, archIeeeTable8, p)
+}
diff --git a/contrib/go/_std_1.18/src/hash/crc32/crc32_amd64.s b/contrib/go/_std_1.19/src/hash/crc32/crc32_amd64.s
index 6af6c253a7..6af6c253a7 100644
--- a/contrib/go/_std_1.18/src/hash/crc32/crc32_amd64.s
+++ b/contrib/go/_std_1.19/src/hash/crc32/crc32_amd64.s
diff --git a/contrib/go/_std_1.18/src/hash/crc32/crc32_generic.go b/contrib/go/_std_1.19/src/hash/crc32/crc32_generic.go
index abacbb663d..abacbb663d 100644
--- a/contrib/go/_std_1.18/src/hash/crc32/crc32_generic.go
+++ b/contrib/go/_std_1.19/src/hash/crc32/crc32_generic.go
diff --git a/contrib/go/_std_1.18/src/hash/hash.go b/contrib/go/_std_1.19/src/hash/hash.go
index 62cf6a4518..62cf6a4518 100644
--- a/contrib/go/_std_1.18/src/hash/hash.go
+++ b/contrib/go/_std_1.19/src/hash/hash.go
diff --git a/contrib/go/_std_1.18/src/internal/abi/abi.go b/contrib/go/_std_1.19/src/internal/abi/abi.go
index 11acac346f..11acac346f 100644
--- a/contrib/go/_std_1.18/src/internal/abi/abi.go
+++ b/contrib/go/_std_1.19/src/internal/abi/abi.go
diff --git a/contrib/go/_std_1.18/src/internal/abi/abi_amd64.go b/contrib/go/_std_1.19/src/internal/abi/abi_amd64.go
index d3c5678223..d3c5678223 100644
--- a/contrib/go/_std_1.18/src/internal/abi/abi_amd64.go
+++ b/contrib/go/_std_1.19/src/internal/abi/abi_amd64.go
diff --git a/contrib/go/_std_1.18/src/internal/abi/abi_test.s b/contrib/go/_std_1.19/src/internal/abi/abi_test.s
index 93ace3ef48..93ace3ef48 100644
--- a/contrib/go/_std_1.18/src/internal/abi/abi_test.s
+++ b/contrib/go/_std_1.19/src/internal/abi/abi_test.s
diff --git a/contrib/go/_std_1.18/src/internal/bytealg/bytealg.go b/contrib/go/_std_1.19/src/internal/bytealg/bytealg.go
index ebebce75fe..ebebce75fe 100644
--- a/contrib/go/_std_1.18/src/internal/bytealg/bytealg.go
+++ b/contrib/go/_std_1.19/src/internal/bytealg/bytealg.go
diff --git a/contrib/go/_std_1.18/src/internal/bytealg/compare_amd64.s b/contrib/go/_std_1.19/src/internal/bytealg/compare_amd64.s
index 4ccaca5e87..4ccaca5e87 100644
--- a/contrib/go/_std_1.18/src/internal/bytealg/compare_amd64.s
+++ b/contrib/go/_std_1.19/src/internal/bytealg/compare_amd64.s
diff --git a/contrib/go/_std_1.19/src/internal/bytealg/compare_native.go b/contrib/go/_std_1.19/src/internal/bytealg/compare_native.go
new file mode 100644
index 0000000000..34964e281c
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/bytealg/compare_native.go
@@ -0,0 +1,19 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build 386 || amd64 || s390x || arm || arm64 || loong64 || ppc64 || ppc64le || mips || mipsle || wasm || mips64 || mips64le || riscv64
+
+package bytealg
+
+import _ "unsafe" // For go:linkname
+
+//go:noescape
+func Compare(a, b []byte) int
+
+// The declaration below generates ABI wrappers for functions
+// implemented in assembly in this package but declared in another
+// package.
+
+//go:linkname abigen_runtime_cmpstring runtime.cmpstring
+func abigen_runtime_cmpstring(a, b string) int
diff --git a/contrib/go/_std_1.18/src/internal/bytealg/count_amd64.s b/contrib/go/_std_1.19/src/internal/bytealg/count_amd64.s
index fa864c4c76..fa864c4c76 100644
--- a/contrib/go/_std_1.18/src/internal/bytealg/count_amd64.s
+++ b/contrib/go/_std_1.19/src/internal/bytealg/count_amd64.s
diff --git a/contrib/go/_std_1.18/src/internal/bytealg/count_native.go b/contrib/go/_std_1.19/src/internal/bytealg/count_native.go
index 90189c9fe0..90189c9fe0 100644
--- a/contrib/go/_std_1.18/src/internal/bytealg/count_native.go
+++ b/contrib/go/_std_1.19/src/internal/bytealg/count_native.go
diff --git a/contrib/go/_std_1.18/src/internal/bytealg/equal_amd64.s b/contrib/go/_std_1.19/src/internal/bytealg/equal_amd64.s
index dd46e2e0fd..dd46e2e0fd 100644
--- a/contrib/go/_std_1.18/src/internal/bytealg/equal_amd64.s
+++ b/contrib/go/_std_1.19/src/internal/bytealg/equal_amd64.s
diff --git a/contrib/go/_std_1.18/src/internal/bytealg/equal_generic.go b/contrib/go/_std_1.19/src/internal/bytealg/equal_generic.go
index 59bdf8fdd5..59bdf8fdd5 100644
--- a/contrib/go/_std_1.18/src/internal/bytealg/equal_generic.go
+++ b/contrib/go/_std_1.19/src/internal/bytealg/equal_generic.go
diff --git a/contrib/go/_std_1.18/src/internal/bytealg/equal_native.go b/contrib/go/_std_1.19/src/internal/bytealg/equal_native.go
index cf3a245bc0..cf3a245bc0 100644
--- a/contrib/go/_std_1.18/src/internal/bytealg/equal_native.go
+++ b/contrib/go/_std_1.19/src/internal/bytealg/equal_native.go
diff --git a/contrib/go/_std_1.18/src/internal/bytealg/index_amd64.go b/contrib/go/_std_1.19/src/internal/bytealg/index_amd64.go
index c7a1941e5f..c7a1941e5f 100644
--- a/contrib/go/_std_1.18/src/internal/bytealg/index_amd64.go
+++ b/contrib/go/_std_1.19/src/internal/bytealg/index_amd64.go
diff --git a/contrib/go/_std_1.18/src/internal/bytealg/index_amd64.s b/contrib/go/_std_1.19/src/internal/bytealg/index_amd64.s
index 6193b57239..6193b57239 100644
--- a/contrib/go/_std_1.18/src/internal/bytealg/index_amd64.s
+++ b/contrib/go/_std_1.19/src/internal/bytealg/index_amd64.s
diff --git a/contrib/go/_std_1.18/src/internal/bytealg/index_native.go b/contrib/go/_std_1.19/src/internal/bytealg/index_native.go
index 6e4a2f39e4..6e4a2f39e4 100644
--- a/contrib/go/_std_1.18/src/internal/bytealg/index_native.go
+++ b/contrib/go/_std_1.19/src/internal/bytealg/index_native.go
diff --git a/contrib/go/_std_1.18/src/internal/bytealg/indexbyte_amd64.s b/contrib/go/_std_1.19/src/internal/bytealg/indexbyte_amd64.s
index f78093c539..f78093c539 100644
--- a/contrib/go/_std_1.18/src/internal/bytealg/indexbyte_amd64.s
+++ b/contrib/go/_std_1.19/src/internal/bytealg/indexbyte_amd64.s
diff --git a/contrib/go/_std_1.19/src/internal/bytealg/indexbyte_native.go b/contrib/go/_std_1.19/src/internal/bytealg/indexbyte_native.go
new file mode 100644
index 0000000000..c5bb2df5ea
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/bytealg/indexbyte_native.go
@@ -0,0 +1,13 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build 386 || amd64 || s390x || arm || arm64 || loong64 || ppc64 || ppc64le || mips || mipsle || mips64 || mips64le || riscv64 || wasm
+
+package bytealg
+
+//go:noescape
+func IndexByte(b []byte, c byte) int
+
+//go:noescape
+func IndexByteString(s string, c byte) int
diff --git a/contrib/go/_std_1.19/src/internal/cpu/cpu.go b/contrib/go/_std_1.19/src/internal/cpu/cpu.go
new file mode 100644
index 0000000000..ae23b59617
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/cpu/cpu.go
@@ -0,0 +1,221 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package cpu implements processor feature detection
+// used by the Go standard library.
+package cpu
+
+// DebugOptions is set to true by the runtime if the OS supports reading
+// GODEBUG early in runtime startup.
+// This should not be changed after it is initialized.
+var DebugOptions bool
+
+// CacheLinePad is used to pad structs to avoid false sharing.
+type CacheLinePad struct{ _ [CacheLinePadSize]byte }
+
+// CacheLineSize is the CPU's assumed cache line size.
+// There is currently no runtime detection of the real cache line size
+// so we use the constant per GOARCH CacheLinePadSize as an approximation.
+var CacheLineSize uintptr = CacheLinePadSize
+
+// The booleans in X86 contain the correspondingly named cpuid feature bit.
+// HasAVX and HasAVX2 are only set if the OS does support XMM and YMM registers
+// in addition to the cpuid feature bit being set.
+// The struct is padded to avoid false sharing.
+var X86 struct {
+	_            CacheLinePad
+	HasAES       bool
+	HasADX       bool
+	HasAVX       bool
+	HasAVX2      bool
+	HasBMI1      bool
+	HasBMI2      bool
+	HasERMS      bool
+	HasFMA       bool
+	HasOSXSAVE   bool
+	HasPCLMULQDQ bool
+	HasPOPCNT    bool
+	HasRDTSCP    bool
+	HasSSE3      bool
+	HasSSSE3     bool
+	HasSSE41     bool
+	HasSSE42     bool
+	_            CacheLinePad
+}
+
+// The booleans in ARM contain the correspondingly named cpu feature bit.
+// The struct is padded to avoid false sharing.
+var ARM struct {
+	_        CacheLinePad
+	HasVFPv4 bool
+	HasIDIVA bool
+	_        CacheLinePad
+}
+
+// The booleans in ARM64 contain the correspondingly named cpu feature bit.
+// The struct is padded to avoid false sharing.
+var ARM64 struct {
+	_            CacheLinePad
+	HasAES       bool
+	HasPMULL     bool
+	HasSHA1      bool
+	HasSHA2      bool
+	HasCRC32     bool
+	HasATOMICS   bool
+	HasCPUID     bool
+	IsNeoverseN1 bool
+	IsZeus       bool
+	_            CacheLinePad
+}
+
+var MIPS64X struct {
+	_      CacheLinePad
+	HasMSA bool // MIPS SIMD architecture
+	_      CacheLinePad
+}
+
+// For ppc64(le), it is safe to check only for ISA level starting on ISA v3.00,
+// since there are no optional categories. There are some exceptions that also
+// require kernel support to work (darn, scv), so there are feature bits for
+// those as well. The minimum processor requirement is POWER8 (ISA 2.07).
+// The struct is padded to avoid false sharing.
+var PPC64 struct {
+	_         CacheLinePad
+	HasDARN   bool // Hardware random number generator (requires kernel enablement)
+	HasSCV    bool // Syscall vectored (requires kernel enablement)
+	IsPOWER8  bool // ISA v2.07 (POWER8)
+	IsPOWER9  bool // ISA v3.00 (POWER9)
+	IsPOWER10 bool // ISA v3.1  (POWER10)
+	_         CacheLinePad
+}
+
+var S390X struct {
+	_         CacheLinePad
+	HasZARCH  bool // z architecture mode is active [mandatory]
+	HasSTFLE  bool // store facility list extended [mandatory]
+	HasLDISP  bool // long (20-bit) displacements [mandatory]
+	HasEIMM   bool // 32-bit immediates [mandatory]
+	HasDFP    bool // decimal floating point
+	HasETF3EH bool // ETF-3 enhanced
+	HasMSA    bool // message security assist (CPACF)
+	HasAES    bool // KM-AES{128,192,256} functions
+	HasAESCBC bool // KMC-AES{128,192,256} functions
+	HasAESCTR bool // KMCTR-AES{128,192,256} functions
+	HasAESGCM bool // KMA-GCM-AES{128,192,256} functions
+	HasGHASH  bool // KIMD-GHASH function
+	HasSHA1   bool // K{I,L}MD-SHA-1 functions
+	HasSHA256 bool // K{I,L}MD-SHA-256 functions
+	HasSHA512 bool // K{I,L}MD-SHA-512 functions
+	HasSHA3   bool // K{I,L}MD-SHA3-{224,256,384,512} and K{I,L}MD-SHAKE-{128,256} functions
+	HasVX     bool // vector facility. Note: the runtime sets this when it processes auxv records.
+	HasVXE    bool // vector-enhancements facility 1
+	HasKDSA   bool // elliptic curve functions
+	HasECDSA  bool // NIST curves
+	HasEDDSA  bool // Edwards curves
+	_         CacheLinePad
+}
+
+// Initialize examines the processor and sets the relevant variables above.
+// This is called by the runtime package early in program initialization,
+// before normal init functions are run. env is set by runtime if the OS supports
+// cpu feature options in GODEBUG.
+func Initialize(env string) {
+	doinit()
+	processOptions(env)
+}
+
+// options contains the cpu debug options that can be used in GODEBUG.
+// Options are arch dependent and are added by the arch specific doinit functions.
+// Features that are mandatory for the specific GOARCH should not be added to options
+// (e.g. SSE2 on amd64).
+var options []option
+
+// Option names should be lower case. e.g. avx instead of AVX.
+type option struct {
+	Name      string
+	Feature   *bool
+	Specified bool // whether feature value was specified in GODEBUG
+	Enable    bool // whether feature should be enabled
+}
+
+// processOptions enables or disables CPU feature values based on the parsed env string.
+// The env string is expected to be of the form cpu.feature1=value1,cpu.feature2=value2...
+// where feature names is one of the architecture specific list stored in the
+// cpu packages options variable and values are either 'on' or 'off'.
+// If env contains cpu.all=off then all cpu features referenced through the options
+// variable are disabled. Other feature names and values result in warning messages.
+func processOptions(env string) {
+field:
+	for env != "" {
+		field := ""
+		i := indexByte(env, ',')
+		if i < 0 {
+			field, env = env, ""
+		} else {
+			field, env = env[:i], env[i+1:]
+		}
+		if len(field) < 4 || field[:4] != "cpu." {
+			continue
+		}
+		i = indexByte(field, '=')
+		if i < 0 {
+			print("GODEBUG: no value specified for \"", field, "\"\n")
+			continue
+		}
+		key, value := field[4:i], field[i+1:] // e.g. "SSE2", "on"
+
+		var enable bool
+		switch value {
+		case "on":
+			enable = true
+		case "off":
+			enable = false
+		default:
+			print("GODEBUG: value \"", value, "\" not supported for cpu option \"", key, "\"\n")
+			continue field
+		}
+
+		if key == "all" {
+			for i := range options {
+				options[i].Specified = true
+				options[i].Enable = enable
+			}
+			continue field
+		}
+
+		for i := range options {
+			if options[i].Name == key {
+				options[i].Specified = true
+				options[i].Enable = enable
+				continue field
+			}
+		}
+
+		print("GODEBUG: unknown cpu feature \"", key, "\"\n")
+	}
+
+	for _, o := range options {
+		if !o.Specified {
+			continue
+		}
+
+		if o.Enable && !*o.Feature {
+			print("GODEBUG: can not enable \"", o.Name, "\", missing CPU support\n")
+			continue
+		}
+
+		*o.Feature = o.Enable
+	}
+}
+
+// indexByte returns the index of the first instance of c in s,
+// or -1 if c is not present in s.
+func indexByte(s string, c byte) int {
+	for i := 0; i < len(s); i++ {
+		if s[i] == c {
+			return i
+		}
+	}
+	return -1
+}
diff --git a/contrib/go/_std_1.18/src/internal/cpu/cpu.s b/contrib/go/_std_1.19/src/internal/cpu/cpu.s
index 3c770c132d..3c770c132d 100644
--- a/contrib/go/_std_1.18/src/internal/cpu/cpu.s
+++ b/contrib/go/_std_1.19/src/internal/cpu/cpu.s
diff --git a/contrib/go/_std_1.19/src/internal/cpu/cpu_x86.go b/contrib/go/_std_1.19/src/internal/cpu/cpu_x86.go
new file mode 100644
index 0000000000..6fd979a747
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/cpu/cpu_x86.go
@@ -0,0 +1,187 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build 386 || amd64
+
+package cpu
+
+const CacheLinePadSize = 64
+
+// cpuid is implemented in cpu_x86.s.
+func cpuid(eaxArg, ecxArg uint32) (eax, ebx, ecx, edx uint32)
+
+// xgetbv with ecx = 0 is implemented in cpu_x86.s.
+func xgetbv() (eax, edx uint32)
+
+// getGOAMD64level is implemented in cpu_x86.s. Returns number in [1,4].
+func getGOAMD64level() int32
+
+const (
+	// edx bits
+	cpuid_SSE2 = 1 << 26
+
+	// ecx bits
+	cpuid_SSE3      = 1 << 0
+	cpuid_PCLMULQDQ = 1 << 1
+	cpuid_SSSE3     = 1 << 9
+	cpuid_FMA       = 1 << 12
+	cpuid_SSE41     = 1 << 19
+	cpuid_SSE42     = 1 << 20
+	cpuid_POPCNT    = 1 << 23
+	cpuid_AES       = 1 << 25
+	cpuid_OSXSAVE   = 1 << 27
+	cpuid_AVX       = 1 << 28
+
+	// ebx bits
+	cpuid_BMI1 = 1 << 3
+	cpuid_AVX2 = 1 << 5
+	cpuid_BMI2 = 1 << 8
+	cpuid_ERMS = 1 << 9
+	cpuid_ADX  = 1 << 19
+
+	// edx bits for CPUID 0x80000001
+	cpuid_RDTSCP = 1 << 27
+)
+
+var maxExtendedFunctionInformation uint32
+
+func doinit() {
+	options = []option{
+		{Name: "adx", Feature: &X86.HasADX},
+		{Name: "aes", Feature: &X86.HasAES},
+		{Name: "erms", Feature: &X86.HasERMS},
+		{Name: "pclmulqdq", Feature: &X86.HasPCLMULQDQ},
+		{Name: "rdtscp", Feature: &X86.HasRDTSCP},
+	}
+	level := getGOAMD64level()
+	if level < 2 {
+		// These options are required at level 2. At lower levels
+		// they can be turned off.
+		options = append(options,
+			option{Name: "popcnt", Feature: &X86.HasPOPCNT},
+			option{Name: "sse3", Feature: &X86.HasSSE3},
+			option{Name: "sse41", Feature: &X86.HasSSE41},
+			option{Name: "sse42", Feature: &X86.HasSSE42},
+			option{Name: "ssse3", Feature: &X86.HasSSSE3})
+	}
+	if level < 3 {
+		// These options are required at level 3. At lower levels
+		// they can be turned off.
+		options = append(options,
+			option{Name: "avx", Feature: &X86.HasAVX},
+			option{Name: "avx2", Feature: &X86.HasAVX2},
+			option{Name: "bmi1", Feature: &X86.HasBMI1},
+			option{Name: "bmi2", Feature: &X86.HasBMI2},
+			option{Name: "fma", Feature: &X86.HasFMA})
+	}
+
+	maxID, _, _, _ := cpuid(0, 0)
+
+	if maxID < 1 {
+		return
+	}
+
+	maxExtendedFunctionInformation, _, _, _ = cpuid(0x80000000, 0)
+
+	_, _, ecx1, _ := cpuid(1, 0)
+
+	X86.HasSSE3 = isSet(ecx1, cpuid_SSE3)
+	X86.HasPCLMULQDQ = isSet(ecx1, cpuid_PCLMULQDQ)
+	X86.HasSSSE3 = isSet(ecx1, cpuid_SSSE3)
+	X86.HasSSE41 = isSet(ecx1, cpuid_SSE41)
+	X86.HasSSE42 = isSet(ecx1, cpuid_SSE42)
+	X86.HasPOPCNT = isSet(ecx1, cpuid_POPCNT)
+	X86.HasAES = isSet(ecx1, cpuid_AES)
+
+	// OSXSAVE can be false when using older Operating Systems
+	// or when explicitly disabled on newer Operating Systems by
+	// e.g. setting the xsavedisable boot option on Windows 10.
+	X86.HasOSXSAVE = isSet(ecx1, cpuid_OSXSAVE)
+
+	// The FMA instruction set extension only has VEX prefixed instructions.
+	// VEX prefixed instructions require OSXSAVE to be enabled.
+	// See Intel 64 and IA-32 Architecture Software Developer’s Manual Volume 2
+	// Section 2.4 "AVX and SSE Instruction Exception Specification"
+	X86.HasFMA = isSet(ecx1, cpuid_FMA) && X86.HasOSXSAVE
+
+	osSupportsAVX := false
+	// For XGETBV, OSXSAVE bit is required and sufficient.
+	if X86.HasOSXSAVE {
+		eax, _ := xgetbv()
+		// Check if XMM and YMM registers have OS support.
+		osSupportsAVX = isSet(eax, 1<<1) && isSet(eax, 1<<2)
+	}
+
+	X86.HasAVX = isSet(ecx1, cpuid_AVX) && osSupportsAVX
+
+	if maxID < 7 {
+		return
+	}
+
+	_, ebx7, _, _ := cpuid(7, 0)
+	X86.HasBMI1 = isSet(ebx7, cpuid_BMI1)
+	X86.HasAVX2 = isSet(ebx7, cpuid_AVX2) && osSupportsAVX
+	X86.HasBMI2 = isSet(ebx7, cpuid_BMI2)
+	X86.HasERMS = isSet(ebx7, cpuid_ERMS)
+	X86.HasADX = isSet(ebx7, cpuid_ADX)
+
+	var maxExtendedInformation uint32
+	maxExtendedInformation, _, _, _ = cpuid(0x80000000, 0)
+
+	if maxExtendedInformation < 0x80000001 {
+		return
+	}
+
+	_, _, _, edxExt1 := cpuid(0x80000001, 0)
+	X86.HasRDTSCP = isSet(edxExt1, cpuid_RDTSCP)
+}
+
+func isSet(hwc uint32, value uint32) bool {
+	return hwc&value != 0
+}
+
+// Name returns the CPU name given by the vendor.
+// If the CPU name can not be determined an
+// empty string is returned.
+func Name() string {
+	if maxExtendedFunctionInformation < 0x80000004 {
+		return ""
+	}
+
+	data := make([]byte, 0, 3*4*4)
+
+	var eax, ebx, ecx, edx uint32
+	eax, ebx, ecx, edx = cpuid(0x80000002, 0)
+	data = appendBytes(data, eax, ebx, ecx, edx)
+	eax, ebx, ecx, edx = cpuid(0x80000003, 0)
+	data = appendBytes(data, eax, ebx, ecx, edx)
+	eax, ebx, ecx, edx = cpuid(0x80000004, 0)
+	data = appendBytes(data, eax, ebx, ecx, edx)
+
+	// Trim leading spaces.
+	for len(data) > 0 && data[0] == ' ' {
+		data = data[1:]
+	}
+
+	// Trim tail after and including the first null byte.
+	for i, c := range data {
+		if c == '\x00' {
+			data = data[:i]
+			break
+		}
+	}
+
+	return string(data)
+}
+
+func appendBytes(b []byte, args ...uint32) []byte {
+	for _, arg := range args {
+		b = append(b,
+			byte((arg >> 0)),
+			byte((arg >> 8)),
+			byte((arg >> 16)),
+			byte((arg >> 24)))
+	}
+	return b
+}
diff --git a/contrib/go/_std_1.19/src/internal/cpu/cpu_x86.s b/contrib/go/_std_1.19/src/internal/cpu/cpu_x86.s
new file mode 100644
index 0000000000..2ee8eca248
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/cpu/cpu_x86.s
@@ -0,0 +1,43 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build 386 || amd64
+
+#include "textflag.h"
+
+// func cpuid(eaxArg, ecxArg uint32) (eax, ebx, ecx, edx uint32)
+TEXT ·cpuid(SB), NOSPLIT, $0-24
+	MOVL eaxArg+0(FP), AX
+	MOVL ecxArg+4(FP), CX
+	CPUID
+	MOVL AX, eax+8(FP)
+	MOVL BX, ebx+12(FP)
+	MOVL CX, ecx+16(FP)
+	MOVL DX, edx+20(FP)
+	RET
+
+// func xgetbv() (eax, edx uint32)
+TEXT ·xgetbv(SB),NOSPLIT,$0-8
+	MOVL $0, CX
+	XGETBV
+	MOVL AX, eax+0(FP)
+	MOVL DX, edx+4(FP)
+	RET
+
+// func getGOAMD64level() int32
+TEXT ·getGOAMD64level(SB),NOSPLIT,$0-4
+#ifdef GOAMD64_v4
+	MOVL $4, ret+0(FP)
+#else
+#ifdef GOAMD64_v3
+	MOVL $3, ret+0(FP)
+#else
+#ifdef GOAMD64_v2
+	MOVL $2, ret+0(FP)
+#else
+	MOVL $1, ret+0(FP)
+#endif
+#endif
+#endif
+	RET
diff --git a/contrib/go/_std_1.19/src/internal/fmtsort/sort.go b/contrib/go/_std_1.19/src/internal/fmtsort/sort.go
new file mode 100644
index 0000000000..278a89bd75
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/fmtsort/sort.go
@@ -0,0 +1,219 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package fmtsort provides a general stable ordering mechanism
+// for maps, on behalf of the fmt and text/template packages.
+// It is not guaranteed to be efficient and works only for types
+// that are valid map keys.
+package fmtsort
+
+import (
+	"reflect"
+	"sort"
+)
+
+// Note: Throughout this package we avoid calling reflect.Value.Interface as
+// it is not always legal to do so and it's easier to avoid the issue than to face it.
+
+// SortedMap represents a map's keys and values. The keys and values are
+// aligned in index order: Value[i] is the value in the map corresponding to Key[i].
+type SortedMap struct {
+	Key   []reflect.Value
+	Value []reflect.Value
+}
+
+func (o *SortedMap) Len() int           { return len(o.Key) }
+func (o *SortedMap) Less(i, j int) bool { return compare(o.Key[i], o.Key[j]) < 0 }
+func (o *SortedMap) Swap(i, j int) {
+	o.Key[i], o.Key[j] = o.Key[j], o.Key[i]
+	o.Value[i], o.Value[j] = o.Value[j], o.Value[i]
+}
+
+// Sort accepts a map and returns a SortedMap that has the same keys and
+// values but in a stable sorted order according to the keys, modulo issues
+// raised by unorderable key values such as NaNs.
+//
+// The ordering rules are more general than with Go's < operator:
+//
+//   - when applicable, nil compares low
+//   - ints, floats, and strings order by <
+//   - NaN compares less than non-NaN floats
+//   - bool compares false before true
+//   - complex compares real, then imag
+//   - pointers compare by machine address
+//   - channel values compare by machine address
+//   - structs compare each field in turn
+//   - arrays compare each element in turn.
+//     Otherwise identical arrays compare by length.
+//   - interface values compare first by reflect.Type describing the concrete type
+//     and then by concrete value as described in the previous rules.
+func Sort(mapValue reflect.Value) *SortedMap {
+	if mapValue.Type().Kind() != reflect.Map {
+		return nil
+	}
+	// Note: this code is arranged to not panic even in the presence
+	// of a concurrent map update. The runtime is responsible for
+	// yelling loudly if that happens. See issue 33275.
+	n := mapValue.Len()
+	key := make([]reflect.Value, 0, n)
+	value := make([]reflect.Value, 0, n)
+	iter := mapValue.MapRange()
+	for iter.Next() {
+		key = append(key, iter.Key())
+		value = append(value, iter.Value())
+	}
+	sorted := &SortedMap{
+		Key:   key,
+		Value: value,
+	}
+	sort.Stable(sorted)
+	return sorted
+}
+
+// compare compares two values of the same type. It returns -1, 0, 1
+// according to whether a > b (1), a == b (0), or a < b (-1).
+// If the types differ, it returns -1.
+// See the comment on Sort for the comparison rules.
+func compare(aVal, bVal reflect.Value) int {
+	aType, bType := aVal.Type(), bVal.Type()
+	if aType != bType {
+		return -1 // No good answer possible, but don't return 0: they're not equal.
+	}
+	switch aVal.Kind() {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		a, b := aVal.Int(), bVal.Int()
+		switch {
+		case a < b:
+			return -1
+		case a > b:
+			return 1
+		default:
+			return 0
+		}
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		a, b := aVal.Uint(), bVal.Uint()
+		switch {
+		case a < b:
+			return -1
+		case a > b:
+			return 1
+		default:
+			return 0
+		}
+	case reflect.String:
+		a, b := aVal.String(), bVal.String()
+		switch {
+		case a < b:
+			return -1
+		case a > b:
+			return 1
+		default:
+			return 0
+		}
+	case reflect.Float32, reflect.Float64:
+		return floatCompare(aVal.Float(), bVal.Float())
+	case reflect.Complex64, reflect.Complex128:
+		a, b := aVal.Complex(), bVal.Complex()
+		if c := floatCompare(real(a), real(b)); c != 0 {
+			return c
+		}
+		return floatCompare(imag(a), imag(b))
+	case reflect.Bool:
+		a, b := aVal.Bool(), bVal.Bool()
+		switch {
+		case a == b:
+			return 0
+		case a:
+			return 1
+		default:
+			return -1
+		}
+	case reflect.Pointer, reflect.UnsafePointer:
+		a, b := aVal.Pointer(), bVal.Pointer()
+		switch {
+		case a < b:
+			return -1
+		case a > b:
+			return 1
+		default:
+			return 0
+		}
+	case reflect.Chan:
+		if c, ok := nilCompare(aVal, bVal); ok {
+			return c
+		}
+		ap, bp := aVal.Pointer(), bVal.Pointer()
+		switch {
+		case ap < bp:
+			return -1
+		case ap > bp:
+			return 1
+		default:
+			return 0
+		}
+	case reflect.Struct:
+		for i := 0; i < aVal.NumField(); i++ {
+			if c := compare(aVal.Field(i), bVal.Field(i)); c != 0 {
+				return c
+			}
+		}
+		return 0
+	case reflect.Array:
+		for i := 0; i < aVal.Len(); i++ {
+			if c := compare(aVal.Index(i), bVal.Index(i)); c != 0 {
+				return c
+			}
+		}
+		return 0
+	case reflect.Interface:
+		if c, ok := nilCompare(aVal, bVal); ok {
+			return c
+		}
+		c := compare(reflect.ValueOf(aVal.Elem().Type()), reflect.ValueOf(bVal.Elem().Type()))
+		if c != 0 {
+			return c
+		}
+		return compare(aVal.Elem(), bVal.Elem())
+	default:
+		// Certain types cannot appear as keys (maps, funcs, slices), but be explicit.
+		panic("bad type in compare: " + aType.String())
+	}
+}
+
+// nilCompare checks whether either value is nil. If not, the boolean is false.
+// If either value is nil, the boolean is true and the integer is the comparison
+// value. The comparison is defined to be 0 if both are nil, otherwise the one
+// nil value compares low. Both arguments must represent a chan, func,
+// interface, map, pointer, or slice.
+func nilCompare(aVal, bVal reflect.Value) (int, bool) {
+	if aVal.IsNil() {
+		if bVal.IsNil() {
+			return 0, true
+		}
+		return -1, true
+	}
+	if bVal.IsNil() {
+		return 1, true
+	}
+	return 0, false
+}
+
+// floatCompare compares two floating-point values. NaNs compare low.
+func floatCompare(a, b float64) int {
+	switch {
+	case isNaN(a):
+		return -1 // No good answer if b is a NaN so don't bother checking.
+	case isNaN(b):
+		return 1
+	case a < b:
+		return -1
+	case a > b:
+		return 1
+	}
+	return 0
+}
+
+func isNaN(a float64) bool {
+	return a != a
+}
diff --git a/contrib/go/_std_1.19/src/internal/goarch/goarch.go b/contrib/go/_std_1.19/src/internal/goarch/goarch.go
new file mode 100644
index 0000000000..3dda62fadc
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/goarch/goarch.go
@@ -0,0 +1,60 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// package goarch contains GOARCH-specific constants.
+package goarch
+
+// The next line makes 'go generate' write the zgoarch*.go files with
+// per-arch information, including constants named $GOARCH for every
+// GOARCH. The constant is 1 on the current system, 0 otherwise; multiplying
+// by them is useful for defining GOARCH-specific constants.
+//
+//go:generate go run gengoarch.go
+
+type ArchFamilyType int
+
+const (
+	AMD64 ArchFamilyType = iota
+	ARM
+	ARM64
+	I386
+	LOONG64
+	MIPS
+	MIPS64
+	PPC64
+	RISCV64
+	S390X
+	WASM
+)
+
+// PtrSize is the size of a pointer in bytes - unsafe.Sizeof(uintptr(0)) but as an ideal constant.
+// It is also the size of the machine's native word size (that is, 4 on 32-bit systems, 8 on 64-bit).
+const PtrSize = 4 << (^uintptr(0) >> 63)
+
+// ArchFamily is the architecture family (AMD64, ARM, ...)
+const ArchFamily ArchFamilyType = _ArchFamily
+
+// BigEndian reports whether the architecture is big-endian.
+const BigEndian = IsArmbe|IsArm64be|IsMips|IsMips64|IsPpc|IsPpc64|IsS390|IsS390x|IsSparc|IsSparc64 == 1
+
+// DefaultPhysPageSize is the default physical page size.
+const DefaultPhysPageSize = _DefaultPhysPageSize
+
+// PCQuantum is the minimal unit for a program counter (1 on x86, 4 on most other systems).
+// The various PC tables record PC deltas pre-divided by PCQuantum.
+const PCQuantum = _PCQuantum
+
+// Int64Align is the required alignment for a 64-bit integer (4 on 32-bit systems, 8 on 64-bit).
+const Int64Align = PtrSize
+
+// MinFrameSize is the size of the system-reserved words at the bottom
+// of a frame (just above the architectural stack pointer).
+// It is zero on x86 and PtrSize on most non-x86 (LR-based) systems.
+// On PowerPC it is larger, to cover three more reserved words:
+// the compiler word, the link editor word, and the TOC save word.
+const MinFrameSize = _MinFrameSize
+
+// StackAlign is the required alignment of the SP register.
+// The stack must be at least word aligned, but some architectures require more.
+const StackAlign = _StackAlign
diff --git a/contrib/go/_std_1.18/src/internal/goarch/goarch_amd64.go b/contrib/go/_std_1.19/src/internal/goarch/goarch_amd64.go
index 911e3e7242..911e3e7242 100644
--- a/contrib/go/_std_1.18/src/internal/goarch/goarch_amd64.go
+++ b/contrib/go/_std_1.19/src/internal/goarch/goarch_amd64.go
diff --git a/contrib/go/_std_1.18/src/internal/goarch/zgoarch_amd64.go b/contrib/go/_std_1.19/src/internal/goarch/zgoarch_amd64.go
index 7926392b77..7926392b77 100644
--- a/contrib/go/_std_1.18/src/internal/goarch/zgoarch_amd64.go
+++ b/contrib/go/_std_1.19/src/internal/goarch/zgoarch_amd64.go
diff --git a/contrib/go/_std_1.18/src/internal/godebug/godebug.go b/contrib/go/_std_1.19/src/internal/godebug/godebug.go
index ac434e5fd8..ac434e5fd8 100644
--- a/contrib/go/_std_1.18/src/internal/godebug/godebug.go
+++ b/contrib/go/_std_1.19/src/internal/godebug/godebug.go
diff --git a/contrib/go/_std_1.19/src/internal/goexperiment/exp_boringcrypto_off.go b/contrib/go/_std_1.19/src/internal/goexperiment/exp_boringcrypto_off.go
new file mode 100644
index 0000000000..020c75bd53
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/goexperiment/exp_boringcrypto_off.go
@@ -0,0 +1,9 @@
+// Code generated by mkconsts.go. DO NOT EDIT.
+
+//go:build !goexperiment.boringcrypto
+// +build !goexperiment.boringcrypto
+
+package goexperiment
+
+const BoringCrypto = false
+const BoringCryptoInt = 0
diff --git a/contrib/go/_std_1.18/src/internal/goexperiment/exp_fieldtrack_off.go b/contrib/go/_std_1.19/src/internal/goexperiment/exp_fieldtrack_off.go
index e5e132660e..e5e132660e 100644
--- a/contrib/go/_std_1.18/src/internal/goexperiment/exp_fieldtrack_off.go
+++ b/contrib/go/_std_1.19/src/internal/goexperiment/exp_fieldtrack_off.go
diff --git a/contrib/go/_std_1.18/src/internal/goexperiment/exp_heapminimum512kib_off.go b/contrib/go/_std_1.19/src/internal/goexperiment/exp_heapminimum512kib_off.go
index 09da431b40..09da431b40 100644
--- a/contrib/go/_std_1.18/src/internal/goexperiment/exp_heapminimum512kib_off.go
+++ b/contrib/go/_std_1.19/src/internal/goexperiment/exp_heapminimum512kib_off.go
diff --git a/contrib/go/_std_1.18/src/internal/goexperiment/exp_preemptibleloops_off.go b/contrib/go/_std_1.19/src/internal/goexperiment/exp_preemptibleloops_off.go
index 7a26088e80..7a26088e80 100644
--- a/contrib/go/_std_1.18/src/internal/goexperiment/exp_preemptibleloops_off.go
+++ b/contrib/go/_std_1.19/src/internal/goexperiment/exp_preemptibleloops_off.go
diff --git a/contrib/go/_std_1.18/src/internal/goexperiment/exp_regabiargs_on.go b/contrib/go/_std_1.19/src/internal/goexperiment/exp_regabiargs_on.go
index 9b26f3c9cb..9b26f3c9cb 100644
--- a/contrib/go/_std_1.18/src/internal/goexperiment/exp_regabiargs_on.go
+++ b/contrib/go/_std_1.19/src/internal/goexperiment/exp_regabiargs_on.go
diff --git a/contrib/go/_std_1.18/src/internal/goexperiment/exp_regabiwrappers_on.go b/contrib/go/_std_1.19/src/internal/goexperiment/exp_regabiwrappers_on.go
index 11ffffbbff..11ffffbbff 100644
--- a/contrib/go/_std_1.18/src/internal/goexperiment/exp_regabiwrappers_on.go
+++ b/contrib/go/_std_1.19/src/internal/goexperiment/exp_regabiwrappers_on.go
diff --git a/contrib/go/_std_1.18/src/internal/goexperiment/exp_staticlockranking_off.go b/contrib/go/_std_1.19/src/internal/goexperiment/exp_staticlockranking_off.go
index 3d546c04b4..3d546c04b4 100644
--- a/contrib/go/_std_1.18/src/internal/goexperiment/exp_staticlockranking_off.go
+++ b/contrib/go/_std_1.19/src/internal/goexperiment/exp_staticlockranking_off.go
diff --git a/contrib/go/_std_1.18/src/internal/goexperiment/exp_unified_off.go b/contrib/go/_std_1.19/src/internal/goexperiment/exp_unified_off.go
index 4c16fd8562..4c16fd8562 100644
--- a/contrib/go/_std_1.18/src/internal/goexperiment/exp_unified_off.go
+++ b/contrib/go/_std_1.19/src/internal/goexperiment/exp_unified_off.go
diff --git a/contrib/go/_std_1.19/src/internal/goexperiment/flags.go b/contrib/go/_std_1.19/src/internal/goexperiment/flags.go
new file mode 100644
index 0000000000..20d9c2da5d
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/goexperiment/flags.go
@@ -0,0 +1,89 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package goexperiment implements support for toolchain experiments.
+//
+// Toolchain experiments are controlled by the GOEXPERIMENT
+// environment variable. GOEXPERIMENT is a comma-separated list of
+// experiment names. GOEXPERIMENT can be set at make.bash time, which
+// sets the default experiments for binaries built with the tool
+// chain; or it can be set at build time. GOEXPERIMENT can also be set
+// to "none", which disables any experiments that were enabled at
+// make.bash time.
+//
+// Experiments are exposed to the build in the following ways:
+//
+// - Build tag goexperiment.x is set if experiment x (lower case) is
+// enabled.
+//
+// - For each experiment x (in camel case), this package contains a
+// boolean constant x and an integer constant xInt.
+//
+// - In runtime assembly, the macro GOEXPERIMENT_x is defined if
+// experiment x (lower case) is enabled.
+//
+// In the toolchain, the set of experiments enabled for the current
+// build should be accessed via objabi.Experiment.
+//
+// The set of experiments is included in the output of runtime.Version()
+// and "go version <binary>" if it differs from the default experiments.
+//
+// For the set of experiments supported by the current toolchain, see
+// "go doc goexperiment.Flags".
+//
+// Note that this package defines the set of experiments (in Flags)
+// and records the experiments that were enabled when the package
+// was compiled (as boolean and integer constants).
+//
+// Note especially that this package does not itself change behavior
+// at run time based on the GOEXPERIMENT variable.
+// The code used in builds to interpret the GOEXPERIMENT variable
+// is in the separate package internal/buildcfg.
+package goexperiment
+
+//go:generate go run mkconsts.go
+
+// Flags is the set of experiments that can be enabled or disabled in
+// the current toolchain.
+//
+// When specified in the GOEXPERIMENT environment variable or as build
+// tags, experiments use the strings.ToLower of their field name.
+//
+// For the baseline experimental configuration, see
+// objabi.experimentBaseline.
+//
+// If you change this struct definition, run "go generate".
+type Flags struct {
+	FieldTrack        bool
+	PreemptibleLoops  bool
+	StaticLockRanking bool
+	BoringCrypto      bool
+
+	// Unified enables the compiler's unified IR construction
+	// experiment.
+	Unified bool
+
+	// Regabi is split into several sub-experiments that can be
+	// enabled individually. Not all combinations work.
+	// The "regabi" GOEXPERIMENT is an alias for all "working"
+	// subexperiments.
+
+	// RegabiWrappers enables ABI wrappers for calling between
+	// ABI0 and ABIInternal functions. Without this, the ABIs are
+	// assumed to be identical so cross-ABI calls are direct.
+	RegabiWrappers bool
+	// RegabiArgs enables register arguments/results in all
+	// compiled Go functions.
+	//
+	// Requires wrappers (to do ABI translation), and reflect (so
+	// reflection calls use registers).
+	RegabiArgs bool
+
+	// HeapMinimum512KiB reduces the minimum heap size to 512 KiB.
+	//
+	// This was originally reduced as part of PacerRedesign, but
+	// has been broken out to its own experiment that is disabled
+	// by default.
+	HeapMinimum512KiB bool
+}
diff --git a/contrib/go/_std_1.19/src/internal/goos/goos.go b/contrib/go/_std_1.19/src/internal/goos/goos.go
new file mode 100644
index 0000000000..02dc9688cb
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/goos/goos.go
@@ -0,0 +1,13 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// package goos contains GOOS-specific constants.
+package goos
+
+// The next line makes 'go generate' write the zgoos*.go files with
+// per-OS information, including constants named Is$GOOS for every
+// known GOOS. The constant is 1 on the current system, 0 otherwise;
+// multiplying by them is useful for defining GOOS-specific constants.
+//
+//go:generate go run gengoos.go
diff --git a/contrib/go/_std_1.18/src/internal/goos/zgoos_darwin.go b/contrib/go/_std_1.19/src/internal/goos/zgoos_darwin.go
index decdd49642..decdd49642 100644
--- a/contrib/go/_std_1.18/src/internal/goos/zgoos_darwin.go
+++ b/contrib/go/_std_1.19/src/internal/goos/zgoos_darwin.go
diff --git a/contrib/go/_std_1.18/src/internal/goos/zgoos_linux.go b/contrib/go/_std_1.19/src/internal/goos/zgoos_linux.go
index cb9d6e8afa..cb9d6e8afa 100644
--- a/contrib/go/_std_1.18/src/internal/goos/zgoos_linux.go
+++ b/contrib/go/_std_1.19/src/internal/goos/zgoos_linux.go
diff --git a/contrib/go/_std_1.19/src/internal/intern/intern.go b/contrib/go/_std_1.19/src/internal/intern/intern.go
new file mode 100644
index 0000000000..c7639b4668
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/intern/intern.go
@@ -0,0 +1,179 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package intern lets you make smaller comparable values by boxing
+// a larger comparable value (such as a 16 byte string header) down
+// into a globally unique 8 byte pointer.
+//
+// The globally unique pointers are garbage collected with weak
+// references and finalizers. This package hides that.
+package intern
+
+import (
+	"internal/godebug"
+	"runtime"
+	"sync"
+	"unsafe"
+)
+
+// A Value pointer is the handle to an underlying comparable value.
+// See func Get for how Value pointers may be used.
+type Value struct {
+	_      [0]func() // prevent people from accidentally using value type as comparable
+	cmpVal any
+	// resurrected is guarded by mu (for all instances of Value).
+	// It is set true whenever v is synthesized from a uintptr.
+	resurrected bool
+}
+
+// Get returns the comparable value passed to the Get func
+// that returned v.
+func (v *Value) Get() any { return v.cmpVal }
+
+// key is a key in our global value map.
+// It contains type-specialized fields to avoid allocations
+// when converting common types to empty interfaces.
+type key struct {
+	s      string
+	cmpVal any
+	// isString reports whether key contains a string.
+	// Without it, the zero value of key is ambiguous.
+	isString bool
+}
+
+// keyFor returns a key to use with cmpVal.
+func keyFor(cmpVal any) key {
+	if s, ok := cmpVal.(string); ok {
+		return key{s: s, isString: true}
+	}
+	return key{cmpVal: cmpVal}
+}
+
+// Value returns a *Value built from k.
+func (k key) Value() *Value {
+	if k.isString {
+		return &Value{cmpVal: k.s}
+	}
+	return &Value{cmpVal: k.cmpVal}
+}
+
+var (
+	// mu guards valMap, a weakref map of *Value by underlying value.
+	// It also guards the resurrected field of all *Values.
+	mu      sync.Mutex
+	valMap  = map[key]uintptr{} // to uintptr(*Value)
+	valSafe = safeMap()         // non-nil in safe+leaky mode
+)
+
+// safeMap returns a non-nil map if we're in safe-but-leaky mode,
+// as controlled by GODEBUG=intern=leaky
+func safeMap() map[key]*Value {
+	if godebug.Get("intern") == "leaky" {
+		return map[key]*Value{}
+	}
+	return nil
+}
+
+// Get returns a pointer representing the comparable value cmpVal.
+//
+// The returned pointer will be the same for Get(v) and Get(v2)
+// if and only if v == v2, and can be used as a map key.
+func Get(cmpVal any) *Value {
+	return get(keyFor(cmpVal))
+}
+
+// GetByString is identical to Get, except that it is specialized for strings.
+// This avoids an allocation from putting a string into an interface{}
+// to pass as an argument to Get.
+func GetByString(s string) *Value {
+	return get(key{s: s, isString: true})
+}
+
+// We play unsafe games that violate Go's rules (and assume a non-moving
+// collector). So we quiet Go here.
+// See the comment below Get for more implementation details.
+//
+//go:nocheckptr
+func get(k key) *Value {
+	mu.Lock()
+	defer mu.Unlock()
+
+	var v *Value
+	if valSafe != nil {
+		v = valSafe[k]
+	} else if addr, ok := valMap[k]; ok {
+		v = (*Value)(unsafe.Pointer(addr))
+		v.resurrected = true
+	}
+	if v != nil {
+		return v
+	}
+	v = k.Value()
+	if valSafe != nil {
+		valSafe[k] = v
+	} else {
+		// SetFinalizer before uintptr conversion (theoretical concern;
+		// see https://github.com/go4org/intern/issues/13)
+		runtime.SetFinalizer(v, finalize)
+		valMap[k] = uintptr(unsafe.Pointer(v))
+	}
+	return v
+}
+
+func finalize(v *Value) {
+	mu.Lock()
+	defer mu.Unlock()
+	if v.resurrected {
+		// We lost the race. Somebody resurrected it while we
+		// were about to finalize it. Try again next round.
+		v.resurrected = false
+		runtime.SetFinalizer(v, finalize)
+		return
+	}
+	delete(valMap, keyFor(v.cmpVal))
+}
+
+// Interning is simple if you don't require that unused values be
+// garbage collectable. But we do require that; we don't want to be
+// DOS vector. We do this by using a uintptr to hide the pointer from
+// the garbage collector, and using a finalizer to eliminate the
+// pointer when no other code is using it.
+//
+// The obvious implementation of this is to use a
+// map[interface{}]uintptr-of-*interface{}, and set up a finalizer to
+// delete from the map. Unfortunately, this is racy. Because pointers
+// are being created in violation of Go's unsafety rules, it's
+// possible to create a pointer to a value concurrently with the GC
+// concluding that the value can be collected. There are other races
+// that break the equality invariant as well, but the use-after-free
+// will cause a runtime crash.
+//
+// To make this work, the finalizer needs to know that no references
+// have been unsafely created since the finalizer was set up. To do
+// this, values carry a "resurrected" sentinel, which gets set
+// whenever a pointer is unsafely created. If the finalizer encounters
+// the sentinel, it clears the sentinel and delays collection for one
+// additional GC cycle, by re-installing itself as finalizer. This
+// ensures that the unsafely created pointer is visible to the GC, and
+// will correctly prevent collection.
+//
+// This technique does mean that interned values that get reused take
+// at least 3 GC cycles to fully collect (1 to clear the sentinel, 1
+// to clean up the unsafe map, 1 to be actually deleted).
+//
+// @ianlancetaylor commented in
+// https://github.com/golang/go/issues/41303#issuecomment-717401656
+// that it is possible to implement weak references in terms of
+// finalizers without unsafe. Unfortunately, the approach he outlined
+// does not work here, for two reasons. First, there is no way to
+// construct a strong pointer out of a weak pointer; our map stores
+// weak pointers, but we must return strong pointers to callers.
+// Second, and more fundamentally, we must return not just _a_ strong
+// pointer to callers, but _the same_ strong pointer to callers. In
+// order to return _the same_ strong pointer to callers, we must track
+// it, which is exactly what we cannot do with strong pointers.
+//
+// See https://github.com/inetaf/netaddr/issues/53 for more
+// discussion, and https://github.com/go4org/intern/issues/2 for an
+// illustration of the subtleties at play.
diff --git a/contrib/go/_std_1.18/src/internal/itoa/itoa.go b/contrib/go/_std_1.19/src/internal/itoa/itoa.go
index c6062d9fe1..c6062d9fe1 100644
--- a/contrib/go/_std_1.18/src/internal/itoa/itoa.go
+++ b/contrib/go/_std_1.19/src/internal/itoa/itoa.go
diff --git a/contrib/go/_std_1.19/src/internal/nettrace/nettrace.go b/contrib/go/_std_1.19/src/internal/nettrace/nettrace.go
new file mode 100644
index 0000000000..0a2bf925e9
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/nettrace/nettrace.go
@@ -0,0 +1,46 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package nettrace contains internal hooks for tracing activity in
+// the net package. This package is purely internal for use by the
+// net/http/httptrace package and has no stable API exposed to end
+// users.
+package nettrace
+
+// TraceKey is a context.Context Value key. Its associated value should
+// be a *Trace struct.
+type TraceKey struct{}
+
+// LookupIPAltResolverKey is a context.Context Value key used by tests to
+// specify an alternate resolver func.
+// It is not exposed to outsider users. (But see issue 12503)
+// The value should be the same type as lookupIP:
+//
+//	func lookupIP(ctx context.Context, host string) ([]IPAddr, error)
+type LookupIPAltResolverKey struct{}
+
+// Trace contains a set of hooks for tracing events within
+// the net package. Any specific hook may be nil.
+type Trace struct {
+	// DNSStart is called with the hostname of a DNS lookup
+	// before it begins.
+	DNSStart func(name string)
+
+	// DNSDone is called after a DNS lookup completes (or fails).
+	// The coalesced parameter is whether singleflight de-duped
+	// the call. The addrs are of type net.IPAddr but can't
+	// actually be for circular dependency reasons.
+	DNSDone func(netIPs []any, coalesced bool, err error)
+
+	// ConnectStart is called before a Dial, excluding Dials made
+	// during DNS lookups. In the case of DualStack (Happy Eyeballs)
+	// dialing, this may be called multiple times, from multiple
+	// goroutines.
+	ConnectStart func(network, addr string)
+
+	// ConnectStart is called after a Dial with the results, excluding
+	// Dials made during DNS lookups. It may also be called multiple
+	// times, like ConnectStart.
+	ConnectDone func(network, addr string, err error)
+}
diff --git a/contrib/go/_std_1.18/src/internal/oserror/errors.go b/contrib/go/_std_1.19/src/internal/oserror/errors.go
index 28a1ab32d3..28a1ab32d3 100644
--- a/contrib/go/_std_1.18/src/internal/oserror/errors.go
+++ b/contrib/go/_std_1.19/src/internal/oserror/errors.go
diff --git a/contrib/go/_std_1.18/src/internal/poll/copy_file_range_linux.go b/contrib/go/_std_1.19/src/internal/poll/copy_file_range_linux.go
index 5b9e5d4020..5b9e5d4020 100644
--- a/contrib/go/_std_1.18/src/internal/poll/copy_file_range_linux.go
+++ b/contrib/go/_std_1.19/src/internal/poll/copy_file_range_linux.go
diff --git a/contrib/go/_std_1.19/src/internal/poll/errno_unix.go b/contrib/go/_std_1.19/src/internal/poll/errno_unix.go
new file mode 100644
index 0000000000..8eed93a31c
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/poll/errno_unix.go
@@ -0,0 +1,33 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix
+
+package poll
+
+import "syscall"
+
+// Do the interface allocations only once for common
+// Errno values.
+var (
+	errEAGAIN error = syscall.EAGAIN
+	errEINVAL error = syscall.EINVAL
+	errENOENT error = syscall.ENOENT
+)
+
+// errnoErr returns common boxed Errno values, to prevent
+// allocations at runtime.
+func errnoErr(e syscall.Errno) error {
+	switch e {
+	case 0:
+		return nil
+	case syscall.EAGAIN:
+		return errEAGAIN
+	case syscall.EINVAL:
+		return errEINVAL
+	case syscall.ENOENT:
+		return errENOENT
+	}
+	return e
+}
diff --git a/contrib/go/_std_1.19/src/internal/poll/fcntl_libc.go b/contrib/go/_std_1.19/src/internal/poll/fcntl_libc.go
new file mode 100644
index 0000000000..13614dc3e8
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/poll/fcntl_libc.go
@@ -0,0 +1,14 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build aix || darwin || solaris
+
+package poll
+
+import _ "unsafe" // for go:linkname
+
+// Implemented in the syscall package.
+//
+//go:linkname fcntl syscall.fcntl
+func fcntl(fd int, cmd int, arg int) (int, error)
diff --git a/contrib/go/_std_1.18/src/internal/poll/fcntl_syscall.go b/contrib/go/_std_1.19/src/internal/poll/fcntl_syscall.go
index accff5e043..accff5e043 100644
--- a/contrib/go/_std_1.18/src/internal/poll/fcntl_syscall.go
+++ b/contrib/go/_std_1.19/src/internal/poll/fcntl_syscall.go
diff --git a/contrib/go/_std_1.19/src/internal/poll/fd.go b/contrib/go/_std_1.19/src/internal/poll/fd.go
new file mode 100644
index 0000000000..ef61d0cb3f
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/poll/fd.go
@@ -0,0 +1,83 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package poll supports non-blocking I/O on file descriptors with polling.
+// This supports I/O operations that block only a goroutine, not a thread.
+// This is used by the net and os packages.
+// It uses a poller built into the runtime, with support from the
+// runtime scheduler.
+package poll
+
+import (
+	"errors"
+)
+
+// errNetClosing is the type of the variable ErrNetClosing.
+// This is used to implement the net.Error interface.
+type errNetClosing struct{}
+
+// Error returns the error message for ErrNetClosing.
+// Keep this string consistent because of issue #4373:
+// since historically programs have not been able to detect
+// this error, they look for the string.
+func (e errNetClosing) Error() string { return "use of closed network connection" }
+
+func (e errNetClosing) Timeout() bool   { return false }
+func (e errNetClosing) Temporary() bool { return false }
+
+// ErrNetClosing is returned when a network descriptor is used after
+// it has been closed.
+var ErrNetClosing = errNetClosing{}
+
+// ErrFileClosing is returned when a file descriptor is used after it
+// has been closed.
+var ErrFileClosing = errors.New("use of closed file")
+
+// ErrNoDeadline is returned when a request is made to set a deadline
+// on a file type that does not use the poller.
+var ErrNoDeadline = errors.New("file type does not support deadline")
+
+// Return the appropriate closing error based on isFile.
+func errClosing(isFile bool) error {
+	if isFile {
+		return ErrFileClosing
+	}
+	return ErrNetClosing
+}
+
+// ErrDeadlineExceeded is returned for an expired deadline.
+// This is exported by the os package as os.ErrDeadlineExceeded.
+var ErrDeadlineExceeded error = &DeadlineExceededError{}
+
+// DeadlineExceededError is returned for an expired deadline.
+type DeadlineExceededError struct{}
+
+// Implement the net.Error interface.
+// The string is "i/o timeout" because that is what was returned
+// by earlier Go versions. Changing it may break programs that
+// match on error strings.
+func (e *DeadlineExceededError) Error() string   { return "i/o timeout" }
+func (e *DeadlineExceededError) Timeout() bool   { return true }
+func (e *DeadlineExceededError) Temporary() bool { return true }
+
+// ErrNotPollable is returned when the file or socket is not suitable
+// for event notification.
+var ErrNotPollable = errors.New("not pollable")
+
+// consume removes data from a slice of byte slices, for writev.
+func consume(v *[][]byte, n int64) {
+	for len(*v) > 0 {
+		ln0 := int64(len((*v)[0]))
+		if ln0 > n {
+			(*v)[0] = (*v)[0][n:]
+			return
+		}
+		n -= ln0
+		(*v)[0] = nil
+		*v = (*v)[1:]
+	}
+}
+
+// TestHookDidWritev is a hook for testing writev.
+var TestHookDidWritev = func(wrote int) {}
diff --git a/contrib/go/_std_1.18/src/internal/poll/fd_fsync_darwin.go b/contrib/go/_std_1.19/src/internal/poll/fd_fsync_darwin.go
index 48e7596922..48e7596922 100644
--- a/contrib/go/_std_1.18/src/internal/poll/fd_fsync_darwin.go
+++ b/contrib/go/_std_1.19/src/internal/poll/fd_fsync_darwin.go
diff --git a/contrib/go/_std_1.18/src/internal/poll/fd_fsync_posix.go b/contrib/go/_std_1.19/src/internal/poll/fd_fsync_posix.go
index 6f17019e73..6f17019e73 100644
--- a/contrib/go/_std_1.18/src/internal/poll/fd_fsync_posix.go
+++ b/contrib/go/_std_1.19/src/internal/poll/fd_fsync_posix.go
diff --git a/contrib/go/_std_1.18/src/internal/poll/fd_mutex.go b/contrib/go/_std_1.19/src/internal/poll/fd_mutex.go
index 0a8ee6f0d4..0a8ee6f0d4 100644
--- a/contrib/go/_std_1.18/src/internal/poll/fd_mutex.go
+++ b/contrib/go/_std_1.19/src/internal/poll/fd_mutex.go
diff --git a/contrib/go/_std_1.19/src/internal/poll/fd_opendir_darwin.go b/contrib/go/_std_1.19/src/internal/poll/fd_opendir_darwin.go
new file mode 100644
index 0000000000..3ae2dc8448
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/poll/fd_opendir_darwin.go
@@ -0,0 +1,39 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package poll
+
+import (
+	"syscall"
+	_ "unsafe" // for go:linkname
+)
+
+// OpenDir returns a pointer to a DIR structure suitable for
+// ReadDir. In case of an error, the name of the failed
+// syscall is returned along with a syscall.Errno.
+func (fd *FD) OpenDir() (uintptr, string, error) {
+	// fdopendir(3) takes control of the file descriptor,
+	// so use a dup.
+	fd2, call, err := fd.Dup()
+	if err != nil {
+		return 0, call, err
+	}
+	var dir uintptr
+	for {
+		dir, err = fdopendir(fd2)
+		if err != syscall.EINTR {
+			break
+		}
+	}
+	if err != nil {
+		syscall.Close(fd2)
+		return 0, "fdopendir", err
+	}
+	return dir, "", nil
+}
+
+// Implemented in syscall/syscall_darwin.go.
+//
+//go:linkname fdopendir syscall.fdopendir
+func fdopendir(fd int) (dir uintptr, err error)
diff --git a/contrib/go/_std_1.19/src/internal/poll/fd_poll_runtime.go b/contrib/go/_std_1.19/src/internal/poll/fd_poll_runtime.go
new file mode 100644
index 0000000000..4d3cc78405
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/poll/fd_poll_runtime.go
@@ -0,0 +1,169 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || windows
+
+package poll
+
+import (
+	"errors"
+	"sync"
+	"syscall"
+	"time"
+	_ "unsafe" // for go:linkname
+)
+
+// runtimeNano returns the current value of the runtime clock in nanoseconds.
+//
+//go:linkname runtimeNano runtime.nanotime
+func runtimeNano() int64
+
+func runtime_pollServerInit()
+func runtime_pollOpen(fd uintptr) (uintptr, int)
+func runtime_pollClose(ctx uintptr)
+func runtime_pollWait(ctx uintptr, mode int) int
+func runtime_pollWaitCanceled(ctx uintptr, mode int) int
+func runtime_pollReset(ctx uintptr, mode int) int
+func runtime_pollSetDeadline(ctx uintptr, d int64, mode int)
+func runtime_pollUnblock(ctx uintptr)
+func runtime_isPollServerDescriptor(fd uintptr) bool
+
+type pollDesc struct {
+	runtimeCtx uintptr
+}
+
+var serverInit sync.Once
+
+func (pd *pollDesc) init(fd *FD) error {
+	serverInit.Do(runtime_pollServerInit)
+	ctx, errno := runtime_pollOpen(uintptr(fd.Sysfd))
+	if errno != 0 {
+		return errnoErr(syscall.Errno(errno))
+	}
+	pd.runtimeCtx = ctx
+	return nil
+}
+
+func (pd *pollDesc) close() {
+	if pd.runtimeCtx == 0 {
+		return
+	}
+	runtime_pollClose(pd.runtimeCtx)
+	pd.runtimeCtx = 0
+}
+
+// Evict evicts fd from the pending list, unblocking any I/O running on fd.
+func (pd *pollDesc) evict() {
+	if pd.runtimeCtx == 0 {
+		return
+	}
+	runtime_pollUnblock(pd.runtimeCtx)
+}
+
+func (pd *pollDesc) prepare(mode int, isFile bool) error {
+	if pd.runtimeCtx == 0 {
+		return nil
+	}
+	res := runtime_pollReset(pd.runtimeCtx, mode)
+	return convertErr(res, isFile)
+}
+
+func (pd *pollDesc) prepareRead(isFile bool) error {
+	return pd.prepare('r', isFile)
+}
+
+func (pd *pollDesc) prepareWrite(isFile bool) error {
+	return pd.prepare('w', isFile)
+}
+
+func (pd *pollDesc) wait(mode int, isFile bool) error {
+	if pd.runtimeCtx == 0 {
+		return errors.New("waiting for unsupported file type")
+	}
+	res := runtime_pollWait(pd.runtimeCtx, mode)
+	return convertErr(res, isFile)
+}
+
+func (pd *pollDesc) waitRead(isFile bool) error {
+	return pd.wait('r', isFile)
+}
+
+func (pd *pollDesc) waitWrite(isFile bool) error {
+	return pd.wait('w', isFile)
+}
+
+func (pd *pollDesc) waitCanceled(mode int) {
+	if pd.runtimeCtx == 0 {
+		return
+	}
+	runtime_pollWaitCanceled(pd.runtimeCtx, mode)
+}
+
+func (pd *pollDesc) pollable() bool {
+	return pd.runtimeCtx != 0
+}
+
+// Error values returned by runtime_pollReset and runtime_pollWait.
+// These must match the values in runtime/netpoll.go.
+const (
+	pollNoError        = 0
+	pollErrClosing     = 1
+	pollErrTimeout     = 2
+	pollErrNotPollable = 3
+)
+
+func convertErr(res int, isFile bool) error {
+	switch res {
+	case pollNoError:
+		return nil
+	case pollErrClosing:
+		return errClosing(isFile)
+	case pollErrTimeout:
+		return ErrDeadlineExceeded
+	case pollErrNotPollable:
+		return ErrNotPollable
+	}
+	println("unreachable: ", res)
+	panic("unreachable")
+}
+
+// SetDeadline sets the read and write deadlines associated with fd.
+func (fd *FD) SetDeadline(t time.Time) error {
+	return setDeadlineImpl(fd, t, 'r'+'w')
+}
+
+// SetReadDeadline sets the read deadline associated with fd.
+func (fd *FD) SetReadDeadline(t time.Time) error {
+	return setDeadlineImpl(fd, t, 'r')
+}
+
+// SetWriteDeadline sets the write deadline associated with fd.
+func (fd *FD) SetWriteDeadline(t time.Time) error {
+	return setDeadlineImpl(fd, t, 'w')
+}
+
+func setDeadlineImpl(fd *FD, t time.Time, mode int) error {
+	var d int64
+	if !t.IsZero() {
+		d = int64(time.Until(t))
+		if d == 0 {
+			d = -1 // don't confuse deadline right now with no deadline
+		}
+	}
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	if fd.pd.runtimeCtx == 0 {
+		return ErrNoDeadline
+	}
+	runtime_pollSetDeadline(fd.pd.runtimeCtx, d, mode)
+	return nil
+}
+
+// IsPollDescriptor reports whether fd is the descriptor being used by the poller.
+// This is only used for testing.
+func IsPollDescriptor(fd uintptr) bool {
+	return runtime_isPollServerDescriptor(fd)
+}
diff --git a/contrib/go/_std_1.19/src/internal/poll/fd_posix.go b/contrib/go/_std_1.19/src/internal/poll/fd_posix.go
new file mode 100644
index 0000000000..778fe1e5c1
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/poll/fd_posix.go
@@ -0,0 +1,79 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm) || windows
+
+package poll
+
+import (
+	"io"
+	"syscall"
+)
+
+// eofError returns io.EOF when fd is available for reading end of
+// file.
+func (fd *FD) eofError(n int, err error) error {
+	if n == 0 && err == nil && fd.ZeroReadIsEOF {
+		return io.EOF
+	}
+	return err
+}
+
+// Shutdown wraps syscall.Shutdown.
+func (fd *FD) Shutdown(how int) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.Shutdown(fd.Sysfd, how)
+}
+
+// Fchown wraps syscall.Fchown.
+func (fd *FD) Fchown(uid, gid int) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return ignoringEINTR(func() error {
+		return syscall.Fchown(fd.Sysfd, uid, gid)
+	})
+}
+
+// Ftruncate wraps syscall.Ftruncate.
+func (fd *FD) Ftruncate(size int64) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return ignoringEINTR(func() error {
+		return syscall.Ftruncate(fd.Sysfd, size)
+	})
+}
+
+// RawControl invokes the user-defined function f for a non-IO
+// operation.
+func (fd *FD) RawControl(f func(uintptr)) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	f(uintptr(fd.Sysfd))
+	return nil
+}
+
+// ignoringEINTR makes a function call and repeats it if it returns
+// an EINTR error. This appears to be required even though we install all
+// signal handlers with SA_RESTART: see #22838, #38033, #38836, #40846.
+// Also #20400 and #36644 are issues in which a signal handler is
+// installed without setting SA_RESTART. None of these are the common case,
+// but there are enough of them that it seems that we can't avoid
+// an EINTR loop.
+func ignoringEINTR(fn func() error) error {
+	for {
+		err := fn()
+		if err != syscall.EINTR {
+			return err
+		}
+	}
+}
diff --git a/contrib/go/_std_1.19/src/internal/poll/fd_unix.go b/contrib/go/_std_1.19/src/internal/poll/fd_unix.go
new file mode 100644
index 0000000000..2786064d9f
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/poll/fd_unix.go
@@ -0,0 +1,799 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm)
+
+package poll
+
+import (
+	"internal/syscall/unix"
+	"io"
+	"sync/atomic"
+	"syscall"
+)
+
+// FD is a file descriptor. The net and os packages use this type as a
+// field of a larger type representing a network connection or OS file.
+type FD struct {
+	// Lock sysfd and serialize access to Read and Write methods.
+	fdmu fdMutex
+
+	// System file descriptor. Immutable until Close.
+	Sysfd int
+
+	// I/O poller.
+	pd pollDesc
+
+	// Writev cache.
+	iovecs *[]syscall.Iovec
+
+	// Semaphore signaled when file is closed.
+	csema uint32
+
+	// Non-zero if this file has been set to blocking mode.
+	isBlocking uint32
+
+	// Whether this is a streaming descriptor, as opposed to a
+	// packet-based descriptor like a UDP socket. Immutable.
+	IsStream bool
+
+	// Whether a zero byte read indicates EOF. This is false for a
+	// message based socket connection.
+	ZeroReadIsEOF bool
+
+	// Whether this is a file rather than a network socket.
+	isFile bool
+}
+
+// Init initializes the FD. The Sysfd field should already be set.
+// This can be called multiple times on a single FD.
+// The net argument is a network name from the net package (e.g., "tcp"),
+// or "file".
+// Set pollable to true if fd should be managed by runtime netpoll.
+func (fd *FD) Init(net string, pollable bool) error {
+	// We don't actually care about the various network types.
+	if net == "file" {
+		fd.isFile = true
+	}
+	if !pollable {
+		fd.isBlocking = 1
+		return nil
+	}
+	err := fd.pd.init(fd)
+	if err != nil {
+		// If we could not initialize the runtime poller,
+		// assume we are using blocking mode.
+		fd.isBlocking = 1
+	}
+	return err
+}
+
+// Destroy closes the file descriptor. This is called when there are
+// no remaining references.
+func (fd *FD) destroy() error {
+	// Poller may want to unregister fd in readiness notification mechanism,
+	// so this must be executed before CloseFunc.
+	fd.pd.close()
+
+	// We don't use ignoringEINTR here because POSIX does not define
+	// whether the descriptor is closed if close returns EINTR.
+	// If the descriptor is indeed closed, using a loop would race
+	// with some other goroutine opening a new descriptor.
+	// (The Linux kernel guarantees that it is closed on an EINTR error.)
+	err := CloseFunc(fd.Sysfd)
+
+	fd.Sysfd = -1
+	runtime_Semrelease(&fd.csema)
+	return err
+}
+
+// Close closes the FD. The underlying file descriptor is closed by the
+// destroy method when there are no remaining references.
+func (fd *FD) Close() error {
+	if !fd.fdmu.increfAndClose() {
+		return errClosing(fd.isFile)
+	}
+
+	// Unblock any I/O.  Once it all unblocks and returns,
+	// so that it cannot be referring to fd.sysfd anymore,
+	// the final decref will close fd.sysfd. This should happen
+	// fairly quickly, since all the I/O is non-blocking, and any
+	// attempts to block in the pollDesc will return errClosing(fd.isFile).
+	fd.pd.evict()
+
+	// The call to decref will call destroy if there are no other
+	// references.
+	err := fd.decref()
+
+	// Wait until the descriptor is closed. If this was the only
+	// reference, it is already closed. Only wait if the file has
+	// not been set to blocking mode, as otherwise any current I/O
+	// may be blocking, and that would block the Close.
+	// No need for an atomic read of isBlocking, increfAndClose means
+	// we have exclusive access to fd.
+	if fd.isBlocking == 0 {
+		runtime_Semacquire(&fd.csema)
+	}
+
+	return err
+}
+
+// SetBlocking puts the file into blocking mode.
+func (fd *FD) SetBlocking() error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	// Atomic store so that concurrent calls to SetBlocking
+	// do not cause a race condition. isBlocking only ever goes
+	// from 0 to 1 so there is no real race here.
+	atomic.StoreUint32(&fd.isBlocking, 1)
+	return syscall.SetNonblock(fd.Sysfd, false)
+}
+
+// Darwin and FreeBSD can't read or write 2GB+ files at a time,
+// even on 64-bit systems.
+// The same is true of socket implementations on many systems.
+// See golang.org/issue/7812 and golang.org/issue/16266.
+// Use 1GB instead of, say, 2GB-1, to keep subsequent reads aligned.
+const maxRW = 1 << 30
+
+// Read implements io.Reader.
+func (fd *FD) Read(p []byte) (int, error) {
+	if err := fd.readLock(); err != nil {
+		return 0, err
+	}
+	defer fd.readUnlock()
+	if len(p) == 0 {
+		// If the caller wanted a zero byte read, return immediately
+		// without trying (but after acquiring the readLock).
+		// Otherwise syscall.Read returns 0, nil which looks like
+		// io.EOF.
+		// TODO(bradfitz): make it wait for readability? (Issue 15735)
+		return 0, nil
+	}
+	if err := fd.pd.prepareRead(fd.isFile); err != nil {
+		return 0, err
+	}
+	if fd.IsStream && len(p) > maxRW {
+		p = p[:maxRW]
+	}
+	for {
+		n, err := ignoringEINTRIO(syscall.Read, fd.Sysfd, p)
+		if err != nil {
+			n = 0
+			if err == syscall.EAGAIN && fd.pd.pollable() {
+				if err = fd.pd.waitRead(fd.isFile); err == nil {
+					continue
+				}
+			}
+		}
+		err = fd.eofError(n, err)
+		return n, err
+	}
+}
+
+// Pread wraps the pread system call.
+func (fd *FD) Pread(p []byte, off int64) (int, error) {
+	// Call incref, not readLock, because since pread specifies the
+	// offset it is independent from other reads.
+	// Similarly, using the poller doesn't make sense for pread.
+	if err := fd.incref(); err != nil {
+		return 0, err
+	}
+	if fd.IsStream && len(p) > maxRW {
+		p = p[:maxRW]
+	}
+	var (
+		n   int
+		err error
+	)
+	for {
+		n, err = syscall.Pread(fd.Sysfd, p, off)
+		if err != syscall.EINTR {
+			break
+		}
+	}
+	if err != nil {
+		n = 0
+	}
+	fd.decref()
+	err = fd.eofError(n, err)
+	return n, err
+}
+
+// ReadFrom wraps the recvfrom network call.
+func (fd *FD) ReadFrom(p []byte) (int, syscall.Sockaddr, error) {
+	if err := fd.readLock(); err != nil {
+		return 0, nil, err
+	}
+	defer fd.readUnlock()
+	if err := fd.pd.prepareRead(fd.isFile); err != nil {
+		return 0, nil, err
+	}
+	for {
+		n, sa, err := syscall.Recvfrom(fd.Sysfd, p, 0)
+		if err != nil {
+			if err == syscall.EINTR {
+				continue
+			}
+			n = 0
+			if err == syscall.EAGAIN && fd.pd.pollable() {
+				if err = fd.pd.waitRead(fd.isFile); err == nil {
+					continue
+				}
+			}
+		}
+		err = fd.eofError(n, err)
+		return n, sa, err
+	}
+}
+
+// ReadFromInet4 wraps the recvfrom network call for IPv4.
+func (fd *FD) ReadFromInet4(p []byte, from *syscall.SockaddrInet4) (int, error) {
+	if err := fd.readLock(); err != nil {
+		return 0, err
+	}
+	defer fd.readUnlock()
+	if err := fd.pd.prepareRead(fd.isFile); err != nil {
+		return 0, err
+	}
+	for {
+		n, err := unix.RecvfromInet4(fd.Sysfd, p, 0, from)
+		if err != nil {
+			if err == syscall.EINTR {
+				continue
+			}
+			n = 0
+			if err == syscall.EAGAIN && fd.pd.pollable() {
+				if err = fd.pd.waitRead(fd.isFile); err == nil {
+					continue
+				}
+			}
+		}
+		err = fd.eofError(n, err)
+		return n, err
+	}
+}
+
+// ReadFromInet6 wraps the recvfrom network call for IPv6.
+func (fd *FD) ReadFromInet6(p []byte, from *syscall.SockaddrInet6) (int, error) {
+	if err := fd.readLock(); err != nil {
+		return 0, err
+	}
+	defer fd.readUnlock()
+	if err := fd.pd.prepareRead(fd.isFile); err != nil {
+		return 0, err
+	}
+	for {
+		n, err := unix.RecvfromInet6(fd.Sysfd, p, 0, from)
+		if err != nil {
+			if err == syscall.EINTR {
+				continue
+			}
+			n = 0
+			if err == syscall.EAGAIN && fd.pd.pollable() {
+				if err = fd.pd.waitRead(fd.isFile); err == nil {
+					continue
+				}
+			}
+		}
+		err = fd.eofError(n, err)
+		return n, err
+	}
+}
+
+// ReadMsg wraps the recvmsg network call.
+func (fd *FD) ReadMsg(p []byte, oob []byte, flags int) (int, int, int, syscall.Sockaddr, error) {
+	if err := fd.readLock(); err != nil {
+		return 0, 0, 0, nil, err
+	}
+	defer fd.readUnlock()
+	if err := fd.pd.prepareRead(fd.isFile); err != nil {
+		return 0, 0, 0, nil, err
+	}
+	for {
+		n, oobn, sysflags, sa, err := syscall.Recvmsg(fd.Sysfd, p, oob, flags)
+		if err != nil {
+			if err == syscall.EINTR {
+				continue
+			}
+			// TODO(dfc) should n and oobn be set to 0
+			if err == syscall.EAGAIN && fd.pd.pollable() {
+				if err = fd.pd.waitRead(fd.isFile); err == nil {
+					continue
+				}
+			}
+		}
+		err = fd.eofError(n, err)
+		return n, oobn, sysflags, sa, err
+	}
+}
+
+// ReadMsgInet4 is ReadMsg, but specialized for syscall.SockaddrInet4.
+func (fd *FD) ReadMsgInet4(p []byte, oob []byte, flags int, sa4 *syscall.SockaddrInet4) (int, int, int, error) {
+	if err := fd.readLock(); err != nil {
+		return 0, 0, 0, err
+	}
+	defer fd.readUnlock()
+	if err := fd.pd.prepareRead(fd.isFile); err != nil {
+		return 0, 0, 0, err
+	}
+	for {
+		n, oobn, sysflags, err := unix.RecvmsgInet4(fd.Sysfd, p, oob, flags, sa4)
+		if err != nil {
+			if err == syscall.EINTR {
+				continue
+			}
+			// TODO(dfc) should n and oobn be set to 0
+			if err == syscall.EAGAIN && fd.pd.pollable() {
+				if err = fd.pd.waitRead(fd.isFile); err == nil {
+					continue
+				}
+			}
+		}
+		err = fd.eofError(n, err)
+		return n, oobn, sysflags, err
+	}
+}
+
+// ReadMsgInet6 is ReadMsg, but specialized for syscall.SockaddrInet6.
+func (fd *FD) ReadMsgInet6(p []byte, oob []byte, flags int, sa6 *syscall.SockaddrInet6) (int, int, int, error) {
+	if err := fd.readLock(); err != nil {
+		return 0, 0, 0, err
+	}
+	defer fd.readUnlock()
+	if err := fd.pd.prepareRead(fd.isFile); err != nil {
+		return 0, 0, 0, err
+	}
+	for {
+		n, oobn, sysflags, err := unix.RecvmsgInet6(fd.Sysfd, p, oob, flags, sa6)
+		if err != nil {
+			if err == syscall.EINTR {
+				continue
+			}
+			// TODO(dfc) should n and oobn be set to 0
+			if err == syscall.EAGAIN && fd.pd.pollable() {
+				if err = fd.pd.waitRead(fd.isFile); err == nil {
+					continue
+				}
+			}
+		}
+		err = fd.eofError(n, err)
+		return n, oobn, sysflags, err
+	}
+}
+
+// Write implements io.Writer.
+func (fd *FD) Write(p []byte) (int, error) {
+	if err := fd.writeLock(); err != nil {
+		return 0, err
+	}
+	defer fd.writeUnlock()
+	if err := fd.pd.prepareWrite(fd.isFile); err != nil {
+		return 0, err
+	}
+	var nn int
+	for {
+		max := len(p)
+		if fd.IsStream && max-nn > maxRW {
+			max = nn + maxRW
+		}
+		n, err := ignoringEINTRIO(syscall.Write, fd.Sysfd, p[nn:max])
+		if n > 0 {
+			nn += n
+		}
+		if nn == len(p) {
+			return nn, err
+		}
+		if err == syscall.EAGAIN && fd.pd.pollable() {
+			if err = fd.pd.waitWrite(fd.isFile); err == nil {
+				continue
+			}
+		}
+		if err != nil {
+			return nn, err
+		}
+		if n == 0 {
+			return nn, io.ErrUnexpectedEOF
+		}
+	}
+}
+
+// Pwrite wraps the pwrite system call.
+func (fd *FD) Pwrite(p []byte, off int64) (int, error) {
+	// Call incref, not writeLock, because since pwrite specifies the
+	// offset it is independent from other writes.
+	// Similarly, using the poller doesn't make sense for pwrite.
+	if err := fd.incref(); err != nil {
+		return 0, err
+	}
+	defer fd.decref()
+	var nn int
+	for {
+		max := len(p)
+		if fd.IsStream && max-nn > maxRW {
+			max = nn + maxRW
+		}
+		n, err := syscall.Pwrite(fd.Sysfd, p[nn:max], off+int64(nn))
+		if err == syscall.EINTR {
+			continue
+		}
+		if n > 0 {
+			nn += n
+		}
+		if nn == len(p) {
+			return nn, err
+		}
+		if err != nil {
+			return nn, err
+		}
+		if n == 0 {
+			return nn, io.ErrUnexpectedEOF
+		}
+	}
+}
+
+// WriteToInet4 wraps the sendto network call for IPv4 addresses.
+func (fd *FD) WriteToInet4(p []byte, sa *syscall.SockaddrInet4) (int, error) {
+	if err := fd.writeLock(); err != nil {
+		return 0, err
+	}
+	defer fd.writeUnlock()
+	if err := fd.pd.prepareWrite(fd.isFile); err != nil {
+		return 0, err
+	}
+	for {
+		err := unix.SendtoInet4(fd.Sysfd, p, 0, sa)
+		if err == syscall.EINTR {
+			continue
+		}
+		if err == syscall.EAGAIN && fd.pd.pollable() {
+			if err = fd.pd.waitWrite(fd.isFile); err == nil {
+				continue
+			}
+		}
+		if err != nil {
+			return 0, err
+		}
+		return len(p), nil
+	}
+}
+
+// WriteToInet6 wraps the sendto network call for IPv6 addresses.
+func (fd *FD) WriteToInet6(p []byte, sa *syscall.SockaddrInet6) (int, error) {
+	if err := fd.writeLock(); err != nil {
+		return 0, err
+	}
+	defer fd.writeUnlock()
+	if err := fd.pd.prepareWrite(fd.isFile); err != nil {
+		return 0, err
+	}
+	for {
+		err := unix.SendtoInet6(fd.Sysfd, p, 0, sa)
+		if err == syscall.EINTR {
+			continue
+		}
+		if err == syscall.EAGAIN && fd.pd.pollable() {
+			if err = fd.pd.waitWrite(fd.isFile); err == nil {
+				continue
+			}
+		}
+		if err != nil {
+			return 0, err
+		}
+		return len(p), nil
+	}
+}
+
+// WriteTo wraps the sendto network call.
+func (fd *FD) WriteTo(p []byte, sa syscall.Sockaddr) (int, error) {
+	if err := fd.writeLock(); err != nil {
+		return 0, err
+	}
+	defer fd.writeUnlock()
+	if err := fd.pd.prepareWrite(fd.isFile); err != nil {
+		return 0, err
+	}
+	for {
+		err := syscall.Sendto(fd.Sysfd, p, 0, sa)
+		if err == syscall.EINTR {
+			continue
+		}
+		if err == syscall.EAGAIN && fd.pd.pollable() {
+			if err = fd.pd.waitWrite(fd.isFile); err == nil {
+				continue
+			}
+		}
+		if err != nil {
+			return 0, err
+		}
+		return len(p), nil
+	}
+}
+
+// WriteMsg wraps the sendmsg network call.
+func (fd *FD) WriteMsg(p []byte, oob []byte, sa syscall.Sockaddr) (int, int, error) {
+	if err := fd.writeLock(); err != nil {
+		return 0, 0, err
+	}
+	defer fd.writeUnlock()
+	if err := fd.pd.prepareWrite(fd.isFile); err != nil {
+		return 0, 0, err
+	}
+	for {
+		n, err := syscall.SendmsgN(fd.Sysfd, p, oob, sa, 0)
+		if err == syscall.EINTR {
+			continue
+		}
+		if err == syscall.EAGAIN && fd.pd.pollable() {
+			if err = fd.pd.waitWrite(fd.isFile); err == nil {
+				continue
+			}
+		}
+		if err != nil {
+			return n, 0, err
+		}
+		return n, len(oob), err
+	}
+}
+
+// WriteMsgInet4 is WriteMsg specialized for syscall.SockaddrInet4.
+func (fd *FD) WriteMsgInet4(p []byte, oob []byte, sa *syscall.SockaddrInet4) (int, int, error) {
+	if err := fd.writeLock(); err != nil {
+		return 0, 0, err
+	}
+	defer fd.writeUnlock()
+	if err := fd.pd.prepareWrite(fd.isFile); err != nil {
+		return 0, 0, err
+	}
+	for {
+		n, err := unix.SendmsgNInet4(fd.Sysfd, p, oob, sa, 0)
+		if err == syscall.EINTR {
+			continue
+		}
+		if err == syscall.EAGAIN && fd.pd.pollable() {
+			if err = fd.pd.waitWrite(fd.isFile); err == nil {
+				continue
+			}
+		}
+		if err != nil {
+			return n, 0, err
+		}
+		return n, len(oob), err
+	}
+}
+
+// WriteMsgInet6 is WriteMsg specialized for syscall.SockaddrInet6.
+func (fd *FD) WriteMsgInet6(p []byte, oob []byte, sa *syscall.SockaddrInet6) (int, int, error) {
+	if err := fd.writeLock(); err != nil {
+		return 0, 0, err
+	}
+	defer fd.writeUnlock()
+	if err := fd.pd.prepareWrite(fd.isFile); err != nil {
+		return 0, 0, err
+	}
+	for {
+		n, err := unix.SendmsgNInet6(fd.Sysfd, p, oob, sa, 0)
+		if err == syscall.EINTR {
+			continue
+		}
+		if err == syscall.EAGAIN && fd.pd.pollable() {
+			if err = fd.pd.waitWrite(fd.isFile); err == nil {
+				continue
+			}
+		}
+		if err != nil {
+			return n, 0, err
+		}
+		return n, len(oob), err
+	}
+}
+
+// Accept wraps the accept network call.
+func (fd *FD) Accept() (int, syscall.Sockaddr, string, error) {
+	if err := fd.readLock(); err != nil {
+		return -1, nil, "", err
+	}
+	defer fd.readUnlock()
+
+	if err := fd.pd.prepareRead(fd.isFile); err != nil {
+		return -1, nil, "", err
+	}
+	for {
+		s, rsa, errcall, err := accept(fd.Sysfd)
+		if err == nil {
+			return s, rsa, "", err
+		}
+		switch err {
+		case syscall.EINTR:
+			continue
+		case syscall.EAGAIN:
+			if fd.pd.pollable() {
+				if err = fd.pd.waitRead(fd.isFile); err == nil {
+					continue
+				}
+			}
+		case syscall.ECONNABORTED:
+			// This means that a socket on the listen
+			// queue was closed before we Accept()ed it;
+			// it's a silly error, so try again.
+			continue
+		}
+		return -1, nil, errcall, err
+	}
+}
+
+// Seek wraps syscall.Seek.
+func (fd *FD) Seek(offset int64, whence int) (int64, error) {
+	if err := fd.incref(); err != nil {
+		return 0, err
+	}
+	defer fd.decref()
+	return syscall.Seek(fd.Sysfd, offset, whence)
+}
+
+// ReadDirent wraps syscall.ReadDirent.
+// We treat this like an ordinary system call rather than a call
+// that tries to fill the buffer.
+func (fd *FD) ReadDirent(buf []byte) (int, error) {
+	if err := fd.incref(); err != nil {
+		return 0, err
+	}
+	defer fd.decref()
+	for {
+		n, err := ignoringEINTRIO(syscall.ReadDirent, fd.Sysfd, buf)
+		if err != nil {
+			n = 0
+			if err == syscall.EAGAIN && fd.pd.pollable() {
+				if err = fd.pd.waitRead(fd.isFile); err == nil {
+					continue
+				}
+			}
+		}
+		// Do not call eofError; caller does not expect to see io.EOF.
+		return n, err
+	}
+}
+
+// Fchmod wraps syscall.Fchmod.
+func (fd *FD) Fchmod(mode uint32) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return ignoringEINTR(func() error {
+		return syscall.Fchmod(fd.Sysfd, mode)
+	})
+}
+
+// Fchdir wraps syscall.Fchdir.
+func (fd *FD) Fchdir() error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.Fchdir(fd.Sysfd)
+}
+
+// Fstat wraps syscall.Fstat
+func (fd *FD) Fstat(s *syscall.Stat_t) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return ignoringEINTR(func() error {
+		return syscall.Fstat(fd.Sysfd, s)
+	})
+}
+
+// tryDupCloexec indicates whether F_DUPFD_CLOEXEC should be used.
+// If the kernel doesn't support it, this is set to 0.
+var tryDupCloexec = int32(1)
+
+// DupCloseOnExec dups fd and marks it close-on-exec.
+func DupCloseOnExec(fd int) (int, string, error) {
+	if syscall.F_DUPFD_CLOEXEC != 0 && atomic.LoadInt32(&tryDupCloexec) == 1 {
+		r0, e1 := fcntl(fd, syscall.F_DUPFD_CLOEXEC, 0)
+		if e1 == nil {
+			return r0, "", nil
+		}
+		switch e1.(syscall.Errno) {
+		case syscall.EINVAL, syscall.ENOSYS:
+			// Old kernel, or js/wasm (which returns
+			// ENOSYS). Fall back to the portable way from
+			// now on.
+			atomic.StoreInt32(&tryDupCloexec, 0)
+		default:
+			return -1, "fcntl", e1
+		}
+	}
+	return dupCloseOnExecOld(fd)
+}
+
+// dupCloseOnExecOld is the traditional way to dup an fd and
+// set its O_CLOEXEC bit, using two system calls.
+func dupCloseOnExecOld(fd int) (int, string, error) {
+	syscall.ForkLock.RLock()
+	defer syscall.ForkLock.RUnlock()
+	newfd, err := syscall.Dup(fd)
+	if err != nil {
+		return -1, "dup", err
+	}
+	syscall.CloseOnExec(newfd)
+	return newfd, "", nil
+}
+
+// Dup duplicates the file descriptor.
+func (fd *FD) Dup() (int, string, error) {
+	if err := fd.incref(); err != nil {
+		return -1, "", err
+	}
+	defer fd.decref()
+	return DupCloseOnExec(fd.Sysfd)
+}
+
+// On Unix variants only, expose the IO event for the net code.
+
+// WaitWrite waits until data can be read from fd.
+func (fd *FD) WaitWrite() error {
+	return fd.pd.waitWrite(fd.isFile)
+}
+
+// WriteOnce is for testing only. It makes a single write call.
+func (fd *FD) WriteOnce(p []byte) (int, error) {
+	if err := fd.writeLock(); err != nil {
+		return 0, err
+	}
+	defer fd.writeUnlock()
+	return ignoringEINTRIO(syscall.Write, fd.Sysfd, p)
+}
+
+// RawRead invokes the user-defined function f for a read operation.
+func (fd *FD) RawRead(f func(uintptr) bool) error {
+	if err := fd.readLock(); err != nil {
+		return err
+	}
+	defer fd.readUnlock()
+	if err := fd.pd.prepareRead(fd.isFile); err != nil {
+		return err
+	}
+	for {
+		if f(uintptr(fd.Sysfd)) {
+			return nil
+		}
+		if err := fd.pd.waitRead(fd.isFile); err != nil {
+			return err
+		}
+	}
+}
+
+// RawWrite invokes the user-defined function f for a write operation.
+func (fd *FD) RawWrite(f func(uintptr) bool) error {
+	if err := fd.writeLock(); err != nil {
+		return err
+	}
+	defer fd.writeUnlock()
+	if err := fd.pd.prepareWrite(fd.isFile); err != nil {
+		return err
+	}
+	for {
+		if f(uintptr(fd.Sysfd)) {
+			return nil
+		}
+		if err := fd.pd.waitWrite(fd.isFile); err != nil {
+			return err
+		}
+	}
+}
+
+// ignoringEINTRIO is like ignoringEINTR, but just for IO calls.
+func ignoringEINTRIO(fn func(fd int, p []byte) (int, error), fd int, p []byte) (int, error) {
+	for {
+		n, err := fn(fd, p)
+		if err != syscall.EINTR {
+			return n, err
+		}
+	}
+}
diff --git a/contrib/go/_std_1.19/src/internal/poll/fd_writev_darwin.go b/contrib/go/_std_1.19/src/internal/poll/fd_writev_darwin.go
new file mode 100644
index 0000000000..b5b8998df8
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/poll/fd_writev_darwin.go
@@ -0,0 +1,17 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build darwin
+
+package poll
+
+import (
+	"syscall"
+	_ "unsafe" // for go:linkname
+)
+
+// Implemented in syscall/syscall_darwin.go.
+//
+//go:linkname writev syscall.writev
+func writev(fd int, iovecs []syscall.Iovec) (uintptr, error)
diff --git a/contrib/go/_std_1.18/src/internal/poll/fd_writev_unix.go b/contrib/go/_std_1.19/src/internal/poll/fd_writev_unix.go
index aa96d104c8..aa96d104c8 100644
--- a/contrib/go/_std_1.18/src/internal/poll/fd_writev_unix.go
+++ b/contrib/go/_std_1.19/src/internal/poll/fd_writev_unix.go
diff --git a/contrib/go/_std_1.19/src/internal/poll/hook_cloexec.go b/contrib/go/_std_1.19/src/internal/poll/hook_cloexec.go
new file mode 100644
index 0000000000..5b3cdcec28
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/poll/hook_cloexec.go
@@ -0,0 +1,12 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build dragonfly || freebsd || linux || netbsd || openbsd || solaris
+
+package poll
+
+import "syscall"
+
+// Accept4Func is used to hook the accept4 call.
+var Accept4Func func(int, int) (int, syscall.Sockaddr, error) = syscall.Accept4
diff --git a/contrib/go/_std_1.19/src/internal/poll/hook_unix.go b/contrib/go/_std_1.19/src/internal/poll/hook_unix.go
new file mode 100644
index 0000000000..1a5035675d
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/poll/hook_unix.go
@@ -0,0 +1,15 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm)
+
+package poll
+
+import "syscall"
+
+// CloseFunc is used to hook the close call.
+var CloseFunc func(int) error = syscall.Close
+
+// AcceptFunc is used to hook the accept call.
+var AcceptFunc func(int) (int, syscall.Sockaddr, error) = syscall.Accept
diff --git a/contrib/go/_std_1.18/src/internal/poll/iovec_unix.go b/contrib/go/_std_1.19/src/internal/poll/iovec_unix.go
index c1500840ac..c1500840ac 100644
--- a/contrib/go/_std_1.18/src/internal/poll/iovec_unix.go
+++ b/contrib/go/_std_1.19/src/internal/poll/iovec_unix.go
diff --git a/contrib/go/_std_1.18/src/internal/poll/sendfile_bsd.go b/contrib/go/_std_1.19/src/internal/poll/sendfile_bsd.go
index 89315a8c67..89315a8c67 100644
--- a/contrib/go/_std_1.18/src/internal/poll/sendfile_bsd.go
+++ b/contrib/go/_std_1.19/src/internal/poll/sendfile_bsd.go
diff --git a/contrib/go/_std_1.18/src/internal/poll/sendfile_linux.go b/contrib/go/_std_1.19/src/internal/poll/sendfile_linux.go
index 6e7852347b..6e7852347b 100644
--- a/contrib/go/_std_1.18/src/internal/poll/sendfile_linux.go
+++ b/contrib/go/_std_1.19/src/internal/poll/sendfile_linux.go
diff --git a/contrib/go/_std_1.19/src/internal/poll/sock_cloexec.go b/contrib/go/_std_1.19/src/internal/poll/sock_cloexec.go
new file mode 100644
index 0000000000..e106b28377
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/poll/sock_cloexec.go
@@ -0,0 +1,50 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements accept for platforms that provide a fast path for
+// setting SetNonblock and CloseOnExec.
+
+//go:build dragonfly || freebsd || linux || netbsd || openbsd || solaris
+
+package poll
+
+import "syscall"
+
+// Wrapper around the accept system call that marks the returned file
+// descriptor as nonblocking and close-on-exec.
+func accept(s int) (int, syscall.Sockaddr, string, error) {
+	ns, sa, err := Accept4Func(s, syscall.SOCK_NONBLOCK|syscall.SOCK_CLOEXEC)
+	// On Linux the accept4 system call was introduced in 2.6.28
+	// kernel and on FreeBSD it was introduced in 10 kernel. If we
+	// get an ENOSYS error on both Linux and FreeBSD, or EINVAL
+	// error on Linux, fall back to using accept.
+	switch err {
+	case nil:
+		return ns, sa, "", nil
+	default: // errors other than the ones listed
+		return -1, sa, "accept4", err
+	case syscall.ENOSYS: // syscall missing
+	case syscall.EINVAL: // some Linux use this instead of ENOSYS
+	case syscall.EACCES: // some Linux use this instead of ENOSYS
+	case syscall.EFAULT: // some Linux use this instead of ENOSYS
+	}
+
+	// See ../syscall/exec_unix.go for description of ForkLock.
+	// It is probably okay to hold the lock across syscall.Accept
+	// because we have put fd.sysfd into non-blocking mode.
+	// However, a call to the File method will put it back into
+	// blocking mode. We can't take that risk, so no use of ForkLock here.
+	ns, sa, err = AcceptFunc(s)
+	if err == nil {
+		syscall.CloseOnExec(ns)
+	}
+	if err != nil {
+		return -1, nil, "accept", err
+	}
+	if err = syscall.SetNonblock(ns, true); err != nil {
+		CloseFunc(ns)
+		return -1, nil, "setnonblock", err
+	}
+	return ns, sa, "", nil
+}
diff --git a/contrib/go/_std_1.19/src/internal/poll/sockopt.go b/contrib/go/_std_1.19/src/internal/poll/sockopt.go
new file mode 100644
index 0000000000..a7c9d115b4
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/poll/sockopt.go
@@ -0,0 +1,36 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || windows
+
+package poll
+
+import "syscall"
+
+// SetsockoptInt wraps the setsockopt network call with an int argument.
+func (fd *FD) SetsockoptInt(level, name, arg int) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.SetsockoptInt(fd.Sysfd, level, name, arg)
+}
+
+// SetsockoptInet4Addr wraps the setsockopt network call with an IPv4 address.
+func (fd *FD) SetsockoptInet4Addr(level, name int, arg [4]byte) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.SetsockoptInet4Addr(fd.Sysfd, level, name, arg)
+}
+
+// SetsockoptLinger wraps the setsockopt network call with a Linger argument.
+func (fd *FD) SetsockoptLinger(level, name int, l *syscall.Linger) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.SetsockoptLinger(fd.Sysfd, level, name, l)
+}
diff --git a/contrib/go/_std_1.18/src/internal/poll/sockopt_linux.go b/contrib/go/_std_1.19/src/internal/poll/sockopt_linux.go
index bc79c350ac..bc79c350ac 100644
--- a/contrib/go/_std_1.18/src/internal/poll/sockopt_linux.go
+++ b/contrib/go/_std_1.19/src/internal/poll/sockopt_linux.go
diff --git a/contrib/go/_std_1.19/src/internal/poll/sockopt_unix.go b/contrib/go/_std_1.19/src/internal/poll/sockopt_unix.go
new file mode 100644
index 0000000000..9cba44da9d
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/poll/sockopt_unix.go
@@ -0,0 +1,18 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix
+
+package poll
+
+import "syscall"
+
+// SetsockoptByte wraps the setsockopt network call with a byte argument.
+func (fd *FD) SetsockoptByte(level, name int, arg byte) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.SetsockoptByte(fd.Sysfd, level, name, arg)
+}
diff --git a/contrib/go/_std_1.19/src/internal/poll/sockoptip.go b/contrib/go/_std_1.19/src/internal/poll/sockoptip.go
new file mode 100644
index 0000000000..41955e1fda
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/poll/sockoptip.go
@@ -0,0 +1,27 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || windows
+
+package poll
+
+import "syscall"
+
+// SetsockoptIPMreq wraps the setsockopt network call with an IPMreq argument.
+func (fd *FD) SetsockoptIPMreq(level, name int, mreq *syscall.IPMreq) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.SetsockoptIPMreq(fd.Sysfd, level, name, mreq)
+}
+
+// SetsockoptIPv6Mreq wraps the setsockopt network call with an IPv6Mreq argument.
+func (fd *FD) SetsockoptIPv6Mreq(level, name int, mreq *syscall.IPv6Mreq) error {
+	if err := fd.incref(); err != nil {
+		return err
+	}
+	defer fd.decref()
+	return syscall.SetsockoptIPv6Mreq(fd.Sysfd, level, name, mreq)
+}
diff --git a/contrib/go/_std_1.18/src/internal/poll/splice_linux.go b/contrib/go/_std_1.19/src/internal/poll/splice_linux.go
index 43eec04a71..43eec04a71 100644
--- a/contrib/go/_std_1.18/src/internal/poll/splice_linux.go
+++ b/contrib/go/_std_1.19/src/internal/poll/splice_linux.go
diff --git a/contrib/go/_std_1.19/src/internal/poll/sys_cloexec.go b/contrib/go/_std_1.19/src/internal/poll/sys_cloexec.go
new file mode 100644
index 0000000000..7cd80019f4
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/poll/sys_cloexec.go
@@ -0,0 +1,36 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements accept for platforms that do not provide a fast path for
+// setting SetNonblock and CloseOnExec.
+
+//go:build aix || darwin || (js && wasm)
+
+package poll
+
+import (
+	"syscall"
+)
+
+// Wrapper around the accept system call that marks the returned file
+// descriptor as nonblocking and close-on-exec.
+func accept(s int) (int, syscall.Sockaddr, string, error) {
+	// See ../syscall/exec_unix.go for description of ForkLock.
+	// It is probably okay to hold the lock across syscall.Accept
+	// because we have put fd.sysfd into non-blocking mode.
+	// However, a call to the File method will put it back into
+	// blocking mode. We can't take that risk, so no use of ForkLock here.
+	ns, sa, err := AcceptFunc(s)
+	if err == nil {
+		syscall.CloseOnExec(ns)
+	}
+	if err != nil {
+		return -1, nil, "accept", err
+	}
+	if err = syscall.SetNonblock(ns, true); err != nil {
+		CloseFunc(ns)
+		return -1, nil, "setnonblock", err
+	}
+	return ns, sa, "", nil
+}
diff --git a/contrib/go/_std_1.18/src/internal/poll/writev.go b/contrib/go/_std_1.19/src/internal/poll/writev.go
index cd600b63d7..cd600b63d7 100644
--- a/contrib/go/_std_1.18/src/internal/poll/writev.go
+++ b/contrib/go/_std_1.19/src/internal/poll/writev.go
diff --git a/contrib/go/_std_1.18/src/internal/race/doc.go b/contrib/go/_std_1.19/src/internal/race/doc.go
index 8fa44ce6f1..8fa44ce6f1 100644
--- a/contrib/go/_std_1.18/src/internal/race/doc.go
+++ b/contrib/go/_std_1.19/src/internal/race/doc.go
diff --git a/contrib/go/_std_1.18/src/internal/race/norace.go b/contrib/go/_std_1.19/src/internal/race/norace.go
index 67b1305713..67b1305713 100644
--- a/contrib/go/_std_1.18/src/internal/race/norace.go
+++ b/contrib/go/_std_1.19/src/internal/race/norace.go
diff --git a/contrib/go/_std_1.18/src/internal/reflectlite/asm.s b/contrib/go/_std_1.19/src/internal/reflectlite/asm.s
index a7b69b65ba..a7b69b65ba 100644
--- a/contrib/go/_std_1.18/src/internal/reflectlite/asm.s
+++ b/contrib/go/_std_1.19/src/internal/reflectlite/asm.s
diff --git a/contrib/go/_std_1.18/src/internal/reflectlite/swapper.go b/contrib/go/_std_1.19/src/internal/reflectlite/swapper.go
index fc402bb38a..fc402bb38a 100644
--- a/contrib/go/_std_1.18/src/internal/reflectlite/swapper.go
+++ b/contrib/go/_std_1.19/src/internal/reflectlite/swapper.go
diff --git a/contrib/go/_std_1.19/src/internal/reflectlite/type.go b/contrib/go/_std_1.19/src/internal/reflectlite/type.go
new file mode 100644
index 0000000000..21e3c1278d
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/reflectlite/type.go
@@ -0,0 +1,983 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package reflectlite implements lightweight version of reflect, not using
+// any package except for "runtime" and "unsafe".
+package reflectlite
+
+import (
+	"internal/unsafeheader"
+	"unsafe"
+)
+
+// Type is the representation of a Go type.
+//
+// Not all methods apply to all kinds of types. Restrictions,
+// if any, are noted in the documentation for each method.
+// Use the Kind method to find out the kind of type before
+// calling kind-specific methods. Calling a method
+// inappropriate to the kind of type causes a run-time panic.
+//
+// Type values are comparable, such as with the == operator,
+// so they can be used as map keys.
+// Two Type values are equal if they represent identical types.
+type Type interface {
+	// Methods applicable to all types.
+
+	// Name returns the type's name within its package for a defined type.
+	// For other (non-defined) types it returns the empty string.
+	Name() string
+
+	// PkgPath returns a defined type's package path, that is, the import path
+	// that uniquely identifies the package, such as "encoding/base64".
+	// If the type was predeclared (string, error) or not defined (*T, struct{},
+	// []int, or A where A is an alias for a non-defined type), the package path
+	// will be the empty string.
+	PkgPath() string
+
+	// Size returns the number of bytes needed to store
+	// a value of the given type; it is analogous to unsafe.Sizeof.
+	Size() uintptr
+
+	// Kind returns the specific kind of this type.
+	Kind() Kind
+
+	// Implements reports whether the type implements the interface type u.
+	Implements(u Type) bool
+
+	// AssignableTo reports whether a value of the type is assignable to type u.
+	AssignableTo(u Type) bool
+
+	// Comparable reports whether values of this type are comparable.
+	Comparable() bool
+
+	// String returns a string representation of the type.
+	// The string representation may use shortened package names
+	// (e.g., base64 instead of "encoding/base64") and is not
+	// guaranteed to be unique among types. To test for type identity,
+	// compare the Types directly.
+	String() string
+
+	// Elem returns a type's element type.
+	// It panics if the type's Kind is not Ptr.
+	Elem() Type
+
+	common() *rtype
+	uncommon() *uncommonType
+}
+
+/*
+ * These data structures are known to the compiler (../../cmd/internal/reflectdata/reflect.go).
+ * A few are known to ../runtime/type.go to convey to debuggers.
+ * They are also known to ../runtime/type.go.
+ */
+
+// A Kind represents the specific kind of type that a Type represents.
+// The zero Kind is not a valid kind.
+type Kind uint
+
+const (
+	Invalid Kind = iota
+	Bool
+	Int
+	Int8
+	Int16
+	Int32
+	Int64
+	Uint
+	Uint8
+	Uint16
+	Uint32
+	Uint64
+	Uintptr
+	Float32
+	Float64
+	Complex64
+	Complex128
+	Array
+	Chan
+	Func
+	Interface
+	Map
+	Pointer
+	Slice
+	String
+	Struct
+	UnsafePointer
+)
+
+const Ptr = Pointer
+
+// tflag is used by an rtype to signal what extra type information is
+// available in the memory directly following the rtype value.
+//
+// tflag values must be kept in sync with copies in:
+//
+//	cmd/compile/internal/reflectdata/reflect.go
+//	cmd/link/internal/ld/decodesym.go
+//	runtime/type.go
+type tflag uint8
+
+const (
+	// tflagUncommon means that there is a pointer, *uncommonType,
+	// just beyond the outer type structure.
+	//
+	// For example, if t.Kind() == Struct and t.tflag&tflagUncommon != 0,
+	// then t has uncommonType data and it can be accessed as:
+	//
+	//	type tUncommon struct {
+	//		structType
+	//		u uncommonType
+	//	}
+	//	u := &(*tUncommon)(unsafe.Pointer(t)).u
+	tflagUncommon tflag = 1 << 0
+
+	// tflagExtraStar means the name in the str field has an
+	// extraneous '*' prefix. This is because for most types T in
+	// a program, the type *T also exists and reusing the str data
+	// saves binary size.
+	tflagExtraStar tflag = 1 << 1
+
+	// tflagNamed means the type has a name.
+	tflagNamed tflag = 1 << 2
+
+	// tflagRegularMemory means that equal and hash functions can treat
+	// this type as a single region of t.size bytes.
+	tflagRegularMemory tflag = 1 << 3
+)
+
+// rtype is the common implementation of most values.
+// It is embedded in other struct types.
+//
+// rtype must be kept in sync with ../runtime/type.go:/^type._type.
+type rtype struct {
+	size       uintptr
+	ptrdata    uintptr // number of bytes in the type that can contain pointers
+	hash       uint32  // hash of type; avoids computation in hash tables
+	tflag      tflag   // extra type information flags
+	align      uint8   // alignment of variable with this type
+	fieldAlign uint8   // alignment of struct field with this type
+	kind       uint8   // enumeration for C
+	// function for comparing objects of this type
+	// (ptr to object A, ptr to object B) -> ==?
+	equal     func(unsafe.Pointer, unsafe.Pointer) bool
+	gcdata    *byte   // garbage collection data
+	str       nameOff // string form
+	ptrToThis typeOff // type for pointer to this type, may be zero
+}
+
+// Method on non-interface type
+type method struct {
+	name nameOff // name of method
+	mtyp typeOff // method type (without receiver)
+	ifn  textOff // fn used in interface call (one-word receiver)
+	tfn  textOff // fn used for normal method call
+}
+
+// uncommonType is present only for defined types or types with methods
+// (if T is a defined type, the uncommonTypes for T and *T have methods).
+// Using a pointer to this struct reduces the overall size required
+// to describe a non-defined type with no methods.
+type uncommonType struct {
+	pkgPath nameOff // import path; empty for built-in types like int, string
+	mcount  uint16  // number of methods
+	xcount  uint16  // number of exported methods
+	moff    uint32  // offset from this uncommontype to [mcount]method
+	_       uint32  // unused
+}
+
+// chanDir represents a channel type's direction.
+type chanDir int
+
+const (
+	recvDir chanDir             = 1 << iota // <-chan
+	sendDir                                 // chan<-
+	bothDir = recvDir | sendDir             // chan
+)
+
+// arrayType represents a fixed array type.
+type arrayType struct {
+	rtype
+	elem  *rtype // array element type
+	slice *rtype // slice type
+	len   uintptr
+}
+
+// chanType represents a channel type.
+type chanType struct {
+	rtype
+	elem *rtype  // channel element type
+	dir  uintptr // channel direction (chanDir)
+}
+
+// funcType represents a function type.
+//
+// A *rtype for each in and out parameter is stored in an array that
+// directly follows the funcType (and possibly its uncommonType). So
+// a function type with one method, one input, and one output is:
+//
+//	struct {
+//		funcType
+//		uncommonType
+//		[2]*rtype    // [0] is in, [1] is out
+//	}
+type funcType struct {
+	rtype
+	inCount  uint16
+	outCount uint16 // top bit is set if last input parameter is ...
+}
+
+// imethod represents a method on an interface type
+type imethod struct {
+	name nameOff // name of method
+	typ  typeOff // .(*FuncType) underneath
+}
+
+// interfaceType represents an interface type.
+type interfaceType struct {
+	rtype
+	pkgPath name      // import path
+	methods []imethod // sorted by hash
+}
+
+// mapType represents a map type.
+type mapType struct {
+	rtype
+	key    *rtype // map key type
+	elem   *rtype // map element (value) type
+	bucket *rtype // internal bucket structure
+	// function for hashing keys (ptr to key, seed) -> hash
+	hasher     func(unsafe.Pointer, uintptr) uintptr
+	keysize    uint8  // size of key slot
+	valuesize  uint8  // size of value slot
+	bucketsize uint16 // size of bucket
+	flags      uint32
+}
+
+// ptrType represents a pointer type.
+type ptrType struct {
+	rtype
+	elem *rtype // pointer element (pointed at) type
+}
+
+// sliceType represents a slice type.
+type sliceType struct {
+	rtype
+	elem *rtype // slice element type
+}
+
+// Struct field
+type structField struct {
+	name   name    // name is always non-empty
+	typ    *rtype  // type of field
+	offset uintptr // byte offset of field
+}
+
+func (f *structField) embedded() bool {
+	return f.name.embedded()
+}
+
+// structType represents a struct type.
+type structType struct {
+	rtype
+	pkgPath name
+	fields  []structField // sorted by offset
+}
+
+// name is an encoded type name with optional extra data.
+//
+// The first byte is a bit field containing:
+//
+//	1<<0 the name is exported
+//	1<<1 tag data follows the name
+//	1<<2 pkgPath nameOff follows the name and tag
+//
+// The next two bytes are the data length:
+//
+//	l := uint16(data[1])<<8 | uint16(data[2])
+//
+// Bytes [3:3+l] are the string data.
+//
+// If tag data follows then bytes 3+l and 3+l+1 are the tag length,
+// with the data following.
+//
+// If the import path follows, then 4 bytes at the end of
+// the data form a nameOff. The import path is only set for concrete
+// methods that are defined in a different package than their type.
+//
+// If a name starts with "*", then the exported bit represents
+// whether the pointed to type is exported.
+type name struct {
+	bytes *byte
+}
+
+func (n name) data(off int, whySafe string) *byte {
+	return (*byte)(add(unsafe.Pointer(n.bytes), uintptr(off), whySafe))
+}
+
+func (n name) isExported() bool {
+	return (*n.bytes)&(1<<0) != 0
+}
+
+func (n name) hasTag() bool {
+	return (*n.bytes)&(1<<1) != 0
+}
+
+func (n name) embedded() bool {
+	return (*n.bytes)&(1<<3) != 0
+}
+
+// readVarint parses a varint as encoded by encoding/binary.
+// It returns the number of encoded bytes and the encoded value.
+func (n name) readVarint(off int) (int, int) {
+	v := 0
+	for i := 0; ; i++ {
+		x := *n.data(off+i, "read varint")
+		v += int(x&0x7f) << (7 * i)
+		if x&0x80 == 0 {
+			return i + 1, v
+		}
+	}
+}
+
+func (n name) name() (s string) {
+	if n.bytes == nil {
+		return
+	}
+	i, l := n.readVarint(1)
+	hdr := (*unsafeheader.String)(unsafe.Pointer(&s))
+	hdr.Data = unsafe.Pointer(n.data(1+i, "non-empty string"))
+	hdr.Len = l
+	return
+}
+
+func (n name) tag() (s string) {
+	if !n.hasTag() {
+		return ""
+	}
+	i, l := n.readVarint(1)
+	i2, l2 := n.readVarint(1 + i + l)
+	hdr := (*unsafeheader.String)(unsafe.Pointer(&s))
+	hdr.Data = unsafe.Pointer(n.data(1+i+l+i2, "non-empty string"))
+	hdr.Len = l2
+	return
+}
+
+func (n name) pkgPath() string {
+	if n.bytes == nil || *n.data(0, "name flag field")&(1<<2) == 0 {
+		return ""
+	}
+	i, l := n.readVarint(1)
+	off := 1 + i + l
+	if n.hasTag() {
+		i2, l2 := n.readVarint(off)
+		off += i2 + l2
+	}
+	var nameOff int32
+	// Note that this field may not be aligned in memory,
+	// so we cannot use a direct int32 assignment here.
+	copy((*[4]byte)(unsafe.Pointer(&nameOff))[:], (*[4]byte)(unsafe.Pointer(n.data(off, "name offset field")))[:])
+	pkgPathName := name{(*byte)(resolveTypeOff(unsafe.Pointer(n.bytes), nameOff))}
+	return pkgPathName.name()
+}
+
+/*
+ * The compiler knows the exact layout of all the data structures above.
+ * The compiler does not know about the data structures and methods below.
+ */
+
+const (
+	kindDirectIface = 1 << 5
+	kindGCProg      = 1 << 6 // Type.gc points to GC program
+	kindMask        = (1 << 5) - 1
+)
+
+// String returns the name of k.
+func (k Kind) String() string {
+	if int(k) < len(kindNames) {
+		return kindNames[k]
+	}
+	return kindNames[0]
+}
+
+var kindNames = []string{
+	Invalid:       "invalid",
+	Bool:          "bool",
+	Int:           "int",
+	Int8:          "int8",
+	Int16:         "int16",
+	Int32:         "int32",
+	Int64:         "int64",
+	Uint:          "uint",
+	Uint8:         "uint8",
+	Uint16:        "uint16",
+	Uint32:        "uint32",
+	Uint64:        "uint64",
+	Uintptr:       "uintptr",
+	Float32:       "float32",
+	Float64:       "float64",
+	Complex64:     "complex64",
+	Complex128:    "complex128",
+	Array:         "array",
+	Chan:          "chan",
+	Func:          "func",
+	Interface:     "interface",
+	Map:           "map",
+	Ptr:           "ptr",
+	Slice:         "slice",
+	String:        "string",
+	Struct:        "struct",
+	UnsafePointer: "unsafe.Pointer",
+}
+
+func (t *uncommonType) methods() []method {
+	if t.mcount == 0 {
+		return nil
+	}
+	return (*[1 << 16]method)(add(unsafe.Pointer(t), uintptr(t.moff), "t.mcount > 0"))[:t.mcount:t.mcount]
+}
+
+func (t *uncommonType) exportedMethods() []method {
+	if t.xcount == 0 {
+		return nil
+	}
+	return (*[1 << 16]method)(add(unsafe.Pointer(t), uintptr(t.moff), "t.xcount > 0"))[:t.xcount:t.xcount]
+}
+
+// resolveNameOff resolves a name offset from a base pointer.
+// The (*rtype).nameOff method is a convenience wrapper for this function.
+// Implemented in the runtime package.
+func resolveNameOff(ptrInModule unsafe.Pointer, off int32) unsafe.Pointer
+
+// resolveTypeOff resolves an *rtype offset from a base type.
+// The (*rtype).typeOff method is a convenience wrapper for this function.
+// Implemented in the runtime package.
+func resolveTypeOff(rtype unsafe.Pointer, off int32) unsafe.Pointer
+
+type nameOff int32 // offset to a name
+type typeOff int32 // offset to an *rtype
+type textOff int32 // offset from top of text section
+
+func (t *rtype) nameOff(off nameOff) name {
+	return name{(*byte)(resolveNameOff(unsafe.Pointer(t), int32(off)))}
+}
+
+func (t *rtype) typeOff(off typeOff) *rtype {
+	return (*rtype)(resolveTypeOff(unsafe.Pointer(t), int32(off)))
+}
+
+func (t *rtype) uncommon() *uncommonType {
+	if t.tflag&tflagUncommon == 0 {
+		return nil
+	}
+	switch t.Kind() {
+	case Struct:
+		return &(*structTypeUncommon)(unsafe.Pointer(t)).u
+	case Ptr:
+		type u struct {
+			ptrType
+			u uncommonType
+		}
+		return &(*u)(unsafe.Pointer(t)).u
+	case Func:
+		type u struct {
+			funcType
+			u uncommonType
+		}
+		return &(*u)(unsafe.Pointer(t)).u
+	case Slice:
+		type u struct {
+			sliceType
+			u uncommonType
+		}
+		return &(*u)(unsafe.Pointer(t)).u
+	case Array:
+		type u struct {
+			arrayType
+			u uncommonType
+		}
+		return &(*u)(unsafe.Pointer(t)).u
+	case Chan:
+		type u struct {
+			chanType
+			u uncommonType
+		}
+		return &(*u)(unsafe.Pointer(t)).u
+	case Map:
+		type u struct {
+			mapType
+			u uncommonType
+		}
+		return &(*u)(unsafe.Pointer(t)).u
+	case Interface:
+		type u struct {
+			interfaceType
+			u uncommonType
+		}
+		return &(*u)(unsafe.Pointer(t)).u
+	default:
+		type u struct {
+			rtype
+			u uncommonType
+		}
+		return &(*u)(unsafe.Pointer(t)).u
+	}
+}
+
+func (t *rtype) String() string {
+	s := t.nameOff(t.str).name()
+	if t.tflag&tflagExtraStar != 0 {
+		return s[1:]
+	}
+	return s
+}
+
+func (t *rtype) Size() uintptr { return t.size }
+
+func (t *rtype) Kind() Kind { return Kind(t.kind & kindMask) }
+
+func (t *rtype) pointers() bool { return t.ptrdata != 0 }
+
+func (t *rtype) common() *rtype { return t }
+
+func (t *rtype) exportedMethods() []method {
+	ut := t.uncommon()
+	if ut == nil {
+		return nil
+	}
+	return ut.exportedMethods()
+}
+
+func (t *rtype) NumMethod() int {
+	if t.Kind() == Interface {
+		tt := (*interfaceType)(unsafe.Pointer(t))
+		return tt.NumMethod()
+	}
+	return len(t.exportedMethods())
+}
+
+func (t *rtype) PkgPath() string {
+	if t.tflag&tflagNamed == 0 {
+		return ""
+	}
+	ut := t.uncommon()
+	if ut == nil {
+		return ""
+	}
+	return t.nameOff(ut.pkgPath).name()
+}
+
+func (t *rtype) hasName() bool {
+	return t.tflag&tflagNamed != 0
+}
+
+func (t *rtype) Name() string {
+	if !t.hasName() {
+		return ""
+	}
+	s := t.String()
+	i := len(s) - 1
+	sqBrackets := 0
+	for i >= 0 && (s[i] != '.' || sqBrackets != 0) {
+		switch s[i] {
+		case ']':
+			sqBrackets++
+		case '[':
+			sqBrackets--
+		}
+		i--
+	}
+	return s[i+1:]
+}
+
+func (t *rtype) chanDir() chanDir {
+	if t.Kind() != Chan {
+		panic("reflect: chanDir of non-chan type")
+	}
+	tt := (*chanType)(unsafe.Pointer(t))
+	return chanDir(tt.dir)
+}
+
+func (t *rtype) Elem() Type {
+	switch t.Kind() {
+	case Array:
+		tt := (*arrayType)(unsafe.Pointer(t))
+		return toType(tt.elem)
+	case Chan:
+		tt := (*chanType)(unsafe.Pointer(t))
+		return toType(tt.elem)
+	case Map:
+		tt := (*mapType)(unsafe.Pointer(t))
+		return toType(tt.elem)
+	case Ptr:
+		tt := (*ptrType)(unsafe.Pointer(t))
+		return toType(tt.elem)
+	case Slice:
+		tt := (*sliceType)(unsafe.Pointer(t))
+		return toType(tt.elem)
+	}
+	panic("reflect: Elem of invalid type")
+}
+
+func (t *rtype) In(i int) Type {
+	if t.Kind() != Func {
+		panic("reflect: In of non-func type")
+	}
+	tt := (*funcType)(unsafe.Pointer(t))
+	return toType(tt.in()[i])
+}
+
+func (t *rtype) Key() Type {
+	if t.Kind() != Map {
+		panic("reflect: Key of non-map type")
+	}
+	tt := (*mapType)(unsafe.Pointer(t))
+	return toType(tt.key)
+}
+
+func (t *rtype) Len() int {
+	if t.Kind() != Array {
+		panic("reflect: Len of non-array type")
+	}
+	tt := (*arrayType)(unsafe.Pointer(t))
+	return int(tt.len)
+}
+
+func (t *rtype) NumField() int {
+	if t.Kind() != Struct {
+		panic("reflect: NumField of non-struct type")
+	}
+	tt := (*structType)(unsafe.Pointer(t))
+	return len(tt.fields)
+}
+
+func (t *rtype) NumIn() int {
+	if t.Kind() != Func {
+		panic("reflect: NumIn of non-func type")
+	}
+	tt := (*funcType)(unsafe.Pointer(t))
+	return int(tt.inCount)
+}
+
+func (t *rtype) NumOut() int {
+	if t.Kind() != Func {
+		panic("reflect: NumOut of non-func type")
+	}
+	tt := (*funcType)(unsafe.Pointer(t))
+	return len(tt.out())
+}
+
+func (t *rtype) Out(i int) Type {
+	if t.Kind() != Func {
+		panic("reflect: Out of non-func type")
+	}
+	tt := (*funcType)(unsafe.Pointer(t))
+	return toType(tt.out()[i])
+}
+
+func (t *funcType) in() []*rtype {
+	uadd := unsafe.Sizeof(*t)
+	if t.tflag&tflagUncommon != 0 {
+		uadd += unsafe.Sizeof(uncommonType{})
+	}
+	if t.inCount == 0 {
+		return nil
+	}
+	return (*[1 << 20]*rtype)(add(unsafe.Pointer(t), uadd, "t.inCount > 0"))[:t.inCount:t.inCount]
+}
+
+func (t *funcType) out() []*rtype {
+	uadd := unsafe.Sizeof(*t)
+	if t.tflag&tflagUncommon != 0 {
+		uadd += unsafe.Sizeof(uncommonType{})
+	}
+	outCount := t.outCount & (1<<15 - 1)
+	if outCount == 0 {
+		return nil
+	}
+	return (*[1 << 20]*rtype)(add(unsafe.Pointer(t), uadd, "outCount > 0"))[t.inCount : t.inCount+outCount : t.inCount+outCount]
+}
+
+// add returns p+x.
+//
+// The whySafe string is ignored, so that the function still inlines
+// as efficiently as p+x, but all call sites should use the string to
+// record why the addition is safe, which is to say why the addition
+// does not cause x to advance to the very end of p's allocation
+// and therefore point incorrectly at the next block in memory.
+func add(p unsafe.Pointer, x uintptr, whySafe string) unsafe.Pointer {
+	return unsafe.Pointer(uintptr(p) + x)
+}
+
+// NumMethod returns the number of interface methods in the type's method set.
+func (t *interfaceType) NumMethod() int { return len(t.methods) }
+
+// TypeOf returns the reflection Type that represents the dynamic type of i.
+// If i is a nil interface value, TypeOf returns nil.
+func TypeOf(i any) Type {
+	eface := *(*emptyInterface)(unsafe.Pointer(&i))
+	return toType(eface.typ)
+}
+
+func (t *rtype) Implements(u Type) bool {
+	if u == nil {
+		panic("reflect: nil type passed to Type.Implements")
+	}
+	if u.Kind() != Interface {
+		panic("reflect: non-interface type passed to Type.Implements")
+	}
+	return implements(u.(*rtype), t)
+}
+
+func (t *rtype) AssignableTo(u Type) bool {
+	if u == nil {
+		panic("reflect: nil type passed to Type.AssignableTo")
+	}
+	uu := u.(*rtype)
+	return directlyAssignable(uu, t) || implements(uu, t)
+}
+
+func (t *rtype) Comparable() bool {
+	return t.equal != nil
+}
+
+// implements reports whether the type V implements the interface type T.
+func implements(T, V *rtype) bool {
+	if T.Kind() != Interface {
+		return false
+	}
+	t := (*interfaceType)(unsafe.Pointer(T))
+	if len(t.methods) == 0 {
+		return true
+	}
+
+	// The same algorithm applies in both cases, but the
+	// method tables for an interface type and a concrete type
+	// are different, so the code is duplicated.
+	// In both cases the algorithm is a linear scan over the two
+	// lists - T's methods and V's methods - simultaneously.
+	// Since method tables are stored in a unique sorted order
+	// (alphabetical, with no duplicate method names), the scan
+	// through V's methods must hit a match for each of T's
+	// methods along the way, or else V does not implement T.
+	// This lets us run the scan in overall linear time instead of
+	// the quadratic time  a naive search would require.
+	// See also ../runtime/iface.go.
+	if V.Kind() == Interface {
+		v := (*interfaceType)(unsafe.Pointer(V))
+		i := 0
+		for j := 0; j < len(v.methods); j++ {
+			tm := &t.methods[i]
+			tmName := t.nameOff(tm.name)
+			vm := &v.methods[j]
+			vmName := V.nameOff(vm.name)
+			if vmName.name() == tmName.name() && V.typeOff(vm.typ) == t.typeOff(tm.typ) {
+				if !tmName.isExported() {
+					tmPkgPath := tmName.pkgPath()
+					if tmPkgPath == "" {
+						tmPkgPath = t.pkgPath.name()
+					}
+					vmPkgPath := vmName.pkgPath()
+					if vmPkgPath == "" {
+						vmPkgPath = v.pkgPath.name()
+					}
+					if tmPkgPath != vmPkgPath {
+						continue
+					}
+				}
+				if i++; i >= len(t.methods) {
+					return true
+				}
+			}
+		}
+		return false
+	}
+
+	v := V.uncommon()
+	if v == nil {
+		return false
+	}
+	i := 0
+	vmethods := v.methods()
+	for j := 0; j < int(v.mcount); j++ {
+		tm := &t.methods[i]
+		tmName := t.nameOff(tm.name)
+		vm := vmethods[j]
+		vmName := V.nameOff(vm.name)
+		if vmName.name() == tmName.name() && V.typeOff(vm.mtyp) == t.typeOff(tm.typ) {
+			if !tmName.isExported() {
+				tmPkgPath := tmName.pkgPath()
+				if tmPkgPath == "" {
+					tmPkgPath = t.pkgPath.name()
+				}
+				vmPkgPath := vmName.pkgPath()
+				if vmPkgPath == "" {
+					vmPkgPath = V.nameOff(v.pkgPath).name()
+				}
+				if tmPkgPath != vmPkgPath {
+					continue
+				}
+			}
+			if i++; i >= len(t.methods) {
+				return true
+			}
+		}
+	}
+	return false
+}
+
+// directlyAssignable reports whether a value x of type V can be directly
+// assigned (using memmove) to a value of type T.
+// https://golang.org/doc/go_spec.html#Assignability
+// Ignoring the interface rules (implemented elsewhere)
+// and the ideal constant rules (no ideal constants at run time).
+func directlyAssignable(T, V *rtype) bool {
+	// x's type V is identical to T?
+	if T == V {
+		return true
+	}
+
+	// Otherwise at least one of T and V must not be defined
+	// and they must have the same kind.
+	if T.hasName() && V.hasName() || T.Kind() != V.Kind() {
+		return false
+	}
+
+	// x's type T and V must  have identical underlying types.
+	return haveIdenticalUnderlyingType(T, V, true)
+}
+
+func haveIdenticalType(T, V Type, cmpTags bool) bool {
+	if cmpTags {
+		return T == V
+	}
+
+	if T.Name() != V.Name() || T.Kind() != V.Kind() {
+		return false
+	}
+
+	return haveIdenticalUnderlyingType(T.common(), V.common(), false)
+}
+
+func haveIdenticalUnderlyingType(T, V *rtype, cmpTags bool) bool {
+	if T == V {
+		return true
+	}
+
+	kind := T.Kind()
+	if kind != V.Kind() {
+		return false
+	}
+
+	// Non-composite types of equal kind have same underlying type
+	// (the predefined instance of the type).
+	if Bool <= kind && kind <= Complex128 || kind == String || kind == UnsafePointer {
+		return true
+	}
+
+	// Composite types.
+	switch kind {
+	case Array:
+		return T.Len() == V.Len() && haveIdenticalType(T.Elem(), V.Elem(), cmpTags)
+
+	case Chan:
+		// Special case:
+		// x is a bidirectional channel value, T is a channel type,
+		// and x's type V and T have identical element types.
+		if V.chanDir() == bothDir && haveIdenticalType(T.Elem(), V.Elem(), cmpTags) {
+			return true
+		}
+
+		// Otherwise continue test for identical underlying type.
+		return V.chanDir() == T.chanDir() && haveIdenticalType(T.Elem(), V.Elem(), cmpTags)
+
+	case Func:
+		t := (*funcType)(unsafe.Pointer(T))
+		v := (*funcType)(unsafe.Pointer(V))
+		if t.outCount != v.outCount || t.inCount != v.inCount {
+			return false
+		}
+		for i := 0; i < t.NumIn(); i++ {
+			if !haveIdenticalType(t.In(i), v.In(i), cmpTags) {
+				return false
+			}
+		}
+		for i := 0; i < t.NumOut(); i++ {
+			if !haveIdenticalType(t.Out(i), v.Out(i), cmpTags) {
+				return false
+			}
+		}
+		return true
+
+	case Interface:
+		t := (*interfaceType)(unsafe.Pointer(T))
+		v := (*interfaceType)(unsafe.Pointer(V))
+		if len(t.methods) == 0 && len(v.methods) == 0 {
+			return true
+		}
+		// Might have the same methods but still
+		// need a run time conversion.
+		return false
+
+	case Map:
+		return haveIdenticalType(T.Key(), V.Key(), cmpTags) && haveIdenticalType(T.Elem(), V.Elem(), cmpTags)
+
+	case Ptr, Slice:
+		return haveIdenticalType(T.Elem(), V.Elem(), cmpTags)
+
+	case Struct:
+		t := (*structType)(unsafe.Pointer(T))
+		v := (*structType)(unsafe.Pointer(V))
+		if len(t.fields) != len(v.fields) {
+			return false
+		}
+		if t.pkgPath.name() != v.pkgPath.name() {
+			return false
+		}
+		for i := range t.fields {
+			tf := &t.fields[i]
+			vf := &v.fields[i]
+			if tf.name.name() != vf.name.name() {
+				return false
+			}
+			if !haveIdenticalType(tf.typ, vf.typ, cmpTags) {
+				return false
+			}
+			if cmpTags && tf.name.tag() != vf.name.tag() {
+				return false
+			}
+			if tf.offset != vf.offset {
+				return false
+			}
+			if tf.embedded() != vf.embedded() {
+				return false
+			}
+		}
+		return true
+	}
+
+	return false
+}
+
+type structTypeUncommon struct {
+	structType
+	u uncommonType
+}
+
+// toType converts from a *rtype to a Type that can be returned
+// to the client of package reflect. In gc, the only concern is that
+// a nil *rtype must be replaced by a nil Type, but in gccgo this
+// function takes care of ensuring that multiple *rtype for the same
+// type are coalesced into a single Type.
+func toType(t *rtype) Type {
+	if t == nil {
+		return nil
+	}
+	return t
+}
+
+// ifaceIndir reports whether t is stored indirectly in an interface value.
+func ifaceIndir(t *rtype) bool {
+	return t.kind&kindDirectIface == 0
+}
diff --git a/contrib/go/_std_1.19/src/internal/reflectlite/value.go b/contrib/go/_std_1.19/src/internal/reflectlite/value.go
new file mode 100644
index 0000000000..b9bca3ab44
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/reflectlite/value.go
@@ -0,0 +1,477 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package reflectlite
+
+import (
+	"internal/goarch"
+	"internal/unsafeheader"
+	"runtime"
+	"unsafe"
+)
+
+// Value is the reflection interface to a Go value.
+//
+// Not all methods apply to all kinds of values. Restrictions,
+// if any, are noted in the documentation for each method.
+// Use the Kind method to find out the kind of value before
+// calling kind-specific methods. Calling a method
+// inappropriate to the kind of type causes a run time panic.
+//
+// The zero Value represents no value.
+// Its IsValid method returns false, its Kind method returns Invalid,
+// its String method returns "<invalid Value>", and all other methods panic.
+// Most functions and methods never return an invalid value.
+// If one does, its documentation states the conditions explicitly.
+//
+// A Value can be used concurrently by multiple goroutines provided that
+// the underlying Go value can be used concurrently for the equivalent
+// direct operations.
+//
+// To compare two Values, compare the results of the Interface method.
+// Using == on two Values does not compare the underlying values
+// they represent.
+type Value struct {
+	// typ holds the type of the value represented by a Value.
+	typ *rtype
+
+	// Pointer-valued data or, if flagIndir is set, pointer to data.
+	// Valid when either flagIndir is set or typ.pointers() is true.
+	ptr unsafe.Pointer
+
+	// flag holds metadata about the value.
+	// The lowest bits are flag bits:
+	//	- flagStickyRO: obtained via unexported not embedded field, so read-only
+	//	- flagEmbedRO: obtained via unexported embedded field, so read-only
+	//	- flagIndir: val holds a pointer to the data
+	//	- flagAddr: v.CanAddr is true (implies flagIndir)
+	// Value cannot represent method values.
+	// The next five bits give the Kind of the value.
+	// This repeats typ.Kind() except for method values.
+	// The remaining 23+ bits give a method number for method values.
+	// If flag.kind() != Func, code can assume that flagMethod is unset.
+	// If ifaceIndir(typ), code can assume that flagIndir is set.
+	flag
+
+	// A method value represents a curried method invocation
+	// like r.Read for some receiver r. The typ+val+flag bits describe
+	// the receiver r, but the flag's Kind bits say Func (methods are
+	// functions), and the top bits of the flag give the method number
+	// in r's type's method table.
+}
+
+type flag uintptr
+
+const (
+	flagKindWidth        = 5 // there are 27 kinds
+	flagKindMask    flag = 1<<flagKindWidth - 1
+	flagStickyRO    flag = 1 << 5
+	flagEmbedRO     flag = 1 << 6
+	flagIndir       flag = 1 << 7
+	flagAddr        flag = 1 << 8
+	flagMethod      flag = 1 << 9
+	flagMethodShift      = 10
+	flagRO          flag = flagStickyRO | flagEmbedRO
+)
+
+func (f flag) kind() Kind {
+	return Kind(f & flagKindMask)
+}
+
+func (f flag) ro() flag {
+	if f&flagRO != 0 {
+		return flagStickyRO
+	}
+	return 0
+}
+
+// pointer returns the underlying pointer represented by v.
+// v.Kind() must be Pointer, Map, Chan, Func, or UnsafePointer
+func (v Value) pointer() unsafe.Pointer {
+	if v.typ.size != goarch.PtrSize || !v.typ.pointers() {
+		panic("can't call pointer on a non-pointer Value")
+	}
+	if v.flag&flagIndir != 0 {
+		return *(*unsafe.Pointer)(v.ptr)
+	}
+	return v.ptr
+}
+
+// packEface converts v to the empty interface.
+func packEface(v Value) any {
+	t := v.typ
+	var i any
+	e := (*emptyInterface)(unsafe.Pointer(&i))
+	// First, fill in the data portion of the interface.
+	switch {
+	case ifaceIndir(t):
+		if v.flag&flagIndir == 0 {
+			panic("bad indir")
+		}
+		// Value is indirect, and so is the interface we're making.
+		ptr := v.ptr
+		if v.flag&flagAddr != 0 {
+			// TODO: pass safe boolean from valueInterface so
+			// we don't need to copy if safe==true?
+			c := unsafe_New(t)
+			typedmemmove(t, c, ptr)
+			ptr = c
+		}
+		e.word = ptr
+	case v.flag&flagIndir != 0:
+		// Value is indirect, but interface is direct. We need
+		// to load the data at v.ptr into the interface data word.
+		e.word = *(*unsafe.Pointer)(v.ptr)
+	default:
+		// Value is direct, and so is the interface.
+		e.word = v.ptr
+	}
+	// Now, fill in the type portion. We're very careful here not
+	// to have any operation between the e.word and e.typ assignments
+	// that would let the garbage collector observe the partially-built
+	// interface value.
+	e.typ = t
+	return i
+}
+
+// unpackEface converts the empty interface i to a Value.
+func unpackEface(i any) Value {
+	e := (*emptyInterface)(unsafe.Pointer(&i))
+	// NOTE: don't read e.word until we know whether it is really a pointer or not.
+	t := e.typ
+	if t == nil {
+		return Value{}
+	}
+	f := flag(t.Kind())
+	if ifaceIndir(t) {
+		f |= flagIndir
+	}
+	return Value{t, e.word, f}
+}
+
+// A ValueError occurs when a Value method is invoked on
+// a Value that does not support it. Such cases are documented
+// in the description of each method.
+type ValueError struct {
+	Method string
+	Kind   Kind
+}
+
+func (e *ValueError) Error() string {
+	if e.Kind == 0 {
+		return "reflect: call of " + e.Method + " on zero Value"
+	}
+	return "reflect: call of " + e.Method + " on " + e.Kind.String() + " Value"
+}
+
+// methodName returns the name of the calling method,
+// assumed to be two stack frames above.
+func methodName() string {
+	pc, _, _, _ := runtime.Caller(2)
+	f := runtime.FuncForPC(pc)
+	if f == nil {
+		return "unknown method"
+	}
+	return f.Name()
+}
+
+// emptyInterface is the header for an interface{} value.
+type emptyInterface struct {
+	typ  *rtype
+	word unsafe.Pointer
+}
+
+// mustBeExported panics if f records that the value was obtained using
+// an unexported field.
+func (f flag) mustBeExported() {
+	if f == 0 {
+		panic(&ValueError{methodName(), 0})
+	}
+	if f&flagRO != 0 {
+		panic("reflect: " + methodName() + " using value obtained using unexported field")
+	}
+}
+
+// mustBeAssignable panics if f records that the value is not assignable,
+// which is to say that either it was obtained using an unexported field
+// or it is not addressable.
+func (f flag) mustBeAssignable() {
+	if f == 0 {
+		panic(&ValueError{methodName(), Invalid})
+	}
+	// Assignable if addressable and not read-only.
+	if f&flagRO != 0 {
+		panic("reflect: " + methodName() + " using value obtained using unexported field")
+	}
+	if f&flagAddr == 0 {
+		panic("reflect: " + methodName() + " using unaddressable value")
+	}
+}
+
+// CanSet reports whether the value of v can be changed.
+// A Value can be changed only if it is addressable and was not
+// obtained by the use of unexported struct fields.
+// If CanSet returns false, calling Set or any type-specific
+// setter (e.g., SetBool, SetInt) will panic.
+func (v Value) CanSet() bool {
+	return v.flag&(flagAddr|flagRO) == flagAddr
+}
+
+// Elem returns the value that the interface v contains
+// or that the pointer v points to.
+// It panics if v's Kind is not Interface or Pointer.
+// It returns the zero Value if v is nil.
+func (v Value) Elem() Value {
+	k := v.kind()
+	switch k {
+	case Interface:
+		var eface any
+		if v.typ.NumMethod() == 0 {
+			eface = *(*any)(v.ptr)
+		} else {
+			eface = (any)(*(*interface {
+				M()
+			})(v.ptr))
+		}
+		x := unpackEface(eface)
+		if x.flag != 0 {
+			x.flag |= v.flag.ro()
+		}
+		return x
+	case Pointer:
+		ptr := v.ptr
+		if v.flag&flagIndir != 0 {
+			ptr = *(*unsafe.Pointer)(ptr)
+		}
+		// The returned value's address is v's value.
+		if ptr == nil {
+			return Value{}
+		}
+		tt := (*ptrType)(unsafe.Pointer(v.typ))
+		typ := tt.elem
+		fl := v.flag&flagRO | flagIndir | flagAddr
+		fl |= flag(typ.Kind())
+		return Value{typ, ptr, fl}
+	}
+	panic(&ValueError{"reflectlite.Value.Elem", v.kind()})
+}
+
+func valueInterface(v Value) any {
+	if v.flag == 0 {
+		panic(&ValueError{"reflectlite.Value.Interface", 0})
+	}
+
+	if v.kind() == Interface {
+		// Special case: return the element inside the interface.
+		// Empty interface has one layout, all interfaces with
+		// methods have a second layout.
+		if v.numMethod() == 0 {
+			return *(*any)(v.ptr)
+		}
+		return *(*interface {
+			M()
+		})(v.ptr)
+	}
+
+	// TODO: pass safe to packEface so we don't need to copy if safe==true?
+	return packEface(v)
+}
+
+// IsNil reports whether its argument v is nil. The argument must be
+// a chan, func, interface, map, pointer, or slice value; if it is
+// not, IsNil panics. Note that IsNil is not always equivalent to a
+// regular comparison with nil in Go. For example, if v was created
+// by calling ValueOf with an uninitialized interface variable i,
+// i==nil will be true but v.IsNil will panic as v will be the zero
+// Value.
+func (v Value) IsNil() bool {
+	k := v.kind()
+	switch k {
+	case Chan, Func, Map, Pointer, UnsafePointer:
+		// if v.flag&flagMethod != 0 {
+		// 	return false
+		// }
+		ptr := v.ptr
+		if v.flag&flagIndir != 0 {
+			ptr = *(*unsafe.Pointer)(ptr)
+		}
+		return ptr == nil
+	case Interface, Slice:
+		// Both interface and slice are nil if first word is 0.
+		// Both are always bigger than a word; assume flagIndir.
+		return *(*unsafe.Pointer)(v.ptr) == nil
+	}
+	panic(&ValueError{"reflectlite.Value.IsNil", v.kind()})
+}
+
+// IsValid reports whether v represents a value.
+// It returns false if v is the zero Value.
+// If IsValid returns false, all other methods except String panic.
+// Most functions and methods never return an invalid Value.
+// If one does, its documentation states the conditions explicitly.
+func (v Value) IsValid() bool {
+	return v.flag != 0
+}
+
+// Kind returns v's Kind.
+// If v is the zero Value (IsValid returns false), Kind returns Invalid.
+func (v Value) Kind() Kind {
+	return v.kind()
+}
+
+// implemented in runtime:
+func chanlen(unsafe.Pointer) int
+func maplen(unsafe.Pointer) int
+
+// Len returns v's length.
+// It panics if v's Kind is not Array, Chan, Map, Slice, or String.
+func (v Value) Len() int {
+	k := v.kind()
+	switch k {
+	case Array:
+		tt := (*arrayType)(unsafe.Pointer(v.typ))
+		return int(tt.len)
+	case Chan:
+		return chanlen(v.pointer())
+	case Map:
+		return maplen(v.pointer())
+	case Slice:
+		// Slice is bigger than a word; assume flagIndir.
+		return (*unsafeheader.Slice)(v.ptr).Len
+	case String:
+		// String is bigger than a word; assume flagIndir.
+		return (*unsafeheader.String)(v.ptr).Len
+	}
+	panic(&ValueError{"reflect.Value.Len", v.kind()})
+}
+
+// NumMethod returns the number of exported methods in the value's method set.
+func (v Value) numMethod() int {
+	if v.typ == nil {
+		panic(&ValueError{"reflectlite.Value.NumMethod", Invalid})
+	}
+	return v.typ.NumMethod()
+}
+
+// Set assigns x to the value v.
+// It panics if CanSet returns false.
+// As in Go, x's value must be assignable to v's type.
+func (v Value) Set(x Value) {
+	v.mustBeAssignable()
+	x.mustBeExported() // do not let unexported x leak
+	var target unsafe.Pointer
+	if v.kind() == Interface {
+		target = v.ptr
+	}
+	x = x.assignTo("reflectlite.Set", v.typ, target)
+	if x.flag&flagIndir != 0 {
+		typedmemmove(v.typ, v.ptr, x.ptr)
+	} else {
+		*(*unsafe.Pointer)(v.ptr) = x.ptr
+	}
+}
+
+// Type returns v's type.
+func (v Value) Type() Type {
+	f := v.flag
+	if f == 0 {
+		panic(&ValueError{"reflectlite.Value.Type", Invalid})
+	}
+	// Method values not supported.
+	return v.typ
+}
+
+/*
+ * constructors
+ */
+
+// implemented in package runtime
+func unsafe_New(*rtype) unsafe.Pointer
+
+// ValueOf returns a new Value initialized to the concrete value
+// stored in the interface i. ValueOf(nil) returns the zero Value.
+func ValueOf(i any) Value {
+	if i == nil {
+		return Value{}
+	}
+
+	// TODO: Maybe allow contents of a Value to live on the stack.
+	// For now we make the contents always escape to the heap. It
+	// makes life easier in a few places (see chanrecv/mapassign
+	// comment below).
+	escapes(i)
+
+	return unpackEface(i)
+}
+
+// assignTo returns a value v that can be assigned directly to typ.
+// It panics if v is not assignable to typ.
+// For a conversion to an interface type, target is a suggested scratch space to use.
+func (v Value) assignTo(context string, dst *rtype, target unsafe.Pointer) Value {
+	// if v.flag&flagMethod != 0 {
+	// 	v = makeMethodValue(context, v)
+	// }
+
+	switch {
+	case directlyAssignable(dst, v.typ):
+		// Overwrite type so that they match.
+		// Same memory layout, so no harm done.
+		fl := v.flag&(flagAddr|flagIndir) | v.flag.ro()
+		fl |= flag(dst.Kind())
+		return Value{dst, v.ptr, fl}
+
+	case implements(dst, v.typ):
+		if target == nil {
+			target = unsafe_New(dst)
+		}
+		if v.Kind() == Interface && v.IsNil() {
+			// A nil ReadWriter passed to nil Reader is OK,
+			// but using ifaceE2I below will panic.
+			// Avoid the panic by returning a nil dst (e.g., Reader) explicitly.
+			return Value{dst, nil, flag(Interface)}
+		}
+		x := valueInterface(v)
+		if dst.NumMethod() == 0 {
+			*(*any)(target) = x
+		} else {
+			ifaceE2I(dst, x, target)
+		}
+		return Value{dst, target, flagIndir | flag(Interface)}
+	}
+
+	// Failed.
+	panic(context + ": value of type " + v.typ.String() + " is not assignable to type " + dst.String())
+}
+
+// arrayAt returns the i-th element of p,
+// an array whose elements are eltSize bytes wide.
+// The array pointed at by p must have at least i+1 elements:
+// it is invalid (but impossible to check here) to pass i >= len,
+// because then the result will point outside the array.
+// whySafe must explain why i < len. (Passing "i < len" is fine;
+// the benefit is to surface this assumption at the call site.)
+func arrayAt(p unsafe.Pointer, i int, eltSize uintptr, whySafe string) unsafe.Pointer {
+	return add(p, uintptr(i)*eltSize, "i < len")
+}
+
+func ifaceE2I(t *rtype, src any, dst unsafe.Pointer)
+
+// typedmemmove copies a value of type t to dst from src.
+//
+//go:noescape
+func typedmemmove(t *rtype, dst, src unsafe.Pointer)
+
+// Dummy annotation marking that the value x escapes,
+// for use in cases where the reflect code is so clever that
+// the compiler cannot follow.
+func escapes(x any) {
+	if dummy.b {
+		dummy.x = x
+	}
+}
+
+var dummy struct {
+	b bool
+	x any
+}
diff --git a/contrib/go/_std_1.18/src/internal/singleflight/singleflight.go b/contrib/go/_std_1.19/src/internal/singleflight/singleflight.go
index 07b3f40ec0..07b3f40ec0 100644
--- a/contrib/go/_std_1.18/src/internal/singleflight/singleflight.go
+++ b/contrib/go/_std_1.19/src/internal/singleflight/singleflight.go
diff --git a/contrib/go/_std_1.18/src/internal/syscall/execenv/execenv_default.go b/contrib/go/_std_1.19/src/internal/syscall/execenv/execenv_default.go
index 335647c638..335647c638 100644
--- a/contrib/go/_std_1.18/src/internal/syscall/execenv/execenv_default.go
+++ b/contrib/go/_std_1.19/src/internal/syscall/execenv/execenv_default.go
diff --git a/contrib/go/_std_1.18/src/internal/syscall/unix/asm_darwin.s b/contrib/go/_std_1.19/src/internal/syscall/unix/asm_darwin.s
index 8fbdc1d866..8fbdc1d866 100644
--- a/contrib/go/_std_1.18/src/internal/syscall/unix/asm_darwin.s
+++ b/contrib/go/_std_1.19/src/internal/syscall/unix/asm_darwin.s
diff --git a/contrib/go/_std_1.19/src/internal/syscall/unix/at.go b/contrib/go/_std_1.19/src/internal/syscall/unix/at.go
new file mode 100644
index 0000000000..965162e3d2
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/syscall/unix/at.go
@@ -0,0 +1,42 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build linux || openbsd || netbsd || dragonfly
+
+package unix
+
+import (
+	"syscall"
+	"unsafe"
+)
+
+func Unlinkat(dirfd int, path string, flags int) error {
+	var p *byte
+	p, err := syscall.BytePtrFromString(path)
+	if err != nil {
+		return err
+	}
+
+	_, _, errno := syscall.Syscall(unlinkatTrap, uintptr(dirfd), uintptr(unsafe.Pointer(p)), uintptr(flags))
+	if errno != 0 {
+		return errno
+	}
+
+	return nil
+}
+
+func Openat(dirfd int, path string, flags int, perm uint32) (int, error) {
+	var p *byte
+	p, err := syscall.BytePtrFromString(path)
+	if err != nil {
+		return 0, err
+	}
+
+	fd, _, errno := syscall.Syscall6(openatTrap, uintptr(dirfd), uintptr(unsafe.Pointer(p)), uintptr(flags), uintptr(perm), 0, 0)
+	if errno != 0 {
+		return 0, errno
+	}
+
+	return int(fd), nil
+}
diff --git a/contrib/go/_std_1.18/src/internal/syscall/unix/at_darwin.go b/contrib/go/_std_1.19/src/internal/syscall/unix/at_darwin.go
index a88a27e0c6..a88a27e0c6 100644
--- a/contrib/go/_std_1.18/src/internal/syscall/unix/at_darwin.go
+++ b/contrib/go/_std_1.19/src/internal/syscall/unix/at_darwin.go
diff --git a/contrib/go/_std_1.19/src/internal/syscall/unix/at_fstatat.go b/contrib/go/_std_1.19/src/internal/syscall/unix/at_fstatat.go
new file mode 100644
index 0000000000..25318d2014
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/syscall/unix/at_fstatat.go
@@ -0,0 +1,28 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build (linux && !loong64) || openbsd || netbsd || dragonfly
+
+package unix
+
+import (
+	"syscall"
+	"unsafe"
+)
+
+func Fstatat(dirfd int, path string, stat *syscall.Stat_t, flags int) error {
+	var p *byte
+	p, err := syscall.BytePtrFromString(path)
+	if err != nil {
+		return err
+	}
+
+	_, _, errno := syscall.Syscall6(fstatatTrap, uintptr(dirfd), uintptr(unsafe.Pointer(p)), uintptr(unsafe.Pointer(stat)), uintptr(flags), 0, 0)
+	if errno != 0 {
+		return errno
+	}
+
+	return nil
+
+}
diff --git a/contrib/go/_std_1.18/src/internal/syscall/unix/at_sysnum_darwin.go b/contrib/go/_std_1.19/src/internal/syscall/unix/at_sysnum_darwin.go
index aaaaa4751c..aaaaa4751c 100644
--- a/contrib/go/_std_1.18/src/internal/syscall/unix/at_sysnum_darwin.go
+++ b/contrib/go/_std_1.19/src/internal/syscall/unix/at_sysnum_darwin.go
diff --git a/contrib/go/_std_1.18/src/internal/syscall/unix/at_sysnum_linux.go b/contrib/go/_std_1.19/src/internal/syscall/unix/at_sysnum_linux.go
index fa7cd75d42..fa7cd75d42 100644
--- a/contrib/go/_std_1.18/src/internal/syscall/unix/at_sysnum_linux.go
+++ b/contrib/go/_std_1.19/src/internal/syscall/unix/at_sysnum_linux.go
diff --git a/contrib/go/_std_1.18/src/internal/syscall/unix/at_sysnum_newfstatat_linux.go b/contrib/go/_std_1.19/src/internal/syscall/unix/at_sysnum_newfstatat_linux.go
index 76edf67522..76edf67522 100644
--- a/contrib/go/_std_1.18/src/internal/syscall/unix/at_sysnum_newfstatat_linux.go
+++ b/contrib/go/_std_1.19/src/internal/syscall/unix/at_sysnum_newfstatat_linux.go
diff --git a/contrib/go/_std_1.18/src/internal/syscall/unix/copy_file_range_linux.go b/contrib/go/_std_1.19/src/internal/syscall/unix/copy_file_range_linux.go
index cf0a279a7a..cf0a279a7a 100644
--- a/contrib/go/_std_1.18/src/internal/syscall/unix/copy_file_range_linux.go
+++ b/contrib/go/_std_1.19/src/internal/syscall/unix/copy_file_range_linux.go
diff --git a/contrib/go/_std_1.18/src/internal/syscall/unix/getentropy_darwin.go b/contrib/go/_std_1.19/src/internal/syscall/unix/getentropy_darwin.go
index 7bab1f27b0..7bab1f27b0 100644
--- a/contrib/go/_std_1.18/src/internal/syscall/unix/getentropy_darwin.go
+++ b/contrib/go/_std_1.19/src/internal/syscall/unix/getentropy_darwin.go
diff --git a/contrib/go/_std_1.18/src/internal/syscall/unix/getrandom.go b/contrib/go/_std_1.19/src/internal/syscall/unix/getrandom.go
index a6659331e4..a6659331e4 100644
--- a/contrib/go/_std_1.18/src/internal/syscall/unix/getrandom.go
+++ b/contrib/go/_std_1.19/src/internal/syscall/unix/getrandom.go
diff --git a/contrib/go/_std_1.18/src/internal/syscall/unix/getrandom_linux.go b/contrib/go/_std_1.19/src/internal/syscall/unix/getrandom_linux.go
index 8ccd8d328a..8ccd8d328a 100644
--- a/contrib/go/_std_1.18/src/internal/syscall/unix/getrandom_linux.go
+++ b/contrib/go/_std_1.19/src/internal/syscall/unix/getrandom_linux.go
diff --git a/contrib/go/_std_1.19/src/internal/syscall/unix/net.go b/contrib/go/_std_1.19/src/internal/syscall/unix/net.go
new file mode 100644
index 0000000000..5618d40ae0
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/syscall/unix/net.go
@@ -0,0 +1,44 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix
+
+package unix
+
+import (
+	"syscall"
+	_ "unsafe"
+)
+
+//go:linkname RecvfromInet4 syscall.recvfromInet4
+//go:noescape
+func RecvfromInet4(fd int, p []byte, flags int, from *syscall.SockaddrInet4) (int, error)
+
+//go:linkname RecvfromInet6 syscall.recvfromInet6
+//go:noescape
+func RecvfromInet6(fd int, p []byte, flags int, from *syscall.SockaddrInet6) (n int, err error)
+
+//go:linkname SendtoInet4 syscall.sendtoInet4
+//go:noescape
+func SendtoInet4(fd int, p []byte, flags int, to *syscall.SockaddrInet4) (err error)
+
+//go:linkname SendtoInet6 syscall.sendtoInet6
+//go:noescape
+func SendtoInet6(fd int, p []byte, flags int, to *syscall.SockaddrInet6) (err error)
+
+//go:linkname SendmsgNInet4 syscall.sendmsgNInet4
+//go:noescape
+func SendmsgNInet4(fd int, p, oob []byte, to *syscall.SockaddrInet4, flags int) (n int, err error)
+
+//go:linkname SendmsgNInet6 syscall.sendmsgNInet6
+//go:noescape
+func SendmsgNInet6(fd int, p, oob []byte, to *syscall.SockaddrInet6, flags int) (n int, err error)
+
+//go:linkname RecvmsgInet4 syscall.recvmsgInet4
+//go:noescape
+func RecvmsgInet4(fd int, p, oob []byte, flags int, from *syscall.SockaddrInet4) (n, oobn int, recvflags int, err error)
+
+//go:linkname RecvmsgInet6 syscall.recvmsgInet6
+//go:noescape
+func RecvmsgInet6(fd int, p, oob []byte, flags int, from *syscall.SockaddrInet6) (n, oobn int, recvflags int, err error)
diff --git a/contrib/go/_std_1.18/src/internal/syscall/unix/nonblocking.go b/contrib/go/_std_1.19/src/internal/syscall/unix/nonblocking.go
index 9e5f0fb4a2..9e5f0fb4a2 100644
--- a/contrib/go/_std_1.18/src/internal/syscall/unix/nonblocking.go
+++ b/contrib/go/_std_1.19/src/internal/syscall/unix/nonblocking.go
diff --git a/contrib/go/_std_1.19/src/internal/syscall/unix/nonblocking_libc.go b/contrib/go/_std_1.19/src/internal/syscall/unix/nonblocking_libc.go
new file mode 100644
index 0000000000..84940714c3
--- /dev/null
+++ b/contrib/go/_std_1.19/src/internal/syscall/unix/nonblocking_libc.go
@@ -0,0 +1,25 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build aix || darwin || solaris
+
+package unix
+
+import (
+	"syscall"
+	_ "unsafe" // for go:linkname
+)
+
+func IsNonblock(fd int) (nonblocking bool, err error) {
+	flag, e1 := fcntl(fd, syscall.F_GETFL, 0)
+	if e1 != nil {
+		return false, e1
+	}
+	return flag&syscall.O_NONBLOCK != 0, nil
+}
+
+// Implemented in the syscall package.
+//
+//go:linkname fcntl syscall.fcntl
+func fcntl(fd int, cmd int, arg int) (int, error)
diff --git a/contrib/go/_std_1.18/src/internal/syscall/unix/sysnum_linux_amd64.go b/contrib/go/_std_1.19/src/internal/syscall/unix/sysnum_linux_amd64.go
index ae5239ebfb..ae5239ebfb 100644
--- a/contrib/go/_std_1.18/src/internal/syscall/unix/sysnum_linux_amd64.go
+++ b/contrib/go/_std_1.19/src/internal/syscall/unix/sysnum_linux_amd64.go
diff --git a/contrib/go/_std_1.18/src/internal/testlog/exit.go b/contrib/go/_std_1.19/src/internal/testlog/exit.go
index e15defdb5b..e15defdb5b 100644
--- a/contrib/go/_std_1.18/src/internal/testlog/exit.go
+++ b/contrib/go/_std_1.19/src/internal/testlog/exit.go
diff --git a/contrib/go/_std_1.18/src/internal/testlog/log.go b/contrib/go/_std_1.19/src/internal/testlog/log.go
index 3c5f780ac4..3c5f780ac4 100644
--- a/contrib/go/_std_1.18/src/internal/testlog/log.go
+++ b/contrib/go/_std_1.19/src/internal/testlog/log.go
diff --git a/contrib/go/_std_1.18/src/internal/unsafeheader/unsafeheader.go b/contrib/go/_std_1.19/src/internal/unsafeheader/unsafeheader.go
index 6d092c629a..6d092c629a 100644
--- a/contrib/go/_std_1.18/src/internal/unsafeheader/unsafeheader.go
+++ b/contrib/go/_std_1.19/src/internal/unsafeheader/unsafeheader.go
diff --git a/contrib/go/_std_1.19/src/io/fs/fs.go b/contrib/go/_std_1.19/src/io/fs/fs.go
new file mode 100644
index 0000000000..4ce4d1a528
--- /dev/null
+++ b/contrib/go/_std_1.19/src/io/fs/fs.go
@@ -0,0 +1,258 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package fs defines basic interfaces to a file system.
+// A file system can be provided by the host operating system
+// but also by other packages.
+package fs
+
+import (
+	"internal/oserror"
+	"time"
+	"unicode/utf8"
+)
+
+// An FS provides access to a hierarchical file system.
+//
+// The FS interface is the minimum implementation required of the file system.
+// A file system may implement additional interfaces,
+// such as ReadFileFS, to provide additional or optimized functionality.
+type FS interface {
+	// Open opens the named file.
+	//
+	// When Open returns an error, it should be of type *PathError
+	// with the Op field set to "open", the Path field set to name,
+	// and the Err field describing the problem.
+	//
+	// Open should reject attempts to open names that do not satisfy
+	// ValidPath(name), returning a *PathError with Err set to
+	// ErrInvalid or ErrNotExist.
+	Open(name string) (File, error)
+}
+
+// ValidPath reports whether the given path name
+// is valid for use in a call to Open.
+//
+// Path names passed to open are UTF-8-encoded,
+// unrooted, slash-separated sequences of path elements, like “x/y/z”.
+// Path names must not contain an element that is “.” or “..” or the empty string,
+// except for the special case that the root directory is named “.”.
+// Paths must not start or end with a slash: “/x” and “x/” are invalid.
+//
+// Note that paths are slash-separated on all systems, even Windows.
+// Paths containing other characters such as backslash and colon
+// are accepted as valid, but those characters must never be
+// interpreted by an FS implementation as path element separators.
+func ValidPath(name string) bool {
+	if !utf8.ValidString(name) {
+		return false
+	}
+
+	if name == "." {
+		// special case
+		return true
+	}
+
+	// Iterate over elements in name, checking each.
+	for {
+		i := 0
+		for i < len(name) && name[i] != '/' {
+			i++
+		}
+		elem := name[:i]
+		if elem == "" || elem == "." || elem == ".." {
+			return false
+		}
+		if i == len(name) {
+			return true // reached clean ending
+		}
+		name = name[i+1:]
+	}
+}
+
+// A File provides access to a single file.
+// The File interface is the minimum implementation required of the file.
+// Directory files should also implement ReadDirFile.
+// A file may implement io.ReaderAt or io.Seeker as optimizations.
+type File interface {
+	Stat() (FileInfo, error)
+	Read([]byte) (int, error)
+	Close() error
+}
+
+// A DirEntry is an entry read from a directory
+// (using the ReadDir function or a ReadDirFile's ReadDir method).
+type DirEntry interface {
+	// Name returns the name of the file (or subdirectory) described by the entry.
+	// This name is only the final element of the path (the base name), not the entire path.
+	// For example, Name would return "hello.go" not "home/gopher/hello.go".
+	Name() string
+
+	// IsDir reports whether the entry describes a directory.
+	IsDir() bool
+
+	// Type returns the type bits for the entry.
+	// The type bits are a subset of the usual FileMode bits, those returned by the FileMode.Type method.
+	Type() FileMode
+
+	// Info returns the FileInfo for the file or subdirectory described by the entry.
+	// The returned FileInfo may be from the time of the original directory read
+	// or from the time of the call to Info. If the file has been removed or renamed
+	// since the directory read, Info may return an error satisfying errors.Is(err, ErrNotExist).
+	// If the entry denotes a symbolic link, Info reports the information about the link itself,
+	// not the link's target.
+	Info() (FileInfo, error)
+}
+
+// A ReadDirFile is a directory file whose entries can be read with the ReadDir method.
+// Every directory file should implement this interface.
+// (It is permissible for any file to implement this interface,
+// but if so ReadDir should return an error for non-directories.)
+type ReadDirFile interface {
+	File
+
+	// ReadDir reads the contents of the directory and returns
+	// a slice of up to n DirEntry values in directory order.
+	// Subsequent calls on the same file will yield further DirEntry values.
+	//
+	// If n > 0, ReadDir returns at most n DirEntry structures.
+	// In this case, if ReadDir returns an empty slice, it will return
+	// a non-nil error explaining why.
+	// At the end of a directory, the error is io.EOF.
+	// (ReadDir must return io.EOF itself, not an error wrapping io.EOF.)
+	//
+	// If n <= 0, ReadDir returns all the DirEntry values from the directory
+	// in a single slice. In this case, if ReadDir succeeds (reads all the way
+	// to the end of the directory), it returns the slice and a nil error.
+	// If it encounters an error before the end of the directory,
+	// ReadDir returns the DirEntry list read until that point and a non-nil error.
+	ReadDir(n int) ([]DirEntry, error)
+}
+
+// Generic file system errors.
+// Errors returned by file systems can be tested against these errors
+// using errors.Is.
+var (
+	ErrInvalid    = errInvalid()    // "invalid argument"
+	ErrPermission = errPermission() // "permission denied"
+	ErrExist      = errExist()      // "file already exists"
+	ErrNotExist   = errNotExist()   // "file does not exist"
+	ErrClosed     = errClosed()     // "file already closed"
+)
+
+func errInvalid() error    { return oserror.ErrInvalid }
+func errPermission() error { return oserror.ErrPermission }
+func errExist() error      { return oserror.ErrExist }
+func errNotExist() error   { return oserror.ErrNotExist }
+func errClosed() error     { return oserror.ErrClosed }
+
+// A FileInfo describes a file and is returned by Stat.
+type FileInfo interface {
+	Name() string       // base name of the file
+	Size() int64        // length in bytes for regular files; system-dependent for others
+	Mode() FileMode     // file mode bits
+	ModTime() time.Time // modification time
+	IsDir() bool        // abbreviation for Mode().IsDir()
+	Sys() any           // underlying data source (can return nil)
+}
+
+// A FileMode represents a file's mode and permission bits.
+// The bits have the same definition on all systems, so that
+// information about files can be moved from one system
+// to another portably. Not all bits apply to all systems.
+// The only required bit is ModeDir for directories.
+type FileMode uint32
+
+// The defined file mode bits are the most significant bits of the FileMode.
+// The nine least-significant bits are the standard Unix rwxrwxrwx permissions.
+// The values of these bits should be considered part of the public API and
+// may be used in wire protocols or disk representations: they must not be
+// changed, although new bits might be added.
+const (
+	// The single letters are the abbreviations
+	// used by the String method's formatting.
+	ModeDir        FileMode = 1 << (32 - 1 - iota) // d: is a directory
+	ModeAppend                                     // a: append-only
+	ModeExclusive                                  // l: exclusive use
+	ModeTemporary                                  // T: temporary file; Plan 9 only
+	ModeSymlink                                    // L: symbolic link
+	ModeDevice                                     // D: device file
+	ModeNamedPipe                                  // p: named pipe (FIFO)
+	ModeSocket                                     // S: Unix domain socket
+	ModeSetuid                                     // u: setuid
+	ModeSetgid                                     // g: setgid
+	ModeCharDevice                                 // c: Unix character device, when ModeDevice is set
+	ModeSticky                                     // t: sticky
+	ModeIrregular                                  // ?: non-regular file; nothing else is known about this file
+
+	// Mask for the type bits. For regular files, none will be set.
+	ModeType = ModeDir | ModeSymlink | ModeNamedPipe | ModeSocket | ModeDevice | ModeCharDevice | ModeIrregular
+
+	ModePerm FileMode = 0777 // Unix permission bits
+)
+
+func (m FileMode) String() string {
+	const str = "dalTLDpSugct?"
+	var buf [32]byte // Mode is uint32.
+	w := 0
+	for i, c := range str {
+		if m&(1<<uint(32-1-i)) != 0 {
+			buf[w] = byte(c)
+			w++
+		}
+	}
+	if w == 0 {
+		buf[w] = '-'
+		w++
+	}
+	const rwx = "rwxrwxrwx"
+	for i, c := range rwx {
+		if m&(1<<uint(9-1-i)) != 0 {
+			buf[w] = byte(c)
+		} else {
+			buf[w] = '-'
+		}
+		w++
+	}
+	return string(buf[:w])
+}
+
+// IsDir reports whether m describes a directory.
+// That is, it tests for the ModeDir bit being set in m.
+func (m FileMode) IsDir() bool {
+	return m&ModeDir != 0
+}
+
+// IsRegular reports whether m describes a regular file.
+// That is, it tests that no mode type bits are set.
+func (m FileMode) IsRegular() bool {
+	return m&ModeType == 0
+}
+
+// Perm returns the Unix permission bits in m (m & ModePerm).
+func (m FileMode) Perm() FileMode {
+	return m & ModePerm
+}
+
+// Type returns type bits in m (m & ModeType).
+func (m FileMode) Type() FileMode {
+	return m & ModeType
+}
+
+// PathError records an error and the operation and file path that caused it.
+type PathError struct {
+	Op   string
+	Path string
+	Err  error
+}
+
+func (e *PathError) Error() string { return e.Op + " " + e.Path + ": " + e.Err.Error() }
+
+func (e *PathError) Unwrap() error { return e.Err }
+
+// Timeout reports whether this error represents a timeout.
+func (e *PathError) Timeout() bool {
+	t, ok := e.Err.(interface{ Timeout() bool })
+	return ok && t.Timeout()
+}
diff --git a/contrib/go/_std_1.18/src/io/fs/glob.go b/contrib/go/_std_1.19/src/io/fs/glob.go
index 0e529cd05d..0e529cd05d 100644
--- a/contrib/go/_std_1.18/src/io/fs/glob.go
+++ b/contrib/go/_std_1.19/src/io/fs/glob.go
diff --git a/contrib/go/_std_1.18/src/io/fs/readdir.go b/contrib/go/_std_1.19/src/io/fs/readdir.go
index 2b10ddb0a3..2b10ddb0a3 100644
--- a/contrib/go/_std_1.18/src/io/fs/readdir.go
+++ b/contrib/go/_std_1.19/src/io/fs/readdir.go
diff --git a/contrib/go/_std_1.18/src/io/fs/readfile.go b/contrib/go/_std_1.19/src/io/fs/readfile.go
index d3c181c0a9..d3c181c0a9 100644
--- a/contrib/go/_std_1.18/src/io/fs/readfile.go
+++ b/contrib/go/_std_1.19/src/io/fs/readfile.go
diff --git a/contrib/go/_std_1.18/src/io/fs/stat.go b/contrib/go/_std_1.19/src/io/fs/stat.go
index 735a6e3281..735a6e3281 100644
--- a/contrib/go/_std_1.18/src/io/fs/stat.go
+++ b/contrib/go/_std_1.19/src/io/fs/stat.go
diff --git a/contrib/go/_std_1.18/src/io/fs/sub.go b/contrib/go/_std_1.19/src/io/fs/sub.go
index ae20e030a9..ae20e030a9 100644
--- a/contrib/go/_std_1.18/src/io/fs/sub.go
+++ b/contrib/go/_std_1.19/src/io/fs/sub.go
diff --git a/contrib/go/_std_1.19/src/io/fs/walk.go b/contrib/go/_std_1.19/src/io/fs/walk.go
new file mode 100644
index 0000000000..37800794a2
--- /dev/null
+++ b/contrib/go/_std_1.19/src/io/fs/walk.go
@@ -0,0 +1,129 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package fs
+
+import (
+	"errors"
+	"path"
+)
+
+// SkipDir is used as a return value from WalkDirFuncs to indicate that
+// the directory named in the call is to be skipped. It is not returned
+// as an error by any function.
+var SkipDir = errors.New("skip this directory")
+
+// WalkDirFunc is the type of the function called by WalkDir to visit
+// each file or directory.
+//
+// The path argument contains the argument to WalkDir as a prefix.
+// That is, if WalkDir is called with root argument "dir" and finds a file
+// named "a" in that directory, the walk function will be called with
+// argument "dir/a".
+//
+// The d argument is the fs.DirEntry for the named path.
+//
+// The error result returned by the function controls how WalkDir
+// continues. If the function returns the special value SkipDir, WalkDir
+// skips the current directory (path if d.IsDir() is true, otherwise
+// path's parent directory). Otherwise, if the function returns a non-nil
+// error, WalkDir stops entirely and returns that error.
+//
+// The err argument reports an error related to path, signaling that
+// WalkDir will not walk into that directory. The function can decide how
+// to handle that error; as described earlier, returning the error will
+// cause WalkDir to stop walking the entire tree.
+//
+// WalkDir calls the function with a non-nil err argument in two cases.
+//
+// First, if the initial fs.Stat on the root directory fails, WalkDir
+// calls the function with path set to root, d set to nil, and err set to
+// the error from fs.Stat.
+//
+// Second, if a directory's ReadDir method fails, WalkDir calls the
+// function with path set to the directory's path, d set to an
+// fs.DirEntry describing the directory, and err set to the error from
+// ReadDir. In this second case, the function is called twice with the
+// path of the directory: the first call is before the directory read is
+// attempted and has err set to nil, giving the function a chance to
+// return SkipDir and avoid the ReadDir entirely. The second call is
+// after a failed ReadDir and reports the error from ReadDir.
+// (If ReadDir succeeds, there is no second call.)
+//
+// The differences between WalkDirFunc compared to filepath.WalkFunc are:
+//
+//   - The second argument has type fs.DirEntry instead of fs.FileInfo.
+//   - The function is called before reading a directory, to allow SkipDir
+//     to bypass the directory read entirely.
+//   - If a directory read fails, the function is called a second time
+//     for that directory to report the error.
+type WalkDirFunc func(path string, d DirEntry, err error) error
+
+// walkDir recursively descends path, calling walkDirFn.
+func walkDir(fsys FS, name string, d DirEntry, walkDirFn WalkDirFunc) error {
+	if err := walkDirFn(name, d, nil); err != nil || !d.IsDir() {
+		if err == SkipDir && d.IsDir() {
+			// Successfully skipped directory.
+			err = nil
+		}
+		return err
+	}
+
+	dirs, err := ReadDir(fsys, name)
+	if err != nil {
+		// Second call, to report ReadDir error.
+		err = walkDirFn(name, d, err)
+		if err != nil {
+			if err == SkipDir && d.IsDir() {
+				err = nil
+			}
+			return err
+		}
+	}
+
+	for _, d1 := range dirs {
+		name1 := path.Join(name, d1.Name())
+		if err := walkDir(fsys, name1, d1, walkDirFn); err != nil {
+			if err == SkipDir {
+				break
+			}
+			return err
+		}
+	}
+	return nil
+}
+
+// WalkDir walks the file tree rooted at root, calling fn for each file or
+// directory in the tree, including root.
+//
+// All errors that arise visiting files and directories are filtered by fn:
+// see the fs.WalkDirFunc documentation for details.
+//
+// The files are walked in lexical order, which makes the output deterministic
+// but requires WalkDir to read an entire directory into memory before proceeding
+// to walk that directory.
+//
+// WalkDir does not follow symbolic links found in directories,
+// but if root itself is a symbolic link, its target will be walked.
+func WalkDir(fsys FS, root string, fn WalkDirFunc) error {
+	info, err := Stat(fsys, root)
+	if err != nil {
+		err = fn(root, nil, err)
+	} else {
+		err = walkDir(fsys, root, &statDirEntry{info}, fn)
+	}
+	if err == SkipDir {
+		return nil
+	}
+	return err
+}
+
+type statDirEntry struct {
+	info FileInfo
+}
+
+func (d *statDirEntry) Name() string            { return d.info.Name() }
+func (d *statDirEntry) IsDir() bool             { return d.info.IsDir() }
+func (d *statDirEntry) Type() FileMode          { return d.info.Mode().Type() }
+func (d *statDirEntry) Info() (FileInfo, error) { return d.info, nil }
diff --git a/contrib/go/_std_1.19/src/io/io.go b/contrib/go/_std_1.19/src/io/io.go
new file mode 100644
index 0000000000..9d4c0d2506
--- /dev/null
+++ b/contrib/go/_std_1.19/src/io/io.go
@@ -0,0 +1,670 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package io provides basic interfaces to I/O primitives.
+// Its primary job is to wrap existing implementations of such primitives,
+// such as those in package os, into shared public interfaces that
+// abstract the functionality, plus some other related primitives.
+//
+// Because these interfaces and primitives wrap lower-level operations with
+// various implementations, unless otherwise informed clients should not
+// assume they are safe for parallel execution.
+package io
+
+import (
+	"errors"
+	"sync"
+)
+
+// Seek whence values.
+const (
+	SeekStart   = 0 // seek relative to the origin of the file
+	SeekCurrent = 1 // seek relative to the current offset
+	SeekEnd     = 2 // seek relative to the end
+)
+
+// ErrShortWrite means that a write accepted fewer bytes than requested
+// but failed to return an explicit error.
+var ErrShortWrite = errors.New("short write")
+
+// errInvalidWrite means that a write returned an impossible count.
+var errInvalidWrite = errors.New("invalid write result")
+
+// ErrShortBuffer means that a read required a longer buffer than was provided.
+var ErrShortBuffer = errors.New("short buffer")
+
+// EOF is the error returned by Read when no more input is available.
+// (Read must return EOF itself, not an error wrapping EOF,
+// because callers will test for EOF using ==.)
+// Functions should return EOF only to signal a graceful end of input.
+// If the EOF occurs unexpectedly in a structured data stream,
+// the appropriate error is either ErrUnexpectedEOF or some other error
+// giving more detail.
+var EOF = errors.New("EOF")
+
+// ErrUnexpectedEOF means that EOF was encountered in the
+// middle of reading a fixed-size block or data structure.
+var ErrUnexpectedEOF = errors.New("unexpected EOF")
+
+// ErrNoProgress is returned by some clients of a Reader when
+// many calls to Read have failed to return any data or error,
+// usually the sign of a broken Reader implementation.
+var ErrNoProgress = errors.New("multiple Read calls return no data or error")
+
+// Reader is the interface that wraps the basic Read method.
+//
+// Read reads up to len(p) bytes into p. It returns the number of bytes
+// read (0 <= n <= len(p)) and any error encountered. Even if Read
+// returns n < len(p), it may use all of p as scratch space during the call.
+// If some data is available but not len(p) bytes, Read conventionally
+// returns what is available instead of waiting for more.
+//
+// When Read encounters an error or end-of-file condition after
+// successfully reading n > 0 bytes, it returns the number of
+// bytes read. It may return the (non-nil) error from the same call
+// or return the error (and n == 0) from a subsequent call.
+// An instance of this general case is that a Reader returning
+// a non-zero number of bytes at the end of the input stream may
+// return either err == EOF or err == nil. The next Read should
+// return 0, EOF.
+//
+// Callers should always process the n > 0 bytes returned before
+// considering the error err. Doing so correctly handles I/O errors
+// that happen after reading some bytes and also both of the
+// allowed EOF behaviors.
+//
+// Implementations of Read are discouraged from returning a
+// zero byte count with a nil error, except when len(p) == 0.
+// Callers should treat a return of 0 and nil as indicating that
+// nothing happened; in particular it does not indicate EOF.
+//
+// Implementations must not retain p.
+type Reader interface {
+	Read(p []byte) (n int, err error)
+}
+
+// Writer is the interface that wraps the basic Write method.
+//
+// Write writes len(p) bytes from p to the underlying data stream.
+// It returns the number of bytes written from p (0 <= n <= len(p))
+// and any error encountered that caused the write to stop early.
+// Write must return a non-nil error if it returns n < len(p).
+// Write must not modify the slice data, even temporarily.
+//
+// Implementations must not retain p.
+type Writer interface {
+	Write(p []byte) (n int, err error)
+}
+
+// Closer is the interface that wraps the basic Close method.
+//
+// The behavior of Close after the first call is undefined.
+// Specific implementations may document their own behavior.
+type Closer interface {
+	Close() error
+}
+
+// Seeker is the interface that wraps the basic Seek method.
+//
+// Seek sets the offset for the next Read or Write to offset,
+// interpreted according to whence:
+// SeekStart means relative to the start of the file,
+// SeekCurrent means relative to the current offset, and
+// SeekEnd means relative to the end
+// (for example, offset = -2 specifies the penultimate byte of the file).
+// Seek returns the new offset relative to the start of the
+// file or an error, if any.
+//
+// Seeking to an offset before the start of the file is an error.
+// Seeking to any positive offset may be allowed, but if the new offset exceeds
+// the size of the underlying object the behavior of subsequent I/O operations
+// is implementation-dependent.
+type Seeker interface {
+	Seek(offset int64, whence int) (int64, error)
+}
+
+// ReadWriter is the interface that groups the basic Read and Write methods.
+type ReadWriter interface {
+	Reader
+	Writer
+}
+
+// ReadCloser is the interface that groups the basic Read and Close methods.
+type ReadCloser interface {
+	Reader
+	Closer
+}
+
+// WriteCloser is the interface that groups the basic Write and Close methods.
+type WriteCloser interface {
+	Writer
+	Closer
+}
+
+// ReadWriteCloser is the interface that groups the basic Read, Write and Close methods.
+type ReadWriteCloser interface {
+	Reader
+	Writer
+	Closer
+}
+
+// ReadSeeker is the interface that groups the basic Read and Seek methods.
+type ReadSeeker interface {
+	Reader
+	Seeker
+}
+
+// ReadSeekCloser is the interface that groups the basic Read, Seek and Close
+// methods.
+type ReadSeekCloser interface {
+	Reader
+	Seeker
+	Closer
+}
+
+// WriteSeeker is the interface that groups the basic Write and Seek methods.
+type WriteSeeker interface {
+	Writer
+	Seeker
+}
+
+// ReadWriteSeeker is the interface that groups the basic Read, Write and Seek methods.
+type ReadWriteSeeker interface {
+	Reader
+	Writer
+	Seeker
+}
+
+// ReaderFrom is the interface that wraps the ReadFrom method.
+//
+// ReadFrom reads data from r until EOF or error.
+// The return value n is the number of bytes read.
+// Any error except EOF encountered during the read is also returned.
+//
+// The Copy function uses ReaderFrom if available.
+type ReaderFrom interface {
+	ReadFrom(r Reader) (n int64, err error)
+}
+
+// WriterTo is the interface that wraps the WriteTo method.
+//
+// WriteTo writes data to w until there's no more data to write or
+// when an error occurs. The return value n is the number of bytes
+// written. Any error encountered during the write is also returned.
+//
+// The Copy function uses WriterTo if available.
+type WriterTo interface {
+	WriteTo(w Writer) (n int64, err error)
+}
+
+// ReaderAt is the interface that wraps the basic ReadAt method.
+//
+// ReadAt reads len(p) bytes into p starting at offset off in the
+// underlying input source. It returns the number of bytes
+// read (0 <= n <= len(p)) and any error encountered.
+//
+// When ReadAt returns n < len(p), it returns a non-nil error
+// explaining why more bytes were not returned. In this respect,
+// ReadAt is stricter than Read.
+//
+// Even if ReadAt returns n < len(p), it may use all of p as scratch
+// space during the call. If some data is available but not len(p) bytes,
+// ReadAt blocks until either all the data is available or an error occurs.
+// In this respect ReadAt is different from Read.
+//
+// If the n = len(p) bytes returned by ReadAt are at the end of the
+// input source, ReadAt may return either err == EOF or err == nil.
+//
+// If ReadAt is reading from an input source with a seek offset,
+// ReadAt should not affect nor be affected by the underlying
+// seek offset.
+//
+// Clients of ReadAt can execute parallel ReadAt calls on the
+// same input source.
+//
+// Implementations must not retain p.
+type ReaderAt interface {
+	ReadAt(p []byte, off int64) (n int, err error)
+}
+
+// WriterAt is the interface that wraps the basic WriteAt method.
+//
+// WriteAt writes len(p) bytes from p to the underlying data stream
+// at offset off. It returns the number of bytes written from p (0 <= n <= len(p))
+// and any error encountered that caused the write to stop early.
+// WriteAt must return a non-nil error if it returns n < len(p).
+//
+// If WriteAt is writing to a destination with a seek offset,
+// WriteAt should not affect nor be affected by the underlying
+// seek offset.
+//
+// Clients of WriteAt can execute parallel WriteAt calls on the same
+// destination if the ranges do not overlap.
+//
+// Implementations must not retain p.
+type WriterAt interface {
+	WriteAt(p []byte, off int64) (n int, err error)
+}
+
+// ByteReader is the interface that wraps the ReadByte method.
+//
+// ReadByte reads and returns the next byte from the input or
+// any error encountered. If ReadByte returns an error, no input
+// byte was consumed, and the returned byte value is undefined.
+//
+// ReadByte provides an efficient interface for byte-at-time
+// processing. A Reader that does not implement  ByteReader
+// can be wrapped using bufio.NewReader to add this method.
+type ByteReader interface {
+	ReadByte() (byte, error)
+}
+
+// ByteScanner is the interface that adds the UnreadByte method to the
+// basic ReadByte method.
+//
+// UnreadByte causes the next call to ReadByte to return the last byte read.
+// If the last operation was not a successful call to ReadByte, UnreadByte may
+// return an error, unread the last byte read (or the byte prior to the
+// last-unread byte), or (in implementations that support the Seeker interface)
+// seek to one byte before the current offset.
+type ByteScanner interface {
+	ByteReader
+	UnreadByte() error
+}
+
+// ByteWriter is the interface that wraps the WriteByte method.
+type ByteWriter interface {
+	WriteByte(c byte) error
+}
+
+// RuneReader is the interface that wraps the ReadRune method.
+//
+// ReadRune reads a single encoded Unicode character
+// and returns the rune and its size in bytes. If no character is
+// available, err will be set.
+type RuneReader interface {
+	ReadRune() (r rune, size int, err error)
+}
+
+// RuneScanner is the interface that adds the UnreadRune method to the
+// basic ReadRune method.
+//
+// UnreadRune causes the next call to ReadRune to return the last rune read.
+// If the last operation was not a successful call to ReadRune, UnreadRune may
+// return an error, unread the last rune read (or the rune prior to the
+// last-unread rune), or (in implementations that support the Seeker interface)
+// seek to the start of the rune before the current offset.
+type RuneScanner interface {
+	RuneReader
+	UnreadRune() error
+}
+
+// StringWriter is the interface that wraps the WriteString method.
+type StringWriter interface {
+	WriteString(s string) (n int, err error)
+}
+
+// WriteString writes the contents of the string s to w, which accepts a slice of bytes.
+// If w implements StringWriter, its WriteString method is invoked directly.
+// Otherwise, w.Write is called exactly once.
+func WriteString(w Writer, s string) (n int, err error) {
+	if sw, ok := w.(StringWriter); ok {
+		return sw.WriteString(s)
+	}
+	return w.Write([]byte(s))
+}
+
+// ReadAtLeast reads from r into buf until it has read at least min bytes.
+// It returns the number of bytes copied and an error if fewer bytes were read.
+// The error is EOF only if no bytes were read.
+// If an EOF happens after reading fewer than min bytes,
+// ReadAtLeast returns ErrUnexpectedEOF.
+// If min is greater than the length of buf, ReadAtLeast returns ErrShortBuffer.
+// On return, n >= min if and only if err == nil.
+// If r returns an error having read at least min bytes, the error is dropped.
+func ReadAtLeast(r Reader, buf []byte, min int) (n int, err error) {
+	if len(buf) < min {
+		return 0, ErrShortBuffer
+	}
+	for n < min && err == nil {
+		var nn int
+		nn, err = r.Read(buf[n:])
+		n += nn
+	}
+	if n >= min {
+		err = nil
+	} else if n > 0 && err == EOF {
+		err = ErrUnexpectedEOF
+	}
+	return
+}
+
+// ReadFull reads exactly len(buf) bytes from r into buf.
+// It returns the number of bytes copied and an error if fewer bytes were read.
+// The error is EOF only if no bytes were read.
+// If an EOF happens after reading some but not all the bytes,
+// ReadFull returns ErrUnexpectedEOF.
+// On return, n == len(buf) if and only if err == nil.
+// If r returns an error having read at least len(buf) bytes, the error is dropped.
+func ReadFull(r Reader, buf []byte) (n int, err error) {
+	return ReadAtLeast(r, buf, len(buf))
+}
+
+// CopyN copies n bytes (or until an error) from src to dst.
+// It returns the number of bytes copied and the earliest
+// error encountered while copying.
+// On return, written == n if and only if err == nil.
+//
+// If dst implements the ReaderFrom interface,
+// the copy is implemented using it.
+func CopyN(dst Writer, src Reader, n int64) (written int64, err error) {
+	written, err = Copy(dst, LimitReader(src, n))
+	if written == n {
+		return n, nil
+	}
+	if written < n && err == nil {
+		// src stopped early; must have been EOF.
+		err = EOF
+	}
+	return
+}
+
+// Copy copies from src to dst until either EOF is reached
+// on src or an error occurs. It returns the number of bytes
+// copied and the first error encountered while copying, if any.
+//
+// A successful Copy returns err == nil, not err == EOF.
+// Because Copy is defined to read from src until EOF, it does
+// not treat an EOF from Read as an error to be reported.
+//
+// If src implements the WriterTo interface,
+// the copy is implemented by calling src.WriteTo(dst).
+// Otherwise, if dst implements the ReaderFrom interface,
+// the copy is implemented by calling dst.ReadFrom(src).
+func Copy(dst Writer, src Reader) (written int64, err error) {
+	return copyBuffer(dst, src, nil)
+}
+
+// CopyBuffer is identical to Copy except that it stages through the
+// provided buffer (if one is required) rather than allocating a
+// temporary one. If buf is nil, one is allocated; otherwise if it has
+// zero length, CopyBuffer panics.
+//
+// If either src implements WriterTo or dst implements ReaderFrom,
+// buf will not be used to perform the copy.
+func CopyBuffer(dst Writer, src Reader, buf []byte) (written int64, err error) {
+	if buf != nil && len(buf) == 0 {
+		panic("empty buffer in CopyBuffer")
+	}
+	return copyBuffer(dst, src, buf)
+}
+
+// copyBuffer is the actual implementation of Copy and CopyBuffer.
+// if buf is nil, one is allocated.
+func copyBuffer(dst Writer, src Reader, buf []byte) (written int64, err error) {
+	// If the reader has a WriteTo method, use it to do the copy.
+	// Avoids an allocation and a copy.
+	if wt, ok := src.(WriterTo); ok {
+		return wt.WriteTo(dst)
+	}
+	// Similarly, if the writer has a ReadFrom method, use it to do the copy.
+	if rt, ok := dst.(ReaderFrom); ok {
+		return rt.ReadFrom(src)
+	}
+	if buf == nil {
+		size := 32 * 1024
+		if l, ok := src.(*LimitedReader); ok && int64(size) > l.N {
+			if l.N < 1 {
+				size = 1
+			} else {
+				size = int(l.N)
+			}
+		}
+		buf = make([]byte, size)
+	}
+	for {
+		nr, er := src.Read(buf)
+		if nr > 0 {
+			nw, ew := dst.Write(buf[0:nr])
+			if nw < 0 || nr < nw {
+				nw = 0
+				if ew == nil {
+					ew = errInvalidWrite
+				}
+			}
+			written += int64(nw)
+			if ew != nil {
+				err = ew
+				break
+			}
+			if nr != nw {
+				err = ErrShortWrite
+				break
+			}
+		}
+		if er != nil {
+			if er != EOF {
+				err = er
+			}
+			break
+		}
+	}
+	return written, err
+}
+
+// LimitReader returns a Reader that reads from r
+// but stops with EOF after n bytes.
+// The underlying implementation is a *LimitedReader.
+func LimitReader(r Reader, n int64) Reader { return &LimitedReader{r, n} }
+
+// A LimitedReader reads from R but limits the amount of
+// data returned to just N bytes. Each call to Read
+// updates N to reflect the new amount remaining.
+// Read returns EOF when N <= 0 or when the underlying R returns EOF.
+type LimitedReader struct {
+	R Reader // underlying reader
+	N int64  // max bytes remaining
+}
+
+func (l *LimitedReader) Read(p []byte) (n int, err error) {
+	if l.N <= 0 {
+		return 0, EOF
+	}
+	if int64(len(p)) > l.N {
+		p = p[0:l.N]
+	}
+	n, err = l.R.Read(p)
+	l.N -= int64(n)
+	return
+}
+
+// NewSectionReader returns a SectionReader that reads from r
+// starting at offset off and stops with EOF after n bytes.
+func NewSectionReader(r ReaderAt, off int64, n int64) *SectionReader {
+	var remaining int64
+	const maxint64 = 1<<63 - 1
+	if off <= maxint64-n {
+		remaining = n + off
+	} else {
+		// Overflow, with no way to return error.
+		// Assume we can read up to an offset of 1<<63 - 1.
+		remaining = maxint64
+	}
+	return &SectionReader{r, off, off, remaining}
+}
+
+// SectionReader implements Read, Seek, and ReadAt on a section
+// of an underlying ReaderAt.
+type SectionReader struct {
+	r     ReaderAt
+	base  int64
+	off   int64
+	limit int64
+}
+
+func (s *SectionReader) Read(p []byte) (n int, err error) {
+	if s.off >= s.limit {
+		return 0, EOF
+	}
+	if max := s.limit - s.off; int64(len(p)) > max {
+		p = p[0:max]
+	}
+	n, err = s.r.ReadAt(p, s.off)
+	s.off += int64(n)
+	return
+}
+
+var errWhence = errors.New("Seek: invalid whence")
+var errOffset = errors.New("Seek: invalid offset")
+
+func (s *SectionReader) Seek(offset int64, whence int) (int64, error) {
+	switch whence {
+	default:
+		return 0, errWhence
+	case SeekStart:
+		offset += s.base
+	case SeekCurrent:
+		offset += s.off
+	case SeekEnd:
+		offset += s.limit
+	}
+	if offset < s.base {
+		return 0, errOffset
+	}
+	s.off = offset
+	return offset - s.base, nil
+}
+
+func (s *SectionReader) ReadAt(p []byte, off int64) (n int, err error) {
+	if off < 0 || off >= s.limit-s.base {
+		return 0, EOF
+	}
+	off += s.base
+	if max := s.limit - off; int64(len(p)) > max {
+		p = p[0:max]
+		n, err = s.r.ReadAt(p, off)
+		if err == nil {
+			err = EOF
+		}
+		return n, err
+	}
+	return s.r.ReadAt(p, off)
+}
+
+// Size returns the size of the section in bytes.
+func (s *SectionReader) Size() int64 { return s.limit - s.base }
+
+// TeeReader returns a Reader that writes to w what it reads from r.
+// All reads from r performed through it are matched with
+// corresponding writes to w. There is no internal buffering -
+// the write must complete before the read completes.
+// Any error encountered while writing is reported as a read error.
+func TeeReader(r Reader, w Writer) Reader {
+	return &teeReader{r, w}
+}
+
+type teeReader struct {
+	r Reader
+	w Writer
+}
+
+func (t *teeReader) Read(p []byte) (n int, err error) {
+	n, err = t.r.Read(p)
+	if n > 0 {
+		if n, err := t.w.Write(p[:n]); err != nil {
+			return n, err
+		}
+	}
+	return
+}
+
+// Discard is a Writer on which all Write calls succeed
+// without doing anything.
+var Discard Writer = discard{}
+
+type discard struct{}
+
+// discard implements ReaderFrom as an optimization so Copy to
+// io.Discard can avoid doing unnecessary work.
+var _ ReaderFrom = discard{}
+
+func (discard) Write(p []byte) (int, error) {
+	return len(p), nil
+}
+
+func (discard) WriteString(s string) (int, error) {
+	return len(s), nil
+}
+
+var blackHolePool = sync.Pool{
+	New: func() any {
+		b := make([]byte, 8192)
+		return &b
+	},
+}
+
+func (discard) ReadFrom(r Reader) (n int64, err error) {
+	bufp := blackHolePool.Get().(*[]byte)
+	readSize := 0
+	for {
+		readSize, err = r.Read(*bufp)
+		n += int64(readSize)
+		if err != nil {
+			blackHolePool.Put(bufp)
+			if err == EOF {
+				return n, nil
+			}
+			return
+		}
+	}
+}
+
+// NopCloser returns a ReadCloser with a no-op Close method wrapping
+// the provided Reader r.
+// If r implements WriterTo, the returned ReadCloser will implement WriterTo
+// by forwarding calls to r.
+func NopCloser(r Reader) ReadCloser {
+	if _, ok := r.(WriterTo); ok {
+		return nopCloserWriterTo{r}
+	}
+	return nopCloser{r}
+}
+
+type nopCloser struct {
+	Reader
+}
+
+func (nopCloser) Close() error { return nil }
+
+type nopCloserWriterTo struct {
+	Reader
+}
+
+func (nopCloserWriterTo) Close() error { return nil }
+
+func (c nopCloserWriterTo) WriteTo(w Writer) (n int64, err error) {
+	return c.Reader.(WriterTo).WriteTo(w)
+}
+
+// ReadAll reads from r until an error or EOF and returns the data it read.
+// A successful call returns err == nil, not err == EOF. Because ReadAll is
+// defined to read from src until EOF, it does not treat an EOF from Read
+// as an error to be reported.
+func ReadAll(r Reader) ([]byte, error) {
+	b := make([]byte, 0, 512)
+	for {
+		if len(b) == cap(b) {
+			// Add more capacity (let append pick how much).
+			b = append(b, 0)[:len(b)]
+		}
+		n, err := r.Read(b[len(b):cap(b)])
+		b = b[:len(b)+n]
+		if err != nil {
+			if err == EOF {
+				err = nil
+			}
+			return b, err
+		}
+	}
+}
diff --git a/contrib/go/_std_1.19/src/io/ioutil/ioutil.go b/contrib/go/_std_1.19/src/io/ioutil/ioutil.go
new file mode 100644
index 0000000000..6a1d69172c
--- /dev/null
+++ b/contrib/go/_std_1.19/src/io/ioutil/ioutil.go
@@ -0,0 +1,95 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package ioutil implements some I/O utility functions.
+//
+// Deprecated: As of Go 1.16, the same functionality is now provided
+// by package io or package os, and those implementations
+// should be preferred in new code.
+// See the specific function documentation for details.
+package ioutil
+
+import (
+	"io"
+	"io/fs"
+	"os"
+	"sort"
+)
+
+// ReadAll reads from r until an error or EOF and returns the data it read.
+// A successful call returns err == nil, not err == EOF. Because ReadAll is
+// defined to read from src until EOF, it does not treat an EOF from Read
+// as an error to be reported.
+//
+// Deprecated: As of Go 1.16, this function simply calls io.ReadAll.
+func ReadAll(r io.Reader) ([]byte, error) {
+	return io.ReadAll(r)
+}
+
+// ReadFile reads the file named by filename and returns the contents.
+// A successful call returns err == nil, not err == EOF. Because ReadFile
+// reads the whole file, it does not treat an EOF from Read as an error
+// to be reported.
+//
+// Deprecated: As of Go 1.16, this function simply calls os.ReadFile.
+func ReadFile(filename string) ([]byte, error) {
+	return os.ReadFile(filename)
+}
+
+// WriteFile writes data to a file named by filename.
+// If the file does not exist, WriteFile creates it with permissions perm
+// (before umask); otherwise WriteFile truncates it before writing, without changing permissions.
+//
+// Deprecated: As of Go 1.16, this function simply calls os.WriteFile.
+func WriteFile(filename string, data []byte, perm fs.FileMode) error {
+	return os.WriteFile(filename, data, perm)
+}
+
+// ReadDir reads the directory named by dirname and returns
+// a list of fs.FileInfo for the directory's contents,
+// sorted by filename. If an error occurs reading the directory,
+// ReadDir returns no directory entries along with the error.
+//
+// Deprecated: As of Go 1.16, os.ReadDir is a more efficient and correct choice:
+// it returns a list of fs.DirEntry instead of fs.FileInfo,
+// and it returns partial results in the case of an error
+// midway through reading a directory.
+//
+// If you must continue obtaining a list of fs.FileInfo, you still can:
+//
+//	entries, err := os.ReadDir(dirname)
+//	if err != nil { ... }
+//	infos := make([]fs.FileInfo, 0, len(entries))
+//	for _, entry := range entries {
+//		info, err := entry.Info()
+//		if err != nil { ... }
+//		infos = append(infos, info)
+//	}
+func ReadDir(dirname string) ([]fs.FileInfo, error) {
+	f, err := os.Open(dirname)
+	if err != nil {
+		return nil, err
+	}
+	list, err := f.Readdir(-1)
+	f.Close()
+	if err != nil {
+		return nil, err
+	}
+	sort.Slice(list, func(i, j int) bool { return list[i].Name() < list[j].Name() })
+	return list, nil
+}
+
+// NopCloser returns a ReadCloser with a no-op Close method wrapping
+// the provided Reader r.
+//
+// Deprecated: As of Go 1.16, this function simply calls io.NopCloser.
+func NopCloser(r io.Reader) io.ReadCloser {
+	return io.NopCloser(r)
+}
+
+// Discard is an io.Writer on which all Write calls succeed
+// without doing anything.
+//
+// Deprecated: As of Go 1.16, this value is simply io.Discard.
+var Discard io.Writer = io.Discard
diff --git a/contrib/go/_std_1.19/src/io/ioutil/tempfile.go b/contrib/go/_std_1.19/src/io/ioutil/tempfile.go
new file mode 100644
index 0000000000..0561ad5a27
--- /dev/null
+++ b/contrib/go/_std_1.19/src/io/ioutil/tempfile.go
@@ -0,0 +1,41 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ioutil
+
+import (
+	"os"
+)
+
+// TempFile creates a new temporary file in the directory dir,
+// opens the file for reading and writing, and returns the resulting *os.File.
+// The filename is generated by taking pattern and adding a random
+// string to the end. If pattern includes a "*", the random string
+// replaces the last "*".
+// If dir is the empty string, TempFile uses the default directory
+// for temporary files (see os.TempDir).
+// Multiple programs calling TempFile simultaneously
+// will not choose the same file. The caller can use f.Name()
+// to find the pathname of the file. It is the caller's responsibility
+// to remove the file when no longer needed.
+//
+// Deprecated: As of Go 1.17, this function simply calls os.CreateTemp.
+func TempFile(dir, pattern string) (f *os.File, err error) {
+	return os.CreateTemp(dir, pattern)
+}
+
+// TempDir creates a new temporary directory in the directory dir.
+// The directory name is generated by taking pattern and applying a
+// random string to the end. If pattern includes a "*", the random string
+// replaces the last "*". TempDir returns the name of the new directory.
+// If dir is the empty string, TempDir uses the
+// default directory for temporary files (see os.TempDir).
+// Multiple programs calling TempDir simultaneously
+// will not choose the same directory. It is the caller's responsibility
+// to remove the directory when no longer needed.
+//
+// Deprecated: As of Go 1.17, this function simply calls os.MkdirTemp.
+func TempDir(dir, pattern string) (name string, err error) {
+	return os.MkdirTemp(dir, pattern)
+}
diff --git a/contrib/go/_std_1.19/src/io/multi.go b/contrib/go/_std_1.19/src/io/multi.go
new file mode 100644
index 0000000000..07a9afffda
--- /dev/null
+++ b/contrib/go/_std_1.19/src/io/multi.go
@@ -0,0 +1,137 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package io
+
+type eofReader struct{}
+
+func (eofReader) Read([]byte) (int, error) {
+	return 0, EOF
+}
+
+type multiReader struct {
+	readers []Reader
+}
+
+func (mr *multiReader) Read(p []byte) (n int, err error) {
+	for len(mr.readers) > 0 {
+		// Optimization to flatten nested multiReaders (Issue 13558).
+		if len(mr.readers) == 1 {
+			if r, ok := mr.readers[0].(*multiReader); ok {
+				mr.readers = r.readers
+				continue
+			}
+		}
+		n, err = mr.readers[0].Read(p)
+		if err == EOF {
+			// Use eofReader instead of nil to avoid nil panic
+			// after performing flatten (Issue 18232).
+			mr.readers[0] = eofReader{} // permit earlier GC
+			mr.readers = mr.readers[1:]
+		}
+		if n > 0 || err != EOF {
+			if err == EOF && len(mr.readers) > 0 {
+				// Don't return EOF yet. More readers remain.
+				err = nil
+			}
+			return
+		}
+	}
+	return 0, EOF
+}
+
+func (mr *multiReader) WriteTo(w Writer) (sum int64, err error) {
+	return mr.writeToWithBuffer(w, make([]byte, 1024*32))
+}
+
+func (mr *multiReader) writeToWithBuffer(w Writer, buf []byte) (sum int64, err error) {
+	for i, r := range mr.readers {
+		var n int64
+		if subMr, ok := r.(*multiReader); ok { // reuse buffer with nested multiReaders
+			n, err = subMr.writeToWithBuffer(w, buf)
+		} else {
+			n, err = copyBuffer(w, r, buf)
+		}
+		sum += n
+		if err != nil {
+			mr.readers = mr.readers[i:] // permit resume / retry after error
+			return sum, err
+		}
+		mr.readers[i] = nil // permit early GC
+	}
+	mr.readers = nil
+	return sum, nil
+}
+
+var _ WriterTo = (*multiReader)(nil)
+
+// MultiReader returns a Reader that's the logical concatenation of
+// the provided input readers. They're read sequentially. Once all
+// inputs have returned EOF, Read will return EOF.  If any of the readers
+// return a non-nil, non-EOF error, Read will return that error.
+func MultiReader(readers ...Reader) Reader {
+	r := make([]Reader, len(readers))
+	copy(r, readers)
+	return &multiReader{r}
+}
+
+type multiWriter struct {
+	writers []Writer
+}
+
+func (t *multiWriter) Write(p []byte) (n int, err error) {
+	for _, w := range t.writers {
+		n, err = w.Write(p)
+		if err != nil {
+			return
+		}
+		if n != len(p) {
+			err = ErrShortWrite
+			return
+		}
+	}
+	return len(p), nil
+}
+
+var _ StringWriter = (*multiWriter)(nil)
+
+func (t *multiWriter) WriteString(s string) (n int, err error) {
+	var p []byte // lazily initialized if/when needed
+	for _, w := range t.writers {
+		if sw, ok := w.(StringWriter); ok {
+			n, err = sw.WriteString(s)
+		} else {
+			if p == nil {
+				p = []byte(s)
+			}
+			n, err = w.Write(p)
+		}
+		if err != nil {
+			return
+		}
+		if n != len(s) {
+			err = ErrShortWrite
+			return
+		}
+	}
+	return len(s), nil
+}
+
+// MultiWriter creates a writer that duplicates its writes to all the
+// provided writers, similar to the Unix tee(1) command.
+//
+// Each write is written to each listed writer, one at a time.
+// If a listed writer returns an error, that overall write operation
+// stops and returns the error; it does not continue down the list.
+func MultiWriter(writers ...Writer) Writer {
+	allWriters := make([]Writer, 0, len(writers))
+	for _, w := range writers {
+		if mw, ok := w.(*multiWriter); ok {
+			allWriters = append(allWriters, mw.writers...)
+		} else {
+			allWriters = append(allWriters, w)
+		}
+	}
+	return &multiWriter{allWriters}
+}
diff --git a/contrib/go/_std_1.18/src/io/pipe.go b/contrib/go/_std_1.19/src/io/pipe.go
index 2724e3f7ab..2724e3f7ab 100644
--- a/contrib/go/_std_1.18/src/io/pipe.go
+++ b/contrib/go/_std_1.19/src/io/pipe.go
diff --git a/contrib/go/_std_1.19/src/log/log.go b/contrib/go/_std_1.19/src/log/log.go
new file mode 100644
index 0000000000..f7e48d5599
--- /dev/null
+++ b/contrib/go/_std_1.19/src/log/log.go
@@ -0,0 +1,414 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package log implements a simple logging package. It defines a type, Logger,
+// with methods for formatting output. It also has a predefined 'standard'
+// Logger accessible through helper functions Print[f|ln], Fatal[f|ln], and
+// Panic[f|ln], which are easier to use than creating a Logger manually.
+// That logger writes to standard error and prints the date and time
+// of each logged message.
+// Every log message is output on a separate line: if the message being
+// printed does not end in a newline, the logger will add one.
+// The Fatal functions call os.Exit(1) after writing the log message.
+// The Panic functions call panic after writing the log message.
+package log
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"runtime"
+	"sync"
+	"sync/atomic"
+	"time"
+)
+
+// These flags define which text to prefix to each log entry generated by the Logger.
+// Bits are or'ed together to control what's printed.
+// With the exception of the Lmsgprefix flag, there is no
+// control over the order they appear (the order listed here)
+// or the format they present (as described in the comments).
+// The prefix is followed by a colon only when Llongfile or Lshortfile
+// is specified.
+// For example, flags Ldate | Ltime (or LstdFlags) produce,
+//
+//	2009/01/23 01:23:23 message
+//
+// while flags Ldate | Ltime | Lmicroseconds | Llongfile produce,
+//
+//	2009/01/23 01:23:23.123123 /a/b/c/d.go:23: message
+const (
+	Ldate         = 1 << iota     // the date in the local time zone: 2009/01/23
+	Ltime                         // the time in the local time zone: 01:23:23
+	Lmicroseconds                 // microsecond resolution: 01:23:23.123123.  assumes Ltime.
+	Llongfile                     // full file name and line number: /a/b/c/d.go:23
+	Lshortfile                    // final file name element and line number: d.go:23. overrides Llongfile
+	LUTC                          // if Ldate or Ltime is set, use UTC rather than the local time zone
+	Lmsgprefix                    // move the "prefix" from the beginning of the line to before the message
+	LstdFlags     = Ldate | Ltime // initial values for the standard logger
+)
+
+// A Logger represents an active logging object that generates lines of
+// output to an io.Writer. Each logging operation makes a single call to
+// the Writer's Write method. A Logger can be used simultaneously from
+// multiple goroutines; it guarantees to serialize access to the Writer.
+type Logger struct {
+	mu        sync.Mutex // ensures atomic writes; protects the following fields
+	prefix    string     // prefix on each line to identify the logger (but see Lmsgprefix)
+	flag      int        // properties
+	out       io.Writer  // destination for output
+	buf       []byte     // for accumulating text to write
+	isDiscard int32      // atomic boolean: whether out == io.Discard
+}
+
+// New creates a new Logger. The out variable sets the
+// destination to which log data will be written.
+// The prefix appears at the beginning of each generated log line, or
+// after the log header if the Lmsgprefix flag is provided.
+// The flag argument defines the logging properties.
+func New(out io.Writer, prefix string, flag int) *Logger {
+	l := &Logger{out: out, prefix: prefix, flag: flag}
+	if out == io.Discard {
+		l.isDiscard = 1
+	}
+	return l
+}
+
+// SetOutput sets the output destination for the logger.
+func (l *Logger) SetOutput(w io.Writer) {
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	l.out = w
+	isDiscard := int32(0)
+	if w == io.Discard {
+		isDiscard = 1
+	}
+	atomic.StoreInt32(&l.isDiscard, isDiscard)
+}
+
+var std = New(os.Stderr, "", LstdFlags)
+
+// Default returns the standard logger used by the package-level output functions.
+func Default() *Logger { return std }
+
+// Cheap integer to fixed-width decimal ASCII. Give a negative width to avoid zero-padding.
+func itoa(buf *[]byte, i int, wid int) {
+	// Assemble decimal in reverse order.
+	var b [20]byte
+	bp := len(b) - 1
+	for i >= 10 || wid > 1 {
+		wid--
+		q := i / 10
+		b[bp] = byte('0' + i - q*10)
+		bp--
+		i = q
+	}
+	// i < 10
+	b[bp] = byte('0' + i)
+	*buf = append(*buf, b[bp:]...)
+}
+
+// formatHeader writes log header to buf in following order:
+//   - l.prefix (if it's not blank and Lmsgprefix is unset),
+//   - date and/or time (if corresponding flags are provided),
+//   - file and line number (if corresponding flags are provided),
+//   - l.prefix (if it's not blank and Lmsgprefix is set).
+func (l *Logger) formatHeader(buf *[]byte, t time.Time, file string, line int) {
+	if l.flag&Lmsgprefix == 0 {
+		*buf = append(*buf, l.prefix...)
+	}
+	if l.flag&(Ldate|Ltime|Lmicroseconds) != 0 {
+		if l.flag&LUTC != 0 {
+			t = t.UTC()
+		}
+		if l.flag&Ldate != 0 {
+			year, month, day := t.Date()
+			itoa(buf, year, 4)
+			*buf = append(*buf, '/')
+			itoa(buf, int(month), 2)
+			*buf = append(*buf, '/')
+			itoa(buf, day, 2)
+			*buf = append(*buf, ' ')
+		}
+		if l.flag&(Ltime|Lmicroseconds) != 0 {
+			hour, min, sec := t.Clock()
+			itoa(buf, hour, 2)
+			*buf = append(*buf, ':')
+			itoa(buf, min, 2)
+			*buf = append(*buf, ':')
+			itoa(buf, sec, 2)
+			if l.flag&Lmicroseconds != 0 {
+				*buf = append(*buf, '.')
+				itoa(buf, t.Nanosecond()/1e3, 6)
+			}
+			*buf = append(*buf, ' ')
+		}
+	}
+	if l.flag&(Lshortfile|Llongfile) != 0 {
+		if l.flag&Lshortfile != 0 {
+			short := file
+			for i := len(file) - 1; i > 0; i-- {
+				if file[i] == '/' {
+					short = file[i+1:]
+					break
+				}
+			}
+			file = short
+		}
+		*buf = append(*buf, file...)
+		*buf = append(*buf, ':')
+		itoa(buf, line, -1)
+		*buf = append(*buf, ": "...)
+	}
+	if l.flag&Lmsgprefix != 0 {
+		*buf = append(*buf, l.prefix...)
+	}
+}
+
+// Output writes the output for a logging event. The string s contains
+// the text to print after the prefix specified by the flags of the
+// Logger. A newline is appended if the last character of s is not
+// already a newline. Calldepth is used to recover the PC and is
+// provided for generality, although at the moment on all pre-defined
+// paths it will be 2.
+func (l *Logger) Output(calldepth int, s string) error {
+	now := time.Now() // get this early.
+	var file string
+	var line int
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	if l.flag&(Lshortfile|Llongfile) != 0 {
+		// Release lock while getting caller info - it's expensive.
+		l.mu.Unlock()
+		var ok bool
+		_, file, line, ok = runtime.Caller(calldepth)
+		if !ok {
+			file = "???"
+			line = 0
+		}
+		l.mu.Lock()
+	}
+	l.buf = l.buf[:0]
+	l.formatHeader(&l.buf, now, file, line)
+	l.buf = append(l.buf, s...)
+	if len(s) == 0 || s[len(s)-1] != '\n' {
+		l.buf = append(l.buf, '\n')
+	}
+	_, err := l.out.Write(l.buf)
+	return err
+}
+
+// Printf calls l.Output to print to the logger.
+// Arguments are handled in the manner of fmt.Printf.
+func (l *Logger) Printf(format string, v ...any) {
+	if atomic.LoadInt32(&l.isDiscard) != 0 {
+		return
+	}
+	l.Output(2, fmt.Sprintf(format, v...))
+}
+
+// Print calls l.Output to print to the logger.
+// Arguments are handled in the manner of fmt.Print.
+func (l *Logger) Print(v ...any) {
+	if atomic.LoadInt32(&l.isDiscard) != 0 {
+		return
+	}
+	l.Output(2, fmt.Sprint(v...))
+}
+
+// Println calls l.Output to print to the logger.
+// Arguments are handled in the manner of fmt.Println.
+func (l *Logger) Println(v ...any) {
+	if atomic.LoadInt32(&l.isDiscard) != 0 {
+		return
+	}
+	l.Output(2, fmt.Sprintln(v...))
+}
+
+// Fatal is equivalent to l.Print() followed by a call to os.Exit(1).
+func (l *Logger) Fatal(v ...any) {
+	l.Output(2, fmt.Sprint(v...))
+	os.Exit(1)
+}
+
+// Fatalf is equivalent to l.Printf() followed by a call to os.Exit(1).
+func (l *Logger) Fatalf(format string, v ...any) {
+	l.Output(2, fmt.Sprintf(format, v...))
+	os.Exit(1)
+}
+
+// Fatalln is equivalent to l.Println() followed by a call to os.Exit(1).
+func (l *Logger) Fatalln(v ...any) {
+	l.Output(2, fmt.Sprintln(v...))
+	os.Exit(1)
+}
+
+// Panic is equivalent to l.Print() followed by a call to panic().
+func (l *Logger) Panic(v ...any) {
+	s := fmt.Sprint(v...)
+	l.Output(2, s)
+	panic(s)
+}
+
+// Panicf is equivalent to l.Printf() followed by a call to panic().
+func (l *Logger) Panicf(format string, v ...any) {
+	s := fmt.Sprintf(format, v...)
+	l.Output(2, s)
+	panic(s)
+}
+
+// Panicln is equivalent to l.Println() followed by a call to panic().
+func (l *Logger) Panicln(v ...any) {
+	s := fmt.Sprintln(v...)
+	l.Output(2, s)
+	panic(s)
+}
+
+// Flags returns the output flags for the logger.
+// The flag bits are Ldate, Ltime, and so on.
+func (l *Logger) Flags() int {
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	return l.flag
+}
+
+// SetFlags sets the output flags for the logger.
+// The flag bits are Ldate, Ltime, and so on.
+func (l *Logger) SetFlags(flag int) {
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	l.flag = flag
+}
+
+// Prefix returns the output prefix for the logger.
+func (l *Logger) Prefix() string {
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	return l.prefix
+}
+
+// SetPrefix sets the output prefix for the logger.
+func (l *Logger) SetPrefix(prefix string) {
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	l.prefix = prefix
+}
+
+// Writer returns the output destination for the logger.
+func (l *Logger) Writer() io.Writer {
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	return l.out
+}
+
+// SetOutput sets the output destination for the standard logger.
+func SetOutput(w io.Writer) {
+	std.SetOutput(w)
+}
+
+// Flags returns the output flags for the standard logger.
+// The flag bits are Ldate, Ltime, and so on.
+func Flags() int {
+	return std.Flags()
+}
+
+// SetFlags sets the output flags for the standard logger.
+// The flag bits are Ldate, Ltime, and so on.
+func SetFlags(flag int) {
+	std.SetFlags(flag)
+}
+
+// Prefix returns the output prefix for the standard logger.
+func Prefix() string {
+	return std.Prefix()
+}
+
+// SetPrefix sets the output prefix for the standard logger.
+func SetPrefix(prefix string) {
+	std.SetPrefix(prefix)
+}
+
+// Writer returns the output destination for the standard logger.
+func Writer() io.Writer {
+	return std.Writer()
+}
+
+// These functions write to the standard logger.
+
+// Print calls Output to print to the standard logger.
+// Arguments are handled in the manner of fmt.Print.
+func Print(v ...any) {
+	if atomic.LoadInt32(&std.isDiscard) != 0 {
+		return
+	}
+	std.Output(2, fmt.Sprint(v...))
+}
+
+// Printf calls Output to print to the standard logger.
+// Arguments are handled in the manner of fmt.Printf.
+func Printf(format string, v ...any) {
+	if atomic.LoadInt32(&std.isDiscard) != 0 {
+		return
+	}
+	std.Output(2, fmt.Sprintf(format, v...))
+}
+
+// Println calls Output to print to the standard logger.
+// Arguments are handled in the manner of fmt.Println.
+func Println(v ...any) {
+	if atomic.LoadInt32(&std.isDiscard) != 0 {
+		return
+	}
+	std.Output(2, fmt.Sprintln(v...))
+}
+
+// Fatal is equivalent to Print() followed by a call to os.Exit(1).
+func Fatal(v ...any) {
+	std.Output(2, fmt.Sprint(v...))
+	os.Exit(1)
+}
+
+// Fatalf is equivalent to Printf() followed by a call to os.Exit(1).
+func Fatalf(format string, v ...any) {
+	std.Output(2, fmt.Sprintf(format, v...))
+	os.Exit(1)
+}
+
+// Fatalln is equivalent to Println() followed by a call to os.Exit(1).
+func Fatalln(v ...any) {
+	std.Output(2, fmt.Sprintln(v...))
+	os.Exit(1)
+}
+
+// Panic is equivalent to Print() followed by a call to panic().
+func Panic(v ...any) {
+	s := fmt.Sprint(v...)
+	std.Output(2, s)
+	panic(s)
+}
+
+// Panicf is equivalent to Printf() followed by a call to panic().
+func Panicf(format string, v ...any) {
+	s := fmt.Sprintf(format, v...)
+	std.Output(2, s)
+	panic(s)
+}
+
+// Panicln is equivalent to Println() followed by a call to panic().
+func Panicln(v ...any) {
+	s := fmt.Sprintln(v...)
+	std.Output(2, s)
+	panic(s)
+}
+
+// Output writes the output for a logging event. The string s contains
+// the text to print after the prefix specified by the flags of the
+// Logger. A newline is appended if the last character of s is not
+// already a newline. Calldepth is the count of the number of
+// frames to skip when computing the file name and line number
+// if Llongfile or Lshortfile is set; a value of 1 will print the details
+// for the caller of Output.
+func Output(calldepth int, s string) error {
+	return std.Output(calldepth+1, s) // +1 for this frame.
+}
diff --git a/contrib/go/_std_1.19/src/math/abs.go b/contrib/go/_std_1.19/src/math/abs.go
new file mode 100644
index 0000000000..08be14548d
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/abs.go
@@ -0,0 +1,15 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Abs returns the absolute value of x.
+//
+// Special cases are:
+//
+//	Abs(±Inf) = +Inf
+//	Abs(NaN) = NaN
+func Abs(x float64) float64 {
+	return Float64frombits(Float64bits(x) &^ (1 << 63))
+}
diff --git a/contrib/go/_std_1.19/src/math/acosh.go b/contrib/go/_std_1.19/src/math/acosh.go
new file mode 100644
index 0000000000..a85d003d3e
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/acosh.go
@@ -0,0 +1,65 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// The original C code, the long comment, and the constants
+// below are from FreeBSD's /usr/src/lib/msun/src/e_acosh.c
+// and came with this notice. The go code is a simplified
+// version of the original C.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+//
+// __ieee754_acosh(x)
+// Method :
+//	Based on
+//	        acosh(x) = log [ x + sqrt(x*x-1) ]
+//	we have
+//	        acosh(x) := log(x)+ln2,	if x is large; else
+//	        acosh(x) := log(2x-1/(sqrt(x*x-1)+x)) if x>2; else
+//	        acosh(x) := log1p(t+sqrt(2.0*t+t*t)); where t=x-1.
+//
+// Special cases:
+//	acosh(x) is NaN with signal if x<1.
+//	acosh(NaN) is NaN without signal.
+//
+
+// Acosh returns the inverse hyperbolic cosine of x.
+//
+// Special cases are:
+//
+//	Acosh(+Inf) = +Inf
+//	Acosh(x) = NaN if x < 1
+//	Acosh(NaN) = NaN
+func Acosh(x float64) float64 {
+	if haveArchAcosh {
+		return archAcosh(x)
+	}
+	return acosh(x)
+}
+
+func acosh(x float64) float64 {
+	const Large = 1 << 28 // 2**28
+	// first case is special case
+	switch {
+	case x < 1 || IsNaN(x):
+		return NaN()
+	case x == 1:
+		return 0
+	case x >= Large:
+		return Log(x) + Ln2 // x > 2**28
+	case x > 2:
+		return Log(2*x - 1/(x+Sqrt(x*x-1))) // 2**28 > x > 2
+	}
+	t := x - 1
+	return Log1p(t + Sqrt(2*t+t*t)) // 2 >= x > 1
+}
diff --git a/contrib/go/_std_1.19/src/math/asin.go b/contrib/go/_std_1.19/src/math/asin.go
new file mode 100644
index 0000000000..8e1b2ab491
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/asin.go
@@ -0,0 +1,67 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+	Floating-point arcsine and arccosine.
+
+	They are implemented by computing the arctangent
+	after appropriate range reduction.
+*/
+
+// Asin returns the arcsine, in radians, of x.
+//
+// Special cases are:
+//
+//	Asin(±0) = ±0
+//	Asin(x) = NaN if x < -1 or x > 1
+func Asin(x float64) float64 {
+	if haveArchAsin {
+		return archAsin(x)
+	}
+	return asin(x)
+}
+
+func asin(x float64) float64 {
+	if x == 0 {
+		return x // special case
+	}
+	sign := false
+	if x < 0 {
+		x = -x
+		sign = true
+	}
+	if x > 1 {
+		return NaN() // special case
+	}
+
+	temp := Sqrt(1 - x*x)
+	if x > 0.7 {
+		temp = Pi/2 - satan(temp/x)
+	} else {
+		temp = satan(x / temp)
+	}
+
+	if sign {
+		temp = -temp
+	}
+	return temp
+}
+
+// Acos returns the arccosine, in radians, of x.
+//
+// Special case is:
+//
+//	Acos(x) = NaN if x < -1 or x > 1
+func Acos(x float64) float64 {
+	if haveArchAcos {
+		return archAcos(x)
+	}
+	return acos(x)
+}
+
+func acos(x float64) float64 {
+	return Pi/2 - Asin(x)
+}
diff --git a/contrib/go/_std_1.19/src/math/asinh.go b/contrib/go/_std_1.19/src/math/asinh.go
new file mode 100644
index 0000000000..6f6e9e4608
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/asinh.go
@@ -0,0 +1,77 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// The original C code, the long comment, and the constants
+// below are from FreeBSD's /usr/src/lib/msun/src/s_asinh.c
+// and came with this notice. The go code is a simplified
+// version of the original C.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+//
+// asinh(x)
+// Method :
+//	Based on
+//	        asinh(x) = sign(x) * log [ |x| + sqrt(x*x+1) ]
+//	we have
+//	asinh(x) := x  if  1+x*x=1,
+//	         := sign(x)*(log(x)+ln2)) for large |x|, else
+//	         := sign(x)*log(2|x|+1/(|x|+sqrt(x*x+1))) if|x|>2, else
+//	         := sign(x)*log1p(|x| + x**2/(1 + sqrt(1+x**2)))
+//
+
+// Asinh returns the inverse hyperbolic sine of x.
+//
+// Special cases are:
+//
+//	Asinh(±0) = ±0
+//	Asinh(±Inf) = ±Inf
+//	Asinh(NaN) = NaN
+func Asinh(x float64) float64 {
+	if haveArchAsinh {
+		return archAsinh(x)
+	}
+	return asinh(x)
+}
+
+func asinh(x float64) float64 {
+	const (
+		Ln2      = 6.93147180559945286227e-01 // 0x3FE62E42FEFA39EF
+		NearZero = 1.0 / (1 << 28)            // 2**-28
+		Large    = 1 << 28                    // 2**28
+	)
+	// special cases
+	if IsNaN(x) || IsInf(x, 0) {
+		return x
+	}
+	sign := false
+	if x < 0 {
+		x = -x
+		sign = true
+	}
+	var temp float64
+	switch {
+	case x > Large:
+		temp = Log(x) + Ln2 // |x| > 2**28
+	case x > 2:
+		temp = Log(2*x + 1/(Sqrt(x*x+1)+x)) // 2**28 > |x| > 2.0
+	case x < NearZero:
+		temp = x // |x| < 2**-28
+	default:
+		temp = Log1p(x + x*x/(1+Sqrt(1+x*x))) // 2.0 > |x| > 2**-28
+	}
+	if sign {
+		temp = -temp
+	}
+	return temp
+}
diff --git a/contrib/go/_std_1.19/src/math/atan.go b/contrib/go/_std_1.19/src/math/atan.go
new file mode 100644
index 0000000000..e722e99757
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/atan.go
@@ -0,0 +1,111 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+	Floating-point arctangent.
+*/
+
+// The original C code, the long comment, and the constants below were
+// from http://netlib.sandia.gov/cephes/cmath/atan.c, available from
+// http://www.netlib.org/cephes/cmath.tgz.
+// The go code is a version of the original C.
+//
+// atan.c
+// Inverse circular tangent (arctangent)
+//
+// SYNOPSIS:
+// double x, y, atan();
+// y = atan( x );
+//
+// DESCRIPTION:
+// Returns radian angle between -pi/2 and +pi/2 whose tangent is x.
+//
+// Range reduction is from three intervals into the interval from zero to 0.66.
+// The approximant uses a rational function of degree 4/5 of the form
+// x + x**3 P(x)/Q(x).
+//
+// ACCURACY:
+//                      Relative error:
+// arithmetic   domain    # trials  peak     rms
+//    DEC       -10, 10   50000     2.4e-17  8.3e-18
+//    IEEE      -10, 10   10^6      1.8e-16  5.0e-17
+//
+// Cephes Math Library Release 2.8:  June, 2000
+// Copyright 1984, 1987, 1989, 1992, 2000 by Stephen L. Moshier
+//
+// The readme file at http://netlib.sandia.gov/cephes/ says:
+//    Some software in this archive may be from the book _Methods and
+// Programs for Mathematical Functions_ (Prentice-Hall or Simon & Schuster
+// International, 1989) or from the Cephes Mathematical Library, a
+// commercial product. In either event, it is copyrighted by the author.
+// What you see here may be used freely but it comes with no support or
+// guarantee.
+//
+//   The two known misprints in the book are repaired here in the
+// source listings for the gamma function and the incomplete beta
+// integral.
+//
+//   Stephen L. Moshier
+//   moshier@na-net.ornl.gov
+
+// xatan evaluates a series valid in the range [0, 0.66].
+func xatan(x float64) float64 {
+	const (
+		P0 = -8.750608600031904122785e-01
+		P1 = -1.615753718733365076637e+01
+		P2 = -7.500855792314704667340e+01
+		P3 = -1.228866684490136173410e+02
+		P4 = -6.485021904942025371773e+01
+		Q0 = +2.485846490142306297962e+01
+		Q1 = +1.650270098316988542046e+02
+		Q2 = +4.328810604912902668951e+02
+		Q3 = +4.853903996359136964868e+02
+		Q4 = +1.945506571482613964425e+02
+	)
+	z := x * x
+	z = z * ((((P0*z+P1)*z+P2)*z+P3)*z + P4) / (((((z+Q0)*z+Q1)*z+Q2)*z+Q3)*z + Q4)
+	z = x*z + x
+	return z
+}
+
+// satan reduces its argument (known to be positive)
+// to the range [0, 0.66] and calls xatan.
+func satan(x float64) float64 {
+	const (
+		Morebits = 6.123233995736765886130e-17 // pi/2 = PIO2 + Morebits
+		Tan3pio8 = 2.41421356237309504880      // tan(3*pi/8)
+	)
+	if x <= 0.66 {
+		return xatan(x)
+	}
+	if x > Tan3pio8 {
+		return Pi/2 - xatan(1/x) + Morebits
+	}
+	return Pi/4 + xatan((x-1)/(x+1)) + 0.5*Morebits
+}
+
+// Atan returns the arctangent, in radians, of x.
+//
+// Special cases are:
+//
+//	Atan(±0) = ±0
+//	Atan(±Inf) = ±Pi/2
+func Atan(x float64) float64 {
+	if haveArchAtan {
+		return archAtan(x)
+	}
+	return atan(x)
+}
+
+func atan(x float64) float64 {
+	if x == 0 {
+		return x
+	}
+	if x > 0 {
+		return satan(x)
+	}
+	return -satan(-x)
+}
diff --git a/contrib/go/_std_1.19/src/math/atan2.go b/contrib/go/_std_1.19/src/math/atan2.go
new file mode 100644
index 0000000000..c324ed0a15
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/atan2.go
@@ -0,0 +1,77 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Atan2 returns the arc tangent of y/x, using
+// the signs of the two to determine the quadrant
+// of the return value.
+//
+// Special cases are (in order):
+//
+//	Atan2(y, NaN) = NaN
+//	Atan2(NaN, x) = NaN
+//	Atan2(+0, x>=0) = +0
+//	Atan2(-0, x>=0) = -0
+//	Atan2(+0, x<=-0) = +Pi
+//	Atan2(-0, x<=-0) = -Pi
+//	Atan2(y>0, 0) = +Pi/2
+//	Atan2(y<0, 0) = -Pi/2
+//	Atan2(+Inf, +Inf) = +Pi/4
+//	Atan2(-Inf, +Inf) = -Pi/4
+//	Atan2(+Inf, -Inf) = 3Pi/4
+//	Atan2(-Inf, -Inf) = -3Pi/4
+//	Atan2(y, +Inf) = 0
+//	Atan2(y>0, -Inf) = +Pi
+//	Atan2(y<0, -Inf) = -Pi
+//	Atan2(+Inf, x) = +Pi/2
+//	Atan2(-Inf, x) = -Pi/2
+func Atan2(y, x float64) float64 {
+	if haveArchAtan2 {
+		return archAtan2(y, x)
+	}
+	return atan2(y, x)
+}
+
+func atan2(y, x float64) float64 {
+	// special cases
+	switch {
+	case IsNaN(y) || IsNaN(x):
+		return NaN()
+	case y == 0:
+		if x >= 0 && !Signbit(x) {
+			return Copysign(0, y)
+		}
+		return Copysign(Pi, y)
+	case x == 0:
+		return Copysign(Pi/2, y)
+	case IsInf(x, 0):
+		if IsInf(x, 1) {
+			switch {
+			case IsInf(y, 0):
+				return Copysign(Pi/4, y)
+			default:
+				return Copysign(0, y)
+			}
+		}
+		switch {
+		case IsInf(y, 0):
+			return Copysign(3*Pi/4, y)
+		default:
+			return Copysign(Pi, y)
+		}
+	case IsInf(y, 0):
+		return Copysign(Pi/2, y)
+	}
+
+	// Call atan and determine the quadrant.
+	q := Atan(y / x)
+	if x < 0 {
+		if q <= 0 {
+			return q + Pi
+		}
+		return q - Pi
+	}
+	return q
+}
diff --git a/contrib/go/_std_1.19/src/math/atanh.go b/contrib/go/_std_1.19/src/math/atanh.go
new file mode 100644
index 0000000000..9d594625a5
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/atanh.go
@@ -0,0 +1,85 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// The original C code, the long comment, and the constants
+// below are from FreeBSD's /usr/src/lib/msun/src/e_atanh.c
+// and came with this notice. The go code is a simplified
+// version of the original C.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+//
+// __ieee754_atanh(x)
+// Method :
+//	1. Reduce x to positive by atanh(-x) = -atanh(x)
+//	2. For x>=0.5
+//	            1              2x                          x
+//	atanh(x) = --- * log(1 + -------) = 0.5 * log1p(2 * --------)
+//	            2             1 - x                      1 - x
+//
+//	For x<0.5
+//	atanh(x) = 0.5*log1p(2x+2x*x/(1-x))
+//
+// Special cases:
+//	atanh(x) is NaN if |x| > 1 with signal;
+//	atanh(NaN) is that NaN with no signal;
+//	atanh(+-1) is +-INF with signal.
+//
+
+// Atanh returns the inverse hyperbolic tangent of x.
+//
+// Special cases are:
+//
+//	Atanh(1) = +Inf
+//	Atanh(±0) = ±0
+//	Atanh(-1) = -Inf
+//	Atanh(x) = NaN if x < -1 or x > 1
+//	Atanh(NaN) = NaN
+func Atanh(x float64) float64 {
+	if haveArchAtanh {
+		return archAtanh(x)
+	}
+	return atanh(x)
+}
+
+func atanh(x float64) float64 {
+	const NearZero = 1.0 / (1 << 28) // 2**-28
+	// special cases
+	switch {
+	case x < -1 || x > 1 || IsNaN(x):
+		return NaN()
+	case x == 1:
+		return Inf(1)
+	case x == -1:
+		return Inf(-1)
+	}
+	sign := false
+	if x < 0 {
+		x = -x
+		sign = true
+	}
+	var temp float64
+	switch {
+	case x < NearZero:
+		temp = x
+	case x < 0.5:
+		temp = x + x
+		temp = 0.5 * Log1p(temp+temp*x/(1-x))
+	default:
+		temp = 0.5 * Log1p((x+x)/(1-x))
+	}
+	if sign {
+		temp = -temp
+	}
+	return temp
+}
diff --git a/contrib/go/_std_1.18/src/math/big/accuracy_string.go b/contrib/go/_std_1.19/src/math/big/accuracy_string.go
index 1501ace00d..1501ace00d 100644
--- a/contrib/go/_std_1.18/src/math/big/accuracy_string.go
+++ b/contrib/go/_std_1.19/src/math/big/accuracy_string.go
diff --git a/contrib/go/_std_1.19/src/math/big/arith.go b/contrib/go/_std_1.19/src/math/big/arith.go
new file mode 100644
index 0000000000..06e63e2574
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/big/arith.go
@@ -0,0 +1,277 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file provides Go implementations of elementary multi-precision
+// arithmetic operations on word vectors. These have the suffix _g.
+// These are needed for platforms without assembly implementations of these routines.
+// This file also contains elementary operations that can be implemented
+// sufficiently efficiently in Go.
+
+package big
+
+import "math/bits"
+
+// A Word represents a single digit of a multi-precision unsigned integer.
+type Word uint
+
+const (
+	_S = _W / 8 // word size in bytes
+
+	_W = bits.UintSize // word size in bits
+	_B = 1 << _W       // digit base
+	_M = _B - 1        // digit mask
+)
+
+// Many of the loops in this file are of the form
+//   for i := 0; i < len(z) && i < len(x) && i < len(y); i++
+// i < len(z) is the real condition.
+// However, checking i < len(x) && i < len(y) as well is faster than
+// having the compiler do a bounds check in the body of the loop;
+// remarkably it is even faster than hoisting the bounds check
+// out of the loop, by doing something like
+//   _, _ = x[len(z)-1], y[len(z)-1]
+// There are other ways to hoist the bounds check out of the loop,
+// but the compiler's BCE isn't powerful enough for them (yet?).
+// See the discussion in CL 164966.
+
+// ----------------------------------------------------------------------------
+// Elementary operations on words
+//
+// These operations are used by the vector operations below.
+
+// z1<<_W + z0 = x*y
+func mulWW(x, y Word) (z1, z0 Word) {
+	hi, lo := bits.Mul(uint(x), uint(y))
+	return Word(hi), Word(lo)
+}
+
+// z1<<_W + z0 = x*y + c
+func mulAddWWW_g(x, y, c Word) (z1, z0 Word) {
+	hi, lo := bits.Mul(uint(x), uint(y))
+	var cc uint
+	lo, cc = bits.Add(lo, uint(c), 0)
+	return Word(hi + cc), Word(lo)
+}
+
+// nlz returns the number of leading zeros in x.
+// Wraps bits.LeadingZeros call for convenience.
+func nlz(x Word) uint {
+	return uint(bits.LeadingZeros(uint(x)))
+}
+
+// The resulting carry c is either 0 or 1.
+func addVV_g(z, x, y []Word) (c Word) {
+	// The comment near the top of this file discusses this for loop condition.
+	for i := 0; i < len(z) && i < len(x) && i < len(y); i++ {
+		zi, cc := bits.Add(uint(x[i]), uint(y[i]), uint(c))
+		z[i] = Word(zi)
+		c = Word(cc)
+	}
+	return
+}
+
+// The resulting carry c is either 0 or 1.
+func subVV_g(z, x, y []Word) (c Word) {
+	// The comment near the top of this file discusses this for loop condition.
+	for i := 0; i < len(z) && i < len(x) && i < len(y); i++ {
+		zi, cc := bits.Sub(uint(x[i]), uint(y[i]), uint(c))
+		z[i] = Word(zi)
+		c = Word(cc)
+	}
+	return
+}
+
+// The resulting carry c is either 0 or 1.
+func addVW_g(z, x []Word, y Word) (c Word) {
+	c = y
+	// The comment near the top of this file discusses this for loop condition.
+	for i := 0; i < len(z) && i < len(x); i++ {
+		zi, cc := bits.Add(uint(x[i]), uint(c), 0)
+		z[i] = Word(zi)
+		c = Word(cc)
+	}
+	return
+}
+
+// addVWlarge is addVW, but intended for large z.
+// The only difference is that we check on every iteration
+// whether we are done with carries,
+// and if so, switch to a much faster copy instead.
+// This is only a good idea for large z,
+// because the overhead of the check and the function call
+// outweigh the benefits when z is small.
+func addVWlarge(z, x []Word, y Word) (c Word) {
+	c = y
+	// The comment near the top of this file discusses this for loop condition.
+	for i := 0; i < len(z) && i < len(x); i++ {
+		if c == 0 {
+			copy(z[i:], x[i:])
+			return
+		}
+		zi, cc := bits.Add(uint(x[i]), uint(c), 0)
+		z[i] = Word(zi)
+		c = Word(cc)
+	}
+	return
+}
+
+func subVW_g(z, x []Word, y Word) (c Word) {
+	c = y
+	// The comment near the top of this file discusses this for loop condition.
+	for i := 0; i < len(z) && i < len(x); i++ {
+		zi, cc := bits.Sub(uint(x[i]), uint(c), 0)
+		z[i] = Word(zi)
+		c = Word(cc)
+	}
+	return
+}
+
+// subVWlarge is to subVW as addVWlarge is to addVW.
+func subVWlarge(z, x []Word, y Word) (c Word) {
+	c = y
+	// The comment near the top of this file discusses this for loop condition.
+	for i := 0; i < len(z) && i < len(x); i++ {
+		if c == 0 {
+			copy(z[i:], x[i:])
+			return
+		}
+		zi, cc := bits.Sub(uint(x[i]), uint(c), 0)
+		z[i] = Word(zi)
+		c = Word(cc)
+	}
+	return
+}
+
+func shlVU_g(z, x []Word, s uint) (c Word) {
+	if s == 0 {
+		copy(z, x)
+		return
+	}
+	if len(z) == 0 {
+		return
+	}
+	s &= _W - 1 // hint to the compiler that shifts by s don't need guard code
+	ŝ := _W - s
+	ŝ &= _W - 1 // ditto
+	c = x[len(z)-1] >> ŝ
+	for i := len(z) - 1; i > 0; i-- {
+		z[i] = x[i]<<s | x[i-1]>>ŝ
+	}
+	z[0] = x[0] << s
+	return
+}
+
+func shrVU_g(z, x []Word, s uint) (c Word) {
+	if s == 0 {
+		copy(z, x)
+		return
+	}
+	if len(z) == 0 {
+		return
+	}
+	if len(x) != len(z) {
+		// This is an invariant guaranteed by the caller.
+		panic("len(x) != len(z)")
+	}
+	s &= _W - 1 // hint to the compiler that shifts by s don't need guard code
+	ŝ := _W - s
+	ŝ &= _W - 1 // ditto
+	c = x[0] << ŝ
+	for i := 1; i < len(z); i++ {
+		z[i-1] = x[i-1]>>s | x[i]<<ŝ
+	}
+	z[len(z)-1] = x[len(z)-1] >> s
+	return
+}
+
+func mulAddVWW_g(z, x []Word, y, r Word) (c Word) {
+	c = r
+	// The comment near the top of this file discusses this for loop condition.
+	for i := 0; i < len(z) && i < len(x); i++ {
+		c, z[i] = mulAddWWW_g(x[i], y, c)
+	}
+	return
+}
+
+func addMulVVW_g(z, x []Word, y Word) (c Word) {
+	// The comment near the top of this file discusses this for loop condition.
+	for i := 0; i < len(z) && i < len(x); i++ {
+		z1, z0 := mulAddWWW_g(x[i], y, z[i])
+		lo, cc := bits.Add(uint(z0), uint(c), 0)
+		c, z[i] = Word(cc), Word(lo)
+		c += z1
+	}
+	return
+}
+
+// q = ( x1 << _W + x0 - r)/y. m = floor(( _B^2 - 1 ) / d - _B). Requiring x1<y.
+// An approximate reciprocal with a reference to "Improved Division by Invariant Integers
+// (IEEE Transactions on Computers, 11 Jun. 2010)"
+func divWW(x1, x0, y, m Word) (q, r Word) {
+	s := nlz(y)
+	if s != 0 {
+		x1 = x1<<s | x0>>(_W-s)
+		x0 <<= s
+		y <<= s
+	}
+	d := uint(y)
+	// We know that
+	//   m = ⎣(B^2-1)/d⎦-B
+	//   ⎣(B^2-1)/d⎦ = m+B
+	//   (B^2-1)/d = m+B+delta1    0 <= delta1 <= (d-1)/d
+	//   B^2/d = m+B+delta2        0 <= delta2 <= 1
+	// The quotient we're trying to compute is
+	//   quotient = ⎣(x1*B+x0)/d⎦
+	//            = ⎣(x1*B*(B^2/d)+x0*(B^2/d))/B^2⎦
+	//            = ⎣(x1*B*(m+B+delta2)+x0*(m+B+delta2))/B^2⎦
+	//            = ⎣(x1*m+x1*B+x0)/B + x0*m/B^2 + delta2*(x1*B+x0)/B^2⎦
+	// The latter two terms of this three-term sum are between 0 and 1.
+	// So we can compute just the first term, and we will be low by at most 2.
+	t1, t0 := bits.Mul(uint(m), uint(x1))
+	_, c := bits.Add(t0, uint(x0), 0)
+	t1, _ = bits.Add(t1, uint(x1), c)
+	// The quotient is either t1, t1+1, or t1+2.
+	// We'll try t1 and adjust if needed.
+	qq := t1
+	// compute remainder r=x-d*q.
+	dq1, dq0 := bits.Mul(d, qq)
+	r0, b := bits.Sub(uint(x0), dq0, 0)
+	r1, _ := bits.Sub(uint(x1), dq1, b)
+	// The remainder we just computed is bounded above by B+d:
+	// r = x1*B + x0 - d*q.
+	//   = x1*B + x0 - d*⎣(x1*m+x1*B+x0)/B⎦
+	//   = x1*B + x0 - d*((x1*m+x1*B+x0)/B-alpha)                                   0 <= alpha < 1
+	//   = x1*B + x0 - x1*d/B*m                         - x1*d - x0*d/B + d*alpha
+	//   = x1*B + x0 - x1*d/B*⎣(B^2-1)/d-B⎦             - x1*d - x0*d/B + d*alpha
+	//   = x1*B + x0 - x1*d/B*⎣(B^2-1)/d-B⎦             - x1*d - x0*d/B + d*alpha
+	//   = x1*B + x0 - x1*d/B*((B^2-1)/d-B-beta)        - x1*d - x0*d/B + d*alpha   0 <= beta < 1
+	//   = x1*B + x0 - x1*B + x1/B + x1*d + x1*d/B*beta - x1*d - x0*d/B + d*alpha
+	//   =        x0        + x1/B        + x1*d/B*beta        - x0*d/B + d*alpha
+	//   = x0*(1-d/B) + x1*(1+d*beta)/B + d*alpha
+	//   <  B*(1-d/B) +  d*B/B          + d          because x0<B (and 1-d/B>0), x1<d, 1+d*beta<=B, alpha<1
+	//   =  B - d     +  d              + d
+	//   = B+d
+	// So r1 can only be 0 or 1. If r1 is 1, then we know q was too small.
+	// Add 1 to q and subtract d from r. That guarantees that r is <B, so
+	// we no longer need to keep track of r1.
+	if r1 != 0 {
+		qq++
+		r0 -= d
+	}
+	// If the remainder is still too large, increment q one more time.
+	if r0 >= d {
+		qq++
+		r0 -= d
+	}
+	return Word(qq), Word(r0 >> s)
+}
+
+// reciprocalWord return the reciprocal of the divisor. rec = floor(( _B^2 - 1 ) / u - _B). u = d1 << nlz(d1).
+func reciprocalWord(d1 Word) Word {
+	u := uint(d1 << nlz(d1))
+	x1 := ^u
+	x0 := uint(_M)
+	rec, _ := bits.Div(x1, x0, u) // (_B^2-1)/U-_B = (_B*(_M-C)+_M)/U
+	return Word(rec)
+}
diff --git a/contrib/go/_std_1.18/src/math/big/arith_amd64.go b/contrib/go/_std_1.19/src/math/big/arith_amd64.go
index 89108fe149..89108fe149 100644
--- a/contrib/go/_std_1.18/src/math/big/arith_amd64.go
+++ b/contrib/go/_std_1.19/src/math/big/arith_amd64.go
diff --git a/contrib/go/_std_1.19/src/math/big/arith_amd64.s b/contrib/go/_std_1.19/src/math/big/arith_amd64.s
new file mode 100644
index 0000000000..b1e914c2bd
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/big/arith_amd64.s
@@ -0,0 +1,516 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !math_big_pure_go
+// +build !math_big_pure_go
+
+#include "textflag.h"
+
+// This file provides fast assembly versions for the elementary
+// arithmetic operations on vectors implemented in arith.go.
+
+// The carry bit is saved with SBBQ Rx, Rx: if the carry was set, Rx is -1, otherwise it is 0.
+// It is restored with ADDQ Rx, Rx: if Rx was -1 the carry is set, otherwise it is cleared.
+// This is faster than using rotate instructions.
+
+// func addVV(z, x, y []Word) (c Word)
+TEXT ·addVV(SB),NOSPLIT,$0
+	MOVQ z_len+8(FP), DI
+	MOVQ x+24(FP), R8
+	MOVQ y+48(FP), R9
+	MOVQ z+0(FP), R10
+
+	MOVQ $0, CX		// c = 0
+	MOVQ $0, SI		// i = 0
+
+	// s/JL/JMP/ below to disable the unrolled loop
+	SUBQ $4, DI		// n -= 4
+	JL V1			// if n < 0 goto V1
+
+U1:	// n >= 0
+	// regular loop body unrolled 4x
+	ADDQ CX, CX		// restore CF
+	MOVQ 0(R8)(SI*8), R11
+	MOVQ 8(R8)(SI*8), R12
+	MOVQ 16(R8)(SI*8), R13
+	MOVQ 24(R8)(SI*8), R14
+	ADCQ 0(R9)(SI*8), R11
+	ADCQ 8(R9)(SI*8), R12
+	ADCQ 16(R9)(SI*8), R13
+	ADCQ 24(R9)(SI*8), R14
+	MOVQ R11, 0(R10)(SI*8)
+	MOVQ R12, 8(R10)(SI*8)
+	MOVQ R13, 16(R10)(SI*8)
+	MOVQ R14, 24(R10)(SI*8)
+	SBBQ CX, CX		// save CF
+
+	ADDQ $4, SI		// i += 4
+	SUBQ $4, DI		// n -= 4
+	JGE U1			// if n >= 0 goto U1
+
+V1:	ADDQ $4, DI		// n += 4
+	JLE E1			// if n <= 0 goto E1
+
+L1:	// n > 0
+	ADDQ CX, CX		// restore CF
+	MOVQ 0(R8)(SI*8), R11
+	ADCQ 0(R9)(SI*8), R11
+	MOVQ R11, 0(R10)(SI*8)
+	SBBQ CX, CX		// save CF
+
+	ADDQ $1, SI		// i++
+	SUBQ $1, DI		// n--
+	JG L1			// if n > 0 goto L1
+
+E1:	NEGQ CX
+	MOVQ CX, c+72(FP)	// return c
+	RET
+
+
+// func subVV(z, x, y []Word) (c Word)
+// (same as addVV except for SBBQ instead of ADCQ and label names)
+TEXT ·subVV(SB),NOSPLIT,$0
+	MOVQ z_len+8(FP), DI
+	MOVQ x+24(FP), R8
+	MOVQ y+48(FP), R9
+	MOVQ z+0(FP), R10
+
+	MOVQ $0, CX		// c = 0
+	MOVQ $0, SI		// i = 0
+
+	// s/JL/JMP/ below to disable the unrolled loop
+	SUBQ $4, DI		// n -= 4
+	JL V2			// if n < 0 goto V2
+
+U2:	// n >= 0
+	// regular loop body unrolled 4x
+	ADDQ CX, CX		// restore CF
+	MOVQ 0(R8)(SI*8), R11
+	MOVQ 8(R8)(SI*8), R12
+	MOVQ 16(R8)(SI*8), R13
+	MOVQ 24(R8)(SI*8), R14
+	SBBQ 0(R9)(SI*8), R11
+	SBBQ 8(R9)(SI*8), R12
+	SBBQ 16(R9)(SI*8), R13
+	SBBQ 24(R9)(SI*8), R14
+	MOVQ R11, 0(R10)(SI*8)
+	MOVQ R12, 8(R10)(SI*8)
+	MOVQ R13, 16(R10)(SI*8)
+	MOVQ R14, 24(R10)(SI*8)
+	SBBQ CX, CX		// save CF
+
+	ADDQ $4, SI		// i += 4
+	SUBQ $4, DI		// n -= 4
+	JGE U2			// if n >= 0 goto U2
+
+V2:	ADDQ $4, DI		// n += 4
+	JLE E2			// if n <= 0 goto E2
+
+L2:	// n > 0
+	ADDQ CX, CX		// restore CF
+	MOVQ 0(R8)(SI*8), R11
+	SBBQ 0(R9)(SI*8), R11
+	MOVQ R11, 0(R10)(SI*8)
+	SBBQ CX, CX		// save CF
+
+	ADDQ $1, SI		// i++
+	SUBQ $1, DI		// n--
+	JG L2			// if n > 0 goto L2
+
+E2:	NEGQ CX
+	MOVQ CX, c+72(FP)	// return c
+	RET
+
+
+// func addVW(z, x []Word, y Word) (c Word)
+TEXT ·addVW(SB),NOSPLIT,$0
+	MOVQ z_len+8(FP), DI
+	CMPQ DI, $32
+	JG large
+	MOVQ x+24(FP), R8
+	MOVQ y+48(FP), CX	// c = y
+	MOVQ z+0(FP), R10
+
+	MOVQ $0, SI		// i = 0
+
+	// s/JL/JMP/ below to disable the unrolled loop
+	SUBQ $4, DI		// n -= 4
+	JL V3			// if n < 4 goto V3
+
+U3:	// n >= 0
+	// regular loop body unrolled 4x
+	MOVQ 0(R8)(SI*8), R11
+	MOVQ 8(R8)(SI*8), R12
+	MOVQ 16(R8)(SI*8), R13
+	MOVQ 24(R8)(SI*8), R14
+	ADDQ CX, R11
+	ADCQ $0, R12
+	ADCQ $0, R13
+	ADCQ $0, R14
+	SBBQ CX, CX		// save CF
+	NEGQ CX
+	MOVQ R11, 0(R10)(SI*8)
+	MOVQ R12, 8(R10)(SI*8)
+	MOVQ R13, 16(R10)(SI*8)
+	MOVQ R14, 24(R10)(SI*8)
+
+	ADDQ $4, SI		// i += 4
+	SUBQ $4, DI		// n -= 4
+	JGE U3			// if n >= 0 goto U3
+
+V3:	ADDQ $4, DI		// n += 4
+	JLE E3			// if n <= 0 goto E3
+
+L3:	// n > 0
+	ADDQ 0(R8)(SI*8), CX
+	MOVQ CX, 0(R10)(SI*8)
+	SBBQ CX, CX		// save CF
+	NEGQ CX
+
+	ADDQ $1, SI		// i++
+	SUBQ $1, DI		// n--
+	JG L3			// if n > 0 goto L3
+
+E3:	MOVQ CX, c+56(FP)	// return c
+	RET
+large:
+	JMP ·addVWlarge(SB)
+
+
+// func subVW(z, x []Word, y Word) (c Word)
+// (same as addVW except for SUBQ/SBBQ instead of ADDQ/ADCQ and label names)
+TEXT ·subVW(SB),NOSPLIT,$0
+	MOVQ z_len+8(FP), DI
+	CMPQ DI, $32
+	JG large
+	MOVQ x+24(FP), R8
+	MOVQ y+48(FP), CX	// c = y
+	MOVQ z+0(FP), R10
+
+	MOVQ $0, SI		// i = 0
+
+	// s/JL/JMP/ below to disable the unrolled loop
+	SUBQ $4, DI		// n -= 4
+	JL V4			// if n < 4 goto V4
+
+U4:	// n >= 0
+	// regular loop body unrolled 4x
+	MOVQ 0(R8)(SI*8), R11
+	MOVQ 8(R8)(SI*8), R12
+	MOVQ 16(R8)(SI*8), R13
+	MOVQ 24(R8)(SI*8), R14
+	SUBQ CX, R11
+	SBBQ $0, R12
+	SBBQ $0, R13
+	SBBQ $0, R14
+	SBBQ CX, CX		// save CF
+	NEGQ CX
+	MOVQ R11, 0(R10)(SI*8)
+	MOVQ R12, 8(R10)(SI*8)
+	MOVQ R13, 16(R10)(SI*8)
+	MOVQ R14, 24(R10)(SI*8)
+
+	ADDQ $4, SI		// i += 4
+	SUBQ $4, DI		// n -= 4
+	JGE U4			// if n >= 0 goto U4
+
+V4:	ADDQ $4, DI		// n += 4
+	JLE E4			// if n <= 0 goto E4
+
+L4:	// n > 0
+	MOVQ 0(R8)(SI*8), R11
+	SUBQ CX, R11
+	MOVQ R11, 0(R10)(SI*8)
+	SBBQ CX, CX		// save CF
+	NEGQ CX
+
+	ADDQ $1, SI		// i++
+	SUBQ $1, DI		// n--
+	JG L4			// if n > 0 goto L4
+
+E4:	MOVQ CX, c+56(FP)	// return c
+	RET
+large:
+	JMP ·subVWlarge(SB)
+
+
+// func shlVU(z, x []Word, s uint) (c Word)
+TEXT ·shlVU(SB),NOSPLIT,$0
+	MOVQ z_len+8(FP), BX	// i = z
+	SUBQ $1, BX		// i--
+	JL X8b			// i < 0	(n <= 0)
+
+	// n > 0
+	MOVQ z+0(FP), R10
+	MOVQ x+24(FP), R8
+	MOVQ s+48(FP), CX
+	MOVQ (R8)(BX*8), AX	// w1 = x[n-1]
+	MOVQ $0, DX
+	SHLQ CX, AX, DX		// w1>>ŝ
+	MOVQ DX, c+56(FP)
+
+	CMPQ BX, $0
+	JLE X8a			// i <= 0
+
+	// i > 0
+L8:	MOVQ AX, DX		// w = w1
+	MOVQ -8(R8)(BX*8), AX	// w1 = x[i-1]
+	SHLQ CX, AX, DX		// w<<s | w1>>ŝ
+	MOVQ DX, (R10)(BX*8)	// z[i] = w<<s | w1>>ŝ
+	SUBQ $1, BX		// i--
+	JG L8			// i > 0
+
+	// i <= 0
+X8a:	SHLQ CX, AX		// w1<<s
+	MOVQ AX, (R10)		// z[0] = w1<<s
+	RET
+
+X8b:	MOVQ $0, c+56(FP)
+	RET
+
+
+// func shrVU(z, x []Word, s uint) (c Word)
+TEXT ·shrVU(SB),NOSPLIT,$0
+	MOVQ z_len+8(FP), R11
+	SUBQ $1, R11		// n--
+	JL X9b			// n < 0	(n <= 0)
+
+	// n > 0
+	MOVQ z+0(FP), R10
+	MOVQ x+24(FP), R8
+	MOVQ s+48(FP), CX
+	MOVQ (R8), AX		// w1 = x[0]
+	MOVQ $0, DX
+	SHRQ CX, AX, DX		// w1<<ŝ
+	MOVQ DX, c+56(FP)
+
+	MOVQ $0, BX		// i = 0
+	JMP E9
+
+	// i < n-1
+L9:	MOVQ AX, DX		// w = w1
+	MOVQ 8(R8)(BX*8), AX	// w1 = x[i+1]
+	SHRQ CX, AX, DX		// w>>s | w1<<ŝ
+	MOVQ DX, (R10)(BX*8)	// z[i] = w>>s | w1<<ŝ
+	ADDQ $1, BX		// i++
+
+E9:	CMPQ BX, R11
+	JL L9			// i < n-1
+
+	// i >= n-1
+X9a:	SHRQ CX, AX		// w1>>s
+	MOVQ AX, (R10)(R11*8)	// z[n-1] = w1>>s
+	RET
+
+X9b:	MOVQ $0, c+56(FP)
+	RET
+
+
+// func mulAddVWW(z, x []Word, y, r Word) (c Word)
+TEXT ·mulAddVWW(SB),NOSPLIT,$0
+	MOVQ z+0(FP), R10
+	MOVQ x+24(FP), R8
+	MOVQ y+48(FP), R9
+	MOVQ r+56(FP), CX	// c = r
+	MOVQ z_len+8(FP), R11
+	MOVQ $0, BX		// i = 0
+
+	CMPQ R11, $4
+	JL E5
+
+U5:	// i+4 <= n
+	// regular loop body unrolled 4x
+	MOVQ (0*8)(R8)(BX*8), AX
+	MULQ R9
+	ADDQ CX, AX
+	ADCQ $0, DX
+	MOVQ AX, (0*8)(R10)(BX*8)
+	MOVQ DX, CX
+	MOVQ (1*8)(R8)(BX*8), AX
+	MULQ R9
+	ADDQ CX, AX
+	ADCQ $0, DX
+	MOVQ AX, (1*8)(R10)(BX*8)
+	MOVQ DX, CX
+	MOVQ (2*8)(R8)(BX*8), AX
+	MULQ R9
+	ADDQ CX, AX
+	ADCQ $0, DX
+	MOVQ AX, (2*8)(R10)(BX*8)
+	MOVQ DX, CX
+	MOVQ (3*8)(R8)(BX*8), AX
+	MULQ R9
+	ADDQ CX, AX
+	ADCQ $0, DX
+	MOVQ AX, (3*8)(R10)(BX*8)
+	MOVQ DX, CX
+	ADDQ $4, BX		// i += 4
+
+	LEAQ 4(BX), DX
+	CMPQ DX, R11
+	JLE U5
+	JMP E5
+
+L5:	MOVQ (R8)(BX*8), AX
+	MULQ R9
+	ADDQ CX, AX
+	ADCQ $0, DX
+	MOVQ AX, (R10)(BX*8)
+	MOVQ DX, CX
+	ADDQ $1, BX		// i++
+
+E5:	CMPQ BX, R11		// i < n
+	JL L5
+
+	MOVQ CX, c+64(FP)
+	RET
+
+
+// func addMulVVW(z, x []Word, y Word) (c Word)
+TEXT ·addMulVVW(SB),NOSPLIT,$0
+	CMPB ·support_adx(SB), $1
+	JEQ adx
+	MOVQ z+0(FP), R10
+	MOVQ x+24(FP), R8
+	MOVQ y+48(FP), R9
+	MOVQ z_len+8(FP), R11
+	MOVQ $0, BX		// i = 0
+	MOVQ $0, CX		// c = 0
+	MOVQ R11, R12
+	ANDQ $-2, R12
+	CMPQ R11, $2
+	JAE A6
+	JMP E6
+
+A6:
+	MOVQ (R8)(BX*8), AX
+	MULQ R9
+	ADDQ (R10)(BX*8), AX
+	ADCQ $0, DX
+	ADDQ CX, AX
+	ADCQ $0, DX
+	MOVQ DX, CX
+	MOVQ AX, (R10)(BX*8)
+
+	MOVQ (8)(R8)(BX*8), AX
+	MULQ R9
+	ADDQ (8)(R10)(BX*8), AX
+	ADCQ $0, DX
+	ADDQ CX, AX
+	ADCQ $0, DX
+	MOVQ DX, CX
+	MOVQ AX, (8)(R10)(BX*8)
+
+	ADDQ $2, BX
+	CMPQ BX, R12
+	JL A6
+	JMP E6
+
+L6:	MOVQ (R8)(BX*8), AX
+	MULQ R9
+	ADDQ CX, AX
+	ADCQ $0, DX
+	ADDQ AX, (R10)(BX*8)
+	ADCQ $0, DX
+	MOVQ DX, CX
+	ADDQ $1, BX		// i++
+
+E6:	CMPQ BX, R11		// i < n
+	JL L6
+
+	MOVQ CX, c+56(FP)
+	RET
+
+adx:
+	MOVQ z_len+8(FP), R11
+	MOVQ z+0(FP), R10
+	MOVQ x+24(FP), R8
+	MOVQ y+48(FP), DX
+	MOVQ $0, BX   // i = 0
+	MOVQ $0, CX   // carry
+	CMPQ R11, $8
+	JAE  adx_loop_header
+	CMPQ BX, R11
+	JL adx_short
+	MOVQ CX, c+56(FP)
+	RET
+
+adx_loop_header:
+	MOVQ  R11, R13
+	ANDQ  $-8, R13
+adx_loop:
+	XORQ  R9, R9  // unset flags
+	MULXQ (R8), SI, DI
+	ADCXQ CX,SI
+	ADOXQ (R10), SI
+	MOVQ  SI,(R10)
+
+	MULXQ 8(R8), AX, CX
+	ADCXQ DI, AX
+	ADOXQ 8(R10), AX
+	MOVQ  AX, 8(R10)
+
+	MULXQ 16(R8), SI, DI
+	ADCXQ CX, SI
+	ADOXQ 16(R10), SI
+	MOVQ  SI, 16(R10)
+
+	MULXQ 24(R8), AX, CX
+	ADCXQ DI, AX
+	ADOXQ 24(R10), AX
+	MOVQ  AX, 24(R10)
+
+	MULXQ 32(R8), SI, DI
+	ADCXQ CX, SI
+	ADOXQ 32(R10), SI
+	MOVQ  SI, 32(R10)
+
+	MULXQ 40(R8), AX, CX
+	ADCXQ DI, AX
+	ADOXQ 40(R10), AX
+	MOVQ  AX, 40(R10)
+
+	MULXQ 48(R8), SI, DI
+	ADCXQ CX, SI
+	ADOXQ 48(R10), SI
+	MOVQ  SI, 48(R10)
+
+	MULXQ 56(R8), AX, CX
+	ADCXQ DI, AX
+	ADOXQ 56(R10), AX
+	MOVQ  AX, 56(R10)
+
+	ADCXQ R9, CX
+	ADOXQ R9, CX
+
+	ADDQ $64, R8
+	ADDQ $64, R10
+	ADDQ $8, BX
+
+	CMPQ BX, R13
+	JL adx_loop
+	MOVQ z+0(FP), R10
+	MOVQ x+24(FP), R8
+	CMPQ BX, R11
+	JL adx_short
+	MOVQ CX, c+56(FP)
+	RET
+
+adx_short:
+	MULXQ (R8)(BX*8), SI, DI
+	ADDQ CX, SI
+	ADCQ $0, DI
+	ADDQ SI, (R10)(BX*8)
+	ADCQ $0, DI
+	MOVQ DI, CX
+	ADDQ $1, BX		// i++
+
+	CMPQ BX, R11
+	JL adx_short
+
+	MOVQ CX, c+56(FP)
+	RET
+
+
+
diff --git a/contrib/go/_std_1.19/src/math/big/arith_decl.go b/contrib/go/_std_1.19/src/math/big/arith_decl.go
new file mode 100644
index 0000000000..301aa55f1a
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/big/arith_decl.go
@@ -0,0 +1,18 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !math_big_pure_go
+// +build !math_big_pure_go
+
+package big
+
+// implemented in arith_$GOARCH.s
+func addVV(z, x, y []Word) (c Word)
+func subVV(z, x, y []Word) (c Word)
+func addVW(z, x []Word, y Word) (c Word)
+func subVW(z, x []Word, y Word) (c Word)
+func shlVU(z, x []Word, s uint) (c Word)
+func shrVU(z, x []Word, s uint) (c Word)
+func mulAddVWW(z, x []Word, y, r Word) (c Word)
+func addMulVVW(z, x []Word, y Word) (c Word)
diff --git a/contrib/go/_std_1.18/src/math/big/decimal.go b/contrib/go/_std_1.19/src/math/big/decimal.go
index 716f03bfa4..716f03bfa4 100644
--- a/contrib/go/_std_1.18/src/math/big/decimal.go
+++ b/contrib/go/_std_1.19/src/math/big/decimal.go
diff --git a/contrib/go/_std_1.18/src/math/big/doc.go b/contrib/go/_std_1.19/src/math/big/doc.go
index 65ed019b74..65ed019b74 100644
--- a/contrib/go/_std_1.18/src/math/big/doc.go
+++ b/contrib/go/_std_1.19/src/math/big/doc.go
diff --git a/contrib/go/_std_1.19/src/math/big/float.go b/contrib/go/_std_1.19/src/math/big/float.go
new file mode 100644
index 0000000000..84666d817b
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/big/float.go
@@ -0,0 +1,1729 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements multi-precision floating-point numbers.
+// Like in the GNU MPFR library (https://www.mpfr.org/), operands
+// can be of mixed precision. Unlike MPFR, the rounding mode is
+// not specified with each operation, but with each operand. The
+// rounding mode of the result operand determines the rounding
+// mode of an operation. This is a from-scratch implementation.
+
+package big
+
+import (
+	"fmt"
+	"math"
+	"math/bits"
+)
+
+const debugFloat = false // enable for debugging
+
+// A nonzero finite Float represents a multi-precision floating point number
+//
+//	sign × mantissa × 2**exponent
+//
+// with 0.5 <= mantissa < 1.0, and MinExp <= exponent <= MaxExp.
+// A Float may also be zero (+0, -0) or infinite (+Inf, -Inf).
+// All Floats are ordered, and the ordering of two Floats x and y
+// is defined by x.Cmp(y).
+//
+// Each Float value also has a precision, rounding mode, and accuracy.
+// The precision is the maximum number of mantissa bits available to
+// represent the value. The rounding mode specifies how a result should
+// be rounded to fit into the mantissa bits, and accuracy describes the
+// rounding error with respect to the exact result.
+//
+// Unless specified otherwise, all operations (including setters) that
+// specify a *Float variable for the result (usually via the receiver
+// with the exception of MantExp), round the numeric result according
+// to the precision and rounding mode of the result variable.
+//
+// If the provided result precision is 0 (see below), it is set to the
+// precision of the argument with the largest precision value before any
+// rounding takes place, and the rounding mode remains unchanged. Thus,
+// uninitialized Floats provided as result arguments will have their
+// precision set to a reasonable value determined by the operands, and
+// their mode is the zero value for RoundingMode (ToNearestEven).
+//
+// By setting the desired precision to 24 or 53 and using matching rounding
+// mode (typically ToNearestEven), Float operations produce the same results
+// as the corresponding float32 or float64 IEEE-754 arithmetic for operands
+// that correspond to normal (i.e., not denormal) float32 or float64 numbers.
+// Exponent underflow and overflow lead to a 0 or an Infinity for different
+// values than IEEE-754 because Float exponents have a much larger range.
+//
+// The zero (uninitialized) value for a Float is ready to use and represents
+// the number +0.0 exactly, with precision 0 and rounding mode ToNearestEven.
+//
+// Operations always take pointer arguments (*Float) rather
+// than Float values, and each unique Float value requires
+// its own unique *Float pointer. To "copy" a Float value,
+// an existing (or newly allocated) Float must be set to
+// a new value using the Float.Set method; shallow copies
+// of Floats are not supported and may lead to errors.
+type Float struct {
+	prec uint32
+	mode RoundingMode
+	acc  Accuracy
+	form form
+	neg  bool
+	mant nat
+	exp  int32
+}
+
+// An ErrNaN panic is raised by a Float operation that would lead to
+// a NaN under IEEE-754 rules. An ErrNaN implements the error interface.
+type ErrNaN struct {
+	msg string
+}
+
+func (err ErrNaN) Error() string {
+	return err.msg
+}
+
+// NewFloat allocates and returns a new Float set to x,
+// with precision 53 and rounding mode ToNearestEven.
+// NewFloat panics with ErrNaN if x is a NaN.
+func NewFloat(x float64) *Float {
+	if math.IsNaN(x) {
+		panic(ErrNaN{"NewFloat(NaN)"})
+	}
+	return new(Float).SetFloat64(x)
+}
+
+// Exponent and precision limits.
+const (
+	MaxExp  = math.MaxInt32  // largest supported exponent
+	MinExp  = math.MinInt32  // smallest supported exponent
+	MaxPrec = math.MaxUint32 // largest (theoretically) supported precision; likely memory-limited
+)
+
+// Internal representation: The mantissa bits x.mant of a nonzero finite
+// Float x are stored in a nat slice long enough to hold up to x.prec bits;
+// the slice may (but doesn't have to) be shorter if the mantissa contains
+// trailing 0 bits. x.mant is normalized if the msb of x.mant == 1 (i.e.,
+// the msb is shifted all the way "to the left"). Thus, if the mantissa has
+// trailing 0 bits or x.prec is not a multiple of the Word size _W,
+// x.mant[0] has trailing zero bits. The msb of the mantissa corresponds
+// to the value 0.5; the exponent x.exp shifts the binary point as needed.
+//
+// A zero or non-finite Float x ignores x.mant and x.exp.
+//
+// x                 form      neg      mant         exp
+// ----------------------------------------------------------
+// ±0                zero      sign     -            -
+// 0 < |x| < +Inf    finite    sign     mantissa     exponent
+// ±Inf              inf       sign     -            -
+
+// A form value describes the internal representation.
+type form byte
+
+// The form value order is relevant - do not change!
+const (
+	zero form = iota
+	finite
+	inf
+)
+
+// RoundingMode determines how a Float value is rounded to the
+// desired precision. Rounding may change the Float value; the
+// rounding error is described by the Float's Accuracy.
+type RoundingMode byte
+
+// These constants define supported rounding modes.
+const (
+	ToNearestEven RoundingMode = iota // == IEEE 754-2008 roundTiesToEven
+	ToNearestAway                     // == IEEE 754-2008 roundTiesToAway
+	ToZero                            // == IEEE 754-2008 roundTowardZero
+	AwayFromZero                      // no IEEE 754-2008 equivalent
+	ToNegativeInf                     // == IEEE 754-2008 roundTowardNegative
+	ToPositiveInf                     // == IEEE 754-2008 roundTowardPositive
+)
+
+//go:generate stringer -type=RoundingMode
+
+// Accuracy describes the rounding error produced by the most recent
+// operation that generated a Float value, relative to the exact value.
+type Accuracy int8
+
+// Constants describing the Accuracy of a Float.
+const (
+	Below Accuracy = -1
+	Exact Accuracy = 0
+	Above Accuracy = +1
+)
+
+//go:generate stringer -type=Accuracy
+
+// SetPrec sets z's precision to prec and returns the (possibly) rounded
+// value of z. Rounding occurs according to z's rounding mode if the mantissa
+// cannot be represented in prec bits without loss of precision.
+// SetPrec(0) maps all finite values to ±0; infinite values remain unchanged.
+// If prec > MaxPrec, it is set to MaxPrec.
+func (z *Float) SetPrec(prec uint) *Float {
+	z.acc = Exact // optimistically assume no rounding is needed
+
+	// special case
+	if prec == 0 {
+		z.prec = 0
+		if z.form == finite {
+			// truncate z to 0
+			z.acc = makeAcc(z.neg)
+			z.form = zero
+		}
+		return z
+	}
+
+	// general case
+	if prec > MaxPrec {
+		prec = MaxPrec
+	}
+	old := z.prec
+	z.prec = uint32(prec)
+	if z.prec < old {
+		z.round(0)
+	}
+	return z
+}
+
+func makeAcc(above bool) Accuracy {
+	if above {
+		return Above
+	}
+	return Below
+}
+
+// SetMode sets z's rounding mode to mode and returns an exact z.
+// z remains unchanged otherwise.
+// z.SetMode(z.Mode()) is a cheap way to set z's accuracy to Exact.
+func (z *Float) SetMode(mode RoundingMode) *Float {
+	z.mode = mode
+	z.acc = Exact
+	return z
+}
+
+// Prec returns the mantissa precision of x in bits.
+// The result may be 0 for |x| == 0 and |x| == Inf.
+func (x *Float) Prec() uint {
+	return uint(x.prec)
+}
+
+// MinPrec returns the minimum precision required to represent x exactly
+// (i.e., the smallest prec before x.SetPrec(prec) would start rounding x).
+// The result is 0 for |x| == 0 and |x| == Inf.
+func (x *Float) MinPrec() uint {
+	if x.form != finite {
+		return 0
+	}
+	return uint(len(x.mant))*_W - x.mant.trailingZeroBits()
+}
+
+// Mode returns the rounding mode of x.
+func (x *Float) Mode() RoundingMode {
+	return x.mode
+}
+
+// Acc returns the accuracy of x produced by the most recent
+// operation, unless explicitly documented otherwise by that
+// operation.
+func (x *Float) Acc() Accuracy {
+	return x.acc
+}
+
+// Sign returns:
+//
+//	-1 if x <   0
+//	 0 if x is ±0
+//	+1 if x >   0
+func (x *Float) Sign() int {
+	if debugFloat {
+		x.validate()
+	}
+	if x.form == zero {
+		return 0
+	}
+	if x.neg {
+		return -1
+	}
+	return 1
+}
+
+// MantExp breaks x into its mantissa and exponent components
+// and returns the exponent. If a non-nil mant argument is
+// provided its value is set to the mantissa of x, with the
+// same precision and rounding mode as x. The components
+// satisfy x == mant × 2**exp, with 0.5 <= |mant| < 1.0.
+// Calling MantExp with a nil argument is an efficient way to
+// get the exponent of the receiver.
+//
+// Special cases are:
+//
+//	(  ±0).MantExp(mant) = 0, with mant set to   ±0
+//	(±Inf).MantExp(mant) = 0, with mant set to ±Inf
+//
+// x and mant may be the same in which case x is set to its
+// mantissa value.
+func (x *Float) MantExp(mant *Float) (exp int) {
+	if debugFloat {
+		x.validate()
+	}
+	if x.form == finite {
+		exp = int(x.exp)
+	}
+	if mant != nil {
+		mant.Copy(x)
+		if mant.form == finite {
+			mant.exp = 0
+		}
+	}
+	return
+}
+
+func (z *Float) setExpAndRound(exp int64, sbit uint) {
+	if exp < MinExp {
+		// underflow
+		z.acc = makeAcc(z.neg)
+		z.form = zero
+		return
+	}
+
+	if exp > MaxExp {
+		// overflow
+		z.acc = makeAcc(!z.neg)
+		z.form = inf
+		return
+	}
+
+	z.form = finite
+	z.exp = int32(exp)
+	z.round(sbit)
+}
+
+// SetMantExp sets z to mant × 2**exp and returns z.
+// The result z has the same precision and rounding mode
+// as mant. SetMantExp is an inverse of MantExp but does
+// not require 0.5 <= |mant| < 1.0. Specifically, for a
+// given x of type *Float, SetMantExp relates to MantExp
+// as follows:
+//
+//	mant := new(Float)
+//	new(Float).SetMantExp(mant, x.MantExp(mant)).Cmp(x) == 0
+//
+// Special cases are:
+//
+//	z.SetMantExp(  ±0, exp) =   ±0
+//	z.SetMantExp(±Inf, exp) = ±Inf
+//
+// z and mant may be the same in which case z's exponent
+// is set to exp.
+func (z *Float) SetMantExp(mant *Float, exp int) *Float {
+	if debugFloat {
+		z.validate()
+		mant.validate()
+	}
+	z.Copy(mant)
+
+	if z.form == finite {
+		// 0 < |mant| < +Inf
+		z.setExpAndRound(int64(z.exp)+int64(exp), 0)
+	}
+	return z
+}
+
+// Signbit reports whether x is negative or negative zero.
+func (x *Float) Signbit() bool {
+	return x.neg
+}
+
+// IsInf reports whether x is +Inf or -Inf.
+func (x *Float) IsInf() bool {
+	return x.form == inf
+}
+
+// IsInt reports whether x is an integer.
+// ±Inf values are not integers.
+func (x *Float) IsInt() bool {
+	if debugFloat {
+		x.validate()
+	}
+	// special cases
+	if x.form != finite {
+		return x.form == zero
+	}
+	// x.form == finite
+	if x.exp <= 0 {
+		return false
+	}
+	// x.exp > 0
+	return x.prec <= uint32(x.exp) || x.MinPrec() <= uint(x.exp) // not enough bits for fractional mantissa
+}
+
+// debugging support
+func (x *Float) validate() {
+	if !debugFloat {
+		// avoid performance bugs
+		panic("validate called but debugFloat is not set")
+	}
+	if x.form != finite {
+		return
+	}
+	m := len(x.mant)
+	if m == 0 {
+		panic("nonzero finite number with empty mantissa")
+	}
+	const msb = 1 << (_W - 1)
+	if x.mant[m-1]&msb == 0 {
+		panic(fmt.Sprintf("msb not set in last word %#x of %s", x.mant[m-1], x.Text('p', 0)))
+	}
+	if x.prec == 0 {
+		panic("zero precision finite number")
+	}
+}
+
+// round rounds z according to z.mode to z.prec bits and sets z.acc accordingly.
+// sbit must be 0 or 1 and summarizes any "sticky bit" information one might
+// have before calling round. z's mantissa must be normalized (with the msb set)
+// or empty.
+//
+// CAUTION: The rounding modes ToNegativeInf, ToPositiveInf are affected by the
+// sign of z. For correct rounding, the sign of z must be set correctly before
+// calling round.
+func (z *Float) round(sbit uint) {
+	if debugFloat {
+		z.validate()
+	}
+
+	z.acc = Exact
+	if z.form != finite {
+		// ±0 or ±Inf => nothing left to do
+		return
+	}
+	// z.form == finite && len(z.mant) > 0
+	// m > 0 implies z.prec > 0 (checked by validate)
+
+	m := uint32(len(z.mant)) // present mantissa length in words
+	bits := m * _W           // present mantissa bits; bits > 0
+	if bits <= z.prec {
+		// mantissa fits => nothing to do
+		return
+	}
+	// bits > z.prec
+
+	// Rounding is based on two bits: the rounding bit (rbit) and the
+	// sticky bit (sbit). The rbit is the bit immediately before the
+	// z.prec leading mantissa bits (the "0.5"). The sbit is set if any
+	// of the bits before the rbit are set (the "0.25", "0.125", etc.):
+	//
+	//   rbit  sbit  => "fractional part"
+	//
+	//   0     0        == 0
+	//   0     1        >  0  , < 0.5
+	//   1     0        == 0.5
+	//   1     1        >  0.5, < 1.0
+
+	// bits > z.prec: mantissa too large => round
+	r := uint(bits - z.prec - 1) // rounding bit position; r >= 0
+	rbit := z.mant.bit(r) & 1    // rounding bit; be safe and ensure it's a single bit
+	// The sticky bit is only needed for rounding ToNearestEven
+	// or when the rounding bit is zero. Avoid computation otherwise.
+	if sbit == 0 && (rbit == 0 || z.mode == ToNearestEven) {
+		sbit = z.mant.sticky(r)
+	}
+	sbit &= 1 // be safe and ensure it's a single bit
+
+	// cut off extra words
+	n := (z.prec + (_W - 1)) / _W // mantissa length in words for desired precision
+	if m > n {
+		copy(z.mant, z.mant[m-n:]) // move n last words to front
+		z.mant = z.mant[:n]
+	}
+
+	// determine number of trailing zero bits (ntz) and compute lsb mask of mantissa's least-significant word
+	ntz := n*_W - z.prec // 0 <= ntz < _W
+	lsb := Word(1) << ntz
+
+	// round if result is inexact
+	if rbit|sbit != 0 {
+		// Make rounding decision: The result mantissa is truncated ("rounded down")
+		// by default. Decide if we need to increment, or "round up", the (unsigned)
+		// mantissa.
+		inc := false
+		switch z.mode {
+		case ToNegativeInf:
+			inc = z.neg
+		case ToZero:
+			// nothing to do
+		case ToNearestEven:
+			inc = rbit != 0 && (sbit != 0 || z.mant[0]&lsb != 0)
+		case ToNearestAway:
+			inc = rbit != 0
+		case AwayFromZero:
+			inc = true
+		case ToPositiveInf:
+			inc = !z.neg
+		default:
+			panic("unreachable")
+		}
+
+		// A positive result (!z.neg) is Above the exact result if we increment,
+		// and it's Below if we truncate (Exact results require no rounding).
+		// For a negative result (z.neg) it is exactly the opposite.
+		z.acc = makeAcc(inc != z.neg)
+
+		if inc {
+			// add 1 to mantissa
+			if addVW(z.mant, z.mant, lsb) != 0 {
+				// mantissa overflow => adjust exponent
+				if z.exp >= MaxExp {
+					// exponent overflow
+					z.form = inf
+					return
+				}
+				z.exp++
+				// adjust mantissa: divide by 2 to compensate for exponent adjustment
+				shrVU(z.mant, z.mant, 1)
+				// set msb == carry == 1 from the mantissa overflow above
+				const msb = 1 << (_W - 1)
+				z.mant[n-1] |= msb
+			}
+		}
+	}
+
+	// zero out trailing bits in least-significant word
+	z.mant[0] &^= lsb - 1
+
+	if debugFloat {
+		z.validate()
+	}
+}
+
+func (z *Float) setBits64(neg bool, x uint64) *Float {
+	if z.prec == 0 {
+		z.prec = 64
+	}
+	z.acc = Exact
+	z.neg = neg
+	if x == 0 {
+		z.form = zero
+		return z
+	}
+	// x != 0
+	z.form = finite
+	s := bits.LeadingZeros64(x)
+	z.mant = z.mant.setUint64(x << uint(s))
+	z.exp = int32(64 - s) // always fits
+	if z.prec < 64 {
+		z.round(0)
+	}
+	return z
+}
+
+// SetUint64 sets z to the (possibly rounded) value of x and returns z.
+// If z's precision is 0, it is changed to 64 (and rounding will have
+// no effect).
+func (z *Float) SetUint64(x uint64) *Float {
+	return z.setBits64(false, x)
+}
+
+// SetInt64 sets z to the (possibly rounded) value of x and returns z.
+// If z's precision is 0, it is changed to 64 (and rounding will have
+// no effect).
+func (z *Float) SetInt64(x int64) *Float {
+	u := x
+	if u < 0 {
+		u = -u
+	}
+	// We cannot simply call z.SetUint64(uint64(u)) and change
+	// the sign afterwards because the sign affects rounding.
+	return z.setBits64(x < 0, uint64(u))
+}
+
+// SetFloat64 sets z to the (possibly rounded) value of x and returns z.
+// If z's precision is 0, it is changed to 53 (and rounding will have
+// no effect). SetFloat64 panics with ErrNaN if x is a NaN.
+func (z *Float) SetFloat64(x float64) *Float {
+	if z.prec == 0 {
+		z.prec = 53
+	}
+	if math.IsNaN(x) {
+		panic(ErrNaN{"Float.SetFloat64(NaN)"})
+	}
+	z.acc = Exact
+	z.neg = math.Signbit(x) // handle -0, -Inf correctly
+	if x == 0 {
+		z.form = zero
+		return z
+	}
+	if math.IsInf(x, 0) {
+		z.form = inf
+		return z
+	}
+	// normalized x != 0
+	z.form = finite
+	fmant, exp := math.Frexp(x) // get normalized mantissa
+	z.mant = z.mant.setUint64(1<<63 | math.Float64bits(fmant)<<11)
+	z.exp = int32(exp) // always fits
+	if z.prec < 53 {
+		z.round(0)
+	}
+	return z
+}
+
+// fnorm normalizes mantissa m by shifting it to the left
+// such that the msb of the most-significant word (msw) is 1.
+// It returns the shift amount. It assumes that len(m) != 0.
+func fnorm(m nat) int64 {
+	if debugFloat && (len(m) == 0 || m[len(m)-1] == 0) {
+		panic("msw of mantissa is 0")
+	}
+	s := nlz(m[len(m)-1])
+	if s > 0 {
+		c := shlVU(m, m, s)
+		if debugFloat && c != 0 {
+			panic("nlz or shlVU incorrect")
+		}
+	}
+	return int64(s)
+}
+
+// SetInt sets z to the (possibly rounded) value of x and returns z.
+// If z's precision is 0, it is changed to the larger of x.BitLen()
+// or 64 (and rounding will have no effect).
+func (z *Float) SetInt(x *Int) *Float {
+	// TODO(gri) can be more efficient if z.prec > 0
+	// but small compared to the size of x, or if there
+	// are many trailing 0's.
+	bits := uint32(x.BitLen())
+	if z.prec == 0 {
+		z.prec = umax32(bits, 64)
+	}
+	z.acc = Exact
+	z.neg = x.neg
+	if len(x.abs) == 0 {
+		z.form = zero
+		return z
+	}
+	// x != 0
+	z.mant = z.mant.set(x.abs)
+	fnorm(z.mant)
+	z.setExpAndRound(int64(bits), 0)
+	return z
+}
+
+// SetRat sets z to the (possibly rounded) value of x and returns z.
+// If z's precision is 0, it is changed to the largest of a.BitLen(),
+// b.BitLen(), or 64; with x = a/b.
+func (z *Float) SetRat(x *Rat) *Float {
+	if x.IsInt() {
+		return z.SetInt(x.Num())
+	}
+	var a, b Float
+	a.SetInt(x.Num())
+	b.SetInt(x.Denom())
+	if z.prec == 0 {
+		z.prec = umax32(a.prec, b.prec)
+	}
+	return z.Quo(&a, &b)
+}
+
+// SetInf sets z to the infinite Float -Inf if signbit is
+// set, or +Inf if signbit is not set, and returns z. The
+// precision of z is unchanged and the result is always
+// Exact.
+func (z *Float) SetInf(signbit bool) *Float {
+	z.acc = Exact
+	z.form = inf
+	z.neg = signbit
+	return z
+}
+
+// Set sets z to the (possibly rounded) value of x and returns z.
+// If z's precision is 0, it is changed to the precision of x
+// before setting z (and rounding will have no effect).
+// Rounding is performed according to z's precision and rounding
+// mode; and z's accuracy reports the result error relative to the
+// exact (not rounded) result.
+func (z *Float) Set(x *Float) *Float {
+	if debugFloat {
+		x.validate()
+	}
+	z.acc = Exact
+	if z != x {
+		z.form = x.form
+		z.neg = x.neg
+		if x.form == finite {
+			z.exp = x.exp
+			z.mant = z.mant.set(x.mant)
+		}
+		if z.prec == 0 {
+			z.prec = x.prec
+		} else if z.prec < x.prec {
+			z.round(0)
+		}
+	}
+	return z
+}
+
+// Copy sets z to x, with the same precision, rounding mode, and
+// accuracy as x, and returns z. x is not changed even if z and
+// x are the same.
+func (z *Float) Copy(x *Float) *Float {
+	if debugFloat {
+		x.validate()
+	}
+	if z != x {
+		z.prec = x.prec
+		z.mode = x.mode
+		z.acc = x.acc
+		z.form = x.form
+		z.neg = x.neg
+		if z.form == finite {
+			z.mant = z.mant.set(x.mant)
+			z.exp = x.exp
+		}
+	}
+	return z
+}
+
+// msb32 returns the 32 most significant bits of x.
+func msb32(x nat) uint32 {
+	i := len(x) - 1
+	if i < 0 {
+		return 0
+	}
+	if debugFloat && x[i]&(1<<(_W-1)) == 0 {
+		panic("x not normalized")
+	}
+	switch _W {
+	case 32:
+		return uint32(x[i])
+	case 64:
+		return uint32(x[i] >> 32)
+	}
+	panic("unreachable")
+}
+
+// msb64 returns the 64 most significant bits of x.
+func msb64(x nat) uint64 {
+	i := len(x) - 1
+	if i < 0 {
+		return 0
+	}
+	if debugFloat && x[i]&(1<<(_W-1)) == 0 {
+		panic("x not normalized")
+	}
+	switch _W {
+	case 32:
+		v := uint64(x[i]) << 32
+		if i > 0 {
+			v |= uint64(x[i-1])
+		}
+		return v
+	case 64:
+		return uint64(x[i])
+	}
+	panic("unreachable")
+}
+
+// Uint64 returns the unsigned integer resulting from truncating x
+// towards zero. If 0 <= x <= math.MaxUint64, the result is Exact
+// if x is an integer and Below otherwise.
+// The result is (0, Above) for x < 0, and (math.MaxUint64, Below)
+// for x > math.MaxUint64.
+func (x *Float) Uint64() (uint64, Accuracy) {
+	if debugFloat {
+		x.validate()
+	}
+
+	switch x.form {
+	case finite:
+		if x.neg {
+			return 0, Above
+		}
+		// 0 < x < +Inf
+		if x.exp <= 0 {
+			// 0 < x < 1
+			return 0, Below
+		}
+		// 1 <= x < Inf
+		if x.exp <= 64 {
+			// u = trunc(x) fits into a uint64
+			u := msb64(x.mant) >> (64 - uint32(x.exp))
+			if x.MinPrec() <= 64 {
+				return u, Exact
+			}
+			return u, Below // x truncated
+		}
+		// x too large
+		return math.MaxUint64, Below
+
+	case zero:
+		return 0, Exact
+
+	case inf:
+		if x.neg {
+			return 0, Above
+		}
+		return math.MaxUint64, Below
+	}
+
+	panic("unreachable")
+}
+
+// Int64 returns the integer resulting from truncating x towards zero.
+// If math.MinInt64 <= x <= math.MaxInt64, the result is Exact if x is
+// an integer, and Above (x < 0) or Below (x > 0) otherwise.
+// The result is (math.MinInt64, Above) for x < math.MinInt64,
+// and (math.MaxInt64, Below) for x > math.MaxInt64.
+func (x *Float) Int64() (int64, Accuracy) {
+	if debugFloat {
+		x.validate()
+	}
+
+	switch x.form {
+	case finite:
+		// 0 < |x| < +Inf
+		acc := makeAcc(x.neg)
+		if x.exp <= 0 {
+			// 0 < |x| < 1
+			return 0, acc
+		}
+		// x.exp > 0
+
+		// 1 <= |x| < +Inf
+		if x.exp <= 63 {
+			// i = trunc(x) fits into an int64 (excluding math.MinInt64)
+			i := int64(msb64(x.mant) >> (64 - uint32(x.exp)))
+			if x.neg {
+				i = -i
+			}
+			if x.MinPrec() <= uint(x.exp) {
+				return i, Exact
+			}
+			return i, acc // x truncated
+		}
+		if x.neg {
+			// check for special case x == math.MinInt64 (i.e., x == -(0.5 << 64))
+			if x.exp == 64 && x.MinPrec() == 1 {
+				acc = Exact
+			}
+			return math.MinInt64, acc
+		}
+		// x too large
+		return math.MaxInt64, Below
+
+	case zero:
+		return 0, Exact
+
+	case inf:
+		if x.neg {
+			return math.MinInt64, Above
+		}
+		return math.MaxInt64, Below
+	}
+
+	panic("unreachable")
+}
+
+// Float32 returns the float32 value nearest to x. If x is too small to be
+// represented by a float32 (|x| < math.SmallestNonzeroFloat32), the result
+// is (0, Below) or (-0, Above), respectively, depending on the sign of x.
+// If x is too large to be represented by a float32 (|x| > math.MaxFloat32),
+// the result is (+Inf, Above) or (-Inf, Below), depending on the sign of x.
+func (x *Float) Float32() (float32, Accuracy) {
+	if debugFloat {
+		x.validate()
+	}
+
+	switch x.form {
+	case finite:
+		// 0 < |x| < +Inf
+
+		const (
+			fbits = 32                //        float size
+			mbits = 23                //        mantissa size (excluding implicit msb)
+			ebits = fbits - mbits - 1 //     8  exponent size
+			bias  = 1<<(ebits-1) - 1  //   127  exponent bias
+			dmin  = 1 - bias - mbits  //  -149  smallest unbiased exponent (denormal)
+			emin  = 1 - bias          //  -126  smallest unbiased exponent (normal)
+			emax  = bias              //   127  largest unbiased exponent (normal)
+		)
+
+		// Float mantissa m is 0.5 <= m < 1.0; compute exponent e for float32 mantissa.
+		e := x.exp - 1 // exponent for normal mantissa m with 1.0 <= m < 2.0
+
+		// Compute precision p for float32 mantissa.
+		// If the exponent is too small, we have a denormal number before
+		// rounding and fewer than p mantissa bits of precision available
+		// (the exponent remains fixed but the mantissa gets shifted right).
+		p := mbits + 1 // precision of normal float
+		if e < emin {
+			// recompute precision
+			p = mbits + 1 - emin + int(e)
+			// If p == 0, the mantissa of x is shifted so much to the right
+			// that its msb falls immediately to the right of the float32
+			// mantissa space. In other words, if the smallest denormal is
+			// considered "1.0", for p == 0, the mantissa value m is >= 0.5.
+			// If m > 0.5, it is rounded up to 1.0; i.e., the smallest denormal.
+			// If m == 0.5, it is rounded down to even, i.e., 0.0.
+			// If p < 0, the mantissa value m is <= "0.25" which is never rounded up.
+			if p < 0 /* m <= 0.25 */ || p == 0 && x.mant.sticky(uint(len(x.mant))*_W-1) == 0 /* m == 0.5 */ {
+				// underflow to ±0
+				if x.neg {
+					var z float32
+					return -z, Above
+				}
+				return 0.0, Below
+			}
+			// otherwise, round up
+			// We handle p == 0 explicitly because it's easy and because
+			// Float.round doesn't support rounding to 0 bits of precision.
+			if p == 0 {
+				if x.neg {
+					return -math.SmallestNonzeroFloat32, Below
+				}
+				return math.SmallestNonzeroFloat32, Above
+			}
+		}
+		// p > 0
+
+		// round
+		var r Float
+		r.prec = uint32(p)
+		r.Set(x)
+		e = r.exp - 1
+
+		// Rounding may have caused r to overflow to ±Inf
+		// (rounding never causes underflows to 0).
+		// If the exponent is too large, also overflow to ±Inf.
+		if r.form == inf || e > emax {
+			// overflow
+			if x.neg {
+				return float32(math.Inf(-1)), Below
+			}
+			return float32(math.Inf(+1)), Above
+		}
+		// e <= emax
+
+		// Determine sign, biased exponent, and mantissa.
+		var sign, bexp, mant uint32
+		if x.neg {
+			sign = 1 << (fbits - 1)
+		}
+
+		// Rounding may have caused a denormal number to
+		// become normal. Check again.
+		if e < emin {
+			// denormal number: recompute precision
+			// Since rounding may have at best increased precision
+			// and we have eliminated p <= 0 early, we know p > 0.
+			// bexp == 0 for denormals
+			p = mbits + 1 - emin + int(e)
+			mant = msb32(r.mant) >> uint(fbits-p)
+		} else {
+			// normal number: emin <= e <= emax
+			bexp = uint32(e+bias) << mbits
+			mant = msb32(r.mant) >> ebits & (1<<mbits - 1) // cut off msb (implicit 1 bit)
+		}
+
+		return math.Float32frombits(sign | bexp | mant), r.acc
+
+	case zero:
+		if x.neg {
+			var z float32
+			return -z, Exact
+		}
+		return 0.0, Exact
+
+	case inf:
+		if x.neg {
+			return float32(math.Inf(-1)), Exact
+		}
+		return float32(math.Inf(+1)), Exact
+	}
+
+	panic("unreachable")
+}
+
+// Float64 returns the float64 value nearest to x. If x is too small to be
+// represented by a float64 (|x| < math.SmallestNonzeroFloat64), the result
+// is (0, Below) or (-0, Above), respectively, depending on the sign of x.
+// If x is too large to be represented by a float64 (|x| > math.MaxFloat64),
+// the result is (+Inf, Above) or (-Inf, Below), depending on the sign of x.
+func (x *Float) Float64() (float64, Accuracy) {
+	if debugFloat {
+		x.validate()
+	}
+
+	switch x.form {
+	case finite:
+		// 0 < |x| < +Inf
+
+		const (
+			fbits = 64                //        float size
+			mbits = 52                //        mantissa size (excluding implicit msb)
+			ebits = fbits - mbits - 1 //    11  exponent size
+			bias  = 1<<(ebits-1) - 1  //  1023  exponent bias
+			dmin  = 1 - bias - mbits  // -1074  smallest unbiased exponent (denormal)
+			emin  = 1 - bias          // -1022  smallest unbiased exponent (normal)
+			emax  = bias              //  1023  largest unbiased exponent (normal)
+		)
+
+		// Float mantissa m is 0.5 <= m < 1.0; compute exponent e for float64 mantissa.
+		e := x.exp - 1 // exponent for normal mantissa m with 1.0 <= m < 2.0
+
+		// Compute precision p for float64 mantissa.
+		// If the exponent is too small, we have a denormal number before
+		// rounding and fewer than p mantissa bits of precision available
+		// (the exponent remains fixed but the mantissa gets shifted right).
+		p := mbits + 1 // precision of normal float
+		if e < emin {
+			// recompute precision
+			p = mbits + 1 - emin + int(e)
+			// If p == 0, the mantissa of x is shifted so much to the right
+			// that its msb falls immediately to the right of the float64
+			// mantissa space. In other words, if the smallest denormal is
+			// considered "1.0", for p == 0, the mantissa value m is >= 0.5.
+			// If m > 0.5, it is rounded up to 1.0; i.e., the smallest denormal.
+			// If m == 0.5, it is rounded down to even, i.e., 0.0.
+			// If p < 0, the mantissa value m is <= "0.25" which is never rounded up.
+			if p < 0 /* m <= 0.25 */ || p == 0 && x.mant.sticky(uint(len(x.mant))*_W-1) == 0 /* m == 0.5 */ {
+				// underflow to ±0
+				if x.neg {
+					var z float64
+					return -z, Above
+				}
+				return 0.0, Below
+			}
+			// otherwise, round up
+			// We handle p == 0 explicitly because it's easy and because
+			// Float.round doesn't support rounding to 0 bits of precision.
+			if p == 0 {
+				if x.neg {
+					return -math.SmallestNonzeroFloat64, Below
+				}
+				return math.SmallestNonzeroFloat64, Above
+			}
+		}
+		// p > 0
+
+		// round
+		var r Float
+		r.prec = uint32(p)
+		r.Set(x)
+		e = r.exp - 1
+
+		// Rounding may have caused r to overflow to ±Inf
+		// (rounding never causes underflows to 0).
+		// If the exponent is too large, also overflow to ±Inf.
+		if r.form == inf || e > emax {
+			// overflow
+			if x.neg {
+				return math.Inf(-1), Below
+			}
+			return math.Inf(+1), Above
+		}
+		// e <= emax
+
+		// Determine sign, biased exponent, and mantissa.
+		var sign, bexp, mant uint64
+		if x.neg {
+			sign = 1 << (fbits - 1)
+		}
+
+		// Rounding may have caused a denormal number to
+		// become normal. Check again.
+		if e < emin {
+			// denormal number: recompute precision
+			// Since rounding may have at best increased precision
+			// and we have eliminated p <= 0 early, we know p > 0.
+			// bexp == 0 for denormals
+			p = mbits + 1 - emin + int(e)
+			mant = msb64(r.mant) >> uint(fbits-p)
+		} else {
+			// normal number: emin <= e <= emax
+			bexp = uint64(e+bias) << mbits
+			mant = msb64(r.mant) >> ebits & (1<<mbits - 1) // cut off msb (implicit 1 bit)
+		}
+
+		return math.Float64frombits(sign | bexp | mant), r.acc
+
+	case zero:
+		if x.neg {
+			var z float64
+			return -z, Exact
+		}
+		return 0.0, Exact
+
+	case inf:
+		if x.neg {
+			return math.Inf(-1), Exact
+		}
+		return math.Inf(+1), Exact
+	}
+
+	panic("unreachable")
+}
+
+// Int returns the result of truncating x towards zero;
+// or nil if x is an infinity.
+// The result is Exact if x.IsInt(); otherwise it is Below
+// for x > 0, and Above for x < 0.
+// If a non-nil *Int argument z is provided, Int stores
+// the result in z instead of allocating a new Int.
+func (x *Float) Int(z *Int) (*Int, Accuracy) {
+	if debugFloat {
+		x.validate()
+	}
+
+	if z == nil && x.form <= finite {
+		z = new(Int)
+	}
+
+	switch x.form {
+	case finite:
+		// 0 < |x| < +Inf
+		acc := makeAcc(x.neg)
+		if x.exp <= 0 {
+			// 0 < |x| < 1
+			return z.SetInt64(0), acc
+		}
+		// x.exp > 0
+
+		// 1 <= |x| < +Inf
+		// determine minimum required precision for x
+		allBits := uint(len(x.mant)) * _W
+		exp := uint(x.exp)
+		if x.MinPrec() <= exp {
+			acc = Exact
+		}
+		// shift mantissa as needed
+		if z == nil {
+			z = new(Int)
+		}
+		z.neg = x.neg
+		switch {
+		case exp > allBits:
+			z.abs = z.abs.shl(x.mant, exp-allBits)
+		default:
+			z.abs = z.abs.set(x.mant)
+		case exp < allBits:
+			z.abs = z.abs.shr(x.mant, allBits-exp)
+		}
+		return z, acc
+
+	case zero:
+		return z.SetInt64(0), Exact
+
+	case inf:
+		return nil, makeAcc(x.neg)
+	}
+
+	panic("unreachable")
+}
+
+// Rat returns the rational number corresponding to x;
+// or nil if x is an infinity.
+// The result is Exact if x is not an Inf.
+// If a non-nil *Rat argument z is provided, Rat stores
+// the result in z instead of allocating a new Rat.
+func (x *Float) Rat(z *Rat) (*Rat, Accuracy) {
+	if debugFloat {
+		x.validate()
+	}
+
+	if z == nil && x.form <= finite {
+		z = new(Rat)
+	}
+
+	switch x.form {
+	case finite:
+		// 0 < |x| < +Inf
+		allBits := int32(len(x.mant)) * _W
+		// build up numerator and denominator
+		z.a.neg = x.neg
+		switch {
+		case x.exp > allBits:
+			z.a.abs = z.a.abs.shl(x.mant, uint(x.exp-allBits))
+			z.b.abs = z.b.abs[:0] // == 1 (see Rat)
+			// z already in normal form
+		default:
+			z.a.abs = z.a.abs.set(x.mant)
+			z.b.abs = z.b.abs[:0] // == 1 (see Rat)
+			// z already in normal form
+		case x.exp < allBits:
+			z.a.abs = z.a.abs.set(x.mant)
+			t := z.b.abs.setUint64(1)
+			z.b.abs = t.shl(t, uint(allBits-x.exp))
+			z.norm()
+		}
+		return z, Exact
+
+	case zero:
+		return z.SetInt64(0), Exact
+
+	case inf:
+		return nil, makeAcc(x.neg)
+	}
+
+	panic("unreachable")
+}
+
+// Abs sets z to the (possibly rounded) value |x| (the absolute value of x)
+// and returns z.
+func (z *Float) Abs(x *Float) *Float {
+	z.Set(x)
+	z.neg = false
+	return z
+}
+
+// Neg sets z to the (possibly rounded) value of x with its sign negated,
+// and returns z.
+func (z *Float) Neg(x *Float) *Float {
+	z.Set(x)
+	z.neg = !z.neg
+	return z
+}
+
+func validateBinaryOperands(x, y *Float) {
+	if !debugFloat {
+		// avoid performance bugs
+		panic("validateBinaryOperands called but debugFloat is not set")
+	}
+	if len(x.mant) == 0 {
+		panic("empty mantissa for x")
+	}
+	if len(y.mant) == 0 {
+		panic("empty mantissa for y")
+	}
+}
+
+// z = x + y, ignoring signs of x and y for the addition
+// but using the sign of z for rounding the result.
+// x and y must have a non-empty mantissa and valid exponent.
+func (z *Float) uadd(x, y *Float) {
+	// Note: This implementation requires 2 shifts most of the
+	// time. It is also inefficient if exponents or precisions
+	// differ by wide margins. The following article describes
+	// an efficient (but much more complicated) implementation
+	// compatible with the internal representation used here:
+	//
+	// Vincent Lefèvre: "The Generic Multiple-Precision Floating-
+	// Point Addition With Exact Rounding (as in the MPFR Library)"
+	// http://www.vinc17.net/research/papers/rnc6.pdf
+
+	if debugFloat {
+		validateBinaryOperands(x, y)
+	}
+
+	// compute exponents ex, ey for mantissa with "binary point"
+	// on the right (mantissa.0) - use int64 to avoid overflow
+	ex := int64(x.exp) - int64(len(x.mant))*_W
+	ey := int64(y.exp) - int64(len(y.mant))*_W
+
+	al := alias(z.mant, x.mant) || alias(z.mant, y.mant)
+
+	// TODO(gri) having a combined add-and-shift primitive
+	//           could make this code significantly faster
+	switch {
+	case ex < ey:
+		if al {
+			t := nat(nil).shl(y.mant, uint(ey-ex))
+			z.mant = z.mant.add(x.mant, t)
+		} else {
+			z.mant = z.mant.shl(y.mant, uint(ey-ex))
+			z.mant = z.mant.add(x.mant, z.mant)
+		}
+	default:
+		// ex == ey, no shift needed
+		z.mant = z.mant.add(x.mant, y.mant)
+	case ex > ey:
+		if al {
+			t := nat(nil).shl(x.mant, uint(ex-ey))
+			z.mant = z.mant.add(t, y.mant)
+		} else {
+			z.mant = z.mant.shl(x.mant, uint(ex-ey))
+			z.mant = z.mant.add(z.mant, y.mant)
+		}
+		ex = ey
+	}
+	// len(z.mant) > 0
+
+	z.setExpAndRound(ex+int64(len(z.mant))*_W-fnorm(z.mant), 0)
+}
+
+// z = x - y for |x| > |y|, ignoring signs of x and y for the subtraction
+// but using the sign of z for rounding the result.
+// x and y must have a non-empty mantissa and valid exponent.
+func (z *Float) usub(x, y *Float) {
+	// This code is symmetric to uadd.
+	// We have not factored the common code out because
+	// eventually uadd (and usub) should be optimized
+	// by special-casing, and the code will diverge.
+
+	if debugFloat {
+		validateBinaryOperands(x, y)
+	}
+
+	ex := int64(x.exp) - int64(len(x.mant))*_W
+	ey := int64(y.exp) - int64(len(y.mant))*_W
+
+	al := alias(z.mant, x.mant) || alias(z.mant, y.mant)
+
+	switch {
+	case ex < ey:
+		if al {
+			t := nat(nil).shl(y.mant, uint(ey-ex))
+			z.mant = t.sub(x.mant, t)
+		} else {
+			z.mant = z.mant.shl(y.mant, uint(ey-ex))
+			z.mant = z.mant.sub(x.mant, z.mant)
+		}
+	default:
+		// ex == ey, no shift needed
+		z.mant = z.mant.sub(x.mant, y.mant)
+	case ex > ey:
+		if al {
+			t := nat(nil).shl(x.mant, uint(ex-ey))
+			z.mant = t.sub(t, y.mant)
+		} else {
+			z.mant = z.mant.shl(x.mant, uint(ex-ey))
+			z.mant = z.mant.sub(z.mant, y.mant)
+		}
+		ex = ey
+	}
+
+	// operands may have canceled each other out
+	if len(z.mant) == 0 {
+		z.acc = Exact
+		z.form = zero
+		z.neg = false
+		return
+	}
+	// len(z.mant) > 0
+
+	z.setExpAndRound(ex+int64(len(z.mant))*_W-fnorm(z.mant), 0)
+}
+
+// z = x * y, ignoring signs of x and y for the multiplication
+// but using the sign of z for rounding the result.
+// x and y must have a non-empty mantissa and valid exponent.
+func (z *Float) umul(x, y *Float) {
+	if debugFloat {
+		validateBinaryOperands(x, y)
+	}
+
+	// Note: This is doing too much work if the precision
+	// of z is less than the sum of the precisions of x
+	// and y which is often the case (e.g., if all floats
+	// have the same precision).
+	// TODO(gri) Optimize this for the common case.
+
+	e := int64(x.exp) + int64(y.exp)
+	if x == y {
+		z.mant = z.mant.sqr(x.mant)
+	} else {
+		z.mant = z.mant.mul(x.mant, y.mant)
+	}
+	z.setExpAndRound(e-fnorm(z.mant), 0)
+}
+
+// z = x / y, ignoring signs of x and y for the division
+// but using the sign of z for rounding the result.
+// x and y must have a non-empty mantissa and valid exponent.
+func (z *Float) uquo(x, y *Float) {
+	if debugFloat {
+		validateBinaryOperands(x, y)
+	}
+
+	// mantissa length in words for desired result precision + 1
+	// (at least one extra bit so we get the rounding bit after
+	// the division)
+	n := int(z.prec/_W) + 1
+
+	// compute adjusted x.mant such that we get enough result precision
+	xadj := x.mant
+	if d := n - len(x.mant) + len(y.mant); d > 0 {
+		// d extra words needed => add d "0 digits" to x
+		xadj = make(nat, len(x.mant)+d)
+		copy(xadj[d:], x.mant)
+	}
+	// TODO(gri): If we have too many digits (d < 0), we should be able
+	// to shorten x for faster division. But we must be extra careful
+	// with rounding in that case.
+
+	// Compute d before division since there may be aliasing of x.mant
+	// (via xadj) or y.mant with z.mant.
+	d := len(xadj) - len(y.mant)
+
+	// divide
+	var r nat
+	z.mant, r = z.mant.div(nil, xadj, y.mant)
+	e := int64(x.exp) - int64(y.exp) - int64(d-len(z.mant))*_W
+
+	// The result is long enough to include (at least) the rounding bit.
+	// If there's a non-zero remainder, the corresponding fractional part
+	// (if it were computed), would have a non-zero sticky bit (if it were
+	// zero, it couldn't have a non-zero remainder).
+	var sbit uint
+	if len(r) > 0 {
+		sbit = 1
+	}
+
+	z.setExpAndRound(e-fnorm(z.mant), sbit)
+}
+
+// ucmp returns -1, 0, or +1, depending on whether
+// |x| < |y|, |x| == |y|, or |x| > |y|.
+// x and y must have a non-empty mantissa and valid exponent.
+func (x *Float) ucmp(y *Float) int {
+	if debugFloat {
+		validateBinaryOperands(x, y)
+	}
+
+	switch {
+	case x.exp < y.exp:
+		return -1
+	case x.exp > y.exp:
+		return +1
+	}
+	// x.exp == y.exp
+
+	// compare mantissas
+	i := len(x.mant)
+	j := len(y.mant)
+	for i > 0 || j > 0 {
+		var xm, ym Word
+		if i > 0 {
+			i--
+			xm = x.mant[i]
+		}
+		if j > 0 {
+			j--
+			ym = y.mant[j]
+		}
+		switch {
+		case xm < ym:
+			return -1
+		case xm > ym:
+			return +1
+		}
+	}
+
+	return 0
+}
+
+// Handling of sign bit as defined by IEEE 754-2008, section 6.3:
+//
+// When neither the inputs nor result are NaN, the sign of a product or
+// quotient is the exclusive OR of the operands’ signs; the sign of a sum,
+// or of a difference x−y regarded as a sum x+(−y), differs from at most
+// one of the addends’ signs; and the sign of the result of conversions,
+// the quantize operation, the roundToIntegral operations, and the
+// roundToIntegralExact (see 5.3.1) is the sign of the first or only operand.
+// These rules shall apply even when operands or results are zero or infinite.
+//
+// When the sum of two operands with opposite signs (or the difference of
+// two operands with like signs) is exactly zero, the sign of that sum (or
+// difference) shall be +0 in all rounding-direction attributes except
+// roundTowardNegative; under that attribute, the sign of an exact zero
+// sum (or difference) shall be −0. However, x+x = x−(−x) retains the same
+// sign as x even when x is zero.
+//
+// See also: https://play.golang.org/p/RtH3UCt5IH
+
+// Add sets z to the rounded sum x+y and returns z. If z's precision is 0,
+// it is changed to the larger of x's or y's precision before the operation.
+// Rounding is performed according to z's precision and rounding mode; and
+// z's accuracy reports the result error relative to the exact (not rounded)
+// result. Add panics with ErrNaN if x and y are infinities with opposite
+// signs. The value of z is undefined in that case.
+func (z *Float) Add(x, y *Float) *Float {
+	if debugFloat {
+		x.validate()
+		y.validate()
+	}
+
+	if z.prec == 0 {
+		z.prec = umax32(x.prec, y.prec)
+	}
+
+	if x.form == finite && y.form == finite {
+		// x + y (common case)
+
+		// Below we set z.neg = x.neg, and when z aliases y this will
+		// change the y operand's sign. This is fine, because if an
+		// operand aliases the receiver it'll be overwritten, but we still
+		// want the original x.neg and y.neg values when we evaluate
+		// x.neg != y.neg, so we need to save y.neg before setting z.neg.
+		yneg := y.neg
+
+		z.neg = x.neg
+		if x.neg == yneg {
+			// x + y == x + y
+			// (-x) + (-y) == -(x + y)
+			z.uadd(x, y)
+		} else {
+			// x + (-y) == x - y == -(y - x)
+			// (-x) + y == y - x == -(x - y)
+			if x.ucmp(y) > 0 {
+				z.usub(x, y)
+			} else {
+				z.neg = !z.neg
+				z.usub(y, x)
+			}
+		}
+		if z.form == zero && z.mode == ToNegativeInf && z.acc == Exact {
+			z.neg = true
+		}
+		return z
+	}
+
+	if x.form == inf && y.form == inf && x.neg != y.neg {
+		// +Inf + -Inf
+		// -Inf + +Inf
+		// value of z is undefined but make sure it's valid
+		z.acc = Exact
+		z.form = zero
+		z.neg = false
+		panic(ErrNaN{"addition of infinities with opposite signs"})
+	}
+
+	if x.form == zero && y.form == zero {
+		// ±0 + ±0
+		z.acc = Exact
+		z.form = zero
+		z.neg = x.neg && y.neg // -0 + -0 == -0
+		return z
+	}
+
+	if x.form == inf || y.form == zero {
+		// ±Inf + y
+		// x + ±0
+		return z.Set(x)
+	}
+
+	// ±0 + y
+	// x + ±Inf
+	return z.Set(y)
+}
+
+// Sub sets z to the rounded difference x-y and returns z.
+// Precision, rounding, and accuracy reporting are as for Add.
+// Sub panics with ErrNaN if x and y are infinities with equal
+// signs. The value of z is undefined in that case.
+func (z *Float) Sub(x, y *Float) *Float {
+	if debugFloat {
+		x.validate()
+		y.validate()
+	}
+
+	if z.prec == 0 {
+		z.prec = umax32(x.prec, y.prec)
+	}
+
+	if x.form == finite && y.form == finite {
+		// x - y (common case)
+		yneg := y.neg
+		z.neg = x.neg
+		if x.neg != yneg {
+			// x - (-y) == x + y
+			// (-x) - y == -(x + y)
+			z.uadd(x, y)
+		} else {
+			// x - y == x - y == -(y - x)
+			// (-x) - (-y) == y - x == -(x - y)
+			if x.ucmp(y) > 0 {
+				z.usub(x, y)
+			} else {
+				z.neg = !z.neg
+				z.usub(y, x)
+			}
+		}
+		if z.form == zero && z.mode == ToNegativeInf && z.acc == Exact {
+			z.neg = true
+		}
+		return z
+	}
+
+	if x.form == inf && y.form == inf && x.neg == y.neg {
+		// +Inf - +Inf
+		// -Inf - -Inf
+		// value of z is undefined but make sure it's valid
+		z.acc = Exact
+		z.form = zero
+		z.neg = false
+		panic(ErrNaN{"subtraction of infinities with equal signs"})
+	}
+
+	if x.form == zero && y.form == zero {
+		// ±0 - ±0
+		z.acc = Exact
+		z.form = zero
+		z.neg = x.neg && !y.neg // -0 - +0 == -0
+		return z
+	}
+
+	if x.form == inf || y.form == zero {
+		// ±Inf - y
+		// x - ±0
+		return z.Set(x)
+	}
+
+	// ±0 - y
+	// x - ±Inf
+	return z.Neg(y)
+}
+
+// Mul sets z to the rounded product x*y and returns z.
+// Precision, rounding, and accuracy reporting are as for Add.
+// Mul panics with ErrNaN if one operand is zero and the other
+// operand an infinity. The value of z is undefined in that case.
+func (z *Float) Mul(x, y *Float) *Float {
+	if debugFloat {
+		x.validate()
+		y.validate()
+	}
+
+	if z.prec == 0 {
+		z.prec = umax32(x.prec, y.prec)
+	}
+
+	z.neg = x.neg != y.neg
+
+	if x.form == finite && y.form == finite {
+		// x * y (common case)
+		z.umul(x, y)
+		return z
+	}
+
+	z.acc = Exact
+	if x.form == zero && y.form == inf || x.form == inf && y.form == zero {
+		// ±0 * ±Inf
+		// ±Inf * ±0
+		// value of z is undefined but make sure it's valid
+		z.form = zero
+		z.neg = false
+		panic(ErrNaN{"multiplication of zero with infinity"})
+	}
+
+	if x.form == inf || y.form == inf {
+		// ±Inf * y
+		// x * ±Inf
+		z.form = inf
+		return z
+	}
+
+	// ±0 * y
+	// x * ±0
+	z.form = zero
+	return z
+}
+
+// Quo sets z to the rounded quotient x/y and returns z.
+// Precision, rounding, and accuracy reporting are as for Add.
+// Quo panics with ErrNaN if both operands are zero or infinities.
+// The value of z is undefined in that case.
+func (z *Float) Quo(x, y *Float) *Float {
+	if debugFloat {
+		x.validate()
+		y.validate()
+	}
+
+	if z.prec == 0 {
+		z.prec = umax32(x.prec, y.prec)
+	}
+
+	z.neg = x.neg != y.neg
+
+	if x.form == finite && y.form == finite {
+		// x / y (common case)
+		z.uquo(x, y)
+		return z
+	}
+
+	z.acc = Exact
+	if x.form == zero && y.form == zero || x.form == inf && y.form == inf {
+		// ±0 / ±0
+		// ±Inf / ±Inf
+		// value of z is undefined but make sure it's valid
+		z.form = zero
+		z.neg = false
+		panic(ErrNaN{"division of zero by zero or infinity by infinity"})
+	}
+
+	if x.form == zero || y.form == inf {
+		// ±0 / y
+		// x / ±Inf
+		z.form = zero
+		return z
+	}
+
+	// x / ±0
+	// ±Inf / y
+	z.form = inf
+	return z
+}
+
+// Cmp compares x and y and returns:
+//
+//	-1 if x <  y
+//	 0 if x == y (incl. -0 == 0, -Inf == -Inf, and +Inf == +Inf)
+//	+1 if x >  y
+func (x *Float) Cmp(y *Float) int {
+	if debugFloat {
+		x.validate()
+		y.validate()
+	}
+
+	mx := x.ord()
+	my := y.ord()
+	switch {
+	case mx < my:
+		return -1
+	case mx > my:
+		return +1
+	}
+	// mx == my
+
+	// only if |mx| == 1 we have to compare the mantissae
+	switch mx {
+	case -1:
+		return y.ucmp(x)
+	case +1:
+		return x.ucmp(y)
+	}
+
+	return 0
+}
+
+// ord classifies x and returns:
+//
+//	-2 if -Inf == x
+//	-1 if -Inf < x < 0
+//	 0 if x == 0 (signed or unsigned)
+//	+1 if 0 < x < +Inf
+//	+2 if x == +Inf
+func (x *Float) ord() int {
+	var m int
+	switch x.form {
+	case finite:
+		m = 1
+	case zero:
+		return 0
+	case inf:
+		m = 2
+	}
+	if x.neg {
+		m = -m
+	}
+	return m
+}
+
+func umax32(x, y uint32) uint32 {
+	if x > y {
+		return x
+	}
+	return y
+}
diff --git a/contrib/go/_std_1.19/src/math/big/floatconv.go b/contrib/go/_std_1.19/src/math/big/floatconv.go
new file mode 100644
index 0000000000..3bb51c7dea
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/big/floatconv.go
@@ -0,0 +1,302 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements string-to-Float conversion functions.
+
+package big
+
+import (
+	"fmt"
+	"io"
+	"strings"
+)
+
+var floatZero Float
+
+// SetString sets z to the value of s and returns z and a boolean indicating
+// success. s must be a floating-point number of the same format as accepted
+// by Parse, with base argument 0. The entire string (not just a prefix) must
+// be valid for success. If the operation failed, the value of z is undefined
+// but the returned value is nil.
+func (z *Float) SetString(s string) (*Float, bool) {
+	if f, _, err := z.Parse(s, 0); err == nil {
+		return f, true
+	}
+	return nil, false
+}
+
+// scan is like Parse but reads the longest possible prefix representing a valid
+// floating point number from an io.ByteScanner rather than a string. It serves
+// as the implementation of Parse. It does not recognize ±Inf and does not expect
+// EOF at the end.
+func (z *Float) scan(r io.ByteScanner, base int) (f *Float, b int, err error) {
+	prec := z.prec
+	if prec == 0 {
+		prec = 64
+	}
+
+	// A reasonable value in case of an error.
+	z.form = zero
+
+	// sign
+	z.neg, err = scanSign(r)
+	if err != nil {
+		return
+	}
+
+	// mantissa
+	var fcount int // fractional digit count; valid if <= 0
+	z.mant, b, fcount, err = z.mant.scan(r, base, true)
+	if err != nil {
+		return
+	}
+
+	// exponent
+	var exp int64
+	var ebase int
+	exp, ebase, err = scanExponent(r, true, base == 0)
+	if err != nil {
+		return
+	}
+
+	// special-case 0
+	if len(z.mant) == 0 {
+		z.prec = prec
+		z.acc = Exact
+		z.form = zero
+		f = z
+		return
+	}
+	// len(z.mant) > 0
+
+	// The mantissa may have a radix point (fcount <= 0) and there
+	// may be a nonzero exponent exp. The radix point amounts to a
+	// division by b**(-fcount). An exponent means multiplication by
+	// ebase**exp. Finally, mantissa normalization (shift left) requires
+	// a correcting multiplication by 2**(-shiftcount). Multiplications
+	// are commutative, so we can apply them in any order as long as there
+	// is no loss of precision. We only have powers of 2 and 10, and
+	// we split powers of 10 into the product of the same powers of
+	// 2 and 5. This reduces the size of the multiplication factor
+	// needed for base-10 exponents.
+
+	// normalize mantissa and determine initial exponent contributions
+	exp2 := int64(len(z.mant))*_W - fnorm(z.mant)
+	exp5 := int64(0)
+
+	// determine binary or decimal exponent contribution of radix point
+	if fcount < 0 {
+		// The mantissa has a radix point ddd.dddd; and
+		// -fcount is the number of digits to the right
+		// of '.'. Adjust relevant exponent accordingly.
+		d := int64(fcount)
+		switch b {
+		case 10:
+			exp5 = d
+			fallthrough // 10**e == 5**e * 2**e
+		case 2:
+			exp2 += d
+		case 8:
+			exp2 += d * 3 // octal digits are 3 bits each
+		case 16:
+			exp2 += d * 4 // hexadecimal digits are 4 bits each
+		default:
+			panic("unexpected mantissa base")
+		}
+		// fcount consumed - not needed anymore
+	}
+
+	// take actual exponent into account
+	switch ebase {
+	case 10:
+		exp5 += exp
+		fallthrough // see fallthrough above
+	case 2:
+		exp2 += exp
+	default:
+		panic("unexpected exponent base")
+	}
+	// exp consumed - not needed anymore
+
+	// apply 2**exp2
+	if MinExp <= exp2 && exp2 <= MaxExp {
+		z.prec = prec
+		z.form = finite
+		z.exp = int32(exp2)
+		f = z
+	} else {
+		err = fmt.Errorf("exponent overflow")
+		return
+	}
+
+	if exp5 == 0 {
+		// no decimal exponent contribution
+		z.round(0)
+		return
+	}
+	// exp5 != 0
+
+	// apply 5**exp5
+	p := new(Float).SetPrec(z.Prec() + 64) // use more bits for p -- TODO(gri) what is the right number?
+	if exp5 < 0 {
+		z.Quo(z, p.pow5(uint64(-exp5)))
+	} else {
+		z.Mul(z, p.pow5(uint64(exp5)))
+	}
+
+	return
+}
+
+// These powers of 5 fit into a uint64.
+//
+//	for p, q := uint64(0), uint64(1); p < q; p, q = q, q*5 {
+//		fmt.Println(q)
+//	}
+var pow5tab = [...]uint64{
+	1,
+	5,
+	25,
+	125,
+	625,
+	3125,
+	15625,
+	78125,
+	390625,
+	1953125,
+	9765625,
+	48828125,
+	244140625,
+	1220703125,
+	6103515625,
+	30517578125,
+	152587890625,
+	762939453125,
+	3814697265625,
+	19073486328125,
+	95367431640625,
+	476837158203125,
+	2384185791015625,
+	11920928955078125,
+	59604644775390625,
+	298023223876953125,
+	1490116119384765625,
+	7450580596923828125,
+}
+
+// pow5 sets z to 5**n and returns z.
+// n must not be negative.
+func (z *Float) pow5(n uint64) *Float {
+	const m = uint64(len(pow5tab) - 1)
+	if n <= m {
+		return z.SetUint64(pow5tab[n])
+	}
+	// n > m
+
+	z.SetUint64(pow5tab[m])
+	n -= m
+
+	// use more bits for f than for z
+	// TODO(gri) what is the right number?
+	f := new(Float).SetPrec(z.Prec() + 64).SetUint64(5)
+
+	for n > 0 {
+		if n&1 != 0 {
+			z.Mul(z, f)
+		}
+		f.Mul(f, f)
+		n >>= 1
+	}
+
+	return z
+}
+
+// Parse parses s which must contain a text representation of a floating-
+// point number with a mantissa in the given conversion base (the exponent
+// is always a decimal number), or a string representing an infinite value.
+//
+// For base 0, an underscore character “_” may appear between a base
+// prefix and an adjacent digit, and between successive digits; such
+// underscores do not change the value of the number, or the returned
+// digit count. Incorrect placement of underscores is reported as an
+// error if there are no other errors. If base != 0, underscores are
+// not recognized and thus terminate scanning like any other character
+// that is not a valid radix point or digit.
+//
+// It sets z to the (possibly rounded) value of the corresponding floating-
+// point value, and returns z, the actual base b, and an error err, if any.
+// The entire string (not just a prefix) must be consumed for success.
+// If z's precision is 0, it is changed to 64 before rounding takes effect.
+// The number must be of the form:
+//
+//	number    = [ sign ] ( float | "inf" | "Inf" ) .
+//	sign      = "+" | "-" .
+//	float     = ( mantissa | prefix pmantissa ) [ exponent ] .
+//	prefix    = "0" [ "b" | "B" | "o" | "O" | "x" | "X" ] .
+//	mantissa  = digits "." [ digits ] | digits | "." digits .
+//	pmantissa = [ "_" ] digits "." [ digits ] | [ "_" ] digits | "." digits .
+//	exponent  = ( "e" | "E" | "p" | "P" ) [ sign ] digits .
+//	digits    = digit { [ "_" ] digit } .
+//	digit     = "0" ... "9" | "a" ... "z" | "A" ... "Z" .
+//
+// The base argument must be 0, 2, 8, 10, or 16. Providing an invalid base
+// argument will lead to a run-time panic.
+//
+// For base 0, the number prefix determines the actual base: A prefix of
+// “0b” or “0B” selects base 2, “0o” or “0O” selects base 8, and
+// “0x” or “0X” selects base 16. Otherwise, the actual base is 10 and
+// no prefix is accepted. The octal prefix "0" is not supported (a leading
+// "0" is simply considered a "0").
+//
+// A "p" or "P" exponent indicates a base 2 (rather then base 10) exponent;
+// for instance, "0x1.fffffffffffffp1023" (using base 0) represents the
+// maximum float64 value. For hexadecimal mantissae, the exponent character
+// must be one of 'p' or 'P', if present (an "e" or "E" exponent indicator
+// cannot be distinguished from a mantissa digit).
+//
+// The returned *Float f is nil and the value of z is valid but not
+// defined if an error is reported.
+func (z *Float) Parse(s string, base int) (f *Float, b int, err error) {
+	// scan doesn't handle ±Inf
+	if len(s) == 3 && (s == "Inf" || s == "inf") {
+		f = z.SetInf(false)
+		return
+	}
+	if len(s) == 4 && (s[0] == '+' || s[0] == '-') && (s[1:] == "Inf" || s[1:] == "inf") {
+		f = z.SetInf(s[0] == '-')
+		return
+	}
+
+	r := strings.NewReader(s)
+	if f, b, err = z.scan(r, base); err != nil {
+		return
+	}
+
+	// entire string must have been consumed
+	if ch, err2 := r.ReadByte(); err2 == nil {
+		err = fmt.Errorf("expected end of string, found %q", ch)
+	} else if err2 != io.EOF {
+		err = err2
+	}
+
+	return
+}
+
+// ParseFloat is like f.Parse(s, base) with f set to the given precision
+// and rounding mode.
+func ParseFloat(s string, base int, prec uint, mode RoundingMode) (f *Float, b int, err error) {
+	return new(Float).SetPrec(prec).SetMode(mode).Parse(s, base)
+}
+
+var _ fmt.Scanner = (*Float)(nil) // *Float must implement fmt.Scanner
+
+// Scan is a support routine for fmt.Scanner; it sets z to the value of
+// the scanned number. It accepts formats whose verbs are supported by
+// fmt.Scan for floating point values, which are:
+// 'b' (binary), 'e', 'E', 'f', 'F', 'g' and 'G'.
+// Scan doesn't handle ±Inf.
+func (z *Float) Scan(s fmt.ScanState, ch rune) error {
+	s.SkipSpace()
+	_, _, err := z.scan(byteReader{s}, 0)
+	return err
+}
diff --git a/contrib/go/_std_1.19/src/math/big/floatmarsh.go b/contrib/go/_std_1.19/src/math/big/floatmarsh.go
new file mode 100644
index 0000000000..990e085abe
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/big/floatmarsh.go
@@ -0,0 +1,127 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements encoding/decoding of Floats.
+
+package big
+
+import (
+	"encoding/binary"
+	"errors"
+	"fmt"
+)
+
+// Gob codec version. Permits backward-compatible changes to the encoding.
+const floatGobVersion byte = 1
+
+// GobEncode implements the gob.GobEncoder interface.
+// The Float value and all its attributes (precision,
+// rounding mode, accuracy) are marshaled.
+func (x *Float) GobEncode() ([]byte, error) {
+	if x == nil {
+		return nil, nil
+	}
+
+	// determine max. space (bytes) required for encoding
+	sz := 1 + 1 + 4 // version + mode|acc|form|neg (3+2+2+1bit) + prec
+	n := 0          // number of mantissa words
+	if x.form == finite {
+		// add space for mantissa and exponent
+		n = int((x.prec + (_W - 1)) / _W) // required mantissa length in words for given precision
+		// actual mantissa slice could be shorter (trailing 0's) or longer (unused bits):
+		// - if shorter, only encode the words present
+		// - if longer, cut off unused words when encoding in bytes
+		//   (in practice, this should never happen since rounding
+		//   takes care of it, but be safe and do it always)
+		if len(x.mant) < n {
+			n = len(x.mant)
+		}
+		// len(x.mant) >= n
+		sz += 4 + n*_S // exp + mant
+	}
+	buf := make([]byte, sz)
+
+	buf[0] = floatGobVersion
+	b := byte(x.mode&7)<<5 | byte((x.acc+1)&3)<<3 | byte(x.form&3)<<1
+	if x.neg {
+		b |= 1
+	}
+	buf[1] = b
+	binary.BigEndian.PutUint32(buf[2:], x.prec)
+
+	if x.form == finite {
+		binary.BigEndian.PutUint32(buf[6:], uint32(x.exp))
+		x.mant[len(x.mant)-n:].bytes(buf[10:]) // cut off unused trailing words
+	}
+
+	return buf, nil
+}
+
+// GobDecode implements the gob.GobDecoder interface.
+// The result is rounded per the precision and rounding mode of
+// z unless z's precision is 0, in which case z is set exactly
+// to the decoded value.
+func (z *Float) GobDecode(buf []byte) error {
+	if len(buf) == 0 {
+		// Other side sent a nil or default value.
+		*z = Float{}
+		return nil
+	}
+	if len(buf) < 6 {
+		return errors.New("Float.GobDecode: buffer too small")
+	}
+
+	if buf[0] != floatGobVersion {
+		return fmt.Errorf("Float.GobDecode: encoding version %d not supported", buf[0])
+	}
+
+	oldPrec := z.prec
+	oldMode := z.mode
+
+	b := buf[1]
+	z.mode = RoundingMode((b >> 5) & 7)
+	z.acc = Accuracy((b>>3)&3) - 1
+	z.form = form((b >> 1) & 3)
+	z.neg = b&1 != 0
+	z.prec = binary.BigEndian.Uint32(buf[2:])
+
+	if z.form == finite {
+		if len(buf) < 10 {
+			return errors.New("Float.GobDecode: buffer too small for finite form float")
+		}
+		z.exp = int32(binary.BigEndian.Uint32(buf[6:]))
+		z.mant = z.mant.setBytes(buf[10:])
+	}
+
+	if oldPrec != 0 {
+		z.mode = oldMode
+		z.SetPrec(uint(oldPrec))
+	}
+
+	return nil
+}
+
+// MarshalText implements the encoding.TextMarshaler interface.
+// Only the Float value is marshaled (in full precision), other
+// attributes such as precision or accuracy are ignored.
+func (x *Float) MarshalText() (text []byte, err error) {
+	if x == nil {
+		return []byte("<nil>"), nil
+	}
+	var buf []byte
+	return x.Append(buf, 'g', -1), nil
+}
+
+// UnmarshalText implements the encoding.TextUnmarshaler interface.
+// The result is rounded per the precision and rounding mode of z.
+// If z's precision is 0, it is changed to 64 before rounding takes
+// effect.
+func (z *Float) UnmarshalText(text []byte) error {
+	// TODO(gri): get rid of the []byte/string conversion
+	_, _, err := z.Parse(string(text), 0)
+	if err != nil {
+		err = fmt.Errorf("math/big: cannot unmarshal %q into a *big.Float (%v)", text, err)
+	}
+	return err
+}
diff --git a/contrib/go/_std_1.18/src/math/big/ftoa.go b/contrib/go/_std_1.19/src/math/big/ftoa.go
index 5506e6e425..5506e6e425 100644
--- a/contrib/go/_std_1.18/src/math/big/ftoa.go
+++ b/contrib/go/_std_1.19/src/math/big/ftoa.go
diff --git a/contrib/go/_std_1.19/src/math/big/int.go b/contrib/go/_std_1.19/src/math/big/int.go
new file mode 100644
index 0000000000..ec168f8ffe
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/big/int.go
@@ -0,0 +1,1225 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements signed multi-precision integers.
+
+package big
+
+import (
+	"fmt"
+	"io"
+	"math/rand"
+	"strings"
+)
+
+// An Int represents a signed multi-precision integer.
+// The zero value for an Int represents the value 0.
+//
+// Operations always take pointer arguments (*Int) rather
+// than Int values, and each unique Int value requires
+// its own unique *Int pointer. To "copy" an Int value,
+// an existing (or newly allocated) Int must be set to
+// a new value using the Int.Set method; shallow copies
+// of Ints are not supported and may lead to errors.
+type Int struct {
+	neg bool // sign
+	abs nat  // absolute value of the integer
+}
+
+var intOne = &Int{false, natOne}
+
+// Sign returns:
+//
+//	-1 if x <  0
+//	 0 if x == 0
+//	+1 if x >  0
+func (x *Int) Sign() int {
+	if len(x.abs) == 0 {
+		return 0
+	}
+	if x.neg {
+		return -1
+	}
+	return 1
+}
+
+// SetInt64 sets z to x and returns z.
+func (z *Int) SetInt64(x int64) *Int {
+	neg := false
+	if x < 0 {
+		neg = true
+		x = -x
+	}
+	z.abs = z.abs.setUint64(uint64(x))
+	z.neg = neg
+	return z
+}
+
+// SetUint64 sets z to x and returns z.
+func (z *Int) SetUint64(x uint64) *Int {
+	z.abs = z.abs.setUint64(x)
+	z.neg = false
+	return z
+}
+
+// NewInt allocates and returns a new Int set to x.
+func NewInt(x int64) *Int {
+	return new(Int).SetInt64(x)
+}
+
+// Set sets z to x and returns z.
+func (z *Int) Set(x *Int) *Int {
+	if z != x {
+		z.abs = z.abs.set(x.abs)
+		z.neg = x.neg
+	}
+	return z
+}
+
+// Bits provides raw (unchecked but fast) access to x by returning its
+// absolute value as a little-endian Word slice. The result and x share
+// the same underlying array.
+// Bits is intended to support implementation of missing low-level Int
+// functionality outside this package; it should be avoided otherwise.
+func (x *Int) Bits() []Word {
+	return x.abs
+}
+
+// SetBits provides raw (unchecked but fast) access to z by setting its
+// value to abs, interpreted as a little-endian Word slice, and returning
+// z. The result and abs share the same underlying array.
+// SetBits is intended to support implementation of missing low-level Int
+// functionality outside this package; it should be avoided otherwise.
+func (z *Int) SetBits(abs []Word) *Int {
+	z.abs = nat(abs).norm()
+	z.neg = false
+	return z
+}
+
+// Abs sets z to |x| (the absolute value of x) and returns z.
+func (z *Int) Abs(x *Int) *Int {
+	z.Set(x)
+	z.neg = false
+	return z
+}
+
+// Neg sets z to -x and returns z.
+func (z *Int) Neg(x *Int) *Int {
+	z.Set(x)
+	z.neg = len(z.abs) > 0 && !z.neg // 0 has no sign
+	return z
+}
+
+// Add sets z to the sum x+y and returns z.
+func (z *Int) Add(x, y *Int) *Int {
+	neg := x.neg
+	if x.neg == y.neg {
+		// x + y == x + y
+		// (-x) + (-y) == -(x + y)
+		z.abs = z.abs.add(x.abs, y.abs)
+	} else {
+		// x + (-y) == x - y == -(y - x)
+		// (-x) + y == y - x == -(x - y)
+		if x.abs.cmp(y.abs) >= 0 {
+			z.abs = z.abs.sub(x.abs, y.abs)
+		} else {
+			neg = !neg
+			z.abs = z.abs.sub(y.abs, x.abs)
+		}
+	}
+	z.neg = len(z.abs) > 0 && neg // 0 has no sign
+	return z
+}
+
+// Sub sets z to the difference x-y and returns z.
+func (z *Int) Sub(x, y *Int) *Int {
+	neg := x.neg
+	if x.neg != y.neg {
+		// x - (-y) == x + y
+		// (-x) - y == -(x + y)
+		z.abs = z.abs.add(x.abs, y.abs)
+	} else {
+		// x - y == x - y == -(y - x)
+		// (-x) - (-y) == y - x == -(x - y)
+		if x.abs.cmp(y.abs) >= 0 {
+			z.abs = z.abs.sub(x.abs, y.abs)
+		} else {
+			neg = !neg
+			z.abs = z.abs.sub(y.abs, x.abs)
+		}
+	}
+	z.neg = len(z.abs) > 0 && neg // 0 has no sign
+	return z
+}
+
+// Mul sets z to the product x*y and returns z.
+func (z *Int) Mul(x, y *Int) *Int {
+	// x * y == x * y
+	// x * (-y) == -(x * y)
+	// (-x) * y == -(x * y)
+	// (-x) * (-y) == x * y
+	if x == y {
+		z.abs = z.abs.sqr(x.abs)
+		z.neg = false
+		return z
+	}
+	z.abs = z.abs.mul(x.abs, y.abs)
+	z.neg = len(z.abs) > 0 && x.neg != y.neg // 0 has no sign
+	return z
+}
+
+// MulRange sets z to the product of all integers
+// in the range [a, b] inclusively and returns z.
+// If a > b (empty range), the result is 1.
+func (z *Int) MulRange(a, b int64) *Int {
+	switch {
+	case a > b:
+		return z.SetInt64(1) // empty range
+	case a <= 0 && b >= 0:
+		return z.SetInt64(0) // range includes 0
+	}
+	// a <= b && (b < 0 || a > 0)
+
+	neg := false
+	if a < 0 {
+		neg = (b-a)&1 == 0
+		a, b = -b, -a
+	}
+
+	z.abs = z.abs.mulRange(uint64(a), uint64(b))
+	z.neg = neg
+	return z
+}
+
+// Binomial sets z to the binomial coefficient of (n, k) and returns z.
+func (z *Int) Binomial(n, k int64) *Int {
+	// reduce the number of multiplications by reducing k
+	if n/2 < k && k <= n {
+		k = n - k // Binomial(n, k) == Binomial(n, n-k)
+	}
+	var a, b Int
+	a.MulRange(n-k+1, n)
+	b.MulRange(1, k)
+	return z.Quo(&a, &b)
+}
+
+// Quo sets z to the quotient x/y for y != 0 and returns z.
+// If y == 0, a division-by-zero run-time panic occurs.
+// Quo implements truncated division (like Go); see QuoRem for more details.
+func (z *Int) Quo(x, y *Int) *Int {
+	z.abs, _ = z.abs.div(nil, x.abs, y.abs)
+	z.neg = len(z.abs) > 0 && x.neg != y.neg // 0 has no sign
+	return z
+}
+
+// Rem sets z to the remainder x%y for y != 0 and returns z.
+// If y == 0, a division-by-zero run-time panic occurs.
+// Rem implements truncated modulus (like Go); see QuoRem for more details.
+func (z *Int) Rem(x, y *Int) *Int {
+	_, z.abs = nat(nil).div(z.abs, x.abs, y.abs)
+	z.neg = len(z.abs) > 0 && x.neg // 0 has no sign
+	return z
+}
+
+// QuoRem sets z to the quotient x/y and r to the remainder x%y
+// and returns the pair (z, r) for y != 0.
+// If y == 0, a division-by-zero run-time panic occurs.
+//
+// QuoRem implements T-division and modulus (like Go):
+//
+//	q = x/y      with the result truncated to zero
+//	r = x - y*q
+//
+// (See Daan Leijen, “Division and Modulus for Computer Scientists”.)
+// See DivMod for Euclidean division and modulus (unlike Go).
+func (z *Int) QuoRem(x, y, r *Int) (*Int, *Int) {
+	z.abs, r.abs = z.abs.div(r.abs, x.abs, y.abs)
+	z.neg, r.neg = len(z.abs) > 0 && x.neg != y.neg, len(r.abs) > 0 && x.neg // 0 has no sign
+	return z, r
+}
+
+// Div sets z to the quotient x/y for y != 0 and returns z.
+// If y == 0, a division-by-zero run-time panic occurs.
+// Div implements Euclidean division (unlike Go); see DivMod for more details.
+func (z *Int) Div(x, y *Int) *Int {
+	y_neg := y.neg // z may be an alias for y
+	var r Int
+	z.QuoRem(x, y, &r)
+	if r.neg {
+		if y_neg {
+			z.Add(z, intOne)
+		} else {
+			z.Sub(z, intOne)
+		}
+	}
+	return z
+}
+
+// Mod sets z to the modulus x%y for y != 0 and returns z.
+// If y == 0, a division-by-zero run-time panic occurs.
+// Mod implements Euclidean modulus (unlike Go); see DivMod for more details.
+func (z *Int) Mod(x, y *Int) *Int {
+	y0 := y // save y
+	if z == y || alias(z.abs, y.abs) {
+		y0 = new(Int).Set(y)
+	}
+	var q Int
+	q.QuoRem(x, y, z)
+	if z.neg {
+		if y0.neg {
+			z.Sub(z, y0)
+		} else {
+			z.Add(z, y0)
+		}
+	}
+	return z
+}
+
+// DivMod sets z to the quotient x div y and m to the modulus x mod y
+// and returns the pair (z, m) for y != 0.
+// If y == 0, a division-by-zero run-time panic occurs.
+//
+// DivMod implements Euclidean division and modulus (unlike Go):
+//
+//	q = x div y  such that
+//	m = x - y*q  with 0 <= m < |y|
+//
+// (See Raymond T. Boute, “The Euclidean definition of the functions
+// div and mod”. ACM Transactions on Programming Languages and
+// Systems (TOPLAS), 14(2):127-144, New York, NY, USA, 4/1992.
+// ACM press.)
+// See QuoRem for T-division and modulus (like Go).
+func (z *Int) DivMod(x, y, m *Int) (*Int, *Int) {
+	y0 := y // save y
+	if z == y || alias(z.abs, y.abs) {
+		y0 = new(Int).Set(y)
+	}
+	z.QuoRem(x, y, m)
+	if m.neg {
+		if y0.neg {
+			z.Add(z, intOne)
+			m.Sub(m, y0)
+		} else {
+			z.Sub(z, intOne)
+			m.Add(m, y0)
+		}
+	}
+	return z, m
+}
+
+// Cmp compares x and y and returns:
+//
+//	-1 if x <  y
+//	 0 if x == y
+//	+1 if x >  y
+func (x *Int) Cmp(y *Int) (r int) {
+	// x cmp y == x cmp y
+	// x cmp (-y) == x
+	// (-x) cmp y == y
+	// (-x) cmp (-y) == -(x cmp y)
+	switch {
+	case x == y:
+		// nothing to do
+	case x.neg == y.neg:
+		r = x.abs.cmp(y.abs)
+		if x.neg {
+			r = -r
+		}
+	case x.neg:
+		r = -1
+	default:
+		r = 1
+	}
+	return
+}
+
+// CmpAbs compares the absolute values of x and y and returns:
+//
+//	-1 if |x| <  |y|
+//	 0 if |x| == |y|
+//	+1 if |x| >  |y|
+func (x *Int) CmpAbs(y *Int) int {
+	return x.abs.cmp(y.abs)
+}
+
+// low32 returns the least significant 32 bits of x.
+func low32(x nat) uint32 {
+	if len(x) == 0 {
+		return 0
+	}
+	return uint32(x[0])
+}
+
+// low64 returns the least significant 64 bits of x.
+func low64(x nat) uint64 {
+	if len(x) == 0 {
+		return 0
+	}
+	v := uint64(x[0])
+	if _W == 32 && len(x) > 1 {
+		return uint64(x[1])<<32 | v
+	}
+	return v
+}
+
+// Int64 returns the int64 representation of x.
+// If x cannot be represented in an int64, the result is undefined.
+func (x *Int) Int64() int64 {
+	v := int64(low64(x.abs))
+	if x.neg {
+		v = -v
+	}
+	return v
+}
+
+// Uint64 returns the uint64 representation of x.
+// If x cannot be represented in a uint64, the result is undefined.
+func (x *Int) Uint64() uint64 {
+	return low64(x.abs)
+}
+
+// IsInt64 reports whether x can be represented as an int64.
+func (x *Int) IsInt64() bool {
+	if len(x.abs) <= 64/_W {
+		w := int64(low64(x.abs))
+		return w >= 0 || x.neg && w == -w
+	}
+	return false
+}
+
+// IsUint64 reports whether x can be represented as a uint64.
+func (x *Int) IsUint64() bool {
+	return !x.neg && len(x.abs) <= 64/_W
+}
+
+// SetString sets z to the value of s, interpreted in the given base,
+// and returns z and a boolean indicating success. The entire string
+// (not just a prefix) must be valid for success. If SetString fails,
+// the value of z is undefined but the returned value is nil.
+//
+// The base argument must be 0 or a value between 2 and MaxBase.
+// For base 0, the number prefix determines the actual base: A prefix of
+// “0b” or “0B” selects base 2, “0”, “0o” or “0O” selects base 8,
+// and “0x” or “0X” selects base 16. Otherwise, the selected base is 10
+// and no prefix is accepted.
+//
+// For bases <= 36, lower and upper case letters are considered the same:
+// The letters 'a' to 'z' and 'A' to 'Z' represent digit values 10 to 35.
+// For bases > 36, the upper case letters 'A' to 'Z' represent the digit
+// values 36 to 61.
+//
+// For base 0, an underscore character “_” may appear between a base
+// prefix and an adjacent digit, and between successive digits; such
+// underscores do not change the value of the number.
+// Incorrect placement of underscores is reported as an error if there
+// are no other errors. If base != 0, underscores are not recognized
+// and act like any other character that is not a valid digit.
+func (z *Int) SetString(s string, base int) (*Int, bool) {
+	return z.setFromScanner(strings.NewReader(s), base)
+}
+
+// setFromScanner implements SetString given an io.ByteScanner.
+// For documentation see comments of SetString.
+func (z *Int) setFromScanner(r io.ByteScanner, base int) (*Int, bool) {
+	if _, _, err := z.scan(r, base); err != nil {
+		return nil, false
+	}
+	// entire content must have been consumed
+	if _, err := r.ReadByte(); err != io.EOF {
+		return nil, false
+	}
+	return z, true // err == io.EOF => scan consumed all content of r
+}
+
+// SetBytes interprets buf as the bytes of a big-endian unsigned
+// integer, sets z to that value, and returns z.
+func (z *Int) SetBytes(buf []byte) *Int {
+	z.abs = z.abs.setBytes(buf)
+	z.neg = false
+	return z
+}
+
+// Bytes returns the absolute value of x as a big-endian byte slice.
+//
+// To use a fixed length slice, or a preallocated one, use FillBytes.
+func (x *Int) Bytes() []byte {
+	buf := make([]byte, len(x.abs)*_S)
+	return buf[x.abs.bytes(buf):]
+}
+
+// FillBytes sets buf to the absolute value of x, storing it as a zero-extended
+// big-endian byte slice, and returns buf.
+//
+// If the absolute value of x doesn't fit in buf, FillBytes will panic.
+func (x *Int) FillBytes(buf []byte) []byte {
+	// Clear whole buffer. (This gets optimized into a memclr.)
+	for i := range buf {
+		buf[i] = 0
+	}
+	x.abs.bytes(buf)
+	return buf
+}
+
+// BitLen returns the length of the absolute value of x in bits.
+// The bit length of 0 is 0.
+func (x *Int) BitLen() int {
+	return x.abs.bitLen()
+}
+
+// TrailingZeroBits returns the number of consecutive least significant zero
+// bits of |x|.
+func (x *Int) TrailingZeroBits() uint {
+	return x.abs.trailingZeroBits()
+}
+
+// Exp sets z = x**y mod |m| (i.e. the sign of m is ignored), and returns z.
+// If m == nil or m == 0, z = x**y unless y <= 0 then z = 1. If m != 0, y < 0,
+// and x and m are not relatively prime, z is unchanged and nil is returned.
+//
+// Modular exponentiation of inputs of a particular size is not a
+// cryptographically constant-time operation.
+func (z *Int) Exp(x, y, m *Int) *Int {
+	// See Knuth, volume 2, section 4.6.3.
+	xWords := x.abs
+	if y.neg {
+		if m == nil || len(m.abs) == 0 {
+			return z.SetInt64(1)
+		}
+		// for y < 0: x**y mod m == (x**(-1))**|y| mod m
+		inverse := new(Int).ModInverse(x, m)
+		if inverse == nil {
+			return nil
+		}
+		xWords = inverse.abs
+	}
+	yWords := y.abs
+
+	var mWords nat
+	if m != nil {
+		if z == m || alias(z.abs, m.abs) {
+			m = new(Int).Set(m)
+		}
+		mWords = m.abs // m.abs may be nil for m == 0
+	}
+
+	z.abs = z.abs.expNN(xWords, yWords, mWords)
+	z.neg = len(z.abs) > 0 && x.neg && len(yWords) > 0 && yWords[0]&1 == 1 // 0 has no sign
+	if z.neg && len(mWords) > 0 {
+		// make modulus result positive
+		z.abs = z.abs.sub(mWords, z.abs) // z == x**y mod |m| && 0 <= z < |m|
+		z.neg = false
+	}
+
+	return z
+}
+
+// GCD sets z to the greatest common divisor of a and b and returns z.
+// If x or y are not nil, GCD sets their value such that z = a*x + b*y.
+//
+// a and b may be positive, zero or negative. (Before Go 1.14 both had
+// to be > 0.) Regardless of the signs of a and b, z is always >= 0.
+//
+// If a == b == 0, GCD sets z = x = y = 0.
+//
+// If a == 0 and b != 0, GCD sets z = |b|, x = 0, y = sign(b) * 1.
+//
+// If a != 0 and b == 0, GCD sets z = |a|, x = sign(a) * 1, y = 0.
+func (z *Int) GCD(x, y, a, b *Int) *Int {
+	if len(a.abs) == 0 || len(b.abs) == 0 {
+		lenA, lenB, negA, negB := len(a.abs), len(b.abs), a.neg, b.neg
+		if lenA == 0 {
+			z.Set(b)
+		} else {
+			z.Set(a)
+		}
+		z.neg = false
+		if x != nil {
+			if lenA == 0 {
+				x.SetUint64(0)
+			} else {
+				x.SetUint64(1)
+				x.neg = negA
+			}
+		}
+		if y != nil {
+			if lenB == 0 {
+				y.SetUint64(0)
+			} else {
+				y.SetUint64(1)
+				y.neg = negB
+			}
+		}
+		return z
+	}
+
+	return z.lehmerGCD(x, y, a, b)
+}
+
+// lehmerSimulate attempts to simulate several Euclidean update steps
+// using the leading digits of A and B.  It returns u0, u1, v0, v1
+// such that A and B can be updated as:
+//
+//	A = u0*A + v0*B
+//	B = u1*A + v1*B
+//
+// Requirements: A >= B and len(B.abs) >= 2
+// Since we are calculating with full words to avoid overflow,
+// we use 'even' to track the sign of the cosequences.
+// For even iterations: u0, v1 >= 0 && u1, v0 <= 0
+// For odd  iterations: u0, v1 <= 0 && u1, v0 >= 0
+func lehmerSimulate(A, B *Int) (u0, u1, v0, v1 Word, even bool) {
+	// initialize the digits
+	var a1, a2, u2, v2 Word
+
+	m := len(B.abs) // m >= 2
+	n := len(A.abs) // n >= m >= 2
+
+	// extract the top Word of bits from A and B
+	h := nlz(A.abs[n-1])
+	a1 = A.abs[n-1]<<h | A.abs[n-2]>>(_W-h)
+	// B may have implicit zero words in the high bits if the lengths differ
+	switch {
+	case n == m:
+		a2 = B.abs[n-1]<<h | B.abs[n-2]>>(_W-h)
+	case n == m+1:
+		a2 = B.abs[n-2] >> (_W - h)
+	default:
+		a2 = 0
+	}
+
+	// Since we are calculating with full words to avoid overflow,
+	// we use 'even' to track the sign of the cosequences.
+	// For even iterations: u0, v1 >= 0 && u1, v0 <= 0
+	// For odd  iterations: u0, v1 <= 0 && u1, v0 >= 0
+	// The first iteration starts with k=1 (odd).
+	even = false
+	// variables to track the cosequences
+	u0, u1, u2 = 0, 1, 0
+	v0, v1, v2 = 0, 0, 1
+
+	// Calculate the quotient and cosequences using Collins' stopping condition.
+	// Note that overflow of a Word is not possible when computing the remainder
+	// sequence and cosequences since the cosequence size is bounded by the input size.
+	// See section 4.2 of Jebelean for details.
+	for a2 >= v2 && a1-a2 >= v1+v2 {
+		q, r := a1/a2, a1%a2
+		a1, a2 = a2, r
+		u0, u1, u2 = u1, u2, u1+q*u2
+		v0, v1, v2 = v1, v2, v1+q*v2
+		even = !even
+	}
+	return
+}
+
+// lehmerUpdate updates the inputs A and B such that:
+//
+//	A = u0*A + v0*B
+//	B = u1*A + v1*B
+//
+// where the signs of u0, u1, v0, v1 are given by even
+// For even == true: u0, v1 >= 0 && u1, v0 <= 0
+// For even == false: u0, v1 <= 0 && u1, v0 >= 0
+// q, r, s, t are temporary variables to avoid allocations in the multiplication
+func lehmerUpdate(A, B, q, r, s, t *Int, u0, u1, v0, v1 Word, even bool) {
+
+	t.abs = t.abs.setWord(u0)
+	s.abs = s.abs.setWord(v0)
+	t.neg = !even
+	s.neg = even
+
+	t.Mul(A, t)
+	s.Mul(B, s)
+
+	r.abs = r.abs.setWord(u1)
+	q.abs = q.abs.setWord(v1)
+	r.neg = even
+	q.neg = !even
+
+	r.Mul(A, r)
+	q.Mul(B, q)
+
+	A.Add(t, s)
+	B.Add(r, q)
+}
+
+// euclidUpdate performs a single step of the Euclidean GCD algorithm
+// if extended is true, it also updates the cosequence Ua, Ub
+func euclidUpdate(A, B, Ua, Ub, q, r, s, t *Int, extended bool) {
+	q, r = q.QuoRem(A, B, r)
+
+	*A, *B, *r = *B, *r, *A
+
+	if extended {
+		// Ua, Ub = Ub, Ua - q*Ub
+		t.Set(Ub)
+		s.Mul(Ub, q)
+		Ub.Sub(Ua, s)
+		Ua.Set(t)
+	}
+}
+
+// lehmerGCD sets z to the greatest common divisor of a and b,
+// which both must be != 0, and returns z.
+// If x or y are not nil, their values are set such that z = a*x + b*y.
+// See Knuth, The Art of Computer Programming, Vol. 2, Section 4.5.2, Algorithm L.
+// This implementation uses the improved condition by Collins requiring only one
+// quotient and avoiding the possibility of single Word overflow.
+// See Jebelean, "Improving the multiprecision Euclidean algorithm",
+// Design and Implementation of Symbolic Computation Systems, pp 45-58.
+// The cosequences are updated according to Algorithm 10.45 from
+// Cohen et al. "Handbook of Elliptic and Hyperelliptic Curve Cryptography" pp 192.
+func (z *Int) lehmerGCD(x, y, a, b *Int) *Int {
+	var A, B, Ua, Ub *Int
+
+	A = new(Int).Abs(a)
+	B = new(Int).Abs(b)
+
+	extended := x != nil || y != nil
+
+	if extended {
+		// Ua (Ub) tracks how many times input a has been accumulated into A (B).
+		Ua = new(Int).SetInt64(1)
+		Ub = new(Int)
+	}
+
+	// temp variables for multiprecision update
+	q := new(Int)
+	r := new(Int)
+	s := new(Int)
+	t := new(Int)
+
+	// ensure A >= B
+	if A.abs.cmp(B.abs) < 0 {
+		A, B = B, A
+		Ub, Ua = Ua, Ub
+	}
+
+	// loop invariant A >= B
+	for len(B.abs) > 1 {
+		// Attempt to calculate in single-precision using leading words of A and B.
+		u0, u1, v0, v1, even := lehmerSimulate(A, B)
+
+		// multiprecision Step
+		if v0 != 0 {
+			// Simulate the effect of the single-precision steps using the cosequences.
+			// A = u0*A + v0*B
+			// B = u1*A + v1*B
+			lehmerUpdate(A, B, q, r, s, t, u0, u1, v0, v1, even)
+
+			if extended {
+				// Ua = u0*Ua + v0*Ub
+				// Ub = u1*Ua + v1*Ub
+				lehmerUpdate(Ua, Ub, q, r, s, t, u0, u1, v0, v1, even)
+			}
+
+		} else {
+			// Single-digit calculations failed to simulate any quotients.
+			// Do a standard Euclidean step.
+			euclidUpdate(A, B, Ua, Ub, q, r, s, t, extended)
+		}
+	}
+
+	if len(B.abs) > 0 {
+		// extended Euclidean algorithm base case if B is a single Word
+		if len(A.abs) > 1 {
+			// A is longer than a single Word, so one update is needed.
+			euclidUpdate(A, B, Ua, Ub, q, r, s, t, extended)
+		}
+		if len(B.abs) > 0 {
+			// A and B are both a single Word.
+			aWord, bWord := A.abs[0], B.abs[0]
+			if extended {
+				var ua, ub, va, vb Word
+				ua, ub = 1, 0
+				va, vb = 0, 1
+				even := true
+				for bWord != 0 {
+					q, r := aWord/bWord, aWord%bWord
+					aWord, bWord = bWord, r
+					ua, ub = ub, ua+q*ub
+					va, vb = vb, va+q*vb
+					even = !even
+				}
+
+				t.abs = t.abs.setWord(ua)
+				s.abs = s.abs.setWord(va)
+				t.neg = !even
+				s.neg = even
+
+				t.Mul(Ua, t)
+				s.Mul(Ub, s)
+
+				Ua.Add(t, s)
+			} else {
+				for bWord != 0 {
+					aWord, bWord = bWord, aWord%bWord
+				}
+			}
+			A.abs[0] = aWord
+		}
+	}
+	negA := a.neg
+	if y != nil {
+		// avoid aliasing b needed in the division below
+		if y == b {
+			B.Set(b)
+		} else {
+			B = b
+		}
+		// y = (z - a*x)/b
+		y.Mul(a, Ua) // y can safely alias a
+		if negA {
+			y.neg = !y.neg
+		}
+		y.Sub(A, y)
+		y.Div(y, B)
+	}
+
+	if x != nil {
+		*x = *Ua
+		if negA {
+			x.neg = !x.neg
+		}
+	}
+
+	*z = *A
+
+	return z
+}
+
+// Rand sets z to a pseudo-random number in [0, n) and returns z.
+//
+// As this uses the math/rand package, it must not be used for
+// security-sensitive work. Use crypto/rand.Int instead.
+func (z *Int) Rand(rnd *rand.Rand, n *Int) *Int {
+	// z.neg is not modified before the if check, because z and n might alias.
+	if n.neg || len(n.abs) == 0 {
+		z.neg = false
+		z.abs = nil
+		return z
+	}
+	z.neg = false
+	z.abs = z.abs.random(rnd, n.abs, n.abs.bitLen())
+	return z
+}
+
+// ModInverse sets z to the multiplicative inverse of g in the ring ℤ/nℤ
+// and returns z. If g and n are not relatively prime, g has no multiplicative
+// inverse in the ring ℤ/nℤ.  In this case, z is unchanged and the return value
+// is nil. If n == 0, a division-by-zero run-time panic occurs.
+func (z *Int) ModInverse(g, n *Int) *Int {
+	// GCD expects parameters a and b to be > 0.
+	if n.neg {
+		var n2 Int
+		n = n2.Neg(n)
+	}
+	if g.neg {
+		var g2 Int
+		g = g2.Mod(g, n)
+	}
+	var d, x Int
+	d.GCD(&x, nil, g, n)
+
+	// if and only if d==1, g and n are relatively prime
+	if d.Cmp(intOne) != 0 {
+		return nil
+	}
+
+	// x and y are such that g*x + n*y = 1, therefore x is the inverse element,
+	// but it may be negative, so convert to the range 0 <= z < |n|
+	if x.neg {
+		z.Add(&x, n)
+	} else {
+		z.Set(&x)
+	}
+	return z
+}
+
+// Jacobi returns the Jacobi symbol (x/y), either +1, -1, or 0.
+// The y argument must be an odd integer.
+func Jacobi(x, y *Int) int {
+	if len(y.abs) == 0 || y.abs[0]&1 == 0 {
+		panic(fmt.Sprintf("big: invalid 2nd argument to Int.Jacobi: need odd integer but got %s", y.String()))
+	}
+
+	// We use the formulation described in chapter 2, section 2.4,
+	// "The Yacas Book of Algorithms":
+	// http://yacas.sourceforge.net/Algo.book.pdf
+
+	var a, b, c Int
+	a.Set(x)
+	b.Set(y)
+	j := 1
+
+	if b.neg {
+		if a.neg {
+			j = -1
+		}
+		b.neg = false
+	}
+
+	for {
+		if b.Cmp(intOne) == 0 {
+			return j
+		}
+		if len(a.abs) == 0 {
+			return 0
+		}
+		a.Mod(&a, &b)
+		if len(a.abs) == 0 {
+			return 0
+		}
+		// a > 0
+
+		// handle factors of 2 in 'a'
+		s := a.abs.trailingZeroBits()
+		if s&1 != 0 {
+			bmod8 := b.abs[0] & 7
+			if bmod8 == 3 || bmod8 == 5 {
+				j = -j
+			}
+		}
+		c.Rsh(&a, s) // a = 2^s*c
+
+		// swap numerator and denominator
+		if b.abs[0]&3 == 3 && c.abs[0]&3 == 3 {
+			j = -j
+		}
+		a.Set(&b)
+		b.Set(&c)
+	}
+}
+
+// modSqrt3Mod4 uses the identity
+//
+//	   (a^((p+1)/4))^2  mod p
+//	== u^(p+1)          mod p
+//	== u^2              mod p
+//
+// to calculate the square root of any quadratic residue mod p quickly for 3
+// mod 4 primes.
+func (z *Int) modSqrt3Mod4Prime(x, p *Int) *Int {
+	e := new(Int).Add(p, intOne) // e = p + 1
+	e.Rsh(e, 2)                  // e = (p + 1) / 4
+	z.Exp(x, e, p)               // z = x^e mod p
+	return z
+}
+
+// modSqrt5Mod8 uses Atkin's observation that 2 is not a square mod p
+//
+//	alpha ==  (2*a)^((p-5)/8)    mod p
+//	beta  ==  2*a*alpha^2        mod p  is a square root of -1
+//	b     ==  a*alpha*(beta-1)   mod p  is a square root of a
+//
+// to calculate the square root of any quadratic residue mod p quickly for 5
+// mod 8 primes.
+func (z *Int) modSqrt5Mod8Prime(x, p *Int) *Int {
+	// p == 5 mod 8 implies p = e*8 + 5
+	// e is the quotient and 5 the remainder on division by 8
+	e := new(Int).Rsh(p, 3)  // e = (p - 5) / 8
+	tx := new(Int).Lsh(x, 1) // tx = 2*x
+	alpha := new(Int).Exp(tx, e, p)
+	beta := new(Int).Mul(alpha, alpha)
+	beta.Mod(beta, p)
+	beta.Mul(beta, tx)
+	beta.Mod(beta, p)
+	beta.Sub(beta, intOne)
+	beta.Mul(beta, x)
+	beta.Mod(beta, p)
+	beta.Mul(beta, alpha)
+	z.Mod(beta, p)
+	return z
+}
+
+// modSqrtTonelliShanks uses the Tonelli-Shanks algorithm to find the square
+// root of a quadratic residue modulo any prime.
+func (z *Int) modSqrtTonelliShanks(x, p *Int) *Int {
+	// Break p-1 into s*2^e such that s is odd.
+	var s Int
+	s.Sub(p, intOne)
+	e := s.abs.trailingZeroBits()
+	s.Rsh(&s, e)
+
+	// find some non-square n
+	var n Int
+	n.SetInt64(2)
+	for Jacobi(&n, p) != -1 {
+		n.Add(&n, intOne)
+	}
+
+	// Core of the Tonelli-Shanks algorithm. Follows the description in
+	// section 6 of "Square roots from 1; 24, 51, 10 to Dan Shanks" by Ezra
+	// Brown:
+	// https://www.maa.org/sites/default/files/pdf/upload_library/22/Polya/07468342.di020786.02p0470a.pdf
+	var y, b, g, t Int
+	y.Add(&s, intOne)
+	y.Rsh(&y, 1)
+	y.Exp(x, &y, p)  // y = x^((s+1)/2)
+	b.Exp(x, &s, p)  // b = x^s
+	g.Exp(&n, &s, p) // g = n^s
+	r := e
+	for {
+		// find the least m such that ord_p(b) = 2^m
+		var m uint
+		t.Set(&b)
+		for t.Cmp(intOne) != 0 {
+			t.Mul(&t, &t).Mod(&t, p)
+			m++
+		}
+
+		if m == 0 {
+			return z.Set(&y)
+		}
+
+		t.SetInt64(0).SetBit(&t, int(r-m-1), 1).Exp(&g, &t, p)
+		// t = g^(2^(r-m-1)) mod p
+		g.Mul(&t, &t).Mod(&g, p) // g = g^(2^(r-m)) mod p
+		y.Mul(&y, &t).Mod(&y, p)
+		b.Mul(&b, &g).Mod(&b, p)
+		r = m
+	}
+}
+
+// ModSqrt sets z to a square root of x mod p if such a square root exists, and
+// returns z. The modulus p must be an odd prime. If x is not a square mod p,
+// ModSqrt leaves z unchanged and returns nil. This function panics if p is
+// not an odd integer, its behavior is undefined if p is odd but not prime.
+func (z *Int) ModSqrt(x, p *Int) *Int {
+	switch Jacobi(x, p) {
+	case -1:
+		return nil // x is not a square mod p
+	case 0:
+		return z.SetInt64(0) // sqrt(0) mod p = 0
+	case 1:
+		break
+	}
+	if x.neg || x.Cmp(p) >= 0 { // ensure 0 <= x < p
+		x = new(Int).Mod(x, p)
+	}
+
+	switch {
+	case p.abs[0]%4 == 3:
+		// Check whether p is 3 mod 4, and if so, use the faster algorithm.
+		return z.modSqrt3Mod4Prime(x, p)
+	case p.abs[0]%8 == 5:
+		// Check whether p is 5 mod 8, use Atkin's algorithm.
+		return z.modSqrt5Mod8Prime(x, p)
+	default:
+		// Otherwise, use Tonelli-Shanks.
+		return z.modSqrtTonelliShanks(x, p)
+	}
+}
+
+// Lsh sets z = x << n and returns z.
+func (z *Int) Lsh(x *Int, n uint) *Int {
+	z.abs = z.abs.shl(x.abs, n)
+	z.neg = x.neg
+	return z
+}
+
+// Rsh sets z = x >> n and returns z.
+func (z *Int) Rsh(x *Int, n uint) *Int {
+	if x.neg {
+		// (-x) >> s == ^(x-1) >> s == ^((x-1) >> s) == -(((x-1) >> s) + 1)
+		t := z.abs.sub(x.abs, natOne) // no underflow because |x| > 0
+		t = t.shr(t, n)
+		z.abs = t.add(t, natOne)
+		z.neg = true // z cannot be zero if x is negative
+		return z
+	}
+
+	z.abs = z.abs.shr(x.abs, n)
+	z.neg = false
+	return z
+}
+
+// Bit returns the value of the i'th bit of x. That is, it
+// returns (x>>i)&1. The bit index i must be >= 0.
+func (x *Int) Bit(i int) uint {
+	if i == 0 {
+		// optimization for common case: odd/even test of x
+		if len(x.abs) > 0 {
+			return uint(x.abs[0] & 1) // bit 0 is same for -x
+		}
+		return 0
+	}
+	if i < 0 {
+		panic("negative bit index")
+	}
+	if x.neg {
+		t := nat(nil).sub(x.abs, natOne)
+		return t.bit(uint(i)) ^ 1
+	}
+
+	return x.abs.bit(uint(i))
+}
+
+// SetBit sets z to x, with x's i'th bit set to b (0 or 1).
+// That is, if b is 1 SetBit sets z = x | (1 << i);
+// if b is 0 SetBit sets z = x &^ (1 << i). If b is not 0 or 1,
+// SetBit will panic.
+func (z *Int) SetBit(x *Int, i int, b uint) *Int {
+	if i < 0 {
+		panic("negative bit index")
+	}
+	if x.neg {
+		t := z.abs.sub(x.abs, natOne)
+		t = t.setBit(t, uint(i), b^1)
+		z.abs = t.add(t, natOne)
+		z.neg = len(z.abs) > 0
+		return z
+	}
+	z.abs = z.abs.setBit(x.abs, uint(i), b)
+	z.neg = false
+	return z
+}
+
+// And sets z = x & y and returns z.
+func (z *Int) And(x, y *Int) *Int {
+	if x.neg == y.neg {
+		if x.neg {
+			// (-x) & (-y) == ^(x-1) & ^(y-1) == ^((x-1) | (y-1)) == -(((x-1) | (y-1)) + 1)
+			x1 := nat(nil).sub(x.abs, natOne)
+			y1 := nat(nil).sub(y.abs, natOne)
+			z.abs = z.abs.add(z.abs.or(x1, y1), natOne)
+			z.neg = true // z cannot be zero if x and y are negative
+			return z
+		}
+
+		// x & y == x & y
+		z.abs = z.abs.and(x.abs, y.abs)
+		z.neg = false
+		return z
+	}
+
+	// x.neg != y.neg
+	if x.neg {
+		x, y = y, x // & is symmetric
+	}
+
+	// x & (-y) == x & ^(y-1) == x &^ (y-1)
+	y1 := nat(nil).sub(y.abs, natOne)
+	z.abs = z.abs.andNot(x.abs, y1)
+	z.neg = false
+	return z
+}
+
+// AndNot sets z = x &^ y and returns z.
+func (z *Int) AndNot(x, y *Int) *Int {
+	if x.neg == y.neg {
+		if x.neg {
+			// (-x) &^ (-y) == ^(x-1) &^ ^(y-1) == ^(x-1) & (y-1) == (y-1) &^ (x-1)
+			x1 := nat(nil).sub(x.abs, natOne)
+			y1 := nat(nil).sub(y.abs, natOne)
+			z.abs = z.abs.andNot(y1, x1)
+			z.neg = false
+			return z
+		}
+
+		// x &^ y == x &^ y
+		z.abs = z.abs.andNot(x.abs, y.abs)
+		z.neg = false
+		return z
+	}
+
+	if x.neg {
+		// (-x) &^ y == ^(x-1) &^ y == ^(x-1) & ^y == ^((x-1) | y) == -(((x-1) | y) + 1)
+		x1 := nat(nil).sub(x.abs, natOne)
+		z.abs = z.abs.add(z.abs.or(x1, y.abs), natOne)
+		z.neg = true // z cannot be zero if x is negative and y is positive
+		return z
+	}
+
+	// x &^ (-y) == x &^ ^(y-1) == x & (y-1)
+	y1 := nat(nil).sub(y.abs, natOne)
+	z.abs = z.abs.and(x.abs, y1)
+	z.neg = false
+	return z
+}
+
+// Or sets z = x | y and returns z.
+func (z *Int) Or(x, y *Int) *Int {
+	if x.neg == y.neg {
+		if x.neg {
+			// (-x) | (-y) == ^(x-1) | ^(y-1) == ^((x-1) & (y-1)) == -(((x-1) & (y-1)) + 1)
+			x1 := nat(nil).sub(x.abs, natOne)
+			y1 := nat(nil).sub(y.abs, natOne)
+			z.abs = z.abs.add(z.abs.and(x1, y1), natOne)
+			z.neg = true // z cannot be zero if x and y are negative
+			return z
+		}
+
+		// x | y == x | y
+		z.abs = z.abs.or(x.abs, y.abs)
+		z.neg = false
+		return z
+	}
+
+	// x.neg != y.neg
+	if x.neg {
+		x, y = y, x // | is symmetric
+	}
+
+	// x | (-y) == x | ^(y-1) == ^((y-1) &^ x) == -(^((y-1) &^ x) + 1)
+	y1 := nat(nil).sub(y.abs, natOne)
+	z.abs = z.abs.add(z.abs.andNot(y1, x.abs), natOne)
+	z.neg = true // z cannot be zero if one of x or y is negative
+	return z
+}
+
+// Xor sets z = x ^ y and returns z.
+func (z *Int) Xor(x, y *Int) *Int {
+	if x.neg == y.neg {
+		if x.neg {
+			// (-x) ^ (-y) == ^(x-1) ^ ^(y-1) == (x-1) ^ (y-1)
+			x1 := nat(nil).sub(x.abs, natOne)
+			y1 := nat(nil).sub(y.abs, natOne)
+			z.abs = z.abs.xor(x1, y1)
+			z.neg = false
+			return z
+		}
+
+		// x ^ y == x ^ y
+		z.abs = z.abs.xor(x.abs, y.abs)
+		z.neg = false
+		return z
+	}
+
+	// x.neg != y.neg
+	if x.neg {
+		x, y = y, x // ^ is symmetric
+	}
+
+	// x ^ (-y) == x ^ ^(y-1) == ^(x ^ (y-1)) == -((x ^ (y-1)) + 1)
+	y1 := nat(nil).sub(y.abs, natOne)
+	z.abs = z.abs.add(z.abs.xor(x.abs, y1), natOne)
+	z.neg = true // z cannot be zero if only one of x or y is negative
+	return z
+}
+
+// Not sets z = ^x and returns z.
+func (z *Int) Not(x *Int) *Int {
+	if x.neg {
+		// ^(-x) == ^(^(x-1)) == x-1
+		z.abs = z.abs.sub(x.abs, natOne)
+		z.neg = false
+		return z
+	}
+
+	// ^x == -x-1 == -(x+1)
+	z.abs = z.abs.add(x.abs, natOne)
+	z.neg = true // z cannot be zero if x is positive
+	return z
+}
+
+// Sqrt sets z to ⌊√x⌋, the largest integer such that z² ≤ x, and returns z.
+// It panics if x is negative.
+func (z *Int) Sqrt(x *Int) *Int {
+	if x.neg {
+		panic("square root of negative number")
+	}
+	z.neg = false
+	z.abs = z.abs.sqrt(x.abs)
+	return z
+}
diff --git a/contrib/go/_std_1.19/src/math/big/intconv.go b/contrib/go/_std_1.19/src/math/big/intconv.go
new file mode 100644
index 0000000000..a3a4023caa
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/big/intconv.go
@@ -0,0 +1,255 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements int-to-string conversion functions.
+
+package big
+
+import (
+	"errors"
+	"fmt"
+	"io"
+)
+
+// Text returns the string representation of x in the given base.
+// Base must be between 2 and 62, inclusive. The result uses the
+// lower-case letters 'a' to 'z' for digit values 10 to 35, and
+// the upper-case letters 'A' to 'Z' for digit values 36 to 61.
+// No prefix (such as "0x") is added to the string. If x is a nil
+// pointer it returns "<nil>".
+func (x *Int) Text(base int) string {
+	if x == nil {
+		return "<nil>"
+	}
+	return string(x.abs.itoa(x.neg, base))
+}
+
+// Append appends the string representation of x, as generated by
+// x.Text(base), to buf and returns the extended buffer.
+func (x *Int) Append(buf []byte, base int) []byte {
+	if x == nil {
+		return append(buf, "<nil>"...)
+	}
+	return append(buf, x.abs.itoa(x.neg, base)...)
+}
+
+// String returns the decimal representation of x as generated by
+// x.Text(10).
+func (x *Int) String() string {
+	return x.Text(10)
+}
+
+// write count copies of text to s
+func writeMultiple(s fmt.State, text string, count int) {
+	if len(text) > 0 {
+		b := []byte(text)
+		for ; count > 0; count-- {
+			s.Write(b)
+		}
+	}
+}
+
+var _ fmt.Formatter = intOne // *Int must implement fmt.Formatter
+
+// Format implements fmt.Formatter. It accepts the formats
+// 'b' (binary), 'o' (octal with 0 prefix), 'O' (octal with 0o prefix),
+// 'd' (decimal), 'x' (lowercase hexadecimal), and
+// 'X' (uppercase hexadecimal).
+// Also supported are the full suite of package fmt's format
+// flags for integral types, including '+' and ' ' for sign
+// control, '#' for leading zero in octal and for hexadecimal,
+// a leading "0x" or "0X" for "%#x" and "%#X" respectively,
+// specification of minimum digits precision, output field
+// width, space or zero padding, and '-' for left or right
+// justification.
+func (x *Int) Format(s fmt.State, ch rune) {
+	// determine base
+	var base int
+	switch ch {
+	case 'b':
+		base = 2
+	case 'o', 'O':
+		base = 8
+	case 'd', 's', 'v':
+		base = 10
+	case 'x', 'X':
+		base = 16
+	default:
+		// unknown format
+		fmt.Fprintf(s, "%%!%c(big.Int=%s)", ch, x.String())
+		return
+	}
+
+	if x == nil {
+		fmt.Fprint(s, "<nil>")
+		return
+	}
+
+	// determine sign character
+	sign := ""
+	switch {
+	case x.neg:
+		sign = "-"
+	case s.Flag('+'): // supersedes ' ' when both specified
+		sign = "+"
+	case s.Flag(' '):
+		sign = " "
+	}
+
+	// determine prefix characters for indicating output base
+	prefix := ""
+	if s.Flag('#') {
+		switch ch {
+		case 'b': // binary
+			prefix = "0b"
+		case 'o': // octal
+			prefix = "0"
+		case 'x': // hexadecimal
+			prefix = "0x"
+		case 'X':
+			prefix = "0X"
+		}
+	}
+	if ch == 'O' {
+		prefix = "0o"
+	}
+
+	digits := x.abs.utoa(base)
+	if ch == 'X' {
+		// faster than bytes.ToUpper
+		for i, d := range digits {
+			if 'a' <= d && d <= 'z' {
+				digits[i] = 'A' + (d - 'a')
+			}
+		}
+	}
+
+	// number of characters for the three classes of number padding
+	var left int  // space characters to left of digits for right justification ("%8d")
+	var zeros int // zero characters (actually cs[0]) as left-most digits ("%.8d")
+	var right int // space characters to right of digits for left justification ("%-8d")
+
+	// determine number padding from precision: the least number of digits to output
+	precision, precisionSet := s.Precision()
+	if precisionSet {
+		switch {
+		case len(digits) < precision:
+			zeros = precision - len(digits) // count of zero padding
+		case len(digits) == 1 && digits[0] == '0' && precision == 0:
+			return // print nothing if zero value (x == 0) and zero precision ("." or ".0")
+		}
+	}
+
+	// determine field pad from width: the least number of characters to output
+	length := len(sign) + len(prefix) + zeros + len(digits)
+	if width, widthSet := s.Width(); widthSet && length < width { // pad as specified
+		switch d := width - length; {
+		case s.Flag('-'):
+			// pad on the right with spaces; supersedes '0' when both specified
+			right = d
+		case s.Flag('0') && !precisionSet:
+			// pad with zeros unless precision also specified
+			zeros = d
+		default:
+			// pad on the left with spaces
+			left = d
+		}
+	}
+
+	// print number as [left pad][sign][prefix][zero pad][digits][right pad]
+	writeMultiple(s, " ", left)
+	writeMultiple(s, sign, 1)
+	writeMultiple(s, prefix, 1)
+	writeMultiple(s, "0", zeros)
+	s.Write(digits)
+	writeMultiple(s, " ", right)
+}
+
+// scan sets z to the integer value corresponding to the longest possible prefix
+// read from r representing a signed integer number in a given conversion base.
+// It returns z, the actual conversion base used, and an error, if any. In the
+// error case, the value of z is undefined but the returned value is nil. The
+// syntax follows the syntax of integer literals in Go.
+//
+// The base argument must be 0 or a value from 2 through MaxBase. If the base
+// is 0, the string prefix determines the actual conversion base. A prefix of
+// “0b” or “0B” selects base 2; a “0”, “0o”, or “0O” prefix selects
+// base 8, and a “0x” or “0X” prefix selects base 16. Otherwise the selected
+// base is 10.
+func (z *Int) scan(r io.ByteScanner, base int) (*Int, int, error) {
+	// determine sign
+	neg, err := scanSign(r)
+	if err != nil {
+		return nil, 0, err
+	}
+
+	// determine mantissa
+	z.abs, base, _, err = z.abs.scan(r, base, false)
+	if err != nil {
+		return nil, base, err
+	}
+	z.neg = len(z.abs) > 0 && neg // 0 has no sign
+
+	return z, base, nil
+}
+
+func scanSign(r io.ByteScanner) (neg bool, err error) {
+	var ch byte
+	if ch, err = r.ReadByte(); err != nil {
+		return false, err
+	}
+	switch ch {
+	case '-':
+		neg = true
+	case '+':
+		// nothing to do
+	default:
+		r.UnreadByte()
+	}
+	return
+}
+
+// byteReader is a local wrapper around fmt.ScanState;
+// it implements the ByteReader interface.
+type byteReader struct {
+	fmt.ScanState
+}
+
+func (r byteReader) ReadByte() (byte, error) {
+	ch, size, err := r.ReadRune()
+	if size != 1 && err == nil {
+		err = fmt.Errorf("invalid rune %#U", ch)
+	}
+	return byte(ch), err
+}
+
+func (r byteReader) UnreadByte() error {
+	return r.UnreadRune()
+}
+
+var _ fmt.Scanner = intOne // *Int must implement fmt.Scanner
+
+// Scan is a support routine for fmt.Scanner; it sets z to the value of
+// the scanned number. It accepts the formats 'b' (binary), 'o' (octal),
+// 'd' (decimal), 'x' (lowercase hexadecimal), and 'X' (uppercase hexadecimal).
+func (z *Int) Scan(s fmt.ScanState, ch rune) error {
+	s.SkipSpace() // skip leading space characters
+	base := 0
+	switch ch {
+	case 'b':
+		base = 2
+	case 'o':
+		base = 8
+	case 'd':
+		base = 10
+	case 'x', 'X':
+		base = 16
+	case 's', 'v':
+		// let scan determine the base
+	default:
+		return errors.New("Int.Scan: invalid verb")
+	}
+	_, _, err := z.scan(byteReader{s}, base)
+	return err
+}
diff --git a/contrib/go/_std_1.19/src/math/big/intmarsh.go b/contrib/go/_std_1.19/src/math/big/intmarsh.go
new file mode 100644
index 0000000000..ce429ffc11
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/big/intmarsh.go
@@ -0,0 +1,83 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements encoding/decoding of Ints.
+
+package big
+
+import (
+	"bytes"
+	"fmt"
+)
+
+// Gob codec version. Permits backward-compatible changes to the encoding.
+const intGobVersion byte = 1
+
+// GobEncode implements the gob.GobEncoder interface.
+func (x *Int) GobEncode() ([]byte, error) {
+	if x == nil {
+		return nil, nil
+	}
+	buf := make([]byte, 1+len(x.abs)*_S) // extra byte for version and sign bit
+	i := x.abs.bytes(buf) - 1            // i >= 0
+	b := intGobVersion << 1              // make space for sign bit
+	if x.neg {
+		b |= 1
+	}
+	buf[i] = b
+	return buf[i:], nil
+}
+
+// GobDecode implements the gob.GobDecoder interface.
+func (z *Int) GobDecode(buf []byte) error {
+	if len(buf) == 0 {
+		// Other side sent a nil or default value.
+		*z = Int{}
+		return nil
+	}
+	b := buf[0]
+	if b>>1 != intGobVersion {
+		return fmt.Errorf("Int.GobDecode: encoding version %d not supported", b>>1)
+	}
+	z.neg = b&1 != 0
+	z.abs = z.abs.setBytes(buf[1:])
+	return nil
+}
+
+// MarshalText implements the encoding.TextMarshaler interface.
+func (x *Int) MarshalText() (text []byte, err error) {
+	if x == nil {
+		return []byte("<nil>"), nil
+	}
+	return x.abs.itoa(x.neg, 10), nil
+}
+
+// UnmarshalText implements the encoding.TextUnmarshaler interface.
+func (z *Int) UnmarshalText(text []byte) error {
+	if _, ok := z.setFromScanner(bytes.NewReader(text), 0); !ok {
+		return fmt.Errorf("math/big: cannot unmarshal %q into a *big.Int", text)
+	}
+	return nil
+}
+
+// The JSON marshalers are only here for API backward compatibility
+// (programs that explicitly look for these two methods). JSON works
+// fine with the TextMarshaler only.
+
+// MarshalJSON implements the json.Marshaler interface.
+func (x *Int) MarshalJSON() ([]byte, error) {
+	if x == nil {
+		return []byte("null"), nil
+	}
+	return x.abs.itoa(x.neg, 10), nil
+}
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (z *Int) UnmarshalJSON(text []byte) error {
+	// Ignore null, like in the main JSON package.
+	if string(text) == "null" {
+		return nil
+	}
+	return z.UnmarshalText(text)
+}
diff --git a/contrib/go/_std_1.19/src/math/big/nat.go b/contrib/go/_std_1.19/src/math/big/nat.go
new file mode 100644
index 0000000000..5cc42b80dc
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/big/nat.go
@@ -0,0 +1,1244 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements unsigned multi-precision integers (natural
+// numbers). They are the building blocks for the implementation
+// of signed integers, rationals, and floating-point numbers.
+//
+// Caution: This implementation relies on the function "alias"
+//          which assumes that (nat) slice capacities are never
+//          changed (no 3-operand slice expressions). If that
+//          changes, alias needs to be updated for correctness.
+
+package big
+
+import (
+	"encoding/binary"
+	"math/bits"
+	"math/rand"
+	"sync"
+)
+
+// An unsigned integer x of the form
+//
+//	x = x[n-1]*_B^(n-1) + x[n-2]*_B^(n-2) + ... + x[1]*_B + x[0]
+//
+// with 0 <= x[i] < _B and 0 <= i < n is stored in a slice of length n,
+// with the digits x[i] as the slice elements.
+//
+// A number is normalized if the slice contains no leading 0 digits.
+// During arithmetic operations, denormalized values may occur but are
+// always normalized before returning the final result. The normalized
+// representation of 0 is the empty or nil slice (length = 0).
+type nat []Word
+
+var (
+	natOne  = nat{1}
+	natTwo  = nat{2}
+	natFive = nat{5}
+	natTen  = nat{10}
+)
+
+func (z nat) clear() {
+	for i := range z {
+		z[i] = 0
+	}
+}
+
+func (z nat) norm() nat {
+	i := len(z)
+	for i > 0 && z[i-1] == 0 {
+		i--
+	}
+	return z[0:i]
+}
+
+func (z nat) make(n int) nat {
+	if n <= cap(z) {
+		return z[:n] // reuse z
+	}
+	if n == 1 {
+		// Most nats start small and stay that way; don't over-allocate.
+		return make(nat, 1)
+	}
+	// Choosing a good value for e has significant performance impact
+	// because it increases the chance that a value can be reused.
+	const e = 4 // extra capacity
+	return make(nat, n, n+e)
+}
+
+func (z nat) setWord(x Word) nat {
+	if x == 0 {
+		return z[:0]
+	}
+	z = z.make(1)
+	z[0] = x
+	return z
+}
+
+func (z nat) setUint64(x uint64) nat {
+	// single-word value
+	if w := Word(x); uint64(w) == x {
+		return z.setWord(w)
+	}
+	// 2-word value
+	z = z.make(2)
+	z[1] = Word(x >> 32)
+	z[0] = Word(x)
+	return z
+}
+
+func (z nat) set(x nat) nat {
+	z = z.make(len(x))
+	copy(z, x)
+	return z
+}
+
+func (z nat) add(x, y nat) nat {
+	m := len(x)
+	n := len(y)
+
+	switch {
+	case m < n:
+		return z.add(y, x)
+	case m == 0:
+		// n == 0 because m >= n; result is 0
+		return z[:0]
+	case n == 0:
+		// result is x
+		return z.set(x)
+	}
+	// m > 0
+
+	z = z.make(m + 1)
+	c := addVV(z[0:n], x, y)
+	if m > n {
+		c = addVW(z[n:m], x[n:], c)
+	}
+	z[m] = c
+
+	return z.norm()
+}
+
+func (z nat) sub(x, y nat) nat {
+	m := len(x)
+	n := len(y)
+
+	switch {
+	case m < n:
+		panic("underflow")
+	case m == 0:
+		// n == 0 because m >= n; result is 0
+		return z[:0]
+	case n == 0:
+		// result is x
+		return z.set(x)
+	}
+	// m > 0
+
+	z = z.make(m)
+	c := subVV(z[0:n], x, y)
+	if m > n {
+		c = subVW(z[n:], x[n:], c)
+	}
+	if c != 0 {
+		panic("underflow")
+	}
+
+	return z.norm()
+}
+
+func (x nat) cmp(y nat) (r int) {
+	m := len(x)
+	n := len(y)
+	if m != n || m == 0 {
+		switch {
+		case m < n:
+			r = -1
+		case m > n:
+			r = 1
+		}
+		return
+	}
+
+	i := m - 1
+	for i > 0 && x[i] == y[i] {
+		i--
+	}
+
+	switch {
+	case x[i] < y[i]:
+		r = -1
+	case x[i] > y[i]:
+		r = 1
+	}
+	return
+}
+
+func (z nat) mulAddWW(x nat, y, r Word) nat {
+	m := len(x)
+	if m == 0 || y == 0 {
+		return z.setWord(r) // result is r
+	}
+	// m > 0
+
+	z = z.make(m + 1)
+	z[m] = mulAddVWW(z[0:m], x, y, r)
+
+	return z.norm()
+}
+
+// basicMul multiplies x and y and leaves the result in z.
+// The (non-normalized) result is placed in z[0 : len(x) + len(y)].
+func basicMul(z, x, y nat) {
+	z[0 : len(x)+len(y)].clear() // initialize z
+	for i, d := range y {
+		if d != 0 {
+			z[len(x)+i] = addMulVVW(z[i:i+len(x)], x, d)
+		}
+	}
+}
+
+// montgomery computes z mod m = x*y*2**(-n*_W) mod m,
+// assuming k = -1/m mod 2**_W.
+// z is used for storing the result which is returned;
+// z must not alias x, y or m.
+// See Gueron, "Efficient Software Implementations of Modular Exponentiation".
+// https://eprint.iacr.org/2011/239.pdf
+// In the terminology of that paper, this is an "Almost Montgomery Multiplication":
+// x and y are required to satisfy 0 <= z < 2**(n*_W) and then the result
+// z is guaranteed to satisfy 0 <= z < 2**(n*_W), but it may not be < m.
+func (z nat) montgomery(x, y, m nat, k Word, n int) nat {
+	// This code assumes x, y, m are all the same length, n.
+	// (required by addMulVVW and the for loop).
+	// It also assumes that x, y are already reduced mod m,
+	// or else the result will not be properly reduced.
+	if len(x) != n || len(y) != n || len(m) != n {
+		panic("math/big: mismatched montgomery number lengths")
+	}
+	z = z.make(n * 2)
+	z.clear()
+	var c Word
+	for i := 0; i < n; i++ {
+		d := y[i]
+		c2 := addMulVVW(z[i:n+i], x, d)
+		t := z[i] * k
+		c3 := addMulVVW(z[i:n+i], m, t)
+		cx := c + c2
+		cy := cx + c3
+		z[n+i] = cy
+		if cx < c2 || cy < c3 {
+			c = 1
+		} else {
+			c = 0
+		}
+	}
+	if c != 0 {
+		subVV(z[:n], z[n:], m)
+	} else {
+		copy(z[:n], z[n:])
+	}
+	return z[:n]
+}
+
+// Fast version of z[0:n+n>>1].add(z[0:n+n>>1], x[0:n]) w/o bounds checks.
+// Factored out for readability - do not use outside karatsuba.
+func karatsubaAdd(z, x nat, n int) {
+	if c := addVV(z[0:n], z, x); c != 0 {
+		addVW(z[n:n+n>>1], z[n:], c)
+	}
+}
+
+// Like karatsubaAdd, but does subtract.
+func karatsubaSub(z, x nat, n int) {
+	if c := subVV(z[0:n], z, x); c != 0 {
+		subVW(z[n:n+n>>1], z[n:], c)
+	}
+}
+
+// Operands that are shorter than karatsubaThreshold are multiplied using
+// "grade school" multiplication; for longer operands the Karatsuba algorithm
+// is used.
+var karatsubaThreshold = 40 // computed by calibrate_test.go
+
+// karatsuba multiplies x and y and leaves the result in z.
+// Both x and y must have the same length n and n must be a
+// power of 2. The result vector z must have len(z) >= 6*n.
+// The (non-normalized) result is placed in z[0 : 2*n].
+func karatsuba(z, x, y nat) {
+	n := len(y)
+
+	// Switch to basic multiplication if numbers are odd or small.
+	// (n is always even if karatsubaThreshold is even, but be
+	// conservative)
+	if n&1 != 0 || n < karatsubaThreshold || n < 2 {
+		basicMul(z, x, y)
+		return
+	}
+	// n&1 == 0 && n >= karatsubaThreshold && n >= 2
+
+	// Karatsuba multiplication is based on the observation that
+	// for two numbers x and y with:
+	//
+	//   x = x1*b + x0
+	//   y = y1*b + y0
+	//
+	// the product x*y can be obtained with 3 products z2, z1, z0
+	// instead of 4:
+	//
+	//   x*y = x1*y1*b*b + (x1*y0 + x0*y1)*b + x0*y0
+	//       =    z2*b*b +              z1*b +    z0
+	//
+	// with:
+	//
+	//   xd = x1 - x0
+	//   yd = y0 - y1
+	//
+	//   z1 =      xd*yd                    + z2 + z0
+	//      = (x1-x0)*(y0 - y1)             + z2 + z0
+	//      = x1*y0 - x1*y1 - x0*y0 + x0*y1 + z2 + z0
+	//      = x1*y0 -    z2 -    z0 + x0*y1 + z2 + z0
+	//      = x1*y0                 + x0*y1
+
+	// split x, y into "digits"
+	n2 := n >> 1              // n2 >= 1
+	x1, x0 := x[n2:], x[0:n2] // x = x1*b + y0
+	y1, y0 := y[n2:], y[0:n2] // y = y1*b + y0
+
+	// z is used for the result and temporary storage:
+	//
+	//   6*n     5*n     4*n     3*n     2*n     1*n     0*n
+	// z = [z2 copy|z0 copy| xd*yd | yd:xd | x1*y1 | x0*y0 ]
+	//
+	// For each recursive call of karatsuba, an unused slice of
+	// z is passed in that has (at least) half the length of the
+	// caller's z.
+
+	// compute z0 and z2 with the result "in place" in z
+	karatsuba(z, x0, y0)     // z0 = x0*y0
+	karatsuba(z[n:], x1, y1) // z2 = x1*y1
+
+	// compute xd (or the negative value if underflow occurs)
+	s := 1 // sign of product xd*yd
+	xd := z[2*n : 2*n+n2]
+	if subVV(xd, x1, x0) != 0 { // x1-x0
+		s = -s
+		subVV(xd, x0, x1) // x0-x1
+	}
+
+	// compute yd (or the negative value if underflow occurs)
+	yd := z[2*n+n2 : 3*n]
+	if subVV(yd, y0, y1) != 0 { // y0-y1
+		s = -s
+		subVV(yd, y1, y0) // y1-y0
+	}
+
+	// p = (x1-x0)*(y0-y1) == x1*y0 - x1*y1 - x0*y0 + x0*y1 for s > 0
+	// p = (x0-x1)*(y0-y1) == x0*y0 - x0*y1 - x1*y0 + x1*y1 for s < 0
+	p := z[n*3:]
+	karatsuba(p, xd, yd)
+
+	// save original z2:z0
+	// (ok to use upper half of z since we're done recurring)
+	r := z[n*4:]
+	copy(r, z[:n*2])
+
+	// add up all partial products
+	//
+	//   2*n     n     0
+	// z = [ z2  | z0  ]
+	//   +    [ z0  ]
+	//   +    [ z2  ]
+	//   +    [  p  ]
+	//
+	karatsubaAdd(z[n2:], r, n)
+	karatsubaAdd(z[n2:], r[n:], n)
+	if s > 0 {
+		karatsubaAdd(z[n2:], p, n)
+	} else {
+		karatsubaSub(z[n2:], p, n)
+	}
+}
+
+// alias reports whether x and y share the same base array.
+//
+// Note: alias assumes that the capacity of underlying arrays
+// is never changed for nat values; i.e. that there are
+// no 3-operand slice expressions in this code (or worse,
+// reflect-based operations to the same effect).
+func alias(x, y nat) bool {
+	return cap(x) > 0 && cap(y) > 0 && &x[0:cap(x)][cap(x)-1] == &y[0:cap(y)][cap(y)-1]
+}
+
+// addAt implements z += x<<(_W*i); z must be long enough.
+// (we don't use nat.add because we need z to stay the same
+// slice, and we don't need to normalize z after each addition)
+func addAt(z, x nat, i int) {
+	if n := len(x); n > 0 {
+		if c := addVV(z[i:i+n], z[i:], x); c != 0 {
+			j := i + n
+			if j < len(z) {
+				addVW(z[j:], z[j:], c)
+			}
+		}
+	}
+}
+
+func max(x, y int) int {
+	if x > y {
+		return x
+	}
+	return y
+}
+
+// karatsubaLen computes an approximation to the maximum k <= n such that
+// k = p<<i for a number p <= threshold and an i >= 0. Thus, the
+// result is the largest number that can be divided repeatedly by 2 before
+// becoming about the value of threshold.
+func karatsubaLen(n, threshold int) int {
+	i := uint(0)
+	for n > threshold {
+		n >>= 1
+		i++
+	}
+	return n << i
+}
+
+func (z nat) mul(x, y nat) nat {
+	m := len(x)
+	n := len(y)
+
+	switch {
+	case m < n:
+		return z.mul(y, x)
+	case m == 0 || n == 0:
+		return z[:0]
+	case n == 1:
+		return z.mulAddWW(x, y[0], 0)
+	}
+	// m >= n > 1
+
+	// determine if z can be reused
+	if alias(z, x) || alias(z, y) {
+		z = nil // z is an alias for x or y - cannot reuse
+	}
+
+	// use basic multiplication if the numbers are small
+	if n < karatsubaThreshold {
+		z = z.make(m + n)
+		basicMul(z, x, y)
+		return z.norm()
+	}
+	// m >= n && n >= karatsubaThreshold && n >= 2
+
+	// determine Karatsuba length k such that
+	//
+	//   x = xh*b + x0  (0 <= x0 < b)
+	//   y = yh*b + y0  (0 <= y0 < b)
+	//   b = 1<<(_W*k)  ("base" of digits xi, yi)
+	//
+	k := karatsubaLen(n, karatsubaThreshold)
+	// k <= n
+
+	// multiply x0 and y0 via Karatsuba
+	x0 := x[0:k]              // x0 is not normalized
+	y0 := y[0:k]              // y0 is not normalized
+	z = z.make(max(6*k, m+n)) // enough space for karatsuba of x0*y0 and full result of x*y
+	karatsuba(z, x0, y0)
+	z = z[0 : m+n]  // z has final length but may be incomplete
+	z[2*k:].clear() // upper portion of z is garbage (and 2*k <= m+n since k <= n <= m)
+
+	// If xh != 0 or yh != 0, add the missing terms to z. For
+	//
+	//   xh = xi*b^i + ... + x2*b^2 + x1*b (0 <= xi < b)
+	//   yh =                         y1*b (0 <= y1 < b)
+	//
+	// the missing terms are
+	//
+	//   x0*y1*b and xi*y0*b^i, xi*y1*b^(i+1) for i > 0
+	//
+	// since all the yi for i > 1 are 0 by choice of k: If any of them
+	// were > 0, then yh >= b^2 and thus y >= b^2. Then k' = k*2 would
+	// be a larger valid threshold contradicting the assumption about k.
+	//
+	if k < n || m != n {
+		tp := getNat(3 * k)
+		t := *tp
+
+		// add x0*y1*b
+		x0 := x0.norm()
+		y1 := y[k:]       // y1 is normalized because y is
+		t = t.mul(x0, y1) // update t so we don't lose t's underlying array
+		addAt(z, t, k)
+
+		// add xi*y0<<i, xi*y1*b<<(i+k)
+		y0 := y0.norm()
+		for i := k; i < len(x); i += k {
+			xi := x[i:]
+			if len(xi) > k {
+				xi = xi[:k]
+			}
+			xi = xi.norm()
+			t = t.mul(xi, y0)
+			addAt(z, t, i)
+			t = t.mul(xi, y1)
+			addAt(z, t, i+k)
+		}
+
+		putNat(tp)
+	}
+
+	return z.norm()
+}
+
+// basicSqr sets z = x*x and is asymptotically faster than basicMul
+// by about a factor of 2, but slower for small arguments due to overhead.
+// Requirements: len(x) > 0, len(z) == 2*len(x)
+// The (non-normalized) result is placed in z.
+func basicSqr(z, x nat) {
+	n := len(x)
+	tp := getNat(2 * n)
+	t := *tp // temporary variable to hold the products
+	t.clear()
+	z[1], z[0] = mulWW(x[0], x[0]) // the initial square
+	for i := 1; i < n; i++ {
+		d := x[i]
+		// z collects the squares x[i] * x[i]
+		z[2*i+1], z[2*i] = mulWW(d, d)
+		// t collects the products x[i] * x[j] where j < i
+		t[2*i] = addMulVVW(t[i:2*i], x[0:i], d)
+	}
+	t[2*n-1] = shlVU(t[1:2*n-1], t[1:2*n-1], 1) // double the j < i products
+	addVV(z, z, t)                              // combine the result
+	putNat(tp)
+}
+
+// karatsubaSqr squares x and leaves the result in z.
+// len(x) must be a power of 2 and len(z) >= 6*len(x).
+// The (non-normalized) result is placed in z[0 : 2*len(x)].
+//
+// The algorithm and the layout of z are the same as for karatsuba.
+func karatsubaSqr(z, x nat) {
+	n := len(x)
+
+	if n&1 != 0 || n < karatsubaSqrThreshold || n < 2 {
+		basicSqr(z[:2*n], x)
+		return
+	}
+
+	n2 := n >> 1
+	x1, x0 := x[n2:], x[0:n2]
+
+	karatsubaSqr(z, x0)
+	karatsubaSqr(z[n:], x1)
+
+	// s = sign(xd*yd) == -1 for xd != 0; s == 1 for xd == 0
+	xd := z[2*n : 2*n+n2]
+	if subVV(xd, x1, x0) != 0 {
+		subVV(xd, x0, x1)
+	}
+
+	p := z[n*3:]
+	karatsubaSqr(p, xd)
+
+	r := z[n*4:]
+	copy(r, z[:n*2])
+
+	karatsubaAdd(z[n2:], r, n)
+	karatsubaAdd(z[n2:], r[n:], n)
+	karatsubaSub(z[n2:], p, n) // s == -1 for p != 0; s == 1 for p == 0
+}
+
+// Operands that are shorter than basicSqrThreshold are squared using
+// "grade school" multiplication; for operands longer than karatsubaSqrThreshold
+// we use the Karatsuba algorithm optimized for x == y.
+var basicSqrThreshold = 20      // computed by calibrate_test.go
+var karatsubaSqrThreshold = 260 // computed by calibrate_test.go
+
+// z = x*x
+func (z nat) sqr(x nat) nat {
+	n := len(x)
+	switch {
+	case n == 0:
+		return z[:0]
+	case n == 1:
+		d := x[0]
+		z = z.make(2)
+		z[1], z[0] = mulWW(d, d)
+		return z.norm()
+	}
+
+	if alias(z, x) {
+		z = nil // z is an alias for x - cannot reuse
+	}
+
+	if n < basicSqrThreshold {
+		z = z.make(2 * n)
+		basicMul(z, x, x)
+		return z.norm()
+	}
+	if n < karatsubaSqrThreshold {
+		z = z.make(2 * n)
+		basicSqr(z, x)
+		return z.norm()
+	}
+
+	// Use Karatsuba multiplication optimized for x == y.
+	// The algorithm and layout of z are the same as for mul.
+
+	// z = (x1*b + x0)^2 = x1^2*b^2 + 2*x1*x0*b + x0^2
+
+	k := karatsubaLen(n, karatsubaSqrThreshold)
+
+	x0 := x[0:k]
+	z = z.make(max(6*k, 2*n))
+	karatsubaSqr(z, x0) // z = x0^2
+	z = z[0 : 2*n]
+	z[2*k:].clear()
+
+	if k < n {
+		tp := getNat(2 * k)
+		t := *tp
+		x0 := x0.norm()
+		x1 := x[k:]
+		t = t.mul(x0, x1)
+		addAt(z, t, k)
+		addAt(z, t, k) // z = 2*x1*x0*b + x0^2
+		t = t.sqr(x1)
+		addAt(z, t, 2*k) // z = x1^2*b^2 + 2*x1*x0*b + x0^2
+		putNat(tp)
+	}
+
+	return z.norm()
+}
+
+// mulRange computes the product of all the unsigned integers in the
+// range [a, b] inclusively. If a > b (empty range), the result is 1.
+func (z nat) mulRange(a, b uint64) nat {
+	switch {
+	case a == 0:
+		// cut long ranges short (optimization)
+		return z.setUint64(0)
+	case a > b:
+		return z.setUint64(1)
+	case a == b:
+		return z.setUint64(a)
+	case a+1 == b:
+		return z.mul(nat(nil).setUint64(a), nat(nil).setUint64(b))
+	}
+	m := (a + b) / 2
+	return z.mul(nat(nil).mulRange(a, m), nat(nil).mulRange(m+1, b))
+}
+
+// getNat returns a *nat of len n. The contents may not be zero.
+// The pool holds *nat to avoid allocation when converting to interface{}.
+func getNat(n int) *nat {
+	var z *nat
+	if v := natPool.Get(); v != nil {
+		z = v.(*nat)
+	}
+	if z == nil {
+		z = new(nat)
+	}
+	*z = z.make(n)
+	return z
+}
+
+func putNat(x *nat) {
+	natPool.Put(x)
+}
+
+var natPool sync.Pool
+
+// Length of x in bits. x must be normalized.
+func (x nat) bitLen() int {
+	if i := len(x) - 1; i >= 0 {
+		return i*_W + bits.Len(uint(x[i]))
+	}
+	return 0
+}
+
+// trailingZeroBits returns the number of consecutive least significant zero
+// bits of x.
+func (x nat) trailingZeroBits() uint {
+	if len(x) == 0 {
+		return 0
+	}
+	var i uint
+	for x[i] == 0 {
+		i++
+	}
+	// x[i] != 0
+	return i*_W + uint(bits.TrailingZeros(uint(x[i])))
+}
+
+func same(x, y nat) bool {
+	return len(x) == len(y) && len(x) > 0 && &x[0] == &y[0]
+}
+
+// z = x << s
+func (z nat) shl(x nat, s uint) nat {
+	if s == 0 {
+		if same(z, x) {
+			return z
+		}
+		if !alias(z, x) {
+			return z.set(x)
+		}
+	}
+
+	m := len(x)
+	if m == 0 {
+		return z[:0]
+	}
+	// m > 0
+
+	n := m + int(s/_W)
+	z = z.make(n + 1)
+	z[n] = shlVU(z[n-m:n], x, s%_W)
+	z[0 : n-m].clear()
+
+	return z.norm()
+}
+
+// z = x >> s
+func (z nat) shr(x nat, s uint) nat {
+	if s == 0 {
+		if same(z, x) {
+			return z
+		}
+		if !alias(z, x) {
+			return z.set(x)
+		}
+	}
+
+	m := len(x)
+	n := m - int(s/_W)
+	if n <= 0 {
+		return z[:0]
+	}
+	// n > 0
+
+	z = z.make(n)
+	shrVU(z, x[m-n:], s%_W)
+
+	return z.norm()
+}
+
+func (z nat) setBit(x nat, i uint, b uint) nat {
+	j := int(i / _W)
+	m := Word(1) << (i % _W)
+	n := len(x)
+	switch b {
+	case 0:
+		z = z.make(n)
+		copy(z, x)
+		if j >= n {
+			// no need to grow
+			return z
+		}
+		z[j] &^= m
+		return z.norm()
+	case 1:
+		if j >= n {
+			z = z.make(j + 1)
+			z[n:].clear()
+		} else {
+			z = z.make(n)
+		}
+		copy(z, x)
+		z[j] |= m
+		// no need to normalize
+		return z
+	}
+	panic("set bit is not 0 or 1")
+}
+
+// bit returns the value of the i'th bit, with lsb == bit 0.
+func (x nat) bit(i uint) uint {
+	j := i / _W
+	if j >= uint(len(x)) {
+		return 0
+	}
+	// 0 <= j < len(x)
+	return uint(x[j] >> (i % _W) & 1)
+}
+
+// sticky returns 1 if there's a 1 bit within the
+// i least significant bits, otherwise it returns 0.
+func (x nat) sticky(i uint) uint {
+	j := i / _W
+	if j >= uint(len(x)) {
+		if len(x) == 0 {
+			return 0
+		}
+		return 1
+	}
+	// 0 <= j < len(x)
+	for _, x := range x[:j] {
+		if x != 0 {
+			return 1
+		}
+	}
+	if x[j]<<(_W-i%_W) != 0 {
+		return 1
+	}
+	return 0
+}
+
+func (z nat) and(x, y nat) nat {
+	m := len(x)
+	n := len(y)
+	if m > n {
+		m = n
+	}
+	// m <= n
+
+	z = z.make(m)
+	for i := 0; i < m; i++ {
+		z[i] = x[i] & y[i]
+	}
+
+	return z.norm()
+}
+
+func (z nat) andNot(x, y nat) nat {
+	m := len(x)
+	n := len(y)
+	if n > m {
+		n = m
+	}
+	// m >= n
+
+	z = z.make(m)
+	for i := 0; i < n; i++ {
+		z[i] = x[i] &^ y[i]
+	}
+	copy(z[n:m], x[n:m])
+
+	return z.norm()
+}
+
+func (z nat) or(x, y nat) nat {
+	m := len(x)
+	n := len(y)
+	s := x
+	if m < n {
+		n, m = m, n
+		s = y
+	}
+	// m >= n
+
+	z = z.make(m)
+	for i := 0; i < n; i++ {
+		z[i] = x[i] | y[i]
+	}
+	copy(z[n:m], s[n:m])
+
+	return z.norm()
+}
+
+func (z nat) xor(x, y nat) nat {
+	m := len(x)
+	n := len(y)
+	s := x
+	if m < n {
+		n, m = m, n
+		s = y
+	}
+	// m >= n
+
+	z = z.make(m)
+	for i := 0; i < n; i++ {
+		z[i] = x[i] ^ y[i]
+	}
+	copy(z[n:m], s[n:m])
+
+	return z.norm()
+}
+
+// random creates a random integer in [0..limit), using the space in z if
+// possible. n is the bit length of limit.
+func (z nat) random(rand *rand.Rand, limit nat, n int) nat {
+	if alias(z, limit) {
+		z = nil // z is an alias for limit - cannot reuse
+	}
+	z = z.make(len(limit))
+
+	bitLengthOfMSW := uint(n % _W)
+	if bitLengthOfMSW == 0 {
+		bitLengthOfMSW = _W
+	}
+	mask := Word((1 << bitLengthOfMSW) - 1)
+
+	for {
+		switch _W {
+		case 32:
+			for i := range z {
+				z[i] = Word(rand.Uint32())
+			}
+		case 64:
+			for i := range z {
+				z[i] = Word(rand.Uint32()) | Word(rand.Uint32())<<32
+			}
+		default:
+			panic("unknown word size")
+		}
+		z[len(limit)-1] &= mask
+		if z.cmp(limit) < 0 {
+			break
+		}
+	}
+
+	return z.norm()
+}
+
+// If m != 0 (i.e., len(m) != 0), expNN sets z to x**y mod m;
+// otherwise it sets z to x**y. The result is the value of z.
+func (z nat) expNN(x, y, m nat) nat {
+	if alias(z, x) || alias(z, y) {
+		// We cannot allow in-place modification of x or y.
+		z = nil
+	}
+
+	// x**y mod 1 == 0
+	if len(m) == 1 && m[0] == 1 {
+		return z.setWord(0)
+	}
+	// m == 0 || m > 1
+
+	// x**0 == 1
+	if len(y) == 0 {
+		return z.setWord(1)
+	}
+	// y > 0
+
+	// x**1 mod m == x mod m
+	if len(y) == 1 && y[0] == 1 && len(m) != 0 {
+		_, z = nat(nil).div(z, x, m)
+		return z
+	}
+	// y > 1
+
+	if len(m) != 0 {
+		// We likely end up being as long as the modulus.
+		z = z.make(len(m))
+	}
+	z = z.set(x)
+
+	// If the base is non-trivial and the exponent is large, we use
+	// 4-bit, windowed exponentiation. This involves precomputing 14 values
+	// (x^2...x^15) but then reduces the number of multiply-reduces by a
+	// third. Even for a 32-bit exponent, this reduces the number of
+	// operations. Uses Montgomery method for odd moduli.
+	if x.cmp(natOne) > 0 && len(y) > 1 && len(m) > 0 {
+		if m[0]&1 == 1 {
+			return z.expNNMontgomery(x, y, m)
+		}
+		return z.expNNWindowed(x, y, m)
+	}
+
+	v := y[len(y)-1] // v > 0 because y is normalized and y > 0
+	shift := nlz(v) + 1
+	v <<= shift
+	var q nat
+
+	const mask = 1 << (_W - 1)
+
+	// We walk through the bits of the exponent one by one. Each time we
+	// see a bit, we square, thus doubling the power. If the bit is a one,
+	// we also multiply by x, thus adding one to the power.
+
+	w := _W - int(shift)
+	// zz and r are used to avoid allocating in mul and div as
+	// otherwise the arguments would alias.
+	var zz, r nat
+	for j := 0; j < w; j++ {
+		zz = zz.sqr(z)
+		zz, z = z, zz
+
+		if v&mask != 0 {
+			zz = zz.mul(z, x)
+			zz, z = z, zz
+		}
+
+		if len(m) != 0 {
+			zz, r = zz.div(r, z, m)
+			zz, r, q, z = q, z, zz, r
+		}
+
+		v <<= 1
+	}
+
+	for i := len(y) - 2; i >= 0; i-- {
+		v = y[i]
+
+		for j := 0; j < _W; j++ {
+			zz = zz.sqr(z)
+			zz, z = z, zz
+
+			if v&mask != 0 {
+				zz = zz.mul(z, x)
+				zz, z = z, zz
+			}
+
+			if len(m) != 0 {
+				zz, r = zz.div(r, z, m)
+				zz, r, q, z = q, z, zz, r
+			}
+
+			v <<= 1
+		}
+	}
+
+	return z.norm()
+}
+
+// expNNWindowed calculates x**y mod m using a fixed, 4-bit window.
+func (z nat) expNNWindowed(x, y, m nat) nat {
+	// zz and r are used to avoid allocating in mul and div as otherwise
+	// the arguments would alias.
+	var zz, r nat
+
+	const n = 4
+	// powers[i] contains x^i.
+	var powers [1 << n]nat
+	powers[0] = natOne
+	powers[1] = x
+	for i := 2; i < 1<<n; i += 2 {
+		p2, p, p1 := &powers[i/2], &powers[i], &powers[i+1]
+		*p = p.sqr(*p2)
+		zz, r = zz.div(r, *p, m)
+		*p, r = r, *p
+		*p1 = p1.mul(*p, x)
+		zz, r = zz.div(r, *p1, m)
+		*p1, r = r, *p1
+	}
+
+	z = z.setWord(1)
+
+	for i := len(y) - 1; i >= 0; i-- {
+		yi := y[i]
+		for j := 0; j < _W; j += n {
+			if i != len(y)-1 || j != 0 {
+				// Unrolled loop for significant performance
+				// gain. Use go test -bench=".*" in crypto/rsa
+				// to check performance before making changes.
+				zz = zz.sqr(z)
+				zz, z = z, zz
+				zz, r = zz.div(r, z, m)
+				z, r = r, z
+
+				zz = zz.sqr(z)
+				zz, z = z, zz
+				zz, r = zz.div(r, z, m)
+				z, r = r, z
+
+				zz = zz.sqr(z)
+				zz, z = z, zz
+				zz, r = zz.div(r, z, m)
+				z, r = r, z
+
+				zz = zz.sqr(z)
+				zz, z = z, zz
+				zz, r = zz.div(r, z, m)
+				z, r = r, z
+			}
+
+			zz = zz.mul(z, powers[yi>>(_W-n)])
+			zz, z = z, zz
+			zz, r = zz.div(r, z, m)
+			z, r = r, z
+
+			yi <<= n
+		}
+	}
+
+	return z.norm()
+}
+
+// expNNMontgomery calculates x**y mod m using a fixed, 4-bit window.
+// Uses Montgomery representation.
+func (z nat) expNNMontgomery(x, y, m nat) nat {
+	numWords := len(m)
+
+	// We want the lengths of x and m to be equal.
+	// It is OK if x >= m as long as len(x) == len(m).
+	if len(x) > numWords {
+		_, x = nat(nil).div(nil, x, m)
+		// Note: now len(x) <= numWords, not guaranteed ==.
+	}
+	if len(x) < numWords {
+		rr := make(nat, numWords)
+		copy(rr, x)
+		x = rr
+	}
+
+	// Ideally the precomputations would be performed outside, and reused
+	// k0 = -m**-1 mod 2**_W. Algorithm from: Dumas, J.G. "On Newton–Raphson
+	// Iteration for Multiplicative Inverses Modulo Prime Powers".
+	k0 := 2 - m[0]
+	t := m[0] - 1
+	for i := 1; i < _W; i <<= 1 {
+		t *= t
+		k0 *= (t + 1)
+	}
+	k0 = -k0
+
+	// RR = 2**(2*_W*len(m)) mod m
+	RR := nat(nil).setWord(1)
+	zz := nat(nil).shl(RR, uint(2*numWords*_W))
+	_, RR = nat(nil).div(RR, zz, m)
+	if len(RR) < numWords {
+		zz = zz.make(numWords)
+		copy(zz, RR)
+		RR = zz
+	}
+	// one = 1, with equal length to that of m
+	one := make(nat, numWords)
+	one[0] = 1
+
+	const n = 4
+	// powers[i] contains x^i
+	var powers [1 << n]nat
+	powers[0] = powers[0].montgomery(one, RR, m, k0, numWords)
+	powers[1] = powers[1].montgomery(x, RR, m, k0, numWords)
+	for i := 2; i < 1<<n; i++ {
+		powers[i] = powers[i].montgomery(powers[i-1], powers[1], m, k0, numWords)
+	}
+
+	// initialize z = 1 (Montgomery 1)
+	z = z.make(numWords)
+	copy(z, powers[0])
+
+	zz = zz.make(numWords)
+
+	// same windowed exponent, but with Montgomery multiplications
+	for i := len(y) - 1; i >= 0; i-- {
+		yi := y[i]
+		for j := 0; j < _W; j += n {
+			if i != len(y)-1 || j != 0 {
+				zz = zz.montgomery(z, z, m, k0, numWords)
+				z = z.montgomery(zz, zz, m, k0, numWords)
+				zz = zz.montgomery(z, z, m, k0, numWords)
+				z = z.montgomery(zz, zz, m, k0, numWords)
+			}
+			zz = zz.montgomery(z, powers[yi>>(_W-n)], m, k0, numWords)
+			z, zz = zz, z
+			yi <<= n
+		}
+	}
+	// convert to regular number
+	zz = zz.montgomery(z, one, m, k0, numWords)
+
+	// One last reduction, just in case.
+	// See golang.org/issue/13907.
+	if zz.cmp(m) >= 0 {
+		// Common case is m has high bit set; in that case,
+		// since zz is the same length as m, there can be just
+		// one multiple of m to remove. Just subtract.
+		// We think that the subtract should be sufficient in general,
+		// so do that unconditionally, but double-check,
+		// in case our beliefs are wrong.
+		// The div is not expected to be reached.
+		zz = zz.sub(zz, m)
+		if zz.cmp(m) >= 0 {
+			_, zz = nat(nil).div(nil, zz, m)
+		}
+	}
+
+	return zz.norm()
+}
+
+// bytes writes the value of z into buf using big-endian encoding.
+// The value of z is encoded in the slice buf[i:]. If the value of z
+// cannot be represented in buf, bytes panics. The number i of unused
+// bytes at the beginning of buf is returned as result.
+func (z nat) bytes(buf []byte) (i int) {
+	i = len(buf)
+	for _, d := range z {
+		for j := 0; j < _S; j++ {
+			i--
+			if i >= 0 {
+				buf[i] = byte(d)
+			} else if byte(d) != 0 {
+				panic("math/big: buffer too small to fit value")
+			}
+			d >>= 8
+		}
+	}
+
+	if i < 0 {
+		i = 0
+	}
+	for i < len(buf) && buf[i] == 0 {
+		i++
+	}
+
+	return
+}
+
+// bigEndianWord returns the contents of buf interpreted as a big-endian encoded Word value.
+func bigEndianWord(buf []byte) Word {
+	if _W == 64 {
+		return Word(binary.BigEndian.Uint64(buf))
+	}
+	return Word(binary.BigEndian.Uint32(buf))
+}
+
+// setBytes interprets buf as the bytes of a big-endian unsigned
+// integer, sets z to that value, and returns z.
+func (z nat) setBytes(buf []byte) nat {
+	z = z.make((len(buf) + _S - 1) / _S)
+
+	i := len(buf)
+	for k := 0; i >= _S; k++ {
+		z[k] = bigEndianWord(buf[i-_S : i])
+		i -= _S
+	}
+	if i > 0 {
+		var d Word
+		for s := uint(0); i > 0; s += 8 {
+			d |= Word(buf[i-1]) << s
+			i--
+		}
+		z[len(z)-1] = d
+	}
+
+	return z.norm()
+}
+
+// sqrt sets z = ⌊√x⌋
+func (z nat) sqrt(x nat) nat {
+	if x.cmp(natOne) <= 0 {
+		return z.set(x)
+	}
+	if alias(z, x) {
+		z = nil
+	}
+
+	// Start with value known to be too large and repeat "z = ⌊(z + ⌊x/z⌋)/2⌋" until it stops getting smaller.
+	// See Brent and Zimmermann, Modern Computer Arithmetic, Algorithm 1.13 (SqrtInt).
+	// https://members.loria.fr/PZimmermann/mca/pub226.html
+	// If x is one less than a perfect square, the sequence oscillates between the correct z and z+1;
+	// otherwise it converges to the correct z and stays there.
+	var z1, z2 nat
+	z1 = z
+	z1 = z1.setUint64(1)
+	z1 = z1.shl(z1, uint(x.bitLen()+1)/2) // must be ≥ √x
+	for n := 0; ; n++ {
+		z2, _ = z2.div(nil, x, z1)
+		z2 = z2.add(z2, z1)
+		z2 = z2.shr(z2, 1)
+		if z2.cmp(z1) >= 0 {
+			// z1 is answer.
+			// Figure out whether z1 or z2 is currently aliased to z by looking at loop count.
+			if n&1 == 0 {
+				return z1
+			}
+			return z.set(z1)
+		}
+		z1, z2 = z2, z1
+	}
+}
diff --git a/contrib/go/_std_1.19/src/math/big/natconv.go b/contrib/go/_std_1.19/src/math/big/natconv.go
new file mode 100644
index 0000000000..21fdab53fd
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/big/natconv.go
@@ -0,0 +1,511 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements nat-to-string conversion functions.
+
+package big
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"math"
+	"math/bits"
+	"sync"
+)
+
+const digits = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
+
+// Note: MaxBase = len(digits), but it must remain an untyped rune constant
+//       for API compatibility.
+
+// MaxBase is the largest number base accepted for string conversions.
+const MaxBase = 10 + ('z' - 'a' + 1) + ('Z' - 'A' + 1)
+const maxBaseSmall = 10 + ('z' - 'a' + 1)
+
+// maxPow returns (b**n, n) such that b**n is the largest power b**n <= _M.
+// For instance maxPow(10) == (1e19, 19) for 19 decimal digits in a 64bit Word.
+// In other words, at most n digits in base b fit into a Word.
+// TODO(gri) replace this with a table, generated at build time.
+func maxPow(b Word) (p Word, n int) {
+	p, n = b, 1 // assuming b <= _M
+	for max := _M / b; p <= max; {
+		// p == b**n && p <= max
+		p *= b
+		n++
+	}
+	// p == b**n && p <= _M
+	return
+}
+
+// pow returns x**n for n > 0, and 1 otherwise.
+func pow(x Word, n int) (p Word) {
+	// n == sum of bi * 2**i, for 0 <= i < imax, and bi is 0 or 1
+	// thus x**n == product of x**(2**i) for all i where bi == 1
+	// (Russian Peasant Method for exponentiation)
+	p = 1
+	for n > 0 {
+		if n&1 != 0 {
+			p *= x
+		}
+		x *= x
+		n >>= 1
+	}
+	return
+}
+
+// scan errors
+var (
+	errNoDigits = errors.New("number has no digits")
+	errInvalSep = errors.New("'_' must separate successive digits")
+)
+
+// scan scans the number corresponding to the longest possible prefix
+// from r representing an unsigned number in a given conversion base.
+// scan returns the corresponding natural number res, the actual base b,
+// a digit count, and a read or syntax error err, if any.
+//
+// For base 0, an underscore character “_” may appear between a base
+// prefix and an adjacent digit, and between successive digits; such
+// underscores do not change the value of the number, or the returned
+// digit count. Incorrect placement of underscores is reported as an
+// error if there are no other errors. If base != 0, underscores are
+// not recognized and thus terminate scanning like any other character
+// that is not a valid radix point or digit.
+//
+//	number    = mantissa | prefix pmantissa .
+//	prefix    = "0" [ "b" | "B" | "o" | "O" | "x" | "X" ] .
+//	mantissa  = digits "." [ digits ] | digits | "." digits .
+//	pmantissa = [ "_" ] digits "." [ digits ] | [ "_" ] digits | "." digits .
+//	digits    = digit { [ "_" ] digit } .
+//	digit     = "0" ... "9" | "a" ... "z" | "A" ... "Z" .
+//
+// Unless fracOk is set, the base argument must be 0 or a value between
+// 2 and MaxBase. If fracOk is set, the base argument must be one of
+// 0, 2, 8, 10, or 16. Providing an invalid base argument leads to a run-
+// time panic.
+//
+// For base 0, the number prefix determines the actual base: A prefix of
+// “0b” or “0B” selects base 2, “0o” or “0O” selects base 8, and
+// “0x” or “0X” selects base 16. If fracOk is false, a “0” prefix
+// (immediately followed by digits) selects base 8 as well. Otherwise,
+// the selected base is 10 and no prefix is accepted.
+//
+// If fracOk is set, a period followed by a fractional part is permitted.
+// The result value is computed as if there were no period present; and
+// the count value is used to determine the fractional part.
+//
+// For bases <= 36, lower and upper case letters are considered the same:
+// The letters 'a' to 'z' and 'A' to 'Z' represent digit values 10 to 35.
+// For bases > 36, the upper case letters 'A' to 'Z' represent the digit
+// values 36 to 61.
+//
+// A result digit count > 0 corresponds to the number of (non-prefix) digits
+// parsed. A digit count <= 0 indicates the presence of a period (if fracOk
+// is set, only), and -count is the number of fractional digits found.
+// In this case, the actual value of the scanned number is res * b**count.
+func (z nat) scan(r io.ByteScanner, base int, fracOk bool) (res nat, b, count int, err error) {
+	// reject invalid bases
+	baseOk := base == 0 ||
+		!fracOk && 2 <= base && base <= MaxBase ||
+		fracOk && (base == 2 || base == 8 || base == 10 || base == 16)
+	if !baseOk {
+		panic(fmt.Sprintf("invalid number base %d", base))
+	}
+
+	// prev encodes the previously seen char: it is one
+	// of '_', '0' (a digit), or '.' (anything else). A
+	// valid separator '_' may only occur after a digit
+	// and if base == 0.
+	prev := '.'
+	invalSep := false
+
+	// one char look-ahead
+	ch, err := r.ReadByte()
+
+	// determine actual base
+	b, prefix := base, 0
+	if base == 0 {
+		// actual base is 10 unless there's a base prefix
+		b = 10
+		if err == nil && ch == '0' {
+			prev = '0'
+			count = 1
+			ch, err = r.ReadByte()
+			if err == nil {
+				// possibly one of 0b, 0B, 0o, 0O, 0x, 0X
+				switch ch {
+				case 'b', 'B':
+					b, prefix = 2, 'b'
+				case 'o', 'O':
+					b, prefix = 8, 'o'
+				case 'x', 'X':
+					b, prefix = 16, 'x'
+				default:
+					if !fracOk {
+						b, prefix = 8, '0'
+					}
+				}
+				if prefix != 0 {
+					count = 0 // prefix is not counted
+					if prefix != '0' {
+						ch, err = r.ReadByte()
+					}
+				}
+			}
+		}
+	}
+
+	// convert string
+	// Algorithm: Collect digits in groups of at most n digits in di
+	// and then use mulAddWW for every such group to add them to the
+	// result.
+	z = z[:0]
+	b1 := Word(b)
+	bn, n := maxPow(b1) // at most n digits in base b1 fit into Word
+	di := Word(0)       // 0 <= di < b1**i < bn
+	i := 0              // 0 <= i < n
+	dp := -1            // position of decimal point
+	for err == nil {
+		if ch == '.' && fracOk {
+			fracOk = false
+			if prev == '_' {
+				invalSep = true
+			}
+			prev = '.'
+			dp = count
+		} else if ch == '_' && base == 0 {
+			if prev != '0' {
+				invalSep = true
+			}
+			prev = '_'
+		} else {
+			// convert rune into digit value d1
+			var d1 Word
+			switch {
+			case '0' <= ch && ch <= '9':
+				d1 = Word(ch - '0')
+			case 'a' <= ch && ch <= 'z':
+				d1 = Word(ch - 'a' + 10)
+			case 'A' <= ch && ch <= 'Z':
+				if b <= maxBaseSmall {
+					d1 = Word(ch - 'A' + 10)
+				} else {
+					d1 = Word(ch - 'A' + maxBaseSmall)
+				}
+			default:
+				d1 = MaxBase + 1
+			}
+			if d1 >= b1 {
+				r.UnreadByte() // ch does not belong to number anymore
+				break
+			}
+			prev = '0'
+			count++
+
+			// collect d1 in di
+			di = di*b1 + d1
+			i++
+
+			// if di is "full", add it to the result
+			if i == n {
+				z = z.mulAddWW(z, bn, di)
+				di = 0
+				i = 0
+			}
+		}
+
+		ch, err = r.ReadByte()
+	}
+
+	if err == io.EOF {
+		err = nil
+	}
+
+	// other errors take precedence over invalid separators
+	if err == nil && (invalSep || prev == '_') {
+		err = errInvalSep
+	}
+
+	if count == 0 {
+		// no digits found
+		if prefix == '0' {
+			// there was only the octal prefix 0 (possibly followed by separators and digits > 7);
+			// interpret as decimal 0
+			return z[:0], 10, 1, err
+		}
+		err = errNoDigits // fall through; result will be 0
+	}
+
+	// add remaining digits to result
+	if i > 0 {
+		z = z.mulAddWW(z, pow(b1, i), di)
+	}
+	res = z.norm()
+
+	// adjust count for fraction, if any
+	if dp >= 0 {
+		// 0 <= dp <= count
+		count = dp - count
+	}
+
+	return
+}
+
+// utoa converts x to an ASCII representation in the given base;
+// base must be between 2 and MaxBase, inclusive.
+func (x nat) utoa(base int) []byte {
+	return x.itoa(false, base)
+}
+
+// itoa is like utoa but it prepends a '-' if neg && x != 0.
+func (x nat) itoa(neg bool, base int) []byte {
+	if base < 2 || base > MaxBase {
+		panic("invalid base")
+	}
+
+	// x == 0
+	if len(x) == 0 {
+		return []byte("0")
+	}
+	// len(x) > 0
+
+	// allocate buffer for conversion
+	i := int(float64(x.bitLen())/math.Log2(float64(base))) + 1 // off by 1 at most
+	if neg {
+		i++
+	}
+	s := make([]byte, i)
+
+	// convert power of two and non power of two bases separately
+	if b := Word(base); b == b&-b {
+		// shift is base b digit size in bits
+		shift := uint(bits.TrailingZeros(uint(b))) // shift > 0 because b >= 2
+		mask := Word(1<<shift - 1)
+		w := x[0]         // current word
+		nbits := uint(_W) // number of unprocessed bits in w
+
+		// convert less-significant words (include leading zeros)
+		for k := 1; k < len(x); k++ {
+			// convert full digits
+			for nbits >= shift {
+				i--
+				s[i] = digits[w&mask]
+				w >>= shift
+				nbits -= shift
+			}
+
+			// convert any partial leading digit and advance to next word
+			if nbits == 0 {
+				// no partial digit remaining, just advance
+				w = x[k]
+				nbits = _W
+			} else {
+				// partial digit in current word w (== x[k-1]) and next word x[k]
+				w |= x[k] << nbits
+				i--
+				s[i] = digits[w&mask]
+
+				// advance
+				w = x[k] >> (shift - nbits)
+				nbits = _W - (shift - nbits)
+			}
+		}
+
+		// convert digits of most-significant word w (omit leading zeros)
+		for w != 0 {
+			i--
+			s[i] = digits[w&mask]
+			w >>= shift
+		}
+
+	} else {
+		bb, ndigits := maxPow(b)
+
+		// construct table of successive squares of bb*leafSize to use in subdivisions
+		// result (table != nil) <=> (len(x) > leafSize > 0)
+		table := divisors(len(x), b, ndigits, bb)
+
+		// preserve x, create local copy for use by convertWords
+		q := nat(nil).set(x)
+
+		// convert q to string s in base b
+		q.convertWords(s, b, ndigits, bb, table)
+
+		// strip leading zeros
+		// (x != 0; thus s must contain at least one non-zero digit
+		// and the loop will terminate)
+		i = 0
+		for s[i] == '0' {
+			i++
+		}
+	}
+
+	if neg {
+		i--
+		s[i] = '-'
+	}
+
+	return s[i:]
+}
+
+// Convert words of q to base b digits in s. If q is large, it is recursively "split in half"
+// by nat/nat division using tabulated divisors. Otherwise, it is converted iteratively using
+// repeated nat/Word division.
+//
+// The iterative method processes n Words by n divW() calls, each of which visits every Word in the
+// incrementally shortened q for a total of n + (n-1) + (n-2) ... + 2 + 1, or n(n+1)/2 divW()'s.
+// Recursive conversion divides q by its approximate square root, yielding two parts, each half
+// the size of q. Using the iterative method on both halves means 2 * (n/2)(n/2 + 1)/2 divW()'s
+// plus the expensive long div(). Asymptotically, the ratio is favorable at 1/2 the divW()'s, and
+// is made better by splitting the subblocks recursively. Best is to split blocks until one more
+// split would take longer (because of the nat/nat div()) than the twice as many divW()'s of the
+// iterative approach. This threshold is represented by leafSize. Benchmarking of leafSize in the
+// range 2..64 shows that values of 8 and 16 work well, with a 4x speedup at medium lengths and
+// ~30x for 20000 digits. Use nat_test.go's BenchmarkLeafSize tests to optimize leafSize for
+// specific hardware.
+func (q nat) convertWords(s []byte, b Word, ndigits int, bb Word, table []divisor) {
+	// split larger blocks recursively
+	if table != nil {
+		// len(q) > leafSize > 0
+		var r nat
+		index := len(table) - 1
+		for len(q) > leafSize {
+			// find divisor close to sqrt(q) if possible, but in any case < q
+			maxLength := q.bitLen()     // ~= log2 q, or at of least largest possible q of this bit length
+			minLength := maxLength >> 1 // ~= log2 sqrt(q)
+			for index > 0 && table[index-1].nbits > minLength {
+				index-- // desired
+			}
+			if table[index].nbits >= maxLength && table[index].bbb.cmp(q) >= 0 {
+				index--
+				if index < 0 {
+					panic("internal inconsistency")
+				}
+			}
+
+			// split q into the two digit number (q'*bbb + r) to form independent subblocks
+			q, r = q.div(r, q, table[index].bbb)
+
+			// convert subblocks and collect results in s[:h] and s[h:]
+			h := len(s) - table[index].ndigits
+			r.convertWords(s[h:], b, ndigits, bb, table[0:index])
+			s = s[:h] // == q.convertWords(s, b, ndigits, bb, table[0:index+1])
+		}
+	}
+
+	// having split any large blocks now process the remaining (small) block iteratively
+	i := len(s)
+	var r Word
+	if b == 10 {
+		// hard-coding for 10 here speeds this up by 1.25x (allows for / and % by constants)
+		for len(q) > 0 {
+			// extract least significant, base bb "digit"
+			q, r = q.divW(q, bb)
+			for j := 0; j < ndigits && i > 0; j++ {
+				i--
+				// avoid % computation since r%10 == r - int(r/10)*10;
+				// this appears to be faster for BenchmarkString10000Base10
+				// and smaller strings (but a bit slower for larger ones)
+				t := r / 10
+				s[i] = '0' + byte(r-t*10)
+				r = t
+			}
+		}
+	} else {
+		for len(q) > 0 {
+			// extract least significant, base bb "digit"
+			q, r = q.divW(q, bb)
+			for j := 0; j < ndigits && i > 0; j++ {
+				i--
+				s[i] = digits[r%b]
+				r /= b
+			}
+		}
+	}
+
+	// prepend high-order zeros
+	for i > 0 { // while need more leading zeros
+		i--
+		s[i] = '0'
+	}
+}
+
+// Split blocks greater than leafSize Words (or set to 0 to disable recursive conversion)
+// Benchmark and configure leafSize using: go test -bench="Leaf"
+//
+//	8 and 16 effective on 3.0 GHz Xeon "Clovertown" CPU (128 byte cache lines)
+//	8 and 16 effective on 2.66 GHz Core 2 Duo "Penryn" CPU
+var leafSize int = 8 // number of Word-size binary values treat as a monolithic block
+
+type divisor struct {
+	bbb     nat // divisor
+	nbits   int // bit length of divisor (discounting leading zeros) ~= log2(bbb)
+	ndigits int // digit length of divisor in terms of output base digits
+}
+
+var cacheBase10 struct {
+	sync.Mutex
+	table [64]divisor // cached divisors for base 10
+}
+
+// expWW computes x**y
+func (z nat) expWW(x, y Word) nat {
+	return z.expNN(nat(nil).setWord(x), nat(nil).setWord(y), nil)
+}
+
+// construct table of powers of bb*leafSize to use in subdivisions
+func divisors(m int, b Word, ndigits int, bb Word) []divisor {
+	// only compute table when recursive conversion is enabled and x is large
+	if leafSize == 0 || m <= leafSize {
+		return nil
+	}
+
+	// determine k where (bb**leafSize)**(2**k) >= sqrt(x)
+	k := 1
+	for words := leafSize; words < m>>1 && k < len(cacheBase10.table); words <<= 1 {
+		k++
+	}
+
+	// reuse and extend existing table of divisors or create new table as appropriate
+	var table []divisor // for b == 10, table overlaps with cacheBase10.table
+	if b == 10 {
+		cacheBase10.Lock()
+		table = cacheBase10.table[0:k] // reuse old table for this conversion
+	} else {
+		table = make([]divisor, k) // create new table for this conversion
+	}
+
+	// extend table
+	if table[k-1].ndigits == 0 {
+		// add new entries as needed
+		var larger nat
+		for i := 0; i < k; i++ {
+			if table[i].ndigits == 0 {
+				if i == 0 {
+					table[0].bbb = nat(nil).expWW(bb, Word(leafSize))
+					table[0].ndigits = ndigits * leafSize
+				} else {
+					table[i].bbb = nat(nil).sqr(table[i-1].bbb)
+					table[i].ndigits = 2 * table[i-1].ndigits
+				}
+
+				// optimization: exploit aggregated extra bits in macro blocks
+				larger = nat(nil).set(table[i].bbb)
+				for mulAddVWW(larger, larger, b, 0) == 0 {
+					table[i].bbb = table[i].bbb.set(larger)
+					table[i].ndigits++
+				}
+
+				table[i].nbits = table[i].bbb.bitLen()
+			}
+		}
+	}
+
+	if b == 10 {
+		cacheBase10.Unlock()
+	}
+
+	return table
+}
diff --git a/contrib/go/_std_1.18/src/math/big/natdiv.go b/contrib/go/_std_1.19/src/math/big/natdiv.go
index 882bb6d3ba..882bb6d3ba 100644
--- a/contrib/go/_std_1.18/src/math/big/natdiv.go
+++ b/contrib/go/_std_1.19/src/math/big/natdiv.go
diff --git a/contrib/go/_std_1.18/src/math/big/prime.go b/contrib/go/_std_1.19/src/math/big/prime.go
index d9a5f1ec96..d9a5f1ec96 100644
--- a/contrib/go/_std_1.18/src/math/big/prime.go
+++ b/contrib/go/_std_1.19/src/math/big/prime.go
diff --git a/contrib/go/_std_1.19/src/math/big/rat.go b/contrib/go/_std_1.19/src/math/big/rat.go
new file mode 100644
index 0000000000..700a643265
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/big/rat.go
@@ -0,0 +1,542 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements multi-precision rational numbers.
+
+package big
+
+import (
+	"fmt"
+	"math"
+)
+
+// A Rat represents a quotient a/b of arbitrary precision.
+// The zero value for a Rat represents the value 0.
+//
+// Operations always take pointer arguments (*Rat) rather
+// than Rat values, and each unique Rat value requires
+// its own unique *Rat pointer. To "copy" a Rat value,
+// an existing (or newly allocated) Rat must be set to
+// a new value using the Rat.Set method; shallow copies
+// of Rats are not supported and may lead to errors.
+type Rat struct {
+	// To make zero values for Rat work w/o initialization,
+	// a zero value of b (len(b) == 0) acts like b == 1. At
+	// the earliest opportunity (when an assignment to the Rat
+	// is made), such uninitialized denominators are set to 1.
+	// a.neg determines the sign of the Rat, b.neg is ignored.
+	a, b Int
+}
+
+// NewRat creates a new Rat with numerator a and denominator b.
+func NewRat(a, b int64) *Rat {
+	return new(Rat).SetFrac64(a, b)
+}
+
+// SetFloat64 sets z to exactly f and returns z.
+// If f is not finite, SetFloat returns nil.
+func (z *Rat) SetFloat64(f float64) *Rat {
+	const expMask = 1<<11 - 1
+	bits := math.Float64bits(f)
+	mantissa := bits & (1<<52 - 1)
+	exp := int((bits >> 52) & expMask)
+	switch exp {
+	case expMask: // non-finite
+		return nil
+	case 0: // denormal
+		exp -= 1022
+	default: // normal
+		mantissa |= 1 << 52
+		exp -= 1023
+	}
+
+	shift := 52 - exp
+
+	// Optimization (?): partially pre-normalise.
+	for mantissa&1 == 0 && shift > 0 {
+		mantissa >>= 1
+		shift--
+	}
+
+	z.a.SetUint64(mantissa)
+	z.a.neg = f < 0
+	z.b.Set(intOne)
+	if shift > 0 {
+		z.b.Lsh(&z.b, uint(shift))
+	} else {
+		z.a.Lsh(&z.a, uint(-shift))
+	}
+	return z.norm()
+}
+
+// quotToFloat32 returns the non-negative float32 value
+// nearest to the quotient a/b, using round-to-even in
+// halfway cases. It does not mutate its arguments.
+// Preconditions: b is non-zero; a and b have no common factors.
+func quotToFloat32(a, b nat) (f float32, exact bool) {
+	const (
+		// float size in bits
+		Fsize = 32
+
+		// mantissa
+		Msize  = 23
+		Msize1 = Msize + 1 // incl. implicit 1
+		Msize2 = Msize1 + 1
+
+		// exponent
+		Esize = Fsize - Msize1
+		Ebias = 1<<(Esize-1) - 1
+		Emin  = 1 - Ebias
+		Emax  = Ebias
+	)
+
+	// TODO(adonovan): specialize common degenerate cases: 1.0, integers.
+	alen := a.bitLen()
+	if alen == 0 {
+		return 0, true
+	}
+	blen := b.bitLen()
+	if blen == 0 {
+		panic("division by zero")
+	}
+
+	// 1. Left-shift A or B such that quotient A/B is in [1<<Msize1, 1<<(Msize2+1)
+	// (Msize2 bits if A < B when they are left-aligned, Msize2+1 bits if A >= B).
+	// This is 2 or 3 more than the float32 mantissa field width of Msize:
+	// - the optional extra bit is shifted away in step 3 below.
+	// - the high-order 1 is omitted in "normal" representation;
+	// - the low-order 1 will be used during rounding then discarded.
+	exp := alen - blen
+	var a2, b2 nat
+	a2 = a2.set(a)
+	b2 = b2.set(b)
+	if shift := Msize2 - exp; shift > 0 {
+		a2 = a2.shl(a2, uint(shift))
+	} else if shift < 0 {
+		b2 = b2.shl(b2, uint(-shift))
+	}
+
+	// 2. Compute quotient and remainder (q, r).  NB: due to the
+	// extra shift, the low-order bit of q is logically the
+	// high-order bit of r.
+	var q nat
+	q, r := q.div(a2, a2, b2) // (recycle a2)
+	mantissa := low32(q)
+	haveRem := len(r) > 0 // mantissa&1 && !haveRem => remainder is exactly half
+
+	// 3. If quotient didn't fit in Msize2 bits, redo division by b2<<1
+	// (in effect---we accomplish this incrementally).
+	if mantissa>>Msize2 == 1 {
+		if mantissa&1 == 1 {
+			haveRem = true
+		}
+		mantissa >>= 1
+		exp++
+	}
+	if mantissa>>Msize1 != 1 {
+		panic(fmt.Sprintf("expected exactly %d bits of result", Msize2))
+	}
+
+	// 4. Rounding.
+	if Emin-Msize <= exp && exp <= Emin {
+		// Denormal case; lose 'shift' bits of precision.
+		shift := uint(Emin - (exp - 1)) // [1..Esize1)
+		lostbits := mantissa & (1<<shift - 1)
+		haveRem = haveRem || lostbits != 0
+		mantissa >>= shift
+		exp = 2 - Ebias // == exp + shift
+	}
+	// Round q using round-half-to-even.
+	exact = !haveRem
+	if mantissa&1 != 0 {
+		exact = false
+		if haveRem || mantissa&2 != 0 {
+			if mantissa++; mantissa >= 1<<Msize2 {
+				// Complete rollover 11...1 => 100...0, so shift is safe
+				mantissa >>= 1
+				exp++
+			}
+		}
+	}
+	mantissa >>= 1 // discard rounding bit.  Mantissa now scaled by 1<<Msize1.
+
+	f = float32(math.Ldexp(float64(mantissa), exp-Msize1))
+	if math.IsInf(float64(f), 0) {
+		exact = false
+	}
+	return
+}
+
+// quotToFloat64 returns the non-negative float64 value
+// nearest to the quotient a/b, using round-to-even in
+// halfway cases. It does not mutate its arguments.
+// Preconditions: b is non-zero; a and b have no common factors.
+func quotToFloat64(a, b nat) (f float64, exact bool) {
+	const (
+		// float size in bits
+		Fsize = 64
+
+		// mantissa
+		Msize  = 52
+		Msize1 = Msize + 1 // incl. implicit 1
+		Msize2 = Msize1 + 1
+
+		// exponent
+		Esize = Fsize - Msize1
+		Ebias = 1<<(Esize-1) - 1
+		Emin  = 1 - Ebias
+		Emax  = Ebias
+	)
+
+	// TODO(adonovan): specialize common degenerate cases: 1.0, integers.
+	alen := a.bitLen()
+	if alen == 0 {
+		return 0, true
+	}
+	blen := b.bitLen()
+	if blen == 0 {
+		panic("division by zero")
+	}
+
+	// 1. Left-shift A or B such that quotient A/B is in [1<<Msize1, 1<<(Msize2+1)
+	// (Msize2 bits if A < B when they are left-aligned, Msize2+1 bits if A >= B).
+	// This is 2 or 3 more than the float64 mantissa field width of Msize:
+	// - the optional extra bit is shifted away in step 3 below.
+	// - the high-order 1 is omitted in "normal" representation;
+	// - the low-order 1 will be used during rounding then discarded.
+	exp := alen - blen
+	var a2, b2 nat
+	a2 = a2.set(a)
+	b2 = b2.set(b)
+	if shift := Msize2 - exp; shift > 0 {
+		a2 = a2.shl(a2, uint(shift))
+	} else if shift < 0 {
+		b2 = b2.shl(b2, uint(-shift))
+	}
+
+	// 2. Compute quotient and remainder (q, r).  NB: due to the
+	// extra shift, the low-order bit of q is logically the
+	// high-order bit of r.
+	var q nat
+	q, r := q.div(a2, a2, b2) // (recycle a2)
+	mantissa := low64(q)
+	haveRem := len(r) > 0 // mantissa&1 && !haveRem => remainder is exactly half
+
+	// 3. If quotient didn't fit in Msize2 bits, redo division by b2<<1
+	// (in effect---we accomplish this incrementally).
+	if mantissa>>Msize2 == 1 {
+		if mantissa&1 == 1 {
+			haveRem = true
+		}
+		mantissa >>= 1
+		exp++
+	}
+	if mantissa>>Msize1 != 1 {
+		panic(fmt.Sprintf("expected exactly %d bits of result", Msize2))
+	}
+
+	// 4. Rounding.
+	if Emin-Msize <= exp && exp <= Emin {
+		// Denormal case; lose 'shift' bits of precision.
+		shift := uint(Emin - (exp - 1)) // [1..Esize1)
+		lostbits := mantissa & (1<<shift - 1)
+		haveRem = haveRem || lostbits != 0
+		mantissa >>= shift
+		exp = 2 - Ebias // == exp + shift
+	}
+	// Round q using round-half-to-even.
+	exact = !haveRem
+	if mantissa&1 != 0 {
+		exact = false
+		if haveRem || mantissa&2 != 0 {
+			if mantissa++; mantissa >= 1<<Msize2 {
+				// Complete rollover 11...1 => 100...0, so shift is safe
+				mantissa >>= 1
+				exp++
+			}
+		}
+	}
+	mantissa >>= 1 // discard rounding bit.  Mantissa now scaled by 1<<Msize1.
+
+	f = math.Ldexp(float64(mantissa), exp-Msize1)
+	if math.IsInf(f, 0) {
+		exact = false
+	}
+	return
+}
+
+// Float32 returns the nearest float32 value for x and a bool indicating
+// whether f represents x exactly. If the magnitude of x is too large to
+// be represented by a float32, f is an infinity and exact is false.
+// The sign of f always matches the sign of x, even if f == 0.
+func (x *Rat) Float32() (f float32, exact bool) {
+	b := x.b.abs
+	if len(b) == 0 {
+		b = natOne
+	}
+	f, exact = quotToFloat32(x.a.abs, b)
+	if x.a.neg {
+		f = -f
+	}
+	return
+}
+
+// Float64 returns the nearest float64 value for x and a bool indicating
+// whether f represents x exactly. If the magnitude of x is too large to
+// be represented by a float64, f is an infinity and exact is false.
+// The sign of f always matches the sign of x, even if f == 0.
+func (x *Rat) Float64() (f float64, exact bool) {
+	b := x.b.abs
+	if len(b) == 0 {
+		b = natOne
+	}
+	f, exact = quotToFloat64(x.a.abs, b)
+	if x.a.neg {
+		f = -f
+	}
+	return
+}
+
+// SetFrac sets z to a/b and returns z.
+// If b == 0, SetFrac panics.
+func (z *Rat) SetFrac(a, b *Int) *Rat {
+	z.a.neg = a.neg != b.neg
+	babs := b.abs
+	if len(babs) == 0 {
+		panic("division by zero")
+	}
+	if &z.a == b || alias(z.a.abs, babs) {
+		babs = nat(nil).set(babs) // make a copy
+	}
+	z.a.abs = z.a.abs.set(a.abs)
+	z.b.abs = z.b.abs.set(babs)
+	return z.norm()
+}
+
+// SetFrac64 sets z to a/b and returns z.
+// If b == 0, SetFrac64 panics.
+func (z *Rat) SetFrac64(a, b int64) *Rat {
+	if b == 0 {
+		panic("division by zero")
+	}
+	z.a.SetInt64(a)
+	if b < 0 {
+		b = -b
+		z.a.neg = !z.a.neg
+	}
+	z.b.abs = z.b.abs.setUint64(uint64(b))
+	return z.norm()
+}
+
+// SetInt sets z to x (by making a copy of x) and returns z.
+func (z *Rat) SetInt(x *Int) *Rat {
+	z.a.Set(x)
+	z.b.abs = z.b.abs.setWord(1)
+	return z
+}
+
+// SetInt64 sets z to x and returns z.
+func (z *Rat) SetInt64(x int64) *Rat {
+	z.a.SetInt64(x)
+	z.b.abs = z.b.abs.setWord(1)
+	return z
+}
+
+// SetUint64 sets z to x and returns z.
+func (z *Rat) SetUint64(x uint64) *Rat {
+	z.a.SetUint64(x)
+	z.b.abs = z.b.abs.setWord(1)
+	return z
+}
+
+// Set sets z to x (by making a copy of x) and returns z.
+func (z *Rat) Set(x *Rat) *Rat {
+	if z != x {
+		z.a.Set(&x.a)
+		z.b.Set(&x.b)
+	}
+	if len(z.b.abs) == 0 {
+		z.b.abs = z.b.abs.setWord(1)
+	}
+	return z
+}
+
+// Abs sets z to |x| (the absolute value of x) and returns z.
+func (z *Rat) Abs(x *Rat) *Rat {
+	z.Set(x)
+	z.a.neg = false
+	return z
+}
+
+// Neg sets z to -x and returns z.
+func (z *Rat) Neg(x *Rat) *Rat {
+	z.Set(x)
+	z.a.neg = len(z.a.abs) > 0 && !z.a.neg // 0 has no sign
+	return z
+}
+
+// Inv sets z to 1/x and returns z.
+// If x == 0, Inv panics.
+func (z *Rat) Inv(x *Rat) *Rat {
+	if len(x.a.abs) == 0 {
+		panic("division by zero")
+	}
+	z.Set(x)
+	z.a.abs, z.b.abs = z.b.abs, z.a.abs
+	return z
+}
+
+// Sign returns:
+//
+//	-1 if x <  0
+//	 0 if x == 0
+//	+1 if x >  0
+func (x *Rat) Sign() int {
+	return x.a.Sign()
+}
+
+// IsInt reports whether the denominator of x is 1.
+func (x *Rat) IsInt() bool {
+	return len(x.b.abs) == 0 || x.b.abs.cmp(natOne) == 0
+}
+
+// Num returns the numerator of x; it may be <= 0.
+// The result is a reference to x's numerator; it
+// may change if a new value is assigned to x, and vice versa.
+// The sign of the numerator corresponds to the sign of x.
+func (x *Rat) Num() *Int {
+	return &x.a
+}
+
+// Denom returns the denominator of x; it is always > 0.
+// The result is a reference to x's denominator, unless
+// x is an uninitialized (zero value) Rat, in which case
+// the result is a new Int of value 1. (To initialize x,
+// any operation that sets x will do, including x.Set(x).)
+// If the result is a reference to x's denominator it
+// may change if a new value is assigned to x, and vice versa.
+func (x *Rat) Denom() *Int {
+	// Note that x.b.neg is guaranteed false.
+	if len(x.b.abs) == 0 {
+		// Note: If this proves problematic, we could
+		//       panic instead and require the Rat to
+		//       be explicitly initialized.
+		return &Int{abs: nat{1}}
+	}
+	return &x.b
+}
+
+func (z *Rat) norm() *Rat {
+	switch {
+	case len(z.a.abs) == 0:
+		// z == 0; normalize sign and denominator
+		z.a.neg = false
+		fallthrough
+	case len(z.b.abs) == 0:
+		// z is integer; normalize denominator
+		z.b.abs = z.b.abs.setWord(1)
+	default:
+		// z is fraction; normalize numerator and denominator
+		neg := z.a.neg
+		z.a.neg = false
+		z.b.neg = false
+		if f := NewInt(0).lehmerGCD(nil, nil, &z.a, &z.b); f.Cmp(intOne) != 0 {
+			z.a.abs, _ = z.a.abs.div(nil, z.a.abs, f.abs)
+			z.b.abs, _ = z.b.abs.div(nil, z.b.abs, f.abs)
+		}
+		z.a.neg = neg
+	}
+	return z
+}
+
+// mulDenom sets z to the denominator product x*y (by taking into
+// account that 0 values for x or y must be interpreted as 1) and
+// returns z.
+func mulDenom(z, x, y nat) nat {
+	switch {
+	case len(x) == 0 && len(y) == 0:
+		return z.setWord(1)
+	case len(x) == 0:
+		return z.set(y)
+	case len(y) == 0:
+		return z.set(x)
+	}
+	return z.mul(x, y)
+}
+
+// scaleDenom sets z to the product x*f.
+// If f == 0 (zero value of denominator), z is set to (a copy of) x.
+func (z *Int) scaleDenom(x *Int, f nat) {
+	if len(f) == 0 {
+		z.Set(x)
+		return
+	}
+	z.abs = z.abs.mul(x.abs, f)
+	z.neg = x.neg
+}
+
+// Cmp compares x and y and returns:
+//
+//	-1 if x <  y
+//	 0 if x == y
+//	+1 if x >  y
+func (x *Rat) Cmp(y *Rat) int {
+	var a, b Int
+	a.scaleDenom(&x.a, y.b.abs)
+	b.scaleDenom(&y.a, x.b.abs)
+	return a.Cmp(&b)
+}
+
+// Add sets z to the sum x+y and returns z.
+func (z *Rat) Add(x, y *Rat) *Rat {
+	var a1, a2 Int
+	a1.scaleDenom(&x.a, y.b.abs)
+	a2.scaleDenom(&y.a, x.b.abs)
+	z.a.Add(&a1, &a2)
+	z.b.abs = mulDenom(z.b.abs, x.b.abs, y.b.abs)
+	return z.norm()
+}
+
+// Sub sets z to the difference x-y and returns z.
+func (z *Rat) Sub(x, y *Rat) *Rat {
+	var a1, a2 Int
+	a1.scaleDenom(&x.a, y.b.abs)
+	a2.scaleDenom(&y.a, x.b.abs)
+	z.a.Sub(&a1, &a2)
+	z.b.abs = mulDenom(z.b.abs, x.b.abs, y.b.abs)
+	return z.norm()
+}
+
+// Mul sets z to the product x*y and returns z.
+func (z *Rat) Mul(x, y *Rat) *Rat {
+	if x == y {
+		// a squared Rat is positive and can't be reduced (no need to call norm())
+		z.a.neg = false
+		z.a.abs = z.a.abs.sqr(x.a.abs)
+		if len(x.b.abs) == 0 {
+			z.b.abs = z.b.abs.setWord(1)
+		} else {
+			z.b.abs = z.b.abs.sqr(x.b.abs)
+		}
+		return z
+	}
+	z.a.Mul(&x.a, &y.a)
+	z.b.abs = mulDenom(z.b.abs, x.b.abs, y.b.abs)
+	return z.norm()
+}
+
+// Quo sets z to the quotient x/y and returns z.
+// If y == 0, Quo panics.
+func (z *Rat) Quo(x, y *Rat) *Rat {
+	if len(y.a.abs) == 0 {
+		panic("division by zero")
+	}
+	var a, b Int
+	a.scaleDenom(&x.a, y.b.abs)
+	b.scaleDenom(&y.a, x.b.abs)
+	z.a.abs = a.abs
+	z.b.abs = b.abs
+	z.a.neg = a.neg != b.neg
+	return z.norm()
+}
diff --git a/contrib/go/_std_1.19/src/math/big/ratconv.go b/contrib/go/_std_1.19/src/math/big/ratconv.go
new file mode 100644
index 0000000000..794a51d007
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/big/ratconv.go
@@ -0,0 +1,380 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements rat-to-string conversion functions.
+
+package big
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"strconv"
+	"strings"
+)
+
+func ratTok(ch rune) bool {
+	return strings.ContainsRune("+-/0123456789.eE", ch)
+}
+
+var ratZero Rat
+var _ fmt.Scanner = &ratZero // *Rat must implement fmt.Scanner
+
+// Scan is a support routine for fmt.Scanner. It accepts the formats
+// 'e', 'E', 'f', 'F', 'g', 'G', and 'v'. All formats are equivalent.
+func (z *Rat) Scan(s fmt.ScanState, ch rune) error {
+	tok, err := s.Token(true, ratTok)
+	if err != nil {
+		return err
+	}
+	if !strings.ContainsRune("efgEFGv", ch) {
+		return errors.New("Rat.Scan: invalid verb")
+	}
+	if _, ok := z.SetString(string(tok)); !ok {
+		return errors.New("Rat.Scan: invalid syntax")
+	}
+	return nil
+}
+
+// SetString sets z to the value of s and returns z and a boolean indicating
+// success. s can be given as a (possibly signed) fraction "a/b", or as a
+// floating-point number optionally followed by an exponent.
+// If a fraction is provided, both the dividend and the divisor may be a
+// decimal integer or independently use a prefix of “0b”, “0” or “0o”,
+// or “0x” (or their upper-case variants) to denote a binary, octal, or
+// hexadecimal integer, respectively. The divisor may not be signed.
+// If a floating-point number is provided, it may be in decimal form or
+// use any of the same prefixes as above but for “0” to denote a non-decimal
+// mantissa. A leading “0” is considered a decimal leading 0; it does not
+// indicate octal representation in this case.
+// An optional base-10 “e” or base-2 “p” (or their upper-case variants)
+// exponent may be provided as well, except for hexadecimal floats which
+// only accept an (optional) “p” exponent (because an “e” or “E” cannot
+// be distinguished from a mantissa digit). If the exponent's absolute value
+// is too large, the operation may fail.
+// The entire string, not just a prefix, must be valid for success. If the
+// operation failed, the value of z is undefined but the returned value is nil.
+func (z *Rat) SetString(s string) (*Rat, bool) {
+	if len(s) == 0 {
+		return nil, false
+	}
+	// len(s) > 0
+
+	// parse fraction a/b, if any
+	if sep := strings.Index(s, "/"); sep >= 0 {
+		if _, ok := z.a.SetString(s[:sep], 0); !ok {
+			return nil, false
+		}
+		r := strings.NewReader(s[sep+1:])
+		var err error
+		if z.b.abs, _, _, err = z.b.abs.scan(r, 0, false); err != nil {
+			return nil, false
+		}
+		// entire string must have been consumed
+		if _, err = r.ReadByte(); err != io.EOF {
+			return nil, false
+		}
+		if len(z.b.abs) == 0 {
+			return nil, false
+		}
+		return z.norm(), true
+	}
+
+	// parse floating-point number
+	r := strings.NewReader(s)
+
+	// sign
+	neg, err := scanSign(r)
+	if err != nil {
+		return nil, false
+	}
+
+	// mantissa
+	var base int
+	var fcount int // fractional digit count; valid if <= 0
+	z.a.abs, base, fcount, err = z.a.abs.scan(r, 0, true)
+	if err != nil {
+		return nil, false
+	}
+
+	// exponent
+	var exp int64
+	var ebase int
+	exp, ebase, err = scanExponent(r, true, true)
+	if err != nil {
+		return nil, false
+	}
+
+	// there should be no unread characters left
+	if _, err = r.ReadByte(); err != io.EOF {
+		return nil, false
+	}
+
+	// special-case 0 (see also issue #16176)
+	if len(z.a.abs) == 0 {
+		return z.norm(), true
+	}
+	// len(z.a.abs) > 0
+
+	// The mantissa may have a radix point (fcount <= 0) and there
+	// may be a nonzero exponent exp. The radix point amounts to a
+	// division by base**(-fcount), which equals a multiplication by
+	// base**fcount. An exponent means multiplication by ebase**exp.
+	// Multiplications are commutative, so we can apply them in any
+	// order. We only have powers of 2 and 10, and we split powers
+	// of 10 into the product of the same powers of 2 and 5. This
+	// may reduce the size of shift/multiplication factors or
+	// divisors required to create the final fraction, depending
+	// on the actual floating-point value.
+
+	// determine binary or decimal exponent contribution of radix point
+	var exp2, exp5 int64
+	if fcount < 0 {
+		// The mantissa has a radix point ddd.dddd; and
+		// -fcount is the number of digits to the right
+		// of '.'. Adjust relevant exponent accordingly.
+		d := int64(fcount)
+		switch base {
+		case 10:
+			exp5 = d
+			fallthrough // 10**e == 5**e * 2**e
+		case 2:
+			exp2 = d
+		case 8:
+			exp2 = d * 3 // octal digits are 3 bits each
+		case 16:
+			exp2 = d * 4 // hexadecimal digits are 4 bits each
+		default:
+			panic("unexpected mantissa base")
+		}
+		// fcount consumed - not needed anymore
+	}
+
+	// take actual exponent into account
+	switch ebase {
+	case 10:
+		exp5 += exp
+		fallthrough // see fallthrough above
+	case 2:
+		exp2 += exp
+	default:
+		panic("unexpected exponent base")
+	}
+	// exp consumed - not needed anymore
+
+	// apply exp5 contributions
+	// (start with exp5 so the numbers to multiply are smaller)
+	if exp5 != 0 {
+		n := exp5
+		if n < 0 {
+			n = -n
+			if n < 0 {
+				// This can occur if -n overflows. -(-1 << 63) would become
+				// -1 << 63, which is still negative.
+				return nil, false
+			}
+		}
+		if n > 1e6 {
+			return nil, false // avoid excessively large exponents
+		}
+		pow5 := z.b.abs.expNN(natFive, nat(nil).setWord(Word(n)), nil) // use underlying array of z.b.abs
+		if exp5 > 0 {
+			z.a.abs = z.a.abs.mul(z.a.abs, pow5)
+			z.b.abs = z.b.abs.setWord(1)
+		} else {
+			z.b.abs = pow5
+		}
+	} else {
+		z.b.abs = z.b.abs.setWord(1)
+	}
+
+	// apply exp2 contributions
+	if exp2 < -1e7 || exp2 > 1e7 {
+		return nil, false // avoid excessively large exponents
+	}
+	if exp2 > 0 {
+		z.a.abs = z.a.abs.shl(z.a.abs, uint(exp2))
+	} else if exp2 < 0 {
+		z.b.abs = z.b.abs.shl(z.b.abs, uint(-exp2))
+	}
+
+	z.a.neg = neg && len(z.a.abs) > 0 // 0 has no sign
+
+	return z.norm(), true
+}
+
+// scanExponent scans the longest possible prefix of r representing a base 10
+// (“e”, “E”) or a base 2 (“p”, “P”) exponent, if any. It returns the
+// exponent, the exponent base (10 or 2), or a read or syntax error, if any.
+//
+// If sepOk is set, an underscore character “_” may appear between successive
+// exponent digits; such underscores do not change the value of the exponent.
+// Incorrect placement of underscores is reported as an error if there are no
+// other errors. If sepOk is not set, underscores are not recognized and thus
+// terminate scanning like any other character that is not a valid digit.
+//
+//	exponent = ( "e" | "E" | "p" | "P" ) [ sign ] digits .
+//	sign     = "+" | "-" .
+//	digits   = digit { [ '_' ] digit } .
+//	digit    = "0" ... "9" .
+//
+// A base 2 exponent is only permitted if base2ok is set.
+func scanExponent(r io.ByteScanner, base2ok, sepOk bool) (exp int64, base int, err error) {
+	// one char look-ahead
+	ch, err := r.ReadByte()
+	if err != nil {
+		if err == io.EOF {
+			err = nil
+		}
+		return 0, 10, err
+	}
+
+	// exponent char
+	switch ch {
+	case 'e', 'E':
+		base = 10
+	case 'p', 'P':
+		if base2ok {
+			base = 2
+			break // ok
+		}
+		fallthrough // binary exponent not permitted
+	default:
+		r.UnreadByte() // ch does not belong to exponent anymore
+		return 0, 10, nil
+	}
+
+	// sign
+	var digits []byte
+	ch, err = r.ReadByte()
+	if err == nil && (ch == '+' || ch == '-') {
+		if ch == '-' {
+			digits = append(digits, '-')
+		}
+		ch, err = r.ReadByte()
+	}
+
+	// prev encodes the previously seen char: it is one
+	// of '_', '0' (a digit), or '.' (anything else). A
+	// valid separator '_' may only occur after a digit.
+	prev := '.'
+	invalSep := false
+
+	// exponent value
+	hasDigits := false
+	for err == nil {
+		if '0' <= ch && ch <= '9' {
+			digits = append(digits, ch)
+			prev = '0'
+			hasDigits = true
+		} else if ch == '_' && sepOk {
+			if prev != '0' {
+				invalSep = true
+			}
+			prev = '_'
+		} else {
+			r.UnreadByte() // ch does not belong to number anymore
+			break
+		}
+		ch, err = r.ReadByte()
+	}
+
+	if err == io.EOF {
+		err = nil
+	}
+	if err == nil && !hasDigits {
+		err = errNoDigits
+	}
+	if err == nil {
+		exp, err = strconv.ParseInt(string(digits), 10, 64)
+	}
+	// other errors take precedence over invalid separators
+	if err == nil && (invalSep || prev == '_') {
+		err = errInvalSep
+	}
+
+	return
+}
+
+// String returns a string representation of x in the form "a/b" (even if b == 1).
+func (x *Rat) String() string {
+	return string(x.marshal())
+}
+
+// marshal implements String returning a slice of bytes
+func (x *Rat) marshal() []byte {
+	var buf []byte
+	buf = x.a.Append(buf, 10)
+	buf = append(buf, '/')
+	if len(x.b.abs) != 0 {
+		buf = x.b.Append(buf, 10)
+	} else {
+		buf = append(buf, '1')
+	}
+	return buf
+}
+
+// RatString returns a string representation of x in the form "a/b" if b != 1,
+// and in the form "a" if b == 1.
+func (x *Rat) RatString() string {
+	if x.IsInt() {
+		return x.a.String()
+	}
+	return x.String()
+}
+
+// FloatString returns a string representation of x in decimal form with prec
+// digits of precision after the radix point. The last digit is rounded to
+// nearest, with halves rounded away from zero.
+func (x *Rat) FloatString(prec int) string {
+	var buf []byte
+
+	if x.IsInt() {
+		buf = x.a.Append(buf, 10)
+		if prec > 0 {
+			buf = append(buf, '.')
+			for i := prec; i > 0; i-- {
+				buf = append(buf, '0')
+			}
+		}
+		return string(buf)
+	}
+	// x.b.abs != 0
+
+	q, r := nat(nil).div(nat(nil), x.a.abs, x.b.abs)
+
+	p := natOne
+	if prec > 0 {
+		p = nat(nil).expNN(natTen, nat(nil).setUint64(uint64(prec)), nil)
+	}
+
+	r = r.mul(r, p)
+	r, r2 := r.div(nat(nil), r, x.b.abs)
+
+	// see if we need to round up
+	r2 = r2.add(r2, r2)
+	if x.b.abs.cmp(r2) <= 0 {
+		r = r.add(r, natOne)
+		if r.cmp(p) >= 0 {
+			q = nat(nil).add(q, natOne)
+			r = nat(nil).sub(r, p)
+		}
+	}
+
+	if x.a.neg {
+		buf = append(buf, '-')
+	}
+	buf = append(buf, q.utoa(10)...) // itoa ignores sign if q == 0
+
+	if prec > 0 {
+		buf = append(buf, '.')
+		rs := r.utoa(10)
+		for i := prec - len(rs); i > 0; i-- {
+			buf = append(buf, '0')
+		}
+		buf = append(buf, rs...)
+	}
+
+	return string(buf)
+}
diff --git a/contrib/go/_std_1.19/src/math/big/ratmarsh.go b/contrib/go/_std_1.19/src/math/big/ratmarsh.go
new file mode 100644
index 0000000000..56102e845b
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/big/ratmarsh.go
@@ -0,0 +1,81 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements encoding/decoding of Rats.
+
+package big
+
+import (
+	"encoding/binary"
+	"errors"
+	"fmt"
+)
+
+// Gob codec version. Permits backward-compatible changes to the encoding.
+const ratGobVersion byte = 1
+
+// GobEncode implements the gob.GobEncoder interface.
+func (x *Rat) GobEncode() ([]byte, error) {
+	if x == nil {
+		return nil, nil
+	}
+	buf := make([]byte, 1+4+(len(x.a.abs)+len(x.b.abs))*_S) // extra bytes for version and sign bit (1), and numerator length (4)
+	i := x.b.abs.bytes(buf)
+	j := x.a.abs.bytes(buf[:i])
+	n := i - j
+	if int(uint32(n)) != n {
+		// this should never happen
+		return nil, errors.New("Rat.GobEncode: numerator too large")
+	}
+	binary.BigEndian.PutUint32(buf[j-4:j], uint32(n))
+	j -= 1 + 4
+	b := ratGobVersion << 1 // make space for sign bit
+	if x.a.neg {
+		b |= 1
+	}
+	buf[j] = b
+	return buf[j:], nil
+}
+
+// GobDecode implements the gob.GobDecoder interface.
+func (z *Rat) GobDecode(buf []byte) error {
+	if len(buf) == 0 {
+		// Other side sent a nil or default value.
+		*z = Rat{}
+		return nil
+	}
+	if len(buf) < 5 {
+		return errors.New("Rat.GobDecode: buffer too small")
+	}
+	b := buf[0]
+	if b>>1 != ratGobVersion {
+		return fmt.Errorf("Rat.GobDecode: encoding version %d not supported", b>>1)
+	}
+	const j = 1 + 4
+	i := j + binary.BigEndian.Uint32(buf[j-4:j])
+	if len(buf) < int(i) {
+		return errors.New("Rat.GobDecode: buffer too small")
+	}
+	z.a.neg = b&1 != 0
+	z.a.abs = z.a.abs.setBytes(buf[j:i])
+	z.b.abs = z.b.abs.setBytes(buf[i:])
+	return nil
+}
+
+// MarshalText implements the encoding.TextMarshaler interface.
+func (x *Rat) MarshalText() (text []byte, err error) {
+	if x.IsInt() {
+		return x.a.MarshalText()
+	}
+	return x.marshal(), nil
+}
+
+// UnmarshalText implements the encoding.TextUnmarshaler interface.
+func (z *Rat) UnmarshalText(text []byte) error {
+	// TODO(gri): get rid of the []byte/string conversion
+	if _, ok := z.SetString(string(text)); !ok {
+		return fmt.Errorf("math/big: cannot unmarshal %q into a *big.Rat", text)
+	}
+	return nil
+}
diff --git a/contrib/go/_std_1.18/src/math/big/roundingmode_string.go b/contrib/go/_std_1.19/src/math/big/roundingmode_string.go
index c7629eb98b..c7629eb98b 100644
--- a/contrib/go/_std_1.18/src/math/big/roundingmode_string.go
+++ b/contrib/go/_std_1.19/src/math/big/roundingmode_string.go
diff --git a/contrib/go/_std_1.19/src/math/big/sqrt.go b/contrib/go/_std_1.19/src/math/big/sqrt.go
new file mode 100644
index 0000000000..b4b03743f4
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/big/sqrt.go
@@ -0,0 +1,130 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package big
+
+import (
+	"math"
+	"sync"
+)
+
+var threeOnce struct {
+	sync.Once
+	v *Float
+}
+
+func three() *Float {
+	threeOnce.Do(func() {
+		threeOnce.v = NewFloat(3.0)
+	})
+	return threeOnce.v
+}
+
+// Sqrt sets z to the rounded square root of x, and returns it.
+//
+// If z's precision is 0, it is changed to x's precision before the
+// operation. Rounding is performed according to z's precision and
+// rounding mode, but z's accuracy is not computed. Specifically, the
+// result of z.Acc() is undefined.
+//
+// The function panics if z < 0. The value of z is undefined in that
+// case.
+func (z *Float) Sqrt(x *Float) *Float {
+	if debugFloat {
+		x.validate()
+	}
+
+	if z.prec == 0 {
+		z.prec = x.prec
+	}
+
+	if x.Sign() == -1 {
+		// following IEEE754-2008 (section 7.2)
+		panic(ErrNaN{"square root of negative operand"})
+	}
+
+	// handle ±0 and +∞
+	if x.form != finite {
+		z.acc = Exact
+		z.form = x.form
+		z.neg = x.neg // IEEE754-2008 requires √±0 = ±0
+		return z
+	}
+
+	// MantExp sets the argument's precision to the receiver's, and
+	// when z.prec > x.prec this will lower z.prec. Restore it after
+	// the MantExp call.
+	prec := z.prec
+	b := x.MantExp(z)
+	z.prec = prec
+
+	// Compute √(z·2**b) as
+	//   √( z)·2**(½b)     if b is even
+	//   √(2z)·2**(⌊½b⌋)   if b > 0 is odd
+	//   √(½z)·2**(⌈½b⌉)   if b < 0 is odd
+	switch b % 2 {
+	case 0:
+		// nothing to do
+	case 1:
+		z.exp++
+	case -1:
+		z.exp--
+	}
+	// 0.25 <= z < 2.0
+
+	// Solving 1/x² - z = 0 avoids Quo calls and is faster, especially
+	// for high precisions.
+	z.sqrtInverse(z)
+
+	// re-attach halved exponent
+	return z.SetMantExp(z, b/2)
+}
+
+// Compute √x (to z.prec precision) by solving
+//
+//	1/t² - x = 0
+//
+// for t (using Newton's method), and then inverting.
+func (z *Float) sqrtInverse(x *Float) {
+	// let
+	//   f(t) = 1/t² - x
+	// then
+	//   g(t) = f(t)/f'(t) = -½t(1 - xt²)
+	// and the next guess is given by
+	//   t2 = t - g(t) = ½t(3 - xt²)
+	u := newFloat(z.prec)
+	v := newFloat(z.prec)
+	three := three()
+	ng := func(t *Float) *Float {
+		u.prec = t.prec
+		v.prec = t.prec
+		u.Mul(t, t)     // u = t²
+		u.Mul(x, u)     //   = xt²
+		v.Sub(three, u) // v = 3 - xt²
+		u.Mul(t, v)     // u = t(3 - xt²)
+		u.exp--         //   = ½t(3 - xt²)
+		return t.Set(u)
+	}
+
+	xf, _ := x.Float64()
+	sqi := newFloat(z.prec)
+	sqi.SetFloat64(1 / math.Sqrt(xf))
+	for prec := z.prec + 32; sqi.prec < prec; {
+		sqi.prec *= 2
+		sqi = ng(sqi)
+	}
+	// sqi = 1/√x
+
+	// x/√x = √x
+	z.Mul(x, sqi)
+}
+
+// newFloat returns a new *Float with space for twice the given
+// precision.
+func newFloat(prec2 uint32) *Float {
+	z := new(Float)
+	// nat.make ensures the slice length is > 0
+	z.mant = z.mant.make(int(prec2/_W) * 2)
+	return z
+}
diff --git a/contrib/go/_std_1.19/src/math/bits.go b/contrib/go/_std_1.19/src/math/bits.go
new file mode 100644
index 0000000000..c5cb93b159
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/bits.go
@@ -0,0 +1,62 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+const (
+	uvnan    = 0x7FF8000000000001
+	uvinf    = 0x7FF0000000000000
+	uvneginf = 0xFFF0000000000000
+	uvone    = 0x3FF0000000000000
+	mask     = 0x7FF
+	shift    = 64 - 11 - 1
+	bias     = 1023
+	signMask = 1 << 63
+	fracMask = 1<<shift - 1
+)
+
+// Inf returns positive infinity if sign >= 0, negative infinity if sign < 0.
+func Inf(sign int) float64 {
+	var v uint64
+	if sign >= 0 {
+		v = uvinf
+	} else {
+		v = uvneginf
+	}
+	return Float64frombits(v)
+}
+
+// NaN returns an IEEE 754 “not-a-number” value.
+func NaN() float64 { return Float64frombits(uvnan) }
+
+// IsNaN reports whether f is an IEEE 754 “not-a-number” value.
+func IsNaN(f float64) (is bool) {
+	// IEEE 754 says that only NaNs satisfy f != f.
+	// To avoid the floating-point hardware, could use:
+	//	x := Float64bits(f);
+	//	return uint32(x>>shift)&mask == mask && x != uvinf && x != uvneginf
+	return f != f
+}
+
+// IsInf reports whether f is an infinity, according to sign.
+// If sign > 0, IsInf reports whether f is positive infinity.
+// If sign < 0, IsInf reports whether f is negative infinity.
+// If sign == 0, IsInf reports whether f is either infinity.
+func IsInf(f float64, sign int) bool {
+	// Test for infinity by comparing against maximum float.
+	// To avoid the floating-point hardware, could use:
+	//	x := Float64bits(f);
+	//	return sign >= 0 && x == uvinf || sign <= 0 && x == uvneginf;
+	return sign >= 0 && f > MaxFloat64 || sign <= 0 && f < -MaxFloat64
+}
+
+// normalize returns a normal number y and exponent exp
+// satisfying x == y × 2**exp. It assumes x is finite and non-zero.
+func normalize(x float64) (y float64, exp int) {
+	const SmallestNormal = 2.2250738585072014e-308 // 2**-1022
+	if Abs(x) < SmallestNormal {
+		return x * (1 << 52), -52
+	}
+	return x, 0
+}
diff --git a/contrib/go/_std_1.18/src/math/bits/bits.go b/contrib/go/_std_1.19/src/math/bits/bits.go
index 65452feda2..65452feda2 100644
--- a/contrib/go/_std_1.18/src/math/bits/bits.go
+++ b/contrib/go/_std_1.19/src/math/bits/bits.go
diff --git a/contrib/go/_std_1.18/src/math/bits/bits_errors.go b/contrib/go/_std_1.19/src/math/bits/bits_errors.go
index 61cb5c9457..61cb5c9457 100644
--- a/contrib/go/_std_1.18/src/math/bits/bits_errors.go
+++ b/contrib/go/_std_1.19/src/math/bits/bits_errors.go
diff --git a/contrib/go/_std_1.18/src/math/bits/bits_tables.go b/contrib/go/_std_1.19/src/math/bits/bits_tables.go
index f869b8d5c3..f869b8d5c3 100644
--- a/contrib/go/_std_1.18/src/math/bits/bits_tables.go
+++ b/contrib/go/_std_1.19/src/math/bits/bits_tables.go
diff --git a/contrib/go/_std_1.19/src/math/cbrt.go b/contrib/go/_std_1.19/src/math/cbrt.go
new file mode 100644
index 0000000000..e5e9548cb1
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/cbrt.go
@@ -0,0 +1,85 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// The go code is a modified version of the original C code from
+// http://www.netlib.org/fdlibm/s_cbrt.c and came with this notice.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunSoft, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+
+// Cbrt returns the cube root of x.
+//
+// Special cases are:
+//
+//	Cbrt(±0) = ±0
+//	Cbrt(±Inf) = ±Inf
+//	Cbrt(NaN) = NaN
+func Cbrt(x float64) float64 {
+	if haveArchCbrt {
+		return archCbrt(x)
+	}
+	return cbrt(x)
+}
+
+func cbrt(x float64) float64 {
+	const (
+		B1             = 715094163                   // (682-0.03306235651)*2**20
+		B2             = 696219795                   // (664-0.03306235651)*2**20
+		C              = 5.42857142857142815906e-01  // 19/35     = 0x3FE15F15F15F15F1
+		D              = -7.05306122448979611050e-01 // -864/1225 = 0xBFE691DE2532C834
+		E              = 1.41428571428571436819e+00  // 99/70     = 0x3FF6A0EA0EA0EA0F
+		F              = 1.60714285714285720630e+00  // 45/28     = 0x3FF9B6DB6DB6DB6E
+		G              = 3.57142857142857150787e-01  // 5/14      = 0x3FD6DB6DB6DB6DB7
+		SmallestNormal = 2.22507385850720138309e-308 // 2**-1022  = 0x0010000000000000
+	)
+	// special cases
+	switch {
+	case x == 0 || IsNaN(x) || IsInf(x, 0):
+		return x
+	}
+
+	sign := false
+	if x < 0 {
+		x = -x
+		sign = true
+	}
+
+	// rough cbrt to 5 bits
+	t := Float64frombits(Float64bits(x)/3 + B1<<32)
+	if x < SmallestNormal {
+		// subnormal number
+		t = float64(1 << 54) // set t= 2**54
+		t *= x
+		t = Float64frombits(Float64bits(t)/3 + B2<<32)
+	}
+
+	// new cbrt to 23 bits
+	r := t * t / x
+	s := C + r*t
+	t *= G + F/(s+E+D/s)
+
+	// chop to 22 bits, make larger than cbrt(x)
+	t = Float64frombits(Float64bits(t)&(0xFFFFFFFFC<<28) + 1<<30)
+
+	// one step newton iteration to 53 bits with error less than 0.667ulps
+	s = t * t // t*t is exact
+	r = x / s
+	w := t + t
+	r = (r - t) / (w + r) // r-s is exact
+	t = t + t*r
+
+	// restore the sign bit
+	if sign {
+		t = -t
+	}
+	return t
+}
diff --git a/contrib/go/_std_1.18/src/math/const.go b/contrib/go/_std_1.19/src/math/const.go
index 5ea935fb42..5ea935fb42 100644
--- a/contrib/go/_std_1.18/src/math/const.go
+++ b/contrib/go/_std_1.19/src/math/const.go
diff --git a/contrib/go/_std_1.19/src/math/copysign.go b/contrib/go/_std_1.19/src/math/copysign.go
new file mode 100644
index 0000000000..3a30afb413
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/copysign.go
@@ -0,0 +1,12 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Copysign returns a value with the magnitude of f
+// and the sign of sign.
+func Copysign(f, sign float64) float64 {
+	const signBit = 1 << 63
+	return Float64frombits(Float64bits(f)&^signBit | Float64bits(sign)&signBit)
+}
diff --git a/contrib/go/_std_1.19/src/math/dim.go b/contrib/go/_std_1.19/src/math/dim.go
new file mode 100644
index 0000000000..6a286cdc75
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/dim.go
@@ -0,0 +1,94 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Dim returns the maximum of x-y or 0.
+//
+// Special cases are:
+//
+//	Dim(+Inf, +Inf) = NaN
+//	Dim(-Inf, -Inf) = NaN
+//	Dim(x, NaN) = Dim(NaN, x) = NaN
+func Dim(x, y float64) float64 {
+	// The special cases result in NaN after the subtraction:
+	//      +Inf - +Inf = NaN
+	//      -Inf - -Inf = NaN
+	//       NaN - y    = NaN
+	//         x - NaN  = NaN
+	v := x - y
+	if v <= 0 {
+		// v is negative or 0
+		return 0
+	}
+	// v is positive or NaN
+	return v
+}
+
+// Max returns the larger of x or y.
+//
+// Special cases are:
+//
+//	Max(x, +Inf) = Max(+Inf, x) = +Inf
+//	Max(x, NaN) = Max(NaN, x) = NaN
+//	Max(+0, ±0) = Max(±0, +0) = +0
+//	Max(-0, -0) = -0
+func Max(x, y float64) float64 {
+	if haveArchMax {
+		return archMax(x, y)
+	}
+	return max(x, y)
+}
+
+func max(x, y float64) float64 {
+	// special cases
+	switch {
+	case IsInf(x, 1) || IsInf(y, 1):
+		return Inf(1)
+	case IsNaN(x) || IsNaN(y):
+		return NaN()
+	case x == 0 && x == y:
+		if Signbit(x) {
+			return y
+		}
+		return x
+	}
+	if x > y {
+		return x
+	}
+	return y
+}
+
+// Min returns the smaller of x or y.
+//
+// Special cases are:
+//
+//	Min(x, -Inf) = Min(-Inf, x) = -Inf
+//	Min(x, NaN) = Min(NaN, x) = NaN
+//	Min(-0, ±0) = Min(±0, -0) = -0
+func Min(x, y float64) float64 {
+	if haveArchMin {
+		return archMin(x, y)
+	}
+	return min(x, y)
+}
+
+func min(x, y float64) float64 {
+	// special cases
+	switch {
+	case IsInf(x, -1) || IsInf(y, -1):
+		return Inf(-1)
+	case IsNaN(x) || IsNaN(y):
+		return NaN()
+	case x == 0 && x == y:
+		if Signbit(x) {
+			return x
+		}
+		return y
+	}
+	if x < y {
+		return x
+	}
+	return y
+}
diff --git a/contrib/go/_std_1.18/src/math/dim_amd64.s b/contrib/go/_std_1.19/src/math/dim_amd64.s
index 253f03b97e..253f03b97e 100644
--- a/contrib/go/_std_1.18/src/math/dim_amd64.s
+++ b/contrib/go/_std_1.19/src/math/dim_amd64.s
diff --git a/contrib/go/_std_1.18/src/math/dim_asm.go b/contrib/go/_std_1.19/src/math/dim_asm.go
index f4adbd0ae5..f4adbd0ae5 100644
--- a/contrib/go/_std_1.18/src/math/dim_asm.go
+++ b/contrib/go/_std_1.19/src/math/dim_asm.go
diff --git a/contrib/go/_std_1.19/src/math/erf.go b/contrib/go/_std_1.19/src/math/erf.go
new file mode 100644
index 0000000000..ba00c7d03e
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/erf.go
@@ -0,0 +1,351 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+	Floating-point error function and complementary error function.
+*/
+
+// The original C code and the long comment below are
+// from FreeBSD's /usr/src/lib/msun/src/s_erf.c and
+// came with this notice. The go code is a simplified
+// version of the original C.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+//
+// double erf(double x)
+// double erfc(double x)
+//                           x
+//                    2      |\
+//     erf(x)  =  ---------  | exp(-t*t)dt
+//                 sqrt(pi) \|
+//                           0
+//
+//     erfc(x) =  1-erf(x)
+//  Note that
+//              erf(-x) = -erf(x)
+//              erfc(-x) = 2 - erfc(x)
+//
+// Method:
+//      1. For |x| in [0, 0.84375]
+//          erf(x)  = x + x*R(x**2)
+//          erfc(x) = 1 - erf(x)           if x in [-.84375,0.25]
+//                  = 0.5 + ((0.5-x)-x*R)  if x in [0.25,0.84375]
+//         where R = P/Q where P is an odd poly of degree 8 and
+//         Q is an odd poly of degree 10.
+//                                               -57.90
+//                      | R - (erf(x)-x)/x | <= 2
+//
+//
+//         Remark. The formula is derived by noting
+//          erf(x) = (2/sqrt(pi))*(x - x**3/3 + x**5/10 - x**7/42 + ....)
+//         and that
+//          2/sqrt(pi) = 1.128379167095512573896158903121545171688
+//         is close to one. The interval is chosen because the fix
+//         point of erf(x) is near 0.6174 (i.e., erf(x)=x when x is
+//         near 0.6174), and by some experiment, 0.84375 is chosen to
+//         guarantee the error is less than one ulp for erf.
+//
+//      2. For |x| in [0.84375,1.25], let s = |x| - 1, and
+//         c = 0.84506291151 rounded to single (24 bits)
+//              erf(x)  = sign(x) * (c  + P1(s)/Q1(s))
+//              erfc(x) = (1-c)  - P1(s)/Q1(s) if x > 0
+//                        1+(c+P1(s)/Q1(s))    if x < 0
+//              |P1/Q1 - (erf(|x|)-c)| <= 2**-59.06
+//         Remark: here we use the taylor series expansion at x=1.
+//              erf(1+s) = erf(1) + s*Poly(s)
+//                       = 0.845.. + P1(s)/Q1(s)
+//         That is, we use rational approximation to approximate
+//                      erf(1+s) - (c = (single)0.84506291151)
+//         Note that |P1/Q1|< 0.078 for x in [0.84375,1.25]
+//         where
+//              P1(s) = degree 6 poly in s
+//              Q1(s) = degree 6 poly in s
+//
+//      3. For x in [1.25,1/0.35(~2.857143)],
+//              erfc(x) = (1/x)*exp(-x*x-0.5625+R1/S1)
+//              erf(x)  = 1 - erfc(x)
+//         where
+//              R1(z) = degree 7 poly in z, (z=1/x**2)
+//              S1(z) = degree 8 poly in z
+//
+//      4. For x in [1/0.35,28]
+//              erfc(x) = (1/x)*exp(-x*x-0.5625+R2/S2) if x > 0
+//                      = 2.0 - (1/x)*exp(-x*x-0.5625+R2/S2) if -6<x<0
+//                      = 2.0 - tiny            (if x <= -6)
+//              erf(x)  = sign(x)*(1.0 - erfc(x)) if x < 6, else
+//              erf(x)  = sign(x)*(1.0 - tiny)
+//         where
+//              R2(z) = degree 6 poly in z, (z=1/x**2)
+//              S2(z) = degree 7 poly in z
+//
+//      Note1:
+//         To compute exp(-x*x-0.5625+R/S), let s be a single
+//         precision number and s := x; then
+//              -x*x = -s*s + (s-x)*(s+x)
+//              exp(-x*x-0.5626+R/S) =
+//                      exp(-s*s-0.5625)*exp((s-x)*(s+x)+R/S);
+//      Note2:
+//         Here 4 and 5 make use of the asymptotic series
+//                        exp(-x*x)
+//              erfc(x) ~ ---------- * ( 1 + Poly(1/x**2) )
+//                        x*sqrt(pi)
+//         We use rational approximation to approximate
+//              g(s)=f(1/x**2) = log(erfc(x)*x) - x*x + 0.5625
+//         Here is the error bound for R1/S1 and R2/S2
+//              |R1/S1 - f(x)|  < 2**(-62.57)
+//              |R2/S2 - f(x)|  < 2**(-61.52)
+//
+//      5. For inf > x >= 28
+//              erf(x)  = sign(x) *(1 - tiny)  (raise inexact)
+//              erfc(x) = tiny*tiny (raise underflow) if x > 0
+//                      = 2 - tiny if x<0
+//
+//      7. Special case:
+//              erf(0)  = 0, erf(inf)  = 1, erf(-inf) = -1,
+//              erfc(0) = 1, erfc(inf) = 0, erfc(-inf) = 2,
+//              erfc/erf(NaN) is NaN
+
+const (
+	erx = 8.45062911510467529297e-01 // 0x3FEB0AC160000000
+	// Coefficients for approximation to  erf in [0, 0.84375]
+	efx  = 1.28379167095512586316e-01  // 0x3FC06EBA8214DB69
+	efx8 = 1.02703333676410069053e+00  // 0x3FF06EBA8214DB69
+	pp0  = 1.28379167095512558561e-01  // 0x3FC06EBA8214DB68
+	pp1  = -3.25042107247001499370e-01 // 0xBFD4CD7D691CB913
+	pp2  = -2.84817495755985104766e-02 // 0xBF9D2A51DBD7194F
+	pp3  = -5.77027029648944159157e-03 // 0xBF77A291236668E4
+	pp4  = -2.37630166566501626084e-05 // 0xBEF8EAD6120016AC
+	qq1  = 3.97917223959155352819e-01  // 0x3FD97779CDDADC09
+	qq2  = 6.50222499887672944485e-02  // 0x3FB0A54C5536CEBA
+	qq3  = 5.08130628187576562776e-03  // 0x3F74D022C4D36B0F
+	qq4  = 1.32494738004321644526e-04  // 0x3F215DC9221C1A10
+	qq5  = -3.96022827877536812320e-06 // 0xBED09C4342A26120
+	// Coefficients for approximation to  erf  in [0.84375, 1.25]
+	pa0 = -2.36211856075265944077e-03 // 0xBF6359B8BEF77538
+	pa1 = 4.14856118683748331666e-01  // 0x3FDA8D00AD92B34D
+	pa2 = -3.72207876035701323847e-01 // 0xBFD7D240FBB8C3F1
+	pa3 = 3.18346619901161753674e-01  // 0x3FD45FCA805120E4
+	pa4 = -1.10894694282396677476e-01 // 0xBFBC63983D3E28EC
+	pa5 = 3.54783043256182359371e-02  // 0x3FA22A36599795EB
+	pa6 = -2.16637559486879084300e-03 // 0xBF61BF380A96073F
+	qa1 = 1.06420880400844228286e-01  // 0x3FBB3E6618EEE323
+	qa2 = 5.40397917702171048937e-01  // 0x3FE14AF092EB6F33
+	qa3 = 7.18286544141962662868e-02  // 0x3FB2635CD99FE9A7
+	qa4 = 1.26171219808761642112e-01  // 0x3FC02660E763351F
+	qa5 = 1.36370839120290507362e-02  // 0x3F8BEDC26B51DD1C
+	qa6 = 1.19844998467991074170e-02  // 0x3F888B545735151D
+	// Coefficients for approximation to  erfc in [1.25, 1/0.35]
+	ra0 = -9.86494403484714822705e-03 // 0xBF843412600D6435
+	ra1 = -6.93858572707181764372e-01 // 0xBFE63416E4BA7360
+	ra2 = -1.05586262253232909814e+01 // 0xC0251E0441B0E726
+	ra3 = -6.23753324503260060396e+01 // 0xC04F300AE4CBA38D
+	ra4 = -1.62396669462573470355e+02 // 0xC0644CB184282266
+	ra5 = -1.84605092906711035994e+02 // 0xC067135CEBCCABB2
+	ra6 = -8.12874355063065934246e+01 // 0xC054526557E4D2F2
+	ra7 = -9.81432934416914548592e+00 // 0xC023A0EFC69AC25C
+	sa1 = 1.96512716674392571292e+01  // 0x4033A6B9BD707687
+	sa2 = 1.37657754143519042600e+02  // 0x4061350C526AE721
+	sa3 = 4.34565877475229228821e+02  // 0x407B290DD58A1A71
+	sa4 = 6.45387271733267880336e+02  // 0x40842B1921EC2868
+	sa5 = 4.29008140027567833386e+02  // 0x407AD02157700314
+	sa6 = 1.08635005541779435134e+02  // 0x405B28A3EE48AE2C
+	sa7 = 6.57024977031928170135e+00  // 0x401A47EF8E484A93
+	sa8 = -6.04244152148580987438e-02 // 0xBFAEEFF2EE749A62
+	// Coefficients for approximation to  erfc in [1/.35, 28]
+	rb0 = -9.86494292470009928597e-03 // 0xBF84341239E86F4A
+	rb1 = -7.99283237680523006574e-01 // 0xBFE993BA70C285DE
+	rb2 = -1.77579549177547519889e+01 // 0xC031C209555F995A
+	rb3 = -1.60636384855821916062e+02 // 0xC064145D43C5ED98
+	rb4 = -6.37566443368389627722e+02 // 0xC083EC881375F228
+	rb5 = -1.02509513161107724954e+03 // 0xC09004616A2E5992
+	rb6 = -4.83519191608651397019e+02 // 0xC07E384E9BDC383F
+	sb1 = 3.03380607434824582924e+01  // 0x403E568B261D5190
+	sb2 = 3.25792512996573918826e+02  // 0x40745CAE221B9F0A
+	sb3 = 1.53672958608443695994e+03  // 0x409802EB189D5118
+	sb4 = 3.19985821950859553908e+03  // 0x40A8FFB7688C246A
+	sb5 = 2.55305040643316442583e+03  // 0x40A3F219CEDF3BE6
+	sb6 = 4.74528541206955367215e+02  // 0x407DA874E79FE763
+	sb7 = -2.24409524465858183362e+01 // 0xC03670E242712D62
+)
+
+// Erf returns the error function of x.
+//
+// Special cases are:
+//
+//	Erf(+Inf) = 1
+//	Erf(-Inf) = -1
+//	Erf(NaN) = NaN
+func Erf(x float64) float64 {
+	if haveArchErf {
+		return archErf(x)
+	}
+	return erf(x)
+}
+
+func erf(x float64) float64 {
+	const (
+		VeryTiny = 2.848094538889218e-306 // 0x0080000000000000
+		Small    = 1.0 / (1 << 28)        // 2**-28
+	)
+	// special cases
+	switch {
+	case IsNaN(x):
+		return NaN()
+	case IsInf(x, 1):
+		return 1
+	case IsInf(x, -1):
+		return -1
+	}
+	sign := false
+	if x < 0 {
+		x = -x
+		sign = true
+	}
+	if x < 0.84375 { // |x| < 0.84375
+		var temp float64
+		if x < Small { // |x| < 2**-28
+			if x < VeryTiny {
+				temp = 0.125 * (8.0*x + efx8*x) // avoid underflow
+			} else {
+				temp = x + efx*x
+			}
+		} else {
+			z := x * x
+			r := pp0 + z*(pp1+z*(pp2+z*(pp3+z*pp4)))
+			s := 1 + z*(qq1+z*(qq2+z*(qq3+z*(qq4+z*qq5))))
+			y := r / s
+			temp = x + x*y
+		}
+		if sign {
+			return -temp
+		}
+		return temp
+	}
+	if x < 1.25 { // 0.84375 <= |x| < 1.25
+		s := x - 1
+		P := pa0 + s*(pa1+s*(pa2+s*(pa3+s*(pa4+s*(pa5+s*pa6)))))
+		Q := 1 + s*(qa1+s*(qa2+s*(qa3+s*(qa4+s*(qa5+s*qa6)))))
+		if sign {
+			return -erx - P/Q
+		}
+		return erx + P/Q
+	}
+	if x >= 6 { // inf > |x| >= 6
+		if sign {
+			return -1
+		}
+		return 1
+	}
+	s := 1 / (x * x)
+	var R, S float64
+	if x < 1/0.35 { // |x| < 1 / 0.35  ~ 2.857143
+		R = ra0 + s*(ra1+s*(ra2+s*(ra3+s*(ra4+s*(ra5+s*(ra6+s*ra7))))))
+		S = 1 + s*(sa1+s*(sa2+s*(sa3+s*(sa4+s*(sa5+s*(sa6+s*(sa7+s*sa8)))))))
+	} else { // |x| >= 1 / 0.35  ~ 2.857143
+		R = rb0 + s*(rb1+s*(rb2+s*(rb3+s*(rb4+s*(rb5+s*rb6)))))
+		S = 1 + s*(sb1+s*(sb2+s*(sb3+s*(sb4+s*(sb5+s*(sb6+s*sb7))))))
+	}
+	z := Float64frombits(Float64bits(x) & 0xffffffff00000000) // pseudo-single (20-bit) precision x
+	r := Exp(-z*z-0.5625) * Exp((z-x)*(z+x)+R/S)
+	if sign {
+		return r/x - 1
+	}
+	return 1 - r/x
+}
+
+// Erfc returns the complementary error function of x.
+//
+// Special cases are:
+//
+//	Erfc(+Inf) = 0
+//	Erfc(-Inf) = 2
+//	Erfc(NaN) = NaN
+func Erfc(x float64) float64 {
+	if haveArchErfc {
+		return archErfc(x)
+	}
+	return erfc(x)
+}
+
+func erfc(x float64) float64 {
+	const Tiny = 1.0 / (1 << 56) // 2**-56
+	// special cases
+	switch {
+	case IsNaN(x):
+		return NaN()
+	case IsInf(x, 1):
+		return 0
+	case IsInf(x, -1):
+		return 2
+	}
+	sign := false
+	if x < 0 {
+		x = -x
+		sign = true
+	}
+	if x < 0.84375 { // |x| < 0.84375
+		var temp float64
+		if x < Tiny { // |x| < 2**-56
+			temp = x
+		} else {
+			z := x * x
+			r := pp0 + z*(pp1+z*(pp2+z*(pp3+z*pp4)))
+			s := 1 + z*(qq1+z*(qq2+z*(qq3+z*(qq4+z*qq5))))
+			y := r / s
+			if x < 0.25 { // |x| < 1/4
+				temp = x + x*y
+			} else {
+				temp = 0.5 + (x*y + (x - 0.5))
+			}
+		}
+		if sign {
+			return 1 + temp
+		}
+		return 1 - temp
+	}
+	if x < 1.25 { // 0.84375 <= |x| < 1.25
+		s := x - 1
+		P := pa0 + s*(pa1+s*(pa2+s*(pa3+s*(pa4+s*(pa5+s*pa6)))))
+		Q := 1 + s*(qa1+s*(qa2+s*(qa3+s*(qa4+s*(qa5+s*qa6)))))
+		if sign {
+			return 1 + erx + P/Q
+		}
+		return 1 - erx - P/Q
+
+	}
+	if x < 28 { // |x| < 28
+		s := 1 / (x * x)
+		var R, S float64
+		if x < 1/0.35 { // |x| < 1 / 0.35 ~ 2.857143
+			R = ra0 + s*(ra1+s*(ra2+s*(ra3+s*(ra4+s*(ra5+s*(ra6+s*ra7))))))
+			S = 1 + s*(sa1+s*(sa2+s*(sa3+s*(sa4+s*(sa5+s*(sa6+s*(sa7+s*sa8)))))))
+		} else { // |x| >= 1 / 0.35 ~ 2.857143
+			if sign && x > 6 {
+				return 2 // x < -6
+			}
+			R = rb0 + s*(rb1+s*(rb2+s*(rb3+s*(rb4+s*(rb5+s*rb6)))))
+			S = 1 + s*(sb1+s*(sb2+s*(sb3+s*(sb4+s*(sb5+s*(sb6+s*sb7))))))
+		}
+		z := Float64frombits(Float64bits(x) & 0xffffffff00000000) // pseudo-single (20-bit) precision x
+		r := Exp(-z*z-0.5625) * Exp((z-x)*(z+x)+R/S)
+		if sign {
+			return 2 - r/x
+		}
+		return r / x
+	}
+	if sign {
+		return 2
+	}
+	return 0
+}
diff --git a/contrib/go/_std_1.19/src/math/erfinv.go b/contrib/go/_std_1.19/src/math/erfinv.go
new file mode 100644
index 0000000000..eed0feb42d
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/erfinv.go
@@ -0,0 +1,129 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+	Inverse of the floating-point error function.
+*/
+
+// This implementation is based on the rational approximation
+// of percentage points of normal distribution available from
+// https://www.jstor.org/stable/2347330.
+
+const (
+	// Coefficients for approximation to erf in |x| <= 0.85
+	a0 = 1.1975323115670912564578e0
+	a1 = 4.7072688112383978012285e1
+	a2 = 6.9706266534389598238465e2
+	a3 = 4.8548868893843886794648e3
+	a4 = 1.6235862515167575384252e4
+	a5 = 2.3782041382114385731252e4
+	a6 = 1.1819493347062294404278e4
+	a7 = 8.8709406962545514830200e2
+	b0 = 1.0000000000000000000e0
+	b1 = 4.2313330701600911252e1
+	b2 = 6.8718700749205790830e2
+	b3 = 5.3941960214247511077e3
+	b4 = 2.1213794301586595867e4
+	b5 = 3.9307895800092710610e4
+	b6 = 2.8729085735721942674e4
+	b7 = 5.2264952788528545610e3
+	// Coefficients for approximation to erf in 0.85 < |x| <= 1-2*exp(-25)
+	c0 = 1.42343711074968357734e0
+	c1 = 4.63033784615654529590e0
+	c2 = 5.76949722146069140550e0
+	c3 = 3.64784832476320460504e0
+	c4 = 1.27045825245236838258e0
+	c5 = 2.41780725177450611770e-1
+	c6 = 2.27238449892691845833e-2
+	c7 = 7.74545014278341407640e-4
+	d0 = 1.4142135623730950488016887e0
+	d1 = 2.9036514445419946173133295e0
+	d2 = 2.3707661626024532365971225e0
+	d3 = 9.7547832001787427186894837e-1
+	d4 = 2.0945065210512749128288442e-1
+	d5 = 2.1494160384252876777097297e-2
+	d6 = 7.7441459065157709165577218e-4
+	d7 = 1.4859850019840355905497876e-9
+	// Coefficients for approximation to erf in 1-2*exp(-25) < |x| < 1
+	e0 = 6.65790464350110377720e0
+	e1 = 5.46378491116411436990e0
+	e2 = 1.78482653991729133580e0
+	e3 = 2.96560571828504891230e-1
+	e4 = 2.65321895265761230930e-2
+	e5 = 1.24266094738807843860e-3
+	e6 = 2.71155556874348757815e-5
+	e7 = 2.01033439929228813265e-7
+	f0 = 1.414213562373095048801689e0
+	f1 = 8.482908416595164588112026e-1
+	f2 = 1.936480946950659106176712e-1
+	f3 = 2.103693768272068968719679e-2
+	f4 = 1.112800997078859844711555e-3
+	f5 = 2.611088405080593625138020e-5
+	f6 = 2.010321207683943062279931e-7
+	f7 = 2.891024605872965461538222e-15
+)
+
+// Erfinv returns the inverse error function of x.
+//
+// Special cases are:
+//
+//	Erfinv(1) = +Inf
+//	Erfinv(-1) = -Inf
+//	Erfinv(x) = NaN if x < -1 or x > 1
+//	Erfinv(NaN) = NaN
+func Erfinv(x float64) float64 {
+	// special cases
+	if IsNaN(x) || x <= -1 || x >= 1 {
+		if x == -1 || x == 1 {
+			return Inf(int(x))
+		}
+		return NaN()
+	}
+
+	sign := false
+	if x < 0 {
+		x = -x
+		sign = true
+	}
+
+	var ans float64
+	if x <= 0.85 { // |x| <= 0.85
+		r := 0.180625 - 0.25*x*x
+		z1 := ((((((a7*r+a6)*r+a5)*r+a4)*r+a3)*r+a2)*r+a1)*r + a0
+		z2 := ((((((b7*r+b6)*r+b5)*r+b4)*r+b3)*r+b2)*r+b1)*r + b0
+		ans = (x * z1) / z2
+	} else {
+		var z1, z2 float64
+		r := Sqrt(Ln2 - Log(1.0-x))
+		if r <= 5.0 {
+			r -= 1.6
+			z1 = ((((((c7*r+c6)*r+c5)*r+c4)*r+c3)*r+c2)*r+c1)*r + c0
+			z2 = ((((((d7*r+d6)*r+d5)*r+d4)*r+d3)*r+d2)*r+d1)*r + d0
+		} else {
+			r -= 5.0
+			z1 = ((((((e7*r+e6)*r+e5)*r+e4)*r+e3)*r+e2)*r+e1)*r + e0
+			z2 = ((((((f7*r+f6)*r+f5)*r+f4)*r+f3)*r+f2)*r+f1)*r + f0
+		}
+		ans = z1 / z2
+	}
+
+	if sign {
+		return -ans
+	}
+	return ans
+}
+
+// Erfcinv returns the inverse of Erfc(x).
+//
+// Special cases are:
+//
+//	Erfcinv(0) = +Inf
+//	Erfcinv(2) = -Inf
+//	Erfcinv(x) = NaN if x < 0 or x > 2
+//	Erfcinv(NaN) = NaN
+func Erfcinv(x float64) float64 {
+	return Erfinv(1 - x)
+}
diff --git a/contrib/go/_std_1.19/src/math/exp.go b/contrib/go/_std_1.19/src/math/exp.go
new file mode 100644
index 0000000000..760795f46f
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/exp.go
@@ -0,0 +1,203 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Exp returns e**x, the base-e exponential of x.
+//
+// Special cases are:
+//
+//	Exp(+Inf) = +Inf
+//	Exp(NaN) = NaN
+//
+// Very large values overflow to 0 or +Inf.
+// Very small values underflow to 1.
+func Exp(x float64) float64 {
+	if haveArchExp {
+		return archExp(x)
+	}
+	return exp(x)
+}
+
+// The original C code, the long comment, and the constants
+// below are from FreeBSD's /usr/src/lib/msun/src/e_exp.c
+// and came with this notice. The go code is a simplified
+// version of the original C.
+//
+// ====================================================
+// Copyright (C) 2004 by Sun Microsystems, Inc. All rights reserved.
+//
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+//
+// exp(x)
+// Returns the exponential of x.
+//
+// Method
+//   1. Argument reduction:
+//      Reduce x to an r so that |r| <= 0.5*ln2 ~ 0.34658.
+//      Given x, find r and integer k such that
+//
+//               x = k*ln2 + r,  |r| <= 0.5*ln2.
+//
+//      Here r will be represented as r = hi-lo for better
+//      accuracy.
+//
+//   2. Approximation of exp(r) by a special rational function on
+//      the interval [0,0.34658]:
+//      Write
+//          R(r**2) = r*(exp(r)+1)/(exp(r)-1) = 2 + r*r/6 - r**4/360 + ...
+//      We use a special Remez algorithm on [0,0.34658] to generate
+//      a polynomial of degree 5 to approximate R. The maximum error
+//      of this polynomial approximation is bounded by 2**-59. In
+//      other words,
+//          R(z) ~ 2.0 + P1*z + P2*z**2 + P3*z**3 + P4*z**4 + P5*z**5
+//      (where z=r*r, and the values of P1 to P5 are listed below)
+//      and
+//          |                  5          |     -59
+//          | 2.0+P1*z+...+P5*z   -  R(z) | <= 2
+//          |                             |
+//      The computation of exp(r) thus becomes
+//                             2*r
+//              exp(r) = 1 + -------
+//                            R - r
+//                                 r*R1(r)
+//                     = 1 + r + ----------- (for better accuracy)
+//                                2 - R1(r)
+//      where
+//                               2       4             10
+//              R1(r) = r - (P1*r  + P2*r  + ... + P5*r   ).
+//
+//   3. Scale back to obtain exp(x):
+//      From step 1, we have
+//         exp(x) = 2**k * exp(r)
+//
+// Special cases:
+//      exp(INF) is INF, exp(NaN) is NaN;
+//      exp(-INF) is 0, and
+//      for finite argument, only exp(0)=1 is exact.
+//
+// Accuracy:
+//      according to an error analysis, the error is always less than
+//      1 ulp (unit in the last place).
+//
+// Misc. info.
+//      For IEEE double
+//          if x >  7.09782712893383973096e+02 then exp(x) overflow
+//          if x < -7.45133219101941108420e+02 then exp(x) underflow
+//
+// Constants:
+// The hexadecimal values are the intended ones for the following
+// constants. The decimal values may be used, provided that the
+// compiler will convert from decimal to binary accurately enough
+// to produce the hexadecimal values shown.
+
+func exp(x float64) float64 {
+	const (
+		Ln2Hi = 6.93147180369123816490e-01
+		Ln2Lo = 1.90821492927058770002e-10
+		Log2e = 1.44269504088896338700e+00
+
+		Overflow  = 7.09782712893383973096e+02
+		Underflow = -7.45133219101941108420e+02
+		NearZero  = 1.0 / (1 << 28) // 2**-28
+	)
+
+	// special cases
+	switch {
+	case IsNaN(x) || IsInf(x, 1):
+		return x
+	case IsInf(x, -1):
+		return 0
+	case x > Overflow:
+		return Inf(1)
+	case x < Underflow:
+		return 0
+	case -NearZero < x && x < NearZero:
+		return 1 + x
+	}
+
+	// reduce; computed as r = hi - lo for extra precision.
+	var k int
+	switch {
+	case x < 0:
+		k = int(Log2e*x - 0.5)
+	case x > 0:
+		k = int(Log2e*x + 0.5)
+	}
+	hi := x - float64(k)*Ln2Hi
+	lo := float64(k) * Ln2Lo
+
+	// compute
+	return expmulti(hi, lo, k)
+}
+
+// Exp2 returns 2**x, the base-2 exponential of x.
+//
+// Special cases are the same as Exp.
+func Exp2(x float64) float64 {
+	if haveArchExp2 {
+		return archExp2(x)
+	}
+	return exp2(x)
+}
+
+func exp2(x float64) float64 {
+	const (
+		Ln2Hi = 6.93147180369123816490e-01
+		Ln2Lo = 1.90821492927058770002e-10
+
+		Overflow  = 1.0239999999999999e+03
+		Underflow = -1.0740e+03
+	)
+
+	// special cases
+	switch {
+	case IsNaN(x) || IsInf(x, 1):
+		return x
+	case IsInf(x, -1):
+		return 0
+	case x > Overflow:
+		return Inf(1)
+	case x < Underflow:
+		return 0
+	}
+
+	// argument reduction; x = r×lg(e) + k with |r| ≤ ln(2)/2.
+	// computed as r = hi - lo for extra precision.
+	var k int
+	switch {
+	case x > 0:
+		k = int(x + 0.5)
+	case x < 0:
+		k = int(x - 0.5)
+	}
+	t := x - float64(k)
+	hi := t * Ln2Hi
+	lo := -t * Ln2Lo
+
+	// compute
+	return expmulti(hi, lo, k)
+}
+
+// exp1 returns e**r × 2**k where r = hi - lo and |r| ≤ ln(2)/2.
+func expmulti(hi, lo float64, k int) float64 {
+	const (
+		P1 = 1.66666666666666657415e-01  /* 0x3FC55555; 0x55555555 */
+		P2 = -2.77777777770155933842e-03 /* 0xBF66C16C; 0x16BEBD93 */
+		P3 = 6.61375632143793436117e-05  /* 0x3F11566A; 0xAF25DE2C */
+		P4 = -1.65339022054652515390e-06 /* 0xBEBBBD41; 0xC5D26BF1 */
+		P5 = 4.13813679705723846039e-08  /* 0x3E663769; 0x72BEA4D0 */
+	)
+
+	r := hi - lo
+	t := r * r
+	c := r - t*(P1+t*(P2+t*(P3+t*(P4+t*P5))))
+	y := 1 - ((lo - (r*c)/(2-c)) - hi)
+	// TODO(rsc): make sure Ldexp can handle boundary k
+	return Ldexp(y, k)
+}
diff --git a/contrib/go/_std_1.18/src/math/exp2_noasm.go b/contrib/go/_std_1.19/src/math/exp2_noasm.go
index c2b409329f..c2b409329f 100644
--- a/contrib/go/_std_1.18/src/math/exp2_noasm.go
+++ b/contrib/go/_std_1.19/src/math/exp2_noasm.go
diff --git a/contrib/go/_std_1.18/src/math/exp_amd64.go b/contrib/go/_std_1.19/src/math/exp_amd64.go
index 0f701b1d6d..0f701b1d6d 100644
--- a/contrib/go/_std_1.18/src/math/exp_amd64.go
+++ b/contrib/go/_std_1.19/src/math/exp_amd64.go
diff --git a/contrib/go/_std_1.18/src/math/exp_amd64.s b/contrib/go/_std_1.19/src/math/exp_amd64.s
index 02b71c81eb..02b71c81eb 100644
--- a/contrib/go/_std_1.18/src/math/exp_amd64.s
+++ b/contrib/go/_std_1.19/src/math/exp_amd64.s
diff --git a/contrib/go/_std_1.18/src/math/exp_asm.go b/contrib/go/_std_1.19/src/math/exp_asm.go
index 424442845b..424442845b 100644
--- a/contrib/go/_std_1.18/src/math/exp_asm.go
+++ b/contrib/go/_std_1.19/src/math/exp_asm.go
diff --git a/contrib/go/_std_1.19/src/math/expm1.go b/contrib/go/_std_1.19/src/math/expm1.go
new file mode 100644
index 0000000000..ff1c82f524
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/expm1.go
@@ -0,0 +1,244 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// The original C code, the long comment, and the constants
+// below are from FreeBSD's /usr/src/lib/msun/src/s_expm1.c
+// and came with this notice. The go code is a simplified
+// version of the original C.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+// expm1(x)
+// Returns exp(x)-1, the exponential of x minus 1.
+//
+// Method
+//   1. Argument reduction:
+//      Given x, find r and integer k such that
+//
+//               x = k*ln2 + r,  |r| <= 0.5*ln2 ~ 0.34658
+//
+//      Here a correction term c will be computed to compensate
+//      the error in r when rounded to a floating-point number.
+//
+//   2. Approximating expm1(r) by a special rational function on
+//      the interval [0,0.34658]:
+//      Since
+//          r*(exp(r)+1)/(exp(r)-1) = 2+ r**2/6 - r**4/360 + ...
+//      we define R1(r*r) by
+//          r*(exp(r)+1)/(exp(r)-1) = 2+ r**2/6 * R1(r*r)
+//      That is,
+//          R1(r**2) = 6/r *((exp(r)+1)/(exp(r)-1) - 2/r)
+//                   = 6/r * ( 1 + 2.0*(1/(exp(r)-1) - 1/r))
+//                   = 1 - r**2/60 + r**4/2520 - r**6/100800 + ...
+//      We use a special Reme algorithm on [0,0.347] to generate
+//      a polynomial of degree 5 in r*r to approximate R1. The
+//      maximum error of this polynomial approximation is bounded
+//      by 2**-61. In other words,
+//          R1(z) ~ 1.0 + Q1*z + Q2*z**2 + Q3*z**3 + Q4*z**4 + Q5*z**5
+//      where   Q1  =  -1.6666666666666567384E-2,
+//              Q2  =   3.9682539681370365873E-4,
+//              Q3  =  -9.9206344733435987357E-6,
+//              Q4  =   2.5051361420808517002E-7,
+//              Q5  =  -6.2843505682382617102E-9;
+//      (where z=r*r, and the values of Q1 to Q5 are listed below)
+//      with error bounded by
+//          |                  5           |     -61
+//          | 1.0+Q1*z+...+Q5*z   -  R1(z) | <= 2
+//          |                              |
+//
+//      expm1(r) = exp(r)-1 is then computed by the following
+//      specific way which minimize the accumulation rounding error:
+//                             2     3
+//                            r     r    [ 3 - (R1 + R1*r/2)  ]
+//            expm1(r) = r + --- + --- * [--------------------]
+//                            2     2    [ 6 - r*(3 - R1*r/2) ]
+//
+//      To compensate the error in the argument reduction, we use
+//              expm1(r+c) = expm1(r) + c + expm1(r)*c
+//                         ~ expm1(r) + c + r*c
+//      Thus c+r*c will be added in as the correction terms for
+//      expm1(r+c). Now rearrange the term to avoid optimization
+//      screw up:
+//                      (      2                                    2 )
+//                      ({  ( r    [ R1 -  (3 - R1*r/2) ]  )  }    r  )
+//       expm1(r+c)~r - ({r*(--- * [--------------------]-c)-c} - --- )
+//                      ({  ( 2    [ 6 - r*(3 - R1*r/2) ]  )  }    2  )
+//                      (                                             )
+//
+//                 = r - E
+//   3. Scale back to obtain expm1(x):
+//      From step 1, we have
+//         expm1(x) = either 2**k*[expm1(r)+1] - 1
+//                  = or     2**k*[expm1(r) + (1-2**-k)]
+//   4. Implementation notes:
+//      (A). To save one multiplication, we scale the coefficient Qi
+//           to Qi*2**i, and replace z by (x**2)/2.
+//      (B). To achieve maximum accuracy, we compute expm1(x) by
+//        (i)   if x < -56*ln2, return -1.0, (raise inexact if x!=inf)
+//        (ii)  if k=0, return r-E
+//        (iii) if k=-1, return 0.5*(r-E)-0.5
+//        (iv)  if k=1 if r < -0.25, return 2*((r+0.5)- E)
+//                     else          return  1.0+2.0*(r-E);
+//        (v)   if (k<-2||k>56) return 2**k(1-(E-r)) - 1 (or exp(x)-1)
+//        (vi)  if k <= 20, return 2**k((1-2**-k)-(E-r)), else
+//        (vii) return 2**k(1-((E+2**-k)-r))
+//
+// Special cases:
+//      expm1(INF) is INF, expm1(NaN) is NaN;
+//      expm1(-INF) is -1, and
+//      for finite argument, only expm1(0)=0 is exact.
+//
+// Accuracy:
+//      according to an error analysis, the error is always less than
+//      1 ulp (unit in the last place).
+//
+// Misc. info.
+//      For IEEE double
+//          if x >  7.09782712893383973096e+02 then expm1(x) overflow
+//
+// Constants:
+// The hexadecimal values are the intended ones for the following
+// constants. The decimal values may be used, provided that the
+// compiler will convert from decimal to binary accurately enough
+// to produce the hexadecimal values shown.
+//
+
+// Expm1 returns e**x - 1, the base-e exponential of x minus 1.
+// It is more accurate than Exp(x) - 1 when x is near zero.
+//
+// Special cases are:
+//
+//	Expm1(+Inf) = +Inf
+//	Expm1(-Inf) = -1
+//	Expm1(NaN) = NaN
+//
+// Very large values overflow to -1 or +Inf.
+func Expm1(x float64) float64 {
+	if haveArchExpm1 {
+		return archExpm1(x)
+	}
+	return expm1(x)
+}
+
+func expm1(x float64) float64 {
+	const (
+		Othreshold = 7.09782712893383973096e+02 // 0x40862E42FEFA39EF
+		Ln2X56     = 3.88162421113569373274e+01 // 0x4043687a9f1af2b1
+		Ln2HalfX3  = 1.03972077083991796413e+00 // 0x3ff0a2b23f3bab73
+		Ln2Half    = 3.46573590279972654709e-01 // 0x3fd62e42fefa39ef
+		Ln2Hi      = 6.93147180369123816490e-01 // 0x3fe62e42fee00000
+		Ln2Lo      = 1.90821492927058770002e-10 // 0x3dea39ef35793c76
+		InvLn2     = 1.44269504088896338700e+00 // 0x3ff71547652b82fe
+		Tiny       = 1.0 / (1 << 54)            // 2**-54 = 0x3c90000000000000
+		// scaled coefficients related to expm1
+		Q1 = -3.33333333333331316428e-02 // 0xBFA11111111110F4
+		Q2 = 1.58730158725481460165e-03  // 0x3F5A01A019FE5585
+		Q3 = -7.93650757867487942473e-05 // 0xBF14CE199EAADBB7
+		Q4 = 4.00821782732936239552e-06  // 0x3ED0CFCA86E65239
+		Q5 = -2.01099218183624371326e-07 // 0xBE8AFDB76E09C32D
+	)
+
+	// special cases
+	switch {
+	case IsInf(x, 1) || IsNaN(x):
+		return x
+	case IsInf(x, -1):
+		return -1
+	}
+
+	absx := x
+	sign := false
+	if x < 0 {
+		absx = -absx
+		sign = true
+	}
+
+	// filter out huge argument
+	if absx >= Ln2X56 { // if |x| >= 56 * ln2
+		if sign {
+			return -1 // x < -56*ln2, return -1
+		}
+		if absx >= Othreshold { // if |x| >= 709.78...
+			return Inf(1)
+		}
+	}
+
+	// argument reduction
+	var c float64
+	var k int
+	if absx > Ln2Half { // if  |x| > 0.5 * ln2
+		var hi, lo float64
+		if absx < Ln2HalfX3 { // and |x| < 1.5 * ln2
+			if !sign {
+				hi = x - Ln2Hi
+				lo = Ln2Lo
+				k = 1
+			} else {
+				hi = x + Ln2Hi
+				lo = -Ln2Lo
+				k = -1
+			}
+		} else {
+			if !sign {
+				k = int(InvLn2*x + 0.5)
+			} else {
+				k = int(InvLn2*x - 0.5)
+			}
+			t := float64(k)
+			hi = x - t*Ln2Hi // t * Ln2Hi is exact here
+			lo = t * Ln2Lo
+		}
+		x = hi - lo
+		c = (hi - x) - lo
+	} else if absx < Tiny { // when |x| < 2**-54, return x
+		return x
+	} else {
+		k = 0
+	}
+
+	// x is now in primary range
+	hfx := 0.5 * x
+	hxs := x * hfx
+	r1 := 1 + hxs*(Q1+hxs*(Q2+hxs*(Q3+hxs*(Q4+hxs*Q5))))
+	t := 3 - r1*hfx
+	e := hxs * ((r1 - t) / (6.0 - x*t))
+	if k == 0 {
+		return x - (x*e - hxs) // c is 0
+	}
+	e = (x*(e-c) - c)
+	e -= hxs
+	switch {
+	case k == -1:
+		return 0.5*(x-e) - 0.5
+	case k == 1:
+		if x < -0.25 {
+			return -2 * (e - (x + 0.5))
+		}
+		return 1 + 2*(x-e)
+	case k <= -2 || k > 56: // suffice to return exp(x)-1
+		y := 1 - (e - x)
+		y = Float64frombits(Float64bits(y) + uint64(k)<<52) // add k to y's exponent
+		return y - 1
+	}
+	if k < 20 {
+		t := Float64frombits(0x3ff0000000000000 - (0x20000000000000 >> uint(k))) // t=1-2**-k
+		y := t - (e - x)
+		y = Float64frombits(Float64bits(y) + uint64(k)<<52) // add k to y's exponent
+		return y
+	}
+	t = Float64frombits(uint64(0x3ff-k) << 52) // 2**-k
+	y := x - (e + t)
+	y++
+	y = Float64frombits(Float64bits(y) + uint64(k)<<52) // add k to y's exponent
+	return y
+}
diff --git a/contrib/go/_std_1.19/src/math/floor.go b/contrib/go/_std_1.19/src/math/floor.go
new file mode 100644
index 0000000000..cb5856424b
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/floor.go
@@ -0,0 +1,151 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Floor returns the greatest integer value less than or equal to x.
+//
+// Special cases are:
+//
+//	Floor(±0) = ±0
+//	Floor(±Inf) = ±Inf
+//	Floor(NaN) = NaN
+func Floor(x float64) float64 {
+	if haveArchFloor {
+		return archFloor(x)
+	}
+	return floor(x)
+}
+
+func floor(x float64) float64 {
+	if x == 0 || IsNaN(x) || IsInf(x, 0) {
+		return x
+	}
+	if x < 0 {
+		d, fract := Modf(-x)
+		if fract != 0.0 {
+			d = d + 1
+		}
+		return -d
+	}
+	d, _ := Modf(x)
+	return d
+}
+
+// Ceil returns the least integer value greater than or equal to x.
+//
+// Special cases are:
+//
+//	Ceil(±0) = ±0
+//	Ceil(±Inf) = ±Inf
+//	Ceil(NaN) = NaN
+func Ceil(x float64) float64 {
+	if haveArchCeil {
+		return archCeil(x)
+	}
+	return ceil(x)
+}
+
+func ceil(x float64) float64 {
+	return -Floor(-x)
+}
+
+// Trunc returns the integer value of x.
+//
+// Special cases are:
+//
+//	Trunc(±0) = ±0
+//	Trunc(±Inf) = ±Inf
+//	Trunc(NaN) = NaN
+func Trunc(x float64) float64 {
+	if haveArchTrunc {
+		return archTrunc(x)
+	}
+	return trunc(x)
+}
+
+func trunc(x float64) float64 {
+	if x == 0 || IsNaN(x) || IsInf(x, 0) {
+		return x
+	}
+	d, _ := Modf(x)
+	return d
+}
+
+// Round returns the nearest integer, rounding half away from zero.
+//
+// Special cases are:
+//
+//	Round(±0) = ±0
+//	Round(±Inf) = ±Inf
+//	Round(NaN) = NaN
+func Round(x float64) float64 {
+	// Round is a faster implementation of:
+	//
+	// func Round(x float64) float64 {
+	//   t := Trunc(x)
+	//   if Abs(x-t) >= 0.5 {
+	//     return t + Copysign(1, x)
+	//   }
+	//   return t
+	// }
+	bits := Float64bits(x)
+	e := uint(bits>>shift) & mask
+	if e < bias {
+		// Round abs(x) < 1 including denormals.
+		bits &= signMask // +-0
+		if e == bias-1 {
+			bits |= uvone // +-1
+		}
+	} else if e < bias+shift {
+		// Round any abs(x) >= 1 containing a fractional component [0,1).
+		//
+		// Numbers with larger exponents are returned unchanged since they
+		// must be either an integer, infinity, or NaN.
+		const half = 1 << (shift - 1)
+		e -= bias
+		bits += half >> e
+		bits &^= fracMask >> e
+	}
+	return Float64frombits(bits)
+}
+
+// RoundToEven returns the nearest integer, rounding ties to even.
+//
+// Special cases are:
+//
+//	RoundToEven(±0) = ±0
+//	RoundToEven(±Inf) = ±Inf
+//	RoundToEven(NaN) = NaN
+func RoundToEven(x float64) float64 {
+	// RoundToEven is a faster implementation of:
+	//
+	// func RoundToEven(x float64) float64 {
+	//   t := math.Trunc(x)
+	//   odd := math.Remainder(t, 2) != 0
+	//   if d := math.Abs(x - t); d > 0.5 || (d == 0.5 && odd) {
+	//     return t + math.Copysign(1, x)
+	//   }
+	//   return t
+	// }
+	bits := Float64bits(x)
+	e := uint(bits>>shift) & mask
+	if e >= bias {
+		// Round abs(x) >= 1.
+		// - Large numbers without fractional components, infinity, and NaN are unchanged.
+		// - Add 0.499.. or 0.5 before truncating depending on whether the truncated
+		//   number is even or odd (respectively).
+		const halfMinusULP = (1 << (shift - 1)) - 1
+		e -= bias
+		bits += (halfMinusULP + (bits>>(shift-e))&1) >> e
+		bits &^= fracMask >> e
+	} else if e == bias-1 && bits&fracMask != 0 {
+		// Round 0.5 < abs(x) < 1.
+		bits = bits&signMask | uvone // +-1
+	} else {
+		// Round abs(x) <= 0.5 including denormals.
+		bits &= signMask // +-0
+	}
+	return Float64frombits(bits)
+}
diff --git a/contrib/go/_std_1.18/src/math/floor_amd64.s b/contrib/go/_std_1.19/src/math/floor_amd64.s
index 088049958a..088049958a 100644
--- a/contrib/go/_std_1.18/src/math/floor_amd64.s
+++ b/contrib/go/_std_1.19/src/math/floor_amd64.s
diff --git a/contrib/go/_std_1.18/src/math/floor_asm.go b/contrib/go/_std_1.19/src/math/floor_asm.go
index fb419d6da2..fb419d6da2 100644
--- a/contrib/go/_std_1.18/src/math/floor_asm.go
+++ b/contrib/go/_std_1.19/src/math/floor_asm.go
diff --git a/contrib/go/_std_1.18/src/math/fma.go b/contrib/go/_std_1.19/src/math/fma.go
index ca0bf99f21..ca0bf99f21 100644
--- a/contrib/go/_std_1.18/src/math/fma.go
+++ b/contrib/go/_std_1.19/src/math/fma.go
diff --git a/contrib/go/_std_1.19/src/math/frexp.go b/contrib/go/_std_1.19/src/math/frexp.go
new file mode 100644
index 0000000000..e194947e64
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/frexp.go
@@ -0,0 +1,39 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Frexp breaks f into a normalized fraction
+// and an integral power of two.
+// It returns frac and exp satisfying f == frac × 2**exp,
+// with the absolute value of frac in the interval [½, 1).
+//
+// Special cases are:
+//
+//	Frexp(±0) = ±0, 0
+//	Frexp(±Inf) = ±Inf, 0
+//	Frexp(NaN) = NaN, 0
+func Frexp(f float64) (frac float64, exp int) {
+	if haveArchFrexp {
+		return archFrexp(f)
+	}
+	return frexp(f)
+}
+
+func frexp(f float64) (frac float64, exp int) {
+	// special cases
+	switch {
+	case f == 0:
+		return f, 0 // correctly return -0
+	case IsInf(f, 0) || IsNaN(f):
+		return f, 0
+	}
+	f, exp = normalize(f)
+	x := Float64bits(f)
+	exp += int((x>>shift)&mask) - bias + 1
+	x &^= mask << shift
+	x |= (-1 + bias) << shift
+	frac = Float64frombits(x)
+	return
+}
diff --git a/contrib/go/_std_1.19/src/math/gamma.go b/contrib/go/_std_1.19/src/math/gamma.go
new file mode 100644
index 0000000000..86c6723258
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/gamma.go
@@ -0,0 +1,222 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// The original C code, the long comment, and the constants
+// below are from http://netlib.sandia.gov/cephes/cprob/gamma.c.
+// The go code is a simplified version of the original C.
+//
+//      tgamma.c
+//
+//      Gamma function
+//
+// SYNOPSIS:
+//
+// double x, y, tgamma();
+// extern int signgam;
+//
+// y = tgamma( x );
+//
+// DESCRIPTION:
+//
+// Returns gamma function of the argument. The result is
+// correctly signed, and the sign (+1 or -1) is also
+// returned in a global (extern) variable named signgam.
+// This variable is also filled in by the logarithmic gamma
+// function lgamma().
+//
+// Arguments |x| <= 34 are reduced by recurrence and the function
+// approximated by a rational function of degree 6/7 in the
+// interval (2,3).  Large arguments are handled by Stirling's
+// formula. Large negative arguments are made positive using
+// a reflection formula.
+//
+// ACCURACY:
+//
+//                      Relative error:
+// arithmetic   domain     # trials      peak         rms
+//    DEC      -34, 34      10000       1.3e-16     2.5e-17
+//    IEEE    -170,-33      20000       2.3e-15     3.3e-16
+//    IEEE     -33,  33     20000       9.4e-16     2.2e-16
+//    IEEE      33, 171.6   20000       2.3e-15     3.2e-16
+//
+// Error for arguments outside the test range will be larger
+// owing to error amplification by the exponential function.
+//
+// Cephes Math Library Release 2.8:  June, 2000
+// Copyright 1984, 1987, 1989, 1992, 2000 by Stephen L. Moshier
+//
+// The readme file at http://netlib.sandia.gov/cephes/ says:
+//    Some software in this archive may be from the book _Methods and
+// Programs for Mathematical Functions_ (Prentice-Hall or Simon & Schuster
+// International, 1989) or from the Cephes Mathematical Library, a
+// commercial product. In either event, it is copyrighted by the author.
+// What you see here may be used freely but it comes with no support or
+// guarantee.
+//
+//   The two known misprints in the book are repaired here in the
+// source listings for the gamma function and the incomplete beta
+// integral.
+//
+//   Stephen L. Moshier
+//   moshier@na-net.ornl.gov
+
+var _gamP = [...]float64{
+	1.60119522476751861407e-04,
+	1.19135147006586384913e-03,
+	1.04213797561761569935e-02,
+	4.76367800457137231464e-02,
+	2.07448227648435975150e-01,
+	4.94214826801497100753e-01,
+	9.99999999999999996796e-01,
+}
+var _gamQ = [...]float64{
+	-2.31581873324120129819e-05,
+	5.39605580493303397842e-04,
+	-4.45641913851797240494e-03,
+	1.18139785222060435552e-02,
+	3.58236398605498653373e-02,
+	-2.34591795718243348568e-01,
+	7.14304917030273074085e-02,
+	1.00000000000000000320e+00,
+}
+var _gamS = [...]float64{
+	7.87311395793093628397e-04,
+	-2.29549961613378126380e-04,
+	-2.68132617805781232825e-03,
+	3.47222221605458667310e-03,
+	8.33333333333482257126e-02,
+}
+
+// Gamma function computed by Stirling's formula.
+// The pair of results must be multiplied together to get the actual answer.
+// The multiplication is left to the caller so that, if careful, the caller can avoid
+// infinity for 172 <= x <= 180.
+// The polynomial is valid for 33 <= x <= 172; larger values are only used
+// in reciprocal and produce denormalized floats. The lower precision there
+// masks any imprecision in the polynomial.
+func stirling(x float64) (float64, float64) {
+	if x > 200 {
+		return Inf(1), 1
+	}
+	const (
+		SqrtTwoPi   = 2.506628274631000502417
+		MaxStirling = 143.01608
+	)
+	w := 1 / x
+	w = 1 + w*((((_gamS[0]*w+_gamS[1])*w+_gamS[2])*w+_gamS[3])*w+_gamS[4])
+	y1 := Exp(x)
+	y2 := 1.0
+	if x > MaxStirling { // avoid Pow() overflow
+		v := Pow(x, 0.5*x-0.25)
+		y1, y2 = v, v/y1
+	} else {
+		y1 = Pow(x, x-0.5) / y1
+	}
+	return y1, SqrtTwoPi * w * y2
+}
+
+// Gamma returns the Gamma function of x.
+//
+// Special cases are:
+//
+//	Gamma(+Inf) = +Inf
+//	Gamma(+0) = +Inf
+//	Gamma(-0) = -Inf
+//	Gamma(x) = NaN for integer x < 0
+//	Gamma(-Inf) = NaN
+//	Gamma(NaN) = NaN
+func Gamma(x float64) float64 {
+	const Euler = 0.57721566490153286060651209008240243104215933593992 // A001620
+	// special cases
+	switch {
+	case isNegInt(x) || IsInf(x, -1) || IsNaN(x):
+		return NaN()
+	case IsInf(x, 1):
+		return Inf(1)
+	case x == 0:
+		if Signbit(x) {
+			return Inf(-1)
+		}
+		return Inf(1)
+	}
+	q := Abs(x)
+	p := Floor(q)
+	if q > 33 {
+		if x >= 0 {
+			y1, y2 := stirling(x)
+			return y1 * y2
+		}
+		// Note: x is negative but (checked above) not a negative integer,
+		// so x must be small enough to be in range for conversion to int64.
+		// If |x| were >= 2⁶³ it would have to be an integer.
+		signgam := 1
+		if ip := int64(p); ip&1 == 0 {
+			signgam = -1
+		}
+		z := q - p
+		if z > 0.5 {
+			p = p + 1
+			z = q - p
+		}
+		z = q * Sin(Pi*z)
+		if z == 0 {
+			return Inf(signgam)
+		}
+		sq1, sq2 := stirling(q)
+		absz := Abs(z)
+		d := absz * sq1 * sq2
+		if IsInf(d, 0) {
+			z = Pi / absz / sq1 / sq2
+		} else {
+			z = Pi / d
+		}
+		return float64(signgam) * z
+	}
+
+	// Reduce argument
+	z := 1.0
+	for x >= 3 {
+		x = x - 1
+		z = z * x
+	}
+	for x < 0 {
+		if x > -1e-09 {
+			goto small
+		}
+		z = z / x
+		x = x + 1
+	}
+	for x < 2 {
+		if x < 1e-09 {
+			goto small
+		}
+		z = z / x
+		x = x + 1
+	}
+
+	if x == 2 {
+		return z
+	}
+
+	x = x - 2
+	p = (((((x*_gamP[0]+_gamP[1])*x+_gamP[2])*x+_gamP[3])*x+_gamP[4])*x+_gamP[5])*x + _gamP[6]
+	q = ((((((x*_gamQ[0]+_gamQ[1])*x+_gamQ[2])*x+_gamQ[3])*x+_gamQ[4])*x+_gamQ[5])*x+_gamQ[6])*x + _gamQ[7]
+	return z * p / q
+
+small:
+	if x == 0 {
+		return Inf(1)
+	}
+	return z / ((1 + Euler*x) * x)
+}
+
+func isNegInt(x float64) bool {
+	if x < 0 {
+		_, xf := Modf(x)
+		return xf == 0
+	}
+	return false
+}
diff --git a/contrib/go/_std_1.19/src/math/hypot.go b/contrib/go/_std_1.19/src/math/hypot.go
new file mode 100644
index 0000000000..4e79de0e9b
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/hypot.go
@@ -0,0 +1,44 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+	Hypot -- sqrt(p*p + q*q), but overflows only if the result does.
+*/
+
+// Hypot returns Sqrt(p*p + q*q), taking care to avoid
+// unnecessary overflow and underflow.
+//
+// Special cases are:
+//
+//	Hypot(±Inf, q) = +Inf
+//	Hypot(p, ±Inf) = +Inf
+//	Hypot(NaN, q) = NaN
+//	Hypot(p, NaN) = NaN
+func Hypot(p, q float64) float64 {
+	if haveArchHypot {
+		return archHypot(p, q)
+	}
+	return hypot(p, q)
+}
+
+func hypot(p, q float64) float64 {
+	// special cases
+	switch {
+	case IsInf(p, 0) || IsInf(q, 0):
+		return Inf(1)
+	case IsNaN(p) || IsNaN(q):
+		return NaN()
+	}
+	p, q = Abs(p), Abs(q)
+	if p < q {
+		p, q = q, p
+	}
+	if p == 0 {
+		return 0
+	}
+	q = q / p
+	return p * Sqrt(1+q*q)
+}
diff --git a/contrib/go/_std_1.18/src/math/hypot_amd64.s b/contrib/go/_std_1.19/src/math/hypot_amd64.s
index fe326c9281..fe326c9281 100644
--- a/contrib/go/_std_1.18/src/math/hypot_amd64.s
+++ b/contrib/go/_std_1.19/src/math/hypot_amd64.s
diff --git a/contrib/go/_std_1.18/src/math/hypot_asm.go b/contrib/go/_std_1.19/src/math/hypot_asm.go
index 852691037f..852691037f 100644
--- a/contrib/go/_std_1.18/src/math/hypot_asm.go
+++ b/contrib/go/_std_1.19/src/math/hypot_asm.go
diff --git a/contrib/go/_std_1.19/src/math/j0.go b/contrib/go/_std_1.19/src/math/j0.go
new file mode 100644
index 0000000000..a311e18d62
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/j0.go
@@ -0,0 +1,429 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+	Bessel function of the first and second kinds of order zero.
+*/
+
+// The original C code and the long comment below are
+// from FreeBSD's /usr/src/lib/msun/src/e_j0.c and
+// came with this notice. The go code is a simplified
+// version of the original C.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+// __ieee754_j0(x), __ieee754_y0(x)
+// Bessel function of the first and second kinds of order zero.
+// Method -- j0(x):
+//      1. For tiny x, we use j0(x) = 1 - x**2/4 + x**4/64 - ...
+//      2. Reduce x to |x| since j0(x)=j0(-x),  and
+//         for x in (0,2)
+//              j0(x) = 1-z/4+ z**2*R0/S0,  where z = x*x;
+//         (precision:  |j0-1+z/4-z**2R0/S0 |<2**-63.67 )
+//         for x in (2,inf)
+//              j0(x) = sqrt(2/(pi*x))*(p0(x)*cos(x0)-q0(x)*sin(x0))
+//         where x0 = x-pi/4. It is better to compute sin(x0),cos(x0)
+//         as follow:
+//              cos(x0) = cos(x)cos(pi/4)+sin(x)sin(pi/4)
+//                      = 1/sqrt(2) * (cos(x) + sin(x))
+//              sin(x0) = sin(x)cos(pi/4)-cos(x)sin(pi/4)
+//                      = 1/sqrt(2) * (sin(x) - cos(x))
+//         (To avoid cancellation, use
+//              sin(x) +- cos(x) = -cos(2x)/(sin(x) -+ cos(x))
+//         to compute the worse one.)
+//
+//      3 Special cases
+//              j0(nan)= nan
+//              j0(0) = 1
+//              j0(inf) = 0
+//
+// Method -- y0(x):
+//      1. For x<2.
+//         Since
+//              y0(x) = 2/pi*(j0(x)*(ln(x/2)+Euler) + x**2/4 - ...)
+//         therefore y0(x)-2/pi*j0(x)*ln(x) is an even function.
+//         We use the following function to approximate y0,
+//              y0(x) = U(z)/V(z) + (2/pi)*(j0(x)*ln(x)), z= x**2
+//         where
+//              U(z) = u00 + u01*z + ... + u06*z**6
+//              V(z) = 1  + v01*z + ... + v04*z**4
+//         with absolute approximation error bounded by 2**-72.
+//         Note: For tiny x, U/V = u0 and j0(x)~1, hence
+//              y0(tiny) = u0 + (2/pi)*ln(tiny), (choose tiny<2**-27)
+//      2. For x>=2.
+//              y0(x) = sqrt(2/(pi*x))*(p0(x)*cos(x0)+q0(x)*sin(x0))
+//         where x0 = x-pi/4. It is better to compute sin(x0),cos(x0)
+//         by the method mentioned above.
+//      3. Special cases: y0(0)=-inf, y0(x<0)=NaN, y0(inf)=0.
+//
+
+// J0 returns the order-zero Bessel function of the first kind.
+//
+// Special cases are:
+//
+//	J0(±Inf) = 0
+//	J0(0) = 1
+//	J0(NaN) = NaN
+func J0(x float64) float64 {
+	const (
+		Huge   = 1e300
+		TwoM27 = 1.0 / (1 << 27) // 2**-27 0x3e40000000000000
+		TwoM13 = 1.0 / (1 << 13) // 2**-13 0x3f20000000000000
+		Two129 = 1 << 129        // 2**129 0x4800000000000000
+		// R0/S0 on [0, 2]
+		R02 = 1.56249999999999947958e-02  // 0x3F8FFFFFFFFFFFFD
+		R03 = -1.89979294238854721751e-04 // 0xBF28E6A5B61AC6E9
+		R04 = 1.82954049532700665670e-06  // 0x3EBEB1D10C503919
+		R05 = -4.61832688532103189199e-09 // 0xBE33D5E773D63FCE
+		S01 = 1.56191029464890010492e-02  // 0x3F8FFCE882C8C2A4
+		S02 = 1.16926784663337450260e-04  // 0x3F1EA6D2DD57DBF4
+		S03 = 5.13546550207318111446e-07  // 0x3EA13B54CE84D5A9
+		S04 = 1.16614003333790000205e-09  // 0x3E1408BCF4745D8F
+	)
+	// special cases
+	switch {
+	case IsNaN(x):
+		return x
+	case IsInf(x, 0):
+		return 0
+	case x == 0:
+		return 1
+	}
+
+	x = Abs(x)
+	if x >= 2 {
+		s, c := Sincos(x)
+		ss := s - c
+		cc := s + c
+
+		// make sure x+x does not overflow
+		if x < MaxFloat64/2 {
+			z := -Cos(x + x)
+			if s*c < 0 {
+				cc = z / ss
+			} else {
+				ss = z / cc
+			}
+		}
+
+		// j0(x) = 1/sqrt(pi) * (P(0,x)*cc - Q(0,x)*ss) / sqrt(x)
+		// y0(x) = 1/sqrt(pi) * (P(0,x)*ss + Q(0,x)*cc) / sqrt(x)
+
+		var z float64
+		if x > Two129 { // |x| > ~6.8056e+38
+			z = (1 / SqrtPi) * cc / Sqrt(x)
+		} else {
+			u := pzero(x)
+			v := qzero(x)
+			z = (1 / SqrtPi) * (u*cc - v*ss) / Sqrt(x)
+		}
+		return z // |x| >= 2.0
+	}
+	if x < TwoM13 { // |x| < ~1.2207e-4
+		if x < TwoM27 {
+			return 1 // |x| < ~7.4506e-9
+		}
+		return 1 - 0.25*x*x // ~7.4506e-9 < |x| < ~1.2207e-4
+	}
+	z := x * x
+	r := z * (R02 + z*(R03+z*(R04+z*R05)))
+	s := 1 + z*(S01+z*(S02+z*(S03+z*S04)))
+	if x < 1 {
+		return 1 + z*(-0.25+(r/s)) // |x| < 1.00
+	}
+	u := 0.5 * x
+	return (1+u)*(1-u) + z*(r/s) // 1.0 < |x| < 2.0
+}
+
+// Y0 returns the order-zero Bessel function of the second kind.
+//
+// Special cases are:
+//
+//	Y0(+Inf) = 0
+//	Y0(0) = -Inf
+//	Y0(x < 0) = NaN
+//	Y0(NaN) = NaN
+func Y0(x float64) float64 {
+	const (
+		TwoM27 = 1.0 / (1 << 27)             // 2**-27 0x3e40000000000000
+		Two129 = 1 << 129                    // 2**129 0x4800000000000000
+		U00    = -7.38042951086872317523e-02 // 0xBFB2E4D699CBD01F
+		U01    = 1.76666452509181115538e-01  // 0x3FC69D019DE9E3FC
+		U02    = -1.38185671945596898896e-02 // 0xBF8C4CE8B16CFA97
+		U03    = 3.47453432093683650238e-04  // 0x3F36C54D20B29B6B
+		U04    = -3.81407053724364161125e-06 // 0xBECFFEA773D25CAD
+		U05    = 1.95590137035022920206e-08  // 0x3E5500573B4EABD4
+		U06    = -3.98205194132103398453e-11 // 0xBDC5E43D693FB3C8
+		V01    = 1.27304834834123699328e-02  // 0x3F8A127091C9C71A
+		V02    = 7.60068627350353253702e-05  // 0x3F13ECBBF578C6C1
+		V03    = 2.59150851840457805467e-07  // 0x3E91642D7FF202FD
+		V04    = 4.41110311332675467403e-10  // 0x3DFE50183BD6D9EF
+	)
+	// special cases
+	switch {
+	case x < 0 || IsNaN(x):
+		return NaN()
+	case IsInf(x, 1):
+		return 0
+	case x == 0:
+		return Inf(-1)
+	}
+
+	if x >= 2 { // |x| >= 2.0
+
+		// y0(x) = sqrt(2/(pi*x))*(p0(x)*sin(x0)+q0(x)*cos(x0))
+		//     where x0 = x-pi/4
+		// Better formula:
+		//     cos(x0) = cos(x)cos(pi/4)+sin(x)sin(pi/4)
+		//             =  1/sqrt(2) * (sin(x) + cos(x))
+		//     sin(x0) = sin(x)cos(3pi/4)-cos(x)sin(3pi/4)
+		//             =  1/sqrt(2) * (sin(x) - cos(x))
+		// To avoid cancellation, use
+		//     sin(x) +- cos(x) = -cos(2x)/(sin(x) -+ cos(x))
+		// to compute the worse one.
+
+		s, c := Sincos(x)
+		ss := s - c
+		cc := s + c
+
+		// j0(x) = 1/sqrt(pi) * (P(0,x)*cc - Q(0,x)*ss) / sqrt(x)
+		// y0(x) = 1/sqrt(pi) * (P(0,x)*ss + Q(0,x)*cc) / sqrt(x)
+
+		// make sure x+x does not overflow
+		if x < MaxFloat64/2 {
+			z := -Cos(x + x)
+			if s*c < 0 {
+				cc = z / ss
+			} else {
+				ss = z / cc
+			}
+		}
+		var z float64
+		if x > Two129 { // |x| > ~6.8056e+38
+			z = (1 / SqrtPi) * ss / Sqrt(x)
+		} else {
+			u := pzero(x)
+			v := qzero(x)
+			z = (1 / SqrtPi) * (u*ss + v*cc) / Sqrt(x)
+		}
+		return z // |x| >= 2.0
+	}
+	if x <= TwoM27 {
+		return U00 + (2/Pi)*Log(x) // |x| < ~7.4506e-9
+	}
+	z := x * x
+	u := U00 + z*(U01+z*(U02+z*(U03+z*(U04+z*(U05+z*U06)))))
+	v := 1 + z*(V01+z*(V02+z*(V03+z*V04)))
+	return u/v + (2/Pi)*J0(x)*Log(x) // ~7.4506e-9 < |x| < 2.0
+}
+
+// The asymptotic expansions of pzero is
+//      1 - 9/128 s**2 + 11025/98304 s**4 - ..., where s = 1/x.
+// For x >= 2, We approximate pzero by
+// 	pzero(x) = 1 + (R/S)
+// where  R = pR0 + pR1*s**2 + pR2*s**4 + ... + pR5*s**10
+// 	  S = 1 + pS0*s**2 + ... + pS4*s**10
+// and
+//      | pzero(x)-1-R/S | <= 2  ** ( -60.26)
+
+// for x in [inf, 8]=1/[0,0.125]
+var p0R8 = [6]float64{
+	0.00000000000000000000e+00,  // 0x0000000000000000
+	-7.03124999999900357484e-02, // 0xBFB1FFFFFFFFFD32
+	-8.08167041275349795626e+00, // 0xC02029D0B44FA779
+	-2.57063105679704847262e+02, // 0xC07011027B19E863
+	-2.48521641009428822144e+03, // 0xC0A36A6ECD4DCAFC
+	-5.25304380490729545272e+03, // 0xC0B4850B36CC643D
+}
+var p0S8 = [5]float64{
+	1.16534364619668181717e+02, // 0x405D223307A96751
+	3.83374475364121826715e+03, // 0x40ADF37D50596938
+	4.05978572648472545552e+04, // 0x40E3D2BB6EB6B05F
+	1.16752972564375915681e+05, // 0x40FC810F8F9FA9BD
+	4.76277284146730962675e+04, // 0x40E741774F2C49DC
+}
+
+// for x in [8,4.5454]=1/[0.125,0.22001]
+var p0R5 = [6]float64{
+	-1.14125464691894502584e-11, // 0xBDA918B147E495CC
+	-7.03124940873599280078e-02, // 0xBFB1FFFFE69AFBC6
+	-4.15961064470587782438e+00, // 0xC010A370F90C6BBF
+	-6.76747652265167261021e+01, // 0xC050EB2F5A7D1783
+	-3.31231299649172967747e+02, // 0xC074B3B36742CC63
+	-3.46433388365604912451e+02, // 0xC075A6EF28A38BD7
+}
+var p0S5 = [5]float64{
+	6.07539382692300335975e+01, // 0x404E60810C98C5DE
+	1.05125230595704579173e+03, // 0x40906D025C7E2864
+	5.97897094333855784498e+03, // 0x40B75AF88FBE1D60
+	9.62544514357774460223e+03, // 0x40C2CCB8FA76FA38
+	2.40605815922939109441e+03, // 0x40A2CC1DC70BE864
+}
+
+// for x in [4.547,2.8571]=1/[0.2199,0.35001]
+var p0R3 = [6]float64{
+	-2.54704601771951915620e-09, // 0xBE25E1036FE1AA86
+	-7.03119616381481654654e-02, // 0xBFB1FFF6F7C0E24B
+	-2.40903221549529611423e+00, // 0xC00345B2AEA48074
+	-2.19659774734883086467e+01, // 0xC035F74A4CB94E14
+	-5.80791704701737572236e+01, // 0xC04D0A22420A1A45
+	-3.14479470594888503854e+01, // 0xC03F72ACA892D80F
+}
+var p0S3 = [5]float64{
+	3.58560338055209726349e+01, // 0x4041ED9284077DD3
+	3.61513983050303863820e+02, // 0x40769839464A7C0E
+	1.19360783792111533330e+03, // 0x4092A66E6D1061D6
+	1.12799679856907414432e+03, // 0x40919FFCB8C39B7E
+	1.73580930813335754692e+02, // 0x4065B296FC379081
+}
+
+// for x in [2.8570,2]=1/[0.3499,0.5]
+var p0R2 = [6]float64{
+	-8.87534333032526411254e-08, // 0xBE77D316E927026D
+	-7.03030995483624743247e-02, // 0xBFB1FF62495E1E42
+	-1.45073846780952986357e+00, // 0xBFF736398A24A843
+	-7.63569613823527770791e+00, // 0xC01E8AF3EDAFA7F3
+	-1.11931668860356747786e+01, // 0xC02662E6C5246303
+	-3.23364579351335335033e+00, // 0xC009DE81AF8FE70F
+}
+var p0S2 = [5]float64{
+	2.22202997532088808441e+01, // 0x40363865908B5959
+	1.36206794218215208048e+02, // 0x4061069E0EE8878F
+	2.70470278658083486789e+02, // 0x4070E78642EA079B
+	1.53875394208320329881e+02, // 0x40633C033AB6FAFF
+	1.46576176948256193810e+01, // 0x402D50B344391809
+}
+
+func pzero(x float64) float64 {
+	var p *[6]float64
+	var q *[5]float64
+	if x >= 8 {
+		p = &p0R8
+		q = &p0S8
+	} else if x >= 4.5454 {
+		p = &p0R5
+		q = &p0S5
+	} else if x >= 2.8571 {
+		p = &p0R3
+		q = &p0S3
+	} else if x >= 2 {
+		p = &p0R2
+		q = &p0S2
+	}
+	z := 1 / (x * x)
+	r := p[0] + z*(p[1]+z*(p[2]+z*(p[3]+z*(p[4]+z*p[5]))))
+	s := 1 + z*(q[0]+z*(q[1]+z*(q[2]+z*(q[3]+z*q[4]))))
+	return 1 + r/s
+}
+
+// For x >= 8, the asymptotic expansions of qzero is
+//      -1/8 s + 75/1024 s**3 - ..., where s = 1/x.
+// We approximate pzero by
+//      qzero(x) = s*(-1.25 + (R/S))
+// where R = qR0 + qR1*s**2 + qR2*s**4 + ... + qR5*s**10
+//       S = 1 + qS0*s**2 + ... + qS5*s**12
+// and
+//      | qzero(x)/s +1.25-R/S | <= 2**(-61.22)
+
+// for x in [inf, 8]=1/[0,0.125]
+var q0R8 = [6]float64{
+	0.00000000000000000000e+00, // 0x0000000000000000
+	7.32421874999935051953e-02, // 0x3FB2BFFFFFFFFE2C
+	1.17682064682252693899e+01, // 0x402789525BB334D6
+	5.57673380256401856059e+02, // 0x40816D6315301825
+	8.85919720756468632317e+03, // 0x40C14D993E18F46D
+	3.70146267776887834771e+04, // 0x40E212D40E901566
+}
+var q0S8 = [6]float64{
+	1.63776026895689824414e+02,  // 0x406478D5365B39BC
+	8.09834494656449805916e+03,  // 0x40BFA2584E6B0563
+	1.42538291419120476348e+05,  // 0x4101665254D38C3F
+	8.03309257119514397345e+05,  // 0x412883DA83A52B43
+	8.40501579819060512818e+05,  // 0x4129A66B28DE0B3D
+	-3.43899293537866615225e+05, // 0xC114FD6D2C9530C5
+}
+
+// for x in [8,4.5454]=1/[0.125,0.22001]
+var q0R5 = [6]float64{
+	1.84085963594515531381e-11, // 0x3DB43D8F29CC8CD9
+	7.32421766612684765896e-02, // 0x3FB2BFFFD172B04C
+	5.83563508962056953777e+00, // 0x401757B0B9953DD3
+	1.35111577286449829671e+02, // 0x4060E3920A8788E9
+	1.02724376596164097464e+03, // 0x40900CF99DC8C481
+	1.98997785864605384631e+03, // 0x409F17E953C6E3A6
+}
+var q0S5 = [6]float64{
+	8.27766102236537761883e+01,  // 0x4054B1B3FB5E1543
+	2.07781416421392987104e+03,  // 0x40A03BA0DA21C0CE
+	1.88472887785718085070e+04,  // 0x40D267D27B591E6D
+	5.67511122894947329769e+04,  // 0x40EBB5E397E02372
+	3.59767538425114471465e+04,  // 0x40E191181F7A54A0
+	-5.35434275601944773371e+03, // 0xC0B4EA57BEDBC609
+}
+
+// for x in [4.547,2.8571]=1/[0.2199,0.35001]
+var q0R3 = [6]float64{
+	4.37741014089738620906e-09, // 0x3E32CD036ADECB82
+	7.32411180042911447163e-02, // 0x3FB2BFEE0E8D0842
+	3.34423137516170720929e+00, // 0x400AC0FC61149CF5
+	4.26218440745412650017e+01, // 0x40454F98962DAEDD
+	1.70808091340565596283e+02, // 0x406559DBE25EFD1F
+	1.66733948696651168575e+02, // 0x4064D77C81FA21E0
+}
+var q0S3 = [6]float64{
+	4.87588729724587182091e+01,  // 0x40486122BFE343A6
+	7.09689221056606015736e+02,  // 0x40862D8386544EB3
+	3.70414822620111362994e+03,  // 0x40ACF04BE44DFC63
+	6.46042516752568917582e+03,  // 0x40B93C6CD7C76A28
+	2.51633368920368957333e+03,  // 0x40A3A8AAD94FB1C0
+	-1.49247451836156386662e+02, // 0xC062A7EB201CF40F
+}
+
+// for x in [2.8570,2]=1/[0.3499,0.5]
+var q0R2 = [6]float64{
+	1.50444444886983272379e-07, // 0x3E84313B54F76BDB
+	7.32234265963079278272e-02, // 0x3FB2BEC53E883E34
+	1.99819174093815998816e+00, // 0x3FFFF897E727779C
+	1.44956029347885735348e+01, // 0x402CFDBFAAF96FE5
+	3.16662317504781540833e+01, // 0x403FAA8E29FBDC4A
+	1.62527075710929267416e+01, // 0x403040B171814BB4
+}
+var q0S2 = [6]float64{
+	3.03655848355219184498e+01,  // 0x403E5D96F7C07AED
+	2.69348118608049844624e+02,  // 0x4070D591E4D14B40
+	8.44783757595320139444e+02,  // 0x408A664522B3BF22
+	8.82935845112488550512e+02,  // 0x408B977C9C5CC214
+	2.12666388511798828631e+02,  // 0x406A95530E001365
+	-5.31095493882666946917e+00, // 0xC0153E6AF8B32931
+}
+
+func qzero(x float64) float64 {
+	var p, q *[6]float64
+	if x >= 8 {
+		p = &q0R8
+		q = &q0S8
+	} else if x >= 4.5454 {
+		p = &q0R5
+		q = &q0S5
+	} else if x >= 2.8571 {
+		p = &q0R3
+		q = &q0S3
+	} else if x >= 2 {
+		p = &q0R2
+		q = &q0S2
+	}
+	z := 1 / (x * x)
+	r := p[0] + z*(p[1]+z*(p[2]+z*(p[3]+z*(p[4]+z*p[5]))))
+	s := 1 + z*(q[0]+z*(q[1]+z*(q[2]+z*(q[3]+z*(q[4]+z*q[5])))))
+	return (-0.125 + r/s) / x
+}
diff --git a/contrib/go/_std_1.19/src/math/j1.go b/contrib/go/_std_1.19/src/math/j1.go
new file mode 100644
index 0000000000..cc19e75b95
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/j1.go
@@ -0,0 +1,424 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+	Bessel function of the first and second kinds of order one.
+*/
+
+// The original C code and the long comment below are
+// from FreeBSD's /usr/src/lib/msun/src/e_j1.c and
+// came with this notice. The go code is a simplified
+// version of the original C.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+// __ieee754_j1(x), __ieee754_y1(x)
+// Bessel function of the first and second kinds of order one.
+// Method -- j1(x):
+//      1. For tiny x, we use j1(x) = x/2 - x**3/16 + x**5/384 - ...
+//      2. Reduce x to |x| since j1(x)=-j1(-x),  and
+//         for x in (0,2)
+//              j1(x) = x/2 + x*z*R0/S0,  where z = x*x;
+//         (precision:  |j1/x - 1/2 - R0/S0 |<2**-61.51 )
+//         for x in (2,inf)
+//              j1(x) = sqrt(2/(pi*x))*(p1(x)*cos(x1)-q1(x)*sin(x1))
+//              y1(x) = sqrt(2/(pi*x))*(p1(x)*sin(x1)+q1(x)*cos(x1))
+//         where x1 = x-3*pi/4. It is better to compute sin(x1),cos(x1)
+//         as follow:
+//              cos(x1) =  cos(x)cos(3pi/4)+sin(x)sin(3pi/4)
+//                      =  1/sqrt(2) * (sin(x) - cos(x))
+//              sin(x1) =  sin(x)cos(3pi/4)-cos(x)sin(3pi/4)
+//                      = -1/sqrt(2) * (sin(x) + cos(x))
+//         (To avoid cancellation, use
+//              sin(x) +- cos(x) = -cos(2x)/(sin(x) -+ cos(x))
+//         to compute the worse one.)
+//
+//      3 Special cases
+//              j1(nan)= nan
+//              j1(0) = 0
+//              j1(inf) = 0
+//
+// Method -- y1(x):
+//      1. screen out x<=0 cases: y1(0)=-inf, y1(x<0)=NaN
+//      2. For x<2.
+//         Since
+//              y1(x) = 2/pi*(j1(x)*(ln(x/2)+Euler)-1/x-x/2+5/64*x**3-...)
+//         therefore y1(x)-2/pi*j1(x)*ln(x)-1/x is an odd function.
+//         We use the following function to approximate y1,
+//              y1(x) = x*U(z)/V(z) + (2/pi)*(j1(x)*ln(x)-1/x), z= x**2
+//         where for x in [0,2] (abs err less than 2**-65.89)
+//              U(z) = U0[0] + U0[1]*z + ... + U0[4]*z**4
+//              V(z) = 1  + v0[0]*z + ... + v0[4]*z**5
+//         Note: For tiny x, 1/x dominate y1 and hence
+//              y1(tiny) = -2/pi/tiny, (choose tiny<2**-54)
+//      3. For x>=2.
+//               y1(x) = sqrt(2/(pi*x))*(p1(x)*sin(x1)+q1(x)*cos(x1))
+//         where x1 = x-3*pi/4. It is better to compute sin(x1),cos(x1)
+//         by method mentioned above.
+
+// J1 returns the order-one Bessel function of the first kind.
+//
+// Special cases are:
+//
+//	J1(±Inf) = 0
+//	J1(NaN) = NaN
+func J1(x float64) float64 {
+	const (
+		TwoM27 = 1.0 / (1 << 27) // 2**-27 0x3e40000000000000
+		Two129 = 1 << 129        // 2**129 0x4800000000000000
+		// R0/S0 on [0, 2]
+		R00 = -6.25000000000000000000e-02 // 0xBFB0000000000000
+		R01 = 1.40705666955189706048e-03  // 0x3F570D9F98472C61
+		R02 = -1.59955631084035597520e-05 // 0xBEF0C5C6BA169668
+		R03 = 4.96727999609584448412e-08  // 0x3E6AAAFA46CA0BD9
+		S01 = 1.91537599538363460805e-02  // 0x3F939D0B12637E53
+		S02 = 1.85946785588630915560e-04  // 0x3F285F56B9CDF664
+		S03 = 1.17718464042623683263e-06  // 0x3EB3BFF8333F8498
+		S04 = 5.04636257076217042715e-09  // 0x3E35AC88C97DFF2C
+		S05 = 1.23542274426137913908e-11  // 0x3DAB2ACFCFB97ED8
+	)
+	// special cases
+	switch {
+	case IsNaN(x):
+		return x
+	case IsInf(x, 0) || x == 0:
+		return 0
+	}
+
+	sign := false
+	if x < 0 {
+		x = -x
+		sign = true
+	}
+	if x >= 2 {
+		s, c := Sincos(x)
+		ss := -s - c
+		cc := s - c
+
+		// make sure x+x does not overflow
+		if x < MaxFloat64/2 {
+			z := Cos(x + x)
+			if s*c > 0 {
+				cc = z / ss
+			} else {
+				ss = z / cc
+			}
+		}
+
+		// j1(x) = 1/sqrt(pi) * (P(1,x)*cc - Q(1,x)*ss) / sqrt(x)
+		// y1(x) = 1/sqrt(pi) * (P(1,x)*ss + Q(1,x)*cc) / sqrt(x)
+
+		var z float64
+		if x > Two129 {
+			z = (1 / SqrtPi) * cc / Sqrt(x)
+		} else {
+			u := pone(x)
+			v := qone(x)
+			z = (1 / SqrtPi) * (u*cc - v*ss) / Sqrt(x)
+		}
+		if sign {
+			return -z
+		}
+		return z
+	}
+	if x < TwoM27 { // |x|<2**-27
+		return 0.5 * x // inexact if x!=0 necessary
+	}
+	z := x * x
+	r := z * (R00 + z*(R01+z*(R02+z*R03)))
+	s := 1.0 + z*(S01+z*(S02+z*(S03+z*(S04+z*S05))))
+	r *= x
+	z = 0.5*x + r/s
+	if sign {
+		return -z
+	}
+	return z
+}
+
+// Y1 returns the order-one Bessel function of the second kind.
+//
+// Special cases are:
+//
+//	Y1(+Inf) = 0
+//	Y1(0) = -Inf
+//	Y1(x < 0) = NaN
+//	Y1(NaN) = NaN
+func Y1(x float64) float64 {
+	const (
+		TwoM54 = 1.0 / (1 << 54)             // 2**-54 0x3c90000000000000
+		Two129 = 1 << 129                    // 2**129 0x4800000000000000
+		U00    = -1.96057090646238940668e-01 // 0xBFC91866143CBC8A
+		U01    = 5.04438716639811282616e-02  // 0x3FA9D3C776292CD1
+		U02    = -1.91256895875763547298e-03 // 0xBF5F55E54844F50F
+		U03    = 2.35252600561610495928e-05  // 0x3EF8AB038FA6B88E
+		U04    = -9.19099158039878874504e-08 // 0xBE78AC00569105B8
+		V00    = 1.99167318236649903973e-02  // 0x3F94650D3F4DA9F0
+		V01    = 2.02552581025135171496e-04  // 0x3F2A8C896C257764
+		V02    = 1.35608801097516229404e-06  // 0x3EB6C05A894E8CA6
+		V03    = 6.22741452364621501295e-09  // 0x3E3ABF1D5BA69A86
+		V04    = 1.66559246207992079114e-11  // 0x3DB25039DACA772A
+	)
+	// special cases
+	switch {
+	case x < 0 || IsNaN(x):
+		return NaN()
+	case IsInf(x, 1):
+		return 0
+	case x == 0:
+		return Inf(-1)
+	}
+
+	if x >= 2 {
+		s, c := Sincos(x)
+		ss := -s - c
+		cc := s - c
+
+		// make sure x+x does not overflow
+		if x < MaxFloat64/2 {
+			z := Cos(x + x)
+			if s*c > 0 {
+				cc = z / ss
+			} else {
+				ss = z / cc
+			}
+		}
+		// y1(x) = sqrt(2/(pi*x))*(p1(x)*sin(x0)+q1(x)*cos(x0))
+		// where x0 = x-3pi/4
+		//     Better formula:
+		//         cos(x0) = cos(x)cos(3pi/4)+sin(x)sin(3pi/4)
+		//                 =  1/sqrt(2) * (sin(x) - cos(x))
+		//         sin(x0) = sin(x)cos(3pi/4)-cos(x)sin(3pi/4)
+		//                 = -1/sqrt(2) * (cos(x) + sin(x))
+		// To avoid cancellation, use
+		//     sin(x) +- cos(x) = -cos(2x)/(sin(x) -+ cos(x))
+		// to compute the worse one.
+
+		var z float64
+		if x > Two129 {
+			z = (1 / SqrtPi) * ss / Sqrt(x)
+		} else {
+			u := pone(x)
+			v := qone(x)
+			z = (1 / SqrtPi) * (u*ss + v*cc) / Sqrt(x)
+		}
+		return z
+	}
+	if x <= TwoM54 { // x < 2**-54
+		return -(2 / Pi) / x
+	}
+	z := x * x
+	u := U00 + z*(U01+z*(U02+z*(U03+z*U04)))
+	v := 1 + z*(V00+z*(V01+z*(V02+z*(V03+z*V04))))
+	return x*(u/v) + (2/Pi)*(J1(x)*Log(x)-1/x)
+}
+
+// For x >= 8, the asymptotic expansions of pone is
+//      1 + 15/128 s**2 - 4725/2**15 s**4 - ..., where s = 1/x.
+// We approximate pone by
+//      pone(x) = 1 + (R/S)
+// where R = pr0 + pr1*s**2 + pr2*s**4 + ... + pr5*s**10
+//       S = 1 + ps0*s**2 + ... + ps4*s**10
+// and
+//      | pone(x)-1-R/S | <= 2**(-60.06)
+
+// for x in [inf, 8]=1/[0,0.125]
+var p1R8 = [6]float64{
+	0.00000000000000000000e+00, // 0x0000000000000000
+	1.17187499999988647970e-01, // 0x3FBDFFFFFFFFFCCE
+	1.32394806593073575129e+01, // 0x402A7A9D357F7FCE
+	4.12051854307378562225e+02, // 0x4079C0D4652EA590
+	3.87474538913960532227e+03, // 0x40AE457DA3A532CC
+	7.91447954031891731574e+03, // 0x40BEEA7AC32782DD
+}
+var p1S8 = [5]float64{
+	1.14207370375678408436e+02, // 0x405C8D458E656CAC
+	3.65093083420853463394e+03, // 0x40AC85DC964D274F
+	3.69562060269033463555e+04, // 0x40E20B8697C5BB7F
+	9.76027935934950801311e+04, // 0x40F7D42CB28F17BB
+	3.08042720627888811578e+04, // 0x40DE1511697A0B2D
+}
+
+// for x in [8,4.5454] = 1/[0.125,0.22001]
+var p1R5 = [6]float64{
+	1.31990519556243522749e-11, // 0x3DAD0667DAE1CA7D
+	1.17187493190614097638e-01, // 0x3FBDFFFFE2C10043
+	6.80275127868432871736e+00, // 0x401B36046E6315E3
+	1.08308182990189109773e+02, // 0x405B13B9452602ED
+	5.17636139533199752805e+02, // 0x40802D16D052D649
+	5.28715201363337541807e+02, // 0x408085B8BB7E0CB7
+}
+var p1S5 = [5]float64{
+	5.92805987221131331921e+01, // 0x404DA3EAA8AF633D
+	9.91401418733614377743e+02, // 0x408EFB361B066701
+	5.35326695291487976647e+03, // 0x40B4E9445706B6FB
+	7.84469031749551231769e+03, // 0x40BEA4B0B8A5BB15
+	1.50404688810361062679e+03, // 0x40978030036F5E51
+}
+
+// for x in[4.5453,2.8571] = 1/[0.2199,0.35001]
+var p1R3 = [6]float64{
+	3.02503916137373618024e-09, // 0x3E29FC21A7AD9EDD
+	1.17186865567253592491e-01, // 0x3FBDFFF55B21D17B
+	3.93297750033315640650e+00, // 0x400F76BCE85EAD8A
+	3.51194035591636932736e+01, // 0x40418F489DA6D129
+	9.10550110750781271918e+01, // 0x4056C3854D2C1837
+	4.85590685197364919645e+01, // 0x4048478F8EA83EE5
+}
+var p1S3 = [5]float64{
+	3.47913095001251519989e+01, // 0x40416549A134069C
+	3.36762458747825746741e+02, // 0x40750C3307F1A75F
+	1.04687139975775130551e+03, // 0x40905B7C5037D523
+	8.90811346398256432622e+02, // 0x408BD67DA32E31E9
+	1.03787932439639277504e+02, // 0x4059F26D7C2EED53
+}
+
+// for x in [2.8570,2] = 1/[0.3499,0.5]
+var p1R2 = [6]float64{
+	1.07710830106873743082e-07, // 0x3E7CE9D4F65544F4
+	1.17176219462683348094e-01, // 0x3FBDFF42BE760D83
+	2.36851496667608785174e+00, // 0x4002F2B7F98FAEC0
+	1.22426109148261232917e+01, // 0x40287C377F71A964
+	1.76939711271687727390e+01, // 0x4031B1A8177F8EE2
+	5.07352312588818499250e+00, // 0x40144B49A574C1FE
+}
+var p1S2 = [5]float64{
+	2.14364859363821409488e+01, // 0x40356FBD8AD5ECDC
+	1.25290227168402751090e+02, // 0x405F529314F92CD5
+	2.32276469057162813669e+02, // 0x406D08D8D5A2DBD9
+	1.17679373287147100768e+02, // 0x405D6B7ADA1884A9
+	8.36463893371618283368e+00, // 0x4020BAB1F44E5192
+}
+
+func pone(x float64) float64 {
+	var p *[6]float64
+	var q *[5]float64
+	if x >= 8 {
+		p = &p1R8
+		q = &p1S8
+	} else if x >= 4.5454 {
+		p = &p1R5
+		q = &p1S5
+	} else if x >= 2.8571 {
+		p = &p1R3
+		q = &p1S3
+	} else if x >= 2 {
+		p = &p1R2
+		q = &p1S2
+	}
+	z := 1 / (x * x)
+	r := p[0] + z*(p[1]+z*(p[2]+z*(p[3]+z*(p[4]+z*p[5]))))
+	s := 1.0 + z*(q[0]+z*(q[1]+z*(q[2]+z*(q[3]+z*q[4]))))
+	return 1 + r/s
+}
+
+// For x >= 8, the asymptotic expansions of qone is
+//      3/8 s - 105/1024 s**3 - ..., where s = 1/x.
+// We approximate qone by
+//      qone(x) = s*(0.375 + (R/S))
+// where R = qr1*s**2 + qr2*s**4 + ... + qr5*s**10
+//       S = 1 + qs1*s**2 + ... + qs6*s**12
+// and
+//      | qone(x)/s -0.375-R/S | <= 2**(-61.13)
+
+// for x in [inf, 8] = 1/[0,0.125]
+var q1R8 = [6]float64{
+	0.00000000000000000000e+00,  // 0x0000000000000000
+	-1.02539062499992714161e-01, // 0xBFBA3FFFFFFFFDF3
+	-1.62717534544589987888e+01, // 0xC0304591A26779F7
+	-7.59601722513950107896e+02, // 0xC087BCD053E4B576
+	-1.18498066702429587167e+04, // 0xC0C724E740F87415
+	-4.84385124285750353010e+04, // 0xC0E7A6D065D09C6A
+}
+var q1S8 = [6]float64{
+	1.61395369700722909556e+02,  // 0x40642CA6DE5BCDE5
+	7.82538599923348465381e+03,  // 0x40BE9162D0D88419
+	1.33875336287249578163e+05,  // 0x4100579AB0B75E98
+	7.19657723683240939863e+05,  // 0x4125F65372869C19
+	6.66601232617776375264e+05,  // 0x412457D27719AD5C
+	-2.94490264303834643215e+05, // 0xC111F9690EA5AA18
+}
+
+// for x in [8,4.5454] = 1/[0.125,0.22001]
+var q1R5 = [6]float64{
+	-2.08979931141764104297e-11, // 0xBDB6FA431AA1A098
+	-1.02539050241375426231e-01, // 0xBFBA3FFFCB597FEF
+	-8.05644828123936029840e+00, // 0xC0201CE6CA03AD4B
+	-1.83669607474888380239e+02, // 0xC066F56D6CA7B9B0
+	-1.37319376065508163265e+03, // 0xC09574C66931734F
+	-2.61244440453215656817e+03, // 0xC0A468E388FDA79D
+}
+var q1S5 = [6]float64{
+	8.12765501384335777857e+01,  // 0x405451B2FF5A11B2
+	1.99179873460485964642e+03,  // 0x409F1F31E77BF839
+	1.74684851924908907677e+04,  // 0x40D10F1F0D64CE29
+	4.98514270910352279316e+04,  // 0x40E8576DAABAD197
+	2.79480751638918118260e+04,  // 0x40DB4B04CF7C364B
+	-4.71918354795128470869e+03, // 0xC0B26F2EFCFFA004
+}
+
+// for x in [4.5454,2.8571] = 1/[0.2199,0.35001] ???
+var q1R3 = [6]float64{
+	-5.07831226461766561369e-09, // 0xBE35CFA9D38FC84F
+	-1.02537829820837089745e-01, // 0xBFBA3FEB51AEED54
+	-4.61011581139473403113e+00, // 0xC01270C23302D9FF
+	-5.78472216562783643212e+01, // 0xC04CEC71C25D16DA
+	-2.28244540737631695038e+02, // 0xC06C87D34718D55F
+	-2.19210128478909325622e+02, // 0xC06B66B95F5C1BF6
+}
+var q1S3 = [6]float64{
+	4.76651550323729509273e+01,  // 0x4047D523CCD367E4
+	6.73865112676699709482e+02,  // 0x40850EEBC031EE3E
+	3.38015286679526343505e+03,  // 0x40AA684E448E7C9A
+	5.54772909720722782367e+03,  // 0x40B5ABBAA61D54A6
+	1.90311919338810798763e+03,  // 0x409DBC7A0DD4DF4B
+	-1.35201191444307340817e+02, // 0xC060E670290A311F
+}
+
+// for x in [2.8570,2] = 1/[0.3499,0.5]
+var q1R2 = [6]float64{
+	-1.78381727510958865572e-07, // 0xBE87F12644C626D2
+	-1.02517042607985553460e-01, // 0xBFBA3E8E9148B010
+	-2.75220568278187460720e+00, // 0xC006048469BB4EDA
+	-1.96636162643703720221e+01, // 0xC033A9E2C168907F
+	-4.23253133372830490089e+01, // 0xC04529A3DE104AAA
+	-2.13719211703704061733e+01, // 0xC0355F3639CF6E52
+}
+var q1S2 = [6]float64{
+	2.95333629060523854548e+01,  // 0x403D888A78AE64FF
+	2.52981549982190529136e+02,  // 0x406F9F68DB821CBA
+	7.57502834868645436472e+02,  // 0x4087AC05CE49A0F7
+	7.39393205320467245656e+02,  // 0x40871B2548D4C029
+	1.55949003336666123687e+02,  // 0x40637E5E3C3ED8D4
+	-4.95949898822628210127e+00, // 0xC013D686E71BE86B
+}
+
+func qone(x float64) float64 {
+	var p, q *[6]float64
+	if x >= 8 {
+		p = &q1R8
+		q = &q1S8
+	} else if x >= 4.5454 {
+		p = &q1R5
+		q = &q1S5
+	} else if x >= 2.8571 {
+		p = &q1R3
+		q = &q1S3
+	} else if x >= 2 {
+		p = &q1R2
+		q = &q1S2
+	}
+	z := 1 / (x * x)
+	r := p[0] + z*(p[1]+z*(p[2]+z*(p[3]+z*(p[4]+z*p[5]))))
+	s := 1 + z*(q[0]+z*(q[1]+z*(q[2]+z*(q[3]+z*(q[4]+z*q[5])))))
+	return (0.375 + r/s) / x
+}
diff --git a/contrib/go/_std_1.19/src/math/jn.go b/contrib/go/_std_1.19/src/math/jn.go
new file mode 100644
index 0000000000..3491692a96
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/jn.go
@@ -0,0 +1,306 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+	Bessel function of the first and second kinds of order n.
+*/
+
+// The original C code and the long comment below are
+// from FreeBSD's /usr/src/lib/msun/src/e_jn.c and
+// came with this notice. The go code is a simplified
+// version of the original C.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+// __ieee754_jn(n, x), __ieee754_yn(n, x)
+// floating point Bessel's function of the 1st and 2nd kind
+// of order n
+//
+// Special cases:
+//      y0(0)=y1(0)=yn(n,0) = -inf with division by zero signal;
+//      y0(-ve)=y1(-ve)=yn(n,-ve) are NaN with invalid signal.
+// Note 2. About jn(n,x), yn(n,x)
+//      For n=0, j0(x) is called,
+//      for n=1, j1(x) is called,
+//      for n<x, forward recursion is used starting
+//      from values of j0(x) and j1(x).
+//      for n>x, a continued fraction approximation to
+//      j(n,x)/j(n-1,x) is evaluated and then backward
+//      recursion is used starting from a supposed value
+//      for j(n,x). The resulting value of j(0,x) is
+//      compared with the actual value to correct the
+//      supposed value of j(n,x).
+//
+//      yn(n,x) is similar in all respects, except
+//      that forward recursion is used for all
+//      values of n>1.
+
+// Jn returns the order-n Bessel function of the first kind.
+//
+// Special cases are:
+//
+//	Jn(n, ±Inf) = 0
+//	Jn(n, NaN) = NaN
+func Jn(n int, x float64) float64 {
+	const (
+		TwoM29 = 1.0 / (1 << 29) // 2**-29 0x3e10000000000000
+		Two302 = 1 << 302        // 2**302 0x52D0000000000000
+	)
+	// special cases
+	switch {
+	case IsNaN(x):
+		return x
+	case IsInf(x, 0):
+		return 0
+	}
+	// J(-n, x) = (-1)**n * J(n, x), J(n, -x) = (-1)**n * J(n, x)
+	// Thus, J(-n, x) = J(n, -x)
+
+	if n == 0 {
+		return J0(x)
+	}
+	if x == 0 {
+		return 0
+	}
+	if n < 0 {
+		n, x = -n, -x
+	}
+	if n == 1 {
+		return J1(x)
+	}
+	sign := false
+	if x < 0 {
+		x = -x
+		if n&1 == 1 {
+			sign = true // odd n and negative x
+		}
+	}
+	var b float64
+	if float64(n) <= x {
+		// Safe to use J(n+1,x)=2n/x *J(n,x)-J(n-1,x)
+		if x >= Two302 { // x > 2**302
+
+			// (x >> n**2)
+			//          Jn(x) = cos(x-(2n+1)*pi/4)*sqrt(2/x*pi)
+			//          Yn(x) = sin(x-(2n+1)*pi/4)*sqrt(2/x*pi)
+			//          Let s=sin(x), c=cos(x),
+			//              xn=x-(2n+1)*pi/4, sqt2 = sqrt(2),then
+			//
+			//                 n    sin(xn)*sqt2    cos(xn)*sqt2
+			//              ----------------------------------
+			//                 0     s-c             c+s
+			//                 1    -s-c            -c+s
+			//                 2    -s+c            -c-s
+			//                 3     s+c             c-s
+
+			var temp float64
+			switch s, c := Sincos(x); n & 3 {
+			case 0:
+				temp = c + s
+			case 1:
+				temp = -c + s
+			case 2:
+				temp = -c - s
+			case 3:
+				temp = c - s
+			}
+			b = (1 / SqrtPi) * temp / Sqrt(x)
+		} else {
+			b = J1(x)
+			for i, a := 1, J0(x); i < n; i++ {
+				a, b = b, b*(float64(i+i)/x)-a // avoid underflow
+			}
+		}
+	} else {
+		if x < TwoM29 { // x < 2**-29
+			// x is tiny, return the first Taylor expansion of J(n,x)
+			// J(n,x) = 1/n!*(x/2)**n  - ...
+
+			if n > 33 { // underflow
+				b = 0
+			} else {
+				temp := x * 0.5
+				b = temp
+				a := 1.0
+				for i := 2; i <= n; i++ {
+					a *= float64(i) // a = n!
+					b *= temp       // b = (x/2)**n
+				}
+				b /= a
+			}
+		} else {
+			// use backward recurrence
+			//                      x      x**2      x**2
+			//  J(n,x)/J(n-1,x) =  ----   ------   ------   .....
+			//                      2n  - 2(n+1) - 2(n+2)
+			//
+			//                      1      1        1
+			//  (for large x)   =  ----  ------   ------   .....
+			//                      2n   2(n+1)   2(n+2)
+			//                      -- - ------ - ------ -
+			//                       x     x         x
+			//
+			// Let w = 2n/x and h=2/x, then the above quotient
+			// is equal to the continued fraction:
+			//                  1
+			//      = -----------------------
+			//                     1
+			//         w - -----------------
+			//                        1
+			//              w+h - ---------
+			//                     w+2h - ...
+			//
+			// To determine how many terms needed, let
+			// Q(0) = w, Q(1) = w(w+h) - 1,
+			// Q(k) = (w+k*h)*Q(k-1) - Q(k-2),
+			// When Q(k) > 1e4	good for single
+			// When Q(k) > 1e9	good for double
+			// When Q(k) > 1e17	good for quadruple
+
+			// determine k
+			w := float64(n+n) / x
+			h := 2 / x
+			q0 := w
+			z := w + h
+			q1 := w*z - 1
+			k := 1
+			for q1 < 1e9 {
+				k++
+				z += h
+				q0, q1 = q1, z*q1-q0
+			}
+			m := n + n
+			t := 0.0
+			for i := 2 * (n + k); i >= m; i -= 2 {
+				t = 1 / (float64(i)/x - t)
+			}
+			a := t
+			b = 1
+			//  estimate log((2/x)**n*n!) = n*log(2/x)+n*ln(n)
+			//  Hence, if n*(log(2n/x)) > ...
+			//  single 8.8722839355e+01
+			//  double 7.09782712893383973096e+02
+			//  long double 1.1356523406294143949491931077970765006170e+04
+			//  then recurrent value may overflow and the result is
+			//  likely underflow to zero
+
+			tmp := float64(n)
+			v := 2 / x
+			tmp = tmp * Log(Abs(v*tmp))
+			if tmp < 7.09782712893383973096e+02 {
+				for i := n - 1; i > 0; i-- {
+					di := float64(i + i)
+					a, b = b, b*di/x-a
+				}
+			} else {
+				for i := n - 1; i > 0; i-- {
+					di := float64(i + i)
+					a, b = b, b*di/x-a
+					// scale b to avoid spurious overflow
+					if b > 1e100 {
+						a /= b
+						t /= b
+						b = 1
+					}
+				}
+			}
+			b = t * J0(x) / b
+		}
+	}
+	if sign {
+		return -b
+	}
+	return b
+}
+
+// Yn returns the order-n Bessel function of the second kind.
+//
+// Special cases are:
+//
+//	Yn(n, +Inf) = 0
+//	Yn(n ≥ 0, 0) = -Inf
+//	Yn(n < 0, 0) = +Inf if n is odd, -Inf if n is even
+//	Yn(n, x < 0) = NaN
+//	Yn(n, NaN) = NaN
+func Yn(n int, x float64) float64 {
+	const Two302 = 1 << 302 // 2**302 0x52D0000000000000
+	// special cases
+	switch {
+	case x < 0 || IsNaN(x):
+		return NaN()
+	case IsInf(x, 1):
+		return 0
+	}
+
+	if n == 0 {
+		return Y0(x)
+	}
+	if x == 0 {
+		if n < 0 && n&1 == 1 {
+			return Inf(1)
+		}
+		return Inf(-1)
+	}
+	sign := false
+	if n < 0 {
+		n = -n
+		if n&1 == 1 {
+			sign = true // sign true if n < 0 && |n| odd
+		}
+	}
+	if n == 1 {
+		if sign {
+			return -Y1(x)
+		}
+		return Y1(x)
+	}
+	var b float64
+	if x >= Two302 { // x > 2**302
+		// (x >> n**2)
+		//	    Jn(x) = cos(x-(2n+1)*pi/4)*sqrt(2/x*pi)
+		//	    Yn(x) = sin(x-(2n+1)*pi/4)*sqrt(2/x*pi)
+		//	    Let s=sin(x), c=cos(x),
+		//		xn=x-(2n+1)*pi/4, sqt2 = sqrt(2),then
+		//
+		//		   n	sin(xn)*sqt2	cos(xn)*sqt2
+		//		----------------------------------
+		//		   0	 s-c		 c+s
+		//		   1	-s-c 		-c+s
+		//		   2	-s+c		-c-s
+		//		   3	 s+c		 c-s
+
+		var temp float64
+		switch s, c := Sincos(x); n & 3 {
+		case 0:
+			temp = s - c
+		case 1:
+			temp = -s - c
+		case 2:
+			temp = -s + c
+		case 3:
+			temp = s + c
+		}
+		b = (1 / SqrtPi) * temp / Sqrt(x)
+	} else {
+		a := Y0(x)
+		b = Y1(x)
+		// quit if b is -inf
+		for i := 1; i < n && !IsInf(b, -1); i++ {
+			a, b = b, (float64(i+i)/x)*b-a
+		}
+	}
+	if sign {
+		return -b
+	}
+	return b
+}
diff --git a/contrib/go/_std_1.19/src/math/ldexp.go b/contrib/go/_std_1.19/src/math/ldexp.go
new file mode 100644
index 0000000000..df365c0b1a
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/ldexp.go
@@ -0,0 +1,51 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Ldexp is the inverse of Frexp.
+// It returns frac × 2**exp.
+//
+// Special cases are:
+//
+//	Ldexp(±0, exp) = ±0
+//	Ldexp(±Inf, exp) = ±Inf
+//	Ldexp(NaN, exp) = NaN
+func Ldexp(frac float64, exp int) float64 {
+	if haveArchLdexp {
+		return archLdexp(frac, exp)
+	}
+	return ldexp(frac, exp)
+}
+
+func ldexp(frac float64, exp int) float64 {
+	// special cases
+	switch {
+	case frac == 0:
+		return frac // correctly return -0
+	case IsInf(frac, 0) || IsNaN(frac):
+		return frac
+	}
+	frac, e := normalize(frac)
+	exp += e
+	x := Float64bits(frac)
+	exp += int(x>>shift)&mask - bias
+	if exp < -1075 {
+		return Copysign(0, frac) // underflow
+	}
+	if exp > 1023 { // overflow
+		if frac < 0 {
+			return Inf(-1)
+		}
+		return Inf(1)
+	}
+	var m float64 = 1
+	if exp < -1022 { // denormal
+		exp += 53
+		m = 1.0 / (1 << 53) // 2**-53
+	}
+	x &^= mask << shift
+	x |= uint64(exp+bias) << shift
+	return m * Float64frombits(x)
+}
diff --git a/contrib/go/_std_1.19/src/math/lgamma.go b/contrib/go/_std_1.19/src/math/lgamma.go
new file mode 100644
index 0000000000..4058ad6631
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/lgamma.go
@@ -0,0 +1,366 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+	Floating-point logarithm of the Gamma function.
+*/
+
+// The original C code and the long comment below are
+// from FreeBSD's /usr/src/lib/msun/src/e_lgamma_r.c and
+// came with this notice. The go code is a simplified
+// version of the original C.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+// __ieee754_lgamma_r(x, signgamp)
+// Reentrant version of the logarithm of the Gamma function
+// with user provided pointer for the sign of Gamma(x).
+//
+// Method:
+//   1. Argument Reduction for 0 < x <= 8
+//      Since gamma(1+s)=s*gamma(s), for x in [0,8], we may
+//      reduce x to a number in [1.5,2.5] by
+//              lgamma(1+s) = log(s) + lgamma(s)
+//      for example,
+//              lgamma(7.3) = log(6.3) + lgamma(6.3)
+//                          = log(6.3*5.3) + lgamma(5.3)
+//                          = log(6.3*5.3*4.3*3.3*2.3) + lgamma(2.3)
+//   2. Polynomial approximation of lgamma around its
+//      minimum (ymin=1.461632144968362245) to maintain monotonicity.
+//      On [ymin-0.23, ymin+0.27] (i.e., [1.23164,1.73163]), use
+//              Let z = x-ymin;
+//              lgamma(x) = -1.214862905358496078218 + z**2*poly(z)
+//              poly(z) is a 14 degree polynomial.
+//   2. Rational approximation in the primary interval [2,3]
+//      We use the following approximation:
+//              s = x-2.0;
+//              lgamma(x) = 0.5*s + s*P(s)/Q(s)
+//      with accuracy
+//              |P/Q - (lgamma(x)-0.5s)| < 2**-61.71
+//      Our algorithms are based on the following observation
+//
+//                             zeta(2)-1    2    zeta(3)-1    3
+// lgamma(2+s) = s*(1-Euler) + --------- * s  -  --------- * s  + ...
+//                                 2                 3
+//
+//      where Euler = 0.5772156649... is the Euler constant, which
+//      is very close to 0.5.
+//
+//   3. For x>=8, we have
+//      lgamma(x)~(x-0.5)log(x)-x+0.5*log(2pi)+1/(12x)-1/(360x**3)+....
+//      (better formula:
+//         lgamma(x)~(x-0.5)*(log(x)-1)-.5*(log(2pi)-1) + ...)
+//      Let z = 1/x, then we approximation
+//              f(z) = lgamma(x) - (x-0.5)(log(x)-1)
+//      by
+//                                  3       5             11
+//              w = w0 + w1*z + w2*z  + w3*z  + ... + w6*z
+//      where
+//              |w - f(z)| < 2**-58.74
+//
+//   4. For negative x, since (G is gamma function)
+//              -x*G(-x)*G(x) = pi/sin(pi*x),
+//      we have
+//              G(x) = pi/(sin(pi*x)*(-x)*G(-x))
+//      since G(-x) is positive, sign(G(x)) = sign(sin(pi*x)) for x<0
+//      Hence, for x<0, signgam = sign(sin(pi*x)) and
+//              lgamma(x) = log(|Gamma(x)|)
+//                        = log(pi/(|x*sin(pi*x)|)) - lgamma(-x);
+//      Note: one should avoid computing pi*(-x) directly in the
+//            computation of sin(pi*(-x)).
+//
+//   5. Special Cases
+//              lgamma(2+s) ~ s*(1-Euler) for tiny s
+//              lgamma(1)=lgamma(2)=0
+//              lgamma(x) ~ -log(x) for tiny x
+//              lgamma(0) = lgamma(inf) = inf
+//              lgamma(-integer) = +-inf
+//
+//
+
+var _lgamA = [...]float64{
+	7.72156649015328655494e-02, // 0x3FB3C467E37DB0C8
+	3.22467033424113591611e-01, // 0x3FD4A34CC4A60FAD
+	6.73523010531292681824e-02, // 0x3FB13E001A5562A7
+	2.05808084325167332806e-02, // 0x3F951322AC92547B
+	7.38555086081402883957e-03, // 0x3F7E404FB68FEFE8
+	2.89051383673415629091e-03, // 0x3F67ADD8CCB7926B
+	1.19270763183362067845e-03, // 0x3F538A94116F3F5D
+	5.10069792153511336608e-04, // 0x3F40B6C689B99C00
+	2.20862790713908385557e-04, // 0x3F2CF2ECED10E54D
+	1.08011567247583939954e-04, // 0x3F1C5088987DFB07
+	2.52144565451257326939e-05, // 0x3EFA7074428CFA52
+	4.48640949618915160150e-05, // 0x3F07858E90A45837
+}
+var _lgamR = [...]float64{
+	1.0,                        // placeholder
+	1.39200533467621045958e+00, // 0x3FF645A762C4AB74
+	7.21935547567138069525e-01, // 0x3FE71A1893D3DCDC
+	1.71933865632803078993e-01, // 0x3FC601EDCCFBDF27
+	1.86459191715652901344e-02, // 0x3F9317EA742ED475
+	7.77942496381893596434e-04, // 0x3F497DDACA41A95B
+	7.32668430744625636189e-06, // 0x3EDEBAF7A5B38140
+}
+var _lgamS = [...]float64{
+	-7.72156649015328655494e-02, // 0xBFB3C467E37DB0C8
+	2.14982415960608852501e-01,  // 0x3FCB848B36E20878
+	3.25778796408930981787e-01,  // 0x3FD4D98F4F139F59
+	1.46350472652464452805e-01,  // 0x3FC2BB9CBEE5F2F7
+	2.66422703033638609560e-02,  // 0x3F9B481C7E939961
+	1.84028451407337715652e-03,  // 0x3F5E26B67368F239
+	3.19475326584100867617e-05,  // 0x3F00BFECDD17E945
+}
+var _lgamT = [...]float64{
+	4.83836122723810047042e-01,  // 0x3FDEF72BC8EE38A2
+	-1.47587722994593911752e-01, // 0xBFC2E4278DC6C509
+	6.46249402391333854778e-02,  // 0x3FB08B4294D5419B
+	-3.27885410759859649565e-02, // 0xBFA0C9A8DF35B713
+	1.79706750811820387126e-02,  // 0x3F9266E7970AF9EC
+	-1.03142241298341437450e-02, // 0xBF851F9FBA91EC6A
+	6.10053870246291332635e-03,  // 0x3F78FCE0E370E344
+	-3.68452016781138256760e-03, // 0xBF6E2EFFB3E914D7
+	2.25964780900612472250e-03,  // 0x3F6282D32E15C915
+	-1.40346469989232843813e-03, // 0xBF56FE8EBF2D1AF1
+	8.81081882437654011382e-04,  // 0x3F4CDF0CEF61A8E9
+	-5.38595305356740546715e-04, // 0xBF41A6109C73E0EC
+	3.15632070903625950361e-04,  // 0x3F34AF6D6C0EBBF7
+	-3.12754168375120860518e-04, // 0xBF347F24ECC38C38
+	3.35529192635519073543e-04,  // 0x3F35FD3EE8C2D3F4
+}
+var _lgamU = [...]float64{
+	-7.72156649015328655494e-02, // 0xBFB3C467E37DB0C8
+	6.32827064025093366517e-01,  // 0x3FE4401E8B005DFF
+	1.45492250137234768737e+00,  // 0x3FF7475CD119BD6F
+	9.77717527963372745603e-01,  // 0x3FEF497644EA8450
+	2.28963728064692451092e-01,  // 0x3FCD4EAEF6010924
+	1.33810918536787660377e-02,  // 0x3F8B678BBF2BAB09
+}
+var _lgamV = [...]float64{
+	1.0,
+	2.45597793713041134822e+00, // 0x4003A5D7C2BD619C
+	2.12848976379893395361e+00, // 0x40010725A42B18F5
+	7.69285150456672783825e-01, // 0x3FE89DFBE45050AF
+	1.04222645593369134254e-01, // 0x3FBAAE55D6537C88
+	3.21709242282423911810e-03, // 0x3F6A5ABB57D0CF61
+}
+var _lgamW = [...]float64{
+	4.18938533204672725052e-01,  // 0x3FDACFE390C97D69
+	8.33333333333329678849e-02,  // 0x3FB555555555553B
+	-2.77777777728775536470e-03, // 0xBF66C16C16B02E5C
+	7.93650558643019558500e-04,  // 0x3F4A019F98CF38B6
+	-5.95187557450339963135e-04, // 0xBF4380CB8C0FE741
+	8.36339918996282139126e-04,  // 0x3F4B67BA4CDAD5D1
+	-1.63092934096575273989e-03, // 0xBF5AB89D0B9E43E4
+}
+
+// Lgamma returns the natural logarithm and sign (-1 or +1) of Gamma(x).
+//
+// Special cases are:
+//
+//	Lgamma(+Inf) = +Inf
+//	Lgamma(0) = +Inf
+//	Lgamma(-integer) = +Inf
+//	Lgamma(-Inf) = -Inf
+//	Lgamma(NaN) = NaN
+func Lgamma(x float64) (lgamma float64, sign int) {
+	const (
+		Ymin  = 1.461632144968362245
+		Two52 = 1 << 52                     // 0x4330000000000000 ~4.5036e+15
+		Two53 = 1 << 53                     // 0x4340000000000000 ~9.0072e+15
+		Two58 = 1 << 58                     // 0x4390000000000000 ~2.8823e+17
+		Tiny  = 1.0 / (1 << 70)             // 0x3b90000000000000 ~8.47033e-22
+		Tc    = 1.46163214496836224576e+00  // 0x3FF762D86356BE3F
+		Tf    = -1.21486290535849611461e-01 // 0xBFBF19B9BCC38A42
+		// Tt = -(tail of Tf)
+		Tt = -3.63867699703950536541e-18 // 0xBC50C7CAA48A971F
+	)
+	// special cases
+	sign = 1
+	switch {
+	case IsNaN(x):
+		lgamma = x
+		return
+	case IsInf(x, 0):
+		lgamma = x
+		return
+	case x == 0:
+		lgamma = Inf(1)
+		return
+	}
+
+	neg := false
+	if x < 0 {
+		x = -x
+		neg = true
+	}
+
+	if x < Tiny { // if |x| < 2**-70, return -log(|x|)
+		if neg {
+			sign = -1
+		}
+		lgamma = -Log(x)
+		return
+	}
+	var nadj float64
+	if neg {
+		if x >= Two52 { // |x| >= 2**52, must be -integer
+			lgamma = Inf(1)
+			return
+		}
+		t := sinPi(x)
+		if t == 0 {
+			lgamma = Inf(1) // -integer
+			return
+		}
+		nadj = Log(Pi / Abs(t*x))
+		if t < 0 {
+			sign = -1
+		}
+	}
+
+	switch {
+	case x == 1 || x == 2: // purge off 1 and 2
+		lgamma = 0
+		return
+	case x < 2: // use lgamma(x) = lgamma(x+1) - log(x)
+		var y float64
+		var i int
+		if x <= 0.9 {
+			lgamma = -Log(x)
+			switch {
+			case x >= (Ymin - 1 + 0.27): // 0.7316 <= x <=  0.9
+				y = 1 - x
+				i = 0
+			case x >= (Ymin - 1 - 0.27): // 0.2316 <= x < 0.7316
+				y = x - (Tc - 1)
+				i = 1
+			default: // 0 < x < 0.2316
+				y = x
+				i = 2
+			}
+		} else {
+			lgamma = 0
+			switch {
+			case x >= (Ymin + 0.27): // 1.7316 <= x < 2
+				y = 2 - x
+				i = 0
+			case x >= (Ymin - 0.27): // 1.2316 <= x < 1.7316
+				y = x - Tc
+				i = 1
+			default: // 0.9 < x < 1.2316
+				y = x - 1
+				i = 2
+			}
+		}
+		switch i {
+		case 0:
+			z := y * y
+			p1 := _lgamA[0] + z*(_lgamA[2]+z*(_lgamA[4]+z*(_lgamA[6]+z*(_lgamA[8]+z*_lgamA[10]))))
+			p2 := z * (_lgamA[1] + z*(+_lgamA[3]+z*(_lgamA[5]+z*(_lgamA[7]+z*(_lgamA[9]+z*_lgamA[11])))))
+			p := y*p1 + p2
+			lgamma += (p - 0.5*y)
+		case 1:
+			z := y * y
+			w := z * y
+			p1 := _lgamT[0] + w*(_lgamT[3]+w*(_lgamT[6]+w*(_lgamT[9]+w*_lgamT[12]))) // parallel comp
+			p2 := _lgamT[1] + w*(_lgamT[4]+w*(_lgamT[7]+w*(_lgamT[10]+w*_lgamT[13])))
+			p3 := _lgamT[2] + w*(_lgamT[5]+w*(_lgamT[8]+w*(_lgamT[11]+w*_lgamT[14])))
+			p := z*p1 - (Tt - w*(p2+y*p3))
+			lgamma += (Tf + p)
+		case 2:
+			p1 := y * (_lgamU[0] + y*(_lgamU[1]+y*(_lgamU[2]+y*(_lgamU[3]+y*(_lgamU[4]+y*_lgamU[5])))))
+			p2 := 1 + y*(_lgamV[1]+y*(_lgamV[2]+y*(_lgamV[3]+y*(_lgamV[4]+y*_lgamV[5]))))
+			lgamma += (-0.5*y + p1/p2)
+		}
+	case x < 8: // 2 <= x < 8
+		i := int(x)
+		y := x - float64(i)
+		p := y * (_lgamS[0] + y*(_lgamS[1]+y*(_lgamS[2]+y*(_lgamS[3]+y*(_lgamS[4]+y*(_lgamS[5]+y*_lgamS[6]))))))
+		q := 1 + y*(_lgamR[1]+y*(_lgamR[2]+y*(_lgamR[3]+y*(_lgamR[4]+y*(_lgamR[5]+y*_lgamR[6])))))
+		lgamma = 0.5*y + p/q
+		z := 1.0 // Lgamma(1+s) = Log(s) + Lgamma(s)
+		switch i {
+		case 7:
+			z *= (y + 6)
+			fallthrough
+		case 6:
+			z *= (y + 5)
+			fallthrough
+		case 5:
+			z *= (y + 4)
+			fallthrough
+		case 4:
+			z *= (y + 3)
+			fallthrough
+		case 3:
+			z *= (y + 2)
+			lgamma += Log(z)
+		}
+	case x < Two58: // 8 <= x < 2**58
+		t := Log(x)
+		z := 1 / x
+		y := z * z
+		w := _lgamW[0] + z*(_lgamW[1]+y*(_lgamW[2]+y*(_lgamW[3]+y*(_lgamW[4]+y*(_lgamW[5]+y*_lgamW[6])))))
+		lgamma = (x-0.5)*(t-1) + w
+	default: // 2**58 <= x <= Inf
+		lgamma = x * (Log(x) - 1)
+	}
+	if neg {
+		lgamma = nadj - lgamma
+	}
+	return
+}
+
+// sinPi(x) is a helper function for negative x
+func sinPi(x float64) float64 {
+	const (
+		Two52 = 1 << 52 // 0x4330000000000000 ~4.5036e+15
+		Two53 = 1 << 53 // 0x4340000000000000 ~9.0072e+15
+	)
+	if x < 0.25 {
+		return -Sin(Pi * x)
+	}
+
+	// argument reduction
+	z := Floor(x)
+	var n int
+	if z != x { // inexact
+		x = Mod(x, 2)
+		n = int(x * 4)
+	} else {
+		if x >= Two53 { // x must be even
+			x = 0
+			n = 0
+		} else {
+			if x < Two52 {
+				z = x + Two52 // exact
+			}
+			n = int(1 & Float64bits(z))
+			x = float64(n)
+			n <<= 2
+		}
+	}
+	switch n {
+	case 0:
+		x = Sin(Pi * x)
+	case 1, 2:
+		x = Cos(Pi * (0.5 - x))
+	case 3, 4:
+		x = Sin(Pi * (1 - x))
+	case 5, 6:
+		x = -Cos(Pi * (x - 1.5))
+	default:
+		x = Sin(Pi * (x - 2))
+	}
+	return -x
+}
diff --git a/contrib/go/_std_1.19/src/math/log.go b/contrib/go/_std_1.19/src/math/log.go
new file mode 100644
index 0000000000..695a545e7f
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/log.go
@@ -0,0 +1,129 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+	Floating-point logarithm.
+*/
+
+// The original C code, the long comment, and the constants
+// below are from FreeBSD's /usr/src/lib/msun/src/e_log.c
+// and came with this notice. The go code is a simpler
+// version of the original C.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+// __ieee754_log(x)
+// Return the logarithm of x
+//
+// Method :
+//   1. Argument Reduction: find k and f such that
+//			x = 2**k * (1+f),
+//	   where  sqrt(2)/2 < 1+f < sqrt(2) .
+//
+//   2. Approximation of log(1+f).
+//	Let s = f/(2+f) ; based on log(1+f) = log(1+s) - log(1-s)
+//		 = 2s + 2/3 s**3 + 2/5 s**5 + .....,
+//	     	 = 2s + s*R
+//      We use a special Reme algorithm on [0,0.1716] to generate
+//	a polynomial of degree 14 to approximate R.  The maximum error
+//	of this polynomial approximation is bounded by 2**-58.45. In
+//	other words,
+//		        2      4      6      8      10      12      14
+//	    R(z) ~ L1*s +L2*s +L3*s +L4*s +L5*s  +L6*s  +L7*s
+//	(the values of L1 to L7 are listed in the program) and
+//	    |      2          14          |     -58.45
+//	    | L1*s +...+L7*s    -  R(z) | <= 2
+//	    |                             |
+//	Note that 2s = f - s*f = f - hfsq + s*hfsq, where hfsq = f*f/2.
+//	In order to guarantee error in log below 1ulp, we compute log by
+//		log(1+f) = f - s*(f - R)		(if f is not too large)
+//		log(1+f) = f - (hfsq - s*(hfsq+R)).	(better accuracy)
+//
+//	3. Finally,  log(x) = k*Ln2 + log(1+f).
+//			    = k*Ln2_hi+(f-(hfsq-(s*(hfsq+R)+k*Ln2_lo)))
+//	   Here Ln2 is split into two floating point number:
+//			Ln2_hi + Ln2_lo,
+//	   where n*Ln2_hi is always exact for |n| < 2000.
+//
+// Special cases:
+//	log(x) is NaN with signal if x < 0 (including -INF) ;
+//	log(+INF) is +INF; log(0) is -INF with signal;
+//	log(NaN) is that NaN with no signal.
+//
+// Accuracy:
+//	according to an error analysis, the error is always less than
+//	1 ulp (unit in the last place).
+//
+// Constants:
+// The hexadecimal values are the intended ones for the following
+// constants. The decimal values may be used, provided that the
+// compiler will convert from decimal to binary accurately enough
+// to produce the hexadecimal values shown.
+
+// Log returns the natural logarithm of x.
+//
+// Special cases are:
+//
+//	Log(+Inf) = +Inf
+//	Log(0) = -Inf
+//	Log(x < 0) = NaN
+//	Log(NaN) = NaN
+func Log(x float64) float64 {
+	if haveArchLog {
+		return archLog(x)
+	}
+	return log(x)
+}
+
+func log(x float64) float64 {
+	const (
+		Ln2Hi = 6.93147180369123816490e-01 /* 3fe62e42 fee00000 */
+		Ln2Lo = 1.90821492927058770002e-10 /* 3dea39ef 35793c76 */
+		L1    = 6.666666666666735130e-01   /* 3FE55555 55555593 */
+		L2    = 3.999999999940941908e-01   /* 3FD99999 9997FA04 */
+		L3    = 2.857142874366239149e-01   /* 3FD24924 94229359 */
+		L4    = 2.222219843214978396e-01   /* 3FCC71C5 1D8E78AF */
+		L5    = 1.818357216161805012e-01   /* 3FC74664 96CB03DE */
+		L6    = 1.531383769920937332e-01   /* 3FC39A09 D078C69F */
+		L7    = 1.479819860511658591e-01   /* 3FC2F112 DF3E5244 */
+	)
+
+	// special cases
+	switch {
+	case IsNaN(x) || IsInf(x, 1):
+		return x
+	case x < 0:
+		return NaN()
+	case x == 0:
+		return Inf(-1)
+	}
+
+	// reduce
+	f1, ki := Frexp(x)
+	if f1 < Sqrt2/2 {
+		f1 *= 2
+		ki--
+	}
+	f := f1 - 1
+	k := float64(ki)
+
+	// compute
+	s := f / (2 + f)
+	s2 := s * s
+	s4 := s2 * s2
+	t1 := s2 * (L1 + s4*(L3+s4*(L5+s4*L7)))
+	t2 := s4 * (L2 + s4*(L4+s4*L6))
+	R := t1 + t2
+	hfsq := 0.5 * f * f
+	return k*Ln2Hi - ((hfsq - (s*(hfsq+R) + k*Ln2Lo)) - f)
+}
diff --git a/contrib/go/_std_1.18/src/math/log10.go b/contrib/go/_std_1.19/src/math/log10.go
index e6916a53b6..e6916a53b6 100644
--- a/contrib/go/_std_1.18/src/math/log10.go
+++ b/contrib/go/_std_1.19/src/math/log10.go
diff --git a/contrib/go/_std_1.19/src/math/log1p.go b/contrib/go/_std_1.19/src/math/log1p.go
new file mode 100644
index 0000000000..3a7b3854a8
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/log1p.go
@@ -0,0 +1,203 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// The original C code, the long comment, and the constants
+// below are from FreeBSD's /usr/src/lib/msun/src/s_log1p.c
+// and came with this notice. The go code is a simplified
+// version of the original C.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+//
+// double log1p(double x)
+//
+// Method :
+//   1. Argument Reduction: find k and f such that
+//                      1+x = 2**k * (1+f),
+//         where  sqrt(2)/2 < 1+f < sqrt(2) .
+//
+//      Note. If k=0, then f=x is exact. However, if k!=0, then f
+//      may not be representable exactly. In that case, a correction
+//      term is need. Let u=1+x rounded. Let c = (1+x)-u, then
+//      log(1+x) - log(u) ~ c/u. Thus, we proceed to compute log(u),
+//      and add back the correction term c/u.
+//      (Note: when x > 2**53, one can simply return log(x))
+//
+//   2. Approximation of log1p(f).
+//      Let s = f/(2+f) ; based on log(1+f) = log(1+s) - log(1-s)
+//               = 2s + 2/3 s**3 + 2/5 s**5 + .....,
+//               = 2s + s*R
+//      We use a special Reme algorithm on [0,0.1716] to generate
+//      a polynomial of degree 14 to approximate R The maximum error
+//      of this polynomial approximation is bounded by 2**-58.45. In
+//      other words,
+//                      2      4      6      8      10      12      14
+//          R(z) ~ Lp1*s +Lp2*s +Lp3*s +Lp4*s +Lp5*s  +Lp6*s  +Lp7*s
+//      (the values of Lp1 to Lp7 are listed in the program)
+//      and
+//          |      2          14          |     -58.45
+//          | Lp1*s +...+Lp7*s    -  R(z) | <= 2
+//          |                             |
+//      Note that 2s = f - s*f = f - hfsq + s*hfsq, where hfsq = f*f/2.
+//      In order to guarantee error in log below 1ulp, we compute log
+//      by
+//              log1p(f) = f - (hfsq - s*(hfsq+R)).
+//
+//   3. Finally, log1p(x) = k*ln2 + log1p(f).
+//                        = k*ln2_hi+(f-(hfsq-(s*(hfsq+R)+k*ln2_lo)))
+//      Here ln2 is split into two floating point number:
+//                   ln2_hi + ln2_lo,
+//      where n*ln2_hi is always exact for |n| < 2000.
+//
+// Special cases:
+//      log1p(x) is NaN with signal if x < -1 (including -INF) ;
+//      log1p(+INF) is +INF; log1p(-1) is -INF with signal;
+//      log1p(NaN) is that NaN with no signal.
+//
+// Accuracy:
+//      according to an error analysis, the error is always less than
+//      1 ulp (unit in the last place).
+//
+// Constants:
+// The hexadecimal values are the intended ones for the following
+// constants. The decimal values may be used, provided that the
+// compiler will convert from decimal to binary accurately enough
+// to produce the hexadecimal values shown.
+//
+// Note: Assuming log() return accurate answer, the following
+//       algorithm can be used to compute log1p(x) to within a few ULP:
+//
+//              u = 1+x;
+//              if(u==1.0) return x ; else
+//                         return log(u)*(x/(u-1.0));
+//
+//       See HP-15C Advanced Functions Handbook, p.193.
+
+// Log1p returns the natural logarithm of 1 plus its argument x.
+// It is more accurate than Log(1 + x) when x is near zero.
+//
+// Special cases are:
+//
+//	Log1p(+Inf) = +Inf
+//	Log1p(±0) = ±0
+//	Log1p(-1) = -Inf
+//	Log1p(x < -1) = NaN
+//	Log1p(NaN) = NaN
+func Log1p(x float64) float64 {
+	if haveArchLog1p {
+		return archLog1p(x)
+	}
+	return log1p(x)
+}
+
+func log1p(x float64) float64 {
+	const (
+		Sqrt2M1     = 4.142135623730950488017e-01  // Sqrt(2)-1 = 0x3fda827999fcef34
+		Sqrt2HalfM1 = -2.928932188134524755992e-01 // Sqrt(2)/2-1 = 0xbfd2bec333018866
+		Small       = 1.0 / (1 << 29)              // 2**-29 = 0x3e20000000000000
+		Tiny        = 1.0 / (1 << 54)              // 2**-54
+		Two53       = 1 << 53                      // 2**53
+		Ln2Hi       = 6.93147180369123816490e-01   // 3fe62e42fee00000
+		Ln2Lo       = 1.90821492927058770002e-10   // 3dea39ef35793c76
+		Lp1         = 6.666666666666735130e-01     // 3FE5555555555593
+		Lp2         = 3.999999999940941908e-01     // 3FD999999997FA04
+		Lp3         = 2.857142874366239149e-01     // 3FD2492494229359
+		Lp4         = 2.222219843214978396e-01     // 3FCC71C51D8E78AF
+		Lp5         = 1.818357216161805012e-01     // 3FC7466496CB03DE
+		Lp6         = 1.531383769920937332e-01     // 3FC39A09D078C69F
+		Lp7         = 1.479819860511658591e-01     // 3FC2F112DF3E5244
+	)
+
+	// special cases
+	switch {
+	case x < -1 || IsNaN(x): // includes -Inf
+		return NaN()
+	case x == -1:
+		return Inf(-1)
+	case IsInf(x, 1):
+		return Inf(1)
+	}
+
+	absx := Abs(x)
+
+	var f float64
+	var iu uint64
+	k := 1
+	if absx < Sqrt2M1 { //  |x| < Sqrt(2)-1
+		if absx < Small { // |x| < 2**-29
+			if absx < Tiny { // |x| < 2**-54
+				return x
+			}
+			return x - x*x*0.5
+		}
+		if x > Sqrt2HalfM1 { // Sqrt(2)/2-1 < x
+			// (Sqrt(2)/2-1) < x < (Sqrt(2)-1)
+			k = 0
+			f = x
+			iu = 1
+		}
+	}
+	var c float64
+	if k != 0 {
+		var u float64
+		if absx < Two53 { // 1<<53
+			u = 1.0 + x
+			iu = Float64bits(u)
+			k = int((iu >> 52) - 1023)
+			// correction term
+			if k > 0 {
+				c = 1.0 - (u - x)
+			} else {
+				c = x - (u - 1.0)
+			}
+			c /= u
+		} else {
+			u = x
+			iu = Float64bits(u)
+			k = int((iu >> 52) - 1023)
+			c = 0
+		}
+		iu &= 0x000fffffffffffff
+		if iu < 0x0006a09e667f3bcd { // mantissa of Sqrt(2)
+			u = Float64frombits(iu | 0x3ff0000000000000) // normalize u
+		} else {
+			k++
+			u = Float64frombits(iu | 0x3fe0000000000000) // normalize u/2
+			iu = (0x0010000000000000 - iu) >> 2
+		}
+		f = u - 1.0 // Sqrt(2)/2 < u < Sqrt(2)
+	}
+	hfsq := 0.5 * f * f
+	var s, R, z float64
+	if iu == 0 { // |f| < 2**-20
+		if f == 0 {
+			if k == 0 {
+				return 0
+			}
+			c += float64(k) * Ln2Lo
+			return float64(k)*Ln2Hi + c
+		}
+		R = hfsq * (1.0 - 0.66666666666666666*f) // avoid division
+		if k == 0 {
+			return f - R
+		}
+		return float64(k)*Ln2Hi - ((R - (float64(k)*Ln2Lo + c)) - f)
+	}
+	s = f / (2.0 + f)
+	z = s * s
+	R = z * (Lp1 + z*(Lp2+z*(Lp3+z*(Lp4+z*(Lp5+z*(Lp6+z*Lp7))))))
+	if k == 0 {
+		return f - (hfsq - s*(hfsq+R))
+	}
+	return float64(k)*Ln2Hi - ((hfsq - (s*(hfsq+R) + (float64(k)*Ln2Lo + c))) - f)
+}
diff --git a/contrib/go/_std_1.18/src/math/log_amd64.s b/contrib/go/_std_1.19/src/math/log_amd64.s
index d84091f23a..d84091f23a 100644
--- a/contrib/go/_std_1.18/src/math/log_amd64.s
+++ b/contrib/go/_std_1.19/src/math/log_amd64.s
diff --git a/contrib/go/_std_1.18/src/math/log_asm.go b/contrib/go/_std_1.19/src/math/log_asm.go
index 848cce13b2..848cce13b2 100644
--- a/contrib/go/_std_1.18/src/math/log_asm.go
+++ b/contrib/go/_std_1.19/src/math/log_asm.go
diff --git a/contrib/go/_std_1.19/src/math/logb.go b/contrib/go/_std_1.19/src/math/logb.go
new file mode 100644
index 0000000000..04ba3e968e
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/logb.go
@@ -0,0 +1,52 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Logb returns the binary exponent of x.
+//
+// Special cases are:
+//
+//	Logb(±Inf) = +Inf
+//	Logb(0) = -Inf
+//	Logb(NaN) = NaN
+func Logb(x float64) float64 {
+	// special cases
+	switch {
+	case x == 0:
+		return Inf(-1)
+	case IsInf(x, 0):
+		return Inf(1)
+	case IsNaN(x):
+		return x
+	}
+	return float64(ilogb(x))
+}
+
+// Ilogb returns the binary exponent of x as an integer.
+//
+// Special cases are:
+//
+//	Ilogb(±Inf) = MaxInt32
+//	Ilogb(0) = MinInt32
+//	Ilogb(NaN) = MaxInt32
+func Ilogb(x float64) int {
+	// special cases
+	switch {
+	case x == 0:
+		return MinInt32
+	case IsNaN(x):
+		return MaxInt32
+	case IsInf(x, 0):
+		return MaxInt32
+	}
+	return ilogb(x)
+}
+
+// logb returns the binary exponent of x. It assumes x is finite and
+// non-zero.
+func ilogb(x float64) int {
+	x, exp := normalize(x)
+	return int((Float64bits(x)>>shift)&mask) - bias + exp
+}
diff --git a/contrib/go/_std_1.19/src/math/mod.go b/contrib/go/_std_1.19/src/math/mod.go
new file mode 100644
index 0000000000..6f24250cfb
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/mod.go
@@ -0,0 +1,52 @@
+// Copyright 2009-2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+	Floating-point mod function.
+*/
+
+// Mod returns the floating-point remainder of x/y.
+// The magnitude of the result is less than y and its
+// sign agrees with that of x.
+//
+// Special cases are:
+//
+//	Mod(±Inf, y) = NaN
+//	Mod(NaN, y) = NaN
+//	Mod(x, 0) = NaN
+//	Mod(x, ±Inf) = x
+//	Mod(x, NaN) = NaN
+func Mod(x, y float64) float64 {
+	if haveArchMod {
+		return archMod(x, y)
+	}
+	return mod(x, y)
+}
+
+func mod(x, y float64) float64 {
+	if y == 0 || IsInf(x, 0) || IsNaN(x) || IsNaN(y) {
+		return NaN()
+	}
+	y = Abs(y)
+
+	yfr, yexp := Frexp(y)
+	r := x
+	if x < 0 {
+		r = -x
+	}
+
+	for r >= y {
+		rfr, rexp := Frexp(r)
+		if rfr < yfr {
+			rexp = rexp - 1
+		}
+		r = r - Ldexp(y, rexp-yexp)
+	}
+	if x < 0 {
+		r = -r
+	}
+	return r
+}
diff --git a/contrib/go/_std_1.19/src/math/modf.go b/contrib/go/_std_1.19/src/math/modf.go
new file mode 100644
index 0000000000..613a75fc9a
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/modf.go
@@ -0,0 +1,43 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Modf returns integer and fractional floating-point numbers
+// that sum to f. Both values have the same sign as f.
+//
+// Special cases are:
+//
+//	Modf(±Inf) = ±Inf, NaN
+//	Modf(NaN) = NaN, NaN
+func Modf(f float64) (int float64, frac float64) {
+	if haveArchModf {
+		return archModf(f)
+	}
+	return modf(f)
+}
+
+func modf(f float64) (int float64, frac float64) {
+	if f < 1 {
+		switch {
+		case f < 0:
+			int, frac = Modf(-f)
+			return -int, -frac
+		case f == 0:
+			return f, f // Return -0, -0 when f == -0
+		}
+		return 0, f
+	}
+
+	x := Float64bits(f)
+	e := uint(x>>shift)&mask - bias
+
+	// Keep the top 12+e bits, the integer part; clear the rest.
+	if e < 64-12 {
+		x &^= 1<<(64-12-e) - 1
+	}
+	int = Float64frombits(x)
+	frac = f - int
+	return
+}
diff --git a/contrib/go/_std_1.18/src/math/modf_noasm.go b/contrib/go/_std_1.19/src/math/modf_noasm.go
index 55c6a7f6e2..55c6a7f6e2 100644
--- a/contrib/go/_std_1.18/src/math/modf_noasm.go
+++ b/contrib/go/_std_1.19/src/math/modf_noasm.go
diff --git a/contrib/go/_std_1.19/src/math/nextafter.go b/contrib/go/_std_1.19/src/math/nextafter.go
new file mode 100644
index 0000000000..ec18d542d9
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/nextafter.go
@@ -0,0 +1,51 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Nextafter32 returns the next representable float32 value after x towards y.
+//
+// Special cases are:
+//
+//	Nextafter32(x, x)   = x
+//	Nextafter32(NaN, y) = NaN
+//	Nextafter32(x, NaN) = NaN
+func Nextafter32(x, y float32) (r float32) {
+	switch {
+	case IsNaN(float64(x)) || IsNaN(float64(y)): // special case
+		r = float32(NaN())
+	case x == y:
+		r = x
+	case x == 0:
+		r = float32(Copysign(float64(Float32frombits(1)), float64(y)))
+	case (y > x) == (x > 0):
+		r = Float32frombits(Float32bits(x) + 1)
+	default:
+		r = Float32frombits(Float32bits(x) - 1)
+	}
+	return
+}
+
+// Nextafter returns the next representable float64 value after x towards y.
+//
+// Special cases are:
+//
+//	Nextafter(x, x)   = x
+//	Nextafter(NaN, y) = NaN
+//	Nextafter(x, NaN) = NaN
+func Nextafter(x, y float64) (r float64) {
+	switch {
+	case IsNaN(x) || IsNaN(y): // special case
+		r = NaN()
+	case x == y:
+		r = x
+	case x == 0:
+		r = Copysign(Float64frombits(1), y)
+	case (y > x) == (x > 0):
+		r = Float64frombits(Float64bits(x) + 1)
+	default:
+		r = Float64frombits(Float64bits(x) - 1)
+	}
+	return
+}
diff --git a/contrib/go/_std_1.19/src/math/pow.go b/contrib/go/_std_1.19/src/math/pow.go
new file mode 100644
index 0000000000..3af8c8b649
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/pow.go
@@ -0,0 +1,157 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+func isOddInt(x float64) bool {
+	xi, xf := Modf(x)
+	return xf == 0 && int64(xi)&1 == 1
+}
+
+// Special cases taken from FreeBSD's /usr/src/lib/msun/src/e_pow.c
+// updated by IEEE Std. 754-2008 "Section 9.2.1 Special values".
+
+// Pow returns x**y, the base-x exponential of y.
+//
+// Special cases are (in order):
+//
+//	Pow(x, ±0) = 1 for any x
+//	Pow(1, y) = 1 for any y
+//	Pow(x, 1) = x for any x
+//	Pow(NaN, y) = NaN
+//	Pow(x, NaN) = NaN
+//	Pow(±0, y) = ±Inf for y an odd integer < 0
+//	Pow(±0, -Inf) = +Inf
+//	Pow(±0, +Inf) = +0
+//	Pow(±0, y) = +Inf for finite y < 0 and not an odd integer
+//	Pow(±0, y) = ±0 for y an odd integer > 0
+//	Pow(±0, y) = +0 for finite y > 0 and not an odd integer
+//	Pow(-1, ±Inf) = 1
+//	Pow(x, +Inf) = +Inf for |x| > 1
+//	Pow(x, -Inf) = +0 for |x| > 1
+//	Pow(x, +Inf) = +0 for |x| < 1
+//	Pow(x, -Inf) = +Inf for |x| < 1
+//	Pow(+Inf, y) = +Inf for y > 0
+//	Pow(+Inf, y) = +0 for y < 0
+//	Pow(-Inf, y) = Pow(-0, -y)
+//	Pow(x, y) = NaN for finite x < 0 and finite non-integer y
+func Pow(x, y float64) float64 {
+	if haveArchPow {
+		return archPow(x, y)
+	}
+	return pow(x, y)
+}
+
+func pow(x, y float64) float64 {
+	switch {
+	case y == 0 || x == 1:
+		return 1
+	case y == 1:
+		return x
+	case IsNaN(x) || IsNaN(y):
+		return NaN()
+	case x == 0:
+		switch {
+		case y < 0:
+			if isOddInt(y) {
+				return Copysign(Inf(1), x)
+			}
+			return Inf(1)
+		case y > 0:
+			if isOddInt(y) {
+				return x
+			}
+			return 0
+		}
+	case IsInf(y, 0):
+		switch {
+		case x == -1:
+			return 1
+		case (Abs(x) < 1) == IsInf(y, 1):
+			return 0
+		default:
+			return Inf(1)
+		}
+	case IsInf(x, 0):
+		if IsInf(x, -1) {
+			return Pow(1/x, -y) // Pow(-0, -y)
+		}
+		switch {
+		case y < 0:
+			return 0
+		case y > 0:
+			return Inf(1)
+		}
+	case y == 0.5:
+		return Sqrt(x)
+	case y == -0.5:
+		return 1 / Sqrt(x)
+	}
+
+	yi, yf := Modf(Abs(y))
+	if yf != 0 && x < 0 {
+		return NaN()
+	}
+	if yi >= 1<<63 {
+		// yi is a large even int that will lead to overflow (or underflow to 0)
+		// for all x except -1 (x == 1 was handled earlier)
+		switch {
+		case x == -1:
+			return 1
+		case (Abs(x) < 1) == (y > 0):
+			return 0
+		default:
+			return Inf(1)
+		}
+	}
+
+	// ans = a1 * 2**ae (= 1 for now).
+	a1 := 1.0
+	ae := 0
+
+	// ans *= x**yf
+	if yf != 0 {
+		if yf > 0.5 {
+			yf--
+			yi++
+		}
+		a1 = Exp(yf * Log(x))
+	}
+
+	// ans *= x**yi
+	// by multiplying in successive squarings
+	// of x according to bits of yi.
+	// accumulate powers of two into exp.
+	x1, xe := Frexp(x)
+	for i := int64(yi); i != 0; i >>= 1 {
+		if xe < -1<<12 || 1<<12 < xe {
+			// catch xe before it overflows the left shift below
+			// Since i !=0 it has at least one bit still set, so ae will accumulate xe
+			// on at least one more iteration, ae += xe is a lower bound on ae
+			// the lower bound on ae exceeds the size of a float64 exp
+			// so the final call to Ldexp will produce under/overflow (0/Inf)
+			ae += xe
+			break
+		}
+		if i&1 == 1 {
+			a1 *= x1
+			ae += xe
+		}
+		x1 *= x1
+		xe <<= 1
+		if x1 < .5 {
+			x1 += x1
+			xe--
+		}
+	}
+
+	// ans = a1*2**ae
+	// if y < 0 { ans = 1 / ans }
+	// but in the opposite order
+	if y < 0 {
+		a1 = 1 / a1
+		ae = -ae
+	}
+	return Ldexp(a1, ae)
+}
diff --git a/contrib/go/_std_1.19/src/math/pow10.go b/contrib/go/_std_1.19/src/math/pow10.go
new file mode 100644
index 0000000000..c31ad8dbc7
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/pow10.go
@@ -0,0 +1,47 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// pow10tab stores the pre-computed values 10**i for i < 32.
+var pow10tab = [...]float64{
+	1e00, 1e01, 1e02, 1e03, 1e04, 1e05, 1e06, 1e07, 1e08, 1e09,
+	1e10, 1e11, 1e12, 1e13, 1e14, 1e15, 1e16, 1e17, 1e18, 1e19,
+	1e20, 1e21, 1e22, 1e23, 1e24, 1e25, 1e26, 1e27, 1e28, 1e29,
+	1e30, 1e31,
+}
+
+// pow10postab32 stores the pre-computed value for 10**(i*32) at index i.
+var pow10postab32 = [...]float64{
+	1e00, 1e32, 1e64, 1e96, 1e128, 1e160, 1e192, 1e224, 1e256, 1e288,
+}
+
+// pow10negtab32 stores the pre-computed value for 10**(-i*32) at index i.
+var pow10negtab32 = [...]float64{
+	1e-00, 1e-32, 1e-64, 1e-96, 1e-128, 1e-160, 1e-192, 1e-224, 1e-256, 1e-288, 1e-320,
+}
+
+// Pow10 returns 10**n, the base-10 exponential of n.
+//
+// Special cases are:
+//
+//	Pow10(n) =    0 for n < -323
+//	Pow10(n) = +Inf for n > 308
+func Pow10(n int) float64 {
+	if 0 <= n && n <= 308 {
+		return pow10postab32[uint(n)/32] * pow10tab[uint(n)%32]
+	}
+
+	if -323 <= n && n <= 0 {
+		return pow10negtab32[uint(-n)/32] / pow10tab[uint(-n)%32]
+	}
+
+	// n < -323 || 308 < n
+	if n > 0 {
+		return Inf(1)
+	}
+
+	// n < -323
+	return 0
+}
diff --git a/contrib/go/_std_1.19/src/math/rand/exp.go b/contrib/go/_std_1.19/src/math/rand/exp.go
new file mode 100644
index 0000000000..c1162c19b6
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/rand/exp.go
@@ -0,0 +1,221 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package rand
+
+import (
+	"math"
+)
+
+/*
+ * Exponential distribution
+ *
+ * See "The Ziggurat Method for Generating Random Variables"
+ * (Marsaglia & Tsang, 2000)
+ * https://www.jstatsoft.org/v05/i08/paper [pdf]
+ */
+
+const (
+	re = 7.69711747013104972
+)
+
+// ExpFloat64 returns an exponentially distributed float64 in the range
+// (0, +math.MaxFloat64] with an exponential distribution whose rate parameter
+// (lambda) is 1 and whose mean is 1/lambda (1).
+// To produce a distribution with a different rate parameter,
+// callers can adjust the output using:
+//
+//	sample = ExpFloat64() / desiredRateParameter
+func (r *Rand) ExpFloat64() float64 {
+	for {
+		j := r.Uint32()
+		i := j & 0xFF
+		x := float64(j) * float64(we[i])
+		if j < ke[i] {
+			return x
+		}
+		if i == 0 {
+			return re - math.Log(r.Float64())
+		}
+		if fe[i]+float32(r.Float64())*(fe[i-1]-fe[i]) < float32(math.Exp(-x)) {
+			return x
+		}
+	}
+}
+
+var ke = [256]uint32{
+	0xe290a139, 0x0, 0x9beadebc, 0xc377ac71, 0xd4ddb990,
+	0xde893fb8, 0xe4a8e87c, 0xe8dff16a, 0xebf2deab, 0xee49a6e8,
+	0xf0204efd, 0xf19bdb8e, 0xf2d458bb, 0xf3da104b, 0xf4b86d78,
+	0xf577ad8a, 0xf61de83d, 0xf6afb784, 0xf730a573, 0xf7a37651,
+	0xf80a5bb6, 0xf867189d, 0xf8bb1b4f, 0xf9079062, 0xf94d70ca,
+	0xf98d8c7d, 0xf9c8928a, 0xf9ff175b, 0xfa319996, 0xfa6085f8,
+	0xfa8c3a62, 0xfab5084e, 0xfadb36c8, 0xfaff0410, 0xfb20a6ea,
+	0xfb404fb4, 0xfb5e2951, 0xfb7a59e9, 0xfb95038c, 0xfbae44ba,
+	0xfbc638d8, 0xfbdcf892, 0xfbf29a30, 0xfc0731df, 0xfc1ad1ed,
+	0xfc2d8b02, 0xfc3f6c4d, 0xfc5083ac, 0xfc60ddd1, 0xfc708662,
+	0xfc7f8810, 0xfc8decb4, 0xfc9bbd62, 0xfca9027c, 0xfcb5c3c3,
+	0xfcc20864, 0xfccdd70a, 0xfcd935e3, 0xfce42ab0, 0xfceebace,
+	0xfcf8eb3b, 0xfd02c0a0, 0xfd0c3f59, 0xfd156b7b, 0xfd1e48d6,
+	0xfd26daff, 0xfd2f2552, 0xfd372af7, 0xfd3eeee5, 0xfd4673e7,
+	0xfd4dbc9e, 0xfd54cb85, 0xfd5ba2f2, 0xfd62451b, 0xfd68b415,
+	0xfd6ef1da, 0xfd750047, 0xfd7ae120, 0xfd809612, 0xfd8620b4,
+	0xfd8b8285, 0xfd90bcf5, 0xfd95d15e, 0xfd9ac10b, 0xfd9f8d36,
+	0xfda43708, 0xfda8bf9e, 0xfdad2806, 0xfdb17141, 0xfdb59c46,
+	0xfdb9a9fd, 0xfdbd9b46, 0xfdc170f6, 0xfdc52bd8, 0xfdc8ccac,
+	0xfdcc542d, 0xfdcfc30b, 0xfdd319ef, 0xfdd6597a, 0xfdd98245,
+	0xfddc94e5, 0xfddf91e6, 0xfde279ce, 0xfde54d1f, 0xfde80c52,
+	0xfdeab7de, 0xfded5034, 0xfdefd5be, 0xfdf248e3, 0xfdf4aa06,
+	0xfdf6f984, 0xfdf937b6, 0xfdfb64f4, 0xfdfd818d, 0xfdff8dd0,
+	0xfe018a08, 0xfe03767a, 0xfe05536c, 0xfe07211c, 0xfe08dfc9,
+	0xfe0a8fab, 0xfe0c30fb, 0xfe0dc3ec, 0xfe0f48b1, 0xfe10bf76,
+	0xfe122869, 0xfe1383b4, 0xfe14d17c, 0xfe1611e7, 0xfe174516,
+	0xfe186b2a, 0xfe19843e, 0xfe1a9070, 0xfe1b8fd6, 0xfe1c8289,
+	0xfe1d689b, 0xfe1e4220, 0xfe1f0f26, 0xfe1fcfbc, 0xfe2083ed,
+	0xfe212bc3, 0xfe21c745, 0xfe225678, 0xfe22d95f, 0xfe234ffb,
+	0xfe23ba4a, 0xfe241849, 0xfe2469f2, 0xfe24af3c, 0xfe24e81e,
+	0xfe25148b, 0xfe253474, 0xfe2547c7, 0xfe254e70, 0xfe25485a,
+	0xfe25356a, 0xfe251586, 0xfe24e88f, 0xfe24ae64, 0xfe2466e1,
+	0xfe2411df, 0xfe23af34, 0xfe233eb4, 0xfe22c02c, 0xfe22336b,
+	0xfe219838, 0xfe20ee58, 0xfe20358c, 0xfe1f6d92, 0xfe1e9621,
+	0xfe1daef0, 0xfe1cb7ac, 0xfe1bb002, 0xfe1a9798, 0xfe196e0d,
+	0xfe1832fd, 0xfe16e5fe, 0xfe15869d, 0xfe141464, 0xfe128ed3,
+	0xfe10f565, 0xfe0f478c, 0xfe0d84b1, 0xfe0bac36, 0xfe09bd73,
+	0xfe07b7b5, 0xfe059a40, 0xfe03644c, 0xfe011504, 0xfdfeab88,
+	0xfdfc26e9, 0xfdf98629, 0xfdf6c83b, 0xfdf3ec01, 0xfdf0f04a,
+	0xfdedd3d1, 0xfdea953d, 0xfde7331e, 0xfde3abe9, 0xfddffdfb,
+	0xfddc2791, 0xfdd826cd, 0xfdd3f9a8, 0xfdcf9dfc, 0xfdcb1176,
+	0xfdc65198, 0xfdc15bb3, 0xfdbc2ce2, 0xfdb6c206, 0xfdb117be,
+	0xfdab2a63, 0xfda4f5fd, 0xfd9e7640, 0xfd97a67a, 0xfd908192,
+	0xfd8901f2, 0xfd812182, 0xfd78d98e, 0xfd7022bb, 0xfd66f4ed,
+	0xfd5d4732, 0xfd530f9c, 0xfd48432b, 0xfd3cd59a, 0xfd30b936,
+	0xfd23dea4, 0xfd16349e, 0xfd07a7a3, 0xfcf8219b, 0xfce7895b,
+	0xfcd5c220, 0xfcc2aadb, 0xfcae1d5e, 0xfc97ed4e, 0xfc7fe6d4,
+	0xfc65ccf3, 0xfc495762, 0xfc2a2fc8, 0xfc07ee19, 0xfbe213c1,
+	0xfbb8051a, 0xfb890078, 0xfb5411a5, 0xfb180005, 0xfad33482,
+	0xfa839276, 0xfa263b32, 0xf9b72d1c, 0xf930a1a2, 0xf889f023,
+	0xf7b577d2, 0xf69c650c, 0xf51530f0, 0xf2cb0e3c, 0xeeefb15d,
+	0xe6da6ecf,
+}
+var we = [256]float32{
+	2.0249555e-09, 1.486674e-11, 2.4409617e-11, 3.1968806e-11,
+	3.844677e-11, 4.4228204e-11, 4.9516443e-11, 5.443359e-11,
+	5.905944e-11, 6.344942e-11, 6.7643814e-11, 7.1672945e-11,
+	7.556032e-11, 7.932458e-11, 8.298079e-11, 8.654132e-11,
+	9.0016515e-11, 9.3415074e-11, 9.674443e-11, 1.0001099e-10,
+	1.03220314e-10, 1.06377254e-10, 1.09486115e-10, 1.1255068e-10,
+	1.1557435e-10, 1.1856015e-10, 1.2151083e-10, 1.2442886e-10,
+	1.2731648e-10, 1.3017575e-10, 1.3300853e-10, 1.3581657e-10,
+	1.3860142e-10, 1.4136457e-10, 1.4410738e-10, 1.4683108e-10,
+	1.4953687e-10, 1.5222583e-10, 1.54899e-10, 1.5755733e-10,
+	1.6020171e-10, 1.6283301e-10, 1.6545203e-10, 1.6805951e-10,
+	1.7065617e-10, 1.732427e-10, 1.7581973e-10, 1.7838787e-10,
+	1.8094774e-10, 1.8349985e-10, 1.8604476e-10, 1.8858298e-10,
+	1.9111498e-10, 1.9364126e-10, 1.9616223e-10, 1.9867835e-10,
+	2.0119004e-10, 2.0369768e-10, 2.0620168e-10, 2.087024e-10,
+	2.1120022e-10, 2.136955e-10, 2.1618855e-10, 2.1867974e-10,
+	2.2116936e-10, 2.2365775e-10, 2.261452e-10, 2.2863202e-10,
+	2.311185e-10, 2.3360494e-10, 2.360916e-10, 2.3857874e-10,
+	2.4106667e-10, 2.4355562e-10, 2.4604588e-10, 2.485377e-10,
+	2.5103128e-10, 2.5352695e-10, 2.560249e-10, 2.585254e-10,
+	2.6102867e-10, 2.6353494e-10, 2.6604446e-10, 2.6855745e-10,
+	2.7107416e-10, 2.7359479e-10, 2.761196e-10, 2.7864877e-10,
+	2.8118255e-10, 2.8372119e-10, 2.8626485e-10, 2.888138e-10,
+	2.9136826e-10, 2.939284e-10, 2.9649452e-10, 2.9906677e-10,
+	3.016454e-10, 3.0423064e-10, 3.0682268e-10, 3.0942177e-10,
+	3.1202813e-10, 3.1464195e-10, 3.1726352e-10, 3.19893e-10,
+	3.2253064e-10, 3.251767e-10, 3.2783135e-10, 3.3049485e-10,
+	3.3316744e-10, 3.3584938e-10, 3.3854083e-10, 3.4124212e-10,
+	3.4395342e-10, 3.46675e-10, 3.4940711e-10, 3.5215003e-10,
+	3.5490397e-10, 3.5766917e-10, 3.6044595e-10, 3.6323455e-10,
+	3.660352e-10, 3.6884823e-10, 3.7167386e-10, 3.745124e-10,
+	3.773641e-10, 3.802293e-10, 3.8310827e-10, 3.860013e-10,
+	3.8890866e-10, 3.918307e-10, 3.9476775e-10, 3.9772008e-10,
+	4.0068804e-10, 4.0367196e-10, 4.0667217e-10, 4.09689e-10,
+	4.1272286e-10, 4.1577405e-10, 4.1884296e-10, 4.2192994e-10,
+	4.250354e-10, 4.281597e-10, 4.313033e-10, 4.3446652e-10,
+	4.3764986e-10, 4.408537e-10, 4.4407847e-10, 4.4732465e-10,
+	4.5059267e-10, 4.5388301e-10, 4.571962e-10, 4.6053267e-10,
+	4.6389292e-10, 4.6727755e-10, 4.70687e-10, 4.741219e-10,
+	4.7758275e-10, 4.810702e-10, 4.845848e-10, 4.8812715e-10,
+	4.9169796e-10, 4.9529775e-10, 4.989273e-10, 5.0258725e-10,
+	5.0627835e-10, 5.100013e-10, 5.1375687e-10, 5.1754584e-10,
+	5.21369e-10, 5.2522725e-10, 5.2912136e-10, 5.330522e-10,
+	5.370208e-10, 5.4102806e-10, 5.45075e-10, 5.491625e-10,
+	5.532918e-10, 5.5746385e-10, 5.616799e-10, 5.6594107e-10,
+	5.7024857e-10, 5.746037e-10, 5.7900773e-10, 5.834621e-10,
+	5.8796823e-10, 5.925276e-10, 5.971417e-10, 6.018122e-10,
+	6.065408e-10, 6.113292e-10, 6.1617933e-10, 6.2109295e-10,
+	6.260722e-10, 6.3111916e-10, 6.3623595e-10, 6.4142497e-10,
+	6.4668854e-10, 6.5202926e-10, 6.5744976e-10, 6.6295286e-10,
+	6.6854156e-10, 6.742188e-10, 6.79988e-10, 6.858526e-10,
+	6.9181616e-10, 6.978826e-10, 7.04056e-10, 7.103407e-10,
+	7.167412e-10, 7.2326256e-10, 7.2990985e-10, 7.366886e-10,
+	7.4360473e-10, 7.5066453e-10, 7.5787476e-10, 7.6524265e-10,
+	7.7277595e-10, 7.80483e-10, 7.883728e-10, 7.9645507e-10,
+	8.047402e-10, 8.1323964e-10, 8.219657e-10, 8.309319e-10,
+	8.401528e-10, 8.496445e-10, 8.594247e-10, 8.6951274e-10,
+	8.799301e-10, 8.9070046e-10, 9.018503e-10, 9.134092e-10,
+	9.254101e-10, 9.378904e-10, 9.508923e-10, 9.644638e-10,
+	9.786603e-10, 9.935448e-10, 1.0091913e-09, 1.025686e-09,
+	1.0431306e-09, 1.0616465e-09, 1.08138e-09, 1.1025096e-09,
+	1.1252564e-09, 1.1498986e-09, 1.1767932e-09, 1.206409e-09,
+	1.2393786e-09, 1.276585e-09, 1.3193139e-09, 1.3695435e-09,
+	1.4305498e-09, 1.508365e-09, 1.6160854e-09, 1.7921248e-09,
+}
+var fe = [256]float32{
+	1, 0.9381437, 0.90046996, 0.87170434, 0.8477855, 0.8269933,
+	0.8084217, 0.7915276, 0.77595687, 0.7614634, 0.7478686,
+	0.7350381, 0.72286767, 0.71127474, 0.70019263, 0.6895665,
+	0.67935055, 0.6695063, 0.66000086, 0.65080583, 0.6418967,
+	0.63325197, 0.6248527, 0.6166822, 0.60872537, 0.60096896,
+	0.5934009, 0.58601034, 0.5787874, 0.57172304, 0.5648092,
+	0.5580383, 0.5514034, 0.5448982, 0.5385169, 0.53225386,
+	0.5261042, 0.52006316, 0.5141264, 0.50828975, 0.5025495,
+	0.496902, 0.49134386, 0.485872, 0.48048335, 0.4751752,
+	0.46994483, 0.46478975, 0.45970762, 0.45469615, 0.44975325,
+	0.44487688, 0.44006512, 0.43531612, 0.43062815, 0.42599955,
+	0.42142874, 0.4169142, 0.41245446, 0.40804818, 0.403694,
+	0.3993907, 0.39513698, 0.39093173, 0.38677382, 0.38266218,
+	0.37859577, 0.37457356, 0.37059465, 0.3666581, 0.362763,
+	0.35890847, 0.35509375, 0.351318, 0.3475805, 0.34388044,
+	0.34021714, 0.3365899, 0.33299807, 0.32944095, 0.32591796,
+	0.3224285, 0.3189719, 0.31554767, 0.31215525, 0.30879408,
+	0.3054636, 0.3021634, 0.29889292, 0.2956517, 0.29243928,
+	0.28925523, 0.28609908, 0.28297043, 0.27986884, 0.27679393,
+	0.2737453, 0.2707226, 0.2677254, 0.26475343, 0.26180625,
+	0.25888354, 0.25598502, 0.2531103, 0.25025907, 0.24743107,
+	0.24462597, 0.24184346, 0.23908329, 0.23634516, 0.23362878,
+	0.23093392, 0.2282603, 0.22560766, 0.22297576, 0.22036438,
+	0.21777324, 0.21520215, 0.21265087, 0.21011916, 0.20760682,
+	0.20511365, 0.20263945, 0.20018397, 0.19774707, 0.19532852,
+	0.19292815, 0.19054577, 0.1881812, 0.18583426, 0.18350479,
+	0.1811926, 0.17889754, 0.17661946, 0.17435817, 0.17211354,
+	0.1698854, 0.16767362, 0.16547804, 0.16329853, 0.16113494,
+	0.15898713, 0.15685499, 0.15473837, 0.15263714, 0.15055119,
+	0.14848037, 0.14642459, 0.14438373, 0.14235765, 0.14034624,
+	0.13834943, 0.13636707, 0.13439907, 0.13244532, 0.13050574,
+	0.1285802, 0.12666863, 0.12477092, 0.12288698, 0.12101672,
+	0.119160056, 0.1173169, 0.115487166, 0.11367077, 0.11186763,
+	0.11007768, 0.10830083, 0.10653701, 0.10478614, 0.10304816,
+	0.101323, 0.09961058, 0.09791085, 0.09622374, 0.09454919,
+	0.09288713, 0.091237515, 0.08960028, 0.087975375, 0.08636274,
+	0.08476233, 0.083174095, 0.081597984, 0.08003395, 0.07848195,
+	0.076941945, 0.07541389, 0.07389775, 0.072393484, 0.07090106,
+	0.069420435, 0.06795159, 0.066494495, 0.06504912, 0.063615434,
+	0.062193416, 0.060783047, 0.059384305, 0.057997175,
+	0.05662164, 0.05525769, 0.053905312, 0.052564494, 0.051235236,
+	0.049917534, 0.048611384, 0.047316793, 0.046033762, 0.0447623,
+	0.043502413, 0.042254124, 0.041017443, 0.039792392,
+	0.038578995, 0.037377283, 0.036187284, 0.035009038,
+	0.033842582, 0.032687962, 0.031545233, 0.030414443, 0.02929566,
+	0.02818895, 0.027094385, 0.026012046, 0.024942026, 0.023884421,
+	0.022839336, 0.021806888, 0.020787204, 0.019780423, 0.0187867,
+	0.0178062, 0.016839107, 0.015885621, 0.014945968, 0.014020392,
+	0.013109165, 0.012212592, 0.011331013, 0.01046481, 0.009614414,
+	0.008780315, 0.007963077, 0.0071633533, 0.006381906,
+	0.0056196423, 0.0048776558, 0.004157295, 0.0034602648,
+	0.0027887989, 0.0021459677, 0.0015362998, 0.0009672693,
+	0.00045413437,
+}
diff --git a/contrib/go/_std_1.19/src/math/rand/normal.go b/contrib/go/_std_1.19/src/math/rand/normal.go
new file mode 100644
index 0000000000..6654479a00
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/rand/normal.go
@@ -0,0 +1,156 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package rand
+
+import (
+	"math"
+)
+
+/*
+ * Normal distribution
+ *
+ * See "The Ziggurat Method for Generating Random Variables"
+ * (Marsaglia & Tsang, 2000)
+ * http://www.jstatsoft.org/v05/i08/paper [pdf]
+ */
+
+const (
+	rn = 3.442619855899
+)
+
+func absInt32(i int32) uint32 {
+	if i < 0 {
+		return uint32(-i)
+	}
+	return uint32(i)
+}
+
+// NormFloat64 returns a normally distributed float64 in
+// the range -math.MaxFloat64 through +math.MaxFloat64 inclusive,
+// with standard normal distribution (mean = 0, stddev = 1).
+// To produce a different normal distribution, callers can
+// adjust the output using:
+//
+//	sample = NormFloat64() * desiredStdDev + desiredMean
+func (r *Rand) NormFloat64() float64 {
+	for {
+		j := int32(r.Uint32()) // Possibly negative
+		i := j & 0x7F
+		x := float64(j) * float64(wn[i])
+		if absInt32(j) < kn[i] {
+			// This case should be hit better than 99% of the time.
+			return x
+		}
+
+		if i == 0 {
+			// This extra work is only required for the base strip.
+			for {
+				x = -math.Log(r.Float64()) * (1.0 / rn)
+				y := -math.Log(r.Float64())
+				if y+y >= x*x {
+					break
+				}
+			}
+			if j > 0 {
+				return rn + x
+			}
+			return -rn - x
+		}
+		if fn[i]+float32(r.Float64())*(fn[i-1]-fn[i]) < float32(math.Exp(-.5*x*x)) {
+			return x
+		}
+	}
+}
+
+var kn = [128]uint32{
+	0x76ad2212, 0x0, 0x600f1b53, 0x6ce447a6, 0x725b46a2,
+	0x7560051d, 0x774921eb, 0x789a25bd, 0x799045c3, 0x7a4bce5d,
+	0x7adf629f, 0x7b5682a6, 0x7bb8a8c6, 0x7c0ae722, 0x7c50cce7,
+	0x7c8cec5b, 0x7cc12cd6, 0x7ceefed2, 0x7d177e0b, 0x7d3b8883,
+	0x7d5bce6c, 0x7d78dd64, 0x7d932886, 0x7dab0e57, 0x7dc0dd30,
+	0x7dd4d688, 0x7de73185, 0x7df81cea, 0x7e07c0a3, 0x7e163efa,
+	0x7e23b587, 0x7e303dfd, 0x7e3beec2, 0x7e46db77, 0x7e51155d,
+	0x7e5aabb3, 0x7e63abf7, 0x7e6c222c, 0x7e741906, 0x7e7b9a18,
+	0x7e82adfa, 0x7e895c63, 0x7e8fac4b, 0x7e95a3fb, 0x7e9b4924,
+	0x7ea0a0ef, 0x7ea5b00d, 0x7eaa7ac3, 0x7eaf04f3, 0x7eb3522a,
+	0x7eb765a5, 0x7ebb4259, 0x7ebeeafd, 0x7ec2620a, 0x7ec5a9c4,
+	0x7ec8c441, 0x7ecbb365, 0x7ece78ed, 0x7ed11671, 0x7ed38d62,
+	0x7ed5df12, 0x7ed80cb4, 0x7eda175c, 0x7edc0005, 0x7eddc78e,
+	0x7edf6ebf, 0x7ee0f647, 0x7ee25ebe, 0x7ee3a8a9, 0x7ee4d473,
+	0x7ee5e276, 0x7ee6d2f5, 0x7ee7a620, 0x7ee85c10, 0x7ee8f4cd,
+	0x7ee97047, 0x7ee9ce59, 0x7eea0eca, 0x7eea3147, 0x7eea3568,
+	0x7eea1aab, 0x7ee9e071, 0x7ee98602, 0x7ee90a88, 0x7ee86d08,
+	0x7ee7ac6a, 0x7ee6c769, 0x7ee5bc9c, 0x7ee48a67, 0x7ee32efc,
+	0x7ee1a857, 0x7edff42f, 0x7ede0ffa, 0x7edbf8d9, 0x7ed9ab94,
+	0x7ed7248d, 0x7ed45fae, 0x7ed1585c, 0x7ece095f, 0x7eca6ccb,
+	0x7ec67be2, 0x7ec22eee, 0x7ebd7d1a, 0x7eb85c35, 0x7eb2c075,
+	0x7eac9c20, 0x7ea5df27, 0x7e9e769f, 0x7e964c16, 0x7e8d44ba,
+	0x7e834033, 0x7e781728, 0x7e6b9933, 0x7e5d8a1a, 0x7e4d9ded,
+	0x7e3b737a, 0x7e268c2f, 0x7e0e3ff5, 0x7df1aa5d, 0x7dcf8c72,
+	0x7da61a1e, 0x7d72a0fb, 0x7d30e097, 0x7cd9b4ab, 0x7c600f1a,
+	0x7ba90bdc, 0x7a722176, 0x77d664e5,
+}
+var wn = [128]float32{
+	1.7290405e-09, 1.2680929e-10, 1.6897518e-10, 1.9862688e-10,
+	2.2232431e-10, 2.4244937e-10, 2.601613e-10, 2.7611988e-10,
+	2.9073963e-10, 3.042997e-10, 3.1699796e-10, 3.289802e-10,
+	3.4035738e-10, 3.5121603e-10, 3.616251e-10, 3.7164058e-10,
+	3.8130857e-10, 3.9066758e-10, 3.9975012e-10, 4.08584e-10,
+	4.1719309e-10, 4.2559822e-10, 4.338176e-10, 4.418672e-10,
+	4.497613e-10, 4.5751258e-10, 4.651324e-10, 4.7263105e-10,
+	4.8001775e-10, 4.87301e-10, 4.944885e-10, 5.015873e-10,
+	5.0860405e-10, 5.155446e-10, 5.2241467e-10, 5.2921934e-10,
+	5.359635e-10, 5.426517e-10, 5.4928817e-10, 5.5587696e-10,
+	5.624219e-10, 5.6892646e-10, 5.753941e-10, 5.818282e-10,
+	5.882317e-10, 5.946077e-10, 6.00959e-10, 6.072884e-10,
+	6.135985e-10, 6.19892e-10, 6.2617134e-10, 6.3243905e-10,
+	6.386974e-10, 6.449488e-10, 6.511956e-10, 6.5744005e-10,
+	6.6368433e-10, 6.699307e-10, 6.7618144e-10, 6.824387e-10,
+	6.8870465e-10, 6.949815e-10, 7.012715e-10, 7.075768e-10,
+	7.1389966e-10, 7.202424e-10, 7.266073e-10, 7.329966e-10,
+	7.394128e-10, 7.4585826e-10, 7.5233547e-10, 7.58847e-10,
+	7.653954e-10, 7.719835e-10, 7.7861395e-10, 7.852897e-10,
+	7.920138e-10, 7.987892e-10, 8.0561924e-10, 8.125073e-10,
+	8.194569e-10, 8.2647167e-10, 8.3355556e-10, 8.407127e-10,
+	8.479473e-10, 8.55264e-10, 8.6266755e-10, 8.7016316e-10,
+	8.777562e-10, 8.8545243e-10, 8.932582e-10, 9.0117996e-10,
+	9.09225e-10, 9.174008e-10, 9.2571584e-10, 9.341788e-10,
+	9.427997e-10, 9.515889e-10, 9.605579e-10, 9.697193e-10,
+	9.790869e-10, 9.88676e-10, 9.985036e-10, 1.0085882e-09,
+	1.0189509e-09, 1.0296151e-09, 1.0406069e-09, 1.0519566e-09,
+	1.063698e-09, 1.0758702e-09, 1.0885183e-09, 1.1016947e-09,
+	1.1154611e-09, 1.1298902e-09, 1.1450696e-09, 1.1611052e-09,
+	1.1781276e-09, 1.1962995e-09, 1.2158287e-09, 1.2369856e-09,
+	1.2601323e-09, 1.2857697e-09, 1.3146202e-09, 1.347784e-09,
+	1.3870636e-09, 1.4357403e-09, 1.5008659e-09, 1.6030948e-09,
+}
+var fn = [128]float32{
+	1, 0.9635997, 0.9362827, 0.9130436, 0.89228165, 0.87324303,
+	0.8555006, 0.8387836, 0.8229072, 0.8077383, 0.793177,
+	0.7791461, 0.7655842, 0.7524416, 0.73967725, 0.7272569,
+	0.7151515, 0.7033361, 0.69178915, 0.68049186, 0.6694277,
+	0.658582, 0.6479418, 0.63749546, 0.6272325, 0.6171434,
+	0.6072195, 0.5974532, 0.58783704, 0.5783647, 0.56903,
+	0.5598274, 0.5507518, 0.54179835, 0.5329627, 0.52424055,
+	0.5156282, 0.50712204, 0.49871865, 0.49041483, 0.48220766,
+	0.4740943, 0.46607214, 0.4581387, 0.45029163, 0.44252872,
+	0.43484783, 0.427247, 0.41972435, 0.41227803, 0.40490642,
+	0.39760786, 0.3903808, 0.3832238, 0.37613547, 0.36911446,
+	0.3621595, 0.35526937, 0.34844297, 0.34167916, 0.33497685,
+	0.3283351, 0.3217529, 0.3152294, 0.30876362, 0.30235484,
+	0.29600215, 0.28970486, 0.2834622, 0.2772735, 0.27113807,
+	0.2650553, 0.25902456, 0.2530453, 0.24711695, 0.241239,
+	0.23541094, 0.22963232, 0.2239027, 0.21822165, 0.21258877,
+	0.20700371, 0.20146611, 0.19597565, 0.19053204, 0.18513499,
+	0.17978427, 0.17447963, 0.1692209, 0.16400786, 0.15884037,
+	0.15371831, 0.14864157, 0.14361008, 0.13862377, 0.13368265,
+	0.12878671, 0.12393598, 0.119130544, 0.11437051, 0.10965602,
+	0.104987256, 0.10036444, 0.095787846, 0.0912578, 0.08677467,
+	0.0823389, 0.077950984, 0.073611505, 0.06932112, 0.06508058,
+	0.06089077, 0.056752663, 0.0526674, 0.048636295, 0.044660863,
+	0.040742867, 0.03688439, 0.033087887, 0.029356318,
+	0.025693292, 0.022103304, 0.018592102, 0.015167298,
+	0.011839478, 0.008624485, 0.005548995, 0.0026696292,
+}
diff --git a/contrib/go/_std_1.19/src/math/rand/rand.go b/contrib/go/_std_1.19/src/math/rand/rand.go
new file mode 100644
index 0000000000..4cce3dab64
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/rand/rand.go
@@ -0,0 +1,419 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package rand implements pseudo-random number generators unsuitable for
+// security-sensitive work.
+//
+// Random numbers are generated by a Source. Top-level functions, such as
+// Float64 and Int, use a default shared Source that produces a deterministic
+// sequence of values each time a program is run. Use the Seed function to
+// initialize the default Source if different behavior is required for each run.
+// The default Source is safe for concurrent use by multiple goroutines, but
+// Sources created by NewSource are not.
+//
+// This package's outputs might be easily predictable regardless of how it's
+// seeded. For random numbers suitable for security-sensitive work, see the
+// crypto/rand package.
+package rand
+
+import "sync"
+
+// A Source represents a source of uniformly-distributed
+// pseudo-random int64 values in the range [0, 1<<63).
+type Source interface {
+	Int63() int64
+	Seed(seed int64)
+}
+
+// A Source64 is a Source that can also generate
+// uniformly-distributed pseudo-random uint64 values in
+// the range [0, 1<<64) directly.
+// If a Rand r's underlying Source s implements Source64,
+// then r.Uint64 returns the result of one call to s.Uint64
+// instead of making two calls to s.Int63.
+type Source64 interface {
+	Source
+	Uint64() uint64
+}
+
+// NewSource returns a new pseudo-random Source seeded with the given value.
+// Unlike the default Source used by top-level functions, this source is not
+// safe for concurrent use by multiple goroutines.
+func NewSource(seed int64) Source {
+	var rng rngSource
+	rng.Seed(seed)
+	return &rng
+}
+
+// A Rand is a source of random numbers.
+type Rand struct {
+	src Source
+	s64 Source64 // non-nil if src is source64
+
+	// readVal contains remainder of 63-bit integer used for bytes
+	// generation during most recent Read call.
+	// It is saved so next Read call can start where the previous
+	// one finished.
+	readVal int64
+	// readPos indicates the number of low-order bytes of readVal
+	// that are still valid.
+	readPos int8
+}
+
+// New returns a new Rand that uses random values from src
+// to generate other random values.
+func New(src Source) *Rand {
+	s64, _ := src.(Source64)
+	return &Rand{src: src, s64: s64}
+}
+
+// Seed uses the provided seed value to initialize the generator to a deterministic state.
+// Seed should not be called concurrently with any other Rand method.
+func (r *Rand) Seed(seed int64) {
+	if lk, ok := r.src.(*lockedSource); ok {
+		lk.seedPos(seed, &r.readPos)
+		return
+	}
+
+	r.src.Seed(seed)
+	r.readPos = 0
+}
+
+// Int63 returns a non-negative pseudo-random 63-bit integer as an int64.
+func (r *Rand) Int63() int64 { return r.src.Int63() }
+
+// Uint32 returns a pseudo-random 32-bit value as a uint32.
+func (r *Rand) Uint32() uint32 { return uint32(r.Int63() >> 31) }
+
+// Uint64 returns a pseudo-random 64-bit value as a uint64.
+func (r *Rand) Uint64() uint64 {
+	if r.s64 != nil {
+		return r.s64.Uint64()
+	}
+	return uint64(r.Int63())>>31 | uint64(r.Int63())<<32
+}
+
+// Int31 returns a non-negative pseudo-random 31-bit integer as an int32.
+func (r *Rand) Int31() int32 { return int32(r.Int63() >> 32) }
+
+// Int returns a non-negative pseudo-random int.
+func (r *Rand) Int() int {
+	u := uint(r.Int63())
+	return int(u << 1 >> 1) // clear sign bit if int == int32
+}
+
+// Int63n returns, as an int64, a non-negative pseudo-random number in the half-open interval [0,n).
+// It panics if n <= 0.
+func (r *Rand) Int63n(n int64) int64 {
+	if n <= 0 {
+		panic("invalid argument to Int63n")
+	}
+	if n&(n-1) == 0 { // n is power of two, can mask
+		return r.Int63() & (n - 1)
+	}
+	max := int64((1 << 63) - 1 - (1<<63)%uint64(n))
+	v := r.Int63()
+	for v > max {
+		v = r.Int63()
+	}
+	return v % n
+}
+
+// Int31n returns, as an int32, a non-negative pseudo-random number in the half-open interval [0,n).
+// It panics if n <= 0.
+func (r *Rand) Int31n(n int32) int32 {
+	if n <= 0 {
+		panic("invalid argument to Int31n")
+	}
+	if n&(n-1) == 0 { // n is power of two, can mask
+		return r.Int31() & (n - 1)
+	}
+	max := int32((1 << 31) - 1 - (1<<31)%uint32(n))
+	v := r.Int31()
+	for v > max {
+		v = r.Int31()
+	}
+	return v % n
+}
+
+// int31n returns, as an int32, a non-negative pseudo-random number in the half-open interval [0,n).
+// n must be > 0, but int31n does not check this; the caller must ensure it.
+// int31n exists because Int31n is inefficient, but Go 1 compatibility
+// requires that the stream of values produced by math/rand remain unchanged.
+// int31n can thus only be used internally, by newly introduced APIs.
+//
+// For implementation details, see:
+// https://lemire.me/blog/2016/06/27/a-fast-alternative-to-the-modulo-reduction
+// https://lemire.me/blog/2016/06/30/fast-random-shuffling
+func (r *Rand) int31n(n int32) int32 {
+	v := r.Uint32()
+	prod := uint64(v) * uint64(n)
+	low := uint32(prod)
+	if low < uint32(n) {
+		thresh := uint32(-n) % uint32(n)
+		for low < thresh {
+			v = r.Uint32()
+			prod = uint64(v) * uint64(n)
+			low = uint32(prod)
+		}
+	}
+	return int32(prod >> 32)
+}
+
+// Intn returns, as an int, a non-negative pseudo-random number in the half-open interval [0,n).
+// It panics if n <= 0.
+func (r *Rand) Intn(n int) int {
+	if n <= 0 {
+		panic("invalid argument to Intn")
+	}
+	if n <= 1<<31-1 {
+		return int(r.Int31n(int32(n)))
+	}
+	return int(r.Int63n(int64(n)))
+}
+
+// Float64 returns, as a float64, a pseudo-random number in the half-open interval [0.0,1.0).
+func (r *Rand) Float64() float64 {
+	// A clearer, simpler implementation would be:
+	//	return float64(r.Int63n(1<<53)) / (1<<53)
+	// However, Go 1 shipped with
+	//	return float64(r.Int63()) / (1 << 63)
+	// and we want to preserve that value stream.
+	//
+	// There is one bug in the value stream: r.Int63() may be so close
+	// to 1<<63 that the division rounds up to 1.0, and we've guaranteed
+	// that the result is always less than 1.0.
+	//
+	// We tried to fix this by mapping 1.0 back to 0.0, but since float64
+	// values near 0 are much denser than near 1, mapping 1 to 0 caused
+	// a theoretically significant overshoot in the probability of returning 0.
+	// Instead of that, if we round up to 1, just try again.
+	// Getting 1 only happens 1/2⁵³ of the time, so most clients
+	// will not observe it anyway.
+again:
+	f := float64(r.Int63()) / (1 << 63)
+	if f == 1 {
+		goto again // resample; this branch is taken O(never)
+	}
+	return f
+}
+
+// Float32 returns, as a float32, a pseudo-random number in the half-open interval [0.0,1.0).
+func (r *Rand) Float32() float32 {
+	// Same rationale as in Float64: we want to preserve the Go 1 value
+	// stream except we want to fix it not to return 1.0
+	// This only happens 1/2²⁴ of the time (plus the 1/2⁵³ of the time in Float64).
+again:
+	f := float32(r.Float64())
+	if f == 1 {
+		goto again // resample; this branch is taken O(very rarely)
+	}
+	return f
+}
+
+// Perm returns, as a slice of n ints, a pseudo-random permutation of the integers
+// in the half-open interval [0,n).
+func (r *Rand) Perm(n int) []int {
+	m := make([]int, n)
+	// In the following loop, the iteration when i=0 always swaps m[0] with m[0].
+	// A change to remove this useless iteration is to assign 1 to i in the init
+	// statement. But Perm also effects r. Making this change will affect
+	// the final state of r. So this change can't be made for compatibility
+	// reasons for Go 1.
+	for i := 0; i < n; i++ {
+		j := r.Intn(i + 1)
+		m[i] = m[j]
+		m[j] = i
+	}
+	return m
+}
+
+// Shuffle pseudo-randomizes the order of elements.
+// n is the number of elements. Shuffle panics if n < 0.
+// swap swaps the elements with indexes i and j.
+func (r *Rand) Shuffle(n int, swap func(i, j int)) {
+	if n < 0 {
+		panic("invalid argument to Shuffle")
+	}
+
+	// Fisher-Yates shuffle: https://en.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle
+	// Shuffle really ought not be called with n that doesn't fit in 32 bits.
+	// Not only will it take a very long time, but with 2³¹! possible permutations,
+	// there's no way that any PRNG can have a big enough internal state to
+	// generate even a minuscule percentage of the possible permutations.
+	// Nevertheless, the right API signature accepts an int n, so handle it as best we can.
+	i := n - 1
+	for ; i > 1<<31-1-1; i-- {
+		j := int(r.Int63n(int64(i + 1)))
+		swap(i, j)
+	}
+	for ; i > 0; i-- {
+		j := int(r.int31n(int32(i + 1)))
+		swap(i, j)
+	}
+}
+
+// Read generates len(p) random bytes and writes them into p. It
+// always returns len(p) and a nil error.
+// Read should not be called concurrently with any other Rand method.
+func (r *Rand) Read(p []byte) (n int, err error) {
+	if lk, ok := r.src.(*lockedSource); ok {
+		return lk.read(p, &r.readVal, &r.readPos)
+	}
+	return read(p, r.src, &r.readVal, &r.readPos)
+}
+
+func read(p []byte, src Source, readVal *int64, readPos *int8) (n int, err error) {
+	pos := *readPos
+	val := *readVal
+	rng, _ := src.(*rngSource)
+	for n = 0; n < len(p); n++ {
+		if pos == 0 {
+			if rng != nil {
+				val = rng.Int63()
+			} else {
+				val = src.Int63()
+			}
+			pos = 7
+		}
+		p[n] = byte(val)
+		val >>= 8
+		pos--
+	}
+	*readPos = pos
+	*readVal = val
+	return
+}
+
+/*
+ * Top-level convenience functions
+ */
+
+var globalRand = New(&lockedSource{src: NewSource(1).(*rngSource)})
+
+// Type assert that globalRand's source is a lockedSource whose src is a *rngSource.
+var _ *rngSource = globalRand.src.(*lockedSource).src
+
+// Seed uses the provided seed value to initialize the default Source to a
+// deterministic state. If Seed is not called, the generator behaves as
+// if seeded by Seed(1). Seed values that have the same remainder when
+// divided by 2³¹-1 generate the same pseudo-random sequence.
+// Seed, unlike the Rand.Seed method, is safe for concurrent use.
+func Seed(seed int64) { globalRand.Seed(seed) }
+
+// Int63 returns a non-negative pseudo-random 63-bit integer as an int64
+// from the default Source.
+func Int63() int64 { return globalRand.Int63() }
+
+// Uint32 returns a pseudo-random 32-bit value as a uint32
+// from the default Source.
+func Uint32() uint32 { return globalRand.Uint32() }
+
+// Uint64 returns a pseudo-random 64-bit value as a uint64
+// from the default Source.
+func Uint64() uint64 { return globalRand.Uint64() }
+
+// Int31 returns a non-negative pseudo-random 31-bit integer as an int32
+// from the default Source.
+func Int31() int32 { return globalRand.Int31() }
+
+// Int returns a non-negative pseudo-random int from the default Source.
+func Int() int { return globalRand.Int() }
+
+// Int63n returns, as an int64, a non-negative pseudo-random number in the half-open interval [0,n)
+// from the default Source.
+// It panics if n <= 0.
+func Int63n(n int64) int64 { return globalRand.Int63n(n) }
+
+// Int31n returns, as an int32, a non-negative pseudo-random number in the half-open interval [0,n)
+// from the default Source.
+// It panics if n <= 0.
+func Int31n(n int32) int32 { return globalRand.Int31n(n) }
+
+// Intn returns, as an int, a non-negative pseudo-random number in the half-open interval [0,n)
+// from the default Source.
+// It panics if n <= 0.
+func Intn(n int) int { return globalRand.Intn(n) }
+
+// Float64 returns, as a float64, a pseudo-random number in the half-open interval [0.0,1.0)
+// from the default Source.
+func Float64() float64 { return globalRand.Float64() }
+
+// Float32 returns, as a float32, a pseudo-random number in the half-open interval [0.0,1.0)
+// from the default Source.
+func Float32() float32 { return globalRand.Float32() }
+
+// Perm returns, as a slice of n ints, a pseudo-random permutation of the integers
+// in the half-open interval [0,n) from the default Source.
+func Perm(n int) []int { return globalRand.Perm(n) }
+
+// Shuffle pseudo-randomizes the order of elements using the default Source.
+// n is the number of elements. Shuffle panics if n < 0.
+// swap swaps the elements with indexes i and j.
+func Shuffle(n int, swap func(i, j int)) { globalRand.Shuffle(n, swap) }
+
+// Read generates len(p) random bytes from the default Source and
+// writes them into p. It always returns len(p) and a nil error.
+// Read, unlike the Rand.Read method, is safe for concurrent use.
+func Read(p []byte) (n int, err error) { return globalRand.Read(p) }
+
+// NormFloat64 returns a normally distributed float64 in the range
+// [-math.MaxFloat64, +math.MaxFloat64] with
+// standard normal distribution (mean = 0, stddev = 1)
+// from the default Source.
+// To produce a different normal distribution, callers can
+// adjust the output using:
+//
+//	sample = NormFloat64() * desiredStdDev + desiredMean
+func NormFloat64() float64 { return globalRand.NormFloat64() }
+
+// ExpFloat64 returns an exponentially distributed float64 in the range
+// (0, +math.MaxFloat64] with an exponential distribution whose rate parameter
+// (lambda) is 1 and whose mean is 1/lambda (1) from the default Source.
+// To produce a distribution with a different rate parameter,
+// callers can adjust the output using:
+//
+//	sample = ExpFloat64() / desiredRateParameter
+func ExpFloat64() float64 { return globalRand.ExpFloat64() }
+
+type lockedSource struct {
+	lk  sync.Mutex
+	src *rngSource
+}
+
+func (r *lockedSource) Int63() (n int64) {
+	r.lk.Lock()
+	n = r.src.Int63()
+	r.lk.Unlock()
+	return
+}
+
+func (r *lockedSource) Uint64() (n uint64) {
+	r.lk.Lock()
+	n = r.src.Uint64()
+	r.lk.Unlock()
+	return
+}
+
+func (r *lockedSource) Seed(seed int64) {
+	r.lk.Lock()
+	r.src.Seed(seed)
+	r.lk.Unlock()
+}
+
+// seedPos implements Seed for a lockedSource without a race condition.
+func (r *lockedSource) seedPos(seed int64, readPos *int8) {
+	r.lk.Lock()
+	r.src.Seed(seed)
+	*readPos = 0
+	r.lk.Unlock()
+}
+
+// read implements Read for a lockedSource without a race condition.
+func (r *lockedSource) read(p []byte, readVal *int64, readPos *int8) (n int, err error) {
+	r.lk.Lock()
+	n, err = read(p, r.src, readVal, readPos)
+	r.lk.Unlock()
+	return
+}
diff --git a/contrib/go/_std_1.18/src/math/rand/rng.go b/contrib/go/_std_1.19/src/math/rand/rng.go
index f305df1a20..f305df1a20 100644
--- a/contrib/go/_std_1.18/src/math/rand/rng.go
+++ b/contrib/go/_std_1.19/src/math/rand/rng.go
diff --git a/contrib/go/_std_1.18/src/math/rand/zipf.go b/contrib/go/_std_1.19/src/math/rand/zipf.go
index f04c814eb7..f04c814eb7 100644
--- a/contrib/go/_std_1.18/src/math/rand/zipf.go
+++ b/contrib/go/_std_1.19/src/math/rand/zipf.go
diff --git a/contrib/go/_std_1.19/src/math/remainder.go b/contrib/go/_std_1.19/src/math/remainder.go
new file mode 100644
index 0000000000..8e99345c59
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/remainder.go
@@ -0,0 +1,95 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// The original C code and the comment below are from
+// FreeBSD's /usr/src/lib/msun/src/e_remainder.c and came
+// with this notice. The go code is a simplified version of
+// the original C.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+// __ieee754_remainder(x,y)
+// Return :
+//      returns  x REM y  =  x - [x/y]*y  as if in infinite
+//      precision arithmetic, where [x/y] is the (infinite bit)
+//      integer nearest x/y (in half way cases, choose the even one).
+// Method :
+//      Based on Mod() returning  x - [x/y]chopped * y  exactly.
+
+// Remainder returns the IEEE 754 floating-point remainder of x/y.
+//
+// Special cases are:
+//
+//	Remainder(±Inf, y) = NaN
+//	Remainder(NaN, y) = NaN
+//	Remainder(x, 0) = NaN
+//	Remainder(x, ±Inf) = x
+//	Remainder(x, NaN) = NaN
+func Remainder(x, y float64) float64 {
+	if haveArchRemainder {
+		return archRemainder(x, y)
+	}
+	return remainder(x, y)
+}
+
+func remainder(x, y float64) float64 {
+	const (
+		Tiny    = 4.45014771701440276618e-308 // 0x0020000000000000
+		HalfMax = MaxFloat64 / 2
+	)
+	// special cases
+	switch {
+	case IsNaN(x) || IsNaN(y) || IsInf(x, 0) || y == 0:
+		return NaN()
+	case IsInf(y, 0):
+		return x
+	}
+	sign := false
+	if x < 0 {
+		x = -x
+		sign = true
+	}
+	if y < 0 {
+		y = -y
+	}
+	if x == y {
+		if sign {
+			zero := 0.0
+			return -zero
+		}
+		return 0
+	}
+	if y <= HalfMax {
+		x = Mod(x, y+y) // now x < 2y
+	}
+	if y < Tiny {
+		if x+x > y {
+			x -= y
+			if x+x >= y {
+				x -= y
+			}
+		}
+	} else {
+		yHalf := 0.5 * y
+		if x > yHalf {
+			x -= y
+			if x >= yHalf {
+				x -= y
+			}
+		}
+	}
+	if sign {
+		x = -x
+	}
+	return x
+}
diff --git a/contrib/go/_std_1.18/src/math/signbit.go b/contrib/go/_std_1.19/src/math/signbit.go
index f6e61d660e..f6e61d660e 100644
--- a/contrib/go/_std_1.18/src/math/signbit.go
+++ b/contrib/go/_std_1.19/src/math/signbit.go
diff --git a/contrib/go/_std_1.19/src/math/sin.go b/contrib/go/_std_1.19/src/math/sin.go
new file mode 100644
index 0000000000..4793d7e7cd
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/sin.go
@@ -0,0 +1,244 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+	Floating-point sine and cosine.
+*/
+
+// The original C code, the long comment, and the constants
+// below were from http://netlib.sandia.gov/cephes/cmath/sin.c,
+// available from http://www.netlib.org/cephes/cmath.tgz.
+// The go code is a simplified version of the original C.
+//
+//      sin.c
+//
+//      Circular sine
+//
+// SYNOPSIS:
+//
+// double x, y, sin();
+// y = sin( x );
+//
+// DESCRIPTION:
+//
+// Range reduction is into intervals of pi/4.  The reduction error is nearly
+// eliminated by contriving an extended precision modular arithmetic.
+//
+// Two polynomial approximating functions are employed.
+// Between 0 and pi/4 the sine is approximated by
+//      x  +  x**3 P(x**2).
+// Between pi/4 and pi/2 the cosine is represented as
+//      1  -  x**2 Q(x**2).
+//
+// ACCURACY:
+//
+//                      Relative error:
+// arithmetic   domain      # trials      peak         rms
+//    DEC       0, 10       150000       3.0e-17     7.8e-18
+//    IEEE -1.07e9,+1.07e9  130000       2.1e-16     5.4e-17
+//
+// Partial loss of accuracy begins to occur at x = 2**30 = 1.074e9.  The loss
+// is not gradual, but jumps suddenly to about 1 part in 10e7.  Results may
+// be meaningless for x > 2**49 = 5.6e14.
+//
+//      cos.c
+//
+//      Circular cosine
+//
+// SYNOPSIS:
+//
+// double x, y, cos();
+// y = cos( x );
+//
+// DESCRIPTION:
+//
+// Range reduction is into intervals of pi/4.  The reduction error is nearly
+// eliminated by contriving an extended precision modular arithmetic.
+//
+// Two polynomial approximating functions are employed.
+// Between 0 and pi/4 the cosine is approximated by
+//      1  -  x**2 Q(x**2).
+// Between pi/4 and pi/2 the sine is represented as
+//      x  +  x**3 P(x**2).
+//
+// ACCURACY:
+//
+//                      Relative error:
+// arithmetic   domain      # trials      peak         rms
+//    IEEE -1.07e9,+1.07e9  130000       2.1e-16     5.4e-17
+//    DEC        0,+1.07e9   17000       3.0e-17     7.2e-18
+//
+// Cephes Math Library Release 2.8:  June, 2000
+// Copyright 1984, 1987, 1989, 1992, 2000 by Stephen L. Moshier
+//
+// The readme file at http://netlib.sandia.gov/cephes/ says:
+//    Some software in this archive may be from the book _Methods and
+// Programs for Mathematical Functions_ (Prentice-Hall or Simon & Schuster
+// International, 1989) or from the Cephes Mathematical Library, a
+// commercial product. In either event, it is copyrighted by the author.
+// What you see here may be used freely but it comes with no support or
+// guarantee.
+//
+//   The two known misprints in the book are repaired here in the
+// source listings for the gamma function and the incomplete beta
+// integral.
+//
+//   Stephen L. Moshier
+//   moshier@na-net.ornl.gov
+
+// sin coefficients
+var _sin = [...]float64{
+	1.58962301576546568060e-10, // 0x3de5d8fd1fd19ccd
+	-2.50507477628578072866e-8, // 0xbe5ae5e5a9291f5d
+	2.75573136213857245213e-6,  // 0x3ec71de3567d48a1
+	-1.98412698295895385996e-4, // 0xbf2a01a019bfdf03
+	8.33333333332211858878e-3,  // 0x3f8111111110f7d0
+	-1.66666666666666307295e-1, // 0xbfc5555555555548
+}
+
+// cos coefficients
+var _cos = [...]float64{
+	-1.13585365213876817300e-11, // 0xbda8fa49a0861a9b
+	2.08757008419747316778e-9,   // 0x3e21ee9d7b4e3f05
+	-2.75573141792967388112e-7,  // 0xbe927e4f7eac4bc6
+	2.48015872888517045348e-5,   // 0x3efa01a019c844f5
+	-1.38888888888730564116e-3,  // 0xbf56c16c16c14f91
+	4.16666666666665929218e-2,   // 0x3fa555555555554b
+}
+
+// Cos returns the cosine of the radian argument x.
+//
+// Special cases are:
+//
+//	Cos(±Inf) = NaN
+//	Cos(NaN) = NaN
+func Cos(x float64) float64 {
+	if haveArchCos {
+		return archCos(x)
+	}
+	return cos(x)
+}
+
+func cos(x float64) float64 {
+	const (
+		PI4A = 7.85398125648498535156e-1  // 0x3fe921fb40000000, Pi/4 split into three parts
+		PI4B = 3.77489470793079817668e-8  // 0x3e64442d00000000,
+		PI4C = 2.69515142907905952645e-15 // 0x3ce8469898cc5170,
+	)
+	// special cases
+	switch {
+	case IsNaN(x) || IsInf(x, 0):
+		return NaN()
+	}
+
+	// make argument positive
+	sign := false
+	x = Abs(x)
+
+	var j uint64
+	var y, z float64
+	if x >= reduceThreshold {
+		j, z = trigReduce(x)
+	} else {
+		j = uint64(x * (4 / Pi)) // integer part of x/(Pi/4), as integer for tests on the phase angle
+		y = float64(j)           // integer part of x/(Pi/4), as float
+
+		// map zeros to origin
+		if j&1 == 1 {
+			j++
+			y++
+		}
+		j &= 7                               // octant modulo 2Pi radians (360 degrees)
+		z = ((x - y*PI4A) - y*PI4B) - y*PI4C // Extended precision modular arithmetic
+	}
+
+	if j > 3 {
+		j -= 4
+		sign = !sign
+	}
+	if j > 1 {
+		sign = !sign
+	}
+
+	zz := z * z
+	if j == 1 || j == 2 {
+		y = z + z*zz*((((((_sin[0]*zz)+_sin[1])*zz+_sin[2])*zz+_sin[3])*zz+_sin[4])*zz+_sin[5])
+	} else {
+		y = 1.0 - 0.5*zz + zz*zz*((((((_cos[0]*zz)+_cos[1])*zz+_cos[2])*zz+_cos[3])*zz+_cos[4])*zz+_cos[5])
+	}
+	if sign {
+		y = -y
+	}
+	return y
+}
+
+// Sin returns the sine of the radian argument x.
+//
+// Special cases are:
+//
+//	Sin(±0) = ±0
+//	Sin(±Inf) = NaN
+//	Sin(NaN) = NaN
+func Sin(x float64) float64 {
+	if haveArchSin {
+		return archSin(x)
+	}
+	return sin(x)
+}
+
+func sin(x float64) float64 {
+	const (
+		PI4A = 7.85398125648498535156e-1  // 0x3fe921fb40000000, Pi/4 split into three parts
+		PI4B = 3.77489470793079817668e-8  // 0x3e64442d00000000,
+		PI4C = 2.69515142907905952645e-15 // 0x3ce8469898cc5170,
+	)
+	// special cases
+	switch {
+	case x == 0 || IsNaN(x):
+		return x // return ±0 || NaN()
+	case IsInf(x, 0):
+		return NaN()
+	}
+
+	// make argument positive but save the sign
+	sign := false
+	if x < 0 {
+		x = -x
+		sign = true
+	}
+
+	var j uint64
+	var y, z float64
+	if x >= reduceThreshold {
+		j, z = trigReduce(x)
+	} else {
+		j = uint64(x * (4 / Pi)) // integer part of x/(Pi/4), as integer for tests on the phase angle
+		y = float64(j)           // integer part of x/(Pi/4), as float
+
+		// map zeros to origin
+		if j&1 == 1 {
+			j++
+			y++
+		}
+		j &= 7                               // octant modulo 2Pi radians (360 degrees)
+		z = ((x - y*PI4A) - y*PI4B) - y*PI4C // Extended precision modular arithmetic
+	}
+	// reflect in x axis
+	if j > 3 {
+		sign = !sign
+		j -= 4
+	}
+	zz := z * z
+	if j == 1 || j == 2 {
+		y = 1.0 - 0.5*zz + zz*zz*((((((_cos[0]*zz)+_cos[1])*zz+_cos[2])*zz+_cos[3])*zz+_cos[4])*zz+_cos[5])
+	} else {
+		y = z + z*zz*((((((_sin[0]*zz)+_sin[1])*zz+_sin[2])*zz+_sin[3])*zz+_sin[4])*zz+_sin[5])
+	}
+	if sign {
+		y = -y
+	}
+	return y
+}
diff --git a/contrib/go/_std_1.19/src/math/sincos.go b/contrib/go/_std_1.19/src/math/sincos.go
new file mode 100644
index 0000000000..e3fb96094f
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/sincos.go
@@ -0,0 +1,73 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Coefficients _sin[] and _cos[] are found in pkg/math/sin.go.
+
+// Sincos returns Sin(x), Cos(x).
+//
+// Special cases are:
+//
+//	Sincos(±0) = ±0, 1
+//	Sincos(±Inf) = NaN, NaN
+//	Sincos(NaN) = NaN, NaN
+func Sincos(x float64) (sin, cos float64) {
+	const (
+		PI4A = 7.85398125648498535156e-1  // 0x3fe921fb40000000, Pi/4 split into three parts
+		PI4B = 3.77489470793079817668e-8  // 0x3e64442d00000000,
+		PI4C = 2.69515142907905952645e-15 // 0x3ce8469898cc5170,
+	)
+	// special cases
+	switch {
+	case x == 0:
+		return x, 1 // return ±0.0, 1.0
+	case IsNaN(x) || IsInf(x, 0):
+		return NaN(), NaN()
+	}
+
+	// make argument positive
+	sinSign, cosSign := false, false
+	if x < 0 {
+		x = -x
+		sinSign = true
+	}
+
+	var j uint64
+	var y, z float64
+	if x >= reduceThreshold {
+		j, z = trigReduce(x)
+	} else {
+		j = uint64(x * (4 / Pi)) // integer part of x/(Pi/4), as integer for tests on the phase angle
+		y = float64(j)           // integer part of x/(Pi/4), as float
+
+		if j&1 == 1 { // map zeros to origin
+			j++
+			y++
+		}
+		j &= 7                               // octant modulo 2Pi radians (360 degrees)
+		z = ((x - y*PI4A) - y*PI4B) - y*PI4C // Extended precision modular arithmetic
+	}
+	if j > 3 { // reflect in x axis
+		j -= 4
+		sinSign, cosSign = !sinSign, !cosSign
+	}
+	if j > 1 {
+		cosSign = !cosSign
+	}
+
+	zz := z * z
+	cos = 1.0 - 0.5*zz + zz*zz*((((((_cos[0]*zz)+_cos[1])*zz+_cos[2])*zz+_cos[3])*zz+_cos[4])*zz+_cos[5])
+	sin = z + z*zz*((((((_sin[0]*zz)+_sin[1])*zz+_sin[2])*zz+_sin[3])*zz+_sin[4])*zz+_sin[5])
+	if j == 1 || j == 2 {
+		sin, cos = cos, sin
+	}
+	if cosSign {
+		cos = -cos
+	}
+	if sinSign {
+		sin = -sin
+	}
+	return
+}
diff --git a/contrib/go/_std_1.19/src/math/sinh.go b/contrib/go/_std_1.19/src/math/sinh.go
new file mode 100644
index 0000000000..78b3c299d6
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/sinh.go
@@ -0,0 +1,93 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+	Floating-point hyperbolic sine and cosine.
+
+	The exponential func is called for arguments
+	greater in magnitude than 0.5.
+
+	A series is used for arguments smaller in magnitude than 0.5.
+
+	Cosh(x) is computed from the exponential func for
+	all arguments.
+*/
+
+// Sinh returns the hyperbolic sine of x.
+//
+// Special cases are:
+//
+//	Sinh(±0) = ±0
+//	Sinh(±Inf) = ±Inf
+//	Sinh(NaN) = NaN
+func Sinh(x float64) float64 {
+	if haveArchSinh {
+		return archSinh(x)
+	}
+	return sinh(x)
+}
+
+func sinh(x float64) float64 {
+	// The coefficients are #2029 from Hart & Cheney. (20.36D)
+	const (
+		P0 = -0.6307673640497716991184787251e+6
+		P1 = -0.8991272022039509355398013511e+5
+		P2 = -0.2894211355989563807284660366e+4
+		P3 = -0.2630563213397497062819489e+2
+		Q0 = -0.6307673640497716991212077277e+6
+		Q1 = 0.1521517378790019070696485176e+5
+		Q2 = -0.173678953558233699533450911e+3
+	)
+
+	sign := false
+	if x < 0 {
+		x = -x
+		sign = true
+	}
+
+	var temp float64
+	switch {
+	case x > 21:
+		temp = Exp(x) * 0.5
+
+	case x > 0.5:
+		ex := Exp(x)
+		temp = (ex - 1/ex) * 0.5
+
+	default:
+		sq := x * x
+		temp = (((P3*sq+P2)*sq+P1)*sq + P0) * x
+		temp = temp / (((sq+Q2)*sq+Q1)*sq + Q0)
+	}
+
+	if sign {
+		temp = -temp
+	}
+	return temp
+}
+
+// Cosh returns the hyperbolic cosine of x.
+//
+// Special cases are:
+//
+//	Cosh(±0) = 1
+//	Cosh(±Inf) = +Inf
+//	Cosh(NaN) = NaN
+func Cosh(x float64) float64 {
+	if haveArchCosh {
+		return archCosh(x)
+	}
+	return cosh(x)
+}
+
+func cosh(x float64) float64 {
+	x = Abs(x)
+	if x > 21 {
+		return Exp(x) * 0.5
+	}
+	ex := Exp(x)
+	return (ex + 1/ex) * 0.5
+}
diff --git a/contrib/go/_std_1.19/src/math/sqrt.go b/contrib/go/_std_1.19/src/math/sqrt.go
new file mode 100644
index 0000000000..b6d80c2c6f
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/sqrt.go
@@ -0,0 +1,150 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// The original C code and the long comment below are
+// from FreeBSD's /usr/src/lib/msun/src/e_sqrt.c and
+// came with this notice. The go code is a simplified
+// version of the original C.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+// __ieee754_sqrt(x)
+// Return correctly rounded sqrt.
+//           -----------------------------------------
+//           | Use the hardware sqrt if you have one |
+//           -----------------------------------------
+// Method:
+//   Bit by bit method using integer arithmetic. (Slow, but portable)
+//   1. Normalization
+//      Scale x to y in [1,4) with even powers of 2:
+//      find an integer k such that  1 <= (y=x*2**(2k)) < 4, then
+//              sqrt(x) = 2**k * sqrt(y)
+//   2. Bit by bit computation
+//      Let q  = sqrt(y) truncated to i bit after binary point (q = 1),
+//           i                                                   0
+//                                     i+1         2
+//          s  = 2*q , and      y  =  2   * ( y - q  ).          (1)
+//           i      i            i                 i
+//
+//      To compute q    from q , one checks whether
+//                  i+1       i
+//
+//                            -(i+1) 2
+//                      (q + 2      )  <= y.                     (2)
+//                        i
+//                                                            -(i+1)
+//      If (2) is false, then q   = q ; otherwise q   = q  + 2      .
+//                             i+1   i             i+1   i
+//
+//      With some algebraic manipulation, it is not difficult to see
+//      that (2) is equivalent to
+//                             -(i+1)
+//                      s  +  2       <= y                       (3)
+//                       i                i
+//
+//      The advantage of (3) is that s  and y  can be computed by
+//                                    i      i
+//      the following recurrence formula:
+//          if (3) is false
+//
+//          s     =  s  ,       y    = y   ;                     (4)
+//           i+1      i          i+1    i
+//
+//      otherwise,
+//                         -i                      -(i+1)
+//          s     =  s  + 2  ,  y    = y  -  s  - 2              (5)
+//           i+1      i          i+1    i     i
+//
+//      One may easily use induction to prove (4) and (5).
+//      Note. Since the left hand side of (3) contain only i+2 bits,
+//            it is not necessary to do a full (53-bit) comparison
+//            in (3).
+//   3. Final rounding
+//      After generating the 53 bits result, we compute one more bit.
+//      Together with the remainder, we can decide whether the
+//      result is exact, bigger than 1/2ulp, or less than 1/2ulp
+//      (it will never equal to 1/2ulp).
+//      The rounding mode can be detected by checking whether
+//      huge + tiny is equal to huge, and whether huge - tiny is
+//      equal to huge for some floating point number "huge" and "tiny".
+//
+//
+// Notes:  Rounding mode detection omitted. The constants "mask", "shift",
+// and "bias" are found in src/math/bits.go
+
+// Sqrt returns the square root of x.
+//
+// Special cases are:
+//
+//	Sqrt(+Inf) = +Inf
+//	Sqrt(±0) = ±0
+//	Sqrt(x < 0) = NaN
+//	Sqrt(NaN) = NaN
+func Sqrt(x float64) float64 {
+	if haveArchSqrt {
+		return archSqrt(x)
+	}
+	return sqrt(x)
+}
+
+// Note: Sqrt is implemented in assembly on some systems.
+// Others have assembly stubs that jump to func sqrt below.
+// On systems where Sqrt is a single instruction, the compiler
+// may turn a direct call into a direct use of that instruction instead.
+
+func sqrt(x float64) float64 {
+	// special cases
+	switch {
+	case x == 0 || IsNaN(x) || IsInf(x, 1):
+		return x
+	case x < 0:
+		return NaN()
+	}
+	ix := Float64bits(x)
+	// normalize x
+	exp := int((ix >> shift) & mask)
+	if exp == 0 { // subnormal x
+		for ix&(1<<shift) == 0 {
+			ix <<= 1
+			exp--
+		}
+		exp++
+	}
+	exp -= bias // unbias exponent
+	ix &^= mask << shift
+	ix |= 1 << shift
+	if exp&1 == 1 { // odd exp, double x to make it even
+		ix <<= 1
+	}
+	exp >>= 1 // exp = exp/2, exponent of square root
+	// generate sqrt(x) bit by bit
+	ix <<= 1
+	var q, s uint64               // q = sqrt(x)
+	r := uint64(1 << (shift + 1)) // r = moving bit from MSB to LSB
+	for r != 0 {
+		t := s + r
+		if t <= ix {
+			s = t + r
+			ix -= t
+			q += r
+		}
+		ix <<= 1
+		r >>= 1
+	}
+	// final rounding
+	if ix != 0 { // remainder, result not exact
+		q += q & 1 // round according to extra bit
+	}
+	ix = q>>1 + uint64(exp-1+bias)<<shift // significand + biased exponent
+	return Float64frombits(ix)
+}
diff --git a/contrib/go/_std_1.18/src/math/sqrt_amd64.s b/contrib/go/_std_1.19/src/math/sqrt_amd64.s
index c3b110e7c0..c3b110e7c0 100644
--- a/contrib/go/_std_1.18/src/math/sqrt_amd64.s
+++ b/contrib/go/_std_1.19/src/math/sqrt_amd64.s
diff --git a/contrib/go/_std_1.18/src/math/sqrt_asm.go b/contrib/go/_std_1.19/src/math/sqrt_asm.go
index 2cec1a5903..2cec1a5903 100644
--- a/contrib/go/_std_1.18/src/math/sqrt_asm.go
+++ b/contrib/go/_std_1.19/src/math/sqrt_asm.go
diff --git a/contrib/go/_std_1.18/src/math/stubs.go b/contrib/go/_std_1.19/src/math/stubs.go
index c4350d4b87..c4350d4b87 100644
--- a/contrib/go/_std_1.18/src/math/stubs.go
+++ b/contrib/go/_std_1.19/src/math/stubs.go
diff --git a/contrib/go/_std_1.19/src/math/tan.go b/contrib/go/_std_1.19/src/math/tan.go
new file mode 100644
index 0000000000..8f6e71e82b
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/tan.go
@@ -0,0 +1,140 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+	Floating-point tangent.
+*/
+
+// The original C code, the long comment, and the constants
+// below were from http://netlib.sandia.gov/cephes/cmath/sin.c,
+// available from http://www.netlib.org/cephes/cmath.tgz.
+// The go code is a simplified version of the original C.
+//
+//      tan.c
+//
+//      Circular tangent
+//
+// SYNOPSIS:
+//
+// double x, y, tan();
+// y = tan( x );
+//
+// DESCRIPTION:
+//
+// Returns the circular tangent of the radian argument x.
+//
+// Range reduction is modulo pi/4.  A rational function
+//       x + x**3 P(x**2)/Q(x**2)
+// is employed in the basic interval [0, pi/4].
+//
+// ACCURACY:
+//                      Relative error:
+// arithmetic   domain     # trials      peak         rms
+//    DEC      +-1.07e9      44000      4.1e-17     1.0e-17
+//    IEEE     +-1.07e9      30000      2.9e-16     8.1e-17
+//
+// Partial loss of accuracy begins to occur at x = 2**30 = 1.074e9.  The loss
+// is not gradual, but jumps suddenly to about 1 part in 10e7.  Results may
+// be meaningless for x > 2**49 = 5.6e14.
+// [Accuracy loss statement from sin.go comments.]
+//
+// Cephes Math Library Release 2.8:  June, 2000
+// Copyright 1984, 1987, 1989, 1992, 2000 by Stephen L. Moshier
+//
+// The readme file at http://netlib.sandia.gov/cephes/ says:
+//    Some software in this archive may be from the book _Methods and
+// Programs for Mathematical Functions_ (Prentice-Hall or Simon & Schuster
+// International, 1989) or from the Cephes Mathematical Library, a
+// commercial product. In either event, it is copyrighted by the author.
+// What you see here may be used freely but it comes with no support or
+// guarantee.
+//
+//   The two known misprints in the book are repaired here in the
+// source listings for the gamma function and the incomplete beta
+// integral.
+//
+//   Stephen L. Moshier
+//   moshier@na-net.ornl.gov
+
+// tan coefficients
+var _tanP = [...]float64{
+	-1.30936939181383777646e4, // 0xc0c992d8d24f3f38
+	1.15351664838587416140e6,  // 0x413199eca5fc9ddd
+	-1.79565251976484877988e7, // 0xc1711fead3299176
+}
+var _tanQ = [...]float64{
+	1.00000000000000000000e0,
+	1.36812963470692954678e4,  // 0x40cab8a5eeb36572
+	-1.32089234440210967447e6, // 0xc13427bc582abc96
+	2.50083801823357915839e7,  // 0x4177d98fc2ead8ef
+	-5.38695755929454629881e7, // 0xc189afe03cbe5a31
+}
+
+// Tan returns the tangent of the radian argument x.
+//
+// Special cases are:
+//
+//	Tan(±0) = ±0
+//	Tan(±Inf) = NaN
+//	Tan(NaN) = NaN
+func Tan(x float64) float64 {
+	if haveArchTan {
+		return archTan(x)
+	}
+	return tan(x)
+}
+
+func tan(x float64) float64 {
+	const (
+		PI4A = 7.85398125648498535156e-1  // 0x3fe921fb40000000, Pi/4 split into three parts
+		PI4B = 3.77489470793079817668e-8  // 0x3e64442d00000000,
+		PI4C = 2.69515142907905952645e-15 // 0x3ce8469898cc5170,
+	)
+	// special cases
+	switch {
+	case x == 0 || IsNaN(x):
+		return x // return ±0 || NaN()
+	case IsInf(x, 0):
+		return NaN()
+	}
+
+	// make argument positive but save the sign
+	sign := false
+	if x < 0 {
+		x = -x
+		sign = true
+	}
+	var j uint64
+	var y, z float64
+	if x >= reduceThreshold {
+		j, z = trigReduce(x)
+	} else {
+		j = uint64(x * (4 / Pi)) // integer part of x/(Pi/4), as integer for tests on the phase angle
+		y = float64(j)           // integer part of x/(Pi/4), as float
+
+		/* map zeros and singularities to origin */
+		if j&1 == 1 {
+			j++
+			y++
+		}
+
+		z = ((x - y*PI4A) - y*PI4B) - y*PI4C
+	}
+	zz := z * z
+
+	if zz > 1e-14 {
+		y = z + z*(zz*(((_tanP[0]*zz)+_tanP[1])*zz+_tanP[2])/((((zz+_tanQ[1])*zz+_tanQ[2])*zz+_tanQ[3])*zz+_tanQ[4]))
+	} else {
+		y = z
+	}
+	if j&2 == 2 {
+		y = -1 / y
+	}
+	if sign {
+		y = -y
+	}
+	return y
+}
diff --git a/contrib/go/_std_1.19/src/math/tanh.go b/contrib/go/_std_1.19/src/math/tanh.go
new file mode 100644
index 0000000000..94ebc3b651
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/tanh.go
@@ -0,0 +1,105 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// The original C code, the long comment, and the constants
+// below were from http://netlib.sandia.gov/cephes/cmath/sin.c,
+// available from http://www.netlib.org/cephes/cmath.tgz.
+// The go code is a simplified version of the original C.
+//      tanh.c
+//
+//      Hyperbolic tangent
+//
+// SYNOPSIS:
+//
+// double x, y, tanh();
+//
+// y = tanh( x );
+//
+// DESCRIPTION:
+//
+// Returns hyperbolic tangent of argument in the range MINLOG to MAXLOG.
+//      MAXLOG = 8.8029691931113054295988e+01 = log(2**127)
+//      MINLOG = -8.872283911167299960540e+01 = log(2**-128)
+//
+// A rational function is used for |x| < 0.625.  The form
+// x + x**3 P(x)/Q(x) of Cody & Waite is employed.
+// Otherwise,
+//      tanh(x) = sinh(x)/cosh(x) = 1  -  2/(exp(2x) + 1).
+//
+// ACCURACY:
+//
+//                      Relative error:
+// arithmetic   domain     # trials      peak         rms
+//    IEEE      -2,2        30000       2.5e-16     5.8e-17
+//
+// Cephes Math Library Release 2.8:  June, 2000
+// Copyright 1984, 1987, 1989, 1992, 2000 by Stephen L. Moshier
+//
+// The readme file at http://netlib.sandia.gov/cephes/ says:
+//    Some software in this archive may be from the book _Methods and
+// Programs for Mathematical Functions_ (Prentice-Hall or Simon & Schuster
+// International, 1989) or from the Cephes Mathematical Library, a
+// commercial product. In either event, it is copyrighted by the author.
+// What you see here may be used freely but it comes with no support or
+// guarantee.
+//
+//   The two known misprints in the book are repaired here in the
+// source listings for the gamma function and the incomplete beta
+// integral.
+//
+//   Stephen L. Moshier
+//   moshier@na-net.ornl.gov
+//
+
+var tanhP = [...]float64{
+	-9.64399179425052238628e-1,
+	-9.92877231001918586564e1,
+	-1.61468768441708447952e3,
+}
+var tanhQ = [...]float64{
+	1.12811678491632931402e2,
+	2.23548839060100448583e3,
+	4.84406305325125486048e3,
+}
+
+// Tanh returns the hyperbolic tangent of x.
+//
+// Special cases are:
+//
+//	Tanh(±0) = ±0
+//	Tanh(±Inf) = ±1
+//	Tanh(NaN) = NaN
+func Tanh(x float64) float64 {
+	if haveArchTanh {
+		return archTanh(x)
+	}
+	return tanh(x)
+}
+
+func tanh(x float64) float64 {
+	const MAXLOG = 8.8029691931113054295988e+01 // log(2**127)
+	z := Abs(x)
+	switch {
+	case z > 0.5*MAXLOG:
+		if x < 0 {
+			return -1
+		}
+		return 1
+	case z >= 0.625:
+		s := Exp(2 * z)
+		z = 1 - 2/(s+1)
+		if x < 0 {
+			z = -z
+		}
+	default:
+		if x == 0 {
+			return x
+		}
+		s := x * x
+		z = x + x*s*((tanhP[0]*s+tanhP[1])*s+tanhP[2])/(((s+tanhQ[0])*s+tanhQ[1])*s+tanhQ[2])
+	}
+	return z
+}
diff --git a/contrib/go/_std_1.19/src/math/trig_reduce.go b/contrib/go/_std_1.19/src/math/trig_reduce.go
new file mode 100644
index 0000000000..5ecdd8375e
--- /dev/null
+++ b/contrib/go/_std_1.19/src/math/trig_reduce.go
@@ -0,0 +1,102 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+import (
+	"math/bits"
+)
+
+// reduceThreshold is the maximum value of x where the reduction using Pi/4
+// in 3 float64 parts still gives accurate results. This threshold
+// is set by y*C being representable as a float64 without error
+// where y is given by y = floor(x * (4 / Pi)) and C is the leading partial
+// terms of 4/Pi. Since the leading terms (PI4A and PI4B in sin.go) have 30
+// and 32 trailing zero bits, y should have less than 30 significant bits.
+//
+//	y < 1<<30  -> floor(x*4/Pi) < 1<<30 -> x < (1<<30 - 1) * Pi/4
+//
+// So, conservatively we can take x < 1<<29.
+// Above this threshold Payne-Hanek range reduction must be used.
+const reduceThreshold = 1 << 29
+
+// trigReduce implements Payne-Hanek range reduction by Pi/4
+// for x > 0. It returns the integer part mod 8 (j) and
+// the fractional part (z) of x / (Pi/4).
+// The implementation is based on:
+// "ARGUMENT REDUCTION FOR HUGE ARGUMENTS: Good to the Last Bit"
+// K. C. Ng et al, March 24, 1992
+// The simulated multi-precision calculation of x*B uses 64-bit integer arithmetic.
+func trigReduce(x float64) (j uint64, z float64) {
+	const PI4 = Pi / 4
+	if x < PI4 {
+		return 0, x
+	}
+	// Extract out the integer and exponent such that,
+	// x = ix * 2 ** exp.
+	ix := Float64bits(x)
+	exp := int(ix>>shift&mask) - bias - shift
+	ix &^= mask << shift
+	ix |= 1 << shift
+	// Use the exponent to extract the 3 appropriate uint64 digits from mPi4,
+	// B ~ (z0, z1, z2), such that the product leading digit has the exponent -61.
+	// Note, exp >= -53 since x >= PI4 and exp < 971 for maximum float64.
+	digit, bitshift := uint(exp+61)/64, uint(exp+61)%64
+	z0 := (mPi4[digit] << bitshift) | (mPi4[digit+1] >> (64 - bitshift))
+	z1 := (mPi4[digit+1] << bitshift) | (mPi4[digit+2] >> (64 - bitshift))
+	z2 := (mPi4[digit+2] << bitshift) | (mPi4[digit+3] >> (64 - bitshift))
+	// Multiply mantissa by the digits and extract the upper two digits (hi, lo).
+	z2hi, _ := bits.Mul64(z2, ix)
+	z1hi, z1lo := bits.Mul64(z1, ix)
+	z0lo := z0 * ix
+	lo, c := bits.Add64(z1lo, z2hi, 0)
+	hi, _ := bits.Add64(z0lo, z1hi, c)
+	// The top 3 bits are j.
+	j = hi >> 61
+	// Extract the fraction and find its magnitude.
+	hi = hi<<3 | lo>>61
+	lz := uint(bits.LeadingZeros64(hi))
+	e := uint64(bias - (lz + 1))
+	// Clear implicit mantissa bit and shift into place.
+	hi = (hi << (lz + 1)) | (lo >> (64 - (lz + 1)))
+	hi >>= 64 - shift
+	// Include the exponent and convert to a float.
+	hi |= e << shift
+	z = Float64frombits(hi)
+	// Map zeros to origin.
+	if j&1 == 1 {
+		j++
+		j &= 7
+		z--
+	}
+	// Multiply the fractional part by pi/4.
+	return j, z * PI4
+}
+
+// mPi4 is the binary digits of 4/pi as a uint64 array,
+// that is, 4/pi = Sum mPi4[i]*2^(-64*i)
+// 19 64-bit digits and the leading one bit give 1217 bits
+// of precision to handle the largest possible float64 exponent.
+var mPi4 = [...]uint64{
+	0x0000000000000001,
+	0x45f306dc9c882a53,
+	0xf84eafa3ea69bb81,
+	0xb6c52b3278872083,
+	0xfca2c757bd778ac3,
+	0x6e48dc74849ba5c0,
+	0x0c925dd413a32439,
+	0xfc3bd63962534e7d,
+	0xd1046bea5d768909,
+	0xd338e04d68befc82,
+	0x7323ac7306a673e9,
+	0x3908bf177bf25076,
+	0x3ff12fffbc0b301f,
+	0xde5e2316b414da3e,
+	0xda6cfd9e4f96136e,
+	0x9e8c7ecd3cbfd45a,
+	0xea4f758fd7cbe2f6,
+	0x7a0e73ef14a525d4,
+	0xd7f6bf623f1aba10,
+	0xac06608df8f6d757,
+}
diff --git a/contrib/go/_std_1.18/src/math/unsafe.go b/contrib/go/_std_1.19/src/math/unsafe.go
index e59f50ca62..e59f50ca62 100644
--- a/contrib/go/_std_1.18/src/math/unsafe.go
+++ b/contrib/go/_std_1.19/src/math/unsafe.go
diff --git a/contrib/go/_std_1.18/src/mime/encodedword.go b/contrib/go/_std_1.19/src/mime/encodedword.go
index e6b470b1fb..e6b470b1fb 100644
--- a/contrib/go/_std_1.18/src/mime/encodedword.go
+++ b/contrib/go/_std_1.19/src/mime/encodedword.go
diff --git a/contrib/go/_std_1.18/src/mime/grammar.go b/contrib/go/_std_1.19/src/mime/grammar.go
index 6a6f71dbd4..6a6f71dbd4 100644
--- a/contrib/go/_std_1.18/src/mime/grammar.go
+++ b/contrib/go/_std_1.19/src/mime/grammar.go
diff --git a/contrib/go/_std_1.18/src/mime/mediatype.go b/contrib/go/_std_1.19/src/mime/mediatype.go
index 6c1b095065..6c1b095065 100644
--- a/contrib/go/_std_1.18/src/mime/mediatype.go
+++ b/contrib/go/_std_1.19/src/mime/mediatype.go
diff --git a/contrib/go/_std_1.18/src/mime/multipart/formdata.go b/contrib/go/_std_1.19/src/mime/multipart/formdata.go
index fca5f9e15f..fca5f9e15f 100644
--- a/contrib/go/_std_1.18/src/mime/multipart/formdata.go
+++ b/contrib/go/_std_1.19/src/mime/multipart/formdata.go
diff --git a/contrib/go/_std_1.19/src/mime/multipart/multipart.go b/contrib/go/_std_1.19/src/mime/multipart/multipart.go
new file mode 100644
index 0000000000..aa05ac8f9c
--- /dev/null
+++ b/contrib/go/_std_1.19/src/mime/multipart/multipart.go
@@ -0,0 +1,447 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+//
+
+/*
+Package multipart implements MIME multipart parsing, as defined in RFC
+2046.
+
+The implementation is sufficient for HTTP (RFC 2388) and the multipart
+bodies generated by popular browsers.
+*/
+package multipart
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"io"
+	"mime"
+	"mime/quotedprintable"
+	"net/textproto"
+	"path/filepath"
+	"strings"
+)
+
+var emptyParams = make(map[string]string)
+
+// This constant needs to be at least 76 for this package to work correctly.
+// This is because \r\n--separator_of_len_70- would fill the buffer and it
+// wouldn't be safe to consume a single byte from it.
+const peekBufferSize = 4096
+
+// A Part represents a single part in a multipart body.
+type Part struct {
+	// The headers of the body, if any, with the keys canonicalized
+	// in the same fashion that the Go http.Request headers are.
+	// For example, "foo-bar" changes case to "Foo-Bar"
+	Header textproto.MIMEHeader
+
+	mr *Reader
+
+	disposition       string
+	dispositionParams map[string]string
+
+	// r is either a reader directly reading from mr, or it's a
+	// wrapper around such a reader, decoding the
+	// Content-Transfer-Encoding
+	r io.Reader
+
+	n       int   // known data bytes waiting in mr.bufReader
+	total   int64 // total data bytes read already
+	err     error // error to return when n == 0
+	readErr error // read error observed from mr.bufReader
+}
+
+// FormName returns the name parameter if p has a Content-Disposition
+// of type "form-data".  Otherwise it returns the empty string.
+func (p *Part) FormName() string {
+	// See https://tools.ietf.org/html/rfc2183 section 2 for EBNF
+	// of Content-Disposition value format.
+	if p.dispositionParams == nil {
+		p.parseContentDisposition()
+	}
+	if p.disposition != "form-data" {
+		return ""
+	}
+	return p.dispositionParams["name"]
+}
+
+// FileName returns the filename parameter of the Part's Content-Disposition
+// header. If not empty, the filename is passed through filepath.Base (which is
+// platform dependent) before being returned.
+func (p *Part) FileName() string {
+	if p.dispositionParams == nil {
+		p.parseContentDisposition()
+	}
+	filename := p.dispositionParams["filename"]
+	if filename == "" {
+		return ""
+	}
+	// RFC 7578, Section 4.2 requires that if a filename is provided, the
+	// directory path information must not be used.
+	return filepath.Base(filename)
+}
+
+func (p *Part) parseContentDisposition() {
+	v := p.Header.Get("Content-Disposition")
+	var err error
+	p.disposition, p.dispositionParams, err = mime.ParseMediaType(v)
+	if err != nil {
+		p.dispositionParams = emptyParams
+	}
+}
+
+// NewReader creates a new multipart Reader reading from r using the
+// given MIME boundary.
+//
+// The boundary is usually obtained from the "boundary" parameter of
+// the message's "Content-Type" header. Use mime.ParseMediaType to
+// parse such headers.
+func NewReader(r io.Reader, boundary string) *Reader {
+	b := []byte("\r\n--" + boundary + "--")
+	return &Reader{
+		bufReader:        bufio.NewReaderSize(&stickyErrorReader{r: r}, peekBufferSize),
+		nl:               b[:2],
+		nlDashBoundary:   b[:len(b)-2],
+		dashBoundaryDash: b[2:],
+		dashBoundary:     b[2 : len(b)-2],
+	}
+}
+
+// stickyErrorReader is an io.Reader which never calls Read on its
+// underlying Reader once an error has been seen. (the io.Reader
+// interface's contract promises nothing about the return values of
+// Read calls after an error, yet this package does do multiple Reads
+// after error)
+type stickyErrorReader struct {
+	r   io.Reader
+	err error
+}
+
+func (r *stickyErrorReader) Read(p []byte) (n int, _ error) {
+	if r.err != nil {
+		return 0, r.err
+	}
+	n, r.err = r.r.Read(p)
+	return n, r.err
+}
+
+func newPart(mr *Reader, rawPart bool) (*Part, error) {
+	bp := &Part{
+		Header: make(map[string][]string),
+		mr:     mr,
+	}
+	if err := bp.populateHeaders(); err != nil {
+		return nil, err
+	}
+	bp.r = partReader{bp}
+
+	// rawPart is used to switch between Part.NextPart and Part.NextRawPart.
+	if !rawPart {
+		const cte = "Content-Transfer-Encoding"
+		if strings.EqualFold(bp.Header.Get(cte), "quoted-printable") {
+			bp.Header.Del(cte)
+			bp.r = quotedprintable.NewReader(bp.r)
+		}
+	}
+	return bp, nil
+}
+
+func (p *Part) populateHeaders() error {
+	r := textproto.NewReader(p.mr.bufReader)
+	header, err := r.ReadMIMEHeader()
+	if err == nil {
+		p.Header = header
+	}
+	return err
+}
+
+// Read reads the body of a part, after its headers and before the
+// next part (if any) begins.
+func (p *Part) Read(d []byte) (n int, err error) {
+	return p.r.Read(d)
+}
+
+// partReader implements io.Reader by reading raw bytes directly from the
+// wrapped *Part, without doing any Transfer-Encoding decoding.
+type partReader struct {
+	p *Part
+}
+
+func (pr partReader) Read(d []byte) (int, error) {
+	p := pr.p
+	br := p.mr.bufReader
+
+	// Read into buffer until we identify some data to return,
+	// or we find a reason to stop (boundary or read error).
+	for p.n == 0 && p.err == nil {
+		peek, _ := br.Peek(br.Buffered())
+		p.n, p.err = scanUntilBoundary(peek, p.mr.dashBoundary, p.mr.nlDashBoundary, p.total, p.readErr)
+		if p.n == 0 && p.err == nil {
+			// Force buffered I/O to read more into buffer.
+			_, p.readErr = br.Peek(len(peek) + 1)
+			if p.readErr == io.EOF {
+				p.readErr = io.ErrUnexpectedEOF
+			}
+		}
+	}
+
+	// Read out from "data to return" part of buffer.
+	if p.n == 0 {
+		return 0, p.err
+	}
+	n := len(d)
+	if n > p.n {
+		n = p.n
+	}
+	n, _ = br.Read(d[:n])
+	p.total += int64(n)
+	p.n -= n
+	if p.n == 0 {
+		return n, p.err
+	}
+	return n, nil
+}
+
+// scanUntilBoundary scans buf to identify how much of it can be safely
+// returned as part of the Part body.
+// dashBoundary is "--boundary".
+// nlDashBoundary is "\r\n--boundary" or "\n--boundary", depending on what mode we are in.
+// The comments below (and the name) assume "\n--boundary", but either is accepted.
+// total is the number of bytes read out so far. If total == 0, then a leading "--boundary" is recognized.
+// readErr is the read error, if any, that followed reading the bytes in buf.
+// scanUntilBoundary returns the number of data bytes from buf that can be
+// returned as part of the Part body and also the error to return (if any)
+// once those data bytes are done.
+func scanUntilBoundary(buf, dashBoundary, nlDashBoundary []byte, total int64, readErr error) (int, error) {
+	if total == 0 {
+		// At beginning of body, allow dashBoundary.
+		if bytes.HasPrefix(buf, dashBoundary) {
+			switch matchAfterPrefix(buf, dashBoundary, readErr) {
+			case -1:
+				return len(dashBoundary), nil
+			case 0:
+				return 0, nil
+			case +1:
+				return 0, io.EOF
+			}
+		}
+		if bytes.HasPrefix(dashBoundary, buf) {
+			return 0, readErr
+		}
+	}
+
+	// Search for "\n--boundary".
+	if i := bytes.Index(buf, nlDashBoundary); i >= 0 {
+		switch matchAfterPrefix(buf[i:], nlDashBoundary, readErr) {
+		case -1:
+			return i + len(nlDashBoundary), nil
+		case 0:
+			return i, nil
+		case +1:
+			return i, io.EOF
+		}
+	}
+	if bytes.HasPrefix(nlDashBoundary, buf) {
+		return 0, readErr
+	}
+
+	// Otherwise, anything up to the final \n is not part of the boundary
+	// and so must be part of the body.
+	// Also if the section from the final \n onward is not a prefix of the boundary,
+	// it too must be part of the body.
+	i := bytes.LastIndexByte(buf, nlDashBoundary[0])
+	if i >= 0 && bytes.HasPrefix(nlDashBoundary, buf[i:]) {
+		return i, nil
+	}
+	return len(buf), readErr
+}
+
+// matchAfterPrefix checks whether buf should be considered to match the boundary.
+// The prefix is "--boundary" or "\r\n--boundary" or "\n--boundary",
+// and the caller has verified already that bytes.HasPrefix(buf, prefix) is true.
+//
+// matchAfterPrefix returns +1 if the buffer does match the boundary,
+// meaning the prefix is followed by a double dash, space, tab, cr, nl,
+// or end of input.
+// It returns -1 if the buffer definitely does NOT match the boundary,
+// meaning the prefix is followed by some other character.
+// For example, "--foobar" does not match "--foo".
+// It returns 0 more input needs to be read to make the decision,
+// meaning that len(buf) == len(prefix) and readErr == nil.
+func matchAfterPrefix(buf, prefix []byte, readErr error) int {
+	if len(buf) == len(prefix) {
+		if readErr != nil {
+			return +1
+		}
+		return 0
+	}
+	c := buf[len(prefix)]
+
+	if c == ' ' || c == '\t' || c == '\r' || c == '\n' {
+		return +1
+	}
+
+	// Try to detect boundaryDash
+	if c == '-' {
+		if len(buf) == len(prefix)+1 {
+			if readErr != nil {
+				// Prefix + "-" does not match
+				return -1
+			}
+			return 0
+		}
+		if buf[len(prefix)+1] == '-' {
+			return +1
+		}
+	}
+
+	return -1
+}
+
+func (p *Part) Close() error {
+	io.Copy(io.Discard, p)
+	return nil
+}
+
+// Reader is an iterator over parts in a MIME multipart body.
+// Reader's underlying parser consumes its input as needed. Seeking
+// isn't supported.
+type Reader struct {
+	bufReader *bufio.Reader
+
+	currentPart *Part
+	partsRead   int
+
+	nl               []byte // "\r\n" or "\n" (set after seeing first boundary line)
+	nlDashBoundary   []byte // nl + "--boundary"
+	dashBoundaryDash []byte // "--boundary--"
+	dashBoundary     []byte // "--boundary"
+}
+
+// NextPart returns the next part in the multipart or an error.
+// When there are no more parts, the error io.EOF is returned.
+//
+// As a special case, if the "Content-Transfer-Encoding" header
+// has a value of "quoted-printable", that header is instead
+// hidden and the body is transparently decoded during Read calls.
+func (r *Reader) NextPart() (*Part, error) {
+	return r.nextPart(false)
+}
+
+// NextRawPart returns the next part in the multipart or an error.
+// When there are no more parts, the error io.EOF is returned.
+//
+// Unlike NextPart, it does not have special handling for
+// "Content-Transfer-Encoding: quoted-printable".
+func (r *Reader) NextRawPart() (*Part, error) {
+	return r.nextPart(true)
+}
+
+func (r *Reader) nextPart(rawPart bool) (*Part, error) {
+	if r.currentPart != nil {
+		r.currentPart.Close()
+	}
+	if string(r.dashBoundary) == "--" {
+		return nil, fmt.Errorf("multipart: boundary is empty")
+	}
+	expectNewPart := false
+	for {
+		line, err := r.bufReader.ReadSlice('\n')
+
+		if err == io.EOF && r.isFinalBoundary(line) {
+			// If the buffer ends in "--boundary--" without the
+			// trailing "\r\n", ReadSlice will return an error
+			// (since it's missing the '\n'), but this is a valid
+			// multipart EOF so we need to return io.EOF instead of
+			// a fmt-wrapped one.
+			return nil, io.EOF
+		}
+		if err != nil {
+			return nil, fmt.Errorf("multipart: NextPart: %v", err)
+		}
+
+		if r.isBoundaryDelimiterLine(line) {
+			r.partsRead++
+			bp, err := newPart(r, rawPart)
+			if err != nil {
+				return nil, err
+			}
+			r.currentPart = bp
+			return bp, nil
+		}
+
+		if r.isFinalBoundary(line) {
+			// Expected EOF
+			return nil, io.EOF
+		}
+
+		if expectNewPart {
+			return nil, fmt.Errorf("multipart: expecting a new Part; got line %q", string(line))
+		}
+
+		if r.partsRead == 0 {
+			// skip line
+			continue
+		}
+
+		// Consume the "\n" or "\r\n" separator between the
+		// body of the previous part and the boundary line we
+		// now expect will follow. (either a new part or the
+		// end boundary)
+		if bytes.Equal(line, r.nl) {
+			expectNewPart = true
+			continue
+		}
+
+		return nil, fmt.Errorf("multipart: unexpected line in Next(): %q", line)
+	}
+}
+
+// isFinalBoundary reports whether line is the final boundary line
+// indicating that all parts are over.
+// It matches `^--boundary--[ \t]*(\r\n)?$`
+func (r *Reader) isFinalBoundary(line []byte) bool {
+	if !bytes.HasPrefix(line, r.dashBoundaryDash) {
+		return false
+	}
+	rest := line[len(r.dashBoundaryDash):]
+	rest = skipLWSPChar(rest)
+	return len(rest) == 0 || bytes.Equal(rest, r.nl)
+}
+
+func (r *Reader) isBoundaryDelimiterLine(line []byte) (ret bool) {
+	// https://tools.ietf.org/html/rfc2046#section-5.1
+	//   The boundary delimiter line is then defined as a line
+	//   consisting entirely of two hyphen characters ("-",
+	//   decimal value 45) followed by the boundary parameter
+	//   value from the Content-Type header field, optional linear
+	//   whitespace, and a terminating CRLF.
+	if !bytes.HasPrefix(line, r.dashBoundary) {
+		return false
+	}
+	rest := line[len(r.dashBoundary):]
+	rest = skipLWSPChar(rest)
+
+	// On the first part, see our lines are ending in \n instead of \r\n
+	// and switch into that mode if so. This is a violation of the spec,
+	// but occurs in practice.
+	if r.partsRead == 0 && len(rest) == 1 && rest[0] == '\n' {
+		r.nl = r.nl[1:]
+		r.nlDashBoundary = r.nlDashBoundary[1:]
+	}
+	return bytes.Equal(rest, r.nl)
+}
+
+// skipLWSPChar returns b with leading spaces and tabs removed.
+// RFC 822 defines:
+//
+//	LWSP-char = SPACE / HTAB
+func skipLWSPChar(b []byte) []byte {
+	for len(b) > 0 && (b[0] == ' ' || b[0] == '\t') {
+		b = b[1:]
+	}
+	return b
+}
diff --git a/contrib/go/_std_1.18/src/mime/multipart/writer.go b/contrib/go/_std_1.19/src/mime/multipart/writer.go
index d1ff151a7d..d1ff151a7d 100644
--- a/contrib/go/_std_1.18/src/mime/multipart/writer.go
+++ b/contrib/go/_std_1.19/src/mime/multipart/writer.go
diff --git a/contrib/go/_std_1.18/src/mime/quotedprintable/reader.go b/contrib/go/_std_1.19/src/mime/quotedprintable/reader.go
index 4239625402..4239625402 100644
--- a/contrib/go/_std_1.18/src/mime/quotedprintable/reader.go
+++ b/contrib/go/_std_1.19/src/mime/quotedprintable/reader.go
diff --git a/contrib/go/_std_1.18/src/mime/quotedprintable/writer.go b/contrib/go/_std_1.19/src/mime/quotedprintable/writer.go
index 16ea0bf7d6..16ea0bf7d6 100644
--- a/contrib/go/_std_1.18/src/mime/quotedprintable/writer.go
+++ b/contrib/go/_std_1.19/src/mime/quotedprintable/writer.go
diff --git a/contrib/go/_std_1.19/src/mime/type.go b/contrib/go/_std_1.19/src/mime/type.go
new file mode 100644
index 0000000000..465ecf0d59
--- /dev/null
+++ b/contrib/go/_std_1.19/src/mime/type.go
@@ -0,0 +1,202 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package mime implements parts of the MIME spec.
+package mime
+
+import (
+	"fmt"
+	"sort"
+	"strings"
+	"sync"
+)
+
+var (
+	mimeTypes      sync.Map // map[string]string; ".Z" => "application/x-compress"
+	mimeTypesLower sync.Map // map[string]string; ".z" => "application/x-compress"
+
+	// extensions maps from MIME type to list of lowercase file
+	// extensions: "image/jpeg" => [".jpg", ".jpeg"]
+	extensionsMu sync.Mutex // Guards stores (but not loads) on extensions.
+	extensions   sync.Map   // map[string][]string; slice values are append-only.
+)
+
+func clearSyncMap(m *sync.Map) {
+	m.Range(func(k, _ any) bool {
+		m.Delete(k)
+		return true
+	})
+}
+
+// setMimeTypes is used by initMime's non-test path, and by tests.
+func setMimeTypes(lowerExt, mixExt map[string]string) {
+	clearSyncMap(&mimeTypes)
+	clearSyncMap(&mimeTypesLower)
+	clearSyncMap(&extensions)
+
+	for k, v := range lowerExt {
+		mimeTypesLower.Store(k, v)
+	}
+	for k, v := range mixExt {
+		mimeTypes.Store(k, v)
+	}
+
+	extensionsMu.Lock()
+	defer extensionsMu.Unlock()
+	for k, v := range lowerExt {
+		justType, _, err := ParseMediaType(v)
+		if err != nil {
+			panic(err)
+		}
+		var exts []string
+		if ei, ok := extensions.Load(justType); ok {
+			exts = ei.([]string)
+		}
+		extensions.Store(justType, append(exts, k))
+	}
+}
+
+var builtinTypesLower = map[string]string{
+	".avif": "image/avif",
+	".css":  "text/css; charset=utf-8",
+	".gif":  "image/gif",
+	".htm":  "text/html; charset=utf-8",
+	".html": "text/html; charset=utf-8",
+	".jpeg": "image/jpeg",
+	".jpg":  "image/jpeg",
+	".js":   "text/javascript; charset=utf-8",
+	".json": "application/json",
+	".mjs":  "text/javascript; charset=utf-8",
+	".pdf":  "application/pdf",
+	".png":  "image/png",
+	".svg":  "image/svg+xml",
+	".wasm": "application/wasm",
+	".webp": "image/webp",
+	".xml":  "text/xml; charset=utf-8",
+}
+
+var once sync.Once // guards initMime
+
+var testInitMime, osInitMime func()
+
+func initMime() {
+	if fn := testInitMime; fn != nil {
+		fn()
+	} else {
+		setMimeTypes(builtinTypesLower, builtinTypesLower)
+		osInitMime()
+	}
+}
+
+// TypeByExtension returns the MIME type associated with the file extension ext.
+// The extension ext should begin with a leading dot, as in ".html".
+// When ext has no associated type, TypeByExtension returns "".
+//
+// Extensions are looked up first case-sensitively, then case-insensitively.
+//
+// The built-in table is small but on unix it is augmented by the local
+// system's MIME-info database or mime.types file(s) if available under one or
+// more of these names:
+//
+//	/usr/local/share/mime/globs2
+//	/usr/share/mime/globs2
+//	/etc/mime.types
+//	/etc/apache2/mime.types
+//	/etc/apache/mime.types
+//
+// On Windows, MIME types are extracted from the registry.
+//
+// Text types have the charset parameter set to "utf-8" by default.
+func TypeByExtension(ext string) string {
+	once.Do(initMime)
+
+	// Case-sensitive lookup.
+	if v, ok := mimeTypes.Load(ext); ok {
+		return v.(string)
+	}
+
+	// Case-insensitive lookup.
+	// Optimistically assume a short ASCII extension and be
+	// allocation-free in that case.
+	var buf [10]byte
+	lower := buf[:0]
+	const utf8RuneSelf = 0x80 // from utf8 package, but not importing it.
+	for i := 0; i < len(ext); i++ {
+		c := ext[i]
+		if c >= utf8RuneSelf {
+			// Slow path.
+			si, _ := mimeTypesLower.Load(strings.ToLower(ext))
+			s, _ := si.(string)
+			return s
+		}
+		if 'A' <= c && c <= 'Z' {
+			lower = append(lower, c+('a'-'A'))
+		} else {
+			lower = append(lower, c)
+		}
+	}
+	si, _ := mimeTypesLower.Load(string(lower))
+	s, _ := si.(string)
+	return s
+}
+
+// ExtensionsByType returns the extensions known to be associated with the MIME
+// type typ. The returned extensions will each begin with a leading dot, as in
+// ".html". When typ has no associated extensions, ExtensionsByType returns an
+// nil slice.
+func ExtensionsByType(typ string) ([]string, error) {
+	justType, _, err := ParseMediaType(typ)
+	if err != nil {
+		return nil, err
+	}
+
+	once.Do(initMime)
+	s, ok := extensions.Load(justType)
+	if !ok {
+		return nil, nil
+	}
+	ret := append([]string(nil), s.([]string)...)
+	sort.Strings(ret)
+	return ret, nil
+}
+
+// AddExtensionType sets the MIME type associated with
+// the extension ext to typ. The extension should begin with
+// a leading dot, as in ".html".
+func AddExtensionType(ext, typ string) error {
+	if !strings.HasPrefix(ext, ".") {
+		return fmt.Errorf("mime: extension %q missing leading dot", ext)
+	}
+	once.Do(initMime)
+	return setExtensionType(ext, typ)
+}
+
+func setExtensionType(extension, mimeType string) error {
+	justType, param, err := ParseMediaType(mimeType)
+	if err != nil {
+		return err
+	}
+	if strings.HasPrefix(mimeType, "text/") && param["charset"] == "" {
+		param["charset"] = "utf-8"
+		mimeType = FormatMediaType(mimeType, param)
+	}
+	extLower := strings.ToLower(extension)
+
+	mimeTypes.Store(extension, mimeType)
+	mimeTypesLower.Store(extLower, mimeType)
+
+	extensionsMu.Lock()
+	defer extensionsMu.Unlock()
+	var exts []string
+	if ei, ok := extensions.Load(justType); ok {
+		exts = ei.([]string)
+	}
+	for _, v := range exts {
+		if v == extLower {
+			return nil
+		}
+	}
+	extensions.Store(justType, append(exts, extLower))
+	return nil
+}
diff --git a/contrib/go/_std_1.19/src/mime/type_unix.go b/contrib/go/_std_1.19/src/mime/type_unix.go
new file mode 100644
index 0000000000..649d9001e3
--- /dev/null
+++ b/contrib/go/_std_1.19/src/mime/type_unix.go
@@ -0,0 +1,126 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm)
+
+package mime
+
+import (
+	"bufio"
+	"os"
+	"strings"
+)
+
+func init() {
+	osInitMime = initMimeUnix
+}
+
+// See https://specifications.freedesktop.org/shared-mime-info-spec/shared-mime-info-spec-0.21.html
+// for the FreeDesktop Shared MIME-info Database specification.
+var mimeGlobs = []string{
+	"/usr/local/share/mime/globs2",
+	"/usr/share/mime/globs2",
+}
+
+// Common locations for mime.types files on unix.
+var typeFiles = []string{
+	"/etc/mime.types",
+	"/etc/apache2/mime.types",
+	"/etc/apache/mime.types",
+	"/etc/httpd/conf/mime.types",
+}
+
+func loadMimeGlobsFile(filename string) error {
+	f, err := os.Open(filename)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	scanner := bufio.NewScanner(f)
+	for scanner.Scan() {
+		// Each line should be of format: weight:mimetype:glob[:morefields...]
+		fields := strings.Split(scanner.Text(), ":")
+		if len(fields) < 3 || len(fields[0]) < 1 || len(fields[2]) < 3 {
+			continue
+		} else if fields[0][0] == '#' || fields[2][0] != '*' || fields[2][1] != '.' {
+			continue
+		}
+
+		extension := fields[2][1:]
+		if strings.ContainsAny(extension, "?*[") {
+			// Not a bare extension, but a glob. Ignore for now:
+			// - we do not have an implementation for this glob
+			//   syntax (translation to path/filepath.Match could
+			//   be possible)
+			// - support for globs with weight ordering would have
+			//   performance impact to all lookups to support the
+			//   rarely seen glob entries
+			// - trying to match glob metacharacters literally is
+			//   not useful
+			continue
+		}
+		if _, ok := mimeTypes.Load(extension); ok {
+			// We've already seen this extension.
+			// The file is in weight order, so we keep
+			// the first entry that we see.
+			continue
+		}
+
+		setExtensionType(extension, fields[1])
+	}
+	if err := scanner.Err(); err != nil {
+		panic(err)
+	}
+	return nil
+}
+
+func loadMimeFile(filename string) {
+	f, err := os.Open(filename)
+	if err != nil {
+		return
+	}
+	defer f.Close()
+
+	scanner := bufio.NewScanner(f)
+	for scanner.Scan() {
+		fields := strings.Fields(scanner.Text())
+		if len(fields) <= 1 || fields[0][0] == '#' {
+			continue
+		}
+		mimeType := fields[0]
+		for _, ext := range fields[1:] {
+			if ext[0] == '#' {
+				break
+			}
+			setExtensionType("."+ext, mimeType)
+		}
+	}
+	if err := scanner.Err(); err != nil {
+		panic(err)
+	}
+}
+
+func initMimeUnix() {
+	for _, filename := range mimeGlobs {
+		if err := loadMimeGlobsFile(filename); err == nil {
+			return // Stop checking more files if mimetype database is found.
+		}
+	}
+
+	// Fallback if no system-generated mimetype database exists.
+	for _, filename := range typeFiles {
+		loadMimeFile(filename)
+	}
+}
+
+func initMimeForTests() map[string]string {
+	mimeGlobs = []string{""}
+	typeFiles = []string{"testdata/test.types"}
+	return map[string]string{
+		".T1":  "application/test",
+		".t2":  "text/test; charset=utf-8",
+		".png": "image/png",
+	}
+}
diff --git a/contrib/go/_std_1.19/src/net/addrselect.go b/contrib/go/_std_1.19/src/net/addrselect.go
new file mode 100644
index 0000000000..59380b9486
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/addrselect.go
@@ -0,0 +1,388 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Minimal RFC 6724 address selection.
+
+package net
+
+import "sort"
+
+func sortByRFC6724(addrs []IPAddr) {
+	if len(addrs) < 2 {
+		return
+	}
+	sortByRFC6724withSrcs(addrs, srcAddrs(addrs))
+}
+
+func sortByRFC6724withSrcs(addrs []IPAddr, srcs []IP) {
+	if len(addrs) != len(srcs) {
+		panic("internal error")
+	}
+	addrAttr := make([]ipAttr, len(addrs))
+	srcAttr := make([]ipAttr, len(srcs))
+	for i, v := range addrs {
+		addrAttr[i] = ipAttrOf(v.IP)
+		srcAttr[i] = ipAttrOf(srcs[i])
+	}
+	sort.Stable(&byRFC6724{
+		addrs:    addrs,
+		addrAttr: addrAttr,
+		srcs:     srcs,
+		srcAttr:  srcAttr,
+	})
+}
+
+// srcsAddrs tries to UDP-connect to each address to see if it has a
+// route. (This doesn't send any packets). The destination port
+// number is irrelevant.
+func srcAddrs(addrs []IPAddr) []IP {
+	srcs := make([]IP, len(addrs))
+	dst := UDPAddr{Port: 9}
+	for i := range addrs {
+		dst.IP = addrs[i].IP
+		dst.Zone = addrs[i].Zone
+		c, err := DialUDP("udp", nil, &dst)
+		if err == nil {
+			if src, ok := c.LocalAddr().(*UDPAddr); ok {
+				srcs[i] = src.IP
+			}
+			c.Close()
+		}
+	}
+	return srcs
+}
+
+type ipAttr struct {
+	Scope      scope
+	Precedence uint8
+	Label      uint8
+}
+
+func ipAttrOf(ip IP) ipAttr {
+	if ip == nil {
+		return ipAttr{}
+	}
+	match := rfc6724policyTable.Classify(ip)
+	return ipAttr{
+		Scope:      classifyScope(ip),
+		Precedence: match.Precedence,
+		Label:      match.Label,
+	}
+}
+
+type byRFC6724 struct {
+	addrs    []IPAddr // addrs to sort
+	addrAttr []ipAttr
+	srcs     []IP // or nil if unreachable
+	srcAttr  []ipAttr
+}
+
+func (s *byRFC6724) Len() int { return len(s.addrs) }
+
+func (s *byRFC6724) Swap(i, j int) {
+	s.addrs[i], s.addrs[j] = s.addrs[j], s.addrs[i]
+	s.srcs[i], s.srcs[j] = s.srcs[j], s.srcs[i]
+	s.addrAttr[i], s.addrAttr[j] = s.addrAttr[j], s.addrAttr[i]
+	s.srcAttr[i], s.srcAttr[j] = s.srcAttr[j], s.srcAttr[i]
+}
+
+// Less reports whether i is a better destination address for this
+// host than j.
+//
+// The algorithm and variable names comes from RFC 6724 section 6.
+func (s *byRFC6724) Less(i, j int) bool {
+	DA := s.addrs[i].IP
+	DB := s.addrs[j].IP
+	SourceDA := s.srcs[i]
+	SourceDB := s.srcs[j]
+	attrDA := &s.addrAttr[i]
+	attrDB := &s.addrAttr[j]
+	attrSourceDA := &s.srcAttr[i]
+	attrSourceDB := &s.srcAttr[j]
+
+	const preferDA = true
+	const preferDB = false
+
+	// Rule 1: Avoid unusable destinations.
+	// If DB is known to be unreachable or if Source(DB) is undefined, then
+	// prefer DA.  Similarly, if DA is known to be unreachable or if
+	// Source(DA) is undefined, then prefer DB.
+	if SourceDA == nil && SourceDB == nil {
+		return false // "equal"
+	}
+	if SourceDB == nil {
+		return preferDA
+	}
+	if SourceDA == nil {
+		return preferDB
+	}
+
+	// Rule 2: Prefer matching scope.
+	// If Scope(DA) = Scope(Source(DA)) and Scope(DB) <> Scope(Source(DB)),
+	// then prefer DA.  Similarly, if Scope(DA) <> Scope(Source(DA)) and
+	// Scope(DB) = Scope(Source(DB)), then prefer DB.
+	if attrDA.Scope == attrSourceDA.Scope && attrDB.Scope != attrSourceDB.Scope {
+		return preferDA
+	}
+	if attrDA.Scope != attrSourceDA.Scope && attrDB.Scope == attrSourceDB.Scope {
+		return preferDB
+	}
+
+	// Rule 3: Avoid deprecated addresses.
+	// If Source(DA) is deprecated and Source(DB) is not, then prefer DB.
+	// Similarly, if Source(DA) is not deprecated and Source(DB) is
+	// deprecated, then prefer DA.
+
+	// TODO(bradfitz): implement? low priority for now.
+
+	// Rule 4: Prefer home addresses.
+	// If Source(DA) is simultaneously a home address and care-of address
+	// and Source(DB) is not, then prefer DA.  Similarly, if Source(DB) is
+	// simultaneously a home address and care-of address and Source(DA) is
+	// not, then prefer DB.
+
+	// TODO(bradfitz): implement? low priority for now.
+
+	// Rule 5: Prefer matching label.
+	// If Label(Source(DA)) = Label(DA) and Label(Source(DB)) <> Label(DB),
+	// then prefer DA.  Similarly, if Label(Source(DA)) <> Label(DA) and
+	// Label(Source(DB)) = Label(DB), then prefer DB.
+	if attrSourceDA.Label == attrDA.Label &&
+		attrSourceDB.Label != attrDB.Label {
+		return preferDA
+	}
+	if attrSourceDA.Label != attrDA.Label &&
+		attrSourceDB.Label == attrDB.Label {
+		return preferDB
+	}
+
+	// Rule 6: Prefer higher precedence.
+	// If Precedence(DA) > Precedence(DB), then prefer DA.  Similarly, if
+	// Precedence(DA) < Precedence(DB), then prefer DB.
+	if attrDA.Precedence > attrDB.Precedence {
+		return preferDA
+	}
+	if attrDA.Precedence < attrDB.Precedence {
+		return preferDB
+	}
+
+	// Rule 7: Prefer native transport.
+	// If DA is reached via an encapsulating transition mechanism (e.g.,
+	// IPv6 in IPv4) and DB is not, then prefer DB.  Similarly, if DB is
+	// reached via encapsulation and DA is not, then prefer DA.
+
+	// TODO(bradfitz): implement? low priority for now.
+
+	// Rule 8: Prefer smaller scope.
+	// If Scope(DA) < Scope(DB), then prefer DA.  Similarly, if Scope(DA) >
+	// Scope(DB), then prefer DB.
+	if attrDA.Scope < attrDB.Scope {
+		return preferDA
+	}
+	if attrDA.Scope > attrDB.Scope {
+		return preferDB
+	}
+
+	// Rule 9: Use longest matching prefix.
+	// When DA and DB belong to the same address family (both are IPv6 or
+	// both are IPv4 [but see below]): If CommonPrefixLen(Source(DA), DA) >
+	// CommonPrefixLen(Source(DB), DB), then prefer DA.  Similarly, if
+	// CommonPrefixLen(Source(DA), DA) < CommonPrefixLen(Source(DB), DB),
+	// then prefer DB.
+	//
+	// However, applying this rule to IPv4 addresses causes
+	// problems (see issues 13283 and 18518), so limit to IPv6.
+	if DA.To4() == nil && DB.To4() == nil {
+		commonA := commonPrefixLen(SourceDA, DA)
+		commonB := commonPrefixLen(SourceDB, DB)
+
+		if commonA > commonB {
+			return preferDA
+		}
+		if commonA < commonB {
+			return preferDB
+		}
+	}
+
+	// Rule 10: Otherwise, leave the order unchanged.
+	// If DA preceded DB in the original list, prefer DA.
+	// Otherwise, prefer DB.
+	return false // "equal"
+}
+
+type policyTableEntry struct {
+	Prefix     *IPNet
+	Precedence uint8
+	Label      uint8
+}
+
+type policyTable []policyTableEntry
+
+// RFC 6724 section 2.1.
+var rfc6724policyTable = policyTable{
+	{
+		Prefix:     mustCIDR("::1/128"),
+		Precedence: 50,
+		Label:      0,
+	},
+	{
+		Prefix:     mustCIDR("::/0"),
+		Precedence: 40,
+		Label:      1,
+	},
+	{
+		// IPv4-compatible, etc.
+		Prefix:     mustCIDR("::ffff:0:0/96"),
+		Precedence: 35,
+		Label:      4,
+	},
+	{
+		// 6to4
+		Prefix:     mustCIDR("2002::/16"),
+		Precedence: 30,
+		Label:      2,
+	},
+	{
+		// Teredo
+		Prefix:     mustCIDR("2001::/32"),
+		Precedence: 5,
+		Label:      5,
+	},
+	{
+		Prefix:     mustCIDR("fc00::/7"),
+		Precedence: 3,
+		Label:      13,
+	},
+	{
+		Prefix:     mustCIDR("::/96"),
+		Precedence: 1,
+		Label:      3,
+	},
+	{
+		Prefix:     mustCIDR("fec0::/10"),
+		Precedence: 1,
+		Label:      11,
+	},
+	{
+		Prefix:     mustCIDR("3ffe::/16"),
+		Precedence: 1,
+		Label:      12,
+	},
+}
+
+func init() {
+	sort.Sort(sort.Reverse(byMaskLength(rfc6724policyTable)))
+}
+
+// byMaskLength sorts policyTableEntry by the size of their Prefix.Mask.Size,
+// from smallest mask, to largest.
+type byMaskLength []policyTableEntry
+
+func (s byMaskLength) Len() int      { return len(s) }
+func (s byMaskLength) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
+func (s byMaskLength) Less(i, j int) bool {
+	isize, _ := s[i].Prefix.Mask.Size()
+	jsize, _ := s[j].Prefix.Mask.Size()
+	return isize < jsize
+}
+
+// mustCIDR calls ParseCIDR and panics on any error, or if the network
+// is not IPv6.
+func mustCIDR(s string) *IPNet {
+	ip, ipNet, err := ParseCIDR(s)
+	if err != nil {
+		panic(err.Error())
+	}
+	if len(ip) != IPv6len {
+		panic("unexpected IP length")
+	}
+	return ipNet
+}
+
+// Classify returns the policyTableEntry of the entry with the longest
+// matching prefix that contains ip.
+// The table t must be sorted from largest mask size to smallest.
+func (t policyTable) Classify(ip IP) policyTableEntry {
+	for _, ent := range t {
+		if ent.Prefix.Contains(ip) {
+			return ent
+		}
+	}
+	return policyTableEntry{}
+}
+
+// RFC 6724 section 3.1.
+type scope uint8
+
+const (
+	scopeInterfaceLocal scope = 0x1
+	scopeLinkLocal      scope = 0x2
+	scopeAdminLocal     scope = 0x4
+	scopeSiteLocal      scope = 0x5
+	scopeOrgLocal       scope = 0x8
+	scopeGlobal         scope = 0xe
+)
+
+func classifyScope(ip IP) scope {
+	if ip.IsLoopback() || ip.IsLinkLocalUnicast() {
+		return scopeLinkLocal
+	}
+	ipv6 := len(ip) == IPv6len && ip.To4() == nil
+	if ipv6 && ip.IsMulticast() {
+		return scope(ip[1] & 0xf)
+	}
+	// Site-local addresses are defined in RFC 3513 section 2.5.6
+	// (and deprecated in RFC 3879).
+	if ipv6 && ip[0] == 0xfe && ip[1]&0xc0 == 0xc0 {
+		return scopeSiteLocal
+	}
+	return scopeGlobal
+}
+
+// commonPrefixLen reports the length of the longest prefix (looking
+// at the most significant, or leftmost, bits) that the
+// two addresses have in common, up to the length of a's prefix (i.e.,
+// the portion of the address not including the interface ID).
+//
+// If a or b is an IPv4 address as an IPv6 address, the IPv4 addresses
+// are compared (with max common prefix length of 32).
+// If a and b are different IP versions, 0 is returned.
+//
+// See https://tools.ietf.org/html/rfc6724#section-2.2
+func commonPrefixLen(a, b IP) (cpl int) {
+	if a4 := a.To4(); a4 != nil {
+		a = a4
+	}
+	if b4 := b.To4(); b4 != nil {
+		b = b4
+	}
+	if len(a) != len(b) {
+		return 0
+	}
+	// If IPv6, only up to the prefix (first 64 bits)
+	if len(a) > 8 {
+		a = a[:8]
+		b = b[:8]
+	}
+	for len(a) > 0 {
+		if a[0] == b[0] {
+			cpl += 8
+			a = a[1:]
+			b = b[1:]
+			continue
+		}
+		bits := 8
+		ab, bb := a[0], b[0]
+		for {
+			ab >>= 1
+			bb >>= 1
+			bits--
+			if ab == bb {
+				cpl += bits
+				return
+			}
+		}
+	}
+	return
+}
diff --git a/contrib/go/_std_1.18/src/net/cgo_bsd.go b/contrib/go/_std_1.19/src/net/cgo_bsd.go
index 1456289b06..1456289b06 100644
--- a/contrib/go/_std_1.18/src/net/cgo_bsd.go
+++ b/contrib/go/_std_1.19/src/net/cgo_bsd.go
diff --git a/contrib/go/_std_1.18/src/net/cgo_linux.go b/contrib/go/_std_1.19/src/net/cgo_linux.go
index de6e87f176..de6e87f176 100644
--- a/contrib/go/_std_1.18/src/net/cgo_linux.go
+++ b/contrib/go/_std_1.19/src/net/cgo_linux.go
diff --git a/contrib/go/_std_1.18/src/net/cgo_resnew.go b/contrib/go/_std_1.19/src/net/cgo_resnew.go
index fa6e68770c..fa6e68770c 100644
--- a/contrib/go/_std_1.18/src/net/cgo_resnew.go
+++ b/contrib/go/_std_1.19/src/net/cgo_resnew.go
diff --git a/contrib/go/_std_1.18/src/net/cgo_socknew.go b/contrib/go/_std_1.19/src/net/cgo_socknew.go
index fbb9e10f34..fbb9e10f34 100644
--- a/contrib/go/_std_1.18/src/net/cgo_socknew.go
+++ b/contrib/go/_std_1.19/src/net/cgo_socknew.go
diff --git a/contrib/go/_std_1.18/src/net/cgo_sockold.go b/contrib/go/_std_1.19/src/net/cgo_sockold.go
index 4d9869de04..4d9869de04 100644
--- a/contrib/go/_std_1.18/src/net/cgo_sockold.go
+++ b/contrib/go/_std_1.19/src/net/cgo_sockold.go
diff --git a/contrib/go/_std_1.19/src/net/cgo_unix.go b/contrib/go/_std_1.19/src/net/cgo_unix.go
new file mode 100644
index 0000000000..71d90560ac
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/cgo_unix.go
@@ -0,0 +1,348 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build cgo && !netgo && unix
+
+package net
+
+/*
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netdb.h>
+#include <unistd.h>
+#include <string.h>
+
+// If nothing else defined EAI_OVERFLOW, make sure it has a value.
+#ifndef EAI_OVERFLOW
+#define EAI_OVERFLOW -12
+#endif
+*/
+import "C"
+
+import (
+	"context"
+	"syscall"
+	"unsafe"
+)
+
+// An addrinfoErrno represents a getaddrinfo, getnameinfo-specific
+// error number. It's a signed number and a zero value is a non-error
+// by convention.
+type addrinfoErrno int
+
+func (eai addrinfoErrno) Error() string   { return C.GoString(C.gai_strerror(C.int(eai))) }
+func (eai addrinfoErrno) Temporary() bool { return eai == C.EAI_AGAIN }
+func (eai addrinfoErrno) Timeout() bool   { return false }
+
+type portLookupResult struct {
+	port int
+	err  error
+}
+
+type ipLookupResult struct {
+	addrs []IPAddr
+	cname string
+	err   error
+}
+
+type reverseLookupResult struct {
+	names []string
+	err   error
+}
+
+func cgoLookupHost(ctx context.Context, name string) (hosts []string, err error, completed bool) {
+	addrs, err, completed := cgoLookupIP(ctx, "ip", name)
+	for _, addr := range addrs {
+		hosts = append(hosts, addr.String())
+	}
+	return
+}
+
+func cgoLookupPort(ctx context.Context, network, service string) (port int, err error, completed bool) {
+	var hints C.struct_addrinfo
+	switch network {
+	case "": // no hints
+	case "tcp", "tcp4", "tcp6":
+		hints.ai_socktype = C.SOCK_STREAM
+		hints.ai_protocol = C.IPPROTO_TCP
+	case "udp", "udp4", "udp6":
+		hints.ai_socktype = C.SOCK_DGRAM
+		hints.ai_protocol = C.IPPROTO_UDP
+	default:
+		return 0, &DNSError{Err: "unknown network", Name: network + "/" + service}, true
+	}
+	switch ipVersion(network) {
+	case '4':
+		hints.ai_family = C.AF_INET
+	case '6':
+		hints.ai_family = C.AF_INET6
+	}
+	if ctx.Done() == nil {
+		port, err := cgoLookupServicePort(&hints, network, service)
+		return port, err, true
+	}
+	result := make(chan portLookupResult, 1)
+	go cgoPortLookup(result, &hints, network, service)
+	select {
+	case r := <-result:
+		return r.port, r.err, true
+	case <-ctx.Done():
+		// Since there isn't a portable way to cancel the lookup,
+		// we just let it finish and write to the buffered channel.
+		return 0, mapErr(ctx.Err()), false
+	}
+}
+
+func cgoLookupServicePort(hints *C.struct_addrinfo, network, service string) (port int, err error) {
+	cservice := make([]byte, len(service)+1)
+	copy(cservice, service)
+	// Lowercase the C service name.
+	for i, b := range cservice[:len(service)] {
+		cservice[i] = lowerASCII(b)
+	}
+	var res *C.struct_addrinfo
+	gerrno, err := C.getaddrinfo(nil, (*C.char)(unsafe.Pointer(&cservice[0])), hints, &res)
+	if gerrno != 0 {
+		isTemporary := false
+		switch gerrno {
+		case C.EAI_SYSTEM:
+			if err == nil { // see golang.org/issue/6232
+				err = syscall.EMFILE
+			}
+		default:
+			err = addrinfoErrno(gerrno)
+			isTemporary = addrinfoErrno(gerrno).Temporary()
+		}
+		return 0, &DNSError{Err: err.Error(), Name: network + "/" + service, IsTemporary: isTemporary}
+	}
+	defer C.freeaddrinfo(res)
+
+	for r := res; r != nil; r = r.ai_next {
+		switch r.ai_family {
+		case C.AF_INET:
+			sa := (*syscall.RawSockaddrInet4)(unsafe.Pointer(r.ai_addr))
+			p := (*[2]byte)(unsafe.Pointer(&sa.Port))
+			return int(p[0])<<8 | int(p[1]), nil
+		case C.AF_INET6:
+			sa := (*syscall.RawSockaddrInet6)(unsafe.Pointer(r.ai_addr))
+			p := (*[2]byte)(unsafe.Pointer(&sa.Port))
+			return int(p[0])<<8 | int(p[1]), nil
+		}
+	}
+	return 0, &DNSError{Err: "unknown port", Name: network + "/" + service}
+}
+
+func cgoPortLookup(result chan<- portLookupResult, hints *C.struct_addrinfo, network, service string) {
+	port, err := cgoLookupServicePort(hints, network, service)
+	result <- portLookupResult{port, err}
+}
+
+func cgoLookupIPCNAME(network, name string) (addrs []IPAddr, cname string, err error) {
+	acquireThread()
+	defer releaseThread()
+
+	var hints C.struct_addrinfo
+	hints.ai_flags = cgoAddrInfoFlags
+	hints.ai_socktype = C.SOCK_STREAM
+	hints.ai_family = C.AF_UNSPEC
+	switch ipVersion(network) {
+	case '4':
+		hints.ai_family = C.AF_INET
+	case '6':
+		hints.ai_family = C.AF_INET6
+	}
+
+	h := make([]byte, len(name)+1)
+	copy(h, name)
+	var res *C.struct_addrinfo
+	gerrno, err := C.getaddrinfo((*C.char)(unsafe.Pointer(&h[0])), nil, &hints, &res)
+	if gerrno != 0 {
+		isErrorNoSuchHost := false
+		isTemporary := false
+		switch gerrno {
+		case C.EAI_SYSTEM:
+			if err == nil {
+				// err should not be nil, but sometimes getaddrinfo returns
+				// gerrno == C.EAI_SYSTEM with err == nil on Linux.
+				// The report claims that it happens when we have too many
+				// open files, so use syscall.EMFILE (too many open files in system).
+				// Most system calls would return ENFILE (too many open files),
+				// so at the least EMFILE should be easy to recognize if this
+				// comes up again. golang.org/issue/6232.
+				err = syscall.EMFILE
+			}
+		case C.EAI_NONAME:
+			err = errNoSuchHost
+			isErrorNoSuchHost = true
+		default:
+			err = addrinfoErrno(gerrno)
+			isTemporary = addrinfoErrno(gerrno).Temporary()
+		}
+
+		return nil, "", &DNSError{Err: err.Error(), Name: name, IsNotFound: isErrorNoSuchHost, IsTemporary: isTemporary}
+	}
+	defer C.freeaddrinfo(res)
+
+	if res != nil {
+		cname = C.GoString(res.ai_canonname)
+		if cname == "" {
+			cname = name
+		}
+		if len(cname) > 0 && cname[len(cname)-1] != '.' {
+			cname += "."
+		}
+	}
+	for r := res; r != nil; r = r.ai_next {
+		// We only asked for SOCK_STREAM, but check anyhow.
+		if r.ai_socktype != C.SOCK_STREAM {
+			continue
+		}
+		switch r.ai_family {
+		case C.AF_INET:
+			sa := (*syscall.RawSockaddrInet4)(unsafe.Pointer(r.ai_addr))
+			addr := IPAddr{IP: copyIP(sa.Addr[:])}
+			addrs = append(addrs, addr)
+		case C.AF_INET6:
+			sa := (*syscall.RawSockaddrInet6)(unsafe.Pointer(r.ai_addr))
+			addr := IPAddr{IP: copyIP(sa.Addr[:]), Zone: zoneCache.name(int(sa.Scope_id))}
+			addrs = append(addrs, addr)
+		}
+	}
+	return addrs, cname, nil
+}
+
+func cgoIPLookup(result chan<- ipLookupResult, network, name string) {
+	addrs, cname, err := cgoLookupIPCNAME(network, name)
+	result <- ipLookupResult{addrs, cname, err}
+}
+
+func cgoLookupIP(ctx context.Context, network, name string) (addrs []IPAddr, err error, completed bool) {
+	if ctx.Done() == nil {
+		addrs, _, err = cgoLookupIPCNAME(network, name)
+		return addrs, err, true
+	}
+	result := make(chan ipLookupResult, 1)
+	go cgoIPLookup(result, network, name)
+	select {
+	case r := <-result:
+		return r.addrs, r.err, true
+	case <-ctx.Done():
+		return nil, mapErr(ctx.Err()), false
+	}
+}
+
+func cgoLookupCNAME(ctx context.Context, name string) (cname string, err error, completed bool) {
+	if ctx.Done() == nil {
+		_, cname, err = cgoLookupIPCNAME("ip", name)
+		return cname, err, true
+	}
+	result := make(chan ipLookupResult, 1)
+	go cgoIPLookup(result, "ip", name)
+	select {
+	case r := <-result:
+		return r.cname, r.err, true
+	case <-ctx.Done():
+		return "", mapErr(ctx.Err()), false
+	}
+}
+
+// These are roughly enough for the following:
+//
+//	 Source		Encoding			Maximum length of single name entry
+//	 Unicast DNS		ASCII or			<=253 + a NUL terminator
+//				Unicode in RFC 5892		252 * total number of labels + delimiters + a NUL terminator
+//	 Multicast DNS	UTF-8 in RFC 5198 or		<=253 + a NUL terminator
+//				the same as unicast DNS ASCII	<=253 + a NUL terminator
+//	 Local database	various				depends on implementation
+const (
+	nameinfoLen    = 64
+	maxNameinfoLen = 4096
+)
+
+func cgoLookupPTR(ctx context.Context, addr string) (names []string, err error, completed bool) {
+	var zone string
+	ip := parseIPv4(addr)
+	if ip == nil {
+		ip, zone = parseIPv6Zone(addr)
+	}
+	if ip == nil {
+		return nil, &DNSError{Err: "invalid address", Name: addr}, true
+	}
+	sa, salen := cgoSockaddr(ip, zone)
+	if sa == nil {
+		return nil, &DNSError{Err: "invalid address " + ip.String(), Name: addr}, true
+	}
+	if ctx.Done() == nil {
+		names, err := cgoLookupAddrPTR(addr, sa, salen)
+		return names, err, true
+	}
+	result := make(chan reverseLookupResult, 1)
+	go cgoReverseLookup(result, addr, sa, salen)
+	select {
+	case r := <-result:
+		return r.names, r.err, true
+	case <-ctx.Done():
+		return nil, mapErr(ctx.Err()), false
+	}
+}
+
+func cgoLookupAddrPTR(addr string, sa *C.struct_sockaddr, salen C.socklen_t) (names []string, err error) {
+	acquireThread()
+	defer releaseThread()
+
+	var gerrno int
+	var b []byte
+	for l := nameinfoLen; l <= maxNameinfoLen; l *= 2 {
+		b = make([]byte, l)
+		gerrno, err = cgoNameinfoPTR(b, sa, salen)
+		if gerrno == 0 || gerrno != C.EAI_OVERFLOW {
+			break
+		}
+	}
+	if gerrno != 0 {
+		isTemporary := false
+		switch gerrno {
+		case C.EAI_SYSTEM:
+			if err == nil { // see golang.org/issue/6232
+				err = syscall.EMFILE
+			}
+		default:
+			err = addrinfoErrno(gerrno)
+			isTemporary = addrinfoErrno(gerrno).Temporary()
+		}
+		return nil, &DNSError{Err: err.Error(), Name: addr, IsTemporary: isTemporary}
+	}
+	for i := 0; i < len(b); i++ {
+		if b[i] == 0 {
+			b = b[:i]
+			break
+		}
+	}
+	return []string{absDomainName(string(b))}, nil
+}
+
+func cgoReverseLookup(result chan<- reverseLookupResult, addr string, sa *C.struct_sockaddr, salen C.socklen_t) {
+	names, err := cgoLookupAddrPTR(addr, sa, salen)
+	result <- reverseLookupResult{names, err}
+}
+
+func cgoSockaddr(ip IP, zone string) (*C.struct_sockaddr, C.socklen_t) {
+	if ip4 := ip.To4(); ip4 != nil {
+		return cgoSockaddrInet4(ip4), C.socklen_t(syscall.SizeofSockaddrInet4)
+	}
+	if ip6 := ip.To16(); ip6 != nil {
+		return cgoSockaddrInet6(ip6, zoneCache.index(zone)), C.socklen_t(syscall.SizeofSockaddrInet6)
+	}
+	return nil, 0
+}
+
+func copyIP(x IP) IP {
+	if len(x) < 16 {
+		return x.To16()
+	}
+	y := make(IP, len(x))
+	copy(y, x)
+	return y
+}
diff --git a/contrib/go/_std_1.19/src/net/conf.go b/contrib/go/_std_1.19/src/net/conf.go
new file mode 100644
index 0000000000..b08bbc7d7a
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/conf.go
@@ -0,0 +1,352 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !js
+
+package net
+
+import (
+	"internal/bytealg"
+	"internal/godebug"
+	"os"
+	"runtime"
+	"sync"
+	"syscall"
+)
+
+// conf represents a system's network configuration.
+type conf struct {
+	// forceCgoLookupHost forces CGO to always be used, if available.
+	forceCgoLookupHost bool
+
+	netGo  bool // go DNS resolution forced
+	netCgo bool // non-go DNS resolution forced (cgo, or win32)
+
+	// machine has an /etc/mdns.allow file
+	hasMDNSAllow bool
+
+	goos          string // the runtime.GOOS, to ease testing
+	dnsDebugLevel int
+
+	nss    *nssConf
+	resolv *dnsConfig
+}
+
+var (
+	confOnce sync.Once // guards init of confVal via initConfVal
+	confVal  = &conf{goos: runtime.GOOS}
+)
+
+// systemConf returns the machine's network configuration.
+func systemConf() *conf {
+	confOnce.Do(initConfVal)
+	return confVal
+}
+
+func initConfVal() {
+	dnsMode, debugLevel := goDebugNetDNS()
+	confVal.dnsDebugLevel = debugLevel
+	confVal.netGo = netGo || dnsMode == "go"
+	confVal.netCgo = netCgo || dnsMode == "cgo"
+	if !confVal.netGo && !confVal.netCgo && (runtime.GOOS == "windows" || runtime.GOOS == "plan9") {
+		// Neither of these platforms actually use cgo.
+		//
+		// The meaning of "cgo" mode in the net package is
+		// really "the native OS way", which for libc meant
+		// cgo on the original platforms that motivated
+		// PreferGo support before Windows and Plan9 got support,
+		// at which time the GODEBUG=netdns=go and GODEBUG=netdns=cgo
+		// names were already kinda locked in.
+		confVal.netCgo = true
+	}
+
+	if confVal.dnsDebugLevel > 0 {
+		defer func() {
+			if confVal.dnsDebugLevel > 1 {
+				println("go package net: confVal.netCgo =", confVal.netCgo, " netGo =", confVal.netGo)
+			}
+			switch {
+			case confVal.netGo:
+				if netGo {
+					println("go package net: built with netgo build tag; using Go's DNS resolver")
+				} else {
+					println("go package net: GODEBUG setting forcing use of Go's resolver")
+				}
+			case confVal.forceCgoLookupHost:
+				println("go package net: using cgo DNS resolver")
+			default:
+				println("go package net: dynamic selection of DNS resolver")
+			}
+		}()
+	}
+
+	// Darwin pops up annoying dialog boxes if programs try to do
+	// their own DNS requests. So always use cgo instead, which
+	// avoids that.
+	if runtime.GOOS == "darwin" || runtime.GOOS == "ios" {
+		confVal.forceCgoLookupHost = true
+		return
+	}
+
+	if runtime.GOOS == "windows" || runtime.GOOS == "plan9" {
+		return
+	}
+
+	// If any environment-specified resolver options are specified,
+	// force cgo. Note that LOCALDOMAIN can change behavior merely
+	// by being specified with the empty string.
+	_, localDomainDefined := syscall.Getenv("LOCALDOMAIN")
+	if os.Getenv("RES_OPTIONS") != "" ||
+		os.Getenv("HOSTALIASES") != "" ||
+		confVal.netCgo ||
+		localDomainDefined {
+		confVal.forceCgoLookupHost = true
+		return
+	}
+
+	// OpenBSD apparently lets you override the location of resolv.conf
+	// with ASR_CONFIG. If we notice that, defer to libc.
+	if runtime.GOOS == "openbsd" && os.Getenv("ASR_CONFIG") != "" {
+		confVal.forceCgoLookupHost = true
+		return
+	}
+
+	if runtime.GOOS != "openbsd" {
+		confVal.nss = parseNSSConfFile("/etc/nsswitch.conf")
+	}
+
+	confVal.resolv = dnsReadConfig("/etc/resolv.conf")
+	if confVal.resolv.err != nil && !os.IsNotExist(confVal.resolv.err) &&
+		!os.IsPermission(confVal.resolv.err) {
+		// If we can't read the resolv.conf file, assume it
+		// had something important in it and defer to cgo.
+		// libc's resolver might then fail too, but at least
+		// it wasn't our fault.
+		confVal.forceCgoLookupHost = true
+	}
+
+	if _, err := os.Stat("/etc/mdns.allow"); err == nil {
+		confVal.hasMDNSAllow = true
+	}
+}
+
+// canUseCgo reports whether calling cgo functions is allowed
+// for non-hostname lookups.
+func (c *conf) canUseCgo() bool {
+	return c.hostLookupOrder(nil, "") == hostLookupCgo
+}
+
+// hostLookupOrder determines which strategy to use to resolve hostname.
+// The provided Resolver is optional. nil means to not consider its options.
+func (c *conf) hostLookupOrder(r *Resolver, hostname string) (ret hostLookupOrder) {
+	if c.dnsDebugLevel > 1 {
+		defer func() {
+			print("go package net: hostLookupOrder(", hostname, ") = ", ret.String(), "\n")
+		}()
+	}
+	fallbackOrder := hostLookupCgo
+	if c.netGo || r.preferGo() {
+		switch c.goos {
+		case "windows":
+			// TODO(bradfitz): implement files-based
+			// lookup on Windows too? I guess /etc/hosts
+			// kinda exists on Windows. But for now, only
+			// do DNS.
+			fallbackOrder = hostLookupDNS
+		default:
+			fallbackOrder = hostLookupFilesDNS
+		}
+	}
+	if c.goos == "windows" || c.goos == "plan9" {
+		return fallbackOrder
+	}
+	if c.forceCgoLookupHost || c.resolv.unknownOpt || c.goos == "android" {
+		return fallbackOrder
+	}
+	if bytealg.IndexByteString(hostname, '\\') != -1 || bytealg.IndexByteString(hostname, '%') != -1 {
+		// Don't deal with special form hostnames with backslashes
+		// or '%'.
+		return fallbackOrder
+	}
+
+	// OpenBSD is unique and doesn't use nsswitch.conf.
+	// It also doesn't support mDNS.
+	if c.goos == "openbsd" {
+		// OpenBSD's resolv.conf manpage says that a non-existent
+		// resolv.conf means "lookup" defaults to only "files",
+		// without DNS lookups.
+		if os.IsNotExist(c.resolv.err) {
+			return hostLookupFiles
+		}
+		lookup := c.resolv.lookup
+		if len(lookup) == 0 {
+			// https://www.openbsd.org/cgi-bin/man.cgi/OpenBSD-current/man5/resolv.conf.5
+			// "If the lookup keyword is not used in the
+			// system's resolv.conf file then the assumed
+			// order is 'bind file'"
+			return hostLookupDNSFiles
+		}
+		if len(lookup) < 1 || len(lookup) > 2 {
+			return fallbackOrder
+		}
+		switch lookup[0] {
+		case "bind":
+			if len(lookup) == 2 {
+				if lookup[1] == "file" {
+					return hostLookupDNSFiles
+				}
+				return fallbackOrder
+			}
+			return hostLookupDNS
+		case "file":
+			if len(lookup) == 2 {
+				if lookup[1] == "bind" {
+					return hostLookupFilesDNS
+				}
+				return fallbackOrder
+			}
+			return hostLookupFiles
+		default:
+			return fallbackOrder
+		}
+	}
+
+	// Canonicalize the hostname by removing any trailing dot.
+	if stringsHasSuffix(hostname, ".") {
+		hostname = hostname[:len(hostname)-1]
+	}
+	if stringsHasSuffixFold(hostname, ".local") {
+		// Per RFC 6762, the ".local" TLD is special. And
+		// because Go's native resolver doesn't do mDNS or
+		// similar local resolution mechanisms, assume that
+		// libc might (via Avahi, etc) and use cgo.
+		return fallbackOrder
+	}
+
+	nss := c.nss
+	srcs := nss.sources["hosts"]
+	// If /etc/nsswitch.conf doesn't exist or doesn't specify any
+	// sources for "hosts", assume Go's DNS will work fine.
+	if os.IsNotExist(nss.err) || (nss.err == nil && len(srcs) == 0) {
+		if c.goos == "solaris" {
+			// illumos defaults to "nis [NOTFOUND=return] files"
+			return fallbackOrder
+		}
+		return hostLookupFilesDNS
+	}
+	if nss.err != nil {
+		// We failed to parse or open nsswitch.conf, so
+		// conservatively assume we should use cgo if it's
+		// available.
+		return fallbackOrder
+	}
+
+	var mdnsSource, filesSource, dnsSource bool
+	var first string
+	for _, src := range srcs {
+		if src.source == "myhostname" {
+			if isLocalhost(hostname) || isGateway(hostname) {
+				return fallbackOrder
+			}
+			hn, err := getHostname()
+			if err != nil || stringsEqualFold(hostname, hn) {
+				return fallbackOrder
+			}
+			continue
+		}
+		if src.source == "files" || src.source == "dns" {
+			if !src.standardCriteria() {
+				return fallbackOrder // non-standard; let libc deal with it.
+			}
+			if src.source == "files" {
+				filesSource = true
+			} else if src.source == "dns" {
+				dnsSource = true
+			}
+			if first == "" {
+				first = src.source
+			}
+			continue
+		}
+		if stringsHasPrefix(src.source, "mdns") {
+			// e.g. "mdns4", "mdns4_minimal"
+			// We already returned true before if it was *.local.
+			// libc wouldn't have found a hit on this anyway.
+			mdnsSource = true
+			continue
+		}
+		// Some source we don't know how to deal with.
+		return fallbackOrder
+	}
+
+	// We don't parse mdns.allow files. They're rare. If one
+	// exists, it might list other TLDs (besides .local) or even
+	// '*', so just let libc deal with it.
+	if mdnsSource && c.hasMDNSAllow {
+		return fallbackOrder
+	}
+
+	// Cases where Go can handle it without cgo and C thread
+	// overhead.
+	switch {
+	case filesSource && dnsSource:
+		if first == "files" {
+			return hostLookupFilesDNS
+		} else {
+			return hostLookupDNSFiles
+		}
+	case filesSource:
+		return hostLookupFiles
+	case dnsSource:
+		return hostLookupDNS
+	}
+
+	// Something weird. Let libc deal with it.
+	return fallbackOrder
+}
+
+// goDebugNetDNS parses the value of the GODEBUG "netdns" value.
+// The netdns value can be of the form:
+//
+//	1       // debug level 1
+//	2       // debug level 2
+//	cgo     // use cgo for DNS lookups
+//	go      // use go for DNS lookups
+//	cgo+1   // use cgo for DNS lookups + debug level 1
+//	1+cgo   // same
+//	cgo+2   // same, but debug level 2
+//
+// etc.
+func goDebugNetDNS() (dnsMode string, debugLevel int) {
+	goDebug := godebug.Get("netdns")
+	parsePart := func(s string) {
+		if s == "" {
+			return
+		}
+		if '0' <= s[0] && s[0] <= '9' {
+			debugLevel, _, _ = dtoi(s)
+		} else {
+			dnsMode = s
+		}
+	}
+	if i := bytealg.IndexByteString(goDebug, '+'); i != -1 {
+		parsePart(goDebug[:i])
+		parsePart(goDebug[i+1:])
+		return
+	}
+	parsePart(goDebug)
+	return
+}
+
+// isLocalhost reports whether h should be considered a "localhost"
+// name for the myhostname NSS module.
+func isLocalhost(h string) bool {
+	return stringsEqualFold(h, "localhost") || stringsEqualFold(h, "localhost.localdomain") || stringsHasSuffixFold(h, ".localhost") || stringsHasSuffixFold(h, ".localhost.localdomain")
+}
+
+// isGateway reports whether h should be considered a "gateway"
+// name for the myhostname NSS module.
+func isGateway(h string) bool {
+	return stringsEqualFold(h, "gateway")
+}
diff --git a/contrib/go/_std_1.19/src/net/dial.go b/contrib/go/_std_1.19/src/net/dial.go
new file mode 100644
index 0000000000..c538342566
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/dial.go
@@ -0,0 +1,742 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+	"context"
+	"internal/nettrace"
+	"syscall"
+	"time"
+)
+
+// defaultTCPKeepAlive is a default constant value for TCPKeepAlive times
+// See golang.org/issue/31510
+const (
+	defaultTCPKeepAlive = 15 * time.Second
+)
+
+// A Dialer contains options for connecting to an address.
+//
+// The zero value for each field is equivalent to dialing
+// without that option. Dialing with the zero value of Dialer
+// is therefore equivalent to just calling the Dial function.
+//
+// It is safe to call Dialer's methods concurrently.
+type Dialer struct {
+	// Timeout is the maximum amount of time a dial will wait for
+	// a connect to complete. If Deadline is also set, it may fail
+	// earlier.
+	//
+	// The default is no timeout.
+	//
+	// When using TCP and dialing a host name with multiple IP
+	// addresses, the timeout may be divided between them.
+	//
+	// With or without a timeout, the operating system may impose
+	// its own earlier timeout. For instance, TCP timeouts are
+	// often around 3 minutes.
+	Timeout time.Duration
+
+	// Deadline is the absolute point in time after which dials
+	// will fail. If Timeout is set, it may fail earlier.
+	// Zero means no deadline, or dependent on the operating system
+	// as with the Timeout option.
+	Deadline time.Time
+
+	// LocalAddr is the local address to use when dialing an
+	// address. The address must be of a compatible type for the
+	// network being dialed.
+	// If nil, a local address is automatically chosen.
+	LocalAddr Addr
+
+	// DualStack previously enabled RFC 6555 Fast Fallback
+	// support, also known as "Happy Eyeballs", in which IPv4 is
+	// tried soon if IPv6 appears to be misconfigured and
+	// hanging.
+	//
+	// Deprecated: Fast Fallback is enabled by default. To
+	// disable, set FallbackDelay to a negative value.
+	DualStack bool
+
+	// FallbackDelay specifies the length of time to wait before
+	// spawning a RFC 6555 Fast Fallback connection. That is, this
+	// is the amount of time to wait for IPv6 to succeed before
+	// assuming that IPv6 is misconfigured and falling back to
+	// IPv4.
+	//
+	// If zero, a default delay of 300ms is used.
+	// A negative value disables Fast Fallback support.
+	FallbackDelay time.Duration
+
+	// KeepAlive specifies the interval between keep-alive
+	// probes for an active network connection.
+	// If zero, keep-alive probes are sent with a default value
+	// (currently 15 seconds), if supported by the protocol and operating
+	// system. Network protocols or operating systems that do
+	// not support keep-alives ignore this field.
+	// If negative, keep-alive probes are disabled.
+	KeepAlive time.Duration
+
+	// Resolver optionally specifies an alternate resolver to use.
+	Resolver *Resolver
+
+	// Cancel is an optional channel whose closure indicates that
+	// the dial should be canceled. Not all types of dials support
+	// cancellation.
+	//
+	// Deprecated: Use DialContext instead.
+	Cancel <-chan struct{}
+
+	// If Control is not nil, it is called after creating the network
+	// connection but before actually dialing.
+	//
+	// Network and address parameters passed to Control method are not
+	// necessarily the ones passed to Dial. For example, passing "tcp" to Dial
+	// will cause the Control function to be called with "tcp4" or "tcp6".
+	Control func(network, address string, c syscall.RawConn) error
+}
+
+func (d *Dialer) dualStack() bool { return d.FallbackDelay >= 0 }
+
+func minNonzeroTime(a, b time.Time) time.Time {
+	if a.IsZero() {
+		return b
+	}
+	if b.IsZero() || a.Before(b) {
+		return a
+	}
+	return b
+}
+
+// deadline returns the earliest of:
+//   - now+Timeout
+//   - d.Deadline
+//   - the context's deadline
+//
+// Or zero, if none of Timeout, Deadline, or context's deadline is set.
+func (d *Dialer) deadline(ctx context.Context, now time.Time) (earliest time.Time) {
+	if d.Timeout != 0 { // including negative, for historical reasons
+		earliest = now.Add(d.Timeout)
+	}
+	if d, ok := ctx.Deadline(); ok {
+		earliest = minNonzeroTime(earliest, d)
+	}
+	return minNonzeroTime(earliest, d.Deadline)
+}
+
+func (d *Dialer) resolver() *Resolver {
+	if d.Resolver != nil {
+		return d.Resolver
+	}
+	return DefaultResolver
+}
+
+// partialDeadline returns the deadline to use for a single address,
+// when multiple addresses are pending.
+func partialDeadline(now, deadline time.Time, addrsRemaining int) (time.Time, error) {
+	if deadline.IsZero() {
+		return deadline, nil
+	}
+	timeRemaining := deadline.Sub(now)
+	if timeRemaining <= 0 {
+		return time.Time{}, errTimeout
+	}
+	// Tentatively allocate equal time to each remaining address.
+	timeout := timeRemaining / time.Duration(addrsRemaining)
+	// If the time per address is too short, steal from the end of the list.
+	const saneMinimum = 2 * time.Second
+	if timeout < saneMinimum {
+		if timeRemaining < saneMinimum {
+			timeout = timeRemaining
+		} else {
+			timeout = saneMinimum
+		}
+	}
+	return now.Add(timeout), nil
+}
+
+func (d *Dialer) fallbackDelay() time.Duration {
+	if d.FallbackDelay > 0 {
+		return d.FallbackDelay
+	} else {
+		return 300 * time.Millisecond
+	}
+}
+
+func parseNetwork(ctx context.Context, network string, needsProto bool) (afnet string, proto int, err error) {
+	i := last(network, ':')
+	if i < 0 { // no colon
+		switch network {
+		case "tcp", "tcp4", "tcp6":
+		case "udp", "udp4", "udp6":
+		case "ip", "ip4", "ip6":
+			if needsProto {
+				return "", 0, UnknownNetworkError(network)
+			}
+		case "unix", "unixgram", "unixpacket":
+		default:
+			return "", 0, UnknownNetworkError(network)
+		}
+		return network, 0, nil
+	}
+	afnet = network[:i]
+	switch afnet {
+	case "ip", "ip4", "ip6":
+		protostr := network[i+1:]
+		proto, i, ok := dtoi(protostr)
+		if !ok || i != len(protostr) {
+			proto, err = lookupProtocol(ctx, protostr)
+			if err != nil {
+				return "", 0, err
+			}
+		}
+		return afnet, proto, nil
+	}
+	return "", 0, UnknownNetworkError(network)
+}
+
+// resolveAddrList resolves addr using hint and returns a list of
+// addresses. The result contains at least one address when error is
+// nil.
+func (r *Resolver) resolveAddrList(ctx context.Context, op, network, addr string, hint Addr) (addrList, error) {
+	afnet, _, err := parseNetwork(ctx, network, true)
+	if err != nil {
+		return nil, err
+	}
+	if op == "dial" && addr == "" {
+		return nil, errMissingAddress
+	}
+	switch afnet {
+	case "unix", "unixgram", "unixpacket":
+		addr, err := ResolveUnixAddr(afnet, addr)
+		if err != nil {
+			return nil, err
+		}
+		if op == "dial" && hint != nil && addr.Network() != hint.Network() {
+			return nil, &AddrError{Err: "mismatched local address type", Addr: hint.String()}
+		}
+		return addrList{addr}, nil
+	}
+	addrs, err := r.internetAddrList(ctx, afnet, addr)
+	if err != nil || op != "dial" || hint == nil {
+		return addrs, err
+	}
+	var (
+		tcp      *TCPAddr
+		udp      *UDPAddr
+		ip       *IPAddr
+		wildcard bool
+	)
+	switch hint := hint.(type) {
+	case *TCPAddr:
+		tcp = hint
+		wildcard = tcp.isWildcard()
+	case *UDPAddr:
+		udp = hint
+		wildcard = udp.isWildcard()
+	case *IPAddr:
+		ip = hint
+		wildcard = ip.isWildcard()
+	}
+	naddrs := addrs[:0]
+	for _, addr := range addrs {
+		if addr.Network() != hint.Network() {
+			return nil, &AddrError{Err: "mismatched local address type", Addr: hint.String()}
+		}
+		switch addr := addr.(type) {
+		case *TCPAddr:
+			if !wildcard && !addr.isWildcard() && !addr.IP.matchAddrFamily(tcp.IP) {
+				continue
+			}
+			naddrs = append(naddrs, addr)
+		case *UDPAddr:
+			if !wildcard && !addr.isWildcard() && !addr.IP.matchAddrFamily(udp.IP) {
+				continue
+			}
+			naddrs = append(naddrs, addr)
+		case *IPAddr:
+			if !wildcard && !addr.isWildcard() && !addr.IP.matchAddrFamily(ip.IP) {
+				continue
+			}
+			naddrs = append(naddrs, addr)
+		}
+	}
+	if len(naddrs) == 0 {
+		return nil, &AddrError{Err: errNoSuitableAddress.Error(), Addr: hint.String()}
+	}
+	return naddrs, nil
+}
+
+// Dial connects to the address on the named network.
+//
+// Known networks are "tcp", "tcp4" (IPv4-only), "tcp6" (IPv6-only),
+// "udp", "udp4" (IPv4-only), "udp6" (IPv6-only), "ip", "ip4"
+// (IPv4-only), "ip6" (IPv6-only), "unix", "unixgram" and
+// "unixpacket".
+//
+// For TCP and UDP networks, the address has the form "host:port".
+// The host must be a literal IP address, or a host name that can be
+// resolved to IP addresses.
+// The port must be a literal port number or a service name.
+// If the host is a literal IPv6 address it must be enclosed in square
+// brackets, as in "[2001:db8::1]:80" or "[fe80::1%zone]:80".
+// The zone specifies the scope of the literal IPv6 address as defined
+// in RFC 4007.
+// The functions JoinHostPort and SplitHostPort manipulate a pair of
+// host and port in this form.
+// When using TCP, and the host resolves to multiple IP addresses,
+// Dial will try each IP address in order until one succeeds.
+//
+// Examples:
+//
+//	Dial("tcp", "golang.org:http")
+//	Dial("tcp", "192.0.2.1:http")
+//	Dial("tcp", "198.51.100.1:80")
+//	Dial("udp", "[2001:db8::1]:domain")
+//	Dial("udp", "[fe80::1%lo0]:53")
+//	Dial("tcp", ":80")
+//
+// For IP networks, the network must be "ip", "ip4" or "ip6" followed
+// by a colon and a literal protocol number or a protocol name, and
+// the address has the form "host". The host must be a literal IP
+// address or a literal IPv6 address with zone.
+// It depends on each operating system how the operating system
+// behaves with a non-well known protocol number such as "0" or "255".
+//
+// Examples:
+//
+//	Dial("ip4:1", "192.0.2.1")
+//	Dial("ip6:ipv6-icmp", "2001:db8::1")
+//	Dial("ip6:58", "fe80::1%lo0")
+//
+// For TCP, UDP and IP networks, if the host is empty or a literal
+// unspecified IP address, as in ":80", "0.0.0.0:80" or "[::]:80" for
+// TCP and UDP, "", "0.0.0.0" or "::" for IP, the local system is
+// assumed.
+//
+// For Unix networks, the address must be a file system path.
+func Dial(network, address string) (Conn, error) {
+	var d Dialer
+	return d.Dial(network, address)
+}
+
+// DialTimeout acts like Dial but takes a timeout.
+//
+// The timeout includes name resolution, if required.
+// When using TCP, and the host in the address parameter resolves to
+// multiple IP addresses, the timeout is spread over each consecutive
+// dial, such that each is given an appropriate fraction of the time
+// to connect.
+//
+// See func Dial for a description of the network and address
+// parameters.
+func DialTimeout(network, address string, timeout time.Duration) (Conn, error) {
+	d := Dialer{Timeout: timeout}
+	return d.Dial(network, address)
+}
+
+// sysDialer contains a Dial's parameters and configuration.
+type sysDialer struct {
+	Dialer
+	network, address string
+	testHookDialTCP  func(ctx context.Context, net string, laddr, raddr *TCPAddr) (*TCPConn, error)
+}
+
+// Dial connects to the address on the named network.
+//
+// See func Dial for a description of the network and address
+// parameters.
+//
+// Dial uses context.Background internally; to specify the context, use
+// DialContext.
+func (d *Dialer) Dial(network, address string) (Conn, error) {
+	return d.DialContext(context.Background(), network, address)
+}
+
+// DialContext connects to the address on the named network using
+// the provided context.
+//
+// The provided Context must be non-nil. If the context expires before
+// the connection is complete, an error is returned. Once successfully
+// connected, any expiration of the context will not affect the
+// connection.
+//
+// When using TCP, and the host in the address parameter resolves to multiple
+// network addresses, any dial timeout (from d.Timeout or ctx) is spread
+// over each consecutive dial, such that each is given an appropriate
+// fraction of the time to connect.
+// For example, if a host has 4 IP addresses and the timeout is 1 minute,
+// the connect to each single address will be given 15 seconds to complete
+// before trying the next one.
+//
+// See func Dial for a description of the network and address
+// parameters.
+func (d *Dialer) DialContext(ctx context.Context, network, address string) (Conn, error) {
+	if ctx == nil {
+		panic("nil context")
+	}
+	deadline := d.deadline(ctx, time.Now())
+	if !deadline.IsZero() {
+		if d, ok := ctx.Deadline(); !ok || deadline.Before(d) {
+			subCtx, cancel := context.WithDeadline(ctx, deadline)
+			defer cancel()
+			ctx = subCtx
+		}
+	}
+	if oldCancel := d.Cancel; oldCancel != nil {
+		subCtx, cancel := context.WithCancel(ctx)
+		defer cancel()
+		go func() {
+			select {
+			case <-oldCancel:
+				cancel()
+			case <-subCtx.Done():
+			}
+		}()
+		ctx = subCtx
+	}
+
+	// Shadow the nettrace (if any) during resolve so Connect events don't fire for DNS lookups.
+	resolveCtx := ctx
+	if trace, _ := ctx.Value(nettrace.TraceKey{}).(*nettrace.Trace); trace != nil {
+		shadow := *trace
+		shadow.ConnectStart = nil
+		shadow.ConnectDone = nil
+		resolveCtx = context.WithValue(resolveCtx, nettrace.TraceKey{}, &shadow)
+	}
+
+	addrs, err := d.resolver().resolveAddrList(resolveCtx, "dial", network, address, d.LocalAddr)
+	if err != nil {
+		return nil, &OpError{Op: "dial", Net: network, Source: nil, Addr: nil, Err: err}
+	}
+
+	sd := &sysDialer{
+		Dialer:  *d,
+		network: network,
+		address: address,
+	}
+
+	var primaries, fallbacks addrList
+	if d.dualStack() && network == "tcp" {
+		primaries, fallbacks = addrs.partition(isIPv4)
+	} else {
+		primaries = addrs
+	}
+
+	c, err := sd.dialParallel(ctx, primaries, fallbacks)
+	if err != nil {
+		return nil, err
+	}
+
+	if tc, ok := c.(*TCPConn); ok && d.KeepAlive >= 0 {
+		setKeepAlive(tc.fd, true)
+		ka := d.KeepAlive
+		if d.KeepAlive == 0 {
+			ka = defaultTCPKeepAlive
+		}
+		setKeepAlivePeriod(tc.fd, ka)
+		testHookSetKeepAlive(ka)
+	}
+	return c, nil
+}
+
+// dialParallel races two copies of dialSerial, giving the first a
+// head start. It returns the first established connection and
+// closes the others. Otherwise it returns an error from the first
+// primary address.
+func (sd *sysDialer) dialParallel(ctx context.Context, primaries, fallbacks addrList) (Conn, error) {
+	if len(fallbacks) == 0 {
+		return sd.dialSerial(ctx, primaries)
+	}
+
+	returned := make(chan struct{})
+	defer close(returned)
+
+	type dialResult struct {
+		Conn
+		error
+		primary bool
+		done    bool
+	}
+	results := make(chan dialResult) // unbuffered
+
+	startRacer := func(ctx context.Context, primary bool) {
+		ras := primaries
+		if !primary {
+			ras = fallbacks
+		}
+		c, err := sd.dialSerial(ctx, ras)
+		select {
+		case results <- dialResult{Conn: c, error: err, primary: primary, done: true}:
+		case <-returned:
+			if c != nil {
+				c.Close()
+			}
+		}
+	}
+
+	var primary, fallback dialResult
+
+	// Start the main racer.
+	primaryCtx, primaryCancel := context.WithCancel(ctx)
+	defer primaryCancel()
+	go startRacer(primaryCtx, true)
+
+	// Start the timer for the fallback racer.
+	fallbackTimer := time.NewTimer(sd.fallbackDelay())
+	defer fallbackTimer.Stop()
+
+	for {
+		select {
+		case <-fallbackTimer.C:
+			fallbackCtx, fallbackCancel := context.WithCancel(ctx)
+			defer fallbackCancel()
+			go startRacer(fallbackCtx, false)
+
+		case res := <-results:
+			if res.error == nil {
+				return res.Conn, nil
+			}
+			if res.primary {
+				primary = res
+			} else {
+				fallback = res
+			}
+			if primary.done && fallback.done {
+				return nil, primary.error
+			}
+			if res.primary && fallbackTimer.Stop() {
+				// If we were able to stop the timer, that means it
+				// was running (hadn't yet started the fallback), but
+				// we just got an error on the primary path, so start
+				// the fallback immediately (in 0 nanoseconds).
+				fallbackTimer.Reset(0)
+			}
+		}
+	}
+}
+
+// dialSerial connects to a list of addresses in sequence, returning
+// either the first successful connection, or the first error.
+func (sd *sysDialer) dialSerial(ctx context.Context, ras addrList) (Conn, error) {
+	var firstErr error // The error from the first address is most relevant.
+
+	for i, ra := range ras {
+		select {
+		case <-ctx.Done():
+			return nil, &OpError{Op: "dial", Net: sd.network, Source: sd.LocalAddr, Addr: ra, Err: mapErr(ctx.Err())}
+		default:
+		}
+
+		dialCtx := ctx
+		if deadline, hasDeadline := ctx.Deadline(); hasDeadline {
+			partialDeadline, err := partialDeadline(time.Now(), deadline, len(ras)-i)
+			if err != nil {
+				// Ran out of time.
+				if firstErr == nil {
+					firstErr = &OpError{Op: "dial", Net: sd.network, Source: sd.LocalAddr, Addr: ra, Err: err}
+				}
+				break
+			}
+			if partialDeadline.Before(deadline) {
+				var cancel context.CancelFunc
+				dialCtx, cancel = context.WithDeadline(ctx, partialDeadline)
+				defer cancel()
+			}
+		}
+
+		c, err := sd.dialSingle(dialCtx, ra)
+		if err == nil {
+			return c, nil
+		}
+		if firstErr == nil {
+			firstErr = err
+		}
+	}
+
+	if firstErr == nil {
+		firstErr = &OpError{Op: "dial", Net: sd.network, Source: nil, Addr: nil, Err: errMissingAddress}
+	}
+	return nil, firstErr
+}
+
+// dialSingle attempts to establish and returns a single connection to
+// the destination address.
+func (sd *sysDialer) dialSingle(ctx context.Context, ra Addr) (c Conn, err error) {
+	trace, _ := ctx.Value(nettrace.TraceKey{}).(*nettrace.Trace)
+	if trace != nil {
+		raStr := ra.String()
+		if trace.ConnectStart != nil {
+			trace.ConnectStart(sd.network, raStr)
+		}
+		if trace.ConnectDone != nil {
+			defer func() { trace.ConnectDone(sd.network, raStr, err) }()
+		}
+	}
+	la := sd.LocalAddr
+	switch ra := ra.(type) {
+	case *TCPAddr:
+		la, _ := la.(*TCPAddr)
+		c, err = sd.dialTCP(ctx, la, ra)
+	case *UDPAddr:
+		la, _ := la.(*UDPAddr)
+		c, err = sd.dialUDP(ctx, la, ra)
+	case *IPAddr:
+		la, _ := la.(*IPAddr)
+		c, err = sd.dialIP(ctx, la, ra)
+	case *UnixAddr:
+		la, _ := la.(*UnixAddr)
+		c, err = sd.dialUnix(ctx, la, ra)
+	default:
+		return nil, &OpError{Op: "dial", Net: sd.network, Source: la, Addr: ra, Err: &AddrError{Err: "unexpected address type", Addr: sd.address}}
+	}
+	if err != nil {
+		return nil, &OpError{Op: "dial", Net: sd.network, Source: la, Addr: ra, Err: err} // c is non-nil interface containing nil pointer
+	}
+	return c, nil
+}
+
+// ListenConfig contains options for listening to an address.
+type ListenConfig struct {
+	// If Control is not nil, it is called after creating the network
+	// connection but before binding it to the operating system.
+	//
+	// Network and address parameters passed to Control method are not
+	// necessarily the ones passed to Listen. For example, passing "tcp" to
+	// Listen will cause the Control function to be called with "tcp4" or "tcp6".
+	Control func(network, address string, c syscall.RawConn) error
+
+	// KeepAlive specifies the keep-alive period for network
+	// connections accepted by this listener.
+	// If zero, keep-alives are enabled if supported by the protocol
+	// and operating system. Network protocols or operating systems
+	// that do not support keep-alives ignore this field.
+	// If negative, keep-alives are disabled.
+	KeepAlive time.Duration
+}
+
+// Listen announces on the local network address.
+//
+// See func Listen for a description of the network and address
+// parameters.
+func (lc *ListenConfig) Listen(ctx context.Context, network, address string) (Listener, error) {
+	addrs, err := DefaultResolver.resolveAddrList(ctx, "listen", network, address, nil)
+	if err != nil {
+		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: nil, Err: err}
+	}
+	sl := &sysListener{
+		ListenConfig: *lc,
+		network:      network,
+		address:      address,
+	}
+	var l Listener
+	la := addrs.first(isIPv4)
+	switch la := la.(type) {
+	case *TCPAddr:
+		l, err = sl.listenTCP(ctx, la)
+	case *UnixAddr:
+		l, err = sl.listenUnix(ctx, la)
+	default:
+		return nil, &OpError{Op: "listen", Net: sl.network, Source: nil, Addr: la, Err: &AddrError{Err: "unexpected address type", Addr: address}}
+	}
+	if err != nil {
+		return nil, &OpError{Op: "listen", Net: sl.network, Source: nil, Addr: la, Err: err} // l is non-nil interface containing nil pointer
+	}
+	return l, nil
+}
+
+// ListenPacket announces on the local network address.
+//
+// See func ListenPacket for a description of the network and address
+// parameters.
+func (lc *ListenConfig) ListenPacket(ctx context.Context, network, address string) (PacketConn, error) {
+	addrs, err := DefaultResolver.resolveAddrList(ctx, "listen", network, address, nil)
+	if err != nil {
+		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: nil, Err: err}
+	}
+	sl := &sysListener{
+		ListenConfig: *lc,
+		network:      network,
+		address:      address,
+	}
+	var c PacketConn
+	la := addrs.first(isIPv4)
+	switch la := la.(type) {
+	case *UDPAddr:
+		c, err = sl.listenUDP(ctx, la)
+	case *IPAddr:
+		c, err = sl.listenIP(ctx, la)
+	case *UnixAddr:
+		c, err = sl.listenUnixgram(ctx, la)
+	default:
+		return nil, &OpError{Op: "listen", Net: sl.network, Source: nil, Addr: la, Err: &AddrError{Err: "unexpected address type", Addr: address}}
+	}
+	if err != nil {
+		return nil, &OpError{Op: "listen", Net: sl.network, Source: nil, Addr: la, Err: err} // c is non-nil interface containing nil pointer
+	}
+	return c, nil
+}
+
+// sysListener contains a Listen's parameters and configuration.
+type sysListener struct {
+	ListenConfig
+	network, address string
+}
+
+// Listen announces on the local network address.
+//
+// The network must be "tcp", "tcp4", "tcp6", "unix" or "unixpacket".
+//
+// For TCP networks, if the host in the address parameter is empty or
+// a literal unspecified IP address, Listen listens on all available
+// unicast and anycast IP addresses of the local system.
+// To only use IPv4, use network "tcp4".
+// The address can use a host name, but this is not recommended,
+// because it will create a listener for at most one of the host's IP
+// addresses.
+// If the port in the address parameter is empty or "0", as in
+// "127.0.0.1:" or "[::1]:0", a port number is automatically chosen.
+// The Addr method of Listener can be used to discover the chosen
+// port.
+//
+// See func Dial for a description of the network and address
+// parameters.
+//
+// Listen uses context.Background internally; to specify the context, use
+// ListenConfig.Listen.
+func Listen(network, address string) (Listener, error) {
+	var lc ListenConfig
+	return lc.Listen(context.Background(), network, address)
+}
+
+// ListenPacket announces on the local network address.
+//
+// The network must be "udp", "udp4", "udp6", "unixgram", or an IP
+// transport. The IP transports are "ip", "ip4", or "ip6" followed by
+// a colon and a literal protocol number or a protocol name, as in
+// "ip:1" or "ip:icmp".
+//
+// For UDP and IP networks, if the host in the address parameter is
+// empty or a literal unspecified IP address, ListenPacket listens on
+// all available IP addresses of the local system except multicast IP
+// addresses.
+// To only use IPv4, use network "udp4" or "ip4:proto".
+// The address can use a host name, but this is not recommended,
+// because it will create a listener for at most one of the host's IP
+// addresses.
+// If the port in the address parameter is empty or "0", as in
+// "127.0.0.1:" or "[::1]:0", a port number is automatically chosen.
+// The LocalAddr method of PacketConn can be used to discover the
+// chosen port.
+//
+// See func Dial for a description of the network and address
+// parameters.
+//
+// ListenPacket uses context.Background internally; to specify the context, use
+// ListenConfig.ListenPacket.
+func ListenPacket(network, address string) (PacketConn, error) {
+	var lc ListenConfig
+	return lc.ListenPacket(context.Background(), network, address)
+}
diff --git a/contrib/go/_std_1.19/src/net/dnsclient.go b/contrib/go/_std_1.19/src/net/dnsclient.go
new file mode 100644
index 0000000000..b609dbd468
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/dnsclient.go
@@ -0,0 +1,228 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+	"internal/bytealg"
+	"internal/itoa"
+	"sort"
+
+	"golang.org/x/net/dns/dnsmessage"
+)
+
+// provided by runtime
+func fastrandu() uint
+
+func randInt() int {
+	return int(fastrandu() >> 1) // clear sign bit
+}
+
+func randIntn(n int) int {
+	return randInt() % n
+}
+
+// reverseaddr returns the in-addr.arpa. or ip6.arpa. hostname of the IP
+// address addr suitable for rDNS (PTR) record lookup or an error if it fails
+// to parse the IP address.
+func reverseaddr(addr string) (arpa string, err error) {
+	ip := ParseIP(addr)
+	if ip == nil {
+		return "", &DNSError{Err: "unrecognized address", Name: addr}
+	}
+	if ip.To4() != nil {
+		return itoa.Uitoa(uint(ip[15])) + "." + itoa.Uitoa(uint(ip[14])) + "." + itoa.Uitoa(uint(ip[13])) + "." + itoa.Uitoa(uint(ip[12])) + ".in-addr.arpa.", nil
+	}
+	// Must be IPv6
+	buf := make([]byte, 0, len(ip)*4+len("ip6.arpa."))
+	// Add it, in reverse, to the buffer
+	for i := len(ip) - 1; i >= 0; i-- {
+		v := ip[i]
+		buf = append(buf, hexDigit[v&0xF],
+			'.',
+			hexDigit[v>>4],
+			'.')
+	}
+	// Append "ip6.arpa." and return (buf already has the final .)
+	buf = append(buf, "ip6.arpa."...)
+	return string(buf), nil
+}
+
+func equalASCIIName(x, y dnsmessage.Name) bool {
+	if x.Length != y.Length {
+		return false
+	}
+	for i := 0; i < int(x.Length); i++ {
+		a := x.Data[i]
+		b := y.Data[i]
+		if 'A' <= a && a <= 'Z' {
+			a += 0x20
+		}
+		if 'A' <= b && b <= 'Z' {
+			b += 0x20
+		}
+		if a != b {
+			return false
+		}
+	}
+	return true
+}
+
+// isDomainName checks if a string is a presentation-format domain name
+// (currently restricted to hostname-compatible "preferred name" LDH labels and
+// SRV-like "underscore labels"; see golang.org/issue/12421).
+func isDomainName(s string) bool {
+	// The root domain name is valid. See golang.org/issue/45715.
+	if s == "." {
+		return true
+	}
+
+	// See RFC 1035, RFC 3696.
+	// Presentation format has dots before every label except the first, and the
+	// terminal empty label is optional here because we assume fully-qualified
+	// (absolute) input. We must therefore reserve space for the first and last
+	// labels' length octets in wire format, where they are necessary and the
+	// maximum total length is 255.
+	// So our _effective_ maximum is 253, but 254 is not rejected if the last
+	// character is a dot.
+	l := len(s)
+	if l == 0 || l > 254 || l == 254 && s[l-1] != '.' {
+		return false
+	}
+
+	last := byte('.')
+	nonNumeric := false // true once we've seen a letter or hyphen
+	partlen := 0
+	for i := 0; i < len(s); i++ {
+		c := s[i]
+		switch {
+		default:
+			return false
+		case 'a' <= c && c <= 'z' || 'A' <= c && c <= 'Z' || c == '_':
+			nonNumeric = true
+			partlen++
+		case '0' <= c && c <= '9':
+			// fine
+			partlen++
+		case c == '-':
+			// Byte before dash cannot be dot.
+			if last == '.' {
+				return false
+			}
+			partlen++
+			nonNumeric = true
+		case c == '.':
+			// Byte before dot cannot be dot, dash.
+			if last == '.' || last == '-' {
+				return false
+			}
+			if partlen > 63 || partlen == 0 {
+				return false
+			}
+			partlen = 0
+		}
+		last = c
+	}
+	if last == '-' || partlen > 63 {
+		return false
+	}
+
+	return nonNumeric
+}
+
+// absDomainName returns an absolute domain name which ends with a
+// trailing dot to match pure Go reverse resolver and all other lookup
+// routines.
+// See golang.org/issue/12189.
+// But we don't want to add dots for local names from /etc/hosts.
+// It's hard to tell so we settle on the heuristic that names without dots
+// (like "localhost" or "myhost") do not get trailing dots, but any other
+// names do.
+func absDomainName(s string) string {
+	if bytealg.IndexByteString(s, '.') != -1 && s[len(s)-1] != '.' {
+		s += "."
+	}
+	return s
+}
+
+// An SRV represents a single DNS SRV record.
+type SRV struct {
+	Target   string
+	Port     uint16
+	Priority uint16
+	Weight   uint16
+}
+
+// byPriorityWeight sorts SRV records by ascending priority and weight.
+type byPriorityWeight []*SRV
+
+func (s byPriorityWeight) Len() int { return len(s) }
+func (s byPriorityWeight) Less(i, j int) bool {
+	return s[i].Priority < s[j].Priority || (s[i].Priority == s[j].Priority && s[i].Weight < s[j].Weight)
+}
+func (s byPriorityWeight) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
+
+// shuffleByWeight shuffles SRV records by weight using the algorithm
+// described in RFC 2782.
+func (addrs byPriorityWeight) shuffleByWeight() {
+	sum := 0
+	for _, addr := range addrs {
+		sum += int(addr.Weight)
+	}
+	for sum > 0 && len(addrs) > 1 {
+		s := 0
+		n := randIntn(sum)
+		for i := range addrs {
+			s += int(addrs[i].Weight)
+			if s > n {
+				if i > 0 {
+					addrs[0], addrs[i] = addrs[i], addrs[0]
+				}
+				break
+			}
+		}
+		sum -= int(addrs[0].Weight)
+		addrs = addrs[1:]
+	}
+}
+
+// sort reorders SRV records as specified in RFC 2782.
+func (addrs byPriorityWeight) sort() {
+	sort.Sort(addrs)
+	i := 0
+	for j := 1; j < len(addrs); j++ {
+		if addrs[i].Priority != addrs[j].Priority {
+			addrs[i:j].shuffleByWeight()
+			i = j
+		}
+	}
+	addrs[i:].shuffleByWeight()
+}
+
+// An MX represents a single DNS MX record.
+type MX struct {
+	Host string
+	Pref uint16
+}
+
+// byPref implements sort.Interface to sort MX records by preference
+type byPref []*MX
+
+func (s byPref) Len() int           { return len(s) }
+func (s byPref) Less(i, j int) bool { return s[i].Pref < s[j].Pref }
+func (s byPref) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
+
+// sort reorders MX records as specified in RFC 5321.
+func (s byPref) sort() {
+	for i := range s {
+		j := randIntn(i + 1)
+		s[i], s[j] = s[j], s[i]
+	}
+	sort.Sort(s)
+}
+
+// An NS represents a single DNS NS record.
+type NS struct {
+	Host string
+}
diff --git a/contrib/go/_std_1.19/src/net/dnsclient_unix.go b/contrib/go/_std_1.19/src/net/dnsclient_unix.go
new file mode 100644
index 0000000000..088c81adee
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/dnsclient_unix.go
@@ -0,0 +1,826 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !js
+
+// DNS client: see RFC 1035.
+// Has to be linked into package net for Dial.
+
+// TODO(rsc):
+//	Could potentially handle many outstanding lookups faster.
+//	Random UDP source port (net.Dial should do that for us).
+//	Random request IDs.
+
+package net
+
+import (
+	"context"
+	"errors"
+	"internal/itoa"
+	"io"
+	"os"
+	"runtime"
+	"sync"
+	"time"
+
+	"golang.org/x/net/dns/dnsmessage"
+)
+
+const (
+	// to be used as a useTCP parameter to exchange
+	useTCPOnly  = true
+	useUDPOrTCP = false
+
+	// Maximum DNS packet size.
+	// Value taken from https://dnsflagday.net/2020/.
+	maxDNSPacketSize = 1232
+)
+
+var (
+	errLameReferral              = errors.New("lame referral")
+	errCannotUnmarshalDNSMessage = errors.New("cannot unmarshal DNS message")
+	errCannotMarshalDNSMessage   = errors.New("cannot marshal DNS message")
+	errServerMisbehaving         = errors.New("server misbehaving")
+	errInvalidDNSResponse        = errors.New("invalid DNS response")
+	errNoAnswerFromDNSServer     = errors.New("no answer from DNS server")
+
+	// errServerTemporarilyMisbehaving is like errServerMisbehaving, except
+	// that when it gets translated to a DNSError, the IsTemporary field
+	// gets set to true.
+	errServerTemporarilyMisbehaving = errors.New("server misbehaving")
+)
+
+func newRequest(q dnsmessage.Question) (id uint16, udpReq, tcpReq []byte, err error) {
+	id = uint16(randInt())
+	b := dnsmessage.NewBuilder(make([]byte, 2, 514), dnsmessage.Header{ID: id, RecursionDesired: true})
+	b.EnableCompression()
+	if err := b.StartQuestions(); err != nil {
+		return 0, nil, nil, err
+	}
+	if err := b.Question(q); err != nil {
+		return 0, nil, nil, err
+	}
+
+	// Accept packets up to maxDNSPacketSize.  RFC 6891.
+	if err := b.StartAdditionals(); err != nil {
+		return 0, nil, nil, err
+	}
+	var rh dnsmessage.ResourceHeader
+	if err := rh.SetEDNS0(maxDNSPacketSize, dnsmessage.RCodeSuccess, false); err != nil {
+		return 0, nil, nil, err
+	}
+	if err := b.OPTResource(rh, dnsmessage.OPTResource{}); err != nil {
+		return 0, nil, nil, err
+	}
+
+	tcpReq, err = b.Finish()
+	if err != nil {
+		return 0, nil, nil, err
+	}
+	udpReq = tcpReq[2:]
+	l := len(tcpReq) - 2
+	tcpReq[0] = byte(l >> 8)
+	tcpReq[1] = byte(l)
+	return id, udpReq, tcpReq, nil
+}
+
+func checkResponse(reqID uint16, reqQues dnsmessage.Question, respHdr dnsmessage.Header, respQues dnsmessage.Question) bool {
+	if !respHdr.Response {
+		return false
+	}
+	if reqID != respHdr.ID {
+		return false
+	}
+	if reqQues.Type != respQues.Type || reqQues.Class != respQues.Class || !equalASCIIName(reqQues.Name, respQues.Name) {
+		return false
+	}
+	return true
+}
+
+func dnsPacketRoundTrip(c Conn, id uint16, query dnsmessage.Question, b []byte) (dnsmessage.Parser, dnsmessage.Header, error) {
+	if _, err := c.Write(b); err != nil {
+		return dnsmessage.Parser{}, dnsmessage.Header{}, err
+	}
+
+	b = make([]byte, maxDNSPacketSize)
+	for {
+		n, err := c.Read(b)
+		if err != nil {
+			return dnsmessage.Parser{}, dnsmessage.Header{}, err
+		}
+		var p dnsmessage.Parser
+		// Ignore invalid responses as they may be malicious
+		// forgery attempts. Instead continue waiting until
+		// timeout. See golang.org/issue/13281.
+		h, err := p.Start(b[:n])
+		if err != nil {
+			continue
+		}
+		q, err := p.Question()
+		if err != nil || !checkResponse(id, query, h, q) {
+			continue
+		}
+		return p, h, nil
+	}
+}
+
+func dnsStreamRoundTrip(c Conn, id uint16, query dnsmessage.Question, b []byte) (dnsmessage.Parser, dnsmessage.Header, error) {
+	if _, err := c.Write(b); err != nil {
+		return dnsmessage.Parser{}, dnsmessage.Header{}, err
+	}
+
+	b = make([]byte, 1280) // 1280 is a reasonable initial size for IP over Ethernet, see RFC 4035
+	if _, err := io.ReadFull(c, b[:2]); err != nil {
+		return dnsmessage.Parser{}, dnsmessage.Header{}, err
+	}
+	l := int(b[0])<<8 | int(b[1])
+	if l > len(b) {
+		b = make([]byte, l)
+	}
+	n, err := io.ReadFull(c, b[:l])
+	if err != nil {
+		return dnsmessage.Parser{}, dnsmessage.Header{}, err
+	}
+	var p dnsmessage.Parser
+	h, err := p.Start(b[:n])
+	if err != nil {
+		return dnsmessage.Parser{}, dnsmessage.Header{}, errCannotUnmarshalDNSMessage
+	}
+	q, err := p.Question()
+	if err != nil {
+		return dnsmessage.Parser{}, dnsmessage.Header{}, errCannotUnmarshalDNSMessage
+	}
+	if !checkResponse(id, query, h, q) {
+		return dnsmessage.Parser{}, dnsmessage.Header{}, errInvalidDNSResponse
+	}
+	return p, h, nil
+}
+
+// exchange sends a query on the connection and hopes for a response.
+func (r *Resolver) exchange(ctx context.Context, server string, q dnsmessage.Question, timeout time.Duration, useTCP bool) (dnsmessage.Parser, dnsmessage.Header, error) {
+	q.Class = dnsmessage.ClassINET
+	id, udpReq, tcpReq, err := newRequest(q)
+	if err != nil {
+		return dnsmessage.Parser{}, dnsmessage.Header{}, errCannotMarshalDNSMessage
+	}
+	var networks []string
+	if useTCP {
+		networks = []string{"tcp"}
+	} else {
+		networks = []string{"udp", "tcp"}
+	}
+	for _, network := range networks {
+		ctx, cancel := context.WithDeadline(ctx, time.Now().Add(timeout))
+		defer cancel()
+
+		c, err := r.dial(ctx, network, server)
+		if err != nil {
+			return dnsmessage.Parser{}, dnsmessage.Header{}, err
+		}
+		if d, ok := ctx.Deadline(); ok && !d.IsZero() {
+			c.SetDeadline(d)
+		}
+		var p dnsmessage.Parser
+		var h dnsmessage.Header
+		if _, ok := c.(PacketConn); ok {
+			p, h, err = dnsPacketRoundTrip(c, id, q, udpReq)
+		} else {
+			p, h, err = dnsStreamRoundTrip(c, id, q, tcpReq)
+		}
+		c.Close()
+		if err != nil {
+			return dnsmessage.Parser{}, dnsmessage.Header{}, mapErr(err)
+		}
+		if err := p.SkipQuestion(); err != dnsmessage.ErrSectionDone {
+			return dnsmessage.Parser{}, dnsmessage.Header{}, errInvalidDNSResponse
+		}
+		if h.Truncated { // see RFC 5966
+			continue
+		}
+		return p, h, nil
+	}
+	return dnsmessage.Parser{}, dnsmessage.Header{}, errNoAnswerFromDNSServer
+}
+
+// checkHeader performs basic sanity checks on the header.
+func checkHeader(p *dnsmessage.Parser, h dnsmessage.Header) error {
+	if h.RCode == dnsmessage.RCodeNameError {
+		return errNoSuchHost
+	}
+
+	_, err := p.AnswerHeader()
+	if err != nil && err != dnsmessage.ErrSectionDone {
+		return errCannotUnmarshalDNSMessage
+	}
+
+	// libresolv continues to the next server when it receives
+	// an invalid referral response. See golang.org/issue/15434.
+	if h.RCode == dnsmessage.RCodeSuccess && !h.Authoritative && !h.RecursionAvailable && err == dnsmessage.ErrSectionDone {
+		return errLameReferral
+	}
+
+	if h.RCode != dnsmessage.RCodeSuccess && h.RCode != dnsmessage.RCodeNameError {
+		// None of the error codes make sense
+		// for the query we sent. If we didn't get
+		// a name error and we didn't get success,
+		// the server is behaving incorrectly or
+		// having temporary trouble.
+		if h.RCode == dnsmessage.RCodeServerFailure {
+			return errServerTemporarilyMisbehaving
+		}
+		return errServerMisbehaving
+	}
+
+	return nil
+}
+
+func skipToAnswer(p *dnsmessage.Parser, qtype dnsmessage.Type) error {
+	for {
+		h, err := p.AnswerHeader()
+		if err == dnsmessage.ErrSectionDone {
+			return errNoSuchHost
+		}
+		if err != nil {
+			return errCannotUnmarshalDNSMessage
+		}
+		if h.Type == qtype {
+			return nil
+		}
+		if err := p.SkipAnswer(); err != nil {
+			return errCannotUnmarshalDNSMessage
+		}
+	}
+}
+
+// Do a lookup for a single name, which must be rooted
+// (otherwise answer will not find the answers).
+func (r *Resolver) tryOneName(ctx context.Context, cfg *dnsConfig, name string, qtype dnsmessage.Type) (dnsmessage.Parser, string, error) {
+	var lastErr error
+	serverOffset := cfg.serverOffset()
+	sLen := uint32(len(cfg.servers))
+
+	n, err := dnsmessage.NewName(name)
+	if err != nil {
+		return dnsmessage.Parser{}, "", errCannotMarshalDNSMessage
+	}
+	q := dnsmessage.Question{
+		Name:  n,
+		Type:  qtype,
+		Class: dnsmessage.ClassINET,
+	}
+
+	for i := 0; i < cfg.attempts; i++ {
+		for j := uint32(0); j < sLen; j++ {
+			server := cfg.servers[(serverOffset+j)%sLen]
+
+			p, h, err := r.exchange(ctx, server, q, cfg.timeout, cfg.useTCP)
+			if err != nil {
+				dnsErr := &DNSError{
+					Err:    err.Error(),
+					Name:   name,
+					Server: server,
+				}
+				if nerr, ok := err.(Error); ok && nerr.Timeout() {
+					dnsErr.IsTimeout = true
+				}
+				// Set IsTemporary for socket-level errors. Note that this flag
+				// may also be used to indicate a SERVFAIL response.
+				if _, ok := err.(*OpError); ok {
+					dnsErr.IsTemporary = true
+				}
+				lastErr = dnsErr
+				continue
+			}
+
+			if err := checkHeader(&p, h); err != nil {
+				dnsErr := &DNSError{
+					Err:    err.Error(),
+					Name:   name,
+					Server: server,
+				}
+				if err == errServerTemporarilyMisbehaving {
+					dnsErr.IsTemporary = true
+				}
+				if err == errNoSuchHost {
+					// The name does not exist, so trying
+					// another server won't help.
+
+					dnsErr.IsNotFound = true
+					return p, server, dnsErr
+				}
+				lastErr = dnsErr
+				continue
+			}
+
+			err = skipToAnswer(&p, qtype)
+			if err == nil {
+				return p, server, nil
+			}
+			lastErr = &DNSError{
+				Err:    err.Error(),
+				Name:   name,
+				Server: server,
+			}
+			if err == errNoSuchHost {
+				// The name does not exist, so trying another
+				// server won't help.
+
+				lastErr.(*DNSError).IsNotFound = true
+				return p, server, lastErr
+			}
+		}
+	}
+	return dnsmessage.Parser{}, "", lastErr
+}
+
+// A resolverConfig represents a DNS stub resolver configuration.
+type resolverConfig struct {
+	initOnce sync.Once // guards init of resolverConfig
+
+	// ch is used as a semaphore that only allows one lookup at a
+	// time to recheck resolv.conf.
+	ch          chan struct{} // guards lastChecked and modTime
+	lastChecked time.Time     // last time resolv.conf was checked
+
+	mu        sync.RWMutex // protects dnsConfig
+	dnsConfig *dnsConfig   // parsed resolv.conf structure used in lookups
+}
+
+var resolvConf resolverConfig
+
+// init initializes conf and is only called via conf.initOnce.
+func (conf *resolverConfig) init() {
+	// Set dnsConfig and lastChecked so we don't parse
+	// resolv.conf twice the first time.
+	conf.dnsConfig = systemConf().resolv
+	if conf.dnsConfig == nil {
+		conf.dnsConfig = dnsReadConfig("/etc/resolv.conf")
+	}
+	conf.lastChecked = time.Now()
+
+	// Prepare ch so that only one update of resolverConfig may
+	// run at once.
+	conf.ch = make(chan struct{}, 1)
+}
+
+// tryUpdate tries to update conf with the named resolv.conf file.
+// The name variable only exists for testing. It is otherwise always
+// "/etc/resolv.conf".
+func (conf *resolverConfig) tryUpdate(name string) {
+	conf.initOnce.Do(conf.init)
+
+	// Ensure only one update at a time checks resolv.conf.
+	if !conf.tryAcquireSema() {
+		return
+	}
+	defer conf.releaseSema()
+
+	now := time.Now()
+	if conf.lastChecked.After(now.Add(-5 * time.Second)) {
+		return
+	}
+	conf.lastChecked = now
+
+	switch runtime.GOOS {
+	case "windows":
+		// There's no file on disk, so don't bother checking
+		// and failing.
+		//
+		// The Windows implementation of dnsReadConfig (called
+		// below) ignores the name.
+	default:
+		var mtime time.Time
+		if fi, err := os.Stat(name); err == nil {
+			mtime = fi.ModTime()
+		}
+		if mtime.Equal(conf.dnsConfig.mtime) {
+			return
+		}
+	}
+
+	dnsConf := dnsReadConfig(name)
+	conf.mu.Lock()
+	conf.dnsConfig = dnsConf
+	conf.mu.Unlock()
+}
+
+func (conf *resolverConfig) tryAcquireSema() bool {
+	select {
+	case conf.ch <- struct{}{}:
+		return true
+	default:
+		return false
+	}
+}
+
+func (conf *resolverConfig) releaseSema() {
+	<-conf.ch
+}
+
+func (r *Resolver) lookup(ctx context.Context, name string, qtype dnsmessage.Type) (dnsmessage.Parser, string, error) {
+	if !isDomainName(name) {
+		// We used to use "invalid domain name" as the error,
+		// but that is a detail of the specific lookup mechanism.
+		// Other lookups might allow broader name syntax
+		// (for example Multicast DNS allows UTF-8; see RFC 6762).
+		// For consistency with libc resolvers, report no such host.
+		return dnsmessage.Parser{}, "", &DNSError{Err: errNoSuchHost.Error(), Name: name, IsNotFound: true}
+	}
+	resolvConf.tryUpdate("/etc/resolv.conf")
+	resolvConf.mu.RLock()
+	conf := resolvConf.dnsConfig
+	resolvConf.mu.RUnlock()
+	var (
+		p      dnsmessage.Parser
+		server string
+		err    error
+	)
+	for _, fqdn := range conf.nameList(name) {
+		p, server, err = r.tryOneName(ctx, conf, fqdn, qtype)
+		if err == nil {
+			break
+		}
+		if nerr, ok := err.(Error); ok && nerr.Temporary() && r.strictErrors() {
+			// If we hit a temporary error with StrictErrors enabled,
+			// stop immediately instead of trying more names.
+			break
+		}
+	}
+	if err == nil {
+		return p, server, nil
+	}
+	if err, ok := err.(*DNSError); ok {
+		// Show original name passed to lookup, not suffixed one.
+		// In general we might have tried many suffixes; showing
+		// just one is misleading. See also golang.org/issue/6324.
+		err.Name = name
+	}
+	return dnsmessage.Parser{}, "", err
+}
+
+// avoidDNS reports whether this is a hostname for which we should not
+// use DNS. Currently this includes only .onion, per RFC 7686. See
+// golang.org/issue/13705. Does not cover .local names (RFC 6762),
+// see golang.org/issue/16739.
+func avoidDNS(name string) bool {
+	if name == "" {
+		return true
+	}
+	if name[len(name)-1] == '.' {
+		name = name[:len(name)-1]
+	}
+	return stringsHasSuffixFold(name, ".onion")
+}
+
+// nameList returns a list of names for sequential DNS queries.
+func (conf *dnsConfig) nameList(name string) []string {
+	if avoidDNS(name) {
+		return nil
+	}
+
+	// Check name length (see isDomainName).
+	l := len(name)
+	rooted := l > 0 && name[l-1] == '.'
+	if l > 254 || l == 254 && rooted {
+		return nil
+	}
+
+	// If name is rooted (trailing dot), try only that name.
+	if rooted {
+		return []string{name}
+	}
+
+	hasNdots := count(name, '.') >= conf.ndots
+	name += "."
+	l++
+
+	// Build list of search choices.
+	names := make([]string, 0, 1+len(conf.search))
+	// If name has enough dots, try unsuffixed first.
+	if hasNdots {
+		names = append(names, name)
+	}
+	// Try suffixes that are not too long (see isDomainName).
+	for _, suffix := range conf.search {
+		if l+len(suffix) <= 254 {
+			names = append(names, name+suffix)
+		}
+	}
+	// Try unsuffixed, if not tried first above.
+	if !hasNdots {
+		names = append(names, name)
+	}
+	return names
+}
+
+// hostLookupOrder specifies the order of LookupHost lookup strategies.
+// It is basically a simplified representation of nsswitch.conf.
+// "files" means /etc/hosts.
+type hostLookupOrder int
+
+const (
+	// hostLookupCgo means defer to cgo.
+	hostLookupCgo      hostLookupOrder = iota
+	hostLookupFilesDNS                 // files first
+	hostLookupDNSFiles                 // dns first
+	hostLookupFiles                    // only files
+	hostLookupDNS                      // only DNS
+)
+
+var lookupOrderName = map[hostLookupOrder]string{
+	hostLookupCgo:      "cgo",
+	hostLookupFilesDNS: "files,dns",
+	hostLookupDNSFiles: "dns,files",
+	hostLookupFiles:    "files",
+	hostLookupDNS:      "dns",
+}
+
+func (o hostLookupOrder) String() string {
+	if s, ok := lookupOrderName[o]; ok {
+		return s
+	}
+	return "hostLookupOrder=" + itoa.Itoa(int(o)) + "??"
+}
+
+// goLookupHost is the native Go implementation of LookupHost.
+// Used only if cgoLookupHost refuses to handle the request
+// (that is, only if cgoLookupHost is the stub in cgo_stub.go).
+// Normally we let cgo use the C library resolver instead of
+// depending on our lookup code, so that Go and C get the same
+// answers.
+func (r *Resolver) goLookupHost(ctx context.Context, name string) (addrs []string, err error) {
+	return r.goLookupHostOrder(ctx, name, hostLookupFilesDNS)
+}
+
+func (r *Resolver) goLookupHostOrder(ctx context.Context, name string, order hostLookupOrder) (addrs []string, err error) {
+	if order == hostLookupFilesDNS || order == hostLookupFiles {
+		// Use entries from /etc/hosts if they match.
+		addrs = lookupStaticHost(name)
+		if len(addrs) > 0 || order == hostLookupFiles {
+			return
+		}
+	}
+	ips, _, err := r.goLookupIPCNAMEOrder(ctx, "ip", name, order)
+	if err != nil {
+		return
+	}
+	addrs = make([]string, 0, len(ips))
+	for _, ip := range ips {
+		addrs = append(addrs, ip.String())
+	}
+	return
+}
+
+// lookup entries from /etc/hosts
+func goLookupIPFiles(name string) (addrs []IPAddr) {
+	for _, haddr := range lookupStaticHost(name) {
+		haddr, zone := splitHostZone(haddr)
+		if ip := ParseIP(haddr); ip != nil {
+			addr := IPAddr{IP: ip, Zone: zone}
+			addrs = append(addrs, addr)
+		}
+	}
+	sortByRFC6724(addrs)
+	return
+}
+
+// goLookupIP is the native Go implementation of LookupIP.
+// The libc versions are in cgo_*.go.
+func (r *Resolver) goLookupIP(ctx context.Context, network, host string) (addrs []IPAddr, err error) {
+	order := systemConf().hostLookupOrder(r, host)
+	addrs, _, err = r.goLookupIPCNAMEOrder(ctx, network, host, order)
+	return
+}
+
+func (r *Resolver) goLookupIPCNAMEOrder(ctx context.Context, network, name string, order hostLookupOrder) (addrs []IPAddr, cname dnsmessage.Name, err error) {
+	if order == hostLookupFilesDNS || order == hostLookupFiles {
+		addrs = goLookupIPFiles(name)
+		if len(addrs) > 0 || order == hostLookupFiles {
+			return addrs, dnsmessage.Name{}, nil
+		}
+	}
+	if !isDomainName(name) {
+		// See comment in func lookup above about use of errNoSuchHost.
+		return nil, dnsmessage.Name{}, &DNSError{Err: errNoSuchHost.Error(), Name: name, IsNotFound: true}
+	}
+	resolvConf.tryUpdate("/etc/resolv.conf")
+	resolvConf.mu.RLock()
+	conf := resolvConf.dnsConfig
+	resolvConf.mu.RUnlock()
+	type result struct {
+		p      dnsmessage.Parser
+		server string
+		error
+	}
+	lane := make(chan result, 1)
+	qtypes := []dnsmessage.Type{dnsmessage.TypeA, dnsmessage.TypeAAAA}
+	switch ipVersion(network) {
+	case '4':
+		qtypes = []dnsmessage.Type{dnsmessage.TypeA}
+	case '6':
+		qtypes = []dnsmessage.Type{dnsmessage.TypeAAAA}
+	}
+	var queryFn func(fqdn string, qtype dnsmessage.Type)
+	var responseFn func(fqdn string, qtype dnsmessage.Type) result
+	if conf.singleRequest {
+		queryFn = func(fqdn string, qtype dnsmessage.Type) {}
+		responseFn = func(fqdn string, qtype dnsmessage.Type) result {
+			dnsWaitGroup.Add(1)
+			defer dnsWaitGroup.Done()
+			p, server, err := r.tryOneName(ctx, conf, fqdn, qtype)
+			return result{p, server, err}
+		}
+	} else {
+		queryFn = func(fqdn string, qtype dnsmessage.Type) {
+			dnsWaitGroup.Add(1)
+			go func(qtype dnsmessage.Type) {
+				p, server, err := r.tryOneName(ctx, conf, fqdn, qtype)
+				lane <- result{p, server, err}
+				dnsWaitGroup.Done()
+			}(qtype)
+		}
+		responseFn = func(fqdn string, qtype dnsmessage.Type) result {
+			return <-lane
+		}
+	}
+	var lastErr error
+	for _, fqdn := range conf.nameList(name) {
+		for _, qtype := range qtypes {
+			queryFn(fqdn, qtype)
+		}
+		hitStrictError := false
+		for _, qtype := range qtypes {
+			result := responseFn(fqdn, qtype)
+			if result.error != nil {
+				if nerr, ok := result.error.(Error); ok && nerr.Temporary() && r.strictErrors() {
+					// This error will abort the nameList loop.
+					hitStrictError = true
+					lastErr = result.error
+				} else if lastErr == nil || fqdn == name+"." {
+					// Prefer error for original name.
+					lastErr = result.error
+				}
+				continue
+			}
+
+			// Presotto says it's okay to assume that servers listed in
+			// /etc/resolv.conf are recursive resolvers.
+			//
+			// We asked for recursion, so it should have included all the
+			// answers we need in this one packet.
+			//
+			// Further, RFC 1035 section 4.3.1 says that "the recursive
+			// response to a query will be... The answer to the query,
+			// possibly preface by one or more CNAME RRs that specify
+			// aliases encountered on the way to an answer."
+			//
+			// Therefore, we should be able to assume that we can ignore
+			// CNAMEs and that the A and AAAA records we requested are
+			// for the canonical name.
+
+		loop:
+			for {
+				h, err := result.p.AnswerHeader()
+				if err != nil && err != dnsmessage.ErrSectionDone {
+					lastErr = &DNSError{
+						Err:    "cannot marshal DNS message",
+						Name:   name,
+						Server: result.server,
+					}
+				}
+				if err != nil {
+					break
+				}
+				switch h.Type {
+				case dnsmessage.TypeA:
+					a, err := result.p.AResource()
+					if err != nil {
+						lastErr = &DNSError{
+							Err:    "cannot marshal DNS message",
+							Name:   name,
+							Server: result.server,
+						}
+						break loop
+					}
+					addrs = append(addrs, IPAddr{IP: IP(a.A[:])})
+
+				case dnsmessage.TypeAAAA:
+					aaaa, err := result.p.AAAAResource()
+					if err != nil {
+						lastErr = &DNSError{
+							Err:    "cannot marshal DNS message",
+							Name:   name,
+							Server: result.server,
+						}
+						break loop
+					}
+					addrs = append(addrs, IPAddr{IP: IP(aaaa.AAAA[:])})
+
+				default:
+					if err := result.p.SkipAnswer(); err != nil {
+						lastErr = &DNSError{
+							Err:    "cannot marshal DNS message",
+							Name:   name,
+							Server: result.server,
+						}
+						break loop
+					}
+					continue
+				}
+				if cname.Length == 0 && h.Name.Length != 0 {
+					cname = h.Name
+				}
+			}
+		}
+		if hitStrictError {
+			// If either family hit an error with StrictErrors enabled,
+			// discard all addresses. This ensures that network flakiness
+			// cannot turn a dualstack hostname IPv4/IPv6-only.
+			addrs = nil
+			break
+		}
+		if len(addrs) > 0 {
+			break
+		}
+	}
+	if lastErr, ok := lastErr.(*DNSError); ok {
+		// Show original name passed to lookup, not suffixed one.
+		// In general we might have tried many suffixes; showing
+		// just one is misleading. See also golang.org/issue/6324.
+		lastErr.Name = name
+	}
+	sortByRFC6724(addrs)
+	if len(addrs) == 0 {
+		if order == hostLookupDNSFiles {
+			addrs = goLookupIPFiles(name)
+		}
+		if len(addrs) == 0 && lastErr != nil {
+			return nil, dnsmessage.Name{}, lastErr
+		}
+	}
+	return addrs, cname, nil
+}
+
+// goLookupCNAME is the native Go (non-cgo) implementation of LookupCNAME.
+func (r *Resolver) goLookupCNAME(ctx context.Context, host string) (string, error) {
+	order := systemConf().hostLookupOrder(r, host)
+	_, cname, err := r.goLookupIPCNAMEOrder(ctx, "ip", host, order)
+	return cname.String(), err
+}
+
+// goLookupPTR is the native Go implementation of LookupAddr.
+// Used only if cgoLookupPTR refuses to handle the request (that is,
+// only if cgoLookupPTR is the stub in cgo_stub.go).
+// Normally we let cgo use the C library resolver instead of depending
+// on our lookup code, so that Go and C get the same answers.
+func (r *Resolver) goLookupPTR(ctx context.Context, addr string) ([]string, error) {
+	names := lookupStaticAddr(addr)
+	if len(names) > 0 {
+		return names, nil
+	}
+	arpa, err := reverseaddr(addr)
+	if err != nil {
+		return nil, err
+	}
+	p, server, err := r.lookup(ctx, arpa, dnsmessage.TypePTR)
+	if err != nil {
+		return nil, err
+	}
+	var ptrs []string
+	for {
+		h, err := p.AnswerHeader()
+		if err == dnsmessage.ErrSectionDone {
+			break
+		}
+		if err != nil {
+			return nil, &DNSError{
+				Err:    "cannot marshal DNS message",
+				Name:   addr,
+				Server: server,
+			}
+		}
+		if h.Type != dnsmessage.TypePTR {
+			err := p.SkipAnswer()
+			if err != nil {
+				return nil, &DNSError{
+					Err:    "cannot marshal DNS message",
+					Name:   addr,
+					Server: server,
+				}
+			}
+			continue
+		}
+		ptr, err := p.PTRResource()
+		if err != nil {
+			return nil, &DNSError{
+				Err:    "cannot marshal DNS message",
+				Name:   addr,
+				Server: server,
+			}
+		}
+		ptrs = append(ptrs, ptr.PTR.String())
+
+	}
+	return ptrs, nil
+}
diff --git a/contrib/go/_std_1.19/src/net/dnsconfig.go b/contrib/go/_std_1.19/src/net/dnsconfig.go
new file mode 100644
index 0000000000..091b548301
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/dnsconfig.go
@@ -0,0 +1,43 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+	"os"
+	"sync/atomic"
+	"time"
+)
+
+var (
+	defaultNS   = []string{"127.0.0.1:53", "[::1]:53"}
+	getHostname = os.Hostname // variable for testing
+)
+
+type dnsConfig struct {
+	servers       []string      // server addresses (in host:port form) to use
+	search        []string      // rooted suffixes to append to local name
+	ndots         int           // number of dots in name to trigger absolute lookup
+	timeout       time.Duration // wait before giving up on a query, including retries
+	attempts      int           // lost packets before giving up on server
+	rotate        bool          // round robin among servers
+	unknownOpt    bool          // anything unknown was encountered
+	lookup        []string      // OpenBSD top-level database "lookup" order
+	err           error         // any error that occurs during open of resolv.conf
+	mtime         time.Time     // time of resolv.conf modification
+	soffset       uint32        // used by serverOffset
+	singleRequest bool          // use sequential A and AAAA queries instead of parallel queries
+	useTCP        bool          // force usage of TCP for DNS resolutions
+}
+
+// serverOffset returns an offset that can be used to determine
+// indices of servers in c.servers when making queries.
+// When the rotate option is enabled, this offset increases.
+// Otherwise it is always 0.
+func (c *dnsConfig) serverOffset() uint32 {
+	if c.rotate {
+		return atomic.AddUint32(&c.soffset, 1) - 1 // return 0 to start
+	}
+	return 0
+}
diff --git a/contrib/go/_std_1.19/src/net/dnsconfig_unix.go b/contrib/go/_std_1.19/src/net/dnsconfig_unix.go
new file mode 100644
index 0000000000..94cd09ec71
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/dnsconfig_unix.go
@@ -0,0 +1,157 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !js && !windows
+
+// Read system DNS config from /etc/resolv.conf
+
+package net
+
+import (
+	"internal/bytealg"
+	"time"
+)
+
+// See resolv.conf(5) on a Linux machine.
+func dnsReadConfig(filename string) *dnsConfig {
+	conf := &dnsConfig{
+		ndots:    1,
+		timeout:  5 * time.Second,
+		attempts: 2,
+	}
+	file, err := open(filename)
+	if err != nil {
+		conf.servers = defaultNS
+		conf.search = dnsDefaultSearch()
+		conf.err = err
+		return conf
+	}
+	defer file.close()
+	if fi, err := file.file.Stat(); err == nil {
+		conf.mtime = fi.ModTime()
+	} else {
+		conf.servers = defaultNS
+		conf.search = dnsDefaultSearch()
+		conf.err = err
+		return conf
+	}
+	for line, ok := file.readLine(); ok; line, ok = file.readLine() {
+		if len(line) > 0 && (line[0] == ';' || line[0] == '#') {
+			// comment.
+			continue
+		}
+		f := getFields(line)
+		if len(f) < 1 {
+			continue
+		}
+		switch f[0] {
+		case "nameserver": // add one name server
+			if len(f) > 1 && len(conf.servers) < 3 { // small, but the standard limit
+				// One more check: make sure server name is
+				// just an IP address. Otherwise we need DNS
+				// to look it up.
+				if parseIPv4(f[1]) != nil {
+					conf.servers = append(conf.servers, JoinHostPort(f[1], "53"))
+				} else if ip, _ := parseIPv6Zone(f[1]); ip != nil {
+					conf.servers = append(conf.servers, JoinHostPort(f[1], "53"))
+				}
+			}
+
+		case "domain": // set search path to just this domain
+			if len(f) > 1 {
+				conf.search = []string{ensureRooted(f[1])}
+			}
+
+		case "search": // set search path to given servers
+			conf.search = make([]string, len(f)-1)
+			for i := 0; i < len(conf.search); i++ {
+				conf.search[i] = ensureRooted(f[i+1])
+			}
+
+		case "options": // magic options
+			for _, s := range f[1:] {
+				switch {
+				case hasPrefix(s, "ndots:"):
+					n, _, _ := dtoi(s[6:])
+					if n < 0 {
+						n = 0
+					} else if n > 15 {
+						n = 15
+					}
+					conf.ndots = n
+				case hasPrefix(s, "timeout:"):
+					n, _, _ := dtoi(s[8:])
+					if n < 1 {
+						n = 1
+					}
+					conf.timeout = time.Duration(n) * time.Second
+				case hasPrefix(s, "attempts:"):
+					n, _, _ := dtoi(s[9:])
+					if n < 1 {
+						n = 1
+					}
+					conf.attempts = n
+				case s == "rotate":
+					conf.rotate = true
+				case s == "single-request" || s == "single-request-reopen":
+					// Linux option:
+					// http://man7.org/linux/man-pages/man5/resolv.conf.5.html
+					// "By default, glibc performs IPv4 and IPv6 lookups in parallel [...]
+					//  This option disables the behavior and makes glibc
+					//  perform the IPv6 and IPv4 requests sequentially."
+					conf.singleRequest = true
+				case s == "use-vc" || s == "usevc" || s == "tcp":
+					// Linux (use-vc), FreeBSD (usevc) and OpenBSD (tcp) option:
+					// http://man7.org/linux/man-pages/man5/resolv.conf.5.html
+					// "Sets RES_USEVC in _res.options.
+					//  This option forces the use of TCP for DNS resolutions."
+					// https://www.freebsd.org/cgi/man.cgi?query=resolv.conf&sektion=5&manpath=freebsd-release-ports
+					// https://man.openbsd.org/resolv.conf.5
+					conf.useTCP = true
+				default:
+					conf.unknownOpt = true
+				}
+			}
+
+		case "lookup":
+			// OpenBSD option:
+			// https://www.openbsd.org/cgi-bin/man.cgi/OpenBSD-current/man5/resolv.conf.5
+			// "the legal space-separated values are: bind, file, yp"
+			conf.lookup = f[1:]
+
+		default:
+			conf.unknownOpt = true
+		}
+	}
+	if len(conf.servers) == 0 {
+		conf.servers = defaultNS
+	}
+	if len(conf.search) == 0 {
+		conf.search = dnsDefaultSearch()
+	}
+	return conf
+}
+
+func dnsDefaultSearch() []string {
+	hn, err := getHostname()
+	if err != nil {
+		// best effort
+		return nil
+	}
+	if i := bytealg.IndexByteString(hn, '.'); i >= 0 && i < len(hn)-1 {
+		return []string{ensureRooted(hn[i+1:])}
+	}
+	return nil
+}
+
+func hasPrefix(s, prefix string) bool {
+	return len(s) >= len(prefix) && s[:len(prefix)] == prefix
+}
+
+func ensureRooted(s string) string {
+	if len(s) > 0 && s[len(s)-1] == '.' {
+		return s
+	}
+	return s + "."
+}
diff --git a/contrib/go/_std_1.19/src/net/error_posix.go b/contrib/go/_std_1.19/src/net/error_posix.go
new file mode 100644
index 0000000000..8fc7d0bb73
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/error_posix.go
@@ -0,0 +1,21 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm) || windows
+
+package net
+
+import (
+	"os"
+	"syscall"
+)
+
+// wrapSyscallError takes an error and a syscall name. If the error is
+// a syscall.Errno, it wraps it in a os.SyscallError using the syscall name.
+func wrapSyscallError(name string, err error) error {
+	if _, ok := err.(syscall.Errno); ok {
+		err = os.NewSyscallError(name, err)
+	}
+	return err
+}
diff --git a/contrib/go/_std_1.19/src/net/error_unix.go b/contrib/go/_std_1.19/src/net/error_unix.go
new file mode 100644
index 0000000000..1f9b6eb78c
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/error_unix.go
@@ -0,0 +1,16 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || js
+
+package net
+
+import "syscall"
+
+func isConnError(err error) bool {
+	if se, ok := err.(syscall.Errno); ok {
+		return se == syscall.ECONNRESET || se == syscall.ECONNABORTED
+	}
+	return false
+}
diff --git a/contrib/go/_std_1.19/src/net/fd_posix.go b/contrib/go/_std_1.19/src/net/fd_posix.go
new file mode 100644
index 0000000000..ffb9bcf8b9
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/fd_posix.go
@@ -0,0 +1,147 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || windows
+
+package net
+
+import (
+	"internal/poll"
+	"runtime"
+	"syscall"
+	"time"
+)
+
+// Network file descriptor.
+type netFD struct {
+	pfd poll.FD
+
+	// immutable until Close
+	family      int
+	sotype      int
+	isConnected bool // handshake completed or use of association with peer
+	net         string
+	laddr       Addr
+	raddr       Addr
+}
+
+func (fd *netFD) setAddr(laddr, raddr Addr) {
+	fd.laddr = laddr
+	fd.raddr = raddr
+	runtime.SetFinalizer(fd, (*netFD).Close)
+}
+
+func (fd *netFD) Close() error {
+	runtime.SetFinalizer(fd, nil)
+	return fd.pfd.Close()
+}
+
+func (fd *netFD) shutdown(how int) error {
+	err := fd.pfd.Shutdown(how)
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("shutdown", err)
+}
+
+func (fd *netFD) closeRead() error {
+	return fd.shutdown(syscall.SHUT_RD)
+}
+
+func (fd *netFD) closeWrite() error {
+	return fd.shutdown(syscall.SHUT_WR)
+}
+
+func (fd *netFD) Read(p []byte) (n int, err error) {
+	n, err = fd.pfd.Read(p)
+	runtime.KeepAlive(fd)
+	return n, wrapSyscallError(readSyscallName, err)
+}
+
+func (fd *netFD) readFrom(p []byte) (n int, sa syscall.Sockaddr, err error) {
+	n, sa, err = fd.pfd.ReadFrom(p)
+	runtime.KeepAlive(fd)
+	return n, sa, wrapSyscallError(readFromSyscallName, err)
+}
+func (fd *netFD) readFromInet4(p []byte, from *syscall.SockaddrInet4) (n int, err error) {
+	n, err = fd.pfd.ReadFromInet4(p, from)
+	runtime.KeepAlive(fd)
+	return n, wrapSyscallError(readFromSyscallName, err)
+}
+
+func (fd *netFD) readFromInet6(p []byte, from *syscall.SockaddrInet6) (n int, err error) {
+	n, err = fd.pfd.ReadFromInet6(p, from)
+	runtime.KeepAlive(fd)
+	return n, wrapSyscallError(readFromSyscallName, err)
+}
+
+func (fd *netFD) readMsg(p []byte, oob []byte, flags int) (n, oobn, retflags int, sa syscall.Sockaddr, err error) {
+	n, oobn, retflags, sa, err = fd.pfd.ReadMsg(p, oob, flags)
+	runtime.KeepAlive(fd)
+	return n, oobn, retflags, sa, wrapSyscallError(readMsgSyscallName, err)
+}
+
+func (fd *netFD) readMsgInet4(p []byte, oob []byte, flags int, sa *syscall.SockaddrInet4) (n, oobn, retflags int, err error) {
+	n, oobn, retflags, err = fd.pfd.ReadMsgInet4(p, oob, flags, sa)
+	runtime.KeepAlive(fd)
+	return n, oobn, retflags, wrapSyscallError(readMsgSyscallName, err)
+}
+
+func (fd *netFD) readMsgInet6(p []byte, oob []byte, flags int, sa *syscall.SockaddrInet6) (n, oobn, retflags int, err error) {
+	n, oobn, retflags, err = fd.pfd.ReadMsgInet6(p, oob, flags, sa)
+	runtime.KeepAlive(fd)
+	return n, oobn, retflags, wrapSyscallError(readMsgSyscallName, err)
+}
+
+func (fd *netFD) Write(p []byte) (nn int, err error) {
+	nn, err = fd.pfd.Write(p)
+	runtime.KeepAlive(fd)
+	return nn, wrapSyscallError(writeSyscallName, err)
+}
+
+func (fd *netFD) writeTo(p []byte, sa syscall.Sockaddr) (n int, err error) {
+	n, err = fd.pfd.WriteTo(p, sa)
+	runtime.KeepAlive(fd)
+	return n, wrapSyscallError(writeToSyscallName, err)
+}
+
+func (fd *netFD) writeToInet4(p []byte, sa *syscall.SockaddrInet4) (n int, err error) {
+	n, err = fd.pfd.WriteToInet4(p, sa)
+	runtime.KeepAlive(fd)
+	return n, wrapSyscallError(writeToSyscallName, err)
+}
+
+func (fd *netFD) writeToInet6(p []byte, sa *syscall.SockaddrInet6) (n int, err error) {
+	n, err = fd.pfd.WriteToInet6(p, sa)
+	runtime.KeepAlive(fd)
+	return n, wrapSyscallError(writeToSyscallName, err)
+}
+
+func (fd *netFD) writeMsg(p []byte, oob []byte, sa syscall.Sockaddr) (n int, oobn int, err error) {
+	n, oobn, err = fd.pfd.WriteMsg(p, oob, sa)
+	runtime.KeepAlive(fd)
+	return n, oobn, wrapSyscallError(writeMsgSyscallName, err)
+}
+
+func (fd *netFD) writeMsgInet4(p []byte, oob []byte, sa *syscall.SockaddrInet4) (n int, oobn int, err error) {
+	n, oobn, err = fd.pfd.WriteMsgInet4(p, oob, sa)
+	runtime.KeepAlive(fd)
+	return n, oobn, wrapSyscallError(writeMsgSyscallName, err)
+}
+
+func (fd *netFD) writeMsgInet6(p []byte, oob []byte, sa *syscall.SockaddrInet6) (n int, oobn int, err error) {
+	n, oobn, err = fd.pfd.WriteMsgInet6(p, oob, sa)
+	runtime.KeepAlive(fd)
+	return n, oobn, wrapSyscallError(writeMsgSyscallName, err)
+}
+
+func (fd *netFD) SetDeadline(t time.Time) error {
+	return fd.pfd.SetDeadline(t)
+}
+
+func (fd *netFD) SetReadDeadline(t time.Time) error {
+	return fd.pfd.SetReadDeadline(t)
+}
+
+func (fd *netFD) SetWriteDeadline(t time.Time) error {
+	return fd.pfd.SetWriteDeadline(t)
+}
diff --git a/contrib/go/_std_1.19/src/net/fd_unix.go b/contrib/go/_std_1.19/src/net/fd_unix.go
new file mode 100644
index 0000000000..a400c6075e
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/fd_unix.go
@@ -0,0 +1,203 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix
+
+package net
+
+import (
+	"context"
+	"internal/poll"
+	"os"
+	"runtime"
+	"syscall"
+)
+
+const (
+	readSyscallName     = "read"
+	readFromSyscallName = "recvfrom"
+	readMsgSyscallName  = "recvmsg"
+	writeSyscallName    = "write"
+	writeToSyscallName  = "sendto"
+	writeMsgSyscallName = "sendmsg"
+)
+
+func newFD(sysfd, family, sotype int, net string) (*netFD, error) {
+	ret := &netFD{
+		pfd: poll.FD{
+			Sysfd:         sysfd,
+			IsStream:      sotype == syscall.SOCK_STREAM,
+			ZeroReadIsEOF: sotype != syscall.SOCK_DGRAM && sotype != syscall.SOCK_RAW,
+		},
+		family: family,
+		sotype: sotype,
+		net:    net,
+	}
+	return ret, nil
+}
+
+func (fd *netFD) init() error {
+	return fd.pfd.Init(fd.net, true)
+}
+
+func (fd *netFD) name() string {
+	var ls, rs string
+	if fd.laddr != nil {
+		ls = fd.laddr.String()
+	}
+	if fd.raddr != nil {
+		rs = fd.raddr.String()
+	}
+	return fd.net + ":" + ls + "->" + rs
+}
+
+func (fd *netFD) connect(ctx context.Context, la, ra syscall.Sockaddr) (rsa syscall.Sockaddr, ret error) {
+	// Do not need to call fd.writeLock here,
+	// because fd is not yet accessible to user,
+	// so no concurrent operations are possible.
+	switch err := connectFunc(fd.pfd.Sysfd, ra); err {
+	case syscall.EINPROGRESS, syscall.EALREADY, syscall.EINTR:
+	case nil, syscall.EISCONN:
+		select {
+		case <-ctx.Done():
+			return nil, mapErr(ctx.Err())
+		default:
+		}
+		if err := fd.pfd.Init(fd.net, true); err != nil {
+			return nil, err
+		}
+		runtime.KeepAlive(fd)
+		return nil, nil
+	case syscall.EINVAL:
+		// On Solaris and illumos we can see EINVAL if the socket has
+		// already been accepted and closed by the server.  Treat this
+		// as a successful connection--writes to the socket will see
+		// EOF.  For details and a test case in C see
+		// https://golang.org/issue/6828.
+		if runtime.GOOS == "solaris" || runtime.GOOS == "illumos" {
+			return nil, nil
+		}
+		fallthrough
+	default:
+		return nil, os.NewSyscallError("connect", err)
+	}
+	if err := fd.pfd.Init(fd.net, true); err != nil {
+		return nil, err
+	}
+	if deadline, hasDeadline := ctx.Deadline(); hasDeadline {
+		fd.pfd.SetWriteDeadline(deadline)
+		defer fd.pfd.SetWriteDeadline(noDeadline)
+	}
+
+	// Start the "interrupter" goroutine, if this context might be canceled.
+	//
+	// The interrupter goroutine waits for the context to be done and
+	// interrupts the dial (by altering the fd's write deadline, which
+	// wakes up waitWrite).
+	ctxDone := ctx.Done()
+	if ctxDone != nil {
+		// Wait for the interrupter goroutine to exit before returning
+		// from connect.
+		done := make(chan struct{})
+		interruptRes := make(chan error)
+		defer func() {
+			close(done)
+			if ctxErr := <-interruptRes; ctxErr != nil && ret == nil {
+				// The interrupter goroutine called SetWriteDeadline,
+				// but the connect code below had returned from
+				// waitWrite already and did a successful connect (ret
+				// == nil). Because we've now poisoned the connection
+				// by making it unwritable, don't return a successful
+				// dial. This was issue 16523.
+				ret = mapErr(ctxErr)
+				fd.Close() // prevent a leak
+			}
+		}()
+		go func() {
+			select {
+			case <-ctxDone:
+				// Force the runtime's poller to immediately give up
+				// waiting for writability, unblocking waitWrite
+				// below.
+				fd.pfd.SetWriteDeadline(aLongTimeAgo)
+				testHookCanceledDial()
+				interruptRes <- ctx.Err()
+			case <-done:
+				interruptRes <- nil
+			}
+		}()
+	}
+
+	for {
+		// Performing multiple connect system calls on a
+		// non-blocking socket under Unix variants does not
+		// necessarily result in earlier errors being
+		// returned. Instead, once runtime-integrated network
+		// poller tells us that the socket is ready, get the
+		// SO_ERROR socket option to see if the connection
+		// succeeded or failed. See issue 7474 for further
+		// details.
+		if err := fd.pfd.WaitWrite(); err != nil {
+			select {
+			case <-ctxDone:
+				return nil, mapErr(ctx.Err())
+			default:
+			}
+			return nil, err
+		}
+		nerr, err := getsockoptIntFunc(fd.pfd.Sysfd, syscall.SOL_SOCKET, syscall.SO_ERROR)
+		if err != nil {
+			return nil, os.NewSyscallError("getsockopt", err)
+		}
+		switch err := syscall.Errno(nerr); err {
+		case syscall.EINPROGRESS, syscall.EALREADY, syscall.EINTR:
+		case syscall.EISCONN:
+			return nil, nil
+		case syscall.Errno(0):
+			// The runtime poller can wake us up spuriously;
+			// see issues 14548 and 19289. Check that we are
+			// really connected; if not, wait again.
+			if rsa, err := syscall.Getpeername(fd.pfd.Sysfd); err == nil {
+				return rsa, nil
+			}
+		default:
+			return nil, os.NewSyscallError("connect", err)
+		}
+		runtime.KeepAlive(fd)
+	}
+}
+
+func (fd *netFD) accept() (netfd *netFD, err error) {
+	d, rsa, errcall, err := fd.pfd.Accept()
+	if err != nil {
+		if errcall != "" {
+			err = wrapSyscallError(errcall, err)
+		}
+		return nil, err
+	}
+
+	if netfd, err = newFD(d, fd.family, fd.sotype, fd.net); err != nil {
+		poll.CloseFunc(d)
+		return nil, err
+	}
+	if err = netfd.init(); err != nil {
+		netfd.Close()
+		return nil, err
+	}
+	lsa, _ := syscall.Getsockname(netfd.pfd.Sysfd)
+	netfd.setAddr(netfd.addrFunc()(lsa), netfd.addrFunc()(rsa))
+	return netfd, nil
+}
+
+func (fd *netFD) dup() (f *os.File, err error) {
+	ns, call, err := fd.pfd.Dup()
+	if err != nil {
+		if call != "" {
+			err = os.NewSyscallError(call, err)
+		}
+		return nil, err
+	}
+
+	return os.NewFile(uintptr(ns), fd.name()), nil
+}
diff --git a/contrib/go/_std_1.18/src/net/file.go b/contrib/go/_std_1.19/src/net/file.go
index c13332c188..c13332c188 100644
--- a/contrib/go/_std_1.18/src/net/file.go
+++ b/contrib/go/_std_1.19/src/net/file.go
diff --git a/contrib/go/_std_1.19/src/net/file_unix.go b/contrib/go/_std_1.19/src/net/file_unix.go
new file mode 100644
index 0000000000..0df67db501
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/file_unix.go
@@ -0,0 +1,119 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix
+
+package net
+
+import (
+	"internal/poll"
+	"os"
+	"syscall"
+)
+
+func dupSocket(f *os.File) (int, error) {
+	s, call, err := poll.DupCloseOnExec(int(f.Fd()))
+	if err != nil {
+		if call != "" {
+			err = os.NewSyscallError(call, err)
+		}
+		return -1, err
+	}
+	if err := syscall.SetNonblock(s, true); err != nil {
+		poll.CloseFunc(s)
+		return -1, os.NewSyscallError("setnonblock", err)
+	}
+	return s, nil
+}
+
+func newFileFD(f *os.File) (*netFD, error) {
+	s, err := dupSocket(f)
+	if err != nil {
+		return nil, err
+	}
+	family := syscall.AF_UNSPEC
+	sotype, err := syscall.GetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_TYPE)
+	if err != nil {
+		poll.CloseFunc(s)
+		return nil, os.NewSyscallError("getsockopt", err)
+	}
+	lsa, _ := syscall.Getsockname(s)
+	rsa, _ := syscall.Getpeername(s)
+	switch lsa.(type) {
+	case *syscall.SockaddrInet4:
+		family = syscall.AF_INET
+	case *syscall.SockaddrInet6:
+		family = syscall.AF_INET6
+	case *syscall.SockaddrUnix:
+		family = syscall.AF_UNIX
+	default:
+		poll.CloseFunc(s)
+		return nil, syscall.EPROTONOSUPPORT
+	}
+	fd, err := newFD(s, family, sotype, "")
+	if err != nil {
+		poll.CloseFunc(s)
+		return nil, err
+	}
+	laddr := fd.addrFunc()(lsa)
+	raddr := fd.addrFunc()(rsa)
+	fd.net = laddr.Network()
+	if err := fd.init(); err != nil {
+		fd.Close()
+		return nil, err
+	}
+	fd.setAddr(laddr, raddr)
+	return fd, nil
+}
+
+func fileConn(f *os.File) (Conn, error) {
+	fd, err := newFileFD(f)
+	if err != nil {
+		return nil, err
+	}
+	switch fd.laddr.(type) {
+	case *TCPAddr:
+		return newTCPConn(fd), nil
+	case *UDPAddr:
+		return newUDPConn(fd), nil
+	case *IPAddr:
+		return newIPConn(fd), nil
+	case *UnixAddr:
+		return newUnixConn(fd), nil
+	}
+	fd.Close()
+	return nil, syscall.EINVAL
+}
+
+func fileListener(f *os.File) (Listener, error) {
+	fd, err := newFileFD(f)
+	if err != nil {
+		return nil, err
+	}
+	switch laddr := fd.laddr.(type) {
+	case *TCPAddr:
+		return &TCPListener{fd: fd}, nil
+	case *UnixAddr:
+		return &UnixListener{fd: fd, path: laddr.Name, unlink: false}, nil
+	}
+	fd.Close()
+	return nil, syscall.EINVAL
+}
+
+func filePacketConn(f *os.File) (PacketConn, error) {
+	fd, err := newFileFD(f)
+	if err != nil {
+		return nil, err
+	}
+	switch fd.laddr.(type) {
+	case *UDPAddr:
+		return newUDPConn(fd), nil
+	case *IPAddr:
+		return newIPConn(fd), nil
+	case *UnixAddr:
+		return newUnixConn(fd), nil
+	}
+	fd.Close()
+	return nil, syscall.EINVAL
+}
diff --git a/contrib/go/_std_1.18/src/net/hook.go b/contrib/go/_std_1.19/src/net/hook.go
index ea71803e22..ea71803e22 100644
--- a/contrib/go/_std_1.18/src/net/hook.go
+++ b/contrib/go/_std_1.19/src/net/hook.go
diff --git a/contrib/go/_std_1.19/src/net/hook_unix.go b/contrib/go/_std_1.19/src/net/hook_unix.go
new file mode 100644
index 0000000000..fa82c7e52b
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/hook_unix.go
@@ -0,0 +1,20 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm)
+
+package net
+
+import "syscall"
+
+var (
+	testHookDialChannel  = func() {} // for golang.org/issue/5349
+	testHookCanceledDial = func() {} // for golang.org/issue/16523
+
+	// Placeholders for socket system calls.
+	socketFunc        func(int, int, int) (int, error)  = syscall.Socket
+	connectFunc       func(int, syscall.Sockaddr) error = syscall.Connect
+	listenFunc        func(int, int) error              = syscall.Listen
+	getsockoptIntFunc func(int, int, int) (int, error)  = syscall.GetsockoptInt
+)
diff --git a/contrib/go/_std_1.18/src/net/hosts.go b/contrib/go/_std_1.19/src/net/hosts.go
index e604031920..e604031920 100644
--- a/contrib/go/_std_1.18/src/net/hosts.go
+++ b/contrib/go/_std_1.19/src/net/hosts.go
diff --git a/contrib/go/_std_1.19/src/net/http/client.go b/contrib/go/_std_1.19/src/net/http/client.go
new file mode 100644
index 0000000000..992817c0f5
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/http/client.go
@@ -0,0 +1,1023 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// HTTP client. See RFC 7230 through 7235.
+//
+// This is the high-level Client interface.
+// The low-level implementation is in transport.go.
+
+package http
+
+import (
+	"context"
+	"crypto/tls"
+	"encoding/base64"
+	"errors"
+	"fmt"
+	"io"
+	"log"
+	"net/http/internal/ascii"
+	"net/url"
+	"reflect"
+	"sort"
+	"strings"
+	"sync"
+	"time"
+)
+
+// A Client is an HTTP client. Its zero value (DefaultClient) is a
+// usable client that uses DefaultTransport.
+//
+// The Client's Transport typically has internal state (cached TCP
+// connections), so Clients should be reused instead of created as
+// needed. Clients are safe for concurrent use by multiple goroutines.
+//
+// A Client is higher-level than a RoundTripper (such as Transport)
+// and additionally handles HTTP details such as cookies and
+// redirects.
+//
+// When following redirects, the Client will forward all headers set on the
+// initial Request except:
+//
+// • when forwarding sensitive headers like "Authorization",
+// "WWW-Authenticate", and "Cookie" to untrusted targets.
+// These headers will be ignored when following a redirect to a domain
+// that is not a subdomain match or exact match of the initial domain.
+// For example, a redirect from "foo.com" to either "foo.com" or "sub.foo.com"
+// will forward the sensitive headers, but a redirect to "bar.com" will not.
+//
+// • when forwarding the "Cookie" header with a non-nil cookie Jar.
+// Since each redirect may mutate the state of the cookie jar,
+// a redirect may possibly alter a cookie set in the initial request.
+// When forwarding the "Cookie" header, any mutated cookies will be omitted,
+// with the expectation that the Jar will insert those mutated cookies
+// with the updated values (assuming the origin matches).
+// If Jar is nil, the initial cookies are forwarded without change.
+type Client struct {
+	// Transport specifies the mechanism by which individual
+	// HTTP requests are made.
+	// If nil, DefaultTransport is used.
+	Transport RoundTripper
+
+	// CheckRedirect specifies the policy for handling redirects.
+	// If CheckRedirect is not nil, the client calls it before
+	// following an HTTP redirect. The arguments req and via are
+	// the upcoming request and the requests made already, oldest
+	// first. If CheckRedirect returns an error, the Client's Get
+	// method returns both the previous Response (with its Body
+	// closed) and CheckRedirect's error (wrapped in a url.Error)
+	// instead of issuing the Request req.
+	// As a special case, if CheckRedirect returns ErrUseLastResponse,
+	// then the most recent response is returned with its body
+	// unclosed, along with a nil error.
+	//
+	// If CheckRedirect is nil, the Client uses its default policy,
+	// which is to stop after 10 consecutive requests.
+	CheckRedirect func(req *Request, via []*Request) error
+
+	// Jar specifies the cookie jar.
+	//
+	// The Jar is used to insert relevant cookies into every
+	// outbound Request and is updated with the cookie values
+	// of every inbound Response. The Jar is consulted for every
+	// redirect that the Client follows.
+	//
+	// If Jar is nil, cookies are only sent if they are explicitly
+	// set on the Request.
+	Jar CookieJar
+
+	// Timeout specifies a time limit for requests made by this
+	// Client. The timeout includes connection time, any
+	// redirects, and reading the response body. The timer remains
+	// running after Get, Head, Post, or Do return and will
+	// interrupt reading of the Response.Body.
+	//
+	// A Timeout of zero means no timeout.
+	//
+	// The Client cancels requests to the underlying Transport
+	// as if the Request's Context ended.
+	//
+	// For compatibility, the Client will also use the deprecated
+	// CancelRequest method on Transport if found. New
+	// RoundTripper implementations should use the Request's Context
+	// for cancellation instead of implementing CancelRequest.
+	Timeout time.Duration
+}
+
+// DefaultClient is the default Client and is used by Get, Head, and Post.
+var DefaultClient = &Client{}
+
+// RoundTripper is an interface representing the ability to execute a
+// single HTTP transaction, obtaining the Response for a given Request.
+//
+// A RoundTripper must be safe for concurrent use by multiple
+// goroutines.
+type RoundTripper interface {
+	// RoundTrip executes a single HTTP transaction, returning
+	// a Response for the provided Request.
+	//
+	// RoundTrip should not attempt to interpret the response. In
+	// particular, RoundTrip must return err == nil if it obtained
+	// a response, regardless of the response's HTTP status code.
+	// A non-nil err should be reserved for failure to obtain a
+	// response. Similarly, RoundTrip should not attempt to
+	// handle higher-level protocol details such as redirects,
+	// authentication, or cookies.
+	//
+	// RoundTrip should not modify the request, except for
+	// consuming and closing the Request's Body. RoundTrip may
+	// read fields of the request in a separate goroutine. Callers
+	// should not mutate or reuse the request until the Response's
+	// Body has been closed.
+	//
+	// RoundTrip must always close the body, including on errors,
+	// but depending on the implementation may do so in a separate
+	// goroutine even after RoundTrip returns. This means that
+	// callers wanting to reuse the body for subsequent requests
+	// must arrange to wait for the Close call before doing so.
+	//
+	// The Request's URL and Header fields must be initialized.
+	RoundTrip(*Request) (*Response, error)
+}
+
+// refererForURL returns a referer without any authentication info or
+// an empty string if lastReq scheme is https and newReq scheme is http.
+func refererForURL(lastReq, newReq *url.URL) string {
+	// https://tools.ietf.org/html/rfc7231#section-5.5.2
+	//   "Clients SHOULD NOT include a Referer header field in a
+	//    (non-secure) HTTP request if the referring page was
+	//    transferred with a secure protocol."
+	if lastReq.Scheme == "https" && newReq.Scheme == "http" {
+		return ""
+	}
+	referer := lastReq.String()
+	if lastReq.User != nil {
+		// This is not very efficient, but is the best we can
+		// do without:
+		// - introducing a new method on URL
+		// - creating a race condition
+		// - copying the URL struct manually, which would cause
+		//   maintenance problems down the line
+		auth := lastReq.User.String() + "@"
+		referer = strings.Replace(referer, auth, "", 1)
+	}
+	return referer
+}
+
+// didTimeout is non-nil only if err != nil.
+func (c *Client) send(req *Request, deadline time.Time) (resp *Response, didTimeout func() bool, err error) {
+	if c.Jar != nil {
+		for _, cookie := range c.Jar.Cookies(req.URL) {
+			req.AddCookie(cookie)
+		}
+	}
+	resp, didTimeout, err = send(req, c.transport(), deadline)
+	if err != nil {
+		return nil, didTimeout, err
+	}
+	if c.Jar != nil {
+		if rc := resp.Cookies(); len(rc) > 0 {
+			c.Jar.SetCookies(req.URL, rc)
+		}
+	}
+	return resp, nil, nil
+}
+
+func (c *Client) deadline() time.Time {
+	if c.Timeout > 0 {
+		return time.Now().Add(c.Timeout)
+	}
+	return time.Time{}
+}
+
+func (c *Client) transport() RoundTripper {
+	if c.Transport != nil {
+		return c.Transport
+	}
+	return DefaultTransport
+}
+
+// send issues an HTTP request.
+// Caller should close resp.Body when done reading from it.
+func send(ireq *Request, rt RoundTripper, deadline time.Time) (resp *Response, didTimeout func() bool, err error) {
+	req := ireq // req is either the original request, or a modified fork
+
+	if rt == nil {
+		req.closeBody()
+		return nil, alwaysFalse, errors.New("http: no Client.Transport or DefaultTransport")
+	}
+
+	if req.URL == nil {
+		req.closeBody()
+		return nil, alwaysFalse, errors.New("http: nil Request.URL")
+	}
+
+	if req.RequestURI != "" {
+		req.closeBody()
+		return nil, alwaysFalse, errors.New("http: Request.RequestURI can't be set in client requests")
+	}
+
+	// forkReq forks req into a shallow clone of ireq the first
+	// time it's called.
+	forkReq := func() {
+		if ireq == req {
+			req = new(Request)
+			*req = *ireq // shallow clone
+		}
+	}
+
+	// Most the callers of send (Get, Post, et al) don't need
+	// Headers, leaving it uninitialized. We guarantee to the
+	// Transport that this has been initialized, though.
+	if req.Header == nil {
+		forkReq()
+		req.Header = make(Header)
+	}
+
+	if u := req.URL.User; u != nil && req.Header.Get("Authorization") == "" {
+		username := u.Username()
+		password, _ := u.Password()
+		forkReq()
+		req.Header = cloneOrMakeHeader(ireq.Header)
+		req.Header.Set("Authorization", "Basic "+basicAuth(username, password))
+	}
+
+	if !deadline.IsZero() {
+		forkReq()
+	}
+	stopTimer, didTimeout := setRequestCancel(req, rt, deadline)
+
+	resp, err = rt.RoundTrip(req)
+	if err != nil {
+		stopTimer()
+		if resp != nil {
+			log.Printf("RoundTripper returned a response & error; ignoring response")
+		}
+		if tlsErr, ok := err.(tls.RecordHeaderError); ok {
+			// If we get a bad TLS record header, check to see if the
+			// response looks like HTTP and give a more helpful error.
+			// See golang.org/issue/11111.
+			if string(tlsErr.RecordHeader[:]) == "HTTP/" {
+				err = errors.New("http: server gave HTTP response to HTTPS client")
+			}
+		}
+		return nil, didTimeout, err
+	}
+	if resp == nil {
+		return nil, didTimeout, fmt.Errorf("http: RoundTripper implementation (%T) returned a nil *Response with a nil error", rt)
+	}
+	if resp.Body == nil {
+		// The documentation on the Body field says “The http Client and Transport
+		// guarantee that Body is always non-nil, even on responses without a body
+		// or responses with a zero-length body.” Unfortunately, we didn't document
+		// that same constraint for arbitrary RoundTripper implementations, and
+		// RoundTripper implementations in the wild (mostly in tests) assume that
+		// they can use a nil Body to mean an empty one (similar to Request.Body).
+		// (See https://golang.org/issue/38095.)
+		//
+		// If the ContentLength allows the Body to be empty, fill in an empty one
+		// here to ensure that it is non-nil.
+		if resp.ContentLength > 0 && req.Method != "HEAD" {
+			return nil, didTimeout, fmt.Errorf("http: RoundTripper implementation (%T) returned a *Response with content length %d but a nil Body", rt, resp.ContentLength)
+		}
+		resp.Body = io.NopCloser(strings.NewReader(""))
+	}
+	if !deadline.IsZero() {
+		resp.Body = &cancelTimerBody{
+			stop:          stopTimer,
+			rc:            resp.Body,
+			reqDidTimeout: didTimeout,
+		}
+	}
+	return resp, nil, nil
+}
+
+// timeBeforeContextDeadline reports whether the non-zero Time t is
+// before ctx's deadline, if any. If ctx does not have a deadline, it
+// always reports true (the deadline is considered infinite).
+func timeBeforeContextDeadline(t time.Time, ctx context.Context) bool {
+	d, ok := ctx.Deadline()
+	if !ok {
+		return true
+	}
+	return t.Before(d)
+}
+
+// knownRoundTripperImpl reports whether rt is a RoundTripper that's
+// maintained by the Go team and known to implement the latest
+// optional semantics (notably contexts). The Request is used
+// to check whether this particular request is using an alternate protocol,
+// in which case we need to check the RoundTripper for that protocol.
+func knownRoundTripperImpl(rt RoundTripper, req *Request) bool {
+	switch t := rt.(type) {
+	case *Transport:
+		if altRT := t.alternateRoundTripper(req); altRT != nil {
+			return knownRoundTripperImpl(altRT, req)
+		}
+		return true
+	case *http2Transport, http2noDialH2RoundTripper:
+		return true
+	}
+	// There's a very minor chance of a false positive with this.
+	// Instead of detecting our golang.org/x/net/http2.Transport,
+	// it might detect a Transport type in a different http2
+	// package. But I know of none, and the only problem would be
+	// some temporarily leaked goroutines if the transport didn't
+	// support contexts. So this is a good enough heuristic:
+	if reflect.TypeOf(rt).String() == "*http2.Transport" {
+		return true
+	}
+	return false
+}
+
+// setRequestCancel sets req.Cancel and adds a deadline context to req
+// if deadline is non-zero. The RoundTripper's type is used to
+// determine whether the legacy CancelRequest behavior should be used.
+//
+// As background, there are three ways to cancel a request:
+// First was Transport.CancelRequest. (deprecated)
+// Second was Request.Cancel.
+// Third was Request.Context.
+// This function populates the second and third, and uses the first if it really needs to.
+func setRequestCancel(req *Request, rt RoundTripper, deadline time.Time) (stopTimer func(), didTimeout func() bool) {
+	if deadline.IsZero() {
+		return nop, alwaysFalse
+	}
+	knownTransport := knownRoundTripperImpl(rt, req)
+	oldCtx := req.Context()
+
+	if req.Cancel == nil && knownTransport {
+		// If they already had a Request.Context that's
+		// expiring sooner, do nothing:
+		if !timeBeforeContextDeadline(deadline, oldCtx) {
+			return nop, alwaysFalse
+		}
+
+		var cancelCtx func()
+		req.ctx, cancelCtx = context.WithDeadline(oldCtx, deadline)
+		return cancelCtx, func() bool { return time.Now().After(deadline) }
+	}
+	initialReqCancel := req.Cancel // the user's original Request.Cancel, if any
+
+	var cancelCtx func()
+	if oldCtx := req.Context(); timeBeforeContextDeadline(deadline, oldCtx) {
+		req.ctx, cancelCtx = context.WithDeadline(oldCtx, deadline)
+	}
+
+	cancel := make(chan struct{})
+	req.Cancel = cancel
+
+	doCancel := func() {
+		// The second way in the func comment above:
+		close(cancel)
+		// The first way, used only for RoundTripper
+		// implementations written before Go 1.5 or Go 1.6.
+		type canceler interface{ CancelRequest(*Request) }
+		if v, ok := rt.(canceler); ok {
+			v.CancelRequest(req)
+		}
+	}
+
+	stopTimerCh := make(chan struct{})
+	var once sync.Once
+	stopTimer = func() {
+		once.Do(func() {
+			close(stopTimerCh)
+			if cancelCtx != nil {
+				cancelCtx()
+			}
+		})
+	}
+
+	timer := time.NewTimer(time.Until(deadline))
+	var timedOut atomicBool
+
+	go func() {
+		select {
+		case <-initialReqCancel:
+			doCancel()
+			timer.Stop()
+		case <-timer.C:
+			timedOut.setTrue()
+			doCancel()
+		case <-stopTimerCh:
+			timer.Stop()
+		}
+	}()
+
+	return stopTimer, timedOut.isSet
+}
+
+// See 2 (end of page 4) https://www.ietf.org/rfc/rfc2617.txt
+// "To receive authorization, the client sends the userid and password,
+// separated by a single colon (":") character, within a base64
+// encoded string in the credentials."
+// It is not meant to be urlencoded.
+func basicAuth(username, password string) string {
+	auth := username + ":" + password
+	return base64.StdEncoding.EncodeToString([]byte(auth))
+}
+
+// Get issues a GET to the specified URL. If the response is one of
+// the following redirect codes, Get follows the redirect, up to a
+// maximum of 10 redirects:
+//
+//	301 (Moved Permanently)
+//	302 (Found)
+//	303 (See Other)
+//	307 (Temporary Redirect)
+//	308 (Permanent Redirect)
+//
+// An error is returned if there were too many redirects or if there
+// was an HTTP protocol error. A non-2xx response doesn't cause an
+// error. Any returned error will be of type *url.Error. The url.Error
+// value's Timeout method will report true if the request timed out.
+//
+// When err is nil, resp always contains a non-nil resp.Body.
+// Caller should close resp.Body when done reading from it.
+//
+// Get is a wrapper around DefaultClient.Get.
+//
+// To make a request with custom headers, use NewRequest and
+// DefaultClient.Do.
+//
+// To make a request with a specified context.Context, use NewRequestWithContext
+// and DefaultClient.Do.
+func Get(url string) (resp *Response, err error) {
+	return DefaultClient.Get(url)
+}
+
+// Get issues a GET to the specified URL. If the response is one of the
+// following redirect codes, Get follows the redirect after calling the
+// Client's CheckRedirect function:
+//
+//	301 (Moved Permanently)
+//	302 (Found)
+//	303 (See Other)
+//	307 (Temporary Redirect)
+//	308 (Permanent Redirect)
+//
+// An error is returned if the Client's CheckRedirect function fails
+// or if there was an HTTP protocol error. A non-2xx response doesn't
+// cause an error. Any returned error will be of type *url.Error. The
+// url.Error value's Timeout method will report true if the request
+// timed out.
+//
+// When err is nil, resp always contains a non-nil resp.Body.
+// Caller should close resp.Body when done reading from it.
+//
+// To make a request with custom headers, use NewRequest and Client.Do.
+//
+// To make a request with a specified context.Context, use NewRequestWithContext
+// and Client.Do.
+func (c *Client) Get(url string) (resp *Response, err error) {
+	req, err := NewRequest("GET", url, nil)
+	if err != nil {
+		return nil, err
+	}
+	return c.Do(req)
+}
+
+func alwaysFalse() bool { return false }
+
+// ErrUseLastResponse can be returned by Client.CheckRedirect hooks to
+// control how redirects are processed. If returned, the next request
+// is not sent and the most recent response is returned with its body
+// unclosed.
+var ErrUseLastResponse = errors.New("net/http: use last response")
+
+// checkRedirect calls either the user's configured CheckRedirect
+// function, or the default.
+func (c *Client) checkRedirect(req *Request, via []*Request) error {
+	fn := c.CheckRedirect
+	if fn == nil {
+		fn = defaultCheckRedirect
+	}
+	return fn(req, via)
+}
+
+// redirectBehavior describes what should happen when the
+// client encounters a 3xx status code from the server
+func redirectBehavior(reqMethod string, resp *Response, ireq *Request) (redirectMethod string, shouldRedirect, includeBody bool) {
+	switch resp.StatusCode {
+	case 301, 302, 303:
+		redirectMethod = reqMethod
+		shouldRedirect = true
+		includeBody = false
+
+		// RFC 2616 allowed automatic redirection only with GET and
+		// HEAD requests. RFC 7231 lifts this restriction, but we still
+		// restrict other methods to GET to maintain compatibility.
+		// See Issue 18570.
+		if reqMethod != "GET" && reqMethod != "HEAD" {
+			redirectMethod = "GET"
+		}
+	case 307, 308:
+		redirectMethod = reqMethod
+		shouldRedirect = true
+		includeBody = true
+
+		if ireq.GetBody == nil && ireq.outgoingLength() != 0 {
+			// We had a request body, and 307/308 require
+			// re-sending it, but GetBody is not defined. So just
+			// return this response to the user instead of an
+			// error, like we did in Go 1.7 and earlier.
+			shouldRedirect = false
+		}
+	}
+	return redirectMethod, shouldRedirect, includeBody
+}
+
+// urlErrorOp returns the (*url.Error).Op value to use for the
+// provided (*Request).Method value.
+func urlErrorOp(method string) string {
+	if method == "" {
+		return "Get"
+	}
+	if lowerMethod, ok := ascii.ToLower(method); ok {
+		return method[:1] + lowerMethod[1:]
+	}
+	return method
+}
+
+// Do sends an HTTP request and returns an HTTP response, following
+// policy (such as redirects, cookies, auth) as configured on the
+// client.
+//
+// An error is returned if caused by client policy (such as
+// CheckRedirect), or failure to speak HTTP (such as a network
+// connectivity problem). A non-2xx status code doesn't cause an
+// error.
+//
+// If the returned error is nil, the Response will contain a non-nil
+// Body which the user is expected to close. If the Body is not both
+// read to EOF and closed, the Client's underlying RoundTripper
+// (typically Transport) may not be able to re-use a persistent TCP
+// connection to the server for a subsequent "keep-alive" request.
+//
+// The request Body, if non-nil, will be closed by the underlying
+// Transport, even on errors.
+//
+// On error, any Response can be ignored. A non-nil Response with a
+// non-nil error only occurs when CheckRedirect fails, and even then
+// the returned Response.Body is already closed.
+//
+// Generally Get, Post, or PostForm will be used instead of Do.
+//
+// If the server replies with a redirect, the Client first uses the
+// CheckRedirect function to determine whether the redirect should be
+// followed. If permitted, a 301, 302, or 303 redirect causes
+// subsequent requests to use HTTP method GET
+// (or HEAD if the original request was HEAD), with no body.
+// A 307 or 308 redirect preserves the original HTTP method and body,
+// provided that the Request.GetBody function is defined.
+// The NewRequest function automatically sets GetBody for common
+// standard library body types.
+//
+// Any returned error will be of type *url.Error. The url.Error
+// value's Timeout method will report true if the request timed out.
+func (c *Client) Do(req *Request) (*Response, error) {
+	return c.do(req)
+}
+
+var testHookClientDoResult func(retres *Response, reterr error)
+
+func (c *Client) do(req *Request) (retres *Response, reterr error) {
+	if testHookClientDoResult != nil {
+		defer func() { testHookClientDoResult(retres, reterr) }()
+	}
+	if req.URL == nil {
+		req.closeBody()
+		return nil, &url.Error{
+			Op:  urlErrorOp(req.Method),
+			Err: errors.New("http: nil Request.URL"),
+		}
+	}
+
+	var (
+		deadline      = c.deadline()
+		reqs          []*Request
+		resp          *Response
+		copyHeaders   = c.makeHeadersCopier(req)
+		reqBodyClosed = false // have we closed the current req.Body?
+
+		// Redirect behavior:
+		redirectMethod string
+		includeBody    bool
+	)
+	uerr := func(err error) error {
+		// the body may have been closed already by c.send()
+		if !reqBodyClosed {
+			req.closeBody()
+		}
+		var urlStr string
+		if resp != nil && resp.Request != nil {
+			urlStr = stripPassword(resp.Request.URL)
+		} else {
+			urlStr = stripPassword(req.URL)
+		}
+		return &url.Error{
+			Op:  urlErrorOp(reqs[0].Method),
+			URL: urlStr,
+			Err: err,
+		}
+	}
+	for {
+		// For all but the first request, create the next
+		// request hop and replace req.
+		if len(reqs) > 0 {
+			loc := resp.Header.Get("Location")
+			if loc == "" {
+				// While most 3xx responses include a Location, it is not
+				// required and 3xx responses without a Location have been
+				// observed in the wild. See issues #17773 and #49281.
+				return resp, nil
+			}
+			u, err := req.URL.Parse(loc)
+			if err != nil {
+				resp.closeBody()
+				return nil, uerr(fmt.Errorf("failed to parse Location header %q: %v", loc, err))
+			}
+			host := ""
+			if req.Host != "" && req.Host != req.URL.Host {
+				// If the caller specified a custom Host header and the
+				// redirect location is relative, preserve the Host header
+				// through the redirect. See issue #22233.
+				if u, _ := url.Parse(loc); u != nil && !u.IsAbs() {
+					host = req.Host
+				}
+			}
+			ireq := reqs[0]
+			req = &Request{
+				Method:   redirectMethod,
+				Response: resp,
+				URL:      u,
+				Header:   make(Header),
+				Host:     host,
+				Cancel:   ireq.Cancel,
+				ctx:      ireq.ctx,
+			}
+			if includeBody && ireq.GetBody != nil {
+				req.Body, err = ireq.GetBody()
+				if err != nil {
+					resp.closeBody()
+					return nil, uerr(err)
+				}
+				req.ContentLength = ireq.ContentLength
+			}
+
+			// Copy original headers before setting the Referer,
+			// in case the user set Referer on their first request.
+			// If they really want to override, they can do it in
+			// their CheckRedirect func.
+			copyHeaders(req)
+
+			// Add the Referer header from the most recent
+			// request URL to the new one, if it's not https->http:
+			if ref := refererForURL(reqs[len(reqs)-1].URL, req.URL); ref != "" {
+				req.Header.Set("Referer", ref)
+			}
+			err = c.checkRedirect(req, reqs)
+
+			// Sentinel error to let users select the
+			// previous response, without closing its
+			// body. See Issue 10069.
+			if err == ErrUseLastResponse {
+				return resp, nil
+			}
+
+			// Close the previous response's body. But
+			// read at least some of the body so if it's
+			// small the underlying TCP connection will be
+			// re-used. No need to check for errors: if it
+			// fails, the Transport won't reuse it anyway.
+			const maxBodySlurpSize = 2 << 10
+			if resp.ContentLength == -1 || resp.ContentLength <= maxBodySlurpSize {
+				io.CopyN(io.Discard, resp.Body, maxBodySlurpSize)
+			}
+			resp.Body.Close()
+
+			if err != nil {
+				// Special case for Go 1 compatibility: return both the response
+				// and an error if the CheckRedirect function failed.
+				// See https://golang.org/issue/3795
+				// The resp.Body has already been closed.
+				ue := uerr(err)
+				ue.(*url.Error).URL = loc
+				return resp, ue
+			}
+		}
+
+		reqs = append(reqs, req)
+		var err error
+		var didTimeout func() bool
+		if resp, didTimeout, err = c.send(req, deadline); err != nil {
+			// c.send() always closes req.Body
+			reqBodyClosed = true
+			if !deadline.IsZero() && didTimeout() {
+				err = &httpError{
+					err:     err.Error() + " (Client.Timeout exceeded while awaiting headers)",
+					timeout: true,
+				}
+			}
+			return nil, uerr(err)
+		}
+
+		var shouldRedirect bool
+		redirectMethod, shouldRedirect, includeBody = redirectBehavior(req.Method, resp, reqs[0])
+		if !shouldRedirect {
+			return resp, nil
+		}
+
+		req.closeBody()
+	}
+}
+
+// makeHeadersCopier makes a function that copies headers from the
+// initial Request, ireq. For every redirect, this function must be called
+// so that it can copy headers into the upcoming Request.
+func (c *Client) makeHeadersCopier(ireq *Request) func(*Request) {
+	// The headers to copy are from the very initial request.
+	// We use a closured callback to keep a reference to these original headers.
+	var (
+		ireqhdr  = cloneOrMakeHeader(ireq.Header)
+		icookies map[string][]*Cookie
+	)
+	if c.Jar != nil && ireq.Header.Get("Cookie") != "" {
+		icookies = make(map[string][]*Cookie)
+		for _, c := range ireq.Cookies() {
+			icookies[c.Name] = append(icookies[c.Name], c)
+		}
+	}
+
+	preq := ireq // The previous request
+	return func(req *Request) {
+		// If Jar is present and there was some initial cookies provided
+		// via the request header, then we may need to alter the initial
+		// cookies as we follow redirects since each redirect may end up
+		// modifying a pre-existing cookie.
+		//
+		// Since cookies already set in the request header do not contain
+		// information about the original domain and path, the logic below
+		// assumes any new set cookies override the original cookie
+		// regardless of domain or path.
+		//
+		// See https://golang.org/issue/17494
+		if c.Jar != nil && icookies != nil {
+			var changed bool
+			resp := req.Response // The response that caused the upcoming redirect
+			for _, c := range resp.Cookies() {
+				if _, ok := icookies[c.Name]; ok {
+					delete(icookies, c.Name)
+					changed = true
+				}
+			}
+			if changed {
+				ireqhdr.Del("Cookie")
+				var ss []string
+				for _, cs := range icookies {
+					for _, c := range cs {
+						ss = append(ss, c.Name+"="+c.Value)
+					}
+				}
+				sort.Strings(ss) // Ensure deterministic headers
+				ireqhdr.Set("Cookie", strings.Join(ss, "; "))
+			}
+		}
+
+		// Copy the initial request's Header values
+		// (at least the safe ones).
+		for k, vv := range ireqhdr {
+			if shouldCopyHeaderOnRedirect(k, preq.URL, req.URL) {
+				req.Header[k] = vv
+			}
+		}
+
+		preq = req // Update previous Request with the current request
+	}
+}
+
+func defaultCheckRedirect(req *Request, via []*Request) error {
+	if len(via) >= 10 {
+		return errors.New("stopped after 10 redirects")
+	}
+	return nil
+}
+
+// Post issues a POST to the specified URL.
+//
+// Caller should close resp.Body when done reading from it.
+//
+// If the provided body is an io.Closer, it is closed after the
+// request.
+//
+// Post is a wrapper around DefaultClient.Post.
+//
+// To set custom headers, use NewRequest and DefaultClient.Do.
+//
+// See the Client.Do method documentation for details on how redirects
+// are handled.
+//
+// To make a request with a specified context.Context, use NewRequestWithContext
+// and DefaultClient.Do.
+func Post(url, contentType string, body io.Reader) (resp *Response, err error) {
+	return DefaultClient.Post(url, contentType, body)
+}
+
+// Post issues a POST to the specified URL.
+//
+// Caller should close resp.Body when done reading from it.
+//
+// If the provided body is an io.Closer, it is closed after the
+// request.
+//
+// To set custom headers, use NewRequest and Client.Do.
+//
+// To make a request with a specified context.Context, use NewRequestWithContext
+// and Client.Do.
+//
+// See the Client.Do method documentation for details on how redirects
+// are handled.
+func (c *Client) Post(url, contentType string, body io.Reader) (resp *Response, err error) {
+	req, err := NewRequest("POST", url, body)
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Set("Content-Type", contentType)
+	return c.Do(req)
+}
+
+// PostForm issues a POST to the specified URL, with data's keys and
+// values URL-encoded as the request body.
+//
+// The Content-Type header is set to application/x-www-form-urlencoded.
+// To set other headers, use NewRequest and DefaultClient.Do.
+//
+// When err is nil, resp always contains a non-nil resp.Body.
+// Caller should close resp.Body when done reading from it.
+//
+// PostForm is a wrapper around DefaultClient.PostForm.
+//
+// See the Client.Do method documentation for details on how redirects
+// are handled.
+//
+// To make a request with a specified context.Context, use NewRequestWithContext
+// and DefaultClient.Do.
+func PostForm(url string, data url.Values) (resp *Response, err error) {
+	return DefaultClient.PostForm(url, data)
+}
+
+// PostForm issues a POST to the specified URL,
+// with data's keys and values URL-encoded as the request body.
+//
+// The Content-Type header is set to application/x-www-form-urlencoded.
+// To set other headers, use NewRequest and Client.Do.
+//
+// When err is nil, resp always contains a non-nil resp.Body.
+// Caller should close resp.Body when done reading from it.
+//
+// See the Client.Do method documentation for details on how redirects
+// are handled.
+//
+// To make a request with a specified context.Context, use NewRequestWithContext
+// and Client.Do.
+func (c *Client) PostForm(url string, data url.Values) (resp *Response, err error) {
+	return c.Post(url, "application/x-www-form-urlencoded", strings.NewReader(data.Encode()))
+}
+
+// Head issues a HEAD to the specified URL. If the response is one of
+// the following redirect codes, Head follows the redirect, up to a
+// maximum of 10 redirects:
+//
+//	301 (Moved Permanently)
+//	302 (Found)
+//	303 (See Other)
+//	307 (Temporary Redirect)
+//	308 (Permanent Redirect)
+//
+// Head is a wrapper around DefaultClient.Head.
+//
+// To make a request with a specified context.Context, use NewRequestWithContext
+// and DefaultClient.Do.
+func Head(url string) (resp *Response, err error) {
+	return DefaultClient.Head(url)
+}
+
+// Head issues a HEAD to the specified URL. If the response is one of the
+// following redirect codes, Head follows the redirect after calling the
+// Client's CheckRedirect function:
+//
+//	301 (Moved Permanently)
+//	302 (Found)
+//	303 (See Other)
+//	307 (Temporary Redirect)
+//	308 (Permanent Redirect)
+//
+// To make a request with a specified context.Context, use NewRequestWithContext
+// and Client.Do.
+func (c *Client) Head(url string) (resp *Response, err error) {
+	req, err := NewRequest("HEAD", url, nil)
+	if err != nil {
+		return nil, err
+	}
+	return c.Do(req)
+}
+
+// CloseIdleConnections closes any connections on its Transport which
+// were previously connected from previous requests but are now
+// sitting idle in a "keep-alive" state. It does not interrupt any
+// connections currently in use.
+//
+// If the Client's Transport does not have a CloseIdleConnections method
+// then this method does nothing.
+func (c *Client) CloseIdleConnections() {
+	type closeIdler interface {
+		CloseIdleConnections()
+	}
+	if tr, ok := c.transport().(closeIdler); ok {
+		tr.CloseIdleConnections()
+	}
+}
+
+// cancelTimerBody is an io.ReadCloser that wraps rc with two features:
+//  1. On Read error or close, the stop func is called.
+//  2. On Read failure, if reqDidTimeout is true, the error is wrapped and
+//     marked as net.Error that hit its timeout.
+type cancelTimerBody struct {
+	stop          func() // stops the time.Timer waiting to cancel the request
+	rc            io.ReadCloser
+	reqDidTimeout func() bool
+}
+
+func (b *cancelTimerBody) Read(p []byte) (n int, err error) {
+	n, err = b.rc.Read(p)
+	if err == nil {
+		return n, nil
+	}
+	if err == io.EOF {
+		return n, err
+	}
+	if b.reqDidTimeout() {
+		err = &httpError{
+			err:     err.Error() + " (Client.Timeout or context cancellation while reading body)",
+			timeout: true,
+		}
+	}
+	return n, err
+}
+
+func (b *cancelTimerBody) Close() error {
+	err := b.rc.Close()
+	b.stop()
+	return err
+}
+
+func shouldCopyHeaderOnRedirect(headerKey string, initial, dest *url.URL) bool {
+	switch CanonicalHeaderKey(headerKey) {
+	case "Authorization", "Www-Authenticate", "Cookie", "Cookie2":
+		// Permit sending auth/cookie headers from "foo.com"
+		// to "sub.foo.com".
+
+		// Note that we don't send all cookies to subdomains
+		// automatically. This function is only used for
+		// Cookies set explicitly on the initial outgoing
+		// client request. Cookies automatically added via the
+		// CookieJar mechanism continue to follow each
+		// cookie's scope as set by Set-Cookie. But for
+		// outgoing requests with the Cookie header set
+		// directly, we don't know their scope, so we assume
+		// it's for *.domain.com.
+
+		ihost := canonicalAddr(initial)
+		dhost := canonicalAddr(dest)
+		return isDomainOrSubdomain(dhost, ihost)
+	}
+	// All other headers are copied:
+	return true
+}
+
+// isDomainOrSubdomain reports whether sub is a subdomain (or exact
+// match) of the parent domain.
+//
+// Both domains must already be in canonical form.
+func isDomainOrSubdomain(sub, parent string) bool {
+	if sub == parent {
+		return true
+	}
+	// If sub is "foo.example.com" and parent is "example.com",
+	// that means sub must end in "."+parent.
+	// Do it without allocating.
+	if !strings.HasSuffix(sub, parent) {
+		return false
+	}
+	return sub[len(sub)-len(parent)-1] == '.'
+}
+
+func stripPassword(u *url.URL) string {
+	_, passSet := u.User.Password()
+	if passSet {
+		return strings.Replace(u.String(), u.User.String()+"@", u.User.Username()+":***@", 1)
+	}
+	return u.String()
+}
diff --git a/contrib/go/_std_1.18/src/net/http/clone.go b/contrib/go/_std_1.19/src/net/http/clone.go
index 3a3375bff7..3a3375bff7 100644
--- a/contrib/go/_std_1.18/src/net/http/clone.go
+++ b/contrib/go/_std_1.19/src/net/http/clone.go
diff --git a/contrib/go/_std_1.19/src/net/http/cookie.go b/contrib/go/_std_1.19/src/net/http/cookie.go
new file mode 100644
index 0000000000..9cb0804f8f
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/http/cookie.go
@@ -0,0 +1,466 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package http
+
+import (
+	"errors"
+	"fmt"
+	"log"
+	"net"
+	"net/http/internal/ascii"
+	"net/textproto"
+	"strconv"
+	"strings"
+	"time"
+)
+
+// A Cookie represents an HTTP cookie as sent in the Set-Cookie header of an
+// HTTP response or the Cookie header of an HTTP request.
+//
+// See https://tools.ietf.org/html/rfc6265 for details.
+type Cookie struct {
+	Name  string
+	Value string
+
+	Path       string    // optional
+	Domain     string    // optional
+	Expires    time.Time // optional
+	RawExpires string    // for reading cookies only
+
+	// MaxAge=0 means no 'Max-Age' attribute specified.
+	// MaxAge<0 means delete cookie now, equivalently 'Max-Age: 0'
+	// MaxAge>0 means Max-Age attribute present and given in seconds
+	MaxAge   int
+	Secure   bool
+	HttpOnly bool
+	SameSite SameSite
+	Raw      string
+	Unparsed []string // Raw text of unparsed attribute-value pairs
+}
+
+// SameSite allows a server to define a cookie attribute making it impossible for
+// the browser to send this cookie along with cross-site requests. The main
+// goal is to mitigate the risk of cross-origin information leakage, and provide
+// some protection against cross-site request forgery attacks.
+//
+// See https://tools.ietf.org/html/draft-ietf-httpbis-cookie-same-site-00 for details.
+type SameSite int
+
+const (
+	SameSiteDefaultMode SameSite = iota + 1
+	SameSiteLaxMode
+	SameSiteStrictMode
+	SameSiteNoneMode
+)
+
+// readSetCookies parses all "Set-Cookie" values from
+// the header h and returns the successfully parsed Cookies.
+func readSetCookies(h Header) []*Cookie {
+	cookieCount := len(h["Set-Cookie"])
+	if cookieCount == 0 {
+		return []*Cookie{}
+	}
+	cookies := make([]*Cookie, 0, cookieCount)
+	for _, line := range h["Set-Cookie"] {
+		parts := strings.Split(textproto.TrimString(line), ";")
+		if len(parts) == 1 && parts[0] == "" {
+			continue
+		}
+		parts[0] = textproto.TrimString(parts[0])
+		name, value, ok := strings.Cut(parts[0], "=")
+		if !ok {
+			continue
+		}
+		if !isCookieNameValid(name) {
+			continue
+		}
+		value, ok = parseCookieValue(value, true)
+		if !ok {
+			continue
+		}
+		c := &Cookie{
+			Name:  name,
+			Value: value,
+			Raw:   line,
+		}
+		for i := 1; i < len(parts); i++ {
+			parts[i] = textproto.TrimString(parts[i])
+			if len(parts[i]) == 0 {
+				continue
+			}
+
+			attr, val, _ := strings.Cut(parts[i], "=")
+			lowerAttr, isASCII := ascii.ToLower(attr)
+			if !isASCII {
+				continue
+			}
+			val, ok = parseCookieValue(val, false)
+			if !ok {
+				c.Unparsed = append(c.Unparsed, parts[i])
+				continue
+			}
+
+			switch lowerAttr {
+			case "samesite":
+				lowerVal, ascii := ascii.ToLower(val)
+				if !ascii {
+					c.SameSite = SameSiteDefaultMode
+					continue
+				}
+				switch lowerVal {
+				case "lax":
+					c.SameSite = SameSiteLaxMode
+				case "strict":
+					c.SameSite = SameSiteStrictMode
+				case "none":
+					c.SameSite = SameSiteNoneMode
+				default:
+					c.SameSite = SameSiteDefaultMode
+				}
+				continue
+			case "secure":
+				c.Secure = true
+				continue
+			case "httponly":
+				c.HttpOnly = true
+				continue
+			case "domain":
+				c.Domain = val
+				continue
+			case "max-age":
+				secs, err := strconv.Atoi(val)
+				if err != nil || secs != 0 && val[0] == '0' {
+					break
+				}
+				if secs <= 0 {
+					secs = -1
+				}
+				c.MaxAge = secs
+				continue
+			case "expires":
+				c.RawExpires = val
+				exptime, err := time.Parse(time.RFC1123, val)
+				if err != nil {
+					exptime, err = time.Parse("Mon, 02-Jan-2006 15:04:05 MST", val)
+					if err != nil {
+						c.Expires = time.Time{}
+						break
+					}
+				}
+				c.Expires = exptime.UTC()
+				continue
+			case "path":
+				c.Path = val
+				continue
+			}
+			c.Unparsed = append(c.Unparsed, parts[i])
+		}
+		cookies = append(cookies, c)
+	}
+	return cookies
+}
+
+// SetCookie adds a Set-Cookie header to the provided ResponseWriter's headers.
+// The provided cookie must have a valid Name. Invalid cookies may be
+// silently dropped.
+func SetCookie(w ResponseWriter, cookie *Cookie) {
+	if v := cookie.String(); v != "" {
+		w.Header().Add("Set-Cookie", v)
+	}
+}
+
+// String returns the serialization of the cookie for use in a Cookie
+// header (if only Name and Value are set) or a Set-Cookie response
+// header (if other fields are set).
+// If c is nil or c.Name is invalid, the empty string is returned.
+func (c *Cookie) String() string {
+	if c == nil || !isCookieNameValid(c.Name) {
+		return ""
+	}
+	// extraCookieLength derived from typical length of cookie attributes
+	// see RFC 6265 Sec 4.1.
+	const extraCookieLength = 110
+	var b strings.Builder
+	b.Grow(len(c.Name) + len(c.Value) + len(c.Domain) + len(c.Path) + extraCookieLength)
+	b.WriteString(c.Name)
+	b.WriteRune('=')
+	b.WriteString(sanitizeCookieValue(c.Value))
+
+	if len(c.Path) > 0 {
+		b.WriteString("; Path=")
+		b.WriteString(sanitizeCookiePath(c.Path))
+	}
+	if len(c.Domain) > 0 {
+		if validCookieDomain(c.Domain) {
+			// A c.Domain containing illegal characters is not
+			// sanitized but simply dropped which turns the cookie
+			// into a host-only cookie. A leading dot is okay
+			// but won't be sent.
+			d := c.Domain
+			if d[0] == '.' {
+				d = d[1:]
+			}
+			b.WriteString("; Domain=")
+			b.WriteString(d)
+		} else {
+			log.Printf("net/http: invalid Cookie.Domain %q; dropping domain attribute", c.Domain)
+		}
+	}
+	var buf [len(TimeFormat)]byte
+	if validCookieExpires(c.Expires) {
+		b.WriteString("; Expires=")
+		b.Write(c.Expires.UTC().AppendFormat(buf[:0], TimeFormat))
+	}
+	if c.MaxAge > 0 {
+		b.WriteString("; Max-Age=")
+		b.Write(strconv.AppendInt(buf[:0], int64(c.MaxAge), 10))
+	} else if c.MaxAge < 0 {
+		b.WriteString("; Max-Age=0")
+	}
+	if c.HttpOnly {
+		b.WriteString("; HttpOnly")
+	}
+	if c.Secure {
+		b.WriteString("; Secure")
+	}
+	switch c.SameSite {
+	case SameSiteDefaultMode:
+		// Skip, default mode is obtained by not emitting the attribute.
+	case SameSiteNoneMode:
+		b.WriteString("; SameSite=None")
+	case SameSiteLaxMode:
+		b.WriteString("; SameSite=Lax")
+	case SameSiteStrictMode:
+		b.WriteString("; SameSite=Strict")
+	}
+	return b.String()
+}
+
+// Valid reports whether the cookie is valid.
+func (c *Cookie) Valid() error {
+	if c == nil {
+		return errors.New("http: nil Cookie")
+	}
+	if !isCookieNameValid(c.Name) {
+		return errors.New("http: invalid Cookie.Name")
+	}
+	if !validCookieExpires(c.Expires) {
+		return errors.New("http: invalid Cookie.Expires")
+	}
+	for i := 0; i < len(c.Value); i++ {
+		if !validCookieValueByte(c.Value[i]) {
+			return fmt.Errorf("http: invalid byte %q in Cookie.Value", c.Value[i])
+		}
+	}
+	if len(c.Path) > 0 {
+		for i := 0; i < len(c.Path); i++ {
+			if !validCookiePathByte(c.Path[i]) {
+				return fmt.Errorf("http: invalid byte %q in Cookie.Path", c.Path[i])
+			}
+		}
+	}
+	if len(c.Domain) > 0 {
+		if !validCookieDomain(c.Domain) {
+			return errors.New("http: invalid Cookie.Domain")
+		}
+	}
+	return nil
+}
+
+// readCookies parses all "Cookie" values from the header h and
+// returns the successfully parsed Cookies.
+//
+// if filter isn't empty, only cookies of that name are returned
+func readCookies(h Header, filter string) []*Cookie {
+	lines := h["Cookie"]
+	if len(lines) == 0 {
+		return []*Cookie{}
+	}
+
+	cookies := make([]*Cookie, 0, len(lines)+strings.Count(lines[0], ";"))
+	for _, line := range lines {
+		line = textproto.TrimString(line)
+
+		var part string
+		for len(line) > 0 { // continue since we have rest
+			part, line, _ = strings.Cut(line, ";")
+			part = textproto.TrimString(part)
+			if part == "" {
+				continue
+			}
+			name, val, _ := strings.Cut(part, "=")
+			if !isCookieNameValid(name) {
+				continue
+			}
+			if filter != "" && filter != name {
+				continue
+			}
+			val, ok := parseCookieValue(val, true)
+			if !ok {
+				continue
+			}
+			cookies = append(cookies, &Cookie{Name: name, Value: val})
+		}
+	}
+	return cookies
+}
+
+// validCookieDomain reports whether v is a valid cookie domain-value.
+func validCookieDomain(v string) bool {
+	if isCookieDomainName(v) {
+		return true
+	}
+	if net.ParseIP(v) != nil && !strings.Contains(v, ":") {
+		return true
+	}
+	return false
+}
+
+// validCookieExpires reports whether v is a valid cookie expires-value.
+func validCookieExpires(t time.Time) bool {
+	// IETF RFC 6265 Section 5.1.1.5, the year must not be less than 1601
+	return t.Year() >= 1601
+}
+
+// isCookieDomainName reports whether s is a valid domain name or a valid
+// domain name with a leading dot '.'.  It is almost a direct copy of
+// package net's isDomainName.
+func isCookieDomainName(s string) bool {
+	if len(s) == 0 {
+		return false
+	}
+	if len(s) > 255 {
+		return false
+	}
+
+	if s[0] == '.' {
+		// A cookie a domain attribute may start with a leading dot.
+		s = s[1:]
+	}
+	last := byte('.')
+	ok := false // Ok once we've seen a letter.
+	partlen := 0
+	for i := 0; i < len(s); i++ {
+		c := s[i]
+		switch {
+		default:
+			return false
+		case 'a' <= c && c <= 'z' || 'A' <= c && c <= 'Z':
+			// No '_' allowed here (in contrast to package net).
+			ok = true
+			partlen++
+		case '0' <= c && c <= '9':
+			// fine
+			partlen++
+		case c == '-':
+			// Byte before dash cannot be dot.
+			if last == '.' {
+				return false
+			}
+			partlen++
+		case c == '.':
+			// Byte before dot cannot be dot, dash.
+			if last == '.' || last == '-' {
+				return false
+			}
+			if partlen > 63 || partlen == 0 {
+				return false
+			}
+			partlen = 0
+		}
+		last = c
+	}
+	if last == '-' || partlen > 63 {
+		return false
+	}
+
+	return ok
+}
+
+var cookieNameSanitizer = strings.NewReplacer("\n", "-", "\r", "-")
+
+func sanitizeCookieName(n string) string {
+	return cookieNameSanitizer.Replace(n)
+}
+
+// sanitizeCookieValue produces a suitable cookie-value from v.
+// https://tools.ietf.org/html/rfc6265#section-4.1.1
+//
+//	cookie-value      = *cookie-octet / ( DQUOTE *cookie-octet DQUOTE )
+//	cookie-octet      = %x21 / %x23-2B / %x2D-3A / %x3C-5B / %x5D-7E
+//	          ; US-ASCII characters excluding CTLs,
+//	          ; whitespace DQUOTE, comma, semicolon,
+//	          ; and backslash
+//
+// We loosen this as spaces and commas are common in cookie values
+// but we produce a quoted cookie-value if and only if v contains
+// commas or spaces.
+// See https://golang.org/issue/7243 for the discussion.
+func sanitizeCookieValue(v string) string {
+	v = sanitizeOrWarn("Cookie.Value", validCookieValueByte, v)
+	if len(v) == 0 {
+		return v
+	}
+	if strings.ContainsAny(v, " ,") {
+		return `"` + v + `"`
+	}
+	return v
+}
+
+func validCookieValueByte(b byte) bool {
+	return 0x20 <= b && b < 0x7f && b != '"' && b != ';' && b != '\\'
+}
+
+// path-av           = "Path=" path-value
+// path-value        = <any CHAR except CTLs or ";">
+func sanitizeCookiePath(v string) string {
+	return sanitizeOrWarn("Cookie.Path", validCookiePathByte, v)
+}
+
+func validCookiePathByte(b byte) bool {
+	return 0x20 <= b && b < 0x7f && b != ';'
+}
+
+func sanitizeOrWarn(fieldName string, valid func(byte) bool, v string) string {
+	ok := true
+	for i := 0; i < len(v); i++ {
+		if valid(v[i]) {
+			continue
+		}
+		log.Printf("net/http: invalid byte %q in %s; dropping invalid bytes", v[i], fieldName)
+		ok = false
+		break
+	}
+	if ok {
+		return v
+	}
+	buf := make([]byte, 0, len(v))
+	for i := 0; i < len(v); i++ {
+		if b := v[i]; valid(b) {
+			buf = append(buf, b)
+		}
+	}
+	return string(buf)
+}
+
+func parseCookieValue(raw string, allowDoubleQuote bool) (string, bool) {
+	// Strip the quotes, if present.
+	if allowDoubleQuote && len(raw) > 1 && raw[0] == '"' && raw[len(raw)-1] == '"' {
+		raw = raw[1 : len(raw)-1]
+	}
+	for i := 0; i < len(raw); i++ {
+		if !validCookieValueByte(raw[i]) {
+			return "", false
+		}
+	}
+	return raw, true
+}
+
+func isCookieNameValid(raw string) bool {
+	if raw == "" {
+		return false
+	}
+	return strings.IndexFunc(raw, isNotToken) < 0
+}
diff --git a/contrib/go/_std_1.19/src/net/http/doc.go b/contrib/go/_std_1.19/src/net/http/doc.go
new file mode 100644
index 0000000000..67c4246c60
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/http/doc.go
@@ -0,0 +1,106 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package http provides HTTP client and server implementations.
+
+Get, Head, Post, and PostForm make HTTP (or HTTPS) requests:
+
+	resp, err := http.Get("http://example.com/")
+	...
+	resp, err := http.Post("http://example.com/upload", "image/jpeg", &buf)
+	...
+	resp, err := http.PostForm("http://example.com/form",
+		url.Values{"key": {"Value"}, "id": {"123"}})
+
+The client must close the response body when finished with it:
+
+	resp, err := http.Get("http://example.com/")
+	if err != nil {
+		// handle error
+	}
+	defer resp.Body.Close()
+	body, err := io.ReadAll(resp.Body)
+	// ...
+
+For control over HTTP client headers, redirect policy, and other
+settings, create a Client:
+
+	client := &http.Client{
+		CheckRedirect: redirectPolicyFunc,
+	}
+
+	resp, err := client.Get("http://example.com")
+	// ...
+
+	req, err := http.NewRequest("GET", "http://example.com", nil)
+	// ...
+	req.Header.Add("If-None-Match", `W/"wyzzy"`)
+	resp, err := client.Do(req)
+	// ...
+
+For control over proxies, TLS configuration, keep-alives,
+compression, and other settings, create a Transport:
+
+	tr := &http.Transport{
+		MaxIdleConns:       10,
+		IdleConnTimeout:    30 * time.Second,
+		DisableCompression: true,
+	}
+	client := &http.Client{Transport: tr}
+	resp, err := client.Get("https://example.com")
+
+Clients and Transports are safe for concurrent use by multiple
+goroutines and for efficiency should only be created once and re-used.
+
+ListenAndServe starts an HTTP server with a given address and handler.
+The handler is usually nil, which means to use DefaultServeMux.
+Handle and HandleFunc add handlers to DefaultServeMux:
+
+	http.Handle("/foo", fooHandler)
+
+	http.HandleFunc("/bar", func(w http.ResponseWriter, r *http.Request) {
+		fmt.Fprintf(w, "Hello, %q", html.EscapeString(r.URL.Path))
+	})
+
+	log.Fatal(http.ListenAndServe(":8080", nil))
+
+More control over the server's behavior is available by creating a
+custom Server:
+
+	s := &http.Server{
+		Addr:           ":8080",
+		Handler:        myHandler,
+		ReadTimeout:    10 * time.Second,
+		WriteTimeout:   10 * time.Second,
+		MaxHeaderBytes: 1 << 20,
+	}
+	log.Fatal(s.ListenAndServe())
+
+Starting with Go 1.6, the http package has transparent support for the
+HTTP/2 protocol when using HTTPS. Programs that must disable HTTP/2
+can do so by setting Transport.TLSNextProto (for clients) or
+Server.TLSNextProto (for servers) to a non-nil, empty
+map. Alternatively, the following GODEBUG environment variables are
+currently supported:
+
+	GODEBUG=http2client=0  # disable HTTP/2 client support
+	GODEBUG=http2server=0  # disable HTTP/2 server support
+	GODEBUG=http2debug=1   # enable verbose HTTP/2 debug logs
+	GODEBUG=http2debug=2   # ... even more verbose, with frame dumps
+
+The GODEBUG variables are not covered by Go's API compatibility
+promise. Please report any issues before disabling HTTP/2
+support: https://golang.org/s/http2bug
+
+The http package's Transport and Server both automatically enable
+HTTP/2 support for simple configurations. To enable HTTP/2 for more
+complex configurations, to use lower-level HTTP/2 features, or to use
+a newer version of Go's http2 package, import "golang.org/x/net/http2"
+directly and use its ConfigureTransport and/or ConfigureServer
+functions. Manually configuring HTTP/2 via the golang.org/x/net/http2
+package takes precedence over the net/http package's built-in HTTP/2
+support.
+*/
+package http
diff --git a/contrib/go/_std_1.19/src/net/http/filetransport.go b/contrib/go/_std_1.19/src/net/http/filetransport.go
new file mode 100644
index 0000000000..94684b07a1
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/http/filetransport.go
@@ -0,0 +1,123 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package http
+
+import (
+	"fmt"
+	"io"
+)
+
+// fileTransport implements RoundTripper for the 'file' protocol.
+type fileTransport struct {
+	fh fileHandler
+}
+
+// NewFileTransport returns a new RoundTripper, serving the provided
+// FileSystem. The returned RoundTripper ignores the URL host in its
+// incoming requests, as well as most other properties of the
+// request.
+//
+// The typical use case for NewFileTransport is to register the "file"
+// protocol with a Transport, as in:
+//
+//	t := &http.Transport{}
+//	t.RegisterProtocol("file", http.NewFileTransport(http.Dir("/")))
+//	c := &http.Client{Transport: t}
+//	res, err := c.Get("file:///etc/passwd")
+//	...
+func NewFileTransport(fs FileSystem) RoundTripper {
+	return fileTransport{fileHandler{fs}}
+}
+
+func (t fileTransport) RoundTrip(req *Request) (resp *Response, err error) {
+	// We start ServeHTTP in a goroutine, which may take a long
+	// time if the file is large. The newPopulateResponseWriter
+	// call returns a channel which either ServeHTTP or finish()
+	// sends our *Response on, once the *Response itself has been
+	// populated (even if the body itself is still being
+	// written to the res.Body, a pipe)
+	rw, resc := newPopulateResponseWriter()
+	go func() {
+		t.fh.ServeHTTP(rw, req)
+		rw.finish()
+	}()
+	return <-resc, nil
+}
+
+func newPopulateResponseWriter() (*populateResponse, <-chan *Response) {
+	pr, pw := io.Pipe()
+	rw := &populateResponse{
+		ch: make(chan *Response),
+		pw: pw,
+		res: &Response{
+			Proto:      "HTTP/1.0",
+			ProtoMajor: 1,
+			Header:     make(Header),
+			Close:      true,
+			Body:       pr,
+		},
+	}
+	return rw, rw.ch
+}
+
+// populateResponse is a ResponseWriter that populates the *Response
+// in res, and writes its body to a pipe connected to the response
+// body. Once writes begin or finish() is called, the response is sent
+// on ch.
+type populateResponse struct {
+	res          *Response
+	ch           chan *Response
+	wroteHeader  bool
+	hasContent   bool
+	sentResponse bool
+	pw           *io.PipeWriter
+}
+
+func (pr *populateResponse) finish() {
+	if !pr.wroteHeader {
+		pr.WriteHeader(500)
+	}
+	if !pr.sentResponse {
+		pr.sendResponse()
+	}
+	pr.pw.Close()
+}
+
+func (pr *populateResponse) sendResponse() {
+	if pr.sentResponse {
+		return
+	}
+	pr.sentResponse = true
+
+	if pr.hasContent {
+		pr.res.ContentLength = -1
+	}
+	pr.ch <- pr.res
+}
+
+func (pr *populateResponse) Header() Header {
+	return pr.res.Header
+}
+
+func (pr *populateResponse) WriteHeader(code int) {
+	if pr.wroteHeader {
+		return
+	}
+	pr.wroteHeader = true
+
+	pr.res.StatusCode = code
+	pr.res.Status = fmt.Sprintf("%d %s", code, StatusText(code))
+}
+
+func (pr *populateResponse) Write(p []byte) (n int, err error) {
+	if !pr.wroteHeader {
+		pr.WriteHeader(StatusOK)
+	}
+	pr.hasContent = true
+	if !pr.sentResponse {
+		pr.sendResponse()
+	}
+	return pr.pw.Write(p)
+}
diff --git a/contrib/go/_std_1.19/src/net/http/fs.go b/contrib/go/_std_1.19/src/net/http/fs.go
new file mode 100644
index 0000000000..4f144ebad2
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/http/fs.go
@@ -0,0 +1,972 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// HTTP file system request handler
+
+package http
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"io/fs"
+	"mime"
+	"mime/multipart"
+	"net/textproto"
+	"net/url"
+	"os"
+	"path"
+	"path/filepath"
+	"sort"
+	"strconv"
+	"strings"
+	"time"
+)
+
+// A Dir implements FileSystem using the native file system restricted to a
+// specific directory tree.
+//
+// While the FileSystem.Open method takes '/'-separated paths, a Dir's string
+// value is a filename on the native file system, not a URL, so it is separated
+// by filepath.Separator, which isn't necessarily '/'.
+//
+// Note that Dir could expose sensitive files and directories. Dir will follow
+// symlinks pointing out of the directory tree, which can be especially dangerous
+// if serving from a directory in which users are able to create arbitrary symlinks.
+// Dir will also allow access to files and directories starting with a period,
+// which could expose sensitive directories like .git or sensitive files like
+// .htpasswd. To exclude files with a leading period, remove the files/directories
+// from the server or create a custom FileSystem implementation.
+//
+// An empty Dir is treated as ".".
+type Dir string
+
+// mapOpenError maps the provided non-nil error from opening name
+// to a possibly better non-nil error. In particular, it turns OS-specific errors
+// about opening files in non-directories into fs.ErrNotExist. See Issues 18984 and 49552.
+func mapOpenError(originalErr error, name string, sep rune, stat func(string) (fs.FileInfo, error)) error {
+	if errors.Is(originalErr, fs.ErrNotExist) || errors.Is(originalErr, fs.ErrPermission) {
+		return originalErr
+	}
+
+	parts := strings.Split(name, string(sep))
+	for i := range parts {
+		if parts[i] == "" {
+			continue
+		}
+		fi, err := stat(strings.Join(parts[:i+1], string(sep)))
+		if err != nil {
+			return originalErr
+		}
+		if !fi.IsDir() {
+			return fs.ErrNotExist
+		}
+	}
+	return originalErr
+}
+
+// Open implements FileSystem using os.Open, opening files for reading rooted
+// and relative to the directory d.
+func (d Dir) Open(name string) (File, error) {
+	if filepath.Separator != '/' && strings.ContainsRune(name, filepath.Separator) {
+		return nil, errors.New("http: invalid character in file path")
+	}
+	dir := string(d)
+	if dir == "" {
+		dir = "."
+	}
+	fullName := filepath.Join(dir, filepath.FromSlash(path.Clean("/"+name)))
+	f, err := os.Open(fullName)
+	if err != nil {
+		return nil, mapOpenError(err, fullName, filepath.Separator, os.Stat)
+	}
+	return f, nil
+}
+
+// A FileSystem implements access to a collection of named files.
+// The elements in a file path are separated by slash ('/', U+002F)
+// characters, regardless of host operating system convention.
+// See the FileServer function to convert a FileSystem to a Handler.
+//
+// This interface predates the fs.FS interface, which can be used instead:
+// the FS adapter function converts an fs.FS to a FileSystem.
+type FileSystem interface {
+	Open(name string) (File, error)
+}
+
+// A File is returned by a FileSystem's Open method and can be
+// served by the FileServer implementation.
+//
+// The methods should behave the same as those on an *os.File.
+type File interface {
+	io.Closer
+	io.Reader
+	io.Seeker
+	Readdir(count int) ([]fs.FileInfo, error)
+	Stat() (fs.FileInfo, error)
+}
+
+type anyDirs interface {
+	len() int
+	name(i int) string
+	isDir(i int) bool
+}
+
+type fileInfoDirs []fs.FileInfo
+
+func (d fileInfoDirs) len() int          { return len(d) }
+func (d fileInfoDirs) isDir(i int) bool  { return d[i].IsDir() }
+func (d fileInfoDirs) name(i int) string { return d[i].Name() }
+
+type dirEntryDirs []fs.DirEntry
+
+func (d dirEntryDirs) len() int          { return len(d) }
+func (d dirEntryDirs) isDir(i int) bool  { return d[i].IsDir() }
+func (d dirEntryDirs) name(i int) string { return d[i].Name() }
+
+func dirList(w ResponseWriter, r *Request, f File) {
+	// Prefer to use ReadDir instead of Readdir,
+	// because the former doesn't require calling
+	// Stat on every entry of a directory on Unix.
+	var dirs anyDirs
+	var err error
+	if d, ok := f.(fs.ReadDirFile); ok {
+		var list dirEntryDirs
+		list, err = d.ReadDir(-1)
+		dirs = list
+	} else {
+		var list fileInfoDirs
+		list, err = f.Readdir(-1)
+		dirs = list
+	}
+
+	if err != nil {
+		logf(r, "http: error reading directory: %v", err)
+		Error(w, "Error reading directory", StatusInternalServerError)
+		return
+	}
+	sort.Slice(dirs, func(i, j int) bool { return dirs.name(i) < dirs.name(j) })
+
+	w.Header().Set("Content-Type", "text/html; charset=utf-8")
+	fmt.Fprintf(w, "<pre>\n")
+	for i, n := 0, dirs.len(); i < n; i++ {
+		name := dirs.name(i)
+		if dirs.isDir(i) {
+			name += "/"
+		}
+		// name may contain '?' or '#', which must be escaped to remain
+		// part of the URL path, and not indicate the start of a query
+		// string or fragment.
+		url := url.URL{Path: name}
+		fmt.Fprintf(w, "<a href=\"%s\">%s</a>\n", url.String(), htmlReplacer.Replace(name))
+	}
+	fmt.Fprintf(w, "</pre>\n")
+}
+
+// ServeContent replies to the request using the content in the
+// provided ReadSeeker. The main benefit of ServeContent over io.Copy
+// is that it handles Range requests properly, sets the MIME type, and
+// handles If-Match, If-Unmodified-Since, If-None-Match, If-Modified-Since,
+// and If-Range requests.
+//
+// If the response's Content-Type header is not set, ServeContent
+// first tries to deduce the type from name's file extension and,
+// if that fails, falls back to reading the first block of the content
+// and passing it to DetectContentType.
+// The name is otherwise unused; in particular it can be empty and is
+// never sent in the response.
+//
+// If modtime is not the zero time or Unix epoch, ServeContent
+// includes it in a Last-Modified header in the response. If the
+// request includes an If-Modified-Since header, ServeContent uses
+// modtime to decide whether the content needs to be sent at all.
+//
+// The content's Seek method must work: ServeContent uses
+// a seek to the end of the content to determine its size.
+//
+// If the caller has set w's ETag header formatted per RFC 7232, section 2.3,
+// ServeContent uses it to handle requests using If-Match, If-None-Match, or If-Range.
+//
+// Note that *os.File implements the io.ReadSeeker interface.
+func ServeContent(w ResponseWriter, req *Request, name string, modtime time.Time, content io.ReadSeeker) {
+	sizeFunc := func() (int64, error) {
+		size, err := content.Seek(0, io.SeekEnd)
+		if err != nil {
+			return 0, errSeeker
+		}
+		_, err = content.Seek(0, io.SeekStart)
+		if err != nil {
+			return 0, errSeeker
+		}
+		return size, nil
+	}
+	serveContent(w, req, name, modtime, sizeFunc, content)
+}
+
+// errSeeker is returned by ServeContent's sizeFunc when the content
+// doesn't seek properly. The underlying Seeker's error text isn't
+// included in the sizeFunc reply so it's not sent over HTTP to end
+// users.
+var errSeeker = errors.New("seeker can't seek")
+
+// errNoOverlap is returned by serveContent's parseRange if first-byte-pos of
+// all of the byte-range-spec values is greater than the content size.
+var errNoOverlap = errors.New("invalid range: failed to overlap")
+
+// if name is empty, filename is unknown. (used for mime type, before sniffing)
+// if modtime.IsZero(), modtime is unknown.
+// content must be seeked to the beginning of the file.
+// The sizeFunc is called at most once. Its error, if any, is sent in the HTTP response.
+func serveContent(w ResponseWriter, r *Request, name string, modtime time.Time, sizeFunc func() (int64, error), content io.ReadSeeker) {
+	setLastModified(w, modtime)
+	done, rangeReq := checkPreconditions(w, r, modtime)
+	if done {
+		return
+	}
+
+	code := StatusOK
+
+	// If Content-Type isn't set, use the file's extension to find it, but
+	// if the Content-Type is unset explicitly, do not sniff the type.
+	ctypes, haveType := w.Header()["Content-Type"]
+	var ctype string
+	if !haveType {
+		ctype = mime.TypeByExtension(filepath.Ext(name))
+		if ctype == "" {
+			// read a chunk to decide between utf-8 text and binary
+			var buf [sniffLen]byte
+			n, _ := io.ReadFull(content, buf[:])
+			ctype = DetectContentType(buf[:n])
+			_, err := content.Seek(0, io.SeekStart) // rewind to output whole file
+			if err != nil {
+				Error(w, "seeker can't seek", StatusInternalServerError)
+				return
+			}
+		}
+		w.Header().Set("Content-Type", ctype)
+	} else if len(ctypes) > 0 {
+		ctype = ctypes[0]
+	}
+
+	size, err := sizeFunc()
+	if err != nil {
+		Error(w, err.Error(), StatusInternalServerError)
+		return
+	}
+
+	// handle Content-Range header.
+	sendSize := size
+	var sendContent io.Reader = content
+	if size >= 0 {
+		ranges, err := parseRange(rangeReq, size)
+		if err != nil {
+			if err == errNoOverlap {
+				w.Header().Set("Content-Range", fmt.Sprintf("bytes */%d", size))
+			}
+			Error(w, err.Error(), StatusRequestedRangeNotSatisfiable)
+			return
+		}
+		if sumRangesSize(ranges) > size {
+			// The total number of bytes in all the ranges
+			// is larger than the size of the file by
+			// itself, so this is probably an attack, or a
+			// dumb client. Ignore the range request.
+			ranges = nil
+		}
+		switch {
+		case len(ranges) == 1:
+			// RFC 7233, Section 4.1:
+			// "If a single part is being transferred, the server
+			// generating the 206 response MUST generate a
+			// Content-Range header field, describing what range
+			// of the selected representation is enclosed, and a
+			// payload consisting of the range.
+			// ...
+			// A server MUST NOT generate a multipart response to
+			// a request for a single range, since a client that
+			// does not request multiple parts might not support
+			// multipart responses."
+			ra := ranges[0]
+			if _, err := content.Seek(ra.start, io.SeekStart); err != nil {
+				Error(w, err.Error(), StatusRequestedRangeNotSatisfiable)
+				return
+			}
+			sendSize = ra.length
+			code = StatusPartialContent
+			w.Header().Set("Content-Range", ra.contentRange(size))
+		case len(ranges) > 1:
+			sendSize = rangesMIMESize(ranges, ctype, size)
+			code = StatusPartialContent
+
+			pr, pw := io.Pipe()
+			mw := multipart.NewWriter(pw)
+			w.Header().Set("Content-Type", "multipart/byteranges; boundary="+mw.Boundary())
+			sendContent = pr
+			defer pr.Close() // cause writing goroutine to fail and exit if CopyN doesn't finish.
+			go func() {
+				for _, ra := range ranges {
+					part, err := mw.CreatePart(ra.mimeHeader(ctype, size))
+					if err != nil {
+						pw.CloseWithError(err)
+						return
+					}
+					if _, err := content.Seek(ra.start, io.SeekStart); err != nil {
+						pw.CloseWithError(err)
+						return
+					}
+					if _, err := io.CopyN(part, content, ra.length); err != nil {
+						pw.CloseWithError(err)
+						return
+					}
+				}
+				mw.Close()
+				pw.Close()
+			}()
+		}
+
+		w.Header().Set("Accept-Ranges", "bytes")
+		if w.Header().Get("Content-Encoding") == "" {
+			w.Header().Set("Content-Length", strconv.FormatInt(sendSize, 10))
+		}
+	}
+
+	w.WriteHeader(code)
+
+	if r.Method != "HEAD" {
+		io.CopyN(w, sendContent, sendSize)
+	}
+}
+
+// scanETag determines if a syntactically valid ETag is present at s. If so,
+// the ETag and remaining text after consuming ETag is returned. Otherwise,
+// it returns "", "".
+func scanETag(s string) (etag string, remain string) {
+	s = textproto.TrimString(s)
+	start := 0
+	if strings.HasPrefix(s, "W/") {
+		start = 2
+	}
+	if len(s[start:]) < 2 || s[start] != '"' {
+		return "", ""
+	}
+	// ETag is either W/"text" or "text".
+	// See RFC 7232 2.3.
+	for i := start + 1; i < len(s); i++ {
+		c := s[i]
+		switch {
+		// Character values allowed in ETags.
+		case c == 0x21 || c >= 0x23 && c <= 0x7E || c >= 0x80:
+		case c == '"':
+			return s[:i+1], s[i+1:]
+		default:
+			return "", ""
+		}
+	}
+	return "", ""
+}
+
+// etagStrongMatch reports whether a and b match using strong ETag comparison.
+// Assumes a and b are valid ETags.
+func etagStrongMatch(a, b string) bool {
+	return a == b && a != "" && a[0] == '"'
+}
+
+// etagWeakMatch reports whether a and b match using weak ETag comparison.
+// Assumes a and b are valid ETags.
+func etagWeakMatch(a, b string) bool {
+	return strings.TrimPrefix(a, "W/") == strings.TrimPrefix(b, "W/")
+}
+
+// condResult is the result of an HTTP request precondition check.
+// See https://tools.ietf.org/html/rfc7232 section 3.
+type condResult int
+
+const (
+	condNone condResult = iota
+	condTrue
+	condFalse
+)
+
+func checkIfMatch(w ResponseWriter, r *Request) condResult {
+	im := r.Header.Get("If-Match")
+	if im == "" {
+		return condNone
+	}
+	for {
+		im = textproto.TrimString(im)
+		if len(im) == 0 {
+			break
+		}
+		if im[0] == ',' {
+			im = im[1:]
+			continue
+		}
+		if im[0] == '*' {
+			return condTrue
+		}
+		etag, remain := scanETag(im)
+		if etag == "" {
+			break
+		}
+		if etagStrongMatch(etag, w.Header().get("Etag")) {
+			return condTrue
+		}
+		im = remain
+	}
+
+	return condFalse
+}
+
+func checkIfUnmodifiedSince(r *Request, modtime time.Time) condResult {
+	ius := r.Header.Get("If-Unmodified-Since")
+	if ius == "" || isZeroTime(modtime) {
+		return condNone
+	}
+	t, err := ParseTime(ius)
+	if err != nil {
+		return condNone
+	}
+
+	// The Last-Modified header truncates sub-second precision so
+	// the modtime needs to be truncated too.
+	modtime = modtime.Truncate(time.Second)
+	if modtime.Before(t) || modtime.Equal(t) {
+		return condTrue
+	}
+	return condFalse
+}
+
+func checkIfNoneMatch(w ResponseWriter, r *Request) condResult {
+	inm := r.Header.get("If-None-Match")
+	if inm == "" {
+		return condNone
+	}
+	buf := inm
+	for {
+		buf = textproto.TrimString(buf)
+		if len(buf) == 0 {
+			break
+		}
+		if buf[0] == ',' {
+			buf = buf[1:]
+			continue
+		}
+		if buf[0] == '*' {
+			return condFalse
+		}
+		etag, remain := scanETag(buf)
+		if etag == "" {
+			break
+		}
+		if etagWeakMatch(etag, w.Header().get("Etag")) {
+			return condFalse
+		}
+		buf = remain
+	}
+	return condTrue
+}
+
+func checkIfModifiedSince(r *Request, modtime time.Time) condResult {
+	if r.Method != "GET" && r.Method != "HEAD" {
+		return condNone
+	}
+	ims := r.Header.Get("If-Modified-Since")
+	if ims == "" || isZeroTime(modtime) {
+		return condNone
+	}
+	t, err := ParseTime(ims)
+	if err != nil {
+		return condNone
+	}
+	// The Last-Modified header truncates sub-second precision so
+	// the modtime needs to be truncated too.
+	modtime = modtime.Truncate(time.Second)
+	if modtime.Before(t) || modtime.Equal(t) {
+		return condFalse
+	}
+	return condTrue
+}
+
+func checkIfRange(w ResponseWriter, r *Request, modtime time.Time) condResult {
+	if r.Method != "GET" && r.Method != "HEAD" {
+		return condNone
+	}
+	ir := r.Header.get("If-Range")
+	if ir == "" {
+		return condNone
+	}
+	etag, _ := scanETag(ir)
+	if etag != "" {
+		if etagStrongMatch(etag, w.Header().Get("Etag")) {
+			return condTrue
+		} else {
+			return condFalse
+		}
+	}
+	// The If-Range value is typically the ETag value, but it may also be
+	// the modtime date. See golang.org/issue/8367.
+	if modtime.IsZero() {
+		return condFalse
+	}
+	t, err := ParseTime(ir)
+	if err != nil {
+		return condFalse
+	}
+	if t.Unix() == modtime.Unix() {
+		return condTrue
+	}
+	return condFalse
+}
+
+var unixEpochTime = time.Unix(0, 0)
+
+// isZeroTime reports whether t is obviously unspecified (either zero or Unix()=0).
+func isZeroTime(t time.Time) bool {
+	return t.IsZero() || t.Equal(unixEpochTime)
+}
+
+func setLastModified(w ResponseWriter, modtime time.Time) {
+	if !isZeroTime(modtime) {
+		w.Header().Set("Last-Modified", modtime.UTC().Format(TimeFormat))
+	}
+}
+
+func writeNotModified(w ResponseWriter) {
+	// RFC 7232 section 4.1:
+	// a sender SHOULD NOT generate representation metadata other than the
+	// above listed fields unless said metadata exists for the purpose of
+	// guiding cache updates (e.g., Last-Modified might be useful if the
+	// response does not have an ETag field).
+	h := w.Header()
+	delete(h, "Content-Type")
+	delete(h, "Content-Length")
+	delete(h, "Content-Encoding")
+	if h.Get("Etag") != "" {
+		delete(h, "Last-Modified")
+	}
+	w.WriteHeader(StatusNotModified)
+}
+
+// checkPreconditions evaluates request preconditions and reports whether a precondition
+// resulted in sending StatusNotModified or StatusPreconditionFailed.
+func checkPreconditions(w ResponseWriter, r *Request, modtime time.Time) (done bool, rangeHeader string) {
+	// This function carefully follows RFC 7232 section 6.
+	ch := checkIfMatch(w, r)
+	if ch == condNone {
+		ch = checkIfUnmodifiedSince(r, modtime)
+	}
+	if ch == condFalse {
+		w.WriteHeader(StatusPreconditionFailed)
+		return true, ""
+	}
+	switch checkIfNoneMatch(w, r) {
+	case condFalse:
+		if r.Method == "GET" || r.Method == "HEAD" {
+			writeNotModified(w)
+			return true, ""
+		} else {
+			w.WriteHeader(StatusPreconditionFailed)
+			return true, ""
+		}
+	case condNone:
+		if checkIfModifiedSince(r, modtime) == condFalse {
+			writeNotModified(w)
+			return true, ""
+		}
+	}
+
+	rangeHeader = r.Header.get("Range")
+	if rangeHeader != "" && checkIfRange(w, r, modtime) == condFalse {
+		rangeHeader = ""
+	}
+	return false, rangeHeader
+}
+
+// name is '/'-separated, not filepath.Separator.
+func serveFile(w ResponseWriter, r *Request, fs FileSystem, name string, redirect bool) {
+	const indexPage = "/index.html"
+
+	// redirect .../index.html to .../
+	// can't use Redirect() because that would make the path absolute,
+	// which would be a problem running under StripPrefix
+	if strings.HasSuffix(r.URL.Path, indexPage) {
+		localRedirect(w, r, "./")
+		return
+	}
+
+	f, err := fs.Open(name)
+	if err != nil {
+		msg, code := toHTTPError(err)
+		Error(w, msg, code)
+		return
+	}
+	defer f.Close()
+
+	d, err := f.Stat()
+	if err != nil {
+		msg, code := toHTTPError(err)
+		Error(w, msg, code)
+		return
+	}
+
+	if redirect {
+		// redirect to canonical path: / at end of directory url
+		// r.URL.Path always begins with /
+		url := r.URL.Path
+		if d.IsDir() {
+			if url[len(url)-1] != '/' {
+				localRedirect(w, r, path.Base(url)+"/")
+				return
+			}
+		} else {
+			if url[len(url)-1] == '/' {
+				localRedirect(w, r, "../"+path.Base(url))
+				return
+			}
+		}
+	}
+
+	if d.IsDir() {
+		url := r.URL.Path
+		// redirect if the directory name doesn't end in a slash
+		if url == "" || url[len(url)-1] != '/' {
+			localRedirect(w, r, path.Base(url)+"/")
+			return
+		}
+
+		// use contents of index.html for directory, if present
+		index := strings.TrimSuffix(name, "/") + indexPage
+		ff, err := fs.Open(index)
+		if err == nil {
+			defer ff.Close()
+			dd, err := ff.Stat()
+			if err == nil {
+				name = index
+				d = dd
+				f = ff
+			}
+		}
+	}
+
+	// Still a directory? (we didn't find an index.html file)
+	if d.IsDir() {
+		if checkIfModifiedSince(r, d.ModTime()) == condFalse {
+			writeNotModified(w)
+			return
+		}
+		setLastModified(w, d.ModTime())
+		dirList(w, r, f)
+		return
+	}
+
+	// serveContent will check modification time
+	sizeFunc := func() (int64, error) { return d.Size(), nil }
+	serveContent(w, r, d.Name(), d.ModTime(), sizeFunc, f)
+}
+
+// toHTTPError returns a non-specific HTTP error message and status code
+// for a given non-nil error value. It's important that toHTTPError does not
+// actually return err.Error(), since msg and httpStatus are returned to users,
+// and historically Go's ServeContent always returned just "404 Not Found" for
+// all errors. We don't want to start leaking information in error messages.
+func toHTTPError(err error) (msg string, httpStatus int) {
+	if errors.Is(err, fs.ErrNotExist) {
+		return "404 page not found", StatusNotFound
+	}
+	if errors.Is(err, fs.ErrPermission) {
+		return "403 Forbidden", StatusForbidden
+	}
+	// Default:
+	return "500 Internal Server Error", StatusInternalServerError
+}
+
+// localRedirect gives a Moved Permanently response.
+// It does not convert relative paths to absolute paths like Redirect does.
+func localRedirect(w ResponseWriter, r *Request, newPath string) {
+	if q := r.URL.RawQuery; q != "" {
+		newPath += "?" + q
+	}
+	w.Header().Set("Location", newPath)
+	w.WriteHeader(StatusMovedPermanently)
+}
+
+// ServeFile replies to the request with the contents of the named
+// file or directory.
+//
+// If the provided file or directory name is a relative path, it is
+// interpreted relative to the current directory and may ascend to
+// parent directories. If the provided name is constructed from user
+// input, it should be sanitized before calling ServeFile.
+//
+// As a precaution, ServeFile will reject requests where r.URL.Path
+// contains a ".." path element; this protects against callers who
+// might unsafely use filepath.Join on r.URL.Path without sanitizing
+// it and then use that filepath.Join result as the name argument.
+//
+// As another special case, ServeFile redirects any request where r.URL.Path
+// ends in "/index.html" to the same path, without the final
+// "index.html". To avoid such redirects either modify the path or
+// use ServeContent.
+//
+// Outside of those two special cases, ServeFile does not use
+// r.URL.Path for selecting the file or directory to serve; only the
+// file or directory provided in the name argument is used.
+func ServeFile(w ResponseWriter, r *Request, name string) {
+	if containsDotDot(r.URL.Path) {
+		// Too many programs use r.URL.Path to construct the argument to
+		// serveFile. Reject the request under the assumption that happened
+		// here and ".." may not be wanted.
+		// Note that name might not contain "..", for example if code (still
+		// incorrectly) used filepath.Join(myDir, r.URL.Path).
+		Error(w, "invalid URL path", StatusBadRequest)
+		return
+	}
+	dir, file := filepath.Split(name)
+	serveFile(w, r, Dir(dir), file, false)
+}
+
+func containsDotDot(v string) bool {
+	if !strings.Contains(v, "..") {
+		return false
+	}
+	for _, ent := range strings.FieldsFunc(v, isSlashRune) {
+		if ent == ".." {
+			return true
+		}
+	}
+	return false
+}
+
+func isSlashRune(r rune) bool { return r == '/' || r == '\\' }
+
+type fileHandler struct {
+	root FileSystem
+}
+
+type ioFS struct {
+	fsys fs.FS
+}
+
+type ioFile struct {
+	file fs.File
+}
+
+func (f ioFS) Open(name string) (File, error) {
+	if name == "/" {
+		name = "."
+	} else {
+		name = strings.TrimPrefix(name, "/")
+	}
+	file, err := f.fsys.Open(name)
+	if err != nil {
+		return nil, mapOpenError(err, name, '/', func(path string) (fs.FileInfo, error) {
+			return fs.Stat(f.fsys, path)
+		})
+	}
+	return ioFile{file}, nil
+}
+
+func (f ioFile) Close() error               { return f.file.Close() }
+func (f ioFile) Read(b []byte) (int, error) { return f.file.Read(b) }
+func (f ioFile) Stat() (fs.FileInfo, error) { return f.file.Stat() }
+
+var errMissingSeek = errors.New("io.File missing Seek method")
+var errMissingReadDir = errors.New("io.File directory missing ReadDir method")
+
+func (f ioFile) Seek(offset int64, whence int) (int64, error) {
+	s, ok := f.file.(io.Seeker)
+	if !ok {
+		return 0, errMissingSeek
+	}
+	return s.Seek(offset, whence)
+}
+
+func (f ioFile) ReadDir(count int) ([]fs.DirEntry, error) {
+	d, ok := f.file.(fs.ReadDirFile)
+	if !ok {
+		return nil, errMissingReadDir
+	}
+	return d.ReadDir(count)
+}
+
+func (f ioFile) Readdir(count int) ([]fs.FileInfo, error) {
+	d, ok := f.file.(fs.ReadDirFile)
+	if !ok {
+		return nil, errMissingReadDir
+	}
+	var list []fs.FileInfo
+	for {
+		dirs, err := d.ReadDir(count - len(list))
+		for _, dir := range dirs {
+			info, err := dir.Info()
+			if err != nil {
+				// Pretend it doesn't exist, like (*os.File).Readdir does.
+				continue
+			}
+			list = append(list, info)
+		}
+		if err != nil {
+			return list, err
+		}
+		if count < 0 || len(list) >= count {
+			break
+		}
+	}
+	return list, nil
+}
+
+// FS converts fsys to a FileSystem implementation,
+// for use with FileServer and NewFileTransport.
+func FS(fsys fs.FS) FileSystem {
+	return ioFS{fsys}
+}
+
+// FileServer returns a handler that serves HTTP requests
+// with the contents of the file system rooted at root.
+//
+// As a special case, the returned file server redirects any request
+// ending in "/index.html" to the same path, without the final
+// "index.html".
+//
+// To use the operating system's file system implementation,
+// use http.Dir:
+//
+//	http.Handle("/", http.FileServer(http.Dir("/tmp")))
+//
+// To use an fs.FS implementation, use http.FS to convert it:
+//
+//	http.Handle("/", http.FileServer(http.FS(fsys)))
+func FileServer(root FileSystem) Handler {
+	return &fileHandler{root}
+}
+
+func (f *fileHandler) ServeHTTP(w ResponseWriter, r *Request) {
+	upath := r.URL.Path
+	if !strings.HasPrefix(upath, "/") {
+		upath = "/" + upath
+		r.URL.Path = upath
+	}
+	serveFile(w, r, f.root, path.Clean(upath), true)
+}
+
+// httpRange specifies the byte range to be sent to the client.
+type httpRange struct {
+	start, length int64
+}
+
+func (r httpRange) contentRange(size int64) string {
+	return fmt.Sprintf("bytes %d-%d/%d", r.start, r.start+r.length-1, size)
+}
+
+func (r httpRange) mimeHeader(contentType string, size int64) textproto.MIMEHeader {
+	return textproto.MIMEHeader{
+		"Content-Range": {r.contentRange(size)},
+		"Content-Type":  {contentType},
+	}
+}
+
+// parseRange parses a Range header string as per RFC 7233.
+// errNoOverlap is returned if none of the ranges overlap.
+func parseRange(s string, size int64) ([]httpRange, error) {
+	if s == "" {
+		return nil, nil // header not present
+	}
+	const b = "bytes="
+	if !strings.HasPrefix(s, b) {
+		return nil, errors.New("invalid range")
+	}
+	var ranges []httpRange
+	noOverlap := false
+	for _, ra := range strings.Split(s[len(b):], ",") {
+		ra = textproto.TrimString(ra)
+		if ra == "" {
+			continue
+		}
+		start, end, ok := strings.Cut(ra, "-")
+		if !ok {
+			return nil, errors.New("invalid range")
+		}
+		start, end = textproto.TrimString(start), textproto.TrimString(end)
+		var r httpRange
+		if start == "" {
+			// If no start is specified, end specifies the
+			// range start relative to the end of the file,
+			// and we are dealing with <suffix-length>
+			// which has to be a non-negative integer as per
+			// RFC 7233 Section 2.1 "Byte-Ranges".
+			if end == "" || end[0] == '-' {
+				return nil, errors.New("invalid range")
+			}
+			i, err := strconv.ParseInt(end, 10, 64)
+			if i < 0 || err != nil {
+				return nil, errors.New("invalid range")
+			}
+			if i > size {
+				i = size
+			}
+			r.start = size - i
+			r.length = size - r.start
+		} else {
+			i, err := strconv.ParseInt(start, 10, 64)
+			if err != nil || i < 0 {
+				return nil, errors.New("invalid range")
+			}
+			if i >= size {
+				// If the range begins after the size of the content,
+				// then it does not overlap.
+				noOverlap = true
+				continue
+			}
+			r.start = i
+			if end == "" {
+				// If no end is specified, range extends to end of the file.
+				r.length = size - r.start
+			} else {
+				i, err := strconv.ParseInt(end, 10, 64)
+				if err != nil || r.start > i {
+					return nil, errors.New("invalid range")
+				}
+				if i >= size {
+					i = size - 1
+				}
+				r.length = i - r.start + 1
+			}
+		}
+		ranges = append(ranges, r)
+	}
+	if noOverlap && len(ranges) == 0 {
+		// The specified ranges did not overlap with the content.
+		return nil, errNoOverlap
+	}
+	return ranges, nil
+}
+
+// countingWriter counts how many bytes have been written to it.
+type countingWriter int64
+
+func (w *countingWriter) Write(p []byte) (n int, err error) {
+	*w += countingWriter(len(p))
+	return len(p), nil
+}
+
+// rangesMIMESize returns the number of bytes it takes to encode the
+// provided ranges as a multipart response.
+func rangesMIMESize(ranges []httpRange, contentType string, contentSize int64) (encSize int64) {
+	var w countingWriter
+	mw := multipart.NewWriter(&w)
+	for _, ra := range ranges {
+		mw.CreatePart(ra.mimeHeader(contentType, contentSize))
+		encSize += ra.length
+	}
+	mw.Close()
+	encSize += int64(w)
+	return
+}
+
+func sumRangesSize(ranges []httpRange) (size int64) {
+	for _, ra := range ranges {
+		size += ra.length
+	}
+	return
+}
diff --git a/contrib/go/_std_1.19/src/net/http/h2_bundle.go b/contrib/go/_std_1.19/src/net/http/h2_bundle.go
new file mode 100644
index 0000000000..0e5fa6712e
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/http/h2_bundle.go
@@ -0,0 +1,10924 @@
+//go:build !nethttpomithttp2
+// +build !nethttpomithttp2
+
+// Code generated by golang.org/x/tools/cmd/bundle. DO NOT EDIT.
+//   $ bundle -o=h2_bundle.go -prefix=http2 -tags=!nethttpomithttp2 golang.org/x/net/http2
+
+// Package http2 implements the HTTP/2 protocol.
+//
+// This package is low-level and intended to be used directly by very
+// few people. Most users will use it indirectly through the automatic
+// use by the net/http package (from Go 1.6 and later).
+// For use in earlier Go versions see ConfigureServer. (Transport support
+// requires Go 1.6 or later)
+//
+// See https://http2.github.io/ for more information on HTTP/2.
+//
+// See https://http2.golang.org/ for a test server running this code.
+//
+
+package http
+
+import (
+	"bufio"
+	"bytes"
+	"compress/gzip"
+	"context"
+	"crypto/rand"
+	"crypto/tls"
+	"encoding/binary"
+	"errors"
+	"fmt"
+	"io"
+	"log"
+	"math"
+	mathrand "math/rand"
+	"net"
+	"net/http/httptrace"
+	"net/textproto"
+	"net/url"
+	"os"
+	"reflect"
+	"runtime"
+	"sort"
+	"strconv"
+	"strings"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"golang.org/x/net/http/httpguts"
+	"golang.org/x/net/http2/hpack"
+	"golang.org/x/net/idna"
+)
+
+// The HTTP protocols are defined in terms of ASCII, not Unicode. This file
+// contains helper functions which may use Unicode-aware functions which would
+// otherwise be unsafe and could introduce vulnerabilities if used improperly.
+
+// asciiEqualFold is strings.EqualFold, ASCII only. It reports whether s and t
+// are equal, ASCII-case-insensitively.
+func http2asciiEqualFold(s, t string) bool {
+	if len(s) != len(t) {
+		return false
+	}
+	for i := 0; i < len(s); i++ {
+		if http2lower(s[i]) != http2lower(t[i]) {
+			return false
+		}
+	}
+	return true
+}
+
+// lower returns the ASCII lowercase version of b.
+func http2lower(b byte) byte {
+	if 'A' <= b && b <= 'Z' {
+		return b + ('a' - 'A')
+	}
+	return b
+}
+
+// isASCIIPrint returns whether s is ASCII and printable according to
+// https://tools.ietf.org/html/rfc20#section-4.2.
+func http2isASCIIPrint(s string) bool {
+	for i := 0; i < len(s); i++ {
+		if s[i] < ' ' || s[i] > '~' {
+			return false
+		}
+	}
+	return true
+}
+
+// asciiToLower returns the lowercase version of s if s is ASCII and printable,
+// and whether or not it was.
+func http2asciiToLower(s string) (lower string, ok bool) {
+	if !http2isASCIIPrint(s) {
+		return "", false
+	}
+	return strings.ToLower(s), true
+}
+
+// A list of the possible cipher suite ids. Taken from
+// https://www.iana.org/assignments/tls-parameters/tls-parameters.txt
+
+const (
+	http2cipher_TLS_NULL_WITH_NULL_NULL               uint16 = 0x0000
+	http2cipher_TLS_RSA_WITH_NULL_MD5                 uint16 = 0x0001
+	http2cipher_TLS_RSA_WITH_NULL_SHA                 uint16 = 0x0002
+	http2cipher_TLS_RSA_EXPORT_WITH_RC4_40_MD5        uint16 = 0x0003
+	http2cipher_TLS_RSA_WITH_RC4_128_MD5              uint16 = 0x0004
+	http2cipher_TLS_RSA_WITH_RC4_128_SHA              uint16 = 0x0005
+	http2cipher_TLS_RSA_EXPORT_WITH_RC2_CBC_40_MD5    uint16 = 0x0006
+	http2cipher_TLS_RSA_WITH_IDEA_CBC_SHA             uint16 = 0x0007
+	http2cipher_TLS_RSA_EXPORT_WITH_DES40_CBC_SHA     uint16 = 0x0008
+	http2cipher_TLS_RSA_WITH_DES_CBC_SHA              uint16 = 0x0009
+	http2cipher_TLS_RSA_WITH_3DES_EDE_CBC_SHA         uint16 = 0x000A
+	http2cipher_TLS_DH_DSS_EXPORT_WITH_DES40_CBC_SHA  uint16 = 0x000B
+	http2cipher_TLS_DH_DSS_WITH_DES_CBC_SHA           uint16 = 0x000C
+	http2cipher_TLS_DH_DSS_WITH_3DES_EDE_CBC_SHA      uint16 = 0x000D
+	http2cipher_TLS_DH_RSA_EXPORT_WITH_DES40_CBC_SHA  uint16 = 0x000E
+	http2cipher_TLS_DH_RSA_WITH_DES_CBC_SHA           uint16 = 0x000F
+	http2cipher_TLS_DH_RSA_WITH_3DES_EDE_CBC_SHA      uint16 = 0x0010
+	http2cipher_TLS_DHE_DSS_EXPORT_WITH_DES40_CBC_SHA uint16 = 0x0011
+	http2cipher_TLS_DHE_DSS_WITH_DES_CBC_SHA          uint16 = 0x0012
+	http2cipher_TLS_DHE_DSS_WITH_3DES_EDE_CBC_SHA     uint16 = 0x0013
+	http2cipher_TLS_DHE_RSA_EXPORT_WITH_DES40_CBC_SHA uint16 = 0x0014
+	http2cipher_TLS_DHE_RSA_WITH_DES_CBC_SHA          uint16 = 0x0015
+	http2cipher_TLS_DHE_RSA_WITH_3DES_EDE_CBC_SHA     uint16 = 0x0016
+	http2cipher_TLS_DH_anon_EXPORT_WITH_RC4_40_MD5    uint16 = 0x0017
+	http2cipher_TLS_DH_anon_WITH_RC4_128_MD5          uint16 = 0x0018
+	http2cipher_TLS_DH_anon_EXPORT_WITH_DES40_CBC_SHA uint16 = 0x0019
+	http2cipher_TLS_DH_anon_WITH_DES_CBC_SHA          uint16 = 0x001A
+	http2cipher_TLS_DH_anon_WITH_3DES_EDE_CBC_SHA     uint16 = 0x001B
+	// Reserved uint16 =  0x001C-1D
+	http2cipher_TLS_KRB5_WITH_DES_CBC_SHA             uint16 = 0x001E
+	http2cipher_TLS_KRB5_WITH_3DES_EDE_CBC_SHA        uint16 = 0x001F
+	http2cipher_TLS_KRB5_WITH_RC4_128_SHA             uint16 = 0x0020
+	http2cipher_TLS_KRB5_WITH_IDEA_CBC_SHA            uint16 = 0x0021
+	http2cipher_TLS_KRB5_WITH_DES_CBC_MD5             uint16 = 0x0022
+	http2cipher_TLS_KRB5_WITH_3DES_EDE_CBC_MD5        uint16 = 0x0023
+	http2cipher_TLS_KRB5_WITH_RC4_128_MD5             uint16 = 0x0024
+	http2cipher_TLS_KRB5_WITH_IDEA_CBC_MD5            uint16 = 0x0025
+	http2cipher_TLS_KRB5_EXPORT_WITH_DES_CBC_40_SHA   uint16 = 0x0026
+	http2cipher_TLS_KRB5_EXPORT_WITH_RC2_CBC_40_SHA   uint16 = 0x0027
+	http2cipher_TLS_KRB5_EXPORT_WITH_RC4_40_SHA       uint16 = 0x0028
+	http2cipher_TLS_KRB5_EXPORT_WITH_DES_CBC_40_MD5   uint16 = 0x0029
+	http2cipher_TLS_KRB5_EXPORT_WITH_RC2_CBC_40_MD5   uint16 = 0x002A
+	http2cipher_TLS_KRB5_EXPORT_WITH_RC4_40_MD5       uint16 = 0x002B
+	http2cipher_TLS_PSK_WITH_NULL_SHA                 uint16 = 0x002C
+	http2cipher_TLS_DHE_PSK_WITH_NULL_SHA             uint16 = 0x002D
+	http2cipher_TLS_RSA_PSK_WITH_NULL_SHA             uint16 = 0x002E
+	http2cipher_TLS_RSA_WITH_AES_128_CBC_SHA          uint16 = 0x002F
+	http2cipher_TLS_DH_DSS_WITH_AES_128_CBC_SHA       uint16 = 0x0030
+	http2cipher_TLS_DH_RSA_WITH_AES_128_CBC_SHA       uint16 = 0x0031
+	http2cipher_TLS_DHE_DSS_WITH_AES_128_CBC_SHA      uint16 = 0x0032
+	http2cipher_TLS_DHE_RSA_WITH_AES_128_CBC_SHA      uint16 = 0x0033
+	http2cipher_TLS_DH_anon_WITH_AES_128_CBC_SHA      uint16 = 0x0034
+	http2cipher_TLS_RSA_WITH_AES_256_CBC_SHA          uint16 = 0x0035
+	http2cipher_TLS_DH_DSS_WITH_AES_256_CBC_SHA       uint16 = 0x0036
+	http2cipher_TLS_DH_RSA_WITH_AES_256_CBC_SHA       uint16 = 0x0037
+	http2cipher_TLS_DHE_DSS_WITH_AES_256_CBC_SHA      uint16 = 0x0038
+	http2cipher_TLS_DHE_RSA_WITH_AES_256_CBC_SHA      uint16 = 0x0039
+	http2cipher_TLS_DH_anon_WITH_AES_256_CBC_SHA      uint16 = 0x003A
+	http2cipher_TLS_RSA_WITH_NULL_SHA256              uint16 = 0x003B
+	http2cipher_TLS_RSA_WITH_AES_128_CBC_SHA256       uint16 = 0x003C
+	http2cipher_TLS_RSA_WITH_AES_256_CBC_SHA256       uint16 = 0x003D
+	http2cipher_TLS_DH_DSS_WITH_AES_128_CBC_SHA256    uint16 = 0x003E
+	http2cipher_TLS_DH_RSA_WITH_AES_128_CBC_SHA256    uint16 = 0x003F
+	http2cipher_TLS_DHE_DSS_WITH_AES_128_CBC_SHA256   uint16 = 0x0040
+	http2cipher_TLS_RSA_WITH_CAMELLIA_128_CBC_SHA     uint16 = 0x0041
+	http2cipher_TLS_DH_DSS_WITH_CAMELLIA_128_CBC_SHA  uint16 = 0x0042
+	http2cipher_TLS_DH_RSA_WITH_CAMELLIA_128_CBC_SHA  uint16 = 0x0043
+	http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_128_CBC_SHA uint16 = 0x0044
+	http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_128_CBC_SHA uint16 = 0x0045
+	http2cipher_TLS_DH_anon_WITH_CAMELLIA_128_CBC_SHA uint16 = 0x0046
+	// Reserved uint16 =  0x0047-4F
+	// Reserved uint16 =  0x0050-58
+	// Reserved uint16 =  0x0059-5C
+	// Unassigned uint16 =  0x005D-5F
+	// Reserved uint16 =  0x0060-66
+	http2cipher_TLS_DHE_RSA_WITH_AES_128_CBC_SHA256 uint16 = 0x0067
+	http2cipher_TLS_DH_DSS_WITH_AES_256_CBC_SHA256  uint16 = 0x0068
+	http2cipher_TLS_DH_RSA_WITH_AES_256_CBC_SHA256  uint16 = 0x0069
+	http2cipher_TLS_DHE_DSS_WITH_AES_256_CBC_SHA256 uint16 = 0x006A
+	http2cipher_TLS_DHE_RSA_WITH_AES_256_CBC_SHA256 uint16 = 0x006B
+	http2cipher_TLS_DH_anon_WITH_AES_128_CBC_SHA256 uint16 = 0x006C
+	http2cipher_TLS_DH_anon_WITH_AES_256_CBC_SHA256 uint16 = 0x006D
+	// Unassigned uint16 =  0x006E-83
+	http2cipher_TLS_RSA_WITH_CAMELLIA_256_CBC_SHA        uint16 = 0x0084
+	http2cipher_TLS_DH_DSS_WITH_CAMELLIA_256_CBC_SHA     uint16 = 0x0085
+	http2cipher_TLS_DH_RSA_WITH_CAMELLIA_256_CBC_SHA     uint16 = 0x0086
+	http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_256_CBC_SHA    uint16 = 0x0087
+	http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_256_CBC_SHA    uint16 = 0x0088
+	http2cipher_TLS_DH_anon_WITH_CAMELLIA_256_CBC_SHA    uint16 = 0x0089
+	http2cipher_TLS_PSK_WITH_RC4_128_SHA                 uint16 = 0x008A
+	http2cipher_TLS_PSK_WITH_3DES_EDE_CBC_SHA            uint16 = 0x008B
+	http2cipher_TLS_PSK_WITH_AES_128_CBC_SHA             uint16 = 0x008C
+	http2cipher_TLS_PSK_WITH_AES_256_CBC_SHA             uint16 = 0x008D
+	http2cipher_TLS_DHE_PSK_WITH_RC4_128_SHA             uint16 = 0x008E
+	http2cipher_TLS_DHE_PSK_WITH_3DES_EDE_CBC_SHA        uint16 = 0x008F
+	http2cipher_TLS_DHE_PSK_WITH_AES_128_CBC_SHA         uint16 = 0x0090
+	http2cipher_TLS_DHE_PSK_WITH_AES_256_CBC_SHA         uint16 = 0x0091
+	http2cipher_TLS_RSA_PSK_WITH_RC4_128_SHA             uint16 = 0x0092
+	http2cipher_TLS_RSA_PSK_WITH_3DES_EDE_CBC_SHA        uint16 = 0x0093
+	http2cipher_TLS_RSA_PSK_WITH_AES_128_CBC_SHA         uint16 = 0x0094
+	http2cipher_TLS_RSA_PSK_WITH_AES_256_CBC_SHA         uint16 = 0x0095
+	http2cipher_TLS_RSA_WITH_SEED_CBC_SHA                uint16 = 0x0096
+	http2cipher_TLS_DH_DSS_WITH_SEED_CBC_SHA             uint16 = 0x0097
+	http2cipher_TLS_DH_RSA_WITH_SEED_CBC_SHA             uint16 = 0x0098
+	http2cipher_TLS_DHE_DSS_WITH_SEED_CBC_SHA            uint16 = 0x0099
+	http2cipher_TLS_DHE_RSA_WITH_SEED_CBC_SHA            uint16 = 0x009A
+	http2cipher_TLS_DH_anon_WITH_SEED_CBC_SHA            uint16 = 0x009B
+	http2cipher_TLS_RSA_WITH_AES_128_GCM_SHA256          uint16 = 0x009C
+	http2cipher_TLS_RSA_WITH_AES_256_GCM_SHA384          uint16 = 0x009D
+	http2cipher_TLS_DHE_RSA_WITH_AES_128_GCM_SHA256      uint16 = 0x009E
+	http2cipher_TLS_DHE_RSA_WITH_AES_256_GCM_SHA384      uint16 = 0x009F
+	http2cipher_TLS_DH_RSA_WITH_AES_128_GCM_SHA256       uint16 = 0x00A0
+	http2cipher_TLS_DH_RSA_WITH_AES_256_GCM_SHA384       uint16 = 0x00A1
+	http2cipher_TLS_DHE_DSS_WITH_AES_128_GCM_SHA256      uint16 = 0x00A2
+	http2cipher_TLS_DHE_DSS_WITH_AES_256_GCM_SHA384      uint16 = 0x00A3
+	http2cipher_TLS_DH_DSS_WITH_AES_128_GCM_SHA256       uint16 = 0x00A4
+	http2cipher_TLS_DH_DSS_WITH_AES_256_GCM_SHA384       uint16 = 0x00A5
+	http2cipher_TLS_DH_anon_WITH_AES_128_GCM_SHA256      uint16 = 0x00A6
+	http2cipher_TLS_DH_anon_WITH_AES_256_GCM_SHA384      uint16 = 0x00A7
+	http2cipher_TLS_PSK_WITH_AES_128_GCM_SHA256          uint16 = 0x00A8
+	http2cipher_TLS_PSK_WITH_AES_256_GCM_SHA384          uint16 = 0x00A9
+	http2cipher_TLS_DHE_PSK_WITH_AES_128_GCM_SHA256      uint16 = 0x00AA
+	http2cipher_TLS_DHE_PSK_WITH_AES_256_GCM_SHA384      uint16 = 0x00AB
+	http2cipher_TLS_RSA_PSK_WITH_AES_128_GCM_SHA256      uint16 = 0x00AC
+	http2cipher_TLS_RSA_PSK_WITH_AES_256_GCM_SHA384      uint16 = 0x00AD
+	http2cipher_TLS_PSK_WITH_AES_128_CBC_SHA256          uint16 = 0x00AE
+	http2cipher_TLS_PSK_WITH_AES_256_CBC_SHA384          uint16 = 0x00AF
+	http2cipher_TLS_PSK_WITH_NULL_SHA256                 uint16 = 0x00B0
+	http2cipher_TLS_PSK_WITH_NULL_SHA384                 uint16 = 0x00B1
+	http2cipher_TLS_DHE_PSK_WITH_AES_128_CBC_SHA256      uint16 = 0x00B2
+	http2cipher_TLS_DHE_PSK_WITH_AES_256_CBC_SHA384      uint16 = 0x00B3
+	http2cipher_TLS_DHE_PSK_WITH_NULL_SHA256             uint16 = 0x00B4
+	http2cipher_TLS_DHE_PSK_WITH_NULL_SHA384             uint16 = 0x00B5
+	http2cipher_TLS_RSA_PSK_WITH_AES_128_CBC_SHA256      uint16 = 0x00B6
+	http2cipher_TLS_RSA_PSK_WITH_AES_256_CBC_SHA384      uint16 = 0x00B7
+	http2cipher_TLS_RSA_PSK_WITH_NULL_SHA256             uint16 = 0x00B8
+	http2cipher_TLS_RSA_PSK_WITH_NULL_SHA384             uint16 = 0x00B9
+	http2cipher_TLS_RSA_WITH_CAMELLIA_128_CBC_SHA256     uint16 = 0x00BA
+	http2cipher_TLS_DH_DSS_WITH_CAMELLIA_128_CBC_SHA256  uint16 = 0x00BB
+	http2cipher_TLS_DH_RSA_WITH_CAMELLIA_128_CBC_SHA256  uint16 = 0x00BC
+	http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_128_CBC_SHA256 uint16 = 0x00BD
+	http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_128_CBC_SHA256 uint16 = 0x00BE
+	http2cipher_TLS_DH_anon_WITH_CAMELLIA_128_CBC_SHA256 uint16 = 0x00BF
+	http2cipher_TLS_RSA_WITH_CAMELLIA_256_CBC_SHA256     uint16 = 0x00C0
+	http2cipher_TLS_DH_DSS_WITH_CAMELLIA_256_CBC_SHA256  uint16 = 0x00C1
+	http2cipher_TLS_DH_RSA_WITH_CAMELLIA_256_CBC_SHA256  uint16 = 0x00C2
+	http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_256_CBC_SHA256 uint16 = 0x00C3
+	http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_256_CBC_SHA256 uint16 = 0x00C4
+	http2cipher_TLS_DH_anon_WITH_CAMELLIA_256_CBC_SHA256 uint16 = 0x00C5
+	// Unassigned uint16 =  0x00C6-FE
+	http2cipher_TLS_EMPTY_RENEGOTIATION_INFO_SCSV uint16 = 0x00FF
+	// Unassigned uint16 =  0x01-55,*
+	http2cipher_TLS_FALLBACK_SCSV uint16 = 0x5600
+	// Unassigned                                   uint16 = 0x5601 - 0xC000
+	http2cipher_TLS_ECDH_ECDSA_WITH_NULL_SHA                 uint16 = 0xC001
+	http2cipher_TLS_ECDH_ECDSA_WITH_RC4_128_SHA              uint16 = 0xC002
+	http2cipher_TLS_ECDH_ECDSA_WITH_3DES_EDE_CBC_SHA         uint16 = 0xC003
+	http2cipher_TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA          uint16 = 0xC004
+	http2cipher_TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA          uint16 = 0xC005
+	http2cipher_TLS_ECDHE_ECDSA_WITH_NULL_SHA                uint16 = 0xC006
+	http2cipher_TLS_ECDHE_ECDSA_WITH_RC4_128_SHA             uint16 = 0xC007
+	http2cipher_TLS_ECDHE_ECDSA_WITH_3DES_EDE_CBC_SHA        uint16 = 0xC008
+	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA         uint16 = 0xC009
+	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA         uint16 = 0xC00A
+	http2cipher_TLS_ECDH_RSA_WITH_NULL_SHA                   uint16 = 0xC00B
+	http2cipher_TLS_ECDH_RSA_WITH_RC4_128_SHA                uint16 = 0xC00C
+	http2cipher_TLS_ECDH_RSA_WITH_3DES_EDE_CBC_SHA           uint16 = 0xC00D
+	http2cipher_TLS_ECDH_RSA_WITH_AES_128_CBC_SHA            uint16 = 0xC00E
+	http2cipher_TLS_ECDH_RSA_WITH_AES_256_CBC_SHA            uint16 = 0xC00F
+	http2cipher_TLS_ECDHE_RSA_WITH_NULL_SHA                  uint16 = 0xC010
+	http2cipher_TLS_ECDHE_RSA_WITH_RC4_128_SHA               uint16 = 0xC011
+	http2cipher_TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA          uint16 = 0xC012
+	http2cipher_TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA           uint16 = 0xC013
+	http2cipher_TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA           uint16 = 0xC014
+	http2cipher_TLS_ECDH_anon_WITH_NULL_SHA                  uint16 = 0xC015
+	http2cipher_TLS_ECDH_anon_WITH_RC4_128_SHA               uint16 = 0xC016
+	http2cipher_TLS_ECDH_anon_WITH_3DES_EDE_CBC_SHA          uint16 = 0xC017
+	http2cipher_TLS_ECDH_anon_WITH_AES_128_CBC_SHA           uint16 = 0xC018
+	http2cipher_TLS_ECDH_anon_WITH_AES_256_CBC_SHA           uint16 = 0xC019
+	http2cipher_TLS_SRP_SHA_WITH_3DES_EDE_CBC_SHA            uint16 = 0xC01A
+	http2cipher_TLS_SRP_SHA_RSA_WITH_3DES_EDE_CBC_SHA        uint16 = 0xC01B
+	http2cipher_TLS_SRP_SHA_DSS_WITH_3DES_EDE_CBC_SHA        uint16 = 0xC01C
+	http2cipher_TLS_SRP_SHA_WITH_AES_128_CBC_SHA             uint16 = 0xC01D
+	http2cipher_TLS_SRP_SHA_RSA_WITH_AES_128_CBC_SHA         uint16 = 0xC01E
+	http2cipher_TLS_SRP_SHA_DSS_WITH_AES_128_CBC_SHA         uint16 = 0xC01F
+	http2cipher_TLS_SRP_SHA_WITH_AES_256_CBC_SHA             uint16 = 0xC020
+	http2cipher_TLS_SRP_SHA_RSA_WITH_AES_256_CBC_SHA         uint16 = 0xC021
+	http2cipher_TLS_SRP_SHA_DSS_WITH_AES_256_CBC_SHA         uint16 = 0xC022
+	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256      uint16 = 0xC023
+	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384      uint16 = 0xC024
+	http2cipher_TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA256       uint16 = 0xC025
+	http2cipher_TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA384       uint16 = 0xC026
+	http2cipher_TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256        uint16 = 0xC027
+	http2cipher_TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384        uint16 = 0xC028
+	http2cipher_TLS_ECDH_RSA_WITH_AES_128_CBC_SHA256         uint16 = 0xC029
+	http2cipher_TLS_ECDH_RSA_WITH_AES_256_CBC_SHA384         uint16 = 0xC02A
+	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256      uint16 = 0xC02B
+	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384      uint16 = 0xC02C
+	http2cipher_TLS_ECDH_ECDSA_WITH_AES_128_GCM_SHA256       uint16 = 0xC02D
+	http2cipher_TLS_ECDH_ECDSA_WITH_AES_256_GCM_SHA384       uint16 = 0xC02E
+	http2cipher_TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256        uint16 = 0xC02F
+	http2cipher_TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384        uint16 = 0xC030
+	http2cipher_TLS_ECDH_RSA_WITH_AES_128_GCM_SHA256         uint16 = 0xC031
+	http2cipher_TLS_ECDH_RSA_WITH_AES_256_GCM_SHA384         uint16 = 0xC032
+	http2cipher_TLS_ECDHE_PSK_WITH_RC4_128_SHA               uint16 = 0xC033
+	http2cipher_TLS_ECDHE_PSK_WITH_3DES_EDE_CBC_SHA          uint16 = 0xC034
+	http2cipher_TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA           uint16 = 0xC035
+	http2cipher_TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA           uint16 = 0xC036
+	http2cipher_TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA256        uint16 = 0xC037
+	http2cipher_TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA384        uint16 = 0xC038
+	http2cipher_TLS_ECDHE_PSK_WITH_NULL_SHA                  uint16 = 0xC039
+	http2cipher_TLS_ECDHE_PSK_WITH_NULL_SHA256               uint16 = 0xC03A
+	http2cipher_TLS_ECDHE_PSK_WITH_NULL_SHA384               uint16 = 0xC03B
+	http2cipher_TLS_RSA_WITH_ARIA_128_CBC_SHA256             uint16 = 0xC03C
+	http2cipher_TLS_RSA_WITH_ARIA_256_CBC_SHA384             uint16 = 0xC03D
+	http2cipher_TLS_DH_DSS_WITH_ARIA_128_CBC_SHA256          uint16 = 0xC03E
+	http2cipher_TLS_DH_DSS_WITH_ARIA_256_CBC_SHA384          uint16 = 0xC03F
+	http2cipher_TLS_DH_RSA_WITH_ARIA_128_CBC_SHA256          uint16 = 0xC040
+	http2cipher_TLS_DH_RSA_WITH_ARIA_256_CBC_SHA384          uint16 = 0xC041
+	http2cipher_TLS_DHE_DSS_WITH_ARIA_128_CBC_SHA256         uint16 = 0xC042
+	http2cipher_TLS_DHE_DSS_WITH_ARIA_256_CBC_SHA384         uint16 = 0xC043
+	http2cipher_TLS_DHE_RSA_WITH_ARIA_128_CBC_SHA256         uint16 = 0xC044
+	http2cipher_TLS_DHE_RSA_WITH_ARIA_256_CBC_SHA384         uint16 = 0xC045
+	http2cipher_TLS_DH_anon_WITH_ARIA_128_CBC_SHA256         uint16 = 0xC046
+	http2cipher_TLS_DH_anon_WITH_ARIA_256_CBC_SHA384         uint16 = 0xC047
+	http2cipher_TLS_ECDHE_ECDSA_WITH_ARIA_128_CBC_SHA256     uint16 = 0xC048
+	http2cipher_TLS_ECDHE_ECDSA_WITH_ARIA_256_CBC_SHA384     uint16 = 0xC049
+	http2cipher_TLS_ECDH_ECDSA_WITH_ARIA_128_CBC_SHA256      uint16 = 0xC04A
+	http2cipher_TLS_ECDH_ECDSA_WITH_ARIA_256_CBC_SHA384      uint16 = 0xC04B
+	http2cipher_TLS_ECDHE_RSA_WITH_ARIA_128_CBC_SHA256       uint16 = 0xC04C
+	http2cipher_TLS_ECDHE_RSA_WITH_ARIA_256_CBC_SHA384       uint16 = 0xC04D
+	http2cipher_TLS_ECDH_RSA_WITH_ARIA_128_CBC_SHA256        uint16 = 0xC04E
+	http2cipher_TLS_ECDH_RSA_WITH_ARIA_256_CBC_SHA384        uint16 = 0xC04F
+	http2cipher_TLS_RSA_WITH_ARIA_128_GCM_SHA256             uint16 = 0xC050
+	http2cipher_TLS_RSA_WITH_ARIA_256_GCM_SHA384             uint16 = 0xC051
+	http2cipher_TLS_DHE_RSA_WITH_ARIA_128_GCM_SHA256         uint16 = 0xC052
+	http2cipher_TLS_DHE_RSA_WITH_ARIA_256_GCM_SHA384         uint16 = 0xC053
+	http2cipher_TLS_DH_RSA_WITH_ARIA_128_GCM_SHA256          uint16 = 0xC054
+	http2cipher_TLS_DH_RSA_WITH_ARIA_256_GCM_SHA384          uint16 = 0xC055
+	http2cipher_TLS_DHE_DSS_WITH_ARIA_128_GCM_SHA256         uint16 = 0xC056
+	http2cipher_TLS_DHE_DSS_WITH_ARIA_256_GCM_SHA384         uint16 = 0xC057
+	http2cipher_TLS_DH_DSS_WITH_ARIA_128_GCM_SHA256          uint16 = 0xC058
+	http2cipher_TLS_DH_DSS_WITH_ARIA_256_GCM_SHA384          uint16 = 0xC059
+	http2cipher_TLS_DH_anon_WITH_ARIA_128_GCM_SHA256         uint16 = 0xC05A
+	http2cipher_TLS_DH_anon_WITH_ARIA_256_GCM_SHA384         uint16 = 0xC05B
+	http2cipher_TLS_ECDHE_ECDSA_WITH_ARIA_128_GCM_SHA256     uint16 = 0xC05C
+	http2cipher_TLS_ECDHE_ECDSA_WITH_ARIA_256_GCM_SHA384     uint16 = 0xC05D
+	http2cipher_TLS_ECDH_ECDSA_WITH_ARIA_128_GCM_SHA256      uint16 = 0xC05E
+	http2cipher_TLS_ECDH_ECDSA_WITH_ARIA_256_GCM_SHA384      uint16 = 0xC05F
+	http2cipher_TLS_ECDHE_RSA_WITH_ARIA_128_GCM_SHA256       uint16 = 0xC060
+	http2cipher_TLS_ECDHE_RSA_WITH_ARIA_256_GCM_SHA384       uint16 = 0xC061
+	http2cipher_TLS_ECDH_RSA_WITH_ARIA_128_GCM_SHA256        uint16 = 0xC062
+	http2cipher_TLS_ECDH_RSA_WITH_ARIA_256_GCM_SHA384        uint16 = 0xC063
+	http2cipher_TLS_PSK_WITH_ARIA_128_CBC_SHA256             uint16 = 0xC064
+	http2cipher_TLS_PSK_WITH_ARIA_256_CBC_SHA384             uint16 = 0xC065
+	http2cipher_TLS_DHE_PSK_WITH_ARIA_128_CBC_SHA256         uint16 = 0xC066
+	http2cipher_TLS_DHE_PSK_WITH_ARIA_256_CBC_SHA384         uint16 = 0xC067
+	http2cipher_TLS_RSA_PSK_WITH_ARIA_128_CBC_SHA256         uint16 = 0xC068
+	http2cipher_TLS_RSA_PSK_WITH_ARIA_256_CBC_SHA384         uint16 = 0xC069
+	http2cipher_TLS_PSK_WITH_ARIA_128_GCM_SHA256             uint16 = 0xC06A
+	http2cipher_TLS_PSK_WITH_ARIA_256_GCM_SHA384             uint16 = 0xC06B
+	http2cipher_TLS_DHE_PSK_WITH_ARIA_128_GCM_SHA256         uint16 = 0xC06C
+	http2cipher_TLS_DHE_PSK_WITH_ARIA_256_GCM_SHA384         uint16 = 0xC06D
+	http2cipher_TLS_RSA_PSK_WITH_ARIA_128_GCM_SHA256         uint16 = 0xC06E
+	http2cipher_TLS_RSA_PSK_WITH_ARIA_256_GCM_SHA384         uint16 = 0xC06F
+	http2cipher_TLS_ECDHE_PSK_WITH_ARIA_128_CBC_SHA256       uint16 = 0xC070
+	http2cipher_TLS_ECDHE_PSK_WITH_ARIA_256_CBC_SHA384       uint16 = 0xC071
+	http2cipher_TLS_ECDHE_ECDSA_WITH_CAMELLIA_128_CBC_SHA256 uint16 = 0xC072
+	http2cipher_TLS_ECDHE_ECDSA_WITH_CAMELLIA_256_CBC_SHA384 uint16 = 0xC073
+	http2cipher_TLS_ECDH_ECDSA_WITH_CAMELLIA_128_CBC_SHA256  uint16 = 0xC074
+	http2cipher_TLS_ECDH_ECDSA_WITH_CAMELLIA_256_CBC_SHA384  uint16 = 0xC075
+	http2cipher_TLS_ECDHE_RSA_WITH_CAMELLIA_128_CBC_SHA256   uint16 = 0xC076
+	http2cipher_TLS_ECDHE_RSA_WITH_CAMELLIA_256_CBC_SHA384   uint16 = 0xC077
+	http2cipher_TLS_ECDH_RSA_WITH_CAMELLIA_128_CBC_SHA256    uint16 = 0xC078
+	http2cipher_TLS_ECDH_RSA_WITH_CAMELLIA_256_CBC_SHA384    uint16 = 0xC079
+	http2cipher_TLS_RSA_WITH_CAMELLIA_128_GCM_SHA256         uint16 = 0xC07A
+	http2cipher_TLS_RSA_WITH_CAMELLIA_256_GCM_SHA384         uint16 = 0xC07B
+	http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_128_GCM_SHA256     uint16 = 0xC07C
+	http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_256_GCM_SHA384     uint16 = 0xC07D
+	http2cipher_TLS_DH_RSA_WITH_CAMELLIA_128_GCM_SHA256      uint16 = 0xC07E
+	http2cipher_TLS_DH_RSA_WITH_CAMELLIA_256_GCM_SHA384      uint16 = 0xC07F
+	http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_128_GCM_SHA256     uint16 = 0xC080
+	http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_256_GCM_SHA384     uint16 = 0xC081
+	http2cipher_TLS_DH_DSS_WITH_CAMELLIA_128_GCM_SHA256      uint16 = 0xC082
+	http2cipher_TLS_DH_DSS_WITH_CAMELLIA_256_GCM_SHA384      uint16 = 0xC083
+	http2cipher_TLS_DH_anon_WITH_CAMELLIA_128_GCM_SHA256     uint16 = 0xC084
+	http2cipher_TLS_DH_anon_WITH_CAMELLIA_256_GCM_SHA384     uint16 = 0xC085
+	http2cipher_TLS_ECDHE_ECDSA_WITH_CAMELLIA_128_GCM_SHA256 uint16 = 0xC086
+	http2cipher_TLS_ECDHE_ECDSA_WITH_CAMELLIA_256_GCM_SHA384 uint16 = 0xC087
+	http2cipher_TLS_ECDH_ECDSA_WITH_CAMELLIA_128_GCM_SHA256  uint16 = 0xC088
+	http2cipher_TLS_ECDH_ECDSA_WITH_CAMELLIA_256_GCM_SHA384  uint16 = 0xC089
+	http2cipher_TLS_ECDHE_RSA_WITH_CAMELLIA_128_GCM_SHA256   uint16 = 0xC08A
+	http2cipher_TLS_ECDHE_RSA_WITH_CAMELLIA_256_GCM_SHA384   uint16 = 0xC08B
+	http2cipher_TLS_ECDH_RSA_WITH_CAMELLIA_128_GCM_SHA256    uint16 = 0xC08C
+	http2cipher_TLS_ECDH_RSA_WITH_CAMELLIA_256_GCM_SHA384    uint16 = 0xC08D
+	http2cipher_TLS_PSK_WITH_CAMELLIA_128_GCM_SHA256         uint16 = 0xC08E
+	http2cipher_TLS_PSK_WITH_CAMELLIA_256_GCM_SHA384         uint16 = 0xC08F
+	http2cipher_TLS_DHE_PSK_WITH_CAMELLIA_128_GCM_SHA256     uint16 = 0xC090
+	http2cipher_TLS_DHE_PSK_WITH_CAMELLIA_256_GCM_SHA384     uint16 = 0xC091
+	http2cipher_TLS_RSA_PSK_WITH_CAMELLIA_128_GCM_SHA256     uint16 = 0xC092
+	http2cipher_TLS_RSA_PSK_WITH_CAMELLIA_256_GCM_SHA384     uint16 = 0xC093
+	http2cipher_TLS_PSK_WITH_CAMELLIA_128_CBC_SHA256         uint16 = 0xC094
+	http2cipher_TLS_PSK_WITH_CAMELLIA_256_CBC_SHA384         uint16 = 0xC095
+	http2cipher_TLS_DHE_PSK_WITH_CAMELLIA_128_CBC_SHA256     uint16 = 0xC096
+	http2cipher_TLS_DHE_PSK_WITH_CAMELLIA_256_CBC_SHA384     uint16 = 0xC097
+	http2cipher_TLS_RSA_PSK_WITH_CAMELLIA_128_CBC_SHA256     uint16 = 0xC098
+	http2cipher_TLS_RSA_PSK_WITH_CAMELLIA_256_CBC_SHA384     uint16 = 0xC099
+	http2cipher_TLS_ECDHE_PSK_WITH_CAMELLIA_128_CBC_SHA256   uint16 = 0xC09A
+	http2cipher_TLS_ECDHE_PSK_WITH_CAMELLIA_256_CBC_SHA384   uint16 = 0xC09B
+	http2cipher_TLS_RSA_WITH_AES_128_CCM                     uint16 = 0xC09C
+	http2cipher_TLS_RSA_WITH_AES_256_CCM                     uint16 = 0xC09D
+	http2cipher_TLS_DHE_RSA_WITH_AES_128_CCM                 uint16 = 0xC09E
+	http2cipher_TLS_DHE_RSA_WITH_AES_256_CCM                 uint16 = 0xC09F
+	http2cipher_TLS_RSA_WITH_AES_128_CCM_8                   uint16 = 0xC0A0
+	http2cipher_TLS_RSA_WITH_AES_256_CCM_8                   uint16 = 0xC0A1
+	http2cipher_TLS_DHE_RSA_WITH_AES_128_CCM_8               uint16 = 0xC0A2
+	http2cipher_TLS_DHE_RSA_WITH_AES_256_CCM_8               uint16 = 0xC0A3
+	http2cipher_TLS_PSK_WITH_AES_128_CCM                     uint16 = 0xC0A4
+	http2cipher_TLS_PSK_WITH_AES_256_CCM                     uint16 = 0xC0A5
+	http2cipher_TLS_DHE_PSK_WITH_AES_128_CCM                 uint16 = 0xC0A6
+	http2cipher_TLS_DHE_PSK_WITH_AES_256_CCM                 uint16 = 0xC0A7
+	http2cipher_TLS_PSK_WITH_AES_128_CCM_8                   uint16 = 0xC0A8
+	http2cipher_TLS_PSK_WITH_AES_256_CCM_8                   uint16 = 0xC0A9
+	http2cipher_TLS_PSK_DHE_WITH_AES_128_CCM_8               uint16 = 0xC0AA
+	http2cipher_TLS_PSK_DHE_WITH_AES_256_CCM_8               uint16 = 0xC0AB
+	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_128_CCM             uint16 = 0xC0AC
+	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_256_CCM             uint16 = 0xC0AD
+	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_128_CCM_8           uint16 = 0xC0AE
+	http2cipher_TLS_ECDHE_ECDSA_WITH_AES_256_CCM_8           uint16 = 0xC0AF
+	// Unassigned uint16 =  0xC0B0-FF
+	// Unassigned uint16 =  0xC1-CB,*
+	// Unassigned uint16 =  0xCC00-A7
+	http2cipher_TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256   uint16 = 0xCCA8
+	http2cipher_TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 uint16 = 0xCCA9
+	http2cipher_TLS_DHE_RSA_WITH_CHACHA20_POLY1305_SHA256     uint16 = 0xCCAA
+	http2cipher_TLS_PSK_WITH_CHACHA20_POLY1305_SHA256         uint16 = 0xCCAB
+	http2cipher_TLS_ECDHE_PSK_WITH_CHACHA20_POLY1305_SHA256   uint16 = 0xCCAC
+	http2cipher_TLS_DHE_PSK_WITH_CHACHA20_POLY1305_SHA256     uint16 = 0xCCAD
+	http2cipher_TLS_RSA_PSK_WITH_CHACHA20_POLY1305_SHA256     uint16 = 0xCCAE
+)
+
+// isBadCipher reports whether the cipher is blacklisted by the HTTP/2 spec.
+// References:
+// https://tools.ietf.org/html/rfc7540#appendix-A
+// Reject cipher suites from Appendix A.
+// "This list includes those cipher suites that do not
+// offer an ephemeral key exchange and those that are
+// based on the TLS null, stream or block cipher type"
+func http2isBadCipher(cipher uint16) bool {
+	switch cipher {
+	case http2cipher_TLS_NULL_WITH_NULL_NULL,
+		http2cipher_TLS_RSA_WITH_NULL_MD5,
+		http2cipher_TLS_RSA_WITH_NULL_SHA,
+		http2cipher_TLS_RSA_EXPORT_WITH_RC4_40_MD5,
+		http2cipher_TLS_RSA_WITH_RC4_128_MD5,
+		http2cipher_TLS_RSA_WITH_RC4_128_SHA,
+		http2cipher_TLS_RSA_EXPORT_WITH_RC2_CBC_40_MD5,
+		http2cipher_TLS_RSA_WITH_IDEA_CBC_SHA,
+		http2cipher_TLS_RSA_EXPORT_WITH_DES40_CBC_SHA,
+		http2cipher_TLS_RSA_WITH_DES_CBC_SHA,
+		http2cipher_TLS_RSA_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_DH_DSS_EXPORT_WITH_DES40_CBC_SHA,
+		http2cipher_TLS_DH_DSS_WITH_DES_CBC_SHA,
+		http2cipher_TLS_DH_DSS_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_DH_RSA_EXPORT_WITH_DES40_CBC_SHA,
+		http2cipher_TLS_DH_RSA_WITH_DES_CBC_SHA,
+		http2cipher_TLS_DH_RSA_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_DHE_DSS_EXPORT_WITH_DES40_CBC_SHA,
+		http2cipher_TLS_DHE_DSS_WITH_DES_CBC_SHA,
+		http2cipher_TLS_DHE_DSS_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_DHE_RSA_EXPORT_WITH_DES40_CBC_SHA,
+		http2cipher_TLS_DHE_RSA_WITH_DES_CBC_SHA,
+		http2cipher_TLS_DHE_RSA_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_DH_anon_EXPORT_WITH_RC4_40_MD5,
+		http2cipher_TLS_DH_anon_WITH_RC4_128_MD5,
+		http2cipher_TLS_DH_anon_EXPORT_WITH_DES40_CBC_SHA,
+		http2cipher_TLS_DH_anon_WITH_DES_CBC_SHA,
+		http2cipher_TLS_DH_anon_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_KRB5_WITH_DES_CBC_SHA,
+		http2cipher_TLS_KRB5_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_KRB5_WITH_RC4_128_SHA,
+		http2cipher_TLS_KRB5_WITH_IDEA_CBC_SHA,
+		http2cipher_TLS_KRB5_WITH_DES_CBC_MD5,
+		http2cipher_TLS_KRB5_WITH_3DES_EDE_CBC_MD5,
+		http2cipher_TLS_KRB5_WITH_RC4_128_MD5,
+		http2cipher_TLS_KRB5_WITH_IDEA_CBC_MD5,
+		http2cipher_TLS_KRB5_EXPORT_WITH_DES_CBC_40_SHA,
+		http2cipher_TLS_KRB5_EXPORT_WITH_RC2_CBC_40_SHA,
+		http2cipher_TLS_KRB5_EXPORT_WITH_RC4_40_SHA,
+		http2cipher_TLS_KRB5_EXPORT_WITH_DES_CBC_40_MD5,
+		http2cipher_TLS_KRB5_EXPORT_WITH_RC2_CBC_40_MD5,
+		http2cipher_TLS_KRB5_EXPORT_WITH_RC4_40_MD5,
+		http2cipher_TLS_PSK_WITH_NULL_SHA,
+		http2cipher_TLS_DHE_PSK_WITH_NULL_SHA,
+		http2cipher_TLS_RSA_PSK_WITH_NULL_SHA,
+		http2cipher_TLS_RSA_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_DH_DSS_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_DH_RSA_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_DHE_DSS_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_DHE_RSA_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_DH_anon_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_RSA_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_DH_DSS_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_DH_RSA_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_DHE_DSS_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_DHE_RSA_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_DH_anon_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_RSA_WITH_NULL_SHA256,
+		http2cipher_TLS_RSA_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_RSA_WITH_AES_256_CBC_SHA256,
+		http2cipher_TLS_DH_DSS_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_DH_RSA_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_DHE_DSS_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_RSA_WITH_CAMELLIA_128_CBC_SHA,
+		http2cipher_TLS_DH_DSS_WITH_CAMELLIA_128_CBC_SHA,
+		http2cipher_TLS_DH_RSA_WITH_CAMELLIA_128_CBC_SHA,
+		http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_128_CBC_SHA,
+		http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_128_CBC_SHA,
+		http2cipher_TLS_DH_anon_WITH_CAMELLIA_128_CBC_SHA,
+		http2cipher_TLS_DHE_RSA_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_DH_DSS_WITH_AES_256_CBC_SHA256,
+		http2cipher_TLS_DH_RSA_WITH_AES_256_CBC_SHA256,
+		http2cipher_TLS_DHE_DSS_WITH_AES_256_CBC_SHA256,
+		http2cipher_TLS_DHE_RSA_WITH_AES_256_CBC_SHA256,
+		http2cipher_TLS_DH_anon_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_DH_anon_WITH_AES_256_CBC_SHA256,
+		http2cipher_TLS_RSA_WITH_CAMELLIA_256_CBC_SHA,
+		http2cipher_TLS_DH_DSS_WITH_CAMELLIA_256_CBC_SHA,
+		http2cipher_TLS_DH_RSA_WITH_CAMELLIA_256_CBC_SHA,
+		http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_256_CBC_SHA,
+		http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_256_CBC_SHA,
+		http2cipher_TLS_DH_anon_WITH_CAMELLIA_256_CBC_SHA,
+		http2cipher_TLS_PSK_WITH_RC4_128_SHA,
+		http2cipher_TLS_PSK_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_PSK_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_PSK_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_DHE_PSK_WITH_RC4_128_SHA,
+		http2cipher_TLS_DHE_PSK_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_DHE_PSK_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_DHE_PSK_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_RSA_PSK_WITH_RC4_128_SHA,
+		http2cipher_TLS_RSA_PSK_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_RSA_PSK_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_RSA_PSK_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_RSA_WITH_SEED_CBC_SHA,
+		http2cipher_TLS_DH_DSS_WITH_SEED_CBC_SHA,
+		http2cipher_TLS_DH_RSA_WITH_SEED_CBC_SHA,
+		http2cipher_TLS_DHE_DSS_WITH_SEED_CBC_SHA,
+		http2cipher_TLS_DHE_RSA_WITH_SEED_CBC_SHA,
+		http2cipher_TLS_DH_anon_WITH_SEED_CBC_SHA,
+		http2cipher_TLS_RSA_WITH_AES_128_GCM_SHA256,
+		http2cipher_TLS_RSA_WITH_AES_256_GCM_SHA384,
+		http2cipher_TLS_DH_RSA_WITH_AES_128_GCM_SHA256,
+		http2cipher_TLS_DH_RSA_WITH_AES_256_GCM_SHA384,
+		http2cipher_TLS_DH_DSS_WITH_AES_128_GCM_SHA256,
+		http2cipher_TLS_DH_DSS_WITH_AES_256_GCM_SHA384,
+		http2cipher_TLS_DH_anon_WITH_AES_128_GCM_SHA256,
+		http2cipher_TLS_DH_anon_WITH_AES_256_GCM_SHA384,
+		http2cipher_TLS_PSK_WITH_AES_128_GCM_SHA256,
+		http2cipher_TLS_PSK_WITH_AES_256_GCM_SHA384,
+		http2cipher_TLS_RSA_PSK_WITH_AES_128_GCM_SHA256,
+		http2cipher_TLS_RSA_PSK_WITH_AES_256_GCM_SHA384,
+		http2cipher_TLS_PSK_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_PSK_WITH_AES_256_CBC_SHA384,
+		http2cipher_TLS_PSK_WITH_NULL_SHA256,
+		http2cipher_TLS_PSK_WITH_NULL_SHA384,
+		http2cipher_TLS_DHE_PSK_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_DHE_PSK_WITH_AES_256_CBC_SHA384,
+		http2cipher_TLS_DHE_PSK_WITH_NULL_SHA256,
+		http2cipher_TLS_DHE_PSK_WITH_NULL_SHA384,
+		http2cipher_TLS_RSA_PSK_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_RSA_PSK_WITH_AES_256_CBC_SHA384,
+		http2cipher_TLS_RSA_PSK_WITH_NULL_SHA256,
+		http2cipher_TLS_RSA_PSK_WITH_NULL_SHA384,
+		http2cipher_TLS_RSA_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_DH_DSS_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_DH_RSA_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_DH_anon_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_RSA_WITH_CAMELLIA_256_CBC_SHA256,
+		http2cipher_TLS_DH_DSS_WITH_CAMELLIA_256_CBC_SHA256,
+		http2cipher_TLS_DH_RSA_WITH_CAMELLIA_256_CBC_SHA256,
+		http2cipher_TLS_DHE_DSS_WITH_CAMELLIA_256_CBC_SHA256,
+		http2cipher_TLS_DHE_RSA_WITH_CAMELLIA_256_CBC_SHA256,
+		http2cipher_TLS_DH_anon_WITH_CAMELLIA_256_CBC_SHA256,
+		http2cipher_TLS_EMPTY_RENEGOTIATION_INFO_SCSV,
+		http2cipher_TLS_ECDH_ECDSA_WITH_NULL_SHA,
+		http2cipher_TLS_ECDH_ECDSA_WITH_RC4_128_SHA,
+		http2cipher_TLS_ECDH_ECDSA_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_ECDHE_ECDSA_WITH_NULL_SHA,
+		http2cipher_TLS_ECDHE_ECDSA_WITH_RC4_128_SHA,
+		http2cipher_TLS_ECDHE_ECDSA_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_ECDH_RSA_WITH_NULL_SHA,
+		http2cipher_TLS_ECDH_RSA_WITH_RC4_128_SHA,
+		http2cipher_TLS_ECDH_RSA_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_ECDH_RSA_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_ECDH_RSA_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_ECDHE_RSA_WITH_NULL_SHA,
+		http2cipher_TLS_ECDHE_RSA_WITH_RC4_128_SHA,
+		http2cipher_TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_ECDH_anon_WITH_NULL_SHA,
+		http2cipher_TLS_ECDH_anon_WITH_RC4_128_SHA,
+		http2cipher_TLS_ECDH_anon_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_ECDH_anon_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_ECDH_anon_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_SRP_SHA_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_SRP_SHA_RSA_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_SRP_SHA_DSS_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_SRP_SHA_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_SRP_SHA_RSA_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_SRP_SHA_DSS_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_SRP_SHA_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_SRP_SHA_RSA_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_SRP_SHA_DSS_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384,
+		http2cipher_TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA384,
+		http2cipher_TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384,
+		http2cipher_TLS_ECDH_RSA_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_ECDH_RSA_WITH_AES_256_CBC_SHA384,
+		http2cipher_TLS_ECDH_ECDSA_WITH_AES_128_GCM_SHA256,
+		http2cipher_TLS_ECDH_ECDSA_WITH_AES_256_GCM_SHA384,
+		http2cipher_TLS_ECDH_RSA_WITH_AES_128_GCM_SHA256,
+		http2cipher_TLS_ECDH_RSA_WITH_AES_256_GCM_SHA384,
+		http2cipher_TLS_ECDHE_PSK_WITH_RC4_128_SHA,
+		http2cipher_TLS_ECDHE_PSK_WITH_3DES_EDE_CBC_SHA,
+		http2cipher_TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA,
+		http2cipher_TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA,
+		http2cipher_TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA256,
+		http2cipher_TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA384,
+		http2cipher_TLS_ECDHE_PSK_WITH_NULL_SHA,
+		http2cipher_TLS_ECDHE_PSK_WITH_NULL_SHA256,
+		http2cipher_TLS_ECDHE_PSK_WITH_NULL_SHA384,
+		http2cipher_TLS_RSA_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_RSA_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_DH_DSS_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_DH_DSS_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_DH_RSA_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_DH_RSA_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_DHE_DSS_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_DHE_DSS_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_DHE_RSA_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_DHE_RSA_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_DH_anon_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_DH_anon_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_ECDHE_ECDSA_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_ECDHE_ECDSA_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_ECDH_ECDSA_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_ECDH_ECDSA_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_ECDHE_RSA_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_ECDHE_RSA_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_ECDH_RSA_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_ECDH_RSA_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_RSA_WITH_ARIA_128_GCM_SHA256,
+		http2cipher_TLS_RSA_WITH_ARIA_256_GCM_SHA384,
+		http2cipher_TLS_DH_RSA_WITH_ARIA_128_GCM_SHA256,
+		http2cipher_TLS_DH_RSA_WITH_ARIA_256_GCM_SHA384,
+		http2cipher_TLS_DH_DSS_WITH_ARIA_128_GCM_SHA256,
+		http2cipher_TLS_DH_DSS_WITH_ARIA_256_GCM_SHA384,
+		http2cipher_TLS_DH_anon_WITH_ARIA_128_GCM_SHA256,
+		http2cipher_TLS_DH_anon_WITH_ARIA_256_GCM_SHA384,
+		http2cipher_TLS_ECDH_ECDSA_WITH_ARIA_128_GCM_SHA256,
+		http2cipher_TLS_ECDH_ECDSA_WITH_ARIA_256_GCM_SHA384,
+		http2cipher_TLS_ECDH_RSA_WITH_ARIA_128_GCM_SHA256,
+		http2cipher_TLS_ECDH_RSA_WITH_ARIA_256_GCM_SHA384,
+		http2cipher_TLS_PSK_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_PSK_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_DHE_PSK_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_DHE_PSK_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_RSA_PSK_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_RSA_PSK_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_PSK_WITH_ARIA_128_GCM_SHA256,
+		http2cipher_TLS_PSK_WITH_ARIA_256_GCM_SHA384,
+		http2cipher_TLS_RSA_PSK_WITH_ARIA_128_GCM_SHA256,
+		http2cipher_TLS_RSA_PSK_WITH_ARIA_256_GCM_SHA384,
+		http2cipher_TLS_ECDHE_PSK_WITH_ARIA_128_CBC_SHA256,
+		http2cipher_TLS_ECDHE_PSK_WITH_ARIA_256_CBC_SHA384,
+		http2cipher_TLS_ECDHE_ECDSA_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_ECDHE_ECDSA_WITH_CAMELLIA_256_CBC_SHA384,
+		http2cipher_TLS_ECDH_ECDSA_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_ECDH_ECDSA_WITH_CAMELLIA_256_CBC_SHA384,
+		http2cipher_TLS_ECDHE_RSA_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_ECDHE_RSA_WITH_CAMELLIA_256_CBC_SHA384,
+		http2cipher_TLS_ECDH_RSA_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_ECDH_RSA_WITH_CAMELLIA_256_CBC_SHA384,
+		http2cipher_TLS_RSA_WITH_CAMELLIA_128_GCM_SHA256,
+		http2cipher_TLS_RSA_WITH_CAMELLIA_256_GCM_SHA384,
+		http2cipher_TLS_DH_RSA_WITH_CAMELLIA_128_GCM_SHA256,
+		http2cipher_TLS_DH_RSA_WITH_CAMELLIA_256_GCM_SHA384,
+		http2cipher_TLS_DH_DSS_WITH_CAMELLIA_128_GCM_SHA256,
+		http2cipher_TLS_DH_DSS_WITH_CAMELLIA_256_GCM_SHA384,
+		http2cipher_TLS_DH_anon_WITH_CAMELLIA_128_GCM_SHA256,
+		http2cipher_TLS_DH_anon_WITH_CAMELLIA_256_GCM_SHA384,
+		http2cipher_TLS_ECDH_ECDSA_WITH_CAMELLIA_128_GCM_SHA256,
+		http2cipher_TLS_ECDH_ECDSA_WITH_CAMELLIA_256_GCM_SHA384,
+		http2cipher_TLS_ECDH_RSA_WITH_CAMELLIA_128_GCM_SHA256,
+		http2cipher_TLS_ECDH_RSA_WITH_CAMELLIA_256_GCM_SHA384,
+		http2cipher_TLS_PSK_WITH_CAMELLIA_128_GCM_SHA256,
+		http2cipher_TLS_PSK_WITH_CAMELLIA_256_GCM_SHA384,
+		http2cipher_TLS_RSA_PSK_WITH_CAMELLIA_128_GCM_SHA256,
+		http2cipher_TLS_RSA_PSK_WITH_CAMELLIA_256_GCM_SHA384,
+		http2cipher_TLS_PSK_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_PSK_WITH_CAMELLIA_256_CBC_SHA384,
+		http2cipher_TLS_DHE_PSK_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_DHE_PSK_WITH_CAMELLIA_256_CBC_SHA384,
+		http2cipher_TLS_RSA_PSK_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_RSA_PSK_WITH_CAMELLIA_256_CBC_SHA384,
+		http2cipher_TLS_ECDHE_PSK_WITH_CAMELLIA_128_CBC_SHA256,
+		http2cipher_TLS_ECDHE_PSK_WITH_CAMELLIA_256_CBC_SHA384,
+		http2cipher_TLS_RSA_WITH_AES_128_CCM,
+		http2cipher_TLS_RSA_WITH_AES_256_CCM,
+		http2cipher_TLS_RSA_WITH_AES_128_CCM_8,
+		http2cipher_TLS_RSA_WITH_AES_256_CCM_8,
+		http2cipher_TLS_PSK_WITH_AES_128_CCM,
+		http2cipher_TLS_PSK_WITH_AES_256_CCM,
+		http2cipher_TLS_PSK_WITH_AES_128_CCM_8,
+		http2cipher_TLS_PSK_WITH_AES_256_CCM_8:
+		return true
+	default:
+		return false
+	}
+}
+
+// ClientConnPool manages a pool of HTTP/2 client connections.
+type http2ClientConnPool interface {
+	// GetClientConn returns a specific HTTP/2 connection (usually
+	// a TLS-TCP connection) to an HTTP/2 server. On success, the
+	// returned ClientConn accounts for the upcoming RoundTrip
+	// call, so the caller should not omit it. If the caller needs
+	// to, ClientConn.RoundTrip can be called with a bogus
+	// new(http.Request) to release the stream reservation.
+	GetClientConn(req *Request, addr string) (*http2ClientConn, error)
+	MarkDead(*http2ClientConn)
+}
+
+// clientConnPoolIdleCloser is the interface implemented by ClientConnPool
+// implementations which can close their idle connections.
+type http2clientConnPoolIdleCloser interface {
+	http2ClientConnPool
+	closeIdleConnections()
+}
+
+var (
+	_ http2clientConnPoolIdleCloser = (*http2clientConnPool)(nil)
+	_ http2clientConnPoolIdleCloser = http2noDialClientConnPool{}
+)
+
+// TODO: use singleflight for dialing and addConnCalls?
+type http2clientConnPool struct {
+	t *http2Transport
+
+	mu sync.Mutex // TODO: maybe switch to RWMutex
+	// TODO: add support for sharing conns based on cert names
+	// (e.g. share conn for googleapis.com and appspot.com)
+	conns        map[string][]*http2ClientConn // key is host:port
+	dialing      map[string]*http2dialCall     // currently in-flight dials
+	keys         map[*http2ClientConn][]string
+	addConnCalls map[string]*http2addConnCall // in-flight addConnIfNeeded calls
+}
+
+func (p *http2clientConnPool) GetClientConn(req *Request, addr string) (*http2ClientConn, error) {
+	return p.getClientConn(req, addr, http2dialOnMiss)
+}
+
+const (
+	http2dialOnMiss   = true
+	http2noDialOnMiss = false
+)
+
+func (p *http2clientConnPool) getClientConn(req *Request, addr string, dialOnMiss bool) (*http2ClientConn, error) {
+	// TODO(dneil): Dial a new connection when t.DisableKeepAlives is set?
+	if http2isConnectionCloseRequest(req) && dialOnMiss {
+		// It gets its own connection.
+		http2traceGetConn(req, addr)
+		const singleUse = true
+		cc, err := p.t.dialClientConn(req.Context(), addr, singleUse)
+		if err != nil {
+			return nil, err
+		}
+		return cc, nil
+	}
+	for {
+		p.mu.Lock()
+		for _, cc := range p.conns[addr] {
+			if cc.ReserveNewRequest() {
+				// When a connection is presented to us by the net/http package,
+				// the GetConn hook has already been called.
+				// Don't call it a second time here.
+				if !cc.getConnCalled {
+					http2traceGetConn(req, addr)
+				}
+				cc.getConnCalled = false
+				p.mu.Unlock()
+				return cc, nil
+			}
+		}
+		if !dialOnMiss {
+			p.mu.Unlock()
+			return nil, http2ErrNoCachedConn
+		}
+		http2traceGetConn(req, addr)
+		call := p.getStartDialLocked(req.Context(), addr)
+		p.mu.Unlock()
+		<-call.done
+		if http2shouldRetryDial(call, req) {
+			continue
+		}
+		cc, err := call.res, call.err
+		if err != nil {
+			return nil, err
+		}
+		if cc.ReserveNewRequest() {
+			return cc, nil
+		}
+	}
+}
+
+// dialCall is an in-flight Transport dial call to a host.
+type http2dialCall struct {
+	_ http2incomparable
+	p *http2clientConnPool
+	// the context associated with the request
+	// that created this dialCall
+	ctx  context.Context
+	done chan struct{}    // closed when done
+	res  *http2ClientConn // valid after done is closed
+	err  error            // valid after done is closed
+}
+
+// requires p.mu is held.
+func (p *http2clientConnPool) getStartDialLocked(ctx context.Context, addr string) *http2dialCall {
+	if call, ok := p.dialing[addr]; ok {
+		// A dial is already in-flight. Don't start another.
+		return call
+	}
+	call := &http2dialCall{p: p, done: make(chan struct{}), ctx: ctx}
+	if p.dialing == nil {
+		p.dialing = make(map[string]*http2dialCall)
+	}
+	p.dialing[addr] = call
+	go call.dial(call.ctx, addr)
+	return call
+}
+
+// run in its own goroutine.
+func (c *http2dialCall) dial(ctx context.Context, addr string) {
+	const singleUse = false // shared conn
+	c.res, c.err = c.p.t.dialClientConn(ctx, addr, singleUse)
+	close(c.done)
+
+	c.p.mu.Lock()
+	delete(c.p.dialing, addr)
+	if c.err == nil {
+		c.p.addConnLocked(addr, c.res)
+	}
+	c.p.mu.Unlock()
+}
+
+// addConnIfNeeded makes a NewClientConn out of c if a connection for key doesn't
+// already exist. It coalesces concurrent calls with the same key.
+// This is used by the http1 Transport code when it creates a new connection. Because
+// the http1 Transport doesn't de-dup TCP dials to outbound hosts (because it doesn't know
+// the protocol), it can get into a situation where it has multiple TLS connections.
+// This code decides which ones live or die.
+// The return value used is whether c was used.
+// c is never closed.
+func (p *http2clientConnPool) addConnIfNeeded(key string, t *http2Transport, c *tls.Conn) (used bool, err error) {
+	p.mu.Lock()
+	for _, cc := range p.conns[key] {
+		if cc.CanTakeNewRequest() {
+			p.mu.Unlock()
+			return false, nil
+		}
+	}
+	call, dup := p.addConnCalls[key]
+	if !dup {
+		if p.addConnCalls == nil {
+			p.addConnCalls = make(map[string]*http2addConnCall)
+		}
+		call = &http2addConnCall{
+			p:    p,
+			done: make(chan struct{}),
+		}
+		p.addConnCalls[key] = call
+		go call.run(t, key, c)
+	}
+	p.mu.Unlock()
+
+	<-call.done
+	if call.err != nil {
+		return false, call.err
+	}
+	return !dup, nil
+}
+
+type http2addConnCall struct {
+	_    http2incomparable
+	p    *http2clientConnPool
+	done chan struct{} // closed when done
+	err  error
+}
+
+func (c *http2addConnCall) run(t *http2Transport, key string, tc *tls.Conn) {
+	cc, err := t.NewClientConn(tc)
+
+	p := c.p
+	p.mu.Lock()
+	if err != nil {
+		c.err = err
+	} else {
+		cc.getConnCalled = true // already called by the net/http package
+		p.addConnLocked(key, cc)
+	}
+	delete(p.addConnCalls, key)
+	p.mu.Unlock()
+	close(c.done)
+}
+
+// p.mu must be held
+func (p *http2clientConnPool) addConnLocked(key string, cc *http2ClientConn) {
+	for _, v := range p.conns[key] {
+		if v == cc {
+			return
+		}
+	}
+	if p.conns == nil {
+		p.conns = make(map[string][]*http2ClientConn)
+	}
+	if p.keys == nil {
+		p.keys = make(map[*http2ClientConn][]string)
+	}
+	p.conns[key] = append(p.conns[key], cc)
+	p.keys[cc] = append(p.keys[cc], key)
+}
+
+func (p *http2clientConnPool) MarkDead(cc *http2ClientConn) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	for _, key := range p.keys[cc] {
+		vv, ok := p.conns[key]
+		if !ok {
+			continue
+		}
+		newList := http2filterOutClientConn(vv, cc)
+		if len(newList) > 0 {
+			p.conns[key] = newList
+		} else {
+			delete(p.conns, key)
+		}
+	}
+	delete(p.keys, cc)
+}
+
+func (p *http2clientConnPool) closeIdleConnections() {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	// TODO: don't close a cc if it was just added to the pool
+	// milliseconds ago and has never been used. There's currently
+	// a small race window with the HTTP/1 Transport's integration
+	// where it can add an idle conn just before using it, and
+	// somebody else can concurrently call CloseIdleConns and
+	// break some caller's RoundTrip.
+	for _, vv := range p.conns {
+		for _, cc := range vv {
+			cc.closeIfIdle()
+		}
+	}
+}
+
+func http2filterOutClientConn(in []*http2ClientConn, exclude *http2ClientConn) []*http2ClientConn {
+	out := in[:0]
+	for _, v := range in {
+		if v != exclude {
+			out = append(out, v)
+		}
+	}
+	// If we filtered it out, zero out the last item to prevent
+	// the GC from seeing it.
+	if len(in) != len(out) {
+		in[len(in)-1] = nil
+	}
+	return out
+}
+
+// noDialClientConnPool is an implementation of http2.ClientConnPool
+// which never dials. We let the HTTP/1.1 client dial and use its TLS
+// connection instead.
+type http2noDialClientConnPool struct{ *http2clientConnPool }
+
+func (p http2noDialClientConnPool) GetClientConn(req *Request, addr string) (*http2ClientConn, error) {
+	return p.getClientConn(req, addr, http2noDialOnMiss)
+}
+
+// shouldRetryDial reports whether the current request should
+// retry dialing after the call finished unsuccessfully, for example
+// if the dial was canceled because of a context cancellation or
+// deadline expiry.
+func http2shouldRetryDial(call *http2dialCall, req *Request) bool {
+	if call.err == nil {
+		// No error, no need to retry
+		return false
+	}
+	if call.ctx == req.Context() {
+		// If the call has the same context as the request, the dial
+		// should not be retried, since any cancellation will have come
+		// from this request.
+		return false
+	}
+	if !errors.Is(call.err, context.Canceled) && !errors.Is(call.err, context.DeadlineExceeded) {
+		// If the call error is not because of a context cancellation or a deadline expiry,
+		// the dial should not be retried.
+		return false
+	}
+	// Only retry if the error is a context cancellation error or deadline expiry
+	// and the context associated with the call was canceled or expired.
+	return call.ctx.Err() != nil
+}
+
+// Buffer chunks are allocated from a pool to reduce pressure on GC.
+// The maximum wasted space per dataBuffer is 2x the largest size class,
+// which happens when the dataBuffer has multiple chunks and there is
+// one unread byte in both the first and last chunks. We use a few size
+// classes to minimize overheads for servers that typically receive very
+// small request bodies.
+//
+// TODO: Benchmark to determine if the pools are necessary. The GC may have
+// improved enough that we can instead allocate chunks like this:
+// make([]byte, max(16<<10, expectedBytesRemaining))
+var (
+	http2dataChunkSizeClasses = []int{
+		1 << 10,
+		2 << 10,
+		4 << 10,
+		8 << 10,
+		16 << 10,
+	}
+	http2dataChunkPools = [...]sync.Pool{
+		{New: func() interface{} { return make([]byte, 1<<10) }},
+		{New: func() interface{} { return make([]byte, 2<<10) }},
+		{New: func() interface{} { return make([]byte, 4<<10) }},
+		{New: func() interface{} { return make([]byte, 8<<10) }},
+		{New: func() interface{} { return make([]byte, 16<<10) }},
+	}
+)
+
+func http2getDataBufferChunk(size int64) []byte {
+	i := 0
+	for ; i < len(http2dataChunkSizeClasses)-1; i++ {
+		if size <= int64(http2dataChunkSizeClasses[i]) {
+			break
+		}
+	}
+	return http2dataChunkPools[i].Get().([]byte)
+}
+
+func http2putDataBufferChunk(p []byte) {
+	for i, n := range http2dataChunkSizeClasses {
+		if len(p) == n {
+			http2dataChunkPools[i].Put(p)
+			return
+		}
+	}
+	panic(fmt.Sprintf("unexpected buffer len=%v", len(p)))
+}
+
+// dataBuffer is an io.ReadWriter backed by a list of data chunks.
+// Each dataBuffer is used to read DATA frames on a single stream.
+// The buffer is divided into chunks so the server can limit the
+// total memory used by a single connection without limiting the
+// request body size on any single stream.
+type http2dataBuffer struct {
+	chunks   [][]byte
+	r        int   // next byte to read is chunks[0][r]
+	w        int   // next byte to write is chunks[len(chunks)-1][w]
+	size     int   // total buffered bytes
+	expected int64 // we expect at least this many bytes in future Write calls (ignored if <= 0)
+}
+
+var http2errReadEmpty = errors.New("read from empty dataBuffer")
+
+// Read copies bytes from the buffer into p.
+// It is an error to read when no data is available.
+func (b *http2dataBuffer) Read(p []byte) (int, error) {
+	if b.size == 0 {
+		return 0, http2errReadEmpty
+	}
+	var ntotal int
+	for len(p) > 0 && b.size > 0 {
+		readFrom := b.bytesFromFirstChunk()
+		n := copy(p, readFrom)
+		p = p[n:]
+		ntotal += n
+		b.r += n
+		b.size -= n
+		// If the first chunk has been consumed, advance to the next chunk.
+		if b.r == len(b.chunks[0]) {
+			http2putDataBufferChunk(b.chunks[0])
+			end := len(b.chunks) - 1
+			copy(b.chunks[:end], b.chunks[1:])
+			b.chunks[end] = nil
+			b.chunks = b.chunks[:end]
+			b.r = 0
+		}
+	}
+	return ntotal, nil
+}
+
+func (b *http2dataBuffer) bytesFromFirstChunk() []byte {
+	if len(b.chunks) == 1 {
+		return b.chunks[0][b.r:b.w]
+	}
+	return b.chunks[0][b.r:]
+}
+
+// Len returns the number of bytes of the unread portion of the buffer.
+func (b *http2dataBuffer) Len() int {
+	return b.size
+}
+
+// Write appends p to the buffer.
+func (b *http2dataBuffer) Write(p []byte) (int, error) {
+	ntotal := len(p)
+	for len(p) > 0 {
+		// If the last chunk is empty, allocate a new chunk. Try to allocate
+		// enough to fully copy p plus any additional bytes we expect to
+		// receive. However, this may allocate less than len(p).
+		want := int64(len(p))
+		if b.expected > want {
+			want = b.expected
+		}
+		chunk := b.lastChunkOrAlloc(want)
+		n := copy(chunk[b.w:], p)
+		p = p[n:]
+		b.w += n
+		b.size += n
+		b.expected -= int64(n)
+	}
+	return ntotal, nil
+}
+
+func (b *http2dataBuffer) lastChunkOrAlloc(want int64) []byte {
+	if len(b.chunks) != 0 {
+		last := b.chunks[len(b.chunks)-1]
+		if b.w < len(last) {
+			return last
+		}
+	}
+	chunk := http2getDataBufferChunk(want)
+	b.chunks = append(b.chunks, chunk)
+	b.w = 0
+	return chunk
+}
+
+// An ErrCode is an unsigned 32-bit error code as defined in the HTTP/2 spec.
+type http2ErrCode uint32
+
+const (
+	http2ErrCodeNo                 http2ErrCode = 0x0
+	http2ErrCodeProtocol           http2ErrCode = 0x1
+	http2ErrCodeInternal           http2ErrCode = 0x2
+	http2ErrCodeFlowControl        http2ErrCode = 0x3
+	http2ErrCodeSettingsTimeout    http2ErrCode = 0x4
+	http2ErrCodeStreamClosed       http2ErrCode = 0x5
+	http2ErrCodeFrameSize          http2ErrCode = 0x6
+	http2ErrCodeRefusedStream      http2ErrCode = 0x7
+	http2ErrCodeCancel             http2ErrCode = 0x8
+	http2ErrCodeCompression        http2ErrCode = 0x9
+	http2ErrCodeConnect            http2ErrCode = 0xa
+	http2ErrCodeEnhanceYourCalm    http2ErrCode = 0xb
+	http2ErrCodeInadequateSecurity http2ErrCode = 0xc
+	http2ErrCodeHTTP11Required     http2ErrCode = 0xd
+)
+
+var http2errCodeName = map[http2ErrCode]string{
+	http2ErrCodeNo:                 "NO_ERROR",
+	http2ErrCodeProtocol:           "PROTOCOL_ERROR",
+	http2ErrCodeInternal:           "INTERNAL_ERROR",
+	http2ErrCodeFlowControl:        "FLOW_CONTROL_ERROR",
+	http2ErrCodeSettingsTimeout:    "SETTINGS_TIMEOUT",
+	http2ErrCodeStreamClosed:       "STREAM_CLOSED",
+	http2ErrCodeFrameSize:          "FRAME_SIZE_ERROR",
+	http2ErrCodeRefusedStream:      "REFUSED_STREAM",
+	http2ErrCodeCancel:             "CANCEL",
+	http2ErrCodeCompression:        "COMPRESSION_ERROR",
+	http2ErrCodeConnect:            "CONNECT_ERROR",
+	http2ErrCodeEnhanceYourCalm:    "ENHANCE_YOUR_CALM",
+	http2ErrCodeInadequateSecurity: "INADEQUATE_SECURITY",
+	http2ErrCodeHTTP11Required:     "HTTP_1_1_REQUIRED",
+}
+
+func (e http2ErrCode) String() string {
+	if s, ok := http2errCodeName[e]; ok {
+		return s
+	}
+	return fmt.Sprintf("unknown error code 0x%x", uint32(e))
+}
+
+func (e http2ErrCode) stringToken() string {
+	if s, ok := http2errCodeName[e]; ok {
+		return s
+	}
+	return fmt.Sprintf("ERR_UNKNOWN_%d", uint32(e))
+}
+
+// ConnectionError is an error that results in the termination of the
+// entire connection.
+type http2ConnectionError http2ErrCode
+
+func (e http2ConnectionError) Error() string {
+	return fmt.Sprintf("connection error: %s", http2ErrCode(e))
+}
+
+// StreamError is an error that only affects one stream within an
+// HTTP/2 connection.
+type http2StreamError struct {
+	StreamID uint32
+	Code     http2ErrCode
+	Cause    error // optional additional detail
+}
+
+// errFromPeer is a sentinel error value for StreamError.Cause to
+// indicate that the StreamError was sent from the peer over the wire
+// and wasn't locally generated in the Transport.
+var http2errFromPeer = errors.New("received from peer")
+
+func http2streamError(id uint32, code http2ErrCode) http2StreamError {
+	return http2StreamError{StreamID: id, Code: code}
+}
+
+func (e http2StreamError) Error() string {
+	if e.Cause != nil {
+		return fmt.Sprintf("stream error: stream ID %d; %v; %v", e.StreamID, e.Code, e.Cause)
+	}
+	return fmt.Sprintf("stream error: stream ID %d; %v", e.StreamID, e.Code)
+}
+
+// 6.9.1 The Flow Control Window
+// "If a sender receives a WINDOW_UPDATE that causes a flow control
+// window to exceed this maximum it MUST terminate either the stream
+// or the connection, as appropriate. For streams, [...]; for the
+// connection, a GOAWAY frame with a FLOW_CONTROL_ERROR code."
+type http2goAwayFlowError struct{}
+
+func (http2goAwayFlowError) Error() string { return "connection exceeded flow control window size" }
+
+// connError represents an HTTP/2 ConnectionError error code, along
+// with a string (for debugging) explaining why.
+//
+// Errors of this type are only returned by the frame parser functions
+// and converted into ConnectionError(Code), after stashing away
+// the Reason into the Framer's errDetail field, accessible via
+// the (*Framer).ErrorDetail method.
+type http2connError struct {
+	Code   http2ErrCode // the ConnectionError error code
+	Reason string       // additional reason
+}
+
+func (e http2connError) Error() string {
+	return fmt.Sprintf("http2: connection error: %v: %v", e.Code, e.Reason)
+}
+
+type http2pseudoHeaderError string
+
+func (e http2pseudoHeaderError) Error() string {
+	return fmt.Sprintf("invalid pseudo-header %q", string(e))
+}
+
+type http2duplicatePseudoHeaderError string
+
+func (e http2duplicatePseudoHeaderError) Error() string {
+	return fmt.Sprintf("duplicate pseudo-header %q", string(e))
+}
+
+type http2headerFieldNameError string
+
+func (e http2headerFieldNameError) Error() string {
+	return fmt.Sprintf("invalid header field name %q", string(e))
+}
+
+type http2headerFieldValueError string
+
+func (e http2headerFieldValueError) Error() string {
+	return fmt.Sprintf("invalid header field value for %q", string(e))
+}
+
+var (
+	http2errMixPseudoHeaderTypes = errors.New("mix of request and response pseudo headers")
+	http2errPseudoAfterRegular   = errors.New("pseudo header field after regular")
+)
+
+// flow is the flow control window's size.
+type http2flow struct {
+	_ http2incomparable
+
+	// n is the number of DATA bytes we're allowed to send.
+	// A flow is kept both on a conn and a per-stream.
+	n int32
+
+	// conn points to the shared connection-level flow that is
+	// shared by all streams on that conn. It is nil for the flow
+	// that's on the conn directly.
+	conn *http2flow
+}
+
+func (f *http2flow) setConnFlow(cf *http2flow) { f.conn = cf }
+
+func (f *http2flow) available() int32 {
+	n := f.n
+	if f.conn != nil && f.conn.n < n {
+		n = f.conn.n
+	}
+	return n
+}
+
+func (f *http2flow) take(n int32) {
+	if n > f.available() {
+		panic("internal error: took too much")
+	}
+	f.n -= n
+	if f.conn != nil {
+		f.conn.n -= n
+	}
+}
+
+// add adds n bytes (positive or negative) to the flow control window.
+// It returns false if the sum would exceed 2^31-1.
+func (f *http2flow) add(n int32) bool {
+	sum := f.n + n
+	if (sum > n) == (f.n > 0) {
+		f.n = sum
+		return true
+	}
+	return false
+}
+
+const http2frameHeaderLen = 9
+
+var http2padZeros = make([]byte, 255) // zeros for padding
+
+// A FrameType is a registered frame type as defined in
+// http://http2.github.io/http2-spec/#rfc.section.11.2
+type http2FrameType uint8
+
+const (
+	http2FrameData         http2FrameType = 0x0
+	http2FrameHeaders      http2FrameType = 0x1
+	http2FramePriority     http2FrameType = 0x2
+	http2FrameRSTStream    http2FrameType = 0x3
+	http2FrameSettings     http2FrameType = 0x4
+	http2FramePushPromise  http2FrameType = 0x5
+	http2FramePing         http2FrameType = 0x6
+	http2FrameGoAway       http2FrameType = 0x7
+	http2FrameWindowUpdate http2FrameType = 0x8
+	http2FrameContinuation http2FrameType = 0x9
+)
+
+var http2frameName = map[http2FrameType]string{
+	http2FrameData:         "DATA",
+	http2FrameHeaders:      "HEADERS",
+	http2FramePriority:     "PRIORITY",
+	http2FrameRSTStream:    "RST_STREAM",
+	http2FrameSettings:     "SETTINGS",
+	http2FramePushPromise:  "PUSH_PROMISE",
+	http2FramePing:         "PING",
+	http2FrameGoAway:       "GOAWAY",
+	http2FrameWindowUpdate: "WINDOW_UPDATE",
+	http2FrameContinuation: "CONTINUATION",
+}
+
+func (t http2FrameType) String() string {
+	if s, ok := http2frameName[t]; ok {
+		return s
+	}
+	return fmt.Sprintf("UNKNOWN_FRAME_TYPE_%d", uint8(t))
+}
+
+// Flags is a bitmask of HTTP/2 flags.
+// The meaning of flags varies depending on the frame type.
+type http2Flags uint8
+
+// Has reports whether f contains all (0 or more) flags in v.
+func (f http2Flags) Has(v http2Flags) bool {
+	return (f & v) == v
+}
+
+// Frame-specific FrameHeader flag bits.
+const (
+	// Data Frame
+	http2FlagDataEndStream http2Flags = 0x1
+	http2FlagDataPadded    http2Flags = 0x8
+
+	// Headers Frame
+	http2FlagHeadersEndStream  http2Flags = 0x1
+	http2FlagHeadersEndHeaders http2Flags = 0x4
+	http2FlagHeadersPadded     http2Flags = 0x8
+	http2FlagHeadersPriority   http2Flags = 0x20
+
+	// Settings Frame
+	http2FlagSettingsAck http2Flags = 0x1
+
+	// Ping Frame
+	http2FlagPingAck http2Flags = 0x1
+
+	// Continuation Frame
+	http2FlagContinuationEndHeaders http2Flags = 0x4
+
+	http2FlagPushPromiseEndHeaders http2Flags = 0x4
+	http2FlagPushPromisePadded     http2Flags = 0x8
+)
+
+var http2flagName = map[http2FrameType]map[http2Flags]string{
+	http2FrameData: {
+		http2FlagDataEndStream: "END_STREAM",
+		http2FlagDataPadded:    "PADDED",
+	},
+	http2FrameHeaders: {
+		http2FlagHeadersEndStream:  "END_STREAM",
+		http2FlagHeadersEndHeaders: "END_HEADERS",
+		http2FlagHeadersPadded:     "PADDED",
+		http2FlagHeadersPriority:   "PRIORITY",
+	},
+	http2FrameSettings: {
+		http2FlagSettingsAck: "ACK",
+	},
+	http2FramePing: {
+		http2FlagPingAck: "ACK",
+	},
+	http2FrameContinuation: {
+		http2FlagContinuationEndHeaders: "END_HEADERS",
+	},
+	http2FramePushPromise: {
+		http2FlagPushPromiseEndHeaders: "END_HEADERS",
+		http2FlagPushPromisePadded:     "PADDED",
+	},
+}
+
+// a frameParser parses a frame given its FrameHeader and payload
+// bytes. The length of payload will always equal fh.Length (which
+// might be 0).
+type http2frameParser func(fc *http2frameCache, fh http2FrameHeader, countError func(string), payload []byte) (http2Frame, error)
+
+var http2frameParsers = map[http2FrameType]http2frameParser{
+	http2FrameData:         http2parseDataFrame,
+	http2FrameHeaders:      http2parseHeadersFrame,
+	http2FramePriority:     http2parsePriorityFrame,
+	http2FrameRSTStream:    http2parseRSTStreamFrame,
+	http2FrameSettings:     http2parseSettingsFrame,
+	http2FramePushPromise:  http2parsePushPromise,
+	http2FramePing:         http2parsePingFrame,
+	http2FrameGoAway:       http2parseGoAwayFrame,
+	http2FrameWindowUpdate: http2parseWindowUpdateFrame,
+	http2FrameContinuation: http2parseContinuationFrame,
+}
+
+func http2typeFrameParser(t http2FrameType) http2frameParser {
+	if f := http2frameParsers[t]; f != nil {
+		return f
+	}
+	return http2parseUnknownFrame
+}
+
+// A FrameHeader is the 9 byte header of all HTTP/2 frames.
+//
+// See http://http2.github.io/http2-spec/#FrameHeader
+type http2FrameHeader struct {
+	valid bool // caller can access []byte fields in the Frame
+
+	// Type is the 1 byte frame type. There are ten standard frame
+	// types, but extension frame types may be written by WriteRawFrame
+	// and will be returned by ReadFrame (as UnknownFrame).
+	Type http2FrameType
+
+	// Flags are the 1 byte of 8 potential bit flags per frame.
+	// They are specific to the frame type.
+	Flags http2Flags
+
+	// Length is the length of the frame, not including the 9 byte header.
+	// The maximum size is one byte less than 16MB (uint24), but only
+	// frames up to 16KB are allowed without peer agreement.
+	Length uint32
+
+	// StreamID is which stream this frame is for. Certain frames
+	// are not stream-specific, in which case this field is 0.
+	StreamID uint32
+}
+
+// Header returns h. It exists so FrameHeaders can be embedded in other
+// specific frame types and implement the Frame interface.
+func (h http2FrameHeader) Header() http2FrameHeader { return h }
+
+func (h http2FrameHeader) String() string {
+	var buf bytes.Buffer
+	buf.WriteString("[FrameHeader ")
+	h.writeDebug(&buf)
+	buf.WriteByte(']')
+	return buf.String()
+}
+
+func (h http2FrameHeader) writeDebug(buf *bytes.Buffer) {
+	buf.WriteString(h.Type.String())
+	if h.Flags != 0 {
+		buf.WriteString(" flags=")
+		set := 0
+		for i := uint8(0); i < 8; i++ {
+			if h.Flags&(1<<i) == 0 {
+				continue
+			}
+			set++
+			if set > 1 {
+				buf.WriteByte('|')
+			}
+			name := http2flagName[h.Type][http2Flags(1<<i)]
+			if name != "" {
+				buf.WriteString(name)
+			} else {
+				fmt.Fprintf(buf, "0x%x", 1<<i)
+			}
+		}
+	}
+	if h.StreamID != 0 {
+		fmt.Fprintf(buf, " stream=%d", h.StreamID)
+	}
+	fmt.Fprintf(buf, " len=%d", h.Length)
+}
+
+func (h *http2FrameHeader) checkValid() {
+	if !h.valid {
+		panic("Frame accessor called on non-owned Frame")
+	}
+}
+
+func (h *http2FrameHeader) invalidate() { h.valid = false }
+
+// frame header bytes.
+// Used only by ReadFrameHeader.
+var http2fhBytes = sync.Pool{
+	New: func() interface{} {
+		buf := make([]byte, http2frameHeaderLen)
+		return &buf
+	},
+}
+
+// ReadFrameHeader reads 9 bytes from r and returns a FrameHeader.
+// Most users should use Framer.ReadFrame instead.
+func http2ReadFrameHeader(r io.Reader) (http2FrameHeader, error) {
+	bufp := http2fhBytes.Get().(*[]byte)
+	defer http2fhBytes.Put(bufp)
+	return http2readFrameHeader(*bufp, r)
+}
+
+func http2readFrameHeader(buf []byte, r io.Reader) (http2FrameHeader, error) {
+	_, err := io.ReadFull(r, buf[:http2frameHeaderLen])
+	if err != nil {
+		return http2FrameHeader{}, err
+	}
+	return http2FrameHeader{
+		Length:   (uint32(buf[0])<<16 | uint32(buf[1])<<8 | uint32(buf[2])),
+		Type:     http2FrameType(buf[3]),
+		Flags:    http2Flags(buf[4]),
+		StreamID: binary.BigEndian.Uint32(buf[5:]) & (1<<31 - 1),
+		valid:    true,
+	}, nil
+}
+
+// A Frame is the base interface implemented by all frame types.
+// Callers will generally type-assert the specific frame type:
+// *HeadersFrame, *SettingsFrame, *WindowUpdateFrame, etc.
+//
+// Frames are only valid until the next call to Framer.ReadFrame.
+type http2Frame interface {
+	Header() http2FrameHeader
+
+	// invalidate is called by Framer.ReadFrame to make this
+	// frame's buffers as being invalid, since the subsequent
+	// frame will reuse them.
+	invalidate()
+}
+
+// A Framer reads and writes Frames.
+type http2Framer struct {
+	r         io.Reader
+	lastFrame http2Frame
+	errDetail error
+
+	// countError is a non-nil func that's called on a frame parse
+	// error with some unique error path token. It's initialized
+	// from Transport.CountError or Server.CountError.
+	countError func(errToken string)
+
+	// lastHeaderStream is non-zero if the last frame was an
+	// unfinished HEADERS/CONTINUATION.
+	lastHeaderStream uint32
+
+	maxReadSize uint32
+	headerBuf   [http2frameHeaderLen]byte
+
+	// TODO: let getReadBuf be configurable, and use a less memory-pinning
+	// allocator in server.go to minimize memory pinned for many idle conns.
+	// Will probably also need to make frame invalidation have a hook too.
+	getReadBuf func(size uint32) []byte
+	readBuf    []byte // cache for default getReadBuf
+
+	maxWriteSize uint32 // zero means unlimited; TODO: implement
+
+	w    io.Writer
+	wbuf []byte
+
+	// AllowIllegalWrites permits the Framer's Write methods to
+	// write frames that do not conform to the HTTP/2 spec. This
+	// permits using the Framer to test other HTTP/2
+	// implementations' conformance to the spec.
+	// If false, the Write methods will prefer to return an error
+	// rather than comply.
+	AllowIllegalWrites bool
+
+	// AllowIllegalReads permits the Framer's ReadFrame method
+	// to return non-compliant frames or frame orders.
+	// This is for testing and permits using the Framer to test
+	// other HTTP/2 implementations' conformance to the spec.
+	// It is not compatible with ReadMetaHeaders.
+	AllowIllegalReads bool
+
+	// ReadMetaHeaders if non-nil causes ReadFrame to merge
+	// HEADERS and CONTINUATION frames together and return
+	// MetaHeadersFrame instead.
+	ReadMetaHeaders *hpack.Decoder
+
+	// MaxHeaderListSize is the http2 MAX_HEADER_LIST_SIZE.
+	// It's used only if ReadMetaHeaders is set; 0 means a sane default
+	// (currently 16MB)
+	// If the limit is hit, MetaHeadersFrame.Truncated is set true.
+	MaxHeaderListSize uint32
+
+	// TODO: track which type of frame & with which flags was sent
+	// last. Then return an error (unless AllowIllegalWrites) if
+	// we're in the middle of a header block and a
+	// non-Continuation or Continuation on a different stream is
+	// attempted to be written.
+
+	logReads, logWrites bool
+
+	debugFramer       *http2Framer // only use for logging written writes
+	debugFramerBuf    *bytes.Buffer
+	debugReadLoggerf  func(string, ...interface{})
+	debugWriteLoggerf func(string, ...interface{})
+
+	frameCache *http2frameCache // nil if frames aren't reused (default)
+}
+
+func (fr *http2Framer) maxHeaderListSize() uint32 {
+	if fr.MaxHeaderListSize == 0 {
+		return 16 << 20 // sane default, per docs
+	}
+	return fr.MaxHeaderListSize
+}
+
+func (f *http2Framer) startWrite(ftype http2FrameType, flags http2Flags, streamID uint32) {
+	// Write the FrameHeader.
+	f.wbuf = append(f.wbuf[:0],
+		0, // 3 bytes of length, filled in in endWrite
+		0,
+		0,
+		byte(ftype),
+		byte(flags),
+		byte(streamID>>24),
+		byte(streamID>>16),
+		byte(streamID>>8),
+		byte(streamID))
+}
+
+func (f *http2Framer) endWrite() error {
+	// Now that we know the final size, fill in the FrameHeader in
+	// the space previously reserved for it. Abuse append.
+	length := len(f.wbuf) - http2frameHeaderLen
+	if length >= (1 << 24) {
+		return http2ErrFrameTooLarge
+	}
+	_ = append(f.wbuf[:0],
+		byte(length>>16),
+		byte(length>>8),
+		byte(length))
+	if f.logWrites {
+		f.logWrite()
+	}
+
+	n, err := f.w.Write(f.wbuf)
+	if err == nil && n != len(f.wbuf) {
+		err = io.ErrShortWrite
+	}
+	return err
+}
+
+func (f *http2Framer) logWrite() {
+	if f.debugFramer == nil {
+		f.debugFramerBuf = new(bytes.Buffer)
+		f.debugFramer = http2NewFramer(nil, f.debugFramerBuf)
+		f.debugFramer.logReads = false // we log it ourselves, saying "wrote" below
+		// Let us read anything, even if we accidentally wrote it
+		// in the wrong order:
+		f.debugFramer.AllowIllegalReads = true
+	}
+	f.debugFramerBuf.Write(f.wbuf)
+	fr, err := f.debugFramer.ReadFrame()
+	if err != nil {
+		f.debugWriteLoggerf("http2: Framer %p: failed to decode just-written frame", f)
+		return
+	}
+	f.debugWriteLoggerf("http2: Framer %p: wrote %v", f, http2summarizeFrame(fr))
+}
+
+func (f *http2Framer) writeByte(v byte) { f.wbuf = append(f.wbuf, v) }
+
+func (f *http2Framer) writeBytes(v []byte) { f.wbuf = append(f.wbuf, v...) }
+
+func (f *http2Framer) writeUint16(v uint16) { f.wbuf = append(f.wbuf, byte(v>>8), byte(v)) }
+
+func (f *http2Framer) writeUint32(v uint32) {
+	f.wbuf = append(f.wbuf, byte(v>>24), byte(v>>16), byte(v>>8), byte(v))
+}
+
+const (
+	http2minMaxFrameSize = 1 << 14
+	http2maxFrameSize    = 1<<24 - 1
+)
+
+// SetReuseFrames allows the Framer to reuse Frames.
+// If called on a Framer, Frames returned by calls to ReadFrame are only
+// valid until the next call to ReadFrame.
+func (fr *http2Framer) SetReuseFrames() {
+	if fr.frameCache != nil {
+		return
+	}
+	fr.frameCache = &http2frameCache{}
+}
+
+type http2frameCache struct {
+	dataFrame http2DataFrame
+}
+
+func (fc *http2frameCache) getDataFrame() *http2DataFrame {
+	if fc == nil {
+		return &http2DataFrame{}
+	}
+	return &fc.dataFrame
+}
+
+// NewFramer returns a Framer that writes frames to w and reads them from r.
+func http2NewFramer(w io.Writer, r io.Reader) *http2Framer {
+	fr := &http2Framer{
+		w:                 w,
+		r:                 r,
+		countError:        func(string) {},
+		logReads:          http2logFrameReads,
+		logWrites:         http2logFrameWrites,
+		debugReadLoggerf:  log.Printf,
+		debugWriteLoggerf: log.Printf,
+	}
+	fr.getReadBuf = func(size uint32) []byte {
+		if cap(fr.readBuf) >= int(size) {
+			return fr.readBuf[:size]
+		}
+		fr.readBuf = make([]byte, size)
+		return fr.readBuf
+	}
+	fr.SetMaxReadFrameSize(http2maxFrameSize)
+	return fr
+}
+
+// SetMaxReadFrameSize sets the maximum size of a frame
+// that will be read by a subsequent call to ReadFrame.
+// It is the caller's responsibility to advertise this
+// limit with a SETTINGS frame.
+func (fr *http2Framer) SetMaxReadFrameSize(v uint32) {
+	if v > http2maxFrameSize {
+		v = http2maxFrameSize
+	}
+	fr.maxReadSize = v
+}
+
+// ErrorDetail returns a more detailed error of the last error
+// returned by Framer.ReadFrame. For instance, if ReadFrame
+// returns a StreamError with code PROTOCOL_ERROR, ErrorDetail
+// will say exactly what was invalid. ErrorDetail is not guaranteed
+// to return a non-nil value and like the rest of the http2 package,
+// its return value is not protected by an API compatibility promise.
+// ErrorDetail is reset after the next call to ReadFrame.
+func (fr *http2Framer) ErrorDetail() error {
+	return fr.errDetail
+}
+
+// ErrFrameTooLarge is returned from Framer.ReadFrame when the peer
+// sends a frame that is larger than declared with SetMaxReadFrameSize.
+var http2ErrFrameTooLarge = errors.New("http2: frame too large")
+
+// terminalReadFrameError reports whether err is an unrecoverable
+// error from ReadFrame and no other frames should be read.
+func http2terminalReadFrameError(err error) bool {
+	if _, ok := err.(http2StreamError); ok {
+		return false
+	}
+	return err != nil
+}
+
+// ReadFrame reads a single frame. The returned Frame is only valid
+// until the next call to ReadFrame.
+//
+// If the frame is larger than previously set with SetMaxReadFrameSize, the
+// returned error is ErrFrameTooLarge. Other errors may be of type
+// ConnectionError, StreamError, or anything else from the underlying
+// reader.
+func (fr *http2Framer) ReadFrame() (http2Frame, error) {
+	fr.errDetail = nil
+	if fr.lastFrame != nil {
+		fr.lastFrame.invalidate()
+	}
+	fh, err := http2readFrameHeader(fr.headerBuf[:], fr.r)
+	if err != nil {
+		return nil, err
+	}
+	if fh.Length > fr.maxReadSize {
+		return nil, http2ErrFrameTooLarge
+	}
+	payload := fr.getReadBuf(fh.Length)
+	if _, err := io.ReadFull(fr.r, payload); err != nil {
+		return nil, err
+	}
+	f, err := http2typeFrameParser(fh.Type)(fr.frameCache, fh, fr.countError, payload)
+	if err != nil {
+		if ce, ok := err.(http2connError); ok {
+			return nil, fr.connError(ce.Code, ce.Reason)
+		}
+		return nil, err
+	}
+	if err := fr.checkFrameOrder(f); err != nil {
+		return nil, err
+	}
+	if fr.logReads {
+		fr.debugReadLoggerf("http2: Framer %p: read %v", fr, http2summarizeFrame(f))
+	}
+	if fh.Type == http2FrameHeaders && fr.ReadMetaHeaders != nil {
+		return fr.readMetaFrame(f.(*http2HeadersFrame))
+	}
+	return f, nil
+}
+
+// connError returns ConnectionError(code) but first
+// stashes away a public reason to the caller can optionally relay it
+// to the peer before hanging up on them. This might help others debug
+// their implementations.
+func (fr *http2Framer) connError(code http2ErrCode, reason string) error {
+	fr.errDetail = errors.New(reason)
+	return http2ConnectionError(code)
+}
+
+// checkFrameOrder reports an error if f is an invalid frame to return
+// next from ReadFrame. Mostly it checks whether HEADERS and
+// CONTINUATION frames are contiguous.
+func (fr *http2Framer) checkFrameOrder(f http2Frame) error {
+	last := fr.lastFrame
+	fr.lastFrame = f
+	if fr.AllowIllegalReads {
+		return nil
+	}
+
+	fh := f.Header()
+	if fr.lastHeaderStream != 0 {
+		if fh.Type != http2FrameContinuation {
+			return fr.connError(http2ErrCodeProtocol,
+				fmt.Sprintf("got %s for stream %d; expected CONTINUATION following %s for stream %d",
+					fh.Type, fh.StreamID,
+					last.Header().Type, fr.lastHeaderStream))
+		}
+		if fh.StreamID != fr.lastHeaderStream {
+			return fr.connError(http2ErrCodeProtocol,
+				fmt.Sprintf("got CONTINUATION for stream %d; expected stream %d",
+					fh.StreamID, fr.lastHeaderStream))
+		}
+	} else if fh.Type == http2FrameContinuation {
+		return fr.connError(http2ErrCodeProtocol, fmt.Sprintf("unexpected CONTINUATION for stream %d", fh.StreamID))
+	}
+
+	switch fh.Type {
+	case http2FrameHeaders, http2FrameContinuation:
+		if fh.Flags.Has(http2FlagHeadersEndHeaders) {
+			fr.lastHeaderStream = 0
+		} else {
+			fr.lastHeaderStream = fh.StreamID
+		}
+	}
+
+	return nil
+}
+
+// A DataFrame conveys arbitrary, variable-length sequences of octets
+// associated with a stream.
+// See http://http2.github.io/http2-spec/#rfc.section.6.1
+type http2DataFrame struct {
+	http2FrameHeader
+	data []byte
+}
+
+func (f *http2DataFrame) StreamEnded() bool {
+	return f.http2FrameHeader.Flags.Has(http2FlagDataEndStream)
+}
+
+// Data returns the frame's data octets, not including any padding
+// size byte or padding suffix bytes.
+// The caller must not retain the returned memory past the next
+// call to ReadFrame.
+func (f *http2DataFrame) Data() []byte {
+	f.checkValid()
+	return f.data
+}
+
+func http2parseDataFrame(fc *http2frameCache, fh http2FrameHeader, countError func(string), payload []byte) (http2Frame, error) {
+	if fh.StreamID == 0 {
+		// DATA frames MUST be associated with a stream. If a
+		// DATA frame is received whose stream identifier
+		// field is 0x0, the recipient MUST respond with a
+		// connection error (Section 5.4.1) of type
+		// PROTOCOL_ERROR.
+		countError("frame_data_stream_0")
+		return nil, http2connError{http2ErrCodeProtocol, "DATA frame with stream ID 0"}
+	}
+	f := fc.getDataFrame()
+	f.http2FrameHeader = fh
+
+	var padSize byte
+	if fh.Flags.Has(http2FlagDataPadded) {
+		var err error
+		payload, padSize, err = http2readByte(payload)
+		if err != nil {
+			countError("frame_data_pad_byte_short")
+			return nil, err
+		}
+	}
+	if int(padSize) > len(payload) {
+		// If the length of the padding is greater than the
+		// length of the frame payload, the recipient MUST
+		// treat this as a connection error.
+		// Filed: https://github.com/http2/http2-spec/issues/610
+		countError("frame_data_pad_too_big")
+		return nil, http2connError{http2ErrCodeProtocol, "pad size larger than data payload"}
+	}
+	f.data = payload[:len(payload)-int(padSize)]
+	return f, nil
+}
+
+var (
+	http2errStreamID    = errors.New("invalid stream ID")
+	http2errDepStreamID = errors.New("invalid dependent stream ID")
+	http2errPadLength   = errors.New("pad length too large")
+	http2errPadBytes    = errors.New("padding bytes must all be zeros unless AllowIllegalWrites is enabled")
+)
+
+func http2validStreamIDOrZero(streamID uint32) bool {
+	return streamID&(1<<31) == 0
+}
+
+func http2validStreamID(streamID uint32) bool {
+	return streamID != 0 && streamID&(1<<31) == 0
+}
+
+// WriteData writes a DATA frame.
+//
+// It will perform exactly one Write to the underlying Writer.
+// It is the caller's responsibility not to violate the maximum frame size
+// and to not call other Write methods concurrently.
+func (f *http2Framer) WriteData(streamID uint32, endStream bool, data []byte) error {
+	return f.WriteDataPadded(streamID, endStream, data, nil)
+}
+
+// WriteDataPadded writes a DATA frame with optional padding.
+//
+// If pad is nil, the padding bit is not sent.
+// The length of pad must not exceed 255 bytes.
+// The bytes of pad must all be zero, unless f.AllowIllegalWrites is set.
+//
+// It will perform exactly one Write to the underlying Writer.
+// It is the caller's responsibility not to violate the maximum frame size
+// and to not call other Write methods concurrently.
+func (f *http2Framer) WriteDataPadded(streamID uint32, endStream bool, data, pad []byte) error {
+	if !http2validStreamID(streamID) && !f.AllowIllegalWrites {
+		return http2errStreamID
+	}
+	if len(pad) > 0 {
+		if len(pad) > 255 {
+			return http2errPadLength
+		}
+		if !f.AllowIllegalWrites {
+			for _, b := range pad {
+				if b != 0 {
+					// "Padding octets MUST be set to zero when sending."
+					return http2errPadBytes
+				}
+			}
+		}
+	}
+	var flags http2Flags
+	if endStream {
+		flags |= http2FlagDataEndStream
+	}
+	if pad != nil {
+		flags |= http2FlagDataPadded
+	}
+	f.startWrite(http2FrameData, flags, streamID)
+	if pad != nil {
+		f.wbuf = append(f.wbuf, byte(len(pad)))
+	}
+	f.wbuf = append(f.wbuf, data...)
+	f.wbuf = append(f.wbuf, pad...)
+	return f.endWrite()
+}
+
+// A SettingsFrame conveys configuration parameters that affect how
+// endpoints communicate, such as preferences and constraints on peer
+// behavior.
+//
+// See http://http2.github.io/http2-spec/#SETTINGS
+type http2SettingsFrame struct {
+	http2FrameHeader
+	p []byte
+}
+
+func http2parseSettingsFrame(_ *http2frameCache, fh http2FrameHeader, countError func(string), p []byte) (http2Frame, error) {
+	if fh.Flags.Has(http2FlagSettingsAck) && fh.Length > 0 {
+		// When this (ACK 0x1) bit is set, the payload of the
+		// SETTINGS frame MUST be empty. Receipt of a
+		// SETTINGS frame with the ACK flag set and a length
+		// field value other than 0 MUST be treated as a
+		// connection error (Section 5.4.1) of type
+		// FRAME_SIZE_ERROR.
+		countError("frame_settings_ack_with_length")
+		return nil, http2ConnectionError(http2ErrCodeFrameSize)
+	}
+	if fh.StreamID != 0 {
+		// SETTINGS frames always apply to a connection,
+		// never a single stream. The stream identifier for a
+		// SETTINGS frame MUST be zero (0x0).  If an endpoint
+		// receives a SETTINGS frame whose stream identifier
+		// field is anything other than 0x0, the endpoint MUST
+		// respond with a connection error (Section 5.4.1) of
+		// type PROTOCOL_ERROR.
+		countError("frame_settings_has_stream")
+		return nil, http2ConnectionError(http2ErrCodeProtocol)
+	}
+	if len(p)%6 != 0 {
+		countError("frame_settings_mod_6")
+		// Expecting even number of 6 byte settings.
+		return nil, http2ConnectionError(http2ErrCodeFrameSize)
+	}
+	f := &http2SettingsFrame{http2FrameHeader: fh, p: p}
+	if v, ok := f.Value(http2SettingInitialWindowSize); ok && v > (1<<31)-1 {
+		countError("frame_settings_window_size_too_big")
+		// Values above the maximum flow control window size of 2^31 - 1 MUST
+		// be treated as a connection error (Section 5.4.1) of type
+		// FLOW_CONTROL_ERROR.
+		return nil, http2ConnectionError(http2ErrCodeFlowControl)
+	}
+	return f, nil
+}
+
+func (f *http2SettingsFrame) IsAck() bool {
+	return f.http2FrameHeader.Flags.Has(http2FlagSettingsAck)
+}
+
+func (f *http2SettingsFrame) Value(id http2SettingID) (v uint32, ok bool) {
+	f.checkValid()
+	for i := 0; i < f.NumSettings(); i++ {
+		if s := f.Setting(i); s.ID == id {
+			return s.Val, true
+		}
+	}
+	return 0, false
+}
+
+// Setting returns the setting from the frame at the given 0-based index.
+// The index must be >= 0 and less than f.NumSettings().
+func (f *http2SettingsFrame) Setting(i int) http2Setting {
+	buf := f.p
+	return http2Setting{
+		ID:  http2SettingID(binary.BigEndian.Uint16(buf[i*6 : i*6+2])),
+		Val: binary.BigEndian.Uint32(buf[i*6+2 : i*6+6]),
+	}
+}
+
+func (f *http2SettingsFrame) NumSettings() int { return len(f.p) / 6 }
+
+// HasDuplicates reports whether f contains any duplicate setting IDs.
+func (f *http2SettingsFrame) HasDuplicates() bool {
+	num := f.NumSettings()
+	if num == 0 {
+		return false
+	}
+	// If it's small enough (the common case), just do the n^2
+	// thing and avoid a map allocation.
+	if num < 10 {
+		for i := 0; i < num; i++ {
+			idi := f.Setting(i).ID
+			for j := i + 1; j < num; j++ {
+				idj := f.Setting(j).ID
+				if idi == idj {
+					return true
+				}
+			}
+		}
+		return false
+	}
+	seen := map[http2SettingID]bool{}
+	for i := 0; i < num; i++ {
+		id := f.Setting(i).ID
+		if seen[id] {
+			return true
+		}
+		seen[id] = true
+	}
+	return false
+}
+
+// ForeachSetting runs fn for each setting.
+// It stops and returns the first error.
+func (f *http2SettingsFrame) ForeachSetting(fn func(http2Setting) error) error {
+	f.checkValid()
+	for i := 0; i < f.NumSettings(); i++ {
+		if err := fn(f.Setting(i)); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// WriteSettings writes a SETTINGS frame with zero or more settings
+// specified and the ACK bit not set.
+//
+// It will perform exactly one Write to the underlying Writer.
+// It is the caller's responsibility to not call other Write methods concurrently.
+func (f *http2Framer) WriteSettings(settings ...http2Setting) error {
+	f.startWrite(http2FrameSettings, 0, 0)
+	for _, s := range settings {
+		f.writeUint16(uint16(s.ID))
+		f.writeUint32(s.Val)
+	}
+	return f.endWrite()
+}
+
+// WriteSettingsAck writes an empty SETTINGS frame with the ACK bit set.
+//
+// It will perform exactly one Write to the underlying Writer.
+// It is the caller's responsibility to not call other Write methods concurrently.
+func (f *http2Framer) WriteSettingsAck() error {
+	f.startWrite(http2FrameSettings, http2FlagSettingsAck, 0)
+	return f.endWrite()
+}
+
+// A PingFrame is a mechanism for measuring a minimal round trip time
+// from the sender, as well as determining whether an idle connection
+// is still functional.
+// See http://http2.github.io/http2-spec/#rfc.section.6.7
+type http2PingFrame struct {
+	http2FrameHeader
+	Data [8]byte
+}
+
+func (f *http2PingFrame) IsAck() bool { return f.Flags.Has(http2FlagPingAck) }
+
+func http2parsePingFrame(_ *http2frameCache, fh http2FrameHeader, countError func(string), payload []byte) (http2Frame, error) {
+	if len(payload) != 8 {
+		countError("frame_ping_length")
+		return nil, http2ConnectionError(http2ErrCodeFrameSize)
+	}
+	if fh.StreamID != 0 {
+		countError("frame_ping_has_stream")
+		return nil, http2ConnectionError(http2ErrCodeProtocol)
+	}
+	f := &http2PingFrame{http2FrameHeader: fh}
+	copy(f.Data[:], payload)
+	return f, nil
+}
+
+func (f *http2Framer) WritePing(ack bool, data [8]byte) error {
+	var flags http2Flags
+	if ack {
+		flags = http2FlagPingAck
+	}
+	f.startWrite(http2FramePing, flags, 0)
+	f.writeBytes(data[:])
+	return f.endWrite()
+}
+
+// A GoAwayFrame informs the remote peer to stop creating streams on this connection.
+// See http://http2.github.io/http2-spec/#rfc.section.6.8
+type http2GoAwayFrame struct {
+	http2FrameHeader
+	LastStreamID uint32
+	ErrCode      http2ErrCode
+	debugData    []byte
+}
+
+// DebugData returns any debug data in the GOAWAY frame. Its contents
+// are not defined.
+// The caller must not retain the returned memory past the next
+// call to ReadFrame.
+func (f *http2GoAwayFrame) DebugData() []byte {
+	f.checkValid()
+	return f.debugData
+}
+
+func http2parseGoAwayFrame(_ *http2frameCache, fh http2FrameHeader, countError func(string), p []byte) (http2Frame, error) {
+	if fh.StreamID != 0 {
+		countError("frame_goaway_has_stream")
+		return nil, http2ConnectionError(http2ErrCodeProtocol)
+	}
+	if len(p) < 8 {
+		countError("frame_goaway_short")
+		return nil, http2ConnectionError(http2ErrCodeFrameSize)
+	}
+	return &http2GoAwayFrame{
+		http2FrameHeader: fh,
+		LastStreamID:     binary.BigEndian.Uint32(p[:4]) & (1<<31 - 1),
+		ErrCode:          http2ErrCode(binary.BigEndian.Uint32(p[4:8])),
+		debugData:        p[8:],
+	}, nil
+}
+
+func (f *http2Framer) WriteGoAway(maxStreamID uint32, code http2ErrCode, debugData []byte) error {
+	f.startWrite(http2FrameGoAway, 0, 0)
+	f.writeUint32(maxStreamID & (1<<31 - 1))
+	f.writeUint32(uint32(code))
+	f.writeBytes(debugData)
+	return f.endWrite()
+}
+
+// An UnknownFrame is the frame type returned when the frame type is unknown
+// or no specific frame type parser exists.
+type http2UnknownFrame struct {
+	http2FrameHeader
+	p []byte
+}
+
+// Payload returns the frame's payload (after the header).  It is not
+// valid to call this method after a subsequent call to
+// Framer.ReadFrame, nor is it valid to retain the returned slice.
+// The memory is owned by the Framer and is invalidated when the next
+// frame is read.
+func (f *http2UnknownFrame) Payload() []byte {
+	f.checkValid()
+	return f.p
+}
+
+func http2parseUnknownFrame(_ *http2frameCache, fh http2FrameHeader, countError func(string), p []byte) (http2Frame, error) {
+	return &http2UnknownFrame{fh, p}, nil
+}
+
+// A WindowUpdateFrame is used to implement flow control.
+// See http://http2.github.io/http2-spec/#rfc.section.6.9
+type http2WindowUpdateFrame struct {
+	http2FrameHeader
+	Increment uint32 // never read with high bit set
+}
+
+func http2parseWindowUpdateFrame(_ *http2frameCache, fh http2FrameHeader, countError func(string), p []byte) (http2Frame, error) {
+	if len(p) != 4 {
+		countError("frame_windowupdate_bad_len")
+		return nil, http2ConnectionError(http2ErrCodeFrameSize)
+	}
+	inc := binary.BigEndian.Uint32(p[:4]) & 0x7fffffff // mask off high reserved bit
+	if inc == 0 {
+		// A receiver MUST treat the receipt of a
+		// WINDOW_UPDATE frame with an flow control window
+		// increment of 0 as a stream error (Section 5.4.2) of
+		// type PROTOCOL_ERROR; errors on the connection flow
+		// control window MUST be treated as a connection
+		// error (Section 5.4.1).
+		if fh.StreamID == 0 {
+			countError("frame_windowupdate_zero_inc_conn")
+			return nil, http2ConnectionError(http2ErrCodeProtocol)
+		}
+		countError("frame_windowupdate_zero_inc_stream")
+		return nil, http2streamError(fh.StreamID, http2ErrCodeProtocol)
+	}
+	return &http2WindowUpdateFrame{
+		http2FrameHeader: fh,
+		Increment:        inc,
+	}, nil
+}
+
+// WriteWindowUpdate writes a WINDOW_UPDATE frame.
+// The increment value must be between 1 and 2,147,483,647, inclusive.
+// If the Stream ID is zero, the window update applies to the
+// connection as a whole.
+func (f *http2Framer) WriteWindowUpdate(streamID, incr uint32) error {
+	// "The legal range for the increment to the flow control window is 1 to 2^31-1 (2,147,483,647) octets."
+	if (incr < 1 || incr > 2147483647) && !f.AllowIllegalWrites {
+		return errors.New("illegal window increment value")
+	}
+	f.startWrite(http2FrameWindowUpdate, 0, streamID)
+	f.writeUint32(incr)
+	return f.endWrite()
+}
+
+// A HeadersFrame is used to open a stream and additionally carries a
+// header block fragment.
+type http2HeadersFrame struct {
+	http2FrameHeader
+
+	// Priority is set if FlagHeadersPriority is set in the FrameHeader.
+	Priority http2PriorityParam
+
+	headerFragBuf []byte // not owned
+}
+
+func (f *http2HeadersFrame) HeaderBlockFragment() []byte {
+	f.checkValid()
+	return f.headerFragBuf
+}
+
+func (f *http2HeadersFrame) HeadersEnded() bool {
+	return f.http2FrameHeader.Flags.Has(http2FlagHeadersEndHeaders)
+}
+
+func (f *http2HeadersFrame) StreamEnded() bool {
+	return f.http2FrameHeader.Flags.Has(http2FlagHeadersEndStream)
+}
+
+func (f *http2HeadersFrame) HasPriority() bool {
+	return f.http2FrameHeader.Flags.Has(http2FlagHeadersPriority)
+}
+
+func http2parseHeadersFrame(_ *http2frameCache, fh http2FrameHeader, countError func(string), p []byte) (_ http2Frame, err error) {
+	hf := &http2HeadersFrame{
+		http2FrameHeader: fh,
+	}
+	if fh.StreamID == 0 {
+		// HEADERS frames MUST be associated with a stream. If a HEADERS frame
+		// is received whose stream identifier field is 0x0, the recipient MUST
+		// respond with a connection error (Section 5.4.1) of type
+		// PROTOCOL_ERROR.
+		countError("frame_headers_zero_stream")
+		return nil, http2connError{http2ErrCodeProtocol, "HEADERS frame with stream ID 0"}
+	}
+	var padLength uint8
+	if fh.Flags.Has(http2FlagHeadersPadded) {
+		if p, padLength, err = http2readByte(p); err != nil {
+			countError("frame_headers_pad_short")
+			return
+		}
+	}
+	if fh.Flags.Has(http2FlagHeadersPriority) {
+		var v uint32
+		p, v, err = http2readUint32(p)
+		if err != nil {
+			countError("frame_headers_prio_short")
+			return nil, err
+		}
+		hf.Priority.StreamDep = v & 0x7fffffff
+		hf.Priority.Exclusive = (v != hf.Priority.StreamDep) // high bit was set
+		p, hf.Priority.Weight, err = http2readByte(p)
+		if err != nil {
+			countError("frame_headers_prio_weight_short")
+			return nil, err
+		}
+	}
+	if len(p)-int(padLength) < 0 {
+		countError("frame_headers_pad_too_big")
+		return nil, http2streamError(fh.StreamID, http2ErrCodeProtocol)
+	}
+	hf.headerFragBuf = p[:len(p)-int(padLength)]
+	return hf, nil
+}
+
+// HeadersFrameParam are the parameters for writing a HEADERS frame.
+type http2HeadersFrameParam struct {
+	// StreamID is the required Stream ID to initiate.
+	StreamID uint32
+	// BlockFragment is part (or all) of a Header Block.
+	BlockFragment []byte
+
+	// EndStream indicates that the header block is the last that
+	// the endpoint will send for the identified stream. Setting
+	// this flag causes the stream to enter one of "half closed"
+	// states.
+	EndStream bool
+
+	// EndHeaders indicates that this frame contains an entire
+	// header block and is not followed by any
+	// CONTINUATION frames.
+	EndHeaders bool
+
+	// PadLength is the optional number of bytes of zeros to add
+	// to this frame.
+	PadLength uint8
+
+	// Priority, if non-zero, includes stream priority information
+	// in the HEADER frame.
+	Priority http2PriorityParam
+}
+
+// WriteHeaders writes a single HEADERS frame.
+//
+// This is a low-level header writing method. Encoding headers and
+// splitting them into any necessary CONTINUATION frames is handled
+// elsewhere.
+//
+// It will perform exactly one Write to the underlying Writer.
+// It is the caller's responsibility to not call other Write methods concurrently.
+func (f *http2Framer) WriteHeaders(p http2HeadersFrameParam) error {
+	if !http2validStreamID(p.StreamID) && !f.AllowIllegalWrites {
+		return http2errStreamID
+	}
+	var flags http2Flags
+	if p.PadLength != 0 {
+		flags |= http2FlagHeadersPadded
+	}
+	if p.EndStream {
+		flags |= http2FlagHeadersEndStream
+	}
+	if p.EndHeaders {
+		flags |= http2FlagHeadersEndHeaders
+	}
+	if !p.Priority.IsZero() {
+		flags |= http2FlagHeadersPriority
+	}
+	f.startWrite(http2FrameHeaders, flags, p.StreamID)
+	if p.PadLength != 0 {
+		f.writeByte(p.PadLength)
+	}
+	if !p.Priority.IsZero() {
+		v := p.Priority.StreamDep
+		if !http2validStreamIDOrZero(v) && !f.AllowIllegalWrites {
+			return http2errDepStreamID
+		}
+		if p.Priority.Exclusive {
+			v |= 1 << 31
+		}
+		f.writeUint32(v)
+		f.writeByte(p.Priority.Weight)
+	}
+	f.wbuf = append(f.wbuf, p.BlockFragment...)
+	f.wbuf = append(f.wbuf, http2padZeros[:p.PadLength]...)
+	return f.endWrite()
+}
+
+// A PriorityFrame specifies the sender-advised priority of a stream.
+// See http://http2.github.io/http2-spec/#rfc.section.6.3
+type http2PriorityFrame struct {
+	http2FrameHeader
+	http2PriorityParam
+}
+
+// PriorityParam are the stream prioritzation parameters.
+type http2PriorityParam struct {
+	// StreamDep is a 31-bit stream identifier for the
+	// stream that this stream depends on. Zero means no
+	// dependency.
+	StreamDep uint32
+
+	// Exclusive is whether the dependency is exclusive.
+	Exclusive bool
+
+	// Weight is the stream's zero-indexed weight. It should be
+	// set together with StreamDep, or neither should be set. Per
+	// the spec, "Add one to the value to obtain a weight between
+	// 1 and 256."
+	Weight uint8
+}
+
+func (p http2PriorityParam) IsZero() bool {
+	return p == http2PriorityParam{}
+}
+
+func http2parsePriorityFrame(_ *http2frameCache, fh http2FrameHeader, countError func(string), payload []byte) (http2Frame, error) {
+	if fh.StreamID == 0 {
+		countError("frame_priority_zero_stream")
+		return nil, http2connError{http2ErrCodeProtocol, "PRIORITY frame with stream ID 0"}
+	}
+	if len(payload) != 5 {
+		countError("frame_priority_bad_length")
+		return nil, http2connError{http2ErrCodeFrameSize, fmt.Sprintf("PRIORITY frame payload size was %d; want 5", len(payload))}
+	}
+	v := binary.BigEndian.Uint32(payload[:4])
+	streamID := v & 0x7fffffff // mask off high bit
+	return &http2PriorityFrame{
+		http2FrameHeader: fh,
+		http2PriorityParam: http2PriorityParam{
+			Weight:    payload[4],
+			StreamDep: streamID,
+			Exclusive: streamID != v, // was high bit set?
+		},
+	}, nil
+}
+
+// WritePriority writes a PRIORITY frame.
+//
+// It will perform exactly one Write to the underlying Writer.
+// It is the caller's responsibility to not call other Write methods concurrently.
+func (f *http2Framer) WritePriority(streamID uint32, p http2PriorityParam) error {
+	if !http2validStreamID(streamID) && !f.AllowIllegalWrites {
+		return http2errStreamID
+	}
+	if !http2validStreamIDOrZero(p.StreamDep) {
+		return http2errDepStreamID
+	}
+	f.startWrite(http2FramePriority, 0, streamID)
+	v := p.StreamDep
+	if p.Exclusive {
+		v |= 1 << 31
+	}
+	f.writeUint32(v)
+	f.writeByte(p.Weight)
+	return f.endWrite()
+}
+
+// A RSTStreamFrame allows for abnormal termination of a stream.
+// See http://http2.github.io/http2-spec/#rfc.section.6.4
+type http2RSTStreamFrame struct {
+	http2FrameHeader
+	ErrCode http2ErrCode
+}
+
+func http2parseRSTStreamFrame(_ *http2frameCache, fh http2FrameHeader, countError func(string), p []byte) (http2Frame, error) {
+	if len(p) != 4 {
+		countError("frame_rststream_bad_len")
+		return nil, http2ConnectionError(http2ErrCodeFrameSize)
+	}
+	if fh.StreamID == 0 {
+		countError("frame_rststream_zero_stream")
+		return nil, http2ConnectionError(http2ErrCodeProtocol)
+	}
+	return &http2RSTStreamFrame{fh, http2ErrCode(binary.BigEndian.Uint32(p[:4]))}, nil
+}
+
+// WriteRSTStream writes a RST_STREAM frame.
+//
+// It will perform exactly one Write to the underlying Writer.
+// It is the caller's responsibility to not call other Write methods concurrently.
+func (f *http2Framer) WriteRSTStream(streamID uint32, code http2ErrCode) error {
+	if !http2validStreamID(streamID) && !f.AllowIllegalWrites {
+		return http2errStreamID
+	}
+	f.startWrite(http2FrameRSTStream, 0, streamID)
+	f.writeUint32(uint32(code))
+	return f.endWrite()
+}
+
+// A ContinuationFrame is used to continue a sequence of header block fragments.
+// See http://http2.github.io/http2-spec/#rfc.section.6.10
+type http2ContinuationFrame struct {
+	http2FrameHeader
+	headerFragBuf []byte
+}
+
+func http2parseContinuationFrame(_ *http2frameCache, fh http2FrameHeader, countError func(string), p []byte) (http2Frame, error) {
+	if fh.StreamID == 0 {
+		countError("frame_continuation_zero_stream")
+		return nil, http2connError{http2ErrCodeProtocol, "CONTINUATION frame with stream ID 0"}
+	}
+	return &http2ContinuationFrame{fh, p}, nil
+}
+
+func (f *http2ContinuationFrame) HeaderBlockFragment() []byte {
+	f.checkValid()
+	return f.headerFragBuf
+}
+
+func (f *http2ContinuationFrame) HeadersEnded() bool {
+	return f.http2FrameHeader.Flags.Has(http2FlagContinuationEndHeaders)
+}
+
+// WriteContinuation writes a CONTINUATION frame.
+//
+// It will perform exactly one Write to the underlying Writer.
+// It is the caller's responsibility to not call other Write methods concurrently.
+func (f *http2Framer) WriteContinuation(streamID uint32, endHeaders bool, headerBlockFragment []byte) error {
+	if !http2validStreamID(streamID) && !f.AllowIllegalWrites {
+		return http2errStreamID
+	}
+	var flags http2Flags
+	if endHeaders {
+		flags |= http2FlagContinuationEndHeaders
+	}
+	f.startWrite(http2FrameContinuation, flags, streamID)
+	f.wbuf = append(f.wbuf, headerBlockFragment...)
+	return f.endWrite()
+}
+
+// A PushPromiseFrame is used to initiate a server stream.
+// See http://http2.github.io/http2-spec/#rfc.section.6.6
+type http2PushPromiseFrame struct {
+	http2FrameHeader
+	PromiseID     uint32
+	headerFragBuf []byte // not owned
+}
+
+func (f *http2PushPromiseFrame) HeaderBlockFragment() []byte {
+	f.checkValid()
+	return f.headerFragBuf
+}
+
+func (f *http2PushPromiseFrame) HeadersEnded() bool {
+	return f.http2FrameHeader.Flags.Has(http2FlagPushPromiseEndHeaders)
+}
+
+func http2parsePushPromise(_ *http2frameCache, fh http2FrameHeader, countError func(string), p []byte) (_ http2Frame, err error) {
+	pp := &http2PushPromiseFrame{
+		http2FrameHeader: fh,
+	}
+	if pp.StreamID == 0 {
+		// PUSH_PROMISE frames MUST be associated with an existing,
+		// peer-initiated stream. The stream identifier of a
+		// PUSH_PROMISE frame indicates the stream it is associated
+		// with. If the stream identifier field specifies the value
+		// 0x0, a recipient MUST respond with a connection error
+		// (Section 5.4.1) of type PROTOCOL_ERROR.
+		countError("frame_pushpromise_zero_stream")
+		return nil, http2ConnectionError(http2ErrCodeProtocol)
+	}
+	// The PUSH_PROMISE frame includes optional padding.
+	// Padding fields and flags are identical to those defined for DATA frames
+	var padLength uint8
+	if fh.Flags.Has(http2FlagPushPromisePadded) {
+		if p, padLength, err = http2readByte(p); err != nil {
+			countError("frame_pushpromise_pad_short")
+			return
+		}
+	}
+
+	p, pp.PromiseID, err = http2readUint32(p)
+	if err != nil {
+		countError("frame_pushpromise_promiseid_short")
+		return
+	}
+	pp.PromiseID = pp.PromiseID & (1<<31 - 1)
+
+	if int(padLength) > len(p) {
+		// like the DATA frame, error out if padding is longer than the body.
+		countError("frame_pushpromise_pad_too_big")
+		return nil, http2ConnectionError(http2ErrCodeProtocol)
+	}
+	pp.headerFragBuf = p[:len(p)-int(padLength)]
+	return pp, nil
+}
+
+// PushPromiseParam are the parameters for writing a PUSH_PROMISE frame.
+type http2PushPromiseParam struct {
+	// StreamID is the required Stream ID to initiate.
+	StreamID uint32
+
+	// PromiseID is the required Stream ID which this
+	// Push Promises
+	PromiseID uint32
+
+	// BlockFragment is part (or all) of a Header Block.
+	BlockFragment []byte
+
+	// EndHeaders indicates that this frame contains an entire
+	// header block and is not followed by any
+	// CONTINUATION frames.
+	EndHeaders bool
+
+	// PadLength is the optional number of bytes of zeros to add
+	// to this frame.
+	PadLength uint8
+}
+
+// WritePushPromise writes a single PushPromise Frame.
+//
+// As with Header Frames, This is the low level call for writing
+// individual frames. Continuation frames are handled elsewhere.
+//
+// It will perform exactly one Write to the underlying Writer.
+// It is the caller's responsibility to not call other Write methods concurrently.
+func (f *http2Framer) WritePushPromise(p http2PushPromiseParam) error {
+	if !http2validStreamID(p.StreamID) && !f.AllowIllegalWrites {
+		return http2errStreamID
+	}
+	var flags http2Flags
+	if p.PadLength != 0 {
+		flags |= http2FlagPushPromisePadded
+	}
+	if p.EndHeaders {
+		flags |= http2FlagPushPromiseEndHeaders
+	}
+	f.startWrite(http2FramePushPromise, flags, p.StreamID)
+	if p.PadLength != 0 {
+		f.writeByte(p.PadLength)
+	}
+	if !http2validStreamID(p.PromiseID) && !f.AllowIllegalWrites {
+		return http2errStreamID
+	}
+	f.writeUint32(p.PromiseID)
+	f.wbuf = append(f.wbuf, p.BlockFragment...)
+	f.wbuf = append(f.wbuf, http2padZeros[:p.PadLength]...)
+	return f.endWrite()
+}
+
+// WriteRawFrame writes a raw frame. This can be used to write
+// extension frames unknown to this package.
+func (f *http2Framer) WriteRawFrame(t http2FrameType, flags http2Flags, streamID uint32, payload []byte) error {
+	f.startWrite(t, flags, streamID)
+	f.writeBytes(payload)
+	return f.endWrite()
+}
+
+func http2readByte(p []byte) (remain []byte, b byte, err error) {
+	if len(p) == 0 {
+		return nil, 0, io.ErrUnexpectedEOF
+	}
+	return p[1:], p[0], nil
+}
+
+func http2readUint32(p []byte) (remain []byte, v uint32, err error) {
+	if len(p) < 4 {
+		return nil, 0, io.ErrUnexpectedEOF
+	}
+	return p[4:], binary.BigEndian.Uint32(p[:4]), nil
+}
+
+type http2streamEnder interface {
+	StreamEnded() bool
+}
+
+type http2headersEnder interface {
+	HeadersEnded() bool
+}
+
+type http2headersOrContinuation interface {
+	http2headersEnder
+	HeaderBlockFragment() []byte
+}
+
+// A MetaHeadersFrame is the representation of one HEADERS frame and
+// zero or more contiguous CONTINUATION frames and the decoding of
+// their HPACK-encoded contents.
+//
+// This type of frame does not appear on the wire and is only returned
+// by the Framer when Framer.ReadMetaHeaders is set.
+type http2MetaHeadersFrame struct {
+	*http2HeadersFrame
+
+	// Fields are the fields contained in the HEADERS and
+	// CONTINUATION frames. The underlying slice is owned by the
+	// Framer and must not be retained after the next call to
+	// ReadFrame.
+	//
+	// Fields are guaranteed to be in the correct http2 order and
+	// not have unknown pseudo header fields or invalid header
+	// field names or values. Required pseudo header fields may be
+	// missing, however. Use the MetaHeadersFrame.Pseudo accessor
+	// method access pseudo headers.
+	Fields []hpack.HeaderField
+
+	// Truncated is whether the max header list size limit was hit
+	// and Fields is incomplete. The hpack decoder state is still
+	// valid, however.
+	Truncated bool
+}
+
+// PseudoValue returns the given pseudo header field's value.
+// The provided pseudo field should not contain the leading colon.
+func (mh *http2MetaHeadersFrame) PseudoValue(pseudo string) string {
+	for _, hf := range mh.Fields {
+		if !hf.IsPseudo() {
+			return ""
+		}
+		if hf.Name[1:] == pseudo {
+			return hf.Value
+		}
+	}
+	return ""
+}
+
+// RegularFields returns the regular (non-pseudo) header fields of mh.
+// The caller does not own the returned slice.
+func (mh *http2MetaHeadersFrame) RegularFields() []hpack.HeaderField {
+	for i, hf := range mh.Fields {
+		if !hf.IsPseudo() {
+			return mh.Fields[i:]
+		}
+	}
+	return nil
+}
+
+// PseudoFields returns the pseudo header fields of mh.
+// The caller does not own the returned slice.
+func (mh *http2MetaHeadersFrame) PseudoFields() []hpack.HeaderField {
+	for i, hf := range mh.Fields {
+		if !hf.IsPseudo() {
+			return mh.Fields[:i]
+		}
+	}
+	return mh.Fields
+}
+
+func (mh *http2MetaHeadersFrame) checkPseudos() error {
+	var isRequest, isResponse bool
+	pf := mh.PseudoFields()
+	for i, hf := range pf {
+		switch hf.Name {
+		case ":method", ":path", ":scheme", ":authority":
+			isRequest = true
+		case ":status":
+			isResponse = true
+		default:
+			return http2pseudoHeaderError(hf.Name)
+		}
+		// Check for duplicates.
+		// This would be a bad algorithm, but N is 4.
+		// And this doesn't allocate.
+		for _, hf2 := range pf[:i] {
+			if hf.Name == hf2.Name {
+				return http2duplicatePseudoHeaderError(hf.Name)
+			}
+		}
+	}
+	if isRequest && isResponse {
+		return http2errMixPseudoHeaderTypes
+	}
+	return nil
+}
+
+func (fr *http2Framer) maxHeaderStringLen() int {
+	v := fr.maxHeaderListSize()
+	if uint32(int(v)) == v {
+		return int(v)
+	}
+	// They had a crazy big number for MaxHeaderBytes anyway,
+	// so give them unlimited header lengths:
+	return 0
+}
+
+// readMetaFrame returns 0 or more CONTINUATION frames from fr and
+// merge them into the provided hf and returns a MetaHeadersFrame
+// with the decoded hpack values.
+func (fr *http2Framer) readMetaFrame(hf *http2HeadersFrame) (*http2MetaHeadersFrame, error) {
+	if fr.AllowIllegalReads {
+		return nil, errors.New("illegal use of AllowIllegalReads with ReadMetaHeaders")
+	}
+	mh := &http2MetaHeadersFrame{
+		http2HeadersFrame: hf,
+	}
+	var remainSize = fr.maxHeaderListSize()
+	var sawRegular bool
+
+	var invalid error // pseudo header field errors
+	hdec := fr.ReadMetaHeaders
+	hdec.SetEmitEnabled(true)
+	hdec.SetMaxStringLength(fr.maxHeaderStringLen())
+	hdec.SetEmitFunc(func(hf hpack.HeaderField) {
+		if http2VerboseLogs && fr.logReads {
+			fr.debugReadLoggerf("http2: decoded hpack field %+v", hf)
+		}
+		if !httpguts.ValidHeaderFieldValue(hf.Value) {
+			// Don't include the value in the error, because it may be sensitive.
+			invalid = http2headerFieldValueError(hf.Name)
+		}
+		isPseudo := strings.HasPrefix(hf.Name, ":")
+		if isPseudo {
+			if sawRegular {
+				invalid = http2errPseudoAfterRegular
+			}
+		} else {
+			sawRegular = true
+			if !http2validWireHeaderFieldName(hf.Name) {
+				invalid = http2headerFieldNameError(hf.Name)
+			}
+		}
+
+		if invalid != nil {
+			hdec.SetEmitEnabled(false)
+			return
+		}
+
+		size := hf.Size()
+		if size > remainSize {
+			hdec.SetEmitEnabled(false)
+			mh.Truncated = true
+			return
+		}
+		remainSize -= size
+
+		mh.Fields = append(mh.Fields, hf)
+	})
+	// Lose reference to MetaHeadersFrame:
+	defer hdec.SetEmitFunc(func(hf hpack.HeaderField) {})
+
+	var hc http2headersOrContinuation = hf
+	for {
+		frag := hc.HeaderBlockFragment()
+		if _, err := hdec.Write(frag); err != nil {
+			return nil, http2ConnectionError(http2ErrCodeCompression)
+		}
+
+		if hc.HeadersEnded() {
+			break
+		}
+		if f, err := fr.ReadFrame(); err != nil {
+			return nil, err
+		} else {
+			hc = f.(*http2ContinuationFrame) // guaranteed by checkFrameOrder
+		}
+	}
+
+	mh.http2HeadersFrame.headerFragBuf = nil
+	mh.http2HeadersFrame.invalidate()
+
+	if err := hdec.Close(); err != nil {
+		return nil, http2ConnectionError(http2ErrCodeCompression)
+	}
+	if invalid != nil {
+		fr.errDetail = invalid
+		if http2VerboseLogs {
+			log.Printf("http2: invalid header: %v", invalid)
+		}
+		return nil, http2StreamError{mh.StreamID, http2ErrCodeProtocol, invalid}
+	}
+	if err := mh.checkPseudos(); err != nil {
+		fr.errDetail = err
+		if http2VerboseLogs {
+			log.Printf("http2: invalid pseudo headers: %v", err)
+		}
+		return nil, http2StreamError{mh.StreamID, http2ErrCodeProtocol, err}
+	}
+	return mh, nil
+}
+
+func http2summarizeFrame(f http2Frame) string {
+	var buf bytes.Buffer
+	f.Header().writeDebug(&buf)
+	switch f := f.(type) {
+	case *http2SettingsFrame:
+		n := 0
+		f.ForeachSetting(func(s http2Setting) error {
+			n++
+			if n == 1 {
+				buf.WriteString(", settings:")
+			}
+			fmt.Fprintf(&buf, " %v=%v,", s.ID, s.Val)
+			return nil
+		})
+		if n > 0 {
+			buf.Truncate(buf.Len() - 1) // remove trailing comma
+		}
+	case *http2DataFrame:
+		data := f.Data()
+		const max = 256
+		if len(data) > max {
+			data = data[:max]
+		}
+		fmt.Fprintf(&buf, " data=%q", data)
+		if len(f.Data()) > max {
+			fmt.Fprintf(&buf, " (%d bytes omitted)", len(f.Data())-max)
+		}
+	case *http2WindowUpdateFrame:
+		if f.StreamID == 0 {
+			buf.WriteString(" (conn)")
+		}
+		fmt.Fprintf(&buf, " incr=%v", f.Increment)
+	case *http2PingFrame:
+		fmt.Fprintf(&buf, " ping=%q", f.Data[:])
+	case *http2GoAwayFrame:
+		fmt.Fprintf(&buf, " LastStreamID=%v ErrCode=%v Debug=%q",
+			f.LastStreamID, f.ErrCode, f.debugData)
+	case *http2RSTStreamFrame:
+		fmt.Fprintf(&buf, " ErrCode=%v", f.ErrCode)
+	}
+	return buf.String()
+}
+
+func http2traceHasWroteHeaderField(trace *httptrace.ClientTrace) bool {
+	return trace != nil && trace.WroteHeaderField != nil
+}
+
+func http2traceWroteHeaderField(trace *httptrace.ClientTrace, k, v string) {
+	if trace != nil && trace.WroteHeaderField != nil {
+		trace.WroteHeaderField(k, []string{v})
+	}
+}
+
+func http2traceGot1xxResponseFunc(trace *httptrace.ClientTrace) func(int, textproto.MIMEHeader) error {
+	if trace != nil {
+		return trace.Got1xxResponse
+	}
+	return nil
+}
+
+// dialTLSWithContext uses tls.Dialer, added in Go 1.15, to open a TLS
+// connection.
+func (t *http2Transport) dialTLSWithContext(ctx context.Context, network, addr string, cfg *tls.Config) (*tls.Conn, error) {
+	dialer := &tls.Dialer{
+		Config: cfg,
+	}
+	cn, err := dialer.DialContext(ctx, network, addr)
+	if err != nil {
+		return nil, err
+	}
+	tlsCn := cn.(*tls.Conn) // DialContext comment promises this will always succeed
+	return tlsCn, nil
+}
+
+func http2tlsUnderlyingConn(tc *tls.Conn) net.Conn {
+	return tc.NetConn()
+}
+
+var http2DebugGoroutines = os.Getenv("DEBUG_HTTP2_GOROUTINES") == "1"
+
+type http2goroutineLock uint64
+
+func http2newGoroutineLock() http2goroutineLock {
+	if !http2DebugGoroutines {
+		return 0
+	}
+	return http2goroutineLock(http2curGoroutineID())
+}
+
+func (g http2goroutineLock) check() {
+	if !http2DebugGoroutines {
+		return
+	}
+	if http2curGoroutineID() != uint64(g) {
+		panic("running on the wrong goroutine")
+	}
+}
+
+func (g http2goroutineLock) checkNotOn() {
+	if !http2DebugGoroutines {
+		return
+	}
+	if http2curGoroutineID() == uint64(g) {
+		panic("running on the wrong goroutine")
+	}
+}
+
+var http2goroutineSpace = []byte("goroutine ")
+
+func http2curGoroutineID() uint64 {
+	bp := http2littleBuf.Get().(*[]byte)
+	defer http2littleBuf.Put(bp)
+	b := *bp
+	b = b[:runtime.Stack(b, false)]
+	// Parse the 4707 out of "goroutine 4707 ["
+	b = bytes.TrimPrefix(b, http2goroutineSpace)
+	i := bytes.IndexByte(b, ' ')
+	if i < 0 {
+		panic(fmt.Sprintf("No space found in %q", b))
+	}
+	b = b[:i]
+	n, err := http2parseUintBytes(b, 10, 64)
+	if err != nil {
+		panic(fmt.Sprintf("Failed to parse goroutine ID out of %q: %v", b, err))
+	}
+	return n
+}
+
+var http2littleBuf = sync.Pool{
+	New: func() interface{} {
+		buf := make([]byte, 64)
+		return &buf
+	},
+}
+
+// parseUintBytes is like strconv.ParseUint, but using a []byte.
+func http2parseUintBytes(s []byte, base int, bitSize int) (n uint64, err error) {
+	var cutoff, maxVal uint64
+
+	if bitSize == 0 {
+		bitSize = int(strconv.IntSize)
+	}
+
+	s0 := s
+	switch {
+	case len(s) < 1:
+		err = strconv.ErrSyntax
+		goto Error
+
+	case 2 <= base && base <= 36:
+		// valid base; nothing to do
+
+	case base == 0:
+		// Look for octal, hex prefix.
+		switch {
+		case s[0] == '0' && len(s) > 1 && (s[1] == 'x' || s[1] == 'X'):
+			base = 16
+			s = s[2:]
+			if len(s) < 1 {
+				err = strconv.ErrSyntax
+				goto Error
+			}
+		case s[0] == '0':
+			base = 8
+		default:
+			base = 10
+		}
+
+	default:
+		err = errors.New("invalid base " + strconv.Itoa(base))
+		goto Error
+	}
+
+	n = 0
+	cutoff = http2cutoff64(base)
+	maxVal = 1<<uint(bitSize) - 1
+
+	for i := 0; i < len(s); i++ {
+		var v byte
+		d := s[i]
+		switch {
+		case '0' <= d && d <= '9':
+			v = d - '0'
+		case 'a' <= d && d <= 'z':
+			v = d - 'a' + 10
+		case 'A' <= d && d <= 'Z':
+			v = d - 'A' + 10
+		default:
+			n = 0
+			err = strconv.ErrSyntax
+			goto Error
+		}
+		if int(v) >= base {
+			n = 0
+			err = strconv.ErrSyntax
+			goto Error
+		}
+
+		if n >= cutoff {
+			// n*base overflows
+			n = 1<<64 - 1
+			err = strconv.ErrRange
+			goto Error
+		}
+		n *= uint64(base)
+
+		n1 := n + uint64(v)
+		if n1 < n || n1 > maxVal {
+			// n+v overflows
+			n = 1<<64 - 1
+			err = strconv.ErrRange
+			goto Error
+		}
+		n = n1
+	}
+
+	return n, nil
+
+Error:
+	return n, &strconv.NumError{Func: "ParseUint", Num: string(s0), Err: err}
+}
+
+// Return the first number n such that n*base >= 1<<64.
+func http2cutoff64(base int) uint64 {
+	if base < 2 {
+		return 0
+	}
+	return (1<<64-1)/uint64(base) + 1
+}
+
+var (
+	http2commonBuildOnce   sync.Once
+	http2commonLowerHeader map[string]string // Go-Canonical-Case -> lower-case
+	http2commonCanonHeader map[string]string // lower-case -> Go-Canonical-Case
+)
+
+func http2buildCommonHeaderMapsOnce() {
+	http2commonBuildOnce.Do(http2buildCommonHeaderMaps)
+}
+
+func http2buildCommonHeaderMaps() {
+	common := []string{
+		"accept",
+		"accept-charset",
+		"accept-encoding",
+		"accept-language",
+		"accept-ranges",
+		"age",
+		"access-control-allow-origin",
+		"allow",
+		"authorization",
+		"cache-control",
+		"content-disposition",
+		"content-encoding",
+		"content-language",
+		"content-length",
+		"content-location",
+		"content-range",
+		"content-type",
+		"cookie",
+		"date",
+		"etag",
+		"expect",
+		"expires",
+		"from",
+		"host",
+		"if-match",
+		"if-modified-since",
+		"if-none-match",
+		"if-unmodified-since",
+		"last-modified",
+		"link",
+		"location",
+		"max-forwards",
+		"proxy-authenticate",
+		"proxy-authorization",
+		"range",
+		"referer",
+		"refresh",
+		"retry-after",
+		"server",
+		"set-cookie",
+		"strict-transport-security",
+		"trailer",
+		"transfer-encoding",
+		"user-agent",
+		"vary",
+		"via",
+		"www-authenticate",
+	}
+	http2commonLowerHeader = make(map[string]string, len(common))
+	http2commonCanonHeader = make(map[string]string, len(common))
+	for _, v := range common {
+		chk := CanonicalHeaderKey(v)
+		http2commonLowerHeader[chk] = v
+		http2commonCanonHeader[v] = chk
+	}
+}
+
+func http2lowerHeader(v string) (lower string, ascii bool) {
+	http2buildCommonHeaderMapsOnce()
+	if s, ok := http2commonLowerHeader[v]; ok {
+		return s, true
+	}
+	return http2asciiToLower(v)
+}
+
+var (
+	http2VerboseLogs    bool
+	http2logFrameWrites bool
+	http2logFrameReads  bool
+	http2inTests        bool
+)
+
+func init() {
+	e := os.Getenv("GODEBUG")
+	if strings.Contains(e, "http2debug=1") {
+		http2VerboseLogs = true
+	}
+	if strings.Contains(e, "http2debug=2") {
+		http2VerboseLogs = true
+		http2logFrameWrites = true
+		http2logFrameReads = true
+	}
+}
+
+const (
+	// ClientPreface is the string that must be sent by new
+	// connections from clients.
+	http2ClientPreface = "PRI * HTTP/2.0\r\n\r\nSM\r\n\r\n"
+
+	// SETTINGS_MAX_FRAME_SIZE default
+	// http://http2.github.io/http2-spec/#rfc.section.6.5.2
+	http2initialMaxFrameSize = 16384
+
+	// NextProtoTLS is the NPN/ALPN protocol negotiated during
+	// HTTP/2's TLS setup.
+	http2NextProtoTLS = "h2"
+
+	// http://http2.github.io/http2-spec/#SettingValues
+	http2initialHeaderTableSize = 4096
+
+	http2initialWindowSize = 65535 // 6.9.2 Initial Flow Control Window Size
+
+	http2defaultMaxReadFrameSize = 1 << 20
+)
+
+var (
+	http2clientPreface = []byte(http2ClientPreface)
+)
+
+type http2streamState int
+
+// HTTP/2 stream states.
+//
+// See http://tools.ietf.org/html/rfc7540#section-5.1.
+//
+// For simplicity, the server code merges "reserved (local)" into
+// "half-closed (remote)". This is one less state transition to track.
+// The only downside is that we send PUSH_PROMISEs slightly less
+// liberally than allowable. More discussion here:
+// https://lists.w3.org/Archives/Public/ietf-http-wg/2016JulSep/0599.html
+//
+// "reserved (remote)" is omitted since the client code does not
+// support server push.
+const (
+	http2stateIdle http2streamState = iota
+	http2stateOpen
+	http2stateHalfClosedLocal
+	http2stateHalfClosedRemote
+	http2stateClosed
+)
+
+var http2stateName = [...]string{
+	http2stateIdle:             "Idle",
+	http2stateOpen:             "Open",
+	http2stateHalfClosedLocal:  "HalfClosedLocal",
+	http2stateHalfClosedRemote: "HalfClosedRemote",
+	http2stateClosed:           "Closed",
+}
+
+func (st http2streamState) String() string {
+	return http2stateName[st]
+}
+
+// Setting is a setting parameter: which setting it is, and its value.
+type http2Setting struct {
+	// ID is which setting is being set.
+	// See http://http2.github.io/http2-spec/#SettingValues
+	ID http2SettingID
+
+	// Val is the value.
+	Val uint32
+}
+
+func (s http2Setting) String() string {
+	return fmt.Sprintf("[%v = %d]", s.ID, s.Val)
+}
+
+// Valid reports whether the setting is valid.
+func (s http2Setting) Valid() error {
+	// Limits and error codes from 6.5.2 Defined SETTINGS Parameters
+	switch s.ID {
+	case http2SettingEnablePush:
+		if s.Val != 1 && s.Val != 0 {
+			return http2ConnectionError(http2ErrCodeProtocol)
+		}
+	case http2SettingInitialWindowSize:
+		if s.Val > 1<<31-1 {
+			return http2ConnectionError(http2ErrCodeFlowControl)
+		}
+	case http2SettingMaxFrameSize:
+		if s.Val < 16384 || s.Val > 1<<24-1 {
+			return http2ConnectionError(http2ErrCodeProtocol)
+		}
+	}
+	return nil
+}
+
+// A SettingID is an HTTP/2 setting as defined in
+// http://http2.github.io/http2-spec/#iana-settings
+type http2SettingID uint16
+
+const (
+	http2SettingHeaderTableSize      http2SettingID = 0x1
+	http2SettingEnablePush           http2SettingID = 0x2
+	http2SettingMaxConcurrentStreams http2SettingID = 0x3
+	http2SettingInitialWindowSize    http2SettingID = 0x4
+	http2SettingMaxFrameSize         http2SettingID = 0x5
+	http2SettingMaxHeaderListSize    http2SettingID = 0x6
+)
+
+var http2settingName = map[http2SettingID]string{
+	http2SettingHeaderTableSize:      "HEADER_TABLE_SIZE",
+	http2SettingEnablePush:           "ENABLE_PUSH",
+	http2SettingMaxConcurrentStreams: "MAX_CONCURRENT_STREAMS",
+	http2SettingInitialWindowSize:    "INITIAL_WINDOW_SIZE",
+	http2SettingMaxFrameSize:         "MAX_FRAME_SIZE",
+	http2SettingMaxHeaderListSize:    "MAX_HEADER_LIST_SIZE",
+}
+
+func (s http2SettingID) String() string {
+	if v, ok := http2settingName[s]; ok {
+		return v
+	}
+	return fmt.Sprintf("UNKNOWN_SETTING_%d", uint16(s))
+}
+
+// validWireHeaderFieldName reports whether v is a valid header field
+// name (key). See httpguts.ValidHeaderName for the base rules.
+//
+// Further, http2 says:
+//
+//	"Just as in HTTP/1.x, header field names are strings of ASCII
+//	characters that are compared in a case-insensitive
+//	fashion. However, header field names MUST be converted to
+//	lowercase prior to their encoding in HTTP/2. "
+func http2validWireHeaderFieldName(v string) bool {
+	if len(v) == 0 {
+		return false
+	}
+	for _, r := range v {
+		if !httpguts.IsTokenRune(r) {
+			return false
+		}
+		if 'A' <= r && r <= 'Z' {
+			return false
+		}
+	}
+	return true
+}
+
+func http2httpCodeString(code int) string {
+	switch code {
+	case 200:
+		return "200"
+	case 404:
+		return "404"
+	}
+	return strconv.Itoa(code)
+}
+
+// from pkg io
+type http2stringWriter interface {
+	WriteString(s string) (n int, err error)
+}
+
+// A gate lets two goroutines coordinate their activities.
+type http2gate chan struct{}
+
+func (g http2gate) Done() { g <- struct{}{} }
+
+func (g http2gate) Wait() { <-g }
+
+// A closeWaiter is like a sync.WaitGroup but only goes 1 to 0 (open to closed).
+type http2closeWaiter chan struct{}
+
+// Init makes a closeWaiter usable.
+// It exists because so a closeWaiter value can be placed inside a
+// larger struct and have the Mutex and Cond's memory in the same
+// allocation.
+func (cw *http2closeWaiter) Init() {
+	*cw = make(chan struct{})
+}
+
+// Close marks the closeWaiter as closed and unblocks any waiters.
+func (cw http2closeWaiter) Close() {
+	close(cw)
+}
+
+// Wait waits for the closeWaiter to become closed.
+func (cw http2closeWaiter) Wait() {
+	<-cw
+}
+
+// bufferedWriter is a buffered writer that writes to w.
+// Its buffered writer is lazily allocated as needed, to minimize
+// idle memory usage with many connections.
+type http2bufferedWriter struct {
+	_  http2incomparable
+	w  io.Writer     // immutable
+	bw *bufio.Writer // non-nil when data is buffered
+}
+
+func http2newBufferedWriter(w io.Writer) *http2bufferedWriter {
+	return &http2bufferedWriter{w: w}
+}
+
+// bufWriterPoolBufferSize is the size of bufio.Writer's
+// buffers created using bufWriterPool.
+//
+// TODO: pick a less arbitrary value? this is a bit under
+// (3 x typical 1500 byte MTU) at least. Other than that,
+// not much thought went into it.
+const http2bufWriterPoolBufferSize = 4 << 10
+
+var http2bufWriterPool = sync.Pool{
+	New: func() interface{} {
+		return bufio.NewWriterSize(nil, http2bufWriterPoolBufferSize)
+	},
+}
+
+func (w *http2bufferedWriter) Available() int {
+	if w.bw == nil {
+		return http2bufWriterPoolBufferSize
+	}
+	return w.bw.Available()
+}
+
+func (w *http2bufferedWriter) Write(p []byte) (n int, err error) {
+	if w.bw == nil {
+		bw := http2bufWriterPool.Get().(*bufio.Writer)
+		bw.Reset(w.w)
+		w.bw = bw
+	}
+	return w.bw.Write(p)
+}
+
+func (w *http2bufferedWriter) Flush() error {
+	bw := w.bw
+	if bw == nil {
+		return nil
+	}
+	err := bw.Flush()
+	bw.Reset(nil)
+	http2bufWriterPool.Put(bw)
+	w.bw = nil
+	return err
+}
+
+func http2mustUint31(v int32) uint32 {
+	if v < 0 || v > 2147483647 {
+		panic("out of range")
+	}
+	return uint32(v)
+}
+
+// bodyAllowedForStatus reports whether a given response status code
+// permits a body. See RFC 7230, section 3.3.
+func http2bodyAllowedForStatus(status int) bool {
+	switch {
+	case status >= 100 && status <= 199:
+		return false
+	case status == 204:
+		return false
+	case status == 304:
+		return false
+	}
+	return true
+}
+
+type http2httpError struct {
+	_       http2incomparable
+	msg     string
+	timeout bool
+}
+
+func (e *http2httpError) Error() string { return e.msg }
+
+func (e *http2httpError) Timeout() bool { return e.timeout }
+
+func (e *http2httpError) Temporary() bool { return true }
+
+var http2errTimeout error = &http2httpError{msg: "http2: timeout awaiting response headers", timeout: true}
+
+type http2connectionStater interface {
+	ConnectionState() tls.ConnectionState
+}
+
+var http2sorterPool = sync.Pool{New: func() interface{} { return new(http2sorter) }}
+
+type http2sorter struct {
+	v []string // owned by sorter
+}
+
+func (s *http2sorter) Len() int { return len(s.v) }
+
+func (s *http2sorter) Swap(i, j int) { s.v[i], s.v[j] = s.v[j], s.v[i] }
+
+func (s *http2sorter) Less(i, j int) bool { return s.v[i] < s.v[j] }
+
+// Keys returns the sorted keys of h.
+//
+// The returned slice is only valid until s used again or returned to
+// its pool.
+func (s *http2sorter) Keys(h Header) []string {
+	keys := s.v[:0]
+	for k := range h {
+		keys = append(keys, k)
+	}
+	s.v = keys
+	sort.Sort(s)
+	return keys
+}
+
+func (s *http2sorter) SortStrings(ss []string) {
+	// Our sorter works on s.v, which sorter owns, so
+	// stash it away while we sort the user's buffer.
+	save := s.v
+	s.v = ss
+	sort.Sort(s)
+	s.v = save
+}
+
+// validPseudoPath reports whether v is a valid :path pseudo-header
+// value. It must be either:
+//
+//   - a non-empty string starting with '/'
+//   - the string '*', for OPTIONS requests.
+//
+// For now this is only used a quick check for deciding when to clean
+// up Opaque URLs before sending requests from the Transport.
+// See golang.org/issue/16847
+//
+// We used to enforce that the path also didn't start with "//", but
+// Google's GFE accepts such paths and Chrome sends them, so ignore
+// that part of the spec. See golang.org/issue/19103.
+func http2validPseudoPath(v string) bool {
+	return (len(v) > 0 && v[0] == '/') || v == "*"
+}
+
+// incomparable is a zero-width, non-comparable type. Adding it to a struct
+// makes that struct also non-comparable, and generally doesn't add
+// any size (as long as it's first).
+type http2incomparable [0]func()
+
+// pipe is a goroutine-safe io.Reader/io.Writer pair. It's like
+// io.Pipe except there are no PipeReader/PipeWriter halves, and the
+// underlying buffer is an interface. (io.Pipe is always unbuffered)
+type http2pipe struct {
+	mu       sync.Mutex
+	c        sync.Cond       // c.L lazily initialized to &p.mu
+	b        http2pipeBuffer // nil when done reading
+	unread   int             // bytes unread when done
+	err      error           // read error once empty. non-nil means closed.
+	breakErr error           // immediate read error (caller doesn't see rest of b)
+	donec    chan struct{}   // closed on error
+	readFn   func()          // optional code to run in Read before error
+}
+
+type http2pipeBuffer interface {
+	Len() int
+	io.Writer
+	io.Reader
+}
+
+// setBuffer initializes the pipe buffer.
+// It has no effect if the pipe is already closed.
+func (p *http2pipe) setBuffer(b http2pipeBuffer) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	if p.err != nil || p.breakErr != nil {
+		return
+	}
+	p.b = b
+}
+
+func (p *http2pipe) Len() int {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	if p.b == nil {
+		return p.unread
+	}
+	return p.b.Len()
+}
+
+// Read waits until data is available and copies bytes
+// from the buffer into p.
+func (p *http2pipe) Read(d []byte) (n int, err error) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	if p.c.L == nil {
+		p.c.L = &p.mu
+	}
+	for {
+		if p.breakErr != nil {
+			return 0, p.breakErr
+		}
+		if p.b != nil && p.b.Len() > 0 {
+			return p.b.Read(d)
+		}
+		if p.err != nil {
+			if p.readFn != nil {
+				p.readFn()     // e.g. copy trailers
+				p.readFn = nil // not sticky like p.err
+			}
+			p.b = nil
+			return 0, p.err
+		}
+		p.c.Wait()
+	}
+}
+
+var http2errClosedPipeWrite = errors.New("write on closed buffer")
+
+// Write copies bytes from p into the buffer and wakes a reader.
+// It is an error to write more data than the buffer can hold.
+func (p *http2pipe) Write(d []byte) (n int, err error) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	if p.c.L == nil {
+		p.c.L = &p.mu
+	}
+	defer p.c.Signal()
+	if p.err != nil {
+		return 0, http2errClosedPipeWrite
+	}
+	if p.breakErr != nil {
+		p.unread += len(d)
+		return len(d), nil // discard when there is no reader
+	}
+	return p.b.Write(d)
+}
+
+// CloseWithError causes the next Read (waking up a current blocked
+// Read if needed) to return the provided err after all data has been
+// read.
+//
+// The error must be non-nil.
+func (p *http2pipe) CloseWithError(err error) { p.closeWithError(&p.err, err, nil) }
+
+// BreakWithError causes the next Read (waking up a current blocked
+// Read if needed) to return the provided err immediately, without
+// waiting for unread data.
+func (p *http2pipe) BreakWithError(err error) { p.closeWithError(&p.breakErr, err, nil) }
+
+// closeWithErrorAndCode is like CloseWithError but also sets some code to run
+// in the caller's goroutine before returning the error.
+func (p *http2pipe) closeWithErrorAndCode(err error, fn func()) { p.closeWithError(&p.err, err, fn) }
+
+func (p *http2pipe) closeWithError(dst *error, err error, fn func()) {
+	if err == nil {
+		panic("err must be non-nil")
+	}
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	if p.c.L == nil {
+		p.c.L = &p.mu
+	}
+	defer p.c.Signal()
+	if *dst != nil {
+		// Already been done.
+		return
+	}
+	p.readFn = fn
+	if dst == &p.breakErr {
+		if p.b != nil {
+			p.unread += p.b.Len()
+		}
+		p.b = nil
+	}
+	*dst = err
+	p.closeDoneLocked()
+}
+
+// requires p.mu be held.
+func (p *http2pipe) closeDoneLocked() {
+	if p.donec == nil {
+		return
+	}
+	// Close if unclosed. This isn't racy since we always
+	// hold p.mu while closing.
+	select {
+	case <-p.donec:
+	default:
+		close(p.donec)
+	}
+}
+
+// Err returns the error (if any) first set by BreakWithError or CloseWithError.
+func (p *http2pipe) Err() error {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	if p.breakErr != nil {
+		return p.breakErr
+	}
+	return p.err
+}
+
+// Done returns a channel which is closed if and when this pipe is closed
+// with CloseWithError.
+func (p *http2pipe) Done() <-chan struct{} {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	if p.donec == nil {
+		p.donec = make(chan struct{})
+		if p.err != nil || p.breakErr != nil {
+			// Already hit an error.
+			p.closeDoneLocked()
+		}
+	}
+	return p.donec
+}
+
+const (
+	http2prefaceTimeout         = 10 * time.Second
+	http2firstSettingsTimeout   = 2 * time.Second // should be in-flight with preface anyway
+	http2handlerChunkWriteSize  = 4 << 10
+	http2defaultMaxStreams      = 250 // TODO: make this 100 as the GFE seems to?
+	http2maxQueuedControlFrames = 10000
+)
+
+var (
+	http2errClientDisconnected = errors.New("client disconnected")
+	http2errClosedBody         = errors.New("body closed by handler")
+	http2errHandlerComplete    = errors.New("http2: request body closed due to handler exiting")
+	http2errStreamClosed       = errors.New("http2: stream closed")
+)
+
+var http2responseWriterStatePool = sync.Pool{
+	New: func() interface{} {
+		rws := &http2responseWriterState{}
+		rws.bw = bufio.NewWriterSize(http2chunkWriter{rws}, http2handlerChunkWriteSize)
+		return rws
+	},
+}
+
+// Test hooks.
+var (
+	http2testHookOnConn        func()
+	http2testHookGetServerConn func(*http2serverConn)
+	http2testHookOnPanicMu     *sync.Mutex // nil except in tests
+	http2testHookOnPanic       func(sc *http2serverConn, panicVal interface{}) (rePanic bool)
+)
+
+// Server is an HTTP/2 server.
+type http2Server struct {
+	// MaxHandlers limits the number of http.Handler ServeHTTP goroutines
+	// which may run at a time over all connections.
+	// Negative or zero no limit.
+	// TODO: implement
+	MaxHandlers int
+
+	// MaxConcurrentStreams optionally specifies the number of
+	// concurrent streams that each client may have open at a
+	// time. This is unrelated to the number of http.Handler goroutines
+	// which may be active globally, which is MaxHandlers.
+	// If zero, MaxConcurrentStreams defaults to at least 100, per
+	// the HTTP/2 spec's recommendations.
+	MaxConcurrentStreams uint32
+
+	// MaxReadFrameSize optionally specifies the largest frame
+	// this server is willing to read. A valid value is between
+	// 16k and 16M, inclusive. If zero or otherwise invalid, a
+	// default value is used.
+	MaxReadFrameSize uint32
+
+	// PermitProhibitedCipherSuites, if true, permits the use of
+	// cipher suites prohibited by the HTTP/2 spec.
+	PermitProhibitedCipherSuites bool
+
+	// IdleTimeout specifies how long until idle clients should be
+	// closed with a GOAWAY frame. PING frames are not considered
+	// activity for the purposes of IdleTimeout.
+	IdleTimeout time.Duration
+
+	// MaxUploadBufferPerConnection is the size of the initial flow
+	// control window for each connections. The HTTP/2 spec does not
+	// allow this to be smaller than 65535 or larger than 2^32-1.
+	// If the value is outside this range, a default value will be
+	// used instead.
+	MaxUploadBufferPerConnection int32
+
+	// MaxUploadBufferPerStream is the size of the initial flow control
+	// window for each stream. The HTTP/2 spec does not allow this to
+	// be larger than 2^32-1. If the value is zero or larger than the
+	// maximum, a default value will be used instead.
+	MaxUploadBufferPerStream int32
+
+	// NewWriteScheduler constructs a write scheduler for a connection.
+	// If nil, a default scheduler is chosen.
+	NewWriteScheduler func() http2WriteScheduler
+
+	// CountError, if non-nil, is called on HTTP/2 server errors.
+	// It's intended to increment a metric for monitoring, such
+	// as an expvar or Prometheus metric.
+	// The errType consists of only ASCII word characters.
+	CountError func(errType string)
+
+	// Internal state. This is a pointer (rather than embedded directly)
+	// so that we don't embed a Mutex in this struct, which will make the
+	// struct non-copyable, which might break some callers.
+	state *http2serverInternalState
+}
+
+func (s *http2Server) initialConnRecvWindowSize() int32 {
+	if s.MaxUploadBufferPerConnection > http2initialWindowSize {
+		return s.MaxUploadBufferPerConnection
+	}
+	return 1 << 20
+}
+
+func (s *http2Server) initialStreamRecvWindowSize() int32 {
+	if s.MaxUploadBufferPerStream > 0 {
+		return s.MaxUploadBufferPerStream
+	}
+	return 1 << 20
+}
+
+func (s *http2Server) maxReadFrameSize() uint32 {
+	if v := s.MaxReadFrameSize; v >= http2minMaxFrameSize && v <= http2maxFrameSize {
+		return v
+	}
+	return http2defaultMaxReadFrameSize
+}
+
+func (s *http2Server) maxConcurrentStreams() uint32 {
+	if v := s.MaxConcurrentStreams; v > 0 {
+		return v
+	}
+	return http2defaultMaxStreams
+}
+
+// maxQueuedControlFrames is the maximum number of control frames like
+// SETTINGS, PING and RST_STREAM that will be queued for writing before
+// the connection is closed to prevent memory exhaustion attacks.
+func (s *http2Server) maxQueuedControlFrames() int {
+	// TODO: if anybody asks, add a Server field, and remember to define the
+	// behavior of negative values.
+	return http2maxQueuedControlFrames
+}
+
+type http2serverInternalState struct {
+	mu          sync.Mutex
+	activeConns map[*http2serverConn]struct{}
+}
+
+func (s *http2serverInternalState) registerConn(sc *http2serverConn) {
+	if s == nil {
+		return // if the Server was used without calling ConfigureServer
+	}
+	s.mu.Lock()
+	s.activeConns[sc] = struct{}{}
+	s.mu.Unlock()
+}
+
+func (s *http2serverInternalState) unregisterConn(sc *http2serverConn) {
+	if s == nil {
+		return // if the Server was used without calling ConfigureServer
+	}
+	s.mu.Lock()
+	delete(s.activeConns, sc)
+	s.mu.Unlock()
+}
+
+func (s *http2serverInternalState) startGracefulShutdown() {
+	if s == nil {
+		return // if the Server was used without calling ConfigureServer
+	}
+	s.mu.Lock()
+	for sc := range s.activeConns {
+		sc.startGracefulShutdown()
+	}
+	s.mu.Unlock()
+}
+
+// ConfigureServer adds HTTP/2 support to a net/http Server.
+//
+// The configuration conf may be nil.
+//
+// ConfigureServer must be called before s begins serving.
+func http2ConfigureServer(s *Server, conf *http2Server) error {
+	if s == nil {
+		panic("nil *http.Server")
+	}
+	if conf == nil {
+		conf = new(http2Server)
+	}
+	conf.state = &http2serverInternalState{activeConns: make(map[*http2serverConn]struct{})}
+	if h1, h2 := s, conf; h2.IdleTimeout == 0 {
+		if h1.IdleTimeout != 0 {
+			h2.IdleTimeout = h1.IdleTimeout
+		} else {
+			h2.IdleTimeout = h1.ReadTimeout
+		}
+	}
+	s.RegisterOnShutdown(conf.state.startGracefulShutdown)
+
+	if s.TLSConfig == nil {
+		s.TLSConfig = new(tls.Config)
+	} else if s.TLSConfig.CipherSuites != nil && s.TLSConfig.MinVersion < tls.VersionTLS13 {
+		// If they already provided a TLS 1.0–1.2 CipherSuite list, return an
+		// error if it is missing ECDHE_RSA_WITH_AES_128_GCM_SHA256 or
+		// ECDHE_ECDSA_WITH_AES_128_GCM_SHA256.
+		haveRequired := false
+		for _, cs := range s.TLSConfig.CipherSuites {
+			switch cs {
+			case tls.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
+				// Alternative MTI cipher to not discourage ECDSA-only servers.
+				// See http://golang.org/cl/30721 for further information.
+				tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256:
+				haveRequired = true
+			}
+		}
+		if !haveRequired {
+			return fmt.Errorf("http2: TLSConfig.CipherSuites is missing an HTTP/2-required AES_128_GCM_SHA256 cipher (need at least one of TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 or TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256)")
+		}
+	}
+
+	// Note: not setting MinVersion to tls.VersionTLS12,
+	// as we don't want to interfere with HTTP/1.1 traffic
+	// on the user's server. We enforce TLS 1.2 later once
+	// we accept a connection. Ideally this should be done
+	// during next-proto selection, but using TLS <1.2 with
+	// HTTP/2 is still the client's bug.
+
+	s.TLSConfig.PreferServerCipherSuites = true
+
+	if !http2strSliceContains(s.TLSConfig.NextProtos, http2NextProtoTLS) {
+		s.TLSConfig.NextProtos = append(s.TLSConfig.NextProtos, http2NextProtoTLS)
+	}
+	if !http2strSliceContains(s.TLSConfig.NextProtos, "http/1.1") {
+		s.TLSConfig.NextProtos = append(s.TLSConfig.NextProtos, "http/1.1")
+	}
+
+	if s.TLSNextProto == nil {
+		s.TLSNextProto = map[string]func(*Server, *tls.Conn, Handler){}
+	}
+	protoHandler := func(hs *Server, c *tls.Conn, h Handler) {
+		if http2testHookOnConn != nil {
+			http2testHookOnConn()
+		}
+		// The TLSNextProto interface predates contexts, so
+		// the net/http package passes down its per-connection
+		// base context via an exported but unadvertised
+		// method on the Handler. This is for internal
+		// net/http<=>http2 use only.
+		var ctx context.Context
+		type baseContexter interface {
+			BaseContext() context.Context
+		}
+		if bc, ok := h.(baseContexter); ok {
+			ctx = bc.BaseContext()
+		}
+		conf.ServeConn(c, &http2ServeConnOpts{
+			Context:    ctx,
+			Handler:    h,
+			BaseConfig: hs,
+		})
+	}
+	s.TLSNextProto[http2NextProtoTLS] = protoHandler
+	return nil
+}
+
+// ServeConnOpts are options for the Server.ServeConn method.
+type http2ServeConnOpts struct {
+	// Context is the base context to use.
+	// If nil, context.Background is used.
+	Context context.Context
+
+	// BaseConfig optionally sets the base configuration
+	// for values. If nil, defaults are used.
+	BaseConfig *Server
+
+	// Handler specifies which handler to use for processing
+	// requests. If nil, BaseConfig.Handler is used. If BaseConfig
+	// or BaseConfig.Handler is nil, http.DefaultServeMux is used.
+	Handler Handler
+}
+
+func (o *http2ServeConnOpts) context() context.Context {
+	if o != nil && o.Context != nil {
+		return o.Context
+	}
+	return context.Background()
+}
+
+func (o *http2ServeConnOpts) baseConfig() *Server {
+	if o != nil && o.BaseConfig != nil {
+		return o.BaseConfig
+	}
+	return new(Server)
+}
+
+func (o *http2ServeConnOpts) handler() Handler {
+	if o != nil {
+		if o.Handler != nil {
+			return o.Handler
+		}
+		if o.BaseConfig != nil && o.BaseConfig.Handler != nil {
+			return o.BaseConfig.Handler
+		}
+	}
+	return DefaultServeMux
+}
+
+// ServeConn serves HTTP/2 requests on the provided connection and
+// blocks until the connection is no longer readable.
+//
+// ServeConn starts speaking HTTP/2 assuming that c has not had any
+// reads or writes. It writes its initial settings frame and expects
+// to be able to read the preface and settings frame from the
+// client. If c has a ConnectionState method like a *tls.Conn, the
+// ConnectionState is used to verify the TLS ciphersuite and to set
+// the Request.TLS field in Handlers.
+//
+// ServeConn does not support h2c by itself. Any h2c support must be
+// implemented in terms of providing a suitably-behaving net.Conn.
+//
+// The opts parameter is optional. If nil, default values are used.
+func (s *http2Server) ServeConn(c net.Conn, opts *http2ServeConnOpts) {
+	baseCtx, cancel := http2serverConnBaseContext(c, opts)
+	defer cancel()
+
+	sc := &http2serverConn{
+		srv:                         s,
+		hs:                          opts.baseConfig(),
+		conn:                        c,
+		baseCtx:                     baseCtx,
+		remoteAddrStr:               c.RemoteAddr().String(),
+		bw:                          http2newBufferedWriter(c),
+		handler:                     opts.handler(),
+		streams:                     make(map[uint32]*http2stream),
+		readFrameCh:                 make(chan http2readFrameResult),
+		wantWriteFrameCh:            make(chan http2FrameWriteRequest, 8),
+		serveMsgCh:                  make(chan interface{}, 8),
+		wroteFrameCh:                make(chan http2frameWriteResult, 1), // buffered; one send in writeFrameAsync
+		bodyReadCh:                  make(chan http2bodyReadMsg),         // buffering doesn't matter either way
+		doneServing:                 make(chan struct{}),
+		clientMaxStreams:            math.MaxUint32, // Section 6.5.2: "Initially, there is no limit to this value"
+		advMaxStreams:               s.maxConcurrentStreams(),
+		initialStreamSendWindowSize: http2initialWindowSize,
+		maxFrameSize:                http2initialMaxFrameSize,
+		headerTableSize:             http2initialHeaderTableSize,
+		serveG:                      http2newGoroutineLock(),
+		pushEnabled:                 true,
+	}
+
+	s.state.registerConn(sc)
+	defer s.state.unregisterConn(sc)
+
+	// The net/http package sets the write deadline from the
+	// http.Server.WriteTimeout during the TLS handshake, but then
+	// passes the connection off to us with the deadline already set.
+	// Write deadlines are set per stream in serverConn.newStream.
+	// Disarm the net.Conn write deadline here.
+	if sc.hs.WriteTimeout != 0 {
+		sc.conn.SetWriteDeadline(time.Time{})
+	}
+
+	if s.NewWriteScheduler != nil {
+		sc.writeSched = s.NewWriteScheduler()
+	} else {
+		sc.writeSched = http2NewPriorityWriteScheduler(nil)
+	}
+
+	// These start at the RFC-specified defaults. If there is a higher
+	// configured value for inflow, that will be updated when we send a
+	// WINDOW_UPDATE shortly after sending SETTINGS.
+	sc.flow.add(http2initialWindowSize)
+	sc.inflow.add(http2initialWindowSize)
+	sc.hpackEncoder = hpack.NewEncoder(&sc.headerWriteBuf)
+
+	fr := http2NewFramer(sc.bw, c)
+	if s.CountError != nil {
+		fr.countError = s.CountError
+	}
+	fr.ReadMetaHeaders = hpack.NewDecoder(http2initialHeaderTableSize, nil)
+	fr.MaxHeaderListSize = sc.maxHeaderListSize()
+	fr.SetMaxReadFrameSize(s.maxReadFrameSize())
+	sc.framer = fr
+
+	if tc, ok := c.(http2connectionStater); ok {
+		sc.tlsState = new(tls.ConnectionState)
+		*sc.tlsState = tc.ConnectionState()
+		// 9.2 Use of TLS Features
+		// An implementation of HTTP/2 over TLS MUST use TLS
+		// 1.2 or higher with the restrictions on feature set
+		// and cipher suite described in this section. Due to
+		// implementation limitations, it might not be
+		// possible to fail TLS negotiation. An endpoint MUST
+		// immediately terminate an HTTP/2 connection that
+		// does not meet the TLS requirements described in
+		// this section with a connection error (Section
+		// 5.4.1) of type INADEQUATE_SECURITY.
+		if sc.tlsState.Version < tls.VersionTLS12 {
+			sc.rejectConn(http2ErrCodeInadequateSecurity, "TLS version too low")
+			return
+		}
+
+		if sc.tlsState.ServerName == "" {
+			// Client must use SNI, but we don't enforce that anymore,
+			// since it was causing problems when connecting to bare IP
+			// addresses during development.
+			//
+			// TODO: optionally enforce? Or enforce at the time we receive
+			// a new request, and verify the ServerName matches the :authority?
+			// But that precludes proxy situations, perhaps.
+			//
+			// So for now, do nothing here again.
+		}
+
+		if !s.PermitProhibitedCipherSuites && http2isBadCipher(sc.tlsState.CipherSuite) {
+			// "Endpoints MAY choose to generate a connection error
+			// (Section 5.4.1) of type INADEQUATE_SECURITY if one of
+			// the prohibited cipher suites are negotiated."
+			//
+			// We choose that. In my opinion, the spec is weak
+			// here. It also says both parties must support at least
+			// TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 so there's no
+			// excuses here. If we really must, we could allow an
+			// "AllowInsecureWeakCiphers" option on the server later.
+			// Let's see how it plays out first.
+			sc.rejectConn(http2ErrCodeInadequateSecurity, fmt.Sprintf("Prohibited TLS 1.2 Cipher Suite: %x", sc.tlsState.CipherSuite))
+			return
+		}
+	}
+
+	if hook := http2testHookGetServerConn; hook != nil {
+		hook(sc)
+	}
+	sc.serve()
+}
+
+func http2serverConnBaseContext(c net.Conn, opts *http2ServeConnOpts) (ctx context.Context, cancel func()) {
+	ctx, cancel = context.WithCancel(opts.context())
+	ctx = context.WithValue(ctx, LocalAddrContextKey, c.LocalAddr())
+	if hs := opts.baseConfig(); hs != nil {
+		ctx = context.WithValue(ctx, ServerContextKey, hs)
+	}
+	return
+}
+
+func (sc *http2serverConn) rejectConn(err http2ErrCode, debug string) {
+	sc.vlogf("http2: server rejecting conn: %v, %s", err, debug)
+	// ignoring errors. hanging up anyway.
+	sc.framer.WriteGoAway(0, err, []byte(debug))
+	sc.bw.Flush()
+	sc.conn.Close()
+}
+
+type http2serverConn struct {
+	// Immutable:
+	srv              *http2Server
+	hs               *Server
+	conn             net.Conn
+	bw               *http2bufferedWriter // writing to conn
+	handler          Handler
+	baseCtx          context.Context
+	framer           *http2Framer
+	doneServing      chan struct{}               // closed when serverConn.serve ends
+	readFrameCh      chan http2readFrameResult   // written by serverConn.readFrames
+	wantWriteFrameCh chan http2FrameWriteRequest // from handlers -> serve
+	wroteFrameCh     chan http2frameWriteResult  // from writeFrameAsync -> serve, tickles more frame writes
+	bodyReadCh       chan http2bodyReadMsg       // from handlers -> serve
+	serveMsgCh       chan interface{}            // misc messages & code to send to / run on the serve loop
+	flow             http2flow                   // conn-wide (not stream-specific) outbound flow control
+	inflow           http2flow                   // conn-wide inbound flow control
+	tlsState         *tls.ConnectionState        // shared by all handlers, like net/http
+	remoteAddrStr    string
+	writeSched       http2WriteScheduler
+
+	// Everything following is owned by the serve loop; use serveG.check():
+	serveG                      http2goroutineLock // used to verify funcs are on serve()
+	pushEnabled                 bool
+	sawFirstSettings            bool // got the initial SETTINGS frame after the preface
+	needToSendSettingsAck       bool
+	unackedSettings             int    // how many SETTINGS have we sent without ACKs?
+	queuedControlFrames         int    // control frames in the writeSched queue
+	clientMaxStreams            uint32 // SETTINGS_MAX_CONCURRENT_STREAMS from client (our PUSH_PROMISE limit)
+	advMaxStreams               uint32 // our SETTINGS_MAX_CONCURRENT_STREAMS advertised the client
+	curClientStreams            uint32 // number of open streams initiated by the client
+	curPushedStreams            uint32 // number of open streams initiated by server push
+	maxClientStreamID           uint32 // max ever seen from client (odd), or 0 if there have been no client requests
+	maxPushPromiseID            uint32 // ID of the last push promise (even), or 0 if there have been no pushes
+	streams                     map[uint32]*http2stream
+	initialStreamSendWindowSize int32
+	maxFrameSize                int32
+	headerTableSize             uint32
+	peerMaxHeaderListSize       uint32            // zero means unknown (default)
+	canonHeader                 map[string]string // http2-lower-case -> Go-Canonical-Case
+	writingFrame                bool              // started writing a frame (on serve goroutine or separate)
+	writingFrameAsync           bool              // started a frame on its own goroutine but haven't heard back on wroteFrameCh
+	needsFrameFlush             bool              // last frame write wasn't a flush
+	inGoAway                    bool              // we've started to or sent GOAWAY
+	inFrameScheduleLoop         bool              // whether we're in the scheduleFrameWrite loop
+	needToSendGoAway            bool              // we need to schedule a GOAWAY frame write
+	goAwayCode                  http2ErrCode
+	shutdownTimer               *time.Timer // nil until used
+	idleTimer                   *time.Timer // nil if unused
+
+	// Owned by the writeFrameAsync goroutine:
+	headerWriteBuf bytes.Buffer
+	hpackEncoder   *hpack.Encoder
+
+	// Used by startGracefulShutdown.
+	shutdownOnce sync.Once
+}
+
+func (sc *http2serverConn) maxHeaderListSize() uint32 {
+	n := sc.hs.MaxHeaderBytes
+	if n <= 0 {
+		n = DefaultMaxHeaderBytes
+	}
+	// http2's count is in a slightly different unit and includes 32 bytes per pair.
+	// So, take the net/http.Server value and pad it up a bit, assuming 10 headers.
+	const perFieldOverhead = 32 // per http2 spec
+	const typicalHeaders = 10   // conservative
+	return uint32(n + typicalHeaders*perFieldOverhead)
+}
+
+func (sc *http2serverConn) curOpenStreams() uint32 {
+	sc.serveG.check()
+	return sc.curClientStreams + sc.curPushedStreams
+}
+
+// stream represents a stream. This is the minimal metadata needed by
+// the serve goroutine. Most of the actual stream state is owned by
+// the http.Handler's goroutine in the responseWriter. Because the
+// responseWriter's responseWriterState is recycled at the end of a
+// handler, this struct intentionally has no pointer to the
+// *responseWriter{,State} itself, as the Handler ending nils out the
+// responseWriter's state field.
+type http2stream struct {
+	// immutable:
+	sc        *http2serverConn
+	id        uint32
+	body      *http2pipe       // non-nil if expecting DATA frames
+	cw        http2closeWaiter // closed wait stream transitions to closed state
+	ctx       context.Context
+	cancelCtx func()
+
+	// owned by serverConn's serve loop:
+	bodyBytes        int64     // body bytes seen so far
+	declBodyBytes    int64     // or -1 if undeclared
+	flow             http2flow // limits writing from Handler to client
+	inflow           http2flow // what the client is allowed to POST/etc to us
+	state            http2streamState
+	resetQueued      bool        // RST_STREAM queued for write; set by sc.resetStream
+	gotTrailerHeader bool        // HEADER frame for trailers was seen
+	wroteHeaders     bool        // whether we wrote headers (not status 100)
+	writeDeadline    *time.Timer // nil if unused
+
+	trailer    Header // accumulated trailers
+	reqTrailer Header // handler's Request.Trailer
+}
+
+func (sc *http2serverConn) Framer() *http2Framer { return sc.framer }
+
+func (sc *http2serverConn) CloseConn() error { return sc.conn.Close() }
+
+func (sc *http2serverConn) Flush() error { return sc.bw.Flush() }
+
+func (sc *http2serverConn) HeaderEncoder() (*hpack.Encoder, *bytes.Buffer) {
+	return sc.hpackEncoder, &sc.headerWriteBuf
+}
+
+func (sc *http2serverConn) state(streamID uint32) (http2streamState, *http2stream) {
+	sc.serveG.check()
+	// http://tools.ietf.org/html/rfc7540#section-5.1
+	if st, ok := sc.streams[streamID]; ok {
+		return st.state, st
+	}
+	// "The first use of a new stream identifier implicitly closes all
+	// streams in the "idle" state that might have been initiated by
+	// that peer with a lower-valued stream identifier. For example, if
+	// a client sends a HEADERS frame on stream 7 without ever sending a
+	// frame on stream 5, then stream 5 transitions to the "closed"
+	// state when the first frame for stream 7 is sent or received."
+	if streamID%2 == 1 {
+		if streamID <= sc.maxClientStreamID {
+			return http2stateClosed, nil
+		}
+	} else {
+		if streamID <= sc.maxPushPromiseID {
+			return http2stateClosed, nil
+		}
+	}
+	return http2stateIdle, nil
+}
+
+// setConnState calls the net/http ConnState hook for this connection, if configured.
+// Note that the net/http package does StateNew and StateClosed for us.
+// There is currently no plan for StateHijacked or hijacking HTTP/2 connections.
+func (sc *http2serverConn) setConnState(state ConnState) {
+	if sc.hs.ConnState != nil {
+		sc.hs.ConnState(sc.conn, state)
+	}
+}
+
+func (sc *http2serverConn) vlogf(format string, args ...interface{}) {
+	if http2VerboseLogs {
+		sc.logf(format, args...)
+	}
+}
+
+func (sc *http2serverConn) logf(format string, args ...interface{}) {
+	if lg := sc.hs.ErrorLog; lg != nil {
+		lg.Printf(format, args...)
+	} else {
+		log.Printf(format, args...)
+	}
+}
+
+// errno returns v's underlying uintptr, else 0.
+//
+// TODO: remove this helper function once http2 can use build
+// tags. See comment in isClosedConnError.
+func http2errno(v error) uintptr {
+	if rv := reflect.ValueOf(v); rv.Kind() == reflect.Uintptr {
+		return uintptr(rv.Uint())
+	}
+	return 0
+}
+
+// isClosedConnError reports whether err is an error from use of a closed
+// network connection.
+func http2isClosedConnError(err error) bool {
+	if err == nil {
+		return false
+	}
+
+	// TODO: remove this string search and be more like the Windows
+	// case below. That might involve modifying the standard library
+	// to return better error types.
+	str := err.Error()
+	if strings.Contains(str, "use of closed network connection") {
+		return true
+	}
+
+	// TODO(bradfitz): x/tools/cmd/bundle doesn't really support
+	// build tags, so I can't make an http2_windows.go file with
+	// Windows-specific stuff. Fix that and move this, once we
+	// have a way to bundle this into std's net/http somehow.
+	if runtime.GOOS == "windows" {
+		if oe, ok := err.(*net.OpError); ok && oe.Op == "read" {
+			if se, ok := oe.Err.(*os.SyscallError); ok && se.Syscall == "wsarecv" {
+				const WSAECONNABORTED = 10053
+				const WSAECONNRESET = 10054
+				if n := http2errno(se.Err); n == WSAECONNRESET || n == WSAECONNABORTED {
+					return true
+				}
+			}
+		}
+	}
+	return false
+}
+
+func (sc *http2serverConn) condlogf(err error, format string, args ...interface{}) {
+	if err == nil {
+		return
+	}
+	if err == io.EOF || err == io.ErrUnexpectedEOF || http2isClosedConnError(err) || err == http2errPrefaceTimeout {
+		// Boring, expected errors.
+		sc.vlogf(format, args...)
+	} else {
+		sc.logf(format, args...)
+	}
+}
+
+func (sc *http2serverConn) canonicalHeader(v string) string {
+	sc.serveG.check()
+	http2buildCommonHeaderMapsOnce()
+	cv, ok := http2commonCanonHeader[v]
+	if ok {
+		return cv
+	}
+	cv, ok = sc.canonHeader[v]
+	if ok {
+		return cv
+	}
+	if sc.canonHeader == nil {
+		sc.canonHeader = make(map[string]string)
+	}
+	cv = CanonicalHeaderKey(v)
+	// maxCachedCanonicalHeaders is an arbitrarily-chosen limit on the number of
+	// entries in the canonHeader cache. This should be larger than the number
+	// of unique, uncommon header keys likely to be sent by the peer, while not
+	// so high as to permit unreasonable memory usage if the peer sends an unbounded
+	// number of unique header keys.
+	const maxCachedCanonicalHeaders = 32
+	if len(sc.canonHeader) < maxCachedCanonicalHeaders {
+		sc.canonHeader[v] = cv
+	}
+	return cv
+}
+
+type http2readFrameResult struct {
+	f   http2Frame // valid until readMore is called
+	err error
+
+	// readMore should be called once the consumer no longer needs or
+	// retains f. After readMore, f is invalid and more frames can be
+	// read.
+	readMore func()
+}
+
+// readFrames is the loop that reads incoming frames.
+// It takes care to only read one frame at a time, blocking until the
+// consumer is done with the frame.
+// It's run on its own goroutine.
+func (sc *http2serverConn) readFrames() {
+	gate := make(http2gate)
+	gateDone := gate.Done
+	for {
+		f, err := sc.framer.ReadFrame()
+		select {
+		case sc.readFrameCh <- http2readFrameResult{f, err, gateDone}:
+		case <-sc.doneServing:
+			return
+		}
+		select {
+		case <-gate:
+		case <-sc.doneServing:
+			return
+		}
+		if http2terminalReadFrameError(err) {
+			return
+		}
+	}
+}
+
+// frameWriteResult is the message passed from writeFrameAsync to the serve goroutine.
+type http2frameWriteResult struct {
+	_   http2incomparable
+	wr  http2FrameWriteRequest // what was written (or attempted)
+	err error                  // result of the writeFrame call
+}
+
+// writeFrameAsync runs in its own goroutine and writes a single frame
+// and then reports when it's done.
+// At most one goroutine can be running writeFrameAsync at a time per
+// serverConn.
+func (sc *http2serverConn) writeFrameAsync(wr http2FrameWriteRequest) {
+	err := wr.write.writeFrame(sc)
+	sc.wroteFrameCh <- http2frameWriteResult{wr: wr, err: err}
+}
+
+func (sc *http2serverConn) closeAllStreamsOnConnClose() {
+	sc.serveG.check()
+	for _, st := range sc.streams {
+		sc.closeStream(st, http2errClientDisconnected)
+	}
+}
+
+func (sc *http2serverConn) stopShutdownTimer() {
+	sc.serveG.check()
+	if t := sc.shutdownTimer; t != nil {
+		t.Stop()
+	}
+}
+
+func (sc *http2serverConn) notePanic() {
+	// Note: this is for serverConn.serve panicking, not http.Handler code.
+	if http2testHookOnPanicMu != nil {
+		http2testHookOnPanicMu.Lock()
+		defer http2testHookOnPanicMu.Unlock()
+	}
+	if http2testHookOnPanic != nil {
+		if e := recover(); e != nil {
+			if http2testHookOnPanic(sc, e) {
+				panic(e)
+			}
+		}
+	}
+}
+
+func (sc *http2serverConn) serve() {
+	sc.serveG.check()
+	defer sc.notePanic()
+	defer sc.conn.Close()
+	defer sc.closeAllStreamsOnConnClose()
+	defer sc.stopShutdownTimer()
+	defer close(sc.doneServing) // unblocks handlers trying to send
+
+	if http2VerboseLogs {
+		sc.vlogf("http2: server connection from %v on %p", sc.conn.RemoteAddr(), sc.hs)
+	}
+
+	sc.writeFrame(http2FrameWriteRequest{
+		write: http2writeSettings{
+			{http2SettingMaxFrameSize, sc.srv.maxReadFrameSize()},
+			{http2SettingMaxConcurrentStreams, sc.advMaxStreams},
+			{http2SettingMaxHeaderListSize, sc.maxHeaderListSize()},
+			{http2SettingInitialWindowSize, uint32(sc.srv.initialStreamRecvWindowSize())},
+		},
+	})
+	sc.unackedSettings++
+
+	// Each connection starts with initialWindowSize inflow tokens.
+	// If a higher value is configured, we add more tokens.
+	if diff := sc.srv.initialConnRecvWindowSize() - http2initialWindowSize; diff > 0 {
+		sc.sendWindowUpdate(nil, int(diff))
+	}
+
+	if err := sc.readPreface(); err != nil {
+		sc.condlogf(err, "http2: server: error reading preface from client %v: %v", sc.conn.RemoteAddr(), err)
+		return
+	}
+	// Now that we've got the preface, get us out of the
+	// "StateNew" state. We can't go directly to idle, though.
+	// Active means we read some data and anticipate a request. We'll
+	// do another Active when we get a HEADERS frame.
+	sc.setConnState(StateActive)
+	sc.setConnState(StateIdle)
+
+	if sc.srv.IdleTimeout != 0 {
+		sc.idleTimer = time.AfterFunc(sc.srv.IdleTimeout, sc.onIdleTimer)
+		defer sc.idleTimer.Stop()
+	}
+
+	go sc.readFrames() // closed by defer sc.conn.Close above
+
+	settingsTimer := time.AfterFunc(http2firstSettingsTimeout, sc.onSettingsTimer)
+	defer settingsTimer.Stop()
+
+	loopNum := 0
+	for {
+		loopNum++
+		select {
+		case wr := <-sc.wantWriteFrameCh:
+			if se, ok := wr.write.(http2StreamError); ok {
+				sc.resetStream(se)
+				break
+			}
+			sc.writeFrame(wr)
+		case res := <-sc.wroteFrameCh:
+			sc.wroteFrame(res)
+		case res := <-sc.readFrameCh:
+			// Process any written frames before reading new frames from the client since a
+			// written frame could have triggered a new stream to be started.
+			if sc.writingFrameAsync {
+				select {
+				case wroteRes := <-sc.wroteFrameCh:
+					sc.wroteFrame(wroteRes)
+				default:
+				}
+			}
+			if !sc.processFrameFromReader(res) {
+				return
+			}
+			res.readMore()
+			if settingsTimer != nil {
+				settingsTimer.Stop()
+				settingsTimer = nil
+			}
+		case m := <-sc.bodyReadCh:
+			sc.noteBodyRead(m.st, m.n)
+		case msg := <-sc.serveMsgCh:
+			switch v := msg.(type) {
+			case func(int):
+				v(loopNum) // for testing
+			case *http2serverMessage:
+				switch v {
+				case http2settingsTimerMsg:
+					sc.logf("timeout waiting for SETTINGS frames from %v", sc.conn.RemoteAddr())
+					return
+				case http2idleTimerMsg:
+					sc.vlogf("connection is idle")
+					sc.goAway(http2ErrCodeNo)
+				case http2shutdownTimerMsg:
+					sc.vlogf("GOAWAY close timer fired; closing conn from %v", sc.conn.RemoteAddr())
+					return
+				case http2gracefulShutdownMsg:
+					sc.startGracefulShutdownInternal()
+				default:
+					panic("unknown timer")
+				}
+			case *http2startPushRequest:
+				sc.startPush(v)
+			default:
+				panic(fmt.Sprintf("unexpected type %T", v))
+			}
+		}
+
+		// If the peer is causing us to generate a lot of control frames,
+		// but not reading them from us, assume they are trying to make us
+		// run out of memory.
+		if sc.queuedControlFrames > sc.srv.maxQueuedControlFrames() {
+			sc.vlogf("http2: too many control frames in send queue, closing connection")
+			return
+		}
+
+		// Start the shutdown timer after sending a GOAWAY. When sending GOAWAY
+		// with no error code (graceful shutdown), don't start the timer until
+		// all open streams have been completed.
+		sentGoAway := sc.inGoAway && !sc.needToSendGoAway && !sc.writingFrame
+		gracefulShutdownComplete := sc.goAwayCode == http2ErrCodeNo && sc.curOpenStreams() == 0
+		if sentGoAway && sc.shutdownTimer == nil && (sc.goAwayCode != http2ErrCodeNo || gracefulShutdownComplete) {
+			sc.shutDownIn(http2goAwayTimeout)
+		}
+	}
+}
+
+func (sc *http2serverConn) awaitGracefulShutdown(sharedCh <-chan struct{}, privateCh chan struct{}) {
+	select {
+	case <-sc.doneServing:
+	case <-sharedCh:
+		close(privateCh)
+	}
+}
+
+type http2serverMessage int
+
+// Message values sent to serveMsgCh.
+var (
+	http2settingsTimerMsg    = new(http2serverMessage)
+	http2idleTimerMsg        = new(http2serverMessage)
+	http2shutdownTimerMsg    = new(http2serverMessage)
+	http2gracefulShutdownMsg = new(http2serverMessage)
+)
+
+func (sc *http2serverConn) onSettingsTimer() { sc.sendServeMsg(http2settingsTimerMsg) }
+
+func (sc *http2serverConn) onIdleTimer() { sc.sendServeMsg(http2idleTimerMsg) }
+
+func (sc *http2serverConn) onShutdownTimer() { sc.sendServeMsg(http2shutdownTimerMsg) }
+
+func (sc *http2serverConn) sendServeMsg(msg interface{}) {
+	sc.serveG.checkNotOn() // NOT
+	select {
+	case sc.serveMsgCh <- msg:
+	case <-sc.doneServing:
+	}
+}
+
+var http2errPrefaceTimeout = errors.New("timeout waiting for client preface")
+
+// readPreface reads the ClientPreface greeting from the peer or
+// returns errPrefaceTimeout on timeout, or an error if the greeting
+// is invalid.
+func (sc *http2serverConn) readPreface() error {
+	errc := make(chan error, 1)
+	go func() {
+		// Read the client preface
+		buf := make([]byte, len(http2ClientPreface))
+		if _, err := io.ReadFull(sc.conn, buf); err != nil {
+			errc <- err
+		} else if !bytes.Equal(buf, http2clientPreface) {
+			errc <- fmt.Errorf("bogus greeting %q", buf)
+		} else {
+			errc <- nil
+		}
+	}()
+	timer := time.NewTimer(http2prefaceTimeout) // TODO: configurable on *Server?
+	defer timer.Stop()
+	select {
+	case <-timer.C:
+		return http2errPrefaceTimeout
+	case err := <-errc:
+		if err == nil {
+			if http2VerboseLogs {
+				sc.vlogf("http2: server: client %v said hello", sc.conn.RemoteAddr())
+			}
+		}
+		return err
+	}
+}
+
+var http2errChanPool = sync.Pool{
+	New: func() interface{} { return make(chan error, 1) },
+}
+
+var http2writeDataPool = sync.Pool{
+	New: func() interface{} { return new(http2writeData) },
+}
+
+// writeDataFromHandler writes DATA response frames from a handler on
+// the given stream.
+func (sc *http2serverConn) writeDataFromHandler(stream *http2stream, data []byte, endStream bool) error {
+	ch := http2errChanPool.Get().(chan error)
+	writeArg := http2writeDataPool.Get().(*http2writeData)
+	*writeArg = http2writeData{stream.id, data, endStream}
+	err := sc.writeFrameFromHandler(http2FrameWriteRequest{
+		write:  writeArg,
+		stream: stream,
+		done:   ch,
+	})
+	if err != nil {
+		return err
+	}
+	var frameWriteDone bool // the frame write is done (successfully or not)
+	select {
+	case err = <-ch:
+		frameWriteDone = true
+	case <-sc.doneServing:
+		return http2errClientDisconnected
+	case <-stream.cw:
+		// If both ch and stream.cw were ready (as might
+		// happen on the final Write after an http.Handler
+		// ends), prefer the write result. Otherwise this
+		// might just be us successfully closing the stream.
+		// The writeFrameAsync and serve goroutines guarantee
+		// that the ch send will happen before the stream.cw
+		// close.
+		select {
+		case err = <-ch:
+			frameWriteDone = true
+		default:
+			return http2errStreamClosed
+		}
+	}
+	http2errChanPool.Put(ch)
+	if frameWriteDone {
+		http2writeDataPool.Put(writeArg)
+	}
+	return err
+}
+
+// writeFrameFromHandler sends wr to sc.wantWriteFrameCh, but aborts
+// if the connection has gone away.
+//
+// This must not be run from the serve goroutine itself, else it might
+// deadlock writing to sc.wantWriteFrameCh (which is only mildly
+// buffered and is read by serve itself). If you're on the serve
+// goroutine, call writeFrame instead.
+func (sc *http2serverConn) writeFrameFromHandler(wr http2FrameWriteRequest) error {
+	sc.serveG.checkNotOn() // NOT
+	select {
+	case sc.wantWriteFrameCh <- wr:
+		return nil
+	case <-sc.doneServing:
+		// Serve loop is gone.
+		// Client has closed their connection to the server.
+		return http2errClientDisconnected
+	}
+}
+
+// writeFrame schedules a frame to write and sends it if there's nothing
+// already being written.
+//
+// There is no pushback here (the serve goroutine never blocks). It's
+// the http.Handlers that block, waiting for their previous frames to
+// make it onto the wire
+//
+// If you're not on the serve goroutine, use writeFrameFromHandler instead.
+func (sc *http2serverConn) writeFrame(wr http2FrameWriteRequest) {
+	sc.serveG.check()
+
+	// If true, wr will not be written and wr.done will not be signaled.
+	var ignoreWrite bool
+
+	// We are not allowed to write frames on closed streams. RFC 7540 Section
+	// 5.1.1 says: "An endpoint MUST NOT send frames other than PRIORITY on
+	// a closed stream." Our server never sends PRIORITY, so that exception
+	// does not apply.
+	//
+	// The serverConn might close an open stream while the stream's handler
+	// is still running. For example, the server might close a stream when it
+	// receives bad data from the client. If this happens, the handler might
+	// attempt to write a frame after the stream has been closed (since the
+	// handler hasn't yet been notified of the close). In this case, we simply
+	// ignore the frame. The handler will notice that the stream is closed when
+	// it waits for the frame to be written.
+	//
+	// As an exception to this rule, we allow sending RST_STREAM after close.
+	// This allows us to immediately reject new streams without tracking any
+	// state for those streams (except for the queued RST_STREAM frame). This
+	// may result in duplicate RST_STREAMs in some cases, but the client should
+	// ignore those.
+	if wr.StreamID() != 0 {
+		_, isReset := wr.write.(http2StreamError)
+		if state, _ := sc.state(wr.StreamID()); state == http2stateClosed && !isReset {
+			ignoreWrite = true
+		}
+	}
+
+	// Don't send a 100-continue response if we've already sent headers.
+	// See golang.org/issue/14030.
+	switch wr.write.(type) {
+	case *http2writeResHeaders:
+		wr.stream.wroteHeaders = true
+	case http2write100ContinueHeadersFrame:
+		if wr.stream.wroteHeaders {
+			// We do not need to notify wr.done because this frame is
+			// never written with wr.done != nil.
+			if wr.done != nil {
+				panic("wr.done != nil for write100ContinueHeadersFrame")
+			}
+			ignoreWrite = true
+		}
+	}
+
+	if !ignoreWrite {
+		if wr.isControl() {
+			sc.queuedControlFrames++
+			// For extra safety, detect wraparounds, which should not happen,
+			// and pull the plug.
+			if sc.queuedControlFrames < 0 {
+				sc.conn.Close()
+			}
+		}
+		sc.writeSched.Push(wr)
+	}
+	sc.scheduleFrameWrite()
+}
+
+// startFrameWrite starts a goroutine to write wr (in a separate
+// goroutine since that might block on the network), and updates the
+// serve goroutine's state about the world, updated from info in wr.
+func (sc *http2serverConn) startFrameWrite(wr http2FrameWriteRequest) {
+	sc.serveG.check()
+	if sc.writingFrame {
+		panic("internal error: can only be writing one frame at a time")
+	}
+
+	st := wr.stream
+	if st != nil {
+		switch st.state {
+		case http2stateHalfClosedLocal:
+			switch wr.write.(type) {
+			case http2StreamError, http2handlerPanicRST, http2writeWindowUpdate:
+				// RFC 7540 Section 5.1 allows sending RST_STREAM, PRIORITY, and WINDOW_UPDATE
+				// in this state. (We never send PRIORITY from the server, so that is not checked.)
+			default:
+				panic(fmt.Sprintf("internal error: attempt to send frame on a half-closed-local stream: %v", wr))
+			}
+		case http2stateClosed:
+			panic(fmt.Sprintf("internal error: attempt to send frame on a closed stream: %v", wr))
+		}
+	}
+	if wpp, ok := wr.write.(*http2writePushPromise); ok {
+		var err error
+		wpp.promisedID, err = wpp.allocatePromisedID()
+		if err != nil {
+			sc.writingFrameAsync = false
+			wr.replyToWriter(err)
+			return
+		}
+	}
+
+	sc.writingFrame = true
+	sc.needsFrameFlush = true
+	if wr.write.staysWithinBuffer(sc.bw.Available()) {
+		sc.writingFrameAsync = false
+		err := wr.write.writeFrame(sc)
+		sc.wroteFrame(http2frameWriteResult{wr: wr, err: err})
+	} else {
+		sc.writingFrameAsync = true
+		go sc.writeFrameAsync(wr)
+	}
+}
+
+// errHandlerPanicked is the error given to any callers blocked in a read from
+// Request.Body when the main goroutine panics. Since most handlers read in the
+// main ServeHTTP goroutine, this will show up rarely.
+var http2errHandlerPanicked = errors.New("http2: handler panicked")
+
+// wroteFrame is called on the serve goroutine with the result of
+// whatever happened on writeFrameAsync.
+func (sc *http2serverConn) wroteFrame(res http2frameWriteResult) {
+	sc.serveG.check()
+	if !sc.writingFrame {
+		panic("internal error: expected to be already writing a frame")
+	}
+	sc.writingFrame = false
+	sc.writingFrameAsync = false
+
+	wr := res.wr
+
+	if http2writeEndsStream(wr.write) {
+		st := wr.stream
+		if st == nil {
+			panic("internal error: expecting non-nil stream")
+		}
+		switch st.state {
+		case http2stateOpen:
+			// Here we would go to stateHalfClosedLocal in
+			// theory, but since our handler is done and
+			// the net/http package provides no mechanism
+			// for closing a ResponseWriter while still
+			// reading data (see possible TODO at top of
+			// this file), we go into closed state here
+			// anyway, after telling the peer we're
+			// hanging up on them. We'll transition to
+			// stateClosed after the RST_STREAM frame is
+			// written.
+			st.state = http2stateHalfClosedLocal
+			// Section 8.1: a server MAY request that the client abort
+			// transmission of a request without error by sending a
+			// RST_STREAM with an error code of NO_ERROR after sending
+			// a complete response.
+			sc.resetStream(http2streamError(st.id, http2ErrCodeNo))
+		case http2stateHalfClosedRemote:
+			sc.closeStream(st, http2errHandlerComplete)
+		}
+	} else {
+		switch v := wr.write.(type) {
+		case http2StreamError:
+			// st may be unknown if the RST_STREAM was generated to reject bad input.
+			if st, ok := sc.streams[v.StreamID]; ok {
+				sc.closeStream(st, v)
+			}
+		case http2handlerPanicRST:
+			sc.closeStream(wr.stream, http2errHandlerPanicked)
+		}
+	}
+
+	// Reply (if requested) to unblock the ServeHTTP goroutine.
+	wr.replyToWriter(res.err)
+
+	sc.scheduleFrameWrite()
+}
+
+// scheduleFrameWrite tickles the frame writing scheduler.
+//
+// If a frame is already being written, nothing happens. This will be called again
+// when the frame is done being written.
+//
+// If a frame isn't being written and we need to send one, the best frame
+// to send is selected by writeSched.
+//
+// If a frame isn't being written and there's nothing else to send, we
+// flush the write buffer.
+func (sc *http2serverConn) scheduleFrameWrite() {
+	sc.serveG.check()
+	if sc.writingFrame || sc.inFrameScheduleLoop {
+		return
+	}
+	sc.inFrameScheduleLoop = true
+	for !sc.writingFrameAsync {
+		if sc.needToSendGoAway {
+			sc.needToSendGoAway = false
+			sc.startFrameWrite(http2FrameWriteRequest{
+				write: &http2writeGoAway{
+					maxStreamID: sc.maxClientStreamID,
+					code:        sc.goAwayCode,
+				},
+			})
+			continue
+		}
+		if sc.needToSendSettingsAck {
+			sc.needToSendSettingsAck = false
+			sc.startFrameWrite(http2FrameWriteRequest{write: http2writeSettingsAck{}})
+			continue
+		}
+		if !sc.inGoAway || sc.goAwayCode == http2ErrCodeNo {
+			if wr, ok := sc.writeSched.Pop(); ok {
+				if wr.isControl() {
+					sc.queuedControlFrames--
+				}
+				sc.startFrameWrite(wr)
+				continue
+			}
+		}
+		if sc.needsFrameFlush {
+			sc.startFrameWrite(http2FrameWriteRequest{write: http2flushFrameWriter{}})
+			sc.needsFrameFlush = false // after startFrameWrite, since it sets this true
+			continue
+		}
+		break
+	}
+	sc.inFrameScheduleLoop = false
+}
+
+// startGracefulShutdown gracefully shuts down a connection. This
+// sends GOAWAY with ErrCodeNo to tell the client we're gracefully
+// shutting down. The connection isn't closed until all current
+// streams are done.
+//
+// startGracefulShutdown returns immediately; it does not wait until
+// the connection has shut down.
+func (sc *http2serverConn) startGracefulShutdown() {
+	sc.serveG.checkNotOn() // NOT
+	sc.shutdownOnce.Do(func() { sc.sendServeMsg(http2gracefulShutdownMsg) })
+}
+
+// After sending GOAWAY with an error code (non-graceful shutdown), the
+// connection will close after goAwayTimeout.
+//
+// If we close the connection immediately after sending GOAWAY, there may
+// be unsent data in our kernel receive buffer, which will cause the kernel
+// to send a TCP RST on close() instead of a FIN. This RST will abort the
+// connection immediately, whether or not the client had received the GOAWAY.
+//
+// Ideally we should delay for at least 1 RTT + epsilon so the client has
+// a chance to read the GOAWAY and stop sending messages. Measuring RTT
+// is hard, so we approximate with 1 second. See golang.org/issue/18701.
+//
+// This is a var so it can be shorter in tests, where all requests uses the
+// loopback interface making the expected RTT very small.
+//
+// TODO: configurable?
+var http2goAwayTimeout = 1 * time.Second
+
+func (sc *http2serverConn) startGracefulShutdownInternal() {
+	sc.goAway(http2ErrCodeNo)
+}
+
+func (sc *http2serverConn) goAway(code http2ErrCode) {
+	sc.serveG.check()
+	if sc.inGoAway {
+		if sc.goAwayCode == http2ErrCodeNo {
+			sc.goAwayCode = code
+		}
+		return
+	}
+	sc.inGoAway = true
+	sc.needToSendGoAway = true
+	sc.goAwayCode = code
+	sc.scheduleFrameWrite()
+}
+
+func (sc *http2serverConn) shutDownIn(d time.Duration) {
+	sc.serveG.check()
+	sc.shutdownTimer = time.AfterFunc(d, sc.onShutdownTimer)
+}
+
+func (sc *http2serverConn) resetStream(se http2StreamError) {
+	sc.serveG.check()
+	sc.writeFrame(http2FrameWriteRequest{write: se})
+	if st, ok := sc.streams[se.StreamID]; ok {
+		st.resetQueued = true
+	}
+}
+
+// processFrameFromReader processes the serve loop's read from readFrameCh from the
+// frame-reading goroutine.
+// processFrameFromReader returns whether the connection should be kept open.
+func (sc *http2serverConn) processFrameFromReader(res http2readFrameResult) bool {
+	sc.serveG.check()
+	err := res.err
+	if err != nil {
+		if err == http2ErrFrameTooLarge {
+			sc.goAway(http2ErrCodeFrameSize)
+			return true // goAway will close the loop
+		}
+		clientGone := err == io.EOF || err == io.ErrUnexpectedEOF || http2isClosedConnError(err)
+		if clientGone {
+			// TODO: could we also get into this state if
+			// the peer does a half close
+			// (e.g. CloseWrite) because they're done
+			// sending frames but they're still wanting
+			// our open replies?  Investigate.
+			// TODO: add CloseWrite to crypto/tls.Conn first
+			// so we have a way to test this? I suppose
+			// just for testing we could have a non-TLS mode.
+			return false
+		}
+	} else {
+		f := res.f
+		if http2VerboseLogs {
+			sc.vlogf("http2: server read frame %v", http2summarizeFrame(f))
+		}
+		err = sc.processFrame(f)
+		if err == nil {
+			return true
+		}
+	}
+
+	switch ev := err.(type) {
+	case http2StreamError:
+		sc.resetStream(ev)
+		return true
+	case http2goAwayFlowError:
+		sc.goAway(http2ErrCodeFlowControl)
+		return true
+	case http2ConnectionError:
+		sc.logf("http2: server connection error from %v: %v", sc.conn.RemoteAddr(), ev)
+		sc.goAway(http2ErrCode(ev))
+		return true // goAway will handle shutdown
+	default:
+		if res.err != nil {
+			sc.vlogf("http2: server closing client connection; error reading frame from client %s: %v", sc.conn.RemoteAddr(), err)
+		} else {
+			sc.logf("http2: server closing client connection: %v", err)
+		}
+		return false
+	}
+}
+
+func (sc *http2serverConn) processFrame(f http2Frame) error {
+	sc.serveG.check()
+
+	// First frame received must be SETTINGS.
+	if !sc.sawFirstSettings {
+		if _, ok := f.(*http2SettingsFrame); !ok {
+			return sc.countError("first_settings", http2ConnectionError(http2ErrCodeProtocol))
+		}
+		sc.sawFirstSettings = true
+	}
+
+	switch f := f.(type) {
+	case *http2SettingsFrame:
+		return sc.processSettings(f)
+	case *http2MetaHeadersFrame:
+		return sc.processHeaders(f)
+	case *http2WindowUpdateFrame:
+		return sc.processWindowUpdate(f)
+	case *http2PingFrame:
+		return sc.processPing(f)
+	case *http2DataFrame:
+		return sc.processData(f)
+	case *http2RSTStreamFrame:
+		return sc.processResetStream(f)
+	case *http2PriorityFrame:
+		return sc.processPriority(f)
+	case *http2GoAwayFrame:
+		return sc.processGoAway(f)
+	case *http2PushPromiseFrame:
+		// A client cannot push. Thus, servers MUST treat the receipt of a PUSH_PROMISE
+		// frame as a connection error (Section 5.4.1) of type PROTOCOL_ERROR.
+		return sc.countError("push_promise", http2ConnectionError(http2ErrCodeProtocol))
+	default:
+		sc.vlogf("http2: server ignoring frame: %v", f.Header())
+		return nil
+	}
+}
+
+func (sc *http2serverConn) processPing(f *http2PingFrame) error {
+	sc.serveG.check()
+	if f.IsAck() {
+		// 6.7 PING: " An endpoint MUST NOT respond to PING frames
+		// containing this flag."
+		return nil
+	}
+	if f.StreamID != 0 {
+		// "PING frames are not associated with any individual
+		// stream. If a PING frame is received with a stream
+		// identifier field value other than 0x0, the recipient MUST
+		// respond with a connection error (Section 5.4.1) of type
+		// PROTOCOL_ERROR."
+		return sc.countError("ping_on_stream", http2ConnectionError(http2ErrCodeProtocol))
+	}
+	if sc.inGoAway && sc.goAwayCode != http2ErrCodeNo {
+		return nil
+	}
+	sc.writeFrame(http2FrameWriteRequest{write: http2writePingAck{f}})
+	return nil
+}
+
+func (sc *http2serverConn) processWindowUpdate(f *http2WindowUpdateFrame) error {
+	sc.serveG.check()
+	switch {
+	case f.StreamID != 0: // stream-level flow control
+		state, st := sc.state(f.StreamID)
+		if state == http2stateIdle {
+			// Section 5.1: "Receiving any frame other than HEADERS
+			// or PRIORITY on a stream in this state MUST be
+			// treated as a connection error (Section 5.4.1) of
+			// type PROTOCOL_ERROR."
+			return sc.countError("stream_idle", http2ConnectionError(http2ErrCodeProtocol))
+		}
+		if st == nil {
+			// "WINDOW_UPDATE can be sent by a peer that has sent a
+			// frame bearing the END_STREAM flag. This means that a
+			// receiver could receive a WINDOW_UPDATE frame on a "half
+			// closed (remote)" or "closed" stream. A receiver MUST
+			// NOT treat this as an error, see Section 5.1."
+			return nil
+		}
+		if !st.flow.add(int32(f.Increment)) {
+			return sc.countError("bad_flow", http2streamError(f.StreamID, http2ErrCodeFlowControl))
+		}
+	default: // connection-level flow control
+		if !sc.flow.add(int32(f.Increment)) {
+			return http2goAwayFlowError{}
+		}
+	}
+	sc.scheduleFrameWrite()
+	return nil
+}
+
+func (sc *http2serverConn) processResetStream(f *http2RSTStreamFrame) error {
+	sc.serveG.check()
+
+	state, st := sc.state(f.StreamID)
+	if state == http2stateIdle {
+		// 6.4 "RST_STREAM frames MUST NOT be sent for a
+		// stream in the "idle" state. If a RST_STREAM frame
+		// identifying an idle stream is received, the
+		// recipient MUST treat this as a connection error
+		// (Section 5.4.1) of type PROTOCOL_ERROR.
+		return sc.countError("reset_idle_stream", http2ConnectionError(http2ErrCodeProtocol))
+	}
+	if st != nil {
+		st.cancelCtx()
+		sc.closeStream(st, http2streamError(f.StreamID, f.ErrCode))
+	}
+	return nil
+}
+
+func (sc *http2serverConn) closeStream(st *http2stream, err error) {
+	sc.serveG.check()
+	if st.state == http2stateIdle || st.state == http2stateClosed {
+		panic(fmt.Sprintf("invariant; can't close stream in state %v", st.state))
+	}
+	st.state = http2stateClosed
+	if st.writeDeadline != nil {
+		st.writeDeadline.Stop()
+	}
+	if st.isPushed() {
+		sc.curPushedStreams--
+	} else {
+		sc.curClientStreams--
+	}
+	delete(sc.streams, st.id)
+	if len(sc.streams) == 0 {
+		sc.setConnState(StateIdle)
+		if sc.srv.IdleTimeout != 0 {
+			sc.idleTimer.Reset(sc.srv.IdleTimeout)
+		}
+		if http2h1ServerKeepAlivesDisabled(sc.hs) {
+			sc.startGracefulShutdownInternal()
+		}
+	}
+	if p := st.body; p != nil {
+		// Return any buffered unread bytes worth of conn-level flow control.
+		// See golang.org/issue/16481
+		sc.sendWindowUpdate(nil, p.Len())
+
+		p.CloseWithError(err)
+	}
+	st.cw.Close() // signals Handler's CloseNotifier, unblocks writes, etc
+	sc.writeSched.CloseStream(st.id)
+}
+
+func (sc *http2serverConn) processSettings(f *http2SettingsFrame) error {
+	sc.serveG.check()
+	if f.IsAck() {
+		sc.unackedSettings--
+		if sc.unackedSettings < 0 {
+			// Why is the peer ACKing settings we never sent?
+			// The spec doesn't mention this case, but
+			// hang up on them anyway.
+			return sc.countError("ack_mystery", http2ConnectionError(http2ErrCodeProtocol))
+		}
+		return nil
+	}
+	if f.NumSettings() > 100 || f.HasDuplicates() {
+		// This isn't actually in the spec, but hang up on
+		// suspiciously large settings frames or those with
+		// duplicate entries.
+		return sc.countError("settings_big_or_dups", http2ConnectionError(http2ErrCodeProtocol))
+	}
+	if err := f.ForeachSetting(sc.processSetting); err != nil {
+		return err
+	}
+	// TODO: judging by RFC 7540, Section 6.5.3 each SETTINGS frame should be
+	// acknowledged individually, even if multiple are received before the ACK.
+	sc.needToSendSettingsAck = true
+	sc.scheduleFrameWrite()
+	return nil
+}
+
+func (sc *http2serverConn) processSetting(s http2Setting) error {
+	sc.serveG.check()
+	if err := s.Valid(); err != nil {
+		return err
+	}
+	if http2VerboseLogs {
+		sc.vlogf("http2: server processing setting %v", s)
+	}
+	switch s.ID {
+	case http2SettingHeaderTableSize:
+		sc.headerTableSize = s.Val
+		sc.hpackEncoder.SetMaxDynamicTableSize(s.Val)
+	case http2SettingEnablePush:
+		sc.pushEnabled = s.Val != 0
+	case http2SettingMaxConcurrentStreams:
+		sc.clientMaxStreams = s.Val
+	case http2SettingInitialWindowSize:
+		return sc.processSettingInitialWindowSize(s.Val)
+	case http2SettingMaxFrameSize:
+		sc.maxFrameSize = int32(s.Val) // the maximum valid s.Val is < 2^31
+	case http2SettingMaxHeaderListSize:
+		sc.peerMaxHeaderListSize = s.Val
+	default:
+		// Unknown setting: "An endpoint that receives a SETTINGS
+		// frame with any unknown or unsupported identifier MUST
+		// ignore that setting."
+		if http2VerboseLogs {
+			sc.vlogf("http2: server ignoring unknown setting %v", s)
+		}
+	}
+	return nil
+}
+
+func (sc *http2serverConn) processSettingInitialWindowSize(val uint32) error {
+	sc.serveG.check()
+	// Note: val already validated to be within range by
+	// processSetting's Valid call.
+
+	// "A SETTINGS frame can alter the initial flow control window
+	// size for all current streams. When the value of
+	// SETTINGS_INITIAL_WINDOW_SIZE changes, a receiver MUST
+	// adjust the size of all stream flow control windows that it
+	// maintains by the difference between the new value and the
+	// old value."
+	old := sc.initialStreamSendWindowSize
+	sc.initialStreamSendWindowSize = int32(val)
+	growth := int32(val) - old // may be negative
+	for _, st := range sc.streams {
+		if !st.flow.add(growth) {
+			// 6.9.2 Initial Flow Control Window Size
+			// "An endpoint MUST treat a change to
+			// SETTINGS_INITIAL_WINDOW_SIZE that causes any flow
+			// control window to exceed the maximum size as a
+			// connection error (Section 5.4.1) of type
+			// FLOW_CONTROL_ERROR."
+			return sc.countError("setting_win_size", http2ConnectionError(http2ErrCodeFlowControl))
+		}
+	}
+	return nil
+}
+
+func (sc *http2serverConn) processData(f *http2DataFrame) error {
+	sc.serveG.check()
+	id := f.Header().StreamID
+	if sc.inGoAway && (sc.goAwayCode != http2ErrCodeNo || id > sc.maxClientStreamID) {
+		// Discard all DATA frames if the GOAWAY is due to an
+		// error, or:
+		//
+		// Section 6.8: After sending a GOAWAY frame, the sender
+		// can discard frames for streams initiated by the
+		// receiver with identifiers higher than the identified
+		// last stream.
+		return nil
+	}
+
+	data := f.Data()
+	state, st := sc.state(id)
+	if id == 0 || state == http2stateIdle {
+		// Section 6.1: "DATA frames MUST be associated with a
+		// stream. If a DATA frame is received whose stream
+		// identifier field is 0x0, the recipient MUST respond
+		// with a connection error (Section 5.4.1) of type
+		// PROTOCOL_ERROR."
+		//
+		// Section 5.1: "Receiving any frame other than HEADERS
+		// or PRIORITY on a stream in this state MUST be
+		// treated as a connection error (Section 5.4.1) of
+		// type PROTOCOL_ERROR."
+		return sc.countError("data_on_idle", http2ConnectionError(http2ErrCodeProtocol))
+	}
+
+	// "If a DATA frame is received whose stream is not in "open"
+	// or "half closed (local)" state, the recipient MUST respond
+	// with a stream error (Section 5.4.2) of type STREAM_CLOSED."
+	if st == nil || state != http2stateOpen || st.gotTrailerHeader || st.resetQueued {
+		// This includes sending a RST_STREAM if the stream is
+		// in stateHalfClosedLocal (which currently means that
+		// the http.Handler returned, so it's done reading &
+		// done writing). Try to stop the client from sending
+		// more DATA.
+
+		// But still enforce their connection-level flow control,
+		// and return any flow control bytes since we're not going
+		// to consume them.
+		if sc.inflow.available() < int32(f.Length) {
+			return sc.countError("data_flow", http2streamError(id, http2ErrCodeFlowControl))
+		}
+		// Deduct the flow control from inflow, since we're
+		// going to immediately add it back in
+		// sendWindowUpdate, which also schedules sending the
+		// frames.
+		sc.inflow.take(int32(f.Length))
+		sc.sendWindowUpdate(nil, int(f.Length)) // conn-level
+
+		if st != nil && st.resetQueued {
+			// Already have a stream error in flight. Don't send another.
+			return nil
+		}
+		return sc.countError("closed", http2streamError(id, http2ErrCodeStreamClosed))
+	}
+	if st.body == nil {
+		panic("internal error: should have a body in this state")
+	}
+
+	// Sender sending more than they'd declared?
+	if st.declBodyBytes != -1 && st.bodyBytes+int64(len(data)) > st.declBodyBytes {
+		st.body.CloseWithError(fmt.Errorf("sender tried to send more than declared Content-Length of %d bytes", st.declBodyBytes))
+		// RFC 7540, sec 8.1.2.6: A request or response is also malformed if the
+		// value of a content-length header field does not equal the sum of the
+		// DATA frame payload lengths that form the body.
+		return sc.countError("send_too_much", http2streamError(id, http2ErrCodeProtocol))
+	}
+	if f.Length > 0 {
+		// Check whether the client has flow control quota.
+		if st.inflow.available() < int32(f.Length) {
+			return sc.countError("flow_on_data_length", http2streamError(id, http2ErrCodeFlowControl))
+		}
+		st.inflow.take(int32(f.Length))
+
+		if len(data) > 0 {
+			wrote, err := st.body.Write(data)
+			if err != nil {
+				sc.sendWindowUpdate(nil, int(f.Length)-wrote)
+				return sc.countError("body_write_err", http2streamError(id, http2ErrCodeStreamClosed))
+			}
+			if wrote != len(data) {
+				panic("internal error: bad Writer")
+			}
+			st.bodyBytes += int64(len(data))
+		}
+
+		// Return any padded flow control now, since we won't
+		// refund it later on body reads.
+		if pad := int32(f.Length) - int32(len(data)); pad > 0 {
+			sc.sendWindowUpdate32(nil, pad)
+			sc.sendWindowUpdate32(st, pad)
+		}
+	}
+	if f.StreamEnded() {
+		st.endStream()
+	}
+	return nil
+}
+
+func (sc *http2serverConn) processGoAway(f *http2GoAwayFrame) error {
+	sc.serveG.check()
+	if f.ErrCode != http2ErrCodeNo {
+		sc.logf("http2: received GOAWAY %+v, starting graceful shutdown", f)
+	} else {
+		sc.vlogf("http2: received GOAWAY %+v, starting graceful shutdown", f)
+	}
+	sc.startGracefulShutdownInternal()
+	// http://tools.ietf.org/html/rfc7540#section-6.8
+	// We should not create any new streams, which means we should disable push.
+	sc.pushEnabled = false
+	return nil
+}
+
+// isPushed reports whether the stream is server-initiated.
+func (st *http2stream) isPushed() bool {
+	return st.id%2 == 0
+}
+
+// endStream closes a Request.Body's pipe. It is called when a DATA
+// frame says a request body is over (or after trailers).
+func (st *http2stream) endStream() {
+	sc := st.sc
+	sc.serveG.check()
+
+	if st.declBodyBytes != -1 && st.declBodyBytes != st.bodyBytes {
+		st.body.CloseWithError(fmt.Errorf("request declared a Content-Length of %d but only wrote %d bytes",
+			st.declBodyBytes, st.bodyBytes))
+	} else {
+		st.body.closeWithErrorAndCode(io.EOF, st.copyTrailersToHandlerRequest)
+		st.body.CloseWithError(io.EOF)
+	}
+	st.state = http2stateHalfClosedRemote
+}
+
+// copyTrailersToHandlerRequest is run in the Handler's goroutine in
+// its Request.Body.Read just before it gets io.EOF.
+func (st *http2stream) copyTrailersToHandlerRequest() {
+	for k, vv := range st.trailer {
+		if _, ok := st.reqTrailer[k]; ok {
+			// Only copy it over it was pre-declared.
+			st.reqTrailer[k] = vv
+		}
+	}
+}
+
+// onWriteTimeout is run on its own goroutine (from time.AfterFunc)
+// when the stream's WriteTimeout has fired.
+func (st *http2stream) onWriteTimeout() {
+	st.sc.writeFrameFromHandler(http2FrameWriteRequest{write: http2streamError(st.id, http2ErrCodeInternal)})
+}
+
+func (sc *http2serverConn) processHeaders(f *http2MetaHeadersFrame) error {
+	sc.serveG.check()
+	id := f.StreamID
+	if sc.inGoAway {
+		// Ignore.
+		return nil
+	}
+	// http://tools.ietf.org/html/rfc7540#section-5.1.1
+	// Streams initiated by a client MUST use odd-numbered stream
+	// identifiers. [...] An endpoint that receives an unexpected
+	// stream identifier MUST respond with a connection error
+	// (Section 5.4.1) of type PROTOCOL_ERROR.
+	if id%2 != 1 {
+		return sc.countError("headers_even", http2ConnectionError(http2ErrCodeProtocol))
+	}
+	// A HEADERS frame can be used to create a new stream or
+	// send a trailer for an open one. If we already have a stream
+	// open, let it process its own HEADERS frame (trailers at this
+	// point, if it's valid).
+	if st := sc.streams[f.StreamID]; st != nil {
+		if st.resetQueued {
+			// We're sending RST_STREAM to close the stream, so don't bother
+			// processing this frame.
+			return nil
+		}
+		// RFC 7540, sec 5.1: If an endpoint receives additional frames, other than
+		// WINDOW_UPDATE, PRIORITY, or RST_STREAM, for a stream that is in
+		// this state, it MUST respond with a stream error (Section 5.4.2) of
+		// type STREAM_CLOSED.
+		if st.state == http2stateHalfClosedRemote {
+			return sc.countError("headers_half_closed", http2streamError(id, http2ErrCodeStreamClosed))
+		}
+		return st.processTrailerHeaders(f)
+	}
+
+	// [...] The identifier of a newly established stream MUST be
+	// numerically greater than all streams that the initiating
+	// endpoint has opened or reserved. [...]  An endpoint that
+	// receives an unexpected stream identifier MUST respond with
+	// a connection error (Section 5.4.1) of type PROTOCOL_ERROR.
+	if id <= sc.maxClientStreamID {
+		return sc.countError("stream_went_down", http2ConnectionError(http2ErrCodeProtocol))
+	}
+	sc.maxClientStreamID = id
+
+	if sc.idleTimer != nil {
+		sc.idleTimer.Stop()
+	}
+
+	// http://tools.ietf.org/html/rfc7540#section-5.1.2
+	// [...] Endpoints MUST NOT exceed the limit set by their peer. An
+	// endpoint that receives a HEADERS frame that causes their
+	// advertised concurrent stream limit to be exceeded MUST treat
+	// this as a stream error (Section 5.4.2) of type PROTOCOL_ERROR
+	// or REFUSED_STREAM.
+	if sc.curClientStreams+1 > sc.advMaxStreams {
+		if sc.unackedSettings == 0 {
+			// They should know better.
+			return sc.countError("over_max_streams", http2streamError(id, http2ErrCodeProtocol))
+		}
+		// Assume it's a network race, where they just haven't
+		// received our last SETTINGS update. But actually
+		// this can't happen yet, because we don't yet provide
+		// a way for users to adjust server parameters at
+		// runtime.
+		return sc.countError("over_max_streams_race", http2streamError(id, http2ErrCodeRefusedStream))
+	}
+
+	initialState := http2stateOpen
+	if f.StreamEnded() {
+		initialState = http2stateHalfClosedRemote
+	}
+	st := sc.newStream(id, 0, initialState)
+
+	if f.HasPriority() {
+		if err := sc.checkPriority(f.StreamID, f.Priority); err != nil {
+			return err
+		}
+		sc.writeSched.AdjustStream(st.id, f.Priority)
+	}
+
+	rw, req, err := sc.newWriterAndRequest(st, f)
+	if err != nil {
+		return err
+	}
+	st.reqTrailer = req.Trailer
+	if st.reqTrailer != nil {
+		st.trailer = make(Header)
+	}
+	st.body = req.Body.(*http2requestBody).pipe // may be nil
+	st.declBodyBytes = req.ContentLength
+
+	handler := sc.handler.ServeHTTP
+	if f.Truncated {
+		// Their header list was too long. Send a 431 error.
+		handler = http2handleHeaderListTooLong
+	} else if err := http2checkValidHTTP2RequestHeaders(req.Header); err != nil {
+		handler = http2new400Handler(err)
+	}
+
+	// The net/http package sets the read deadline from the
+	// http.Server.ReadTimeout during the TLS handshake, but then
+	// passes the connection off to us with the deadline already
+	// set. Disarm it here after the request headers are read,
+	// similar to how the http1 server works. Here it's
+	// technically more like the http1 Server's ReadHeaderTimeout
+	// (in Go 1.8), though. That's a more sane option anyway.
+	if sc.hs.ReadTimeout != 0 {
+		sc.conn.SetReadDeadline(time.Time{})
+	}
+
+	go sc.runHandler(rw, req, handler)
+	return nil
+}
+
+func (st *http2stream) processTrailerHeaders(f *http2MetaHeadersFrame) error {
+	sc := st.sc
+	sc.serveG.check()
+	if st.gotTrailerHeader {
+		return sc.countError("dup_trailers", http2ConnectionError(http2ErrCodeProtocol))
+	}
+	st.gotTrailerHeader = true
+	if !f.StreamEnded() {
+		return sc.countError("trailers_not_ended", http2streamError(st.id, http2ErrCodeProtocol))
+	}
+
+	if len(f.PseudoFields()) > 0 {
+		return sc.countError("trailers_pseudo", http2streamError(st.id, http2ErrCodeProtocol))
+	}
+	if st.trailer != nil {
+		for _, hf := range f.RegularFields() {
+			key := sc.canonicalHeader(hf.Name)
+			if !httpguts.ValidTrailerHeader(key) {
+				// TODO: send more details to the peer somehow. But http2 has
+				// no way to send debug data at a stream level. Discuss with
+				// HTTP folk.
+				return sc.countError("trailers_bogus", http2streamError(st.id, http2ErrCodeProtocol))
+			}
+			st.trailer[key] = append(st.trailer[key], hf.Value)
+		}
+	}
+	st.endStream()
+	return nil
+}
+
+func (sc *http2serverConn) checkPriority(streamID uint32, p http2PriorityParam) error {
+	if streamID == p.StreamDep {
+		// Section 5.3.1: "A stream cannot depend on itself. An endpoint MUST treat
+		// this as a stream error (Section 5.4.2) of type PROTOCOL_ERROR."
+		// Section 5.3.3 says that a stream can depend on one of its dependencies,
+		// so it's only self-dependencies that are forbidden.
+		return sc.countError("priority", http2streamError(streamID, http2ErrCodeProtocol))
+	}
+	return nil
+}
+
+func (sc *http2serverConn) processPriority(f *http2PriorityFrame) error {
+	if sc.inGoAway {
+		return nil
+	}
+	if err := sc.checkPriority(f.StreamID, f.http2PriorityParam); err != nil {
+		return err
+	}
+	sc.writeSched.AdjustStream(f.StreamID, f.http2PriorityParam)
+	return nil
+}
+
+func (sc *http2serverConn) newStream(id, pusherID uint32, state http2streamState) *http2stream {
+	sc.serveG.check()
+	if id == 0 {
+		panic("internal error: cannot create stream with id 0")
+	}
+
+	ctx, cancelCtx := context.WithCancel(sc.baseCtx)
+	st := &http2stream{
+		sc:        sc,
+		id:        id,
+		state:     state,
+		ctx:       ctx,
+		cancelCtx: cancelCtx,
+	}
+	st.cw.Init()
+	st.flow.conn = &sc.flow // link to conn-level counter
+	st.flow.add(sc.initialStreamSendWindowSize)
+	st.inflow.conn = &sc.inflow // link to conn-level counter
+	st.inflow.add(sc.srv.initialStreamRecvWindowSize())
+	if sc.hs.WriteTimeout != 0 {
+		st.writeDeadline = time.AfterFunc(sc.hs.WriteTimeout, st.onWriteTimeout)
+	}
+
+	sc.streams[id] = st
+	sc.writeSched.OpenStream(st.id, http2OpenStreamOptions{PusherID: pusherID})
+	if st.isPushed() {
+		sc.curPushedStreams++
+	} else {
+		sc.curClientStreams++
+	}
+	if sc.curOpenStreams() == 1 {
+		sc.setConnState(StateActive)
+	}
+
+	return st
+}
+
+func (sc *http2serverConn) newWriterAndRequest(st *http2stream, f *http2MetaHeadersFrame) (*http2responseWriter, *Request, error) {
+	sc.serveG.check()
+
+	rp := http2requestParam{
+		method:    f.PseudoValue("method"),
+		scheme:    f.PseudoValue("scheme"),
+		authority: f.PseudoValue("authority"),
+		path:      f.PseudoValue("path"),
+	}
+
+	isConnect := rp.method == "CONNECT"
+	if isConnect {
+		if rp.path != "" || rp.scheme != "" || rp.authority == "" {
+			return nil, nil, sc.countError("bad_connect", http2streamError(f.StreamID, http2ErrCodeProtocol))
+		}
+	} else if rp.method == "" || rp.path == "" || (rp.scheme != "https" && rp.scheme != "http") {
+		// See 8.1.2.6 Malformed Requests and Responses:
+		//
+		// Malformed requests or responses that are detected
+		// MUST be treated as a stream error (Section 5.4.2)
+		// of type PROTOCOL_ERROR."
+		//
+		// 8.1.2.3 Request Pseudo-Header Fields
+		// "All HTTP/2 requests MUST include exactly one valid
+		// value for the :method, :scheme, and :path
+		// pseudo-header fields"
+		return nil, nil, sc.countError("bad_path_method", http2streamError(f.StreamID, http2ErrCodeProtocol))
+	}
+
+	bodyOpen := !f.StreamEnded()
+	if rp.method == "HEAD" && bodyOpen {
+		// HEAD requests can't have bodies
+		return nil, nil, sc.countError("head_body", http2streamError(f.StreamID, http2ErrCodeProtocol))
+	}
+
+	rp.header = make(Header)
+	for _, hf := range f.RegularFields() {
+		rp.header.Add(sc.canonicalHeader(hf.Name), hf.Value)
+	}
+	if rp.authority == "" {
+		rp.authority = rp.header.Get("Host")
+	}
+
+	rw, req, err := sc.newWriterAndRequestNoBody(st, rp)
+	if err != nil {
+		return nil, nil, err
+	}
+	if bodyOpen {
+		if vv, ok := rp.header["Content-Length"]; ok {
+			if cl, err := strconv.ParseUint(vv[0], 10, 63); err == nil {
+				req.ContentLength = int64(cl)
+			} else {
+				req.ContentLength = 0
+			}
+		} else {
+			req.ContentLength = -1
+		}
+		req.Body.(*http2requestBody).pipe = &http2pipe{
+			b: &http2dataBuffer{expected: req.ContentLength},
+		}
+	}
+	return rw, req, nil
+}
+
+type http2requestParam struct {
+	method                  string
+	scheme, authority, path string
+	header                  Header
+}
+
+func (sc *http2serverConn) newWriterAndRequestNoBody(st *http2stream, rp http2requestParam) (*http2responseWriter, *Request, error) {
+	sc.serveG.check()
+
+	var tlsState *tls.ConnectionState // nil if not scheme https
+	if rp.scheme == "https" {
+		tlsState = sc.tlsState
+	}
+
+	needsContinue := rp.header.Get("Expect") == "100-continue"
+	if needsContinue {
+		rp.header.Del("Expect")
+	}
+	// Merge Cookie headers into one "; "-delimited value.
+	if cookies := rp.header["Cookie"]; len(cookies) > 1 {
+		rp.header.Set("Cookie", strings.Join(cookies, "; "))
+	}
+
+	// Setup Trailers
+	var trailer Header
+	for _, v := range rp.header["Trailer"] {
+		for _, key := range strings.Split(v, ",") {
+			key = CanonicalHeaderKey(textproto.TrimString(key))
+			switch key {
+			case "Transfer-Encoding", "Trailer", "Content-Length":
+				// Bogus. (copy of http1 rules)
+				// Ignore.
+			default:
+				if trailer == nil {
+					trailer = make(Header)
+				}
+				trailer[key] = nil
+			}
+		}
+	}
+	delete(rp.header, "Trailer")
+
+	var url_ *url.URL
+	var requestURI string
+	if rp.method == "CONNECT" {
+		url_ = &url.URL{Host: rp.authority}
+		requestURI = rp.authority // mimic HTTP/1 server behavior
+	} else {
+		var err error
+		url_, err = url.ParseRequestURI(rp.path)
+		if err != nil {
+			return nil, nil, sc.countError("bad_path", http2streamError(st.id, http2ErrCodeProtocol))
+		}
+		requestURI = rp.path
+	}
+
+	body := &http2requestBody{
+		conn:          sc,
+		stream:        st,
+		needsContinue: needsContinue,
+	}
+	req := &Request{
+		Method:     rp.method,
+		URL:        url_,
+		RemoteAddr: sc.remoteAddrStr,
+		Header:     rp.header,
+		RequestURI: requestURI,
+		Proto:      "HTTP/2.0",
+		ProtoMajor: 2,
+		ProtoMinor: 0,
+		TLS:        tlsState,
+		Host:       rp.authority,
+		Body:       body,
+		Trailer:    trailer,
+	}
+	req = req.WithContext(st.ctx)
+
+	rws := http2responseWriterStatePool.Get().(*http2responseWriterState)
+	bwSave := rws.bw
+	*rws = http2responseWriterState{} // zero all the fields
+	rws.conn = sc
+	rws.bw = bwSave
+	rws.bw.Reset(http2chunkWriter{rws})
+	rws.stream = st
+	rws.req = req
+	rws.body = body
+
+	rw := &http2responseWriter{rws: rws}
+	return rw, req, nil
+}
+
+// Run on its own goroutine.
+func (sc *http2serverConn) runHandler(rw *http2responseWriter, req *Request, handler func(ResponseWriter, *Request)) {
+	didPanic := true
+	defer func() {
+		rw.rws.stream.cancelCtx()
+		if didPanic {
+			e := recover()
+			sc.writeFrameFromHandler(http2FrameWriteRequest{
+				write:  http2handlerPanicRST{rw.rws.stream.id},
+				stream: rw.rws.stream,
+			})
+			// Same as net/http:
+			if e != nil && e != ErrAbortHandler {
+				const size = 64 << 10
+				buf := make([]byte, size)
+				buf = buf[:runtime.Stack(buf, false)]
+				sc.logf("http2: panic serving %v: %v\n%s", sc.conn.RemoteAddr(), e, buf)
+			}
+			return
+		}
+		rw.handlerDone()
+	}()
+	handler(rw, req)
+	didPanic = false
+}
+
+func http2handleHeaderListTooLong(w ResponseWriter, r *Request) {
+	// 10.5.1 Limits on Header Block Size:
+	// .. "A server that receives a larger header block than it is
+	// willing to handle can send an HTTP 431 (Request Header Fields Too
+	// Large) status code"
+	const statusRequestHeaderFieldsTooLarge = 431 // only in Go 1.6+
+	w.WriteHeader(statusRequestHeaderFieldsTooLarge)
+	io.WriteString(w, "<h1>HTTP Error 431</h1><p>Request Header Field(s) Too Large</p>")
+}
+
+// called from handler goroutines.
+// h may be nil.
+func (sc *http2serverConn) writeHeaders(st *http2stream, headerData *http2writeResHeaders) error {
+	sc.serveG.checkNotOn() // NOT on
+	var errc chan error
+	if headerData.h != nil {
+		// If there's a header map (which we don't own), so we have to block on
+		// waiting for this frame to be written, so an http.Flush mid-handler
+		// writes out the correct value of keys, before a handler later potentially
+		// mutates it.
+		errc = http2errChanPool.Get().(chan error)
+	}
+	if err := sc.writeFrameFromHandler(http2FrameWriteRequest{
+		write:  headerData,
+		stream: st,
+		done:   errc,
+	}); err != nil {
+		return err
+	}
+	if errc != nil {
+		select {
+		case err := <-errc:
+			http2errChanPool.Put(errc)
+			return err
+		case <-sc.doneServing:
+			return http2errClientDisconnected
+		case <-st.cw:
+			return http2errStreamClosed
+		}
+	}
+	return nil
+}
+
+// called from handler goroutines.
+func (sc *http2serverConn) write100ContinueHeaders(st *http2stream) {
+	sc.writeFrameFromHandler(http2FrameWriteRequest{
+		write:  http2write100ContinueHeadersFrame{st.id},
+		stream: st,
+	})
+}
+
+// A bodyReadMsg tells the server loop that the http.Handler read n
+// bytes of the DATA from the client on the given stream.
+type http2bodyReadMsg struct {
+	st *http2stream
+	n  int
+}
+
+// called from handler goroutines.
+// Notes that the handler for the given stream ID read n bytes of its body
+// and schedules flow control tokens to be sent.
+func (sc *http2serverConn) noteBodyReadFromHandler(st *http2stream, n int, err error) {
+	sc.serveG.checkNotOn() // NOT on
+	if n > 0 {
+		select {
+		case sc.bodyReadCh <- http2bodyReadMsg{st, n}:
+		case <-sc.doneServing:
+		}
+	}
+}
+
+func (sc *http2serverConn) noteBodyRead(st *http2stream, n int) {
+	sc.serveG.check()
+	sc.sendWindowUpdate(nil, n) // conn-level
+	if st.state != http2stateHalfClosedRemote && st.state != http2stateClosed {
+		// Don't send this WINDOW_UPDATE if the stream is closed
+		// remotely.
+		sc.sendWindowUpdate(st, n)
+	}
+}
+
+// st may be nil for conn-level
+func (sc *http2serverConn) sendWindowUpdate(st *http2stream, n int) {
+	sc.serveG.check()
+	// "The legal range for the increment to the flow control
+	// window is 1 to 2^31-1 (2,147,483,647) octets."
+	// A Go Read call on 64-bit machines could in theory read
+	// a larger Read than this. Very unlikely, but we handle it here
+	// rather than elsewhere for now.
+	const maxUint31 = 1<<31 - 1
+	for n >= maxUint31 {
+		sc.sendWindowUpdate32(st, maxUint31)
+		n -= maxUint31
+	}
+	sc.sendWindowUpdate32(st, int32(n))
+}
+
+// st may be nil for conn-level
+func (sc *http2serverConn) sendWindowUpdate32(st *http2stream, n int32) {
+	sc.serveG.check()
+	if n == 0 {
+		return
+	}
+	if n < 0 {
+		panic("negative update")
+	}
+	var streamID uint32
+	if st != nil {
+		streamID = st.id
+	}
+	sc.writeFrame(http2FrameWriteRequest{
+		write:  http2writeWindowUpdate{streamID: streamID, n: uint32(n)},
+		stream: st,
+	})
+	var ok bool
+	if st == nil {
+		ok = sc.inflow.add(n)
+	} else {
+		ok = st.inflow.add(n)
+	}
+	if !ok {
+		panic("internal error; sent too many window updates without decrements?")
+	}
+}
+
+// requestBody is the Handler's Request.Body type.
+// Read and Close may be called concurrently.
+type http2requestBody struct {
+	_             http2incomparable
+	stream        *http2stream
+	conn          *http2serverConn
+	closeOnce     sync.Once  // for use by Close only
+	sawEOF        bool       // for use by Read only
+	pipe          *http2pipe // non-nil if we have a HTTP entity message body
+	needsContinue bool       // need to send a 100-continue
+}
+
+func (b *http2requestBody) Close() error {
+	b.closeOnce.Do(func() {
+		if b.pipe != nil {
+			b.pipe.BreakWithError(http2errClosedBody)
+		}
+	})
+	return nil
+}
+
+func (b *http2requestBody) Read(p []byte) (n int, err error) {
+	if b.needsContinue {
+		b.needsContinue = false
+		b.conn.write100ContinueHeaders(b.stream)
+	}
+	if b.pipe == nil || b.sawEOF {
+		return 0, io.EOF
+	}
+	n, err = b.pipe.Read(p)
+	if err == io.EOF {
+		b.sawEOF = true
+	}
+	if b.conn == nil && http2inTests {
+		return
+	}
+	b.conn.noteBodyReadFromHandler(b.stream, n, err)
+	return
+}
+
+// responseWriter is the http.ResponseWriter implementation. It's
+// intentionally small (1 pointer wide) to minimize garbage. The
+// responseWriterState pointer inside is zeroed at the end of a
+// request (in handlerDone) and calls on the responseWriter thereafter
+// simply crash (caller's mistake), but the much larger responseWriterState
+// and buffers are reused between multiple requests.
+type http2responseWriter struct {
+	rws *http2responseWriterState
+}
+
+// Optional http.ResponseWriter interfaces implemented.
+var (
+	_ CloseNotifier     = (*http2responseWriter)(nil)
+	_ Flusher           = (*http2responseWriter)(nil)
+	_ http2stringWriter = (*http2responseWriter)(nil)
+)
+
+type http2responseWriterState struct {
+	// immutable within a request:
+	stream *http2stream
+	req    *Request
+	body   *http2requestBody // to close at end of request, if DATA frames didn't
+	conn   *http2serverConn
+
+	// TODO: adjust buffer writing sizes based on server config, frame size updates from peer, etc
+	bw *bufio.Writer // writing to a chunkWriter{this *responseWriterState}
+
+	// mutated by http.Handler goroutine:
+	handlerHeader Header   // nil until called
+	snapHeader    Header   // snapshot of handlerHeader at WriteHeader time
+	trailers      []string // set in writeChunk
+	status        int      // status code passed to WriteHeader
+	wroteHeader   bool     // WriteHeader called (explicitly or implicitly). Not necessarily sent to user yet.
+	sentHeader    bool     // have we sent the header frame?
+	handlerDone   bool     // handler has finished
+	dirty         bool     // a Write failed; don't reuse this responseWriterState
+
+	sentContentLen int64 // non-zero if handler set a Content-Length header
+	wroteBytes     int64
+
+	closeNotifierMu sync.Mutex // guards closeNotifierCh
+	closeNotifierCh chan bool  // nil until first used
+}
+
+type http2chunkWriter struct{ rws *http2responseWriterState }
+
+func (cw http2chunkWriter) Write(p []byte) (n int, err error) { return cw.rws.writeChunk(p) }
+
+func (rws *http2responseWriterState) hasTrailers() bool { return len(rws.trailers) > 0 }
+
+func (rws *http2responseWriterState) hasNonemptyTrailers() bool {
+	for _, trailer := range rws.trailers {
+		if _, ok := rws.handlerHeader[trailer]; ok {
+			return true
+		}
+	}
+	return false
+}
+
+// declareTrailer is called for each Trailer header when the
+// response header is written. It notes that a header will need to be
+// written in the trailers at the end of the response.
+func (rws *http2responseWriterState) declareTrailer(k string) {
+	k = CanonicalHeaderKey(k)
+	if !httpguts.ValidTrailerHeader(k) {
+		// Forbidden by RFC 7230, section 4.1.2.
+		rws.conn.logf("ignoring invalid trailer %q", k)
+		return
+	}
+	if !http2strSliceContains(rws.trailers, k) {
+		rws.trailers = append(rws.trailers, k)
+	}
+}
+
+// writeChunk writes chunks from the bufio.Writer. But because
+// bufio.Writer may bypass its chunking, sometimes p may be
+// arbitrarily large.
+//
+// writeChunk is also responsible (on the first chunk) for sending the
+// HEADER response.
+func (rws *http2responseWriterState) writeChunk(p []byte) (n int, err error) {
+	if !rws.wroteHeader {
+		rws.writeHeader(200)
+	}
+
+	isHeadResp := rws.req.Method == "HEAD"
+	if !rws.sentHeader {
+		rws.sentHeader = true
+		var ctype, clen string
+		if clen = rws.snapHeader.Get("Content-Length"); clen != "" {
+			rws.snapHeader.Del("Content-Length")
+			if cl, err := strconv.ParseUint(clen, 10, 63); err == nil {
+				rws.sentContentLen = int64(cl)
+			} else {
+				clen = ""
+			}
+		}
+		if clen == "" && rws.handlerDone && http2bodyAllowedForStatus(rws.status) && (len(p) > 0 || !isHeadResp) {
+			clen = strconv.Itoa(len(p))
+		}
+		_, hasContentType := rws.snapHeader["Content-Type"]
+		// If the Content-Encoding is non-blank, we shouldn't
+		// sniff the body. See Issue golang.org/issue/31753.
+		ce := rws.snapHeader.Get("Content-Encoding")
+		hasCE := len(ce) > 0
+		if !hasCE && !hasContentType && http2bodyAllowedForStatus(rws.status) && len(p) > 0 {
+			ctype = DetectContentType(p)
+		}
+		var date string
+		if _, ok := rws.snapHeader["Date"]; !ok {
+			// TODO(bradfitz): be faster here, like net/http? measure.
+			date = time.Now().UTC().Format(TimeFormat)
+		}
+
+		for _, v := range rws.snapHeader["Trailer"] {
+			http2foreachHeaderElement(v, rws.declareTrailer)
+		}
+
+		// "Connection" headers aren't allowed in HTTP/2 (RFC 7540, 8.1.2.2),
+		// but respect "Connection" == "close" to mean sending a GOAWAY and tearing
+		// down the TCP connection when idle, like we do for HTTP/1.
+		// TODO: remove more Connection-specific header fields here, in addition
+		// to "Connection".
+		if _, ok := rws.snapHeader["Connection"]; ok {
+			v := rws.snapHeader.Get("Connection")
+			delete(rws.snapHeader, "Connection")
+			if v == "close" {
+				rws.conn.startGracefulShutdown()
+			}
+		}
+
+		endStream := (rws.handlerDone && !rws.hasTrailers() && len(p) == 0) || isHeadResp
+		err = rws.conn.writeHeaders(rws.stream, &http2writeResHeaders{
+			streamID:      rws.stream.id,
+			httpResCode:   rws.status,
+			h:             rws.snapHeader,
+			endStream:     endStream,
+			contentType:   ctype,
+			contentLength: clen,
+			date:          date,
+		})
+		if err != nil {
+			rws.dirty = true
+			return 0, err
+		}
+		if endStream {
+			return 0, nil
+		}
+	}
+	if isHeadResp {
+		return len(p), nil
+	}
+	if len(p) == 0 && !rws.handlerDone {
+		return 0, nil
+	}
+
+	if rws.handlerDone {
+		rws.promoteUndeclaredTrailers()
+	}
+
+	// only send trailers if they have actually been defined by the
+	// server handler.
+	hasNonemptyTrailers := rws.hasNonemptyTrailers()
+	endStream := rws.handlerDone && !hasNonemptyTrailers
+	if len(p) > 0 || endStream {
+		// only send a 0 byte DATA frame if we're ending the stream.
+		if err := rws.conn.writeDataFromHandler(rws.stream, p, endStream); err != nil {
+			rws.dirty = true
+			return 0, err
+		}
+	}
+
+	if rws.handlerDone && hasNonemptyTrailers {
+		err = rws.conn.writeHeaders(rws.stream, &http2writeResHeaders{
+			streamID:  rws.stream.id,
+			h:         rws.handlerHeader,
+			trailers:  rws.trailers,
+			endStream: true,
+		})
+		if err != nil {
+			rws.dirty = true
+		}
+		return len(p), err
+	}
+	return len(p), nil
+}
+
+// TrailerPrefix is a magic prefix for ResponseWriter.Header map keys
+// that, if present, signals that the map entry is actually for
+// the response trailers, and not the response headers. The prefix
+// is stripped after the ServeHTTP call finishes and the values are
+// sent in the trailers.
+//
+// This mechanism is intended only for trailers that are not known
+// prior to the headers being written. If the set of trailers is fixed
+// or known before the header is written, the normal Go trailers mechanism
+// is preferred:
+//
+//	https://golang.org/pkg/net/http/#ResponseWriter
+//	https://golang.org/pkg/net/http/#example_ResponseWriter_trailers
+const http2TrailerPrefix = "Trailer:"
+
+// promoteUndeclaredTrailers permits http.Handlers to set trailers
+// after the header has already been flushed. Because the Go
+// ResponseWriter interface has no way to set Trailers (only the
+// Header), and because we didn't want to expand the ResponseWriter
+// interface, and because nobody used trailers, and because RFC 7230
+// says you SHOULD (but not must) predeclare any trailers in the
+// header, the official ResponseWriter rules said trailers in Go must
+// be predeclared, and then we reuse the same ResponseWriter.Header()
+// map to mean both Headers and Trailers. When it's time to write the
+// Trailers, we pick out the fields of Headers that were declared as
+// trailers. That worked for a while, until we found the first major
+// user of Trailers in the wild: gRPC (using them only over http2),
+// and gRPC libraries permit setting trailers mid-stream without
+// predeclaring them. So: change of plans. We still permit the old
+// way, but we also permit this hack: if a Header() key begins with
+// "Trailer:", the suffix of that key is a Trailer. Because ':' is an
+// invalid token byte anyway, there is no ambiguity. (And it's already
+// filtered out) It's mildly hacky, but not terrible.
+//
+// This method runs after the Handler is done and promotes any Header
+// fields to be trailers.
+func (rws *http2responseWriterState) promoteUndeclaredTrailers() {
+	for k, vv := range rws.handlerHeader {
+		if !strings.HasPrefix(k, http2TrailerPrefix) {
+			continue
+		}
+		trailerKey := strings.TrimPrefix(k, http2TrailerPrefix)
+		rws.declareTrailer(trailerKey)
+		rws.handlerHeader[CanonicalHeaderKey(trailerKey)] = vv
+	}
+
+	if len(rws.trailers) > 1 {
+		sorter := http2sorterPool.Get().(*http2sorter)
+		sorter.SortStrings(rws.trailers)
+		http2sorterPool.Put(sorter)
+	}
+}
+
+func (w *http2responseWriter) Flush() {
+	rws := w.rws
+	if rws == nil {
+		panic("Header called after Handler finished")
+	}
+	if rws.bw.Buffered() > 0 {
+		if err := rws.bw.Flush(); err != nil {
+			// Ignore the error. The frame writer already knows.
+			return
+		}
+	} else {
+		// The bufio.Writer won't call chunkWriter.Write
+		// (writeChunk with zero bytes, so we have to do it
+		// ourselves to force the HTTP response header and/or
+		// final DATA frame (with END_STREAM) to be sent.
+		rws.writeChunk(nil)
+	}
+}
+
+func (w *http2responseWriter) CloseNotify() <-chan bool {
+	rws := w.rws
+	if rws == nil {
+		panic("CloseNotify called after Handler finished")
+	}
+	rws.closeNotifierMu.Lock()
+	ch := rws.closeNotifierCh
+	if ch == nil {
+		ch = make(chan bool, 1)
+		rws.closeNotifierCh = ch
+		cw := rws.stream.cw
+		go func() {
+			cw.Wait() // wait for close
+			ch <- true
+		}()
+	}
+	rws.closeNotifierMu.Unlock()
+	return ch
+}
+
+func (w *http2responseWriter) Header() Header {
+	rws := w.rws
+	if rws == nil {
+		panic("Header called after Handler finished")
+	}
+	if rws.handlerHeader == nil {
+		rws.handlerHeader = make(Header)
+	}
+	return rws.handlerHeader
+}
+
+// checkWriteHeaderCode is a copy of net/http's checkWriteHeaderCode.
+func http2checkWriteHeaderCode(code int) {
+	// Issue 22880: require valid WriteHeader status codes.
+	// For now we only enforce that it's three digits.
+	// In the future we might block things over 599 (600 and above aren't defined
+	// at http://httpwg.org/specs/rfc7231.html#status.codes).
+	// But for now any three digits.
+	//
+	// We used to send "HTTP/1.1 000 0" on the wire in responses but there's
+	// no equivalent bogus thing we can realistically send in HTTP/2,
+	// so we'll consistently panic instead and help people find their bugs
+	// early. (We can't return an error from WriteHeader even if we wanted to.)
+	if code < 100 || code > 999 {
+		panic(fmt.Sprintf("invalid WriteHeader code %v", code))
+	}
+}
+
+func (w *http2responseWriter) WriteHeader(code int) {
+	rws := w.rws
+	if rws == nil {
+		panic("WriteHeader called after Handler finished")
+	}
+	rws.writeHeader(code)
+}
+
+func (rws *http2responseWriterState) writeHeader(code int) {
+	if rws.wroteHeader {
+		return
+	}
+
+	http2checkWriteHeaderCode(code)
+
+	// Handle informational headers
+	if code >= 100 && code <= 199 {
+		// Per RFC 8297 we must not clear the current header map
+		h := rws.handlerHeader
+
+		_, cl := h["Content-Length"]
+		_, te := h["Transfer-Encoding"]
+		if cl || te {
+			h = h.Clone()
+			h.Del("Content-Length")
+			h.Del("Transfer-Encoding")
+		}
+
+		if rws.conn.writeHeaders(rws.stream, &http2writeResHeaders{
+			streamID:    rws.stream.id,
+			httpResCode: code,
+			h:           h,
+			endStream:   rws.handlerDone && !rws.hasTrailers(),
+		}) != nil {
+			rws.dirty = true
+		}
+
+		return
+	}
+
+	rws.wroteHeader = true
+	rws.status = code
+	if len(rws.handlerHeader) > 0 {
+		rws.snapHeader = http2cloneHeader(rws.handlerHeader)
+	}
+}
+
+func http2cloneHeader(h Header) Header {
+	h2 := make(Header, len(h))
+	for k, vv := range h {
+		vv2 := make([]string, len(vv))
+		copy(vv2, vv)
+		h2[k] = vv2
+	}
+	return h2
+}
+
+// The Life Of A Write is like this:
+//
+// * Handler calls w.Write or w.WriteString ->
+// * -> rws.bw (*bufio.Writer) ->
+// * (Handler might call Flush)
+// * -> chunkWriter{rws}
+// * -> responseWriterState.writeChunk(p []byte)
+// * -> responseWriterState.writeChunk (most of the magic; see comment there)
+func (w *http2responseWriter) Write(p []byte) (n int, err error) {
+	return w.write(len(p), p, "")
+}
+
+func (w *http2responseWriter) WriteString(s string) (n int, err error) {
+	return w.write(len(s), nil, s)
+}
+
+// either dataB or dataS is non-zero.
+func (w *http2responseWriter) write(lenData int, dataB []byte, dataS string) (n int, err error) {
+	rws := w.rws
+	if rws == nil {
+		panic("Write called after Handler finished")
+	}
+	if !rws.wroteHeader {
+		w.WriteHeader(200)
+	}
+	if !http2bodyAllowedForStatus(rws.status) {
+		return 0, ErrBodyNotAllowed
+	}
+	rws.wroteBytes += int64(len(dataB)) + int64(len(dataS)) // only one can be set
+	if rws.sentContentLen != 0 && rws.wroteBytes > rws.sentContentLen {
+		// TODO: send a RST_STREAM
+		return 0, errors.New("http2: handler wrote more than declared Content-Length")
+	}
+
+	if dataB != nil {
+		return rws.bw.Write(dataB)
+	} else {
+		return rws.bw.WriteString(dataS)
+	}
+}
+
+func (w *http2responseWriter) handlerDone() {
+	rws := w.rws
+	dirty := rws.dirty
+	rws.handlerDone = true
+	w.Flush()
+	w.rws = nil
+	if !dirty {
+		// Only recycle the pool if all prior Write calls to
+		// the serverConn goroutine completed successfully. If
+		// they returned earlier due to resets from the peer
+		// there might still be write goroutines outstanding
+		// from the serverConn referencing the rws memory. See
+		// issue 20704.
+		http2responseWriterStatePool.Put(rws)
+	}
+}
+
+// Push errors.
+var (
+	http2ErrRecursivePush    = errors.New("http2: recursive push not allowed")
+	http2ErrPushLimitReached = errors.New("http2: push would exceed peer's SETTINGS_MAX_CONCURRENT_STREAMS")
+)
+
+var _ Pusher = (*http2responseWriter)(nil)
+
+func (w *http2responseWriter) Push(target string, opts *PushOptions) error {
+	st := w.rws.stream
+	sc := st.sc
+	sc.serveG.checkNotOn()
+
+	// No recursive pushes: "PUSH_PROMISE frames MUST only be sent on a peer-initiated stream."
+	// http://tools.ietf.org/html/rfc7540#section-6.6
+	if st.isPushed() {
+		return http2ErrRecursivePush
+	}
+
+	if opts == nil {
+		opts = new(PushOptions)
+	}
+
+	// Default options.
+	if opts.Method == "" {
+		opts.Method = "GET"
+	}
+	if opts.Header == nil {
+		opts.Header = Header{}
+	}
+	wantScheme := "http"
+	if w.rws.req.TLS != nil {
+		wantScheme = "https"
+	}
+
+	// Validate the request.
+	u, err := url.Parse(target)
+	if err != nil {
+		return err
+	}
+	if u.Scheme == "" {
+		if !strings.HasPrefix(target, "/") {
+			return fmt.Errorf("target must be an absolute URL or an absolute path: %q", target)
+		}
+		u.Scheme = wantScheme
+		u.Host = w.rws.req.Host
+	} else {
+		if u.Scheme != wantScheme {
+			return fmt.Errorf("cannot push URL with scheme %q from request with scheme %q", u.Scheme, wantScheme)
+		}
+		if u.Host == "" {
+			return errors.New("URL must have a host")
+		}
+	}
+	for k := range opts.Header {
+		if strings.HasPrefix(k, ":") {
+			return fmt.Errorf("promised request headers cannot include pseudo header %q", k)
+		}
+		// These headers are meaningful only if the request has a body,
+		// but PUSH_PROMISE requests cannot have a body.
+		// http://tools.ietf.org/html/rfc7540#section-8.2
+		// Also disallow Host, since the promised URL must be absolute.
+		if http2asciiEqualFold(k, "content-length") ||
+			http2asciiEqualFold(k, "content-encoding") ||
+			http2asciiEqualFold(k, "trailer") ||
+			http2asciiEqualFold(k, "te") ||
+			http2asciiEqualFold(k, "expect") ||
+			http2asciiEqualFold(k, "host") {
+			return fmt.Errorf("promised request headers cannot include %q", k)
+		}
+	}
+	if err := http2checkValidHTTP2RequestHeaders(opts.Header); err != nil {
+		return err
+	}
+
+	// The RFC effectively limits promised requests to GET and HEAD:
+	// "Promised requests MUST be cacheable [GET, HEAD, or POST], and MUST be safe [GET or HEAD]"
+	// http://tools.ietf.org/html/rfc7540#section-8.2
+	if opts.Method != "GET" && opts.Method != "HEAD" {
+		return fmt.Errorf("method %q must be GET or HEAD", opts.Method)
+	}
+
+	msg := &http2startPushRequest{
+		parent: st,
+		method: opts.Method,
+		url:    u,
+		header: http2cloneHeader(opts.Header),
+		done:   http2errChanPool.Get().(chan error),
+	}
+
+	select {
+	case <-sc.doneServing:
+		return http2errClientDisconnected
+	case <-st.cw:
+		return http2errStreamClosed
+	case sc.serveMsgCh <- msg:
+	}
+
+	select {
+	case <-sc.doneServing:
+		return http2errClientDisconnected
+	case <-st.cw:
+		return http2errStreamClosed
+	case err := <-msg.done:
+		http2errChanPool.Put(msg.done)
+		return err
+	}
+}
+
+type http2startPushRequest struct {
+	parent *http2stream
+	method string
+	url    *url.URL
+	header Header
+	done   chan error
+}
+
+func (sc *http2serverConn) startPush(msg *http2startPushRequest) {
+	sc.serveG.check()
+
+	// http://tools.ietf.org/html/rfc7540#section-6.6.
+	// PUSH_PROMISE frames MUST only be sent on a peer-initiated stream that
+	// is in either the "open" or "half-closed (remote)" state.
+	if msg.parent.state != http2stateOpen && msg.parent.state != http2stateHalfClosedRemote {
+		// responseWriter.Push checks that the stream is peer-initiated.
+		msg.done <- http2errStreamClosed
+		return
+	}
+
+	// http://tools.ietf.org/html/rfc7540#section-6.6.
+	if !sc.pushEnabled {
+		msg.done <- ErrNotSupported
+		return
+	}
+
+	// PUSH_PROMISE frames must be sent in increasing order by stream ID, so
+	// we allocate an ID for the promised stream lazily, when the PUSH_PROMISE
+	// is written. Once the ID is allocated, we start the request handler.
+	allocatePromisedID := func() (uint32, error) {
+		sc.serveG.check()
+
+		// Check this again, just in case. Technically, we might have received
+		// an updated SETTINGS by the time we got around to writing this frame.
+		if !sc.pushEnabled {
+			return 0, ErrNotSupported
+		}
+		// http://tools.ietf.org/html/rfc7540#section-6.5.2.
+		if sc.curPushedStreams+1 > sc.clientMaxStreams {
+			return 0, http2ErrPushLimitReached
+		}
+
+		// http://tools.ietf.org/html/rfc7540#section-5.1.1.
+		// Streams initiated by the server MUST use even-numbered identifiers.
+		// A server that is unable to establish a new stream identifier can send a GOAWAY
+		// frame so that the client is forced to open a new connection for new streams.
+		if sc.maxPushPromiseID+2 >= 1<<31 {
+			sc.startGracefulShutdownInternal()
+			return 0, http2ErrPushLimitReached
+		}
+		sc.maxPushPromiseID += 2
+		promisedID := sc.maxPushPromiseID
+
+		// http://tools.ietf.org/html/rfc7540#section-8.2.
+		// Strictly speaking, the new stream should start in "reserved (local)", then
+		// transition to "half closed (remote)" after sending the initial HEADERS, but
+		// we start in "half closed (remote)" for simplicity.
+		// See further comments at the definition of stateHalfClosedRemote.
+		promised := sc.newStream(promisedID, msg.parent.id, http2stateHalfClosedRemote)
+		rw, req, err := sc.newWriterAndRequestNoBody(promised, http2requestParam{
+			method:    msg.method,
+			scheme:    msg.url.Scheme,
+			authority: msg.url.Host,
+			path:      msg.url.RequestURI(),
+			header:    http2cloneHeader(msg.header), // clone since handler runs concurrently with writing the PUSH_PROMISE
+		})
+		if err != nil {
+			// Should not happen, since we've already validated msg.url.
+			panic(fmt.Sprintf("newWriterAndRequestNoBody(%+v): %v", msg.url, err))
+		}
+
+		go sc.runHandler(rw, req, sc.handler.ServeHTTP)
+		return promisedID, nil
+	}
+
+	sc.writeFrame(http2FrameWriteRequest{
+		write: &http2writePushPromise{
+			streamID:           msg.parent.id,
+			method:             msg.method,
+			url:                msg.url,
+			h:                  msg.header,
+			allocatePromisedID: allocatePromisedID,
+		},
+		stream: msg.parent,
+		done:   msg.done,
+	})
+}
+
+// foreachHeaderElement splits v according to the "#rule" construction
+// in RFC 7230 section 7 and calls fn for each non-empty element.
+func http2foreachHeaderElement(v string, fn func(string)) {
+	v = textproto.TrimString(v)
+	if v == "" {
+		return
+	}
+	if !strings.Contains(v, ",") {
+		fn(v)
+		return
+	}
+	for _, f := range strings.Split(v, ",") {
+		if f = textproto.TrimString(f); f != "" {
+			fn(f)
+		}
+	}
+}
+
+// From http://httpwg.org/specs/rfc7540.html#rfc.section.8.1.2.2
+var http2connHeaders = []string{
+	"Connection",
+	"Keep-Alive",
+	"Proxy-Connection",
+	"Transfer-Encoding",
+	"Upgrade",
+}
+
+// checkValidHTTP2RequestHeaders checks whether h is a valid HTTP/2 request,
+// per RFC 7540 Section 8.1.2.2.
+// The returned error is reported to users.
+func http2checkValidHTTP2RequestHeaders(h Header) error {
+	for _, k := range http2connHeaders {
+		if _, ok := h[k]; ok {
+			return fmt.Errorf("request header %q is not valid in HTTP/2", k)
+		}
+	}
+	te := h["Te"]
+	if len(te) > 0 && (len(te) > 1 || (te[0] != "trailers" && te[0] != "")) {
+		return errors.New(`request header "TE" may only be "trailers" in HTTP/2`)
+	}
+	return nil
+}
+
+func http2new400Handler(err error) HandlerFunc {
+	return func(w ResponseWriter, r *Request) {
+		Error(w, err.Error(), StatusBadRequest)
+	}
+}
+
+// h1ServerKeepAlivesDisabled reports whether hs has its keep-alives
+// disabled. See comments on h1ServerShutdownChan above for why
+// the code is written this way.
+func http2h1ServerKeepAlivesDisabled(hs *Server) bool {
+	var x interface{} = hs
+	type I interface {
+		doKeepAlives() bool
+	}
+	if hs, ok := x.(I); ok {
+		return !hs.doKeepAlives()
+	}
+	return false
+}
+
+func (sc *http2serverConn) countError(name string, err error) error {
+	if sc == nil || sc.srv == nil {
+		return err
+	}
+	f := sc.srv.CountError
+	if f == nil {
+		return err
+	}
+	var typ string
+	var code http2ErrCode
+	switch e := err.(type) {
+	case http2ConnectionError:
+		typ = "conn"
+		code = http2ErrCode(e)
+	case http2StreamError:
+		typ = "stream"
+		code = http2ErrCode(e.Code)
+	default:
+		return err
+	}
+	codeStr := http2errCodeName[code]
+	if codeStr == "" {
+		codeStr = strconv.Itoa(int(code))
+	}
+	f(fmt.Sprintf("%s_%s_%s", typ, codeStr, name))
+	return err
+}
+
+const (
+	// transportDefaultConnFlow is how many connection-level flow control
+	// tokens we give the server at start-up, past the default 64k.
+	http2transportDefaultConnFlow = 1 << 30
+
+	// transportDefaultStreamFlow is how many stream-level flow
+	// control tokens we announce to the peer, and how many bytes
+	// we buffer per stream.
+	http2transportDefaultStreamFlow = 4 << 20
+
+	// transportDefaultStreamMinRefresh is the minimum number of bytes we'll send
+	// a stream-level WINDOW_UPDATE for at a time.
+	http2transportDefaultStreamMinRefresh = 4 << 10
+
+	http2defaultUserAgent = "Go-http-client/2.0"
+
+	// initialMaxConcurrentStreams is a connections maxConcurrentStreams until
+	// it's received servers initial SETTINGS frame, which corresponds with the
+	// spec's minimum recommended value.
+	http2initialMaxConcurrentStreams = 100
+
+	// defaultMaxConcurrentStreams is a connections default maxConcurrentStreams
+	// if the server doesn't include one in its initial SETTINGS frame.
+	http2defaultMaxConcurrentStreams = 1000
+)
+
+// Transport is an HTTP/2 Transport.
+//
+// A Transport internally caches connections to servers. It is safe
+// for concurrent use by multiple goroutines.
+type http2Transport struct {
+	// DialTLS specifies an optional dial function for creating
+	// TLS connections for requests.
+	//
+	// If DialTLS is nil, tls.Dial is used.
+	//
+	// If the returned net.Conn has a ConnectionState method like tls.Conn,
+	// it will be used to set http.Response.TLS.
+	DialTLS func(network, addr string, cfg *tls.Config) (net.Conn, error)
+
+	// TLSClientConfig specifies the TLS configuration to use with
+	// tls.Client. If nil, the default configuration is used.
+	TLSClientConfig *tls.Config
+
+	// ConnPool optionally specifies an alternate connection pool to use.
+	// If nil, the default is used.
+	ConnPool http2ClientConnPool
+
+	// DisableCompression, if true, prevents the Transport from
+	// requesting compression with an "Accept-Encoding: gzip"
+	// request header when the Request contains no existing
+	// Accept-Encoding value. If the Transport requests gzip on
+	// its own and gets a gzipped response, it's transparently
+	// decoded in the Response.Body. However, if the user
+	// explicitly requested gzip it is not automatically
+	// uncompressed.
+	DisableCompression bool
+
+	// AllowHTTP, if true, permits HTTP/2 requests using the insecure,
+	// plain-text "http" scheme. Note that this does not enable h2c support.
+	AllowHTTP bool
+
+	// MaxHeaderListSize is the http2 SETTINGS_MAX_HEADER_LIST_SIZE to
+	// send in the initial settings frame. It is how many bytes
+	// of response headers are allowed. Unlike the http2 spec, zero here
+	// means to use a default limit (currently 10MB). If you actually
+	// want to advertise an unlimited value to the peer, Transport
+	// interprets the highest possible value here (0xffffffff or 1<<32-1)
+	// to mean no limit.
+	MaxHeaderListSize uint32
+
+	// StrictMaxConcurrentStreams controls whether the server's
+	// SETTINGS_MAX_CONCURRENT_STREAMS should be respected
+	// globally. If false, new TCP connections are created to the
+	// server as needed to keep each under the per-connection
+	// SETTINGS_MAX_CONCURRENT_STREAMS limit. If true, the
+	// server's SETTINGS_MAX_CONCURRENT_STREAMS is interpreted as
+	// a global limit and callers of RoundTrip block when needed,
+	// waiting for their turn.
+	StrictMaxConcurrentStreams bool
+
+	// ReadIdleTimeout is the timeout after which a health check using ping
+	// frame will be carried out if no frame is received on the connection.
+	// Note that a ping response will is considered a received frame, so if
+	// there is no other traffic on the connection, the health check will
+	// be performed every ReadIdleTimeout interval.
+	// If zero, no health check is performed.
+	ReadIdleTimeout time.Duration
+
+	// PingTimeout is the timeout after which the connection will be closed
+	// if a response to Ping is not received.
+	// Defaults to 15s.
+	PingTimeout time.Duration
+
+	// WriteByteTimeout is the timeout after which the connection will be
+	// closed no data can be written to it. The timeout begins when data is
+	// available to write, and is extended whenever any bytes are written.
+	WriteByteTimeout time.Duration
+
+	// CountError, if non-nil, is called on HTTP/2 transport errors.
+	// It's intended to increment a metric for monitoring, such
+	// as an expvar or Prometheus metric.
+	// The errType consists of only ASCII word characters.
+	CountError func(errType string)
+
+	// t1, if non-nil, is the standard library Transport using
+	// this transport. Its settings are used (but not its
+	// RoundTrip method, etc).
+	t1 *Transport
+
+	connPoolOnce  sync.Once
+	connPoolOrDef http2ClientConnPool // non-nil version of ConnPool
+}
+
+func (t *http2Transport) maxHeaderListSize() uint32 {
+	if t.MaxHeaderListSize == 0 {
+		return 10 << 20
+	}
+	if t.MaxHeaderListSize == 0xffffffff {
+		return 0
+	}
+	return t.MaxHeaderListSize
+}
+
+func (t *http2Transport) disableCompression() bool {
+	return t.DisableCompression || (t.t1 != nil && t.t1.DisableCompression)
+}
+
+func (t *http2Transport) pingTimeout() time.Duration {
+	if t.PingTimeout == 0 {
+		return 15 * time.Second
+	}
+	return t.PingTimeout
+
+}
+
+// ConfigureTransport configures a net/http HTTP/1 Transport to use HTTP/2.
+// It returns an error if t1 has already been HTTP/2-enabled.
+//
+// Use ConfigureTransports instead to configure the HTTP/2 Transport.
+func http2ConfigureTransport(t1 *Transport) error {
+	_, err := http2ConfigureTransports(t1)
+	return err
+}
+
+// ConfigureTransports configures a net/http HTTP/1 Transport to use HTTP/2.
+// It returns a new HTTP/2 Transport for further configuration.
+// It returns an error if t1 has already been HTTP/2-enabled.
+func http2ConfigureTransports(t1 *Transport) (*http2Transport, error) {
+	return http2configureTransports(t1)
+}
+
+func http2configureTransports(t1 *Transport) (*http2Transport, error) {
+	connPool := new(http2clientConnPool)
+	t2 := &http2Transport{
+		ConnPool: http2noDialClientConnPool{connPool},
+		t1:       t1,
+	}
+	connPool.t = t2
+	if err := http2registerHTTPSProtocol(t1, http2noDialH2RoundTripper{t2}); err != nil {
+		return nil, err
+	}
+	if t1.TLSClientConfig == nil {
+		t1.TLSClientConfig = new(tls.Config)
+	}
+	if !http2strSliceContains(t1.TLSClientConfig.NextProtos, "h2") {
+		t1.TLSClientConfig.NextProtos = append([]string{"h2"}, t1.TLSClientConfig.NextProtos...)
+	}
+	if !http2strSliceContains(t1.TLSClientConfig.NextProtos, "http/1.1") {
+		t1.TLSClientConfig.NextProtos = append(t1.TLSClientConfig.NextProtos, "http/1.1")
+	}
+	upgradeFn := func(authority string, c *tls.Conn) RoundTripper {
+		addr := http2authorityAddr("https", authority)
+		if used, err := connPool.addConnIfNeeded(addr, t2, c); err != nil {
+			go c.Close()
+			return http2erringRoundTripper{err}
+		} else if !used {
+			// Turns out we don't need this c.
+			// For example, two goroutines made requests to the same host
+			// at the same time, both kicking off TCP dials. (since protocol
+			// was unknown)
+			go c.Close()
+		}
+		return t2
+	}
+	if m := t1.TLSNextProto; len(m) == 0 {
+		t1.TLSNextProto = map[string]func(string, *tls.Conn) RoundTripper{
+			"h2": upgradeFn,
+		}
+	} else {
+		m["h2"] = upgradeFn
+	}
+	return t2, nil
+}
+
+func (t *http2Transport) connPool() http2ClientConnPool {
+	t.connPoolOnce.Do(t.initConnPool)
+	return t.connPoolOrDef
+}
+
+func (t *http2Transport) initConnPool() {
+	if t.ConnPool != nil {
+		t.connPoolOrDef = t.ConnPool
+	} else {
+		t.connPoolOrDef = &http2clientConnPool{t: t}
+	}
+}
+
+// ClientConn is the state of a single HTTP/2 client connection to an
+// HTTP/2 server.
+type http2ClientConn struct {
+	t             *http2Transport
+	tconn         net.Conn             // usually *tls.Conn, except specialized impls
+	tlsState      *tls.ConnectionState // nil only for specialized impls
+	reused        uint32               // whether conn is being reused; atomic
+	singleUse     bool                 // whether being used for a single http.Request
+	getConnCalled bool                 // used by clientConnPool
+
+	// readLoop goroutine fields:
+	readerDone chan struct{} // closed on error
+	readerErr  error         // set before readerDone is closed
+
+	idleTimeout time.Duration // or 0 for never
+	idleTimer   *time.Timer
+
+	mu              sync.Mutex // guards following
+	cond            *sync.Cond // hold mu; broadcast on flow/closed changes
+	flow            http2flow  // our conn-level flow control quota (cs.flow is per stream)
+	inflow          http2flow  // peer's conn-level flow control
+	doNotReuse      bool       // whether conn is marked to not be reused for any future requests
+	closing         bool
+	closed          bool
+	seenSettings    bool                          // true if we've seen a settings frame, false otherwise
+	wantSettingsAck bool                          // we sent a SETTINGS frame and haven't heard back
+	goAway          *http2GoAwayFrame             // if non-nil, the GoAwayFrame we received
+	goAwayDebug     string                        // goAway frame's debug data, retained as a string
+	streams         map[uint32]*http2clientStream // client-initiated
+	streamsReserved int                           // incr by ReserveNewRequest; decr on RoundTrip
+	nextStreamID    uint32
+	pendingRequests int                       // requests blocked and waiting to be sent because len(streams) == maxConcurrentStreams
+	pings           map[[8]byte]chan struct{} // in flight ping data to notification channel
+	br              *bufio.Reader
+	lastActive      time.Time
+	lastIdle        time.Time // time last idle
+	// Settings from peer: (also guarded by wmu)
+	maxFrameSize          uint32
+	maxConcurrentStreams  uint32
+	peerMaxHeaderListSize uint64
+	initialWindowSize     uint32
+
+	// reqHeaderMu is a 1-element semaphore channel controlling access to sending new requests.
+	// Write to reqHeaderMu to lock it, read from it to unlock.
+	// Lock reqmu BEFORE mu or wmu.
+	reqHeaderMu chan struct{}
+
+	// wmu is held while writing.
+	// Acquire BEFORE mu when holding both, to avoid blocking mu on network writes.
+	// Only acquire both at the same time when changing peer settings.
+	wmu  sync.Mutex
+	bw   *bufio.Writer
+	fr   *http2Framer
+	werr error        // first write error that has occurred
+	hbuf bytes.Buffer // HPACK encoder writes into this
+	henc *hpack.Encoder
+}
+
+// clientStream is the state for a single HTTP/2 stream. One of these
+// is created for each Transport.RoundTrip call.
+type http2clientStream struct {
+	cc *http2ClientConn
+
+	// Fields of Request that we may access even after the response body is closed.
+	ctx       context.Context
+	reqCancel <-chan struct{}
+
+	trace         *httptrace.ClientTrace // or nil
+	ID            uint32
+	bufPipe       http2pipe // buffered pipe with the flow-controlled response payload
+	requestedGzip bool
+	isHead        bool
+
+	abortOnce sync.Once
+	abort     chan struct{} // closed to signal stream should end immediately
+	abortErr  error         // set if abort is closed
+
+	peerClosed chan struct{} // closed when the peer sends an END_STREAM flag
+	donec      chan struct{} // closed after the stream is in the closed state
+	on100      chan struct{} // buffered; written to if a 100 is received
+
+	respHeaderRecv chan struct{} // closed when headers are received
+	res            *Response     // set if respHeaderRecv is closed
+
+	flow        http2flow // guarded by cc.mu
+	inflow      http2flow // guarded by cc.mu
+	bytesRemain int64     // -1 means unknown; owned by transportResponseBody.Read
+	readErr     error     // sticky read error; owned by transportResponseBody.Read
+
+	reqBody              io.ReadCloser
+	reqBodyContentLength int64 // -1 means unknown
+	reqBodyClosed        bool  // body has been closed; guarded by cc.mu
+
+	// owned by writeRequest:
+	sentEndStream bool // sent an END_STREAM flag to the peer
+	sentHeaders   bool
+
+	// owned by clientConnReadLoop:
+	firstByte    bool  // got the first response byte
+	pastHeaders  bool  // got first MetaHeadersFrame (actual headers)
+	pastTrailers bool  // got optional second MetaHeadersFrame (trailers)
+	num1xx       uint8 // number of 1xx responses seen
+	readClosed   bool  // peer sent an END_STREAM flag
+	readAborted  bool  // read loop reset the stream
+
+	trailer    Header  // accumulated trailers
+	resTrailer *Header // client's Response.Trailer
+}
+
+var http2got1xxFuncForTests func(int, textproto.MIMEHeader) error
+
+// get1xxTraceFunc returns the value of request's httptrace.ClientTrace.Got1xxResponse func,
+// if any. It returns nil if not set or if the Go version is too old.
+func (cs *http2clientStream) get1xxTraceFunc() func(int, textproto.MIMEHeader) error {
+	if fn := http2got1xxFuncForTests; fn != nil {
+		return fn
+	}
+	return http2traceGot1xxResponseFunc(cs.trace)
+}
+
+func (cs *http2clientStream) abortStream(err error) {
+	cs.cc.mu.Lock()
+	defer cs.cc.mu.Unlock()
+	cs.abortStreamLocked(err)
+}
+
+func (cs *http2clientStream) abortStreamLocked(err error) {
+	cs.abortOnce.Do(func() {
+		cs.abortErr = err
+		close(cs.abort)
+	})
+	if cs.reqBody != nil && !cs.reqBodyClosed {
+		cs.reqBody.Close()
+		cs.reqBodyClosed = true
+	}
+	// TODO(dneil): Clean up tests where cs.cc.cond is nil.
+	if cs.cc.cond != nil {
+		// Wake up writeRequestBody if it is waiting on flow control.
+		cs.cc.cond.Broadcast()
+	}
+}
+
+func (cs *http2clientStream) abortRequestBodyWrite() {
+	cc := cs.cc
+	cc.mu.Lock()
+	defer cc.mu.Unlock()
+	if cs.reqBody != nil && !cs.reqBodyClosed {
+		cs.reqBody.Close()
+		cs.reqBodyClosed = true
+		cc.cond.Broadcast()
+	}
+}
+
+type http2stickyErrWriter struct {
+	conn    net.Conn
+	timeout time.Duration
+	err     *error
+}
+
+func (sew http2stickyErrWriter) Write(p []byte) (n int, err error) {
+	if *sew.err != nil {
+		return 0, *sew.err
+	}
+	for {
+		if sew.timeout != 0 {
+			sew.conn.SetWriteDeadline(time.Now().Add(sew.timeout))
+		}
+		nn, err := sew.conn.Write(p[n:])
+		n += nn
+		if n < len(p) && nn > 0 && errors.Is(err, os.ErrDeadlineExceeded) {
+			// Keep extending the deadline so long as we're making progress.
+			continue
+		}
+		if sew.timeout != 0 {
+			sew.conn.SetWriteDeadline(time.Time{})
+		}
+		*sew.err = err
+		return n, err
+	}
+}
+
+// noCachedConnError is the concrete type of ErrNoCachedConn, which
+// needs to be detected by net/http regardless of whether it's its
+// bundled version (in h2_bundle.go with a rewritten type name) or
+// from a user's x/net/http2. As such, as it has a unique method name
+// (IsHTTP2NoCachedConnError) that net/http sniffs for via func
+// isNoCachedConnError.
+type http2noCachedConnError struct{}
+
+func (http2noCachedConnError) IsHTTP2NoCachedConnError() {}
+
+func (http2noCachedConnError) Error() string { return "http2: no cached connection was available" }
+
+// isNoCachedConnError reports whether err is of type noCachedConnError
+// or its equivalent renamed type in net/http2's h2_bundle.go. Both types
+// may coexist in the same running program.
+func http2isNoCachedConnError(err error) bool {
+	_, ok := err.(interface{ IsHTTP2NoCachedConnError() })
+	return ok
+}
+
+var http2ErrNoCachedConn error = http2noCachedConnError{}
+
+// RoundTripOpt are options for the Transport.RoundTripOpt method.
+type http2RoundTripOpt struct {
+	// OnlyCachedConn controls whether RoundTripOpt may
+	// create a new TCP connection. If set true and
+	// no cached connection is available, RoundTripOpt
+	// will return ErrNoCachedConn.
+	OnlyCachedConn bool
+}
+
+func (t *http2Transport) RoundTrip(req *Request) (*Response, error) {
+	return t.RoundTripOpt(req, http2RoundTripOpt{})
+}
+
+// authorityAddr returns a given authority (a host/IP, or host:port / ip:port)
+// and returns a host:port. The port 443 is added if needed.
+func http2authorityAddr(scheme string, authority string) (addr string) {
+	host, port, err := net.SplitHostPort(authority)
+	if err != nil { // authority didn't have a port
+		port = "443"
+		if scheme == "http" {
+			port = "80"
+		}
+		host = authority
+	}
+	if a, err := idna.ToASCII(host); err == nil {
+		host = a
+	}
+	// IPv6 address literal, without a port:
+	if strings.HasPrefix(host, "[") && strings.HasSuffix(host, "]") {
+		return host + ":" + port
+	}
+	return net.JoinHostPort(host, port)
+}
+
+// RoundTripOpt is like RoundTrip, but takes options.
+func (t *http2Transport) RoundTripOpt(req *Request, opt http2RoundTripOpt) (*Response, error) {
+	if !(req.URL.Scheme == "https" || (req.URL.Scheme == "http" && t.AllowHTTP)) {
+		return nil, errors.New("http2: unsupported scheme")
+	}
+
+	addr := http2authorityAddr(req.URL.Scheme, req.URL.Host)
+	for retry := 0; ; retry++ {
+		cc, err := t.connPool().GetClientConn(req, addr)
+		if err != nil {
+			t.vlogf("http2: Transport failed to get client conn for %s: %v", addr, err)
+			return nil, err
+		}
+		reused := !atomic.CompareAndSwapUint32(&cc.reused, 0, 1)
+		http2traceGotConn(req, cc, reused)
+		res, err := cc.RoundTrip(req)
+		if err != nil && retry <= 6 {
+			if req, err = http2shouldRetryRequest(req, err); err == nil {
+				// After the first retry, do exponential backoff with 10% jitter.
+				if retry == 0 {
+					t.vlogf("RoundTrip retrying after failure: %v", err)
+					continue
+				}
+				backoff := float64(uint(1) << (uint(retry) - 1))
+				backoff += backoff * (0.1 * mathrand.Float64())
+				select {
+				case <-time.After(time.Second * time.Duration(backoff)):
+					t.vlogf("RoundTrip retrying after failure: %v", err)
+					continue
+				case <-req.Context().Done():
+					err = req.Context().Err()
+				}
+			}
+		}
+		if err != nil {
+			t.vlogf("RoundTrip failure: %v", err)
+			return nil, err
+		}
+		return res, nil
+	}
+}
+
+// CloseIdleConnections closes any connections which were previously
+// connected from previous requests but are now sitting idle.
+// It does not interrupt any connections currently in use.
+func (t *http2Transport) CloseIdleConnections() {
+	if cp, ok := t.connPool().(http2clientConnPoolIdleCloser); ok {
+		cp.closeIdleConnections()
+	}
+}
+
+var (
+	http2errClientConnClosed    = errors.New("http2: client conn is closed")
+	http2errClientConnUnusable  = errors.New("http2: client conn not usable")
+	http2errClientConnGotGoAway = errors.New("http2: Transport received Server's graceful shutdown GOAWAY")
+)
+
+// shouldRetryRequest is called by RoundTrip when a request fails to get
+// response headers. It is always called with a non-nil error.
+// It returns either a request to retry (either the same request, or a
+// modified clone), or an error if the request can't be replayed.
+func http2shouldRetryRequest(req *Request, err error) (*Request, error) {
+	if !http2canRetryError(err) {
+		return nil, err
+	}
+	// If the Body is nil (or http.NoBody), it's safe to reuse
+	// this request and its Body.
+	if req.Body == nil || req.Body == NoBody {
+		return req, nil
+	}
+
+	// If the request body can be reset back to its original
+	// state via the optional req.GetBody, do that.
+	if req.GetBody != nil {
+		body, err := req.GetBody()
+		if err != nil {
+			return nil, err
+		}
+		newReq := *req
+		newReq.Body = body
+		return &newReq, nil
+	}
+
+	// The Request.Body can't reset back to the beginning, but we
+	// don't seem to have started to read from it yet, so reuse
+	// the request directly.
+	if err == http2errClientConnUnusable {
+		return req, nil
+	}
+
+	return nil, fmt.Errorf("http2: Transport: cannot retry err [%v] after Request.Body was written; define Request.GetBody to avoid this error", err)
+}
+
+func http2canRetryError(err error) bool {
+	if err == http2errClientConnUnusable || err == http2errClientConnGotGoAway {
+		return true
+	}
+	if se, ok := err.(http2StreamError); ok {
+		if se.Code == http2ErrCodeProtocol && se.Cause == http2errFromPeer {
+			// See golang/go#47635, golang/go#42777
+			return true
+		}
+		return se.Code == http2ErrCodeRefusedStream
+	}
+	return false
+}
+
+func (t *http2Transport) dialClientConn(ctx context.Context, addr string, singleUse bool) (*http2ClientConn, error) {
+	host, _, err := net.SplitHostPort(addr)
+	if err != nil {
+		return nil, err
+	}
+	tconn, err := t.dialTLS(ctx)("tcp", addr, t.newTLSConfig(host))
+	if err != nil {
+		return nil, err
+	}
+	return t.newClientConn(tconn, singleUse)
+}
+
+func (t *http2Transport) newTLSConfig(host string) *tls.Config {
+	cfg := new(tls.Config)
+	if t.TLSClientConfig != nil {
+		*cfg = *t.TLSClientConfig.Clone()
+	}
+	if !http2strSliceContains(cfg.NextProtos, http2NextProtoTLS) {
+		cfg.NextProtos = append([]string{http2NextProtoTLS}, cfg.NextProtos...)
+	}
+	if cfg.ServerName == "" {
+		cfg.ServerName = host
+	}
+	return cfg
+}
+
+func (t *http2Transport) dialTLS(ctx context.Context) func(string, string, *tls.Config) (net.Conn, error) {
+	if t.DialTLS != nil {
+		return t.DialTLS
+	}
+	return func(network, addr string, cfg *tls.Config) (net.Conn, error) {
+		tlsCn, err := t.dialTLSWithContext(ctx, network, addr, cfg)
+		if err != nil {
+			return nil, err
+		}
+		state := tlsCn.ConnectionState()
+		if p := state.NegotiatedProtocol; p != http2NextProtoTLS {
+			return nil, fmt.Errorf("http2: unexpected ALPN protocol %q; want %q", p, http2NextProtoTLS)
+		}
+		if !state.NegotiatedProtocolIsMutual {
+			return nil, errors.New("http2: could not negotiate protocol mutually")
+		}
+		return tlsCn, nil
+	}
+}
+
+// disableKeepAlives reports whether connections should be closed as
+// soon as possible after handling the first request.
+func (t *http2Transport) disableKeepAlives() bool {
+	return t.t1 != nil && t.t1.DisableKeepAlives
+}
+
+func (t *http2Transport) expectContinueTimeout() time.Duration {
+	if t.t1 == nil {
+		return 0
+	}
+	return t.t1.ExpectContinueTimeout
+}
+
+func (t *http2Transport) NewClientConn(c net.Conn) (*http2ClientConn, error) {
+	return t.newClientConn(c, t.disableKeepAlives())
+}
+
+func (t *http2Transport) newClientConn(c net.Conn, singleUse bool) (*http2ClientConn, error) {
+	cc := &http2ClientConn{
+		t:                     t,
+		tconn:                 c,
+		readerDone:            make(chan struct{}),
+		nextStreamID:          1,
+		maxFrameSize:          16 << 10,                         // spec default
+		initialWindowSize:     65535,                            // spec default
+		maxConcurrentStreams:  http2initialMaxConcurrentStreams, // "infinite", per spec. Use a smaller value until we have received server settings.
+		peerMaxHeaderListSize: 0xffffffffffffffff,               // "infinite", per spec. Use 2^64-1 instead.
+		streams:               make(map[uint32]*http2clientStream),
+		singleUse:             singleUse,
+		wantSettingsAck:       true,
+		pings:                 make(map[[8]byte]chan struct{}),
+		reqHeaderMu:           make(chan struct{}, 1),
+	}
+	if d := t.idleConnTimeout(); d != 0 {
+		cc.idleTimeout = d
+		cc.idleTimer = time.AfterFunc(d, cc.onIdleTimeout)
+	}
+	if http2VerboseLogs {
+		t.vlogf("http2: Transport creating client conn %p to %v", cc, c.RemoteAddr())
+	}
+
+	cc.cond = sync.NewCond(&cc.mu)
+	cc.flow.add(int32(http2initialWindowSize))
+
+	// TODO: adjust this writer size to account for frame size +
+	// MTU + crypto/tls record padding.
+	cc.bw = bufio.NewWriter(http2stickyErrWriter{
+		conn:    c,
+		timeout: t.WriteByteTimeout,
+		err:     &cc.werr,
+	})
+	cc.br = bufio.NewReader(c)
+	cc.fr = http2NewFramer(cc.bw, cc.br)
+	if t.CountError != nil {
+		cc.fr.countError = t.CountError
+	}
+	cc.fr.ReadMetaHeaders = hpack.NewDecoder(http2initialHeaderTableSize, nil)
+	cc.fr.MaxHeaderListSize = t.maxHeaderListSize()
+
+	// TODO: SetMaxDynamicTableSize, SetMaxDynamicTableSizeLimit on
+	// henc in response to SETTINGS frames?
+	cc.henc = hpack.NewEncoder(&cc.hbuf)
+
+	if t.AllowHTTP {
+		cc.nextStreamID = 3
+	}
+
+	if cs, ok := c.(http2connectionStater); ok {
+		state := cs.ConnectionState()
+		cc.tlsState = &state
+	}
+
+	initialSettings := []http2Setting{
+		{ID: http2SettingEnablePush, Val: 0},
+		{ID: http2SettingInitialWindowSize, Val: http2transportDefaultStreamFlow},
+	}
+	if max := t.maxHeaderListSize(); max != 0 {
+		initialSettings = append(initialSettings, http2Setting{ID: http2SettingMaxHeaderListSize, Val: max})
+	}
+
+	cc.bw.Write(http2clientPreface)
+	cc.fr.WriteSettings(initialSettings...)
+	cc.fr.WriteWindowUpdate(0, http2transportDefaultConnFlow)
+	cc.inflow.add(http2transportDefaultConnFlow + http2initialWindowSize)
+	cc.bw.Flush()
+	if cc.werr != nil {
+		cc.Close()
+		return nil, cc.werr
+	}
+
+	go cc.readLoop()
+	return cc, nil
+}
+
+func (cc *http2ClientConn) healthCheck() {
+	pingTimeout := cc.t.pingTimeout()
+	// We don't need to periodically ping in the health check, because the readLoop of ClientConn will
+	// trigger the healthCheck again if there is no frame received.
+	ctx, cancel := context.WithTimeout(context.Background(), pingTimeout)
+	defer cancel()
+	cc.vlogf("http2: Transport sending health check")
+	err := cc.Ping(ctx)
+	if err != nil {
+		cc.vlogf("http2: Transport health check failure: %v", err)
+		cc.closeForLostPing()
+	} else {
+		cc.vlogf("http2: Transport health check success")
+	}
+}
+
+// SetDoNotReuse marks cc as not reusable for future HTTP requests.
+func (cc *http2ClientConn) SetDoNotReuse() {
+	cc.mu.Lock()
+	defer cc.mu.Unlock()
+	cc.doNotReuse = true
+}
+
+func (cc *http2ClientConn) setGoAway(f *http2GoAwayFrame) {
+	cc.mu.Lock()
+	defer cc.mu.Unlock()
+
+	old := cc.goAway
+	cc.goAway = f
+
+	// Merge the previous and current GoAway error frames.
+	if cc.goAwayDebug == "" {
+		cc.goAwayDebug = string(f.DebugData())
+	}
+	if old != nil && old.ErrCode != http2ErrCodeNo {
+		cc.goAway.ErrCode = old.ErrCode
+	}
+	last := f.LastStreamID
+	for streamID, cs := range cc.streams {
+		if streamID > last {
+			cs.abortStreamLocked(http2errClientConnGotGoAway)
+		}
+	}
+}
+
+// CanTakeNewRequest reports whether the connection can take a new request,
+// meaning it has not been closed or received or sent a GOAWAY.
+//
+// If the caller is going to immediately make a new request on this
+// connection, use ReserveNewRequest instead.
+func (cc *http2ClientConn) CanTakeNewRequest() bool {
+	cc.mu.Lock()
+	defer cc.mu.Unlock()
+	return cc.canTakeNewRequestLocked()
+}
+
+// ReserveNewRequest is like CanTakeNewRequest but also reserves a
+// concurrent stream in cc. The reservation is decremented on the
+// next call to RoundTrip.
+func (cc *http2ClientConn) ReserveNewRequest() bool {
+	cc.mu.Lock()
+	defer cc.mu.Unlock()
+	if st := cc.idleStateLocked(); !st.canTakeNewRequest {
+		return false
+	}
+	cc.streamsReserved++
+	return true
+}
+
+// ClientConnState describes the state of a ClientConn.
+type http2ClientConnState struct {
+	// Closed is whether the connection is closed.
+	Closed bool
+
+	// Closing is whether the connection is in the process of
+	// closing. It may be closing due to shutdown, being a
+	// single-use connection, being marked as DoNotReuse, or
+	// having received a GOAWAY frame.
+	Closing bool
+
+	// StreamsActive is how many streams are active.
+	StreamsActive int
+
+	// StreamsReserved is how many streams have been reserved via
+	// ClientConn.ReserveNewRequest.
+	StreamsReserved int
+
+	// StreamsPending is how many requests have been sent in excess
+	// of the peer's advertised MaxConcurrentStreams setting and
+	// are waiting for other streams to complete.
+	StreamsPending int
+
+	// MaxConcurrentStreams is how many concurrent streams the
+	// peer advertised as acceptable. Zero means no SETTINGS
+	// frame has been received yet.
+	MaxConcurrentStreams uint32
+
+	// LastIdle, if non-zero, is when the connection last
+	// transitioned to idle state.
+	LastIdle time.Time
+}
+
+// State returns a snapshot of cc's state.
+func (cc *http2ClientConn) State() http2ClientConnState {
+	cc.wmu.Lock()
+	maxConcurrent := cc.maxConcurrentStreams
+	if !cc.seenSettings {
+		maxConcurrent = 0
+	}
+	cc.wmu.Unlock()
+
+	cc.mu.Lock()
+	defer cc.mu.Unlock()
+	return http2ClientConnState{
+		Closed:               cc.closed,
+		Closing:              cc.closing || cc.singleUse || cc.doNotReuse || cc.goAway != nil,
+		StreamsActive:        len(cc.streams),
+		StreamsReserved:      cc.streamsReserved,
+		StreamsPending:       cc.pendingRequests,
+		LastIdle:             cc.lastIdle,
+		MaxConcurrentStreams: maxConcurrent,
+	}
+}
+
+// clientConnIdleState describes the suitability of a client
+// connection to initiate a new RoundTrip request.
+type http2clientConnIdleState struct {
+	canTakeNewRequest bool
+}
+
+func (cc *http2ClientConn) idleState() http2clientConnIdleState {
+	cc.mu.Lock()
+	defer cc.mu.Unlock()
+	return cc.idleStateLocked()
+}
+
+func (cc *http2ClientConn) idleStateLocked() (st http2clientConnIdleState) {
+	if cc.singleUse && cc.nextStreamID > 1 {
+		return
+	}
+	var maxConcurrentOkay bool
+	if cc.t.StrictMaxConcurrentStreams {
+		// We'll tell the caller we can take a new request to
+		// prevent the caller from dialing a new TCP
+		// connection, but then we'll block later before
+		// writing it.
+		maxConcurrentOkay = true
+	} else {
+		maxConcurrentOkay = int64(len(cc.streams)+cc.streamsReserved+1) <= int64(cc.maxConcurrentStreams)
+	}
+
+	st.canTakeNewRequest = cc.goAway == nil && !cc.closed && !cc.closing && maxConcurrentOkay &&
+		!cc.doNotReuse &&
+		int64(cc.nextStreamID)+2*int64(cc.pendingRequests) < math.MaxInt32 &&
+		!cc.tooIdleLocked()
+	return
+}
+
+func (cc *http2ClientConn) canTakeNewRequestLocked() bool {
+	st := cc.idleStateLocked()
+	return st.canTakeNewRequest
+}
+
+// tooIdleLocked reports whether this connection has been been sitting idle
+// for too much wall time.
+func (cc *http2ClientConn) tooIdleLocked() bool {
+	// The Round(0) strips the monontonic clock reading so the
+	// times are compared based on their wall time. We don't want
+	// to reuse a connection that's been sitting idle during
+	// VM/laptop suspend if monotonic time was also frozen.
+	return cc.idleTimeout != 0 && !cc.lastIdle.IsZero() && time.Since(cc.lastIdle.Round(0)) > cc.idleTimeout
+}
+
+// onIdleTimeout is called from a time.AfterFunc goroutine. It will
+// only be called when we're idle, but because we're coming from a new
+// goroutine, there could be a new request coming in at the same time,
+// so this simply calls the synchronized closeIfIdle to shut down this
+// connection. The timer could just call closeIfIdle, but this is more
+// clear.
+func (cc *http2ClientConn) onIdleTimeout() {
+	cc.closeIfIdle()
+}
+
+func (cc *http2ClientConn) closeConn() error {
+	t := time.AfterFunc(250*time.Millisecond, cc.forceCloseConn)
+	defer t.Stop()
+	return cc.tconn.Close()
+}
+
+// A tls.Conn.Close can hang for a long time if the peer is unresponsive.
+// Try to shut it down more aggressively.
+func (cc *http2ClientConn) forceCloseConn() {
+	tc, ok := cc.tconn.(*tls.Conn)
+	if !ok {
+		return
+	}
+	if nc := http2tlsUnderlyingConn(tc); nc != nil {
+		nc.Close()
+	}
+}
+
+func (cc *http2ClientConn) closeIfIdle() {
+	cc.mu.Lock()
+	if len(cc.streams) > 0 || cc.streamsReserved > 0 {
+		cc.mu.Unlock()
+		return
+	}
+	cc.closed = true
+	nextID := cc.nextStreamID
+	// TODO: do clients send GOAWAY too? maybe? Just Close:
+	cc.mu.Unlock()
+
+	if http2VerboseLogs {
+		cc.vlogf("http2: Transport closing idle conn %p (forSingleUse=%v, maxStream=%v)", cc, cc.singleUse, nextID-2)
+	}
+	cc.closeConn()
+}
+
+func (cc *http2ClientConn) isDoNotReuseAndIdle() bool {
+	cc.mu.Lock()
+	defer cc.mu.Unlock()
+	return cc.doNotReuse && len(cc.streams) == 0
+}
+
+var http2shutdownEnterWaitStateHook = func() {}
+
+// Shutdown gracefully closes the client connection, waiting for running streams to complete.
+func (cc *http2ClientConn) Shutdown(ctx context.Context) error {
+	if err := cc.sendGoAway(); err != nil {
+		return err
+	}
+	// Wait for all in-flight streams to complete or connection to close
+	done := make(chan struct{})
+	cancelled := false // guarded by cc.mu
+	go func() {
+		cc.mu.Lock()
+		defer cc.mu.Unlock()
+		for {
+			if len(cc.streams) == 0 || cc.closed {
+				cc.closed = true
+				close(done)
+				break
+			}
+			if cancelled {
+				break
+			}
+			cc.cond.Wait()
+		}
+	}()
+	http2shutdownEnterWaitStateHook()
+	select {
+	case <-done:
+		return cc.closeConn()
+	case <-ctx.Done():
+		cc.mu.Lock()
+		// Free the goroutine above
+		cancelled = true
+		cc.cond.Broadcast()
+		cc.mu.Unlock()
+		return ctx.Err()
+	}
+}
+
+func (cc *http2ClientConn) sendGoAway() error {
+	cc.mu.Lock()
+	closing := cc.closing
+	cc.closing = true
+	maxStreamID := cc.nextStreamID
+	cc.mu.Unlock()
+	if closing {
+		// GOAWAY sent already
+		return nil
+	}
+
+	cc.wmu.Lock()
+	defer cc.wmu.Unlock()
+	// Send a graceful shutdown frame to server
+	if err := cc.fr.WriteGoAway(maxStreamID, http2ErrCodeNo, nil); err != nil {
+		return err
+	}
+	if err := cc.bw.Flush(); err != nil {
+		return err
+	}
+	// Prevent new requests
+	return nil
+}
+
+// closes the client connection immediately. In-flight requests are interrupted.
+// err is sent to streams.
+func (cc *http2ClientConn) closeForError(err error) error {
+	cc.mu.Lock()
+	cc.closed = true
+	for _, cs := range cc.streams {
+		cs.abortStreamLocked(err)
+	}
+	cc.cond.Broadcast()
+	cc.mu.Unlock()
+	return cc.closeConn()
+}
+
+// Close closes the client connection immediately.
+//
+// In-flight requests are interrupted. For a graceful shutdown, use Shutdown instead.
+func (cc *http2ClientConn) Close() error {
+	err := errors.New("http2: client connection force closed via ClientConn.Close")
+	return cc.closeForError(err)
+}
+
+// closes the client connection immediately. In-flight requests are interrupted.
+func (cc *http2ClientConn) closeForLostPing() error {
+	err := errors.New("http2: client connection lost")
+	if f := cc.t.CountError; f != nil {
+		f("conn_close_lost_ping")
+	}
+	return cc.closeForError(err)
+}
+
+// errRequestCanceled is a copy of net/http's errRequestCanceled because it's not
+// exported. At least they'll be DeepEqual for h1-vs-h2 comparisons tests.
+var http2errRequestCanceled = errors.New("net/http: request canceled")
+
+func http2commaSeparatedTrailers(req *Request) (string, error) {
+	keys := make([]string, 0, len(req.Trailer))
+	for k := range req.Trailer {
+		k = CanonicalHeaderKey(k)
+		switch k {
+		case "Transfer-Encoding", "Trailer", "Content-Length":
+			return "", fmt.Errorf("invalid Trailer key %q", k)
+		}
+		keys = append(keys, k)
+	}
+	if len(keys) > 0 {
+		sort.Strings(keys)
+		return strings.Join(keys, ","), nil
+	}
+	return "", nil
+}
+
+func (cc *http2ClientConn) responseHeaderTimeout() time.Duration {
+	if cc.t.t1 != nil {
+		return cc.t.t1.ResponseHeaderTimeout
+	}
+	// No way to do this (yet?) with just an http2.Transport. Probably
+	// no need. Request.Cancel this is the new way. We only need to support
+	// this for compatibility with the old http.Transport fields when
+	// we're doing transparent http2.
+	return 0
+}
+
+// checkConnHeaders checks whether req has any invalid connection-level headers.
+// per RFC 7540 section 8.1.2.2: Connection-Specific Header Fields.
+// Certain headers are special-cased as okay but not transmitted later.
+func http2checkConnHeaders(req *Request) error {
+	if v := req.Header.Get("Upgrade"); v != "" {
+		return fmt.Errorf("http2: invalid Upgrade request header: %q", req.Header["Upgrade"])
+	}
+	if vv := req.Header["Transfer-Encoding"]; len(vv) > 0 && (len(vv) > 1 || vv[0] != "" && vv[0] != "chunked") {
+		return fmt.Errorf("http2: invalid Transfer-Encoding request header: %q", vv)
+	}
+	if vv := req.Header["Connection"]; len(vv) > 0 && (len(vv) > 1 || vv[0] != "" && !http2asciiEqualFold(vv[0], "close") && !http2asciiEqualFold(vv[0], "keep-alive")) {
+		return fmt.Errorf("http2: invalid Connection request header: %q", vv)
+	}
+	return nil
+}
+
+// actualContentLength returns a sanitized version of
+// req.ContentLength, where 0 actually means zero (not unknown) and -1
+// means unknown.
+func http2actualContentLength(req *Request) int64 {
+	if req.Body == nil || req.Body == NoBody {
+		return 0
+	}
+	if req.ContentLength != 0 {
+		return req.ContentLength
+	}
+	return -1
+}
+
+func (cc *http2ClientConn) decrStreamReservations() {
+	cc.mu.Lock()
+	defer cc.mu.Unlock()
+	cc.decrStreamReservationsLocked()
+}
+
+func (cc *http2ClientConn) decrStreamReservationsLocked() {
+	if cc.streamsReserved > 0 {
+		cc.streamsReserved--
+	}
+}
+
+func (cc *http2ClientConn) RoundTrip(req *Request) (*Response, error) {
+	ctx := req.Context()
+	cs := &http2clientStream{
+		cc:                   cc,
+		ctx:                  ctx,
+		reqCancel:            req.Cancel,
+		isHead:               req.Method == "HEAD",
+		reqBody:              req.Body,
+		reqBodyContentLength: http2actualContentLength(req),
+		trace:                httptrace.ContextClientTrace(ctx),
+		peerClosed:           make(chan struct{}),
+		abort:                make(chan struct{}),
+		respHeaderRecv:       make(chan struct{}),
+		donec:                make(chan struct{}),
+	}
+	go cs.doRequest(req)
+
+	waitDone := func() error {
+		select {
+		case <-cs.donec:
+			return nil
+		case <-ctx.Done():
+			return ctx.Err()
+		case <-cs.reqCancel:
+			return http2errRequestCanceled
+		}
+	}
+
+	handleResponseHeaders := func() (*Response, error) {
+		res := cs.res
+		if res.StatusCode > 299 {
+			// On error or status code 3xx, 4xx, 5xx, etc abort any
+			// ongoing write, assuming that the server doesn't care
+			// about our request body. If the server replied with 1xx or
+			// 2xx, however, then assume the server DOES potentially
+			// want our body (e.g. full-duplex streaming:
+			// golang.org/issue/13444). If it turns out the server
+			// doesn't, they'll RST_STREAM us soon enough. This is a
+			// heuristic to avoid adding knobs to Transport. Hopefully
+			// we can keep it.
+			cs.abortRequestBodyWrite()
+		}
+		res.Request = req
+		res.TLS = cc.tlsState
+		if res.Body == http2noBody && http2actualContentLength(req) == 0 {
+			// If there isn't a request or response body still being
+			// written, then wait for the stream to be closed before
+			// RoundTrip returns.
+			if err := waitDone(); err != nil {
+				return nil, err
+			}
+		}
+		return res, nil
+	}
+
+	for {
+		select {
+		case <-cs.respHeaderRecv:
+			return handleResponseHeaders()
+		case <-cs.abort:
+			select {
+			case <-cs.respHeaderRecv:
+				// If both cs.respHeaderRecv and cs.abort are signaling,
+				// pick respHeaderRecv. The server probably wrote the
+				// response and immediately reset the stream.
+				// golang.org/issue/49645
+				return handleResponseHeaders()
+			default:
+				waitDone()
+				return nil, cs.abortErr
+			}
+		case <-ctx.Done():
+			err := ctx.Err()
+			cs.abortStream(err)
+			return nil, err
+		case <-cs.reqCancel:
+			cs.abortStream(http2errRequestCanceled)
+			return nil, http2errRequestCanceled
+		}
+	}
+}
+
+// doRequest runs for the duration of the request lifetime.
+//
+// It sends the request and performs post-request cleanup (closing Request.Body, etc.).
+func (cs *http2clientStream) doRequest(req *Request) {
+	err := cs.writeRequest(req)
+	cs.cleanupWriteRequest(err)
+}
+
+// writeRequest sends a request.
+//
+// It returns nil after the request is written, the response read,
+// and the request stream is half-closed by the peer.
+//
+// It returns non-nil if the request ends otherwise.
+// If the returned error is StreamError, the error Code may be used in resetting the stream.
+func (cs *http2clientStream) writeRequest(req *Request) (err error) {
+	cc := cs.cc
+	ctx := cs.ctx
+
+	if err := http2checkConnHeaders(req); err != nil {
+		return err
+	}
+
+	// Acquire the new-request lock by writing to reqHeaderMu.
+	// This lock guards the critical section covering allocating a new stream ID
+	// (requires mu) and creating the stream (requires wmu).
+	if cc.reqHeaderMu == nil {
+		panic("RoundTrip on uninitialized ClientConn") // for tests
+	}
+	select {
+	case cc.reqHeaderMu <- struct{}{}:
+	case <-cs.reqCancel:
+		return http2errRequestCanceled
+	case <-ctx.Done():
+		return ctx.Err()
+	}
+
+	cc.mu.Lock()
+	if cc.idleTimer != nil {
+		cc.idleTimer.Stop()
+	}
+	cc.decrStreamReservationsLocked()
+	if err := cc.awaitOpenSlotForStreamLocked(cs); err != nil {
+		cc.mu.Unlock()
+		<-cc.reqHeaderMu
+		return err
+	}
+	cc.addStreamLocked(cs) // assigns stream ID
+	if http2isConnectionCloseRequest(req) {
+		cc.doNotReuse = true
+	}
+	cc.mu.Unlock()
+
+	// TODO(bradfitz): this is a copy of the logic in net/http. Unify somewhere?
+	if !cc.t.disableCompression() &&
+		req.Header.Get("Accept-Encoding") == "" &&
+		req.Header.Get("Range") == "" &&
+		!cs.isHead {
+		// Request gzip only, not deflate. Deflate is ambiguous and
+		// not as universally supported anyway.
+		// See: https://zlib.net/zlib_faq.html#faq39
+		//
+		// Note that we don't request this for HEAD requests,
+		// due to a bug in nginx:
+		//   http://trac.nginx.org/nginx/ticket/358
+		//   https://golang.org/issue/5522
+		//
+		// We don't request gzip if the request is for a range, since
+		// auto-decoding a portion of a gzipped document will just fail
+		// anyway. See https://golang.org/issue/8923
+		cs.requestedGzip = true
+	}
+
+	continueTimeout := cc.t.expectContinueTimeout()
+	if continueTimeout != 0 {
+		if !httpguts.HeaderValuesContainsToken(req.Header["Expect"], "100-continue") {
+			continueTimeout = 0
+		} else {
+			cs.on100 = make(chan struct{}, 1)
+		}
+	}
+
+	// Past this point (where we send request headers), it is possible for
+	// RoundTrip to return successfully. Since the RoundTrip contract permits
+	// the caller to "mutate or reuse" the Request after closing the Response's Body,
+	// we must take care when referencing the Request from here on.
+	err = cs.encodeAndWriteHeaders(req)
+	<-cc.reqHeaderMu
+	if err != nil {
+		return err
+	}
+
+	hasBody := cs.reqBodyContentLength != 0
+	if !hasBody {
+		cs.sentEndStream = true
+	} else {
+		if continueTimeout != 0 {
+			http2traceWait100Continue(cs.trace)
+			timer := time.NewTimer(continueTimeout)
+			select {
+			case <-timer.C:
+				err = nil
+			case <-cs.on100:
+				err = nil
+			case <-cs.abort:
+				err = cs.abortErr
+			case <-ctx.Done():
+				err = ctx.Err()
+			case <-cs.reqCancel:
+				err = http2errRequestCanceled
+			}
+			timer.Stop()
+			if err != nil {
+				http2traceWroteRequest(cs.trace, err)
+				return err
+			}
+		}
+
+		if err = cs.writeRequestBody(req); err != nil {
+			if err != http2errStopReqBodyWrite {
+				http2traceWroteRequest(cs.trace, err)
+				return err
+			}
+		} else {
+			cs.sentEndStream = true
+		}
+	}
+
+	http2traceWroteRequest(cs.trace, err)
+
+	var respHeaderTimer <-chan time.Time
+	var respHeaderRecv chan struct{}
+	if d := cc.responseHeaderTimeout(); d != 0 {
+		timer := time.NewTimer(d)
+		defer timer.Stop()
+		respHeaderTimer = timer.C
+		respHeaderRecv = cs.respHeaderRecv
+	}
+	// Wait until the peer half-closes its end of the stream,
+	// or until the request is aborted (via context, error, or otherwise),
+	// whichever comes first.
+	for {
+		select {
+		case <-cs.peerClosed:
+			return nil
+		case <-respHeaderTimer:
+			return http2errTimeout
+		case <-respHeaderRecv:
+			respHeaderRecv = nil
+			respHeaderTimer = nil // keep waiting for END_STREAM
+		case <-cs.abort:
+			return cs.abortErr
+		case <-ctx.Done():
+			return ctx.Err()
+		case <-cs.reqCancel:
+			return http2errRequestCanceled
+		}
+	}
+}
+
+func (cs *http2clientStream) encodeAndWriteHeaders(req *Request) error {
+	cc := cs.cc
+	ctx := cs.ctx
+
+	cc.wmu.Lock()
+	defer cc.wmu.Unlock()
+
+	// If the request was canceled while waiting for cc.mu, just quit.
+	select {
+	case <-cs.abort:
+		return cs.abortErr
+	case <-ctx.Done():
+		return ctx.Err()
+	case <-cs.reqCancel:
+		return http2errRequestCanceled
+	default:
+	}
+
+	// Encode headers.
+	//
+	// we send: HEADERS{1}, CONTINUATION{0,} + DATA{0,} (DATA is
+	// sent by writeRequestBody below, along with any Trailers,
+	// again in form HEADERS{1}, CONTINUATION{0,})
+	trailers, err := http2commaSeparatedTrailers(req)
+	if err != nil {
+		return err
+	}
+	hasTrailers := trailers != ""
+	contentLen := http2actualContentLength(req)
+	hasBody := contentLen != 0
+	hdrs, err := cc.encodeHeaders(req, cs.requestedGzip, trailers, contentLen)
+	if err != nil {
+		return err
+	}
+
+	// Write the request.
+	endStream := !hasBody && !hasTrailers
+	cs.sentHeaders = true
+	err = cc.writeHeaders(cs.ID, endStream, int(cc.maxFrameSize), hdrs)
+	http2traceWroteHeaders(cs.trace)
+	return err
+}
+
+// cleanupWriteRequest performs post-request tasks.
+//
+// If err (the result of writeRequest) is non-nil and the stream is not closed,
+// cleanupWriteRequest will send a reset to the peer.
+func (cs *http2clientStream) cleanupWriteRequest(err error) {
+	cc := cs.cc
+
+	if cs.ID == 0 {
+		// We were canceled before creating the stream, so return our reservation.
+		cc.decrStreamReservations()
+	}
+
+	// TODO: write h12Compare test showing whether
+	// Request.Body is closed by the Transport,
+	// and in multiple cases: server replies <=299 and >299
+	// while still writing request body
+	cc.mu.Lock()
+	bodyClosed := cs.reqBodyClosed
+	cs.reqBodyClosed = true
+	cc.mu.Unlock()
+	if !bodyClosed && cs.reqBody != nil {
+		cs.reqBody.Close()
+	}
+
+	if err != nil && cs.sentEndStream {
+		// If the connection is closed immediately after the response is read,
+		// we may be aborted before finishing up here. If the stream was closed
+		// cleanly on both sides, there is no error.
+		select {
+		case <-cs.peerClosed:
+			err = nil
+		default:
+		}
+	}
+	if err != nil {
+		cs.abortStream(err) // possibly redundant, but harmless
+		if cs.sentHeaders {
+			if se, ok := err.(http2StreamError); ok {
+				if se.Cause != http2errFromPeer {
+					cc.writeStreamReset(cs.ID, se.Code, err)
+				}
+			} else {
+				cc.writeStreamReset(cs.ID, http2ErrCodeCancel, err)
+			}
+		}
+		cs.bufPipe.CloseWithError(err) // no-op if already closed
+	} else {
+		if cs.sentHeaders && !cs.sentEndStream {
+			cc.writeStreamReset(cs.ID, http2ErrCodeNo, nil)
+		}
+		cs.bufPipe.CloseWithError(http2errRequestCanceled)
+	}
+	if cs.ID != 0 {
+		cc.forgetStreamID(cs.ID)
+	}
+
+	cc.wmu.Lock()
+	werr := cc.werr
+	cc.wmu.Unlock()
+	if werr != nil {
+		cc.Close()
+	}
+
+	close(cs.donec)
+}
+
+// awaitOpenSlotForStream waits until len(streams) < maxConcurrentStreams.
+// Must hold cc.mu.
+func (cc *http2ClientConn) awaitOpenSlotForStreamLocked(cs *http2clientStream) error {
+	for {
+		cc.lastActive = time.Now()
+		if cc.closed || !cc.canTakeNewRequestLocked() {
+			return http2errClientConnUnusable
+		}
+		cc.lastIdle = time.Time{}
+		if int64(len(cc.streams)) < int64(cc.maxConcurrentStreams) {
+			return nil
+		}
+		cc.pendingRequests++
+		cc.cond.Wait()
+		cc.pendingRequests--
+		select {
+		case <-cs.abort:
+			return cs.abortErr
+		default:
+		}
+	}
+}
+
+// requires cc.wmu be held
+func (cc *http2ClientConn) writeHeaders(streamID uint32, endStream bool, maxFrameSize int, hdrs []byte) error {
+	first := true // first frame written (HEADERS is first, then CONTINUATION)
+	for len(hdrs) > 0 && cc.werr == nil {
+		chunk := hdrs
+		if len(chunk) > maxFrameSize {
+			chunk = chunk[:maxFrameSize]
+		}
+		hdrs = hdrs[len(chunk):]
+		endHeaders := len(hdrs) == 0
+		if first {
+			cc.fr.WriteHeaders(http2HeadersFrameParam{
+				StreamID:      streamID,
+				BlockFragment: chunk,
+				EndStream:     endStream,
+				EndHeaders:    endHeaders,
+			})
+			first = false
+		} else {
+			cc.fr.WriteContinuation(streamID, endHeaders, chunk)
+		}
+	}
+	cc.bw.Flush()
+	return cc.werr
+}
+
+// internal error values; they don't escape to callers
+var (
+	// abort request body write; don't send cancel
+	http2errStopReqBodyWrite = errors.New("http2: aborting request body write")
+
+	// abort request body write, but send stream reset of cancel.
+	http2errStopReqBodyWriteAndCancel = errors.New("http2: canceling request")
+
+	http2errReqBodyTooLong = errors.New("http2: request body larger than specified content length")
+)
+
+// frameScratchBufferLen returns the length of a buffer to use for
+// outgoing request bodies to read/write to/from.
+//
+// It returns max(1, min(peer's advertised max frame size,
+// Request.ContentLength+1, 512KB)).
+func (cs *http2clientStream) frameScratchBufferLen(maxFrameSize int) int {
+	const max = 512 << 10
+	n := int64(maxFrameSize)
+	if n > max {
+		n = max
+	}
+	if cl := cs.reqBodyContentLength; cl != -1 && cl+1 < n {
+		// Add an extra byte past the declared content-length to
+		// give the caller's Request.Body io.Reader a chance to
+		// give us more bytes than they declared, so we can catch it
+		// early.
+		n = cl + 1
+	}
+	if n < 1 {
+		return 1
+	}
+	return int(n) // doesn't truncate; max is 512K
+}
+
+var http2bufPool sync.Pool // of *[]byte
+
+func (cs *http2clientStream) writeRequestBody(req *Request) (err error) {
+	cc := cs.cc
+	body := cs.reqBody
+	sentEnd := false // whether we sent the final DATA frame w/ END_STREAM
+
+	hasTrailers := req.Trailer != nil
+	remainLen := cs.reqBodyContentLength
+	hasContentLen := remainLen != -1
+
+	cc.mu.Lock()
+	maxFrameSize := int(cc.maxFrameSize)
+	cc.mu.Unlock()
+
+	// Scratch buffer for reading into & writing from.
+	scratchLen := cs.frameScratchBufferLen(maxFrameSize)
+	var buf []byte
+	if bp, ok := http2bufPool.Get().(*[]byte); ok && len(*bp) >= scratchLen {
+		defer http2bufPool.Put(bp)
+		buf = *bp
+	} else {
+		buf = make([]byte, scratchLen)
+		defer http2bufPool.Put(&buf)
+	}
+
+	var sawEOF bool
+	for !sawEOF {
+		n, err := body.Read(buf[:len(buf)])
+		if hasContentLen {
+			remainLen -= int64(n)
+			if remainLen == 0 && err == nil {
+				// The request body's Content-Length was predeclared and
+				// we just finished reading it all, but the underlying io.Reader
+				// returned the final chunk with a nil error (which is one of
+				// the two valid things a Reader can do at EOF). Because we'd prefer
+				// to send the END_STREAM bit early, double-check that we're actually
+				// at EOF. Subsequent reads should return (0, EOF) at this point.
+				// If either value is different, we return an error in one of two ways below.
+				var scratch [1]byte
+				var n1 int
+				n1, err = body.Read(scratch[:])
+				remainLen -= int64(n1)
+			}
+			if remainLen < 0 {
+				err = http2errReqBodyTooLong
+				return err
+			}
+		}
+		if err != nil {
+			cc.mu.Lock()
+			bodyClosed := cs.reqBodyClosed
+			cc.mu.Unlock()
+			switch {
+			case bodyClosed:
+				return http2errStopReqBodyWrite
+			case err == io.EOF:
+				sawEOF = true
+				err = nil
+			default:
+				return err
+			}
+		}
+
+		remain := buf[:n]
+		for len(remain) > 0 && err == nil {
+			var allowed int32
+			allowed, err = cs.awaitFlowControl(len(remain))
+			if err != nil {
+				return err
+			}
+			cc.wmu.Lock()
+			data := remain[:allowed]
+			remain = remain[allowed:]
+			sentEnd = sawEOF && len(remain) == 0 && !hasTrailers
+			err = cc.fr.WriteData(cs.ID, sentEnd, data)
+			if err == nil {
+				// TODO(bradfitz): this flush is for latency, not bandwidth.
+				// Most requests won't need this. Make this opt-in or
+				// opt-out?  Use some heuristic on the body type? Nagel-like
+				// timers?  Based on 'n'? Only last chunk of this for loop,
+				// unless flow control tokens are low? For now, always.
+				// If we change this, see comment below.
+				err = cc.bw.Flush()
+			}
+			cc.wmu.Unlock()
+		}
+		if err != nil {
+			return err
+		}
+	}
+
+	if sentEnd {
+		// Already sent END_STREAM (which implies we have no
+		// trailers) and flushed, because currently all
+		// WriteData frames above get a flush. So we're done.
+		return nil
+	}
+
+	// Since the RoundTrip contract permits the caller to "mutate or reuse"
+	// a request after the Response's Body is closed, verify that this hasn't
+	// happened before accessing the trailers.
+	cc.mu.Lock()
+	trailer := req.Trailer
+	err = cs.abortErr
+	cc.mu.Unlock()
+	if err != nil {
+		return err
+	}
+
+	cc.wmu.Lock()
+	defer cc.wmu.Unlock()
+	var trls []byte
+	if len(trailer) > 0 {
+		trls, err = cc.encodeTrailers(trailer)
+		if err != nil {
+			return err
+		}
+	}
+
+	// Two ways to send END_STREAM: either with trailers, or
+	// with an empty DATA frame.
+	if len(trls) > 0 {
+		err = cc.writeHeaders(cs.ID, true, maxFrameSize, trls)
+	} else {
+		err = cc.fr.WriteData(cs.ID, true, nil)
+	}
+	if ferr := cc.bw.Flush(); ferr != nil && err == nil {
+		err = ferr
+	}
+	return err
+}
+
+// awaitFlowControl waits for [1, min(maxBytes, cc.cs.maxFrameSize)] flow
+// control tokens from the server.
+// It returns either the non-zero number of tokens taken or an error
+// if the stream is dead.
+func (cs *http2clientStream) awaitFlowControl(maxBytes int) (taken int32, err error) {
+	cc := cs.cc
+	ctx := cs.ctx
+	cc.mu.Lock()
+	defer cc.mu.Unlock()
+	for {
+		if cc.closed {
+			return 0, http2errClientConnClosed
+		}
+		if cs.reqBodyClosed {
+			return 0, http2errStopReqBodyWrite
+		}
+		select {
+		case <-cs.abort:
+			return 0, cs.abortErr
+		case <-ctx.Done():
+			return 0, ctx.Err()
+		case <-cs.reqCancel:
+			return 0, http2errRequestCanceled
+		default:
+		}
+		if a := cs.flow.available(); a > 0 {
+			take := a
+			if int(take) > maxBytes {
+
+				take = int32(maxBytes) // can't truncate int; take is int32
+			}
+			if take > int32(cc.maxFrameSize) {
+				take = int32(cc.maxFrameSize)
+			}
+			cs.flow.take(take)
+			return take, nil
+		}
+		cc.cond.Wait()
+	}
+}
+
+var http2errNilRequestURL = errors.New("http2: Request.URI is nil")
+
+// requires cc.wmu be held.
+func (cc *http2ClientConn) encodeHeaders(req *Request, addGzipHeader bool, trailers string, contentLength int64) ([]byte, error) {
+	cc.hbuf.Reset()
+	if req.URL == nil {
+		return nil, http2errNilRequestURL
+	}
+
+	host := req.Host
+	if host == "" {
+		host = req.URL.Host
+	}
+	host, err := httpguts.PunycodeHostPort(host)
+	if err != nil {
+		return nil, err
+	}
+
+	var path string
+	if req.Method != "CONNECT" {
+		path = req.URL.RequestURI()
+		if !http2validPseudoPath(path) {
+			orig := path
+			path = strings.TrimPrefix(path, req.URL.Scheme+"://"+host)
+			if !http2validPseudoPath(path) {
+				if req.URL.Opaque != "" {
+					return nil, fmt.Errorf("invalid request :path %q from URL.Opaque = %q", orig, req.URL.Opaque)
+				} else {
+					return nil, fmt.Errorf("invalid request :path %q", orig)
+				}
+			}
+		}
+	}
+
+	// Check for any invalid headers and return an error before we
+	// potentially pollute our hpack state. (We want to be able to
+	// continue to reuse the hpack encoder for future requests)
+	for k, vv := range req.Header {
+		if !httpguts.ValidHeaderFieldName(k) {
+			return nil, fmt.Errorf("invalid HTTP header name %q", k)
+		}
+		for _, v := range vv {
+			if !httpguts.ValidHeaderFieldValue(v) {
+				// Don't include the value in the error, because it may be sensitive.
+				return nil, fmt.Errorf("invalid HTTP header value for header %q", k)
+			}
+		}
+	}
+
+	enumerateHeaders := func(f func(name, value string)) {
+		// 8.1.2.3 Request Pseudo-Header Fields
+		// The :path pseudo-header field includes the path and query parts of the
+		// target URI (the path-absolute production and optionally a '?' character
+		// followed by the query production (see Sections 3.3 and 3.4 of
+		// [RFC3986]).
+		f(":authority", host)
+		m := req.Method
+		if m == "" {
+			m = MethodGet
+		}
+		f(":method", m)
+		if req.Method != "CONNECT" {
+			f(":path", path)
+			f(":scheme", req.URL.Scheme)
+		}
+		if trailers != "" {
+			f("trailer", trailers)
+		}
+
+		var didUA bool
+		for k, vv := range req.Header {
+			if http2asciiEqualFold(k, "host") || http2asciiEqualFold(k, "content-length") {
+				// Host is :authority, already sent.
+				// Content-Length is automatic, set below.
+				continue
+			} else if http2asciiEqualFold(k, "connection") ||
+				http2asciiEqualFold(k, "proxy-connection") ||
+				http2asciiEqualFold(k, "transfer-encoding") ||
+				http2asciiEqualFold(k, "upgrade") ||
+				http2asciiEqualFold(k, "keep-alive") {
+				// Per 8.1.2.2 Connection-Specific Header
+				// Fields, don't send connection-specific
+				// fields. We have already checked if any
+				// are error-worthy so just ignore the rest.
+				continue
+			} else if http2asciiEqualFold(k, "user-agent") {
+				// Match Go's http1 behavior: at most one
+				// User-Agent. If set to nil or empty string,
+				// then omit it. Otherwise if not mentioned,
+				// include the default (below).
+				didUA = true
+				if len(vv) < 1 {
+					continue
+				}
+				vv = vv[:1]
+				if vv[0] == "" {
+					continue
+				}
+			} else if http2asciiEqualFold(k, "cookie") {
+				// Per 8.1.2.5 To allow for better compression efficiency, the
+				// Cookie header field MAY be split into separate header fields,
+				// each with one or more cookie-pairs.
+				for _, v := range vv {
+					for {
+						p := strings.IndexByte(v, ';')
+						if p < 0 {
+							break
+						}
+						f("cookie", v[:p])
+						p++
+						// strip space after semicolon if any.
+						for p+1 <= len(v) && v[p] == ' ' {
+							p++
+						}
+						v = v[p:]
+					}
+					if len(v) > 0 {
+						f("cookie", v)
+					}
+				}
+				continue
+			}
+
+			for _, v := range vv {
+				f(k, v)
+			}
+		}
+		if http2shouldSendReqContentLength(req.Method, contentLength) {
+			f("content-length", strconv.FormatInt(contentLength, 10))
+		}
+		if addGzipHeader {
+			f("accept-encoding", "gzip")
+		}
+		if !didUA {
+			f("user-agent", http2defaultUserAgent)
+		}
+	}
+
+	// Do a first pass over the headers counting bytes to ensure
+	// we don't exceed cc.peerMaxHeaderListSize. This is done as a
+	// separate pass before encoding the headers to prevent
+	// modifying the hpack state.
+	hlSize := uint64(0)
+	enumerateHeaders(func(name, value string) {
+		hf := hpack.HeaderField{Name: name, Value: value}
+		hlSize += uint64(hf.Size())
+	})
+
+	if hlSize > cc.peerMaxHeaderListSize {
+		return nil, http2errRequestHeaderListSize
+	}
+
+	trace := httptrace.ContextClientTrace(req.Context())
+	traceHeaders := http2traceHasWroteHeaderField(trace)
+
+	// Header list size is ok. Write the headers.
+	enumerateHeaders(func(name, value string) {
+		name, ascii := http2asciiToLower(name)
+		if !ascii {
+			// Skip writing invalid headers. Per RFC 7540, Section 8.1.2, header
+			// field names have to be ASCII characters (just as in HTTP/1.x).
+			return
+		}
+		cc.writeHeader(name, value)
+		if traceHeaders {
+			http2traceWroteHeaderField(trace, name, value)
+		}
+	})
+
+	return cc.hbuf.Bytes(), nil
+}
+
+// shouldSendReqContentLength reports whether the http2.Transport should send
+// a "content-length" request header. This logic is basically a copy of the net/http
+// transferWriter.shouldSendContentLength.
+// The contentLength is the corrected contentLength (so 0 means actually 0, not unknown).
+// -1 means unknown.
+func http2shouldSendReqContentLength(method string, contentLength int64) bool {
+	if contentLength > 0 {
+		return true
+	}
+	if contentLength < 0 {
+		return false
+	}
+	// For zero bodies, whether we send a content-length depends on the method.
+	// It also kinda doesn't matter for http2 either way, with END_STREAM.
+	switch method {
+	case "POST", "PUT", "PATCH":
+		return true
+	default:
+		return false
+	}
+}
+
+// requires cc.wmu be held.
+func (cc *http2ClientConn) encodeTrailers(trailer Header) ([]byte, error) {
+	cc.hbuf.Reset()
+
+	hlSize := uint64(0)
+	for k, vv := range trailer {
+		for _, v := range vv {
+			hf := hpack.HeaderField{Name: k, Value: v}
+			hlSize += uint64(hf.Size())
+		}
+	}
+	if hlSize > cc.peerMaxHeaderListSize {
+		return nil, http2errRequestHeaderListSize
+	}
+
+	for k, vv := range trailer {
+		lowKey, ascii := http2asciiToLower(k)
+		if !ascii {
+			// Skip writing invalid headers. Per RFC 7540, Section 8.1.2, header
+			// field names have to be ASCII characters (just as in HTTP/1.x).
+			continue
+		}
+		// Transfer-Encoding, etc.. have already been filtered at the
+		// start of RoundTrip
+		for _, v := range vv {
+			cc.writeHeader(lowKey, v)
+		}
+	}
+	return cc.hbuf.Bytes(), nil
+}
+
+func (cc *http2ClientConn) writeHeader(name, value string) {
+	if http2VerboseLogs {
+		log.Printf("http2: Transport encoding header %q = %q", name, value)
+	}
+	cc.henc.WriteField(hpack.HeaderField{Name: name, Value: value})
+}
+
+type http2resAndError struct {
+	_   http2incomparable
+	res *Response
+	err error
+}
+
+// requires cc.mu be held.
+func (cc *http2ClientConn) addStreamLocked(cs *http2clientStream) {
+	cs.flow.add(int32(cc.initialWindowSize))
+	cs.flow.setConnFlow(&cc.flow)
+	cs.inflow.add(http2transportDefaultStreamFlow)
+	cs.inflow.setConnFlow(&cc.inflow)
+	cs.ID = cc.nextStreamID
+	cc.nextStreamID += 2
+	cc.streams[cs.ID] = cs
+	if cs.ID == 0 {
+		panic("assigned stream ID 0")
+	}
+}
+
+func (cc *http2ClientConn) forgetStreamID(id uint32) {
+	cc.mu.Lock()
+	slen := len(cc.streams)
+	delete(cc.streams, id)
+	if len(cc.streams) != slen-1 {
+		panic("forgetting unknown stream id")
+	}
+	cc.lastActive = time.Now()
+	if len(cc.streams) == 0 && cc.idleTimer != nil {
+		cc.idleTimer.Reset(cc.idleTimeout)
+		cc.lastIdle = time.Now()
+	}
+	// Wake up writeRequestBody via clientStream.awaitFlowControl and
+	// wake up RoundTrip if there is a pending request.
+	cc.cond.Broadcast()
+
+	closeOnIdle := cc.singleUse || cc.doNotReuse || cc.t.disableKeepAlives()
+	if closeOnIdle && cc.streamsReserved == 0 && len(cc.streams) == 0 {
+		if http2VerboseLogs {
+			cc.vlogf("http2: Transport closing idle conn %p (forSingleUse=%v, maxStream=%v)", cc, cc.singleUse, cc.nextStreamID-2)
+		}
+		cc.closed = true
+		defer cc.closeConn()
+	}
+
+	cc.mu.Unlock()
+}
+
+// clientConnReadLoop is the state owned by the clientConn's frame-reading readLoop.
+type http2clientConnReadLoop struct {
+	_  http2incomparable
+	cc *http2ClientConn
+}
+
+// readLoop runs in its own goroutine and reads and dispatches frames.
+func (cc *http2ClientConn) readLoop() {
+	rl := &http2clientConnReadLoop{cc: cc}
+	defer rl.cleanup()
+	cc.readerErr = rl.run()
+	if ce, ok := cc.readerErr.(http2ConnectionError); ok {
+		cc.wmu.Lock()
+		cc.fr.WriteGoAway(0, http2ErrCode(ce), nil)
+		cc.wmu.Unlock()
+	}
+}
+
+// GoAwayError is returned by the Transport when the server closes the
+// TCP connection after sending a GOAWAY frame.
+type http2GoAwayError struct {
+	LastStreamID uint32
+	ErrCode      http2ErrCode
+	DebugData    string
+}
+
+func (e http2GoAwayError) Error() string {
+	return fmt.Sprintf("http2: server sent GOAWAY and closed the connection; LastStreamID=%v, ErrCode=%v, debug=%q",
+		e.LastStreamID, e.ErrCode, e.DebugData)
+}
+
+func http2isEOFOrNetReadError(err error) bool {
+	if err == io.EOF {
+		return true
+	}
+	ne, ok := err.(*net.OpError)
+	return ok && ne.Op == "read"
+}
+
+func (rl *http2clientConnReadLoop) cleanup() {
+	cc := rl.cc
+	cc.t.connPool().MarkDead(cc)
+	defer cc.closeConn()
+	defer close(cc.readerDone)
+
+	if cc.idleTimer != nil {
+		cc.idleTimer.Stop()
+	}
+
+	// Close any response bodies if the server closes prematurely.
+	// TODO: also do this if we've written the headers but not
+	// gotten a response yet.
+	err := cc.readerErr
+	cc.mu.Lock()
+	if cc.goAway != nil && http2isEOFOrNetReadError(err) {
+		err = http2GoAwayError{
+			LastStreamID: cc.goAway.LastStreamID,
+			ErrCode:      cc.goAway.ErrCode,
+			DebugData:    cc.goAwayDebug,
+		}
+	} else if err == io.EOF {
+		err = io.ErrUnexpectedEOF
+	}
+	cc.closed = true
+	for _, cs := range cc.streams {
+		select {
+		case <-cs.peerClosed:
+			// The server closed the stream before closing the conn,
+			// so no need to interrupt it.
+		default:
+			cs.abortStreamLocked(err)
+		}
+	}
+	cc.cond.Broadcast()
+	cc.mu.Unlock()
+}
+
+// countReadFrameError calls Transport.CountError with a string
+// representing err.
+func (cc *http2ClientConn) countReadFrameError(err error) {
+	f := cc.t.CountError
+	if f == nil || err == nil {
+		return
+	}
+	if ce, ok := err.(http2ConnectionError); ok {
+		errCode := http2ErrCode(ce)
+		f(fmt.Sprintf("read_frame_conn_error_%s", errCode.stringToken()))
+		return
+	}
+	if errors.Is(err, io.EOF) {
+		f("read_frame_eof")
+		return
+	}
+	if errors.Is(err, io.ErrUnexpectedEOF) {
+		f("read_frame_unexpected_eof")
+		return
+	}
+	if errors.Is(err, http2ErrFrameTooLarge) {
+		f("read_frame_too_large")
+		return
+	}
+	f("read_frame_other")
+}
+
+func (rl *http2clientConnReadLoop) run() error {
+	cc := rl.cc
+	gotSettings := false
+	readIdleTimeout := cc.t.ReadIdleTimeout
+	var t *time.Timer
+	if readIdleTimeout != 0 {
+		t = time.AfterFunc(readIdleTimeout, cc.healthCheck)
+		defer t.Stop()
+	}
+	for {
+		f, err := cc.fr.ReadFrame()
+		if t != nil {
+			t.Reset(readIdleTimeout)
+		}
+		if err != nil {
+			cc.vlogf("http2: Transport readFrame error on conn %p: (%T) %v", cc, err, err)
+		}
+		if se, ok := err.(http2StreamError); ok {
+			if cs := rl.streamByID(se.StreamID); cs != nil {
+				if se.Cause == nil {
+					se.Cause = cc.fr.errDetail
+				}
+				rl.endStreamError(cs, se)
+			}
+			continue
+		} else if err != nil {
+			cc.countReadFrameError(err)
+			return err
+		}
+		if http2VerboseLogs {
+			cc.vlogf("http2: Transport received %s", http2summarizeFrame(f))
+		}
+		if !gotSettings {
+			if _, ok := f.(*http2SettingsFrame); !ok {
+				cc.logf("protocol error: received %T before a SETTINGS frame", f)
+				return http2ConnectionError(http2ErrCodeProtocol)
+			}
+			gotSettings = true
+		}
+
+		switch f := f.(type) {
+		case *http2MetaHeadersFrame:
+			err = rl.processHeaders(f)
+		case *http2DataFrame:
+			err = rl.processData(f)
+		case *http2GoAwayFrame:
+			err = rl.processGoAway(f)
+		case *http2RSTStreamFrame:
+			err = rl.processResetStream(f)
+		case *http2SettingsFrame:
+			err = rl.processSettings(f)
+		case *http2PushPromiseFrame:
+			err = rl.processPushPromise(f)
+		case *http2WindowUpdateFrame:
+			err = rl.processWindowUpdate(f)
+		case *http2PingFrame:
+			err = rl.processPing(f)
+		default:
+			cc.logf("Transport: unhandled response frame type %T", f)
+		}
+		if err != nil {
+			if http2VerboseLogs {
+				cc.vlogf("http2: Transport conn %p received error from processing frame %v: %v", cc, http2summarizeFrame(f), err)
+			}
+			return err
+		}
+	}
+}
+
+func (rl *http2clientConnReadLoop) processHeaders(f *http2MetaHeadersFrame) error {
+	cs := rl.streamByID(f.StreamID)
+	if cs == nil {
+		// We'd get here if we canceled a request while the
+		// server had its response still in flight. So if this
+		// was just something we canceled, ignore it.
+		return nil
+	}
+	if cs.readClosed {
+		rl.endStreamError(cs, http2StreamError{
+			StreamID: f.StreamID,
+			Code:     http2ErrCodeProtocol,
+			Cause:    errors.New("protocol error: headers after END_STREAM"),
+		})
+		return nil
+	}
+	if !cs.firstByte {
+		if cs.trace != nil {
+			// TODO(bradfitz): move first response byte earlier,
+			// when we first read the 9 byte header, not waiting
+			// until all the HEADERS+CONTINUATION frames have been
+			// merged. This works for now.
+			http2traceFirstResponseByte(cs.trace)
+		}
+		cs.firstByte = true
+	}
+	if !cs.pastHeaders {
+		cs.pastHeaders = true
+	} else {
+		return rl.processTrailers(cs, f)
+	}
+
+	res, err := rl.handleResponse(cs, f)
+	if err != nil {
+		if _, ok := err.(http2ConnectionError); ok {
+			return err
+		}
+		// Any other error type is a stream error.
+		rl.endStreamError(cs, http2StreamError{
+			StreamID: f.StreamID,
+			Code:     http2ErrCodeProtocol,
+			Cause:    err,
+		})
+		return nil // return nil from process* funcs to keep conn alive
+	}
+	if res == nil {
+		// (nil, nil) special case. See handleResponse docs.
+		return nil
+	}
+	cs.resTrailer = &res.Trailer
+	cs.res = res
+	close(cs.respHeaderRecv)
+	if f.StreamEnded() {
+		rl.endStream(cs)
+	}
+	return nil
+}
+
+// may return error types nil, or ConnectionError. Any other error value
+// is a StreamError of type ErrCodeProtocol. The returned error in that case
+// is the detail.
+//
+// As a special case, handleResponse may return (nil, nil) to skip the
+// frame (currently only used for 1xx responses).
+func (rl *http2clientConnReadLoop) handleResponse(cs *http2clientStream, f *http2MetaHeadersFrame) (*Response, error) {
+	if f.Truncated {
+		return nil, http2errResponseHeaderListSize
+	}
+
+	status := f.PseudoValue("status")
+	if status == "" {
+		return nil, errors.New("malformed response from server: missing status pseudo header")
+	}
+	statusCode, err := strconv.Atoi(status)
+	if err != nil {
+		return nil, errors.New("malformed response from server: malformed non-numeric status pseudo header")
+	}
+
+	regularFields := f.RegularFields()
+	strs := make([]string, len(regularFields))
+	header := make(Header, len(regularFields))
+	res := &Response{
+		Proto:      "HTTP/2.0",
+		ProtoMajor: 2,
+		Header:     header,
+		StatusCode: statusCode,
+		Status:     status + " " + StatusText(statusCode),
+	}
+	for _, hf := range regularFields {
+		key := CanonicalHeaderKey(hf.Name)
+		if key == "Trailer" {
+			t := res.Trailer
+			if t == nil {
+				t = make(Header)
+				res.Trailer = t
+			}
+			http2foreachHeaderElement(hf.Value, func(v string) {
+				t[CanonicalHeaderKey(v)] = nil
+			})
+		} else {
+			vv := header[key]
+			if vv == nil && len(strs) > 0 {
+				// More than likely this will be a single-element key.
+				// Most headers aren't multi-valued.
+				// Set the capacity on strs[0] to 1, so any future append
+				// won't extend the slice into the other strings.
+				vv, strs = strs[:1:1], strs[1:]
+				vv[0] = hf.Value
+				header[key] = vv
+			} else {
+				header[key] = append(vv, hf.Value)
+			}
+		}
+	}
+
+	if statusCode >= 100 && statusCode <= 199 {
+		if f.StreamEnded() {
+			return nil, errors.New("1xx informational response with END_STREAM flag")
+		}
+		cs.num1xx++
+		const max1xxResponses = 5 // arbitrary bound on number of informational responses, same as net/http
+		if cs.num1xx > max1xxResponses {
+			return nil, errors.New("http2: too many 1xx informational responses")
+		}
+		if fn := cs.get1xxTraceFunc(); fn != nil {
+			if err := fn(statusCode, textproto.MIMEHeader(header)); err != nil {
+				return nil, err
+			}
+		}
+		if statusCode == 100 {
+			http2traceGot100Continue(cs.trace)
+			select {
+			case cs.on100 <- struct{}{}:
+			default:
+			}
+		}
+		cs.pastHeaders = false // do it all again
+		return nil, nil
+	}
+
+	res.ContentLength = -1
+	if clens := res.Header["Content-Length"]; len(clens) == 1 {
+		if cl, err := strconv.ParseUint(clens[0], 10, 63); err == nil {
+			res.ContentLength = int64(cl)
+		} else {
+			// TODO: care? unlike http/1, it won't mess up our framing, so it's
+			// more safe smuggling-wise to ignore.
+		}
+	} else if len(clens) > 1 {
+		// TODO: care? unlike http/1, it won't mess up our framing, so it's
+		// more safe smuggling-wise to ignore.
+	} else if f.StreamEnded() && !cs.isHead {
+		res.ContentLength = 0
+	}
+
+	if cs.isHead {
+		res.Body = http2noBody
+		return res, nil
+	}
+
+	if f.StreamEnded() {
+		if res.ContentLength > 0 {
+			res.Body = http2missingBody{}
+		} else {
+			res.Body = http2noBody
+		}
+		return res, nil
+	}
+
+	cs.bufPipe.setBuffer(&http2dataBuffer{expected: res.ContentLength})
+	cs.bytesRemain = res.ContentLength
+	res.Body = http2transportResponseBody{cs}
+
+	if cs.requestedGzip && http2asciiEqualFold(res.Header.Get("Content-Encoding"), "gzip") {
+		res.Header.Del("Content-Encoding")
+		res.Header.Del("Content-Length")
+		res.ContentLength = -1
+		res.Body = &http2gzipReader{body: res.Body}
+		res.Uncompressed = true
+	}
+	return res, nil
+}
+
+func (rl *http2clientConnReadLoop) processTrailers(cs *http2clientStream, f *http2MetaHeadersFrame) error {
+	if cs.pastTrailers {
+		// Too many HEADERS frames for this stream.
+		return http2ConnectionError(http2ErrCodeProtocol)
+	}
+	cs.pastTrailers = true
+	if !f.StreamEnded() {
+		// We expect that any headers for trailers also
+		// has END_STREAM.
+		return http2ConnectionError(http2ErrCodeProtocol)
+	}
+	if len(f.PseudoFields()) > 0 {
+		// No pseudo header fields are defined for trailers.
+		// TODO: ConnectionError might be overly harsh? Check.
+		return http2ConnectionError(http2ErrCodeProtocol)
+	}
+
+	trailer := make(Header)
+	for _, hf := range f.RegularFields() {
+		key := CanonicalHeaderKey(hf.Name)
+		trailer[key] = append(trailer[key], hf.Value)
+	}
+	cs.trailer = trailer
+
+	rl.endStream(cs)
+	return nil
+}
+
+// transportResponseBody is the concrete type of Transport.RoundTrip's
+// Response.Body. It is an io.ReadCloser.
+type http2transportResponseBody struct {
+	cs *http2clientStream
+}
+
+func (b http2transportResponseBody) Read(p []byte) (n int, err error) {
+	cs := b.cs
+	cc := cs.cc
+
+	if cs.readErr != nil {
+		return 0, cs.readErr
+	}
+	n, err = b.cs.bufPipe.Read(p)
+	if cs.bytesRemain != -1 {
+		if int64(n) > cs.bytesRemain {
+			n = int(cs.bytesRemain)
+			if err == nil {
+				err = errors.New("net/http: server replied with more than declared Content-Length; truncated")
+				cs.abortStream(err)
+			}
+			cs.readErr = err
+			return int(cs.bytesRemain), err
+		}
+		cs.bytesRemain -= int64(n)
+		if err == io.EOF && cs.bytesRemain > 0 {
+			err = io.ErrUnexpectedEOF
+			cs.readErr = err
+			return n, err
+		}
+	}
+	if n == 0 {
+		// No flow control tokens to send back.
+		return
+	}
+
+	cc.mu.Lock()
+	var connAdd, streamAdd int32
+	// Check the conn-level first, before the stream-level.
+	if v := cc.inflow.available(); v < http2transportDefaultConnFlow/2 {
+		connAdd = http2transportDefaultConnFlow - v
+		cc.inflow.add(connAdd)
+	}
+	if err == nil { // No need to refresh if the stream is over or failed.
+		// Consider any buffered body data (read from the conn but not
+		// consumed by the client) when computing flow control for this
+		// stream.
+		v := int(cs.inflow.available()) + cs.bufPipe.Len()
+		if v < http2transportDefaultStreamFlow-http2transportDefaultStreamMinRefresh {
+			streamAdd = int32(http2transportDefaultStreamFlow - v)
+			cs.inflow.add(streamAdd)
+		}
+	}
+	cc.mu.Unlock()
+
+	if connAdd != 0 || streamAdd != 0 {
+		cc.wmu.Lock()
+		defer cc.wmu.Unlock()
+		if connAdd != 0 {
+			cc.fr.WriteWindowUpdate(0, http2mustUint31(connAdd))
+		}
+		if streamAdd != 0 {
+			cc.fr.WriteWindowUpdate(cs.ID, http2mustUint31(streamAdd))
+		}
+		cc.bw.Flush()
+	}
+	return
+}
+
+var http2errClosedResponseBody = errors.New("http2: response body closed")
+
+func (b http2transportResponseBody) Close() error {
+	cs := b.cs
+	cc := cs.cc
+
+	unread := cs.bufPipe.Len()
+	if unread > 0 {
+		cc.mu.Lock()
+		// Return connection-level flow control.
+		if unread > 0 {
+			cc.inflow.add(int32(unread))
+		}
+		cc.mu.Unlock()
+
+		// TODO(dneil): Acquiring this mutex can block indefinitely.
+		// Move flow control return to a goroutine?
+		cc.wmu.Lock()
+		// Return connection-level flow control.
+		if unread > 0 {
+			cc.fr.WriteWindowUpdate(0, uint32(unread))
+		}
+		cc.bw.Flush()
+		cc.wmu.Unlock()
+	}
+
+	cs.bufPipe.BreakWithError(http2errClosedResponseBody)
+	cs.abortStream(http2errClosedResponseBody)
+
+	select {
+	case <-cs.donec:
+	case <-cs.ctx.Done():
+		// See golang/go#49366: The net/http package can cancel the
+		// request context after the response body is fully read.
+		// Don't treat this as an error.
+		return nil
+	case <-cs.reqCancel:
+		return http2errRequestCanceled
+	}
+	return nil
+}
+
+func (rl *http2clientConnReadLoop) processData(f *http2DataFrame) error {
+	cc := rl.cc
+	cs := rl.streamByID(f.StreamID)
+	data := f.Data()
+	if cs == nil {
+		cc.mu.Lock()
+		neverSent := cc.nextStreamID
+		cc.mu.Unlock()
+		if f.StreamID >= neverSent {
+			// We never asked for this.
+			cc.logf("http2: Transport received unsolicited DATA frame; closing connection")
+			return http2ConnectionError(http2ErrCodeProtocol)
+		}
+		// We probably did ask for this, but canceled. Just ignore it.
+		// TODO: be stricter here? only silently ignore things which
+		// we canceled, but not things which were closed normally
+		// by the peer? Tough without accumulating too much state.
+
+		// But at least return their flow control:
+		if f.Length > 0 {
+			cc.mu.Lock()
+			cc.inflow.add(int32(f.Length))
+			cc.mu.Unlock()
+
+			cc.wmu.Lock()
+			cc.fr.WriteWindowUpdate(0, uint32(f.Length))
+			cc.bw.Flush()
+			cc.wmu.Unlock()
+		}
+		return nil
+	}
+	if cs.readClosed {
+		cc.logf("protocol error: received DATA after END_STREAM")
+		rl.endStreamError(cs, http2StreamError{
+			StreamID: f.StreamID,
+			Code:     http2ErrCodeProtocol,
+		})
+		return nil
+	}
+	if !cs.firstByte {
+		cc.logf("protocol error: received DATA before a HEADERS frame")
+		rl.endStreamError(cs, http2StreamError{
+			StreamID: f.StreamID,
+			Code:     http2ErrCodeProtocol,
+		})
+		return nil
+	}
+	if f.Length > 0 {
+		if cs.isHead && len(data) > 0 {
+			cc.logf("protocol error: received DATA on a HEAD request")
+			rl.endStreamError(cs, http2StreamError{
+				StreamID: f.StreamID,
+				Code:     http2ErrCodeProtocol,
+			})
+			return nil
+		}
+		// Check connection-level flow control.
+		cc.mu.Lock()
+		if cs.inflow.available() >= int32(f.Length) {
+			cs.inflow.take(int32(f.Length))
+		} else {
+			cc.mu.Unlock()
+			return http2ConnectionError(http2ErrCodeFlowControl)
+		}
+		// Return any padded flow control now, since we won't
+		// refund it later on body reads.
+		var refund int
+		if pad := int(f.Length) - len(data); pad > 0 {
+			refund += pad
+		}
+
+		didReset := false
+		var err error
+		if len(data) > 0 {
+			if _, err = cs.bufPipe.Write(data); err != nil {
+				// Return len(data) now if the stream is already closed,
+				// since data will never be read.
+				didReset = true
+				refund += len(data)
+			}
+		}
+
+		if refund > 0 {
+			cc.inflow.add(int32(refund))
+			if !didReset {
+				cs.inflow.add(int32(refund))
+			}
+		}
+		cc.mu.Unlock()
+
+		if refund > 0 {
+			cc.wmu.Lock()
+			cc.fr.WriteWindowUpdate(0, uint32(refund))
+			if !didReset {
+				cc.fr.WriteWindowUpdate(cs.ID, uint32(refund))
+			}
+			cc.bw.Flush()
+			cc.wmu.Unlock()
+		}
+
+		if err != nil {
+			rl.endStreamError(cs, err)
+			return nil
+		}
+	}
+
+	if f.StreamEnded() {
+		rl.endStream(cs)
+	}
+	return nil
+}
+
+func (rl *http2clientConnReadLoop) endStream(cs *http2clientStream) {
+	// TODO: check that any declared content-length matches, like
+	// server.go's (*stream).endStream method.
+	if !cs.readClosed {
+		cs.readClosed = true
+		// Close cs.bufPipe and cs.peerClosed with cc.mu held to avoid a
+		// race condition: The caller can read io.EOF from Response.Body
+		// and close the body before we close cs.peerClosed, causing
+		// cleanupWriteRequest to send a RST_STREAM.
+		rl.cc.mu.Lock()
+		defer rl.cc.mu.Unlock()
+		cs.bufPipe.closeWithErrorAndCode(io.EOF, cs.copyTrailers)
+		close(cs.peerClosed)
+	}
+}
+
+func (rl *http2clientConnReadLoop) endStreamError(cs *http2clientStream, err error) {
+	cs.readAborted = true
+	cs.abortStream(err)
+}
+
+func (rl *http2clientConnReadLoop) streamByID(id uint32) *http2clientStream {
+	rl.cc.mu.Lock()
+	defer rl.cc.mu.Unlock()
+	cs := rl.cc.streams[id]
+	if cs != nil && !cs.readAborted {
+		return cs
+	}
+	return nil
+}
+
+func (cs *http2clientStream) copyTrailers() {
+	for k, vv := range cs.trailer {
+		t := cs.resTrailer
+		if *t == nil {
+			*t = make(Header)
+		}
+		(*t)[k] = vv
+	}
+}
+
+func (rl *http2clientConnReadLoop) processGoAway(f *http2GoAwayFrame) error {
+	cc := rl.cc
+	cc.t.connPool().MarkDead(cc)
+	if f.ErrCode != 0 {
+		// TODO: deal with GOAWAY more. particularly the error code
+		cc.vlogf("transport got GOAWAY with error code = %v", f.ErrCode)
+		if fn := cc.t.CountError; fn != nil {
+			fn("recv_goaway_" + f.ErrCode.stringToken())
+		}
+
+	}
+	cc.setGoAway(f)
+	return nil
+}
+
+func (rl *http2clientConnReadLoop) processSettings(f *http2SettingsFrame) error {
+	cc := rl.cc
+	// Locking both mu and wmu here allows frame encoding to read settings with only wmu held.
+	// Acquiring wmu when f.IsAck() is unnecessary, but convenient and mostly harmless.
+	cc.wmu.Lock()
+	defer cc.wmu.Unlock()
+
+	if err := rl.processSettingsNoWrite(f); err != nil {
+		return err
+	}
+	if !f.IsAck() {
+		cc.fr.WriteSettingsAck()
+		cc.bw.Flush()
+	}
+	return nil
+}
+
+func (rl *http2clientConnReadLoop) processSettingsNoWrite(f *http2SettingsFrame) error {
+	cc := rl.cc
+	cc.mu.Lock()
+	defer cc.mu.Unlock()
+
+	if f.IsAck() {
+		if cc.wantSettingsAck {
+			cc.wantSettingsAck = false
+			return nil
+		}
+		return http2ConnectionError(http2ErrCodeProtocol)
+	}
+
+	var seenMaxConcurrentStreams bool
+	err := f.ForeachSetting(func(s http2Setting) error {
+		switch s.ID {
+		case http2SettingMaxFrameSize:
+			cc.maxFrameSize = s.Val
+		case http2SettingMaxConcurrentStreams:
+			cc.maxConcurrentStreams = s.Val
+			seenMaxConcurrentStreams = true
+		case http2SettingMaxHeaderListSize:
+			cc.peerMaxHeaderListSize = uint64(s.Val)
+		case http2SettingInitialWindowSize:
+			// Values above the maximum flow-control
+			// window size of 2^31-1 MUST be treated as a
+			// connection error (Section 5.4.1) of type
+			// FLOW_CONTROL_ERROR.
+			if s.Val > math.MaxInt32 {
+				return http2ConnectionError(http2ErrCodeFlowControl)
+			}
+
+			// Adjust flow control of currently-open
+			// frames by the difference of the old initial
+			// window size and this one.
+			delta := int32(s.Val) - int32(cc.initialWindowSize)
+			for _, cs := range cc.streams {
+				cs.flow.add(delta)
+			}
+			cc.cond.Broadcast()
+
+			cc.initialWindowSize = s.Val
+		default:
+			// TODO(bradfitz): handle more settings? SETTINGS_HEADER_TABLE_SIZE probably.
+			cc.vlogf("Unhandled Setting: %v", s)
+		}
+		return nil
+	})
+	if err != nil {
+		return err
+	}
+
+	if !cc.seenSettings {
+		if !seenMaxConcurrentStreams {
+			// This was the servers initial SETTINGS frame and it
+			// didn't contain a MAX_CONCURRENT_STREAMS field so
+			// increase the number of concurrent streams this
+			// connection can establish to our default.
+			cc.maxConcurrentStreams = http2defaultMaxConcurrentStreams
+		}
+		cc.seenSettings = true
+	}
+
+	return nil
+}
+
+func (rl *http2clientConnReadLoop) processWindowUpdate(f *http2WindowUpdateFrame) error {
+	cc := rl.cc
+	cs := rl.streamByID(f.StreamID)
+	if f.StreamID != 0 && cs == nil {
+		return nil
+	}
+
+	cc.mu.Lock()
+	defer cc.mu.Unlock()
+
+	fl := &cc.flow
+	if cs != nil {
+		fl = &cs.flow
+	}
+	if !fl.add(int32(f.Increment)) {
+		return http2ConnectionError(http2ErrCodeFlowControl)
+	}
+	cc.cond.Broadcast()
+	return nil
+}
+
+func (rl *http2clientConnReadLoop) processResetStream(f *http2RSTStreamFrame) error {
+	cs := rl.streamByID(f.StreamID)
+	if cs == nil {
+		// TODO: return error if server tries to RST_STREAM an idle stream
+		return nil
+	}
+	serr := http2streamError(cs.ID, f.ErrCode)
+	serr.Cause = http2errFromPeer
+	if f.ErrCode == http2ErrCodeProtocol {
+		rl.cc.SetDoNotReuse()
+	}
+	if fn := cs.cc.t.CountError; fn != nil {
+		fn("recv_rststream_" + f.ErrCode.stringToken())
+	}
+	cs.abortStream(serr)
+
+	cs.bufPipe.CloseWithError(serr)
+	return nil
+}
+
+// Ping sends a PING frame to the server and waits for the ack.
+func (cc *http2ClientConn) Ping(ctx context.Context) error {
+	c := make(chan struct{})
+	// Generate a random payload
+	var p [8]byte
+	for {
+		if _, err := rand.Read(p[:]); err != nil {
+			return err
+		}
+		cc.mu.Lock()
+		// check for dup before insert
+		if _, found := cc.pings[p]; !found {
+			cc.pings[p] = c
+			cc.mu.Unlock()
+			break
+		}
+		cc.mu.Unlock()
+	}
+	errc := make(chan error, 1)
+	go func() {
+		cc.wmu.Lock()
+		defer cc.wmu.Unlock()
+		if err := cc.fr.WritePing(false, p); err != nil {
+			errc <- err
+			return
+		}
+		if err := cc.bw.Flush(); err != nil {
+			errc <- err
+			return
+		}
+	}()
+	select {
+	case <-c:
+		return nil
+	case err := <-errc:
+		return err
+	case <-ctx.Done():
+		return ctx.Err()
+	case <-cc.readerDone:
+		// connection closed
+		return cc.readerErr
+	}
+}
+
+func (rl *http2clientConnReadLoop) processPing(f *http2PingFrame) error {
+	if f.IsAck() {
+		cc := rl.cc
+		cc.mu.Lock()
+		defer cc.mu.Unlock()
+		// If ack, notify listener if any
+		if c, ok := cc.pings[f.Data]; ok {
+			close(c)
+			delete(cc.pings, f.Data)
+		}
+		return nil
+	}
+	cc := rl.cc
+	cc.wmu.Lock()
+	defer cc.wmu.Unlock()
+	if err := cc.fr.WritePing(true, f.Data); err != nil {
+		return err
+	}
+	return cc.bw.Flush()
+}
+
+func (rl *http2clientConnReadLoop) processPushPromise(f *http2PushPromiseFrame) error {
+	// We told the peer we don't want them.
+	// Spec says:
+	// "PUSH_PROMISE MUST NOT be sent if the SETTINGS_ENABLE_PUSH
+	// setting of the peer endpoint is set to 0. An endpoint that
+	// has set this setting and has received acknowledgement MUST
+	// treat the receipt of a PUSH_PROMISE frame as a connection
+	// error (Section 5.4.1) of type PROTOCOL_ERROR."
+	return http2ConnectionError(http2ErrCodeProtocol)
+}
+
+func (cc *http2ClientConn) writeStreamReset(streamID uint32, code http2ErrCode, err error) {
+	// TODO: map err to more interesting error codes, once the
+	// HTTP community comes up with some. But currently for
+	// RST_STREAM there's no equivalent to GOAWAY frame's debug
+	// data, and the error codes are all pretty vague ("cancel").
+	cc.wmu.Lock()
+	cc.fr.WriteRSTStream(streamID, code)
+	cc.bw.Flush()
+	cc.wmu.Unlock()
+}
+
+var (
+	http2errResponseHeaderListSize = errors.New("http2: response header list larger than advertised limit")
+	http2errRequestHeaderListSize  = errors.New("http2: request header list larger than peer's advertised limit")
+)
+
+func (cc *http2ClientConn) logf(format string, args ...interface{}) {
+	cc.t.logf(format, args...)
+}
+
+func (cc *http2ClientConn) vlogf(format string, args ...interface{}) {
+	cc.t.vlogf(format, args...)
+}
+
+func (t *http2Transport) vlogf(format string, args ...interface{}) {
+	if http2VerboseLogs {
+		t.logf(format, args...)
+	}
+}
+
+func (t *http2Transport) logf(format string, args ...interface{}) {
+	log.Printf(format, args...)
+}
+
+var http2noBody io.ReadCloser = http2noBodyReader{}
+
+type http2noBodyReader struct{}
+
+func (http2noBodyReader) Close() error { return nil }
+
+func (http2noBodyReader) Read([]byte) (int, error) { return 0, io.EOF }
+
+type http2missingBody struct{}
+
+func (http2missingBody) Close() error { return nil }
+
+func (http2missingBody) Read([]byte) (int, error) { return 0, io.ErrUnexpectedEOF }
+
+func http2strSliceContains(ss []string, s string) bool {
+	for _, v := range ss {
+		if v == s {
+			return true
+		}
+	}
+	return false
+}
+
+type http2erringRoundTripper struct{ err error }
+
+func (rt http2erringRoundTripper) RoundTripErr() error { return rt.err }
+
+func (rt http2erringRoundTripper) RoundTrip(*Request) (*Response, error) { return nil, rt.err }
+
+// gzipReader wraps a response body so it can lazily
+// call gzip.NewReader on the first call to Read
+type http2gzipReader struct {
+	_    http2incomparable
+	body io.ReadCloser // underlying Response.Body
+	zr   *gzip.Reader  // lazily-initialized gzip reader
+	zerr error         // sticky error
+}
+
+func (gz *http2gzipReader) Read(p []byte) (n int, err error) {
+	if gz.zerr != nil {
+		return 0, gz.zerr
+	}
+	if gz.zr == nil {
+		gz.zr, err = gzip.NewReader(gz.body)
+		if err != nil {
+			gz.zerr = err
+			return 0, err
+		}
+	}
+	return gz.zr.Read(p)
+}
+
+func (gz *http2gzipReader) Close() error {
+	return gz.body.Close()
+}
+
+type http2errorReader struct{ err error }
+
+func (r http2errorReader) Read(p []byte) (int, error) { return 0, r.err }
+
+// isConnectionCloseRequest reports whether req should use its own
+// connection for a single request and then close the connection.
+func http2isConnectionCloseRequest(req *Request) bool {
+	return req.Close || httpguts.HeaderValuesContainsToken(req.Header["Connection"], "close")
+}
+
+// registerHTTPSProtocol calls Transport.RegisterProtocol but
+// converting panics into errors.
+func http2registerHTTPSProtocol(t *Transport, rt http2noDialH2RoundTripper) (err error) {
+	defer func() {
+		if e := recover(); e != nil {
+			err = fmt.Errorf("%v", e)
+		}
+	}()
+	t.RegisterProtocol("https", rt)
+	return nil
+}
+
+// noDialH2RoundTripper is a RoundTripper which only tries to complete the request
+// if there's already has a cached connection to the host.
+// (The field is exported so it can be accessed via reflect from net/http; tested
+// by TestNoDialH2RoundTripperType)
+type http2noDialH2RoundTripper struct{ *http2Transport }
+
+func (rt http2noDialH2RoundTripper) RoundTrip(req *Request) (*Response, error) {
+	res, err := rt.http2Transport.RoundTrip(req)
+	if http2isNoCachedConnError(err) {
+		return nil, ErrSkipAltProtocol
+	}
+	return res, err
+}
+
+func (t *http2Transport) idleConnTimeout() time.Duration {
+	if t.t1 != nil {
+		return t.t1.IdleConnTimeout
+	}
+	return 0
+}
+
+func http2traceGetConn(req *Request, hostPort string) {
+	trace := httptrace.ContextClientTrace(req.Context())
+	if trace == nil || trace.GetConn == nil {
+		return
+	}
+	trace.GetConn(hostPort)
+}
+
+func http2traceGotConn(req *Request, cc *http2ClientConn, reused bool) {
+	trace := httptrace.ContextClientTrace(req.Context())
+	if trace == nil || trace.GotConn == nil {
+		return
+	}
+	ci := httptrace.GotConnInfo{Conn: cc.tconn}
+	ci.Reused = reused
+	cc.mu.Lock()
+	ci.WasIdle = len(cc.streams) == 0 && reused
+	if ci.WasIdle && !cc.lastActive.IsZero() {
+		ci.IdleTime = time.Now().Sub(cc.lastActive)
+	}
+	cc.mu.Unlock()
+
+	trace.GotConn(ci)
+}
+
+func http2traceWroteHeaders(trace *httptrace.ClientTrace) {
+	if trace != nil && trace.WroteHeaders != nil {
+		trace.WroteHeaders()
+	}
+}
+
+func http2traceGot100Continue(trace *httptrace.ClientTrace) {
+	if trace != nil && trace.Got100Continue != nil {
+		trace.Got100Continue()
+	}
+}
+
+func http2traceWait100Continue(trace *httptrace.ClientTrace) {
+	if trace != nil && trace.Wait100Continue != nil {
+		trace.Wait100Continue()
+	}
+}
+
+func http2traceWroteRequest(trace *httptrace.ClientTrace, err error) {
+	if trace != nil && trace.WroteRequest != nil {
+		trace.WroteRequest(httptrace.WroteRequestInfo{Err: err})
+	}
+}
+
+func http2traceFirstResponseByte(trace *httptrace.ClientTrace) {
+	if trace != nil && trace.GotFirstResponseByte != nil {
+		trace.GotFirstResponseByte()
+	}
+}
+
+// writeFramer is implemented by any type that is used to write frames.
+type http2writeFramer interface {
+	writeFrame(http2writeContext) error
+
+	// staysWithinBuffer reports whether this writer promises that
+	// it will only write less than or equal to size bytes, and it
+	// won't Flush the write context.
+	staysWithinBuffer(size int) bool
+}
+
+// writeContext is the interface needed by the various frame writer
+// types below. All the writeFrame methods below are scheduled via the
+// frame writing scheduler (see writeScheduler in writesched.go).
+//
+// This interface is implemented by *serverConn.
+//
+// TODO: decide whether to a) use this in the client code (which didn't
+// end up using this yet, because it has a simpler design, not
+// currently implementing priorities), or b) delete this and
+// make the server code a bit more concrete.
+type http2writeContext interface {
+	Framer() *http2Framer
+	Flush() error
+	CloseConn() error
+	// HeaderEncoder returns an HPACK encoder that writes to the
+	// returned buffer.
+	HeaderEncoder() (*hpack.Encoder, *bytes.Buffer)
+}
+
+// writeEndsStream reports whether w writes a frame that will transition
+// the stream to a half-closed local state. This returns false for RST_STREAM,
+// which closes the entire stream (not just the local half).
+func http2writeEndsStream(w http2writeFramer) bool {
+	switch v := w.(type) {
+	case *http2writeData:
+		return v.endStream
+	case *http2writeResHeaders:
+		return v.endStream
+	case nil:
+		// This can only happen if the caller reuses w after it's
+		// been intentionally nil'ed out to prevent use. Keep this
+		// here to catch future refactoring breaking it.
+		panic("writeEndsStream called on nil writeFramer")
+	}
+	return false
+}
+
+type http2flushFrameWriter struct{}
+
+func (http2flushFrameWriter) writeFrame(ctx http2writeContext) error {
+	return ctx.Flush()
+}
+
+func (http2flushFrameWriter) staysWithinBuffer(max int) bool { return false }
+
+type http2writeSettings []http2Setting
+
+func (s http2writeSettings) staysWithinBuffer(max int) bool {
+	const settingSize = 6 // uint16 + uint32
+	return http2frameHeaderLen+settingSize*len(s) <= max
+
+}
+
+func (s http2writeSettings) writeFrame(ctx http2writeContext) error {
+	return ctx.Framer().WriteSettings([]http2Setting(s)...)
+}
+
+type http2writeGoAway struct {
+	maxStreamID uint32
+	code        http2ErrCode
+}
+
+func (p *http2writeGoAway) writeFrame(ctx http2writeContext) error {
+	err := ctx.Framer().WriteGoAway(p.maxStreamID, p.code, nil)
+	ctx.Flush() // ignore error: we're hanging up on them anyway
+	return err
+}
+
+func (*http2writeGoAway) staysWithinBuffer(max int) bool { return false } // flushes
+
+type http2writeData struct {
+	streamID  uint32
+	p         []byte
+	endStream bool
+}
+
+func (w *http2writeData) String() string {
+	return fmt.Sprintf("writeData(stream=%d, p=%d, endStream=%v)", w.streamID, len(w.p), w.endStream)
+}
+
+func (w *http2writeData) writeFrame(ctx http2writeContext) error {
+	return ctx.Framer().WriteData(w.streamID, w.endStream, w.p)
+}
+
+func (w *http2writeData) staysWithinBuffer(max int) bool {
+	return http2frameHeaderLen+len(w.p) <= max
+}
+
+// handlerPanicRST is the message sent from handler goroutines when
+// the handler panics.
+type http2handlerPanicRST struct {
+	StreamID uint32
+}
+
+func (hp http2handlerPanicRST) writeFrame(ctx http2writeContext) error {
+	return ctx.Framer().WriteRSTStream(hp.StreamID, http2ErrCodeInternal)
+}
+
+func (hp http2handlerPanicRST) staysWithinBuffer(max int) bool { return http2frameHeaderLen+4 <= max }
+
+func (se http2StreamError) writeFrame(ctx http2writeContext) error {
+	return ctx.Framer().WriteRSTStream(se.StreamID, se.Code)
+}
+
+func (se http2StreamError) staysWithinBuffer(max int) bool { return http2frameHeaderLen+4 <= max }
+
+type http2writePingAck struct{ pf *http2PingFrame }
+
+func (w http2writePingAck) writeFrame(ctx http2writeContext) error {
+	return ctx.Framer().WritePing(true, w.pf.Data)
+}
+
+func (w http2writePingAck) staysWithinBuffer(max int) bool {
+	return http2frameHeaderLen+len(w.pf.Data) <= max
+}
+
+type http2writeSettingsAck struct{}
+
+func (http2writeSettingsAck) writeFrame(ctx http2writeContext) error {
+	return ctx.Framer().WriteSettingsAck()
+}
+
+func (http2writeSettingsAck) staysWithinBuffer(max int) bool { return http2frameHeaderLen <= max }
+
+// splitHeaderBlock splits headerBlock into fragments so that each fragment fits
+// in a single frame, then calls fn for each fragment. firstFrag/lastFrag are true
+// for the first/last fragment, respectively.
+func http2splitHeaderBlock(ctx http2writeContext, headerBlock []byte, fn func(ctx http2writeContext, frag []byte, firstFrag, lastFrag bool) error) error {
+	// For now we're lazy and just pick the minimum MAX_FRAME_SIZE
+	// that all peers must support (16KB). Later we could care
+	// more and send larger frames if the peer advertised it, but
+	// there's little point. Most headers are small anyway (so we
+	// generally won't have CONTINUATION frames), and extra frames
+	// only waste 9 bytes anyway.
+	const maxFrameSize = 16384
+
+	first := true
+	for len(headerBlock) > 0 {
+		frag := headerBlock
+		if len(frag) > maxFrameSize {
+			frag = frag[:maxFrameSize]
+		}
+		headerBlock = headerBlock[len(frag):]
+		if err := fn(ctx, frag, first, len(headerBlock) == 0); err != nil {
+			return err
+		}
+		first = false
+	}
+	return nil
+}
+
+// writeResHeaders is a request to write a HEADERS and 0+ CONTINUATION frames
+// for HTTP response headers or trailers from a server handler.
+type http2writeResHeaders struct {
+	streamID    uint32
+	httpResCode int      // 0 means no ":status" line
+	h           Header   // may be nil
+	trailers    []string // if non-nil, which keys of h to write. nil means all.
+	endStream   bool
+
+	date          string
+	contentType   string
+	contentLength string
+}
+
+func http2encKV(enc *hpack.Encoder, k, v string) {
+	if http2VerboseLogs {
+		log.Printf("http2: server encoding header %q = %q", k, v)
+	}
+	enc.WriteField(hpack.HeaderField{Name: k, Value: v})
+}
+
+func (w *http2writeResHeaders) staysWithinBuffer(max int) bool {
+	// TODO: this is a common one. It'd be nice to return true
+	// here and get into the fast path if we could be clever and
+	// calculate the size fast enough, or at least a conservative
+	// upper bound that usually fires. (Maybe if w.h and
+	// w.trailers are nil, so we don't need to enumerate it.)
+	// Otherwise I'm afraid that just calculating the length to
+	// answer this question would be slower than the ~2µs benefit.
+	return false
+}
+
+func (w *http2writeResHeaders) writeFrame(ctx http2writeContext) error {
+	enc, buf := ctx.HeaderEncoder()
+	buf.Reset()
+
+	if w.httpResCode != 0 {
+		http2encKV(enc, ":status", http2httpCodeString(w.httpResCode))
+	}
+
+	http2encodeHeaders(enc, w.h, w.trailers)
+
+	if w.contentType != "" {
+		http2encKV(enc, "content-type", w.contentType)
+	}
+	if w.contentLength != "" {
+		http2encKV(enc, "content-length", w.contentLength)
+	}
+	if w.date != "" {
+		http2encKV(enc, "date", w.date)
+	}
+
+	headerBlock := buf.Bytes()
+	if len(headerBlock) == 0 && w.trailers == nil {
+		panic("unexpected empty hpack")
+	}
+
+	return http2splitHeaderBlock(ctx, headerBlock, w.writeHeaderBlock)
+}
+
+func (w *http2writeResHeaders) writeHeaderBlock(ctx http2writeContext, frag []byte, firstFrag, lastFrag bool) error {
+	if firstFrag {
+		return ctx.Framer().WriteHeaders(http2HeadersFrameParam{
+			StreamID:      w.streamID,
+			BlockFragment: frag,
+			EndStream:     w.endStream,
+			EndHeaders:    lastFrag,
+		})
+	} else {
+		return ctx.Framer().WriteContinuation(w.streamID, lastFrag, frag)
+	}
+}
+
+// writePushPromise is a request to write a PUSH_PROMISE and 0+ CONTINUATION frames.
+type http2writePushPromise struct {
+	streamID uint32   // pusher stream
+	method   string   // for :method
+	url      *url.URL // for :scheme, :authority, :path
+	h        Header
+
+	// Creates an ID for a pushed stream. This runs on serveG just before
+	// the frame is written. The returned ID is copied to promisedID.
+	allocatePromisedID func() (uint32, error)
+	promisedID         uint32
+}
+
+func (w *http2writePushPromise) staysWithinBuffer(max int) bool {
+	// TODO: see writeResHeaders.staysWithinBuffer
+	return false
+}
+
+func (w *http2writePushPromise) writeFrame(ctx http2writeContext) error {
+	enc, buf := ctx.HeaderEncoder()
+	buf.Reset()
+
+	http2encKV(enc, ":method", w.method)
+	http2encKV(enc, ":scheme", w.url.Scheme)
+	http2encKV(enc, ":authority", w.url.Host)
+	http2encKV(enc, ":path", w.url.RequestURI())
+	http2encodeHeaders(enc, w.h, nil)
+
+	headerBlock := buf.Bytes()
+	if len(headerBlock) == 0 {
+		panic("unexpected empty hpack")
+	}
+
+	return http2splitHeaderBlock(ctx, headerBlock, w.writeHeaderBlock)
+}
+
+func (w *http2writePushPromise) writeHeaderBlock(ctx http2writeContext, frag []byte, firstFrag, lastFrag bool) error {
+	if firstFrag {
+		return ctx.Framer().WritePushPromise(http2PushPromiseParam{
+			StreamID:      w.streamID,
+			PromiseID:     w.promisedID,
+			BlockFragment: frag,
+			EndHeaders:    lastFrag,
+		})
+	} else {
+		return ctx.Framer().WriteContinuation(w.streamID, lastFrag, frag)
+	}
+}
+
+type http2write100ContinueHeadersFrame struct {
+	streamID uint32
+}
+
+func (w http2write100ContinueHeadersFrame) writeFrame(ctx http2writeContext) error {
+	enc, buf := ctx.HeaderEncoder()
+	buf.Reset()
+	http2encKV(enc, ":status", "100")
+	return ctx.Framer().WriteHeaders(http2HeadersFrameParam{
+		StreamID:      w.streamID,
+		BlockFragment: buf.Bytes(),
+		EndStream:     false,
+		EndHeaders:    true,
+	})
+}
+
+func (w http2write100ContinueHeadersFrame) staysWithinBuffer(max int) bool {
+	// Sloppy but conservative:
+	return 9+2*(len(":status")+len("100")) <= max
+}
+
+type http2writeWindowUpdate struct {
+	streamID uint32 // or 0 for conn-level
+	n        uint32
+}
+
+func (wu http2writeWindowUpdate) staysWithinBuffer(max int) bool { return http2frameHeaderLen+4 <= max }
+
+func (wu http2writeWindowUpdate) writeFrame(ctx http2writeContext) error {
+	return ctx.Framer().WriteWindowUpdate(wu.streamID, wu.n)
+}
+
+// encodeHeaders encodes an http.Header. If keys is not nil, then (k, h[k])
+// is encoded only if k is in keys.
+func http2encodeHeaders(enc *hpack.Encoder, h Header, keys []string) {
+	if keys == nil {
+		sorter := http2sorterPool.Get().(*http2sorter)
+		// Using defer here, since the returned keys from the
+		// sorter.Keys method is only valid until the sorter
+		// is returned:
+		defer http2sorterPool.Put(sorter)
+		keys = sorter.Keys(h)
+	}
+	for _, k := range keys {
+		vv := h[k]
+		k, ascii := http2lowerHeader(k)
+		if !ascii {
+			// Skip writing invalid headers. Per RFC 7540, Section 8.1.2, header
+			// field names have to be ASCII characters (just as in HTTP/1.x).
+			continue
+		}
+		if !http2validWireHeaderFieldName(k) {
+			// Skip it as backup paranoia. Per
+			// golang.org/issue/14048, these should
+			// already be rejected at a higher level.
+			continue
+		}
+		isTE := k == "transfer-encoding"
+		for _, v := range vv {
+			if !httpguts.ValidHeaderFieldValue(v) {
+				// TODO: return an error? golang.org/issue/14048
+				// For now just omit it.
+				continue
+			}
+			// TODO: more of "8.1.2.2 Connection-Specific Header Fields"
+			if isTE && v != "trailers" {
+				continue
+			}
+			http2encKV(enc, k, v)
+		}
+	}
+}
+
+// WriteScheduler is the interface implemented by HTTP/2 write schedulers.
+// Methods are never called concurrently.
+type http2WriteScheduler interface {
+	// OpenStream opens a new stream in the write scheduler.
+	// It is illegal to call this with streamID=0 or with a streamID that is
+	// already open -- the call may panic.
+	OpenStream(streamID uint32, options http2OpenStreamOptions)
+
+	// CloseStream closes a stream in the write scheduler. Any frames queued on
+	// this stream should be discarded. It is illegal to call this on a stream
+	// that is not open -- the call may panic.
+	CloseStream(streamID uint32)
+
+	// AdjustStream adjusts the priority of the given stream. This may be called
+	// on a stream that has not yet been opened or has been closed. Note that
+	// RFC 7540 allows PRIORITY frames to be sent on streams in any state. See:
+	// https://tools.ietf.org/html/rfc7540#section-5.1
+	AdjustStream(streamID uint32, priority http2PriorityParam)
+
+	// Push queues a frame in the scheduler. In most cases, this will not be
+	// called with wr.StreamID()!=0 unless that stream is currently open. The one
+	// exception is RST_STREAM frames, which may be sent on idle or closed streams.
+	Push(wr http2FrameWriteRequest)
+
+	// Pop dequeues the next frame to write. Returns false if no frames can
+	// be written. Frames with a given wr.StreamID() are Pop'd in the same
+	// order they are Push'd, except RST_STREAM frames. No frames should be
+	// discarded except by CloseStream.
+	Pop() (wr http2FrameWriteRequest, ok bool)
+}
+
+// OpenStreamOptions specifies extra options for WriteScheduler.OpenStream.
+type http2OpenStreamOptions struct {
+	// PusherID is zero if the stream was initiated by the client. Otherwise,
+	// PusherID names the stream that pushed the newly opened stream.
+	PusherID uint32
+}
+
+// FrameWriteRequest is a request to write a frame.
+type http2FrameWriteRequest struct {
+	// write is the interface value that does the writing, once the
+	// WriteScheduler has selected this frame to write. The write
+	// functions are all defined in write.go.
+	write http2writeFramer
+
+	// stream is the stream on which this frame will be written.
+	// nil for non-stream frames like PING and SETTINGS.
+	// nil for RST_STREAM streams, which use the StreamError.StreamID field instead.
+	stream *http2stream
+
+	// done, if non-nil, must be a buffered channel with space for
+	// 1 message and is sent the return value from write (or an
+	// earlier error) when the frame has been written.
+	done chan error
+}
+
+// StreamID returns the id of the stream this frame will be written to.
+// 0 is used for non-stream frames such as PING and SETTINGS.
+func (wr http2FrameWriteRequest) StreamID() uint32 {
+	if wr.stream == nil {
+		if se, ok := wr.write.(http2StreamError); ok {
+			// (*serverConn).resetStream doesn't set
+			// stream because it doesn't necessarily have
+			// one. So special case this type of write
+			// message.
+			return se.StreamID
+		}
+		return 0
+	}
+	return wr.stream.id
+}
+
+// isControl reports whether wr is a control frame for MaxQueuedControlFrames
+// purposes. That includes non-stream frames and RST_STREAM frames.
+func (wr http2FrameWriteRequest) isControl() bool {
+	return wr.stream == nil
+}
+
+// DataSize returns the number of flow control bytes that must be consumed
+// to write this entire frame. This is 0 for non-DATA frames.
+func (wr http2FrameWriteRequest) DataSize() int {
+	if wd, ok := wr.write.(*http2writeData); ok {
+		return len(wd.p)
+	}
+	return 0
+}
+
+// Consume consumes min(n, available) bytes from this frame, where available
+// is the number of flow control bytes available on the stream. Consume returns
+// 0, 1, or 2 frames, where the integer return value gives the number of frames
+// returned.
+//
+// If flow control prevents consuming any bytes, this returns (_, _, 0). If
+// the entire frame was consumed, this returns (wr, _, 1). Otherwise, this
+// returns (consumed, rest, 2), where 'consumed' contains the consumed bytes and
+// 'rest' contains the remaining bytes. The consumed bytes are deducted from the
+// underlying stream's flow control budget.
+func (wr http2FrameWriteRequest) Consume(n int32) (http2FrameWriteRequest, http2FrameWriteRequest, int) {
+	var empty http2FrameWriteRequest
+
+	// Non-DATA frames are always consumed whole.
+	wd, ok := wr.write.(*http2writeData)
+	if !ok || len(wd.p) == 0 {
+		return wr, empty, 1
+	}
+
+	// Might need to split after applying limits.
+	allowed := wr.stream.flow.available()
+	if n < allowed {
+		allowed = n
+	}
+	if wr.stream.sc.maxFrameSize < allowed {
+		allowed = wr.stream.sc.maxFrameSize
+	}
+	if allowed <= 0 {
+		return empty, empty, 0
+	}
+	if len(wd.p) > int(allowed) {
+		wr.stream.flow.take(allowed)
+		consumed := http2FrameWriteRequest{
+			stream: wr.stream,
+			write: &http2writeData{
+				streamID: wd.streamID,
+				p:        wd.p[:allowed],
+				// Even if the original had endStream set, there
+				// are bytes remaining because len(wd.p) > allowed,
+				// so we know endStream is false.
+				endStream: false,
+			},
+			// Our caller is blocking on the final DATA frame, not
+			// this intermediate frame, so no need to wait.
+			done: nil,
+		}
+		rest := http2FrameWriteRequest{
+			stream: wr.stream,
+			write: &http2writeData{
+				streamID:  wd.streamID,
+				p:         wd.p[allowed:],
+				endStream: wd.endStream,
+			},
+			done: wr.done,
+		}
+		return consumed, rest, 2
+	}
+
+	// The frame is consumed whole.
+	// NB: This cast cannot overflow because allowed is <= math.MaxInt32.
+	wr.stream.flow.take(int32(len(wd.p)))
+	return wr, empty, 1
+}
+
+// String is for debugging only.
+func (wr http2FrameWriteRequest) String() string {
+	var des string
+	if s, ok := wr.write.(fmt.Stringer); ok {
+		des = s.String()
+	} else {
+		des = fmt.Sprintf("%T", wr.write)
+	}
+	return fmt.Sprintf("[FrameWriteRequest stream=%d, ch=%v, writer=%v]", wr.StreamID(), wr.done != nil, des)
+}
+
+// replyToWriter sends err to wr.done and panics if the send must block
+// This does nothing if wr.done is nil.
+func (wr *http2FrameWriteRequest) replyToWriter(err error) {
+	if wr.done == nil {
+		return
+	}
+	select {
+	case wr.done <- err:
+	default:
+		panic(fmt.Sprintf("unbuffered done channel passed in for type %T", wr.write))
+	}
+	wr.write = nil // prevent use (assume it's tainted after wr.done send)
+}
+
+// writeQueue is used by implementations of WriteScheduler.
+type http2writeQueue struct {
+	s []http2FrameWriteRequest
+}
+
+func (q *http2writeQueue) empty() bool { return len(q.s) == 0 }
+
+func (q *http2writeQueue) push(wr http2FrameWriteRequest) {
+	q.s = append(q.s, wr)
+}
+
+func (q *http2writeQueue) shift() http2FrameWriteRequest {
+	if len(q.s) == 0 {
+		panic("invalid use of queue")
+	}
+	wr := q.s[0]
+	// TODO: less copy-happy queue.
+	copy(q.s, q.s[1:])
+	q.s[len(q.s)-1] = http2FrameWriteRequest{}
+	q.s = q.s[:len(q.s)-1]
+	return wr
+}
+
+// consume consumes up to n bytes from q.s[0]. If the frame is
+// entirely consumed, it is removed from the queue. If the frame
+// is partially consumed, the frame is kept with the consumed
+// bytes removed. Returns true iff any bytes were consumed.
+func (q *http2writeQueue) consume(n int32) (http2FrameWriteRequest, bool) {
+	if len(q.s) == 0 {
+		return http2FrameWriteRequest{}, false
+	}
+	consumed, rest, numresult := q.s[0].Consume(n)
+	switch numresult {
+	case 0:
+		return http2FrameWriteRequest{}, false
+	case 1:
+		q.shift()
+	case 2:
+		q.s[0] = rest
+	}
+	return consumed, true
+}
+
+type http2writeQueuePool []*http2writeQueue
+
+// put inserts an unused writeQueue into the pool.
+
+// put inserts an unused writeQueue into the pool.
+func (p *http2writeQueuePool) put(q *http2writeQueue) {
+	for i := range q.s {
+		q.s[i] = http2FrameWriteRequest{}
+	}
+	q.s = q.s[:0]
+	*p = append(*p, q)
+}
+
+// get returns an empty writeQueue.
+func (p *http2writeQueuePool) get() *http2writeQueue {
+	ln := len(*p)
+	if ln == 0 {
+		return new(http2writeQueue)
+	}
+	x := ln - 1
+	q := (*p)[x]
+	(*p)[x] = nil
+	*p = (*p)[:x]
+	return q
+}
+
+// RFC 7540, Section 5.3.5: the default weight is 16.
+const http2priorityDefaultWeight = 15 // 16 = 15 + 1
+
+// PriorityWriteSchedulerConfig configures a priorityWriteScheduler.
+type http2PriorityWriteSchedulerConfig struct {
+	// MaxClosedNodesInTree controls the maximum number of closed streams to
+	// retain in the priority tree. Setting this to zero saves a small amount
+	// of memory at the cost of performance.
+	//
+	// See RFC 7540, Section 5.3.4:
+	//   "It is possible for a stream to become closed while prioritization
+	//   information ... is in transit. ... This potentially creates suboptimal
+	//   prioritization, since the stream could be given a priority that is
+	//   different from what is intended. To avoid these problems, an endpoint
+	//   SHOULD retain stream prioritization state for a period after streams
+	//   become closed. The longer state is retained, the lower the chance that
+	//   streams are assigned incorrect or default priority values."
+	MaxClosedNodesInTree int
+
+	// MaxIdleNodesInTree controls the maximum number of idle streams to
+	// retain in the priority tree. Setting this to zero saves a small amount
+	// of memory at the cost of performance.
+	//
+	// See RFC 7540, Section 5.3.4:
+	//   Similarly, streams that are in the "idle" state can be assigned
+	//   priority or become a parent of other streams. This allows for the
+	//   creation of a grouping node in the dependency tree, which enables
+	//   more flexible expressions of priority. Idle streams begin with a
+	//   default priority (Section 5.3.5).
+	MaxIdleNodesInTree int
+
+	// ThrottleOutOfOrderWrites enables write throttling to help ensure that
+	// data is delivered in priority order. This works around a race where
+	// stream B depends on stream A and both streams are about to call Write
+	// to queue DATA frames. If B wins the race, a naive scheduler would eagerly
+	// write as much data from B as possible, but this is suboptimal because A
+	// is a higher-priority stream. With throttling enabled, we write a small
+	// amount of data from B to minimize the amount of bandwidth that B can
+	// steal from A.
+	ThrottleOutOfOrderWrites bool
+}
+
+// NewPriorityWriteScheduler constructs a WriteScheduler that schedules
+// frames by following HTTP/2 priorities as described in RFC 7540 Section 5.3.
+// If cfg is nil, default options are used.
+func http2NewPriorityWriteScheduler(cfg *http2PriorityWriteSchedulerConfig) http2WriteScheduler {
+	if cfg == nil {
+		// For justification of these defaults, see:
+		// https://docs.google.com/document/d/1oLhNg1skaWD4_DtaoCxdSRN5erEXrH-KnLrMwEpOtFY
+		cfg = &http2PriorityWriteSchedulerConfig{
+			MaxClosedNodesInTree:     10,
+			MaxIdleNodesInTree:       10,
+			ThrottleOutOfOrderWrites: false,
+		}
+	}
+
+	ws := &http2priorityWriteScheduler{
+		nodes:                make(map[uint32]*http2priorityNode),
+		maxClosedNodesInTree: cfg.MaxClosedNodesInTree,
+		maxIdleNodesInTree:   cfg.MaxIdleNodesInTree,
+		enableWriteThrottle:  cfg.ThrottleOutOfOrderWrites,
+	}
+	ws.nodes[0] = &ws.root
+	if cfg.ThrottleOutOfOrderWrites {
+		ws.writeThrottleLimit = 1024
+	} else {
+		ws.writeThrottleLimit = math.MaxInt32
+	}
+	return ws
+}
+
+type http2priorityNodeState int
+
+const (
+	http2priorityNodeOpen http2priorityNodeState = iota
+	http2priorityNodeClosed
+	http2priorityNodeIdle
+)
+
+// priorityNode is a node in an HTTP/2 priority tree.
+// Each node is associated with a single stream ID.
+// See RFC 7540, Section 5.3.
+type http2priorityNode struct {
+	q            http2writeQueue        // queue of pending frames to write
+	id           uint32                 // id of the stream, or 0 for the root of the tree
+	weight       uint8                  // the actual weight is weight+1, so the value is in [1,256]
+	state        http2priorityNodeState // open | closed | idle
+	bytes        int64                  // number of bytes written by this node, or 0 if closed
+	subtreeBytes int64                  // sum(node.bytes) of all nodes in this subtree
+
+	// These links form the priority tree.
+	parent     *http2priorityNode
+	kids       *http2priorityNode // start of the kids list
+	prev, next *http2priorityNode // doubly-linked list of siblings
+}
+
+func (n *http2priorityNode) setParent(parent *http2priorityNode) {
+	if n == parent {
+		panic("setParent to self")
+	}
+	if n.parent == parent {
+		return
+	}
+	// Unlink from current parent.
+	if parent := n.parent; parent != nil {
+		if n.prev == nil {
+			parent.kids = n.next
+		} else {
+			n.prev.next = n.next
+		}
+		if n.next != nil {
+			n.next.prev = n.prev
+		}
+	}
+	// Link to new parent.
+	// If parent=nil, remove n from the tree.
+	// Always insert at the head of parent.kids (this is assumed by walkReadyInOrder).
+	n.parent = parent
+	if parent == nil {
+		n.next = nil
+		n.prev = nil
+	} else {
+		n.next = parent.kids
+		n.prev = nil
+		if n.next != nil {
+			n.next.prev = n
+		}
+		parent.kids = n
+	}
+}
+
+func (n *http2priorityNode) addBytes(b int64) {
+	n.bytes += b
+	for ; n != nil; n = n.parent {
+		n.subtreeBytes += b
+	}
+}
+
+// walkReadyInOrder iterates over the tree in priority order, calling f for each node
+// with a non-empty write queue. When f returns true, this function returns true and the
+// walk halts. tmp is used as scratch space for sorting.
+//
+// f(n, openParent) takes two arguments: the node to visit, n, and a bool that is true
+// if any ancestor p of n is still open (ignoring the root node).
+func (n *http2priorityNode) walkReadyInOrder(openParent bool, tmp *[]*http2priorityNode, f func(*http2priorityNode, bool) bool) bool {
+	if !n.q.empty() && f(n, openParent) {
+		return true
+	}
+	if n.kids == nil {
+		return false
+	}
+
+	// Don't consider the root "open" when updating openParent since
+	// we can't send data frames on the root stream (only control frames).
+	if n.id != 0 {
+		openParent = openParent || (n.state == http2priorityNodeOpen)
+	}
+
+	// Common case: only one kid or all kids have the same weight.
+	// Some clients don't use weights; other clients (like web browsers)
+	// use mostly-linear priority trees.
+	w := n.kids.weight
+	needSort := false
+	for k := n.kids.next; k != nil; k = k.next {
+		if k.weight != w {
+			needSort = true
+			break
+		}
+	}
+	if !needSort {
+		for k := n.kids; k != nil; k = k.next {
+			if k.walkReadyInOrder(openParent, tmp, f) {
+				return true
+			}
+		}
+		return false
+	}
+
+	// Uncommon case: sort the child nodes. We remove the kids from the parent,
+	// then re-insert after sorting so we can reuse tmp for future sort calls.
+	*tmp = (*tmp)[:0]
+	for n.kids != nil {
+		*tmp = append(*tmp, n.kids)
+		n.kids.setParent(nil)
+	}
+	sort.Sort(http2sortPriorityNodeSiblings(*tmp))
+	for i := len(*tmp) - 1; i >= 0; i-- {
+		(*tmp)[i].setParent(n) // setParent inserts at the head of n.kids
+	}
+	for k := n.kids; k != nil; k = k.next {
+		if k.walkReadyInOrder(openParent, tmp, f) {
+			return true
+		}
+	}
+	return false
+}
+
+type http2sortPriorityNodeSiblings []*http2priorityNode
+
+func (z http2sortPriorityNodeSiblings) Len() int { return len(z) }
+
+func (z http2sortPriorityNodeSiblings) Swap(i, k int) { z[i], z[k] = z[k], z[i] }
+
+func (z http2sortPriorityNodeSiblings) Less(i, k int) bool {
+	// Prefer the subtree that has sent fewer bytes relative to its weight.
+	// See sections 5.3.2 and 5.3.4.
+	wi, bi := float64(z[i].weight+1), float64(z[i].subtreeBytes)
+	wk, bk := float64(z[k].weight+1), float64(z[k].subtreeBytes)
+	if bi == 0 && bk == 0 {
+		return wi >= wk
+	}
+	if bk == 0 {
+		return false
+	}
+	return bi/bk <= wi/wk
+}
+
+type http2priorityWriteScheduler struct {
+	// root is the root of the priority tree, where root.id = 0.
+	// The root queues control frames that are not associated with any stream.
+	root http2priorityNode
+
+	// nodes maps stream ids to priority tree nodes.
+	nodes map[uint32]*http2priorityNode
+
+	// maxID is the maximum stream id in nodes.
+	maxID uint32
+
+	// lists of nodes that have been closed or are idle, but are kept in
+	// the tree for improved prioritization. When the lengths exceed either
+	// maxClosedNodesInTree or maxIdleNodesInTree, old nodes are discarded.
+	closedNodes, idleNodes []*http2priorityNode
+
+	// From the config.
+	maxClosedNodesInTree int
+	maxIdleNodesInTree   int
+	writeThrottleLimit   int32
+	enableWriteThrottle  bool
+
+	// tmp is scratch space for priorityNode.walkReadyInOrder to reduce allocations.
+	tmp []*http2priorityNode
+
+	// pool of empty queues for reuse.
+	queuePool http2writeQueuePool
+}
+
+func (ws *http2priorityWriteScheduler) OpenStream(streamID uint32, options http2OpenStreamOptions) {
+	// The stream may be currently idle but cannot be opened or closed.
+	if curr := ws.nodes[streamID]; curr != nil {
+		if curr.state != http2priorityNodeIdle {
+			panic(fmt.Sprintf("stream %d already opened", streamID))
+		}
+		curr.state = http2priorityNodeOpen
+		return
+	}
+
+	// RFC 7540, Section 5.3.5:
+	//  "All streams are initially assigned a non-exclusive dependency on stream 0x0.
+	//  Pushed streams initially depend on their associated stream. In both cases,
+	//  streams are assigned a default weight of 16."
+	parent := ws.nodes[options.PusherID]
+	if parent == nil {
+		parent = &ws.root
+	}
+	n := &http2priorityNode{
+		q:      *ws.queuePool.get(),
+		id:     streamID,
+		weight: http2priorityDefaultWeight,
+		state:  http2priorityNodeOpen,
+	}
+	n.setParent(parent)
+	ws.nodes[streamID] = n
+	if streamID > ws.maxID {
+		ws.maxID = streamID
+	}
+}
+
+func (ws *http2priorityWriteScheduler) CloseStream(streamID uint32) {
+	if streamID == 0 {
+		panic("violation of WriteScheduler interface: cannot close stream 0")
+	}
+	if ws.nodes[streamID] == nil {
+		panic(fmt.Sprintf("violation of WriteScheduler interface: unknown stream %d", streamID))
+	}
+	if ws.nodes[streamID].state != http2priorityNodeOpen {
+		panic(fmt.Sprintf("violation of WriteScheduler interface: stream %d already closed", streamID))
+	}
+
+	n := ws.nodes[streamID]
+	n.state = http2priorityNodeClosed
+	n.addBytes(-n.bytes)
+
+	q := n.q
+	ws.queuePool.put(&q)
+	n.q.s = nil
+	if ws.maxClosedNodesInTree > 0 {
+		ws.addClosedOrIdleNode(&ws.closedNodes, ws.maxClosedNodesInTree, n)
+	} else {
+		ws.removeNode(n)
+	}
+}
+
+func (ws *http2priorityWriteScheduler) AdjustStream(streamID uint32, priority http2PriorityParam) {
+	if streamID == 0 {
+		panic("adjustPriority on root")
+	}
+
+	// If streamID does not exist, there are two cases:
+	// - A closed stream that has been removed (this will have ID <= maxID)
+	// - An idle stream that is being used for "grouping" (this will have ID > maxID)
+	n := ws.nodes[streamID]
+	if n == nil {
+		if streamID <= ws.maxID || ws.maxIdleNodesInTree == 0 {
+			return
+		}
+		ws.maxID = streamID
+		n = &http2priorityNode{
+			q:      *ws.queuePool.get(),
+			id:     streamID,
+			weight: http2priorityDefaultWeight,
+			state:  http2priorityNodeIdle,
+		}
+		n.setParent(&ws.root)
+		ws.nodes[streamID] = n
+		ws.addClosedOrIdleNode(&ws.idleNodes, ws.maxIdleNodesInTree, n)
+	}
+
+	// Section 5.3.1: A dependency on a stream that is not currently in the tree
+	// results in that stream being given a default priority (Section 5.3.5).
+	parent := ws.nodes[priority.StreamDep]
+	if parent == nil {
+		n.setParent(&ws.root)
+		n.weight = http2priorityDefaultWeight
+		return
+	}
+
+	// Ignore if the client tries to make a node its own parent.
+	if n == parent {
+		return
+	}
+
+	// Section 5.3.3:
+	//   "If a stream is made dependent on one of its own dependencies, the
+	//   formerly dependent stream is first moved to be dependent on the
+	//   reprioritized stream's previous parent. The moved dependency retains
+	//   its weight."
+	//
+	// That is: if parent depends on n, move parent to depend on n.parent.
+	for x := parent.parent; x != nil; x = x.parent {
+		if x == n {
+			parent.setParent(n.parent)
+			break
+		}
+	}
+
+	// Section 5.3.3: The exclusive flag causes the stream to become the sole
+	// dependency of its parent stream, causing other dependencies to become
+	// dependent on the exclusive stream.
+	if priority.Exclusive {
+		k := parent.kids
+		for k != nil {
+			next := k.next
+			if k != n {
+				k.setParent(n)
+			}
+			k = next
+		}
+	}
+
+	n.setParent(parent)
+	n.weight = priority.Weight
+}
+
+func (ws *http2priorityWriteScheduler) Push(wr http2FrameWriteRequest) {
+	var n *http2priorityNode
+	if id := wr.StreamID(); id == 0 {
+		n = &ws.root
+	} else {
+		n = ws.nodes[id]
+		if n == nil {
+			// id is an idle or closed stream. wr should not be a HEADERS or
+			// DATA frame. However, wr can be a RST_STREAM. In this case, we
+			// push wr onto the root, rather than creating a new priorityNode,
+			// since RST_STREAM is tiny and the stream's priority is unknown
+			// anyway. See issue #17919.
+			if wr.DataSize() > 0 {
+				panic("add DATA on non-open stream")
+			}
+			n = &ws.root
+		}
+	}
+	n.q.push(wr)
+}
+
+func (ws *http2priorityWriteScheduler) Pop() (wr http2FrameWriteRequest, ok bool) {
+	ws.root.walkReadyInOrder(false, &ws.tmp, func(n *http2priorityNode, openParent bool) bool {
+		limit := int32(math.MaxInt32)
+		if openParent {
+			limit = ws.writeThrottleLimit
+		}
+		wr, ok = n.q.consume(limit)
+		if !ok {
+			return false
+		}
+		n.addBytes(int64(wr.DataSize()))
+		// If B depends on A and B continuously has data available but A
+		// does not, gradually increase the throttling limit to allow B to
+		// steal more and more bandwidth from A.
+		if openParent {
+			ws.writeThrottleLimit += 1024
+			if ws.writeThrottleLimit < 0 {
+				ws.writeThrottleLimit = math.MaxInt32
+			}
+		} else if ws.enableWriteThrottle {
+			ws.writeThrottleLimit = 1024
+		}
+		return true
+	})
+	return wr, ok
+}
+
+func (ws *http2priorityWriteScheduler) addClosedOrIdleNode(list *[]*http2priorityNode, maxSize int, n *http2priorityNode) {
+	if maxSize == 0 {
+		return
+	}
+	if len(*list) == maxSize {
+		// Remove the oldest node, then shift left.
+		ws.removeNode((*list)[0])
+		x := (*list)[1:]
+		copy(*list, x)
+		*list = (*list)[:len(x)]
+	}
+	*list = append(*list, n)
+}
+
+func (ws *http2priorityWriteScheduler) removeNode(n *http2priorityNode) {
+	for k := n.kids; k != nil; k = k.next {
+		k.setParent(n.parent)
+	}
+	n.setParent(nil)
+	delete(ws.nodes, n.id)
+}
+
+// NewRandomWriteScheduler constructs a WriteScheduler that ignores HTTP/2
+// priorities. Control frames like SETTINGS and PING are written before DATA
+// frames, but if no control frames are queued and multiple streams have queued
+// HEADERS or DATA frames, Pop selects a ready stream arbitrarily.
+func http2NewRandomWriteScheduler() http2WriteScheduler {
+	return &http2randomWriteScheduler{sq: make(map[uint32]*http2writeQueue)}
+}
+
+type http2randomWriteScheduler struct {
+	// zero are frames not associated with a specific stream.
+	zero http2writeQueue
+
+	// sq contains the stream-specific queues, keyed by stream ID.
+	// When a stream is idle, closed, or emptied, it's deleted
+	// from the map.
+	sq map[uint32]*http2writeQueue
+
+	// pool of empty queues for reuse.
+	queuePool http2writeQueuePool
+}
+
+func (ws *http2randomWriteScheduler) OpenStream(streamID uint32, options http2OpenStreamOptions) {
+	// no-op: idle streams are not tracked
+}
+
+func (ws *http2randomWriteScheduler) CloseStream(streamID uint32) {
+	q, ok := ws.sq[streamID]
+	if !ok {
+		return
+	}
+	delete(ws.sq, streamID)
+	ws.queuePool.put(q)
+}
+
+func (ws *http2randomWriteScheduler) AdjustStream(streamID uint32, priority http2PriorityParam) {
+	// no-op: priorities are ignored
+}
+
+func (ws *http2randomWriteScheduler) Push(wr http2FrameWriteRequest) {
+	if wr.isControl() {
+		ws.zero.push(wr)
+		return
+	}
+	id := wr.StreamID()
+	q, ok := ws.sq[id]
+	if !ok {
+		q = ws.queuePool.get()
+		ws.sq[id] = q
+	}
+	q.push(wr)
+}
+
+func (ws *http2randomWriteScheduler) Pop() (http2FrameWriteRequest, bool) {
+	// Control and RST_STREAM frames first.
+	if !ws.zero.empty() {
+		return ws.zero.shift(), true
+	}
+	// Iterate over all non-idle streams until finding one that can be consumed.
+	for streamID, q := range ws.sq {
+		if wr, ok := q.consume(math.MaxInt32); ok {
+			if q.empty() {
+				delete(ws.sq, streamID)
+				ws.queuePool.put(q)
+			}
+			return wr, true
+		}
+	}
+	return http2FrameWriteRequest{}, false
+}
diff --git a/contrib/go/_std_1.19/src/net/http/header.go b/contrib/go/_std_1.19/src/net/http/header.go
new file mode 100644
index 0000000000..e0b342c63c
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/http/header.go
@@ -0,0 +1,280 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package http
+
+import (
+	"io"
+	"net/http/httptrace"
+	"net/http/internal/ascii"
+	"net/textproto"
+	"sort"
+	"strings"
+	"sync"
+	"time"
+
+	"golang.org/x/net/http/httpguts"
+)
+
+// A Header represents the key-value pairs in an HTTP header.
+//
+// The keys should be in canonical form, as returned by
+// CanonicalHeaderKey.
+type Header map[string][]string
+
+// Add adds the key, value pair to the header.
+// It appends to any existing values associated with key.
+// The key is case insensitive; it is canonicalized by
+// CanonicalHeaderKey.
+func (h Header) Add(key, value string) {
+	textproto.MIMEHeader(h).Add(key, value)
+}
+
+// Set sets the header entries associated with key to the
+// single element value. It replaces any existing values
+// associated with key. The key is case insensitive; it is
+// canonicalized by textproto.CanonicalMIMEHeaderKey.
+// To use non-canonical keys, assign to the map directly.
+func (h Header) Set(key, value string) {
+	textproto.MIMEHeader(h).Set(key, value)
+}
+
+// Get gets the first value associated with the given key. If
+// there are no values associated with the key, Get returns "".
+// It is case insensitive; textproto.CanonicalMIMEHeaderKey is
+// used to canonicalize the provided key. Get assumes that all
+// keys are stored in canonical form. To use non-canonical keys,
+// access the map directly.
+func (h Header) Get(key string) string {
+	return textproto.MIMEHeader(h).Get(key)
+}
+
+// Values returns all values associated with the given key.
+// It is case insensitive; textproto.CanonicalMIMEHeaderKey is
+// used to canonicalize the provided key. To use non-canonical
+// keys, access the map directly.
+// The returned slice is not a copy.
+func (h Header) Values(key string) []string {
+	return textproto.MIMEHeader(h).Values(key)
+}
+
+// get is like Get, but key must already be in CanonicalHeaderKey form.
+func (h Header) get(key string) string {
+	if v := h[key]; len(v) > 0 {
+		return v[0]
+	}
+	return ""
+}
+
+// has reports whether h has the provided key defined, even if it's
+// set to 0-length slice.
+func (h Header) has(key string) bool {
+	_, ok := h[key]
+	return ok
+}
+
+// Del deletes the values associated with key.
+// The key is case insensitive; it is canonicalized by
+// CanonicalHeaderKey.
+func (h Header) Del(key string) {
+	textproto.MIMEHeader(h).Del(key)
+}
+
+// Write writes a header in wire format.
+func (h Header) Write(w io.Writer) error {
+	return h.write(w, nil)
+}
+
+func (h Header) write(w io.Writer, trace *httptrace.ClientTrace) error {
+	return h.writeSubset(w, nil, trace)
+}
+
+// Clone returns a copy of h or nil if h is nil.
+func (h Header) Clone() Header {
+	if h == nil {
+		return nil
+	}
+
+	// Find total number of values.
+	nv := 0
+	for _, vv := range h {
+		nv += len(vv)
+	}
+	sv := make([]string, nv) // shared backing array for headers' values
+	h2 := make(Header, len(h))
+	for k, vv := range h {
+		if vv == nil {
+			// Preserve nil values. ReverseProxy distinguishes
+			// between nil and zero-length header values.
+			h2[k] = nil
+			continue
+		}
+		n := copy(sv, vv)
+		h2[k] = sv[:n:n]
+		sv = sv[n:]
+	}
+	return h2
+}
+
+var timeFormats = []string{
+	TimeFormat,
+	time.RFC850,
+	time.ANSIC,
+}
+
+// ParseTime parses a time header (such as the Date: header),
+// trying each of the three formats allowed by HTTP/1.1:
+// TimeFormat, time.RFC850, and time.ANSIC.
+func ParseTime(text string) (t time.Time, err error) {
+	for _, layout := range timeFormats {
+		t, err = time.Parse(layout, text)
+		if err == nil {
+			return
+		}
+	}
+	return
+}
+
+var headerNewlineToSpace = strings.NewReplacer("\n", " ", "\r", " ")
+
+// stringWriter implements WriteString on a Writer.
+type stringWriter struct {
+	w io.Writer
+}
+
+func (w stringWriter) WriteString(s string) (n int, err error) {
+	return w.w.Write([]byte(s))
+}
+
+type keyValues struct {
+	key    string
+	values []string
+}
+
+// A headerSorter implements sort.Interface by sorting a []keyValues
+// by key. It's used as a pointer, so it can fit in a sort.Interface
+// interface value without allocation.
+type headerSorter struct {
+	kvs []keyValues
+}
+
+func (s *headerSorter) Len() int           { return len(s.kvs) }
+func (s *headerSorter) Swap(i, j int)      { s.kvs[i], s.kvs[j] = s.kvs[j], s.kvs[i] }
+func (s *headerSorter) Less(i, j int) bool { return s.kvs[i].key < s.kvs[j].key }
+
+var headerSorterPool = sync.Pool{
+	New: func() any { return new(headerSorter) },
+}
+
+// sortedKeyValues returns h's keys sorted in the returned kvs
+// slice. The headerSorter used to sort is also returned, for possible
+// return to headerSorterCache.
+func (h Header) sortedKeyValues(exclude map[string]bool) (kvs []keyValues, hs *headerSorter) {
+	hs = headerSorterPool.Get().(*headerSorter)
+	if cap(hs.kvs) < len(h) {
+		hs.kvs = make([]keyValues, 0, len(h))
+	}
+	kvs = hs.kvs[:0]
+	for k, vv := range h {
+		if !exclude[k] {
+			kvs = append(kvs, keyValues{k, vv})
+		}
+	}
+	hs.kvs = kvs
+	sort.Sort(hs)
+	return kvs, hs
+}
+
+// WriteSubset writes a header in wire format.
+// If exclude is not nil, keys where exclude[key] == true are not written.
+// Keys are not canonicalized before checking the exclude map.
+func (h Header) WriteSubset(w io.Writer, exclude map[string]bool) error {
+	return h.writeSubset(w, exclude, nil)
+}
+
+func (h Header) writeSubset(w io.Writer, exclude map[string]bool, trace *httptrace.ClientTrace) error {
+	ws, ok := w.(io.StringWriter)
+	if !ok {
+		ws = stringWriter{w}
+	}
+	kvs, sorter := h.sortedKeyValues(exclude)
+	var formattedVals []string
+	for _, kv := range kvs {
+		if !httpguts.ValidHeaderFieldName(kv.key) {
+			// This could be an error. In the common case of
+			// writing response headers, however, we have no good
+			// way to provide the error back to the server
+			// handler, so just drop invalid headers instead.
+			continue
+		}
+		for _, v := range kv.values {
+			v = headerNewlineToSpace.Replace(v)
+			v = textproto.TrimString(v)
+			for _, s := range []string{kv.key, ": ", v, "\r\n"} {
+				if _, err := ws.WriteString(s); err != nil {
+					headerSorterPool.Put(sorter)
+					return err
+				}
+			}
+			if trace != nil && trace.WroteHeaderField != nil {
+				formattedVals = append(formattedVals, v)
+			}
+		}
+		if trace != nil && trace.WroteHeaderField != nil {
+			trace.WroteHeaderField(kv.key, formattedVals)
+			formattedVals = nil
+		}
+	}
+	headerSorterPool.Put(sorter)
+	return nil
+}
+
+// CanonicalHeaderKey returns the canonical format of the
+// header key s. The canonicalization converts the first
+// letter and any letter following a hyphen to upper case;
+// the rest are converted to lowercase. For example, the
+// canonical key for "accept-encoding" is "Accept-Encoding".
+// If s contains a space or invalid header field bytes, it is
+// returned without modifications.
+func CanonicalHeaderKey(s string) string { return textproto.CanonicalMIMEHeaderKey(s) }
+
+// hasToken reports whether token appears with v, ASCII
+// case-insensitive, with space or comma boundaries.
+// token must be all lowercase.
+// v may contain mixed cased.
+func hasToken(v, token string) bool {
+	if len(token) > len(v) || token == "" {
+		return false
+	}
+	if v == token {
+		return true
+	}
+	for sp := 0; sp <= len(v)-len(token); sp++ {
+		// Check that first character is good.
+		// The token is ASCII, so checking only a single byte
+		// is sufficient. We skip this potential starting
+		// position if both the first byte and its potential
+		// ASCII uppercase equivalent (b|0x20) don't match.
+		// False positives ('^' => '~') are caught by EqualFold.
+		if b := v[sp]; b != token[0] && b|0x20 != token[0] {
+			continue
+		}
+		// Check that start pos is on a valid token boundary.
+		if sp > 0 && !isTokenBoundary(v[sp-1]) {
+			continue
+		}
+		// Check that end pos is on a valid token boundary.
+		if endPos := sp + len(token); endPos != len(v) && !isTokenBoundary(v[endPos]) {
+			continue
+		}
+		if ascii.EqualFold(v[sp:sp+len(token)], token) {
+			return true
+		}
+	}
+	return false
+}
+
+func isTokenBoundary(b byte) bool {
+	return b == ' ' || b == ',' || b == '\t'
+}
diff --git a/contrib/go/_std_1.18/src/net/http/http.go b/contrib/go/_std_1.19/src/net/http/http.go
index 101799f574..101799f574 100644
--- a/contrib/go/_std_1.18/src/net/http/http.go
+++ b/contrib/go/_std_1.19/src/net/http/http.go
diff --git a/contrib/go/_std_1.18/src/net/http/httptrace/trace.go b/contrib/go/_std_1.19/src/net/http/httptrace/trace.go
index 6af30f78d1..6af30f78d1 100644
--- a/contrib/go/_std_1.18/src/net/http/httptrace/trace.go
+++ b/contrib/go/_std_1.19/src/net/http/httptrace/trace.go
diff --git a/contrib/go/_std_1.18/src/net/http/internal/ascii/print.go b/contrib/go/_std_1.19/src/net/http/internal/ascii/print.go
index 585e5baba4..585e5baba4 100644
--- a/contrib/go/_std_1.18/src/net/http/internal/ascii/print.go
+++ b/contrib/go/_std_1.19/src/net/http/internal/ascii/print.go
diff --git a/contrib/go/_std_1.19/src/net/http/internal/chunked.go b/contrib/go/_std_1.19/src/net/http/internal/chunked.go
new file mode 100644
index 0000000000..5a174415dc
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/http/internal/chunked.go
@@ -0,0 +1,262 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// The wire protocol for HTTP's "chunked" Transfer-Encoding.
+
+// Package internal contains HTTP internals shared by net/http and
+// net/http/httputil.
+package internal
+
+import (
+	"bufio"
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+)
+
+const maxLineLength = 4096 // assumed <= bufio.defaultBufSize
+
+var ErrLineTooLong = errors.New("header line too long")
+
+// NewChunkedReader returns a new chunkedReader that translates the data read from r
+// out of HTTP "chunked" format before returning it.
+// The chunkedReader returns io.EOF when the final 0-length chunk is read.
+//
+// NewChunkedReader is not needed by normal applications. The http package
+// automatically decodes chunking when reading response bodies.
+func NewChunkedReader(r io.Reader) io.Reader {
+	br, ok := r.(*bufio.Reader)
+	if !ok {
+		br = bufio.NewReader(r)
+	}
+	return &chunkedReader{r: br}
+}
+
+type chunkedReader struct {
+	r        *bufio.Reader
+	n        uint64 // unread bytes in chunk
+	err      error
+	buf      [2]byte
+	checkEnd bool // whether need to check for \r\n chunk footer
+}
+
+func (cr *chunkedReader) beginChunk() {
+	// chunk-size CRLF
+	var line []byte
+	line, cr.err = readChunkLine(cr.r)
+	if cr.err != nil {
+		return
+	}
+	cr.n, cr.err = parseHexUint(line)
+	if cr.err != nil {
+		return
+	}
+	if cr.n == 0 {
+		cr.err = io.EOF
+	}
+}
+
+func (cr *chunkedReader) chunkHeaderAvailable() bool {
+	n := cr.r.Buffered()
+	if n > 0 {
+		peek, _ := cr.r.Peek(n)
+		return bytes.IndexByte(peek, '\n') >= 0
+	}
+	return false
+}
+
+func (cr *chunkedReader) Read(b []uint8) (n int, err error) {
+	for cr.err == nil {
+		if cr.checkEnd {
+			if n > 0 && cr.r.Buffered() < 2 {
+				// We have some data. Return early (per the io.Reader
+				// contract) instead of potentially blocking while
+				// reading more.
+				break
+			}
+			if _, cr.err = io.ReadFull(cr.r, cr.buf[:2]); cr.err == nil {
+				if string(cr.buf[:]) != "\r\n" {
+					cr.err = errors.New("malformed chunked encoding")
+					break
+				}
+			} else {
+				if cr.err == io.EOF {
+					cr.err = io.ErrUnexpectedEOF
+				}
+				break
+			}
+			cr.checkEnd = false
+		}
+		if cr.n == 0 {
+			if n > 0 && !cr.chunkHeaderAvailable() {
+				// We've read enough. Don't potentially block
+				// reading a new chunk header.
+				break
+			}
+			cr.beginChunk()
+			continue
+		}
+		if len(b) == 0 {
+			break
+		}
+		rbuf := b
+		if uint64(len(rbuf)) > cr.n {
+			rbuf = rbuf[:cr.n]
+		}
+		var n0 int
+		n0, cr.err = cr.r.Read(rbuf)
+		n += n0
+		b = b[n0:]
+		cr.n -= uint64(n0)
+		// If we're at the end of a chunk, read the next two
+		// bytes to verify they are "\r\n".
+		if cr.n == 0 && cr.err == nil {
+			cr.checkEnd = true
+		} else if cr.err == io.EOF {
+			cr.err = io.ErrUnexpectedEOF
+		}
+	}
+	return n, cr.err
+}
+
+// Read a line of bytes (up to \n) from b.
+// Give up if the line exceeds maxLineLength.
+// The returned bytes are owned by the bufio.Reader
+// so they are only valid until the next bufio read.
+func readChunkLine(b *bufio.Reader) ([]byte, error) {
+	p, err := b.ReadSlice('\n')
+	if err != nil {
+		// We always know when EOF is coming.
+		// If the caller asked for a line, there should be a line.
+		if err == io.EOF {
+			err = io.ErrUnexpectedEOF
+		} else if err == bufio.ErrBufferFull {
+			err = ErrLineTooLong
+		}
+		return nil, err
+	}
+	if len(p) >= maxLineLength {
+		return nil, ErrLineTooLong
+	}
+	p = trimTrailingWhitespace(p)
+	p, err = removeChunkExtension(p)
+	if err != nil {
+		return nil, err
+	}
+	return p, nil
+}
+
+func trimTrailingWhitespace(b []byte) []byte {
+	for len(b) > 0 && isASCIISpace(b[len(b)-1]) {
+		b = b[:len(b)-1]
+	}
+	return b
+}
+
+func isASCIISpace(b byte) bool {
+	return b == ' ' || b == '\t' || b == '\n' || b == '\r'
+}
+
+var semi = []byte(";")
+
+// removeChunkExtension removes any chunk-extension from p.
+// For example,
+//
+//	"0" => "0"
+//	"0;token" => "0"
+//	"0;token=val" => "0"
+//	`0;token="quoted string"` => "0"
+func removeChunkExtension(p []byte) ([]byte, error) {
+	p, _, _ = bytes.Cut(p, semi)
+	// TODO: care about exact syntax of chunk extensions? We're
+	// ignoring and stripping them anyway. For now just never
+	// return an error.
+	return p, nil
+}
+
+// NewChunkedWriter returns a new chunkedWriter that translates writes into HTTP
+// "chunked" format before writing them to w. Closing the returned chunkedWriter
+// sends the final 0-length chunk that marks the end of the stream but does
+// not send the final CRLF that appears after trailers; trailers and the last
+// CRLF must be written separately.
+//
+// NewChunkedWriter is not needed by normal applications. The http
+// package adds chunking automatically if handlers don't set a
+// Content-Length header. Using newChunkedWriter inside a handler
+// would result in double chunking or chunking with a Content-Length
+// length, both of which are wrong.
+func NewChunkedWriter(w io.Writer) io.WriteCloser {
+	return &chunkedWriter{w}
+}
+
+// Writing to chunkedWriter translates to writing in HTTP chunked Transfer
+// Encoding wire format to the underlying Wire chunkedWriter.
+type chunkedWriter struct {
+	Wire io.Writer
+}
+
+// Write the contents of data as one chunk to Wire.
+// NOTE: Note that the corresponding chunk-writing procedure in Conn.Write has
+// a bug since it does not check for success of io.WriteString
+func (cw *chunkedWriter) Write(data []byte) (n int, err error) {
+
+	// Don't send 0-length data. It looks like EOF for chunked encoding.
+	if len(data) == 0 {
+		return 0, nil
+	}
+
+	if _, err = fmt.Fprintf(cw.Wire, "%x\r\n", len(data)); err != nil {
+		return 0, err
+	}
+	if n, err = cw.Wire.Write(data); err != nil {
+		return
+	}
+	if n != len(data) {
+		err = io.ErrShortWrite
+		return
+	}
+	if _, err = io.WriteString(cw.Wire, "\r\n"); err != nil {
+		return
+	}
+	if bw, ok := cw.Wire.(*FlushAfterChunkWriter); ok {
+		err = bw.Flush()
+	}
+	return
+}
+
+func (cw *chunkedWriter) Close() error {
+	_, err := io.WriteString(cw.Wire, "0\r\n")
+	return err
+}
+
+// FlushAfterChunkWriter signals from the caller of NewChunkedWriter
+// that each chunk should be followed by a flush. It is used by the
+// http.Transport code to keep the buffering behavior for headers and
+// trailers, but flush out chunks aggressively in the middle for
+// request bodies which may be generated slowly. See Issue 6574.
+type FlushAfterChunkWriter struct {
+	*bufio.Writer
+}
+
+func parseHexUint(v []byte) (n uint64, err error) {
+	for i, b := range v {
+		switch {
+		case '0' <= b && b <= '9':
+			b = b - '0'
+		case 'a' <= b && b <= 'f':
+			b = b - 'a' + 10
+		case 'A' <= b && b <= 'F':
+			b = b - 'A' + 10
+		default:
+			return 0, errors.New("invalid byte in chunk length")
+		}
+		if i == 16 {
+			return 0, errors.New("http chunk length too large")
+		}
+		n <<= 4
+		n |= uint64(b)
+	}
+	return
+}
diff --git a/contrib/go/_std_1.18/src/net/http/jar.go b/contrib/go/_std_1.19/src/net/http/jar.go
index 5c3de0dad2..5c3de0dad2 100644
--- a/contrib/go/_std_1.18/src/net/http/jar.go
+++ b/contrib/go/_std_1.19/src/net/http/jar.go
diff --git a/contrib/go/_std_1.18/src/net/http/method.go b/contrib/go/_std_1.19/src/net/http/method.go
index 6f46155069..6f46155069 100644
--- a/contrib/go/_std_1.18/src/net/http/method.go
+++ b/contrib/go/_std_1.19/src/net/http/method.go
diff --git a/contrib/go/_std_1.19/src/net/http/request.go b/contrib/go/_std_1.19/src/net/http/request.go
new file mode 100644
index 0000000000..cead91d3d4
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/http/request.go
@@ -0,0 +1,1483 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// HTTP Request reading and parsing.
+
+package http
+
+import (
+	"bufio"
+	"bytes"
+	"context"
+	"crypto/tls"
+	"encoding/base64"
+	"errors"
+	"fmt"
+	"io"
+	"mime"
+	"mime/multipart"
+	"net"
+	"net/http/httptrace"
+	"net/http/internal/ascii"
+	"net/textproto"
+	"net/url"
+	urlpkg "net/url"
+	"strconv"
+	"strings"
+	"sync"
+
+	"golang.org/x/net/idna"
+)
+
+const (
+	defaultMaxMemory = 32 << 20 // 32 MB
+)
+
+// ErrMissingFile is returned by FormFile when the provided file field name
+// is either not present in the request or not a file field.
+var ErrMissingFile = errors.New("http: no such file")
+
+// ProtocolError represents an HTTP protocol error.
+//
+// Deprecated: Not all errors in the http package related to protocol errors
+// are of type ProtocolError.
+type ProtocolError struct {
+	ErrorString string
+}
+
+func (pe *ProtocolError) Error() string { return pe.ErrorString }
+
+var (
+	// ErrNotSupported is returned by the Push method of Pusher
+	// implementations to indicate that HTTP/2 Push support is not
+	// available.
+	ErrNotSupported = &ProtocolError{"feature not supported"}
+
+	// Deprecated: ErrUnexpectedTrailer is no longer returned by
+	// anything in the net/http package. Callers should not
+	// compare errors against this variable.
+	ErrUnexpectedTrailer = &ProtocolError{"trailer header without chunked transfer encoding"}
+
+	// ErrMissingBoundary is returned by Request.MultipartReader when the
+	// request's Content-Type does not include a "boundary" parameter.
+	ErrMissingBoundary = &ProtocolError{"no multipart boundary param in Content-Type"}
+
+	// ErrNotMultipart is returned by Request.MultipartReader when the
+	// request's Content-Type is not multipart/form-data.
+	ErrNotMultipart = &ProtocolError{"request Content-Type isn't multipart/form-data"}
+
+	// Deprecated: ErrHeaderTooLong is no longer returned by
+	// anything in the net/http package. Callers should not
+	// compare errors against this variable.
+	ErrHeaderTooLong = &ProtocolError{"header too long"}
+
+	// Deprecated: ErrShortBody is no longer returned by
+	// anything in the net/http package. Callers should not
+	// compare errors against this variable.
+	ErrShortBody = &ProtocolError{"entity body too short"}
+
+	// Deprecated: ErrMissingContentLength is no longer returned by
+	// anything in the net/http package. Callers should not
+	// compare errors against this variable.
+	ErrMissingContentLength = &ProtocolError{"missing ContentLength in HEAD response"}
+)
+
+func badStringError(what, val string) error { return fmt.Errorf("%s %q", what, val) }
+
+// Headers that Request.Write handles itself and should be skipped.
+var reqWriteExcludeHeader = map[string]bool{
+	"Host":              true, // not in Header map anyway
+	"User-Agent":        true,
+	"Content-Length":    true,
+	"Transfer-Encoding": true,
+	"Trailer":           true,
+}
+
+// A Request represents an HTTP request received by a server
+// or to be sent by a client.
+//
+// The field semantics differ slightly between client and server
+// usage. In addition to the notes on the fields below, see the
+// documentation for Request.Write and RoundTripper.
+type Request struct {
+	// Method specifies the HTTP method (GET, POST, PUT, etc.).
+	// For client requests, an empty string means GET.
+	//
+	// Go's HTTP client does not support sending a request with
+	// the CONNECT method. See the documentation on Transport for
+	// details.
+	Method string
+
+	// URL specifies either the URI being requested (for server
+	// requests) or the URL to access (for client requests).
+	//
+	// For server requests, the URL is parsed from the URI
+	// supplied on the Request-Line as stored in RequestURI.  For
+	// most requests, fields other than Path and RawQuery will be
+	// empty. (See RFC 7230, Section 5.3)
+	//
+	// For client requests, the URL's Host specifies the server to
+	// connect to, while the Request's Host field optionally
+	// specifies the Host header value to send in the HTTP
+	// request.
+	URL *url.URL
+
+	// The protocol version for incoming server requests.
+	//
+	// For client requests, these fields are ignored. The HTTP
+	// client code always uses either HTTP/1.1 or HTTP/2.
+	// See the docs on Transport for details.
+	Proto      string // "HTTP/1.0"
+	ProtoMajor int    // 1
+	ProtoMinor int    // 0
+
+	// Header contains the request header fields either received
+	// by the server or to be sent by the client.
+	//
+	// If a server received a request with header lines,
+	//
+	//	Host: example.com
+	//	accept-encoding: gzip, deflate
+	//	Accept-Language: en-us
+	//	fOO: Bar
+	//	foo: two
+	//
+	// then
+	//
+	//	Header = map[string][]string{
+	//		"Accept-Encoding": {"gzip, deflate"},
+	//		"Accept-Language": {"en-us"},
+	//		"Foo": {"Bar", "two"},
+	//	}
+	//
+	// For incoming requests, the Host header is promoted to the
+	// Request.Host field and removed from the Header map.
+	//
+	// HTTP defines that header names are case-insensitive. The
+	// request parser implements this by using CanonicalHeaderKey,
+	// making the first character and any characters following a
+	// hyphen uppercase and the rest lowercase.
+	//
+	// For client requests, certain headers such as Content-Length
+	// and Connection are automatically written when needed and
+	// values in Header may be ignored. See the documentation
+	// for the Request.Write method.
+	Header Header
+
+	// Body is the request's body.
+	//
+	// For client requests, a nil body means the request has no
+	// body, such as a GET request. The HTTP Client's Transport
+	// is responsible for calling the Close method.
+	//
+	// For server requests, the Request Body is always non-nil
+	// but will return EOF immediately when no body is present.
+	// The Server will close the request body. The ServeHTTP
+	// Handler does not need to.
+	//
+	// Body must allow Read to be called concurrently with Close.
+	// In particular, calling Close should unblock a Read waiting
+	// for input.
+	Body io.ReadCloser
+
+	// GetBody defines an optional func to return a new copy of
+	// Body. It is used for client requests when a redirect requires
+	// reading the body more than once. Use of GetBody still
+	// requires setting Body.
+	//
+	// For server requests, it is unused.
+	GetBody func() (io.ReadCloser, error)
+
+	// ContentLength records the length of the associated content.
+	// The value -1 indicates that the length is unknown.
+	// Values >= 0 indicate that the given number of bytes may
+	// be read from Body.
+	//
+	// For client requests, a value of 0 with a non-nil Body is
+	// also treated as unknown.
+	ContentLength int64
+
+	// TransferEncoding lists the transfer encodings from outermost to
+	// innermost. An empty list denotes the "identity" encoding.
+	// TransferEncoding can usually be ignored; chunked encoding is
+	// automatically added and removed as necessary when sending and
+	// receiving requests.
+	TransferEncoding []string
+
+	// Close indicates whether to close the connection after
+	// replying to this request (for servers) or after sending this
+	// request and reading its response (for clients).
+	//
+	// For server requests, the HTTP server handles this automatically
+	// and this field is not needed by Handlers.
+	//
+	// For client requests, setting this field prevents re-use of
+	// TCP connections between requests to the same hosts, as if
+	// Transport.DisableKeepAlives were set.
+	Close bool
+
+	// For server requests, Host specifies the host on which the
+	// URL is sought. For HTTP/1 (per RFC 7230, section 5.4), this
+	// is either the value of the "Host" header or the host name
+	// given in the URL itself. For HTTP/2, it is the value of the
+	// ":authority" pseudo-header field.
+	// It may be of the form "host:port". For international domain
+	// names, Host may be in Punycode or Unicode form. Use
+	// golang.org/x/net/idna to convert it to either format if
+	// needed.
+	// To prevent DNS rebinding attacks, server Handlers should
+	// validate that the Host header has a value for which the
+	// Handler considers itself authoritative. The included
+	// ServeMux supports patterns registered to particular host
+	// names and thus protects its registered Handlers.
+	//
+	// For client requests, Host optionally overrides the Host
+	// header to send. If empty, the Request.Write method uses
+	// the value of URL.Host. Host may contain an international
+	// domain name.
+	Host string
+
+	// Form contains the parsed form data, including both the URL
+	// field's query parameters and the PATCH, POST, or PUT form data.
+	// This field is only available after ParseForm is called.
+	// The HTTP client ignores Form and uses Body instead.
+	Form url.Values
+
+	// PostForm contains the parsed form data from PATCH, POST
+	// or PUT body parameters.
+	//
+	// This field is only available after ParseForm is called.
+	// The HTTP client ignores PostForm and uses Body instead.
+	PostForm url.Values
+
+	// MultipartForm is the parsed multipart form, including file uploads.
+	// This field is only available after ParseMultipartForm is called.
+	// The HTTP client ignores MultipartForm and uses Body instead.
+	MultipartForm *multipart.Form
+
+	// Trailer specifies additional headers that are sent after the request
+	// body.
+	//
+	// For server requests, the Trailer map initially contains only the
+	// trailer keys, with nil values. (The client declares which trailers it
+	// will later send.)  While the handler is reading from Body, it must
+	// not reference Trailer. After reading from Body returns EOF, Trailer
+	// can be read again and will contain non-nil values, if they were sent
+	// by the client.
+	//
+	// For client requests, Trailer must be initialized to a map containing
+	// the trailer keys to later send. The values may be nil or their final
+	// values. The ContentLength must be 0 or -1, to send a chunked request.
+	// After the HTTP request is sent the map values can be updated while
+	// the request body is read. Once the body returns EOF, the caller must
+	// not mutate Trailer.
+	//
+	// Few HTTP clients, servers, or proxies support HTTP trailers.
+	Trailer Header
+
+	// RemoteAddr allows HTTP servers and other software to record
+	// the network address that sent the request, usually for
+	// logging. This field is not filled in by ReadRequest and
+	// has no defined format. The HTTP server in this package
+	// sets RemoteAddr to an "IP:port" address before invoking a
+	// handler.
+	// This field is ignored by the HTTP client.
+	RemoteAddr string
+
+	// RequestURI is the unmodified request-target of the
+	// Request-Line (RFC 7230, Section 3.1.1) as sent by the client
+	// to a server. Usually the URL field should be used instead.
+	// It is an error to set this field in an HTTP client request.
+	RequestURI string
+
+	// TLS allows HTTP servers and other software to record
+	// information about the TLS connection on which the request
+	// was received. This field is not filled in by ReadRequest.
+	// The HTTP server in this package sets the field for
+	// TLS-enabled connections before invoking a handler;
+	// otherwise it leaves the field nil.
+	// This field is ignored by the HTTP client.
+	TLS *tls.ConnectionState
+
+	// Cancel is an optional channel whose closure indicates that the client
+	// request should be regarded as canceled. Not all implementations of
+	// RoundTripper may support Cancel.
+	//
+	// For server requests, this field is not applicable.
+	//
+	// Deprecated: Set the Request's context with NewRequestWithContext
+	// instead. If a Request's Cancel field and context are both
+	// set, it is undefined whether Cancel is respected.
+	Cancel <-chan struct{}
+
+	// Response is the redirect response which caused this request
+	// to be created. This field is only populated during client
+	// redirects.
+	Response *Response
+
+	// ctx is either the client or server context. It should only
+	// be modified via copying the whole Request using WithContext.
+	// It is unexported to prevent people from using Context wrong
+	// and mutating the contexts held by callers of the same request.
+	ctx context.Context
+}
+
+// Context returns the request's context. To change the context, use
+// WithContext.
+//
+// The returned context is always non-nil; it defaults to the
+// background context.
+//
+// For outgoing client requests, the context controls cancellation.
+//
+// For incoming server requests, the context is canceled when the
+// client's connection closes, the request is canceled (with HTTP/2),
+// or when the ServeHTTP method returns.
+func (r *Request) Context() context.Context {
+	if r.ctx != nil {
+		return r.ctx
+	}
+	return context.Background()
+}
+
+// WithContext returns a shallow copy of r with its context changed
+// to ctx. The provided ctx must be non-nil.
+//
+// For outgoing client request, the context controls the entire
+// lifetime of a request and its response: obtaining a connection,
+// sending the request, and reading the response headers and body.
+//
+// To create a new request with a context, use NewRequestWithContext.
+// To change the context of a request, such as an incoming request you
+// want to modify before sending back out, use Request.Clone. Between
+// those two uses, it's rare to need WithContext.
+func (r *Request) WithContext(ctx context.Context) *Request {
+	if ctx == nil {
+		panic("nil context")
+	}
+	r2 := new(Request)
+	*r2 = *r
+	r2.ctx = ctx
+	return r2
+}
+
+// Clone returns a deep copy of r with its context changed to ctx.
+// The provided ctx must be non-nil.
+//
+// For an outgoing client request, the context controls the entire
+// lifetime of a request and its response: obtaining a connection,
+// sending the request, and reading the response headers and body.
+func (r *Request) Clone(ctx context.Context) *Request {
+	if ctx == nil {
+		panic("nil context")
+	}
+	r2 := new(Request)
+	*r2 = *r
+	r2.ctx = ctx
+	r2.URL = cloneURL(r.URL)
+	if r.Header != nil {
+		r2.Header = r.Header.Clone()
+	}
+	if r.Trailer != nil {
+		r2.Trailer = r.Trailer.Clone()
+	}
+	if s := r.TransferEncoding; s != nil {
+		s2 := make([]string, len(s))
+		copy(s2, s)
+		r2.TransferEncoding = s2
+	}
+	r2.Form = cloneURLValues(r.Form)
+	r2.PostForm = cloneURLValues(r.PostForm)
+	r2.MultipartForm = cloneMultipartForm(r.MultipartForm)
+	return r2
+}
+
+// ProtoAtLeast reports whether the HTTP protocol used
+// in the request is at least major.minor.
+func (r *Request) ProtoAtLeast(major, minor int) bool {
+	return r.ProtoMajor > major ||
+		r.ProtoMajor == major && r.ProtoMinor >= minor
+}
+
+// UserAgent returns the client's User-Agent, if sent in the request.
+func (r *Request) UserAgent() string {
+	return r.Header.Get("User-Agent")
+}
+
+// Cookies parses and returns the HTTP cookies sent with the request.
+func (r *Request) Cookies() []*Cookie {
+	return readCookies(r.Header, "")
+}
+
+// ErrNoCookie is returned by Request's Cookie method when a cookie is not found.
+var ErrNoCookie = errors.New("http: named cookie not present")
+
+// Cookie returns the named cookie provided in the request or
+// ErrNoCookie if not found.
+// If multiple cookies match the given name, only one cookie will
+// be returned.
+func (r *Request) Cookie(name string) (*Cookie, error) {
+	for _, c := range readCookies(r.Header, name) {
+		return c, nil
+	}
+	return nil, ErrNoCookie
+}
+
+// AddCookie adds a cookie to the request. Per RFC 6265 section 5.4,
+// AddCookie does not attach more than one Cookie header field. That
+// means all cookies, if any, are written into the same line,
+// separated by semicolon.
+// AddCookie only sanitizes c's name and value, and does not sanitize
+// a Cookie header already present in the request.
+func (r *Request) AddCookie(c *Cookie) {
+	s := fmt.Sprintf("%s=%s", sanitizeCookieName(c.Name), sanitizeCookieValue(c.Value))
+	if c := r.Header.Get("Cookie"); c != "" {
+		r.Header.Set("Cookie", c+"; "+s)
+	} else {
+		r.Header.Set("Cookie", s)
+	}
+}
+
+// Referer returns the referring URL, if sent in the request.
+//
+// Referer is misspelled as in the request itself, a mistake from the
+// earliest days of HTTP.  This value can also be fetched from the
+// Header map as Header["Referer"]; the benefit of making it available
+// as a method is that the compiler can diagnose programs that use the
+// alternate (correct English) spelling req.Referrer() but cannot
+// diagnose programs that use Header["Referrer"].
+func (r *Request) Referer() string {
+	return r.Header.Get("Referer")
+}
+
+// multipartByReader is a sentinel value.
+// Its presence in Request.MultipartForm indicates that parsing of the request
+// body has been handed off to a MultipartReader instead of ParseMultipartForm.
+var multipartByReader = &multipart.Form{
+	Value: make(map[string][]string),
+	File:  make(map[string][]*multipart.FileHeader),
+}
+
+// MultipartReader returns a MIME multipart reader if this is a
+// multipart/form-data or a multipart/mixed POST request, else returns nil and an error.
+// Use this function instead of ParseMultipartForm to
+// process the request body as a stream.
+func (r *Request) MultipartReader() (*multipart.Reader, error) {
+	if r.MultipartForm == multipartByReader {
+		return nil, errors.New("http: MultipartReader called twice")
+	}
+	if r.MultipartForm != nil {
+		return nil, errors.New("http: multipart handled by ParseMultipartForm")
+	}
+	r.MultipartForm = multipartByReader
+	return r.multipartReader(true)
+}
+
+func (r *Request) multipartReader(allowMixed bool) (*multipart.Reader, error) {
+	v := r.Header.Get("Content-Type")
+	if v == "" {
+		return nil, ErrNotMultipart
+	}
+	if r.Body == nil {
+		return nil, errors.New("missing form body")
+	}
+	d, params, err := mime.ParseMediaType(v)
+	if err != nil || !(d == "multipart/form-data" || allowMixed && d == "multipart/mixed") {
+		return nil, ErrNotMultipart
+	}
+	boundary, ok := params["boundary"]
+	if !ok {
+		return nil, ErrMissingBoundary
+	}
+	return multipart.NewReader(r.Body, boundary), nil
+}
+
+// isH2Upgrade reports whether r represents the http2 "client preface"
+// magic string.
+func (r *Request) isH2Upgrade() bool {
+	return r.Method == "PRI" && len(r.Header) == 0 && r.URL.Path == "*" && r.Proto == "HTTP/2.0"
+}
+
+// Return value if nonempty, def otherwise.
+func valueOrDefault(value, def string) string {
+	if value != "" {
+		return value
+	}
+	return def
+}
+
+// NOTE: This is not intended to reflect the actual Go version being used.
+// It was changed at the time of Go 1.1 release because the former User-Agent
+// had ended up blocked by some intrusion detection systems.
+// See https://codereview.appspot.com/7532043.
+const defaultUserAgent = "Go-http-client/1.1"
+
+// Write writes an HTTP/1.1 request, which is the header and body, in wire format.
+// This method consults the following fields of the request:
+//
+//	Host
+//	URL
+//	Method (defaults to "GET")
+//	Header
+//	ContentLength
+//	TransferEncoding
+//	Body
+//
+// If Body is present, Content-Length is <= 0 and TransferEncoding
+// hasn't been set to "identity", Write adds "Transfer-Encoding:
+// chunked" to the header. Body is closed after it is sent.
+func (r *Request) Write(w io.Writer) error {
+	return r.write(w, false, nil, nil)
+}
+
+// WriteProxy is like Write but writes the request in the form
+// expected by an HTTP proxy. In particular, WriteProxy writes the
+// initial Request-URI line of the request with an absolute URI, per
+// section 5.3 of RFC 7230, including the scheme and host.
+// In either case, WriteProxy also writes a Host header, using
+// either r.Host or r.URL.Host.
+func (r *Request) WriteProxy(w io.Writer) error {
+	return r.write(w, true, nil, nil)
+}
+
+// errMissingHost is returned by Write when there is no Host or URL present in
+// the Request.
+var errMissingHost = errors.New("http: Request.Write on Request with no Host or URL set")
+
+// extraHeaders may be nil
+// waitForContinue may be nil
+// always closes body
+func (r *Request) write(w io.Writer, usingProxy bool, extraHeaders Header, waitForContinue func() bool) (err error) {
+	trace := httptrace.ContextClientTrace(r.Context())
+	if trace != nil && trace.WroteRequest != nil {
+		defer func() {
+			trace.WroteRequest(httptrace.WroteRequestInfo{
+				Err: err,
+			})
+		}()
+	}
+	closed := false
+	defer func() {
+		if closed {
+			return
+		}
+		if closeErr := r.closeBody(); closeErr != nil && err == nil {
+			err = closeErr
+		}
+	}()
+
+	// Find the target host. Prefer the Host: header, but if that
+	// is not given, use the host from the request URL.
+	//
+	// Clean the host, in case it arrives with unexpected stuff in it.
+	host := cleanHost(r.Host)
+	if host == "" {
+		if r.URL == nil {
+			return errMissingHost
+		}
+		host = cleanHost(r.URL.Host)
+	}
+
+	// According to RFC 6874, an HTTP client, proxy, or other
+	// intermediary must remove any IPv6 zone identifier attached
+	// to an outgoing URI.
+	host = removeZone(host)
+
+	ruri := r.URL.RequestURI()
+	if usingProxy && r.URL.Scheme != "" && r.URL.Opaque == "" {
+		ruri = r.URL.Scheme + "://" + host + ruri
+	} else if r.Method == "CONNECT" && r.URL.Path == "" {
+		// CONNECT requests normally give just the host and port, not a full URL.
+		ruri = host
+		if r.URL.Opaque != "" {
+			ruri = r.URL.Opaque
+		}
+	}
+	if stringContainsCTLByte(ruri) {
+		return errors.New("net/http: can't write control character in Request.URL")
+	}
+	// TODO: validate r.Method too? At least it's less likely to
+	// come from an attacker (more likely to be a constant in
+	// code).
+
+	// Wrap the writer in a bufio Writer if it's not already buffered.
+	// Don't always call NewWriter, as that forces a bytes.Buffer
+	// and other small bufio Writers to have a minimum 4k buffer
+	// size.
+	var bw *bufio.Writer
+	if _, ok := w.(io.ByteWriter); !ok {
+		bw = bufio.NewWriter(w)
+		w = bw
+	}
+
+	_, err = fmt.Fprintf(w, "%s %s HTTP/1.1\r\n", valueOrDefault(r.Method, "GET"), ruri)
+	if err != nil {
+		return err
+	}
+
+	// Header lines
+	_, err = fmt.Fprintf(w, "Host: %s\r\n", host)
+	if err != nil {
+		return err
+	}
+	if trace != nil && trace.WroteHeaderField != nil {
+		trace.WroteHeaderField("Host", []string{host})
+	}
+
+	// Use the defaultUserAgent unless the Header contains one, which
+	// may be blank to not send the header.
+	userAgent := defaultUserAgent
+	if r.Header.has("User-Agent") {
+		userAgent = r.Header.Get("User-Agent")
+	}
+	if userAgent != "" {
+		_, err = fmt.Fprintf(w, "User-Agent: %s\r\n", userAgent)
+		if err != nil {
+			return err
+		}
+		if trace != nil && trace.WroteHeaderField != nil {
+			trace.WroteHeaderField("User-Agent", []string{userAgent})
+		}
+	}
+
+	// Process Body,ContentLength,Close,Trailer
+	tw, err := newTransferWriter(r)
+	if err != nil {
+		return err
+	}
+	err = tw.writeHeader(w, trace)
+	if err != nil {
+		return err
+	}
+
+	err = r.Header.writeSubset(w, reqWriteExcludeHeader, trace)
+	if err != nil {
+		return err
+	}
+
+	if extraHeaders != nil {
+		err = extraHeaders.write(w, trace)
+		if err != nil {
+			return err
+		}
+	}
+
+	_, err = io.WriteString(w, "\r\n")
+	if err != nil {
+		return err
+	}
+
+	if trace != nil && trace.WroteHeaders != nil {
+		trace.WroteHeaders()
+	}
+
+	// Flush and wait for 100-continue if expected.
+	if waitForContinue != nil {
+		if bw, ok := w.(*bufio.Writer); ok {
+			err = bw.Flush()
+			if err != nil {
+				return err
+			}
+		}
+		if trace != nil && trace.Wait100Continue != nil {
+			trace.Wait100Continue()
+		}
+		if !waitForContinue() {
+			closed = true
+			r.closeBody()
+			return nil
+		}
+	}
+
+	if bw, ok := w.(*bufio.Writer); ok && tw.FlushHeaders {
+		if err := bw.Flush(); err != nil {
+			return err
+		}
+	}
+
+	// Write body and trailer
+	closed = true
+	err = tw.writeBody(w)
+	if err != nil {
+		if tw.bodyReadError == err {
+			err = requestBodyReadError{err}
+		}
+		return err
+	}
+
+	if bw != nil {
+		return bw.Flush()
+	}
+	return nil
+}
+
+// requestBodyReadError wraps an error from (*Request).write to indicate
+// that the error came from a Read call on the Request.Body.
+// This error type should not escape the net/http package to users.
+type requestBodyReadError struct{ error }
+
+func idnaASCII(v string) (string, error) {
+	// TODO: Consider removing this check after verifying performance is okay.
+	// Right now punycode verification, length checks, context checks, and the
+	// permissible character tests are all omitted. It also prevents the ToASCII
+	// call from salvaging an invalid IDN, when possible. As a result it may be
+	// possible to have two IDNs that appear identical to the user where the
+	// ASCII-only version causes an error downstream whereas the non-ASCII
+	// version does not.
+	// Note that for correct ASCII IDNs ToASCII will only do considerably more
+	// work, but it will not cause an allocation.
+	if ascii.Is(v) {
+		return v, nil
+	}
+	return idna.Lookup.ToASCII(v)
+}
+
+// cleanHost cleans up the host sent in request's Host header.
+//
+// It both strips anything after '/' or ' ', and puts the value
+// into Punycode form, if necessary.
+//
+// Ideally we'd clean the Host header according to the spec:
+//
+//	https://tools.ietf.org/html/rfc7230#section-5.4 (Host = uri-host [ ":" port ]")
+//	https://tools.ietf.org/html/rfc7230#section-2.7 (uri-host -> rfc3986's host)
+//	https://tools.ietf.org/html/rfc3986#section-3.2.2 (definition of host)
+//
+// But practically, what we are trying to avoid is the situation in
+// issue 11206, where a malformed Host header used in the proxy context
+// would create a bad request. So it is enough to just truncate at the
+// first offending character.
+func cleanHost(in string) string {
+	if i := strings.IndexAny(in, " /"); i != -1 {
+		in = in[:i]
+	}
+	host, port, err := net.SplitHostPort(in)
+	if err != nil { // input was just a host
+		a, err := idnaASCII(in)
+		if err != nil {
+			return in // garbage in, garbage out
+		}
+		return a
+	}
+	a, err := idnaASCII(host)
+	if err != nil {
+		return in // garbage in, garbage out
+	}
+	return net.JoinHostPort(a, port)
+}
+
+// removeZone removes IPv6 zone identifier from host.
+// E.g., "[fe80::1%en0]:8080" to "[fe80::1]:8080"
+func removeZone(host string) string {
+	if !strings.HasPrefix(host, "[") {
+		return host
+	}
+	i := strings.LastIndex(host, "]")
+	if i < 0 {
+		return host
+	}
+	j := strings.LastIndex(host[:i], "%")
+	if j < 0 {
+		return host
+	}
+	return host[:j] + host[i:]
+}
+
+// ParseHTTPVersion parses an HTTP version string according to RFC 7230, section 2.6.
+// "HTTP/1.0" returns (1, 0, true). Note that strings without
+// a minor version, such as "HTTP/2", are not valid.
+func ParseHTTPVersion(vers string) (major, minor int, ok bool) {
+	switch vers {
+	case "HTTP/1.1":
+		return 1, 1, true
+	case "HTTP/1.0":
+		return 1, 0, true
+	}
+	if !strings.HasPrefix(vers, "HTTP/") {
+		return 0, 0, false
+	}
+	if len(vers) != len("HTTP/X.Y") {
+		return 0, 0, false
+	}
+	if vers[6] != '.' {
+		return 0, 0, false
+	}
+	maj, err := strconv.ParseUint(vers[5:6], 10, 0)
+	if err != nil {
+		return 0, 0, false
+	}
+	min, err := strconv.ParseUint(vers[7:8], 10, 0)
+	if err != nil {
+		return 0, 0, false
+	}
+	return int(maj), int(min), true
+}
+
+func validMethod(method string) bool {
+	/*
+	     Method         = "OPTIONS"                ; Section 9.2
+	                    | "GET"                    ; Section 9.3
+	                    | "HEAD"                   ; Section 9.4
+	                    | "POST"                   ; Section 9.5
+	                    | "PUT"                    ; Section 9.6
+	                    | "DELETE"                 ; Section 9.7
+	                    | "TRACE"                  ; Section 9.8
+	                    | "CONNECT"                ; Section 9.9
+	                    | extension-method
+	   extension-method = token
+	     token          = 1*<any CHAR except CTLs or separators>
+	*/
+	return len(method) > 0 && strings.IndexFunc(method, isNotToken) == -1
+}
+
+// NewRequest wraps NewRequestWithContext using context.Background.
+func NewRequest(method, url string, body io.Reader) (*Request, error) {
+	return NewRequestWithContext(context.Background(), method, url, body)
+}
+
+// NewRequestWithContext returns a new Request given a method, URL, and
+// optional body.
+//
+// If the provided body is also an io.Closer, the returned
+// Request.Body is set to body and will be closed by the Client
+// methods Do, Post, and PostForm, and Transport.RoundTrip.
+//
+// NewRequestWithContext returns a Request suitable for use with
+// Client.Do or Transport.RoundTrip. To create a request for use with
+// testing a Server Handler, either use the NewRequest function in the
+// net/http/httptest package, use ReadRequest, or manually update the
+// Request fields. For an outgoing client request, the context
+// controls the entire lifetime of a request and its response:
+// obtaining a connection, sending the request, and reading the
+// response headers and body. See the Request type's documentation for
+// the difference between inbound and outbound request fields.
+//
+// If body is of type *bytes.Buffer, *bytes.Reader, or
+// *strings.Reader, the returned request's ContentLength is set to its
+// exact value (instead of -1), GetBody is populated (so 307 and 308
+// redirects can replay the body), and Body is set to NoBody if the
+// ContentLength is 0.
+func NewRequestWithContext(ctx context.Context, method, url string, body io.Reader) (*Request, error) {
+	if method == "" {
+		// We document that "" means "GET" for Request.Method, and people have
+		// relied on that from NewRequest, so keep that working.
+		// We still enforce validMethod for non-empty methods.
+		method = "GET"
+	}
+	if !validMethod(method) {
+		return nil, fmt.Errorf("net/http: invalid method %q", method)
+	}
+	if ctx == nil {
+		return nil, errors.New("net/http: nil Context")
+	}
+	u, err := urlpkg.Parse(url)
+	if err != nil {
+		return nil, err
+	}
+	rc, ok := body.(io.ReadCloser)
+	if !ok && body != nil {
+		rc = io.NopCloser(body)
+	}
+	// The host's colon:port should be normalized. See Issue 14836.
+	u.Host = removeEmptyPort(u.Host)
+	req := &Request{
+		ctx:        ctx,
+		Method:     method,
+		URL:        u,
+		Proto:      "HTTP/1.1",
+		ProtoMajor: 1,
+		ProtoMinor: 1,
+		Header:     make(Header),
+		Body:       rc,
+		Host:       u.Host,
+	}
+	if body != nil {
+		switch v := body.(type) {
+		case *bytes.Buffer:
+			req.ContentLength = int64(v.Len())
+			buf := v.Bytes()
+			req.GetBody = func() (io.ReadCloser, error) {
+				r := bytes.NewReader(buf)
+				return io.NopCloser(r), nil
+			}
+		case *bytes.Reader:
+			req.ContentLength = int64(v.Len())
+			snapshot := *v
+			req.GetBody = func() (io.ReadCloser, error) {
+				r := snapshot
+				return io.NopCloser(&r), nil
+			}
+		case *strings.Reader:
+			req.ContentLength = int64(v.Len())
+			snapshot := *v
+			req.GetBody = func() (io.ReadCloser, error) {
+				r := snapshot
+				return io.NopCloser(&r), nil
+			}
+		default:
+			// This is where we'd set it to -1 (at least
+			// if body != NoBody) to mean unknown, but
+			// that broke people during the Go 1.8 testing
+			// period. People depend on it being 0 I
+			// guess. Maybe retry later. See Issue 18117.
+		}
+		// For client requests, Request.ContentLength of 0
+		// means either actually 0, or unknown. The only way
+		// to explicitly say that the ContentLength is zero is
+		// to set the Body to nil. But turns out too much code
+		// depends on NewRequest returning a non-nil Body,
+		// so we use a well-known ReadCloser variable instead
+		// and have the http package also treat that sentinel
+		// variable to mean explicitly zero.
+		if req.GetBody != nil && req.ContentLength == 0 {
+			req.Body = NoBody
+			req.GetBody = func() (io.ReadCloser, error) { return NoBody, nil }
+		}
+	}
+
+	return req, nil
+}
+
+// BasicAuth returns the username and password provided in the request's
+// Authorization header, if the request uses HTTP Basic Authentication.
+// See RFC 2617, Section 2.
+func (r *Request) BasicAuth() (username, password string, ok bool) {
+	auth := r.Header.Get("Authorization")
+	if auth == "" {
+		return "", "", false
+	}
+	return parseBasicAuth(auth)
+}
+
+// parseBasicAuth parses an HTTP Basic Authentication string.
+// "Basic QWxhZGRpbjpvcGVuIHNlc2FtZQ==" returns ("Aladdin", "open sesame", true).
+func parseBasicAuth(auth string) (username, password string, ok bool) {
+	const prefix = "Basic "
+	// Case insensitive prefix match. See Issue 22736.
+	if len(auth) < len(prefix) || !ascii.EqualFold(auth[:len(prefix)], prefix) {
+		return "", "", false
+	}
+	c, err := base64.StdEncoding.DecodeString(auth[len(prefix):])
+	if err != nil {
+		return "", "", false
+	}
+	cs := string(c)
+	username, password, ok = strings.Cut(cs, ":")
+	if !ok {
+		return "", "", false
+	}
+	return username, password, true
+}
+
+// SetBasicAuth sets the request's Authorization header to use HTTP
+// Basic Authentication with the provided username and password.
+//
+// With HTTP Basic Authentication the provided username and password
+// are not encrypted. It should generally only be used in an HTTPS
+// request.
+//
+// The username may not contain a colon. Some protocols may impose
+// additional requirements on pre-escaping the username and
+// password. For instance, when used with OAuth2, both arguments must
+// be URL encoded first with url.QueryEscape.
+func (r *Request) SetBasicAuth(username, password string) {
+	r.Header.Set("Authorization", "Basic "+basicAuth(username, password))
+}
+
+// parseRequestLine parses "GET /foo HTTP/1.1" into its three parts.
+func parseRequestLine(line string) (method, requestURI, proto string, ok bool) {
+	method, rest, ok1 := strings.Cut(line, " ")
+	requestURI, proto, ok2 := strings.Cut(rest, " ")
+	if !ok1 || !ok2 {
+		return "", "", "", false
+	}
+	return method, requestURI, proto, true
+}
+
+var textprotoReaderPool sync.Pool
+
+func newTextprotoReader(br *bufio.Reader) *textproto.Reader {
+	if v := textprotoReaderPool.Get(); v != nil {
+		tr := v.(*textproto.Reader)
+		tr.R = br
+		return tr
+	}
+	return textproto.NewReader(br)
+}
+
+func putTextprotoReader(r *textproto.Reader) {
+	r.R = nil
+	textprotoReaderPool.Put(r)
+}
+
+// ReadRequest reads and parses an incoming request from b.
+//
+// ReadRequest is a low-level function and should only be used for
+// specialized applications; most code should use the Server to read
+// requests and handle them via the Handler interface. ReadRequest
+// only supports HTTP/1.x requests. For HTTP/2, use golang.org/x/net/http2.
+func ReadRequest(b *bufio.Reader) (*Request, error) {
+	req, err := readRequest(b)
+	if err != nil {
+		return nil, err
+	}
+
+	delete(req.Header, "Host")
+	return req, err
+}
+
+func readRequest(b *bufio.Reader) (req *Request, err error) {
+	tp := newTextprotoReader(b)
+	req = new(Request)
+
+	// First line: GET /index.html HTTP/1.0
+	var s string
+	if s, err = tp.ReadLine(); err != nil {
+		return nil, err
+	}
+	defer func() {
+		putTextprotoReader(tp)
+		if err == io.EOF {
+			err = io.ErrUnexpectedEOF
+		}
+	}()
+
+	var ok bool
+	req.Method, req.RequestURI, req.Proto, ok = parseRequestLine(s)
+	if !ok {
+		return nil, badStringError("malformed HTTP request", s)
+	}
+	if !validMethod(req.Method) {
+		return nil, badStringError("invalid method", req.Method)
+	}
+	rawurl := req.RequestURI
+	if req.ProtoMajor, req.ProtoMinor, ok = ParseHTTPVersion(req.Proto); !ok {
+		return nil, badStringError("malformed HTTP version", req.Proto)
+	}
+
+	// CONNECT requests are used two different ways, and neither uses a full URL:
+	// The standard use is to tunnel HTTPS through an HTTP proxy.
+	// It looks like "CONNECT www.google.com:443 HTTP/1.1", and the parameter is
+	// just the authority section of a URL. This information should go in req.URL.Host.
+	//
+	// The net/rpc package also uses CONNECT, but there the parameter is a path
+	// that starts with a slash. It can be parsed with the regular URL parser,
+	// and the path will end up in req.URL.Path, where it needs to be in order for
+	// RPC to work.
+	justAuthority := req.Method == "CONNECT" && !strings.HasPrefix(rawurl, "/")
+	if justAuthority {
+		rawurl = "http://" + rawurl
+	}
+
+	if req.URL, err = url.ParseRequestURI(rawurl); err != nil {
+		return nil, err
+	}
+
+	if justAuthority {
+		// Strip the bogus "http://" back off.
+		req.URL.Scheme = ""
+	}
+
+	// Subsequent lines: Key: value.
+	mimeHeader, err := tp.ReadMIMEHeader()
+	if err != nil {
+		return nil, err
+	}
+	req.Header = Header(mimeHeader)
+	if len(req.Header["Host"]) > 1 {
+		return nil, fmt.Errorf("too many Host headers")
+	}
+
+	// RFC 7230, section 5.3: Must treat
+	//	GET /index.html HTTP/1.1
+	//	Host: www.google.com
+	// and
+	//	GET http://www.google.com/index.html HTTP/1.1
+	//	Host: doesntmatter
+	// the same. In the second case, any Host line is ignored.
+	req.Host = req.URL.Host
+	if req.Host == "" {
+		req.Host = req.Header.get("Host")
+	}
+
+	fixPragmaCacheControl(req.Header)
+
+	req.Close = shouldClose(req.ProtoMajor, req.ProtoMinor, req.Header, false)
+
+	err = readTransfer(req, b)
+	if err != nil {
+		return nil, err
+	}
+
+	if req.isH2Upgrade() {
+		// Because it's neither chunked, nor declared:
+		req.ContentLength = -1
+
+		// We want to give handlers a chance to hijack the
+		// connection, but we need to prevent the Server from
+		// dealing with the connection further if it's not
+		// hijacked. Set Close to ensure that:
+		req.Close = true
+	}
+	return req, nil
+}
+
+// MaxBytesReader is similar to io.LimitReader but is intended for
+// limiting the size of incoming request bodies. In contrast to
+// io.LimitReader, MaxBytesReader's result is a ReadCloser, returns a
+// non-nil error of type *MaxBytesError for a Read beyond the limit,
+// and closes the underlying reader when its Close method is called.
+//
+// MaxBytesReader prevents clients from accidentally or maliciously
+// sending a large request and wasting server resources. If possible,
+// it tells the ResponseWriter to close the connection after the limit
+// has been reached.
+func MaxBytesReader(w ResponseWriter, r io.ReadCloser, n int64) io.ReadCloser {
+	if n < 0 { // Treat negative limits as equivalent to 0.
+		n = 0
+	}
+	return &maxBytesReader{w: w, r: r, i: n, n: n}
+}
+
+// MaxBytesError is returned by MaxBytesReader when its read limit is exceeded.
+type MaxBytesError struct {
+	Limit int64
+}
+
+func (e *MaxBytesError) Error() string {
+	// Due to Hyrum's law, this text cannot be changed.
+	return "http: request body too large"
+}
+
+type maxBytesReader struct {
+	w   ResponseWriter
+	r   io.ReadCloser // underlying reader
+	i   int64         // max bytes initially, for MaxBytesError
+	n   int64         // max bytes remaining
+	err error         // sticky error
+}
+
+func (l *maxBytesReader) Read(p []byte) (n int, err error) {
+	if l.err != nil {
+		return 0, l.err
+	}
+	if len(p) == 0 {
+		return 0, nil
+	}
+	// If they asked for a 32KB byte read but only 5 bytes are
+	// remaining, no need to read 32KB. 6 bytes will answer the
+	// question of the whether we hit the limit or go past it.
+	if int64(len(p)) > l.n+1 {
+		p = p[:l.n+1]
+	}
+	n, err = l.r.Read(p)
+
+	if int64(n) <= l.n {
+		l.n -= int64(n)
+		l.err = err
+		return n, err
+	}
+
+	n = int(l.n)
+	l.n = 0
+
+	// The server code and client code both use
+	// maxBytesReader. This "requestTooLarge" check is
+	// only used by the server code. To prevent binaries
+	// which only using the HTTP Client code (such as
+	// cmd/go) from also linking in the HTTP server, don't
+	// use a static type assertion to the server
+	// "*response" type. Check this interface instead:
+	type requestTooLarger interface {
+		requestTooLarge()
+	}
+	if res, ok := l.w.(requestTooLarger); ok {
+		res.requestTooLarge()
+	}
+	l.err = &MaxBytesError{l.i}
+	return n, l.err
+}
+
+func (l *maxBytesReader) Close() error {
+	return l.r.Close()
+}
+
+func copyValues(dst, src url.Values) {
+	for k, vs := range src {
+		dst[k] = append(dst[k], vs...)
+	}
+}
+
+func parsePostForm(r *Request) (vs url.Values, err error) {
+	if r.Body == nil {
+		err = errors.New("missing form body")
+		return
+	}
+	ct := r.Header.Get("Content-Type")
+	// RFC 7231, section 3.1.1.5 - empty type
+	//   MAY be treated as application/octet-stream
+	if ct == "" {
+		ct = "application/octet-stream"
+	}
+	ct, _, err = mime.ParseMediaType(ct)
+	switch {
+	case ct == "application/x-www-form-urlencoded":
+		var reader io.Reader = r.Body
+		maxFormSize := int64(1<<63 - 1)
+		if _, ok := r.Body.(*maxBytesReader); !ok {
+			maxFormSize = int64(10 << 20) // 10 MB is a lot of text.
+			reader = io.LimitReader(r.Body, maxFormSize+1)
+		}
+		b, e := io.ReadAll(reader)
+		if e != nil {
+			if err == nil {
+				err = e
+			}
+			break
+		}
+		if int64(len(b)) > maxFormSize {
+			err = errors.New("http: POST too large")
+			return
+		}
+		vs, e = url.ParseQuery(string(b))
+		if err == nil {
+			err = e
+		}
+	case ct == "multipart/form-data":
+		// handled by ParseMultipartForm (which is calling us, or should be)
+		// TODO(bradfitz): there are too many possible
+		// orders to call too many functions here.
+		// Clean this up and write more tests.
+		// request_test.go contains the start of this,
+		// in TestParseMultipartFormOrder and others.
+	}
+	return
+}
+
+// ParseForm populates r.Form and r.PostForm.
+//
+// For all requests, ParseForm parses the raw query from the URL and updates
+// r.Form.
+//
+// For POST, PUT, and PATCH requests, it also reads the request body, parses it
+// as a form and puts the results into both r.PostForm and r.Form. Request body
+// parameters take precedence over URL query string values in r.Form.
+//
+// If the request Body's size has not already been limited by MaxBytesReader,
+// the size is capped at 10MB.
+//
+// For other HTTP methods, or when the Content-Type is not
+// application/x-www-form-urlencoded, the request Body is not read, and
+// r.PostForm is initialized to a non-nil, empty value.
+//
+// ParseMultipartForm calls ParseForm automatically.
+// ParseForm is idempotent.
+func (r *Request) ParseForm() error {
+	var err error
+	if r.PostForm == nil {
+		if r.Method == "POST" || r.Method == "PUT" || r.Method == "PATCH" {
+			r.PostForm, err = parsePostForm(r)
+		}
+		if r.PostForm == nil {
+			r.PostForm = make(url.Values)
+		}
+	}
+	if r.Form == nil {
+		if len(r.PostForm) > 0 {
+			r.Form = make(url.Values)
+			copyValues(r.Form, r.PostForm)
+		}
+		var newValues url.Values
+		if r.URL != nil {
+			var e error
+			newValues, e = url.ParseQuery(r.URL.RawQuery)
+			if err == nil {
+				err = e
+			}
+		}
+		if newValues == nil {
+			newValues = make(url.Values)
+		}
+		if r.Form == nil {
+			r.Form = newValues
+		} else {
+			copyValues(r.Form, newValues)
+		}
+	}
+	return err
+}
+
+// ParseMultipartForm parses a request body as multipart/form-data.
+// The whole request body is parsed and up to a total of maxMemory bytes of
+// its file parts are stored in memory, with the remainder stored on
+// disk in temporary files.
+// ParseMultipartForm calls ParseForm if necessary.
+// If ParseForm returns an error, ParseMultipartForm returns it but also
+// continues parsing the request body.
+// After one call to ParseMultipartForm, subsequent calls have no effect.
+func (r *Request) ParseMultipartForm(maxMemory int64) error {
+	if r.MultipartForm == multipartByReader {
+		return errors.New("http: multipart handled by MultipartReader")
+	}
+	var parseFormErr error
+	if r.Form == nil {
+		// Let errors in ParseForm fall through, and just
+		// return it at the end.
+		parseFormErr = r.ParseForm()
+	}
+	if r.MultipartForm != nil {
+		return nil
+	}
+
+	mr, err := r.multipartReader(false)
+	if err != nil {
+		return err
+	}
+
+	f, err := mr.ReadForm(maxMemory)
+	if err != nil {
+		return err
+	}
+
+	if r.PostForm == nil {
+		r.PostForm = make(url.Values)
+	}
+	for k, v := range f.Value {
+		r.Form[k] = append(r.Form[k], v...)
+		// r.PostForm should also be populated. See Issue 9305.
+		r.PostForm[k] = append(r.PostForm[k], v...)
+	}
+
+	r.MultipartForm = f
+
+	return parseFormErr
+}
+
+// FormValue returns the first value for the named component of the query.
+// POST and PUT body parameters take precedence over URL query string values.
+// FormValue calls ParseMultipartForm and ParseForm if necessary and ignores
+// any errors returned by these functions.
+// If key is not present, FormValue returns the empty string.
+// To access multiple values of the same key, call ParseForm and
+// then inspect Request.Form directly.
+func (r *Request) FormValue(key string) string {
+	if r.Form == nil {
+		r.ParseMultipartForm(defaultMaxMemory)
+	}
+	if vs := r.Form[key]; len(vs) > 0 {
+		return vs[0]
+	}
+	return ""
+}
+
+// PostFormValue returns the first value for the named component of the POST,
+// PATCH, or PUT request body. URL query parameters are ignored.
+// PostFormValue calls ParseMultipartForm and ParseForm if necessary and ignores
+// any errors returned by these functions.
+// If key is not present, PostFormValue returns the empty string.
+func (r *Request) PostFormValue(key string) string {
+	if r.PostForm == nil {
+		r.ParseMultipartForm(defaultMaxMemory)
+	}
+	if vs := r.PostForm[key]; len(vs) > 0 {
+		return vs[0]
+	}
+	return ""
+}
+
+// FormFile returns the first file for the provided form key.
+// FormFile calls ParseMultipartForm and ParseForm if necessary.
+func (r *Request) FormFile(key string) (multipart.File, *multipart.FileHeader, error) {
+	if r.MultipartForm == multipartByReader {
+		return nil, nil, errors.New("http: multipart handled by MultipartReader")
+	}
+	if r.MultipartForm == nil {
+		err := r.ParseMultipartForm(defaultMaxMemory)
+		if err != nil {
+			return nil, nil, err
+		}
+	}
+	if r.MultipartForm != nil && r.MultipartForm.File != nil {
+		if fhs := r.MultipartForm.File[key]; len(fhs) > 0 {
+			f, err := fhs[0].Open()
+			return f, fhs[0], err
+		}
+	}
+	return nil, nil, ErrMissingFile
+}
+
+func (r *Request) expectsContinue() bool {
+	return hasToken(r.Header.get("Expect"), "100-continue")
+}
+
+func (r *Request) wantsHttp10KeepAlive() bool {
+	if r.ProtoMajor != 1 || r.ProtoMinor != 0 {
+		return false
+	}
+	return hasToken(r.Header.get("Connection"), "keep-alive")
+}
+
+func (r *Request) wantsClose() bool {
+	if r.Close {
+		return true
+	}
+	return hasToken(r.Header.get("Connection"), "close")
+}
+
+func (r *Request) closeBody() error {
+	if r.Body == nil {
+		return nil
+	}
+	return r.Body.Close()
+}
+
+func (r *Request) isReplayable() bool {
+	if r.Body == nil || r.Body == NoBody || r.GetBody != nil {
+		switch valueOrDefault(r.Method, "GET") {
+		case "GET", "HEAD", "OPTIONS", "TRACE":
+			return true
+		}
+		// The Idempotency-Key, while non-standard, is widely used to
+		// mean a POST or other request is idempotent. See
+		// https://golang.org/issue/19943#issuecomment-421092421
+		if r.Header.has("Idempotency-Key") || r.Header.has("X-Idempotency-Key") {
+			return true
+		}
+	}
+	return false
+}
+
+// outgoingLength reports the Content-Length of this outgoing (Client) request.
+// It maps 0 into -1 (unknown) when the Body is non-nil.
+func (r *Request) outgoingLength() int64 {
+	if r.Body == nil || r.Body == NoBody {
+		return 0
+	}
+	if r.ContentLength != 0 {
+		return r.ContentLength
+	}
+	return -1
+}
+
+// requestMethodUsuallyLacksBody reports whether the given request
+// method is one that typically does not involve a request body.
+// This is used by the Transport (via
+// transferWriter.shouldSendChunkedRequestBody) to determine whether
+// we try to test-read a byte from a non-nil Request.Body when
+// Request.outgoingLength() returns -1. See the comments in
+// shouldSendChunkedRequestBody.
+func requestMethodUsuallyLacksBody(method string) bool {
+	switch method {
+	case "GET", "HEAD", "DELETE", "OPTIONS", "PROPFIND", "SEARCH":
+		return true
+	}
+	return false
+}
+
+// requiresHTTP1 reports whether this request requires being sent on
+// an HTTP/1 connection.
+func (r *Request) requiresHTTP1() bool {
+	return hasToken(r.Header.Get("Connection"), "upgrade") &&
+		ascii.EqualFold(r.Header.Get("Upgrade"), "websocket")
+}
diff --git a/contrib/go/_std_1.19/src/net/http/response.go b/contrib/go/_std_1.19/src/net/http/response.go
new file mode 100644
index 0000000000..755c696557
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/http/response.go
@@ -0,0 +1,371 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// HTTP Response reading and parsing.
+
+package http
+
+import (
+	"bufio"
+	"bytes"
+	"crypto/tls"
+	"errors"
+	"fmt"
+	"io"
+	"net/textproto"
+	"net/url"
+	"strconv"
+	"strings"
+
+	"golang.org/x/net/http/httpguts"
+)
+
+var respExcludeHeader = map[string]bool{
+	"Content-Length":    true,
+	"Transfer-Encoding": true,
+	"Trailer":           true,
+}
+
+// Response represents the response from an HTTP request.
+//
+// The Client and Transport return Responses from servers once
+// the response headers have been received. The response body
+// is streamed on demand as the Body field is read.
+type Response struct {
+	Status     string // e.g. "200 OK"
+	StatusCode int    // e.g. 200
+	Proto      string // e.g. "HTTP/1.0"
+	ProtoMajor int    // e.g. 1
+	ProtoMinor int    // e.g. 0
+
+	// Header maps header keys to values. If the response had multiple
+	// headers with the same key, they may be concatenated, with comma
+	// delimiters.  (RFC 7230, section 3.2.2 requires that multiple headers
+	// be semantically equivalent to a comma-delimited sequence.) When
+	// Header values are duplicated by other fields in this struct (e.g.,
+	// ContentLength, TransferEncoding, Trailer), the field values are
+	// authoritative.
+	//
+	// Keys in the map are canonicalized (see CanonicalHeaderKey).
+	Header Header
+
+	// Body represents the response body.
+	//
+	// The response body is streamed on demand as the Body field
+	// is read. If the network connection fails or the server
+	// terminates the response, Body.Read calls return an error.
+	//
+	// The http Client and Transport guarantee that Body is always
+	// non-nil, even on responses without a body or responses with
+	// a zero-length body. It is the caller's responsibility to
+	// close Body. The default HTTP client's Transport may not
+	// reuse HTTP/1.x "keep-alive" TCP connections if the Body is
+	// not read to completion and closed.
+	//
+	// The Body is automatically dechunked if the server replied
+	// with a "chunked" Transfer-Encoding.
+	//
+	// As of Go 1.12, the Body will also implement io.Writer
+	// on a successful "101 Switching Protocols" response,
+	// as used by WebSockets and HTTP/2's "h2c" mode.
+	Body io.ReadCloser
+
+	// ContentLength records the length of the associated content. The
+	// value -1 indicates that the length is unknown. Unless Request.Method
+	// is "HEAD", values >= 0 indicate that the given number of bytes may
+	// be read from Body.
+	ContentLength int64
+
+	// Contains transfer encodings from outer-most to inner-most. Value is
+	// nil, means that "identity" encoding is used.
+	TransferEncoding []string
+
+	// Close records whether the header directed that the connection be
+	// closed after reading Body. The value is advice for clients: neither
+	// ReadResponse nor Response.Write ever closes a connection.
+	Close bool
+
+	// Uncompressed reports whether the response was sent compressed but
+	// was decompressed by the http package. When true, reading from
+	// Body yields the uncompressed content instead of the compressed
+	// content actually set from the server, ContentLength is set to -1,
+	// and the "Content-Length" and "Content-Encoding" fields are deleted
+	// from the responseHeader. To get the original response from
+	// the server, set Transport.DisableCompression to true.
+	Uncompressed bool
+
+	// Trailer maps trailer keys to values in the same
+	// format as Header.
+	//
+	// The Trailer initially contains only nil values, one for
+	// each key specified in the server's "Trailer" header
+	// value. Those values are not added to Header.
+	//
+	// Trailer must not be accessed concurrently with Read calls
+	// on the Body.
+	//
+	// After Body.Read has returned io.EOF, Trailer will contain
+	// any trailer values sent by the server.
+	Trailer Header
+
+	// Request is the request that was sent to obtain this Response.
+	// Request's Body is nil (having already been consumed).
+	// This is only populated for Client requests.
+	Request *Request
+
+	// TLS contains information about the TLS connection on which the
+	// response was received. It is nil for unencrypted responses.
+	// The pointer is shared between responses and should not be
+	// modified.
+	TLS *tls.ConnectionState
+}
+
+// Cookies parses and returns the cookies set in the Set-Cookie headers.
+func (r *Response) Cookies() []*Cookie {
+	return readSetCookies(r.Header)
+}
+
+// ErrNoLocation is returned by Response's Location method
+// when no Location header is present.
+var ErrNoLocation = errors.New("http: no Location header in response")
+
+// Location returns the URL of the response's "Location" header,
+// if present. Relative redirects are resolved relative to
+// the Response's Request. ErrNoLocation is returned if no
+// Location header is present.
+func (r *Response) Location() (*url.URL, error) {
+	lv := r.Header.Get("Location")
+	if lv == "" {
+		return nil, ErrNoLocation
+	}
+	if r.Request != nil && r.Request.URL != nil {
+		return r.Request.URL.Parse(lv)
+	}
+	return url.Parse(lv)
+}
+
+// ReadResponse reads and returns an HTTP response from r.
+// The req parameter optionally specifies the Request that corresponds
+// to this Response. If nil, a GET request is assumed.
+// Clients must call resp.Body.Close when finished reading resp.Body.
+// After that call, clients can inspect resp.Trailer to find key/value
+// pairs included in the response trailer.
+func ReadResponse(r *bufio.Reader, req *Request) (*Response, error) {
+	tp := textproto.NewReader(r)
+	resp := &Response{
+		Request: req,
+	}
+
+	// Parse the first line of the response.
+	line, err := tp.ReadLine()
+	if err != nil {
+		if err == io.EOF {
+			err = io.ErrUnexpectedEOF
+		}
+		return nil, err
+	}
+	proto, status, ok := strings.Cut(line, " ")
+	if !ok {
+		return nil, badStringError("malformed HTTP response", line)
+	}
+	resp.Proto = proto
+	resp.Status = strings.TrimLeft(status, " ")
+
+	statusCode, _, _ := strings.Cut(resp.Status, " ")
+	if len(statusCode) != 3 {
+		return nil, badStringError("malformed HTTP status code", statusCode)
+	}
+	resp.StatusCode, err = strconv.Atoi(statusCode)
+	if err != nil || resp.StatusCode < 0 {
+		return nil, badStringError("malformed HTTP status code", statusCode)
+	}
+	if resp.ProtoMajor, resp.ProtoMinor, ok = ParseHTTPVersion(resp.Proto); !ok {
+		return nil, badStringError("malformed HTTP version", resp.Proto)
+	}
+
+	// Parse the response headers.
+	mimeHeader, err := tp.ReadMIMEHeader()
+	if err != nil {
+		if err == io.EOF {
+			err = io.ErrUnexpectedEOF
+		}
+		return nil, err
+	}
+	resp.Header = Header(mimeHeader)
+
+	fixPragmaCacheControl(resp.Header)
+
+	err = readTransfer(resp, r)
+	if err != nil {
+		return nil, err
+	}
+
+	return resp, nil
+}
+
+// RFC 7234, section 5.4: Should treat
+//
+//	Pragma: no-cache
+//
+// like
+//
+//	Cache-Control: no-cache
+func fixPragmaCacheControl(header Header) {
+	if hp, ok := header["Pragma"]; ok && len(hp) > 0 && hp[0] == "no-cache" {
+		if _, presentcc := header["Cache-Control"]; !presentcc {
+			header["Cache-Control"] = []string{"no-cache"}
+		}
+	}
+}
+
+// ProtoAtLeast reports whether the HTTP protocol used
+// in the response is at least major.minor.
+func (r *Response) ProtoAtLeast(major, minor int) bool {
+	return r.ProtoMajor > major ||
+		r.ProtoMajor == major && r.ProtoMinor >= minor
+}
+
+// Write writes r to w in the HTTP/1.x server response format,
+// including the status line, headers, body, and optional trailer.
+//
+// This method consults the following fields of the response r:
+//
+//	StatusCode
+//	ProtoMajor
+//	ProtoMinor
+//	Request.Method
+//	TransferEncoding
+//	Trailer
+//	Body
+//	ContentLength
+//	Header, values for non-canonical keys will have unpredictable behavior
+//
+// The Response Body is closed after it is sent.
+func (r *Response) Write(w io.Writer) error {
+	// Status line
+	text := r.Status
+	if text == "" {
+		text = StatusText(r.StatusCode)
+		if text == "" {
+			text = "status code " + strconv.Itoa(r.StatusCode)
+		}
+	} else {
+		// Just to reduce stutter, if user set r.Status to "200 OK" and StatusCode to 200.
+		// Not important.
+		text = strings.TrimPrefix(text, strconv.Itoa(r.StatusCode)+" ")
+	}
+
+	if _, err := fmt.Fprintf(w, "HTTP/%d.%d %03d %s\r\n", r.ProtoMajor, r.ProtoMinor, r.StatusCode, text); err != nil {
+		return err
+	}
+
+	// Clone it, so we can modify r1 as needed.
+	r1 := new(Response)
+	*r1 = *r
+	if r1.ContentLength == 0 && r1.Body != nil {
+		// Is it actually 0 length? Or just unknown?
+		var buf [1]byte
+		n, err := r1.Body.Read(buf[:])
+		if err != nil && err != io.EOF {
+			return err
+		}
+		if n == 0 {
+			// Reset it to a known zero reader, in case underlying one
+			// is unhappy being read repeatedly.
+			r1.Body = NoBody
+		} else {
+			r1.ContentLength = -1
+			r1.Body = struct {
+				io.Reader
+				io.Closer
+			}{
+				io.MultiReader(bytes.NewReader(buf[:1]), r.Body),
+				r.Body,
+			}
+		}
+	}
+	// If we're sending a non-chunked HTTP/1.1 response without a
+	// content-length, the only way to do that is the old HTTP/1.0
+	// way, by noting the EOF with a connection close, so we need
+	// to set Close.
+	if r1.ContentLength == -1 && !r1.Close && r1.ProtoAtLeast(1, 1) && !chunked(r1.TransferEncoding) && !r1.Uncompressed {
+		r1.Close = true
+	}
+
+	// Process Body,ContentLength,Close,Trailer
+	tw, err := newTransferWriter(r1)
+	if err != nil {
+		return err
+	}
+	err = tw.writeHeader(w, nil)
+	if err != nil {
+		return err
+	}
+
+	// Rest of header
+	err = r.Header.WriteSubset(w, respExcludeHeader)
+	if err != nil {
+		return err
+	}
+
+	// contentLengthAlreadySent may have been already sent for
+	// POST/PUT requests, even if zero length. See Issue 8180.
+	contentLengthAlreadySent := tw.shouldSendContentLength()
+	if r1.ContentLength == 0 && !chunked(r1.TransferEncoding) && !contentLengthAlreadySent && bodyAllowedForStatus(r.StatusCode) {
+		if _, err := io.WriteString(w, "Content-Length: 0\r\n"); err != nil {
+			return err
+		}
+	}
+
+	// End-of-header
+	if _, err := io.WriteString(w, "\r\n"); err != nil {
+		return err
+	}
+
+	// Write body and trailer
+	err = tw.writeBody(w)
+	if err != nil {
+		return err
+	}
+
+	// Success
+	return nil
+}
+
+func (r *Response) closeBody() {
+	if r.Body != nil {
+		r.Body.Close()
+	}
+}
+
+// bodyIsWritable reports whether the Body supports writing. The
+// Transport returns Writable bodies for 101 Switching Protocols
+// responses.
+// The Transport uses this method to determine whether a persistent
+// connection is done being managed from its perspective. Once we
+// return a writable response body to a user, the net/http package is
+// done managing that connection.
+func (r *Response) bodyIsWritable() bool {
+	_, ok := r.Body.(io.Writer)
+	return ok
+}
+
+// isProtocolSwitch reports whether the response code and header
+// indicate a successful protocol upgrade response.
+func (r *Response) isProtocolSwitch() bool {
+	return isProtocolSwitchResponse(r.StatusCode, r.Header)
+}
+
+// isProtocolSwitchResponse reports whether the response code and
+// response header indicate a successful protocol upgrade response.
+func isProtocolSwitchResponse(code int, h Header) bool {
+	return code == StatusSwitchingProtocols && isProtocolSwitchHeader(h)
+}
+
+// isProtocolSwitchHeader reports whether the request or response header
+// is for a protocol switch.
+func isProtocolSwitchHeader(h Header) bool {
+	return h.Get("Upgrade") != "" &&
+		httpguts.HeaderValuesContainsToken(h["Connection"], "Upgrade")
+}
diff --git a/contrib/go/_std_1.18/src/net/http/roundtrip.go b/contrib/go/_std_1.19/src/net/http/roundtrip.go
index c4c5d3b6eb..c4c5d3b6eb 100644
--- a/contrib/go/_std_1.18/src/net/http/roundtrip.go
+++ b/contrib/go/_std_1.19/src/net/http/roundtrip.go
diff --git a/contrib/go/_std_1.19/src/net/http/server.go b/contrib/go/_std_1.19/src/net/http/server.go
new file mode 100644
index 0000000000..87dd412984
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/http/server.go
@@ -0,0 +1,3655 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// HTTP server. See RFC 7230 through 7235.
+
+package http
+
+import (
+	"bufio"
+	"bytes"
+	"context"
+	"crypto/tls"
+	"errors"
+	"fmt"
+	"internal/godebug"
+	"io"
+	"log"
+	"math/rand"
+	"net"
+	"net/textproto"
+	"net/url"
+	urlpkg "net/url"
+	"path"
+	"runtime"
+	"sort"
+	"strconv"
+	"strings"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"golang.org/x/net/http/httpguts"
+)
+
+// Errors used by the HTTP server.
+var (
+	// ErrBodyNotAllowed is returned by ResponseWriter.Write calls
+	// when the HTTP method or response code does not permit a
+	// body.
+	ErrBodyNotAllowed = errors.New("http: request method or response status code does not allow body")
+
+	// ErrHijacked is returned by ResponseWriter.Write calls when
+	// the underlying connection has been hijacked using the
+	// Hijacker interface. A zero-byte write on a hijacked
+	// connection will return ErrHijacked without any other side
+	// effects.
+	ErrHijacked = errors.New("http: connection has been hijacked")
+
+	// ErrContentLength is returned by ResponseWriter.Write calls
+	// when a Handler set a Content-Length response header with a
+	// declared size and then attempted to write more bytes than
+	// declared.
+	ErrContentLength = errors.New("http: wrote more than the declared Content-Length")
+
+	// Deprecated: ErrWriteAfterFlush is no longer returned by
+	// anything in the net/http package. Callers should not
+	// compare errors against this variable.
+	ErrWriteAfterFlush = errors.New("unused")
+)
+
+// A Handler responds to an HTTP request.
+//
+// ServeHTTP should write reply headers and data to the ResponseWriter
+// and then return. Returning signals that the request is finished; it
+// is not valid to use the ResponseWriter or read from the
+// Request.Body after or concurrently with the completion of the
+// ServeHTTP call.
+//
+// Depending on the HTTP client software, HTTP protocol version, and
+// any intermediaries between the client and the Go server, it may not
+// be possible to read from the Request.Body after writing to the
+// ResponseWriter. Cautious handlers should read the Request.Body
+// first, and then reply.
+//
+// Except for reading the body, handlers should not modify the
+// provided Request.
+//
+// If ServeHTTP panics, the server (the caller of ServeHTTP) assumes
+// that the effect of the panic was isolated to the active request.
+// It recovers the panic, logs a stack trace to the server error log,
+// and either closes the network connection or sends an HTTP/2
+// RST_STREAM, depending on the HTTP protocol. To abort a handler so
+// the client sees an interrupted response but the server doesn't log
+// an error, panic with the value ErrAbortHandler.
+type Handler interface {
+	ServeHTTP(ResponseWriter, *Request)
+}
+
+// A ResponseWriter interface is used by an HTTP handler to
+// construct an HTTP response.
+//
+// A ResponseWriter may not be used after the Handler.ServeHTTP method
+// has returned.
+type ResponseWriter interface {
+	// Header returns the header map that will be sent by
+	// WriteHeader. The Header map also is the mechanism with which
+	// Handlers can set HTTP trailers.
+	//
+	// Changing the header map after a call to WriteHeader (or
+	// Write) has no effect unless the HTTP status code was of the
+	// 1xx class or the modified headers are trailers.
+	//
+	// There are two ways to set Trailers. The preferred way is to
+	// predeclare in the headers which trailers you will later
+	// send by setting the "Trailer" header to the names of the
+	// trailer keys which will come later. In this case, those
+	// keys of the Header map are treated as if they were
+	// trailers. See the example. The second way, for trailer
+	// keys not known to the Handler until after the first Write,
+	// is to prefix the Header map keys with the TrailerPrefix
+	// constant value. See TrailerPrefix.
+	//
+	// To suppress automatic response headers (such as "Date"), set
+	// their value to nil.
+	Header() Header
+
+	// Write writes the data to the connection as part of an HTTP reply.
+	//
+	// If WriteHeader has not yet been called, Write calls
+	// WriteHeader(http.StatusOK) before writing the data. If the Header
+	// does not contain a Content-Type line, Write adds a Content-Type set
+	// to the result of passing the initial 512 bytes of written data to
+	// DetectContentType. Additionally, if the total size of all written
+	// data is under a few KB and there are no Flush calls, the
+	// Content-Length header is added automatically.
+	//
+	// Depending on the HTTP protocol version and the client, calling
+	// Write or WriteHeader may prevent future reads on the
+	// Request.Body. For HTTP/1.x requests, handlers should read any
+	// needed request body data before writing the response. Once the
+	// headers have been flushed (due to either an explicit Flusher.Flush
+	// call or writing enough data to trigger a flush), the request body
+	// may be unavailable. For HTTP/2 requests, the Go HTTP server permits
+	// handlers to continue to read the request body while concurrently
+	// writing the response. However, such behavior may not be supported
+	// by all HTTP/2 clients. Handlers should read before writing if
+	// possible to maximize compatibility.
+	Write([]byte) (int, error)
+
+	// WriteHeader sends an HTTP response header with the provided
+	// status code.
+	//
+	// If WriteHeader is not called explicitly, the first call to Write
+	// will trigger an implicit WriteHeader(http.StatusOK).
+	// Thus explicit calls to WriteHeader are mainly used to
+	// send error codes or 1xx informational responses.
+	//
+	// The provided code must be a valid HTTP 1xx-5xx status code.
+	// Any number of 1xx headers may be written, followed by at most
+	// one 2xx-5xx header. 1xx headers are sent immediately, but 2xx-5xx
+	// headers may be buffered. Use the Flusher interface to send
+	// buffered data. The header map is cleared when 2xx-5xx headers are
+	// sent, but not with 1xx headers.
+	//
+	// The server will automatically send a 100 (Continue) header
+	// on the first read from the request body if the request has
+	// an "Expect: 100-continue" header.
+	WriteHeader(statusCode int)
+}
+
+// The Flusher interface is implemented by ResponseWriters that allow
+// an HTTP handler to flush buffered data to the client.
+//
+// The default HTTP/1.x and HTTP/2 ResponseWriter implementations
+// support Flusher, but ResponseWriter wrappers may not. Handlers
+// should always test for this ability at runtime.
+//
+// Note that even for ResponseWriters that support Flush,
+// if the client is connected through an HTTP proxy,
+// the buffered data may not reach the client until the response
+// completes.
+type Flusher interface {
+	// Flush sends any buffered data to the client.
+	Flush()
+}
+
+// The Hijacker interface is implemented by ResponseWriters that allow
+// an HTTP handler to take over the connection.
+//
+// The default ResponseWriter for HTTP/1.x connections supports
+// Hijacker, but HTTP/2 connections intentionally do not.
+// ResponseWriter wrappers may also not support Hijacker. Handlers
+// should always test for this ability at runtime.
+type Hijacker interface {
+	// Hijack lets the caller take over the connection.
+	// After a call to Hijack the HTTP server library
+	// will not do anything else with the connection.
+	//
+	// It becomes the caller's responsibility to manage
+	// and close the connection.
+	//
+	// The returned net.Conn may have read or write deadlines
+	// already set, depending on the configuration of the
+	// Server. It is the caller's responsibility to set
+	// or clear those deadlines as needed.
+	//
+	// The returned bufio.Reader may contain unprocessed buffered
+	// data from the client.
+	//
+	// After a call to Hijack, the original Request.Body must not
+	// be used. The original Request's Context remains valid and
+	// is not canceled until the Request's ServeHTTP method
+	// returns.
+	Hijack() (net.Conn, *bufio.ReadWriter, error)
+}
+
+// The CloseNotifier interface is implemented by ResponseWriters which
+// allow detecting when the underlying connection has gone away.
+//
+// This mechanism can be used to cancel long operations on the server
+// if the client has disconnected before the response is ready.
+//
+// Deprecated: the CloseNotifier interface predates Go's context package.
+// New code should use Request.Context instead.
+type CloseNotifier interface {
+	// CloseNotify returns a channel that receives at most a
+	// single value (true) when the client connection has gone
+	// away.
+	//
+	// CloseNotify may wait to notify until Request.Body has been
+	// fully read.
+	//
+	// After the Handler has returned, there is no guarantee
+	// that the channel receives a value.
+	//
+	// If the protocol is HTTP/1.1 and CloseNotify is called while
+	// processing an idempotent request (such a GET) while
+	// HTTP/1.1 pipelining is in use, the arrival of a subsequent
+	// pipelined request may cause a value to be sent on the
+	// returned channel. In practice HTTP/1.1 pipelining is not
+	// enabled in browsers and not seen often in the wild. If this
+	// is a problem, use HTTP/2 or only use CloseNotify on methods
+	// such as POST.
+	CloseNotify() <-chan bool
+}
+
+var (
+	// ServerContextKey is a context key. It can be used in HTTP
+	// handlers with Context.Value to access the server that
+	// started the handler. The associated value will be of
+	// type *Server.
+	ServerContextKey = &contextKey{"http-server"}
+
+	// LocalAddrContextKey is a context key. It can be used in
+	// HTTP handlers with Context.Value to access the local
+	// address the connection arrived on.
+	// The associated value will be of type net.Addr.
+	LocalAddrContextKey = &contextKey{"local-addr"}
+)
+
+// A conn represents the server side of an HTTP connection.
+type conn struct {
+	// server is the server on which the connection arrived.
+	// Immutable; never nil.
+	server *Server
+
+	// cancelCtx cancels the connection-level context.
+	cancelCtx context.CancelFunc
+
+	// rwc is the underlying network connection.
+	// This is never wrapped by other types and is the value given out
+	// to CloseNotifier callers. It is usually of type *net.TCPConn or
+	// *tls.Conn.
+	rwc net.Conn
+
+	// remoteAddr is rwc.RemoteAddr().String(). It is not populated synchronously
+	// inside the Listener's Accept goroutine, as some implementations block.
+	// It is populated immediately inside the (*conn).serve goroutine.
+	// This is the value of a Handler's (*Request).RemoteAddr.
+	remoteAddr string
+
+	// tlsState is the TLS connection state when using TLS.
+	// nil means not TLS.
+	tlsState *tls.ConnectionState
+
+	// werr is set to the first write error to rwc.
+	// It is set via checkConnErrorWriter{w}, where bufw writes.
+	werr error
+
+	// r is bufr's read source. It's a wrapper around rwc that provides
+	// io.LimitedReader-style limiting (while reading request headers)
+	// and functionality to support CloseNotifier. See *connReader docs.
+	r *connReader
+
+	// bufr reads from r.
+	bufr *bufio.Reader
+
+	// bufw writes to checkConnErrorWriter{c}, which populates werr on error.
+	bufw *bufio.Writer
+
+	// lastMethod is the method of the most recent request
+	// on this connection, if any.
+	lastMethod string
+
+	curReq atomic.Value // of *response (which has a Request in it)
+
+	curState struct{ atomic uint64 } // packed (unixtime<<8|uint8(ConnState))
+
+	// mu guards hijackedv
+	mu sync.Mutex
+
+	// hijackedv is whether this connection has been hijacked
+	// by a Handler with the Hijacker interface.
+	// It is guarded by mu.
+	hijackedv bool
+}
+
+func (c *conn) hijacked() bool {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	return c.hijackedv
+}
+
+// c.mu must be held.
+func (c *conn) hijackLocked() (rwc net.Conn, buf *bufio.ReadWriter, err error) {
+	if c.hijackedv {
+		return nil, nil, ErrHijacked
+	}
+	c.r.abortPendingRead()
+
+	c.hijackedv = true
+	rwc = c.rwc
+	rwc.SetDeadline(time.Time{})
+
+	buf = bufio.NewReadWriter(c.bufr, bufio.NewWriter(rwc))
+	if c.r.hasByte {
+		if _, err := c.bufr.Peek(c.bufr.Buffered() + 1); err != nil {
+			return nil, nil, fmt.Errorf("unexpected Peek failure reading buffered byte: %v", err)
+		}
+	}
+	c.setState(rwc, StateHijacked, runHooks)
+	return
+}
+
+// This should be >= 512 bytes for DetectContentType,
+// but otherwise it's somewhat arbitrary.
+const bufferBeforeChunkingSize = 2048
+
+// chunkWriter writes to a response's conn buffer, and is the writer
+// wrapped by the response.w buffered writer.
+//
+// chunkWriter also is responsible for finalizing the Header, including
+// conditionally setting the Content-Type and setting a Content-Length
+// in cases where the handler's final output is smaller than the buffer
+// size. It also conditionally adds chunk headers, when in chunking mode.
+//
+// See the comment above (*response).Write for the entire write flow.
+type chunkWriter struct {
+	res *response
+
+	// header is either nil or a deep clone of res.handlerHeader
+	// at the time of res.writeHeader, if res.writeHeader is
+	// called and extra buffering is being done to calculate
+	// Content-Type and/or Content-Length.
+	header Header
+
+	// wroteHeader tells whether the header's been written to "the
+	// wire" (or rather: w.conn.buf). this is unlike
+	// (*response).wroteHeader, which tells only whether it was
+	// logically written.
+	wroteHeader bool
+
+	// set by the writeHeader method:
+	chunking bool // using chunked transfer encoding for reply body
+}
+
+var (
+	crlf       = []byte("\r\n")
+	colonSpace = []byte(": ")
+)
+
+func (cw *chunkWriter) Write(p []byte) (n int, err error) {
+	if !cw.wroteHeader {
+		cw.writeHeader(p)
+	}
+	if cw.res.req.Method == "HEAD" {
+		// Eat writes.
+		return len(p), nil
+	}
+	if cw.chunking {
+		_, err = fmt.Fprintf(cw.res.conn.bufw, "%x\r\n", len(p))
+		if err != nil {
+			cw.res.conn.rwc.Close()
+			return
+		}
+	}
+	n, err = cw.res.conn.bufw.Write(p)
+	if cw.chunking && err == nil {
+		_, err = cw.res.conn.bufw.Write(crlf)
+	}
+	if err != nil {
+		cw.res.conn.rwc.Close()
+	}
+	return
+}
+
+func (cw *chunkWriter) flush() {
+	if !cw.wroteHeader {
+		cw.writeHeader(nil)
+	}
+	cw.res.conn.bufw.Flush()
+}
+
+func (cw *chunkWriter) close() {
+	if !cw.wroteHeader {
+		cw.writeHeader(nil)
+	}
+	if cw.chunking {
+		bw := cw.res.conn.bufw // conn's bufio writer
+		// zero chunk to mark EOF
+		bw.WriteString("0\r\n")
+		if trailers := cw.res.finalTrailers(); trailers != nil {
+			trailers.Write(bw) // the writer handles noting errors
+		}
+		// final blank line after the trailers (whether
+		// present or not)
+		bw.WriteString("\r\n")
+	}
+}
+
+// A response represents the server side of an HTTP response.
+type response struct {
+	conn             *conn
+	req              *Request // request for this response
+	reqBody          io.ReadCloser
+	cancelCtx        context.CancelFunc // when ServeHTTP exits
+	wroteHeader      bool               // a non-1xx header has been (logically) written
+	wroteContinue    bool               // 100 Continue response was written
+	wants10KeepAlive bool               // HTTP/1.0 w/ Connection "keep-alive"
+	wantsClose       bool               // HTTP request has Connection "close"
+
+	// canWriteContinue is a boolean value accessed as an atomic int32
+	// that says whether or not a 100 Continue header can be written
+	// to the connection.
+	// writeContinueMu must be held while writing the header.
+	// These two fields together synchronize the body reader
+	// (the expectContinueReader, which wants to write 100 Continue)
+	// against the main writer.
+	canWriteContinue atomicBool
+	writeContinueMu  sync.Mutex
+
+	w  *bufio.Writer // buffers output in chunks to chunkWriter
+	cw chunkWriter
+
+	// handlerHeader is the Header that Handlers get access to,
+	// which may be retained and mutated even after WriteHeader.
+	// handlerHeader is copied into cw.header at WriteHeader
+	// time, and privately mutated thereafter.
+	handlerHeader Header
+	calledHeader  bool // handler accessed handlerHeader via Header
+
+	written       int64 // number of bytes written in body
+	contentLength int64 // explicitly-declared Content-Length; or -1
+	status        int   // status code passed to WriteHeader
+
+	// close connection after this reply.  set on request and
+	// updated after response from handler if there's a
+	// "Connection: keep-alive" response header and a
+	// Content-Length.
+	closeAfterReply bool
+
+	// requestBodyLimitHit is set by requestTooLarge when
+	// maxBytesReader hits its max size. It is checked in
+	// WriteHeader, to make sure we don't consume the
+	// remaining request body to try to advance to the next HTTP
+	// request. Instead, when this is set, we stop reading
+	// subsequent requests on this connection and stop reading
+	// input from it.
+	requestBodyLimitHit bool
+
+	// trailers are the headers to be sent after the handler
+	// finishes writing the body. This field is initialized from
+	// the Trailer response header when the response header is
+	// written.
+	trailers []string
+
+	handlerDone atomicBool // set true when the handler exits
+
+	// Buffers for Date, Content-Length, and status code
+	dateBuf   [len(TimeFormat)]byte
+	clenBuf   [10]byte
+	statusBuf [3]byte
+
+	// closeNotifyCh is the channel returned by CloseNotify.
+	// TODO(bradfitz): this is currently (for Go 1.8) always
+	// non-nil. Make this lazily-created again as it used to be?
+	closeNotifyCh  chan bool
+	didCloseNotify int32 // atomic (only 0->1 winner should send)
+}
+
+// TrailerPrefix is a magic prefix for ResponseWriter.Header map keys
+// that, if present, signals that the map entry is actually for
+// the response trailers, and not the response headers. The prefix
+// is stripped after the ServeHTTP call finishes and the values are
+// sent in the trailers.
+//
+// This mechanism is intended only for trailers that are not known
+// prior to the headers being written. If the set of trailers is fixed
+// or known before the header is written, the normal Go trailers mechanism
+// is preferred:
+//
+//	https://pkg.go.dev/net/http#ResponseWriter
+//	https://pkg.go.dev/net/http#example-ResponseWriter-Trailers
+const TrailerPrefix = "Trailer:"
+
+// finalTrailers is called after the Handler exits and returns a non-nil
+// value if the Handler set any trailers.
+func (w *response) finalTrailers() Header {
+	var t Header
+	for k, vv := range w.handlerHeader {
+		if strings.HasPrefix(k, TrailerPrefix) {
+			if t == nil {
+				t = make(Header)
+			}
+			t[strings.TrimPrefix(k, TrailerPrefix)] = vv
+		}
+	}
+	for _, k := range w.trailers {
+		if t == nil {
+			t = make(Header)
+		}
+		for _, v := range w.handlerHeader[k] {
+			t.Add(k, v)
+		}
+	}
+	return t
+}
+
+type atomicBool int32
+
+func (b *atomicBool) isSet() bool { return atomic.LoadInt32((*int32)(b)) != 0 }
+func (b *atomicBool) setTrue()    { atomic.StoreInt32((*int32)(b), 1) }
+func (b *atomicBool) setFalse()   { atomic.StoreInt32((*int32)(b), 0) }
+
+// declareTrailer is called for each Trailer header when the
+// response header is written. It notes that a header will need to be
+// written in the trailers at the end of the response.
+func (w *response) declareTrailer(k string) {
+	k = CanonicalHeaderKey(k)
+	if !httpguts.ValidTrailerHeader(k) {
+		// Forbidden by RFC 7230, section 4.1.2
+		return
+	}
+	w.trailers = append(w.trailers, k)
+}
+
+// requestTooLarge is called by maxBytesReader when too much input has
+// been read from the client.
+func (w *response) requestTooLarge() {
+	w.closeAfterReply = true
+	w.requestBodyLimitHit = true
+	if !w.wroteHeader {
+		w.Header().Set("Connection", "close")
+	}
+}
+
+// needsSniff reports whether a Content-Type still needs to be sniffed.
+func (w *response) needsSniff() bool {
+	_, haveType := w.handlerHeader["Content-Type"]
+	return !w.cw.wroteHeader && !haveType && w.written < sniffLen
+}
+
+// writerOnly hides an io.Writer value's optional ReadFrom method
+// from io.Copy.
+type writerOnly struct {
+	io.Writer
+}
+
+// ReadFrom is here to optimize copying from an *os.File regular file
+// to a *net.TCPConn with sendfile, or from a supported src type such
+// as a *net.TCPConn on Linux with splice.
+func (w *response) ReadFrom(src io.Reader) (n int64, err error) {
+	bufp := copyBufPool.Get().(*[]byte)
+	buf := *bufp
+	defer copyBufPool.Put(bufp)
+
+	// Our underlying w.conn.rwc is usually a *TCPConn (with its
+	// own ReadFrom method). If not, just fall back to the normal
+	// copy method.
+	rf, ok := w.conn.rwc.(io.ReaderFrom)
+	if !ok {
+		return io.CopyBuffer(writerOnly{w}, src, buf)
+	}
+
+	// Copy the first sniffLen bytes before switching to ReadFrom.
+	// This ensures we don't start writing the response before the
+	// source is available (see golang.org/issue/5660) and provides
+	// enough bytes to perform Content-Type sniffing when required.
+	if !w.cw.wroteHeader {
+		n0, err := io.CopyBuffer(writerOnly{w}, io.LimitReader(src, sniffLen), buf)
+		n += n0
+		if err != nil || n0 < sniffLen {
+			return n, err
+		}
+	}
+
+	w.w.Flush()  // get rid of any previous writes
+	w.cw.flush() // make sure Header is written; flush data to rwc
+
+	// Now that cw has been flushed, its chunking field is guaranteed initialized.
+	if !w.cw.chunking && w.bodyAllowed() {
+		n0, err := rf.ReadFrom(src)
+		n += n0
+		w.written += n0
+		return n, err
+	}
+
+	n0, err := io.CopyBuffer(writerOnly{w}, src, buf)
+	n += n0
+	return n, err
+}
+
+// debugServerConnections controls whether all server connections are wrapped
+// with a verbose logging wrapper.
+const debugServerConnections = false
+
+// Create new connection from rwc.
+func (srv *Server) newConn(rwc net.Conn) *conn {
+	c := &conn{
+		server: srv,
+		rwc:    rwc,
+	}
+	if debugServerConnections {
+		c.rwc = newLoggingConn("server", c.rwc)
+	}
+	return c
+}
+
+type readResult struct {
+	_   incomparable
+	n   int
+	err error
+	b   byte // byte read, if n == 1
+}
+
+// connReader is the io.Reader wrapper used by *conn. It combines a
+// selectively-activated io.LimitedReader (to bound request header
+// read sizes) with support for selectively keeping an io.Reader.Read
+// call blocked in a background goroutine to wait for activity and
+// trigger a CloseNotifier channel.
+type connReader struct {
+	conn *conn
+
+	mu      sync.Mutex // guards following
+	hasByte bool
+	byteBuf [1]byte
+	cond    *sync.Cond
+	inRead  bool
+	aborted bool  // set true before conn.rwc deadline is set to past
+	remain  int64 // bytes remaining
+}
+
+func (cr *connReader) lock() {
+	cr.mu.Lock()
+	if cr.cond == nil {
+		cr.cond = sync.NewCond(&cr.mu)
+	}
+}
+
+func (cr *connReader) unlock() { cr.mu.Unlock() }
+
+func (cr *connReader) startBackgroundRead() {
+	cr.lock()
+	defer cr.unlock()
+	if cr.inRead {
+		panic("invalid concurrent Body.Read call")
+	}
+	if cr.hasByte {
+		return
+	}
+	cr.inRead = true
+	cr.conn.rwc.SetReadDeadline(time.Time{})
+	go cr.backgroundRead()
+}
+
+func (cr *connReader) backgroundRead() {
+	n, err := cr.conn.rwc.Read(cr.byteBuf[:])
+	cr.lock()
+	if n == 1 {
+		cr.hasByte = true
+		// We were past the end of the previous request's body already
+		// (since we wouldn't be in a background read otherwise), so
+		// this is a pipelined HTTP request. Prior to Go 1.11 we used to
+		// send on the CloseNotify channel and cancel the context here,
+		// but the behavior was documented as only "may", and we only
+		// did that because that's how CloseNotify accidentally behaved
+		// in very early Go releases prior to context support. Once we
+		// added context support, people used a Handler's
+		// Request.Context() and passed it along. Having that context
+		// cancel on pipelined HTTP requests caused problems.
+		// Fortunately, almost nothing uses HTTP/1.x pipelining.
+		// Unfortunately, apt-get does, or sometimes does.
+		// New Go 1.11 behavior: don't fire CloseNotify or cancel
+		// contexts on pipelined requests. Shouldn't affect people, but
+		// fixes cases like Issue 23921. This does mean that a client
+		// closing their TCP connection after sending a pipelined
+		// request won't cancel the context, but we'll catch that on any
+		// write failure (in checkConnErrorWriter.Write).
+		// If the server never writes, yes, there are still contrived
+		// server & client behaviors where this fails to ever cancel the
+		// context, but that's kinda why HTTP/1.x pipelining died
+		// anyway.
+	}
+	if ne, ok := err.(net.Error); ok && cr.aborted && ne.Timeout() {
+		// Ignore this error. It's the expected error from
+		// another goroutine calling abortPendingRead.
+	} else if err != nil {
+		cr.handleReadError(err)
+	}
+	cr.aborted = false
+	cr.inRead = false
+	cr.unlock()
+	cr.cond.Broadcast()
+}
+
+func (cr *connReader) abortPendingRead() {
+	cr.lock()
+	defer cr.unlock()
+	if !cr.inRead {
+		return
+	}
+	cr.aborted = true
+	cr.conn.rwc.SetReadDeadline(aLongTimeAgo)
+	for cr.inRead {
+		cr.cond.Wait()
+	}
+	cr.conn.rwc.SetReadDeadline(time.Time{})
+}
+
+func (cr *connReader) setReadLimit(remain int64) { cr.remain = remain }
+func (cr *connReader) setInfiniteReadLimit()     { cr.remain = maxInt64 }
+func (cr *connReader) hitReadLimit() bool        { return cr.remain <= 0 }
+
+// handleReadError is called whenever a Read from the client returns a
+// non-nil error.
+//
+// The provided non-nil err is almost always io.EOF or a "use of
+// closed network connection". In any case, the error is not
+// particularly interesting, except perhaps for debugging during
+// development. Any error means the connection is dead and we should
+// down its context.
+//
+// It may be called from multiple goroutines.
+func (cr *connReader) handleReadError(_ error) {
+	cr.conn.cancelCtx()
+	cr.closeNotify()
+}
+
+// may be called from multiple goroutines.
+func (cr *connReader) closeNotify() {
+	res, _ := cr.conn.curReq.Load().(*response)
+	if res != nil && atomic.CompareAndSwapInt32(&res.didCloseNotify, 0, 1) {
+		res.closeNotifyCh <- true
+	}
+}
+
+func (cr *connReader) Read(p []byte) (n int, err error) {
+	cr.lock()
+	if cr.inRead {
+		cr.unlock()
+		if cr.conn.hijacked() {
+			panic("invalid Body.Read call. After hijacked, the original Request must not be used")
+		}
+		panic("invalid concurrent Body.Read call")
+	}
+	if cr.hitReadLimit() {
+		cr.unlock()
+		return 0, io.EOF
+	}
+	if len(p) == 0 {
+		cr.unlock()
+		return 0, nil
+	}
+	if int64(len(p)) > cr.remain {
+		p = p[:cr.remain]
+	}
+	if cr.hasByte {
+		p[0] = cr.byteBuf[0]
+		cr.hasByte = false
+		cr.unlock()
+		return 1, nil
+	}
+	cr.inRead = true
+	cr.unlock()
+	n, err = cr.conn.rwc.Read(p)
+
+	cr.lock()
+	cr.inRead = false
+	if err != nil {
+		cr.handleReadError(err)
+	}
+	cr.remain -= int64(n)
+	cr.unlock()
+
+	cr.cond.Broadcast()
+	return n, err
+}
+
+var (
+	bufioReaderPool   sync.Pool
+	bufioWriter2kPool sync.Pool
+	bufioWriter4kPool sync.Pool
+)
+
+var copyBufPool = sync.Pool{
+	New: func() any {
+		b := make([]byte, 32*1024)
+		return &b
+	},
+}
+
+func bufioWriterPool(size int) *sync.Pool {
+	switch size {
+	case 2 << 10:
+		return &bufioWriter2kPool
+	case 4 << 10:
+		return &bufioWriter4kPool
+	}
+	return nil
+}
+
+func newBufioReader(r io.Reader) *bufio.Reader {
+	if v := bufioReaderPool.Get(); v != nil {
+		br := v.(*bufio.Reader)
+		br.Reset(r)
+		return br
+	}
+	// Note: if this reader size is ever changed, update
+	// TestHandlerBodyClose's assumptions.
+	return bufio.NewReader(r)
+}
+
+func putBufioReader(br *bufio.Reader) {
+	br.Reset(nil)
+	bufioReaderPool.Put(br)
+}
+
+func newBufioWriterSize(w io.Writer, size int) *bufio.Writer {
+	pool := bufioWriterPool(size)
+	if pool != nil {
+		if v := pool.Get(); v != nil {
+			bw := v.(*bufio.Writer)
+			bw.Reset(w)
+			return bw
+		}
+	}
+	return bufio.NewWriterSize(w, size)
+}
+
+func putBufioWriter(bw *bufio.Writer) {
+	bw.Reset(nil)
+	if pool := bufioWriterPool(bw.Available()); pool != nil {
+		pool.Put(bw)
+	}
+}
+
+// DefaultMaxHeaderBytes is the maximum permitted size of the headers
+// in an HTTP request.
+// This can be overridden by setting Server.MaxHeaderBytes.
+const DefaultMaxHeaderBytes = 1 << 20 // 1 MB
+
+func (srv *Server) maxHeaderBytes() int {
+	if srv.MaxHeaderBytes > 0 {
+		return srv.MaxHeaderBytes
+	}
+	return DefaultMaxHeaderBytes
+}
+
+func (srv *Server) initialReadLimitSize() int64 {
+	return int64(srv.maxHeaderBytes()) + 4096 // bufio slop
+}
+
+// tlsHandshakeTimeout returns the time limit permitted for the TLS
+// handshake, or zero for unlimited.
+//
+// It returns the minimum of any positive ReadHeaderTimeout,
+// ReadTimeout, or WriteTimeout.
+func (srv *Server) tlsHandshakeTimeout() time.Duration {
+	var ret time.Duration
+	for _, v := range [...]time.Duration{
+		srv.ReadHeaderTimeout,
+		srv.ReadTimeout,
+		srv.WriteTimeout,
+	} {
+		if v <= 0 {
+			continue
+		}
+		if ret == 0 || v < ret {
+			ret = v
+		}
+	}
+	return ret
+}
+
+// wrapper around io.ReadCloser which on first read, sends an
+// HTTP/1.1 100 Continue header
+type expectContinueReader struct {
+	resp       *response
+	readCloser io.ReadCloser
+	closed     atomicBool
+	sawEOF     atomicBool
+}
+
+func (ecr *expectContinueReader) Read(p []byte) (n int, err error) {
+	if ecr.closed.isSet() {
+		return 0, ErrBodyReadAfterClose
+	}
+	w := ecr.resp
+	if !w.wroteContinue && w.canWriteContinue.isSet() && !w.conn.hijacked() {
+		w.wroteContinue = true
+		w.writeContinueMu.Lock()
+		if w.canWriteContinue.isSet() {
+			w.conn.bufw.WriteString("HTTP/1.1 100 Continue\r\n\r\n")
+			w.conn.bufw.Flush()
+			w.canWriteContinue.setFalse()
+		}
+		w.writeContinueMu.Unlock()
+	}
+	n, err = ecr.readCloser.Read(p)
+	if err == io.EOF {
+		ecr.sawEOF.setTrue()
+	}
+	return
+}
+
+func (ecr *expectContinueReader) Close() error {
+	ecr.closed.setTrue()
+	return ecr.readCloser.Close()
+}
+
+// TimeFormat is the time format to use when generating times in HTTP
+// headers. It is like time.RFC1123 but hard-codes GMT as the time
+// zone. The time being formatted must be in UTC for Format to
+// generate the correct format.
+//
+// For parsing this time format, see ParseTime.
+const TimeFormat = "Mon, 02 Jan 2006 15:04:05 GMT"
+
+// appendTime is a non-allocating version of []byte(t.UTC().Format(TimeFormat))
+func appendTime(b []byte, t time.Time) []byte {
+	const days = "SunMonTueWedThuFriSat"
+	const months = "JanFebMarAprMayJunJulAugSepOctNovDec"
+
+	t = t.UTC()
+	yy, mm, dd := t.Date()
+	hh, mn, ss := t.Clock()
+	day := days[3*t.Weekday():]
+	mon := months[3*(mm-1):]
+
+	return append(b,
+		day[0], day[1], day[2], ',', ' ',
+		byte('0'+dd/10), byte('0'+dd%10), ' ',
+		mon[0], mon[1], mon[2], ' ',
+		byte('0'+yy/1000), byte('0'+(yy/100)%10), byte('0'+(yy/10)%10), byte('0'+yy%10), ' ',
+		byte('0'+hh/10), byte('0'+hh%10), ':',
+		byte('0'+mn/10), byte('0'+mn%10), ':',
+		byte('0'+ss/10), byte('0'+ss%10), ' ',
+		'G', 'M', 'T')
+}
+
+var errTooLarge = errors.New("http: request too large")
+
+// Read next request from connection.
+func (c *conn) readRequest(ctx context.Context) (w *response, err error) {
+	if c.hijacked() {
+		return nil, ErrHijacked
+	}
+
+	var (
+		wholeReqDeadline time.Time // or zero if none
+		hdrDeadline      time.Time // or zero if none
+	)
+	t0 := time.Now()
+	if d := c.server.readHeaderTimeout(); d > 0 {
+		hdrDeadline = t0.Add(d)
+	}
+	if d := c.server.ReadTimeout; d > 0 {
+		wholeReqDeadline = t0.Add(d)
+	}
+	c.rwc.SetReadDeadline(hdrDeadline)
+	if d := c.server.WriteTimeout; d > 0 {
+		defer func() {
+			c.rwc.SetWriteDeadline(time.Now().Add(d))
+		}()
+	}
+
+	c.r.setReadLimit(c.server.initialReadLimitSize())
+	if c.lastMethod == "POST" {
+		// RFC 7230 section 3 tolerance for old buggy clients.
+		peek, _ := c.bufr.Peek(4) // ReadRequest will get err below
+		c.bufr.Discard(numLeadingCRorLF(peek))
+	}
+	req, err := readRequest(c.bufr)
+	if err != nil {
+		if c.r.hitReadLimit() {
+			return nil, errTooLarge
+		}
+		return nil, err
+	}
+
+	if !http1ServerSupportsRequest(req) {
+		return nil, statusError{StatusHTTPVersionNotSupported, "unsupported protocol version"}
+	}
+
+	c.lastMethod = req.Method
+	c.r.setInfiniteReadLimit()
+
+	hosts, haveHost := req.Header["Host"]
+	isH2Upgrade := req.isH2Upgrade()
+	if req.ProtoAtLeast(1, 1) && (!haveHost || len(hosts) == 0) && !isH2Upgrade && req.Method != "CONNECT" {
+		return nil, badRequestError("missing required Host header")
+	}
+	if len(hosts) == 1 && !httpguts.ValidHostHeader(hosts[0]) {
+		return nil, badRequestError("malformed Host header")
+	}
+	for k, vv := range req.Header {
+		if !httpguts.ValidHeaderFieldName(k) {
+			return nil, badRequestError("invalid header name")
+		}
+		for _, v := range vv {
+			if !httpguts.ValidHeaderFieldValue(v) {
+				return nil, badRequestError("invalid header value")
+			}
+		}
+	}
+	delete(req.Header, "Host")
+
+	ctx, cancelCtx := context.WithCancel(ctx)
+	req.ctx = ctx
+	req.RemoteAddr = c.remoteAddr
+	req.TLS = c.tlsState
+	if body, ok := req.Body.(*body); ok {
+		body.doEarlyClose = true
+	}
+
+	// Adjust the read deadline if necessary.
+	if !hdrDeadline.Equal(wholeReqDeadline) {
+		c.rwc.SetReadDeadline(wholeReqDeadline)
+	}
+
+	w = &response{
+		conn:          c,
+		cancelCtx:     cancelCtx,
+		req:           req,
+		reqBody:       req.Body,
+		handlerHeader: make(Header),
+		contentLength: -1,
+		closeNotifyCh: make(chan bool, 1),
+
+		// We populate these ahead of time so we're not
+		// reading from req.Header after their Handler starts
+		// and maybe mutates it (Issue 14940)
+		wants10KeepAlive: req.wantsHttp10KeepAlive(),
+		wantsClose:       req.wantsClose(),
+	}
+	if isH2Upgrade {
+		w.closeAfterReply = true
+	}
+	w.cw.res = w
+	w.w = newBufioWriterSize(&w.cw, bufferBeforeChunkingSize)
+	return w, nil
+}
+
+// http1ServerSupportsRequest reports whether Go's HTTP/1.x server
+// supports the given request.
+func http1ServerSupportsRequest(req *Request) bool {
+	if req.ProtoMajor == 1 {
+		return true
+	}
+	// Accept "PRI * HTTP/2.0" upgrade requests, so Handlers can
+	// wire up their own HTTP/2 upgrades.
+	if req.ProtoMajor == 2 && req.ProtoMinor == 0 &&
+		req.Method == "PRI" && req.RequestURI == "*" {
+		return true
+	}
+	// Reject HTTP/0.x, and all other HTTP/2+ requests (which
+	// aren't encoded in ASCII anyway).
+	return false
+}
+
+func (w *response) Header() Header {
+	if w.cw.header == nil && w.wroteHeader && !w.cw.wroteHeader {
+		// Accessing the header between logically writing it
+		// and physically writing it means we need to allocate
+		// a clone to snapshot the logically written state.
+		w.cw.header = w.handlerHeader.Clone()
+	}
+	w.calledHeader = true
+	return w.handlerHeader
+}
+
+// maxPostHandlerReadBytes is the max number of Request.Body bytes not
+// consumed by a handler that the server will read from the client
+// in order to keep a connection alive. If there are more bytes than
+// this then the server to be paranoid instead sends a "Connection:
+// close" response.
+//
+// This number is approximately what a typical machine's TCP buffer
+// size is anyway.  (if we have the bytes on the machine, we might as
+// well read them)
+const maxPostHandlerReadBytes = 256 << 10
+
+func checkWriteHeaderCode(code int) {
+	// Issue 22880: require valid WriteHeader status codes.
+	// For now we only enforce that it's three digits.
+	// In the future we might block things over 599 (600 and above aren't defined
+	// at https://httpwg.org/specs/rfc7231.html#status.codes).
+	// But for now any three digits.
+	//
+	// We used to send "HTTP/1.1 000 0" on the wire in responses but there's
+	// no equivalent bogus thing we can realistically send in HTTP/2,
+	// so we'll consistently panic instead and help people find their bugs
+	// early. (We can't return an error from WriteHeader even if we wanted to.)
+	if code < 100 || code > 999 {
+		panic(fmt.Sprintf("invalid WriteHeader code %v", code))
+	}
+}
+
+// relevantCaller searches the call stack for the first function outside of net/http.
+// The purpose of this function is to provide more helpful error messages.
+func relevantCaller() runtime.Frame {
+	pc := make([]uintptr, 16)
+	n := runtime.Callers(1, pc)
+	frames := runtime.CallersFrames(pc[:n])
+	var frame runtime.Frame
+	for {
+		frame, more := frames.Next()
+		if !strings.HasPrefix(frame.Function, "net/http.") {
+			return frame
+		}
+		if !more {
+			break
+		}
+	}
+	return frame
+}
+
+func (w *response) WriteHeader(code int) {
+	if w.conn.hijacked() {
+		caller := relevantCaller()
+		w.conn.server.logf("http: response.WriteHeader on hijacked connection from %s (%s:%d)", caller.Function, path.Base(caller.File), caller.Line)
+		return
+	}
+	if w.wroteHeader {
+		caller := relevantCaller()
+		w.conn.server.logf("http: superfluous response.WriteHeader call from %s (%s:%d)", caller.Function, path.Base(caller.File), caller.Line)
+		return
+	}
+	checkWriteHeaderCode(code)
+
+	// Handle informational headers
+	if code >= 100 && code <= 199 {
+		// Prevent a potential race with an automatically-sent 100 Continue triggered by Request.Body.Read()
+		if code == 100 && w.canWriteContinue.isSet() {
+			w.writeContinueMu.Lock()
+			w.canWriteContinue.setFalse()
+			w.writeContinueMu.Unlock()
+		}
+
+		writeStatusLine(w.conn.bufw, w.req.ProtoAtLeast(1, 1), code, w.statusBuf[:])
+
+		// Per RFC 8297 we must not clear the current header map
+		w.handlerHeader.WriteSubset(w.conn.bufw, excludedHeadersNoBody)
+		w.conn.bufw.Write(crlf)
+		w.conn.bufw.Flush()
+
+		return
+	}
+
+	w.wroteHeader = true
+	w.status = code
+
+	if w.calledHeader && w.cw.header == nil {
+		w.cw.header = w.handlerHeader.Clone()
+	}
+
+	if cl := w.handlerHeader.get("Content-Length"); cl != "" {
+		v, err := strconv.ParseInt(cl, 10, 64)
+		if err == nil && v >= 0 {
+			w.contentLength = v
+		} else {
+			w.conn.server.logf("http: invalid Content-Length of %q", cl)
+			w.handlerHeader.Del("Content-Length")
+		}
+	}
+}
+
+// extraHeader is the set of headers sometimes added by chunkWriter.writeHeader.
+// This type is used to avoid extra allocations from cloning and/or populating
+// the response Header map and all its 1-element slices.
+type extraHeader struct {
+	contentType      string
+	connection       string
+	transferEncoding string
+	date             []byte // written if not nil
+	contentLength    []byte // written if not nil
+}
+
+// Sorted the same as extraHeader.Write's loop.
+var extraHeaderKeys = [][]byte{
+	[]byte("Content-Type"),
+	[]byte("Connection"),
+	[]byte("Transfer-Encoding"),
+}
+
+var (
+	headerContentLength = []byte("Content-Length: ")
+	headerDate          = []byte("Date: ")
+)
+
+// Write writes the headers described in h to w.
+//
+// This method has a value receiver, despite the somewhat large size
+// of h, because it prevents an allocation. The escape analysis isn't
+// smart enough to realize this function doesn't mutate h.
+func (h extraHeader) Write(w *bufio.Writer) {
+	if h.date != nil {
+		w.Write(headerDate)
+		w.Write(h.date)
+		w.Write(crlf)
+	}
+	if h.contentLength != nil {
+		w.Write(headerContentLength)
+		w.Write(h.contentLength)
+		w.Write(crlf)
+	}
+	for i, v := range []string{h.contentType, h.connection, h.transferEncoding} {
+		if v != "" {
+			w.Write(extraHeaderKeys[i])
+			w.Write(colonSpace)
+			w.WriteString(v)
+			w.Write(crlf)
+		}
+	}
+}
+
+// writeHeader finalizes the header sent to the client and writes it
+// to cw.res.conn.bufw.
+//
+// p is not written by writeHeader, but is the first chunk of the body
+// that will be written. It is sniffed for a Content-Type if none is
+// set explicitly. It's also used to set the Content-Length, if the
+// total body size was small and the handler has already finished
+// running.
+func (cw *chunkWriter) writeHeader(p []byte) {
+	if cw.wroteHeader {
+		return
+	}
+	cw.wroteHeader = true
+
+	w := cw.res
+	keepAlivesEnabled := w.conn.server.doKeepAlives()
+	isHEAD := w.req.Method == "HEAD"
+
+	// header is written out to w.conn.buf below. Depending on the
+	// state of the handler, we either own the map or not. If we
+	// don't own it, the exclude map is created lazily for
+	// WriteSubset to remove headers. The setHeader struct holds
+	// headers we need to add.
+	header := cw.header
+	owned := header != nil
+	if !owned {
+		header = w.handlerHeader
+	}
+	var excludeHeader map[string]bool
+	delHeader := func(key string) {
+		if owned {
+			header.Del(key)
+			return
+		}
+		if _, ok := header[key]; !ok {
+			return
+		}
+		if excludeHeader == nil {
+			excludeHeader = make(map[string]bool)
+		}
+		excludeHeader[key] = true
+	}
+	var setHeader extraHeader
+
+	// Don't write out the fake "Trailer:foo" keys. See TrailerPrefix.
+	trailers := false
+	for k := range cw.header {
+		if strings.HasPrefix(k, TrailerPrefix) {
+			if excludeHeader == nil {
+				excludeHeader = make(map[string]bool)
+			}
+			excludeHeader[k] = true
+			trailers = true
+		}
+	}
+	for _, v := range cw.header["Trailer"] {
+		trailers = true
+		foreachHeaderElement(v, cw.res.declareTrailer)
+	}
+
+	te := header.get("Transfer-Encoding")
+	hasTE := te != ""
+
+	// If the handler is done but never sent a Content-Length
+	// response header and this is our first (and last) write, set
+	// it, even to zero. This helps HTTP/1.0 clients keep their
+	// "keep-alive" connections alive.
+	// Exceptions: 304/204/1xx responses never get Content-Length, and if
+	// it was a HEAD request, we don't know the difference between
+	// 0 actual bytes and 0 bytes because the handler noticed it
+	// was a HEAD request and chose not to write anything. So for
+	// HEAD, the handler should either write the Content-Length or
+	// write non-zero bytes. If it's actually 0 bytes and the
+	// handler never looked at the Request.Method, we just don't
+	// send a Content-Length header.
+	// Further, we don't send an automatic Content-Length if they
+	// set a Transfer-Encoding, because they're generally incompatible.
+	if w.handlerDone.isSet() && !trailers && !hasTE && bodyAllowedForStatus(w.status) && header.get("Content-Length") == "" && (!isHEAD || len(p) > 0) {
+		w.contentLength = int64(len(p))
+		setHeader.contentLength = strconv.AppendInt(cw.res.clenBuf[:0], int64(len(p)), 10)
+	}
+
+	// If this was an HTTP/1.0 request with keep-alive and we sent a
+	// Content-Length back, we can make this a keep-alive response ...
+	if w.wants10KeepAlive && keepAlivesEnabled {
+		sentLength := header.get("Content-Length") != ""
+		if sentLength && header.get("Connection") == "keep-alive" {
+			w.closeAfterReply = false
+		}
+	}
+
+	// Check for an explicit (and valid) Content-Length header.
+	hasCL := w.contentLength != -1
+
+	if w.wants10KeepAlive && (isHEAD || hasCL || !bodyAllowedForStatus(w.status)) {
+		_, connectionHeaderSet := header["Connection"]
+		if !connectionHeaderSet {
+			setHeader.connection = "keep-alive"
+		}
+	} else if !w.req.ProtoAtLeast(1, 1) || w.wantsClose {
+		w.closeAfterReply = true
+	}
+
+	if header.get("Connection") == "close" || !keepAlivesEnabled {
+		w.closeAfterReply = true
+	}
+
+	// If the client wanted a 100-continue but we never sent it to
+	// them (or, more strictly: we never finished reading their
+	// request body), don't reuse this connection because it's now
+	// in an unknown state: we might be sending this response at
+	// the same time the client is now sending its request body
+	// after a timeout.  (Some HTTP clients send Expect:
+	// 100-continue but knowing that some servers don't support
+	// it, the clients set a timer and send the body later anyway)
+	// If we haven't seen EOF, we can't skip over the unread body
+	// because we don't know if the next bytes on the wire will be
+	// the body-following-the-timer or the subsequent request.
+	// See Issue 11549.
+	if ecr, ok := w.req.Body.(*expectContinueReader); ok && !ecr.sawEOF.isSet() {
+		w.closeAfterReply = true
+	}
+
+	// Per RFC 2616, we should consume the request body before
+	// replying, if the handler hasn't already done so. But we
+	// don't want to do an unbounded amount of reading here for
+	// DoS reasons, so we only try up to a threshold.
+	// TODO(bradfitz): where does RFC 2616 say that? See Issue 15527
+	// about HTTP/1.x Handlers concurrently reading and writing, like
+	// HTTP/2 handlers can do. Maybe this code should be relaxed?
+	if w.req.ContentLength != 0 && !w.closeAfterReply {
+		var discard, tooBig bool
+
+		switch bdy := w.req.Body.(type) {
+		case *expectContinueReader:
+			if bdy.resp.wroteContinue {
+				discard = true
+			}
+		case *body:
+			bdy.mu.Lock()
+			switch {
+			case bdy.closed:
+				if !bdy.sawEOF {
+					// Body was closed in handler with non-EOF error.
+					w.closeAfterReply = true
+				}
+			case bdy.unreadDataSizeLocked() >= maxPostHandlerReadBytes:
+				tooBig = true
+			default:
+				discard = true
+			}
+			bdy.mu.Unlock()
+		default:
+			discard = true
+		}
+
+		if discard {
+			_, err := io.CopyN(io.Discard, w.reqBody, maxPostHandlerReadBytes+1)
+			switch err {
+			case nil:
+				// There must be even more data left over.
+				tooBig = true
+			case ErrBodyReadAfterClose:
+				// Body was already consumed and closed.
+			case io.EOF:
+				// The remaining body was just consumed, close it.
+				err = w.reqBody.Close()
+				if err != nil {
+					w.closeAfterReply = true
+				}
+			default:
+				// Some other kind of error occurred, like a read timeout, or
+				// corrupt chunked encoding. In any case, whatever remains
+				// on the wire must not be parsed as another HTTP request.
+				w.closeAfterReply = true
+			}
+		}
+
+		if tooBig {
+			w.requestTooLarge()
+			delHeader("Connection")
+			setHeader.connection = "close"
+		}
+	}
+
+	code := w.status
+	if bodyAllowedForStatus(code) {
+		// If no content type, apply sniffing algorithm to body.
+		_, haveType := header["Content-Type"]
+
+		// If the Content-Encoding was set and is non-blank,
+		// we shouldn't sniff the body. See Issue 31753.
+		ce := header.Get("Content-Encoding")
+		hasCE := len(ce) > 0
+		if !hasCE && !haveType && !hasTE && len(p) > 0 {
+			setHeader.contentType = DetectContentType(p)
+		}
+	} else {
+		for _, k := range suppressedHeaders(code) {
+			delHeader(k)
+		}
+	}
+
+	if !header.has("Date") {
+		setHeader.date = appendTime(cw.res.dateBuf[:0], time.Now())
+	}
+
+	if hasCL && hasTE && te != "identity" {
+		// TODO: return an error if WriteHeader gets a return parameter
+		// For now just ignore the Content-Length.
+		w.conn.server.logf("http: WriteHeader called with both Transfer-Encoding of %q and a Content-Length of %d",
+			te, w.contentLength)
+		delHeader("Content-Length")
+		hasCL = false
+	}
+
+	if w.req.Method == "HEAD" || !bodyAllowedForStatus(code) || code == StatusNoContent {
+		// Response has no body.
+		delHeader("Transfer-Encoding")
+	} else if hasCL {
+		// Content-Length has been provided, so no chunking is to be done.
+		delHeader("Transfer-Encoding")
+	} else if w.req.ProtoAtLeast(1, 1) {
+		// HTTP/1.1 or greater: Transfer-Encoding has been set to identity, and no
+		// content-length has been provided. The connection must be closed after the
+		// reply is written, and no chunking is to be done. This is the setup
+		// recommended in the Server-Sent Events candidate recommendation 11,
+		// section 8.
+		if hasTE && te == "identity" {
+			cw.chunking = false
+			w.closeAfterReply = true
+			delHeader("Transfer-Encoding")
+		} else {
+			// HTTP/1.1 or greater: use chunked transfer encoding
+			// to avoid closing the connection at EOF.
+			cw.chunking = true
+			setHeader.transferEncoding = "chunked"
+			if hasTE && te == "chunked" {
+				// We will send the chunked Transfer-Encoding header later.
+				delHeader("Transfer-Encoding")
+			}
+		}
+	} else {
+		// HTTP version < 1.1: cannot do chunked transfer
+		// encoding and we don't know the Content-Length so
+		// signal EOF by closing connection.
+		w.closeAfterReply = true
+		delHeader("Transfer-Encoding") // in case already set
+	}
+
+	// Cannot use Content-Length with non-identity Transfer-Encoding.
+	if cw.chunking {
+		delHeader("Content-Length")
+	}
+	if !w.req.ProtoAtLeast(1, 0) {
+		return
+	}
+
+	// Only override the Connection header if it is not a successful
+	// protocol switch response and if KeepAlives are not enabled.
+	// See https://golang.org/issue/36381.
+	delConnectionHeader := w.closeAfterReply &&
+		(!keepAlivesEnabled || !hasToken(cw.header.get("Connection"), "close")) &&
+		!isProtocolSwitchResponse(w.status, header)
+	if delConnectionHeader {
+		delHeader("Connection")
+		if w.req.ProtoAtLeast(1, 1) {
+			setHeader.connection = "close"
+		}
+	}
+
+	writeStatusLine(w.conn.bufw, w.req.ProtoAtLeast(1, 1), code, w.statusBuf[:])
+	cw.header.WriteSubset(w.conn.bufw, excludeHeader)
+	setHeader.Write(w.conn.bufw)
+	w.conn.bufw.Write(crlf)
+}
+
+// foreachHeaderElement splits v according to the "#rule" construction
+// in RFC 7230 section 7 and calls fn for each non-empty element.
+func foreachHeaderElement(v string, fn func(string)) {
+	v = textproto.TrimString(v)
+	if v == "" {
+		return
+	}
+	if !strings.Contains(v, ",") {
+		fn(v)
+		return
+	}
+	for _, f := range strings.Split(v, ",") {
+		if f = textproto.TrimString(f); f != "" {
+			fn(f)
+		}
+	}
+}
+
+// writeStatusLine writes an HTTP/1.x Status-Line (RFC 7230 Section 3.1.2)
+// to bw. is11 is whether the HTTP request is HTTP/1.1. false means HTTP/1.0.
+// code is the response status code.
+// scratch is an optional scratch buffer. If it has at least capacity 3, it's used.
+func writeStatusLine(bw *bufio.Writer, is11 bool, code int, scratch []byte) {
+	if is11 {
+		bw.WriteString("HTTP/1.1 ")
+	} else {
+		bw.WriteString("HTTP/1.0 ")
+	}
+	if text := StatusText(code); text != "" {
+		bw.Write(strconv.AppendInt(scratch[:0], int64(code), 10))
+		bw.WriteByte(' ')
+		bw.WriteString(text)
+		bw.WriteString("\r\n")
+	} else {
+		// don't worry about performance
+		fmt.Fprintf(bw, "%03d status code %d\r\n", code, code)
+	}
+}
+
+// bodyAllowed reports whether a Write is allowed for this response type.
+// It's illegal to call this before the header has been flushed.
+func (w *response) bodyAllowed() bool {
+	if !w.wroteHeader {
+		panic("")
+	}
+	return bodyAllowedForStatus(w.status)
+}
+
+// The Life Of A Write is like this:
+//
+// Handler starts. No header has been sent. The handler can either
+// write a header, or just start writing. Writing before sending a header
+// sends an implicitly empty 200 OK header.
+//
+// If the handler didn't declare a Content-Length up front, we either
+// go into chunking mode or, if the handler finishes running before
+// the chunking buffer size, we compute a Content-Length and send that
+// in the header instead.
+//
+// Likewise, if the handler didn't set a Content-Type, we sniff that
+// from the initial chunk of output.
+//
+// The Writers are wired together like:
+//
+//  1. *response (the ResponseWriter) ->
+//  2. (*response).w, a *bufio.Writer of bufferBeforeChunkingSize bytes ->
+//  3. chunkWriter.Writer (whose writeHeader finalizes Content-Length/Type)
+//     and which writes the chunk headers, if needed ->
+//  4. conn.bufw, a *bufio.Writer of default (4kB) bytes, writing to ->
+//  5. checkConnErrorWriter{c}, which notes any non-nil error on Write
+//     and populates c.werr with it if so, but otherwise writes to ->
+//  6. the rwc, the net.Conn.
+//
+// TODO(bradfitz): short-circuit some of the buffering when the
+// initial header contains both a Content-Type and Content-Length.
+// Also short-circuit in (1) when the header's been sent and not in
+// chunking mode, writing directly to (4) instead, if (2) has no
+// buffered data. More generally, we could short-circuit from (1) to
+// (3) even in chunking mode if the write size from (1) is over some
+// threshold and nothing is in (2).  The answer might be mostly making
+// bufferBeforeChunkingSize smaller and having bufio's fast-paths deal
+// with this instead.
+func (w *response) Write(data []byte) (n int, err error) {
+	return w.write(len(data), data, "")
+}
+
+func (w *response) WriteString(data string) (n int, err error) {
+	return w.write(len(data), nil, data)
+}
+
+// either dataB or dataS is non-zero.
+func (w *response) write(lenData int, dataB []byte, dataS string) (n int, err error) {
+	if w.conn.hijacked() {
+		if lenData > 0 {
+			caller := relevantCaller()
+			w.conn.server.logf("http: response.Write on hijacked connection from %s (%s:%d)", caller.Function, path.Base(caller.File), caller.Line)
+		}
+		return 0, ErrHijacked
+	}
+
+	if w.canWriteContinue.isSet() {
+		// Body reader wants to write 100 Continue but hasn't yet.
+		// Tell it not to. The store must be done while holding the lock
+		// because the lock makes sure that there is not an active write
+		// this very moment.
+		w.writeContinueMu.Lock()
+		w.canWriteContinue.setFalse()
+		w.writeContinueMu.Unlock()
+	}
+
+	if !w.wroteHeader {
+		w.WriteHeader(StatusOK)
+	}
+	if lenData == 0 {
+		return 0, nil
+	}
+	if !w.bodyAllowed() {
+		return 0, ErrBodyNotAllowed
+	}
+
+	w.written += int64(lenData) // ignoring errors, for errorKludge
+	if w.contentLength != -1 && w.written > w.contentLength {
+		return 0, ErrContentLength
+	}
+	if dataB != nil {
+		return w.w.Write(dataB)
+	} else {
+		return w.w.WriteString(dataS)
+	}
+}
+
+func (w *response) finishRequest() {
+	w.handlerDone.setTrue()
+
+	if !w.wroteHeader {
+		w.WriteHeader(StatusOK)
+	}
+
+	w.w.Flush()
+	putBufioWriter(w.w)
+	w.cw.close()
+	w.conn.bufw.Flush()
+
+	w.conn.r.abortPendingRead()
+
+	// Close the body (regardless of w.closeAfterReply) so we can
+	// re-use its bufio.Reader later safely.
+	w.reqBody.Close()
+
+	if w.req.MultipartForm != nil {
+		w.req.MultipartForm.RemoveAll()
+	}
+}
+
+// shouldReuseConnection reports whether the underlying TCP connection can be reused.
+// It must only be called after the handler is done executing.
+func (w *response) shouldReuseConnection() bool {
+	if w.closeAfterReply {
+		// The request or something set while executing the
+		// handler indicated we shouldn't reuse this
+		// connection.
+		return false
+	}
+
+	if w.req.Method != "HEAD" && w.contentLength != -1 && w.bodyAllowed() && w.contentLength != w.written {
+		// Did not write enough. Avoid getting out of sync.
+		return false
+	}
+
+	// There was some error writing to the underlying connection
+	// during the request, so don't re-use this conn.
+	if w.conn.werr != nil {
+		return false
+	}
+
+	if w.closedRequestBodyEarly() {
+		return false
+	}
+
+	return true
+}
+
+func (w *response) closedRequestBodyEarly() bool {
+	body, ok := w.req.Body.(*body)
+	return ok && body.didEarlyClose()
+}
+
+func (w *response) Flush() {
+	if !w.wroteHeader {
+		w.WriteHeader(StatusOK)
+	}
+	w.w.Flush()
+	w.cw.flush()
+}
+
+func (c *conn) finalFlush() {
+	if c.bufr != nil {
+		// Steal the bufio.Reader (~4KB worth of memory) and its associated
+		// reader for a future connection.
+		putBufioReader(c.bufr)
+		c.bufr = nil
+	}
+
+	if c.bufw != nil {
+		c.bufw.Flush()
+		// Steal the bufio.Writer (~4KB worth of memory) and its associated
+		// writer for a future connection.
+		putBufioWriter(c.bufw)
+		c.bufw = nil
+	}
+}
+
+// Close the connection.
+func (c *conn) close() {
+	c.finalFlush()
+	c.rwc.Close()
+}
+
+// rstAvoidanceDelay is the amount of time we sleep after closing the
+// write side of a TCP connection before closing the entire socket.
+// By sleeping, we increase the chances that the client sees our FIN
+// and processes its final data before they process the subsequent RST
+// from closing a connection with known unread data.
+// This RST seems to occur mostly on BSD systems. (And Windows?)
+// This timeout is somewhat arbitrary (~latency around the planet).
+const rstAvoidanceDelay = 500 * time.Millisecond
+
+type closeWriter interface {
+	CloseWrite() error
+}
+
+var _ closeWriter = (*net.TCPConn)(nil)
+
+// closeWrite flushes any outstanding data and sends a FIN packet (if
+// client is connected via TCP), signaling that we're done. We then
+// pause for a bit, hoping the client processes it before any
+// subsequent RST.
+//
+// See https://golang.org/issue/3595
+func (c *conn) closeWriteAndWait() {
+	c.finalFlush()
+	if tcp, ok := c.rwc.(closeWriter); ok {
+		tcp.CloseWrite()
+	}
+	time.Sleep(rstAvoidanceDelay)
+}
+
+// validNextProto reports whether the proto is a valid ALPN protocol name.
+// Everything is valid except the empty string and built-in protocol types,
+// so that those can't be overridden with alternate implementations.
+func validNextProto(proto string) bool {
+	switch proto {
+	case "", "http/1.1", "http/1.0":
+		return false
+	}
+	return true
+}
+
+const (
+	runHooks  = true
+	skipHooks = false
+)
+
+func (c *conn) setState(nc net.Conn, state ConnState, runHook bool) {
+	srv := c.server
+	switch state {
+	case StateNew:
+		srv.trackConn(c, true)
+	case StateHijacked, StateClosed:
+		srv.trackConn(c, false)
+	}
+	if state > 0xff || state < 0 {
+		panic("internal error")
+	}
+	packedState := uint64(time.Now().Unix()<<8) | uint64(state)
+	atomic.StoreUint64(&c.curState.atomic, packedState)
+	if !runHook {
+		return
+	}
+	if hook := srv.ConnState; hook != nil {
+		hook(nc, state)
+	}
+}
+
+func (c *conn) getState() (state ConnState, unixSec int64) {
+	packedState := atomic.LoadUint64(&c.curState.atomic)
+	return ConnState(packedState & 0xff), int64(packedState >> 8)
+}
+
+// badRequestError is a literal string (used by in the server in HTML,
+// unescaped) to tell the user why their request was bad. It should
+// be plain text without user info or other embedded errors.
+func badRequestError(e string) error { return statusError{StatusBadRequest, e} }
+
+// statusError is an error used to respond to a request with an HTTP status.
+// The text should be plain text without user info or other embedded errors.
+type statusError struct {
+	code int
+	text string
+}
+
+func (e statusError) Error() string { return StatusText(e.code) + ": " + e.text }
+
+// ErrAbortHandler is a sentinel panic value to abort a handler.
+// While any panic from ServeHTTP aborts the response to the client,
+// panicking with ErrAbortHandler also suppresses logging of a stack
+// trace to the server's error log.
+var ErrAbortHandler = errors.New("net/http: abort Handler")
+
+// isCommonNetReadError reports whether err is a common error
+// encountered during reading a request off the network when the
+// client has gone away or had its read fail somehow. This is used to
+// determine which logs are interesting enough to log about.
+func isCommonNetReadError(err error) bool {
+	if err == io.EOF {
+		return true
+	}
+	if neterr, ok := err.(net.Error); ok && neterr.Timeout() {
+		return true
+	}
+	if oe, ok := err.(*net.OpError); ok && oe.Op == "read" {
+		return true
+	}
+	return false
+}
+
+// Serve a new connection.
+func (c *conn) serve(ctx context.Context) {
+	c.remoteAddr = c.rwc.RemoteAddr().String()
+	ctx = context.WithValue(ctx, LocalAddrContextKey, c.rwc.LocalAddr())
+	var inFlightResponse *response
+	defer func() {
+		if err := recover(); err != nil && err != ErrAbortHandler {
+			const size = 64 << 10
+			buf := make([]byte, size)
+			buf = buf[:runtime.Stack(buf, false)]
+			c.server.logf("http: panic serving %v: %v\n%s", c.remoteAddr, err, buf)
+		}
+		if inFlightResponse != nil {
+			inFlightResponse.cancelCtx()
+		}
+		if !c.hijacked() {
+			if inFlightResponse != nil {
+				inFlightResponse.conn.r.abortPendingRead()
+				inFlightResponse.reqBody.Close()
+			}
+			c.close()
+			c.setState(c.rwc, StateClosed, runHooks)
+		}
+	}()
+
+	if tlsConn, ok := c.rwc.(*tls.Conn); ok {
+		tlsTO := c.server.tlsHandshakeTimeout()
+		if tlsTO > 0 {
+			dl := time.Now().Add(tlsTO)
+			c.rwc.SetReadDeadline(dl)
+			c.rwc.SetWriteDeadline(dl)
+		}
+		if err := tlsConn.HandshakeContext(ctx); err != nil {
+			// If the handshake failed due to the client not speaking
+			// TLS, assume they're speaking plaintext HTTP and write a
+			// 400 response on the TLS conn's underlying net.Conn.
+			if re, ok := err.(tls.RecordHeaderError); ok && re.Conn != nil && tlsRecordHeaderLooksLikeHTTP(re.RecordHeader) {
+				io.WriteString(re.Conn, "HTTP/1.0 400 Bad Request\r\n\r\nClient sent an HTTP request to an HTTPS server.\n")
+				re.Conn.Close()
+				return
+			}
+			c.server.logf("http: TLS handshake error from %s: %v", c.rwc.RemoteAddr(), err)
+			return
+		}
+		// Restore Conn-level deadlines.
+		if tlsTO > 0 {
+			c.rwc.SetReadDeadline(time.Time{})
+			c.rwc.SetWriteDeadline(time.Time{})
+		}
+		c.tlsState = new(tls.ConnectionState)
+		*c.tlsState = tlsConn.ConnectionState()
+		if proto := c.tlsState.NegotiatedProtocol; validNextProto(proto) {
+			if fn := c.server.TLSNextProto[proto]; fn != nil {
+				h := initALPNRequest{ctx, tlsConn, serverHandler{c.server}}
+				// Mark freshly created HTTP/2 as active and prevent any server state hooks
+				// from being run on these connections. This prevents closeIdleConns from
+				// closing such connections. See issue https://golang.org/issue/39776.
+				c.setState(c.rwc, StateActive, skipHooks)
+				fn(c.server, tlsConn, h)
+			}
+			return
+		}
+	}
+
+	// HTTP/1.x from here on.
+
+	ctx, cancelCtx := context.WithCancel(ctx)
+	c.cancelCtx = cancelCtx
+	defer cancelCtx()
+
+	c.r = &connReader{conn: c}
+	c.bufr = newBufioReader(c.r)
+	c.bufw = newBufioWriterSize(checkConnErrorWriter{c}, 4<<10)
+
+	for {
+		w, err := c.readRequest(ctx)
+		if c.r.remain != c.server.initialReadLimitSize() {
+			// If we read any bytes off the wire, we're active.
+			c.setState(c.rwc, StateActive, runHooks)
+		}
+		if err != nil {
+			const errorHeaders = "\r\nContent-Type: text/plain; charset=utf-8\r\nConnection: close\r\n\r\n"
+
+			switch {
+			case err == errTooLarge:
+				// Their HTTP client may or may not be
+				// able to read this if we're
+				// responding to them and hanging up
+				// while they're still writing their
+				// request. Undefined behavior.
+				const publicErr = "431 Request Header Fields Too Large"
+				fmt.Fprintf(c.rwc, "HTTP/1.1 "+publicErr+errorHeaders+publicErr)
+				c.closeWriteAndWait()
+				return
+
+			case isUnsupportedTEError(err):
+				// Respond as per RFC 7230 Section 3.3.1 which says,
+				//      A server that receives a request message with a
+				//      transfer coding it does not understand SHOULD
+				//      respond with 501 (Unimplemented).
+				code := StatusNotImplemented
+
+				// We purposefully aren't echoing back the transfer-encoding's value,
+				// so as to mitigate the risk of cross side scripting by an attacker.
+				fmt.Fprintf(c.rwc, "HTTP/1.1 %d %s%sUnsupported transfer encoding", code, StatusText(code), errorHeaders)
+				return
+
+			case isCommonNetReadError(err):
+				return // don't reply
+
+			default:
+				if v, ok := err.(statusError); ok {
+					fmt.Fprintf(c.rwc, "HTTP/1.1 %d %s: %s%s%d %s: %s", v.code, StatusText(v.code), v.text, errorHeaders, v.code, StatusText(v.code), v.text)
+					return
+				}
+				publicErr := "400 Bad Request"
+				fmt.Fprintf(c.rwc, "HTTP/1.1 "+publicErr+errorHeaders+publicErr)
+				return
+			}
+		}
+
+		// Expect 100 Continue support
+		req := w.req
+		if req.expectsContinue() {
+			if req.ProtoAtLeast(1, 1) && req.ContentLength != 0 {
+				// Wrap the Body reader with one that replies on the connection
+				req.Body = &expectContinueReader{readCloser: req.Body, resp: w}
+				w.canWriteContinue.setTrue()
+			}
+		} else if req.Header.get("Expect") != "" {
+			w.sendExpectationFailed()
+			return
+		}
+
+		c.curReq.Store(w)
+
+		if requestBodyRemains(req.Body) {
+			registerOnHitEOF(req.Body, w.conn.r.startBackgroundRead)
+		} else {
+			w.conn.r.startBackgroundRead()
+		}
+
+		// HTTP cannot have multiple simultaneous active requests.[*]
+		// Until the server replies to this request, it can't read another,
+		// so we might as well run the handler in this goroutine.
+		// [*] Not strictly true: HTTP pipelining. We could let them all process
+		// in parallel even if their responses need to be serialized.
+		// But we're not going to implement HTTP pipelining because it
+		// was never deployed in the wild and the answer is HTTP/2.
+		inFlightResponse = w
+		serverHandler{c.server}.ServeHTTP(w, w.req)
+		inFlightResponse = nil
+		w.cancelCtx()
+		if c.hijacked() {
+			return
+		}
+		w.finishRequest()
+		if !w.shouldReuseConnection() {
+			if w.requestBodyLimitHit || w.closedRequestBodyEarly() {
+				c.closeWriteAndWait()
+			}
+			return
+		}
+		c.setState(c.rwc, StateIdle, runHooks)
+		c.curReq.Store((*response)(nil))
+
+		if !w.conn.server.doKeepAlives() {
+			// We're in shutdown mode. We might've replied
+			// to the user without "Connection: close" and
+			// they might think they can send another
+			// request, but such is life with HTTP/1.1.
+			return
+		}
+
+		if d := c.server.idleTimeout(); d != 0 {
+			c.rwc.SetReadDeadline(time.Now().Add(d))
+			if _, err := c.bufr.Peek(4); err != nil {
+				return
+			}
+		}
+		c.rwc.SetReadDeadline(time.Time{})
+	}
+}
+
+func (w *response) sendExpectationFailed() {
+	// TODO(bradfitz): let ServeHTTP handlers handle
+	// requests with non-standard expectation[s]? Seems
+	// theoretical at best, and doesn't fit into the
+	// current ServeHTTP model anyway. We'd need to
+	// make the ResponseWriter an optional
+	// "ExpectReplier" interface or something.
+	//
+	// For now we'll just obey RFC 7231 5.1.1 which says
+	// "A server that receives an Expect field-value other
+	// than 100-continue MAY respond with a 417 (Expectation
+	// Failed) status code to indicate that the unexpected
+	// expectation cannot be met."
+	w.Header().Set("Connection", "close")
+	w.WriteHeader(StatusExpectationFailed)
+	w.finishRequest()
+}
+
+// Hijack implements the Hijacker.Hijack method. Our response is both a ResponseWriter
+// and a Hijacker.
+func (w *response) Hijack() (rwc net.Conn, buf *bufio.ReadWriter, err error) {
+	if w.handlerDone.isSet() {
+		panic("net/http: Hijack called after ServeHTTP finished")
+	}
+	if w.wroteHeader {
+		w.cw.flush()
+	}
+
+	c := w.conn
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	// Release the bufioWriter that writes to the chunk writer, it is not
+	// used after a connection has been hijacked.
+	rwc, buf, err = c.hijackLocked()
+	if err == nil {
+		putBufioWriter(w.w)
+		w.w = nil
+	}
+	return rwc, buf, err
+}
+
+func (w *response) CloseNotify() <-chan bool {
+	if w.handlerDone.isSet() {
+		panic("net/http: CloseNotify called after ServeHTTP finished")
+	}
+	return w.closeNotifyCh
+}
+
+func registerOnHitEOF(rc io.ReadCloser, fn func()) {
+	switch v := rc.(type) {
+	case *expectContinueReader:
+		registerOnHitEOF(v.readCloser, fn)
+	case *body:
+		v.registerOnHitEOF(fn)
+	default:
+		panic("unexpected type " + fmt.Sprintf("%T", rc))
+	}
+}
+
+// requestBodyRemains reports whether future calls to Read
+// on rc might yield more data.
+func requestBodyRemains(rc io.ReadCloser) bool {
+	if rc == NoBody {
+		return false
+	}
+	switch v := rc.(type) {
+	case *expectContinueReader:
+		return requestBodyRemains(v.readCloser)
+	case *body:
+		return v.bodyRemains()
+	default:
+		panic("unexpected type " + fmt.Sprintf("%T", rc))
+	}
+}
+
+// The HandlerFunc type is an adapter to allow the use of
+// ordinary functions as HTTP handlers. If f is a function
+// with the appropriate signature, HandlerFunc(f) is a
+// Handler that calls f.
+type HandlerFunc func(ResponseWriter, *Request)
+
+// ServeHTTP calls f(w, r).
+func (f HandlerFunc) ServeHTTP(w ResponseWriter, r *Request) {
+	f(w, r)
+}
+
+// Helper handlers
+
+// Error replies to the request with the specified error message and HTTP code.
+// It does not otherwise end the request; the caller should ensure no further
+// writes are done to w.
+// The error message should be plain text.
+func Error(w ResponseWriter, error string, code int) {
+	w.Header().Set("Content-Type", "text/plain; charset=utf-8")
+	w.Header().Set("X-Content-Type-Options", "nosniff")
+	w.WriteHeader(code)
+	fmt.Fprintln(w, error)
+}
+
+// NotFound replies to the request with an HTTP 404 not found error.
+func NotFound(w ResponseWriter, r *Request) { Error(w, "404 page not found", StatusNotFound) }
+
+// NotFoundHandler returns a simple request handler
+// that replies to each request with a “404 page not found” reply.
+func NotFoundHandler() Handler { return HandlerFunc(NotFound) }
+
+// StripPrefix returns a handler that serves HTTP requests by removing the
+// given prefix from the request URL's Path (and RawPath if set) and invoking
+// the handler h. StripPrefix handles a request for a path that doesn't begin
+// with prefix by replying with an HTTP 404 not found error. The prefix must
+// match exactly: if the prefix in the request contains escaped characters
+// the reply is also an HTTP 404 not found error.
+func StripPrefix(prefix string, h Handler) Handler {
+	if prefix == "" {
+		return h
+	}
+	return HandlerFunc(func(w ResponseWriter, r *Request) {
+		p := strings.TrimPrefix(r.URL.Path, prefix)
+		rp := strings.TrimPrefix(r.URL.RawPath, prefix)
+		if len(p) < len(r.URL.Path) && (r.URL.RawPath == "" || len(rp) < len(r.URL.RawPath)) {
+			r2 := new(Request)
+			*r2 = *r
+			r2.URL = new(url.URL)
+			*r2.URL = *r.URL
+			r2.URL.Path = p
+			r2.URL.RawPath = rp
+			h.ServeHTTP(w, r2)
+		} else {
+			NotFound(w, r)
+		}
+	})
+}
+
+// Redirect replies to the request with a redirect to url,
+// which may be a path relative to the request path.
+//
+// The provided code should be in the 3xx range and is usually
+// StatusMovedPermanently, StatusFound or StatusSeeOther.
+//
+// If the Content-Type header has not been set, Redirect sets it
+// to "text/html; charset=utf-8" and writes a small HTML body.
+// Setting the Content-Type header to any value, including nil,
+// disables that behavior.
+func Redirect(w ResponseWriter, r *Request, url string, code int) {
+	if u, err := urlpkg.Parse(url); err == nil {
+		// If url was relative, make its path absolute by
+		// combining with request path.
+		// The client would probably do this for us,
+		// but doing it ourselves is more reliable.
+		// See RFC 7231, section 7.1.2
+		if u.Scheme == "" && u.Host == "" {
+			oldpath := r.URL.Path
+			if oldpath == "" { // should not happen, but avoid a crash if it does
+				oldpath = "/"
+			}
+
+			// no leading http://server
+			if url == "" || url[0] != '/' {
+				// make relative path absolute
+				olddir, _ := path.Split(oldpath)
+				url = olddir + url
+			}
+
+			var query string
+			if i := strings.Index(url, "?"); i != -1 {
+				url, query = url[:i], url[i:]
+			}
+
+			// clean up but preserve trailing slash
+			trailing := strings.HasSuffix(url, "/")
+			url = path.Clean(url)
+			if trailing && !strings.HasSuffix(url, "/") {
+				url += "/"
+			}
+			url += query
+		}
+	}
+
+	h := w.Header()
+
+	// RFC 7231 notes that a short HTML body is usually included in
+	// the response because older user agents may not understand 301/307.
+	// Do it only if the request didn't already have a Content-Type header.
+	_, hadCT := h["Content-Type"]
+
+	h.Set("Location", hexEscapeNonASCII(url))
+	if !hadCT && (r.Method == "GET" || r.Method == "HEAD") {
+		h.Set("Content-Type", "text/html; charset=utf-8")
+	}
+	w.WriteHeader(code)
+
+	// Shouldn't send the body for POST or HEAD; that leaves GET.
+	if !hadCT && r.Method == "GET" {
+		body := "<a href=\"" + htmlEscape(url) + "\">" + StatusText(code) + "</a>.\n"
+		fmt.Fprintln(w, body)
+	}
+}
+
+var htmlReplacer = strings.NewReplacer(
+	"&", "&amp;",
+	"<", "&lt;",
+	">", "&gt;",
+	// "&#34;" is shorter than "&quot;".
+	`"`, "&#34;",
+	// "&#39;" is shorter than "&apos;" and apos was not in HTML until HTML5.
+	"'", "&#39;",
+)
+
+func htmlEscape(s string) string {
+	return htmlReplacer.Replace(s)
+}
+
+// Redirect to a fixed URL
+type redirectHandler struct {
+	url  string
+	code int
+}
+
+func (rh *redirectHandler) ServeHTTP(w ResponseWriter, r *Request) {
+	Redirect(w, r, rh.url, rh.code)
+}
+
+// RedirectHandler returns a request handler that redirects
+// each request it receives to the given url using the given
+// status code.
+//
+// The provided code should be in the 3xx range and is usually
+// StatusMovedPermanently, StatusFound or StatusSeeOther.
+func RedirectHandler(url string, code int) Handler {
+	return &redirectHandler{url, code}
+}
+
+// ServeMux is an HTTP request multiplexer.
+// It matches the URL of each incoming request against a list of registered
+// patterns and calls the handler for the pattern that
+// most closely matches the URL.
+//
+// Patterns name fixed, rooted paths, like "/favicon.ico",
+// or rooted subtrees, like "/images/" (note the trailing slash).
+// Longer patterns take precedence over shorter ones, so that
+// if there are handlers registered for both "/images/"
+// and "/images/thumbnails/", the latter handler will be
+// called for paths beginning "/images/thumbnails/" and the
+// former will receive requests for any other paths in the
+// "/images/" subtree.
+//
+// Note that since a pattern ending in a slash names a rooted subtree,
+// the pattern "/" matches all paths not matched by other registered
+// patterns, not just the URL with Path == "/".
+//
+// If a subtree has been registered and a request is received naming the
+// subtree root without its trailing slash, ServeMux redirects that
+// request to the subtree root (adding the trailing slash). This behavior can
+// be overridden with a separate registration for the path without
+// the trailing slash. For example, registering "/images/" causes ServeMux
+// to redirect a request for "/images" to "/images/", unless "/images" has
+// been registered separately.
+//
+// Patterns may optionally begin with a host name, restricting matches to
+// URLs on that host only. Host-specific patterns take precedence over
+// general patterns, so that a handler might register for the two patterns
+// "/codesearch" and "codesearch.google.com/" without also taking over
+// requests for "http://www.google.com/".
+//
+// ServeMux also takes care of sanitizing the URL request path and the Host
+// header, stripping the port number and redirecting any request containing . or
+// .. elements or repeated slashes to an equivalent, cleaner URL.
+type ServeMux struct {
+	mu    sync.RWMutex
+	m     map[string]muxEntry
+	es    []muxEntry // slice of entries sorted from longest to shortest.
+	hosts bool       // whether any patterns contain hostnames
+}
+
+type muxEntry struct {
+	h       Handler
+	pattern string
+}
+
+// NewServeMux allocates and returns a new ServeMux.
+func NewServeMux() *ServeMux { return new(ServeMux) }
+
+// DefaultServeMux is the default ServeMux used by Serve.
+var DefaultServeMux = &defaultServeMux
+
+var defaultServeMux ServeMux
+
+// cleanPath returns the canonical path for p, eliminating . and .. elements.
+func cleanPath(p string) string {
+	if p == "" {
+		return "/"
+	}
+	if p[0] != '/' {
+		p = "/" + p
+	}
+	np := path.Clean(p)
+	// path.Clean removes trailing slash except for root;
+	// put the trailing slash back if necessary.
+	if p[len(p)-1] == '/' && np != "/" {
+		// Fast path for common case of p being the string we want:
+		if len(p) == len(np)+1 && strings.HasPrefix(p, np) {
+			np = p
+		} else {
+			np += "/"
+		}
+	}
+	return np
+}
+
+// stripHostPort returns h without any trailing ":<port>".
+func stripHostPort(h string) string {
+	// If no port on host, return unchanged
+	if !strings.Contains(h, ":") {
+		return h
+	}
+	host, _, err := net.SplitHostPort(h)
+	if err != nil {
+		return h // on error, return unchanged
+	}
+	return host
+}
+
+// Find a handler on a handler map given a path string.
+// Most-specific (longest) pattern wins.
+func (mux *ServeMux) match(path string) (h Handler, pattern string) {
+	// Check for exact match first.
+	v, ok := mux.m[path]
+	if ok {
+		return v.h, v.pattern
+	}
+
+	// Check for longest valid match.  mux.es contains all patterns
+	// that end in / sorted from longest to shortest.
+	for _, e := range mux.es {
+		if strings.HasPrefix(path, e.pattern) {
+			return e.h, e.pattern
+		}
+	}
+	return nil, ""
+}
+
+// redirectToPathSlash determines if the given path needs appending "/" to it.
+// This occurs when a handler for path + "/" was already registered, but
+// not for path itself. If the path needs appending to, it creates a new
+// URL, setting the path to u.Path + "/" and returning true to indicate so.
+func (mux *ServeMux) redirectToPathSlash(host, path string, u *url.URL) (*url.URL, bool) {
+	mux.mu.RLock()
+	shouldRedirect := mux.shouldRedirectRLocked(host, path)
+	mux.mu.RUnlock()
+	if !shouldRedirect {
+		return u, false
+	}
+	path = path + "/"
+	u = &url.URL{Path: path, RawQuery: u.RawQuery}
+	return u, true
+}
+
+// shouldRedirectRLocked reports whether the given path and host should be redirected to
+// path+"/". This should happen if a handler is registered for path+"/" but
+// not path -- see comments at ServeMux.
+func (mux *ServeMux) shouldRedirectRLocked(host, path string) bool {
+	p := []string{path, host + path}
+
+	for _, c := range p {
+		if _, exist := mux.m[c]; exist {
+			return false
+		}
+	}
+
+	n := len(path)
+	if n == 0 {
+		return false
+	}
+	for _, c := range p {
+		if _, exist := mux.m[c+"/"]; exist {
+			return path[n-1] != '/'
+		}
+	}
+
+	return false
+}
+
+// Handler returns the handler to use for the given request,
+// consulting r.Method, r.Host, and r.URL.Path. It always returns
+// a non-nil handler. If the path is not in its canonical form, the
+// handler will be an internally-generated handler that redirects
+// to the canonical path. If the host contains a port, it is ignored
+// when matching handlers.
+//
+// The path and host are used unchanged for CONNECT requests.
+//
+// Handler also returns the registered pattern that matches the
+// request or, in the case of internally-generated redirects,
+// the pattern that will match after following the redirect.
+//
+// If there is no registered handler that applies to the request,
+// Handler returns a “page not found” handler and an empty pattern.
+func (mux *ServeMux) Handler(r *Request) (h Handler, pattern string) {
+
+	// CONNECT requests are not canonicalized.
+	if r.Method == "CONNECT" {
+		// If r.URL.Path is /tree and its handler is not registered,
+		// the /tree -> /tree/ redirect applies to CONNECT requests
+		// but the path canonicalization does not.
+		if u, ok := mux.redirectToPathSlash(r.URL.Host, r.URL.Path, r.URL); ok {
+			return RedirectHandler(u.String(), StatusMovedPermanently), u.Path
+		}
+
+		return mux.handler(r.Host, r.URL.Path)
+	}
+
+	// All other requests have any port stripped and path cleaned
+	// before passing to mux.handler.
+	host := stripHostPort(r.Host)
+	path := cleanPath(r.URL.Path)
+
+	// If the given path is /tree and its handler is not registered,
+	// redirect for /tree/.
+	if u, ok := mux.redirectToPathSlash(host, path, r.URL); ok {
+		return RedirectHandler(u.String(), StatusMovedPermanently), u.Path
+	}
+
+	if path != r.URL.Path {
+		_, pattern = mux.handler(host, path)
+		u := &url.URL{Path: path, RawQuery: r.URL.RawQuery}
+		return RedirectHandler(u.String(), StatusMovedPermanently), pattern
+	}
+
+	return mux.handler(host, r.URL.Path)
+}
+
+// handler is the main implementation of Handler.
+// The path is known to be in canonical form, except for CONNECT methods.
+func (mux *ServeMux) handler(host, path string) (h Handler, pattern string) {
+	mux.mu.RLock()
+	defer mux.mu.RUnlock()
+
+	// Host-specific pattern takes precedence over generic ones
+	if mux.hosts {
+		h, pattern = mux.match(host + path)
+	}
+	if h == nil {
+		h, pattern = mux.match(path)
+	}
+	if h == nil {
+		h, pattern = NotFoundHandler(), ""
+	}
+	return
+}
+
+// ServeHTTP dispatches the request to the handler whose
+// pattern most closely matches the request URL.
+func (mux *ServeMux) ServeHTTP(w ResponseWriter, r *Request) {
+	if r.RequestURI == "*" {
+		if r.ProtoAtLeast(1, 1) {
+			w.Header().Set("Connection", "close")
+		}
+		w.WriteHeader(StatusBadRequest)
+		return
+	}
+	h, _ := mux.Handler(r)
+	h.ServeHTTP(w, r)
+}
+
+// Handle registers the handler for the given pattern.
+// If a handler already exists for pattern, Handle panics.
+func (mux *ServeMux) Handle(pattern string, handler Handler) {
+	mux.mu.Lock()
+	defer mux.mu.Unlock()
+
+	if pattern == "" {
+		panic("http: invalid pattern")
+	}
+	if handler == nil {
+		panic("http: nil handler")
+	}
+	if _, exist := mux.m[pattern]; exist {
+		panic("http: multiple registrations for " + pattern)
+	}
+
+	if mux.m == nil {
+		mux.m = make(map[string]muxEntry)
+	}
+	e := muxEntry{h: handler, pattern: pattern}
+	mux.m[pattern] = e
+	if pattern[len(pattern)-1] == '/' {
+		mux.es = appendSorted(mux.es, e)
+	}
+
+	if pattern[0] != '/' {
+		mux.hosts = true
+	}
+}
+
+func appendSorted(es []muxEntry, e muxEntry) []muxEntry {
+	n := len(es)
+	i := sort.Search(n, func(i int) bool {
+		return len(es[i].pattern) < len(e.pattern)
+	})
+	if i == n {
+		return append(es, e)
+	}
+	// we now know that i points at where we want to insert
+	es = append(es, muxEntry{}) // try to grow the slice in place, any entry works.
+	copy(es[i+1:], es[i:])      // Move shorter entries down
+	es[i] = e
+	return es
+}
+
+// HandleFunc registers the handler function for the given pattern.
+func (mux *ServeMux) HandleFunc(pattern string, handler func(ResponseWriter, *Request)) {
+	if handler == nil {
+		panic("http: nil handler")
+	}
+	mux.Handle(pattern, HandlerFunc(handler))
+}
+
+// Handle registers the handler for the given pattern
+// in the DefaultServeMux.
+// The documentation for ServeMux explains how patterns are matched.
+func Handle(pattern string, handler Handler) { DefaultServeMux.Handle(pattern, handler) }
+
+// HandleFunc registers the handler function for the given pattern
+// in the DefaultServeMux.
+// The documentation for ServeMux explains how patterns are matched.
+func HandleFunc(pattern string, handler func(ResponseWriter, *Request)) {
+	DefaultServeMux.HandleFunc(pattern, handler)
+}
+
+// Serve accepts incoming HTTP connections on the listener l,
+// creating a new service goroutine for each. The service goroutines
+// read requests and then call handler to reply to them.
+//
+// The handler is typically nil, in which case the DefaultServeMux is used.
+//
+// HTTP/2 support is only enabled if the Listener returns *tls.Conn
+// connections and they were configured with "h2" in the TLS
+// Config.NextProtos.
+//
+// Serve always returns a non-nil error.
+func Serve(l net.Listener, handler Handler) error {
+	srv := &Server{Handler: handler}
+	return srv.Serve(l)
+}
+
+// ServeTLS accepts incoming HTTPS connections on the listener l,
+// creating a new service goroutine for each. The service goroutines
+// read requests and then call handler to reply to them.
+//
+// The handler is typically nil, in which case the DefaultServeMux is used.
+//
+// Additionally, files containing a certificate and matching private key
+// for the server must be provided. If the certificate is signed by a
+// certificate authority, the certFile should be the concatenation
+// of the server's certificate, any intermediates, and the CA's certificate.
+//
+// ServeTLS always returns a non-nil error.
+func ServeTLS(l net.Listener, handler Handler, certFile, keyFile string) error {
+	srv := &Server{Handler: handler}
+	return srv.ServeTLS(l, certFile, keyFile)
+}
+
+// A Server defines parameters for running an HTTP server.
+// The zero value for Server is a valid configuration.
+type Server struct {
+	// Addr optionally specifies the TCP address for the server to listen on,
+	// in the form "host:port". If empty, ":http" (port 80) is used.
+	// The service names are defined in RFC 6335 and assigned by IANA.
+	// See net.Dial for details of the address format.
+	Addr string
+
+	Handler Handler // handler to invoke, http.DefaultServeMux if nil
+
+	// TLSConfig optionally provides a TLS configuration for use
+	// by ServeTLS and ListenAndServeTLS. Note that this value is
+	// cloned by ServeTLS and ListenAndServeTLS, so it's not
+	// possible to modify the configuration with methods like
+	// tls.Config.SetSessionTicketKeys. To use
+	// SetSessionTicketKeys, use Server.Serve with a TLS Listener
+	// instead.
+	TLSConfig *tls.Config
+
+	// ReadTimeout is the maximum duration for reading the entire
+	// request, including the body. A zero or negative value means
+	// there will be no timeout.
+	//
+	// Because ReadTimeout does not let Handlers make per-request
+	// decisions on each request body's acceptable deadline or
+	// upload rate, most users will prefer to use
+	// ReadHeaderTimeout. It is valid to use them both.
+	ReadTimeout time.Duration
+
+	// ReadHeaderTimeout is the amount of time allowed to read
+	// request headers. The connection's read deadline is reset
+	// after reading the headers and the Handler can decide what
+	// is considered too slow for the body. If ReadHeaderTimeout
+	// is zero, the value of ReadTimeout is used. If both are
+	// zero, there is no timeout.
+	ReadHeaderTimeout time.Duration
+
+	// WriteTimeout is the maximum duration before timing out
+	// writes of the response. It is reset whenever a new
+	// request's header is read. Like ReadTimeout, it does not
+	// let Handlers make decisions on a per-request basis.
+	// A zero or negative value means there will be no timeout.
+	WriteTimeout time.Duration
+
+	// IdleTimeout is the maximum amount of time to wait for the
+	// next request when keep-alives are enabled. If IdleTimeout
+	// is zero, the value of ReadTimeout is used. If both are
+	// zero, there is no timeout.
+	IdleTimeout time.Duration
+
+	// MaxHeaderBytes controls the maximum number of bytes the
+	// server will read parsing the request header's keys and
+	// values, including the request line. It does not limit the
+	// size of the request body.
+	// If zero, DefaultMaxHeaderBytes is used.
+	MaxHeaderBytes int
+
+	// TLSNextProto optionally specifies a function to take over
+	// ownership of the provided TLS connection when an ALPN
+	// protocol upgrade has occurred. The map key is the protocol
+	// name negotiated. The Handler argument should be used to
+	// handle HTTP requests and will initialize the Request's TLS
+	// and RemoteAddr if not already set. The connection is
+	// automatically closed when the function returns.
+	// If TLSNextProto is not nil, HTTP/2 support is not enabled
+	// automatically.
+	TLSNextProto map[string]func(*Server, *tls.Conn, Handler)
+
+	// ConnState specifies an optional callback function that is
+	// called when a client connection changes state. See the
+	// ConnState type and associated constants for details.
+	ConnState func(net.Conn, ConnState)
+
+	// ErrorLog specifies an optional logger for errors accepting
+	// connections, unexpected behavior from handlers, and
+	// underlying FileSystem errors.
+	// If nil, logging is done via the log package's standard logger.
+	ErrorLog *log.Logger
+
+	// BaseContext optionally specifies a function that returns
+	// the base context for incoming requests on this server.
+	// The provided Listener is the specific Listener that's
+	// about to start accepting requests.
+	// If BaseContext is nil, the default is context.Background().
+	// If non-nil, it must return a non-nil context.
+	BaseContext func(net.Listener) context.Context
+
+	// ConnContext optionally specifies a function that modifies
+	// the context used for a new connection c. The provided ctx
+	// is derived from the base context and has a ServerContextKey
+	// value.
+	ConnContext func(ctx context.Context, c net.Conn) context.Context
+
+	inShutdown atomicBool // true when server is in shutdown
+
+	disableKeepAlives int32     // accessed atomically.
+	nextProtoOnce     sync.Once // guards setupHTTP2_* init
+	nextProtoErr      error     // result of http2.ConfigureServer if used
+
+	mu         sync.Mutex
+	listeners  map[*net.Listener]struct{}
+	activeConn map[*conn]struct{}
+	doneChan   chan struct{}
+	onShutdown []func()
+
+	listenerGroup sync.WaitGroup
+}
+
+func (s *Server) getDoneChan() <-chan struct{} {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.getDoneChanLocked()
+}
+
+func (s *Server) getDoneChanLocked() chan struct{} {
+	if s.doneChan == nil {
+		s.doneChan = make(chan struct{})
+	}
+	return s.doneChan
+}
+
+func (s *Server) closeDoneChanLocked() {
+	ch := s.getDoneChanLocked()
+	select {
+	case <-ch:
+		// Already closed. Don't close again.
+	default:
+		// Safe to close here. We're the only closer, guarded
+		// by s.mu.
+		close(ch)
+	}
+}
+
+// Close immediately closes all active net.Listeners and any
+// connections in state StateNew, StateActive, or StateIdle. For a
+// graceful shutdown, use Shutdown.
+//
+// Close does not attempt to close (and does not even know about)
+// any hijacked connections, such as WebSockets.
+//
+// Close returns any error returned from closing the Server's
+// underlying Listener(s).
+func (srv *Server) Close() error {
+	srv.inShutdown.setTrue()
+	srv.mu.Lock()
+	defer srv.mu.Unlock()
+	srv.closeDoneChanLocked()
+	err := srv.closeListenersLocked()
+
+	// Unlock srv.mu while waiting for listenerGroup.
+	// The group Add and Done calls are made with srv.mu held,
+	// to avoid adding a new listener in the window between
+	// us setting inShutdown above and waiting here.
+	srv.mu.Unlock()
+	srv.listenerGroup.Wait()
+	srv.mu.Lock()
+
+	for c := range srv.activeConn {
+		c.rwc.Close()
+		delete(srv.activeConn, c)
+	}
+	return err
+}
+
+// shutdownPollIntervalMax is the max polling interval when checking
+// quiescence during Server.Shutdown. Polling starts with a small
+// interval and backs off to the max.
+// Ideally we could find a solution that doesn't involve polling,
+// but which also doesn't have a high runtime cost (and doesn't
+// involve any contentious mutexes), but that is left as an
+// exercise for the reader.
+const shutdownPollIntervalMax = 500 * time.Millisecond
+
+// Shutdown gracefully shuts down the server without interrupting any
+// active connections. Shutdown works by first closing all open
+// listeners, then closing all idle connections, and then waiting
+// indefinitely for connections to return to idle and then shut down.
+// If the provided context expires before the shutdown is complete,
+// Shutdown returns the context's error, otherwise it returns any
+// error returned from closing the Server's underlying Listener(s).
+//
+// When Shutdown is called, Serve, ListenAndServe, and
+// ListenAndServeTLS immediately return ErrServerClosed. Make sure the
+// program doesn't exit and waits instead for Shutdown to return.
+//
+// Shutdown does not attempt to close nor wait for hijacked
+// connections such as WebSockets. The caller of Shutdown should
+// separately notify such long-lived connections of shutdown and wait
+// for them to close, if desired. See RegisterOnShutdown for a way to
+// register shutdown notification functions.
+//
+// Once Shutdown has been called on a server, it may not be reused;
+// future calls to methods such as Serve will return ErrServerClosed.
+func (srv *Server) Shutdown(ctx context.Context) error {
+	srv.inShutdown.setTrue()
+
+	srv.mu.Lock()
+	lnerr := srv.closeListenersLocked()
+	srv.closeDoneChanLocked()
+	for _, f := range srv.onShutdown {
+		go f()
+	}
+	srv.mu.Unlock()
+	srv.listenerGroup.Wait()
+
+	pollIntervalBase := time.Millisecond
+	nextPollInterval := func() time.Duration {
+		// Add 10% jitter.
+		interval := pollIntervalBase + time.Duration(rand.Intn(int(pollIntervalBase/10)))
+		// Double and clamp for next time.
+		pollIntervalBase *= 2
+		if pollIntervalBase > shutdownPollIntervalMax {
+			pollIntervalBase = shutdownPollIntervalMax
+		}
+		return interval
+	}
+
+	timer := time.NewTimer(nextPollInterval())
+	defer timer.Stop()
+	for {
+		if srv.closeIdleConns() {
+			return lnerr
+		}
+		select {
+		case <-ctx.Done():
+			return ctx.Err()
+		case <-timer.C:
+			timer.Reset(nextPollInterval())
+		}
+	}
+}
+
+// RegisterOnShutdown registers a function to call on Shutdown.
+// This can be used to gracefully shutdown connections that have
+// undergone ALPN protocol upgrade or that have been hijacked.
+// This function should start protocol-specific graceful shutdown,
+// but should not wait for shutdown to complete.
+func (srv *Server) RegisterOnShutdown(f func()) {
+	srv.mu.Lock()
+	srv.onShutdown = append(srv.onShutdown, f)
+	srv.mu.Unlock()
+}
+
+// closeIdleConns closes all idle connections and reports whether the
+// server is quiescent.
+func (s *Server) closeIdleConns() bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	quiescent := true
+	for c := range s.activeConn {
+		st, unixSec := c.getState()
+		// Issue 22682: treat StateNew connections as if
+		// they're idle if we haven't read the first request's
+		// header in over 5 seconds.
+		if st == StateNew && unixSec < time.Now().Unix()-5 {
+			st = StateIdle
+		}
+		if st != StateIdle || unixSec == 0 {
+			// Assume unixSec == 0 means it's a very new
+			// connection, without state set yet.
+			quiescent = false
+			continue
+		}
+		c.rwc.Close()
+		delete(s.activeConn, c)
+	}
+	return quiescent
+}
+
+func (s *Server) closeListenersLocked() error {
+	var err error
+	for ln := range s.listeners {
+		if cerr := (*ln).Close(); cerr != nil && err == nil {
+			err = cerr
+		}
+	}
+	return err
+}
+
+// A ConnState represents the state of a client connection to a server.
+// It's used by the optional Server.ConnState hook.
+type ConnState int
+
+const (
+	// StateNew represents a new connection that is expected to
+	// send a request immediately. Connections begin at this
+	// state and then transition to either StateActive or
+	// StateClosed.
+	StateNew ConnState = iota
+
+	// StateActive represents a connection that has read 1 or more
+	// bytes of a request. The Server.ConnState hook for
+	// StateActive fires before the request has entered a handler
+	// and doesn't fire again until the request has been
+	// handled. After the request is handled, the state
+	// transitions to StateClosed, StateHijacked, or StateIdle.
+	// For HTTP/2, StateActive fires on the transition from zero
+	// to one active request, and only transitions away once all
+	// active requests are complete. That means that ConnState
+	// cannot be used to do per-request work; ConnState only notes
+	// the overall state of the connection.
+	StateActive
+
+	// StateIdle represents a connection that has finished
+	// handling a request and is in the keep-alive state, waiting
+	// for a new request. Connections transition from StateIdle
+	// to either StateActive or StateClosed.
+	StateIdle
+
+	// StateHijacked represents a hijacked connection.
+	// This is a terminal state. It does not transition to StateClosed.
+	StateHijacked
+
+	// StateClosed represents a closed connection.
+	// This is a terminal state. Hijacked connections do not
+	// transition to StateClosed.
+	StateClosed
+)
+
+var stateName = map[ConnState]string{
+	StateNew:      "new",
+	StateActive:   "active",
+	StateIdle:     "idle",
+	StateHijacked: "hijacked",
+	StateClosed:   "closed",
+}
+
+func (c ConnState) String() string {
+	return stateName[c]
+}
+
+// serverHandler delegates to either the server's Handler or
+// DefaultServeMux and also handles "OPTIONS *" requests.
+type serverHandler struct {
+	srv *Server
+}
+
+func (sh serverHandler) ServeHTTP(rw ResponseWriter, req *Request) {
+	handler := sh.srv.Handler
+	if handler == nil {
+		handler = DefaultServeMux
+	}
+	if req.RequestURI == "*" && req.Method == "OPTIONS" {
+		handler = globalOptionsHandler{}
+	}
+
+	if req.URL != nil && strings.Contains(req.URL.RawQuery, ";") {
+		var allowQuerySemicolonsInUse int32
+		req = req.WithContext(context.WithValue(req.Context(), silenceSemWarnContextKey, func() {
+			atomic.StoreInt32(&allowQuerySemicolonsInUse, 1)
+		}))
+		defer func() {
+			if atomic.LoadInt32(&allowQuerySemicolonsInUse) == 0 {
+				sh.srv.logf("http: URL query contains semicolon, which is no longer a supported separator; parts of the query may be stripped when parsed; see golang.org/issue/25192")
+			}
+		}()
+	}
+
+	handler.ServeHTTP(rw, req)
+}
+
+var silenceSemWarnContextKey = &contextKey{"silence-semicolons"}
+
+// AllowQuerySemicolons returns a handler that serves requests by converting any
+// unescaped semicolons in the URL query to ampersands, and invoking the handler h.
+//
+// This restores the pre-Go 1.17 behavior of splitting query parameters on both
+// semicolons and ampersands. (See golang.org/issue/25192). Note that this
+// behavior doesn't match that of many proxies, and the mismatch can lead to
+// security issues.
+//
+// AllowQuerySemicolons should be invoked before Request.ParseForm is called.
+func AllowQuerySemicolons(h Handler) Handler {
+	return HandlerFunc(func(w ResponseWriter, r *Request) {
+		if silenceSemicolonsWarning, ok := r.Context().Value(silenceSemWarnContextKey).(func()); ok {
+			silenceSemicolonsWarning()
+		}
+		if strings.Contains(r.URL.RawQuery, ";") {
+			r2 := new(Request)
+			*r2 = *r
+			r2.URL = new(url.URL)
+			*r2.URL = *r.URL
+			r2.URL.RawQuery = strings.ReplaceAll(r.URL.RawQuery, ";", "&")
+			h.ServeHTTP(w, r2)
+		} else {
+			h.ServeHTTP(w, r)
+		}
+	})
+}
+
+// ListenAndServe listens on the TCP network address srv.Addr and then
+// calls Serve to handle requests on incoming connections.
+// Accepted connections are configured to enable TCP keep-alives.
+//
+// If srv.Addr is blank, ":http" is used.
+//
+// ListenAndServe always returns a non-nil error. After Shutdown or Close,
+// the returned error is ErrServerClosed.
+func (srv *Server) ListenAndServe() error {
+	if srv.shuttingDown() {
+		return ErrServerClosed
+	}
+	addr := srv.Addr
+	if addr == "" {
+		addr = ":http"
+	}
+	ln, err := net.Listen("tcp", addr)
+	if err != nil {
+		return err
+	}
+	return srv.Serve(ln)
+}
+
+var testHookServerServe func(*Server, net.Listener) // used if non-nil
+
+// shouldDoServeHTTP2 reports whether Server.Serve should configure
+// automatic HTTP/2. (which sets up the srv.TLSNextProto map)
+func (srv *Server) shouldConfigureHTTP2ForServe() bool {
+	if srv.TLSConfig == nil {
+		// Compatibility with Go 1.6:
+		// If there's no TLSConfig, it's possible that the user just
+		// didn't set it on the http.Server, but did pass it to
+		// tls.NewListener and passed that listener to Serve.
+		// So we should configure HTTP/2 (to set up srv.TLSNextProto)
+		// in case the listener returns an "h2" *tls.Conn.
+		return true
+	}
+	// The user specified a TLSConfig on their http.Server.
+	// In this, case, only configure HTTP/2 if their tls.Config
+	// explicitly mentions "h2". Otherwise http2.ConfigureServer
+	// would modify the tls.Config to add it, but they probably already
+	// passed this tls.Config to tls.NewListener. And if they did,
+	// it's too late anyway to fix it. It would only be potentially racy.
+	// See Issue 15908.
+	return strSliceContains(srv.TLSConfig.NextProtos, http2NextProtoTLS)
+}
+
+// ErrServerClosed is returned by the Server's Serve, ServeTLS, ListenAndServe,
+// and ListenAndServeTLS methods after a call to Shutdown or Close.
+var ErrServerClosed = errors.New("http: Server closed")
+
+// Serve accepts incoming connections on the Listener l, creating a
+// new service goroutine for each. The service goroutines read requests and
+// then call srv.Handler to reply to them.
+//
+// HTTP/2 support is only enabled if the Listener returns *tls.Conn
+// connections and they were configured with "h2" in the TLS
+// Config.NextProtos.
+//
+// Serve always returns a non-nil error and closes l.
+// After Shutdown or Close, the returned error is ErrServerClosed.
+func (srv *Server) Serve(l net.Listener) error {
+	if fn := testHookServerServe; fn != nil {
+		fn(srv, l) // call hook with unwrapped listener
+	}
+
+	origListener := l
+	l = &onceCloseListener{Listener: l}
+	defer l.Close()
+
+	if err := srv.setupHTTP2_Serve(); err != nil {
+		return err
+	}
+
+	if !srv.trackListener(&l, true) {
+		return ErrServerClosed
+	}
+	defer srv.trackListener(&l, false)
+
+	baseCtx := context.Background()
+	if srv.BaseContext != nil {
+		baseCtx = srv.BaseContext(origListener)
+		if baseCtx == nil {
+			panic("BaseContext returned a nil context")
+		}
+	}
+
+	var tempDelay time.Duration // how long to sleep on accept failure
+
+	ctx := context.WithValue(baseCtx, ServerContextKey, srv)
+	for {
+		rw, err := l.Accept()
+		if err != nil {
+			select {
+			case <-srv.getDoneChan():
+				return ErrServerClosed
+			default:
+			}
+			if ne, ok := err.(net.Error); ok && ne.Temporary() {
+				if tempDelay == 0 {
+					tempDelay = 5 * time.Millisecond
+				} else {
+					tempDelay *= 2
+				}
+				if max := 1 * time.Second; tempDelay > max {
+					tempDelay = max
+				}
+				srv.logf("http: Accept error: %v; retrying in %v", err, tempDelay)
+				time.Sleep(tempDelay)
+				continue
+			}
+			return err
+		}
+		connCtx := ctx
+		if cc := srv.ConnContext; cc != nil {
+			connCtx = cc(connCtx, rw)
+			if connCtx == nil {
+				panic("ConnContext returned nil")
+			}
+		}
+		tempDelay = 0
+		c := srv.newConn(rw)
+		c.setState(c.rwc, StateNew, runHooks) // before Serve can return
+		go c.serve(connCtx)
+	}
+}
+
+// ServeTLS accepts incoming connections on the Listener l, creating a
+// new service goroutine for each. The service goroutines perform TLS
+// setup and then read requests, calling srv.Handler to reply to them.
+//
+// Files containing a certificate and matching private key for the
+// server must be provided if neither the Server's
+// TLSConfig.Certificates nor TLSConfig.GetCertificate are populated.
+// If the certificate is signed by a certificate authority, the
+// certFile should be the concatenation of the server's certificate,
+// any intermediates, and the CA's certificate.
+//
+// ServeTLS always returns a non-nil error. After Shutdown or Close, the
+// returned error is ErrServerClosed.
+func (srv *Server) ServeTLS(l net.Listener, certFile, keyFile string) error {
+	// Setup HTTP/2 before srv.Serve, to initialize srv.TLSConfig
+	// before we clone it and create the TLS Listener.
+	if err := srv.setupHTTP2_ServeTLS(); err != nil {
+		return err
+	}
+
+	config := cloneTLSConfig(srv.TLSConfig)
+	if !strSliceContains(config.NextProtos, "http/1.1") {
+		config.NextProtos = append(config.NextProtos, "http/1.1")
+	}
+
+	configHasCert := len(config.Certificates) > 0 || config.GetCertificate != nil
+	if !configHasCert || certFile != "" || keyFile != "" {
+		var err error
+		config.Certificates = make([]tls.Certificate, 1)
+		config.Certificates[0], err = tls.LoadX509KeyPair(certFile, keyFile)
+		if err != nil {
+			return err
+		}
+	}
+
+	tlsListener := tls.NewListener(l, config)
+	return srv.Serve(tlsListener)
+}
+
+// trackListener adds or removes a net.Listener to the set of tracked
+// listeners.
+//
+// We store a pointer to interface in the map set, in case the
+// net.Listener is not comparable. This is safe because we only call
+// trackListener via Serve and can track+defer untrack the same
+// pointer to local variable there. We never need to compare a
+// Listener from another caller.
+//
+// It reports whether the server is still up (not Shutdown or Closed).
+func (s *Server) trackListener(ln *net.Listener, add bool) bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if s.listeners == nil {
+		s.listeners = make(map[*net.Listener]struct{})
+	}
+	if add {
+		if s.shuttingDown() {
+			return false
+		}
+		s.listeners[ln] = struct{}{}
+		s.listenerGroup.Add(1)
+	} else {
+		delete(s.listeners, ln)
+		s.listenerGroup.Done()
+	}
+	return true
+}
+
+func (s *Server) trackConn(c *conn, add bool) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if s.activeConn == nil {
+		s.activeConn = make(map[*conn]struct{})
+	}
+	if add {
+		s.activeConn[c] = struct{}{}
+	} else {
+		delete(s.activeConn, c)
+	}
+}
+
+func (s *Server) idleTimeout() time.Duration {
+	if s.IdleTimeout != 0 {
+		return s.IdleTimeout
+	}
+	return s.ReadTimeout
+}
+
+func (s *Server) readHeaderTimeout() time.Duration {
+	if s.ReadHeaderTimeout != 0 {
+		return s.ReadHeaderTimeout
+	}
+	return s.ReadTimeout
+}
+
+func (s *Server) doKeepAlives() bool {
+	return atomic.LoadInt32(&s.disableKeepAlives) == 0 && !s.shuttingDown()
+}
+
+func (s *Server) shuttingDown() bool {
+	return s.inShutdown.isSet()
+}
+
+// SetKeepAlivesEnabled controls whether HTTP keep-alives are enabled.
+// By default, keep-alives are always enabled. Only very
+// resource-constrained environments or servers in the process of
+// shutting down should disable them.
+func (srv *Server) SetKeepAlivesEnabled(v bool) {
+	if v {
+		atomic.StoreInt32(&srv.disableKeepAlives, 0)
+		return
+	}
+	atomic.StoreInt32(&srv.disableKeepAlives, 1)
+
+	// Close idle HTTP/1 conns:
+	srv.closeIdleConns()
+
+	// TODO: Issue 26303: close HTTP/2 conns as soon as they become idle.
+}
+
+func (s *Server) logf(format string, args ...any) {
+	if s.ErrorLog != nil {
+		s.ErrorLog.Printf(format, args...)
+	} else {
+		log.Printf(format, args...)
+	}
+}
+
+// logf prints to the ErrorLog of the *Server associated with request r
+// via ServerContextKey. If there's no associated server, or if ErrorLog
+// is nil, logging is done via the log package's standard logger.
+func logf(r *Request, format string, args ...any) {
+	s, _ := r.Context().Value(ServerContextKey).(*Server)
+	if s != nil && s.ErrorLog != nil {
+		s.ErrorLog.Printf(format, args...)
+	} else {
+		log.Printf(format, args...)
+	}
+}
+
+// ListenAndServe listens on the TCP network address addr and then calls
+// Serve with handler to handle requests on incoming connections.
+// Accepted connections are configured to enable TCP keep-alives.
+//
+// The handler is typically nil, in which case the DefaultServeMux is used.
+//
+// ListenAndServe always returns a non-nil error.
+func ListenAndServe(addr string, handler Handler) error {
+	server := &Server{Addr: addr, Handler: handler}
+	return server.ListenAndServe()
+}
+
+// ListenAndServeTLS acts identically to ListenAndServe, except that it
+// expects HTTPS connections. Additionally, files containing a certificate and
+// matching private key for the server must be provided. If the certificate
+// is signed by a certificate authority, the certFile should be the concatenation
+// of the server's certificate, any intermediates, and the CA's certificate.
+func ListenAndServeTLS(addr, certFile, keyFile string, handler Handler) error {
+	server := &Server{Addr: addr, Handler: handler}
+	return server.ListenAndServeTLS(certFile, keyFile)
+}
+
+// ListenAndServeTLS listens on the TCP network address srv.Addr and
+// then calls ServeTLS to handle requests on incoming TLS connections.
+// Accepted connections are configured to enable TCP keep-alives.
+//
+// Filenames containing a certificate and matching private key for the
+// server must be provided if neither the Server's TLSConfig.Certificates
+// nor TLSConfig.GetCertificate are populated. If the certificate is
+// signed by a certificate authority, the certFile should be the
+// concatenation of the server's certificate, any intermediates, and
+// the CA's certificate.
+//
+// If srv.Addr is blank, ":https" is used.
+//
+// ListenAndServeTLS always returns a non-nil error. After Shutdown or
+// Close, the returned error is ErrServerClosed.
+func (srv *Server) ListenAndServeTLS(certFile, keyFile string) error {
+	if srv.shuttingDown() {
+		return ErrServerClosed
+	}
+	addr := srv.Addr
+	if addr == "" {
+		addr = ":https"
+	}
+
+	ln, err := net.Listen("tcp", addr)
+	if err != nil {
+		return err
+	}
+
+	defer ln.Close()
+
+	return srv.ServeTLS(ln, certFile, keyFile)
+}
+
+// setupHTTP2_ServeTLS conditionally configures HTTP/2 on
+// srv and reports whether there was an error setting it up. If it is
+// not configured for policy reasons, nil is returned.
+func (srv *Server) setupHTTP2_ServeTLS() error {
+	srv.nextProtoOnce.Do(srv.onceSetNextProtoDefaults)
+	return srv.nextProtoErr
+}
+
+// setupHTTP2_Serve is called from (*Server).Serve and conditionally
+// configures HTTP/2 on srv using a more conservative policy than
+// setupHTTP2_ServeTLS because Serve is called after tls.Listen,
+// and may be called concurrently. See shouldConfigureHTTP2ForServe.
+//
+// The tests named TestTransportAutomaticHTTP2* and
+// TestConcurrentServerServe in server_test.go demonstrate some
+// of the supported use cases and motivations.
+func (srv *Server) setupHTTP2_Serve() error {
+	srv.nextProtoOnce.Do(srv.onceSetNextProtoDefaults_Serve)
+	return srv.nextProtoErr
+}
+
+func (srv *Server) onceSetNextProtoDefaults_Serve() {
+	if srv.shouldConfigureHTTP2ForServe() {
+		srv.onceSetNextProtoDefaults()
+	}
+}
+
+// onceSetNextProtoDefaults configures HTTP/2, if the user hasn't
+// configured otherwise. (by setting srv.TLSNextProto non-nil)
+// It must only be called via srv.nextProtoOnce (use srv.setupHTTP2_*).
+func (srv *Server) onceSetNextProtoDefaults() {
+	if omitBundledHTTP2 || godebug.Get("http2server") == "0" {
+		return
+	}
+	// Enable HTTP/2 by default if the user hasn't otherwise
+	// configured their TLSNextProto map.
+	if srv.TLSNextProto == nil {
+		conf := &http2Server{
+			NewWriteScheduler: func() http2WriteScheduler { return http2NewPriorityWriteScheduler(nil) },
+		}
+		srv.nextProtoErr = http2ConfigureServer(srv, conf)
+	}
+}
+
+// TimeoutHandler returns a Handler that runs h with the given time limit.
+//
+// The new Handler calls h.ServeHTTP to handle each request, but if a
+// call runs for longer than its time limit, the handler responds with
+// a 503 Service Unavailable error and the given message in its body.
+// (If msg is empty, a suitable default message will be sent.)
+// After such a timeout, writes by h to its ResponseWriter will return
+// ErrHandlerTimeout.
+//
+// TimeoutHandler supports the Pusher interface but does not support
+// the Hijacker or Flusher interfaces.
+func TimeoutHandler(h Handler, dt time.Duration, msg string) Handler {
+	return &timeoutHandler{
+		handler: h,
+		body:    msg,
+		dt:      dt,
+	}
+}
+
+// ErrHandlerTimeout is returned on ResponseWriter Write calls
+// in handlers which have timed out.
+var ErrHandlerTimeout = errors.New("http: Handler timeout")
+
+type timeoutHandler struct {
+	handler Handler
+	body    string
+	dt      time.Duration
+
+	// When set, no context will be created and this context will
+	// be used instead.
+	testContext context.Context
+}
+
+func (h *timeoutHandler) errorBody() string {
+	if h.body != "" {
+		return h.body
+	}
+	return "<html><head><title>Timeout</title></head><body><h1>Timeout</h1></body></html>"
+}
+
+func (h *timeoutHandler) ServeHTTP(w ResponseWriter, r *Request) {
+	ctx := h.testContext
+	if ctx == nil {
+		var cancelCtx context.CancelFunc
+		ctx, cancelCtx = context.WithTimeout(r.Context(), h.dt)
+		defer cancelCtx()
+	}
+	r = r.WithContext(ctx)
+	done := make(chan struct{})
+	tw := &timeoutWriter{
+		w:   w,
+		h:   make(Header),
+		req: r,
+	}
+	panicChan := make(chan any, 1)
+	go func() {
+		defer func() {
+			if p := recover(); p != nil {
+				panicChan <- p
+			}
+		}()
+		h.handler.ServeHTTP(tw, r)
+		close(done)
+	}()
+	select {
+	case p := <-panicChan:
+		panic(p)
+	case <-done:
+		tw.mu.Lock()
+		defer tw.mu.Unlock()
+		dst := w.Header()
+		for k, vv := range tw.h {
+			dst[k] = vv
+		}
+		if !tw.wroteHeader {
+			tw.code = StatusOK
+		}
+		w.WriteHeader(tw.code)
+		w.Write(tw.wbuf.Bytes())
+	case <-ctx.Done():
+		tw.mu.Lock()
+		defer tw.mu.Unlock()
+		switch err := ctx.Err(); err {
+		case context.DeadlineExceeded:
+			w.WriteHeader(StatusServiceUnavailable)
+			io.WriteString(w, h.errorBody())
+			tw.err = ErrHandlerTimeout
+		default:
+			w.WriteHeader(StatusServiceUnavailable)
+			tw.err = err
+		}
+	}
+}
+
+type timeoutWriter struct {
+	w    ResponseWriter
+	h    Header
+	wbuf bytes.Buffer
+	req  *Request
+
+	mu          sync.Mutex
+	err         error
+	wroteHeader bool
+	code        int
+}
+
+var _ Pusher = (*timeoutWriter)(nil)
+
+// Push implements the Pusher interface.
+func (tw *timeoutWriter) Push(target string, opts *PushOptions) error {
+	if pusher, ok := tw.w.(Pusher); ok {
+		return pusher.Push(target, opts)
+	}
+	return ErrNotSupported
+}
+
+func (tw *timeoutWriter) Header() Header { return tw.h }
+
+func (tw *timeoutWriter) Write(p []byte) (int, error) {
+	tw.mu.Lock()
+	defer tw.mu.Unlock()
+	if tw.err != nil {
+		return 0, tw.err
+	}
+	if !tw.wroteHeader {
+		tw.writeHeaderLocked(StatusOK)
+	}
+	return tw.wbuf.Write(p)
+}
+
+func (tw *timeoutWriter) writeHeaderLocked(code int) {
+	checkWriteHeaderCode(code)
+
+	switch {
+	case tw.err != nil:
+		return
+	case tw.wroteHeader:
+		if tw.req != nil {
+			caller := relevantCaller()
+			logf(tw.req, "http: superfluous response.WriteHeader call from %s (%s:%d)", caller.Function, path.Base(caller.File), caller.Line)
+		}
+	default:
+		tw.wroteHeader = true
+		tw.code = code
+	}
+}
+
+func (tw *timeoutWriter) WriteHeader(code int) {
+	tw.mu.Lock()
+	defer tw.mu.Unlock()
+	tw.writeHeaderLocked(code)
+}
+
+// onceCloseListener wraps a net.Listener, protecting it from
+// multiple Close calls.
+type onceCloseListener struct {
+	net.Listener
+	once     sync.Once
+	closeErr error
+}
+
+func (oc *onceCloseListener) Close() error {
+	oc.once.Do(oc.close)
+	return oc.closeErr
+}
+
+func (oc *onceCloseListener) close() { oc.closeErr = oc.Listener.Close() }
+
+// globalOptionsHandler responds to "OPTIONS *" requests.
+type globalOptionsHandler struct{}
+
+func (globalOptionsHandler) ServeHTTP(w ResponseWriter, r *Request) {
+	w.Header().Set("Content-Length", "0")
+	if r.ContentLength != 0 {
+		// Read up to 4KB of OPTIONS body (as mentioned in the
+		// spec as being reserved for future use), but anything
+		// over that is considered a waste of server resources
+		// (or an attack) and we abort and close the connection,
+		// courtesy of MaxBytesReader's EOF behavior.
+		mb := MaxBytesReader(w, r.Body, 4<<10)
+		io.Copy(io.Discard, mb)
+	}
+}
+
+// initALPNRequest is an HTTP handler that initializes certain
+// uninitialized fields in its *Request. Such partially-initialized
+// Requests come from ALPN protocol handlers.
+type initALPNRequest struct {
+	ctx context.Context
+	c   *tls.Conn
+	h   serverHandler
+}
+
+// BaseContext is an exported but unadvertised http.Handler method
+// recognized by x/net/http2 to pass down a context; the TLSNextProto
+// API predates context support so we shoehorn through the only
+// interface we have available.
+func (h initALPNRequest) BaseContext() context.Context { return h.ctx }
+
+func (h initALPNRequest) ServeHTTP(rw ResponseWriter, req *Request) {
+	if req.TLS == nil {
+		req.TLS = &tls.ConnectionState{}
+		*req.TLS = h.c.ConnectionState()
+	}
+	if req.Body == nil {
+		req.Body = NoBody
+	}
+	if req.RemoteAddr == "" {
+		req.RemoteAddr = h.c.RemoteAddr().String()
+	}
+	h.h.ServeHTTP(rw, req)
+}
+
+// loggingConn is used for debugging.
+type loggingConn struct {
+	name string
+	net.Conn
+}
+
+var (
+	uniqNameMu   sync.Mutex
+	uniqNameNext = make(map[string]int)
+)
+
+func newLoggingConn(baseName string, c net.Conn) net.Conn {
+	uniqNameMu.Lock()
+	defer uniqNameMu.Unlock()
+	uniqNameNext[baseName]++
+	return &loggingConn{
+		name: fmt.Sprintf("%s-%d", baseName, uniqNameNext[baseName]),
+		Conn: c,
+	}
+}
+
+func (c *loggingConn) Write(p []byte) (n int, err error) {
+	log.Printf("%s.Write(%d) = ....", c.name, len(p))
+	n, err = c.Conn.Write(p)
+	log.Printf("%s.Write(%d) = %d, %v", c.name, len(p), n, err)
+	return
+}
+
+func (c *loggingConn) Read(p []byte) (n int, err error) {
+	log.Printf("%s.Read(%d) = ....", c.name, len(p))
+	n, err = c.Conn.Read(p)
+	log.Printf("%s.Read(%d) = %d, %v", c.name, len(p), n, err)
+	return
+}
+
+func (c *loggingConn) Close() (err error) {
+	log.Printf("%s.Close() = ...", c.name)
+	err = c.Conn.Close()
+	log.Printf("%s.Close() = %v", c.name, err)
+	return
+}
+
+// checkConnErrorWriter writes to c.rwc and records any write errors to c.werr.
+// It only contains one field (and a pointer field at that), so it
+// fits in an interface value without an extra allocation.
+type checkConnErrorWriter struct {
+	c *conn
+}
+
+func (w checkConnErrorWriter) Write(p []byte) (n int, err error) {
+	n, err = w.c.rwc.Write(p)
+	if err != nil && w.c.werr == nil {
+		w.c.werr = err
+		w.c.cancelCtx()
+	}
+	return
+}
+
+func numLeadingCRorLF(v []byte) (n int) {
+	for _, b := range v {
+		if b == '\r' || b == '\n' {
+			n++
+			continue
+		}
+		break
+	}
+	return
+
+}
+
+func strSliceContains(ss []string, s string) bool {
+	for _, v := range ss {
+		if v == s {
+			return true
+		}
+	}
+	return false
+}
+
+// tlsRecordHeaderLooksLikeHTTP reports whether a TLS record header
+// looks like it might've been a misdirected plaintext HTTP request.
+func tlsRecordHeaderLooksLikeHTTP(hdr [5]byte) bool {
+	switch string(hdr[:]) {
+	case "GET /", "HEAD ", "POST ", "PUT /", "OPTIO":
+		return true
+	}
+	return false
+}
+
+// MaxBytesHandler returns a Handler that runs h with its ResponseWriter and Request.Body wrapped by a MaxBytesReader.
+func MaxBytesHandler(h Handler, n int64) Handler {
+	return HandlerFunc(func(w ResponseWriter, r *Request) {
+		r2 := *r
+		r2.Body = MaxBytesReader(w, r.Body, n)
+		h.ServeHTTP(w, &r2)
+	})
+}
diff --git a/contrib/go/_std_1.19/src/net/http/sniff.go b/contrib/go/_std_1.19/src/net/http/sniff.go
new file mode 100644
index 0000000000..ac18ab979d
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/http/sniff.go
@@ -0,0 +1,304 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package http
+
+import (
+	"bytes"
+	"encoding/binary"
+)
+
+// The algorithm uses at most sniffLen bytes to make its decision.
+const sniffLen = 512
+
+// DetectContentType implements the algorithm described
+// at https://mimesniff.spec.whatwg.org/ to determine the
+// Content-Type of the given data. It considers at most the
+// first 512 bytes of data. DetectContentType always returns
+// a valid MIME type: if it cannot determine a more specific one, it
+// returns "application/octet-stream".
+func DetectContentType(data []byte) string {
+	if len(data) > sniffLen {
+		data = data[:sniffLen]
+	}
+
+	// Index of the first non-whitespace byte in data.
+	firstNonWS := 0
+	for ; firstNonWS < len(data) && isWS(data[firstNonWS]); firstNonWS++ {
+	}
+
+	for _, sig := range sniffSignatures {
+		if ct := sig.match(data, firstNonWS); ct != "" {
+			return ct
+		}
+	}
+
+	return "application/octet-stream" // fallback
+}
+
+// isWS reports whether the provided byte is a whitespace byte (0xWS)
+// as defined in https://mimesniff.spec.whatwg.org/#terminology.
+func isWS(b byte) bool {
+	switch b {
+	case '\t', '\n', '\x0c', '\r', ' ':
+		return true
+	}
+	return false
+}
+
+// isTT reports whether the provided byte is a tag-terminating byte (0xTT)
+// as defined in https://mimesniff.spec.whatwg.org/#terminology.
+func isTT(b byte) bool {
+	switch b {
+	case ' ', '>':
+		return true
+	}
+	return false
+}
+
+type sniffSig interface {
+	// match returns the MIME type of the data, or "" if unknown.
+	match(data []byte, firstNonWS int) string
+}
+
+// Data matching the table in section 6.
+var sniffSignatures = []sniffSig{
+	htmlSig("<!DOCTYPE HTML"),
+	htmlSig("<HTML"),
+	htmlSig("<HEAD"),
+	htmlSig("<SCRIPT"),
+	htmlSig("<IFRAME"),
+	htmlSig("<H1"),
+	htmlSig("<DIV"),
+	htmlSig("<FONT"),
+	htmlSig("<TABLE"),
+	htmlSig("<A"),
+	htmlSig("<STYLE"),
+	htmlSig("<TITLE"),
+	htmlSig("<B"),
+	htmlSig("<BODY"),
+	htmlSig("<BR"),
+	htmlSig("<P"),
+	htmlSig("<!--"),
+	&maskedSig{
+		mask:   []byte("\xFF\xFF\xFF\xFF\xFF"),
+		pat:    []byte("<?xml"),
+		skipWS: true,
+		ct:     "text/xml; charset=utf-8"},
+	&exactSig{[]byte("%PDF-"), "application/pdf"},
+	&exactSig{[]byte("%!PS-Adobe-"), "application/postscript"},
+
+	// UTF BOMs.
+	&maskedSig{
+		mask: []byte("\xFF\xFF\x00\x00"),
+		pat:  []byte("\xFE\xFF\x00\x00"),
+		ct:   "text/plain; charset=utf-16be",
+	},
+	&maskedSig{
+		mask: []byte("\xFF\xFF\x00\x00"),
+		pat:  []byte("\xFF\xFE\x00\x00"),
+		ct:   "text/plain; charset=utf-16le",
+	},
+	&maskedSig{
+		mask: []byte("\xFF\xFF\xFF\x00"),
+		pat:  []byte("\xEF\xBB\xBF\x00"),
+		ct:   "text/plain; charset=utf-8",
+	},
+
+	// Image types
+	// For posterity, we originally returned "image/vnd.microsoft.icon" from
+	// https://tools.ietf.org/html/draft-ietf-websec-mime-sniff-03#section-7
+	// https://codereview.appspot.com/4746042
+	// but that has since been replaced with "image/x-icon" in Section 6.2
+	// of https://mimesniff.spec.whatwg.org/#matching-an-image-type-pattern
+	&exactSig{[]byte("\x00\x00\x01\x00"), "image/x-icon"},
+	&exactSig{[]byte("\x00\x00\x02\x00"), "image/x-icon"},
+	&exactSig{[]byte("BM"), "image/bmp"},
+	&exactSig{[]byte("GIF87a"), "image/gif"},
+	&exactSig{[]byte("GIF89a"), "image/gif"},
+	&maskedSig{
+		mask: []byte("\xFF\xFF\xFF\xFF\x00\x00\x00\x00\xFF\xFF\xFF\xFF\xFF\xFF"),
+		pat:  []byte("RIFF\x00\x00\x00\x00WEBPVP"),
+		ct:   "image/webp",
+	},
+	&exactSig{[]byte("\x89PNG\x0D\x0A\x1A\x0A"), "image/png"},
+	&exactSig{[]byte("\xFF\xD8\xFF"), "image/jpeg"},
+
+	// Audio and Video types
+	// Enforce the pattern match ordering as prescribed in
+	// https://mimesniff.spec.whatwg.org/#matching-an-audio-or-video-type-pattern
+	&maskedSig{
+		mask: []byte("\xFF\xFF\xFF\xFF\x00\x00\x00\x00\xFF\xFF\xFF\xFF"),
+		pat:  []byte("FORM\x00\x00\x00\x00AIFF"),
+		ct:   "audio/aiff",
+	},
+	&maskedSig{
+		mask: []byte("\xFF\xFF\xFF"),
+		pat:  []byte("ID3"),
+		ct:   "audio/mpeg",
+	},
+	&maskedSig{
+		mask: []byte("\xFF\xFF\xFF\xFF\xFF"),
+		pat:  []byte("OggS\x00"),
+		ct:   "application/ogg",
+	},
+	&maskedSig{
+		mask: []byte("\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF"),
+		pat:  []byte("MThd\x00\x00\x00\x06"),
+		ct:   "audio/midi",
+	},
+	&maskedSig{
+		mask: []byte("\xFF\xFF\xFF\xFF\x00\x00\x00\x00\xFF\xFF\xFF\xFF"),
+		pat:  []byte("RIFF\x00\x00\x00\x00AVI "),
+		ct:   "video/avi",
+	},
+	&maskedSig{
+		mask: []byte("\xFF\xFF\xFF\xFF\x00\x00\x00\x00\xFF\xFF\xFF\xFF"),
+		pat:  []byte("RIFF\x00\x00\x00\x00WAVE"),
+		ct:   "audio/wave",
+	},
+	// 6.2.0.2. video/mp4
+	mp4Sig{},
+	// 6.2.0.3. video/webm
+	&exactSig{[]byte("\x1A\x45\xDF\xA3"), "video/webm"},
+
+	// Font types
+	&maskedSig{
+		// 34 NULL bytes followed by the string "LP"
+		pat: []byte("\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00LP"),
+		// 34 NULL bytes followed by \xF\xF
+		mask: []byte("\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xFF\xFF"),
+		ct:   "application/vnd.ms-fontobject",
+	},
+	&exactSig{[]byte("\x00\x01\x00\x00"), "font/ttf"},
+	&exactSig{[]byte("OTTO"), "font/otf"},
+	&exactSig{[]byte("ttcf"), "font/collection"},
+	&exactSig{[]byte("wOFF"), "font/woff"},
+	&exactSig{[]byte("wOF2"), "font/woff2"},
+
+	// Archive types
+	&exactSig{[]byte("\x1F\x8B\x08"), "application/x-gzip"},
+	&exactSig{[]byte("PK\x03\x04"), "application/zip"},
+	// RAR's signatures are incorrectly defined by the MIME spec as per
+	//    https://github.com/whatwg/mimesniff/issues/63
+	// However, RAR Labs correctly defines it at:
+	//    https://www.rarlab.com/technote.htm#rarsign
+	// so we use the definition from RAR Labs.
+	// TODO: do whatever the spec ends up doing.
+	&exactSig{[]byte("Rar!\x1A\x07\x00"), "application/x-rar-compressed"},     // RAR v1.5-v4.0
+	&exactSig{[]byte("Rar!\x1A\x07\x01\x00"), "application/x-rar-compressed"}, // RAR v5+
+
+	&exactSig{[]byte("\x00\x61\x73\x6D"), "application/wasm"},
+
+	textSig{}, // should be last
+}
+
+type exactSig struct {
+	sig []byte
+	ct  string
+}
+
+func (e *exactSig) match(data []byte, firstNonWS int) string {
+	if bytes.HasPrefix(data, e.sig) {
+		return e.ct
+	}
+	return ""
+}
+
+type maskedSig struct {
+	mask, pat []byte
+	skipWS    bool
+	ct        string
+}
+
+func (m *maskedSig) match(data []byte, firstNonWS int) string {
+	// pattern matching algorithm section 6
+	// https://mimesniff.spec.whatwg.org/#pattern-matching-algorithm
+
+	if m.skipWS {
+		data = data[firstNonWS:]
+	}
+	if len(m.pat) != len(m.mask) {
+		return ""
+	}
+	if len(data) < len(m.pat) {
+		return ""
+	}
+	for i, pb := range m.pat {
+		maskedData := data[i] & m.mask[i]
+		if maskedData != pb {
+			return ""
+		}
+	}
+	return m.ct
+}
+
+type htmlSig []byte
+
+func (h htmlSig) match(data []byte, firstNonWS int) string {
+	data = data[firstNonWS:]
+	if len(data) < len(h)+1 {
+		return ""
+	}
+	for i, b := range h {
+		db := data[i]
+		if 'A' <= b && b <= 'Z' {
+			db &= 0xDF
+		}
+		if b != db {
+			return ""
+		}
+	}
+	// Next byte must be a tag-terminating byte(0xTT).
+	if !isTT(data[len(h)]) {
+		return ""
+	}
+	return "text/html; charset=utf-8"
+}
+
+var mp4ftype = []byte("ftyp")
+var mp4 = []byte("mp4")
+
+type mp4Sig struct{}
+
+func (mp4Sig) match(data []byte, firstNonWS int) string {
+	// https://mimesniff.spec.whatwg.org/#signature-for-mp4
+	// c.f. section 6.2.1
+	if len(data) < 12 {
+		return ""
+	}
+	boxSize := int(binary.BigEndian.Uint32(data[:4]))
+	if len(data) < boxSize || boxSize%4 != 0 {
+		return ""
+	}
+	if !bytes.Equal(data[4:8], mp4ftype) {
+		return ""
+	}
+	for st := 8; st < boxSize; st += 4 {
+		if st == 12 {
+			// Ignores the four bytes that correspond to the version number of the "major brand".
+			continue
+		}
+		if bytes.Equal(data[st:st+3], mp4) {
+			return "video/mp4"
+		}
+	}
+	return ""
+}
+
+type textSig struct{}
+
+func (textSig) match(data []byte, firstNonWS int) string {
+	// c.f. section 5, step 4.
+	for _, b := range data[firstNonWS:] {
+		switch {
+		case b <= 0x08,
+			b == 0x0B,
+			0x0E <= b && b <= 0x1A,
+			0x1C <= b && b <= 0x1F:
+			return ""
+		}
+	}
+	return "text/plain; charset=utf-8"
+}
diff --git a/contrib/go/_std_1.18/src/net/http/socks_bundle.go b/contrib/go/_std_1.19/src/net/http/socks_bundle.go
index e446669589..e446669589 100644
--- a/contrib/go/_std_1.18/src/net/http/socks_bundle.go
+++ b/contrib/go/_std_1.19/src/net/http/socks_bundle.go
diff --git a/contrib/go/_std_1.19/src/net/http/status.go b/contrib/go/_std_1.19/src/net/http/status.go
new file mode 100644
index 0000000000..cd90877ef0
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/http/status.go
@@ -0,0 +1,210 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package http
+
+// HTTP status codes as registered with IANA.
+// See: https://www.iana.org/assignments/http-status-codes/http-status-codes.xhtml
+const (
+	StatusContinue           = 100 // RFC 9110, 15.2.1
+	StatusSwitchingProtocols = 101 // RFC 9110, 15.2.2
+	StatusProcessing         = 102 // RFC 2518, 10.1
+	StatusEarlyHints         = 103 // RFC 8297
+
+	StatusOK                   = 200 // RFC 9110, 15.3.1
+	StatusCreated              = 201 // RFC 9110, 15.3.2
+	StatusAccepted             = 202 // RFC 9110, 15.3.3
+	StatusNonAuthoritativeInfo = 203 // RFC 9110, 15.3.4
+	StatusNoContent            = 204 // RFC 9110, 15.3.5
+	StatusResetContent         = 205 // RFC 9110, 15.3.6
+	StatusPartialContent       = 206 // RFC 9110, 15.3.7
+	StatusMultiStatus          = 207 // RFC 4918, 11.1
+	StatusAlreadyReported      = 208 // RFC 5842, 7.1
+	StatusIMUsed               = 226 // RFC 3229, 10.4.1
+
+	StatusMultipleChoices   = 300 // RFC 9110, 15.4.1
+	StatusMovedPermanently  = 301 // RFC 9110, 15.4.2
+	StatusFound             = 302 // RFC 9110, 15.4.3
+	StatusSeeOther          = 303 // RFC 9110, 15.4.4
+	StatusNotModified       = 304 // RFC 9110, 15.4.5
+	StatusUseProxy          = 305 // RFC 9110, 15.4.6
+	_                       = 306 // RFC 9110, 15.4.7 (Unused)
+	StatusTemporaryRedirect = 307 // RFC 9110, 15.4.8
+	StatusPermanentRedirect = 308 // RFC 9110, 15.4.9
+
+	StatusBadRequest                   = 400 // RFC 9110, 15.5.1
+	StatusUnauthorized                 = 401 // RFC 9110, 15.5.2
+	StatusPaymentRequired              = 402 // RFC 9110, 15.5.3
+	StatusForbidden                    = 403 // RFC 9110, 15.5.4
+	StatusNotFound                     = 404 // RFC 9110, 15.5.5
+	StatusMethodNotAllowed             = 405 // RFC 9110, 15.5.6
+	StatusNotAcceptable                = 406 // RFC 9110, 15.5.7
+	StatusProxyAuthRequired            = 407 // RFC 9110, 15.5.8
+	StatusRequestTimeout               = 408 // RFC 9110, 15.5.9
+	StatusConflict                     = 409 // RFC 9110, 15.5.10
+	StatusGone                         = 410 // RFC 9110, 15.5.11
+	StatusLengthRequired               = 411 // RFC 9110, 15.5.12
+	StatusPreconditionFailed           = 412 // RFC 9110, 15.5.13
+	StatusRequestEntityTooLarge        = 413 // RFC 9110, 15.5.14
+	StatusRequestURITooLong            = 414 // RFC 9110, 15.5.15
+	StatusUnsupportedMediaType         = 415 // RFC 9110, 15.5.16
+	StatusRequestedRangeNotSatisfiable = 416 // RFC 9110, 15.5.17
+	StatusExpectationFailed            = 417 // RFC 9110, 15.5.18
+	StatusTeapot                       = 418 // RFC 9110, 15.5.19 (Unused)
+	StatusMisdirectedRequest           = 421 // RFC 9110, 15.5.20
+	StatusUnprocessableEntity          = 422 // RFC 9110, 15.5.21
+	StatusLocked                       = 423 // RFC 4918, 11.3
+	StatusFailedDependency             = 424 // RFC 4918, 11.4
+	StatusTooEarly                     = 425 // RFC 8470, 5.2.
+	StatusUpgradeRequired              = 426 // RFC 9110, 15.5.22
+	StatusPreconditionRequired         = 428 // RFC 6585, 3
+	StatusTooManyRequests              = 429 // RFC 6585, 4
+	StatusRequestHeaderFieldsTooLarge  = 431 // RFC 6585, 5
+	StatusUnavailableForLegalReasons   = 451 // RFC 7725, 3
+
+	StatusInternalServerError           = 500 // RFC 9110, 15.6.1
+	StatusNotImplemented                = 501 // RFC 9110, 15.6.2
+	StatusBadGateway                    = 502 // RFC 9110, 15.6.3
+	StatusServiceUnavailable            = 503 // RFC 9110, 15.6.4
+	StatusGatewayTimeout                = 504 // RFC 9110, 15.6.5
+	StatusHTTPVersionNotSupported       = 505 // RFC 9110, 15.6.6
+	StatusVariantAlsoNegotiates         = 506 // RFC 2295, 8.1
+	StatusInsufficientStorage           = 507 // RFC 4918, 11.5
+	StatusLoopDetected                  = 508 // RFC 5842, 7.2
+	StatusNotExtended                   = 510 // RFC 2774, 7
+	StatusNetworkAuthenticationRequired = 511 // RFC 6585, 6
+)
+
+// StatusText returns a text for the HTTP status code. It returns the empty
+// string if the code is unknown.
+func StatusText(code int) string {
+	switch code {
+	case StatusContinue:
+		return "Continue"
+	case StatusSwitchingProtocols:
+		return "Switching Protocols"
+	case StatusProcessing:
+		return "Processing"
+	case StatusEarlyHints:
+		return "Early Hints"
+	case StatusOK:
+		return "OK"
+	case StatusCreated:
+		return "Created"
+	case StatusAccepted:
+		return "Accepted"
+	case StatusNonAuthoritativeInfo:
+		return "Non-Authoritative Information"
+	case StatusNoContent:
+		return "No Content"
+	case StatusResetContent:
+		return "Reset Content"
+	case StatusPartialContent:
+		return "Partial Content"
+	case StatusMultiStatus:
+		return "Multi-Status"
+	case StatusAlreadyReported:
+		return "Already Reported"
+	case StatusIMUsed:
+		return "IM Used"
+	case StatusMultipleChoices:
+		return "Multiple Choices"
+	case StatusMovedPermanently:
+		return "Moved Permanently"
+	case StatusFound:
+		return "Found"
+	case StatusSeeOther:
+		return "See Other"
+	case StatusNotModified:
+		return "Not Modified"
+	case StatusUseProxy:
+		return "Use Proxy"
+	case StatusTemporaryRedirect:
+		return "Temporary Redirect"
+	case StatusPermanentRedirect:
+		return "Permanent Redirect"
+	case StatusBadRequest:
+		return "Bad Request"
+	case StatusUnauthorized:
+		return "Unauthorized"
+	case StatusPaymentRequired:
+		return "Payment Required"
+	case StatusForbidden:
+		return "Forbidden"
+	case StatusNotFound:
+		return "Not Found"
+	case StatusMethodNotAllowed:
+		return "Method Not Allowed"
+	case StatusNotAcceptable:
+		return "Not Acceptable"
+	case StatusProxyAuthRequired:
+		return "Proxy Authentication Required"
+	case StatusRequestTimeout:
+		return "Request Timeout"
+	case StatusConflict:
+		return "Conflict"
+	case StatusGone:
+		return "Gone"
+	case StatusLengthRequired:
+		return "Length Required"
+	case StatusPreconditionFailed:
+		return "Precondition Failed"
+	case StatusRequestEntityTooLarge:
+		return "Request Entity Too Large"
+	case StatusRequestURITooLong:
+		return "Request URI Too Long"
+	case StatusUnsupportedMediaType:
+		return "Unsupported Media Type"
+	case StatusRequestedRangeNotSatisfiable:
+		return "Requested Range Not Satisfiable"
+	case StatusExpectationFailed:
+		return "Expectation Failed"
+	case StatusTeapot:
+		return "I'm a teapot"
+	case StatusMisdirectedRequest:
+		return "Misdirected Request"
+	case StatusUnprocessableEntity:
+		return "Unprocessable Entity"
+	case StatusLocked:
+		return "Locked"
+	case StatusFailedDependency:
+		return "Failed Dependency"
+	case StatusTooEarly:
+		return "Too Early"
+	case StatusUpgradeRequired:
+		return "Upgrade Required"
+	case StatusPreconditionRequired:
+		return "Precondition Required"
+	case StatusTooManyRequests:
+		return "Too Many Requests"
+	case StatusRequestHeaderFieldsTooLarge:
+		return "Request Header Fields Too Large"
+	case StatusUnavailableForLegalReasons:
+		return "Unavailable For Legal Reasons"
+	case StatusInternalServerError:
+		return "Internal Server Error"
+	case StatusNotImplemented:
+		return "Not Implemented"
+	case StatusBadGateway:
+		return "Bad Gateway"
+	case StatusServiceUnavailable:
+		return "Service Unavailable"
+	case StatusGatewayTimeout:
+		return "Gateway Timeout"
+	case StatusHTTPVersionNotSupported:
+		return "HTTP Version Not Supported"
+	case StatusVariantAlsoNegotiates:
+		return "Variant Also Negotiates"
+	case StatusInsufficientStorage:
+		return "Insufficient Storage"
+	case StatusLoopDetected:
+		return "Loop Detected"
+	case StatusNotExtended:
+		return "Not Extended"
+	case StatusNetworkAuthenticationRequired:
+		return "Network Authentication Required"
+	default:
+		return ""
+	}
+}
diff --git a/contrib/go/_std_1.19/src/net/http/transfer.go b/contrib/go/_std_1.19/src/net/http/transfer.go
new file mode 100644
index 0000000000..4583c6b453
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/http/transfer.go
@@ -0,0 +1,1131 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package http
+
+import (
+	"bufio"
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+	"net/http/httptrace"
+	"net/http/internal"
+	"net/http/internal/ascii"
+	"net/textproto"
+	"reflect"
+	"sort"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+
+	"golang.org/x/net/http/httpguts"
+)
+
+// ErrLineTooLong is returned when reading request or response bodies
+// with malformed chunked encoding.
+var ErrLineTooLong = internal.ErrLineTooLong
+
+type errorReader struct {
+	err error
+}
+
+func (r errorReader) Read(p []byte) (n int, err error) {
+	return 0, r.err
+}
+
+type byteReader struct {
+	b    byte
+	done bool
+}
+
+func (br *byteReader) Read(p []byte) (n int, err error) {
+	if br.done {
+		return 0, io.EOF
+	}
+	if len(p) == 0 {
+		return 0, nil
+	}
+	br.done = true
+	p[0] = br.b
+	return 1, io.EOF
+}
+
+// transferWriter inspects the fields of a user-supplied Request or Response,
+// sanitizes them without changing the user object and provides methods for
+// writing the respective header, body and trailer in wire format.
+type transferWriter struct {
+	Method           string
+	Body             io.Reader
+	BodyCloser       io.Closer
+	ResponseToHEAD   bool
+	ContentLength    int64 // -1 means unknown, 0 means exactly none
+	Close            bool
+	TransferEncoding []string
+	Header           Header
+	Trailer          Header
+	IsResponse       bool
+	bodyReadError    error // any non-EOF error from reading Body
+
+	FlushHeaders bool            // flush headers to network before body
+	ByteReadCh   chan readResult // non-nil if probeRequestBody called
+}
+
+func newTransferWriter(r any) (t *transferWriter, err error) {
+	t = &transferWriter{}
+
+	// Extract relevant fields
+	atLeastHTTP11 := false
+	switch rr := r.(type) {
+	case *Request:
+		if rr.ContentLength != 0 && rr.Body == nil {
+			return nil, fmt.Errorf("http: Request.ContentLength=%d with nil Body", rr.ContentLength)
+		}
+		t.Method = valueOrDefault(rr.Method, "GET")
+		t.Close = rr.Close
+		t.TransferEncoding = rr.TransferEncoding
+		t.Header = rr.Header
+		t.Trailer = rr.Trailer
+		t.Body = rr.Body
+		t.BodyCloser = rr.Body
+		t.ContentLength = rr.outgoingLength()
+		if t.ContentLength < 0 && len(t.TransferEncoding) == 0 && t.shouldSendChunkedRequestBody() {
+			t.TransferEncoding = []string{"chunked"}
+		}
+		// If there's a body, conservatively flush the headers
+		// to any bufio.Writer we're writing to, just in case
+		// the server needs the headers early, before we copy
+		// the body and possibly block. We make an exception
+		// for the common standard library in-memory types,
+		// though, to avoid unnecessary TCP packets on the
+		// wire. (Issue 22088.)
+		if t.ContentLength != 0 && !isKnownInMemoryReader(t.Body) {
+			t.FlushHeaders = true
+		}
+
+		atLeastHTTP11 = true // Transport requests are always 1.1 or 2.0
+	case *Response:
+		t.IsResponse = true
+		if rr.Request != nil {
+			t.Method = rr.Request.Method
+		}
+		t.Body = rr.Body
+		t.BodyCloser = rr.Body
+		t.ContentLength = rr.ContentLength
+		t.Close = rr.Close
+		t.TransferEncoding = rr.TransferEncoding
+		t.Header = rr.Header
+		t.Trailer = rr.Trailer
+		atLeastHTTP11 = rr.ProtoAtLeast(1, 1)
+		t.ResponseToHEAD = noResponseBodyExpected(t.Method)
+	}
+
+	// Sanitize Body,ContentLength,TransferEncoding
+	if t.ResponseToHEAD {
+		t.Body = nil
+		if chunked(t.TransferEncoding) {
+			t.ContentLength = -1
+		}
+	} else {
+		if !atLeastHTTP11 || t.Body == nil {
+			t.TransferEncoding = nil
+		}
+		if chunked(t.TransferEncoding) {
+			t.ContentLength = -1
+		} else if t.Body == nil { // no chunking, no body
+			t.ContentLength = 0
+		}
+	}
+
+	// Sanitize Trailer
+	if !chunked(t.TransferEncoding) {
+		t.Trailer = nil
+	}
+
+	return t, nil
+}
+
+// shouldSendChunkedRequestBody reports whether we should try to send a
+// chunked request body to the server. In particular, the case we really
+// want to prevent is sending a GET or other typically-bodyless request to a
+// server with a chunked body when the body has zero bytes, since GETs with
+// bodies (while acceptable according to specs), even zero-byte chunked
+// bodies, are approximately never seen in the wild and confuse most
+// servers. See Issue 18257, as one example.
+//
+// The only reason we'd send such a request is if the user set the Body to a
+// non-nil value (say, io.NopCloser(bytes.NewReader(nil))) and didn't
+// set ContentLength, or NewRequest set it to -1 (unknown), so then we assume
+// there's bytes to send.
+//
+// This code tries to read a byte from the Request.Body in such cases to see
+// whether the body actually has content (super rare) or is actually just
+// a non-nil content-less ReadCloser (the more common case). In that more
+// common case, we act as if their Body were nil instead, and don't send
+// a body.
+func (t *transferWriter) shouldSendChunkedRequestBody() bool {
+	// Note that t.ContentLength is the corrected content length
+	// from rr.outgoingLength, so 0 actually means zero, not unknown.
+	if t.ContentLength >= 0 || t.Body == nil { // redundant checks; caller did them
+		return false
+	}
+	if t.Method == "CONNECT" {
+		return false
+	}
+	if requestMethodUsuallyLacksBody(t.Method) {
+		// Only probe the Request.Body for GET/HEAD/DELETE/etc
+		// requests, because it's only those types of requests
+		// that confuse servers.
+		t.probeRequestBody() // adjusts t.Body, t.ContentLength
+		return t.Body != nil
+	}
+	// For all other request types (PUT, POST, PATCH, or anything
+	// made-up we've never heard of), assume it's normal and the server
+	// can deal with a chunked request body. Maybe we'll adjust this
+	// later.
+	return true
+}
+
+// probeRequestBody reads a byte from t.Body to see whether it's empty
+// (returns io.EOF right away).
+//
+// But because we've had problems with this blocking users in the past
+// (issue 17480) when the body is a pipe (perhaps waiting on the response
+// headers before the pipe is fed data), we need to be careful and bound how
+// long we wait for it. This delay will only affect users if all the following
+// are true:
+//   - the request body blocks
+//   - the content length is not set (or set to -1)
+//   - the method doesn't usually have a body (GET, HEAD, DELETE, ...)
+//   - there is no transfer-encoding=chunked already set.
+//
+// In other words, this delay will not normally affect anybody, and there
+// are workarounds if it does.
+func (t *transferWriter) probeRequestBody() {
+	t.ByteReadCh = make(chan readResult, 1)
+	go func(body io.Reader) {
+		var buf [1]byte
+		var rres readResult
+		rres.n, rres.err = body.Read(buf[:])
+		if rres.n == 1 {
+			rres.b = buf[0]
+		}
+		t.ByteReadCh <- rres
+		close(t.ByteReadCh)
+	}(t.Body)
+	timer := time.NewTimer(200 * time.Millisecond)
+	select {
+	case rres := <-t.ByteReadCh:
+		timer.Stop()
+		if rres.n == 0 && rres.err == io.EOF {
+			// It was empty.
+			t.Body = nil
+			t.ContentLength = 0
+		} else if rres.n == 1 {
+			if rres.err != nil {
+				t.Body = io.MultiReader(&byteReader{b: rres.b}, errorReader{rres.err})
+			} else {
+				t.Body = io.MultiReader(&byteReader{b: rres.b}, t.Body)
+			}
+		} else if rres.err != nil {
+			t.Body = errorReader{rres.err}
+		}
+	case <-timer.C:
+		// Too slow. Don't wait. Read it later, and keep
+		// assuming that this is ContentLength == -1
+		// (unknown), which means we'll send a
+		// "Transfer-Encoding: chunked" header.
+		t.Body = io.MultiReader(finishAsyncByteRead{t}, t.Body)
+		// Request that Request.Write flush the headers to the
+		// network before writing the body, since our body may not
+		// become readable until it's seen the response headers.
+		t.FlushHeaders = true
+	}
+}
+
+func noResponseBodyExpected(requestMethod string) bool {
+	return requestMethod == "HEAD"
+}
+
+func (t *transferWriter) shouldSendContentLength() bool {
+	if chunked(t.TransferEncoding) {
+		return false
+	}
+	if t.ContentLength > 0 {
+		return true
+	}
+	if t.ContentLength < 0 {
+		return false
+	}
+	// Many servers expect a Content-Length for these methods
+	if t.Method == "POST" || t.Method == "PUT" || t.Method == "PATCH" {
+		return true
+	}
+	if t.ContentLength == 0 && isIdentity(t.TransferEncoding) {
+		if t.Method == "GET" || t.Method == "HEAD" {
+			return false
+		}
+		return true
+	}
+
+	return false
+}
+
+func (t *transferWriter) writeHeader(w io.Writer, trace *httptrace.ClientTrace) error {
+	if t.Close && !hasToken(t.Header.get("Connection"), "close") {
+		if _, err := io.WriteString(w, "Connection: close\r\n"); err != nil {
+			return err
+		}
+		if trace != nil && trace.WroteHeaderField != nil {
+			trace.WroteHeaderField("Connection", []string{"close"})
+		}
+	}
+
+	// Write Content-Length and/or Transfer-Encoding whose values are a
+	// function of the sanitized field triple (Body, ContentLength,
+	// TransferEncoding)
+	if t.shouldSendContentLength() {
+		if _, err := io.WriteString(w, "Content-Length: "); err != nil {
+			return err
+		}
+		if _, err := io.WriteString(w, strconv.FormatInt(t.ContentLength, 10)+"\r\n"); err != nil {
+			return err
+		}
+		if trace != nil && trace.WroteHeaderField != nil {
+			trace.WroteHeaderField("Content-Length", []string{strconv.FormatInt(t.ContentLength, 10)})
+		}
+	} else if chunked(t.TransferEncoding) {
+		if _, err := io.WriteString(w, "Transfer-Encoding: chunked\r\n"); err != nil {
+			return err
+		}
+		if trace != nil && trace.WroteHeaderField != nil {
+			trace.WroteHeaderField("Transfer-Encoding", []string{"chunked"})
+		}
+	}
+
+	// Write Trailer header
+	if t.Trailer != nil {
+		keys := make([]string, 0, len(t.Trailer))
+		for k := range t.Trailer {
+			k = CanonicalHeaderKey(k)
+			switch k {
+			case "Transfer-Encoding", "Trailer", "Content-Length":
+				return badStringError("invalid Trailer key", k)
+			}
+			keys = append(keys, k)
+		}
+		if len(keys) > 0 {
+			sort.Strings(keys)
+			// TODO: could do better allocation-wise here, but trailers are rare,
+			// so being lazy for now.
+			if _, err := io.WriteString(w, "Trailer: "+strings.Join(keys, ",")+"\r\n"); err != nil {
+				return err
+			}
+			if trace != nil && trace.WroteHeaderField != nil {
+				trace.WroteHeaderField("Trailer", keys)
+			}
+		}
+	}
+
+	return nil
+}
+
+// always closes t.BodyCloser
+func (t *transferWriter) writeBody(w io.Writer) (err error) {
+	var ncopy int64
+	closed := false
+	defer func() {
+		if closed || t.BodyCloser == nil {
+			return
+		}
+		if closeErr := t.BodyCloser.Close(); closeErr != nil && err == nil {
+			err = closeErr
+		}
+	}()
+
+	// Write body. We "unwrap" the body first if it was wrapped in a
+	// nopCloser or readTrackingBody. This is to ensure that we can take advantage of
+	// OS-level optimizations in the event that the body is an
+	// *os.File.
+	if t.Body != nil {
+		var body = t.unwrapBody()
+		if chunked(t.TransferEncoding) {
+			if bw, ok := w.(*bufio.Writer); ok && !t.IsResponse {
+				w = &internal.FlushAfterChunkWriter{Writer: bw}
+			}
+			cw := internal.NewChunkedWriter(w)
+			_, err = t.doBodyCopy(cw, body)
+			if err == nil {
+				err = cw.Close()
+			}
+		} else if t.ContentLength == -1 {
+			dst := w
+			if t.Method == "CONNECT" {
+				dst = bufioFlushWriter{dst}
+			}
+			ncopy, err = t.doBodyCopy(dst, body)
+		} else {
+			ncopy, err = t.doBodyCopy(w, io.LimitReader(body, t.ContentLength))
+			if err != nil {
+				return err
+			}
+			var nextra int64
+			nextra, err = t.doBodyCopy(io.Discard, body)
+			ncopy += nextra
+		}
+		if err != nil {
+			return err
+		}
+	}
+	if t.BodyCloser != nil {
+		closed = true
+		if err := t.BodyCloser.Close(); err != nil {
+			return err
+		}
+	}
+
+	if !t.ResponseToHEAD && t.ContentLength != -1 && t.ContentLength != ncopy {
+		return fmt.Errorf("http: ContentLength=%d with Body length %d",
+			t.ContentLength, ncopy)
+	}
+
+	if chunked(t.TransferEncoding) {
+		// Write Trailer header
+		if t.Trailer != nil {
+			if err := t.Trailer.Write(w); err != nil {
+				return err
+			}
+		}
+		// Last chunk, empty trailer
+		_, err = io.WriteString(w, "\r\n")
+	}
+	return err
+}
+
+// doBodyCopy wraps a copy operation, with any resulting error also
+// being saved in bodyReadError.
+//
+// This function is only intended for use in writeBody.
+func (t *transferWriter) doBodyCopy(dst io.Writer, src io.Reader) (n int64, err error) {
+	n, err = io.Copy(dst, src)
+	if err != nil && err != io.EOF {
+		t.bodyReadError = err
+	}
+	return
+}
+
+// unwrapBodyReader unwraps the body's inner reader if it's a
+// nopCloser. This is to ensure that body writes sourced from local
+// files (*os.File types) are properly optimized.
+//
+// This function is only intended for use in writeBody.
+func (t *transferWriter) unwrapBody() io.Reader {
+	if r, ok := unwrapNopCloser(t.Body); ok {
+		return r
+	}
+	if r, ok := t.Body.(*readTrackingBody); ok {
+		r.didRead = true
+		return r.ReadCloser
+	}
+	return t.Body
+}
+
+type transferReader struct {
+	// Input
+	Header        Header
+	StatusCode    int
+	RequestMethod string
+	ProtoMajor    int
+	ProtoMinor    int
+	// Output
+	Body          io.ReadCloser
+	ContentLength int64
+	Chunked       bool
+	Close         bool
+	Trailer       Header
+}
+
+func (t *transferReader) protoAtLeast(m, n int) bool {
+	return t.ProtoMajor > m || (t.ProtoMajor == m && t.ProtoMinor >= n)
+}
+
+// bodyAllowedForStatus reports whether a given response status code
+// permits a body. See RFC 7230, section 3.3.
+func bodyAllowedForStatus(status int) bool {
+	switch {
+	case status >= 100 && status <= 199:
+		return false
+	case status == 204:
+		return false
+	case status == 304:
+		return false
+	}
+	return true
+}
+
+var (
+	suppressedHeaders304    = []string{"Content-Type", "Content-Length", "Transfer-Encoding"}
+	suppressedHeadersNoBody = []string{"Content-Length", "Transfer-Encoding"}
+	excludedHeadersNoBody   = map[string]bool{"Content-Length": true, "Transfer-Encoding": true}
+)
+
+func suppressedHeaders(status int) []string {
+	switch {
+	case status == 304:
+		// RFC 7232 section 4.1
+		return suppressedHeaders304
+	case !bodyAllowedForStatus(status):
+		return suppressedHeadersNoBody
+	}
+	return nil
+}
+
+// msg is *Request or *Response.
+func readTransfer(msg any, r *bufio.Reader) (err error) {
+	t := &transferReader{RequestMethod: "GET"}
+
+	// Unify input
+	isResponse := false
+	switch rr := msg.(type) {
+	case *Response:
+		t.Header = rr.Header
+		t.StatusCode = rr.StatusCode
+		t.ProtoMajor = rr.ProtoMajor
+		t.ProtoMinor = rr.ProtoMinor
+		t.Close = shouldClose(t.ProtoMajor, t.ProtoMinor, t.Header, true)
+		isResponse = true
+		if rr.Request != nil {
+			t.RequestMethod = rr.Request.Method
+		}
+	case *Request:
+		t.Header = rr.Header
+		t.RequestMethod = rr.Method
+		t.ProtoMajor = rr.ProtoMajor
+		t.ProtoMinor = rr.ProtoMinor
+		// Transfer semantics for Requests are exactly like those for
+		// Responses with status code 200, responding to a GET method
+		t.StatusCode = 200
+		t.Close = rr.Close
+	default:
+		panic("unexpected type")
+	}
+
+	// Default to HTTP/1.1
+	if t.ProtoMajor == 0 && t.ProtoMinor == 0 {
+		t.ProtoMajor, t.ProtoMinor = 1, 1
+	}
+
+	// Transfer-Encoding: chunked, and overriding Content-Length.
+	if err := t.parseTransferEncoding(); err != nil {
+		return err
+	}
+
+	realLength, err := fixLength(isResponse, t.StatusCode, t.RequestMethod, t.Header, t.Chunked)
+	if err != nil {
+		return err
+	}
+	if isResponse && t.RequestMethod == "HEAD" {
+		if n, err := parseContentLength(t.Header.get("Content-Length")); err != nil {
+			return err
+		} else {
+			t.ContentLength = n
+		}
+	} else {
+		t.ContentLength = realLength
+	}
+
+	// Trailer
+	t.Trailer, err = fixTrailer(t.Header, t.Chunked)
+	if err != nil {
+		return err
+	}
+
+	// If there is no Content-Length or chunked Transfer-Encoding on a *Response
+	// and the status is not 1xx, 204 or 304, then the body is unbounded.
+	// See RFC 7230, section 3.3.
+	switch msg.(type) {
+	case *Response:
+		if realLength == -1 && !t.Chunked && bodyAllowedForStatus(t.StatusCode) {
+			// Unbounded body.
+			t.Close = true
+		}
+	}
+
+	// Prepare body reader. ContentLength < 0 means chunked encoding
+	// or close connection when finished, since multipart is not supported yet
+	switch {
+	case t.Chunked:
+		if noResponseBodyExpected(t.RequestMethod) || !bodyAllowedForStatus(t.StatusCode) {
+			t.Body = NoBody
+		} else {
+			t.Body = &body{src: internal.NewChunkedReader(r), hdr: msg, r: r, closing: t.Close}
+		}
+	case realLength == 0:
+		t.Body = NoBody
+	case realLength > 0:
+		t.Body = &body{src: io.LimitReader(r, realLength), closing: t.Close}
+	default:
+		// realLength < 0, i.e. "Content-Length" not mentioned in header
+		if t.Close {
+			// Close semantics (i.e. HTTP/1.0)
+			t.Body = &body{src: r, closing: t.Close}
+		} else {
+			// Persistent connection (i.e. HTTP/1.1)
+			t.Body = NoBody
+		}
+	}
+
+	// Unify output
+	switch rr := msg.(type) {
+	case *Request:
+		rr.Body = t.Body
+		rr.ContentLength = t.ContentLength
+		if t.Chunked {
+			rr.TransferEncoding = []string{"chunked"}
+		}
+		rr.Close = t.Close
+		rr.Trailer = t.Trailer
+	case *Response:
+		rr.Body = t.Body
+		rr.ContentLength = t.ContentLength
+		if t.Chunked {
+			rr.TransferEncoding = []string{"chunked"}
+		}
+		rr.Close = t.Close
+		rr.Trailer = t.Trailer
+	}
+
+	return nil
+}
+
+// Checks whether chunked is part of the encodings stack
+func chunked(te []string) bool { return len(te) > 0 && te[0] == "chunked" }
+
+// Checks whether the encoding is explicitly "identity".
+func isIdentity(te []string) bool { return len(te) == 1 && te[0] == "identity" }
+
+// unsupportedTEError reports unsupported transfer-encodings.
+type unsupportedTEError struct {
+	err string
+}
+
+func (uste *unsupportedTEError) Error() string {
+	return uste.err
+}
+
+// isUnsupportedTEError checks if the error is of type
+// unsupportedTEError. It is usually invoked with a non-nil err.
+func isUnsupportedTEError(err error) bool {
+	_, ok := err.(*unsupportedTEError)
+	return ok
+}
+
+// parseTransferEncoding sets t.Chunked based on the Transfer-Encoding header.
+func (t *transferReader) parseTransferEncoding() error {
+	raw, present := t.Header["Transfer-Encoding"]
+	if !present {
+		return nil
+	}
+	delete(t.Header, "Transfer-Encoding")
+
+	// Issue 12785; ignore Transfer-Encoding on HTTP/1.0 requests.
+	if !t.protoAtLeast(1, 1) {
+		return nil
+	}
+
+	// Like nginx, we only support a single Transfer-Encoding header field, and
+	// only if set to "chunked". This is one of the most security sensitive
+	// surfaces in HTTP/1.1 due to the risk of request smuggling, so we keep it
+	// strict and simple.
+	if len(raw) != 1 {
+		return &unsupportedTEError{fmt.Sprintf("too many transfer encodings: %q", raw)}
+	}
+	if !ascii.EqualFold(raw[0], "chunked") {
+		return &unsupportedTEError{fmt.Sprintf("unsupported transfer encoding: %q", raw[0])}
+	}
+
+	// RFC 7230 3.3.2 says "A sender MUST NOT send a Content-Length header field
+	// in any message that contains a Transfer-Encoding header field."
+	//
+	// but also: "If a message is received with both a Transfer-Encoding and a
+	// Content-Length header field, the Transfer-Encoding overrides the
+	// Content-Length. Such a message might indicate an attempt to perform
+	// request smuggling (Section 9.5) or response splitting (Section 9.4) and
+	// ought to be handled as an error. A sender MUST remove the received
+	// Content-Length field prior to forwarding such a message downstream."
+	//
+	// Reportedly, these appear in the wild.
+	delete(t.Header, "Content-Length")
+
+	t.Chunked = true
+	return nil
+}
+
+// Determine the expected body length, using RFC 7230 Section 3.3. This
+// function is not a method, because ultimately it should be shared by
+// ReadResponse and ReadRequest.
+func fixLength(isResponse bool, status int, requestMethod string, header Header, chunked bool) (int64, error) {
+	isRequest := !isResponse
+	contentLens := header["Content-Length"]
+
+	// Hardening against HTTP request smuggling
+	if len(contentLens) > 1 {
+		// Per RFC 7230 Section 3.3.2, prevent multiple
+		// Content-Length headers if they differ in value.
+		// If there are dups of the value, remove the dups.
+		// See Issue 16490.
+		first := textproto.TrimString(contentLens[0])
+		for _, ct := range contentLens[1:] {
+			if first != textproto.TrimString(ct) {
+				return 0, fmt.Errorf("http: message cannot contain multiple Content-Length headers; got %q", contentLens)
+			}
+		}
+
+		// deduplicate Content-Length
+		header.Del("Content-Length")
+		header.Add("Content-Length", first)
+
+		contentLens = header["Content-Length"]
+	}
+
+	// Logic based on response type or status
+	if noResponseBodyExpected(requestMethod) {
+		// For HTTP requests, as part of hardening against request
+		// smuggling (RFC 7230), don't allow a Content-Length header for
+		// methods which don't permit bodies. As an exception, allow
+		// exactly one Content-Length header if its value is "0".
+		if isRequest && len(contentLens) > 0 && !(len(contentLens) == 1 && contentLens[0] == "0") {
+			return 0, fmt.Errorf("http: method cannot contain a Content-Length; got %q", contentLens)
+		}
+		return 0, nil
+	}
+	if status/100 == 1 {
+		return 0, nil
+	}
+	switch status {
+	case 204, 304:
+		return 0, nil
+	}
+
+	// Logic based on Transfer-Encoding
+	if chunked {
+		return -1, nil
+	}
+
+	// Logic based on Content-Length
+	var cl string
+	if len(contentLens) == 1 {
+		cl = textproto.TrimString(contentLens[0])
+	}
+	if cl != "" {
+		n, err := parseContentLength(cl)
+		if err != nil {
+			return -1, err
+		}
+		return n, nil
+	}
+	header.Del("Content-Length")
+
+	if isRequest {
+		// RFC 7230 neither explicitly permits nor forbids an
+		// entity-body on a GET request so we permit one if
+		// declared, but we default to 0 here (not -1 below)
+		// if there's no mention of a body.
+		// Likewise, all other request methods are assumed to have
+		// no body if neither Transfer-Encoding chunked nor a
+		// Content-Length are set.
+		return 0, nil
+	}
+
+	// Body-EOF logic based on other methods (like closing, or chunked coding)
+	return -1, nil
+}
+
+// Determine whether to hang up after sending a request and body, or
+// receiving a response and body
+// 'header' is the request headers
+func shouldClose(major, minor int, header Header, removeCloseHeader bool) bool {
+	if major < 1 {
+		return true
+	}
+
+	conv := header["Connection"]
+	hasClose := httpguts.HeaderValuesContainsToken(conv, "close")
+	if major == 1 && minor == 0 {
+		return hasClose || !httpguts.HeaderValuesContainsToken(conv, "keep-alive")
+	}
+
+	if hasClose && removeCloseHeader {
+		header.Del("Connection")
+	}
+
+	return hasClose
+}
+
+// Parse the trailer header
+func fixTrailer(header Header, chunked bool) (Header, error) {
+	vv, ok := header["Trailer"]
+	if !ok {
+		return nil, nil
+	}
+	if !chunked {
+		// Trailer and no chunking:
+		// this is an invalid use case for trailer header.
+		// Nevertheless, no error will be returned and we
+		// let users decide if this is a valid HTTP message.
+		// The Trailer header will be kept in Response.Header
+		// but not populate Response.Trailer.
+		// See issue #27197.
+		return nil, nil
+	}
+	header.Del("Trailer")
+
+	trailer := make(Header)
+	var err error
+	for _, v := range vv {
+		foreachHeaderElement(v, func(key string) {
+			key = CanonicalHeaderKey(key)
+			switch key {
+			case "Transfer-Encoding", "Trailer", "Content-Length":
+				if err == nil {
+					err = badStringError("bad trailer key", key)
+					return
+				}
+			}
+			trailer[key] = nil
+		})
+	}
+	if err != nil {
+		return nil, err
+	}
+	if len(trailer) == 0 {
+		return nil, nil
+	}
+	return trailer, nil
+}
+
+// body turns a Reader into a ReadCloser.
+// Close ensures that the body has been fully read
+// and then reads the trailer if necessary.
+type body struct {
+	src          io.Reader
+	hdr          any           // non-nil (Response or Request) value means read trailer
+	r            *bufio.Reader // underlying wire-format reader for the trailer
+	closing      bool          // is the connection to be closed after reading body?
+	doEarlyClose bool          // whether Close should stop early
+
+	mu         sync.Mutex // guards following, and calls to Read and Close
+	sawEOF     bool
+	closed     bool
+	earlyClose bool   // Close called and we didn't read to the end of src
+	onHitEOF   func() // if non-nil, func to call when EOF is Read
+}
+
+// ErrBodyReadAfterClose is returned when reading a Request or Response
+// Body after the body has been closed. This typically happens when the body is
+// read after an HTTP Handler calls WriteHeader or Write on its
+// ResponseWriter.
+var ErrBodyReadAfterClose = errors.New("http: invalid Read on closed Body")
+
+func (b *body) Read(p []byte) (n int, err error) {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	if b.closed {
+		return 0, ErrBodyReadAfterClose
+	}
+	return b.readLocked(p)
+}
+
+// Must hold b.mu.
+func (b *body) readLocked(p []byte) (n int, err error) {
+	if b.sawEOF {
+		return 0, io.EOF
+	}
+	n, err = b.src.Read(p)
+
+	if err == io.EOF {
+		b.sawEOF = true
+		// Chunked case. Read the trailer.
+		if b.hdr != nil {
+			if e := b.readTrailer(); e != nil {
+				err = e
+				// Something went wrong in the trailer, we must not allow any
+				// further reads of any kind to succeed from body, nor any
+				// subsequent requests on the server connection. See
+				// golang.org/issue/12027
+				b.sawEOF = false
+				b.closed = true
+			}
+			b.hdr = nil
+		} else {
+			// If the server declared the Content-Length, our body is a LimitedReader
+			// and we need to check whether this EOF arrived early.
+			if lr, ok := b.src.(*io.LimitedReader); ok && lr.N > 0 {
+				err = io.ErrUnexpectedEOF
+			}
+		}
+	}
+
+	// If we can return an EOF here along with the read data, do
+	// so. This is optional per the io.Reader contract, but doing
+	// so helps the HTTP transport code recycle its connection
+	// earlier (since it will see this EOF itself), even if the
+	// client doesn't do future reads or Close.
+	if err == nil && n > 0 {
+		if lr, ok := b.src.(*io.LimitedReader); ok && lr.N == 0 {
+			err = io.EOF
+			b.sawEOF = true
+		}
+	}
+
+	if b.sawEOF && b.onHitEOF != nil {
+		b.onHitEOF()
+	}
+
+	return n, err
+}
+
+var (
+	singleCRLF = []byte("\r\n")
+	doubleCRLF = []byte("\r\n\r\n")
+)
+
+func seeUpcomingDoubleCRLF(r *bufio.Reader) bool {
+	for peekSize := 4; ; peekSize++ {
+		// This loop stops when Peek returns an error,
+		// which it does when r's buffer has been filled.
+		buf, err := r.Peek(peekSize)
+		if bytes.HasSuffix(buf, doubleCRLF) {
+			return true
+		}
+		if err != nil {
+			break
+		}
+	}
+	return false
+}
+
+var errTrailerEOF = errors.New("http: unexpected EOF reading trailer")
+
+func (b *body) readTrailer() error {
+	// The common case, since nobody uses trailers.
+	buf, err := b.r.Peek(2)
+	if bytes.Equal(buf, singleCRLF) {
+		b.r.Discard(2)
+		return nil
+	}
+	if len(buf) < 2 {
+		return errTrailerEOF
+	}
+	if err != nil {
+		return err
+	}
+
+	// Make sure there's a header terminator coming up, to prevent
+	// a DoS with an unbounded size Trailer. It's not easy to
+	// slip in a LimitReader here, as textproto.NewReader requires
+	// a concrete *bufio.Reader. Also, we can't get all the way
+	// back up to our conn's LimitedReader that *might* be backing
+	// this bufio.Reader. Instead, a hack: we iteratively Peek up
+	// to the bufio.Reader's max size, looking for a double CRLF.
+	// This limits the trailer to the underlying buffer size, typically 4kB.
+	if !seeUpcomingDoubleCRLF(b.r) {
+		return errors.New("http: suspiciously long trailer after chunked body")
+	}
+
+	hdr, err := textproto.NewReader(b.r).ReadMIMEHeader()
+	if err != nil {
+		if err == io.EOF {
+			return errTrailerEOF
+		}
+		return err
+	}
+	switch rr := b.hdr.(type) {
+	case *Request:
+		mergeSetHeader(&rr.Trailer, Header(hdr))
+	case *Response:
+		mergeSetHeader(&rr.Trailer, Header(hdr))
+	}
+	return nil
+}
+
+func mergeSetHeader(dst *Header, src Header) {
+	if *dst == nil {
+		*dst = src
+		return
+	}
+	for k, vv := range src {
+		(*dst)[k] = vv
+	}
+}
+
+// unreadDataSizeLocked returns the number of bytes of unread input.
+// It returns -1 if unknown.
+// b.mu must be held.
+func (b *body) unreadDataSizeLocked() int64 {
+	if lr, ok := b.src.(*io.LimitedReader); ok {
+		return lr.N
+	}
+	return -1
+}
+
+func (b *body) Close() error {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	if b.closed {
+		return nil
+	}
+	var err error
+	switch {
+	case b.sawEOF:
+		// Already saw EOF, so no need going to look for it.
+	case b.hdr == nil && b.closing:
+		// no trailer and closing the connection next.
+		// no point in reading to EOF.
+	case b.doEarlyClose:
+		// Read up to maxPostHandlerReadBytes bytes of the body, looking
+		// for EOF (and trailers), so we can re-use this connection.
+		if lr, ok := b.src.(*io.LimitedReader); ok && lr.N > maxPostHandlerReadBytes {
+			// There was a declared Content-Length, and we have more bytes remaining
+			// than our maxPostHandlerReadBytes tolerance. So, give up.
+			b.earlyClose = true
+		} else {
+			var n int64
+			// Consume the body, or, which will also lead to us reading
+			// the trailer headers after the body, if present.
+			n, err = io.CopyN(io.Discard, bodyLocked{b}, maxPostHandlerReadBytes)
+			if err == io.EOF {
+				err = nil
+			}
+			if n == maxPostHandlerReadBytes {
+				b.earlyClose = true
+			}
+		}
+	default:
+		// Fully consume the body, which will also lead to us reading
+		// the trailer headers after the body, if present.
+		_, err = io.Copy(io.Discard, bodyLocked{b})
+	}
+	b.closed = true
+	return err
+}
+
+func (b *body) didEarlyClose() bool {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	return b.earlyClose
+}
+
+// bodyRemains reports whether future Read calls might
+// yield data.
+func (b *body) bodyRemains() bool {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	return !b.sawEOF
+}
+
+func (b *body) registerOnHitEOF(fn func()) {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	b.onHitEOF = fn
+}
+
+// bodyLocked is an io.Reader reading from a *body when its mutex is
+// already held.
+type bodyLocked struct {
+	b *body
+}
+
+func (bl bodyLocked) Read(p []byte) (n int, err error) {
+	if bl.b.closed {
+		return 0, ErrBodyReadAfterClose
+	}
+	return bl.b.readLocked(p)
+}
+
+// parseContentLength trims whitespace from s and returns -1 if no value
+// is set, or the value if it's >= 0.
+func parseContentLength(cl string) (int64, error) {
+	cl = textproto.TrimString(cl)
+	if cl == "" {
+		return -1, nil
+	}
+	n, err := strconv.ParseUint(cl, 10, 63)
+	if err != nil {
+		return 0, badStringError("bad Content-Length", cl)
+	}
+	return int64(n), nil
+
+}
+
+// finishAsyncByteRead finishes reading the 1-byte sniff
+// from the ContentLength==0, Body!=nil case.
+type finishAsyncByteRead struct {
+	tw *transferWriter
+}
+
+func (fr finishAsyncByteRead) Read(p []byte) (n int, err error) {
+	if len(p) == 0 {
+		return
+	}
+	rres := <-fr.tw.ByteReadCh
+	n, err = rres.n, rres.err
+	if n == 1 {
+		p[0] = rres.b
+	}
+	if err == nil {
+		err = io.EOF
+	}
+	return
+}
+
+var nopCloserType = reflect.TypeOf(io.NopCloser(nil))
+var nopCloserWriterToType = reflect.TypeOf(io.NopCloser(struct {
+	io.Reader
+	io.WriterTo
+}{}))
+
+// unwrapNopCloser return the underlying reader and true if r is a NopCloser
+// else it return false
+func unwrapNopCloser(r io.Reader) (underlyingReader io.Reader, isNopCloser bool) {
+	switch reflect.TypeOf(r) {
+	case nopCloserType, nopCloserWriterToType:
+		return reflect.ValueOf(r).Field(0).Interface().(io.Reader), true
+	default:
+		return nil, false
+	}
+}
+
+// isKnownInMemoryReader reports whether r is a type known to not
+// block on Read. Its caller uses this as an optional optimization to
+// send fewer TCP packets.
+func isKnownInMemoryReader(r io.Reader) bool {
+	switch r.(type) {
+	case *bytes.Reader, *bytes.Buffer, *strings.Reader:
+		return true
+	}
+	if r, ok := unwrapNopCloser(r); ok {
+		return isKnownInMemoryReader(r)
+	}
+	if r, ok := r.(*readTrackingBody); ok {
+		return isKnownInMemoryReader(r.ReadCloser)
+	}
+	return false
+}
+
+// bufioFlushWriter is an io.Writer wrapper that flushes all writes
+// on its wrapped writer if it's a *bufio.Writer.
+type bufioFlushWriter struct{ w io.Writer }
+
+func (fw bufioFlushWriter) Write(p []byte) (n int, err error) {
+	n, err = fw.w.Write(p)
+	if bw, ok := fw.w.(*bufio.Writer); n > 0 && ok {
+		ferr := bw.Flush()
+		if ferr != nil && err == nil {
+			err = ferr
+		}
+	}
+	return
+}
diff --git a/contrib/go/_std_1.19/src/net/http/transport.go b/contrib/go/_std_1.19/src/net/http/transport.go
new file mode 100644
index 0000000000..e470a6c080
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/http/transport.go
@@ -0,0 +1,2906 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// HTTP client implementation. See RFC 7230 through 7235.
+//
+// This is the low-level Transport implementation of RoundTripper.
+// The high-level interface is in client.go.
+
+package http
+
+import (
+	"bufio"
+	"compress/gzip"
+	"container/list"
+	"context"
+	"crypto/tls"
+	"errors"
+	"fmt"
+	"internal/godebug"
+	"io"
+	"log"
+	"net"
+	"net/http/httptrace"
+	"net/http/internal/ascii"
+	"net/textproto"
+	"net/url"
+	"reflect"
+	"strings"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"golang.org/x/net/http/httpguts"
+	"golang.org/x/net/http/httpproxy"
+)
+
+// DefaultTransport is the default implementation of Transport and is
+// used by DefaultClient. It establishes network connections as needed
+// and caches them for reuse by subsequent calls. It uses HTTP proxies
+// as directed by the $HTTP_PROXY and $NO_PROXY (or $http_proxy and
+// $no_proxy) environment variables.
+var DefaultTransport RoundTripper = &Transport{
+	Proxy: ProxyFromEnvironment,
+	DialContext: defaultTransportDialContext(&net.Dialer{
+		Timeout:   30 * time.Second,
+		KeepAlive: 30 * time.Second,
+	}),
+	ForceAttemptHTTP2:     true,
+	MaxIdleConns:          100,
+	IdleConnTimeout:       90 * time.Second,
+	TLSHandshakeTimeout:   10 * time.Second,
+	ExpectContinueTimeout: 1 * time.Second,
+}
+
+// DefaultMaxIdleConnsPerHost is the default value of Transport's
+// MaxIdleConnsPerHost.
+const DefaultMaxIdleConnsPerHost = 2
+
+// Transport is an implementation of RoundTripper that supports HTTP,
+// HTTPS, and HTTP proxies (for either HTTP or HTTPS with CONNECT).
+//
+// By default, Transport caches connections for future re-use.
+// This may leave many open connections when accessing many hosts.
+// This behavior can be managed using Transport's CloseIdleConnections method
+// and the MaxIdleConnsPerHost and DisableKeepAlives fields.
+//
+// Transports should be reused instead of created as needed.
+// Transports are safe for concurrent use by multiple goroutines.
+//
+// A Transport is a low-level primitive for making HTTP and HTTPS requests.
+// For high-level functionality, such as cookies and redirects, see Client.
+//
+// Transport uses HTTP/1.1 for HTTP URLs and either HTTP/1.1 or HTTP/2
+// for HTTPS URLs, depending on whether the server supports HTTP/2,
+// and how the Transport is configured. The DefaultTransport supports HTTP/2.
+// To explicitly enable HTTP/2 on a transport, use golang.org/x/net/http2
+// and call ConfigureTransport. See the package docs for more about HTTP/2.
+//
+// Responses with status codes in the 1xx range are either handled
+// automatically (100 expect-continue) or ignored. The one
+// exception is HTTP status code 101 (Switching Protocols), which is
+// considered a terminal status and returned by RoundTrip. To see the
+// ignored 1xx responses, use the httptrace trace package's
+// ClientTrace.Got1xxResponse.
+//
+// Transport only retries a request upon encountering a network error
+// if the request is idempotent and either has no body or has its
+// Request.GetBody defined. HTTP requests are considered idempotent if
+// they have HTTP methods GET, HEAD, OPTIONS, or TRACE; or if their
+// Header map contains an "Idempotency-Key" or "X-Idempotency-Key"
+// entry. If the idempotency key value is a zero-length slice, the
+// request is treated as idempotent but the header is not sent on the
+// wire.
+type Transport struct {
+	idleMu       sync.Mutex
+	closeIdle    bool                                // user has requested to close all idle conns
+	idleConn     map[connectMethodKey][]*persistConn // most recently used at end
+	idleConnWait map[connectMethodKey]wantConnQueue  // waiting getConns
+	idleLRU      connLRU
+
+	reqMu       sync.Mutex
+	reqCanceler map[cancelKey]func(error)
+
+	altMu    sync.Mutex   // guards changing altProto only
+	altProto atomic.Value // of nil or map[string]RoundTripper, key is URI scheme
+
+	connsPerHostMu   sync.Mutex
+	connsPerHost     map[connectMethodKey]int
+	connsPerHostWait map[connectMethodKey]wantConnQueue // waiting getConns
+
+	// Proxy specifies a function to return a proxy for a given
+	// Request. If the function returns a non-nil error, the
+	// request is aborted with the provided error.
+	//
+	// The proxy type is determined by the URL scheme. "http",
+	// "https", and "socks5" are supported. If the scheme is empty,
+	// "http" is assumed.
+	//
+	// If Proxy is nil or returns a nil *URL, no proxy is used.
+	Proxy func(*Request) (*url.URL, error)
+
+	// DialContext specifies the dial function for creating unencrypted TCP connections.
+	// If DialContext is nil (and the deprecated Dial below is also nil),
+	// then the transport dials using package net.
+	//
+	// DialContext runs concurrently with calls to RoundTrip.
+	// A RoundTrip call that initiates a dial may end up using
+	// a connection dialed previously when the earlier connection
+	// becomes idle before the later DialContext completes.
+	DialContext func(ctx context.Context, network, addr string) (net.Conn, error)
+
+	// Dial specifies the dial function for creating unencrypted TCP connections.
+	//
+	// Dial runs concurrently with calls to RoundTrip.
+	// A RoundTrip call that initiates a dial may end up using
+	// a connection dialed previously when the earlier connection
+	// becomes idle before the later Dial completes.
+	//
+	// Deprecated: Use DialContext instead, which allows the transport
+	// to cancel dials as soon as they are no longer needed.
+	// If both are set, DialContext takes priority.
+	Dial func(network, addr string) (net.Conn, error)
+
+	// DialTLSContext specifies an optional dial function for creating
+	// TLS connections for non-proxied HTTPS requests.
+	//
+	// If DialTLSContext is nil (and the deprecated DialTLS below is also nil),
+	// DialContext and TLSClientConfig are used.
+	//
+	// If DialTLSContext is set, the Dial and DialContext hooks are not used for HTTPS
+	// requests and the TLSClientConfig and TLSHandshakeTimeout
+	// are ignored. The returned net.Conn is assumed to already be
+	// past the TLS handshake.
+	DialTLSContext func(ctx context.Context, network, addr string) (net.Conn, error)
+
+	// DialTLS specifies an optional dial function for creating
+	// TLS connections for non-proxied HTTPS requests.
+	//
+	// Deprecated: Use DialTLSContext instead, which allows the transport
+	// to cancel dials as soon as they are no longer needed.
+	// If both are set, DialTLSContext takes priority.
+	DialTLS func(network, addr string) (net.Conn, error)
+
+	// TLSClientConfig specifies the TLS configuration to use with
+	// tls.Client.
+	// If nil, the default configuration is used.
+	// If non-nil, HTTP/2 support may not be enabled by default.
+	TLSClientConfig *tls.Config
+
+	// TLSHandshakeTimeout specifies the maximum amount of time waiting to
+	// wait for a TLS handshake. Zero means no timeout.
+	TLSHandshakeTimeout time.Duration
+
+	// DisableKeepAlives, if true, disables HTTP keep-alives and
+	// will only use the connection to the server for a single
+	// HTTP request.
+	//
+	// This is unrelated to the similarly named TCP keep-alives.
+	DisableKeepAlives bool
+
+	// DisableCompression, if true, prevents the Transport from
+	// requesting compression with an "Accept-Encoding: gzip"
+	// request header when the Request contains no existing
+	// Accept-Encoding value. If the Transport requests gzip on
+	// its own and gets a gzipped response, it's transparently
+	// decoded in the Response.Body. However, if the user
+	// explicitly requested gzip it is not automatically
+	// uncompressed.
+	DisableCompression bool
+
+	// MaxIdleConns controls the maximum number of idle (keep-alive)
+	// connections across all hosts. Zero means no limit.
+	MaxIdleConns int
+
+	// MaxIdleConnsPerHost, if non-zero, controls the maximum idle
+	// (keep-alive) connections to keep per-host. If zero,
+	// DefaultMaxIdleConnsPerHost is used.
+	MaxIdleConnsPerHost int
+
+	// MaxConnsPerHost optionally limits the total number of
+	// connections per host, including connections in the dialing,
+	// active, and idle states. On limit violation, dials will block.
+	//
+	// Zero means no limit.
+	MaxConnsPerHost int
+
+	// IdleConnTimeout is the maximum amount of time an idle
+	// (keep-alive) connection will remain idle before closing
+	// itself.
+	// Zero means no limit.
+	IdleConnTimeout time.Duration
+
+	// ResponseHeaderTimeout, if non-zero, specifies the amount of
+	// time to wait for a server's response headers after fully
+	// writing the request (including its body, if any). This
+	// time does not include the time to read the response body.
+	ResponseHeaderTimeout time.Duration
+
+	// ExpectContinueTimeout, if non-zero, specifies the amount of
+	// time to wait for a server's first response headers after fully
+	// writing the request headers if the request has an
+	// "Expect: 100-continue" header. Zero means no timeout and
+	// causes the body to be sent immediately, without
+	// waiting for the server to approve.
+	// This time does not include the time to send the request header.
+	ExpectContinueTimeout time.Duration
+
+	// TLSNextProto specifies how the Transport switches to an
+	// alternate protocol (such as HTTP/2) after a TLS ALPN
+	// protocol negotiation. If Transport dials an TLS connection
+	// with a non-empty protocol name and TLSNextProto contains a
+	// map entry for that key (such as "h2"), then the func is
+	// called with the request's authority (such as "example.com"
+	// or "example.com:1234") and the TLS connection. The function
+	// must return a RoundTripper that then handles the request.
+	// If TLSNextProto is not nil, HTTP/2 support is not enabled
+	// automatically.
+	TLSNextProto map[string]func(authority string, c *tls.Conn) RoundTripper
+
+	// ProxyConnectHeader optionally specifies headers to send to
+	// proxies during CONNECT requests.
+	// To set the header dynamically, see GetProxyConnectHeader.
+	ProxyConnectHeader Header
+
+	// GetProxyConnectHeader optionally specifies a func to return
+	// headers to send to proxyURL during a CONNECT request to the
+	// ip:port target.
+	// If it returns an error, the Transport's RoundTrip fails with
+	// that error. It can return (nil, nil) to not add headers.
+	// If GetProxyConnectHeader is non-nil, ProxyConnectHeader is
+	// ignored.
+	GetProxyConnectHeader func(ctx context.Context, proxyURL *url.URL, target string) (Header, error)
+
+	// MaxResponseHeaderBytes specifies a limit on how many
+	// response bytes are allowed in the server's response
+	// header.
+	//
+	// Zero means to use a default limit.
+	MaxResponseHeaderBytes int64
+
+	// WriteBufferSize specifies the size of the write buffer used
+	// when writing to the transport.
+	// If zero, a default (currently 4KB) is used.
+	WriteBufferSize int
+
+	// ReadBufferSize specifies the size of the read buffer used
+	// when reading from the transport.
+	// If zero, a default (currently 4KB) is used.
+	ReadBufferSize int
+
+	// nextProtoOnce guards initialization of TLSNextProto and
+	// h2transport (via onceSetNextProtoDefaults)
+	nextProtoOnce      sync.Once
+	h2transport        h2Transport // non-nil if http2 wired up
+	tlsNextProtoWasNil bool        // whether TLSNextProto was nil when the Once fired
+
+	// ForceAttemptHTTP2 controls whether HTTP/2 is enabled when a non-zero
+	// Dial, DialTLS, or DialContext func or TLSClientConfig is provided.
+	// By default, use of any those fields conservatively disables HTTP/2.
+	// To use a custom dialer or TLS config and still attempt HTTP/2
+	// upgrades, set this to true.
+	ForceAttemptHTTP2 bool
+}
+
+// A cancelKey is the key of the reqCanceler map.
+// We wrap the *Request in this type since we want to use the original request,
+// not any transient one created by roundTrip.
+type cancelKey struct {
+	req *Request
+}
+
+func (t *Transport) writeBufferSize() int {
+	if t.WriteBufferSize > 0 {
+		return t.WriteBufferSize
+	}
+	return 4 << 10
+}
+
+func (t *Transport) readBufferSize() int {
+	if t.ReadBufferSize > 0 {
+		return t.ReadBufferSize
+	}
+	return 4 << 10
+}
+
+// Clone returns a deep copy of t's exported fields.
+func (t *Transport) Clone() *Transport {
+	t.nextProtoOnce.Do(t.onceSetNextProtoDefaults)
+	t2 := &Transport{
+		Proxy:                  t.Proxy,
+		DialContext:            t.DialContext,
+		Dial:                   t.Dial,
+		DialTLS:                t.DialTLS,
+		DialTLSContext:         t.DialTLSContext,
+		TLSHandshakeTimeout:    t.TLSHandshakeTimeout,
+		DisableKeepAlives:      t.DisableKeepAlives,
+		DisableCompression:     t.DisableCompression,
+		MaxIdleConns:           t.MaxIdleConns,
+		MaxIdleConnsPerHost:    t.MaxIdleConnsPerHost,
+		MaxConnsPerHost:        t.MaxConnsPerHost,
+		IdleConnTimeout:        t.IdleConnTimeout,
+		ResponseHeaderTimeout:  t.ResponseHeaderTimeout,
+		ExpectContinueTimeout:  t.ExpectContinueTimeout,
+		ProxyConnectHeader:     t.ProxyConnectHeader.Clone(),
+		GetProxyConnectHeader:  t.GetProxyConnectHeader,
+		MaxResponseHeaderBytes: t.MaxResponseHeaderBytes,
+		ForceAttemptHTTP2:      t.ForceAttemptHTTP2,
+		WriteBufferSize:        t.WriteBufferSize,
+		ReadBufferSize:         t.ReadBufferSize,
+	}
+	if t.TLSClientConfig != nil {
+		t2.TLSClientConfig = t.TLSClientConfig.Clone()
+	}
+	if !t.tlsNextProtoWasNil {
+		npm := map[string]func(authority string, c *tls.Conn) RoundTripper{}
+		for k, v := range t.TLSNextProto {
+			npm[k] = v
+		}
+		t2.TLSNextProto = npm
+	}
+	return t2
+}
+
+// h2Transport is the interface we expect to be able to call from
+// net/http against an *http2.Transport that's either bundled into
+// h2_bundle.go or supplied by the user via x/net/http2.
+//
+// We name it with the "h2" prefix to stay out of the "http2" prefix
+// namespace used by x/tools/cmd/bundle for h2_bundle.go.
+type h2Transport interface {
+	CloseIdleConnections()
+}
+
+func (t *Transport) hasCustomTLSDialer() bool {
+	return t.DialTLS != nil || t.DialTLSContext != nil
+}
+
+// onceSetNextProtoDefaults initializes TLSNextProto.
+// It must be called via t.nextProtoOnce.Do.
+func (t *Transport) onceSetNextProtoDefaults() {
+	t.tlsNextProtoWasNil = (t.TLSNextProto == nil)
+	if godebug.Get("http2client") == "0" {
+		return
+	}
+
+	// If they've already configured http2 with
+	// golang.org/x/net/http2 instead of the bundled copy, try to
+	// get at its http2.Transport value (via the "https"
+	// altproto map) so we can call CloseIdleConnections on it if
+	// requested. (Issue 22891)
+	altProto, _ := t.altProto.Load().(map[string]RoundTripper)
+	if rv := reflect.ValueOf(altProto["https"]); rv.IsValid() && rv.Type().Kind() == reflect.Struct && rv.Type().NumField() == 1 {
+		if v := rv.Field(0); v.CanInterface() {
+			if h2i, ok := v.Interface().(h2Transport); ok {
+				t.h2transport = h2i
+				return
+			}
+		}
+	}
+
+	if t.TLSNextProto != nil {
+		// This is the documented way to disable http2 on a
+		// Transport.
+		return
+	}
+	if !t.ForceAttemptHTTP2 && (t.TLSClientConfig != nil || t.Dial != nil || t.DialContext != nil || t.hasCustomTLSDialer()) {
+		// Be conservative and don't automatically enable
+		// http2 if they've specified a custom TLS config or
+		// custom dialers. Let them opt-in themselves via
+		// http2.ConfigureTransport so we don't surprise them
+		// by modifying their tls.Config. Issue 14275.
+		// However, if ForceAttemptHTTP2 is true, it overrides the above checks.
+		return
+	}
+	if omitBundledHTTP2 {
+		return
+	}
+	t2, err := http2configureTransports(t)
+	if err != nil {
+		log.Printf("Error enabling Transport HTTP/2 support: %v", err)
+		return
+	}
+	t.h2transport = t2
+
+	// Auto-configure the http2.Transport's MaxHeaderListSize from
+	// the http.Transport's MaxResponseHeaderBytes. They don't
+	// exactly mean the same thing, but they're close.
+	//
+	// TODO: also add this to x/net/http2.Configure Transport, behind
+	// a +build go1.7 build tag:
+	if limit1 := t.MaxResponseHeaderBytes; limit1 != 0 && t2.MaxHeaderListSize == 0 {
+		const h2max = 1<<32 - 1
+		if limit1 >= h2max {
+			t2.MaxHeaderListSize = h2max
+		} else {
+			t2.MaxHeaderListSize = uint32(limit1)
+		}
+	}
+}
+
+// ProxyFromEnvironment returns the URL of the proxy to use for a
+// given request, as indicated by the environment variables
+// HTTP_PROXY, HTTPS_PROXY and NO_PROXY (or the lowercase versions
+// thereof). HTTPS_PROXY takes precedence over HTTP_PROXY for https
+// requests.
+//
+// The environment values may be either a complete URL or a
+// "host[:port]", in which case the "http" scheme is assumed.
+// The schemes "http", "https", and "socks5" are supported.
+// An error is returned if the value is a different form.
+//
+// A nil URL and nil error are returned if no proxy is defined in the
+// environment, or a proxy should not be used for the given request,
+// as defined by NO_PROXY.
+//
+// As a special case, if req.URL.Host is "localhost" (with or without
+// a port number), then a nil URL and nil error will be returned.
+func ProxyFromEnvironment(req *Request) (*url.URL, error) {
+	return envProxyFunc()(req.URL)
+}
+
+// ProxyURL returns a proxy function (for use in a Transport)
+// that always returns the same URL.
+func ProxyURL(fixedURL *url.URL) func(*Request) (*url.URL, error) {
+	return func(*Request) (*url.URL, error) {
+		return fixedURL, nil
+	}
+}
+
+// transportRequest is a wrapper around a *Request that adds
+// optional extra headers to write and stores any error to return
+// from roundTrip.
+type transportRequest struct {
+	*Request                         // original request, not to be mutated
+	extra     Header                 // extra headers to write, or nil
+	trace     *httptrace.ClientTrace // optional
+	cancelKey cancelKey
+
+	mu  sync.Mutex // guards err
+	err error      // first setError value for mapRoundTripError to consider
+}
+
+func (tr *transportRequest) extraHeaders() Header {
+	if tr.extra == nil {
+		tr.extra = make(Header)
+	}
+	return tr.extra
+}
+
+func (tr *transportRequest) setError(err error) {
+	tr.mu.Lock()
+	if tr.err == nil {
+		tr.err = err
+	}
+	tr.mu.Unlock()
+}
+
+// useRegisteredProtocol reports whether an alternate protocol (as registered
+// with Transport.RegisterProtocol) should be respected for this request.
+func (t *Transport) useRegisteredProtocol(req *Request) bool {
+	if req.URL.Scheme == "https" && req.requiresHTTP1() {
+		// If this request requires HTTP/1, don't use the
+		// "https" alternate protocol, which is used by the
+		// HTTP/2 code to take over requests if there's an
+		// existing cached HTTP/2 connection.
+		return false
+	}
+	return true
+}
+
+// alternateRoundTripper returns the alternate RoundTripper to use
+// for this request if the Request's URL scheme requires one,
+// or nil for the normal case of using the Transport.
+func (t *Transport) alternateRoundTripper(req *Request) RoundTripper {
+	if !t.useRegisteredProtocol(req) {
+		return nil
+	}
+	altProto, _ := t.altProto.Load().(map[string]RoundTripper)
+	return altProto[req.URL.Scheme]
+}
+
+// roundTrip implements a RoundTripper over HTTP.
+func (t *Transport) roundTrip(req *Request) (*Response, error) {
+	t.nextProtoOnce.Do(t.onceSetNextProtoDefaults)
+	ctx := req.Context()
+	trace := httptrace.ContextClientTrace(ctx)
+
+	if req.URL == nil {
+		req.closeBody()
+		return nil, errors.New("http: nil Request.URL")
+	}
+	if req.Header == nil {
+		req.closeBody()
+		return nil, errors.New("http: nil Request.Header")
+	}
+	scheme := req.URL.Scheme
+	isHTTP := scheme == "http" || scheme == "https"
+	if isHTTP {
+		for k, vv := range req.Header {
+			if !httpguts.ValidHeaderFieldName(k) {
+				req.closeBody()
+				return nil, fmt.Errorf("net/http: invalid header field name %q", k)
+			}
+			for _, v := range vv {
+				if !httpguts.ValidHeaderFieldValue(v) {
+					req.closeBody()
+					// Don't include the value in the error, because it may be sensitive.
+					return nil, fmt.Errorf("net/http: invalid header field value for %q", k)
+				}
+			}
+		}
+	}
+
+	origReq := req
+	cancelKey := cancelKey{origReq}
+	req = setupRewindBody(req)
+
+	if altRT := t.alternateRoundTripper(req); altRT != nil {
+		if resp, err := altRT.RoundTrip(req); err != ErrSkipAltProtocol {
+			return resp, err
+		}
+		var err error
+		req, err = rewindBody(req)
+		if err != nil {
+			return nil, err
+		}
+	}
+	if !isHTTP {
+		req.closeBody()
+		return nil, badStringError("unsupported protocol scheme", scheme)
+	}
+	if req.Method != "" && !validMethod(req.Method) {
+		req.closeBody()
+		return nil, fmt.Errorf("net/http: invalid method %q", req.Method)
+	}
+	if req.URL.Host == "" {
+		req.closeBody()
+		return nil, errors.New("http: no Host in request URL")
+	}
+
+	for {
+		select {
+		case <-ctx.Done():
+			req.closeBody()
+			return nil, ctx.Err()
+		default:
+		}
+
+		// treq gets modified by roundTrip, so we need to recreate for each retry.
+		treq := &transportRequest{Request: req, trace: trace, cancelKey: cancelKey}
+		cm, err := t.connectMethodForRequest(treq)
+		if err != nil {
+			req.closeBody()
+			return nil, err
+		}
+
+		// Get the cached or newly-created connection to either the
+		// host (for http or https), the http proxy, or the http proxy
+		// pre-CONNECTed to https server. In any case, we'll be ready
+		// to send it requests.
+		pconn, err := t.getConn(treq, cm)
+		if err != nil {
+			t.setReqCanceler(cancelKey, nil)
+			req.closeBody()
+			return nil, err
+		}
+
+		var resp *Response
+		if pconn.alt != nil {
+			// HTTP/2 path.
+			t.setReqCanceler(cancelKey, nil) // not cancelable with CancelRequest
+			resp, err = pconn.alt.RoundTrip(req)
+		} else {
+			resp, err = pconn.roundTrip(treq)
+		}
+		if err == nil {
+			resp.Request = origReq
+			return resp, nil
+		}
+
+		// Failed. Clean up and determine whether to retry.
+		if http2isNoCachedConnError(err) {
+			if t.removeIdleConn(pconn) {
+				t.decConnsPerHost(pconn.cacheKey)
+			}
+		} else if !pconn.shouldRetryRequest(req, err) {
+			// Issue 16465: return underlying net.Conn.Read error from peek,
+			// as we've historically done.
+			if e, ok := err.(nothingWrittenError); ok {
+				err = e.error
+			}
+			if e, ok := err.(transportReadFromServerError); ok {
+				err = e.err
+			}
+			return nil, err
+		}
+		testHookRoundTripRetried()
+
+		// Rewind the body if we're able to.
+		req, err = rewindBody(req)
+		if err != nil {
+			return nil, err
+		}
+	}
+}
+
+var errCannotRewind = errors.New("net/http: cannot rewind body after connection loss")
+
+type readTrackingBody struct {
+	io.ReadCloser
+	didRead  bool
+	didClose bool
+}
+
+func (r *readTrackingBody) Read(data []byte) (int, error) {
+	r.didRead = true
+	return r.ReadCloser.Read(data)
+}
+
+func (r *readTrackingBody) Close() error {
+	r.didClose = true
+	return r.ReadCloser.Close()
+}
+
+// setupRewindBody returns a new request with a custom body wrapper
+// that can report whether the body needs rewinding.
+// This lets rewindBody avoid an error result when the request
+// does not have GetBody but the body hasn't been read at all yet.
+func setupRewindBody(req *Request) *Request {
+	if req.Body == nil || req.Body == NoBody {
+		return req
+	}
+	newReq := *req
+	newReq.Body = &readTrackingBody{ReadCloser: req.Body}
+	return &newReq
+}
+
+// rewindBody returns a new request with the body rewound.
+// It returns req unmodified if the body does not need rewinding.
+// rewindBody takes care of closing req.Body when appropriate
+// (in all cases except when rewindBody returns req unmodified).
+func rewindBody(req *Request) (rewound *Request, err error) {
+	if req.Body == nil || req.Body == NoBody || (!req.Body.(*readTrackingBody).didRead && !req.Body.(*readTrackingBody).didClose) {
+		return req, nil // nothing to rewind
+	}
+	if !req.Body.(*readTrackingBody).didClose {
+		req.closeBody()
+	}
+	if req.GetBody == nil {
+		return nil, errCannotRewind
+	}
+	body, err := req.GetBody()
+	if err != nil {
+		return nil, err
+	}
+	newReq := *req
+	newReq.Body = &readTrackingBody{ReadCloser: body}
+	return &newReq, nil
+}
+
+// shouldRetryRequest reports whether we should retry sending a failed
+// HTTP request on a new connection. The non-nil input error is the
+// error from roundTrip.
+func (pc *persistConn) shouldRetryRequest(req *Request, err error) bool {
+	if http2isNoCachedConnError(err) {
+		// Issue 16582: if the user started a bunch of
+		// requests at once, they can all pick the same conn
+		// and violate the server's max concurrent streams.
+		// Instead, match the HTTP/1 behavior for now and dial
+		// again to get a new TCP connection, rather than failing
+		// this request.
+		return true
+	}
+	if err == errMissingHost {
+		// User error.
+		return false
+	}
+	if !pc.isReused() {
+		// This was a fresh connection. There's no reason the server
+		// should've hung up on us.
+		//
+		// Also, if we retried now, we could loop forever
+		// creating new connections and retrying if the server
+		// is just hanging up on us because it doesn't like
+		// our request (as opposed to sending an error).
+		return false
+	}
+	if _, ok := err.(nothingWrittenError); ok {
+		// We never wrote anything, so it's safe to retry, if there's no body or we
+		// can "rewind" the body with GetBody.
+		return req.outgoingLength() == 0 || req.GetBody != nil
+	}
+	if !req.isReplayable() {
+		// Don't retry non-idempotent requests.
+		return false
+	}
+	if _, ok := err.(transportReadFromServerError); ok {
+		// We got some non-EOF net.Conn.Read failure reading
+		// the 1st response byte from the server.
+		return true
+	}
+	if err == errServerClosedIdle {
+		// The server replied with io.EOF while we were trying to
+		// read the response. Probably an unfortunately keep-alive
+		// timeout, just as the client was writing a request.
+		return true
+	}
+	return false // conservatively
+}
+
+// ErrSkipAltProtocol is a sentinel error value defined by Transport.RegisterProtocol.
+var ErrSkipAltProtocol = errors.New("net/http: skip alternate protocol")
+
+// RegisterProtocol registers a new protocol with scheme.
+// The Transport will pass requests using the given scheme to rt.
+// It is rt's responsibility to simulate HTTP request semantics.
+//
+// RegisterProtocol can be used by other packages to provide
+// implementations of protocol schemes like "ftp" or "file".
+//
+// If rt.RoundTrip returns ErrSkipAltProtocol, the Transport will
+// handle the RoundTrip itself for that one request, as if the
+// protocol were not registered.
+func (t *Transport) RegisterProtocol(scheme string, rt RoundTripper) {
+	t.altMu.Lock()
+	defer t.altMu.Unlock()
+	oldMap, _ := t.altProto.Load().(map[string]RoundTripper)
+	if _, exists := oldMap[scheme]; exists {
+		panic("protocol " + scheme + " already registered")
+	}
+	newMap := make(map[string]RoundTripper)
+	for k, v := range oldMap {
+		newMap[k] = v
+	}
+	newMap[scheme] = rt
+	t.altProto.Store(newMap)
+}
+
+// CloseIdleConnections closes any connections which were previously
+// connected from previous requests but are now sitting idle in
+// a "keep-alive" state. It does not interrupt any connections currently
+// in use.
+func (t *Transport) CloseIdleConnections() {
+	t.nextProtoOnce.Do(t.onceSetNextProtoDefaults)
+	t.idleMu.Lock()
+	m := t.idleConn
+	t.idleConn = nil
+	t.closeIdle = true // close newly idle connections
+	t.idleLRU = connLRU{}
+	t.idleMu.Unlock()
+	for _, conns := range m {
+		for _, pconn := range conns {
+			pconn.close(errCloseIdleConns)
+		}
+	}
+	if t2 := t.h2transport; t2 != nil {
+		t2.CloseIdleConnections()
+	}
+}
+
+// CancelRequest cancels an in-flight request by closing its connection.
+// CancelRequest should only be called after RoundTrip has returned.
+//
+// Deprecated: Use Request.WithContext to create a request with a
+// cancelable context instead. CancelRequest cannot cancel HTTP/2
+// requests.
+func (t *Transport) CancelRequest(req *Request) {
+	t.cancelRequest(cancelKey{req}, errRequestCanceled)
+}
+
+// Cancel an in-flight request, recording the error value.
+// Returns whether the request was canceled.
+func (t *Transport) cancelRequest(key cancelKey, err error) bool {
+	// This function must not return until the cancel func has completed.
+	// See: https://golang.org/issue/34658
+	t.reqMu.Lock()
+	defer t.reqMu.Unlock()
+	cancel := t.reqCanceler[key]
+	delete(t.reqCanceler, key)
+	if cancel != nil {
+		cancel(err)
+	}
+
+	return cancel != nil
+}
+
+//
+// Private implementation past this point.
+//
+
+var (
+	// proxyConfigOnce guards proxyConfig
+	envProxyOnce      sync.Once
+	envProxyFuncValue func(*url.URL) (*url.URL, error)
+)
+
+// defaultProxyConfig returns a ProxyConfig value looked up
+// from the environment. This mitigates expensive lookups
+// on some platforms (e.g. Windows).
+func envProxyFunc() func(*url.URL) (*url.URL, error) {
+	envProxyOnce.Do(func() {
+		envProxyFuncValue = httpproxy.FromEnvironment().ProxyFunc()
+	})
+	return envProxyFuncValue
+}
+
+// resetProxyConfig is used by tests.
+func resetProxyConfig() {
+	envProxyOnce = sync.Once{}
+	envProxyFuncValue = nil
+}
+
+func (t *Transport) connectMethodForRequest(treq *transportRequest) (cm connectMethod, err error) {
+	cm.targetScheme = treq.URL.Scheme
+	cm.targetAddr = canonicalAddr(treq.URL)
+	if t.Proxy != nil {
+		cm.proxyURL, err = t.Proxy(treq.Request)
+	}
+	cm.onlyH1 = treq.requiresHTTP1()
+	return cm, err
+}
+
+// proxyAuth returns the Proxy-Authorization header to set
+// on requests, if applicable.
+func (cm *connectMethod) proxyAuth() string {
+	if cm.proxyURL == nil {
+		return ""
+	}
+	if u := cm.proxyURL.User; u != nil {
+		username := u.Username()
+		password, _ := u.Password()
+		return "Basic " + basicAuth(username, password)
+	}
+	return ""
+}
+
+// error values for debugging and testing, not seen by users.
+var (
+	errKeepAlivesDisabled = errors.New("http: putIdleConn: keep alives disabled")
+	errConnBroken         = errors.New("http: putIdleConn: connection is in bad state")
+	errCloseIdle          = errors.New("http: putIdleConn: CloseIdleConnections was called")
+	errTooManyIdle        = errors.New("http: putIdleConn: too many idle connections")
+	errTooManyIdleHost    = errors.New("http: putIdleConn: too many idle connections for host")
+	errCloseIdleConns     = errors.New("http: CloseIdleConnections called")
+	errReadLoopExiting    = errors.New("http: persistConn.readLoop exiting")
+	errIdleConnTimeout    = errors.New("http: idle connection timeout")
+
+	// errServerClosedIdle is not seen by users for idempotent requests, but may be
+	// seen by a user if the server shuts down an idle connection and sends its FIN
+	// in flight with already-written POST body bytes from the client.
+	// See https://github.com/golang/go/issues/19943#issuecomment-355607646
+	errServerClosedIdle = errors.New("http: server closed idle connection")
+)
+
+// transportReadFromServerError is used by Transport.readLoop when the
+// 1 byte peek read fails and we're actually anticipating a response.
+// Usually this is just due to the inherent keep-alive shut down race,
+// where the server closed the connection at the same time the client
+// wrote. The underlying err field is usually io.EOF or some
+// ECONNRESET sort of thing which varies by platform. But it might be
+// the user's custom net.Conn.Read error too, so we carry it along for
+// them to return from Transport.RoundTrip.
+type transportReadFromServerError struct {
+	err error
+}
+
+func (e transportReadFromServerError) Unwrap() error { return e.err }
+
+func (e transportReadFromServerError) Error() string {
+	return fmt.Sprintf("net/http: Transport failed to read from server: %v", e.err)
+}
+
+func (t *Transport) putOrCloseIdleConn(pconn *persistConn) {
+	if err := t.tryPutIdleConn(pconn); err != nil {
+		pconn.close(err)
+	}
+}
+
+func (t *Transport) maxIdleConnsPerHost() int {
+	if v := t.MaxIdleConnsPerHost; v != 0 {
+		return v
+	}
+	return DefaultMaxIdleConnsPerHost
+}
+
+// tryPutIdleConn adds pconn to the list of idle persistent connections awaiting
+// a new request.
+// If pconn is no longer needed or not in a good state, tryPutIdleConn returns
+// an error explaining why it wasn't registered.
+// tryPutIdleConn does not close pconn. Use putOrCloseIdleConn instead for that.
+func (t *Transport) tryPutIdleConn(pconn *persistConn) error {
+	if t.DisableKeepAlives || t.MaxIdleConnsPerHost < 0 {
+		return errKeepAlivesDisabled
+	}
+	if pconn.isBroken() {
+		return errConnBroken
+	}
+	pconn.markReused()
+
+	t.idleMu.Lock()
+	defer t.idleMu.Unlock()
+
+	// HTTP/2 (pconn.alt != nil) connections do not come out of the idle list,
+	// because multiple goroutines can use them simultaneously.
+	// If this is an HTTP/2 connection being “returned,” we're done.
+	if pconn.alt != nil && t.idleLRU.m[pconn] != nil {
+		return nil
+	}
+
+	// Deliver pconn to goroutine waiting for idle connection, if any.
+	// (They may be actively dialing, but this conn is ready first.
+	// Chrome calls this socket late binding.
+	// See https://www.chromium.org/developers/design-documents/network-stack#TOC-Connection-Management.)
+	key := pconn.cacheKey
+	if q, ok := t.idleConnWait[key]; ok {
+		done := false
+		if pconn.alt == nil {
+			// HTTP/1.
+			// Loop over the waiting list until we find a w that isn't done already, and hand it pconn.
+			for q.len() > 0 {
+				w := q.popFront()
+				if w.tryDeliver(pconn, nil) {
+					done = true
+					break
+				}
+			}
+		} else {
+			// HTTP/2.
+			// Can hand the same pconn to everyone in the waiting list,
+			// and we still won't be done: we want to put it in the idle
+			// list unconditionally, for any future clients too.
+			for q.len() > 0 {
+				w := q.popFront()
+				w.tryDeliver(pconn, nil)
+			}
+		}
+		if q.len() == 0 {
+			delete(t.idleConnWait, key)
+		} else {
+			t.idleConnWait[key] = q
+		}
+		if done {
+			return nil
+		}
+	}
+
+	if t.closeIdle {
+		return errCloseIdle
+	}
+	if t.idleConn == nil {
+		t.idleConn = make(map[connectMethodKey][]*persistConn)
+	}
+	idles := t.idleConn[key]
+	if len(idles) >= t.maxIdleConnsPerHost() {
+		return errTooManyIdleHost
+	}
+	for _, exist := range idles {
+		if exist == pconn {
+			log.Fatalf("dup idle pconn %p in freelist", pconn)
+		}
+	}
+	t.idleConn[key] = append(idles, pconn)
+	t.idleLRU.add(pconn)
+	if t.MaxIdleConns != 0 && t.idleLRU.len() > t.MaxIdleConns {
+		oldest := t.idleLRU.removeOldest()
+		oldest.close(errTooManyIdle)
+		t.removeIdleConnLocked(oldest)
+	}
+
+	// Set idle timer, but only for HTTP/1 (pconn.alt == nil).
+	// The HTTP/2 implementation manages the idle timer itself
+	// (see idleConnTimeout in h2_bundle.go).
+	if t.IdleConnTimeout > 0 && pconn.alt == nil {
+		if pconn.idleTimer != nil {
+			pconn.idleTimer.Reset(t.IdleConnTimeout)
+		} else {
+			pconn.idleTimer = time.AfterFunc(t.IdleConnTimeout, pconn.closeConnIfStillIdle)
+		}
+	}
+	pconn.idleAt = time.Now()
+	return nil
+}
+
+// queueForIdleConn queues w to receive the next idle connection for w.cm.
+// As an optimization hint to the caller, queueForIdleConn reports whether
+// it successfully delivered an already-idle connection.
+func (t *Transport) queueForIdleConn(w *wantConn) (delivered bool) {
+	if t.DisableKeepAlives {
+		return false
+	}
+
+	t.idleMu.Lock()
+	defer t.idleMu.Unlock()
+
+	// Stop closing connections that become idle - we might want one.
+	// (That is, undo the effect of t.CloseIdleConnections.)
+	t.closeIdle = false
+
+	if w == nil {
+		// Happens in test hook.
+		return false
+	}
+
+	// If IdleConnTimeout is set, calculate the oldest
+	// persistConn.idleAt time we're willing to use a cached idle
+	// conn.
+	var oldTime time.Time
+	if t.IdleConnTimeout > 0 {
+		oldTime = time.Now().Add(-t.IdleConnTimeout)
+	}
+
+	// Look for most recently-used idle connection.
+	if list, ok := t.idleConn[w.key]; ok {
+		stop := false
+		delivered := false
+		for len(list) > 0 && !stop {
+			pconn := list[len(list)-1]
+
+			// See whether this connection has been idle too long, considering
+			// only the wall time (the Round(0)), in case this is a laptop or VM
+			// coming out of suspend with previously cached idle connections.
+			tooOld := !oldTime.IsZero() && pconn.idleAt.Round(0).Before(oldTime)
+			if tooOld {
+				// Async cleanup. Launch in its own goroutine (as if a
+				// time.AfterFunc called it); it acquires idleMu, which we're
+				// holding, and does a synchronous net.Conn.Close.
+				go pconn.closeConnIfStillIdle()
+			}
+			if pconn.isBroken() || tooOld {
+				// If either persistConn.readLoop has marked the connection
+				// broken, but Transport.removeIdleConn has not yet removed it
+				// from the idle list, or if this persistConn is too old (it was
+				// idle too long), then ignore it and look for another. In both
+				// cases it's already in the process of being closed.
+				list = list[:len(list)-1]
+				continue
+			}
+			delivered = w.tryDeliver(pconn, nil)
+			if delivered {
+				if pconn.alt != nil {
+					// HTTP/2: multiple clients can share pconn.
+					// Leave it in the list.
+				} else {
+					// HTTP/1: only one client can use pconn.
+					// Remove it from the list.
+					t.idleLRU.remove(pconn)
+					list = list[:len(list)-1]
+				}
+			}
+			stop = true
+		}
+		if len(list) > 0 {
+			t.idleConn[w.key] = list
+		} else {
+			delete(t.idleConn, w.key)
+		}
+		if stop {
+			return delivered
+		}
+	}
+
+	// Register to receive next connection that becomes idle.
+	if t.idleConnWait == nil {
+		t.idleConnWait = make(map[connectMethodKey]wantConnQueue)
+	}
+	q := t.idleConnWait[w.key]
+	q.cleanFront()
+	q.pushBack(w)
+	t.idleConnWait[w.key] = q
+	return false
+}
+
+// removeIdleConn marks pconn as dead.
+func (t *Transport) removeIdleConn(pconn *persistConn) bool {
+	t.idleMu.Lock()
+	defer t.idleMu.Unlock()
+	return t.removeIdleConnLocked(pconn)
+}
+
+// t.idleMu must be held.
+func (t *Transport) removeIdleConnLocked(pconn *persistConn) bool {
+	if pconn.idleTimer != nil {
+		pconn.idleTimer.Stop()
+	}
+	t.idleLRU.remove(pconn)
+	key := pconn.cacheKey
+	pconns := t.idleConn[key]
+	var removed bool
+	switch len(pconns) {
+	case 0:
+		// Nothing
+	case 1:
+		if pconns[0] == pconn {
+			delete(t.idleConn, key)
+			removed = true
+		}
+	default:
+		for i, v := range pconns {
+			if v != pconn {
+				continue
+			}
+			// Slide down, keeping most recently-used
+			// conns at the end.
+			copy(pconns[i:], pconns[i+1:])
+			t.idleConn[key] = pconns[:len(pconns)-1]
+			removed = true
+			break
+		}
+	}
+	return removed
+}
+
+func (t *Transport) setReqCanceler(key cancelKey, fn func(error)) {
+	t.reqMu.Lock()
+	defer t.reqMu.Unlock()
+	if t.reqCanceler == nil {
+		t.reqCanceler = make(map[cancelKey]func(error))
+	}
+	if fn != nil {
+		t.reqCanceler[key] = fn
+	} else {
+		delete(t.reqCanceler, key)
+	}
+}
+
+// replaceReqCanceler replaces an existing cancel function. If there is no cancel function
+// for the request, we don't set the function and return false.
+// Since CancelRequest will clear the canceler, we can use the return value to detect if
+// the request was canceled since the last setReqCancel call.
+func (t *Transport) replaceReqCanceler(key cancelKey, fn func(error)) bool {
+	t.reqMu.Lock()
+	defer t.reqMu.Unlock()
+	_, ok := t.reqCanceler[key]
+	if !ok {
+		return false
+	}
+	if fn != nil {
+		t.reqCanceler[key] = fn
+	} else {
+		delete(t.reqCanceler, key)
+	}
+	return true
+}
+
+var zeroDialer net.Dialer
+
+func (t *Transport) dial(ctx context.Context, network, addr string) (net.Conn, error) {
+	if t.DialContext != nil {
+		return t.DialContext(ctx, network, addr)
+	}
+	if t.Dial != nil {
+		c, err := t.Dial(network, addr)
+		if c == nil && err == nil {
+			err = errors.New("net/http: Transport.Dial hook returned (nil, nil)")
+		}
+		return c, err
+	}
+	return zeroDialer.DialContext(ctx, network, addr)
+}
+
+// A wantConn records state about a wanted connection
+// (that is, an active call to getConn).
+// The conn may be gotten by dialing or by finding an idle connection,
+// or a cancellation may make the conn no longer wanted.
+// These three options are racing against each other and use
+// wantConn to coordinate and agree about the winning outcome.
+type wantConn struct {
+	cm    connectMethod
+	key   connectMethodKey // cm.key()
+	ctx   context.Context  // context for dial
+	ready chan struct{}    // closed when pc, err pair is delivered
+
+	// hooks for testing to know when dials are done
+	// beforeDial is called in the getConn goroutine when the dial is queued.
+	// afterDial is called when the dial is completed or canceled.
+	beforeDial func()
+	afterDial  func()
+
+	mu  sync.Mutex // protects pc, err, close(ready)
+	pc  *persistConn
+	err error
+}
+
+// waiting reports whether w is still waiting for an answer (connection or error).
+func (w *wantConn) waiting() bool {
+	select {
+	case <-w.ready:
+		return false
+	default:
+		return true
+	}
+}
+
+// tryDeliver attempts to deliver pc, err to w and reports whether it succeeded.
+func (w *wantConn) tryDeliver(pc *persistConn, err error) bool {
+	w.mu.Lock()
+	defer w.mu.Unlock()
+
+	if w.pc != nil || w.err != nil {
+		return false
+	}
+
+	w.pc = pc
+	w.err = err
+	if w.pc == nil && w.err == nil {
+		panic("net/http: internal error: misuse of tryDeliver")
+	}
+	close(w.ready)
+	return true
+}
+
+// cancel marks w as no longer wanting a result (for example, due to cancellation).
+// If a connection has been delivered already, cancel returns it with t.putOrCloseIdleConn.
+func (w *wantConn) cancel(t *Transport, err error) {
+	w.mu.Lock()
+	if w.pc == nil && w.err == nil {
+		close(w.ready) // catch misbehavior in future delivery
+	}
+	pc := w.pc
+	w.pc = nil
+	w.err = err
+	w.mu.Unlock()
+
+	if pc != nil {
+		t.putOrCloseIdleConn(pc)
+	}
+}
+
+// A wantConnQueue is a queue of wantConns.
+type wantConnQueue struct {
+	// This is a queue, not a deque.
+	// It is split into two stages - head[headPos:] and tail.
+	// popFront is trivial (headPos++) on the first stage, and
+	// pushBack is trivial (append) on the second stage.
+	// If the first stage is empty, popFront can swap the
+	// first and second stages to remedy the situation.
+	//
+	// This two-stage split is analogous to the use of two lists
+	// in Okasaki's purely functional queue but without the
+	// overhead of reversing the list when swapping stages.
+	head    []*wantConn
+	headPos int
+	tail    []*wantConn
+}
+
+// len returns the number of items in the queue.
+func (q *wantConnQueue) len() int {
+	return len(q.head) - q.headPos + len(q.tail)
+}
+
+// pushBack adds w to the back of the queue.
+func (q *wantConnQueue) pushBack(w *wantConn) {
+	q.tail = append(q.tail, w)
+}
+
+// popFront removes and returns the wantConn at the front of the queue.
+func (q *wantConnQueue) popFront() *wantConn {
+	if q.headPos >= len(q.head) {
+		if len(q.tail) == 0 {
+			return nil
+		}
+		// Pick up tail as new head, clear tail.
+		q.head, q.headPos, q.tail = q.tail, 0, q.head[:0]
+	}
+	w := q.head[q.headPos]
+	q.head[q.headPos] = nil
+	q.headPos++
+	return w
+}
+
+// peekFront returns the wantConn at the front of the queue without removing it.
+func (q *wantConnQueue) peekFront() *wantConn {
+	if q.headPos < len(q.head) {
+		return q.head[q.headPos]
+	}
+	if len(q.tail) > 0 {
+		return q.tail[0]
+	}
+	return nil
+}
+
+// cleanFront pops any wantConns that are no longer waiting from the head of the
+// queue, reporting whether any were popped.
+func (q *wantConnQueue) cleanFront() (cleaned bool) {
+	for {
+		w := q.peekFront()
+		if w == nil || w.waiting() {
+			return cleaned
+		}
+		q.popFront()
+		cleaned = true
+	}
+}
+
+func (t *Transport) customDialTLS(ctx context.Context, network, addr string) (conn net.Conn, err error) {
+	if t.DialTLSContext != nil {
+		conn, err = t.DialTLSContext(ctx, network, addr)
+	} else {
+		conn, err = t.DialTLS(network, addr)
+	}
+	if conn == nil && err == nil {
+		err = errors.New("net/http: Transport.DialTLS or DialTLSContext returned (nil, nil)")
+	}
+	return
+}
+
+// getConn dials and creates a new persistConn to the target as
+// specified in the connectMethod. This includes doing a proxy CONNECT
+// and/or setting up TLS.  If this doesn't return an error, the persistConn
+// is ready to write requests to.
+func (t *Transport) getConn(treq *transportRequest, cm connectMethod) (pc *persistConn, err error) {
+	req := treq.Request
+	trace := treq.trace
+	ctx := req.Context()
+	if trace != nil && trace.GetConn != nil {
+		trace.GetConn(cm.addr())
+	}
+
+	w := &wantConn{
+		cm:         cm,
+		key:        cm.key(),
+		ctx:        ctx,
+		ready:      make(chan struct{}, 1),
+		beforeDial: testHookPrePendingDial,
+		afterDial:  testHookPostPendingDial,
+	}
+	defer func() {
+		if err != nil {
+			w.cancel(t, err)
+		}
+	}()
+
+	// Queue for idle connection.
+	if delivered := t.queueForIdleConn(w); delivered {
+		pc := w.pc
+		// Trace only for HTTP/1.
+		// HTTP/2 calls trace.GotConn itself.
+		if pc.alt == nil && trace != nil && trace.GotConn != nil {
+			trace.GotConn(pc.gotIdleConnTrace(pc.idleAt))
+		}
+		// set request canceler to some non-nil function so we
+		// can detect whether it was cleared between now and when
+		// we enter roundTrip
+		t.setReqCanceler(treq.cancelKey, func(error) {})
+		return pc, nil
+	}
+
+	cancelc := make(chan error, 1)
+	t.setReqCanceler(treq.cancelKey, func(err error) { cancelc <- err })
+
+	// Queue for permission to dial.
+	t.queueForDial(w)
+
+	// Wait for completion or cancellation.
+	select {
+	case <-w.ready:
+		// Trace success but only for HTTP/1.
+		// HTTP/2 calls trace.GotConn itself.
+		if w.pc != nil && w.pc.alt == nil && trace != nil && trace.GotConn != nil {
+			trace.GotConn(httptrace.GotConnInfo{Conn: w.pc.conn, Reused: w.pc.isReused()})
+		}
+		if w.err != nil {
+			// If the request has been canceled, that's probably
+			// what caused w.err; if so, prefer to return the
+			// cancellation error (see golang.org/issue/16049).
+			select {
+			case <-req.Cancel:
+				return nil, errRequestCanceledConn
+			case <-req.Context().Done():
+				return nil, req.Context().Err()
+			case err := <-cancelc:
+				if err == errRequestCanceled {
+					err = errRequestCanceledConn
+				}
+				return nil, err
+			default:
+				// return below
+			}
+		}
+		return w.pc, w.err
+	case <-req.Cancel:
+		return nil, errRequestCanceledConn
+	case <-req.Context().Done():
+		return nil, req.Context().Err()
+	case err := <-cancelc:
+		if err == errRequestCanceled {
+			err = errRequestCanceledConn
+		}
+		return nil, err
+	}
+}
+
+// queueForDial queues w to wait for permission to begin dialing.
+// Once w receives permission to dial, it will do so in a separate goroutine.
+func (t *Transport) queueForDial(w *wantConn) {
+	w.beforeDial()
+	if t.MaxConnsPerHost <= 0 {
+		go t.dialConnFor(w)
+		return
+	}
+
+	t.connsPerHostMu.Lock()
+	defer t.connsPerHostMu.Unlock()
+
+	if n := t.connsPerHost[w.key]; n < t.MaxConnsPerHost {
+		if t.connsPerHost == nil {
+			t.connsPerHost = make(map[connectMethodKey]int)
+		}
+		t.connsPerHost[w.key] = n + 1
+		go t.dialConnFor(w)
+		return
+	}
+
+	if t.connsPerHostWait == nil {
+		t.connsPerHostWait = make(map[connectMethodKey]wantConnQueue)
+	}
+	q := t.connsPerHostWait[w.key]
+	q.cleanFront()
+	q.pushBack(w)
+	t.connsPerHostWait[w.key] = q
+}
+
+// dialConnFor dials on behalf of w and delivers the result to w.
+// dialConnFor has received permission to dial w.cm and is counted in t.connCount[w.cm.key()].
+// If the dial is canceled or unsuccessful, dialConnFor decrements t.connCount[w.cm.key()].
+func (t *Transport) dialConnFor(w *wantConn) {
+	defer w.afterDial()
+
+	pc, err := t.dialConn(w.ctx, w.cm)
+	delivered := w.tryDeliver(pc, err)
+	if err == nil && (!delivered || pc.alt != nil) {
+		// pconn was not passed to w,
+		// or it is HTTP/2 and can be shared.
+		// Add to the idle connection pool.
+		t.putOrCloseIdleConn(pc)
+	}
+	if err != nil {
+		t.decConnsPerHost(w.key)
+	}
+}
+
+// decConnsPerHost decrements the per-host connection count for key,
+// which may in turn give a different waiting goroutine permission to dial.
+func (t *Transport) decConnsPerHost(key connectMethodKey) {
+	if t.MaxConnsPerHost <= 0 {
+		return
+	}
+
+	t.connsPerHostMu.Lock()
+	defer t.connsPerHostMu.Unlock()
+	n := t.connsPerHost[key]
+	if n == 0 {
+		// Shouldn't happen, but if it does, the counting is buggy and could
+		// easily lead to a silent deadlock, so report the problem loudly.
+		panic("net/http: internal error: connCount underflow")
+	}
+
+	// Can we hand this count to a goroutine still waiting to dial?
+	// (Some goroutines on the wait list may have timed out or
+	// gotten a connection another way. If they're all gone,
+	// we don't want to kick off any spurious dial operations.)
+	if q := t.connsPerHostWait[key]; q.len() > 0 {
+		done := false
+		for q.len() > 0 {
+			w := q.popFront()
+			if w.waiting() {
+				go t.dialConnFor(w)
+				done = true
+				break
+			}
+		}
+		if q.len() == 0 {
+			delete(t.connsPerHostWait, key)
+		} else {
+			// q is a value (like a slice), so we have to store
+			// the updated q back into the map.
+			t.connsPerHostWait[key] = q
+		}
+		if done {
+			return
+		}
+	}
+
+	// Otherwise, decrement the recorded count.
+	if n--; n == 0 {
+		delete(t.connsPerHost, key)
+	} else {
+		t.connsPerHost[key] = n
+	}
+}
+
+// Add TLS to a persistent connection, i.e. negotiate a TLS session. If pconn is already a TLS
+// tunnel, this function establishes a nested TLS session inside the encrypted channel.
+// The remote endpoint's name may be overridden by TLSClientConfig.ServerName.
+func (pconn *persistConn) addTLS(ctx context.Context, name string, trace *httptrace.ClientTrace) error {
+	// Initiate TLS and check remote host name against certificate.
+	cfg := cloneTLSConfig(pconn.t.TLSClientConfig)
+	if cfg.ServerName == "" {
+		cfg.ServerName = name
+	}
+	if pconn.cacheKey.onlyH1 {
+		cfg.NextProtos = nil
+	}
+	plainConn := pconn.conn
+	tlsConn := tls.Client(plainConn, cfg)
+	errc := make(chan error, 2)
+	var timer *time.Timer // for canceling TLS handshake
+	if d := pconn.t.TLSHandshakeTimeout; d != 0 {
+		timer = time.AfterFunc(d, func() {
+			errc <- tlsHandshakeTimeoutError{}
+		})
+	}
+	go func() {
+		if trace != nil && trace.TLSHandshakeStart != nil {
+			trace.TLSHandshakeStart()
+		}
+		err := tlsConn.HandshakeContext(ctx)
+		if timer != nil {
+			timer.Stop()
+		}
+		errc <- err
+	}()
+	if err := <-errc; err != nil {
+		plainConn.Close()
+		if trace != nil && trace.TLSHandshakeDone != nil {
+			trace.TLSHandshakeDone(tls.ConnectionState{}, err)
+		}
+		return err
+	}
+	cs := tlsConn.ConnectionState()
+	if trace != nil && trace.TLSHandshakeDone != nil {
+		trace.TLSHandshakeDone(cs, nil)
+	}
+	pconn.tlsState = &cs
+	pconn.conn = tlsConn
+	return nil
+}
+
+type erringRoundTripper interface {
+	RoundTripErr() error
+}
+
+func (t *Transport) dialConn(ctx context.Context, cm connectMethod) (pconn *persistConn, err error) {
+	pconn = &persistConn{
+		t:             t,
+		cacheKey:      cm.key(),
+		reqch:         make(chan requestAndChan, 1),
+		writech:       make(chan writeRequest, 1),
+		closech:       make(chan struct{}),
+		writeErrCh:    make(chan error, 1),
+		writeLoopDone: make(chan struct{}),
+	}
+	trace := httptrace.ContextClientTrace(ctx)
+	wrapErr := func(err error) error {
+		if cm.proxyURL != nil {
+			// Return a typed error, per Issue 16997
+			return &net.OpError{Op: "proxyconnect", Net: "tcp", Err: err}
+		}
+		return err
+	}
+	if cm.scheme() == "https" && t.hasCustomTLSDialer() {
+		var err error
+		pconn.conn, err = t.customDialTLS(ctx, "tcp", cm.addr())
+		if err != nil {
+			return nil, wrapErr(err)
+		}
+		if tc, ok := pconn.conn.(*tls.Conn); ok {
+			// Handshake here, in case DialTLS didn't. TLSNextProto below
+			// depends on it for knowing the connection state.
+			if trace != nil && trace.TLSHandshakeStart != nil {
+				trace.TLSHandshakeStart()
+			}
+			if err := tc.HandshakeContext(ctx); err != nil {
+				go pconn.conn.Close()
+				if trace != nil && trace.TLSHandshakeDone != nil {
+					trace.TLSHandshakeDone(tls.ConnectionState{}, err)
+				}
+				return nil, err
+			}
+			cs := tc.ConnectionState()
+			if trace != nil && trace.TLSHandshakeDone != nil {
+				trace.TLSHandshakeDone(cs, nil)
+			}
+			pconn.tlsState = &cs
+		}
+	} else {
+		conn, err := t.dial(ctx, "tcp", cm.addr())
+		if err != nil {
+			return nil, wrapErr(err)
+		}
+		pconn.conn = conn
+		if cm.scheme() == "https" {
+			var firstTLSHost string
+			if firstTLSHost, _, err = net.SplitHostPort(cm.addr()); err != nil {
+				return nil, wrapErr(err)
+			}
+			if err = pconn.addTLS(ctx, firstTLSHost, trace); err != nil {
+				return nil, wrapErr(err)
+			}
+		}
+	}
+
+	// Proxy setup.
+	switch {
+	case cm.proxyURL == nil:
+		// Do nothing. Not using a proxy.
+	case cm.proxyURL.Scheme == "socks5":
+		conn := pconn.conn
+		d := socksNewDialer("tcp", conn.RemoteAddr().String())
+		if u := cm.proxyURL.User; u != nil {
+			auth := &socksUsernamePassword{
+				Username: u.Username(),
+			}
+			auth.Password, _ = u.Password()
+			d.AuthMethods = []socksAuthMethod{
+				socksAuthMethodNotRequired,
+				socksAuthMethodUsernamePassword,
+			}
+			d.Authenticate = auth.Authenticate
+		}
+		if _, err := d.DialWithConn(ctx, conn, "tcp", cm.targetAddr); err != nil {
+			conn.Close()
+			return nil, err
+		}
+	case cm.targetScheme == "http":
+		pconn.isProxy = true
+		if pa := cm.proxyAuth(); pa != "" {
+			pconn.mutateHeaderFunc = func(h Header) {
+				h.Set("Proxy-Authorization", pa)
+			}
+		}
+	case cm.targetScheme == "https":
+		conn := pconn.conn
+		var hdr Header
+		if t.GetProxyConnectHeader != nil {
+			var err error
+			hdr, err = t.GetProxyConnectHeader(ctx, cm.proxyURL, cm.targetAddr)
+			if err != nil {
+				conn.Close()
+				return nil, err
+			}
+		} else {
+			hdr = t.ProxyConnectHeader
+		}
+		if hdr == nil {
+			hdr = make(Header)
+		}
+		if pa := cm.proxyAuth(); pa != "" {
+			hdr = hdr.Clone()
+			hdr.Set("Proxy-Authorization", pa)
+		}
+		connectReq := &Request{
+			Method: "CONNECT",
+			URL:    &url.URL{Opaque: cm.targetAddr},
+			Host:   cm.targetAddr,
+			Header: hdr,
+		}
+
+		// If there's no done channel (no deadline or cancellation
+		// from the caller possible), at least set some (long)
+		// timeout here. This will make sure we don't block forever
+		// and leak a goroutine if the connection stops replying
+		// after the TCP connect.
+		connectCtx := ctx
+		if ctx.Done() == nil {
+			newCtx, cancel := context.WithTimeout(ctx, 1*time.Minute)
+			defer cancel()
+			connectCtx = newCtx
+		}
+
+		didReadResponse := make(chan struct{}) // closed after CONNECT write+read is done or fails
+		var (
+			resp *Response
+			err  error // write or read error
+		)
+		// Write the CONNECT request & read the response.
+		go func() {
+			defer close(didReadResponse)
+			err = connectReq.Write(conn)
+			if err != nil {
+				return
+			}
+			// Okay to use and discard buffered reader here, because
+			// TLS server will not speak until spoken to.
+			br := bufio.NewReader(conn)
+			resp, err = ReadResponse(br, connectReq)
+		}()
+		select {
+		case <-connectCtx.Done():
+			conn.Close()
+			<-didReadResponse
+			return nil, connectCtx.Err()
+		case <-didReadResponse:
+			// resp or err now set
+		}
+		if err != nil {
+			conn.Close()
+			return nil, err
+		}
+		if resp.StatusCode != 200 {
+			_, text, ok := strings.Cut(resp.Status, " ")
+			conn.Close()
+			if !ok {
+				return nil, errors.New("unknown status code")
+			}
+			return nil, errors.New(text)
+		}
+	}
+
+	if cm.proxyURL != nil && cm.targetScheme == "https" {
+		if err := pconn.addTLS(ctx, cm.tlsHost(), trace); err != nil {
+			return nil, err
+		}
+	}
+
+	if s := pconn.tlsState; s != nil && s.NegotiatedProtocolIsMutual && s.NegotiatedProtocol != "" {
+		if next, ok := t.TLSNextProto[s.NegotiatedProtocol]; ok {
+			alt := next(cm.targetAddr, pconn.conn.(*tls.Conn))
+			if e, ok := alt.(erringRoundTripper); ok {
+				// pconn.conn was closed by next (http2configureTransports.upgradeFn).
+				return nil, e.RoundTripErr()
+			}
+			return &persistConn{t: t, cacheKey: pconn.cacheKey, alt: alt}, nil
+		}
+	}
+
+	pconn.br = bufio.NewReaderSize(pconn, t.readBufferSize())
+	pconn.bw = bufio.NewWriterSize(persistConnWriter{pconn}, t.writeBufferSize())
+
+	go pconn.readLoop()
+	go pconn.writeLoop()
+	return pconn, nil
+}
+
+// persistConnWriter is the io.Writer written to by pc.bw.
+// It accumulates the number of bytes written to the underlying conn,
+// so the retry logic can determine whether any bytes made it across
+// the wire.
+// This is exactly 1 pointer field wide so it can go into an interface
+// without allocation.
+type persistConnWriter struct {
+	pc *persistConn
+}
+
+func (w persistConnWriter) Write(p []byte) (n int, err error) {
+	n, err = w.pc.conn.Write(p)
+	w.pc.nwrite += int64(n)
+	return
+}
+
+// ReadFrom exposes persistConnWriter's underlying Conn to io.Copy and if
+// the Conn implements io.ReaderFrom, it can take advantage of optimizations
+// such as sendfile.
+func (w persistConnWriter) ReadFrom(r io.Reader) (n int64, err error) {
+	n, err = io.Copy(w.pc.conn, r)
+	w.pc.nwrite += n
+	return
+}
+
+var _ io.ReaderFrom = (*persistConnWriter)(nil)
+
+// connectMethod is the map key (in its String form) for keeping persistent
+// TCP connections alive for subsequent HTTP requests.
+//
+// A connect method may be of the following types:
+//
+//	connectMethod.key().String()      Description
+//	------------------------------    -------------------------
+//	|http|foo.com                     http directly to server, no proxy
+//	|https|foo.com                    https directly to server, no proxy
+//	|https,h1|foo.com                 https directly to server w/o HTTP/2, no proxy
+//	http://proxy.com|https|foo.com    http to proxy, then CONNECT to foo.com
+//	http://proxy.com|http             http to proxy, http to anywhere after that
+//	socks5://proxy.com|http|foo.com   socks5 to proxy, then http to foo.com
+//	socks5://proxy.com|https|foo.com  socks5 to proxy, then https to foo.com
+//	https://proxy.com|https|foo.com   https to proxy, then CONNECT to foo.com
+//	https://proxy.com|http            https to proxy, http to anywhere after that
+type connectMethod struct {
+	_            incomparable
+	proxyURL     *url.URL // nil for no proxy, else full proxy URL
+	targetScheme string   // "http" or "https"
+	// If proxyURL specifies an http or https proxy, and targetScheme is http (not https),
+	// then targetAddr is not included in the connect method key, because the socket can
+	// be reused for different targetAddr values.
+	targetAddr string
+	onlyH1     bool // whether to disable HTTP/2 and force HTTP/1
+}
+
+func (cm *connectMethod) key() connectMethodKey {
+	proxyStr := ""
+	targetAddr := cm.targetAddr
+	if cm.proxyURL != nil {
+		proxyStr = cm.proxyURL.String()
+		if (cm.proxyURL.Scheme == "http" || cm.proxyURL.Scheme == "https") && cm.targetScheme == "http" {
+			targetAddr = ""
+		}
+	}
+	return connectMethodKey{
+		proxy:  proxyStr,
+		scheme: cm.targetScheme,
+		addr:   targetAddr,
+		onlyH1: cm.onlyH1,
+	}
+}
+
+// scheme returns the first hop scheme: http, https, or socks5
+func (cm *connectMethod) scheme() string {
+	if cm.proxyURL != nil {
+		return cm.proxyURL.Scheme
+	}
+	return cm.targetScheme
+}
+
+// addr returns the first hop "host:port" to which we need to TCP connect.
+func (cm *connectMethod) addr() string {
+	if cm.proxyURL != nil {
+		return canonicalAddr(cm.proxyURL)
+	}
+	return cm.targetAddr
+}
+
+// tlsHost returns the host name to match against the peer's
+// TLS certificate.
+func (cm *connectMethod) tlsHost() string {
+	h := cm.targetAddr
+	if hasPort(h) {
+		h = h[:strings.LastIndex(h, ":")]
+	}
+	return h
+}
+
+// connectMethodKey is the map key version of connectMethod, with a
+// stringified proxy URL (or the empty string) instead of a pointer to
+// a URL.
+type connectMethodKey struct {
+	proxy, scheme, addr string
+	onlyH1              bool
+}
+
+func (k connectMethodKey) String() string {
+	// Only used by tests.
+	var h1 string
+	if k.onlyH1 {
+		h1 = ",h1"
+	}
+	return fmt.Sprintf("%s|%s%s|%s", k.proxy, k.scheme, h1, k.addr)
+}
+
+// persistConn wraps a connection, usually a persistent one
+// (but may be used for non-keep-alive requests as well)
+type persistConn struct {
+	// alt optionally specifies the TLS NextProto RoundTripper.
+	// This is used for HTTP/2 today and future protocols later.
+	// If it's non-nil, the rest of the fields are unused.
+	alt RoundTripper
+
+	t         *Transport
+	cacheKey  connectMethodKey
+	conn      net.Conn
+	tlsState  *tls.ConnectionState
+	br        *bufio.Reader       // from conn
+	bw        *bufio.Writer       // to conn
+	nwrite    int64               // bytes written
+	reqch     chan requestAndChan // written by roundTrip; read by readLoop
+	writech   chan writeRequest   // written by roundTrip; read by writeLoop
+	closech   chan struct{}       // closed when conn closed
+	isProxy   bool
+	sawEOF    bool  // whether we've seen EOF from conn; owned by readLoop
+	readLimit int64 // bytes allowed to be read; owned by readLoop
+	// writeErrCh passes the request write error (usually nil)
+	// from the writeLoop goroutine to the readLoop which passes
+	// it off to the res.Body reader, which then uses it to decide
+	// whether or not a connection can be reused. Issue 7569.
+	writeErrCh chan error
+
+	writeLoopDone chan struct{} // closed when write loop ends
+
+	// Both guarded by Transport.idleMu:
+	idleAt    time.Time   // time it last become idle
+	idleTimer *time.Timer // holding an AfterFunc to close it
+
+	mu                   sync.Mutex // guards following fields
+	numExpectedResponses int
+	closed               error // set non-nil when conn is closed, before closech is closed
+	canceledErr          error // set non-nil if conn is canceled
+	broken               bool  // an error has happened on this connection; marked broken so it's not reused.
+	reused               bool  // whether conn has had successful request/response and is being reused.
+	// mutateHeaderFunc is an optional func to modify extra
+	// headers on each outbound request before it's written. (the
+	// original Request given to RoundTrip is not modified)
+	mutateHeaderFunc func(Header)
+}
+
+func (pc *persistConn) maxHeaderResponseSize() int64 {
+	if v := pc.t.MaxResponseHeaderBytes; v != 0 {
+		return v
+	}
+	return 10 << 20 // conservative default; same as http2
+}
+
+func (pc *persistConn) Read(p []byte) (n int, err error) {
+	if pc.readLimit <= 0 {
+		return 0, fmt.Errorf("read limit of %d bytes exhausted", pc.maxHeaderResponseSize())
+	}
+	if int64(len(p)) > pc.readLimit {
+		p = p[:pc.readLimit]
+	}
+	n, err = pc.conn.Read(p)
+	if err == io.EOF {
+		pc.sawEOF = true
+	}
+	pc.readLimit -= int64(n)
+	return
+}
+
+// isBroken reports whether this connection is in a known broken state.
+func (pc *persistConn) isBroken() bool {
+	pc.mu.Lock()
+	b := pc.closed != nil
+	pc.mu.Unlock()
+	return b
+}
+
+// canceled returns non-nil if the connection was closed due to
+// CancelRequest or due to context cancellation.
+func (pc *persistConn) canceled() error {
+	pc.mu.Lock()
+	defer pc.mu.Unlock()
+	return pc.canceledErr
+}
+
+// isReused reports whether this connection has been used before.
+func (pc *persistConn) isReused() bool {
+	pc.mu.Lock()
+	r := pc.reused
+	pc.mu.Unlock()
+	return r
+}
+
+func (pc *persistConn) gotIdleConnTrace(idleAt time.Time) (t httptrace.GotConnInfo) {
+	pc.mu.Lock()
+	defer pc.mu.Unlock()
+	t.Reused = pc.reused
+	t.Conn = pc.conn
+	t.WasIdle = true
+	if !idleAt.IsZero() {
+		t.IdleTime = time.Since(idleAt)
+	}
+	return
+}
+
+func (pc *persistConn) cancelRequest(err error) {
+	pc.mu.Lock()
+	defer pc.mu.Unlock()
+	pc.canceledErr = err
+	pc.closeLocked(errRequestCanceled)
+}
+
+// closeConnIfStillIdle closes the connection if it's still sitting idle.
+// This is what's called by the persistConn's idleTimer, and is run in its
+// own goroutine.
+func (pc *persistConn) closeConnIfStillIdle() {
+	t := pc.t
+	t.idleMu.Lock()
+	defer t.idleMu.Unlock()
+	if _, ok := t.idleLRU.m[pc]; !ok {
+		// Not idle.
+		return
+	}
+	t.removeIdleConnLocked(pc)
+	pc.close(errIdleConnTimeout)
+}
+
+// mapRoundTripError returns the appropriate error value for
+// persistConn.roundTrip.
+//
+// The provided err is the first error that (*persistConn).roundTrip
+// happened to receive from its select statement.
+//
+// The startBytesWritten value should be the value of pc.nwrite before the roundTrip
+// started writing the request.
+func (pc *persistConn) mapRoundTripError(req *transportRequest, startBytesWritten int64, err error) error {
+	if err == nil {
+		return nil
+	}
+
+	// Wait for the writeLoop goroutine to terminate to avoid data
+	// races on callers who mutate the request on failure.
+	//
+	// When resc in pc.roundTrip and hence rc.ch receives a responseAndError
+	// with a non-nil error it implies that the persistConn is either closed
+	// or closing. Waiting on pc.writeLoopDone is hence safe as all callers
+	// close closech which in turn ensures writeLoop returns.
+	<-pc.writeLoopDone
+
+	// If the request was canceled, that's better than network
+	// failures that were likely the result of tearing down the
+	// connection.
+	if cerr := pc.canceled(); cerr != nil {
+		return cerr
+	}
+
+	// See if an error was set explicitly.
+	req.mu.Lock()
+	reqErr := req.err
+	req.mu.Unlock()
+	if reqErr != nil {
+		return reqErr
+	}
+
+	if err == errServerClosedIdle {
+		// Don't decorate
+		return err
+	}
+
+	if _, ok := err.(transportReadFromServerError); ok {
+		if pc.nwrite == startBytesWritten {
+			return nothingWrittenError{err}
+		}
+		// Don't decorate
+		return err
+	}
+	if pc.isBroken() {
+		if pc.nwrite == startBytesWritten {
+			return nothingWrittenError{err}
+		}
+		return fmt.Errorf("net/http: HTTP/1.x transport connection broken: %v", err)
+	}
+	return err
+}
+
+// errCallerOwnsConn is an internal sentinel error used when we hand
+// off a writable response.Body to the caller. We use this to prevent
+// closing a net.Conn that is now owned by the caller.
+var errCallerOwnsConn = errors.New("read loop ending; caller owns writable underlying conn")
+
+func (pc *persistConn) readLoop() {
+	closeErr := errReadLoopExiting // default value, if not changed below
+	defer func() {
+		pc.close(closeErr)
+		pc.t.removeIdleConn(pc)
+	}()
+
+	tryPutIdleConn := func(trace *httptrace.ClientTrace) bool {
+		if err := pc.t.tryPutIdleConn(pc); err != nil {
+			closeErr = err
+			if trace != nil && trace.PutIdleConn != nil && err != errKeepAlivesDisabled {
+				trace.PutIdleConn(err)
+			}
+			return false
+		}
+		if trace != nil && trace.PutIdleConn != nil {
+			trace.PutIdleConn(nil)
+		}
+		return true
+	}
+
+	// eofc is used to block caller goroutines reading from Response.Body
+	// at EOF until this goroutines has (potentially) added the connection
+	// back to the idle pool.
+	eofc := make(chan struct{})
+	defer close(eofc) // unblock reader on errors
+
+	// Read this once, before loop starts. (to avoid races in tests)
+	testHookMu.Lock()
+	testHookReadLoopBeforeNextRead := testHookReadLoopBeforeNextRead
+	testHookMu.Unlock()
+
+	alive := true
+	for alive {
+		pc.readLimit = pc.maxHeaderResponseSize()
+		_, err := pc.br.Peek(1)
+
+		pc.mu.Lock()
+		if pc.numExpectedResponses == 0 {
+			pc.readLoopPeekFailLocked(err)
+			pc.mu.Unlock()
+			return
+		}
+		pc.mu.Unlock()
+
+		rc := <-pc.reqch
+		trace := httptrace.ContextClientTrace(rc.req.Context())
+
+		var resp *Response
+		if err == nil {
+			resp, err = pc.readResponse(rc, trace)
+		} else {
+			err = transportReadFromServerError{err}
+			closeErr = err
+		}
+
+		if err != nil {
+			if pc.readLimit <= 0 {
+				err = fmt.Errorf("net/http: server response headers exceeded %d bytes; aborted", pc.maxHeaderResponseSize())
+			}
+
+			select {
+			case rc.ch <- responseAndError{err: err}:
+			case <-rc.callerGone:
+				return
+			}
+			return
+		}
+		pc.readLimit = maxInt64 // effectively no limit for response bodies
+
+		pc.mu.Lock()
+		pc.numExpectedResponses--
+		pc.mu.Unlock()
+
+		bodyWritable := resp.bodyIsWritable()
+		hasBody := rc.req.Method != "HEAD" && resp.ContentLength != 0
+
+		if resp.Close || rc.req.Close || resp.StatusCode <= 199 || bodyWritable {
+			// Don't do keep-alive on error if either party requested a close
+			// or we get an unexpected informational (1xx) response.
+			// StatusCode 100 is already handled above.
+			alive = false
+		}
+
+		if !hasBody || bodyWritable {
+			replaced := pc.t.replaceReqCanceler(rc.cancelKey, nil)
+
+			// Put the idle conn back into the pool before we send the response
+			// so if they process it quickly and make another request, they'll
+			// get this same conn. But we use the unbuffered channel 'rc'
+			// to guarantee that persistConn.roundTrip got out of its select
+			// potentially waiting for this persistConn to close.
+			alive = alive &&
+				!pc.sawEOF &&
+				pc.wroteRequest() &&
+				replaced && tryPutIdleConn(trace)
+
+			if bodyWritable {
+				closeErr = errCallerOwnsConn
+			}
+
+			select {
+			case rc.ch <- responseAndError{res: resp}:
+			case <-rc.callerGone:
+				return
+			}
+
+			// Now that they've read from the unbuffered channel, they're safely
+			// out of the select that also waits on this goroutine to die, so
+			// we're allowed to exit now if needed (if alive is false)
+			testHookReadLoopBeforeNextRead()
+			continue
+		}
+
+		waitForBodyRead := make(chan bool, 2)
+		body := &bodyEOFSignal{
+			body: resp.Body,
+			earlyCloseFn: func() error {
+				waitForBodyRead <- false
+				<-eofc // will be closed by deferred call at the end of the function
+				return nil
+
+			},
+			fn: func(err error) error {
+				isEOF := err == io.EOF
+				waitForBodyRead <- isEOF
+				if isEOF {
+					<-eofc // see comment above eofc declaration
+				} else if err != nil {
+					if cerr := pc.canceled(); cerr != nil {
+						return cerr
+					}
+				}
+				return err
+			},
+		}
+
+		resp.Body = body
+		if rc.addedGzip && ascii.EqualFold(resp.Header.Get("Content-Encoding"), "gzip") {
+			resp.Body = &gzipReader{body: body}
+			resp.Header.Del("Content-Encoding")
+			resp.Header.Del("Content-Length")
+			resp.ContentLength = -1
+			resp.Uncompressed = true
+		}
+
+		select {
+		case rc.ch <- responseAndError{res: resp}:
+		case <-rc.callerGone:
+			return
+		}
+
+		// Before looping back to the top of this function and peeking on
+		// the bufio.Reader, wait for the caller goroutine to finish
+		// reading the response body. (or for cancellation or death)
+		select {
+		case bodyEOF := <-waitForBodyRead:
+			replaced := pc.t.replaceReqCanceler(rc.cancelKey, nil) // before pc might return to idle pool
+			alive = alive &&
+				bodyEOF &&
+				!pc.sawEOF &&
+				pc.wroteRequest() &&
+				replaced && tryPutIdleConn(trace)
+			if bodyEOF {
+				eofc <- struct{}{}
+			}
+		case <-rc.req.Cancel:
+			alive = false
+			pc.t.CancelRequest(rc.req)
+		case <-rc.req.Context().Done():
+			alive = false
+			pc.t.cancelRequest(rc.cancelKey, rc.req.Context().Err())
+		case <-pc.closech:
+			alive = false
+		}
+
+		testHookReadLoopBeforeNextRead()
+	}
+}
+
+func (pc *persistConn) readLoopPeekFailLocked(peekErr error) {
+	if pc.closed != nil {
+		return
+	}
+	if n := pc.br.Buffered(); n > 0 {
+		buf, _ := pc.br.Peek(n)
+		if is408Message(buf) {
+			pc.closeLocked(errServerClosedIdle)
+			return
+		} else {
+			log.Printf("Unsolicited response received on idle HTTP channel starting with %q; err=%v", buf, peekErr)
+		}
+	}
+	if peekErr == io.EOF {
+		// common case.
+		pc.closeLocked(errServerClosedIdle)
+	} else {
+		pc.closeLocked(fmt.Errorf("readLoopPeekFailLocked: %v", peekErr))
+	}
+}
+
+// is408Message reports whether buf has the prefix of an
+// HTTP 408 Request Timeout response.
+// See golang.org/issue/32310.
+func is408Message(buf []byte) bool {
+	if len(buf) < len("HTTP/1.x 408") {
+		return false
+	}
+	if string(buf[:7]) != "HTTP/1." {
+		return false
+	}
+	return string(buf[8:12]) == " 408"
+}
+
+// readResponse reads an HTTP response (or two, in the case of "Expect:
+// 100-continue") from the server. It returns the final non-100 one.
+// trace is optional.
+func (pc *persistConn) readResponse(rc requestAndChan, trace *httptrace.ClientTrace) (resp *Response, err error) {
+	if trace != nil && trace.GotFirstResponseByte != nil {
+		if peek, err := pc.br.Peek(1); err == nil && len(peek) == 1 {
+			trace.GotFirstResponseByte()
+		}
+	}
+	num1xx := 0               // number of informational 1xx headers received
+	const max1xxResponses = 5 // arbitrary bound on number of informational responses
+
+	continueCh := rc.continueCh
+	for {
+		resp, err = ReadResponse(pc.br, rc.req)
+		if err != nil {
+			return
+		}
+		resCode := resp.StatusCode
+		if continueCh != nil {
+			if resCode == 100 {
+				if trace != nil && trace.Got100Continue != nil {
+					trace.Got100Continue()
+				}
+				continueCh <- struct{}{}
+				continueCh = nil
+			} else if resCode >= 200 {
+				close(continueCh)
+				continueCh = nil
+			}
+		}
+		is1xx := 100 <= resCode && resCode <= 199
+		// treat 101 as a terminal status, see issue 26161
+		is1xxNonTerminal := is1xx && resCode != StatusSwitchingProtocols
+		if is1xxNonTerminal {
+			num1xx++
+			if num1xx > max1xxResponses {
+				return nil, errors.New("net/http: too many 1xx informational responses")
+			}
+			pc.readLimit = pc.maxHeaderResponseSize() // reset the limit
+			if trace != nil && trace.Got1xxResponse != nil {
+				if err := trace.Got1xxResponse(resCode, textproto.MIMEHeader(resp.Header)); err != nil {
+					return nil, err
+				}
+			}
+			continue
+		}
+		break
+	}
+	if resp.isProtocolSwitch() {
+		resp.Body = newReadWriteCloserBody(pc.br, pc.conn)
+	}
+
+	resp.TLS = pc.tlsState
+	return
+}
+
+// waitForContinue returns the function to block until
+// any response, timeout or connection close. After any of them,
+// the function returns a bool which indicates if the body should be sent.
+func (pc *persistConn) waitForContinue(continueCh <-chan struct{}) func() bool {
+	if continueCh == nil {
+		return nil
+	}
+	return func() bool {
+		timer := time.NewTimer(pc.t.ExpectContinueTimeout)
+		defer timer.Stop()
+
+		select {
+		case _, ok := <-continueCh:
+			return ok
+		case <-timer.C:
+			return true
+		case <-pc.closech:
+			return false
+		}
+	}
+}
+
+func newReadWriteCloserBody(br *bufio.Reader, rwc io.ReadWriteCloser) io.ReadWriteCloser {
+	body := &readWriteCloserBody{ReadWriteCloser: rwc}
+	if br.Buffered() != 0 {
+		body.br = br
+	}
+	return body
+}
+
+// readWriteCloserBody is the Response.Body type used when we want to
+// give users write access to the Body through the underlying
+// connection (TCP, unless using custom dialers). This is then
+// the concrete type for a Response.Body on the 101 Switching
+// Protocols response, as used by WebSockets, h2c, etc.
+type readWriteCloserBody struct {
+	_  incomparable
+	br *bufio.Reader // used until empty
+	io.ReadWriteCloser
+}
+
+func (b *readWriteCloserBody) Read(p []byte) (n int, err error) {
+	if b.br != nil {
+		if n := b.br.Buffered(); len(p) > n {
+			p = p[:n]
+		}
+		n, err = b.br.Read(p)
+		if b.br.Buffered() == 0 {
+			b.br = nil
+		}
+		return n, err
+	}
+	return b.ReadWriteCloser.Read(p)
+}
+
+// nothingWrittenError wraps a write errors which ended up writing zero bytes.
+type nothingWrittenError struct {
+	error
+}
+
+func (pc *persistConn) writeLoop() {
+	defer close(pc.writeLoopDone)
+	for {
+		select {
+		case wr := <-pc.writech:
+			startBytesWritten := pc.nwrite
+			err := wr.req.Request.write(pc.bw, pc.isProxy, wr.req.extra, pc.waitForContinue(wr.continueCh))
+			if bre, ok := err.(requestBodyReadError); ok {
+				err = bre.error
+				// Errors reading from the user's
+				// Request.Body are high priority.
+				// Set it here before sending on the
+				// channels below or calling
+				// pc.close() which tears down
+				// connections and causes other
+				// errors.
+				wr.req.setError(err)
+			}
+			if err == nil {
+				err = pc.bw.Flush()
+			}
+			if err != nil {
+				if pc.nwrite == startBytesWritten {
+					err = nothingWrittenError{err}
+				}
+			}
+			pc.writeErrCh <- err // to the body reader, which might recycle us
+			wr.ch <- err         // to the roundTrip function
+			if err != nil {
+				pc.close(err)
+				return
+			}
+		case <-pc.closech:
+			return
+		}
+	}
+}
+
+// maxWriteWaitBeforeConnReuse is how long the a Transport RoundTrip
+// will wait to see the Request's Body.Write result after getting a
+// response from the server. See comments in (*persistConn).wroteRequest.
+const maxWriteWaitBeforeConnReuse = 50 * time.Millisecond
+
+// wroteRequest is a check before recycling a connection that the previous write
+// (from writeLoop above) happened and was successful.
+func (pc *persistConn) wroteRequest() bool {
+	select {
+	case err := <-pc.writeErrCh:
+		// Common case: the write happened well before the response, so
+		// avoid creating a timer.
+		return err == nil
+	default:
+		// Rare case: the request was written in writeLoop above but
+		// before it could send to pc.writeErrCh, the reader read it
+		// all, processed it, and called us here. In this case, give the
+		// write goroutine a bit of time to finish its send.
+		//
+		// Less rare case: We also get here in the legitimate case of
+		// Issue 7569, where the writer is still writing (or stalled),
+		// but the server has already replied. In this case, we don't
+		// want to wait too long, and we want to return false so this
+		// connection isn't re-used.
+		t := time.NewTimer(maxWriteWaitBeforeConnReuse)
+		defer t.Stop()
+		select {
+		case err := <-pc.writeErrCh:
+			return err == nil
+		case <-t.C:
+			return false
+		}
+	}
+}
+
+// responseAndError is how the goroutine reading from an HTTP/1 server
+// communicates with the goroutine doing the RoundTrip.
+type responseAndError struct {
+	_   incomparable
+	res *Response // else use this response (see res method)
+	err error
+}
+
+type requestAndChan struct {
+	_         incomparable
+	req       *Request
+	cancelKey cancelKey
+	ch        chan responseAndError // unbuffered; always send in select on callerGone
+
+	// whether the Transport (as opposed to the user client code)
+	// added the Accept-Encoding gzip header. If the Transport
+	// set it, only then do we transparently decode the gzip.
+	addedGzip bool
+
+	// Optional blocking chan for Expect: 100-continue (for send).
+	// If the request has an "Expect: 100-continue" header and
+	// the server responds 100 Continue, readLoop send a value
+	// to writeLoop via this chan.
+	continueCh chan<- struct{}
+
+	callerGone <-chan struct{} // closed when roundTrip caller has returned
+}
+
+// A writeRequest is sent by the caller's goroutine to the
+// writeLoop's goroutine to write a request while the read loop
+// concurrently waits on both the write response and the server's
+// reply.
+type writeRequest struct {
+	req *transportRequest
+	ch  chan<- error
+
+	// Optional blocking chan for Expect: 100-continue (for receive).
+	// If not nil, writeLoop blocks sending request body until
+	// it receives from this chan.
+	continueCh <-chan struct{}
+}
+
+type httpError struct {
+	err     string
+	timeout bool
+}
+
+func (e *httpError) Error() string   { return e.err }
+func (e *httpError) Timeout() bool   { return e.timeout }
+func (e *httpError) Temporary() bool { return true }
+
+var errTimeout error = &httpError{err: "net/http: timeout awaiting response headers", timeout: true}
+
+// errRequestCanceled is set to be identical to the one from h2 to facilitate
+// testing.
+var errRequestCanceled = http2errRequestCanceled
+var errRequestCanceledConn = errors.New("net/http: request canceled while waiting for connection") // TODO: unify?
+
+func nop() {}
+
+// testHooks. Always non-nil.
+var (
+	testHookEnterRoundTrip   = nop
+	testHookWaitResLoop      = nop
+	testHookRoundTripRetried = nop
+	testHookPrePendingDial   = nop
+	testHookPostPendingDial  = nop
+
+	testHookMu                     sync.Locker = fakeLocker{} // guards following
+	testHookReadLoopBeforeNextRead             = nop
+)
+
+func (pc *persistConn) roundTrip(req *transportRequest) (resp *Response, err error) {
+	testHookEnterRoundTrip()
+	if !pc.t.replaceReqCanceler(req.cancelKey, pc.cancelRequest) {
+		pc.t.putOrCloseIdleConn(pc)
+		return nil, errRequestCanceled
+	}
+	pc.mu.Lock()
+	pc.numExpectedResponses++
+	headerFn := pc.mutateHeaderFunc
+	pc.mu.Unlock()
+
+	if headerFn != nil {
+		headerFn(req.extraHeaders())
+	}
+
+	// Ask for a compressed version if the caller didn't set their
+	// own value for Accept-Encoding. We only attempt to
+	// uncompress the gzip stream if we were the layer that
+	// requested it.
+	requestedGzip := false
+	if !pc.t.DisableCompression &&
+		req.Header.Get("Accept-Encoding") == "" &&
+		req.Header.Get("Range") == "" &&
+		req.Method != "HEAD" {
+		// Request gzip only, not deflate. Deflate is ambiguous and
+		// not as universally supported anyway.
+		// See: https://zlib.net/zlib_faq.html#faq39
+		//
+		// Note that we don't request this for HEAD requests,
+		// due to a bug in nginx:
+		//   https://trac.nginx.org/nginx/ticket/358
+		//   https://golang.org/issue/5522
+		//
+		// We don't request gzip if the request is for a range, since
+		// auto-decoding a portion of a gzipped document will just fail
+		// anyway. See https://golang.org/issue/8923
+		requestedGzip = true
+		req.extraHeaders().Set("Accept-Encoding", "gzip")
+	}
+
+	var continueCh chan struct{}
+	if req.ProtoAtLeast(1, 1) && req.Body != nil && req.expectsContinue() {
+		continueCh = make(chan struct{}, 1)
+	}
+
+	if pc.t.DisableKeepAlives &&
+		!req.wantsClose() &&
+		!isProtocolSwitchHeader(req.Header) {
+		req.extraHeaders().Set("Connection", "close")
+	}
+
+	gone := make(chan struct{})
+	defer close(gone)
+
+	defer func() {
+		if err != nil {
+			pc.t.setReqCanceler(req.cancelKey, nil)
+		}
+	}()
+
+	const debugRoundTrip = false
+
+	// Write the request concurrently with waiting for a response,
+	// in case the server decides to reply before reading our full
+	// request body.
+	startBytesWritten := pc.nwrite
+	writeErrCh := make(chan error, 1)
+	pc.writech <- writeRequest{req, writeErrCh, continueCh}
+
+	resc := make(chan responseAndError)
+	pc.reqch <- requestAndChan{
+		req:        req.Request,
+		cancelKey:  req.cancelKey,
+		ch:         resc,
+		addedGzip:  requestedGzip,
+		continueCh: continueCh,
+		callerGone: gone,
+	}
+
+	var respHeaderTimer <-chan time.Time
+	cancelChan := req.Request.Cancel
+	ctxDoneChan := req.Context().Done()
+	pcClosed := pc.closech
+	canceled := false
+	for {
+		testHookWaitResLoop()
+		select {
+		case err := <-writeErrCh:
+			if debugRoundTrip {
+				req.logf("writeErrCh resv: %T/%#v", err, err)
+			}
+			if err != nil {
+				pc.close(fmt.Errorf("write error: %v", err))
+				return nil, pc.mapRoundTripError(req, startBytesWritten, err)
+			}
+			if d := pc.t.ResponseHeaderTimeout; d > 0 {
+				if debugRoundTrip {
+					req.logf("starting timer for %v", d)
+				}
+				timer := time.NewTimer(d)
+				defer timer.Stop() // prevent leaks
+				respHeaderTimer = timer.C
+			}
+		case <-pcClosed:
+			pcClosed = nil
+			if canceled || pc.t.replaceReqCanceler(req.cancelKey, nil) {
+				if debugRoundTrip {
+					req.logf("closech recv: %T %#v", pc.closed, pc.closed)
+				}
+				return nil, pc.mapRoundTripError(req, startBytesWritten, pc.closed)
+			}
+		case <-respHeaderTimer:
+			if debugRoundTrip {
+				req.logf("timeout waiting for response headers.")
+			}
+			pc.close(errTimeout)
+			return nil, errTimeout
+		case re := <-resc:
+			if (re.res == nil) == (re.err == nil) {
+				panic(fmt.Sprintf("internal error: exactly one of res or err should be set; nil=%v", re.res == nil))
+			}
+			if debugRoundTrip {
+				req.logf("resc recv: %p, %T/%#v", re.res, re.err, re.err)
+			}
+			if re.err != nil {
+				return nil, pc.mapRoundTripError(req, startBytesWritten, re.err)
+			}
+			return re.res, nil
+		case <-cancelChan:
+			canceled = pc.t.cancelRequest(req.cancelKey, errRequestCanceled)
+			cancelChan = nil
+		case <-ctxDoneChan:
+			canceled = pc.t.cancelRequest(req.cancelKey, req.Context().Err())
+			cancelChan = nil
+			ctxDoneChan = nil
+		}
+	}
+}
+
+// tLogKey is a context WithValue key for test debugging contexts containing
+// a t.Logf func. See export_test.go's Request.WithT method.
+type tLogKey struct{}
+
+func (tr *transportRequest) logf(format string, args ...any) {
+	if logf, ok := tr.Request.Context().Value(tLogKey{}).(func(string, ...any)); ok {
+		logf(time.Now().Format(time.RFC3339Nano)+": "+format, args...)
+	}
+}
+
+// markReused marks this connection as having been successfully used for a
+// request and response.
+func (pc *persistConn) markReused() {
+	pc.mu.Lock()
+	pc.reused = true
+	pc.mu.Unlock()
+}
+
+// close closes the underlying TCP connection and closes
+// the pc.closech channel.
+//
+// The provided err is only for testing and debugging; in normal
+// circumstances it should never be seen by users.
+func (pc *persistConn) close(err error) {
+	pc.mu.Lock()
+	defer pc.mu.Unlock()
+	pc.closeLocked(err)
+}
+
+func (pc *persistConn) closeLocked(err error) {
+	if err == nil {
+		panic("nil error")
+	}
+	pc.broken = true
+	if pc.closed == nil {
+		pc.closed = err
+		pc.t.decConnsPerHost(pc.cacheKey)
+		// Close HTTP/1 (pc.alt == nil) connection.
+		// HTTP/2 closes its connection itself.
+		if pc.alt == nil {
+			if err != errCallerOwnsConn {
+				pc.conn.Close()
+			}
+			close(pc.closech)
+		}
+	}
+	pc.mutateHeaderFunc = nil
+}
+
+var portMap = map[string]string{
+	"http":   "80",
+	"https":  "443",
+	"socks5": "1080",
+}
+
+// canonicalAddr returns url.Host but always with a ":port" suffix
+func canonicalAddr(url *url.URL) string {
+	addr := url.Hostname()
+	if v, err := idnaASCII(addr); err == nil {
+		addr = v
+	}
+	port := url.Port()
+	if port == "" {
+		port = portMap[url.Scheme]
+	}
+	return net.JoinHostPort(addr, port)
+}
+
+// bodyEOFSignal is used by the HTTP/1 transport when reading response
+// bodies to make sure we see the end of a response body before
+// proceeding and reading on the connection again.
+//
+// It wraps a ReadCloser but runs fn (if non-nil) at most
+// once, right before its final (error-producing) Read or Close call
+// returns. fn should return the new error to return from Read or Close.
+//
+// If earlyCloseFn is non-nil and Close is called before io.EOF is
+// seen, earlyCloseFn is called instead of fn, and its return value is
+// the return value from Close.
+type bodyEOFSignal struct {
+	body         io.ReadCloser
+	mu           sync.Mutex        // guards following 4 fields
+	closed       bool              // whether Close has been called
+	rerr         error             // sticky Read error
+	fn           func(error) error // err will be nil on Read io.EOF
+	earlyCloseFn func() error      // optional alt Close func used if io.EOF not seen
+}
+
+var errReadOnClosedResBody = errors.New("http: read on closed response body")
+
+func (es *bodyEOFSignal) Read(p []byte) (n int, err error) {
+	es.mu.Lock()
+	closed, rerr := es.closed, es.rerr
+	es.mu.Unlock()
+	if closed {
+		return 0, errReadOnClosedResBody
+	}
+	if rerr != nil {
+		return 0, rerr
+	}
+
+	n, err = es.body.Read(p)
+	if err != nil {
+		es.mu.Lock()
+		defer es.mu.Unlock()
+		if es.rerr == nil {
+			es.rerr = err
+		}
+		err = es.condfn(err)
+	}
+	return
+}
+
+func (es *bodyEOFSignal) Close() error {
+	es.mu.Lock()
+	defer es.mu.Unlock()
+	if es.closed {
+		return nil
+	}
+	es.closed = true
+	if es.earlyCloseFn != nil && es.rerr != io.EOF {
+		return es.earlyCloseFn()
+	}
+	err := es.body.Close()
+	return es.condfn(err)
+}
+
+// caller must hold es.mu.
+func (es *bodyEOFSignal) condfn(err error) error {
+	if es.fn == nil {
+		return err
+	}
+	err = es.fn(err)
+	es.fn = nil
+	return err
+}
+
+// gzipReader wraps a response body so it can lazily
+// call gzip.NewReader on the first call to Read
+type gzipReader struct {
+	_    incomparable
+	body *bodyEOFSignal // underlying HTTP/1 response body framing
+	zr   *gzip.Reader   // lazily-initialized gzip reader
+	zerr error          // any error from gzip.NewReader; sticky
+}
+
+func (gz *gzipReader) Read(p []byte) (n int, err error) {
+	if gz.zr == nil {
+		if gz.zerr == nil {
+			gz.zr, gz.zerr = gzip.NewReader(gz.body)
+		}
+		if gz.zerr != nil {
+			return 0, gz.zerr
+		}
+	}
+
+	gz.body.mu.Lock()
+	if gz.body.closed {
+		err = errReadOnClosedResBody
+	}
+	gz.body.mu.Unlock()
+
+	if err != nil {
+		return 0, err
+	}
+	return gz.zr.Read(p)
+}
+
+func (gz *gzipReader) Close() error {
+	return gz.body.Close()
+}
+
+type tlsHandshakeTimeoutError struct{}
+
+func (tlsHandshakeTimeoutError) Timeout() bool   { return true }
+func (tlsHandshakeTimeoutError) Temporary() bool { return true }
+func (tlsHandshakeTimeoutError) Error() string   { return "net/http: TLS handshake timeout" }
+
+// fakeLocker is a sync.Locker which does nothing. It's used to guard
+// test-only fields when not under test, to avoid runtime atomic
+// overhead.
+type fakeLocker struct{}
+
+func (fakeLocker) Lock()   {}
+func (fakeLocker) Unlock() {}
+
+// cloneTLSConfig returns a shallow clone of cfg, or a new zero tls.Config if
+// cfg is nil. This is safe to call even if cfg is in active use by a TLS
+// client or server.
+func cloneTLSConfig(cfg *tls.Config) *tls.Config {
+	if cfg == nil {
+		return &tls.Config{}
+	}
+	return cfg.Clone()
+}
+
+type connLRU struct {
+	ll *list.List // list.Element.Value type is of *persistConn
+	m  map[*persistConn]*list.Element
+}
+
+// add adds pc to the head of the linked list.
+func (cl *connLRU) add(pc *persistConn) {
+	if cl.ll == nil {
+		cl.ll = list.New()
+		cl.m = make(map[*persistConn]*list.Element)
+	}
+	ele := cl.ll.PushFront(pc)
+	if _, ok := cl.m[pc]; ok {
+		panic("persistConn was already in LRU")
+	}
+	cl.m[pc] = ele
+}
+
+func (cl *connLRU) removeOldest() *persistConn {
+	ele := cl.ll.Back()
+	pc := ele.Value.(*persistConn)
+	cl.ll.Remove(ele)
+	delete(cl.m, pc)
+	return pc
+}
+
+// remove removes pc from cl.
+func (cl *connLRU) remove(pc *persistConn) {
+	if ele, ok := cl.m[pc]; ok {
+		cl.ll.Remove(ele)
+		delete(cl.m, pc)
+	}
+}
+
+// len returns the number of items in the cache.
+func (cl *connLRU) len() int {
+	return len(cl.m)
+}
diff --git a/contrib/go/_std_1.18/src/net/http/transport_default_other.go b/contrib/go/_std_1.19/src/net/http/transport_default_other.go
index 8a2f1cc42b..8a2f1cc42b 100644
--- a/contrib/go/_std_1.18/src/net/http/transport_default_other.go
+++ b/contrib/go/_std_1.19/src/net/http/transport_default_other.go
diff --git a/contrib/go/_std_1.18/src/net/interface.go b/contrib/go/_std_1.19/src/net/interface.go
index 0e5d3202c9..0e5d3202c9 100644
--- a/contrib/go/_std_1.18/src/net/interface.go
+++ b/contrib/go/_std_1.19/src/net/interface.go
diff --git a/contrib/go/_std_1.18/src/net/interface_bsd.go b/contrib/go/_std_1.19/src/net/interface_bsd.go
index db7bc756d8..db7bc756d8 100644
--- a/contrib/go/_std_1.18/src/net/interface_bsd.go
+++ b/contrib/go/_std_1.19/src/net/interface_bsd.go
diff --git a/contrib/go/_std_1.18/src/net/interface_darwin.go b/contrib/go/_std_1.19/src/net/interface_darwin.go
index bb4fd73a98..bb4fd73a98 100644
--- a/contrib/go/_std_1.18/src/net/interface_darwin.go
+++ b/contrib/go/_std_1.19/src/net/interface_darwin.go
diff --git a/contrib/go/_std_1.18/src/net/interface_linux.go b/contrib/go/_std_1.19/src/net/interface_linux.go
index 441ab2f880..441ab2f880 100644
--- a/contrib/go/_std_1.18/src/net/interface_linux.go
+++ b/contrib/go/_std_1.19/src/net/interface_linux.go
diff --git a/contrib/go/_std_1.18/src/net/ip.go b/contrib/go/_std_1.19/src/net/ip.go
index 54c52881cf..54c52881cf 100644
--- a/contrib/go/_std_1.18/src/net/ip.go
+++ b/contrib/go/_std_1.19/src/net/ip.go
diff --git a/contrib/go/_std_1.18/src/net/iprawsock.go b/contrib/go/_std_1.19/src/net/iprawsock.go
index f18331a1fd..f18331a1fd 100644
--- a/contrib/go/_std_1.18/src/net/iprawsock.go
+++ b/contrib/go/_std_1.19/src/net/iprawsock.go
diff --git a/contrib/go/_std_1.19/src/net/iprawsock_posix.go b/contrib/go/_std_1.19/src/net/iprawsock_posix.go
new file mode 100644
index 0000000000..64112b08dd
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/iprawsock_posix.go
@@ -0,0 +1,147 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm) || windows
+
+package net
+
+import (
+	"context"
+	"syscall"
+)
+
+func sockaddrToIP(sa syscall.Sockaddr) Addr {
+	switch sa := sa.(type) {
+	case *syscall.SockaddrInet4:
+		return &IPAddr{IP: sa.Addr[0:]}
+	case *syscall.SockaddrInet6:
+		return &IPAddr{IP: sa.Addr[0:], Zone: zoneCache.name(int(sa.ZoneId))}
+	}
+	return nil
+}
+
+func (a *IPAddr) family() int {
+	if a == nil || len(a.IP) <= IPv4len {
+		return syscall.AF_INET
+	}
+	if a.IP.To4() != nil {
+		return syscall.AF_INET
+	}
+	return syscall.AF_INET6
+}
+
+func (a *IPAddr) sockaddr(family int) (syscall.Sockaddr, error) {
+	if a == nil {
+		return nil, nil
+	}
+	return ipToSockaddr(family, a.IP, 0, a.Zone)
+}
+
+func (a *IPAddr) toLocal(net string) sockaddr {
+	return &IPAddr{loopbackIP(net), a.Zone}
+}
+
+func (c *IPConn) readFrom(b []byte) (int, *IPAddr, error) {
+	// TODO(cw,rsc): consider using readv if we know the family
+	// type to avoid the header trim/copy
+	var addr *IPAddr
+	n, sa, err := c.fd.readFrom(b)
+	switch sa := sa.(type) {
+	case *syscall.SockaddrInet4:
+		addr = &IPAddr{IP: sa.Addr[0:]}
+		n = stripIPv4Header(n, b)
+	case *syscall.SockaddrInet6:
+		addr = &IPAddr{IP: sa.Addr[0:], Zone: zoneCache.name(int(sa.ZoneId))}
+	}
+	return n, addr, err
+}
+
+func stripIPv4Header(n int, b []byte) int {
+	if len(b) < 20 {
+		return n
+	}
+	l := int(b[0]&0x0f) << 2
+	if 20 > l || l > len(b) {
+		return n
+	}
+	if b[0]>>4 != 4 {
+		return n
+	}
+	copy(b, b[l:])
+	return n - l
+}
+
+func (c *IPConn) readMsg(b, oob []byte) (n, oobn, flags int, addr *IPAddr, err error) {
+	var sa syscall.Sockaddr
+	n, oobn, flags, sa, err = c.fd.readMsg(b, oob, 0)
+	switch sa := sa.(type) {
+	case *syscall.SockaddrInet4:
+		addr = &IPAddr{IP: sa.Addr[0:]}
+	case *syscall.SockaddrInet6:
+		addr = &IPAddr{IP: sa.Addr[0:], Zone: zoneCache.name(int(sa.ZoneId))}
+	}
+	return
+}
+
+func (c *IPConn) writeTo(b []byte, addr *IPAddr) (int, error) {
+	if c.fd.isConnected {
+		return 0, ErrWriteToConnected
+	}
+	if addr == nil {
+		return 0, errMissingAddress
+	}
+	sa, err := addr.sockaddr(c.fd.family)
+	if err != nil {
+		return 0, err
+	}
+	return c.fd.writeTo(b, sa)
+}
+
+func (c *IPConn) writeMsg(b, oob []byte, addr *IPAddr) (n, oobn int, err error) {
+	if c.fd.isConnected {
+		return 0, 0, ErrWriteToConnected
+	}
+	if addr == nil {
+		return 0, 0, errMissingAddress
+	}
+	sa, err := addr.sockaddr(c.fd.family)
+	if err != nil {
+		return 0, 0, err
+	}
+	return c.fd.writeMsg(b, oob, sa)
+}
+
+func (sd *sysDialer) dialIP(ctx context.Context, laddr, raddr *IPAddr) (*IPConn, error) {
+	network, proto, err := parseNetwork(ctx, sd.network, true)
+	if err != nil {
+		return nil, err
+	}
+	switch network {
+	case "ip", "ip4", "ip6":
+	default:
+		return nil, UnknownNetworkError(sd.network)
+	}
+	fd, err := internetSocket(ctx, network, laddr, raddr, syscall.SOCK_RAW, proto, "dial", sd.Dialer.Control)
+	if err != nil {
+		return nil, err
+	}
+	return newIPConn(fd), nil
+}
+
+func (sl *sysListener) listenIP(ctx context.Context, laddr *IPAddr) (*IPConn, error) {
+	network, proto, err := parseNetwork(ctx, sl.network, true)
+	if err != nil {
+		return nil, err
+	}
+	switch network {
+	case "ip", "ip4", "ip6":
+	default:
+		return nil, UnknownNetworkError(sl.network)
+	}
+	fd, err := internetSocket(ctx, network, laddr, nil, syscall.SOCK_RAW, proto, "listen", sl.ListenConfig.Control)
+	if err != nil {
+		return nil, err
+	}
+	return newIPConn(fd), nil
+}
diff --git a/contrib/go/_std_1.18/src/net/ipsock.go b/contrib/go/_std_1.19/src/net/ipsock.go
index 0f5da2577c..0f5da2577c 100644
--- a/contrib/go/_std_1.18/src/net/ipsock.go
+++ b/contrib/go/_std_1.19/src/net/ipsock.go
diff --git a/contrib/go/_std_1.19/src/net/ipsock_posix.go b/contrib/go/_std_1.19/src/net/ipsock_posix.go
new file mode 100644
index 0000000000..7bb66f2d6c
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/ipsock_posix.go
@@ -0,0 +1,232 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm) || windows
+
+package net
+
+import (
+	"context"
+	"internal/poll"
+	"net/netip"
+	"runtime"
+	"syscall"
+)
+
+// probe probes IPv4, IPv6 and IPv4-mapped IPv6 communication
+// capabilities which are controlled by the IPV6_V6ONLY socket option
+// and kernel configuration.
+//
+// Should we try to use the IPv4 socket interface if we're only
+// dealing with IPv4 sockets? As long as the host system understands
+// IPv4-mapped IPv6, it's okay to pass IPv4-mapped IPv6 addresses to
+// the IPv6 interface. That simplifies our code and is most
+// general. Unfortunately, we need to run on kernels built without
+// IPv6 support too. So probe the kernel to figure it out.
+func (p *ipStackCapabilities) probe() {
+	s, err := sysSocket(syscall.AF_INET, syscall.SOCK_STREAM, syscall.IPPROTO_TCP)
+	switch err {
+	case syscall.EAFNOSUPPORT, syscall.EPROTONOSUPPORT:
+	case nil:
+		poll.CloseFunc(s)
+		p.ipv4Enabled = true
+	}
+	var probes = []struct {
+		laddr TCPAddr
+		value int
+	}{
+		// IPv6 communication capability
+		{laddr: TCPAddr{IP: ParseIP("::1")}, value: 1},
+		// IPv4-mapped IPv6 address communication capability
+		{laddr: TCPAddr{IP: IPv4(127, 0, 0, 1)}, value: 0},
+	}
+	switch runtime.GOOS {
+	case "dragonfly", "openbsd":
+		// The latest DragonFly BSD and OpenBSD kernels don't
+		// support IPV6_V6ONLY=0. They always return an error
+		// and we don't need to probe the capability.
+		probes = probes[:1]
+	}
+	for i := range probes {
+		s, err := sysSocket(syscall.AF_INET6, syscall.SOCK_STREAM, syscall.IPPROTO_TCP)
+		if err != nil {
+			continue
+		}
+		defer poll.CloseFunc(s)
+		syscall.SetsockoptInt(s, syscall.IPPROTO_IPV6, syscall.IPV6_V6ONLY, probes[i].value)
+		sa, err := probes[i].laddr.sockaddr(syscall.AF_INET6)
+		if err != nil {
+			continue
+		}
+		if err := syscall.Bind(s, sa); err != nil {
+			continue
+		}
+		if i == 0 {
+			p.ipv6Enabled = true
+		} else {
+			p.ipv4MappedIPv6Enabled = true
+		}
+	}
+}
+
+// favoriteAddrFamily returns the appropriate address family for the
+// given network, laddr, raddr and mode.
+//
+// If mode indicates "listen" and laddr is a wildcard, we assume that
+// the user wants to make a passive-open connection with a wildcard
+// address family, both AF_INET and AF_INET6, and a wildcard address
+// like the following:
+//
+//   - A listen for a wildcard communication domain, "tcp" or
+//     "udp", with a wildcard address: If the platform supports
+//     both IPv6 and IPv4-mapped IPv6 communication capabilities,
+//     or does not support IPv4, we use a dual stack, AF_INET6 and
+//     IPV6_V6ONLY=0, wildcard address listen. The dual stack
+//     wildcard address listen may fall back to an IPv6-only,
+//     AF_INET6 and IPV6_V6ONLY=1, wildcard address listen.
+//     Otherwise we prefer an IPv4-only, AF_INET, wildcard address
+//     listen.
+//
+//   - A listen for a wildcard communication domain, "tcp" or
+//     "udp", with an IPv4 wildcard address: same as above.
+//
+//   - A listen for a wildcard communication domain, "tcp" or
+//     "udp", with an IPv6 wildcard address: same as above.
+//
+//   - A listen for an IPv4 communication domain, "tcp4" or "udp4",
+//     with an IPv4 wildcard address: We use an IPv4-only, AF_INET,
+//     wildcard address listen.
+//
+//   - A listen for an IPv6 communication domain, "tcp6" or "udp6",
+//     with an IPv6 wildcard address: We use an IPv6-only, AF_INET6
+//     and IPV6_V6ONLY=1, wildcard address listen.
+//
+// Otherwise guess: If the addresses are IPv4 then returns AF_INET,
+// or else returns AF_INET6. It also returns a boolean value what
+// designates IPV6_V6ONLY option.
+//
+// Note that the latest DragonFly BSD and OpenBSD kernels allow
+// neither "net.inet6.ip6.v6only=1" change nor IPPROTO_IPV6 level
+// IPV6_V6ONLY socket option setting.
+func favoriteAddrFamily(network string, laddr, raddr sockaddr, mode string) (family int, ipv6only bool) {
+	switch network[len(network)-1] {
+	case '4':
+		return syscall.AF_INET, false
+	case '6':
+		return syscall.AF_INET6, true
+	}
+
+	if mode == "listen" && (laddr == nil || laddr.isWildcard()) {
+		if supportsIPv4map() || !supportsIPv4() {
+			return syscall.AF_INET6, false
+		}
+		if laddr == nil {
+			return syscall.AF_INET, false
+		}
+		return laddr.family(), false
+	}
+
+	if (laddr == nil || laddr.family() == syscall.AF_INET) &&
+		(raddr == nil || raddr.family() == syscall.AF_INET) {
+		return syscall.AF_INET, false
+	}
+	return syscall.AF_INET6, false
+}
+
+func internetSocket(ctx context.Context, net string, laddr, raddr sockaddr, sotype, proto int, mode string, ctrlFn func(string, string, syscall.RawConn) error) (fd *netFD, err error) {
+	if (runtime.GOOS == "aix" || runtime.GOOS == "windows" || runtime.GOOS == "openbsd") && mode == "dial" && raddr.isWildcard() {
+		raddr = raddr.toLocal(net)
+	}
+	family, ipv6only := favoriteAddrFamily(net, laddr, raddr, mode)
+	return socket(ctx, net, family, sotype, proto, ipv6only, laddr, raddr, ctrlFn)
+}
+
+func ipToSockaddrInet4(ip IP, port int) (syscall.SockaddrInet4, error) {
+	if len(ip) == 0 {
+		ip = IPv4zero
+	}
+	ip4 := ip.To4()
+	if ip4 == nil {
+		return syscall.SockaddrInet4{}, &AddrError{Err: "non-IPv4 address", Addr: ip.String()}
+	}
+	sa := syscall.SockaddrInet4{Port: port}
+	copy(sa.Addr[:], ip4)
+	return sa, nil
+}
+
+func ipToSockaddrInet6(ip IP, port int, zone string) (syscall.SockaddrInet6, error) {
+	// In general, an IP wildcard address, which is either
+	// "0.0.0.0" or "::", means the entire IP addressing
+	// space. For some historical reason, it is used to
+	// specify "any available address" on some operations
+	// of IP node.
+	//
+	// When the IP node supports IPv4-mapped IPv6 address,
+	// we allow a listener to listen to the wildcard
+	// address of both IP addressing spaces by specifying
+	// IPv6 wildcard address.
+	if len(ip) == 0 || ip.Equal(IPv4zero) {
+		ip = IPv6zero
+	}
+	// We accept any IPv6 address including IPv4-mapped
+	// IPv6 address.
+	ip6 := ip.To16()
+	if ip6 == nil {
+		return syscall.SockaddrInet6{}, &AddrError{Err: "non-IPv6 address", Addr: ip.String()}
+	}
+	sa := syscall.SockaddrInet6{Port: port, ZoneId: uint32(zoneCache.index(zone))}
+	copy(sa.Addr[:], ip6)
+	return sa, nil
+}
+
+func ipToSockaddr(family int, ip IP, port int, zone string) (syscall.Sockaddr, error) {
+	switch family {
+	case syscall.AF_INET:
+		sa, err := ipToSockaddrInet4(ip, port)
+		if err != nil {
+			return nil, err
+		}
+		return &sa, nil
+	case syscall.AF_INET6:
+		sa, err := ipToSockaddrInet6(ip, port, zone)
+		if err != nil {
+			return nil, err
+		}
+		return &sa, nil
+	}
+	return nil, &AddrError{Err: "invalid address family", Addr: ip.String()}
+}
+
+func addrPortToSockaddrInet4(ap netip.AddrPort) (syscall.SockaddrInet4, error) {
+	// ipToSockaddrInet4 has special handling here for zero length slices.
+	// We do not, because netip has no concept of a generic zero IP address.
+	addr := ap.Addr()
+	if !addr.Is4() {
+		return syscall.SockaddrInet4{}, &AddrError{Err: "non-IPv4 address", Addr: addr.String()}
+	}
+	sa := syscall.SockaddrInet4{
+		Addr: addr.As4(),
+		Port: int(ap.Port()),
+	}
+	return sa, nil
+}
+
+func addrPortToSockaddrInet6(ap netip.AddrPort) (syscall.SockaddrInet6, error) {
+	// ipToSockaddrInet6 has special handling here for zero length slices.
+	// We do not, because netip has no concept of a generic zero IP address.
+	//
+	// addr is allowed to be an IPv4 address, because As16 will convert it
+	// to an IPv4-mapped IPv6 address.
+	// The error message is kept consistent with ipToSockaddrInet6.
+	addr := ap.Addr()
+	if !addr.IsValid() {
+		return syscall.SockaddrInet6{}, &AddrError{Err: "non-IPv6 address", Addr: addr.String()}
+	}
+	sa := syscall.SockaddrInet6{
+		Addr:   addr.As16(),
+		Port:   int(ap.Port()),
+		ZoneId: uint32(zoneCache.index(addr.Zone())),
+	}
+	return sa, nil
+}
diff --git a/contrib/go/_std_1.19/src/net/lookup.go b/contrib/go/_std_1.19/src/net/lookup.go
new file mode 100644
index 0000000000..7f3d20126c
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/lookup.go
@@ -0,0 +1,893 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+	"context"
+	"internal/nettrace"
+	"internal/singleflight"
+	"net/netip"
+	"sync"
+
+	"golang.org/x/net/dns/dnsmessage"
+)
+
+// protocols contains minimal mappings between internet protocol
+// names and numbers for platforms that don't have a complete list of
+// protocol numbers.
+//
+// See https://www.iana.org/assignments/protocol-numbers
+//
+// On Unix, this map is augmented by readProtocols via lookupProtocol.
+var protocols = map[string]int{
+	"icmp":      1,
+	"igmp":      2,
+	"tcp":       6,
+	"udp":       17,
+	"ipv6-icmp": 58,
+}
+
+// services contains minimal mappings between services names and port
+// numbers for platforms that don't have a complete list of port numbers.
+//
+// See https://www.iana.org/assignments/service-names-port-numbers
+//
+// On Unix, this map is augmented by readServices via goLookupPort.
+var services = map[string]map[string]int{
+	"udp": {
+		"domain": 53,
+	},
+	"tcp": {
+		"ftp":    21,
+		"ftps":   990,
+		"gopher": 70, // ʕ◔ϖ◔ʔ
+		"http":   80,
+		"https":  443,
+		"imap2":  143,
+		"imap3":  220,
+		"imaps":  993,
+		"pop3":   110,
+		"pop3s":  995,
+		"smtp":   25,
+		"ssh":    22,
+		"telnet": 23,
+	},
+}
+
+// dnsWaitGroup can be used by tests to wait for all DNS goroutines to
+// complete. This avoids races on the test hooks.
+var dnsWaitGroup sync.WaitGroup
+
+const maxProtoLength = len("RSVP-E2E-IGNORE") + 10 // with room to grow
+
+func lookupProtocolMap(name string) (int, error) {
+	var lowerProtocol [maxProtoLength]byte
+	n := copy(lowerProtocol[:], name)
+	lowerASCIIBytes(lowerProtocol[:n])
+	proto, found := protocols[string(lowerProtocol[:n])]
+	if !found || n != len(name) {
+		return 0, &AddrError{Err: "unknown IP protocol specified", Addr: name}
+	}
+	return proto, nil
+}
+
+// maxPortBufSize is the longest reasonable name of a service
+// (non-numeric port).
+// Currently the longest known IANA-unregistered name is
+// "mobility-header", so we use that length, plus some slop in case
+// something longer is added in the future.
+const maxPortBufSize = len("mobility-header") + 10
+
+func lookupPortMap(network, service string) (port int, error error) {
+	switch network {
+	case "tcp4", "tcp6":
+		network = "tcp"
+	case "udp4", "udp6":
+		network = "udp"
+	}
+
+	if m, ok := services[network]; ok {
+		var lowerService [maxPortBufSize]byte
+		n := copy(lowerService[:], service)
+		lowerASCIIBytes(lowerService[:n])
+		if port, ok := m[string(lowerService[:n])]; ok && n == len(service) {
+			return port, nil
+		}
+	}
+	return 0, &AddrError{Err: "unknown port", Addr: network + "/" + service}
+}
+
+// ipVersion returns the provided network's IP version: '4', '6' or 0
+// if network does not end in a '4' or '6' byte.
+func ipVersion(network string) byte {
+	if network == "" {
+		return 0
+	}
+	n := network[len(network)-1]
+	if n != '4' && n != '6' {
+		n = 0
+	}
+	return n
+}
+
+// DefaultResolver is the resolver used by the package-level Lookup
+// functions and by Dialers without a specified Resolver.
+var DefaultResolver = &Resolver{}
+
+// A Resolver looks up names and numbers.
+//
+// A nil *Resolver is equivalent to a zero Resolver.
+type Resolver struct {
+	// PreferGo controls whether Go's built-in DNS resolver is preferred
+	// on platforms where it's available. It is equivalent to setting
+	// GODEBUG=netdns=go, but scoped to just this resolver.
+	PreferGo bool
+
+	// StrictErrors controls the behavior of temporary errors
+	// (including timeout, socket errors, and SERVFAIL) when using
+	// Go's built-in resolver. For a query composed of multiple
+	// sub-queries (such as an A+AAAA address lookup, or walking the
+	// DNS search list), this option causes such errors to abort the
+	// whole query instead of returning a partial result. This is
+	// not enabled by default because it may affect compatibility
+	// with resolvers that process AAAA queries incorrectly.
+	StrictErrors bool
+
+	// Dial optionally specifies an alternate dialer for use by
+	// Go's built-in DNS resolver to make TCP and UDP connections
+	// to DNS services. The host in the address parameter will
+	// always be a literal IP address and not a host name, and the
+	// port in the address parameter will be a literal port number
+	// and not a service name.
+	// If the Conn returned is also a PacketConn, sent and received DNS
+	// messages must adhere to RFC 1035 section 4.2.1, "UDP usage".
+	// Otherwise, DNS messages transmitted over Conn must adhere
+	// to RFC 7766 section 5, "Transport Protocol Selection".
+	// If nil, the default dialer is used.
+	Dial func(ctx context.Context, network, address string) (Conn, error)
+
+	// lookupGroup merges LookupIPAddr calls together for lookups for the same
+	// host. The lookupGroup key is the LookupIPAddr.host argument.
+	// The return values are ([]IPAddr, error).
+	lookupGroup singleflight.Group
+
+	// TODO(bradfitz): optional interface impl override hook
+	// TODO(bradfitz): Timeout time.Duration?
+}
+
+func (r *Resolver) preferGo() bool     { return r != nil && r.PreferGo }
+func (r *Resolver) strictErrors() bool { return r != nil && r.StrictErrors }
+
+func (r *Resolver) getLookupGroup() *singleflight.Group {
+	if r == nil {
+		return &DefaultResolver.lookupGroup
+	}
+	return &r.lookupGroup
+}
+
+// LookupHost looks up the given host using the local resolver.
+// It returns a slice of that host's addresses.
+//
+// LookupHost uses context.Background internally; to specify the context, use
+// Resolver.LookupHost.
+func LookupHost(host string) (addrs []string, err error) {
+	return DefaultResolver.LookupHost(context.Background(), host)
+}
+
+// LookupHost looks up the given host using the local resolver.
+// It returns a slice of that host's addresses.
+func (r *Resolver) LookupHost(ctx context.Context, host string) (addrs []string, err error) {
+	// Make sure that no matter what we do later, host=="" is rejected.
+	// parseIP, for example, does accept empty strings.
+	if host == "" {
+		return nil, &DNSError{Err: errNoSuchHost.Error(), Name: host, IsNotFound: true}
+	}
+	if ip, _ := parseIPZone(host); ip != nil {
+		return []string{host}, nil
+	}
+	return r.lookupHost(ctx, host)
+}
+
+// LookupIP looks up host using the local resolver.
+// It returns a slice of that host's IPv4 and IPv6 addresses.
+func LookupIP(host string) ([]IP, error) {
+	addrs, err := DefaultResolver.LookupIPAddr(context.Background(), host)
+	if err != nil {
+		return nil, err
+	}
+	ips := make([]IP, len(addrs))
+	for i, ia := range addrs {
+		ips[i] = ia.IP
+	}
+	return ips, nil
+}
+
+// LookupIPAddr looks up host using the local resolver.
+// It returns a slice of that host's IPv4 and IPv6 addresses.
+func (r *Resolver) LookupIPAddr(ctx context.Context, host string) ([]IPAddr, error) {
+	return r.lookupIPAddr(ctx, "ip", host)
+}
+
+// LookupIP looks up host for the given network using the local resolver.
+// It returns a slice of that host's IP addresses of the type specified by
+// network.
+// network must be one of "ip", "ip4" or "ip6".
+func (r *Resolver) LookupIP(ctx context.Context, network, host string) ([]IP, error) {
+	afnet, _, err := parseNetwork(ctx, network, false)
+	if err != nil {
+		return nil, err
+	}
+	switch afnet {
+	case "ip", "ip4", "ip6":
+	default:
+		return nil, UnknownNetworkError(network)
+	}
+	addrs, err := r.internetAddrList(ctx, afnet, host)
+	if err != nil {
+		return nil, err
+	}
+	ips := make([]IP, 0, len(addrs))
+	for _, addr := range addrs {
+		ips = append(ips, addr.(*IPAddr).IP)
+	}
+	return ips, nil
+}
+
+// LookupNetIP looks up host using the local resolver.
+// It returns a slice of that host's IP addresses of the type specified by
+// network.
+// The network must be one of "ip", "ip4" or "ip6".
+func (r *Resolver) LookupNetIP(ctx context.Context, network, host string) ([]netip.Addr, error) {
+	// TODO(bradfitz): make this efficient, making the internal net package
+	// type throughout be netip.Addr and only converting to the net.IP slice
+	// version at the edge. But for now (2021-10-20), this is a wrapper around
+	// the old way.
+	ips, err := r.LookupIP(ctx, network, host)
+	if err != nil {
+		return nil, err
+	}
+	ret := make([]netip.Addr, 0, len(ips))
+	for _, ip := range ips {
+		if a, ok := netip.AddrFromSlice(ip); ok {
+			ret = append(ret, a)
+		}
+	}
+	return ret, nil
+}
+
+// onlyValuesCtx is a context that uses an underlying context
+// for value lookup if the underlying context hasn't yet expired.
+type onlyValuesCtx struct {
+	context.Context
+	lookupValues context.Context
+}
+
+var _ context.Context = (*onlyValuesCtx)(nil)
+
+// Value performs a lookup if the original context hasn't expired.
+func (ovc *onlyValuesCtx) Value(key any) any {
+	select {
+	case <-ovc.lookupValues.Done():
+		return nil
+	default:
+		return ovc.lookupValues.Value(key)
+	}
+}
+
+// withUnexpiredValuesPreserved returns a context.Context that only uses lookupCtx
+// for its values, otherwise it is never canceled and has no deadline.
+// If the lookup context expires, any looked up values will return nil.
+// See Issue 28600.
+func withUnexpiredValuesPreserved(lookupCtx context.Context) context.Context {
+	return &onlyValuesCtx{Context: context.Background(), lookupValues: lookupCtx}
+}
+
+// lookupIPAddr looks up host using the local resolver and particular network.
+// It returns a slice of that host's IPv4 and IPv6 addresses.
+func (r *Resolver) lookupIPAddr(ctx context.Context, network, host string) ([]IPAddr, error) {
+	// Make sure that no matter what we do later, host=="" is rejected.
+	// parseIPZone, for example, does accept empty strings.
+	if host == "" {
+		return nil, &DNSError{Err: errNoSuchHost.Error(), Name: host, IsNotFound: true}
+	}
+	if ip, zone := parseIPZone(host); ip != nil {
+		return []IPAddr{{IP: ip, Zone: zone}}, nil
+	}
+	trace, _ := ctx.Value(nettrace.TraceKey{}).(*nettrace.Trace)
+	if trace != nil && trace.DNSStart != nil {
+		trace.DNSStart(host)
+	}
+	// The underlying resolver func is lookupIP by default but it
+	// can be overridden by tests. This is needed by net/http, so it
+	// uses a context key instead of unexported variables.
+	resolverFunc := r.lookupIP
+	if alt, _ := ctx.Value(nettrace.LookupIPAltResolverKey{}).(func(context.Context, string, string) ([]IPAddr, error)); alt != nil {
+		resolverFunc = alt
+	}
+
+	// We don't want a cancellation of ctx to affect the
+	// lookupGroup operation. Otherwise if our context gets
+	// canceled it might cause an error to be returned to a lookup
+	// using a completely different context. However we need to preserve
+	// only the values in context. See Issue 28600.
+	lookupGroupCtx, lookupGroupCancel := context.WithCancel(withUnexpiredValuesPreserved(ctx))
+
+	lookupKey := network + "\000" + host
+	dnsWaitGroup.Add(1)
+	ch, called := r.getLookupGroup().DoChan(lookupKey, func() (any, error) {
+		defer dnsWaitGroup.Done()
+		return testHookLookupIP(lookupGroupCtx, resolverFunc, network, host)
+	})
+	if !called {
+		dnsWaitGroup.Done()
+	}
+
+	select {
+	case <-ctx.Done():
+		// Our context was canceled. If we are the only
+		// goroutine looking up this key, then drop the key
+		// from the lookupGroup and cancel the lookup.
+		// If there are other goroutines looking up this key,
+		// let the lookup continue uncanceled, and let later
+		// lookups with the same key share the result.
+		// See issues 8602, 20703, 22724.
+		if r.getLookupGroup().ForgetUnshared(lookupKey) {
+			lookupGroupCancel()
+		} else {
+			go func() {
+				<-ch
+				lookupGroupCancel()
+			}()
+		}
+		ctxErr := ctx.Err()
+		err := &DNSError{
+			Err:       mapErr(ctxErr).Error(),
+			Name:      host,
+			IsTimeout: ctxErr == context.DeadlineExceeded,
+		}
+		if trace != nil && trace.DNSDone != nil {
+			trace.DNSDone(nil, false, err)
+		}
+		return nil, err
+	case r := <-ch:
+		lookupGroupCancel()
+		err := r.Err
+		if err != nil {
+			if _, ok := err.(*DNSError); !ok {
+				isTimeout := false
+				if err == context.DeadlineExceeded {
+					isTimeout = true
+				} else if terr, ok := err.(timeout); ok {
+					isTimeout = terr.Timeout()
+				}
+				err = &DNSError{
+					Err:       err.Error(),
+					Name:      host,
+					IsTimeout: isTimeout,
+				}
+			}
+		}
+		if trace != nil && trace.DNSDone != nil {
+			addrs, _ := r.Val.([]IPAddr)
+			trace.DNSDone(ipAddrsEface(addrs), r.Shared, err)
+		}
+		return lookupIPReturn(r.Val, err, r.Shared)
+	}
+}
+
+// lookupIPReturn turns the return values from singleflight.Do into
+// the return values from LookupIP.
+func lookupIPReturn(addrsi any, err error, shared bool) ([]IPAddr, error) {
+	if err != nil {
+		return nil, err
+	}
+	addrs := addrsi.([]IPAddr)
+	if shared {
+		clone := make([]IPAddr, len(addrs))
+		copy(clone, addrs)
+		addrs = clone
+	}
+	return addrs, nil
+}
+
+// ipAddrsEface returns an empty interface slice of addrs.
+func ipAddrsEface(addrs []IPAddr) []any {
+	s := make([]any, len(addrs))
+	for i, v := range addrs {
+		s[i] = v
+	}
+	return s
+}
+
+// LookupPort looks up the port for the given network and service.
+//
+// LookupPort uses context.Background internally; to specify the context, use
+// Resolver.LookupPort.
+func LookupPort(network, service string) (port int, err error) {
+	return DefaultResolver.LookupPort(context.Background(), network, service)
+}
+
+// LookupPort looks up the port for the given network and service.
+func (r *Resolver) LookupPort(ctx context.Context, network, service string) (port int, err error) {
+	port, needsLookup := parsePort(service)
+	if needsLookup {
+		switch network {
+		case "tcp", "tcp4", "tcp6", "udp", "udp4", "udp6":
+		case "": // a hint wildcard for Go 1.0 undocumented behavior
+			network = "ip"
+		default:
+			return 0, &AddrError{Err: "unknown network", Addr: network}
+		}
+		port, err = r.lookupPort(ctx, network, service)
+		if err != nil {
+			return 0, err
+		}
+	}
+	if 0 > port || port > 65535 {
+		return 0, &AddrError{Err: "invalid port", Addr: service}
+	}
+	return port, nil
+}
+
+// LookupCNAME returns the canonical name for the given host.
+// Callers that do not care about the canonical name can call
+// LookupHost or LookupIP directly; both take care of resolving
+// the canonical name as part of the lookup.
+//
+// A canonical name is the final name after following zero
+// or more CNAME records.
+// LookupCNAME does not return an error if host does not
+// contain DNS "CNAME" records, as long as host resolves to
+// address records.
+//
+// The returned canonical name is validated to be a properly
+// formatted presentation-format domain name.
+//
+// LookupCNAME uses context.Background internally; to specify the context, use
+// Resolver.LookupCNAME.
+func LookupCNAME(host string) (cname string, err error) {
+	return DefaultResolver.LookupCNAME(context.Background(), host)
+}
+
+// LookupCNAME returns the canonical name for the given host.
+// Callers that do not care about the canonical name can call
+// LookupHost or LookupIP directly; both take care of resolving
+// the canonical name as part of the lookup.
+//
+// A canonical name is the final name after following zero
+// or more CNAME records.
+// LookupCNAME does not return an error if host does not
+// contain DNS "CNAME" records, as long as host resolves to
+// address records.
+//
+// The returned canonical name is validated to be a properly
+// formatted presentation-format domain name.
+func (r *Resolver) LookupCNAME(ctx context.Context, host string) (string, error) {
+	cname, err := r.lookupCNAME(ctx, host)
+	if err != nil {
+		return "", err
+	}
+	if !isDomainName(cname) {
+		return "", &DNSError{Err: errMalformedDNSRecordsDetail, Name: host}
+	}
+	return cname, nil
+}
+
+// LookupSRV tries to resolve an SRV query of the given service,
+// protocol, and domain name. The proto is "tcp" or "udp".
+// The returned records are sorted by priority and randomized
+// by weight within a priority.
+//
+// LookupSRV constructs the DNS name to look up following RFC 2782.
+// That is, it looks up _service._proto.name. To accommodate services
+// publishing SRV records under non-standard names, if both service
+// and proto are empty strings, LookupSRV looks up name directly.
+//
+// The returned service names are validated to be properly
+// formatted presentation-format domain names. If the response contains
+// invalid names, those records are filtered out and an error
+// will be returned alongside the remaining results, if any.
+func LookupSRV(service, proto, name string) (cname string, addrs []*SRV, err error) {
+	return DefaultResolver.LookupSRV(context.Background(), service, proto, name)
+}
+
+// LookupSRV tries to resolve an SRV query of the given service,
+// protocol, and domain name. The proto is "tcp" or "udp".
+// The returned records are sorted by priority and randomized
+// by weight within a priority.
+//
+// LookupSRV constructs the DNS name to look up following RFC 2782.
+// That is, it looks up _service._proto.name. To accommodate services
+// publishing SRV records under non-standard names, if both service
+// and proto are empty strings, LookupSRV looks up name directly.
+//
+// The returned service names are validated to be properly
+// formatted presentation-format domain names. If the response contains
+// invalid names, those records are filtered out and an error
+// will be returned alongside the remaining results, if any.
+func (r *Resolver) LookupSRV(ctx context.Context, service, proto, name string) (string, []*SRV, error) {
+	cname, addrs, err := r.lookupSRV(ctx, service, proto, name)
+	if err != nil {
+		return "", nil, err
+	}
+	if cname != "" && !isDomainName(cname) {
+		return "", nil, &DNSError{Err: "SRV header name is invalid", Name: name}
+	}
+	filteredAddrs := make([]*SRV, 0, len(addrs))
+	for _, addr := range addrs {
+		if addr == nil {
+			continue
+		}
+		if !isDomainName(addr.Target) {
+			continue
+		}
+		filteredAddrs = append(filteredAddrs, addr)
+	}
+	if len(addrs) != len(filteredAddrs) {
+		return cname, filteredAddrs, &DNSError{Err: errMalformedDNSRecordsDetail, Name: name}
+	}
+	return cname, filteredAddrs, nil
+}
+
+// LookupMX returns the DNS MX records for the given domain name sorted by preference.
+//
+// The returned mail server names are validated to be properly
+// formatted presentation-format domain names. If the response contains
+// invalid names, those records are filtered out and an error
+// will be returned alongside the remaining results, if any.
+//
+// LookupMX uses context.Background internally; to specify the context, use
+// Resolver.LookupMX.
+func LookupMX(name string) ([]*MX, error) {
+	return DefaultResolver.LookupMX(context.Background(), name)
+}
+
+// LookupMX returns the DNS MX records for the given domain name sorted by preference.
+//
+// The returned mail server names are validated to be properly
+// formatted presentation-format domain names. If the response contains
+// invalid names, those records are filtered out and an error
+// will be returned alongside the remaining results, if any.
+func (r *Resolver) LookupMX(ctx context.Context, name string) ([]*MX, error) {
+	records, err := r.lookupMX(ctx, name)
+	if err != nil {
+		return nil, err
+	}
+	filteredMX := make([]*MX, 0, len(records))
+	for _, mx := range records {
+		if mx == nil {
+			continue
+		}
+		if !isDomainName(mx.Host) {
+			continue
+		}
+		filteredMX = append(filteredMX, mx)
+	}
+	if len(records) != len(filteredMX) {
+		return filteredMX, &DNSError{Err: errMalformedDNSRecordsDetail, Name: name}
+	}
+	return filteredMX, nil
+}
+
+// LookupNS returns the DNS NS records for the given domain name.
+//
+// The returned name server names are validated to be properly
+// formatted presentation-format domain names. If the response contains
+// invalid names, those records are filtered out and an error
+// will be returned alongside the remaining results, if any.
+//
+// LookupNS uses context.Background internally; to specify the context, use
+// Resolver.LookupNS.
+func LookupNS(name string) ([]*NS, error) {
+	return DefaultResolver.LookupNS(context.Background(), name)
+}
+
+// LookupNS returns the DNS NS records for the given domain name.
+//
+// The returned name server names are validated to be properly
+// formatted presentation-format domain names. If the response contains
+// invalid names, those records are filtered out and an error
+// will be returned alongside the remaining results, if any.
+func (r *Resolver) LookupNS(ctx context.Context, name string) ([]*NS, error) {
+	records, err := r.lookupNS(ctx, name)
+	if err != nil {
+		return nil, err
+	}
+	filteredNS := make([]*NS, 0, len(records))
+	for _, ns := range records {
+		if ns == nil {
+			continue
+		}
+		if !isDomainName(ns.Host) {
+			continue
+		}
+		filteredNS = append(filteredNS, ns)
+	}
+	if len(records) != len(filteredNS) {
+		return filteredNS, &DNSError{Err: errMalformedDNSRecordsDetail, Name: name}
+	}
+	return filteredNS, nil
+}
+
+// LookupTXT returns the DNS TXT records for the given domain name.
+//
+// LookupTXT uses context.Background internally; to specify the context, use
+// Resolver.LookupTXT.
+func LookupTXT(name string) ([]string, error) {
+	return DefaultResolver.lookupTXT(context.Background(), name)
+}
+
+// LookupTXT returns the DNS TXT records for the given domain name.
+func (r *Resolver) LookupTXT(ctx context.Context, name string) ([]string, error) {
+	return r.lookupTXT(ctx, name)
+}
+
+// LookupAddr performs a reverse lookup for the given address, returning a list
+// of names mapping to that address.
+//
+// The returned names are validated to be properly formatted presentation-format
+// domain names. If the response contains invalid names, those records are filtered
+// out and an error will be returned alongside the remaining results, if any.
+//
+// When using the host C library resolver, at most one result will be
+// returned. To bypass the host resolver, use a custom Resolver.
+//
+// LookupAddr uses context.Background internally; to specify the context, use
+// Resolver.LookupAddr.
+func LookupAddr(addr string) (names []string, err error) {
+	return DefaultResolver.LookupAddr(context.Background(), addr)
+}
+
+// LookupAddr performs a reverse lookup for the given address, returning a list
+// of names mapping to that address.
+//
+// The returned names are validated to be properly formatted presentation-format
+// domain names. If the response contains invalid names, those records are filtered
+// out and an error will be returned alongside the remaining results, if any.
+func (r *Resolver) LookupAddr(ctx context.Context, addr string) ([]string, error) {
+	names, err := r.lookupAddr(ctx, addr)
+	if err != nil {
+		return nil, err
+	}
+	filteredNames := make([]string, 0, len(names))
+	for _, name := range names {
+		if isDomainName(name) {
+			filteredNames = append(filteredNames, name)
+		}
+	}
+	if len(names) != len(filteredNames) {
+		return filteredNames, &DNSError{Err: errMalformedDNSRecordsDetail, Name: addr}
+	}
+	return filteredNames, nil
+}
+
+// errMalformedDNSRecordsDetail is the DNSError detail which is returned when a Resolver.Lookup...
+// method receives DNS records which contain invalid DNS names. This may be returned alongside
+// results which have had the malformed records filtered out.
+var errMalformedDNSRecordsDetail = "DNS response contained records which contain invalid names"
+
+// dial makes a new connection to the provided server (which must be
+// an IP address) with the provided network type, using either r.Dial
+// (if both r and r.Dial are non-nil) or else Dialer.DialContext.
+func (r *Resolver) dial(ctx context.Context, network, server string) (Conn, error) {
+	// Calling Dial here is scary -- we have to be sure not to
+	// dial a name that will require a DNS lookup, or Dial will
+	// call back here to translate it. The DNS config parser has
+	// already checked that all the cfg.servers are IP
+	// addresses, which Dial will use without a DNS lookup.
+	var c Conn
+	var err error
+	if r != nil && r.Dial != nil {
+		c, err = r.Dial(ctx, network, server)
+	} else {
+		var d Dialer
+		c, err = d.DialContext(ctx, network, server)
+	}
+	if err != nil {
+		return nil, mapErr(err)
+	}
+	return c, nil
+}
+
+// goLookupSRV returns the SRV records for a target name, built either
+// from its component service ("sip"), protocol ("tcp"), and name
+// ("example.com."), or from name directly (if service and proto are
+// both empty).
+//
+// In either case, the returned target name ("_sip._tcp.example.com.")
+// is also returned on success.
+//
+// The records are sorted by weight.
+func (r *Resolver) goLookupSRV(ctx context.Context, service, proto, name string) (target string, srvs []*SRV, err error) {
+	if service == "" && proto == "" {
+		target = name
+	} else {
+		target = "_" + service + "._" + proto + "." + name
+	}
+	p, server, err := r.lookup(ctx, target, dnsmessage.TypeSRV)
+	if err != nil {
+		return "", nil, err
+	}
+	var cname dnsmessage.Name
+	for {
+		h, err := p.AnswerHeader()
+		if err == dnsmessage.ErrSectionDone {
+			break
+		}
+		if err != nil {
+			return "", nil, &DNSError{
+				Err:    "cannot unmarshal DNS message",
+				Name:   name,
+				Server: server,
+			}
+		}
+		if h.Type != dnsmessage.TypeSRV {
+			if err := p.SkipAnswer(); err != nil {
+				return "", nil, &DNSError{
+					Err:    "cannot unmarshal DNS message",
+					Name:   name,
+					Server: server,
+				}
+			}
+			continue
+		}
+		if cname.Length == 0 && h.Name.Length != 0 {
+			cname = h.Name
+		}
+		srv, err := p.SRVResource()
+		if err != nil {
+			return "", nil, &DNSError{
+				Err:    "cannot unmarshal DNS message",
+				Name:   name,
+				Server: server,
+			}
+		}
+		srvs = append(srvs, &SRV{Target: srv.Target.String(), Port: srv.Port, Priority: srv.Priority, Weight: srv.Weight})
+	}
+	byPriorityWeight(srvs).sort()
+	return cname.String(), srvs, nil
+}
+
+// goLookupMX returns the MX records for name.
+func (r *Resolver) goLookupMX(ctx context.Context, name string) ([]*MX, error) {
+	p, server, err := r.lookup(ctx, name, dnsmessage.TypeMX)
+	if err != nil {
+		return nil, err
+	}
+	var mxs []*MX
+	for {
+		h, err := p.AnswerHeader()
+		if err == dnsmessage.ErrSectionDone {
+			break
+		}
+		if err != nil {
+			return nil, &DNSError{
+				Err:    "cannot unmarshal DNS message",
+				Name:   name,
+				Server: server,
+			}
+		}
+		if h.Type != dnsmessage.TypeMX {
+			if err := p.SkipAnswer(); err != nil {
+				return nil, &DNSError{
+					Err:    "cannot unmarshal DNS message",
+					Name:   name,
+					Server: server,
+				}
+			}
+			continue
+		}
+		mx, err := p.MXResource()
+		if err != nil {
+			return nil, &DNSError{
+				Err:    "cannot unmarshal DNS message",
+				Name:   name,
+				Server: server,
+			}
+		}
+		mxs = append(mxs, &MX{Host: mx.MX.String(), Pref: mx.Pref})
+
+	}
+	byPref(mxs).sort()
+	return mxs, nil
+}
+
+// goLookupNS returns the NS records for name.
+func (r *Resolver) goLookupNS(ctx context.Context, name string) ([]*NS, error) {
+	p, server, err := r.lookup(ctx, name, dnsmessage.TypeNS)
+	if err != nil {
+		return nil, err
+	}
+	var nss []*NS
+	for {
+		h, err := p.AnswerHeader()
+		if err == dnsmessage.ErrSectionDone {
+			break
+		}
+		if err != nil {
+			return nil, &DNSError{
+				Err:    "cannot unmarshal DNS message",
+				Name:   name,
+				Server: server,
+			}
+		}
+		if h.Type != dnsmessage.TypeNS {
+			if err := p.SkipAnswer(); err != nil {
+				return nil, &DNSError{
+					Err:    "cannot unmarshal DNS message",
+					Name:   name,
+					Server: server,
+				}
+			}
+			continue
+		}
+		ns, err := p.NSResource()
+		if err != nil {
+			return nil, &DNSError{
+				Err:    "cannot unmarshal DNS message",
+				Name:   name,
+				Server: server,
+			}
+		}
+		nss = append(nss, &NS{Host: ns.NS.String()})
+	}
+	return nss, nil
+}
+
+// goLookupTXT returns the TXT records from name.
+func (r *Resolver) goLookupTXT(ctx context.Context, name string) ([]string, error) {
+	p, server, err := r.lookup(ctx, name, dnsmessage.TypeTXT)
+	if err != nil {
+		return nil, err
+	}
+	var txts []string
+	for {
+		h, err := p.AnswerHeader()
+		if err == dnsmessage.ErrSectionDone {
+			break
+		}
+		if err != nil {
+			return nil, &DNSError{
+				Err:    "cannot unmarshal DNS message",
+				Name:   name,
+				Server: server,
+			}
+		}
+		if h.Type != dnsmessage.TypeTXT {
+			if err := p.SkipAnswer(); err != nil {
+				return nil, &DNSError{
+					Err:    "cannot unmarshal DNS message",
+					Name:   name,
+					Server: server,
+				}
+			}
+			continue
+		}
+		txt, err := p.TXTResource()
+		if err != nil {
+			return nil, &DNSError{
+				Err:    "cannot unmarshal DNS message",
+				Name:   name,
+				Server: server,
+			}
+		}
+		// Multiple strings in one TXT record need to be
+		// concatenated without separator to be consistent
+		// with previous Go resolver.
+		n := 0
+		for _, s := range txt.TXT {
+			n += len(s)
+		}
+		txtJoin := make([]byte, 0, n)
+		for _, s := range txt.TXT {
+			txtJoin = append(txtJoin, s...)
+		}
+		if len(txts) == 0 {
+			txts = make([]string, 0, 1)
+		}
+		txts = append(txts, string(txtJoin))
+	}
+	return txts, nil
+}
diff --git a/contrib/go/_std_1.19/src/net/lookup_unix.go b/contrib/go/_std_1.19/src/net/lookup_unix.go
new file mode 100644
index 0000000000..4b885e938a
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/lookup_unix.go
@@ -0,0 +1,156 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix
+
+package net
+
+import (
+	"context"
+	"internal/bytealg"
+	"sync"
+	"syscall"
+)
+
+var onceReadProtocols sync.Once
+
+// readProtocols loads contents of /etc/protocols into protocols map
+// for quick access.
+func readProtocols() {
+	file, err := open("/etc/protocols")
+	if err != nil {
+		return
+	}
+	defer file.close()
+
+	for line, ok := file.readLine(); ok; line, ok = file.readLine() {
+		// tcp    6   TCP    # transmission control protocol
+		if i := bytealg.IndexByteString(line, '#'); i >= 0 {
+			line = line[0:i]
+		}
+		f := getFields(line)
+		if len(f) < 2 {
+			continue
+		}
+		if proto, _, ok := dtoi(f[1]); ok {
+			if _, ok := protocols[f[0]]; !ok {
+				protocols[f[0]] = proto
+			}
+			for _, alias := range f[2:] {
+				if _, ok := protocols[alias]; !ok {
+					protocols[alias] = proto
+				}
+			}
+		}
+	}
+}
+
+// lookupProtocol looks up IP protocol name in /etc/protocols and
+// returns correspondent protocol number.
+func lookupProtocol(_ context.Context, name string) (int, error) {
+	onceReadProtocols.Do(readProtocols)
+	return lookupProtocolMap(name)
+}
+
+func (r *Resolver) lookupHost(ctx context.Context, host string) (addrs []string, err error) {
+	order := systemConf().hostLookupOrder(r, host)
+	if !r.preferGo() && order == hostLookupCgo {
+		if addrs, err, ok := cgoLookupHost(ctx, host); ok {
+			return addrs, err
+		}
+		// cgo not available (or netgo); fall back to Go's DNS resolver
+		order = hostLookupFilesDNS
+	}
+	return r.goLookupHostOrder(ctx, host, order)
+}
+
+func (r *Resolver) lookupIP(ctx context.Context, network, host string) (addrs []IPAddr, err error) {
+	if r.preferGo() {
+		return r.goLookupIP(ctx, network, host)
+	}
+	order := systemConf().hostLookupOrder(r, host)
+	if order == hostLookupCgo {
+		if addrs, err, ok := cgoLookupIP(ctx, network, host); ok {
+			return addrs, err
+		}
+		// cgo not available (or netgo); fall back to Go's DNS resolver
+		order = hostLookupFilesDNS
+	}
+	ips, _, err := r.goLookupIPCNAMEOrder(ctx, network, host, order)
+	return ips, err
+}
+
+func (r *Resolver) lookupPort(ctx context.Context, network, service string) (int, error) {
+	if !r.preferGo() && systemConf().canUseCgo() {
+		if port, err, ok := cgoLookupPort(ctx, network, service); ok {
+			if err != nil {
+				// Issue 18213: if cgo fails, first check to see whether we
+				// have the answer baked-in to the net package.
+				if port, err := goLookupPort(network, service); err == nil {
+					return port, nil
+				}
+			}
+			return port, err
+		}
+	}
+	return goLookupPort(network, service)
+}
+
+func (r *Resolver) lookupCNAME(ctx context.Context, name string) (string, error) {
+	if !r.preferGo() && systemConf().canUseCgo() {
+		if cname, err, ok := cgoLookupCNAME(ctx, name); ok {
+			return cname, err
+		}
+	}
+	return r.goLookupCNAME(ctx, name)
+}
+
+func (r *Resolver) lookupSRV(ctx context.Context, service, proto, name string) (string, []*SRV, error) {
+	return r.goLookupSRV(ctx, service, proto, name)
+}
+
+func (r *Resolver) lookupMX(ctx context.Context, name string) ([]*MX, error) {
+	return r.goLookupMX(ctx, name)
+}
+
+func (r *Resolver) lookupNS(ctx context.Context, name string) ([]*NS, error) {
+	return r.goLookupNS(ctx, name)
+}
+
+func (r *Resolver) lookupTXT(ctx context.Context, name string) ([]string, error) {
+	return r.goLookupTXT(ctx, name)
+}
+
+func (r *Resolver) lookupAddr(ctx context.Context, addr string) ([]string, error) {
+	if !r.preferGo() && systemConf().canUseCgo() {
+		if ptrs, err, ok := cgoLookupPTR(ctx, addr); ok {
+			return ptrs, err
+		}
+	}
+	return r.goLookupPTR(ctx, addr)
+}
+
+// concurrentThreadsLimit returns the number of threads we permit to
+// run concurrently doing DNS lookups via cgo. A DNS lookup may use a
+// file descriptor so we limit this to less than the number of
+// permitted open files. On some systems, notably Darwin, if
+// getaddrinfo is unable to open a file descriptor it simply returns
+// EAI_NONAME rather than a useful error. Limiting the number of
+// concurrent getaddrinfo calls to less than the permitted number of
+// file descriptors makes that error less likely. We don't bother to
+// apply the same limit to DNS lookups run directly from Go, because
+// there we will return a meaningful "too many open files" error.
+func concurrentThreadsLimit() int {
+	var rlim syscall.Rlimit
+	if err := syscall.Getrlimit(syscall.RLIMIT_NOFILE, &rlim); err != nil {
+		return 500
+	}
+	r := int(rlim.Cur)
+	if r > 500 {
+		r = 500
+	} else if r > 30 {
+		r -= 30
+	}
+	return r
+}
diff --git a/contrib/go/_std_1.19/src/net/mac.go b/contrib/go/_std_1.19/src/net/mac.go
new file mode 100644
index 0000000000..53d5b2dbf5
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/mac.go
@@ -0,0 +1,86 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+const hexDigit = "0123456789abcdef"
+
+// A HardwareAddr represents a physical hardware address.
+type HardwareAddr []byte
+
+func (a HardwareAddr) String() string {
+	if len(a) == 0 {
+		return ""
+	}
+	buf := make([]byte, 0, len(a)*3-1)
+	for i, b := range a {
+		if i > 0 {
+			buf = append(buf, ':')
+		}
+		buf = append(buf, hexDigit[b>>4])
+		buf = append(buf, hexDigit[b&0xF])
+	}
+	return string(buf)
+}
+
+// ParseMAC parses s as an IEEE 802 MAC-48, EUI-48, EUI-64, or a 20-octet
+// IP over InfiniBand link-layer address using one of the following formats:
+//
+//	00:00:5e:00:53:01
+//	02:00:5e:10:00:00:00:01
+//	00:00:00:00:fe:80:00:00:00:00:00:00:02:00:5e:10:00:00:00:01
+//	00-00-5e-00-53-01
+//	02-00-5e-10-00-00-00-01
+//	00-00-00-00-fe-80-00-00-00-00-00-00-02-00-5e-10-00-00-00-01
+//	0000.5e00.5301
+//	0200.5e10.0000.0001
+//	0000.0000.fe80.0000.0000.0000.0200.5e10.0000.0001
+func ParseMAC(s string) (hw HardwareAddr, err error) {
+	if len(s) < 14 {
+		goto error
+	}
+
+	if s[2] == ':' || s[2] == '-' {
+		if (len(s)+1)%3 != 0 {
+			goto error
+		}
+		n := (len(s) + 1) / 3
+		if n != 6 && n != 8 && n != 20 {
+			goto error
+		}
+		hw = make(HardwareAddr, n)
+		for x, i := 0, 0; i < n; i++ {
+			var ok bool
+			if hw[i], ok = xtoi2(s[x:], s[2]); !ok {
+				goto error
+			}
+			x += 3
+		}
+	} else if s[4] == '.' {
+		if (len(s)+1)%5 != 0 {
+			goto error
+		}
+		n := 2 * (len(s) + 1) / 5
+		if n != 6 && n != 8 && n != 20 {
+			goto error
+		}
+		hw = make(HardwareAddr, n)
+		for x, i := 0, 0; i < n; i += 2 {
+			var ok bool
+			if hw[i], ok = xtoi2(s[x:x+2], 0); !ok {
+				goto error
+			}
+			if hw[i+1], ok = xtoi2(s[x+2:], s[4]); !ok {
+				goto error
+			}
+			x += 5
+		}
+	} else {
+		goto error
+	}
+	return hw, nil
+
+error:
+	return nil, &AddrError{Err: "invalid MAC address", Addr: s}
+}
diff --git a/contrib/go/_std_1.19/src/net/net.go b/contrib/go/_std_1.19/src/net/net.go
new file mode 100644
index 0000000000..ff56c31c56
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/net.go
@@ -0,0 +1,771 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package net provides a portable interface for network I/O, including
+TCP/IP, UDP, domain name resolution, and Unix domain sockets.
+
+Although the package provides access to low-level networking
+primitives, most clients will need only the basic interface provided
+by the Dial, Listen, and Accept functions and the associated
+Conn and Listener interfaces. The crypto/tls package uses
+the same interfaces and similar Dial and Listen functions.
+
+The Dial function connects to a server:
+
+	conn, err := net.Dial("tcp", "golang.org:80")
+	if err != nil {
+		// handle error
+	}
+	fmt.Fprintf(conn, "GET / HTTP/1.0\r\n\r\n")
+	status, err := bufio.NewReader(conn).ReadString('\n')
+	// ...
+
+The Listen function creates servers:
+
+	ln, err := net.Listen("tcp", ":8080")
+	if err != nil {
+		// handle error
+	}
+	for {
+		conn, err := ln.Accept()
+		if err != nil {
+			// handle error
+		}
+		go handleConnection(conn)
+	}
+
+# Name Resolution
+
+The method for resolving domain names, whether indirectly with functions like Dial
+or directly with functions like LookupHost and LookupAddr, varies by operating system.
+
+On Unix systems, the resolver has two options for resolving names.
+It can use a pure Go resolver that sends DNS requests directly to the servers
+listed in /etc/resolv.conf, or it can use a cgo-based resolver that calls C
+library routines such as getaddrinfo and getnameinfo.
+
+By default the pure Go resolver is used, because a blocked DNS request consumes
+only a goroutine, while a blocked C call consumes an operating system thread.
+When cgo is available, the cgo-based resolver is used instead under a variety of
+conditions: on systems that do not let programs make direct DNS requests (OS X),
+when the LOCALDOMAIN environment variable is present (even if empty),
+when the RES_OPTIONS or HOSTALIASES environment variable is non-empty,
+when the ASR_CONFIG environment variable is non-empty (OpenBSD only),
+when /etc/resolv.conf or /etc/nsswitch.conf specify the use of features that the
+Go resolver does not implement, and when the name being looked up ends in .local
+or is an mDNS name.
+
+The resolver decision can be overridden by setting the netdns value of the
+GODEBUG environment variable (see package runtime) to go or cgo, as in:
+
+	export GODEBUG=netdns=go    # force pure Go resolver
+	export GODEBUG=netdns=cgo   # force native resolver (cgo, win32)
+
+The decision can also be forced while building the Go source tree
+by setting the netgo or netcgo build tag.
+
+A numeric netdns setting, as in GODEBUG=netdns=1, causes the resolver
+to print debugging information about its decisions.
+To force a particular resolver while also printing debugging information,
+join the two settings by a plus sign, as in GODEBUG=netdns=go+1.
+
+On Plan 9, the resolver always accesses /net/cs and /net/dns.
+
+On Windows, in Go 1.18.x and earlier, the resolver always used C
+library functions, such as GetAddrInfo and DnsQuery.
+*/
+package net
+
+import (
+	"context"
+	"errors"
+	"internal/poll"
+	"io"
+	"os"
+	"sync"
+	"syscall"
+	"time"
+)
+
+// netGo and netCgo contain the state of the build tags used
+// to build this binary, and whether cgo is available.
+// conf.go mirrors these into conf for easier testing.
+var (
+	netGo  bool // set true in cgo_stub.go for build tag "netgo" (or no cgo)
+	netCgo bool // set true in conf_netcgo.go for build tag "netcgo"
+)
+
+// Addr represents a network end point address.
+//
+// The two methods Network and String conventionally return strings
+// that can be passed as the arguments to Dial, but the exact form
+// and meaning of the strings is up to the implementation.
+type Addr interface {
+	Network() string // name of the network (for example, "tcp", "udp")
+	String() string  // string form of address (for example, "192.0.2.1:25", "[2001:db8::1]:80")
+}
+
+// Conn is a generic stream-oriented network connection.
+//
+// Multiple goroutines may invoke methods on a Conn simultaneously.
+type Conn interface {
+	// Read reads data from the connection.
+	// Read can be made to time out and return an error after a fixed
+	// time limit; see SetDeadline and SetReadDeadline.
+	Read(b []byte) (n int, err error)
+
+	// Write writes data to the connection.
+	// Write can be made to time out and return an error after a fixed
+	// time limit; see SetDeadline and SetWriteDeadline.
+	Write(b []byte) (n int, err error)
+
+	// Close closes the connection.
+	// Any blocked Read or Write operations will be unblocked and return errors.
+	Close() error
+
+	// LocalAddr returns the local network address, if known.
+	LocalAddr() Addr
+
+	// RemoteAddr returns the remote network address, if known.
+	RemoteAddr() Addr
+
+	// SetDeadline sets the read and write deadlines associated
+	// with the connection. It is equivalent to calling both
+	// SetReadDeadline and SetWriteDeadline.
+	//
+	// A deadline is an absolute time after which I/O operations
+	// fail instead of blocking. The deadline applies to all future
+	// and pending I/O, not just the immediately following call to
+	// Read or Write. After a deadline has been exceeded, the
+	// connection can be refreshed by setting a deadline in the future.
+	//
+	// If the deadline is exceeded a call to Read or Write or to other
+	// I/O methods will return an error that wraps os.ErrDeadlineExceeded.
+	// This can be tested using errors.Is(err, os.ErrDeadlineExceeded).
+	// The error's Timeout method will return true, but note that there
+	// are other possible errors for which the Timeout method will
+	// return true even if the deadline has not been exceeded.
+	//
+	// An idle timeout can be implemented by repeatedly extending
+	// the deadline after successful Read or Write calls.
+	//
+	// A zero value for t means I/O operations will not time out.
+	SetDeadline(t time.Time) error
+
+	// SetReadDeadline sets the deadline for future Read calls
+	// and any currently-blocked Read call.
+	// A zero value for t means Read will not time out.
+	SetReadDeadline(t time.Time) error
+
+	// SetWriteDeadline sets the deadline for future Write calls
+	// and any currently-blocked Write call.
+	// Even if write times out, it may return n > 0, indicating that
+	// some of the data was successfully written.
+	// A zero value for t means Write will not time out.
+	SetWriteDeadline(t time.Time) error
+}
+
+type conn struct {
+	fd *netFD
+}
+
+func (c *conn) ok() bool { return c != nil && c.fd != nil }
+
+// Implementation of the Conn interface.
+
+// Read implements the Conn Read method.
+func (c *conn) Read(b []byte) (int, error) {
+	if !c.ok() {
+		return 0, syscall.EINVAL
+	}
+	n, err := c.fd.Read(b)
+	if err != nil && err != io.EOF {
+		err = &OpError{Op: "read", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+	}
+	return n, err
+}
+
+// Write implements the Conn Write method.
+func (c *conn) Write(b []byte) (int, error) {
+	if !c.ok() {
+		return 0, syscall.EINVAL
+	}
+	n, err := c.fd.Write(b)
+	if err != nil {
+		err = &OpError{Op: "write", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+	}
+	return n, err
+}
+
+// Close closes the connection.
+func (c *conn) Close() error {
+	if !c.ok() {
+		return syscall.EINVAL
+	}
+	err := c.fd.Close()
+	if err != nil {
+		err = &OpError{Op: "close", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+	}
+	return err
+}
+
+// LocalAddr returns the local network address.
+// The Addr returned is shared by all invocations of LocalAddr, so
+// do not modify it.
+func (c *conn) LocalAddr() Addr {
+	if !c.ok() {
+		return nil
+	}
+	return c.fd.laddr
+}
+
+// RemoteAddr returns the remote network address.
+// The Addr returned is shared by all invocations of RemoteAddr, so
+// do not modify it.
+func (c *conn) RemoteAddr() Addr {
+	if !c.ok() {
+		return nil
+	}
+	return c.fd.raddr
+}
+
+// SetDeadline implements the Conn SetDeadline method.
+func (c *conn) SetDeadline(t time.Time) error {
+	if !c.ok() {
+		return syscall.EINVAL
+	}
+	if err := c.fd.SetDeadline(t); err != nil {
+		return &OpError{Op: "set", Net: c.fd.net, Source: nil, Addr: c.fd.laddr, Err: err}
+	}
+	return nil
+}
+
+// SetReadDeadline implements the Conn SetReadDeadline method.
+func (c *conn) SetReadDeadline(t time.Time) error {
+	if !c.ok() {
+		return syscall.EINVAL
+	}
+	if err := c.fd.SetReadDeadline(t); err != nil {
+		return &OpError{Op: "set", Net: c.fd.net, Source: nil, Addr: c.fd.laddr, Err: err}
+	}
+	return nil
+}
+
+// SetWriteDeadline implements the Conn SetWriteDeadline method.
+func (c *conn) SetWriteDeadline(t time.Time) error {
+	if !c.ok() {
+		return syscall.EINVAL
+	}
+	if err := c.fd.SetWriteDeadline(t); err != nil {
+		return &OpError{Op: "set", Net: c.fd.net, Source: nil, Addr: c.fd.laddr, Err: err}
+	}
+	return nil
+}
+
+// SetReadBuffer sets the size of the operating system's
+// receive buffer associated with the connection.
+func (c *conn) SetReadBuffer(bytes int) error {
+	if !c.ok() {
+		return syscall.EINVAL
+	}
+	if err := setReadBuffer(c.fd, bytes); err != nil {
+		return &OpError{Op: "set", Net: c.fd.net, Source: nil, Addr: c.fd.laddr, Err: err}
+	}
+	return nil
+}
+
+// SetWriteBuffer sets the size of the operating system's
+// transmit buffer associated with the connection.
+func (c *conn) SetWriteBuffer(bytes int) error {
+	if !c.ok() {
+		return syscall.EINVAL
+	}
+	if err := setWriteBuffer(c.fd, bytes); err != nil {
+		return &OpError{Op: "set", Net: c.fd.net, Source: nil, Addr: c.fd.laddr, Err: err}
+	}
+	return nil
+}
+
+// File returns a copy of the underlying os.File.
+// It is the caller's responsibility to close f when finished.
+// Closing c does not affect f, and closing f does not affect c.
+//
+// The returned os.File's file descriptor is different from the connection's.
+// Attempting to change properties of the original using this duplicate
+// may or may not have the desired effect.
+func (c *conn) File() (f *os.File, err error) {
+	f, err = c.fd.dup()
+	if err != nil {
+		err = &OpError{Op: "file", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+	}
+	return
+}
+
+// PacketConn is a generic packet-oriented network connection.
+//
+// Multiple goroutines may invoke methods on a PacketConn simultaneously.
+type PacketConn interface {
+	// ReadFrom reads a packet from the connection,
+	// copying the payload into p. It returns the number of
+	// bytes copied into p and the return address that
+	// was on the packet.
+	// It returns the number of bytes read (0 <= n <= len(p))
+	// and any error encountered. Callers should always process
+	// the n > 0 bytes returned before considering the error err.
+	// ReadFrom can be made to time out and return an error after a
+	// fixed time limit; see SetDeadline and SetReadDeadline.
+	ReadFrom(p []byte) (n int, addr Addr, err error)
+
+	// WriteTo writes a packet with payload p to addr.
+	// WriteTo can be made to time out and return an Error after a
+	// fixed time limit; see SetDeadline and SetWriteDeadline.
+	// On packet-oriented connections, write timeouts are rare.
+	WriteTo(p []byte, addr Addr) (n int, err error)
+
+	// Close closes the connection.
+	// Any blocked ReadFrom or WriteTo operations will be unblocked and return errors.
+	Close() error
+
+	// LocalAddr returns the local network address, if known.
+	LocalAddr() Addr
+
+	// SetDeadline sets the read and write deadlines associated
+	// with the connection. It is equivalent to calling both
+	// SetReadDeadline and SetWriteDeadline.
+	//
+	// A deadline is an absolute time after which I/O operations
+	// fail instead of blocking. The deadline applies to all future
+	// and pending I/O, not just the immediately following call to
+	// Read or Write. After a deadline has been exceeded, the
+	// connection can be refreshed by setting a deadline in the future.
+	//
+	// If the deadline is exceeded a call to Read or Write or to other
+	// I/O methods will return an error that wraps os.ErrDeadlineExceeded.
+	// This can be tested using errors.Is(err, os.ErrDeadlineExceeded).
+	// The error's Timeout method will return true, but note that there
+	// are other possible errors for which the Timeout method will
+	// return true even if the deadline has not been exceeded.
+	//
+	// An idle timeout can be implemented by repeatedly extending
+	// the deadline after successful ReadFrom or WriteTo calls.
+	//
+	// A zero value for t means I/O operations will not time out.
+	SetDeadline(t time.Time) error
+
+	// SetReadDeadline sets the deadline for future ReadFrom calls
+	// and any currently-blocked ReadFrom call.
+	// A zero value for t means ReadFrom will not time out.
+	SetReadDeadline(t time.Time) error
+
+	// SetWriteDeadline sets the deadline for future WriteTo calls
+	// and any currently-blocked WriteTo call.
+	// Even if write times out, it may return n > 0, indicating that
+	// some of the data was successfully written.
+	// A zero value for t means WriteTo will not time out.
+	SetWriteDeadline(t time.Time) error
+}
+
+var listenerBacklogCache struct {
+	sync.Once
+	val int
+}
+
+// listenerBacklog is a caching wrapper around maxListenerBacklog.
+func listenerBacklog() int {
+	listenerBacklogCache.Do(func() { listenerBacklogCache.val = maxListenerBacklog() })
+	return listenerBacklogCache.val
+}
+
+// A Listener is a generic network listener for stream-oriented protocols.
+//
+// Multiple goroutines may invoke methods on a Listener simultaneously.
+type Listener interface {
+	// Accept waits for and returns the next connection to the listener.
+	Accept() (Conn, error)
+
+	// Close closes the listener.
+	// Any blocked Accept operations will be unblocked and return errors.
+	Close() error
+
+	// Addr returns the listener's network address.
+	Addr() Addr
+}
+
+// An Error represents a network error.
+type Error interface {
+	error
+	Timeout() bool // Is the error a timeout?
+
+	// Deprecated: Temporary errors are not well-defined.
+	// Most "temporary" errors are timeouts, and the few exceptions are surprising.
+	// Do not use this method.
+	Temporary() bool
+}
+
+// Various errors contained in OpError.
+var (
+	// For connection setup operations.
+	errNoSuitableAddress = errors.New("no suitable address found")
+
+	// For connection setup and write operations.
+	errMissingAddress = errors.New("missing address")
+
+	// For both read and write operations.
+	errCanceled         = canceledError{}
+	ErrWriteToConnected = errors.New("use of WriteTo with pre-connected connection")
+)
+
+// canceledError lets us return the same error string we have always
+// returned, while still being Is context.Canceled.
+type canceledError struct{}
+
+func (canceledError) Error() string { return "operation was canceled" }
+
+func (canceledError) Is(err error) bool { return err == context.Canceled }
+
+// mapErr maps from the context errors to the historical internal net
+// error values.
+func mapErr(err error) error {
+	switch err {
+	case context.Canceled:
+		return errCanceled
+	case context.DeadlineExceeded:
+		return errTimeout
+	default:
+		return err
+	}
+}
+
+// OpError is the error type usually returned by functions in the net
+// package. It describes the operation, network type, and address of
+// an error.
+type OpError struct {
+	// Op is the operation which caused the error, such as
+	// "read" or "write".
+	Op string
+
+	// Net is the network type on which this error occurred,
+	// such as "tcp" or "udp6".
+	Net string
+
+	// For operations involving a remote network connection, like
+	// Dial, Read, or Write, Source is the corresponding local
+	// network address.
+	Source Addr
+
+	// Addr is the network address for which this error occurred.
+	// For local operations, like Listen or SetDeadline, Addr is
+	// the address of the local endpoint being manipulated.
+	// For operations involving a remote network connection, like
+	// Dial, Read, or Write, Addr is the remote address of that
+	// connection.
+	Addr Addr
+
+	// Err is the error that occurred during the operation.
+	// The Error method panics if the error is nil.
+	Err error
+}
+
+func (e *OpError) Unwrap() error { return e.Err }
+
+func (e *OpError) Error() string {
+	if e == nil {
+		return "<nil>"
+	}
+	s := e.Op
+	if e.Net != "" {
+		s += " " + e.Net
+	}
+	if e.Source != nil {
+		s += " " + e.Source.String()
+	}
+	if e.Addr != nil {
+		if e.Source != nil {
+			s += "->"
+		} else {
+			s += " "
+		}
+		s += e.Addr.String()
+	}
+	s += ": " + e.Err.Error()
+	return s
+}
+
+var (
+	// aLongTimeAgo is a non-zero time, far in the past, used for
+	// immediate cancellation of dials.
+	aLongTimeAgo = time.Unix(1, 0)
+
+	// nonDeadline and noCancel are just zero values for
+	// readability with functions taking too many parameters.
+	noDeadline = time.Time{}
+	noCancel   = (chan struct{})(nil)
+)
+
+type timeout interface {
+	Timeout() bool
+}
+
+func (e *OpError) Timeout() bool {
+	if ne, ok := e.Err.(*os.SyscallError); ok {
+		t, ok := ne.Err.(timeout)
+		return ok && t.Timeout()
+	}
+	t, ok := e.Err.(timeout)
+	return ok && t.Timeout()
+}
+
+type temporary interface {
+	Temporary() bool
+}
+
+func (e *OpError) Temporary() bool {
+	// Treat ECONNRESET and ECONNABORTED as temporary errors when
+	// they come from calling accept. See issue 6163.
+	if e.Op == "accept" && isConnError(e.Err) {
+		return true
+	}
+
+	if ne, ok := e.Err.(*os.SyscallError); ok {
+		t, ok := ne.Err.(temporary)
+		return ok && t.Temporary()
+	}
+	t, ok := e.Err.(temporary)
+	return ok && t.Temporary()
+}
+
+// A ParseError is the error type of literal network address parsers.
+type ParseError struct {
+	// Type is the type of string that was expected, such as
+	// "IP address", "CIDR address".
+	Type string
+
+	// Text is the malformed text string.
+	Text string
+}
+
+func (e *ParseError) Error() string { return "invalid " + e.Type + ": " + e.Text }
+
+func (e *ParseError) Timeout() bool   { return false }
+func (e *ParseError) Temporary() bool { return false }
+
+type AddrError struct {
+	Err  string
+	Addr string
+}
+
+func (e *AddrError) Error() string {
+	if e == nil {
+		return "<nil>"
+	}
+	s := e.Err
+	if e.Addr != "" {
+		s = "address " + e.Addr + ": " + s
+	}
+	return s
+}
+
+func (e *AddrError) Timeout() bool   { return false }
+func (e *AddrError) Temporary() bool { return false }
+
+type UnknownNetworkError string
+
+func (e UnknownNetworkError) Error() string   { return "unknown network " + string(e) }
+func (e UnknownNetworkError) Timeout() bool   { return false }
+func (e UnknownNetworkError) Temporary() bool { return false }
+
+type InvalidAddrError string
+
+func (e InvalidAddrError) Error() string   { return string(e) }
+func (e InvalidAddrError) Timeout() bool   { return false }
+func (e InvalidAddrError) Temporary() bool { return false }
+
+// errTimeout exists to return the historical "i/o timeout" string
+// for context.DeadlineExceeded. See mapErr.
+// It is also used when Dialer.Deadline is exceeded.
+// error.Is(errTimeout, context.DeadlineExceeded) returns true.
+//
+// TODO(iant): We could consider changing this to os.ErrDeadlineExceeded
+// in the future, if we make
+//
+//	errors.Is(os.ErrDeadlineExceeded, context.DeadlineExceeded)
+//
+// return true.
+var errTimeout error = &timeoutError{}
+
+type timeoutError struct{}
+
+func (e *timeoutError) Error() string   { return "i/o timeout" }
+func (e *timeoutError) Timeout() bool   { return true }
+func (e *timeoutError) Temporary() bool { return true }
+
+func (e *timeoutError) Is(err error) bool {
+	return err == context.DeadlineExceeded
+}
+
+// DNSConfigError represents an error reading the machine's DNS configuration.
+// (No longer used; kept for compatibility.)
+type DNSConfigError struct {
+	Err error
+}
+
+func (e *DNSConfigError) Unwrap() error   { return e.Err }
+func (e *DNSConfigError) Error() string   { return "error reading DNS config: " + e.Err.Error() }
+func (e *DNSConfigError) Timeout() bool   { return false }
+func (e *DNSConfigError) Temporary() bool { return false }
+
+// Various errors contained in DNSError.
+var (
+	errNoSuchHost = errors.New("no such host")
+)
+
+// DNSError represents a DNS lookup error.
+type DNSError struct {
+	Err         string // description of the error
+	Name        string // name looked for
+	Server      string // server used
+	IsTimeout   bool   // if true, timed out; not all timeouts set this
+	IsTemporary bool   // if true, error is temporary; not all errors set this
+	IsNotFound  bool   // if true, host could not be found
+}
+
+func (e *DNSError) Error() string {
+	if e == nil {
+		return "<nil>"
+	}
+	s := "lookup " + e.Name
+	if e.Server != "" {
+		s += " on " + e.Server
+	}
+	s += ": " + e.Err
+	return s
+}
+
+// Timeout reports whether the DNS lookup is known to have timed out.
+// This is not always known; a DNS lookup may fail due to a timeout
+// and return a DNSError for which Timeout returns false.
+func (e *DNSError) Timeout() bool { return e.IsTimeout }
+
+// Temporary reports whether the DNS error is known to be temporary.
+// This is not always known; a DNS lookup may fail due to a temporary
+// error and return a DNSError for which Temporary returns false.
+func (e *DNSError) Temporary() bool { return e.IsTimeout || e.IsTemporary }
+
+// errClosed exists just so that the docs for ErrClosed don't mention
+// the internal package poll.
+var errClosed = poll.ErrNetClosing
+
+// ErrClosed is the error returned by an I/O call on a network
+// connection that has already been closed, or that is closed by
+// another goroutine before the I/O is completed. This may be wrapped
+// in another error, and should normally be tested using
+// errors.Is(err, net.ErrClosed).
+var ErrClosed error = errClosed
+
+type writerOnly struct {
+	io.Writer
+}
+
+// Fallback implementation of io.ReaderFrom's ReadFrom, when sendfile isn't
+// applicable.
+func genericReadFrom(w io.Writer, r io.Reader) (n int64, err error) {
+	// Use wrapper to hide existing r.ReadFrom from io.Copy.
+	return io.Copy(writerOnly{w}, r)
+}
+
+// Limit the number of concurrent cgo-using goroutines, because
+// each will block an entire operating system thread. The usual culprit
+// is resolving many DNS names in separate goroutines but the DNS
+// server is not responding. Then the many lookups each use a different
+// thread, and the system or the program runs out of threads.
+
+var threadLimit chan struct{}
+
+var threadOnce sync.Once
+
+func acquireThread() {
+	threadOnce.Do(func() {
+		threadLimit = make(chan struct{}, concurrentThreadsLimit())
+	})
+	threadLimit <- struct{}{}
+}
+
+func releaseThread() {
+	<-threadLimit
+}
+
+// buffersWriter is the interface implemented by Conns that support a
+// "writev"-like batch write optimization.
+// writeBuffers should fully consume and write all chunks from the
+// provided Buffers, else it should report a non-nil error.
+type buffersWriter interface {
+	writeBuffers(*Buffers) (int64, error)
+}
+
+// Buffers contains zero or more runs of bytes to write.
+//
+// On certain machines, for certain types of connections, this is
+// optimized into an OS-specific batch write operation (such as
+// "writev").
+type Buffers [][]byte
+
+var (
+	_ io.WriterTo = (*Buffers)(nil)
+	_ io.Reader   = (*Buffers)(nil)
+)
+
+// WriteTo writes contents of the buffers to w.
+//
+// WriteTo implements io.WriterTo for Buffers.
+//
+// WriteTo modifies the slice v as well as v[i] for 0 <= i < len(v),
+// but does not modify v[i][j] for any i, j.
+func (v *Buffers) WriteTo(w io.Writer) (n int64, err error) {
+	if wv, ok := w.(buffersWriter); ok {
+		return wv.writeBuffers(v)
+	}
+	for _, b := range *v {
+		nb, err := w.Write(b)
+		n += int64(nb)
+		if err != nil {
+			v.consume(n)
+			return n, err
+		}
+	}
+	v.consume(n)
+	return n, nil
+}
+
+// Read from the buffers.
+//
+// Read implements io.Reader for Buffers.
+//
+// Read modifies the slice v as well as v[i] for 0 <= i < len(v),
+// but does not modify v[i][j] for any i, j.
+func (v *Buffers) Read(p []byte) (n int, err error) {
+	for len(p) > 0 && len(*v) > 0 {
+		n0 := copy(p, (*v)[0])
+		v.consume(int64(n0))
+		p = p[n0:]
+		n += n0
+	}
+	if len(*v) == 0 {
+		err = io.EOF
+	}
+	return
+}
+
+func (v *Buffers) consume(n int64) {
+	for len(*v) > 0 {
+		ln0 := int64(len((*v)[0]))
+		if ln0 > n {
+			(*v)[0] = (*v)[0][n:]
+			return
+		}
+		n -= ln0
+		(*v)[0] = nil
+		*v = (*v)[1:]
+	}
+}
diff --git a/contrib/go/_std_1.18/src/net/netip/leaf_alts.go b/contrib/go/_std_1.19/src/net/netip/leaf_alts.go
index 70513abfd9..70513abfd9 100644
--- a/contrib/go/_std_1.18/src/net/netip/leaf_alts.go
+++ b/contrib/go/_std_1.19/src/net/netip/leaf_alts.go
diff --git a/contrib/go/_std_1.19/src/net/netip/netip.go b/contrib/go/_std_1.19/src/net/netip/netip.go
new file mode 100644
index 0000000000..bb83371a55
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/netip/netip.go
@@ -0,0 +1,1504 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package netip defines an IP address type that's a small value type.
+// Building on that Addr type, the package also defines AddrPort (an
+// IP address and a port), and Prefix (an IP address and a bit length
+// prefix).
+//
+// Compared to the net.IP type, this package's Addr type takes less
+// memory, is immutable, and is comparable (supports == and being a
+// map key).
+package netip
+
+import (
+	"errors"
+	"math"
+	"strconv"
+
+	"internal/bytealg"
+	"internal/intern"
+	"internal/itoa"
+)
+
+// Sizes: (64-bit)
+//   net.IP:     24 byte slice header + {4, 16} = 28 to 40 bytes
+//   net.IPAddr: 40 byte slice header + {4, 16} = 44 to 56 bytes + zone length
+//   netip.Addr: 24 bytes (zone is per-name singleton, shared across all users)
+
+// Addr represents an IPv4 or IPv6 address (with or without a scoped
+// addressing zone), similar to net.IP or net.IPAddr.
+//
+// Unlike net.IP or net.IPAddr, Addr is a comparable value
+// type (it supports == and can be a map key) and is immutable.
+//
+// The zero Addr is not a valid IP address.
+// Addr{} is distinct from both 0.0.0.0 and ::.
+type Addr struct {
+	// addr is the hi and lo bits of an IPv6 address. If z==z4,
+	// hi and lo contain the IPv4-mapped IPv6 address.
+	//
+	// hi and lo are constructed by interpreting a 16-byte IPv6
+	// address as a big-endian 128-bit number. The most significant
+	// bits of that number go into hi, the rest into lo.
+	//
+	// For example, 0011:2233:4455:6677:8899:aabb:ccdd:eeff is stored as:
+	//  addr.hi = 0x0011223344556677
+	//  addr.lo = 0x8899aabbccddeeff
+	//
+	// We store IPs like this, rather than as [16]byte, because it
+	// turns most operations on IPs into arithmetic and bit-twiddling
+	// operations on 64-bit registers, which is much faster than
+	// bytewise processing.
+	addr uint128
+
+	// z is a combination of the address family and the IPv6 zone.
+	//
+	// nil means invalid IP address (for a zero Addr).
+	// z4 means an IPv4 address.
+	// z6noz means an IPv6 address without a zone.
+	//
+	// Otherwise it's the interned zone name string.
+	z *intern.Value
+}
+
+// z0, z4, and z6noz are sentinel Addr.z values.
+// See the Addr type's field docs.
+var (
+	z0    = (*intern.Value)(nil)
+	z4    = new(intern.Value)
+	z6noz = new(intern.Value)
+)
+
+// IPv6LinkLocalAllNodes returns the IPv6 link-local all nodes multicast
+// address ff02::1.
+func IPv6LinkLocalAllNodes() Addr { return AddrFrom16([16]byte{0: 0xff, 1: 0x02, 15: 0x01}) }
+
+// IPv6Unspecified returns the IPv6 unspecified address "::".
+func IPv6Unspecified() Addr { return Addr{z: z6noz} }
+
+// IPv4Unspecified returns the IPv4 unspecified address "0.0.0.0".
+func IPv4Unspecified() Addr { return AddrFrom4([4]byte{}) }
+
+// AddrFrom4 returns the address of the IPv4 address given by the bytes in addr.
+func AddrFrom4(addr [4]byte) Addr {
+	return Addr{
+		addr: uint128{0, 0xffff00000000 | uint64(addr[0])<<24 | uint64(addr[1])<<16 | uint64(addr[2])<<8 | uint64(addr[3])},
+		z:    z4,
+	}
+}
+
+// AddrFrom16 returns the IPv6 address given by the bytes in addr.
+// An IPv4-mapped IPv6 address is left as an IPv6 address.
+// (Use Unmap to convert them if needed.)
+func AddrFrom16(addr [16]byte) Addr {
+	return Addr{
+		addr: uint128{
+			beUint64(addr[:8]),
+			beUint64(addr[8:]),
+		},
+		z: z6noz,
+	}
+}
+
+// ipv6Slice is like IPv6Raw, but operates on a 16-byte slice. Assumes
+// slice is 16 bytes, caller must enforce this.
+func ipv6Slice(addr []byte) Addr {
+	return Addr{
+		addr: uint128{
+			beUint64(addr[:8]),
+			beUint64(addr[8:]),
+		},
+		z: z6noz,
+	}
+}
+
+// ParseAddr parses s as an IP address, returning the result. The string
+// s can be in dotted decimal ("192.0.2.1"), IPv6 ("2001:db8::68"),
+// or IPv6 with a scoped addressing zone ("fe80::1cc0:3e8c:119f:c2e1%ens18").
+func ParseAddr(s string) (Addr, error) {
+	for i := 0; i < len(s); i++ {
+		switch s[i] {
+		case '.':
+			return parseIPv4(s)
+		case ':':
+			return parseIPv6(s)
+		case '%':
+			// Assume that this was trying to be an IPv6 address with
+			// a zone specifier, but the address is missing.
+			return Addr{}, parseAddrError{in: s, msg: "missing IPv6 address"}
+		}
+	}
+	return Addr{}, parseAddrError{in: s, msg: "unable to parse IP"}
+}
+
+// MustParseAddr calls ParseAddr(s) and panics on error.
+// It is intended for use in tests with hard-coded strings.
+func MustParseAddr(s string) Addr {
+	ip, err := ParseAddr(s)
+	if err != nil {
+		panic(err)
+	}
+	return ip
+}
+
+type parseAddrError struct {
+	in  string // the string given to ParseAddr
+	msg string // an explanation of the parse failure
+	at  string // optionally, the unparsed portion of in at which the error occurred.
+}
+
+func (err parseAddrError) Error() string {
+	q := strconv.Quote
+	if err.at != "" {
+		return "ParseAddr(" + q(err.in) + "): " + err.msg + " (at " + q(err.at) + ")"
+	}
+	return "ParseAddr(" + q(err.in) + "): " + err.msg
+}
+
+// parseIPv4 parses s as an IPv4 address (in form "192.168.0.1").
+func parseIPv4(s string) (ip Addr, err error) {
+	var fields [4]uint8
+	var val, pos int
+	var digLen int // number of digits in current octet
+	for i := 0; i < len(s); i++ {
+		if s[i] >= '0' && s[i] <= '9' {
+			if digLen == 1 && val == 0 {
+				return Addr{}, parseAddrError{in: s, msg: "IPv4 field has octet with leading zero"}
+			}
+			val = val*10 + int(s[i]) - '0'
+			digLen++
+			if val > 255 {
+				return Addr{}, parseAddrError{in: s, msg: "IPv4 field has value >255"}
+			}
+		} else if s[i] == '.' {
+			// .1.2.3
+			// 1.2.3.
+			// 1..2.3
+			if i == 0 || i == len(s)-1 || s[i-1] == '.' {
+				return Addr{}, parseAddrError{in: s, msg: "IPv4 field must have at least one digit", at: s[i:]}
+			}
+			// 1.2.3.4.5
+			if pos == 3 {
+				return Addr{}, parseAddrError{in: s, msg: "IPv4 address too long"}
+			}
+			fields[pos] = uint8(val)
+			pos++
+			val = 0
+			digLen = 0
+		} else {
+			return Addr{}, parseAddrError{in: s, msg: "unexpected character", at: s[i:]}
+		}
+	}
+	if pos < 3 {
+		return Addr{}, parseAddrError{in: s, msg: "IPv4 address too short"}
+	}
+	fields[3] = uint8(val)
+	return AddrFrom4(fields), nil
+}
+
+// parseIPv6 parses s as an IPv6 address (in form "2001:db8::68").
+func parseIPv6(in string) (Addr, error) {
+	s := in
+
+	// Split off the zone right from the start. Yes it's a second scan
+	// of the string, but trying to handle it inline makes a bunch of
+	// other inner loop conditionals more expensive, and it ends up
+	// being slower.
+	zone := ""
+	i := bytealg.IndexByteString(s, '%')
+	if i != -1 {
+		s, zone = s[:i], s[i+1:]
+		if zone == "" {
+			// Not allowed to have an empty zone if explicitly specified.
+			return Addr{}, parseAddrError{in: in, msg: "zone must be a non-empty string"}
+		}
+	}
+
+	var ip [16]byte
+	ellipsis := -1 // position of ellipsis in ip
+
+	// Might have leading ellipsis
+	if len(s) >= 2 && s[0] == ':' && s[1] == ':' {
+		ellipsis = 0
+		s = s[2:]
+		// Might be only ellipsis
+		if len(s) == 0 {
+			return IPv6Unspecified().WithZone(zone), nil
+		}
+	}
+
+	// Loop, parsing hex numbers followed by colon.
+	i = 0
+	for i < 16 {
+		// Hex number. Similar to parseIPv4, inlining the hex number
+		// parsing yields a significant performance increase.
+		off := 0
+		acc := uint32(0)
+		for ; off < len(s); off++ {
+			c := s[off]
+			if c >= '0' && c <= '9' {
+				acc = (acc << 4) + uint32(c-'0')
+			} else if c >= 'a' && c <= 'f' {
+				acc = (acc << 4) + uint32(c-'a'+10)
+			} else if c >= 'A' && c <= 'F' {
+				acc = (acc << 4) + uint32(c-'A'+10)
+			} else {
+				break
+			}
+			if acc > math.MaxUint16 {
+				// Overflow, fail.
+				return Addr{}, parseAddrError{in: in, msg: "IPv6 field has value >=2^16", at: s}
+			}
+		}
+		if off == 0 {
+			// No digits found, fail.
+			return Addr{}, parseAddrError{in: in, msg: "each colon-separated field must have at least one digit", at: s}
+		}
+
+		// If followed by dot, might be in trailing IPv4.
+		if off < len(s) && s[off] == '.' {
+			if ellipsis < 0 && i != 12 {
+				// Not the right place.
+				return Addr{}, parseAddrError{in: in, msg: "embedded IPv4 address must replace the final 2 fields of the address", at: s}
+			}
+			if i+4 > 16 {
+				// Not enough room.
+				return Addr{}, parseAddrError{in: in, msg: "too many hex fields to fit an embedded IPv4 at the end of the address", at: s}
+			}
+			// TODO: could make this a bit faster by having a helper
+			// that parses to a [4]byte, and have both parseIPv4 and
+			// parseIPv6 use it.
+			ip4, err := parseIPv4(s)
+			if err != nil {
+				return Addr{}, parseAddrError{in: in, msg: err.Error(), at: s}
+			}
+			ip[i] = ip4.v4(0)
+			ip[i+1] = ip4.v4(1)
+			ip[i+2] = ip4.v4(2)
+			ip[i+3] = ip4.v4(3)
+			s = ""
+			i += 4
+			break
+		}
+
+		// Save this 16-bit chunk.
+		ip[i] = byte(acc >> 8)
+		ip[i+1] = byte(acc)
+		i += 2
+
+		// Stop at end of string.
+		s = s[off:]
+		if len(s) == 0 {
+			break
+		}
+
+		// Otherwise must be followed by colon and more.
+		if s[0] != ':' {
+			return Addr{}, parseAddrError{in: in, msg: "unexpected character, want colon", at: s}
+		} else if len(s) == 1 {
+			return Addr{}, parseAddrError{in: in, msg: "colon must be followed by more characters", at: s}
+		}
+		s = s[1:]
+
+		// Look for ellipsis.
+		if s[0] == ':' {
+			if ellipsis >= 0 { // already have one
+				return Addr{}, parseAddrError{in: in, msg: "multiple :: in address", at: s}
+			}
+			ellipsis = i
+			s = s[1:]
+			if len(s) == 0 { // can be at end
+				break
+			}
+		}
+	}
+
+	// Must have used entire string.
+	if len(s) != 0 {
+		return Addr{}, parseAddrError{in: in, msg: "trailing garbage after address", at: s}
+	}
+
+	// If didn't parse enough, expand ellipsis.
+	if i < 16 {
+		if ellipsis < 0 {
+			return Addr{}, parseAddrError{in: in, msg: "address string too short"}
+		}
+		n := 16 - i
+		for j := i - 1; j >= ellipsis; j-- {
+			ip[j+n] = ip[j]
+		}
+		for j := ellipsis + n - 1; j >= ellipsis; j-- {
+			ip[j] = 0
+		}
+	} else if ellipsis >= 0 {
+		// Ellipsis must represent at least one 0 group.
+		return Addr{}, parseAddrError{in: in, msg: "the :: must expand to at least one field of zeros"}
+	}
+	return AddrFrom16(ip).WithZone(zone), nil
+}
+
+// AddrFromSlice parses the 4- or 16-byte byte slice as an IPv4 or IPv6 address.
+// Note that a net.IP can be passed directly as the []byte argument.
+// If slice's length is not 4 or 16, AddrFromSlice returns Addr{}, false.
+func AddrFromSlice(slice []byte) (ip Addr, ok bool) {
+	switch len(slice) {
+	case 4:
+		return AddrFrom4(*(*[4]byte)(slice)), true
+	case 16:
+		return ipv6Slice(slice), true
+	}
+	return Addr{}, false
+}
+
+// v4 returns the i'th byte of ip. If ip is not an IPv4, v4 returns
+// unspecified garbage.
+func (ip Addr) v4(i uint8) uint8 {
+	return uint8(ip.addr.lo >> ((3 - i) * 8))
+}
+
+// v6 returns the i'th byte of ip. If ip is an IPv4 address, this
+// accesses the IPv4-mapped IPv6 address form of the IP.
+func (ip Addr) v6(i uint8) uint8 {
+	return uint8(*(ip.addr.halves()[(i/8)%2]) >> ((7 - i%8) * 8))
+}
+
+// v6u16 returns the i'th 16-bit word of ip. If ip is an IPv4 address,
+// this accesses the IPv4-mapped IPv6 address form of the IP.
+func (ip Addr) v6u16(i uint8) uint16 {
+	return uint16(*(ip.addr.halves()[(i/4)%2]) >> ((3 - i%4) * 16))
+}
+
+// isZero reports whether ip is the zero value of the IP type.
+// The zero value is not a valid IP address of any type.
+//
+// Note that "0.0.0.0" and "::" are not the zero value. Use IsUnspecified to
+// check for these values instead.
+func (ip Addr) isZero() bool {
+	// Faster than comparing ip == Addr{}, but effectively equivalent,
+	// as there's no way to make an IP with a nil z from this package.
+	return ip.z == z0
+}
+
+// IsValid reports whether the Addr is an initialized address (not the zero Addr).
+//
+// Note that "0.0.0.0" and "::" are both valid values.
+func (ip Addr) IsValid() bool { return ip.z != z0 }
+
+// BitLen returns the number of bits in the IP address:
+// 128 for IPv6, 32 for IPv4, and 0 for the zero Addr.
+//
+// Note that IPv4-mapped IPv6 addresses are considered IPv6 addresses
+// and therefore have bit length 128.
+func (ip Addr) BitLen() int {
+	switch ip.z {
+	case z0:
+		return 0
+	case z4:
+		return 32
+	}
+	return 128
+}
+
+// Zone returns ip's IPv6 scoped addressing zone, if any.
+func (ip Addr) Zone() string {
+	if ip.z == nil {
+		return ""
+	}
+	zone, _ := ip.z.Get().(string)
+	return zone
+}
+
+// Compare returns an integer comparing two IPs.
+// The result will be 0 if ip == ip2, -1 if ip < ip2, and +1 if ip > ip2.
+// The definition of "less than" is the same as the Less method.
+func (ip Addr) Compare(ip2 Addr) int {
+	f1, f2 := ip.BitLen(), ip2.BitLen()
+	if f1 < f2 {
+		return -1
+	}
+	if f1 > f2 {
+		return 1
+	}
+	hi1, hi2 := ip.addr.hi, ip2.addr.hi
+	if hi1 < hi2 {
+		return -1
+	}
+	if hi1 > hi2 {
+		return 1
+	}
+	lo1, lo2 := ip.addr.lo, ip2.addr.lo
+	if lo1 < lo2 {
+		return -1
+	}
+	if lo1 > lo2 {
+		return 1
+	}
+	if ip.Is6() {
+		za, zb := ip.Zone(), ip2.Zone()
+		if za < zb {
+			return -1
+		}
+		if za > zb {
+			return 1
+		}
+	}
+	return 0
+}
+
+// Less reports whether ip sorts before ip2.
+// IP addresses sort first by length, then their address.
+// IPv6 addresses with zones sort just after the same address without a zone.
+func (ip Addr) Less(ip2 Addr) bool { return ip.Compare(ip2) == -1 }
+
+func (ip Addr) lessOrEq(ip2 Addr) bool { return ip.Compare(ip2) <= 0 }
+
+// Is4 reports whether ip is an IPv4 address.
+//
+// It returns false for IPv4-mapped IPv6 addresses. See Addr.Unmap.
+func (ip Addr) Is4() bool {
+	return ip.z == z4
+}
+
+// Is4In6 reports whether ip is an IPv4-mapped IPv6 address.
+func (ip Addr) Is4In6() bool {
+	return ip.Is6() && ip.addr.hi == 0 && ip.addr.lo>>32 == 0xffff
+}
+
+// Is6 reports whether ip is an IPv6 address, including IPv4-mapped
+// IPv6 addresses.
+func (ip Addr) Is6() bool {
+	return ip.z != z0 && ip.z != z4
+}
+
+// Unmap returns ip with any IPv4-mapped IPv6 address prefix removed.
+//
+// That is, if ip is an IPv6 address wrapping an IPv4 address, it
+// returns the wrapped IPv4 address. Otherwise it returns ip unmodified.
+func (ip Addr) Unmap() Addr {
+	if ip.Is4In6() {
+		ip.z = z4
+	}
+	return ip
+}
+
+// WithZone returns an IP that's the same as ip but with the provided
+// zone. If zone is empty, the zone is removed. If ip is an IPv4
+// address, WithZone is a no-op and returns ip unchanged.
+func (ip Addr) WithZone(zone string) Addr {
+	if !ip.Is6() {
+		return ip
+	}
+	if zone == "" {
+		ip.z = z6noz
+		return ip
+	}
+	ip.z = intern.GetByString(zone)
+	return ip
+}
+
+// withoutZone unconditionally strips the zone from ip.
+// It's similar to WithZone, but small enough to be inlinable.
+func (ip Addr) withoutZone() Addr {
+	if !ip.Is6() {
+		return ip
+	}
+	ip.z = z6noz
+	return ip
+}
+
+// hasZone reports whether ip has an IPv6 zone.
+func (ip Addr) hasZone() bool {
+	return ip.z != z0 && ip.z != z4 && ip.z != z6noz
+}
+
+// IsLinkLocalUnicast reports whether ip is a link-local unicast address.
+func (ip Addr) IsLinkLocalUnicast() bool {
+	// Dynamic Configuration of IPv4 Link-Local Addresses
+	// https://datatracker.ietf.org/doc/html/rfc3927#section-2.1
+	if ip.Is4() {
+		return ip.v4(0) == 169 && ip.v4(1) == 254
+	}
+	// IP Version 6 Addressing Architecture (2.4 Address Type Identification)
+	// https://datatracker.ietf.org/doc/html/rfc4291#section-2.4
+	if ip.Is6() {
+		return ip.v6u16(0)&0xffc0 == 0xfe80
+	}
+	return false // zero value
+}
+
+// IsLoopback reports whether ip is a loopback address.
+func (ip Addr) IsLoopback() bool {
+	// Requirements for Internet Hosts -- Communication Layers (3.2.1.3 Addressing)
+	// https://datatracker.ietf.org/doc/html/rfc1122#section-3.2.1.3
+	if ip.Is4() {
+		return ip.v4(0) == 127
+	}
+	// IP Version 6 Addressing Architecture (2.4 Address Type Identification)
+	// https://datatracker.ietf.org/doc/html/rfc4291#section-2.4
+	if ip.Is6() {
+		return ip.addr.hi == 0 && ip.addr.lo == 1
+	}
+	return false // zero value
+}
+
+// IsMulticast reports whether ip is a multicast address.
+func (ip Addr) IsMulticast() bool {
+	// Host Extensions for IP Multicasting (4. HOST GROUP ADDRESSES)
+	// https://datatracker.ietf.org/doc/html/rfc1112#section-4
+	if ip.Is4() {
+		return ip.v4(0)&0xf0 == 0xe0
+	}
+	// IP Version 6 Addressing Architecture (2.4 Address Type Identification)
+	// https://datatracker.ietf.org/doc/html/rfc4291#section-2.4
+	if ip.Is6() {
+		return ip.addr.hi>>(64-8) == 0xff // ip.v6(0) == 0xff
+	}
+	return false // zero value
+}
+
+// IsInterfaceLocalMulticast reports whether ip is an IPv6 interface-local
+// multicast address.
+func (ip Addr) IsInterfaceLocalMulticast() bool {
+	// IPv6 Addressing Architecture (2.7.1. Pre-Defined Multicast Addresses)
+	// https://datatracker.ietf.org/doc/html/rfc4291#section-2.7.1
+	if ip.Is6() {
+		return ip.v6u16(0)&0xff0f == 0xff01
+	}
+	return false // zero value
+}
+
+// IsLinkLocalMulticast reports whether ip is a link-local multicast address.
+func (ip Addr) IsLinkLocalMulticast() bool {
+	// IPv4 Multicast Guidelines (4. Local Network Control Block (224.0.0/24))
+	// https://datatracker.ietf.org/doc/html/rfc5771#section-4
+	if ip.Is4() {
+		return ip.v4(0) == 224 && ip.v4(1) == 0 && ip.v4(2) == 0
+	}
+	// IPv6 Addressing Architecture (2.7.1. Pre-Defined Multicast Addresses)
+	// https://datatracker.ietf.org/doc/html/rfc4291#section-2.7.1
+	if ip.Is6() {
+		return ip.v6u16(0)&0xff0f == 0xff02
+	}
+	return false // zero value
+}
+
+// IsGlobalUnicast reports whether ip is a global unicast address.
+//
+// It returns true for IPv6 addresses which fall outside of the current
+// IANA-allocated 2000::/3 global unicast space, with the exception of the
+// link-local address space. It also returns true even if ip is in the IPv4
+// private address space or IPv6 unique local address space.
+// It returns false for the zero Addr.
+//
+// For reference, see RFC 1122, RFC 4291, and RFC 4632.
+func (ip Addr) IsGlobalUnicast() bool {
+	if ip.z == z0 {
+		// Invalid or zero-value.
+		return false
+	}
+
+	// Match package net's IsGlobalUnicast logic. Notably private IPv4 addresses
+	// and ULA IPv6 addresses are still considered "global unicast".
+	if ip.Is4() && (ip == IPv4Unspecified() || ip == AddrFrom4([4]byte{255, 255, 255, 255})) {
+		return false
+	}
+
+	return ip != IPv6Unspecified() &&
+		!ip.IsLoopback() &&
+		!ip.IsMulticast() &&
+		!ip.IsLinkLocalUnicast()
+}
+
+// IsPrivate reports whether ip is a private address, according to RFC 1918
+// (IPv4 addresses) and RFC 4193 (IPv6 addresses). That is, it reports whether
+// ip is in 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16, or fc00::/7. This is the
+// same as net.IP.IsPrivate.
+func (ip Addr) IsPrivate() bool {
+	// Match the stdlib's IsPrivate logic.
+	if ip.Is4() {
+		// RFC 1918 allocates 10.0.0.0/8, 172.16.0.0/12, and 192.168.0.0/16 as
+		// private IPv4 address subnets.
+		return ip.v4(0) == 10 ||
+			(ip.v4(0) == 172 && ip.v4(1)&0xf0 == 16) ||
+			(ip.v4(0) == 192 && ip.v4(1) == 168)
+	}
+
+	if ip.Is6() {
+		// RFC 4193 allocates fc00::/7 as the unique local unicast IPv6 address
+		// subnet.
+		return ip.v6(0)&0xfe == 0xfc
+	}
+
+	return false // zero value
+}
+
+// IsUnspecified reports whether ip is an unspecified address, either the IPv4
+// address "0.0.0.0" or the IPv6 address "::".
+//
+// Note that the zero Addr is not an unspecified address.
+func (ip Addr) IsUnspecified() bool {
+	return ip == IPv4Unspecified() || ip == IPv6Unspecified()
+}
+
+// Prefix keeps only the top b bits of IP, producing a Prefix
+// of the specified length.
+// If ip is a zero Addr, Prefix always returns a zero Prefix and a nil error.
+// Otherwise, if bits is less than zero or greater than ip.BitLen(),
+// Prefix returns an error.
+func (ip Addr) Prefix(b int) (Prefix, error) {
+	if b < 0 {
+		return Prefix{}, errors.New("negative Prefix bits")
+	}
+	effectiveBits := b
+	switch ip.z {
+	case z0:
+		return Prefix{}, nil
+	case z4:
+		if b > 32 {
+			return Prefix{}, errors.New("prefix length " + itoa.Itoa(b) + " too large for IPv4")
+		}
+		effectiveBits += 96
+	default:
+		if b > 128 {
+			return Prefix{}, errors.New("prefix length " + itoa.Itoa(b) + " too large for IPv6")
+		}
+	}
+	ip.addr = ip.addr.and(mask6(effectiveBits))
+	return PrefixFrom(ip, b), nil
+}
+
+const (
+	netIPv4len = 4
+	netIPv6len = 16
+)
+
+// As16 returns the IP address in its 16-byte representation.
+// IPv4 addresses are returned as IPv4-mapped IPv6 addresses.
+// IPv6 addresses with zones are returned without their zone (use the
+// Zone method to get it).
+// The ip zero value returns all zeroes.
+func (ip Addr) As16() (a16 [16]byte) {
+	bePutUint64(a16[:8], ip.addr.hi)
+	bePutUint64(a16[8:], ip.addr.lo)
+	return a16
+}
+
+// As4 returns an IPv4 or IPv4-in-IPv6 address in its 4-byte representation.
+// If ip is the zero Addr or an IPv6 address, As4 panics.
+// Note that 0.0.0.0 is not the zero Addr.
+func (ip Addr) As4() (a4 [4]byte) {
+	if ip.z == z4 || ip.Is4In6() {
+		bePutUint32(a4[:], uint32(ip.addr.lo))
+		return a4
+	}
+	if ip.z == z0 {
+		panic("As4 called on IP zero value")
+	}
+	panic("As4 called on IPv6 address")
+}
+
+// AsSlice returns an IPv4 or IPv6 address in its respective 4-byte or 16-byte representation.
+func (ip Addr) AsSlice() []byte {
+	switch ip.z {
+	case z0:
+		return nil
+	case z4:
+		var ret [4]byte
+		bePutUint32(ret[:], uint32(ip.addr.lo))
+		return ret[:]
+	default:
+		var ret [16]byte
+		bePutUint64(ret[:8], ip.addr.hi)
+		bePutUint64(ret[8:], ip.addr.lo)
+		return ret[:]
+	}
+}
+
+// Next returns the address following ip.
+// If there is none, it returns the zero Addr.
+func (ip Addr) Next() Addr {
+	ip.addr = ip.addr.addOne()
+	if ip.Is4() {
+		if uint32(ip.addr.lo) == 0 {
+			// Overflowed.
+			return Addr{}
+		}
+	} else {
+		if ip.addr.isZero() {
+			// Overflowed
+			return Addr{}
+		}
+	}
+	return ip
+}
+
+// Prev returns the IP before ip.
+// If there is none, it returns the IP zero value.
+func (ip Addr) Prev() Addr {
+	if ip.Is4() {
+		if uint32(ip.addr.lo) == 0 {
+			return Addr{}
+		}
+	} else if ip.addr.isZero() {
+		return Addr{}
+	}
+	ip.addr = ip.addr.subOne()
+	return ip
+}
+
+// String returns the string form of the IP address ip.
+// It returns one of 5 forms:
+//
+//   - "invalid IP", if ip is the zero Addr
+//   - IPv4 dotted decimal ("192.0.2.1")
+//   - IPv6 ("2001:db8::1")
+//   - "::ffff:1.2.3.4" (if Is4In6)
+//   - IPv6 with zone ("fe80:db8::1%eth0")
+//
+// Note that unlike package net's IP.String method,
+// IPv4-mapped IPv6 addresses format with a "::ffff:"
+// prefix before the dotted quad.
+func (ip Addr) String() string {
+	switch ip.z {
+	case z0:
+		return "invalid IP"
+	case z4:
+		return ip.string4()
+	default:
+		if ip.Is4In6() {
+			if z := ip.Zone(); z != "" {
+				return "::ffff:" + ip.Unmap().string4() + "%" + z
+			} else {
+				return "::ffff:" + ip.Unmap().string4()
+			}
+		}
+		return ip.string6()
+	}
+}
+
+// AppendTo appends a text encoding of ip,
+// as generated by MarshalText,
+// to b and returns the extended buffer.
+func (ip Addr) AppendTo(b []byte) []byte {
+	switch ip.z {
+	case z0:
+		return b
+	case z4:
+		return ip.appendTo4(b)
+	default:
+		if ip.Is4In6() {
+			b = append(b, "::ffff:"...)
+			b = ip.Unmap().appendTo4(b)
+			if z := ip.Zone(); z != "" {
+				b = append(b, '%')
+				b = append(b, z...)
+			}
+			return b
+		}
+		return ip.appendTo6(b)
+	}
+}
+
+// digits is a string of the hex digits from 0 to f. It's used in
+// appendDecimal and appendHex to format IP addresses.
+const digits = "0123456789abcdef"
+
+// appendDecimal appends the decimal string representation of x to b.
+func appendDecimal(b []byte, x uint8) []byte {
+	// Using this function rather than strconv.AppendUint makes IPv4
+	// string building 2x faster.
+
+	if x >= 100 {
+		b = append(b, digits[x/100])
+	}
+	if x >= 10 {
+		b = append(b, digits[x/10%10])
+	}
+	return append(b, digits[x%10])
+}
+
+// appendHex appends the hex string representation of x to b.
+func appendHex(b []byte, x uint16) []byte {
+	// Using this function rather than strconv.AppendUint makes IPv6
+	// string building 2x faster.
+
+	if x >= 0x1000 {
+		b = append(b, digits[x>>12])
+	}
+	if x >= 0x100 {
+		b = append(b, digits[x>>8&0xf])
+	}
+	if x >= 0x10 {
+		b = append(b, digits[x>>4&0xf])
+	}
+	return append(b, digits[x&0xf])
+}
+
+// appendHexPad appends the fully padded hex string representation of x to b.
+func appendHexPad(b []byte, x uint16) []byte {
+	return append(b, digits[x>>12], digits[x>>8&0xf], digits[x>>4&0xf], digits[x&0xf])
+}
+
+func (ip Addr) string4() string {
+	const max = len("255.255.255.255")
+	ret := make([]byte, 0, max)
+	ret = ip.appendTo4(ret)
+	return string(ret)
+}
+
+func (ip Addr) appendTo4(ret []byte) []byte {
+	ret = appendDecimal(ret, ip.v4(0))
+	ret = append(ret, '.')
+	ret = appendDecimal(ret, ip.v4(1))
+	ret = append(ret, '.')
+	ret = appendDecimal(ret, ip.v4(2))
+	ret = append(ret, '.')
+	ret = appendDecimal(ret, ip.v4(3))
+	return ret
+}
+
+// string6 formats ip in IPv6 textual representation. It follows the
+// guidelines in section 4 of RFC 5952
+// (https://tools.ietf.org/html/rfc5952#section-4): no unnecessary
+// zeros, use :: to elide the longest run of zeros, and don't use ::
+// to compact a single zero field.
+func (ip Addr) string6() string {
+	// Use a zone with a "plausibly long" name, so that most zone-ful
+	// IP addresses won't require additional allocation.
+	//
+	// The compiler does a cool optimization here, where ret ends up
+	// stack-allocated and so the only allocation this function does
+	// is to construct the returned string. As such, it's okay to be a
+	// bit greedy here, size-wise.
+	const max = len("ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff%enp5s0")
+	ret := make([]byte, 0, max)
+	ret = ip.appendTo6(ret)
+	return string(ret)
+}
+
+func (ip Addr) appendTo6(ret []byte) []byte {
+	zeroStart, zeroEnd := uint8(255), uint8(255)
+	for i := uint8(0); i < 8; i++ {
+		j := i
+		for j < 8 && ip.v6u16(j) == 0 {
+			j++
+		}
+		if l := j - i; l >= 2 && l > zeroEnd-zeroStart {
+			zeroStart, zeroEnd = i, j
+		}
+	}
+
+	for i := uint8(0); i < 8; i++ {
+		if i == zeroStart {
+			ret = append(ret, ':', ':')
+			i = zeroEnd
+			if i >= 8 {
+				break
+			}
+		} else if i > 0 {
+			ret = append(ret, ':')
+		}
+
+		ret = appendHex(ret, ip.v6u16(i))
+	}
+
+	if ip.z != z6noz {
+		ret = append(ret, '%')
+		ret = append(ret, ip.Zone()...)
+	}
+	return ret
+}
+
+// StringExpanded is like String but IPv6 addresses are expanded with leading
+// zeroes and no "::" compression. For example, "2001:db8::1" becomes
+// "2001:0db8:0000:0000:0000:0000:0000:0001".
+func (ip Addr) StringExpanded() string {
+	switch ip.z {
+	case z0, z4:
+		return ip.String()
+	}
+
+	const size = len("ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff")
+	ret := make([]byte, 0, size)
+	for i := uint8(0); i < 8; i++ {
+		if i > 0 {
+			ret = append(ret, ':')
+		}
+
+		ret = appendHexPad(ret, ip.v6u16(i))
+	}
+
+	if ip.z != z6noz {
+		// The addition of a zone will cause a second allocation, but when there
+		// is no zone the ret slice will be stack allocated.
+		ret = append(ret, '%')
+		ret = append(ret, ip.Zone()...)
+	}
+	return string(ret)
+}
+
+// MarshalText implements the encoding.TextMarshaler interface,
+// The encoding is the same as returned by String, with one exception:
+// If ip is the zero Addr, the encoding is the empty string.
+func (ip Addr) MarshalText() ([]byte, error) {
+	switch ip.z {
+	case z0:
+		return []byte(""), nil
+	case z4:
+		max := len("255.255.255.255")
+		b := make([]byte, 0, max)
+		return ip.appendTo4(b), nil
+	default:
+		max := len("ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff%enp5s0")
+		b := make([]byte, 0, max)
+		if ip.Is4In6() {
+			b = append(b, "::ffff:"...)
+			b = ip.Unmap().appendTo4(b)
+			if z := ip.Zone(); z != "" {
+				b = append(b, '%')
+				b = append(b, z...)
+			}
+			return b, nil
+		}
+		return ip.appendTo6(b), nil
+	}
+
+}
+
+// UnmarshalText implements the encoding.TextUnmarshaler interface.
+// The IP address is expected in a form accepted by ParseAddr.
+//
+// If text is empty, UnmarshalText sets *ip to the zero Addr and
+// returns no error.
+func (ip *Addr) UnmarshalText(text []byte) error {
+	if len(text) == 0 {
+		*ip = Addr{}
+		return nil
+	}
+	var err error
+	*ip, err = ParseAddr(string(text))
+	return err
+}
+
+func (ip Addr) marshalBinaryWithTrailingBytes(trailingBytes int) []byte {
+	var b []byte
+	switch ip.z {
+	case z0:
+		b = make([]byte, trailingBytes)
+	case z4:
+		b = make([]byte, 4+trailingBytes)
+		bePutUint32(b, uint32(ip.addr.lo))
+	default:
+		z := ip.Zone()
+		b = make([]byte, 16+len(z)+trailingBytes)
+		bePutUint64(b[:8], ip.addr.hi)
+		bePutUint64(b[8:], ip.addr.lo)
+		copy(b[16:], z)
+	}
+	return b
+}
+
+// MarshalBinary implements the encoding.BinaryMarshaler interface.
+// It returns a zero-length slice for the zero Addr,
+// the 4-byte form for an IPv4 address,
+// and the 16-byte form with zone appended for an IPv6 address.
+func (ip Addr) MarshalBinary() ([]byte, error) {
+	return ip.marshalBinaryWithTrailingBytes(0), nil
+}
+
+// UnmarshalBinary implements the encoding.BinaryUnmarshaler interface.
+// It expects data in the form generated by MarshalBinary.
+func (ip *Addr) UnmarshalBinary(b []byte) error {
+	n := len(b)
+	switch {
+	case n == 0:
+		*ip = Addr{}
+		return nil
+	case n == 4:
+		*ip = AddrFrom4(*(*[4]byte)(b))
+		return nil
+	case n == 16:
+		*ip = ipv6Slice(b)
+		return nil
+	case n > 16:
+		*ip = ipv6Slice(b[:16]).WithZone(string(b[16:]))
+		return nil
+	}
+	return errors.New("unexpected slice size")
+}
+
+// AddrPort is an IP and a port number.
+type AddrPort struct {
+	ip   Addr
+	port uint16
+}
+
+// AddrPortFrom returns an AddrPort with the provided IP and port.
+// It does not allocate.
+func AddrPortFrom(ip Addr, port uint16) AddrPort { return AddrPort{ip: ip, port: port} }
+
+// Addr returns p's IP address.
+func (p AddrPort) Addr() Addr { return p.ip }
+
+// Port returns p's port.
+func (p AddrPort) Port() uint16 { return p.port }
+
+// splitAddrPort splits s into an IP address string and a port
+// string. It splits strings shaped like "foo:bar" or "[foo]:bar",
+// without further validating the substrings. v6 indicates whether the
+// ip string should parse as an IPv6 address or an IPv4 address, in
+// order for s to be a valid ip:port string.
+func splitAddrPort(s string) (ip, port string, v6 bool, err error) {
+	i := stringsLastIndexByte(s, ':')
+	if i == -1 {
+		return "", "", false, errors.New("not an ip:port")
+	}
+
+	ip, port = s[:i], s[i+1:]
+	if len(ip) == 0 {
+		return "", "", false, errors.New("no IP")
+	}
+	if len(port) == 0 {
+		return "", "", false, errors.New("no port")
+	}
+	if ip[0] == '[' {
+		if len(ip) < 2 || ip[len(ip)-1] != ']' {
+			return "", "", false, errors.New("missing ]")
+		}
+		ip = ip[1 : len(ip)-1]
+		v6 = true
+	}
+
+	return ip, port, v6, nil
+}
+
+// ParseAddrPort parses s as an AddrPort.
+//
+// It doesn't do any name resolution: both the address and the port
+// must be numeric.
+func ParseAddrPort(s string) (AddrPort, error) {
+	var ipp AddrPort
+	ip, port, v6, err := splitAddrPort(s)
+	if err != nil {
+		return ipp, err
+	}
+	port16, err := strconv.ParseUint(port, 10, 16)
+	if err != nil {
+		return ipp, errors.New("invalid port " + strconv.Quote(port) + " parsing " + strconv.Quote(s))
+	}
+	ipp.port = uint16(port16)
+	ipp.ip, err = ParseAddr(ip)
+	if err != nil {
+		return AddrPort{}, err
+	}
+	if v6 && ipp.ip.Is4() {
+		return AddrPort{}, errors.New("invalid ip:port " + strconv.Quote(s) + ", square brackets can only be used with IPv6 addresses")
+	} else if !v6 && ipp.ip.Is6() {
+		return AddrPort{}, errors.New("invalid ip:port " + strconv.Quote(s) + ", IPv6 addresses must be surrounded by square brackets")
+	}
+	return ipp, nil
+}
+
+// MustParseAddrPort calls ParseAddrPort(s) and panics on error.
+// It is intended for use in tests with hard-coded strings.
+func MustParseAddrPort(s string) AddrPort {
+	ip, err := ParseAddrPort(s)
+	if err != nil {
+		panic(err)
+	}
+	return ip
+}
+
+// isZero reports whether p is the zero AddrPort.
+func (p AddrPort) isZero() bool { return p == AddrPort{} }
+
+// IsValid reports whether p.IP() is valid.
+// All ports are valid, including zero.
+func (p AddrPort) IsValid() bool { return p.ip.IsValid() }
+
+func (p AddrPort) String() string {
+	switch p.ip.z {
+	case z0:
+		return "invalid AddrPort"
+	case z4:
+		a := p.ip.As4()
+		buf := make([]byte, 0, 21)
+		for i := range a {
+			buf = strconv.AppendUint(buf, uint64(a[i]), 10)
+			buf = append(buf, "...:"[i])
+		}
+		buf = strconv.AppendUint(buf, uint64(p.port), 10)
+		return string(buf)
+	default:
+		// TODO: this could be more efficient allocation-wise:
+		return joinHostPort(p.ip.String(), itoa.Itoa(int(p.port)))
+	}
+}
+
+func joinHostPort(host, port string) string {
+	// We assume that host is a literal IPv6 address if host has
+	// colons.
+	if bytealg.IndexByteString(host, ':') >= 0 {
+		return "[" + host + "]:" + port
+	}
+	return host + ":" + port
+}
+
+// AppendTo appends a text encoding of p,
+// as generated by MarshalText,
+// to b and returns the extended buffer.
+func (p AddrPort) AppendTo(b []byte) []byte {
+	switch p.ip.z {
+	case z0:
+		return b
+	case z4:
+		b = p.ip.appendTo4(b)
+	default:
+		if p.ip.Is4In6() {
+			b = append(b, "[::ffff:"...)
+			b = p.ip.Unmap().appendTo4(b)
+			if z := p.ip.Zone(); z != "" {
+				b = append(b, '%')
+				b = append(b, z...)
+			}
+		} else {
+			b = append(b, '[')
+			b = p.ip.appendTo6(b)
+		}
+		b = append(b, ']')
+	}
+	b = append(b, ':')
+	b = strconv.AppendUint(b, uint64(p.port), 10)
+	return b
+}
+
+// MarshalText implements the encoding.TextMarshaler interface. The
+// encoding is the same as returned by String, with one exception: if
+// p.Addr() is the zero Addr, the encoding is the empty string.
+func (p AddrPort) MarshalText() ([]byte, error) {
+	var max int
+	switch p.ip.z {
+	case z0:
+	case z4:
+		max = len("255.255.255.255:65535")
+	default:
+		max = len("[ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff%enp5s0]:65535")
+	}
+	b := make([]byte, 0, max)
+	b = p.AppendTo(b)
+	return b, nil
+}
+
+// UnmarshalText implements the encoding.TextUnmarshaler
+// interface. The AddrPort is expected in a form
+// generated by MarshalText or accepted by ParseAddrPort.
+func (p *AddrPort) UnmarshalText(text []byte) error {
+	if len(text) == 0 {
+		*p = AddrPort{}
+		return nil
+	}
+	var err error
+	*p, err = ParseAddrPort(string(text))
+	return err
+}
+
+// MarshalBinary implements the encoding.BinaryMarshaler interface.
+// It returns Addr.MarshalBinary with an additional two bytes appended
+// containing the port in little-endian.
+func (p AddrPort) MarshalBinary() ([]byte, error) {
+	b := p.Addr().marshalBinaryWithTrailingBytes(2)
+	lePutUint16(b[len(b)-2:], p.Port())
+	return b, nil
+}
+
+// UnmarshalBinary implements the encoding.BinaryUnmarshaler interface.
+// It expects data in the form generated by MarshalBinary.
+func (p *AddrPort) UnmarshalBinary(b []byte) error {
+	if len(b) < 2 {
+		return errors.New("unexpected slice size")
+	}
+	var addr Addr
+	err := addr.UnmarshalBinary(b[:len(b)-2])
+	if err != nil {
+		return err
+	}
+	*p = AddrPortFrom(addr, leUint16(b[len(b)-2:]))
+	return nil
+}
+
+// Prefix is an IP address prefix (CIDR) representing an IP network.
+//
+// The first Bits() of Addr() are specified. The remaining bits match any address.
+// The range of Bits() is [0,32] for IPv4 or [0,128] for IPv6.
+type Prefix struct {
+	ip Addr
+
+	// bits is logically a uint8 (storing [0,128]) but also
+	// encodes an "invalid" bit, currently represented by the
+	// invalidPrefixBits sentinel value. It could be packed into
+	// the uint8 more with more complicated expressions in the
+	// accessors, but the extra byte (in padding anyway) doesn't
+	// hurt and simplifies code below.
+	bits int16
+}
+
+// invalidPrefixBits is the Prefix.bits value used when PrefixFrom is
+// outside the range of a uint8. It's returned as the int -1 in the
+// public API.
+const invalidPrefixBits = -1
+
+// PrefixFrom returns a Prefix with the provided IP address and bit
+// prefix length.
+//
+// It does not allocate. Unlike Addr.Prefix, PrefixFrom does not mask
+// off the host bits of ip.
+//
+// If bits is less than zero or greater than ip.BitLen, Prefix.Bits
+// will return an invalid value -1.
+func PrefixFrom(ip Addr, bits int) Prefix {
+	if bits < 0 || bits > ip.BitLen() {
+		bits = invalidPrefixBits
+	}
+	b16 := int16(bits)
+	return Prefix{
+		ip:   ip.withoutZone(),
+		bits: b16,
+	}
+}
+
+// Addr returns p's IP address.
+func (p Prefix) Addr() Addr { return p.ip }
+
+// Bits returns p's prefix length.
+//
+// It reports -1 if invalid.
+func (p Prefix) Bits() int { return int(p.bits) }
+
+// IsValid reports whether p.Bits() has a valid range for p.IP().
+// If p.Addr() is the zero Addr, IsValid returns false.
+// Note that if p is the zero Prefix, then p.IsValid() == false.
+func (p Prefix) IsValid() bool { return !p.ip.isZero() && p.bits >= 0 && int(p.bits) <= p.ip.BitLen() }
+
+func (p Prefix) isZero() bool { return p == Prefix{} }
+
+// IsSingleIP reports whether p contains exactly one IP.
+func (p Prefix) IsSingleIP() bool { return p.bits != 0 && int(p.bits) == p.ip.BitLen() }
+
+// ParsePrefix parses s as an IP address prefix.
+// The string can be in the form "192.168.1.0/24" or "2001:db8::/32",
+// the CIDR notation defined in RFC 4632 and RFC 4291.
+// IPv6 zones are not permitted in prefixes, and an error will be returned if a
+// zone is present.
+//
+// Note that masked address bits are not zeroed. Use Masked for that.
+func ParsePrefix(s string) (Prefix, error) {
+	i := stringsLastIndexByte(s, '/')
+	if i < 0 {
+		return Prefix{}, errors.New("netip.ParsePrefix(" + strconv.Quote(s) + "): no '/'")
+	}
+	ip, err := ParseAddr(s[:i])
+	if err != nil {
+		return Prefix{}, errors.New("netip.ParsePrefix(" + strconv.Quote(s) + "): " + err.Error())
+	}
+	// IPv6 zones are not allowed: https://go.dev/issue/51899
+	if ip.Is6() && ip.z != z6noz {
+		return Prefix{}, errors.New("netip.ParsePrefix(" + strconv.Quote(s) + "): IPv6 zones cannot be present in a prefix")
+	}
+
+	bitsStr := s[i+1:]
+	bits, err := strconv.Atoi(bitsStr)
+	if err != nil {
+		return Prefix{}, errors.New("netip.ParsePrefix(" + strconv.Quote(s) + "): bad bits after slash: " + strconv.Quote(bitsStr))
+	}
+	maxBits := 32
+	if ip.Is6() {
+		maxBits = 128
+	}
+	if bits < 0 || bits > maxBits {
+		return Prefix{}, errors.New("netip.ParsePrefix(" + strconv.Quote(s) + "): prefix length out of range")
+	}
+	return PrefixFrom(ip, bits), nil
+}
+
+// MustParsePrefix calls ParsePrefix(s) and panics on error.
+// It is intended for use in tests with hard-coded strings.
+func MustParsePrefix(s string) Prefix {
+	ip, err := ParsePrefix(s)
+	if err != nil {
+		panic(err)
+	}
+	return ip
+}
+
+// Masked returns p in its canonical form, with all but the high
+// p.Bits() bits of p.Addr() masked off.
+//
+// If p is zero or otherwise invalid, Masked returns the zero Prefix.
+func (p Prefix) Masked() Prefix {
+	if m, err := p.ip.Prefix(int(p.bits)); err == nil {
+		return m
+	}
+	return Prefix{}
+}
+
+// Contains reports whether the network p includes ip.
+//
+// An IPv4 address will not match an IPv6 prefix.
+// An IPv4-mapped IPv6 address will not match an IPv4 prefix.
+// A zero-value IP will not match any prefix.
+// If ip has an IPv6 zone, Contains returns false,
+// because Prefixes strip zones.
+func (p Prefix) Contains(ip Addr) bool {
+	if !p.IsValid() || ip.hasZone() {
+		return false
+	}
+	if f1, f2 := p.ip.BitLen(), ip.BitLen(); f1 == 0 || f2 == 0 || f1 != f2 {
+		return false
+	}
+	if ip.Is4() {
+		// xor the IP addresses together; mismatched bits are now ones.
+		// Shift away the number of bits we don't care about.
+		// Shifts in Go are more efficient if the compiler can prove
+		// that the shift amount is smaller than the width of the shifted type (64 here).
+		// We know that p.bits is in the range 0..32 because p is Valid;
+		// the compiler doesn't know that, so mask with 63 to help it.
+		// Now truncate to 32 bits, because this is IPv4.
+		// If all the bits we care about are equal, the result will be zero.
+		return uint32((ip.addr.lo^p.ip.addr.lo)>>((32-p.bits)&63)) == 0
+	} else {
+		// xor the IP addresses together.
+		// Mask away the bits we don't care about.
+		// If all the bits we care about are equal, the result will be zero.
+		return ip.addr.xor(p.ip.addr).and(mask6(int(p.bits))).isZero()
+	}
+}
+
+// Overlaps reports whether p and o contain any IP addresses in common.
+//
+// If p and o are of different address families or either have a zero
+// IP, it reports false. Like the Contains method, a prefix with an
+// IPv4-mapped IPv6 address is still treated as an IPv6 mask.
+func (p Prefix) Overlaps(o Prefix) bool {
+	if !p.IsValid() || !o.IsValid() {
+		return false
+	}
+	if p == o {
+		return true
+	}
+	if p.ip.Is4() != o.ip.Is4() {
+		return false
+	}
+	var minBits int16
+	if p.bits < o.bits {
+		minBits = p.bits
+	} else {
+		minBits = o.bits
+	}
+	if minBits == 0 {
+		return true
+	}
+	// One of these Prefix calls might look redundant, but we don't require
+	// that p and o values are normalized (via Prefix.Masked) first,
+	// so the Prefix call on the one that's already minBits serves to zero
+	// out any remaining bits in IP.
+	var err error
+	if p, err = p.ip.Prefix(int(minBits)); err != nil {
+		return false
+	}
+	if o, err = o.ip.Prefix(int(minBits)); err != nil {
+		return false
+	}
+	return p.ip == o.ip
+}
+
+// AppendTo appends a text encoding of p,
+// as generated by MarshalText,
+// to b and returns the extended buffer.
+func (p Prefix) AppendTo(b []byte) []byte {
+	if p.isZero() {
+		return b
+	}
+	if !p.IsValid() {
+		return append(b, "invalid Prefix"...)
+	}
+
+	// p.ip is non-nil, because p is valid.
+	if p.ip.z == z4 {
+		b = p.ip.appendTo4(b)
+	} else {
+		if p.ip.Is4In6() {
+			b = append(b, "::ffff:"...)
+			b = p.ip.Unmap().appendTo4(b)
+		} else {
+			b = p.ip.appendTo6(b)
+		}
+	}
+
+	b = append(b, '/')
+	b = appendDecimal(b, uint8(p.bits))
+	return b
+}
+
+// MarshalText implements the encoding.TextMarshaler interface,
+// The encoding is the same as returned by String, with one exception:
+// If p is the zero value, the encoding is the empty string.
+func (p Prefix) MarshalText() ([]byte, error) {
+	var max int
+	switch p.ip.z {
+	case z0:
+	case z4:
+		max = len("255.255.255.255/32")
+	default:
+		max = len("ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff%enp5s0/128")
+	}
+	b := make([]byte, 0, max)
+	b = p.AppendTo(b)
+	return b, nil
+}
+
+// UnmarshalText implements the encoding.TextUnmarshaler interface.
+// The IP address is expected in a form accepted by ParsePrefix
+// or generated by MarshalText.
+func (p *Prefix) UnmarshalText(text []byte) error {
+	if len(text) == 0 {
+		*p = Prefix{}
+		return nil
+	}
+	var err error
+	*p, err = ParsePrefix(string(text))
+	return err
+}
+
+// MarshalBinary implements the encoding.BinaryMarshaler interface.
+// It returns Addr.MarshalBinary with an additional byte appended
+// containing the prefix bits.
+func (p Prefix) MarshalBinary() ([]byte, error) {
+	b := p.Addr().withoutZone().marshalBinaryWithTrailingBytes(1)
+	b[len(b)-1] = uint8(p.Bits())
+	return b, nil
+}
+
+// UnmarshalBinary implements the encoding.BinaryUnmarshaler interface.
+// It expects data in the form generated by MarshalBinary.
+func (p *Prefix) UnmarshalBinary(b []byte) error {
+	if len(b) < 1 {
+		return errors.New("unexpected slice size")
+	}
+	var addr Addr
+	err := addr.UnmarshalBinary(b[:len(b)-1])
+	if err != nil {
+		return err
+	}
+	*p = PrefixFrom(addr, int(b[len(b)-1]))
+	return nil
+}
+
+// String returns the CIDR notation of p: "<ip>/<bits>".
+func (p Prefix) String() string {
+	if !p.IsValid() {
+		return "invalid Prefix"
+	}
+	return p.ip.String() + "/" + itoa.Itoa(int(p.bits))
+}
diff --git a/contrib/go/_std_1.18/src/net/netip/uint128.go b/contrib/go/_std_1.19/src/net/netip/uint128.go
index 738939d7de..738939d7de 100644
--- a/contrib/go/_std_1.18/src/net/netip/uint128.go
+++ b/contrib/go/_std_1.19/src/net/netip/uint128.go
diff --git a/contrib/go/_std_1.19/src/net/nss.go b/contrib/go/_std_1.19/src/net/nss.go
new file mode 100644
index 0000000000..c4c608fb61
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/nss.go
@@ -0,0 +1,158 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+	"errors"
+	"internal/bytealg"
+	"io"
+	"os"
+)
+
+// nssConf represents the state of the machine's /etc/nsswitch.conf file.
+type nssConf struct {
+	err     error                  // any error encountered opening or parsing the file
+	sources map[string][]nssSource // keyed by database (e.g. "hosts")
+}
+
+type nssSource struct {
+	source   string // e.g. "compat", "files", "mdns4_minimal"
+	criteria []nssCriterion
+}
+
+// standardCriteria reports all specified criteria have the default
+// status actions.
+func (s nssSource) standardCriteria() bool {
+	for i, crit := range s.criteria {
+		if !crit.standardStatusAction(i == len(s.criteria)-1) {
+			return false
+		}
+	}
+	return true
+}
+
+// nssCriterion is the parsed structure of one of the criteria in brackets
+// after an NSS source name.
+type nssCriterion struct {
+	negate bool   // if "!" was present
+	status string // e.g. "success", "unavail" (lowercase)
+	action string // e.g. "return", "continue" (lowercase)
+}
+
+// standardStatusAction reports whether c is equivalent to not
+// specifying the criterion at all. last is whether this criteria is the
+// last in the list.
+func (c nssCriterion) standardStatusAction(last bool) bool {
+	if c.negate {
+		return false
+	}
+	var def string
+	switch c.status {
+	case "success":
+		def = "return"
+	case "notfound", "unavail", "tryagain":
+		def = "continue"
+	default:
+		// Unknown status
+		return false
+	}
+	if last && c.action == "return" {
+		return true
+	}
+	return c.action == def
+}
+
+func parseNSSConfFile(file string) *nssConf {
+	f, err := os.Open(file)
+	if err != nil {
+		return &nssConf{err: err}
+	}
+	defer f.Close()
+	return parseNSSConf(f)
+}
+
+func parseNSSConf(r io.Reader) *nssConf {
+	slurp, err := readFull(r)
+	if err != nil {
+		return &nssConf{err: err}
+	}
+	conf := new(nssConf)
+	conf.err = foreachLine(slurp, func(line []byte) error {
+		line = trimSpace(removeComment(line))
+		if len(line) == 0 {
+			return nil
+		}
+		colon := bytealg.IndexByte(line, ':')
+		if colon == -1 {
+			return errors.New("no colon on line")
+		}
+		db := string(trimSpace(line[:colon]))
+		srcs := line[colon+1:]
+		for {
+			srcs = trimSpace(srcs)
+			if len(srcs) == 0 {
+				break
+			}
+			sp := bytealg.IndexByte(srcs, ' ')
+			var src string
+			if sp == -1 {
+				src = string(srcs)
+				srcs = nil // done
+			} else {
+				src = string(srcs[:sp])
+				srcs = trimSpace(srcs[sp+1:])
+			}
+			var criteria []nssCriterion
+			// See if there's a criteria block in brackets.
+			if len(srcs) > 0 && srcs[0] == '[' {
+				bclose := bytealg.IndexByte(srcs, ']')
+				if bclose == -1 {
+					return errors.New("unclosed criterion bracket")
+				}
+				var err error
+				criteria, err = parseCriteria(srcs[1:bclose])
+				if err != nil {
+					return errors.New("invalid criteria: " + string(srcs[1:bclose]))
+				}
+				srcs = srcs[bclose+1:]
+			}
+			if conf.sources == nil {
+				conf.sources = make(map[string][]nssSource)
+			}
+			conf.sources[db] = append(conf.sources[db], nssSource{
+				source:   src,
+				criteria: criteria,
+			})
+		}
+		return nil
+	})
+	return conf
+}
+
+// parses "foo=bar !foo=bar"
+func parseCriteria(x []byte) (c []nssCriterion, err error) {
+	err = foreachField(x, func(f []byte) error {
+		not := false
+		if len(f) > 0 && f[0] == '!' {
+			not = true
+			f = f[1:]
+		}
+		if len(f) < 3 {
+			return errors.New("criterion too short")
+		}
+		eq := bytealg.IndexByte(f, '=')
+		if eq == -1 {
+			return errors.New("criterion lacks equal sign")
+		}
+		lowerASCIIBytes(f)
+		c = append(c, nssCriterion{
+			negate: not,
+			status: string(f[:eq]),
+			action: string(f[eq+1:]),
+		})
+		return nil
+	})
+	return
+}
diff --git a/contrib/go/_std_1.18/src/net/parse.go b/contrib/go/_std_1.19/src/net/parse.go
index ee2890fe2c..ee2890fe2c 100644
--- a/contrib/go/_std_1.18/src/net/parse.go
+++ b/contrib/go/_std_1.19/src/net/parse.go
diff --git a/contrib/go/_std_1.18/src/net/pipe.go b/contrib/go/_std_1.19/src/net/pipe.go
index f1741938b0..f1741938b0 100644
--- a/contrib/go/_std_1.18/src/net/pipe.go
+++ b/contrib/go/_std_1.19/src/net/pipe.go
diff --git a/contrib/go/_std_1.18/src/net/port.go b/contrib/go/_std_1.19/src/net/port.go
index 32e7628619..32e7628619 100644
--- a/contrib/go/_std_1.18/src/net/port.go
+++ b/contrib/go/_std_1.19/src/net/port.go
diff --git a/contrib/go/_std_1.19/src/net/port_unix.go b/contrib/go/_std_1.19/src/net/port_unix.go
new file mode 100644
index 0000000000..b05b588f17
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/port_unix.go
@@ -0,0 +1,57 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm)
+
+// Read system port mappings from /etc/services
+
+package net
+
+import (
+	"internal/bytealg"
+	"sync"
+)
+
+var onceReadServices sync.Once
+
+func readServices() {
+	file, err := open("/etc/services")
+	if err != nil {
+		return
+	}
+	defer file.close()
+
+	for line, ok := file.readLine(); ok; line, ok = file.readLine() {
+		// "http 80/tcp www www-http # World Wide Web HTTP"
+		if i := bytealg.IndexByteString(line, '#'); i >= 0 {
+			line = line[:i]
+		}
+		f := getFields(line)
+		if len(f) < 2 {
+			continue
+		}
+		portnet := f[1] // "80/tcp"
+		port, j, ok := dtoi(portnet)
+		if !ok || port <= 0 || j >= len(portnet) || portnet[j] != '/' {
+			continue
+		}
+		netw := portnet[j+1:] // "tcp"
+		m, ok1 := services[netw]
+		if !ok1 {
+			m = make(map[string]int)
+			services[netw] = m
+		}
+		for i := 0; i < len(f); i++ {
+			if i != 1 { // f[1] was port/net
+				m[f[i]] = port
+			}
+		}
+	}
+}
+
+// goLookupPort is the native Go implementation of LookupPort.
+func goLookupPort(network, service string) (port int, err error) {
+	onceReadServices.Do(readServices)
+	return lookupPortMap(network, service)
+}
diff --git a/contrib/go/_std_1.18/src/net/rawconn.go b/contrib/go/_std_1.19/src/net/rawconn.go
index c786354582..c786354582 100644
--- a/contrib/go/_std_1.18/src/net/rawconn.go
+++ b/contrib/go/_std_1.19/src/net/rawconn.go
diff --git a/contrib/go/_std_1.18/src/net/sendfile_linux.go b/contrib/go/_std_1.19/src/net/sendfile_linux.go
index e5150aa5e8..e5150aa5e8 100644
--- a/contrib/go/_std_1.18/src/net/sendfile_linux.go
+++ b/contrib/go/_std_1.19/src/net/sendfile_linux.go
diff --git a/contrib/go/_std_1.18/src/net/sendfile_unix_alt.go b/contrib/go/_std_1.19/src/net/sendfile_unix_alt.go
index f99af92bc8..f99af92bc8 100644
--- a/contrib/go/_std_1.18/src/net/sendfile_unix_alt.go
+++ b/contrib/go/_std_1.19/src/net/sendfile_unix_alt.go
diff --git a/contrib/go/_std_1.18/src/net/sock_bsd.go b/contrib/go/_std_1.19/src/net/sock_bsd.go
index 27daf722b5..27daf722b5 100644
--- a/contrib/go/_std_1.18/src/net/sock_bsd.go
+++ b/contrib/go/_std_1.19/src/net/sock_bsd.go
diff --git a/contrib/go/_std_1.19/src/net/sock_cloexec.go b/contrib/go/_std_1.19/src/net/sock_cloexec.go
new file mode 100644
index 0000000000..3f1cc9827a
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/sock_cloexec.go
@@ -0,0 +1,25 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements sysSocket for platforms that provide a fast path for
+// setting SetNonblock and CloseOnExec.
+
+//go:build dragonfly || freebsd || linux || netbsd || openbsd || solaris
+
+package net
+
+import (
+	"os"
+	"syscall"
+)
+
+// Wrapper around the socket system call that marks the returned file
+// descriptor as nonblocking and close-on-exec.
+func sysSocket(family, sotype, proto int) (int, error) {
+	s, err := socketFunc(family, sotype|syscall.SOCK_NONBLOCK|syscall.SOCK_CLOEXEC, proto)
+	if err != nil {
+		return -1, os.NewSyscallError("socket", err)
+	}
+	return s, nil
+}
diff --git a/contrib/go/_std_1.19/src/net/sock_linux.go b/contrib/go/_std_1.19/src/net/sock_linux.go
new file mode 100644
index 0000000000..2513f9ba7b
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/sock_linux.go
@@ -0,0 +1,86 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import "syscall"
+
+func kernelVersion() (major int, minor int) {
+	var uname syscall.Utsname
+	if err := syscall.Uname(&uname); err != nil {
+		return
+	}
+
+	rl := uname.Release
+	var values [2]int
+	vi := 0
+	value := 0
+	for _, c := range rl {
+		if c >= '0' && c <= '9' {
+			value = (value * 10) + int(c-'0')
+		} else {
+			// Note that we're assuming N.N.N here.  If we see anything else we are likely to
+			// mis-parse it.
+			values[vi] = value
+			vi++
+			if vi >= len(values) {
+				break
+			}
+			value = 0
+		}
+	}
+	switch vi {
+	case 0:
+		return 0, 0
+	case 1:
+		return values[0], 0
+	case 2:
+		return values[0], values[1]
+	}
+	return
+}
+
+// Linux stores the backlog as:
+//
+//   - uint16 in kernel version < 4.1,
+//   - uint32 in kernel version >= 4.1
+//
+// Truncate number to avoid wrapping.
+//
+// See issue 5030 and 41470.
+func maxAckBacklog(n int) int {
+	major, minor := kernelVersion()
+	size := 16
+	if major > 4 || (major == 4 && minor >= 1) {
+		size = 32
+	}
+
+	var max uint = 1<<size - 1
+	if uint(n) > max {
+		n = int(max)
+	}
+	return n
+}
+
+func maxListenerBacklog() int {
+	fd, err := open("/proc/sys/net/core/somaxconn")
+	if err != nil {
+		return syscall.SOMAXCONN
+	}
+	defer fd.close()
+	l, ok := fd.readLine()
+	if !ok {
+		return syscall.SOMAXCONN
+	}
+	f := getFields(l)
+	n, _, ok := dtoi(f[0])
+	if n == 0 || !ok {
+		return syscall.SOMAXCONN
+	}
+
+	if n > 1<<16-1 {
+		return maxAckBacklog(n)
+	}
+	return n
+}
diff --git a/contrib/go/_std_1.19/src/net/sock_posix.go b/contrib/go/_std_1.19/src/net/sock_posix.go
new file mode 100644
index 0000000000..4431c3a6b3
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/sock_posix.go
@@ -0,0 +1,254 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || windows
+
+package net
+
+import (
+	"context"
+	"internal/poll"
+	"os"
+	"syscall"
+)
+
+// socket returns a network file descriptor that is ready for
+// asynchronous I/O using the network poller.
+func socket(ctx context.Context, net string, family, sotype, proto int, ipv6only bool, laddr, raddr sockaddr, ctrlFn func(string, string, syscall.RawConn) error) (fd *netFD, err error) {
+	s, err := sysSocket(family, sotype, proto)
+	if err != nil {
+		return nil, err
+	}
+	if err = setDefaultSockopts(s, family, sotype, ipv6only); err != nil {
+		poll.CloseFunc(s)
+		return nil, err
+	}
+	if fd, err = newFD(s, family, sotype, net); err != nil {
+		poll.CloseFunc(s)
+		return nil, err
+	}
+
+	// This function makes a network file descriptor for the
+	// following applications:
+	//
+	// - An endpoint holder that opens a passive stream
+	//   connection, known as a stream listener
+	//
+	// - An endpoint holder that opens a destination-unspecific
+	//   datagram connection, known as a datagram listener
+	//
+	// - An endpoint holder that opens an active stream or a
+	//   destination-specific datagram connection, known as a
+	//   dialer
+	//
+	// - An endpoint holder that opens the other connection, such
+	//   as talking to the protocol stack inside the kernel
+	//
+	// For stream and datagram listeners, they will only require
+	// named sockets, so we can assume that it's just a request
+	// from stream or datagram listeners when laddr is not nil but
+	// raddr is nil. Otherwise we assume it's just for dialers or
+	// the other connection holders.
+
+	if laddr != nil && raddr == nil {
+		switch sotype {
+		case syscall.SOCK_STREAM, syscall.SOCK_SEQPACKET:
+			if err := fd.listenStream(laddr, listenerBacklog(), ctrlFn); err != nil {
+				fd.Close()
+				return nil, err
+			}
+			return fd, nil
+		case syscall.SOCK_DGRAM:
+			if err := fd.listenDatagram(laddr, ctrlFn); err != nil {
+				fd.Close()
+				return nil, err
+			}
+			return fd, nil
+		}
+	}
+	if err := fd.dial(ctx, laddr, raddr, ctrlFn); err != nil {
+		fd.Close()
+		return nil, err
+	}
+	return fd, nil
+}
+
+func (fd *netFD) ctrlNetwork() string {
+	switch fd.net {
+	case "unix", "unixgram", "unixpacket":
+		return fd.net
+	}
+	switch fd.net[len(fd.net)-1] {
+	case '4', '6':
+		return fd.net
+	}
+	if fd.family == syscall.AF_INET {
+		return fd.net + "4"
+	}
+	return fd.net + "6"
+}
+
+func (fd *netFD) addrFunc() func(syscall.Sockaddr) Addr {
+	switch fd.family {
+	case syscall.AF_INET, syscall.AF_INET6:
+		switch fd.sotype {
+		case syscall.SOCK_STREAM:
+			return sockaddrToTCP
+		case syscall.SOCK_DGRAM:
+			return sockaddrToUDP
+		case syscall.SOCK_RAW:
+			return sockaddrToIP
+		}
+	case syscall.AF_UNIX:
+		switch fd.sotype {
+		case syscall.SOCK_STREAM:
+			return sockaddrToUnix
+		case syscall.SOCK_DGRAM:
+			return sockaddrToUnixgram
+		case syscall.SOCK_SEQPACKET:
+			return sockaddrToUnixpacket
+		}
+	}
+	return func(syscall.Sockaddr) Addr { return nil }
+}
+
+func (fd *netFD) dial(ctx context.Context, laddr, raddr sockaddr, ctrlFn func(string, string, syscall.RawConn) error) error {
+	if ctrlFn != nil {
+		c, err := newRawConn(fd)
+		if err != nil {
+			return err
+		}
+		var ctrlAddr string
+		if raddr != nil {
+			ctrlAddr = raddr.String()
+		} else if laddr != nil {
+			ctrlAddr = laddr.String()
+		}
+		if err := ctrlFn(fd.ctrlNetwork(), ctrlAddr, c); err != nil {
+			return err
+		}
+	}
+	var err error
+	var lsa syscall.Sockaddr
+	if laddr != nil {
+		if lsa, err = laddr.sockaddr(fd.family); err != nil {
+			return err
+		} else if lsa != nil {
+			if err = syscall.Bind(fd.pfd.Sysfd, lsa); err != nil {
+				return os.NewSyscallError("bind", err)
+			}
+		}
+	}
+	var rsa syscall.Sockaddr  // remote address from the user
+	var crsa syscall.Sockaddr // remote address we actually connected to
+	if raddr != nil {
+		if rsa, err = raddr.sockaddr(fd.family); err != nil {
+			return err
+		}
+		if crsa, err = fd.connect(ctx, lsa, rsa); err != nil {
+			return err
+		}
+		fd.isConnected = true
+	} else {
+		if err := fd.init(); err != nil {
+			return err
+		}
+	}
+	// Record the local and remote addresses from the actual socket.
+	// Get the local address by calling Getsockname.
+	// For the remote address, use
+	// 1) the one returned by the connect method, if any; or
+	// 2) the one from Getpeername, if it succeeds; or
+	// 3) the one passed to us as the raddr parameter.
+	lsa, _ = syscall.Getsockname(fd.pfd.Sysfd)
+	if crsa != nil {
+		fd.setAddr(fd.addrFunc()(lsa), fd.addrFunc()(crsa))
+	} else if rsa, _ = syscall.Getpeername(fd.pfd.Sysfd); rsa != nil {
+		fd.setAddr(fd.addrFunc()(lsa), fd.addrFunc()(rsa))
+	} else {
+		fd.setAddr(fd.addrFunc()(lsa), raddr)
+	}
+	return nil
+}
+
+func (fd *netFD) listenStream(laddr sockaddr, backlog int, ctrlFn func(string, string, syscall.RawConn) error) error {
+	var err error
+	if err = setDefaultListenerSockopts(fd.pfd.Sysfd); err != nil {
+		return err
+	}
+	var lsa syscall.Sockaddr
+	if lsa, err = laddr.sockaddr(fd.family); err != nil {
+		return err
+	}
+	if ctrlFn != nil {
+		c, err := newRawConn(fd)
+		if err != nil {
+			return err
+		}
+		if err := ctrlFn(fd.ctrlNetwork(), laddr.String(), c); err != nil {
+			return err
+		}
+	}
+	if err = syscall.Bind(fd.pfd.Sysfd, lsa); err != nil {
+		return os.NewSyscallError("bind", err)
+	}
+	if err = listenFunc(fd.pfd.Sysfd, backlog); err != nil {
+		return os.NewSyscallError("listen", err)
+	}
+	if err = fd.init(); err != nil {
+		return err
+	}
+	lsa, _ = syscall.Getsockname(fd.pfd.Sysfd)
+	fd.setAddr(fd.addrFunc()(lsa), nil)
+	return nil
+}
+
+func (fd *netFD) listenDatagram(laddr sockaddr, ctrlFn func(string, string, syscall.RawConn) error) error {
+	switch addr := laddr.(type) {
+	case *UDPAddr:
+		// We provide a socket that listens to a wildcard
+		// address with reusable UDP port when the given laddr
+		// is an appropriate UDP multicast address prefix.
+		// This makes it possible for a single UDP listener to
+		// join multiple different group addresses, for
+		// multiple UDP listeners that listen on the same UDP
+		// port to join the same group address.
+		if addr.IP != nil && addr.IP.IsMulticast() {
+			if err := setDefaultMulticastSockopts(fd.pfd.Sysfd); err != nil {
+				return err
+			}
+			addr := *addr
+			switch fd.family {
+			case syscall.AF_INET:
+				addr.IP = IPv4zero
+			case syscall.AF_INET6:
+				addr.IP = IPv6unspecified
+			}
+			laddr = &addr
+		}
+	}
+	var err error
+	var lsa syscall.Sockaddr
+	if lsa, err = laddr.sockaddr(fd.family); err != nil {
+		return err
+	}
+	if ctrlFn != nil {
+		c, err := newRawConn(fd)
+		if err != nil {
+			return err
+		}
+		if err := ctrlFn(fd.ctrlNetwork(), laddr.String(), c); err != nil {
+			return err
+		}
+	}
+	if err = syscall.Bind(fd.pfd.Sysfd, lsa); err != nil {
+		return os.NewSyscallError("bind", err)
+	}
+	if err = fd.init(); err != nil {
+		return err
+	}
+	lsa, _ = syscall.Getsockname(fd.pfd.Sysfd)
+	fd.setAddr(fd.addrFunc()(lsa), nil)
+	return nil
+}
diff --git a/contrib/go/_std_1.19/src/net/sockaddr_posix.go b/contrib/go/_std_1.19/src/net/sockaddr_posix.go
new file mode 100644
index 0000000000..76c3233b29
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/sockaddr_posix.go
@@ -0,0 +1,34 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm) || windows
+
+package net
+
+import (
+	"syscall"
+)
+
+// A sockaddr represents a TCP, UDP, IP or Unix network endpoint
+// address that can be converted into a syscall.Sockaddr.
+type sockaddr interface {
+	Addr
+
+	// family returns the platform-dependent address family
+	// identifier.
+	family() int
+
+	// isWildcard reports whether the address is a wildcard
+	// address.
+	isWildcard() bool
+
+	// sockaddr returns the address converted into a syscall
+	// sockaddr type that implements syscall.Sockaddr
+	// interface. It returns a nil interface when the address is
+	// nil.
+	sockaddr(family int) (syscall.Sockaddr, error)
+
+	// toLocal maps the zero address to a local system address (127.0.0.1 or ::1)
+	toLocal(net string) sockaddr
+}
diff --git a/contrib/go/_std_1.18/src/net/sockopt_bsd.go b/contrib/go/_std_1.19/src/net/sockopt_bsd.go
index ff99811980..ff99811980 100644
--- a/contrib/go/_std_1.18/src/net/sockopt_bsd.go
+++ b/contrib/go/_std_1.19/src/net/sockopt_bsd.go
diff --git a/contrib/go/_std_1.18/src/net/sockopt_linux.go b/contrib/go/_std_1.19/src/net/sockopt_linux.go
index 3d544299ac..3d544299ac 100644
--- a/contrib/go/_std_1.18/src/net/sockopt_linux.go
+++ b/contrib/go/_std_1.19/src/net/sockopt_linux.go
diff --git a/contrib/go/_std_1.19/src/net/sockopt_posix.go b/contrib/go/_std_1.19/src/net/sockopt_posix.go
new file mode 100644
index 0000000000..32e8fcd505
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/sockopt_posix.go
@@ -0,0 +1,134 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || windows
+
+package net
+
+import (
+	"internal/bytealg"
+	"runtime"
+	"syscall"
+)
+
+// Boolean to int.
+func boolint(b bool) int {
+	if b {
+		return 1
+	}
+	return 0
+}
+
+func ipv4AddrToInterface(ip IP) (*Interface, error) {
+	ift, err := Interfaces()
+	if err != nil {
+		return nil, err
+	}
+	for _, ifi := range ift {
+		ifat, err := ifi.Addrs()
+		if err != nil {
+			return nil, err
+		}
+		for _, ifa := range ifat {
+			switch v := ifa.(type) {
+			case *IPAddr:
+				if ip.Equal(v.IP) {
+					return &ifi, nil
+				}
+			case *IPNet:
+				if ip.Equal(v.IP) {
+					return &ifi, nil
+				}
+			}
+		}
+	}
+	if ip.Equal(IPv4zero) {
+		return nil, nil
+	}
+	return nil, errNoSuchInterface
+}
+
+func interfaceToIPv4Addr(ifi *Interface) (IP, error) {
+	if ifi == nil {
+		return IPv4zero, nil
+	}
+	ifat, err := ifi.Addrs()
+	if err != nil {
+		return nil, err
+	}
+	for _, ifa := range ifat {
+		switch v := ifa.(type) {
+		case *IPAddr:
+			if v.IP.To4() != nil {
+				return v.IP, nil
+			}
+		case *IPNet:
+			if v.IP.To4() != nil {
+				return v.IP, nil
+			}
+		}
+	}
+	return nil, errNoSuchInterface
+}
+
+func setIPv4MreqToInterface(mreq *syscall.IPMreq, ifi *Interface) error {
+	if ifi == nil {
+		return nil
+	}
+	ifat, err := ifi.Addrs()
+	if err != nil {
+		return err
+	}
+	for _, ifa := range ifat {
+		switch v := ifa.(type) {
+		case *IPAddr:
+			if a := v.IP.To4(); a != nil {
+				copy(mreq.Interface[:], a)
+				goto done
+			}
+		case *IPNet:
+			if a := v.IP.To4(); a != nil {
+				copy(mreq.Interface[:], a)
+				goto done
+			}
+		}
+	}
+done:
+	if bytealg.Equal(mreq.Multiaddr[:], IPv4zero.To4()) {
+		return errNoSuchMulticastInterface
+	}
+	return nil
+}
+
+func setReadBuffer(fd *netFD, bytes int) error {
+	err := fd.pfd.SetsockoptInt(syscall.SOL_SOCKET, syscall.SO_RCVBUF, bytes)
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
+}
+
+func setWriteBuffer(fd *netFD, bytes int) error {
+	err := fd.pfd.SetsockoptInt(syscall.SOL_SOCKET, syscall.SO_SNDBUF, bytes)
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
+}
+
+func setKeepAlive(fd *netFD, keepalive bool) error {
+	err := fd.pfd.SetsockoptInt(syscall.SOL_SOCKET, syscall.SO_KEEPALIVE, boolint(keepalive))
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
+}
+
+func setLinger(fd *netFD, sec int) error {
+	var l syscall.Linger
+	if sec >= 0 {
+		l.Onoff = 1
+		l.Linger = int32(sec)
+	} else {
+		l.Onoff = 0
+		l.Linger = 0
+	}
+	err := fd.pfd.SetsockoptLinger(syscall.SOL_SOCKET, syscall.SO_LINGER, &l)
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
+}
diff --git a/contrib/go/_std_1.18/src/net/sockoptip_bsdvar.go b/contrib/go/_std_1.19/src/net/sockoptip_bsdvar.go
index 3e9ba1ee78..3e9ba1ee78 100644
--- a/contrib/go/_std_1.18/src/net/sockoptip_bsdvar.go
+++ b/contrib/go/_std_1.19/src/net/sockoptip_bsdvar.go
diff --git a/contrib/go/_std_1.18/src/net/sockoptip_linux.go b/contrib/go/_std_1.19/src/net/sockoptip_linux.go
index bd7d834425..bd7d834425 100644
--- a/contrib/go/_std_1.18/src/net/sockoptip_linux.go
+++ b/contrib/go/_std_1.19/src/net/sockoptip_linux.go
diff --git a/contrib/go/_std_1.19/src/net/sockoptip_posix.go b/contrib/go/_std_1.19/src/net/sockoptip_posix.go
new file mode 100644
index 0000000000..572ea455c0
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/sockoptip_posix.go
@@ -0,0 +1,49 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || windows
+
+package net
+
+import (
+	"runtime"
+	"syscall"
+)
+
+func joinIPv4Group(fd *netFD, ifi *Interface, ip IP) error {
+	mreq := &syscall.IPMreq{Multiaddr: [4]byte{ip[0], ip[1], ip[2], ip[3]}}
+	if err := setIPv4MreqToInterface(mreq, ifi); err != nil {
+		return err
+	}
+	err := fd.pfd.SetsockoptIPMreq(syscall.IPPROTO_IP, syscall.IP_ADD_MEMBERSHIP, mreq)
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
+}
+
+func setIPv6MulticastInterface(fd *netFD, ifi *Interface) error {
+	var v int
+	if ifi != nil {
+		v = ifi.Index
+	}
+	err := fd.pfd.SetsockoptInt(syscall.IPPROTO_IPV6, syscall.IPV6_MULTICAST_IF, v)
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
+}
+
+func setIPv6MulticastLoopback(fd *netFD, v bool) error {
+	err := fd.pfd.SetsockoptInt(syscall.IPPROTO_IPV6, syscall.IPV6_MULTICAST_LOOP, boolint(v))
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
+}
+
+func joinIPv6Group(fd *netFD, ifi *Interface, ip IP) error {
+	mreq := &syscall.IPv6Mreq{}
+	copy(mreq.Multiaddr[:], ip)
+	if ifi != nil {
+		mreq.Interface = uint32(ifi.Index)
+	}
+	err := fd.pfd.SetsockoptIPv6Mreq(syscall.IPPROTO_IPV6, syscall.IPV6_JOIN_GROUP, mreq)
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
+}
diff --git a/contrib/go/_std_1.18/src/net/splice_linux.go b/contrib/go/_std_1.19/src/net/splice_linux.go
index 69c3f65770..69c3f65770 100644
--- a/contrib/go/_std_1.18/src/net/splice_linux.go
+++ b/contrib/go/_std_1.19/src/net/splice_linux.go
diff --git a/contrib/go/_std_1.18/src/net/splice_stub.go b/contrib/go/_std_1.19/src/net/splice_stub.go
index 3cdadb11c5..3cdadb11c5 100644
--- a/contrib/go/_std_1.18/src/net/splice_stub.go
+++ b/contrib/go/_std_1.19/src/net/splice_stub.go
diff --git a/contrib/go/_std_1.19/src/net/sys_cloexec.go b/contrib/go/_std_1.19/src/net/sys_cloexec.go
new file mode 100644
index 0000000000..6e61d40c19
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/sys_cloexec.go
@@ -0,0 +1,36 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements sysSocket for platforms that do not provide a fast path
+// for setting SetNonblock and CloseOnExec.
+
+//go:build aix || darwin
+
+package net
+
+import (
+	"internal/poll"
+	"os"
+	"syscall"
+)
+
+// Wrapper around the socket system call that marks the returned file
+// descriptor as nonblocking and close-on-exec.
+func sysSocket(family, sotype, proto int) (int, error) {
+	// See ../syscall/exec_unix.go for description of ForkLock.
+	syscall.ForkLock.RLock()
+	s, err := socketFunc(family, sotype, proto)
+	if err == nil {
+		syscall.CloseOnExec(s)
+	}
+	syscall.ForkLock.RUnlock()
+	if err != nil {
+		return -1, os.NewSyscallError("socket", err)
+	}
+	if err = syscall.SetNonblock(s, true); err != nil {
+		poll.CloseFunc(s)
+		return -1, os.NewSyscallError("setnonblock", err)
+	}
+	return s, nil
+}
diff --git a/contrib/go/_std_1.18/src/net/tcpsock.go b/contrib/go/_std_1.19/src/net/tcpsock.go
index 6bad0e8f8b..6bad0e8f8b 100644
--- a/contrib/go/_std_1.18/src/net/tcpsock.go
+++ b/contrib/go/_std_1.19/src/net/tcpsock.go
diff --git a/contrib/go/_std_1.19/src/net/tcpsock_posix.go b/contrib/go/_std_1.19/src/net/tcpsock_posix.go
new file mode 100644
index 0000000000..1c91170c50
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/tcpsock_posix.go
@@ -0,0 +1,176 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm) || windows
+
+package net
+
+import (
+	"context"
+	"io"
+	"os"
+	"syscall"
+)
+
+func sockaddrToTCP(sa syscall.Sockaddr) Addr {
+	switch sa := sa.(type) {
+	case *syscall.SockaddrInet4:
+		return &TCPAddr{IP: sa.Addr[0:], Port: sa.Port}
+	case *syscall.SockaddrInet6:
+		return &TCPAddr{IP: sa.Addr[0:], Port: sa.Port, Zone: zoneCache.name(int(sa.ZoneId))}
+	}
+	return nil
+}
+
+func (a *TCPAddr) family() int {
+	if a == nil || len(a.IP) <= IPv4len {
+		return syscall.AF_INET
+	}
+	if a.IP.To4() != nil {
+		return syscall.AF_INET
+	}
+	return syscall.AF_INET6
+}
+
+func (a *TCPAddr) sockaddr(family int) (syscall.Sockaddr, error) {
+	if a == nil {
+		return nil, nil
+	}
+	return ipToSockaddr(family, a.IP, a.Port, a.Zone)
+}
+
+func (a *TCPAddr) toLocal(net string) sockaddr {
+	return &TCPAddr{loopbackIP(net), a.Port, a.Zone}
+}
+
+func (c *TCPConn) readFrom(r io.Reader) (int64, error) {
+	if n, err, handled := splice(c.fd, r); handled {
+		return n, err
+	}
+	if n, err, handled := sendFile(c.fd, r); handled {
+		return n, err
+	}
+	return genericReadFrom(c, r)
+}
+
+func (sd *sysDialer) dialTCP(ctx context.Context, laddr, raddr *TCPAddr) (*TCPConn, error) {
+	if h := sd.testHookDialTCP; h != nil {
+		return h(ctx, sd.network, laddr, raddr)
+	}
+	if h := testHookDialTCP; h != nil {
+		return h(ctx, sd.network, laddr, raddr)
+	}
+	return sd.doDialTCP(ctx, laddr, raddr)
+}
+
+func (sd *sysDialer) doDialTCP(ctx context.Context, laddr, raddr *TCPAddr) (*TCPConn, error) {
+	fd, err := internetSocket(ctx, sd.network, laddr, raddr, syscall.SOCK_STREAM, 0, "dial", sd.Dialer.Control)
+
+	// TCP has a rarely used mechanism called a 'simultaneous connection' in
+	// which Dial("tcp", addr1, addr2) run on the machine at addr1 can
+	// connect to a simultaneous Dial("tcp", addr2, addr1) run on the machine
+	// at addr2, without either machine executing Listen. If laddr == nil,
+	// it means we want the kernel to pick an appropriate originating local
+	// address. Some Linux kernels cycle blindly through a fixed range of
+	// local ports, regardless of destination port. If a kernel happens to
+	// pick local port 50001 as the source for a Dial("tcp", "", "localhost:50001"),
+	// then the Dial will succeed, having simultaneously connected to itself.
+	// This can only happen when we are letting the kernel pick a port (laddr == nil)
+	// and when there is no listener for the destination address.
+	// It's hard to argue this is anything other than a kernel bug. If we
+	// see this happen, rather than expose the buggy effect to users, we
+	// close the fd and try again. If it happens twice more, we relent and
+	// use the result. See also:
+	//	https://golang.org/issue/2690
+	//	https://stackoverflow.com/questions/4949858/
+	//
+	// The opposite can also happen: if we ask the kernel to pick an appropriate
+	// originating local address, sometimes it picks one that is already in use.
+	// So if the error is EADDRNOTAVAIL, we have to try again too, just for
+	// a different reason.
+	//
+	// The kernel socket code is no doubt enjoying watching us squirm.
+	for i := 0; i < 2 && (laddr == nil || laddr.Port == 0) && (selfConnect(fd, err) || spuriousENOTAVAIL(err)); i++ {
+		if err == nil {
+			fd.Close()
+		}
+		fd, err = internetSocket(ctx, sd.network, laddr, raddr, syscall.SOCK_STREAM, 0, "dial", sd.Dialer.Control)
+	}
+
+	if err != nil {
+		return nil, err
+	}
+	return newTCPConn(fd), nil
+}
+
+func selfConnect(fd *netFD, err error) bool {
+	// If the connect failed, we clearly didn't connect to ourselves.
+	if err != nil {
+		return false
+	}
+
+	// The socket constructor can return an fd with raddr nil under certain
+	// unknown conditions. The errors in the calls there to Getpeername
+	// are discarded, but we can't catch the problem there because those
+	// calls are sometimes legally erroneous with a "socket not connected".
+	// Since this code (selfConnect) is already trying to work around
+	// a problem, we make sure if this happens we recognize trouble and
+	// ask the DialTCP routine to try again.
+	// TODO: try to understand what's really going on.
+	if fd.laddr == nil || fd.raddr == nil {
+		return true
+	}
+	l := fd.laddr.(*TCPAddr)
+	r := fd.raddr.(*TCPAddr)
+	return l.Port == r.Port && l.IP.Equal(r.IP)
+}
+
+func spuriousENOTAVAIL(err error) bool {
+	if op, ok := err.(*OpError); ok {
+		err = op.Err
+	}
+	if sys, ok := err.(*os.SyscallError); ok {
+		err = sys.Err
+	}
+	return err == syscall.EADDRNOTAVAIL
+}
+
+func (ln *TCPListener) ok() bool { return ln != nil && ln.fd != nil }
+
+func (ln *TCPListener) accept() (*TCPConn, error) {
+	fd, err := ln.fd.accept()
+	if err != nil {
+		return nil, err
+	}
+	tc := newTCPConn(fd)
+	if ln.lc.KeepAlive >= 0 {
+		setKeepAlive(fd, true)
+		ka := ln.lc.KeepAlive
+		if ln.lc.KeepAlive == 0 {
+			ka = defaultTCPKeepAlive
+		}
+		setKeepAlivePeriod(fd, ka)
+	}
+	return tc, nil
+}
+
+func (ln *TCPListener) close() error {
+	return ln.fd.Close()
+}
+
+func (ln *TCPListener) file() (*os.File, error) {
+	f, err := ln.fd.dup()
+	if err != nil {
+		return nil, err
+	}
+	return f, nil
+}
+
+func (sl *sysListener) listenTCP(ctx context.Context, laddr *TCPAddr) (*TCPListener, error) {
+	fd, err := internetSocket(ctx, sl.network, laddr, nil, syscall.SOCK_STREAM, 0, "listen", sl.ListenConfig.Control)
+	if err != nil {
+		return nil, err
+	}
+	return &TCPListener{fd: fd, lc: sl.ListenConfig}, nil
+}
diff --git a/contrib/go/_std_1.18/src/net/tcpsockopt_darwin.go b/contrib/go/_std_1.19/src/net/tcpsockopt_darwin.go
index 53c6756e33..53c6756e33 100644
--- a/contrib/go/_std_1.18/src/net/tcpsockopt_darwin.go
+++ b/contrib/go/_std_1.19/src/net/tcpsockopt_darwin.go
diff --git a/contrib/go/_std_1.19/src/net/tcpsockopt_posix.go b/contrib/go/_std_1.19/src/net/tcpsockopt_posix.go
new file mode 100644
index 0000000000..d708f04875
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/tcpsockopt_posix.go
@@ -0,0 +1,18 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || windows
+
+package net
+
+import (
+	"runtime"
+	"syscall"
+)
+
+func setNoDelay(fd *netFD, noDelay bool) error {
+	err := fd.pfd.SetsockoptInt(syscall.IPPROTO_TCP, syscall.TCP_NODELAY, boolint(noDelay))
+	runtime.KeepAlive(fd)
+	return wrapSyscallError("setsockopt", err)
+}
diff --git a/contrib/go/_std_1.18/src/net/tcpsockopt_unix.go b/contrib/go/_std_1.19/src/net/tcpsockopt_unix.go
index bdcdc40239..bdcdc40239 100644
--- a/contrib/go/_std_1.18/src/net/tcpsockopt_unix.go
+++ b/contrib/go/_std_1.19/src/net/tcpsockopt_unix.go
diff --git a/contrib/go/_std_1.18/src/net/textproto/header.go b/contrib/go/_std_1.19/src/net/textproto/header.go
index a58df7aebc..a58df7aebc 100644
--- a/contrib/go/_std_1.18/src/net/textproto/header.go
+++ b/contrib/go/_std_1.19/src/net/textproto/header.go
diff --git a/contrib/go/_std_1.18/src/net/textproto/pipeline.go b/contrib/go/_std_1.19/src/net/textproto/pipeline.go
index 1928a306bf..1928a306bf 100644
--- a/contrib/go/_std_1.18/src/net/textproto/pipeline.go
+++ b/contrib/go/_std_1.19/src/net/textproto/pipeline.go
diff --git a/contrib/go/_std_1.19/src/net/textproto/reader.go b/contrib/go/_std_1.19/src/net/textproto/reader.go
new file mode 100644
index 0000000000..1f7afc5766
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/textproto/reader.go
@@ -0,0 +1,788 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package textproto
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"io"
+	"strconv"
+	"strings"
+	"sync"
+)
+
+// A Reader implements convenience methods for reading requests
+// or responses from a text protocol network connection.
+type Reader struct {
+	R   *bufio.Reader
+	dot *dotReader
+	buf []byte // a re-usable buffer for readContinuedLineSlice
+}
+
+// NewReader returns a new Reader reading from r.
+//
+// To avoid denial of service attacks, the provided bufio.Reader
+// should be reading from an io.LimitReader or similar Reader to bound
+// the size of responses.
+func NewReader(r *bufio.Reader) *Reader {
+	return &Reader{R: r}
+}
+
+// ReadLine reads a single line from r,
+// eliding the final \n or \r\n from the returned string.
+func (r *Reader) ReadLine() (string, error) {
+	line, err := r.readLineSlice()
+	return string(line), err
+}
+
+// ReadLineBytes is like ReadLine but returns a []byte instead of a string.
+func (r *Reader) ReadLineBytes() ([]byte, error) {
+	line, err := r.readLineSlice()
+	if line != nil {
+		buf := make([]byte, len(line))
+		copy(buf, line)
+		line = buf
+	}
+	return line, err
+}
+
+func (r *Reader) readLineSlice() ([]byte, error) {
+	r.closeDot()
+	var line []byte
+	for {
+		l, more, err := r.R.ReadLine()
+		if err != nil {
+			return nil, err
+		}
+		// Avoid the copy if the first call produced a full line.
+		if line == nil && !more {
+			return l, nil
+		}
+		line = append(line, l...)
+		if !more {
+			break
+		}
+	}
+	return line, nil
+}
+
+// ReadContinuedLine reads a possibly continued line from r,
+// eliding the final trailing ASCII white space.
+// Lines after the first are considered continuations if they
+// begin with a space or tab character. In the returned data,
+// continuation lines are separated from the previous line
+// only by a single space: the newline and leading white space
+// are removed.
+//
+// For example, consider this input:
+//
+//	Line 1
+//	  continued...
+//	Line 2
+//
+// The first call to ReadContinuedLine will return "Line 1 continued..."
+// and the second will return "Line 2".
+//
+// Empty lines are never continued.
+func (r *Reader) ReadContinuedLine() (string, error) {
+	line, err := r.readContinuedLineSlice(noValidation)
+	return string(line), err
+}
+
+// trim returns s with leading and trailing spaces and tabs removed.
+// It does not assume Unicode or UTF-8.
+func trim(s []byte) []byte {
+	i := 0
+	for i < len(s) && (s[i] == ' ' || s[i] == '\t') {
+		i++
+	}
+	n := len(s)
+	for n > i && (s[n-1] == ' ' || s[n-1] == '\t') {
+		n--
+	}
+	return s[i:n]
+}
+
+// ReadContinuedLineBytes is like ReadContinuedLine but
+// returns a []byte instead of a string.
+func (r *Reader) ReadContinuedLineBytes() ([]byte, error) {
+	line, err := r.readContinuedLineSlice(noValidation)
+	if line != nil {
+		buf := make([]byte, len(line))
+		copy(buf, line)
+		line = buf
+	}
+	return line, err
+}
+
+// readContinuedLineSlice reads continued lines from the reader buffer,
+// returning a byte slice with all lines. The validateFirstLine function
+// is run on the first read line, and if it returns an error then this
+// error is returned from readContinuedLineSlice.
+func (r *Reader) readContinuedLineSlice(validateFirstLine func([]byte) error) ([]byte, error) {
+	if validateFirstLine == nil {
+		return nil, fmt.Errorf("missing validateFirstLine func")
+	}
+
+	// Read the first line.
+	line, err := r.readLineSlice()
+	if err != nil {
+		return nil, err
+	}
+	if len(line) == 0 { // blank line - no continuation
+		return line, nil
+	}
+
+	if err := validateFirstLine(line); err != nil {
+		return nil, err
+	}
+
+	// Optimistically assume that we have started to buffer the next line
+	// and it starts with an ASCII letter (the next header key), or a blank
+	// line, so we can avoid copying that buffered data around in memory
+	// and skipping over non-existent whitespace.
+	if r.R.Buffered() > 1 {
+		peek, _ := r.R.Peek(2)
+		if len(peek) > 0 && (isASCIILetter(peek[0]) || peek[0] == '\n') ||
+			len(peek) == 2 && peek[0] == '\r' && peek[1] == '\n' {
+			return trim(line), nil
+		}
+	}
+
+	// ReadByte or the next readLineSlice will flush the read buffer;
+	// copy the slice into buf.
+	r.buf = append(r.buf[:0], trim(line)...)
+
+	// Read continuation lines.
+	for r.skipSpace() > 0 {
+		line, err := r.readLineSlice()
+		if err != nil {
+			break
+		}
+		r.buf = append(r.buf, ' ')
+		r.buf = append(r.buf, trim(line)...)
+	}
+	return r.buf, nil
+}
+
+// skipSpace skips R over all spaces and returns the number of bytes skipped.
+func (r *Reader) skipSpace() int {
+	n := 0
+	for {
+		c, err := r.R.ReadByte()
+		if err != nil {
+			// Bufio will keep err until next read.
+			break
+		}
+		if c != ' ' && c != '\t' {
+			r.R.UnreadByte()
+			break
+		}
+		n++
+	}
+	return n
+}
+
+func (r *Reader) readCodeLine(expectCode int) (code int, continued bool, message string, err error) {
+	line, err := r.ReadLine()
+	if err != nil {
+		return
+	}
+	return parseCodeLine(line, expectCode)
+}
+
+func parseCodeLine(line string, expectCode int) (code int, continued bool, message string, err error) {
+	if len(line) < 4 || line[3] != ' ' && line[3] != '-' {
+		err = ProtocolError("short response: " + line)
+		return
+	}
+	continued = line[3] == '-'
+	code, err = strconv.Atoi(line[0:3])
+	if err != nil || code < 100 {
+		err = ProtocolError("invalid response code: " + line)
+		return
+	}
+	message = line[4:]
+	if 1 <= expectCode && expectCode < 10 && code/100 != expectCode ||
+		10 <= expectCode && expectCode < 100 && code/10 != expectCode ||
+		100 <= expectCode && expectCode < 1000 && code != expectCode {
+		err = &Error{code, message}
+	}
+	return
+}
+
+// ReadCodeLine reads a response code line of the form
+//
+//	code message
+//
+// where code is a three-digit status code and the message
+// extends to the rest of the line. An example of such a line is:
+//
+//	220 plan9.bell-labs.com ESMTP
+//
+// If the prefix of the status does not match the digits in expectCode,
+// ReadCodeLine returns with err set to &Error{code, message}.
+// For example, if expectCode is 31, an error will be returned if
+// the status is not in the range [310,319].
+//
+// If the response is multi-line, ReadCodeLine returns an error.
+//
+// An expectCode <= 0 disables the check of the status code.
+func (r *Reader) ReadCodeLine(expectCode int) (code int, message string, err error) {
+	code, continued, message, err := r.readCodeLine(expectCode)
+	if err == nil && continued {
+		err = ProtocolError("unexpected multi-line response: " + message)
+	}
+	return
+}
+
+// ReadResponse reads a multi-line response of the form:
+//
+//	code-message line 1
+//	code-message line 2
+//	...
+//	code message line n
+//
+// where code is a three-digit status code. The first line starts with the
+// code and a hyphen. The response is terminated by a line that starts
+// with the same code followed by a space. Each line in message is
+// separated by a newline (\n).
+//
+// See page 36 of RFC 959 (https://www.ietf.org/rfc/rfc959.txt) for
+// details of another form of response accepted:
+//
+//	code-message line 1
+//	message line 2
+//	...
+//	code message line n
+//
+// If the prefix of the status does not match the digits in expectCode,
+// ReadResponse returns with err set to &Error{code, message}.
+// For example, if expectCode is 31, an error will be returned if
+// the status is not in the range [310,319].
+//
+// An expectCode <= 0 disables the check of the status code.
+func (r *Reader) ReadResponse(expectCode int) (code int, message string, err error) {
+	code, continued, message, err := r.readCodeLine(expectCode)
+	multi := continued
+	for continued {
+		line, err := r.ReadLine()
+		if err != nil {
+			return 0, "", err
+		}
+
+		var code2 int
+		var moreMessage string
+		code2, continued, moreMessage, err = parseCodeLine(line, 0)
+		if err != nil || code2 != code {
+			message += "\n" + strings.TrimRight(line, "\r\n")
+			continued = true
+			continue
+		}
+		message += "\n" + moreMessage
+	}
+	if err != nil && multi && message != "" {
+		// replace one line error message with all lines (full message)
+		err = &Error{code, message}
+	}
+	return
+}
+
+// DotReader returns a new Reader that satisfies Reads using the
+// decoded text of a dot-encoded block read from r.
+// The returned Reader is only valid until the next call
+// to a method on r.
+//
+// Dot encoding is a common framing used for data blocks
+// in text protocols such as SMTP.  The data consists of a sequence
+// of lines, each of which ends in "\r\n".  The sequence itself
+// ends at a line containing just a dot: ".\r\n".  Lines beginning
+// with a dot are escaped with an additional dot to avoid
+// looking like the end of the sequence.
+//
+// The decoded form returned by the Reader's Read method
+// rewrites the "\r\n" line endings into the simpler "\n",
+// removes leading dot escapes if present, and stops with error io.EOF
+// after consuming (and discarding) the end-of-sequence line.
+func (r *Reader) DotReader() io.Reader {
+	r.closeDot()
+	r.dot = &dotReader{r: r}
+	return r.dot
+}
+
+type dotReader struct {
+	r     *Reader
+	state int
+}
+
+// Read satisfies reads by decoding dot-encoded data read from d.r.
+func (d *dotReader) Read(b []byte) (n int, err error) {
+	// Run data through a simple state machine to
+	// elide leading dots, rewrite trailing \r\n into \n,
+	// and detect ending .\r\n line.
+	const (
+		stateBeginLine = iota // beginning of line; initial state; must be zero
+		stateDot              // read . at beginning of line
+		stateDotCR            // read .\r at beginning of line
+		stateCR               // read \r (possibly at end of line)
+		stateData             // reading data in middle of line
+		stateEOF              // reached .\r\n end marker line
+	)
+	br := d.r.R
+	for n < len(b) && d.state != stateEOF {
+		var c byte
+		c, err = br.ReadByte()
+		if err != nil {
+			if err == io.EOF {
+				err = io.ErrUnexpectedEOF
+			}
+			break
+		}
+		switch d.state {
+		case stateBeginLine:
+			if c == '.' {
+				d.state = stateDot
+				continue
+			}
+			if c == '\r' {
+				d.state = stateCR
+				continue
+			}
+			d.state = stateData
+
+		case stateDot:
+			if c == '\r' {
+				d.state = stateDotCR
+				continue
+			}
+			if c == '\n' {
+				d.state = stateEOF
+				continue
+			}
+			d.state = stateData
+
+		case stateDotCR:
+			if c == '\n' {
+				d.state = stateEOF
+				continue
+			}
+			// Not part of .\r\n.
+			// Consume leading dot and emit saved \r.
+			br.UnreadByte()
+			c = '\r'
+			d.state = stateData
+
+		case stateCR:
+			if c == '\n' {
+				d.state = stateBeginLine
+				break
+			}
+			// Not part of \r\n. Emit saved \r
+			br.UnreadByte()
+			c = '\r'
+			d.state = stateData
+
+		case stateData:
+			if c == '\r' {
+				d.state = stateCR
+				continue
+			}
+			if c == '\n' {
+				d.state = stateBeginLine
+			}
+		}
+		b[n] = c
+		n++
+	}
+	if err == nil && d.state == stateEOF {
+		err = io.EOF
+	}
+	if err != nil && d.r.dot == d {
+		d.r.dot = nil
+	}
+	return
+}
+
+// closeDot drains the current DotReader if any,
+// making sure that it reads until the ending dot line.
+func (r *Reader) closeDot() {
+	if r.dot == nil {
+		return
+	}
+	buf := make([]byte, 128)
+	for r.dot != nil {
+		// When Read reaches EOF or an error,
+		// it will set r.dot == nil.
+		r.dot.Read(buf)
+	}
+}
+
+// ReadDotBytes reads a dot-encoding and returns the decoded data.
+//
+// See the documentation for the DotReader method for details about dot-encoding.
+func (r *Reader) ReadDotBytes() ([]byte, error) {
+	return io.ReadAll(r.DotReader())
+}
+
+// ReadDotLines reads a dot-encoding and returns a slice
+// containing the decoded lines, with the final \r\n or \n elided from each.
+//
+// See the documentation for the DotReader method for details about dot-encoding.
+func (r *Reader) ReadDotLines() ([]string, error) {
+	// We could use ReadDotBytes and then Split it,
+	// but reading a line at a time avoids needing a
+	// large contiguous block of memory and is simpler.
+	var v []string
+	var err error
+	for {
+		var line string
+		line, err = r.ReadLine()
+		if err != nil {
+			if err == io.EOF {
+				err = io.ErrUnexpectedEOF
+			}
+			break
+		}
+
+		// Dot by itself marks end; otherwise cut one dot.
+		if len(line) > 0 && line[0] == '.' {
+			if len(line) == 1 {
+				break
+			}
+			line = line[1:]
+		}
+		v = append(v, line)
+	}
+	return v, err
+}
+
+var colon = []byte(":")
+
+// ReadMIMEHeader reads a MIME-style header from r.
+// The header is a sequence of possibly continued Key: Value lines
+// ending in a blank line.
+// The returned map m maps CanonicalMIMEHeaderKey(key) to a
+// sequence of values in the same order encountered in the input.
+//
+// For example, consider this input:
+//
+//	My-Key: Value 1
+//	Long-Key: Even
+//	       Longer Value
+//	My-Key: Value 2
+//
+// Given that input, ReadMIMEHeader returns the map:
+//
+//	map[string][]string{
+//		"My-Key": {"Value 1", "Value 2"},
+//		"Long-Key": {"Even Longer Value"},
+//	}
+func (r *Reader) ReadMIMEHeader() (MIMEHeader, error) {
+	// Avoid lots of small slice allocations later by allocating one
+	// large one ahead of time which we'll cut up into smaller
+	// slices. If this isn't big enough later, we allocate small ones.
+	var strs []string
+	hint := r.upcomingHeaderNewlines()
+	if hint > 0 {
+		strs = make([]string, hint)
+	}
+
+	m := make(MIMEHeader, hint)
+
+	// The first line cannot start with a leading space.
+	if buf, err := r.R.Peek(1); err == nil && (buf[0] == ' ' || buf[0] == '\t') {
+		line, err := r.readLineSlice()
+		if err != nil {
+			return m, err
+		}
+		return m, ProtocolError("malformed MIME header initial line: " + string(line))
+	}
+
+	for {
+		kv, err := r.readContinuedLineSlice(mustHaveFieldNameColon)
+		if len(kv) == 0 {
+			return m, err
+		}
+
+		// Key ends at first colon.
+		k, v, ok := bytes.Cut(kv, colon)
+		if !ok {
+			return m, ProtocolError("malformed MIME header line: " + string(kv))
+		}
+		key := canonicalMIMEHeaderKey(k)
+
+		// As per RFC 7230 field-name is a token, tokens consist of one or more chars.
+		// We could return a ProtocolError here, but better to be liberal in what we
+		// accept, so if we get an empty key, skip it.
+		if key == "" {
+			continue
+		}
+
+		// Skip initial spaces in value.
+		value := strings.TrimLeft(string(v), " \t")
+
+		vv := m[key]
+		if vv == nil && len(strs) > 0 {
+			// More than likely this will be a single-element key.
+			// Most headers aren't multi-valued.
+			// Set the capacity on strs[0] to 1, so any future append
+			// won't extend the slice into the other strings.
+			vv, strs = strs[:1:1], strs[1:]
+			vv[0] = value
+			m[key] = vv
+		} else {
+			m[key] = append(vv, value)
+		}
+
+		if err != nil {
+			return m, err
+		}
+	}
+}
+
+// noValidation is a no-op validation func for readContinuedLineSlice
+// that permits any lines.
+func noValidation(_ []byte) error { return nil }
+
+// mustHaveFieldNameColon ensures that, per RFC 7230, the
+// field-name is on a single line, so the first line must
+// contain a colon.
+func mustHaveFieldNameColon(line []byte) error {
+	if bytes.IndexByte(line, ':') < 0 {
+		return ProtocolError(fmt.Sprintf("malformed MIME header: missing colon: %q", line))
+	}
+	return nil
+}
+
+var nl = []byte("\n")
+
+// upcomingHeaderNewlines returns an approximation of the number of newlines
+// that will be in this header. If it gets confused, it returns 0.
+func (r *Reader) upcomingHeaderNewlines() (n int) {
+	// Try to determine the 'hint' size.
+	r.R.Peek(1) // force a buffer load if empty
+	s := r.R.Buffered()
+	if s == 0 {
+		return
+	}
+	peek, _ := r.R.Peek(s)
+	return bytes.Count(peek, nl)
+}
+
+// CanonicalMIMEHeaderKey returns the canonical format of the
+// MIME header key s. The canonicalization converts the first
+// letter and any letter following a hyphen to upper case;
+// the rest are converted to lowercase. For example, the
+// canonical key for "accept-encoding" is "Accept-Encoding".
+// MIME header keys are assumed to be ASCII only.
+// If s contains a space or invalid header field bytes, it is
+// returned without modifications.
+func CanonicalMIMEHeaderKey(s string) string {
+	// Quick check for canonical encoding.
+	upper := true
+	for i := 0; i < len(s); i++ {
+		c := s[i]
+		if !validHeaderFieldByte(c) {
+			return s
+		}
+		if upper && 'a' <= c && c <= 'z' {
+			return canonicalMIMEHeaderKey([]byte(s))
+		}
+		if !upper && 'A' <= c && c <= 'Z' {
+			return canonicalMIMEHeaderKey([]byte(s))
+		}
+		upper = c == '-'
+	}
+	return s
+}
+
+const toLower = 'a' - 'A'
+
+// validHeaderFieldByte reports whether b is a valid byte in a header
+// field name. RFC 7230 says:
+//
+//	header-field   = field-name ":" OWS field-value OWS
+//	field-name     = token
+//	tchar = "!" / "#" / "$" / "%" / "&" / "'" / "*" / "+" / "-" / "." /
+//	        "^" / "_" / "`" / "|" / "~" / DIGIT / ALPHA
+//	token = 1*tchar
+func validHeaderFieldByte(b byte) bool {
+	return int(b) < len(isTokenTable) && isTokenTable[b]
+}
+
+// canonicalMIMEHeaderKey is like CanonicalMIMEHeaderKey but is
+// allowed to mutate the provided byte slice before returning the
+// string.
+//
+// For invalid inputs (if a contains spaces or non-token bytes), a
+// is unchanged and a string copy is returned.
+func canonicalMIMEHeaderKey(a []byte) string {
+	// See if a looks like a header key. If not, return it unchanged.
+	for _, c := range a {
+		if validHeaderFieldByte(c) {
+			continue
+		}
+		// Don't canonicalize.
+		return string(a)
+	}
+
+	upper := true
+	for i, c := range a {
+		// Canonicalize: first letter upper case
+		// and upper case after each dash.
+		// (Host, User-Agent, If-Modified-Since).
+		// MIME headers are ASCII only, so no Unicode issues.
+		if upper && 'a' <= c && c <= 'z' {
+			c -= toLower
+		} else if !upper && 'A' <= c && c <= 'Z' {
+			c += toLower
+		}
+		a[i] = c
+		upper = c == '-' // for next time
+	}
+	commonHeaderOnce.Do(initCommonHeader)
+	// The compiler recognizes m[string(byteSlice)] as a special
+	// case, so a copy of a's bytes into a new string does not
+	// happen in this map lookup:
+	if v := commonHeader[string(a)]; v != "" {
+		return v
+	}
+	return string(a)
+}
+
+// commonHeader interns common header strings.
+var commonHeader map[string]string
+
+var commonHeaderOnce sync.Once
+
+func initCommonHeader() {
+	commonHeader = make(map[string]string)
+	for _, v := range []string{
+		"Accept",
+		"Accept-Charset",
+		"Accept-Encoding",
+		"Accept-Language",
+		"Accept-Ranges",
+		"Cache-Control",
+		"Cc",
+		"Connection",
+		"Content-Id",
+		"Content-Language",
+		"Content-Length",
+		"Content-Transfer-Encoding",
+		"Content-Type",
+		"Cookie",
+		"Date",
+		"Dkim-Signature",
+		"Etag",
+		"Expires",
+		"From",
+		"Host",
+		"If-Modified-Since",
+		"If-None-Match",
+		"In-Reply-To",
+		"Last-Modified",
+		"Location",
+		"Message-Id",
+		"Mime-Version",
+		"Pragma",
+		"Received",
+		"Return-Path",
+		"Server",
+		"Set-Cookie",
+		"Subject",
+		"To",
+		"User-Agent",
+		"Via",
+		"X-Forwarded-For",
+		"X-Imforwards",
+		"X-Powered-By",
+	} {
+		commonHeader[v] = v
+	}
+}
+
+// isTokenTable is a copy of net/http/lex.go's isTokenTable.
+// See https://httpwg.github.io/specs/rfc7230.html#rule.token.separators
+var isTokenTable = [127]bool{
+	'!':  true,
+	'#':  true,
+	'$':  true,
+	'%':  true,
+	'&':  true,
+	'\'': true,
+	'*':  true,
+	'+':  true,
+	'-':  true,
+	'.':  true,
+	'0':  true,
+	'1':  true,
+	'2':  true,
+	'3':  true,
+	'4':  true,
+	'5':  true,
+	'6':  true,
+	'7':  true,
+	'8':  true,
+	'9':  true,
+	'A':  true,
+	'B':  true,
+	'C':  true,
+	'D':  true,
+	'E':  true,
+	'F':  true,
+	'G':  true,
+	'H':  true,
+	'I':  true,
+	'J':  true,
+	'K':  true,
+	'L':  true,
+	'M':  true,
+	'N':  true,
+	'O':  true,
+	'P':  true,
+	'Q':  true,
+	'R':  true,
+	'S':  true,
+	'T':  true,
+	'U':  true,
+	'W':  true,
+	'V':  true,
+	'X':  true,
+	'Y':  true,
+	'Z':  true,
+	'^':  true,
+	'_':  true,
+	'`':  true,
+	'a':  true,
+	'b':  true,
+	'c':  true,
+	'd':  true,
+	'e':  true,
+	'f':  true,
+	'g':  true,
+	'h':  true,
+	'i':  true,
+	'j':  true,
+	'k':  true,
+	'l':  true,
+	'm':  true,
+	'n':  true,
+	'o':  true,
+	'p':  true,
+	'q':  true,
+	'r':  true,
+	's':  true,
+	't':  true,
+	'u':  true,
+	'v':  true,
+	'w':  true,
+	'x':  true,
+	'y':  true,
+	'z':  true,
+	'|':  true,
+	'~':  true,
+}
diff --git a/contrib/go/_std_1.19/src/net/textproto/textproto.go b/contrib/go/_std_1.19/src/net/textproto/textproto.go
new file mode 100644
index 0000000000..70038d5888
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/textproto/textproto.go
@@ -0,0 +1,152 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package textproto implements generic support for text-based request/response
+// protocols in the style of HTTP, NNTP, and SMTP.
+//
+// The package provides:
+//
+// Error, which represents a numeric error response from
+// a server.
+//
+// Pipeline, to manage pipelined requests and responses
+// in a client.
+//
+// Reader, to read numeric response code lines,
+// key: value headers, lines wrapped with leading spaces
+// on continuation lines, and whole text blocks ending
+// with a dot on a line by itself.
+//
+// Writer, to write dot-encoded text blocks.
+//
+// Conn, a convenient packaging of Reader, Writer, and Pipeline for use
+// with a single network connection.
+package textproto
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"net"
+)
+
+// An Error represents a numeric error response from a server.
+type Error struct {
+	Code int
+	Msg  string
+}
+
+func (e *Error) Error() string {
+	return fmt.Sprintf("%03d %s", e.Code, e.Msg)
+}
+
+// A ProtocolError describes a protocol violation such
+// as an invalid response or a hung-up connection.
+type ProtocolError string
+
+func (p ProtocolError) Error() string {
+	return string(p)
+}
+
+// A Conn represents a textual network protocol connection.
+// It consists of a Reader and Writer to manage I/O
+// and a Pipeline to sequence concurrent requests on the connection.
+// These embedded types carry methods with them;
+// see the documentation of those types for details.
+type Conn struct {
+	Reader
+	Writer
+	Pipeline
+	conn io.ReadWriteCloser
+}
+
+// NewConn returns a new Conn using conn for I/O.
+func NewConn(conn io.ReadWriteCloser) *Conn {
+	return &Conn{
+		Reader: Reader{R: bufio.NewReader(conn)},
+		Writer: Writer{W: bufio.NewWriter(conn)},
+		conn:   conn,
+	}
+}
+
+// Close closes the connection.
+func (c *Conn) Close() error {
+	return c.conn.Close()
+}
+
+// Dial connects to the given address on the given network using net.Dial
+// and then returns a new Conn for the connection.
+func Dial(network, addr string) (*Conn, error) {
+	c, err := net.Dial(network, addr)
+	if err != nil {
+		return nil, err
+	}
+	return NewConn(c), nil
+}
+
+// Cmd is a convenience method that sends a command after
+// waiting its turn in the pipeline. The command text is the
+// result of formatting format with args and appending \r\n.
+// Cmd returns the id of the command, for use with StartResponse and EndResponse.
+//
+// For example, a client might run a HELP command that returns a dot-body
+// by using:
+//
+//	id, err := c.Cmd("HELP")
+//	if err != nil {
+//		return nil, err
+//	}
+//
+//	c.StartResponse(id)
+//	defer c.EndResponse(id)
+//
+//	if _, _, err = c.ReadCodeLine(110); err != nil {
+//		return nil, err
+//	}
+//	text, err := c.ReadDotBytes()
+//	if err != nil {
+//		return nil, err
+//	}
+//	return c.ReadCodeLine(250)
+func (c *Conn) Cmd(format string, args ...any) (id uint, err error) {
+	id = c.Next()
+	c.StartRequest(id)
+	err = c.PrintfLine(format, args...)
+	c.EndRequest(id)
+	if err != nil {
+		return 0, err
+	}
+	return id, nil
+}
+
+// TrimString returns s without leading and trailing ASCII space.
+func TrimString(s string) string {
+	for len(s) > 0 && isASCIISpace(s[0]) {
+		s = s[1:]
+	}
+	for len(s) > 0 && isASCIISpace(s[len(s)-1]) {
+		s = s[:len(s)-1]
+	}
+	return s
+}
+
+// TrimBytes returns b without leading and trailing ASCII space.
+func TrimBytes(b []byte) []byte {
+	for len(b) > 0 && isASCIISpace(b[0]) {
+		b = b[1:]
+	}
+	for len(b) > 0 && isASCIISpace(b[len(b)-1]) {
+		b = b[:len(b)-1]
+	}
+	return b
+}
+
+func isASCIISpace(b byte) bool {
+	return b == ' ' || b == '\t' || b == '\n' || b == '\r'
+}
+
+func isASCIILetter(b byte) bool {
+	b |= 0x20 // make lower case
+	return 'a' <= b && b <= 'z'
+}
diff --git a/contrib/go/_std_1.18/src/net/textproto/writer.go b/contrib/go/_std_1.19/src/net/textproto/writer.go
index 2ece3f511b..2ece3f511b 100644
--- a/contrib/go/_std_1.18/src/net/textproto/writer.go
+++ b/contrib/go/_std_1.19/src/net/textproto/writer.go
diff --git a/contrib/go/_std_1.19/src/net/udpsock.go b/contrib/go/_std_1.19/src/net/udpsock.go
new file mode 100644
index 0000000000..e30624dea5
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/udpsock.go
@@ -0,0 +1,368 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+	"context"
+	"internal/itoa"
+	"net/netip"
+	"syscall"
+)
+
+// BUG(mikio): On Plan 9, the ReadMsgUDP and
+// WriteMsgUDP methods of UDPConn are not implemented.
+
+// BUG(mikio): On Windows, the File method of UDPConn is not
+// implemented.
+
+// BUG(mikio): On JS, methods and functions related to UDPConn are not
+// implemented.
+
+// UDPAddr represents the address of a UDP end point.
+type UDPAddr struct {
+	IP   IP
+	Port int
+	Zone string // IPv6 scoped addressing zone
+}
+
+// AddrPort returns the UDPAddr a as a netip.AddrPort.
+//
+// If a.Port does not fit in a uint16, it's silently truncated.
+//
+// If a is nil, a zero value is returned.
+func (a *UDPAddr) AddrPort() netip.AddrPort {
+	if a == nil {
+		return netip.AddrPort{}
+	}
+	na, _ := netip.AddrFromSlice(a.IP)
+	na = na.WithZone(a.Zone)
+	return netip.AddrPortFrom(na, uint16(a.Port))
+}
+
+// Network returns the address's network name, "udp".
+func (a *UDPAddr) Network() string { return "udp" }
+
+func (a *UDPAddr) String() string {
+	if a == nil {
+		return "<nil>"
+	}
+	ip := ipEmptyString(a.IP)
+	if a.Zone != "" {
+		return JoinHostPort(ip+"%"+a.Zone, itoa.Itoa(a.Port))
+	}
+	return JoinHostPort(ip, itoa.Itoa(a.Port))
+}
+
+func (a *UDPAddr) isWildcard() bool {
+	if a == nil || a.IP == nil {
+		return true
+	}
+	return a.IP.IsUnspecified()
+}
+
+func (a *UDPAddr) opAddr() Addr {
+	if a == nil {
+		return nil
+	}
+	return a
+}
+
+// ResolveUDPAddr returns an address of UDP end point.
+//
+// The network must be a UDP network name.
+//
+// If the host in the address parameter is not a literal IP address or
+// the port is not a literal port number, ResolveUDPAddr resolves the
+// address to an address of UDP end point.
+// Otherwise, it parses the address as a pair of literal IP address
+// and port number.
+// The address parameter can use a host name, but this is not
+// recommended, because it will return at most one of the host name's
+// IP addresses.
+//
+// See func Dial for a description of the network and address
+// parameters.
+func ResolveUDPAddr(network, address string) (*UDPAddr, error) {
+	switch network {
+	case "udp", "udp4", "udp6":
+	case "": // a hint wildcard for Go 1.0 undocumented behavior
+		network = "udp"
+	default:
+		return nil, UnknownNetworkError(network)
+	}
+	addrs, err := DefaultResolver.internetAddrList(context.Background(), network, address)
+	if err != nil {
+		return nil, err
+	}
+	return addrs.forResolve(network, address).(*UDPAddr), nil
+}
+
+// UDPAddrFromAddrPort returns addr as a UDPAddr. If addr.IsValid() is false,
+// then the returned UDPAddr will contain a nil IP field, indicating an
+// address family-agnostic unspecified address.
+func UDPAddrFromAddrPort(addr netip.AddrPort) *UDPAddr {
+	return &UDPAddr{
+		IP:   addr.Addr().AsSlice(),
+		Zone: addr.Addr().Zone(),
+		Port: int(addr.Port()),
+	}
+}
+
+// An addrPortUDPAddr is a netip.AddrPort-based UDP address that satisfies the Addr interface.
+type addrPortUDPAddr struct {
+	netip.AddrPort
+}
+
+func (addrPortUDPAddr) Network() string { return "udp" }
+
+// UDPConn is the implementation of the Conn and PacketConn interfaces
+// for UDP network connections.
+type UDPConn struct {
+	conn
+}
+
+// SyscallConn returns a raw network connection.
+// This implements the syscall.Conn interface.
+func (c *UDPConn) SyscallConn() (syscall.RawConn, error) {
+	if !c.ok() {
+		return nil, syscall.EINVAL
+	}
+	return newRawConn(c.fd)
+}
+
+// ReadFromUDP acts like ReadFrom but returns a UDPAddr.
+func (c *UDPConn) ReadFromUDP(b []byte) (n int, addr *UDPAddr, err error) {
+	// This function is designed to allow the caller to control the lifetime
+	// of the returned *UDPAddr and thereby prevent an allocation.
+	// See https://blog.filippo.io/efficient-go-apis-with-the-inliner/.
+	// The real work is done by readFromUDP, below.
+	return c.readFromUDP(b, &UDPAddr{})
+}
+
+// readFromUDP implements ReadFromUDP.
+func (c *UDPConn) readFromUDP(b []byte, addr *UDPAddr) (int, *UDPAddr, error) {
+	if !c.ok() {
+		return 0, nil, syscall.EINVAL
+	}
+	n, addr, err := c.readFrom(b, addr)
+	if err != nil {
+		err = &OpError{Op: "read", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+	}
+	return n, addr, err
+}
+
+// ReadFrom implements the PacketConn ReadFrom method.
+func (c *UDPConn) ReadFrom(b []byte) (int, Addr, error) {
+	n, addr, err := c.readFromUDP(b, &UDPAddr{})
+	if addr == nil {
+		// Return Addr(nil), not Addr(*UDPConn(nil)).
+		return n, nil, err
+	}
+	return n, addr, err
+}
+
+// ReadFromUDPAddrPort acts like ReadFrom but returns a netip.AddrPort.
+//
+// If c is bound to an unspecified address, the returned
+// netip.AddrPort's address might be an IPv4-mapped IPv6 address.
+// Use netip.Addr.Unmap to get the address without the IPv6 prefix.
+func (c *UDPConn) ReadFromUDPAddrPort(b []byte) (n int, addr netip.AddrPort, err error) {
+	if !c.ok() {
+		return 0, netip.AddrPort{}, syscall.EINVAL
+	}
+	n, addr, err = c.readFromAddrPort(b)
+	if err != nil {
+		err = &OpError{Op: "read", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+	}
+	return n, addr, err
+}
+
+// ReadMsgUDP reads a message from c, copying the payload into b and
+// the associated out-of-band data into oob. It returns the number of
+// bytes copied into b, the number of bytes copied into oob, the flags
+// that were set on the message and the source address of the message.
+//
+// The packages golang.org/x/net/ipv4 and golang.org/x/net/ipv6 can be
+// used to manipulate IP-level socket options in oob.
+func (c *UDPConn) ReadMsgUDP(b, oob []byte) (n, oobn, flags int, addr *UDPAddr, err error) {
+	var ap netip.AddrPort
+	n, oobn, flags, ap, err = c.ReadMsgUDPAddrPort(b, oob)
+	if ap.IsValid() {
+		addr = UDPAddrFromAddrPort(ap)
+	}
+	return
+}
+
+// ReadMsgUDPAddrPort is like ReadMsgUDP but returns an netip.AddrPort instead of a UDPAddr.
+func (c *UDPConn) ReadMsgUDPAddrPort(b, oob []byte) (n, oobn, flags int, addr netip.AddrPort, err error) {
+	if !c.ok() {
+		return 0, 0, 0, netip.AddrPort{}, syscall.EINVAL
+	}
+	n, oobn, flags, addr, err = c.readMsg(b, oob)
+	if err != nil {
+		err = &OpError{Op: "read", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+	}
+	return
+}
+
+// WriteToUDP acts like WriteTo but takes a UDPAddr.
+func (c *UDPConn) WriteToUDP(b []byte, addr *UDPAddr) (int, error) {
+	if !c.ok() {
+		return 0, syscall.EINVAL
+	}
+	n, err := c.writeTo(b, addr)
+	if err != nil {
+		err = &OpError{Op: "write", Net: c.fd.net, Source: c.fd.laddr, Addr: addr.opAddr(), Err: err}
+	}
+	return n, err
+}
+
+// WriteToUDPAddrPort acts like WriteTo but takes a netip.AddrPort.
+func (c *UDPConn) WriteToUDPAddrPort(b []byte, addr netip.AddrPort) (int, error) {
+	if !c.ok() {
+		return 0, syscall.EINVAL
+	}
+	n, err := c.writeToAddrPort(b, addr)
+	if err != nil {
+		err = &OpError{Op: "write", Net: c.fd.net, Source: c.fd.laddr, Addr: addrPortUDPAddr{addr}, Err: err}
+	}
+	return n, err
+}
+
+// WriteTo implements the PacketConn WriteTo method.
+func (c *UDPConn) WriteTo(b []byte, addr Addr) (int, error) {
+	if !c.ok() {
+		return 0, syscall.EINVAL
+	}
+	a, ok := addr.(*UDPAddr)
+	if !ok {
+		return 0, &OpError{Op: "write", Net: c.fd.net, Source: c.fd.laddr, Addr: addr, Err: syscall.EINVAL}
+	}
+	n, err := c.writeTo(b, a)
+	if err != nil {
+		err = &OpError{Op: "write", Net: c.fd.net, Source: c.fd.laddr, Addr: a.opAddr(), Err: err}
+	}
+	return n, err
+}
+
+// WriteMsgUDP writes a message to addr via c if c isn't connected, or
+// to c's remote address if c is connected (in which case addr must be
+// nil). The payload is copied from b and the associated out-of-band
+// data is copied from oob. It returns the number of payload and
+// out-of-band bytes written.
+//
+// The packages golang.org/x/net/ipv4 and golang.org/x/net/ipv6 can be
+// used to manipulate IP-level socket options in oob.
+func (c *UDPConn) WriteMsgUDP(b, oob []byte, addr *UDPAddr) (n, oobn int, err error) {
+	if !c.ok() {
+		return 0, 0, syscall.EINVAL
+	}
+	n, oobn, err = c.writeMsg(b, oob, addr)
+	if err != nil {
+		err = &OpError{Op: "write", Net: c.fd.net, Source: c.fd.laddr, Addr: addr.opAddr(), Err: err}
+	}
+	return
+}
+
+// WriteMsgUDPAddrPort is like WriteMsgUDP but takes a netip.AddrPort instead of a UDPAddr.
+func (c *UDPConn) WriteMsgUDPAddrPort(b, oob []byte, addr netip.AddrPort) (n, oobn int, err error) {
+	if !c.ok() {
+		return 0, 0, syscall.EINVAL
+	}
+	n, oobn, err = c.writeMsgAddrPort(b, oob, addr)
+	if err != nil {
+		err = &OpError{Op: "write", Net: c.fd.net, Source: c.fd.laddr, Addr: addrPortUDPAddr{addr}, Err: err}
+	}
+	return
+}
+
+func newUDPConn(fd *netFD) *UDPConn { return &UDPConn{conn{fd}} }
+
+// DialUDP acts like Dial for UDP networks.
+//
+// The network must be a UDP network name; see func Dial for details.
+//
+// If laddr is nil, a local address is automatically chosen.
+// If the IP field of raddr is nil or an unspecified IP address, the
+// local system is assumed.
+func DialUDP(network string, laddr, raddr *UDPAddr) (*UDPConn, error) {
+	switch network {
+	case "udp", "udp4", "udp6":
+	default:
+		return nil, &OpError{Op: "dial", Net: network, Source: laddr.opAddr(), Addr: raddr.opAddr(), Err: UnknownNetworkError(network)}
+	}
+	if raddr == nil {
+		return nil, &OpError{Op: "dial", Net: network, Source: laddr.opAddr(), Addr: nil, Err: errMissingAddress}
+	}
+	sd := &sysDialer{network: network, address: raddr.String()}
+	c, err := sd.dialUDP(context.Background(), laddr, raddr)
+	if err != nil {
+		return nil, &OpError{Op: "dial", Net: network, Source: laddr.opAddr(), Addr: raddr.opAddr(), Err: err}
+	}
+	return c, nil
+}
+
+// ListenUDP acts like ListenPacket for UDP networks.
+//
+// The network must be a UDP network name; see func Dial for details.
+//
+// If the IP field of laddr is nil or an unspecified IP address,
+// ListenUDP listens on all available IP addresses of the local system
+// except multicast IP addresses.
+// If the Port field of laddr is 0, a port number is automatically
+// chosen.
+func ListenUDP(network string, laddr *UDPAddr) (*UDPConn, error) {
+	switch network {
+	case "udp", "udp4", "udp6":
+	default:
+		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: laddr.opAddr(), Err: UnknownNetworkError(network)}
+	}
+	if laddr == nil {
+		laddr = &UDPAddr{}
+	}
+	sl := &sysListener{network: network, address: laddr.String()}
+	c, err := sl.listenUDP(context.Background(), laddr)
+	if err != nil {
+		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: laddr.opAddr(), Err: err}
+	}
+	return c, nil
+}
+
+// ListenMulticastUDP acts like ListenPacket for UDP networks but
+// takes a group address on a specific network interface.
+//
+// The network must be a UDP network name; see func Dial for details.
+//
+// ListenMulticastUDP listens on all available IP addresses of the
+// local system including the group, multicast IP address.
+// If ifi is nil, ListenMulticastUDP uses the system-assigned
+// multicast interface, although this is not recommended because the
+// assignment depends on platforms and sometimes it might require
+// routing configuration.
+// If the Port field of gaddr is 0, a port number is automatically
+// chosen.
+//
+// ListenMulticastUDP is just for convenience of simple, small
+// applications. There are golang.org/x/net/ipv4 and
+// golang.org/x/net/ipv6 packages for general purpose uses.
+//
+// Note that ListenMulticastUDP will set the IP_MULTICAST_LOOP socket option
+// to 0 under IPPROTO_IP, to disable loopback of multicast packets.
+func ListenMulticastUDP(network string, ifi *Interface, gaddr *UDPAddr) (*UDPConn, error) {
+	switch network {
+	case "udp", "udp4", "udp6":
+	default:
+		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: gaddr.opAddr(), Err: UnknownNetworkError(network)}
+	}
+	if gaddr == nil || gaddr.IP == nil {
+		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: gaddr.opAddr(), Err: errMissingAddress}
+	}
+	sl := &sysListener{network: network, address: gaddr.String()}
+	c, err := sl.listenMulticastUDP(context.Background(), ifi, gaddr)
+	if err != nil {
+		return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: gaddr.opAddr(), Err: err}
+	}
+	return c, nil
+}
diff --git a/contrib/go/_std_1.19/src/net/udpsock_posix.go b/contrib/go/_std_1.19/src/net/udpsock_posix.go
new file mode 100644
index 0000000000..5b021d24ae
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/udpsock_posix.go
@@ -0,0 +1,269 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm) || windows
+
+package net
+
+import (
+	"context"
+	"net/netip"
+	"syscall"
+)
+
+func sockaddrToUDP(sa syscall.Sockaddr) Addr {
+	switch sa := sa.(type) {
+	case *syscall.SockaddrInet4:
+		return &UDPAddr{IP: sa.Addr[0:], Port: sa.Port}
+	case *syscall.SockaddrInet6:
+		return &UDPAddr{IP: sa.Addr[0:], Port: sa.Port, Zone: zoneCache.name(int(sa.ZoneId))}
+	}
+	return nil
+}
+
+func (a *UDPAddr) family() int {
+	if a == nil || len(a.IP) <= IPv4len {
+		return syscall.AF_INET
+	}
+	if a.IP.To4() != nil {
+		return syscall.AF_INET
+	}
+	return syscall.AF_INET6
+}
+
+func (a *UDPAddr) sockaddr(family int) (syscall.Sockaddr, error) {
+	if a == nil {
+		return nil, nil
+	}
+	return ipToSockaddr(family, a.IP, a.Port, a.Zone)
+}
+
+func (a *UDPAddr) toLocal(net string) sockaddr {
+	return &UDPAddr{loopbackIP(net), a.Port, a.Zone}
+}
+
+func (c *UDPConn) readFrom(b []byte, addr *UDPAddr) (int, *UDPAddr, error) {
+	var n int
+	var err error
+	switch c.fd.family {
+	case syscall.AF_INET:
+		var from syscall.SockaddrInet4
+		n, err = c.fd.readFromInet4(b, &from)
+		if err == nil {
+			ip := from.Addr // copy from.Addr; ip escapes, so this line allocates 4 bytes
+			*addr = UDPAddr{IP: ip[:], Port: from.Port}
+		}
+	case syscall.AF_INET6:
+		var from syscall.SockaddrInet6
+		n, err = c.fd.readFromInet6(b, &from)
+		if err == nil {
+			ip := from.Addr // copy from.Addr; ip escapes, so this line allocates 16 bytes
+			*addr = UDPAddr{IP: ip[:], Port: from.Port, Zone: zoneCache.name(int(from.ZoneId))}
+		}
+	}
+	if err != nil {
+		// No sockaddr, so don't return UDPAddr.
+		addr = nil
+	}
+	return n, addr, err
+}
+
+func (c *UDPConn) readFromAddrPort(b []byte) (n int, addr netip.AddrPort, err error) {
+	var ip netip.Addr
+	var port int
+	switch c.fd.family {
+	case syscall.AF_INET:
+		var from syscall.SockaddrInet4
+		n, err = c.fd.readFromInet4(b, &from)
+		if err == nil {
+			ip = netip.AddrFrom4(from.Addr)
+			port = from.Port
+		}
+	case syscall.AF_INET6:
+		var from syscall.SockaddrInet6
+		n, err = c.fd.readFromInet6(b, &from)
+		if err == nil {
+			ip = netip.AddrFrom16(from.Addr).WithZone(zoneCache.name(int(from.ZoneId)))
+			port = from.Port
+		}
+	}
+	if err == nil {
+		addr = netip.AddrPortFrom(ip, uint16(port))
+	}
+	return n, addr, err
+}
+
+func (c *UDPConn) readMsg(b, oob []byte) (n, oobn, flags int, addr netip.AddrPort, err error) {
+	switch c.fd.family {
+	case syscall.AF_INET:
+		var sa syscall.SockaddrInet4
+		n, oobn, flags, err = c.fd.readMsgInet4(b, oob, 0, &sa)
+		ip := netip.AddrFrom4(sa.Addr)
+		addr = netip.AddrPortFrom(ip, uint16(sa.Port))
+	case syscall.AF_INET6:
+		var sa syscall.SockaddrInet6
+		n, oobn, flags, err = c.fd.readMsgInet6(b, oob, 0, &sa)
+		ip := netip.AddrFrom16(sa.Addr).WithZone(zoneCache.name(int(sa.ZoneId)))
+		addr = netip.AddrPortFrom(ip, uint16(sa.Port))
+	}
+	return
+}
+
+func (c *UDPConn) writeTo(b []byte, addr *UDPAddr) (int, error) {
+	if c.fd.isConnected {
+		return 0, ErrWriteToConnected
+	}
+	if addr == nil {
+		return 0, errMissingAddress
+	}
+
+	switch c.fd.family {
+	case syscall.AF_INET:
+		sa, err := ipToSockaddrInet4(addr.IP, addr.Port)
+		if err != nil {
+			return 0, err
+		}
+		return c.fd.writeToInet4(b, &sa)
+	case syscall.AF_INET6:
+		sa, err := ipToSockaddrInet6(addr.IP, addr.Port, addr.Zone)
+		if err != nil {
+			return 0, err
+		}
+		return c.fd.writeToInet6(b, &sa)
+	default:
+		return 0, &AddrError{Err: "invalid address family", Addr: addr.IP.String()}
+	}
+}
+
+func (c *UDPConn) writeToAddrPort(b []byte, addr netip.AddrPort) (int, error) {
+	if c.fd.isConnected {
+		return 0, ErrWriteToConnected
+	}
+	if !addr.IsValid() {
+		return 0, errMissingAddress
+	}
+
+	switch c.fd.family {
+	case syscall.AF_INET:
+		sa, err := addrPortToSockaddrInet4(addr)
+		if err != nil {
+			return 0, err
+		}
+		return c.fd.writeToInet4(b, &sa)
+	case syscall.AF_INET6:
+		sa, err := addrPortToSockaddrInet6(addr)
+		if err != nil {
+			return 0, err
+		}
+		return c.fd.writeToInet6(b, &sa)
+	default:
+		return 0, &AddrError{Err: "invalid address family", Addr: addr.Addr().String()}
+	}
+}
+
+func (c *UDPConn) writeMsg(b, oob []byte, addr *UDPAddr) (n, oobn int, err error) {
+	if c.fd.isConnected && addr != nil {
+		return 0, 0, ErrWriteToConnected
+	}
+	if !c.fd.isConnected && addr == nil {
+		return 0, 0, errMissingAddress
+	}
+	sa, err := addr.sockaddr(c.fd.family)
+	if err != nil {
+		return 0, 0, err
+	}
+	return c.fd.writeMsg(b, oob, sa)
+}
+
+func (c *UDPConn) writeMsgAddrPort(b, oob []byte, addr netip.AddrPort) (n, oobn int, err error) {
+	if c.fd.isConnected && addr.IsValid() {
+		return 0, 0, ErrWriteToConnected
+	}
+	if !c.fd.isConnected && !addr.IsValid() {
+		return 0, 0, errMissingAddress
+	}
+
+	switch c.fd.family {
+	case syscall.AF_INET:
+		sa, err := addrPortToSockaddrInet4(addr)
+		if err != nil {
+			return 0, 0, err
+		}
+		return c.fd.writeMsgInet4(b, oob, &sa)
+	case syscall.AF_INET6:
+		sa, err := addrPortToSockaddrInet6(addr)
+		if err != nil {
+			return 0, 0, err
+		}
+		return c.fd.writeMsgInet6(b, oob, &sa)
+	default:
+		return 0, 0, &AddrError{Err: "invalid address family", Addr: addr.Addr().String()}
+	}
+}
+
+func (sd *sysDialer) dialUDP(ctx context.Context, laddr, raddr *UDPAddr) (*UDPConn, error) {
+	fd, err := internetSocket(ctx, sd.network, laddr, raddr, syscall.SOCK_DGRAM, 0, "dial", sd.Dialer.Control)
+	if err != nil {
+		return nil, err
+	}
+	return newUDPConn(fd), nil
+}
+
+func (sl *sysListener) listenUDP(ctx context.Context, laddr *UDPAddr) (*UDPConn, error) {
+	fd, err := internetSocket(ctx, sl.network, laddr, nil, syscall.SOCK_DGRAM, 0, "listen", sl.ListenConfig.Control)
+	if err != nil {
+		return nil, err
+	}
+	return newUDPConn(fd), nil
+}
+
+func (sl *sysListener) listenMulticastUDP(ctx context.Context, ifi *Interface, gaddr *UDPAddr) (*UDPConn, error) {
+	fd, err := internetSocket(ctx, sl.network, gaddr, nil, syscall.SOCK_DGRAM, 0, "listen", sl.ListenConfig.Control)
+	if err != nil {
+		return nil, err
+	}
+	c := newUDPConn(fd)
+	if ip4 := gaddr.IP.To4(); ip4 != nil {
+		if err := listenIPv4MulticastUDP(c, ifi, ip4); err != nil {
+			c.Close()
+			return nil, err
+		}
+	} else {
+		if err := listenIPv6MulticastUDP(c, ifi, gaddr.IP); err != nil {
+			c.Close()
+			return nil, err
+		}
+	}
+	return c, nil
+}
+
+func listenIPv4MulticastUDP(c *UDPConn, ifi *Interface, ip IP) error {
+	if ifi != nil {
+		if err := setIPv4MulticastInterface(c.fd, ifi); err != nil {
+			return err
+		}
+	}
+	if err := setIPv4MulticastLoopback(c.fd, false); err != nil {
+		return err
+	}
+	if err := joinIPv4Group(c.fd, ifi, ip); err != nil {
+		return err
+	}
+	return nil
+}
+
+func listenIPv6MulticastUDP(c *UDPConn, ifi *Interface, ip IP) error {
+	if ifi != nil {
+		if err := setIPv6MulticastInterface(c.fd, ifi); err != nil {
+			return err
+		}
+	}
+	if err := setIPv6MulticastLoopback(c.fd, false); err != nil {
+		return err
+	}
+	if err := joinIPv6Group(c.fd, ifi, ip); err != nil {
+		return err
+	}
+	return nil
+}
diff --git a/contrib/go/_std_1.18/src/net/unixsock.go b/contrib/go/_std_1.19/src/net/unixsock.go
index b38438c11a..b38438c11a 100644
--- a/contrib/go/_std_1.18/src/net/unixsock.go
+++ b/contrib/go/_std_1.19/src/net/unixsock.go
diff --git a/contrib/go/_std_1.19/src/net/unixsock_posix.go b/contrib/go/_std_1.19/src/net/unixsock_posix.go
new file mode 100644
index 0000000000..b244dbdbbd
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/unixsock_posix.go
@@ -0,0 +1,227 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm) || windows
+
+package net
+
+import (
+	"context"
+	"errors"
+	"os"
+	"syscall"
+)
+
+func unixSocket(ctx context.Context, net string, laddr, raddr sockaddr, mode string, ctrlFn func(string, string, syscall.RawConn) error) (*netFD, error) {
+	var sotype int
+	switch net {
+	case "unix":
+		sotype = syscall.SOCK_STREAM
+	case "unixgram":
+		sotype = syscall.SOCK_DGRAM
+	case "unixpacket":
+		sotype = syscall.SOCK_SEQPACKET
+	default:
+		return nil, UnknownNetworkError(net)
+	}
+
+	switch mode {
+	case "dial":
+		if laddr != nil && laddr.isWildcard() {
+			laddr = nil
+		}
+		if raddr != nil && raddr.isWildcard() {
+			raddr = nil
+		}
+		if raddr == nil && (sotype != syscall.SOCK_DGRAM || laddr == nil) {
+			return nil, errMissingAddress
+		}
+	case "listen":
+	default:
+		return nil, errors.New("unknown mode: " + mode)
+	}
+
+	fd, err := socket(ctx, net, syscall.AF_UNIX, sotype, 0, false, laddr, raddr, ctrlFn)
+	if err != nil {
+		return nil, err
+	}
+	return fd, nil
+}
+
+func sockaddrToUnix(sa syscall.Sockaddr) Addr {
+	if s, ok := sa.(*syscall.SockaddrUnix); ok {
+		return &UnixAddr{Name: s.Name, Net: "unix"}
+	}
+	return nil
+}
+
+func sockaddrToUnixgram(sa syscall.Sockaddr) Addr {
+	if s, ok := sa.(*syscall.SockaddrUnix); ok {
+		return &UnixAddr{Name: s.Name, Net: "unixgram"}
+	}
+	return nil
+}
+
+func sockaddrToUnixpacket(sa syscall.Sockaddr) Addr {
+	if s, ok := sa.(*syscall.SockaddrUnix); ok {
+		return &UnixAddr{Name: s.Name, Net: "unixpacket"}
+	}
+	return nil
+}
+
+func sotypeToNet(sotype int) string {
+	switch sotype {
+	case syscall.SOCK_STREAM:
+		return "unix"
+	case syscall.SOCK_DGRAM:
+		return "unixgram"
+	case syscall.SOCK_SEQPACKET:
+		return "unixpacket"
+	default:
+		panic("sotypeToNet unknown socket type")
+	}
+}
+
+func (a *UnixAddr) family() int {
+	return syscall.AF_UNIX
+}
+
+func (a *UnixAddr) sockaddr(family int) (syscall.Sockaddr, error) {
+	if a == nil {
+		return nil, nil
+	}
+	return &syscall.SockaddrUnix{Name: a.Name}, nil
+}
+
+func (a *UnixAddr) toLocal(net string) sockaddr {
+	return a
+}
+
+func (c *UnixConn) readFrom(b []byte) (int, *UnixAddr, error) {
+	var addr *UnixAddr
+	n, sa, err := c.fd.readFrom(b)
+	switch sa := sa.(type) {
+	case *syscall.SockaddrUnix:
+		if sa.Name != "" {
+			addr = &UnixAddr{Name: sa.Name, Net: sotypeToNet(c.fd.sotype)}
+		}
+	}
+	return n, addr, err
+}
+
+func (c *UnixConn) readMsg(b, oob []byte) (n, oobn, flags int, addr *UnixAddr, err error) {
+	var sa syscall.Sockaddr
+	n, oobn, flags, sa, err = c.fd.readMsg(b, oob, readMsgFlags)
+	if readMsgFlags == 0 && err == nil && oobn > 0 {
+		setReadMsgCloseOnExec(oob[:oobn])
+	}
+
+	switch sa := sa.(type) {
+	case *syscall.SockaddrUnix:
+		if sa.Name != "" {
+			addr = &UnixAddr{Name: sa.Name, Net: sotypeToNet(c.fd.sotype)}
+		}
+	}
+	return
+}
+
+func (c *UnixConn) writeTo(b []byte, addr *UnixAddr) (int, error) {
+	if c.fd.isConnected {
+		return 0, ErrWriteToConnected
+	}
+	if addr == nil {
+		return 0, errMissingAddress
+	}
+	if addr.Net != sotypeToNet(c.fd.sotype) {
+		return 0, syscall.EAFNOSUPPORT
+	}
+	sa := &syscall.SockaddrUnix{Name: addr.Name}
+	return c.fd.writeTo(b, sa)
+}
+
+func (c *UnixConn) writeMsg(b, oob []byte, addr *UnixAddr) (n, oobn int, err error) {
+	if c.fd.sotype == syscall.SOCK_DGRAM && c.fd.isConnected {
+		return 0, 0, ErrWriteToConnected
+	}
+	var sa syscall.Sockaddr
+	if addr != nil {
+		if addr.Net != sotypeToNet(c.fd.sotype) {
+			return 0, 0, syscall.EAFNOSUPPORT
+		}
+		sa = &syscall.SockaddrUnix{Name: addr.Name}
+	}
+	return c.fd.writeMsg(b, oob, sa)
+}
+
+func (sd *sysDialer) dialUnix(ctx context.Context, laddr, raddr *UnixAddr) (*UnixConn, error) {
+	fd, err := unixSocket(ctx, sd.network, laddr, raddr, "dial", sd.Dialer.Control)
+	if err != nil {
+		return nil, err
+	}
+	return newUnixConn(fd), nil
+}
+
+func (ln *UnixListener) accept() (*UnixConn, error) {
+	fd, err := ln.fd.accept()
+	if err != nil {
+		return nil, err
+	}
+	return newUnixConn(fd), nil
+}
+
+func (ln *UnixListener) close() error {
+	// The operating system doesn't clean up
+	// the file that announcing created, so
+	// we have to clean it up ourselves.
+	// There's a race here--we can't know for
+	// sure whether someone else has come along
+	// and replaced our socket name already--
+	// but this sequence (remove then close)
+	// is at least compatible with the auto-remove
+	// sequence in ListenUnix. It's only non-Go
+	// programs that can mess us up.
+	// Even if there are racy calls to Close, we want to unlink only for the first one.
+	ln.unlinkOnce.Do(func() {
+		if ln.path[0] != '@' && ln.unlink {
+			syscall.Unlink(ln.path)
+		}
+	})
+	return ln.fd.Close()
+}
+
+func (ln *UnixListener) file() (*os.File, error) {
+	f, err := ln.fd.dup()
+	if err != nil {
+		return nil, err
+	}
+	return f, nil
+}
+
+// SetUnlinkOnClose sets whether the underlying socket file should be removed
+// from the file system when the listener is closed.
+//
+// The default behavior is to unlink the socket file only when package net created it.
+// That is, when the listener and the underlying socket file were created by a call to
+// Listen or ListenUnix, then by default closing the listener will remove the socket file.
+// but if the listener was created by a call to FileListener to use an already existing
+// socket file, then by default closing the listener will not remove the socket file.
+func (l *UnixListener) SetUnlinkOnClose(unlink bool) {
+	l.unlink = unlink
+}
+
+func (sl *sysListener) listenUnix(ctx context.Context, laddr *UnixAddr) (*UnixListener, error) {
+	fd, err := unixSocket(ctx, sl.network, laddr, nil, "listen", sl.ListenConfig.Control)
+	if err != nil {
+		return nil, err
+	}
+	return &UnixListener{fd: fd, path: fd.laddr.String(), unlink: true}, nil
+}
+
+func (sl *sysListener) listenUnixgram(ctx context.Context, laddr *UnixAddr) (*UnixConn, error) {
+	fd, err := unixSocket(ctx, sl.network, laddr, nil, "listen", sl.ListenConfig.Control)
+	if err != nil {
+		return nil, err
+	}
+	return newUnixConn(fd), nil
+}
diff --git a/contrib/go/_std_1.18/src/net/unixsock_readmsg_cloexec.go b/contrib/go/_std_1.19/src/net/unixsock_readmsg_cloexec.go
index fa4fd7d933..fa4fd7d933 100644
--- a/contrib/go/_std_1.18/src/net/unixsock_readmsg_cloexec.go
+++ b/contrib/go/_std_1.19/src/net/unixsock_readmsg_cloexec.go
diff --git a/contrib/go/_std_1.18/src/net/unixsock_readmsg_cmsg_cloexec.go b/contrib/go/_std_1.19/src/net/unixsock_readmsg_cmsg_cloexec.go
index 6b0de875ad..6b0de875ad 100644
--- a/contrib/go/_std_1.18/src/net/unixsock_readmsg_cmsg_cloexec.go
+++ b/contrib/go/_std_1.19/src/net/unixsock_readmsg_cmsg_cloexec.go
diff --git a/contrib/go/_std_1.19/src/net/url/url.go b/contrib/go/_std_1.19/src/net/url/url.go
new file mode 100644
index 0000000000..d7d2d54a0d
--- /dev/null
+++ b/contrib/go/_std_1.19/src/net/url/url.go
@@ -0,0 +1,1265 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package url parses URLs and implements query escaping.
+package url
+
+// See RFC 3986. This package generally follows RFC 3986, except where
+// it deviates for compatibility reasons. When sending changes, first
+// search old issues for history on decisions. Unit tests should also
+// contain references to issue numbers with details.
+
+import (
+	"errors"
+	"fmt"
+	"path"
+	"sort"
+	"strconv"
+	"strings"
+)
+
+// Error reports an error and the operation and URL that caused it.
+type Error struct {
+	Op  string
+	URL string
+	Err error
+}
+
+func (e *Error) Unwrap() error { return e.Err }
+func (e *Error) Error() string { return fmt.Sprintf("%s %q: %s", e.Op, e.URL, e.Err) }
+
+func (e *Error) Timeout() bool {
+	t, ok := e.Err.(interface {
+		Timeout() bool
+	})
+	return ok && t.Timeout()
+}
+
+func (e *Error) Temporary() bool {
+	t, ok := e.Err.(interface {
+		Temporary() bool
+	})
+	return ok && t.Temporary()
+}
+
+const upperhex = "0123456789ABCDEF"
+
+func ishex(c byte) bool {
+	switch {
+	case '0' <= c && c <= '9':
+		return true
+	case 'a' <= c && c <= 'f':
+		return true
+	case 'A' <= c && c <= 'F':
+		return true
+	}
+	return false
+}
+
+func unhex(c byte) byte {
+	switch {
+	case '0' <= c && c <= '9':
+		return c - '0'
+	case 'a' <= c && c <= 'f':
+		return c - 'a' + 10
+	case 'A' <= c && c <= 'F':
+		return c - 'A' + 10
+	}
+	return 0
+}
+
+type encoding int
+
+const (
+	encodePath encoding = 1 + iota
+	encodePathSegment
+	encodeHost
+	encodeZone
+	encodeUserPassword
+	encodeQueryComponent
+	encodeFragment
+)
+
+type EscapeError string
+
+func (e EscapeError) Error() string {
+	return "invalid URL escape " + strconv.Quote(string(e))
+}
+
+type InvalidHostError string
+
+func (e InvalidHostError) Error() string {
+	return "invalid character " + strconv.Quote(string(e)) + " in host name"
+}
+
+// Return true if the specified character should be escaped when
+// appearing in a URL string, according to RFC 3986.
+//
+// Please be informed that for now shouldEscape does not check all
+// reserved characters correctly. See golang.org/issue/5684.
+func shouldEscape(c byte, mode encoding) bool {
+	// §2.3 Unreserved characters (alphanum)
+	if 'a' <= c && c <= 'z' || 'A' <= c && c <= 'Z' || '0' <= c && c <= '9' {
+		return false
+	}
+
+	if mode == encodeHost || mode == encodeZone {
+		// §3.2.2 Host allows
+		//	sub-delims = "!" / "$" / "&" / "'" / "(" / ")" / "*" / "+" / "," / ";" / "="
+		// as part of reg-name.
+		// We add : because we include :port as part of host.
+		// We add [ ] because we include [ipv6]:port as part of host.
+		// We add < > because they're the only characters left that
+		// we could possibly allow, and Parse will reject them if we
+		// escape them (because hosts can't use %-encoding for
+		// ASCII bytes).
+		switch c {
+		case '!', '$', '&', '\'', '(', ')', '*', '+', ',', ';', '=', ':', '[', ']', '<', '>', '"':
+			return false
+		}
+	}
+
+	switch c {
+	case '-', '_', '.', '~': // §2.3 Unreserved characters (mark)
+		return false
+
+	case '$', '&', '+', ',', '/', ':', ';', '=', '?', '@': // §2.2 Reserved characters (reserved)
+		// Different sections of the URL allow a few of
+		// the reserved characters to appear unescaped.
+		switch mode {
+		case encodePath: // §3.3
+			// The RFC allows : @ & = + $ but saves / ; , for assigning
+			// meaning to individual path segments. This package
+			// only manipulates the path as a whole, so we allow those
+			// last three as well. That leaves only ? to escape.
+			return c == '?'
+
+		case encodePathSegment: // §3.3
+			// The RFC allows : @ & = + $ but saves / ; , for assigning
+			// meaning to individual path segments.
+			return c == '/' || c == ';' || c == ',' || c == '?'
+
+		case encodeUserPassword: // §3.2.1
+			// The RFC allows ';', ':', '&', '=', '+', '$', and ',' in
+			// userinfo, so we must escape only '@', '/', and '?'.
+			// The parsing of userinfo treats ':' as special so we must escape
+			// that too.
+			return c == '@' || c == '/' || c == '?' || c == ':'
+
+		case encodeQueryComponent: // §3.4
+			// The RFC reserves (so we must escape) everything.
+			return true
+
+		case encodeFragment: // §4.1
+			// The RFC text is silent but the grammar allows
+			// everything, so escape nothing.
+			return false
+		}
+	}
+
+	if mode == encodeFragment {
+		// RFC 3986 §2.2 allows not escaping sub-delims. A subset of sub-delims are
+		// included in reserved from RFC 2396 §2.2. The remaining sub-delims do not
+		// need to be escaped. To minimize potential breakage, we apply two restrictions:
+		// (1) we always escape sub-delims outside of the fragment, and (2) we always
+		// escape single quote to avoid breaking callers that had previously assumed that
+		// single quotes would be escaped. See issue #19917.
+		switch c {
+		case '!', '(', ')', '*':
+			return false
+		}
+	}
+
+	// Everything else must be escaped.
+	return true
+}
+
+// QueryUnescape does the inverse transformation of QueryEscape,
+// converting each 3-byte encoded substring of the form "%AB" into the
+// hex-decoded byte 0xAB.
+// It returns an error if any % is not followed by two hexadecimal
+// digits.
+func QueryUnescape(s string) (string, error) {
+	return unescape(s, encodeQueryComponent)
+}
+
+// PathUnescape does the inverse transformation of PathEscape,
+// converting each 3-byte encoded substring of the form "%AB" into the
+// hex-decoded byte 0xAB. It returns an error if any % is not followed
+// by two hexadecimal digits.
+//
+// PathUnescape is identical to QueryUnescape except that it does not
+// unescape '+' to ' ' (space).
+func PathUnescape(s string) (string, error) {
+	return unescape(s, encodePathSegment)
+}
+
+// unescape unescapes a string; the mode specifies
+// which section of the URL string is being unescaped.
+func unescape(s string, mode encoding) (string, error) {
+	// Count %, check that they're well-formed.
+	n := 0
+	hasPlus := false
+	for i := 0; i < len(s); {
+		switch s[i] {
+		case '%':
+			n++
+			if i+2 >= len(s) || !ishex(s[i+1]) || !ishex(s[i+2]) {
+				s = s[i:]
+				if len(s) > 3 {
+					s = s[:3]
+				}
+				return "", EscapeError(s)
+			}
+			// Per https://tools.ietf.org/html/rfc3986#page-21
+			// in the host component %-encoding can only be used
+			// for non-ASCII bytes.
+			// But https://tools.ietf.org/html/rfc6874#section-2
+			// introduces %25 being allowed to escape a percent sign
+			// in IPv6 scoped-address literals. Yay.
+			if mode == encodeHost && unhex(s[i+1]) < 8 && s[i:i+3] != "%25" {
+				return "", EscapeError(s[i : i+3])
+			}
+			if mode == encodeZone {
+				// RFC 6874 says basically "anything goes" for zone identifiers
+				// and that even non-ASCII can be redundantly escaped,
+				// but it seems prudent to restrict %-escaped bytes here to those
+				// that are valid host name bytes in their unescaped form.
+				// That is, you can use escaping in the zone identifier but not
+				// to introduce bytes you couldn't just write directly.
+				// But Windows puts spaces here! Yay.
+				v := unhex(s[i+1])<<4 | unhex(s[i+2])
+				if s[i:i+3] != "%25" && v != ' ' && shouldEscape(v, encodeHost) {
+					return "", EscapeError(s[i : i+3])
+				}
+			}
+			i += 3
+		case '+':
+			hasPlus = mode == encodeQueryComponent
+			i++
+		default:
+			if (mode == encodeHost || mode == encodeZone) && s[i] < 0x80 && shouldEscape(s[i], mode) {
+				return "", InvalidHostError(s[i : i+1])
+			}
+			i++
+		}
+	}
+
+	if n == 0 && !hasPlus {
+		return s, nil
+	}
+
+	var t strings.Builder
+	t.Grow(len(s) - 2*n)
+	for i := 0; i < len(s); i++ {
+		switch s[i] {
+		case '%':
+			t.WriteByte(unhex(s[i+1])<<4 | unhex(s[i+2]))
+			i += 2
+		case '+':
+			if mode == encodeQueryComponent {
+				t.WriteByte(' ')
+			} else {
+				t.WriteByte('+')
+			}
+		default:
+			t.WriteByte(s[i])
+		}
+	}
+	return t.String(), nil
+}
+
+// QueryEscape escapes the string so it can be safely placed
+// inside a URL query.
+func QueryEscape(s string) string {
+	return escape(s, encodeQueryComponent)
+}
+
+// PathEscape escapes the string so it can be safely placed inside a URL path segment,
+// replacing special characters (including /) with %XX sequences as needed.
+func PathEscape(s string) string {
+	return escape(s, encodePathSegment)
+}
+
+func escape(s string, mode encoding) string {
+	spaceCount, hexCount := 0, 0
+	for i := 0; i < len(s); i++ {
+		c := s[i]
+		if shouldEscape(c, mode) {
+			if c == ' ' && mode == encodeQueryComponent {
+				spaceCount++
+			} else {
+				hexCount++
+			}
+		}
+	}
+
+	if spaceCount == 0 && hexCount == 0 {
+		return s
+	}
+
+	var buf [64]byte
+	var t []byte
+
+	required := len(s) + 2*hexCount
+	if required <= len(buf) {
+		t = buf[:required]
+	} else {
+		t = make([]byte, required)
+	}
+
+	if hexCount == 0 {
+		copy(t, s)
+		for i := 0; i < len(s); i++ {
+			if s[i] == ' ' {
+				t[i] = '+'
+			}
+		}
+		return string(t)
+	}
+
+	j := 0
+	for i := 0; i < len(s); i++ {
+		switch c := s[i]; {
+		case c == ' ' && mode == encodeQueryComponent:
+			t[j] = '+'
+			j++
+		case shouldEscape(c, mode):
+			t[j] = '%'
+			t[j+1] = upperhex[c>>4]
+			t[j+2] = upperhex[c&15]
+			j += 3
+		default:
+			t[j] = s[i]
+			j++
+		}
+	}
+	return string(t)
+}
+
+// A URL represents a parsed URL (technically, a URI reference).
+//
+// The general form represented is:
+//
+//	[scheme:][//[userinfo@]host][/]path[?query][#fragment]
+//
+// URLs that do not start with a slash after the scheme are interpreted as:
+//
+//	scheme:opaque[?query][#fragment]
+//
+// Note that the Path field is stored in decoded form: /%47%6f%2f becomes /Go/.
+// A consequence is that it is impossible to tell which slashes in the Path were
+// slashes in the raw URL and which were %2f. This distinction is rarely important,
+// but when it is, the code should use RawPath, an optional field which only gets
+// set if the default encoding is different from Path.
+//
+// URL's String method uses the EscapedPath method to obtain the path. See the
+// EscapedPath method for more details.
+type URL struct {
+	Scheme      string
+	Opaque      string    // encoded opaque data
+	User        *Userinfo // username and password information
+	Host        string    // host or host:port
+	Path        string    // path (relative paths may omit leading slash)
+	RawPath     string    // encoded path hint (see EscapedPath method)
+	OmitHost    bool      // do not emit empty host (authority)
+	ForceQuery  bool      // append a query ('?') even if RawQuery is empty
+	RawQuery    string    // encoded query values, without '?'
+	Fragment    string    // fragment for references, without '#'
+	RawFragment string    // encoded fragment hint (see EscapedFragment method)
+}
+
+// User returns a Userinfo containing the provided username
+// and no password set.
+func User(username string) *Userinfo {
+	return &Userinfo{username, "", false}
+}
+
+// UserPassword returns a Userinfo containing the provided username
+// and password.
+//
+// This functionality should only be used with legacy web sites.
+// RFC 2396 warns that interpreting Userinfo this way
+// “is NOT RECOMMENDED, because the passing of authentication
+// information in clear text (such as URI) has proven to be a
+// security risk in almost every case where it has been used.”
+func UserPassword(username, password string) *Userinfo {
+	return &Userinfo{username, password, true}
+}
+
+// The Userinfo type is an immutable encapsulation of username and
+// password details for a URL. An existing Userinfo value is guaranteed
+// to have a username set (potentially empty, as allowed by RFC 2396),
+// and optionally a password.
+type Userinfo struct {
+	username    string
+	password    string
+	passwordSet bool
+}
+
+// Username returns the username.
+func (u *Userinfo) Username() string {
+	if u == nil {
+		return ""
+	}
+	return u.username
+}
+
+// Password returns the password in case it is set, and whether it is set.
+func (u *Userinfo) Password() (string, bool) {
+	if u == nil {
+		return "", false
+	}
+	return u.password, u.passwordSet
+}
+
+// String returns the encoded userinfo information in the standard form
+// of "username[:password]".
+func (u *Userinfo) String() string {
+	if u == nil {
+		return ""
+	}
+	s := escape(u.username, encodeUserPassword)
+	if u.passwordSet {
+		s += ":" + escape(u.password, encodeUserPassword)
+	}
+	return s
+}
+
+// Maybe rawURL is of the form scheme:path.
+// (Scheme must be [a-zA-Z][a-zA-Z0-9+.-]*)
+// If so, return scheme, path; else return "", rawURL.
+func getScheme(rawURL string) (scheme, path string, err error) {
+	for i := 0; i < len(rawURL); i++ {
+		c := rawURL[i]
+		switch {
+		case 'a' <= c && c <= 'z' || 'A' <= c && c <= 'Z':
+		// do nothing
+		case '0' <= c && c <= '9' || c == '+' || c == '-' || c == '.':
+			if i == 0 {
+				return "", rawURL, nil
+			}
+		case c == ':':
+			if i == 0 {
+				return "", "", errors.New("missing protocol scheme")
+			}
+			return rawURL[:i], rawURL[i+1:], nil
+		default:
+			// we have encountered an invalid character,
+			// so there is no valid scheme
+			return "", rawURL, nil
+		}
+	}
+	return "", rawURL, nil
+}
+
+// Parse parses a raw url into a URL structure.
+//
+// The url may be relative (a path, without a host) or absolute
+// (starting with a scheme). Trying to parse a hostname and path
+// without a scheme is invalid but may not necessarily return an
+// error, due to parsing ambiguities.
+func Parse(rawURL string) (*URL, error) {
+	// Cut off #frag
+	u, frag, _ := strings.Cut(rawURL, "#")
+	url, err := parse(u, false)
+	if err != nil {
+		return nil, &Error{"parse", u, err}
+	}
+	if frag == "" {
+		return url, nil
+	}
+	if err = url.setFragment(frag); err != nil {
+		return nil, &Error{"parse", rawURL, err}
+	}
+	return url, nil
+}
+
+// ParseRequestURI parses a raw url into a URL structure. It assumes that
+// url was received in an HTTP request, so the url is interpreted
+// only as an absolute URI or an absolute path.
+// The string url is assumed not to have a #fragment suffix.
+// (Web browsers strip #fragment before sending the URL to a web server.)
+func ParseRequestURI(rawURL string) (*URL, error) {
+	url, err := parse(rawURL, true)
+	if err != nil {
+		return nil, &Error{"parse", rawURL, err}
+	}
+	return url, nil
+}
+
+// parse parses a URL from a string in one of two contexts. If
+// viaRequest is true, the URL is assumed to have arrived via an HTTP request,
+// in which case only absolute URLs or path-absolute relative URLs are allowed.
+// If viaRequest is false, all forms of relative URLs are allowed.
+func parse(rawURL string, viaRequest bool) (*URL, error) {
+	var rest string
+	var err error
+
+	if stringContainsCTLByte(rawURL) {
+		return nil, errors.New("net/url: invalid control character in URL")
+	}
+
+	if rawURL == "" && viaRequest {
+		return nil, errors.New("empty url")
+	}
+	url := new(URL)
+
+	if rawURL == "*" {
+		url.Path = "*"
+		return url, nil
+	}
+
+	// Split off possible leading "http:", "mailto:", etc.
+	// Cannot contain escaped characters.
+	if url.Scheme, rest, err = getScheme(rawURL); err != nil {
+		return nil, err
+	}
+	url.Scheme = strings.ToLower(url.Scheme)
+
+	if strings.HasSuffix(rest, "?") && strings.Count(rest, "?") == 1 {
+		url.ForceQuery = true
+		rest = rest[:len(rest)-1]
+	} else {
+		rest, url.RawQuery, _ = strings.Cut(rest, "?")
+	}
+
+	if !strings.HasPrefix(rest, "/") {
+		if url.Scheme != "" {
+			// We consider rootless paths per RFC 3986 as opaque.
+			url.Opaque = rest
+			return url, nil
+		}
+		if viaRequest {
+			return nil, errors.New("invalid URI for request")
+		}
+
+		// Avoid confusion with malformed schemes, like cache_object:foo/bar.
+		// See golang.org/issue/16822.
+		//
+		// RFC 3986, §3.3:
+		// In addition, a URI reference (Section 4.1) may be a relative-path reference,
+		// in which case the first path segment cannot contain a colon (":") character.
+		if segment, _, _ := strings.Cut(rest, "/"); strings.Contains(segment, ":") {
+			// First path segment has colon. Not allowed in relative URL.
+			return nil, errors.New("first path segment in URL cannot contain colon")
+		}
+	}
+
+	if (url.Scheme != "" || !viaRequest && !strings.HasPrefix(rest, "///")) && strings.HasPrefix(rest, "//") {
+		var authority string
+		authority, rest = rest[2:], ""
+		if i := strings.Index(authority, "/"); i >= 0 {
+			authority, rest = authority[:i], authority[i:]
+		}
+		url.User, url.Host, err = parseAuthority(authority)
+		if err != nil {
+			return nil, err
+		}
+	} else if url.Scheme != "" && strings.HasPrefix(rest, "/") {
+		// OmitHost is set to true when rawURL has an empty host (authority).
+		// See golang.org/issue/46059.
+		url.OmitHost = true
+	}
+
+	// Set Path and, optionally, RawPath.
+	// RawPath is a hint of the encoding of Path. We don't want to set it if
+	// the default escaping of Path is equivalent, to help make sure that people
+	// don't rely on it in general.
+	if err := url.setPath(rest); err != nil {
+		return nil, err
+	}
+	return url, nil
+}
+
+func parseAuthority(authority string) (user *Userinfo, host string, err error) {
+	i := strings.LastIndex(authority, "@")
+	if i < 0 {
+		host, err = parseHost(authority)
+	} else {
+		host, err = parseHost(authority[i+1:])
+	}
+	if err != nil {
+		return nil, "", err
+	}
+	if i < 0 {
+		return nil, host, nil
+	}
+	userinfo := authority[:i]
+	if !validUserinfo(userinfo) {
+		return nil, "", errors.New("net/url: invalid userinfo")
+	}
+	if !strings.Contains(userinfo, ":") {
+		if userinfo, err = unescape(userinfo, encodeUserPassword); err != nil {
+			return nil, "", err
+		}
+		user = User(userinfo)
+	} else {
+		username, password, _ := strings.Cut(userinfo, ":")
+		if username, err = unescape(username, encodeUserPassword); err != nil {
+			return nil, "", err
+		}
+		if password, err = unescape(password, encodeUserPassword); err != nil {
+			return nil, "", err
+		}
+		user = UserPassword(username, password)
+	}
+	return user, host, nil
+}
+
+// parseHost parses host as an authority without user
+// information. That is, as host[:port].
+func parseHost(host string) (string, error) {
+	if strings.HasPrefix(host, "[") {
+		// Parse an IP-Literal in RFC 3986 and RFC 6874.
+		// E.g., "[fe80::1]", "[fe80::1%25en0]", "[fe80::1]:80".
+		i := strings.LastIndex(host, "]")
+		if i < 0 {
+			return "", errors.New("missing ']' in host")
+		}
+		colonPort := host[i+1:]
+		if !validOptionalPort(colonPort) {
+			return "", fmt.Errorf("invalid port %q after host", colonPort)
+		}
+
+		// RFC 6874 defines that %25 (%-encoded percent) introduces
+		// the zone identifier, and the zone identifier can use basically
+		// any %-encoding it likes. That's different from the host, which
+		// can only %-encode non-ASCII bytes.
+		// We do impose some restrictions on the zone, to avoid stupidity
+		// like newlines.
+		zone := strings.Index(host[:i], "%25")
+		if zone >= 0 {
+			host1, err := unescape(host[:zone], encodeHost)
+			if err != nil {
+				return "", err
+			}
+			host2, err := unescape(host[zone:i], encodeZone)
+			if err != nil {
+				return "", err
+			}
+			host3, err := unescape(host[i:], encodeHost)
+			if err != nil {
+				return "", err
+			}
+			return host1 + host2 + host3, nil
+		}
+	} else if i := strings.LastIndex(host, ":"); i != -1 {
+		colonPort := host[i:]
+		if !validOptionalPort(colonPort) {
+			return "", fmt.Errorf("invalid port %q after host", colonPort)
+		}
+	}
+
+	var err error
+	if host, err = unescape(host, encodeHost); err != nil {
+		return "", err
+	}
+	return host, nil
+}
+
+// setPath sets the Path and RawPath fields of the URL based on the provided
+// escaped path p. It maintains the invariant that RawPath is only specified
+// when it differs from the default encoding of the path.
+// For example:
+// - setPath("/foo/bar")   will set Path="/foo/bar" and RawPath=""
+// - setPath("/foo%2fbar") will set Path="/foo/bar" and RawPath="/foo%2fbar"
+// setPath will return an error only if the provided path contains an invalid
+// escaping.
+func (u *URL) setPath(p string) error {
+	path, err := unescape(p, encodePath)
+	if err != nil {
+		return err
+	}
+	u.Path = path
+	if escp := escape(path, encodePath); p == escp {
+		// Default encoding is fine.
+		u.RawPath = ""
+	} else {
+		u.RawPath = p
+	}
+	return nil
+}
+
+// EscapedPath returns the escaped form of u.Path.
+// In general there are multiple possible escaped forms of any path.
+// EscapedPath returns u.RawPath when it is a valid escaping of u.Path.
+// Otherwise EscapedPath ignores u.RawPath and computes an escaped
+// form on its own.
+// The String and RequestURI methods use EscapedPath to construct
+// their results.
+// In general, code should call EscapedPath instead of
+// reading u.RawPath directly.
+func (u *URL) EscapedPath() string {
+	if u.RawPath != "" && validEncoded(u.RawPath, encodePath) {
+		p, err := unescape(u.RawPath, encodePath)
+		if err == nil && p == u.Path {
+			return u.RawPath
+		}
+	}
+	if u.Path == "*" {
+		return "*" // don't escape (Issue 11202)
+	}
+	return escape(u.Path, encodePath)
+}
+
+// validEncoded reports whether s is a valid encoded path or fragment,
+// according to mode.
+// It must not contain any bytes that require escaping during encoding.
+func validEncoded(s string, mode encoding) bool {
+	for i := 0; i < len(s); i++ {
+		// RFC 3986, Appendix A.
+		// pchar = unreserved / pct-encoded / sub-delims / ":" / "@".
+		// shouldEscape is not quite compliant with the RFC,
+		// so we check the sub-delims ourselves and let
+		// shouldEscape handle the others.
+		switch s[i] {
+		case '!', '$', '&', '\'', '(', ')', '*', '+', ',', ';', '=', ':', '@':
+			// ok
+		case '[', ']':
+			// ok - not specified in RFC 3986 but left alone by modern browsers
+		case '%':
+			// ok - percent encoded, will decode
+		default:
+			if shouldEscape(s[i], mode) {
+				return false
+			}
+		}
+	}
+	return true
+}
+
+// setFragment is like setPath but for Fragment/RawFragment.
+func (u *URL) setFragment(f string) error {
+	frag, err := unescape(f, encodeFragment)
+	if err != nil {
+		return err
+	}
+	u.Fragment = frag
+	if escf := escape(frag, encodeFragment); f == escf {
+		// Default encoding is fine.
+		u.RawFragment = ""
+	} else {
+		u.RawFragment = f
+	}
+	return nil
+}
+
+// EscapedFragment returns the escaped form of u.Fragment.
+// In general there are multiple possible escaped forms of any fragment.
+// EscapedFragment returns u.RawFragment when it is a valid escaping of u.Fragment.
+// Otherwise EscapedFragment ignores u.RawFragment and computes an escaped
+// form on its own.
+// The String method uses EscapedFragment to construct its result.
+// In general, code should call EscapedFragment instead of
+// reading u.RawFragment directly.
+func (u *URL) EscapedFragment() string {
+	if u.RawFragment != "" && validEncoded(u.RawFragment, encodeFragment) {
+		f, err := unescape(u.RawFragment, encodeFragment)
+		if err == nil && f == u.Fragment {
+			return u.RawFragment
+		}
+	}
+	return escape(u.Fragment, encodeFragment)
+}
+
+// validOptionalPort reports whether port is either an empty string
+// or matches /^:\d*$/
+func validOptionalPort(port string) bool {
+	if port == "" {
+		return true
+	}
+	if port[0] != ':' {
+		return false
+	}
+	for _, b := range port[1:] {
+		if b < '0' || b > '9' {
+			return false
+		}
+	}
+	return true
+}
+
+// String reassembles the URL into a valid URL string.
+// The general form of the result is one of:
+//
+//	scheme:opaque?query#fragment
+//	scheme://userinfo@host/path?query#fragment
+//
+// If u.Opaque is non-empty, String uses the first form;
+// otherwise it uses the second form.
+// Any non-ASCII characters in host are escaped.
+// To obtain the path, String uses u.EscapedPath().
+//
+// In the second form, the following rules apply:
+//   - if u.Scheme is empty, scheme: is omitted.
+//   - if u.User is nil, userinfo@ is omitted.
+//   - if u.Host is empty, host/ is omitted.
+//   - if u.Scheme and u.Host are empty and u.User is nil,
+//     the entire scheme://userinfo@host/ is omitted.
+//   - if u.Host is non-empty and u.Path begins with a /,
+//     the form host/path does not add its own /.
+//   - if u.RawQuery is empty, ?query is omitted.
+//   - if u.Fragment is empty, #fragment is omitted.
+func (u *URL) String() string {
+	var buf strings.Builder
+	if u.Scheme != "" {
+		buf.WriteString(u.Scheme)
+		buf.WriteByte(':')
+	}
+	if u.Opaque != "" {
+		buf.WriteString(u.Opaque)
+	} else {
+		if u.Scheme != "" || u.Host != "" || u.User != nil {
+			if u.OmitHost && u.Host == "" && u.User == nil {
+				// omit empty host
+			} else {
+				if u.Host != "" || u.Path != "" || u.User != nil {
+					buf.WriteString("//")
+				}
+				if ui := u.User; ui != nil {
+					buf.WriteString(ui.String())
+					buf.WriteByte('@')
+				}
+				if h := u.Host; h != "" {
+					buf.WriteString(escape(h, encodeHost))
+				}
+			}
+		}
+		path := u.EscapedPath()
+		if path != "" && path[0] != '/' && u.Host != "" {
+			buf.WriteByte('/')
+		}
+		if buf.Len() == 0 {
+			// RFC 3986 §4.2
+			// A path segment that contains a colon character (e.g., "this:that")
+			// cannot be used as the first segment of a relative-path reference, as
+			// it would be mistaken for a scheme name. Such a segment must be
+			// preceded by a dot-segment (e.g., "./this:that") to make a relative-
+			// path reference.
+			if segment, _, _ := strings.Cut(path, "/"); strings.Contains(segment, ":") {
+				buf.WriteString("./")
+			}
+		}
+		buf.WriteString(path)
+	}
+	if u.ForceQuery || u.RawQuery != "" {
+		buf.WriteByte('?')
+		buf.WriteString(u.RawQuery)
+	}
+	if u.Fragment != "" {
+		buf.WriteByte('#')
+		buf.WriteString(u.EscapedFragment())
+	}
+	return buf.String()
+}
+
+// Redacted is like String but replaces any password with "xxxxx".
+// Only the password in u.URL is redacted.
+func (u *URL) Redacted() string {
+	if u == nil {
+		return ""
+	}
+
+	ru := *u
+	if _, has := ru.User.Password(); has {
+		ru.User = UserPassword(ru.User.Username(), "xxxxx")
+	}
+	return ru.String()
+}
+
+// Values maps a string key to a list of values.
+// It is typically used for query parameters and form values.
+// Unlike in the http.Header map, the keys in a Values map
+// are case-sensitive.
+type Values map[string][]string
+
+// Get gets the first value associated with the given key.
+// If there are no values associated with the key, Get returns
+// the empty string. To access multiple values, use the map
+// directly.
+func (v Values) Get(key string) string {
+	if v == nil {
+		return ""
+	}
+	vs := v[key]
+	if len(vs) == 0 {
+		return ""
+	}
+	return vs[0]
+}
+
+// Set sets the key to value. It replaces any existing
+// values.
+func (v Values) Set(key, value string) {
+	v[key] = []string{value}
+}
+
+// Add adds the value to key. It appends to any existing
+// values associated with key.
+func (v Values) Add(key, value string) {
+	v[key] = append(v[key], value)
+}
+
+// Del deletes the values associated with key.
+func (v Values) Del(key string) {
+	delete(v, key)
+}
+
+// Has checks whether a given key is set.
+func (v Values) Has(key string) bool {
+	_, ok := v[key]
+	return ok
+}
+
+// ParseQuery parses the URL-encoded query string and returns
+// a map listing the values specified for each key.
+// ParseQuery always returns a non-nil map containing all the
+// valid query parameters found; err describes the first decoding error
+// encountered, if any.
+//
+// Query is expected to be a list of key=value settings separated by ampersands.
+// A setting without an equals sign is interpreted as a key set to an empty
+// value.
+// Settings containing a non-URL-encoded semicolon are considered invalid.
+func ParseQuery(query string) (Values, error) {
+	m := make(Values)
+	err := parseQuery(m, query)
+	return m, err
+}
+
+func parseQuery(m Values, query string) (err error) {
+	for query != "" {
+		var key string
+		key, query, _ = strings.Cut(query, "&")
+		if strings.Contains(key, ";") {
+			err = fmt.Errorf("invalid semicolon separator in query")
+			continue
+		}
+		if key == "" {
+			continue
+		}
+		key, value, _ := strings.Cut(key, "=")
+		key, err1 := QueryUnescape(key)
+		if err1 != nil {
+			if err == nil {
+				err = err1
+			}
+			continue
+		}
+		value, err1 = QueryUnescape(value)
+		if err1 != nil {
+			if err == nil {
+				err = err1
+			}
+			continue
+		}
+		m[key] = append(m[key], value)
+	}
+	return err
+}
+
+// Encode encodes the values into “URL encoded” form
+// ("bar=baz&foo=quux") sorted by key.
+func (v Values) Encode() string {
+	if v == nil {
+		return ""
+	}
+	var buf strings.Builder
+	keys := make([]string, 0, len(v))
+	for k := range v {
+		keys = append(keys, k)
+	}
+	sort.Strings(keys)
+	for _, k := range keys {
+		vs := v[k]
+		keyEscaped := QueryEscape(k)
+		for _, v := range vs {
+			if buf.Len() > 0 {
+				buf.WriteByte('&')
+			}
+			buf.WriteString(keyEscaped)
+			buf.WriteByte('=')
+			buf.WriteString(QueryEscape(v))
+		}
+	}
+	return buf.String()
+}
+
+// resolvePath applies special path segments from refs and applies
+// them to base, per RFC 3986.
+func resolvePath(base, ref string) string {
+	var full string
+	if ref == "" {
+		full = base
+	} else if ref[0] != '/' {
+		i := strings.LastIndex(base, "/")
+		full = base[:i+1] + ref
+	} else {
+		full = ref
+	}
+	if full == "" {
+		return ""
+	}
+
+	var (
+		elem string
+		dst  strings.Builder
+	)
+	first := true
+	remaining := full
+	// We want to return a leading '/', so write it now.
+	dst.WriteByte('/')
+	found := true
+	for found {
+		elem, remaining, found = strings.Cut(remaining, "/")
+		if elem == "." {
+			first = false
+			// drop
+			continue
+		}
+
+		if elem == ".." {
+			// Ignore the leading '/' we already wrote.
+			str := dst.String()[1:]
+			index := strings.LastIndexByte(str, '/')
+
+			dst.Reset()
+			dst.WriteByte('/')
+			if index == -1 {
+				first = true
+			} else {
+				dst.WriteString(str[:index])
+			}
+		} else {
+			if !first {
+				dst.WriteByte('/')
+			}
+			dst.WriteString(elem)
+			first = false
+		}
+	}
+
+	if elem == "." || elem == ".." {
+		dst.WriteByte('/')
+	}
+
+	// We wrote an initial '/', but we don't want two.
+	r := dst.String()
+	if len(r) > 1 && r[1] == '/' {
+		r = r[1:]
+	}
+	return r
+}
+
+// IsAbs reports whether the URL is absolute.
+// Absolute means that it has a non-empty scheme.
+func (u *URL) IsAbs() bool {
+	return u.Scheme != ""
+}
+
+// Parse parses a URL in the context of the receiver. The provided URL
+// may be relative or absolute. Parse returns nil, err on parse
+// failure, otherwise its return value is the same as ResolveReference.
+func (u *URL) Parse(ref string) (*URL, error) {
+	refURL, err := Parse(ref)
+	if err != nil {
+		return nil, err
+	}
+	return u.ResolveReference(refURL), nil
+}
+
+// ResolveReference resolves a URI reference to an absolute URI from
+// an absolute base URI u, per RFC 3986 Section 5.2. The URI reference
+// may be relative or absolute. ResolveReference always returns a new
+// URL instance, even if the returned URL is identical to either the
+// base or reference. If ref is an absolute URL, then ResolveReference
+// ignores base and returns a copy of ref.
+func (u *URL) ResolveReference(ref *URL) *URL {
+	url := *ref
+	if ref.Scheme == "" {
+		url.Scheme = u.Scheme
+	}
+	if ref.Scheme != "" || ref.Host != "" || ref.User != nil {
+		// The "absoluteURI" or "net_path" cases.
+		// We can ignore the error from setPath since we know we provided a
+		// validly-escaped path.
+		url.setPath(resolvePath(ref.EscapedPath(), ""))
+		return &url
+	}
+	if ref.Opaque != "" {
+		url.User = nil
+		url.Host = ""
+		url.Path = ""
+		return &url
+	}
+	if ref.Path == "" && !ref.ForceQuery && ref.RawQuery == "" {
+		url.RawQuery = u.RawQuery
+		if ref.Fragment == "" {
+			url.Fragment = u.Fragment
+			url.RawFragment = u.RawFragment
+		}
+	}
+	// The "abs_path" or "rel_path" cases.
+	url.Host = u.Host
+	url.User = u.User
+	url.setPath(resolvePath(u.EscapedPath(), ref.EscapedPath()))
+	return &url
+}
+
+// Query parses RawQuery and returns the corresponding values.
+// It silently discards malformed value pairs.
+// To check errors use ParseQuery.
+func (u *URL) Query() Values {
+	v, _ := ParseQuery(u.RawQuery)
+	return v
+}
+
+// RequestURI returns the encoded path?query or opaque?query
+// string that would be used in an HTTP request for u.
+func (u *URL) RequestURI() string {
+	result := u.Opaque
+	if result == "" {
+		result = u.EscapedPath()
+		if result == "" {
+			result = "/"
+		}
+	} else {
+		if strings.HasPrefix(result, "//") {
+			result = u.Scheme + ":" + result
+		}
+	}
+	if u.ForceQuery || u.RawQuery != "" {
+		result += "?" + u.RawQuery
+	}
+	return result
+}
+
+// Hostname returns u.Host, stripping any valid port number if present.
+//
+// If the result is enclosed in square brackets, as literal IPv6 addresses are,
+// the square brackets are removed from the result.
+func (u *URL) Hostname() string {
+	host, _ := splitHostPort(u.Host)
+	return host
+}
+
+// Port returns the port part of u.Host, without the leading colon.
+//
+// If u.Host doesn't contain a valid numeric port, Port returns an empty string.
+func (u *URL) Port() string {
+	_, port := splitHostPort(u.Host)
+	return port
+}
+
+// splitHostPort separates host and port. If the port is not valid, it returns
+// the entire input as host, and it doesn't check the validity of the host.
+// Unlike net.SplitHostPort, but per RFC 3986, it requires ports to be numeric.
+func splitHostPort(hostPort string) (host, port string) {
+	host = hostPort
+
+	colon := strings.LastIndexByte(host, ':')
+	if colon != -1 && validOptionalPort(host[colon:]) {
+		host, port = host[:colon], host[colon+1:]
+	}
+
+	if strings.HasPrefix(host, "[") && strings.HasSuffix(host, "]") {
+		host = host[1 : len(host)-1]
+	}
+
+	return
+}
+
+// Marshaling interface implementations.
+// Would like to implement MarshalText/UnmarshalText but that will change the JSON representation of URLs.
+
+func (u *URL) MarshalBinary() (text []byte, err error) {
+	return []byte(u.String()), nil
+}
+
+func (u *URL) UnmarshalBinary(text []byte) error {
+	u1, err := Parse(string(text))
+	if err != nil {
+		return err
+	}
+	*u = *u1
+	return nil
+}
+
+// JoinPath returns a new URL with the provided path elements joined to
+// any existing path and the resulting path cleaned of any ./ or ../ elements.
+// Any sequences of multiple / characters will be reduced to a single /.
+func (u *URL) JoinPath(elem ...string) *URL {
+	elem = append([]string{u.EscapedPath()}, elem...)
+	var p string
+	if !strings.HasPrefix(elem[0], "/") {
+		// Return a relative path if u is relative,
+		// but ensure that it contains no ../ elements.
+		elem[0] = "/" + elem[0]
+		p = path.Join(elem...)[1:]
+	} else {
+		p = path.Join(elem...)
+	}
+	// path.Join will remove any trailing slashes.
+	// Preserve at least one.
+	if strings.HasSuffix(elem[len(elem)-1], "/") && !strings.HasSuffix(p, "/") {
+		p += "/"
+	}
+	url := *u
+	url.setPath(p)
+	return &url
+}
+
+// validUserinfo reports whether s is a valid userinfo string per RFC 3986
+// Section 3.2.1:
+//
+//	userinfo    = *( unreserved / pct-encoded / sub-delims / ":" )
+//	unreserved  = ALPHA / DIGIT / "-" / "." / "_" / "~"
+//	sub-delims  = "!" / "$" / "&" / "'" / "(" / ")"
+//	              / "*" / "+" / "," / ";" / "="
+//
+// It doesn't validate pct-encoded. The caller does that via func unescape.
+func validUserinfo(s string) bool {
+	for _, r := range s {
+		if 'A' <= r && r <= 'Z' {
+			continue
+		}
+		if 'a' <= r && r <= 'z' {
+			continue
+		}
+		if '0' <= r && r <= '9' {
+			continue
+		}
+		switch r {
+		case '-', '.', '_', ':', '~', '!', '$', '&', '\'',
+			'(', ')', '*', '+', ',', ';', '=', '%', '@':
+			continue
+		default:
+			return false
+		}
+	}
+	return true
+}
+
+// stringContainsCTLByte reports whether s contains any ASCII control character.
+func stringContainsCTLByte(s string) bool {
+	for i := 0; i < len(s); i++ {
+		b := s[i]
+		if b < ' ' || b == 0x7f {
+			return true
+		}
+	}
+	return false
+}
+
+// JoinPath returns a URL string with the provided path elements joined to
+// the existing path of base and the resulting path cleaned of any ./ or ../ elements.
+func JoinPath(base string, elem ...string) (result string, err error) {
+	url, err := Parse(base)
+	if err != nil {
+		return
+	}
+	result = url.JoinPath(elem...).String()
+	return
+}
diff --git a/contrib/go/_std_1.18/src/net/writev_unix.go b/contrib/go/_std_1.19/src/net/writev_unix.go
index 51ab29dc31..51ab29dc31 100644
--- a/contrib/go/_std_1.18/src/net/writev_unix.go
+++ b/contrib/go/_std_1.19/src/net/writev_unix.go
diff --git a/contrib/go/_std_1.18/src/os/dir.go b/contrib/go/_std_1.19/src/os/dir.go
index 5306bcb3ba..5306bcb3ba 100644
--- a/contrib/go/_std_1.18/src/os/dir.go
+++ b/contrib/go/_std_1.19/src/os/dir.go
diff --git a/contrib/go/_std_1.18/src/os/dir_darwin.go b/contrib/go/_std_1.19/src/os/dir_darwin.go
index deba3eb37f..deba3eb37f 100644
--- a/contrib/go/_std_1.18/src/os/dir_darwin.go
+++ b/contrib/go/_std_1.19/src/os/dir_darwin.go
diff --git a/contrib/go/_std_1.18/src/os/dir_unix.go b/contrib/go/_std_1.19/src/os/dir_unix.go
index 9b3871a3e8..9b3871a3e8 100644
--- a/contrib/go/_std_1.18/src/os/dir_unix.go
+++ b/contrib/go/_std_1.19/src/os/dir_unix.go
diff --git a/contrib/go/_std_1.18/src/os/dirent_linux.go b/contrib/go/_std_1.19/src/os/dirent_linux.go
index 74a3431121..74a3431121 100644
--- a/contrib/go/_std_1.18/src/os/dirent_linux.go
+++ b/contrib/go/_std_1.19/src/os/dirent_linux.go
diff --git a/contrib/go/_std_1.19/src/os/endian_little.go b/contrib/go/_std_1.19/src/os/endian_little.go
new file mode 100644
index 0000000000..a7cf1cdda8
--- /dev/null
+++ b/contrib/go/_std_1.19/src/os/endian_little.go
@@ -0,0 +1,9 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+//
+//go:build 386 || amd64 || arm || arm64 || loong64 || ppc64le || mips64le || mipsle || riscv64 || wasm
+
+package os
+
+const isBigEndian = false
diff --git a/contrib/go/_std_1.18/src/os/env.go b/contrib/go/_std_1.19/src/os/env.go
index 330297b36a..330297b36a 100644
--- a/contrib/go/_std_1.18/src/os/env.go
+++ b/contrib/go/_std_1.19/src/os/env.go
diff --git a/contrib/go/_std_1.18/src/os/error.go b/contrib/go/_std_1.19/src/os/error.go
index fe8f2a8446..fe8f2a8446 100644
--- a/contrib/go/_std_1.18/src/os/error.go
+++ b/contrib/go/_std_1.19/src/os/error.go
diff --git a/contrib/go/_std_1.18/src/os/error_errno.go b/contrib/go/_std_1.19/src/os/error_errno.go
index c8140461a4..c8140461a4 100644
--- a/contrib/go/_std_1.18/src/os/error_errno.go
+++ b/contrib/go/_std_1.19/src/os/error_errno.go
diff --git a/contrib/go/_std_1.19/src/os/error_posix.go b/contrib/go/_std_1.19/src/os/error_posix.go
new file mode 100644
index 0000000000..5ca2e60e5b
--- /dev/null
+++ b/contrib/go/_std_1.19/src/os/error_posix.go
@@ -0,0 +1,18 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm) || windows
+
+package os
+
+import "syscall"
+
+// wrapSyscallError takes an error and a syscall name. If the error is
+// a syscall.Errno, it wraps it in a os.SyscallError using the syscall name.
+func wrapSyscallError(name string, err error) error {
+	if _, ok := err.(syscall.Errno); ok {
+		err = NewSyscallError(name, err)
+	}
+	return err
+}
diff --git a/contrib/go/_std_1.18/src/os/exec.go b/contrib/go/_std_1.19/src/os/exec.go
index 9eb3166ecb..9eb3166ecb 100644
--- a/contrib/go/_std_1.18/src/os/exec.go
+++ b/contrib/go/_std_1.19/src/os/exec.go
diff --git a/contrib/go/_std_1.19/src/os/exec_posix.go b/contrib/go/_std_1.19/src/os/exec_posix.go
new file mode 100644
index 0000000000..e1e7d53a27
--- /dev/null
+++ b/contrib/go/_std_1.19/src/os/exec_posix.go
@@ -0,0 +1,136 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm) || windows
+
+package os
+
+import (
+	"internal/itoa"
+	"internal/syscall/execenv"
+	"runtime"
+	"syscall"
+)
+
+// The only signal values guaranteed to be present in the os package on all
+// systems are os.Interrupt (send the process an interrupt) and os.Kill (force
+// the process to exit). On Windows, sending os.Interrupt to a process with
+// os.Process.Signal is not implemented; it will return an error instead of
+// sending a signal.
+var (
+	Interrupt Signal = syscall.SIGINT
+	Kill      Signal = syscall.SIGKILL
+)
+
+func startProcess(name string, argv []string, attr *ProcAttr) (p *Process, err error) {
+	// If there is no SysProcAttr (ie. no Chroot or changed
+	// UID/GID), double-check existence of the directory we want
+	// to chdir into. We can make the error clearer this way.
+	if attr != nil && attr.Sys == nil && attr.Dir != "" {
+		if _, err := Stat(attr.Dir); err != nil {
+			pe := err.(*PathError)
+			pe.Op = "chdir"
+			return nil, pe
+		}
+	}
+
+	sysattr := &syscall.ProcAttr{
+		Dir: attr.Dir,
+		Env: attr.Env,
+		Sys: attr.Sys,
+	}
+	if sysattr.Env == nil {
+		sysattr.Env, err = execenv.Default(sysattr.Sys)
+		if err != nil {
+			return nil, err
+		}
+	}
+	sysattr.Files = make([]uintptr, 0, len(attr.Files))
+	for _, f := range attr.Files {
+		sysattr.Files = append(sysattr.Files, f.Fd())
+	}
+
+	pid, h, e := syscall.StartProcess(name, argv, sysattr)
+
+	// Make sure we don't run the finalizers of attr.Files.
+	runtime.KeepAlive(attr)
+
+	if e != nil {
+		return nil, &PathError{Op: "fork/exec", Path: name, Err: e}
+	}
+
+	return newProcess(pid, h), nil
+}
+
+func (p *Process) kill() error {
+	return p.Signal(Kill)
+}
+
+// ProcessState stores information about a process, as reported by Wait.
+type ProcessState struct {
+	pid    int                // The process's id.
+	status syscall.WaitStatus // System-dependent status info.
+	rusage *syscall.Rusage
+}
+
+// Pid returns the process id of the exited process.
+func (p *ProcessState) Pid() int {
+	return p.pid
+}
+
+func (p *ProcessState) exited() bool {
+	return p.status.Exited()
+}
+
+func (p *ProcessState) success() bool {
+	return p.status.ExitStatus() == 0
+}
+
+func (p *ProcessState) sys() any {
+	return p.status
+}
+
+func (p *ProcessState) sysUsage() any {
+	return p.rusage
+}
+
+func (p *ProcessState) String() string {
+	if p == nil {
+		return "<nil>"
+	}
+	status := p.Sys().(syscall.WaitStatus)
+	res := ""
+	switch {
+	case status.Exited():
+		code := status.ExitStatus()
+		if runtime.GOOS == "windows" && uint(code) >= 1<<16 { // windows uses large hex numbers
+			res = "exit status " + uitox(uint(code))
+		} else { // unix systems use small decimal integers
+			res = "exit status " + itoa.Itoa(code) // unix
+		}
+	case status.Signaled():
+		res = "signal: " + status.Signal().String()
+	case status.Stopped():
+		res = "stop signal: " + status.StopSignal().String()
+		if status.StopSignal() == syscall.SIGTRAP && status.TrapCause() != 0 {
+			res += " (trap " + itoa.Itoa(status.TrapCause()) + ")"
+		}
+	case status.Continued():
+		res = "continued"
+	}
+	if status.CoreDump() {
+		res += " (core dumped)"
+	}
+	return res
+}
+
+// ExitCode returns the exit code of the exited process, or -1
+// if the process hasn't exited or was terminated by a signal.
+func (p *ProcessState) ExitCode() int {
+	// return -1 if the process hasn't started.
+	if p == nil {
+		return -1
+	}
+	return p.status.ExitStatus()
+}
diff --git a/contrib/go/_std_1.19/src/os/exec_unix.go b/contrib/go/_std_1.19/src/os/exec_unix.go
new file mode 100644
index 0000000000..90a4a61222
--- /dev/null
+++ b/contrib/go/_std_1.19/src/os/exec_unix.go
@@ -0,0 +1,106 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm)
+
+package os
+
+import (
+	"errors"
+	"runtime"
+	"syscall"
+	"time"
+)
+
+func (p *Process) wait() (ps *ProcessState, err error) {
+	if p.Pid == -1 {
+		return nil, syscall.EINVAL
+	}
+
+	// If we can block until Wait4 will succeed immediately, do so.
+	ready, err := p.blockUntilWaitable()
+	if err != nil {
+		return nil, err
+	}
+	if ready {
+		// Mark the process done now, before the call to Wait4,
+		// so that Process.signal will not send a signal.
+		p.setDone()
+		// Acquire a write lock on sigMu to wait for any
+		// active call to the signal method to complete.
+		p.sigMu.Lock()
+		p.sigMu.Unlock()
+	}
+
+	var (
+		status syscall.WaitStatus
+		rusage syscall.Rusage
+		pid1   int
+		e      error
+	)
+	for {
+		pid1, e = syscall.Wait4(p.Pid, &status, 0, &rusage)
+		if e != syscall.EINTR {
+			break
+		}
+	}
+	if e != nil {
+		return nil, NewSyscallError("wait", e)
+	}
+	if pid1 != 0 {
+		p.setDone()
+	}
+	ps = &ProcessState{
+		pid:    pid1,
+		status: status,
+		rusage: &rusage,
+	}
+	return ps, nil
+}
+
+func (p *Process) signal(sig Signal) error {
+	if p.Pid == -1 {
+		return errors.New("os: process already released")
+	}
+	if p.Pid == 0 {
+		return errors.New("os: process not initialized")
+	}
+	p.sigMu.RLock()
+	defer p.sigMu.RUnlock()
+	if p.done() {
+		return ErrProcessDone
+	}
+	s, ok := sig.(syscall.Signal)
+	if !ok {
+		return errors.New("os: unsupported signal type")
+	}
+	if e := syscall.Kill(p.Pid, s); e != nil {
+		if e == syscall.ESRCH {
+			return ErrProcessDone
+		}
+		return e
+	}
+	return nil
+}
+
+func (p *Process) release() error {
+	// NOOP for unix.
+	p.Pid = -1
+	// no need for a finalizer anymore
+	runtime.SetFinalizer(p, nil)
+	return nil
+}
+
+func findProcess(pid int) (p *Process, err error) {
+	// NOOP for unix.
+	return newProcess(pid, 0), nil
+}
+
+func (p *ProcessState) userTime() time.Duration {
+	return time.Duration(p.rusage.Utime.Nano()) * time.Nanosecond
+}
+
+func (p *ProcessState) systemTime() time.Duration {
+	return time.Duration(p.rusage.Stime.Nano()) * time.Nanosecond
+}
diff --git a/contrib/go/_std_1.18/src/os/executable.go b/contrib/go/_std_1.19/src/os/executable.go
index cc3134af1c..cc3134af1c 100644
--- a/contrib/go/_std_1.18/src/os/executable.go
+++ b/contrib/go/_std_1.19/src/os/executable.go
diff --git a/contrib/go/_std_1.18/src/os/executable_darwin.go b/contrib/go/_std_1.19/src/os/executable_darwin.go
index dae9f4ee18..dae9f4ee18 100644
--- a/contrib/go/_std_1.18/src/os/executable_darwin.go
+++ b/contrib/go/_std_1.19/src/os/executable_darwin.go
diff --git a/contrib/go/_std_1.18/src/os/executable_procfs.go b/contrib/go/_std_1.19/src/os/executable_procfs.go
index 18348eab91..18348eab91 100644
--- a/contrib/go/_std_1.18/src/os/executable_procfs.go
+++ b/contrib/go/_std_1.19/src/os/executable_procfs.go
diff --git a/contrib/go/_std_1.19/src/os/file.go b/contrib/go/_std_1.19/src/os/file.go
new file mode 100644
index 0000000000..9f388921ae
--- /dev/null
+++ b/contrib/go/_std_1.19/src/os/file.go
@@ -0,0 +1,726 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package os provides a platform-independent interface to operating system
+// functionality. The design is Unix-like, although the error handling is
+// Go-like; failing calls return values of type error rather than error numbers.
+// Often, more information is available within the error. For example,
+// if a call that takes a file name fails, such as Open or Stat, the error
+// will include the failing file name when printed and will be of type
+// *PathError, which may be unpacked for more information.
+//
+// The os interface is intended to be uniform across all operating systems.
+// Features not generally available appear in the system-specific package syscall.
+//
+// Here is a simple example, opening a file and reading some of it.
+//
+//	file, err := os.Open("file.go") // For read access.
+//	if err != nil {
+//		log.Fatal(err)
+//	}
+//
+// If the open fails, the error string will be self-explanatory, like
+//
+//	open file.go: no such file or directory
+//
+// The file's data can then be read into a slice of bytes. Read and
+// Write take their byte counts from the length of the argument slice.
+//
+//	data := make([]byte, 100)
+//	count, err := file.Read(data)
+//	if err != nil {
+//		log.Fatal(err)
+//	}
+//	fmt.Printf("read %d bytes: %q\n", count, data[:count])
+//
+// Note: The maximum number of concurrent operations on a File may be limited by
+// the OS or the system. The number should be high, but exceeding it may degrade
+// performance or cause other issues.
+package os
+
+import (
+	"errors"
+	"internal/poll"
+	"internal/testlog"
+	"internal/unsafeheader"
+	"io"
+	"io/fs"
+	"runtime"
+	"syscall"
+	"time"
+	"unsafe"
+)
+
+// Name returns the name of the file as presented to Open.
+func (f *File) Name() string { return f.name }
+
+// Stdin, Stdout, and Stderr are open Files pointing to the standard input,
+// standard output, and standard error file descriptors.
+//
+// Note that the Go runtime writes to standard error for panics and crashes;
+// closing Stderr may cause those messages to go elsewhere, perhaps
+// to a file opened later.
+var (
+	Stdin  = NewFile(uintptr(syscall.Stdin), "/dev/stdin")
+	Stdout = NewFile(uintptr(syscall.Stdout), "/dev/stdout")
+	Stderr = NewFile(uintptr(syscall.Stderr), "/dev/stderr")
+)
+
+// Flags to OpenFile wrapping those of the underlying system. Not all
+// flags may be implemented on a given system.
+const (
+	// Exactly one of O_RDONLY, O_WRONLY, or O_RDWR must be specified.
+	O_RDONLY int = syscall.O_RDONLY // open the file read-only.
+	O_WRONLY int = syscall.O_WRONLY // open the file write-only.
+	O_RDWR   int = syscall.O_RDWR   // open the file read-write.
+	// The remaining values may be or'ed in to control behavior.
+	O_APPEND int = syscall.O_APPEND // append data to the file when writing.
+	O_CREATE int = syscall.O_CREAT  // create a new file if none exists.
+	O_EXCL   int = syscall.O_EXCL   // used with O_CREATE, file must not exist.
+	O_SYNC   int = syscall.O_SYNC   // open for synchronous I/O.
+	O_TRUNC  int = syscall.O_TRUNC  // truncate regular writable file when opened.
+)
+
+// Seek whence values.
+//
+// Deprecated: Use io.SeekStart, io.SeekCurrent, and io.SeekEnd.
+const (
+	SEEK_SET int = 0 // seek relative to the origin of the file
+	SEEK_CUR int = 1 // seek relative to the current offset
+	SEEK_END int = 2 // seek relative to the end
+)
+
+// LinkError records an error during a link or symlink or rename
+// system call and the paths that caused it.
+type LinkError struct {
+	Op  string
+	Old string
+	New string
+	Err error
+}
+
+func (e *LinkError) Error() string {
+	return e.Op + " " + e.Old + " " + e.New + ": " + e.Err.Error()
+}
+
+func (e *LinkError) Unwrap() error {
+	return e.Err
+}
+
+// Read reads up to len(b) bytes from the File and stores them in b.
+// It returns the number of bytes read and any error encountered.
+// At end of file, Read returns 0, io.EOF.
+func (f *File) Read(b []byte) (n int, err error) {
+	if err := f.checkValid("read"); err != nil {
+		return 0, err
+	}
+	n, e := f.read(b)
+	return n, f.wrapErr("read", e)
+}
+
+// ReadAt reads len(b) bytes from the File starting at byte offset off.
+// It returns the number of bytes read and the error, if any.
+// ReadAt always returns a non-nil error when n < len(b).
+// At end of file, that error is io.EOF.
+func (f *File) ReadAt(b []byte, off int64) (n int, err error) {
+	if err := f.checkValid("read"); err != nil {
+		return 0, err
+	}
+
+	if off < 0 {
+		return 0, &PathError{Op: "readat", Path: f.name, Err: errors.New("negative offset")}
+	}
+
+	for len(b) > 0 {
+		m, e := f.pread(b, off)
+		if e != nil {
+			err = f.wrapErr("read", e)
+			break
+		}
+		n += m
+		b = b[m:]
+		off += int64(m)
+	}
+	return
+}
+
+// ReadFrom implements io.ReaderFrom.
+func (f *File) ReadFrom(r io.Reader) (n int64, err error) {
+	if err := f.checkValid("write"); err != nil {
+		return 0, err
+	}
+	n, handled, e := f.readFrom(r)
+	if !handled {
+		return genericReadFrom(f, r) // without wrapping
+	}
+	return n, f.wrapErr("write", e)
+}
+
+func genericReadFrom(f *File, r io.Reader) (int64, error) {
+	return io.Copy(onlyWriter{f}, r)
+}
+
+type onlyWriter struct {
+	io.Writer
+}
+
+// Write writes len(b) bytes from b to the File.
+// It returns the number of bytes written and an error, if any.
+// Write returns a non-nil error when n != len(b).
+func (f *File) Write(b []byte) (n int, err error) {
+	if err := f.checkValid("write"); err != nil {
+		return 0, err
+	}
+	n, e := f.write(b)
+	if n < 0 {
+		n = 0
+	}
+	if n != len(b) {
+		err = io.ErrShortWrite
+	}
+
+	epipecheck(f, e)
+
+	if e != nil {
+		err = f.wrapErr("write", e)
+	}
+
+	return n, err
+}
+
+var errWriteAtInAppendMode = errors.New("os: invalid use of WriteAt on file opened with O_APPEND")
+
+// WriteAt writes len(b) bytes to the File starting at byte offset off.
+// It returns the number of bytes written and an error, if any.
+// WriteAt returns a non-nil error when n != len(b).
+//
+// If file was opened with the O_APPEND flag, WriteAt returns an error.
+func (f *File) WriteAt(b []byte, off int64) (n int, err error) {
+	if err := f.checkValid("write"); err != nil {
+		return 0, err
+	}
+	if f.appendMode {
+		return 0, errWriteAtInAppendMode
+	}
+
+	if off < 0 {
+		return 0, &PathError{Op: "writeat", Path: f.name, Err: errors.New("negative offset")}
+	}
+
+	for len(b) > 0 {
+		m, e := f.pwrite(b, off)
+		if e != nil {
+			err = f.wrapErr("write", e)
+			break
+		}
+		n += m
+		b = b[m:]
+		off += int64(m)
+	}
+	return
+}
+
+// Seek sets the offset for the next Read or Write on file to offset, interpreted
+// according to whence: 0 means relative to the origin of the file, 1 means
+// relative to the current offset, and 2 means relative to the end.
+// It returns the new offset and an error, if any.
+// The behavior of Seek on a file opened with O_APPEND is not specified.
+//
+// If f is a directory, the behavior of Seek varies by operating
+// system; you can seek to the beginning of the directory on Unix-like
+// operating systems, but not on Windows.
+func (f *File) Seek(offset int64, whence int) (ret int64, err error) {
+	if err := f.checkValid("seek"); err != nil {
+		return 0, err
+	}
+	r, e := f.seek(offset, whence)
+	if e == nil && f.dirinfo != nil && r != 0 {
+		e = syscall.EISDIR
+	}
+	if e != nil {
+		return 0, f.wrapErr("seek", e)
+	}
+	return r, nil
+}
+
+// WriteString is like Write, but writes the contents of string s rather than
+// a slice of bytes.
+func (f *File) WriteString(s string) (n int, err error) {
+	var b []byte
+	hdr := (*unsafeheader.Slice)(unsafe.Pointer(&b))
+	hdr.Data = (*unsafeheader.String)(unsafe.Pointer(&s)).Data
+	hdr.Cap = len(s)
+	hdr.Len = len(s)
+	return f.Write(b)
+}
+
+// Mkdir creates a new directory with the specified name and permission
+// bits (before umask).
+// If there is an error, it will be of type *PathError.
+func Mkdir(name string, perm FileMode) error {
+	if runtime.GOOS == "windows" && isWindowsNulName(name) {
+		return &PathError{Op: "mkdir", Path: name, Err: syscall.ENOTDIR}
+	}
+	longName := fixLongPath(name)
+	e := ignoringEINTR(func() error {
+		return syscall.Mkdir(longName, syscallMode(perm))
+	})
+
+	if e != nil {
+		return &PathError{Op: "mkdir", Path: name, Err: e}
+	}
+
+	// mkdir(2) itself won't handle the sticky bit on *BSD and Solaris
+	if !supportsCreateWithStickyBit && perm&ModeSticky != 0 {
+		e = setStickyBit(name)
+
+		if e != nil {
+			Remove(name)
+			return e
+		}
+	}
+
+	return nil
+}
+
+// setStickyBit adds ModeSticky to the permission bits of path, non atomic.
+func setStickyBit(name string) error {
+	fi, err := Stat(name)
+	if err != nil {
+		return err
+	}
+	return Chmod(name, fi.Mode()|ModeSticky)
+}
+
+// Chdir changes the current working directory to the named directory.
+// If there is an error, it will be of type *PathError.
+func Chdir(dir string) error {
+	if e := syscall.Chdir(dir); e != nil {
+		testlog.Open(dir) // observe likely non-existent directory
+		return &PathError{Op: "chdir", Path: dir, Err: e}
+	}
+	if log := testlog.Logger(); log != nil {
+		wd, err := Getwd()
+		if err == nil {
+			log.Chdir(wd)
+		}
+	}
+	return nil
+}
+
+// Open opens the named file for reading. If successful, methods on
+// the returned file can be used for reading; the associated file
+// descriptor has mode O_RDONLY.
+// If there is an error, it will be of type *PathError.
+func Open(name string) (*File, error) {
+	return OpenFile(name, O_RDONLY, 0)
+}
+
+// Create creates or truncates the named file. If the file already exists,
+// it is truncated. If the file does not exist, it is created with mode 0666
+// (before umask). If successful, methods on the returned File can
+// be used for I/O; the associated file descriptor has mode O_RDWR.
+// If there is an error, it will be of type *PathError.
+func Create(name string) (*File, error) {
+	return OpenFile(name, O_RDWR|O_CREATE|O_TRUNC, 0666)
+}
+
+// OpenFile is the generalized open call; most users will use Open
+// or Create instead. It opens the named file with specified flag
+// (O_RDONLY etc.). If the file does not exist, and the O_CREATE flag
+// is passed, it is created with mode perm (before umask). If successful,
+// methods on the returned File can be used for I/O.
+// If there is an error, it will be of type *PathError.
+func OpenFile(name string, flag int, perm FileMode) (*File, error) {
+	testlog.Open(name)
+	f, err := openFileNolog(name, flag, perm)
+	if err != nil {
+		return nil, err
+	}
+	f.appendMode = flag&O_APPEND != 0
+
+	return f, nil
+}
+
+// lstat is overridden in tests.
+var lstat = Lstat
+
+// Rename renames (moves) oldpath to newpath.
+// If newpath already exists and is not a directory, Rename replaces it.
+// OS-specific restrictions may apply when oldpath and newpath are in different directories.
+// If there is an error, it will be of type *LinkError.
+func Rename(oldpath, newpath string) error {
+	return rename(oldpath, newpath)
+}
+
+// Many functions in package syscall return a count of -1 instead of 0.
+// Using fixCount(call()) instead of call() corrects the count.
+func fixCount(n int, err error) (int, error) {
+	if n < 0 {
+		n = 0
+	}
+	return n, err
+}
+
+// wrapErr wraps an error that occurred during an operation on an open file.
+// It passes io.EOF through unchanged, otherwise converts
+// poll.ErrFileClosing to ErrClosed and wraps the error in a PathError.
+func (f *File) wrapErr(op string, err error) error {
+	if err == nil || err == io.EOF {
+		return err
+	}
+	if err == poll.ErrFileClosing {
+		err = ErrClosed
+	}
+	return &PathError{Op: op, Path: f.name, Err: err}
+}
+
+// TempDir returns the default directory to use for temporary files.
+//
+// On Unix systems, it returns $TMPDIR if non-empty, else /tmp.
+// On Windows, it uses GetTempPath, returning the first non-empty
+// value from %TMP%, %TEMP%, %USERPROFILE%, or the Windows directory.
+// On Plan 9, it returns /tmp.
+//
+// The directory is neither guaranteed to exist nor have accessible
+// permissions.
+func TempDir() string {
+	return tempDir()
+}
+
+// UserCacheDir returns the default root directory to use for user-specific
+// cached data. Users should create their own application-specific subdirectory
+// within this one and use that.
+//
+// On Unix systems, it returns $XDG_CACHE_HOME as specified by
+// https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html if
+// non-empty, else $HOME/.cache.
+// On Darwin, it returns $HOME/Library/Caches.
+// On Windows, it returns %LocalAppData%.
+// On Plan 9, it returns $home/lib/cache.
+//
+// If the location cannot be determined (for example, $HOME is not defined),
+// then it will return an error.
+func UserCacheDir() (string, error) {
+	var dir string
+
+	switch runtime.GOOS {
+	case "windows":
+		dir = Getenv("LocalAppData")
+		if dir == "" {
+			return "", errors.New("%LocalAppData% is not defined")
+		}
+
+	case "darwin", "ios":
+		dir = Getenv("HOME")
+		if dir == "" {
+			return "", errors.New("$HOME is not defined")
+		}
+		dir += "/Library/Caches"
+
+	case "plan9":
+		dir = Getenv("home")
+		if dir == "" {
+			return "", errors.New("$home is not defined")
+		}
+		dir += "/lib/cache"
+
+	default: // Unix
+		dir = Getenv("XDG_CACHE_HOME")
+		if dir == "" {
+			dir = Getenv("HOME")
+			if dir == "" {
+				return "", errors.New("neither $XDG_CACHE_HOME nor $HOME are defined")
+			}
+			dir += "/.cache"
+		}
+	}
+
+	return dir, nil
+}
+
+// UserConfigDir returns the default root directory to use for user-specific
+// configuration data. Users should create their own application-specific
+// subdirectory within this one and use that.
+//
+// On Unix systems, it returns $XDG_CONFIG_HOME as specified by
+// https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html if
+// non-empty, else $HOME/.config.
+// On Darwin, it returns $HOME/Library/Application Support.
+// On Windows, it returns %AppData%.
+// On Plan 9, it returns $home/lib.
+//
+// If the location cannot be determined (for example, $HOME is not defined),
+// then it will return an error.
+func UserConfigDir() (string, error) {
+	var dir string
+
+	switch runtime.GOOS {
+	case "windows":
+		dir = Getenv("AppData")
+		if dir == "" {
+			return "", errors.New("%AppData% is not defined")
+		}
+
+	case "darwin", "ios":
+		dir = Getenv("HOME")
+		if dir == "" {
+			return "", errors.New("$HOME is not defined")
+		}
+		dir += "/Library/Application Support"
+
+	case "plan9":
+		dir = Getenv("home")
+		if dir == "" {
+			return "", errors.New("$home is not defined")
+		}
+		dir += "/lib"
+
+	default: // Unix
+		dir = Getenv("XDG_CONFIG_HOME")
+		if dir == "" {
+			dir = Getenv("HOME")
+			if dir == "" {
+				return "", errors.New("neither $XDG_CONFIG_HOME nor $HOME are defined")
+			}
+			dir += "/.config"
+		}
+	}
+
+	return dir, nil
+}
+
+// UserHomeDir returns the current user's home directory.
+//
+// On Unix, including macOS, it returns the $HOME environment variable.
+// On Windows, it returns %USERPROFILE%.
+// On Plan 9, it returns the $home environment variable.
+func UserHomeDir() (string, error) {
+	env, enverr := "HOME", "$HOME"
+	switch runtime.GOOS {
+	case "windows":
+		env, enverr = "USERPROFILE", "%userprofile%"
+	case "plan9":
+		env, enverr = "home", "$home"
+	}
+	if v := Getenv(env); v != "" {
+		return v, nil
+	}
+	// On some geese the home directory is not always defined.
+	switch runtime.GOOS {
+	case "android":
+		return "/sdcard", nil
+	case "ios":
+		return "/", nil
+	}
+	return "", errors.New(enverr + " is not defined")
+}
+
+// Chmod changes the mode of the named file to mode.
+// If the file is a symbolic link, it changes the mode of the link's target.
+// If there is an error, it will be of type *PathError.
+//
+// A different subset of the mode bits are used, depending on the
+// operating system.
+//
+// On Unix, the mode's permission bits, ModeSetuid, ModeSetgid, and
+// ModeSticky are used.
+//
+// On Windows, only the 0200 bit (owner writable) of mode is used; it
+// controls whether the file's read-only attribute is set or cleared.
+// The other bits are currently unused. For compatibility with Go 1.12
+// and earlier, use a non-zero mode. Use mode 0400 for a read-only
+// file and 0600 for a readable+writable file.
+//
+// On Plan 9, the mode's permission bits, ModeAppend, ModeExclusive,
+// and ModeTemporary are used.
+func Chmod(name string, mode FileMode) error { return chmod(name, mode) }
+
+// Chmod changes the mode of the file to mode.
+// If there is an error, it will be of type *PathError.
+func (f *File) Chmod(mode FileMode) error { return f.chmod(mode) }
+
+// SetDeadline sets the read and write deadlines for a File.
+// It is equivalent to calling both SetReadDeadline and SetWriteDeadline.
+//
+// Only some kinds of files support setting a deadline. Calls to SetDeadline
+// for files that do not support deadlines will return ErrNoDeadline.
+// On most systems ordinary files do not support deadlines, but pipes do.
+//
+// A deadline is an absolute time after which I/O operations fail with an
+// error instead of blocking. The deadline applies to all future and pending
+// I/O, not just the immediately following call to Read or Write.
+// After a deadline has been exceeded, the connection can be refreshed
+// by setting a deadline in the future.
+//
+// If the deadline is exceeded a call to Read or Write or to other I/O
+// methods will return an error that wraps ErrDeadlineExceeded.
+// This can be tested using errors.Is(err, os.ErrDeadlineExceeded).
+// That error implements the Timeout method, and calling the Timeout
+// method will return true, but there are other possible errors for which
+// the Timeout will return true even if the deadline has not been exceeded.
+//
+// An idle timeout can be implemented by repeatedly extending
+// the deadline after successful Read or Write calls.
+//
+// A zero value for t means I/O operations will not time out.
+func (f *File) SetDeadline(t time.Time) error {
+	return f.setDeadline(t)
+}
+
+// SetReadDeadline sets the deadline for future Read calls and any
+// currently-blocked Read call.
+// A zero value for t means Read will not time out.
+// Not all files support setting deadlines; see SetDeadline.
+func (f *File) SetReadDeadline(t time.Time) error {
+	return f.setReadDeadline(t)
+}
+
+// SetWriteDeadline sets the deadline for any future Write calls and any
+// currently-blocked Write call.
+// Even if Write times out, it may return n > 0, indicating that
+// some of the data was successfully written.
+// A zero value for t means Write will not time out.
+// Not all files support setting deadlines; see SetDeadline.
+func (f *File) SetWriteDeadline(t time.Time) error {
+	return f.setWriteDeadline(t)
+}
+
+// SyscallConn returns a raw file.
+// This implements the syscall.Conn interface.
+func (f *File) SyscallConn() (syscall.RawConn, error) {
+	if err := f.checkValid("SyscallConn"); err != nil {
+		return nil, err
+	}
+	return newRawConn(f)
+}
+
+// isWindowsNulName reports whether name is os.DevNull ('NUL') on Windows.
+// True is returned if name is 'NUL' whatever the case.
+func isWindowsNulName(name string) bool {
+	if len(name) != 3 {
+		return false
+	}
+	if name[0] != 'n' && name[0] != 'N' {
+		return false
+	}
+	if name[1] != 'u' && name[1] != 'U' {
+		return false
+	}
+	if name[2] != 'l' && name[2] != 'L' {
+		return false
+	}
+	return true
+}
+
+// DirFS returns a file system (an fs.FS) for the tree of files rooted at the directory dir.
+//
+// Note that DirFS("/prefix") only guarantees that the Open calls it makes to the
+// operating system will begin with "/prefix": DirFS("/prefix").Open("file") is the
+// same as os.Open("/prefix/file"). So if /prefix/file is a symbolic link pointing outside
+// the /prefix tree, then using DirFS does not stop the access any more than using
+// os.Open does. Additionally, the root of the fs.FS returned for a relative path,
+// DirFS("prefix"), will be affected by later calls to Chdir. DirFS is therefore not
+// a general substitute for a chroot-style security mechanism when the directory tree
+// contains arbitrary content.
+//
+// The result implements fs.StatFS.
+func DirFS(dir string) fs.FS {
+	return dirFS(dir)
+}
+
+func containsAny(s, chars string) bool {
+	for i := 0; i < len(s); i++ {
+		for j := 0; j < len(chars); j++ {
+			if s[i] == chars[j] {
+				return true
+			}
+		}
+	}
+	return false
+}
+
+type dirFS string
+
+func (dir dirFS) Open(name string) (fs.File, error) {
+	if !fs.ValidPath(name) || runtime.GOOS == "windows" && containsAny(name, `\:`) {
+		return nil, &PathError{Op: "open", Path: name, Err: ErrInvalid}
+	}
+	f, err := Open(string(dir) + "/" + name)
+	if err != nil {
+		return nil, err // nil fs.File
+	}
+	return f, nil
+}
+
+func (dir dirFS) Stat(name string) (fs.FileInfo, error) {
+	if !fs.ValidPath(name) || runtime.GOOS == "windows" && containsAny(name, `\:`) {
+		return nil, &PathError{Op: "stat", Path: name, Err: ErrInvalid}
+	}
+	f, err := Stat(string(dir) + "/" + name)
+	if err != nil {
+		return nil, err
+	}
+	return f, nil
+}
+
+// ReadFile reads the named file and returns the contents.
+// A successful call returns err == nil, not err == EOF.
+// Because ReadFile reads the whole file, it does not treat an EOF from Read
+// as an error to be reported.
+func ReadFile(name string) ([]byte, error) {
+	f, err := Open(name)
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	var size int
+	if info, err := f.Stat(); err == nil {
+		size64 := info.Size()
+		if int64(int(size64)) == size64 {
+			size = int(size64)
+		}
+	}
+	size++ // one byte for final read at EOF
+
+	// If a file claims a small size, read at least 512 bytes.
+	// In particular, files in Linux's /proc claim size 0 but
+	// then do not work right if read in small pieces,
+	// so an initial read of 1 byte would not work correctly.
+	if size < 512 {
+		size = 512
+	}
+
+	data := make([]byte, 0, size)
+	for {
+		if len(data) >= cap(data) {
+			d := append(data[:cap(data)], 0)
+			data = d[:len(data)]
+		}
+		n, err := f.Read(data[len(data):cap(data)])
+		data = data[:len(data)+n]
+		if err != nil {
+			if err == io.EOF {
+				err = nil
+			}
+			return data, err
+		}
+	}
+}
+
+// WriteFile writes data to the named file, creating it if necessary.
+// If the file does not exist, WriteFile creates it with permissions perm (before umask);
+// otherwise WriteFile truncates it before writing, without changing permissions.
+func WriteFile(name string, data []byte, perm FileMode) error {
+	f, err := OpenFile(name, O_WRONLY|O_CREATE|O_TRUNC, perm)
+	if err != nil {
+		return err
+	}
+	_, err = f.Write(data)
+	if err1 := f.Close(); err1 != nil && err == nil {
+		err = err1
+	}
+	return err
+}
diff --git a/contrib/go/_std_1.19/src/os/file_posix.go b/contrib/go/_std_1.19/src/os/file_posix.go
new file mode 100644
index 0000000000..c6d18ffeb6
--- /dev/null
+++ b/contrib/go/_std_1.19/src/os/file_posix.go
@@ -0,0 +1,250 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm) || windows
+
+package os
+
+import (
+	"runtime"
+	"syscall"
+	"time"
+)
+
+func sigpipe() // implemented in package runtime
+
+// Close closes the File, rendering it unusable for I/O.
+// On files that support SetDeadline, any pending I/O operations will
+// be canceled and return immediately with an ErrClosed error.
+// Close will return an error if it has already been called.
+func (f *File) Close() error {
+	if f == nil {
+		return ErrInvalid
+	}
+	return f.file.close()
+}
+
+// read reads up to len(b) bytes from the File.
+// It returns the number of bytes read and an error, if any.
+func (f *File) read(b []byte) (n int, err error) {
+	n, err = f.pfd.Read(b)
+	runtime.KeepAlive(f)
+	return n, err
+}
+
+// pread reads len(b) bytes from the File starting at byte offset off.
+// It returns the number of bytes read and the error, if any.
+// EOF is signaled by a zero count with err set to nil.
+func (f *File) pread(b []byte, off int64) (n int, err error) {
+	n, err = f.pfd.Pread(b, off)
+	runtime.KeepAlive(f)
+	return n, err
+}
+
+// write writes len(b) bytes to the File.
+// It returns the number of bytes written and an error, if any.
+func (f *File) write(b []byte) (n int, err error) {
+	n, err = f.pfd.Write(b)
+	runtime.KeepAlive(f)
+	return n, err
+}
+
+// pwrite writes len(b) bytes to the File starting at byte offset off.
+// It returns the number of bytes written and an error, if any.
+func (f *File) pwrite(b []byte, off int64) (n int, err error) {
+	n, err = f.pfd.Pwrite(b, off)
+	runtime.KeepAlive(f)
+	return n, err
+}
+
+// syscallMode returns the syscall-specific mode bits from Go's portable mode bits.
+func syscallMode(i FileMode) (o uint32) {
+	o |= uint32(i.Perm())
+	if i&ModeSetuid != 0 {
+		o |= syscall.S_ISUID
+	}
+	if i&ModeSetgid != 0 {
+		o |= syscall.S_ISGID
+	}
+	if i&ModeSticky != 0 {
+		o |= syscall.S_ISVTX
+	}
+	// No mapping for Go's ModeTemporary (plan9 only).
+	return
+}
+
+// See docs in file.go:Chmod.
+func chmod(name string, mode FileMode) error {
+	longName := fixLongPath(name)
+	e := ignoringEINTR(func() error {
+		return syscall.Chmod(longName, syscallMode(mode))
+	})
+	if e != nil {
+		return &PathError{Op: "chmod", Path: name, Err: e}
+	}
+	return nil
+}
+
+// See docs in file.go:(*File).Chmod.
+func (f *File) chmod(mode FileMode) error {
+	if err := f.checkValid("chmod"); err != nil {
+		return err
+	}
+	if e := f.pfd.Fchmod(syscallMode(mode)); e != nil {
+		return f.wrapErr("chmod", e)
+	}
+	return nil
+}
+
+// Chown changes the numeric uid and gid of the named file.
+// If the file is a symbolic link, it changes the uid and gid of the link's target.
+// A uid or gid of -1 means to not change that value.
+// If there is an error, it will be of type *PathError.
+//
+// On Windows or Plan 9, Chown always returns the syscall.EWINDOWS or
+// EPLAN9 error, wrapped in *PathError.
+func Chown(name string, uid, gid int) error {
+	e := ignoringEINTR(func() error {
+		return syscall.Chown(name, uid, gid)
+	})
+	if e != nil {
+		return &PathError{Op: "chown", Path: name, Err: e}
+	}
+	return nil
+}
+
+// Lchown changes the numeric uid and gid of the named file.
+// If the file is a symbolic link, it changes the uid and gid of the link itself.
+// If there is an error, it will be of type *PathError.
+//
+// On Windows, it always returns the syscall.EWINDOWS error, wrapped
+// in *PathError.
+func Lchown(name string, uid, gid int) error {
+	e := ignoringEINTR(func() error {
+		return syscall.Lchown(name, uid, gid)
+	})
+	if e != nil {
+		return &PathError{Op: "lchown", Path: name, Err: e}
+	}
+	return nil
+}
+
+// Chown changes the numeric uid and gid of the named file.
+// If there is an error, it will be of type *PathError.
+//
+// On Windows, it always returns the syscall.EWINDOWS error, wrapped
+// in *PathError.
+func (f *File) Chown(uid, gid int) error {
+	if err := f.checkValid("chown"); err != nil {
+		return err
+	}
+	if e := f.pfd.Fchown(uid, gid); e != nil {
+		return f.wrapErr("chown", e)
+	}
+	return nil
+}
+
+// Truncate changes the size of the file.
+// It does not change the I/O offset.
+// If there is an error, it will be of type *PathError.
+func (f *File) Truncate(size int64) error {
+	if err := f.checkValid("truncate"); err != nil {
+		return err
+	}
+	if e := f.pfd.Ftruncate(size); e != nil {
+		return f.wrapErr("truncate", e)
+	}
+	return nil
+}
+
+// Sync commits the current contents of the file to stable storage.
+// Typically, this means flushing the file system's in-memory copy
+// of recently written data to disk.
+func (f *File) Sync() error {
+	if err := f.checkValid("sync"); err != nil {
+		return err
+	}
+	if e := f.pfd.Fsync(); e != nil {
+		return f.wrapErr("sync", e)
+	}
+	return nil
+}
+
+// Chtimes changes the access and modification times of the named
+// file, similar to the Unix utime() or utimes() functions.
+//
+// The underlying filesystem may truncate or round the values to a
+// less precise time unit.
+// If there is an error, it will be of type *PathError.
+func Chtimes(name string, atime time.Time, mtime time.Time) error {
+	var utimes [2]syscall.Timespec
+	utimes[0] = syscall.NsecToTimespec(atime.UnixNano())
+	utimes[1] = syscall.NsecToTimespec(mtime.UnixNano())
+	if e := syscall.UtimesNano(fixLongPath(name), utimes[0:]); e != nil {
+		return &PathError{Op: "chtimes", Path: name, Err: e}
+	}
+	return nil
+}
+
+// Chdir changes the current working directory to the file,
+// which must be a directory.
+// If there is an error, it will be of type *PathError.
+func (f *File) Chdir() error {
+	if err := f.checkValid("chdir"); err != nil {
+		return err
+	}
+	if e := f.pfd.Fchdir(); e != nil {
+		return f.wrapErr("chdir", e)
+	}
+	return nil
+}
+
+// setDeadline sets the read and write deadline.
+func (f *File) setDeadline(t time.Time) error {
+	if err := f.checkValid("SetDeadline"); err != nil {
+		return err
+	}
+	return f.pfd.SetDeadline(t)
+}
+
+// setReadDeadline sets the read deadline.
+func (f *File) setReadDeadline(t time.Time) error {
+	if err := f.checkValid("SetReadDeadline"); err != nil {
+		return err
+	}
+	return f.pfd.SetReadDeadline(t)
+}
+
+// setWriteDeadline sets the write deadline.
+func (f *File) setWriteDeadline(t time.Time) error {
+	if err := f.checkValid("SetWriteDeadline"); err != nil {
+		return err
+	}
+	return f.pfd.SetWriteDeadline(t)
+}
+
+// checkValid checks whether f is valid for use.
+// If not, it returns an appropriate error, perhaps incorporating the operation name op.
+func (f *File) checkValid(op string) error {
+	if f == nil {
+		return ErrInvalid
+	}
+	return nil
+}
+
+// ignoringEINTR makes a function call and repeats it if it returns an
+// EINTR error. This appears to be required even though we install all
+// signal handlers with SA_RESTART: see #22838, #38033, #38836, #40846.
+// Also #20400 and #36644 are issues in which a signal handler is
+// installed without setting SA_RESTART. None of these are the common case,
+// but there are enough of them that it seems that we can't avoid
+// an EINTR loop.
+func ignoringEINTR(fn func() error) error {
+	for {
+		err := fn()
+		if err != syscall.EINTR {
+			return err
+		}
+	}
+}
diff --git a/contrib/go/_std_1.19/src/os/file_unix.go b/contrib/go/_std_1.19/src/os/file_unix.go
new file mode 100644
index 0000000000..c30a6890de
--- /dev/null
+++ b/contrib/go/_std_1.19/src/os/file_unix.go
@@ -0,0 +1,430 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm)
+
+package os
+
+import (
+	"internal/poll"
+	"internal/syscall/unix"
+	"runtime"
+	"syscall"
+)
+
+// fixLongPath is a noop on non-Windows platforms.
+func fixLongPath(path string) string {
+	return path
+}
+
+func rename(oldname, newname string) error {
+	fi, err := Lstat(newname)
+	if err == nil && fi.IsDir() {
+		// There are two independent errors this function can return:
+		// one for a bad oldname, and one for a bad newname.
+		// At this point we've determined the newname is bad.
+		// But just in case oldname is also bad, prioritize returning
+		// the oldname error because that's what we did historically.
+		// However, if the old name and new name are not the same, yet
+		// they refer to the same file, it implies a case-only
+		// rename on a case-insensitive filesystem, which is ok.
+		if ofi, err := Lstat(oldname); err != nil {
+			if pe, ok := err.(*PathError); ok {
+				err = pe.Err
+			}
+			return &LinkError{"rename", oldname, newname, err}
+		} else if newname == oldname || !SameFile(fi, ofi) {
+			return &LinkError{"rename", oldname, newname, syscall.EEXIST}
+		}
+	}
+	err = ignoringEINTR(func() error {
+		return syscall.Rename(oldname, newname)
+	})
+	if err != nil {
+		return &LinkError{"rename", oldname, newname, err}
+	}
+	return nil
+}
+
+// file is the real representation of *File.
+// The extra level of indirection ensures that no clients of os
+// can overwrite this data, which could cause the finalizer
+// to close the wrong file descriptor.
+type file struct {
+	pfd         poll.FD
+	name        string
+	dirinfo     *dirInfo // nil unless directory being read
+	nonblock    bool     // whether we set nonblocking mode
+	stdoutOrErr bool     // whether this is stdout or stderr
+	appendMode  bool     // whether file is opened for appending
+}
+
+// Fd returns the integer Unix file descriptor referencing the open file.
+// If f is closed, the file descriptor becomes invalid.
+// If f is garbage collected, a finalizer may close the file descriptor,
+// making it invalid; see runtime.SetFinalizer for more information on when
+// a finalizer might be run. On Unix systems this will cause the SetDeadline
+// methods to stop working.
+// Because file descriptors can be reused, the returned file descriptor may
+// only be closed through the Close method of f, or by its finalizer during
+// garbage collection. Otherwise, during garbage collection the finalizer
+// may close an unrelated file descriptor with the same (reused) number.
+//
+// As an alternative, see the f.SyscallConn method.
+func (f *File) Fd() uintptr {
+	if f == nil {
+		return ^(uintptr(0))
+	}
+
+	// If we put the file descriptor into nonblocking mode,
+	// then set it to blocking mode before we return it,
+	// because historically we have always returned a descriptor
+	// opened in blocking mode. The File will continue to work,
+	// but any blocking operation will tie up a thread.
+	if f.nonblock {
+		f.pfd.SetBlocking()
+	}
+
+	return uintptr(f.pfd.Sysfd)
+}
+
+// NewFile returns a new File with the given file descriptor and
+// name. The returned value will be nil if fd is not a valid file
+// descriptor. On Unix systems, if the file descriptor is in
+// non-blocking mode, NewFile will attempt to return a pollable File
+// (one for which the SetDeadline methods work).
+//
+// After passing it to NewFile, fd may become invalid under the same
+// conditions described in the comments of the Fd method, and the same
+// constraints apply.
+func NewFile(fd uintptr, name string) *File {
+	kind := kindNewFile
+	if nb, err := unix.IsNonblock(int(fd)); err == nil && nb {
+		kind = kindNonBlock
+	}
+	return newFile(fd, name, kind)
+}
+
+// newFileKind describes the kind of file to newFile.
+type newFileKind int
+
+const (
+	kindNewFile newFileKind = iota
+	kindOpenFile
+	kindPipe
+	kindNonBlock
+)
+
+// newFile is like NewFile, but if called from OpenFile or Pipe
+// (as passed in the kind parameter) it tries to add the file to
+// the runtime poller.
+func newFile(fd uintptr, name string, kind newFileKind) *File {
+	fdi := int(fd)
+	if fdi < 0 {
+		return nil
+	}
+	f := &File{&file{
+		pfd: poll.FD{
+			Sysfd:         fdi,
+			IsStream:      true,
+			ZeroReadIsEOF: true,
+		},
+		name:        name,
+		stdoutOrErr: fdi == 1 || fdi == 2,
+	}}
+
+	pollable := kind == kindOpenFile || kind == kindPipe || kind == kindNonBlock
+
+	// If the caller passed a non-blocking filedes (kindNonBlock),
+	// we assume they know what they are doing so we allow it to be
+	// used with kqueue.
+	if kind == kindOpenFile {
+		switch runtime.GOOS {
+		case "darwin", "ios", "dragonfly", "freebsd", "netbsd", "openbsd":
+			var st syscall.Stat_t
+			err := ignoringEINTR(func() error {
+				return syscall.Fstat(fdi, &st)
+			})
+			typ := st.Mode & syscall.S_IFMT
+			// Don't try to use kqueue with regular files on *BSDs.
+			// On FreeBSD a regular file is always
+			// reported as ready for writing.
+			// On Dragonfly, NetBSD and OpenBSD the fd is signaled
+			// only once as ready (both read and write).
+			// Issue 19093.
+			// Also don't add directories to the netpoller.
+			if err == nil && (typ == syscall.S_IFREG || typ == syscall.S_IFDIR) {
+				pollable = false
+			}
+
+			// In addition to the behavior described above for regular files,
+			// on Darwin, kqueue does not work properly with fifos:
+			// closing the last writer does not cause a kqueue event
+			// for any readers. See issue #24164.
+			if (runtime.GOOS == "darwin" || runtime.GOOS == "ios") && typ == syscall.S_IFIFO {
+				pollable = false
+			}
+		}
+	}
+
+	if err := f.pfd.Init("file", pollable); err != nil {
+		// An error here indicates a failure to register
+		// with the netpoll system. That can happen for
+		// a file descriptor that is not supported by
+		// epoll/kqueue; for example, disk files on
+		// Linux systems. We assume that any real error
+		// will show up in later I/O.
+	} else if pollable {
+		// We successfully registered with netpoll, so put
+		// the file into nonblocking mode.
+		if err := syscall.SetNonblock(fdi, true); err == nil {
+			f.nonblock = true
+		}
+	}
+
+	runtime.SetFinalizer(f.file, (*file).close)
+	return f
+}
+
+// epipecheck raises SIGPIPE if we get an EPIPE error on standard
+// output or standard error. See the SIGPIPE docs in os/signal, and
+// issue 11845.
+func epipecheck(file *File, e error) {
+	if e == syscall.EPIPE && file.stdoutOrErr {
+		sigpipe()
+	}
+}
+
+// DevNull is the name of the operating system's “null device.”
+// On Unix-like systems, it is "/dev/null"; on Windows, "NUL".
+const DevNull = "/dev/null"
+
+// openFileNolog is the Unix implementation of OpenFile.
+// Changes here should be reflected in openFdAt, if relevant.
+func openFileNolog(name string, flag int, perm FileMode) (*File, error) {
+	setSticky := false
+	if !supportsCreateWithStickyBit && flag&O_CREATE != 0 && perm&ModeSticky != 0 {
+		if _, err := Stat(name); IsNotExist(err) {
+			setSticky = true
+		}
+	}
+
+	var r int
+	for {
+		var e error
+		r, e = syscall.Open(name, flag|syscall.O_CLOEXEC, syscallMode(perm))
+		if e == nil {
+			break
+		}
+
+		// We have to check EINTR here, per issues 11180 and 39237.
+		if e == syscall.EINTR {
+			continue
+		}
+
+		return nil, &PathError{Op: "open", Path: name, Err: e}
+	}
+
+	// open(2) itself won't handle the sticky bit on *BSD and Solaris
+	if setSticky {
+		setStickyBit(name)
+	}
+
+	// There's a race here with fork/exec, which we are
+	// content to live with. See ../syscall/exec_unix.go.
+	if !supportsCloseOnExec {
+		syscall.CloseOnExec(r)
+	}
+
+	return newFile(uintptr(r), name, kindOpenFile), nil
+}
+
+func (file *file) close() error {
+	if file == nil {
+		return syscall.EINVAL
+	}
+	if file.dirinfo != nil {
+		file.dirinfo.close()
+		file.dirinfo = nil
+	}
+	var err error
+	if e := file.pfd.Close(); e != nil {
+		if e == poll.ErrFileClosing {
+			e = ErrClosed
+		}
+		err = &PathError{Op: "close", Path: file.name, Err: e}
+	}
+
+	// no need for a finalizer anymore
+	runtime.SetFinalizer(file, nil)
+	return err
+}
+
+// seek sets the offset for the next Read or Write on file to offset, interpreted
+// according to whence: 0 means relative to the origin of the file, 1 means
+// relative to the current offset, and 2 means relative to the end.
+// It returns the new offset and an error, if any.
+func (f *File) seek(offset int64, whence int) (ret int64, err error) {
+	if f.dirinfo != nil {
+		// Free cached dirinfo, so we allocate a new one if we
+		// access this file as a directory again. See #35767 and #37161.
+		f.dirinfo.close()
+		f.dirinfo = nil
+	}
+	ret, err = f.pfd.Seek(offset, whence)
+	runtime.KeepAlive(f)
+	return ret, err
+}
+
+// Truncate changes the size of the named file.
+// If the file is a symbolic link, it changes the size of the link's target.
+// If there is an error, it will be of type *PathError.
+func Truncate(name string, size int64) error {
+	e := ignoringEINTR(func() error {
+		return syscall.Truncate(name, size)
+	})
+	if e != nil {
+		return &PathError{Op: "truncate", Path: name, Err: e}
+	}
+	return nil
+}
+
+// Remove removes the named file or (empty) directory.
+// If there is an error, it will be of type *PathError.
+func Remove(name string) error {
+	// System call interface forces us to know
+	// whether name is a file or directory.
+	// Try both: it is cheaper on average than
+	// doing a Stat plus the right one.
+	e := ignoringEINTR(func() error {
+		return syscall.Unlink(name)
+	})
+	if e == nil {
+		return nil
+	}
+	e1 := ignoringEINTR(func() error {
+		return syscall.Rmdir(name)
+	})
+	if e1 == nil {
+		return nil
+	}
+
+	// Both failed: figure out which error to return.
+	// OS X and Linux differ on whether unlink(dir)
+	// returns EISDIR, so can't use that. However,
+	// both agree that rmdir(file) returns ENOTDIR,
+	// so we can use that to decide which error is real.
+	// Rmdir might also return ENOTDIR if given a bad
+	// file path, like /etc/passwd/foo, but in that case,
+	// both errors will be ENOTDIR, so it's okay to
+	// use the error from unlink.
+	if e1 != syscall.ENOTDIR {
+		e = e1
+	}
+	return &PathError{Op: "remove", Path: name, Err: e}
+}
+
+func tempDir() string {
+	dir := Getenv("TMPDIR")
+	if dir == "" {
+		if runtime.GOOS == "android" {
+			dir = "/data/local/tmp"
+		} else {
+			dir = "/tmp"
+		}
+	}
+	return dir
+}
+
+// Link creates newname as a hard link to the oldname file.
+// If there is an error, it will be of type *LinkError.
+func Link(oldname, newname string) error {
+	e := ignoringEINTR(func() error {
+		return syscall.Link(oldname, newname)
+	})
+	if e != nil {
+		return &LinkError{"link", oldname, newname, e}
+	}
+	return nil
+}
+
+// Symlink creates newname as a symbolic link to oldname.
+// On Windows, a symlink to a non-existent oldname creates a file symlink;
+// if oldname is later created as a directory the symlink will not work.
+// If there is an error, it will be of type *LinkError.
+func Symlink(oldname, newname string) error {
+	e := ignoringEINTR(func() error {
+		return syscall.Symlink(oldname, newname)
+	})
+	if e != nil {
+		return &LinkError{"symlink", oldname, newname, e}
+	}
+	return nil
+}
+
+// Readlink returns the destination of the named symbolic link.
+// If there is an error, it will be of type *PathError.
+func Readlink(name string) (string, error) {
+	for len := 128; ; len *= 2 {
+		b := make([]byte, len)
+		var (
+			n int
+			e error
+		)
+		for {
+			n, e = fixCount(syscall.Readlink(name, b))
+			if e != syscall.EINTR {
+				break
+			}
+		}
+		// buffer too small
+		if runtime.GOOS == "aix" && e == syscall.ERANGE {
+			continue
+		}
+		if e != nil {
+			return "", &PathError{Op: "readlink", Path: name, Err: e}
+		}
+		if n < len {
+			return string(b[0:n]), nil
+		}
+	}
+}
+
+type unixDirent struct {
+	parent string
+	name   string
+	typ    FileMode
+	info   FileInfo
+}
+
+func (d *unixDirent) Name() string   { return d.name }
+func (d *unixDirent) IsDir() bool    { return d.typ.IsDir() }
+func (d *unixDirent) Type() FileMode { return d.typ }
+
+func (d *unixDirent) Info() (FileInfo, error) {
+	if d.info != nil {
+		return d.info, nil
+	}
+	return lstat(d.parent + "/" + d.name)
+}
+
+func newUnixDirent(parent, name string, typ FileMode) (DirEntry, error) {
+	ude := &unixDirent{
+		parent: parent,
+		name:   name,
+		typ:    typ,
+	}
+	if typ != ^FileMode(0) && !testingForceReadDirLstat {
+		return ude, nil
+	}
+
+	info, err := lstat(parent + "/" + name)
+	if err != nil {
+		return nil, err
+	}
+
+	ude.typ = info.Mode().Type()
+	ude.info = info
+	return ude, nil
+}
diff --git a/contrib/go/_std_1.18/src/os/getwd.go b/contrib/go/_std_1.19/src/os/getwd.go
index 90604cf2f4..90604cf2f4 100644
--- a/contrib/go/_std_1.18/src/os/getwd.go
+++ b/contrib/go/_std_1.19/src/os/getwd.go
diff --git a/contrib/go/_std_1.18/src/os/path.go b/contrib/go/_std_1.19/src/os/path.go
index df87887b9b..df87887b9b 100644
--- a/contrib/go/_std_1.18/src/os/path.go
+++ b/contrib/go/_std_1.19/src/os/path.go
diff --git a/contrib/go/_std_1.19/src/os/path_unix.go b/contrib/go/_std_1.19/src/os/path_unix.go
new file mode 100644
index 0000000000..3c6310a4df
--- /dev/null
+++ b/contrib/go/_std_1.19/src/os/path_unix.go
@@ -0,0 +1,75 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm)
+
+package os
+
+const (
+	PathSeparator     = '/' // OS-specific path separator
+	PathListSeparator = ':' // OS-specific path list separator
+)
+
+// IsPathSeparator reports whether c is a directory separator character.
+func IsPathSeparator(c uint8) bool {
+	return PathSeparator == c
+}
+
+// basename removes trailing slashes and the leading directory name from path name.
+func basename(name string) string {
+	i := len(name) - 1
+	// Remove trailing slashes
+	for ; i > 0 && name[i] == '/'; i-- {
+		name = name[:i]
+	}
+	// Remove leading directory name
+	for i--; i >= 0; i-- {
+		if name[i] == '/' {
+			name = name[i+1:]
+			break
+		}
+	}
+
+	return name
+}
+
+// splitPath returns the base name and parent directory.
+func splitPath(path string) (string, string) {
+	// if no better parent is found, the path is relative from "here"
+	dirname := "."
+
+	// Remove all but one leading slash.
+	for len(path) > 1 && path[0] == '/' && path[1] == '/' {
+		path = path[1:]
+	}
+
+	i := len(path) - 1
+
+	// Remove trailing slashes.
+	for ; i > 0 && path[i] == '/'; i-- {
+		path = path[:i]
+	}
+
+	// if no slashes in path, base is path
+	basename := path
+
+	// Remove leading directory path
+	for i--; i >= 0; i-- {
+		if path[i] == '/' {
+			if i == 0 {
+				dirname = path[:1]
+			} else {
+				dirname = path[:i]
+			}
+			basename = path[i+1:]
+			break
+		}
+	}
+
+	return dirname, basename
+}
+
+func fixRootDirectory(p string) string {
+	return p
+}
diff --git a/contrib/go/_std_1.19/src/os/pipe2_unix.go b/contrib/go/_std_1.19/src/os/pipe2_unix.go
new file mode 100644
index 0000000000..1e2e8ccb67
--- /dev/null
+++ b/contrib/go/_std_1.19/src/os/pipe2_unix.go
@@ -0,0 +1,22 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build dragonfly || freebsd || linux || netbsd || openbsd || solaris
+
+package os
+
+import "syscall"
+
+// Pipe returns a connected pair of Files; reads from r return bytes written to w.
+// It returns the files and an error, if any.
+func Pipe() (r *File, w *File, err error) {
+	var p [2]int
+
+	e := syscall.Pipe2(p[0:], syscall.O_CLOEXEC)
+	if e != nil {
+		return nil, nil, NewSyscallError("pipe2", e)
+	}
+
+	return newFile(uintptr(p[0]), "|0", kindPipe), newFile(uintptr(p[1]), "|1", kindPipe), nil
+}
diff --git a/contrib/go/_std_1.19/src/os/pipe_unix.go b/contrib/go/_std_1.19/src/os/pipe_unix.go
new file mode 100644
index 0000000000..710f77670e
--- /dev/null
+++ b/contrib/go/_std_1.19/src/os/pipe_unix.go
@@ -0,0 +1,28 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build aix || darwin || (js && wasm)
+
+package os
+
+import "syscall"
+
+// Pipe returns a connected pair of Files; reads from r return bytes written to w.
+// It returns the files and an error, if any.
+func Pipe() (r *File, w *File, err error) {
+	var p [2]int
+
+	// See ../syscall/exec.go for description of lock.
+	syscall.ForkLock.RLock()
+	e := syscall.Pipe(p[0:])
+	if e != nil {
+		syscall.ForkLock.RUnlock()
+		return nil, nil, NewSyscallError("pipe", e)
+	}
+	syscall.CloseOnExec(p[0])
+	syscall.CloseOnExec(p[1])
+	syscall.ForkLock.RUnlock()
+
+	return newFile(uintptr(p[0]), "|0", kindPipe), newFile(uintptr(p[1]), "|1", kindPipe), nil
+}
diff --git a/contrib/go/_std_1.18/src/os/proc.go b/contrib/go/_std_1.19/src/os/proc.go
index cbd5a6aad9..cbd5a6aad9 100644
--- a/contrib/go/_std_1.18/src/os/proc.go
+++ b/contrib/go/_std_1.19/src/os/proc.go
diff --git a/contrib/go/_std_1.18/src/os/rawconn.go b/contrib/go/_std_1.19/src/os/rawconn.go
index 14a495d9c0..14a495d9c0 100644
--- a/contrib/go/_std_1.18/src/os/rawconn.go
+++ b/contrib/go/_std_1.19/src/os/rawconn.go
diff --git a/contrib/go/_std_1.18/src/os/readfrom_linux.go b/contrib/go/_std_1.19/src/os/readfrom_linux.go
index 63ea45cf65..63ea45cf65 100644
--- a/contrib/go/_std_1.18/src/os/readfrom_linux.go
+++ b/contrib/go/_std_1.19/src/os/readfrom_linux.go
diff --git a/contrib/go/_std_1.18/src/os/readfrom_stub.go b/contrib/go/_std_1.19/src/os/readfrom_stub.go
index 8b7d5fb8f9..8b7d5fb8f9 100644
--- a/contrib/go/_std_1.18/src/os/readfrom_stub.go
+++ b/contrib/go/_std_1.19/src/os/readfrom_stub.go
diff --git a/contrib/go/_std_1.19/src/os/removeall_at.go b/contrib/go/_std_1.19/src/os/removeall_at.go
new file mode 100644
index 0000000000..8b46152a9e
--- /dev/null
+++ b/contrib/go/_std_1.19/src/os/removeall_at.go
@@ -0,0 +1,192 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix
+
+package os
+
+import (
+	"internal/syscall/unix"
+	"io"
+	"syscall"
+)
+
+func removeAll(path string) error {
+	if path == "" {
+		// fail silently to retain compatibility with previous behavior
+		// of RemoveAll. See issue 28830.
+		return nil
+	}
+
+	// The rmdir system call does not permit removing ".",
+	// so we don't permit it either.
+	if endsWithDot(path) {
+		return &PathError{Op: "RemoveAll", Path: path, Err: syscall.EINVAL}
+	}
+
+	// Simple case: if Remove works, we're done.
+	err := Remove(path)
+	if err == nil || IsNotExist(err) {
+		return nil
+	}
+
+	// RemoveAll recurses by deleting the path base from
+	// its parent directory
+	parentDir, base := splitPath(path)
+
+	parent, err := Open(parentDir)
+	if IsNotExist(err) {
+		// If parent does not exist, base cannot exist. Fail silently
+		return nil
+	}
+	if err != nil {
+		return err
+	}
+	defer parent.Close()
+
+	if err := removeAllFrom(parent, base); err != nil {
+		if pathErr, ok := err.(*PathError); ok {
+			pathErr.Path = parentDir + string(PathSeparator) + pathErr.Path
+			err = pathErr
+		}
+		return err
+	}
+	return nil
+}
+
+func removeAllFrom(parent *File, base string) error {
+	parentFd := int(parent.Fd())
+	// Simple case: if Unlink (aka remove) works, we're done.
+	err := unix.Unlinkat(parentFd, base, 0)
+	if err == nil || IsNotExist(err) {
+		return nil
+	}
+
+	// EISDIR means that we have a directory, and we need to
+	// remove its contents.
+	// EPERM or EACCES means that we don't have write permission on
+	// the parent directory, but this entry might still be a directory
+	// whose contents need to be removed.
+	// Otherwise just return the error.
+	if err != syscall.EISDIR && err != syscall.EPERM && err != syscall.EACCES {
+		return &PathError{Op: "unlinkat", Path: base, Err: err}
+	}
+
+	// Is this a directory we need to recurse into?
+	var statInfo syscall.Stat_t
+	statErr := unix.Fstatat(parentFd, base, &statInfo, unix.AT_SYMLINK_NOFOLLOW)
+	if statErr != nil {
+		if IsNotExist(statErr) {
+			return nil
+		}
+		return &PathError{Op: "fstatat", Path: base, Err: statErr}
+	}
+	if statInfo.Mode&syscall.S_IFMT != syscall.S_IFDIR {
+		// Not a directory; return the error from the unix.Unlinkat.
+		return &PathError{Op: "unlinkat", Path: base, Err: err}
+	}
+
+	// Remove the directory's entries.
+	var recurseErr error
+	for {
+		const reqSize = 1024
+		var respSize int
+
+		// Open the directory to recurse into
+		file, err := openFdAt(parentFd, base)
+		if err != nil {
+			if IsNotExist(err) {
+				return nil
+			}
+			recurseErr = &PathError{Op: "openfdat", Path: base, Err: err}
+			break
+		}
+
+		for {
+			numErr := 0
+
+			names, readErr := file.Readdirnames(reqSize)
+			// Errors other than EOF should stop us from continuing.
+			if readErr != nil && readErr != io.EOF {
+				file.Close()
+				if IsNotExist(readErr) {
+					return nil
+				}
+				return &PathError{Op: "readdirnames", Path: base, Err: readErr}
+			}
+
+			respSize = len(names)
+			for _, name := range names {
+				err := removeAllFrom(file, name)
+				if err != nil {
+					if pathErr, ok := err.(*PathError); ok {
+						pathErr.Path = base + string(PathSeparator) + pathErr.Path
+					}
+					numErr++
+					if recurseErr == nil {
+						recurseErr = err
+					}
+				}
+			}
+
+			// If we can delete any entry, break to start new iteration.
+			// Otherwise, we discard current names, get next entries and try deleting them.
+			if numErr != reqSize {
+				break
+			}
+		}
+
+		// Removing files from the directory may have caused
+		// the OS to reshuffle it. Simply calling Readdirnames
+		// again may skip some entries. The only reliable way
+		// to avoid this is to close and re-open the
+		// directory. See issue 20841.
+		file.Close()
+
+		// Finish when the end of the directory is reached
+		if respSize < reqSize {
+			break
+		}
+	}
+
+	// Remove the directory itself.
+	unlinkError := unix.Unlinkat(parentFd, base, unix.AT_REMOVEDIR)
+	if unlinkError == nil || IsNotExist(unlinkError) {
+		return nil
+	}
+
+	if recurseErr != nil {
+		return recurseErr
+	}
+	return &PathError{Op: "unlinkat", Path: base, Err: unlinkError}
+}
+
+// openFdAt opens path relative to the directory in fd.
+// Other than that this should act like openFileNolog.
+// This acts like openFileNolog rather than OpenFile because
+// we are going to (try to) remove the file.
+// The contents of this file are not relevant for test caching.
+func openFdAt(dirfd int, name string) (*File, error) {
+	var r int
+	for {
+		var e error
+		r, e = unix.Openat(dirfd, name, O_RDONLY|syscall.O_CLOEXEC, 0)
+		if e == nil {
+			break
+		}
+
+		// See comment in openFileNolog.
+		if e == syscall.EINTR {
+			continue
+		}
+
+		return nil, e
+	}
+
+	if !supportsCloseOnExec {
+		syscall.CloseOnExec(r)
+	}
+
+	return newFile(uintptr(r), name, kindOpenFile), nil
+}
diff --git a/contrib/go/_std_1.19/src/os/rlimit.go b/contrib/go/_std_1.19/src/os/rlimit.go
new file mode 100644
index 0000000000..a89414d098
--- /dev/null
+++ b/contrib/go/_std_1.19/src/os/rlimit.go
@@ -0,0 +1,32 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
+
+package os
+
+import "syscall"
+
+// Some systems set an artificially low soft limit on open file count, for compatibility
+// with code that uses select and its hard-coded maximum file descriptor
+// (limited by the size of fd_set).
+//
+// Go does not use select, so it should not be subject to these limits.
+// On some systems the limit is 256, which is very easy to run into,
+// even in simple programs like gofmt when they parallelize walking
+// a file tree.
+//
+// After a long discussion on go.dev/issue/46279, we decided the
+// best approach was for Go to raise the limit unconditionally for itself,
+// and then leave old software to set the limit back as needed.
+// Code that really wants Go to leave the limit alone can set the hard limit,
+// which Go of course has no choice but to respect.
+func init() {
+	var lim syscall.Rlimit
+	if err := syscall.Getrlimit(syscall.RLIMIT_NOFILE, &lim); err == nil && lim.Cur != lim.Max {
+		lim.Cur = lim.Max
+		adjustFileLimit(&lim)
+		syscall.Setrlimit(syscall.RLIMIT_NOFILE, &lim)
+	}
+}
diff --git a/contrib/go/_std_1.19/src/os/rlimit_darwin.go b/contrib/go/_std_1.19/src/os/rlimit_darwin.go
new file mode 100644
index 0000000000..b28982a83a
--- /dev/null
+++ b/contrib/go/_std_1.19/src/os/rlimit_darwin.go
@@ -0,0 +1,22 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build darwin
+
+package os
+
+import "syscall"
+
+// adjustFileLimit adds per-OS limitations on the Rlimit used for RLIMIT_NOFILE. See rlimit.go.
+func adjustFileLimit(lim *syscall.Rlimit) {
+	// On older macOS, setrlimit(RLIMIT_NOFILE, lim) with lim.Cur = infinity fails.
+	// Set to the value of kern.maxfilesperproc instead.
+	n, err := syscall.SysctlUint32("kern.maxfilesperproc")
+	if err != nil {
+		return
+	}
+	if lim.Cur > uint64(n) {
+		lim.Cur = uint64(n)
+	}
+}
diff --git a/contrib/go/_std_1.19/src/os/rlimit_stub.go b/contrib/go/_std_1.19/src/os/rlimit_stub.go
new file mode 100644
index 0000000000..cbe28400c5
--- /dev/null
+++ b/contrib/go/_std_1.19/src/os/rlimit_stub.go
@@ -0,0 +1,12 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build aix || dragonfly || freebsd || linux || netbsd || openbsd || solaris
+
+package os
+
+import "syscall"
+
+// adjustFileLimit adds per-OS limitations on the Rlimit used for RLIMIT_NOFILE. See rlimit.go.
+func adjustFileLimit(lim *syscall.Rlimit) {}
diff --git a/contrib/go/_std_1.18/src/os/stat.go b/contrib/go/_std_1.19/src/os/stat.go
index af66838e3e..af66838e3e 100644
--- a/contrib/go/_std_1.18/src/os/stat.go
+++ b/contrib/go/_std_1.19/src/os/stat.go
diff --git a/contrib/go/_std_1.19/src/os/stat_darwin.go b/contrib/go/_std_1.19/src/os/stat_darwin.go
new file mode 100644
index 0000000000..b92ffd4a0a
--- /dev/null
+++ b/contrib/go/_std_1.19/src/os/stat_darwin.go
@@ -0,0 +1,47 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package os
+
+import (
+	"syscall"
+	"time"
+)
+
+func fillFileStatFromSys(fs *fileStat, name string) {
+	fs.name = basename(name)
+	fs.size = fs.sys.Size
+	fs.modTime = time.Unix(fs.sys.Mtimespec.Unix())
+	fs.mode = FileMode(fs.sys.Mode & 0777)
+	switch fs.sys.Mode & syscall.S_IFMT {
+	case syscall.S_IFBLK, syscall.S_IFWHT:
+		fs.mode |= ModeDevice
+	case syscall.S_IFCHR:
+		fs.mode |= ModeDevice | ModeCharDevice
+	case syscall.S_IFDIR:
+		fs.mode |= ModeDir
+	case syscall.S_IFIFO:
+		fs.mode |= ModeNamedPipe
+	case syscall.S_IFLNK:
+		fs.mode |= ModeSymlink
+	case syscall.S_IFREG:
+		// nothing to do
+	case syscall.S_IFSOCK:
+		fs.mode |= ModeSocket
+	}
+	if fs.sys.Mode&syscall.S_ISGID != 0 {
+		fs.mode |= ModeSetgid
+	}
+	if fs.sys.Mode&syscall.S_ISUID != 0 {
+		fs.mode |= ModeSetuid
+	}
+	if fs.sys.Mode&syscall.S_ISVTX != 0 {
+		fs.mode |= ModeSticky
+	}
+}
+
+// For testing.
+func atime(fi FileInfo) time.Time {
+	return time.Unix(fi.Sys().(*syscall.Stat_t).Atimespec.Unix())
+}
diff --git a/contrib/go/_std_1.19/src/os/stat_linux.go b/contrib/go/_std_1.19/src/os/stat_linux.go
new file mode 100644
index 0000000000..316c26c7ca
--- /dev/null
+++ b/contrib/go/_std_1.19/src/os/stat_linux.go
@@ -0,0 +1,47 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package os
+
+import (
+	"syscall"
+	"time"
+)
+
+func fillFileStatFromSys(fs *fileStat, name string) {
+	fs.name = basename(name)
+	fs.size = fs.sys.Size
+	fs.modTime = time.Unix(fs.sys.Mtim.Unix())
+	fs.mode = FileMode(fs.sys.Mode & 0777)
+	switch fs.sys.Mode & syscall.S_IFMT {
+	case syscall.S_IFBLK:
+		fs.mode |= ModeDevice
+	case syscall.S_IFCHR:
+		fs.mode |= ModeDevice | ModeCharDevice
+	case syscall.S_IFDIR:
+		fs.mode |= ModeDir
+	case syscall.S_IFIFO:
+		fs.mode |= ModeNamedPipe
+	case syscall.S_IFLNK:
+		fs.mode |= ModeSymlink
+	case syscall.S_IFREG:
+		// nothing to do
+	case syscall.S_IFSOCK:
+		fs.mode |= ModeSocket
+	}
+	if fs.sys.Mode&syscall.S_ISGID != 0 {
+		fs.mode |= ModeSetgid
+	}
+	if fs.sys.Mode&syscall.S_ISUID != 0 {
+		fs.mode |= ModeSetuid
+	}
+	if fs.sys.Mode&syscall.S_ISVTX != 0 {
+		fs.mode |= ModeSticky
+	}
+}
+
+// For testing.
+func atime(fi FileInfo) time.Time {
+	return time.Unix(fi.Sys().(*syscall.Stat_t).Atim.Unix())
+}
diff --git a/contrib/go/_std_1.19/src/os/stat_unix.go b/contrib/go/_std_1.19/src/os/stat_unix.go
new file mode 100644
index 0000000000..437afc02b4
--- /dev/null
+++ b/contrib/go/_std_1.19/src/os/stat_unix.go
@@ -0,0 +1,52 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm)
+
+package os
+
+import (
+	"syscall"
+)
+
+// Stat returns the FileInfo structure describing file.
+// If there is an error, it will be of type *PathError.
+func (f *File) Stat() (FileInfo, error) {
+	if f == nil {
+		return nil, ErrInvalid
+	}
+	var fs fileStat
+	err := f.pfd.Fstat(&fs.sys)
+	if err != nil {
+		return nil, &PathError{Op: "stat", Path: f.name, Err: err}
+	}
+	fillFileStatFromSys(&fs, f.name)
+	return &fs, nil
+}
+
+// statNolog stats a file with no test logging.
+func statNolog(name string) (FileInfo, error) {
+	var fs fileStat
+	err := ignoringEINTR(func() error {
+		return syscall.Stat(name, &fs.sys)
+	})
+	if err != nil {
+		return nil, &PathError{Op: "stat", Path: name, Err: err}
+	}
+	fillFileStatFromSys(&fs, name)
+	return &fs, nil
+}
+
+// lstatNolog lstats a file with no test logging.
+func lstatNolog(name string) (FileInfo, error) {
+	var fs fileStat
+	err := ignoringEINTR(func() error {
+		return syscall.Lstat(name, &fs.sys)
+	})
+	if err != nil {
+		return nil, &PathError{Op: "lstat", Path: name, Err: err}
+	}
+	fillFileStatFromSys(&fs, name)
+	return &fs, nil
+}
diff --git a/contrib/go/_std_1.18/src/os/sticky_bsd.go b/contrib/go/_std_1.19/src/os/sticky_bsd.go
index e71daf7c74..e71daf7c74 100644
--- a/contrib/go/_std_1.18/src/os/sticky_bsd.go
+++ b/contrib/go/_std_1.19/src/os/sticky_bsd.go
diff --git a/contrib/go/_std_1.18/src/os/sticky_notbsd.go b/contrib/go/_std_1.19/src/os/sticky_notbsd.go
index 9a87fbde92..9a87fbde92 100644
--- a/contrib/go/_std_1.18/src/os/sticky_notbsd.go
+++ b/contrib/go/_std_1.19/src/os/sticky_notbsd.go
diff --git a/contrib/go/_std_1.18/src/os/str.go b/contrib/go/_std_1.19/src/os/str.go
index 35643e0d2f..35643e0d2f 100644
--- a/contrib/go/_std_1.18/src/os/str.go
+++ b/contrib/go/_std_1.19/src/os/str.go
diff --git a/contrib/go/_std_1.18/src/os/sys.go b/contrib/go/_std_1.19/src/os/sys.go
index 28b0f6bab0..28b0f6bab0 100644
--- a/contrib/go/_std_1.18/src/os/sys.go
+++ b/contrib/go/_std_1.19/src/os/sys.go
diff --git a/contrib/go/_std_1.18/src/os/sys_bsd.go b/contrib/go/_std_1.19/src/os/sys_bsd.go
index e272c24571..e272c24571 100644
--- a/contrib/go/_std_1.18/src/os/sys_bsd.go
+++ b/contrib/go/_std_1.19/src/os/sys_bsd.go
diff --git a/contrib/go/_std_1.18/src/os/sys_linux.go b/contrib/go/_std_1.19/src/os/sys_linux.go
index 36a8a24455..36a8a24455 100644
--- a/contrib/go/_std_1.18/src/os/sys_linux.go
+++ b/contrib/go/_std_1.19/src/os/sys_linux.go
diff --git a/contrib/go/_std_1.19/src/os/sys_unix.go b/contrib/go/_std_1.19/src/os/sys_unix.go
new file mode 100644
index 0000000000..79005c2cbd
--- /dev/null
+++ b/contrib/go/_std_1.19/src/os/sys_unix.go
@@ -0,0 +1,14 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix
+
+package os
+
+// supportsCloseOnExec reports whether the platform supports the
+// O_CLOEXEC flag.
+// On Darwin, the O_CLOEXEC flag was introduced in OS X 10.7 (Darwin 11.0.0).
+// See https://support.apple.com/kb/HT1633.
+// On FreeBSD, the O_CLOEXEC flag was introduced in version 8.3.
+const supportsCloseOnExec = true
diff --git a/contrib/go/_std_1.18/src/os/tempfile.go b/contrib/go/_std_1.19/src/os/tempfile.go
index 3be3d13dfb..3be3d13dfb 100644
--- a/contrib/go/_std_1.18/src/os/tempfile.go
+++ b/contrib/go/_std_1.19/src/os/tempfile.go
diff --git a/contrib/go/_std_1.18/src/os/types.go b/contrib/go/_std_1.19/src/os/types.go
index d8edd98b68..d8edd98b68 100644
--- a/contrib/go/_std_1.18/src/os/types.go
+++ b/contrib/go/_std_1.19/src/os/types.go
diff --git a/contrib/go/_std_1.18/src/os/types_unix.go b/contrib/go/_std_1.19/src/os/types_unix.go
index 1b90a5a141..1b90a5a141 100644
--- a/contrib/go/_std_1.18/src/os/types_unix.go
+++ b/contrib/go/_std_1.19/src/os/types_unix.go
diff --git a/contrib/go/_std_1.18/src/os/wait_unimp.go b/contrib/go/_std_1.19/src/os/wait_unimp.go
index 721b9f9f7e..721b9f9f7e 100644
--- a/contrib/go/_std_1.18/src/os/wait_unimp.go
+++ b/contrib/go/_std_1.19/src/os/wait_unimp.go
diff --git a/contrib/go/_std_1.18/src/os/wait_waitid.go b/contrib/go/_std_1.19/src/os/wait_waitid.go
index c0503b209c..c0503b209c 100644
--- a/contrib/go/_std_1.18/src/os/wait_waitid.go
+++ b/contrib/go/_std_1.19/src/os/wait_waitid.go
diff --git a/contrib/go/_std_1.19/src/path/filepath/match.go b/contrib/go/_std_1.19/src/path/filepath/match.go
new file mode 100644
index 0000000000..b5cc4b8cf3
--- /dev/null
+++ b/contrib/go/_std_1.19/src/path/filepath/match.go
@@ -0,0 +1,369 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package filepath
+
+import (
+	"errors"
+	"os"
+	"runtime"
+	"sort"
+	"strings"
+	"unicode/utf8"
+)
+
+// ErrBadPattern indicates a pattern was malformed.
+var ErrBadPattern = errors.New("syntax error in pattern")
+
+// Match reports whether name matches the shell file name pattern.
+// The pattern syntax is:
+//
+//	pattern:
+//		{ term }
+//	term:
+//		'*'         matches any sequence of non-Separator characters
+//		'?'         matches any single non-Separator character
+//		'[' [ '^' ] { character-range } ']'
+//		            character class (must be non-empty)
+//		c           matches character c (c != '*', '?', '\\', '[')
+//		'\\' c      matches character c
+//
+//	character-range:
+//		c           matches character c (c != '\\', '-', ']')
+//		'\\' c      matches character c
+//		lo '-' hi   matches character c for lo <= c <= hi
+//
+// Match requires pattern to match all of name, not just a substring.
+// The only possible returned error is ErrBadPattern, when pattern
+// is malformed.
+//
+// On Windows, escaping is disabled. Instead, '\\' is treated as
+// path separator.
+func Match(pattern, name string) (matched bool, err error) {
+Pattern:
+	for len(pattern) > 0 {
+		var star bool
+		var chunk string
+		star, chunk, pattern = scanChunk(pattern)
+		if star && chunk == "" {
+			// Trailing * matches rest of string unless it has a /.
+			return !strings.Contains(name, string(Separator)), nil
+		}
+		// Look for match at current position.
+		t, ok, err := matchChunk(chunk, name)
+		// if we're the last chunk, make sure we've exhausted the name
+		// otherwise we'll give a false result even if we could still match
+		// using the star
+		if ok && (len(t) == 0 || len(pattern) > 0) {
+			name = t
+			continue
+		}
+		if err != nil {
+			return false, err
+		}
+		if star {
+			// Look for match skipping i+1 bytes.
+			// Cannot skip /.
+			for i := 0; i < len(name) && name[i] != Separator; i++ {
+				t, ok, err := matchChunk(chunk, name[i+1:])
+				if ok {
+					// if we're the last chunk, make sure we exhausted the name
+					if len(pattern) == 0 && len(t) > 0 {
+						continue
+					}
+					name = t
+					continue Pattern
+				}
+				if err != nil {
+					return false, err
+				}
+			}
+		}
+		return false, nil
+	}
+	return len(name) == 0, nil
+}
+
+// scanChunk gets the next segment of pattern, which is a non-star string
+// possibly preceded by a star.
+func scanChunk(pattern string) (star bool, chunk, rest string) {
+	for len(pattern) > 0 && pattern[0] == '*' {
+		pattern = pattern[1:]
+		star = true
+	}
+	inrange := false
+	var i int
+Scan:
+	for i = 0; i < len(pattern); i++ {
+		switch pattern[i] {
+		case '\\':
+			if runtime.GOOS != "windows" {
+				// error check handled in matchChunk: bad pattern.
+				if i+1 < len(pattern) {
+					i++
+				}
+			}
+		case '[':
+			inrange = true
+		case ']':
+			inrange = false
+		case '*':
+			if !inrange {
+				break Scan
+			}
+		}
+	}
+	return star, pattern[0:i], pattern[i:]
+}
+
+// matchChunk checks whether chunk matches the beginning of s.
+// If so, it returns the remainder of s (after the match).
+// Chunk is all single-character operators: literals, char classes, and ?.
+func matchChunk(chunk, s string) (rest string, ok bool, err error) {
+	// failed records whether the match has failed.
+	// After the match fails, the loop continues on processing chunk,
+	// checking that the pattern is well-formed but no longer reading s.
+	failed := false
+	for len(chunk) > 0 {
+		if !failed && len(s) == 0 {
+			failed = true
+		}
+		switch chunk[0] {
+		case '[':
+			// character class
+			var r rune
+			if !failed {
+				var n int
+				r, n = utf8.DecodeRuneInString(s)
+				s = s[n:]
+			}
+			chunk = chunk[1:]
+			// possibly negated
+			negated := false
+			if len(chunk) > 0 && chunk[0] == '^' {
+				negated = true
+				chunk = chunk[1:]
+			}
+			// parse all ranges
+			match := false
+			nrange := 0
+			for {
+				if len(chunk) > 0 && chunk[0] == ']' && nrange > 0 {
+					chunk = chunk[1:]
+					break
+				}
+				var lo, hi rune
+				if lo, chunk, err = getEsc(chunk); err != nil {
+					return "", false, err
+				}
+				hi = lo
+				if chunk[0] == '-' {
+					if hi, chunk, err = getEsc(chunk[1:]); err != nil {
+						return "", false, err
+					}
+				}
+				if lo <= r && r <= hi {
+					match = true
+				}
+				nrange++
+			}
+			if match == negated {
+				failed = true
+			}
+
+		case '?':
+			if !failed {
+				if s[0] == Separator {
+					failed = true
+				}
+				_, n := utf8.DecodeRuneInString(s)
+				s = s[n:]
+			}
+			chunk = chunk[1:]
+
+		case '\\':
+			if runtime.GOOS != "windows" {
+				chunk = chunk[1:]
+				if len(chunk) == 0 {
+					return "", false, ErrBadPattern
+				}
+			}
+			fallthrough
+
+		default:
+			if !failed {
+				if chunk[0] != s[0] {
+					failed = true
+				}
+				s = s[1:]
+			}
+			chunk = chunk[1:]
+		}
+	}
+	if failed {
+		return "", false, nil
+	}
+	return s, true, nil
+}
+
+// getEsc gets a possibly-escaped character from chunk, for a character class.
+func getEsc(chunk string) (r rune, nchunk string, err error) {
+	if len(chunk) == 0 || chunk[0] == '-' || chunk[0] == ']' {
+		err = ErrBadPattern
+		return
+	}
+	if chunk[0] == '\\' && runtime.GOOS != "windows" {
+		chunk = chunk[1:]
+		if len(chunk) == 0 {
+			err = ErrBadPattern
+			return
+		}
+	}
+	r, n := utf8.DecodeRuneInString(chunk)
+	if r == utf8.RuneError && n == 1 {
+		err = ErrBadPattern
+	}
+	nchunk = chunk[n:]
+	if len(nchunk) == 0 {
+		err = ErrBadPattern
+	}
+	return
+}
+
+// Glob returns the names of all files matching pattern or nil
+// if there is no matching file. The syntax of patterns is the same
+// as in Match. The pattern may describe hierarchical names such as
+// /usr/*/bin/ed (assuming the Separator is '/').
+//
+// Glob ignores file system errors such as I/O errors reading directories.
+// The only possible returned error is ErrBadPattern, when pattern
+// is malformed.
+func Glob(pattern string) (matches []string, err error) {
+	return globWithLimit(pattern, 0)
+}
+
+func globWithLimit(pattern string, depth int) (matches []string, err error) {
+	// This limit is used prevent stack exhaustion issues. See CVE-2022-30632.
+	const pathSeparatorsLimit = 10000
+	if depth == pathSeparatorsLimit {
+		return nil, ErrBadPattern
+	}
+
+	// Check pattern is well-formed.
+	if _, err := Match(pattern, ""); err != nil {
+		return nil, err
+	}
+	if !hasMeta(pattern) {
+		if _, err = os.Lstat(pattern); err != nil {
+			return nil, nil
+		}
+		return []string{pattern}, nil
+	}
+
+	dir, file := Split(pattern)
+	volumeLen := 0
+	if runtime.GOOS == "windows" {
+		volumeLen, dir = cleanGlobPathWindows(dir)
+	} else {
+		dir = cleanGlobPath(dir)
+	}
+
+	if !hasMeta(dir[volumeLen:]) {
+		return glob(dir, file, nil)
+	}
+
+	// Prevent infinite recursion. See issue 15879.
+	if dir == pattern {
+		return nil, ErrBadPattern
+	}
+
+	var m []string
+	m, err = globWithLimit(dir, depth+1)
+	if err != nil {
+		return
+	}
+	for _, d := range m {
+		matches, err = glob(d, file, matches)
+		if err != nil {
+			return
+		}
+	}
+	return
+}
+
+// cleanGlobPath prepares path for glob matching.
+func cleanGlobPath(path string) string {
+	switch path {
+	case "":
+		return "."
+	case string(Separator):
+		// do nothing to the path
+		return path
+	default:
+		return path[0 : len(path)-1] // chop off trailing separator
+	}
+}
+
+// cleanGlobPathWindows is windows version of cleanGlobPath.
+func cleanGlobPathWindows(path string) (prefixLen int, cleaned string) {
+	vollen := volumeNameLen(path)
+	switch {
+	case path == "":
+		return 0, "."
+	case vollen+1 == len(path) && os.IsPathSeparator(path[len(path)-1]): // /, \, C:\ and C:/
+		// do nothing to the path
+		return vollen + 1, path
+	case vollen == len(path) && len(path) == 2: // C:
+		return vollen, path + "." // convert C: into C:.
+	default:
+		if vollen >= len(path) {
+			vollen = len(path) - 1
+		}
+		return vollen, path[0 : len(path)-1] // chop off trailing separator
+	}
+}
+
+// glob searches for files matching pattern in the directory dir
+// and appends them to matches. If the directory cannot be
+// opened, it returns the existing matches. New matches are
+// added in lexicographical order.
+func glob(dir, pattern string, matches []string) (m []string, e error) {
+	m = matches
+	fi, err := os.Stat(dir)
+	if err != nil {
+		return // ignore I/O error
+	}
+	if !fi.IsDir() {
+		return // ignore I/O error
+	}
+	d, err := os.Open(dir)
+	if err != nil {
+		return // ignore I/O error
+	}
+	defer d.Close()
+
+	names, _ := d.Readdirnames(-1)
+	sort.Strings(names)
+
+	for _, n := range names {
+		matched, err := Match(pattern, n)
+		if err != nil {
+			return m, err
+		}
+		if matched {
+			m = append(m, Join(dir, n))
+		}
+	}
+	return
+}
+
+// hasMeta reports whether path contains any of the magic characters
+// recognized by Match.
+func hasMeta(path string) bool {
+	magicChars := `*?[`
+	if runtime.GOOS != "windows" {
+		magicChars = `*?[\`
+	}
+	return strings.ContainsAny(path, magicChars)
+}
diff --git a/contrib/go/_std_1.19/src/path/filepath/path.go b/contrib/go/_std_1.19/src/path/filepath/path.go
new file mode 100644
index 0000000000..de7a2c758b
--- /dev/null
+++ b/contrib/go/_std_1.19/src/path/filepath/path.go
@@ -0,0 +1,615 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package filepath implements utility routines for manipulating filename paths
+// in a way compatible with the target operating system-defined file paths.
+//
+// The filepath package uses either forward slashes or backslashes,
+// depending on the operating system. To process paths such as URLs
+// that always use forward slashes regardless of the operating
+// system, see the path package.
+package filepath
+
+import (
+	"errors"
+	"io/fs"
+	"os"
+	"sort"
+	"strings"
+)
+
+// A lazybuf is a lazily constructed path buffer.
+// It supports append, reading previously appended bytes,
+// and retrieving the final string. It does not allocate a buffer
+// to hold the output until that output diverges from s.
+type lazybuf struct {
+	path       string
+	buf        []byte
+	w          int
+	volAndPath string
+	volLen     int
+}
+
+func (b *lazybuf) index(i int) byte {
+	if b.buf != nil {
+		return b.buf[i]
+	}
+	return b.path[i]
+}
+
+func (b *lazybuf) append(c byte) {
+	if b.buf == nil {
+		if b.w < len(b.path) && b.path[b.w] == c {
+			b.w++
+			return
+		}
+		b.buf = make([]byte, len(b.path))
+		copy(b.buf, b.path[:b.w])
+	}
+	b.buf[b.w] = c
+	b.w++
+}
+
+func (b *lazybuf) string() string {
+	if b.buf == nil {
+		return b.volAndPath[:b.volLen+b.w]
+	}
+	return b.volAndPath[:b.volLen] + string(b.buf[:b.w])
+}
+
+const (
+	Separator     = os.PathSeparator
+	ListSeparator = os.PathListSeparator
+)
+
+// Clean returns the shortest path name equivalent to path
+// by purely lexical processing. It applies the following rules
+// iteratively until no further processing can be done:
+//
+//  1. Replace multiple Separator elements with a single one.
+//  2. Eliminate each . path name element (the current directory).
+//  3. Eliminate each inner .. path name element (the parent directory)
+//     along with the non-.. element that precedes it.
+//  4. Eliminate .. elements that begin a rooted path:
+//     that is, replace "/.." by "/" at the beginning of a path,
+//     assuming Separator is '/'.
+//
+// The returned path ends in a slash only if it represents a root directory,
+// such as "/" on Unix or `C:\` on Windows.
+//
+// Finally, any occurrences of slash are replaced by Separator.
+//
+// If the result of this process is an empty string, Clean
+// returns the string ".".
+//
+// See also Rob Pike, “Lexical File Names in Plan 9 or
+// Getting Dot-Dot Right,”
+// https://9p.io/sys/doc/lexnames.html
+func Clean(path string) string {
+	originalPath := path
+	volLen := volumeNameLen(path)
+	path = path[volLen:]
+	if path == "" {
+		if volLen > 1 && originalPath[1] != ':' {
+			// should be UNC
+			return FromSlash(originalPath)
+		}
+		return originalPath + "."
+	}
+	rooted := os.IsPathSeparator(path[0])
+
+	// Invariants:
+	//	reading from path; r is index of next byte to process.
+	//	writing to buf; w is index of next byte to write.
+	//	dotdot is index in buf where .. must stop, either because
+	//		it is the leading slash or it is a leading ../../.. prefix.
+	n := len(path)
+	out := lazybuf{path: path, volAndPath: originalPath, volLen: volLen}
+	r, dotdot := 0, 0
+	if rooted {
+		out.append(Separator)
+		r, dotdot = 1, 1
+	}
+
+	for r < n {
+		switch {
+		case os.IsPathSeparator(path[r]):
+			// empty path element
+			r++
+		case path[r] == '.' && r+1 == n:
+			// . element
+			r++
+		case path[r] == '.' && os.IsPathSeparator(path[r+1]):
+			// ./ element
+			r++
+
+			for r < len(path) && os.IsPathSeparator(path[r]) {
+				r++
+			}
+			if out.w == 0 && volumeNameLen(path[r:]) > 0 {
+				// When joining prefix "." and an absolute path on Windows,
+				// the prefix should not be removed.
+				out.append('.')
+			}
+		case path[r] == '.' && path[r+1] == '.' && (r+2 == n || os.IsPathSeparator(path[r+2])):
+			// .. element: remove to last separator
+			r += 2
+			switch {
+			case out.w > dotdot:
+				// can backtrack
+				out.w--
+				for out.w > dotdot && !os.IsPathSeparator(out.index(out.w)) {
+					out.w--
+				}
+			case !rooted:
+				// cannot backtrack, but not rooted, so append .. element.
+				if out.w > 0 {
+					out.append(Separator)
+				}
+				out.append('.')
+				out.append('.')
+				dotdot = out.w
+			}
+		default:
+			// real path element.
+			// add slash if needed
+			if rooted && out.w != 1 || !rooted && out.w != 0 {
+				out.append(Separator)
+			}
+			// copy element
+			for ; r < n && !os.IsPathSeparator(path[r]); r++ {
+				out.append(path[r])
+			}
+		}
+	}
+
+	// Turn empty string into "."
+	if out.w == 0 {
+		out.append('.')
+	}
+
+	return FromSlash(out.string())
+}
+
+// ToSlash returns the result of replacing each separator character
+// in path with a slash ('/') character. Multiple separators are
+// replaced by multiple slashes.
+func ToSlash(path string) string {
+	if Separator == '/' {
+		return path
+	}
+	return strings.ReplaceAll(path, string(Separator), "/")
+}
+
+// FromSlash returns the result of replacing each slash ('/') character
+// in path with a separator character. Multiple slashes are replaced
+// by multiple separators.
+func FromSlash(path string) string {
+	if Separator == '/' {
+		return path
+	}
+	return strings.ReplaceAll(path, "/", string(Separator))
+}
+
+// SplitList splits a list of paths joined by the OS-specific ListSeparator,
+// usually found in PATH or GOPATH environment variables.
+// Unlike strings.Split, SplitList returns an empty slice when passed an empty
+// string.
+func SplitList(path string) []string {
+	return splitList(path)
+}
+
+// Split splits path immediately following the final Separator,
+// separating it into a directory and file name component.
+// If there is no Separator in path, Split returns an empty dir
+// and file set to path.
+// The returned values have the property that path = dir+file.
+func Split(path string) (dir, file string) {
+	vol := VolumeName(path)
+	i := len(path) - 1
+	for i >= len(vol) && !os.IsPathSeparator(path[i]) {
+		i--
+	}
+	return path[:i+1], path[i+1:]
+}
+
+// Join joins any number of path elements into a single path,
+// separating them with an OS specific Separator. Empty elements
+// are ignored. The result is Cleaned. However, if the argument
+// list is empty or all its elements are empty, Join returns
+// an empty string.
+// On Windows, the result will only be a UNC path if the first
+// non-empty element is a UNC path.
+func Join(elem ...string) string {
+	return join(elem)
+}
+
+// Ext returns the file name extension used by path.
+// The extension is the suffix beginning at the final dot
+// in the final element of path; it is empty if there is
+// no dot.
+func Ext(path string) string {
+	for i := len(path) - 1; i >= 0 && !os.IsPathSeparator(path[i]); i-- {
+		if path[i] == '.' {
+			return path[i:]
+		}
+	}
+	return ""
+}
+
+// EvalSymlinks returns the path name after the evaluation of any symbolic
+// links.
+// If path is relative the result will be relative to the current directory,
+// unless one of the components is an absolute symbolic link.
+// EvalSymlinks calls Clean on the result.
+func EvalSymlinks(path string) (string, error) {
+	return evalSymlinks(path)
+}
+
+// Abs returns an absolute representation of path.
+// If the path is not absolute it will be joined with the current
+// working directory to turn it into an absolute path. The absolute
+// path name for a given file is not guaranteed to be unique.
+// Abs calls Clean on the result.
+func Abs(path string) (string, error) {
+	return abs(path)
+}
+
+func unixAbs(path string) (string, error) {
+	if IsAbs(path) {
+		return Clean(path), nil
+	}
+	wd, err := os.Getwd()
+	if err != nil {
+		return "", err
+	}
+	return Join(wd, path), nil
+}
+
+// Rel returns a relative path that is lexically equivalent to targpath when
+// joined to basepath with an intervening separator. That is,
+// Join(basepath, Rel(basepath, targpath)) is equivalent to targpath itself.
+// On success, the returned path will always be relative to basepath,
+// even if basepath and targpath share no elements.
+// An error is returned if targpath can't be made relative to basepath or if
+// knowing the current working directory would be necessary to compute it.
+// Rel calls Clean on the result.
+func Rel(basepath, targpath string) (string, error) {
+	baseVol := VolumeName(basepath)
+	targVol := VolumeName(targpath)
+	base := Clean(basepath)
+	targ := Clean(targpath)
+	if sameWord(targ, base) {
+		return ".", nil
+	}
+	base = base[len(baseVol):]
+	targ = targ[len(targVol):]
+	if base == "." {
+		base = ""
+	} else if base == "" && volumeNameLen(baseVol) > 2 /* isUNC */ {
+		// Treat any targetpath matching `\\host\share` basepath as absolute path.
+		base = string(Separator)
+	}
+
+	// Can't use IsAbs - `\a` and `a` are both relative in Windows.
+	baseSlashed := len(base) > 0 && base[0] == Separator
+	targSlashed := len(targ) > 0 && targ[0] == Separator
+	if baseSlashed != targSlashed || !sameWord(baseVol, targVol) {
+		return "", errors.New("Rel: can't make " + targpath + " relative to " + basepath)
+	}
+	// Position base[b0:bi] and targ[t0:ti] at the first differing elements.
+	bl := len(base)
+	tl := len(targ)
+	var b0, bi, t0, ti int
+	for {
+		for bi < bl && base[bi] != Separator {
+			bi++
+		}
+		for ti < tl && targ[ti] != Separator {
+			ti++
+		}
+		if !sameWord(targ[t0:ti], base[b0:bi]) {
+			break
+		}
+		if bi < bl {
+			bi++
+		}
+		if ti < tl {
+			ti++
+		}
+		b0 = bi
+		t0 = ti
+	}
+	if base[b0:bi] == ".." {
+		return "", errors.New("Rel: can't make " + targpath + " relative to " + basepath)
+	}
+	if b0 != bl {
+		// Base elements left. Must go up before going down.
+		seps := strings.Count(base[b0:bl], string(Separator))
+		size := 2 + seps*3
+		if tl != t0 {
+			size += 1 + tl - t0
+		}
+		buf := make([]byte, size)
+		n := copy(buf, "..")
+		for i := 0; i < seps; i++ {
+			buf[n] = Separator
+			copy(buf[n+1:], "..")
+			n += 3
+		}
+		if t0 != tl {
+			buf[n] = Separator
+			copy(buf[n+1:], targ[t0:])
+		}
+		return string(buf), nil
+	}
+	return targ[t0:], nil
+}
+
+// SkipDir is used as a return value from WalkFuncs to indicate that
+// the directory named in the call is to be skipped. It is not returned
+// as an error by any function.
+var SkipDir error = fs.SkipDir
+
+// WalkFunc is the type of the function called by Walk to visit each
+// file or directory.
+//
+// The path argument contains the argument to Walk as a prefix.
+// That is, if Walk is called with root argument "dir" and finds a file
+// named "a" in that directory, the walk function will be called with
+// argument "dir/a".
+//
+// The directory and file are joined with Join, which may clean the
+// directory name: if Walk is called with the root argument "x/../dir"
+// and finds a file named "a" in that directory, the walk function will
+// be called with argument "dir/a", not "x/../dir/a".
+//
+// The info argument is the fs.FileInfo for the named path.
+//
+// The error result returned by the function controls how Walk continues.
+// If the function returns the special value SkipDir, Walk skips the
+// current directory (path if info.IsDir() is true, otherwise path's
+// parent directory). Otherwise, if the function returns a non-nil error,
+// Walk stops entirely and returns that error.
+//
+// The err argument reports an error related to path, signaling that Walk
+// will not walk into that directory. The function can decide how to
+// handle that error; as described earlier, returning the error will
+// cause Walk to stop walking the entire tree.
+//
+// Walk calls the function with a non-nil err argument in two cases.
+//
+// First, if an os.Lstat on the root directory or any directory or file
+// in the tree fails, Walk calls the function with path set to that
+// directory or file's path, info set to nil, and err set to the error
+// from os.Lstat.
+//
+// Second, if a directory's Readdirnames method fails, Walk calls the
+// function with path set to the directory's path, info, set to an
+// fs.FileInfo describing the directory, and err set to the error from
+// Readdirnames.
+type WalkFunc func(path string, info fs.FileInfo, err error) error
+
+var lstat = os.Lstat // for testing
+
+// walkDir recursively descends path, calling walkDirFn.
+func walkDir(path string, d fs.DirEntry, walkDirFn fs.WalkDirFunc) error {
+	if err := walkDirFn(path, d, nil); err != nil || !d.IsDir() {
+		if err == SkipDir && d.IsDir() {
+			// Successfully skipped directory.
+			err = nil
+		}
+		return err
+	}
+
+	dirs, err := readDir(path)
+	if err != nil {
+		// Second call, to report ReadDir error.
+		err = walkDirFn(path, d, err)
+		if err != nil {
+			if err == SkipDir && d.IsDir() {
+				err = nil
+			}
+			return err
+		}
+	}
+
+	for _, d1 := range dirs {
+		path1 := Join(path, d1.Name())
+		if err := walkDir(path1, d1, walkDirFn); err != nil {
+			if err == SkipDir {
+				break
+			}
+			return err
+		}
+	}
+	return nil
+}
+
+// walk recursively descends path, calling walkFn.
+func walk(path string, info fs.FileInfo, walkFn WalkFunc) error {
+	if !info.IsDir() {
+		return walkFn(path, info, nil)
+	}
+
+	names, err := readDirNames(path)
+	err1 := walkFn(path, info, err)
+	// If err != nil, walk can't walk into this directory.
+	// err1 != nil means walkFn want walk to skip this directory or stop walking.
+	// Therefore, if one of err and err1 isn't nil, walk will return.
+	if err != nil || err1 != nil {
+		// The caller's behavior is controlled by the return value, which is decided
+		// by walkFn. walkFn may ignore err and return nil.
+		// If walkFn returns SkipDir, it will be handled by the caller.
+		// So walk should return whatever walkFn returns.
+		return err1
+	}
+
+	for _, name := range names {
+		filename := Join(path, name)
+		fileInfo, err := lstat(filename)
+		if err != nil {
+			if err := walkFn(filename, fileInfo, err); err != nil && err != SkipDir {
+				return err
+			}
+		} else {
+			err = walk(filename, fileInfo, walkFn)
+			if err != nil {
+				if !fileInfo.IsDir() || err != SkipDir {
+					return err
+				}
+			}
+		}
+	}
+	return nil
+}
+
+// WalkDir walks the file tree rooted at root, calling fn for each file or
+// directory in the tree, including root.
+//
+// All errors that arise visiting files and directories are filtered by fn:
+// see the fs.WalkDirFunc documentation for details.
+//
+// The files are walked in lexical order, which makes the output deterministic
+// but requires WalkDir to read an entire directory into memory before proceeding
+// to walk that directory.
+//
+// WalkDir does not follow symbolic links.
+func WalkDir(root string, fn fs.WalkDirFunc) error {
+	info, err := os.Lstat(root)
+	if err != nil {
+		err = fn(root, nil, err)
+	} else {
+		err = walkDir(root, &statDirEntry{info}, fn)
+	}
+	if err == SkipDir {
+		return nil
+	}
+	return err
+}
+
+type statDirEntry struct {
+	info fs.FileInfo
+}
+
+func (d *statDirEntry) Name() string               { return d.info.Name() }
+func (d *statDirEntry) IsDir() bool                { return d.info.IsDir() }
+func (d *statDirEntry) Type() fs.FileMode          { return d.info.Mode().Type() }
+func (d *statDirEntry) Info() (fs.FileInfo, error) { return d.info, nil }
+
+// Walk walks the file tree rooted at root, calling fn for each file or
+// directory in the tree, including root.
+//
+// All errors that arise visiting files and directories are filtered by fn:
+// see the WalkFunc documentation for details.
+//
+// The files are walked in lexical order, which makes the output deterministic
+// but requires Walk to read an entire directory into memory before proceeding
+// to walk that directory.
+//
+// Walk does not follow symbolic links.
+//
+// Walk is less efficient than WalkDir, introduced in Go 1.16,
+// which avoids calling os.Lstat on every visited file or directory.
+func Walk(root string, fn WalkFunc) error {
+	info, err := os.Lstat(root)
+	if err != nil {
+		err = fn(root, nil, err)
+	} else {
+		err = walk(root, info, fn)
+	}
+	if err == SkipDir {
+		return nil
+	}
+	return err
+}
+
+// readDir reads the directory named by dirname and returns
+// a sorted list of directory entries.
+func readDir(dirname string) ([]fs.DirEntry, error) {
+	f, err := os.Open(dirname)
+	if err != nil {
+		return nil, err
+	}
+	dirs, err := f.ReadDir(-1)
+	f.Close()
+	if err != nil {
+		return nil, err
+	}
+	sort.Slice(dirs, func(i, j int) bool { return dirs[i].Name() < dirs[j].Name() })
+	return dirs, nil
+}
+
+// readDirNames reads the directory named by dirname and returns
+// a sorted list of directory entry names.
+func readDirNames(dirname string) ([]string, error) {
+	f, err := os.Open(dirname)
+	if err != nil {
+		return nil, err
+	}
+	names, err := f.Readdirnames(-1)
+	f.Close()
+	if err != nil {
+		return nil, err
+	}
+	sort.Strings(names)
+	return names, nil
+}
+
+// Base returns the last element of path.
+// Trailing path separators are removed before extracting the last element.
+// If the path is empty, Base returns ".".
+// If the path consists entirely of separators, Base returns a single separator.
+func Base(path string) string {
+	if path == "" {
+		return "."
+	}
+	// Strip trailing slashes.
+	for len(path) > 0 && os.IsPathSeparator(path[len(path)-1]) {
+		path = path[0 : len(path)-1]
+	}
+	// Throw away volume name
+	path = path[len(VolumeName(path)):]
+	// Find the last element
+	i := len(path) - 1
+	for i >= 0 && !os.IsPathSeparator(path[i]) {
+		i--
+	}
+	if i >= 0 {
+		path = path[i+1:]
+	}
+	// If empty now, it had only slashes.
+	if path == "" {
+		return string(Separator)
+	}
+	return path
+}
+
+// Dir returns all but the last element of path, typically the path's directory.
+// After dropping the final element, Dir calls Clean on the path and trailing
+// slashes are removed.
+// If the path is empty, Dir returns ".".
+// If the path consists entirely of separators, Dir returns a single separator.
+// The returned path does not end in a separator unless it is the root directory.
+func Dir(path string) string {
+	vol := VolumeName(path)
+	i := len(path) - 1
+	for i >= len(vol) && !os.IsPathSeparator(path[i]) {
+		i--
+	}
+	dir := Clean(path[len(vol) : i+1])
+	if dir == "." && len(vol) > 2 {
+		// must be UNC
+		return vol
+	}
+	return vol + dir
+}
+
+// VolumeName returns leading volume name.
+// Given "C:\foo\bar" it returns "C:" on Windows.
+// Given "\\host\share\foo" it returns "\\host\share".
+// On other platforms it returns "".
+func VolumeName(path string) string {
+	return path[:volumeNameLen(path)]
+}
diff --git a/contrib/go/_std_1.19/src/path/filepath/path_unix.go b/contrib/go/_std_1.19/src/path/filepath/path_unix.go
new file mode 100644
index 0000000000..93fdfdd8a0
--- /dev/null
+++ b/contrib/go/_std_1.19/src/path/filepath/path_unix.go
@@ -0,0 +1,53 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm)
+
+package filepath
+
+import "strings"
+
+// IsAbs reports whether the path is absolute.
+func IsAbs(path string) bool {
+	return strings.HasPrefix(path, "/")
+}
+
+// volumeNameLen returns length of the leading volume name on Windows.
+// It returns 0 elsewhere.
+func volumeNameLen(path string) int {
+	return 0
+}
+
+// HasPrefix exists for historical compatibility and should not be used.
+//
+// Deprecated: HasPrefix does not respect path boundaries and
+// does not ignore case when required.
+func HasPrefix(p, prefix string) bool {
+	return strings.HasPrefix(p, prefix)
+}
+
+func splitList(path string) []string {
+	if path == "" {
+		return []string{}
+	}
+	return strings.Split(path, string(ListSeparator))
+}
+
+func abs(path string) (string, error) {
+	return unixAbs(path)
+}
+
+func join(elem []string) string {
+	// If there's a bug here, fix the logic in ./path_plan9.go too.
+	for i, e := range elem {
+		if e != "" {
+			return Clean(strings.Join(elem[i:], string(Separator)))
+		}
+	}
+	return ""
+}
+
+func sameWord(a, b string) bool {
+	return a == b
+}
diff --git a/contrib/go/_std_1.18/src/path/filepath/symlink.go b/contrib/go/_std_1.19/src/path/filepath/symlink.go
index 6fefd15977..6fefd15977 100644
--- a/contrib/go/_std_1.18/src/path/filepath/symlink.go
+++ b/contrib/go/_std_1.19/src/path/filepath/symlink.go
diff --git a/contrib/go/_std_1.19/src/path/filepath/symlink_unix.go b/contrib/go/_std_1.19/src/path/filepath/symlink_unix.go
new file mode 100644
index 0000000000..f8980d5ad3
--- /dev/null
+++ b/contrib/go/_std_1.19/src/path/filepath/symlink_unix.go
@@ -0,0 +1,7 @@
+//go:build !windows && !plan9
+
+package filepath
+
+func evalSymlinks(path string) (string, error) {
+	return walkSymlinks(path)
+}
diff --git a/contrib/go/_std_1.19/src/path/match.go b/contrib/go/_std_1.19/src/path/match.go
new file mode 100644
index 0000000000..673bbc7ff6
--- /dev/null
+++ b/contrib/go/_std_1.19/src/path/match.go
@@ -0,0 +1,230 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package path
+
+import (
+	"errors"
+	"internal/bytealg"
+	"unicode/utf8"
+)
+
+// ErrBadPattern indicates a pattern was malformed.
+var ErrBadPattern = errors.New("syntax error in pattern")
+
+// Match reports whether name matches the shell pattern.
+// The pattern syntax is:
+//
+//	pattern:
+//		{ term }
+//	term:
+//		'*'         matches any sequence of non-/ characters
+//		'?'         matches any single non-/ character
+//		'[' [ '^' ] { character-range } ']'
+//		            character class (must be non-empty)
+//		c           matches character c (c != '*', '?', '\\', '[')
+//		'\\' c      matches character c
+//
+//	character-range:
+//		c           matches character c (c != '\\', '-', ']')
+//		'\\' c      matches character c
+//		lo '-' hi   matches character c for lo <= c <= hi
+//
+// Match requires pattern to match all of name, not just a substring.
+// The only possible returned error is ErrBadPattern, when pattern
+// is malformed.
+func Match(pattern, name string) (matched bool, err error) {
+Pattern:
+	for len(pattern) > 0 {
+		var star bool
+		var chunk string
+		star, chunk, pattern = scanChunk(pattern)
+		if star && chunk == "" {
+			// Trailing * matches rest of string unless it has a /.
+			return bytealg.IndexByteString(name, '/') < 0, nil
+		}
+		// Look for match at current position.
+		t, ok, err := matchChunk(chunk, name)
+		// if we're the last chunk, make sure we've exhausted the name
+		// otherwise we'll give a false result even if we could still match
+		// using the star
+		if ok && (len(t) == 0 || len(pattern) > 0) {
+			name = t
+			continue
+		}
+		if err != nil {
+			return false, err
+		}
+		if star {
+			// Look for match skipping i+1 bytes.
+			// Cannot skip /.
+			for i := 0; i < len(name) && name[i] != '/'; i++ {
+				t, ok, err := matchChunk(chunk, name[i+1:])
+				if ok {
+					// if we're the last chunk, make sure we exhausted the name
+					if len(pattern) == 0 && len(t) > 0 {
+						continue
+					}
+					name = t
+					continue Pattern
+				}
+				if err != nil {
+					return false, err
+				}
+			}
+		}
+		// Before returning false with no error,
+		// check that the remainder of the pattern is syntactically valid.
+		for len(pattern) > 0 {
+			_, chunk, pattern = scanChunk(pattern)
+			if _, _, err := matchChunk(chunk, ""); err != nil {
+				return false, err
+			}
+		}
+		return false, nil
+	}
+	return len(name) == 0, nil
+}
+
+// scanChunk gets the next segment of pattern, which is a non-star string
+// possibly preceded by a star.
+func scanChunk(pattern string) (star bool, chunk, rest string) {
+	for len(pattern) > 0 && pattern[0] == '*' {
+		pattern = pattern[1:]
+		star = true
+	}
+	inrange := false
+	var i int
+Scan:
+	for i = 0; i < len(pattern); i++ {
+		switch pattern[i] {
+		case '\\':
+			// error check handled in matchChunk: bad pattern.
+			if i+1 < len(pattern) {
+				i++
+			}
+		case '[':
+			inrange = true
+		case ']':
+			inrange = false
+		case '*':
+			if !inrange {
+				break Scan
+			}
+		}
+	}
+	return star, pattern[0:i], pattern[i:]
+}
+
+// matchChunk checks whether chunk matches the beginning of s.
+// If so, it returns the remainder of s (after the match).
+// Chunk is all single-character operators: literals, char classes, and ?.
+func matchChunk(chunk, s string) (rest string, ok bool, err error) {
+	// failed records whether the match has failed.
+	// After the match fails, the loop continues on processing chunk,
+	// checking that the pattern is well-formed but no longer reading s.
+	failed := false
+	for len(chunk) > 0 {
+		if !failed && len(s) == 0 {
+			failed = true
+		}
+		switch chunk[0] {
+		case '[':
+			// character class
+			var r rune
+			if !failed {
+				var n int
+				r, n = utf8.DecodeRuneInString(s)
+				s = s[n:]
+			}
+			chunk = chunk[1:]
+			// possibly negated
+			negated := false
+			if len(chunk) > 0 && chunk[0] == '^' {
+				negated = true
+				chunk = chunk[1:]
+			}
+			// parse all ranges
+			match := false
+			nrange := 0
+			for {
+				if len(chunk) > 0 && chunk[0] == ']' && nrange > 0 {
+					chunk = chunk[1:]
+					break
+				}
+				var lo, hi rune
+				if lo, chunk, err = getEsc(chunk); err != nil {
+					return "", false, err
+				}
+				hi = lo
+				if chunk[0] == '-' {
+					if hi, chunk, err = getEsc(chunk[1:]); err != nil {
+						return "", false, err
+					}
+				}
+				if lo <= r && r <= hi {
+					match = true
+				}
+				nrange++
+			}
+			if match == negated {
+				failed = true
+			}
+
+		case '?':
+			if !failed {
+				if s[0] == '/' {
+					failed = true
+				}
+				_, n := utf8.DecodeRuneInString(s)
+				s = s[n:]
+			}
+			chunk = chunk[1:]
+
+		case '\\':
+			chunk = chunk[1:]
+			if len(chunk) == 0 {
+				return "", false, ErrBadPattern
+			}
+			fallthrough
+
+		default:
+			if !failed {
+				if chunk[0] != s[0] {
+					failed = true
+				}
+				s = s[1:]
+			}
+			chunk = chunk[1:]
+		}
+	}
+	if failed {
+		return "", false, nil
+	}
+	return s, true, nil
+}
+
+// getEsc gets a possibly-escaped character from chunk, for a character class.
+func getEsc(chunk string) (r rune, nchunk string, err error) {
+	if len(chunk) == 0 || chunk[0] == '-' || chunk[0] == ']' {
+		err = ErrBadPattern
+		return
+	}
+	if chunk[0] == '\\' {
+		chunk = chunk[1:]
+		if len(chunk) == 0 {
+			err = ErrBadPattern
+			return
+		}
+	}
+	r, n := utf8.DecodeRuneInString(chunk)
+	if r == utf8.RuneError && n == 1 {
+		err = ErrBadPattern
+	}
+	nchunk = chunk[n:]
+	if len(nchunk) == 0 {
+		err = ErrBadPattern
+	}
+	return
+}
diff --git a/contrib/go/_std_1.19/src/path/path.go b/contrib/go/_std_1.19/src/path/path.go
new file mode 100644
index 0000000000..547b9debce
--- /dev/null
+++ b/contrib/go/_std_1.19/src/path/path.go
@@ -0,0 +1,233 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package path implements utility routines for manipulating slash-separated
+// paths.
+//
+// The path package should only be used for paths separated by forward
+// slashes, such as the paths in URLs. This package does not deal with
+// Windows paths with drive letters or backslashes; to manipulate
+// operating system paths, use the path/filepath package.
+package path
+
+// A lazybuf is a lazily constructed path buffer.
+// It supports append, reading previously appended bytes,
+// and retrieving the final string. It does not allocate a buffer
+// to hold the output until that output diverges from s.
+type lazybuf struct {
+	s   string
+	buf []byte
+	w   int
+}
+
+func (b *lazybuf) index(i int) byte {
+	if b.buf != nil {
+		return b.buf[i]
+	}
+	return b.s[i]
+}
+
+func (b *lazybuf) append(c byte) {
+	if b.buf == nil {
+		if b.w < len(b.s) && b.s[b.w] == c {
+			b.w++
+			return
+		}
+		b.buf = make([]byte, len(b.s))
+		copy(b.buf, b.s[:b.w])
+	}
+	b.buf[b.w] = c
+	b.w++
+}
+
+func (b *lazybuf) string() string {
+	if b.buf == nil {
+		return b.s[:b.w]
+	}
+	return string(b.buf[:b.w])
+}
+
+// Clean returns the shortest path name equivalent to path
+// by purely lexical processing. It applies the following rules
+// iteratively until no further processing can be done:
+//
+//  1. Replace multiple slashes with a single slash.
+//  2. Eliminate each . path name element (the current directory).
+//  3. Eliminate each inner .. path name element (the parent directory)
+//     along with the non-.. element that precedes it.
+//  4. Eliminate .. elements that begin a rooted path:
+//     that is, replace "/.." by "/" at the beginning of a path.
+//
+// The returned path ends in a slash only if it is the root "/".
+//
+// If the result of this process is an empty string, Clean
+// returns the string ".".
+//
+// See also Rob Pike, “Lexical File Names in Plan 9 or
+// Getting Dot-Dot Right,”
+// https://9p.io/sys/doc/lexnames.html
+func Clean(path string) string {
+	if path == "" {
+		return "."
+	}
+
+	rooted := path[0] == '/'
+	n := len(path)
+
+	// Invariants:
+	//	reading from path; r is index of next byte to process.
+	//	writing to buf; w is index of next byte to write.
+	//	dotdot is index in buf where .. must stop, either because
+	//		it is the leading slash or it is a leading ../../.. prefix.
+	out := lazybuf{s: path}
+	r, dotdot := 0, 0
+	if rooted {
+		out.append('/')
+		r, dotdot = 1, 1
+	}
+
+	for r < n {
+		switch {
+		case path[r] == '/':
+			// empty path element
+			r++
+		case path[r] == '.' && (r+1 == n || path[r+1] == '/'):
+			// . element
+			r++
+		case path[r] == '.' && path[r+1] == '.' && (r+2 == n || path[r+2] == '/'):
+			// .. element: remove to last /
+			r += 2
+			switch {
+			case out.w > dotdot:
+				// can backtrack
+				out.w--
+				for out.w > dotdot && out.index(out.w) != '/' {
+					out.w--
+				}
+			case !rooted:
+				// cannot backtrack, but not rooted, so append .. element.
+				if out.w > 0 {
+					out.append('/')
+				}
+				out.append('.')
+				out.append('.')
+				dotdot = out.w
+			}
+		default:
+			// real path element.
+			// add slash if needed
+			if rooted && out.w != 1 || !rooted && out.w != 0 {
+				out.append('/')
+			}
+			// copy element
+			for ; r < n && path[r] != '/'; r++ {
+				out.append(path[r])
+			}
+		}
+	}
+
+	// Turn empty string into "."
+	if out.w == 0 {
+		return "."
+	}
+
+	return out.string()
+}
+
+// lastSlash(s) is strings.LastIndex(s, "/") but we can't import strings.
+func lastSlash(s string) int {
+	i := len(s) - 1
+	for i >= 0 && s[i] != '/' {
+		i--
+	}
+	return i
+}
+
+// Split splits path immediately following the final slash,
+// separating it into a directory and file name component.
+// If there is no slash in path, Split returns an empty dir and
+// file set to path.
+// The returned values have the property that path = dir+file.
+func Split(path string) (dir, file string) {
+	i := lastSlash(path)
+	return path[:i+1], path[i+1:]
+}
+
+// Join joins any number of path elements into a single path,
+// separating them with slashes. Empty elements are ignored.
+// The result is Cleaned. However, if the argument list is
+// empty or all its elements are empty, Join returns
+// an empty string.
+func Join(elem ...string) string {
+	size := 0
+	for _, e := range elem {
+		size += len(e)
+	}
+	if size == 0 {
+		return ""
+	}
+	buf := make([]byte, 0, size+len(elem)-1)
+	for _, e := range elem {
+		if len(buf) > 0 || e != "" {
+			if len(buf) > 0 {
+				buf = append(buf, '/')
+			}
+			buf = append(buf, e...)
+		}
+	}
+	return Clean(string(buf))
+}
+
+// Ext returns the file name extension used by path.
+// The extension is the suffix beginning at the final dot
+// in the final slash-separated element of path;
+// it is empty if there is no dot.
+func Ext(path string) string {
+	for i := len(path) - 1; i >= 0 && path[i] != '/'; i-- {
+		if path[i] == '.' {
+			return path[i:]
+		}
+	}
+	return ""
+}
+
+// Base returns the last element of path.
+// Trailing slashes are removed before extracting the last element.
+// If the path is empty, Base returns ".".
+// If the path consists entirely of slashes, Base returns "/".
+func Base(path string) string {
+	if path == "" {
+		return "."
+	}
+	// Strip trailing slashes.
+	for len(path) > 0 && path[len(path)-1] == '/' {
+		path = path[0 : len(path)-1]
+	}
+	// Find the last element
+	if i := lastSlash(path); i >= 0 {
+		path = path[i+1:]
+	}
+	// If empty now, it had only slashes.
+	if path == "" {
+		return "/"
+	}
+	return path
+}
+
+// IsAbs reports whether the path is absolute.
+func IsAbs(path string) bool {
+	return len(path) > 0 && path[0] == '/'
+}
+
+// Dir returns all but the last element of path, typically the path's directory.
+// After dropping the final element using Split, the path is Cleaned and trailing
+// slashes are removed.
+// If the path is empty, Dir returns ".".
+// If the path consists entirely of slashes followed by non-slash bytes, Dir
+// returns a single slash. In any other case, the returned path does not end in a
+// slash.
+func Dir(path string) string {
+	dir, _ := Split(path)
+	return Clean(dir)
+}
diff --git a/contrib/go/_std_1.19/src/reflect/abi.go b/contrib/go/_std_1.19/src/reflect/abi.go
new file mode 100644
index 0000000000..32cb314188
--- /dev/null
+++ b/contrib/go/_std_1.19/src/reflect/abi.go
@@ -0,0 +1,510 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package reflect
+
+import (
+	"internal/abi"
+	"internal/goarch"
+	"unsafe"
+)
+
+// These variables are used by the register assignment
+// algorithm in this file.
+//
+// They should be modified with care (no other reflect code
+// may be executing) and are generally only modified
+// when testing this package.
+//
+// They should never be set higher than their internal/abi
+// constant counterparts, because the system relies on a
+// structure that is at least large enough to hold the
+// registers the system supports.
+//
+// Currently they're set to zero because using the actual
+// constants will break every part of the toolchain that
+// uses reflect to call functions (e.g. go test, or anything
+// that uses text/template). The values that are currently
+// commented out there should be the actual values once
+// we're ready to use the register ABI everywhere.
+var (
+	intArgRegs   = abi.IntArgRegs
+	floatArgRegs = abi.FloatArgRegs
+	floatRegSize = uintptr(abi.EffectiveFloatRegSize)
+)
+
+// abiStep represents an ABI "instruction." Each instruction
+// describes one part of how to translate between a Go value
+// in memory and a call frame.
+type abiStep struct {
+	kind abiStepKind
+
+	// offset and size together describe a part of a Go value
+	// in memory.
+	offset uintptr
+	size   uintptr // size in bytes of the part
+
+	// These fields describe the ABI side of the translation.
+	stkOff uintptr // stack offset, used if kind == abiStepStack
+	ireg   int     // integer register index, used if kind == abiStepIntReg or kind == abiStepPointer
+	freg   int     // FP register index, used if kind == abiStepFloatReg
+}
+
+// abiStepKind is the "op-code" for an abiStep instruction.
+type abiStepKind int
+
+const (
+	abiStepBad      abiStepKind = iota
+	abiStepStack                // copy to/from stack
+	abiStepIntReg               // copy to/from integer register
+	abiStepPointer              // copy pointer to/from integer register
+	abiStepFloatReg             // copy to/from FP register
+)
+
+// abiSeq represents a sequence of ABI instructions for copying
+// from a series of reflect.Values to a call frame (for call arguments)
+// or vice-versa (for call results).
+//
+// An abiSeq should be populated by calling its addArg method.
+type abiSeq struct {
+	// steps is the set of instructions.
+	//
+	// The instructions are grouped together by whole arguments,
+	// with the starting index for the instructions
+	// of the i'th Go value available in valueStart.
+	//
+	// For instance, if this abiSeq represents 3 arguments
+	// passed to a function, then the 2nd argument's steps
+	// begin at steps[valueStart[1]].
+	//
+	// Because reflect accepts Go arguments in distinct
+	// Values and each Value is stored separately, each abiStep
+	// that begins a new argument will have its offset
+	// field == 0.
+	steps      []abiStep
+	valueStart []int
+
+	stackBytes   uintptr // stack space used
+	iregs, fregs int     // registers used
+}
+
+func (a *abiSeq) dump() {
+	for i, p := range a.steps {
+		println("part", i, p.kind, p.offset, p.size, p.stkOff, p.ireg, p.freg)
+	}
+	print("values ")
+	for _, i := range a.valueStart {
+		print(i, " ")
+	}
+	println()
+	println("stack", a.stackBytes)
+	println("iregs", a.iregs)
+	println("fregs", a.fregs)
+}
+
+// stepsForValue returns the ABI instructions for translating
+// the i'th Go argument or return value represented by this
+// abiSeq to the Go ABI.
+func (a *abiSeq) stepsForValue(i int) []abiStep {
+	s := a.valueStart[i]
+	var e int
+	if i == len(a.valueStart)-1 {
+		e = len(a.steps)
+	} else {
+		e = a.valueStart[i+1]
+	}
+	return a.steps[s:e]
+}
+
+// addArg extends the abiSeq with a new Go value of type t.
+//
+// If the value was stack-assigned, returns the single
+// abiStep describing that translation, and nil otherwise.
+func (a *abiSeq) addArg(t *rtype) *abiStep {
+	// We'll always be adding a new value, so do that first.
+	pStart := len(a.steps)
+	a.valueStart = append(a.valueStart, pStart)
+	if t.size == 0 {
+		// If the size of the argument type is zero, then
+		// in order to degrade gracefully into ABI0, we need
+		// to stack-assign this type. The reason is that
+		// although zero-sized types take up no space on the
+		// stack, they do cause the next argument to be aligned.
+		// So just do that here, but don't bother actually
+		// generating a new ABI step for it (there's nothing to
+		// actually copy).
+		//
+		// We cannot handle this in the recursive case of
+		// regAssign because zero-sized *fields* of a
+		// non-zero-sized struct do not cause it to be
+		// stack-assigned. So we need a special case here
+		// at the top.
+		a.stackBytes = align(a.stackBytes, uintptr(t.align))
+		return nil
+	}
+	// Hold a copy of "a" so that we can roll back if
+	// register assignment fails.
+	aOld := *a
+	if !a.regAssign(t, 0) {
+		// Register assignment failed. Roll back any changes
+		// and stack-assign.
+		*a = aOld
+		a.stackAssign(t.size, uintptr(t.align))
+		return &a.steps[len(a.steps)-1]
+	}
+	return nil
+}
+
+// addRcvr extends the abiSeq with a new method call
+// receiver according to the interface calling convention.
+//
+// If the receiver was stack-assigned, returns the single
+// abiStep describing that translation, and nil otherwise.
+// Returns true if the receiver is a pointer.
+func (a *abiSeq) addRcvr(rcvr *rtype) (*abiStep, bool) {
+	// The receiver is always one word.
+	a.valueStart = append(a.valueStart, len(a.steps))
+	var ok, ptr bool
+	if ifaceIndir(rcvr) || rcvr.pointers() {
+		ok = a.assignIntN(0, goarch.PtrSize, 1, 0b1)
+		ptr = true
+	} else {
+		// TODO(mknyszek): Is this case even possible?
+		// The interface data work never contains a non-pointer
+		// value. This case was copied over from older code
+		// in the reflect package which only conditionally added
+		// a pointer bit to the reflect.(Value).Call stack frame's
+		// GC bitmap.
+		ok = a.assignIntN(0, goarch.PtrSize, 1, 0b0)
+		ptr = false
+	}
+	if !ok {
+		a.stackAssign(goarch.PtrSize, goarch.PtrSize)
+		return &a.steps[len(a.steps)-1], ptr
+	}
+	return nil, ptr
+}
+
+// regAssign attempts to reserve argument registers for a value of
+// type t, stored at some offset.
+//
+// It returns whether or not the assignment succeeded, but
+// leaves any changes it made to a.steps behind, so the caller
+// must undo that work by adjusting a.steps if it fails.
+//
+// This method along with the assign* methods represent the
+// complete register-assignment algorithm for the Go ABI.
+func (a *abiSeq) regAssign(t *rtype, offset uintptr) bool {
+	switch t.Kind() {
+	case UnsafePointer, Pointer, Chan, Map, Func:
+		return a.assignIntN(offset, t.size, 1, 0b1)
+	case Bool, Int, Uint, Int8, Uint8, Int16, Uint16, Int32, Uint32, Uintptr:
+		return a.assignIntN(offset, t.size, 1, 0b0)
+	case Int64, Uint64:
+		switch goarch.PtrSize {
+		case 4:
+			return a.assignIntN(offset, 4, 2, 0b0)
+		case 8:
+			return a.assignIntN(offset, 8, 1, 0b0)
+		}
+	case Float32, Float64:
+		return a.assignFloatN(offset, t.size, 1)
+	case Complex64:
+		return a.assignFloatN(offset, 4, 2)
+	case Complex128:
+		return a.assignFloatN(offset, 8, 2)
+	case String:
+		return a.assignIntN(offset, goarch.PtrSize, 2, 0b01)
+	case Interface:
+		return a.assignIntN(offset, goarch.PtrSize, 2, 0b10)
+	case Slice:
+		return a.assignIntN(offset, goarch.PtrSize, 3, 0b001)
+	case Array:
+		tt := (*arrayType)(unsafe.Pointer(t))
+		switch tt.len {
+		case 0:
+			// There's nothing to assign, so don't modify
+			// a.steps but succeed so the caller doesn't
+			// try to stack-assign this value.
+			return true
+		case 1:
+			return a.regAssign(tt.elem, offset)
+		default:
+			return false
+		}
+	case Struct:
+		st := (*structType)(unsafe.Pointer(t))
+		for i := range st.fields {
+			f := &st.fields[i]
+			if !a.regAssign(f.typ, offset+f.offset) {
+				return false
+			}
+		}
+		return true
+	default:
+		print("t.Kind == ", t.Kind(), "\n")
+		panic("unknown type kind")
+	}
+	panic("unhandled register assignment path")
+}
+
+// assignIntN assigns n values to registers, each "size" bytes large,
+// from the data at [offset, offset+n*size) in memory. Each value at
+// [offset+i*size, offset+(i+1)*size) for i < n is assigned to the
+// next n integer registers.
+//
+// Bit i in ptrMap indicates whether the i'th value is a pointer.
+// n must be <= 8.
+//
+// Returns whether assignment succeeded.
+func (a *abiSeq) assignIntN(offset, size uintptr, n int, ptrMap uint8) bool {
+	if n > 8 || n < 0 {
+		panic("invalid n")
+	}
+	if ptrMap != 0 && size != goarch.PtrSize {
+		panic("non-empty pointer map passed for non-pointer-size values")
+	}
+	if a.iregs+n > intArgRegs {
+		return false
+	}
+	for i := 0; i < n; i++ {
+		kind := abiStepIntReg
+		if ptrMap&(uint8(1)<<i) != 0 {
+			kind = abiStepPointer
+		}
+		a.steps = append(a.steps, abiStep{
+			kind:   kind,
+			offset: offset + uintptr(i)*size,
+			size:   size,
+			ireg:   a.iregs,
+		})
+		a.iregs++
+	}
+	return true
+}
+
+// assignFloatN assigns n values to registers, each "size" bytes large,
+// from the data at [offset, offset+n*size) in memory. Each value at
+// [offset+i*size, offset+(i+1)*size) for i < n is assigned to the
+// next n floating-point registers.
+//
+// Returns whether assignment succeeded.
+func (a *abiSeq) assignFloatN(offset, size uintptr, n int) bool {
+	if n < 0 {
+		panic("invalid n")
+	}
+	if a.fregs+n > floatArgRegs || floatRegSize < size {
+		return false
+	}
+	for i := 0; i < n; i++ {
+		a.steps = append(a.steps, abiStep{
+			kind:   abiStepFloatReg,
+			offset: offset + uintptr(i)*size,
+			size:   size,
+			freg:   a.fregs,
+		})
+		a.fregs++
+	}
+	return true
+}
+
+// stackAssign reserves space for one value that is "size" bytes
+// large with alignment "alignment" to the stack.
+//
+// Should not be called directly; use addArg instead.
+func (a *abiSeq) stackAssign(size, alignment uintptr) {
+	a.stackBytes = align(a.stackBytes, alignment)
+	a.steps = append(a.steps, abiStep{
+		kind:   abiStepStack,
+		offset: 0, // Only used for whole arguments, so the memory offset is 0.
+		size:   size,
+		stkOff: a.stackBytes,
+	})
+	a.stackBytes += size
+}
+
+// abiDesc describes the ABI for a function or method.
+type abiDesc struct {
+	// call and ret represent the translation steps for
+	// the call and return paths of a Go function.
+	call, ret abiSeq
+
+	// These fields describe the stack space allocated
+	// for the call. stackCallArgsSize is the amount of space
+	// reserved for arguments but not return values. retOffset
+	// is the offset at which return values begin, and
+	// spill is the size in bytes of additional space reserved
+	// to spill argument registers into in case of preemption in
+	// reflectcall's stack frame.
+	stackCallArgsSize, retOffset, spill uintptr
+
+	// stackPtrs is a bitmap that indicates whether
+	// each word in the ABI stack space (stack-assigned
+	// args + return values) is a pointer. Used
+	// as the heap pointer bitmap for stack space
+	// passed to reflectcall.
+	stackPtrs *bitVector
+
+	// inRegPtrs is a bitmap whose i'th bit indicates
+	// whether the i'th integer argument register contains
+	// a pointer. Used by makeFuncStub and methodValueCall
+	// to make result pointers visible to the GC.
+	//
+	// outRegPtrs is the same, but for result values.
+	// Used by reflectcall to make result pointers visible
+	// to the GC.
+	inRegPtrs, outRegPtrs abi.IntArgRegBitmap
+}
+
+func (a *abiDesc) dump() {
+	println("ABI")
+	println("call")
+	a.call.dump()
+	println("ret")
+	a.ret.dump()
+	println("stackCallArgsSize", a.stackCallArgsSize)
+	println("retOffset", a.retOffset)
+	println("spill", a.spill)
+	print("inRegPtrs:")
+	dumpPtrBitMap(a.inRegPtrs)
+	println()
+	print("outRegPtrs:")
+	dumpPtrBitMap(a.outRegPtrs)
+	println()
+}
+
+func dumpPtrBitMap(b abi.IntArgRegBitmap) {
+	for i := 0; i < intArgRegs; i++ {
+		x := 0
+		if b.Get(i) {
+			x = 1
+		}
+		print(" ", x)
+	}
+}
+
+func newAbiDesc(t *funcType, rcvr *rtype) abiDesc {
+	// We need to add space for this argument to
+	// the frame so that it can spill args into it.
+	//
+	// The size of this space is just the sum of the sizes
+	// of each register-allocated type.
+	//
+	// TODO(mknyszek): Remove this when we no longer have
+	// caller reserved spill space.
+	spill := uintptr(0)
+
+	// Compute gc program & stack bitmap for stack arguments
+	stackPtrs := new(bitVector)
+
+	// Compute the stack frame pointer bitmap and register
+	// pointer bitmap for arguments.
+	inRegPtrs := abi.IntArgRegBitmap{}
+
+	// Compute abiSeq for input parameters.
+	var in abiSeq
+	if rcvr != nil {
+		stkStep, isPtr := in.addRcvr(rcvr)
+		if stkStep != nil {
+			if isPtr {
+				stackPtrs.append(1)
+			} else {
+				stackPtrs.append(0)
+			}
+		} else {
+			spill += goarch.PtrSize
+		}
+	}
+	for i, arg := range t.in() {
+		stkStep := in.addArg(arg)
+		if stkStep != nil {
+			addTypeBits(stackPtrs, stkStep.stkOff, arg)
+		} else {
+			spill = align(spill, uintptr(arg.align))
+			spill += arg.size
+			for _, st := range in.stepsForValue(i) {
+				if st.kind == abiStepPointer {
+					inRegPtrs.Set(st.ireg)
+				}
+			}
+		}
+	}
+	spill = align(spill, goarch.PtrSize)
+
+	// From the input parameters alone, we now know
+	// the stackCallArgsSize and retOffset.
+	stackCallArgsSize := in.stackBytes
+	retOffset := align(in.stackBytes, goarch.PtrSize)
+
+	// Compute the stack frame pointer bitmap and register
+	// pointer bitmap for return values.
+	outRegPtrs := abi.IntArgRegBitmap{}
+
+	// Compute abiSeq for output parameters.
+	var out abiSeq
+	// Stack-assigned return values do not share
+	// space with arguments like they do with registers,
+	// so we need to inject a stack offset here.
+	// Fake it by artificially extending stackBytes by
+	// the return offset.
+	out.stackBytes = retOffset
+	for i, res := range t.out() {
+		stkStep := out.addArg(res)
+		if stkStep != nil {
+			addTypeBits(stackPtrs, stkStep.stkOff, res)
+		} else {
+			for _, st := range out.stepsForValue(i) {
+				if st.kind == abiStepPointer {
+					outRegPtrs.Set(st.ireg)
+				}
+			}
+		}
+	}
+	// Undo the faking from earlier so that stackBytes
+	// is accurate.
+	out.stackBytes -= retOffset
+	return abiDesc{in, out, stackCallArgsSize, retOffset, spill, stackPtrs, inRegPtrs, outRegPtrs}
+}
+
+// intFromReg loads an argSize sized integer from reg and places it at to.
+//
+// argSize must be non-zero, fit in a register, and a power-of-two.
+func intFromReg(r *abi.RegArgs, reg int, argSize uintptr, to unsafe.Pointer) {
+	memmove(to, r.IntRegArgAddr(reg, argSize), argSize)
+}
+
+// intToReg loads an argSize sized integer and stores it into reg.
+//
+// argSize must be non-zero, fit in a register, and a power-of-two.
+func intToReg(r *abi.RegArgs, reg int, argSize uintptr, from unsafe.Pointer) {
+	memmove(r.IntRegArgAddr(reg, argSize), from, argSize)
+}
+
+// floatFromReg loads a float value from its register representation in r.
+//
+// argSize must be 4 or 8.
+func floatFromReg(r *abi.RegArgs, reg int, argSize uintptr, to unsafe.Pointer) {
+	switch argSize {
+	case 4:
+		*(*float32)(to) = archFloat32FromReg(r.Floats[reg])
+	case 8:
+		*(*float64)(to) = *(*float64)(unsafe.Pointer(&r.Floats[reg]))
+	default:
+		panic("bad argSize")
+	}
+}
+
+// floatToReg stores a float value in its register representation in r.
+//
+// argSize must be either 4 or 8.
+func floatToReg(r *abi.RegArgs, reg int, argSize uintptr, from unsafe.Pointer) {
+	switch argSize {
+	case 4:
+		r.Floats[reg] = archFloat32ToReg(*(*float32)(from))
+	case 8:
+		r.Floats[reg] = *(*uint64)(from)
+	default:
+		panic("bad argSize")
+	}
+}
diff --git a/contrib/go/_std_1.18/src/reflect/asm_amd64.s b/contrib/go/_std_1.19/src/reflect/asm_amd64.s
index d21d498063..d21d498063 100644
--- a/contrib/go/_std_1.18/src/reflect/asm_amd64.s
+++ b/contrib/go/_std_1.19/src/reflect/asm_amd64.s
diff --git a/contrib/go/_std_1.19/src/reflect/deepequal.go b/contrib/go/_std_1.19/src/reflect/deepequal.go
new file mode 100644
index 0000000000..50b436e5f6
--- /dev/null
+++ b/contrib/go/_std_1.19/src/reflect/deepequal.go
@@ -0,0 +1,238 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Deep equality test via reflection
+
+package reflect
+
+import (
+	"internal/bytealg"
+	"unsafe"
+)
+
+// During deepValueEqual, must keep track of checks that are
+// in progress. The comparison algorithm assumes that all
+// checks in progress are true when it reencounters them.
+// Visited comparisons are stored in a map indexed by visit.
+type visit struct {
+	a1  unsafe.Pointer
+	a2  unsafe.Pointer
+	typ Type
+}
+
+// Tests for deep equality using reflected types. The map argument tracks
+// comparisons that have already been seen, which allows short circuiting on
+// recursive types.
+func deepValueEqual(v1, v2 Value, visited map[visit]bool) bool {
+	if !v1.IsValid() || !v2.IsValid() {
+		return v1.IsValid() == v2.IsValid()
+	}
+	if v1.Type() != v2.Type() {
+		return false
+	}
+
+	// We want to avoid putting more in the visited map than we need to.
+	// For any possible reference cycle that might be encountered,
+	// hard(v1, v2) needs to return true for at least one of the types in the cycle,
+	// and it's safe and valid to get Value's internal pointer.
+	hard := func(v1, v2 Value) bool {
+		switch v1.Kind() {
+		case Pointer:
+			if v1.typ.ptrdata == 0 {
+				// go:notinheap pointers can't be cyclic.
+				// At least, all of our current uses of go:notinheap have
+				// that property. The runtime ones aren't cyclic (and we don't use
+				// DeepEqual on them anyway), and the cgo-generated ones are
+				// all empty structs.
+				return false
+			}
+			fallthrough
+		case Map, Slice, Interface:
+			// Nil pointers cannot be cyclic. Avoid putting them in the visited map.
+			return !v1.IsNil() && !v2.IsNil()
+		}
+		return false
+	}
+
+	if hard(v1, v2) {
+		// For a Pointer or Map value, we need to check flagIndir,
+		// which we do by calling the pointer method.
+		// For Slice or Interface, flagIndir is always set,
+		// and using v.ptr suffices.
+		ptrval := func(v Value) unsafe.Pointer {
+			switch v.Kind() {
+			case Pointer, Map:
+				return v.pointer()
+			default:
+				return v.ptr
+			}
+		}
+		addr1 := ptrval(v1)
+		addr2 := ptrval(v2)
+		if uintptr(addr1) > uintptr(addr2) {
+			// Canonicalize order to reduce number of entries in visited.
+			// Assumes non-moving garbage collector.
+			addr1, addr2 = addr2, addr1
+		}
+
+		// Short circuit if references are already seen.
+		typ := v1.Type()
+		v := visit{addr1, addr2, typ}
+		if visited[v] {
+			return true
+		}
+
+		// Remember for later.
+		visited[v] = true
+	}
+
+	switch v1.Kind() {
+	case Array:
+		for i := 0; i < v1.Len(); i++ {
+			if !deepValueEqual(v1.Index(i), v2.Index(i), visited) {
+				return false
+			}
+		}
+		return true
+	case Slice:
+		if v1.IsNil() != v2.IsNil() {
+			return false
+		}
+		if v1.Len() != v2.Len() {
+			return false
+		}
+		if v1.UnsafePointer() == v2.UnsafePointer() {
+			return true
+		}
+		// Special case for []byte, which is common.
+		if v1.Type().Elem().Kind() == Uint8 {
+			return bytealg.Equal(v1.Bytes(), v2.Bytes())
+		}
+		for i := 0; i < v1.Len(); i++ {
+			if !deepValueEqual(v1.Index(i), v2.Index(i), visited) {
+				return false
+			}
+		}
+		return true
+	case Interface:
+		if v1.IsNil() || v2.IsNil() {
+			return v1.IsNil() == v2.IsNil()
+		}
+		return deepValueEqual(v1.Elem(), v2.Elem(), visited)
+	case Pointer:
+		if v1.UnsafePointer() == v2.UnsafePointer() {
+			return true
+		}
+		return deepValueEqual(v1.Elem(), v2.Elem(), visited)
+	case Struct:
+		for i, n := 0, v1.NumField(); i < n; i++ {
+			if !deepValueEqual(v1.Field(i), v2.Field(i), visited) {
+				return false
+			}
+		}
+		return true
+	case Map:
+		if v1.IsNil() != v2.IsNil() {
+			return false
+		}
+		if v1.Len() != v2.Len() {
+			return false
+		}
+		if v1.UnsafePointer() == v2.UnsafePointer() {
+			return true
+		}
+		for _, k := range v1.MapKeys() {
+			val1 := v1.MapIndex(k)
+			val2 := v2.MapIndex(k)
+			if !val1.IsValid() || !val2.IsValid() || !deepValueEqual(val1, val2, visited) {
+				return false
+			}
+		}
+		return true
+	case Func:
+		if v1.IsNil() && v2.IsNil() {
+			return true
+		}
+		// Can't do better than this:
+		return false
+	case Int, Int8, Int16, Int32, Int64:
+		return v1.Int() == v2.Int()
+	case Uint, Uint8, Uint16, Uint32, Uint64, Uintptr:
+		return v1.Uint() == v2.Uint()
+	case String:
+		return v1.String() == v2.String()
+	case Bool:
+		return v1.Bool() == v2.Bool()
+	case Float32, Float64:
+		return v1.Float() == v2.Float()
+	case Complex64, Complex128:
+		return v1.Complex() == v2.Complex()
+	default:
+		// Normal equality suffices
+		return valueInterface(v1, false) == valueInterface(v2, false)
+	}
+}
+
+// DeepEqual reports whether x and y are “deeply equal,” defined as follows.
+// Two values of identical type are deeply equal if one of the following cases applies.
+// Values of distinct types are never deeply equal.
+//
+// Array values are deeply equal when their corresponding elements are deeply equal.
+//
+// Struct values are deeply equal if their corresponding fields,
+// both exported and unexported, are deeply equal.
+//
+// Func values are deeply equal if both are nil; otherwise they are not deeply equal.
+//
+// Interface values are deeply equal if they hold deeply equal concrete values.
+//
+// Map values are deeply equal when all of the following are true:
+// they are both nil or both non-nil, they have the same length,
+// and either they are the same map object or their corresponding keys
+// (matched using Go equality) map to deeply equal values.
+//
+// Pointer values are deeply equal if they are equal using Go's == operator
+// or if they point to deeply equal values.
+//
+// Slice values are deeply equal when all of the following are true:
+// they are both nil or both non-nil, they have the same length,
+// and either they point to the same initial entry of the same underlying array
+// (that is, &x[0] == &y[0]) or their corresponding elements (up to length) are deeply equal.
+// Note that a non-nil empty slice and a nil slice (for example, []byte{} and []byte(nil))
+// are not deeply equal.
+//
+// Other values - numbers, bools, strings, and channels - are deeply equal
+// if they are equal using Go's == operator.
+//
+// In general DeepEqual is a recursive relaxation of Go's == operator.
+// However, this idea is impossible to implement without some inconsistency.
+// Specifically, it is possible for a value to be unequal to itself,
+// either because it is of func type (uncomparable in general)
+// or because it is a floating-point NaN value (not equal to itself in floating-point comparison),
+// or because it is an array, struct, or interface containing
+// such a value.
+// On the other hand, pointer values are always equal to themselves,
+// even if they point at or contain such problematic values,
+// because they compare equal using Go's == operator, and that
+// is a sufficient condition to be deeply equal, regardless of content.
+// DeepEqual has been defined so that the same short-cut applies
+// to slices and maps: if x and y are the same slice or the same map,
+// they are deeply equal regardless of content.
+//
+// As DeepEqual traverses the data values it may find a cycle. The
+// second and subsequent times that DeepEqual compares two pointer
+// values that have been compared before, it treats the values as
+// equal rather than examining the values to which they point.
+// This ensures that DeepEqual terminates.
+func DeepEqual(x, y any) bool {
+	if x == nil || y == nil {
+		return x == y
+	}
+	v1 := ValueOf(x)
+	v2 := ValueOf(y)
+	if v1.Type() != v2.Type() {
+		return false
+	}
+	return deepValueEqual(v1, v2, make(map[visit]bool))
+}
diff --git a/contrib/go/_std_1.19/src/reflect/float32reg_generic.go b/contrib/go/_std_1.19/src/reflect/float32reg_generic.go
new file mode 100644
index 0000000000..23ad4bf285
--- /dev/null
+++ b/contrib/go/_std_1.19/src/reflect/float32reg_generic.go
@@ -0,0 +1,23 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !ppc64 && !ppc64le && !riscv64
+
+package reflect
+
+import "unsafe"
+
+// This file implements a straightforward conversion of a float32
+// value into its representation in a register. This conversion
+// applies for amd64 and arm64. It is also chosen for the case of
+// zero argument registers, but is not used.
+
+func archFloat32FromReg(reg uint64) float32 {
+	i := uint32(reg)
+	return *(*float32)(unsafe.Pointer(&i))
+}
+
+func archFloat32ToReg(val float32) uint64 {
+	return uint64(*(*uint32)(unsafe.Pointer(&val)))
+}
diff --git a/contrib/go/_std_1.19/src/reflect/makefunc.go b/contrib/go/_std_1.19/src/reflect/makefunc.go
new file mode 100644
index 0000000000..ee0729903e
--- /dev/null
+++ b/contrib/go/_std_1.19/src/reflect/makefunc.go
@@ -0,0 +1,176 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// MakeFunc implementation.
+
+package reflect
+
+import (
+	"internal/abi"
+	"unsafe"
+)
+
+// makeFuncImpl is the closure value implementing the function
+// returned by MakeFunc.
+// The first three words of this type must be kept in sync with
+// methodValue and runtime.reflectMethodValue.
+// Any changes should be reflected in all three.
+type makeFuncImpl struct {
+	makeFuncCtxt
+	ftyp *funcType
+	fn   func([]Value) []Value
+}
+
+// MakeFunc returns a new function of the given Type
+// that wraps the function fn. When called, that new function
+// does the following:
+//
+//   - converts its arguments to a slice of Values.
+//   - runs results := fn(args).
+//   - returns the results as a slice of Values, one per formal result.
+//
+// The implementation fn can assume that the argument Value slice
+// has the number and type of arguments given by typ.
+// If typ describes a variadic function, the final Value is itself
+// a slice representing the variadic arguments, as in the
+// body of a variadic function. The result Value slice returned by fn
+// must have the number and type of results given by typ.
+//
+// The Value.Call method allows the caller to invoke a typed function
+// in terms of Values; in contrast, MakeFunc allows the caller to implement
+// a typed function in terms of Values.
+//
+// The Examples section of the documentation includes an illustration
+// of how to use MakeFunc to build a swap function for different types.
+func MakeFunc(typ Type, fn func(args []Value) (results []Value)) Value {
+	if typ.Kind() != Func {
+		panic("reflect: call of MakeFunc with non-Func type")
+	}
+
+	t := typ.common()
+	ftyp := (*funcType)(unsafe.Pointer(t))
+
+	code := abi.FuncPCABI0(makeFuncStub)
+
+	// makeFuncImpl contains a stack map for use by the runtime
+	_, _, abid := funcLayout(ftyp, nil)
+
+	impl := &makeFuncImpl{
+		makeFuncCtxt: makeFuncCtxt{
+			fn:      code,
+			stack:   abid.stackPtrs,
+			argLen:  abid.stackCallArgsSize,
+			regPtrs: abid.inRegPtrs,
+		},
+		ftyp: ftyp,
+		fn:   fn,
+	}
+
+	return Value{t, unsafe.Pointer(impl), flag(Func)}
+}
+
+// makeFuncStub is an assembly function that is the code half of
+// the function returned from MakeFunc. It expects a *callReflectFunc
+// as its context register, and its job is to invoke callReflect(ctxt, frame)
+// where ctxt is the context register and frame is a pointer to the first
+// word in the passed-in argument frame.
+func makeFuncStub()
+
+// The first 3 words of this type must be kept in sync with
+// makeFuncImpl and runtime.reflectMethodValue.
+// Any changes should be reflected in all three.
+type methodValue struct {
+	makeFuncCtxt
+	method int
+	rcvr   Value
+}
+
+// makeMethodValue converts v from the rcvr+method index representation
+// of a method value to an actual method func value, which is
+// basically the receiver value with a special bit set, into a true
+// func value - a value holding an actual func. The output is
+// semantically equivalent to the input as far as the user of package
+// reflect can tell, but the true func representation can be handled
+// by code like Convert and Interface and Assign.
+func makeMethodValue(op string, v Value) Value {
+	if v.flag&flagMethod == 0 {
+		panic("reflect: internal error: invalid use of makeMethodValue")
+	}
+
+	// Ignoring the flagMethod bit, v describes the receiver, not the method type.
+	fl := v.flag & (flagRO | flagAddr | flagIndir)
+	fl |= flag(v.typ.Kind())
+	rcvr := Value{v.typ, v.ptr, fl}
+
+	// v.Type returns the actual type of the method value.
+	ftyp := (*funcType)(unsafe.Pointer(v.Type().(*rtype)))
+
+	code := methodValueCallCodePtr()
+
+	// methodValue contains a stack map for use by the runtime
+	_, _, abid := funcLayout(ftyp, nil)
+	fv := &methodValue{
+		makeFuncCtxt: makeFuncCtxt{
+			fn:      code,
+			stack:   abid.stackPtrs,
+			argLen:  abid.stackCallArgsSize,
+			regPtrs: abid.inRegPtrs,
+		},
+		method: int(v.flag) >> flagMethodShift,
+		rcvr:   rcvr,
+	}
+
+	// Cause panic if method is not appropriate.
+	// The panic would still happen during the call if we omit this,
+	// but we want Interface() and other operations to fail early.
+	methodReceiver(op, fv.rcvr, fv.method)
+
+	return Value{&ftyp.rtype, unsafe.Pointer(fv), v.flag&flagRO | flag(Func)}
+}
+
+func methodValueCallCodePtr() uintptr {
+	return abi.FuncPCABI0(methodValueCall)
+}
+
+// methodValueCall is an assembly function that is the code half of
+// the function returned from makeMethodValue. It expects a *methodValue
+// as its context register, and its job is to invoke callMethod(ctxt, frame)
+// where ctxt is the context register and frame is a pointer to the first
+// word in the passed-in argument frame.
+func methodValueCall()
+
+// This structure must be kept in sync with runtime.reflectMethodValue.
+// Any changes should be reflected in all both.
+type makeFuncCtxt struct {
+	fn      uintptr
+	stack   *bitVector // ptrmap for both stack args and results
+	argLen  uintptr    // just args
+	regPtrs abi.IntArgRegBitmap
+}
+
+// moveMakeFuncArgPtrs uses ctxt.regPtrs to copy integer pointer arguments
+// in args.Ints to args.Ptrs where the GC can see them.
+//
+// This is similar to what reflectcallmove does in the runtime, except
+// that happens on the return path, whereas this happens on the call path.
+//
+// nosplit because pointers are being held in uintptr slots in args, so
+// having our stack scanned now could lead to accidentally freeing
+// memory.
+//
+//go:nosplit
+func moveMakeFuncArgPtrs(ctxt *makeFuncCtxt, args *abi.RegArgs) {
+	for i, arg := range args.Ints {
+		// Avoid write barriers! Because our write barrier enqueues what
+		// was there before, we might enqueue garbage.
+		if ctxt.regPtrs.Get(i) {
+			*(*uintptr)(unsafe.Pointer(&args.Ptrs[i])) = arg
+		} else {
+			// We *must* zero this space ourselves because it's defined in
+			// assembly code and the GC will scan these pointers. Otherwise,
+			// there will be garbage here.
+			*(*uintptr)(unsafe.Pointer(&args.Ptrs[i])) = 0
+		}
+	}
+}
diff --git a/contrib/go/_std_1.18/src/reflect/swapper.go b/contrib/go/_std_1.19/src/reflect/swapper.go
index 745c7b9f49..745c7b9f49 100644
--- a/contrib/go/_std_1.18/src/reflect/swapper.go
+++ b/contrib/go/_std_1.19/src/reflect/swapper.go
diff --git a/contrib/go/_std_1.19/src/reflect/type.go b/contrib/go/_std_1.19/src/reflect/type.go
new file mode 100644
index 0000000000..a52d3129df
--- /dev/null
+++ b/contrib/go/_std_1.19/src/reflect/type.go
@@ -0,0 +1,3186 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package reflect implements run-time reflection, allowing a program to
+// manipulate objects with arbitrary types. The typical use is to take a value
+// with static type interface{} and extract its dynamic type information by
+// calling TypeOf, which returns a Type.
+//
+// A call to ValueOf returns a Value representing the run-time data.
+// Zero takes a Type and returns a Value representing a zero value
+// for that type.
+//
+// See "The Laws of Reflection" for an introduction to reflection in Go:
+// https://golang.org/doc/articles/laws_of_reflection.html
+package reflect
+
+import (
+	"internal/goarch"
+	"internal/unsafeheader"
+	"strconv"
+	"sync"
+	"unicode"
+	"unicode/utf8"
+	"unsafe"
+)
+
+// Type is the representation of a Go type.
+//
+// Not all methods apply to all kinds of types. Restrictions,
+// if any, are noted in the documentation for each method.
+// Use the Kind method to find out the kind of type before
+// calling kind-specific methods. Calling a method
+// inappropriate to the kind of type causes a run-time panic.
+//
+// Type values are comparable, such as with the == operator,
+// so they can be used as map keys.
+// Two Type values are equal if they represent identical types.
+type Type interface {
+	// Methods applicable to all types.
+
+	// Align returns the alignment in bytes of a value of
+	// this type when allocated in memory.
+	Align() int
+
+	// FieldAlign returns the alignment in bytes of a value of
+	// this type when used as a field in a struct.
+	FieldAlign() int
+
+	// Method returns the i'th method in the type's method set.
+	// It panics if i is not in the range [0, NumMethod()).
+	//
+	// For a non-interface type T or *T, the returned Method's Type and Func
+	// fields describe a function whose first argument is the receiver,
+	// and only exported methods are accessible.
+	//
+	// For an interface type, the returned Method's Type field gives the
+	// method signature, without a receiver, and the Func field is nil.
+	//
+	// Methods are sorted in lexicographic order.
+	Method(int) Method
+
+	// MethodByName returns the method with that name in the type's
+	// method set and a boolean indicating if the method was found.
+	//
+	// For a non-interface type T or *T, the returned Method's Type and Func
+	// fields describe a function whose first argument is the receiver.
+	//
+	// For an interface type, the returned Method's Type field gives the
+	// method signature, without a receiver, and the Func field is nil.
+	MethodByName(string) (Method, bool)
+
+	// NumMethod returns the number of methods accessible using Method.
+	//
+	// For a non-interface type, it returns the number of exported methods.
+	//
+	// For an interface type, it returns the number of exported and unexported methods.
+	NumMethod() int
+
+	// Name returns the type's name within its package for a defined type.
+	// For other (non-defined) types it returns the empty string.
+	Name() string
+
+	// PkgPath returns a defined type's package path, that is, the import path
+	// that uniquely identifies the package, such as "encoding/base64".
+	// If the type was predeclared (string, error) or not defined (*T, struct{},
+	// []int, or A where A is an alias for a non-defined type), the package path
+	// will be the empty string.
+	PkgPath() string
+
+	// Size returns the number of bytes needed to store
+	// a value of the given type; it is analogous to unsafe.Sizeof.
+	Size() uintptr
+
+	// String returns a string representation of the type.
+	// The string representation may use shortened package names
+	// (e.g., base64 instead of "encoding/base64") and is not
+	// guaranteed to be unique among types. To test for type identity,
+	// compare the Types directly.
+	String() string
+
+	// Kind returns the specific kind of this type.
+	Kind() Kind
+
+	// Implements reports whether the type implements the interface type u.
+	Implements(u Type) bool
+
+	// AssignableTo reports whether a value of the type is assignable to type u.
+	AssignableTo(u Type) bool
+
+	// ConvertibleTo reports whether a value of the type is convertible to type u.
+	// Even if ConvertibleTo returns true, the conversion may still panic.
+	// For example, a slice of type []T is convertible to *[N]T,
+	// but the conversion will panic if its length is less than N.
+	ConvertibleTo(u Type) bool
+
+	// Comparable reports whether values of this type are comparable.
+	// Even if Comparable returns true, the comparison may still panic.
+	// For example, values of interface type are comparable,
+	// but the comparison will panic if their dynamic type is not comparable.
+	Comparable() bool
+
+	// Methods applicable only to some types, depending on Kind.
+	// The methods allowed for each kind are:
+	//
+	//	Int*, Uint*, Float*, Complex*: Bits
+	//	Array: Elem, Len
+	//	Chan: ChanDir, Elem
+	//	Func: In, NumIn, Out, NumOut, IsVariadic.
+	//	Map: Key, Elem
+	//	Pointer: Elem
+	//	Slice: Elem
+	//	Struct: Field, FieldByIndex, FieldByName, FieldByNameFunc, NumField
+
+	// Bits returns the size of the type in bits.
+	// It panics if the type's Kind is not one of the
+	// sized or unsized Int, Uint, Float, or Complex kinds.
+	Bits() int
+
+	// ChanDir returns a channel type's direction.
+	// It panics if the type's Kind is not Chan.
+	ChanDir() ChanDir
+
+	// IsVariadic reports whether a function type's final input parameter
+	// is a "..." parameter. If so, t.In(t.NumIn() - 1) returns the parameter's
+	// implicit actual type []T.
+	//
+	// For concreteness, if t represents func(x int, y ... float64), then
+	//
+	//	t.NumIn() == 2
+	//	t.In(0) is the reflect.Type for "int"
+	//	t.In(1) is the reflect.Type for "[]float64"
+	//	t.IsVariadic() == true
+	//
+	// IsVariadic panics if the type's Kind is not Func.
+	IsVariadic() bool
+
+	// Elem returns a type's element type.
+	// It panics if the type's Kind is not Array, Chan, Map, Pointer, or Slice.
+	Elem() Type
+
+	// Field returns a struct type's i'th field.
+	// It panics if the type's Kind is not Struct.
+	// It panics if i is not in the range [0, NumField()).
+	Field(i int) StructField
+
+	// FieldByIndex returns the nested field corresponding
+	// to the index sequence. It is equivalent to calling Field
+	// successively for each index i.
+	// It panics if the type's Kind is not Struct.
+	FieldByIndex(index []int) StructField
+
+	// FieldByName returns the struct field with the given name
+	// and a boolean indicating if the field was found.
+	FieldByName(name string) (StructField, bool)
+
+	// FieldByNameFunc returns the struct field with a name
+	// that satisfies the match function and a boolean indicating if
+	// the field was found.
+	//
+	// FieldByNameFunc considers the fields in the struct itself
+	// and then the fields in any embedded structs, in breadth first order,
+	// stopping at the shallowest nesting depth containing one or more
+	// fields satisfying the match function. If multiple fields at that depth
+	// satisfy the match function, they cancel each other
+	// and FieldByNameFunc returns no match.
+	// This behavior mirrors Go's handling of name lookup in
+	// structs containing embedded fields.
+	FieldByNameFunc(match func(string) bool) (StructField, bool)
+
+	// In returns the type of a function type's i'th input parameter.
+	// It panics if the type's Kind is not Func.
+	// It panics if i is not in the range [0, NumIn()).
+	In(i int) Type
+
+	// Key returns a map type's key type.
+	// It panics if the type's Kind is not Map.
+	Key() Type
+
+	// Len returns an array type's length.
+	// It panics if the type's Kind is not Array.
+	Len() int
+
+	// NumField returns a struct type's field count.
+	// It panics if the type's Kind is not Struct.
+	NumField() int
+
+	// NumIn returns a function type's input parameter count.
+	// It panics if the type's Kind is not Func.
+	NumIn() int
+
+	// NumOut returns a function type's output parameter count.
+	// It panics if the type's Kind is not Func.
+	NumOut() int
+
+	// Out returns the type of a function type's i'th output parameter.
+	// It panics if the type's Kind is not Func.
+	// It panics if i is not in the range [0, NumOut()).
+	Out(i int) Type
+
+	common() *rtype
+	uncommon() *uncommonType
+}
+
+// BUG(rsc): FieldByName and related functions consider struct field names to be equal
+// if the names are equal, even if they are unexported names originating
+// in different packages. The practical effect of this is that the result of
+// t.FieldByName("x") is not well defined if the struct type t contains
+// multiple fields named x (embedded from different packages).
+// FieldByName may return one of the fields named x or may report that there are none.
+// See https://golang.org/issue/4876 for more details.
+
+/*
+ * These data structures are known to the compiler (../cmd/compile/internal/reflectdata/reflect.go).
+ * A few are known to ../runtime/type.go to convey to debuggers.
+ * They are also known to ../runtime/type.go.
+ */
+
+// A Kind represents the specific kind of type that a Type represents.
+// The zero Kind is not a valid kind.
+type Kind uint
+
+const (
+	Invalid Kind = iota
+	Bool
+	Int
+	Int8
+	Int16
+	Int32
+	Int64
+	Uint
+	Uint8
+	Uint16
+	Uint32
+	Uint64
+	Uintptr
+	Float32
+	Float64
+	Complex64
+	Complex128
+	Array
+	Chan
+	Func
+	Interface
+	Map
+	Pointer
+	Slice
+	String
+	Struct
+	UnsafePointer
+)
+
+// Ptr is the old name for the Pointer kind.
+const Ptr = Pointer
+
+// tflag is used by an rtype to signal what extra type information is
+// available in the memory directly following the rtype value.
+//
+// tflag values must be kept in sync with copies in:
+//
+//	cmd/compile/internal/reflectdata/reflect.go
+//	cmd/link/internal/ld/decodesym.go
+//	runtime/type.go
+type tflag uint8
+
+const (
+	// tflagUncommon means that there is a pointer, *uncommonType,
+	// just beyond the outer type structure.
+	//
+	// For example, if t.Kind() == Struct and t.tflag&tflagUncommon != 0,
+	// then t has uncommonType data and it can be accessed as:
+	//
+	//	type tUncommon struct {
+	//		structType
+	//		u uncommonType
+	//	}
+	//	u := &(*tUncommon)(unsafe.Pointer(t)).u
+	tflagUncommon tflag = 1 << 0
+
+	// tflagExtraStar means the name in the str field has an
+	// extraneous '*' prefix. This is because for most types T in
+	// a program, the type *T also exists and reusing the str data
+	// saves binary size.
+	tflagExtraStar tflag = 1 << 1
+
+	// tflagNamed means the type has a name.
+	tflagNamed tflag = 1 << 2
+
+	// tflagRegularMemory means that equal and hash functions can treat
+	// this type as a single region of t.size bytes.
+	tflagRegularMemory tflag = 1 << 3
+)
+
+// rtype is the common implementation of most values.
+// It is embedded in other struct types.
+//
+// rtype must be kept in sync with ../runtime/type.go:/^type._type.
+type rtype struct {
+	size       uintptr
+	ptrdata    uintptr // number of bytes in the type that can contain pointers
+	hash       uint32  // hash of type; avoids computation in hash tables
+	tflag      tflag   // extra type information flags
+	align      uint8   // alignment of variable with this type
+	fieldAlign uint8   // alignment of struct field with this type
+	kind       uint8   // enumeration for C
+	// function for comparing objects of this type
+	// (ptr to object A, ptr to object B) -> ==?
+	equal     func(unsafe.Pointer, unsafe.Pointer) bool
+	gcdata    *byte   // garbage collection data
+	str       nameOff // string form
+	ptrToThis typeOff // type for pointer to this type, may be zero
+}
+
+// Method on non-interface type
+type method struct {
+	name nameOff // name of method
+	mtyp typeOff // method type (without receiver)
+	ifn  textOff // fn used in interface call (one-word receiver)
+	tfn  textOff // fn used for normal method call
+}
+
+// uncommonType is present only for defined types or types with methods
+// (if T is a defined type, the uncommonTypes for T and *T have methods).
+// Using a pointer to this struct reduces the overall size required
+// to describe a non-defined type with no methods.
+type uncommonType struct {
+	pkgPath nameOff // import path; empty for built-in types like int, string
+	mcount  uint16  // number of methods
+	xcount  uint16  // number of exported methods
+	moff    uint32  // offset from this uncommontype to [mcount]method
+	_       uint32  // unused
+}
+
+// ChanDir represents a channel type's direction.
+type ChanDir int
+
+const (
+	RecvDir ChanDir             = 1 << iota // <-chan
+	SendDir                                 // chan<-
+	BothDir = RecvDir | SendDir             // chan
+)
+
+// arrayType represents a fixed array type.
+type arrayType struct {
+	rtype
+	elem  *rtype // array element type
+	slice *rtype // slice type
+	len   uintptr
+}
+
+// chanType represents a channel type.
+type chanType struct {
+	rtype
+	elem *rtype  // channel element type
+	dir  uintptr // channel direction (ChanDir)
+}
+
+// funcType represents a function type.
+//
+// A *rtype for each in and out parameter is stored in an array that
+// directly follows the funcType (and possibly its uncommonType). So
+// a function type with one method, one input, and one output is:
+//
+//	struct {
+//		funcType
+//		uncommonType
+//		[2]*rtype    // [0] is in, [1] is out
+//	}
+type funcType struct {
+	rtype
+	inCount  uint16
+	outCount uint16 // top bit is set if last input parameter is ...
+}
+
+// imethod represents a method on an interface type
+type imethod struct {
+	name nameOff // name of method
+	typ  typeOff // .(*FuncType) underneath
+}
+
+// interfaceType represents an interface type.
+type interfaceType struct {
+	rtype
+	pkgPath name      // import path
+	methods []imethod // sorted by hash
+}
+
+// mapType represents a map type.
+type mapType struct {
+	rtype
+	key    *rtype // map key type
+	elem   *rtype // map element (value) type
+	bucket *rtype // internal bucket structure
+	// function for hashing keys (ptr to key, seed) -> hash
+	hasher     func(unsafe.Pointer, uintptr) uintptr
+	keysize    uint8  // size of key slot
+	valuesize  uint8  // size of value slot
+	bucketsize uint16 // size of bucket
+	flags      uint32
+}
+
+// ptrType represents a pointer type.
+type ptrType struct {
+	rtype
+	elem *rtype // pointer element (pointed at) type
+}
+
+// sliceType represents a slice type.
+type sliceType struct {
+	rtype
+	elem *rtype // slice element type
+}
+
+// Struct field
+type structField struct {
+	name   name    // name is always non-empty
+	typ    *rtype  // type of field
+	offset uintptr // byte offset of field
+}
+
+func (f *structField) embedded() bool {
+	return f.name.embedded()
+}
+
+// structType represents a struct type.
+type structType struct {
+	rtype
+	pkgPath name
+	fields  []structField // sorted by offset
+}
+
+// name is an encoded type name with optional extra data.
+//
+// The first byte is a bit field containing:
+//
+//	1<<0 the name is exported
+//	1<<1 tag data follows the name
+//	1<<2 pkgPath nameOff follows the name and tag
+//	1<<3 the name is of an embedded (a.k.a. anonymous) field
+//
+// Following that, there is a varint-encoded length of the name,
+// followed by the name itself.
+//
+// If tag data is present, it also has a varint-encoded length
+// followed by the tag itself.
+//
+// If the import path follows, then 4 bytes at the end of
+// the data form a nameOff. The import path is only set for concrete
+// methods that are defined in a different package than their type.
+//
+// If a name starts with "*", then the exported bit represents
+// whether the pointed to type is exported.
+//
+// Note: this encoding must match here and in:
+//   cmd/compile/internal/reflectdata/reflect.go
+//   runtime/type.go
+//   internal/reflectlite/type.go
+//   cmd/link/internal/ld/decodesym.go
+
+type name struct {
+	bytes *byte
+}
+
+func (n name) data(off int, whySafe string) *byte {
+	return (*byte)(add(unsafe.Pointer(n.bytes), uintptr(off), whySafe))
+}
+
+func (n name) isExported() bool {
+	return (*n.bytes)&(1<<0) != 0
+}
+
+func (n name) hasTag() bool {
+	return (*n.bytes)&(1<<1) != 0
+}
+
+func (n name) embedded() bool {
+	return (*n.bytes)&(1<<3) != 0
+}
+
+// readVarint parses a varint as encoded by encoding/binary.
+// It returns the number of encoded bytes and the encoded value.
+func (n name) readVarint(off int) (int, int) {
+	v := 0
+	for i := 0; ; i++ {
+		x := *n.data(off+i, "read varint")
+		v += int(x&0x7f) << (7 * i)
+		if x&0x80 == 0 {
+			return i + 1, v
+		}
+	}
+}
+
+// writeVarint writes n to buf in varint form. Returns the
+// number of bytes written. n must be nonnegative.
+// Writes at most 10 bytes.
+func writeVarint(buf []byte, n int) int {
+	for i := 0; ; i++ {
+		b := byte(n & 0x7f)
+		n >>= 7
+		if n == 0 {
+			buf[i] = b
+			return i + 1
+		}
+		buf[i] = b | 0x80
+	}
+}
+
+func (n name) name() (s string) {
+	if n.bytes == nil {
+		return
+	}
+	i, l := n.readVarint(1)
+	hdr := (*unsafeheader.String)(unsafe.Pointer(&s))
+	hdr.Data = unsafe.Pointer(n.data(1+i, "non-empty string"))
+	hdr.Len = l
+	return
+}
+
+func (n name) tag() (s string) {
+	if !n.hasTag() {
+		return ""
+	}
+	i, l := n.readVarint(1)
+	i2, l2 := n.readVarint(1 + i + l)
+	hdr := (*unsafeheader.String)(unsafe.Pointer(&s))
+	hdr.Data = unsafe.Pointer(n.data(1+i+l+i2, "non-empty string"))
+	hdr.Len = l2
+	return
+}
+
+func (n name) pkgPath() string {
+	if n.bytes == nil || *n.data(0, "name flag field")&(1<<2) == 0 {
+		return ""
+	}
+	i, l := n.readVarint(1)
+	off := 1 + i + l
+	if n.hasTag() {
+		i2, l2 := n.readVarint(off)
+		off += i2 + l2
+	}
+	var nameOff int32
+	// Note that this field may not be aligned in memory,
+	// so we cannot use a direct int32 assignment here.
+	copy((*[4]byte)(unsafe.Pointer(&nameOff))[:], (*[4]byte)(unsafe.Pointer(n.data(off, "name offset field")))[:])
+	pkgPathName := name{(*byte)(resolveTypeOff(unsafe.Pointer(n.bytes), nameOff))}
+	return pkgPathName.name()
+}
+
+func newName(n, tag string, exported, embedded bool) name {
+	if len(n) >= 1<<29 {
+		panic("reflect.nameFrom: name too long: " + n[:1024] + "...")
+	}
+	if len(tag) >= 1<<29 {
+		panic("reflect.nameFrom: tag too long: " + tag[:1024] + "...")
+	}
+	var nameLen [10]byte
+	var tagLen [10]byte
+	nameLenLen := writeVarint(nameLen[:], len(n))
+	tagLenLen := writeVarint(tagLen[:], len(tag))
+
+	var bits byte
+	l := 1 + nameLenLen + len(n)
+	if exported {
+		bits |= 1 << 0
+	}
+	if len(tag) > 0 {
+		l += tagLenLen + len(tag)
+		bits |= 1 << 1
+	}
+	if embedded {
+		bits |= 1 << 3
+	}
+
+	b := make([]byte, l)
+	b[0] = bits
+	copy(b[1:], nameLen[:nameLenLen])
+	copy(b[1+nameLenLen:], n)
+	if len(tag) > 0 {
+		tb := b[1+nameLenLen+len(n):]
+		copy(tb, tagLen[:tagLenLen])
+		copy(tb[tagLenLen:], tag)
+	}
+
+	return name{bytes: &b[0]}
+}
+
+/*
+ * The compiler knows the exact layout of all the data structures above.
+ * The compiler does not know about the data structures and methods below.
+ */
+
+// Method represents a single method.
+type Method struct {
+	// Name is the method name.
+	Name string
+
+	// PkgPath is the package path that qualifies a lower case (unexported)
+	// method name. It is empty for upper case (exported) method names.
+	// The combination of PkgPath and Name uniquely identifies a method
+	// in a method set.
+	// See https://golang.org/ref/spec#Uniqueness_of_identifiers
+	PkgPath string
+
+	Type  Type  // method type
+	Func  Value // func with receiver as first argument
+	Index int   // index for Type.Method
+}
+
+// IsExported reports whether the method is exported.
+func (m Method) IsExported() bool {
+	return m.PkgPath == ""
+}
+
+const (
+	kindDirectIface = 1 << 5
+	kindGCProg      = 1 << 6 // Type.gc points to GC program
+	kindMask        = (1 << 5) - 1
+)
+
+// String returns the name of k.
+func (k Kind) String() string {
+	if uint(k) < uint(len(kindNames)) {
+		return kindNames[uint(k)]
+	}
+	return "kind" + strconv.Itoa(int(k))
+}
+
+var kindNames = []string{
+	Invalid:       "invalid",
+	Bool:          "bool",
+	Int:           "int",
+	Int8:          "int8",
+	Int16:         "int16",
+	Int32:         "int32",
+	Int64:         "int64",
+	Uint:          "uint",
+	Uint8:         "uint8",
+	Uint16:        "uint16",
+	Uint32:        "uint32",
+	Uint64:        "uint64",
+	Uintptr:       "uintptr",
+	Float32:       "float32",
+	Float64:       "float64",
+	Complex64:     "complex64",
+	Complex128:    "complex128",
+	Array:         "array",
+	Chan:          "chan",
+	Func:          "func",
+	Interface:     "interface",
+	Map:           "map",
+	Pointer:       "ptr",
+	Slice:         "slice",
+	String:        "string",
+	Struct:        "struct",
+	UnsafePointer: "unsafe.Pointer",
+}
+
+func (t *uncommonType) methods() []method {
+	if t.mcount == 0 {
+		return nil
+	}
+	return (*[1 << 16]method)(add(unsafe.Pointer(t), uintptr(t.moff), "t.mcount > 0"))[:t.mcount:t.mcount]
+}
+
+func (t *uncommonType) exportedMethods() []method {
+	if t.xcount == 0 {
+		return nil
+	}
+	return (*[1 << 16]method)(add(unsafe.Pointer(t), uintptr(t.moff), "t.xcount > 0"))[:t.xcount:t.xcount]
+}
+
+// resolveNameOff resolves a name offset from a base pointer.
+// The (*rtype).nameOff method is a convenience wrapper for this function.
+// Implemented in the runtime package.
+func resolveNameOff(ptrInModule unsafe.Pointer, off int32) unsafe.Pointer
+
+// resolveTypeOff resolves an *rtype offset from a base type.
+// The (*rtype).typeOff method is a convenience wrapper for this function.
+// Implemented in the runtime package.
+func resolveTypeOff(rtype unsafe.Pointer, off int32) unsafe.Pointer
+
+// resolveTextOff resolves a function pointer offset from a base type.
+// The (*rtype).textOff method is a convenience wrapper for this function.
+// Implemented in the runtime package.
+func resolveTextOff(rtype unsafe.Pointer, off int32) unsafe.Pointer
+
+// addReflectOff adds a pointer to the reflection lookup map in the runtime.
+// It returns a new ID that can be used as a typeOff or textOff, and will
+// be resolved correctly. Implemented in the runtime package.
+func addReflectOff(ptr unsafe.Pointer) int32
+
+// resolveReflectName adds a name to the reflection lookup map in the runtime.
+// It returns a new nameOff that can be used to refer to the pointer.
+func resolveReflectName(n name) nameOff {
+	return nameOff(addReflectOff(unsafe.Pointer(n.bytes)))
+}
+
+// resolveReflectType adds a *rtype to the reflection lookup map in the runtime.
+// It returns a new typeOff that can be used to refer to the pointer.
+func resolveReflectType(t *rtype) typeOff {
+	return typeOff(addReflectOff(unsafe.Pointer(t)))
+}
+
+// resolveReflectText adds a function pointer to the reflection lookup map in
+// the runtime. It returns a new textOff that can be used to refer to the
+// pointer.
+func resolveReflectText(ptr unsafe.Pointer) textOff {
+	return textOff(addReflectOff(ptr))
+}
+
+type nameOff int32 // offset to a name
+type typeOff int32 // offset to an *rtype
+type textOff int32 // offset from top of text section
+
+func (t *rtype) nameOff(off nameOff) name {
+	return name{(*byte)(resolveNameOff(unsafe.Pointer(t), int32(off)))}
+}
+
+func (t *rtype) typeOff(off typeOff) *rtype {
+	return (*rtype)(resolveTypeOff(unsafe.Pointer(t), int32(off)))
+}
+
+func (t *rtype) textOff(off textOff) unsafe.Pointer {
+	return resolveTextOff(unsafe.Pointer(t), int32(off))
+}
+
+func (t *rtype) uncommon() *uncommonType {
+	if t.tflag&tflagUncommon == 0 {
+		return nil
+	}
+	switch t.Kind() {
+	case Struct:
+		return &(*structTypeUncommon)(unsafe.Pointer(t)).u
+	case Pointer:
+		type u struct {
+			ptrType
+			u uncommonType
+		}
+		return &(*u)(unsafe.Pointer(t)).u
+	case Func:
+		type u struct {
+			funcType
+			u uncommonType
+		}
+		return &(*u)(unsafe.Pointer(t)).u
+	case Slice:
+		type u struct {
+			sliceType
+			u uncommonType
+		}
+		return &(*u)(unsafe.Pointer(t)).u
+	case Array:
+		type u struct {
+			arrayType
+			u uncommonType
+		}
+		return &(*u)(unsafe.Pointer(t)).u
+	case Chan:
+		type u struct {
+			chanType
+			u uncommonType
+		}
+		return &(*u)(unsafe.Pointer(t)).u
+	case Map:
+		type u struct {
+			mapType
+			u uncommonType
+		}
+		return &(*u)(unsafe.Pointer(t)).u
+	case Interface:
+		type u struct {
+			interfaceType
+			u uncommonType
+		}
+		return &(*u)(unsafe.Pointer(t)).u
+	default:
+		type u struct {
+			rtype
+			u uncommonType
+		}
+		return &(*u)(unsafe.Pointer(t)).u
+	}
+}
+
+func (t *rtype) String() string {
+	s := t.nameOff(t.str).name()
+	if t.tflag&tflagExtraStar != 0 {
+		return s[1:]
+	}
+	return s
+}
+
+func (t *rtype) Size() uintptr { return t.size }
+
+func (t *rtype) Bits() int {
+	if t == nil {
+		panic("reflect: Bits of nil Type")
+	}
+	k := t.Kind()
+	if k < Int || k > Complex128 {
+		panic("reflect: Bits of non-arithmetic Type " + t.String())
+	}
+	return int(t.size) * 8
+}
+
+func (t *rtype) Align() int { return int(t.align) }
+
+func (t *rtype) FieldAlign() int { return int(t.fieldAlign) }
+
+func (t *rtype) Kind() Kind { return Kind(t.kind & kindMask) }
+
+func (t *rtype) pointers() bool { return t.ptrdata != 0 }
+
+func (t *rtype) common() *rtype { return t }
+
+func (t *rtype) exportedMethods() []method {
+	ut := t.uncommon()
+	if ut == nil {
+		return nil
+	}
+	return ut.exportedMethods()
+}
+
+func (t *rtype) NumMethod() int {
+	if t.Kind() == Interface {
+		tt := (*interfaceType)(unsafe.Pointer(t))
+		return tt.NumMethod()
+	}
+	return len(t.exportedMethods())
+}
+
+func (t *rtype) Method(i int) (m Method) {
+	if t.Kind() == Interface {
+		tt := (*interfaceType)(unsafe.Pointer(t))
+		return tt.Method(i)
+	}
+	methods := t.exportedMethods()
+	if i < 0 || i >= len(methods) {
+		panic("reflect: Method index out of range")
+	}
+	p := methods[i]
+	pname := t.nameOff(p.name)
+	m.Name = pname.name()
+	fl := flag(Func)
+	mtyp := t.typeOff(p.mtyp)
+	ft := (*funcType)(unsafe.Pointer(mtyp))
+	in := make([]Type, 0, 1+len(ft.in()))
+	in = append(in, t)
+	for _, arg := range ft.in() {
+		in = append(in, arg)
+	}
+	out := make([]Type, 0, len(ft.out()))
+	for _, ret := range ft.out() {
+		out = append(out, ret)
+	}
+	mt := FuncOf(in, out, ft.IsVariadic())
+	m.Type = mt
+	tfn := t.textOff(p.tfn)
+	fn := unsafe.Pointer(&tfn)
+	m.Func = Value{mt.(*rtype), fn, fl}
+
+	m.Index = i
+	return m
+}
+
+func (t *rtype) MethodByName(name string) (m Method, ok bool) {
+	if t.Kind() == Interface {
+		tt := (*interfaceType)(unsafe.Pointer(t))
+		return tt.MethodByName(name)
+	}
+	ut := t.uncommon()
+	if ut == nil {
+		return Method{}, false
+	}
+	// TODO(mdempsky): Binary search.
+	for i, p := range ut.exportedMethods() {
+		if t.nameOff(p.name).name() == name {
+			return t.Method(i), true
+		}
+	}
+	return Method{}, false
+}
+
+func (t *rtype) PkgPath() string {
+	if t.tflag&tflagNamed == 0 {
+		return ""
+	}
+	ut := t.uncommon()
+	if ut == nil {
+		return ""
+	}
+	return t.nameOff(ut.pkgPath).name()
+}
+
+func (t *rtype) hasName() bool {
+	return t.tflag&tflagNamed != 0
+}
+
+func (t *rtype) Name() string {
+	if !t.hasName() {
+		return ""
+	}
+	s := t.String()
+	i := len(s) - 1
+	sqBrackets := 0
+	for i >= 0 && (s[i] != '.' || sqBrackets != 0) {
+		switch s[i] {
+		case ']':
+			sqBrackets++
+		case '[':
+			sqBrackets--
+		}
+		i--
+	}
+	return s[i+1:]
+}
+
+func (t *rtype) ChanDir() ChanDir {
+	if t.Kind() != Chan {
+		panic("reflect: ChanDir of non-chan type " + t.String())
+	}
+	tt := (*chanType)(unsafe.Pointer(t))
+	return ChanDir(tt.dir)
+}
+
+func (t *rtype) IsVariadic() bool {
+	if t.Kind() != Func {
+		panic("reflect: IsVariadic of non-func type " + t.String())
+	}
+	tt := (*funcType)(unsafe.Pointer(t))
+	return tt.outCount&(1<<15) != 0
+}
+
+func (t *rtype) Elem() Type {
+	switch t.Kind() {
+	case Array:
+		tt := (*arrayType)(unsafe.Pointer(t))
+		return toType(tt.elem)
+	case Chan:
+		tt := (*chanType)(unsafe.Pointer(t))
+		return toType(tt.elem)
+	case Map:
+		tt := (*mapType)(unsafe.Pointer(t))
+		return toType(tt.elem)
+	case Pointer:
+		tt := (*ptrType)(unsafe.Pointer(t))
+		return toType(tt.elem)
+	case Slice:
+		tt := (*sliceType)(unsafe.Pointer(t))
+		return toType(tt.elem)
+	}
+	panic("reflect: Elem of invalid type " + t.String())
+}
+
+func (t *rtype) Field(i int) StructField {
+	if t.Kind() != Struct {
+		panic("reflect: Field of non-struct type " + t.String())
+	}
+	tt := (*structType)(unsafe.Pointer(t))
+	return tt.Field(i)
+}
+
+func (t *rtype) FieldByIndex(index []int) StructField {
+	if t.Kind() != Struct {
+		panic("reflect: FieldByIndex of non-struct type " + t.String())
+	}
+	tt := (*structType)(unsafe.Pointer(t))
+	return tt.FieldByIndex(index)
+}
+
+func (t *rtype) FieldByName(name string) (StructField, bool) {
+	if t.Kind() != Struct {
+		panic("reflect: FieldByName of non-struct type " + t.String())
+	}
+	tt := (*structType)(unsafe.Pointer(t))
+	return tt.FieldByName(name)
+}
+
+func (t *rtype) FieldByNameFunc(match func(string) bool) (StructField, bool) {
+	if t.Kind() != Struct {
+		panic("reflect: FieldByNameFunc of non-struct type " + t.String())
+	}
+	tt := (*structType)(unsafe.Pointer(t))
+	return tt.FieldByNameFunc(match)
+}
+
+func (t *rtype) In(i int) Type {
+	if t.Kind() != Func {
+		panic("reflect: In of non-func type " + t.String())
+	}
+	tt := (*funcType)(unsafe.Pointer(t))
+	return toType(tt.in()[i])
+}
+
+func (t *rtype) Key() Type {
+	if t.Kind() != Map {
+		panic("reflect: Key of non-map type " + t.String())
+	}
+	tt := (*mapType)(unsafe.Pointer(t))
+	return toType(tt.key)
+}
+
+func (t *rtype) Len() int {
+	if t.Kind() != Array {
+		panic("reflect: Len of non-array type " + t.String())
+	}
+	tt := (*arrayType)(unsafe.Pointer(t))
+	return int(tt.len)
+}
+
+func (t *rtype) NumField() int {
+	if t.Kind() != Struct {
+		panic("reflect: NumField of non-struct type " + t.String())
+	}
+	tt := (*structType)(unsafe.Pointer(t))
+	return len(tt.fields)
+}
+
+func (t *rtype) NumIn() int {
+	if t.Kind() != Func {
+		panic("reflect: NumIn of non-func type " + t.String())
+	}
+	tt := (*funcType)(unsafe.Pointer(t))
+	return int(tt.inCount)
+}
+
+func (t *rtype) NumOut() int {
+	if t.Kind() != Func {
+		panic("reflect: NumOut of non-func type " + t.String())
+	}
+	tt := (*funcType)(unsafe.Pointer(t))
+	return len(tt.out())
+}
+
+func (t *rtype) Out(i int) Type {
+	if t.Kind() != Func {
+		panic("reflect: Out of non-func type " + t.String())
+	}
+	tt := (*funcType)(unsafe.Pointer(t))
+	return toType(tt.out()[i])
+}
+
+func (t *funcType) in() []*rtype {
+	uadd := unsafe.Sizeof(*t)
+	if t.tflag&tflagUncommon != 0 {
+		uadd += unsafe.Sizeof(uncommonType{})
+	}
+	if t.inCount == 0 {
+		return nil
+	}
+	return (*[1 << 20]*rtype)(add(unsafe.Pointer(t), uadd, "t.inCount > 0"))[:t.inCount:t.inCount]
+}
+
+func (t *funcType) out() []*rtype {
+	uadd := unsafe.Sizeof(*t)
+	if t.tflag&tflagUncommon != 0 {
+		uadd += unsafe.Sizeof(uncommonType{})
+	}
+	outCount := t.outCount & (1<<15 - 1)
+	if outCount == 0 {
+		return nil
+	}
+	return (*[1 << 20]*rtype)(add(unsafe.Pointer(t), uadd, "outCount > 0"))[t.inCount : t.inCount+outCount : t.inCount+outCount]
+}
+
+// add returns p+x.
+//
+// The whySafe string is ignored, so that the function still inlines
+// as efficiently as p+x, but all call sites should use the string to
+// record why the addition is safe, which is to say why the addition
+// does not cause x to advance to the very end of p's allocation
+// and therefore point incorrectly at the next block in memory.
+func add(p unsafe.Pointer, x uintptr, whySafe string) unsafe.Pointer {
+	return unsafe.Pointer(uintptr(p) + x)
+}
+
+func (d ChanDir) String() string {
+	switch d {
+	case SendDir:
+		return "chan<-"
+	case RecvDir:
+		return "<-chan"
+	case BothDir:
+		return "chan"
+	}
+	return "ChanDir" + strconv.Itoa(int(d))
+}
+
+// Method returns the i'th method in the type's method set.
+func (t *interfaceType) Method(i int) (m Method) {
+	if i < 0 || i >= len(t.methods) {
+		return
+	}
+	p := &t.methods[i]
+	pname := t.nameOff(p.name)
+	m.Name = pname.name()
+	if !pname.isExported() {
+		m.PkgPath = pname.pkgPath()
+		if m.PkgPath == "" {
+			m.PkgPath = t.pkgPath.name()
+		}
+	}
+	m.Type = toType(t.typeOff(p.typ))
+	m.Index = i
+	return
+}
+
+// NumMethod returns the number of interface methods in the type's method set.
+func (t *interfaceType) NumMethod() int { return len(t.methods) }
+
+// MethodByName method with the given name in the type's method set.
+func (t *interfaceType) MethodByName(name string) (m Method, ok bool) {
+	if t == nil {
+		return
+	}
+	var p *imethod
+	for i := range t.methods {
+		p = &t.methods[i]
+		if t.nameOff(p.name).name() == name {
+			return t.Method(i), true
+		}
+	}
+	return
+}
+
+// A StructField describes a single field in a struct.
+type StructField struct {
+	// Name is the field name.
+	Name string
+
+	// PkgPath is the package path that qualifies a lower case (unexported)
+	// field name. It is empty for upper case (exported) field names.
+	// See https://golang.org/ref/spec#Uniqueness_of_identifiers
+	PkgPath string
+
+	Type      Type      // field type
+	Tag       StructTag // field tag string
+	Offset    uintptr   // offset within struct, in bytes
+	Index     []int     // index sequence for Type.FieldByIndex
+	Anonymous bool      // is an embedded field
+}
+
+// IsExported reports whether the field is exported.
+func (f StructField) IsExported() bool {
+	return f.PkgPath == ""
+}
+
+// A StructTag is the tag string in a struct field.
+//
+// By convention, tag strings are a concatenation of
+// optionally space-separated key:"value" pairs.
+// Each key is a non-empty string consisting of non-control
+// characters other than space (U+0020 ' '), quote (U+0022 '"'),
+// and colon (U+003A ':').  Each value is quoted using U+0022 '"'
+// characters and Go string literal syntax.
+type StructTag string
+
+// Get returns the value associated with key in the tag string.
+// If there is no such key in the tag, Get returns the empty string.
+// If the tag does not have the conventional format, the value
+// returned by Get is unspecified. To determine whether a tag is
+// explicitly set to the empty string, use Lookup.
+func (tag StructTag) Get(key string) string {
+	v, _ := tag.Lookup(key)
+	return v
+}
+
+// Lookup returns the value associated with key in the tag string.
+// If the key is present in the tag the value (which may be empty)
+// is returned. Otherwise the returned value will be the empty string.
+// The ok return value reports whether the value was explicitly set in
+// the tag string. If the tag does not have the conventional format,
+// the value returned by Lookup is unspecified.
+func (tag StructTag) Lookup(key string) (value string, ok bool) {
+	// When modifying this code, also update the validateStructTag code
+	// in cmd/vet/structtag.go.
+
+	for tag != "" {
+		// Skip leading space.
+		i := 0
+		for i < len(tag) && tag[i] == ' ' {
+			i++
+		}
+		tag = tag[i:]
+		if tag == "" {
+			break
+		}
+
+		// Scan to colon. A space, a quote or a control character is a syntax error.
+		// Strictly speaking, control chars include the range [0x7f, 0x9f], not just
+		// [0x00, 0x1f], but in practice, we ignore the multi-byte control characters
+		// as it is simpler to inspect the tag's bytes than the tag's runes.
+		i = 0
+		for i < len(tag) && tag[i] > ' ' && tag[i] != ':' && tag[i] != '"' && tag[i] != 0x7f {
+			i++
+		}
+		if i == 0 || i+1 >= len(tag) || tag[i] != ':' || tag[i+1] != '"' {
+			break
+		}
+		name := string(tag[:i])
+		tag = tag[i+1:]
+
+		// Scan quoted string to find value.
+		i = 1
+		for i < len(tag) && tag[i] != '"' {
+			if tag[i] == '\\' {
+				i++
+			}
+			i++
+		}
+		if i >= len(tag) {
+			break
+		}
+		qvalue := string(tag[:i+1])
+		tag = tag[i+1:]
+
+		if key == name {
+			value, err := strconv.Unquote(qvalue)
+			if err != nil {
+				break
+			}
+			return value, true
+		}
+	}
+	return "", false
+}
+
+// Field returns the i'th struct field.
+func (t *structType) Field(i int) (f StructField) {
+	if i < 0 || i >= len(t.fields) {
+		panic("reflect: Field index out of bounds")
+	}
+	p := &t.fields[i]
+	f.Type = toType(p.typ)
+	f.Name = p.name.name()
+	f.Anonymous = p.embedded()
+	if !p.name.isExported() {
+		f.PkgPath = t.pkgPath.name()
+	}
+	if tag := p.name.tag(); tag != "" {
+		f.Tag = StructTag(tag)
+	}
+	f.Offset = p.offset
+
+	// NOTE(rsc): This is the only allocation in the interface
+	// presented by a reflect.Type. It would be nice to avoid,
+	// at least in the common cases, but we need to make sure
+	// that misbehaving clients of reflect cannot affect other
+	// uses of reflect. One possibility is CL 5371098, but we
+	// postponed that ugliness until there is a demonstrated
+	// need for the performance. This is issue 2320.
+	f.Index = []int{i}
+	return
+}
+
+// TODO(gri): Should there be an error/bool indicator if the index
+// is wrong for FieldByIndex?
+
+// FieldByIndex returns the nested field corresponding to index.
+func (t *structType) FieldByIndex(index []int) (f StructField) {
+	f.Type = toType(&t.rtype)
+	for i, x := range index {
+		if i > 0 {
+			ft := f.Type
+			if ft.Kind() == Pointer && ft.Elem().Kind() == Struct {
+				ft = ft.Elem()
+			}
+			f.Type = ft
+		}
+		f = f.Type.Field(x)
+	}
+	return
+}
+
+// A fieldScan represents an item on the fieldByNameFunc scan work list.
+type fieldScan struct {
+	typ   *structType
+	index []int
+}
+
+// FieldByNameFunc returns the struct field with a name that satisfies the
+// match function and a boolean to indicate if the field was found.
+func (t *structType) FieldByNameFunc(match func(string) bool) (result StructField, ok bool) {
+	// This uses the same condition that the Go language does: there must be a unique instance
+	// of the match at a given depth level. If there are multiple instances of a match at the
+	// same depth, they annihilate each other and inhibit any possible match at a lower level.
+	// The algorithm is breadth first search, one depth level at a time.
+
+	// The current and next slices are work queues:
+	// current lists the fields to visit on this depth level,
+	// and next lists the fields on the next lower level.
+	current := []fieldScan{}
+	next := []fieldScan{{typ: t}}
+
+	// nextCount records the number of times an embedded type has been
+	// encountered and considered for queueing in the 'next' slice.
+	// We only queue the first one, but we increment the count on each.
+	// If a struct type T can be reached more than once at a given depth level,
+	// then it annihilates itself and need not be considered at all when we
+	// process that next depth level.
+	var nextCount map[*structType]int
+
+	// visited records the structs that have been considered already.
+	// Embedded pointer fields can create cycles in the graph of
+	// reachable embedded types; visited avoids following those cycles.
+	// It also avoids duplicated effort: if we didn't find the field in an
+	// embedded type T at level 2, we won't find it in one at level 4 either.
+	visited := map[*structType]bool{}
+
+	for len(next) > 0 {
+		current, next = next, current[:0]
+		count := nextCount
+		nextCount = nil
+
+		// Process all the fields at this depth, now listed in 'current'.
+		// The loop queues embedded fields found in 'next', for processing during the next
+		// iteration. The multiplicity of the 'current' field counts is recorded
+		// in 'count'; the multiplicity of the 'next' field counts is recorded in 'nextCount'.
+		for _, scan := range current {
+			t := scan.typ
+			if visited[t] {
+				// We've looked through this type before, at a higher level.
+				// That higher level would shadow the lower level we're now at,
+				// so this one can't be useful to us. Ignore it.
+				continue
+			}
+			visited[t] = true
+			for i := range t.fields {
+				f := &t.fields[i]
+				// Find name and (for embedded field) type for field f.
+				fname := f.name.name()
+				var ntyp *rtype
+				if f.embedded() {
+					// Embedded field of type T or *T.
+					ntyp = f.typ
+					if ntyp.Kind() == Pointer {
+						ntyp = ntyp.Elem().common()
+					}
+				}
+
+				// Does it match?
+				if match(fname) {
+					// Potential match
+					if count[t] > 1 || ok {
+						// Name appeared multiple times at this level: annihilate.
+						return StructField{}, false
+					}
+					result = t.Field(i)
+					result.Index = nil
+					result.Index = append(result.Index, scan.index...)
+					result.Index = append(result.Index, i)
+					ok = true
+					continue
+				}
+
+				// Queue embedded struct fields for processing with next level,
+				// but only if we haven't seen a match yet at this level and only
+				// if the embedded types haven't already been queued.
+				if ok || ntyp == nil || ntyp.Kind() != Struct {
+					continue
+				}
+				styp := (*structType)(unsafe.Pointer(ntyp))
+				if nextCount[styp] > 0 {
+					nextCount[styp] = 2 // exact multiple doesn't matter
+					continue
+				}
+				if nextCount == nil {
+					nextCount = map[*structType]int{}
+				}
+				nextCount[styp] = 1
+				if count[t] > 1 {
+					nextCount[styp] = 2 // exact multiple doesn't matter
+				}
+				var index []int
+				index = append(index, scan.index...)
+				index = append(index, i)
+				next = append(next, fieldScan{styp, index})
+			}
+		}
+		if ok {
+			break
+		}
+	}
+	return
+}
+
+// FieldByName returns the struct field with the given name
+// and a boolean to indicate if the field was found.
+func (t *structType) FieldByName(name string) (f StructField, present bool) {
+	// Quick check for top-level name, or struct without embedded fields.
+	hasEmbeds := false
+	if name != "" {
+		for i := range t.fields {
+			tf := &t.fields[i]
+			if tf.name.name() == name {
+				return t.Field(i), true
+			}
+			if tf.embedded() {
+				hasEmbeds = true
+			}
+		}
+	}
+	if !hasEmbeds {
+		return
+	}
+	return t.FieldByNameFunc(func(s string) bool { return s == name })
+}
+
+// TypeOf returns the reflection Type that represents the dynamic type of i.
+// If i is a nil interface value, TypeOf returns nil.
+func TypeOf(i any) Type {
+	eface := *(*emptyInterface)(unsafe.Pointer(&i))
+	return toType(eface.typ)
+}
+
+// ptrMap is the cache for PointerTo.
+var ptrMap sync.Map // map[*rtype]*ptrType
+
+// PtrTo returns the pointer type with element t.
+// For example, if t represents type Foo, PtrTo(t) represents *Foo.
+//
+// PtrTo is the old spelling of PointerTo.
+// The two functions behave identically.
+func PtrTo(t Type) Type { return PointerTo(t) }
+
+// PointerTo returns the pointer type with element t.
+// For example, if t represents type Foo, PointerTo(t) represents *Foo.
+func PointerTo(t Type) Type {
+	return t.(*rtype).ptrTo()
+}
+
+func (t *rtype) ptrTo() *rtype {
+	if t.ptrToThis != 0 {
+		return t.typeOff(t.ptrToThis)
+	}
+
+	// Check the cache.
+	if pi, ok := ptrMap.Load(t); ok {
+		return &pi.(*ptrType).rtype
+	}
+
+	// Look in known types.
+	s := "*" + t.String()
+	for _, tt := range typesByString(s) {
+		p := (*ptrType)(unsafe.Pointer(tt))
+		if p.elem != t {
+			continue
+		}
+		pi, _ := ptrMap.LoadOrStore(t, p)
+		return &pi.(*ptrType).rtype
+	}
+
+	// Create a new ptrType starting with the description
+	// of an *unsafe.Pointer.
+	var iptr any = (*unsafe.Pointer)(nil)
+	prototype := *(**ptrType)(unsafe.Pointer(&iptr))
+	pp := *prototype
+
+	pp.str = resolveReflectName(newName(s, "", false, false))
+	pp.ptrToThis = 0
+
+	// For the type structures linked into the binary, the
+	// compiler provides a good hash of the string.
+	// Create a good hash for the new string by using
+	// the FNV-1 hash's mixing function to combine the
+	// old hash and the new "*".
+	pp.hash = fnv1(t.hash, '*')
+
+	pp.elem = t
+
+	pi, _ := ptrMap.LoadOrStore(t, &pp)
+	return &pi.(*ptrType).rtype
+}
+
+// fnv1 incorporates the list of bytes into the hash x using the FNV-1 hash function.
+func fnv1(x uint32, list ...byte) uint32 {
+	for _, b := range list {
+		x = x*16777619 ^ uint32(b)
+	}
+	return x
+}
+
+func (t *rtype) Implements(u Type) bool {
+	if u == nil {
+		panic("reflect: nil type passed to Type.Implements")
+	}
+	if u.Kind() != Interface {
+		panic("reflect: non-interface type passed to Type.Implements")
+	}
+	return implements(u.(*rtype), t)
+}
+
+func (t *rtype) AssignableTo(u Type) bool {
+	if u == nil {
+		panic("reflect: nil type passed to Type.AssignableTo")
+	}
+	uu := u.(*rtype)
+	return directlyAssignable(uu, t) || implements(uu, t)
+}
+
+func (t *rtype) ConvertibleTo(u Type) bool {
+	if u == nil {
+		panic("reflect: nil type passed to Type.ConvertibleTo")
+	}
+	uu := u.(*rtype)
+	return convertOp(uu, t) != nil
+}
+
+func (t *rtype) Comparable() bool {
+	return t.equal != nil
+}
+
+// implements reports whether the type V implements the interface type T.
+func implements(T, V *rtype) bool {
+	if T.Kind() != Interface {
+		return false
+	}
+	t := (*interfaceType)(unsafe.Pointer(T))
+	if len(t.methods) == 0 {
+		return true
+	}
+
+	// The same algorithm applies in both cases, but the
+	// method tables for an interface type and a concrete type
+	// are different, so the code is duplicated.
+	// In both cases the algorithm is a linear scan over the two
+	// lists - T's methods and V's methods - simultaneously.
+	// Since method tables are stored in a unique sorted order
+	// (alphabetical, with no duplicate method names), the scan
+	// through V's methods must hit a match for each of T's
+	// methods along the way, or else V does not implement T.
+	// This lets us run the scan in overall linear time instead of
+	// the quadratic time  a naive search would require.
+	// See also ../runtime/iface.go.
+	if V.Kind() == Interface {
+		v := (*interfaceType)(unsafe.Pointer(V))
+		i := 0
+		for j := 0; j < len(v.methods); j++ {
+			tm := &t.methods[i]
+			tmName := t.nameOff(tm.name)
+			vm := &v.methods[j]
+			vmName := V.nameOff(vm.name)
+			if vmName.name() == tmName.name() && V.typeOff(vm.typ) == t.typeOff(tm.typ) {
+				if !tmName.isExported() {
+					tmPkgPath := tmName.pkgPath()
+					if tmPkgPath == "" {
+						tmPkgPath = t.pkgPath.name()
+					}
+					vmPkgPath := vmName.pkgPath()
+					if vmPkgPath == "" {
+						vmPkgPath = v.pkgPath.name()
+					}
+					if tmPkgPath != vmPkgPath {
+						continue
+					}
+				}
+				if i++; i >= len(t.methods) {
+					return true
+				}
+			}
+		}
+		return false
+	}
+
+	v := V.uncommon()
+	if v == nil {
+		return false
+	}
+	i := 0
+	vmethods := v.methods()
+	for j := 0; j < int(v.mcount); j++ {
+		tm := &t.methods[i]
+		tmName := t.nameOff(tm.name)
+		vm := vmethods[j]
+		vmName := V.nameOff(vm.name)
+		if vmName.name() == tmName.name() && V.typeOff(vm.mtyp) == t.typeOff(tm.typ) {
+			if !tmName.isExported() {
+				tmPkgPath := tmName.pkgPath()
+				if tmPkgPath == "" {
+					tmPkgPath = t.pkgPath.name()
+				}
+				vmPkgPath := vmName.pkgPath()
+				if vmPkgPath == "" {
+					vmPkgPath = V.nameOff(v.pkgPath).name()
+				}
+				if tmPkgPath != vmPkgPath {
+					continue
+				}
+			}
+			if i++; i >= len(t.methods) {
+				return true
+			}
+		}
+	}
+	return false
+}
+
+// specialChannelAssignability reports whether a value x of channel type V
+// can be directly assigned (using memmove) to another channel type T.
+// https://golang.org/doc/go_spec.html#Assignability
+// T and V must be both of Chan kind.
+func specialChannelAssignability(T, V *rtype) bool {
+	// Special case:
+	// x is a bidirectional channel value, T is a channel type,
+	// x's type V and T have identical element types,
+	// and at least one of V or T is not a defined type.
+	return V.ChanDir() == BothDir && (T.Name() == "" || V.Name() == "") && haveIdenticalType(T.Elem(), V.Elem(), true)
+}
+
+// directlyAssignable reports whether a value x of type V can be directly
+// assigned (using memmove) to a value of type T.
+// https://golang.org/doc/go_spec.html#Assignability
+// Ignoring the interface rules (implemented elsewhere)
+// and the ideal constant rules (no ideal constants at run time).
+func directlyAssignable(T, V *rtype) bool {
+	// x's type V is identical to T?
+	if T == V {
+		return true
+	}
+
+	// Otherwise at least one of T and V must not be defined
+	// and they must have the same kind.
+	if T.hasName() && V.hasName() || T.Kind() != V.Kind() {
+		return false
+	}
+
+	if T.Kind() == Chan && specialChannelAssignability(T, V) {
+		return true
+	}
+
+	// x's type T and V must have identical underlying types.
+	return haveIdenticalUnderlyingType(T, V, true)
+}
+
+func haveIdenticalType(T, V Type, cmpTags bool) bool {
+	if cmpTags {
+		return T == V
+	}
+
+	if T.Name() != V.Name() || T.Kind() != V.Kind() || T.PkgPath() != V.PkgPath() {
+		return false
+	}
+
+	return haveIdenticalUnderlyingType(T.common(), V.common(), false)
+}
+
+func haveIdenticalUnderlyingType(T, V *rtype, cmpTags bool) bool {
+	if T == V {
+		return true
+	}
+
+	kind := T.Kind()
+	if kind != V.Kind() {
+		return false
+	}
+
+	// Non-composite types of equal kind have same underlying type
+	// (the predefined instance of the type).
+	if Bool <= kind && kind <= Complex128 || kind == String || kind == UnsafePointer {
+		return true
+	}
+
+	// Composite types.
+	switch kind {
+	case Array:
+		return T.Len() == V.Len() && haveIdenticalType(T.Elem(), V.Elem(), cmpTags)
+
+	case Chan:
+		return V.ChanDir() == T.ChanDir() && haveIdenticalType(T.Elem(), V.Elem(), cmpTags)
+
+	case Func:
+		t := (*funcType)(unsafe.Pointer(T))
+		v := (*funcType)(unsafe.Pointer(V))
+		if t.outCount != v.outCount || t.inCount != v.inCount {
+			return false
+		}
+		for i := 0; i < t.NumIn(); i++ {
+			if !haveIdenticalType(t.In(i), v.In(i), cmpTags) {
+				return false
+			}
+		}
+		for i := 0; i < t.NumOut(); i++ {
+			if !haveIdenticalType(t.Out(i), v.Out(i), cmpTags) {
+				return false
+			}
+		}
+		return true
+
+	case Interface:
+		t := (*interfaceType)(unsafe.Pointer(T))
+		v := (*interfaceType)(unsafe.Pointer(V))
+		if len(t.methods) == 0 && len(v.methods) == 0 {
+			return true
+		}
+		// Might have the same methods but still
+		// need a run time conversion.
+		return false
+
+	case Map:
+		return haveIdenticalType(T.Key(), V.Key(), cmpTags) && haveIdenticalType(T.Elem(), V.Elem(), cmpTags)
+
+	case Pointer, Slice:
+		return haveIdenticalType(T.Elem(), V.Elem(), cmpTags)
+
+	case Struct:
+		t := (*structType)(unsafe.Pointer(T))
+		v := (*structType)(unsafe.Pointer(V))
+		if len(t.fields) != len(v.fields) {
+			return false
+		}
+		if t.pkgPath.name() != v.pkgPath.name() {
+			return false
+		}
+		for i := range t.fields {
+			tf := &t.fields[i]
+			vf := &v.fields[i]
+			if tf.name.name() != vf.name.name() {
+				return false
+			}
+			if !haveIdenticalType(tf.typ, vf.typ, cmpTags) {
+				return false
+			}
+			if cmpTags && tf.name.tag() != vf.name.tag() {
+				return false
+			}
+			if tf.offset != vf.offset {
+				return false
+			}
+			if tf.embedded() != vf.embedded() {
+				return false
+			}
+		}
+		return true
+	}
+
+	return false
+}
+
+// typelinks is implemented in package runtime.
+// It returns a slice of the sections in each module,
+// and a slice of *rtype offsets in each module.
+//
+// The types in each module are sorted by string. That is, the first
+// two linked types of the first module are:
+//
+//	d0 := sections[0]
+//	t1 := (*rtype)(add(d0, offset[0][0]))
+//	t2 := (*rtype)(add(d0, offset[0][1]))
+//
+// and
+//
+//	t1.String() < t2.String()
+//
+// Note that strings are not unique identifiers for types:
+// there can be more than one with a given string.
+// Only types we might want to look up are included:
+// pointers, channels, maps, slices, and arrays.
+func typelinks() (sections []unsafe.Pointer, offset [][]int32)
+
+func rtypeOff(section unsafe.Pointer, off int32) *rtype {
+	return (*rtype)(add(section, uintptr(off), "sizeof(rtype) > 0"))
+}
+
+// typesByString returns the subslice of typelinks() whose elements have
+// the given string representation.
+// It may be empty (no known types with that string) or may have
+// multiple elements (multiple types with that string).
+func typesByString(s string) []*rtype {
+	sections, offset := typelinks()
+	var ret []*rtype
+
+	for offsI, offs := range offset {
+		section := sections[offsI]
+
+		// We are looking for the first index i where the string becomes >= s.
+		// This is a copy of sort.Search, with f(h) replaced by (*typ[h].String() >= s).
+		i, j := 0, len(offs)
+		for i < j {
+			h := i + (j-i)>>1 // avoid overflow when computing h
+			// i ≤ h < j
+			if !(rtypeOff(section, offs[h]).String() >= s) {
+				i = h + 1 // preserves f(i-1) == false
+			} else {
+				j = h // preserves f(j) == true
+			}
+		}
+		// i == j, f(i-1) == false, and f(j) (= f(i)) == true  =>  answer is i.
+
+		// Having found the first, linear scan forward to find the last.
+		// We could do a second binary search, but the caller is going
+		// to do a linear scan anyway.
+		for j := i; j < len(offs); j++ {
+			typ := rtypeOff(section, offs[j])
+			if typ.String() != s {
+				break
+			}
+			ret = append(ret, typ)
+		}
+	}
+	return ret
+}
+
+// The lookupCache caches ArrayOf, ChanOf, MapOf and SliceOf lookups.
+var lookupCache sync.Map // map[cacheKey]*rtype
+
+// A cacheKey is the key for use in the lookupCache.
+// Four values describe any of the types we are looking for:
+// type kind, one or two subtypes, and an extra integer.
+type cacheKey struct {
+	kind  Kind
+	t1    *rtype
+	t2    *rtype
+	extra uintptr
+}
+
+// The funcLookupCache caches FuncOf lookups.
+// FuncOf does not share the common lookupCache since cacheKey is not
+// sufficient to represent functions unambiguously.
+var funcLookupCache struct {
+	sync.Mutex // Guards stores (but not loads) on m.
+
+	// m is a map[uint32][]*rtype keyed by the hash calculated in FuncOf.
+	// Elements of m are append-only and thus safe for concurrent reading.
+	m sync.Map
+}
+
+// ChanOf returns the channel type with the given direction and element type.
+// For example, if t represents int, ChanOf(RecvDir, t) represents <-chan int.
+//
+// The gc runtime imposes a limit of 64 kB on channel element types.
+// If t's size is equal to or exceeds this limit, ChanOf panics.
+func ChanOf(dir ChanDir, t Type) Type {
+	typ := t.(*rtype)
+
+	// Look in cache.
+	ckey := cacheKey{Chan, typ, nil, uintptr(dir)}
+	if ch, ok := lookupCache.Load(ckey); ok {
+		return ch.(*rtype)
+	}
+
+	// This restriction is imposed by the gc compiler and the runtime.
+	if typ.size >= 1<<16 {
+		panic("reflect.ChanOf: element size too large")
+	}
+
+	// Look in known types.
+	var s string
+	switch dir {
+	default:
+		panic("reflect.ChanOf: invalid dir")
+	case SendDir:
+		s = "chan<- " + typ.String()
+	case RecvDir:
+		s = "<-chan " + typ.String()
+	case BothDir:
+		typeStr := typ.String()
+		if typeStr[0] == '<' {
+			// typ is recv chan, need parentheses as "<-" associates with leftmost
+			// chan possible, see:
+			// * https://golang.org/ref/spec#Channel_types
+			// * https://github.com/golang/go/issues/39897
+			s = "chan (" + typeStr + ")"
+		} else {
+			s = "chan " + typeStr
+		}
+	}
+	for _, tt := range typesByString(s) {
+		ch := (*chanType)(unsafe.Pointer(tt))
+		if ch.elem == typ && ch.dir == uintptr(dir) {
+			ti, _ := lookupCache.LoadOrStore(ckey, tt)
+			return ti.(Type)
+		}
+	}
+
+	// Make a channel type.
+	var ichan any = (chan unsafe.Pointer)(nil)
+	prototype := *(**chanType)(unsafe.Pointer(&ichan))
+	ch := *prototype
+	ch.tflag = tflagRegularMemory
+	ch.dir = uintptr(dir)
+	ch.str = resolveReflectName(newName(s, "", false, false))
+	ch.hash = fnv1(typ.hash, 'c', byte(dir))
+	ch.elem = typ
+
+	ti, _ := lookupCache.LoadOrStore(ckey, &ch.rtype)
+	return ti.(Type)
+}
+
+// MapOf returns the map type with the given key and element types.
+// For example, if k represents int and e represents string,
+// MapOf(k, e) represents map[int]string.
+//
+// If the key type is not a valid map key type (that is, if it does
+// not implement Go's == operator), MapOf panics.
+func MapOf(key, elem Type) Type {
+	ktyp := key.(*rtype)
+	etyp := elem.(*rtype)
+
+	if ktyp.equal == nil {
+		panic("reflect.MapOf: invalid key type " + ktyp.String())
+	}
+
+	// Look in cache.
+	ckey := cacheKey{Map, ktyp, etyp, 0}
+	if mt, ok := lookupCache.Load(ckey); ok {
+		return mt.(Type)
+	}
+
+	// Look in known types.
+	s := "map[" + ktyp.String() + "]" + etyp.String()
+	for _, tt := range typesByString(s) {
+		mt := (*mapType)(unsafe.Pointer(tt))
+		if mt.key == ktyp && mt.elem == etyp {
+			ti, _ := lookupCache.LoadOrStore(ckey, tt)
+			return ti.(Type)
+		}
+	}
+
+	// Make a map type.
+	// Note: flag values must match those used in the TMAP case
+	// in ../cmd/compile/internal/reflectdata/reflect.go:writeType.
+	var imap any = (map[unsafe.Pointer]unsafe.Pointer)(nil)
+	mt := **(**mapType)(unsafe.Pointer(&imap))
+	mt.str = resolveReflectName(newName(s, "", false, false))
+	mt.tflag = 0
+	mt.hash = fnv1(etyp.hash, 'm', byte(ktyp.hash>>24), byte(ktyp.hash>>16), byte(ktyp.hash>>8), byte(ktyp.hash))
+	mt.key = ktyp
+	mt.elem = etyp
+	mt.bucket = bucketOf(ktyp, etyp)
+	mt.hasher = func(p unsafe.Pointer, seed uintptr) uintptr {
+		return typehash(ktyp, p, seed)
+	}
+	mt.flags = 0
+	if ktyp.size > maxKeySize {
+		mt.keysize = uint8(goarch.PtrSize)
+		mt.flags |= 1 // indirect key
+	} else {
+		mt.keysize = uint8(ktyp.size)
+	}
+	if etyp.size > maxValSize {
+		mt.valuesize = uint8(goarch.PtrSize)
+		mt.flags |= 2 // indirect value
+	} else {
+		mt.valuesize = uint8(etyp.size)
+	}
+	mt.bucketsize = uint16(mt.bucket.size)
+	if isReflexive(ktyp) {
+		mt.flags |= 4
+	}
+	if needKeyUpdate(ktyp) {
+		mt.flags |= 8
+	}
+	if hashMightPanic(ktyp) {
+		mt.flags |= 16
+	}
+	mt.ptrToThis = 0
+
+	ti, _ := lookupCache.LoadOrStore(ckey, &mt.rtype)
+	return ti.(Type)
+}
+
+// TODO(crawshaw): as these funcTypeFixedN structs have no methods,
+// they could be defined at runtime using the StructOf function.
+type funcTypeFixed4 struct {
+	funcType
+	args [4]*rtype
+}
+type funcTypeFixed8 struct {
+	funcType
+	args [8]*rtype
+}
+type funcTypeFixed16 struct {
+	funcType
+	args [16]*rtype
+}
+type funcTypeFixed32 struct {
+	funcType
+	args [32]*rtype
+}
+type funcTypeFixed64 struct {
+	funcType
+	args [64]*rtype
+}
+type funcTypeFixed128 struct {
+	funcType
+	args [128]*rtype
+}
+
+// FuncOf returns the function type with the given argument and result types.
+// For example if k represents int and e represents string,
+// FuncOf([]Type{k}, []Type{e}, false) represents func(int) string.
+//
+// The variadic argument controls whether the function is variadic. FuncOf
+// panics if the in[len(in)-1] does not represent a slice and variadic is
+// true.
+func FuncOf(in, out []Type, variadic bool) Type {
+	if variadic && (len(in) == 0 || in[len(in)-1].Kind() != Slice) {
+		panic("reflect.FuncOf: last arg of variadic func must be slice")
+	}
+
+	// Make a func type.
+	var ifunc any = (func())(nil)
+	prototype := *(**funcType)(unsafe.Pointer(&ifunc))
+	n := len(in) + len(out)
+
+	var ft *funcType
+	var args []*rtype
+	switch {
+	case n <= 4:
+		fixed := new(funcTypeFixed4)
+		args = fixed.args[:0:len(fixed.args)]
+		ft = &fixed.funcType
+	case n <= 8:
+		fixed := new(funcTypeFixed8)
+		args = fixed.args[:0:len(fixed.args)]
+		ft = &fixed.funcType
+	case n <= 16:
+		fixed := new(funcTypeFixed16)
+		args = fixed.args[:0:len(fixed.args)]
+		ft = &fixed.funcType
+	case n <= 32:
+		fixed := new(funcTypeFixed32)
+		args = fixed.args[:0:len(fixed.args)]
+		ft = &fixed.funcType
+	case n <= 64:
+		fixed := new(funcTypeFixed64)
+		args = fixed.args[:0:len(fixed.args)]
+		ft = &fixed.funcType
+	case n <= 128:
+		fixed := new(funcTypeFixed128)
+		args = fixed.args[:0:len(fixed.args)]
+		ft = &fixed.funcType
+	default:
+		panic("reflect.FuncOf: too many arguments")
+	}
+	*ft = *prototype
+
+	// Build a hash and minimally populate ft.
+	var hash uint32
+	for _, in := range in {
+		t := in.(*rtype)
+		args = append(args, t)
+		hash = fnv1(hash, byte(t.hash>>24), byte(t.hash>>16), byte(t.hash>>8), byte(t.hash))
+	}
+	if variadic {
+		hash = fnv1(hash, 'v')
+	}
+	hash = fnv1(hash, '.')
+	for _, out := range out {
+		t := out.(*rtype)
+		args = append(args, t)
+		hash = fnv1(hash, byte(t.hash>>24), byte(t.hash>>16), byte(t.hash>>8), byte(t.hash))
+	}
+	if len(args) > 50 {
+		panic("reflect.FuncOf does not support more than 50 arguments")
+	}
+	ft.tflag = 0
+	ft.hash = hash
+	ft.inCount = uint16(len(in))
+	ft.outCount = uint16(len(out))
+	if variadic {
+		ft.outCount |= 1 << 15
+	}
+
+	// Look in cache.
+	if ts, ok := funcLookupCache.m.Load(hash); ok {
+		for _, t := range ts.([]*rtype) {
+			if haveIdenticalUnderlyingType(&ft.rtype, t, true) {
+				return t
+			}
+		}
+	}
+
+	// Not in cache, lock and retry.
+	funcLookupCache.Lock()
+	defer funcLookupCache.Unlock()
+	if ts, ok := funcLookupCache.m.Load(hash); ok {
+		for _, t := range ts.([]*rtype) {
+			if haveIdenticalUnderlyingType(&ft.rtype, t, true) {
+				return t
+			}
+		}
+	}
+
+	addToCache := func(tt *rtype) Type {
+		var rts []*rtype
+		if rti, ok := funcLookupCache.m.Load(hash); ok {
+			rts = rti.([]*rtype)
+		}
+		funcLookupCache.m.Store(hash, append(rts, tt))
+		return tt
+	}
+
+	// Look in known types for the same string representation.
+	str := funcStr(ft)
+	for _, tt := range typesByString(str) {
+		if haveIdenticalUnderlyingType(&ft.rtype, tt, true) {
+			return addToCache(tt)
+		}
+	}
+
+	// Populate the remaining fields of ft and store in cache.
+	ft.str = resolveReflectName(newName(str, "", false, false))
+	ft.ptrToThis = 0
+	return addToCache(&ft.rtype)
+}
+
+// funcStr builds a string representation of a funcType.
+func funcStr(ft *funcType) string {
+	repr := make([]byte, 0, 64)
+	repr = append(repr, "func("...)
+	for i, t := range ft.in() {
+		if i > 0 {
+			repr = append(repr, ", "...)
+		}
+		if ft.IsVariadic() && i == int(ft.inCount)-1 {
+			repr = append(repr, "..."...)
+			repr = append(repr, (*sliceType)(unsafe.Pointer(t)).elem.String()...)
+		} else {
+			repr = append(repr, t.String()...)
+		}
+	}
+	repr = append(repr, ')')
+	out := ft.out()
+	if len(out) == 1 {
+		repr = append(repr, ' ')
+	} else if len(out) > 1 {
+		repr = append(repr, " ("...)
+	}
+	for i, t := range out {
+		if i > 0 {
+			repr = append(repr, ", "...)
+		}
+		repr = append(repr, t.String()...)
+	}
+	if len(out) > 1 {
+		repr = append(repr, ')')
+	}
+	return string(repr)
+}
+
+// isReflexive reports whether the == operation on the type is reflexive.
+// That is, x == x for all values x of type t.
+func isReflexive(t *rtype) bool {
+	switch t.Kind() {
+	case Bool, Int, Int8, Int16, Int32, Int64, Uint, Uint8, Uint16, Uint32, Uint64, Uintptr, Chan, Pointer, String, UnsafePointer:
+		return true
+	case Float32, Float64, Complex64, Complex128, Interface:
+		return false
+	case Array:
+		tt := (*arrayType)(unsafe.Pointer(t))
+		return isReflexive(tt.elem)
+	case Struct:
+		tt := (*structType)(unsafe.Pointer(t))
+		for _, f := range tt.fields {
+			if !isReflexive(f.typ) {
+				return false
+			}
+		}
+		return true
+	default:
+		// Func, Map, Slice, Invalid
+		panic("isReflexive called on non-key type " + t.String())
+	}
+}
+
+// needKeyUpdate reports whether map overwrites require the key to be copied.
+func needKeyUpdate(t *rtype) bool {
+	switch t.Kind() {
+	case Bool, Int, Int8, Int16, Int32, Int64, Uint, Uint8, Uint16, Uint32, Uint64, Uintptr, Chan, Pointer, UnsafePointer:
+		return false
+	case Float32, Float64, Complex64, Complex128, Interface, String:
+		// Float keys can be updated from +0 to -0.
+		// String keys can be updated to use a smaller backing store.
+		// Interfaces might have floats of strings in them.
+		return true
+	case Array:
+		tt := (*arrayType)(unsafe.Pointer(t))
+		return needKeyUpdate(tt.elem)
+	case Struct:
+		tt := (*structType)(unsafe.Pointer(t))
+		for _, f := range tt.fields {
+			if needKeyUpdate(f.typ) {
+				return true
+			}
+		}
+		return false
+	default:
+		// Func, Map, Slice, Invalid
+		panic("needKeyUpdate called on non-key type " + t.String())
+	}
+}
+
+// hashMightPanic reports whether the hash of a map key of type t might panic.
+func hashMightPanic(t *rtype) bool {
+	switch t.Kind() {
+	case Interface:
+		return true
+	case Array:
+		tt := (*arrayType)(unsafe.Pointer(t))
+		return hashMightPanic(tt.elem)
+	case Struct:
+		tt := (*structType)(unsafe.Pointer(t))
+		for _, f := range tt.fields {
+			if hashMightPanic(f.typ) {
+				return true
+			}
+		}
+		return false
+	default:
+		return false
+	}
+}
+
+// Make sure these routines stay in sync with ../runtime/map.go!
+// These types exist only for GC, so we only fill out GC relevant info.
+// Currently, that's just size and the GC program. We also fill in string
+// for possible debugging use.
+const (
+	bucketSize uintptr = 8
+	maxKeySize uintptr = 128
+	maxValSize uintptr = 128
+)
+
+func bucketOf(ktyp, etyp *rtype) *rtype {
+	if ktyp.size > maxKeySize {
+		ktyp = PointerTo(ktyp).(*rtype)
+	}
+	if etyp.size > maxValSize {
+		etyp = PointerTo(etyp).(*rtype)
+	}
+
+	// Prepare GC data if any.
+	// A bucket is at most bucketSize*(1+maxKeySize+maxValSize)+ptrSize bytes,
+	// or 2064 bytes, or 258 pointer-size words, or 33 bytes of pointer bitmap.
+	// Note that since the key and value are known to be <= 128 bytes,
+	// they're guaranteed to have bitmaps instead of GC programs.
+	var gcdata *byte
+	var ptrdata uintptr
+
+	size := bucketSize*(1+ktyp.size+etyp.size) + goarch.PtrSize
+	if size&uintptr(ktyp.align-1) != 0 || size&uintptr(etyp.align-1) != 0 {
+		panic("reflect: bad size computation in MapOf")
+	}
+
+	if ktyp.ptrdata != 0 || etyp.ptrdata != 0 {
+		nptr := (bucketSize*(1+ktyp.size+etyp.size) + goarch.PtrSize) / goarch.PtrSize
+		mask := make([]byte, (nptr+7)/8)
+		base := bucketSize / goarch.PtrSize
+
+		if ktyp.ptrdata != 0 {
+			emitGCMask(mask, base, ktyp, bucketSize)
+		}
+		base += bucketSize * ktyp.size / goarch.PtrSize
+
+		if etyp.ptrdata != 0 {
+			emitGCMask(mask, base, etyp, bucketSize)
+		}
+		base += bucketSize * etyp.size / goarch.PtrSize
+
+		word := base
+		mask[word/8] |= 1 << (word % 8)
+		gcdata = &mask[0]
+		ptrdata = (word + 1) * goarch.PtrSize
+
+		// overflow word must be last
+		if ptrdata != size {
+			panic("reflect: bad layout computation in MapOf")
+		}
+	}
+
+	b := &rtype{
+		align:   goarch.PtrSize,
+		size:    size,
+		kind:    uint8(Struct),
+		ptrdata: ptrdata,
+		gcdata:  gcdata,
+	}
+	s := "bucket(" + ktyp.String() + "," + etyp.String() + ")"
+	b.str = resolveReflectName(newName(s, "", false, false))
+	return b
+}
+
+func (t *rtype) gcSlice(begin, end uintptr) []byte {
+	return (*[1 << 30]byte)(unsafe.Pointer(t.gcdata))[begin:end:end]
+}
+
+// emitGCMask writes the GC mask for [n]typ into out, starting at bit
+// offset base.
+func emitGCMask(out []byte, base uintptr, typ *rtype, n uintptr) {
+	if typ.kind&kindGCProg != 0 {
+		panic("reflect: unexpected GC program")
+	}
+	ptrs := typ.ptrdata / goarch.PtrSize
+	words := typ.size / goarch.PtrSize
+	mask := typ.gcSlice(0, (ptrs+7)/8)
+	for j := uintptr(0); j < ptrs; j++ {
+		if (mask[j/8]>>(j%8))&1 != 0 {
+			for i := uintptr(0); i < n; i++ {
+				k := base + i*words + j
+				out[k/8] |= 1 << (k % 8)
+			}
+		}
+	}
+}
+
+// appendGCProg appends the GC program for the first ptrdata bytes of
+// typ to dst and returns the extended slice.
+func appendGCProg(dst []byte, typ *rtype) []byte {
+	if typ.kind&kindGCProg != 0 {
+		// Element has GC program; emit one element.
+		n := uintptr(*(*uint32)(unsafe.Pointer(typ.gcdata)))
+		prog := typ.gcSlice(4, 4+n-1)
+		return append(dst, prog...)
+	}
+
+	// Element is small with pointer mask; use as literal bits.
+	ptrs := typ.ptrdata / goarch.PtrSize
+	mask := typ.gcSlice(0, (ptrs+7)/8)
+
+	// Emit 120-bit chunks of full bytes (max is 127 but we avoid using partial bytes).
+	for ; ptrs > 120; ptrs -= 120 {
+		dst = append(dst, 120)
+		dst = append(dst, mask[:15]...)
+		mask = mask[15:]
+	}
+
+	dst = append(dst, byte(ptrs))
+	dst = append(dst, mask...)
+	return dst
+}
+
+// SliceOf returns the slice type with element type t.
+// For example, if t represents int, SliceOf(t) represents []int.
+func SliceOf(t Type) Type {
+	typ := t.(*rtype)
+
+	// Look in cache.
+	ckey := cacheKey{Slice, typ, nil, 0}
+	if slice, ok := lookupCache.Load(ckey); ok {
+		return slice.(Type)
+	}
+
+	// Look in known types.
+	s := "[]" + typ.String()
+	for _, tt := range typesByString(s) {
+		slice := (*sliceType)(unsafe.Pointer(tt))
+		if slice.elem == typ {
+			ti, _ := lookupCache.LoadOrStore(ckey, tt)
+			return ti.(Type)
+		}
+	}
+
+	// Make a slice type.
+	var islice any = ([]unsafe.Pointer)(nil)
+	prototype := *(**sliceType)(unsafe.Pointer(&islice))
+	slice := *prototype
+	slice.tflag = 0
+	slice.str = resolveReflectName(newName(s, "", false, false))
+	slice.hash = fnv1(typ.hash, '[')
+	slice.elem = typ
+	slice.ptrToThis = 0
+
+	ti, _ := lookupCache.LoadOrStore(ckey, &slice.rtype)
+	return ti.(Type)
+}
+
+// The structLookupCache caches StructOf lookups.
+// StructOf does not share the common lookupCache since we need to pin
+// the memory associated with *structTypeFixedN.
+var structLookupCache struct {
+	sync.Mutex // Guards stores (but not loads) on m.
+
+	// m is a map[uint32][]Type keyed by the hash calculated in StructOf.
+	// Elements in m are append-only and thus safe for concurrent reading.
+	m sync.Map
+}
+
+type structTypeUncommon struct {
+	structType
+	u uncommonType
+}
+
+// isLetter reports whether a given 'rune' is classified as a Letter.
+func isLetter(ch rune) bool {
+	return 'a' <= ch && ch <= 'z' || 'A' <= ch && ch <= 'Z' || ch == '_' || ch >= utf8.RuneSelf && unicode.IsLetter(ch)
+}
+
+// isValidFieldName checks if a string is a valid (struct) field name or not.
+//
+// According to the language spec, a field name should be an identifier.
+//
+// identifier = letter { letter | unicode_digit } .
+// letter = unicode_letter | "_" .
+func isValidFieldName(fieldName string) bool {
+	for i, c := range fieldName {
+		if i == 0 && !isLetter(c) {
+			return false
+		}
+
+		if !(isLetter(c) || unicode.IsDigit(c)) {
+			return false
+		}
+	}
+
+	return len(fieldName) > 0
+}
+
+// StructOf returns the struct type containing fields.
+// The Offset and Index fields are ignored and computed as they would be
+// by the compiler.
+//
+// StructOf currently does not generate wrapper methods for embedded
+// fields and panics if passed unexported StructFields.
+// These limitations may be lifted in a future version.
+func StructOf(fields []StructField) Type {
+	var (
+		hash       = fnv1(0, []byte("struct {")...)
+		size       uintptr
+		typalign   uint8
+		comparable = true
+		methods    []method
+
+		fs   = make([]structField, len(fields))
+		repr = make([]byte, 0, 64)
+		fset = map[string]struct{}{} // fields' names
+
+		hasGCProg = false // records whether a struct-field type has a GCProg
+	)
+
+	lastzero := uintptr(0)
+	repr = append(repr, "struct {"...)
+	pkgpath := ""
+	for i, field := range fields {
+		if field.Name == "" {
+			panic("reflect.StructOf: field " + strconv.Itoa(i) + " has no name")
+		}
+		if !isValidFieldName(field.Name) {
+			panic("reflect.StructOf: field " + strconv.Itoa(i) + " has invalid name")
+		}
+		if field.Type == nil {
+			panic("reflect.StructOf: field " + strconv.Itoa(i) + " has no type")
+		}
+		f, fpkgpath := runtimeStructField(field)
+		ft := f.typ
+		if ft.kind&kindGCProg != 0 {
+			hasGCProg = true
+		}
+		if fpkgpath != "" {
+			if pkgpath == "" {
+				pkgpath = fpkgpath
+			} else if pkgpath != fpkgpath {
+				panic("reflect.Struct: fields with different PkgPath " + pkgpath + " and " + fpkgpath)
+			}
+		}
+
+		// Update string and hash
+		name := f.name.name()
+		hash = fnv1(hash, []byte(name)...)
+		repr = append(repr, (" " + name)...)
+		if f.embedded() {
+			// Embedded field
+			if f.typ.Kind() == Pointer {
+				// Embedded ** and *interface{} are illegal
+				elem := ft.Elem()
+				if k := elem.Kind(); k == Pointer || k == Interface {
+					panic("reflect.StructOf: illegal embedded field type " + ft.String())
+				}
+			}
+
+			switch f.typ.Kind() {
+			case Interface:
+				ift := (*interfaceType)(unsafe.Pointer(ft))
+				for im, m := range ift.methods {
+					if ift.nameOff(m.name).pkgPath() != "" {
+						// TODO(sbinet).  Issue 15924.
+						panic("reflect: embedded interface with unexported method(s) not implemented")
+					}
+
+					var (
+						mtyp    = ift.typeOff(m.typ)
+						ifield  = i
+						imethod = im
+						ifn     Value
+						tfn     Value
+					)
+
+					if ft.kind&kindDirectIface != 0 {
+						tfn = MakeFunc(mtyp, func(in []Value) []Value {
+							var args []Value
+							var recv = in[0]
+							if len(in) > 1 {
+								args = in[1:]
+							}
+							return recv.Field(ifield).Method(imethod).Call(args)
+						})
+						ifn = MakeFunc(mtyp, func(in []Value) []Value {
+							var args []Value
+							var recv = in[0]
+							if len(in) > 1 {
+								args = in[1:]
+							}
+							return recv.Field(ifield).Method(imethod).Call(args)
+						})
+					} else {
+						tfn = MakeFunc(mtyp, func(in []Value) []Value {
+							var args []Value
+							var recv = in[0]
+							if len(in) > 1 {
+								args = in[1:]
+							}
+							return recv.Field(ifield).Method(imethod).Call(args)
+						})
+						ifn = MakeFunc(mtyp, func(in []Value) []Value {
+							var args []Value
+							var recv = Indirect(in[0])
+							if len(in) > 1 {
+								args = in[1:]
+							}
+							return recv.Field(ifield).Method(imethod).Call(args)
+						})
+					}
+
+					methods = append(methods, method{
+						name: resolveReflectName(ift.nameOff(m.name)),
+						mtyp: resolveReflectType(mtyp),
+						ifn:  resolveReflectText(unsafe.Pointer(&ifn)),
+						tfn:  resolveReflectText(unsafe.Pointer(&tfn)),
+					})
+				}
+			case Pointer:
+				ptr := (*ptrType)(unsafe.Pointer(ft))
+				if unt := ptr.uncommon(); unt != nil {
+					if i > 0 && unt.mcount > 0 {
+						// Issue 15924.
+						panic("reflect: embedded type with methods not implemented if type is not first field")
+					}
+					if len(fields) > 1 {
+						panic("reflect: embedded type with methods not implemented if there is more than one field")
+					}
+					for _, m := range unt.methods() {
+						mname := ptr.nameOff(m.name)
+						if mname.pkgPath() != "" {
+							// TODO(sbinet).
+							// Issue 15924.
+							panic("reflect: embedded interface with unexported method(s) not implemented")
+						}
+						methods = append(methods, method{
+							name: resolveReflectName(mname),
+							mtyp: resolveReflectType(ptr.typeOff(m.mtyp)),
+							ifn:  resolveReflectText(ptr.textOff(m.ifn)),
+							tfn:  resolveReflectText(ptr.textOff(m.tfn)),
+						})
+					}
+				}
+				if unt := ptr.elem.uncommon(); unt != nil {
+					for _, m := range unt.methods() {
+						mname := ptr.nameOff(m.name)
+						if mname.pkgPath() != "" {
+							// TODO(sbinet)
+							// Issue 15924.
+							panic("reflect: embedded interface with unexported method(s) not implemented")
+						}
+						methods = append(methods, method{
+							name: resolveReflectName(mname),
+							mtyp: resolveReflectType(ptr.elem.typeOff(m.mtyp)),
+							ifn:  resolveReflectText(ptr.elem.textOff(m.ifn)),
+							tfn:  resolveReflectText(ptr.elem.textOff(m.tfn)),
+						})
+					}
+				}
+			default:
+				if unt := ft.uncommon(); unt != nil {
+					if i > 0 && unt.mcount > 0 {
+						// Issue 15924.
+						panic("reflect: embedded type with methods not implemented if type is not first field")
+					}
+					if len(fields) > 1 && ft.kind&kindDirectIface != 0 {
+						panic("reflect: embedded type with methods not implemented for non-pointer type")
+					}
+					for _, m := range unt.methods() {
+						mname := ft.nameOff(m.name)
+						if mname.pkgPath() != "" {
+							// TODO(sbinet)
+							// Issue 15924.
+							panic("reflect: embedded interface with unexported method(s) not implemented")
+						}
+						methods = append(methods, method{
+							name: resolveReflectName(mname),
+							mtyp: resolveReflectType(ft.typeOff(m.mtyp)),
+							ifn:  resolveReflectText(ft.textOff(m.ifn)),
+							tfn:  resolveReflectText(ft.textOff(m.tfn)),
+						})
+
+					}
+				}
+			}
+		}
+		if _, dup := fset[name]; dup && name != "_" {
+			panic("reflect.StructOf: duplicate field " + name)
+		}
+		fset[name] = struct{}{}
+
+		hash = fnv1(hash, byte(ft.hash>>24), byte(ft.hash>>16), byte(ft.hash>>8), byte(ft.hash))
+
+		repr = append(repr, (" " + ft.String())...)
+		if f.name.hasTag() {
+			hash = fnv1(hash, []byte(f.name.tag())...)
+			repr = append(repr, (" " + strconv.Quote(f.name.tag()))...)
+		}
+		if i < len(fields)-1 {
+			repr = append(repr, ';')
+		}
+
+		comparable = comparable && (ft.equal != nil)
+
+		offset := align(size, uintptr(ft.align))
+		if offset < size {
+			panic("reflect.StructOf: struct size would exceed virtual address space")
+		}
+		if ft.align > typalign {
+			typalign = ft.align
+		}
+		size = offset + ft.size
+		if size < offset {
+			panic("reflect.StructOf: struct size would exceed virtual address space")
+		}
+		f.offset = offset
+
+		if ft.size == 0 {
+			lastzero = size
+		}
+
+		fs[i] = f
+	}
+
+	if size > 0 && lastzero == size {
+		// This is a non-zero sized struct that ends in a
+		// zero-sized field. We add an extra byte of padding,
+		// to ensure that taking the address of the final
+		// zero-sized field can't manufacture a pointer to the
+		// next object in the heap. See issue 9401.
+		size++
+		if size == 0 {
+			panic("reflect.StructOf: struct size would exceed virtual address space")
+		}
+	}
+
+	var typ *structType
+	var ut *uncommonType
+
+	if len(methods) == 0 {
+		t := new(structTypeUncommon)
+		typ = &t.structType
+		ut = &t.u
+	} else {
+		// A *rtype representing a struct is followed directly in memory by an
+		// array of method objects representing the methods attached to the
+		// struct. To get the same layout for a run time generated type, we
+		// need an array directly following the uncommonType memory.
+		// A similar strategy is used for funcTypeFixed4, ...funcTypeFixedN.
+		tt := New(StructOf([]StructField{
+			{Name: "S", Type: TypeOf(structType{})},
+			{Name: "U", Type: TypeOf(uncommonType{})},
+			{Name: "M", Type: ArrayOf(len(methods), TypeOf(methods[0]))},
+		}))
+
+		typ = (*structType)(tt.Elem().Field(0).Addr().UnsafePointer())
+		ut = (*uncommonType)(tt.Elem().Field(1).Addr().UnsafePointer())
+
+		copy(tt.Elem().Field(2).Slice(0, len(methods)).Interface().([]method), methods)
+	}
+	// TODO(sbinet): Once we allow embedding multiple types,
+	// methods will need to be sorted like the compiler does.
+	// TODO(sbinet): Once we allow non-exported methods, we will
+	// need to compute xcount as the number of exported methods.
+	ut.mcount = uint16(len(methods))
+	ut.xcount = ut.mcount
+	ut.moff = uint32(unsafe.Sizeof(uncommonType{}))
+
+	if len(fs) > 0 {
+		repr = append(repr, ' ')
+	}
+	repr = append(repr, '}')
+	hash = fnv1(hash, '}')
+	str := string(repr)
+
+	// Round the size up to be a multiple of the alignment.
+	s := align(size, uintptr(typalign))
+	if s < size {
+		panic("reflect.StructOf: struct size would exceed virtual address space")
+	}
+	size = s
+
+	// Make the struct type.
+	var istruct any = struct{}{}
+	prototype := *(**structType)(unsafe.Pointer(&istruct))
+	*typ = *prototype
+	typ.fields = fs
+	if pkgpath != "" {
+		typ.pkgPath = newName(pkgpath, "", false, false)
+	}
+
+	// Look in cache.
+	if ts, ok := structLookupCache.m.Load(hash); ok {
+		for _, st := range ts.([]Type) {
+			t := st.common()
+			if haveIdenticalUnderlyingType(&typ.rtype, t, true) {
+				return t
+			}
+		}
+	}
+
+	// Not in cache, lock and retry.
+	structLookupCache.Lock()
+	defer structLookupCache.Unlock()
+	if ts, ok := structLookupCache.m.Load(hash); ok {
+		for _, st := range ts.([]Type) {
+			t := st.common()
+			if haveIdenticalUnderlyingType(&typ.rtype, t, true) {
+				return t
+			}
+		}
+	}
+
+	addToCache := func(t Type) Type {
+		var ts []Type
+		if ti, ok := structLookupCache.m.Load(hash); ok {
+			ts = ti.([]Type)
+		}
+		structLookupCache.m.Store(hash, append(ts, t))
+		return t
+	}
+
+	// Look in known types.
+	for _, t := range typesByString(str) {
+		if haveIdenticalUnderlyingType(&typ.rtype, t, true) {
+			// even if 't' wasn't a structType with methods, we should be ok
+			// as the 'u uncommonType' field won't be accessed except when
+			// tflag&tflagUncommon is set.
+			return addToCache(t)
+		}
+	}
+
+	typ.str = resolveReflectName(newName(str, "", false, false))
+	typ.tflag = 0 // TODO: set tflagRegularMemory
+	typ.hash = hash
+	typ.size = size
+	typ.ptrdata = typeptrdata(typ.common())
+	typ.align = typalign
+	typ.fieldAlign = typalign
+	typ.ptrToThis = 0
+	if len(methods) > 0 {
+		typ.tflag |= tflagUncommon
+	}
+
+	if hasGCProg {
+		lastPtrField := 0
+		for i, ft := range fs {
+			if ft.typ.pointers() {
+				lastPtrField = i
+			}
+		}
+		prog := []byte{0, 0, 0, 0} // will be length of prog
+		var off uintptr
+		for i, ft := range fs {
+			if i > lastPtrField {
+				// gcprog should not include anything for any field after
+				// the last field that contains pointer data
+				break
+			}
+			if !ft.typ.pointers() {
+				// Ignore pointerless fields.
+				continue
+			}
+			// Pad to start of this field with zeros.
+			if ft.offset > off {
+				n := (ft.offset - off) / goarch.PtrSize
+				prog = append(prog, 0x01, 0x00) // emit a 0 bit
+				if n > 1 {
+					prog = append(prog, 0x81)      // repeat previous bit
+					prog = appendVarint(prog, n-1) // n-1 times
+				}
+				off = ft.offset
+			}
+
+			prog = appendGCProg(prog, ft.typ)
+			off += ft.typ.ptrdata
+		}
+		prog = append(prog, 0)
+		*(*uint32)(unsafe.Pointer(&prog[0])) = uint32(len(prog) - 4)
+		typ.kind |= kindGCProg
+		typ.gcdata = &prog[0]
+	} else {
+		typ.kind &^= kindGCProg
+		bv := new(bitVector)
+		addTypeBits(bv, 0, typ.common())
+		if len(bv.data) > 0 {
+			typ.gcdata = &bv.data[0]
+		}
+	}
+	typ.equal = nil
+	if comparable {
+		typ.equal = func(p, q unsafe.Pointer) bool {
+			for _, ft := range typ.fields {
+				pi := add(p, ft.offset, "&x.field safe")
+				qi := add(q, ft.offset, "&x.field safe")
+				if !ft.typ.equal(pi, qi) {
+					return false
+				}
+			}
+			return true
+		}
+	}
+
+	switch {
+	case len(fs) == 1 && !ifaceIndir(fs[0].typ):
+		// structs of 1 direct iface type can be direct
+		typ.kind |= kindDirectIface
+	default:
+		typ.kind &^= kindDirectIface
+	}
+
+	return addToCache(&typ.rtype)
+}
+
+// runtimeStructField takes a StructField value passed to StructOf and
+// returns both the corresponding internal representation, of type
+// structField, and the pkgpath value to use for this field.
+func runtimeStructField(field StructField) (structField, string) {
+	if field.Anonymous && field.PkgPath != "" {
+		panic("reflect.StructOf: field \"" + field.Name + "\" is anonymous but has PkgPath set")
+	}
+
+	if field.IsExported() {
+		// Best-effort check for misuse.
+		// Since this field will be treated as exported, not much harm done if Unicode lowercase slips through.
+		c := field.Name[0]
+		if 'a' <= c && c <= 'z' || c == '_' {
+			panic("reflect.StructOf: field \"" + field.Name + "\" is unexported but missing PkgPath")
+		}
+	}
+
+	resolveReflectType(field.Type.common()) // install in runtime
+	f := structField{
+		name:   newName(field.Name, string(field.Tag), field.IsExported(), field.Anonymous),
+		typ:    field.Type.common(),
+		offset: 0,
+	}
+	return f, field.PkgPath
+}
+
+// typeptrdata returns the length in bytes of the prefix of t
+// containing pointer data. Anything after this offset is scalar data.
+// keep in sync with ../cmd/compile/internal/reflectdata/reflect.go
+func typeptrdata(t *rtype) uintptr {
+	switch t.Kind() {
+	case Struct:
+		st := (*structType)(unsafe.Pointer(t))
+		// find the last field that has pointers.
+		field := -1
+		for i := range st.fields {
+			ft := st.fields[i].typ
+			if ft.pointers() {
+				field = i
+			}
+		}
+		if field == -1 {
+			return 0
+		}
+		f := st.fields[field]
+		return f.offset + f.typ.ptrdata
+
+	default:
+		panic("reflect.typeptrdata: unexpected type, " + t.String())
+	}
+}
+
+// See cmd/compile/internal/reflectdata/reflect.go for derivation of constant.
+const maxPtrmaskBytes = 2048
+
+// ArrayOf returns the array type with the given length and element type.
+// For example, if t represents int, ArrayOf(5, t) represents [5]int.
+//
+// If the resulting type would be larger than the available address space,
+// ArrayOf panics.
+func ArrayOf(length int, elem Type) Type {
+	if length < 0 {
+		panic("reflect: negative length passed to ArrayOf")
+	}
+
+	typ := elem.(*rtype)
+
+	// Look in cache.
+	ckey := cacheKey{Array, typ, nil, uintptr(length)}
+	if array, ok := lookupCache.Load(ckey); ok {
+		return array.(Type)
+	}
+
+	// Look in known types.
+	s := "[" + strconv.Itoa(length) + "]" + typ.String()
+	for _, tt := range typesByString(s) {
+		array := (*arrayType)(unsafe.Pointer(tt))
+		if array.elem == typ {
+			ti, _ := lookupCache.LoadOrStore(ckey, tt)
+			return ti.(Type)
+		}
+	}
+
+	// Make an array type.
+	var iarray any = [1]unsafe.Pointer{}
+	prototype := *(**arrayType)(unsafe.Pointer(&iarray))
+	array := *prototype
+	array.tflag = typ.tflag & tflagRegularMemory
+	array.str = resolveReflectName(newName(s, "", false, false))
+	array.hash = fnv1(typ.hash, '[')
+	for n := uint32(length); n > 0; n >>= 8 {
+		array.hash = fnv1(array.hash, byte(n))
+	}
+	array.hash = fnv1(array.hash, ']')
+	array.elem = typ
+	array.ptrToThis = 0
+	if typ.size > 0 {
+		max := ^uintptr(0) / typ.size
+		if uintptr(length) > max {
+			panic("reflect.ArrayOf: array size would exceed virtual address space")
+		}
+	}
+	array.size = typ.size * uintptr(length)
+	if length > 0 && typ.ptrdata != 0 {
+		array.ptrdata = typ.size*uintptr(length-1) + typ.ptrdata
+	}
+	array.align = typ.align
+	array.fieldAlign = typ.fieldAlign
+	array.len = uintptr(length)
+	array.slice = SliceOf(elem).(*rtype)
+
+	switch {
+	case typ.ptrdata == 0 || array.size == 0:
+		// No pointers.
+		array.gcdata = nil
+		array.ptrdata = 0
+
+	case length == 1:
+		// In memory, 1-element array looks just like the element.
+		array.kind |= typ.kind & kindGCProg
+		array.gcdata = typ.gcdata
+		array.ptrdata = typ.ptrdata
+
+	case typ.kind&kindGCProg == 0 && array.size <= maxPtrmaskBytes*8*goarch.PtrSize:
+		// Element is small with pointer mask; array is still small.
+		// Create direct pointer mask by turning each 1 bit in elem
+		// into length 1 bits in larger mask.
+		mask := make([]byte, (array.ptrdata/goarch.PtrSize+7)/8)
+		emitGCMask(mask, 0, typ, array.len)
+		array.gcdata = &mask[0]
+
+	default:
+		// Create program that emits one element
+		// and then repeats to make the array.
+		prog := []byte{0, 0, 0, 0} // will be length of prog
+		prog = appendGCProg(prog, typ)
+		// Pad from ptrdata to size.
+		elemPtrs := typ.ptrdata / goarch.PtrSize
+		elemWords := typ.size / goarch.PtrSize
+		if elemPtrs < elemWords {
+			// Emit literal 0 bit, then repeat as needed.
+			prog = append(prog, 0x01, 0x00)
+			if elemPtrs+1 < elemWords {
+				prog = append(prog, 0x81)
+				prog = appendVarint(prog, elemWords-elemPtrs-1)
+			}
+		}
+		// Repeat length-1 times.
+		if elemWords < 0x80 {
+			prog = append(prog, byte(elemWords|0x80))
+		} else {
+			prog = append(prog, 0x80)
+			prog = appendVarint(prog, elemWords)
+		}
+		prog = appendVarint(prog, uintptr(length)-1)
+		prog = append(prog, 0)
+		*(*uint32)(unsafe.Pointer(&prog[0])) = uint32(len(prog) - 4)
+		array.kind |= kindGCProg
+		array.gcdata = &prog[0]
+		array.ptrdata = array.size // overestimate but ok; must match program
+	}
+
+	etyp := typ.common()
+	esize := etyp.Size()
+
+	array.equal = nil
+	if eequal := etyp.equal; eequal != nil {
+		array.equal = func(p, q unsafe.Pointer) bool {
+			for i := 0; i < length; i++ {
+				pi := arrayAt(p, i, esize, "i < length")
+				qi := arrayAt(q, i, esize, "i < length")
+				if !eequal(pi, qi) {
+					return false
+				}
+
+			}
+			return true
+		}
+	}
+
+	switch {
+	case length == 1 && !ifaceIndir(typ):
+		// array of 1 direct iface type can be direct
+		array.kind |= kindDirectIface
+	default:
+		array.kind &^= kindDirectIface
+	}
+
+	ti, _ := lookupCache.LoadOrStore(ckey, &array.rtype)
+	return ti.(Type)
+}
+
+func appendVarint(x []byte, v uintptr) []byte {
+	for ; v >= 0x80; v >>= 7 {
+		x = append(x, byte(v|0x80))
+	}
+	x = append(x, byte(v))
+	return x
+}
+
+// toType converts from a *rtype to a Type that can be returned
+// to the client of package reflect. In gc, the only concern is that
+// a nil *rtype must be replaced by a nil Type, but in gccgo this
+// function takes care of ensuring that multiple *rtype for the same
+// type are coalesced into a single Type.
+func toType(t *rtype) Type {
+	if t == nil {
+		return nil
+	}
+	return t
+}
+
+type layoutKey struct {
+	ftyp *funcType // function signature
+	rcvr *rtype    // receiver type, or nil if none
+}
+
+type layoutType struct {
+	t         *rtype
+	framePool *sync.Pool
+	abid      abiDesc
+}
+
+var layoutCache sync.Map // map[layoutKey]layoutType
+
+// funcLayout computes a struct type representing the layout of the
+// stack-assigned function arguments and return values for the function
+// type t.
+// If rcvr != nil, rcvr specifies the type of the receiver.
+// The returned type exists only for GC, so we only fill out GC relevant info.
+// Currently, that's just size and the GC program. We also fill in
+// the name for possible debugging use.
+func funcLayout(t *funcType, rcvr *rtype) (frametype *rtype, framePool *sync.Pool, abid abiDesc) {
+	if t.Kind() != Func {
+		panic("reflect: funcLayout of non-func type " + t.String())
+	}
+	if rcvr != nil && rcvr.Kind() == Interface {
+		panic("reflect: funcLayout with interface receiver " + rcvr.String())
+	}
+	k := layoutKey{t, rcvr}
+	if lti, ok := layoutCache.Load(k); ok {
+		lt := lti.(layoutType)
+		return lt.t, lt.framePool, lt.abid
+	}
+
+	// Compute the ABI layout.
+	abid = newAbiDesc(t, rcvr)
+
+	// build dummy rtype holding gc program
+	x := &rtype{
+		align: goarch.PtrSize,
+		// Don't add spill space here; it's only necessary in
+		// reflectcall's frame, not in the allocated frame.
+		// TODO(mknyszek): Remove this comment when register
+		// spill space in the frame is no longer required.
+		size:    align(abid.retOffset+abid.ret.stackBytes, goarch.PtrSize),
+		ptrdata: uintptr(abid.stackPtrs.n) * goarch.PtrSize,
+	}
+	if abid.stackPtrs.n > 0 {
+		x.gcdata = &abid.stackPtrs.data[0]
+	}
+
+	var s string
+	if rcvr != nil {
+		s = "methodargs(" + rcvr.String() + ")(" + t.String() + ")"
+	} else {
+		s = "funcargs(" + t.String() + ")"
+	}
+	x.str = resolveReflectName(newName(s, "", false, false))
+
+	// cache result for future callers
+	framePool = &sync.Pool{New: func() any {
+		return unsafe_New(x)
+	}}
+	lti, _ := layoutCache.LoadOrStore(k, layoutType{
+		t:         x,
+		framePool: framePool,
+		abid:      abid,
+	})
+	lt := lti.(layoutType)
+	return lt.t, lt.framePool, lt.abid
+}
+
+// ifaceIndir reports whether t is stored indirectly in an interface value.
+func ifaceIndir(t *rtype) bool {
+	return t.kind&kindDirectIface == 0
+}
+
+// Note: this type must agree with runtime.bitvector.
+type bitVector struct {
+	n    uint32 // number of bits
+	data []byte
+}
+
+// append a bit to the bitmap.
+func (bv *bitVector) append(bit uint8) {
+	if bv.n%8 == 0 {
+		bv.data = append(bv.data, 0)
+	}
+	bv.data[bv.n/8] |= bit << (bv.n % 8)
+	bv.n++
+}
+
+func addTypeBits(bv *bitVector, offset uintptr, t *rtype) {
+	if t.ptrdata == 0 {
+		return
+	}
+
+	switch Kind(t.kind & kindMask) {
+	case Chan, Func, Map, Pointer, Slice, String, UnsafePointer:
+		// 1 pointer at start of representation
+		for bv.n < uint32(offset/uintptr(goarch.PtrSize)) {
+			bv.append(0)
+		}
+		bv.append(1)
+
+	case Interface:
+		// 2 pointers
+		for bv.n < uint32(offset/uintptr(goarch.PtrSize)) {
+			bv.append(0)
+		}
+		bv.append(1)
+		bv.append(1)
+
+	case Array:
+		// repeat inner type
+		tt := (*arrayType)(unsafe.Pointer(t))
+		for i := 0; i < int(tt.len); i++ {
+			addTypeBits(bv, offset+uintptr(i)*tt.elem.size, tt.elem)
+		}
+
+	case Struct:
+		// apply fields
+		tt := (*structType)(unsafe.Pointer(t))
+		for i := range tt.fields {
+			f := &tt.fields[i]
+			addTypeBits(bv, offset+f.offset, f.typ)
+		}
+	}
+}
diff --git a/contrib/go/_std_1.19/src/reflect/value.go b/contrib/go/_std_1.19/src/reflect/value.go
new file mode 100644
index 0000000000..74554a3ac8
--- /dev/null
+++ b/contrib/go/_std_1.19/src/reflect/value.go
@@ -0,0 +1,3620 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package reflect
+
+import (
+	"errors"
+	"internal/abi"
+	"internal/goarch"
+	"internal/itoa"
+	"internal/unsafeheader"
+	"math"
+	"runtime"
+	"unsafe"
+)
+
+// Value is the reflection interface to a Go value.
+//
+// Not all methods apply to all kinds of values. Restrictions,
+// if any, are noted in the documentation for each method.
+// Use the Kind method to find out the kind of value before
+// calling kind-specific methods. Calling a method
+// inappropriate to the kind of type causes a run time panic.
+//
+// The zero Value represents no value.
+// Its IsValid method returns false, its Kind method returns Invalid,
+// its String method returns "<invalid Value>", and all other methods panic.
+// Most functions and methods never return an invalid value.
+// If one does, its documentation states the conditions explicitly.
+//
+// A Value can be used concurrently by multiple goroutines provided that
+// the underlying Go value can be used concurrently for the equivalent
+// direct operations.
+//
+// To compare two Values, compare the results of the Interface method.
+// Using == on two Values does not compare the underlying values
+// they represent.
+type Value struct {
+	// typ holds the type of the value represented by a Value.
+	typ *rtype
+
+	// Pointer-valued data or, if flagIndir is set, pointer to data.
+	// Valid when either flagIndir is set or typ.pointers() is true.
+	ptr unsafe.Pointer
+
+	// flag holds metadata about the value.
+	// The lowest bits are flag bits:
+	//	- flagStickyRO: obtained via unexported not embedded field, so read-only
+	//	- flagEmbedRO: obtained via unexported embedded field, so read-only
+	//	- flagIndir: val holds a pointer to the data
+	//	- flagAddr: v.CanAddr is true (implies flagIndir)
+	//	- flagMethod: v is a method value.
+	// The next five bits give the Kind of the value.
+	// This repeats typ.Kind() except for method values.
+	// The remaining 23+ bits give a method number for method values.
+	// If flag.kind() != Func, code can assume that flagMethod is unset.
+	// If ifaceIndir(typ), code can assume that flagIndir is set.
+	flag
+
+	// A method value represents a curried method invocation
+	// like r.Read for some receiver r. The typ+val+flag bits describe
+	// the receiver r, but the flag's Kind bits say Func (methods are
+	// functions), and the top bits of the flag give the method number
+	// in r's type's method table.
+}
+
+type flag uintptr
+
+const (
+	flagKindWidth        = 5 // there are 27 kinds
+	flagKindMask    flag = 1<<flagKindWidth - 1
+	flagStickyRO    flag = 1 << 5
+	flagEmbedRO     flag = 1 << 6
+	flagIndir       flag = 1 << 7
+	flagAddr        flag = 1 << 8
+	flagMethod      flag = 1 << 9
+	flagMethodShift      = 10
+	flagRO          flag = flagStickyRO | flagEmbedRO
+)
+
+func (f flag) kind() Kind {
+	return Kind(f & flagKindMask)
+}
+
+func (f flag) ro() flag {
+	if f&flagRO != 0 {
+		return flagStickyRO
+	}
+	return 0
+}
+
+// pointer returns the underlying pointer represented by v.
+// v.Kind() must be Pointer, Map, Chan, Func, or UnsafePointer
+// if v.Kind() == Pointer, the base type must not be go:notinheap.
+func (v Value) pointer() unsafe.Pointer {
+	if v.typ.size != goarch.PtrSize || !v.typ.pointers() {
+		panic("can't call pointer on a non-pointer Value")
+	}
+	if v.flag&flagIndir != 0 {
+		return *(*unsafe.Pointer)(v.ptr)
+	}
+	return v.ptr
+}
+
+// packEface converts v to the empty interface.
+func packEface(v Value) any {
+	t := v.typ
+	var i any
+	e := (*emptyInterface)(unsafe.Pointer(&i))
+	// First, fill in the data portion of the interface.
+	switch {
+	case ifaceIndir(t):
+		if v.flag&flagIndir == 0 {
+			panic("bad indir")
+		}
+		// Value is indirect, and so is the interface we're making.
+		ptr := v.ptr
+		if v.flag&flagAddr != 0 {
+			// TODO: pass safe boolean from valueInterface so
+			// we don't need to copy if safe==true?
+			c := unsafe_New(t)
+			typedmemmove(t, c, ptr)
+			ptr = c
+		}
+		e.word = ptr
+	case v.flag&flagIndir != 0:
+		// Value is indirect, but interface is direct. We need
+		// to load the data at v.ptr into the interface data word.
+		e.word = *(*unsafe.Pointer)(v.ptr)
+	default:
+		// Value is direct, and so is the interface.
+		e.word = v.ptr
+	}
+	// Now, fill in the type portion. We're very careful here not
+	// to have any operation between the e.word and e.typ assignments
+	// that would let the garbage collector observe the partially-built
+	// interface value.
+	e.typ = t
+	return i
+}
+
+// unpackEface converts the empty interface i to a Value.
+func unpackEface(i any) Value {
+	e := (*emptyInterface)(unsafe.Pointer(&i))
+	// NOTE: don't read e.word until we know whether it is really a pointer or not.
+	t := e.typ
+	if t == nil {
+		return Value{}
+	}
+	f := flag(t.Kind())
+	if ifaceIndir(t) {
+		f |= flagIndir
+	}
+	return Value{t, e.word, f}
+}
+
+// A ValueError occurs when a Value method is invoked on
+// a Value that does not support it. Such cases are documented
+// in the description of each method.
+type ValueError struct {
+	Method string
+	Kind   Kind
+}
+
+func (e *ValueError) Error() string {
+	if e.Kind == 0 {
+		return "reflect: call of " + e.Method + " on zero Value"
+	}
+	return "reflect: call of " + e.Method + " on " + e.Kind.String() + " Value"
+}
+
+// valueMethodName returns the name of the exported calling method on Value.
+func valueMethodName() string {
+	var pc [5]uintptr
+	n := runtime.Callers(1, pc[:])
+	frames := runtime.CallersFrames(pc[:n])
+	var frame runtime.Frame
+	for more := true; more; {
+		const prefix = "reflect.Value."
+		frame, more = frames.Next()
+		name := frame.Function
+		if len(name) > len(prefix) && name[:len(prefix)] == prefix {
+			methodName := name[len(prefix):]
+			if len(methodName) > 0 && 'A' <= methodName[0] && methodName[0] <= 'Z' {
+				return name
+			}
+		}
+	}
+	return "unknown method"
+}
+
+// emptyInterface is the header for an interface{} value.
+type emptyInterface struct {
+	typ  *rtype
+	word unsafe.Pointer
+}
+
+// nonEmptyInterface is the header for an interface value with methods.
+type nonEmptyInterface struct {
+	// see ../runtime/iface.go:/Itab
+	itab *struct {
+		ityp *rtype // static interface type
+		typ  *rtype // dynamic concrete type
+		hash uint32 // copy of typ.hash
+		_    [4]byte
+		fun  [100000]unsafe.Pointer // method table
+	}
+	word unsafe.Pointer
+}
+
+// mustBe panics if f's kind is not expected.
+// Making this a method on flag instead of on Value
+// (and embedding flag in Value) means that we can write
+// the very clear v.mustBe(Bool) and have it compile into
+// v.flag.mustBe(Bool), which will only bother to copy the
+// single important word for the receiver.
+func (f flag) mustBe(expected Kind) {
+	// TODO(mvdan): use f.kind() again once mid-stack inlining gets better
+	if Kind(f&flagKindMask) != expected {
+		panic(&ValueError{valueMethodName(), f.kind()})
+	}
+}
+
+// mustBeExported panics if f records that the value was obtained using
+// an unexported field.
+func (f flag) mustBeExported() {
+	if f == 0 || f&flagRO != 0 {
+		f.mustBeExportedSlow()
+	}
+}
+
+func (f flag) mustBeExportedSlow() {
+	if f == 0 {
+		panic(&ValueError{valueMethodName(), Invalid})
+	}
+	if f&flagRO != 0 {
+		panic("reflect: " + valueMethodName() + " using value obtained using unexported field")
+	}
+}
+
+// mustBeAssignable panics if f records that the value is not assignable,
+// which is to say that either it was obtained using an unexported field
+// or it is not addressable.
+func (f flag) mustBeAssignable() {
+	if f&flagRO != 0 || f&flagAddr == 0 {
+		f.mustBeAssignableSlow()
+	}
+}
+
+func (f flag) mustBeAssignableSlow() {
+	if f == 0 {
+		panic(&ValueError{valueMethodName(), Invalid})
+	}
+	// Assignable if addressable and not read-only.
+	if f&flagRO != 0 {
+		panic("reflect: " + valueMethodName() + " using value obtained using unexported field")
+	}
+	if f&flagAddr == 0 {
+		panic("reflect: " + valueMethodName() + " using unaddressable value")
+	}
+}
+
+// Addr returns a pointer value representing the address of v.
+// It panics if CanAddr() returns false.
+// Addr is typically used to obtain a pointer to a struct field
+// or slice element in order to call a method that requires a
+// pointer receiver.
+func (v Value) Addr() Value {
+	if v.flag&flagAddr == 0 {
+		panic("reflect.Value.Addr of unaddressable value")
+	}
+	// Preserve flagRO instead of using v.flag.ro() so that
+	// v.Addr().Elem() is equivalent to v (#32772)
+	fl := v.flag & flagRO
+	return Value{v.typ.ptrTo(), v.ptr, fl | flag(Pointer)}
+}
+
+// Bool returns v's underlying value.
+// It panics if v's kind is not Bool.
+func (v Value) Bool() bool {
+	// panicNotBool is split out to keep Bool inlineable.
+	if v.kind() != Bool {
+		v.panicNotBool()
+	}
+	return *(*bool)(v.ptr)
+}
+
+func (v Value) panicNotBool() {
+	v.mustBe(Bool)
+}
+
+var bytesType = TypeOf(([]byte)(nil)).(*rtype)
+
+// Bytes returns v's underlying value.
+// It panics if v's underlying value is not a slice of bytes or
+// an addressable array of bytes.
+func (v Value) Bytes() []byte {
+	// bytesSlow is split out to keep Bytes inlineable for unnamed []byte.
+	if v.typ == bytesType {
+		return *(*[]byte)(v.ptr)
+	}
+	return v.bytesSlow()
+}
+
+func (v Value) bytesSlow() []byte {
+	switch v.kind() {
+	case Slice:
+		if v.typ.Elem().Kind() != Uint8 {
+			panic("reflect.Value.Bytes of non-byte slice")
+		}
+		// Slice is always bigger than a word; assume flagIndir.
+		return *(*[]byte)(v.ptr)
+	case Array:
+		if v.typ.Elem().Kind() != Uint8 {
+			panic("reflect.Value.Bytes of non-byte array")
+		}
+		if !v.CanAddr() {
+			panic("reflect.Value.Bytes of unaddressable byte array")
+		}
+		p := (*byte)(v.ptr)
+		n := int((*arrayType)(unsafe.Pointer(v.typ)).len)
+		return unsafe.Slice(p, n)
+	}
+	panic(&ValueError{"reflect.Value.Bytes", v.kind()})
+}
+
+// runes returns v's underlying value.
+// It panics if v's underlying value is not a slice of runes (int32s).
+func (v Value) runes() []rune {
+	v.mustBe(Slice)
+	if v.typ.Elem().Kind() != Int32 {
+		panic("reflect.Value.Bytes of non-rune slice")
+	}
+	// Slice is always bigger than a word; assume flagIndir.
+	return *(*[]rune)(v.ptr)
+}
+
+// CanAddr reports whether the value's address can be obtained with Addr.
+// Such values are called addressable. A value is addressable if it is
+// an element of a slice, an element of an addressable array,
+// a field of an addressable struct, or the result of dereferencing a pointer.
+// If CanAddr returns false, calling Addr will panic.
+func (v Value) CanAddr() bool {
+	return v.flag&flagAddr != 0
+}
+
+// CanSet reports whether the value of v can be changed.
+// A Value can be changed only if it is addressable and was not
+// obtained by the use of unexported struct fields.
+// If CanSet returns false, calling Set or any type-specific
+// setter (e.g., SetBool, SetInt) will panic.
+func (v Value) CanSet() bool {
+	return v.flag&(flagAddr|flagRO) == flagAddr
+}
+
+// Call calls the function v with the input arguments in.
+// For example, if len(in) == 3, v.Call(in) represents the Go call v(in[0], in[1], in[2]).
+// Call panics if v's Kind is not Func.
+// It returns the output results as Values.
+// As in Go, each input argument must be assignable to the
+// type of the function's corresponding input parameter.
+// If v is a variadic function, Call creates the variadic slice parameter
+// itself, copying in the corresponding values.
+func (v Value) Call(in []Value) []Value {
+	v.mustBe(Func)
+	v.mustBeExported()
+	return v.call("Call", in)
+}
+
+// CallSlice calls the variadic function v with the input arguments in,
+// assigning the slice in[len(in)-1] to v's final variadic argument.
+// For example, if len(in) == 3, v.CallSlice(in) represents the Go call v(in[0], in[1], in[2]...).
+// CallSlice panics if v's Kind is not Func or if v is not variadic.
+// It returns the output results as Values.
+// As in Go, each input argument must be assignable to the
+// type of the function's corresponding input parameter.
+func (v Value) CallSlice(in []Value) []Value {
+	v.mustBe(Func)
+	v.mustBeExported()
+	return v.call("CallSlice", in)
+}
+
+var callGC bool // for testing; see TestCallMethodJump and TestCallArgLive
+
+const debugReflectCall = false
+
+func (v Value) call(op string, in []Value) []Value {
+	// Get function pointer, type.
+	t := (*funcType)(unsafe.Pointer(v.typ))
+	var (
+		fn       unsafe.Pointer
+		rcvr     Value
+		rcvrtype *rtype
+	)
+	if v.flag&flagMethod != 0 {
+		rcvr = v
+		rcvrtype, t, fn = methodReceiver(op, v, int(v.flag)>>flagMethodShift)
+	} else if v.flag&flagIndir != 0 {
+		fn = *(*unsafe.Pointer)(v.ptr)
+	} else {
+		fn = v.ptr
+	}
+
+	if fn == nil {
+		panic("reflect.Value.Call: call of nil function")
+	}
+
+	isSlice := op == "CallSlice"
+	n := t.NumIn()
+	isVariadic := t.IsVariadic()
+	if isSlice {
+		if !isVariadic {
+			panic("reflect: CallSlice of non-variadic function")
+		}
+		if len(in) < n {
+			panic("reflect: CallSlice with too few input arguments")
+		}
+		if len(in) > n {
+			panic("reflect: CallSlice with too many input arguments")
+		}
+	} else {
+		if isVariadic {
+			n--
+		}
+		if len(in) < n {
+			panic("reflect: Call with too few input arguments")
+		}
+		if !isVariadic && len(in) > n {
+			panic("reflect: Call with too many input arguments")
+		}
+	}
+	for _, x := range in {
+		if x.Kind() == Invalid {
+			panic("reflect: " + op + " using zero Value argument")
+		}
+	}
+	for i := 0; i < n; i++ {
+		if xt, targ := in[i].Type(), t.In(i); !xt.AssignableTo(targ) {
+			panic("reflect: " + op + " using " + xt.String() + " as type " + targ.String())
+		}
+	}
+	if !isSlice && isVariadic {
+		// prepare slice for remaining values
+		m := len(in) - n
+		slice := MakeSlice(t.In(n), m, m)
+		elem := t.In(n).Elem()
+		for i := 0; i < m; i++ {
+			x := in[n+i]
+			if xt := x.Type(); !xt.AssignableTo(elem) {
+				panic("reflect: cannot use " + xt.String() + " as type " + elem.String() + " in " + op)
+			}
+			slice.Index(i).Set(x)
+		}
+		origIn := in
+		in = make([]Value, n+1)
+		copy(in[:n], origIn)
+		in[n] = slice
+	}
+
+	nin := len(in)
+	if nin != t.NumIn() {
+		panic("reflect.Value.Call: wrong argument count")
+	}
+	nout := t.NumOut()
+
+	// Register argument space.
+	var regArgs abi.RegArgs
+
+	// Compute frame type.
+	frametype, framePool, abid := funcLayout(t, rcvrtype)
+
+	// Allocate a chunk of memory for frame if needed.
+	var stackArgs unsafe.Pointer
+	if frametype.size != 0 {
+		if nout == 0 {
+			stackArgs = framePool.Get().(unsafe.Pointer)
+		} else {
+			// Can't use pool if the function has return values.
+			// We will leak pointer to args in ret, so its lifetime is not scoped.
+			stackArgs = unsafe_New(frametype)
+		}
+	}
+	frameSize := frametype.size
+
+	if debugReflectCall {
+		println("reflect.call", t.String())
+		abid.dump()
+	}
+
+	// Copy inputs into args.
+
+	// Handle receiver.
+	inStart := 0
+	if rcvrtype != nil {
+		// Guaranteed to only be one word in size,
+		// so it will only take up exactly 1 abiStep (either
+		// in a register or on the stack).
+		switch st := abid.call.steps[0]; st.kind {
+		case abiStepStack:
+			storeRcvr(rcvr, stackArgs)
+		case abiStepPointer:
+			storeRcvr(rcvr, unsafe.Pointer(&regArgs.Ptrs[st.ireg]))
+			fallthrough
+		case abiStepIntReg:
+			storeRcvr(rcvr, unsafe.Pointer(&regArgs.Ints[st.ireg]))
+		case abiStepFloatReg:
+			storeRcvr(rcvr, unsafe.Pointer(&regArgs.Floats[st.freg]))
+		default:
+			panic("unknown ABI parameter kind")
+		}
+		inStart = 1
+	}
+
+	// Handle arguments.
+	for i, v := range in {
+		v.mustBeExported()
+		targ := t.In(i).(*rtype)
+		// TODO(mknyszek): Figure out if it's possible to get some
+		// scratch space for this assignment check. Previously, it
+		// was possible to use space in the argument frame.
+		v = v.assignTo("reflect.Value.Call", targ, nil)
+	stepsLoop:
+		for _, st := range abid.call.stepsForValue(i + inStart) {
+			switch st.kind {
+			case abiStepStack:
+				// Copy values to the "stack."
+				addr := add(stackArgs, st.stkOff, "precomputed stack arg offset")
+				if v.flag&flagIndir != 0 {
+					typedmemmove(targ, addr, v.ptr)
+				} else {
+					*(*unsafe.Pointer)(addr) = v.ptr
+				}
+				// There's only one step for a stack-allocated value.
+				break stepsLoop
+			case abiStepIntReg, abiStepPointer:
+				// Copy values to "integer registers."
+				if v.flag&flagIndir != 0 {
+					offset := add(v.ptr, st.offset, "precomputed value offset")
+					if st.kind == abiStepPointer {
+						// Duplicate this pointer in the pointer area of the
+						// register space. Otherwise, there's the potential for
+						// this to be the last reference to v.ptr.
+						regArgs.Ptrs[st.ireg] = *(*unsafe.Pointer)(offset)
+					}
+					intToReg(&regArgs, st.ireg, st.size, offset)
+				} else {
+					if st.kind == abiStepPointer {
+						// See the comment in abiStepPointer case above.
+						regArgs.Ptrs[st.ireg] = v.ptr
+					}
+					regArgs.Ints[st.ireg] = uintptr(v.ptr)
+				}
+			case abiStepFloatReg:
+				// Copy values to "float registers."
+				if v.flag&flagIndir == 0 {
+					panic("attempted to copy pointer to FP register")
+				}
+				offset := add(v.ptr, st.offset, "precomputed value offset")
+				floatToReg(&regArgs, st.freg, st.size, offset)
+			default:
+				panic("unknown ABI part kind")
+			}
+		}
+	}
+	// TODO(mknyszek): Remove this when we no longer have
+	// caller reserved spill space.
+	frameSize = align(frameSize, goarch.PtrSize)
+	frameSize += abid.spill
+
+	// Mark pointers in registers for the return path.
+	regArgs.ReturnIsPtr = abid.outRegPtrs
+
+	if debugReflectCall {
+		regArgs.Dump()
+	}
+
+	// For testing; see TestCallArgLive.
+	if callGC {
+		runtime.GC()
+	}
+
+	// Call.
+	call(frametype, fn, stackArgs, uint32(frametype.size), uint32(abid.retOffset), uint32(frameSize), &regArgs)
+
+	// For testing; see TestCallMethodJump.
+	if callGC {
+		runtime.GC()
+	}
+
+	var ret []Value
+	if nout == 0 {
+		if stackArgs != nil {
+			typedmemclr(frametype, stackArgs)
+			framePool.Put(stackArgs)
+		}
+	} else {
+		if stackArgs != nil {
+			// Zero the now unused input area of args,
+			// because the Values returned by this function contain pointers to the args object,
+			// and will thus keep the args object alive indefinitely.
+			typedmemclrpartial(frametype, stackArgs, 0, abid.retOffset)
+		}
+
+		// Wrap Values around return values in args.
+		ret = make([]Value, nout)
+		for i := 0; i < nout; i++ {
+			tv := t.Out(i)
+			if tv.Size() == 0 {
+				// For zero-sized return value, args+off may point to the next object.
+				// In this case, return the zero value instead.
+				ret[i] = Zero(tv)
+				continue
+			}
+			steps := abid.ret.stepsForValue(i)
+			if st := steps[0]; st.kind == abiStepStack {
+				// This value is on the stack. If part of a value is stack
+				// allocated, the entire value is according to the ABI. So
+				// just make an indirection into the allocated frame.
+				fl := flagIndir | flag(tv.Kind())
+				ret[i] = Value{tv.common(), add(stackArgs, st.stkOff, "tv.Size() != 0"), fl}
+				// Note: this does introduce false sharing between results -
+				// if any result is live, they are all live.
+				// (And the space for the args is live as well, but as we've
+				// cleared that space it isn't as big a deal.)
+				continue
+			}
+
+			// Handle pointers passed in registers.
+			if !ifaceIndir(tv.common()) {
+				// Pointer-valued data gets put directly
+				// into v.ptr.
+				if steps[0].kind != abiStepPointer {
+					print("kind=", steps[0].kind, ", type=", tv.String(), "\n")
+					panic("mismatch between ABI description and types")
+				}
+				ret[i] = Value{tv.common(), regArgs.Ptrs[steps[0].ireg], flag(tv.Kind())}
+				continue
+			}
+
+			// All that's left is values passed in registers that we need to
+			// create space for and copy values back into.
+			//
+			// TODO(mknyszek): We make a new allocation for each register-allocated
+			// value, but previously we could always point into the heap-allocated
+			// stack frame. This is a regression that could be fixed by adding
+			// additional space to the allocated stack frame and storing the
+			// register-allocated return values into the allocated stack frame and
+			// referring there in the resulting Value.
+			s := unsafe_New(tv.common())
+			for _, st := range steps {
+				switch st.kind {
+				case abiStepIntReg:
+					offset := add(s, st.offset, "precomputed value offset")
+					intFromReg(&regArgs, st.ireg, st.size, offset)
+				case abiStepPointer:
+					s := add(s, st.offset, "precomputed value offset")
+					*((*unsafe.Pointer)(s)) = regArgs.Ptrs[st.ireg]
+				case abiStepFloatReg:
+					offset := add(s, st.offset, "precomputed value offset")
+					floatFromReg(&regArgs, st.freg, st.size, offset)
+				case abiStepStack:
+					panic("register-based return value has stack component")
+				default:
+					panic("unknown ABI part kind")
+				}
+			}
+			ret[i] = Value{tv.common(), s, flagIndir | flag(tv.Kind())}
+		}
+	}
+
+	return ret
+}
+
+// callReflect is the call implementation used by a function
+// returned by MakeFunc. In many ways it is the opposite of the
+// method Value.call above. The method above converts a call using Values
+// into a call of a function with a concrete argument frame, while
+// callReflect converts a call of a function with a concrete argument
+// frame into a call using Values.
+// It is in this file so that it can be next to the call method above.
+// The remainder of the MakeFunc implementation is in makefunc.go.
+//
+// NOTE: This function must be marked as a "wrapper" in the generated code,
+// so that the linker can make it work correctly for panic and recover.
+// The gc compilers know to do that for the name "reflect.callReflect".
+//
+// ctxt is the "closure" generated by MakeFunc.
+// frame is a pointer to the arguments to that closure on the stack.
+// retValid points to a boolean which should be set when the results
+// section of frame is set.
+//
+// regs contains the argument values passed in registers and will contain
+// the values returned from ctxt.fn in registers.
+func callReflect(ctxt *makeFuncImpl, frame unsafe.Pointer, retValid *bool, regs *abi.RegArgs) {
+	if callGC {
+		// Call GC upon entry during testing.
+		// Getting our stack scanned here is the biggest hazard, because
+		// our caller (makeFuncStub) could have failed to place the last
+		// pointer to a value in regs' pointer space, in which case it
+		// won't be visible to the GC.
+		runtime.GC()
+	}
+	ftyp := ctxt.ftyp
+	f := ctxt.fn
+
+	_, _, abid := funcLayout(ftyp, nil)
+
+	// Copy arguments into Values.
+	ptr := frame
+	in := make([]Value, 0, int(ftyp.inCount))
+	for i, typ := range ftyp.in() {
+		if typ.Size() == 0 {
+			in = append(in, Zero(typ))
+			continue
+		}
+		v := Value{typ, nil, flag(typ.Kind())}
+		steps := abid.call.stepsForValue(i)
+		if st := steps[0]; st.kind == abiStepStack {
+			if ifaceIndir(typ) {
+				// value cannot be inlined in interface data.
+				// Must make a copy, because f might keep a reference to it,
+				// and we cannot let f keep a reference to the stack frame
+				// after this function returns, not even a read-only reference.
+				v.ptr = unsafe_New(typ)
+				if typ.size > 0 {
+					typedmemmove(typ, v.ptr, add(ptr, st.stkOff, "typ.size > 0"))
+				}
+				v.flag |= flagIndir
+			} else {
+				v.ptr = *(*unsafe.Pointer)(add(ptr, st.stkOff, "1-ptr"))
+			}
+		} else {
+			if ifaceIndir(typ) {
+				// All that's left is values passed in registers that we need to
+				// create space for the values.
+				v.flag |= flagIndir
+				v.ptr = unsafe_New(typ)
+				for _, st := range steps {
+					switch st.kind {
+					case abiStepIntReg:
+						offset := add(v.ptr, st.offset, "precomputed value offset")
+						intFromReg(regs, st.ireg, st.size, offset)
+					case abiStepPointer:
+						s := add(v.ptr, st.offset, "precomputed value offset")
+						*((*unsafe.Pointer)(s)) = regs.Ptrs[st.ireg]
+					case abiStepFloatReg:
+						offset := add(v.ptr, st.offset, "precomputed value offset")
+						floatFromReg(regs, st.freg, st.size, offset)
+					case abiStepStack:
+						panic("register-based return value has stack component")
+					default:
+						panic("unknown ABI part kind")
+					}
+				}
+			} else {
+				// Pointer-valued data gets put directly
+				// into v.ptr.
+				if steps[0].kind != abiStepPointer {
+					print("kind=", steps[0].kind, ", type=", typ.String(), "\n")
+					panic("mismatch between ABI description and types")
+				}
+				v.ptr = regs.Ptrs[steps[0].ireg]
+			}
+		}
+		in = append(in, v)
+	}
+
+	// Call underlying function.
+	out := f(in)
+	numOut := ftyp.NumOut()
+	if len(out) != numOut {
+		panic("reflect: wrong return count from function created by MakeFunc")
+	}
+
+	// Copy results back into argument frame and register space.
+	if numOut > 0 {
+		for i, typ := range ftyp.out() {
+			v := out[i]
+			if v.typ == nil {
+				panic("reflect: function created by MakeFunc using " + funcName(f) +
+					" returned zero Value")
+			}
+			if v.flag&flagRO != 0 {
+				panic("reflect: function created by MakeFunc using " + funcName(f) +
+					" returned value obtained from unexported field")
+			}
+			if typ.size == 0 {
+				continue
+			}
+
+			// Convert v to type typ if v is assignable to a variable
+			// of type t in the language spec.
+			// See issue 28761.
+			//
+			//
+			// TODO(mknyszek): In the switch to the register ABI we lost
+			// the scratch space here for the register cases (and
+			// temporarily for all the cases).
+			//
+			// If/when this happens, take note of the following:
+			//
+			// We must clear the destination before calling assignTo,
+			// in case assignTo writes (with memory barriers) to the
+			// target location used as scratch space. See issue 39541.
+			v = v.assignTo("reflect.MakeFunc", typ, nil)
+		stepsLoop:
+			for _, st := range abid.ret.stepsForValue(i) {
+				switch st.kind {
+				case abiStepStack:
+					// Copy values to the "stack."
+					addr := add(ptr, st.stkOff, "precomputed stack arg offset")
+					// Do not use write barriers. The stack space used
+					// for this call is not adequately zeroed, and we
+					// are careful to keep the arguments alive until we
+					// return to makeFuncStub's caller.
+					if v.flag&flagIndir != 0 {
+						memmove(addr, v.ptr, st.size)
+					} else {
+						// This case must be a pointer type.
+						*(*uintptr)(addr) = uintptr(v.ptr)
+					}
+					// There's only one step for a stack-allocated value.
+					break stepsLoop
+				case abiStepIntReg, abiStepPointer:
+					// Copy values to "integer registers."
+					if v.flag&flagIndir != 0 {
+						offset := add(v.ptr, st.offset, "precomputed value offset")
+						intToReg(regs, st.ireg, st.size, offset)
+					} else {
+						// Only populate the Ints space on the return path.
+						// This is safe because out is kept alive until the
+						// end of this function, and the return path through
+						// makeFuncStub has no preemption, so these pointers
+						// are always visible to the GC.
+						regs.Ints[st.ireg] = uintptr(v.ptr)
+					}
+				case abiStepFloatReg:
+					// Copy values to "float registers."
+					if v.flag&flagIndir == 0 {
+						panic("attempted to copy pointer to FP register")
+					}
+					offset := add(v.ptr, st.offset, "precomputed value offset")
+					floatToReg(regs, st.freg, st.size, offset)
+				default:
+					panic("unknown ABI part kind")
+				}
+			}
+		}
+	}
+
+	// Announce that the return values are valid.
+	// After this point the runtime can depend on the return values being valid.
+	*retValid = true
+
+	// We have to make sure that the out slice lives at least until
+	// the runtime knows the return values are valid. Otherwise, the
+	// return values might not be scanned by anyone during a GC.
+	// (out would be dead, and the return slots not yet alive.)
+	runtime.KeepAlive(out)
+
+	// runtime.getArgInfo expects to be able to find ctxt on the
+	// stack when it finds our caller, makeFuncStub. Make sure it
+	// doesn't get garbage collected.
+	runtime.KeepAlive(ctxt)
+}
+
+// methodReceiver returns information about the receiver
+// described by v. The Value v may or may not have the
+// flagMethod bit set, so the kind cached in v.flag should
+// not be used.
+// The return value rcvrtype gives the method's actual receiver type.
+// The return value t gives the method type signature (without the receiver).
+// The return value fn is a pointer to the method code.
+func methodReceiver(op string, v Value, methodIndex int) (rcvrtype *rtype, t *funcType, fn unsafe.Pointer) {
+	i := methodIndex
+	if v.typ.Kind() == Interface {
+		tt := (*interfaceType)(unsafe.Pointer(v.typ))
+		if uint(i) >= uint(len(tt.methods)) {
+			panic("reflect: internal error: invalid method index")
+		}
+		m := &tt.methods[i]
+		if !tt.nameOff(m.name).isExported() {
+			panic("reflect: " + op + " of unexported method")
+		}
+		iface := (*nonEmptyInterface)(v.ptr)
+		if iface.itab == nil {
+			panic("reflect: " + op + " of method on nil interface value")
+		}
+		rcvrtype = iface.itab.typ
+		fn = unsafe.Pointer(&iface.itab.fun[i])
+		t = (*funcType)(unsafe.Pointer(tt.typeOff(m.typ)))
+	} else {
+		rcvrtype = v.typ
+		ms := v.typ.exportedMethods()
+		if uint(i) >= uint(len(ms)) {
+			panic("reflect: internal error: invalid method index")
+		}
+		m := ms[i]
+		if !v.typ.nameOff(m.name).isExported() {
+			panic("reflect: " + op + " of unexported method")
+		}
+		ifn := v.typ.textOff(m.ifn)
+		fn = unsafe.Pointer(&ifn)
+		t = (*funcType)(unsafe.Pointer(v.typ.typeOff(m.mtyp)))
+	}
+	return
+}
+
+// v is a method receiver. Store at p the word which is used to
+// encode that receiver at the start of the argument list.
+// Reflect uses the "interface" calling convention for
+// methods, which always uses one word to record the receiver.
+func storeRcvr(v Value, p unsafe.Pointer) {
+	t := v.typ
+	if t.Kind() == Interface {
+		// the interface data word becomes the receiver word
+		iface := (*nonEmptyInterface)(v.ptr)
+		*(*unsafe.Pointer)(p) = iface.word
+	} else if v.flag&flagIndir != 0 && !ifaceIndir(t) {
+		*(*unsafe.Pointer)(p) = *(*unsafe.Pointer)(v.ptr)
+	} else {
+		*(*unsafe.Pointer)(p) = v.ptr
+	}
+}
+
+// align returns the result of rounding x up to a multiple of n.
+// n must be a power of two.
+func align(x, n uintptr) uintptr {
+	return (x + n - 1) &^ (n - 1)
+}
+
+// callMethod is the call implementation used by a function returned
+// by makeMethodValue (used by v.Method(i).Interface()).
+// It is a streamlined version of the usual reflect call: the caller has
+// already laid out the argument frame for us, so we don't have
+// to deal with individual Values for each argument.
+// It is in this file so that it can be next to the two similar functions above.
+// The remainder of the makeMethodValue implementation is in makefunc.go.
+//
+// NOTE: This function must be marked as a "wrapper" in the generated code,
+// so that the linker can make it work correctly for panic and recover.
+// The gc compilers know to do that for the name "reflect.callMethod".
+//
+// ctxt is the "closure" generated by makeVethodValue.
+// frame is a pointer to the arguments to that closure on the stack.
+// retValid points to a boolean which should be set when the results
+// section of frame is set.
+//
+// regs contains the argument values passed in registers and will contain
+// the values returned from ctxt.fn in registers.
+func callMethod(ctxt *methodValue, frame unsafe.Pointer, retValid *bool, regs *abi.RegArgs) {
+	rcvr := ctxt.rcvr
+	rcvrType, valueFuncType, methodFn := methodReceiver("call", rcvr, ctxt.method)
+
+	// There are two ABIs at play here.
+	//
+	// methodValueCall was invoked with the ABI assuming there was no
+	// receiver ("value ABI") and that's what frame and regs are holding.
+	//
+	// Meanwhile, we need to actually call the method with a receiver, which
+	// has its own ABI ("method ABI"). Everything that follows is a translation
+	// between the two.
+	_, _, valueABI := funcLayout(valueFuncType, nil)
+	valueFrame, valueRegs := frame, regs
+	methodFrameType, methodFramePool, methodABI := funcLayout(valueFuncType, rcvrType)
+
+	// Make a new frame that is one word bigger so we can store the receiver.
+	// This space is used for both arguments and return values.
+	methodFrame := methodFramePool.Get().(unsafe.Pointer)
+	var methodRegs abi.RegArgs
+
+	// Deal with the receiver. It's guaranteed to only be one word in size.
+	switch st := methodABI.call.steps[0]; st.kind {
+	case abiStepStack:
+		// Only copy the receiver to the stack if the ABI says so.
+		// Otherwise, it'll be in a register already.
+		storeRcvr(rcvr, methodFrame)
+	case abiStepPointer:
+		// Put the receiver in a register.
+		storeRcvr(rcvr, unsafe.Pointer(&methodRegs.Ptrs[st.ireg]))
+		fallthrough
+	case abiStepIntReg:
+		storeRcvr(rcvr, unsafe.Pointer(&methodRegs.Ints[st.ireg]))
+	case abiStepFloatReg:
+		storeRcvr(rcvr, unsafe.Pointer(&methodRegs.Floats[st.freg]))
+	default:
+		panic("unknown ABI parameter kind")
+	}
+
+	// Translate the rest of the arguments.
+	for i, t := range valueFuncType.in() {
+		valueSteps := valueABI.call.stepsForValue(i)
+		methodSteps := methodABI.call.stepsForValue(i + 1)
+
+		// Zero-sized types are trivial: nothing to do.
+		if len(valueSteps) == 0 {
+			if len(methodSteps) != 0 {
+				panic("method ABI and value ABI do not align")
+			}
+			continue
+		}
+
+		// There are four cases to handle in translating each
+		// argument:
+		// 1. Stack -> stack translation.
+		// 2. Stack -> registers translation.
+		// 3. Registers -> stack translation.
+		// 4. Registers -> registers translation.
+
+		// If the value ABI passes the value on the stack,
+		// then the method ABI does too, because it has strictly
+		// fewer arguments. Simply copy between the two.
+		if vStep := valueSteps[0]; vStep.kind == abiStepStack {
+			mStep := methodSteps[0]
+			// Handle stack -> stack translation.
+			if mStep.kind == abiStepStack {
+				if vStep.size != mStep.size {
+					panic("method ABI and value ABI do not align")
+				}
+				typedmemmove(t,
+					add(methodFrame, mStep.stkOff, "precomputed stack offset"),
+					add(valueFrame, vStep.stkOff, "precomputed stack offset"))
+				continue
+			}
+			// Handle stack -> register translation.
+			for _, mStep := range methodSteps {
+				from := add(valueFrame, vStep.stkOff+mStep.offset, "precomputed stack offset")
+				switch mStep.kind {
+				case abiStepPointer:
+					// Do the pointer copy directly so we get a write barrier.
+					methodRegs.Ptrs[mStep.ireg] = *(*unsafe.Pointer)(from)
+					fallthrough // We need to make sure this ends up in Ints, too.
+				case abiStepIntReg:
+					intToReg(&methodRegs, mStep.ireg, mStep.size, from)
+				case abiStepFloatReg:
+					floatToReg(&methodRegs, mStep.freg, mStep.size, from)
+				default:
+					panic("unexpected method step")
+				}
+			}
+			continue
+		}
+		// Handle register -> stack translation.
+		if mStep := methodSteps[0]; mStep.kind == abiStepStack {
+			for _, vStep := range valueSteps {
+				to := add(methodFrame, mStep.stkOff+vStep.offset, "precomputed stack offset")
+				switch vStep.kind {
+				case abiStepPointer:
+					// Do the pointer copy directly so we get a write barrier.
+					*(*unsafe.Pointer)(to) = valueRegs.Ptrs[vStep.ireg]
+				case abiStepIntReg:
+					intFromReg(valueRegs, vStep.ireg, vStep.size, to)
+				case abiStepFloatReg:
+					floatFromReg(valueRegs, vStep.freg, vStep.size, to)
+				default:
+					panic("unexpected value step")
+				}
+			}
+			continue
+		}
+		// Handle register -> register translation.
+		if len(valueSteps) != len(methodSteps) {
+			// Because it's the same type for the value, and it's assigned
+			// to registers both times, it should always take up the same
+			// number of registers for each ABI.
+			panic("method ABI and value ABI don't align")
+		}
+		for i, vStep := range valueSteps {
+			mStep := methodSteps[i]
+			if mStep.kind != vStep.kind {
+				panic("method ABI and value ABI don't align")
+			}
+			switch vStep.kind {
+			case abiStepPointer:
+				// Copy this too, so we get a write barrier.
+				methodRegs.Ptrs[mStep.ireg] = valueRegs.Ptrs[vStep.ireg]
+				fallthrough
+			case abiStepIntReg:
+				methodRegs.Ints[mStep.ireg] = valueRegs.Ints[vStep.ireg]
+			case abiStepFloatReg:
+				methodRegs.Floats[mStep.freg] = valueRegs.Floats[vStep.freg]
+			default:
+				panic("unexpected value step")
+			}
+		}
+	}
+
+	methodFrameSize := methodFrameType.size
+	// TODO(mknyszek): Remove this when we no longer have
+	// caller reserved spill space.
+	methodFrameSize = align(methodFrameSize, goarch.PtrSize)
+	methodFrameSize += methodABI.spill
+
+	// Mark pointers in registers for the return path.
+	methodRegs.ReturnIsPtr = methodABI.outRegPtrs
+
+	// Call.
+	// Call copies the arguments from scratch to the stack, calls fn,
+	// and then copies the results back into scratch.
+	call(methodFrameType, methodFn, methodFrame, uint32(methodFrameType.size), uint32(methodABI.retOffset), uint32(methodFrameSize), &methodRegs)
+
+	// Copy return values.
+	//
+	// This is somewhat simpler because both ABIs have an identical
+	// return value ABI (the types are identical). As a result, register
+	// results can simply be copied over. Stack-allocated values are laid
+	// out the same, but are at different offsets from the start of the frame
+	// Ignore any changes to args.
+	// Avoid constructing out-of-bounds pointers if there are no return values.
+	// because the arguments may be laid out differently.
+	if valueRegs != nil {
+		*valueRegs = methodRegs
+	}
+	if retSize := methodFrameType.size - methodABI.retOffset; retSize > 0 {
+		valueRet := add(valueFrame, valueABI.retOffset, "valueFrame's size > retOffset")
+		methodRet := add(methodFrame, methodABI.retOffset, "methodFrame's size > retOffset")
+		// This copies to the stack. Write barriers are not needed.
+		memmove(valueRet, methodRet, retSize)
+	}
+
+	// Tell the runtime it can now depend on the return values
+	// being properly initialized.
+	*retValid = true
+
+	// Clear the scratch space and put it back in the pool.
+	// This must happen after the statement above, so that the return
+	// values will always be scanned by someone.
+	typedmemclr(methodFrameType, methodFrame)
+	methodFramePool.Put(methodFrame)
+
+	// See the comment in callReflect.
+	runtime.KeepAlive(ctxt)
+
+	// Keep valueRegs alive because it may hold live pointer results.
+	// The caller (methodValueCall) has it as a stack object, which is only
+	// scanned when there is a reference to it.
+	runtime.KeepAlive(valueRegs)
+}
+
+// funcName returns the name of f, for use in error messages.
+func funcName(f func([]Value) []Value) string {
+	pc := *(*uintptr)(unsafe.Pointer(&f))
+	rf := runtime.FuncForPC(pc)
+	if rf != nil {
+		return rf.Name()
+	}
+	return "closure"
+}
+
+// Cap returns v's capacity.
+// It panics if v's Kind is not Array, Chan, Slice or pointer to Array.
+func (v Value) Cap() int {
+	// capNonSlice is split out to keep Cap inlineable for slice kinds.
+	if v.kind() == Slice {
+		return (*unsafeheader.Slice)(v.ptr).Cap
+	}
+	return v.capNonSlice()
+}
+
+func (v Value) capNonSlice() int {
+	k := v.kind()
+	switch k {
+	case Array:
+		return v.typ.Len()
+	case Chan:
+		return chancap(v.pointer())
+	case Ptr:
+		if v.typ.Elem().Kind() == Array {
+			return v.typ.Elem().Len()
+		}
+		panic("reflect: call of reflect.Value.Cap on ptr to non-array Value")
+	}
+	panic(&ValueError{"reflect.Value.Cap", v.kind()})
+}
+
+// Close closes the channel v.
+// It panics if v's Kind is not Chan.
+func (v Value) Close() {
+	v.mustBe(Chan)
+	v.mustBeExported()
+	chanclose(v.pointer())
+}
+
+// CanComplex reports whether Complex can be used without panicking.
+func (v Value) CanComplex() bool {
+	switch v.kind() {
+	case Complex64, Complex128:
+		return true
+	default:
+		return false
+	}
+}
+
+// Complex returns v's underlying value, as a complex128.
+// It panics if v's Kind is not Complex64 or Complex128
+func (v Value) Complex() complex128 {
+	k := v.kind()
+	switch k {
+	case Complex64:
+		return complex128(*(*complex64)(v.ptr))
+	case Complex128:
+		return *(*complex128)(v.ptr)
+	}
+	panic(&ValueError{"reflect.Value.Complex", v.kind()})
+}
+
+// Elem returns the value that the interface v contains
+// or that the pointer v points to.
+// It panics if v's Kind is not Interface or Pointer.
+// It returns the zero Value if v is nil.
+func (v Value) Elem() Value {
+	k := v.kind()
+	switch k {
+	case Interface:
+		var eface any
+		if v.typ.NumMethod() == 0 {
+			eface = *(*any)(v.ptr)
+		} else {
+			eface = (any)(*(*interface {
+				M()
+			})(v.ptr))
+		}
+		x := unpackEface(eface)
+		if x.flag != 0 {
+			x.flag |= v.flag.ro()
+		}
+		return x
+	case Pointer:
+		ptr := v.ptr
+		if v.flag&flagIndir != 0 {
+			if ifaceIndir(v.typ) {
+				// This is a pointer to a not-in-heap object. ptr points to a uintptr
+				// in the heap. That uintptr is the address of a not-in-heap object.
+				// In general, pointers to not-in-heap objects can be total junk.
+				// But Elem() is asking to dereference it, so the user has asserted
+				// that at least it is a valid pointer (not just an integer stored in
+				// a pointer slot). So let's check, to make sure that it isn't a pointer
+				// that the runtime will crash on if it sees it during GC or write barriers.
+				// Since it is a not-in-heap pointer, all pointers to the heap are
+				// forbidden! That makes the test pretty easy.
+				// See issue 48399.
+				if !verifyNotInHeapPtr(*(*uintptr)(ptr)) {
+					panic("reflect: reflect.Value.Elem on an invalid notinheap pointer")
+				}
+			}
+			ptr = *(*unsafe.Pointer)(ptr)
+		}
+		// The returned value's address is v's value.
+		if ptr == nil {
+			return Value{}
+		}
+		tt := (*ptrType)(unsafe.Pointer(v.typ))
+		typ := tt.elem
+		fl := v.flag&flagRO | flagIndir | flagAddr
+		fl |= flag(typ.Kind())
+		return Value{typ, ptr, fl}
+	}
+	panic(&ValueError{"reflect.Value.Elem", v.kind()})
+}
+
+// Field returns the i'th field of the struct v.
+// It panics if v's Kind is not Struct or i is out of range.
+func (v Value) Field(i int) Value {
+	if v.kind() != Struct {
+		panic(&ValueError{"reflect.Value.Field", v.kind()})
+	}
+	tt := (*structType)(unsafe.Pointer(v.typ))
+	if uint(i) >= uint(len(tt.fields)) {
+		panic("reflect: Field index out of range")
+	}
+	field := &tt.fields[i]
+	typ := field.typ
+
+	// Inherit permission bits from v, but clear flagEmbedRO.
+	fl := v.flag&(flagStickyRO|flagIndir|flagAddr) | flag(typ.Kind())
+	// Using an unexported field forces flagRO.
+	if !field.name.isExported() {
+		if field.embedded() {
+			fl |= flagEmbedRO
+		} else {
+			fl |= flagStickyRO
+		}
+	}
+	// Either flagIndir is set and v.ptr points at struct,
+	// or flagIndir is not set and v.ptr is the actual struct data.
+	// In the former case, we want v.ptr + offset.
+	// In the latter case, we must have field.offset = 0,
+	// so v.ptr + field.offset is still the correct address.
+	ptr := add(v.ptr, field.offset, "same as non-reflect &v.field")
+	return Value{typ, ptr, fl}
+}
+
+// FieldByIndex returns the nested field corresponding to index.
+// It panics if evaluation requires stepping through a nil
+// pointer or a field that is not a struct.
+func (v Value) FieldByIndex(index []int) Value {
+	if len(index) == 1 {
+		return v.Field(index[0])
+	}
+	v.mustBe(Struct)
+	for i, x := range index {
+		if i > 0 {
+			if v.Kind() == Pointer && v.typ.Elem().Kind() == Struct {
+				if v.IsNil() {
+					panic("reflect: indirection through nil pointer to embedded struct")
+				}
+				v = v.Elem()
+			}
+		}
+		v = v.Field(x)
+	}
+	return v
+}
+
+// FieldByIndexErr returns the nested field corresponding to index.
+// It returns an error if evaluation requires stepping through a nil
+// pointer, but panics if it must step through a field that
+// is not a struct.
+func (v Value) FieldByIndexErr(index []int) (Value, error) {
+	if len(index) == 1 {
+		return v.Field(index[0]), nil
+	}
+	v.mustBe(Struct)
+	for i, x := range index {
+		if i > 0 {
+			if v.Kind() == Ptr && v.typ.Elem().Kind() == Struct {
+				if v.IsNil() {
+					return Value{}, errors.New("reflect: indirection through nil pointer to embedded struct field " + v.typ.Elem().Name())
+				}
+				v = v.Elem()
+			}
+		}
+		v = v.Field(x)
+	}
+	return v, nil
+}
+
+// FieldByName returns the struct field with the given name.
+// It returns the zero Value if no field was found.
+// It panics if v's Kind is not struct.
+func (v Value) FieldByName(name string) Value {
+	v.mustBe(Struct)
+	if f, ok := v.typ.FieldByName(name); ok {
+		return v.FieldByIndex(f.Index)
+	}
+	return Value{}
+}
+
+// FieldByNameFunc returns the struct field with a name
+// that satisfies the match function.
+// It panics if v's Kind is not struct.
+// It returns the zero Value if no field was found.
+func (v Value) FieldByNameFunc(match func(string) bool) Value {
+	if f, ok := v.typ.FieldByNameFunc(match); ok {
+		return v.FieldByIndex(f.Index)
+	}
+	return Value{}
+}
+
+// CanFloat reports whether Float can be used without panicking.
+func (v Value) CanFloat() bool {
+	switch v.kind() {
+	case Float32, Float64:
+		return true
+	default:
+		return false
+	}
+}
+
+// Float returns v's underlying value, as a float64.
+// It panics if v's Kind is not Float32 or Float64
+func (v Value) Float() float64 {
+	k := v.kind()
+	switch k {
+	case Float32:
+		return float64(*(*float32)(v.ptr))
+	case Float64:
+		return *(*float64)(v.ptr)
+	}
+	panic(&ValueError{"reflect.Value.Float", v.kind()})
+}
+
+var uint8Type = TypeOf(uint8(0)).(*rtype)
+
+// Index returns v's i'th element.
+// It panics if v's Kind is not Array, Slice, or String or i is out of range.
+func (v Value) Index(i int) Value {
+	switch v.kind() {
+	case Array:
+		tt := (*arrayType)(unsafe.Pointer(v.typ))
+		if uint(i) >= uint(tt.len) {
+			panic("reflect: array index out of range")
+		}
+		typ := tt.elem
+		offset := uintptr(i) * typ.size
+
+		// Either flagIndir is set and v.ptr points at array,
+		// or flagIndir is not set and v.ptr is the actual array data.
+		// In the former case, we want v.ptr + offset.
+		// In the latter case, we must be doing Index(0), so offset = 0,
+		// so v.ptr + offset is still the correct address.
+		val := add(v.ptr, offset, "same as &v[i], i < tt.len")
+		fl := v.flag&(flagIndir|flagAddr) | v.flag.ro() | flag(typ.Kind()) // bits same as overall array
+		return Value{typ, val, fl}
+
+	case Slice:
+		// Element flag same as Elem of Pointer.
+		// Addressable, indirect, possibly read-only.
+		s := (*unsafeheader.Slice)(v.ptr)
+		if uint(i) >= uint(s.Len) {
+			panic("reflect: slice index out of range")
+		}
+		tt := (*sliceType)(unsafe.Pointer(v.typ))
+		typ := tt.elem
+		val := arrayAt(s.Data, i, typ.size, "i < s.Len")
+		fl := flagAddr | flagIndir | v.flag.ro() | flag(typ.Kind())
+		return Value{typ, val, fl}
+
+	case String:
+		s := (*unsafeheader.String)(v.ptr)
+		if uint(i) >= uint(s.Len) {
+			panic("reflect: string index out of range")
+		}
+		p := arrayAt(s.Data, i, 1, "i < s.Len")
+		fl := v.flag.ro() | flag(Uint8) | flagIndir
+		return Value{uint8Type, p, fl}
+	}
+	panic(&ValueError{"reflect.Value.Index", v.kind()})
+}
+
+// CanInt reports whether Int can be used without panicking.
+func (v Value) CanInt() bool {
+	switch v.kind() {
+	case Int, Int8, Int16, Int32, Int64:
+		return true
+	default:
+		return false
+	}
+}
+
+// Int returns v's underlying value, as an int64.
+// It panics if v's Kind is not Int, Int8, Int16, Int32, or Int64.
+func (v Value) Int() int64 {
+	k := v.kind()
+	p := v.ptr
+	switch k {
+	case Int:
+		return int64(*(*int)(p))
+	case Int8:
+		return int64(*(*int8)(p))
+	case Int16:
+		return int64(*(*int16)(p))
+	case Int32:
+		return int64(*(*int32)(p))
+	case Int64:
+		return *(*int64)(p)
+	}
+	panic(&ValueError{"reflect.Value.Int", v.kind()})
+}
+
+// CanInterface reports whether Interface can be used without panicking.
+func (v Value) CanInterface() bool {
+	if v.flag == 0 {
+		panic(&ValueError{"reflect.Value.CanInterface", Invalid})
+	}
+	return v.flag&flagRO == 0
+}
+
+// Interface returns v's current value as an interface{}.
+// It is equivalent to:
+//
+//	var i interface{} = (v's underlying value)
+//
+// It panics if the Value was obtained by accessing
+// unexported struct fields.
+func (v Value) Interface() (i any) {
+	return valueInterface(v, true)
+}
+
+func valueInterface(v Value, safe bool) any {
+	if v.flag == 0 {
+		panic(&ValueError{"reflect.Value.Interface", Invalid})
+	}
+	if safe && v.flag&flagRO != 0 {
+		// Do not allow access to unexported values via Interface,
+		// because they might be pointers that should not be
+		// writable or methods or function that should not be callable.
+		panic("reflect.Value.Interface: cannot return value obtained from unexported field or method")
+	}
+	if v.flag&flagMethod != 0 {
+		v = makeMethodValue("Interface", v)
+	}
+
+	if v.kind() == Interface {
+		// Special case: return the element inside the interface.
+		// Empty interface has one layout, all interfaces with
+		// methods have a second layout.
+		if v.NumMethod() == 0 {
+			return *(*any)(v.ptr)
+		}
+		return *(*interface {
+			M()
+		})(v.ptr)
+	}
+
+	// TODO: pass safe to packEface so we don't need to copy if safe==true?
+	return packEface(v)
+}
+
+// InterfaceData returns a pair of unspecified uintptr values.
+// It panics if v's Kind is not Interface.
+//
+// In earlier versions of Go, this function returned the interface's
+// value as a uintptr pair. As of Go 1.4, the implementation of
+// interface values precludes any defined use of InterfaceData.
+//
+// Deprecated: The memory representation of interface values is not
+// compatible with InterfaceData.
+func (v Value) InterfaceData() [2]uintptr {
+	v.mustBe(Interface)
+	// We treat this as a read operation, so we allow
+	// it even for unexported data, because the caller
+	// has to import "unsafe" to turn it into something
+	// that can be abused.
+	// Interface value is always bigger than a word; assume flagIndir.
+	return *(*[2]uintptr)(v.ptr)
+}
+
+// IsNil reports whether its argument v is nil. The argument must be
+// a chan, func, interface, map, pointer, or slice value; if it is
+// not, IsNil panics. Note that IsNil is not always equivalent to a
+// regular comparison with nil in Go. For example, if v was created
+// by calling ValueOf with an uninitialized interface variable i,
+// i==nil will be true but v.IsNil will panic as v will be the zero
+// Value.
+func (v Value) IsNil() bool {
+	k := v.kind()
+	switch k {
+	case Chan, Func, Map, Pointer, UnsafePointer:
+		if v.flag&flagMethod != 0 {
+			return false
+		}
+		ptr := v.ptr
+		if v.flag&flagIndir != 0 {
+			ptr = *(*unsafe.Pointer)(ptr)
+		}
+		return ptr == nil
+	case Interface, Slice:
+		// Both interface and slice are nil if first word is 0.
+		// Both are always bigger than a word; assume flagIndir.
+		return *(*unsafe.Pointer)(v.ptr) == nil
+	}
+	panic(&ValueError{"reflect.Value.IsNil", v.kind()})
+}
+
+// IsValid reports whether v represents a value.
+// It returns false if v is the zero Value.
+// If IsValid returns false, all other methods except String panic.
+// Most functions and methods never return an invalid Value.
+// If one does, its documentation states the conditions explicitly.
+func (v Value) IsValid() bool {
+	return v.flag != 0
+}
+
+// IsZero reports whether v is the zero value for its type.
+// It panics if the argument is invalid.
+func (v Value) IsZero() bool {
+	switch v.kind() {
+	case Bool:
+		return !v.Bool()
+	case Int, Int8, Int16, Int32, Int64:
+		return v.Int() == 0
+	case Uint, Uint8, Uint16, Uint32, Uint64, Uintptr:
+		return v.Uint() == 0
+	case Float32, Float64:
+		return math.Float64bits(v.Float()) == 0
+	case Complex64, Complex128:
+		c := v.Complex()
+		return math.Float64bits(real(c)) == 0 && math.Float64bits(imag(c)) == 0
+	case Array:
+		for i := 0; i < v.Len(); i++ {
+			if !v.Index(i).IsZero() {
+				return false
+			}
+		}
+		return true
+	case Chan, Func, Interface, Map, Pointer, Slice, UnsafePointer:
+		return v.IsNil()
+	case String:
+		return v.Len() == 0
+	case Struct:
+		for i := 0; i < v.NumField(); i++ {
+			if !v.Field(i).IsZero() {
+				return false
+			}
+		}
+		return true
+	default:
+		// This should never happens, but will act as a safeguard for
+		// later, as a default value doesn't makes sense here.
+		panic(&ValueError{"reflect.Value.IsZero", v.Kind()})
+	}
+}
+
+// Kind returns v's Kind.
+// If v is the zero Value (IsValid returns false), Kind returns Invalid.
+func (v Value) Kind() Kind {
+	return v.kind()
+}
+
+// Len returns v's length.
+// It panics if v's Kind is not Array, Chan, Map, Slice, String, or pointer to Array.
+func (v Value) Len() int {
+	// lenNonSlice is split out to keep Len inlineable for slice kinds.
+	if v.kind() == Slice {
+		return (*unsafeheader.Slice)(v.ptr).Len
+	}
+	return v.lenNonSlice()
+}
+
+func (v Value) lenNonSlice() int {
+	switch k := v.kind(); k {
+	case Array:
+		tt := (*arrayType)(unsafe.Pointer(v.typ))
+		return int(tt.len)
+	case Chan:
+		return chanlen(v.pointer())
+	case Map:
+		return maplen(v.pointer())
+	case String:
+		// String is bigger than a word; assume flagIndir.
+		return (*unsafeheader.String)(v.ptr).Len
+	case Ptr:
+		if v.typ.Elem().Kind() == Array {
+			return v.typ.Elem().Len()
+		}
+		panic("reflect: call of reflect.Value.Len on ptr to non-array Value")
+	}
+	panic(&ValueError{"reflect.Value.Len", v.kind()})
+}
+
+var stringType = TypeOf("").(*rtype)
+
+// MapIndex returns the value associated with key in the map v.
+// It panics if v's Kind is not Map.
+// It returns the zero Value if key is not found in the map or if v represents a nil map.
+// As in Go, the key's value must be assignable to the map's key type.
+func (v Value) MapIndex(key Value) Value {
+	v.mustBe(Map)
+	tt := (*mapType)(unsafe.Pointer(v.typ))
+
+	// Do not require key to be exported, so that DeepEqual
+	// and other programs can use all the keys returned by
+	// MapKeys as arguments to MapIndex. If either the map
+	// or the key is unexported, though, the result will be
+	// considered unexported. This is consistent with the
+	// behavior for structs, which allow read but not write
+	// of unexported fields.
+
+	var e unsafe.Pointer
+	if (tt.key == stringType || key.kind() == String) && tt.key == key.typ && tt.elem.size <= maxValSize {
+		k := *(*string)(key.ptr)
+		e = mapaccess_faststr(v.typ, v.pointer(), k)
+	} else {
+		key = key.assignTo("reflect.Value.MapIndex", tt.key, nil)
+		var k unsafe.Pointer
+		if key.flag&flagIndir != 0 {
+			k = key.ptr
+		} else {
+			k = unsafe.Pointer(&key.ptr)
+		}
+		e = mapaccess(v.typ, v.pointer(), k)
+	}
+	if e == nil {
+		return Value{}
+	}
+	typ := tt.elem
+	fl := (v.flag | key.flag).ro()
+	fl |= flag(typ.Kind())
+	return copyVal(typ, fl, e)
+}
+
+// MapKeys returns a slice containing all the keys present in the map,
+// in unspecified order.
+// It panics if v's Kind is not Map.
+// It returns an empty slice if v represents a nil map.
+func (v Value) MapKeys() []Value {
+	v.mustBe(Map)
+	tt := (*mapType)(unsafe.Pointer(v.typ))
+	keyType := tt.key
+
+	fl := v.flag.ro() | flag(keyType.Kind())
+
+	m := v.pointer()
+	mlen := int(0)
+	if m != nil {
+		mlen = maplen(m)
+	}
+	var it hiter
+	mapiterinit(v.typ, m, &it)
+	a := make([]Value, mlen)
+	var i int
+	for i = 0; i < len(a); i++ {
+		key := mapiterkey(&it)
+		if key == nil {
+			// Someone deleted an entry from the map since we
+			// called maplen above. It's a data race, but nothing
+			// we can do about it.
+			break
+		}
+		a[i] = copyVal(keyType, fl, key)
+		mapiternext(&it)
+	}
+	return a[:i]
+}
+
+// hiter's structure matches runtime.hiter's structure.
+// Having a clone here allows us to embed a map iterator
+// inside type MapIter so that MapIters can be re-used
+// without doing any allocations.
+type hiter struct {
+	key         unsafe.Pointer
+	elem        unsafe.Pointer
+	t           unsafe.Pointer
+	h           unsafe.Pointer
+	buckets     unsafe.Pointer
+	bptr        unsafe.Pointer
+	overflow    *[]unsafe.Pointer
+	oldoverflow *[]unsafe.Pointer
+	startBucket uintptr
+	offset      uint8
+	wrapped     bool
+	B           uint8
+	i           uint8
+	bucket      uintptr
+	checkBucket uintptr
+}
+
+func (h *hiter) initialized() bool {
+	return h.t != nil
+}
+
+// A MapIter is an iterator for ranging over a map.
+// See Value.MapRange.
+type MapIter struct {
+	m     Value
+	hiter hiter
+}
+
+// Key returns the key of iter's current map entry.
+func (iter *MapIter) Key() Value {
+	if !iter.hiter.initialized() {
+		panic("MapIter.Key called before Next")
+	}
+	iterkey := mapiterkey(&iter.hiter)
+	if iterkey == nil {
+		panic("MapIter.Key called on exhausted iterator")
+	}
+
+	t := (*mapType)(unsafe.Pointer(iter.m.typ))
+	ktype := t.key
+	return copyVal(ktype, iter.m.flag.ro()|flag(ktype.Kind()), iterkey)
+}
+
+// SetIterKey assigns to v the key of iter's current map entry.
+// It is equivalent to v.Set(iter.Key()), but it avoids allocating a new Value.
+// As in Go, the key must be assignable to v's type.
+func (v Value) SetIterKey(iter *MapIter) {
+	if !iter.hiter.initialized() {
+		panic("reflect: Value.SetIterKey called before Next")
+	}
+	iterkey := mapiterkey(&iter.hiter)
+	if iterkey == nil {
+		panic("reflect: Value.SetIterKey called on exhausted iterator")
+	}
+
+	v.mustBeAssignable()
+	var target unsafe.Pointer
+	if v.kind() == Interface {
+		target = v.ptr
+	}
+
+	t := (*mapType)(unsafe.Pointer(iter.m.typ))
+	ktype := t.key
+
+	key := Value{ktype, iterkey, iter.m.flag | flag(ktype.Kind()) | flagIndir}
+	key = key.assignTo("reflect.MapIter.SetKey", v.typ, target)
+	typedmemmove(v.typ, v.ptr, key.ptr)
+}
+
+// Value returns the value of iter's current map entry.
+func (iter *MapIter) Value() Value {
+	if !iter.hiter.initialized() {
+		panic("MapIter.Value called before Next")
+	}
+	iterelem := mapiterelem(&iter.hiter)
+	if iterelem == nil {
+		panic("MapIter.Value called on exhausted iterator")
+	}
+
+	t := (*mapType)(unsafe.Pointer(iter.m.typ))
+	vtype := t.elem
+	return copyVal(vtype, iter.m.flag.ro()|flag(vtype.Kind()), iterelem)
+}
+
+// SetIterValue assigns to v the value of iter's current map entry.
+// It is equivalent to v.Set(iter.Value()), but it avoids allocating a new Value.
+// As in Go, the value must be assignable to v's type.
+func (v Value) SetIterValue(iter *MapIter) {
+	if !iter.hiter.initialized() {
+		panic("reflect: Value.SetIterValue called before Next")
+	}
+	iterelem := mapiterelem(&iter.hiter)
+	if iterelem == nil {
+		panic("reflect: Value.SetIterValue called on exhausted iterator")
+	}
+
+	v.mustBeAssignable()
+	var target unsafe.Pointer
+	if v.kind() == Interface {
+		target = v.ptr
+	}
+
+	t := (*mapType)(unsafe.Pointer(iter.m.typ))
+	vtype := t.elem
+
+	elem := Value{vtype, iterelem, iter.m.flag | flag(vtype.Kind()) | flagIndir}
+	elem = elem.assignTo("reflect.MapIter.SetValue", v.typ, target)
+	typedmemmove(v.typ, v.ptr, elem.ptr)
+}
+
+// Next advances the map iterator and reports whether there is another
+// entry. It returns false when iter is exhausted; subsequent
+// calls to Key, Value, or Next will panic.
+func (iter *MapIter) Next() bool {
+	if !iter.m.IsValid() {
+		panic("MapIter.Next called on an iterator that does not have an associated map Value")
+	}
+	if !iter.hiter.initialized() {
+		mapiterinit(iter.m.typ, iter.m.pointer(), &iter.hiter)
+	} else {
+		if mapiterkey(&iter.hiter) == nil {
+			panic("MapIter.Next called on exhausted iterator")
+		}
+		mapiternext(&iter.hiter)
+	}
+	return mapiterkey(&iter.hiter) != nil
+}
+
+// Reset modifies iter to iterate over v.
+// It panics if v's Kind is not Map and v is not the zero Value.
+// Reset(Value{}) causes iter to not to refer to any map,
+// which may allow the previously iterated-over map to be garbage collected.
+func (iter *MapIter) Reset(v Value) {
+	if v.IsValid() {
+		v.mustBe(Map)
+	}
+	iter.m = v
+	iter.hiter = hiter{}
+}
+
+// MapRange returns a range iterator for a map.
+// It panics if v's Kind is not Map.
+//
+// Call Next to advance the iterator, and Key/Value to access each entry.
+// Next returns false when the iterator is exhausted.
+// MapRange follows the same iteration semantics as a range statement.
+//
+// Example:
+//
+//	iter := reflect.ValueOf(m).MapRange()
+//	for iter.Next() {
+//		k := iter.Key()
+//		v := iter.Value()
+//		...
+//	}
+func (v Value) MapRange() *MapIter {
+	// This is inlinable to take advantage of "function outlining".
+	// The allocation of MapIter can be stack allocated if the caller
+	// does not allow it to escape.
+	// See https://blog.filippo.io/efficient-go-apis-with-the-inliner/
+	if v.kind() != Map {
+		v.panicNotMap()
+	}
+	return &MapIter{m: v}
+}
+
+func (f flag) panicNotMap() {
+	f.mustBe(Map)
+}
+
+// copyVal returns a Value containing the map key or value at ptr,
+// allocating a new variable as needed.
+func copyVal(typ *rtype, fl flag, ptr unsafe.Pointer) Value {
+	if ifaceIndir(typ) {
+		// Copy result so future changes to the map
+		// won't change the underlying value.
+		c := unsafe_New(typ)
+		typedmemmove(typ, c, ptr)
+		return Value{typ, c, fl | flagIndir}
+	}
+	return Value{typ, *(*unsafe.Pointer)(ptr), fl}
+}
+
+// Method returns a function value corresponding to v's i'th method.
+// The arguments to a Call on the returned function should not include
+// a receiver; the returned function will always use v as the receiver.
+// Method panics if i is out of range or if v is a nil interface value.
+func (v Value) Method(i int) Value {
+	if v.typ == nil {
+		panic(&ValueError{"reflect.Value.Method", Invalid})
+	}
+	if v.flag&flagMethod != 0 || uint(i) >= uint(v.typ.NumMethod()) {
+		panic("reflect: Method index out of range")
+	}
+	if v.typ.Kind() == Interface && v.IsNil() {
+		panic("reflect: Method on nil interface value")
+	}
+	fl := v.flag.ro() | (v.flag & flagIndir)
+	fl |= flag(Func)
+	fl |= flag(i)<<flagMethodShift | flagMethod
+	return Value{v.typ, v.ptr, fl}
+}
+
+// NumMethod returns the number of methods in the value's method set.
+//
+// For a non-interface type, it returns the number of exported methods.
+//
+// For an interface type, it returns the number of exported and unexported methods.
+func (v Value) NumMethod() int {
+	if v.typ == nil {
+		panic(&ValueError{"reflect.Value.NumMethod", Invalid})
+	}
+	if v.flag&flagMethod != 0 {
+		return 0
+	}
+	return v.typ.NumMethod()
+}
+
+// MethodByName returns a function value corresponding to the method
+// of v with the given name.
+// The arguments to a Call on the returned function should not include
+// a receiver; the returned function will always use v as the receiver.
+// It returns the zero Value if no method was found.
+func (v Value) MethodByName(name string) Value {
+	if v.typ == nil {
+		panic(&ValueError{"reflect.Value.MethodByName", Invalid})
+	}
+	if v.flag&flagMethod != 0 {
+		return Value{}
+	}
+	m, ok := v.typ.MethodByName(name)
+	if !ok {
+		return Value{}
+	}
+	return v.Method(m.Index)
+}
+
+// NumField returns the number of fields in the struct v.
+// It panics if v's Kind is not Struct.
+func (v Value) NumField() int {
+	v.mustBe(Struct)
+	tt := (*structType)(unsafe.Pointer(v.typ))
+	return len(tt.fields)
+}
+
+// OverflowComplex reports whether the complex128 x cannot be represented by v's type.
+// It panics if v's Kind is not Complex64 or Complex128.
+func (v Value) OverflowComplex(x complex128) bool {
+	k := v.kind()
+	switch k {
+	case Complex64:
+		return overflowFloat32(real(x)) || overflowFloat32(imag(x))
+	case Complex128:
+		return false
+	}
+	panic(&ValueError{"reflect.Value.OverflowComplex", v.kind()})
+}
+
+// OverflowFloat reports whether the float64 x cannot be represented by v's type.
+// It panics if v's Kind is not Float32 or Float64.
+func (v Value) OverflowFloat(x float64) bool {
+	k := v.kind()
+	switch k {
+	case Float32:
+		return overflowFloat32(x)
+	case Float64:
+		return false
+	}
+	panic(&ValueError{"reflect.Value.OverflowFloat", v.kind()})
+}
+
+func overflowFloat32(x float64) bool {
+	if x < 0 {
+		x = -x
+	}
+	return math.MaxFloat32 < x && x <= math.MaxFloat64
+}
+
+// OverflowInt reports whether the int64 x cannot be represented by v's type.
+// It panics if v's Kind is not Int, Int8, Int16, Int32, or Int64.
+func (v Value) OverflowInt(x int64) bool {
+	k := v.kind()
+	switch k {
+	case Int, Int8, Int16, Int32, Int64:
+		bitSize := v.typ.size * 8
+		trunc := (x << (64 - bitSize)) >> (64 - bitSize)
+		return x != trunc
+	}
+	panic(&ValueError{"reflect.Value.OverflowInt", v.kind()})
+}
+
+// OverflowUint reports whether the uint64 x cannot be represented by v's type.
+// It panics if v's Kind is not Uint, Uintptr, Uint8, Uint16, Uint32, or Uint64.
+func (v Value) OverflowUint(x uint64) bool {
+	k := v.kind()
+	switch k {
+	case Uint, Uintptr, Uint8, Uint16, Uint32, Uint64:
+		bitSize := v.typ.size * 8
+		trunc := (x << (64 - bitSize)) >> (64 - bitSize)
+		return x != trunc
+	}
+	panic(&ValueError{"reflect.Value.OverflowUint", v.kind()})
+}
+
+//go:nocheckptr
+// This prevents inlining Value.Pointer when -d=checkptr is enabled,
+// which ensures cmd/compile can recognize unsafe.Pointer(v.Pointer())
+// and make an exception.
+
+// Pointer returns v's value as a uintptr.
+// It returns uintptr instead of unsafe.Pointer so that
+// code using reflect cannot obtain unsafe.Pointers
+// without importing the unsafe package explicitly.
+// It panics if v's Kind is not Chan, Func, Map, Pointer, Slice, or UnsafePointer.
+//
+// If v's Kind is Func, the returned pointer is an underlying
+// code pointer, but not necessarily enough to identify a
+// single function uniquely. The only guarantee is that the
+// result is zero if and only if v is a nil func Value.
+//
+// If v's Kind is Slice, the returned pointer is to the first
+// element of the slice. If the slice is nil the returned value
+// is 0.  If the slice is empty but non-nil the return value is non-zero.
+//
+// It's preferred to use uintptr(Value.UnsafePointer()) to get the equivalent result.
+func (v Value) Pointer() uintptr {
+	k := v.kind()
+	switch k {
+	case Pointer:
+		if v.typ.ptrdata == 0 {
+			val := *(*uintptr)(v.ptr)
+			// Since it is a not-in-heap pointer, all pointers to the heap are
+			// forbidden! See comment in Value.Elem and issue #48399.
+			if !verifyNotInHeapPtr(val) {
+				panic("reflect: reflect.Value.Pointer on an invalid notinheap pointer")
+			}
+			return val
+		}
+		fallthrough
+	case Chan, Map, UnsafePointer:
+		return uintptr(v.pointer())
+	case Func:
+		if v.flag&flagMethod != 0 {
+			// As the doc comment says, the returned pointer is an
+			// underlying code pointer but not necessarily enough to
+			// identify a single function uniquely. All method expressions
+			// created via reflect have the same underlying code pointer,
+			// so their Pointers are equal. The function used here must
+			// match the one used in makeMethodValue.
+			return methodValueCallCodePtr()
+		}
+		p := v.pointer()
+		// Non-nil func value points at data block.
+		// First word of data block is actual code.
+		if p != nil {
+			p = *(*unsafe.Pointer)(p)
+		}
+		return uintptr(p)
+
+	case Slice:
+		return (*SliceHeader)(v.ptr).Data
+	}
+	panic(&ValueError{"reflect.Value.Pointer", v.kind()})
+}
+
+// Recv receives and returns a value from the channel v.
+// It panics if v's Kind is not Chan.
+// The receive blocks until a value is ready.
+// The boolean value ok is true if the value x corresponds to a send
+// on the channel, false if it is a zero value received because the channel is closed.
+func (v Value) Recv() (x Value, ok bool) {
+	v.mustBe(Chan)
+	v.mustBeExported()
+	return v.recv(false)
+}
+
+// internal recv, possibly non-blocking (nb).
+// v is known to be a channel.
+func (v Value) recv(nb bool) (val Value, ok bool) {
+	tt := (*chanType)(unsafe.Pointer(v.typ))
+	if ChanDir(tt.dir)&RecvDir == 0 {
+		panic("reflect: recv on send-only channel")
+	}
+	t := tt.elem
+	val = Value{t, nil, flag(t.Kind())}
+	var p unsafe.Pointer
+	if ifaceIndir(t) {
+		p = unsafe_New(t)
+		val.ptr = p
+		val.flag |= flagIndir
+	} else {
+		p = unsafe.Pointer(&val.ptr)
+	}
+	selected, ok := chanrecv(v.pointer(), nb, p)
+	if !selected {
+		val = Value{}
+	}
+	return
+}
+
+// Send sends x on the channel v.
+// It panics if v's kind is not Chan or if x's type is not the same type as v's element type.
+// As in Go, x's value must be assignable to the channel's element type.
+func (v Value) Send(x Value) {
+	v.mustBe(Chan)
+	v.mustBeExported()
+	v.send(x, false)
+}
+
+// internal send, possibly non-blocking.
+// v is known to be a channel.
+func (v Value) send(x Value, nb bool) (selected bool) {
+	tt := (*chanType)(unsafe.Pointer(v.typ))
+	if ChanDir(tt.dir)&SendDir == 0 {
+		panic("reflect: send on recv-only channel")
+	}
+	x.mustBeExported()
+	x = x.assignTo("reflect.Value.Send", tt.elem, nil)
+	var p unsafe.Pointer
+	if x.flag&flagIndir != 0 {
+		p = x.ptr
+	} else {
+		p = unsafe.Pointer(&x.ptr)
+	}
+	return chansend(v.pointer(), p, nb)
+}
+
+// Set assigns x to the value v.
+// It panics if CanSet returns false.
+// As in Go, x's value must be assignable to v's type.
+func (v Value) Set(x Value) {
+	v.mustBeAssignable()
+	x.mustBeExported() // do not let unexported x leak
+	var target unsafe.Pointer
+	if v.kind() == Interface {
+		target = v.ptr
+	}
+	x = x.assignTo("reflect.Set", v.typ, target)
+	if x.flag&flagIndir != 0 {
+		if x.ptr == unsafe.Pointer(&zeroVal[0]) {
+			typedmemclr(v.typ, v.ptr)
+		} else {
+			typedmemmove(v.typ, v.ptr, x.ptr)
+		}
+	} else {
+		*(*unsafe.Pointer)(v.ptr) = x.ptr
+	}
+}
+
+// SetBool sets v's underlying value.
+// It panics if v's Kind is not Bool or if CanSet() is false.
+func (v Value) SetBool(x bool) {
+	v.mustBeAssignable()
+	v.mustBe(Bool)
+	*(*bool)(v.ptr) = x
+}
+
+// SetBytes sets v's underlying value.
+// It panics if v's underlying value is not a slice of bytes.
+func (v Value) SetBytes(x []byte) {
+	v.mustBeAssignable()
+	v.mustBe(Slice)
+	if v.typ.Elem().Kind() != Uint8 {
+		panic("reflect.Value.SetBytes of non-byte slice")
+	}
+	*(*[]byte)(v.ptr) = x
+}
+
+// setRunes sets v's underlying value.
+// It panics if v's underlying value is not a slice of runes (int32s).
+func (v Value) setRunes(x []rune) {
+	v.mustBeAssignable()
+	v.mustBe(Slice)
+	if v.typ.Elem().Kind() != Int32 {
+		panic("reflect.Value.setRunes of non-rune slice")
+	}
+	*(*[]rune)(v.ptr) = x
+}
+
+// SetComplex sets v's underlying value to x.
+// It panics if v's Kind is not Complex64 or Complex128, or if CanSet() is false.
+func (v Value) SetComplex(x complex128) {
+	v.mustBeAssignable()
+	switch k := v.kind(); k {
+	default:
+		panic(&ValueError{"reflect.Value.SetComplex", v.kind()})
+	case Complex64:
+		*(*complex64)(v.ptr) = complex64(x)
+	case Complex128:
+		*(*complex128)(v.ptr) = x
+	}
+}
+
+// SetFloat sets v's underlying value to x.
+// It panics if v's Kind is not Float32 or Float64, or if CanSet() is false.
+func (v Value) SetFloat(x float64) {
+	v.mustBeAssignable()
+	switch k := v.kind(); k {
+	default:
+		panic(&ValueError{"reflect.Value.SetFloat", v.kind()})
+	case Float32:
+		*(*float32)(v.ptr) = float32(x)
+	case Float64:
+		*(*float64)(v.ptr) = x
+	}
+}
+
+// SetInt sets v's underlying value to x.
+// It panics if v's Kind is not Int, Int8, Int16, Int32, or Int64, or if CanSet() is false.
+func (v Value) SetInt(x int64) {
+	v.mustBeAssignable()
+	switch k := v.kind(); k {
+	default:
+		panic(&ValueError{"reflect.Value.SetInt", v.kind()})
+	case Int:
+		*(*int)(v.ptr) = int(x)
+	case Int8:
+		*(*int8)(v.ptr) = int8(x)
+	case Int16:
+		*(*int16)(v.ptr) = int16(x)
+	case Int32:
+		*(*int32)(v.ptr) = int32(x)
+	case Int64:
+		*(*int64)(v.ptr) = x
+	}
+}
+
+// SetLen sets v's length to n.
+// It panics if v's Kind is not Slice or if n is negative or
+// greater than the capacity of the slice.
+func (v Value) SetLen(n int) {
+	v.mustBeAssignable()
+	v.mustBe(Slice)
+	s := (*unsafeheader.Slice)(v.ptr)
+	if uint(n) > uint(s.Cap) {
+		panic("reflect: slice length out of range in SetLen")
+	}
+	s.Len = n
+}
+
+// SetCap sets v's capacity to n.
+// It panics if v's Kind is not Slice or if n is smaller than the length or
+// greater than the capacity of the slice.
+func (v Value) SetCap(n int) {
+	v.mustBeAssignable()
+	v.mustBe(Slice)
+	s := (*unsafeheader.Slice)(v.ptr)
+	if n < s.Len || n > s.Cap {
+		panic("reflect: slice capacity out of range in SetCap")
+	}
+	s.Cap = n
+}
+
+// SetMapIndex sets the element associated with key in the map v to elem.
+// It panics if v's Kind is not Map.
+// If elem is the zero Value, SetMapIndex deletes the key from the map.
+// Otherwise if v holds a nil map, SetMapIndex will panic.
+// As in Go, key's elem must be assignable to the map's key type,
+// and elem's value must be assignable to the map's elem type.
+func (v Value) SetMapIndex(key, elem Value) {
+	v.mustBe(Map)
+	v.mustBeExported()
+	key.mustBeExported()
+	tt := (*mapType)(unsafe.Pointer(v.typ))
+
+	if (tt.key == stringType || key.kind() == String) && tt.key == key.typ && tt.elem.size <= maxValSize {
+		k := *(*string)(key.ptr)
+		if elem.typ == nil {
+			mapdelete_faststr(v.typ, v.pointer(), k)
+			return
+		}
+		elem.mustBeExported()
+		elem = elem.assignTo("reflect.Value.SetMapIndex", tt.elem, nil)
+		var e unsafe.Pointer
+		if elem.flag&flagIndir != 0 {
+			e = elem.ptr
+		} else {
+			e = unsafe.Pointer(&elem.ptr)
+		}
+		mapassign_faststr(v.typ, v.pointer(), k, e)
+		return
+	}
+
+	key = key.assignTo("reflect.Value.SetMapIndex", tt.key, nil)
+	var k unsafe.Pointer
+	if key.flag&flagIndir != 0 {
+		k = key.ptr
+	} else {
+		k = unsafe.Pointer(&key.ptr)
+	}
+	if elem.typ == nil {
+		mapdelete(v.typ, v.pointer(), k)
+		return
+	}
+	elem.mustBeExported()
+	elem = elem.assignTo("reflect.Value.SetMapIndex", tt.elem, nil)
+	var e unsafe.Pointer
+	if elem.flag&flagIndir != 0 {
+		e = elem.ptr
+	} else {
+		e = unsafe.Pointer(&elem.ptr)
+	}
+	mapassign(v.typ, v.pointer(), k, e)
+}
+
+// SetUint sets v's underlying value to x.
+// It panics if v's Kind is not Uint, Uintptr, Uint8, Uint16, Uint32, or Uint64, or if CanSet() is false.
+func (v Value) SetUint(x uint64) {
+	v.mustBeAssignable()
+	switch k := v.kind(); k {
+	default:
+		panic(&ValueError{"reflect.Value.SetUint", v.kind()})
+	case Uint:
+		*(*uint)(v.ptr) = uint(x)
+	case Uint8:
+		*(*uint8)(v.ptr) = uint8(x)
+	case Uint16:
+		*(*uint16)(v.ptr) = uint16(x)
+	case Uint32:
+		*(*uint32)(v.ptr) = uint32(x)
+	case Uint64:
+		*(*uint64)(v.ptr) = x
+	case Uintptr:
+		*(*uintptr)(v.ptr) = uintptr(x)
+	}
+}
+
+// SetPointer sets the unsafe.Pointer value v to x.
+// It panics if v's Kind is not UnsafePointer.
+func (v Value) SetPointer(x unsafe.Pointer) {
+	v.mustBeAssignable()
+	v.mustBe(UnsafePointer)
+	*(*unsafe.Pointer)(v.ptr) = x
+}
+
+// SetString sets v's underlying value to x.
+// It panics if v's Kind is not String or if CanSet() is false.
+func (v Value) SetString(x string) {
+	v.mustBeAssignable()
+	v.mustBe(String)
+	*(*string)(v.ptr) = x
+}
+
+// Slice returns v[i:j].
+// It panics if v's Kind is not Array, Slice or String, or if v is an unaddressable array,
+// or if the indexes are out of bounds.
+func (v Value) Slice(i, j int) Value {
+	var (
+		cap  int
+		typ  *sliceType
+		base unsafe.Pointer
+	)
+	switch kind := v.kind(); kind {
+	default:
+		panic(&ValueError{"reflect.Value.Slice", v.kind()})
+
+	case Array:
+		if v.flag&flagAddr == 0 {
+			panic("reflect.Value.Slice: slice of unaddressable array")
+		}
+		tt := (*arrayType)(unsafe.Pointer(v.typ))
+		cap = int(tt.len)
+		typ = (*sliceType)(unsafe.Pointer(tt.slice))
+		base = v.ptr
+
+	case Slice:
+		typ = (*sliceType)(unsafe.Pointer(v.typ))
+		s := (*unsafeheader.Slice)(v.ptr)
+		base = s.Data
+		cap = s.Cap
+
+	case String:
+		s := (*unsafeheader.String)(v.ptr)
+		if i < 0 || j < i || j > s.Len {
+			panic("reflect.Value.Slice: string slice index out of bounds")
+		}
+		var t unsafeheader.String
+		if i < s.Len {
+			t = unsafeheader.String{Data: arrayAt(s.Data, i, 1, "i < s.Len"), Len: j - i}
+		}
+		return Value{v.typ, unsafe.Pointer(&t), v.flag}
+	}
+
+	if i < 0 || j < i || j > cap {
+		panic("reflect.Value.Slice: slice index out of bounds")
+	}
+
+	// Declare slice so that gc can see the base pointer in it.
+	var x []unsafe.Pointer
+
+	// Reinterpret as *unsafeheader.Slice to edit.
+	s := (*unsafeheader.Slice)(unsafe.Pointer(&x))
+	s.Len = j - i
+	s.Cap = cap - i
+	if cap-i > 0 {
+		s.Data = arrayAt(base, i, typ.elem.Size(), "i < cap")
+	} else {
+		// do not advance pointer, to avoid pointing beyond end of slice
+		s.Data = base
+	}
+
+	fl := v.flag.ro() | flagIndir | flag(Slice)
+	return Value{typ.common(), unsafe.Pointer(&x), fl}
+}
+
+// Slice3 is the 3-index form of the slice operation: it returns v[i:j:k].
+// It panics if v's Kind is not Array or Slice, or if v is an unaddressable array,
+// or if the indexes are out of bounds.
+func (v Value) Slice3(i, j, k int) Value {
+	var (
+		cap  int
+		typ  *sliceType
+		base unsafe.Pointer
+	)
+	switch kind := v.kind(); kind {
+	default:
+		panic(&ValueError{"reflect.Value.Slice3", v.kind()})
+
+	case Array:
+		if v.flag&flagAddr == 0 {
+			panic("reflect.Value.Slice3: slice of unaddressable array")
+		}
+		tt := (*arrayType)(unsafe.Pointer(v.typ))
+		cap = int(tt.len)
+		typ = (*sliceType)(unsafe.Pointer(tt.slice))
+		base = v.ptr
+
+	case Slice:
+		typ = (*sliceType)(unsafe.Pointer(v.typ))
+		s := (*unsafeheader.Slice)(v.ptr)
+		base = s.Data
+		cap = s.Cap
+	}
+
+	if i < 0 || j < i || k < j || k > cap {
+		panic("reflect.Value.Slice3: slice index out of bounds")
+	}
+
+	// Declare slice so that the garbage collector
+	// can see the base pointer in it.
+	var x []unsafe.Pointer
+
+	// Reinterpret as *unsafeheader.Slice to edit.
+	s := (*unsafeheader.Slice)(unsafe.Pointer(&x))
+	s.Len = j - i
+	s.Cap = k - i
+	if k-i > 0 {
+		s.Data = arrayAt(base, i, typ.elem.Size(), "i < k <= cap")
+	} else {
+		// do not advance pointer, to avoid pointing beyond end of slice
+		s.Data = base
+	}
+
+	fl := v.flag.ro() | flagIndir | flag(Slice)
+	return Value{typ.common(), unsafe.Pointer(&x), fl}
+}
+
+// String returns the string v's underlying value, as a string.
+// String is a special case because of Go's String method convention.
+// Unlike the other getters, it does not panic if v's Kind is not String.
+// Instead, it returns a string of the form "<T value>" where T is v's type.
+// The fmt package treats Values specially. It does not call their String
+// method implicitly but instead prints the concrete values they hold.
+func (v Value) String() string {
+	// stringNonString is split out to keep String inlineable for string kinds.
+	if v.kind() == String {
+		return *(*string)(v.ptr)
+	}
+	return v.stringNonString()
+}
+
+func (v Value) stringNonString() string {
+	if v.kind() == Invalid {
+		return "<invalid Value>"
+	}
+	// If you call String on a reflect.Value of other type, it's better to
+	// print something than to panic. Useful in debugging.
+	return "<" + v.Type().String() + " Value>"
+}
+
+// TryRecv attempts to receive a value from the channel v but will not block.
+// It panics if v's Kind is not Chan.
+// If the receive delivers a value, x is the transferred value and ok is true.
+// If the receive cannot finish without blocking, x is the zero Value and ok is false.
+// If the channel is closed, x is the zero value for the channel's element type and ok is false.
+func (v Value) TryRecv() (x Value, ok bool) {
+	v.mustBe(Chan)
+	v.mustBeExported()
+	return v.recv(true)
+}
+
+// TrySend attempts to send x on the channel v but will not block.
+// It panics if v's Kind is not Chan.
+// It reports whether the value was sent.
+// As in Go, x's value must be assignable to the channel's element type.
+func (v Value) TrySend(x Value) bool {
+	v.mustBe(Chan)
+	v.mustBeExported()
+	return v.send(x, true)
+}
+
+// Type returns v's type.
+func (v Value) Type() Type {
+	if v.flag != 0 && v.flag&flagMethod == 0 {
+		return v.typ
+	}
+	return v.typeSlow()
+}
+
+func (v Value) typeSlow() Type {
+	if v.flag == 0 {
+		panic(&ValueError{"reflect.Value.Type", Invalid})
+	}
+	if v.flag&flagMethod == 0 {
+		return v.typ
+	}
+
+	// Method value.
+	// v.typ describes the receiver, not the method type.
+	i := int(v.flag) >> flagMethodShift
+	if v.typ.Kind() == Interface {
+		// Method on interface.
+		tt := (*interfaceType)(unsafe.Pointer(v.typ))
+		if uint(i) >= uint(len(tt.methods)) {
+			panic("reflect: internal error: invalid method index")
+		}
+		m := &tt.methods[i]
+		return v.typ.typeOff(m.typ)
+	}
+	// Method on concrete type.
+	ms := v.typ.exportedMethods()
+	if uint(i) >= uint(len(ms)) {
+		panic("reflect: internal error: invalid method index")
+	}
+	m := ms[i]
+	return v.typ.typeOff(m.mtyp)
+}
+
+// CanUint reports whether Uint can be used without panicking.
+func (v Value) CanUint() bool {
+	switch v.kind() {
+	case Uint, Uint8, Uint16, Uint32, Uint64, Uintptr:
+		return true
+	default:
+		return false
+	}
+}
+
+// Uint returns v's underlying value, as a uint64.
+// It panics if v's Kind is not Uint, Uintptr, Uint8, Uint16, Uint32, or Uint64.
+func (v Value) Uint() uint64 {
+	k := v.kind()
+	p := v.ptr
+	switch k {
+	case Uint:
+		return uint64(*(*uint)(p))
+	case Uint8:
+		return uint64(*(*uint8)(p))
+	case Uint16:
+		return uint64(*(*uint16)(p))
+	case Uint32:
+		return uint64(*(*uint32)(p))
+	case Uint64:
+		return *(*uint64)(p)
+	case Uintptr:
+		return uint64(*(*uintptr)(p))
+	}
+	panic(&ValueError{"reflect.Value.Uint", v.kind()})
+}
+
+//go:nocheckptr
+// This prevents inlining Value.UnsafeAddr when -d=checkptr is enabled,
+// which ensures cmd/compile can recognize unsafe.Pointer(v.UnsafeAddr())
+// and make an exception.
+
+// UnsafeAddr returns a pointer to v's data, as a uintptr.
+// It is for advanced clients that also import the "unsafe" package.
+// It panics if v is not addressable.
+//
+// It's preferred to use uintptr(Value.Addr().UnsafePointer()) to get the equivalent result.
+func (v Value) UnsafeAddr() uintptr {
+	if v.typ == nil {
+		panic(&ValueError{"reflect.Value.UnsafeAddr", Invalid})
+	}
+	if v.flag&flagAddr == 0 {
+		panic("reflect.Value.UnsafeAddr of unaddressable value")
+	}
+	return uintptr(v.ptr)
+}
+
+// UnsafePointer returns v's value as a unsafe.Pointer.
+// It panics if v's Kind is not Chan, Func, Map, Pointer, Slice, or UnsafePointer.
+//
+// If v's Kind is Func, the returned pointer is an underlying
+// code pointer, but not necessarily enough to identify a
+// single function uniquely. The only guarantee is that the
+// result is zero if and only if v is a nil func Value.
+//
+// If v's Kind is Slice, the returned pointer is to the first
+// element of the slice. If the slice is nil the returned value
+// is nil.  If the slice is empty but non-nil the return value is non-nil.
+func (v Value) UnsafePointer() unsafe.Pointer {
+	k := v.kind()
+	switch k {
+	case Pointer:
+		if v.typ.ptrdata == 0 {
+			// Since it is a not-in-heap pointer, all pointers to the heap are
+			// forbidden! See comment in Value.Elem and issue #48399.
+			if !verifyNotInHeapPtr(*(*uintptr)(v.ptr)) {
+				panic("reflect: reflect.Value.UnsafePointer on an invalid notinheap pointer")
+			}
+			return *(*unsafe.Pointer)(v.ptr)
+		}
+		fallthrough
+	case Chan, Map, UnsafePointer:
+		return v.pointer()
+	case Func:
+		if v.flag&flagMethod != 0 {
+			// As the doc comment says, the returned pointer is an
+			// underlying code pointer but not necessarily enough to
+			// identify a single function uniquely. All method expressions
+			// created via reflect have the same underlying code pointer,
+			// so their Pointers are equal. The function used here must
+			// match the one used in makeMethodValue.
+			code := methodValueCallCodePtr()
+			return *(*unsafe.Pointer)(unsafe.Pointer(&code))
+		}
+		p := v.pointer()
+		// Non-nil func value points at data block.
+		// First word of data block is actual code.
+		if p != nil {
+			p = *(*unsafe.Pointer)(p)
+		}
+		return p
+
+	case Slice:
+		return (*unsafeheader.Slice)(v.ptr).Data
+	}
+	panic(&ValueError{"reflect.Value.UnsafePointer", v.kind()})
+}
+
+// StringHeader is the runtime representation of a string.
+// It cannot be used safely or portably and its representation may
+// change in a later release.
+// Moreover, the Data field is not sufficient to guarantee the data
+// it references will not be garbage collected, so programs must keep
+// a separate, correctly typed pointer to the underlying data.
+type StringHeader struct {
+	Data uintptr
+	Len  int
+}
+
+// SliceHeader is the runtime representation of a slice.
+// It cannot be used safely or portably and its representation may
+// change in a later release.
+// Moreover, the Data field is not sufficient to guarantee the data
+// it references will not be garbage collected, so programs must keep
+// a separate, correctly typed pointer to the underlying data.
+type SliceHeader struct {
+	Data uintptr
+	Len  int
+	Cap  int
+}
+
+func typesMustMatch(what string, t1, t2 Type) {
+	if t1 != t2 {
+		panic(what + ": " + t1.String() + " != " + t2.String())
+	}
+}
+
+// arrayAt returns the i-th element of p,
+// an array whose elements are eltSize bytes wide.
+// The array pointed at by p must have at least i+1 elements:
+// it is invalid (but impossible to check here) to pass i >= len,
+// because then the result will point outside the array.
+// whySafe must explain why i < len. (Passing "i < len" is fine;
+// the benefit is to surface this assumption at the call site.)
+func arrayAt(p unsafe.Pointer, i int, eltSize uintptr, whySafe string) unsafe.Pointer {
+	return add(p, uintptr(i)*eltSize, "i < len")
+}
+
+// grow grows the slice s so that it can hold extra more values, allocating
+// more capacity if needed. It also returns the old and new slice lengths.
+func grow(s Value, extra int) (Value, int, int) {
+	i0 := s.Len()
+	i1 := i0 + extra
+	if i1 < i0 {
+		panic("reflect.Append: slice overflow")
+	}
+	m := s.Cap()
+	if i1 <= m {
+		return s.Slice(0, i1), i0, i1
+	}
+	if m == 0 {
+		m = extra
+	} else {
+		const threshold = 256
+		for m < i1 {
+			if i0 < threshold {
+				m += m
+			} else {
+				m += (m + 3*threshold) / 4
+			}
+		}
+	}
+	t := MakeSlice(s.Type(), i1, m)
+	Copy(t, s)
+	return t, i0, i1
+}
+
+// Append appends the values x to a slice s and returns the resulting slice.
+// As in Go, each x's value must be assignable to the slice's element type.
+func Append(s Value, x ...Value) Value {
+	s.mustBe(Slice)
+	s, i0, i1 := grow(s, len(x))
+	for i, j := i0, 0; i < i1; i, j = i+1, j+1 {
+		s.Index(i).Set(x[j])
+	}
+	return s
+}
+
+// AppendSlice appends a slice t to a slice s and returns the resulting slice.
+// The slices s and t must have the same element type.
+func AppendSlice(s, t Value) Value {
+	s.mustBe(Slice)
+	t.mustBe(Slice)
+	typesMustMatch("reflect.AppendSlice", s.Type().Elem(), t.Type().Elem())
+	s, i0, i1 := grow(s, t.Len())
+	Copy(s.Slice(i0, i1), t)
+	return s
+}
+
+// Copy copies the contents of src into dst until either
+// dst has been filled or src has been exhausted.
+// It returns the number of elements copied.
+// Dst and src each must have kind Slice or Array, and
+// dst and src must have the same element type.
+//
+// As a special case, src can have kind String if the element type of dst is kind Uint8.
+func Copy(dst, src Value) int {
+	dk := dst.kind()
+	if dk != Array && dk != Slice {
+		panic(&ValueError{"reflect.Copy", dk})
+	}
+	if dk == Array {
+		dst.mustBeAssignable()
+	}
+	dst.mustBeExported()
+
+	sk := src.kind()
+	var stringCopy bool
+	if sk != Array && sk != Slice {
+		stringCopy = sk == String && dst.typ.Elem().Kind() == Uint8
+		if !stringCopy {
+			panic(&ValueError{"reflect.Copy", sk})
+		}
+	}
+	src.mustBeExported()
+
+	de := dst.typ.Elem()
+	if !stringCopy {
+		se := src.typ.Elem()
+		typesMustMatch("reflect.Copy", de, se)
+	}
+
+	var ds, ss unsafeheader.Slice
+	if dk == Array {
+		ds.Data = dst.ptr
+		ds.Len = dst.Len()
+		ds.Cap = ds.Len
+	} else {
+		ds = *(*unsafeheader.Slice)(dst.ptr)
+	}
+	if sk == Array {
+		ss.Data = src.ptr
+		ss.Len = src.Len()
+		ss.Cap = ss.Len
+	} else if sk == Slice {
+		ss = *(*unsafeheader.Slice)(src.ptr)
+	} else {
+		sh := *(*unsafeheader.String)(src.ptr)
+		ss.Data = sh.Data
+		ss.Len = sh.Len
+		ss.Cap = sh.Len
+	}
+
+	return typedslicecopy(de.common(), ds, ss)
+}
+
+// A runtimeSelect is a single case passed to rselect.
+// This must match ../runtime/select.go:/runtimeSelect
+type runtimeSelect struct {
+	dir SelectDir      // SelectSend, SelectRecv or SelectDefault
+	typ *rtype         // channel type
+	ch  unsafe.Pointer // channel
+	val unsafe.Pointer // ptr to data (SendDir) or ptr to receive buffer (RecvDir)
+}
+
+// rselect runs a select. It returns the index of the chosen case.
+// If the case was a receive, val is filled in with the received value.
+// The conventional OK bool indicates whether the receive corresponds
+// to a sent value.
+//
+//go:noescape
+func rselect([]runtimeSelect) (chosen int, recvOK bool)
+
+// A SelectDir describes the communication direction of a select case.
+type SelectDir int
+
+// NOTE: These values must match ../runtime/select.go:/selectDir.
+
+const (
+	_             SelectDir = iota
+	SelectSend              // case Chan <- Send
+	SelectRecv              // case <-Chan:
+	SelectDefault           // default
+)
+
+// A SelectCase describes a single case in a select operation.
+// The kind of case depends on Dir, the communication direction.
+//
+// If Dir is SelectDefault, the case represents a default case.
+// Chan and Send must be zero Values.
+//
+// If Dir is SelectSend, the case represents a send operation.
+// Normally Chan's underlying value must be a channel, and Send's underlying value must be
+// assignable to the channel's element type. As a special case, if Chan is a zero Value,
+// then the case is ignored, and the field Send will also be ignored and may be either zero
+// or non-zero.
+//
+// If Dir is SelectRecv, the case represents a receive operation.
+// Normally Chan's underlying value must be a channel and Send must be a zero Value.
+// If Chan is a zero Value, then the case is ignored, but Send must still be a zero Value.
+// When a receive operation is selected, the received Value is returned by Select.
+type SelectCase struct {
+	Dir  SelectDir // direction of case
+	Chan Value     // channel to use (for send or receive)
+	Send Value     // value to send (for send)
+}
+
+// Select executes a select operation described by the list of cases.
+// Like the Go select statement, it blocks until at least one of the cases
+// can proceed, makes a uniform pseudo-random choice,
+// and then executes that case. It returns the index of the chosen case
+// and, if that case was a receive operation, the value received and a
+// boolean indicating whether the value corresponds to a send on the channel
+// (as opposed to a zero value received because the channel is closed).
+// Select supports a maximum of 65536 cases.
+func Select(cases []SelectCase) (chosen int, recv Value, recvOK bool) {
+	if len(cases) > 65536 {
+		panic("reflect.Select: too many cases (max 65536)")
+	}
+	// NOTE: Do not trust that caller is not modifying cases data underfoot.
+	// The range is safe because the caller cannot modify our copy of the len
+	// and each iteration makes its own copy of the value c.
+	var runcases []runtimeSelect
+	if len(cases) > 4 {
+		// Slice is heap allocated due to runtime dependent capacity.
+		runcases = make([]runtimeSelect, len(cases))
+	} else {
+		// Slice can be stack allocated due to constant capacity.
+		runcases = make([]runtimeSelect, len(cases), 4)
+	}
+
+	haveDefault := false
+	for i, c := range cases {
+		rc := &runcases[i]
+		rc.dir = c.Dir
+		switch c.Dir {
+		default:
+			panic("reflect.Select: invalid Dir")
+
+		case SelectDefault: // default
+			if haveDefault {
+				panic("reflect.Select: multiple default cases")
+			}
+			haveDefault = true
+			if c.Chan.IsValid() {
+				panic("reflect.Select: default case has Chan value")
+			}
+			if c.Send.IsValid() {
+				panic("reflect.Select: default case has Send value")
+			}
+
+		case SelectSend:
+			ch := c.Chan
+			if !ch.IsValid() {
+				break
+			}
+			ch.mustBe(Chan)
+			ch.mustBeExported()
+			tt := (*chanType)(unsafe.Pointer(ch.typ))
+			if ChanDir(tt.dir)&SendDir == 0 {
+				panic("reflect.Select: SendDir case using recv-only channel")
+			}
+			rc.ch = ch.pointer()
+			rc.typ = &tt.rtype
+			v := c.Send
+			if !v.IsValid() {
+				panic("reflect.Select: SendDir case missing Send value")
+			}
+			v.mustBeExported()
+			v = v.assignTo("reflect.Select", tt.elem, nil)
+			if v.flag&flagIndir != 0 {
+				rc.val = v.ptr
+			} else {
+				rc.val = unsafe.Pointer(&v.ptr)
+			}
+
+		case SelectRecv:
+			if c.Send.IsValid() {
+				panic("reflect.Select: RecvDir case has Send value")
+			}
+			ch := c.Chan
+			if !ch.IsValid() {
+				break
+			}
+			ch.mustBe(Chan)
+			ch.mustBeExported()
+			tt := (*chanType)(unsafe.Pointer(ch.typ))
+			if ChanDir(tt.dir)&RecvDir == 0 {
+				panic("reflect.Select: RecvDir case using send-only channel")
+			}
+			rc.ch = ch.pointer()
+			rc.typ = &tt.rtype
+			rc.val = unsafe_New(tt.elem)
+		}
+	}
+
+	chosen, recvOK = rselect(runcases)
+	if runcases[chosen].dir == SelectRecv {
+		tt := (*chanType)(unsafe.Pointer(runcases[chosen].typ))
+		t := tt.elem
+		p := runcases[chosen].val
+		fl := flag(t.Kind())
+		if ifaceIndir(t) {
+			recv = Value{t, p, fl | flagIndir}
+		} else {
+			recv = Value{t, *(*unsafe.Pointer)(p), fl}
+		}
+	}
+	return chosen, recv, recvOK
+}
+
+/*
+ * constructors
+ */
+
+// implemented in package runtime
+func unsafe_New(*rtype) unsafe.Pointer
+func unsafe_NewArray(*rtype, int) unsafe.Pointer
+
+// MakeSlice creates a new zero-initialized slice value
+// for the specified slice type, length, and capacity.
+func MakeSlice(typ Type, len, cap int) Value {
+	if typ.Kind() != Slice {
+		panic("reflect.MakeSlice of non-slice type")
+	}
+	if len < 0 {
+		panic("reflect.MakeSlice: negative len")
+	}
+	if cap < 0 {
+		panic("reflect.MakeSlice: negative cap")
+	}
+	if len > cap {
+		panic("reflect.MakeSlice: len > cap")
+	}
+
+	s := unsafeheader.Slice{Data: unsafe_NewArray(typ.Elem().(*rtype), cap), Len: len, Cap: cap}
+	return Value{typ.(*rtype), unsafe.Pointer(&s), flagIndir | flag(Slice)}
+}
+
+// MakeChan creates a new channel with the specified type and buffer size.
+func MakeChan(typ Type, buffer int) Value {
+	if typ.Kind() != Chan {
+		panic("reflect.MakeChan of non-chan type")
+	}
+	if buffer < 0 {
+		panic("reflect.MakeChan: negative buffer size")
+	}
+	if typ.ChanDir() != BothDir {
+		panic("reflect.MakeChan: unidirectional channel type")
+	}
+	t := typ.(*rtype)
+	ch := makechan(t, buffer)
+	return Value{t, ch, flag(Chan)}
+}
+
+// MakeMap creates a new map with the specified type.
+func MakeMap(typ Type) Value {
+	return MakeMapWithSize(typ, 0)
+}
+
+// MakeMapWithSize creates a new map with the specified type
+// and initial space for approximately n elements.
+func MakeMapWithSize(typ Type, n int) Value {
+	if typ.Kind() != Map {
+		panic("reflect.MakeMapWithSize of non-map type")
+	}
+	t := typ.(*rtype)
+	m := makemap(t, n)
+	return Value{t, m, flag(Map)}
+}
+
+// Indirect returns the value that v points to.
+// If v is a nil pointer, Indirect returns a zero Value.
+// If v is not a pointer, Indirect returns v.
+func Indirect(v Value) Value {
+	if v.Kind() != Pointer {
+		return v
+	}
+	return v.Elem()
+}
+
+// ValueOf returns a new Value initialized to the concrete value
+// stored in the interface i. ValueOf(nil) returns the zero Value.
+func ValueOf(i any) Value {
+	if i == nil {
+		return Value{}
+	}
+
+	// TODO: Maybe allow contents of a Value to live on the stack.
+	// For now we make the contents always escape to the heap. It
+	// makes life easier in a few places (see chanrecv/mapassign
+	// comment below).
+	escapes(i)
+
+	return unpackEface(i)
+}
+
+// Zero returns a Value representing the zero value for the specified type.
+// The result is different from the zero value of the Value struct,
+// which represents no value at all.
+// For example, Zero(TypeOf(42)) returns a Value with Kind Int and value 0.
+// The returned value is neither addressable nor settable.
+func Zero(typ Type) Value {
+	if typ == nil {
+		panic("reflect: Zero(nil)")
+	}
+	t := typ.(*rtype)
+	fl := flag(t.Kind())
+	if ifaceIndir(t) {
+		var p unsafe.Pointer
+		if t.size <= maxZero {
+			p = unsafe.Pointer(&zeroVal[0])
+		} else {
+			p = unsafe_New(t)
+		}
+		return Value{t, p, fl | flagIndir}
+	}
+	return Value{t, nil, fl}
+}
+
+// must match declarations in runtime/map.go.
+const maxZero = 1024
+
+//go:linkname zeroVal runtime.zeroVal
+var zeroVal [maxZero]byte
+
+// New returns a Value representing a pointer to a new zero value
+// for the specified type. That is, the returned Value's Type is PointerTo(typ).
+func New(typ Type) Value {
+	if typ == nil {
+		panic("reflect: New(nil)")
+	}
+	t := typ.(*rtype)
+	pt := t.ptrTo()
+	if ifaceIndir(pt) {
+		// This is a pointer to a go:notinheap type.
+		panic("reflect: New of type that may not be allocated in heap (possibly undefined cgo C type)")
+	}
+	ptr := unsafe_New(t)
+	fl := flag(Pointer)
+	return Value{pt, ptr, fl}
+}
+
+// NewAt returns a Value representing a pointer to a value of the
+// specified type, using p as that pointer.
+func NewAt(typ Type, p unsafe.Pointer) Value {
+	fl := flag(Pointer)
+	t := typ.(*rtype)
+	return Value{t.ptrTo(), p, fl}
+}
+
+// assignTo returns a value v that can be assigned directly to dst.
+// It panics if v is not assignable to dst.
+// For a conversion to an interface type, target, if not nil,
+// is a suggested scratch space to use.
+// target must be initialized memory (or nil).
+func (v Value) assignTo(context string, dst *rtype, target unsafe.Pointer) Value {
+	if v.flag&flagMethod != 0 {
+		v = makeMethodValue(context, v)
+	}
+
+	switch {
+	case directlyAssignable(dst, v.typ):
+		// Overwrite type so that they match.
+		// Same memory layout, so no harm done.
+		fl := v.flag&(flagAddr|flagIndir) | v.flag.ro()
+		fl |= flag(dst.Kind())
+		return Value{dst, v.ptr, fl}
+
+	case implements(dst, v.typ):
+		if v.Kind() == Interface && v.IsNil() {
+			// A nil ReadWriter passed to nil Reader is OK,
+			// but using ifaceE2I below will panic.
+			// Avoid the panic by returning a nil dst (e.g., Reader) explicitly.
+			return Value{dst, nil, flag(Interface)}
+		}
+		x := valueInterface(v, false)
+		if target == nil {
+			target = unsafe_New(dst)
+		}
+		if dst.NumMethod() == 0 {
+			*(*any)(target) = x
+		} else {
+			ifaceE2I(dst, x, target)
+		}
+		return Value{dst, target, flagIndir | flag(Interface)}
+	}
+
+	// Failed.
+	panic(context + ": value of type " + v.typ.String() + " is not assignable to type " + dst.String())
+}
+
+// Convert returns the value v converted to type t.
+// If the usual Go conversion rules do not allow conversion
+// of the value v to type t, or if converting v to type t panics, Convert panics.
+func (v Value) Convert(t Type) Value {
+	if v.flag&flagMethod != 0 {
+		v = makeMethodValue("Convert", v)
+	}
+	op := convertOp(t.common(), v.typ)
+	if op == nil {
+		panic("reflect.Value.Convert: value of type " + v.typ.String() + " cannot be converted to type " + t.String())
+	}
+	return op(v, t)
+}
+
+// CanConvert reports whether the value v can be converted to type t.
+// If v.CanConvert(t) returns true then v.Convert(t) will not panic.
+func (v Value) CanConvert(t Type) bool {
+	vt := v.Type()
+	if !vt.ConvertibleTo(t) {
+		return false
+	}
+	// Currently the only conversion that is OK in terms of type
+	// but that can panic depending on the value is converting
+	// from slice to pointer-to-array.
+	if vt.Kind() == Slice && t.Kind() == Pointer && t.Elem().Kind() == Array {
+		n := t.Elem().Len()
+		if n > v.Len() {
+			return false
+		}
+	}
+	return true
+}
+
+// convertOp returns the function to convert a value of type src
+// to a value of type dst. If the conversion is illegal, convertOp returns nil.
+func convertOp(dst, src *rtype) func(Value, Type) Value {
+	switch src.Kind() {
+	case Int, Int8, Int16, Int32, Int64:
+		switch dst.Kind() {
+		case Int, Int8, Int16, Int32, Int64, Uint, Uint8, Uint16, Uint32, Uint64, Uintptr:
+			return cvtInt
+		case Float32, Float64:
+			return cvtIntFloat
+		case String:
+			return cvtIntString
+		}
+
+	case Uint, Uint8, Uint16, Uint32, Uint64, Uintptr:
+		switch dst.Kind() {
+		case Int, Int8, Int16, Int32, Int64, Uint, Uint8, Uint16, Uint32, Uint64, Uintptr:
+			return cvtUint
+		case Float32, Float64:
+			return cvtUintFloat
+		case String:
+			return cvtUintString
+		}
+
+	case Float32, Float64:
+		switch dst.Kind() {
+		case Int, Int8, Int16, Int32, Int64:
+			return cvtFloatInt
+		case Uint, Uint8, Uint16, Uint32, Uint64, Uintptr:
+			return cvtFloatUint
+		case Float32, Float64:
+			return cvtFloat
+		}
+
+	case Complex64, Complex128:
+		switch dst.Kind() {
+		case Complex64, Complex128:
+			return cvtComplex
+		}
+
+	case String:
+		if dst.Kind() == Slice && dst.Elem().PkgPath() == "" {
+			switch dst.Elem().Kind() {
+			case Uint8:
+				return cvtStringBytes
+			case Int32:
+				return cvtStringRunes
+			}
+		}
+
+	case Slice:
+		if dst.Kind() == String && src.Elem().PkgPath() == "" {
+			switch src.Elem().Kind() {
+			case Uint8:
+				return cvtBytesString
+			case Int32:
+				return cvtRunesString
+			}
+		}
+		// "x is a slice, T is a pointer-to-array type,
+		// and the slice and array types have identical element types."
+		if dst.Kind() == Pointer && dst.Elem().Kind() == Array && src.Elem() == dst.Elem().Elem() {
+			return cvtSliceArrayPtr
+		}
+
+	case Chan:
+		if dst.Kind() == Chan && specialChannelAssignability(dst, src) {
+			return cvtDirect
+		}
+	}
+
+	// dst and src have same underlying type.
+	if haveIdenticalUnderlyingType(dst, src, false) {
+		return cvtDirect
+	}
+
+	// dst and src are non-defined pointer types with same underlying base type.
+	if dst.Kind() == Pointer && dst.Name() == "" &&
+		src.Kind() == Pointer && src.Name() == "" &&
+		haveIdenticalUnderlyingType(dst.Elem().common(), src.Elem().common(), false) {
+		return cvtDirect
+	}
+
+	if implements(dst, src) {
+		if src.Kind() == Interface {
+			return cvtI2I
+		}
+		return cvtT2I
+	}
+
+	return nil
+}
+
+// makeInt returns a Value of type t equal to bits (possibly truncated),
+// where t is a signed or unsigned int type.
+func makeInt(f flag, bits uint64, t Type) Value {
+	typ := t.common()
+	ptr := unsafe_New(typ)
+	switch typ.size {
+	case 1:
+		*(*uint8)(ptr) = uint8(bits)
+	case 2:
+		*(*uint16)(ptr) = uint16(bits)
+	case 4:
+		*(*uint32)(ptr) = uint32(bits)
+	case 8:
+		*(*uint64)(ptr) = bits
+	}
+	return Value{typ, ptr, f | flagIndir | flag(typ.Kind())}
+}
+
+// makeFloat returns a Value of type t equal to v (possibly truncated to float32),
+// where t is a float32 or float64 type.
+func makeFloat(f flag, v float64, t Type) Value {
+	typ := t.common()
+	ptr := unsafe_New(typ)
+	switch typ.size {
+	case 4:
+		*(*float32)(ptr) = float32(v)
+	case 8:
+		*(*float64)(ptr) = v
+	}
+	return Value{typ, ptr, f | flagIndir | flag(typ.Kind())}
+}
+
+// makeFloat returns a Value of type t equal to v, where t is a float32 type.
+func makeFloat32(f flag, v float32, t Type) Value {
+	typ := t.common()
+	ptr := unsafe_New(typ)
+	*(*float32)(ptr) = v
+	return Value{typ, ptr, f | flagIndir | flag(typ.Kind())}
+}
+
+// makeComplex returns a Value of type t equal to v (possibly truncated to complex64),
+// where t is a complex64 or complex128 type.
+func makeComplex(f flag, v complex128, t Type) Value {
+	typ := t.common()
+	ptr := unsafe_New(typ)
+	switch typ.size {
+	case 8:
+		*(*complex64)(ptr) = complex64(v)
+	case 16:
+		*(*complex128)(ptr) = v
+	}
+	return Value{typ, ptr, f | flagIndir | flag(typ.Kind())}
+}
+
+func makeString(f flag, v string, t Type) Value {
+	ret := New(t).Elem()
+	ret.SetString(v)
+	ret.flag = ret.flag&^flagAddr | f
+	return ret
+}
+
+func makeBytes(f flag, v []byte, t Type) Value {
+	ret := New(t).Elem()
+	ret.SetBytes(v)
+	ret.flag = ret.flag&^flagAddr | f
+	return ret
+}
+
+func makeRunes(f flag, v []rune, t Type) Value {
+	ret := New(t).Elem()
+	ret.setRunes(v)
+	ret.flag = ret.flag&^flagAddr | f
+	return ret
+}
+
+// These conversion functions are returned by convertOp
+// for classes of conversions. For example, the first function, cvtInt,
+// takes any value v of signed int type and returns the value converted
+// to type t, where t is any signed or unsigned int type.
+
+// convertOp: intXX -> [u]intXX
+func cvtInt(v Value, t Type) Value {
+	return makeInt(v.flag.ro(), uint64(v.Int()), t)
+}
+
+// convertOp: uintXX -> [u]intXX
+func cvtUint(v Value, t Type) Value {
+	return makeInt(v.flag.ro(), v.Uint(), t)
+}
+
+// convertOp: floatXX -> intXX
+func cvtFloatInt(v Value, t Type) Value {
+	return makeInt(v.flag.ro(), uint64(int64(v.Float())), t)
+}
+
+// convertOp: floatXX -> uintXX
+func cvtFloatUint(v Value, t Type) Value {
+	return makeInt(v.flag.ro(), uint64(v.Float()), t)
+}
+
+// convertOp: intXX -> floatXX
+func cvtIntFloat(v Value, t Type) Value {
+	return makeFloat(v.flag.ro(), float64(v.Int()), t)
+}
+
+// convertOp: uintXX -> floatXX
+func cvtUintFloat(v Value, t Type) Value {
+	return makeFloat(v.flag.ro(), float64(v.Uint()), t)
+}
+
+// convertOp: floatXX -> floatXX
+func cvtFloat(v Value, t Type) Value {
+	if v.Type().Kind() == Float32 && t.Kind() == Float32 {
+		// Don't do any conversion if both types have underlying type float32.
+		// This avoids converting to float64 and back, which will
+		// convert a signaling NaN to a quiet NaN. See issue 36400.
+		return makeFloat32(v.flag.ro(), *(*float32)(v.ptr), t)
+	}
+	return makeFloat(v.flag.ro(), v.Float(), t)
+}
+
+// convertOp: complexXX -> complexXX
+func cvtComplex(v Value, t Type) Value {
+	return makeComplex(v.flag.ro(), v.Complex(), t)
+}
+
+// convertOp: intXX -> string
+func cvtIntString(v Value, t Type) Value {
+	s := "\uFFFD"
+	if x := v.Int(); int64(rune(x)) == x {
+		s = string(rune(x))
+	}
+	return makeString(v.flag.ro(), s, t)
+}
+
+// convertOp: uintXX -> string
+func cvtUintString(v Value, t Type) Value {
+	s := "\uFFFD"
+	if x := v.Uint(); uint64(rune(x)) == x {
+		s = string(rune(x))
+	}
+	return makeString(v.flag.ro(), s, t)
+}
+
+// convertOp: []byte -> string
+func cvtBytesString(v Value, t Type) Value {
+	return makeString(v.flag.ro(), string(v.Bytes()), t)
+}
+
+// convertOp: string -> []byte
+func cvtStringBytes(v Value, t Type) Value {
+	return makeBytes(v.flag.ro(), []byte(v.String()), t)
+}
+
+// convertOp: []rune -> string
+func cvtRunesString(v Value, t Type) Value {
+	return makeString(v.flag.ro(), string(v.runes()), t)
+}
+
+// convertOp: string -> []rune
+func cvtStringRunes(v Value, t Type) Value {
+	return makeRunes(v.flag.ro(), []rune(v.String()), t)
+}
+
+// convertOp: []T -> *[N]T
+func cvtSliceArrayPtr(v Value, t Type) Value {
+	n := t.Elem().Len()
+	if n > v.Len() {
+		panic("reflect: cannot convert slice with length " + itoa.Itoa(v.Len()) + " to pointer to array with length " + itoa.Itoa(n))
+	}
+	h := (*unsafeheader.Slice)(v.ptr)
+	return Value{t.common(), h.Data, v.flag&^(flagIndir|flagAddr|flagKindMask) | flag(Pointer)}
+}
+
+// convertOp: direct copy
+func cvtDirect(v Value, typ Type) Value {
+	f := v.flag
+	t := typ.common()
+	ptr := v.ptr
+	if f&flagAddr != 0 {
+		// indirect, mutable word - make a copy
+		c := unsafe_New(t)
+		typedmemmove(t, c, ptr)
+		ptr = c
+		f &^= flagAddr
+	}
+	return Value{t, ptr, v.flag.ro() | f} // v.flag.ro()|f == f?
+}
+
+// convertOp: concrete -> interface
+func cvtT2I(v Value, typ Type) Value {
+	target := unsafe_New(typ.common())
+	x := valueInterface(v, false)
+	if typ.NumMethod() == 0 {
+		*(*any)(target) = x
+	} else {
+		ifaceE2I(typ.(*rtype), x, target)
+	}
+	return Value{typ.common(), target, v.flag.ro() | flagIndir | flag(Interface)}
+}
+
+// convertOp: interface -> interface
+func cvtI2I(v Value, typ Type) Value {
+	if v.IsNil() {
+		ret := Zero(typ)
+		ret.flag |= v.flag.ro()
+		return ret
+	}
+	return cvtT2I(v.Elem(), typ)
+}
+
+// implemented in ../runtime
+func chancap(ch unsafe.Pointer) int
+func chanclose(ch unsafe.Pointer)
+func chanlen(ch unsafe.Pointer) int
+
+// Note: some of the noescape annotations below are technically a lie,
+// but safe in the context of this package. Functions like chansend
+// and mapassign don't escape the referent, but may escape anything
+// the referent points to (they do shallow copies of the referent).
+// It is safe in this package because the referent may only point
+// to something a Value may point to, and that is always in the heap
+// (due to the escapes() call in ValueOf).
+
+//go:noescape
+func chanrecv(ch unsafe.Pointer, nb bool, val unsafe.Pointer) (selected, received bool)
+
+//go:noescape
+func chansend(ch unsafe.Pointer, val unsafe.Pointer, nb bool) bool
+
+func makechan(typ *rtype, size int) (ch unsafe.Pointer)
+func makemap(t *rtype, cap int) (m unsafe.Pointer)
+
+//go:noescape
+func mapaccess(t *rtype, m unsafe.Pointer, key unsafe.Pointer) (val unsafe.Pointer)
+
+//go:noescape
+func mapaccess_faststr(t *rtype, m unsafe.Pointer, key string) (val unsafe.Pointer)
+
+//go:noescape
+func mapassign(t *rtype, m unsafe.Pointer, key, val unsafe.Pointer)
+
+//go:noescape
+func mapassign_faststr(t *rtype, m unsafe.Pointer, key string, val unsafe.Pointer)
+
+//go:noescape
+func mapdelete(t *rtype, m unsafe.Pointer, key unsafe.Pointer)
+
+//go:noescape
+func mapdelete_faststr(t *rtype, m unsafe.Pointer, key string)
+
+//go:noescape
+func mapiterinit(t *rtype, m unsafe.Pointer, it *hiter)
+
+//go:noescape
+func mapiterkey(it *hiter) (key unsafe.Pointer)
+
+//go:noescape
+func mapiterelem(it *hiter) (elem unsafe.Pointer)
+
+//go:noescape
+func mapiternext(it *hiter)
+
+//go:noescape
+func maplen(m unsafe.Pointer) int
+
+// call calls fn with "stackArgsSize" bytes of stack arguments laid out
+// at stackArgs and register arguments laid out in regArgs. frameSize is
+// the total amount of stack space that will be reserved by call, so this
+// should include enough space to spill register arguments to the stack in
+// case of preemption.
+//
+// After fn returns, call copies stackArgsSize-stackRetOffset result bytes
+// back into stackArgs+stackRetOffset before returning, for any return
+// values passed on the stack. Register-based return values will be found
+// in the same regArgs structure.
+//
+// regArgs must also be prepared with an appropriate ReturnIsPtr bitmap
+// indicating which registers will contain pointer-valued return values. The
+// purpose of this bitmap is to keep pointers visible to the GC between
+// returning from reflectcall and actually using them.
+//
+// If copying result bytes back from the stack, the caller must pass the
+// argument frame type as stackArgsType, so that call can execute appropriate
+// write barriers during the copy.
+//
+// Arguments passed through to call do not escape. The type is used only in a
+// very limited callee of call, the stackArgs are copied, and regArgs is only
+// used in the call frame.
+//
+//go:noescape
+//go:linkname call runtime.reflectcall
+func call(stackArgsType *rtype, f, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+
+func ifaceE2I(t *rtype, src any, dst unsafe.Pointer)
+
+// memmove copies size bytes to dst from src. No write barriers are used.
+//
+//go:noescape
+func memmove(dst, src unsafe.Pointer, size uintptr)
+
+// typedmemmove copies a value of type t to dst from src.
+//
+//go:noescape
+func typedmemmove(t *rtype, dst, src unsafe.Pointer)
+
+// typedmemmovepartial is like typedmemmove but assumes that
+// dst and src point off bytes into the value and only copies size bytes.
+//
+//go:noescape
+func typedmemmovepartial(t *rtype, dst, src unsafe.Pointer, off, size uintptr)
+
+// typedmemclr zeros the value at ptr of type t.
+//
+//go:noescape
+func typedmemclr(t *rtype, ptr unsafe.Pointer)
+
+// typedmemclrpartial is like typedmemclr but assumes that
+// dst points off bytes into the value and only clears size bytes.
+//
+//go:noescape
+func typedmemclrpartial(t *rtype, ptr unsafe.Pointer, off, size uintptr)
+
+// typedslicecopy copies a slice of elemType values from src to dst,
+// returning the number of elements copied.
+//
+//go:noescape
+func typedslicecopy(elemType *rtype, dst, src unsafeheader.Slice) int
+
+//go:noescape
+func typehash(t *rtype, p unsafe.Pointer, h uintptr) uintptr
+
+func verifyNotInHeapPtr(p uintptr) bool
+
+// Dummy annotation marking that the value x escapes,
+// for use in cases where the reflect code is so clever that
+// the compiler cannot follow.
+func escapes(x any) {
+	if dummy.b {
+		dummy.x = x
+	}
+}
+
+var dummy struct {
+	b bool
+	x any
+}
diff --git a/contrib/go/_std_1.18/src/reflect/visiblefields.go b/contrib/go/_std_1.19/src/reflect/visiblefields.go
index 9375faa110..9375faa110 100644
--- a/contrib/go/_std_1.18/src/reflect/visiblefields.go
+++ b/contrib/go/_std_1.19/src/reflect/visiblefields.go
diff --git a/contrib/go/_std_1.19/src/runtime/alg.go b/contrib/go/_std_1.19/src/runtime/alg.go
new file mode 100644
index 0000000000..2a413eeef3
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/alg.go
@@ -0,0 +1,353 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"internal/cpu"
+	"internal/goarch"
+	"unsafe"
+)
+
+const (
+	c0 = uintptr((8-goarch.PtrSize)/4*2860486313 + (goarch.PtrSize-4)/4*33054211828000289)
+	c1 = uintptr((8-goarch.PtrSize)/4*3267000013 + (goarch.PtrSize-4)/4*23344194077549503)
+)
+
+func memhash0(p unsafe.Pointer, h uintptr) uintptr {
+	return h
+}
+
+func memhash8(p unsafe.Pointer, h uintptr) uintptr {
+	return memhash(p, h, 1)
+}
+
+func memhash16(p unsafe.Pointer, h uintptr) uintptr {
+	return memhash(p, h, 2)
+}
+
+func memhash128(p unsafe.Pointer, h uintptr) uintptr {
+	return memhash(p, h, 16)
+}
+
+//go:nosplit
+func memhash_varlen(p unsafe.Pointer, h uintptr) uintptr {
+	ptr := getclosureptr()
+	size := *(*uintptr)(unsafe.Pointer(ptr + unsafe.Sizeof(h)))
+	return memhash(p, h, size)
+}
+
+// runtime variable to check if the processor we're running on
+// actually supports the instructions used by the AES-based
+// hash implementation.
+var useAeshash bool
+
+// in asm_*.s
+func memhash(p unsafe.Pointer, h, s uintptr) uintptr
+func memhash32(p unsafe.Pointer, h uintptr) uintptr
+func memhash64(p unsafe.Pointer, h uintptr) uintptr
+func strhash(p unsafe.Pointer, h uintptr) uintptr
+
+func strhashFallback(a unsafe.Pointer, h uintptr) uintptr {
+	x := (*stringStruct)(a)
+	return memhashFallback(x.str, h, uintptr(x.len))
+}
+
+// NOTE: Because NaN != NaN, a map can contain any
+// number of (mostly useless) entries keyed with NaNs.
+// To avoid long hash chains, we assign a random number
+// as the hash value for a NaN.
+
+func f32hash(p unsafe.Pointer, h uintptr) uintptr {
+	f := *(*float32)(p)
+	switch {
+	case f == 0:
+		return c1 * (c0 ^ h) // +0, -0
+	case f != f:
+		return c1 * (c0 ^ h ^ uintptr(fastrand())) // any kind of NaN
+	default:
+		return memhash(p, h, 4)
+	}
+}
+
+func f64hash(p unsafe.Pointer, h uintptr) uintptr {
+	f := *(*float64)(p)
+	switch {
+	case f == 0:
+		return c1 * (c0 ^ h) // +0, -0
+	case f != f:
+		return c1 * (c0 ^ h ^ uintptr(fastrand())) // any kind of NaN
+	default:
+		return memhash(p, h, 8)
+	}
+}
+
+func c64hash(p unsafe.Pointer, h uintptr) uintptr {
+	x := (*[2]float32)(p)
+	return f32hash(unsafe.Pointer(&x[1]), f32hash(unsafe.Pointer(&x[0]), h))
+}
+
+func c128hash(p unsafe.Pointer, h uintptr) uintptr {
+	x := (*[2]float64)(p)
+	return f64hash(unsafe.Pointer(&x[1]), f64hash(unsafe.Pointer(&x[0]), h))
+}
+
+func interhash(p unsafe.Pointer, h uintptr) uintptr {
+	a := (*iface)(p)
+	tab := a.tab
+	if tab == nil {
+		return h
+	}
+	t := tab._type
+	if t.equal == nil {
+		// Check hashability here. We could do this check inside
+		// typehash, but we want to report the topmost type in
+		// the error text (e.g. in a struct with a field of slice type
+		// we want to report the struct, not the slice).
+		panic(errorString("hash of unhashable type " + t.string()))
+	}
+	if isDirectIface(t) {
+		return c1 * typehash(t, unsafe.Pointer(&a.data), h^c0)
+	} else {
+		return c1 * typehash(t, a.data, h^c0)
+	}
+}
+
+func nilinterhash(p unsafe.Pointer, h uintptr) uintptr {
+	a := (*eface)(p)
+	t := a._type
+	if t == nil {
+		return h
+	}
+	if t.equal == nil {
+		// See comment in interhash above.
+		panic(errorString("hash of unhashable type " + t.string()))
+	}
+	if isDirectIface(t) {
+		return c1 * typehash(t, unsafe.Pointer(&a.data), h^c0)
+	} else {
+		return c1 * typehash(t, a.data, h^c0)
+	}
+}
+
+// typehash computes the hash of the object of type t at address p.
+// h is the seed.
+// This function is seldom used. Most maps use for hashing either
+// fixed functions (e.g. f32hash) or compiler-generated functions
+// (e.g. for a type like struct { x, y string }). This implementation
+// is slower but more general and is used for hashing interface types
+// (called from interhash or nilinterhash, above) or for hashing in
+// maps generated by reflect.MapOf (reflect_typehash, below).
+// Note: this function must match the compiler generated
+// functions exactly. See issue 37716.
+func typehash(t *_type, p unsafe.Pointer, h uintptr) uintptr {
+	if t.tflag&tflagRegularMemory != 0 {
+		// Handle ptr sizes specially, see issue 37086.
+		switch t.size {
+		case 4:
+			return memhash32(p, h)
+		case 8:
+			return memhash64(p, h)
+		default:
+			return memhash(p, h, t.size)
+		}
+	}
+	switch t.kind & kindMask {
+	case kindFloat32:
+		return f32hash(p, h)
+	case kindFloat64:
+		return f64hash(p, h)
+	case kindComplex64:
+		return c64hash(p, h)
+	case kindComplex128:
+		return c128hash(p, h)
+	case kindString:
+		return strhash(p, h)
+	case kindInterface:
+		i := (*interfacetype)(unsafe.Pointer(t))
+		if len(i.mhdr) == 0 {
+			return nilinterhash(p, h)
+		}
+		return interhash(p, h)
+	case kindArray:
+		a := (*arraytype)(unsafe.Pointer(t))
+		for i := uintptr(0); i < a.len; i++ {
+			h = typehash(a.elem, add(p, i*a.elem.size), h)
+		}
+		return h
+	case kindStruct:
+		s := (*structtype)(unsafe.Pointer(t))
+		for _, f := range s.fields {
+			if f.name.isBlank() {
+				continue
+			}
+			h = typehash(f.typ, add(p, f.offset), h)
+		}
+		return h
+	default:
+		// Should never happen, as typehash should only be called
+		// with comparable types.
+		panic(errorString("hash of unhashable type " + t.string()))
+	}
+}
+
+//go:linkname reflect_typehash reflect.typehash
+func reflect_typehash(t *_type, p unsafe.Pointer, h uintptr) uintptr {
+	return typehash(t, p, h)
+}
+
+func memequal0(p, q unsafe.Pointer) bool {
+	return true
+}
+func memequal8(p, q unsafe.Pointer) bool {
+	return *(*int8)(p) == *(*int8)(q)
+}
+func memequal16(p, q unsafe.Pointer) bool {
+	return *(*int16)(p) == *(*int16)(q)
+}
+func memequal32(p, q unsafe.Pointer) bool {
+	return *(*int32)(p) == *(*int32)(q)
+}
+func memequal64(p, q unsafe.Pointer) bool {
+	return *(*int64)(p) == *(*int64)(q)
+}
+func memequal128(p, q unsafe.Pointer) bool {
+	return *(*[2]int64)(p) == *(*[2]int64)(q)
+}
+func f32equal(p, q unsafe.Pointer) bool {
+	return *(*float32)(p) == *(*float32)(q)
+}
+func f64equal(p, q unsafe.Pointer) bool {
+	return *(*float64)(p) == *(*float64)(q)
+}
+func c64equal(p, q unsafe.Pointer) bool {
+	return *(*complex64)(p) == *(*complex64)(q)
+}
+func c128equal(p, q unsafe.Pointer) bool {
+	return *(*complex128)(p) == *(*complex128)(q)
+}
+func strequal(p, q unsafe.Pointer) bool {
+	return *(*string)(p) == *(*string)(q)
+}
+func interequal(p, q unsafe.Pointer) bool {
+	x := *(*iface)(p)
+	y := *(*iface)(q)
+	return x.tab == y.tab && ifaceeq(x.tab, x.data, y.data)
+}
+func nilinterequal(p, q unsafe.Pointer) bool {
+	x := *(*eface)(p)
+	y := *(*eface)(q)
+	return x._type == y._type && efaceeq(x._type, x.data, y.data)
+}
+func efaceeq(t *_type, x, y unsafe.Pointer) bool {
+	if t == nil {
+		return true
+	}
+	eq := t.equal
+	if eq == nil {
+		panic(errorString("comparing uncomparable type " + t.string()))
+	}
+	if isDirectIface(t) {
+		// Direct interface types are ptr, chan, map, func, and single-element structs/arrays thereof.
+		// Maps and funcs are not comparable, so they can't reach here.
+		// Ptrs, chans, and single-element items can be compared directly using ==.
+		return x == y
+	}
+	return eq(x, y)
+}
+func ifaceeq(tab *itab, x, y unsafe.Pointer) bool {
+	if tab == nil {
+		return true
+	}
+	t := tab._type
+	eq := t.equal
+	if eq == nil {
+		panic(errorString("comparing uncomparable type " + t.string()))
+	}
+	if isDirectIface(t) {
+		// See comment in efaceeq.
+		return x == y
+	}
+	return eq(x, y)
+}
+
+// Testing adapters for hash quality tests (see hash_test.go)
+func stringHash(s string, seed uintptr) uintptr {
+	return strhash(noescape(unsafe.Pointer(&s)), seed)
+}
+
+func bytesHash(b []byte, seed uintptr) uintptr {
+	s := (*slice)(unsafe.Pointer(&b))
+	return memhash(s.array, seed, uintptr(s.len))
+}
+
+func int32Hash(i uint32, seed uintptr) uintptr {
+	return memhash32(noescape(unsafe.Pointer(&i)), seed)
+}
+
+func int64Hash(i uint64, seed uintptr) uintptr {
+	return memhash64(noescape(unsafe.Pointer(&i)), seed)
+}
+
+func efaceHash(i any, seed uintptr) uintptr {
+	return nilinterhash(noescape(unsafe.Pointer(&i)), seed)
+}
+
+func ifaceHash(i interface {
+	F()
+}, seed uintptr) uintptr {
+	return interhash(noescape(unsafe.Pointer(&i)), seed)
+}
+
+const hashRandomBytes = goarch.PtrSize / 4 * 64
+
+// used in asm_{386,amd64,arm64}.s to seed the hash function
+var aeskeysched [hashRandomBytes]byte
+
+// used in hash{32,64}.go to seed the hash function
+var hashkey [4]uintptr
+
+func alginit() {
+	// Install AES hash algorithms if the instructions needed are present.
+	if (GOARCH == "386" || GOARCH == "amd64") &&
+		cpu.X86.HasAES && // AESENC
+		cpu.X86.HasSSSE3 && // PSHUFB
+		cpu.X86.HasSSE41 { // PINSR{D,Q}
+		initAlgAES()
+		return
+	}
+	if GOARCH == "arm64" && cpu.ARM64.HasAES {
+		initAlgAES()
+		return
+	}
+	getRandomData((*[len(hashkey) * goarch.PtrSize]byte)(unsafe.Pointer(&hashkey))[:])
+	hashkey[0] |= 1 // make sure these numbers are odd
+	hashkey[1] |= 1
+	hashkey[2] |= 1
+	hashkey[3] |= 1
+}
+
+func initAlgAES() {
+	useAeshash = true
+	// Initialize with random data so hash collisions will be hard to engineer.
+	getRandomData(aeskeysched[:])
+}
+
+// Note: These routines perform the read with a native endianness.
+func readUnaligned32(p unsafe.Pointer) uint32 {
+	q := (*[4]byte)(p)
+	if goarch.BigEndian {
+		return uint32(q[3]) | uint32(q[2])<<8 | uint32(q[1])<<16 | uint32(q[0])<<24
+	}
+	return uint32(q[0]) | uint32(q[1])<<8 | uint32(q[2])<<16 | uint32(q[3])<<24
+}
+
+func readUnaligned64(p unsafe.Pointer) uint64 {
+	q := (*[8]byte)(p)
+	if goarch.BigEndian {
+		return uint64(q[7]) | uint64(q[6])<<8 | uint64(q[5])<<16 | uint64(q[4])<<24 |
+			uint64(q[3])<<32 | uint64(q[2])<<40 | uint64(q[1])<<48 | uint64(q[0])<<56
+	}
+	return uint64(q[0]) | uint64(q[1])<<8 | uint64(q[2])<<16 | uint64(q[3])<<24 | uint64(q[4])<<32 | uint64(q[5])<<40 | uint64(q[6])<<48 | uint64(q[7])<<56
+}
diff --git a/contrib/go/_std_1.19/src/runtime/asan0.go b/contrib/go/_std_1.19/src/runtime/asan0.go
new file mode 100644
index 0000000000..0948786200
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/asan0.go
@@ -0,0 +1,23 @@
+// Copyright 2021 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !asan
+
+// Dummy ASan support API, used when not built with -asan.
+
+package runtime
+
+import (
+	"unsafe"
+)
+
+const asanenabled = false
+
+// Because asanenabled is false, none of these functions should be called.
+
+func asanread(addr unsafe.Pointer, sz uintptr)            { throw("asan") }
+func asanwrite(addr unsafe.Pointer, sz uintptr)           { throw("asan") }
+func asanunpoison(addr unsafe.Pointer, sz uintptr)        { throw("asan") }
+func asanpoison(addr unsafe.Pointer, sz uintptr)          { throw("asan") }
+func asanregisterglobals(addr unsafe.Pointer, sz uintptr) { throw("asan") }
diff --git a/contrib/go/_std_1.18/src/runtime/asm.s b/contrib/go/_std_1.19/src/runtime/asm.s
index 84d56de7dd..84d56de7dd 100644
--- a/contrib/go/_std_1.18/src/runtime/asm.s
+++ b/contrib/go/_std_1.19/src/runtime/asm.s
diff --git a/contrib/go/_std_1.19/src/runtime/asm_amd64.h b/contrib/go/_std_1.19/src/runtime/asm_amd64.h
new file mode 100644
index 0000000000..49e0ee2323
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/asm_amd64.h
@@ -0,0 +1,14 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Define features that are guaranteed to be supported by setting the AMD64 variable.
+// If a feature is supported, there's no need to check it at runtime every time.
+
+#ifdef GOAMD64_v3
+#define hasAVX2
+#endif
+
+#ifdef GOAMD64_v4
+#define hasAVX2
+#endif
diff --git a/contrib/go/_std_1.19/src/runtime/asm_amd64.s b/contrib/go/_std_1.19/src/runtime/asm_amd64.s
new file mode 100644
index 0000000000..d2f7984178
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/asm_amd64.s
@@ -0,0 +1,2059 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "go_asm.h"
+#include "go_tls.h"
+#include "funcdata.h"
+#include "textflag.h"
+#include "cgo/abi_amd64.h"
+
+// _rt0_amd64 is common startup code for most amd64 systems when using
+// internal linking. This is the entry point for the program from the
+// kernel for an ordinary -buildmode=exe program. The stack holds the
+// number of arguments and the C-style argv.
+TEXT _rt0_amd64(SB),NOSPLIT,$-8
+	MOVQ	0(SP), DI	// argc
+	LEAQ	8(SP), SI	// argv
+	JMP	runtime·rt0_go(SB)
+
+// main is common startup code for most amd64 systems when using
+// external linking. The C startup code will call the symbol "main"
+// passing argc and argv in the usual C ABI registers DI and SI.
+TEXT main(SB),NOSPLIT,$-8
+	JMP	runtime·rt0_go(SB)
+
+// _rt0_amd64_lib is common startup code for most amd64 systems when
+// using -buildmode=c-archive or -buildmode=c-shared. The linker will
+// arrange to invoke this function as a global constructor (for
+// c-archive) or when the shared library is loaded (for c-shared).
+// We expect argc and argv to be passed in the usual C ABI registers
+// DI and SI.
+TEXT _rt0_amd64_lib(SB),NOSPLIT,$0
+	// Transition from C ABI to Go ABI.
+	PUSH_REGS_HOST_TO_ABI0()
+
+	MOVQ	DI, _rt0_amd64_lib_argc<>(SB)
+	MOVQ	SI, _rt0_amd64_lib_argv<>(SB)
+
+	// Synchronous initialization.
+	CALL	runtime·libpreinit(SB)
+
+	// Create a new thread to finish Go runtime initialization.
+	MOVQ	_cgo_sys_thread_create(SB), AX
+	TESTQ	AX, AX
+	JZ	nocgo
+
+	// We're calling back to C.
+	// Align stack per ELF ABI requirements.
+	MOVQ	SP, BX  // Callee-save in C ABI
+	ANDQ	$~15, SP
+	MOVQ	$_rt0_amd64_lib_go(SB), DI
+	MOVQ	$0, SI
+	CALL	AX
+	MOVQ	BX, SP
+	JMP	restore
+
+nocgo:
+	ADJSP	$16
+	MOVQ	$0x800000, 0(SP)		// stacksize
+	MOVQ	$_rt0_amd64_lib_go(SB), AX
+	MOVQ	AX, 8(SP)			// fn
+	CALL	runtime·newosproc0(SB)
+	ADJSP	$-16
+
+restore:
+	POP_REGS_HOST_TO_ABI0()
+	RET
+
+// _rt0_amd64_lib_go initializes the Go runtime.
+// This is started in a separate thread by _rt0_amd64_lib.
+TEXT _rt0_amd64_lib_go(SB),NOSPLIT,$0
+	MOVQ	_rt0_amd64_lib_argc<>(SB), DI
+	MOVQ	_rt0_amd64_lib_argv<>(SB), SI
+	JMP	runtime·rt0_go(SB)
+
+DATA _rt0_amd64_lib_argc<>(SB)/8, $0
+GLOBL _rt0_amd64_lib_argc<>(SB),NOPTR, $8
+DATA _rt0_amd64_lib_argv<>(SB)/8, $0
+GLOBL _rt0_amd64_lib_argv<>(SB),NOPTR, $8
+
+#ifdef GOAMD64_v2
+DATA bad_cpu_msg<>+0x00(SB)/84, $"This program can only be run on AMD64 processors with v2 microarchitecture support.\n"
+#endif
+
+#ifdef GOAMD64_v3
+DATA bad_cpu_msg<>+0x00(SB)/84, $"This program can only be run on AMD64 processors with v3 microarchitecture support.\n"
+#endif
+
+#ifdef GOAMD64_v4
+DATA bad_cpu_msg<>+0x00(SB)/84, $"This program can only be run on AMD64 processors with v4 microarchitecture support.\n"
+#endif
+
+GLOBL bad_cpu_msg<>(SB), RODATA, $84
+
+// Define a list of AMD64 microarchitecture level features
+// https://en.wikipedia.org/wiki/X86-64#Microarchitecture_levels
+
+                     // SSE3     SSSE3    CMPXCHNG16 SSE4.1    SSE4.2    POPCNT
+#define V2_FEATURES_CX (1 << 0 | 1 << 9 | 1 << 13  | 1 << 19 | 1 << 20 | 1 << 23)
+                         // LAHF/SAHF
+#define V2_EXT_FEATURES_CX (1 << 0)
+                                      // FMA       MOVBE     OSXSAVE   AVX       F16C
+#define V3_FEATURES_CX (V2_FEATURES_CX | 1 << 12 | 1 << 22 | 1 << 27 | 1 << 28 | 1 << 29)
+                                              // ABM (FOR LZNCT)
+#define V3_EXT_FEATURES_CX (V2_EXT_FEATURES_CX | 1 << 5)
+                         // BMI1     AVX2     BMI2
+#define V3_EXT_FEATURES_BX (1 << 3 | 1 << 5 | 1 << 8)
+                       // XMM      YMM
+#define V3_OS_SUPPORT_AX (1 << 1 | 1 << 2)
+
+#define V4_FEATURES_CX V3_FEATURES_CX
+
+#define V4_EXT_FEATURES_CX V3_EXT_FEATURES_CX
+                                              // AVX512F   AVX512DQ  AVX512CD  AVX512BW  AVX512VL
+#define V4_EXT_FEATURES_BX (V3_EXT_FEATURES_BX | 1 << 16 | 1 << 17 | 1 << 28 | 1 << 30 | 1 << 31)
+                                          // OPMASK   ZMM
+#define V4_OS_SUPPORT_AX (V3_OS_SUPPORT_AX | 1 << 5 | (1 << 6 | 1 << 7))
+
+#ifdef GOAMD64_v2
+#define NEED_MAX_CPUID 0x80000001
+#define NEED_FEATURES_CX V2_FEATURES_CX
+#define NEED_EXT_FEATURES_CX V2_EXT_FEATURES_CX
+#endif
+
+#ifdef GOAMD64_v3
+#define NEED_MAX_CPUID 0x80000001
+#define NEED_FEATURES_CX V3_FEATURES_CX
+#define NEED_EXT_FEATURES_CX V3_EXT_FEATURES_CX
+#define NEED_EXT_FEATURES_BX V3_EXT_FEATURES_BX
+#define NEED_OS_SUPPORT_AX V3_OS_SUPPORT_AX
+#endif
+
+#ifdef GOAMD64_v4
+#define NEED_MAX_CPUID 0x80000001
+#define NEED_FEATURES_CX V4_FEATURES_CX
+#define NEED_EXT_FEATURES_CX V4_EXT_FEATURES_CX
+#define NEED_EXT_FEATURES_BX V4_EXT_FEATURES_BX
+
+// Darwin requires a different approach to check AVX512 support, see CL 285572.
+#ifdef GOOS_darwin
+#define NEED_OS_SUPPORT_AX V3_OS_SUPPORT_AX
+// These values are from:
+// https://github.com/apple/darwin-xnu/blob/xnu-4570.1.46/osfmk/i386/cpu_capabilities.h
+#define commpage64_base_address         0x00007fffffe00000
+#define commpage64_cpu_capabilities64   (commpage64_base_address+0x010)
+#define commpage64_version              (commpage64_base_address+0x01E)
+#define hasAVX512F                      0x0000004000000000
+#define hasAVX512CD                     0x0000008000000000
+#define hasAVX512DQ                     0x0000010000000000
+#define hasAVX512BW                     0x0000020000000000
+#define hasAVX512VL                     0x0000100000000000
+#define NEED_DARWIN_SUPPORT             (hasAVX512F | hasAVX512DQ | hasAVX512CD | hasAVX512BW | hasAVX512VL)
+#else
+#define NEED_OS_SUPPORT_AX V4_OS_SUPPORT_AX
+#endif
+
+#endif
+
+TEXT runtime·rt0_go(SB),NOSPLIT|TOPFRAME,$0
+	// copy arguments forward on an even stack
+	MOVQ	DI, AX		// argc
+	MOVQ	SI, BX		// argv
+	SUBQ	$(5*8), SP		// 3args 2auto
+	ANDQ	$~15, SP
+	MOVQ	AX, 24(SP)
+	MOVQ	BX, 32(SP)
+
+	// create istack out of the given (operating system) stack.
+	// _cgo_init may update stackguard.
+	MOVQ	$runtime·g0(SB), DI
+	LEAQ	(-64*1024+104)(SP), BX
+	MOVQ	BX, g_stackguard0(DI)
+	MOVQ	BX, g_stackguard1(DI)
+	MOVQ	BX, (g_stack+stack_lo)(DI)
+	MOVQ	SP, (g_stack+stack_hi)(DI)
+
+	// find out information about the processor we're on
+	MOVL	$0, AX
+	CPUID
+	CMPL	AX, $0
+	JE	nocpuinfo
+
+	CMPL	BX, $0x756E6547  // "Genu"
+	JNE	notintel
+	CMPL	DX, $0x49656E69  // "ineI"
+	JNE	notintel
+	CMPL	CX, $0x6C65746E  // "ntel"
+	JNE	notintel
+	MOVB	$1, runtime·isIntel(SB)
+
+notintel:
+	// Load EAX=1 cpuid flags
+	MOVL	$1, AX
+	CPUID
+	MOVL	AX, runtime·processorVersionInfo(SB)
+
+nocpuinfo:
+	// if there is an _cgo_init, call it.
+	MOVQ	_cgo_init(SB), AX
+	TESTQ	AX, AX
+	JZ	needtls
+	// arg 1: g0, already in DI
+	MOVQ	$setg_gcc<>(SB), SI // arg 2: setg_gcc
+#ifdef GOOS_android
+	MOVQ	$runtime·tls_g(SB), DX 	// arg 3: &tls_g
+	// arg 4: TLS base, stored in slot 0 (Android's TLS_SLOT_SELF).
+	// Compensate for tls_g (+16).
+	MOVQ	-16(TLS), CX
+#else
+	MOVQ	$0, DX	// arg 3, 4: not used when using platform's TLS
+	MOVQ	$0, CX
+#endif
+#ifdef GOOS_windows
+	// Adjust for the Win64 calling convention.
+	MOVQ	CX, R9 // arg 4
+	MOVQ	DX, R8 // arg 3
+	MOVQ	SI, DX // arg 2
+	MOVQ	DI, CX // arg 1
+#endif
+	CALL	AX
+
+	// update stackguard after _cgo_init
+	MOVQ	$runtime·g0(SB), CX
+	MOVQ	(g_stack+stack_lo)(CX), AX
+	ADDQ	$const__StackGuard, AX
+	MOVQ	AX, g_stackguard0(CX)
+	MOVQ	AX, g_stackguard1(CX)
+
+#ifndef GOOS_windows
+	JMP ok
+#endif
+needtls:
+#ifdef GOOS_plan9
+	// skip TLS setup on Plan 9
+	JMP ok
+#endif
+#ifdef GOOS_solaris
+	// skip TLS setup on Solaris
+	JMP ok
+#endif
+#ifdef GOOS_illumos
+	// skip TLS setup on illumos
+	JMP ok
+#endif
+#ifdef GOOS_darwin
+	// skip TLS setup on Darwin
+	JMP ok
+#endif
+#ifdef GOOS_openbsd
+	// skip TLS setup on OpenBSD
+	JMP ok
+#endif
+
+	LEAQ	runtime·m0+m_tls(SB), DI
+	CALL	runtime·settls(SB)
+
+	// store through it, to make sure it works
+	get_tls(BX)
+	MOVQ	$0x123, g(BX)
+	MOVQ	runtime·m0+m_tls(SB), AX
+	CMPQ	AX, $0x123
+	JEQ 2(PC)
+	CALL	runtime·abort(SB)
+ok:
+	// set the per-goroutine and per-mach "registers"
+	get_tls(BX)
+	LEAQ	runtime·g0(SB), CX
+	MOVQ	CX, g(BX)
+	LEAQ	runtime·m0(SB), AX
+
+	// save m->g0 = g0
+	MOVQ	CX, m_g0(AX)
+	// save m0 to g0->m
+	MOVQ	AX, g_m(CX)
+
+	CLD				// convention is D is always left cleared
+
+	// Check GOAMD64 reqirements
+	// We need to do this after setting up TLS, so that
+	// we can report an error if there is a failure. See issue 49586.
+#ifdef NEED_FEATURES_CX
+	MOVL	$0, AX
+	CPUID
+	CMPL	AX, $0
+	JE	bad_cpu
+	MOVL	$1, AX
+	CPUID
+	ANDL	$NEED_FEATURES_CX, CX
+	CMPL	CX, $NEED_FEATURES_CX
+	JNE	bad_cpu
+#endif
+
+#ifdef NEED_MAX_CPUID
+	MOVL	$0x80000000, AX
+	CPUID
+	CMPL	AX, $NEED_MAX_CPUID
+	JL	bad_cpu
+#endif
+
+#ifdef NEED_EXT_FEATURES_BX
+	MOVL	$7, AX
+	MOVL	$0, CX
+	CPUID
+	ANDL	$NEED_EXT_FEATURES_BX, BX
+	CMPL	BX, $NEED_EXT_FEATURES_BX
+	JNE	bad_cpu
+#endif
+
+#ifdef NEED_EXT_FEATURES_CX
+	MOVL	$0x80000001, AX
+	CPUID
+	ANDL	$NEED_EXT_FEATURES_CX, CX
+	CMPL	CX, $NEED_EXT_FEATURES_CX
+	JNE	bad_cpu
+#endif
+
+#ifdef NEED_OS_SUPPORT_AX
+	XORL    CX, CX
+	XGETBV
+	ANDL	$NEED_OS_SUPPORT_AX, AX
+	CMPL	AX, $NEED_OS_SUPPORT_AX
+	JNE	bad_cpu
+#endif
+
+#ifdef NEED_DARWIN_SUPPORT
+	MOVQ	$commpage64_version, BX
+	CMPW	(BX), $13  // cpu_capabilities64 undefined in versions < 13
+	JL	bad_cpu
+	MOVQ	$commpage64_cpu_capabilities64, BX
+	MOVQ	(BX), BX
+	MOVQ	$NEED_DARWIN_SUPPORT, CX
+	ANDQ	CX, BX
+	CMPQ	BX, CX
+	JNE	bad_cpu
+#endif
+
+	CALL	runtime·check(SB)
+
+	MOVL	24(SP), AX		// copy argc
+	MOVL	AX, 0(SP)
+	MOVQ	32(SP), AX		// copy argv
+	MOVQ	AX, 8(SP)
+	CALL	runtime·args(SB)
+	CALL	runtime·osinit(SB)
+	CALL	runtime·schedinit(SB)
+
+	// create a new goroutine to start program
+	MOVQ	$runtime·mainPC(SB), AX		// entry
+	PUSHQ	AX
+	CALL	runtime·newproc(SB)
+	POPQ	AX
+
+	// start this M
+	CALL	runtime·mstart(SB)
+
+	CALL	runtime·abort(SB)	// mstart should never return
+	RET
+
+bad_cpu: // show that the program requires a certain microarchitecture level.
+	MOVQ	$2, 0(SP)
+	MOVQ	$bad_cpu_msg<>(SB), AX
+	MOVQ	AX, 8(SP)
+	MOVQ	$84, 16(SP)
+	CALL	runtime·write(SB)
+	MOVQ	$1, 0(SP)
+	CALL	runtime·exit(SB)
+	CALL	runtime·abort(SB)
+	RET
+
+	// Prevent dead-code elimination of debugCallV2, which is
+	// intended to be called by debuggers.
+	MOVQ	$runtime·debugCallV2<ABIInternal>(SB), AX
+	RET
+
+// mainPC is a function value for runtime.main, to be passed to newproc.
+// The reference to runtime.main is made via ABIInternal, since the
+// actual function (not the ABI0 wrapper) is needed by newproc.
+DATA	runtime·mainPC+0(SB)/8,$runtime·main<ABIInternal>(SB)
+GLOBL	runtime·mainPC(SB),RODATA,$8
+
+TEXT runtime·breakpoint(SB),NOSPLIT,$0-0
+	BYTE	$0xcc
+	RET
+
+TEXT runtime·asminit(SB),NOSPLIT,$0-0
+	// No per-thread init.
+	RET
+
+TEXT runtime·mstart(SB),NOSPLIT|TOPFRAME,$0
+	CALL	runtime·mstart0(SB)
+	RET // not reached
+
+/*
+ *  go-routine
+ */
+
+// func gogo(buf *gobuf)
+// restore state from Gobuf; longjmp
+TEXT runtime·gogo(SB), NOSPLIT, $0-8
+	MOVQ	buf+0(FP), BX		// gobuf
+	MOVQ	gobuf_g(BX), DX
+	MOVQ	0(DX), CX		// make sure g != nil
+	JMP	gogo<>(SB)
+
+TEXT gogo<>(SB), NOSPLIT, $0
+	get_tls(CX)
+	MOVQ	DX, g(CX)
+	MOVQ	DX, R14		// set the g register
+	MOVQ	gobuf_sp(BX), SP	// restore SP
+	MOVQ	gobuf_ret(BX), AX
+	MOVQ	gobuf_ctxt(BX), DX
+	MOVQ	gobuf_bp(BX), BP
+	MOVQ	$0, gobuf_sp(BX)	// clear to help garbage collector
+	MOVQ	$0, gobuf_ret(BX)
+	MOVQ	$0, gobuf_ctxt(BX)
+	MOVQ	$0, gobuf_bp(BX)
+	MOVQ	gobuf_pc(BX), BX
+	JMP	BX
+
+// func mcall(fn func(*g))
+// Switch to m->g0's stack, call fn(g).
+// Fn must never return. It should gogo(&g->sched)
+// to keep running g.
+TEXT runtime·mcall<ABIInternal>(SB), NOSPLIT, $0-8
+	MOVQ	AX, DX	// DX = fn
+
+	// save state in g->sched
+	MOVQ	0(SP), BX	// caller's PC
+	MOVQ	BX, (g_sched+gobuf_pc)(R14)
+	LEAQ	fn+0(FP), BX	// caller's SP
+	MOVQ	BX, (g_sched+gobuf_sp)(R14)
+	MOVQ	BP, (g_sched+gobuf_bp)(R14)
+
+	// switch to m->g0 & its stack, call fn
+	MOVQ	g_m(R14), BX
+	MOVQ	m_g0(BX), SI	// SI = g.m.g0
+	CMPQ	SI, R14	// if g == m->g0 call badmcall
+	JNE	goodm
+	JMP	runtime·badmcall(SB)
+goodm:
+	MOVQ	R14, AX		// AX (and arg 0) = g
+	MOVQ	SI, R14		// g = g.m.g0
+	get_tls(CX)		// Set G in TLS
+	MOVQ	R14, g(CX)
+	MOVQ	(g_sched+gobuf_sp)(R14), SP	// sp = g0.sched.sp
+	PUSHQ	AX	// open up space for fn's arg spill slot
+	MOVQ	0(DX), R12
+	CALL	R12		// fn(g)
+	POPQ	AX
+	JMP	runtime·badmcall2(SB)
+	RET
+
+// systemstack_switch is a dummy routine that systemstack leaves at the bottom
+// of the G stack. We need to distinguish the routine that
+// lives at the bottom of the G stack from the one that lives
+// at the top of the system stack because the one at the top of
+// the system stack terminates the stack walk (see topofstack()).
+TEXT runtime·systemstack_switch(SB), NOSPLIT, $0-0
+	RET
+
+// func systemstack(fn func())
+TEXT runtime·systemstack(SB), NOSPLIT, $0-8
+	MOVQ	fn+0(FP), DI	// DI = fn
+	get_tls(CX)
+	MOVQ	g(CX), AX	// AX = g
+	MOVQ	g_m(AX), BX	// BX = m
+
+	CMPQ	AX, m_gsignal(BX)
+	JEQ	noswitch
+
+	MOVQ	m_g0(BX), DX	// DX = g0
+	CMPQ	AX, DX
+	JEQ	noswitch
+
+	CMPQ	AX, m_curg(BX)
+	JNE	bad
+
+	// switch stacks
+	// save our state in g->sched. Pretend to
+	// be systemstack_switch if the G stack is scanned.
+	CALL	gosave_systemstack_switch<>(SB)
+
+	// switch to g0
+	MOVQ	DX, g(CX)
+	MOVQ	DX, R14 // set the g register
+	MOVQ	(g_sched+gobuf_sp)(DX), BX
+	MOVQ	BX, SP
+
+	// call target function
+	MOVQ	DI, DX
+	MOVQ	0(DI), DI
+	CALL	DI
+
+	// switch back to g
+	get_tls(CX)
+	MOVQ	g(CX), AX
+	MOVQ	g_m(AX), BX
+	MOVQ	m_curg(BX), AX
+	MOVQ	AX, g(CX)
+	MOVQ	(g_sched+gobuf_sp)(AX), SP
+	MOVQ	$0, (g_sched+gobuf_sp)(AX)
+	RET
+
+noswitch:
+	// already on m stack; tail call the function
+	// Using a tail call here cleans up tracebacks since we won't stop
+	// at an intermediate systemstack.
+	MOVQ	DI, DX
+	MOVQ	0(DI), DI
+	JMP	DI
+
+bad:
+	// Bad: g is not gsignal, not g0, not curg. What is it?
+	MOVQ	$runtime·badsystemstack(SB), AX
+	CALL	AX
+	INT	$3
+
+
+/*
+ * support for morestack
+ */
+
+// Called during function prolog when more stack is needed.
+//
+// The traceback routines see morestack on a g0 as being
+// the top of a stack (for example, morestack calling newstack
+// calling the scheduler calling newm calling gc), so we must
+// record an argument size. For that purpose, it has no arguments.
+TEXT runtime·morestack(SB),NOSPLIT,$0-0
+	// Cannot grow scheduler stack (m->g0).
+	get_tls(CX)
+	MOVQ	g(CX), BX
+	MOVQ	g_m(BX), BX
+	MOVQ	m_g0(BX), SI
+	CMPQ	g(CX), SI
+	JNE	3(PC)
+	CALL	runtime·badmorestackg0(SB)
+	CALL	runtime·abort(SB)
+
+	// Cannot grow signal stack (m->gsignal).
+	MOVQ	m_gsignal(BX), SI
+	CMPQ	g(CX), SI
+	JNE	3(PC)
+	CALL	runtime·badmorestackgsignal(SB)
+	CALL	runtime·abort(SB)
+
+	// Called from f.
+	// Set m->morebuf to f's caller.
+	NOP	SP	// tell vet SP changed - stop checking offsets
+	MOVQ	8(SP), AX	// f's caller's PC
+	MOVQ	AX, (m_morebuf+gobuf_pc)(BX)
+	LEAQ	16(SP), AX	// f's caller's SP
+	MOVQ	AX, (m_morebuf+gobuf_sp)(BX)
+	get_tls(CX)
+	MOVQ	g(CX), SI
+	MOVQ	SI, (m_morebuf+gobuf_g)(BX)
+
+	// Set g->sched to context in f.
+	MOVQ	0(SP), AX // f's PC
+	MOVQ	AX, (g_sched+gobuf_pc)(SI)
+	LEAQ	8(SP), AX // f's SP
+	MOVQ	AX, (g_sched+gobuf_sp)(SI)
+	MOVQ	BP, (g_sched+gobuf_bp)(SI)
+	MOVQ	DX, (g_sched+gobuf_ctxt)(SI)
+
+	// Call newstack on m->g0's stack.
+	MOVQ	m_g0(BX), BX
+	MOVQ	BX, g(CX)
+	MOVQ	(g_sched+gobuf_sp)(BX), SP
+	CALL	runtime·newstack(SB)
+	CALL	runtime·abort(SB)	// crash if newstack returns
+	RET
+
+// morestack but not preserving ctxt.
+TEXT runtime·morestack_noctxt(SB),NOSPLIT,$0
+	MOVL	$0, DX
+	JMP	runtime·morestack(SB)
+
+// spillArgs stores return values from registers to a *internal/abi.RegArgs in R12.
+TEXT ·spillArgs(SB),NOSPLIT,$0-0
+	MOVQ AX, 0(R12)
+	MOVQ BX, 8(R12)
+	MOVQ CX, 16(R12)
+	MOVQ DI, 24(R12)
+	MOVQ SI, 32(R12)
+	MOVQ R8, 40(R12)
+	MOVQ R9, 48(R12)
+	MOVQ R10, 56(R12)
+	MOVQ R11, 64(R12)
+	MOVQ X0, 72(R12)
+	MOVQ X1, 80(R12)
+	MOVQ X2, 88(R12)
+	MOVQ X3, 96(R12)
+	MOVQ X4, 104(R12)
+	MOVQ X5, 112(R12)
+	MOVQ X6, 120(R12)
+	MOVQ X7, 128(R12)
+	MOVQ X8, 136(R12)
+	MOVQ X9, 144(R12)
+	MOVQ X10, 152(R12)
+	MOVQ X11, 160(R12)
+	MOVQ X12, 168(R12)
+	MOVQ X13, 176(R12)
+	MOVQ X14, 184(R12)
+	RET
+
+// unspillArgs loads args into registers from a *internal/abi.RegArgs in R12.
+TEXT ·unspillArgs(SB),NOSPLIT,$0-0
+	MOVQ 0(R12), AX
+	MOVQ 8(R12), BX
+	MOVQ 16(R12), CX
+	MOVQ 24(R12), DI
+	MOVQ 32(R12), SI
+	MOVQ 40(R12), R8
+	MOVQ 48(R12), R9
+	MOVQ 56(R12), R10
+	MOVQ 64(R12), R11
+	MOVQ 72(R12), X0
+	MOVQ 80(R12), X1
+	MOVQ 88(R12), X2
+	MOVQ 96(R12), X3
+	MOVQ 104(R12), X4
+	MOVQ 112(R12), X5
+	MOVQ 120(R12), X6
+	MOVQ 128(R12), X7
+	MOVQ 136(R12), X8
+	MOVQ 144(R12), X9
+	MOVQ 152(R12), X10
+	MOVQ 160(R12), X11
+	MOVQ 168(R12), X12
+	MOVQ 176(R12), X13
+	MOVQ 184(R12), X14
+	RET
+
+// reflectcall: call a function with the given argument list
+// func call(stackArgsType *_type, f *FuncVal, stackArgs *byte, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs).
+// we don't have variable-sized frames, so we use a small number
+// of constant-sized-frame functions to encode a few bits of size in the pc.
+// Caution: ugly multiline assembly macros in your future!
+
+#define DISPATCH(NAME,MAXSIZE)		\
+	CMPQ	CX, $MAXSIZE;		\
+	JA	3(PC);			\
+	MOVQ	$NAME(SB), AX;		\
+	JMP	AX
+// Note: can't just "JMP NAME(SB)" - bad inlining results.
+
+TEXT ·reflectcall(SB), NOSPLIT, $0-48
+	MOVLQZX frameSize+32(FP), CX
+	DISPATCH(runtime·call16, 16)
+	DISPATCH(runtime·call32, 32)
+	DISPATCH(runtime·call64, 64)
+	DISPATCH(runtime·call128, 128)
+	DISPATCH(runtime·call256, 256)
+	DISPATCH(runtime·call512, 512)
+	DISPATCH(runtime·call1024, 1024)
+	DISPATCH(runtime·call2048, 2048)
+	DISPATCH(runtime·call4096, 4096)
+	DISPATCH(runtime·call8192, 8192)
+	DISPATCH(runtime·call16384, 16384)
+	DISPATCH(runtime·call32768, 32768)
+	DISPATCH(runtime·call65536, 65536)
+	DISPATCH(runtime·call131072, 131072)
+	DISPATCH(runtime·call262144, 262144)
+	DISPATCH(runtime·call524288, 524288)
+	DISPATCH(runtime·call1048576, 1048576)
+	DISPATCH(runtime·call2097152, 2097152)
+	DISPATCH(runtime·call4194304, 4194304)
+	DISPATCH(runtime·call8388608, 8388608)
+	DISPATCH(runtime·call16777216, 16777216)
+	DISPATCH(runtime·call33554432, 33554432)
+	DISPATCH(runtime·call67108864, 67108864)
+	DISPATCH(runtime·call134217728, 134217728)
+	DISPATCH(runtime·call268435456, 268435456)
+	DISPATCH(runtime·call536870912, 536870912)
+	DISPATCH(runtime·call1073741824, 1073741824)
+	MOVQ	$runtime·badreflectcall(SB), AX
+	JMP	AX
+
+#define CALLFN(NAME,MAXSIZE)			\
+TEXT NAME(SB), WRAPPER, $MAXSIZE-48;		\
+	NO_LOCAL_POINTERS;			\
+	/* copy arguments to stack */		\
+	MOVQ	stackArgs+16(FP), SI;		\
+	MOVLQZX stackArgsSize+24(FP), CX;		\
+	MOVQ	SP, DI;				\
+	REP;MOVSB;				\
+	/* set up argument registers */		\
+	MOVQ    regArgs+40(FP), R12;		\
+	CALL    ·unspillArgs(SB);		\
+	/* call function */			\
+	MOVQ	f+8(FP), DX;			\
+	PCDATA  $PCDATA_StackMapIndex, $0;	\
+	MOVQ	(DX), R12;			\
+	CALL	R12;				\
+	/* copy register return values back */		\
+	MOVQ    regArgs+40(FP), R12;		\
+	CALL    ·spillArgs(SB);		\
+	MOVLQZX	stackArgsSize+24(FP), CX;		\
+	MOVLQZX	stackRetOffset+28(FP), BX;		\
+	MOVQ	stackArgs+16(FP), DI;		\
+	MOVQ	stackArgsType+0(FP), DX;		\
+	MOVQ	SP, SI;				\
+	ADDQ	BX, DI;				\
+	ADDQ	BX, SI;				\
+	SUBQ	BX, CX;				\
+	CALL	callRet<>(SB);			\
+	RET
+
+// callRet copies return values back at the end of call*. This is a
+// separate function so it can allocate stack space for the arguments
+// to reflectcallmove. It does not follow the Go ABI; it expects its
+// arguments in registers.
+TEXT callRet<>(SB), NOSPLIT, $40-0
+	NO_LOCAL_POINTERS
+	MOVQ	DX, 0(SP)
+	MOVQ	DI, 8(SP)
+	MOVQ	SI, 16(SP)
+	MOVQ	CX, 24(SP)
+	MOVQ	R12, 32(SP)
+	CALL	runtime·reflectcallmove(SB)
+	RET
+
+CALLFN(·call16, 16)
+CALLFN(·call32, 32)
+CALLFN(·call64, 64)
+CALLFN(·call128, 128)
+CALLFN(·call256, 256)
+CALLFN(·call512, 512)
+CALLFN(·call1024, 1024)
+CALLFN(·call2048, 2048)
+CALLFN(·call4096, 4096)
+CALLFN(·call8192, 8192)
+CALLFN(·call16384, 16384)
+CALLFN(·call32768, 32768)
+CALLFN(·call65536, 65536)
+CALLFN(·call131072, 131072)
+CALLFN(·call262144, 262144)
+CALLFN(·call524288, 524288)
+CALLFN(·call1048576, 1048576)
+CALLFN(·call2097152, 2097152)
+CALLFN(·call4194304, 4194304)
+CALLFN(·call8388608, 8388608)
+CALLFN(·call16777216, 16777216)
+CALLFN(·call33554432, 33554432)
+CALLFN(·call67108864, 67108864)
+CALLFN(·call134217728, 134217728)
+CALLFN(·call268435456, 268435456)
+CALLFN(·call536870912, 536870912)
+CALLFN(·call1073741824, 1073741824)
+
+TEXT runtime·procyield(SB),NOSPLIT,$0-0
+	MOVL	cycles+0(FP), AX
+again:
+	PAUSE
+	SUBL	$1, AX
+	JNZ	again
+	RET
+
+
+TEXT ·publicationBarrier(SB),NOSPLIT,$0-0
+	// Stores are already ordered on x86, so this is just a
+	// compile barrier.
+	RET
+
+// Save state of caller into g->sched,
+// but using fake PC from systemstack_switch.
+// Must only be called from functions with no locals ($0)
+// or else unwinding from systemstack_switch is incorrect.
+// Smashes R9.
+TEXT gosave_systemstack_switch<>(SB),NOSPLIT,$0
+	MOVQ	$runtime·systemstack_switch(SB), R9
+	MOVQ	R9, (g_sched+gobuf_pc)(R14)
+	LEAQ	8(SP), R9
+	MOVQ	R9, (g_sched+gobuf_sp)(R14)
+	MOVQ	$0, (g_sched+gobuf_ret)(R14)
+	MOVQ	BP, (g_sched+gobuf_bp)(R14)
+	// Assert ctxt is zero. See func save.
+	MOVQ	(g_sched+gobuf_ctxt)(R14), R9
+	TESTQ	R9, R9
+	JZ	2(PC)
+	CALL	runtime·abort(SB)
+	RET
+
+// func asmcgocall_no_g(fn, arg unsafe.Pointer)
+// Call fn(arg) aligned appropriately for the gcc ABI.
+// Called on a system stack, and there may be no g yet (during needm).
+TEXT ·asmcgocall_no_g(SB),NOSPLIT,$0-16
+	MOVQ	fn+0(FP), AX
+	MOVQ	arg+8(FP), BX
+	MOVQ	SP, DX
+	SUBQ	$32, SP
+	ANDQ	$~15, SP	// alignment
+	MOVQ	DX, 8(SP)
+	MOVQ	BX, DI		// DI = first argument in AMD64 ABI
+	MOVQ	BX, CX		// CX = first argument in Win64
+	CALL	AX
+	MOVQ	8(SP), DX
+	MOVQ	DX, SP
+	RET
+
+// func asmcgocall(fn, arg unsafe.Pointer) int32
+// Call fn(arg) on the scheduler stack,
+// aligned appropriately for the gcc ABI.
+// See cgocall.go for more details.
+TEXT ·asmcgocall(SB),NOSPLIT,$0-20
+	MOVQ	fn+0(FP), AX
+	MOVQ	arg+8(FP), BX
+
+	MOVQ	SP, DX
+
+	// Figure out if we need to switch to m->g0 stack.
+	// We get called to create new OS threads too, and those
+	// come in on the m->g0 stack already. Or we might already
+	// be on the m->gsignal stack.
+	get_tls(CX)
+	MOVQ	g(CX), DI
+	CMPQ	DI, $0
+	JEQ	nosave
+	MOVQ	g_m(DI), R8
+	MOVQ	m_gsignal(R8), SI
+	CMPQ	DI, SI
+	JEQ	nosave
+	MOVQ	m_g0(R8), SI
+	CMPQ	DI, SI
+	JEQ	nosave
+
+	// Switch to system stack.
+	CALL	gosave_systemstack_switch<>(SB)
+	MOVQ	SI, g(CX)
+	MOVQ	(g_sched+gobuf_sp)(SI), SP
+
+	// Now on a scheduling stack (a pthread-created stack).
+	// Make sure we have enough room for 4 stack-backed fast-call
+	// registers as per windows amd64 calling convention.
+	SUBQ	$64, SP
+	ANDQ	$~15, SP	// alignment for gcc ABI
+	MOVQ	DI, 48(SP)	// save g
+	MOVQ	(g_stack+stack_hi)(DI), DI
+	SUBQ	DX, DI
+	MOVQ	DI, 40(SP)	// save depth in stack (can't just save SP, as stack might be copied during a callback)
+	MOVQ	BX, DI		// DI = first argument in AMD64 ABI
+	MOVQ	BX, CX		// CX = first argument in Win64
+	CALL	AX
+
+	// Restore registers, g, stack pointer.
+	get_tls(CX)
+	MOVQ	48(SP), DI
+	MOVQ	(g_stack+stack_hi)(DI), SI
+	SUBQ	40(SP), SI
+	MOVQ	DI, g(CX)
+	MOVQ	SI, SP
+
+	MOVL	AX, ret+16(FP)
+	RET
+
+nosave:
+	// Running on a system stack, perhaps even without a g.
+	// Having no g can happen during thread creation or thread teardown
+	// (see needm/dropm on Solaris, for example).
+	// This code is like the above sequence but without saving/restoring g
+	// and without worrying about the stack moving out from under us
+	// (because we're on a system stack, not a goroutine stack).
+	// The above code could be used directly if already on a system stack,
+	// but then the only path through this code would be a rare case on Solaris.
+	// Using this code for all "already on system stack" calls exercises it more,
+	// which should help keep it correct.
+	SUBQ	$64, SP
+	ANDQ	$~15, SP
+	MOVQ	$0, 48(SP)		// where above code stores g, in case someone looks during debugging
+	MOVQ	DX, 40(SP)	// save original stack pointer
+	MOVQ	BX, DI		// DI = first argument in AMD64 ABI
+	MOVQ	BX, CX		// CX = first argument in Win64
+	CALL	AX
+	MOVQ	40(SP), SI	// restore original stack pointer
+	MOVQ	SI, SP
+	MOVL	AX, ret+16(FP)
+	RET
+
+#ifdef GOOS_windows
+// Dummy TLS that's used on Windows so that we don't crash trying
+// to restore the G register in needm. needm and its callees are
+// very careful never to actually use the G, the TLS just can't be
+// unset since we're in Go code.
+GLOBL zeroTLS<>(SB),RODATA,$const_tlsSize
+#endif
+
+// func cgocallback(fn, frame unsafe.Pointer, ctxt uintptr)
+// See cgocall.go for more details.
+TEXT ·cgocallback(SB),NOSPLIT,$24-24
+	NO_LOCAL_POINTERS
+
+	// If g is nil, Go did not create the current thread.
+	// Call needm to obtain one m for temporary use.
+	// In this case, we're running on the thread stack, so there's
+	// lots of space, but the linker doesn't know. Hide the call from
+	// the linker analysis by using an indirect call through AX.
+	get_tls(CX)
+#ifdef GOOS_windows
+	MOVL	$0, BX
+	CMPQ	CX, $0
+	JEQ	2(PC)
+#endif
+	MOVQ	g(CX), BX
+	CMPQ	BX, $0
+	JEQ	needm
+	MOVQ	g_m(BX), BX
+	MOVQ	BX, savedm-8(SP)	// saved copy of oldm
+	JMP	havem
+needm:
+#ifdef GOOS_windows
+	// Set up a dummy TLS value. needm is careful not to use it,
+	// but it needs to be there to prevent autogenerated code from
+	// crashing when it loads from it.
+	// We don't need to clear it or anything later because needm
+	// will set up TLS properly.
+	MOVQ	$zeroTLS<>(SB), DI
+	CALL	runtime·settls(SB)
+#endif
+	// On some platforms (Windows) we cannot call needm through
+	// an ABI wrapper because there's no TLS set up, and the ABI
+	// wrapper will try to restore the G register (R14) from TLS.
+	// Clear X15 because Go expects it and we're not calling
+	// through a wrapper, but otherwise avoid setting the G
+	// register in the wrapper and call needm directly. It
+	// takes no arguments and doesn't return any values so
+	// there's no need to handle that. Clear R14 so that there's
+	// a bad value in there, in case needm tries to use it.
+	XORPS	X15, X15
+	XORQ    R14, R14
+	MOVQ	$runtime·needm<ABIInternal>(SB), AX
+	CALL	AX
+	MOVQ	$0, savedm-8(SP) // dropm on return
+	get_tls(CX)
+	MOVQ	g(CX), BX
+	MOVQ	g_m(BX), BX
+
+	// Set m->sched.sp = SP, so that if a panic happens
+	// during the function we are about to execute, it will
+	// have a valid SP to run on the g0 stack.
+	// The next few lines (after the havem label)
+	// will save this SP onto the stack and then write
+	// the same SP back to m->sched.sp. That seems redundant,
+	// but if an unrecovered panic happens, unwindm will
+	// restore the g->sched.sp from the stack location
+	// and then systemstack will try to use it. If we don't set it here,
+	// that restored SP will be uninitialized (typically 0) and
+	// will not be usable.
+	MOVQ	m_g0(BX), SI
+	MOVQ	SP, (g_sched+gobuf_sp)(SI)
+
+havem:
+	// Now there's a valid m, and we're running on its m->g0.
+	// Save current m->g0->sched.sp on stack and then set it to SP.
+	// Save current sp in m->g0->sched.sp in preparation for
+	// switch back to m->curg stack.
+	// NOTE: unwindm knows that the saved g->sched.sp is at 0(SP).
+	MOVQ	m_g0(BX), SI
+	MOVQ	(g_sched+gobuf_sp)(SI), AX
+	MOVQ	AX, 0(SP)
+	MOVQ	SP, (g_sched+gobuf_sp)(SI)
+
+	// Switch to m->curg stack and call runtime.cgocallbackg.
+	// Because we are taking over the execution of m->curg
+	// but *not* resuming what had been running, we need to
+	// save that information (m->curg->sched) so we can restore it.
+	// We can restore m->curg->sched.sp easily, because calling
+	// runtime.cgocallbackg leaves SP unchanged upon return.
+	// To save m->curg->sched.pc, we push it onto the curg stack and
+	// open a frame the same size as cgocallback's g0 frame.
+	// Once we switch to the curg stack, the pushed PC will appear
+	// to be the return PC of cgocallback, so that the traceback
+	// will seamlessly trace back into the earlier calls.
+	MOVQ	m_curg(BX), SI
+	MOVQ	SI, g(CX)
+	MOVQ	(g_sched+gobuf_sp)(SI), DI  // prepare stack as DI
+	MOVQ	(g_sched+gobuf_pc)(SI), BX
+	MOVQ	BX, -8(DI)  // "push" return PC on the g stack
+	// Gather our arguments into registers.
+	MOVQ	fn+0(FP), BX
+	MOVQ	frame+8(FP), CX
+	MOVQ	ctxt+16(FP), DX
+	// Compute the size of the frame, including return PC and, if
+	// GOEXPERIMENT=framepointer, the saved base pointer
+	LEAQ	fn+0(FP), AX
+	SUBQ	SP, AX   // AX is our actual frame size
+	SUBQ	AX, DI   // Allocate the same frame size on the g stack
+	MOVQ	DI, SP
+
+	MOVQ	BX, 0(SP)
+	MOVQ	CX, 8(SP)
+	MOVQ	DX, 16(SP)
+	MOVQ	$runtime·cgocallbackg(SB), AX
+	CALL	AX	// indirect call to bypass nosplit check. We're on a different stack now.
+
+	// Compute the size of the frame again. FP and SP have
+	// completely different values here than they did above,
+	// but only their difference matters.
+	LEAQ	fn+0(FP), AX
+	SUBQ	SP, AX
+
+	// Restore g->sched (== m->curg->sched) from saved values.
+	get_tls(CX)
+	MOVQ	g(CX), SI
+	MOVQ	SP, DI
+	ADDQ	AX, DI
+	MOVQ	-8(DI), BX
+	MOVQ	BX, (g_sched+gobuf_pc)(SI)
+	MOVQ	DI, (g_sched+gobuf_sp)(SI)
+
+	// Switch back to m->g0's stack and restore m->g0->sched.sp.
+	// (Unlike m->curg, the g0 goroutine never uses sched.pc,
+	// so we do not have to restore it.)
+	MOVQ	g(CX), BX
+	MOVQ	g_m(BX), BX
+	MOVQ	m_g0(BX), SI
+	MOVQ	SI, g(CX)
+	MOVQ	(g_sched+gobuf_sp)(SI), SP
+	MOVQ	0(SP), AX
+	MOVQ	AX, (g_sched+gobuf_sp)(SI)
+
+	// If the m on entry was nil, we called needm above to borrow an m
+	// for the duration of the call. Since the call is over, return it with dropm.
+	MOVQ	savedm-8(SP), BX
+	CMPQ	BX, $0
+	JNE	done
+	MOVQ	$runtime·dropm(SB), AX
+	CALL	AX
+#ifdef GOOS_windows
+	// We need to clear the TLS pointer in case the next
+	// thread that comes into Go tries to reuse that space
+	// but uses the same M.
+	XORQ	DI, DI
+	CALL	runtime·settls(SB)
+#endif
+done:
+
+	// Done!
+	RET
+
+// func setg(gg *g)
+// set g. for use by needm.
+TEXT runtime·setg(SB), NOSPLIT, $0-8
+	MOVQ	gg+0(FP), BX
+	get_tls(CX)
+	MOVQ	BX, g(CX)
+	RET
+
+// void setg_gcc(G*); set g called from gcc.
+TEXT setg_gcc<>(SB),NOSPLIT,$0
+	get_tls(AX)
+	MOVQ	DI, g(AX)
+	MOVQ	DI, R14 // set the g register
+	RET
+
+TEXT runtime·abort(SB),NOSPLIT,$0-0
+	INT	$3
+loop:
+	JMP	loop
+
+// check that SP is in range [g->stack.lo, g->stack.hi)
+TEXT runtime·stackcheck(SB), NOSPLIT, $0-0
+	get_tls(CX)
+	MOVQ	g(CX), AX
+	CMPQ	(g_stack+stack_hi)(AX), SP
+	JHI	2(PC)
+	CALL	runtime·abort(SB)
+	CMPQ	SP, (g_stack+stack_lo)(AX)
+	JHI	2(PC)
+	CALL	runtime·abort(SB)
+	RET
+
+// func cputicks() int64
+TEXT runtime·cputicks(SB),NOSPLIT,$0-0
+	CMPB	internal∕cpu·X86+const_offsetX86HasRDTSCP(SB), $1
+	JNE	fences
+	// Instruction stream serializing RDTSCP is supported.
+	// RDTSCP is supported by Intel Nehalem (2008) and
+	// AMD K8 Rev. F (2006) and newer.
+	RDTSCP
+done:
+	SHLQ	$32, DX
+	ADDQ	DX, AX
+	MOVQ	AX, ret+0(FP)
+	RET
+fences:
+	// MFENCE is instruction stream serializing and flushes the
+	// store buffers on AMD. The serialization semantics of LFENCE on AMD
+	// are dependent on MSR C001_1029 and CPU generation.
+	// LFENCE on Intel does wait for all previous instructions to have executed.
+	// Intel recommends MFENCE;LFENCE in its manuals before RDTSC to have all
+	// previous instructions executed and all previous loads and stores to globally visible.
+	// Using MFENCE;LFENCE here aligns the serializing properties without
+	// runtime detection of CPU manufacturer.
+	MFENCE
+	LFENCE
+	RDTSC
+	JMP done
+
+// func memhash(p unsafe.Pointer, h, s uintptr) uintptr
+// hash function using AES hardware instructions
+TEXT runtime·memhash<ABIInternal>(SB),NOSPLIT,$0-32
+	// AX = ptr to data
+	// BX = seed
+	// CX = size
+	CMPB	runtime·useAeshash(SB), $0
+	JEQ	noaes
+	JMP	aeshashbody<>(SB)
+noaes:
+	JMP	runtime·memhashFallback<ABIInternal>(SB)
+
+// func strhash(p unsafe.Pointer, h uintptr) uintptr
+TEXT runtime·strhash<ABIInternal>(SB),NOSPLIT,$0-24
+	// AX = ptr to string struct
+	// BX = seed
+	CMPB	runtime·useAeshash(SB), $0
+	JEQ	noaes
+	MOVQ	8(AX), CX	// length of string
+	MOVQ	(AX), AX	// string data
+	JMP	aeshashbody<>(SB)
+noaes:
+	JMP	runtime·strhashFallback<ABIInternal>(SB)
+
+// AX: data
+// BX: hash seed
+// CX: length
+// At return: AX = return value
+TEXT aeshashbody<>(SB),NOSPLIT,$0-0
+	// Fill an SSE register with our seeds.
+	MOVQ	BX, X0				// 64 bits of per-table hash seed
+	PINSRW	$4, CX, X0			// 16 bits of length
+	PSHUFHW $0, X0, X0			// repeat length 4 times total
+	MOVO	X0, X1				// save unscrambled seed
+	PXOR	runtime·aeskeysched(SB), X0	// xor in per-process seed
+	AESENC	X0, X0				// scramble seed
+
+	CMPQ	CX, $16
+	JB	aes0to15
+	JE	aes16
+	CMPQ	CX, $32
+	JBE	aes17to32
+	CMPQ	CX, $64
+	JBE	aes33to64
+	CMPQ	CX, $128
+	JBE	aes65to128
+	JMP	aes129plus
+
+aes0to15:
+	TESTQ	CX, CX
+	JE	aes0
+
+	ADDQ	$16, AX
+	TESTW	$0xff0, AX
+	JE	endofpage
+
+	// 16 bytes loaded at this address won't cross
+	// a page boundary, so we can load it directly.
+	MOVOU	-16(AX), X1
+	ADDQ	CX, CX
+	MOVQ	$masks<>(SB), AX
+	PAND	(AX)(CX*8), X1
+final1:
+	PXOR	X0, X1	// xor data with seed
+	AESENC	X1, X1	// scramble combo 3 times
+	AESENC	X1, X1
+	AESENC	X1, X1
+	MOVQ	X1, AX	// return X1
+	RET
+
+endofpage:
+	// address ends in 1111xxxx. Might be up against
+	// a page boundary, so load ending at last byte.
+	// Then shift bytes down using pshufb.
+	MOVOU	-32(AX)(CX*1), X1
+	ADDQ	CX, CX
+	MOVQ	$shifts<>(SB), AX
+	PSHUFB	(AX)(CX*8), X1
+	JMP	final1
+
+aes0:
+	// Return scrambled input seed
+	AESENC	X0, X0
+	MOVQ	X0, AX	// return X0
+	RET
+
+aes16:
+	MOVOU	(AX), X1
+	JMP	final1
+
+aes17to32:
+	// make second starting seed
+	PXOR	runtime·aeskeysched+16(SB), X1
+	AESENC	X1, X1
+
+	// load data to be hashed
+	MOVOU	(AX), X2
+	MOVOU	-16(AX)(CX*1), X3
+
+	// xor with seed
+	PXOR	X0, X2
+	PXOR	X1, X3
+
+	// scramble 3 times
+	AESENC	X2, X2
+	AESENC	X3, X3
+	AESENC	X2, X2
+	AESENC	X3, X3
+	AESENC	X2, X2
+	AESENC	X3, X3
+
+	// combine results
+	PXOR	X3, X2
+	MOVQ	X2, AX	// return X2
+	RET
+
+aes33to64:
+	// make 3 more starting seeds
+	MOVO	X1, X2
+	MOVO	X1, X3
+	PXOR	runtime·aeskeysched+16(SB), X1
+	PXOR	runtime·aeskeysched+32(SB), X2
+	PXOR	runtime·aeskeysched+48(SB), X3
+	AESENC	X1, X1
+	AESENC	X2, X2
+	AESENC	X3, X3
+
+	MOVOU	(AX), X4
+	MOVOU	16(AX), X5
+	MOVOU	-32(AX)(CX*1), X6
+	MOVOU	-16(AX)(CX*1), X7
+
+	PXOR	X0, X4
+	PXOR	X1, X5
+	PXOR	X2, X6
+	PXOR	X3, X7
+
+	AESENC	X4, X4
+	AESENC	X5, X5
+	AESENC	X6, X6
+	AESENC	X7, X7
+
+	AESENC	X4, X4
+	AESENC	X5, X5
+	AESENC	X6, X6
+	AESENC	X7, X7
+
+	AESENC	X4, X4
+	AESENC	X5, X5
+	AESENC	X6, X6
+	AESENC	X7, X7
+
+	PXOR	X6, X4
+	PXOR	X7, X5
+	PXOR	X5, X4
+	MOVQ	X4, AX	// return X4
+	RET
+
+aes65to128:
+	// make 7 more starting seeds
+	MOVO	X1, X2
+	MOVO	X1, X3
+	MOVO	X1, X4
+	MOVO	X1, X5
+	MOVO	X1, X6
+	MOVO	X1, X7
+	PXOR	runtime·aeskeysched+16(SB), X1
+	PXOR	runtime·aeskeysched+32(SB), X2
+	PXOR	runtime·aeskeysched+48(SB), X3
+	PXOR	runtime·aeskeysched+64(SB), X4
+	PXOR	runtime·aeskeysched+80(SB), X5
+	PXOR	runtime·aeskeysched+96(SB), X6
+	PXOR	runtime·aeskeysched+112(SB), X7
+	AESENC	X1, X1
+	AESENC	X2, X2
+	AESENC	X3, X3
+	AESENC	X4, X4
+	AESENC	X5, X5
+	AESENC	X6, X6
+	AESENC	X7, X7
+
+	// load data
+	MOVOU	(AX), X8
+	MOVOU	16(AX), X9
+	MOVOU	32(AX), X10
+	MOVOU	48(AX), X11
+	MOVOU	-64(AX)(CX*1), X12
+	MOVOU	-48(AX)(CX*1), X13
+	MOVOU	-32(AX)(CX*1), X14
+	MOVOU	-16(AX)(CX*1), X15
+
+	// xor with seed
+	PXOR	X0, X8
+	PXOR	X1, X9
+	PXOR	X2, X10
+	PXOR	X3, X11
+	PXOR	X4, X12
+	PXOR	X5, X13
+	PXOR	X6, X14
+	PXOR	X7, X15
+
+	// scramble 3 times
+	AESENC	X8, X8
+	AESENC	X9, X9
+	AESENC	X10, X10
+	AESENC	X11, X11
+	AESENC	X12, X12
+	AESENC	X13, X13
+	AESENC	X14, X14
+	AESENC	X15, X15
+
+	AESENC	X8, X8
+	AESENC	X9, X9
+	AESENC	X10, X10
+	AESENC	X11, X11
+	AESENC	X12, X12
+	AESENC	X13, X13
+	AESENC	X14, X14
+	AESENC	X15, X15
+
+	AESENC	X8, X8
+	AESENC	X9, X9
+	AESENC	X10, X10
+	AESENC	X11, X11
+	AESENC	X12, X12
+	AESENC	X13, X13
+	AESENC	X14, X14
+	AESENC	X15, X15
+
+	// combine results
+	PXOR	X12, X8
+	PXOR	X13, X9
+	PXOR	X14, X10
+	PXOR	X15, X11
+	PXOR	X10, X8
+	PXOR	X11, X9
+	PXOR	X9, X8
+	// X15 must be zero on return
+	PXOR	X15, X15
+	MOVQ	X8, AX	// return X8
+	RET
+
+aes129plus:
+	// make 7 more starting seeds
+	MOVO	X1, X2
+	MOVO	X1, X3
+	MOVO	X1, X4
+	MOVO	X1, X5
+	MOVO	X1, X6
+	MOVO	X1, X7
+	PXOR	runtime·aeskeysched+16(SB), X1
+	PXOR	runtime·aeskeysched+32(SB), X2
+	PXOR	runtime·aeskeysched+48(SB), X3
+	PXOR	runtime·aeskeysched+64(SB), X4
+	PXOR	runtime·aeskeysched+80(SB), X5
+	PXOR	runtime·aeskeysched+96(SB), X6
+	PXOR	runtime·aeskeysched+112(SB), X7
+	AESENC	X1, X1
+	AESENC	X2, X2
+	AESENC	X3, X3
+	AESENC	X4, X4
+	AESENC	X5, X5
+	AESENC	X6, X6
+	AESENC	X7, X7
+
+	// start with last (possibly overlapping) block
+	MOVOU	-128(AX)(CX*1), X8
+	MOVOU	-112(AX)(CX*1), X9
+	MOVOU	-96(AX)(CX*1), X10
+	MOVOU	-80(AX)(CX*1), X11
+	MOVOU	-64(AX)(CX*1), X12
+	MOVOU	-48(AX)(CX*1), X13
+	MOVOU	-32(AX)(CX*1), X14
+	MOVOU	-16(AX)(CX*1), X15
+
+	// xor in seed
+	PXOR	X0, X8
+	PXOR	X1, X9
+	PXOR	X2, X10
+	PXOR	X3, X11
+	PXOR	X4, X12
+	PXOR	X5, X13
+	PXOR	X6, X14
+	PXOR	X7, X15
+
+	// compute number of remaining 128-byte blocks
+	DECQ	CX
+	SHRQ	$7, CX
+
+aesloop:
+	// scramble state
+	AESENC	X8, X8
+	AESENC	X9, X9
+	AESENC	X10, X10
+	AESENC	X11, X11
+	AESENC	X12, X12
+	AESENC	X13, X13
+	AESENC	X14, X14
+	AESENC	X15, X15
+
+	// scramble state, xor in a block
+	MOVOU	(AX), X0
+	MOVOU	16(AX), X1
+	MOVOU	32(AX), X2
+	MOVOU	48(AX), X3
+	AESENC	X0, X8
+	AESENC	X1, X9
+	AESENC	X2, X10
+	AESENC	X3, X11
+	MOVOU	64(AX), X4
+	MOVOU	80(AX), X5
+	MOVOU	96(AX), X6
+	MOVOU	112(AX), X7
+	AESENC	X4, X12
+	AESENC	X5, X13
+	AESENC	X6, X14
+	AESENC	X7, X15
+
+	ADDQ	$128, AX
+	DECQ	CX
+	JNE	aesloop
+
+	// 3 more scrambles to finish
+	AESENC	X8, X8
+	AESENC	X9, X9
+	AESENC	X10, X10
+	AESENC	X11, X11
+	AESENC	X12, X12
+	AESENC	X13, X13
+	AESENC	X14, X14
+	AESENC	X15, X15
+	AESENC	X8, X8
+	AESENC	X9, X9
+	AESENC	X10, X10
+	AESENC	X11, X11
+	AESENC	X12, X12
+	AESENC	X13, X13
+	AESENC	X14, X14
+	AESENC	X15, X15
+	AESENC	X8, X8
+	AESENC	X9, X9
+	AESENC	X10, X10
+	AESENC	X11, X11
+	AESENC	X12, X12
+	AESENC	X13, X13
+	AESENC	X14, X14
+	AESENC	X15, X15
+
+	PXOR	X12, X8
+	PXOR	X13, X9
+	PXOR	X14, X10
+	PXOR	X15, X11
+	PXOR	X10, X8
+	PXOR	X11, X9
+	PXOR	X9, X8
+	// X15 must be zero on return
+	PXOR	X15, X15
+	MOVQ	X8, AX	// return X8
+	RET
+
+// func memhash32(p unsafe.Pointer, h uintptr) uintptr
+// ABIInternal for performance.
+TEXT runtime·memhash32<ABIInternal>(SB),NOSPLIT,$0-24
+	// AX = ptr to data
+	// BX = seed
+	CMPB	runtime·useAeshash(SB), $0
+	JEQ	noaes
+	MOVQ	BX, X0	// X0 = seed
+	PINSRD	$2, (AX), X0	// data
+	AESENC	runtime·aeskeysched+0(SB), X0
+	AESENC	runtime·aeskeysched+16(SB), X0
+	AESENC	runtime·aeskeysched+32(SB), X0
+	MOVQ	X0, AX	// return X0
+	RET
+noaes:
+	JMP	runtime·memhash32Fallback<ABIInternal>(SB)
+
+// func memhash64(p unsafe.Pointer, h uintptr) uintptr
+// ABIInternal for performance.
+TEXT runtime·memhash64<ABIInternal>(SB),NOSPLIT,$0-24
+	// AX = ptr to data
+	// BX = seed
+	CMPB	runtime·useAeshash(SB), $0
+	JEQ	noaes
+	MOVQ	BX, X0	// X0 = seed
+	PINSRQ	$1, (AX), X0	// data
+	AESENC	runtime·aeskeysched+0(SB), X0
+	AESENC	runtime·aeskeysched+16(SB), X0
+	AESENC	runtime·aeskeysched+32(SB), X0
+	MOVQ	X0, AX	// return X0
+	RET
+noaes:
+	JMP	runtime·memhash64Fallback<ABIInternal>(SB)
+
+// simple mask to get rid of data in the high part of the register.
+DATA masks<>+0x00(SB)/8, $0x0000000000000000
+DATA masks<>+0x08(SB)/8, $0x0000000000000000
+DATA masks<>+0x10(SB)/8, $0x00000000000000ff
+DATA masks<>+0x18(SB)/8, $0x0000000000000000
+DATA masks<>+0x20(SB)/8, $0x000000000000ffff
+DATA masks<>+0x28(SB)/8, $0x0000000000000000
+DATA masks<>+0x30(SB)/8, $0x0000000000ffffff
+DATA masks<>+0x38(SB)/8, $0x0000000000000000
+DATA masks<>+0x40(SB)/8, $0x00000000ffffffff
+DATA masks<>+0x48(SB)/8, $0x0000000000000000
+DATA masks<>+0x50(SB)/8, $0x000000ffffffffff
+DATA masks<>+0x58(SB)/8, $0x0000000000000000
+DATA masks<>+0x60(SB)/8, $0x0000ffffffffffff
+DATA masks<>+0x68(SB)/8, $0x0000000000000000
+DATA masks<>+0x70(SB)/8, $0x00ffffffffffffff
+DATA masks<>+0x78(SB)/8, $0x0000000000000000
+DATA masks<>+0x80(SB)/8, $0xffffffffffffffff
+DATA masks<>+0x88(SB)/8, $0x0000000000000000
+DATA masks<>+0x90(SB)/8, $0xffffffffffffffff
+DATA masks<>+0x98(SB)/8, $0x00000000000000ff
+DATA masks<>+0xa0(SB)/8, $0xffffffffffffffff
+DATA masks<>+0xa8(SB)/8, $0x000000000000ffff
+DATA masks<>+0xb0(SB)/8, $0xffffffffffffffff
+DATA masks<>+0xb8(SB)/8, $0x0000000000ffffff
+DATA masks<>+0xc0(SB)/8, $0xffffffffffffffff
+DATA masks<>+0xc8(SB)/8, $0x00000000ffffffff
+DATA masks<>+0xd0(SB)/8, $0xffffffffffffffff
+DATA masks<>+0xd8(SB)/8, $0x000000ffffffffff
+DATA masks<>+0xe0(SB)/8, $0xffffffffffffffff
+DATA masks<>+0xe8(SB)/8, $0x0000ffffffffffff
+DATA masks<>+0xf0(SB)/8, $0xffffffffffffffff
+DATA masks<>+0xf8(SB)/8, $0x00ffffffffffffff
+GLOBL masks<>(SB),RODATA,$256
+
+// func checkASM() bool
+TEXT ·checkASM(SB),NOSPLIT,$0-1
+	// check that masks<>(SB) and shifts<>(SB) are aligned to 16-byte
+	MOVQ	$masks<>(SB), AX
+	MOVQ	$shifts<>(SB), BX
+	ORQ	BX, AX
+	TESTQ	$15, AX
+	SETEQ	ret+0(FP)
+	RET
+
+// these are arguments to pshufb. They move data down from
+// the high bytes of the register to the low bytes of the register.
+// index is how many bytes to move.
+DATA shifts<>+0x00(SB)/8, $0x0000000000000000
+DATA shifts<>+0x08(SB)/8, $0x0000000000000000
+DATA shifts<>+0x10(SB)/8, $0xffffffffffffff0f
+DATA shifts<>+0x18(SB)/8, $0xffffffffffffffff
+DATA shifts<>+0x20(SB)/8, $0xffffffffffff0f0e
+DATA shifts<>+0x28(SB)/8, $0xffffffffffffffff
+DATA shifts<>+0x30(SB)/8, $0xffffffffff0f0e0d
+DATA shifts<>+0x38(SB)/8, $0xffffffffffffffff
+DATA shifts<>+0x40(SB)/8, $0xffffffff0f0e0d0c
+DATA shifts<>+0x48(SB)/8, $0xffffffffffffffff
+DATA shifts<>+0x50(SB)/8, $0xffffff0f0e0d0c0b
+DATA shifts<>+0x58(SB)/8, $0xffffffffffffffff
+DATA shifts<>+0x60(SB)/8, $0xffff0f0e0d0c0b0a
+DATA shifts<>+0x68(SB)/8, $0xffffffffffffffff
+DATA shifts<>+0x70(SB)/8, $0xff0f0e0d0c0b0a09
+DATA shifts<>+0x78(SB)/8, $0xffffffffffffffff
+DATA shifts<>+0x80(SB)/8, $0x0f0e0d0c0b0a0908
+DATA shifts<>+0x88(SB)/8, $0xffffffffffffffff
+DATA shifts<>+0x90(SB)/8, $0x0e0d0c0b0a090807
+DATA shifts<>+0x98(SB)/8, $0xffffffffffffff0f
+DATA shifts<>+0xa0(SB)/8, $0x0d0c0b0a09080706
+DATA shifts<>+0xa8(SB)/8, $0xffffffffffff0f0e
+DATA shifts<>+0xb0(SB)/8, $0x0c0b0a0908070605
+DATA shifts<>+0xb8(SB)/8, $0xffffffffff0f0e0d
+DATA shifts<>+0xc0(SB)/8, $0x0b0a090807060504
+DATA shifts<>+0xc8(SB)/8, $0xffffffff0f0e0d0c
+DATA shifts<>+0xd0(SB)/8, $0x0a09080706050403
+DATA shifts<>+0xd8(SB)/8, $0xffffff0f0e0d0c0b
+DATA shifts<>+0xe0(SB)/8, $0x0908070605040302
+DATA shifts<>+0xe8(SB)/8, $0xffff0f0e0d0c0b0a
+DATA shifts<>+0xf0(SB)/8, $0x0807060504030201
+DATA shifts<>+0xf8(SB)/8, $0xff0f0e0d0c0b0a09
+GLOBL shifts<>(SB),RODATA,$256
+
+TEXT runtime·return0(SB), NOSPLIT, $0
+	MOVL	$0, AX
+	RET
+
+
+// Called from cgo wrappers, this function returns g->m->curg.stack.hi.
+// Must obey the gcc calling convention.
+TEXT _cgo_topofstack(SB),NOSPLIT,$0
+	get_tls(CX)
+	MOVQ	g(CX), AX
+	MOVQ	g_m(AX), AX
+	MOVQ	m_curg(AX), AX
+	MOVQ	(g_stack+stack_hi)(AX), AX
+	RET
+
+// The top-most function running on a goroutine
+// returns to goexit+PCQuantum.
+TEXT runtime·goexit(SB),NOSPLIT|TOPFRAME,$0-0
+	BYTE	$0x90	// NOP
+	CALL	runtime·goexit1(SB)	// does not return
+	// traceback from goexit1 must hit code range of goexit
+	BYTE	$0x90	// NOP
+
+// This is called from .init_array and follows the platform, not Go, ABI.
+TEXT runtime·addmoduledata(SB),NOSPLIT,$0-0
+	PUSHQ	R15 // The access to global variables below implicitly uses R15, which is callee-save
+	MOVQ	runtime·lastmoduledatap(SB), AX
+	MOVQ	DI, moduledata_next(AX)
+	MOVQ	DI, runtime·lastmoduledatap(SB)
+	POPQ	R15
+	RET
+
+// Initialize special registers then jump to sigpanic.
+// This function is injected from the signal handler for panicking
+// signals. It is quite painful to set X15 in the signal context,
+// so we do it here.
+TEXT ·sigpanic0(SB),NOSPLIT,$0-0
+	get_tls(R14)
+	MOVQ	g(R14), R14
+#ifndef GOOS_plan9
+	XORPS	X15, X15
+#endif
+	JMP	·sigpanic<ABIInternal>(SB)
+
+// gcWriteBarrier performs a heap pointer write and informs the GC.
+//
+// gcWriteBarrier does NOT follow the Go ABI. It takes two arguments:
+// - DI is the destination of the write
+// - AX is the value being written at DI
+// It clobbers FLAGS. It does not clobber any general-purpose registers,
+// but may clobber others (e.g., SSE registers).
+// Defined as ABIInternal since it does not use the stack-based Go ABI.
+TEXT runtime·gcWriteBarrier<ABIInternal>(SB),NOSPLIT,$112
+	// Save the registers clobbered by the fast path. This is slightly
+	// faster than having the caller spill these.
+	MOVQ	R12, 96(SP)
+	MOVQ	R13, 104(SP)
+	// TODO: Consider passing g.m.p in as an argument so they can be shared
+	// across a sequence of write barriers.
+	MOVQ	g_m(R14), R13
+	MOVQ	m_p(R13), R13
+	MOVQ	(p_wbBuf+wbBuf_next)(R13), R12
+	// Increment wbBuf.next position.
+	LEAQ	16(R12), R12
+	MOVQ	R12, (p_wbBuf+wbBuf_next)(R13)
+	CMPQ	R12, (p_wbBuf+wbBuf_end)(R13)
+	// Record the write.
+	MOVQ	AX, -16(R12)	// Record value
+	// Note: This turns bad pointer writes into bad
+	// pointer reads, which could be confusing. We could avoid
+	// reading from obviously bad pointers, which would
+	// take care of the vast majority of these. We could
+	// patch this up in the signal handler, or use XCHG to
+	// combine the read and the write.
+	MOVQ	(DI), R13
+	MOVQ	R13, -8(R12)	// Record *slot
+	// Is the buffer full? (flags set in CMPQ above)
+	JEQ	flush
+ret:
+	MOVQ	96(SP), R12
+	MOVQ	104(SP), R13
+	// Do the write.
+	MOVQ	AX, (DI)
+	RET
+
+flush:
+	// Save all general purpose registers since these could be
+	// clobbered by wbBufFlush and were not saved by the caller.
+	// It is possible for wbBufFlush to clobber other registers
+	// (e.g., SSE registers), but the compiler takes care of saving
+	// those in the caller if necessary. This strikes a balance
+	// with registers that are likely to be used.
+	//
+	// We don't have type information for these, but all code under
+	// here is NOSPLIT, so nothing will observe these.
+	//
+	// TODO: We could strike a different balance; e.g., saving X0
+	// and not saving GP registers that are less likely to be used.
+	MOVQ	DI, 0(SP)	// Also first argument to wbBufFlush
+	MOVQ	AX, 8(SP)	// Also second argument to wbBufFlush
+	MOVQ	BX, 16(SP)
+	MOVQ	CX, 24(SP)
+	MOVQ	DX, 32(SP)
+	// DI already saved
+	MOVQ	SI, 40(SP)
+	MOVQ	BP, 48(SP)
+	MOVQ	R8, 56(SP)
+	MOVQ	R9, 64(SP)
+	MOVQ	R10, 72(SP)
+	MOVQ	R11, 80(SP)
+	// R12 already saved
+	// R13 already saved
+	// R14 is g
+	MOVQ	R15, 88(SP)
+
+	// This takes arguments DI and AX
+	CALL	runtime·wbBufFlush(SB)
+
+	MOVQ	0(SP), DI
+	MOVQ	8(SP), AX
+	MOVQ	16(SP), BX
+	MOVQ	24(SP), CX
+	MOVQ	32(SP), DX
+	MOVQ	40(SP), SI
+	MOVQ	48(SP), BP
+	MOVQ	56(SP), R8
+	MOVQ	64(SP), R9
+	MOVQ	72(SP), R10
+	MOVQ	80(SP), R11
+	MOVQ	88(SP), R15
+	JMP	ret
+
+// gcWriteBarrierCX is gcWriteBarrier, but with args in DI and CX.
+// Defined as ABIInternal since it does not use the stable Go ABI.
+TEXT runtime·gcWriteBarrierCX<ABIInternal>(SB),NOSPLIT,$0
+	XCHGQ CX, AX
+	CALL runtime·gcWriteBarrier<ABIInternal>(SB)
+	XCHGQ CX, AX
+	RET
+
+// gcWriteBarrierDX is gcWriteBarrier, but with args in DI and DX.
+// Defined as ABIInternal since it does not use the stable Go ABI.
+TEXT runtime·gcWriteBarrierDX<ABIInternal>(SB),NOSPLIT,$0
+	XCHGQ DX, AX
+	CALL runtime·gcWriteBarrier<ABIInternal>(SB)
+	XCHGQ DX, AX
+	RET
+
+// gcWriteBarrierBX is gcWriteBarrier, but with args in DI and BX.
+// Defined as ABIInternal since it does not use the stable Go ABI.
+TEXT runtime·gcWriteBarrierBX<ABIInternal>(SB),NOSPLIT,$0
+	XCHGQ BX, AX
+	CALL runtime·gcWriteBarrier<ABIInternal>(SB)
+	XCHGQ BX, AX
+	RET
+
+// gcWriteBarrierBP is gcWriteBarrier, but with args in DI and BP.
+// Defined as ABIInternal since it does not use the stable Go ABI.
+TEXT runtime·gcWriteBarrierBP<ABIInternal>(SB),NOSPLIT,$0
+	XCHGQ BP, AX
+	CALL runtime·gcWriteBarrier<ABIInternal>(SB)
+	XCHGQ BP, AX
+	RET
+
+// gcWriteBarrierSI is gcWriteBarrier, but with args in DI and SI.
+// Defined as ABIInternal since it does not use the stable Go ABI.
+TEXT runtime·gcWriteBarrierSI<ABIInternal>(SB),NOSPLIT,$0
+	XCHGQ SI, AX
+	CALL runtime·gcWriteBarrier<ABIInternal>(SB)
+	XCHGQ SI, AX
+	RET
+
+// gcWriteBarrierR8 is gcWriteBarrier, but with args in DI and R8.
+// Defined as ABIInternal since it does not use the stable Go ABI.
+TEXT runtime·gcWriteBarrierR8<ABIInternal>(SB),NOSPLIT,$0
+	XCHGQ R8, AX
+	CALL runtime·gcWriteBarrier<ABIInternal>(SB)
+	XCHGQ R8, AX
+	RET
+
+// gcWriteBarrierR9 is gcWriteBarrier, but with args in DI and R9.
+// Defined as ABIInternal since it does not use the stable Go ABI.
+TEXT runtime·gcWriteBarrierR9<ABIInternal>(SB),NOSPLIT,$0
+	XCHGQ R9, AX
+	CALL runtime·gcWriteBarrier<ABIInternal>(SB)
+	XCHGQ R9, AX
+	RET
+
+DATA	debugCallFrameTooLarge<>+0x00(SB)/20, $"call frame too large"
+GLOBL	debugCallFrameTooLarge<>(SB), RODATA, $20	// Size duplicated below
+
+// debugCallV2 is the entry point for debugger-injected function
+// calls on running goroutines. It informs the runtime that a
+// debug call has been injected and creates a call frame for the
+// debugger to fill in.
+//
+// To inject a function call, a debugger should:
+// 1. Check that the goroutine is in state _Grunning and that
+//    there are at least 256 bytes free on the stack.
+// 2. Push the current PC on the stack (updating SP).
+// 3. Write the desired argument frame size at SP-16 (using the SP
+//    after step 2).
+// 4. Save all machine registers (including flags and XMM registers)
+//    so they can be restored later by the debugger.
+// 5. Set the PC to debugCallV2 and resume execution.
+//
+// If the goroutine is in state _Grunnable, then it's not generally
+// safe to inject a call because it may return out via other runtime
+// operations. Instead, the debugger should unwind the stack to find
+// the return to non-runtime code, add a temporary breakpoint there,
+// and inject the call once that breakpoint is hit.
+//
+// If the goroutine is in any other state, it's not safe to inject a call.
+//
+// This function communicates back to the debugger by setting R12 and
+// invoking INT3 to raise a breakpoint signal. See the comments in the
+// implementation for the protocol the debugger is expected to
+// follow. InjectDebugCall in the runtime tests demonstrates this protocol.
+//
+// The debugger must ensure that any pointers passed to the function
+// obey escape analysis requirements. Specifically, it must not pass
+// a stack pointer to an escaping argument. debugCallV2 cannot check
+// this invariant.
+//
+// This is ABIInternal because Go code injects its PC directly into new
+// goroutine stacks.
+TEXT runtime·debugCallV2<ABIInternal>(SB),NOSPLIT,$152-0
+	// Save all registers that may contain pointers so they can be
+	// conservatively scanned.
+	//
+	// We can't do anything that might clobber any of these
+	// registers before this.
+	MOVQ	R15, r15-(14*8+8)(SP)
+	MOVQ	R14, r14-(13*8+8)(SP)
+	MOVQ	R13, r13-(12*8+8)(SP)
+	MOVQ	R12, r12-(11*8+8)(SP)
+	MOVQ	R11, r11-(10*8+8)(SP)
+	MOVQ	R10, r10-(9*8+8)(SP)
+	MOVQ	R9, r9-(8*8+8)(SP)
+	MOVQ	R8, r8-(7*8+8)(SP)
+	MOVQ	DI, di-(6*8+8)(SP)
+	MOVQ	SI, si-(5*8+8)(SP)
+	MOVQ	BP, bp-(4*8+8)(SP)
+	MOVQ	BX, bx-(3*8+8)(SP)
+	MOVQ	DX, dx-(2*8+8)(SP)
+	// Save the frame size before we clobber it. Either of the last
+	// saves could clobber this depending on whether there's a saved BP.
+	MOVQ	frameSize-24(FP), DX	// aka -16(RSP) before prologue
+	MOVQ	CX, cx-(1*8+8)(SP)
+	MOVQ	AX, ax-(0*8+8)(SP)
+
+	// Save the argument frame size.
+	MOVQ	DX, frameSize-128(SP)
+
+	// Perform a safe-point check.
+	MOVQ	retpc-8(FP), AX	// Caller's PC
+	MOVQ	AX, 0(SP)
+	CALL	runtime·debugCallCheck(SB)
+	MOVQ	8(SP), AX
+	TESTQ	AX, AX
+	JZ	good
+	// The safety check failed. Put the reason string at the top
+	// of the stack.
+	MOVQ	AX, 0(SP)
+	MOVQ	16(SP), AX
+	MOVQ	AX, 8(SP)
+	// Set R12 to 8 and invoke INT3. The debugger should get the
+	// reason a call can't be injected from the top of the stack
+	// and resume execution.
+	MOVQ	$8, R12
+	BYTE	$0xcc
+	JMP	restore
+
+good:
+	// Registers are saved and it's safe to make a call.
+	// Open up a call frame, moving the stack if necessary.
+	//
+	// Once the frame is allocated, this will set R12 to 0 and
+	// invoke INT3. The debugger should write the argument
+	// frame for the call at SP, set up argument registers, push
+	// the trapping PC on the stack, set the PC to the function to
+	// call, set RDX to point to the closure (if a closure call),
+	// and resume execution.
+	//
+	// If the function returns, this will set R12 to 1 and invoke
+	// INT3. The debugger can then inspect any return value saved
+	// on the stack at SP and in registers and resume execution again.
+	//
+	// If the function panics, this will set R12 to 2 and invoke INT3.
+	// The interface{} value of the panic will be at SP. The debugger
+	// can inspect the panic value and resume execution again.
+#define DEBUG_CALL_DISPATCH(NAME,MAXSIZE)	\
+	CMPQ	AX, $MAXSIZE;			\
+	JA	5(PC);				\
+	MOVQ	$NAME(SB), AX;			\
+	MOVQ	AX, 0(SP);			\
+	CALL	runtime·debugCallWrap(SB);	\
+	JMP	restore
+
+	MOVQ	frameSize-128(SP), AX
+	DEBUG_CALL_DISPATCH(debugCall32<>, 32)
+	DEBUG_CALL_DISPATCH(debugCall64<>, 64)
+	DEBUG_CALL_DISPATCH(debugCall128<>, 128)
+	DEBUG_CALL_DISPATCH(debugCall256<>, 256)
+	DEBUG_CALL_DISPATCH(debugCall512<>, 512)
+	DEBUG_CALL_DISPATCH(debugCall1024<>, 1024)
+	DEBUG_CALL_DISPATCH(debugCall2048<>, 2048)
+	DEBUG_CALL_DISPATCH(debugCall4096<>, 4096)
+	DEBUG_CALL_DISPATCH(debugCall8192<>, 8192)
+	DEBUG_CALL_DISPATCH(debugCall16384<>, 16384)
+	DEBUG_CALL_DISPATCH(debugCall32768<>, 32768)
+	DEBUG_CALL_DISPATCH(debugCall65536<>, 65536)
+	// The frame size is too large. Report the error.
+	MOVQ	$debugCallFrameTooLarge<>(SB), AX
+	MOVQ	AX, 0(SP)
+	MOVQ	$20, 8(SP) // length of debugCallFrameTooLarge string
+	MOVQ	$8, R12
+	BYTE	$0xcc
+	JMP	restore
+
+restore:
+	// Calls and failures resume here.
+	//
+	// Set R12 to 16 and invoke INT3. The debugger should restore
+	// all registers except RIP and RSP and resume execution.
+	MOVQ	$16, R12
+	BYTE	$0xcc
+	// We must not modify flags after this point.
+
+	// Restore pointer-containing registers, which may have been
+	// modified from the debugger's copy by stack copying.
+	MOVQ	ax-(0*8+8)(SP), AX
+	MOVQ	cx-(1*8+8)(SP), CX
+	MOVQ	dx-(2*8+8)(SP), DX
+	MOVQ	bx-(3*8+8)(SP), BX
+	MOVQ	bp-(4*8+8)(SP), BP
+	MOVQ	si-(5*8+8)(SP), SI
+	MOVQ	di-(6*8+8)(SP), DI
+	MOVQ	r8-(7*8+8)(SP), R8
+	MOVQ	r9-(8*8+8)(SP), R9
+	MOVQ	r10-(9*8+8)(SP), R10
+	MOVQ	r11-(10*8+8)(SP), R11
+	MOVQ	r12-(11*8+8)(SP), R12
+	MOVQ	r13-(12*8+8)(SP), R13
+	MOVQ	r14-(13*8+8)(SP), R14
+	MOVQ	r15-(14*8+8)(SP), R15
+
+	RET
+
+// runtime.debugCallCheck assumes that functions defined with the
+// DEBUG_CALL_FN macro are safe points to inject calls.
+#define DEBUG_CALL_FN(NAME,MAXSIZE)		\
+TEXT NAME(SB),WRAPPER,$MAXSIZE-0;		\
+	NO_LOCAL_POINTERS;			\
+	MOVQ	$0, R12;				\
+	BYTE	$0xcc;				\
+	MOVQ	$1, R12;				\
+	BYTE	$0xcc;				\
+	RET
+DEBUG_CALL_FN(debugCall32<>, 32)
+DEBUG_CALL_FN(debugCall64<>, 64)
+DEBUG_CALL_FN(debugCall128<>, 128)
+DEBUG_CALL_FN(debugCall256<>, 256)
+DEBUG_CALL_FN(debugCall512<>, 512)
+DEBUG_CALL_FN(debugCall1024<>, 1024)
+DEBUG_CALL_FN(debugCall2048<>, 2048)
+DEBUG_CALL_FN(debugCall4096<>, 4096)
+DEBUG_CALL_FN(debugCall8192<>, 8192)
+DEBUG_CALL_FN(debugCall16384<>, 16384)
+DEBUG_CALL_FN(debugCall32768<>, 32768)
+DEBUG_CALL_FN(debugCall65536<>, 65536)
+
+// func debugCallPanicked(val interface{})
+TEXT runtime·debugCallPanicked(SB),NOSPLIT,$16-16
+	// Copy the panic value to the top of stack.
+	MOVQ	val_type+0(FP), AX
+	MOVQ	AX, 0(SP)
+	MOVQ	val_data+8(FP), AX
+	MOVQ	AX, 8(SP)
+	MOVQ	$2, R12
+	BYTE	$0xcc
+	RET
+
+// Note: these functions use a special calling convention to save generated code space.
+// Arguments are passed in registers, but the space for those arguments are allocated
+// in the caller's stack frame. These stubs write the args into that stack space and
+// then tail call to the corresponding runtime handler.
+// The tail call makes these stubs disappear in backtraces.
+// Defined as ABIInternal since they do not use the stack-based Go ABI.
+TEXT runtime·panicIndex<ABIInternal>(SB),NOSPLIT,$0-16
+	MOVQ	CX, BX
+	JMP	runtime·goPanicIndex<ABIInternal>(SB)
+TEXT runtime·panicIndexU<ABIInternal>(SB),NOSPLIT,$0-16
+	MOVQ	CX, BX
+	JMP	runtime·goPanicIndexU<ABIInternal>(SB)
+TEXT runtime·panicSliceAlen<ABIInternal>(SB),NOSPLIT,$0-16
+	MOVQ	CX, AX
+	MOVQ	DX, BX
+	JMP	runtime·goPanicSliceAlen<ABIInternal>(SB)
+TEXT runtime·panicSliceAlenU<ABIInternal>(SB),NOSPLIT,$0-16
+	MOVQ	CX, AX
+	MOVQ	DX, BX
+	JMP	runtime·goPanicSliceAlenU<ABIInternal>(SB)
+TEXT runtime·panicSliceAcap<ABIInternal>(SB),NOSPLIT,$0-16
+	MOVQ	CX, AX
+	MOVQ	DX, BX
+	JMP	runtime·goPanicSliceAcap<ABIInternal>(SB)
+TEXT runtime·panicSliceAcapU<ABIInternal>(SB),NOSPLIT,$0-16
+	MOVQ	CX, AX
+	MOVQ	DX, BX
+	JMP	runtime·goPanicSliceAcapU<ABIInternal>(SB)
+TEXT runtime·panicSliceB<ABIInternal>(SB),NOSPLIT,$0-16
+	MOVQ	CX, BX
+	JMP	runtime·goPanicSliceB<ABIInternal>(SB)
+TEXT runtime·panicSliceBU<ABIInternal>(SB),NOSPLIT,$0-16
+	MOVQ	CX, BX
+	JMP	runtime·goPanicSliceBU<ABIInternal>(SB)
+TEXT runtime·panicSlice3Alen<ABIInternal>(SB),NOSPLIT,$0-16
+	MOVQ	DX, AX
+	JMP	runtime·goPanicSlice3Alen<ABIInternal>(SB)
+TEXT runtime·panicSlice3AlenU<ABIInternal>(SB),NOSPLIT,$0-16
+	MOVQ	DX, AX
+	JMP	runtime·goPanicSlice3AlenU<ABIInternal>(SB)
+TEXT runtime·panicSlice3Acap<ABIInternal>(SB),NOSPLIT,$0-16
+	MOVQ	DX, AX
+	JMP	runtime·goPanicSlice3Acap<ABIInternal>(SB)
+TEXT runtime·panicSlice3AcapU<ABIInternal>(SB),NOSPLIT,$0-16
+	MOVQ	DX, AX
+	JMP	runtime·goPanicSlice3AcapU<ABIInternal>(SB)
+TEXT runtime·panicSlice3B<ABIInternal>(SB),NOSPLIT,$0-16
+	MOVQ	CX, AX
+	MOVQ	DX, BX
+	JMP	runtime·goPanicSlice3B<ABIInternal>(SB)
+TEXT runtime·panicSlice3BU<ABIInternal>(SB),NOSPLIT,$0-16
+	MOVQ	CX, AX
+	MOVQ	DX, BX
+	JMP	runtime·goPanicSlice3BU<ABIInternal>(SB)
+TEXT runtime·panicSlice3C<ABIInternal>(SB),NOSPLIT,$0-16
+	MOVQ	CX, BX
+	JMP	runtime·goPanicSlice3C<ABIInternal>(SB)
+TEXT runtime·panicSlice3CU<ABIInternal>(SB),NOSPLIT,$0-16
+	MOVQ	CX, BX
+	JMP	runtime·goPanicSlice3CU<ABIInternal>(SB)
+TEXT runtime·panicSliceConvert<ABIInternal>(SB),NOSPLIT,$0-16
+	MOVQ	DX, AX
+	JMP	runtime·goPanicSliceConvert<ABIInternal>(SB)
+
+#ifdef GOOS_android
+// Use the free TLS_SLOT_APP slot #2 on Android Q.
+// Earlier androids are set up in gcc_android.c.
+DATA runtime·tls_g+0(SB)/8, $16
+GLOBL runtime·tls_g+0(SB), NOPTR, $8
+#endif
+
+// The compiler and assembler's -spectre=ret mode rewrites
+// all indirect CALL AX / JMP AX instructions to be
+// CALL retpolineAX / JMP retpolineAX.
+// See https://support.google.com/faqs/answer/7625886.
+#define RETPOLINE(reg) \
+	/*   CALL setup */     BYTE $0xE8; BYTE $(2+2); BYTE $0; BYTE $0; BYTE $0;	\
+	/* nospec: */									\
+	/*   PAUSE */           BYTE $0xF3; BYTE $0x90;					\
+	/*   JMP nospec */      BYTE $0xEB; BYTE $-(2+2);				\
+	/* setup: */									\
+	/*   MOVQ AX, 0(SP) */  BYTE $0x48|((reg&8)>>1); BYTE $0x89;			\
+	                        BYTE $0x04|((reg&7)<<3); BYTE $0x24;			\
+	/*   RET */             BYTE $0xC3
+
+TEXT runtime·retpolineAX(SB),NOSPLIT,$0; RETPOLINE(0)
+TEXT runtime·retpolineCX(SB),NOSPLIT,$0; RETPOLINE(1)
+TEXT runtime·retpolineDX(SB),NOSPLIT,$0; RETPOLINE(2)
+TEXT runtime·retpolineBX(SB),NOSPLIT,$0; RETPOLINE(3)
+/* SP is 4, can't happen / magic encodings */
+TEXT runtime·retpolineBP(SB),NOSPLIT,$0; RETPOLINE(5)
+TEXT runtime·retpolineSI(SB),NOSPLIT,$0; RETPOLINE(6)
+TEXT runtime·retpolineDI(SB),NOSPLIT,$0; RETPOLINE(7)
+TEXT runtime·retpolineR8(SB),NOSPLIT,$0; RETPOLINE(8)
+TEXT runtime·retpolineR9(SB),NOSPLIT,$0; RETPOLINE(9)
+TEXT runtime·retpolineR10(SB),NOSPLIT,$0; RETPOLINE(10)
+TEXT runtime·retpolineR11(SB),NOSPLIT,$0; RETPOLINE(11)
+TEXT runtime·retpolineR12(SB),NOSPLIT,$0; RETPOLINE(12)
+TEXT runtime·retpolineR13(SB),NOSPLIT,$0; RETPOLINE(13)
+TEXT runtime·retpolineR14(SB),NOSPLIT,$0; RETPOLINE(14)
+TEXT runtime·retpolineR15(SB),NOSPLIT,$0; RETPOLINE(15)
diff --git a/contrib/go/_std_1.18/src/runtime/atomic_pointer.go b/contrib/go/_std_1.19/src/runtime/atomic_pointer.go
index b8f0c22c63..b8f0c22c63 100644
--- a/contrib/go/_std_1.18/src/runtime/atomic_pointer.go
+++ b/contrib/go/_std_1.19/src/runtime/atomic_pointer.go
diff --git a/contrib/go/_std_1.18/src/runtime/cgo.go b/contrib/go/_std_1.19/src/runtime/cgo.go
index d90468240d..d90468240d 100644
--- a/contrib/go/_std_1.18/src/runtime/cgo.go
+++ b/contrib/go/_std_1.19/src/runtime/cgo.go
diff --git a/contrib/go/_std_1.18/src/runtime/cgo/abi_amd64.h b/contrib/go/_std_1.19/src/runtime/cgo/abi_amd64.h
index 9949435fe9..9949435fe9 100644
--- a/contrib/go/_std_1.18/src/runtime/cgo/abi_amd64.h
+++ b/contrib/go/_std_1.19/src/runtime/cgo/abi_amd64.h
diff --git a/contrib/go/_std_1.18/src/runtime/cgo/asm_amd64.s b/contrib/go/_std_1.19/src/runtime/cgo/asm_amd64.s
index 386299c548..386299c548 100644
--- a/contrib/go/_std_1.18/src/runtime/cgo/asm_amd64.s
+++ b/contrib/go/_std_1.19/src/runtime/cgo/asm_amd64.s
diff --git a/contrib/go/_std_1.19/src/runtime/cgo/callbacks.go b/contrib/go/_std_1.19/src/runtime/cgo/callbacks.go
new file mode 100644
index 0000000000..e7c8ef3e07
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/cgo/callbacks.go
@@ -0,0 +1,107 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cgo
+
+import "unsafe"
+
+// These utility functions are available to be called from code
+// compiled with gcc via crosscall2.
+
+// The declaration of crosscall2 is:
+//   void crosscall2(void (*fn)(void *), void *, int);
+//
+// We need to export the symbol crosscall2 in order to support
+// callbacks from shared libraries. This applies regardless of
+// linking mode.
+//
+// Compatibility note: SWIG uses crosscall2 in exactly one situation:
+// to call _cgo_panic using the pattern shown below. We need to keep
+// that pattern working. In particular, crosscall2 actually takes four
+// arguments, but it works to call it with three arguments when
+// calling _cgo_panic.
+//
+//go:cgo_export_static crosscall2
+//go:cgo_export_dynamic crosscall2
+
+// Panic. The argument is converted into a Go string.
+
+// Call like this in code compiled with gcc:
+//   struct { const char *p; } a;
+//   a.p = /* string to pass to panic */;
+//   crosscall2(_cgo_panic, &a, sizeof a);
+//   /* The function call will not return.  */
+
+// TODO: We should export a regular C function to panic, change SWIG
+// to use that instead of the above pattern, and then we can drop
+// backwards-compatibility from crosscall2 and stop exporting it.
+
+//go:linkname _runtime_cgo_panic_internal runtime._cgo_panic_internal
+func _runtime_cgo_panic_internal(p *byte)
+
+//go:linkname _cgo_panic _cgo_panic
+//go:cgo_export_static _cgo_panic
+//go:cgo_export_dynamic _cgo_panic
+func _cgo_panic(a *struct{ cstr *byte }) {
+	_runtime_cgo_panic_internal(a.cstr)
+}
+
+//go:cgo_import_static x_cgo_init
+//go:linkname x_cgo_init x_cgo_init
+//go:linkname _cgo_init _cgo_init
+var x_cgo_init byte
+var _cgo_init = &x_cgo_init
+
+//go:cgo_import_static x_cgo_thread_start
+//go:linkname x_cgo_thread_start x_cgo_thread_start
+//go:linkname _cgo_thread_start _cgo_thread_start
+var x_cgo_thread_start byte
+var _cgo_thread_start = &x_cgo_thread_start
+
+// Creates a new system thread without updating any Go state.
+//
+// This method is invoked during shared library loading to create a new OS
+// thread to perform the runtime initialization. This method is similar to
+// _cgo_sys_thread_start except that it doesn't update any Go state.
+
+//go:cgo_import_static x_cgo_sys_thread_create
+//go:linkname x_cgo_sys_thread_create x_cgo_sys_thread_create
+//go:linkname _cgo_sys_thread_create _cgo_sys_thread_create
+var x_cgo_sys_thread_create byte
+var _cgo_sys_thread_create = &x_cgo_sys_thread_create
+
+// Notifies that the runtime has been initialized.
+//
+// We currently block at every CGO entry point (via _cgo_wait_runtime_init_done)
+// to ensure that the runtime has been initialized before the CGO call is
+// executed. This is necessary for shared libraries where we kickoff runtime
+// initialization in a separate thread and return without waiting for this
+// thread to complete the init.
+
+//go:cgo_import_static x_cgo_notify_runtime_init_done
+//go:linkname x_cgo_notify_runtime_init_done x_cgo_notify_runtime_init_done
+//go:linkname _cgo_notify_runtime_init_done _cgo_notify_runtime_init_done
+var x_cgo_notify_runtime_init_done byte
+var _cgo_notify_runtime_init_done = &x_cgo_notify_runtime_init_done
+
+// Sets the traceback context function. See runtime.SetCgoTraceback.
+
+//go:cgo_import_static x_cgo_set_context_function
+//go:linkname x_cgo_set_context_function x_cgo_set_context_function
+//go:linkname _cgo_set_context_function _cgo_set_context_function
+var x_cgo_set_context_function byte
+var _cgo_set_context_function = &x_cgo_set_context_function
+
+// Calls a libc function to execute background work injected via libc
+// interceptors, such as processing pending signals under the thread
+// sanitizer.
+//
+// Left as a nil pointer if no libc interceptors are expected.
+
+//go:cgo_import_static _cgo_yield
+//go:linkname _cgo_yield _cgo_yield
+var _cgo_yield unsafe.Pointer
+
+//go:cgo_export_static _cgo_topofstack
+//go:cgo_export_dynamic _cgo_topofstack
diff --git a/contrib/go/_std_1.18/src/runtime/cgo/callbacks_traceback.go b/contrib/go/_std_1.19/src/runtime/cgo/callbacks_traceback.go
index dae31a8fcd..dae31a8fcd 100644
--- a/contrib/go/_std_1.18/src/runtime/cgo/callbacks_traceback.go
+++ b/contrib/go/_std_1.19/src/runtime/cgo/callbacks_traceback.go
diff --git a/contrib/go/_std_1.19/src/runtime/cgo/cgo.go b/contrib/go/_std_1.19/src/runtime/cgo/cgo.go
new file mode 100644
index 0000000000..298aa63675
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/cgo/cgo.go
@@ -0,0 +1,31 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package cgo contains runtime support for code generated
+by the cgo tool.  See the documentation for the cgo command
+for details on using cgo.
+*/
+package cgo
+
+/*
+
+#cgo darwin,!arm64 LDFLAGS: -lpthread
+#cgo darwin,arm64 LDFLAGS: -framework CoreFoundation
+#cgo dragonfly LDFLAGS: -lpthread
+#cgo freebsd LDFLAGS: -lpthread
+#cgo android LDFLAGS: -llog
+#cgo !android,linux LDFLAGS: -lpthread
+#cgo netbsd LDFLAGS: -lpthread
+#cgo openbsd LDFLAGS: -lpthread
+#cgo aix LDFLAGS: -Wl,-berok
+#cgo solaris LDFLAGS: -lxnet
+#cgo solaris LDFLAGS: -lsocket
+
+#cgo CFLAGS: -Wall -Werror
+
+#cgo solaris CPPFLAGS: -D_POSIX_PTHREAD_SEMANTICS
+
+*/
+import "C"
diff --git a/contrib/go/_std_1.18/src/runtime/cgo/gcc_amd64.S b/contrib/go/_std_1.19/src/runtime/cgo/gcc_amd64.S
index 46699d1d9c..46699d1d9c 100644
--- a/contrib/go/_std_1.18/src/runtime/cgo/gcc_amd64.S
+++ b/contrib/go/_std_1.19/src/runtime/cgo/gcc_amd64.S
diff --git a/contrib/go/_std_1.18/src/runtime/cgo/gcc_context.c b/contrib/go/_std_1.19/src/runtime/cgo/gcc_context.c
index 5fc0abb8bc..5fc0abb8bc 100644
--- a/contrib/go/_std_1.18/src/runtime/cgo/gcc_context.c
+++ b/contrib/go/_std_1.19/src/runtime/cgo/gcc_context.c
diff --git a/contrib/go/_std_1.18/src/runtime/cgo/gcc_darwin_amd64.c b/contrib/go/_std_1.19/src/runtime/cgo/gcc_darwin_amd64.c
index d5b7fd8fd8..d5b7fd8fd8 100644
--- a/contrib/go/_std_1.18/src/runtime/cgo/gcc_darwin_amd64.c
+++ b/contrib/go/_std_1.19/src/runtime/cgo/gcc_darwin_amd64.c
diff --git a/contrib/go/_std_1.18/src/runtime/cgo/gcc_fatalf.c b/contrib/go/_std_1.19/src/runtime/cgo/gcc_fatalf.c
index 597e750f12..597e750f12 100644
--- a/contrib/go/_std_1.18/src/runtime/cgo/gcc_fatalf.c
+++ b/contrib/go/_std_1.19/src/runtime/cgo/gcc_fatalf.c
diff --git a/contrib/go/_std_1.18/src/runtime/cgo/gcc_libinit.c b/contrib/go/_std_1.19/src/runtime/cgo/gcc_libinit.c
index 3304d95fdf..3304d95fdf 100644
--- a/contrib/go/_std_1.18/src/runtime/cgo/gcc_libinit.c
+++ b/contrib/go/_std_1.19/src/runtime/cgo/gcc_libinit.c
diff --git a/contrib/go/_std_1.19/src/runtime/cgo/gcc_linux_amd64.c b/contrib/go/_std_1.19/src/runtime/cgo/gcc_linux_amd64.c
new file mode 100644
index 0000000000..fb164c1a1d
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/cgo/gcc_linux_amd64.c
@@ -0,0 +1,96 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include <pthread.h>
+#include <errno.h>
+#include <string.h> // strerror
+#include <signal.h>
+#include <stdlib.h>
+#include "libcgo.h"
+#include "libcgo_unix.h"
+
+static void* threadentry(void*);
+static void (*setg_gcc)(void*);
+
+// This will be set in gcc_android.c for android-specific customization.
+void (*x_cgo_inittls)(void **tlsg, void **tlsbase) __attribute__((common));
+
+void
+x_cgo_init(G *g, void (*setg)(void*), void **tlsg, void **tlsbase)
+{
+	pthread_attr_t *attr;
+	size_t size;
+
+	/* The memory sanitizer distributed with versions of clang
+	   before 3.8 has a bug: if you call mmap before malloc, mmap
+	   may return an address that is later overwritten by the msan
+	   library.  Avoid this problem by forcing a call to malloc
+	   here, before we ever call malloc.
+
+	   This is only required for the memory sanitizer, so it's
+	   unfortunate that we always run it.  It should be possible
+	   to remove this when we no longer care about versions of
+	   clang before 3.8.  The test for this is
+	   misc/cgo/testsanitizers.
+
+	   GCC works hard to eliminate a seemingly unnecessary call to
+	   malloc, so we actually use the memory we allocate.  */
+
+	setg_gcc = setg;
+	attr = (pthread_attr_t*)malloc(sizeof *attr);
+	if (attr == NULL) {
+		fatalf("malloc failed: %s", strerror(errno));
+	}
+	pthread_attr_init(attr);
+	pthread_attr_getstacksize(attr, &size);
+	g->stacklo = (uintptr)__builtin_frame_address(0) - size + 4096;
+	if (g->stacklo >= g->stackhi)
+		fatalf("bad stack bounds: lo=%p hi=%p\n", g->stacklo, g->stackhi);
+	pthread_attr_destroy(attr);
+	free(attr);
+
+	if (x_cgo_inittls) {
+		x_cgo_inittls(tlsg, tlsbase);
+	}
+}
+
+
+void
+_cgo_sys_thread_start(ThreadStart *ts)
+{
+	pthread_attr_t attr;
+	sigset_t ign, oset;
+	pthread_t p;
+	size_t size;
+	int err;
+
+	sigfillset(&ign);
+	pthread_sigmask(SIG_SETMASK, &ign, &oset);
+
+	pthread_attr_init(&attr);
+	pthread_attr_getstacksize(&attr, &size);
+	// Leave stacklo=0 and set stackhi=size; mstart will do the rest.
+	ts->g->stackhi = size;
+	err = _cgo_try_pthread_create(&p, &attr, threadentry, ts);
+
+	pthread_sigmask(SIG_SETMASK, &oset, nil);
+
+	if (err != 0) {
+		fatalf("pthread_create failed: %s", strerror(err));
+	}
+}
+
+static void*
+threadentry(void *v)
+{
+	ThreadStart ts;
+
+	ts = *(ThreadStart*)v;
+	_cgo_tsan_acquire();
+	free(v);
+	_cgo_tsan_release();
+
+	crosscall_amd64(ts.fn, setg_gcc, (void*)ts.g);
+	return nil;
+}
diff --git a/contrib/go/_std_1.18/src/runtime/cgo/gcc_mmap.c b/contrib/go/_std_1.19/src/runtime/cgo/gcc_mmap.c
index 698a7e3cd2..698a7e3cd2 100644
--- a/contrib/go/_std_1.18/src/runtime/cgo/gcc_mmap.c
+++ b/contrib/go/_std_1.19/src/runtime/cgo/gcc_mmap.c
diff --git a/contrib/go/_std_1.18/src/runtime/cgo/gcc_setenv.c b/contrib/go/_std_1.19/src/runtime/cgo/gcc_setenv.c
index d4f798357a..d4f798357a 100644
--- a/contrib/go/_std_1.18/src/runtime/cgo/gcc_setenv.c
+++ b/contrib/go/_std_1.19/src/runtime/cgo/gcc_setenv.c
diff --git a/contrib/go/_std_1.18/src/runtime/cgo/gcc_sigaction.c b/contrib/go/_std_1.19/src/runtime/cgo/gcc_sigaction.c
index fcf1e50740..fcf1e50740 100644
--- a/contrib/go/_std_1.18/src/runtime/cgo/gcc_sigaction.c
+++ b/contrib/go/_std_1.19/src/runtime/cgo/gcc_sigaction.c
diff --git a/contrib/go/_std_1.18/src/runtime/cgo/gcc_traceback.c b/contrib/go/_std_1.19/src/runtime/cgo/gcc_traceback.c
index 6e9470c43c..6e9470c43c 100644
--- a/contrib/go/_std_1.18/src/runtime/cgo/gcc_traceback.c
+++ b/contrib/go/_std_1.19/src/runtime/cgo/gcc_traceback.c
diff --git a/contrib/go/_std_1.18/src/runtime/cgo/gcc_util.c b/contrib/go/_std_1.19/src/runtime/cgo/gcc_util.c
index 3fcb48cc8d..3fcb48cc8d 100644
--- a/contrib/go/_std_1.18/src/runtime/cgo/gcc_util.c
+++ b/contrib/go/_std_1.19/src/runtime/cgo/gcc_util.c
diff --git a/contrib/go/_std_1.18/src/runtime/cgo/handle.go b/contrib/go/_std_1.19/src/runtime/cgo/handle.go
index d711900d79..d711900d79 100644
--- a/contrib/go/_std_1.18/src/runtime/cgo/handle.go
+++ b/contrib/go/_std_1.19/src/runtime/cgo/handle.go
diff --git a/contrib/go/_std_1.18/src/runtime/cgo/iscgo.go b/contrib/go/_std_1.19/src/runtime/cgo/iscgo.go
index e12d0f4b95..e12d0f4b95 100644
--- a/contrib/go/_std_1.18/src/runtime/cgo/iscgo.go
+++ b/contrib/go/_std_1.19/src/runtime/cgo/iscgo.go
diff --git a/contrib/go/_std_1.18/src/runtime/cgo/libcgo.h b/contrib/go/_std_1.19/src/runtime/cgo/libcgo.h
index af4960e7e9..af4960e7e9 100644
--- a/contrib/go/_std_1.18/src/runtime/cgo/libcgo.h
+++ b/contrib/go/_std_1.19/src/runtime/cgo/libcgo.h
diff --git a/contrib/go/_std_1.18/src/runtime/cgo/libcgo_unix.h b/contrib/go/_std_1.19/src/runtime/cgo/libcgo_unix.h
index a56a366f23..a56a366f23 100644
--- a/contrib/go/_std_1.18/src/runtime/cgo/libcgo_unix.h
+++ b/contrib/go/_std_1.19/src/runtime/cgo/libcgo_unix.h
diff --git a/contrib/go/_std_1.18/src/runtime/cgo/linux.go b/contrib/go/_std_1.19/src/runtime/cgo/linux.go
index 1d6fe03917..1d6fe03917 100644
--- a/contrib/go/_std_1.18/src/runtime/cgo/linux.go
+++ b/contrib/go/_std_1.19/src/runtime/cgo/linux.go
diff --git a/contrib/go/_std_1.18/src/runtime/cgo/linux_syscall.c b/contrib/go/_std_1.19/src/runtime/cgo/linux_syscall.c
index 59761c8b40..59761c8b40 100644
--- a/contrib/go/_std_1.18/src/runtime/cgo/linux_syscall.c
+++ b/contrib/go/_std_1.19/src/runtime/cgo/linux_syscall.c
diff --git a/contrib/go/_std_1.18/src/runtime/cgo/mmap.go b/contrib/go/_std_1.19/src/runtime/cgo/mmap.go
index eae0a9e7cc..eae0a9e7cc 100644
--- a/contrib/go/_std_1.18/src/runtime/cgo/mmap.go
+++ b/contrib/go/_std_1.19/src/runtime/cgo/mmap.go
diff --git a/contrib/go/_std_1.19/src/runtime/cgo/setenv.go b/contrib/go/_std_1.19/src/runtime/cgo/setenv.go
new file mode 100644
index 0000000000..2247cb2b59
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/cgo/setenv.go
@@ -0,0 +1,21 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix
+
+package cgo
+
+import _ "unsafe" // for go:linkname
+
+//go:cgo_import_static x_cgo_setenv
+//go:linkname x_cgo_setenv x_cgo_setenv
+//go:linkname _cgo_setenv runtime._cgo_setenv
+var x_cgo_setenv byte
+var _cgo_setenv = &x_cgo_setenv
+
+//go:cgo_import_static x_cgo_unsetenv
+//go:linkname x_cgo_unsetenv x_cgo_unsetenv
+//go:linkname _cgo_unsetenv runtime._cgo_unsetenv
+var x_cgo_unsetenv byte
+var _cgo_unsetenv = &x_cgo_unsetenv
diff --git a/contrib/go/_std_1.18/src/runtime/cgo/sigaction.go b/contrib/go/_std_1.19/src/runtime/cgo/sigaction.go
index dc714f7ef4..dc714f7ef4 100644
--- a/contrib/go/_std_1.18/src/runtime/cgo/sigaction.go
+++ b/contrib/go/_std_1.19/src/runtime/cgo/sigaction.go
diff --git a/contrib/go/_std_1.19/src/runtime/cgo_mmap.go b/contrib/go/_std_1.19/src/runtime/cgo_mmap.go
new file mode 100644
index 0000000000..4cb3e65f14
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/cgo_mmap.go
@@ -0,0 +1,70 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Support for memory sanitizer. See runtime/cgo/mmap.go.
+
+//go:build (linux && amd64) || (linux && arm64)
+
+package runtime
+
+import "unsafe"
+
+// _cgo_mmap is filled in by runtime/cgo when it is linked into the
+// program, so it is only non-nil when using cgo.
+//
+//go:linkname _cgo_mmap _cgo_mmap
+var _cgo_mmap unsafe.Pointer
+
+// _cgo_munmap is filled in by runtime/cgo when it is linked into the
+// program, so it is only non-nil when using cgo.
+//
+//go:linkname _cgo_munmap _cgo_munmap
+var _cgo_munmap unsafe.Pointer
+
+// mmap is used to route the mmap system call through C code when using cgo, to
+// support sanitizer interceptors. Don't allow stack splits, since this function
+// (used by sysAlloc) is called in a lot of low-level parts of the runtime and
+// callers often assume it won't acquire any locks.
+//
+//go:nosplit
+func mmap(addr unsafe.Pointer, n uintptr, prot, flags, fd int32, off uint32) (unsafe.Pointer, int) {
+	if _cgo_mmap != nil {
+		// Make ret a uintptr so that writing to it in the
+		// function literal does not trigger a write barrier.
+		// A write barrier here could break because of the way
+		// that mmap uses the same value both as a pointer and
+		// an errno value.
+		var ret uintptr
+		systemstack(func() {
+			ret = callCgoMmap(addr, n, prot, flags, fd, off)
+		})
+		if ret < 4096 {
+			return nil, int(ret)
+		}
+		return unsafe.Pointer(ret), 0
+	}
+	return sysMmap(addr, n, prot, flags, fd, off)
+}
+
+func munmap(addr unsafe.Pointer, n uintptr) {
+	if _cgo_munmap != nil {
+		systemstack(func() { callCgoMunmap(addr, n) })
+		return
+	}
+	sysMunmap(addr, n)
+}
+
+// sysMmap calls the mmap system call. It is implemented in assembly.
+func sysMmap(addr unsafe.Pointer, n uintptr, prot, flags, fd int32, off uint32) (p unsafe.Pointer, err int)
+
+// callCgoMmap calls the mmap function in the runtime/cgo package
+// using the GCC calling convention. It is implemented in assembly.
+func callCgoMmap(addr unsafe.Pointer, n uintptr, prot, flags, fd int32, off uint32) uintptr
+
+// sysMunmap calls the munmap system call. It is implemented in assembly.
+func sysMunmap(addr unsafe.Pointer, n uintptr)
+
+// callCgoMunmap calls the munmap function in the runtime/cgo package
+// using the GCC calling convention. It is implemented in assembly.
+func callCgoMunmap(addr unsafe.Pointer, n uintptr)
diff --git a/contrib/go/_std_1.19/src/runtime/cgo_sigaction.go b/contrib/go/_std_1.19/src/runtime/cgo_sigaction.go
new file mode 100644
index 0000000000..9500c52205
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/cgo_sigaction.go
@@ -0,0 +1,94 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Support for sanitizers. See runtime/cgo/sigaction.go.
+
+//go:build (linux && amd64) || (freebsd && amd64) || (linux && arm64) || (linux && ppc64le)
+
+package runtime
+
+import "unsafe"
+
+// _cgo_sigaction is filled in by runtime/cgo when it is linked into the
+// program, so it is only non-nil when using cgo.
+//
+//go:linkname _cgo_sigaction _cgo_sigaction
+var _cgo_sigaction unsafe.Pointer
+
+//go:nosplit
+//go:nowritebarrierrec
+func sigaction(sig uint32, new, old *sigactiont) {
+	// racewalk.go avoids adding sanitizing instrumentation to package runtime,
+	// but we might be calling into instrumented C functions here,
+	// so we need the pointer parameters to be properly marked.
+	//
+	// Mark the input as having been written before the call
+	// and the output as read after.
+	if msanenabled && new != nil {
+		msanwrite(unsafe.Pointer(new), unsafe.Sizeof(*new))
+	}
+	if asanenabled && new != nil {
+		asanwrite(unsafe.Pointer(new), unsafe.Sizeof(*new))
+	}
+	if _cgo_sigaction == nil || inForkedChild {
+		sysSigaction(sig, new, old)
+	} else {
+		// We need to call _cgo_sigaction, which means we need a big enough stack
+		// for C.  To complicate matters, we may be in libpreinit (before the
+		// runtime has been initialized) or in an asynchronous signal handler (with
+		// the current thread in transition between goroutines, or with the g0
+		// system stack already in use).
+
+		var ret int32
+
+		var g *g
+		if mainStarted {
+			g = getg()
+		}
+		sp := uintptr(unsafe.Pointer(&sig))
+		switch {
+		case g == nil:
+			// No g: we're on a C stack or a signal stack.
+			ret = callCgoSigaction(uintptr(sig), new, old)
+		case sp < g.stack.lo || sp >= g.stack.hi:
+			// We're no longer on g's stack, so we must be handling a signal.  It's
+			// possible that we interrupted the thread during a transition between g
+			// and g0, so we should stay on the current stack to avoid corrupting g0.
+			ret = callCgoSigaction(uintptr(sig), new, old)
+		default:
+			// We're running on g's stack, so either we're not in a signal handler or
+			// the signal handler has set the correct g.  If we're on gsignal or g0,
+			// systemstack will make the call directly; otherwise, it will switch to
+			// g0 to ensure we have enough room to call a libc function.
+			//
+			// The function literal that we pass to systemstack is not nosplit, but
+			// that's ok: we'll be running on a fresh, clean system stack so the stack
+			// check will always succeed anyway.
+			systemstack(func() {
+				ret = callCgoSigaction(uintptr(sig), new, old)
+			})
+		}
+
+		const EINVAL = 22
+		if ret == EINVAL {
+			// libc reserves certain signals — normally 32-33 — for pthreads, and
+			// returns EINVAL for sigaction calls on those signals.  If we get EINVAL,
+			// fall back to making the syscall directly.
+			sysSigaction(sig, new, old)
+		}
+	}
+
+	if msanenabled && old != nil {
+		msanread(unsafe.Pointer(old), unsafe.Sizeof(*old))
+	}
+	if asanenabled && old != nil {
+		asanread(unsafe.Pointer(old), unsafe.Sizeof(*old))
+	}
+}
+
+// callCgoSigaction calls the sigaction function in the runtime/cgo package
+// using the GCC calling convention. It is implemented in assembly.
+//
+//go:noescape
+func callCgoSigaction(sig uintptr, new, old *sigactiont) int32
diff --git a/contrib/go/_std_1.19/src/runtime/cgocall.go b/contrib/go/_std_1.19/src/runtime/cgocall.go
new file mode 100644
index 0000000000..892654ed5b
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/cgocall.go
@@ -0,0 +1,643 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Cgo call and callback support.
+//
+// To call into the C function f from Go, the cgo-generated code calls
+// runtime.cgocall(_cgo_Cfunc_f, frame), where _cgo_Cfunc_f is a
+// gcc-compiled function written by cgo.
+//
+// runtime.cgocall (below) calls entersyscall so as not to block
+// other goroutines or the garbage collector, and then calls
+// runtime.asmcgocall(_cgo_Cfunc_f, frame).
+//
+// runtime.asmcgocall (in asm_$GOARCH.s) switches to the m->g0 stack
+// (assumed to be an operating system-allocated stack, so safe to run
+// gcc-compiled code on) and calls _cgo_Cfunc_f(frame).
+//
+// _cgo_Cfunc_f invokes the actual C function f with arguments
+// taken from the frame structure, records the results in the frame,
+// and returns to runtime.asmcgocall.
+//
+// After it regains control, runtime.asmcgocall switches back to the
+// original g (m->curg)'s stack and returns to runtime.cgocall.
+//
+// After it regains control, runtime.cgocall calls exitsyscall, which blocks
+// until this m can run Go code without violating the $GOMAXPROCS limit,
+// and then unlocks g from m.
+//
+// The above description skipped over the possibility of the gcc-compiled
+// function f calling back into Go. If that happens, we continue down
+// the rabbit hole during the execution of f.
+//
+// To make it possible for gcc-compiled C code to call a Go function p.GoF,
+// cgo writes a gcc-compiled function named GoF (not p.GoF, since gcc doesn't
+// know about packages).  The gcc-compiled C function f calls GoF.
+//
+// GoF initializes "frame", a structure containing all of its
+// arguments and slots for p.GoF's results. It calls
+// crosscall2(_cgoexp_GoF, frame, framesize, ctxt) using the gcc ABI.
+//
+// crosscall2 (in cgo/asm_$GOARCH.s) is a four-argument adapter from
+// the gcc function call ABI to the gc function call ABI. At this
+// point we're in the Go runtime, but we're still running on m.g0's
+// stack and outside the $GOMAXPROCS limit. crosscall2 calls
+// runtime.cgocallback(_cgoexp_GoF, frame, ctxt) using the gc ABI.
+// (crosscall2's framesize argument is no longer used, but there's one
+// case where SWIG calls crosscall2 directly and expects to pass this
+// argument. See _cgo_panic.)
+//
+// runtime.cgocallback (in asm_$GOARCH.s) switches from m.g0's stack
+// to the original g (m.curg)'s stack, on which it calls
+// runtime.cgocallbackg(_cgoexp_GoF, frame, ctxt). As part of the
+// stack switch, runtime.cgocallback saves the current SP as
+// m.g0.sched.sp, so that any use of m.g0's stack during the execution
+// of the callback will be done below the existing stack frames.
+// Before overwriting m.g0.sched.sp, it pushes the old value on the
+// m.g0 stack, so that it can be restored later.
+//
+// runtime.cgocallbackg (below) is now running on a real goroutine
+// stack (not an m.g0 stack).  First it calls runtime.exitsyscall, which will
+// block until the $GOMAXPROCS limit allows running this goroutine.
+// Once exitsyscall has returned, it is safe to do things like call the memory
+// allocator or invoke the Go callback function.  runtime.cgocallbackg
+// first defers a function to unwind m.g0.sched.sp, so that if p.GoF
+// panics, m.g0.sched.sp will be restored to its old value: the m.g0 stack
+// and the m.curg stack will be unwound in lock step.
+// Then it calls _cgoexp_GoF(frame).
+//
+// _cgoexp_GoF, which was generated by cmd/cgo, unpacks the arguments
+// from frame, calls p.GoF, writes the results back to frame, and
+// returns. Now we start unwinding this whole process.
+//
+// runtime.cgocallbackg pops but does not execute the deferred
+// function to unwind m.g0.sched.sp, calls runtime.entersyscall, and
+// returns to runtime.cgocallback.
+//
+// After it regains control, runtime.cgocallback switches back to
+// m.g0's stack (the pointer is still in m.g0.sched.sp), restores the old
+// m.g0.sched.sp value from the stack, and returns to crosscall2.
+//
+// crosscall2 restores the callee-save registers for gcc and returns
+// to GoF, which unpacks any result values and returns to f.
+
+package runtime
+
+import (
+	"internal/goarch"
+	"runtime/internal/atomic"
+	"runtime/internal/sys"
+	"unsafe"
+)
+
+// Addresses collected in a cgo backtrace when crashing.
+// Length must match arg.Max in x_cgo_callers in runtime/cgo/gcc_traceback.c.
+type cgoCallers [32]uintptr
+
+// argset matches runtime/cgo/linux_syscall.c:argset_t
+type argset struct {
+	args   unsafe.Pointer
+	retval uintptr
+}
+
+// wrapper for syscall package to call cgocall for libc (cgo) calls.
+//
+//go:linkname syscall_cgocaller syscall.cgocaller
+//go:nosplit
+//go:uintptrescapes
+func syscall_cgocaller(fn unsafe.Pointer, args ...uintptr) uintptr {
+	as := argset{args: unsafe.Pointer(&args[0])}
+	cgocall(fn, unsafe.Pointer(&as))
+	return as.retval
+}
+
+var ncgocall uint64 // number of cgo calls in total for dead m
+
+// Call from Go to C.
+//
+// This must be nosplit because it's used for syscalls on some
+// platforms. Syscalls may have untyped arguments on the stack, so
+// it's not safe to grow or scan the stack.
+//
+//go:nosplit
+func cgocall(fn, arg unsafe.Pointer) int32 {
+	if !iscgo && GOOS != "solaris" && GOOS != "illumos" && GOOS != "windows" {
+		throw("cgocall unavailable")
+	}
+
+	if fn == nil {
+		throw("cgocall nil")
+	}
+
+	if raceenabled {
+		racereleasemerge(unsafe.Pointer(&racecgosync))
+	}
+
+	mp := getg().m
+	mp.ncgocall++
+	mp.ncgo++
+
+	// Reset traceback.
+	mp.cgoCallers[0] = 0
+
+	// Announce we are entering a system call
+	// so that the scheduler knows to create another
+	// M to run goroutines while we are in the
+	// foreign code.
+	//
+	// The call to asmcgocall is guaranteed not to
+	// grow the stack and does not allocate memory,
+	// so it is safe to call while "in a system call", outside
+	// the $GOMAXPROCS accounting.
+	//
+	// fn may call back into Go code, in which case we'll exit the
+	// "system call", run the Go code (which may grow the stack),
+	// and then re-enter the "system call" reusing the PC and SP
+	// saved by entersyscall here.
+	entersyscall()
+
+	// Tell asynchronous preemption that we're entering external
+	// code. We do this after entersyscall because this may block
+	// and cause an async preemption to fail, but at this point a
+	// sync preemption will succeed (though this is not a matter
+	// of correctness).
+	osPreemptExtEnter(mp)
+
+	mp.incgo = true
+	errno := asmcgocall(fn, arg)
+
+	// Update accounting before exitsyscall because exitsyscall may
+	// reschedule us on to a different M.
+	mp.incgo = false
+	mp.ncgo--
+
+	osPreemptExtExit(mp)
+
+	exitsyscall()
+
+	// Note that raceacquire must be called only after exitsyscall has
+	// wired this M to a P.
+	if raceenabled {
+		raceacquire(unsafe.Pointer(&racecgosync))
+	}
+
+	// From the garbage collector's perspective, time can move
+	// backwards in the sequence above. If there's a callback into
+	// Go code, GC will see this function at the call to
+	// asmcgocall. When the Go call later returns to C, the
+	// syscall PC/SP is rolled back and the GC sees this function
+	// back at the call to entersyscall. Normally, fn and arg
+	// would be live at entersyscall and dead at asmcgocall, so if
+	// time moved backwards, GC would see these arguments as dead
+	// and then live. Prevent these undead arguments from crashing
+	// GC by forcing them to stay live across this time warp.
+	KeepAlive(fn)
+	KeepAlive(arg)
+	KeepAlive(mp)
+
+	return errno
+}
+
+// Call from C back to Go. fn must point to an ABIInternal Go entry-point.
+//
+//go:nosplit
+func cgocallbackg(fn, frame unsafe.Pointer, ctxt uintptr) {
+	gp := getg()
+	if gp != gp.m.curg {
+		println("runtime: bad g in cgocallback")
+		exit(2)
+	}
+
+	// The call from C is on gp.m's g0 stack, so we must ensure
+	// that we stay on that M. We have to do this before calling
+	// exitsyscall, since it would otherwise be free to move us to
+	// a different M. The call to unlockOSThread is in unwindm.
+	lockOSThread()
+
+	checkm := gp.m
+
+	// Save current syscall parameters, so m.syscall can be
+	// used again if callback decide to make syscall.
+	syscall := gp.m.syscall
+
+	// entersyscall saves the caller's SP to allow the GC to trace the Go
+	// stack. However, since we're returning to an earlier stack frame and
+	// need to pair with the entersyscall() call made by cgocall, we must
+	// save syscall* and let reentersyscall restore them.
+	savedsp := unsafe.Pointer(gp.syscallsp)
+	savedpc := gp.syscallpc
+	exitsyscall() // coming out of cgo call
+	gp.m.incgo = false
+
+	osPreemptExtExit(gp.m)
+
+	cgocallbackg1(fn, frame, ctxt) // will call unlockOSThread
+
+	// At this point unlockOSThread has been called.
+	// The following code must not change to a different m.
+	// This is enforced by checking incgo in the schedule function.
+
+	gp.m.incgo = true
+
+	if gp.m != checkm {
+		throw("m changed unexpectedly in cgocallbackg")
+	}
+
+	osPreemptExtEnter(gp.m)
+
+	// going back to cgo call
+	reentersyscall(savedpc, uintptr(savedsp))
+
+	gp.m.syscall = syscall
+}
+
+func cgocallbackg1(fn, frame unsafe.Pointer, ctxt uintptr) {
+	gp := getg()
+
+	// When we return, undo the call to lockOSThread in cgocallbackg.
+	// We must still stay on the same m.
+	defer unlockOSThread()
+
+	if gp.m.needextram || atomic.Load(&extraMWaiters) > 0 {
+		gp.m.needextram = false
+		systemstack(newextram)
+	}
+
+	if ctxt != 0 {
+		s := append(gp.cgoCtxt, ctxt)
+
+		// Now we need to set gp.cgoCtxt = s, but we could get
+		// a SIGPROF signal while manipulating the slice, and
+		// the SIGPROF handler could pick up gp.cgoCtxt while
+		// tracing up the stack.  We need to ensure that the
+		// handler always sees a valid slice, so set the
+		// values in an order such that it always does.
+		p := (*slice)(unsafe.Pointer(&gp.cgoCtxt))
+		atomicstorep(unsafe.Pointer(&p.array), unsafe.Pointer(&s[0]))
+		p.cap = cap(s)
+		p.len = len(s)
+
+		defer func(gp *g) {
+			// Decrease the length of the slice by one, safely.
+			p := (*slice)(unsafe.Pointer(&gp.cgoCtxt))
+			p.len--
+		}(gp)
+	}
+
+	if gp.m.ncgo == 0 {
+		// The C call to Go came from a thread not currently running
+		// any Go. In the case of -buildmode=c-archive or c-shared,
+		// this call may be coming in before package initialization
+		// is complete. Wait until it is.
+		<-main_init_done
+	}
+
+	// Check whether the profiler needs to be turned on or off; this route to
+	// run Go code does not use runtime.execute, so bypasses the check there.
+	hz := sched.profilehz
+	if gp.m.profilehz != hz {
+		setThreadCPUProfiler(hz)
+	}
+
+	// Add entry to defer stack in case of panic.
+	restore := true
+	defer unwindm(&restore)
+
+	if raceenabled {
+		raceacquire(unsafe.Pointer(&racecgosync))
+	}
+
+	// Invoke callback. This function is generated by cmd/cgo and
+	// will unpack the argument frame and call the Go function.
+	var cb func(frame unsafe.Pointer)
+	cbFV := funcval{uintptr(fn)}
+	*(*unsafe.Pointer)(unsafe.Pointer(&cb)) = noescape(unsafe.Pointer(&cbFV))
+	cb(frame)
+
+	if raceenabled {
+		racereleasemerge(unsafe.Pointer(&racecgosync))
+	}
+
+	// Do not unwind m->g0->sched.sp.
+	// Our caller, cgocallback, will do that.
+	restore = false
+}
+
+func unwindm(restore *bool) {
+	if *restore {
+		// Restore sp saved by cgocallback during
+		// unwind of g's stack (see comment at top of file).
+		mp := acquirem()
+		sched := &mp.g0.sched
+		sched.sp = *(*uintptr)(unsafe.Pointer(sched.sp + alignUp(sys.MinFrameSize, sys.StackAlign)))
+
+		// Do the accounting that cgocall will not have a chance to do
+		// during an unwind.
+		//
+		// In the case where a Go call originates from C, ncgo is 0
+		// and there is no matching cgocall to end.
+		if mp.ncgo > 0 {
+			mp.incgo = false
+			mp.ncgo--
+			osPreemptExtExit(mp)
+		}
+
+		releasem(mp)
+	}
+}
+
+// called from assembly
+func badcgocallback() {
+	throw("misaligned stack in cgocallback")
+}
+
+// called from (incomplete) assembly
+func cgounimpl() {
+	throw("cgo not implemented")
+}
+
+var racecgosync uint64 // represents possible synchronization in C code
+
+// Pointer checking for cgo code.
+
+// We want to detect all cases where a program that does not use
+// unsafe makes a cgo call passing a Go pointer to memory that
+// contains a Go pointer. Here a Go pointer is defined as a pointer
+// to memory allocated by the Go runtime. Programs that use unsafe
+// can evade this restriction easily, so we don't try to catch them.
+// The cgo program will rewrite all possibly bad pointer arguments to
+// call cgoCheckPointer, where we can catch cases of a Go pointer
+// pointing to a Go pointer.
+
+// Complicating matters, taking the address of a slice or array
+// element permits the C program to access all elements of the slice
+// or array. In that case we will see a pointer to a single element,
+// but we need to check the entire data structure.
+
+// The cgoCheckPointer call takes additional arguments indicating that
+// it was called on an address expression. An additional argument of
+// true means that it only needs to check a single element. An
+// additional argument of a slice or array means that it needs to
+// check the entire slice/array, but nothing else. Otherwise, the
+// pointer could be anything, and we check the entire heap object,
+// which is conservative but safe.
+
+// When and if we implement a moving garbage collector,
+// cgoCheckPointer will pin the pointer for the duration of the cgo
+// call.  (This is necessary but not sufficient; the cgo program will
+// also have to change to pin Go pointers that cannot point to Go
+// pointers.)
+
+// cgoCheckPointer checks if the argument contains a Go pointer that
+// points to a Go pointer, and panics if it does.
+func cgoCheckPointer(ptr any, arg any) {
+	if debug.cgocheck == 0 {
+		return
+	}
+
+	ep := efaceOf(&ptr)
+	t := ep._type
+
+	top := true
+	if arg != nil && (t.kind&kindMask == kindPtr || t.kind&kindMask == kindUnsafePointer) {
+		p := ep.data
+		if t.kind&kindDirectIface == 0 {
+			p = *(*unsafe.Pointer)(p)
+		}
+		if p == nil || !cgoIsGoPointer(p) {
+			return
+		}
+		aep := efaceOf(&arg)
+		switch aep._type.kind & kindMask {
+		case kindBool:
+			if t.kind&kindMask == kindUnsafePointer {
+				// We don't know the type of the element.
+				break
+			}
+			pt := (*ptrtype)(unsafe.Pointer(t))
+			cgoCheckArg(pt.elem, p, true, false, cgoCheckPointerFail)
+			return
+		case kindSlice:
+			// Check the slice rather than the pointer.
+			ep = aep
+			t = ep._type
+		case kindArray:
+			// Check the array rather than the pointer.
+			// Pass top as false since we have a pointer
+			// to the array.
+			ep = aep
+			t = ep._type
+			top = false
+		default:
+			throw("can't happen")
+		}
+	}
+
+	cgoCheckArg(t, ep.data, t.kind&kindDirectIface == 0, top, cgoCheckPointerFail)
+}
+
+const cgoCheckPointerFail = "cgo argument has Go pointer to Go pointer"
+const cgoResultFail = "cgo result has Go pointer"
+
+// cgoCheckArg is the real work of cgoCheckPointer. The argument p
+// is either a pointer to the value (of type t), or the value itself,
+// depending on indir. The top parameter is whether we are at the top
+// level, where Go pointers are allowed.
+func cgoCheckArg(t *_type, p unsafe.Pointer, indir, top bool, msg string) {
+	if t.ptrdata == 0 || p == nil {
+		// If the type has no pointers there is nothing to do.
+		return
+	}
+
+	switch t.kind & kindMask {
+	default:
+		throw("can't happen")
+	case kindArray:
+		at := (*arraytype)(unsafe.Pointer(t))
+		if !indir {
+			if at.len != 1 {
+				throw("can't happen")
+			}
+			cgoCheckArg(at.elem, p, at.elem.kind&kindDirectIface == 0, top, msg)
+			return
+		}
+		for i := uintptr(0); i < at.len; i++ {
+			cgoCheckArg(at.elem, p, true, top, msg)
+			p = add(p, at.elem.size)
+		}
+	case kindChan, kindMap:
+		// These types contain internal pointers that will
+		// always be allocated in the Go heap. It's never OK
+		// to pass them to C.
+		panic(errorString(msg))
+	case kindFunc:
+		if indir {
+			p = *(*unsafe.Pointer)(p)
+		}
+		if !cgoIsGoPointer(p) {
+			return
+		}
+		panic(errorString(msg))
+	case kindInterface:
+		it := *(**_type)(p)
+		if it == nil {
+			return
+		}
+		// A type known at compile time is OK since it's
+		// constant. A type not known at compile time will be
+		// in the heap and will not be OK.
+		if inheap(uintptr(unsafe.Pointer(it))) {
+			panic(errorString(msg))
+		}
+		p = *(*unsafe.Pointer)(add(p, goarch.PtrSize))
+		if !cgoIsGoPointer(p) {
+			return
+		}
+		if !top {
+			panic(errorString(msg))
+		}
+		cgoCheckArg(it, p, it.kind&kindDirectIface == 0, false, msg)
+	case kindSlice:
+		st := (*slicetype)(unsafe.Pointer(t))
+		s := (*slice)(p)
+		p = s.array
+		if p == nil || !cgoIsGoPointer(p) {
+			return
+		}
+		if !top {
+			panic(errorString(msg))
+		}
+		if st.elem.ptrdata == 0 {
+			return
+		}
+		for i := 0; i < s.cap; i++ {
+			cgoCheckArg(st.elem, p, true, false, msg)
+			p = add(p, st.elem.size)
+		}
+	case kindString:
+		ss := (*stringStruct)(p)
+		if !cgoIsGoPointer(ss.str) {
+			return
+		}
+		if !top {
+			panic(errorString(msg))
+		}
+	case kindStruct:
+		st := (*structtype)(unsafe.Pointer(t))
+		if !indir {
+			if len(st.fields) != 1 {
+				throw("can't happen")
+			}
+			cgoCheckArg(st.fields[0].typ, p, st.fields[0].typ.kind&kindDirectIface == 0, top, msg)
+			return
+		}
+		for _, f := range st.fields {
+			if f.typ.ptrdata == 0 {
+				continue
+			}
+			cgoCheckArg(f.typ, add(p, f.offset), true, top, msg)
+		}
+	case kindPtr, kindUnsafePointer:
+		if indir {
+			p = *(*unsafe.Pointer)(p)
+			if p == nil {
+				return
+			}
+		}
+
+		if !cgoIsGoPointer(p) {
+			return
+		}
+		if !top {
+			panic(errorString(msg))
+		}
+
+		cgoCheckUnknownPointer(p, msg)
+	}
+}
+
+// cgoCheckUnknownPointer is called for an arbitrary pointer into Go
+// memory. It checks whether that Go memory contains any other
+// pointer into Go memory. If it does, we panic.
+// The return values are unused but useful to see in panic tracebacks.
+func cgoCheckUnknownPointer(p unsafe.Pointer, msg string) (base, i uintptr) {
+	if inheap(uintptr(p)) {
+		b, span, _ := findObject(uintptr(p), 0, 0)
+		base = b
+		if base == 0 {
+			return
+		}
+		hbits := heapBitsForAddr(base)
+		n := span.elemsize
+		for i = uintptr(0); i < n; i += goarch.PtrSize {
+			if !hbits.morePointers() {
+				// No more possible pointers.
+				break
+			}
+			if hbits.isPointer() && cgoIsGoPointer(*(*unsafe.Pointer)(unsafe.Pointer(base + i))) {
+				panic(errorString(msg))
+			}
+			hbits = hbits.next()
+		}
+
+		return
+	}
+
+	for _, datap := range activeModules() {
+		if cgoInRange(p, datap.data, datap.edata) || cgoInRange(p, datap.bss, datap.ebss) {
+			// We have no way to know the size of the object.
+			// We have to assume that it might contain a pointer.
+			panic(errorString(msg))
+		}
+		// In the text or noptr sections, we know that the
+		// pointer does not point to a Go pointer.
+	}
+
+	return
+}
+
+// cgoIsGoPointer reports whether the pointer is a Go pointer--a
+// pointer to Go memory. We only care about Go memory that might
+// contain pointers.
+//
+//go:nosplit
+//go:nowritebarrierrec
+func cgoIsGoPointer(p unsafe.Pointer) bool {
+	if p == nil {
+		return false
+	}
+
+	if inHeapOrStack(uintptr(p)) {
+		return true
+	}
+
+	for _, datap := range activeModules() {
+		if cgoInRange(p, datap.data, datap.edata) || cgoInRange(p, datap.bss, datap.ebss) {
+			return true
+		}
+	}
+
+	return false
+}
+
+// cgoInRange reports whether p is between start and end.
+//
+//go:nosplit
+//go:nowritebarrierrec
+func cgoInRange(p unsafe.Pointer, start, end uintptr) bool {
+	return start <= uintptr(p) && uintptr(p) < end
+}
+
+// cgoCheckResult is called to check the result parameter of an
+// exported Go function. It panics if the result is or contains a Go
+// pointer.
+func cgoCheckResult(val any) {
+	if debug.cgocheck == 0 {
+		return
+	}
+
+	ep := efaceOf(&val)
+	t := ep._type
+	cgoCheckArg(t, ep.data, t.kind&kindDirectIface == 0, false, cgoResultFail)
+}
diff --git a/contrib/go/_std_1.18/src/runtime/cgocallback.go b/contrib/go/_std_1.19/src/runtime/cgocallback.go
index 59953f1cee..59953f1cee 100644
--- a/contrib/go/_std_1.18/src/runtime/cgocallback.go
+++ b/contrib/go/_std_1.19/src/runtime/cgocallback.go
diff --git a/contrib/go/_std_1.19/src/runtime/cgocheck.go b/contrib/go/_std_1.19/src/runtime/cgocheck.go
new file mode 100644
index 0000000000..74a2ec09bc
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/cgocheck.go
@@ -0,0 +1,268 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Code to check that pointer writes follow the cgo rules.
+// These functions are invoked via the write barrier when debug.cgocheck > 1.
+
+package runtime
+
+import (
+	"internal/goarch"
+	"unsafe"
+)
+
+const cgoWriteBarrierFail = "Go pointer stored into non-Go memory"
+
+// cgoCheckWriteBarrier is called whenever a pointer is stored into memory.
+// It throws if the program is storing a Go pointer into non-Go memory.
+//
+// This is called from the write barrier, so its entire call tree must
+// be nosplit.
+//
+//go:nosplit
+//go:nowritebarrier
+func cgoCheckWriteBarrier(dst *uintptr, src uintptr) {
+	if !cgoIsGoPointer(unsafe.Pointer(src)) {
+		return
+	}
+	if cgoIsGoPointer(unsafe.Pointer(dst)) {
+		return
+	}
+
+	// If we are running on the system stack then dst might be an
+	// address on the stack, which is OK.
+	g := getg()
+	if g == g.m.g0 || g == g.m.gsignal {
+		return
+	}
+
+	// Allocating memory can write to various mfixalloc structs
+	// that look like they are non-Go memory.
+	if g.m.mallocing != 0 {
+		return
+	}
+
+	// It's OK if writing to memory allocated by persistentalloc.
+	// Do this check last because it is more expensive and rarely true.
+	// If it is false the expense doesn't matter since we are crashing.
+	if inPersistentAlloc(uintptr(unsafe.Pointer(dst))) {
+		return
+	}
+
+	systemstack(func() {
+		println("write of Go pointer", hex(src), "to non-Go memory", hex(uintptr(unsafe.Pointer(dst))))
+		throw(cgoWriteBarrierFail)
+	})
+}
+
+// cgoCheckMemmove is called when moving a block of memory.
+// dst and src point off bytes into the value to copy.
+// size is the number of bytes to copy.
+// It throws if the program is copying a block that contains a Go pointer
+// into non-Go memory.
+//
+//go:nosplit
+//go:nowritebarrier
+func cgoCheckMemmove(typ *_type, dst, src unsafe.Pointer, off, size uintptr) {
+	if typ.ptrdata == 0 {
+		return
+	}
+	if !cgoIsGoPointer(src) {
+		return
+	}
+	if cgoIsGoPointer(dst) {
+		return
+	}
+	cgoCheckTypedBlock(typ, src, off, size)
+}
+
+// cgoCheckSliceCopy is called when copying n elements of a slice.
+// src and dst are pointers to the first element of the slice.
+// typ is the element type of the slice.
+// It throws if the program is copying slice elements that contain Go pointers
+// into non-Go memory.
+//
+//go:nosplit
+//go:nowritebarrier
+func cgoCheckSliceCopy(typ *_type, dst, src unsafe.Pointer, n int) {
+	if typ.ptrdata == 0 {
+		return
+	}
+	if !cgoIsGoPointer(src) {
+		return
+	}
+	if cgoIsGoPointer(dst) {
+		return
+	}
+	p := src
+	for i := 0; i < n; i++ {
+		cgoCheckTypedBlock(typ, p, 0, typ.size)
+		p = add(p, typ.size)
+	}
+}
+
+// cgoCheckTypedBlock checks the block of memory at src, for up to size bytes,
+// and throws if it finds a Go pointer. The type of the memory is typ,
+// and src is off bytes into that type.
+//
+//go:nosplit
+//go:nowritebarrier
+func cgoCheckTypedBlock(typ *_type, src unsafe.Pointer, off, size uintptr) {
+	// Anything past typ.ptrdata is not a pointer.
+	if typ.ptrdata <= off {
+		return
+	}
+	if ptrdataSize := typ.ptrdata - off; size > ptrdataSize {
+		size = ptrdataSize
+	}
+
+	if typ.kind&kindGCProg == 0 {
+		cgoCheckBits(src, typ.gcdata, off, size)
+		return
+	}
+
+	// The type has a GC program. Try to find GC bits somewhere else.
+	for _, datap := range activeModules() {
+		if cgoInRange(src, datap.data, datap.edata) {
+			doff := uintptr(src) - datap.data
+			cgoCheckBits(add(src, -doff), datap.gcdatamask.bytedata, off+doff, size)
+			return
+		}
+		if cgoInRange(src, datap.bss, datap.ebss) {
+			boff := uintptr(src) - datap.bss
+			cgoCheckBits(add(src, -boff), datap.gcbssmask.bytedata, off+boff, size)
+			return
+		}
+	}
+
+	s := spanOfUnchecked(uintptr(src))
+	if s.state.get() == mSpanManual {
+		// There are no heap bits for value stored on the stack.
+		// For a channel receive src might be on the stack of some
+		// other goroutine, so we can't unwind the stack even if
+		// we wanted to.
+		// We can't expand the GC program without extra storage
+		// space we can't easily get.
+		// Fortunately we have the type information.
+		systemstack(func() {
+			cgoCheckUsingType(typ, src, off, size)
+		})
+		return
+	}
+
+	// src must be in the regular heap.
+
+	hbits := heapBitsForAddr(uintptr(src))
+	for i := uintptr(0); i < off+size; i += goarch.PtrSize {
+		bits := hbits.bits()
+		if i >= off && bits&bitPointer != 0 {
+			v := *(*unsafe.Pointer)(add(src, i))
+			if cgoIsGoPointer(v) {
+				throw(cgoWriteBarrierFail)
+			}
+		}
+		hbits = hbits.next()
+	}
+}
+
+// cgoCheckBits checks the block of memory at src, for up to size
+// bytes, and throws if it finds a Go pointer. The gcbits mark each
+// pointer value. The src pointer is off bytes into the gcbits.
+//
+//go:nosplit
+//go:nowritebarrier
+func cgoCheckBits(src unsafe.Pointer, gcbits *byte, off, size uintptr) {
+	skipMask := off / goarch.PtrSize / 8
+	skipBytes := skipMask * goarch.PtrSize * 8
+	ptrmask := addb(gcbits, skipMask)
+	src = add(src, skipBytes)
+	off -= skipBytes
+	size += off
+	var bits uint32
+	for i := uintptr(0); i < size; i += goarch.PtrSize {
+		if i&(goarch.PtrSize*8-1) == 0 {
+			bits = uint32(*ptrmask)
+			ptrmask = addb(ptrmask, 1)
+		} else {
+			bits >>= 1
+		}
+		if off > 0 {
+			off -= goarch.PtrSize
+		} else {
+			if bits&1 != 0 {
+				v := *(*unsafe.Pointer)(add(src, i))
+				if cgoIsGoPointer(v) {
+					throw(cgoWriteBarrierFail)
+				}
+			}
+		}
+	}
+}
+
+// cgoCheckUsingType is like cgoCheckTypedBlock, but is a last ditch
+// fall back to look for pointers in src using the type information.
+// We only use this when looking at a value on the stack when the type
+// uses a GC program, because otherwise it's more efficient to use the
+// GC bits. This is called on the system stack.
+//
+//go:nowritebarrier
+//go:systemstack
+func cgoCheckUsingType(typ *_type, src unsafe.Pointer, off, size uintptr) {
+	if typ.ptrdata == 0 {
+		return
+	}
+
+	// Anything past typ.ptrdata is not a pointer.
+	if typ.ptrdata <= off {
+		return
+	}
+	if ptrdataSize := typ.ptrdata - off; size > ptrdataSize {
+		size = ptrdataSize
+	}
+
+	if typ.kind&kindGCProg == 0 {
+		cgoCheckBits(src, typ.gcdata, off, size)
+		return
+	}
+	switch typ.kind & kindMask {
+	default:
+		throw("can't happen")
+	case kindArray:
+		at := (*arraytype)(unsafe.Pointer(typ))
+		for i := uintptr(0); i < at.len; i++ {
+			if off < at.elem.size {
+				cgoCheckUsingType(at.elem, src, off, size)
+			}
+			src = add(src, at.elem.size)
+			skipped := off
+			if skipped > at.elem.size {
+				skipped = at.elem.size
+			}
+			checked := at.elem.size - skipped
+			off -= skipped
+			if size <= checked {
+				return
+			}
+			size -= checked
+		}
+	case kindStruct:
+		st := (*structtype)(unsafe.Pointer(typ))
+		for _, f := range st.fields {
+			if off < f.typ.size {
+				cgoCheckUsingType(f.typ, src, off, size)
+			}
+			src = add(src, f.typ.size)
+			skipped := off
+			if skipped > f.typ.size {
+				skipped = f.typ.size
+			}
+			checked := f.typ.size - skipped
+			off -= skipped
+			if size <= checked {
+				return
+			}
+			size -= checked
+		}
+	}
+}
diff --git a/contrib/go/_std_1.19/src/runtime/chan.go b/contrib/go/_std_1.19/src/runtime/chan.go
new file mode 100644
index 0000000000..ca516ad9e8
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/chan.go
@@ -0,0 +1,851 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+// This file contains the implementation of Go channels.
+
+// Invariants:
+//  At least one of c.sendq and c.recvq is empty,
+//  except for the case of an unbuffered channel with a single goroutine
+//  blocked on it for both sending and receiving using a select statement,
+//  in which case the length of c.sendq and c.recvq is limited only by the
+//  size of the select statement.
+//
+// For buffered channels, also:
+//  c.qcount > 0 implies that c.recvq is empty.
+//  c.qcount < c.dataqsiz implies that c.sendq is empty.
+
+import (
+	"internal/abi"
+	"runtime/internal/atomic"
+	"runtime/internal/math"
+	"unsafe"
+)
+
+const (
+	maxAlign  = 8
+	hchanSize = unsafe.Sizeof(hchan{}) + uintptr(-int(unsafe.Sizeof(hchan{}))&(maxAlign-1))
+	debugChan = false
+)
+
+type hchan struct {
+	qcount   uint           // total data in the queue
+	dataqsiz uint           // size of the circular queue
+	buf      unsafe.Pointer // points to an array of dataqsiz elements
+	elemsize uint16
+	closed   uint32
+	elemtype *_type // element type
+	sendx    uint   // send index
+	recvx    uint   // receive index
+	recvq    waitq  // list of recv waiters
+	sendq    waitq  // list of send waiters
+
+	// lock protects all fields in hchan, as well as several
+	// fields in sudogs blocked on this channel.
+	//
+	// Do not change another G's status while holding this lock
+	// (in particular, do not ready a G), as this can deadlock
+	// with stack shrinking.
+	lock mutex
+}
+
+type waitq struct {
+	first *sudog
+	last  *sudog
+}
+
+//go:linkname reflect_makechan reflect.makechan
+func reflect_makechan(t *chantype, size int) *hchan {
+	return makechan(t, size)
+}
+
+func makechan64(t *chantype, size int64) *hchan {
+	if int64(int(size)) != size {
+		panic(plainError("makechan: size out of range"))
+	}
+
+	return makechan(t, int(size))
+}
+
+func makechan(t *chantype, size int) *hchan {
+	elem := t.elem
+
+	// compiler checks this but be safe.
+	if elem.size >= 1<<16 {
+		throw("makechan: invalid channel element type")
+	}
+	if hchanSize%maxAlign != 0 || elem.align > maxAlign {
+		throw("makechan: bad alignment")
+	}
+
+	mem, overflow := math.MulUintptr(elem.size, uintptr(size))
+	if overflow || mem > maxAlloc-hchanSize || size < 0 {
+		panic(plainError("makechan: size out of range"))
+	}
+
+	// Hchan does not contain pointers interesting for GC when elements stored in buf do not contain pointers.
+	// buf points into the same allocation, elemtype is persistent.
+	// SudoG's are referenced from their owning thread so they can't be collected.
+	// TODO(dvyukov,rlh): Rethink when collector can move allocated objects.
+	var c *hchan
+	switch {
+	case mem == 0:
+		// Queue or element size is zero.
+		c = (*hchan)(mallocgc(hchanSize, nil, true))
+		// Race detector uses this location for synchronization.
+		c.buf = c.raceaddr()
+	case elem.ptrdata == 0:
+		// Elements do not contain pointers.
+		// Allocate hchan and buf in one call.
+		c = (*hchan)(mallocgc(hchanSize+mem, nil, true))
+		c.buf = add(unsafe.Pointer(c), hchanSize)
+	default:
+		// Elements contain pointers.
+		c = new(hchan)
+		c.buf = mallocgc(mem, elem, true)
+	}
+
+	c.elemsize = uint16(elem.size)
+	c.elemtype = elem
+	c.dataqsiz = uint(size)
+	lockInit(&c.lock, lockRankHchan)
+
+	if debugChan {
+		print("makechan: chan=", c, "; elemsize=", elem.size, "; dataqsiz=", size, "\n")
+	}
+	return c
+}
+
+// chanbuf(c, i) is pointer to the i'th slot in the buffer.
+func chanbuf(c *hchan, i uint) unsafe.Pointer {
+	return add(c.buf, uintptr(i)*uintptr(c.elemsize))
+}
+
+// full reports whether a send on c would block (that is, the channel is full).
+// It uses a single word-sized read of mutable state, so although
+// the answer is instantaneously true, the correct answer may have changed
+// by the time the calling function receives the return value.
+func full(c *hchan) bool {
+	// c.dataqsiz is immutable (never written after the channel is created)
+	// so it is safe to read at any time during channel operation.
+	if c.dataqsiz == 0 {
+		// Assumes that a pointer read is relaxed-atomic.
+		return c.recvq.first == nil
+	}
+	// Assumes that a uint read is relaxed-atomic.
+	return c.qcount == c.dataqsiz
+}
+
+// entry point for c <- x from compiled code
+//
+//go:nosplit
+func chansend1(c *hchan, elem unsafe.Pointer) {
+	chansend(c, elem, true, getcallerpc())
+}
+
+/*
+ * generic single channel send/recv
+ * If block is not nil,
+ * then the protocol will not
+ * sleep but return if it could
+ * not complete.
+ *
+ * sleep can wake up with g.param == nil
+ * when a channel involved in the sleep has
+ * been closed.  it is easiest to loop and re-run
+ * the operation; we'll see that it's now closed.
+ */
+func chansend(c *hchan, ep unsafe.Pointer, block bool, callerpc uintptr) bool {
+	if c == nil {
+		if !block {
+			return false
+		}
+		gopark(nil, nil, waitReasonChanSendNilChan, traceEvGoStop, 2)
+		throw("unreachable")
+	}
+
+	if debugChan {
+		print("chansend: chan=", c, "\n")
+	}
+
+	if raceenabled {
+		racereadpc(c.raceaddr(), callerpc, abi.FuncPCABIInternal(chansend))
+	}
+
+	// Fast path: check for failed non-blocking operation without acquiring the lock.
+	//
+	// After observing that the channel is not closed, we observe that the channel is
+	// not ready for sending. Each of these observations is a single word-sized read
+	// (first c.closed and second full()).
+	// Because a closed channel cannot transition from 'ready for sending' to
+	// 'not ready for sending', even if the channel is closed between the two observations,
+	// they imply a moment between the two when the channel was both not yet closed
+	// and not ready for sending. We behave as if we observed the channel at that moment,
+	// and report that the send cannot proceed.
+	//
+	// It is okay if the reads are reordered here: if we observe that the channel is not
+	// ready for sending and then observe that it is not closed, that implies that the
+	// channel wasn't closed during the first observation. However, nothing here
+	// guarantees forward progress. We rely on the side effects of lock release in
+	// chanrecv() and closechan() to update this thread's view of c.closed and full().
+	if !block && c.closed == 0 && full(c) {
+		return false
+	}
+
+	var t0 int64
+	if blockprofilerate > 0 {
+		t0 = cputicks()
+	}
+
+	lock(&c.lock)
+
+	if c.closed != 0 {
+		unlock(&c.lock)
+		panic(plainError("send on closed channel"))
+	}
+
+	if sg := c.recvq.dequeue(); sg != nil {
+		// Found a waiting receiver. We pass the value we want to send
+		// directly to the receiver, bypassing the channel buffer (if any).
+		send(c, sg, ep, func() { unlock(&c.lock) }, 3)
+		return true
+	}
+
+	if c.qcount < c.dataqsiz {
+		// Space is available in the channel buffer. Enqueue the element to send.
+		qp := chanbuf(c, c.sendx)
+		if raceenabled {
+			racenotify(c, c.sendx, nil)
+		}
+		typedmemmove(c.elemtype, qp, ep)
+		c.sendx++
+		if c.sendx == c.dataqsiz {
+			c.sendx = 0
+		}
+		c.qcount++
+		unlock(&c.lock)
+		return true
+	}
+
+	if !block {
+		unlock(&c.lock)
+		return false
+	}
+
+	// Block on the channel. Some receiver will complete our operation for us.
+	gp := getg()
+	mysg := acquireSudog()
+	mysg.releasetime = 0
+	if t0 != 0 {
+		mysg.releasetime = -1
+	}
+	// No stack splits between assigning elem and enqueuing mysg
+	// on gp.waiting where copystack can find it.
+	mysg.elem = ep
+	mysg.waitlink = nil
+	mysg.g = gp
+	mysg.isSelect = false
+	mysg.c = c
+	gp.waiting = mysg
+	gp.param = nil
+	c.sendq.enqueue(mysg)
+	// Signal to anyone trying to shrink our stack that we're about
+	// to park on a channel. The window between when this G's status
+	// changes and when we set gp.activeStackChans is not safe for
+	// stack shrinking.
+	atomic.Store8(&gp.parkingOnChan, 1)
+	gopark(chanparkcommit, unsafe.Pointer(&c.lock), waitReasonChanSend, traceEvGoBlockSend, 2)
+	// Ensure the value being sent is kept alive until the
+	// receiver copies it out. The sudog has a pointer to the
+	// stack object, but sudogs aren't considered as roots of the
+	// stack tracer.
+	KeepAlive(ep)
+
+	// someone woke us up.
+	if mysg != gp.waiting {
+		throw("G waiting list is corrupted")
+	}
+	gp.waiting = nil
+	gp.activeStackChans = false
+	closed := !mysg.success
+	gp.param = nil
+	if mysg.releasetime > 0 {
+		blockevent(mysg.releasetime-t0, 2)
+	}
+	mysg.c = nil
+	releaseSudog(mysg)
+	if closed {
+		if c.closed == 0 {
+			throw("chansend: spurious wakeup")
+		}
+		panic(plainError("send on closed channel"))
+	}
+	return true
+}
+
+// send processes a send operation on an empty channel c.
+// The value ep sent by the sender is copied to the receiver sg.
+// The receiver is then woken up to go on its merry way.
+// Channel c must be empty and locked.  send unlocks c with unlockf.
+// sg must already be dequeued from c.
+// ep must be non-nil and point to the heap or the caller's stack.
+func send(c *hchan, sg *sudog, ep unsafe.Pointer, unlockf func(), skip int) {
+	if raceenabled {
+		if c.dataqsiz == 0 {
+			racesync(c, sg)
+		} else {
+			// Pretend we go through the buffer, even though
+			// we copy directly. Note that we need to increment
+			// the head/tail locations only when raceenabled.
+			racenotify(c, c.recvx, nil)
+			racenotify(c, c.recvx, sg)
+			c.recvx++
+			if c.recvx == c.dataqsiz {
+				c.recvx = 0
+			}
+			c.sendx = c.recvx // c.sendx = (c.sendx+1) % c.dataqsiz
+		}
+	}
+	if sg.elem != nil {
+		sendDirect(c.elemtype, sg, ep)
+		sg.elem = nil
+	}
+	gp := sg.g
+	unlockf()
+	gp.param = unsafe.Pointer(sg)
+	sg.success = true
+	if sg.releasetime != 0 {
+		sg.releasetime = cputicks()
+	}
+	goready(gp, skip+1)
+}
+
+// Sends and receives on unbuffered or empty-buffered channels are the
+// only operations where one running goroutine writes to the stack of
+// another running goroutine. The GC assumes that stack writes only
+// happen when the goroutine is running and are only done by that
+// goroutine. Using a write barrier is sufficient to make up for
+// violating that assumption, but the write barrier has to work.
+// typedmemmove will call bulkBarrierPreWrite, but the target bytes
+// are not in the heap, so that will not help. We arrange to call
+// memmove and typeBitsBulkBarrier instead.
+
+func sendDirect(t *_type, sg *sudog, src unsafe.Pointer) {
+	// src is on our stack, dst is a slot on another stack.
+
+	// Once we read sg.elem out of sg, it will no longer
+	// be updated if the destination's stack gets copied (shrunk).
+	// So make sure that no preemption points can happen between read & use.
+	dst := sg.elem
+	typeBitsBulkBarrier(t, uintptr(dst), uintptr(src), t.size)
+	// No need for cgo write barrier checks because dst is always
+	// Go memory.
+	memmove(dst, src, t.size)
+}
+
+func recvDirect(t *_type, sg *sudog, dst unsafe.Pointer) {
+	// dst is on our stack or the heap, src is on another stack.
+	// The channel is locked, so src will not move during this
+	// operation.
+	src := sg.elem
+	typeBitsBulkBarrier(t, uintptr(dst), uintptr(src), t.size)
+	memmove(dst, src, t.size)
+}
+
+func closechan(c *hchan) {
+	if c == nil {
+		panic(plainError("close of nil channel"))
+	}
+
+	lock(&c.lock)
+	if c.closed != 0 {
+		unlock(&c.lock)
+		panic(plainError("close of closed channel"))
+	}
+
+	if raceenabled {
+		callerpc := getcallerpc()
+		racewritepc(c.raceaddr(), callerpc, abi.FuncPCABIInternal(closechan))
+		racerelease(c.raceaddr())
+	}
+
+	c.closed = 1
+
+	var glist gList
+
+	// release all readers
+	for {
+		sg := c.recvq.dequeue()
+		if sg == nil {
+			break
+		}
+		if sg.elem != nil {
+			typedmemclr(c.elemtype, sg.elem)
+			sg.elem = nil
+		}
+		if sg.releasetime != 0 {
+			sg.releasetime = cputicks()
+		}
+		gp := sg.g
+		gp.param = unsafe.Pointer(sg)
+		sg.success = false
+		if raceenabled {
+			raceacquireg(gp, c.raceaddr())
+		}
+		glist.push(gp)
+	}
+
+	// release all writers (they will panic)
+	for {
+		sg := c.sendq.dequeue()
+		if sg == nil {
+			break
+		}
+		sg.elem = nil
+		if sg.releasetime != 0 {
+			sg.releasetime = cputicks()
+		}
+		gp := sg.g
+		gp.param = unsafe.Pointer(sg)
+		sg.success = false
+		if raceenabled {
+			raceacquireg(gp, c.raceaddr())
+		}
+		glist.push(gp)
+	}
+	unlock(&c.lock)
+
+	// Ready all Gs now that we've dropped the channel lock.
+	for !glist.empty() {
+		gp := glist.pop()
+		gp.schedlink = 0
+		goready(gp, 3)
+	}
+}
+
+// empty reports whether a read from c would block (that is, the channel is
+// empty).  It uses a single atomic read of mutable state.
+func empty(c *hchan) bool {
+	// c.dataqsiz is immutable.
+	if c.dataqsiz == 0 {
+		return atomic.Loadp(unsafe.Pointer(&c.sendq.first)) == nil
+	}
+	return atomic.Loaduint(&c.qcount) == 0
+}
+
+// entry points for <- c from compiled code
+//
+//go:nosplit
+func chanrecv1(c *hchan, elem unsafe.Pointer) {
+	chanrecv(c, elem, true)
+}
+
+//go:nosplit
+func chanrecv2(c *hchan, elem unsafe.Pointer) (received bool) {
+	_, received = chanrecv(c, elem, true)
+	return
+}
+
+// chanrecv receives on channel c and writes the received data to ep.
+// ep may be nil, in which case received data is ignored.
+// If block == false and no elements are available, returns (false, false).
+// Otherwise, if c is closed, zeros *ep and returns (true, false).
+// Otherwise, fills in *ep with an element and returns (true, true).
+// A non-nil ep must point to the heap or the caller's stack.
+func chanrecv(c *hchan, ep unsafe.Pointer, block bool) (selected, received bool) {
+	// raceenabled: don't need to check ep, as it is always on the stack
+	// or is new memory allocated by reflect.
+
+	if debugChan {
+		print("chanrecv: chan=", c, "\n")
+	}
+
+	if c == nil {
+		if !block {
+			return
+		}
+		gopark(nil, nil, waitReasonChanReceiveNilChan, traceEvGoStop, 2)
+		throw("unreachable")
+	}
+
+	// Fast path: check for failed non-blocking operation without acquiring the lock.
+	if !block && empty(c) {
+		// After observing that the channel is not ready for receiving, we observe whether the
+		// channel is closed.
+		//
+		// Reordering of these checks could lead to incorrect behavior when racing with a close.
+		// For example, if the channel was open and not empty, was closed, and then drained,
+		// reordered reads could incorrectly indicate "open and empty". To prevent reordering,
+		// we use atomic loads for both checks, and rely on emptying and closing to happen in
+		// separate critical sections under the same lock.  This assumption fails when closing
+		// an unbuffered channel with a blocked send, but that is an error condition anyway.
+		if atomic.Load(&c.closed) == 0 {
+			// Because a channel cannot be reopened, the later observation of the channel
+			// being not closed implies that it was also not closed at the moment of the
+			// first observation. We behave as if we observed the channel at that moment
+			// and report that the receive cannot proceed.
+			return
+		}
+		// The channel is irreversibly closed. Re-check whether the channel has any pending data
+		// to receive, which could have arrived between the empty and closed checks above.
+		// Sequential consistency is also required here, when racing with such a send.
+		if empty(c) {
+			// The channel is irreversibly closed and empty.
+			if raceenabled {
+				raceacquire(c.raceaddr())
+			}
+			if ep != nil {
+				typedmemclr(c.elemtype, ep)
+			}
+			return true, false
+		}
+	}
+
+	var t0 int64
+	if blockprofilerate > 0 {
+		t0 = cputicks()
+	}
+
+	lock(&c.lock)
+
+	if c.closed != 0 {
+		if c.qcount == 0 {
+			if raceenabled {
+				raceacquire(c.raceaddr())
+			}
+			unlock(&c.lock)
+			if ep != nil {
+				typedmemclr(c.elemtype, ep)
+			}
+			return true, false
+		}
+		// The channel has been closed, but the channel's buffer have data.
+	} else {
+		// Just found waiting sender with not closed.
+		if sg := c.sendq.dequeue(); sg != nil {
+			// Found a waiting sender. If buffer is size 0, receive value
+			// directly from sender. Otherwise, receive from head of queue
+			// and add sender's value to the tail of the queue (both map to
+			// the same buffer slot because the queue is full).
+			recv(c, sg, ep, func() { unlock(&c.lock) }, 3)
+			return true, true
+		}
+	}
+
+	if c.qcount > 0 {
+		// Receive directly from queue
+		qp := chanbuf(c, c.recvx)
+		if raceenabled {
+			racenotify(c, c.recvx, nil)
+		}
+		if ep != nil {
+			typedmemmove(c.elemtype, ep, qp)
+		}
+		typedmemclr(c.elemtype, qp)
+		c.recvx++
+		if c.recvx == c.dataqsiz {
+			c.recvx = 0
+		}
+		c.qcount--
+		unlock(&c.lock)
+		return true, true
+	}
+
+	if !block {
+		unlock(&c.lock)
+		return false, false
+	}
+
+	// no sender available: block on this channel.
+	gp := getg()
+	mysg := acquireSudog()
+	mysg.releasetime = 0
+	if t0 != 0 {
+		mysg.releasetime = -1
+	}
+	// No stack splits between assigning elem and enqueuing mysg
+	// on gp.waiting where copystack can find it.
+	mysg.elem = ep
+	mysg.waitlink = nil
+	gp.waiting = mysg
+	mysg.g = gp
+	mysg.isSelect = false
+	mysg.c = c
+	gp.param = nil
+	c.recvq.enqueue(mysg)
+	// Signal to anyone trying to shrink our stack that we're about
+	// to park on a channel. The window between when this G's status
+	// changes and when we set gp.activeStackChans is not safe for
+	// stack shrinking.
+	atomic.Store8(&gp.parkingOnChan, 1)
+	gopark(chanparkcommit, unsafe.Pointer(&c.lock), waitReasonChanReceive, traceEvGoBlockRecv, 2)
+
+	// someone woke us up
+	if mysg != gp.waiting {
+		throw("G waiting list is corrupted")
+	}
+	gp.waiting = nil
+	gp.activeStackChans = false
+	if mysg.releasetime > 0 {
+		blockevent(mysg.releasetime-t0, 2)
+	}
+	success := mysg.success
+	gp.param = nil
+	mysg.c = nil
+	releaseSudog(mysg)
+	return true, success
+}
+
+// recv processes a receive operation on a full channel c.
+// There are 2 parts:
+//  1. The value sent by the sender sg is put into the channel
+//     and the sender is woken up to go on its merry way.
+//  2. The value received by the receiver (the current G) is
+//     written to ep.
+//
+// For synchronous channels, both values are the same.
+// For asynchronous channels, the receiver gets its data from
+// the channel buffer and the sender's data is put in the
+// channel buffer.
+// Channel c must be full and locked. recv unlocks c with unlockf.
+// sg must already be dequeued from c.
+// A non-nil ep must point to the heap or the caller's stack.
+func recv(c *hchan, sg *sudog, ep unsafe.Pointer, unlockf func(), skip int) {
+	if c.dataqsiz == 0 {
+		if raceenabled {
+			racesync(c, sg)
+		}
+		if ep != nil {
+			// copy data from sender
+			recvDirect(c.elemtype, sg, ep)
+		}
+	} else {
+		// Queue is full. Take the item at the
+		// head of the queue. Make the sender enqueue
+		// its item at the tail of the queue. Since the
+		// queue is full, those are both the same slot.
+		qp := chanbuf(c, c.recvx)
+		if raceenabled {
+			racenotify(c, c.recvx, nil)
+			racenotify(c, c.recvx, sg)
+		}
+		// copy data from queue to receiver
+		if ep != nil {
+			typedmemmove(c.elemtype, ep, qp)
+		}
+		// copy data from sender to queue
+		typedmemmove(c.elemtype, qp, sg.elem)
+		c.recvx++
+		if c.recvx == c.dataqsiz {
+			c.recvx = 0
+		}
+		c.sendx = c.recvx // c.sendx = (c.sendx+1) % c.dataqsiz
+	}
+	sg.elem = nil
+	gp := sg.g
+	unlockf()
+	gp.param = unsafe.Pointer(sg)
+	sg.success = true
+	if sg.releasetime != 0 {
+		sg.releasetime = cputicks()
+	}
+	goready(gp, skip+1)
+}
+
+func chanparkcommit(gp *g, chanLock unsafe.Pointer) bool {
+	// There are unlocked sudogs that point into gp's stack. Stack
+	// copying must lock the channels of those sudogs.
+	// Set activeStackChans here instead of before we try parking
+	// because we could self-deadlock in stack growth on the
+	// channel lock.
+	gp.activeStackChans = true
+	// Mark that it's safe for stack shrinking to occur now,
+	// because any thread acquiring this G's stack for shrinking
+	// is guaranteed to observe activeStackChans after this store.
+	atomic.Store8(&gp.parkingOnChan, 0)
+	// Make sure we unlock after setting activeStackChans and
+	// unsetting parkingOnChan. The moment we unlock chanLock
+	// we risk gp getting readied by a channel operation and
+	// so gp could continue running before everything before
+	// the unlock is visible (even to gp itself).
+	unlock((*mutex)(chanLock))
+	return true
+}
+
+// compiler implements
+//
+//	select {
+//	case c <- v:
+//		... foo
+//	default:
+//		... bar
+//	}
+//
+// as
+//
+//	if selectnbsend(c, v) {
+//		... foo
+//	} else {
+//		... bar
+//	}
+func selectnbsend(c *hchan, elem unsafe.Pointer) (selected bool) {
+	return chansend(c, elem, false, getcallerpc())
+}
+
+// compiler implements
+//
+//	select {
+//	case v, ok = <-c:
+//		... foo
+//	default:
+//		... bar
+//	}
+//
+// as
+//
+//	if selected, ok = selectnbrecv(&v, c); selected {
+//		... foo
+//	} else {
+//		... bar
+//	}
+func selectnbrecv(elem unsafe.Pointer, c *hchan) (selected, received bool) {
+	return chanrecv(c, elem, false)
+}
+
+//go:linkname reflect_chansend reflect.chansend
+func reflect_chansend(c *hchan, elem unsafe.Pointer, nb bool) (selected bool) {
+	return chansend(c, elem, !nb, getcallerpc())
+}
+
+//go:linkname reflect_chanrecv reflect.chanrecv
+func reflect_chanrecv(c *hchan, nb bool, elem unsafe.Pointer) (selected bool, received bool) {
+	return chanrecv(c, elem, !nb)
+}
+
+//go:linkname reflect_chanlen reflect.chanlen
+func reflect_chanlen(c *hchan) int {
+	if c == nil {
+		return 0
+	}
+	return int(c.qcount)
+}
+
+//go:linkname reflectlite_chanlen internal/reflectlite.chanlen
+func reflectlite_chanlen(c *hchan) int {
+	if c == nil {
+		return 0
+	}
+	return int(c.qcount)
+}
+
+//go:linkname reflect_chancap reflect.chancap
+func reflect_chancap(c *hchan) int {
+	if c == nil {
+		return 0
+	}
+	return int(c.dataqsiz)
+}
+
+//go:linkname reflect_chanclose reflect.chanclose
+func reflect_chanclose(c *hchan) {
+	closechan(c)
+}
+
+func (q *waitq) enqueue(sgp *sudog) {
+	sgp.next = nil
+	x := q.last
+	if x == nil {
+		sgp.prev = nil
+		q.first = sgp
+		q.last = sgp
+		return
+	}
+	sgp.prev = x
+	x.next = sgp
+	q.last = sgp
+}
+
+func (q *waitq) dequeue() *sudog {
+	for {
+		sgp := q.first
+		if sgp == nil {
+			return nil
+		}
+		y := sgp.next
+		if y == nil {
+			q.first = nil
+			q.last = nil
+		} else {
+			y.prev = nil
+			q.first = y
+			sgp.next = nil // mark as removed (see dequeueSudoG)
+		}
+
+		// if a goroutine was put on this queue because of a
+		// select, there is a small window between the goroutine
+		// being woken up by a different case and it grabbing the
+		// channel locks. Once it has the lock
+		// it removes itself from the queue, so we won't see it after that.
+		// We use a flag in the G struct to tell us when someone
+		// else has won the race to signal this goroutine but the goroutine
+		// hasn't removed itself from the queue yet.
+		if sgp.isSelect && !atomic.Cas(&sgp.g.selectDone, 0, 1) {
+			continue
+		}
+
+		return sgp
+	}
+}
+
+func (c *hchan) raceaddr() unsafe.Pointer {
+	// Treat read-like and write-like operations on the channel to
+	// happen at this address. Avoid using the address of qcount
+	// or dataqsiz, because the len() and cap() builtins read
+	// those addresses, and we don't want them racing with
+	// operations like close().
+	return unsafe.Pointer(&c.buf)
+}
+
+func racesync(c *hchan, sg *sudog) {
+	racerelease(chanbuf(c, 0))
+	raceacquireg(sg.g, chanbuf(c, 0))
+	racereleaseg(sg.g, chanbuf(c, 0))
+	raceacquire(chanbuf(c, 0))
+}
+
+// Notify the race detector of a send or receive involving buffer entry idx
+// and a channel c or its communicating partner sg.
+// This function handles the special case of c.elemsize==0.
+func racenotify(c *hchan, idx uint, sg *sudog) {
+	// We could have passed the unsafe.Pointer corresponding to entry idx
+	// instead of idx itself.  However, in a future version of this function,
+	// we can use idx to better handle the case of elemsize==0.
+	// A future improvement to the detector is to call TSan with c and idx:
+	// this way, Go will continue to not allocating buffer entries for channels
+	// of elemsize==0, yet the race detector can be made to handle multiple
+	// sync objects underneath the hood (one sync object per idx)
+	qp := chanbuf(c, idx)
+	// When elemsize==0, we don't allocate a full buffer for the channel.
+	// Instead of individual buffer entries, the race detector uses the
+	// c.buf as the only buffer entry.  This simplification prevents us from
+	// following the memory model's happens-before rules (rules that are
+	// implemented in racereleaseacquire).  Instead, we accumulate happens-before
+	// information in the synchronization object associated with c.buf.
+	if c.elemsize == 0 {
+		if sg == nil {
+			raceacquire(qp)
+			racerelease(qp)
+		} else {
+			raceacquireg(sg.g, qp)
+			racereleaseg(sg.g, qp)
+		}
+	} else {
+		if sg == nil {
+			racereleaseacquire(qp)
+		} else {
+			racereleaseacquireg(sg.g, qp)
+		}
+	}
+}
diff --git a/contrib/go/_std_1.18/src/runtime/checkptr.go b/contrib/go/_std_1.19/src/runtime/checkptr.go
index 2d4afd5cf6..2d4afd5cf6 100644
--- a/contrib/go/_std_1.18/src/runtime/checkptr.go
+++ b/contrib/go/_std_1.19/src/runtime/checkptr.go
diff --git a/contrib/go/_std_1.19/src/runtime/compiler.go b/contrib/go/_std_1.19/src/runtime/compiler.go
new file mode 100644
index 0000000000..f430a27719
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/compiler.go
@@ -0,0 +1,12 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+// Compiler is the name of the compiler toolchain that built the
+// running binary. Known toolchains are:
+//
+//	gc      Also known as cmd/compile.
+//	gccgo   The gccgo front end, part of the GCC compiler suite.
+const Compiler = "gc"
diff --git a/contrib/go/_std_1.18/src/runtime/complex.go b/contrib/go/_std_1.19/src/runtime/complex.go
index 07c596fc0b..07c596fc0b 100644
--- a/contrib/go/_std_1.18/src/runtime/complex.go
+++ b/contrib/go/_std_1.19/src/runtime/complex.go
diff --git a/contrib/go/_std_1.18/src/runtime/cpuflags.go b/contrib/go/_std_1.19/src/runtime/cpuflags.go
index bbe93c5bea..bbe93c5bea 100644
--- a/contrib/go/_std_1.18/src/runtime/cpuflags.go
+++ b/contrib/go/_std_1.19/src/runtime/cpuflags.go
diff --git a/contrib/go/_std_1.18/src/runtime/cpuflags_amd64.go b/contrib/go/_std_1.19/src/runtime/cpuflags_amd64.go
index 8cca4bca8f..8cca4bca8f 100644
--- a/contrib/go/_std_1.18/src/runtime/cpuflags_amd64.go
+++ b/contrib/go/_std_1.19/src/runtime/cpuflags_amd64.go
diff --git a/contrib/go/_std_1.19/src/runtime/cpuprof.go b/contrib/go/_std_1.19/src/runtime/cpuprof.go
new file mode 100644
index 0000000000..2f7f6b4153
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/cpuprof.go
@@ -0,0 +1,238 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// CPU profiling.
+//
+// The signal handler for the profiling clock tick adds a new stack trace
+// to a log of recent traces. The log is read by a user goroutine that
+// turns it into formatted profile data. If the reader does not keep up
+// with the log, those writes will be recorded as a count of lost records.
+// The actual profile buffer is in profbuf.go.
+
+package runtime
+
+import (
+	"internal/abi"
+	"runtime/internal/atomic"
+	"runtime/internal/sys"
+	"unsafe"
+)
+
+const (
+	maxCPUProfStack = 64
+
+	// profBufWordCount is the size of the CPU profile buffer's storage for the
+	// header and stack of each sample, measured in 64-bit words. Every sample
+	// has a required header of two words. With a small additional header (a
+	// word or two) and stacks at the profiler's maximum length of 64 frames,
+	// that capacity can support 1900 samples or 19 thread-seconds at a 100 Hz
+	// sample rate, at a cost of 1 MiB.
+	profBufWordCount = 1 << 17
+	// profBufTagCount is the size of the CPU profile buffer's storage for the
+	// goroutine tags associated with each sample. A capacity of 1<<14 means
+	// room for 16k samples, or 160 thread-seconds at a 100 Hz sample rate.
+	profBufTagCount = 1 << 14
+)
+
+type cpuProfile struct {
+	lock mutex
+	on   bool     // profiling is on
+	log  *profBuf // profile events written here
+
+	// extra holds extra stacks accumulated in addNonGo
+	// corresponding to profiling signals arriving on
+	// non-Go-created threads. Those stacks are written
+	// to log the next time a normal Go thread gets the
+	// signal handler.
+	// Assuming the stacks are 2 words each (we don't get
+	// a full traceback from those threads), plus one word
+	// size for framing, 100 Hz profiling would generate
+	// 300 words per second.
+	// Hopefully a normal Go thread will get the profiling
+	// signal at least once every few seconds.
+	extra      [1000]uintptr
+	numExtra   int
+	lostExtra  uint64 // count of frames lost because extra is full
+	lostAtomic uint64 // count of frames lost because of being in atomic64 on mips/arm; updated racily
+}
+
+var cpuprof cpuProfile
+
+// SetCPUProfileRate sets the CPU profiling rate to hz samples per second.
+// If hz <= 0, SetCPUProfileRate turns off profiling.
+// If the profiler is on, the rate cannot be changed without first turning it off.
+//
+// Most clients should use the runtime/pprof package or
+// the testing package's -test.cpuprofile flag instead of calling
+// SetCPUProfileRate directly.
+func SetCPUProfileRate(hz int) {
+	// Clamp hz to something reasonable.
+	if hz < 0 {
+		hz = 0
+	}
+	if hz > 1000000 {
+		hz = 1000000
+	}
+
+	lock(&cpuprof.lock)
+	if hz > 0 {
+		if cpuprof.on || cpuprof.log != nil {
+			print("runtime: cannot set cpu profile rate until previous profile has finished.\n")
+			unlock(&cpuprof.lock)
+			return
+		}
+
+		cpuprof.on = true
+		cpuprof.log = newProfBuf(1, profBufWordCount, profBufTagCount)
+		hdr := [1]uint64{uint64(hz)}
+		cpuprof.log.write(nil, nanotime(), hdr[:], nil)
+		setcpuprofilerate(int32(hz))
+	} else if cpuprof.on {
+		setcpuprofilerate(0)
+		cpuprof.on = false
+		cpuprof.addExtra()
+		cpuprof.log.close()
+	}
+	unlock(&cpuprof.lock)
+}
+
+// add adds the stack trace to the profile.
+// It is called from signal handlers and other limited environments
+// and cannot allocate memory or acquire locks that might be
+// held at the time of the signal, nor can it use substantial amounts
+// of stack.
+//
+//go:nowritebarrierrec
+func (p *cpuProfile) add(tagPtr *unsafe.Pointer, stk []uintptr) {
+	// Simple cas-lock to coordinate with setcpuprofilerate.
+	for !atomic.Cas(&prof.signalLock, 0, 1) {
+		// TODO: Is it safe to osyield here? https://go.dev/issue/52672
+		osyield()
+	}
+
+	if prof.hz != 0 { // implies cpuprof.log != nil
+		if p.numExtra > 0 || p.lostExtra > 0 || p.lostAtomic > 0 {
+			p.addExtra()
+		}
+		hdr := [1]uint64{1}
+		// Note: write "knows" that the argument is &gp.labels,
+		// because otherwise its write barrier behavior may not
+		// be correct. See the long comment there before
+		// changing the argument here.
+		cpuprof.log.write(tagPtr, nanotime(), hdr[:], stk)
+	}
+
+	atomic.Store(&prof.signalLock, 0)
+}
+
+// addNonGo adds the non-Go stack trace to the profile.
+// It is called from a non-Go thread, so we cannot use much stack at all,
+// nor do anything that needs a g or an m.
+// In particular, we can't call cpuprof.log.write.
+// Instead, we copy the stack into cpuprof.extra,
+// which will be drained the next time a Go thread
+// gets the signal handling event.
+//
+//go:nosplit
+//go:nowritebarrierrec
+func (p *cpuProfile) addNonGo(stk []uintptr) {
+	// Simple cas-lock to coordinate with SetCPUProfileRate.
+	// (Other calls to add or addNonGo should be blocked out
+	// by the fact that only one SIGPROF can be handled by the
+	// process at a time. If not, this lock will serialize those too.
+	// The use of timer_create(2) on Linux to request process-targeted
+	// signals may have changed this.)
+	for !atomic.Cas(&prof.signalLock, 0, 1) {
+		// TODO: Is it safe to osyield here? https://go.dev/issue/52672
+		osyield()
+	}
+
+	if cpuprof.numExtra+1+len(stk) < len(cpuprof.extra) {
+		i := cpuprof.numExtra
+		cpuprof.extra[i] = uintptr(1 + len(stk))
+		copy(cpuprof.extra[i+1:], stk)
+		cpuprof.numExtra += 1 + len(stk)
+	} else {
+		cpuprof.lostExtra++
+	}
+
+	atomic.Store(&prof.signalLock, 0)
+}
+
+// addExtra adds the "extra" profiling events,
+// queued by addNonGo, to the profile log.
+// addExtra is called either from a signal handler on a Go thread
+// or from an ordinary goroutine; either way it can use stack
+// and has a g. The world may be stopped, though.
+func (p *cpuProfile) addExtra() {
+	// Copy accumulated non-Go profile events.
+	hdr := [1]uint64{1}
+	for i := 0; i < p.numExtra; {
+		p.log.write(nil, 0, hdr[:], p.extra[i+1:i+int(p.extra[i])])
+		i += int(p.extra[i])
+	}
+	p.numExtra = 0
+
+	// Report any lost events.
+	if p.lostExtra > 0 {
+		hdr := [1]uint64{p.lostExtra}
+		lostStk := [2]uintptr{
+			abi.FuncPCABIInternal(_LostExternalCode) + sys.PCQuantum,
+			abi.FuncPCABIInternal(_ExternalCode) + sys.PCQuantum,
+		}
+		p.log.write(nil, 0, hdr[:], lostStk[:])
+		p.lostExtra = 0
+	}
+
+	if p.lostAtomic > 0 {
+		hdr := [1]uint64{p.lostAtomic}
+		lostStk := [2]uintptr{
+			abi.FuncPCABIInternal(_LostSIGPROFDuringAtomic64) + sys.PCQuantum,
+			abi.FuncPCABIInternal(_System) + sys.PCQuantum,
+		}
+		p.log.write(nil, 0, hdr[:], lostStk[:])
+		p.lostAtomic = 0
+	}
+
+}
+
+// CPUProfile panics.
+// It formerly provided raw access to chunks of
+// a pprof-format profile generated by the runtime.
+// The details of generating that format have changed,
+// so this functionality has been removed.
+//
+// Deprecated: Use the runtime/pprof package,
+// or the handlers in the net/http/pprof package,
+// or the testing package's -test.cpuprofile flag instead.
+func CPUProfile() []byte {
+	panic("CPUProfile no longer available")
+}
+
+//go:linkname runtime_pprof_runtime_cyclesPerSecond runtime/pprof.runtime_cyclesPerSecond
+func runtime_pprof_runtime_cyclesPerSecond() int64 {
+	return tickspersecond()
+}
+
+// readProfile, provided to runtime/pprof, returns the next chunk of
+// binary CPU profiling stack trace data, blocking until data is available.
+// If profiling is turned off and all the profile data accumulated while it was
+// on has been returned, readProfile returns eof=true.
+// The caller must save the returned data and tags before calling readProfile again.
+// The returned data contains a whole number of records, and tags contains
+// exactly one entry per record.
+//
+//go:linkname runtime_pprof_readProfile runtime/pprof.readProfile
+func runtime_pprof_readProfile() ([]uint64, []unsafe.Pointer, bool) {
+	lock(&cpuprof.lock)
+	log := cpuprof.log
+	unlock(&cpuprof.lock)
+	data, tags, eof := log.read(profBufBlocking)
+	if len(data) == 0 && eof {
+		lock(&cpuprof.lock)
+		cpuprof.log = nil
+		unlock(&cpuprof.lock)
+	}
+	return data, tags, eof
+}
diff --git a/contrib/go/_std_1.19/src/runtime/cputicks.go b/contrib/go/_std_1.19/src/runtime/cputicks.go
new file mode 100644
index 0000000000..91270617fc
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/cputicks.go
@@ -0,0 +1,11 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !arm && !arm64 && !loong64 && !mips64 && !mips64le && !mips && !mipsle && !wasm
+
+package runtime
+
+// careful: cputicks is not guaranteed to be monotonic! In particular, we have
+// noticed drift between cpus on certain os/arch combinations. See issue 8976.
+func cputicks() int64
diff --git a/contrib/go/_std_1.19/src/runtime/debug.go b/contrib/go/_std_1.19/src/runtime/debug.go
new file mode 100644
index 0000000000..0ab23e0eb7
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/debug.go
@@ -0,0 +1,115 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+// GOMAXPROCS sets the maximum number of CPUs that can be executing
+// simultaneously and returns the previous setting. It defaults to
+// the value of runtime.NumCPU. If n < 1, it does not change the current setting.
+// This call will go away when the scheduler improves.
+func GOMAXPROCS(n int) int {
+	if GOARCH == "wasm" && n > 1 {
+		n = 1 // WebAssembly has no threads yet, so only one CPU is possible.
+	}
+
+	lock(&sched.lock)
+	ret := int(gomaxprocs)
+	unlock(&sched.lock)
+	if n <= 0 || n == ret {
+		return ret
+	}
+
+	stopTheWorldGC("GOMAXPROCS")
+
+	// newprocs will be processed by startTheWorld
+	newprocs = int32(n)
+
+	startTheWorldGC()
+	return ret
+}
+
+// NumCPU returns the number of logical CPUs usable by the current process.
+//
+// The set of available CPUs is checked by querying the operating system
+// at process startup. Changes to operating system CPU allocation after
+// process startup are not reflected.
+func NumCPU() int {
+	return int(ncpu)
+}
+
+// NumCgoCall returns the number of cgo calls made by the current process.
+func NumCgoCall() int64 {
+	var n = int64(atomic.Load64(&ncgocall))
+	for mp := (*m)(atomic.Loadp(unsafe.Pointer(&allm))); mp != nil; mp = mp.alllink {
+		n += int64(mp.ncgocall)
+	}
+	return n
+}
+
+// NumGoroutine returns the number of goroutines that currently exist.
+func NumGoroutine() int {
+	return int(gcount())
+}
+
+//go:linkname debug_modinfo runtime/debug.modinfo
+func debug_modinfo() string {
+	return modinfo
+}
+
+// mayMoreStackPreempt is a maymorestack hook that forces a preemption
+// at every possible cooperative preemption point.
+//
+// This is valuable to apply to the runtime, which can be sensitive to
+// preemption points. To apply this to all preemption points in the
+// runtime and runtime-like code, use the following in bash or zsh:
+//
+//	X=(-{gc,asm}flags={runtime/...,reflect,sync}=-d=maymorestack=runtime.mayMoreStackPreempt) GOFLAGS=${X[@]}
+//
+// This must be deeply nosplit because it is called from a function
+// prologue before the stack is set up and because the compiler will
+// call it from any splittable prologue (leading to infinite
+// recursion).
+//
+// Ideally it should also use very little stack because the linker
+// doesn't currently account for this in nosplit stack depth checking.
+//
+// Ensure mayMoreStackPreempt can be called for all ABIs.
+//
+//go:nosplit
+//go:linkname mayMoreStackPreempt
+func mayMoreStackPreempt() {
+	// Don't do anything on the g0 or gsignal stack.
+	g := getg()
+	if g == g.m.g0 || g == g.m.gsignal {
+		return
+	}
+	// Force a preemption, unless the stack is already poisoned.
+	if g.stackguard0 < stackPoisonMin {
+		g.stackguard0 = stackPreempt
+	}
+}
+
+// mayMoreStackMove is a maymorestack hook that forces stack movement
+// at every possible point.
+//
+// See mayMoreStackPreempt.
+//
+//go:nosplit
+//go:linkname mayMoreStackMove
+func mayMoreStackMove() {
+	// Don't do anything on the g0 or gsignal stack.
+	g := getg()
+	if g == g.m.g0 || g == g.m.gsignal {
+		return
+	}
+	// Force stack movement, unless the stack is already poisoned.
+	if g.stackguard0 < stackPoisonMin {
+		g.stackguard0 = stackForceMove
+	}
+}
diff --git a/contrib/go/_std_1.18/src/runtime/debugcall.go b/contrib/go/_std_1.19/src/runtime/debugcall.go
index 2f164e7fd7..2f164e7fd7 100644
--- a/contrib/go/_std_1.18/src/runtime/debugcall.go
+++ b/contrib/go/_std_1.19/src/runtime/debugcall.go
diff --git a/contrib/go/_std_1.19/src/runtime/debuglog.go b/contrib/go/_std_1.19/src/runtime/debuglog.go
new file mode 100644
index 0000000000..ca1a791c93
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/debuglog.go
@@ -0,0 +1,825 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file provides an internal debug logging facility. The debug
+// log is a lightweight, in-memory, per-M ring buffer. By default, the
+// runtime prints the debug log on panic.
+//
+// To print something to the debug log, call dlog to obtain a dlogger
+// and use the methods on that to add values. The values will be
+// space-separated in the output (much like println).
+//
+// This facility can be enabled by passing -tags debuglog when
+// building. Without this tag, dlog calls compile to nothing.
+
+package runtime
+
+import (
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+// debugLogBytes is the size of each per-M ring buffer. This is
+// allocated off-heap to avoid blowing up the M and hence the GC'd
+// heap size.
+const debugLogBytes = 16 << 10
+
+// debugLogStringLimit is the maximum number of bytes in a string.
+// Above this, the string will be truncated with "..(n more bytes).."
+const debugLogStringLimit = debugLogBytes / 8
+
+// dlog returns a debug logger. The caller can use methods on the
+// returned logger to add values, which will be space-separated in the
+// final output, much like println. The caller must call end() to
+// finish the message.
+//
+// dlog can be used from highly-constrained corners of the runtime: it
+// is safe to use in the signal handler, from within the write
+// barrier, from within the stack implementation, and in places that
+// must be recursively nosplit.
+//
+// This will be compiled away if built without the debuglog build tag.
+// However, argument construction may not be. If any of the arguments
+// are not literals or trivial expressions, consider protecting the
+// call with "if dlogEnabled".
+//
+//go:nosplit
+//go:nowritebarrierrec
+func dlog() *dlogger {
+	if !dlogEnabled {
+		return nil
+	}
+
+	// Get the time.
+	tick, nano := uint64(cputicks()), uint64(nanotime())
+
+	// Try to get a cached logger.
+	l := getCachedDlogger()
+
+	// If we couldn't get a cached logger, try to get one from the
+	// global pool.
+	if l == nil {
+		allp := (*uintptr)(unsafe.Pointer(&allDloggers))
+		all := (*dlogger)(unsafe.Pointer(atomic.Loaduintptr(allp)))
+		for l1 := all; l1 != nil; l1 = l1.allLink {
+			if atomic.Load(&l1.owned) == 0 && atomic.Cas(&l1.owned, 0, 1) {
+				l = l1
+				break
+			}
+		}
+	}
+
+	// If that failed, allocate a new logger.
+	if l == nil {
+		// Use sysAllocOS instead of sysAlloc because we want to interfere
+		// with the runtime as little as possible, and sysAlloc updates accounting.
+		l = (*dlogger)(sysAllocOS(unsafe.Sizeof(dlogger{})))
+		if l == nil {
+			throw("failed to allocate debug log")
+		}
+		l.w.r.data = &l.w.data
+		l.owned = 1
+
+		// Prepend to allDloggers list.
+		headp := (*uintptr)(unsafe.Pointer(&allDloggers))
+		for {
+			head := atomic.Loaduintptr(headp)
+			l.allLink = (*dlogger)(unsafe.Pointer(head))
+			if atomic.Casuintptr(headp, head, uintptr(unsafe.Pointer(l))) {
+				break
+			}
+		}
+	}
+
+	// If the time delta is getting too high, write a new sync
+	// packet. We set the limit so we don't write more than 6
+	// bytes of delta in the record header.
+	const deltaLimit = 1<<(3*7) - 1 // ~2ms between sync packets
+	if tick-l.w.tick > deltaLimit || nano-l.w.nano > deltaLimit {
+		l.w.writeSync(tick, nano)
+	}
+
+	// Reserve space for framing header.
+	l.w.ensure(debugLogHeaderSize)
+	l.w.write += debugLogHeaderSize
+
+	// Write record header.
+	l.w.uvarint(tick - l.w.tick)
+	l.w.uvarint(nano - l.w.nano)
+	gp := getg()
+	if gp != nil && gp.m != nil && gp.m.p != 0 {
+		l.w.varint(int64(gp.m.p.ptr().id))
+	} else {
+		l.w.varint(-1)
+	}
+
+	return l
+}
+
+// A dlogger writes to the debug log.
+//
+// To obtain a dlogger, call dlog(). When done with the dlogger, call
+// end().
+//
+//go:notinheap
+type dlogger struct {
+	w debugLogWriter
+
+	// allLink is the next dlogger in the allDloggers list.
+	allLink *dlogger
+
+	// owned indicates that this dlogger is owned by an M. This is
+	// accessed atomically.
+	owned uint32
+}
+
+// allDloggers is a list of all dloggers, linked through
+// dlogger.allLink. This is accessed atomically. This is prepend only,
+// so it doesn't need to protect against ABA races.
+var allDloggers *dlogger
+
+//go:nosplit
+func (l *dlogger) end() {
+	if !dlogEnabled {
+		return
+	}
+
+	// Fill in framing header.
+	size := l.w.write - l.w.r.end
+	if !l.w.writeFrameAt(l.w.r.end, size) {
+		throw("record too large")
+	}
+
+	// Commit the record.
+	l.w.r.end = l.w.write
+
+	// Attempt to return this logger to the cache.
+	if putCachedDlogger(l) {
+		return
+	}
+
+	// Return the logger to the global pool.
+	atomic.Store(&l.owned, 0)
+}
+
+const (
+	debugLogUnknown = 1 + iota
+	debugLogBoolTrue
+	debugLogBoolFalse
+	debugLogInt
+	debugLogUint
+	debugLogHex
+	debugLogPtr
+	debugLogString
+	debugLogConstString
+	debugLogStringOverflow
+
+	debugLogPC
+	debugLogTraceback
+)
+
+//go:nosplit
+func (l *dlogger) b(x bool) *dlogger {
+	if !dlogEnabled {
+		return l
+	}
+	if x {
+		l.w.byte(debugLogBoolTrue)
+	} else {
+		l.w.byte(debugLogBoolFalse)
+	}
+	return l
+}
+
+//go:nosplit
+func (l *dlogger) i(x int) *dlogger {
+	return l.i64(int64(x))
+}
+
+//go:nosplit
+func (l *dlogger) i8(x int8) *dlogger {
+	return l.i64(int64(x))
+}
+
+//go:nosplit
+func (l *dlogger) i16(x int16) *dlogger {
+	return l.i64(int64(x))
+}
+
+//go:nosplit
+func (l *dlogger) i32(x int32) *dlogger {
+	return l.i64(int64(x))
+}
+
+//go:nosplit
+func (l *dlogger) i64(x int64) *dlogger {
+	if !dlogEnabled {
+		return l
+	}
+	l.w.byte(debugLogInt)
+	l.w.varint(x)
+	return l
+}
+
+//go:nosplit
+func (l *dlogger) u(x uint) *dlogger {
+	return l.u64(uint64(x))
+}
+
+//go:nosplit
+func (l *dlogger) uptr(x uintptr) *dlogger {
+	return l.u64(uint64(x))
+}
+
+//go:nosplit
+func (l *dlogger) u8(x uint8) *dlogger {
+	return l.u64(uint64(x))
+}
+
+//go:nosplit
+func (l *dlogger) u16(x uint16) *dlogger {
+	return l.u64(uint64(x))
+}
+
+//go:nosplit
+func (l *dlogger) u32(x uint32) *dlogger {
+	return l.u64(uint64(x))
+}
+
+//go:nosplit
+func (l *dlogger) u64(x uint64) *dlogger {
+	if !dlogEnabled {
+		return l
+	}
+	l.w.byte(debugLogUint)
+	l.w.uvarint(x)
+	return l
+}
+
+//go:nosplit
+func (l *dlogger) hex(x uint64) *dlogger {
+	if !dlogEnabled {
+		return l
+	}
+	l.w.byte(debugLogHex)
+	l.w.uvarint(x)
+	return l
+}
+
+//go:nosplit
+func (l *dlogger) p(x any) *dlogger {
+	if !dlogEnabled {
+		return l
+	}
+	l.w.byte(debugLogPtr)
+	if x == nil {
+		l.w.uvarint(0)
+	} else {
+		v := efaceOf(&x)
+		switch v._type.kind & kindMask {
+		case kindChan, kindFunc, kindMap, kindPtr, kindUnsafePointer:
+			l.w.uvarint(uint64(uintptr(v.data)))
+		default:
+			throw("not a pointer type")
+		}
+	}
+	return l
+}
+
+//go:nosplit
+func (l *dlogger) s(x string) *dlogger {
+	if !dlogEnabled {
+		return l
+	}
+	str := stringStructOf(&x)
+	datap := &firstmoduledata
+	if len(x) > 4 && datap.etext <= uintptr(str.str) && uintptr(str.str) < datap.end {
+		// String constants are in the rodata section, which
+		// isn't recorded in moduledata. But it has to be
+		// somewhere between etext and end.
+		l.w.byte(debugLogConstString)
+		l.w.uvarint(uint64(str.len))
+		l.w.uvarint(uint64(uintptr(str.str) - datap.etext))
+	} else {
+		l.w.byte(debugLogString)
+		var b []byte
+		bb := (*slice)(unsafe.Pointer(&b))
+		bb.array = str.str
+		bb.len, bb.cap = str.len, str.len
+		if len(b) > debugLogStringLimit {
+			b = b[:debugLogStringLimit]
+		}
+		l.w.uvarint(uint64(len(b)))
+		l.w.bytes(b)
+		if len(b) != len(x) {
+			l.w.byte(debugLogStringOverflow)
+			l.w.uvarint(uint64(len(x) - len(b)))
+		}
+	}
+	return l
+}
+
+//go:nosplit
+func (l *dlogger) pc(x uintptr) *dlogger {
+	if !dlogEnabled {
+		return l
+	}
+	l.w.byte(debugLogPC)
+	l.w.uvarint(uint64(x))
+	return l
+}
+
+//go:nosplit
+func (l *dlogger) traceback(x []uintptr) *dlogger {
+	if !dlogEnabled {
+		return l
+	}
+	l.w.byte(debugLogTraceback)
+	l.w.uvarint(uint64(len(x)))
+	for _, pc := range x {
+		l.w.uvarint(uint64(pc))
+	}
+	return l
+}
+
+// A debugLogWriter is a ring buffer of binary debug log records.
+//
+// A log record consists of a 2-byte framing header and a sequence of
+// fields. The framing header gives the size of the record as a little
+// endian 16-bit value. Each field starts with a byte indicating its
+// type, followed by type-specific data. If the size in the framing
+// header is 0, it's a sync record consisting of two little endian
+// 64-bit values giving a new time base.
+//
+// Because this is a ring buffer, new records will eventually
+// overwrite old records. Hence, it maintains a reader that consumes
+// the log as it gets overwritten. That reader state is where an
+// actual log reader would start.
+//
+//go:notinheap
+type debugLogWriter struct {
+	write uint64
+	data  debugLogBuf
+
+	// tick and nano are the time bases from the most recently
+	// written sync record.
+	tick, nano uint64
+
+	// r is a reader that consumes records as they get overwritten
+	// by the writer. It also acts as the initial reader state
+	// when printing the log.
+	r debugLogReader
+
+	// buf is a scratch buffer for encoding. This is here to
+	// reduce stack usage.
+	buf [10]byte
+}
+
+//go:notinheap
+type debugLogBuf [debugLogBytes]byte
+
+const (
+	// debugLogHeaderSize is the number of bytes in the framing
+	// header of every dlog record.
+	debugLogHeaderSize = 2
+
+	// debugLogSyncSize is the number of bytes in a sync record.
+	debugLogSyncSize = debugLogHeaderSize + 2*8
+)
+
+//go:nosplit
+func (l *debugLogWriter) ensure(n uint64) {
+	for l.write+n >= l.r.begin+uint64(len(l.data)) {
+		// Consume record at begin.
+		if l.r.skip() == ^uint64(0) {
+			// Wrapped around within a record.
+			//
+			// TODO(austin): It would be better to just
+			// eat the whole buffer at this point, but we
+			// have to communicate that to the reader
+			// somehow.
+			throw("record wrapped around")
+		}
+	}
+}
+
+//go:nosplit
+func (l *debugLogWriter) writeFrameAt(pos, size uint64) bool {
+	l.data[pos%uint64(len(l.data))] = uint8(size)
+	l.data[(pos+1)%uint64(len(l.data))] = uint8(size >> 8)
+	return size <= 0xFFFF
+}
+
+//go:nosplit
+func (l *debugLogWriter) writeSync(tick, nano uint64) {
+	l.tick, l.nano = tick, nano
+	l.ensure(debugLogHeaderSize)
+	l.writeFrameAt(l.write, 0)
+	l.write += debugLogHeaderSize
+	l.writeUint64LE(tick)
+	l.writeUint64LE(nano)
+	l.r.end = l.write
+}
+
+//go:nosplit
+func (l *debugLogWriter) writeUint64LE(x uint64) {
+	var b [8]byte
+	b[0] = byte(x)
+	b[1] = byte(x >> 8)
+	b[2] = byte(x >> 16)
+	b[3] = byte(x >> 24)
+	b[4] = byte(x >> 32)
+	b[5] = byte(x >> 40)
+	b[6] = byte(x >> 48)
+	b[7] = byte(x >> 56)
+	l.bytes(b[:])
+}
+
+//go:nosplit
+func (l *debugLogWriter) byte(x byte) {
+	l.ensure(1)
+	pos := l.write
+	l.write++
+	l.data[pos%uint64(len(l.data))] = x
+}
+
+//go:nosplit
+func (l *debugLogWriter) bytes(x []byte) {
+	l.ensure(uint64(len(x)))
+	pos := l.write
+	l.write += uint64(len(x))
+	for len(x) > 0 {
+		n := copy(l.data[pos%uint64(len(l.data)):], x)
+		pos += uint64(n)
+		x = x[n:]
+	}
+}
+
+//go:nosplit
+func (l *debugLogWriter) varint(x int64) {
+	var u uint64
+	if x < 0 {
+		u = (^uint64(x) << 1) | 1 // complement i, bit 0 is 1
+	} else {
+		u = (uint64(x) << 1) // do not complement i, bit 0 is 0
+	}
+	l.uvarint(u)
+}
+
+//go:nosplit
+func (l *debugLogWriter) uvarint(u uint64) {
+	i := 0
+	for u >= 0x80 {
+		l.buf[i] = byte(u) | 0x80
+		u >>= 7
+		i++
+	}
+	l.buf[i] = byte(u)
+	i++
+	l.bytes(l.buf[:i])
+}
+
+type debugLogReader struct {
+	data *debugLogBuf
+
+	// begin and end are the positions in the log of the beginning
+	// and end of the log data, modulo len(data).
+	begin, end uint64
+
+	// tick and nano are the current time base at begin.
+	tick, nano uint64
+}
+
+//go:nosplit
+func (r *debugLogReader) skip() uint64 {
+	// Read size at pos.
+	if r.begin+debugLogHeaderSize > r.end {
+		return ^uint64(0)
+	}
+	size := uint64(r.readUint16LEAt(r.begin))
+	if size == 0 {
+		// Sync packet.
+		r.tick = r.readUint64LEAt(r.begin + debugLogHeaderSize)
+		r.nano = r.readUint64LEAt(r.begin + debugLogHeaderSize + 8)
+		size = debugLogSyncSize
+	}
+	if r.begin+size > r.end {
+		return ^uint64(0)
+	}
+	r.begin += size
+	return size
+}
+
+//go:nosplit
+func (r *debugLogReader) readUint16LEAt(pos uint64) uint16 {
+	return uint16(r.data[pos%uint64(len(r.data))]) |
+		uint16(r.data[(pos+1)%uint64(len(r.data))])<<8
+}
+
+//go:nosplit
+func (r *debugLogReader) readUint64LEAt(pos uint64) uint64 {
+	var b [8]byte
+	for i := range b {
+		b[i] = r.data[pos%uint64(len(r.data))]
+		pos++
+	}
+	return uint64(b[0]) | uint64(b[1])<<8 |
+		uint64(b[2])<<16 | uint64(b[3])<<24 |
+		uint64(b[4])<<32 | uint64(b[5])<<40 |
+		uint64(b[6])<<48 | uint64(b[7])<<56
+}
+
+func (r *debugLogReader) peek() (tick uint64) {
+	// Consume any sync records.
+	size := uint64(0)
+	for size == 0 {
+		if r.begin+debugLogHeaderSize > r.end {
+			return ^uint64(0)
+		}
+		size = uint64(r.readUint16LEAt(r.begin))
+		if size != 0 {
+			break
+		}
+		if r.begin+debugLogSyncSize > r.end {
+			return ^uint64(0)
+		}
+		// Sync packet.
+		r.tick = r.readUint64LEAt(r.begin + debugLogHeaderSize)
+		r.nano = r.readUint64LEAt(r.begin + debugLogHeaderSize + 8)
+		r.begin += debugLogSyncSize
+	}
+
+	// Peek tick delta.
+	if r.begin+size > r.end {
+		return ^uint64(0)
+	}
+	pos := r.begin + debugLogHeaderSize
+	var u uint64
+	for i := uint(0); ; i += 7 {
+		b := r.data[pos%uint64(len(r.data))]
+		pos++
+		u |= uint64(b&^0x80) << i
+		if b&0x80 == 0 {
+			break
+		}
+	}
+	if pos > r.begin+size {
+		return ^uint64(0)
+	}
+	return r.tick + u
+}
+
+func (r *debugLogReader) header() (end, tick, nano uint64, p int) {
+	// Read size. We've already skipped sync packets and checked
+	// bounds in peek.
+	size := uint64(r.readUint16LEAt(r.begin))
+	end = r.begin + size
+	r.begin += debugLogHeaderSize
+
+	// Read tick, nano, and p.
+	tick = r.uvarint() + r.tick
+	nano = r.uvarint() + r.nano
+	p = int(r.varint())
+
+	return
+}
+
+func (r *debugLogReader) uvarint() uint64 {
+	var u uint64
+	for i := uint(0); ; i += 7 {
+		b := r.data[r.begin%uint64(len(r.data))]
+		r.begin++
+		u |= uint64(b&^0x80) << i
+		if b&0x80 == 0 {
+			break
+		}
+	}
+	return u
+}
+
+func (r *debugLogReader) varint() int64 {
+	u := r.uvarint()
+	var v int64
+	if u&1 == 0 {
+		v = int64(u >> 1)
+	} else {
+		v = ^int64(u >> 1)
+	}
+	return v
+}
+
+func (r *debugLogReader) printVal() bool {
+	typ := r.data[r.begin%uint64(len(r.data))]
+	r.begin++
+
+	switch typ {
+	default:
+		print("<unknown field type ", hex(typ), " pos ", r.begin-1, " end ", r.end, ">\n")
+		return false
+
+	case debugLogUnknown:
+		print("<unknown kind>")
+
+	case debugLogBoolTrue:
+		print(true)
+
+	case debugLogBoolFalse:
+		print(false)
+
+	case debugLogInt:
+		print(r.varint())
+
+	case debugLogUint:
+		print(r.uvarint())
+
+	case debugLogHex, debugLogPtr:
+		print(hex(r.uvarint()))
+
+	case debugLogString:
+		sl := r.uvarint()
+		if r.begin+sl > r.end {
+			r.begin = r.end
+			print("<string length corrupted>")
+			break
+		}
+		for sl > 0 {
+			b := r.data[r.begin%uint64(len(r.data)):]
+			if uint64(len(b)) > sl {
+				b = b[:sl]
+			}
+			r.begin += uint64(len(b))
+			sl -= uint64(len(b))
+			gwrite(b)
+		}
+
+	case debugLogConstString:
+		len, ptr := int(r.uvarint()), uintptr(r.uvarint())
+		ptr += firstmoduledata.etext
+		str := stringStruct{
+			str: unsafe.Pointer(ptr),
+			len: len,
+		}
+		s := *(*string)(unsafe.Pointer(&str))
+		print(s)
+
+	case debugLogStringOverflow:
+		print("..(", r.uvarint(), " more bytes)..")
+
+	case debugLogPC:
+		printDebugLogPC(uintptr(r.uvarint()), false)
+
+	case debugLogTraceback:
+		n := int(r.uvarint())
+		for i := 0; i < n; i++ {
+			print("\n\t")
+			// gentraceback PCs are always return PCs.
+			// Convert them to call PCs.
+			//
+			// TODO(austin): Expand inlined frames.
+			printDebugLogPC(uintptr(r.uvarint()), true)
+		}
+	}
+
+	return true
+}
+
+// printDebugLog prints the debug log.
+func printDebugLog() {
+	if !dlogEnabled {
+		return
+	}
+
+	// This function should not panic or throw since it is used in
+	// the fatal panic path and this may deadlock.
+
+	printlock()
+
+	// Get the list of all debug logs.
+	allp := (*uintptr)(unsafe.Pointer(&allDloggers))
+	all := (*dlogger)(unsafe.Pointer(atomic.Loaduintptr(allp)))
+
+	// Count the logs.
+	n := 0
+	for l := all; l != nil; l = l.allLink {
+		n++
+	}
+	if n == 0 {
+		printunlock()
+		return
+	}
+
+	// Prepare read state for all logs.
+	type readState struct {
+		debugLogReader
+		first    bool
+		lost     uint64
+		nextTick uint64
+	}
+	// Use sysAllocOS instead of sysAlloc because we want to interfere
+	// with the runtime as little as possible, and sysAlloc updates accounting.
+	state1 := sysAllocOS(unsafe.Sizeof(readState{}) * uintptr(n))
+	if state1 == nil {
+		println("failed to allocate read state for", n, "logs")
+		printunlock()
+		return
+	}
+	state := (*[1 << 20]readState)(state1)[:n]
+	{
+		l := all
+		for i := range state {
+			s := &state[i]
+			s.debugLogReader = l.w.r
+			s.first = true
+			s.lost = l.w.r.begin
+			s.nextTick = s.peek()
+			l = l.allLink
+		}
+	}
+
+	// Print records.
+	for {
+		// Find the next record.
+		var best struct {
+			tick uint64
+			i    int
+		}
+		best.tick = ^uint64(0)
+		for i := range state {
+			if state[i].nextTick < best.tick {
+				best.tick = state[i].nextTick
+				best.i = i
+			}
+		}
+		if best.tick == ^uint64(0) {
+			break
+		}
+
+		// Print record.
+		s := &state[best.i]
+		if s.first {
+			print(">> begin log ", best.i)
+			if s.lost != 0 {
+				print("; lost first ", s.lost>>10, "KB")
+			}
+			print(" <<\n")
+			s.first = false
+		}
+
+		end, _, nano, p := s.header()
+		oldEnd := s.end
+		s.end = end
+
+		print("[")
+		var tmpbuf [21]byte
+		pnano := int64(nano) - runtimeInitTime
+		if pnano < 0 {
+			// Logged before runtimeInitTime was set.
+			pnano = 0
+		}
+		pnanoBytes := itoaDiv(tmpbuf[:], uint64(pnano), 9)
+		print(slicebytetostringtmp((*byte)(noescape(unsafe.Pointer(&pnanoBytes[0]))), len(pnanoBytes)))
+		print(" P ", p, "] ")
+
+		for i := 0; s.begin < s.end; i++ {
+			if i > 0 {
+				print(" ")
+			}
+			if !s.printVal() {
+				// Abort this P log.
+				print("<aborting P log>")
+				end = oldEnd
+				break
+			}
+		}
+		println()
+
+		// Move on to the next record.
+		s.begin = end
+		s.end = oldEnd
+		s.nextTick = s.peek()
+	}
+
+	printunlock()
+}
+
+// printDebugLogPC prints a single symbolized PC. If returnPC is true,
+// pc is a return PC that must first be converted to a call PC.
+func printDebugLogPC(pc uintptr, returnPC bool) {
+	fn := findfunc(pc)
+	if returnPC && (!fn.valid() || pc > fn.entry()) {
+		// TODO(austin): Don't back up if the previous frame
+		// was a sigpanic.
+		pc--
+	}
+
+	print(hex(pc))
+	if !fn.valid() {
+		print(" [unknown PC]")
+	} else {
+		name := funcname(fn)
+		file, line := funcline(fn, pc)
+		print(" [", name, "+", hex(pc-fn.entry()),
+			" ", file, ":", line, "]")
+	}
+}
diff --git a/contrib/go/_std_1.18/src/runtime/debuglog_off.go b/contrib/go/_std_1.19/src/runtime/debuglog_off.go
index fa3be39c70..fa3be39c70 100644
--- a/contrib/go/_std_1.18/src/runtime/debuglog_off.go
+++ b/contrib/go/_std_1.19/src/runtime/debuglog_off.go
diff --git a/contrib/go/_std_1.18/src/runtime/defs_darwin_amd64.go b/contrib/go/_std_1.19/src/runtime/defs_darwin_amd64.go
index cbc26bfcff..cbc26bfcff 100644
--- a/contrib/go/_std_1.18/src/runtime/defs_darwin_amd64.go
+++ b/contrib/go/_std_1.19/src/runtime/defs_darwin_amd64.go
diff --git a/contrib/go/_std_1.19/src/runtime/defs_linux_amd64.go b/contrib/go/_std_1.19/src/runtime/defs_linux_amd64.go
new file mode 100644
index 0000000000..da4d357532
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/defs_linux_amd64.go
@@ -0,0 +1,301 @@
+// created by cgo -cdefs and then converted to Go
+// cgo -cdefs defs_linux.go defs1_linux.go
+
+package runtime
+
+import "unsafe"
+
+const (
+	_EINTR  = 0x4
+	_EAGAIN = 0xb
+	_ENOMEM = 0xc
+
+	_PROT_NONE  = 0x0
+	_PROT_READ  = 0x1
+	_PROT_WRITE = 0x2
+	_PROT_EXEC  = 0x4
+
+	_MAP_ANON    = 0x20
+	_MAP_PRIVATE = 0x2
+	_MAP_FIXED   = 0x10
+
+	_MADV_DONTNEED   = 0x4
+	_MADV_FREE       = 0x8
+	_MADV_HUGEPAGE   = 0xe
+	_MADV_NOHUGEPAGE = 0xf
+
+	_SA_RESTART  = 0x10000000
+	_SA_ONSTACK  = 0x8000000
+	_SA_RESTORER = 0x4000000
+	_SA_SIGINFO  = 0x4
+
+	_SI_KERNEL = 0x80
+	_SI_TIMER  = -0x2
+
+	_SIGHUP    = 0x1
+	_SIGINT    = 0x2
+	_SIGQUIT   = 0x3
+	_SIGILL    = 0x4
+	_SIGTRAP   = 0x5
+	_SIGABRT   = 0x6
+	_SIGBUS    = 0x7
+	_SIGFPE    = 0x8
+	_SIGKILL   = 0x9
+	_SIGUSR1   = 0xa
+	_SIGSEGV   = 0xb
+	_SIGUSR2   = 0xc
+	_SIGPIPE   = 0xd
+	_SIGALRM   = 0xe
+	_SIGSTKFLT = 0x10
+	_SIGCHLD   = 0x11
+	_SIGCONT   = 0x12
+	_SIGSTOP   = 0x13
+	_SIGTSTP   = 0x14
+	_SIGTTIN   = 0x15
+	_SIGTTOU   = 0x16
+	_SIGURG    = 0x17
+	_SIGXCPU   = 0x18
+	_SIGXFSZ   = 0x19
+	_SIGVTALRM = 0x1a
+	_SIGPROF   = 0x1b
+	_SIGWINCH  = 0x1c
+	_SIGIO     = 0x1d
+	_SIGPWR    = 0x1e
+	_SIGSYS    = 0x1f
+
+	_SIGRTMIN = 0x20
+
+	_FPE_INTDIV = 0x1
+	_FPE_INTOVF = 0x2
+	_FPE_FLTDIV = 0x3
+	_FPE_FLTOVF = 0x4
+	_FPE_FLTUND = 0x5
+	_FPE_FLTRES = 0x6
+	_FPE_FLTINV = 0x7
+	_FPE_FLTSUB = 0x8
+
+	_BUS_ADRALN = 0x1
+	_BUS_ADRERR = 0x2
+	_BUS_OBJERR = 0x3
+
+	_SEGV_MAPERR = 0x1
+	_SEGV_ACCERR = 0x2
+
+	_ITIMER_REAL    = 0x0
+	_ITIMER_VIRTUAL = 0x1
+	_ITIMER_PROF    = 0x2
+
+	_CLOCK_THREAD_CPUTIME_ID = 0x3
+
+	_SIGEV_THREAD_ID = 0x4
+
+	_EPOLLIN       = 0x1
+	_EPOLLOUT      = 0x4
+	_EPOLLERR      = 0x8
+	_EPOLLHUP      = 0x10
+	_EPOLLRDHUP    = 0x2000
+	_EPOLLET       = 0x80000000
+	_EPOLL_CLOEXEC = 0x80000
+	_EPOLL_CTL_ADD = 0x1
+	_EPOLL_CTL_DEL = 0x2
+	_EPOLL_CTL_MOD = 0x3
+
+	_AF_UNIX    = 0x1
+	_SOCK_DGRAM = 0x2
+)
+
+type timespec struct {
+	tv_sec  int64
+	tv_nsec int64
+}
+
+//go:nosplit
+func (ts *timespec) setNsec(ns int64) {
+	ts.tv_sec = ns / 1e9
+	ts.tv_nsec = ns % 1e9
+}
+
+type timeval struct {
+	tv_sec  int64
+	tv_usec int64
+}
+
+func (tv *timeval) set_usec(x int32) {
+	tv.tv_usec = int64(x)
+}
+
+type sigactiont struct {
+	sa_handler  uintptr
+	sa_flags    uint64
+	sa_restorer uintptr
+	sa_mask     uint64
+}
+
+type siginfoFields struct {
+	si_signo int32
+	si_errno int32
+	si_code  int32
+	// below here is a union; si_addr is the only field we use
+	si_addr uint64
+}
+
+type siginfo struct {
+	siginfoFields
+
+	// Pad struct to the max size in the kernel.
+	_ [_si_max_size - unsafe.Sizeof(siginfoFields{})]byte
+}
+
+type itimerspec struct {
+	it_interval timespec
+	it_value    timespec
+}
+
+type itimerval struct {
+	it_interval timeval
+	it_value    timeval
+}
+
+type sigeventFields struct {
+	value  uintptr
+	signo  int32
+	notify int32
+	// below here is a union; sigev_notify_thread_id is the only field we use
+	sigev_notify_thread_id int32
+}
+
+type sigevent struct {
+	sigeventFields
+
+	// Pad struct to the max size in the kernel.
+	_ [_sigev_max_size - unsafe.Sizeof(sigeventFields{})]byte
+}
+
+type epollevent struct {
+	events uint32
+	data   [8]byte // unaligned uintptr
+}
+
+// created by cgo -cdefs and then converted to Go
+// cgo -cdefs defs_linux.go defs1_linux.go
+
+const (
+	_O_RDONLY   = 0x0
+	_O_NONBLOCK = 0x800
+	_O_CLOEXEC  = 0x80000
+)
+
+type usigset struct {
+	__val [16]uint64
+}
+
+type fpxreg struct {
+	significand [4]uint16
+	exponent    uint16
+	padding     [3]uint16
+}
+
+type xmmreg struct {
+	element [4]uint32
+}
+
+type fpstate struct {
+	cwd       uint16
+	swd       uint16
+	ftw       uint16
+	fop       uint16
+	rip       uint64
+	rdp       uint64
+	mxcsr     uint32
+	mxcr_mask uint32
+	_st       [8]fpxreg
+	_xmm      [16]xmmreg
+	padding   [24]uint32
+}
+
+type fpxreg1 struct {
+	significand [4]uint16
+	exponent    uint16
+	padding     [3]uint16
+}
+
+type xmmreg1 struct {
+	element [4]uint32
+}
+
+type fpstate1 struct {
+	cwd       uint16
+	swd       uint16
+	ftw       uint16
+	fop       uint16
+	rip       uint64
+	rdp       uint64
+	mxcsr     uint32
+	mxcr_mask uint32
+	_st       [8]fpxreg1
+	_xmm      [16]xmmreg1
+	padding   [24]uint32
+}
+
+type fpreg1 struct {
+	significand [4]uint16
+	exponent    uint16
+}
+
+type stackt struct {
+	ss_sp     *byte
+	ss_flags  int32
+	pad_cgo_0 [4]byte
+	ss_size   uintptr
+}
+
+type mcontext struct {
+	gregs       [23]uint64
+	fpregs      *fpstate
+	__reserved1 [8]uint64
+}
+
+type ucontext struct {
+	uc_flags     uint64
+	uc_link      *ucontext
+	uc_stack     stackt
+	uc_mcontext  mcontext
+	uc_sigmask   usigset
+	__fpregs_mem fpstate
+}
+
+type sigcontext struct {
+	r8          uint64
+	r9          uint64
+	r10         uint64
+	r11         uint64
+	r12         uint64
+	r13         uint64
+	r14         uint64
+	r15         uint64
+	rdi         uint64
+	rsi         uint64
+	rbp         uint64
+	rbx         uint64
+	rdx         uint64
+	rax         uint64
+	rcx         uint64
+	rsp         uint64
+	rip         uint64
+	eflags      uint64
+	cs          uint16
+	gs          uint16
+	fs          uint16
+	__pad0      uint16
+	err         uint64
+	trapno      uint64
+	oldmask     uint64
+	cr2         uint64
+	fpstate     *fpstate1
+	__reserved1 [8]uint64
+}
+
+type sockaddr_un struct {
+	family uint16
+	path   [108]byte
+}
diff --git a/contrib/go/_std_1.18/src/runtime/duff_amd64.s b/contrib/go/_std_1.19/src/runtime/duff_amd64.s
index df010f5853..df010f5853 100644
--- a/contrib/go/_std_1.18/src/runtime/duff_amd64.s
+++ b/contrib/go/_std_1.19/src/runtime/duff_amd64.s
diff --git a/contrib/go/_std_1.19/src/runtime/env_posix.go b/contrib/go/_std_1.19/src/runtime/env_posix.go
new file mode 100644
index 0000000000..94a19d80d8
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/env_posix.go
@@ -0,0 +1,78 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm) || windows || plan9
+
+package runtime
+
+import "unsafe"
+
+func gogetenv(key string) string {
+	env := environ()
+	if env == nil {
+		throw("getenv before env init")
+	}
+	for _, s := range env {
+		if len(s) > len(key) && s[len(key)] == '=' && envKeyEqual(s[:len(key)], key) {
+			return s[len(key)+1:]
+		}
+	}
+	return ""
+}
+
+// envKeyEqual reports whether a == b, with ASCII-only case insensitivity
+// on Windows. The two strings must have the same length.
+func envKeyEqual(a, b string) bool {
+	if GOOS == "windows" { // case insensitive
+		for i := 0; i < len(a); i++ {
+			ca, cb := a[i], b[i]
+			if ca == cb || lowerASCII(ca) == lowerASCII(cb) {
+				continue
+			}
+			return false
+		}
+		return true
+	}
+	return a == b
+}
+
+func lowerASCII(c byte) byte {
+	if 'A' <= c && c <= 'Z' {
+		return c + ('a' - 'A')
+	}
+	return c
+}
+
+var _cgo_setenv unsafe.Pointer   // pointer to C function
+var _cgo_unsetenv unsafe.Pointer // pointer to C function
+
+// Update the C environment if cgo is loaded.
+// Called from syscall.Setenv.
+//
+//go:linkname syscall_setenv_c syscall.setenv_c
+func syscall_setenv_c(k string, v string) {
+	if _cgo_setenv == nil {
+		return
+	}
+	arg := [2]unsafe.Pointer{cstring(k), cstring(v)}
+	asmcgocall(_cgo_setenv, unsafe.Pointer(&arg))
+}
+
+// Update the C environment if cgo is loaded.
+// Called from syscall.unsetenv.
+//
+//go:linkname syscall_unsetenv_c syscall.unsetenv_c
+func syscall_unsetenv_c(k string) {
+	if _cgo_unsetenv == nil {
+		return
+	}
+	arg := [1]unsafe.Pointer{cstring(k)}
+	asmcgocall(_cgo_unsetenv, unsafe.Pointer(&arg))
+}
+
+func cstring(s string) unsafe.Pointer {
+	p := make([]byte, len(s)+1)
+	copy(p, s)
+	return unsafe.Pointer(&p[0])
+}
diff --git a/contrib/go/_std_1.19/src/runtime/error.go b/contrib/go/_std_1.19/src/runtime/error.go
new file mode 100644
index 0000000000..b11473c634
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/error.go
@@ -0,0 +1,330 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import "internal/bytealg"
+
+// The Error interface identifies a run time error.
+type Error interface {
+	error
+
+	// RuntimeError is a no-op function but
+	// serves to distinguish types that are run time
+	// errors from ordinary errors: a type is a
+	// run time error if it has a RuntimeError method.
+	RuntimeError()
+}
+
+// A TypeAssertionError explains a failed type assertion.
+type TypeAssertionError struct {
+	_interface    *_type
+	concrete      *_type
+	asserted      *_type
+	missingMethod string // one method needed by Interface, missing from Concrete
+}
+
+func (*TypeAssertionError) RuntimeError() {}
+
+func (e *TypeAssertionError) Error() string {
+	inter := "interface"
+	if e._interface != nil {
+		inter = e._interface.string()
+	}
+	as := e.asserted.string()
+	if e.concrete == nil {
+		return "interface conversion: " + inter + " is nil, not " + as
+	}
+	cs := e.concrete.string()
+	if e.missingMethod == "" {
+		msg := "interface conversion: " + inter + " is " + cs + ", not " + as
+		if cs == as {
+			// provide slightly clearer error message
+			if e.concrete.pkgpath() != e.asserted.pkgpath() {
+				msg += " (types from different packages)"
+			} else {
+				msg += " (types from different scopes)"
+			}
+		}
+		return msg
+	}
+	return "interface conversion: " + cs + " is not " + as +
+		": missing method " + e.missingMethod
+}
+
+// itoa converts val to a decimal representation. The result is
+// written somewhere within buf and the location of the result is returned.
+// buf must be at least 20 bytes.
+//
+//go:nosplit
+func itoa(buf []byte, val uint64) []byte {
+	i := len(buf) - 1
+	for val >= 10 {
+		buf[i] = byte(val%10 + '0')
+		i--
+		val /= 10
+	}
+	buf[i] = byte(val + '0')
+	return buf[i:]
+}
+
+// An errorString represents a runtime error described by a single string.
+type errorString string
+
+func (e errorString) RuntimeError() {}
+
+func (e errorString) Error() string {
+	return "runtime error: " + string(e)
+}
+
+type errorAddressString struct {
+	msg  string  // error message
+	addr uintptr // memory address where the error occurred
+}
+
+func (e errorAddressString) RuntimeError() {}
+
+func (e errorAddressString) Error() string {
+	return "runtime error: " + e.msg
+}
+
+// Addr returns the memory address where a fault occurred.
+// The address provided is best-effort.
+// The veracity of the result may depend on the platform.
+// Errors providing this method will only be returned as
+// a result of using runtime/debug.SetPanicOnFault.
+func (e errorAddressString) Addr() uintptr {
+	return e.addr
+}
+
+// plainError represents a runtime error described a string without
+// the prefix "runtime error: " after invoking errorString.Error().
+// See Issue #14965.
+type plainError string
+
+func (e plainError) RuntimeError() {}
+
+func (e plainError) Error() string {
+	return string(e)
+}
+
+// A boundsError represents an indexing or slicing operation gone wrong.
+type boundsError struct {
+	x int64
+	y int
+	// Values in an index or slice expression can be signed or unsigned.
+	// That means we'd need 65 bits to encode all possible indexes, from -2^63 to 2^64-1.
+	// Instead, we keep track of whether x should be interpreted as signed or unsigned.
+	// y is known to be nonnegative and to fit in an int.
+	signed bool
+	code   boundsErrorCode
+}
+
+type boundsErrorCode uint8
+
+const (
+	boundsIndex boundsErrorCode = iota // s[x], 0 <= x < len(s) failed
+
+	boundsSliceAlen // s[?:x], 0 <= x <= len(s) failed
+	boundsSliceAcap // s[?:x], 0 <= x <= cap(s) failed
+	boundsSliceB    // s[x:y], 0 <= x <= y failed (but boundsSliceA didn't happen)
+
+	boundsSlice3Alen // s[?:?:x], 0 <= x <= len(s) failed
+	boundsSlice3Acap // s[?:?:x], 0 <= x <= cap(s) failed
+	boundsSlice3B    // s[?:x:y], 0 <= x <= y failed (but boundsSlice3A didn't happen)
+	boundsSlice3C    // s[x:y:?], 0 <= x <= y failed (but boundsSlice3A/B didn't happen)
+
+	boundsConvert // (*[x]T)(s), 0 <= x <= len(s) failed
+	// Note: in the above, len(s) and cap(s) are stored in y
+)
+
+// boundsErrorFmts provide error text for various out-of-bounds panics.
+// Note: if you change these strings, you should adjust the size of the buffer
+// in boundsError.Error below as well.
+var boundsErrorFmts = [...]string{
+	boundsIndex:      "index out of range [%x] with length %y",
+	boundsSliceAlen:  "slice bounds out of range [:%x] with length %y",
+	boundsSliceAcap:  "slice bounds out of range [:%x] with capacity %y",
+	boundsSliceB:     "slice bounds out of range [%x:%y]",
+	boundsSlice3Alen: "slice bounds out of range [::%x] with length %y",
+	boundsSlice3Acap: "slice bounds out of range [::%x] with capacity %y",
+	boundsSlice3B:    "slice bounds out of range [:%x:%y]",
+	boundsSlice3C:    "slice bounds out of range [%x:%y:]",
+	boundsConvert:    "cannot convert slice with length %y to pointer to array with length %x",
+}
+
+// boundsNegErrorFmts are overriding formats if x is negative. In this case there's no need to report y.
+var boundsNegErrorFmts = [...]string{
+	boundsIndex:      "index out of range [%x]",
+	boundsSliceAlen:  "slice bounds out of range [:%x]",
+	boundsSliceAcap:  "slice bounds out of range [:%x]",
+	boundsSliceB:     "slice bounds out of range [%x:]",
+	boundsSlice3Alen: "slice bounds out of range [::%x]",
+	boundsSlice3Acap: "slice bounds out of range [::%x]",
+	boundsSlice3B:    "slice bounds out of range [:%x:]",
+	boundsSlice3C:    "slice bounds out of range [%x::]",
+}
+
+func (e boundsError) RuntimeError() {}
+
+func appendIntStr(b []byte, v int64, signed bool) []byte {
+	if signed && v < 0 {
+		b = append(b, '-')
+		v = -v
+	}
+	var buf [20]byte
+	b = append(b, itoa(buf[:], uint64(v))...)
+	return b
+}
+
+func (e boundsError) Error() string {
+	fmt := boundsErrorFmts[e.code]
+	if e.signed && e.x < 0 {
+		fmt = boundsNegErrorFmts[e.code]
+	}
+	// max message length is 99: "runtime error: slice bounds out of range [::%x] with capacity %y"
+	// x can be at most 20 characters. y can be at most 19.
+	b := make([]byte, 0, 100)
+	b = append(b, "runtime error: "...)
+	for i := 0; i < len(fmt); i++ {
+		c := fmt[i]
+		if c != '%' {
+			b = append(b, c)
+			continue
+		}
+		i++
+		switch fmt[i] {
+		case 'x':
+			b = appendIntStr(b, e.x, e.signed)
+		case 'y':
+			b = appendIntStr(b, int64(e.y), true)
+		}
+	}
+	return string(b)
+}
+
+type stringer interface {
+	String() string
+}
+
+// printany prints an argument passed to panic.
+// If panic is called with a value that has a String or Error method,
+// it has already been converted into a string by preprintpanics.
+func printany(i any) {
+	switch v := i.(type) {
+	case nil:
+		print("nil")
+	case bool:
+		print(v)
+	case int:
+		print(v)
+	case int8:
+		print(v)
+	case int16:
+		print(v)
+	case int32:
+		print(v)
+	case int64:
+		print(v)
+	case uint:
+		print(v)
+	case uint8:
+		print(v)
+	case uint16:
+		print(v)
+	case uint32:
+		print(v)
+	case uint64:
+		print(v)
+	case uintptr:
+		print(v)
+	case float32:
+		print(v)
+	case float64:
+		print(v)
+	case complex64:
+		print(v)
+	case complex128:
+		print(v)
+	case string:
+		print(v)
+	default:
+		printanycustomtype(i)
+	}
+}
+
+func printanycustomtype(i any) {
+	eface := efaceOf(&i)
+	typestring := eface._type.string()
+
+	switch eface._type.kind {
+	case kindString:
+		print(typestring, `("`, *(*string)(eface.data), `")`)
+	case kindBool:
+		print(typestring, "(", *(*bool)(eface.data), ")")
+	case kindInt:
+		print(typestring, "(", *(*int)(eface.data), ")")
+	case kindInt8:
+		print(typestring, "(", *(*int8)(eface.data), ")")
+	case kindInt16:
+		print(typestring, "(", *(*int16)(eface.data), ")")
+	case kindInt32:
+		print(typestring, "(", *(*int32)(eface.data), ")")
+	case kindInt64:
+		print(typestring, "(", *(*int64)(eface.data), ")")
+	case kindUint:
+		print(typestring, "(", *(*uint)(eface.data), ")")
+	case kindUint8:
+		print(typestring, "(", *(*uint8)(eface.data), ")")
+	case kindUint16:
+		print(typestring, "(", *(*uint16)(eface.data), ")")
+	case kindUint32:
+		print(typestring, "(", *(*uint32)(eface.data), ")")
+	case kindUint64:
+		print(typestring, "(", *(*uint64)(eface.data), ")")
+	case kindUintptr:
+		print(typestring, "(", *(*uintptr)(eface.data), ")")
+	case kindFloat32:
+		print(typestring, "(", *(*float32)(eface.data), ")")
+	case kindFloat64:
+		print(typestring, "(", *(*float64)(eface.data), ")")
+	case kindComplex64:
+		print(typestring, *(*complex64)(eface.data))
+	case kindComplex128:
+		print(typestring, *(*complex128)(eface.data))
+	default:
+		print("(", typestring, ") ", eface.data)
+	}
+}
+
+// panicwrap generates a panic for a call to a wrapped value method
+// with a nil pointer receiver.
+//
+// It is called from the generated wrapper code.
+func panicwrap() {
+	pc := getcallerpc()
+	name := funcname(findfunc(pc))
+	// name is something like "main.(*T).F".
+	// We want to extract pkg ("main"), typ ("T"), and meth ("F").
+	// Do it by finding the parens.
+	i := bytealg.IndexByteString(name, '(')
+	if i < 0 {
+		throw("panicwrap: no ( in " + name)
+	}
+	pkg := name[:i-1]
+	if i+2 >= len(name) || name[i-1:i+2] != ".(*" {
+		throw("panicwrap: unexpected string after package name: " + name)
+	}
+	name = name[i+2:]
+	i = bytealg.IndexByteString(name, ')')
+	if i < 0 {
+		throw("panicwrap: no ) in " + name)
+	}
+	if i+2 >= len(name) || name[i:i+2] != ")." {
+		throw("panicwrap: unexpected string after type name: " + name)
+	}
+	typ := name[:i]
+	meth := name[i+2:]
+	panic(plainError("value method " + pkg + "." + typ + "." + meth + " called using nil *" + typ + " pointer"))
+}
diff --git a/contrib/go/_std_1.19/src/runtime/extern.go b/contrib/go/_std_1.19/src/runtime/extern.go
new file mode 100644
index 0000000000..15c519d233
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/extern.go
@@ -0,0 +1,287 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package runtime contains operations that interact with Go's runtime system,
+such as functions to control goroutines. It also includes the low-level type information
+used by the reflect package; see reflect's documentation for the programmable
+interface to the run-time type system.
+
+# Environment Variables
+
+The following environment variables ($name or %name%, depending on the host
+operating system) control the run-time behavior of Go programs. The meanings
+and use may change from release to release.
+
+The GOGC variable sets the initial garbage collection target percentage.
+A collection is triggered when the ratio of freshly allocated data to live data
+remaining after the previous collection reaches this percentage. The default
+is GOGC=100. Setting GOGC=off disables the garbage collector entirely.
+[runtime/debug.SetGCPercent] allows changing this percentage at run time.
+
+The GOMEMLIMIT variable sets a soft memory limit for the runtime. This memory limit
+includes the Go heap and all other memory managed by the runtime, and excludes
+external memory sources such as mappings of the binary itself, memory managed in
+other languages, and memory held by the operating system on behalf of the Go
+program. GOMEMLIMIT is a numeric value in bytes with an optional unit suffix.
+The supported suffixes include B, KiB, MiB, GiB, and TiB. These suffixes
+represent quantities of bytes as defined by the IEC 80000-13 standard. That is,
+they are based on powers of two: KiB means 2^10 bytes, MiB means 2^20 bytes,
+and so on. The default setting is math.MaxInt64, which effectively disables the
+memory limit. [runtime/debug.SetMemoryLimit] allows changing this limit at run
+time.
+
+The GODEBUG variable controls debugging variables within the runtime.
+It is a comma-separated list of name=val pairs setting these named variables:
+
+	allocfreetrace: setting allocfreetrace=1 causes every allocation to be
+	profiled and a stack trace printed on each object's allocation and free.
+
+	clobberfree: setting clobberfree=1 causes the garbage collector to
+	clobber the memory content of an object with bad content when it frees
+	the object.
+
+	cgocheck: setting cgocheck=0 disables all checks for packages
+	using cgo to incorrectly pass Go pointers to non-Go code.
+	Setting cgocheck=1 (the default) enables relatively cheap
+	checks that may miss some errors.  Setting cgocheck=2 enables
+	expensive checks that should not miss any errors, but will
+	cause your program to run slower.
+
+	efence: setting efence=1 causes the allocator to run in a mode
+	where each object is allocated on a unique page and addresses are
+	never recycled.
+
+	gccheckmark: setting gccheckmark=1 enables verification of the
+	garbage collector's concurrent mark phase by performing a
+	second mark pass while the world is stopped.  If the second
+	pass finds a reachable object that was not found by concurrent
+	mark, the garbage collector will panic.
+
+	gcpacertrace: setting gcpacertrace=1 causes the garbage collector to
+	print information about the internal state of the concurrent pacer.
+
+	gcshrinkstackoff: setting gcshrinkstackoff=1 disables moving goroutines
+	onto smaller stacks. In this mode, a goroutine's stack can only grow.
+
+	gcstoptheworld: setting gcstoptheworld=1 disables concurrent garbage collection,
+	making every garbage collection a stop-the-world event. Setting gcstoptheworld=2
+	also disables concurrent sweeping after the garbage collection finishes.
+
+	gctrace: setting gctrace=1 causes the garbage collector to emit a single line to standard
+	error at each collection, summarizing the amount of memory collected and the
+	length of the pause. The format of this line is subject to change.
+	Currently, it is:
+		gc # @#s #%: #+#+# ms clock, #+#/#/#+# ms cpu, #->#-># MB, # MB goal, # P
+	where the fields are as follows:
+		gc #         the GC number, incremented at each GC
+		@#s          time in seconds since program start
+		#%           percentage of time spent in GC since program start
+		#+...+#      wall-clock/CPU times for the phases of the GC
+		#->#-># MB   heap size at GC start, at GC end, and live heap
+		# MB goal    goal heap size
+		# MB stacks  estimated scannable stack size
+		# MB globals scannable global size
+		# P          number of processors used
+	The phases are stop-the-world (STW) sweep termination, concurrent
+	mark and scan, and STW mark termination. The CPU times
+	for mark/scan are broken down in to assist time (GC performed in
+	line with allocation), background GC time, and idle GC time.
+	If the line ends with "(forced)", this GC was forced by a
+	runtime.GC() call.
+
+	harddecommit: setting harddecommit=1 causes memory that is returned to the OS to
+	also have protections removed on it. This is the only mode of operation on Windows,
+	but is helpful in debugging scavenger-related issues on other platforms. Currently,
+	only supported on Linux.
+
+	inittrace: setting inittrace=1 causes the runtime to emit a single line to standard
+	error for each package with init work, summarizing the execution time and memory
+	allocation. No information is printed for inits executed as part of plugin loading
+	and for packages without both user defined and compiler generated init work.
+	The format of this line is subject to change. Currently, it is:
+		init # @#ms, # ms clock, # bytes, # allocs
+	where the fields are as follows:
+		init #      the package name
+		@# ms       time in milliseconds when the init started since program start
+		# clock     wall-clock time for package initialization work
+		# bytes     memory allocated on the heap
+		# allocs    number of heap allocations
+
+	madvdontneed: setting madvdontneed=0 will use MADV_FREE
+	instead of MADV_DONTNEED on Linux when returning memory to the
+	kernel. This is more efficient, but means RSS numbers will
+	drop only when the OS is under memory pressure.
+
+	memprofilerate: setting memprofilerate=X will update the value of runtime.MemProfileRate.
+	When set to 0 memory profiling is disabled.  Refer to the description of
+	MemProfileRate for the default value.
+
+	invalidptr: invalidptr=1 (the default) causes the garbage collector and stack
+	copier to crash the program if an invalid pointer value (for example, 1)
+	is found in a pointer-typed location. Setting invalidptr=0 disables this check.
+	This should only be used as a temporary workaround to diagnose buggy code.
+	The real fix is to not store integers in pointer-typed locations.
+
+	sbrk: setting sbrk=1 replaces the memory allocator and garbage collector
+	with a trivial allocator that obtains memory from the operating system and
+	never reclaims any memory.
+
+	scavtrace: setting scavtrace=1 causes the runtime to emit a single line to standard
+	error, roughly once per GC cycle, summarizing the amount of work done by the
+	scavenger as well as the total amount of memory returned to the operating system
+	and an estimate of physical memory utilization. The format of this line is subject
+	to change, but currently it is:
+		scav # KiB work, # KiB total, #% util
+	where the fields are as follows:
+		# KiB work   the amount of memory returned to the OS since the last line
+		# KiB total  the total amount of memory returned to the OS
+		#% util      the fraction of all unscavenged memory which is in-use
+	If the line ends with "(forced)", then scavenging was forced by a
+	debug.FreeOSMemory() call.
+
+	scheddetail: setting schedtrace=X and scheddetail=1 causes the scheduler to emit
+	detailed multiline info every X milliseconds, describing state of the scheduler,
+	processors, threads and goroutines.
+
+	schedtrace: setting schedtrace=X causes the scheduler to emit a single line to standard
+	error every X milliseconds, summarizing the scheduler state.
+
+	tracebackancestors: setting tracebackancestors=N extends tracebacks with the stacks at
+	which goroutines were created, where N limits the number of ancestor goroutines to
+	report. This also extends the information returned by runtime.Stack. Ancestor's goroutine
+	IDs will refer to the ID of the goroutine at the time of creation; it's possible for this
+	ID to be reused for another goroutine. Setting N to 0 will report no ancestry information.
+
+	asyncpreemptoff: asyncpreemptoff=1 disables signal-based
+	asynchronous goroutine preemption. This makes some loops
+	non-preemptible for long periods, which may delay GC and
+	goroutine scheduling. This is useful for debugging GC issues
+	because it also disables the conservative stack scanning used
+	for asynchronously preempted goroutines.
+
+The net and net/http packages also refer to debugging variables in GODEBUG.
+See the documentation for those packages for details.
+
+The GOMAXPROCS variable limits the number of operating system threads that
+can execute user-level Go code simultaneously. There is no limit to the number of threads
+that can be blocked in system calls on behalf of Go code; those do not count against
+the GOMAXPROCS limit. This package's GOMAXPROCS function queries and changes
+the limit.
+
+The GORACE variable configures the race detector, for programs built using -race.
+See https://golang.org/doc/articles/race_detector.html for details.
+
+The GOTRACEBACK variable controls the amount of output generated when a Go
+program fails due to an unrecovered panic or an unexpected runtime condition.
+By default, a failure prints a stack trace for the current goroutine,
+eliding functions internal to the run-time system, and then exits with exit code 2.
+The failure prints stack traces for all goroutines if there is no current goroutine
+or the failure is internal to the run-time.
+GOTRACEBACK=none omits the goroutine stack traces entirely.
+GOTRACEBACK=single (the default) behaves as described above.
+GOTRACEBACK=all adds stack traces for all user-created goroutines.
+GOTRACEBACK=system is like “all” but adds stack frames for run-time functions
+and shows goroutines created internally by the run-time.
+GOTRACEBACK=crash is like “system” but crashes in an operating system-specific
+manner instead of exiting. For example, on Unix systems, the crash raises
+SIGABRT to trigger a core dump.
+For historical reasons, the GOTRACEBACK settings 0, 1, and 2 are synonyms for
+none, all, and system, respectively.
+The runtime/debug package's SetTraceback function allows increasing the
+amount of output at run time, but it cannot reduce the amount below that
+specified by the environment variable.
+See https://golang.org/pkg/runtime/debug/#SetTraceback.
+
+The GOARCH, GOOS, GOPATH, and GOROOT environment variables complete
+the set of Go environment variables. They influence the building of Go programs
+(see https://golang.org/cmd/go and https://golang.org/pkg/go/build).
+GOARCH, GOOS, and GOROOT are recorded at compile time and made available by
+constants or functions in this package, but they do not influence the execution
+of the run-time system.
+*/
+package runtime
+
+import (
+	"internal/goarch"
+	"internal/goos"
+)
+
+// Caller reports file and line number information about function invocations on
+// the calling goroutine's stack. The argument skip is the number of stack frames
+// to ascend, with 0 identifying the caller of Caller.  (For historical reasons the
+// meaning of skip differs between Caller and Callers.) The return values report the
+// program counter, file name, and line number within the file of the corresponding
+// call. The boolean ok is false if it was not possible to recover the information.
+func Caller(skip int) (pc uintptr, file string, line int, ok bool) {
+	rpc := make([]uintptr, 1)
+	n := callers(skip+1, rpc[:])
+	if n < 1 {
+		return
+	}
+	frame, _ := CallersFrames(rpc).Next()
+	return frame.PC, frame.File, frame.Line, frame.PC != 0
+}
+
+// Callers fills the slice pc with the return program counters of function invocations
+// on the calling goroutine's stack. The argument skip is the number of stack frames
+// to skip before recording in pc, with 0 identifying the frame for Callers itself and
+// 1 identifying the caller of Callers.
+// It returns the number of entries written to pc.
+//
+// To translate these PCs into symbolic information such as function
+// names and line numbers, use CallersFrames. CallersFrames accounts
+// for inlined functions and adjusts the return program counters into
+// call program counters. Iterating over the returned slice of PCs
+// directly is discouraged, as is using FuncForPC on any of the
+// returned PCs, since these cannot account for inlining or return
+// program counter adjustment.
+func Callers(skip int, pc []uintptr) int {
+	// runtime.callers uses pc.array==nil as a signal
+	// to print a stack trace. Pick off 0-length pc here
+	// so that we don't let a nil pc slice get to it.
+	if len(pc) == 0 {
+		return 0
+	}
+	return callers(skip, pc)
+}
+
+var defaultGOROOT string // set by cmd/link
+
+// GOROOT returns the root of the Go tree. It uses the
+// GOROOT environment variable, if set at process start,
+// or else the root used during the Go build.
+func GOROOT() string {
+	s := gogetenv("GOROOT")
+	if s != "" {
+		return s
+	}
+	return defaultGOROOT
+}
+
+// buildVersion is the Go tree's version string at build time.
+//
+// If any GOEXPERIMENTs are set to non-default values, it will include
+// "X:<GOEXPERIMENT>".
+//
+// This is set by the linker.
+//
+// This is accessed by "go version <binary>".
+var buildVersion string
+
+// Version returns the Go tree's version string.
+// It is either the commit hash and date at the time of the build or,
+// when possible, a release tag like "go1.3".
+func Version() string {
+	return buildVersion
+}
+
+// GOOS is the running program's operating system target:
+// one of darwin, freebsd, linux, and so on.
+// To view possible combinations of GOOS and GOARCH, run "go tool dist list".
+const GOOS string = goos.GOOS
+
+// GOARCH is the running program's architecture target:
+// one of 386, amd64, arm, s390x, and so on.
+const GOARCH string = goarch.GOARCH
diff --git a/contrib/go/_std_1.18/src/runtime/fastlog2.go b/contrib/go/_std_1.19/src/runtime/fastlog2.go
index 1f251bfaab..1f251bfaab 100644
--- a/contrib/go/_std_1.18/src/runtime/fastlog2.go
+++ b/contrib/go/_std_1.19/src/runtime/fastlog2.go
diff --git a/contrib/go/_std_1.18/src/runtime/fastlog2table.go b/contrib/go/_std_1.19/src/runtime/fastlog2table.go
index 6ba4a7d3f2..6ba4a7d3f2 100644
--- a/contrib/go/_std_1.18/src/runtime/fastlog2table.go
+++ b/contrib/go/_std_1.19/src/runtime/fastlog2table.go
diff --git a/contrib/go/_std_1.19/src/runtime/float.go b/contrib/go/_std_1.19/src/runtime/float.go
new file mode 100644
index 0000000000..c80c8b7abf
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/float.go
@@ -0,0 +1,54 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import "unsafe"
+
+var inf = float64frombits(0x7FF0000000000000)
+
+// isNaN reports whether f is an IEEE 754 “not-a-number” value.
+func isNaN(f float64) (is bool) {
+	// IEEE 754 says that only NaNs satisfy f != f.
+	return f != f
+}
+
+// isFinite reports whether f is neither NaN nor an infinity.
+func isFinite(f float64) bool {
+	return !isNaN(f - f)
+}
+
+// isInf reports whether f is an infinity.
+func isInf(f float64) bool {
+	return !isNaN(f) && !isFinite(f)
+}
+
+// Abs returns the absolute value of x.
+//
+// Special cases are:
+//
+//	Abs(±Inf) = +Inf
+//	Abs(NaN) = NaN
+func abs(x float64) float64 {
+	const sign = 1 << 63
+	return float64frombits(float64bits(x) &^ sign)
+}
+
+// copysign returns a value with the magnitude
+// of x and the sign of y.
+func copysign(x, y float64) float64 {
+	const sign = 1 << 63
+	return float64frombits(float64bits(x)&^sign | float64bits(y)&sign)
+}
+
+// Float64bits returns the IEEE 754 binary representation of f.
+func float64bits(f float64) uint64 {
+	return *(*uint64)(unsafe.Pointer(&f))
+}
+
+// Float64frombits returns the floating point number corresponding
+// the IEEE 754 binary representation b.
+func float64frombits(b uint64) float64 {
+	return *(*float64)(unsafe.Pointer(&b))
+}
diff --git a/contrib/go/_std_1.18/src/runtime/funcdata.h b/contrib/go/_std_1.19/src/runtime/funcdata.h
index 2e2bb30446..2e2bb30446 100644
--- a/contrib/go/_std_1.18/src/runtime/funcdata.h
+++ b/contrib/go/_std_1.19/src/runtime/funcdata.h
diff --git a/contrib/go/_std_1.18/src/runtime/go_tls.h b/contrib/go/_std_1.19/src/runtime/go_tls.h
index a47e798d9d..a47e798d9d 100644
--- a/contrib/go/_std_1.18/src/runtime/go_tls.h
+++ b/contrib/go/_std_1.19/src/runtime/go_tls.h
diff --git a/contrib/go/_std_1.19/src/runtime/hash64.go b/contrib/go/_std_1.19/src/runtime/hash64.go
new file mode 100644
index 0000000000..2864a4b963
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/hash64.go
@@ -0,0 +1,92 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Hashing algorithm inspired by
+// wyhash: https://github.com/wangyi-fudan/wyhash
+
+//go:build amd64 || arm64 || loong64 || mips64 || mips64le || ppc64 || ppc64le || riscv64 || s390x || wasm
+
+package runtime
+
+import (
+	"runtime/internal/math"
+	"unsafe"
+)
+
+const (
+	m1 = 0xa0761d6478bd642f
+	m2 = 0xe7037ed1a0b428db
+	m3 = 0x8ebc6af09c88c6e3
+	m4 = 0x589965cc75374cc3
+	m5 = 0x1d8e4e27c47d124f
+)
+
+func memhashFallback(p unsafe.Pointer, seed, s uintptr) uintptr {
+	var a, b uintptr
+	seed ^= hashkey[0] ^ m1
+	switch {
+	case s == 0:
+		return seed
+	case s < 4:
+		a = uintptr(*(*byte)(p))
+		a |= uintptr(*(*byte)(add(p, s>>1))) << 8
+		a |= uintptr(*(*byte)(add(p, s-1))) << 16
+	case s == 4:
+		a = r4(p)
+		b = a
+	case s < 8:
+		a = r4(p)
+		b = r4(add(p, s-4))
+	case s == 8:
+		a = r8(p)
+		b = a
+	case s <= 16:
+		a = r8(p)
+		b = r8(add(p, s-8))
+	default:
+		l := s
+		if l > 48 {
+			seed1 := seed
+			seed2 := seed
+			for ; l > 48; l -= 48 {
+				seed = mix(r8(p)^m2, r8(add(p, 8))^seed)
+				seed1 = mix(r8(add(p, 16))^m3, r8(add(p, 24))^seed1)
+				seed2 = mix(r8(add(p, 32))^m4, r8(add(p, 40))^seed2)
+				p = add(p, 48)
+			}
+			seed ^= seed1 ^ seed2
+		}
+		for ; l > 16; l -= 16 {
+			seed = mix(r8(p)^m2, r8(add(p, 8))^seed)
+			p = add(p, 16)
+		}
+		a = r8(add(p, l-16))
+		b = r8(add(p, l-8))
+	}
+
+	return mix(m5^s, mix(a^m2, b^seed))
+}
+
+func memhash32Fallback(p unsafe.Pointer, seed uintptr) uintptr {
+	a := r4(p)
+	return mix(m5^4, mix(a^m2, a^seed^hashkey[0]^m1))
+}
+
+func memhash64Fallback(p unsafe.Pointer, seed uintptr) uintptr {
+	a := r8(p)
+	return mix(m5^8, mix(a^m2, a^seed^hashkey[0]^m1))
+}
+
+func mix(a, b uintptr) uintptr {
+	hi, lo := math.Mul64(uint64(a), uint64(b))
+	return uintptr(hi ^ lo)
+}
+
+func r4(p unsafe.Pointer) uintptr {
+	return uintptr(readUnaligned32(p))
+}
+
+func r8(p unsafe.Pointer) uintptr {
+	return uintptr(readUnaligned64(p))
+}
diff --git a/contrib/go/_std_1.19/src/runtime/heapdump.go b/contrib/go/_std_1.19/src/runtime/heapdump.go
new file mode 100644
index 0000000000..c7f2b7a443
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/heapdump.go
@@ -0,0 +1,752 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Implementation of runtime/debug.WriteHeapDump. Writes all
+// objects in the heap plus additional info (roots, threads,
+// finalizers, etc.) to a file.
+
+// The format of the dumped file is described at
+// https://golang.org/s/go15heapdump.
+
+package runtime
+
+import (
+	"internal/goarch"
+	"unsafe"
+)
+
+//go:linkname runtime_debug_WriteHeapDump runtime/debug.WriteHeapDump
+func runtime_debug_WriteHeapDump(fd uintptr) {
+	stopTheWorld("write heap dump")
+
+	// Keep m on this G's stack instead of the system stack.
+	// Both readmemstats_m and writeheapdump_m have pretty large
+	// peak stack depths and we risk blowing the system stack.
+	// This is safe because the world is stopped, so we don't
+	// need to worry about anyone shrinking and therefore moving
+	// our stack.
+	var m MemStats
+	systemstack(func() {
+		// Call readmemstats_m here instead of deeper in
+		// writeheapdump_m because we might blow the system stack
+		// otherwise.
+		readmemstats_m(&m)
+		writeheapdump_m(fd, &m)
+	})
+
+	startTheWorld()
+}
+
+const (
+	fieldKindEol       = 0
+	fieldKindPtr       = 1
+	fieldKindIface     = 2
+	fieldKindEface     = 3
+	tagEOF             = 0
+	tagObject          = 1
+	tagOtherRoot       = 2
+	tagType            = 3
+	tagGoroutine       = 4
+	tagStackFrame      = 5
+	tagParams          = 6
+	tagFinalizer       = 7
+	tagItab            = 8
+	tagOSThread        = 9
+	tagMemStats        = 10
+	tagQueuedFinalizer = 11
+	tagData            = 12
+	tagBSS             = 13
+	tagDefer           = 14
+	tagPanic           = 15
+	tagMemProf         = 16
+	tagAllocSample     = 17
+)
+
+var dumpfd uintptr // fd to write the dump to.
+var tmpbuf []byte
+
+// buffer of pending write data
+const (
+	bufSize = 4096
+)
+
+var buf [bufSize]byte
+var nbuf uintptr
+
+func dwrite(data unsafe.Pointer, len uintptr) {
+	if len == 0 {
+		return
+	}
+	if nbuf+len <= bufSize {
+		copy(buf[nbuf:], (*[bufSize]byte)(data)[:len])
+		nbuf += len
+		return
+	}
+
+	write(dumpfd, unsafe.Pointer(&buf), int32(nbuf))
+	if len >= bufSize {
+		write(dumpfd, data, int32(len))
+		nbuf = 0
+	} else {
+		copy(buf[:], (*[bufSize]byte)(data)[:len])
+		nbuf = len
+	}
+}
+
+func dwritebyte(b byte) {
+	dwrite(unsafe.Pointer(&b), 1)
+}
+
+func flush() {
+	write(dumpfd, unsafe.Pointer(&buf), int32(nbuf))
+	nbuf = 0
+}
+
+// Cache of types that have been serialized already.
+// We use a type's hash field to pick a bucket.
+// Inside a bucket, we keep a list of types that
+// have been serialized so far, most recently used first.
+// Note: when a bucket overflows we may end up
+// serializing a type more than once. That's ok.
+const (
+	typeCacheBuckets = 256
+	typeCacheAssoc   = 4
+)
+
+type typeCacheBucket struct {
+	t [typeCacheAssoc]*_type
+}
+
+var typecache [typeCacheBuckets]typeCacheBucket
+
+// dump a uint64 in a varint format parseable by encoding/binary
+func dumpint(v uint64) {
+	var buf [10]byte
+	var n int
+	for v >= 0x80 {
+		buf[n] = byte(v | 0x80)
+		n++
+		v >>= 7
+	}
+	buf[n] = byte(v)
+	n++
+	dwrite(unsafe.Pointer(&buf), uintptr(n))
+}
+
+func dumpbool(b bool) {
+	if b {
+		dumpint(1)
+	} else {
+		dumpint(0)
+	}
+}
+
+// dump varint uint64 length followed by memory contents
+func dumpmemrange(data unsafe.Pointer, len uintptr) {
+	dumpint(uint64(len))
+	dwrite(data, len)
+}
+
+func dumpslice(b []byte) {
+	dumpint(uint64(len(b)))
+	if len(b) > 0 {
+		dwrite(unsafe.Pointer(&b[0]), uintptr(len(b)))
+	}
+}
+
+func dumpstr(s string) {
+	sp := stringStructOf(&s)
+	dumpmemrange(sp.str, uintptr(sp.len))
+}
+
+// dump information for a type
+func dumptype(t *_type) {
+	if t == nil {
+		return
+	}
+
+	// If we've definitely serialized the type before,
+	// no need to do it again.
+	b := &typecache[t.hash&(typeCacheBuckets-1)]
+	if t == b.t[0] {
+		return
+	}
+	for i := 1; i < typeCacheAssoc; i++ {
+		if t == b.t[i] {
+			// Move-to-front
+			for j := i; j > 0; j-- {
+				b.t[j] = b.t[j-1]
+			}
+			b.t[0] = t
+			return
+		}
+	}
+
+	// Might not have been dumped yet. Dump it and
+	// remember we did so.
+	for j := typeCacheAssoc - 1; j > 0; j-- {
+		b.t[j] = b.t[j-1]
+	}
+	b.t[0] = t
+
+	// dump the type
+	dumpint(tagType)
+	dumpint(uint64(uintptr(unsafe.Pointer(t))))
+	dumpint(uint64(t.size))
+	if x := t.uncommon(); x == nil || t.nameOff(x.pkgpath).name() == "" {
+		dumpstr(t.string())
+	} else {
+		pkgpathstr := t.nameOff(x.pkgpath).name()
+		pkgpath := stringStructOf(&pkgpathstr)
+		namestr := t.name()
+		name := stringStructOf(&namestr)
+		dumpint(uint64(uintptr(pkgpath.len) + 1 + uintptr(name.len)))
+		dwrite(pkgpath.str, uintptr(pkgpath.len))
+		dwritebyte('.')
+		dwrite(name.str, uintptr(name.len))
+	}
+	dumpbool(t.kind&kindDirectIface == 0 || t.ptrdata != 0)
+}
+
+// dump an object
+func dumpobj(obj unsafe.Pointer, size uintptr, bv bitvector) {
+	dumpint(tagObject)
+	dumpint(uint64(uintptr(obj)))
+	dumpmemrange(obj, size)
+	dumpfields(bv)
+}
+
+func dumpotherroot(description string, to unsafe.Pointer) {
+	dumpint(tagOtherRoot)
+	dumpstr(description)
+	dumpint(uint64(uintptr(to)))
+}
+
+func dumpfinalizer(obj unsafe.Pointer, fn *funcval, fint *_type, ot *ptrtype) {
+	dumpint(tagFinalizer)
+	dumpint(uint64(uintptr(obj)))
+	dumpint(uint64(uintptr(unsafe.Pointer(fn))))
+	dumpint(uint64(uintptr(unsafe.Pointer(fn.fn))))
+	dumpint(uint64(uintptr(unsafe.Pointer(fint))))
+	dumpint(uint64(uintptr(unsafe.Pointer(ot))))
+}
+
+type childInfo struct {
+	// Information passed up from the callee frame about
+	// the layout of the outargs region.
+	argoff uintptr   // where the arguments start in the frame
+	arglen uintptr   // size of args region
+	args   bitvector // if args.n >= 0, pointer map of args region
+	sp     *uint8    // callee sp
+	depth  uintptr   // depth in call stack (0 == most recent)
+}
+
+// dump kinds & offsets of interesting fields in bv
+func dumpbv(cbv *bitvector, offset uintptr) {
+	for i := uintptr(0); i < uintptr(cbv.n); i++ {
+		if cbv.ptrbit(i) == 1 {
+			dumpint(fieldKindPtr)
+			dumpint(uint64(offset + i*goarch.PtrSize))
+		}
+	}
+}
+
+func dumpframe(s *stkframe, arg unsafe.Pointer) bool {
+	child := (*childInfo)(arg)
+	f := s.fn
+
+	// Figure out what we can about our stack map
+	pc := s.pc
+	pcdata := int32(-1) // Use the entry map at function entry
+	if pc != f.entry() {
+		pc--
+		pcdata = pcdatavalue(f, _PCDATA_StackMapIndex, pc, nil)
+	}
+	if pcdata == -1 {
+		// We do not have a valid pcdata value but there might be a
+		// stackmap for this function. It is likely that we are looking
+		// at the function prologue, assume so and hope for the best.
+		pcdata = 0
+	}
+	stkmap := (*stackmap)(funcdata(f, _FUNCDATA_LocalsPointerMaps))
+
+	var bv bitvector
+	if stkmap != nil && stkmap.n > 0 {
+		bv = stackmapdata(stkmap, pcdata)
+	} else {
+		bv.n = -1
+	}
+
+	// Dump main body of stack frame.
+	dumpint(tagStackFrame)
+	dumpint(uint64(s.sp))                              // lowest address in frame
+	dumpint(uint64(child.depth))                       // # of frames deep on the stack
+	dumpint(uint64(uintptr(unsafe.Pointer(child.sp)))) // sp of child, or 0 if bottom of stack
+	dumpmemrange(unsafe.Pointer(s.sp), s.fp-s.sp)      // frame contents
+	dumpint(uint64(f.entry()))
+	dumpint(uint64(s.pc))
+	dumpint(uint64(s.continpc))
+	name := funcname(f)
+	if name == "" {
+		name = "unknown function"
+	}
+	dumpstr(name)
+
+	// Dump fields in the outargs section
+	if child.args.n >= 0 {
+		dumpbv(&child.args, child.argoff)
+	} else {
+		// conservative - everything might be a pointer
+		for off := child.argoff; off < child.argoff+child.arglen; off += goarch.PtrSize {
+			dumpint(fieldKindPtr)
+			dumpint(uint64(off))
+		}
+	}
+
+	// Dump fields in the local vars section
+	if stkmap == nil {
+		// No locals information, dump everything.
+		for off := child.arglen; off < s.varp-s.sp; off += goarch.PtrSize {
+			dumpint(fieldKindPtr)
+			dumpint(uint64(off))
+		}
+	} else if stkmap.n < 0 {
+		// Locals size information, dump just the locals.
+		size := uintptr(-stkmap.n)
+		for off := s.varp - size - s.sp; off < s.varp-s.sp; off += goarch.PtrSize {
+			dumpint(fieldKindPtr)
+			dumpint(uint64(off))
+		}
+	} else if stkmap.n > 0 {
+		// Locals bitmap information, scan just the pointers in
+		// locals.
+		dumpbv(&bv, s.varp-uintptr(bv.n)*goarch.PtrSize-s.sp)
+	}
+	dumpint(fieldKindEol)
+
+	// Record arg info for parent.
+	child.argoff = s.argp - s.fp
+	child.arglen = s.arglen
+	child.sp = (*uint8)(unsafe.Pointer(s.sp))
+	child.depth++
+	stkmap = (*stackmap)(funcdata(f, _FUNCDATA_ArgsPointerMaps))
+	if stkmap != nil {
+		child.args = stackmapdata(stkmap, pcdata)
+	} else {
+		child.args.n = -1
+	}
+	return true
+}
+
+func dumpgoroutine(gp *g) {
+	var sp, pc, lr uintptr
+	if gp.syscallsp != 0 {
+		sp = gp.syscallsp
+		pc = gp.syscallpc
+		lr = 0
+	} else {
+		sp = gp.sched.sp
+		pc = gp.sched.pc
+		lr = gp.sched.lr
+	}
+
+	dumpint(tagGoroutine)
+	dumpint(uint64(uintptr(unsafe.Pointer(gp))))
+	dumpint(uint64(sp))
+	dumpint(uint64(gp.goid))
+	dumpint(uint64(gp.gopc))
+	dumpint(uint64(readgstatus(gp)))
+	dumpbool(isSystemGoroutine(gp, false))
+	dumpbool(false) // isbackground
+	dumpint(uint64(gp.waitsince))
+	dumpstr(gp.waitreason.String())
+	dumpint(uint64(uintptr(gp.sched.ctxt)))
+	dumpint(uint64(uintptr(unsafe.Pointer(gp.m))))
+	dumpint(uint64(uintptr(unsafe.Pointer(gp._defer))))
+	dumpint(uint64(uintptr(unsafe.Pointer(gp._panic))))
+
+	// dump stack
+	var child childInfo
+	child.args.n = -1
+	child.arglen = 0
+	child.sp = nil
+	child.depth = 0
+	gentraceback(pc, sp, lr, gp, 0, nil, 0x7fffffff, dumpframe, noescape(unsafe.Pointer(&child)), 0)
+
+	// dump defer & panic records
+	for d := gp._defer; d != nil; d = d.link {
+		dumpint(tagDefer)
+		dumpint(uint64(uintptr(unsafe.Pointer(d))))
+		dumpint(uint64(uintptr(unsafe.Pointer(gp))))
+		dumpint(uint64(d.sp))
+		dumpint(uint64(d.pc))
+		fn := *(**funcval)(unsafe.Pointer(&d.fn))
+		dumpint(uint64(uintptr(unsafe.Pointer(fn))))
+		if d.fn == nil {
+			// d.fn can be nil for open-coded defers
+			dumpint(uint64(0))
+		} else {
+			dumpint(uint64(uintptr(unsafe.Pointer(fn.fn))))
+		}
+		dumpint(uint64(uintptr(unsafe.Pointer(d.link))))
+	}
+	for p := gp._panic; p != nil; p = p.link {
+		dumpint(tagPanic)
+		dumpint(uint64(uintptr(unsafe.Pointer(p))))
+		dumpint(uint64(uintptr(unsafe.Pointer(gp))))
+		eface := efaceOf(&p.arg)
+		dumpint(uint64(uintptr(unsafe.Pointer(eface._type))))
+		dumpint(uint64(uintptr(unsafe.Pointer(eface.data))))
+		dumpint(0) // was p->defer, no longer recorded
+		dumpint(uint64(uintptr(unsafe.Pointer(p.link))))
+	}
+}
+
+func dumpgs() {
+	assertWorldStopped()
+
+	// goroutines & stacks
+	forEachG(func(gp *g) {
+		status := readgstatus(gp) // The world is stopped so gp will not be in a scan state.
+		switch status {
+		default:
+			print("runtime: unexpected G.status ", hex(status), "\n")
+			throw("dumpgs in STW - bad status")
+		case _Gdead:
+			// ok
+		case _Grunnable,
+			_Gsyscall,
+			_Gwaiting:
+			dumpgoroutine(gp)
+		}
+	})
+}
+
+func finq_callback(fn *funcval, obj unsafe.Pointer, nret uintptr, fint *_type, ot *ptrtype) {
+	dumpint(tagQueuedFinalizer)
+	dumpint(uint64(uintptr(obj)))
+	dumpint(uint64(uintptr(unsafe.Pointer(fn))))
+	dumpint(uint64(uintptr(unsafe.Pointer(fn.fn))))
+	dumpint(uint64(uintptr(unsafe.Pointer(fint))))
+	dumpint(uint64(uintptr(unsafe.Pointer(ot))))
+}
+
+func dumproots() {
+	// To protect mheap_.allspans.
+	assertWorldStopped()
+
+	// TODO(mwhudson): dump datamask etc from all objects
+	// data segment
+	dumpint(tagData)
+	dumpint(uint64(firstmoduledata.data))
+	dumpmemrange(unsafe.Pointer(firstmoduledata.data), firstmoduledata.edata-firstmoduledata.data)
+	dumpfields(firstmoduledata.gcdatamask)
+
+	// bss segment
+	dumpint(tagBSS)
+	dumpint(uint64(firstmoduledata.bss))
+	dumpmemrange(unsafe.Pointer(firstmoduledata.bss), firstmoduledata.ebss-firstmoduledata.bss)
+	dumpfields(firstmoduledata.gcbssmask)
+
+	// mspan.types
+	for _, s := range mheap_.allspans {
+		if s.state.get() == mSpanInUse {
+			// Finalizers
+			for sp := s.specials; sp != nil; sp = sp.next {
+				if sp.kind != _KindSpecialFinalizer {
+					continue
+				}
+				spf := (*specialfinalizer)(unsafe.Pointer(sp))
+				p := unsafe.Pointer(s.base() + uintptr(spf.special.offset))
+				dumpfinalizer(p, spf.fn, spf.fint, spf.ot)
+			}
+		}
+	}
+
+	// Finalizer queue
+	iterate_finq(finq_callback)
+}
+
+// Bit vector of free marks.
+// Needs to be as big as the largest number of objects per span.
+var freemark [_PageSize / 8]bool
+
+func dumpobjs() {
+	// To protect mheap_.allspans.
+	assertWorldStopped()
+
+	for _, s := range mheap_.allspans {
+		if s.state.get() != mSpanInUse {
+			continue
+		}
+		p := s.base()
+		size := s.elemsize
+		n := (s.npages << _PageShift) / size
+		if n > uintptr(len(freemark)) {
+			throw("freemark array doesn't have enough entries")
+		}
+
+		for freeIndex := uintptr(0); freeIndex < s.nelems; freeIndex++ {
+			if s.isFree(freeIndex) {
+				freemark[freeIndex] = true
+			}
+		}
+
+		for j := uintptr(0); j < n; j, p = j+1, p+size {
+			if freemark[j] {
+				freemark[j] = false
+				continue
+			}
+			dumpobj(unsafe.Pointer(p), size, makeheapobjbv(p, size))
+		}
+	}
+}
+
+func dumpparams() {
+	dumpint(tagParams)
+	x := uintptr(1)
+	if *(*byte)(unsafe.Pointer(&x)) == 1 {
+		dumpbool(false) // little-endian ptrs
+	} else {
+		dumpbool(true) // big-endian ptrs
+	}
+	dumpint(goarch.PtrSize)
+	var arenaStart, arenaEnd uintptr
+	for i1 := range mheap_.arenas {
+		if mheap_.arenas[i1] == nil {
+			continue
+		}
+		for i, ha := range mheap_.arenas[i1] {
+			if ha == nil {
+				continue
+			}
+			base := arenaBase(arenaIdx(i1)<<arenaL1Shift | arenaIdx(i))
+			if arenaStart == 0 || base < arenaStart {
+				arenaStart = base
+			}
+			if base+heapArenaBytes > arenaEnd {
+				arenaEnd = base + heapArenaBytes
+			}
+		}
+	}
+	dumpint(uint64(arenaStart))
+	dumpint(uint64(arenaEnd))
+	dumpstr(goarch.GOARCH)
+	dumpstr(buildVersion)
+	dumpint(uint64(ncpu))
+}
+
+func itab_callback(tab *itab) {
+	t := tab._type
+	dumptype(t)
+	dumpint(tagItab)
+	dumpint(uint64(uintptr(unsafe.Pointer(tab))))
+	dumpint(uint64(uintptr(unsafe.Pointer(t))))
+}
+
+func dumpitabs() {
+	iterate_itabs(itab_callback)
+}
+
+func dumpms() {
+	for mp := allm; mp != nil; mp = mp.alllink {
+		dumpint(tagOSThread)
+		dumpint(uint64(uintptr(unsafe.Pointer(mp))))
+		dumpint(uint64(mp.id))
+		dumpint(mp.procid)
+	}
+}
+
+//go:systemstack
+func dumpmemstats(m *MemStats) {
+	assertWorldStopped()
+
+	// These ints should be identical to the exported
+	// MemStats structure and should be ordered the same
+	// way too.
+	dumpint(tagMemStats)
+	dumpint(m.Alloc)
+	dumpint(m.TotalAlloc)
+	dumpint(m.Sys)
+	dumpint(m.Lookups)
+	dumpint(m.Mallocs)
+	dumpint(m.Frees)
+	dumpint(m.HeapAlloc)
+	dumpint(m.HeapSys)
+	dumpint(m.HeapIdle)
+	dumpint(m.HeapInuse)
+	dumpint(m.HeapReleased)
+	dumpint(m.HeapObjects)
+	dumpint(m.StackInuse)
+	dumpint(m.StackSys)
+	dumpint(m.MSpanInuse)
+	dumpint(m.MSpanSys)
+	dumpint(m.MCacheInuse)
+	dumpint(m.MCacheSys)
+	dumpint(m.BuckHashSys)
+	dumpint(m.GCSys)
+	dumpint(m.OtherSys)
+	dumpint(m.NextGC)
+	dumpint(m.LastGC)
+	dumpint(m.PauseTotalNs)
+	for i := 0; i < 256; i++ {
+		dumpint(m.PauseNs[i])
+	}
+	dumpint(uint64(m.NumGC))
+}
+
+func dumpmemprof_callback(b *bucket, nstk uintptr, pstk *uintptr, size, allocs, frees uintptr) {
+	stk := (*[100000]uintptr)(unsafe.Pointer(pstk))
+	dumpint(tagMemProf)
+	dumpint(uint64(uintptr(unsafe.Pointer(b))))
+	dumpint(uint64(size))
+	dumpint(uint64(nstk))
+	for i := uintptr(0); i < nstk; i++ {
+		pc := stk[i]
+		f := findfunc(pc)
+		if !f.valid() {
+			var buf [64]byte
+			n := len(buf)
+			n--
+			buf[n] = ')'
+			if pc == 0 {
+				n--
+				buf[n] = '0'
+			} else {
+				for pc > 0 {
+					n--
+					buf[n] = "0123456789abcdef"[pc&15]
+					pc >>= 4
+				}
+			}
+			n--
+			buf[n] = 'x'
+			n--
+			buf[n] = '0'
+			n--
+			buf[n] = '('
+			dumpslice(buf[n:])
+			dumpstr("?")
+			dumpint(0)
+		} else {
+			dumpstr(funcname(f))
+			if i > 0 && pc > f.entry() {
+				pc--
+			}
+			file, line := funcline(f, pc)
+			dumpstr(file)
+			dumpint(uint64(line))
+		}
+	}
+	dumpint(uint64(allocs))
+	dumpint(uint64(frees))
+}
+
+func dumpmemprof() {
+	// To protect mheap_.allspans.
+	assertWorldStopped()
+
+	iterate_memprof(dumpmemprof_callback)
+	for _, s := range mheap_.allspans {
+		if s.state.get() != mSpanInUse {
+			continue
+		}
+		for sp := s.specials; sp != nil; sp = sp.next {
+			if sp.kind != _KindSpecialProfile {
+				continue
+			}
+			spp := (*specialprofile)(unsafe.Pointer(sp))
+			p := s.base() + uintptr(spp.special.offset)
+			dumpint(tagAllocSample)
+			dumpint(uint64(p))
+			dumpint(uint64(uintptr(unsafe.Pointer(spp.b))))
+		}
+	}
+}
+
+var dumphdr = []byte("go1.7 heap dump\n")
+
+func mdump(m *MemStats) {
+	assertWorldStopped()
+
+	// make sure we're done sweeping
+	for _, s := range mheap_.allspans {
+		if s.state.get() == mSpanInUse {
+			s.ensureSwept()
+		}
+	}
+	memclrNoHeapPointers(unsafe.Pointer(&typecache), unsafe.Sizeof(typecache))
+	dwrite(unsafe.Pointer(&dumphdr[0]), uintptr(len(dumphdr)))
+	dumpparams()
+	dumpitabs()
+	dumpobjs()
+	dumpgs()
+	dumpms()
+	dumproots()
+	dumpmemstats(m)
+	dumpmemprof()
+	dumpint(tagEOF)
+	flush()
+}
+
+func writeheapdump_m(fd uintptr, m *MemStats) {
+	assertWorldStopped()
+
+	_g_ := getg()
+	casgstatus(_g_.m.curg, _Grunning, _Gwaiting)
+	_g_.waitreason = waitReasonDumpingHeap
+
+	// Set dump file.
+	dumpfd = fd
+
+	// Call dump routine.
+	mdump(m)
+
+	// Reset dump file.
+	dumpfd = 0
+	if tmpbuf != nil {
+		sysFree(unsafe.Pointer(&tmpbuf[0]), uintptr(len(tmpbuf)), &memstats.other_sys)
+		tmpbuf = nil
+	}
+
+	casgstatus(_g_.m.curg, _Gwaiting, _Grunning)
+}
+
+// dumpint() the kind & offset of each field in an object.
+func dumpfields(bv bitvector) {
+	dumpbv(&bv, 0)
+	dumpint(fieldKindEol)
+}
+
+func makeheapobjbv(p uintptr, size uintptr) bitvector {
+	// Extend the temp buffer if necessary.
+	nptr := size / goarch.PtrSize
+	if uintptr(len(tmpbuf)) < nptr/8+1 {
+		if tmpbuf != nil {
+			sysFree(unsafe.Pointer(&tmpbuf[0]), uintptr(len(tmpbuf)), &memstats.other_sys)
+		}
+		n := nptr/8 + 1
+		p := sysAlloc(n, &memstats.other_sys)
+		if p == nil {
+			throw("heapdump: out of memory")
+		}
+		tmpbuf = (*[1 << 30]byte)(p)[:n]
+	}
+	// Convert heap bitmap to pointer bitmap.
+	for i := uintptr(0); i < nptr/8+1; i++ {
+		tmpbuf[i] = 0
+	}
+	i := uintptr(0)
+	hbits := heapBitsForAddr(p)
+	for ; i < nptr; i++ {
+		if !hbits.morePointers() {
+			break // end of object
+		}
+		if hbits.isPointer() {
+			tmpbuf[i/8] |= 1 << (i % 8)
+		}
+		hbits = hbits.next()
+	}
+	return bitvector{int32(i), &tmpbuf[0]}
+}
diff --git a/contrib/go/_std_1.19/src/runtime/histogram.go b/contrib/go/_std_1.19/src/runtime/histogram.go
new file mode 100644
index 0000000000..eddfbab3bc
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/histogram.go
@@ -0,0 +1,171 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"runtime/internal/atomic"
+	"runtime/internal/sys"
+	"unsafe"
+)
+
+const (
+	// For the time histogram type, we use an HDR histogram.
+	// Values are placed in super-buckets based solely on the most
+	// significant set bit. Thus, super-buckets are power-of-2 sized.
+	// Values are then placed into sub-buckets based on the value of
+	// the next timeHistSubBucketBits most significant bits. Thus,
+	// sub-buckets are linear within a super-bucket.
+	//
+	// Therefore, the number of sub-buckets (timeHistNumSubBuckets)
+	// defines the error. This error may be computed as
+	// 1/timeHistNumSubBuckets*100%. For example, for 16 sub-buckets
+	// per super-bucket the error is approximately 6%.
+	//
+	// The number of super-buckets (timeHistNumSuperBuckets), on the
+	// other hand, defines the range. To reserve room for sub-buckets,
+	// bit timeHistSubBucketBits is the first bit considered for
+	// super-buckets, so super-bucket indices are adjusted accordingly.
+	//
+	// As an example, consider 45 super-buckets with 16 sub-buckets.
+	//
+	//    00110
+	//    ^----
+	//    │  ^
+	//    │  └---- Lowest 4 bits -> sub-bucket 6
+	//    └------- Bit 4 unset -> super-bucket 0
+	//
+	//    10110
+	//    ^----
+	//    │  ^
+	//    │  └---- Next 4 bits -> sub-bucket 6
+	//    └------- Bit 4 set -> super-bucket 1
+	//    100010
+	//    ^----^
+	//    │  ^ └-- Lower bits ignored
+	//    │  └---- Next 4 bits -> sub-bucket 1
+	//    └------- Bit 5 set -> super-bucket 2
+	//
+	// Following this pattern, super-bucket 44 will have the bit 47 set. We don't
+	// have any buckets for higher values, so the highest sub-bucket will
+	// contain values of 2^48-1 nanoseconds or approx. 3 days. This range is
+	// more than enough to handle durations produced by the runtime.
+	timeHistSubBucketBits   = 4
+	timeHistNumSubBuckets   = 1 << timeHistSubBucketBits
+	timeHistNumSuperBuckets = 45
+	timeHistTotalBuckets    = timeHistNumSuperBuckets*timeHistNumSubBuckets + 1
+)
+
+// timeHistogram represents a distribution of durations in
+// nanoseconds.
+//
+// The accuracy and range of the histogram is defined by the
+// timeHistSubBucketBits and timeHistNumSuperBuckets constants.
+//
+// It is an HDR histogram with exponentially-distributed
+// buckets and linearly distributed sub-buckets.
+//
+// Counts in the histogram are updated atomically, so it is safe
+// for concurrent use. It is also safe to read all the values
+// atomically.
+type timeHistogram struct {
+	counts [timeHistNumSuperBuckets * timeHistNumSubBuckets]uint64
+
+	// underflow counts all the times we got a negative duration
+	// sample. Because of how time works on some platforms, it's
+	// possible to measure negative durations. We could ignore them,
+	// but we record them anyway because it's better to have some
+	// signal that it's happening than just missing samples.
+	underflow uint64
+}
+
+// record adds the given duration to the distribution.
+//
+// Disallow preemptions and stack growths because this function
+// may run in sensitive locations.
+//
+//go:nosplit
+func (h *timeHistogram) record(duration int64) {
+	if duration < 0 {
+		atomic.Xadd64(&h.underflow, 1)
+		return
+	}
+	// The index of the exponential bucket is just the index
+	// of the highest set bit adjusted for how many bits we
+	// use for the subbucket. Note that it's timeHistSubBucketsBits-1
+	// because we use the 0th bucket to hold values < timeHistNumSubBuckets.
+	var superBucket, subBucket uint
+	if duration >= timeHistNumSubBuckets {
+		// At this point, we know the duration value will always be
+		// at least timeHistSubBucketsBits long.
+		superBucket = uint(sys.Len64(uint64(duration))) - timeHistSubBucketBits
+		if superBucket*timeHistNumSubBuckets >= uint(len(h.counts)) {
+			// The bucket index we got is larger than what we support, so
+			// include this count in the highest bucket, which extends to
+			// infinity.
+			superBucket = timeHistNumSuperBuckets - 1
+			subBucket = timeHistNumSubBuckets - 1
+		} else {
+			// The linear subbucket index is just the timeHistSubBucketsBits
+			// bits after the top bit. To extract that value, shift down
+			// the duration such that we leave the top bit and the next bits
+			// intact, then extract the index.
+			subBucket = uint((duration >> (superBucket - 1)) % timeHistNumSubBuckets)
+		}
+	} else {
+		subBucket = uint(duration)
+	}
+	atomic.Xadd64(&h.counts[superBucket*timeHistNumSubBuckets+subBucket], 1)
+}
+
+const (
+	fInf    = 0x7FF0000000000000
+	fNegInf = 0xFFF0000000000000
+)
+
+func float64Inf() float64 {
+	inf := uint64(fInf)
+	return *(*float64)(unsafe.Pointer(&inf))
+}
+
+func float64NegInf() float64 {
+	inf := uint64(fNegInf)
+	return *(*float64)(unsafe.Pointer(&inf))
+}
+
+// timeHistogramMetricsBuckets generates a slice of boundaries for
+// the timeHistogram. These boundaries are represented in seconds,
+// not nanoseconds like the timeHistogram represents durations.
+func timeHistogramMetricsBuckets() []float64 {
+	b := make([]float64, timeHistTotalBuckets+1)
+	b[0] = float64NegInf()
+	// Super-bucket 0 has no bits above timeHistSubBucketBits
+	// set, so just iterate over each bucket and assign the
+	// incrementing bucket.
+	for i := 0; i < timeHistNumSubBuckets; i++ {
+		bucketNanos := uint64(i)
+		b[i+1] = float64(bucketNanos) / 1e9
+	}
+	// Generate the rest of the super-buckets. It's easier to reason
+	// about if we cut out the 0'th bucket, so subtract one since
+	// we just handled that bucket.
+	for i := 0; i < timeHistNumSuperBuckets-1; i++ {
+		for j := 0; j < timeHistNumSubBuckets; j++ {
+			// Set the super-bucket bit.
+			bucketNanos := uint64(1) << (i + timeHistSubBucketBits)
+			// Set the sub-bucket bits.
+			bucketNanos |= uint64(j) << i
+			// The index for this bucket is going to be the (i+1)'th super bucket
+			// (note that we're starting from zero, but handled the first super-bucket
+			// earlier, so we need to compensate), and the j'th sub bucket.
+			// Add 1 because we left space for -Inf.
+			bucketIndex := (i+1)*timeHistNumSubBuckets + j + 1
+			// Convert nanoseconds to seconds via a division.
+			// These values will all be exactly representable by a float64.
+			b[bucketIndex] = float64(bucketNanos) / 1e9
+		}
+	}
+	b[len(b)-1] = float64Inf()
+	return b
+}
diff --git a/contrib/go/_std_1.18/src/runtime/iface.go b/contrib/go/_std_1.19/src/runtime/iface.go
index a4d56dd33b..a4d56dd33b 100644
--- a/contrib/go/_std_1.18/src/runtime/iface.go
+++ b/contrib/go/_std_1.19/src/runtime/iface.go
diff --git a/contrib/go/_std_1.19/src/runtime/internal/atomic/atomic_amd64.go b/contrib/go/_std_1.19/src/runtime/internal/atomic/atomic_amd64.go
new file mode 100644
index 0000000000..52a83620c8
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/internal/atomic/atomic_amd64.go
@@ -0,0 +1,117 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package atomic
+
+import "unsafe"
+
+// Export some functions via linkname to assembly in sync/atomic.
+//
+//go:linkname Load
+//go:linkname Loadp
+//go:linkname Load64
+
+//go:nosplit
+//go:noinline
+func Load(ptr *uint32) uint32 {
+	return *ptr
+}
+
+//go:nosplit
+//go:noinline
+func Loadp(ptr unsafe.Pointer) unsafe.Pointer {
+	return *(*unsafe.Pointer)(ptr)
+}
+
+//go:nosplit
+//go:noinline
+func Load64(ptr *uint64) uint64 {
+	return *ptr
+}
+
+//go:nosplit
+//go:noinline
+func LoadAcq(ptr *uint32) uint32 {
+	return *ptr
+}
+
+//go:nosplit
+//go:noinline
+func LoadAcq64(ptr *uint64) uint64 {
+	return *ptr
+}
+
+//go:nosplit
+//go:noinline
+func LoadAcquintptr(ptr *uintptr) uintptr {
+	return *ptr
+}
+
+//go:noescape
+func Xadd(ptr *uint32, delta int32) uint32
+
+//go:noescape
+func Xadd64(ptr *uint64, delta int64) uint64
+
+//go:noescape
+func Xadduintptr(ptr *uintptr, delta uintptr) uintptr
+
+//go:noescape
+func Xchg(ptr *uint32, new uint32) uint32
+
+//go:noescape
+func Xchg64(ptr *uint64, new uint64) uint64
+
+//go:noescape
+func Xchguintptr(ptr *uintptr, new uintptr) uintptr
+
+//go:nosplit
+//go:noinline
+func Load8(ptr *uint8) uint8 {
+	return *ptr
+}
+
+//go:noescape
+func And8(ptr *uint8, val uint8)
+
+//go:noescape
+func Or8(ptr *uint8, val uint8)
+
+//go:noescape
+func And(ptr *uint32, val uint32)
+
+//go:noescape
+func Or(ptr *uint32, val uint32)
+
+// NOTE: Do not add atomicxor8 (XOR is not idempotent).
+
+//go:noescape
+func Cas64(ptr *uint64, old, new uint64) bool
+
+//go:noescape
+func CasRel(ptr *uint32, old, new uint32) bool
+
+//go:noescape
+func Store(ptr *uint32, val uint32)
+
+//go:noescape
+func Store8(ptr *uint8, val uint8)
+
+//go:noescape
+func Store64(ptr *uint64, val uint64)
+
+//go:noescape
+func StoreRel(ptr *uint32, val uint32)
+
+//go:noescape
+func StoreRel64(ptr *uint64, val uint64)
+
+//go:noescape
+func StoreReluintptr(ptr *uintptr, val uintptr)
+
+// StorepNoWB performs *ptr = val atomically and without a write
+// barrier.
+//
+// NO go:noescape annotation; see atomic_pointer.go.
+func StorepNoWB(ptr unsafe.Pointer, val unsafe.Pointer)
diff --git a/contrib/go/_std_1.18/src/runtime/internal/atomic/atomic_amd64.s b/contrib/go/_std_1.19/src/runtime/internal/atomic/atomic_amd64.s
index d21514b36b..d21514b36b 100644
--- a/contrib/go/_std_1.18/src/runtime/internal/atomic/atomic_amd64.s
+++ b/contrib/go/_std_1.19/src/runtime/internal/atomic/atomic_amd64.s
diff --git a/contrib/go/_std_1.18/src/runtime/internal/atomic/doc.go b/contrib/go/_std_1.19/src/runtime/internal/atomic/doc.go
index 08e6b6ce0b..08e6b6ce0b 100644
--- a/contrib/go/_std_1.18/src/runtime/internal/atomic/doc.go
+++ b/contrib/go/_std_1.19/src/runtime/internal/atomic/doc.go
diff --git a/contrib/go/_std_1.18/src/runtime/internal/atomic/stubs.go b/contrib/go/_std_1.19/src/runtime/internal/atomic/stubs.go
index 7df8d9c863..7df8d9c863 100644
--- a/contrib/go/_std_1.18/src/runtime/internal/atomic/stubs.go
+++ b/contrib/go/_std_1.19/src/runtime/internal/atomic/stubs.go
diff --git a/contrib/go/_std_1.19/src/runtime/internal/atomic/types.go b/contrib/go/_std_1.19/src/runtime/internal/atomic/types.go
new file mode 100644
index 0000000000..d346a76b67
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/internal/atomic/types.go
@@ -0,0 +1,431 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package atomic
+
+import "unsafe"
+
+// Int32 is an atomically accessed int32 value.
+//
+// An Int32 must not be copied.
+type Int32 struct {
+	noCopy noCopy
+	value  int32
+}
+
+// Load accesses and returns the value atomically.
+func (i *Int32) Load() int32 {
+	return Loadint32(&i.value)
+}
+
+// Store updates the value atomically.
+func (i *Int32) Store(value int32) {
+	Storeint32(&i.value, value)
+}
+
+// CompareAndSwap atomically compares i's value with old,
+// and if they're equal, swaps i's value with new.
+//
+// Returns true if the operation succeeded.
+func (i *Int32) CompareAndSwap(old, new int32) bool {
+	return Casint32(&i.value, old, new)
+}
+
+// Swap replaces i's value with new, returning
+// i's value before the replacement.
+func (i *Int32) Swap(new int32) int32 {
+	return Xchgint32(&i.value, new)
+}
+
+// Add adds delta to i atomically, returning
+// the new updated value.
+//
+// This operation wraps around in the usual
+// two's-complement way.
+func (i *Int32) Add(delta int32) int32 {
+	return Xaddint32(&i.value, delta)
+}
+
+// Int64 is an atomically accessed int64 value.
+//
+// 8-byte aligned on all platforms, unlike a regular int64.
+//
+// An Int64 must not be copied.
+type Int64 struct {
+	noCopy noCopy
+	_      align64
+	value  int64
+}
+
+// Load accesses and returns the value atomically.
+func (i *Int64) Load() int64 {
+	return Loadint64(&i.value)
+}
+
+// Store updates the value atomically.
+func (i *Int64) Store(value int64) {
+	Storeint64(&i.value, value)
+}
+
+// CompareAndSwap atomically compares i's value with old,
+// and if they're equal, swaps i's value with new.
+//
+// Returns true if the operation succeeded.
+func (i *Int64) CompareAndSwap(old, new int64) bool {
+	return Casint64(&i.value, old, new)
+}
+
+// Swap replaces i's value with new, returning
+// i's value before the replacement.
+func (i *Int64) Swap(new int64) int64 {
+	return Xchgint64(&i.value, new)
+}
+
+// Add adds delta to i atomically, returning
+// the new updated value.
+//
+// This operation wraps around in the usual
+// two's-complement way.
+func (i *Int64) Add(delta int64) int64 {
+	return Xaddint64(&i.value, delta)
+}
+
+// Uint8 is an atomically accessed uint8 value.
+//
+// A Uint8 must not be copied.
+type Uint8 struct {
+	noCopy noCopy
+	value  uint8
+}
+
+// Load accesses and returns the value atomically.
+func (u *Uint8) Load() uint8 {
+	return Load8(&u.value)
+}
+
+// Store updates the value atomically.
+func (u *Uint8) Store(value uint8) {
+	Store8(&u.value, value)
+}
+
+// And takes value and performs a bit-wise
+// "and" operation with the value of u, storing
+// the result into u.
+//
+// The full process is performed atomically.
+func (u *Uint8) And(value uint8) {
+	And8(&u.value, value)
+}
+
+// Or takes value and performs a bit-wise
+// "or" operation with the value of u, storing
+// the result into u.
+//
+// The full process is performed atomically.
+func (u *Uint8) Or(value uint8) {
+	Or8(&u.value, value)
+}
+
+// Bool is an atomically accessed bool value.
+//
+// A Bool must not be copied.
+type Bool struct {
+	// Inherits noCopy from Uint8.
+	u Uint8
+}
+
+// Load accesses and returns the value atomically.
+func (b *Bool) Load() bool {
+	return b.u.Load() != 0
+}
+
+// Store updates the value atomically.
+func (b *Bool) Store(value bool) {
+	s := uint8(0)
+	if value {
+		s = 1
+	}
+	b.u.Store(s)
+}
+
+// Uint32 is an atomically accessed uint32 value.
+//
+// A Uint32 must not be copied.
+type Uint32 struct {
+	noCopy noCopy
+	value  uint32
+}
+
+// Load accesses and returns the value atomically.
+func (u *Uint32) Load() uint32 {
+	return Load(&u.value)
+}
+
+// LoadAcquire is a partially unsynchronized version
+// of Load that relaxes ordering constraints. Other threads
+// may observe operations that precede this operation to
+// occur after it, but no operation that occurs after it
+// on this thread can be observed to occur before it.
+//
+// WARNING: Use sparingly and with great care.
+func (u *Uint32) LoadAcquire() uint32 {
+	return LoadAcq(&u.value)
+}
+
+// Store updates the value atomically.
+func (u *Uint32) Store(value uint32) {
+	Store(&u.value, value)
+}
+
+// StoreRelease is a partially unsynchronized version
+// of Store that relaxes ordering constraints. Other threads
+// may observe operations that occur after this operation to
+// precede it, but no operation that precedes it
+// on this thread can be observed to occur after it.
+//
+// WARNING: Use sparingly and with great care.
+func (u *Uint32) StoreRelease(value uint32) {
+	StoreRel(&u.value, value)
+}
+
+// CompareAndSwap atomically compares u's value with old,
+// and if they're equal, swaps u's value with new.
+//
+// Returns true if the operation succeeded.
+func (u *Uint32) CompareAndSwap(old, new uint32) bool {
+	return Cas(&u.value, old, new)
+}
+
+// CompareAndSwapRelease is a partially unsynchronized version
+// of Cas that relaxes ordering constraints. Other threads
+// may observe operations that occur after this operation to
+// precede it, but no operation that precedes it
+// on this thread can be observed to occur after it.
+//
+// Returns true if the operation succeeded.
+//
+// WARNING: Use sparingly and with great care.
+func (u *Uint32) CompareAndSwapRelease(old, new uint32) bool {
+	return CasRel(&u.value, old, new)
+}
+
+// Swap replaces u's value with new, returning
+// u's value before the replacement.
+func (u *Uint32) Swap(value uint32) uint32 {
+	return Xchg(&u.value, value)
+}
+
+// And takes value and performs a bit-wise
+// "and" operation with the value of u, storing
+// the result into u.
+//
+// The full process is performed atomically.
+func (u *Uint32) And(value uint32) {
+	And(&u.value, value)
+}
+
+// Or takes value and performs a bit-wise
+// "or" operation with the value of u, storing
+// the result into u.
+//
+// The full process is performed atomically.
+func (u *Uint32) Or(value uint32) {
+	Or(&u.value, value)
+}
+
+// Add adds delta to u atomically, returning
+// the new updated value.
+//
+// This operation wraps around in the usual
+// two's-complement way.
+func (u *Uint32) Add(delta int32) uint32 {
+	return Xadd(&u.value, delta)
+}
+
+// Uint64 is an atomically accessed uint64 value.
+//
+// 8-byte aligned on all platforms, unlike a regular uint64.
+//
+// A Uint64 must not be copied.
+type Uint64 struct {
+	noCopy noCopy
+	_      align64
+	value  uint64
+}
+
+// Load accesses and returns the value atomically.
+func (u *Uint64) Load() uint64 {
+	return Load64(&u.value)
+}
+
+// Store updates the value atomically.
+func (u *Uint64) Store(value uint64) {
+	Store64(&u.value, value)
+}
+
+// CompareAndSwap atomically compares u's value with old,
+// and if they're equal, swaps u's value with new.
+//
+// Returns true if the operation succeeded.
+func (u *Uint64) CompareAndSwap(old, new uint64) bool {
+	return Cas64(&u.value, old, new)
+}
+
+// Swap replaces u's value with new, returning
+// u's value before the replacement.
+func (u *Uint64) Swap(value uint64) uint64 {
+	return Xchg64(&u.value, value)
+}
+
+// Add adds delta to u atomically, returning
+// the new updated value.
+//
+// This operation wraps around in the usual
+// two's-complement way.
+func (u *Uint64) Add(delta int64) uint64 {
+	return Xadd64(&u.value, delta)
+}
+
+// Uintptr is an atomically accessed uintptr value.
+//
+// A Uintptr must not be copied.
+type Uintptr struct {
+	noCopy noCopy
+	value  uintptr
+}
+
+// Load accesses and returns the value atomically.
+func (u *Uintptr) Load() uintptr {
+	return Loaduintptr(&u.value)
+}
+
+// LoadAcquire is a partially unsynchronized version
+// of Load that relaxes ordering constraints. Other threads
+// may observe operations that precede this operation to
+// occur after it, but no operation that occurs after it
+// on this thread can be observed to occur before it.
+//
+// WARNING: Use sparingly and with great care.
+func (u *Uintptr) LoadAcquire() uintptr {
+	return LoadAcquintptr(&u.value)
+}
+
+// Store updates the value atomically.
+func (u *Uintptr) Store(value uintptr) {
+	Storeuintptr(&u.value, value)
+}
+
+// StoreRelease is a partially unsynchronized version
+// of Store that relaxes ordering constraints. Other threads
+// may observe operations that occur after this operation to
+// precede it, but no operation that precedes it
+// on this thread can be observed to occur after it.
+//
+// WARNING: Use sparingly and with great care.
+func (u *Uintptr) StoreRelease(value uintptr) {
+	StoreReluintptr(&u.value, value)
+}
+
+// CompareAndSwap atomically compares u's value with old,
+// and if they're equal, swaps u's value with new.
+//
+// Returns true if the operation succeeded.
+func (u *Uintptr) CompareAndSwap(old, new uintptr) bool {
+	return Casuintptr(&u.value, old, new)
+}
+
+// Swap replaces u's value with new, returning
+// u's value before the replacement.
+func (u *Uintptr) Swap(value uintptr) uintptr {
+	return Xchguintptr(&u.value, value)
+}
+
+// Add adds delta to u atomically, returning
+// the new updated value.
+//
+// This operation wraps around in the usual
+// two's-complement way.
+func (u *Uintptr) Add(delta uintptr) uintptr {
+	return Xadduintptr(&u.value, delta)
+}
+
+// Float64 is an atomically accessed float64 value.
+//
+// 8-byte aligned on all platforms, unlike a regular float64.
+//
+// A Float64 must not be copied.
+type Float64 struct {
+	// Inherits noCopy and align64 from Uint64.
+	u Uint64
+}
+
+// Load accesses and returns the value atomically.
+func (f *Float64) Load() float64 {
+	r := f.u.Load()
+	return *(*float64)(unsafe.Pointer(&r))
+}
+
+// Store updates the value atomically.
+func (f *Float64) Store(value float64) {
+	f.u.Store(*(*uint64)(unsafe.Pointer(&value)))
+}
+
+// UnsafePointer is an atomically accessed unsafe.Pointer value.
+//
+// Note that because of the atomicity guarantees, stores to values
+// of this type never trigger a write barrier, and the relevant
+// methods are suffixed with "NoWB" to indicate that explicitly.
+// As a result, this type should be used carefully, and sparingly,
+// mostly with values that do not live in the Go heap anyway.
+//
+// An UnsafePointer must not be copied.
+type UnsafePointer struct {
+	noCopy noCopy
+	value  unsafe.Pointer
+}
+
+// Load accesses and returns the value atomically.
+func (u *UnsafePointer) Load() unsafe.Pointer {
+	return Loadp(unsafe.Pointer(&u.value))
+}
+
+// StoreNoWB updates the value atomically.
+//
+// WARNING: As the name implies this operation does *not*
+// perform a write barrier on value, and so this operation may
+// hide pointers from the GC. Use with care and sparingly.
+// It is safe to use with values not found in the Go heap.
+func (u *UnsafePointer) StoreNoWB(value unsafe.Pointer) {
+	StorepNoWB(unsafe.Pointer(&u.value), value)
+}
+
+// CompareAndSwapNoWB atomically (with respect to other methods)
+// compares u's value with old, and if they're equal,
+// swaps u's value with new.
+//
+// Returns true if the operation succeeded.
+//
+// WARNING: As the name implies this operation does *not*
+// perform a write barrier on value, and so this operation may
+// hide pointers from the GC. Use with care and sparingly.
+// It is safe to use with values not found in the Go heap.
+func (u *UnsafePointer) CompareAndSwapNoWB(old, new unsafe.Pointer) bool {
+	return Casp1(&u.value, old, new)
+}
+
+// noCopy may be embedded into structs which must not be copied
+// after the first use.
+//
+// See https://golang.org/issues/8005#issuecomment-190753527
+// for details.
+type noCopy struct{}
+
+// Lock is a no-op used by -copylocks checker from `go vet`.
+func (*noCopy) Lock()   {}
+func (*noCopy) Unlock() {}
+
+// align64 may be added to structs that must be 64-bit aligned.
+// This struct is recognized by a special case in the compiler
+// and will not work if copied to any other package.
+type align64 struct{}
diff --git a/contrib/go/_std_1.18/src/runtime/internal/atomic/types_64bit.go b/contrib/go/_std_1.19/src/runtime/internal/atomic/types_64bit.go
index 43c1ba2709..43c1ba2709 100644
--- a/contrib/go/_std_1.18/src/runtime/internal/atomic/types_64bit.go
+++ b/contrib/go/_std_1.19/src/runtime/internal/atomic/types_64bit.go
diff --git a/contrib/go/_std_1.18/src/runtime/internal/atomic/unaligned.go b/contrib/go/_std_1.19/src/runtime/internal/atomic/unaligned.go
index a859de4144..a859de4144 100644
--- a/contrib/go/_std_1.18/src/runtime/internal/atomic/unaligned.go
+++ b/contrib/go/_std_1.19/src/runtime/internal/atomic/unaligned.go
diff --git a/contrib/go/_std_1.18/src/runtime/internal/math/math.go b/contrib/go/_std_1.19/src/runtime/internal/math/math.go
index c3fac366be..c3fac366be 100644
--- a/contrib/go/_std_1.18/src/runtime/internal/math/math.go
+++ b/contrib/go/_std_1.19/src/runtime/internal/math/math.go
diff --git a/contrib/go/_std_1.18/src/runtime/internal/sys/consts.go b/contrib/go/_std_1.19/src/runtime/internal/sys/consts.go
index fffcf81d1f..fffcf81d1f 100644
--- a/contrib/go/_std_1.18/src/runtime/internal/sys/consts.go
+++ b/contrib/go/_std_1.19/src/runtime/internal/sys/consts.go
diff --git a/contrib/go/_std_1.18/src/runtime/internal/sys/intrinsics.go b/contrib/go/_std_1.19/src/runtime/internal/sys/intrinsics.go
index 5af49011e9..5af49011e9 100644
--- a/contrib/go/_std_1.18/src/runtime/internal/sys/intrinsics.go
+++ b/contrib/go/_std_1.19/src/runtime/internal/sys/intrinsics.go
diff --git a/contrib/go/_std_1.18/src/runtime/internal/sys/intrinsics_common.go b/contrib/go/_std_1.19/src/runtime/internal/sys/intrinsics_common.go
index 48d9759ca9..48d9759ca9 100644
--- a/contrib/go/_std_1.18/src/runtime/internal/sys/intrinsics_common.go
+++ b/contrib/go/_std_1.19/src/runtime/internal/sys/intrinsics_common.go
diff --git a/contrib/go/_std_1.18/src/runtime/internal/sys/sys.go b/contrib/go/_std_1.19/src/runtime/internal/sys/sys.go
index 694101d36f..694101d36f 100644
--- a/contrib/go/_std_1.18/src/runtime/internal/sys/sys.go
+++ b/contrib/go/_std_1.19/src/runtime/internal/sys/sys.go
diff --git a/contrib/go/_std_1.18/src/runtime/internal/sys/zversion.go b/contrib/go/_std_1.19/src/runtime/internal/sys/zversion.go
index b058a3db70..b058a3db70 100644
--- a/contrib/go/_std_1.18/src/runtime/internal/sys/zversion.go
+++ b/contrib/go/_std_1.19/src/runtime/internal/sys/zversion.go
diff --git a/contrib/go/_std_1.19/src/runtime/internal/syscall/asm_linux_amd64.s b/contrib/go/_std_1.19/src/runtime/internal/syscall/asm_linux_amd64.s
new file mode 100644
index 0000000000..3740ef1beb
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/internal/syscall/asm_linux_amd64.s
@@ -0,0 +1,47 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// func Syscall6(num, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, errno uintptr)
+//
+// We need to convert to the syscall ABI.
+//
+// arg | ABIInternal | Syscall
+// ---------------------------
+// num | AX          | AX
+// a1  | BX          | DI
+// a2  | CX          | SI
+// a3  | DI          | DX
+// a4  | SI          | R10
+// a5  | R8          | R8
+// a6  | R9          | R9
+//
+// r1  | AX          | AX
+// r2  | BX          | DX
+// err | CX          | part of AX
+//
+// Note that this differs from "standard" ABI convention, which would pass 4th
+// arg in CX, not R10.
+TEXT ·Syscall6<ABIInternal>(SB),NOSPLIT,$0
+	// a6 already in R9.
+	// a5 already in R8.
+	MOVQ	SI, R10 // a4
+	MOVQ	DI, DX  // a3
+	MOVQ	CX, SI  // a2
+	MOVQ	BX, DI  // a1
+	// num already in AX.
+	SYSCALL
+	CMPQ	AX, $0xfffffffffffff001
+	JLS	ok
+	NEGQ	AX
+	MOVQ	AX, CX  // errno
+	MOVQ	$-1, AX // r1
+	MOVQ	$0, BX  // r2
+	RET
+ok:
+	// r1 already in AX.
+	MOVQ	DX, BX // r2
+	MOVQ	$0, CX // errno
+	RET
diff --git a/contrib/go/_std_1.19/src/runtime/internal/syscall/syscall_linux.go b/contrib/go/_std_1.19/src/runtime/internal/syscall/syscall_linux.go
new file mode 100644
index 0000000000..7f268e8fba
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/internal/syscall/syscall_linux.go
@@ -0,0 +1,39 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package syscall provides the syscall primitives required for the runtime.
+package syscall
+
+import (
+	_ "unsafe" // for go:linkname
+)
+
+// TODO(https://go.dev/issue/51087): This package is incomplete and currently
+// only contains very minimal support for Linux.
+
+// Syscall6 calls system call number 'num' with arguments a1-6.
+func Syscall6(num, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, errno uintptr)
+
+// syscall_RawSyscall6 is a push linkname to export Syscall6 as
+// syscall.RawSyscall6.
+//
+// //go:uintptrkeepalive because the uintptr argument may be converted pointers
+// that need to be kept alive in the caller (this is implied for Syscall6 since
+// it has no body).
+//
+// //go:nosplit because stack copying does not account for uintptrkeepalive, so
+// the stack must not grow. Stack copying cannot blindly assume that all
+// uintptr arguments are pointers, because some values may look like pointers,
+// but not really be pointers, and adjusting their value would break the call.
+//
+// This is a separate wrapper because we can't export one function as two
+// names. The assembly implementations name themselves Syscall6 would not be
+// affected by a linkname.
+//
+//go:uintptrkeepalive
+//go:nosplit
+//go:linkname syscall_RawSyscall6 syscall.RawSyscall6
+func syscall_RawSyscall6(num, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, errno uintptr) {
+	return Syscall6(num, a1, a2, a3, a4, a5, a6)
+}
diff --git a/contrib/go/_std_1.18/src/runtime/lfstack.go b/contrib/go/_std_1.19/src/runtime/lfstack.go
index 406561a275..406561a275 100644
--- a/contrib/go/_std_1.18/src/runtime/lfstack.go
+++ b/contrib/go/_std_1.19/src/runtime/lfstack.go
diff --git a/contrib/go/_std_1.19/src/runtime/lfstack_64bit.go b/contrib/go/_std_1.19/src/runtime/lfstack_64bit.go
new file mode 100644
index 0000000000..154130cf63
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/lfstack_64bit.go
@@ -0,0 +1,58 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build amd64 || arm64 || loong64 || mips64 || mips64le || ppc64 || ppc64le || riscv64 || s390x || wasm
+
+package runtime
+
+import "unsafe"
+
+const (
+	// addrBits is the number of bits needed to represent a virtual address.
+	//
+	// See heapAddrBits for a table of address space sizes on
+	// various architectures. 48 bits is enough for all
+	// architectures except s390x.
+	//
+	// On AMD64, virtual addresses are 48-bit (or 57-bit) numbers sign extended to 64.
+	// We shift the address left 16 to eliminate the sign extended part and make
+	// room in the bottom for the count.
+	//
+	// On s390x, virtual addresses are 64-bit. There's not much we
+	// can do about this, so we just hope that the kernel doesn't
+	// get to really high addresses and panic if it does.
+	addrBits = 48
+
+	// In addition to the 16 bits taken from the top, we can take 3 from the
+	// bottom, because node must be pointer-aligned, giving a total of 19 bits
+	// of count.
+	cntBits = 64 - addrBits + 3
+
+	// On AIX, 64-bit addresses are split into 36-bit segment number and 28-bit
+	// offset in segment.  Segment numbers in the range 0x0A0000000-0x0AFFFFFFF(LSA)
+	// are available for mmap.
+	// We assume all lfnode addresses are from memory allocated with mmap.
+	// We use one bit to distinguish between the two ranges.
+	aixAddrBits = 57
+	aixCntBits  = 64 - aixAddrBits + 3
+)
+
+func lfstackPack(node *lfnode, cnt uintptr) uint64 {
+	if GOARCH == "ppc64" && GOOS == "aix" {
+		return uint64(uintptr(unsafe.Pointer(node)))<<(64-aixAddrBits) | uint64(cnt&(1<<aixCntBits-1))
+	}
+	return uint64(uintptr(unsafe.Pointer(node)))<<(64-addrBits) | uint64(cnt&(1<<cntBits-1))
+}
+
+func lfstackUnpack(val uint64) *lfnode {
+	if GOARCH == "amd64" {
+		// amd64 systems can place the stack above the VA hole, so we need to sign extend
+		// val before unpacking.
+		return (*lfnode)(unsafe.Pointer(uintptr(int64(val) >> cntBits << 3)))
+	}
+	if GOARCH == "ppc64" && GOOS == "aix" {
+		return (*lfnode)(unsafe.Pointer(uintptr((val >> aixCntBits << 3) | 0xa<<56)))
+	}
+	return (*lfnode)(unsafe.Pointer(uintptr(val >> cntBits << 3)))
+}
diff --git a/contrib/go/_std_1.19/src/runtime/lock_futex.go b/contrib/go/_std_1.19/src/runtime/lock_futex.go
new file mode 100644
index 0000000000..1578984ce2
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/lock_futex.go
@@ -0,0 +1,246 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build dragonfly || freebsd || linux
+
+package runtime
+
+import (
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+// This implementation depends on OS-specific implementations of
+//
+//	futexsleep(addr *uint32, val uint32, ns int64)
+//		Atomically,
+//			if *addr == val { sleep }
+//		Might be woken up spuriously; that's allowed.
+//		Don't sleep longer than ns; ns < 0 means forever.
+//
+//	futexwakeup(addr *uint32, cnt uint32)
+//		If any procs are sleeping on addr, wake up at most cnt.
+
+const (
+	mutex_unlocked = 0
+	mutex_locked   = 1
+	mutex_sleeping = 2
+
+	active_spin     = 4
+	active_spin_cnt = 30
+	passive_spin    = 1
+)
+
+// Possible lock states are mutex_unlocked, mutex_locked and mutex_sleeping.
+// mutex_sleeping means that there is presumably at least one sleeping thread.
+// Note that there can be spinning threads during all states - they do not
+// affect mutex's state.
+
+// We use the uintptr mutex.key and note.key as a uint32.
+//
+//go:nosplit
+func key32(p *uintptr) *uint32 {
+	return (*uint32)(unsafe.Pointer(p))
+}
+
+func lock(l *mutex) {
+	lockWithRank(l, getLockRank(l))
+}
+
+func lock2(l *mutex) {
+	gp := getg()
+
+	if gp.m.locks < 0 {
+		throw("runtime·lock: lock count")
+	}
+	gp.m.locks++
+
+	// Speculative grab for lock.
+	v := atomic.Xchg(key32(&l.key), mutex_locked)
+	if v == mutex_unlocked {
+		return
+	}
+
+	// wait is either MUTEX_LOCKED or MUTEX_SLEEPING
+	// depending on whether there is a thread sleeping
+	// on this mutex. If we ever change l->key from
+	// MUTEX_SLEEPING to some other value, we must be
+	// careful to change it back to MUTEX_SLEEPING before
+	// returning, to ensure that the sleeping thread gets
+	// its wakeup call.
+	wait := v
+
+	// On uniprocessors, no point spinning.
+	// On multiprocessors, spin for ACTIVE_SPIN attempts.
+	spin := 0
+	if ncpu > 1 {
+		spin = active_spin
+	}
+	for {
+		// Try for lock, spinning.
+		for i := 0; i < spin; i++ {
+			for l.key == mutex_unlocked {
+				if atomic.Cas(key32(&l.key), mutex_unlocked, wait) {
+					return
+				}
+			}
+			procyield(active_spin_cnt)
+		}
+
+		// Try for lock, rescheduling.
+		for i := 0; i < passive_spin; i++ {
+			for l.key == mutex_unlocked {
+				if atomic.Cas(key32(&l.key), mutex_unlocked, wait) {
+					return
+				}
+			}
+			osyield()
+		}
+
+		// Sleep.
+		v = atomic.Xchg(key32(&l.key), mutex_sleeping)
+		if v == mutex_unlocked {
+			return
+		}
+		wait = mutex_sleeping
+		futexsleep(key32(&l.key), mutex_sleeping, -1)
+	}
+}
+
+func unlock(l *mutex) {
+	unlockWithRank(l)
+}
+
+func unlock2(l *mutex) {
+	v := atomic.Xchg(key32(&l.key), mutex_unlocked)
+	if v == mutex_unlocked {
+		throw("unlock of unlocked lock")
+	}
+	if v == mutex_sleeping {
+		futexwakeup(key32(&l.key), 1)
+	}
+
+	gp := getg()
+	gp.m.locks--
+	if gp.m.locks < 0 {
+		throw("runtime·unlock: lock count")
+	}
+	if gp.m.locks == 0 && gp.preempt { // restore the preemption request in case we've cleared it in newstack
+		gp.stackguard0 = stackPreempt
+	}
+}
+
+// One-time notifications.
+func noteclear(n *note) {
+	n.key = 0
+}
+
+func notewakeup(n *note) {
+	old := atomic.Xchg(key32(&n.key), 1)
+	if old != 0 {
+		print("notewakeup - double wakeup (", old, ")\n")
+		throw("notewakeup - double wakeup")
+	}
+	futexwakeup(key32(&n.key), 1)
+}
+
+func notesleep(n *note) {
+	gp := getg()
+	if gp != gp.m.g0 {
+		throw("notesleep not on g0")
+	}
+	ns := int64(-1)
+	if *cgo_yield != nil {
+		// Sleep for an arbitrary-but-moderate interval to poll libc interceptors.
+		ns = 10e6
+	}
+	for atomic.Load(key32(&n.key)) == 0 {
+		gp.m.blocked = true
+		futexsleep(key32(&n.key), 0, ns)
+		if *cgo_yield != nil {
+			asmcgocall(*cgo_yield, nil)
+		}
+		gp.m.blocked = false
+	}
+}
+
+// May run with m.p==nil if called from notetsleep, so write barriers
+// are not allowed.
+//
+//go:nosplit
+//go:nowritebarrier
+func notetsleep_internal(n *note, ns int64) bool {
+	gp := getg()
+
+	if ns < 0 {
+		if *cgo_yield != nil {
+			// Sleep for an arbitrary-but-moderate interval to poll libc interceptors.
+			ns = 10e6
+		}
+		for atomic.Load(key32(&n.key)) == 0 {
+			gp.m.blocked = true
+			futexsleep(key32(&n.key), 0, ns)
+			if *cgo_yield != nil {
+				asmcgocall(*cgo_yield, nil)
+			}
+			gp.m.blocked = false
+		}
+		return true
+	}
+
+	if atomic.Load(key32(&n.key)) != 0 {
+		return true
+	}
+
+	deadline := nanotime() + ns
+	for {
+		if *cgo_yield != nil && ns > 10e6 {
+			ns = 10e6
+		}
+		gp.m.blocked = true
+		futexsleep(key32(&n.key), 0, ns)
+		if *cgo_yield != nil {
+			asmcgocall(*cgo_yield, nil)
+		}
+		gp.m.blocked = false
+		if atomic.Load(key32(&n.key)) != 0 {
+			break
+		}
+		now := nanotime()
+		if now >= deadline {
+			break
+		}
+		ns = deadline - now
+	}
+	return atomic.Load(key32(&n.key)) != 0
+}
+
+func notetsleep(n *note, ns int64) bool {
+	gp := getg()
+	if gp != gp.m.g0 && gp.m.preemptoff != "" {
+		throw("notetsleep not on g0")
+	}
+
+	return notetsleep_internal(n, ns)
+}
+
+// same as runtime·notetsleep, but called on user g (not g0)
+// calls only nosplit functions between entersyscallblock/exitsyscall
+func notetsleepg(n *note, ns int64) bool {
+	gp := getg()
+	if gp == gp.m.g0 {
+		throw("notetsleepg on g0")
+	}
+
+	entersyscallblock()
+	ok := notetsleep_internal(n, ns)
+	exitsyscall()
+	return ok
+}
+
+func beforeIdle(int64, int64) (*g, bool) {
+	return nil, false
+}
+
+func checkTimeouts() {}
diff --git a/contrib/go/_std_1.19/src/runtime/lock_sema.go b/contrib/go/_std_1.19/src/runtime/lock_sema.go
new file mode 100644
index 0000000000..c5e8cfe24a
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/lock_sema.go
@@ -0,0 +1,304 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build aix || darwin || netbsd || openbsd || plan9 || solaris || windows
+
+package runtime
+
+import (
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+// This implementation depends on OS-specific implementations of
+//
+//	func semacreate(mp *m)
+//		Create a semaphore for mp, if it does not already have one.
+//
+//	func semasleep(ns int64) int32
+//		If ns < 0, acquire m's semaphore and return 0.
+//		If ns >= 0, try to acquire m's semaphore for at most ns nanoseconds.
+//		Return 0 if the semaphore was acquired, -1 if interrupted or timed out.
+//
+//	func semawakeup(mp *m)
+//		Wake up mp, which is or will soon be sleeping on its semaphore.
+const (
+	locked uintptr = 1
+
+	active_spin     = 4
+	active_spin_cnt = 30
+	passive_spin    = 1
+)
+
+func lock(l *mutex) {
+	lockWithRank(l, getLockRank(l))
+}
+
+func lock2(l *mutex) {
+	gp := getg()
+	if gp.m.locks < 0 {
+		throw("runtime·lock: lock count")
+	}
+	gp.m.locks++
+
+	// Speculative grab for lock.
+	if atomic.Casuintptr(&l.key, 0, locked) {
+		return
+	}
+	semacreate(gp.m)
+
+	// On uniprocessor's, no point spinning.
+	// On multiprocessors, spin for ACTIVE_SPIN attempts.
+	spin := 0
+	if ncpu > 1 {
+		spin = active_spin
+	}
+Loop:
+	for i := 0; ; i++ {
+		v := atomic.Loaduintptr(&l.key)
+		if v&locked == 0 {
+			// Unlocked. Try to lock.
+			if atomic.Casuintptr(&l.key, v, v|locked) {
+				return
+			}
+			i = 0
+		}
+		if i < spin {
+			procyield(active_spin_cnt)
+		} else if i < spin+passive_spin {
+			osyield()
+		} else {
+			// Someone else has it.
+			// l->waitm points to a linked list of M's waiting
+			// for this lock, chained through m->nextwaitm.
+			// Queue this M.
+			for {
+				gp.m.nextwaitm = muintptr(v &^ locked)
+				if atomic.Casuintptr(&l.key, v, uintptr(unsafe.Pointer(gp.m))|locked) {
+					break
+				}
+				v = atomic.Loaduintptr(&l.key)
+				if v&locked == 0 {
+					continue Loop
+				}
+			}
+			if v&locked != 0 {
+				// Queued. Wait.
+				semasleep(-1)
+				i = 0
+			}
+		}
+	}
+}
+
+func unlock(l *mutex) {
+	unlockWithRank(l)
+}
+
+// We might not be holding a p in this code.
+//
+//go:nowritebarrier
+func unlock2(l *mutex) {
+	gp := getg()
+	var mp *m
+	for {
+		v := atomic.Loaduintptr(&l.key)
+		if v == locked {
+			if atomic.Casuintptr(&l.key, locked, 0) {
+				break
+			}
+		} else {
+			// Other M's are waiting for the lock.
+			// Dequeue an M.
+			mp = muintptr(v &^ locked).ptr()
+			if atomic.Casuintptr(&l.key, v, uintptr(mp.nextwaitm)) {
+				// Dequeued an M.  Wake it.
+				semawakeup(mp)
+				break
+			}
+		}
+	}
+	gp.m.locks--
+	if gp.m.locks < 0 {
+		throw("runtime·unlock: lock count")
+	}
+	if gp.m.locks == 0 && gp.preempt { // restore the preemption request in case we've cleared it in newstack
+		gp.stackguard0 = stackPreempt
+	}
+}
+
+// One-time notifications.
+func noteclear(n *note) {
+	if GOOS == "aix" {
+		// On AIX, semaphores might not synchronize the memory in some
+		// rare cases. See issue #30189.
+		atomic.Storeuintptr(&n.key, 0)
+	} else {
+		n.key = 0
+	}
+}
+
+func notewakeup(n *note) {
+	var v uintptr
+	for {
+		v = atomic.Loaduintptr(&n.key)
+		if atomic.Casuintptr(&n.key, v, locked) {
+			break
+		}
+	}
+
+	// Successfully set waitm to locked.
+	// What was it before?
+	switch {
+	case v == 0:
+		// Nothing was waiting. Done.
+	case v == locked:
+		// Two notewakeups! Not allowed.
+		throw("notewakeup - double wakeup")
+	default:
+		// Must be the waiting m. Wake it up.
+		semawakeup((*m)(unsafe.Pointer(v)))
+	}
+}
+
+func notesleep(n *note) {
+	gp := getg()
+	if gp != gp.m.g0 {
+		throw("notesleep not on g0")
+	}
+	semacreate(gp.m)
+	if !atomic.Casuintptr(&n.key, 0, uintptr(unsafe.Pointer(gp.m))) {
+		// Must be locked (got wakeup).
+		if n.key != locked {
+			throw("notesleep - waitm out of sync")
+		}
+		return
+	}
+	// Queued. Sleep.
+	gp.m.blocked = true
+	if *cgo_yield == nil {
+		semasleep(-1)
+	} else {
+		// Sleep for an arbitrary-but-moderate interval to poll libc interceptors.
+		const ns = 10e6
+		for atomic.Loaduintptr(&n.key) == 0 {
+			semasleep(ns)
+			asmcgocall(*cgo_yield, nil)
+		}
+	}
+	gp.m.blocked = false
+}
+
+//go:nosplit
+func notetsleep_internal(n *note, ns int64, gp *g, deadline int64) bool {
+	// gp and deadline are logically local variables, but they are written
+	// as parameters so that the stack space they require is charged
+	// to the caller.
+	// This reduces the nosplit footprint of notetsleep_internal.
+	gp = getg()
+
+	// Register for wakeup on n->waitm.
+	if !atomic.Casuintptr(&n.key, 0, uintptr(unsafe.Pointer(gp.m))) {
+		// Must be locked (got wakeup).
+		if n.key != locked {
+			throw("notetsleep - waitm out of sync")
+		}
+		return true
+	}
+	if ns < 0 {
+		// Queued. Sleep.
+		gp.m.blocked = true
+		if *cgo_yield == nil {
+			semasleep(-1)
+		} else {
+			// Sleep in arbitrary-but-moderate intervals to poll libc interceptors.
+			const ns = 10e6
+			for semasleep(ns) < 0 {
+				asmcgocall(*cgo_yield, nil)
+			}
+		}
+		gp.m.blocked = false
+		return true
+	}
+
+	deadline = nanotime() + ns
+	for {
+		// Registered. Sleep.
+		gp.m.blocked = true
+		if *cgo_yield != nil && ns > 10e6 {
+			ns = 10e6
+		}
+		if semasleep(ns) >= 0 {
+			gp.m.blocked = false
+			// Acquired semaphore, semawakeup unregistered us.
+			// Done.
+			return true
+		}
+		if *cgo_yield != nil {
+			asmcgocall(*cgo_yield, nil)
+		}
+		gp.m.blocked = false
+		// Interrupted or timed out. Still registered. Semaphore not acquired.
+		ns = deadline - nanotime()
+		if ns <= 0 {
+			break
+		}
+		// Deadline hasn't arrived. Keep sleeping.
+	}
+
+	// Deadline arrived. Still registered. Semaphore not acquired.
+	// Want to give up and return, but have to unregister first,
+	// so that any notewakeup racing with the return does not
+	// try to grant us the semaphore when we don't expect it.
+	for {
+		v := atomic.Loaduintptr(&n.key)
+		switch v {
+		case uintptr(unsafe.Pointer(gp.m)):
+			// No wakeup yet; unregister if possible.
+			if atomic.Casuintptr(&n.key, v, 0) {
+				return false
+			}
+		case locked:
+			// Wakeup happened so semaphore is available.
+			// Grab it to avoid getting out of sync.
+			gp.m.blocked = true
+			if semasleep(-1) < 0 {
+				throw("runtime: unable to acquire - semaphore out of sync")
+			}
+			gp.m.blocked = false
+			return true
+		default:
+			throw("runtime: unexpected waitm - semaphore out of sync")
+		}
+	}
+}
+
+func notetsleep(n *note, ns int64) bool {
+	gp := getg()
+	if gp != gp.m.g0 {
+		throw("notetsleep not on g0")
+	}
+	semacreate(gp.m)
+	return notetsleep_internal(n, ns, nil, 0)
+}
+
+// same as runtime·notetsleep, but called on user g (not g0)
+// calls only nosplit functions between entersyscallblock/exitsyscall
+func notetsleepg(n *note, ns int64) bool {
+	gp := getg()
+	if gp == gp.m.g0 {
+		throw("notetsleepg on g0")
+	}
+	semacreate(gp.m)
+	entersyscallblock()
+	ok := notetsleep_internal(n, ns, nil, 0)
+	exitsyscall()
+	return ok
+}
+
+func beforeIdle(int64, int64) (*g, bool) {
+	return nil, false
+}
+
+func checkTimeouts() {}
diff --git a/contrib/go/_std_1.19/src/runtime/lockrank.go b/contrib/go/_std_1.19/src/runtime/lockrank.go
new file mode 100644
index 0000000000..bb0b189fc7
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/lockrank.go
@@ -0,0 +1,260 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file records the static ranks of the locks in the runtime. If a lock
+// is not given a rank, then it is assumed to be a leaf lock, which means no other
+// lock can be acquired while it is held. Therefore, leaf locks do not need to be
+// given an explicit rank. We list all of the architecture-independent leaf locks
+// for documentation purposes, but don't list any of the architecture-dependent
+// locks (which are all leaf locks). debugLock is ignored for ranking, since it is used
+// when printing out lock ranking errors.
+//
+// lockInit(l *mutex, rank int) is used to set the rank of lock before it is used.
+// If there is no clear place to initialize a lock, then the rank of a lock can be
+// specified during the lock call itself via lockWithrank(l *mutex, rank int).
+//
+// Besides the static lock ranking (which is a total ordering of the locks), we
+// also represent and enforce the actual partial order among the locks in the
+// arcs[] array below. That is, if it is possible that lock B can be acquired when
+// lock A is the previous acquired lock that is still held, then there should be
+// an entry for A in arcs[B][]. We will currently fail not only if the total order
+// (the lock ranking) is violated, but also if there is a missing entry in the
+// partial order.
+
+package runtime
+
+type lockRank int
+
+// Constants representing the lock rank of the architecture-independent locks in
+// the runtime. Locks with lower rank must be taken before locks with higher
+// rank.
+const (
+	lockRankDummy lockRank = iota
+
+	// Locks held above sched
+	lockRankSysmon
+	lockRankScavenge
+	lockRankForcegc
+	lockRankSweepWaiters
+	lockRankAssistQueue
+	lockRankCpuprof
+	lockRankSweep
+
+	lockRankPollDesc
+	lockRankSched
+	lockRankDeadlock
+	lockRankAllg
+	lockRankAllp
+
+	lockRankTimers // Multiple timers locked simultaneously in destroy()
+	lockRankItab
+	lockRankReflectOffs
+	lockRankHchan // Multiple hchans acquired in lock order in syncadjustsudogs()
+	lockRankTraceBuf
+	lockRankFin
+	lockRankNotifyList
+	lockRankTraceStrings
+	lockRankMspanSpecial
+	lockRankProfInsert
+	lockRankProfBlock
+	lockRankProfMemActive
+	lockRankProfMemFuture
+	lockRankGcBitsArenas
+	lockRankRoot
+	lockRankTrace
+	lockRankTraceStackTab
+	lockRankNetpollInit
+
+	lockRankRwmutexW
+	lockRankRwmutexR
+
+	lockRankSpanSetSpine
+	lockRankGscan
+	lockRankStackpool
+	lockRankStackLarge
+	lockRankDefer
+	lockRankSudog
+
+	// Memory-related non-leaf locks
+	lockRankWbufSpans
+	lockRankMheap
+	lockRankMheapSpecial
+
+	// Memory-related leaf locks
+	lockRankGlobalAlloc
+	lockRankPageAllocScav
+
+	// Other leaf locks
+	lockRankGFree
+	// Generally, hchan must be acquired before gscan. But in one specific
+	// case (in syncadjustsudogs from markroot after the g has been suspended
+	// by suspendG), we allow gscan to be acquired, and then an hchan lock. To
+	// allow this case, we get this lockRankHchanLeaf rank in
+	// syncadjustsudogs(), rather than lockRankHchan. By using this special
+	// rank, we don't allow any further locks to be acquired other than more
+	// hchan locks.
+	lockRankHchanLeaf
+	lockRankPanic
+
+	// Leaf locks with no dependencies, so these constants are not actually used anywhere.
+	// There are other architecture-dependent leaf locks as well.
+	lockRankNewmHandoff
+	lockRankDebugPtrmask
+	lockRankFaketimeState
+	lockRankTicks
+	lockRankRaceFini
+	lockRankPollCache
+	lockRankDebug
+)
+
+// lockRankLeafRank is the rank of lock that does not have a declared rank, and hence is
+// a leaf lock.
+const lockRankLeafRank lockRank = 1000
+
+// lockNames gives the names associated with each of the above ranks
+var lockNames = []string{
+	lockRankDummy: "",
+
+	lockRankSysmon:       "sysmon",
+	lockRankScavenge:     "scavenge",
+	lockRankForcegc:      "forcegc",
+	lockRankSweepWaiters: "sweepWaiters",
+	lockRankAssistQueue:  "assistQueue",
+	lockRankCpuprof:      "cpuprof",
+	lockRankSweep:        "sweep",
+
+	lockRankPollDesc: "pollDesc",
+	lockRankSched:    "sched",
+	lockRankDeadlock: "deadlock",
+	lockRankAllg:     "allg",
+	lockRankAllp:     "allp",
+
+	lockRankTimers:      "timers",
+	lockRankItab:        "itab",
+	lockRankReflectOffs: "reflectOffs",
+
+	lockRankHchan:         "hchan",
+	lockRankTraceBuf:      "traceBuf",
+	lockRankFin:           "fin",
+	lockRankNotifyList:    "notifyList",
+	lockRankTraceStrings:  "traceStrings",
+	lockRankMspanSpecial:  "mspanSpecial",
+	lockRankProfInsert:    "profInsert",
+	lockRankProfBlock:     "profBlock",
+	lockRankProfMemActive: "profMemActive",
+	lockRankProfMemFuture: "profMemFuture",
+	lockRankGcBitsArenas:  "gcBitsArenas",
+	lockRankRoot:          "root",
+	lockRankTrace:         "trace",
+	lockRankTraceStackTab: "traceStackTab",
+	lockRankNetpollInit:   "netpollInit",
+
+	lockRankRwmutexW: "rwmutexW",
+	lockRankRwmutexR: "rwmutexR",
+
+	lockRankSpanSetSpine: "spanSetSpine",
+	lockRankGscan:        "gscan",
+	lockRankStackpool:    "stackpool",
+	lockRankStackLarge:   "stackLarge",
+	lockRankDefer:        "defer",
+	lockRankSudog:        "sudog",
+
+	lockRankWbufSpans:    "wbufSpans",
+	lockRankMheap:        "mheap",
+	lockRankMheapSpecial: "mheapSpecial",
+
+	lockRankGlobalAlloc:   "globalAlloc.mutex",
+	lockRankPageAllocScav: "pageAlloc.scav.lock",
+
+	lockRankGFree:     "gFree",
+	lockRankHchanLeaf: "hchanLeaf",
+	lockRankPanic:     "panic",
+
+	lockRankNewmHandoff:   "newmHandoff.lock",
+	lockRankDebugPtrmask:  "debugPtrmask.lock",
+	lockRankFaketimeState: "faketimeState.lock",
+	lockRankTicks:         "ticks.lock",
+	lockRankRaceFini:      "raceFiniLock",
+	lockRankPollCache:     "pollCache.lock",
+	lockRankDebug:         "debugLock",
+}
+
+func (rank lockRank) String() string {
+	if rank == 0 {
+		return "UNKNOWN"
+	}
+	if rank == lockRankLeafRank {
+		return "LEAF"
+	}
+	return lockNames[rank]
+}
+
+// lockPartialOrder is a partial order among the various lock types, listing the
+// immediate ordering that has actually been observed in the runtime. Each entry
+// (which corresponds to a particular lock rank) specifies the list of locks
+// that can already be held immediately "above" it.
+//
+// So, for example, the lockRankSched entry shows that all the locks preceding
+// it in rank can actually be held. The allp lock shows that only the sysmon or
+// sched lock can be held immediately above it when it is acquired.
+var lockPartialOrder [][]lockRank = [][]lockRank{
+	lockRankDummy:         {},
+	lockRankSysmon:        {},
+	lockRankScavenge:      {lockRankSysmon},
+	lockRankForcegc:       {lockRankSysmon},
+	lockRankSweepWaiters:  {},
+	lockRankAssistQueue:   {},
+	lockRankCpuprof:       {},
+	lockRankSweep:         {},
+	lockRankPollDesc:      {},
+	lockRankSched:         {lockRankSysmon, lockRankScavenge, lockRankForcegc, lockRankSweepWaiters, lockRankAssistQueue, lockRankCpuprof, lockRankSweep, lockRankPollDesc},
+	lockRankDeadlock:      {lockRankDeadlock},
+	lockRankAllg:          {lockRankSysmon, lockRankSched},
+	lockRankAllp:          {lockRankSysmon, lockRankSched},
+	lockRankTimers:        {lockRankSysmon, lockRankScavenge, lockRankPollDesc, lockRankSched, lockRankAllp, lockRankTimers},
+	lockRankItab:          {},
+	lockRankReflectOffs:   {lockRankItab},
+	lockRankHchan:         {lockRankScavenge, lockRankSweep, lockRankHchan},
+	lockRankTraceBuf:      {lockRankSysmon, lockRankScavenge},
+	lockRankFin:           {lockRankSysmon, lockRankScavenge, lockRankSched, lockRankAllg, lockRankTimers, lockRankReflectOffs, lockRankHchan, lockRankTraceBuf},
+	lockRankNotifyList:    {},
+	lockRankTraceStrings:  {lockRankTraceBuf},
+	lockRankMspanSpecial:  {lockRankSysmon, lockRankScavenge, lockRankAssistQueue, lockRankCpuprof, lockRankSweep, lockRankSched, lockRankAllg, lockRankAllp, lockRankTimers, lockRankItab, lockRankReflectOffs, lockRankHchan, lockRankTraceBuf, lockRankNotifyList, lockRankTraceStrings},
+	lockRankProfInsert:    {lockRankSysmon, lockRankScavenge, lockRankAssistQueue, lockRankCpuprof, lockRankSweep, lockRankSched, lockRankAllg, lockRankAllp, lockRankTimers, lockRankItab, lockRankReflectOffs, lockRankHchan, lockRankTraceBuf, lockRankNotifyList, lockRankTraceStrings},
+	lockRankProfBlock:     {lockRankSysmon, lockRankScavenge, lockRankAssistQueue, lockRankCpuprof, lockRankSweep, lockRankSched, lockRankAllg, lockRankAllp, lockRankTimers, lockRankItab, lockRankReflectOffs, lockRankHchan, lockRankTraceBuf, lockRankNotifyList, lockRankTraceStrings},
+	lockRankProfMemActive: {lockRankSysmon, lockRankScavenge, lockRankAssistQueue, lockRankCpuprof, lockRankSweep, lockRankSched, lockRankAllg, lockRankAllp, lockRankTimers, lockRankItab, lockRankReflectOffs, lockRankHchan, lockRankTraceBuf, lockRankNotifyList, lockRankTraceStrings},
+	lockRankProfMemFuture: {lockRankSysmon, lockRankScavenge, lockRankAssistQueue, lockRankCpuprof, lockRankSweep, lockRankSched, lockRankAllg, lockRankAllp, lockRankTimers, lockRankItab, lockRankReflectOffs, lockRankHchan, lockRankTraceBuf, lockRankNotifyList, lockRankTraceStrings, lockRankProfMemActive},
+	lockRankGcBitsArenas:  {lockRankSysmon, lockRankScavenge, lockRankAssistQueue, lockRankCpuprof, lockRankSched, lockRankAllg, lockRankTimers, lockRankItab, lockRankReflectOffs, lockRankHchan, lockRankTraceBuf, lockRankNotifyList, lockRankTraceStrings},
+	lockRankRoot:          {},
+	lockRankTrace:         {lockRankSysmon, lockRankScavenge, lockRankForcegc, lockRankAssistQueue, lockRankSweep, lockRankSched, lockRankHchan, lockRankTraceBuf, lockRankTraceStrings, lockRankRoot},
+	lockRankTraceStackTab: {lockRankScavenge, lockRankForcegc, lockRankSweepWaiters, lockRankAssistQueue, lockRankSweep, lockRankSched, lockRankAllg, lockRankTimers, lockRankHchan, lockRankTraceBuf, lockRankFin, lockRankNotifyList, lockRankTraceStrings, lockRankRoot, lockRankTrace},
+	lockRankNetpollInit:   {lockRankTimers},
+
+	lockRankRwmutexW: {},
+	lockRankRwmutexR: {lockRankSysmon, lockRankRwmutexW},
+
+	lockRankSpanSetSpine:  {lockRankSysmon, lockRankScavenge, lockRankForcegc, lockRankAssistQueue, lockRankCpuprof, lockRankSweep, lockRankPollDesc, lockRankSched, lockRankAllg, lockRankAllp, lockRankTimers, lockRankItab, lockRankReflectOffs, lockRankHchan, lockRankTraceBuf, lockRankNotifyList, lockRankTraceStrings},
+	lockRankGscan:         {lockRankSysmon, lockRankScavenge, lockRankForcegc, lockRankSweepWaiters, lockRankAssistQueue, lockRankCpuprof, lockRankSweep, lockRankPollDesc, lockRankSched, lockRankTimers, lockRankItab, lockRankReflectOffs, lockRankHchan, lockRankTraceBuf, lockRankFin, lockRankNotifyList, lockRankTraceStrings, lockRankProfInsert, lockRankProfBlock, lockRankProfMemActive, lockRankProfMemFuture, lockRankGcBitsArenas, lockRankRoot, lockRankTrace, lockRankTraceStackTab, lockRankNetpollInit, lockRankSpanSetSpine},
+	lockRankStackpool:     {lockRankSysmon, lockRankScavenge, lockRankSweepWaiters, lockRankAssistQueue, lockRankCpuprof, lockRankSweep, lockRankPollDesc, lockRankSched, lockRankTimers, lockRankItab, lockRankReflectOffs, lockRankHchan, lockRankTraceBuf, lockRankFin, lockRankNotifyList, lockRankTraceStrings, lockRankProfInsert, lockRankProfBlock, lockRankProfMemActive, lockRankProfMemFuture, lockRankGcBitsArenas, lockRankRoot, lockRankTrace, lockRankTraceStackTab, lockRankNetpollInit, lockRankRwmutexR, lockRankSpanSetSpine, lockRankGscan},
+	lockRankStackLarge:    {lockRankSysmon, lockRankAssistQueue, lockRankSched, lockRankItab, lockRankHchan, lockRankProfInsert, lockRankProfBlock, lockRankProfMemActive, lockRankProfMemFuture, lockRankGcBitsArenas, lockRankRoot, lockRankSpanSetSpine, lockRankGscan},
+	lockRankDefer:         {},
+	lockRankSudog:         {lockRankHchan, lockRankNotifyList},
+	lockRankWbufSpans:     {lockRankSysmon, lockRankScavenge, lockRankSweepWaiters, lockRankAssistQueue, lockRankSweep, lockRankPollDesc, lockRankSched, lockRankAllg, lockRankTimers, lockRankItab, lockRankReflectOffs, lockRankHchan, lockRankFin, lockRankNotifyList, lockRankTraceStrings, lockRankMspanSpecial, lockRankProfInsert, lockRankProfBlock, lockRankProfMemActive, lockRankProfMemFuture, lockRankRoot, lockRankTrace, lockRankGscan, lockRankDefer, lockRankSudog},
+	lockRankMheap:         {lockRankSysmon, lockRankScavenge, lockRankSweepWaiters, lockRankAssistQueue, lockRankCpuprof, lockRankSweep, lockRankPollDesc, lockRankSched, lockRankAllg, lockRankAllp, lockRankTimers, lockRankItab, lockRankReflectOffs, lockRankHchan, lockRankTraceBuf, lockRankFin, lockRankNotifyList, lockRankTraceStrings, lockRankMspanSpecial, lockRankProfInsert, lockRankProfBlock, lockRankProfMemActive, lockRankProfMemFuture, lockRankGcBitsArenas, lockRankRoot, lockRankTrace, lockRankSpanSetSpine, lockRankGscan, lockRankStackpool, lockRankStackLarge, lockRankDefer, lockRankSudog, lockRankWbufSpans},
+	lockRankMheapSpecial:  {lockRankSysmon, lockRankScavenge, lockRankAssistQueue, lockRankCpuprof, lockRankSweep, lockRankPollDesc, lockRankSched, lockRankAllg, lockRankAllp, lockRankTimers, lockRankItab, lockRankReflectOffs, lockRankHchan, lockRankTraceBuf, lockRankNotifyList, lockRankTraceStrings},
+	lockRankGlobalAlloc:   {lockRankProfInsert, lockRankProfBlock, lockRankProfMemActive, lockRankProfMemFuture, lockRankSpanSetSpine, lockRankMheap, lockRankMheapSpecial},
+	lockRankPageAllocScav: {lockRankMheap},
+
+	lockRankGFree:     {lockRankSched},
+	lockRankHchanLeaf: {lockRankGscan, lockRankHchanLeaf},
+	lockRankPanic:     {lockRankDeadlock}, // plus any other lock held on throw.
+
+	lockRankNewmHandoff:   {},
+	lockRankDebugPtrmask:  {},
+	lockRankFaketimeState: {},
+	lockRankTicks:         {},
+	lockRankRaceFini:      {},
+	lockRankPollCache:     {},
+	lockRankDebug:         {},
+}
diff --git a/contrib/go/_std_1.19/src/runtime/lockrank_off.go b/contrib/go/_std_1.19/src/runtime/lockrank_off.go
new file mode 100644
index 0000000000..bf046a1041
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/lockrank_off.go
@@ -0,0 +1,66 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !goexperiment.staticlockranking
+
+package runtime
+
+// // lockRankStruct is embedded in mutex, but is empty when staticklockranking is
+// disabled (the default)
+type lockRankStruct struct {
+}
+
+func lockInit(l *mutex, rank lockRank) {
+}
+
+func getLockRank(l *mutex) lockRank {
+	return 0
+}
+
+func lockWithRank(l *mutex, rank lockRank) {
+	lock2(l)
+}
+
+// This function may be called in nosplit context and thus must be nosplit.
+//
+//go:nosplit
+func acquireLockRank(rank lockRank) {
+}
+
+func unlockWithRank(l *mutex) {
+	unlock2(l)
+}
+
+// This function may be called in nosplit context and thus must be nosplit.
+//
+//go:nosplit
+func releaseLockRank(rank lockRank) {
+}
+
+func lockWithRankMayAcquire(l *mutex, rank lockRank) {
+}
+
+//go:nosplit
+func assertLockHeld(l *mutex) {
+}
+
+//go:nosplit
+func assertRankHeld(r lockRank) {
+}
+
+//go:nosplit
+func worldStopped() {
+}
+
+//go:nosplit
+func worldStarted() {
+}
+
+//go:nosplit
+func assertWorldStopped() {
+}
+
+//go:nosplit
+func assertWorldStoppedOrLockHeld(l *mutex) {
+}
diff --git a/contrib/go/_std_1.19/src/runtime/malloc.go b/contrib/go/_std_1.19/src/runtime/malloc.go
new file mode 100644
index 0000000000..eb24fdb0e8
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/malloc.go
@@ -0,0 +1,1501 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Memory allocator.
+//
+// This was originally based on tcmalloc, but has diverged quite a bit.
+// http://goog-perftools.sourceforge.net/doc/tcmalloc.html
+
+// The main allocator works in runs of pages.
+// Small allocation sizes (up to and including 32 kB) are
+// rounded to one of about 70 size classes, each of which
+// has its own free set of objects of exactly that size.
+// Any free page of memory can be split into a set of objects
+// of one size class, which are then managed using a free bitmap.
+//
+// The allocator's data structures are:
+//
+//	fixalloc: a free-list allocator for fixed-size off-heap objects,
+//		used to manage storage used by the allocator.
+//	mheap: the malloc heap, managed at page (8192-byte) granularity.
+//	mspan: a run of in-use pages managed by the mheap.
+//	mcentral: collects all spans of a given size class.
+//	mcache: a per-P cache of mspans with free space.
+//	mstats: allocation statistics.
+//
+// Allocating a small object proceeds up a hierarchy of caches:
+//
+//	1. Round the size up to one of the small size classes
+//	   and look in the corresponding mspan in this P's mcache.
+//	   Scan the mspan's free bitmap to find a free slot.
+//	   If there is a free slot, allocate it.
+//	   This can all be done without acquiring a lock.
+//
+//	2. If the mspan has no free slots, obtain a new mspan
+//	   from the mcentral's list of mspans of the required size
+//	   class that have free space.
+//	   Obtaining a whole span amortizes the cost of locking
+//	   the mcentral.
+//
+//	3. If the mcentral's mspan list is empty, obtain a run
+//	   of pages from the mheap to use for the mspan.
+//
+//	4. If the mheap is empty or has no page runs large enough,
+//	   allocate a new group of pages (at least 1MB) from the
+//	   operating system. Allocating a large run of pages
+//	   amortizes the cost of talking to the operating system.
+//
+// Sweeping an mspan and freeing objects on it proceeds up a similar
+// hierarchy:
+//
+//	1. If the mspan is being swept in response to allocation, it
+//	   is returned to the mcache to satisfy the allocation.
+//
+//	2. Otherwise, if the mspan still has allocated objects in it,
+//	   it is placed on the mcentral free list for the mspan's size
+//	   class.
+//
+//	3. Otherwise, if all objects in the mspan are free, the mspan's
+//	   pages are returned to the mheap and the mspan is now dead.
+//
+// Allocating and freeing a large object uses the mheap
+// directly, bypassing the mcache and mcentral.
+//
+// If mspan.needzero is false, then free object slots in the mspan are
+// already zeroed. Otherwise if needzero is true, objects are zeroed as
+// they are allocated. There are various benefits to delaying zeroing
+// this way:
+//
+//	1. Stack frame allocation can avoid zeroing altogether.
+//
+//	2. It exhibits better temporal locality, since the program is
+//	   probably about to write to the memory.
+//
+//	3. We don't zero pages that never get reused.
+
+// Virtual memory layout
+//
+// The heap consists of a set of arenas, which are 64MB on 64-bit and
+// 4MB on 32-bit (heapArenaBytes). Each arena's start address is also
+// aligned to the arena size.
+//
+// Each arena has an associated heapArena object that stores the
+// metadata for that arena: the heap bitmap for all words in the arena
+// and the span map for all pages in the arena. heapArena objects are
+// themselves allocated off-heap.
+//
+// Since arenas are aligned, the address space can be viewed as a
+// series of arena frames. The arena map (mheap_.arenas) maps from
+// arena frame number to *heapArena, or nil for parts of the address
+// space not backed by the Go heap. The arena map is structured as a
+// two-level array consisting of a "L1" arena map and many "L2" arena
+// maps; however, since arenas are large, on many architectures, the
+// arena map consists of a single, large L2 map.
+//
+// The arena map covers the entire possible address space, allowing
+// the Go heap to use any part of the address space. The allocator
+// attempts to keep arenas contiguous so that large spans (and hence
+// large objects) can cross arenas.
+
+package runtime
+
+import (
+	"internal/goarch"
+	"internal/goos"
+	"runtime/internal/atomic"
+	"runtime/internal/math"
+	"runtime/internal/sys"
+	"unsafe"
+)
+
+const (
+	maxTinySize   = _TinySize
+	tinySizeClass = _TinySizeClass
+	maxSmallSize  = _MaxSmallSize
+
+	pageShift = _PageShift
+	pageSize  = _PageSize
+
+	concurrentSweep = _ConcurrentSweep
+
+	_PageSize = 1 << _PageShift
+	_PageMask = _PageSize - 1
+
+	// _64bit = 1 on 64-bit systems, 0 on 32-bit systems
+	_64bit = 1 << (^uintptr(0) >> 63) / 2
+
+	// Tiny allocator parameters, see "Tiny allocator" comment in malloc.go.
+	_TinySize      = 16
+	_TinySizeClass = int8(2)
+
+	_FixAllocChunk = 16 << 10 // Chunk size for FixAlloc
+
+	// Per-P, per order stack segment cache size.
+	_StackCacheSize = 32 * 1024
+
+	// Number of orders that get caching. Order 0 is FixedStack
+	// and each successive order is twice as large.
+	// We want to cache 2KB, 4KB, 8KB, and 16KB stacks. Larger stacks
+	// will be allocated directly.
+	// Since FixedStack is different on different systems, we
+	// must vary NumStackOrders to keep the same maximum cached size.
+	//   OS               | FixedStack | NumStackOrders
+	//   -----------------+------------+---------------
+	//   linux/darwin/bsd | 2KB        | 4
+	//   windows/32       | 4KB        | 3
+	//   windows/64       | 8KB        | 2
+	//   plan9            | 4KB        | 3
+	_NumStackOrders = 4 - goarch.PtrSize/4*goos.IsWindows - 1*goos.IsPlan9
+
+	// heapAddrBits is the number of bits in a heap address. On
+	// amd64, addresses are sign-extended beyond heapAddrBits. On
+	// other arches, they are zero-extended.
+	//
+	// On most 64-bit platforms, we limit this to 48 bits based on a
+	// combination of hardware and OS limitations.
+	//
+	// amd64 hardware limits addresses to 48 bits, sign-extended
+	// to 64 bits. Addresses where the top 16 bits are not either
+	// all 0 or all 1 are "non-canonical" and invalid. Because of
+	// these "negative" addresses, we offset addresses by 1<<47
+	// (arenaBaseOffset) on amd64 before computing indexes into
+	// the heap arenas index. In 2017, amd64 hardware added
+	// support for 57 bit addresses; however, currently only Linux
+	// supports this extension and the kernel will never choose an
+	// address above 1<<47 unless mmap is called with a hint
+	// address above 1<<47 (which we never do).
+	//
+	// arm64 hardware (as of ARMv8) limits user addresses to 48
+	// bits, in the range [0, 1<<48).
+	//
+	// ppc64, mips64, and s390x support arbitrary 64 bit addresses
+	// in hardware. On Linux, Go leans on stricter OS limits. Based
+	// on Linux's processor.h, the user address space is limited as
+	// follows on 64-bit architectures:
+	//
+	// Architecture  Name              Maximum Value (exclusive)
+	// ---------------------------------------------------------------------
+	// amd64         TASK_SIZE_MAX     0x007ffffffff000 (47 bit addresses)
+	// arm64         TASK_SIZE_64      0x01000000000000 (48 bit addresses)
+	// ppc64{,le}    TASK_SIZE_USER64  0x00400000000000 (46 bit addresses)
+	// mips64{,le}   TASK_SIZE64       0x00010000000000 (40 bit addresses)
+	// s390x         TASK_SIZE         1<<64 (64 bit addresses)
+	//
+	// These limits may increase over time, but are currently at
+	// most 48 bits except on s390x. On all architectures, Linux
+	// starts placing mmap'd regions at addresses that are
+	// significantly below 48 bits, so even if it's possible to
+	// exceed Go's 48 bit limit, it's extremely unlikely in
+	// practice.
+	//
+	// On 32-bit platforms, we accept the full 32-bit address
+	// space because doing so is cheap.
+	// mips32 only has access to the low 2GB of virtual memory, so
+	// we further limit it to 31 bits.
+	//
+	// On ios/arm64, although 64-bit pointers are presumably
+	// available, pointers are truncated to 33 bits in iOS <14.
+	// Furthermore, only the top 4 GiB of the address space are
+	// actually available to the application. In iOS >=14, more
+	// of the address space is available, and the OS can now
+	// provide addresses outside of those 33 bits. Pick 40 bits
+	// as a reasonable balance between address space usage by the
+	// page allocator, and flexibility for what mmap'd regions
+	// we'll accept for the heap. We can't just move to the full
+	// 48 bits because this uses too much address space for older
+	// iOS versions.
+	// TODO(mknyszek): Once iOS <14 is deprecated, promote ios/arm64
+	// to a 48-bit address space like every other arm64 platform.
+	//
+	// WebAssembly currently has a limit of 4GB linear memory.
+	heapAddrBits = (_64bit*(1-goarch.IsWasm)*(1-goos.IsIos*goarch.IsArm64))*48 + (1-_64bit+goarch.IsWasm)*(32-(goarch.IsMips+goarch.IsMipsle)) + 40*goos.IsIos*goarch.IsArm64
+
+	// maxAlloc is the maximum size of an allocation. On 64-bit,
+	// it's theoretically possible to allocate 1<<heapAddrBits bytes. On
+	// 32-bit, however, this is one less than 1<<32 because the
+	// number of bytes in the address space doesn't actually fit
+	// in a uintptr.
+	maxAlloc = (1 << heapAddrBits) - (1-_64bit)*1
+
+	// The number of bits in a heap address, the size of heap
+	// arenas, and the L1 and L2 arena map sizes are related by
+	//
+	//   (1 << addr bits) = arena size * L1 entries * L2 entries
+	//
+	// Currently, we balance these as follows:
+	//
+	//       Platform  Addr bits  Arena size  L1 entries   L2 entries
+	// --------------  ---------  ----------  ----------  -----------
+	//       */64-bit         48        64MB           1    4M (32MB)
+	// windows/64-bit         48         4MB          64    1M  (8MB)
+	//      ios/arm64         33         4MB           1  2048  (8KB)
+	//       */32-bit         32         4MB           1  1024  (4KB)
+	//     */mips(le)         31         4MB           1   512  (2KB)
+
+	// heapArenaBytes is the size of a heap arena. The heap
+	// consists of mappings of size heapArenaBytes, aligned to
+	// heapArenaBytes. The initial heap mapping is one arena.
+	//
+	// This is currently 64MB on 64-bit non-Windows and 4MB on
+	// 32-bit and on Windows. We use smaller arenas on Windows
+	// because all committed memory is charged to the process,
+	// even if it's not touched. Hence, for processes with small
+	// heaps, the mapped arena space needs to be commensurate.
+	// This is particularly important with the race detector,
+	// since it significantly amplifies the cost of committed
+	// memory.
+	heapArenaBytes = 1 << logHeapArenaBytes
+
+	// logHeapArenaBytes is log_2 of heapArenaBytes. For clarity,
+	// prefer using heapArenaBytes where possible (we need the
+	// constant to compute some other constants).
+	logHeapArenaBytes = (6+20)*(_64bit*(1-goos.IsWindows)*(1-goarch.IsWasm)*(1-goos.IsIos*goarch.IsArm64)) + (2+20)*(_64bit*goos.IsWindows) + (2+20)*(1-_64bit) + (2+20)*goarch.IsWasm + (2+20)*goos.IsIos*goarch.IsArm64
+
+	// heapArenaBitmapBytes is the size of each heap arena's bitmap.
+	heapArenaBitmapBytes = heapArenaBytes / (goarch.PtrSize * 8 / 2)
+
+	pagesPerArena = heapArenaBytes / pageSize
+
+	// arenaL1Bits is the number of bits of the arena number
+	// covered by the first level arena map.
+	//
+	// This number should be small, since the first level arena
+	// map requires PtrSize*(1<<arenaL1Bits) of space in the
+	// binary's BSS. It can be zero, in which case the first level
+	// index is effectively unused. There is a performance benefit
+	// to this, since the generated code can be more efficient,
+	// but comes at the cost of having a large L2 mapping.
+	//
+	// We use the L1 map on 64-bit Windows because the arena size
+	// is small, but the address space is still 48 bits, and
+	// there's a high cost to having a large L2.
+	arenaL1Bits = 6 * (_64bit * goos.IsWindows)
+
+	// arenaL2Bits is the number of bits of the arena number
+	// covered by the second level arena index.
+	//
+	// The size of each arena map allocation is proportional to
+	// 1<<arenaL2Bits, so it's important that this not be too
+	// large. 48 bits leads to 32MB arena index allocations, which
+	// is about the practical threshold.
+	arenaL2Bits = heapAddrBits - logHeapArenaBytes - arenaL1Bits
+
+	// arenaL1Shift is the number of bits to shift an arena frame
+	// number by to compute an index into the first level arena map.
+	arenaL1Shift = arenaL2Bits
+
+	// arenaBits is the total bits in a combined arena map index.
+	// This is split between the index into the L1 arena map and
+	// the L2 arena map.
+	arenaBits = arenaL1Bits + arenaL2Bits
+
+	// arenaBaseOffset is the pointer value that corresponds to
+	// index 0 in the heap arena map.
+	//
+	// On amd64, the address space is 48 bits, sign extended to 64
+	// bits. This offset lets us handle "negative" addresses (or
+	// high addresses if viewed as unsigned).
+	//
+	// On aix/ppc64, this offset allows to keep the heapAddrBits to
+	// 48. Otherwise, it would be 60 in order to handle mmap addresses
+	// (in range 0x0a00000000000000 - 0x0afffffffffffff). But in this
+	// case, the memory reserved in (s *pageAlloc).init for chunks
+	// is causing important slowdowns.
+	//
+	// On other platforms, the user address space is contiguous
+	// and starts at 0, so no offset is necessary.
+	arenaBaseOffset = 0xffff800000000000*goarch.IsAmd64 + 0x0a00000000000000*goos.IsAix
+	// A typed version of this constant that will make it into DWARF (for viewcore).
+	arenaBaseOffsetUintptr = uintptr(arenaBaseOffset)
+
+	// Max number of threads to run garbage collection.
+	// 2, 3, and 4 are all plausible maximums depending
+	// on the hardware details of the machine. The garbage
+	// collector scales well to 32 cpus.
+	_MaxGcproc = 32
+
+	// minLegalPointer is the smallest possible legal pointer.
+	// This is the smallest possible architectural page size,
+	// since we assume that the first page is never mapped.
+	//
+	// This should agree with minZeroPage in the compiler.
+	minLegalPointer uintptr = 4096
+)
+
+// physPageSize is the size in bytes of the OS's physical pages.
+// Mapping and unmapping operations must be done at multiples of
+// physPageSize.
+//
+// This must be set by the OS init code (typically in osinit) before
+// mallocinit.
+var physPageSize uintptr
+
+// physHugePageSize is the size in bytes of the OS's default physical huge
+// page size whose allocation is opaque to the application. It is assumed
+// and verified to be a power of two.
+//
+// If set, this must be set by the OS init code (typically in osinit) before
+// mallocinit. However, setting it at all is optional, and leaving the default
+// value is always safe (though potentially less efficient).
+//
+// Since physHugePageSize is always assumed to be a power of two,
+// physHugePageShift is defined as physHugePageSize == 1 << physHugePageShift.
+// The purpose of physHugePageShift is to avoid doing divisions in
+// performance critical functions.
+var (
+	physHugePageSize  uintptr
+	physHugePageShift uint
+)
+
+func mallocinit() {
+	if class_to_size[_TinySizeClass] != _TinySize {
+		throw("bad TinySizeClass")
+	}
+
+	if heapArenaBitmapBytes&(heapArenaBitmapBytes-1) != 0 {
+		// heapBits expects modular arithmetic on bitmap
+		// addresses to work.
+		throw("heapArenaBitmapBytes not a power of 2")
+	}
+
+	// Check physPageSize.
+	if physPageSize == 0 {
+		// The OS init code failed to fetch the physical page size.
+		throw("failed to get system page size")
+	}
+	if physPageSize > maxPhysPageSize {
+		print("system page size (", physPageSize, ") is larger than maximum page size (", maxPhysPageSize, ")\n")
+		throw("bad system page size")
+	}
+	if physPageSize < minPhysPageSize {
+		print("system page size (", physPageSize, ") is smaller than minimum page size (", minPhysPageSize, ")\n")
+		throw("bad system page size")
+	}
+	if physPageSize&(physPageSize-1) != 0 {
+		print("system page size (", physPageSize, ") must be a power of 2\n")
+		throw("bad system page size")
+	}
+	if physHugePageSize&(physHugePageSize-1) != 0 {
+		print("system huge page size (", physHugePageSize, ") must be a power of 2\n")
+		throw("bad system huge page size")
+	}
+	if physHugePageSize > maxPhysHugePageSize {
+		// physHugePageSize is greater than the maximum supported huge page size.
+		// Don't throw here, like in the other cases, since a system configured
+		// in this way isn't wrong, we just don't have the code to support them.
+		// Instead, silently set the huge page size to zero.
+		physHugePageSize = 0
+	}
+	if physHugePageSize != 0 {
+		// Since physHugePageSize is a power of 2, it suffices to increase
+		// physHugePageShift until 1<<physHugePageShift == physHugePageSize.
+		for 1<<physHugePageShift != physHugePageSize {
+			physHugePageShift++
+		}
+	}
+	if pagesPerArena%pagesPerSpanRoot != 0 {
+		print("pagesPerArena (", pagesPerArena, ") is not divisible by pagesPerSpanRoot (", pagesPerSpanRoot, ")\n")
+		throw("bad pagesPerSpanRoot")
+	}
+	if pagesPerArena%pagesPerReclaimerChunk != 0 {
+		print("pagesPerArena (", pagesPerArena, ") is not divisible by pagesPerReclaimerChunk (", pagesPerReclaimerChunk, ")\n")
+		throw("bad pagesPerReclaimerChunk")
+	}
+
+	// Initialize the heap.
+	mheap_.init()
+	mcache0 = allocmcache()
+	lockInit(&gcBitsArenas.lock, lockRankGcBitsArenas)
+	lockInit(&profInsertLock, lockRankProfInsert)
+	lockInit(&profBlockLock, lockRankProfBlock)
+	lockInit(&profMemActiveLock, lockRankProfMemActive)
+	for i := range profMemFutureLock {
+		lockInit(&profMemFutureLock[i], lockRankProfMemFuture)
+	}
+	lockInit(&globalAlloc.mutex, lockRankGlobalAlloc)
+
+	// Create initial arena growth hints.
+	if goarch.PtrSize == 8 {
+		// On a 64-bit machine, we pick the following hints
+		// because:
+		//
+		// 1. Starting from the middle of the address space
+		// makes it easier to grow out a contiguous range
+		// without running in to some other mapping.
+		//
+		// 2. This makes Go heap addresses more easily
+		// recognizable when debugging.
+		//
+		// 3. Stack scanning in gccgo is still conservative,
+		// so it's important that addresses be distinguishable
+		// from other data.
+		//
+		// Starting at 0x00c0 means that the valid memory addresses
+		// will begin 0x00c0, 0x00c1, ...
+		// In little-endian, that's c0 00, c1 00, ... None of those are valid
+		// UTF-8 sequences, and they are otherwise as far away from
+		// ff (likely a common byte) as possible. If that fails, we try other 0xXXc0
+		// addresses. An earlier attempt to use 0x11f8 caused out of memory errors
+		// on OS X during thread allocations.  0x00c0 causes conflicts with
+		// AddressSanitizer which reserves all memory up to 0x0100.
+		// These choices reduce the odds of a conservative garbage collector
+		// not collecting memory because some non-pointer block of memory
+		// had a bit pattern that matched a memory address.
+		//
+		// However, on arm64, we ignore all this advice above and slam the
+		// allocation at 0x40 << 32 because when using 4k pages with 3-level
+		// translation buffers, the user address space is limited to 39 bits
+		// On ios/arm64, the address space is even smaller.
+		//
+		// On AIX, mmaps starts at 0x0A00000000000000 for 64-bit.
+		// processes.
+		for i := 0x7f; i >= 0; i-- {
+			var p uintptr
+			switch {
+			case raceenabled:
+				// The TSAN runtime requires the heap
+				// to be in the range [0x00c000000000,
+				// 0x00e000000000).
+				p = uintptr(i)<<32 | uintptrMask&(0x00c0<<32)
+				if p >= uintptrMask&0x00e000000000 {
+					continue
+				}
+			case GOARCH == "arm64" && GOOS == "ios":
+				p = uintptr(i)<<40 | uintptrMask&(0x0013<<28)
+			case GOARCH == "arm64":
+				p = uintptr(i)<<40 | uintptrMask&(0x0040<<32)
+			case GOOS == "aix":
+				if i == 0 {
+					// We don't use addresses directly after 0x0A00000000000000
+					// to avoid collisions with others mmaps done by non-go programs.
+					continue
+				}
+				p = uintptr(i)<<40 | uintptrMask&(0xa0<<52)
+			default:
+				p = uintptr(i)<<40 | uintptrMask&(0x00c0<<32)
+			}
+			hint := (*arenaHint)(mheap_.arenaHintAlloc.alloc())
+			hint.addr = p
+			hint.next, mheap_.arenaHints = mheap_.arenaHints, hint
+		}
+	} else {
+		// On a 32-bit machine, we're much more concerned
+		// about keeping the usable heap contiguous.
+		// Hence:
+		//
+		// 1. We reserve space for all heapArenas up front so
+		// they don't get interleaved with the heap. They're
+		// ~258MB, so this isn't too bad. (We could reserve a
+		// smaller amount of space up front if this is a
+		// problem.)
+		//
+		// 2. We hint the heap to start right above the end of
+		// the binary so we have the best chance of keeping it
+		// contiguous.
+		//
+		// 3. We try to stake out a reasonably large initial
+		// heap reservation.
+
+		const arenaMetaSize = (1 << arenaBits) * unsafe.Sizeof(heapArena{})
+		meta := uintptr(sysReserve(nil, arenaMetaSize))
+		if meta != 0 {
+			mheap_.heapArenaAlloc.init(meta, arenaMetaSize, true)
+		}
+
+		// We want to start the arena low, but if we're linked
+		// against C code, it's possible global constructors
+		// have called malloc and adjusted the process' brk.
+		// Query the brk so we can avoid trying to map the
+		// region over it (which will cause the kernel to put
+		// the region somewhere else, likely at a high
+		// address).
+		procBrk := sbrk0()
+
+		// If we ask for the end of the data segment but the
+		// operating system requires a little more space
+		// before we can start allocating, it will give out a
+		// slightly higher pointer. Except QEMU, which is
+		// buggy, as usual: it won't adjust the pointer
+		// upward. So adjust it upward a little bit ourselves:
+		// 1/4 MB to get away from the running binary image.
+		p := firstmoduledata.end
+		if p < procBrk {
+			p = procBrk
+		}
+		if mheap_.heapArenaAlloc.next <= p && p < mheap_.heapArenaAlloc.end {
+			p = mheap_.heapArenaAlloc.end
+		}
+		p = alignUp(p+(256<<10), heapArenaBytes)
+		// Because we're worried about fragmentation on
+		// 32-bit, we try to make a large initial reservation.
+		arenaSizes := []uintptr{
+			512 << 20,
+			256 << 20,
+			128 << 20,
+		}
+		for _, arenaSize := range arenaSizes {
+			a, size := sysReserveAligned(unsafe.Pointer(p), arenaSize, heapArenaBytes)
+			if a != nil {
+				mheap_.arena.init(uintptr(a), size, false)
+				p = mheap_.arena.end // For hint below
+				break
+			}
+		}
+		hint := (*arenaHint)(mheap_.arenaHintAlloc.alloc())
+		hint.addr = p
+		hint.next, mheap_.arenaHints = mheap_.arenaHints, hint
+	}
+}
+
+// sysAlloc allocates heap arena space for at least n bytes. The
+// returned pointer is always heapArenaBytes-aligned and backed by
+// h.arenas metadata. The returned size is always a multiple of
+// heapArenaBytes. sysAlloc returns nil on failure.
+// There is no corresponding free function.
+//
+// sysAlloc returns a memory region in the Reserved state. This region must
+// be transitioned to Prepared and then Ready before use.
+//
+// h must be locked.
+func (h *mheap) sysAlloc(n uintptr) (v unsafe.Pointer, size uintptr) {
+	assertLockHeld(&h.lock)
+
+	n = alignUp(n, heapArenaBytes)
+
+	// First, try the arena pre-reservation.
+	// Newly-used mappings are considered released.
+	v = h.arena.alloc(n, heapArenaBytes, &gcController.heapReleased)
+	if v != nil {
+		size = n
+		goto mapped
+	}
+
+	// Try to grow the heap at a hint address.
+	for h.arenaHints != nil {
+		hint := h.arenaHints
+		p := hint.addr
+		if hint.down {
+			p -= n
+		}
+		if p+n < p {
+			// We can't use this, so don't ask.
+			v = nil
+		} else if arenaIndex(p+n-1) >= 1<<arenaBits {
+			// Outside addressable heap. Can't use.
+			v = nil
+		} else {
+			v = sysReserve(unsafe.Pointer(p), n)
+		}
+		if p == uintptr(v) {
+			// Success. Update the hint.
+			if !hint.down {
+				p += n
+			}
+			hint.addr = p
+			size = n
+			break
+		}
+		// Failed. Discard this hint and try the next.
+		//
+		// TODO: This would be cleaner if sysReserve could be
+		// told to only return the requested address. In
+		// particular, this is already how Windows behaves, so
+		// it would simplify things there.
+		if v != nil {
+			sysFreeOS(v, n)
+		}
+		h.arenaHints = hint.next
+		h.arenaHintAlloc.free(unsafe.Pointer(hint))
+	}
+
+	if size == 0 {
+		if raceenabled {
+			// The race detector assumes the heap lives in
+			// [0x00c000000000, 0x00e000000000), but we
+			// just ran out of hints in this region. Give
+			// a nice failure.
+			throw("too many address space collisions for -race mode")
+		}
+
+		// All of the hints failed, so we'll take any
+		// (sufficiently aligned) address the kernel will give
+		// us.
+		v, size = sysReserveAligned(nil, n, heapArenaBytes)
+		if v == nil {
+			return nil, 0
+		}
+
+		// Create new hints for extending this region.
+		hint := (*arenaHint)(h.arenaHintAlloc.alloc())
+		hint.addr, hint.down = uintptr(v), true
+		hint.next, mheap_.arenaHints = mheap_.arenaHints, hint
+		hint = (*arenaHint)(h.arenaHintAlloc.alloc())
+		hint.addr = uintptr(v) + size
+		hint.next, mheap_.arenaHints = mheap_.arenaHints, hint
+	}
+
+	// Check for bad pointers or pointers we can't use.
+	{
+		var bad string
+		p := uintptr(v)
+		if p+size < p {
+			bad = "region exceeds uintptr range"
+		} else if arenaIndex(p) >= 1<<arenaBits {
+			bad = "base outside usable address space"
+		} else if arenaIndex(p+size-1) >= 1<<arenaBits {
+			bad = "end outside usable address space"
+		}
+		if bad != "" {
+			// This should be impossible on most architectures,
+			// but it would be really confusing to debug.
+			print("runtime: memory allocated by OS [", hex(p), ", ", hex(p+size), ") not in usable address space: ", bad, "\n")
+			throw("memory reservation exceeds address space limit")
+		}
+	}
+
+	if uintptr(v)&(heapArenaBytes-1) != 0 {
+		throw("misrounded allocation in sysAlloc")
+	}
+
+mapped:
+	// Create arena metadata.
+	for ri := arenaIndex(uintptr(v)); ri <= arenaIndex(uintptr(v)+size-1); ri++ {
+		l2 := h.arenas[ri.l1()]
+		if l2 == nil {
+			// Allocate an L2 arena map.
+			//
+			// Use sysAllocOS instead of sysAlloc or persistentalloc because there's no
+			// statistic we can comfortably account for this space in. With this structure,
+			// we rely on demand paging to avoid large overheads, but tracking which memory
+			// is paged in is too expensive. Trying to account for the whole region means
+			// that it will appear like an enormous memory overhead in statistics, even though
+			// it is not.
+			l2 = (*[1 << arenaL2Bits]*heapArena)(sysAllocOS(unsafe.Sizeof(*l2)))
+			if l2 == nil {
+				throw("out of memory allocating heap arena map")
+			}
+			atomic.StorepNoWB(unsafe.Pointer(&h.arenas[ri.l1()]), unsafe.Pointer(l2))
+		}
+
+		if l2[ri.l2()] != nil {
+			throw("arena already initialized")
+		}
+		var r *heapArena
+		r = (*heapArena)(h.heapArenaAlloc.alloc(unsafe.Sizeof(*r), goarch.PtrSize, &memstats.gcMiscSys))
+		if r == nil {
+			r = (*heapArena)(persistentalloc(unsafe.Sizeof(*r), goarch.PtrSize, &memstats.gcMiscSys))
+			if r == nil {
+				throw("out of memory allocating heap arena metadata")
+			}
+		}
+
+		// Add the arena to the arenas list.
+		if len(h.allArenas) == cap(h.allArenas) {
+			size := 2 * uintptr(cap(h.allArenas)) * goarch.PtrSize
+			if size == 0 {
+				size = physPageSize
+			}
+			newArray := (*notInHeap)(persistentalloc(size, goarch.PtrSize, &memstats.gcMiscSys))
+			if newArray == nil {
+				throw("out of memory allocating allArenas")
+			}
+			oldSlice := h.allArenas
+			*(*notInHeapSlice)(unsafe.Pointer(&h.allArenas)) = notInHeapSlice{newArray, len(h.allArenas), int(size / goarch.PtrSize)}
+			copy(h.allArenas, oldSlice)
+			// Do not free the old backing array because
+			// there may be concurrent readers. Since we
+			// double the array each time, this can lead
+			// to at most 2x waste.
+		}
+		h.allArenas = h.allArenas[:len(h.allArenas)+1]
+		h.allArenas[len(h.allArenas)-1] = ri
+
+		// Store atomically just in case an object from the
+		// new heap arena becomes visible before the heap lock
+		// is released (which shouldn't happen, but there's
+		// little downside to this).
+		atomic.StorepNoWB(unsafe.Pointer(&l2[ri.l2()]), unsafe.Pointer(r))
+	}
+
+	// Tell the race detector about the new heap memory.
+	if raceenabled {
+		racemapshadow(v, size)
+	}
+
+	return
+}
+
+// sysReserveAligned is like sysReserve, but the returned pointer is
+// aligned to align bytes. It may reserve either n or n+align bytes,
+// so it returns the size that was reserved.
+func sysReserveAligned(v unsafe.Pointer, size, align uintptr) (unsafe.Pointer, uintptr) {
+	// Since the alignment is rather large in uses of this
+	// function, we're not likely to get it by chance, so we ask
+	// for a larger region and remove the parts we don't need.
+	retries := 0
+retry:
+	p := uintptr(sysReserve(v, size+align))
+	switch {
+	case p == 0:
+		return nil, 0
+	case p&(align-1) == 0:
+		// We got lucky and got an aligned region, so we can
+		// use the whole thing.
+		return unsafe.Pointer(p), size + align
+	case GOOS == "windows":
+		// On Windows we can't release pieces of a
+		// reservation, so we release the whole thing and
+		// re-reserve the aligned sub-region. This may race,
+		// so we may have to try again.
+		sysFreeOS(unsafe.Pointer(p), size+align)
+		p = alignUp(p, align)
+		p2 := sysReserve(unsafe.Pointer(p), size)
+		if p != uintptr(p2) {
+			// Must have raced. Try again.
+			sysFreeOS(p2, size)
+			if retries++; retries == 100 {
+				throw("failed to allocate aligned heap memory; too many retries")
+			}
+			goto retry
+		}
+		// Success.
+		return p2, size
+	default:
+		// Trim off the unaligned parts.
+		pAligned := alignUp(p, align)
+		sysFreeOS(unsafe.Pointer(p), pAligned-p)
+		end := pAligned + size
+		endLen := (p + size + align) - end
+		if endLen > 0 {
+			sysFreeOS(unsafe.Pointer(end), endLen)
+		}
+		return unsafe.Pointer(pAligned), size
+	}
+}
+
+// base address for all 0-byte allocations
+var zerobase uintptr
+
+// nextFreeFast returns the next free object if one is quickly available.
+// Otherwise it returns 0.
+func nextFreeFast(s *mspan) gclinkptr {
+	theBit := sys.Ctz64(s.allocCache) // Is there a free object in the allocCache?
+	if theBit < 64 {
+		result := s.freeindex + uintptr(theBit)
+		if result < s.nelems {
+			freeidx := result + 1
+			if freeidx%64 == 0 && freeidx != s.nelems {
+				return 0
+			}
+			s.allocCache >>= uint(theBit + 1)
+			s.freeindex = freeidx
+			s.allocCount++
+			return gclinkptr(result*s.elemsize + s.base())
+		}
+	}
+	return 0
+}
+
+// nextFree returns the next free object from the cached span if one is available.
+// Otherwise it refills the cache with a span with an available object and
+// returns that object along with a flag indicating that this was a heavy
+// weight allocation. If it is a heavy weight allocation the caller must
+// determine whether a new GC cycle needs to be started or if the GC is active
+// whether this goroutine needs to assist the GC.
+//
+// Must run in a non-preemptible context since otherwise the owner of
+// c could change.
+func (c *mcache) nextFree(spc spanClass) (v gclinkptr, s *mspan, shouldhelpgc bool) {
+	s = c.alloc[spc]
+	shouldhelpgc = false
+	freeIndex := s.nextFreeIndex()
+	if freeIndex == s.nelems {
+		// The span is full.
+		if uintptr(s.allocCount) != s.nelems {
+			println("runtime: s.allocCount=", s.allocCount, "s.nelems=", s.nelems)
+			throw("s.allocCount != s.nelems && freeIndex == s.nelems")
+		}
+		c.refill(spc)
+		shouldhelpgc = true
+		s = c.alloc[spc]
+
+		freeIndex = s.nextFreeIndex()
+	}
+
+	if freeIndex >= s.nelems {
+		throw("freeIndex is not valid")
+	}
+
+	v = gclinkptr(freeIndex*s.elemsize + s.base())
+	s.allocCount++
+	if uintptr(s.allocCount) > s.nelems {
+		println("s.allocCount=", s.allocCount, "s.nelems=", s.nelems)
+		throw("s.allocCount > s.nelems")
+	}
+	return
+}
+
+// Allocate an object of size bytes.
+// Small objects are allocated from the per-P cache's free lists.
+// Large objects (> 32 kB) are allocated straight from the heap.
+func mallocgc(size uintptr, typ *_type, needzero bool) unsafe.Pointer {
+	if gcphase == _GCmarktermination {
+		throw("mallocgc called with gcphase == _GCmarktermination")
+	}
+
+	if size == 0 {
+		return unsafe.Pointer(&zerobase)
+	}
+	userSize := size
+	if asanenabled {
+		// Refer to ASAN runtime library, the malloc() function allocates extra memory,
+		// the redzone, around the user requested memory region. And the redzones are marked
+		// as unaddressable. We perform the same operations in Go to detect the overflows or
+		// underflows.
+		size += computeRZlog(size)
+	}
+
+	if debug.malloc {
+		if debug.sbrk != 0 {
+			align := uintptr(16)
+			if typ != nil {
+				// TODO(austin): This should be just
+				//   align = uintptr(typ.align)
+				// but that's only 4 on 32-bit platforms,
+				// even if there's a uint64 field in typ (see #599).
+				// This causes 64-bit atomic accesses to panic.
+				// Hence, we use stricter alignment that matches
+				// the normal allocator better.
+				if size&7 == 0 {
+					align = 8
+				} else if size&3 == 0 {
+					align = 4
+				} else if size&1 == 0 {
+					align = 2
+				} else {
+					align = 1
+				}
+			}
+			return persistentalloc(size, align, &memstats.other_sys)
+		}
+
+		if inittrace.active && inittrace.id == getg().goid {
+			// Init functions are executed sequentially in a single goroutine.
+			inittrace.allocs += 1
+		}
+	}
+
+	// assistG is the G to charge for this allocation, or nil if
+	// GC is not currently active.
+	var assistG *g
+	if gcBlackenEnabled != 0 {
+		// Charge the current user G for this allocation.
+		assistG = getg()
+		if assistG.m.curg != nil {
+			assistG = assistG.m.curg
+		}
+		// Charge the allocation against the G. We'll account
+		// for internal fragmentation at the end of mallocgc.
+		assistG.gcAssistBytes -= int64(size)
+
+		if assistG.gcAssistBytes < 0 {
+			// This G is in debt. Assist the GC to correct
+			// this before allocating. This must happen
+			// before disabling preemption.
+			gcAssistAlloc(assistG)
+		}
+	}
+
+	// Set mp.mallocing to keep from being preempted by GC.
+	mp := acquirem()
+	if mp.mallocing != 0 {
+		throw("malloc deadlock")
+	}
+	if mp.gsignal == getg() {
+		throw("malloc during signal")
+	}
+	mp.mallocing = 1
+
+	shouldhelpgc := false
+	dataSize := userSize
+	c := getMCache(mp)
+	if c == nil {
+		throw("mallocgc called without a P or outside bootstrapping")
+	}
+	var span *mspan
+	var x unsafe.Pointer
+	noscan := typ == nil || typ.ptrdata == 0
+	// In some cases block zeroing can profitably (for latency reduction purposes)
+	// be delayed till preemption is possible; delayedZeroing tracks that state.
+	delayedZeroing := false
+	if size <= maxSmallSize {
+		if noscan && size < maxTinySize {
+			// Tiny allocator.
+			//
+			// Tiny allocator combines several tiny allocation requests
+			// into a single memory block. The resulting memory block
+			// is freed when all subobjects are unreachable. The subobjects
+			// must be noscan (don't have pointers), this ensures that
+			// the amount of potentially wasted memory is bounded.
+			//
+			// Size of the memory block used for combining (maxTinySize) is tunable.
+			// Current setting is 16 bytes, which relates to 2x worst case memory
+			// wastage (when all but one subobjects are unreachable).
+			// 8 bytes would result in no wastage at all, but provides less
+			// opportunities for combining.
+			// 32 bytes provides more opportunities for combining,
+			// but can lead to 4x worst case wastage.
+			// The best case winning is 8x regardless of block size.
+			//
+			// Objects obtained from tiny allocator must not be freed explicitly.
+			// So when an object will be freed explicitly, we ensure that
+			// its size >= maxTinySize.
+			//
+			// SetFinalizer has a special case for objects potentially coming
+			// from tiny allocator, it such case it allows to set finalizers
+			// for an inner byte of a memory block.
+			//
+			// The main targets of tiny allocator are small strings and
+			// standalone escaping variables. On a json benchmark
+			// the allocator reduces number of allocations by ~12% and
+			// reduces heap size by ~20%.
+			off := c.tinyoffset
+			// Align tiny pointer for required (conservative) alignment.
+			if size&7 == 0 {
+				off = alignUp(off, 8)
+			} else if goarch.PtrSize == 4 && size == 12 {
+				// Conservatively align 12-byte objects to 8 bytes on 32-bit
+				// systems so that objects whose first field is a 64-bit
+				// value is aligned to 8 bytes and does not cause a fault on
+				// atomic access. See issue 37262.
+				// TODO(mknyszek): Remove this workaround if/when issue 36606
+				// is resolved.
+				off = alignUp(off, 8)
+			} else if size&3 == 0 {
+				off = alignUp(off, 4)
+			} else if size&1 == 0 {
+				off = alignUp(off, 2)
+			}
+			if off+size <= maxTinySize && c.tiny != 0 {
+				// The object fits into existing tiny block.
+				x = unsafe.Pointer(c.tiny + off)
+				c.tinyoffset = off + size
+				c.tinyAllocs++
+				mp.mallocing = 0
+				releasem(mp)
+				return x
+			}
+			// Allocate a new maxTinySize block.
+			span = c.alloc[tinySpanClass]
+			v := nextFreeFast(span)
+			if v == 0 {
+				v, span, shouldhelpgc = c.nextFree(tinySpanClass)
+			}
+			x = unsafe.Pointer(v)
+			(*[2]uint64)(x)[0] = 0
+			(*[2]uint64)(x)[1] = 0
+			// See if we need to replace the existing tiny block with the new one
+			// based on amount of remaining free space.
+			if !raceenabled && (size < c.tinyoffset || c.tiny == 0) {
+				// Note: disabled when race detector is on, see comment near end of this function.
+				c.tiny = uintptr(x)
+				c.tinyoffset = size
+			}
+			size = maxTinySize
+		} else {
+			var sizeclass uint8
+			if size <= smallSizeMax-8 {
+				sizeclass = size_to_class8[divRoundUp(size, smallSizeDiv)]
+			} else {
+				sizeclass = size_to_class128[divRoundUp(size-smallSizeMax, largeSizeDiv)]
+			}
+			size = uintptr(class_to_size[sizeclass])
+			spc := makeSpanClass(sizeclass, noscan)
+			span = c.alloc[spc]
+			v := nextFreeFast(span)
+			if v == 0 {
+				v, span, shouldhelpgc = c.nextFree(spc)
+			}
+			x = unsafe.Pointer(v)
+			if needzero && span.needzero != 0 {
+				memclrNoHeapPointers(unsafe.Pointer(v), size)
+			}
+		}
+	} else {
+		shouldhelpgc = true
+		// For large allocations, keep track of zeroed state so that
+		// bulk zeroing can be happen later in a preemptible context.
+		span = c.allocLarge(size, noscan)
+		span.freeindex = 1
+		span.allocCount = 1
+		size = span.elemsize
+		x = unsafe.Pointer(span.base())
+		if needzero && span.needzero != 0 {
+			if noscan {
+				delayedZeroing = true
+			} else {
+				memclrNoHeapPointers(x, size)
+				// We've in theory cleared almost the whole span here,
+				// and could take the extra step of actually clearing
+				// the whole thing. However, don't. Any GC bits for the
+				// uncleared parts will be zero, and it's just going to
+				// be needzero = 1 once freed anyway.
+			}
+		}
+	}
+
+	var scanSize uintptr
+	if !noscan {
+		heapBitsSetType(uintptr(x), size, dataSize, typ)
+		if dataSize > typ.size {
+			// Array allocation. If there are any
+			// pointers, GC has to scan to the last
+			// element.
+			if typ.ptrdata != 0 {
+				scanSize = dataSize - typ.size + typ.ptrdata
+			}
+		} else {
+			scanSize = typ.ptrdata
+		}
+		c.scanAlloc += scanSize
+	}
+
+	// Ensure that the stores above that initialize x to
+	// type-safe memory and set the heap bits occur before
+	// the caller can make x observable to the garbage
+	// collector. Otherwise, on weakly ordered machines,
+	// the garbage collector could follow a pointer to x,
+	// but see uninitialized memory or stale heap bits.
+	publicationBarrier()
+
+	// Allocate black during GC.
+	// All slots hold nil so no scanning is needed.
+	// This may be racing with GC so do it atomically if there can be
+	// a race marking the bit.
+	if gcphase != _GCoff {
+		gcmarknewobject(span, uintptr(x), size, scanSize)
+	}
+
+	if raceenabled {
+		racemalloc(x, size)
+	}
+
+	if msanenabled {
+		msanmalloc(x, size)
+	}
+
+	if asanenabled {
+		// We should only read/write the memory with the size asked by the user.
+		// The rest of the allocated memory should be poisoned, so that we can report
+		// errors when accessing poisoned memory.
+		// The allocated memory is larger than required userSize, it will also include
+		// redzone and some other padding bytes.
+		rzBeg := unsafe.Add(x, userSize)
+		asanpoison(rzBeg, size-userSize)
+		asanunpoison(x, userSize)
+	}
+
+	if rate := MemProfileRate; rate > 0 {
+		// Note cache c only valid while m acquired; see #47302
+		if rate != 1 && size < c.nextSample {
+			c.nextSample -= size
+		} else {
+			profilealloc(mp, x, size)
+		}
+	}
+	mp.mallocing = 0
+	releasem(mp)
+
+	// Pointerfree data can be zeroed late in a context where preemption can occur.
+	// x will keep the memory alive.
+	if delayedZeroing {
+		if !noscan {
+			throw("delayed zeroing on data that may contain pointers")
+		}
+		memclrNoHeapPointersChunked(size, x) // This is a possible preemption point: see #47302
+	}
+
+	if debug.malloc {
+		if debug.allocfreetrace != 0 {
+			tracealloc(x, size, typ)
+		}
+
+		if inittrace.active && inittrace.id == getg().goid {
+			// Init functions are executed sequentially in a single goroutine.
+			inittrace.bytes += uint64(size)
+		}
+	}
+
+	if assistG != nil {
+		// Account for internal fragmentation in the assist
+		// debt now that we know it.
+		assistG.gcAssistBytes -= int64(size - dataSize)
+	}
+
+	if shouldhelpgc {
+		if t := (gcTrigger{kind: gcTriggerHeap}); t.test() {
+			gcStart(t)
+		}
+	}
+
+	if raceenabled && noscan && dataSize < maxTinySize {
+		// Pad tinysize allocations so they are aligned with the end
+		// of the tinyalloc region. This ensures that any arithmetic
+		// that goes off the top end of the object will be detectable
+		// by checkptr (issue 38872).
+		// Note that we disable tinyalloc when raceenabled for this to work.
+		// TODO: This padding is only performed when the race detector
+		// is enabled. It would be nice to enable it if any package
+		// was compiled with checkptr, but there's no easy way to
+		// detect that (especially at compile time).
+		// TODO: enable this padding for all allocations, not just
+		// tinyalloc ones. It's tricky because of pointer maps.
+		// Maybe just all noscan objects?
+		x = add(x, size-dataSize)
+	}
+
+	return x
+}
+
+// memclrNoHeapPointersChunked repeatedly calls memclrNoHeapPointers
+// on chunks of the buffer to be zeroed, with opportunities for preemption
+// along the way.  memclrNoHeapPointers contains no safepoints and also
+// cannot be preemptively scheduled, so this provides a still-efficient
+// block copy that can also be preempted on a reasonable granularity.
+//
+// Use this with care; if the data being cleared is tagged to contain
+// pointers, this allows the GC to run before it is all cleared.
+func memclrNoHeapPointersChunked(size uintptr, x unsafe.Pointer) {
+	v := uintptr(x)
+	// got this from benchmarking. 128k is too small, 512k is too large.
+	const chunkBytes = 256 * 1024
+	vsize := v + size
+	for voff := v; voff < vsize; voff = voff + chunkBytes {
+		if getg().preempt {
+			// may hold locks, e.g., profiling
+			goschedguarded()
+		}
+		// clear min(avail, lump) bytes
+		n := vsize - voff
+		if n > chunkBytes {
+			n = chunkBytes
+		}
+		memclrNoHeapPointers(unsafe.Pointer(voff), n)
+	}
+}
+
+// implementation of new builtin
+// compiler (both frontend and SSA backend) knows the signature
+// of this function
+func newobject(typ *_type) unsafe.Pointer {
+	return mallocgc(typ.size, typ, true)
+}
+
+//go:linkname reflect_unsafe_New reflect.unsafe_New
+func reflect_unsafe_New(typ *_type) unsafe.Pointer {
+	return mallocgc(typ.size, typ, true)
+}
+
+//go:linkname reflectlite_unsafe_New internal/reflectlite.unsafe_New
+func reflectlite_unsafe_New(typ *_type) unsafe.Pointer {
+	return mallocgc(typ.size, typ, true)
+}
+
+// newarray allocates an array of n elements of type typ.
+func newarray(typ *_type, n int) unsafe.Pointer {
+	if n == 1 {
+		return mallocgc(typ.size, typ, true)
+	}
+	mem, overflow := math.MulUintptr(typ.size, uintptr(n))
+	if overflow || mem > maxAlloc || n < 0 {
+		panic(plainError("runtime: allocation size out of range"))
+	}
+	return mallocgc(mem, typ, true)
+}
+
+//go:linkname reflect_unsafe_NewArray reflect.unsafe_NewArray
+func reflect_unsafe_NewArray(typ *_type, n int) unsafe.Pointer {
+	return newarray(typ, n)
+}
+
+func profilealloc(mp *m, x unsafe.Pointer, size uintptr) {
+	c := getMCache(mp)
+	if c == nil {
+		throw("profilealloc called without a P or outside bootstrapping")
+	}
+	c.nextSample = nextSample()
+	mProf_Malloc(x, size)
+}
+
+// nextSample returns the next sampling point for heap profiling. The goal is
+// to sample allocations on average every MemProfileRate bytes, but with a
+// completely random distribution over the allocation timeline; this
+// corresponds to a Poisson process with parameter MemProfileRate. In Poisson
+// processes, the distance between two samples follows the exponential
+// distribution (exp(MemProfileRate)), so the best return value is a random
+// number taken from an exponential distribution whose mean is MemProfileRate.
+func nextSample() uintptr {
+	if MemProfileRate == 1 {
+		// Callers assign our return value to
+		// mcache.next_sample, but next_sample is not used
+		// when the rate is 1. So avoid the math below and
+		// just return something.
+		return 0
+	}
+	if GOOS == "plan9" {
+		// Plan 9 doesn't support floating point in note handler.
+		if g := getg(); g == g.m.gsignal {
+			return nextSampleNoFP()
+		}
+	}
+
+	return uintptr(fastexprand(MemProfileRate))
+}
+
+// fastexprand returns a random number from an exponential distribution with
+// the specified mean.
+func fastexprand(mean int) int32 {
+	// Avoid overflow. Maximum possible step is
+	// -ln(1/(1<<randomBitCount)) * mean, approximately 20 * mean.
+	switch {
+	case mean > 0x7000000:
+		mean = 0x7000000
+	case mean == 0:
+		return 0
+	}
+
+	// Take a random sample of the exponential distribution exp(-mean*x).
+	// The probability distribution function is mean*exp(-mean*x), so the CDF is
+	// p = 1 - exp(-mean*x), so
+	// q = 1 - p == exp(-mean*x)
+	// log_e(q) = -mean*x
+	// -log_e(q)/mean = x
+	// x = -log_e(q) * mean
+	// x = log_2(q) * (-log_e(2)) * mean    ; Using log_2 for efficiency
+	const randomBitCount = 26
+	q := fastrandn(1<<randomBitCount) + 1
+	qlog := fastlog2(float64(q)) - randomBitCount
+	if qlog > 0 {
+		qlog = 0
+	}
+	const minusLog2 = -0.6931471805599453 // -ln(2)
+	return int32(qlog*(minusLog2*float64(mean))) + 1
+}
+
+// nextSampleNoFP is similar to nextSample, but uses older,
+// simpler code to avoid floating point.
+func nextSampleNoFP() uintptr {
+	// Set first allocation sample size.
+	rate := MemProfileRate
+	if rate > 0x3fffffff { // make 2*rate not overflow
+		rate = 0x3fffffff
+	}
+	if rate != 0 {
+		return uintptr(fastrandn(uint32(2 * rate)))
+	}
+	return 0
+}
+
+type persistentAlloc struct {
+	base *notInHeap
+	off  uintptr
+}
+
+var globalAlloc struct {
+	mutex
+	persistentAlloc
+}
+
+// persistentChunkSize is the number of bytes we allocate when we grow
+// a persistentAlloc.
+const persistentChunkSize = 256 << 10
+
+// persistentChunks is a list of all the persistent chunks we have
+// allocated. The list is maintained through the first word in the
+// persistent chunk. This is updated atomically.
+var persistentChunks *notInHeap
+
+// Wrapper around sysAlloc that can allocate small chunks.
+// There is no associated free operation.
+// Intended for things like function/type/debug-related persistent data.
+// If align is 0, uses default align (currently 8).
+// The returned memory will be zeroed.
+// sysStat must be non-nil.
+//
+// Consider marking persistentalloc'd types go:notinheap.
+func persistentalloc(size, align uintptr, sysStat *sysMemStat) unsafe.Pointer {
+	var p *notInHeap
+	systemstack(func() {
+		p = persistentalloc1(size, align, sysStat)
+	})
+	return unsafe.Pointer(p)
+}
+
+// Must run on system stack because stack growth can (re)invoke it.
+// See issue 9174.
+//
+//go:systemstack
+func persistentalloc1(size, align uintptr, sysStat *sysMemStat) *notInHeap {
+	const (
+		maxBlock = 64 << 10 // VM reservation granularity is 64K on windows
+	)
+
+	if size == 0 {
+		throw("persistentalloc: size == 0")
+	}
+	if align != 0 {
+		if align&(align-1) != 0 {
+			throw("persistentalloc: align is not a power of 2")
+		}
+		if align > _PageSize {
+			throw("persistentalloc: align is too large")
+		}
+	} else {
+		align = 8
+	}
+
+	if size >= maxBlock {
+		return (*notInHeap)(sysAlloc(size, sysStat))
+	}
+
+	mp := acquirem()
+	var persistent *persistentAlloc
+	if mp != nil && mp.p != 0 {
+		persistent = &mp.p.ptr().palloc
+	} else {
+		lock(&globalAlloc.mutex)
+		persistent = &globalAlloc.persistentAlloc
+	}
+	persistent.off = alignUp(persistent.off, align)
+	if persistent.off+size > persistentChunkSize || persistent.base == nil {
+		persistent.base = (*notInHeap)(sysAlloc(persistentChunkSize, &memstats.other_sys))
+		if persistent.base == nil {
+			if persistent == &globalAlloc.persistentAlloc {
+				unlock(&globalAlloc.mutex)
+			}
+			throw("runtime: cannot allocate memory")
+		}
+
+		// Add the new chunk to the persistentChunks list.
+		for {
+			chunks := uintptr(unsafe.Pointer(persistentChunks))
+			*(*uintptr)(unsafe.Pointer(persistent.base)) = chunks
+			if atomic.Casuintptr((*uintptr)(unsafe.Pointer(&persistentChunks)), chunks, uintptr(unsafe.Pointer(persistent.base))) {
+				break
+			}
+		}
+		persistent.off = alignUp(goarch.PtrSize, align)
+	}
+	p := persistent.base.add(persistent.off)
+	persistent.off += size
+	releasem(mp)
+	if persistent == &globalAlloc.persistentAlloc {
+		unlock(&globalAlloc.mutex)
+	}
+
+	if sysStat != &memstats.other_sys {
+		sysStat.add(int64(size))
+		memstats.other_sys.add(-int64(size))
+	}
+	return p
+}
+
+// inPersistentAlloc reports whether p points to memory allocated by
+// persistentalloc. This must be nosplit because it is called by the
+// cgo checker code, which is called by the write barrier code.
+//
+//go:nosplit
+func inPersistentAlloc(p uintptr) bool {
+	chunk := atomic.Loaduintptr((*uintptr)(unsafe.Pointer(&persistentChunks)))
+	for chunk != 0 {
+		if p >= chunk && p < chunk+persistentChunkSize {
+			return true
+		}
+		chunk = *(*uintptr)(unsafe.Pointer(chunk))
+	}
+	return false
+}
+
+// linearAlloc is a simple linear allocator that pre-reserves a region
+// of memory and then optionally maps that region into the Ready state
+// as needed.
+//
+// The caller is responsible for locking.
+type linearAlloc struct {
+	next   uintptr // next free byte
+	mapped uintptr // one byte past end of mapped space
+	end    uintptr // end of reserved space
+
+	mapMemory bool // transition memory from Reserved to Ready if true
+}
+
+func (l *linearAlloc) init(base, size uintptr, mapMemory bool) {
+	if base+size < base {
+		// Chop off the last byte. The runtime isn't prepared
+		// to deal with situations where the bounds could overflow.
+		// Leave that memory reserved, though, so we don't map it
+		// later.
+		size -= 1
+	}
+	l.next, l.mapped = base, base
+	l.end = base + size
+	l.mapMemory = mapMemory
+}
+
+func (l *linearAlloc) alloc(size, align uintptr, sysStat *sysMemStat) unsafe.Pointer {
+	p := alignUp(l.next, align)
+	if p+size > l.end {
+		return nil
+	}
+	l.next = p + size
+	if pEnd := alignUp(l.next-1, physPageSize); pEnd > l.mapped {
+		if l.mapMemory {
+			// Transition from Reserved to Prepared to Ready.
+			n := pEnd - l.mapped
+			sysMap(unsafe.Pointer(l.mapped), n, sysStat)
+			sysUsed(unsafe.Pointer(l.mapped), n, n)
+		}
+		l.mapped = pEnd
+	}
+	return unsafe.Pointer(p)
+}
+
+// notInHeap is off-heap memory allocated by a lower-level allocator
+// like sysAlloc or persistentAlloc.
+//
+// In general, it's better to use real types marked as go:notinheap,
+// but this serves as a generic type for situations where that isn't
+// possible (like in the allocators).
+//
+// TODO: Use this as the return type of sysAlloc, persistentAlloc, etc?
+//
+//go:notinheap
+type notInHeap struct{}
+
+func (p *notInHeap) add(bytes uintptr) *notInHeap {
+	return (*notInHeap)(unsafe.Pointer(uintptr(unsafe.Pointer(p)) + bytes))
+}
+
+// computeRZlog computes the size of the redzone.
+// Refer to the implementation of the compiler-rt.
+func computeRZlog(userSize uintptr) uintptr {
+	switch {
+	case userSize <= (64 - 16):
+		return 16 << 0
+	case userSize <= (128 - 32):
+		return 16 << 1
+	case userSize <= (512 - 64):
+		return 16 << 2
+	case userSize <= (4096 - 128):
+		return 16 << 3
+	case userSize <= (1<<14)-256:
+		return 16 << 4
+	case userSize <= (1<<15)-512:
+		return 16 << 5
+	case userSize <= (1<<16)-1024:
+		return 16 << 6
+	default:
+		return 16 << 7
+	}
+}
diff --git a/contrib/go/_std_1.19/src/runtime/map.go b/contrib/go/_std_1.19/src/runtime/map.go
new file mode 100644
index 0000000000..65be4727fd
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/map.go
@@ -0,0 +1,1418 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+// This file contains the implementation of Go's map type.
+//
+// A map is just a hash table. The data is arranged
+// into an array of buckets. Each bucket contains up to
+// 8 key/elem pairs. The low-order bits of the hash are
+// used to select a bucket. Each bucket contains a few
+// high-order bits of each hash to distinguish the entries
+// within a single bucket.
+//
+// If more than 8 keys hash to a bucket, we chain on
+// extra buckets.
+//
+// When the hashtable grows, we allocate a new array
+// of buckets twice as big. Buckets are incrementally
+// copied from the old bucket array to the new bucket array.
+//
+// Map iterators walk through the array of buckets and
+// return the keys in walk order (bucket #, then overflow
+// chain order, then bucket index).  To maintain iteration
+// semantics, we never move keys within their bucket (if
+// we did, keys might be returned 0 or 2 times).  When
+// growing the table, iterators remain iterating through the
+// old table and must check the new table if the bucket
+// they are iterating through has been moved ("evacuated")
+// to the new table.
+
+// Picking loadFactor: too large and we have lots of overflow
+// buckets, too small and we waste a lot of space. I wrote
+// a simple program to check some stats for different loads:
+// (64-bit, 8 byte keys and elems)
+//  loadFactor    %overflow  bytes/entry     hitprobe    missprobe
+//        4.00         2.13        20.77         3.00         4.00
+//        4.50         4.05        17.30         3.25         4.50
+//        5.00         6.85        14.77         3.50         5.00
+//        5.50        10.55        12.94         3.75         5.50
+//        6.00        15.27        11.67         4.00         6.00
+//        6.50        20.90        10.79         4.25         6.50
+//        7.00        27.14        10.15         4.50         7.00
+//        7.50        34.03         9.73         4.75         7.50
+//        8.00        41.10         9.40         5.00         8.00
+//
+// %overflow   = percentage of buckets which have an overflow bucket
+// bytes/entry = overhead bytes used per key/elem pair
+// hitprobe    = # of entries to check when looking up a present key
+// missprobe   = # of entries to check when looking up an absent key
+//
+// Keep in mind this data is for maximally loaded tables, i.e. just
+// before the table grows. Typical tables will be somewhat less loaded.
+
+import (
+	"internal/abi"
+	"internal/goarch"
+	"runtime/internal/atomic"
+	"runtime/internal/math"
+	"unsafe"
+)
+
+const (
+	// Maximum number of key/elem pairs a bucket can hold.
+	bucketCntBits = 3
+	bucketCnt     = 1 << bucketCntBits
+
+	// Maximum average load of a bucket that triggers growth is 6.5.
+	// Represent as loadFactorNum/loadFactorDen, to allow integer math.
+	loadFactorNum = 13
+	loadFactorDen = 2
+
+	// Maximum key or elem size to keep inline (instead of mallocing per element).
+	// Must fit in a uint8.
+	// Fast versions cannot handle big elems - the cutoff size for
+	// fast versions in cmd/compile/internal/gc/walk.go must be at most this elem.
+	maxKeySize  = 128
+	maxElemSize = 128
+
+	// data offset should be the size of the bmap struct, but needs to be
+	// aligned correctly. For amd64p32 this means 64-bit alignment
+	// even though pointers are 32 bit.
+	dataOffset = unsafe.Offsetof(struct {
+		b bmap
+		v int64
+	}{}.v)
+
+	// Possible tophash values. We reserve a few possibilities for special marks.
+	// Each bucket (including its overflow buckets, if any) will have either all or none of its
+	// entries in the evacuated* states (except during the evacuate() method, which only happens
+	// during map writes and thus no one else can observe the map during that time).
+	emptyRest      = 0 // this cell is empty, and there are no more non-empty cells at higher indexes or overflows.
+	emptyOne       = 1 // this cell is empty
+	evacuatedX     = 2 // key/elem is valid.  Entry has been evacuated to first half of larger table.
+	evacuatedY     = 3 // same as above, but evacuated to second half of larger table.
+	evacuatedEmpty = 4 // cell is empty, bucket is evacuated.
+	minTopHash     = 5 // minimum tophash for a normal filled cell.
+
+	// flags
+	iterator     = 1 // there may be an iterator using buckets
+	oldIterator  = 2 // there may be an iterator using oldbuckets
+	hashWriting  = 4 // a goroutine is writing to the map
+	sameSizeGrow = 8 // the current map growth is to a new map of the same size
+
+	// sentinel bucket ID for iterator checks
+	noCheck = 1<<(8*goarch.PtrSize) - 1
+)
+
+// isEmpty reports whether the given tophash array entry represents an empty bucket entry.
+func isEmpty(x uint8) bool {
+	return x <= emptyOne
+}
+
+// A header for a Go map.
+type hmap struct {
+	// Note: the format of the hmap is also encoded in cmd/compile/internal/reflectdata/reflect.go.
+	// Make sure this stays in sync with the compiler's definition.
+	count     int // # live cells == size of map.  Must be first (used by len() builtin)
+	flags     uint8
+	B         uint8  // log_2 of # of buckets (can hold up to loadFactor * 2^B items)
+	noverflow uint16 // approximate number of overflow buckets; see incrnoverflow for details
+	hash0     uint32 // hash seed
+
+	buckets    unsafe.Pointer // array of 2^B Buckets. may be nil if count==0.
+	oldbuckets unsafe.Pointer // previous bucket array of half the size, non-nil only when growing
+	nevacuate  uintptr        // progress counter for evacuation (buckets less than this have been evacuated)
+
+	extra *mapextra // optional fields
+}
+
+// mapextra holds fields that are not present on all maps.
+type mapextra struct {
+	// If both key and elem do not contain pointers and are inline, then we mark bucket
+	// type as containing no pointers. This avoids scanning such maps.
+	// However, bmap.overflow is a pointer. In order to keep overflow buckets
+	// alive, we store pointers to all overflow buckets in hmap.extra.overflow and hmap.extra.oldoverflow.
+	// overflow and oldoverflow are only used if key and elem do not contain pointers.
+	// overflow contains overflow buckets for hmap.buckets.
+	// oldoverflow contains overflow buckets for hmap.oldbuckets.
+	// The indirection allows to store a pointer to the slice in hiter.
+	overflow    *[]*bmap
+	oldoverflow *[]*bmap
+
+	// nextOverflow holds a pointer to a free overflow bucket.
+	nextOverflow *bmap
+}
+
+// A bucket for a Go map.
+type bmap struct {
+	// tophash generally contains the top byte of the hash value
+	// for each key in this bucket. If tophash[0] < minTopHash,
+	// tophash[0] is a bucket evacuation state instead.
+	tophash [bucketCnt]uint8
+	// Followed by bucketCnt keys and then bucketCnt elems.
+	// NOTE: packing all the keys together and then all the elems together makes the
+	// code a bit more complicated than alternating key/elem/key/elem/... but it allows
+	// us to eliminate padding which would be needed for, e.g., map[int64]int8.
+	// Followed by an overflow pointer.
+}
+
+// A hash iteration structure.
+// If you modify hiter, also change cmd/compile/internal/reflectdata/reflect.go
+// and reflect/value.go to match the layout of this structure.
+type hiter struct {
+	key         unsafe.Pointer // Must be in first position.  Write nil to indicate iteration end (see cmd/compile/internal/walk/range.go).
+	elem        unsafe.Pointer // Must be in second position (see cmd/compile/internal/walk/range.go).
+	t           *maptype
+	h           *hmap
+	buckets     unsafe.Pointer // bucket ptr at hash_iter initialization time
+	bptr        *bmap          // current bucket
+	overflow    *[]*bmap       // keeps overflow buckets of hmap.buckets alive
+	oldoverflow *[]*bmap       // keeps overflow buckets of hmap.oldbuckets alive
+	startBucket uintptr        // bucket iteration started at
+	offset      uint8          // intra-bucket offset to start from during iteration (should be big enough to hold bucketCnt-1)
+	wrapped     bool           // already wrapped around from end of bucket array to beginning
+	B           uint8
+	i           uint8
+	bucket      uintptr
+	checkBucket uintptr
+}
+
+// bucketShift returns 1<<b, optimized for code generation.
+func bucketShift(b uint8) uintptr {
+	// Masking the shift amount allows overflow checks to be elided.
+	return uintptr(1) << (b & (goarch.PtrSize*8 - 1))
+}
+
+// bucketMask returns 1<<b - 1, optimized for code generation.
+func bucketMask(b uint8) uintptr {
+	return bucketShift(b) - 1
+}
+
+// tophash calculates the tophash value for hash.
+func tophash(hash uintptr) uint8 {
+	top := uint8(hash >> (goarch.PtrSize*8 - 8))
+	if top < minTopHash {
+		top += minTopHash
+	}
+	return top
+}
+
+func evacuated(b *bmap) bool {
+	h := b.tophash[0]
+	return h > emptyOne && h < minTopHash
+}
+
+func (b *bmap) overflow(t *maptype) *bmap {
+	return *(**bmap)(add(unsafe.Pointer(b), uintptr(t.bucketsize)-goarch.PtrSize))
+}
+
+func (b *bmap) setoverflow(t *maptype, ovf *bmap) {
+	*(**bmap)(add(unsafe.Pointer(b), uintptr(t.bucketsize)-goarch.PtrSize)) = ovf
+}
+
+func (b *bmap) keys() unsafe.Pointer {
+	return add(unsafe.Pointer(b), dataOffset)
+}
+
+// incrnoverflow increments h.noverflow.
+// noverflow counts the number of overflow buckets.
+// This is used to trigger same-size map growth.
+// See also tooManyOverflowBuckets.
+// To keep hmap small, noverflow is a uint16.
+// When there are few buckets, noverflow is an exact count.
+// When there are many buckets, noverflow is an approximate count.
+func (h *hmap) incrnoverflow() {
+	// We trigger same-size map growth if there are
+	// as many overflow buckets as buckets.
+	// We need to be able to count to 1<<h.B.
+	if h.B < 16 {
+		h.noverflow++
+		return
+	}
+	// Increment with probability 1/(1<<(h.B-15)).
+	// When we reach 1<<15 - 1, we will have approximately
+	// as many overflow buckets as buckets.
+	mask := uint32(1)<<(h.B-15) - 1
+	// Example: if h.B == 18, then mask == 7,
+	// and fastrand & 7 == 0 with probability 1/8.
+	if fastrand()&mask == 0 {
+		h.noverflow++
+	}
+}
+
+func (h *hmap) newoverflow(t *maptype, b *bmap) *bmap {
+	var ovf *bmap
+	if h.extra != nil && h.extra.nextOverflow != nil {
+		// We have preallocated overflow buckets available.
+		// See makeBucketArray for more details.
+		ovf = h.extra.nextOverflow
+		if ovf.overflow(t) == nil {
+			// We're not at the end of the preallocated overflow buckets. Bump the pointer.
+			h.extra.nextOverflow = (*bmap)(add(unsafe.Pointer(ovf), uintptr(t.bucketsize)))
+		} else {
+			// This is the last preallocated overflow bucket.
+			// Reset the overflow pointer on this bucket,
+			// which was set to a non-nil sentinel value.
+			ovf.setoverflow(t, nil)
+			h.extra.nextOverflow = nil
+		}
+	} else {
+		ovf = (*bmap)(newobject(t.bucket))
+	}
+	h.incrnoverflow()
+	if t.bucket.ptrdata == 0 {
+		h.createOverflow()
+		*h.extra.overflow = append(*h.extra.overflow, ovf)
+	}
+	b.setoverflow(t, ovf)
+	return ovf
+}
+
+func (h *hmap) createOverflow() {
+	if h.extra == nil {
+		h.extra = new(mapextra)
+	}
+	if h.extra.overflow == nil {
+		h.extra.overflow = new([]*bmap)
+	}
+}
+
+func makemap64(t *maptype, hint int64, h *hmap) *hmap {
+	if int64(int(hint)) != hint {
+		hint = 0
+	}
+	return makemap(t, int(hint), h)
+}
+
+// makemap_small implements Go map creation for make(map[k]v) and
+// make(map[k]v, hint) when hint is known to be at most bucketCnt
+// at compile time and the map needs to be allocated on the heap.
+func makemap_small() *hmap {
+	h := new(hmap)
+	h.hash0 = fastrand()
+	return h
+}
+
+// makemap implements Go map creation for make(map[k]v, hint).
+// If the compiler has determined that the map or the first bucket
+// can be created on the stack, h and/or bucket may be non-nil.
+// If h != nil, the map can be created directly in h.
+// If h.buckets != nil, bucket pointed to can be used as the first bucket.
+func makemap(t *maptype, hint int, h *hmap) *hmap {
+	mem, overflow := math.MulUintptr(uintptr(hint), t.bucket.size)
+	if overflow || mem > maxAlloc {
+		hint = 0
+	}
+
+	// initialize Hmap
+	if h == nil {
+		h = new(hmap)
+	}
+	h.hash0 = fastrand()
+
+	// Find the size parameter B which will hold the requested # of elements.
+	// For hint < 0 overLoadFactor returns false since hint < bucketCnt.
+	B := uint8(0)
+	for overLoadFactor(hint, B) {
+		B++
+	}
+	h.B = B
+
+	// allocate initial hash table
+	// if B == 0, the buckets field is allocated lazily later (in mapassign)
+	// If hint is large zeroing this memory could take a while.
+	if h.B != 0 {
+		var nextOverflow *bmap
+		h.buckets, nextOverflow = makeBucketArray(t, h.B, nil)
+		if nextOverflow != nil {
+			h.extra = new(mapextra)
+			h.extra.nextOverflow = nextOverflow
+		}
+	}
+
+	return h
+}
+
+// makeBucketArray initializes a backing array for map buckets.
+// 1<<b is the minimum number of buckets to allocate.
+// dirtyalloc should either be nil or a bucket array previously
+// allocated by makeBucketArray with the same t and b parameters.
+// If dirtyalloc is nil a new backing array will be alloced and
+// otherwise dirtyalloc will be cleared and reused as backing array.
+func makeBucketArray(t *maptype, b uint8, dirtyalloc unsafe.Pointer) (buckets unsafe.Pointer, nextOverflow *bmap) {
+	base := bucketShift(b)
+	nbuckets := base
+	// For small b, overflow buckets are unlikely.
+	// Avoid the overhead of the calculation.
+	if b >= 4 {
+		// Add on the estimated number of overflow buckets
+		// required to insert the median number of elements
+		// used with this value of b.
+		nbuckets += bucketShift(b - 4)
+		sz := t.bucket.size * nbuckets
+		up := roundupsize(sz)
+		if up != sz {
+			nbuckets = up / t.bucket.size
+		}
+	}
+
+	if dirtyalloc == nil {
+		buckets = newarray(t.bucket, int(nbuckets))
+	} else {
+		// dirtyalloc was previously generated by
+		// the above newarray(t.bucket, int(nbuckets))
+		// but may not be empty.
+		buckets = dirtyalloc
+		size := t.bucket.size * nbuckets
+		if t.bucket.ptrdata != 0 {
+			memclrHasPointers(buckets, size)
+		} else {
+			memclrNoHeapPointers(buckets, size)
+		}
+	}
+
+	if base != nbuckets {
+		// We preallocated some overflow buckets.
+		// To keep the overhead of tracking these overflow buckets to a minimum,
+		// we use the convention that if a preallocated overflow bucket's overflow
+		// pointer is nil, then there are more available by bumping the pointer.
+		// We need a safe non-nil pointer for the last overflow bucket; just use buckets.
+		nextOverflow = (*bmap)(add(buckets, base*uintptr(t.bucketsize)))
+		last := (*bmap)(add(buckets, (nbuckets-1)*uintptr(t.bucketsize)))
+		last.setoverflow(t, (*bmap)(buckets))
+	}
+	return buckets, nextOverflow
+}
+
+// mapaccess1 returns a pointer to h[key].  Never returns nil, instead
+// it will return a reference to the zero object for the elem type if
+// the key is not in the map.
+// NOTE: The returned pointer may keep the whole map live, so don't
+// hold onto it for very long.
+func mapaccess1(t *maptype, h *hmap, key unsafe.Pointer) unsafe.Pointer {
+	if raceenabled && h != nil {
+		callerpc := getcallerpc()
+		pc := abi.FuncPCABIInternal(mapaccess1)
+		racereadpc(unsafe.Pointer(h), callerpc, pc)
+		raceReadObjectPC(t.key, key, callerpc, pc)
+	}
+	if msanenabled && h != nil {
+		msanread(key, t.key.size)
+	}
+	if asanenabled && h != nil {
+		asanread(key, t.key.size)
+	}
+	if h == nil || h.count == 0 {
+		if t.hashMightPanic() {
+			t.hasher(key, 0) // see issue 23734
+		}
+		return unsafe.Pointer(&zeroVal[0])
+	}
+	if h.flags&hashWriting != 0 {
+		fatal("concurrent map read and map write")
+	}
+	hash := t.hasher(key, uintptr(h.hash0))
+	m := bucketMask(h.B)
+	b := (*bmap)(add(h.buckets, (hash&m)*uintptr(t.bucketsize)))
+	if c := h.oldbuckets; c != nil {
+		if !h.sameSizeGrow() {
+			// There used to be half as many buckets; mask down one more power of two.
+			m >>= 1
+		}
+		oldb := (*bmap)(add(c, (hash&m)*uintptr(t.bucketsize)))
+		if !evacuated(oldb) {
+			b = oldb
+		}
+	}
+	top := tophash(hash)
+bucketloop:
+	for ; b != nil; b = b.overflow(t) {
+		for i := uintptr(0); i < bucketCnt; i++ {
+			if b.tophash[i] != top {
+				if b.tophash[i] == emptyRest {
+					break bucketloop
+				}
+				continue
+			}
+			k := add(unsafe.Pointer(b), dataOffset+i*uintptr(t.keysize))
+			if t.indirectkey() {
+				k = *((*unsafe.Pointer)(k))
+			}
+			if t.key.equal(key, k) {
+				e := add(unsafe.Pointer(b), dataOffset+bucketCnt*uintptr(t.keysize)+i*uintptr(t.elemsize))
+				if t.indirectelem() {
+					e = *((*unsafe.Pointer)(e))
+				}
+				return e
+			}
+		}
+	}
+	return unsafe.Pointer(&zeroVal[0])
+}
+
+func mapaccess2(t *maptype, h *hmap, key unsafe.Pointer) (unsafe.Pointer, bool) {
+	if raceenabled && h != nil {
+		callerpc := getcallerpc()
+		pc := abi.FuncPCABIInternal(mapaccess2)
+		racereadpc(unsafe.Pointer(h), callerpc, pc)
+		raceReadObjectPC(t.key, key, callerpc, pc)
+	}
+	if msanenabled && h != nil {
+		msanread(key, t.key.size)
+	}
+	if asanenabled && h != nil {
+		asanread(key, t.key.size)
+	}
+	if h == nil || h.count == 0 {
+		if t.hashMightPanic() {
+			t.hasher(key, 0) // see issue 23734
+		}
+		return unsafe.Pointer(&zeroVal[0]), false
+	}
+	if h.flags&hashWriting != 0 {
+		fatal("concurrent map read and map write")
+	}
+	hash := t.hasher(key, uintptr(h.hash0))
+	m := bucketMask(h.B)
+	b := (*bmap)(add(h.buckets, (hash&m)*uintptr(t.bucketsize)))
+	if c := h.oldbuckets; c != nil {
+		if !h.sameSizeGrow() {
+			// There used to be half as many buckets; mask down one more power of two.
+			m >>= 1
+		}
+		oldb := (*bmap)(add(c, (hash&m)*uintptr(t.bucketsize)))
+		if !evacuated(oldb) {
+			b = oldb
+		}
+	}
+	top := tophash(hash)
+bucketloop:
+	for ; b != nil; b = b.overflow(t) {
+		for i := uintptr(0); i < bucketCnt; i++ {
+			if b.tophash[i] != top {
+				if b.tophash[i] == emptyRest {
+					break bucketloop
+				}
+				continue
+			}
+			k := add(unsafe.Pointer(b), dataOffset+i*uintptr(t.keysize))
+			if t.indirectkey() {
+				k = *((*unsafe.Pointer)(k))
+			}
+			if t.key.equal(key, k) {
+				e := add(unsafe.Pointer(b), dataOffset+bucketCnt*uintptr(t.keysize)+i*uintptr(t.elemsize))
+				if t.indirectelem() {
+					e = *((*unsafe.Pointer)(e))
+				}
+				return e, true
+			}
+		}
+	}
+	return unsafe.Pointer(&zeroVal[0]), false
+}
+
+// returns both key and elem. Used by map iterator
+func mapaccessK(t *maptype, h *hmap, key unsafe.Pointer) (unsafe.Pointer, unsafe.Pointer) {
+	if h == nil || h.count == 0 {
+		return nil, nil
+	}
+	hash := t.hasher(key, uintptr(h.hash0))
+	m := bucketMask(h.B)
+	b := (*bmap)(add(h.buckets, (hash&m)*uintptr(t.bucketsize)))
+	if c := h.oldbuckets; c != nil {
+		if !h.sameSizeGrow() {
+			// There used to be half as many buckets; mask down one more power of two.
+			m >>= 1
+		}
+		oldb := (*bmap)(add(c, (hash&m)*uintptr(t.bucketsize)))
+		if !evacuated(oldb) {
+			b = oldb
+		}
+	}
+	top := tophash(hash)
+bucketloop:
+	for ; b != nil; b = b.overflow(t) {
+		for i := uintptr(0); i < bucketCnt; i++ {
+			if b.tophash[i] != top {
+				if b.tophash[i] == emptyRest {
+					break bucketloop
+				}
+				continue
+			}
+			k := add(unsafe.Pointer(b), dataOffset+i*uintptr(t.keysize))
+			if t.indirectkey() {
+				k = *((*unsafe.Pointer)(k))
+			}
+			if t.key.equal(key, k) {
+				e := add(unsafe.Pointer(b), dataOffset+bucketCnt*uintptr(t.keysize)+i*uintptr(t.elemsize))
+				if t.indirectelem() {
+					e = *((*unsafe.Pointer)(e))
+				}
+				return k, e
+			}
+		}
+	}
+	return nil, nil
+}
+
+func mapaccess1_fat(t *maptype, h *hmap, key, zero unsafe.Pointer) unsafe.Pointer {
+	e := mapaccess1(t, h, key)
+	if e == unsafe.Pointer(&zeroVal[0]) {
+		return zero
+	}
+	return e
+}
+
+func mapaccess2_fat(t *maptype, h *hmap, key, zero unsafe.Pointer) (unsafe.Pointer, bool) {
+	e := mapaccess1(t, h, key)
+	if e == unsafe.Pointer(&zeroVal[0]) {
+		return zero, false
+	}
+	return e, true
+}
+
+// Like mapaccess, but allocates a slot for the key if it is not present in the map.
+func mapassign(t *maptype, h *hmap, key unsafe.Pointer) unsafe.Pointer {
+	if h == nil {
+		panic(plainError("assignment to entry in nil map"))
+	}
+	if raceenabled {
+		callerpc := getcallerpc()
+		pc := abi.FuncPCABIInternal(mapassign)
+		racewritepc(unsafe.Pointer(h), callerpc, pc)
+		raceReadObjectPC(t.key, key, callerpc, pc)
+	}
+	if msanenabled {
+		msanread(key, t.key.size)
+	}
+	if asanenabled {
+		asanread(key, t.key.size)
+	}
+	if h.flags&hashWriting != 0 {
+		fatal("concurrent map writes")
+	}
+	hash := t.hasher(key, uintptr(h.hash0))
+
+	// Set hashWriting after calling t.hasher, since t.hasher may panic,
+	// in which case we have not actually done a write.
+	h.flags ^= hashWriting
+
+	if h.buckets == nil {
+		h.buckets = newobject(t.bucket) // newarray(t.bucket, 1)
+	}
+
+again:
+	bucket := hash & bucketMask(h.B)
+	if h.growing() {
+		growWork(t, h, bucket)
+	}
+	b := (*bmap)(add(h.buckets, bucket*uintptr(t.bucketsize)))
+	top := tophash(hash)
+
+	var inserti *uint8
+	var insertk unsafe.Pointer
+	var elem unsafe.Pointer
+bucketloop:
+	for {
+		for i := uintptr(0); i < bucketCnt; i++ {
+			if b.tophash[i] != top {
+				if isEmpty(b.tophash[i]) && inserti == nil {
+					inserti = &b.tophash[i]
+					insertk = add(unsafe.Pointer(b), dataOffset+i*uintptr(t.keysize))
+					elem = add(unsafe.Pointer(b), dataOffset+bucketCnt*uintptr(t.keysize)+i*uintptr(t.elemsize))
+				}
+				if b.tophash[i] == emptyRest {
+					break bucketloop
+				}
+				continue
+			}
+			k := add(unsafe.Pointer(b), dataOffset+i*uintptr(t.keysize))
+			if t.indirectkey() {
+				k = *((*unsafe.Pointer)(k))
+			}
+			if !t.key.equal(key, k) {
+				continue
+			}
+			// already have a mapping for key. Update it.
+			if t.needkeyupdate() {
+				typedmemmove(t.key, k, key)
+			}
+			elem = add(unsafe.Pointer(b), dataOffset+bucketCnt*uintptr(t.keysize)+i*uintptr(t.elemsize))
+			goto done
+		}
+		ovf := b.overflow(t)
+		if ovf == nil {
+			break
+		}
+		b = ovf
+	}
+
+	// Did not find mapping for key. Allocate new cell & add entry.
+
+	// If we hit the max load factor or we have too many overflow buckets,
+	// and we're not already in the middle of growing, start growing.
+	if !h.growing() && (overLoadFactor(h.count+1, h.B) || tooManyOverflowBuckets(h.noverflow, h.B)) {
+		hashGrow(t, h)
+		goto again // Growing the table invalidates everything, so try again
+	}
+
+	if inserti == nil {
+		// The current bucket and all the overflow buckets connected to it are full, allocate a new one.
+		newb := h.newoverflow(t, b)
+		inserti = &newb.tophash[0]
+		insertk = add(unsafe.Pointer(newb), dataOffset)
+		elem = add(insertk, bucketCnt*uintptr(t.keysize))
+	}
+
+	// store new key/elem at insert position
+	if t.indirectkey() {
+		kmem := newobject(t.key)
+		*(*unsafe.Pointer)(insertk) = kmem
+		insertk = kmem
+	}
+	if t.indirectelem() {
+		vmem := newobject(t.elem)
+		*(*unsafe.Pointer)(elem) = vmem
+	}
+	typedmemmove(t.key, insertk, key)
+	*inserti = top
+	h.count++
+
+done:
+	if h.flags&hashWriting == 0 {
+		fatal("concurrent map writes")
+	}
+	h.flags &^= hashWriting
+	if t.indirectelem() {
+		elem = *((*unsafe.Pointer)(elem))
+	}
+	return elem
+}
+
+func mapdelete(t *maptype, h *hmap, key unsafe.Pointer) {
+	if raceenabled && h != nil {
+		callerpc := getcallerpc()
+		pc := abi.FuncPCABIInternal(mapdelete)
+		racewritepc(unsafe.Pointer(h), callerpc, pc)
+		raceReadObjectPC(t.key, key, callerpc, pc)
+	}
+	if msanenabled && h != nil {
+		msanread(key, t.key.size)
+	}
+	if asanenabled && h != nil {
+		asanread(key, t.key.size)
+	}
+	if h == nil || h.count == 0 {
+		if t.hashMightPanic() {
+			t.hasher(key, 0) // see issue 23734
+		}
+		return
+	}
+	if h.flags&hashWriting != 0 {
+		fatal("concurrent map writes")
+	}
+
+	hash := t.hasher(key, uintptr(h.hash0))
+
+	// Set hashWriting after calling t.hasher, since t.hasher may panic,
+	// in which case we have not actually done a write (delete).
+	h.flags ^= hashWriting
+
+	bucket := hash & bucketMask(h.B)
+	if h.growing() {
+		growWork(t, h, bucket)
+	}
+	b := (*bmap)(add(h.buckets, bucket*uintptr(t.bucketsize)))
+	bOrig := b
+	top := tophash(hash)
+search:
+	for ; b != nil; b = b.overflow(t) {
+		for i := uintptr(0); i < bucketCnt; i++ {
+			if b.tophash[i] != top {
+				if b.tophash[i] == emptyRest {
+					break search
+				}
+				continue
+			}
+			k := add(unsafe.Pointer(b), dataOffset+i*uintptr(t.keysize))
+			k2 := k
+			if t.indirectkey() {
+				k2 = *((*unsafe.Pointer)(k2))
+			}
+			if !t.key.equal(key, k2) {
+				continue
+			}
+			// Only clear key if there are pointers in it.
+			if t.indirectkey() {
+				*(*unsafe.Pointer)(k) = nil
+			} else if t.key.ptrdata != 0 {
+				memclrHasPointers(k, t.key.size)
+			}
+			e := add(unsafe.Pointer(b), dataOffset+bucketCnt*uintptr(t.keysize)+i*uintptr(t.elemsize))
+			if t.indirectelem() {
+				*(*unsafe.Pointer)(e) = nil
+			} else if t.elem.ptrdata != 0 {
+				memclrHasPointers(e, t.elem.size)
+			} else {
+				memclrNoHeapPointers(e, t.elem.size)
+			}
+			b.tophash[i] = emptyOne
+			// If the bucket now ends in a bunch of emptyOne states,
+			// change those to emptyRest states.
+			// It would be nice to make this a separate function, but
+			// for loops are not currently inlineable.
+			if i == bucketCnt-1 {
+				if b.overflow(t) != nil && b.overflow(t).tophash[0] != emptyRest {
+					goto notLast
+				}
+			} else {
+				if b.tophash[i+1] != emptyRest {
+					goto notLast
+				}
+			}
+			for {
+				b.tophash[i] = emptyRest
+				if i == 0 {
+					if b == bOrig {
+						break // beginning of initial bucket, we're done.
+					}
+					// Find previous bucket, continue at its last entry.
+					c := b
+					for b = bOrig; b.overflow(t) != c; b = b.overflow(t) {
+					}
+					i = bucketCnt - 1
+				} else {
+					i--
+				}
+				if b.tophash[i] != emptyOne {
+					break
+				}
+			}
+		notLast:
+			h.count--
+			// Reset the hash seed to make it more difficult for attackers to
+			// repeatedly trigger hash collisions. See issue 25237.
+			if h.count == 0 {
+				h.hash0 = fastrand()
+			}
+			break search
+		}
+	}
+
+	if h.flags&hashWriting == 0 {
+		fatal("concurrent map writes")
+	}
+	h.flags &^= hashWriting
+}
+
+// mapiterinit initializes the hiter struct used for ranging over maps.
+// The hiter struct pointed to by 'it' is allocated on the stack
+// by the compilers order pass or on the heap by reflect_mapiterinit.
+// Both need to have zeroed hiter since the struct contains pointers.
+func mapiterinit(t *maptype, h *hmap, it *hiter) {
+	if raceenabled && h != nil {
+		callerpc := getcallerpc()
+		racereadpc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapiterinit))
+	}
+
+	it.t = t
+	if h == nil || h.count == 0 {
+		return
+	}
+
+	if unsafe.Sizeof(hiter{})/goarch.PtrSize != 12 {
+		throw("hash_iter size incorrect") // see cmd/compile/internal/reflectdata/reflect.go
+	}
+	it.h = h
+
+	// grab snapshot of bucket state
+	it.B = h.B
+	it.buckets = h.buckets
+	if t.bucket.ptrdata == 0 {
+		// Allocate the current slice and remember pointers to both current and old.
+		// This preserves all relevant overflow buckets alive even if
+		// the table grows and/or overflow buckets are added to the table
+		// while we are iterating.
+		h.createOverflow()
+		it.overflow = h.extra.overflow
+		it.oldoverflow = h.extra.oldoverflow
+	}
+
+	// decide where to start
+	var r uintptr
+	if h.B > 31-bucketCntBits {
+		r = uintptr(fastrand64())
+	} else {
+		r = uintptr(fastrand())
+	}
+	it.startBucket = r & bucketMask(h.B)
+	it.offset = uint8(r >> h.B & (bucketCnt - 1))
+
+	// iterator state
+	it.bucket = it.startBucket
+
+	// Remember we have an iterator.
+	// Can run concurrently with another mapiterinit().
+	if old := h.flags; old&(iterator|oldIterator) != iterator|oldIterator {
+		atomic.Or8(&h.flags, iterator|oldIterator)
+	}
+
+	mapiternext(it)
+}
+
+func mapiternext(it *hiter) {
+	h := it.h
+	if raceenabled {
+		callerpc := getcallerpc()
+		racereadpc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapiternext))
+	}
+	if h.flags&hashWriting != 0 {
+		fatal("concurrent map iteration and map write")
+	}
+	t := it.t
+	bucket := it.bucket
+	b := it.bptr
+	i := it.i
+	checkBucket := it.checkBucket
+
+next:
+	if b == nil {
+		if bucket == it.startBucket && it.wrapped {
+			// end of iteration
+			it.key = nil
+			it.elem = nil
+			return
+		}
+		if h.growing() && it.B == h.B {
+			// Iterator was started in the middle of a grow, and the grow isn't done yet.
+			// If the bucket we're looking at hasn't been filled in yet (i.e. the old
+			// bucket hasn't been evacuated) then we need to iterate through the old
+			// bucket and only return the ones that will be migrated to this bucket.
+			oldbucket := bucket & it.h.oldbucketmask()
+			b = (*bmap)(add(h.oldbuckets, oldbucket*uintptr(t.bucketsize)))
+			if !evacuated(b) {
+				checkBucket = bucket
+			} else {
+				b = (*bmap)(add(it.buckets, bucket*uintptr(t.bucketsize)))
+				checkBucket = noCheck
+			}
+		} else {
+			b = (*bmap)(add(it.buckets, bucket*uintptr(t.bucketsize)))
+			checkBucket = noCheck
+		}
+		bucket++
+		if bucket == bucketShift(it.B) {
+			bucket = 0
+			it.wrapped = true
+		}
+		i = 0
+	}
+	for ; i < bucketCnt; i++ {
+		offi := (i + it.offset) & (bucketCnt - 1)
+		if isEmpty(b.tophash[offi]) || b.tophash[offi] == evacuatedEmpty {
+			// TODO: emptyRest is hard to use here, as we start iterating
+			// in the middle of a bucket. It's feasible, just tricky.
+			continue
+		}
+		k := add(unsafe.Pointer(b), dataOffset+uintptr(offi)*uintptr(t.keysize))
+		if t.indirectkey() {
+			k = *((*unsafe.Pointer)(k))
+		}
+		e := add(unsafe.Pointer(b), dataOffset+bucketCnt*uintptr(t.keysize)+uintptr(offi)*uintptr(t.elemsize))
+		if checkBucket != noCheck && !h.sameSizeGrow() {
+			// Special case: iterator was started during a grow to a larger size
+			// and the grow is not done yet. We're working on a bucket whose
+			// oldbucket has not been evacuated yet. Or at least, it wasn't
+			// evacuated when we started the bucket. So we're iterating
+			// through the oldbucket, skipping any keys that will go
+			// to the other new bucket (each oldbucket expands to two
+			// buckets during a grow).
+			if t.reflexivekey() || t.key.equal(k, k) {
+				// If the item in the oldbucket is not destined for
+				// the current new bucket in the iteration, skip it.
+				hash := t.hasher(k, uintptr(h.hash0))
+				if hash&bucketMask(it.B) != checkBucket {
+					continue
+				}
+			} else {
+				// Hash isn't repeatable if k != k (NaNs).  We need a
+				// repeatable and randomish choice of which direction
+				// to send NaNs during evacuation. We'll use the low
+				// bit of tophash to decide which way NaNs go.
+				// NOTE: this case is why we need two evacuate tophash
+				// values, evacuatedX and evacuatedY, that differ in
+				// their low bit.
+				if checkBucket>>(it.B-1) != uintptr(b.tophash[offi]&1) {
+					continue
+				}
+			}
+		}
+		if (b.tophash[offi] != evacuatedX && b.tophash[offi] != evacuatedY) ||
+			!(t.reflexivekey() || t.key.equal(k, k)) {
+			// This is the golden data, we can return it.
+			// OR
+			// key!=key, so the entry can't be deleted or updated, so we can just return it.
+			// That's lucky for us because when key!=key we can't look it up successfully.
+			it.key = k
+			if t.indirectelem() {
+				e = *((*unsafe.Pointer)(e))
+			}
+			it.elem = e
+		} else {
+			// The hash table has grown since the iterator was started.
+			// The golden data for this key is now somewhere else.
+			// Check the current hash table for the data.
+			// This code handles the case where the key
+			// has been deleted, updated, or deleted and reinserted.
+			// NOTE: we need to regrab the key as it has potentially been
+			// updated to an equal() but not identical key (e.g. +0.0 vs -0.0).
+			rk, re := mapaccessK(t, h, k)
+			if rk == nil {
+				continue // key has been deleted
+			}
+			it.key = rk
+			it.elem = re
+		}
+		it.bucket = bucket
+		if it.bptr != b { // avoid unnecessary write barrier; see issue 14921
+			it.bptr = b
+		}
+		it.i = i + 1
+		it.checkBucket = checkBucket
+		return
+	}
+	b = b.overflow(t)
+	i = 0
+	goto next
+}
+
+// mapclear deletes all keys from a map.
+func mapclear(t *maptype, h *hmap) {
+	if raceenabled && h != nil {
+		callerpc := getcallerpc()
+		pc := abi.FuncPCABIInternal(mapclear)
+		racewritepc(unsafe.Pointer(h), callerpc, pc)
+	}
+
+	if h == nil || h.count == 0 {
+		return
+	}
+
+	if h.flags&hashWriting != 0 {
+		fatal("concurrent map writes")
+	}
+
+	h.flags ^= hashWriting
+
+	h.flags &^= sameSizeGrow
+	h.oldbuckets = nil
+	h.nevacuate = 0
+	h.noverflow = 0
+	h.count = 0
+
+	// Reset the hash seed to make it more difficult for attackers to
+	// repeatedly trigger hash collisions. See issue 25237.
+	h.hash0 = fastrand()
+
+	// Keep the mapextra allocation but clear any extra information.
+	if h.extra != nil {
+		*h.extra = mapextra{}
+	}
+
+	// makeBucketArray clears the memory pointed to by h.buckets
+	// and recovers any overflow buckets by generating them
+	// as if h.buckets was newly alloced.
+	_, nextOverflow := makeBucketArray(t, h.B, h.buckets)
+	if nextOverflow != nil {
+		// If overflow buckets are created then h.extra
+		// will have been allocated during initial bucket creation.
+		h.extra.nextOverflow = nextOverflow
+	}
+
+	if h.flags&hashWriting == 0 {
+		fatal("concurrent map writes")
+	}
+	h.flags &^= hashWriting
+}
+
+func hashGrow(t *maptype, h *hmap) {
+	// If we've hit the load factor, get bigger.
+	// Otherwise, there are too many overflow buckets,
+	// so keep the same number of buckets and "grow" laterally.
+	bigger := uint8(1)
+	if !overLoadFactor(h.count+1, h.B) {
+		bigger = 0
+		h.flags |= sameSizeGrow
+	}
+	oldbuckets := h.buckets
+	newbuckets, nextOverflow := makeBucketArray(t, h.B+bigger, nil)
+
+	flags := h.flags &^ (iterator | oldIterator)
+	if h.flags&iterator != 0 {
+		flags |= oldIterator
+	}
+	// commit the grow (atomic wrt gc)
+	h.B += bigger
+	h.flags = flags
+	h.oldbuckets = oldbuckets
+	h.buckets = newbuckets
+	h.nevacuate = 0
+	h.noverflow = 0
+
+	if h.extra != nil && h.extra.overflow != nil {
+		// Promote current overflow buckets to the old generation.
+		if h.extra.oldoverflow != nil {
+			throw("oldoverflow is not nil")
+		}
+		h.extra.oldoverflow = h.extra.overflow
+		h.extra.overflow = nil
+	}
+	if nextOverflow != nil {
+		if h.extra == nil {
+			h.extra = new(mapextra)
+		}
+		h.extra.nextOverflow = nextOverflow
+	}
+
+	// the actual copying of the hash table data is done incrementally
+	// by growWork() and evacuate().
+}
+
+// overLoadFactor reports whether count items placed in 1<<B buckets is over loadFactor.
+func overLoadFactor(count int, B uint8) bool {
+	return count > bucketCnt && uintptr(count) > loadFactorNum*(bucketShift(B)/loadFactorDen)
+}
+
+// tooManyOverflowBuckets reports whether noverflow buckets is too many for a map with 1<<B buckets.
+// Note that most of these overflow buckets must be in sparse use;
+// if use was dense, then we'd have already triggered regular map growth.
+func tooManyOverflowBuckets(noverflow uint16, B uint8) bool {
+	// If the threshold is too low, we do extraneous work.
+	// If the threshold is too high, maps that grow and shrink can hold on to lots of unused memory.
+	// "too many" means (approximately) as many overflow buckets as regular buckets.
+	// See incrnoverflow for more details.
+	if B > 15 {
+		B = 15
+	}
+	// The compiler doesn't see here that B < 16; mask B to generate shorter shift code.
+	return noverflow >= uint16(1)<<(B&15)
+}
+
+// growing reports whether h is growing. The growth may be to the same size or bigger.
+func (h *hmap) growing() bool {
+	return h.oldbuckets != nil
+}
+
+// sameSizeGrow reports whether the current growth is to a map of the same size.
+func (h *hmap) sameSizeGrow() bool {
+	return h.flags&sameSizeGrow != 0
+}
+
+// noldbuckets calculates the number of buckets prior to the current map growth.
+func (h *hmap) noldbuckets() uintptr {
+	oldB := h.B
+	if !h.sameSizeGrow() {
+		oldB--
+	}
+	return bucketShift(oldB)
+}
+
+// oldbucketmask provides a mask that can be applied to calculate n % noldbuckets().
+func (h *hmap) oldbucketmask() uintptr {
+	return h.noldbuckets() - 1
+}
+
+func growWork(t *maptype, h *hmap, bucket uintptr) {
+	// make sure we evacuate the oldbucket corresponding
+	// to the bucket we're about to use
+	evacuate(t, h, bucket&h.oldbucketmask())
+
+	// evacuate one more oldbucket to make progress on growing
+	if h.growing() {
+		evacuate(t, h, h.nevacuate)
+	}
+}
+
+func bucketEvacuated(t *maptype, h *hmap, bucket uintptr) bool {
+	b := (*bmap)(add(h.oldbuckets, bucket*uintptr(t.bucketsize)))
+	return evacuated(b)
+}
+
+// evacDst is an evacuation destination.
+type evacDst struct {
+	b *bmap          // current destination bucket
+	i int            // key/elem index into b
+	k unsafe.Pointer // pointer to current key storage
+	e unsafe.Pointer // pointer to current elem storage
+}
+
+func evacuate(t *maptype, h *hmap, oldbucket uintptr) {
+	b := (*bmap)(add(h.oldbuckets, oldbucket*uintptr(t.bucketsize)))
+	newbit := h.noldbuckets()
+	if !evacuated(b) {
+		// TODO: reuse overflow buckets instead of using new ones, if there
+		// is no iterator using the old buckets.  (If !oldIterator.)
+
+		// xy contains the x and y (low and high) evacuation destinations.
+		var xy [2]evacDst
+		x := &xy[0]
+		x.b = (*bmap)(add(h.buckets, oldbucket*uintptr(t.bucketsize)))
+		x.k = add(unsafe.Pointer(x.b), dataOffset)
+		x.e = add(x.k, bucketCnt*uintptr(t.keysize))
+
+		if !h.sameSizeGrow() {
+			// Only calculate y pointers if we're growing bigger.
+			// Otherwise GC can see bad pointers.
+			y := &xy[1]
+			y.b = (*bmap)(add(h.buckets, (oldbucket+newbit)*uintptr(t.bucketsize)))
+			y.k = add(unsafe.Pointer(y.b), dataOffset)
+			y.e = add(y.k, bucketCnt*uintptr(t.keysize))
+		}
+
+		for ; b != nil; b = b.overflow(t) {
+			k := add(unsafe.Pointer(b), dataOffset)
+			e := add(k, bucketCnt*uintptr(t.keysize))
+			for i := 0; i < bucketCnt; i, k, e = i+1, add(k, uintptr(t.keysize)), add(e, uintptr(t.elemsize)) {
+				top := b.tophash[i]
+				if isEmpty(top) {
+					b.tophash[i] = evacuatedEmpty
+					continue
+				}
+				if top < minTopHash {
+					throw("bad map state")
+				}
+				k2 := k
+				if t.indirectkey() {
+					k2 = *((*unsafe.Pointer)(k2))
+				}
+				var useY uint8
+				if !h.sameSizeGrow() {
+					// Compute hash to make our evacuation decision (whether we need
+					// to send this key/elem to bucket x or bucket y).
+					hash := t.hasher(k2, uintptr(h.hash0))
+					if h.flags&iterator != 0 && !t.reflexivekey() && !t.key.equal(k2, k2) {
+						// If key != key (NaNs), then the hash could be (and probably
+						// will be) entirely different from the old hash. Moreover,
+						// it isn't reproducible. Reproducibility is required in the
+						// presence of iterators, as our evacuation decision must
+						// match whatever decision the iterator made.
+						// Fortunately, we have the freedom to send these keys either
+						// way. Also, tophash is meaningless for these kinds of keys.
+						// We let the low bit of tophash drive the evacuation decision.
+						// We recompute a new random tophash for the next level so
+						// these keys will get evenly distributed across all buckets
+						// after multiple grows.
+						useY = top & 1
+						top = tophash(hash)
+					} else {
+						if hash&newbit != 0 {
+							useY = 1
+						}
+					}
+				}
+
+				if evacuatedX+1 != evacuatedY || evacuatedX^1 != evacuatedY {
+					throw("bad evacuatedN")
+				}
+
+				b.tophash[i] = evacuatedX + useY // evacuatedX + 1 == evacuatedY
+				dst := &xy[useY]                 // evacuation destination
+
+				if dst.i == bucketCnt {
+					dst.b = h.newoverflow(t, dst.b)
+					dst.i = 0
+					dst.k = add(unsafe.Pointer(dst.b), dataOffset)
+					dst.e = add(dst.k, bucketCnt*uintptr(t.keysize))
+				}
+				dst.b.tophash[dst.i&(bucketCnt-1)] = top // mask dst.i as an optimization, to avoid a bounds check
+				if t.indirectkey() {
+					*(*unsafe.Pointer)(dst.k) = k2 // copy pointer
+				} else {
+					typedmemmove(t.key, dst.k, k) // copy elem
+				}
+				if t.indirectelem() {
+					*(*unsafe.Pointer)(dst.e) = *(*unsafe.Pointer)(e)
+				} else {
+					typedmemmove(t.elem, dst.e, e)
+				}
+				dst.i++
+				// These updates might push these pointers past the end of the
+				// key or elem arrays.  That's ok, as we have the overflow pointer
+				// at the end of the bucket to protect against pointing past the
+				// end of the bucket.
+				dst.k = add(dst.k, uintptr(t.keysize))
+				dst.e = add(dst.e, uintptr(t.elemsize))
+			}
+		}
+		// Unlink the overflow buckets & clear key/elem to help GC.
+		if h.flags&oldIterator == 0 && t.bucket.ptrdata != 0 {
+			b := add(h.oldbuckets, oldbucket*uintptr(t.bucketsize))
+			// Preserve b.tophash because the evacuation
+			// state is maintained there.
+			ptr := add(b, dataOffset)
+			n := uintptr(t.bucketsize) - dataOffset
+			memclrHasPointers(ptr, n)
+		}
+	}
+
+	if oldbucket == h.nevacuate {
+		advanceEvacuationMark(h, t, newbit)
+	}
+}
+
+func advanceEvacuationMark(h *hmap, t *maptype, newbit uintptr) {
+	h.nevacuate++
+	// Experiments suggest that 1024 is overkill by at least an order of magnitude.
+	// Put it in there as a safeguard anyway, to ensure O(1) behavior.
+	stop := h.nevacuate + 1024
+	if stop > newbit {
+		stop = newbit
+	}
+	for h.nevacuate != stop && bucketEvacuated(t, h, h.nevacuate) {
+		h.nevacuate++
+	}
+	if h.nevacuate == newbit { // newbit == # of oldbuckets
+		// Growing is all done. Free old main bucket array.
+		h.oldbuckets = nil
+		// Can discard old overflow buckets as well.
+		// If they are still referenced by an iterator,
+		// then the iterator holds a pointers to the slice.
+		if h.extra != nil {
+			h.extra.oldoverflow = nil
+		}
+		h.flags &^= sameSizeGrow
+	}
+}
+
+// Reflect stubs. Called from ../reflect/asm_*.s
+
+//go:linkname reflect_makemap reflect.makemap
+func reflect_makemap(t *maptype, cap int) *hmap {
+	// Check invariants and reflects math.
+	if t.key.equal == nil {
+		throw("runtime.reflect_makemap: unsupported map key type")
+	}
+	if t.key.size > maxKeySize && (!t.indirectkey() || t.keysize != uint8(goarch.PtrSize)) ||
+		t.key.size <= maxKeySize && (t.indirectkey() || t.keysize != uint8(t.key.size)) {
+		throw("key size wrong")
+	}
+	if t.elem.size > maxElemSize && (!t.indirectelem() || t.elemsize != uint8(goarch.PtrSize)) ||
+		t.elem.size <= maxElemSize && (t.indirectelem() || t.elemsize != uint8(t.elem.size)) {
+		throw("elem size wrong")
+	}
+	if t.key.align > bucketCnt {
+		throw("key align too big")
+	}
+	if t.elem.align > bucketCnt {
+		throw("elem align too big")
+	}
+	if t.key.size%uintptr(t.key.align) != 0 {
+		throw("key size not a multiple of key align")
+	}
+	if t.elem.size%uintptr(t.elem.align) != 0 {
+		throw("elem size not a multiple of elem align")
+	}
+	if bucketCnt < 8 {
+		throw("bucketsize too small for proper alignment")
+	}
+	if dataOffset%uintptr(t.key.align) != 0 {
+		throw("need padding in bucket (key)")
+	}
+	if dataOffset%uintptr(t.elem.align) != 0 {
+		throw("need padding in bucket (elem)")
+	}
+
+	return makemap(t, cap, nil)
+}
+
+//go:linkname reflect_mapaccess reflect.mapaccess
+func reflect_mapaccess(t *maptype, h *hmap, key unsafe.Pointer) unsafe.Pointer {
+	elem, ok := mapaccess2(t, h, key)
+	if !ok {
+		// reflect wants nil for a missing element
+		elem = nil
+	}
+	return elem
+}
+
+//go:linkname reflect_mapaccess_faststr reflect.mapaccess_faststr
+func reflect_mapaccess_faststr(t *maptype, h *hmap, key string) unsafe.Pointer {
+	elem, ok := mapaccess2_faststr(t, h, key)
+	if !ok {
+		// reflect wants nil for a missing element
+		elem = nil
+	}
+	return elem
+}
+
+//go:linkname reflect_mapassign reflect.mapassign
+func reflect_mapassign(t *maptype, h *hmap, key unsafe.Pointer, elem unsafe.Pointer) {
+	p := mapassign(t, h, key)
+	typedmemmove(t.elem, p, elem)
+}
+
+//go:linkname reflect_mapassign_faststr reflect.mapassign_faststr
+func reflect_mapassign_faststr(t *maptype, h *hmap, key string, elem unsafe.Pointer) {
+	p := mapassign_faststr(t, h, key)
+	typedmemmove(t.elem, p, elem)
+}
+
+//go:linkname reflect_mapdelete reflect.mapdelete
+func reflect_mapdelete(t *maptype, h *hmap, key unsafe.Pointer) {
+	mapdelete(t, h, key)
+}
+
+//go:linkname reflect_mapdelete_faststr reflect.mapdelete_faststr
+func reflect_mapdelete_faststr(t *maptype, h *hmap, key string) {
+	mapdelete_faststr(t, h, key)
+}
+
+//go:linkname reflect_mapiterinit reflect.mapiterinit
+func reflect_mapiterinit(t *maptype, h *hmap, it *hiter) {
+	mapiterinit(t, h, it)
+}
+
+//go:linkname reflect_mapiternext reflect.mapiternext
+func reflect_mapiternext(it *hiter) {
+	mapiternext(it)
+}
+
+//go:linkname reflect_mapiterkey reflect.mapiterkey
+func reflect_mapiterkey(it *hiter) unsafe.Pointer {
+	return it.key
+}
+
+//go:linkname reflect_mapiterelem reflect.mapiterelem
+func reflect_mapiterelem(it *hiter) unsafe.Pointer {
+	return it.elem
+}
+
+//go:linkname reflect_maplen reflect.maplen
+func reflect_maplen(h *hmap) int {
+	if h == nil {
+		return 0
+	}
+	if raceenabled {
+		callerpc := getcallerpc()
+		racereadpc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(reflect_maplen))
+	}
+	return h.count
+}
+
+//go:linkname reflectlite_maplen internal/reflectlite.maplen
+func reflectlite_maplen(h *hmap) int {
+	if h == nil {
+		return 0
+	}
+	if raceenabled {
+		callerpc := getcallerpc()
+		racereadpc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(reflect_maplen))
+	}
+	return h.count
+}
+
+const maxZero = 1024 // must match value in reflect/value.go:maxZero cmd/compile/internal/gc/walk.go:zeroValSize
+var zeroVal [maxZero]byte
diff --git a/contrib/go/_std_1.19/src/runtime/map_fast32.go b/contrib/go/_std_1.19/src/runtime/map_fast32.go
new file mode 100644
index 0000000000..01ea330950
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/map_fast32.go
@@ -0,0 +1,462 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"internal/abi"
+	"internal/goarch"
+	"unsafe"
+)
+
+func mapaccess1_fast32(t *maptype, h *hmap, key uint32) unsafe.Pointer {
+	if raceenabled && h != nil {
+		callerpc := getcallerpc()
+		racereadpc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapaccess1_fast32))
+	}
+	if h == nil || h.count == 0 {
+		return unsafe.Pointer(&zeroVal[0])
+	}
+	if h.flags&hashWriting != 0 {
+		fatal("concurrent map read and map write")
+	}
+	var b *bmap
+	if h.B == 0 {
+		// One-bucket table. No need to hash.
+		b = (*bmap)(h.buckets)
+	} else {
+		hash := t.hasher(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
+		m := bucketMask(h.B)
+		b = (*bmap)(add(h.buckets, (hash&m)*uintptr(t.bucketsize)))
+		if c := h.oldbuckets; c != nil {
+			if !h.sameSizeGrow() {
+				// There used to be half as many buckets; mask down one more power of two.
+				m >>= 1
+			}
+			oldb := (*bmap)(add(c, (hash&m)*uintptr(t.bucketsize)))
+			if !evacuated(oldb) {
+				b = oldb
+			}
+		}
+	}
+	for ; b != nil; b = b.overflow(t) {
+		for i, k := uintptr(0), b.keys(); i < bucketCnt; i, k = i+1, add(k, 4) {
+			if *(*uint32)(k) == key && !isEmpty(b.tophash[i]) {
+				return add(unsafe.Pointer(b), dataOffset+bucketCnt*4+i*uintptr(t.elemsize))
+			}
+		}
+	}
+	return unsafe.Pointer(&zeroVal[0])
+}
+
+func mapaccess2_fast32(t *maptype, h *hmap, key uint32) (unsafe.Pointer, bool) {
+	if raceenabled && h != nil {
+		callerpc := getcallerpc()
+		racereadpc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapaccess2_fast32))
+	}
+	if h == nil || h.count == 0 {
+		return unsafe.Pointer(&zeroVal[0]), false
+	}
+	if h.flags&hashWriting != 0 {
+		fatal("concurrent map read and map write")
+	}
+	var b *bmap
+	if h.B == 0 {
+		// One-bucket table. No need to hash.
+		b = (*bmap)(h.buckets)
+	} else {
+		hash := t.hasher(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
+		m := bucketMask(h.B)
+		b = (*bmap)(add(h.buckets, (hash&m)*uintptr(t.bucketsize)))
+		if c := h.oldbuckets; c != nil {
+			if !h.sameSizeGrow() {
+				// There used to be half as many buckets; mask down one more power of two.
+				m >>= 1
+			}
+			oldb := (*bmap)(add(c, (hash&m)*uintptr(t.bucketsize)))
+			if !evacuated(oldb) {
+				b = oldb
+			}
+		}
+	}
+	for ; b != nil; b = b.overflow(t) {
+		for i, k := uintptr(0), b.keys(); i < bucketCnt; i, k = i+1, add(k, 4) {
+			if *(*uint32)(k) == key && !isEmpty(b.tophash[i]) {
+				return add(unsafe.Pointer(b), dataOffset+bucketCnt*4+i*uintptr(t.elemsize)), true
+			}
+		}
+	}
+	return unsafe.Pointer(&zeroVal[0]), false
+}
+
+func mapassign_fast32(t *maptype, h *hmap, key uint32) unsafe.Pointer {
+	if h == nil {
+		panic(plainError("assignment to entry in nil map"))
+	}
+	if raceenabled {
+		callerpc := getcallerpc()
+		racewritepc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapassign_fast32))
+	}
+	if h.flags&hashWriting != 0 {
+		fatal("concurrent map writes")
+	}
+	hash := t.hasher(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
+
+	// Set hashWriting after calling t.hasher for consistency with mapassign.
+	h.flags ^= hashWriting
+
+	if h.buckets == nil {
+		h.buckets = newobject(t.bucket) // newarray(t.bucket, 1)
+	}
+
+again:
+	bucket := hash & bucketMask(h.B)
+	if h.growing() {
+		growWork_fast32(t, h, bucket)
+	}
+	b := (*bmap)(add(h.buckets, bucket*uintptr(t.bucketsize)))
+
+	var insertb *bmap
+	var inserti uintptr
+	var insertk unsafe.Pointer
+
+bucketloop:
+	for {
+		for i := uintptr(0); i < bucketCnt; i++ {
+			if isEmpty(b.tophash[i]) {
+				if insertb == nil {
+					inserti = i
+					insertb = b
+				}
+				if b.tophash[i] == emptyRest {
+					break bucketloop
+				}
+				continue
+			}
+			k := *((*uint32)(add(unsafe.Pointer(b), dataOffset+i*4)))
+			if k != key {
+				continue
+			}
+			inserti = i
+			insertb = b
+			goto done
+		}
+		ovf := b.overflow(t)
+		if ovf == nil {
+			break
+		}
+		b = ovf
+	}
+
+	// Did not find mapping for key. Allocate new cell & add entry.
+
+	// If we hit the max load factor or we have too many overflow buckets,
+	// and we're not already in the middle of growing, start growing.
+	if !h.growing() && (overLoadFactor(h.count+1, h.B) || tooManyOverflowBuckets(h.noverflow, h.B)) {
+		hashGrow(t, h)
+		goto again // Growing the table invalidates everything, so try again
+	}
+
+	if insertb == nil {
+		// The current bucket and all the overflow buckets connected to it are full, allocate a new one.
+		insertb = h.newoverflow(t, b)
+		inserti = 0 // not necessary, but avoids needlessly spilling inserti
+	}
+	insertb.tophash[inserti&(bucketCnt-1)] = tophash(hash) // mask inserti to avoid bounds checks
+
+	insertk = add(unsafe.Pointer(insertb), dataOffset+inserti*4)
+	// store new key at insert position
+	*(*uint32)(insertk) = key
+
+	h.count++
+
+done:
+	elem := add(unsafe.Pointer(insertb), dataOffset+bucketCnt*4+inserti*uintptr(t.elemsize))
+	if h.flags&hashWriting == 0 {
+		fatal("concurrent map writes")
+	}
+	h.flags &^= hashWriting
+	return elem
+}
+
+func mapassign_fast32ptr(t *maptype, h *hmap, key unsafe.Pointer) unsafe.Pointer {
+	if h == nil {
+		panic(plainError("assignment to entry in nil map"))
+	}
+	if raceenabled {
+		callerpc := getcallerpc()
+		racewritepc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapassign_fast32))
+	}
+	if h.flags&hashWriting != 0 {
+		fatal("concurrent map writes")
+	}
+	hash := t.hasher(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
+
+	// Set hashWriting after calling t.hasher for consistency with mapassign.
+	h.flags ^= hashWriting
+
+	if h.buckets == nil {
+		h.buckets = newobject(t.bucket) // newarray(t.bucket, 1)
+	}
+
+again:
+	bucket := hash & bucketMask(h.B)
+	if h.growing() {
+		growWork_fast32(t, h, bucket)
+	}
+	b := (*bmap)(add(h.buckets, bucket*uintptr(t.bucketsize)))
+
+	var insertb *bmap
+	var inserti uintptr
+	var insertk unsafe.Pointer
+
+bucketloop:
+	for {
+		for i := uintptr(0); i < bucketCnt; i++ {
+			if isEmpty(b.tophash[i]) {
+				if insertb == nil {
+					inserti = i
+					insertb = b
+				}
+				if b.tophash[i] == emptyRest {
+					break bucketloop
+				}
+				continue
+			}
+			k := *((*unsafe.Pointer)(add(unsafe.Pointer(b), dataOffset+i*4)))
+			if k != key {
+				continue
+			}
+			inserti = i
+			insertb = b
+			goto done
+		}
+		ovf := b.overflow(t)
+		if ovf == nil {
+			break
+		}
+		b = ovf
+	}
+
+	// Did not find mapping for key. Allocate new cell & add entry.
+
+	// If we hit the max load factor or we have too many overflow buckets,
+	// and we're not already in the middle of growing, start growing.
+	if !h.growing() && (overLoadFactor(h.count+1, h.B) || tooManyOverflowBuckets(h.noverflow, h.B)) {
+		hashGrow(t, h)
+		goto again // Growing the table invalidates everything, so try again
+	}
+
+	if insertb == nil {
+		// The current bucket and all the overflow buckets connected to it are full, allocate a new one.
+		insertb = h.newoverflow(t, b)
+		inserti = 0 // not necessary, but avoids needlessly spilling inserti
+	}
+	insertb.tophash[inserti&(bucketCnt-1)] = tophash(hash) // mask inserti to avoid bounds checks
+
+	insertk = add(unsafe.Pointer(insertb), dataOffset+inserti*4)
+	// store new key at insert position
+	*(*unsafe.Pointer)(insertk) = key
+
+	h.count++
+
+done:
+	elem := add(unsafe.Pointer(insertb), dataOffset+bucketCnt*4+inserti*uintptr(t.elemsize))
+	if h.flags&hashWriting == 0 {
+		fatal("concurrent map writes")
+	}
+	h.flags &^= hashWriting
+	return elem
+}
+
+func mapdelete_fast32(t *maptype, h *hmap, key uint32) {
+	if raceenabled && h != nil {
+		callerpc := getcallerpc()
+		racewritepc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapdelete_fast32))
+	}
+	if h == nil || h.count == 0 {
+		return
+	}
+	if h.flags&hashWriting != 0 {
+		fatal("concurrent map writes")
+	}
+
+	hash := t.hasher(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
+
+	// Set hashWriting after calling t.hasher for consistency with mapdelete
+	h.flags ^= hashWriting
+
+	bucket := hash & bucketMask(h.B)
+	if h.growing() {
+		growWork_fast32(t, h, bucket)
+	}
+	b := (*bmap)(add(h.buckets, bucket*uintptr(t.bucketsize)))
+	bOrig := b
+search:
+	for ; b != nil; b = b.overflow(t) {
+		for i, k := uintptr(0), b.keys(); i < bucketCnt; i, k = i+1, add(k, 4) {
+			if key != *(*uint32)(k) || isEmpty(b.tophash[i]) {
+				continue
+			}
+			// Only clear key if there are pointers in it.
+			// This can only happen if pointers are 32 bit
+			// wide as 64 bit pointers do not fit into a 32 bit key.
+			if goarch.PtrSize == 4 && t.key.ptrdata != 0 {
+				// The key must be a pointer as we checked pointers are
+				// 32 bits wide and the key is 32 bits wide also.
+				*(*unsafe.Pointer)(k) = nil
+			}
+			e := add(unsafe.Pointer(b), dataOffset+bucketCnt*4+i*uintptr(t.elemsize))
+			if t.elem.ptrdata != 0 {
+				memclrHasPointers(e, t.elem.size)
+			} else {
+				memclrNoHeapPointers(e, t.elem.size)
+			}
+			b.tophash[i] = emptyOne
+			// If the bucket now ends in a bunch of emptyOne states,
+			// change those to emptyRest states.
+			if i == bucketCnt-1 {
+				if b.overflow(t) != nil && b.overflow(t).tophash[0] != emptyRest {
+					goto notLast
+				}
+			} else {
+				if b.tophash[i+1] != emptyRest {
+					goto notLast
+				}
+			}
+			for {
+				b.tophash[i] = emptyRest
+				if i == 0 {
+					if b == bOrig {
+						break // beginning of initial bucket, we're done.
+					}
+					// Find previous bucket, continue at its last entry.
+					c := b
+					for b = bOrig; b.overflow(t) != c; b = b.overflow(t) {
+					}
+					i = bucketCnt - 1
+				} else {
+					i--
+				}
+				if b.tophash[i] != emptyOne {
+					break
+				}
+			}
+		notLast:
+			h.count--
+			// Reset the hash seed to make it more difficult for attackers to
+			// repeatedly trigger hash collisions. See issue 25237.
+			if h.count == 0 {
+				h.hash0 = fastrand()
+			}
+			break search
+		}
+	}
+
+	if h.flags&hashWriting == 0 {
+		fatal("concurrent map writes")
+	}
+	h.flags &^= hashWriting
+}
+
+func growWork_fast32(t *maptype, h *hmap, bucket uintptr) {
+	// make sure we evacuate the oldbucket corresponding
+	// to the bucket we're about to use
+	evacuate_fast32(t, h, bucket&h.oldbucketmask())
+
+	// evacuate one more oldbucket to make progress on growing
+	if h.growing() {
+		evacuate_fast32(t, h, h.nevacuate)
+	}
+}
+
+func evacuate_fast32(t *maptype, h *hmap, oldbucket uintptr) {
+	b := (*bmap)(add(h.oldbuckets, oldbucket*uintptr(t.bucketsize)))
+	newbit := h.noldbuckets()
+	if !evacuated(b) {
+		// TODO: reuse overflow buckets instead of using new ones, if there
+		// is no iterator using the old buckets.  (If !oldIterator.)
+
+		// xy contains the x and y (low and high) evacuation destinations.
+		var xy [2]evacDst
+		x := &xy[0]
+		x.b = (*bmap)(add(h.buckets, oldbucket*uintptr(t.bucketsize)))
+		x.k = add(unsafe.Pointer(x.b), dataOffset)
+		x.e = add(x.k, bucketCnt*4)
+
+		if !h.sameSizeGrow() {
+			// Only calculate y pointers if we're growing bigger.
+			// Otherwise GC can see bad pointers.
+			y := &xy[1]
+			y.b = (*bmap)(add(h.buckets, (oldbucket+newbit)*uintptr(t.bucketsize)))
+			y.k = add(unsafe.Pointer(y.b), dataOffset)
+			y.e = add(y.k, bucketCnt*4)
+		}
+
+		for ; b != nil; b = b.overflow(t) {
+			k := add(unsafe.Pointer(b), dataOffset)
+			e := add(k, bucketCnt*4)
+			for i := 0; i < bucketCnt; i, k, e = i+1, add(k, 4), add(e, uintptr(t.elemsize)) {
+				top := b.tophash[i]
+				if isEmpty(top) {
+					b.tophash[i] = evacuatedEmpty
+					continue
+				}
+				if top < minTopHash {
+					throw("bad map state")
+				}
+				var useY uint8
+				if !h.sameSizeGrow() {
+					// Compute hash to make our evacuation decision (whether we need
+					// to send this key/elem to bucket x or bucket y).
+					hash := t.hasher(k, uintptr(h.hash0))
+					if hash&newbit != 0 {
+						useY = 1
+					}
+				}
+
+				b.tophash[i] = evacuatedX + useY // evacuatedX + 1 == evacuatedY, enforced in makemap
+				dst := &xy[useY]                 // evacuation destination
+
+				if dst.i == bucketCnt {
+					dst.b = h.newoverflow(t, dst.b)
+					dst.i = 0
+					dst.k = add(unsafe.Pointer(dst.b), dataOffset)
+					dst.e = add(dst.k, bucketCnt*4)
+				}
+				dst.b.tophash[dst.i&(bucketCnt-1)] = top // mask dst.i as an optimization, to avoid a bounds check
+
+				// Copy key.
+				if goarch.PtrSize == 4 && t.key.ptrdata != 0 && writeBarrier.enabled {
+					// Write with a write barrier.
+					*(*unsafe.Pointer)(dst.k) = *(*unsafe.Pointer)(k)
+				} else {
+					*(*uint32)(dst.k) = *(*uint32)(k)
+				}
+
+				typedmemmove(t.elem, dst.e, e)
+				dst.i++
+				// These updates might push these pointers past the end of the
+				// key or elem arrays.  That's ok, as we have the overflow pointer
+				// at the end of the bucket to protect against pointing past the
+				// end of the bucket.
+				dst.k = add(dst.k, 4)
+				dst.e = add(dst.e, uintptr(t.elemsize))
+			}
+		}
+		// Unlink the overflow buckets & clear key/elem to help GC.
+		if h.flags&oldIterator == 0 && t.bucket.ptrdata != 0 {
+			b := add(h.oldbuckets, oldbucket*uintptr(t.bucketsize))
+			// Preserve b.tophash because the evacuation
+			// state is maintained there.
+			ptr := add(b, dataOffset)
+			n := uintptr(t.bucketsize) - dataOffset
+			memclrHasPointers(ptr, n)
+		}
+	}
+
+	if oldbucket == h.nevacuate {
+		advanceEvacuationMark(h, t, newbit)
+	}
+}
diff --git a/contrib/go/_std_1.19/src/runtime/map_fast64.go b/contrib/go/_std_1.19/src/runtime/map_fast64.go
new file mode 100644
index 0000000000..2967360b76
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/map_fast64.go
@@ -0,0 +1,470 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"internal/abi"
+	"internal/goarch"
+	"unsafe"
+)
+
+func mapaccess1_fast64(t *maptype, h *hmap, key uint64) unsafe.Pointer {
+	if raceenabled && h != nil {
+		callerpc := getcallerpc()
+		racereadpc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapaccess1_fast64))
+	}
+	if h == nil || h.count == 0 {
+		return unsafe.Pointer(&zeroVal[0])
+	}
+	if h.flags&hashWriting != 0 {
+		fatal("concurrent map read and map write")
+	}
+	var b *bmap
+	if h.B == 0 {
+		// One-bucket table. No need to hash.
+		b = (*bmap)(h.buckets)
+	} else {
+		hash := t.hasher(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
+		m := bucketMask(h.B)
+		b = (*bmap)(add(h.buckets, (hash&m)*uintptr(t.bucketsize)))
+		if c := h.oldbuckets; c != nil {
+			if !h.sameSizeGrow() {
+				// There used to be half as many buckets; mask down one more power of two.
+				m >>= 1
+			}
+			oldb := (*bmap)(add(c, (hash&m)*uintptr(t.bucketsize)))
+			if !evacuated(oldb) {
+				b = oldb
+			}
+		}
+	}
+	for ; b != nil; b = b.overflow(t) {
+		for i, k := uintptr(0), b.keys(); i < bucketCnt; i, k = i+1, add(k, 8) {
+			if *(*uint64)(k) == key && !isEmpty(b.tophash[i]) {
+				return add(unsafe.Pointer(b), dataOffset+bucketCnt*8+i*uintptr(t.elemsize))
+			}
+		}
+	}
+	return unsafe.Pointer(&zeroVal[0])
+}
+
+func mapaccess2_fast64(t *maptype, h *hmap, key uint64) (unsafe.Pointer, bool) {
+	if raceenabled && h != nil {
+		callerpc := getcallerpc()
+		racereadpc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapaccess2_fast64))
+	}
+	if h == nil || h.count == 0 {
+		return unsafe.Pointer(&zeroVal[0]), false
+	}
+	if h.flags&hashWriting != 0 {
+		fatal("concurrent map read and map write")
+	}
+	var b *bmap
+	if h.B == 0 {
+		// One-bucket table. No need to hash.
+		b = (*bmap)(h.buckets)
+	} else {
+		hash := t.hasher(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
+		m := bucketMask(h.B)
+		b = (*bmap)(add(h.buckets, (hash&m)*uintptr(t.bucketsize)))
+		if c := h.oldbuckets; c != nil {
+			if !h.sameSizeGrow() {
+				// There used to be half as many buckets; mask down one more power of two.
+				m >>= 1
+			}
+			oldb := (*bmap)(add(c, (hash&m)*uintptr(t.bucketsize)))
+			if !evacuated(oldb) {
+				b = oldb
+			}
+		}
+	}
+	for ; b != nil; b = b.overflow(t) {
+		for i, k := uintptr(0), b.keys(); i < bucketCnt; i, k = i+1, add(k, 8) {
+			if *(*uint64)(k) == key && !isEmpty(b.tophash[i]) {
+				return add(unsafe.Pointer(b), dataOffset+bucketCnt*8+i*uintptr(t.elemsize)), true
+			}
+		}
+	}
+	return unsafe.Pointer(&zeroVal[0]), false
+}
+
+func mapassign_fast64(t *maptype, h *hmap, key uint64) unsafe.Pointer {
+	if h == nil {
+		panic(plainError("assignment to entry in nil map"))
+	}
+	if raceenabled {
+		callerpc := getcallerpc()
+		racewritepc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapassign_fast64))
+	}
+	if h.flags&hashWriting != 0 {
+		fatal("concurrent map writes")
+	}
+	hash := t.hasher(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
+
+	// Set hashWriting after calling t.hasher for consistency with mapassign.
+	h.flags ^= hashWriting
+
+	if h.buckets == nil {
+		h.buckets = newobject(t.bucket) // newarray(t.bucket, 1)
+	}
+
+again:
+	bucket := hash & bucketMask(h.B)
+	if h.growing() {
+		growWork_fast64(t, h, bucket)
+	}
+	b := (*bmap)(add(h.buckets, bucket*uintptr(t.bucketsize)))
+
+	var insertb *bmap
+	var inserti uintptr
+	var insertk unsafe.Pointer
+
+bucketloop:
+	for {
+		for i := uintptr(0); i < bucketCnt; i++ {
+			if isEmpty(b.tophash[i]) {
+				if insertb == nil {
+					insertb = b
+					inserti = i
+				}
+				if b.tophash[i] == emptyRest {
+					break bucketloop
+				}
+				continue
+			}
+			k := *((*uint64)(add(unsafe.Pointer(b), dataOffset+i*8)))
+			if k != key {
+				continue
+			}
+			insertb = b
+			inserti = i
+			goto done
+		}
+		ovf := b.overflow(t)
+		if ovf == nil {
+			break
+		}
+		b = ovf
+	}
+
+	// Did not find mapping for key. Allocate new cell & add entry.
+
+	// If we hit the max load factor or we have too many overflow buckets,
+	// and we're not already in the middle of growing, start growing.
+	if !h.growing() && (overLoadFactor(h.count+1, h.B) || tooManyOverflowBuckets(h.noverflow, h.B)) {
+		hashGrow(t, h)
+		goto again // Growing the table invalidates everything, so try again
+	}
+
+	if insertb == nil {
+		// The current bucket and all the overflow buckets connected to it are full, allocate a new one.
+		insertb = h.newoverflow(t, b)
+		inserti = 0 // not necessary, but avoids needlessly spilling inserti
+	}
+	insertb.tophash[inserti&(bucketCnt-1)] = tophash(hash) // mask inserti to avoid bounds checks
+
+	insertk = add(unsafe.Pointer(insertb), dataOffset+inserti*8)
+	// store new key at insert position
+	*(*uint64)(insertk) = key
+
+	h.count++
+
+done:
+	elem := add(unsafe.Pointer(insertb), dataOffset+bucketCnt*8+inserti*uintptr(t.elemsize))
+	if h.flags&hashWriting == 0 {
+		fatal("concurrent map writes")
+	}
+	h.flags &^= hashWriting
+	return elem
+}
+
+func mapassign_fast64ptr(t *maptype, h *hmap, key unsafe.Pointer) unsafe.Pointer {
+	if h == nil {
+		panic(plainError("assignment to entry in nil map"))
+	}
+	if raceenabled {
+		callerpc := getcallerpc()
+		racewritepc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapassign_fast64))
+	}
+	if h.flags&hashWriting != 0 {
+		fatal("concurrent map writes")
+	}
+	hash := t.hasher(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
+
+	// Set hashWriting after calling t.hasher for consistency with mapassign.
+	h.flags ^= hashWriting
+
+	if h.buckets == nil {
+		h.buckets = newobject(t.bucket) // newarray(t.bucket, 1)
+	}
+
+again:
+	bucket := hash & bucketMask(h.B)
+	if h.growing() {
+		growWork_fast64(t, h, bucket)
+	}
+	b := (*bmap)(add(h.buckets, bucket*uintptr(t.bucketsize)))
+
+	var insertb *bmap
+	var inserti uintptr
+	var insertk unsafe.Pointer
+
+bucketloop:
+	for {
+		for i := uintptr(0); i < bucketCnt; i++ {
+			if isEmpty(b.tophash[i]) {
+				if insertb == nil {
+					insertb = b
+					inserti = i
+				}
+				if b.tophash[i] == emptyRest {
+					break bucketloop
+				}
+				continue
+			}
+			k := *((*unsafe.Pointer)(add(unsafe.Pointer(b), dataOffset+i*8)))
+			if k != key {
+				continue
+			}
+			insertb = b
+			inserti = i
+			goto done
+		}
+		ovf := b.overflow(t)
+		if ovf == nil {
+			break
+		}
+		b = ovf
+	}
+
+	// Did not find mapping for key. Allocate new cell & add entry.
+
+	// If we hit the max load factor or we have too many overflow buckets,
+	// and we're not already in the middle of growing, start growing.
+	if !h.growing() && (overLoadFactor(h.count+1, h.B) || tooManyOverflowBuckets(h.noverflow, h.B)) {
+		hashGrow(t, h)
+		goto again // Growing the table invalidates everything, so try again
+	}
+
+	if insertb == nil {
+		// The current bucket and all the overflow buckets connected to it are full, allocate a new one.
+		insertb = h.newoverflow(t, b)
+		inserti = 0 // not necessary, but avoids needlessly spilling inserti
+	}
+	insertb.tophash[inserti&(bucketCnt-1)] = tophash(hash) // mask inserti to avoid bounds checks
+
+	insertk = add(unsafe.Pointer(insertb), dataOffset+inserti*8)
+	// store new key at insert position
+	*(*unsafe.Pointer)(insertk) = key
+
+	h.count++
+
+done:
+	elem := add(unsafe.Pointer(insertb), dataOffset+bucketCnt*8+inserti*uintptr(t.elemsize))
+	if h.flags&hashWriting == 0 {
+		fatal("concurrent map writes")
+	}
+	h.flags &^= hashWriting
+	return elem
+}
+
+func mapdelete_fast64(t *maptype, h *hmap, key uint64) {
+	if raceenabled && h != nil {
+		callerpc := getcallerpc()
+		racewritepc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapdelete_fast64))
+	}
+	if h == nil || h.count == 0 {
+		return
+	}
+	if h.flags&hashWriting != 0 {
+		fatal("concurrent map writes")
+	}
+
+	hash := t.hasher(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
+
+	// Set hashWriting after calling t.hasher for consistency with mapdelete
+	h.flags ^= hashWriting
+
+	bucket := hash & bucketMask(h.B)
+	if h.growing() {
+		growWork_fast64(t, h, bucket)
+	}
+	b := (*bmap)(add(h.buckets, bucket*uintptr(t.bucketsize)))
+	bOrig := b
+search:
+	for ; b != nil; b = b.overflow(t) {
+		for i, k := uintptr(0), b.keys(); i < bucketCnt; i, k = i+1, add(k, 8) {
+			if key != *(*uint64)(k) || isEmpty(b.tophash[i]) {
+				continue
+			}
+			// Only clear key if there are pointers in it.
+			if t.key.ptrdata != 0 {
+				if goarch.PtrSize == 8 {
+					*(*unsafe.Pointer)(k) = nil
+				} else {
+					// There are three ways to squeeze at one ore more 32 bit pointers into 64 bits.
+					// Just call memclrHasPointers instead of trying to handle all cases here.
+					memclrHasPointers(k, 8)
+				}
+			}
+			e := add(unsafe.Pointer(b), dataOffset+bucketCnt*8+i*uintptr(t.elemsize))
+			if t.elem.ptrdata != 0 {
+				memclrHasPointers(e, t.elem.size)
+			} else {
+				memclrNoHeapPointers(e, t.elem.size)
+			}
+			b.tophash[i] = emptyOne
+			// If the bucket now ends in a bunch of emptyOne states,
+			// change those to emptyRest states.
+			if i == bucketCnt-1 {
+				if b.overflow(t) != nil && b.overflow(t).tophash[0] != emptyRest {
+					goto notLast
+				}
+			} else {
+				if b.tophash[i+1] != emptyRest {
+					goto notLast
+				}
+			}
+			for {
+				b.tophash[i] = emptyRest
+				if i == 0 {
+					if b == bOrig {
+						break // beginning of initial bucket, we're done.
+					}
+					// Find previous bucket, continue at its last entry.
+					c := b
+					for b = bOrig; b.overflow(t) != c; b = b.overflow(t) {
+					}
+					i = bucketCnt - 1
+				} else {
+					i--
+				}
+				if b.tophash[i] != emptyOne {
+					break
+				}
+			}
+		notLast:
+			h.count--
+			// Reset the hash seed to make it more difficult for attackers to
+			// repeatedly trigger hash collisions. See issue 25237.
+			if h.count == 0 {
+				h.hash0 = fastrand()
+			}
+			break search
+		}
+	}
+
+	if h.flags&hashWriting == 0 {
+		fatal("concurrent map writes")
+	}
+	h.flags &^= hashWriting
+}
+
+func growWork_fast64(t *maptype, h *hmap, bucket uintptr) {
+	// make sure we evacuate the oldbucket corresponding
+	// to the bucket we're about to use
+	evacuate_fast64(t, h, bucket&h.oldbucketmask())
+
+	// evacuate one more oldbucket to make progress on growing
+	if h.growing() {
+		evacuate_fast64(t, h, h.nevacuate)
+	}
+}
+
+func evacuate_fast64(t *maptype, h *hmap, oldbucket uintptr) {
+	b := (*bmap)(add(h.oldbuckets, oldbucket*uintptr(t.bucketsize)))
+	newbit := h.noldbuckets()
+	if !evacuated(b) {
+		// TODO: reuse overflow buckets instead of using new ones, if there
+		// is no iterator using the old buckets.  (If !oldIterator.)
+
+		// xy contains the x and y (low and high) evacuation destinations.
+		var xy [2]evacDst
+		x := &xy[0]
+		x.b = (*bmap)(add(h.buckets, oldbucket*uintptr(t.bucketsize)))
+		x.k = add(unsafe.Pointer(x.b), dataOffset)
+		x.e = add(x.k, bucketCnt*8)
+
+		if !h.sameSizeGrow() {
+			// Only calculate y pointers if we're growing bigger.
+			// Otherwise GC can see bad pointers.
+			y := &xy[1]
+			y.b = (*bmap)(add(h.buckets, (oldbucket+newbit)*uintptr(t.bucketsize)))
+			y.k = add(unsafe.Pointer(y.b), dataOffset)
+			y.e = add(y.k, bucketCnt*8)
+		}
+
+		for ; b != nil; b = b.overflow(t) {
+			k := add(unsafe.Pointer(b), dataOffset)
+			e := add(k, bucketCnt*8)
+			for i := 0; i < bucketCnt; i, k, e = i+1, add(k, 8), add(e, uintptr(t.elemsize)) {
+				top := b.tophash[i]
+				if isEmpty(top) {
+					b.tophash[i] = evacuatedEmpty
+					continue
+				}
+				if top < minTopHash {
+					throw("bad map state")
+				}
+				var useY uint8
+				if !h.sameSizeGrow() {
+					// Compute hash to make our evacuation decision (whether we need
+					// to send this key/elem to bucket x or bucket y).
+					hash := t.hasher(k, uintptr(h.hash0))
+					if hash&newbit != 0 {
+						useY = 1
+					}
+				}
+
+				b.tophash[i] = evacuatedX + useY // evacuatedX + 1 == evacuatedY, enforced in makemap
+				dst := &xy[useY]                 // evacuation destination
+
+				if dst.i == bucketCnt {
+					dst.b = h.newoverflow(t, dst.b)
+					dst.i = 0
+					dst.k = add(unsafe.Pointer(dst.b), dataOffset)
+					dst.e = add(dst.k, bucketCnt*8)
+				}
+				dst.b.tophash[dst.i&(bucketCnt-1)] = top // mask dst.i as an optimization, to avoid a bounds check
+
+				// Copy key.
+				if t.key.ptrdata != 0 && writeBarrier.enabled {
+					if goarch.PtrSize == 8 {
+						// Write with a write barrier.
+						*(*unsafe.Pointer)(dst.k) = *(*unsafe.Pointer)(k)
+					} else {
+						// There are three ways to squeeze at least one 32 bit pointer into 64 bits.
+						// Give up and call typedmemmove.
+						typedmemmove(t.key, dst.k, k)
+					}
+				} else {
+					*(*uint64)(dst.k) = *(*uint64)(k)
+				}
+
+				typedmemmove(t.elem, dst.e, e)
+				dst.i++
+				// These updates might push these pointers past the end of the
+				// key or elem arrays.  That's ok, as we have the overflow pointer
+				// at the end of the bucket to protect against pointing past the
+				// end of the bucket.
+				dst.k = add(dst.k, 8)
+				dst.e = add(dst.e, uintptr(t.elemsize))
+			}
+		}
+		// Unlink the overflow buckets & clear key/elem to help GC.
+		if h.flags&oldIterator == 0 && t.bucket.ptrdata != 0 {
+			b := add(h.oldbuckets, oldbucket*uintptr(t.bucketsize))
+			// Preserve b.tophash because the evacuation
+			// state is maintained there.
+			ptr := add(b, dataOffset)
+			n := uintptr(t.bucketsize) - dataOffset
+			memclrHasPointers(ptr, n)
+		}
+	}
+
+	if oldbucket == h.nevacuate {
+		advanceEvacuationMark(h, t, newbit)
+	}
+}
diff --git a/contrib/go/_std_1.19/src/runtime/map_faststr.go b/contrib/go/_std_1.19/src/runtime/map_faststr.go
new file mode 100644
index 0000000000..006c24cee2
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/map_faststr.go
@@ -0,0 +1,485 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"internal/abi"
+	"internal/goarch"
+	"unsafe"
+)
+
+func mapaccess1_faststr(t *maptype, h *hmap, ky string) unsafe.Pointer {
+	if raceenabled && h != nil {
+		callerpc := getcallerpc()
+		racereadpc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapaccess1_faststr))
+	}
+	if h == nil || h.count == 0 {
+		return unsafe.Pointer(&zeroVal[0])
+	}
+	if h.flags&hashWriting != 0 {
+		fatal("concurrent map read and map write")
+	}
+	key := stringStructOf(&ky)
+	if h.B == 0 {
+		// One-bucket table.
+		b := (*bmap)(h.buckets)
+		if key.len < 32 {
+			// short key, doing lots of comparisons is ok
+			for i, kptr := uintptr(0), b.keys(); i < bucketCnt; i, kptr = i+1, add(kptr, 2*goarch.PtrSize) {
+				k := (*stringStruct)(kptr)
+				if k.len != key.len || isEmpty(b.tophash[i]) {
+					if b.tophash[i] == emptyRest {
+						break
+					}
+					continue
+				}
+				if k.str == key.str || memequal(k.str, key.str, uintptr(key.len)) {
+					return add(unsafe.Pointer(b), dataOffset+bucketCnt*2*goarch.PtrSize+i*uintptr(t.elemsize))
+				}
+			}
+			return unsafe.Pointer(&zeroVal[0])
+		}
+		// long key, try not to do more comparisons than necessary
+		keymaybe := uintptr(bucketCnt)
+		for i, kptr := uintptr(0), b.keys(); i < bucketCnt; i, kptr = i+1, add(kptr, 2*goarch.PtrSize) {
+			k := (*stringStruct)(kptr)
+			if k.len != key.len || isEmpty(b.tophash[i]) {
+				if b.tophash[i] == emptyRest {
+					break
+				}
+				continue
+			}
+			if k.str == key.str {
+				return add(unsafe.Pointer(b), dataOffset+bucketCnt*2*goarch.PtrSize+i*uintptr(t.elemsize))
+			}
+			// check first 4 bytes
+			if *((*[4]byte)(key.str)) != *((*[4]byte)(k.str)) {
+				continue
+			}
+			// check last 4 bytes
+			if *((*[4]byte)(add(key.str, uintptr(key.len)-4))) != *((*[4]byte)(add(k.str, uintptr(key.len)-4))) {
+				continue
+			}
+			if keymaybe != bucketCnt {
+				// Two keys are potential matches. Use hash to distinguish them.
+				goto dohash
+			}
+			keymaybe = i
+		}
+		if keymaybe != bucketCnt {
+			k := (*stringStruct)(add(unsafe.Pointer(b), dataOffset+keymaybe*2*goarch.PtrSize))
+			if memequal(k.str, key.str, uintptr(key.len)) {
+				return add(unsafe.Pointer(b), dataOffset+bucketCnt*2*goarch.PtrSize+keymaybe*uintptr(t.elemsize))
+			}
+		}
+		return unsafe.Pointer(&zeroVal[0])
+	}
+dohash:
+	hash := t.hasher(noescape(unsafe.Pointer(&ky)), uintptr(h.hash0))
+	m := bucketMask(h.B)
+	b := (*bmap)(add(h.buckets, (hash&m)*uintptr(t.bucketsize)))
+	if c := h.oldbuckets; c != nil {
+		if !h.sameSizeGrow() {
+			// There used to be half as many buckets; mask down one more power of two.
+			m >>= 1
+		}
+		oldb := (*bmap)(add(c, (hash&m)*uintptr(t.bucketsize)))
+		if !evacuated(oldb) {
+			b = oldb
+		}
+	}
+	top := tophash(hash)
+	for ; b != nil; b = b.overflow(t) {
+		for i, kptr := uintptr(0), b.keys(); i < bucketCnt; i, kptr = i+1, add(kptr, 2*goarch.PtrSize) {
+			k := (*stringStruct)(kptr)
+			if k.len != key.len || b.tophash[i] != top {
+				continue
+			}
+			if k.str == key.str || memequal(k.str, key.str, uintptr(key.len)) {
+				return add(unsafe.Pointer(b), dataOffset+bucketCnt*2*goarch.PtrSize+i*uintptr(t.elemsize))
+			}
+		}
+	}
+	return unsafe.Pointer(&zeroVal[0])
+}
+
+func mapaccess2_faststr(t *maptype, h *hmap, ky string) (unsafe.Pointer, bool) {
+	if raceenabled && h != nil {
+		callerpc := getcallerpc()
+		racereadpc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapaccess2_faststr))
+	}
+	if h == nil || h.count == 0 {
+		return unsafe.Pointer(&zeroVal[0]), false
+	}
+	if h.flags&hashWriting != 0 {
+		fatal("concurrent map read and map write")
+	}
+	key := stringStructOf(&ky)
+	if h.B == 0 {
+		// One-bucket table.
+		b := (*bmap)(h.buckets)
+		if key.len < 32 {
+			// short key, doing lots of comparisons is ok
+			for i, kptr := uintptr(0), b.keys(); i < bucketCnt; i, kptr = i+1, add(kptr, 2*goarch.PtrSize) {
+				k := (*stringStruct)(kptr)
+				if k.len != key.len || isEmpty(b.tophash[i]) {
+					if b.tophash[i] == emptyRest {
+						break
+					}
+					continue
+				}
+				if k.str == key.str || memequal(k.str, key.str, uintptr(key.len)) {
+					return add(unsafe.Pointer(b), dataOffset+bucketCnt*2*goarch.PtrSize+i*uintptr(t.elemsize)), true
+				}
+			}
+			return unsafe.Pointer(&zeroVal[0]), false
+		}
+		// long key, try not to do more comparisons than necessary
+		keymaybe := uintptr(bucketCnt)
+		for i, kptr := uintptr(0), b.keys(); i < bucketCnt; i, kptr = i+1, add(kptr, 2*goarch.PtrSize) {
+			k := (*stringStruct)(kptr)
+			if k.len != key.len || isEmpty(b.tophash[i]) {
+				if b.tophash[i] == emptyRest {
+					break
+				}
+				continue
+			}
+			if k.str == key.str {
+				return add(unsafe.Pointer(b), dataOffset+bucketCnt*2*goarch.PtrSize+i*uintptr(t.elemsize)), true
+			}
+			// check first 4 bytes
+			if *((*[4]byte)(key.str)) != *((*[4]byte)(k.str)) {
+				continue
+			}
+			// check last 4 bytes
+			if *((*[4]byte)(add(key.str, uintptr(key.len)-4))) != *((*[4]byte)(add(k.str, uintptr(key.len)-4))) {
+				continue
+			}
+			if keymaybe != bucketCnt {
+				// Two keys are potential matches. Use hash to distinguish them.
+				goto dohash
+			}
+			keymaybe = i
+		}
+		if keymaybe != bucketCnt {
+			k := (*stringStruct)(add(unsafe.Pointer(b), dataOffset+keymaybe*2*goarch.PtrSize))
+			if memequal(k.str, key.str, uintptr(key.len)) {
+				return add(unsafe.Pointer(b), dataOffset+bucketCnt*2*goarch.PtrSize+keymaybe*uintptr(t.elemsize)), true
+			}
+		}
+		return unsafe.Pointer(&zeroVal[0]), false
+	}
+dohash:
+	hash := t.hasher(noescape(unsafe.Pointer(&ky)), uintptr(h.hash0))
+	m := bucketMask(h.B)
+	b := (*bmap)(add(h.buckets, (hash&m)*uintptr(t.bucketsize)))
+	if c := h.oldbuckets; c != nil {
+		if !h.sameSizeGrow() {
+			// There used to be half as many buckets; mask down one more power of two.
+			m >>= 1
+		}
+		oldb := (*bmap)(add(c, (hash&m)*uintptr(t.bucketsize)))
+		if !evacuated(oldb) {
+			b = oldb
+		}
+	}
+	top := tophash(hash)
+	for ; b != nil; b = b.overflow(t) {
+		for i, kptr := uintptr(0), b.keys(); i < bucketCnt; i, kptr = i+1, add(kptr, 2*goarch.PtrSize) {
+			k := (*stringStruct)(kptr)
+			if k.len != key.len || b.tophash[i] != top {
+				continue
+			}
+			if k.str == key.str || memequal(k.str, key.str, uintptr(key.len)) {
+				return add(unsafe.Pointer(b), dataOffset+bucketCnt*2*goarch.PtrSize+i*uintptr(t.elemsize)), true
+			}
+		}
+	}
+	return unsafe.Pointer(&zeroVal[0]), false
+}
+
+func mapassign_faststr(t *maptype, h *hmap, s string) unsafe.Pointer {
+	if h == nil {
+		panic(plainError("assignment to entry in nil map"))
+	}
+	if raceenabled {
+		callerpc := getcallerpc()
+		racewritepc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapassign_faststr))
+	}
+	if h.flags&hashWriting != 0 {
+		fatal("concurrent map writes")
+	}
+	key := stringStructOf(&s)
+	hash := t.hasher(noescape(unsafe.Pointer(&s)), uintptr(h.hash0))
+
+	// Set hashWriting after calling t.hasher for consistency with mapassign.
+	h.flags ^= hashWriting
+
+	if h.buckets == nil {
+		h.buckets = newobject(t.bucket) // newarray(t.bucket, 1)
+	}
+
+again:
+	bucket := hash & bucketMask(h.B)
+	if h.growing() {
+		growWork_faststr(t, h, bucket)
+	}
+	b := (*bmap)(add(h.buckets, bucket*uintptr(t.bucketsize)))
+	top := tophash(hash)
+
+	var insertb *bmap
+	var inserti uintptr
+	var insertk unsafe.Pointer
+
+bucketloop:
+	for {
+		for i := uintptr(0); i < bucketCnt; i++ {
+			if b.tophash[i] != top {
+				if isEmpty(b.tophash[i]) && insertb == nil {
+					insertb = b
+					inserti = i
+				}
+				if b.tophash[i] == emptyRest {
+					break bucketloop
+				}
+				continue
+			}
+			k := (*stringStruct)(add(unsafe.Pointer(b), dataOffset+i*2*goarch.PtrSize))
+			if k.len != key.len {
+				continue
+			}
+			if k.str != key.str && !memequal(k.str, key.str, uintptr(key.len)) {
+				continue
+			}
+			// already have a mapping for key. Update it.
+			inserti = i
+			insertb = b
+			// Overwrite existing key, so it can be garbage collected.
+			// The size is already guaranteed to be set correctly.
+			k.str = key.str
+			goto done
+		}
+		ovf := b.overflow(t)
+		if ovf == nil {
+			break
+		}
+		b = ovf
+	}
+
+	// Did not find mapping for key. Allocate new cell & add entry.
+
+	// If we hit the max load factor or we have too many overflow buckets,
+	// and we're not already in the middle of growing, start growing.
+	if !h.growing() && (overLoadFactor(h.count+1, h.B) || tooManyOverflowBuckets(h.noverflow, h.B)) {
+		hashGrow(t, h)
+		goto again // Growing the table invalidates everything, so try again
+	}
+
+	if insertb == nil {
+		// The current bucket and all the overflow buckets connected to it are full, allocate a new one.
+		insertb = h.newoverflow(t, b)
+		inserti = 0 // not necessary, but avoids needlessly spilling inserti
+	}
+	insertb.tophash[inserti&(bucketCnt-1)] = top // mask inserti to avoid bounds checks
+
+	insertk = add(unsafe.Pointer(insertb), dataOffset+inserti*2*goarch.PtrSize)
+	// store new key at insert position
+	*((*stringStruct)(insertk)) = *key
+	h.count++
+
+done:
+	elem := add(unsafe.Pointer(insertb), dataOffset+bucketCnt*2*goarch.PtrSize+inserti*uintptr(t.elemsize))
+	if h.flags&hashWriting == 0 {
+		fatal("concurrent map writes")
+	}
+	h.flags &^= hashWriting
+	return elem
+}
+
+func mapdelete_faststr(t *maptype, h *hmap, ky string) {
+	if raceenabled && h != nil {
+		callerpc := getcallerpc()
+		racewritepc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapdelete_faststr))
+	}
+	if h == nil || h.count == 0 {
+		return
+	}
+	if h.flags&hashWriting != 0 {
+		fatal("concurrent map writes")
+	}
+
+	key := stringStructOf(&ky)
+	hash := t.hasher(noescape(unsafe.Pointer(&ky)), uintptr(h.hash0))
+
+	// Set hashWriting after calling t.hasher for consistency with mapdelete
+	h.flags ^= hashWriting
+
+	bucket := hash & bucketMask(h.B)
+	if h.growing() {
+		growWork_faststr(t, h, bucket)
+	}
+	b := (*bmap)(add(h.buckets, bucket*uintptr(t.bucketsize)))
+	bOrig := b
+	top := tophash(hash)
+search:
+	for ; b != nil; b = b.overflow(t) {
+		for i, kptr := uintptr(0), b.keys(); i < bucketCnt; i, kptr = i+1, add(kptr, 2*goarch.PtrSize) {
+			k := (*stringStruct)(kptr)
+			if k.len != key.len || b.tophash[i] != top {
+				continue
+			}
+			if k.str != key.str && !memequal(k.str, key.str, uintptr(key.len)) {
+				continue
+			}
+			// Clear key's pointer.
+			k.str = nil
+			e := add(unsafe.Pointer(b), dataOffset+bucketCnt*2*goarch.PtrSize+i*uintptr(t.elemsize))
+			if t.elem.ptrdata != 0 {
+				memclrHasPointers(e, t.elem.size)
+			} else {
+				memclrNoHeapPointers(e, t.elem.size)
+			}
+			b.tophash[i] = emptyOne
+			// If the bucket now ends in a bunch of emptyOne states,
+			// change those to emptyRest states.
+			if i == bucketCnt-1 {
+				if b.overflow(t) != nil && b.overflow(t).tophash[0] != emptyRest {
+					goto notLast
+				}
+			} else {
+				if b.tophash[i+1] != emptyRest {
+					goto notLast
+				}
+			}
+			for {
+				b.tophash[i] = emptyRest
+				if i == 0 {
+					if b == bOrig {
+						break // beginning of initial bucket, we're done.
+					}
+					// Find previous bucket, continue at its last entry.
+					c := b
+					for b = bOrig; b.overflow(t) != c; b = b.overflow(t) {
+					}
+					i = bucketCnt - 1
+				} else {
+					i--
+				}
+				if b.tophash[i] != emptyOne {
+					break
+				}
+			}
+		notLast:
+			h.count--
+			// Reset the hash seed to make it more difficult for attackers to
+			// repeatedly trigger hash collisions. See issue 25237.
+			if h.count == 0 {
+				h.hash0 = fastrand()
+			}
+			break search
+		}
+	}
+
+	if h.flags&hashWriting == 0 {
+		fatal("concurrent map writes")
+	}
+	h.flags &^= hashWriting
+}
+
+func growWork_faststr(t *maptype, h *hmap, bucket uintptr) {
+	// make sure we evacuate the oldbucket corresponding
+	// to the bucket we're about to use
+	evacuate_faststr(t, h, bucket&h.oldbucketmask())
+
+	// evacuate one more oldbucket to make progress on growing
+	if h.growing() {
+		evacuate_faststr(t, h, h.nevacuate)
+	}
+}
+
+func evacuate_faststr(t *maptype, h *hmap, oldbucket uintptr) {
+	b := (*bmap)(add(h.oldbuckets, oldbucket*uintptr(t.bucketsize)))
+	newbit := h.noldbuckets()
+	if !evacuated(b) {
+		// TODO: reuse overflow buckets instead of using new ones, if there
+		// is no iterator using the old buckets.  (If !oldIterator.)
+
+		// xy contains the x and y (low and high) evacuation destinations.
+		var xy [2]evacDst
+		x := &xy[0]
+		x.b = (*bmap)(add(h.buckets, oldbucket*uintptr(t.bucketsize)))
+		x.k = add(unsafe.Pointer(x.b), dataOffset)
+		x.e = add(x.k, bucketCnt*2*goarch.PtrSize)
+
+		if !h.sameSizeGrow() {
+			// Only calculate y pointers if we're growing bigger.
+			// Otherwise GC can see bad pointers.
+			y := &xy[1]
+			y.b = (*bmap)(add(h.buckets, (oldbucket+newbit)*uintptr(t.bucketsize)))
+			y.k = add(unsafe.Pointer(y.b), dataOffset)
+			y.e = add(y.k, bucketCnt*2*goarch.PtrSize)
+		}
+
+		for ; b != nil; b = b.overflow(t) {
+			k := add(unsafe.Pointer(b), dataOffset)
+			e := add(k, bucketCnt*2*goarch.PtrSize)
+			for i := 0; i < bucketCnt; i, k, e = i+1, add(k, 2*goarch.PtrSize), add(e, uintptr(t.elemsize)) {
+				top := b.tophash[i]
+				if isEmpty(top) {
+					b.tophash[i] = evacuatedEmpty
+					continue
+				}
+				if top < minTopHash {
+					throw("bad map state")
+				}
+				var useY uint8
+				if !h.sameSizeGrow() {
+					// Compute hash to make our evacuation decision (whether we need
+					// to send this key/elem to bucket x or bucket y).
+					hash := t.hasher(k, uintptr(h.hash0))
+					if hash&newbit != 0 {
+						useY = 1
+					}
+				}
+
+				b.tophash[i] = evacuatedX + useY // evacuatedX + 1 == evacuatedY, enforced in makemap
+				dst := &xy[useY]                 // evacuation destination
+
+				if dst.i == bucketCnt {
+					dst.b = h.newoverflow(t, dst.b)
+					dst.i = 0
+					dst.k = add(unsafe.Pointer(dst.b), dataOffset)
+					dst.e = add(dst.k, bucketCnt*2*goarch.PtrSize)
+				}
+				dst.b.tophash[dst.i&(bucketCnt-1)] = top // mask dst.i as an optimization, to avoid a bounds check
+
+				// Copy key.
+				*(*string)(dst.k) = *(*string)(k)
+
+				typedmemmove(t.elem, dst.e, e)
+				dst.i++
+				// These updates might push these pointers past the end of the
+				// key or elem arrays.  That's ok, as we have the overflow pointer
+				// at the end of the bucket to protect against pointing past the
+				// end of the bucket.
+				dst.k = add(dst.k, 2*goarch.PtrSize)
+				dst.e = add(dst.e, uintptr(t.elemsize))
+			}
+		}
+		// Unlink the overflow buckets & clear key/elem to help GC.
+		if h.flags&oldIterator == 0 && t.bucket.ptrdata != 0 {
+			b := add(h.oldbuckets, oldbucket*uintptr(t.bucketsize))
+			// Preserve b.tophash because the evacuation
+			// state is maintained there.
+			ptr := add(b, dataOffset)
+			n := uintptr(t.bucketsize) - dataOffset
+			memclrHasPointers(ptr, n)
+		}
+	}
+
+	if oldbucket == h.nevacuate {
+		advanceEvacuationMark(h, t, newbit)
+	}
+}
diff --git a/contrib/go/_std_1.19/src/runtime/mbarrier.go b/contrib/go/_std_1.19/src/runtime/mbarrier.go
new file mode 100644
index 0000000000..c3b45415a9
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/mbarrier.go
@@ -0,0 +1,344 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Garbage collector: write barriers.
+//
+// For the concurrent garbage collector, the Go compiler implements
+// updates to pointer-valued fields that may be in heap objects by
+// emitting calls to write barriers. The main write barrier for
+// individual pointer writes is gcWriteBarrier and is implemented in
+// assembly. This file contains write barrier entry points for bulk
+// operations. See also mwbbuf.go.
+
+package runtime
+
+import (
+	"internal/abi"
+	"internal/goarch"
+	"unsafe"
+)
+
+// Go uses a hybrid barrier that combines a Yuasa-style deletion
+// barrier—which shades the object whose reference is being
+// overwritten—with Dijkstra insertion barrier—which shades the object
+// whose reference is being written. The insertion part of the barrier
+// is necessary while the calling goroutine's stack is grey. In
+// pseudocode, the barrier is:
+//
+//     writePointer(slot, ptr):
+//         shade(*slot)
+//         if current stack is grey:
+//             shade(ptr)
+//         *slot = ptr
+//
+// slot is the destination in Go code.
+// ptr is the value that goes into the slot in Go code.
+//
+// Shade indicates that it has seen a white pointer by adding the referent
+// to wbuf as well as marking it.
+//
+// The two shades and the condition work together to prevent a mutator
+// from hiding an object from the garbage collector:
+//
+// 1. shade(*slot) prevents a mutator from hiding an object by moving
+// the sole pointer to it from the heap to its stack. If it attempts
+// to unlink an object from the heap, this will shade it.
+//
+// 2. shade(ptr) prevents a mutator from hiding an object by moving
+// the sole pointer to it from its stack into a black object in the
+// heap. If it attempts to install the pointer into a black object,
+// this will shade it.
+//
+// 3. Once a goroutine's stack is black, the shade(ptr) becomes
+// unnecessary. shade(ptr) prevents hiding an object by moving it from
+// the stack to the heap, but this requires first having a pointer
+// hidden on the stack. Immediately after a stack is scanned, it only
+// points to shaded objects, so it's not hiding anything, and the
+// shade(*slot) prevents it from hiding any other pointers on its
+// stack.
+//
+// For a detailed description of this barrier and proof of
+// correctness, see https://github.com/golang/proposal/blob/master/design/17503-eliminate-rescan.md
+//
+//
+//
+// Dealing with memory ordering:
+//
+// Both the Yuasa and Dijkstra barriers can be made conditional on the
+// color of the object containing the slot. We chose not to make these
+// conditional because the cost of ensuring that the object holding
+// the slot doesn't concurrently change color without the mutator
+// noticing seems prohibitive.
+//
+// Consider the following example where the mutator writes into
+// a slot and then loads the slot's mark bit while the GC thread
+// writes to the slot's mark bit and then as part of scanning reads
+// the slot.
+//
+// Initially both [slot] and [slotmark] are 0 (nil)
+// Mutator thread          GC thread
+// st [slot], ptr          st [slotmark], 1
+//
+// ld r1, [slotmark]       ld r2, [slot]
+//
+// Without an expensive memory barrier between the st and the ld, the final
+// result on most HW (including 386/amd64) can be r1==r2==0. This is a classic
+// example of what can happen when loads are allowed to be reordered with older
+// stores (avoiding such reorderings lies at the heart of the classic
+// Peterson/Dekker algorithms for mutual exclusion). Rather than require memory
+// barriers, which will slow down both the mutator and the GC, we always grey
+// the ptr object regardless of the slot's color.
+//
+// Another place where we intentionally omit memory barriers is when
+// accessing mheap_.arena_used to check if a pointer points into the
+// heap. On relaxed memory machines, it's possible for a mutator to
+// extend the size of the heap by updating arena_used, allocate an
+// object from this new region, and publish a pointer to that object,
+// but for tracing running on another processor to observe the pointer
+// but use the old value of arena_used. In this case, tracing will not
+// mark the object, even though it's reachable. However, the mutator
+// is guaranteed to execute a write barrier when it publishes the
+// pointer, so it will take care of marking the object. A general
+// consequence of this is that the garbage collector may cache the
+// value of mheap_.arena_used. (See issue #9984.)
+//
+//
+// Stack writes:
+//
+// The compiler omits write barriers for writes to the current frame,
+// but if a stack pointer has been passed down the call stack, the
+// compiler will generate a write barrier for writes through that
+// pointer (because it doesn't know it's not a heap pointer).
+//
+// One might be tempted to ignore the write barrier if slot points
+// into to the stack. Don't do it! Mark termination only re-scans
+// frames that have potentially been active since the concurrent scan,
+// so it depends on write barriers to track changes to pointers in
+// stack frames that have not been active.
+//
+//
+// Global writes:
+//
+// The Go garbage collector requires write barriers when heap pointers
+// are stored in globals. Many garbage collectors ignore writes to
+// globals and instead pick up global -> heap pointers during
+// termination. This increases pause time, so we instead rely on write
+// barriers for writes to globals so that we don't have to rescan
+// global during mark termination.
+//
+//
+// Publication ordering:
+//
+// The write barrier is *pre-publication*, meaning that the write
+// barrier happens prior to the *slot = ptr write that may make ptr
+// reachable by some goroutine that currently cannot reach it.
+//
+//
+// Signal handler pointer writes:
+//
+// In general, the signal handler cannot safely invoke the write
+// barrier because it may run without a P or even during the write
+// barrier.
+//
+// There is exactly one exception: profbuf.go omits a barrier during
+// signal handler profile logging. That's safe only because of the
+// deletion barrier. See profbuf.go for a detailed argument. If we
+// remove the deletion barrier, we'll have to work out a new way to
+// handle the profile logging.
+
+// typedmemmove copies a value of type typ to dst from src.
+// Must be nosplit, see #16026.
+//
+// TODO: Perfect for go:nosplitrec since we can't have a safe point
+// anywhere in the bulk barrier or memmove.
+//
+//go:nosplit
+func typedmemmove(typ *_type, dst, src unsafe.Pointer) {
+	if dst == src {
+		return
+	}
+	if writeBarrier.needed && typ.ptrdata != 0 {
+		bulkBarrierPreWrite(uintptr(dst), uintptr(src), typ.ptrdata)
+	}
+	// There's a race here: if some other goroutine can write to
+	// src, it may change some pointer in src after we've
+	// performed the write barrier but before we perform the
+	// memory copy. This safe because the write performed by that
+	// other goroutine must also be accompanied by a write
+	// barrier, so at worst we've unnecessarily greyed the old
+	// pointer that was in src.
+	memmove(dst, src, typ.size)
+	if writeBarrier.cgo {
+		cgoCheckMemmove(typ, dst, src, 0, typ.size)
+	}
+}
+
+//go:linkname reflect_typedmemmove reflect.typedmemmove
+func reflect_typedmemmove(typ *_type, dst, src unsafe.Pointer) {
+	if raceenabled {
+		raceWriteObjectPC(typ, dst, getcallerpc(), abi.FuncPCABIInternal(reflect_typedmemmove))
+		raceReadObjectPC(typ, src, getcallerpc(), abi.FuncPCABIInternal(reflect_typedmemmove))
+	}
+	if msanenabled {
+		msanwrite(dst, typ.size)
+		msanread(src, typ.size)
+	}
+	if asanenabled {
+		asanwrite(dst, typ.size)
+		asanread(src, typ.size)
+	}
+	typedmemmove(typ, dst, src)
+}
+
+//go:linkname reflectlite_typedmemmove internal/reflectlite.typedmemmove
+func reflectlite_typedmemmove(typ *_type, dst, src unsafe.Pointer) {
+	reflect_typedmemmove(typ, dst, src)
+}
+
+// typedmemmovepartial is like typedmemmove but assumes that
+// dst and src point off bytes into the value and only copies size bytes.
+// off must be a multiple of goarch.PtrSize.
+//
+//go:linkname reflect_typedmemmovepartial reflect.typedmemmovepartial
+func reflect_typedmemmovepartial(typ *_type, dst, src unsafe.Pointer, off, size uintptr) {
+	if writeBarrier.needed && typ.ptrdata > off && size >= goarch.PtrSize {
+		if off&(goarch.PtrSize-1) != 0 {
+			panic("reflect: internal error: misaligned offset")
+		}
+		pwsize := alignDown(size, goarch.PtrSize)
+		if poff := typ.ptrdata - off; pwsize > poff {
+			pwsize = poff
+		}
+		bulkBarrierPreWrite(uintptr(dst), uintptr(src), pwsize)
+	}
+
+	memmove(dst, src, size)
+	if writeBarrier.cgo {
+		cgoCheckMemmove(typ, dst, src, off, size)
+	}
+}
+
+// reflectcallmove is invoked by reflectcall to copy the return values
+// out of the stack and into the heap, invoking the necessary write
+// barriers. dst, src, and size describe the return value area to
+// copy. typ describes the entire frame (not just the return values).
+// typ may be nil, which indicates write barriers are not needed.
+//
+// It must be nosplit and must only call nosplit functions because the
+// stack map of reflectcall is wrong.
+//
+//go:nosplit
+func reflectcallmove(typ *_type, dst, src unsafe.Pointer, size uintptr, regs *abi.RegArgs) {
+	if writeBarrier.needed && typ != nil && typ.ptrdata != 0 && size >= goarch.PtrSize {
+		bulkBarrierPreWrite(uintptr(dst), uintptr(src), size)
+	}
+	memmove(dst, src, size)
+
+	// Move pointers returned in registers to a place where the GC can see them.
+	for i := range regs.Ints {
+		if regs.ReturnIsPtr.Get(i) {
+			regs.Ptrs[i] = unsafe.Pointer(regs.Ints[i])
+		}
+	}
+}
+
+//go:nosplit
+func typedslicecopy(typ *_type, dstPtr unsafe.Pointer, dstLen int, srcPtr unsafe.Pointer, srcLen int) int {
+	n := dstLen
+	if n > srcLen {
+		n = srcLen
+	}
+	if n == 0 {
+		return 0
+	}
+
+	// The compiler emits calls to typedslicecopy before
+	// instrumentation runs, so unlike the other copying and
+	// assignment operations, it's not instrumented in the calling
+	// code and needs its own instrumentation.
+	if raceenabled {
+		callerpc := getcallerpc()
+		pc := abi.FuncPCABIInternal(slicecopy)
+		racewriterangepc(dstPtr, uintptr(n)*typ.size, callerpc, pc)
+		racereadrangepc(srcPtr, uintptr(n)*typ.size, callerpc, pc)
+	}
+	if msanenabled {
+		msanwrite(dstPtr, uintptr(n)*typ.size)
+		msanread(srcPtr, uintptr(n)*typ.size)
+	}
+	if asanenabled {
+		asanwrite(dstPtr, uintptr(n)*typ.size)
+		asanread(srcPtr, uintptr(n)*typ.size)
+	}
+
+	if writeBarrier.cgo {
+		cgoCheckSliceCopy(typ, dstPtr, srcPtr, n)
+	}
+
+	if dstPtr == srcPtr {
+		return n
+	}
+
+	// Note: No point in checking typ.ptrdata here:
+	// compiler only emits calls to typedslicecopy for types with pointers,
+	// and growslice and reflect_typedslicecopy check for pointers
+	// before calling typedslicecopy.
+	size := uintptr(n) * typ.size
+	if writeBarrier.needed {
+		pwsize := size - typ.size + typ.ptrdata
+		bulkBarrierPreWrite(uintptr(dstPtr), uintptr(srcPtr), pwsize)
+	}
+	// See typedmemmove for a discussion of the race between the
+	// barrier and memmove.
+	memmove(dstPtr, srcPtr, size)
+	return n
+}
+
+//go:linkname reflect_typedslicecopy reflect.typedslicecopy
+func reflect_typedslicecopy(elemType *_type, dst, src slice) int {
+	if elemType.ptrdata == 0 {
+		return slicecopy(dst.array, dst.len, src.array, src.len, elemType.size)
+	}
+	return typedslicecopy(elemType, dst.array, dst.len, src.array, src.len)
+}
+
+// typedmemclr clears the typed memory at ptr with type typ. The
+// memory at ptr must already be initialized (and hence in type-safe
+// state). If the memory is being initialized for the first time, see
+// memclrNoHeapPointers.
+//
+// If the caller knows that typ has pointers, it can alternatively
+// call memclrHasPointers.
+//
+//go:nosplit
+func typedmemclr(typ *_type, ptr unsafe.Pointer) {
+	if writeBarrier.needed && typ.ptrdata != 0 {
+		bulkBarrierPreWrite(uintptr(ptr), 0, typ.ptrdata)
+	}
+	memclrNoHeapPointers(ptr, typ.size)
+}
+
+//go:linkname reflect_typedmemclr reflect.typedmemclr
+func reflect_typedmemclr(typ *_type, ptr unsafe.Pointer) {
+	typedmemclr(typ, ptr)
+}
+
+//go:linkname reflect_typedmemclrpartial reflect.typedmemclrpartial
+func reflect_typedmemclrpartial(typ *_type, ptr unsafe.Pointer, off, size uintptr) {
+	if writeBarrier.needed && typ.ptrdata != 0 {
+		bulkBarrierPreWrite(uintptr(ptr), 0, size)
+	}
+	memclrNoHeapPointers(ptr, size)
+}
+
+// memclrHasPointers clears n bytes of typed memory starting at ptr.
+// The caller must ensure that the type of the object at ptr has
+// pointers, usually by checking typ.ptrdata. However, ptr
+// does not have to point to the start of the allocation.
+//
+//go:nosplit
+func memclrHasPointers(ptr unsafe.Pointer, n uintptr) {
+	bulkBarrierPreWrite(uintptr(ptr), 0, n)
+	memclrNoHeapPointers(ptr, n)
+}
diff --git a/contrib/go/_std_1.19/src/runtime/mbitmap.go b/contrib/go/_std_1.19/src/runtime/mbitmap.go
new file mode 100644
index 0000000000..a3a6590d65
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/mbitmap.go
@@ -0,0 +1,2056 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Garbage collector: type and heap bitmaps.
+//
+// Stack, data, and bss bitmaps
+//
+// Stack frames and global variables in the data and bss sections are
+// described by bitmaps with 1 bit per pointer-sized word. A "1" bit
+// means the word is a live pointer to be visited by the GC (referred to
+// as "pointer"). A "0" bit means the word should be ignored by GC
+// (referred to as "scalar", though it could be a dead pointer value).
+//
+// Heap bitmap
+//
+// The heap bitmap comprises 2 bits for each pointer-sized word in the heap,
+// stored in the heapArena metadata backing each heap arena.
+// That is, if ha is the heapArena for the arena starting a start,
+// then ha.bitmap[0] holds the 2-bit entries for the four words start
+// through start+3*ptrSize, ha.bitmap[1] holds the entries for
+// start+4*ptrSize through start+7*ptrSize, and so on.
+//
+// In each 2-bit entry, the lower bit is a pointer/scalar bit, just
+// like in the stack/data bitmaps described above. The upper bit
+// indicates scan/dead: a "1" value ("scan") indicates that there may
+// be pointers in later words of the allocation, and a "0" value
+// ("dead") indicates there are no more pointers in the allocation. If
+// the upper bit is 0, the lower bit must also be 0, and this
+// indicates scanning can ignore the rest of the allocation.
+//
+// The 2-bit entries are split when written into the byte, so that the top half
+// of the byte contains 4 high (scan) bits and the bottom half contains 4 low
+// (pointer) bits. This form allows a copy from the 1-bit to the 4-bit form to
+// keep the pointer bits contiguous, instead of having to space them out.
+//
+// The code makes use of the fact that the zero value for a heap
+// bitmap means scalar/dead. This property must be preserved when
+// modifying the encoding.
+//
+// The bitmap for noscan spans is not maintained. Code must ensure
+// that an object is scannable before consulting its bitmap by
+// checking either the noscan bit in the span or by consulting its
+// type's information.
+
+package runtime
+
+import (
+	"internal/goarch"
+	"runtime/internal/atomic"
+	"runtime/internal/sys"
+	"unsafe"
+)
+
+const (
+	bitPointer = 1 << 0
+	bitScan    = 1 << 4
+
+	heapBitsShift      = 1     // shift offset between successive bitPointer or bitScan entries
+	wordsPerBitmapByte = 8 / 2 // heap words described by one bitmap byte
+
+	// all scan/pointer bits in a byte
+	bitScanAll    = bitScan | bitScan<<heapBitsShift | bitScan<<(2*heapBitsShift) | bitScan<<(3*heapBitsShift)
+	bitPointerAll = bitPointer | bitPointer<<heapBitsShift | bitPointer<<(2*heapBitsShift) | bitPointer<<(3*heapBitsShift)
+)
+
+// addb returns the byte pointer p+n.
+//
+//go:nowritebarrier
+//go:nosplit
+func addb(p *byte, n uintptr) *byte {
+	// Note: wrote out full expression instead of calling add(p, n)
+	// to reduce the number of temporaries generated by the
+	// compiler for this trivial expression during inlining.
+	return (*byte)(unsafe.Pointer(uintptr(unsafe.Pointer(p)) + n))
+}
+
+// subtractb returns the byte pointer p-n.
+//
+//go:nowritebarrier
+//go:nosplit
+func subtractb(p *byte, n uintptr) *byte {
+	// Note: wrote out full expression instead of calling add(p, -n)
+	// to reduce the number of temporaries generated by the
+	// compiler for this trivial expression during inlining.
+	return (*byte)(unsafe.Pointer(uintptr(unsafe.Pointer(p)) - n))
+}
+
+// add1 returns the byte pointer p+1.
+//
+//go:nowritebarrier
+//go:nosplit
+func add1(p *byte) *byte {
+	// Note: wrote out full expression instead of calling addb(p, 1)
+	// to reduce the number of temporaries generated by the
+	// compiler for this trivial expression during inlining.
+	return (*byte)(unsafe.Pointer(uintptr(unsafe.Pointer(p)) + 1))
+}
+
+// subtract1 returns the byte pointer p-1.
+//
+// nosplit because it is used during write barriers and must not be preempted.
+//
+//go:nowritebarrier
+//go:nosplit
+func subtract1(p *byte) *byte {
+	// Note: wrote out full expression instead of calling subtractb(p, 1)
+	// to reduce the number of temporaries generated by the
+	// compiler for this trivial expression during inlining.
+	return (*byte)(unsafe.Pointer(uintptr(unsafe.Pointer(p)) - 1))
+}
+
+// heapBits provides access to the bitmap bits for a single heap word.
+// The methods on heapBits take value receivers so that the compiler
+// can more easily inline calls to those methods and registerize the
+// struct fields independently.
+type heapBits struct {
+	bitp  *uint8
+	shift uint32
+	arena uint32 // Index of heap arena containing bitp
+	last  *uint8 // Last byte arena's bitmap
+}
+
+// Make the compiler check that heapBits.arena is large enough to hold
+// the maximum arena frame number.
+var _ = heapBits{arena: (1<<heapAddrBits)/heapArenaBytes - 1}
+
+// markBits provides access to the mark bit for an object in the heap.
+// bytep points to the byte holding the mark bit.
+// mask is a byte with a single bit set that can be &ed with *bytep
+// to see if the bit has been set.
+// *m.byte&m.mask != 0 indicates the mark bit is set.
+// index can be used along with span information to generate
+// the address of the object in the heap.
+// We maintain one set of mark bits for allocation and one for
+// marking purposes.
+type markBits struct {
+	bytep *uint8
+	mask  uint8
+	index uintptr
+}
+
+//go:nosplit
+func (s *mspan) allocBitsForIndex(allocBitIndex uintptr) markBits {
+	bytep, mask := s.allocBits.bitp(allocBitIndex)
+	return markBits{bytep, mask, allocBitIndex}
+}
+
+// refillAllocCache takes 8 bytes s.allocBits starting at whichByte
+// and negates them so that ctz (count trailing zeros) instructions
+// can be used. It then places these 8 bytes into the cached 64 bit
+// s.allocCache.
+func (s *mspan) refillAllocCache(whichByte uintptr) {
+	bytes := (*[8]uint8)(unsafe.Pointer(s.allocBits.bytep(whichByte)))
+	aCache := uint64(0)
+	aCache |= uint64(bytes[0])
+	aCache |= uint64(bytes[1]) << (1 * 8)
+	aCache |= uint64(bytes[2]) << (2 * 8)
+	aCache |= uint64(bytes[3]) << (3 * 8)
+	aCache |= uint64(bytes[4]) << (4 * 8)
+	aCache |= uint64(bytes[5]) << (5 * 8)
+	aCache |= uint64(bytes[6]) << (6 * 8)
+	aCache |= uint64(bytes[7]) << (7 * 8)
+	s.allocCache = ^aCache
+}
+
+// nextFreeIndex returns the index of the next free object in s at
+// or after s.freeindex.
+// There are hardware instructions that can be used to make this
+// faster if profiling warrants it.
+func (s *mspan) nextFreeIndex() uintptr {
+	sfreeindex := s.freeindex
+	snelems := s.nelems
+	if sfreeindex == snelems {
+		return sfreeindex
+	}
+	if sfreeindex > snelems {
+		throw("s.freeindex > s.nelems")
+	}
+
+	aCache := s.allocCache
+
+	bitIndex := sys.Ctz64(aCache)
+	for bitIndex == 64 {
+		// Move index to start of next cached bits.
+		sfreeindex = (sfreeindex + 64) &^ (64 - 1)
+		if sfreeindex >= snelems {
+			s.freeindex = snelems
+			return snelems
+		}
+		whichByte := sfreeindex / 8
+		// Refill s.allocCache with the next 64 alloc bits.
+		s.refillAllocCache(whichByte)
+		aCache = s.allocCache
+		bitIndex = sys.Ctz64(aCache)
+		// nothing available in cached bits
+		// grab the next 8 bytes and try again.
+	}
+	result := sfreeindex + uintptr(bitIndex)
+	if result >= snelems {
+		s.freeindex = snelems
+		return snelems
+	}
+
+	s.allocCache >>= uint(bitIndex + 1)
+	sfreeindex = result + 1
+
+	if sfreeindex%64 == 0 && sfreeindex != snelems {
+		// We just incremented s.freeindex so it isn't 0.
+		// As each 1 in s.allocCache was encountered and used for allocation
+		// it was shifted away. At this point s.allocCache contains all 0s.
+		// Refill s.allocCache so that it corresponds
+		// to the bits at s.allocBits starting at s.freeindex.
+		whichByte := sfreeindex / 8
+		s.refillAllocCache(whichByte)
+	}
+	s.freeindex = sfreeindex
+	return result
+}
+
+// isFree reports whether the index'th object in s is unallocated.
+//
+// The caller must ensure s.state is mSpanInUse, and there must have
+// been no preemption points since ensuring this (which could allow a
+// GC transition, which would allow the state to change).
+func (s *mspan) isFree(index uintptr) bool {
+	if index < s.freeindex {
+		return false
+	}
+	bytep, mask := s.allocBits.bitp(index)
+	return *bytep&mask == 0
+}
+
+// divideByElemSize returns n/s.elemsize.
+// n must be within [0, s.npages*_PageSize),
+// or may be exactly s.npages*_PageSize
+// if s.elemsize is from sizeclasses.go.
+func (s *mspan) divideByElemSize(n uintptr) uintptr {
+	const doubleCheck = false
+
+	// See explanation in mksizeclasses.go's computeDivMagic.
+	q := uintptr((uint64(n) * uint64(s.divMul)) >> 32)
+
+	if doubleCheck && q != n/s.elemsize {
+		println(n, "/", s.elemsize, "should be", n/s.elemsize, "but got", q)
+		throw("bad magic division")
+	}
+	return q
+}
+
+func (s *mspan) objIndex(p uintptr) uintptr {
+	return s.divideByElemSize(p - s.base())
+}
+
+func markBitsForAddr(p uintptr) markBits {
+	s := spanOf(p)
+	objIndex := s.objIndex(p)
+	return s.markBitsForIndex(objIndex)
+}
+
+func (s *mspan) markBitsForIndex(objIndex uintptr) markBits {
+	bytep, mask := s.gcmarkBits.bitp(objIndex)
+	return markBits{bytep, mask, objIndex}
+}
+
+func (s *mspan) markBitsForBase() markBits {
+	return markBits{(*uint8)(s.gcmarkBits), uint8(1), 0}
+}
+
+// isMarked reports whether mark bit m is set.
+func (m markBits) isMarked() bool {
+	return *m.bytep&m.mask != 0
+}
+
+// setMarked sets the marked bit in the markbits, atomically.
+func (m markBits) setMarked() {
+	// Might be racing with other updates, so use atomic update always.
+	// We used to be clever here and use a non-atomic update in certain
+	// cases, but it's not worth the risk.
+	atomic.Or8(m.bytep, m.mask)
+}
+
+// setMarkedNonAtomic sets the marked bit in the markbits, non-atomically.
+func (m markBits) setMarkedNonAtomic() {
+	*m.bytep |= m.mask
+}
+
+// clearMarked clears the marked bit in the markbits, atomically.
+func (m markBits) clearMarked() {
+	// Might be racing with other updates, so use atomic update always.
+	// We used to be clever here and use a non-atomic update in certain
+	// cases, but it's not worth the risk.
+	atomic.And8(m.bytep, ^m.mask)
+}
+
+// markBitsForSpan returns the markBits for the span base address base.
+func markBitsForSpan(base uintptr) (mbits markBits) {
+	mbits = markBitsForAddr(base)
+	if mbits.mask != 1 {
+		throw("markBitsForSpan: unaligned start")
+	}
+	return mbits
+}
+
+// advance advances the markBits to the next object in the span.
+func (m *markBits) advance() {
+	if m.mask == 1<<7 {
+		m.bytep = (*uint8)(unsafe.Pointer(uintptr(unsafe.Pointer(m.bytep)) + 1))
+		m.mask = 1
+	} else {
+		m.mask = m.mask << 1
+	}
+	m.index++
+}
+
+// heapBitsForAddr returns the heapBits for the address addr.
+// The caller must ensure addr is in an allocated span.
+// In particular, be careful not to point past the end of an object.
+//
+// nosplit because it is used during write barriers and must not be preempted.
+//
+//go:nosplit
+func heapBitsForAddr(addr uintptr) (h heapBits) {
+	// 2 bits per word, 4 pairs per byte, and a mask is hard coded.
+	arena := arenaIndex(addr)
+	ha := mheap_.arenas[arena.l1()][arena.l2()]
+	// The compiler uses a load for nil checking ha, but in this
+	// case we'll almost never hit that cache line again, so it
+	// makes more sense to do a value check.
+	if ha == nil {
+		// addr is not in the heap. Return nil heapBits, which
+		// we expect to crash in the caller.
+		return
+	}
+	h.bitp = &ha.bitmap[(addr/(goarch.PtrSize*4))%heapArenaBitmapBytes]
+	h.shift = uint32((addr / goarch.PtrSize) & 3)
+	h.arena = uint32(arena)
+	h.last = &ha.bitmap[len(ha.bitmap)-1]
+	return
+}
+
+// clobberdeadPtr is a special value that is used by the compiler to
+// clobber dead stack slots, when -clobberdead flag is set.
+const clobberdeadPtr = uintptr(0xdeaddead | 0xdeaddead<<((^uintptr(0)>>63)*32))
+
+// badPointer throws bad pointer in heap panic.
+func badPointer(s *mspan, p, refBase, refOff uintptr) {
+	// Typically this indicates an incorrect use
+	// of unsafe or cgo to store a bad pointer in
+	// the Go heap. It may also indicate a runtime
+	// bug.
+	//
+	// TODO(austin): We could be more aggressive
+	// and detect pointers to unallocated objects
+	// in allocated spans.
+	printlock()
+	print("runtime: pointer ", hex(p))
+	if s != nil {
+		state := s.state.get()
+		if state != mSpanInUse {
+			print(" to unallocated span")
+		} else {
+			print(" to unused region of span")
+		}
+		print(" span.base()=", hex(s.base()), " span.limit=", hex(s.limit), " span.state=", state)
+	}
+	print("\n")
+	if refBase != 0 {
+		print("runtime: found in object at *(", hex(refBase), "+", hex(refOff), ")\n")
+		gcDumpObject("object", refBase, refOff)
+	}
+	getg().m.traceback = 2
+	throw("found bad pointer in Go heap (incorrect use of unsafe or cgo?)")
+}
+
+// findObject returns the base address for the heap object containing
+// the address p, the object's span, and the index of the object in s.
+// If p does not point into a heap object, it returns base == 0.
+//
+// If p points is an invalid heap pointer and debug.invalidptr != 0,
+// findObject panics.
+//
+// refBase and refOff optionally give the base address of the object
+// in which the pointer p was found and the byte offset at which it
+// was found. These are used for error reporting.
+//
+// It is nosplit so it is safe for p to be a pointer to the current goroutine's stack.
+// Since p is a uintptr, it would not be adjusted if the stack were to move.
+//
+//go:nosplit
+func findObject(p, refBase, refOff uintptr) (base uintptr, s *mspan, objIndex uintptr) {
+	s = spanOf(p)
+	// If s is nil, the virtual address has never been part of the heap.
+	// This pointer may be to some mmap'd region, so we allow it.
+	if s == nil {
+		if (GOARCH == "amd64" || GOARCH == "arm64") && p == clobberdeadPtr && debug.invalidptr != 0 {
+			// Crash if clobberdeadPtr is seen. Only on AMD64 and ARM64 for now,
+			// as they are the only platform where compiler's clobberdead mode is
+			// implemented. On these platforms clobberdeadPtr cannot be a valid address.
+			badPointer(s, p, refBase, refOff)
+		}
+		return
+	}
+	// If p is a bad pointer, it may not be in s's bounds.
+	//
+	// Check s.state to synchronize with span initialization
+	// before checking other fields. See also spanOfHeap.
+	if state := s.state.get(); state != mSpanInUse || p < s.base() || p >= s.limit {
+		// Pointers into stacks are also ok, the runtime manages these explicitly.
+		if state == mSpanManual {
+			return
+		}
+		// The following ensures that we are rigorous about what data
+		// structures hold valid pointers.
+		if debug.invalidptr != 0 {
+			badPointer(s, p, refBase, refOff)
+		}
+		return
+	}
+
+	objIndex = s.objIndex(p)
+	base = s.base() + objIndex*s.elemsize
+	return
+}
+
+// verifyNotInHeapPtr reports whether converting the not-in-heap pointer into a unsafe.Pointer is ok.
+//
+//go:linkname reflect_verifyNotInHeapPtr reflect.verifyNotInHeapPtr
+func reflect_verifyNotInHeapPtr(p uintptr) bool {
+	// Conversion to a pointer is ok as long as findObject above does not call badPointer.
+	// Since we're already promised that p doesn't point into the heap, just disallow heap
+	// pointers and the special clobbered pointer.
+	return spanOf(p) == nil && p != clobberdeadPtr
+}
+
+// next returns the heapBits describing the next pointer-sized word in memory.
+// That is, if h describes address p, h.next() describes p+ptrSize.
+// Note that next does not modify h. The caller must record the result.
+//
+// nosplit because it is used during write barriers and must not be preempted.
+//
+//go:nosplit
+func (h heapBits) next() heapBits {
+	if h.shift < 3*heapBitsShift {
+		h.shift += heapBitsShift
+	} else if h.bitp != h.last {
+		h.bitp, h.shift = add1(h.bitp), 0
+	} else {
+		// Move to the next arena.
+		return h.nextArena()
+	}
+	return h
+}
+
+// nextArena advances h to the beginning of the next heap arena.
+//
+// This is a slow-path helper to next. gc's inliner knows that
+// heapBits.next can be inlined even though it calls this. This is
+// marked noinline so it doesn't get inlined into next and cause next
+// to be too big to inline.
+//
+//go:nosplit
+//go:noinline
+func (h heapBits) nextArena() heapBits {
+	h.arena++
+	ai := arenaIdx(h.arena)
+	l2 := mheap_.arenas[ai.l1()]
+	if l2 == nil {
+		// We just passed the end of the object, which
+		// was also the end of the heap. Poison h. It
+		// should never be dereferenced at this point.
+		return heapBits{}
+	}
+	ha := l2[ai.l2()]
+	if ha == nil {
+		return heapBits{}
+	}
+	h.bitp, h.shift = &ha.bitmap[0], 0
+	h.last = &ha.bitmap[len(ha.bitmap)-1]
+	return h
+}
+
+// forward returns the heapBits describing n pointer-sized words ahead of h in memory.
+// That is, if h describes address p, h.forward(n) describes p+n*ptrSize.
+// h.forward(1) is equivalent to h.next(), just slower.
+// Note that forward does not modify h. The caller must record the result.
+// bits returns the heap bits for the current word.
+//
+//go:nosplit
+func (h heapBits) forward(n uintptr) heapBits {
+	n += uintptr(h.shift) / heapBitsShift
+	nbitp := uintptr(unsafe.Pointer(h.bitp)) + n/4
+	h.shift = uint32(n%4) * heapBitsShift
+	if nbitp <= uintptr(unsafe.Pointer(h.last)) {
+		h.bitp = (*uint8)(unsafe.Pointer(nbitp))
+		return h
+	}
+
+	// We're in a new heap arena.
+	past := nbitp - (uintptr(unsafe.Pointer(h.last)) + 1)
+	h.arena += 1 + uint32(past/heapArenaBitmapBytes)
+	ai := arenaIdx(h.arena)
+	if l2 := mheap_.arenas[ai.l1()]; l2 != nil && l2[ai.l2()] != nil {
+		a := l2[ai.l2()]
+		h.bitp = &a.bitmap[past%heapArenaBitmapBytes]
+		h.last = &a.bitmap[len(a.bitmap)-1]
+	} else {
+		h.bitp, h.last = nil, nil
+	}
+	return h
+}
+
+// forwardOrBoundary is like forward, but stops at boundaries between
+// contiguous sections of the bitmap. It returns the number of words
+// advanced over, which will be <= n.
+func (h heapBits) forwardOrBoundary(n uintptr) (heapBits, uintptr) {
+	maxn := 4 * ((uintptr(unsafe.Pointer(h.last)) + 1) - uintptr(unsafe.Pointer(h.bitp)))
+	if n > maxn {
+		n = maxn
+	}
+	return h.forward(n), n
+}
+
+// The caller can test morePointers and isPointer by &-ing with bitScan and bitPointer.
+// The result includes in its higher bits the bits for subsequent words
+// described by the same bitmap byte.
+//
+// nosplit because it is used during write barriers and must not be preempted.
+//
+//go:nosplit
+func (h heapBits) bits() uint32 {
+	// The (shift & 31) eliminates a test and conditional branch
+	// from the generated code.
+	return uint32(*h.bitp) >> (h.shift & 31)
+}
+
+// morePointers reports whether this word and all remaining words in this object
+// are scalars.
+// h must not describe the second word of the object.
+func (h heapBits) morePointers() bool {
+	return h.bits()&bitScan != 0
+}
+
+// isPointer reports whether the heap bits describe a pointer word.
+//
+// nosplit because it is used during write barriers and must not be preempted.
+//
+//go:nosplit
+func (h heapBits) isPointer() bool {
+	return h.bits()&bitPointer != 0
+}
+
+// bulkBarrierPreWrite executes a write barrier
+// for every pointer slot in the memory range [src, src+size),
+// using pointer/scalar information from [dst, dst+size).
+// This executes the write barriers necessary before a memmove.
+// src, dst, and size must be pointer-aligned.
+// The range [dst, dst+size) must lie within a single object.
+// It does not perform the actual writes.
+//
+// As a special case, src == 0 indicates that this is being used for a
+// memclr. bulkBarrierPreWrite will pass 0 for the src of each write
+// barrier.
+//
+// Callers should call bulkBarrierPreWrite immediately before
+// calling memmove(dst, src, size). This function is marked nosplit
+// to avoid being preempted; the GC must not stop the goroutine
+// between the memmove and the execution of the barriers.
+// The caller is also responsible for cgo pointer checks if this
+// may be writing Go pointers into non-Go memory.
+//
+// The pointer bitmap is not maintained for allocations containing
+// no pointers at all; any caller of bulkBarrierPreWrite must first
+// make sure the underlying allocation contains pointers, usually
+// by checking typ.ptrdata.
+//
+// Callers must perform cgo checks if writeBarrier.cgo.
+//
+//go:nosplit
+func bulkBarrierPreWrite(dst, src, size uintptr) {
+	if (dst|src|size)&(goarch.PtrSize-1) != 0 {
+		throw("bulkBarrierPreWrite: unaligned arguments")
+	}
+	if !writeBarrier.needed {
+		return
+	}
+	if s := spanOf(dst); s == nil {
+		// If dst is a global, use the data or BSS bitmaps to
+		// execute write barriers.
+		for _, datap := range activeModules() {
+			if datap.data <= dst && dst < datap.edata {
+				bulkBarrierBitmap(dst, src, size, dst-datap.data, datap.gcdatamask.bytedata)
+				return
+			}
+		}
+		for _, datap := range activeModules() {
+			if datap.bss <= dst && dst < datap.ebss {
+				bulkBarrierBitmap(dst, src, size, dst-datap.bss, datap.gcbssmask.bytedata)
+				return
+			}
+		}
+		return
+	} else if s.state.get() != mSpanInUse || dst < s.base() || s.limit <= dst {
+		// dst was heap memory at some point, but isn't now.
+		// It can't be a global. It must be either our stack,
+		// or in the case of direct channel sends, it could be
+		// another stack. Either way, no need for barriers.
+		// This will also catch if dst is in a freed span,
+		// though that should never have.
+		return
+	}
+
+	buf := &getg().m.p.ptr().wbBuf
+	h := heapBitsForAddr(dst)
+	if src == 0 {
+		for i := uintptr(0); i < size; i += goarch.PtrSize {
+			if h.isPointer() {
+				dstx := (*uintptr)(unsafe.Pointer(dst + i))
+				if !buf.putFast(*dstx, 0) {
+					wbBufFlush(nil, 0)
+				}
+			}
+			h = h.next()
+		}
+	} else {
+		for i := uintptr(0); i < size; i += goarch.PtrSize {
+			if h.isPointer() {
+				dstx := (*uintptr)(unsafe.Pointer(dst + i))
+				srcx := (*uintptr)(unsafe.Pointer(src + i))
+				if !buf.putFast(*dstx, *srcx) {
+					wbBufFlush(nil, 0)
+				}
+			}
+			h = h.next()
+		}
+	}
+}
+
+// bulkBarrierPreWriteSrcOnly is like bulkBarrierPreWrite but
+// does not execute write barriers for [dst, dst+size).
+//
+// In addition to the requirements of bulkBarrierPreWrite
+// callers need to ensure [dst, dst+size) is zeroed.
+//
+// This is used for special cases where e.g. dst was just
+// created and zeroed with malloc.
+//
+//go:nosplit
+func bulkBarrierPreWriteSrcOnly(dst, src, size uintptr) {
+	if (dst|src|size)&(goarch.PtrSize-1) != 0 {
+		throw("bulkBarrierPreWrite: unaligned arguments")
+	}
+	if !writeBarrier.needed {
+		return
+	}
+	buf := &getg().m.p.ptr().wbBuf
+	h := heapBitsForAddr(dst)
+	for i := uintptr(0); i < size; i += goarch.PtrSize {
+		if h.isPointer() {
+			srcx := (*uintptr)(unsafe.Pointer(src + i))
+			if !buf.putFast(0, *srcx) {
+				wbBufFlush(nil, 0)
+			}
+		}
+		h = h.next()
+	}
+}
+
+// bulkBarrierBitmap executes write barriers for copying from [src,
+// src+size) to [dst, dst+size) using a 1-bit pointer bitmap. src is
+// assumed to start maskOffset bytes into the data covered by the
+// bitmap in bits (which may not be a multiple of 8).
+//
+// This is used by bulkBarrierPreWrite for writes to data and BSS.
+//
+//go:nosplit
+func bulkBarrierBitmap(dst, src, size, maskOffset uintptr, bits *uint8) {
+	word := maskOffset / goarch.PtrSize
+	bits = addb(bits, word/8)
+	mask := uint8(1) << (word % 8)
+
+	buf := &getg().m.p.ptr().wbBuf
+	for i := uintptr(0); i < size; i += goarch.PtrSize {
+		if mask == 0 {
+			bits = addb(bits, 1)
+			if *bits == 0 {
+				// Skip 8 words.
+				i += 7 * goarch.PtrSize
+				continue
+			}
+			mask = 1
+		}
+		if *bits&mask != 0 {
+			dstx := (*uintptr)(unsafe.Pointer(dst + i))
+			if src == 0 {
+				if !buf.putFast(*dstx, 0) {
+					wbBufFlush(nil, 0)
+				}
+			} else {
+				srcx := (*uintptr)(unsafe.Pointer(src + i))
+				if !buf.putFast(*dstx, *srcx) {
+					wbBufFlush(nil, 0)
+				}
+			}
+		}
+		mask <<= 1
+	}
+}
+
+// typeBitsBulkBarrier executes a write barrier for every
+// pointer that would be copied from [src, src+size) to [dst,
+// dst+size) by a memmove using the type bitmap to locate those
+// pointer slots.
+//
+// The type typ must correspond exactly to [src, src+size) and [dst, dst+size).
+// dst, src, and size must be pointer-aligned.
+// The type typ must have a plain bitmap, not a GC program.
+// The only use of this function is in channel sends, and the
+// 64 kB channel element limit takes care of this for us.
+//
+// Must not be preempted because it typically runs right before memmove,
+// and the GC must observe them as an atomic action.
+//
+// Callers must perform cgo checks if writeBarrier.cgo.
+//
+//go:nosplit
+func typeBitsBulkBarrier(typ *_type, dst, src, size uintptr) {
+	if typ == nil {
+		throw("runtime: typeBitsBulkBarrier without type")
+	}
+	if typ.size != size {
+		println("runtime: typeBitsBulkBarrier with type ", typ.string(), " of size ", typ.size, " but memory size", size)
+		throw("runtime: invalid typeBitsBulkBarrier")
+	}
+	if typ.kind&kindGCProg != 0 {
+		println("runtime: typeBitsBulkBarrier with type ", typ.string(), " with GC prog")
+		throw("runtime: invalid typeBitsBulkBarrier")
+	}
+	if !writeBarrier.needed {
+		return
+	}
+	ptrmask := typ.gcdata
+	buf := &getg().m.p.ptr().wbBuf
+	var bits uint32
+	for i := uintptr(0); i < typ.ptrdata; i += goarch.PtrSize {
+		if i&(goarch.PtrSize*8-1) == 0 {
+			bits = uint32(*ptrmask)
+			ptrmask = addb(ptrmask, 1)
+		} else {
+			bits = bits >> 1
+		}
+		if bits&1 != 0 {
+			dstx := (*uintptr)(unsafe.Pointer(dst + i))
+			srcx := (*uintptr)(unsafe.Pointer(src + i))
+			if !buf.putFast(*dstx, *srcx) {
+				wbBufFlush(nil, 0)
+			}
+		}
+	}
+}
+
+// The methods operating on spans all require that h has been returned
+// by heapBitsForSpan and that size, n, total are the span layout description
+// returned by the mspan's layout method.
+// If total > size*n, it means that there is extra leftover memory in the span,
+// usually due to rounding.
+//
+// TODO(rsc): Perhaps introduce a different heapBitsSpan type.
+
+// initSpan initializes the heap bitmap for a span.
+// If this is a span of pointer-sized objects, it initializes all
+// words to pointer/scan.
+// Otherwise, it initializes all words to scalar/dead.
+func (h heapBits) initSpan(s *mspan) {
+	// Clear bits corresponding to objects.
+	nw := (s.npages << _PageShift) / goarch.PtrSize
+	if nw%wordsPerBitmapByte != 0 {
+		throw("initSpan: unaligned length")
+	}
+	if h.shift != 0 {
+		throw("initSpan: unaligned base")
+	}
+	isPtrs := goarch.PtrSize == 8 && s.elemsize == goarch.PtrSize
+	for nw > 0 {
+		hNext, anw := h.forwardOrBoundary(nw)
+		nbyte := anw / wordsPerBitmapByte
+		if isPtrs {
+			bitp := h.bitp
+			for i := uintptr(0); i < nbyte; i++ {
+				*bitp = bitPointerAll | bitScanAll
+				bitp = add1(bitp)
+			}
+		} else {
+			memclrNoHeapPointers(unsafe.Pointer(h.bitp), nbyte)
+		}
+		h = hNext
+		nw -= anw
+	}
+}
+
+// countAlloc returns the number of objects allocated in span s by
+// scanning the allocation bitmap.
+func (s *mspan) countAlloc() int {
+	count := 0
+	bytes := divRoundUp(s.nelems, 8)
+	// Iterate over each 8-byte chunk and count allocations
+	// with an intrinsic. Note that newMarkBits guarantees that
+	// gcmarkBits will be 8-byte aligned, so we don't have to
+	// worry about edge cases, irrelevant bits will simply be zero.
+	for i := uintptr(0); i < bytes; i += 8 {
+		// Extract 64 bits from the byte pointer and get a OnesCount.
+		// Note that the unsafe cast here doesn't preserve endianness,
+		// but that's OK. We only care about how many bits are 1, not
+		// about the order we discover them in.
+		mrkBits := *(*uint64)(unsafe.Pointer(s.gcmarkBits.bytep(i)))
+		count += sys.OnesCount64(mrkBits)
+	}
+	return count
+}
+
+// heapBitsSetType records that the new allocation [x, x+size)
+// holds in [x, x+dataSize) one or more values of type typ.
+// (The number of values is given by dataSize / typ.size.)
+// If dataSize < size, the fragment [x+dataSize, x+size) is
+// recorded as non-pointer data.
+// It is known that the type has pointers somewhere;
+// malloc does not call heapBitsSetType when there are no pointers,
+// because all free objects are marked as noscan during
+// heapBitsSweepSpan.
+//
+// There can only be one allocation from a given span active at a time,
+// and the bitmap for a span always falls on byte boundaries,
+// so there are no write-write races for access to the heap bitmap.
+// Hence, heapBitsSetType can access the bitmap without atomics.
+//
+// There can be read-write races between heapBitsSetType and things
+// that read the heap bitmap like scanobject. However, since
+// heapBitsSetType is only used for objects that have not yet been
+// made reachable, readers will ignore bits being modified by this
+// function. This does mean this function cannot transiently modify
+// bits that belong to neighboring objects. Also, on weakly-ordered
+// machines, callers must execute a store/store (publication) barrier
+// between calling this function and making the object reachable.
+func heapBitsSetType(x, size, dataSize uintptr, typ *_type) {
+	const doubleCheck = false // slow but helpful; enable to test modifications to this code
+
+	const (
+		mask1 = bitPointer | bitScan                        // 00010001
+		mask2 = bitPointer | bitScan | mask1<<heapBitsShift // 00110011
+		mask3 = bitPointer | bitScan | mask2<<heapBitsShift // 01110111
+	)
+
+	// dataSize is always size rounded up to the next malloc size class,
+	// except in the case of allocating a defer block, in which case
+	// size is sizeof(_defer{}) (at least 6 words) and dataSize may be
+	// arbitrarily larger.
+	//
+	// The checks for size == goarch.PtrSize and size == 2*goarch.PtrSize can therefore
+	// assume that dataSize == size without checking it explicitly.
+
+	if goarch.PtrSize == 8 && size == goarch.PtrSize {
+		// It's one word and it has pointers, it must be a pointer.
+		// Since all allocated one-word objects are pointers
+		// (non-pointers are aggregated into tinySize allocations),
+		// initSpan sets the pointer bits for us. Nothing to do here.
+		if doubleCheck {
+			h := heapBitsForAddr(x)
+			if !h.isPointer() {
+				throw("heapBitsSetType: pointer bit missing")
+			}
+			if !h.morePointers() {
+				throw("heapBitsSetType: scan bit missing")
+			}
+		}
+		return
+	}
+
+	h := heapBitsForAddr(x)
+	ptrmask := typ.gcdata // start of 1-bit pointer mask (or GC program, handled below)
+
+	// 2-word objects only have 4 bitmap bits and 3-word objects only have 6 bitmap bits.
+	// Therefore, these objects share a heap bitmap byte with the objects next to them.
+	// These are called out as a special case primarily so the code below can assume all
+	// objects are at least 4 words long and that their bitmaps start either at the beginning
+	// of a bitmap byte, or half-way in (h.shift of 0 and 2 respectively).
+
+	if size == 2*goarch.PtrSize {
+		if typ.size == goarch.PtrSize {
+			// We're allocating a block big enough to hold two pointers.
+			// On 64-bit, that means the actual object must be two pointers,
+			// or else we'd have used the one-pointer-sized block.
+			// On 32-bit, however, this is the 8-byte block, the smallest one.
+			// So it could be that we're allocating one pointer and this was
+			// just the smallest block available. Distinguish by checking dataSize.
+			// (In general the number of instances of typ being allocated is
+			// dataSize/typ.size.)
+			if goarch.PtrSize == 4 && dataSize == goarch.PtrSize {
+				// 1 pointer object. On 32-bit machines clear the bit for the
+				// unused second word.
+				*h.bitp &^= (bitPointer | bitScan | (bitPointer|bitScan)<<heapBitsShift) << h.shift
+				*h.bitp |= (bitPointer | bitScan) << h.shift
+			} else {
+				// 2-element array of pointer.
+				*h.bitp |= (bitPointer | bitScan | (bitPointer|bitScan)<<heapBitsShift) << h.shift
+			}
+			return
+		}
+		// Otherwise typ.size must be 2*goarch.PtrSize,
+		// and typ.kind&kindGCProg == 0.
+		if doubleCheck {
+			if typ.size != 2*goarch.PtrSize || typ.kind&kindGCProg != 0 {
+				print("runtime: heapBitsSetType size=", size, " but typ.size=", typ.size, " gcprog=", typ.kind&kindGCProg != 0, "\n")
+				throw("heapBitsSetType")
+			}
+		}
+		b := uint32(*ptrmask)
+		hb := b & 3
+		hb |= bitScanAll & ((bitScan << (typ.ptrdata / goarch.PtrSize)) - 1)
+		// Clear the bits for this object so we can set the
+		// appropriate ones.
+		*h.bitp &^= (bitPointer | bitScan | ((bitPointer | bitScan) << heapBitsShift)) << h.shift
+		*h.bitp |= uint8(hb << h.shift)
+		return
+	} else if size == 3*goarch.PtrSize {
+		b := uint8(*ptrmask)
+		if doubleCheck {
+			if b == 0 {
+				println("runtime: invalid type ", typ.string())
+				throw("heapBitsSetType: called with non-pointer type")
+			}
+			if goarch.PtrSize != 8 {
+				throw("heapBitsSetType: unexpected 3 pointer wide size class on 32 bit")
+			}
+			if typ.kind&kindGCProg != 0 {
+				throw("heapBitsSetType: unexpected GC prog for 3 pointer wide size class")
+			}
+			if typ.size == 2*goarch.PtrSize {
+				print("runtime: heapBitsSetType size=", size, " but typ.size=", typ.size, "\n")
+				throw("heapBitsSetType: inconsistent object sizes")
+			}
+		}
+		if typ.size == goarch.PtrSize {
+			// The type contains a pointer otherwise heapBitsSetType wouldn't have been called.
+			// Since the type is only 1 pointer wide and contains a pointer, its gcdata must be exactly 1.
+			if doubleCheck && *typ.gcdata != 1 {
+				print("runtime: heapBitsSetType size=", size, " typ.size=", typ.size, "but *typ.gcdata", *typ.gcdata, "\n")
+				throw("heapBitsSetType: unexpected gcdata for 1 pointer wide type size in 3 pointer wide size class")
+			}
+			// 3 element array of pointers. Unrolling ptrmask 3 times into p yields 00000111.
+			b = 7
+		}
+
+		hb := b & 7
+		// Set bitScan bits for all pointers.
+		hb |= hb << wordsPerBitmapByte
+		// First bitScan bit is always set since the type contains pointers.
+		hb |= bitScan
+		// Second bitScan bit needs to also be set if the third bitScan bit is set.
+		hb |= hb & (bitScan << (2 * heapBitsShift)) >> 1
+
+		// For h.shift > 1 heap bits cross a byte boundary and need to be written part
+		// to h.bitp and part to the next h.bitp.
+		switch h.shift {
+		case 0:
+			*h.bitp &^= mask3 << 0
+			*h.bitp |= hb << 0
+		case 1:
+			*h.bitp &^= mask3 << 1
+			*h.bitp |= hb << 1
+		case 2:
+			*h.bitp &^= mask2 << 2
+			*h.bitp |= (hb & mask2) << 2
+			// Two words written to the first byte.
+			// Advance two words to get to the next byte.
+			h = h.next().next()
+			*h.bitp &^= mask1
+			*h.bitp |= (hb >> 2) & mask1
+		case 3:
+			*h.bitp &^= mask1 << 3
+			*h.bitp |= (hb & mask1) << 3
+			// One word written to the first byte.
+			// Advance one word to get to the next byte.
+			h = h.next()
+			*h.bitp &^= mask2
+			*h.bitp |= (hb >> 1) & mask2
+		}
+		return
+	}
+
+	// Copy from 1-bit ptrmask into 2-bit bitmap.
+	// The basic approach is to use a single uintptr as a bit buffer,
+	// alternating between reloading the buffer and writing bitmap bytes.
+	// In general, one load can supply two bitmap byte writes.
+	// This is a lot of lines of code, but it compiles into relatively few
+	// machine instructions.
+
+	outOfPlace := false
+	if arenaIndex(x+size-1) != arenaIdx(h.arena) || (doubleCheck && fastrandn(2) == 0) {
+		// This object spans heap arenas, so the bitmap may be
+		// discontiguous. Unroll it into the object instead
+		// and then copy it out.
+		//
+		// In doubleCheck mode, we randomly do this anyway to
+		// stress test the bitmap copying path.
+		outOfPlace = true
+		h.bitp = (*uint8)(unsafe.Pointer(x))
+		h.last = nil
+	}
+
+	var (
+		// Ptrmask input.
+		p     *byte   // last ptrmask byte read
+		b     uintptr // ptrmask bits already loaded
+		nb    uintptr // number of bits in b at next read
+		endp  *byte   // final ptrmask byte to read (then repeat)
+		endnb uintptr // number of valid bits in *endp
+		pbits uintptr // alternate source of bits
+
+		// Heap bitmap output.
+		w     uintptr // words processed
+		nw    uintptr // number of words to process
+		hbitp *byte   // next heap bitmap byte to write
+		hb    uintptr // bits being prepared for *hbitp
+	)
+
+	hbitp = h.bitp
+
+	// Handle GC program. Delayed until this part of the code
+	// so that we can use the same double-checking mechanism
+	// as the 1-bit case. Nothing above could have encountered
+	// GC programs: the cases were all too small.
+	if typ.kind&kindGCProg != 0 {
+		heapBitsSetTypeGCProg(h, typ.ptrdata, typ.size, dataSize, size, addb(typ.gcdata, 4))
+		if doubleCheck {
+			// Double-check the heap bits written by GC program
+			// by running the GC program to create a 1-bit pointer mask
+			// and then jumping to the double-check code below.
+			// This doesn't catch bugs shared between the 1-bit and 4-bit
+			// GC program execution, but it does catch mistakes specific
+			// to just one of those and bugs in heapBitsSetTypeGCProg's
+			// implementation of arrays.
+			lock(&debugPtrmask.lock)
+			if debugPtrmask.data == nil {
+				debugPtrmask.data = (*byte)(persistentalloc(1<<20, 1, &memstats.other_sys))
+			}
+			ptrmask = debugPtrmask.data
+			runGCProg(addb(typ.gcdata, 4), nil, ptrmask, 1)
+		}
+		goto Phase4
+	}
+
+	// Note about sizes:
+	//
+	// typ.size is the number of words in the object,
+	// and typ.ptrdata is the number of words in the prefix
+	// of the object that contains pointers. That is, the final
+	// typ.size - typ.ptrdata words contain no pointers.
+	// This allows optimization of a common pattern where
+	// an object has a small header followed by a large scalar
+	// buffer. If we know the pointers are over, we don't have
+	// to scan the buffer's heap bitmap at all.
+	// The 1-bit ptrmasks are sized to contain only bits for
+	// the typ.ptrdata prefix, zero padded out to a full byte
+	// of bitmap. This code sets nw (below) so that heap bitmap
+	// bits are only written for the typ.ptrdata prefix; if there is
+	// more room in the allocated object, the next heap bitmap
+	// entry is a 00, indicating that there are no more pointers
+	// to scan. So only the ptrmask for the ptrdata bytes is needed.
+	//
+	// Replicated copies are not as nice: if there is an array of
+	// objects with scalar tails, all but the last tail does have to
+	// be initialized, because there is no way to say "skip forward".
+	// However, because of the possibility of a repeated type with
+	// size not a multiple of 4 pointers (one heap bitmap byte),
+	// the code already must handle the last ptrmask byte specially
+	// by treating it as containing only the bits for endnb pointers,
+	// where endnb <= 4. We represent large scalar tails that must
+	// be expanded in the replication by setting endnb larger than 4.
+	// This will have the effect of reading many bits out of b,
+	// but once the real bits are shifted out, b will supply as many
+	// zero bits as we try to read, which is exactly what we need.
+
+	p = ptrmask
+	if typ.size < dataSize {
+		// Filling in bits for an array of typ.
+		// Set up for repetition of ptrmask during main loop.
+		// Note that ptrmask describes only a prefix of
+		const maxBits = goarch.PtrSize*8 - 7
+		if typ.ptrdata/goarch.PtrSize <= maxBits {
+			// Entire ptrmask fits in uintptr with room for a byte fragment.
+			// Load into pbits and never read from ptrmask again.
+			// This is especially important when the ptrmask has
+			// fewer than 8 bits in it; otherwise the reload in the middle
+			// of the Phase 2 loop would itself need to loop to gather
+			// at least 8 bits.
+
+			// Accumulate ptrmask into b.
+			// ptrmask is sized to describe only typ.ptrdata, but we record
+			// it as describing typ.size bytes, since all the high bits are zero.
+			nb = typ.ptrdata / goarch.PtrSize
+			for i := uintptr(0); i < nb; i += 8 {
+				b |= uintptr(*p) << i
+				p = add1(p)
+			}
+			nb = typ.size / goarch.PtrSize
+
+			// Replicate ptrmask to fill entire pbits uintptr.
+			// Doubling and truncating is fewer steps than
+			// iterating by nb each time. (nb could be 1.)
+			// Since we loaded typ.ptrdata/goarch.PtrSize bits
+			// but are pretending to have typ.size/goarch.PtrSize,
+			// there might be no replication necessary/possible.
+			pbits = b
+			endnb = nb
+			if nb+nb <= maxBits {
+				for endnb <= goarch.PtrSize*8 {
+					pbits |= pbits << endnb
+					endnb += endnb
+				}
+				// Truncate to a multiple of original ptrmask.
+				// Because nb+nb <= maxBits, nb fits in a byte.
+				// Byte division is cheaper than uintptr division.
+				endnb = uintptr(maxBits/byte(nb)) * nb
+				pbits &= 1<<endnb - 1
+				b = pbits
+				nb = endnb
+			}
+
+			// Clear p and endp as sentinel for using pbits.
+			// Checked during Phase 2 loop.
+			p = nil
+			endp = nil
+		} else {
+			// Ptrmask is larger. Read it multiple times.
+			n := (typ.ptrdata/goarch.PtrSize+7)/8 - 1
+			endp = addb(ptrmask, n)
+			endnb = typ.size/goarch.PtrSize - n*8
+		}
+	}
+	if p != nil {
+		b = uintptr(*p)
+		p = add1(p)
+		nb = 8
+	}
+
+	if typ.size == dataSize {
+		// Single entry: can stop once we reach the non-pointer data.
+		nw = typ.ptrdata / goarch.PtrSize
+	} else {
+		// Repeated instances of typ in an array.
+		// Have to process first N-1 entries in full, but can stop
+		// once we reach the non-pointer data in the final entry.
+		nw = ((dataSize/typ.size-1)*typ.size + typ.ptrdata) / goarch.PtrSize
+	}
+	if nw == 0 {
+		// No pointers! Caller was supposed to check.
+		println("runtime: invalid type ", typ.string())
+		throw("heapBitsSetType: called with non-pointer type")
+		return
+	}
+
+	// Phase 1: Special case for leading byte (shift==0) or half-byte (shift==2).
+	// The leading byte is special because it contains the bits for word 1,
+	// which does not have the scan bit set.
+	// The leading half-byte is special because it's a half a byte,
+	// so we have to be careful with the bits already there.
+	switch {
+	default:
+		throw("heapBitsSetType: unexpected shift")
+
+	case h.shift == 0:
+		// Ptrmask and heap bitmap are aligned.
+		//
+		// This is a fast path for small objects.
+		//
+		// The first byte we write out covers the first four
+		// words of the object. The scan/dead bit on the first
+		// word must be set to scan since there are pointers
+		// somewhere in the object.
+		// In all following words, we set the scan/dead
+		// appropriately to indicate that the object continues
+		// to the next 2-bit entry in the bitmap.
+		//
+		// We set four bits at a time here, but if the object
+		// is fewer than four words, phase 3 will clear
+		// unnecessary bits.
+		hb = b & bitPointerAll
+		hb |= bitScanAll
+		if w += 4; w >= nw {
+			goto Phase3
+		}
+		*hbitp = uint8(hb)
+		hbitp = add1(hbitp)
+		b >>= 4
+		nb -= 4
+
+	case h.shift == 2:
+		// Ptrmask and heap bitmap are misaligned.
+		//
+		// On 32 bit architectures only the 6-word object that corresponds
+		// to a 24 bytes size class can start with h.shift of 2 here since
+		// all other non 16 byte aligned size classes have been handled by
+		// special code paths at the beginning of heapBitsSetType on 32 bit.
+		//
+		// Many size classes are only 16 byte aligned. On 64 bit architectures
+		// this results in a heap bitmap position starting with a h.shift of 2.
+		//
+		// The bits for the first two words are in a byte shared
+		// with another object, so we must be careful with the bits
+		// already there.
+		//
+		// We took care of 1-word, 2-word, and 3-word objects above,
+		// so this is at least a 6-word object.
+		hb = (b & (bitPointer | bitPointer<<heapBitsShift)) << (2 * heapBitsShift)
+		hb |= bitScan << (2 * heapBitsShift)
+		if nw > 1 {
+			hb |= bitScan << (3 * heapBitsShift)
+		}
+		b >>= 2
+		nb -= 2
+		*hbitp &^= uint8((bitPointer | bitScan | ((bitPointer | bitScan) << heapBitsShift)) << (2 * heapBitsShift))
+		*hbitp |= uint8(hb)
+		hbitp = add1(hbitp)
+		if w += 2; w >= nw {
+			// We know that there is more data, because we handled 2-word and 3-word objects above.
+			// This must be at least a 6-word object. If we're out of pointer words,
+			// mark no scan in next bitmap byte and finish.
+			hb = 0
+			w += 4
+			goto Phase3
+		}
+	}
+
+	// Phase 2: Full bytes in bitmap, up to but not including write to last byte (full or partial) in bitmap.
+	// The loop computes the bits for that last write but does not execute the write;
+	// it leaves the bits in hb for processing by phase 3.
+	// To avoid repeated adjustment of nb, we subtract out the 4 bits we're going to
+	// use in the first half of the loop right now, and then we only adjust nb explicitly
+	// if the 8 bits used by each iteration isn't balanced by 8 bits loaded mid-loop.
+	nb -= 4
+	for {
+		// Emit bitmap byte.
+		// b has at least nb+4 bits, with one exception:
+		// if w+4 >= nw, then b has only nw-w bits,
+		// but we'll stop at the break and then truncate
+		// appropriately in Phase 3.
+		hb = b & bitPointerAll
+		hb |= bitScanAll
+		if w += 4; w >= nw {
+			break
+		}
+		*hbitp = uint8(hb)
+		hbitp = add1(hbitp)
+		b >>= 4
+
+		// Load more bits. b has nb right now.
+		if p != endp {
+			// Fast path: keep reading from ptrmask.
+			// nb unmodified: we just loaded 8 bits,
+			// and the next iteration will consume 8 bits,
+			// leaving us with the same nb the next time we're here.
+			if nb < 8 {
+				b |= uintptr(*p) << nb
+				p = add1(p)
+			} else {
+				// Reduce the number of bits in b.
+				// This is important if we skipped
+				// over a scalar tail, since nb could
+				// be larger than the bit width of b.
+				nb -= 8
+			}
+		} else if p == nil {
+			// Almost as fast path: track bit count and refill from pbits.
+			// For short repetitions.
+			if nb < 8 {
+				b |= pbits << nb
+				nb += endnb
+			}
+			nb -= 8 // for next iteration
+		} else {
+			// Slow path: reached end of ptrmask.
+			// Process final partial byte and rewind to start.
+			b |= uintptr(*p) << nb
+			nb += endnb
+			if nb < 8 {
+				b |= uintptr(*ptrmask) << nb
+				p = add1(ptrmask)
+			} else {
+				nb -= 8
+				p = ptrmask
+			}
+		}
+
+		// Emit bitmap byte.
+		hb = b & bitPointerAll
+		hb |= bitScanAll
+		if w += 4; w >= nw {
+			break
+		}
+		*hbitp = uint8(hb)
+		hbitp = add1(hbitp)
+		b >>= 4
+	}
+
+Phase3:
+	// Phase 3: Write last byte or partial byte and zero the rest of the bitmap entries.
+	if w > nw {
+		// Counting the 4 entries in hb not yet written to memory,
+		// there are more entries than possible pointer slots.
+		// Discard the excess entries (can't be more than 3).
+		mask := uintptr(1)<<(4-(w-nw)) - 1
+		hb &= mask | mask<<4 // apply mask to both pointer bits and scan bits
+	}
+
+	// Change nw from counting possibly-pointer words to total words in allocation.
+	nw = size / goarch.PtrSize
+
+	// Write whole bitmap bytes.
+	// The first is hb, the rest are zero.
+	if w <= nw {
+		*hbitp = uint8(hb)
+		hbitp = add1(hbitp)
+		hb = 0 // for possible final half-byte below
+		for w += 4; w <= nw; w += 4 {
+			*hbitp = 0
+			hbitp = add1(hbitp)
+		}
+	}
+
+	// Write final partial bitmap byte if any.
+	// We know w > nw, or else we'd still be in the loop above.
+	// It can be bigger only due to the 4 entries in hb that it counts.
+	// If w == nw+4 then there's nothing left to do: we wrote all nw entries
+	// and can discard the 4 sitting in hb.
+	// But if w == nw+2, we need to write first two in hb.
+	// The byte is shared with the next object, so be careful with
+	// existing bits.
+	if w == nw+2 {
+		*hbitp = *hbitp&^(bitPointer|bitScan|(bitPointer|bitScan)<<heapBitsShift) | uint8(hb)
+	}
+
+Phase4:
+	// Phase 4: Copy unrolled bitmap to per-arena bitmaps, if necessary.
+	if outOfPlace {
+		// TODO: We could probably make this faster by
+		// handling [x+dataSize, x+size) specially.
+		h := heapBitsForAddr(x)
+		// cnw is the number of heap words, or bit pairs
+		// remaining (like nw above).
+		cnw := size / goarch.PtrSize
+		src := (*uint8)(unsafe.Pointer(x))
+		// We know the first and last byte of the bitmap are
+		// not the same, but it's still possible for small
+		// objects span arenas, so it may share bitmap bytes
+		// with neighboring objects.
+		//
+		// Handle the first byte specially if it's shared. See
+		// Phase 1 for why this is the only special case we need.
+		if doubleCheck {
+			if !(h.shift == 0 || h.shift == 2) {
+				print("x=", x, " size=", size, " cnw=", h.shift, "\n")
+				throw("bad start shift")
+			}
+		}
+		if h.shift == 2 {
+			*h.bitp = *h.bitp&^((bitPointer|bitScan|(bitPointer|bitScan)<<heapBitsShift)<<(2*heapBitsShift)) | *src
+			h = h.next().next()
+			cnw -= 2
+			src = addb(src, 1)
+		}
+		// We're now byte aligned. Copy out to per-arena
+		// bitmaps until the last byte (which may again be
+		// partial).
+		for cnw >= 4 {
+			// This loop processes four words at a time,
+			// so round cnw down accordingly.
+			hNext, words := h.forwardOrBoundary(cnw / 4 * 4)
+
+			// n is the number of bitmap bytes to copy.
+			n := words / 4
+			memmove(unsafe.Pointer(h.bitp), unsafe.Pointer(src), n)
+			cnw -= words
+			h = hNext
+			src = addb(src, n)
+		}
+		if doubleCheck && h.shift != 0 {
+			print("cnw=", cnw, " h.shift=", h.shift, "\n")
+			throw("bad shift after block copy")
+		}
+		// Handle the last byte if it's shared.
+		if cnw == 2 {
+			*h.bitp = *h.bitp&^(bitPointer|bitScan|(bitPointer|bitScan)<<heapBitsShift) | *src
+			src = addb(src, 1)
+			h = h.next().next()
+		}
+		if doubleCheck {
+			if uintptr(unsafe.Pointer(src)) > x+size {
+				throw("copy exceeded object size")
+			}
+			if !(cnw == 0 || cnw == 2) {
+				print("x=", x, " size=", size, " cnw=", cnw, "\n")
+				throw("bad number of remaining words")
+			}
+			// Set up hbitp so doubleCheck code below can check it.
+			hbitp = h.bitp
+		}
+		// Zero the object where we wrote the bitmap.
+		memclrNoHeapPointers(unsafe.Pointer(x), uintptr(unsafe.Pointer(src))-x)
+	}
+
+	// Double check the whole bitmap.
+	if doubleCheck {
+		// x+size may not point to the heap, so back up one
+		// word and then advance it the way we do above.
+		end := heapBitsForAddr(x + size - goarch.PtrSize)
+		if outOfPlace {
+			// In out-of-place copying, we just advance
+			// using next.
+			end = end.next()
+		} else {
+			// Don't use next because that may advance to
+			// the next arena and the in-place logic
+			// doesn't do that.
+			end.shift += heapBitsShift
+			if end.shift == 4*heapBitsShift {
+				end.bitp, end.shift = add1(end.bitp), 0
+			}
+		}
+		if typ.kind&kindGCProg == 0 && (hbitp != end.bitp || (w == nw+2) != (end.shift == 2)) {
+			println("ended at wrong bitmap byte for", typ.string(), "x", dataSize/typ.size)
+			print("typ.size=", typ.size, " typ.ptrdata=", typ.ptrdata, " dataSize=", dataSize, " size=", size, "\n")
+			print("w=", w, " nw=", nw, " b=", hex(b), " nb=", nb, " hb=", hex(hb), "\n")
+			h0 := heapBitsForAddr(x)
+			print("initial bits h0.bitp=", h0.bitp, " h0.shift=", h0.shift, "\n")
+			print("ended at hbitp=", hbitp, " but next starts at bitp=", end.bitp, " shift=", end.shift, "\n")
+			throw("bad heapBitsSetType")
+		}
+
+		// Double-check that bits to be written were written correctly.
+		// Does not check that other bits were not written, unfortunately.
+		h := heapBitsForAddr(x)
+		nptr := typ.ptrdata / goarch.PtrSize
+		ndata := typ.size / goarch.PtrSize
+		count := dataSize / typ.size
+		totalptr := ((count-1)*typ.size + typ.ptrdata) / goarch.PtrSize
+		for i := uintptr(0); i < size/goarch.PtrSize; i++ {
+			j := i % ndata
+			var have, want uint8
+			have = (*h.bitp >> h.shift) & (bitPointer | bitScan)
+			if i >= totalptr {
+				if typ.kind&kindGCProg != 0 && i < (totalptr+3)/4*4 {
+					// heapBitsSetTypeGCProg always fills
+					// in full nibbles of bitScan.
+					want = bitScan
+				}
+			} else {
+				if j < nptr && (*addb(ptrmask, j/8)>>(j%8))&1 != 0 {
+					want |= bitPointer
+				}
+				want |= bitScan
+			}
+			if have != want {
+				println("mismatch writing bits for", typ.string(), "x", dataSize/typ.size)
+				print("typ.size=", typ.size, " typ.ptrdata=", typ.ptrdata, " dataSize=", dataSize, " size=", size, "\n")
+				print("kindGCProg=", typ.kind&kindGCProg != 0, " outOfPlace=", outOfPlace, "\n")
+				print("w=", w, " nw=", nw, " b=", hex(b), " nb=", nb, " hb=", hex(hb), "\n")
+				h0 := heapBitsForAddr(x)
+				print("initial bits h0.bitp=", h0.bitp, " h0.shift=", h0.shift, "\n")
+				print("current bits h.bitp=", h.bitp, " h.shift=", h.shift, " *h.bitp=", hex(*h.bitp), "\n")
+				print("ptrmask=", ptrmask, " p=", p, " endp=", endp, " endnb=", endnb, " pbits=", hex(pbits), " b=", hex(b), " nb=", nb, "\n")
+				println("at word", i, "offset", i*goarch.PtrSize, "have", hex(have), "want", hex(want))
+				if typ.kind&kindGCProg != 0 {
+					println("GC program:")
+					dumpGCProg(addb(typ.gcdata, 4))
+				}
+				throw("bad heapBitsSetType")
+			}
+			h = h.next()
+		}
+		if ptrmask == debugPtrmask.data {
+			unlock(&debugPtrmask.lock)
+		}
+	}
+}
+
+var debugPtrmask struct {
+	lock mutex
+	data *byte
+}
+
+// heapBitsSetTypeGCProg implements heapBitsSetType using a GC program.
+// progSize is the size of the memory described by the program.
+// elemSize is the size of the element that the GC program describes (a prefix of).
+// dataSize is the total size of the intended data, a multiple of elemSize.
+// allocSize is the total size of the allocated memory.
+//
+// GC programs are only used for large allocations.
+// heapBitsSetType requires that allocSize is a multiple of 4 words,
+// so that the relevant bitmap bytes are not shared with surrounding
+// objects.
+func heapBitsSetTypeGCProg(h heapBits, progSize, elemSize, dataSize, allocSize uintptr, prog *byte) {
+	if goarch.PtrSize == 8 && allocSize%(4*goarch.PtrSize) != 0 {
+		// Alignment will be wrong.
+		throw("heapBitsSetTypeGCProg: small allocation")
+	}
+	var totalBits uintptr
+	if elemSize == dataSize {
+		totalBits = runGCProg(prog, nil, h.bitp, 2)
+		if totalBits*goarch.PtrSize != progSize {
+			println("runtime: heapBitsSetTypeGCProg: total bits", totalBits, "but progSize", progSize)
+			throw("heapBitsSetTypeGCProg: unexpected bit count")
+		}
+	} else {
+		count := dataSize / elemSize
+
+		// Piece together program trailer to run after prog that does:
+		//	literal(0)
+		//	repeat(1, elemSize-progSize-1) // zeros to fill element size
+		//	repeat(elemSize, count-1) // repeat that element for count
+		// This zero-pads the data remaining in the first element and then
+		// repeats that first element to fill the array.
+		var trailer [40]byte // 3 varints (max 10 each) + some bytes
+		i := 0
+		if n := elemSize/goarch.PtrSize - progSize/goarch.PtrSize; n > 0 {
+			// literal(0)
+			trailer[i] = 0x01
+			i++
+			trailer[i] = 0
+			i++
+			if n > 1 {
+				// repeat(1, n-1)
+				trailer[i] = 0x81
+				i++
+				n--
+				for ; n >= 0x80; n >>= 7 {
+					trailer[i] = byte(n | 0x80)
+					i++
+				}
+				trailer[i] = byte(n)
+				i++
+			}
+		}
+		// repeat(elemSize/ptrSize, count-1)
+		trailer[i] = 0x80
+		i++
+		n := elemSize / goarch.PtrSize
+		for ; n >= 0x80; n >>= 7 {
+			trailer[i] = byte(n | 0x80)
+			i++
+		}
+		trailer[i] = byte(n)
+		i++
+		n = count - 1
+		for ; n >= 0x80; n >>= 7 {
+			trailer[i] = byte(n | 0x80)
+			i++
+		}
+		trailer[i] = byte(n)
+		i++
+		trailer[i] = 0
+		i++
+
+		runGCProg(prog, &trailer[0], h.bitp, 2)
+
+		// Even though we filled in the full array just now,
+		// record that we only filled in up to the ptrdata of the
+		// last element. This will cause the code below to
+		// memclr the dead section of the final array element,
+		// so that scanobject can stop early in the final element.
+		totalBits = (elemSize*(count-1) + progSize) / goarch.PtrSize
+	}
+	endProg := unsafe.Pointer(addb(h.bitp, (totalBits+3)/4))
+	endAlloc := unsafe.Pointer(addb(h.bitp, allocSize/goarch.PtrSize/wordsPerBitmapByte))
+	memclrNoHeapPointers(endProg, uintptr(endAlloc)-uintptr(endProg))
+}
+
+// progToPointerMask returns the 1-bit pointer mask output by the GC program prog.
+// size the size of the region described by prog, in bytes.
+// The resulting bitvector will have no more than size/goarch.PtrSize bits.
+func progToPointerMask(prog *byte, size uintptr) bitvector {
+	n := (size/goarch.PtrSize + 7) / 8
+	x := (*[1 << 30]byte)(persistentalloc(n+1, 1, &memstats.buckhash_sys))[:n+1]
+	x[len(x)-1] = 0xa1 // overflow check sentinel
+	n = runGCProg(prog, nil, &x[0], 1)
+	if x[len(x)-1] != 0xa1 {
+		throw("progToPointerMask: overflow")
+	}
+	return bitvector{int32(n), &x[0]}
+}
+
+// Packed GC pointer bitmaps, aka GC programs.
+//
+// For large types containing arrays, the type information has a
+// natural repetition that can be encoded to save space in the
+// binary and in the memory representation of the type information.
+//
+// The encoding is a simple Lempel-Ziv style bytecode machine
+// with the following instructions:
+//
+//	00000000: stop
+//	0nnnnnnn: emit n bits copied from the next (n+7)/8 bytes
+//	10000000 n c: repeat the previous n bits c times; n, c are varints
+//	1nnnnnnn c: repeat the previous n bits c times; c is a varint
+
+// runGCProg executes the GC program prog, and then trailer if non-nil,
+// writing to dst with entries of the given size.
+// If size == 1, dst is a 1-bit pointer mask laid out moving forward from dst.
+// If size == 2, dst is the 2-bit heap bitmap, and writes move backward
+// starting at dst (because the heap bitmap does). In this case, the caller guarantees
+// that only whole bytes in dst need to be written.
+//
+// runGCProg returns the number of 1- or 2-bit entries written to memory.
+func runGCProg(prog, trailer, dst *byte, size int) uintptr {
+	dstStart := dst
+
+	// Bits waiting to be written to memory.
+	var bits uintptr
+	var nbits uintptr
+
+	p := prog
+Run:
+	for {
+		// Flush accumulated full bytes.
+		// The rest of the loop assumes that nbits <= 7.
+		for ; nbits >= 8; nbits -= 8 {
+			if size == 1 {
+				*dst = uint8(bits)
+				dst = add1(dst)
+				bits >>= 8
+			} else {
+				v := bits&bitPointerAll | bitScanAll
+				*dst = uint8(v)
+				dst = add1(dst)
+				bits >>= 4
+				v = bits&bitPointerAll | bitScanAll
+				*dst = uint8(v)
+				dst = add1(dst)
+				bits >>= 4
+			}
+		}
+
+		// Process one instruction.
+		inst := uintptr(*p)
+		p = add1(p)
+		n := inst & 0x7F
+		if inst&0x80 == 0 {
+			// Literal bits; n == 0 means end of program.
+			if n == 0 {
+				// Program is over; continue in trailer if present.
+				if trailer != nil {
+					p = trailer
+					trailer = nil
+					continue
+				}
+				break Run
+			}
+			nbyte := n / 8
+			for i := uintptr(0); i < nbyte; i++ {
+				bits |= uintptr(*p) << nbits
+				p = add1(p)
+				if size == 1 {
+					*dst = uint8(bits)
+					dst = add1(dst)
+					bits >>= 8
+				} else {
+					v := bits&0xf | bitScanAll
+					*dst = uint8(v)
+					dst = add1(dst)
+					bits >>= 4
+					v = bits&0xf | bitScanAll
+					*dst = uint8(v)
+					dst = add1(dst)
+					bits >>= 4
+				}
+			}
+			if n %= 8; n > 0 {
+				bits |= uintptr(*p) << nbits
+				p = add1(p)
+				nbits += n
+			}
+			continue Run
+		}
+
+		// Repeat. If n == 0, it is encoded in a varint in the next bytes.
+		if n == 0 {
+			for off := uint(0); ; off += 7 {
+				x := uintptr(*p)
+				p = add1(p)
+				n |= (x & 0x7F) << off
+				if x&0x80 == 0 {
+					break
+				}
+			}
+		}
+
+		// Count is encoded in a varint in the next bytes.
+		c := uintptr(0)
+		for off := uint(0); ; off += 7 {
+			x := uintptr(*p)
+			p = add1(p)
+			c |= (x & 0x7F) << off
+			if x&0x80 == 0 {
+				break
+			}
+		}
+		c *= n // now total number of bits to copy
+
+		// If the number of bits being repeated is small, load them
+		// into a register and use that register for the entire loop
+		// instead of repeatedly reading from memory.
+		// Handling fewer than 8 bits here makes the general loop simpler.
+		// The cutoff is goarch.PtrSize*8 - 7 to guarantee that when we add
+		// the pattern to a bit buffer holding at most 7 bits (a partial byte)
+		// it will not overflow.
+		src := dst
+		const maxBits = goarch.PtrSize*8 - 7
+		if n <= maxBits {
+			// Start with bits in output buffer.
+			pattern := bits
+			npattern := nbits
+
+			// If we need more bits, fetch them from memory.
+			if size == 1 {
+				src = subtract1(src)
+				for npattern < n {
+					pattern <<= 8
+					pattern |= uintptr(*src)
+					src = subtract1(src)
+					npattern += 8
+				}
+			} else {
+				src = subtract1(src)
+				for npattern < n {
+					pattern <<= 4
+					pattern |= uintptr(*src) & 0xf
+					src = subtract1(src)
+					npattern += 4
+				}
+			}
+
+			// We started with the whole bit output buffer,
+			// and then we loaded bits from whole bytes.
+			// Either way, we might now have too many instead of too few.
+			// Discard the extra.
+			if npattern > n {
+				pattern >>= npattern - n
+				npattern = n
+			}
+
+			// Replicate pattern to at most maxBits.
+			if npattern == 1 {
+				// One bit being repeated.
+				// If the bit is 1, make the pattern all 1s.
+				// If the bit is 0, the pattern is already all 0s,
+				// but we can claim that the number of bits
+				// in the word is equal to the number we need (c),
+				// because right shift of bits will zero fill.
+				if pattern == 1 {
+					pattern = 1<<maxBits - 1
+					npattern = maxBits
+				} else {
+					npattern = c
+				}
+			} else {
+				b := pattern
+				nb := npattern
+				if nb+nb <= maxBits {
+					// Double pattern until the whole uintptr is filled.
+					for nb <= goarch.PtrSize*8 {
+						b |= b << nb
+						nb += nb
+					}
+					// Trim away incomplete copy of original pattern in high bits.
+					// TODO(rsc): Replace with table lookup or loop on systems without divide?
+					nb = maxBits / npattern * npattern
+					b &= 1<<nb - 1
+					pattern = b
+					npattern = nb
+				}
+			}
+
+			// Add pattern to bit buffer and flush bit buffer, c/npattern times.
+			// Since pattern contains >8 bits, there will be full bytes to flush
+			// on each iteration.
+			for ; c >= npattern; c -= npattern {
+				bits |= pattern << nbits
+				nbits += npattern
+				if size == 1 {
+					for nbits >= 8 {
+						*dst = uint8(bits)
+						dst = add1(dst)
+						bits >>= 8
+						nbits -= 8
+					}
+				} else {
+					for nbits >= 4 {
+						*dst = uint8(bits&0xf | bitScanAll)
+						dst = add1(dst)
+						bits >>= 4
+						nbits -= 4
+					}
+				}
+			}
+
+			// Add final fragment to bit buffer.
+			if c > 0 {
+				pattern &= 1<<c - 1
+				bits |= pattern << nbits
+				nbits += c
+			}
+			continue Run
+		}
+
+		// Repeat; n too large to fit in a register.
+		// Since nbits <= 7, we know the first few bytes of repeated data
+		// are already written to memory.
+		off := n - nbits // n > nbits because n > maxBits and nbits <= 7
+		if size == 1 {
+			// Leading src fragment.
+			src = subtractb(src, (off+7)/8)
+			if frag := off & 7; frag != 0 {
+				bits |= uintptr(*src) >> (8 - frag) << nbits
+				src = add1(src)
+				nbits += frag
+				c -= frag
+			}
+			// Main loop: load one byte, write another.
+			// The bits are rotating through the bit buffer.
+			for i := c / 8; i > 0; i-- {
+				bits |= uintptr(*src) << nbits
+				src = add1(src)
+				*dst = uint8(bits)
+				dst = add1(dst)
+				bits >>= 8
+			}
+			// Final src fragment.
+			if c %= 8; c > 0 {
+				bits |= (uintptr(*src) & (1<<c - 1)) << nbits
+				nbits += c
+			}
+		} else {
+			// Leading src fragment.
+			src = subtractb(src, (off+3)/4)
+			if frag := off & 3; frag != 0 {
+				bits |= (uintptr(*src) & 0xf) >> (4 - frag) << nbits
+				src = add1(src)
+				nbits += frag
+				c -= frag
+			}
+			// Main loop: load one byte, write another.
+			// The bits are rotating through the bit buffer.
+			for i := c / 4; i > 0; i-- {
+				bits |= (uintptr(*src) & 0xf) << nbits
+				src = add1(src)
+				*dst = uint8(bits&0xf | bitScanAll)
+				dst = add1(dst)
+				bits >>= 4
+			}
+			// Final src fragment.
+			if c %= 4; c > 0 {
+				bits |= (uintptr(*src) & (1<<c - 1)) << nbits
+				nbits += c
+			}
+		}
+	}
+
+	// Write any final bits out, using full-byte writes, even for the final byte.
+	var totalBits uintptr
+	if size == 1 {
+		totalBits = (uintptr(unsafe.Pointer(dst))-uintptr(unsafe.Pointer(dstStart)))*8 + nbits
+		nbits += -nbits & 7
+		for ; nbits > 0; nbits -= 8 {
+			*dst = uint8(bits)
+			dst = add1(dst)
+			bits >>= 8
+		}
+	} else {
+		totalBits = (uintptr(unsafe.Pointer(dst))-uintptr(unsafe.Pointer(dstStart)))*4 + nbits
+		nbits += -nbits & 3
+		for ; nbits > 0; nbits -= 4 {
+			v := bits&0xf | bitScanAll
+			*dst = uint8(v)
+			dst = add1(dst)
+			bits >>= 4
+		}
+	}
+	return totalBits
+}
+
+// materializeGCProg allocates space for the (1-bit) pointer bitmask
+// for an object of size ptrdata.  Then it fills that space with the
+// pointer bitmask specified by the program prog.
+// The bitmask starts at s.startAddr.
+// The result must be deallocated with dematerializeGCProg.
+func materializeGCProg(ptrdata uintptr, prog *byte) *mspan {
+	// Each word of ptrdata needs one bit in the bitmap.
+	bitmapBytes := divRoundUp(ptrdata, 8*goarch.PtrSize)
+	// Compute the number of pages needed for bitmapBytes.
+	pages := divRoundUp(bitmapBytes, pageSize)
+	s := mheap_.allocManual(pages, spanAllocPtrScalarBits)
+	runGCProg(addb(prog, 4), nil, (*byte)(unsafe.Pointer(s.startAddr)), 1)
+	return s
+}
+func dematerializeGCProg(s *mspan) {
+	mheap_.freeManual(s, spanAllocPtrScalarBits)
+}
+
+func dumpGCProg(p *byte) {
+	nptr := 0
+	for {
+		x := *p
+		p = add1(p)
+		if x == 0 {
+			print("\t", nptr, " end\n")
+			break
+		}
+		if x&0x80 == 0 {
+			print("\t", nptr, " lit ", x, ":")
+			n := int(x+7) / 8
+			for i := 0; i < n; i++ {
+				print(" ", hex(*p))
+				p = add1(p)
+			}
+			print("\n")
+			nptr += int(x)
+		} else {
+			nbit := int(x &^ 0x80)
+			if nbit == 0 {
+				for nb := uint(0); ; nb += 7 {
+					x := *p
+					p = add1(p)
+					nbit |= int(x&0x7f) << nb
+					if x&0x80 == 0 {
+						break
+					}
+				}
+			}
+			count := 0
+			for nb := uint(0); ; nb += 7 {
+				x := *p
+				p = add1(p)
+				count |= int(x&0x7f) << nb
+				if x&0x80 == 0 {
+					break
+				}
+			}
+			print("\t", nptr, " repeat ", nbit, " × ", count, "\n")
+			nptr += nbit * count
+		}
+	}
+}
+
+// Testing.
+
+func getgcmaskcb(frame *stkframe, ctxt unsafe.Pointer) bool {
+	target := (*stkframe)(ctxt)
+	if frame.sp <= target.sp && target.sp < frame.varp {
+		*target = *frame
+		return false
+	}
+	return true
+}
+
+// gcbits returns the GC type info for x, for testing.
+// The result is the bitmap entries (0 or 1), one entry per byte.
+//
+//go:linkname reflect_gcbits reflect.gcbits
+func reflect_gcbits(x any) []byte {
+	ret := getgcmask(x)
+	typ := (*ptrtype)(unsafe.Pointer(efaceOf(&x)._type)).elem
+	nptr := typ.ptrdata / goarch.PtrSize
+	for uintptr(len(ret)) > nptr && ret[len(ret)-1] == 0 {
+		ret = ret[:len(ret)-1]
+	}
+	return ret
+}
+
+// Returns GC type info for the pointer stored in ep for testing.
+// If ep points to the stack, only static live information will be returned
+// (i.e. not for objects which are only dynamically live stack objects).
+func getgcmask(ep any) (mask []byte) {
+	e := *efaceOf(&ep)
+	p := e.data
+	t := e._type
+	// data or bss
+	for _, datap := range activeModules() {
+		// data
+		if datap.data <= uintptr(p) && uintptr(p) < datap.edata {
+			bitmap := datap.gcdatamask.bytedata
+			n := (*ptrtype)(unsafe.Pointer(t)).elem.size
+			mask = make([]byte, n/goarch.PtrSize)
+			for i := uintptr(0); i < n; i += goarch.PtrSize {
+				off := (uintptr(p) + i - datap.data) / goarch.PtrSize
+				mask[i/goarch.PtrSize] = (*addb(bitmap, off/8) >> (off % 8)) & 1
+			}
+			return
+		}
+
+		// bss
+		if datap.bss <= uintptr(p) && uintptr(p) < datap.ebss {
+			bitmap := datap.gcbssmask.bytedata
+			n := (*ptrtype)(unsafe.Pointer(t)).elem.size
+			mask = make([]byte, n/goarch.PtrSize)
+			for i := uintptr(0); i < n; i += goarch.PtrSize {
+				off := (uintptr(p) + i - datap.bss) / goarch.PtrSize
+				mask[i/goarch.PtrSize] = (*addb(bitmap, off/8) >> (off % 8)) & 1
+			}
+			return
+		}
+	}
+
+	// heap
+	if base, s, _ := findObject(uintptr(p), 0, 0); base != 0 {
+		hbits := heapBitsForAddr(base)
+		n := s.elemsize
+		mask = make([]byte, n/goarch.PtrSize)
+		for i := uintptr(0); i < n; i += goarch.PtrSize {
+			if hbits.isPointer() {
+				mask[i/goarch.PtrSize] = 1
+			}
+			if !hbits.morePointers() {
+				mask = mask[:i/goarch.PtrSize]
+				break
+			}
+			hbits = hbits.next()
+		}
+		return
+	}
+
+	// stack
+	if _g_ := getg(); _g_.m.curg.stack.lo <= uintptr(p) && uintptr(p) < _g_.m.curg.stack.hi {
+		var frame stkframe
+		frame.sp = uintptr(p)
+		_g_ := getg()
+		gentraceback(_g_.m.curg.sched.pc, _g_.m.curg.sched.sp, 0, _g_.m.curg, 0, nil, 1000, getgcmaskcb, noescape(unsafe.Pointer(&frame)), 0)
+		if frame.fn.valid() {
+			locals, _, _ := getStackMap(&frame, nil, false)
+			if locals.n == 0 {
+				return
+			}
+			size := uintptr(locals.n) * goarch.PtrSize
+			n := (*ptrtype)(unsafe.Pointer(t)).elem.size
+			mask = make([]byte, n/goarch.PtrSize)
+			for i := uintptr(0); i < n; i += goarch.PtrSize {
+				off := (uintptr(p) + i - frame.varp + size) / goarch.PtrSize
+				mask[i/goarch.PtrSize] = locals.ptrbit(off)
+			}
+		}
+		return
+	}
+
+	// otherwise, not something the GC knows about.
+	// possibly read-only data, like malloc(0).
+	// must not have pointers
+	return
+}
diff --git a/contrib/go/_std_1.19/src/runtime/mcache.go b/contrib/go/_std_1.19/src/runtime/mcache.go
new file mode 100644
index 0000000000..1f484fb9b6
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/mcache.go
@@ -0,0 +1,329 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+// Per-thread (in Go, per-P) cache for small objects.
+// This includes a small object cache and local allocation stats.
+// No locking needed because it is per-thread (per-P).
+//
+// mcaches are allocated from non-GC'd memory, so any heap pointers
+// must be specially handled.
+//
+//go:notinheap
+type mcache struct {
+	// The following members are accessed on every malloc,
+	// so they are grouped here for better caching.
+	nextSample uintptr // trigger heap sample after allocating this many bytes
+	scanAlloc  uintptr // bytes of scannable heap allocated
+
+	// Allocator cache for tiny objects w/o pointers.
+	// See "Tiny allocator" comment in malloc.go.
+
+	// tiny points to the beginning of the current tiny block, or
+	// nil if there is no current tiny block.
+	//
+	// tiny is a heap pointer. Since mcache is in non-GC'd memory,
+	// we handle it by clearing it in releaseAll during mark
+	// termination.
+	//
+	// tinyAllocs is the number of tiny allocations performed
+	// by the P that owns this mcache.
+	tiny       uintptr
+	tinyoffset uintptr
+	tinyAllocs uintptr
+
+	// The rest is not accessed on every malloc.
+
+	alloc [numSpanClasses]*mspan // spans to allocate from, indexed by spanClass
+
+	stackcache [_NumStackOrders]stackfreelist
+
+	// flushGen indicates the sweepgen during which this mcache
+	// was last flushed. If flushGen != mheap_.sweepgen, the spans
+	// in this mcache are stale and need to the flushed so they
+	// can be swept. This is done in acquirep.
+	flushGen uint32
+}
+
+// A gclink is a node in a linked list of blocks, like mlink,
+// but it is opaque to the garbage collector.
+// The GC does not trace the pointers during collection,
+// and the compiler does not emit write barriers for assignments
+// of gclinkptr values. Code should store references to gclinks
+// as gclinkptr, not as *gclink.
+type gclink struct {
+	next gclinkptr
+}
+
+// A gclinkptr is a pointer to a gclink, but it is opaque
+// to the garbage collector.
+type gclinkptr uintptr
+
+// ptr returns the *gclink form of p.
+// The result should be used for accessing fields, not stored
+// in other data structures.
+func (p gclinkptr) ptr() *gclink {
+	return (*gclink)(unsafe.Pointer(p))
+}
+
+type stackfreelist struct {
+	list gclinkptr // linked list of free stacks
+	size uintptr   // total size of stacks in list
+}
+
+// dummy mspan that contains no free objects.
+var emptymspan mspan
+
+func allocmcache() *mcache {
+	var c *mcache
+	systemstack(func() {
+		lock(&mheap_.lock)
+		c = (*mcache)(mheap_.cachealloc.alloc())
+		c.flushGen = mheap_.sweepgen
+		unlock(&mheap_.lock)
+	})
+	for i := range c.alloc {
+		c.alloc[i] = &emptymspan
+	}
+	c.nextSample = nextSample()
+	return c
+}
+
+// freemcache releases resources associated with this
+// mcache and puts the object onto a free list.
+//
+// In some cases there is no way to simply release
+// resources, such as statistics, so donate them to
+// a different mcache (the recipient).
+func freemcache(c *mcache) {
+	systemstack(func() {
+		c.releaseAll()
+		stackcache_clear(c)
+
+		// NOTE(rsc,rlh): If gcworkbuffree comes back, we need to coordinate
+		// with the stealing of gcworkbufs during garbage collection to avoid
+		// a race where the workbuf is double-freed.
+		// gcworkbuffree(c.gcworkbuf)
+
+		lock(&mheap_.lock)
+		mheap_.cachealloc.free(unsafe.Pointer(c))
+		unlock(&mheap_.lock)
+	})
+}
+
+// getMCache is a convenience function which tries to obtain an mcache.
+//
+// Returns nil if we're not bootstrapping or we don't have a P. The caller's
+// P must not change, so we must be in a non-preemptible state.
+func getMCache(mp *m) *mcache {
+	// Grab the mcache, since that's where stats live.
+	pp := mp.p.ptr()
+	var c *mcache
+	if pp == nil {
+		// We will be called without a P while bootstrapping,
+		// in which case we use mcache0, which is set in mallocinit.
+		// mcache0 is cleared when bootstrapping is complete,
+		// by procresize.
+		c = mcache0
+	} else {
+		c = pp.mcache
+	}
+	return c
+}
+
+// refill acquires a new span of span class spc for c. This span will
+// have at least one free object. The current span in c must be full.
+//
+// Must run in a non-preemptible context since otherwise the owner of
+// c could change.
+func (c *mcache) refill(spc spanClass) {
+	// Return the current cached span to the central lists.
+	s := c.alloc[spc]
+
+	if uintptr(s.allocCount) != s.nelems {
+		throw("refill of span with free space remaining")
+	}
+	if s != &emptymspan {
+		// Mark this span as no longer cached.
+		if s.sweepgen != mheap_.sweepgen+3 {
+			throw("bad sweepgen in refill")
+		}
+		mheap_.central[spc].mcentral.uncacheSpan(s)
+
+		// Count up how many slots were used and record it.
+		stats := memstats.heapStats.acquire()
+		slotsUsed := int64(s.allocCount) - int64(s.allocCountBeforeCache)
+		atomic.Xadd64(&stats.smallAllocCount[spc.sizeclass()], slotsUsed)
+
+		// Flush tinyAllocs.
+		if spc == tinySpanClass {
+			atomic.Xadd64(&stats.tinyAllocCount, int64(c.tinyAllocs))
+			c.tinyAllocs = 0
+		}
+		memstats.heapStats.release()
+
+		// Count the allocs in inconsistent, internal stats.
+		bytesAllocated := slotsUsed * int64(s.elemsize)
+		gcController.totalAlloc.Add(bytesAllocated)
+
+		// Clear the second allocCount just to be safe.
+		s.allocCountBeforeCache = 0
+	}
+
+	// Get a new cached span from the central lists.
+	s = mheap_.central[spc].mcentral.cacheSpan()
+	if s == nil {
+		throw("out of memory")
+	}
+
+	if uintptr(s.allocCount) == s.nelems {
+		throw("span has no free space")
+	}
+
+	// Indicate that this span is cached and prevent asynchronous
+	// sweeping in the next sweep phase.
+	s.sweepgen = mheap_.sweepgen + 3
+
+	// Store the current alloc count for accounting later.
+	s.allocCountBeforeCache = s.allocCount
+
+	// Update heapLive and flush scanAlloc.
+	//
+	// We have not yet allocated anything new into the span, but we
+	// assume that all of its slots will get used, so this makes
+	// heapLive an overestimate.
+	//
+	// When the span gets uncached, we'll fix up this overestimate
+	// if necessary (see releaseAll).
+	//
+	// We pick an overestimate here because an underestimate leads
+	// the pacer to believe that it's in better shape than it is,
+	// which appears to lead to more memory used. See #53738 for
+	// more details.
+	usedBytes := uintptr(s.allocCount) * s.elemsize
+	gcController.update(int64(s.npages*pageSize)-int64(usedBytes), int64(c.scanAlloc))
+	c.scanAlloc = 0
+
+	c.alloc[spc] = s
+}
+
+// allocLarge allocates a span for a large object.
+func (c *mcache) allocLarge(size uintptr, noscan bool) *mspan {
+	if size+_PageSize < size {
+		throw("out of memory")
+	}
+	npages := size >> _PageShift
+	if size&_PageMask != 0 {
+		npages++
+	}
+
+	// Deduct credit for this span allocation and sweep if
+	// necessary. mHeap_Alloc will also sweep npages, so this only
+	// pays the debt down to npage pages.
+	deductSweepCredit(npages*_PageSize, npages)
+
+	spc := makeSpanClass(0, noscan)
+	s := mheap_.alloc(npages, spc)
+	if s == nil {
+		throw("out of memory")
+	}
+
+	// Count the alloc in consistent, external stats.
+	stats := memstats.heapStats.acquire()
+	atomic.Xadd64(&stats.largeAlloc, int64(npages*pageSize))
+	atomic.Xadd64(&stats.largeAllocCount, 1)
+	memstats.heapStats.release()
+
+	// Count the alloc in inconsistent, internal stats.
+	gcController.totalAlloc.Add(int64(npages * pageSize))
+
+	// Update heapLive.
+	gcController.update(int64(s.npages*pageSize), 0)
+
+	// Put the large span in the mcentral swept list so that it's
+	// visible to the background sweeper.
+	mheap_.central[spc].mcentral.fullSwept(mheap_.sweepgen).push(s)
+	s.limit = s.base() + size
+	heapBitsForAddr(s.base()).initSpan(s)
+	return s
+}
+
+func (c *mcache) releaseAll() {
+	// Take this opportunity to flush scanAlloc.
+	scanAlloc := int64(c.scanAlloc)
+	c.scanAlloc = 0
+
+	sg := mheap_.sweepgen
+	dHeapLive := int64(0)
+	for i := range c.alloc {
+		s := c.alloc[i]
+		if s != &emptymspan {
+			slotsUsed := int64(s.allocCount) - int64(s.allocCountBeforeCache)
+			s.allocCountBeforeCache = 0
+
+			// Adjust smallAllocCount for whatever was allocated.
+			stats := memstats.heapStats.acquire()
+			atomic.Xadd64(&stats.smallAllocCount[spanClass(i).sizeclass()], slotsUsed)
+			memstats.heapStats.release()
+
+			// Adjust the actual allocs in inconsistent, internal stats.
+			// We assumed earlier that the full span gets allocated.
+			gcController.totalAlloc.Add(slotsUsed * int64(s.elemsize))
+
+			if s.sweepgen != sg+1 {
+				// refill conservatively counted unallocated slots in gcController.heapLive.
+				// Undo this.
+				//
+				// If this span was cached before sweep, then gcController.heapLive was totally
+				// recomputed since caching this span, so we don't do this for stale spans.
+				dHeapLive -= int64(uintptr(s.nelems)-uintptr(s.allocCount)) * int64(s.elemsize)
+			}
+
+			// Release the span to the mcentral.
+			mheap_.central[i].mcentral.uncacheSpan(s)
+			c.alloc[i] = &emptymspan
+		}
+	}
+	// Clear tinyalloc pool.
+	c.tiny = 0
+	c.tinyoffset = 0
+
+	// Flush tinyAllocs.
+	stats := memstats.heapStats.acquire()
+	atomic.Xadd64(&stats.tinyAllocCount, int64(c.tinyAllocs))
+	c.tinyAllocs = 0
+	memstats.heapStats.release()
+
+	// Update heapLive and heapScan.
+	gcController.update(dHeapLive, scanAlloc)
+}
+
+// prepareForSweep flushes c if the system has entered a new sweep phase
+// since c was populated. This must happen between the sweep phase
+// starting and the first allocation from c.
+func (c *mcache) prepareForSweep() {
+	// Alternatively, instead of making sure we do this on every P
+	// between starting the world and allocating on that P, we
+	// could leave allocate-black on, allow allocation to continue
+	// as usual, use a ragged barrier at the beginning of sweep to
+	// ensure all cached spans are swept, and then disable
+	// allocate-black. However, with this approach it's difficult
+	// to avoid spilling mark bits into the *next* GC cycle.
+	sg := mheap_.sweepgen
+	if c.flushGen == sg {
+		return
+	} else if c.flushGen != sg-2 {
+		println("bad flushGen", c.flushGen, "in prepareForSweep; sweepgen", sg)
+		throw("bad flushGen")
+	}
+	c.releaseAll()
+	stackcache_clear(c)
+	atomic.Store(&c.flushGen, mheap_.sweepgen) // Synchronizes with gcStart
+}
diff --git a/contrib/go/_std_1.18/src/runtime/mcentral.go b/contrib/go/_std_1.19/src/runtime/mcentral.go
index e4bdf35071..e4bdf35071 100644
--- a/contrib/go/_std_1.18/src/runtime/mcentral.go
+++ b/contrib/go/_std_1.19/src/runtime/mcentral.go
diff --git a/contrib/go/_std_1.18/src/runtime/mcheckmark.go b/contrib/go/_std_1.19/src/runtime/mcheckmark.go
index 1dd28585f1..1dd28585f1 100644
--- a/contrib/go/_std_1.18/src/runtime/mcheckmark.go
+++ b/contrib/go/_std_1.19/src/runtime/mcheckmark.go
diff --git a/contrib/go/_std_1.19/src/runtime/mem.go b/contrib/go/_std_1.19/src/runtime/mem.go
new file mode 100644
index 0000000000..0ca933b25b
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/mem.go
@@ -0,0 +1,143 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import "unsafe"
+
+// OS memory management abstraction layer
+//
+// Regions of the address space managed by the runtime may be in one of four
+// states at any given time:
+// 1) None - Unreserved and unmapped, the default state of any region.
+// 2) Reserved - Owned by the runtime, but accessing it would cause a fault.
+//               Does not count against the process' memory footprint.
+// 3) Prepared - Reserved, intended not to be backed by physical memory (though
+//               an OS may implement this lazily). Can transition efficiently to
+//               Ready. Accessing memory in such a region is undefined (may
+//               fault, may give back unexpected zeroes, etc.).
+// 4) Ready - may be accessed safely.
+//
+// This set of states is more than is strictly necessary to support all the
+// currently supported platforms. One could get by with just None, Reserved, and
+// Ready. However, the Prepared state gives us flexibility for performance
+// purposes. For example, on POSIX-y operating systems, Reserved is usually a
+// private anonymous mmap'd region with PROT_NONE set, and to transition
+// to Ready would require setting PROT_READ|PROT_WRITE. However the
+// underspecification of Prepared lets us use just MADV_FREE to transition from
+// Ready to Prepared. Thus with the Prepared state we can set the permission
+// bits just once early on, we can efficiently tell the OS that it's free to
+// take pages away from us when we don't strictly need them.
+//
+// This file defines a cross-OS interface for a common set of helpers
+// that transition memory regions between these states. The helpers call into
+// OS-specific implementations that handle errors, while the interface boundary
+// implements cross-OS functionality, like updating runtime accounting.
+
+// sysAlloc transitions an OS-chosen region of memory from None to Ready.
+// More specifically, it obtains a large chunk of zeroed memory from the
+// operating system, typically on the order of a hundred kilobytes
+// or a megabyte. This memory is always immediately available for use.
+//
+// sysStat must be non-nil.
+//
+// Don't split the stack as this function may be invoked without a valid G,
+// which prevents us from allocating more stack.
+//
+//go:nosplit
+func sysAlloc(n uintptr, sysStat *sysMemStat) unsafe.Pointer {
+	sysStat.add(int64(n))
+	gcController.mappedReady.Add(int64(n))
+	return sysAllocOS(n)
+}
+
+// sysUnused transitions a memory region from Ready to Prepared. It notifies the
+// operating system that the physical pages backing this memory region are no
+// longer needed and can be reused for other purposes. The contents of a
+// sysUnused memory region are considered forfeit and the region must not be
+// accessed again until sysUsed is called.
+func sysUnused(v unsafe.Pointer, n uintptr) {
+	gcController.mappedReady.Add(-int64(n))
+	sysUnusedOS(v, n)
+}
+
+// sysUsed transitions a memory region from Prepared to Ready. It notifies the
+// operating system that the memory region is needed and ensures that the region
+// may be safely accessed. This is typically a no-op on systems that don't have
+// an explicit commit step and hard over-commit limits, but is critical on
+// Windows, for example.
+//
+// This operation is idempotent for memory already in the Prepared state, so
+// it is safe to refer, with v and n, to a range of memory that includes both
+// Prepared and Ready memory. However, the caller must provide the exact amount
+// of Prepared memory for accounting purposes.
+func sysUsed(v unsafe.Pointer, n, prepared uintptr) {
+	gcController.mappedReady.Add(int64(prepared))
+	sysUsedOS(v, n)
+}
+
+// sysHugePage does not transition memory regions, but instead provides a
+// hint to the OS that it would be more efficient to back this memory region
+// with pages of a larger size transparently.
+func sysHugePage(v unsafe.Pointer, n uintptr) {
+	sysHugePageOS(v, n)
+}
+
+// sysFree transitions a memory region from any state to None. Therefore, it
+// returns memory unconditionally. It is used if an out-of-memory error has been
+// detected midway through an allocation or to carve out an aligned section of
+// the address space. It is okay if sysFree is a no-op only if sysReserve always
+// returns a memory region aligned to the heap allocator's alignment
+// restrictions.
+//
+// sysStat must be non-nil.
+//
+// Don't split the stack as this function may be invoked without a valid G,
+// which prevents us from allocating more stack.
+//
+//go:nosplit
+func sysFree(v unsafe.Pointer, n uintptr, sysStat *sysMemStat) {
+	sysStat.add(-int64(n))
+	gcController.mappedReady.Add(-int64(n))
+	sysFreeOS(v, n)
+}
+
+// sysFault transitions a memory region from Ready to Reserved. It
+// marks a region such that it will always fault if accessed. Used only for
+// debugging the runtime.
+//
+// TODO(mknyszek): Currently it's true that all uses of sysFault transition
+// memory from Ready to Reserved, but this may not be true in the future
+// since on every platform the operation is much more general than that.
+// If a transition from Prepared is ever introduced, create a new function
+// that elides the Ready state accounting.
+func sysFault(v unsafe.Pointer, n uintptr) {
+	gcController.mappedReady.Add(-int64(n))
+	sysFaultOS(v, n)
+}
+
+// sysReserve transitions a memory region from None to Reserved. It reserves
+// address space in such a way that it would cause a fatal fault upon access
+// (either via permissions or not committing the memory). Such a reservation is
+// thus never backed by physical memory.
+//
+// If the pointer passed to it is non-nil, the caller wants the
+// reservation there, but sysReserve can still choose another
+// location if that one is unavailable.
+//
+// NOTE: sysReserve returns OS-aligned memory, but the heap allocator
+// may use larger alignment, so the caller must be careful to realign the
+// memory obtained by sysReserve.
+func sysReserve(v unsafe.Pointer, n uintptr) unsafe.Pointer {
+	return sysReserveOS(v, n)
+}
+
+// sysMap transitions a memory region from Reserved to Prepared. It ensures the
+// memory region can be efficiently transitioned to Ready.
+//
+// sysStat must be non-nil.
+func sysMap(v unsafe.Pointer, n uintptr, sysStat *sysMemStat) {
+	sysStat.add(int64(n))
+	sysMapOS(v, n)
+}
diff --git a/contrib/go/_std_1.19/src/runtime/mem_darwin.go b/contrib/go/_std_1.19/src/runtime/mem_darwin.go
new file mode 100644
index 0000000000..25862cf161
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/mem_darwin.go
@@ -0,0 +1,70 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"unsafe"
+)
+
+// Don't split the stack as this function may be invoked without a valid G,
+// which prevents us from allocating more stack.
+//
+//go:nosplit
+func sysAllocOS(n uintptr) unsafe.Pointer {
+	v, err := mmap(nil, n, _PROT_READ|_PROT_WRITE, _MAP_ANON|_MAP_PRIVATE, -1, 0)
+	if err != 0 {
+		return nil
+	}
+	return v
+}
+
+func sysUnusedOS(v unsafe.Pointer, n uintptr) {
+	// MADV_FREE_REUSABLE is like MADV_FREE except it also propagates
+	// accounting information about the process to task_info.
+	madvise(v, n, _MADV_FREE_REUSABLE)
+}
+
+func sysUsedOS(v unsafe.Pointer, n uintptr) {
+	// MADV_FREE_REUSE is necessary to keep the kernel's accounting
+	// accurate. If called on any memory region that hasn't been
+	// MADV_FREE_REUSABLE'd, it's a no-op.
+	madvise(v, n, _MADV_FREE_REUSE)
+}
+
+func sysHugePageOS(v unsafe.Pointer, n uintptr) {
+}
+
+// Don't split the stack as this function may be invoked without a valid G,
+// which prevents us from allocating more stack.
+//
+//go:nosplit
+func sysFreeOS(v unsafe.Pointer, n uintptr) {
+	munmap(v, n)
+}
+
+func sysFaultOS(v unsafe.Pointer, n uintptr) {
+	mmap(v, n, _PROT_NONE, _MAP_ANON|_MAP_PRIVATE|_MAP_FIXED, -1, 0)
+}
+
+func sysReserveOS(v unsafe.Pointer, n uintptr) unsafe.Pointer {
+	p, err := mmap(v, n, _PROT_NONE, _MAP_ANON|_MAP_PRIVATE, -1, 0)
+	if err != 0 {
+		return nil
+	}
+	return p
+}
+
+const _ENOMEM = 12
+
+func sysMapOS(v unsafe.Pointer, n uintptr) {
+	p, err := mmap(v, n, _PROT_READ|_PROT_WRITE, _MAP_ANON|_MAP_FIXED|_MAP_PRIVATE, -1, 0)
+	if err == _ENOMEM {
+		throw("runtime: out of memory")
+	}
+	if p != v || err != 0 {
+		print("runtime: mmap(", v, ", ", n, ") returned ", p, ", ", err, "\n")
+		throw("runtime: cannot map pages in arena address space")
+	}
+}
diff --git a/contrib/go/_std_1.19/src/runtime/mem_linux.go b/contrib/go/_std_1.19/src/runtime/mem_linux.go
new file mode 100644
index 0000000000..1630664cff
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/mem_linux.go
@@ -0,0 +1,193 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+const (
+	_EACCES = 13
+	_EINVAL = 22
+)
+
+// Don't split the stack as this method may be invoked without a valid G, which
+// prevents us from allocating more stack.
+//
+//go:nosplit
+func sysAllocOS(n uintptr) unsafe.Pointer {
+	p, err := mmap(nil, n, _PROT_READ|_PROT_WRITE, _MAP_ANON|_MAP_PRIVATE, -1, 0)
+	if err != 0 {
+		if err == _EACCES {
+			print("runtime: mmap: access denied\n")
+			exit(2)
+		}
+		if err == _EAGAIN {
+			print("runtime: mmap: too much locked memory (check 'ulimit -l').\n")
+			exit(2)
+		}
+		return nil
+	}
+	return p
+}
+
+var adviseUnused = uint32(_MADV_FREE)
+
+func sysUnusedOS(v unsafe.Pointer, n uintptr) {
+	// By default, Linux's "transparent huge page" support will
+	// merge pages into a huge page if there's even a single
+	// present regular page, undoing the effects of madvise(adviseUnused)
+	// below. On amd64, that means khugepaged can turn a single
+	// 4KB page to 2MB, bloating the process's RSS by as much as
+	// 512X. (See issue #8832 and Linux kernel bug
+	// https://bugzilla.kernel.org/show_bug.cgi?id=93111)
+	//
+	// To work around this, we explicitly disable transparent huge
+	// pages when we release pages of the heap. However, we have
+	// to do this carefully because changing this flag tends to
+	// split the VMA (memory mapping) containing v in to three
+	// VMAs in order to track the different values of the
+	// MADV_NOHUGEPAGE flag in the different regions. There's a
+	// default limit of 65530 VMAs per address space (sysctl
+	// vm.max_map_count), so we must be careful not to create too
+	// many VMAs (see issue #12233).
+	//
+	// Since huge pages are huge, there's little use in adjusting
+	// the MADV_NOHUGEPAGE flag on a fine granularity, so we avoid
+	// exploding the number of VMAs by only adjusting the
+	// MADV_NOHUGEPAGE flag on a large granularity. This still
+	// gets most of the benefit of huge pages while keeping the
+	// number of VMAs under control. With hugePageSize = 2MB, even
+	// a pessimal heap can reach 128GB before running out of VMAs.
+	if physHugePageSize != 0 {
+		// If it's a large allocation, we want to leave huge
+		// pages enabled. Hence, we only adjust the huge page
+		// flag on the huge pages containing v and v+n-1, and
+		// only if those aren't aligned.
+		var head, tail uintptr
+		if uintptr(v)&(physHugePageSize-1) != 0 {
+			// Compute huge page containing v.
+			head = alignDown(uintptr(v), physHugePageSize)
+		}
+		if (uintptr(v)+n)&(physHugePageSize-1) != 0 {
+			// Compute huge page containing v+n-1.
+			tail = alignDown(uintptr(v)+n-1, physHugePageSize)
+		}
+
+		// Note that madvise will return EINVAL if the flag is
+		// already set, which is quite likely. We ignore
+		// errors.
+		if head != 0 && head+physHugePageSize == tail {
+			// head and tail are different but adjacent,
+			// so do this in one call.
+			madvise(unsafe.Pointer(head), 2*physHugePageSize, _MADV_NOHUGEPAGE)
+		} else {
+			// Advise the huge pages containing v and v+n-1.
+			if head != 0 {
+				madvise(unsafe.Pointer(head), physHugePageSize, _MADV_NOHUGEPAGE)
+			}
+			if tail != 0 && tail != head {
+				madvise(unsafe.Pointer(tail), physHugePageSize, _MADV_NOHUGEPAGE)
+			}
+		}
+	}
+
+	if uintptr(v)&(physPageSize-1) != 0 || n&(physPageSize-1) != 0 {
+		// madvise will round this to any physical page
+		// *covered* by this range, so an unaligned madvise
+		// will release more memory than intended.
+		throw("unaligned sysUnused")
+	}
+
+	var advise uint32
+	if debug.madvdontneed != 0 {
+		advise = _MADV_DONTNEED
+	} else {
+		advise = atomic.Load(&adviseUnused)
+	}
+	if errno := madvise(v, n, int32(advise)); advise == _MADV_FREE && errno != 0 {
+		// MADV_FREE was added in Linux 4.5. Fall back to MADV_DONTNEED if it is
+		// not supported.
+		atomic.Store(&adviseUnused, _MADV_DONTNEED)
+		madvise(v, n, _MADV_DONTNEED)
+	}
+
+	if debug.harddecommit > 0 {
+		p, err := mmap(v, n, _PROT_NONE, _MAP_ANON|_MAP_FIXED|_MAP_PRIVATE, -1, 0)
+		if p != v || err != 0 {
+			throw("runtime: cannot disable permissions in address space")
+		}
+	}
+}
+
+func sysUsedOS(v unsafe.Pointer, n uintptr) {
+	if debug.harddecommit > 0 {
+		p, err := mmap(v, n, _PROT_READ|_PROT_WRITE, _MAP_ANON|_MAP_FIXED|_MAP_PRIVATE, -1, 0)
+		if err == _ENOMEM {
+			throw("runtime: out of memory")
+		}
+		if p != v || err != 0 {
+			throw("runtime: cannot remap pages in address space")
+		}
+		return
+
+		// Don't do the sysHugePage optimization in hard decommit mode.
+		// We're breaking up pages everywhere, there's no point.
+	}
+	// Partially undo the NOHUGEPAGE marks from sysUnused
+	// for whole huge pages between v and v+n. This may
+	// leave huge pages off at the end points v and v+n
+	// even though allocations may cover these entire huge
+	// pages. We could detect this and undo NOHUGEPAGE on
+	// the end points as well, but it's probably not worth
+	// the cost because when neighboring allocations are
+	// freed sysUnused will just set NOHUGEPAGE again.
+	sysHugePageOS(v, n)
+}
+
+func sysHugePageOS(v unsafe.Pointer, n uintptr) {
+	if physHugePageSize != 0 {
+		// Round v up to a huge page boundary.
+		beg := alignUp(uintptr(v), physHugePageSize)
+		// Round v+n down to a huge page boundary.
+		end := alignDown(uintptr(v)+n, physHugePageSize)
+
+		if beg < end {
+			madvise(unsafe.Pointer(beg), end-beg, _MADV_HUGEPAGE)
+		}
+	}
+}
+
+// Don't split the stack as this function may be invoked without a valid G,
+// which prevents us from allocating more stack.
+//
+//go:nosplit
+func sysFreeOS(v unsafe.Pointer, n uintptr) {
+	munmap(v, n)
+}
+
+func sysFaultOS(v unsafe.Pointer, n uintptr) {
+	mmap(v, n, _PROT_NONE, _MAP_ANON|_MAP_PRIVATE|_MAP_FIXED, -1, 0)
+}
+
+func sysReserveOS(v unsafe.Pointer, n uintptr) unsafe.Pointer {
+	p, err := mmap(v, n, _PROT_NONE, _MAP_ANON|_MAP_PRIVATE, -1, 0)
+	if err != 0 {
+		return nil
+	}
+	return p
+}
+
+func sysMapOS(v unsafe.Pointer, n uintptr) {
+	p, err := mmap(v, n, _PROT_READ|_PROT_WRITE, _MAP_ANON|_MAP_FIXED|_MAP_PRIVATE, -1, 0)
+	if err == _ENOMEM {
+		throw("runtime: out of memory")
+	}
+	if p != v || err != 0 {
+		print("runtime: mmap(", v, ", ", n, ") returned ", p, ", ", err, "\n")
+		throw("runtime: cannot map pages in arena address space")
+	}
+}
diff --git a/contrib/go/_std_1.19/src/runtime/memclr_amd64.s b/contrib/go/_std_1.19/src/runtime/memclr_amd64.s
new file mode 100644
index 0000000000..19bfa6f20d
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/memclr_amd64.s
@@ -0,0 +1,218 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !plan9
+
+#include "go_asm.h"
+#include "textflag.h"
+#include "asm_amd64.h"
+
+// See memclrNoHeapPointers Go doc for important implementation constraints.
+
+// func memclrNoHeapPointers(ptr unsafe.Pointer, n uintptr)
+// ABIInternal for performance.
+TEXT runtime·memclrNoHeapPointers<ABIInternal>(SB), NOSPLIT, $0-16
+	// AX = ptr
+	// BX = n
+	MOVQ	AX, DI	// DI = ptr
+	XORQ	AX, AX
+
+	// MOVOU seems always faster than REP STOSQ when Enhanced REP STOSQ is not available.
+tail:
+	// BSR+branch table make almost all memmove/memclr benchmarks worse. Not worth doing.
+	TESTQ	BX, BX
+	JEQ	_0
+	CMPQ	BX, $2
+	JBE	_1or2
+	CMPQ	BX, $4
+	JBE	_3or4
+	CMPQ	BX, $8
+	JB	_5through7
+	JE	_8
+	CMPQ	BX, $16
+	JBE	_9through16
+	CMPQ	BX, $32
+	JBE	_17through32
+	CMPQ	BX, $64
+	JBE	_33through64
+	CMPQ	BX, $128
+	JBE	_65through128
+	CMPQ	BX, $256
+	JBE	_129through256
+
+	CMPB	internal∕cpu·X86+const_offsetX86HasERMS(SB), $1 // enhanced REP MOVSB/STOSB
+	JNE	skip_erms
+
+	// If the size is less than 2kb, do not use ERMS as it has a big start-up cost.
+	// Table 3-4. Relative Performance of Memcpy() Using ERMSB Vs. 128-bit AVX
+	// in the Intel Optimization Guide shows better performance for ERMSB starting
+	// from 2KB. Benchmarks show the similar threshold for REP STOS vs AVX.
+	CMPQ    BX, $2048
+	JAE	loop_preheader_erms
+
+skip_erms:
+#ifndef hasAVX2
+	CMPB	internal∕cpu·X86+const_offsetX86HasAVX2(SB), $1
+	JE	loop_preheader_avx2
+	// TODO: for really big clears, use MOVNTDQ, even without AVX2.
+
+loop:
+	MOVOU	X15, 0(DI)
+	MOVOU	X15, 16(DI)
+	MOVOU	X15, 32(DI)
+	MOVOU	X15, 48(DI)
+	MOVOU	X15, 64(DI)
+	MOVOU	X15, 80(DI)
+	MOVOU	X15, 96(DI)
+	MOVOU	X15, 112(DI)
+	MOVOU	X15, 128(DI)
+	MOVOU	X15, 144(DI)
+	MOVOU	X15, 160(DI)
+	MOVOU	X15, 176(DI)
+	MOVOU	X15, 192(DI)
+	MOVOU	X15, 208(DI)
+	MOVOU	X15, 224(DI)
+	MOVOU	X15, 240(DI)
+	SUBQ	$256, BX
+	ADDQ	$256, DI
+	CMPQ	BX, $256
+	JAE	loop
+	JMP	tail
+#endif
+
+loop_preheader_avx2:
+	VPXOR X0, X0, X0
+	// For smaller sizes MOVNTDQ may be faster or slower depending on hardware.
+	// For larger sizes it is always faster, even on dual Xeons with 30M cache.
+	// TODO take into account actual LLC size. E. g. glibc uses LLC size/2.
+	CMPQ    BX, $0x2000000
+	JAE	loop_preheader_avx2_huge
+
+loop_avx2:
+	VMOVDQU	Y0, 0(DI)
+	VMOVDQU	Y0, 32(DI)
+	VMOVDQU	Y0, 64(DI)
+	VMOVDQU	Y0, 96(DI)
+	SUBQ	$128, BX
+	ADDQ	$128, DI
+	CMPQ	BX, $128
+	JAE	loop_avx2
+	VMOVDQU  Y0, -32(DI)(BX*1)
+	VMOVDQU  Y0, -64(DI)(BX*1)
+	VMOVDQU  Y0, -96(DI)(BX*1)
+	VMOVDQU  Y0, -128(DI)(BX*1)
+	VZEROUPPER
+	RET
+
+loop_preheader_erms:
+#ifndef hasAVX2
+	CMPB	internal∕cpu·X86+const_offsetX86HasAVX2(SB), $1
+	JNE	loop_erms
+#endif
+
+	VPXOR X0, X0, X0
+	// At this point both ERMS and AVX2 is supported. While REP STOS can use a no-RFO
+	// write protocol, ERMS could show the same or slower performance comparing to
+	// Non-Temporal Stores when the size is bigger than LLC depending on hardware.
+	CMPQ	BX, $0x2000000
+	JAE	loop_preheader_avx2_huge
+
+loop_erms:
+	// STOSQ is used to guarantee that the whole zeroed pointer-sized word is visible
+	// for a memory subsystem as the GC requires this.
+	MOVQ	BX, CX
+	SHRQ	$3, CX
+	ANDQ	$7, BX
+	REP;	STOSQ
+	JMP	tail
+
+loop_preheader_avx2_huge:
+	// Align to 32 byte boundary
+	VMOVDQU  Y0, 0(DI)
+	MOVQ	DI, SI
+	ADDQ	$32, DI
+	ANDQ	$~31, DI
+	SUBQ	DI, SI
+	ADDQ	SI, BX
+loop_avx2_huge:
+	VMOVNTDQ	Y0, 0(DI)
+	VMOVNTDQ	Y0, 32(DI)
+	VMOVNTDQ	Y0, 64(DI)
+	VMOVNTDQ	Y0, 96(DI)
+	SUBQ	$128, BX
+	ADDQ	$128, DI
+	CMPQ	BX, $128
+	JAE	loop_avx2_huge
+	// In the description of MOVNTDQ in [1]
+	// "... fencing operation implemented with the SFENCE or MFENCE instruction
+	// should be used in conjunction with MOVNTDQ instructions..."
+	// [1] 64-ia-32-architectures-software-developer-manual-325462.pdf
+	SFENCE
+	VMOVDQU  Y0, -32(DI)(BX*1)
+	VMOVDQU  Y0, -64(DI)(BX*1)
+	VMOVDQU  Y0, -96(DI)(BX*1)
+	VMOVDQU  Y0, -128(DI)(BX*1)
+	VZEROUPPER
+	RET
+
+_1or2:
+	MOVB	AX, (DI)
+	MOVB	AX, -1(DI)(BX*1)
+	RET
+_0:
+	RET
+_3or4:
+	MOVW	AX, (DI)
+	MOVW	AX, -2(DI)(BX*1)
+	RET
+_5through7:
+	MOVL	AX, (DI)
+	MOVL	AX, -4(DI)(BX*1)
+	RET
+_8:
+	// We need a separate case for 8 to make sure we clear pointers atomically.
+	MOVQ	AX, (DI)
+	RET
+_9through16:
+	MOVQ	AX, (DI)
+	MOVQ	AX, -8(DI)(BX*1)
+	RET
+_17through32:
+	MOVOU	X15, (DI)
+	MOVOU	X15, -16(DI)(BX*1)
+	RET
+_33through64:
+	MOVOU	X15, (DI)
+	MOVOU	X15, 16(DI)
+	MOVOU	X15, -32(DI)(BX*1)
+	MOVOU	X15, -16(DI)(BX*1)
+	RET
+_65through128:
+	MOVOU	X15, (DI)
+	MOVOU	X15, 16(DI)
+	MOVOU	X15, 32(DI)
+	MOVOU	X15, 48(DI)
+	MOVOU	X15, -64(DI)(BX*1)
+	MOVOU	X15, -48(DI)(BX*1)
+	MOVOU	X15, -32(DI)(BX*1)
+	MOVOU	X15, -16(DI)(BX*1)
+	RET
+_129through256:
+	MOVOU	X15, (DI)
+	MOVOU	X15, 16(DI)
+	MOVOU	X15, 32(DI)
+	MOVOU	X15, 48(DI)
+	MOVOU	X15, 64(DI)
+	MOVOU	X15, 80(DI)
+	MOVOU	X15, 96(DI)
+	MOVOU	X15, 112(DI)
+	MOVOU	X15, -128(DI)(BX*1)
+	MOVOU	X15, -112(DI)(BX*1)
+	MOVOU	X15, -96(DI)(BX*1)
+	MOVOU	X15, -80(DI)(BX*1)
+	MOVOU	X15, -64(DI)(BX*1)
+	MOVOU	X15, -48(DI)(BX*1)
+	MOVOU	X15, -32(DI)(BX*1)
+	MOVOU	X15, -16(DI)(BX*1)
+	RET
diff --git a/contrib/go/_std_1.19/src/runtime/memmove_amd64.s b/contrib/go/_std_1.19/src/runtime/memmove_amd64.s
new file mode 100644
index 0000000000..018bb0b19d
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/memmove_amd64.s
@@ -0,0 +1,532 @@
+// Derived from Inferno's libkern/memmove-386.s (adapted for amd64)
+// https://bitbucket.org/inferno-os/inferno-os/src/master/libkern/memmove-386.s
+//
+//         Copyright © 1994-1999 Lucent Technologies Inc. All rights reserved.
+//         Revisions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com).  All rights reserved.
+//         Portions Copyright 2009 The Go Authors. All rights reserved.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+//go:build !plan9
+
+#include "go_asm.h"
+#include "textflag.h"
+
+// See memmove Go doc for important implementation constraints.
+
+// func memmove(to, from unsafe.Pointer, n uintptr)
+// ABIInternal for performance.
+TEXT runtime·memmove<ABIInternal>(SB), NOSPLIT, $0-24
+	// AX = to
+	// BX = from
+	// CX = n
+	MOVQ	AX, DI
+	MOVQ	BX, SI
+	MOVQ	CX, BX
+
+	// REP instructions have a high startup cost, so we handle small sizes
+	// with some straightline code. The REP MOVSQ instruction is really fast
+	// for large sizes. The cutover is approximately 2K.
+tail:
+	// move_129through256 or smaller work whether or not the source and the
+	// destination memory regions overlap because they load all data into
+	// registers before writing it back.  move_256through2048 on the other
+	// hand can be used only when the memory regions don't overlap or the copy
+	// direction is forward.
+	//
+	// BSR+branch table make almost all memmove/memclr benchmarks worse. Not worth doing.
+	TESTQ	BX, BX
+	JEQ	move_0
+	CMPQ	BX, $2
+	JBE	move_1or2
+	CMPQ	BX, $4
+	JB	move_3
+	JBE	move_4
+	CMPQ	BX, $8
+	JB	move_5through7
+	JE	move_8
+	CMPQ	BX, $16
+	JBE	move_9through16
+	CMPQ	BX, $32
+	JBE	move_17through32
+	CMPQ	BX, $64
+	JBE	move_33through64
+	CMPQ	BX, $128
+	JBE	move_65through128
+	CMPQ	BX, $256
+	JBE	move_129through256
+
+	TESTB	$1, runtime·useAVXmemmove(SB)
+	JNZ	avxUnaligned
+
+/*
+ * check and set for backwards
+ */
+	CMPQ	SI, DI
+	JLS	back
+
+/*
+ * forward copy loop
+ */
+forward:
+	CMPQ	BX, $2048
+	JLS	move_256through2048
+
+	// If REP MOVSB isn't fast, don't use it
+	CMPB	internal∕cpu·X86+const_offsetX86HasERMS(SB), $1 // enhanced REP MOVSB/STOSB
+	JNE	fwdBy8
+
+	// Check alignment
+	MOVL	SI, AX
+	ORL	DI, AX
+	TESTL	$7, AX
+	JEQ	fwdBy8
+
+	// Do 1 byte at a time
+	MOVQ	BX, CX
+	REP;	MOVSB
+	RET
+
+fwdBy8:
+	// Do 8 bytes at a time
+	MOVQ	BX, CX
+	SHRQ	$3, CX
+	ANDQ	$7, BX
+	REP;	MOVSQ
+	JMP	tail
+
+back:
+/*
+ * check overlap
+ */
+	MOVQ	SI, CX
+	ADDQ	BX, CX
+	CMPQ	CX, DI
+	JLS	forward
+/*
+ * whole thing backwards has
+ * adjusted addresses
+ */
+	ADDQ	BX, DI
+	ADDQ	BX, SI
+	STD
+
+/*
+ * copy
+ */
+	MOVQ	BX, CX
+	SHRQ	$3, CX
+	ANDQ	$7, BX
+
+	SUBQ	$8, DI
+	SUBQ	$8, SI
+	REP;	MOVSQ
+
+	CLD
+	ADDQ	$8, DI
+	ADDQ	$8, SI
+	SUBQ	BX, DI
+	SUBQ	BX, SI
+	JMP	tail
+
+move_1or2:
+	MOVB	(SI), AX
+	MOVB	-1(SI)(BX*1), CX
+	MOVB	AX, (DI)
+	MOVB	CX, -1(DI)(BX*1)
+	RET
+move_0:
+	RET
+move_4:
+	MOVL	(SI), AX
+	MOVL	AX, (DI)
+	RET
+move_3:
+	MOVW	(SI), AX
+	MOVB	2(SI), CX
+	MOVW	AX, (DI)
+	MOVB	CX, 2(DI)
+	RET
+move_5through7:
+	MOVL	(SI), AX
+	MOVL	-4(SI)(BX*1), CX
+	MOVL	AX, (DI)
+	MOVL	CX, -4(DI)(BX*1)
+	RET
+move_8:
+	// We need a separate case for 8 to make sure we write pointers atomically.
+	MOVQ	(SI), AX
+	MOVQ	AX, (DI)
+	RET
+move_9through16:
+	MOVQ	(SI), AX
+	MOVQ	-8(SI)(BX*1), CX
+	MOVQ	AX, (DI)
+	MOVQ	CX, -8(DI)(BX*1)
+	RET
+move_17through32:
+	MOVOU	(SI), X0
+	MOVOU	-16(SI)(BX*1), X1
+	MOVOU	X0, (DI)
+	MOVOU	X1, -16(DI)(BX*1)
+	RET
+move_33through64:
+	MOVOU	(SI), X0
+	MOVOU	16(SI), X1
+	MOVOU	-32(SI)(BX*1), X2
+	MOVOU	-16(SI)(BX*1), X3
+	MOVOU	X0, (DI)
+	MOVOU	X1, 16(DI)
+	MOVOU	X2, -32(DI)(BX*1)
+	MOVOU	X3, -16(DI)(BX*1)
+	RET
+move_65through128:
+	MOVOU	(SI), X0
+	MOVOU	16(SI), X1
+	MOVOU	32(SI), X2
+	MOVOU	48(SI), X3
+	MOVOU	-64(SI)(BX*1), X4
+	MOVOU	-48(SI)(BX*1), X5
+	MOVOU	-32(SI)(BX*1), X6
+	MOVOU	-16(SI)(BX*1), X7
+	MOVOU	X0, (DI)
+	MOVOU	X1, 16(DI)
+	MOVOU	X2, 32(DI)
+	MOVOU	X3, 48(DI)
+	MOVOU	X4, -64(DI)(BX*1)
+	MOVOU	X5, -48(DI)(BX*1)
+	MOVOU	X6, -32(DI)(BX*1)
+	MOVOU	X7, -16(DI)(BX*1)
+	RET
+move_129through256:
+	MOVOU	(SI), X0
+	MOVOU	16(SI), X1
+	MOVOU	32(SI), X2
+	MOVOU	48(SI), X3
+	MOVOU	64(SI), X4
+	MOVOU	80(SI), X5
+	MOVOU	96(SI), X6
+	MOVOU	112(SI), X7
+	MOVOU	-128(SI)(BX*1), X8
+	MOVOU	-112(SI)(BX*1), X9
+	MOVOU	-96(SI)(BX*1), X10
+	MOVOU	-80(SI)(BX*1), X11
+	MOVOU	-64(SI)(BX*1), X12
+	MOVOU	-48(SI)(BX*1), X13
+	MOVOU	-32(SI)(BX*1), X14
+	MOVOU	-16(SI)(BX*1), X15
+	MOVOU	X0, (DI)
+	MOVOU	X1, 16(DI)
+	MOVOU	X2, 32(DI)
+	MOVOU	X3, 48(DI)
+	MOVOU	X4, 64(DI)
+	MOVOU	X5, 80(DI)
+	MOVOU	X6, 96(DI)
+	MOVOU	X7, 112(DI)
+	MOVOU	X8, -128(DI)(BX*1)
+	MOVOU	X9, -112(DI)(BX*1)
+	MOVOU	X10, -96(DI)(BX*1)
+	MOVOU	X11, -80(DI)(BX*1)
+	MOVOU	X12, -64(DI)(BX*1)
+	MOVOU	X13, -48(DI)(BX*1)
+	MOVOU	X14, -32(DI)(BX*1)
+	MOVOU	X15, -16(DI)(BX*1)
+	// X15 must be zero on return
+	PXOR	X15, X15
+	RET
+move_256through2048:
+	SUBQ	$256, BX
+	MOVOU	(SI), X0
+	MOVOU	16(SI), X1
+	MOVOU	32(SI), X2
+	MOVOU	48(SI), X3
+	MOVOU	64(SI), X4
+	MOVOU	80(SI), X5
+	MOVOU	96(SI), X6
+	MOVOU	112(SI), X7
+	MOVOU	128(SI), X8
+	MOVOU	144(SI), X9
+	MOVOU	160(SI), X10
+	MOVOU	176(SI), X11
+	MOVOU	192(SI), X12
+	MOVOU	208(SI), X13
+	MOVOU	224(SI), X14
+	MOVOU	240(SI), X15
+	MOVOU	X0, (DI)
+	MOVOU	X1, 16(DI)
+	MOVOU	X2, 32(DI)
+	MOVOU	X3, 48(DI)
+	MOVOU	X4, 64(DI)
+	MOVOU	X5, 80(DI)
+	MOVOU	X6, 96(DI)
+	MOVOU	X7, 112(DI)
+	MOVOU	X8, 128(DI)
+	MOVOU	X9, 144(DI)
+	MOVOU	X10, 160(DI)
+	MOVOU	X11, 176(DI)
+	MOVOU	X12, 192(DI)
+	MOVOU	X13, 208(DI)
+	MOVOU	X14, 224(DI)
+	MOVOU	X15, 240(DI)
+	CMPQ	BX, $256
+	LEAQ	256(SI), SI
+	LEAQ	256(DI), DI
+	JGE	move_256through2048
+	// X15 must be zero on return
+	PXOR	X15, X15
+	JMP	tail
+
+avxUnaligned:
+	// There are two implementations of move algorithm.
+	// The first one for non-overlapped memory regions. It uses forward copying.
+	// The second one for overlapped regions. It uses backward copying
+	MOVQ	DI, CX
+	SUBQ	SI, CX
+	// Now CX contains distance between SRC and DEST
+	CMPQ	CX, BX
+	// If the distance lesser than region length it means that regions are overlapped
+	JC	copy_backward
+
+	// Non-temporal copy would be better for big sizes.
+	CMPQ	BX, $0x100000
+	JAE	gobble_big_data_fwd
+
+	// Memory layout on the source side
+	// SI                                       CX
+	// |<---------BX before correction--------->|
+	// |       |<--BX corrected-->|             |
+	// |       |                  |<--- AX  --->|
+	// |<-R11->|                  |<-128 bytes->|
+	// +----------------------------------------+
+	// | Head  | Body             | Tail        |
+	// +-------+------------------+-------------+
+	// ^       ^                  ^
+	// |       |                  |
+	// Save head into Y4          Save tail into X5..X12
+	//         |
+	//         SI+R11, where R11 = ((DI & -32) + 32) - DI
+	// Algorithm:
+	// 1. Unaligned save of the tail's 128 bytes
+	// 2. Unaligned save of the head's 32  bytes
+	// 3. Destination-aligned copying of body (128 bytes per iteration)
+	// 4. Put head on the new place
+	// 5. Put the tail on the new place
+	// It can be important to satisfy processor's pipeline requirements for
+	// small sizes as the cost of unaligned memory region copying is
+	// comparable with the cost of main loop. So code is slightly messed there.
+	// There is more clean implementation of that algorithm for bigger sizes
+	// where the cost of unaligned part copying is negligible.
+	// You can see it after gobble_big_data_fwd label.
+	LEAQ	(SI)(BX*1), CX
+	MOVQ	DI, R10
+	// CX points to the end of buffer so we need go back slightly. We will use negative offsets there.
+	MOVOU	-0x80(CX), X5
+	MOVOU	-0x70(CX), X6
+	MOVQ	$0x80, AX
+	// Align destination address
+	ANDQ	$-32, DI
+	ADDQ	$32, DI
+	// Continue tail saving.
+	MOVOU	-0x60(CX), X7
+	MOVOU	-0x50(CX), X8
+	// Make R11 delta between aligned and unaligned destination addresses.
+	MOVQ	DI, R11
+	SUBQ	R10, R11
+	// Continue tail saving.
+	MOVOU	-0x40(CX), X9
+	MOVOU	-0x30(CX), X10
+	// Let's make bytes-to-copy value adjusted as we've prepared unaligned part for copying.
+	SUBQ	R11, BX
+	// Continue tail saving.
+	MOVOU	-0x20(CX), X11
+	MOVOU	-0x10(CX), X12
+	// The tail will be put on its place after main body copying.
+	// It's time for the unaligned heading part.
+	VMOVDQU	(SI), Y4
+	// Adjust source address to point past head.
+	ADDQ	R11, SI
+	SUBQ	AX, BX
+	// Aligned memory copying there
+gobble_128_loop:
+	VMOVDQU	(SI), Y0
+	VMOVDQU	0x20(SI), Y1
+	VMOVDQU	0x40(SI), Y2
+	VMOVDQU	0x60(SI), Y3
+	ADDQ	AX, SI
+	VMOVDQA	Y0, (DI)
+	VMOVDQA	Y1, 0x20(DI)
+	VMOVDQA	Y2, 0x40(DI)
+	VMOVDQA	Y3, 0x60(DI)
+	ADDQ	AX, DI
+	SUBQ	AX, BX
+	JA	gobble_128_loop
+	// Now we can store unaligned parts.
+	ADDQ	AX, BX
+	ADDQ	DI, BX
+	VMOVDQU	Y4, (R10)
+	VZEROUPPER
+	MOVOU	X5, -0x80(BX)
+	MOVOU	X6, -0x70(BX)
+	MOVOU	X7, -0x60(BX)
+	MOVOU	X8, -0x50(BX)
+	MOVOU	X9, -0x40(BX)
+	MOVOU	X10, -0x30(BX)
+	MOVOU	X11, -0x20(BX)
+	MOVOU	X12, -0x10(BX)
+	RET
+
+gobble_big_data_fwd:
+	// There is forward copying for big regions.
+	// It uses non-temporal mov instructions.
+	// Details of this algorithm are commented previously for small sizes.
+	LEAQ	(SI)(BX*1), CX
+	MOVOU	-0x80(SI)(BX*1), X5
+	MOVOU	-0x70(CX), X6
+	MOVOU	-0x60(CX), X7
+	MOVOU	-0x50(CX), X8
+	MOVOU	-0x40(CX), X9
+	MOVOU	-0x30(CX), X10
+	MOVOU	-0x20(CX), X11
+	MOVOU	-0x10(CX), X12
+	VMOVDQU	(SI), Y4
+	MOVQ	DI, R8
+	ANDQ	$-32, DI
+	ADDQ	$32, DI
+	MOVQ	DI, R10
+	SUBQ	R8, R10
+	SUBQ	R10, BX
+	ADDQ	R10, SI
+	LEAQ	(DI)(BX*1), CX
+	SUBQ	$0x80, BX
+gobble_mem_fwd_loop:
+	PREFETCHNTA 0x1C0(SI)
+	PREFETCHNTA 0x280(SI)
+	// Prefetch values were chosen empirically.
+	// Approach for prefetch usage as in 9.5.6 of [1]
+	// [1] 64-ia-32-architectures-optimization-manual.pdf
+	// https://www.intel.com/content/dam/www/public/us/en/documents/manuals/64-ia-32-architectures-optimization-manual.pdf
+	VMOVDQU	(SI), Y0
+	VMOVDQU	0x20(SI), Y1
+	VMOVDQU	0x40(SI), Y2
+	VMOVDQU	0x60(SI), Y3
+	ADDQ	$0x80, SI
+	VMOVNTDQ Y0, (DI)
+	VMOVNTDQ Y1, 0x20(DI)
+	VMOVNTDQ Y2, 0x40(DI)
+	VMOVNTDQ Y3, 0x60(DI)
+	ADDQ	$0x80, DI
+	SUBQ	$0x80, BX
+	JA		gobble_mem_fwd_loop
+	// NT instructions don't follow the normal cache-coherency rules.
+	// We need SFENCE there to make copied data available timely.
+	SFENCE
+	VMOVDQU	Y4, (R8)
+	VZEROUPPER
+	MOVOU	X5, -0x80(CX)
+	MOVOU	X6, -0x70(CX)
+	MOVOU	X7, -0x60(CX)
+	MOVOU	X8, -0x50(CX)
+	MOVOU	X9, -0x40(CX)
+	MOVOU	X10, -0x30(CX)
+	MOVOU	X11, -0x20(CX)
+	MOVOU	X12, -0x10(CX)
+	RET
+
+copy_backward:
+	MOVQ	DI, AX
+	// Backward copying is about the same as the forward one.
+	// Firstly we load unaligned tail in the beginning of region.
+	MOVOU	(SI), X5
+	MOVOU	0x10(SI), X6
+	ADDQ	BX, DI
+	MOVOU	0x20(SI), X7
+	MOVOU	0x30(SI), X8
+	LEAQ	-0x20(DI), R10
+	MOVQ	DI, R11
+	MOVOU	0x40(SI), X9
+	MOVOU	0x50(SI), X10
+	ANDQ	$0x1F, R11
+	MOVOU	0x60(SI), X11
+	MOVOU	0x70(SI), X12
+	XORQ	R11, DI
+	// Let's point SI to the end of region
+	ADDQ	BX, SI
+	// and load unaligned head into X4.
+	VMOVDQU	-0x20(SI), Y4
+	SUBQ	R11, SI
+	SUBQ	R11, BX
+	// If there is enough data for non-temporal moves go to special loop
+	CMPQ	BX, $0x100000
+	JA		gobble_big_data_bwd
+	SUBQ	$0x80, BX
+gobble_mem_bwd_loop:
+	VMOVDQU	-0x20(SI), Y0
+	VMOVDQU	-0x40(SI), Y1
+	VMOVDQU	-0x60(SI), Y2
+	VMOVDQU	-0x80(SI), Y3
+	SUBQ	$0x80, SI
+	VMOVDQA	Y0, -0x20(DI)
+	VMOVDQA	Y1, -0x40(DI)
+	VMOVDQA	Y2, -0x60(DI)
+	VMOVDQA	Y3, -0x80(DI)
+	SUBQ	$0x80, DI
+	SUBQ	$0x80, BX
+	JA		gobble_mem_bwd_loop
+	// Let's store unaligned data
+	VMOVDQU	Y4, (R10)
+	VZEROUPPER
+	MOVOU	X5, (AX)
+	MOVOU	X6, 0x10(AX)
+	MOVOU	X7, 0x20(AX)
+	MOVOU	X8, 0x30(AX)
+	MOVOU	X9, 0x40(AX)
+	MOVOU	X10, 0x50(AX)
+	MOVOU	X11, 0x60(AX)
+	MOVOU	X12, 0x70(AX)
+	RET
+
+gobble_big_data_bwd:
+	SUBQ	$0x80, BX
+gobble_big_mem_bwd_loop:
+	PREFETCHNTA -0x1C0(SI)
+	PREFETCHNTA -0x280(SI)
+	VMOVDQU	-0x20(SI), Y0
+	VMOVDQU	-0x40(SI), Y1
+	VMOVDQU	-0x60(SI), Y2
+	VMOVDQU	-0x80(SI), Y3
+	SUBQ	$0x80, SI
+	VMOVNTDQ	Y0, -0x20(DI)
+	VMOVNTDQ	Y1, -0x40(DI)
+	VMOVNTDQ	Y2, -0x60(DI)
+	VMOVNTDQ	Y3, -0x80(DI)
+	SUBQ	$0x80, DI
+	SUBQ	$0x80, BX
+	JA	gobble_big_mem_bwd_loop
+	SFENCE
+	VMOVDQU	Y4, (R10)
+	VZEROUPPER
+	MOVOU	X5, (AX)
+	MOVOU	X6, 0x10(AX)
+	MOVOU	X7, 0x20(AX)
+	MOVOU	X8, 0x30(AX)
+	MOVOU	X9, 0x40(AX)
+	MOVOU	X10, 0x50(AX)
+	MOVOU	X11, 0x60(AX)
+	MOVOU	X12, 0x70(AX)
+	RET
diff --git a/contrib/go/_std_1.19/src/runtime/metrics.go b/contrib/go/_std_1.19/src/runtime/metrics.go
new file mode 100644
index 0000000000..986121b9c2
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/metrics.go
@@ -0,0 +1,618 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+// Metrics implementation exported to runtime/metrics.
+
+import (
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+var (
+	// metrics is a map of runtime/metrics keys to data used by the runtime
+	// to sample each metric's value. metricsInit indicates it has been
+	// initialized.
+	//
+	// These fields are protected by metricsSema which should be
+	// locked/unlocked with metricsLock() / metricsUnlock().
+	metricsSema uint32 = 1
+	metricsInit bool
+	metrics     map[string]metricData
+
+	sizeClassBuckets []float64
+	timeHistBuckets  []float64
+)
+
+type metricData struct {
+	// deps is the set of runtime statistics that this metric
+	// depends on. Before compute is called, the statAggregate
+	// which will be passed must ensure() these dependencies.
+	deps statDepSet
+
+	// compute is a function that populates a metricValue
+	// given a populated statAggregate structure.
+	compute func(in *statAggregate, out *metricValue)
+}
+
+func metricsLock() {
+	// Acquire the metricsSema but with handoff. Operations are typically
+	// expensive enough that queueing up goroutines and handing off between
+	// them will be noticeably better-behaved.
+	semacquire1(&metricsSema, true, 0, 0)
+	if raceenabled {
+		raceacquire(unsafe.Pointer(&metricsSema))
+	}
+}
+
+func metricsUnlock() {
+	if raceenabled {
+		racerelease(unsafe.Pointer(&metricsSema))
+	}
+	semrelease(&metricsSema)
+}
+
+// initMetrics initializes the metrics map if it hasn't been yet.
+//
+// metricsSema must be held.
+func initMetrics() {
+	if metricsInit {
+		return
+	}
+
+	sizeClassBuckets = make([]float64, _NumSizeClasses, _NumSizeClasses+1)
+	// Skip size class 0 which is a stand-in for large objects, but large
+	// objects are tracked separately (and they actually get placed in
+	// the last bucket, not the first).
+	sizeClassBuckets[0] = 1 // The smallest allocation is 1 byte in size.
+	for i := 1; i < _NumSizeClasses; i++ {
+		// Size classes have an inclusive upper-bound
+		// and exclusive lower bound (e.g. 48-byte size class is
+		// (32, 48]) whereas we want and inclusive lower-bound
+		// and exclusive upper-bound (e.g. 48-byte size class is
+		// [33, 49). We can achieve this by shifting all bucket
+		// boundaries up by 1.
+		//
+		// Also, a float64 can precisely represent integers with
+		// value up to 2^53 and size classes are relatively small
+		// (nowhere near 2^48 even) so this will give us exact
+		// boundaries.
+		sizeClassBuckets[i] = float64(class_to_size[i] + 1)
+	}
+	sizeClassBuckets = append(sizeClassBuckets, float64Inf())
+
+	timeHistBuckets = timeHistogramMetricsBuckets()
+	metrics = map[string]metricData{
+		"/cgo/go-to-c-calls:calls": {
+			compute: func(_ *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = uint64(NumCgoCall())
+			},
+		},
+		"/gc/cycles/automatic:gc-cycles": {
+			deps: makeStatDepSet(sysStatsDep),
+			compute: func(in *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = in.sysStats.gcCyclesDone - in.sysStats.gcCyclesForced
+			},
+		},
+		"/gc/cycles/forced:gc-cycles": {
+			deps: makeStatDepSet(sysStatsDep),
+			compute: func(in *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = in.sysStats.gcCyclesForced
+			},
+		},
+		"/gc/cycles/total:gc-cycles": {
+			deps: makeStatDepSet(sysStatsDep),
+			compute: func(in *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = in.sysStats.gcCyclesDone
+			},
+		},
+		"/gc/heap/allocs-by-size:bytes": {
+			deps: makeStatDepSet(heapStatsDep),
+			compute: func(in *statAggregate, out *metricValue) {
+				hist := out.float64HistOrInit(sizeClassBuckets)
+				hist.counts[len(hist.counts)-1] = uint64(in.heapStats.largeAllocCount)
+				// Cut off the first index which is ostensibly for size class 0,
+				// but large objects are tracked separately so it's actually unused.
+				for i, count := range in.heapStats.smallAllocCount[1:] {
+					hist.counts[i] = uint64(count)
+				}
+			},
+		},
+		"/gc/heap/allocs:bytes": {
+			deps: makeStatDepSet(heapStatsDep),
+			compute: func(in *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = in.heapStats.totalAllocated
+			},
+		},
+		"/gc/heap/allocs:objects": {
+			deps: makeStatDepSet(heapStatsDep),
+			compute: func(in *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = in.heapStats.totalAllocs
+			},
+		},
+		"/gc/heap/frees-by-size:bytes": {
+			deps: makeStatDepSet(heapStatsDep),
+			compute: func(in *statAggregate, out *metricValue) {
+				hist := out.float64HistOrInit(sizeClassBuckets)
+				hist.counts[len(hist.counts)-1] = uint64(in.heapStats.largeFreeCount)
+				// Cut off the first index which is ostensibly for size class 0,
+				// but large objects are tracked separately so it's actually unused.
+				for i, count := range in.heapStats.smallFreeCount[1:] {
+					hist.counts[i] = uint64(count)
+				}
+			},
+		},
+		"/gc/heap/frees:bytes": {
+			deps: makeStatDepSet(heapStatsDep),
+			compute: func(in *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = in.heapStats.totalFreed
+			},
+		},
+		"/gc/heap/frees:objects": {
+			deps: makeStatDepSet(heapStatsDep),
+			compute: func(in *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = in.heapStats.totalFrees
+			},
+		},
+		"/gc/heap/goal:bytes": {
+			deps: makeStatDepSet(sysStatsDep),
+			compute: func(in *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = in.sysStats.heapGoal
+			},
+		},
+		"/gc/heap/objects:objects": {
+			deps: makeStatDepSet(heapStatsDep),
+			compute: func(in *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = in.heapStats.numObjects
+			},
+		},
+		"/gc/heap/tiny/allocs:objects": {
+			deps: makeStatDepSet(heapStatsDep),
+			compute: func(in *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = uint64(in.heapStats.tinyAllocCount)
+			},
+		},
+		"/gc/limiter/last-enabled:gc-cycle": {
+			compute: func(_ *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = uint64(gcCPULimiter.lastEnabledCycle.Load())
+			},
+		},
+		"/gc/pauses:seconds": {
+			compute: func(_ *statAggregate, out *metricValue) {
+				hist := out.float64HistOrInit(timeHistBuckets)
+				// The bottom-most bucket, containing negative values, is tracked
+				// as a separately as underflow, so fill that in manually and then
+				// iterate over the rest.
+				hist.counts[0] = atomic.Load64(&memstats.gcPauseDist.underflow)
+				for i := range memstats.gcPauseDist.counts {
+					hist.counts[i+1] = atomic.Load64(&memstats.gcPauseDist.counts[i])
+				}
+			},
+		},
+		"/gc/stack/starting-size:bytes": {
+			compute: func(in *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = uint64(startingStackSize)
+			},
+		},
+		"/memory/classes/heap/free:bytes": {
+			deps: makeStatDepSet(heapStatsDep),
+			compute: func(in *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = uint64(in.heapStats.committed - in.heapStats.inHeap -
+					in.heapStats.inStacks - in.heapStats.inWorkBufs -
+					in.heapStats.inPtrScalarBits)
+			},
+		},
+		"/memory/classes/heap/objects:bytes": {
+			deps: makeStatDepSet(heapStatsDep),
+			compute: func(in *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = in.heapStats.inObjects
+			},
+		},
+		"/memory/classes/heap/released:bytes": {
+			deps: makeStatDepSet(heapStatsDep),
+			compute: func(in *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = uint64(in.heapStats.released)
+			},
+		},
+		"/memory/classes/heap/stacks:bytes": {
+			deps: makeStatDepSet(heapStatsDep),
+			compute: func(in *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = uint64(in.heapStats.inStacks)
+			},
+		},
+		"/memory/classes/heap/unused:bytes": {
+			deps: makeStatDepSet(heapStatsDep),
+			compute: func(in *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = uint64(in.heapStats.inHeap) - in.heapStats.inObjects
+			},
+		},
+		"/memory/classes/metadata/mcache/free:bytes": {
+			deps: makeStatDepSet(sysStatsDep),
+			compute: func(in *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = in.sysStats.mCacheSys - in.sysStats.mCacheInUse
+			},
+		},
+		"/memory/classes/metadata/mcache/inuse:bytes": {
+			deps: makeStatDepSet(sysStatsDep),
+			compute: func(in *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = in.sysStats.mCacheInUse
+			},
+		},
+		"/memory/classes/metadata/mspan/free:bytes": {
+			deps: makeStatDepSet(sysStatsDep),
+			compute: func(in *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = in.sysStats.mSpanSys - in.sysStats.mSpanInUse
+			},
+		},
+		"/memory/classes/metadata/mspan/inuse:bytes": {
+			deps: makeStatDepSet(sysStatsDep),
+			compute: func(in *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = in.sysStats.mSpanInUse
+			},
+		},
+		"/memory/classes/metadata/other:bytes": {
+			deps: makeStatDepSet(heapStatsDep, sysStatsDep),
+			compute: func(in *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = uint64(in.heapStats.inWorkBufs+in.heapStats.inPtrScalarBits) + in.sysStats.gcMiscSys
+			},
+		},
+		"/memory/classes/os-stacks:bytes": {
+			deps: makeStatDepSet(sysStatsDep),
+			compute: func(in *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = in.sysStats.stacksSys
+			},
+		},
+		"/memory/classes/other:bytes": {
+			deps: makeStatDepSet(sysStatsDep),
+			compute: func(in *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = in.sysStats.otherSys
+			},
+		},
+		"/memory/classes/profiling/buckets:bytes": {
+			deps: makeStatDepSet(sysStatsDep),
+			compute: func(in *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = in.sysStats.buckHashSys
+			},
+		},
+		"/memory/classes/total:bytes": {
+			deps: makeStatDepSet(heapStatsDep, sysStatsDep),
+			compute: func(in *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = uint64(in.heapStats.committed+in.heapStats.released) +
+					in.sysStats.stacksSys + in.sysStats.mSpanSys +
+					in.sysStats.mCacheSys + in.sysStats.buckHashSys +
+					in.sysStats.gcMiscSys + in.sysStats.otherSys
+			},
+		},
+		"/sched/gomaxprocs:threads": {
+			compute: func(_ *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = uint64(gomaxprocs)
+			},
+		},
+		"/sched/goroutines:goroutines": {
+			compute: func(_ *statAggregate, out *metricValue) {
+				out.kind = metricKindUint64
+				out.scalar = uint64(gcount())
+			},
+		},
+		"/sched/latencies:seconds": {
+			compute: func(_ *statAggregate, out *metricValue) {
+				hist := out.float64HistOrInit(timeHistBuckets)
+				hist.counts[0] = atomic.Load64(&sched.timeToRun.underflow)
+				for i := range sched.timeToRun.counts {
+					hist.counts[i+1] = atomic.Load64(&sched.timeToRun.counts[i])
+				}
+			},
+		},
+	}
+	metricsInit = true
+}
+
+// statDep is a dependency on a group of statistics
+// that a metric might have.
+type statDep uint
+
+const (
+	heapStatsDep statDep = iota // corresponds to heapStatsAggregate
+	sysStatsDep                 // corresponds to sysStatsAggregate
+	numStatsDeps
+)
+
+// statDepSet represents a set of statDeps.
+//
+// Under the hood, it's a bitmap.
+type statDepSet [1]uint64
+
+// makeStatDepSet creates a new statDepSet from a list of statDeps.
+func makeStatDepSet(deps ...statDep) statDepSet {
+	var s statDepSet
+	for _, d := range deps {
+		s[d/64] |= 1 << (d % 64)
+	}
+	return s
+}
+
+// differennce returns set difference of s from b as a new set.
+func (s statDepSet) difference(b statDepSet) statDepSet {
+	var c statDepSet
+	for i := range s {
+		c[i] = s[i] &^ b[i]
+	}
+	return c
+}
+
+// union returns the union of the two sets as a new set.
+func (s statDepSet) union(b statDepSet) statDepSet {
+	var c statDepSet
+	for i := range s {
+		c[i] = s[i] | b[i]
+	}
+	return c
+}
+
+// empty returns true if there are no dependencies in the set.
+func (s *statDepSet) empty() bool {
+	for _, c := range s {
+		if c != 0 {
+			return false
+		}
+	}
+	return true
+}
+
+// has returns true if the set contains a given statDep.
+func (s *statDepSet) has(d statDep) bool {
+	return s[d/64]&(1<<(d%64)) != 0
+}
+
+// heapStatsAggregate represents memory stats obtained from the
+// runtime. This set of stats is grouped together because they
+// depend on each other in some way to make sense of the runtime's
+// current heap memory use. They're also sharded across Ps, so it
+// makes sense to grab them all at once.
+type heapStatsAggregate struct {
+	heapStatsDelta
+
+	// Derived from values in heapStatsDelta.
+
+	// inObjects is the bytes of memory occupied by objects,
+	inObjects uint64
+
+	// numObjects is the number of live objects in the heap.
+	numObjects uint64
+
+	// totalAllocated is the total bytes of heap objects allocated
+	// over the lifetime of the program.
+	totalAllocated uint64
+
+	// totalFreed is the total bytes of heap objects freed
+	// over the lifetime of the program.
+	totalFreed uint64
+
+	// totalAllocs is the number of heap objects allocated over
+	// the lifetime of the program.
+	totalAllocs uint64
+
+	// totalFrees is the number of heap objects freed over
+	// the lifetime of the program.
+	totalFrees uint64
+}
+
+// compute populates the heapStatsAggregate with values from the runtime.
+func (a *heapStatsAggregate) compute() {
+	memstats.heapStats.read(&a.heapStatsDelta)
+
+	// Calculate derived stats.
+	a.totalAllocs = a.largeAllocCount
+	a.totalFrees = a.largeFreeCount
+	a.totalAllocated = a.largeAlloc
+	a.totalFreed = a.largeFree
+	for i := range a.smallAllocCount {
+		na := a.smallAllocCount[i]
+		nf := a.smallFreeCount[i]
+		a.totalAllocs += na
+		a.totalFrees += nf
+		a.totalAllocated += na * uint64(class_to_size[i])
+		a.totalFreed += nf * uint64(class_to_size[i])
+	}
+	a.inObjects = a.totalAllocated - a.totalFreed
+	a.numObjects = a.totalAllocs - a.totalFrees
+}
+
+// sysStatsAggregate represents system memory stats obtained
+// from the runtime. This set of stats is grouped together because
+// they're all relatively cheap to acquire and generally independent
+// of one another and other runtime memory stats. The fact that they
+// may be acquired at different times, especially with respect to
+// heapStatsAggregate, means there could be some skew, but because of
+// these stats are independent, there's no real consistency issue here.
+type sysStatsAggregate struct {
+	stacksSys      uint64
+	mSpanSys       uint64
+	mSpanInUse     uint64
+	mCacheSys      uint64
+	mCacheInUse    uint64
+	buckHashSys    uint64
+	gcMiscSys      uint64
+	otherSys       uint64
+	heapGoal       uint64
+	gcCyclesDone   uint64
+	gcCyclesForced uint64
+}
+
+// compute populates the sysStatsAggregate with values from the runtime.
+func (a *sysStatsAggregate) compute() {
+	a.stacksSys = memstats.stacks_sys.load()
+	a.buckHashSys = memstats.buckhash_sys.load()
+	a.gcMiscSys = memstats.gcMiscSys.load()
+	a.otherSys = memstats.other_sys.load()
+	a.heapGoal = gcController.heapGoal()
+	a.gcCyclesDone = uint64(memstats.numgc)
+	a.gcCyclesForced = uint64(memstats.numforcedgc)
+
+	systemstack(func() {
+		lock(&mheap_.lock)
+		a.mSpanSys = memstats.mspan_sys.load()
+		a.mSpanInUse = uint64(mheap_.spanalloc.inuse)
+		a.mCacheSys = memstats.mcache_sys.load()
+		a.mCacheInUse = uint64(mheap_.cachealloc.inuse)
+		unlock(&mheap_.lock)
+	})
+}
+
+// statAggregate is the main driver of the metrics implementation.
+//
+// It contains multiple aggregates of runtime statistics, as well
+// as a set of these aggregates that it has populated. The aggergates
+// are populated lazily by its ensure method.
+type statAggregate struct {
+	ensured   statDepSet
+	heapStats heapStatsAggregate
+	sysStats  sysStatsAggregate
+}
+
+// ensure populates statistics aggregates determined by deps if they
+// haven't yet been populated.
+func (a *statAggregate) ensure(deps *statDepSet) {
+	missing := deps.difference(a.ensured)
+	if missing.empty() {
+		return
+	}
+	for i := statDep(0); i < numStatsDeps; i++ {
+		if !missing.has(i) {
+			continue
+		}
+		switch i {
+		case heapStatsDep:
+			a.heapStats.compute()
+		case sysStatsDep:
+			a.sysStats.compute()
+		}
+	}
+	a.ensured = a.ensured.union(missing)
+}
+
+// metricValidKind is a runtime copy of runtime/metrics.ValueKind and
+// must be kept structurally identical to that type.
+type metricKind int
+
+const (
+	// These values must be kept identical to their corresponding Kind* values
+	// in the runtime/metrics package.
+	metricKindBad metricKind = iota
+	metricKindUint64
+	metricKindFloat64
+	metricKindFloat64Histogram
+)
+
+// metricSample is a runtime copy of runtime/metrics.Sample and
+// must be kept structurally identical to that type.
+type metricSample struct {
+	name  string
+	value metricValue
+}
+
+// metricValue is a runtime copy of runtime/metrics.Sample and
+// must be kept structurally identical to that type.
+type metricValue struct {
+	kind    metricKind
+	scalar  uint64         // contains scalar values for scalar Kinds.
+	pointer unsafe.Pointer // contains non-scalar values.
+}
+
+// float64HistOrInit tries to pull out an existing float64Histogram
+// from the value, but if none exists, then it allocates one with
+// the given buckets.
+func (v *metricValue) float64HistOrInit(buckets []float64) *metricFloat64Histogram {
+	var hist *metricFloat64Histogram
+	if v.kind == metricKindFloat64Histogram && v.pointer != nil {
+		hist = (*metricFloat64Histogram)(v.pointer)
+	} else {
+		v.kind = metricKindFloat64Histogram
+		hist = new(metricFloat64Histogram)
+		v.pointer = unsafe.Pointer(hist)
+	}
+	hist.buckets = buckets
+	if len(hist.counts) != len(hist.buckets)-1 {
+		hist.counts = make([]uint64, len(buckets)-1)
+	}
+	return hist
+}
+
+// metricFloat64Histogram is a runtime copy of runtime/metrics.Float64Histogram
+// and must be kept structurally identical to that type.
+type metricFloat64Histogram struct {
+	counts  []uint64
+	buckets []float64
+}
+
+// agg is used by readMetrics, and is protected by metricsSema.
+//
+// Managed as a global variable because its pointer will be
+// an argument to a dynamically-defined function, and we'd
+// like to avoid it escaping to the heap.
+var agg statAggregate
+
+// readMetrics is the implementation of runtime/metrics.Read.
+//
+//go:linkname readMetrics runtime/metrics.runtime_readMetrics
+func readMetrics(samplesp unsafe.Pointer, len int, cap int) {
+	// Construct a slice from the args.
+	sl := slice{samplesp, len, cap}
+	samples := *(*[]metricSample)(unsafe.Pointer(&sl))
+
+	metricsLock()
+
+	// Ensure the map is initialized.
+	initMetrics()
+
+	// Clear agg defensively.
+	agg = statAggregate{}
+
+	// Sample.
+	for i := range samples {
+		sample := &samples[i]
+		data, ok := metrics[sample.name]
+		if !ok {
+			sample.value.kind = metricKindBad
+			continue
+		}
+		// Ensure we have all the stats we need.
+		// agg is populated lazily.
+		agg.ensure(&data.deps)
+
+		// Compute the value based on the stats we have.
+		data.compute(&agg, &sample.value)
+	}
+
+	metricsUnlock()
+}
diff --git a/contrib/go/_std_1.19/src/runtime/mfinal.go b/contrib/go/_std_1.19/src/runtime/mfinal.go
new file mode 100644
index 0000000000..f3f3a79fa5
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/mfinal.go
@@ -0,0 +1,491 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Garbage collector: finalizers and block profiling.
+
+package runtime
+
+import (
+	"internal/abi"
+	"internal/goarch"
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+// finblock is an array of finalizers to be executed. finblocks are
+// arranged in a linked list for the finalizer queue.
+//
+// finblock is allocated from non-GC'd memory, so any heap pointers
+// must be specially handled. GC currently assumes that the finalizer
+// queue does not grow during marking (but it can shrink).
+//
+//go:notinheap
+type finblock struct {
+	alllink *finblock
+	next    *finblock
+	cnt     uint32
+	_       int32
+	fin     [(_FinBlockSize - 2*goarch.PtrSize - 2*4) / unsafe.Sizeof(finalizer{})]finalizer
+}
+
+var finlock mutex  // protects the following variables
+var fing *g        // goroutine that runs finalizers
+var finq *finblock // list of finalizers that are to be executed
+var finc *finblock // cache of free blocks
+var finptrmask [_FinBlockSize / goarch.PtrSize / 8]byte
+var fingwait bool
+var fingwake bool
+var allfin *finblock // list of all blocks
+
+// NOTE: Layout known to queuefinalizer.
+type finalizer struct {
+	fn   *funcval       // function to call (may be a heap pointer)
+	arg  unsafe.Pointer // ptr to object (may be a heap pointer)
+	nret uintptr        // bytes of return values from fn
+	fint *_type         // type of first argument of fn
+	ot   *ptrtype       // type of ptr to object (may be a heap pointer)
+}
+
+var finalizer1 = [...]byte{
+	// Each Finalizer is 5 words, ptr ptr INT ptr ptr (INT = uintptr here)
+	// Each byte describes 8 words.
+	// Need 8 Finalizers described by 5 bytes before pattern repeats:
+	//	ptr ptr INT ptr ptr
+	//	ptr ptr INT ptr ptr
+	//	ptr ptr INT ptr ptr
+	//	ptr ptr INT ptr ptr
+	//	ptr ptr INT ptr ptr
+	//	ptr ptr INT ptr ptr
+	//	ptr ptr INT ptr ptr
+	//	ptr ptr INT ptr ptr
+	// aka
+	//
+	//	ptr ptr INT ptr ptr ptr ptr INT
+	//	ptr ptr ptr ptr INT ptr ptr ptr
+	//	ptr INT ptr ptr ptr ptr INT ptr
+	//	ptr ptr ptr INT ptr ptr ptr ptr
+	//	INT ptr ptr ptr ptr INT ptr ptr
+	//
+	// Assumptions about Finalizer layout checked below.
+	1<<0 | 1<<1 | 0<<2 | 1<<3 | 1<<4 | 1<<5 | 1<<6 | 0<<7,
+	1<<0 | 1<<1 | 1<<2 | 1<<3 | 0<<4 | 1<<5 | 1<<6 | 1<<7,
+	1<<0 | 0<<1 | 1<<2 | 1<<3 | 1<<4 | 1<<5 | 0<<6 | 1<<7,
+	1<<0 | 1<<1 | 1<<2 | 0<<3 | 1<<4 | 1<<5 | 1<<6 | 1<<7,
+	0<<0 | 1<<1 | 1<<2 | 1<<3 | 1<<4 | 0<<5 | 1<<6 | 1<<7,
+}
+
+func queuefinalizer(p unsafe.Pointer, fn *funcval, nret uintptr, fint *_type, ot *ptrtype) {
+	if gcphase != _GCoff {
+		// Currently we assume that the finalizer queue won't
+		// grow during marking so we don't have to rescan it
+		// during mark termination. If we ever need to lift
+		// this assumption, we can do it by adding the
+		// necessary barriers to queuefinalizer (which it may
+		// have automatically).
+		throw("queuefinalizer during GC")
+	}
+
+	lock(&finlock)
+	if finq == nil || finq.cnt == uint32(len(finq.fin)) {
+		if finc == nil {
+			finc = (*finblock)(persistentalloc(_FinBlockSize, 0, &memstats.gcMiscSys))
+			finc.alllink = allfin
+			allfin = finc
+			if finptrmask[0] == 0 {
+				// Build pointer mask for Finalizer array in block.
+				// Check assumptions made in finalizer1 array above.
+				if (unsafe.Sizeof(finalizer{}) != 5*goarch.PtrSize ||
+					unsafe.Offsetof(finalizer{}.fn) != 0 ||
+					unsafe.Offsetof(finalizer{}.arg) != goarch.PtrSize ||
+					unsafe.Offsetof(finalizer{}.nret) != 2*goarch.PtrSize ||
+					unsafe.Offsetof(finalizer{}.fint) != 3*goarch.PtrSize ||
+					unsafe.Offsetof(finalizer{}.ot) != 4*goarch.PtrSize) {
+					throw("finalizer out of sync")
+				}
+				for i := range finptrmask {
+					finptrmask[i] = finalizer1[i%len(finalizer1)]
+				}
+			}
+		}
+		block := finc
+		finc = block.next
+		block.next = finq
+		finq = block
+	}
+	f := &finq.fin[finq.cnt]
+	atomic.Xadd(&finq.cnt, +1) // Sync with markroots
+	f.fn = fn
+	f.nret = nret
+	f.fint = fint
+	f.ot = ot
+	f.arg = p
+	fingwake = true
+	unlock(&finlock)
+}
+
+//go:nowritebarrier
+func iterate_finq(callback func(*funcval, unsafe.Pointer, uintptr, *_type, *ptrtype)) {
+	for fb := allfin; fb != nil; fb = fb.alllink {
+		for i := uint32(0); i < fb.cnt; i++ {
+			f := &fb.fin[i]
+			callback(f.fn, f.arg, f.nret, f.fint, f.ot)
+		}
+	}
+}
+
+func wakefing() *g {
+	var res *g
+	lock(&finlock)
+	if fingwait && fingwake {
+		fingwait = false
+		fingwake = false
+		res = fing
+	}
+	unlock(&finlock)
+	return res
+}
+
+var (
+	fingCreate  uint32
+	fingRunning bool
+)
+
+func createfing() {
+	// start the finalizer goroutine exactly once
+	if fingCreate == 0 && atomic.Cas(&fingCreate, 0, 1) {
+		go runfinq()
+	}
+}
+
+// This is the goroutine that runs all of the finalizers
+func runfinq() {
+	var (
+		frame    unsafe.Pointer
+		framecap uintptr
+		argRegs  int
+	)
+
+	gp := getg()
+	lock(&finlock)
+	fing = gp
+	unlock(&finlock)
+
+	for {
+		lock(&finlock)
+		fb := finq
+		finq = nil
+		if fb == nil {
+			fingwait = true
+			goparkunlock(&finlock, waitReasonFinalizerWait, traceEvGoBlock, 1)
+			continue
+		}
+		argRegs = intArgRegs
+		unlock(&finlock)
+		if raceenabled {
+			racefingo()
+		}
+		for fb != nil {
+			for i := fb.cnt; i > 0; i-- {
+				f := &fb.fin[i-1]
+
+				var regs abi.RegArgs
+				// The args may be passed in registers or on stack. Even for
+				// the register case, we still need the spill slots.
+				// TODO: revisit if we remove spill slots.
+				//
+				// Unfortunately because we can have an arbitrary
+				// amount of returns and it would be complex to try and
+				// figure out how many of those can get passed in registers,
+				// just conservatively assume none of them do.
+				framesz := unsafe.Sizeof((any)(nil)) + f.nret
+				if framecap < framesz {
+					// The frame does not contain pointers interesting for GC,
+					// all not yet finalized objects are stored in finq.
+					// If we do not mark it as FlagNoScan,
+					// the last finalized object is not collected.
+					frame = mallocgc(framesz, nil, true)
+					framecap = framesz
+				}
+
+				if f.fint == nil {
+					throw("missing type in runfinq")
+				}
+				r := frame
+				if argRegs > 0 {
+					r = unsafe.Pointer(&regs.Ints)
+				} else {
+					// frame is effectively uninitialized
+					// memory. That means we have to clear
+					// it before writing to it to avoid
+					// confusing the write barrier.
+					*(*[2]uintptr)(frame) = [2]uintptr{}
+				}
+				switch f.fint.kind & kindMask {
+				case kindPtr:
+					// direct use of pointer
+					*(*unsafe.Pointer)(r) = f.arg
+				case kindInterface:
+					ityp := (*interfacetype)(unsafe.Pointer(f.fint))
+					// set up with empty interface
+					(*eface)(r)._type = &f.ot.typ
+					(*eface)(r).data = f.arg
+					if len(ityp.mhdr) != 0 {
+						// convert to interface with methods
+						// this conversion is guaranteed to succeed - we checked in SetFinalizer
+						(*iface)(r).tab = assertE2I(ityp, (*eface)(r)._type)
+					}
+				default:
+					throw("bad kind in runfinq")
+				}
+				fingRunning = true
+				reflectcall(nil, unsafe.Pointer(f.fn), frame, uint32(framesz), uint32(framesz), uint32(framesz), &regs)
+				fingRunning = false
+
+				// Drop finalizer queue heap references
+				// before hiding them from markroot.
+				// This also ensures these will be
+				// clear if we reuse the finalizer.
+				f.fn = nil
+				f.arg = nil
+				f.ot = nil
+				atomic.Store(&fb.cnt, i-1)
+			}
+			next := fb.next
+			lock(&finlock)
+			fb.next = finc
+			finc = fb
+			unlock(&finlock)
+			fb = next
+		}
+	}
+}
+
+// SetFinalizer sets the finalizer associated with obj to the provided
+// finalizer function. When the garbage collector finds an unreachable block
+// with an associated finalizer, it clears the association and runs
+// finalizer(obj) in a separate goroutine. This makes obj reachable again,
+// but now without an associated finalizer. Assuming that SetFinalizer
+// is not called again, the next time the garbage collector sees
+// that obj is unreachable, it will free obj.
+//
+// SetFinalizer(obj, nil) clears any finalizer associated with obj.
+//
+// The argument obj must be a pointer to an object allocated by calling
+// new, by taking the address of a composite literal, or by taking the
+// address of a local variable.
+// The argument finalizer must be a function that takes a single argument
+// to which obj's type can be assigned, and can have arbitrary ignored return
+// values. If either of these is not true, SetFinalizer may abort the
+// program.
+//
+// Finalizers are run in dependency order: if A points at B, both have
+// finalizers, and they are otherwise unreachable, only the finalizer
+// for A runs; once A is freed, the finalizer for B can run.
+// If a cyclic structure includes a block with a finalizer, that
+// cycle is not guaranteed to be garbage collected and the finalizer
+// is not guaranteed to run, because there is no ordering that
+// respects the dependencies.
+//
+// The finalizer is scheduled to run at some arbitrary time after the
+// program can no longer reach the object to which obj points.
+// There is no guarantee that finalizers will run before a program exits,
+// so typically they are useful only for releasing non-memory resources
+// associated with an object during a long-running program.
+// For example, an os.File object could use a finalizer to close the
+// associated operating system file descriptor when a program discards
+// an os.File without calling Close, but it would be a mistake
+// to depend on a finalizer to flush an in-memory I/O buffer such as a
+// bufio.Writer, because the buffer would not be flushed at program exit.
+//
+// It is not guaranteed that a finalizer will run if the size of *obj is
+// zero bytes.
+//
+// It is not guaranteed that a finalizer will run for objects allocated
+// in initializers for package-level variables. Such objects may be
+// linker-allocated, not heap-allocated.
+//
+// A finalizer may run as soon as an object becomes unreachable.
+// In order to use finalizers correctly, the program must ensure that
+// the object is reachable until it is no longer required.
+// Objects stored in global variables, or that can be found by tracing
+// pointers from a global variable, are reachable. For other objects,
+// pass the object to a call of the KeepAlive function to mark the
+// last point in the function where the object must be reachable.
+//
+// For example, if p points to a struct, such as os.File, that contains
+// a file descriptor d, and p has a finalizer that closes that file
+// descriptor, and if the last use of p in a function is a call to
+// syscall.Write(p.d, buf, size), then p may be unreachable as soon as
+// the program enters syscall.Write. The finalizer may run at that moment,
+// closing p.d, causing syscall.Write to fail because it is writing to
+// a closed file descriptor (or, worse, to an entirely different
+// file descriptor opened by a different goroutine). To avoid this problem,
+// call KeepAlive(p) after the call to syscall.Write.
+//
+// A single goroutine runs all finalizers for a program, sequentially.
+// If a finalizer must run for a long time, it should do so by starting
+// a new goroutine.
+//
+// In the terminology of the Go memory model, a call
+// SetFinalizer(x, f) “synchronizes before” the finalization call f(x).
+// However, there is no guarantee that KeepAlive(x) or any other use of x
+// “synchronizes before” f(x), so in general a finalizer should use a mutex
+// or other synchronization mechanism if it needs to access mutable state in x.
+// For example, consider a finalizer that inspects a mutable field in x
+// that is modified from time to time in the main program before x
+// becomes unreachable and the finalizer is invoked.
+// The modifications in the main program and the inspection in the finalizer
+// need to use appropriate synchronization, such as mutexes or atomic updates,
+// to avoid read-write races.
+func SetFinalizer(obj any, finalizer any) {
+	if debug.sbrk != 0 {
+		// debug.sbrk never frees memory, so no finalizers run
+		// (and we don't have the data structures to record them).
+		return
+	}
+	e := efaceOf(&obj)
+	etyp := e._type
+	if etyp == nil {
+		throw("runtime.SetFinalizer: first argument is nil")
+	}
+	if etyp.kind&kindMask != kindPtr {
+		throw("runtime.SetFinalizer: first argument is " + etyp.string() + ", not pointer")
+	}
+	ot := (*ptrtype)(unsafe.Pointer(etyp))
+	if ot.elem == nil {
+		throw("nil elem type!")
+	}
+
+	// find the containing object
+	base, _, _ := findObject(uintptr(e.data), 0, 0)
+
+	if base == 0 {
+		// 0-length objects are okay.
+		if e.data == unsafe.Pointer(&zerobase) {
+			return
+		}
+
+		// Global initializers might be linker-allocated.
+		//	var Foo = &Object{}
+		//	func main() {
+		//		runtime.SetFinalizer(Foo, nil)
+		//	}
+		// The relevant segments are: noptrdata, data, bss, noptrbss.
+		// We cannot assume they are in any order or even contiguous,
+		// due to external linking.
+		for datap := &firstmoduledata; datap != nil; datap = datap.next {
+			if datap.noptrdata <= uintptr(e.data) && uintptr(e.data) < datap.enoptrdata ||
+				datap.data <= uintptr(e.data) && uintptr(e.data) < datap.edata ||
+				datap.bss <= uintptr(e.data) && uintptr(e.data) < datap.ebss ||
+				datap.noptrbss <= uintptr(e.data) && uintptr(e.data) < datap.enoptrbss {
+				return
+			}
+		}
+		throw("runtime.SetFinalizer: pointer not in allocated block")
+	}
+
+	if uintptr(e.data) != base {
+		// As an implementation detail we allow to set finalizers for an inner byte
+		// of an object if it could come from tiny alloc (see mallocgc for details).
+		if ot.elem == nil || ot.elem.ptrdata != 0 || ot.elem.size >= maxTinySize {
+			throw("runtime.SetFinalizer: pointer not at beginning of allocated block")
+		}
+	}
+
+	f := efaceOf(&finalizer)
+	ftyp := f._type
+	if ftyp == nil {
+		// switch to system stack and remove finalizer
+		systemstack(func() {
+			removefinalizer(e.data)
+		})
+		return
+	}
+
+	if ftyp.kind&kindMask != kindFunc {
+		throw("runtime.SetFinalizer: second argument is " + ftyp.string() + ", not a function")
+	}
+	ft := (*functype)(unsafe.Pointer(ftyp))
+	if ft.dotdotdot() {
+		throw("runtime.SetFinalizer: cannot pass " + etyp.string() + " to finalizer " + ftyp.string() + " because dotdotdot")
+	}
+	if ft.inCount != 1 {
+		throw("runtime.SetFinalizer: cannot pass " + etyp.string() + " to finalizer " + ftyp.string())
+	}
+	fint := ft.in()[0]
+	switch {
+	case fint == etyp:
+		// ok - same type
+		goto okarg
+	case fint.kind&kindMask == kindPtr:
+		if (fint.uncommon() == nil || etyp.uncommon() == nil) && (*ptrtype)(unsafe.Pointer(fint)).elem == ot.elem {
+			// ok - not same type, but both pointers,
+			// one or the other is unnamed, and same element type, so assignable.
+			goto okarg
+		}
+	case fint.kind&kindMask == kindInterface:
+		ityp := (*interfacetype)(unsafe.Pointer(fint))
+		if len(ityp.mhdr) == 0 {
+			// ok - satisfies empty interface
+			goto okarg
+		}
+		if iface := assertE2I2(ityp, *efaceOf(&obj)); iface.tab != nil {
+			goto okarg
+		}
+	}
+	throw("runtime.SetFinalizer: cannot pass " + etyp.string() + " to finalizer " + ftyp.string())
+okarg:
+	// compute size needed for return parameters
+	nret := uintptr(0)
+	for _, t := range ft.out() {
+		nret = alignUp(nret, uintptr(t.align)) + uintptr(t.size)
+	}
+	nret = alignUp(nret, goarch.PtrSize)
+
+	// make sure we have a finalizer goroutine
+	createfing()
+
+	systemstack(func() {
+		if !addfinalizer(e.data, (*funcval)(f.data), nret, fint, ot) {
+			throw("runtime.SetFinalizer: finalizer already set")
+		}
+	})
+}
+
+// Mark KeepAlive as noinline so that it is easily detectable as an intrinsic.
+//
+//go:noinline
+
+// KeepAlive marks its argument as currently reachable.
+// This ensures that the object is not freed, and its finalizer is not run,
+// before the point in the program where KeepAlive is called.
+//
+// A very simplified example showing where KeepAlive is required:
+//
+//	type File struct { d int }
+//	d, err := syscall.Open("/file/path", syscall.O_RDONLY, 0)
+//	// ... do something if err != nil ...
+//	p := &File{d}
+//	runtime.SetFinalizer(p, func(p *File) { syscall.Close(p.d) })
+//	var buf [10]byte
+//	n, err := syscall.Read(p.d, buf[:])
+//	// Ensure p is not finalized until Read returns.
+//	runtime.KeepAlive(p)
+//	// No more uses of p after this point.
+//
+// Without the KeepAlive call, the finalizer could run at the start of
+// syscall.Read, closing the file descriptor before syscall.Read makes
+// the actual system call.
+//
+// Note: KeepAlive should only be used to prevent finalizers from
+// running prematurely. In particular, when used with unsafe.Pointer,
+// the rules for valid uses of unsafe.Pointer still apply.
+func KeepAlive(x any) {
+	// Introduce a use of x that the compiler can't eliminate.
+	// This makes sure x is alive on entry. We need x to be alive
+	// on entry for "defer runtime.KeepAlive(x)"; see issue 21402.
+	if cgoAlwaysFalse {
+		println(x)
+	}
+}
diff --git a/contrib/go/_std_1.18/src/runtime/mfixalloc.go b/contrib/go/_std_1.19/src/runtime/mfixalloc.go
index b701a09b40..b701a09b40 100644
--- a/contrib/go/_std_1.18/src/runtime/mfixalloc.go
+++ b/contrib/go/_std_1.19/src/runtime/mfixalloc.go
diff --git a/contrib/go/_std_1.19/src/runtime/mgc.go b/contrib/go/_std_1.19/src/runtime/mgc.go
new file mode 100644
index 0000000000..63e04636d7
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/mgc.go
@@ -0,0 +1,1761 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Garbage collector (GC).
+//
+// The GC runs concurrently with mutator threads, is type accurate (aka precise), allows multiple
+// GC thread to run in parallel. It is a concurrent mark and sweep that uses a write barrier. It is
+// non-generational and non-compacting. Allocation is done using size segregated per P allocation
+// areas to minimize fragmentation while eliminating locks in the common case.
+//
+// The algorithm decomposes into several steps.
+// This is a high level description of the algorithm being used. For an overview of GC a good
+// place to start is Richard Jones' gchandbook.org.
+//
+// The algorithm's intellectual heritage includes Dijkstra's on-the-fly algorithm, see
+// Edsger W. Dijkstra, Leslie Lamport, A. J. Martin, C. S. Scholten, and E. F. M. Steffens. 1978.
+// On-the-fly garbage collection: an exercise in cooperation. Commun. ACM 21, 11 (November 1978),
+// 966-975.
+// For journal quality proofs that these steps are complete, correct, and terminate see
+// Hudson, R., and Moss, J.E.B. Copying Garbage Collection without stopping the world.
+// Concurrency and Computation: Practice and Experience 15(3-5), 2003.
+//
+// 1. GC performs sweep termination.
+//
+//    a. Stop the world. This causes all Ps to reach a GC safe-point.
+//
+//    b. Sweep any unswept spans. There will only be unswept spans if
+//    this GC cycle was forced before the expected time.
+//
+// 2. GC performs the mark phase.
+//
+//    a. Prepare for the mark phase by setting gcphase to _GCmark
+//    (from _GCoff), enabling the write barrier, enabling mutator
+//    assists, and enqueueing root mark jobs. No objects may be
+//    scanned until all Ps have enabled the write barrier, which is
+//    accomplished using STW.
+//
+//    b. Start the world. From this point, GC work is done by mark
+//    workers started by the scheduler and by assists performed as
+//    part of allocation. The write barrier shades both the
+//    overwritten pointer and the new pointer value for any pointer
+//    writes (see mbarrier.go for details). Newly allocated objects
+//    are immediately marked black.
+//
+//    c. GC performs root marking jobs. This includes scanning all
+//    stacks, shading all globals, and shading any heap pointers in
+//    off-heap runtime data structures. Scanning a stack stops a
+//    goroutine, shades any pointers found on its stack, and then
+//    resumes the goroutine.
+//
+//    d. GC drains the work queue of grey objects, scanning each grey
+//    object to black and shading all pointers found in the object
+//    (which in turn may add those pointers to the work queue).
+//
+//    e. Because GC work is spread across local caches, GC uses a
+//    distributed termination algorithm to detect when there are no
+//    more root marking jobs or grey objects (see gcMarkDone). At this
+//    point, GC transitions to mark termination.
+//
+// 3. GC performs mark termination.
+//
+//    a. Stop the world.
+//
+//    b. Set gcphase to _GCmarktermination, and disable workers and
+//    assists.
+//
+//    c. Perform housekeeping like flushing mcaches.
+//
+// 4. GC performs the sweep phase.
+//
+//    a. Prepare for the sweep phase by setting gcphase to _GCoff,
+//    setting up sweep state and disabling the write barrier.
+//
+//    b. Start the world. From this point on, newly allocated objects
+//    are white, and allocating sweeps spans before use if necessary.
+//
+//    c. GC does concurrent sweeping in the background and in response
+//    to allocation. See description below.
+//
+// 5. When sufficient allocation has taken place, replay the sequence
+// starting with 1 above. See discussion of GC rate below.
+
+// Concurrent sweep.
+//
+// The sweep phase proceeds concurrently with normal program execution.
+// The heap is swept span-by-span both lazily (when a goroutine needs another span)
+// and concurrently in a background goroutine (this helps programs that are not CPU bound).
+// At the end of STW mark termination all spans are marked as "needs sweeping".
+//
+// The background sweeper goroutine simply sweeps spans one-by-one.
+//
+// To avoid requesting more OS memory while there are unswept spans, when a
+// goroutine needs another span, it first attempts to reclaim that much memory
+// by sweeping. When a goroutine needs to allocate a new small-object span, it
+// sweeps small-object spans for the same object size until it frees at least
+// one object. When a goroutine needs to allocate large-object span from heap,
+// it sweeps spans until it frees at least that many pages into heap. There is
+// one case where this may not suffice: if a goroutine sweeps and frees two
+// nonadjacent one-page spans to the heap, it will allocate a new two-page
+// span, but there can still be other one-page unswept spans which could be
+// combined into a two-page span.
+//
+// It's critical to ensure that no operations proceed on unswept spans (that would corrupt
+// mark bits in GC bitmap). During GC all mcaches are flushed into the central cache,
+// so they are empty. When a goroutine grabs a new span into mcache, it sweeps it.
+// When a goroutine explicitly frees an object or sets a finalizer, it ensures that
+// the span is swept (either by sweeping it, or by waiting for the concurrent sweep to finish).
+// The finalizer goroutine is kicked off only when all spans are swept.
+// When the next GC starts, it sweeps all not-yet-swept spans (if any).
+
+// GC rate.
+// Next GC is after we've allocated an extra amount of memory proportional to
+// the amount already in use. The proportion is controlled by GOGC environment variable
+// (100 by default). If GOGC=100 and we're using 4M, we'll GC again when we get to 8M
+// (this mark is computed by the gcController.heapGoal method). This keeps the GC cost in
+// linear proportion to the allocation cost. Adjusting GOGC just changes the linear constant
+// (and also the amount of extra memory used).
+
+// Oblets
+//
+// In order to prevent long pauses while scanning large objects and to
+// improve parallelism, the garbage collector breaks up scan jobs for
+// objects larger than maxObletBytes into "oblets" of at most
+// maxObletBytes. When scanning encounters the beginning of a large
+// object, it scans only the first oblet and enqueues the remaining
+// oblets as new scan jobs.
+
+package runtime
+
+import (
+	"internal/cpu"
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+const (
+	_DebugGC         = 0
+	_ConcurrentSweep = true
+	_FinBlockSize    = 4 * 1024
+
+	// debugScanConservative enables debug logging for stack
+	// frames that are scanned conservatively.
+	debugScanConservative = false
+
+	// sweepMinHeapDistance is a lower bound on the heap distance
+	// (in bytes) reserved for concurrent sweeping between GC
+	// cycles.
+	sweepMinHeapDistance = 1024 * 1024
+)
+
+func gcinit() {
+	if unsafe.Sizeof(workbuf{}) != _WorkbufSize {
+		throw("size of Workbuf is suboptimal")
+	}
+	// No sweep on the first cycle.
+	sweep.active.state.Store(sweepDrainedMask)
+
+	// Initialize GC pacer state.
+	// Use the environment variable GOGC for the initial gcPercent value.
+	// Use the environment variable GOMEMLIMIT for the initial memoryLimit value.
+	gcController.init(readGOGC(), readGOMEMLIMIT())
+
+	work.startSema = 1
+	work.markDoneSema = 1
+	lockInit(&work.sweepWaiters.lock, lockRankSweepWaiters)
+	lockInit(&work.assistQueue.lock, lockRankAssistQueue)
+	lockInit(&work.wbufSpans.lock, lockRankWbufSpans)
+}
+
+// gcenable is called after the bulk of the runtime initialization,
+// just before we're about to start letting user code run.
+// It kicks off the background sweeper goroutine, the background
+// scavenger goroutine, and enables GC.
+func gcenable() {
+	// Kick off sweeping and scavenging.
+	c := make(chan int, 2)
+	go bgsweep(c)
+	go bgscavenge(c)
+	<-c
+	<-c
+	memstats.enablegc = true // now that runtime is initialized, GC is okay
+}
+
+// Garbage collector phase.
+// Indicates to write barrier and synchronization task to perform.
+var gcphase uint32
+
+// The compiler knows about this variable.
+// If you change it, you must change builtin/runtime.go, too.
+// If you change the first four bytes, you must also change the write
+// barrier insertion code.
+var writeBarrier struct {
+	enabled bool    // compiler emits a check of this before calling write barrier
+	pad     [3]byte // compiler uses 32-bit load for "enabled" field
+	needed  bool    // whether we need a write barrier for current GC phase
+	cgo     bool    // whether we need a write barrier for a cgo check
+	alignme uint64  // guarantee alignment so that compiler can use a 32 or 64-bit load
+}
+
+// gcBlackenEnabled is 1 if mutator assists and background mark
+// workers are allowed to blacken objects. This must only be set when
+// gcphase == _GCmark.
+var gcBlackenEnabled uint32
+
+const (
+	_GCoff             = iota // GC not running; sweeping in background, write barrier disabled
+	_GCmark                   // GC marking roots and workbufs: allocate black, write barrier ENABLED
+	_GCmarktermination        // GC mark termination: allocate black, P's help GC, write barrier ENABLED
+)
+
+//go:nosplit
+func setGCPhase(x uint32) {
+	atomic.Store(&gcphase, x)
+	writeBarrier.needed = gcphase == _GCmark || gcphase == _GCmarktermination
+	writeBarrier.enabled = writeBarrier.needed || writeBarrier.cgo
+}
+
+// gcMarkWorkerMode represents the mode that a concurrent mark worker
+// should operate in.
+//
+// Concurrent marking happens through four different mechanisms. One
+// is mutator assists, which happen in response to allocations and are
+// not scheduled. The other three are variations in the per-P mark
+// workers and are distinguished by gcMarkWorkerMode.
+type gcMarkWorkerMode int
+
+const (
+	// gcMarkWorkerNotWorker indicates that the next scheduled G is not
+	// starting work and the mode should be ignored.
+	gcMarkWorkerNotWorker gcMarkWorkerMode = iota
+
+	// gcMarkWorkerDedicatedMode indicates that the P of a mark
+	// worker is dedicated to running that mark worker. The mark
+	// worker should run without preemption.
+	gcMarkWorkerDedicatedMode
+
+	// gcMarkWorkerFractionalMode indicates that a P is currently
+	// running the "fractional" mark worker. The fractional worker
+	// is necessary when GOMAXPROCS*gcBackgroundUtilization is not
+	// an integer and using only dedicated workers would result in
+	// utilization too far from the target of gcBackgroundUtilization.
+	// The fractional worker should run until it is preempted and
+	// will be scheduled to pick up the fractional part of
+	// GOMAXPROCS*gcBackgroundUtilization.
+	gcMarkWorkerFractionalMode
+
+	// gcMarkWorkerIdleMode indicates that a P is running the mark
+	// worker because it has nothing else to do. The idle worker
+	// should run until it is preempted and account its time
+	// against gcController.idleMarkTime.
+	gcMarkWorkerIdleMode
+)
+
+// gcMarkWorkerModeStrings are the strings labels of gcMarkWorkerModes
+// to use in execution traces.
+var gcMarkWorkerModeStrings = [...]string{
+	"Not worker",
+	"GC (dedicated)",
+	"GC (fractional)",
+	"GC (idle)",
+}
+
+// pollFractionalWorkerExit reports whether a fractional mark worker
+// should self-preempt. It assumes it is called from the fractional
+// worker.
+func pollFractionalWorkerExit() bool {
+	// This should be kept in sync with the fractional worker
+	// scheduler logic in findRunnableGCWorker.
+	now := nanotime()
+	delta := now - gcController.markStartTime
+	if delta <= 0 {
+		return true
+	}
+	p := getg().m.p.ptr()
+	selfTime := p.gcFractionalMarkTime + (now - p.gcMarkWorkerStartTime)
+	// Add some slack to the utilization goal so that the
+	// fractional worker isn't behind again the instant it exits.
+	return float64(selfTime)/float64(delta) > 1.2*gcController.fractionalUtilizationGoal
+}
+
+var work workType
+
+type workType struct {
+	full  lfstack          // lock-free list of full blocks workbuf
+	empty lfstack          // lock-free list of empty blocks workbuf
+	pad0  cpu.CacheLinePad // prevents false-sharing between full/empty and nproc/nwait
+
+	wbufSpans struct {
+		lock mutex
+		// free is a list of spans dedicated to workbufs, but
+		// that don't currently contain any workbufs.
+		free mSpanList
+		// busy is a list of all spans containing workbufs on
+		// one of the workbuf lists.
+		busy mSpanList
+	}
+
+	// Restore 64-bit alignment on 32-bit.
+	_ uint32
+
+	// bytesMarked is the number of bytes marked this cycle. This
+	// includes bytes blackened in scanned objects, noscan objects
+	// that go straight to black, and permagrey objects scanned by
+	// markroot during the concurrent scan phase. This is updated
+	// atomically during the cycle. Updates may be batched
+	// arbitrarily, since the value is only read at the end of the
+	// cycle.
+	//
+	// Because of benign races during marking, this number may not
+	// be the exact number of marked bytes, but it should be very
+	// close.
+	//
+	// Put this field here because it needs 64-bit atomic access
+	// (and thus 8-byte alignment even on 32-bit architectures).
+	bytesMarked uint64
+
+	markrootNext uint32 // next markroot job
+	markrootJobs uint32 // number of markroot jobs
+
+	nproc  uint32
+	tstart int64
+	nwait  uint32
+
+	// Number of roots of various root types. Set by gcMarkRootPrepare.
+	//
+	// nStackRoots == len(stackRoots), but we have nStackRoots for
+	// consistency.
+	nDataRoots, nBSSRoots, nSpanRoots, nStackRoots int
+
+	// Base indexes of each root type. Set by gcMarkRootPrepare.
+	baseData, baseBSS, baseSpans, baseStacks, baseEnd uint32
+
+	// stackRoots is a snapshot of all of the Gs that existed
+	// before the beginning of concurrent marking. The backing
+	// store of this must not be modified because it might be
+	// shared with allgs.
+	stackRoots []*g
+
+	// Each type of GC state transition is protected by a lock.
+	// Since multiple threads can simultaneously detect the state
+	// transition condition, any thread that detects a transition
+	// condition must acquire the appropriate transition lock,
+	// re-check the transition condition and return if it no
+	// longer holds or perform the transition if it does.
+	// Likewise, any transition must invalidate the transition
+	// condition before releasing the lock. This ensures that each
+	// transition is performed by exactly one thread and threads
+	// that need the transition to happen block until it has
+	// happened.
+	//
+	// startSema protects the transition from "off" to mark or
+	// mark termination.
+	startSema uint32
+	// markDoneSema protects transitions from mark to mark termination.
+	markDoneSema uint32
+
+	bgMarkReady note   // signal background mark worker has started
+	bgMarkDone  uint32 // cas to 1 when at a background mark completion point
+	// Background mark completion signaling
+
+	// mode is the concurrency mode of the current GC cycle.
+	mode gcMode
+
+	// userForced indicates the current GC cycle was forced by an
+	// explicit user call.
+	userForced bool
+
+	// totaltime is the CPU nanoseconds spent in GC since the
+	// program started if debug.gctrace > 0.
+	totaltime int64
+
+	// initialHeapLive is the value of gcController.heapLive at the
+	// beginning of this GC cycle.
+	initialHeapLive uint64
+
+	// assistQueue is a queue of assists that are blocked because
+	// there was neither enough credit to steal or enough work to
+	// do.
+	assistQueue struct {
+		lock mutex
+		q    gQueue
+	}
+
+	// sweepWaiters is a list of blocked goroutines to wake when
+	// we transition from mark termination to sweep.
+	sweepWaiters struct {
+		lock mutex
+		list gList
+	}
+
+	// cycles is the number of completed GC cycles, where a GC
+	// cycle is sweep termination, mark, mark termination, and
+	// sweep. This differs from memstats.numgc, which is
+	// incremented at mark termination.
+	cycles uint32
+
+	// Timing/utilization stats for this cycle.
+	stwprocs, maxprocs                 int32
+	tSweepTerm, tMark, tMarkTerm, tEnd int64 // nanotime() of phase start
+
+	pauseNS    int64 // total STW time this cycle
+	pauseStart int64 // nanotime() of last STW
+
+	// debug.gctrace heap sizes for this cycle.
+	heap0, heap1, heap2 uint64
+}
+
+// GC runs a garbage collection and blocks the caller until the
+// garbage collection is complete. It may also block the entire
+// program.
+func GC() {
+	// We consider a cycle to be: sweep termination, mark, mark
+	// termination, and sweep. This function shouldn't return
+	// until a full cycle has been completed, from beginning to
+	// end. Hence, we always want to finish up the current cycle
+	// and start a new one. That means:
+	//
+	// 1. In sweep termination, mark, or mark termination of cycle
+	// N, wait until mark termination N completes and transitions
+	// to sweep N.
+	//
+	// 2. In sweep N, help with sweep N.
+	//
+	// At this point we can begin a full cycle N+1.
+	//
+	// 3. Trigger cycle N+1 by starting sweep termination N+1.
+	//
+	// 4. Wait for mark termination N+1 to complete.
+	//
+	// 5. Help with sweep N+1 until it's done.
+	//
+	// This all has to be written to deal with the fact that the
+	// GC may move ahead on its own. For example, when we block
+	// until mark termination N, we may wake up in cycle N+2.
+
+	// Wait until the current sweep termination, mark, and mark
+	// termination complete.
+	n := atomic.Load(&work.cycles)
+	gcWaitOnMark(n)
+
+	// We're now in sweep N or later. Trigger GC cycle N+1, which
+	// will first finish sweep N if necessary and then enter sweep
+	// termination N+1.
+	gcStart(gcTrigger{kind: gcTriggerCycle, n: n + 1})
+
+	// Wait for mark termination N+1 to complete.
+	gcWaitOnMark(n + 1)
+
+	// Finish sweep N+1 before returning. We do this both to
+	// complete the cycle and because runtime.GC() is often used
+	// as part of tests and benchmarks to get the system into a
+	// relatively stable and isolated state.
+	for atomic.Load(&work.cycles) == n+1 && sweepone() != ^uintptr(0) {
+		sweep.nbgsweep++
+		Gosched()
+	}
+
+	// Callers may assume that the heap profile reflects the
+	// just-completed cycle when this returns (historically this
+	// happened because this was a STW GC), but right now the
+	// profile still reflects mark termination N, not N+1.
+	//
+	// As soon as all of the sweep frees from cycle N+1 are done,
+	// we can go ahead and publish the heap profile.
+	//
+	// First, wait for sweeping to finish. (We know there are no
+	// more spans on the sweep queue, but we may be concurrently
+	// sweeping spans, so we have to wait.)
+	for atomic.Load(&work.cycles) == n+1 && !isSweepDone() {
+		Gosched()
+	}
+
+	// Now we're really done with sweeping, so we can publish the
+	// stable heap profile. Only do this if we haven't already hit
+	// another mark termination.
+	mp := acquirem()
+	cycle := atomic.Load(&work.cycles)
+	if cycle == n+1 || (gcphase == _GCmark && cycle == n+2) {
+		mProf_PostSweep()
+	}
+	releasem(mp)
+}
+
+// gcWaitOnMark blocks until GC finishes the Nth mark phase. If GC has
+// already completed this mark phase, it returns immediately.
+func gcWaitOnMark(n uint32) {
+	for {
+		// Disable phase transitions.
+		lock(&work.sweepWaiters.lock)
+		nMarks := atomic.Load(&work.cycles)
+		if gcphase != _GCmark {
+			// We've already completed this cycle's mark.
+			nMarks++
+		}
+		if nMarks > n {
+			// We're done.
+			unlock(&work.sweepWaiters.lock)
+			return
+		}
+
+		// Wait until sweep termination, mark, and mark
+		// termination of cycle N complete.
+		work.sweepWaiters.list.push(getg())
+		goparkunlock(&work.sweepWaiters.lock, waitReasonWaitForGCCycle, traceEvGoBlock, 1)
+	}
+}
+
+// gcMode indicates how concurrent a GC cycle should be.
+type gcMode int
+
+const (
+	gcBackgroundMode gcMode = iota // concurrent GC and sweep
+	gcForceMode                    // stop-the-world GC now, concurrent sweep
+	gcForceBlockMode               // stop-the-world GC now and STW sweep (forced by user)
+)
+
+// A gcTrigger is a predicate for starting a GC cycle. Specifically,
+// it is an exit condition for the _GCoff phase.
+type gcTrigger struct {
+	kind gcTriggerKind
+	now  int64  // gcTriggerTime: current time
+	n    uint32 // gcTriggerCycle: cycle number to start
+}
+
+type gcTriggerKind int
+
+const (
+	// gcTriggerHeap indicates that a cycle should be started when
+	// the heap size reaches the trigger heap size computed by the
+	// controller.
+	gcTriggerHeap gcTriggerKind = iota
+
+	// gcTriggerTime indicates that a cycle should be started when
+	// it's been more than forcegcperiod nanoseconds since the
+	// previous GC cycle.
+	gcTriggerTime
+
+	// gcTriggerCycle indicates that a cycle should be started if
+	// we have not yet started cycle number gcTrigger.n (relative
+	// to work.cycles).
+	gcTriggerCycle
+)
+
+// test reports whether the trigger condition is satisfied, meaning
+// that the exit condition for the _GCoff phase has been met. The exit
+// condition should be tested when allocating.
+func (t gcTrigger) test() bool {
+	if !memstats.enablegc || panicking != 0 || gcphase != _GCoff {
+		return false
+	}
+	switch t.kind {
+	case gcTriggerHeap:
+		// Non-atomic access to gcController.heapLive for performance. If
+		// we are going to trigger on this, this thread just
+		// atomically wrote gcController.heapLive anyway and we'll see our
+		// own write.
+		trigger, _ := gcController.trigger()
+		return atomic.Load64(&gcController.heapLive) >= trigger
+	case gcTriggerTime:
+		if gcController.gcPercent.Load() < 0 {
+			return false
+		}
+		lastgc := int64(atomic.Load64(&memstats.last_gc_nanotime))
+		return lastgc != 0 && t.now-lastgc > forcegcperiod
+	case gcTriggerCycle:
+		// t.n > work.cycles, but accounting for wraparound.
+		return int32(t.n-work.cycles) > 0
+	}
+	return true
+}
+
+// gcStart starts the GC. It transitions from _GCoff to _GCmark (if
+// debug.gcstoptheworld == 0) or performs all of GC (if
+// debug.gcstoptheworld != 0).
+//
+// This may return without performing this transition in some cases,
+// such as when called on a system stack or with locks held.
+func gcStart(trigger gcTrigger) {
+	// Since this is called from malloc and malloc is called in
+	// the guts of a number of libraries that might be holding
+	// locks, don't attempt to start GC in non-preemptible or
+	// potentially unstable situations.
+	mp := acquirem()
+	if gp := getg(); gp == mp.g0 || mp.locks > 1 || mp.preemptoff != "" {
+		releasem(mp)
+		return
+	}
+	releasem(mp)
+	mp = nil
+
+	// Pick up the remaining unswept/not being swept spans concurrently
+	//
+	// This shouldn't happen if we're being invoked in background
+	// mode since proportional sweep should have just finished
+	// sweeping everything, but rounding errors, etc, may leave a
+	// few spans unswept. In forced mode, this is necessary since
+	// GC can be forced at any point in the sweeping cycle.
+	//
+	// We check the transition condition continuously here in case
+	// this G gets delayed in to the next GC cycle.
+	for trigger.test() && sweepone() != ^uintptr(0) {
+		sweep.nbgsweep++
+	}
+
+	// Perform GC initialization and the sweep termination
+	// transition.
+	semacquire(&work.startSema)
+	// Re-check transition condition under transition lock.
+	if !trigger.test() {
+		semrelease(&work.startSema)
+		return
+	}
+
+	// For stats, check if this GC was forced by the user.
+	work.userForced = trigger.kind == gcTriggerCycle
+
+	// In gcstoptheworld debug mode, upgrade the mode accordingly.
+	// We do this after re-checking the transition condition so
+	// that multiple goroutines that detect the heap trigger don't
+	// start multiple STW GCs.
+	mode := gcBackgroundMode
+	if debug.gcstoptheworld == 1 {
+		mode = gcForceMode
+	} else if debug.gcstoptheworld == 2 {
+		mode = gcForceBlockMode
+	}
+
+	// Ok, we're doing it! Stop everybody else
+	semacquire(&gcsema)
+	semacquire(&worldsema)
+
+	if trace.enabled {
+		traceGCStart()
+	}
+
+	// Check that all Ps have finished deferred mcache flushes.
+	for _, p := range allp {
+		if fg := atomic.Load(&p.mcache.flushGen); fg != mheap_.sweepgen {
+			println("runtime: p", p.id, "flushGen", fg, "!= sweepgen", mheap_.sweepgen)
+			throw("p mcache not flushed")
+		}
+	}
+
+	gcBgMarkStartWorkers()
+
+	systemstack(gcResetMarkState)
+
+	work.stwprocs, work.maxprocs = gomaxprocs, gomaxprocs
+	if work.stwprocs > ncpu {
+		// This is used to compute CPU time of the STW phases,
+		// so it can't be more than ncpu, even if GOMAXPROCS is.
+		work.stwprocs = ncpu
+	}
+	work.heap0 = atomic.Load64(&gcController.heapLive)
+	work.pauseNS = 0
+	work.mode = mode
+
+	now := nanotime()
+	work.tSweepTerm = now
+	work.pauseStart = now
+	if trace.enabled {
+		traceGCSTWStart(1)
+	}
+	systemstack(stopTheWorldWithSema)
+	// Finish sweep before we start concurrent scan.
+	systemstack(func() {
+		finishsweep_m()
+	})
+
+	// clearpools before we start the GC. If we wait they memory will not be
+	// reclaimed until the next GC cycle.
+	clearpools()
+
+	work.cycles++
+
+	// Assists and workers can start the moment we start
+	// the world.
+	gcController.startCycle(now, int(gomaxprocs), trigger)
+
+	// Notify the CPU limiter that assists may begin.
+	gcCPULimiter.startGCTransition(true, now)
+
+	// In STW mode, disable scheduling of user Gs. This may also
+	// disable scheduling of this goroutine, so it may block as
+	// soon as we start the world again.
+	if mode != gcBackgroundMode {
+		schedEnableUser(false)
+	}
+
+	// Enter concurrent mark phase and enable
+	// write barriers.
+	//
+	// Because the world is stopped, all Ps will
+	// observe that write barriers are enabled by
+	// the time we start the world and begin
+	// scanning.
+	//
+	// Write barriers must be enabled before assists are
+	// enabled because they must be enabled before
+	// any non-leaf heap objects are marked. Since
+	// allocations are blocked until assists can
+	// happen, we want enable assists as early as
+	// possible.
+	setGCPhase(_GCmark)
+
+	gcBgMarkPrepare() // Must happen before assist enable.
+	gcMarkRootPrepare()
+
+	// Mark all active tinyalloc blocks. Since we're
+	// allocating from these, they need to be black like
+	// other allocations. The alternative is to blacken
+	// the tiny block on every allocation from it, which
+	// would slow down the tiny allocator.
+	gcMarkTinyAllocs()
+
+	// At this point all Ps have enabled the write
+	// barrier, thus maintaining the no white to
+	// black invariant. Enable mutator assists to
+	// put back-pressure on fast allocating
+	// mutators.
+	atomic.Store(&gcBlackenEnabled, 1)
+
+	// In STW mode, we could block the instant systemstack
+	// returns, so make sure we're not preemptible.
+	mp = acquirem()
+
+	// Concurrent mark.
+	systemstack(func() {
+		now = startTheWorldWithSema(trace.enabled)
+		work.pauseNS += now - work.pauseStart
+		work.tMark = now
+		memstats.gcPauseDist.record(now - work.pauseStart)
+
+		// Release the CPU limiter.
+		gcCPULimiter.finishGCTransition(now)
+	})
+
+	// Release the world sema before Gosched() in STW mode
+	// because we will need to reacquire it later but before
+	// this goroutine becomes runnable again, and we could
+	// self-deadlock otherwise.
+	semrelease(&worldsema)
+	releasem(mp)
+
+	// Make sure we block instead of returning to user code
+	// in STW mode.
+	if mode != gcBackgroundMode {
+		Gosched()
+	}
+
+	semrelease(&work.startSema)
+}
+
+// gcMarkDoneFlushed counts the number of P's with flushed work.
+//
+// Ideally this would be a captured local in gcMarkDone, but forEachP
+// escapes its callback closure, so it can't capture anything.
+//
+// This is protected by markDoneSema.
+var gcMarkDoneFlushed uint32
+
+// gcMarkDone transitions the GC from mark to mark termination if all
+// reachable objects have been marked (that is, there are no grey
+// objects and can be no more in the future). Otherwise, it flushes
+// all local work to the global queues where it can be discovered by
+// other workers.
+//
+// This should be called when all local mark work has been drained and
+// there are no remaining workers. Specifically, when
+//
+//	work.nwait == work.nproc && !gcMarkWorkAvailable(p)
+//
+// The calling context must be preemptible.
+//
+// Flushing local work is important because idle Ps may have local
+// work queued. This is the only way to make that work visible and
+// drive GC to completion.
+//
+// It is explicitly okay to have write barriers in this function. If
+// it does transition to mark termination, then all reachable objects
+// have been marked, so the write barrier cannot shade any more
+// objects.
+func gcMarkDone() {
+	// Ensure only one thread is running the ragged barrier at a
+	// time.
+	semacquire(&work.markDoneSema)
+
+top:
+	// Re-check transition condition under transition lock.
+	//
+	// It's critical that this checks the global work queues are
+	// empty before performing the ragged barrier. Otherwise,
+	// there could be global work that a P could take after the P
+	// has passed the ragged barrier.
+	if !(gcphase == _GCmark && work.nwait == work.nproc && !gcMarkWorkAvailable(nil)) {
+		semrelease(&work.markDoneSema)
+		return
+	}
+
+	// forEachP needs worldsema to execute, and we'll need it to
+	// stop the world later, so acquire worldsema now.
+	semacquire(&worldsema)
+
+	// Flush all local buffers and collect flushedWork flags.
+	gcMarkDoneFlushed = 0
+	systemstack(func() {
+		gp := getg().m.curg
+		// Mark the user stack as preemptible so that it may be scanned.
+		// Otherwise, our attempt to force all P's to a safepoint could
+		// result in a deadlock as we attempt to preempt a worker that's
+		// trying to preempt us (e.g. for a stack scan).
+		casgstatus(gp, _Grunning, _Gwaiting)
+		forEachP(func(_p_ *p) {
+			// Flush the write barrier buffer, since this may add
+			// work to the gcWork.
+			wbBufFlush1(_p_)
+
+			// Flush the gcWork, since this may create global work
+			// and set the flushedWork flag.
+			//
+			// TODO(austin): Break up these workbufs to
+			// better distribute work.
+			_p_.gcw.dispose()
+			// Collect the flushedWork flag.
+			if _p_.gcw.flushedWork {
+				atomic.Xadd(&gcMarkDoneFlushed, 1)
+				_p_.gcw.flushedWork = false
+			}
+		})
+		casgstatus(gp, _Gwaiting, _Grunning)
+	})
+
+	if gcMarkDoneFlushed != 0 {
+		// More grey objects were discovered since the
+		// previous termination check, so there may be more
+		// work to do. Keep going. It's possible the
+		// transition condition became true again during the
+		// ragged barrier, so re-check it.
+		semrelease(&worldsema)
+		goto top
+	}
+
+	// There was no global work, no local work, and no Ps
+	// communicated work since we took markDoneSema. Therefore
+	// there are no grey objects and no more objects can be
+	// shaded. Transition to mark termination.
+	now := nanotime()
+	work.tMarkTerm = now
+	work.pauseStart = now
+	getg().m.preemptoff = "gcing"
+	if trace.enabled {
+		traceGCSTWStart(0)
+	}
+	systemstack(stopTheWorldWithSema)
+	// The gcphase is _GCmark, it will transition to _GCmarktermination
+	// below. The important thing is that the wb remains active until
+	// all marking is complete. This includes writes made by the GC.
+
+	// There is sometimes work left over when we enter mark termination due
+	// to write barriers performed after the completion barrier above.
+	// Detect this and resume concurrent mark. This is obviously
+	// unfortunate.
+	//
+	// See issue #27993 for details.
+	//
+	// Switch to the system stack to call wbBufFlush1, though in this case
+	// it doesn't matter because we're non-preemptible anyway.
+	restart := false
+	systemstack(func() {
+		for _, p := range allp {
+			wbBufFlush1(p)
+			if !p.gcw.empty() {
+				restart = true
+				break
+			}
+		}
+	})
+	if restart {
+		getg().m.preemptoff = ""
+		systemstack(func() {
+			now := startTheWorldWithSema(true)
+			work.pauseNS += now - work.pauseStart
+			memstats.gcPauseDist.record(now - work.pauseStart)
+		})
+		semrelease(&worldsema)
+		goto top
+	}
+
+	gcComputeStartingStackSize()
+
+	// Disable assists and background workers. We must do
+	// this before waking blocked assists.
+	atomic.Store(&gcBlackenEnabled, 0)
+
+	// Notify the CPU limiter that GC assists will now cease.
+	gcCPULimiter.startGCTransition(false, now)
+
+	// Wake all blocked assists. These will run when we
+	// start the world again.
+	gcWakeAllAssists()
+
+	// Likewise, release the transition lock. Blocked
+	// workers and assists will run when we start the
+	// world again.
+	semrelease(&work.markDoneSema)
+
+	// In STW mode, re-enable user goroutines. These will be
+	// queued to run after we start the world.
+	schedEnableUser(true)
+
+	// endCycle depends on all gcWork cache stats being flushed.
+	// The termination algorithm above ensured that up to
+	// allocations since the ragged barrier.
+	gcController.endCycle(now, int(gomaxprocs), work.userForced)
+
+	// Perform mark termination. This will restart the world.
+	gcMarkTermination()
+}
+
+// World must be stopped and mark assists and background workers must be
+// disabled.
+func gcMarkTermination() {
+	// Start marktermination (write barrier remains enabled for now).
+	setGCPhase(_GCmarktermination)
+
+	work.heap1 = gcController.heapLive
+	startTime := nanotime()
+
+	mp := acquirem()
+	mp.preemptoff = "gcing"
+	_g_ := getg()
+	_g_.m.traceback = 2
+	gp := _g_.m.curg
+	casgstatus(gp, _Grunning, _Gwaiting)
+	gp.waitreason = waitReasonGarbageCollection
+
+	// Run gc on the g0 stack. We do this so that the g stack
+	// we're currently running on will no longer change. Cuts
+	// the root set down a bit (g0 stacks are not scanned, and
+	// we don't need to scan gc's internal state).  We also
+	// need to switch to g0 so we can shrink the stack.
+	systemstack(func() {
+		gcMark(startTime)
+		// Must return immediately.
+		// The outer function's stack may have moved
+		// during gcMark (it shrinks stacks, including the
+		// outer function's stack), so we must not refer
+		// to any of its variables. Return back to the
+		// non-system stack to pick up the new addresses
+		// before continuing.
+	})
+
+	systemstack(func() {
+		work.heap2 = work.bytesMarked
+		if debug.gccheckmark > 0 {
+			// Run a full non-parallel, stop-the-world
+			// mark using checkmark bits, to check that we
+			// didn't forget to mark anything during the
+			// concurrent mark process.
+			startCheckmarks()
+			gcResetMarkState()
+			gcw := &getg().m.p.ptr().gcw
+			gcDrain(gcw, 0)
+			wbBufFlush1(getg().m.p.ptr())
+			gcw.dispose()
+			endCheckmarks()
+		}
+
+		// marking is complete so we can turn the write barrier off
+		setGCPhase(_GCoff)
+		gcSweep(work.mode)
+	})
+
+	_g_.m.traceback = 0
+	casgstatus(gp, _Gwaiting, _Grunning)
+
+	if trace.enabled {
+		traceGCDone()
+	}
+
+	// all done
+	mp.preemptoff = ""
+
+	if gcphase != _GCoff {
+		throw("gc done but gcphase != _GCoff")
+	}
+
+	// Record heapInUse for scavenger.
+	memstats.lastHeapInUse = gcController.heapInUse.load()
+
+	// Update GC trigger and pacing, as well as downstream consumers
+	// of this pacing information, for the next cycle.
+	systemstack(gcControllerCommit)
+
+	// Update timing memstats
+	now := nanotime()
+	sec, nsec, _ := time_now()
+	unixNow := sec*1e9 + int64(nsec)
+	work.pauseNS += now - work.pauseStart
+	work.tEnd = now
+	memstats.gcPauseDist.record(now - work.pauseStart)
+	atomic.Store64(&memstats.last_gc_unix, uint64(unixNow)) // must be Unix time to make sense to user
+	atomic.Store64(&memstats.last_gc_nanotime, uint64(now)) // monotonic time for us
+	memstats.pause_ns[memstats.numgc%uint32(len(memstats.pause_ns))] = uint64(work.pauseNS)
+	memstats.pause_end[memstats.numgc%uint32(len(memstats.pause_end))] = uint64(unixNow)
+	memstats.pause_total_ns += uint64(work.pauseNS)
+
+	// Update work.totaltime.
+	sweepTermCpu := int64(work.stwprocs) * (work.tMark - work.tSweepTerm)
+	// We report idle marking time below, but omit it from the
+	// overall utilization here since it's "free".
+	markCpu := gcController.assistTime.Load() + gcController.dedicatedMarkTime + gcController.fractionalMarkTime
+	markTermCpu := int64(work.stwprocs) * (work.tEnd - work.tMarkTerm)
+	cycleCpu := sweepTermCpu + markCpu + markTermCpu
+	work.totaltime += cycleCpu
+
+	// Compute overall GC CPU utilization.
+	totalCpu := sched.totaltime + (now-sched.procresizetime)*int64(gomaxprocs)
+	memstats.gc_cpu_fraction = float64(work.totaltime) / float64(totalCpu)
+
+	// Reset assist time stat.
+	//
+	// Do this now, instead of at the start of the next GC cycle, because
+	// these two may keep accumulating even if the GC is not active.
+	mheap_.pages.scav.assistTime.Store(0)
+
+	// Reset sweep state.
+	sweep.nbgsweep = 0
+	sweep.npausesweep = 0
+
+	if work.userForced {
+		memstats.numforcedgc++
+	}
+
+	// Bump GC cycle count and wake goroutines waiting on sweep.
+	lock(&work.sweepWaiters.lock)
+	memstats.numgc++
+	injectglist(&work.sweepWaiters.list)
+	unlock(&work.sweepWaiters.lock)
+
+	// Release the CPU limiter.
+	gcCPULimiter.finishGCTransition(now)
+
+	// Finish the current heap profiling cycle and start a new
+	// heap profiling cycle. We do this before starting the world
+	// so events don't leak into the wrong cycle.
+	mProf_NextCycle()
+
+	// There may be stale spans in mcaches that need to be swept.
+	// Those aren't tracked in any sweep lists, so we need to
+	// count them against sweep completion until we ensure all
+	// those spans have been forced out.
+	sl := sweep.active.begin()
+	if !sl.valid {
+		throw("failed to set sweep barrier")
+	}
+
+	systemstack(func() { startTheWorldWithSema(true) })
+
+	// Flush the heap profile so we can start a new cycle next GC.
+	// This is relatively expensive, so we don't do it with the
+	// world stopped.
+	mProf_Flush()
+
+	// Prepare workbufs for freeing by the sweeper. We do this
+	// asynchronously because it can take non-trivial time.
+	prepareFreeWorkbufs()
+
+	// Free stack spans. This must be done between GC cycles.
+	systemstack(freeStackSpans)
+
+	// Ensure all mcaches are flushed. Each P will flush its own
+	// mcache before allocating, but idle Ps may not. Since this
+	// is necessary to sweep all spans, we need to ensure all
+	// mcaches are flushed before we start the next GC cycle.
+	systemstack(func() {
+		forEachP(func(_p_ *p) {
+			_p_.mcache.prepareForSweep()
+		})
+	})
+	// Now that we've swept stale spans in mcaches, they don't
+	// count against unswept spans.
+	sweep.active.end(sl)
+
+	// Print gctrace before dropping worldsema. As soon as we drop
+	// worldsema another cycle could start and smash the stats
+	// we're trying to print.
+	if debug.gctrace > 0 {
+		util := int(memstats.gc_cpu_fraction * 100)
+
+		var sbuf [24]byte
+		printlock()
+		print("gc ", memstats.numgc,
+			" @", string(itoaDiv(sbuf[:], uint64(work.tSweepTerm-runtimeInitTime)/1e6, 3)), "s ",
+			util, "%: ")
+		prev := work.tSweepTerm
+		for i, ns := range []int64{work.tMark, work.tMarkTerm, work.tEnd} {
+			if i != 0 {
+				print("+")
+			}
+			print(string(fmtNSAsMS(sbuf[:], uint64(ns-prev))))
+			prev = ns
+		}
+		print(" ms clock, ")
+		for i, ns := range []int64{
+			sweepTermCpu,
+			gcController.assistTime.Load(),
+			gcController.dedicatedMarkTime + gcController.fractionalMarkTime,
+			gcController.idleMarkTime,
+			markTermCpu,
+		} {
+			if i == 2 || i == 3 {
+				// Separate mark time components with /.
+				print("/")
+			} else if i != 0 {
+				print("+")
+			}
+			print(string(fmtNSAsMS(sbuf[:], uint64(ns))))
+		}
+		print(" ms cpu, ",
+			work.heap0>>20, "->", work.heap1>>20, "->", work.heap2>>20, " MB, ",
+			gcController.lastHeapGoal>>20, " MB goal, ",
+			atomic.Load64(&gcController.maxStackScan)>>20, " MB stacks, ",
+			gcController.globalsScan>>20, " MB globals, ",
+			work.maxprocs, " P")
+		if work.userForced {
+			print(" (forced)")
+		}
+		print("\n")
+		printunlock()
+	}
+
+	semrelease(&worldsema)
+	semrelease(&gcsema)
+	// Careful: another GC cycle may start now.
+
+	releasem(mp)
+	mp = nil
+
+	// now that gc is done, kick off finalizer thread if needed
+	if !concurrentSweep {
+		// give the queued finalizers, if any, a chance to run
+		Gosched()
+	}
+}
+
+// gcBgMarkStartWorkers prepares background mark worker goroutines. These
+// goroutines will not run until the mark phase, but they must be started while
+// the work is not stopped and from a regular G stack. The caller must hold
+// worldsema.
+func gcBgMarkStartWorkers() {
+	// Background marking is performed by per-P G's. Ensure that each P has
+	// a background GC G.
+	//
+	// Worker Gs don't exit if gomaxprocs is reduced. If it is raised
+	// again, we can reuse the old workers; no need to create new workers.
+	for gcBgMarkWorkerCount < gomaxprocs {
+		go gcBgMarkWorker()
+
+		notetsleepg(&work.bgMarkReady, -1)
+		noteclear(&work.bgMarkReady)
+		// The worker is now guaranteed to be added to the pool before
+		// its P's next findRunnableGCWorker.
+
+		gcBgMarkWorkerCount++
+	}
+}
+
+// gcBgMarkPrepare sets up state for background marking.
+// Mutator assists must not yet be enabled.
+func gcBgMarkPrepare() {
+	// Background marking will stop when the work queues are empty
+	// and there are no more workers (note that, since this is
+	// concurrent, this may be a transient state, but mark
+	// termination will clean it up). Between background workers
+	// and assists, we don't really know how many workers there
+	// will be, so we pretend to have an arbitrarily large number
+	// of workers, almost all of which are "waiting". While a
+	// worker is working it decrements nwait. If nproc == nwait,
+	// there are no workers.
+	work.nproc = ^uint32(0)
+	work.nwait = ^uint32(0)
+}
+
+// gcBgMarkWorker is an entry in the gcBgMarkWorkerPool. It points to a single
+// gcBgMarkWorker goroutine.
+type gcBgMarkWorkerNode struct {
+	// Unused workers are managed in a lock-free stack. This field must be first.
+	node lfnode
+
+	// The g of this worker.
+	gp guintptr
+
+	// Release this m on park. This is used to communicate with the unlock
+	// function, which cannot access the G's stack. It is unused outside of
+	// gcBgMarkWorker().
+	m muintptr
+}
+
+func gcBgMarkWorker() {
+	gp := getg()
+
+	// We pass node to a gopark unlock function, so it can't be on
+	// the stack (see gopark). Prevent deadlock from recursively
+	// starting GC by disabling preemption.
+	gp.m.preemptoff = "GC worker init"
+	node := new(gcBgMarkWorkerNode)
+	gp.m.preemptoff = ""
+
+	node.gp.set(gp)
+
+	node.m.set(acquirem())
+	notewakeup(&work.bgMarkReady)
+	// After this point, the background mark worker is generally scheduled
+	// cooperatively by gcController.findRunnableGCWorker. While performing
+	// work on the P, preemption is disabled because we are working on
+	// P-local work buffers. When the preempt flag is set, this puts itself
+	// into _Gwaiting to be woken up by gcController.findRunnableGCWorker
+	// at the appropriate time.
+	//
+	// When preemption is enabled (e.g., while in gcMarkDone), this worker
+	// may be preempted and schedule as a _Grunnable G from a runq. That is
+	// fine; it will eventually gopark again for further scheduling via
+	// findRunnableGCWorker.
+	//
+	// Since we disable preemption before notifying bgMarkReady, we
+	// guarantee that this G will be in the worker pool for the next
+	// findRunnableGCWorker. This isn't strictly necessary, but it reduces
+	// latency between _GCmark starting and the workers starting.
+
+	for {
+		// Go to sleep until woken by
+		// gcController.findRunnableGCWorker.
+		gopark(func(g *g, nodep unsafe.Pointer) bool {
+			node := (*gcBgMarkWorkerNode)(nodep)
+
+			if mp := node.m.ptr(); mp != nil {
+				// The worker G is no longer running; release
+				// the M.
+				//
+				// N.B. it is _safe_ to release the M as soon
+				// as we are no longer performing P-local mark
+				// work.
+				//
+				// However, since we cooperatively stop work
+				// when gp.preempt is set, if we releasem in
+				// the loop then the following call to gopark
+				// would immediately preempt the G. This is
+				// also safe, but inefficient: the G must
+				// schedule again only to enter gopark and park
+				// again. Thus, we defer the release until
+				// after parking the G.
+				releasem(mp)
+			}
+
+			// Release this G to the pool.
+			gcBgMarkWorkerPool.push(&node.node)
+			// Note that at this point, the G may immediately be
+			// rescheduled and may be running.
+			return true
+		}, unsafe.Pointer(node), waitReasonGCWorkerIdle, traceEvGoBlock, 0)
+
+		// Preemption must not occur here, or another G might see
+		// p.gcMarkWorkerMode.
+
+		// Disable preemption so we can use the gcw. If the
+		// scheduler wants to preempt us, we'll stop draining,
+		// dispose the gcw, and then preempt.
+		node.m.set(acquirem())
+		pp := gp.m.p.ptr() // P can't change with preemption disabled.
+
+		if gcBlackenEnabled == 0 {
+			println("worker mode", pp.gcMarkWorkerMode)
+			throw("gcBgMarkWorker: blackening not enabled")
+		}
+
+		if pp.gcMarkWorkerMode == gcMarkWorkerNotWorker {
+			throw("gcBgMarkWorker: mode not set")
+		}
+
+		startTime := nanotime()
+		pp.gcMarkWorkerStartTime = startTime
+		var trackLimiterEvent bool
+		if pp.gcMarkWorkerMode == gcMarkWorkerIdleMode {
+			trackLimiterEvent = pp.limiterEvent.start(limiterEventIdleMarkWork, startTime)
+		}
+
+		decnwait := atomic.Xadd(&work.nwait, -1)
+		if decnwait == work.nproc {
+			println("runtime: work.nwait=", decnwait, "work.nproc=", work.nproc)
+			throw("work.nwait was > work.nproc")
+		}
+
+		systemstack(func() {
+			// Mark our goroutine preemptible so its stack
+			// can be scanned. This lets two mark workers
+			// scan each other (otherwise, they would
+			// deadlock). We must not modify anything on
+			// the G stack. However, stack shrinking is
+			// disabled for mark workers, so it is safe to
+			// read from the G stack.
+			casgstatus(gp, _Grunning, _Gwaiting)
+			switch pp.gcMarkWorkerMode {
+			default:
+				throw("gcBgMarkWorker: unexpected gcMarkWorkerMode")
+			case gcMarkWorkerDedicatedMode:
+				gcDrain(&pp.gcw, gcDrainUntilPreempt|gcDrainFlushBgCredit)
+				if gp.preempt {
+					// We were preempted. This is
+					// a useful signal to kick
+					// everything out of the run
+					// queue so it can run
+					// somewhere else.
+					if drainQ, n := runqdrain(pp); n > 0 {
+						lock(&sched.lock)
+						globrunqputbatch(&drainQ, int32(n))
+						unlock(&sched.lock)
+					}
+				}
+				// Go back to draining, this time
+				// without preemption.
+				gcDrain(&pp.gcw, gcDrainFlushBgCredit)
+			case gcMarkWorkerFractionalMode:
+				gcDrain(&pp.gcw, gcDrainFractional|gcDrainUntilPreempt|gcDrainFlushBgCredit)
+			case gcMarkWorkerIdleMode:
+				gcDrain(&pp.gcw, gcDrainIdle|gcDrainUntilPreempt|gcDrainFlushBgCredit)
+			}
+			casgstatus(gp, _Gwaiting, _Grunning)
+		})
+
+		// Account for time and mark us as stopped.
+		now := nanotime()
+		duration := now - startTime
+		gcController.markWorkerStop(pp.gcMarkWorkerMode, duration)
+		if trackLimiterEvent {
+			pp.limiterEvent.stop(limiterEventIdleMarkWork, now)
+		}
+		if pp.gcMarkWorkerMode == gcMarkWorkerFractionalMode {
+			atomic.Xaddint64(&pp.gcFractionalMarkTime, duration)
+		}
+
+		// Was this the last worker and did we run out
+		// of work?
+		incnwait := atomic.Xadd(&work.nwait, +1)
+		if incnwait > work.nproc {
+			println("runtime: p.gcMarkWorkerMode=", pp.gcMarkWorkerMode,
+				"work.nwait=", incnwait, "work.nproc=", work.nproc)
+			throw("work.nwait > work.nproc")
+		}
+
+		// We'll releasem after this point and thus this P may run
+		// something else. We must clear the worker mode to avoid
+		// attributing the mode to a different (non-worker) G in
+		// traceGoStart.
+		pp.gcMarkWorkerMode = gcMarkWorkerNotWorker
+
+		// If this worker reached a background mark completion
+		// point, signal the main GC goroutine.
+		if incnwait == work.nproc && !gcMarkWorkAvailable(nil) {
+			// We don't need the P-local buffers here, allow
+			// preemption because we may schedule like a regular
+			// goroutine in gcMarkDone (block on locks, etc).
+			releasem(node.m.ptr())
+			node.m.set(nil)
+
+			gcMarkDone()
+		}
+	}
+}
+
+// gcMarkWorkAvailable reports whether executing a mark worker
+// on p is potentially useful. p may be nil, in which case it only
+// checks the global sources of work.
+func gcMarkWorkAvailable(p *p) bool {
+	if p != nil && !p.gcw.empty() {
+		return true
+	}
+	if !work.full.empty() {
+		return true // global work available
+	}
+	if work.markrootNext < work.markrootJobs {
+		return true // root scan work available
+	}
+	return false
+}
+
+// gcMark runs the mark (or, for concurrent GC, mark termination)
+// All gcWork caches must be empty.
+// STW is in effect at this point.
+func gcMark(startTime int64) {
+	if debug.allocfreetrace > 0 {
+		tracegc()
+	}
+
+	if gcphase != _GCmarktermination {
+		throw("in gcMark expecting to see gcphase as _GCmarktermination")
+	}
+	work.tstart = startTime
+
+	// Check that there's no marking work remaining.
+	if work.full != 0 || work.markrootNext < work.markrootJobs {
+		print("runtime: full=", hex(work.full), " next=", work.markrootNext, " jobs=", work.markrootJobs, " nDataRoots=", work.nDataRoots, " nBSSRoots=", work.nBSSRoots, " nSpanRoots=", work.nSpanRoots, " nStackRoots=", work.nStackRoots, "\n")
+		panic("non-empty mark queue after concurrent mark")
+	}
+
+	if debug.gccheckmark > 0 {
+		// This is expensive when there's a large number of
+		// Gs, so only do it if checkmark is also enabled.
+		gcMarkRootCheck()
+	}
+	if work.full != 0 {
+		throw("work.full != 0")
+	}
+
+	// Drop allg snapshot. allgs may have grown, in which case
+	// this is the only reference to the old backing store and
+	// there's no need to keep it around.
+	work.stackRoots = nil
+
+	// Clear out buffers and double-check that all gcWork caches
+	// are empty. This should be ensured by gcMarkDone before we
+	// enter mark termination.
+	//
+	// TODO: We could clear out buffers just before mark if this
+	// has a non-negligible impact on STW time.
+	for _, p := range allp {
+		// The write barrier may have buffered pointers since
+		// the gcMarkDone barrier. However, since the barrier
+		// ensured all reachable objects were marked, all of
+		// these must be pointers to black objects. Hence we
+		// can just discard the write barrier buffer.
+		if debug.gccheckmark > 0 {
+			// For debugging, flush the buffer and make
+			// sure it really was all marked.
+			wbBufFlush1(p)
+		} else {
+			p.wbBuf.reset()
+		}
+
+		gcw := &p.gcw
+		if !gcw.empty() {
+			printlock()
+			print("runtime: P ", p.id, " flushedWork ", gcw.flushedWork)
+			if gcw.wbuf1 == nil {
+				print(" wbuf1=<nil>")
+			} else {
+				print(" wbuf1.n=", gcw.wbuf1.nobj)
+			}
+			if gcw.wbuf2 == nil {
+				print(" wbuf2=<nil>")
+			} else {
+				print(" wbuf2.n=", gcw.wbuf2.nobj)
+			}
+			print("\n")
+			throw("P has cached GC work at end of mark termination")
+		}
+		// There may still be cached empty buffers, which we
+		// need to flush since we're going to free them. Also,
+		// there may be non-zero stats because we allocated
+		// black after the gcMarkDone barrier.
+		gcw.dispose()
+	}
+
+	// Flush scanAlloc from each mcache since we're about to modify
+	// heapScan directly. If we were to flush this later, then scanAlloc
+	// might have incorrect information.
+	//
+	// Note that it's not important to retain this information; we know
+	// exactly what heapScan is at this point via scanWork.
+	for _, p := range allp {
+		c := p.mcache
+		if c == nil {
+			continue
+		}
+		c.scanAlloc = 0
+	}
+
+	// Reset controller state.
+	gcController.resetLive(work.bytesMarked)
+}
+
+// gcSweep must be called on the system stack because it acquires the heap
+// lock. See mheap for details.
+//
+// The world must be stopped.
+//
+//go:systemstack
+func gcSweep(mode gcMode) {
+	assertWorldStopped()
+
+	if gcphase != _GCoff {
+		throw("gcSweep being done but phase is not GCoff")
+	}
+
+	lock(&mheap_.lock)
+	mheap_.sweepgen += 2
+	sweep.active.reset()
+	mheap_.pagesSwept.Store(0)
+	mheap_.sweepArenas = mheap_.allArenas
+	mheap_.reclaimIndex.Store(0)
+	mheap_.reclaimCredit.Store(0)
+	unlock(&mheap_.lock)
+
+	sweep.centralIndex.clear()
+
+	if !_ConcurrentSweep || mode == gcForceBlockMode {
+		// Special case synchronous sweep.
+		// Record that no proportional sweeping has to happen.
+		lock(&mheap_.lock)
+		mheap_.sweepPagesPerByte = 0
+		unlock(&mheap_.lock)
+		// Sweep all spans eagerly.
+		for sweepone() != ^uintptr(0) {
+			sweep.npausesweep++
+		}
+		// Free workbufs eagerly.
+		prepareFreeWorkbufs()
+		for freeSomeWbufs(false) {
+		}
+		// All "free" events for this mark/sweep cycle have
+		// now happened, so we can make this profile cycle
+		// available immediately.
+		mProf_NextCycle()
+		mProf_Flush()
+		return
+	}
+
+	// Background sweep.
+	lock(&sweep.lock)
+	if sweep.parked {
+		sweep.parked = false
+		ready(sweep.g, 0, true)
+	}
+	unlock(&sweep.lock)
+}
+
+// gcResetMarkState resets global state prior to marking (concurrent
+// or STW) and resets the stack scan state of all Gs.
+//
+// This is safe to do without the world stopped because any Gs created
+// during or after this will start out in the reset state.
+//
+// gcResetMarkState must be called on the system stack because it acquires
+// the heap lock. See mheap for details.
+//
+//go:systemstack
+func gcResetMarkState() {
+	// This may be called during a concurrent phase, so lock to make sure
+	// allgs doesn't change.
+	forEachG(func(gp *g) {
+		gp.gcscandone = false // set to true in gcphasework
+		gp.gcAssistBytes = 0
+	})
+
+	// Clear page marks. This is just 1MB per 64GB of heap, so the
+	// time here is pretty trivial.
+	lock(&mheap_.lock)
+	arenas := mheap_.allArenas
+	unlock(&mheap_.lock)
+	for _, ai := range arenas {
+		ha := mheap_.arenas[ai.l1()][ai.l2()]
+		for i := range ha.pageMarks {
+			ha.pageMarks[i] = 0
+		}
+	}
+
+	work.bytesMarked = 0
+	work.initialHeapLive = atomic.Load64(&gcController.heapLive)
+}
+
+// Hooks for other packages
+
+var poolcleanup func()
+var boringCaches []unsafe.Pointer // for crypto/internal/boring
+
+//go:linkname sync_runtime_registerPoolCleanup sync.runtime_registerPoolCleanup
+func sync_runtime_registerPoolCleanup(f func()) {
+	poolcleanup = f
+}
+
+//go:linkname boring_registerCache crypto/internal/boring/bcache.registerCache
+func boring_registerCache(p unsafe.Pointer) {
+	boringCaches = append(boringCaches, p)
+}
+
+func clearpools() {
+	// clear sync.Pools
+	if poolcleanup != nil {
+		poolcleanup()
+	}
+
+	// clear boringcrypto caches
+	for _, p := range boringCaches {
+		atomicstorep(p, nil)
+	}
+
+	// Clear central sudog cache.
+	// Leave per-P caches alone, they have strictly bounded size.
+	// Disconnect cached list before dropping it on the floor,
+	// so that a dangling ref to one entry does not pin all of them.
+	lock(&sched.sudoglock)
+	var sg, sgnext *sudog
+	for sg = sched.sudogcache; sg != nil; sg = sgnext {
+		sgnext = sg.next
+		sg.next = nil
+	}
+	sched.sudogcache = nil
+	unlock(&sched.sudoglock)
+
+	// Clear central defer pool.
+	// Leave per-P pools alone, they have strictly bounded size.
+	lock(&sched.deferlock)
+	// disconnect cached list before dropping it on the floor,
+	// so that a dangling ref to one entry does not pin all of them.
+	var d, dlink *_defer
+	for d = sched.deferpool; d != nil; d = dlink {
+		dlink = d.link
+		d.link = nil
+	}
+	sched.deferpool = nil
+	unlock(&sched.deferlock)
+}
+
+// Timing
+
+// itoaDiv formats val/(10**dec) into buf.
+func itoaDiv(buf []byte, val uint64, dec int) []byte {
+	i := len(buf) - 1
+	idec := i - dec
+	for val >= 10 || i >= idec {
+		buf[i] = byte(val%10 + '0')
+		i--
+		if i == idec {
+			buf[i] = '.'
+			i--
+		}
+		val /= 10
+	}
+	buf[i] = byte(val + '0')
+	return buf[i:]
+}
+
+// fmtNSAsMS nicely formats ns nanoseconds as milliseconds.
+func fmtNSAsMS(buf []byte, ns uint64) []byte {
+	if ns >= 10e6 {
+		// Format as whole milliseconds.
+		return itoaDiv(buf, ns/1e6, 0)
+	}
+	// Format two digits of precision, with at most three decimal places.
+	x := ns / 1e3
+	if x == 0 {
+		buf[0] = '0'
+		return buf[:1]
+	}
+	dec := 3
+	for x >= 100 {
+		x /= 10
+		dec--
+	}
+	return itoaDiv(buf, x, dec)
+}
+
+// Helpers for testing GC.
+
+// gcTestMoveStackOnNextCall causes the stack to be moved on a call
+// immediately following the call to this. It may not work correctly
+// if any other work appears after this call (such as returning).
+// Typically the following call should be marked go:noinline so it
+// performs a stack check.
+//
+// In rare cases this may not cause the stack to move, specifically if
+// there's a preemption between this call and the next.
+func gcTestMoveStackOnNextCall() {
+	gp := getg()
+	gp.stackguard0 = stackForceMove
+}
+
+// gcTestIsReachable performs a GC and returns a bit set where bit i
+// is set if ptrs[i] is reachable.
+func gcTestIsReachable(ptrs ...unsafe.Pointer) (mask uint64) {
+	// This takes the pointers as unsafe.Pointers in order to keep
+	// them live long enough for us to attach specials. After
+	// that, we drop our references to them.
+
+	if len(ptrs) > 64 {
+		panic("too many pointers for uint64 mask")
+	}
+
+	// Block GC while we attach specials and drop our references
+	// to ptrs. Otherwise, if a GC is in progress, it could mark
+	// them reachable via this function before we have a chance to
+	// drop them.
+	semacquire(&gcsema)
+
+	// Create reachability specials for ptrs.
+	specials := make([]*specialReachable, len(ptrs))
+	for i, p := range ptrs {
+		lock(&mheap_.speciallock)
+		s := (*specialReachable)(mheap_.specialReachableAlloc.alloc())
+		unlock(&mheap_.speciallock)
+		s.special.kind = _KindSpecialReachable
+		if !addspecial(p, &s.special) {
+			throw("already have a reachable special (duplicate pointer?)")
+		}
+		specials[i] = s
+		// Make sure we don't retain ptrs.
+		ptrs[i] = nil
+	}
+
+	semrelease(&gcsema)
+
+	// Force a full GC and sweep.
+	GC()
+
+	// Process specials.
+	for i, s := range specials {
+		if !s.done {
+			printlock()
+			println("runtime: object", i, "was not swept")
+			throw("IsReachable failed")
+		}
+		if s.reachable {
+			mask |= 1 << i
+		}
+		lock(&mheap_.speciallock)
+		mheap_.specialReachableAlloc.free(unsafe.Pointer(s))
+		unlock(&mheap_.speciallock)
+	}
+
+	return mask
+}
+
+// gcTestPointerClass returns the category of what p points to, one of:
+// "heap", "stack", "data", "bss", "other". This is useful for checking
+// that a test is doing what it's intended to do.
+//
+// This is nosplit simply to avoid extra pointer shuffling that may
+// complicate a test.
+//
+//go:nosplit
+func gcTestPointerClass(p unsafe.Pointer) string {
+	p2 := uintptr(noescape(p))
+	gp := getg()
+	if gp.stack.lo <= p2 && p2 < gp.stack.hi {
+		return "stack"
+	}
+	if base, _, _ := findObject(p2, 0, 0); base != 0 {
+		return "heap"
+	}
+	for _, datap := range activeModules() {
+		if datap.data <= p2 && p2 < datap.edata || datap.noptrdata <= p2 && p2 < datap.enoptrdata {
+			return "data"
+		}
+		if datap.bss <= p2 && p2 < datap.ebss || datap.noptrbss <= p2 && p2 <= datap.enoptrbss {
+			return "bss"
+		}
+	}
+	KeepAlive(p)
+	return "other"
+}
diff --git a/contrib/go/_std_1.19/src/runtime/mgclimit.go b/contrib/go/_std_1.19/src/runtime/mgclimit.go
new file mode 100644
index 0000000000..d94e471643
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/mgclimit.go
@@ -0,0 +1,484 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import "runtime/internal/atomic"
+
+// gcCPULimiter is a mechanism to limit GC CPU utilization in situations
+// where it might become excessive and inhibit application progress (e.g.
+// a death spiral).
+//
+// The core of the limiter is a leaky bucket mechanism that fills with GC
+// CPU time and drains with mutator time. Because the bucket fills and
+// drains with time directly (i.e. without any weighting), this effectively
+// sets a very conservative limit of 50%. This limit could be enforced directly,
+// however, but the purpose of the bucket is to accommodate spikes in GC CPU
+// utilization without hurting throughput.
+//
+// Note that the bucket in the leaky bucket mechanism can never go negative,
+// so the GC never gets credit for a lot of CPU time spent without the GC
+// running. This is intentional, as an application that stays idle for, say,
+// an entire day, could build up enough credit to fail to prevent a death
+// spiral the following day. The bucket's capacity is the GC's only leeway.
+//
+// The capacity thus also sets the window the limiter considers. For example,
+// if the capacity of the bucket is 1 cpu-second, then the limiter will not
+// kick in until at least 1 full cpu-second in the last 2 cpu-second window
+// is spent on GC CPU time.
+var gcCPULimiter gcCPULimiterState
+
+type gcCPULimiterState struct {
+	lock atomic.Uint32
+
+	enabled atomic.Bool
+	bucket  struct {
+		// Invariants:
+		// - fill >= 0
+		// - capacity >= 0
+		// - fill <= capacity
+		fill, capacity uint64
+	}
+	// overflow is the cumulative amount of GC CPU time that we tried to fill the
+	// bucket with but exceeded its capacity.
+	overflow uint64
+
+	// gcEnabled is an internal copy of gcBlackenEnabled that determines
+	// whether the limiter tracks total assist time.
+	//
+	// gcBlackenEnabled isn't used directly so as to keep this structure
+	// unit-testable.
+	gcEnabled bool
+
+	// transitioning is true when the GC is in a STW and transitioning between
+	// the mark and sweep phases.
+	transitioning bool
+
+	_ uint32 // Align assistTimePool and lastUpdate on 32-bit platforms.
+
+	// assistTimePool is the accumulated assist time since the last update.
+	assistTimePool atomic.Int64
+
+	// idleMarkTimePool is the accumulated idle mark time since the last update.
+	idleMarkTimePool atomic.Int64
+
+	// idleTimePool is the accumulated time Ps spent on the idle list since the last update.
+	idleTimePool atomic.Int64
+
+	// lastUpdate is the nanotime timestamp of the last time update was called.
+	//
+	// Updated under lock, but may be read concurrently.
+	lastUpdate atomic.Int64
+
+	// lastEnabledCycle is the GC cycle that last had the limiter enabled.
+	lastEnabledCycle atomic.Uint32
+
+	// nprocs is an internal copy of gomaxprocs, used to determine total available
+	// CPU time.
+	//
+	// gomaxprocs isn't used directly so as to keep this structure unit-testable.
+	nprocs int32
+
+	// test indicates whether this instance of the struct was made for testing purposes.
+	test bool
+}
+
+// limiting returns true if the CPU limiter is currently enabled, meaning the Go GC
+// should take action to limit CPU utilization.
+//
+// It is safe to call concurrently with other operations.
+func (l *gcCPULimiterState) limiting() bool {
+	return l.enabled.Load()
+}
+
+// startGCTransition notifies the limiter of a GC transition.
+//
+// This call takes ownership of the limiter and disables all other means of
+// updating the limiter. Release ownership by calling finishGCTransition.
+//
+// It is safe to call concurrently with other operations.
+func (l *gcCPULimiterState) startGCTransition(enableGC bool, now int64) {
+	if !l.tryLock() {
+		// This must happen during a STW, so we can't fail to acquire the lock.
+		// If we did, something went wrong. Throw.
+		throw("failed to acquire lock to start a GC transition")
+	}
+	if l.gcEnabled == enableGC {
+		throw("transitioning GC to the same state as before?")
+	}
+	// Flush whatever was left between the last update and now.
+	l.updateLocked(now)
+	l.gcEnabled = enableGC
+	l.transitioning = true
+	// N.B. finishGCTransition releases the lock.
+	//
+	// We don't release here to increase the chance that if there's a failure
+	// to finish the transition, that we throw on failing to acquire the lock.
+}
+
+// finishGCTransition notifies the limiter that the GC transition is complete
+// and releases ownership of it. It also accumulates STW time in the bucket.
+// now must be the timestamp from the end of the STW pause.
+func (l *gcCPULimiterState) finishGCTransition(now int64) {
+	if !l.transitioning {
+		throw("finishGCTransition called without starting one?")
+	}
+	// Count the full nprocs set of CPU time because the world is stopped
+	// between startGCTransition and finishGCTransition. Even though the GC
+	// isn't running on all CPUs, it is preventing user code from doing so,
+	// so it might as well be.
+	if lastUpdate := l.lastUpdate.Load(); now >= lastUpdate {
+		l.accumulate(0, (now-lastUpdate)*int64(l.nprocs))
+	}
+	l.lastUpdate.Store(now)
+	l.transitioning = false
+	l.unlock()
+}
+
+// gcCPULimiterUpdatePeriod dictates the maximum amount of wall-clock time
+// we can go before updating the limiter.
+const gcCPULimiterUpdatePeriod = 10e6 // 10ms
+
+// needUpdate returns true if the limiter's maximum update period has been
+// exceeded, and so would benefit from an update.
+func (l *gcCPULimiterState) needUpdate(now int64) bool {
+	return now-l.lastUpdate.Load() > gcCPULimiterUpdatePeriod
+}
+
+// addAssistTime notifies the limiter of additional assist time. It will be
+// included in the next update.
+func (l *gcCPULimiterState) addAssistTime(t int64) {
+	l.assistTimePool.Add(t)
+}
+
+// addIdleTime notifies the limiter of additional time a P spent on the idle list. It will be
+// subtracted from the total CPU time in the next update.
+func (l *gcCPULimiterState) addIdleTime(t int64) {
+	l.idleTimePool.Add(t)
+}
+
+// update updates the bucket given runtime-specific information. now is the
+// current monotonic time in nanoseconds.
+//
+// This is safe to call concurrently with other operations, except *GCTransition.
+func (l *gcCPULimiterState) update(now int64) {
+	if !l.tryLock() {
+		// We failed to acquire the lock, which means something else is currently
+		// updating. Just drop our update, the next one to update will include
+		// our total assist time.
+		return
+	}
+	if l.transitioning {
+		throw("update during transition")
+	}
+	l.updateLocked(now)
+	l.unlock()
+}
+
+// updatedLocked is the implementation of update. l.lock must be held.
+func (l *gcCPULimiterState) updateLocked(now int64) {
+	lastUpdate := l.lastUpdate.Load()
+	if now < lastUpdate {
+		// Defensively avoid overflow. This isn't even the latest update anyway.
+		return
+	}
+	windowTotalTime := (now - lastUpdate) * int64(l.nprocs)
+	l.lastUpdate.Store(now)
+
+	// Drain the pool of assist time.
+	assistTime := l.assistTimePool.Load()
+	if assistTime != 0 {
+		l.assistTimePool.Add(-assistTime)
+	}
+
+	// Drain the pool of idle time.
+	idleTime := l.idleTimePool.Load()
+	if idleTime != 0 {
+		l.idleTimePool.Add(-idleTime)
+	}
+
+	if !l.test {
+		// Consume time from in-flight events. Make sure we're not preemptible so allp can't change.
+		//
+		// The reason we do this instead of just waiting for those events to finish and push updates
+		// is to ensure that all the time we're accounting for happened sometime between lastUpdate
+		// and now. This dramatically simplifies reasoning about the limiter because we're not at
+		// risk of extra time being accounted for in this window than actually happened in this window,
+		// leading to all sorts of weird transient behavior.
+		mp := acquirem()
+		for _, pp := range allp {
+			typ, duration := pp.limiterEvent.consume(now)
+			switch typ {
+			case limiterEventIdleMarkWork:
+				fallthrough
+			case limiterEventIdle:
+				idleTime += duration
+			case limiterEventMarkAssist:
+				fallthrough
+			case limiterEventScavengeAssist:
+				assistTime += duration
+			case limiterEventNone:
+				break
+			default:
+				throw("invalid limiter event type found")
+			}
+		}
+		releasem(mp)
+	}
+
+	// Compute total GC time.
+	windowGCTime := assistTime
+	if l.gcEnabled {
+		windowGCTime += int64(float64(windowTotalTime) * gcBackgroundUtilization)
+	}
+
+	// Subtract out all idle time from the total time. Do this after computing
+	// GC time, because the background utilization is dependent on the *real*
+	// total time, not the total time after idle time is subtracted.
+	//
+	// Idle time is counted as any time that a P is on the P idle list plus idle mark
+	// time. Idle mark workers soak up time that the application spends idle.
+	//
+	// On a heavily undersubscribed system, any additional idle time can skew GC CPU
+	// utilization, because the GC might be executing continuously and thrashing,
+	// yet the CPU utilization with respect to GOMAXPROCS will be quite low, so
+	// the limiter fails to turn on. By subtracting idle time, we're removing time that
+	// we know the application was idle giving a more accurate picture of whether
+	// the GC is thrashing.
+	//
+	// Note that this can cause the limiter to turn on even if it's not needed. For
+	// instance, on a system with 32 Ps but only 1 running goroutine, each GC will have
+	// 8 dedicated GC workers. Assuming the GC cycle is half mark phase and half sweep
+	// phase, then the GC CPU utilization over that cycle, with idle time removed, will
+	// be 8/(8+2) = 80%. Even though the limiter turns on, though, assist should be
+	// unnecessary, as the GC has way more CPU time to outpace the 1 goroutine that's
+	// running.
+	windowTotalTime -= idleTime
+
+	l.accumulate(windowTotalTime-windowGCTime, windowGCTime)
+}
+
+// accumulate adds time to the bucket and signals whether the limiter is enabled.
+//
+// This is an internal function that deals just with the bucket. Prefer update.
+// l.lock must be held.
+func (l *gcCPULimiterState) accumulate(mutatorTime, gcTime int64) {
+	headroom := l.bucket.capacity - l.bucket.fill
+	enabled := headroom == 0
+
+	// Let's be careful about three things here:
+	// 1. The addition and subtraction, for the invariants.
+	// 2. Overflow.
+	// 3. Excessive mutation of l.enabled, which is accessed
+	//    by all assists, potentially more than once.
+	change := gcTime - mutatorTime
+
+	// Handle limiting case.
+	if change > 0 && headroom <= uint64(change) {
+		l.overflow += uint64(change) - headroom
+		l.bucket.fill = l.bucket.capacity
+		if !enabled {
+			l.enabled.Store(true)
+			l.lastEnabledCycle.Store(memstats.numgc + 1)
+		}
+		return
+	}
+
+	// Handle non-limiting cases.
+	if change < 0 && l.bucket.fill <= uint64(-change) {
+		// Bucket emptied.
+		l.bucket.fill = 0
+	} else {
+		// All other cases.
+		l.bucket.fill -= uint64(-change)
+	}
+	if change != 0 && enabled {
+		l.enabled.Store(false)
+	}
+}
+
+// tryLock attempts to lock l. Returns true on success.
+func (l *gcCPULimiterState) tryLock() bool {
+	return l.lock.CompareAndSwap(0, 1)
+}
+
+// unlock releases the lock on l. Must be called if tryLock returns true.
+func (l *gcCPULimiterState) unlock() {
+	old := l.lock.Swap(0)
+	if old != 1 {
+		throw("double unlock")
+	}
+}
+
+// capacityPerProc is the limiter's bucket capacity for each P in GOMAXPROCS.
+const capacityPerProc = 1e9 // 1 second in nanoseconds
+
+// resetCapacity updates the capacity based on GOMAXPROCS. Must not be called
+// while the GC is enabled.
+//
+// It is safe to call concurrently with other operations.
+func (l *gcCPULimiterState) resetCapacity(now int64, nprocs int32) {
+	if !l.tryLock() {
+		// This must happen during a STW, so we can't fail to acquire the lock.
+		// If we did, something went wrong. Throw.
+		throw("failed to acquire lock to reset capacity")
+	}
+	// Flush the rest of the time for this period.
+	l.updateLocked(now)
+	l.nprocs = nprocs
+
+	l.bucket.capacity = uint64(nprocs) * capacityPerProc
+	if l.bucket.fill > l.bucket.capacity {
+		l.bucket.fill = l.bucket.capacity
+		l.enabled.Store(true)
+		l.lastEnabledCycle.Store(memstats.numgc + 1)
+	} else if l.bucket.fill < l.bucket.capacity {
+		l.enabled.Store(false)
+	}
+	l.unlock()
+}
+
+// limiterEventType indicates the type of an event occuring on some P.
+//
+// These events represent the full set of events that the GC CPU limiter tracks
+// to execute its function.
+//
+// This type may use no more than limiterEventBits bits of information.
+type limiterEventType uint8
+
+const (
+	limiterEventNone           limiterEventType = iota // None of the following events.
+	limiterEventIdleMarkWork                           // Refers to an idle mark worker (see gcMarkWorkerMode).
+	limiterEventMarkAssist                             // Refers to mark assist (see gcAssistAlloc).
+	limiterEventScavengeAssist                         // Refers to a scavenge assist (see allocSpan).
+	limiterEventIdle                                   // Refers to time a P spent on the idle list.
+
+	limiterEventBits = 3
+)
+
+// limiterEventTypeMask is a mask for the bits in p.limiterEventStart that represent
+// the event type. The rest of the bits of that field represent a timestamp.
+const (
+	limiterEventTypeMask  = uint64((1<<limiterEventBits)-1) << (64 - limiterEventBits)
+	limiterEventStampNone = limiterEventStamp(0)
+)
+
+// limiterEventStamp is a nanotime timestamp packed with a limiterEventType.
+type limiterEventStamp uint64
+
+// makeLimiterEventStamp creates a new stamp from the event type and the current timestamp.
+func makeLimiterEventStamp(typ limiterEventType, now int64) limiterEventStamp {
+	return limiterEventStamp(uint64(typ)<<(64-limiterEventBits) | (uint64(now) &^ limiterEventTypeMask))
+}
+
+// duration computes the difference between now and the start time stored in the stamp.
+//
+// Returns 0 if the difference is negative, which may happen if now is stale or if the
+// before and after timestamps cross a 2^(64-limiterEventBits) boundary.
+func (s limiterEventStamp) duration(now int64) int64 {
+	// The top limiterEventBits bits of the timestamp are derived from the current time
+	// when computing a duration.
+	start := int64((uint64(now) & limiterEventTypeMask) | (uint64(s) &^ limiterEventTypeMask))
+	if now < start {
+		return 0
+	}
+	return now - start
+}
+
+// type extracts the event type from the stamp.
+func (s limiterEventStamp) typ() limiterEventType {
+	return limiterEventType(s >> (64 - limiterEventBits))
+}
+
+// limiterEvent represents tracking state for an event tracked by the GC CPU limiter.
+type limiterEvent struct {
+	stamp atomic.Uint64 // Stores a limiterEventStamp.
+}
+
+// start begins tracking a new limiter event of the current type. If an event
+// is already in flight, then a new event cannot begin because the current time is
+// already being attributed to that event. In this case, this function returns false.
+// Otherwise, it returns true.
+//
+// The caller must be non-preemptible until at least stop is called or this function
+// returns false. Because this is trying to measure "on-CPU" time of some event, getting
+// scheduled away during it can mean that whatever we're measuring isn't a reflection
+// of "on-CPU" time. The OS could deschedule us at any time, but we want to maintain as
+// close of an approximation as we can.
+func (e *limiterEvent) start(typ limiterEventType, now int64) bool {
+	if limiterEventStamp(e.stamp.Load()).typ() != limiterEventNone {
+		return false
+	}
+	e.stamp.Store(uint64(makeLimiterEventStamp(typ, now)))
+	return true
+}
+
+// consume acquires the partial event CPU time from any in-flight event.
+// It achieves this by storing the current time as the new event time.
+//
+// Returns the type of the in-flight event, as well as how long it's currently been
+// executing for. Returns limiterEventNone if no event is active.
+func (e *limiterEvent) consume(now int64) (typ limiterEventType, duration int64) {
+	// Read the limiter event timestamp and update it to now.
+	for {
+		old := limiterEventStamp(e.stamp.Load())
+		typ = old.typ()
+		if typ == limiterEventNone {
+			// There's no in-flight event, so just push that up.
+			return
+		}
+		duration = old.duration(now)
+		if duration == 0 {
+			// We might have a stale now value, or this crossed the
+			// 2^(64-limiterEventBits) boundary in the clock readings.
+			// Just ignore it.
+			return limiterEventNone, 0
+		}
+		new := makeLimiterEventStamp(typ, now)
+		if e.stamp.CompareAndSwap(uint64(old), uint64(new)) {
+			break
+		}
+	}
+	return
+}
+
+// stop stops the active limiter event. Throws if the
+//
+// The caller must be non-preemptible across the event. See start as to why.
+func (e *limiterEvent) stop(typ limiterEventType, now int64) {
+	var stamp limiterEventStamp
+	for {
+		stamp = limiterEventStamp(e.stamp.Load())
+		if stamp.typ() != typ {
+			print("runtime: want=", typ, " got=", stamp.typ(), "\n")
+			throw("limiterEvent.stop: found wrong event in p's limiter event slot")
+		}
+		if e.stamp.CompareAndSwap(uint64(stamp), uint64(limiterEventStampNone)) {
+			break
+		}
+	}
+	duration := stamp.duration(now)
+	if duration == 0 {
+		// It's possible that we're missing time because we crossed a
+		// 2^(64-limiterEventBits) boundary between the start and end.
+		// In this case, we're dropping that information. This is OK because
+		// at worst it'll cause a transient hiccup that will quickly resolve
+		// itself as all new timestamps begin on the other side of the boundary.
+		// Such a hiccup should be incredibly rare.
+		return
+	}
+	// Account for the event.
+	switch typ {
+	case limiterEventIdleMarkWork:
+		fallthrough
+	case limiterEventIdle:
+		gcCPULimiter.addIdleTime(duration)
+	case limiterEventMarkAssist:
+		fallthrough
+	case limiterEventScavengeAssist:
+		gcCPULimiter.addAssistTime(duration)
+	default:
+		throw("limiterEvent.stop: invalid limiter event type found")
+	}
+}
diff --git a/contrib/go/_std_1.19/src/runtime/mgcmark.go b/contrib/go/_std_1.19/src/runtime/mgcmark.go
new file mode 100644
index 0000000000..74637072c5
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/mgcmark.go
@@ -0,0 +1,1601 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Garbage collector: marking and scanning
+
+package runtime
+
+import (
+	"internal/goarch"
+	"runtime/internal/atomic"
+	"runtime/internal/sys"
+	"unsafe"
+)
+
+const (
+	fixedRootFinalizers = iota
+	fixedRootFreeGStacks
+	fixedRootCount
+
+	// rootBlockBytes is the number of bytes to scan per data or
+	// BSS root.
+	rootBlockBytes = 256 << 10
+
+	// maxObletBytes is the maximum bytes of an object to scan at
+	// once. Larger objects will be split up into "oblets" of at
+	// most this size. Since we can scan 1–2 MB/ms, 128 KB bounds
+	// scan preemption at ~100 µs.
+	//
+	// This must be > _MaxSmallSize so that the object base is the
+	// span base.
+	maxObletBytes = 128 << 10
+
+	// drainCheckThreshold specifies how many units of work to do
+	// between self-preemption checks in gcDrain. Assuming a scan
+	// rate of 1 MB/ms, this is ~100 µs. Lower values have higher
+	// overhead in the scan loop (the scheduler check may perform
+	// a syscall, so its overhead is nontrivial). Higher values
+	// make the system less responsive to incoming work.
+	drainCheckThreshold = 100000
+
+	// pagesPerSpanRoot indicates how many pages to scan from a span root
+	// at a time. Used by special root marking.
+	//
+	// Higher values improve throughput by increasing locality, but
+	// increase the minimum latency of a marking operation.
+	//
+	// Must be a multiple of the pageInUse bitmap element size and
+	// must also evenly divide pagesPerArena.
+	pagesPerSpanRoot = 512
+)
+
+// gcMarkRootPrepare queues root scanning jobs (stacks, globals, and
+// some miscellany) and initializes scanning-related state.
+//
+// The world must be stopped.
+func gcMarkRootPrepare() {
+	assertWorldStopped()
+
+	// Compute how many data and BSS root blocks there are.
+	nBlocks := func(bytes uintptr) int {
+		return int(divRoundUp(bytes, rootBlockBytes))
+	}
+
+	work.nDataRoots = 0
+	work.nBSSRoots = 0
+
+	// Scan globals.
+	for _, datap := range activeModules() {
+		nDataRoots := nBlocks(datap.edata - datap.data)
+		if nDataRoots > work.nDataRoots {
+			work.nDataRoots = nDataRoots
+		}
+	}
+
+	for _, datap := range activeModules() {
+		nBSSRoots := nBlocks(datap.ebss - datap.bss)
+		if nBSSRoots > work.nBSSRoots {
+			work.nBSSRoots = nBSSRoots
+		}
+	}
+
+	// Scan span roots for finalizer specials.
+	//
+	// We depend on addfinalizer to mark objects that get
+	// finalizers after root marking.
+	//
+	// We're going to scan the whole heap (that was available at the time the
+	// mark phase started, i.e. markArenas) for in-use spans which have specials.
+	//
+	// Break up the work into arenas, and further into chunks.
+	//
+	// Snapshot allArenas as markArenas. This snapshot is safe because allArenas
+	// is append-only.
+	mheap_.markArenas = mheap_.allArenas[:len(mheap_.allArenas):len(mheap_.allArenas)]
+	work.nSpanRoots = len(mheap_.markArenas) * (pagesPerArena / pagesPerSpanRoot)
+
+	// Scan stacks.
+	//
+	// Gs may be created after this point, but it's okay that we
+	// ignore them because they begin life without any roots, so
+	// there's nothing to scan, and any roots they create during
+	// the concurrent phase will be caught by the write barrier.
+	work.stackRoots = allGsSnapshot()
+	work.nStackRoots = len(work.stackRoots)
+
+	work.markrootNext = 0
+	work.markrootJobs = uint32(fixedRootCount + work.nDataRoots + work.nBSSRoots + work.nSpanRoots + work.nStackRoots)
+
+	// Calculate base indexes of each root type
+	work.baseData = uint32(fixedRootCount)
+	work.baseBSS = work.baseData + uint32(work.nDataRoots)
+	work.baseSpans = work.baseBSS + uint32(work.nBSSRoots)
+	work.baseStacks = work.baseSpans + uint32(work.nSpanRoots)
+	work.baseEnd = work.baseStacks + uint32(work.nStackRoots)
+}
+
+// gcMarkRootCheck checks that all roots have been scanned. It is
+// purely for debugging.
+func gcMarkRootCheck() {
+	if work.markrootNext < work.markrootJobs {
+		print(work.markrootNext, " of ", work.markrootJobs, " markroot jobs done\n")
+		throw("left over markroot jobs")
+	}
+
+	// Check that stacks have been scanned.
+	//
+	// We only check the first nStackRoots Gs that we should have scanned.
+	// Since we don't care about newer Gs (see comment in
+	// gcMarkRootPrepare), no locking is required.
+	i := 0
+	forEachGRace(func(gp *g) {
+		if i >= work.nStackRoots {
+			return
+		}
+
+		if !gp.gcscandone {
+			println("gp", gp, "goid", gp.goid,
+				"status", readgstatus(gp),
+				"gcscandone", gp.gcscandone)
+			throw("scan missed a g")
+		}
+
+		i++
+	})
+}
+
+// ptrmask for an allocation containing a single pointer.
+var oneptrmask = [...]uint8{1}
+
+// markroot scans the i'th root.
+//
+// Preemption must be disabled (because this uses a gcWork).
+//
+// Returns the amount of GC work credit produced by the operation.
+// If flushBgCredit is true, then that credit is also flushed
+// to the background credit pool.
+//
+// nowritebarrier is only advisory here.
+//
+//go:nowritebarrier
+func markroot(gcw *gcWork, i uint32, flushBgCredit bool) int64 {
+	// Note: if you add a case here, please also update heapdump.go:dumproots.
+	var workDone int64
+	var workCounter *atomic.Int64
+	switch {
+	case work.baseData <= i && i < work.baseBSS:
+		workCounter = &gcController.globalsScanWork
+		for _, datap := range activeModules() {
+			workDone += markrootBlock(datap.data, datap.edata-datap.data, datap.gcdatamask.bytedata, gcw, int(i-work.baseData))
+		}
+
+	case work.baseBSS <= i && i < work.baseSpans:
+		workCounter = &gcController.globalsScanWork
+		for _, datap := range activeModules() {
+			workDone += markrootBlock(datap.bss, datap.ebss-datap.bss, datap.gcbssmask.bytedata, gcw, int(i-work.baseBSS))
+		}
+
+	case i == fixedRootFinalizers:
+		for fb := allfin; fb != nil; fb = fb.alllink {
+			cnt := uintptr(atomic.Load(&fb.cnt))
+			scanblock(uintptr(unsafe.Pointer(&fb.fin[0])), cnt*unsafe.Sizeof(fb.fin[0]), &finptrmask[0], gcw, nil)
+		}
+
+	case i == fixedRootFreeGStacks:
+		// Switch to the system stack so we can call
+		// stackfree.
+		systemstack(markrootFreeGStacks)
+
+	case work.baseSpans <= i && i < work.baseStacks:
+		// mark mspan.specials
+		markrootSpans(gcw, int(i-work.baseSpans))
+
+	default:
+		// the rest is scanning goroutine stacks
+		workCounter = &gcController.stackScanWork
+		if i < work.baseStacks || work.baseEnd <= i {
+			printlock()
+			print("runtime: markroot index ", i, " not in stack roots range [", work.baseStacks, ", ", work.baseEnd, ")\n")
+			throw("markroot: bad index")
+		}
+		gp := work.stackRoots[i-work.baseStacks]
+
+		// remember when we've first observed the G blocked
+		// needed only to output in traceback
+		status := readgstatus(gp) // We are not in a scan state
+		if (status == _Gwaiting || status == _Gsyscall) && gp.waitsince == 0 {
+			gp.waitsince = work.tstart
+		}
+
+		// scanstack must be done on the system stack in case
+		// we're trying to scan our own stack.
+		systemstack(func() {
+			// If this is a self-scan, put the user G in
+			// _Gwaiting to prevent self-deadlock. It may
+			// already be in _Gwaiting if this is a mark
+			// worker or we're in mark termination.
+			userG := getg().m.curg
+			selfScan := gp == userG && readgstatus(userG) == _Grunning
+			if selfScan {
+				casgstatus(userG, _Grunning, _Gwaiting)
+				userG.waitreason = waitReasonGarbageCollectionScan
+			}
+
+			// TODO: suspendG blocks (and spins) until gp
+			// stops, which may take a while for
+			// running goroutines. Consider doing this in
+			// two phases where the first is non-blocking:
+			// we scan the stacks we can and ask running
+			// goroutines to scan themselves; and the
+			// second blocks.
+			stopped := suspendG(gp)
+			if stopped.dead {
+				gp.gcscandone = true
+				return
+			}
+			if gp.gcscandone {
+				throw("g already scanned")
+			}
+			workDone += scanstack(gp, gcw)
+			gp.gcscandone = true
+			resumeG(stopped)
+
+			if selfScan {
+				casgstatus(userG, _Gwaiting, _Grunning)
+			}
+		})
+	}
+	if workCounter != nil && workDone != 0 {
+		workCounter.Add(workDone)
+		if flushBgCredit {
+			gcFlushBgCredit(workDone)
+		}
+	}
+	return workDone
+}
+
+// markrootBlock scans the shard'th shard of the block of memory [b0,
+// b0+n0), with the given pointer mask.
+//
+// Returns the amount of work done.
+//
+//go:nowritebarrier
+func markrootBlock(b0, n0 uintptr, ptrmask0 *uint8, gcw *gcWork, shard int) int64 {
+	if rootBlockBytes%(8*goarch.PtrSize) != 0 {
+		// This is necessary to pick byte offsets in ptrmask0.
+		throw("rootBlockBytes must be a multiple of 8*ptrSize")
+	}
+
+	// Note that if b0 is toward the end of the address space,
+	// then b0 + rootBlockBytes might wrap around.
+	// These tests are written to avoid any possible overflow.
+	off := uintptr(shard) * rootBlockBytes
+	if off >= n0 {
+		return 0
+	}
+	b := b0 + off
+	ptrmask := (*uint8)(add(unsafe.Pointer(ptrmask0), uintptr(shard)*(rootBlockBytes/(8*goarch.PtrSize))))
+	n := uintptr(rootBlockBytes)
+	if off+n > n0 {
+		n = n0 - off
+	}
+
+	// Scan this shard.
+	scanblock(b, n, ptrmask, gcw, nil)
+	return int64(n)
+}
+
+// markrootFreeGStacks frees stacks of dead Gs.
+//
+// This does not free stacks of dead Gs cached on Ps, but having a few
+// cached stacks around isn't a problem.
+func markrootFreeGStacks() {
+	// Take list of dead Gs with stacks.
+	lock(&sched.gFree.lock)
+	list := sched.gFree.stack
+	sched.gFree.stack = gList{}
+	unlock(&sched.gFree.lock)
+	if list.empty() {
+		return
+	}
+
+	// Free stacks.
+	q := gQueue{list.head, list.head}
+	for gp := list.head.ptr(); gp != nil; gp = gp.schedlink.ptr() {
+		stackfree(gp.stack)
+		gp.stack.lo = 0
+		gp.stack.hi = 0
+		// Manipulate the queue directly since the Gs are
+		// already all linked the right way.
+		q.tail.set(gp)
+	}
+
+	// Put Gs back on the free list.
+	lock(&sched.gFree.lock)
+	sched.gFree.noStack.pushAll(q)
+	unlock(&sched.gFree.lock)
+}
+
+// markrootSpans marks roots for one shard of markArenas.
+//
+//go:nowritebarrier
+func markrootSpans(gcw *gcWork, shard int) {
+	// Objects with finalizers have two GC-related invariants:
+	//
+	// 1) Everything reachable from the object must be marked.
+	// This ensures that when we pass the object to its finalizer,
+	// everything the finalizer can reach will be retained.
+	//
+	// 2) Finalizer specials (which are not in the garbage
+	// collected heap) are roots. In practice, this means the fn
+	// field must be scanned.
+	sg := mheap_.sweepgen
+
+	// Find the arena and page index into that arena for this shard.
+	ai := mheap_.markArenas[shard/(pagesPerArena/pagesPerSpanRoot)]
+	ha := mheap_.arenas[ai.l1()][ai.l2()]
+	arenaPage := uint(uintptr(shard) * pagesPerSpanRoot % pagesPerArena)
+
+	// Construct slice of bitmap which we'll iterate over.
+	specialsbits := ha.pageSpecials[arenaPage/8:]
+	specialsbits = specialsbits[:pagesPerSpanRoot/8]
+	for i := range specialsbits {
+		// Find set bits, which correspond to spans with specials.
+		specials := atomic.Load8(&specialsbits[i])
+		if specials == 0 {
+			continue
+		}
+		for j := uint(0); j < 8; j++ {
+			if specials&(1<<j) == 0 {
+				continue
+			}
+			// Find the span for this bit.
+			//
+			// This value is guaranteed to be non-nil because having
+			// specials implies that the span is in-use, and since we're
+			// currently marking we can be sure that we don't have to worry
+			// about the span being freed and re-used.
+			s := ha.spans[arenaPage+uint(i)*8+j]
+
+			// The state must be mSpanInUse if the specials bit is set, so
+			// sanity check that.
+			if state := s.state.get(); state != mSpanInUse {
+				print("s.state = ", state, "\n")
+				throw("non in-use span found with specials bit set")
+			}
+			// Check that this span was swept (it may be cached or uncached).
+			if !useCheckmark && !(s.sweepgen == sg || s.sweepgen == sg+3) {
+				// sweepgen was updated (+2) during non-checkmark GC pass
+				print("sweep ", s.sweepgen, " ", sg, "\n")
+				throw("gc: unswept span")
+			}
+
+			// Lock the specials to prevent a special from being
+			// removed from the list while we're traversing it.
+			lock(&s.speciallock)
+			for sp := s.specials; sp != nil; sp = sp.next {
+				if sp.kind != _KindSpecialFinalizer {
+					continue
+				}
+				// don't mark finalized object, but scan it so we
+				// retain everything it points to.
+				spf := (*specialfinalizer)(unsafe.Pointer(sp))
+				// A finalizer can be set for an inner byte of an object, find object beginning.
+				p := s.base() + uintptr(spf.special.offset)/s.elemsize*s.elemsize
+
+				// Mark everything that can be reached from
+				// the object (but *not* the object itself or
+				// we'll never collect it).
+				scanobject(p, gcw)
+
+				// The special itself is a root.
+				scanblock(uintptr(unsafe.Pointer(&spf.fn)), goarch.PtrSize, &oneptrmask[0], gcw, nil)
+			}
+			unlock(&s.speciallock)
+		}
+	}
+}
+
+// gcAssistAlloc performs GC work to make gp's assist debt positive.
+// gp must be the calling user goroutine.
+//
+// This must be called with preemption enabled.
+func gcAssistAlloc(gp *g) {
+	// Don't assist in non-preemptible contexts. These are
+	// generally fragile and won't allow the assist to block.
+	if getg() == gp.m.g0 {
+		return
+	}
+	if mp := getg().m; mp.locks > 0 || mp.preemptoff != "" {
+		return
+	}
+
+	traced := false
+retry:
+	if go119MemoryLimitSupport && gcCPULimiter.limiting() {
+		// If the CPU limiter is enabled, intentionally don't
+		// assist to reduce the amount of CPU time spent in the GC.
+		if traced {
+			traceGCMarkAssistDone()
+		}
+		return
+	}
+	// Compute the amount of scan work we need to do to make the
+	// balance positive. When the required amount of work is low,
+	// we over-assist to build up credit for future allocations
+	// and amortize the cost of assisting.
+	assistWorkPerByte := gcController.assistWorkPerByte.Load()
+	assistBytesPerWork := gcController.assistBytesPerWork.Load()
+	debtBytes := -gp.gcAssistBytes
+	scanWork := int64(assistWorkPerByte * float64(debtBytes))
+	if scanWork < gcOverAssistWork {
+		scanWork = gcOverAssistWork
+		debtBytes = int64(assistBytesPerWork * float64(scanWork))
+	}
+
+	// Steal as much credit as we can from the background GC's
+	// scan credit. This is racy and may drop the background
+	// credit below 0 if two mutators steal at the same time. This
+	// will just cause steals to fail until credit is accumulated
+	// again, so in the long run it doesn't really matter, but we
+	// do have to handle the negative credit case.
+	bgScanCredit := atomic.Loadint64(&gcController.bgScanCredit)
+	stolen := int64(0)
+	if bgScanCredit > 0 {
+		if bgScanCredit < scanWork {
+			stolen = bgScanCredit
+			gp.gcAssistBytes += 1 + int64(assistBytesPerWork*float64(stolen))
+		} else {
+			stolen = scanWork
+			gp.gcAssistBytes += debtBytes
+		}
+		atomic.Xaddint64(&gcController.bgScanCredit, -stolen)
+
+		scanWork -= stolen
+
+		if scanWork == 0 {
+			// We were able to steal all of the credit we
+			// needed.
+			if traced {
+				traceGCMarkAssistDone()
+			}
+			return
+		}
+	}
+
+	if trace.enabled && !traced {
+		traced = true
+		traceGCMarkAssistStart()
+	}
+
+	// Perform assist work
+	systemstack(func() {
+		gcAssistAlloc1(gp, scanWork)
+		// The user stack may have moved, so this can't touch
+		// anything on it until it returns from systemstack.
+	})
+
+	completed := gp.param != nil
+	gp.param = nil
+	if completed {
+		gcMarkDone()
+	}
+
+	if gp.gcAssistBytes < 0 {
+		// We were unable steal enough credit or perform
+		// enough work to pay off the assist debt. We need to
+		// do one of these before letting the mutator allocate
+		// more to prevent over-allocation.
+		//
+		// If this is because we were preempted, reschedule
+		// and try some more.
+		if gp.preempt {
+			Gosched()
+			goto retry
+		}
+
+		// Add this G to an assist queue and park. When the GC
+		// has more background credit, it will satisfy queued
+		// assists before flushing to the global credit pool.
+		//
+		// Note that this does *not* get woken up when more
+		// work is added to the work list. The theory is that
+		// there wasn't enough work to do anyway, so we might
+		// as well let background marking take care of the
+		// work that is available.
+		if !gcParkAssist() {
+			goto retry
+		}
+
+		// At this point either background GC has satisfied
+		// this G's assist debt, or the GC cycle is over.
+	}
+	if traced {
+		traceGCMarkAssistDone()
+	}
+}
+
+// gcAssistAlloc1 is the part of gcAssistAlloc that runs on the system
+// stack. This is a separate function to make it easier to see that
+// we're not capturing anything from the user stack, since the user
+// stack may move while we're in this function.
+//
+// gcAssistAlloc1 indicates whether this assist completed the mark
+// phase by setting gp.param to non-nil. This can't be communicated on
+// the stack since it may move.
+//
+//go:systemstack
+func gcAssistAlloc1(gp *g, scanWork int64) {
+	// Clear the flag indicating that this assist completed the
+	// mark phase.
+	gp.param = nil
+
+	if atomic.Load(&gcBlackenEnabled) == 0 {
+		// The gcBlackenEnabled check in malloc races with the
+		// store that clears it but an atomic check in every malloc
+		// would be a performance hit.
+		// Instead we recheck it here on the non-preemptable system
+		// stack to determine if we should perform an assist.
+
+		// GC is done, so ignore any remaining debt.
+		gp.gcAssistBytes = 0
+		return
+	}
+	// Track time spent in this assist. Since we're on the
+	// system stack, this is non-preemptible, so we can
+	// just measure start and end time.
+	//
+	// Limiter event tracking might be disabled if we end up here
+	// while on a mark worker.
+	startTime := nanotime()
+	trackLimiterEvent := gp.m.p.ptr().limiterEvent.start(limiterEventMarkAssist, startTime)
+
+	decnwait := atomic.Xadd(&work.nwait, -1)
+	if decnwait == work.nproc {
+		println("runtime: work.nwait =", decnwait, "work.nproc=", work.nproc)
+		throw("nwait > work.nprocs")
+	}
+
+	// gcDrainN requires the caller to be preemptible.
+	casgstatus(gp, _Grunning, _Gwaiting)
+	gp.waitreason = waitReasonGCAssistMarking
+
+	// drain own cached work first in the hopes that it
+	// will be more cache friendly.
+	gcw := &getg().m.p.ptr().gcw
+	workDone := gcDrainN(gcw, scanWork)
+
+	casgstatus(gp, _Gwaiting, _Grunning)
+
+	// Record that we did this much scan work.
+	//
+	// Back out the number of bytes of assist credit that
+	// this scan work counts for. The "1+" is a poor man's
+	// round-up, to ensure this adds credit even if
+	// assistBytesPerWork is very low.
+	assistBytesPerWork := gcController.assistBytesPerWork.Load()
+	gp.gcAssistBytes += 1 + int64(assistBytesPerWork*float64(workDone))
+
+	// If this is the last worker and we ran out of work,
+	// signal a completion point.
+	incnwait := atomic.Xadd(&work.nwait, +1)
+	if incnwait > work.nproc {
+		println("runtime: work.nwait=", incnwait,
+			"work.nproc=", work.nproc)
+		throw("work.nwait > work.nproc")
+	}
+
+	if incnwait == work.nproc && !gcMarkWorkAvailable(nil) {
+		// This has reached a background completion point. Set
+		// gp.param to a non-nil value to indicate this. It
+		// doesn't matter what we set it to (it just has to be
+		// a valid pointer).
+		gp.param = unsafe.Pointer(gp)
+	}
+	now := nanotime()
+	duration := now - startTime
+	_p_ := gp.m.p.ptr()
+	_p_.gcAssistTime += duration
+	if trackLimiterEvent {
+		_p_.limiterEvent.stop(limiterEventMarkAssist, now)
+	}
+	if _p_.gcAssistTime > gcAssistTimeSlack {
+		gcController.assistTime.Add(_p_.gcAssistTime)
+		gcCPULimiter.update(now)
+		_p_.gcAssistTime = 0
+	}
+}
+
+// gcWakeAllAssists wakes all currently blocked assists. This is used
+// at the end of a GC cycle. gcBlackenEnabled must be false to prevent
+// new assists from going to sleep after this point.
+func gcWakeAllAssists() {
+	lock(&work.assistQueue.lock)
+	list := work.assistQueue.q.popList()
+	injectglist(&list)
+	unlock(&work.assistQueue.lock)
+}
+
+// gcParkAssist puts the current goroutine on the assist queue and parks.
+//
+// gcParkAssist reports whether the assist is now satisfied. If it
+// returns false, the caller must retry the assist.
+func gcParkAssist() bool {
+	lock(&work.assistQueue.lock)
+	// If the GC cycle finished while we were getting the lock,
+	// exit the assist. The cycle can't finish while we hold the
+	// lock.
+	if atomic.Load(&gcBlackenEnabled) == 0 {
+		unlock(&work.assistQueue.lock)
+		return true
+	}
+
+	gp := getg()
+	oldList := work.assistQueue.q
+	work.assistQueue.q.pushBack(gp)
+
+	// Recheck for background credit now that this G is in
+	// the queue, but can still back out. This avoids a
+	// race in case background marking has flushed more
+	// credit since we checked above.
+	if atomic.Loadint64(&gcController.bgScanCredit) > 0 {
+		work.assistQueue.q = oldList
+		if oldList.tail != 0 {
+			oldList.tail.ptr().schedlink.set(nil)
+		}
+		unlock(&work.assistQueue.lock)
+		return false
+	}
+	// Park.
+	goparkunlock(&work.assistQueue.lock, waitReasonGCAssistWait, traceEvGoBlockGC, 2)
+	return true
+}
+
+// gcFlushBgCredit flushes scanWork units of background scan work
+// credit. This first satisfies blocked assists on the
+// work.assistQueue and then flushes any remaining credit to
+// gcController.bgScanCredit.
+//
+// Write barriers are disallowed because this is used by gcDrain after
+// it has ensured that all work is drained and this must preserve that
+// condition.
+//
+//go:nowritebarrierrec
+func gcFlushBgCredit(scanWork int64) {
+	if work.assistQueue.q.empty() {
+		// Fast path; there are no blocked assists. There's a
+		// small window here where an assist may add itself to
+		// the blocked queue and park. If that happens, we'll
+		// just get it on the next flush.
+		atomic.Xaddint64(&gcController.bgScanCredit, scanWork)
+		return
+	}
+
+	assistBytesPerWork := gcController.assistBytesPerWork.Load()
+	scanBytes := int64(float64(scanWork) * assistBytesPerWork)
+
+	lock(&work.assistQueue.lock)
+	for !work.assistQueue.q.empty() && scanBytes > 0 {
+		gp := work.assistQueue.q.pop()
+		// Note that gp.gcAssistBytes is negative because gp
+		// is in debt. Think carefully about the signs below.
+		if scanBytes+gp.gcAssistBytes >= 0 {
+			// Satisfy this entire assist debt.
+			scanBytes += gp.gcAssistBytes
+			gp.gcAssistBytes = 0
+			// It's important that we *not* put gp in
+			// runnext. Otherwise, it's possible for user
+			// code to exploit the GC worker's high
+			// scheduler priority to get itself always run
+			// before other goroutines and always in the
+			// fresh quantum started by GC.
+			ready(gp, 0, false)
+		} else {
+			// Partially satisfy this assist.
+			gp.gcAssistBytes += scanBytes
+			scanBytes = 0
+			// As a heuristic, we move this assist to the
+			// back of the queue so that large assists
+			// can't clog up the assist queue and
+			// substantially delay small assists.
+			work.assistQueue.q.pushBack(gp)
+			break
+		}
+	}
+
+	if scanBytes > 0 {
+		// Convert from scan bytes back to work.
+		assistWorkPerByte := gcController.assistWorkPerByte.Load()
+		scanWork = int64(float64(scanBytes) * assistWorkPerByte)
+		atomic.Xaddint64(&gcController.bgScanCredit, scanWork)
+	}
+	unlock(&work.assistQueue.lock)
+}
+
+// scanstack scans gp's stack, greying all pointers found on the stack.
+//
+// Returns the amount of scan work performed, but doesn't update
+// gcController.stackScanWork or flush any credit. Any background credit produced
+// by this function should be flushed by its caller. scanstack itself can't
+// safely flush because it may result in trying to wake up a goroutine that
+// was just scanned, resulting in a self-deadlock.
+//
+// scanstack will also shrink the stack if it is safe to do so. If it
+// is not, it schedules a stack shrink for the next synchronous safe
+// point.
+//
+// scanstack is marked go:systemstack because it must not be preempted
+// while using a workbuf.
+//
+//go:nowritebarrier
+//go:systemstack
+func scanstack(gp *g, gcw *gcWork) int64 {
+	if readgstatus(gp)&_Gscan == 0 {
+		print("runtime:scanstack: gp=", gp, ", goid=", gp.goid, ", gp->atomicstatus=", hex(readgstatus(gp)), "\n")
+		throw("scanstack - bad status")
+	}
+
+	switch readgstatus(gp) &^ _Gscan {
+	default:
+		print("runtime: gp=", gp, ", goid=", gp.goid, ", gp->atomicstatus=", readgstatus(gp), "\n")
+		throw("mark - bad status")
+	case _Gdead:
+		return 0
+	case _Grunning:
+		print("runtime: gp=", gp, ", goid=", gp.goid, ", gp->atomicstatus=", readgstatus(gp), "\n")
+		throw("scanstack: goroutine not stopped")
+	case _Grunnable, _Gsyscall, _Gwaiting:
+		// ok
+	}
+
+	if gp == getg() {
+		throw("can't scan our own stack")
+	}
+
+	// scannedSize is the amount of work we'll be reporting.
+	//
+	// It is less than the allocated size (which is hi-lo).
+	var sp uintptr
+	if gp.syscallsp != 0 {
+		sp = gp.syscallsp // If in a system call this is the stack pointer (gp.sched.sp can be 0 in this case on Windows).
+	} else {
+		sp = gp.sched.sp
+	}
+	scannedSize := gp.stack.hi - sp
+
+	// Keep statistics for initial stack size calculation.
+	// Note that this accumulates the scanned size, not the allocated size.
+	p := getg().m.p.ptr()
+	p.scannedStackSize += uint64(scannedSize)
+	p.scannedStacks++
+
+	if isShrinkStackSafe(gp) {
+		// Shrink the stack if not much of it is being used.
+		shrinkstack(gp)
+	} else {
+		// Otherwise, shrink the stack at the next sync safe point.
+		gp.preemptShrink = true
+	}
+
+	var state stackScanState
+	state.stack = gp.stack
+
+	if stackTraceDebug {
+		println("stack trace goroutine", gp.goid)
+	}
+
+	if debugScanConservative && gp.asyncSafePoint {
+		print("scanning async preempted goroutine ", gp.goid, " stack [", hex(gp.stack.lo), ",", hex(gp.stack.hi), ")\n")
+	}
+
+	// Scan the saved context register. This is effectively a live
+	// register that gets moved back and forth between the
+	// register and sched.ctxt without a write barrier.
+	if gp.sched.ctxt != nil {
+		scanblock(uintptr(unsafe.Pointer(&gp.sched.ctxt)), goarch.PtrSize, &oneptrmask[0], gcw, &state)
+	}
+
+	// Scan the stack. Accumulate a list of stack objects.
+	scanframe := func(frame *stkframe, unused unsafe.Pointer) bool {
+		scanframeworker(frame, &state, gcw)
+		return true
+	}
+	gentraceback(^uintptr(0), ^uintptr(0), 0, gp, 0, nil, 0x7fffffff, scanframe, nil, 0)
+
+	// Find additional pointers that point into the stack from the heap.
+	// Currently this includes defers and panics. See also function copystack.
+
+	// Find and trace other pointers in defer records.
+	for d := gp._defer; d != nil; d = d.link {
+		if d.fn != nil {
+			// Scan the func value, which could be a stack allocated closure.
+			// See issue 30453.
+			scanblock(uintptr(unsafe.Pointer(&d.fn)), goarch.PtrSize, &oneptrmask[0], gcw, &state)
+		}
+		if d.link != nil {
+			// The link field of a stack-allocated defer record might point
+			// to a heap-allocated defer record. Keep that heap record live.
+			scanblock(uintptr(unsafe.Pointer(&d.link)), goarch.PtrSize, &oneptrmask[0], gcw, &state)
+		}
+		// Retain defers records themselves.
+		// Defer records might not be reachable from the G through regular heap
+		// tracing because the defer linked list might weave between the stack and the heap.
+		if d.heap {
+			scanblock(uintptr(unsafe.Pointer(&d)), goarch.PtrSize, &oneptrmask[0], gcw, &state)
+		}
+	}
+	if gp._panic != nil {
+		// Panics are always stack allocated.
+		state.putPtr(uintptr(unsafe.Pointer(gp._panic)), false)
+	}
+
+	// Find and scan all reachable stack objects.
+	//
+	// The state's pointer queue prioritizes precise pointers over
+	// conservative pointers so that we'll prefer scanning stack
+	// objects precisely.
+	state.buildIndex()
+	for {
+		p, conservative := state.getPtr()
+		if p == 0 {
+			break
+		}
+		obj := state.findObject(p)
+		if obj == nil {
+			continue
+		}
+		r := obj.r
+		if r == nil {
+			// We've already scanned this object.
+			continue
+		}
+		obj.setRecord(nil) // Don't scan it again.
+		if stackTraceDebug {
+			printlock()
+			print("  live stkobj at", hex(state.stack.lo+uintptr(obj.off)), "of size", obj.size)
+			if conservative {
+				print(" (conservative)")
+			}
+			println()
+			printunlock()
+		}
+		gcdata := r.gcdata()
+		var s *mspan
+		if r.useGCProg() {
+			// This path is pretty unlikely, an object large enough
+			// to have a GC program allocated on the stack.
+			// We need some space to unpack the program into a straight
+			// bitmask, which we allocate/free here.
+			// TODO: it would be nice if there were a way to run a GC
+			// program without having to store all its bits. We'd have
+			// to change from a Lempel-Ziv style program to something else.
+			// Or we can forbid putting objects on stacks if they require
+			// a gc program (see issue 27447).
+			s = materializeGCProg(r.ptrdata(), gcdata)
+			gcdata = (*byte)(unsafe.Pointer(s.startAddr))
+		}
+
+		b := state.stack.lo + uintptr(obj.off)
+		if conservative {
+			scanConservative(b, r.ptrdata(), gcdata, gcw, &state)
+		} else {
+			scanblock(b, r.ptrdata(), gcdata, gcw, &state)
+		}
+
+		if s != nil {
+			dematerializeGCProg(s)
+		}
+	}
+
+	// Deallocate object buffers.
+	// (Pointer buffers were all deallocated in the loop above.)
+	for state.head != nil {
+		x := state.head
+		state.head = x.next
+		if stackTraceDebug {
+			for i := 0; i < x.nobj; i++ {
+				obj := &x.obj[i]
+				if obj.r == nil { // reachable
+					continue
+				}
+				println("  dead stkobj at", hex(gp.stack.lo+uintptr(obj.off)), "of size", obj.r.size)
+				// Note: not necessarily really dead - only reachable-from-ptr dead.
+			}
+		}
+		x.nobj = 0
+		putempty((*workbuf)(unsafe.Pointer(x)))
+	}
+	if state.buf != nil || state.cbuf != nil || state.freeBuf != nil {
+		throw("remaining pointer buffers")
+	}
+	return int64(scannedSize)
+}
+
+// Scan a stack frame: local variables and function arguments/results.
+//
+//go:nowritebarrier
+func scanframeworker(frame *stkframe, state *stackScanState, gcw *gcWork) {
+	if _DebugGC > 1 && frame.continpc != 0 {
+		print("scanframe ", funcname(frame.fn), "\n")
+	}
+
+	isAsyncPreempt := frame.fn.valid() && frame.fn.funcID == funcID_asyncPreempt
+	isDebugCall := frame.fn.valid() && frame.fn.funcID == funcID_debugCallV2
+	if state.conservative || isAsyncPreempt || isDebugCall {
+		if debugScanConservative {
+			println("conservatively scanning function", funcname(frame.fn), "at PC", hex(frame.continpc))
+		}
+
+		// Conservatively scan the frame. Unlike the precise
+		// case, this includes the outgoing argument space
+		// since we may have stopped while this function was
+		// setting up a call.
+		//
+		// TODO: We could narrow this down if the compiler
+		// produced a single map per function of stack slots
+		// and registers that ever contain a pointer.
+		if frame.varp != 0 {
+			size := frame.varp - frame.sp
+			if size > 0 {
+				scanConservative(frame.sp, size, nil, gcw, state)
+			}
+		}
+
+		// Scan arguments to this frame.
+		if frame.arglen != 0 {
+			// TODO: We could pass the entry argument map
+			// to narrow this down further.
+			scanConservative(frame.argp, frame.arglen, nil, gcw, state)
+		}
+
+		if isAsyncPreempt || isDebugCall {
+			// This function's frame contained the
+			// registers for the asynchronously stopped
+			// parent frame. Scan the parent
+			// conservatively.
+			state.conservative = true
+		} else {
+			// We only wanted to scan those two frames
+			// conservatively. Clear the flag for future
+			// frames.
+			state.conservative = false
+		}
+		return
+	}
+
+	locals, args, objs := getStackMap(frame, &state.cache, false)
+
+	// Scan local variables if stack frame has been allocated.
+	if locals.n > 0 {
+		size := uintptr(locals.n) * goarch.PtrSize
+		scanblock(frame.varp-size, size, locals.bytedata, gcw, state)
+	}
+
+	// Scan arguments.
+	if args.n > 0 {
+		scanblock(frame.argp, uintptr(args.n)*goarch.PtrSize, args.bytedata, gcw, state)
+	}
+
+	// Add all stack objects to the stack object list.
+	if frame.varp != 0 {
+		// varp is 0 for defers, where there are no locals.
+		// In that case, there can't be a pointer to its args, either.
+		// (And all args would be scanned above anyway.)
+		for i := range objs {
+			obj := &objs[i]
+			off := obj.off
+			base := frame.varp // locals base pointer
+			if off >= 0 {
+				base = frame.argp // arguments and return values base pointer
+			}
+			ptr := base + uintptr(off)
+			if ptr < frame.sp {
+				// object hasn't been allocated in the frame yet.
+				continue
+			}
+			if stackTraceDebug {
+				println("stkobj at", hex(ptr), "of size", obj.size)
+			}
+			state.addObject(ptr, obj)
+		}
+	}
+}
+
+type gcDrainFlags int
+
+const (
+	gcDrainUntilPreempt gcDrainFlags = 1 << iota
+	gcDrainFlushBgCredit
+	gcDrainIdle
+	gcDrainFractional
+)
+
+// gcDrain scans roots and objects in work buffers, blackening grey
+// objects until it is unable to get more work. It may return before
+// GC is done; it's the caller's responsibility to balance work from
+// other Ps.
+//
+// If flags&gcDrainUntilPreempt != 0, gcDrain returns when g.preempt
+// is set.
+//
+// If flags&gcDrainIdle != 0, gcDrain returns when there is other work
+// to do.
+//
+// If flags&gcDrainFractional != 0, gcDrain self-preempts when
+// pollFractionalWorkerExit() returns true. This implies
+// gcDrainNoBlock.
+//
+// If flags&gcDrainFlushBgCredit != 0, gcDrain flushes scan work
+// credit to gcController.bgScanCredit every gcCreditSlack units of
+// scan work.
+//
+// gcDrain will always return if there is a pending STW.
+//
+//go:nowritebarrier
+func gcDrain(gcw *gcWork, flags gcDrainFlags) {
+	if !writeBarrier.needed {
+		throw("gcDrain phase incorrect")
+	}
+
+	gp := getg().m.curg
+	preemptible := flags&gcDrainUntilPreempt != 0
+	flushBgCredit := flags&gcDrainFlushBgCredit != 0
+	idle := flags&gcDrainIdle != 0
+
+	initScanWork := gcw.heapScanWork
+
+	// checkWork is the scan work before performing the next
+	// self-preempt check.
+	checkWork := int64(1<<63 - 1)
+	var check func() bool
+	if flags&(gcDrainIdle|gcDrainFractional) != 0 {
+		checkWork = initScanWork + drainCheckThreshold
+		if idle {
+			check = pollWork
+		} else if flags&gcDrainFractional != 0 {
+			check = pollFractionalWorkerExit
+		}
+	}
+
+	// Drain root marking jobs.
+	if work.markrootNext < work.markrootJobs {
+		// Stop if we're preemptible or if someone wants to STW.
+		for !(gp.preempt && (preemptible || atomic.Load(&sched.gcwaiting) != 0)) {
+			job := atomic.Xadd(&work.markrootNext, +1) - 1
+			if job >= work.markrootJobs {
+				break
+			}
+			markroot(gcw, job, flushBgCredit)
+			if check != nil && check() {
+				goto done
+			}
+		}
+	}
+
+	// Drain heap marking jobs.
+	// Stop if we're preemptible or if someone wants to STW.
+	for !(gp.preempt && (preemptible || atomic.Load(&sched.gcwaiting) != 0)) {
+		// Try to keep work available on the global queue. We used to
+		// check if there were waiting workers, but it's better to
+		// just keep work available than to make workers wait. In the
+		// worst case, we'll do O(log(_WorkbufSize)) unnecessary
+		// balances.
+		if work.full == 0 {
+			gcw.balance()
+		}
+
+		b := gcw.tryGetFast()
+		if b == 0 {
+			b = gcw.tryGet()
+			if b == 0 {
+				// Flush the write barrier
+				// buffer; this may create
+				// more work.
+				wbBufFlush(nil, 0)
+				b = gcw.tryGet()
+			}
+		}
+		if b == 0 {
+			// Unable to get work.
+			break
+		}
+		scanobject(b, gcw)
+
+		// Flush background scan work credit to the global
+		// account if we've accumulated enough locally so
+		// mutator assists can draw on it.
+		if gcw.heapScanWork >= gcCreditSlack {
+			gcController.heapScanWork.Add(gcw.heapScanWork)
+			if flushBgCredit {
+				gcFlushBgCredit(gcw.heapScanWork - initScanWork)
+				initScanWork = 0
+			}
+			checkWork -= gcw.heapScanWork
+			gcw.heapScanWork = 0
+
+			if checkWork <= 0 {
+				checkWork += drainCheckThreshold
+				if check != nil && check() {
+					break
+				}
+			}
+		}
+	}
+
+done:
+	// Flush remaining scan work credit.
+	if gcw.heapScanWork > 0 {
+		gcController.heapScanWork.Add(gcw.heapScanWork)
+		if flushBgCredit {
+			gcFlushBgCredit(gcw.heapScanWork - initScanWork)
+		}
+		gcw.heapScanWork = 0
+	}
+}
+
+// gcDrainN blackens grey objects until it has performed roughly
+// scanWork units of scan work or the G is preempted. This is
+// best-effort, so it may perform less work if it fails to get a work
+// buffer. Otherwise, it will perform at least n units of work, but
+// may perform more because scanning is always done in whole object
+// increments. It returns the amount of scan work performed.
+//
+// The caller goroutine must be in a preemptible state (e.g.,
+// _Gwaiting) to prevent deadlocks during stack scanning. As a
+// consequence, this must be called on the system stack.
+//
+//go:nowritebarrier
+//go:systemstack
+func gcDrainN(gcw *gcWork, scanWork int64) int64 {
+	if !writeBarrier.needed {
+		throw("gcDrainN phase incorrect")
+	}
+
+	// There may already be scan work on the gcw, which we don't
+	// want to claim was done by this call.
+	workFlushed := -gcw.heapScanWork
+
+	// In addition to backing out because of a preemption, back out
+	// if the GC CPU limiter is enabled.
+	gp := getg().m.curg
+	for !gp.preempt && !gcCPULimiter.limiting() && workFlushed+gcw.heapScanWork < scanWork {
+		// See gcDrain comment.
+		if work.full == 0 {
+			gcw.balance()
+		}
+
+		b := gcw.tryGetFast()
+		if b == 0 {
+			b = gcw.tryGet()
+			if b == 0 {
+				// Flush the write barrier buffer;
+				// this may create more work.
+				wbBufFlush(nil, 0)
+				b = gcw.tryGet()
+			}
+		}
+
+		if b == 0 {
+			// Try to do a root job.
+			if work.markrootNext < work.markrootJobs {
+				job := atomic.Xadd(&work.markrootNext, +1) - 1
+				if job < work.markrootJobs {
+					workFlushed += markroot(gcw, job, false)
+					continue
+				}
+			}
+			// No heap or root jobs.
+			break
+		}
+
+		scanobject(b, gcw)
+
+		// Flush background scan work credit.
+		if gcw.heapScanWork >= gcCreditSlack {
+			gcController.heapScanWork.Add(gcw.heapScanWork)
+			workFlushed += gcw.heapScanWork
+			gcw.heapScanWork = 0
+		}
+	}
+
+	// Unlike gcDrain, there's no need to flush remaining work
+	// here because this never flushes to bgScanCredit and
+	// gcw.dispose will flush any remaining work to scanWork.
+
+	return workFlushed + gcw.heapScanWork
+}
+
+// scanblock scans b as scanobject would, but using an explicit
+// pointer bitmap instead of the heap bitmap.
+//
+// This is used to scan non-heap roots, so it does not update
+// gcw.bytesMarked or gcw.heapScanWork.
+//
+// If stk != nil, possible stack pointers are also reported to stk.putPtr.
+//
+//go:nowritebarrier
+func scanblock(b0, n0 uintptr, ptrmask *uint8, gcw *gcWork, stk *stackScanState) {
+	// Use local copies of original parameters, so that a stack trace
+	// due to one of the throws below shows the original block
+	// base and extent.
+	b := b0
+	n := n0
+
+	for i := uintptr(0); i < n; {
+		// Find bits for the next word.
+		bits := uint32(*addb(ptrmask, i/(goarch.PtrSize*8)))
+		if bits == 0 {
+			i += goarch.PtrSize * 8
+			continue
+		}
+		for j := 0; j < 8 && i < n; j++ {
+			if bits&1 != 0 {
+				// Same work as in scanobject; see comments there.
+				p := *(*uintptr)(unsafe.Pointer(b + i))
+				if p != 0 {
+					if obj, span, objIndex := findObject(p, b, i); obj != 0 {
+						greyobject(obj, b, i, span, gcw, objIndex)
+					} else if stk != nil && p >= stk.stack.lo && p < stk.stack.hi {
+						stk.putPtr(p, false)
+					}
+				}
+			}
+			bits >>= 1
+			i += goarch.PtrSize
+		}
+	}
+}
+
+// scanobject scans the object starting at b, adding pointers to gcw.
+// b must point to the beginning of a heap object or an oblet.
+// scanobject consults the GC bitmap for the pointer mask and the
+// spans for the size of the object.
+//
+//go:nowritebarrier
+func scanobject(b uintptr, gcw *gcWork) {
+	// Prefetch object before we scan it.
+	//
+	// This will overlap fetching the beginning of the object with initial
+	// setup before we start scanning the object.
+	sys.Prefetch(b)
+
+	// Find the bits for b and the size of the object at b.
+	//
+	// b is either the beginning of an object, in which case this
+	// is the size of the object to scan, or it points to an
+	// oblet, in which case we compute the size to scan below.
+	hbits := heapBitsForAddr(b)
+	s := spanOfUnchecked(b)
+	n := s.elemsize
+	if n == 0 {
+		throw("scanobject n == 0")
+	}
+
+	if n > maxObletBytes {
+		// Large object. Break into oblets for better
+		// parallelism and lower latency.
+		if b == s.base() {
+			// It's possible this is a noscan object (not
+			// from greyobject, but from other code
+			// paths), in which case we must *not* enqueue
+			// oblets since their bitmaps will be
+			// uninitialized.
+			if s.spanclass.noscan() {
+				// Bypass the whole scan.
+				gcw.bytesMarked += uint64(n)
+				return
+			}
+
+			// Enqueue the other oblets to scan later.
+			// Some oblets may be in b's scalar tail, but
+			// these will be marked as "no more pointers",
+			// so we'll drop out immediately when we go to
+			// scan those.
+			for oblet := b + maxObletBytes; oblet < s.base()+s.elemsize; oblet += maxObletBytes {
+				if !gcw.putFast(oblet) {
+					gcw.put(oblet)
+				}
+			}
+		}
+
+		// Compute the size of the oblet. Since this object
+		// must be a large object, s.base() is the beginning
+		// of the object.
+		n = s.base() + s.elemsize - b
+		if n > maxObletBytes {
+			n = maxObletBytes
+		}
+	}
+
+	var i uintptr
+	for i = 0; i < n; i, hbits = i+goarch.PtrSize, hbits.next() {
+		// Load bits once. See CL 22712 and issue 16973 for discussion.
+		bits := hbits.bits()
+		if bits&bitScan == 0 {
+			break // no more pointers in this object
+		}
+		if bits&bitPointer == 0 {
+			continue // not a pointer
+		}
+
+		// Work here is duplicated in scanblock and above.
+		// If you make changes here, make changes there too.
+		obj := *(*uintptr)(unsafe.Pointer(b + i))
+
+		// At this point we have extracted the next potential pointer.
+		// Quickly filter out nil and pointers back to the current object.
+		if obj != 0 && obj-b >= n {
+			// Test if obj points into the Go heap and, if so,
+			// mark the object.
+			//
+			// Note that it's possible for findObject to
+			// fail if obj points to a just-allocated heap
+			// object because of a race with growing the
+			// heap. In this case, we know the object was
+			// just allocated and hence will be marked by
+			// allocation itself.
+			if obj, span, objIndex := findObject(obj, b, i); obj != 0 {
+				greyobject(obj, b, i, span, gcw, objIndex)
+			}
+		}
+	}
+	gcw.bytesMarked += uint64(n)
+	gcw.heapScanWork += int64(i)
+}
+
+// scanConservative scans block [b, b+n) conservatively, treating any
+// pointer-like value in the block as a pointer.
+//
+// If ptrmask != nil, only words that are marked in ptrmask are
+// considered as potential pointers.
+//
+// If state != nil, it's assumed that [b, b+n) is a block in the stack
+// and may contain pointers to stack objects.
+func scanConservative(b, n uintptr, ptrmask *uint8, gcw *gcWork, state *stackScanState) {
+	if debugScanConservative {
+		printlock()
+		print("conservatively scanning [", hex(b), ",", hex(b+n), ")\n")
+		hexdumpWords(b, b+n, func(p uintptr) byte {
+			if ptrmask != nil {
+				word := (p - b) / goarch.PtrSize
+				bits := *addb(ptrmask, word/8)
+				if (bits>>(word%8))&1 == 0 {
+					return '$'
+				}
+			}
+
+			val := *(*uintptr)(unsafe.Pointer(p))
+			if state != nil && state.stack.lo <= val && val < state.stack.hi {
+				return '@'
+			}
+
+			span := spanOfHeap(val)
+			if span == nil {
+				return ' '
+			}
+			idx := span.objIndex(val)
+			if span.isFree(idx) {
+				return ' '
+			}
+			return '*'
+		})
+		printunlock()
+	}
+
+	for i := uintptr(0); i < n; i += goarch.PtrSize {
+		if ptrmask != nil {
+			word := i / goarch.PtrSize
+			bits := *addb(ptrmask, word/8)
+			if bits == 0 {
+				// Skip 8 words (the loop increment will do the 8th)
+				//
+				// This must be the first time we've
+				// seen this word of ptrmask, so i
+				// must be 8-word-aligned, but check
+				// our reasoning just in case.
+				if i%(goarch.PtrSize*8) != 0 {
+					throw("misaligned mask")
+				}
+				i += goarch.PtrSize*8 - goarch.PtrSize
+				continue
+			}
+			if (bits>>(word%8))&1 == 0 {
+				continue
+			}
+		}
+
+		val := *(*uintptr)(unsafe.Pointer(b + i))
+
+		// Check if val points into the stack.
+		if state != nil && state.stack.lo <= val && val < state.stack.hi {
+			// val may point to a stack object. This
+			// object may be dead from last cycle and
+			// hence may contain pointers to unallocated
+			// objects, but unlike heap objects we can't
+			// tell if it's already dead. Hence, if all
+			// pointers to this object are from
+			// conservative scanning, we have to scan it
+			// defensively, too.
+			state.putPtr(val, true)
+			continue
+		}
+
+		// Check if val points to a heap span.
+		span := spanOfHeap(val)
+		if span == nil {
+			continue
+		}
+
+		// Check if val points to an allocated object.
+		idx := span.objIndex(val)
+		if span.isFree(idx) {
+			continue
+		}
+
+		// val points to an allocated object. Mark it.
+		obj := span.base() + idx*span.elemsize
+		greyobject(obj, b, i, span, gcw, idx)
+	}
+}
+
+// Shade the object if it isn't already.
+// The object is not nil and known to be in the heap.
+// Preemption must be disabled.
+//
+//go:nowritebarrier
+func shade(b uintptr) {
+	if obj, span, objIndex := findObject(b, 0, 0); obj != 0 {
+		gcw := &getg().m.p.ptr().gcw
+		greyobject(obj, 0, 0, span, gcw, objIndex)
+	}
+}
+
+// obj is the start of an object with mark mbits.
+// If it isn't already marked, mark it and enqueue into gcw.
+// base and off are for debugging only and could be removed.
+//
+// See also wbBufFlush1, which partially duplicates this logic.
+//
+//go:nowritebarrierrec
+func greyobject(obj, base, off uintptr, span *mspan, gcw *gcWork, objIndex uintptr) {
+	// obj should be start of allocation, and so must be at least pointer-aligned.
+	if obj&(goarch.PtrSize-1) != 0 {
+		throw("greyobject: obj not pointer-aligned")
+	}
+	mbits := span.markBitsForIndex(objIndex)
+
+	if useCheckmark {
+		if setCheckmark(obj, base, off, mbits) {
+			// Already marked.
+			return
+		}
+	} else {
+		if debug.gccheckmark > 0 && span.isFree(objIndex) {
+			print("runtime: marking free object ", hex(obj), " found at *(", hex(base), "+", hex(off), ")\n")
+			gcDumpObject("base", base, off)
+			gcDumpObject("obj", obj, ^uintptr(0))
+			getg().m.traceback = 2
+			throw("marking free object")
+		}
+
+		// If marked we have nothing to do.
+		if mbits.isMarked() {
+			return
+		}
+		mbits.setMarked()
+
+		// Mark span.
+		arena, pageIdx, pageMask := pageIndexOf(span.base())
+		if arena.pageMarks[pageIdx]&pageMask == 0 {
+			atomic.Or8(&arena.pageMarks[pageIdx], pageMask)
+		}
+
+		// If this is a noscan object, fast-track it to black
+		// instead of greying it.
+		if span.spanclass.noscan() {
+			gcw.bytesMarked += uint64(span.elemsize)
+			return
+		}
+	}
+
+	// We're adding obj to P's local workbuf, so it's likely
+	// this object will be processed soon by the same P.
+	// Even if the workbuf gets flushed, there will likely still be
+	// some benefit on platforms with inclusive shared caches.
+	sys.Prefetch(obj)
+	// Queue the obj for scanning.
+	if !gcw.putFast(obj) {
+		gcw.put(obj)
+	}
+}
+
+// gcDumpObject dumps the contents of obj for debugging and marks the
+// field at byte offset off in obj.
+func gcDumpObject(label string, obj, off uintptr) {
+	s := spanOf(obj)
+	print(label, "=", hex(obj))
+	if s == nil {
+		print(" s=nil\n")
+		return
+	}
+	print(" s.base()=", hex(s.base()), " s.limit=", hex(s.limit), " s.spanclass=", s.spanclass, " s.elemsize=", s.elemsize, " s.state=")
+	if state := s.state.get(); 0 <= state && int(state) < len(mSpanStateNames) {
+		print(mSpanStateNames[state], "\n")
+	} else {
+		print("unknown(", state, ")\n")
+	}
+
+	skipped := false
+	size := s.elemsize
+	if s.state.get() == mSpanManual && size == 0 {
+		// We're printing something from a stack frame. We
+		// don't know how big it is, so just show up to an
+		// including off.
+		size = off + goarch.PtrSize
+	}
+	for i := uintptr(0); i < size; i += goarch.PtrSize {
+		// For big objects, just print the beginning (because
+		// that usually hints at the object's type) and the
+		// fields around off.
+		if !(i < 128*goarch.PtrSize || off-16*goarch.PtrSize < i && i < off+16*goarch.PtrSize) {
+			skipped = true
+			continue
+		}
+		if skipped {
+			print(" ...\n")
+			skipped = false
+		}
+		print(" *(", label, "+", i, ") = ", hex(*(*uintptr)(unsafe.Pointer(obj + i))))
+		if i == off {
+			print(" <==")
+		}
+		print("\n")
+	}
+	if skipped {
+		print(" ...\n")
+	}
+}
+
+// gcmarknewobject marks a newly allocated object black. obj must
+// not contain any non-nil pointers.
+//
+// This is nosplit so it can manipulate a gcWork without preemption.
+//
+//go:nowritebarrier
+//go:nosplit
+func gcmarknewobject(span *mspan, obj, size, scanSize uintptr) {
+	if useCheckmark { // The world should be stopped so this should not happen.
+		throw("gcmarknewobject called while doing checkmark")
+	}
+
+	// Mark object.
+	objIndex := span.objIndex(obj)
+	span.markBitsForIndex(objIndex).setMarked()
+
+	// Mark span.
+	arena, pageIdx, pageMask := pageIndexOf(span.base())
+	if arena.pageMarks[pageIdx]&pageMask == 0 {
+		atomic.Or8(&arena.pageMarks[pageIdx], pageMask)
+	}
+
+	gcw := &getg().m.p.ptr().gcw
+	gcw.bytesMarked += uint64(size)
+}
+
+// gcMarkTinyAllocs greys all active tiny alloc blocks.
+//
+// The world must be stopped.
+func gcMarkTinyAllocs() {
+	assertWorldStopped()
+
+	for _, p := range allp {
+		c := p.mcache
+		if c == nil || c.tiny == 0 {
+			continue
+		}
+		_, span, objIndex := findObject(c.tiny, 0, 0)
+		gcw := &p.gcw
+		greyobject(c.tiny, 0, 0, span, gcw, objIndex)
+	}
+}
diff --git a/contrib/go/_std_1.19/src/runtime/mgcpacer.go b/contrib/go/_std_1.19/src/runtime/mgcpacer.go
new file mode 100644
index 0000000000..2d9fd27748
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/mgcpacer.go
@@ -0,0 +1,1579 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"internal/cpu"
+	"internal/goexperiment"
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+// go119MemoryLimitSupport is a feature flag for a number of changes
+// related to the memory limit feature (#48409). Disabling this flag
+// disables those features, as well as the memory limit mechanism,
+// which becomes a no-op.
+const go119MemoryLimitSupport = true
+
+const (
+	// gcGoalUtilization is the goal CPU utilization for
+	// marking as a fraction of GOMAXPROCS.
+	//
+	// Increasing the goal utilization will shorten GC cycles as the GC
+	// has more resources behind it, lessening costs from the write barrier,
+	// but comes at the cost of increasing mutator latency.
+	gcGoalUtilization = gcBackgroundUtilization
+
+	// gcBackgroundUtilization is the fixed CPU utilization for background
+	// marking. It must be <= gcGoalUtilization. The difference between
+	// gcGoalUtilization and gcBackgroundUtilization will be made up by
+	// mark assists. The scheduler will aim to use within 50% of this
+	// goal.
+	//
+	// As a general rule, there's little reason to set gcBackgroundUtilization
+	// < gcGoalUtilization. One reason might be in mostly idle applications,
+	// where goroutines are unlikely to assist at all, so the actual
+	// utilization will be lower than the goal. But this is moot point
+	// because the idle mark workers already soak up idle CPU resources.
+	// These two values are still kept separate however because they are
+	// distinct conceptually, and in previous iterations of the pacer the
+	// distinction was more important.
+	gcBackgroundUtilization = 0.25
+
+	// gcCreditSlack is the amount of scan work credit that can
+	// accumulate locally before updating gcController.heapScanWork and,
+	// optionally, gcController.bgScanCredit. Lower values give a more
+	// accurate assist ratio and make it more likely that assists will
+	// successfully steal background credit. Higher values reduce memory
+	// contention.
+	gcCreditSlack = 2000
+
+	// gcAssistTimeSlack is the nanoseconds of mutator assist time that
+	// can accumulate on a P before updating gcController.assistTime.
+	gcAssistTimeSlack = 5000
+
+	// gcOverAssistWork determines how many extra units of scan work a GC
+	// assist does when an assist happens. This amortizes the cost of an
+	// assist by pre-paying for this many bytes of future allocations.
+	gcOverAssistWork = 64 << 10
+
+	// defaultHeapMinimum is the value of heapMinimum for GOGC==100.
+	defaultHeapMinimum = (goexperiment.HeapMinimum512KiBInt)*(512<<10) +
+		(1-goexperiment.HeapMinimum512KiBInt)*(4<<20)
+
+	// maxStackScanSlack is the bytes of stack space allocated or freed
+	// that can accumulate on a P before updating gcController.stackSize.
+	maxStackScanSlack = 8 << 10
+
+	// memoryLimitHeapGoalHeadroom is the amount of headroom the pacer gives to
+	// the heap goal when operating in the memory-limited regime. That is,
+	// it'll reduce the heap goal by this many extra bytes off of the base
+	// calculation.
+	memoryLimitHeapGoalHeadroom = 1 << 20
+)
+
+func init() {
+	if offset := unsafe.Offsetof(gcController.heapLive); offset%8 != 0 {
+		println(offset)
+		throw("gcController.heapLive not aligned to 8 bytes")
+	}
+}
+
+// gcController implements the GC pacing controller that determines
+// when to trigger concurrent garbage collection and how much marking
+// work to do in mutator assists and background marking.
+//
+// It calculates the ratio between the allocation rate (in terms of CPU
+// time) and the GC scan throughput to determine the heap size at which to
+// trigger a GC cycle such that no GC assists are required to finish on time.
+// This algorithm thus optimizes GC CPU utilization to the dedicated background
+// mark utilization of 25% of GOMAXPROCS by minimizing GC assists.
+// GOMAXPROCS. The high-level design of this algorithm is documented
+// at https://github.com/golang/proposal/blob/master/design/44167-gc-pacer-redesign.md.
+// See https://golang.org/s/go15gcpacing for additional historical context.
+var gcController gcControllerState
+
+type gcControllerState struct {
+	// Initialized from GOGC. GOGC=off means no GC.
+	gcPercent atomic.Int32
+
+	_ uint32 // padding so following 64-bit values are 8-byte aligned
+
+	// memoryLimit is the soft memory limit in bytes.
+	//
+	// Initialized from GOMEMLIMIT. GOMEMLIMIT=off is equivalent to MaxInt64
+	// which means no soft memory limit in practice.
+	//
+	// This is an int64 instead of a uint64 to more easily maintain parity with
+	// the SetMemoryLimit API, which sets a maximum at MaxInt64. This value
+	// should never be negative.
+	memoryLimit atomic.Int64
+
+	// heapMinimum is the minimum heap size at which to trigger GC.
+	// For small heaps, this overrides the usual GOGC*live set rule.
+	//
+	// When there is a very small live set but a lot of allocation, simply
+	// collecting when the heap reaches GOGC*live results in many GC
+	// cycles and high total per-GC overhead. This minimum amortizes this
+	// per-GC overhead while keeping the heap reasonably small.
+	//
+	// During initialization this is set to 4MB*GOGC/100. In the case of
+	// GOGC==0, this will set heapMinimum to 0, resulting in constant
+	// collection even when the heap size is small, which is useful for
+	// debugging.
+	heapMinimum uint64
+
+	// runway is the amount of runway in heap bytes allocated by the
+	// application that we want to give the GC once it starts.
+	//
+	// This is computed from consMark during mark termination.
+	runway atomic.Uint64
+
+	// consMark is the estimated per-CPU consMark ratio for the application.
+	//
+	// It represents the ratio between the application's allocation
+	// rate, as bytes allocated per CPU-time, and the GC's scan rate,
+	// as bytes scanned per CPU-time.
+	// The units of this ratio are (B / cpu-ns) / (B / cpu-ns).
+	//
+	// At a high level, this value is computed as the bytes of memory
+	// allocated (cons) per unit of scan work completed (mark) in a GC
+	// cycle, divided by the CPU time spent on each activity.
+	//
+	// Updated at the end of each GC cycle, in endCycle.
+	consMark float64
+
+	// consMarkController holds the state for the mark-cons ratio
+	// estimation over time.
+	//
+	// Its purpose is to smooth out noisiness in the computation of
+	// consMark; see consMark for details.
+	consMarkController piController
+
+	_ uint32 // Padding for atomics on 32-bit platforms.
+
+	// gcPercentHeapGoal is the goal heapLive for when next GC ends derived
+	// from gcPercent.
+	//
+	// Set to ^uint64(0) if gcPercent is disabled.
+	gcPercentHeapGoal atomic.Uint64
+
+	// sweepDistMinTrigger is the minimum trigger to ensure a minimum
+	// sweep distance.
+	//
+	// This bound is also special because it applies to both the trigger
+	// *and* the goal (all other trigger bounds must be based *on* the goal).
+	//
+	// It is computed ahead of time, at commit time. The theory is that,
+	// absent a sudden change to a parameter like gcPercent, the trigger
+	// will be chosen to always give the sweeper enough headroom. However,
+	// such a change might dramatically and suddenly move up the trigger,
+	// in which case we need to ensure the sweeper still has enough headroom.
+	sweepDistMinTrigger atomic.Uint64
+
+	// triggered is the point at which the current GC cycle actually triggered.
+	// Only valid during the mark phase of a GC cycle, otherwise set to ^uint64(0).
+	//
+	// Updated while the world is stopped.
+	triggered uint64
+
+	// lastHeapGoal is the value of heapGoal at the moment the last GC
+	// ended. Note that this is distinct from the last value heapGoal had,
+	// because it could change if e.g. gcPercent changes.
+	//
+	// Read and written with the world stopped or with mheap_.lock held.
+	lastHeapGoal uint64
+
+	// heapLive is the number of bytes considered live by the GC.
+	// That is: retained by the most recent GC plus allocated
+	// since then. heapLive ≤ memstats.totalAlloc-memstats.totalFree, since
+	// heapAlloc includes unmarked objects that have not yet been swept (and
+	// hence goes up as we allocate and down as we sweep) while heapLive
+	// excludes these objects (and hence only goes up between GCs).
+	//
+	// This is updated atomically without locking. To reduce
+	// contention, this is updated only when obtaining a span from
+	// an mcentral and at this point it counts all of the
+	// unallocated slots in that span (which will be allocated
+	// before that mcache obtains another span from that
+	// mcentral). Hence, it slightly overestimates the "true" live
+	// heap size. It's better to overestimate than to
+	// underestimate because 1) this triggers the GC earlier than
+	// necessary rather than potentially too late and 2) this
+	// leads to a conservative GC rate rather than a GC rate that
+	// is potentially too low.
+	//
+	// Reads should likewise be atomic (or during STW).
+	//
+	// Whenever this is updated, call traceHeapAlloc() and
+	// this gcControllerState's revise() method.
+	heapLive uint64
+
+	// heapScan is the number of bytes of "scannable" heap. This
+	// is the live heap (as counted by heapLive), but omitting
+	// no-scan objects and no-scan tails of objects.
+	//
+	// This value is fixed at the start of a GC cycle, so during a
+	// GC cycle it is safe to read without atomics, and it represents
+	// the maximum scannable heap.
+	heapScan uint64
+
+	// lastHeapScan is the number of bytes of heap that were scanned
+	// last GC cycle. It is the same as heapMarked, but only
+	// includes the "scannable" parts of objects.
+	//
+	// Updated when the world is stopped.
+	lastHeapScan uint64
+
+	// lastStackScan is the number of bytes of stack that were scanned
+	// last GC cycle.
+	lastStackScan uint64
+
+	// maxStackScan is the amount of allocated goroutine stack space in
+	// use by goroutines.
+	//
+	// This number tracks allocated goroutine stack space rather than used
+	// goroutine stack space (i.e. what is actually scanned) because used
+	// goroutine stack space is much harder to measure cheaply. By using
+	// allocated space, we make an overestimate; this is OK, it's better
+	// to conservatively overcount than undercount.
+	//
+	// Read and updated atomically.
+	maxStackScan uint64
+
+	// globalsScan is the total amount of global variable space
+	// that is scannable.
+	//
+	// Read and updated atomically.
+	globalsScan uint64
+
+	// heapMarked is the number of bytes marked by the previous
+	// GC. After mark termination, heapLive == heapMarked, but
+	// unlike heapLive, heapMarked does not change until the
+	// next mark termination.
+	heapMarked uint64
+
+	// heapScanWork is the total heap scan work performed this cycle.
+	// stackScanWork is the total stack scan work performed this cycle.
+	// globalsScanWork is the total globals scan work performed this cycle.
+	//
+	// These are updated atomically during the cycle. Updates occur in
+	// bounded batches, since they are both written and read
+	// throughout the cycle. At the end of the cycle, heapScanWork is how
+	// much of the retained heap is scannable.
+	//
+	// Currently these are measured in bytes. For most uses, this is an
+	// opaque unit of work, but for estimation the definition is important.
+	//
+	// Note that stackScanWork includes only stack space scanned, not all
+	// of the allocated stack.
+	heapScanWork    atomic.Int64
+	stackScanWork   atomic.Int64
+	globalsScanWork atomic.Int64
+
+	// bgScanCredit is the scan work credit accumulated by the
+	// concurrent background scan. This credit is accumulated by
+	// the background scan and stolen by mutator assists. This is
+	// updated atomically. Updates occur in bounded batches, since
+	// it is both written and read throughout the cycle.
+	bgScanCredit int64
+
+	// assistTime is the nanoseconds spent in mutator assists
+	// during this cycle. This is updated atomically, and must also
+	// be updated atomically even during a STW, because it is read
+	// by sysmon. Updates occur in bounded batches, since it is both
+	// written and read throughout the cycle.
+	assistTime atomic.Int64
+
+	// dedicatedMarkTime is the nanoseconds spent in dedicated
+	// mark workers during this cycle. This is updated atomically
+	// at the end of the concurrent mark phase.
+	dedicatedMarkTime int64
+
+	// fractionalMarkTime is the nanoseconds spent in the
+	// fractional mark worker during this cycle. This is updated
+	// atomically throughout the cycle and will be up-to-date if
+	// the fractional mark worker is not currently running.
+	fractionalMarkTime int64
+
+	// idleMarkTime is the nanoseconds spent in idle marking
+	// during this cycle. This is updated atomically throughout
+	// the cycle.
+	idleMarkTime int64
+
+	// markStartTime is the absolute start time in nanoseconds
+	// that assists and background mark workers started.
+	markStartTime int64
+
+	// dedicatedMarkWorkersNeeded is the number of dedicated mark
+	// workers that need to be started. This is computed at the
+	// beginning of each cycle and decremented atomically as
+	// dedicated mark workers get started.
+	dedicatedMarkWorkersNeeded int64
+
+	// idleMarkWorkers is two packed int32 values in a single uint64.
+	// These two values are always updated simultaneously.
+	//
+	// The bottom int32 is the current number of idle mark workers executing.
+	//
+	// The top int32 is the maximum number of idle mark workers allowed to
+	// execute concurrently. Normally, this number is just gomaxprocs. However,
+	// during periodic GC cycles it is set to 0 because the system is idle
+	// anyway; there's no need to go full blast on all of GOMAXPROCS.
+	//
+	// The maximum number of idle mark workers is used to prevent new workers
+	// from starting, but it is not a hard maximum. It is possible (but
+	// exceedingly rare) for the current number of idle mark workers to
+	// transiently exceed the maximum. This could happen if the maximum changes
+	// just after a GC ends, and an M with no P.
+	//
+	// Note that if we have no dedicated mark workers, we set this value to
+	// 1 in this case we only have fractional GC workers which aren't scheduled
+	// strictly enough to ensure GC progress. As a result, idle-priority mark
+	// workers are vital to GC progress in these situations.
+	//
+	// For example, consider a situation in which goroutines block on the GC
+	// (such as via runtime.GOMAXPROCS) and only fractional mark workers are
+	// scheduled (e.g. GOMAXPROCS=1). Without idle-priority mark workers, the
+	// last running M might skip scheduling a fractional mark worker if its
+	// utilization goal is met, such that once it goes to sleep (because there's
+	// nothing to do), there will be nothing else to spin up a new M for the
+	// fractional worker in the future, stalling GC progress and causing a
+	// deadlock. However, idle-priority workers will *always* run when there is
+	// nothing left to do, ensuring the GC makes progress.
+	//
+	// See github.com/golang/go/issues/44163 for more details.
+	idleMarkWorkers atomic.Uint64
+
+	// assistWorkPerByte is the ratio of scan work to allocated
+	// bytes that should be performed by mutator assists. This is
+	// computed at the beginning of each cycle and updated every
+	// time heapScan is updated.
+	assistWorkPerByte atomic.Float64
+
+	// assistBytesPerWork is 1/assistWorkPerByte.
+	//
+	// Note that because this is read and written independently
+	// from assistWorkPerByte users may notice a skew between
+	// the two values, and such a state should be safe.
+	assistBytesPerWork atomic.Float64
+
+	// fractionalUtilizationGoal is the fraction of wall clock
+	// time that should be spent in the fractional mark worker on
+	// each P that isn't running a dedicated worker.
+	//
+	// For example, if the utilization goal is 25% and there are
+	// no dedicated workers, this will be 0.25. If the goal is
+	// 25%, there is one dedicated worker, and GOMAXPROCS is 5,
+	// this will be 0.05 to make up the missing 5%.
+	//
+	// If this is zero, no fractional workers are needed.
+	fractionalUtilizationGoal float64
+
+	// These memory stats are effectively duplicates of fields from
+	// memstats.heapStats but are updated atomically or with the world
+	// stopped and don't provide the same consistency guarantees.
+	//
+	// Because the runtime is responsible for managing a memory limit, it's
+	// useful to couple these stats more tightly to the gcController, which
+	// is intimately connected to how that memory limit is maintained.
+	heapInUse    sysMemStat    // bytes in mSpanInUse spans
+	heapReleased sysMemStat    // bytes released to the OS
+	heapFree     sysMemStat    // bytes not in any span, but not released to the OS
+	totalAlloc   atomic.Uint64 // total bytes allocated
+	totalFree    atomic.Uint64 // total bytes freed
+	mappedReady  atomic.Uint64 // total virtual memory in the Ready state (see mem.go).
+
+	// test indicates that this is a test-only copy of gcControllerState.
+	test bool
+
+	_ cpu.CacheLinePad
+}
+
+func (c *gcControllerState) init(gcPercent int32, memoryLimit int64) {
+	c.heapMinimum = defaultHeapMinimum
+	c.triggered = ^uint64(0)
+
+	c.consMarkController = piController{
+		// Tuned first via the Ziegler-Nichols process in simulation,
+		// then the integral time was manually tuned against real-world
+		// applications to deal with noisiness in the measured cons/mark
+		// ratio.
+		kp: 0.9,
+		ti: 4.0,
+
+		// Set a high reset time in GC cycles.
+		// This is inversely proportional to the rate at which we
+		// accumulate error from clipping. By making this very high
+		// we make the accumulation slow. In general, clipping is
+		// OK in our situation, hence the choice.
+		//
+		// Tune this if we get unintended effects from clipping for
+		// a long time.
+		tt:  1000,
+		min: -1000,
+		max: 1000,
+	}
+
+	c.setGCPercent(gcPercent)
+	c.setMemoryLimit(memoryLimit)
+	c.commit(true) // No sweep phase in the first GC cycle.
+	// N.B. Don't bother calling traceHeapGoal. Tracing is never enabled at
+	// initialization time.
+	// N.B. No need to call revise; there's no GC enabled during
+	// initialization.
+}
+
+// startCycle resets the GC controller's state and computes estimates
+// for a new GC cycle. The caller must hold worldsema and the world
+// must be stopped.
+func (c *gcControllerState) startCycle(markStartTime int64, procs int, trigger gcTrigger) {
+	c.heapScanWork.Store(0)
+	c.stackScanWork.Store(0)
+	c.globalsScanWork.Store(0)
+	c.bgScanCredit = 0
+	c.assistTime.Store(0)
+	c.dedicatedMarkTime = 0
+	c.fractionalMarkTime = 0
+	c.idleMarkTime = 0
+	c.markStartTime = markStartTime
+
+	// TODO(mknyszek): This is supposed to be the actual trigger point for the heap, but
+	// causes regressions in memory use. The cause is that the PI controller used to smooth
+	// the cons/mark ratio measurements tends to flail when using the less accurate precomputed
+	// trigger for the cons/mark calculation, and this results in the controller being more
+	// conservative about steady-states it tries to find in the future.
+	//
+	// This conservatism is transient, but these transient states tend to matter for short-lived
+	// programs, especially because the PI controller is overdamped, partially because it is
+	// configured with a relatively large time constant.
+	//
+	// Ultimately, I think this is just two mistakes piled on one another: the choice of a swingy
+	// smoothing function that recalls a fairly long history (due to its overdamped time constant)
+	// coupled with an inaccurate cons/mark calculation. It just so happens this works better
+	// today, and it makes it harder to change things in the future.
+	//
+	// This is described in #53738. Fix this for #53892 by changing back to the actual trigger
+	// point and simplifying the smoothing function.
+	heapTrigger, heapGoal := c.trigger()
+	c.triggered = heapTrigger
+
+	// Compute the background mark utilization goal. In general,
+	// this may not come out exactly. We round the number of
+	// dedicated workers so that the utilization is closest to
+	// 25%. For small GOMAXPROCS, this would introduce too much
+	// error, so we add fractional workers in that case.
+	totalUtilizationGoal := float64(procs) * gcBackgroundUtilization
+	c.dedicatedMarkWorkersNeeded = int64(totalUtilizationGoal + 0.5)
+	utilError := float64(c.dedicatedMarkWorkersNeeded)/totalUtilizationGoal - 1
+	const maxUtilError = 0.3
+	if utilError < -maxUtilError || utilError > maxUtilError {
+		// Rounding put us more than 30% off our goal. With
+		// gcBackgroundUtilization of 25%, this happens for
+		// GOMAXPROCS<=3 or GOMAXPROCS=6. Enable fractional
+		// workers to compensate.
+		if float64(c.dedicatedMarkWorkersNeeded) > totalUtilizationGoal {
+			// Too many dedicated workers.
+			c.dedicatedMarkWorkersNeeded--
+		}
+		c.fractionalUtilizationGoal = (totalUtilizationGoal - float64(c.dedicatedMarkWorkersNeeded)) / float64(procs)
+	} else {
+		c.fractionalUtilizationGoal = 0
+	}
+
+	// In STW mode, we just want dedicated workers.
+	if debug.gcstoptheworld > 0 {
+		c.dedicatedMarkWorkersNeeded = int64(procs)
+		c.fractionalUtilizationGoal = 0
+	}
+
+	// Clear per-P state
+	for _, p := range allp {
+		p.gcAssistTime = 0
+		p.gcFractionalMarkTime = 0
+	}
+
+	if trigger.kind == gcTriggerTime {
+		// During a periodic GC cycle, reduce the number of idle mark workers
+		// required. However, we need at least one dedicated mark worker or
+		// idle GC worker to ensure GC progress in some scenarios (see comment
+		// on maxIdleMarkWorkers).
+		if c.dedicatedMarkWorkersNeeded > 0 {
+			c.setMaxIdleMarkWorkers(0)
+		} else {
+			// TODO(mknyszek): The fundamental reason why we need this is because
+			// we can't count on the fractional mark worker to get scheduled.
+			// Fix that by ensuring it gets scheduled according to its quota even
+			// if the rest of the application is idle.
+			c.setMaxIdleMarkWorkers(1)
+		}
+	} else {
+		// N.B. gomaxprocs and dedicatedMarkWorkersNeeded is guaranteed not to
+		// change during a GC cycle.
+		c.setMaxIdleMarkWorkers(int32(procs) - int32(c.dedicatedMarkWorkersNeeded))
+	}
+
+	// Compute initial values for controls that are updated
+	// throughout the cycle.
+	c.revise()
+
+	if debug.gcpacertrace > 0 {
+		assistRatio := c.assistWorkPerByte.Load()
+		print("pacer: assist ratio=", assistRatio,
+			" (scan ", gcController.heapScan>>20, " MB in ",
+			work.initialHeapLive>>20, "->",
+			heapGoal>>20, " MB)",
+			" workers=", c.dedicatedMarkWorkersNeeded,
+			"+", c.fractionalUtilizationGoal, "\n")
+	}
+}
+
+// revise updates the assist ratio during the GC cycle to account for
+// improved estimates. This should be called whenever gcController.heapScan,
+// gcController.heapLive, or if any inputs to gcController.heapGoal are
+// updated. It is safe to call concurrently, but it may race with other
+// calls to revise.
+//
+// The result of this race is that the two assist ratio values may not line
+// up or may be stale. In practice this is OK because the assist ratio
+// moves slowly throughout a GC cycle, and the assist ratio is a best-effort
+// heuristic anyway. Furthermore, no part of the heuristic depends on
+// the two assist ratio values being exact reciprocals of one another, since
+// the two values are used to convert values from different sources.
+//
+// The worst case result of this raciness is that we may miss a larger shift
+// in the ratio (say, if we decide to pace more aggressively against the
+// hard heap goal) but even this "hard goal" is best-effort (see #40460).
+// The dedicated GC should ensure we don't exceed the hard goal by too much
+// in the rare case we do exceed it.
+//
+// It should only be called when gcBlackenEnabled != 0 (because this
+// is when assists are enabled and the necessary statistics are
+// available).
+func (c *gcControllerState) revise() {
+	gcPercent := c.gcPercent.Load()
+	if gcPercent < 0 {
+		// If GC is disabled but we're running a forced GC,
+		// act like GOGC is huge for the below calculations.
+		gcPercent = 100000
+	}
+	live := atomic.Load64(&c.heapLive)
+	scan := atomic.Load64(&c.heapScan)
+	work := c.heapScanWork.Load() + c.stackScanWork.Load() + c.globalsScanWork.Load()
+
+	// Assume we're under the soft goal. Pace GC to complete at
+	// heapGoal assuming the heap is in steady-state.
+	heapGoal := int64(c.heapGoal())
+
+	// The expected scan work is computed as the amount of bytes scanned last
+	// GC cycle (both heap and stack), plus our estimate of globals work for this cycle.
+	scanWorkExpected := int64(c.lastHeapScan + c.lastStackScan + c.globalsScan)
+
+	// maxScanWork is a worst-case estimate of the amount of scan work that
+	// needs to be performed in this GC cycle. Specifically, it represents
+	// the case where *all* scannable memory turns out to be live, and
+	// *all* allocated stack space is scannable.
+	maxStackScan := atomic.Load64(&c.maxStackScan)
+	maxScanWork := int64(scan + maxStackScan + c.globalsScan)
+	if work > scanWorkExpected {
+		// We've already done more scan work than expected. Because our expectation
+		// is based on a steady-state scannable heap size, we assume this means our
+		// heap is growing. Compute a new heap goal that takes our existing runway
+		// computed for scanWorkExpected and extrapolates it to maxScanWork, the worst-case
+		// scan work. This keeps our assist ratio stable if the heap continues to grow.
+		//
+		// The effect of this mechanism is that assists stay flat in the face of heap
+		// growths. It's OK to use more memory this cycle to scan all the live heap,
+		// because the next GC cycle is inevitably going to use *at least* that much
+		// memory anyway.
+		extHeapGoal := int64(float64(heapGoal-int64(c.triggered))/float64(scanWorkExpected)*float64(maxScanWork)) + int64(c.triggered)
+		scanWorkExpected = maxScanWork
+
+		// hardGoal is a hard limit on the amount that we're willing to push back the
+		// heap goal, and that's twice the heap goal (i.e. if GOGC=100 and the heap and/or
+		// stacks and/or globals grow to twice their size, this limits the current GC cycle's
+		// growth to 4x the original live heap's size).
+		//
+		// This maintains the invariant that we use no more memory than the next GC cycle
+		// will anyway.
+		hardGoal := int64((1.0 + float64(gcPercent)/100.0) * float64(heapGoal))
+		if extHeapGoal > hardGoal {
+			extHeapGoal = hardGoal
+		}
+		heapGoal = extHeapGoal
+	}
+	if int64(live) > heapGoal {
+		// We're already past our heap goal, even the extrapolated one.
+		// Leave ourselves some extra runway, so in the worst case we
+		// finish by that point.
+		const maxOvershoot = 1.1
+		heapGoal = int64(float64(heapGoal) * maxOvershoot)
+
+		// Compute the upper bound on the scan work remaining.
+		scanWorkExpected = maxScanWork
+	}
+
+	// Compute the remaining scan work estimate.
+	//
+	// Note that we currently count allocations during GC as both
+	// scannable heap (heapScan) and scan work completed
+	// (scanWork), so allocation will change this difference
+	// slowly in the soft regime and not at all in the hard
+	// regime.
+	scanWorkRemaining := scanWorkExpected - work
+	if scanWorkRemaining < 1000 {
+		// We set a somewhat arbitrary lower bound on
+		// remaining scan work since if we aim a little high,
+		// we can miss by a little.
+		//
+		// We *do* need to enforce that this is at least 1,
+		// since marking is racy and double-scanning objects
+		// may legitimately make the remaining scan work
+		// negative, even in the hard goal regime.
+		scanWorkRemaining = 1000
+	}
+
+	// Compute the heap distance remaining.
+	heapRemaining := heapGoal - int64(live)
+	if heapRemaining <= 0 {
+		// This shouldn't happen, but if it does, avoid
+		// dividing by zero or setting the assist negative.
+		heapRemaining = 1
+	}
+
+	// Compute the mutator assist ratio so by the time the mutator
+	// allocates the remaining heap bytes up to heapGoal, it will
+	// have done (or stolen) the remaining amount of scan work.
+	// Note that the assist ratio values are updated atomically
+	// but not together. This means there may be some degree of
+	// skew between the two values. This is generally OK as the
+	// values shift relatively slowly over the course of a GC
+	// cycle.
+	assistWorkPerByte := float64(scanWorkRemaining) / float64(heapRemaining)
+	assistBytesPerWork := float64(heapRemaining) / float64(scanWorkRemaining)
+	c.assistWorkPerByte.Store(assistWorkPerByte)
+	c.assistBytesPerWork.Store(assistBytesPerWork)
+}
+
+// endCycle computes the consMark estimate for the next cycle.
+// userForced indicates whether the current GC cycle was forced
+// by the application.
+func (c *gcControllerState) endCycle(now int64, procs int, userForced bool) {
+	// Record last heap goal for the scavenger.
+	// We'll be updating the heap goal soon.
+	gcController.lastHeapGoal = c.heapGoal()
+
+	// Compute the duration of time for which assists were turned on.
+	assistDuration := now - c.markStartTime
+
+	// Assume background mark hit its utilization goal.
+	utilization := gcBackgroundUtilization
+	// Add assist utilization; avoid divide by zero.
+	if assistDuration > 0 {
+		utilization += float64(c.assistTime.Load()) / float64(assistDuration*int64(procs))
+	}
+
+	if c.heapLive <= c.triggered {
+		// Shouldn't happen, but let's be very safe about this in case the
+		// GC is somehow extremely short.
+		//
+		// In this case though, the only reasonable value for c.heapLive-c.triggered
+		// would be 0, which isn't really all that useful, i.e. the GC was so short
+		// that it didn't matter.
+		//
+		// Ignore this case and don't update anything.
+		return
+	}
+	idleUtilization := 0.0
+	if assistDuration > 0 {
+		idleUtilization = float64(c.idleMarkTime) / float64(assistDuration*int64(procs))
+	}
+	// Determine the cons/mark ratio.
+	//
+	// The units we want for the numerator and denominator are both B / cpu-ns.
+	// We get this by taking the bytes allocated or scanned, and divide by the amount of
+	// CPU time it took for those operations. For allocations, that CPU time is
+	//
+	//    assistDuration * procs * (1 - utilization)
+	//
+	// Where utilization includes just background GC workers and assists. It does *not*
+	// include idle GC work time, because in theory the mutator is free to take that at
+	// any point.
+	//
+	// For scanning, that CPU time is
+	//
+	//    assistDuration * procs * (utilization + idleUtilization)
+	//
+	// In this case, we *include* idle utilization, because that is additional CPU time that the
+	// the GC had available to it.
+	//
+	// In effect, idle GC time is sort of double-counted here, but it's very weird compared
+	// to other kinds of GC work, because of how fluid it is. Namely, because the mutator is
+	// *always* free to take it.
+	//
+	// So this calculation is really:
+	//     (heapLive-trigger) / (assistDuration * procs * (1-utilization)) /
+	//         (scanWork) / (assistDuration * procs * (utilization+idleUtilization)
+	//
+	// Note that because we only care about the ratio, assistDuration and procs cancel out.
+	scanWork := c.heapScanWork.Load() + c.stackScanWork.Load() + c.globalsScanWork.Load()
+	currentConsMark := (float64(c.heapLive-c.triggered) * (utilization + idleUtilization)) /
+		(float64(scanWork) * (1 - utilization))
+
+	// Update cons/mark controller. The time period for this is 1 GC cycle.
+	//
+	// This use of a PI controller might seem strange. So, here's an explanation:
+	//
+	// currentConsMark represents the consMark we *should've* had to be perfectly
+	// on-target for this cycle. Given that we assume the next GC will be like this
+	// one in the steady-state, it stands to reason that we should just pick that
+	// as our next consMark. In practice, however, currentConsMark is too noisy:
+	// we're going to be wildly off-target in each GC cycle if we do that.
+	//
+	// What we do instead is make a long-term assumption: there is some steady-state
+	// consMark value, but it's obscured by noise. By constantly shooting for this
+	// noisy-but-perfect consMark value, the controller will bounce around a bit,
+	// but its average behavior, in aggregate, should be less noisy and closer to
+	// the true long-term consMark value, provided its tuned to be slightly overdamped.
+	var ok bool
+	oldConsMark := c.consMark
+	c.consMark, ok = c.consMarkController.next(c.consMark, currentConsMark, 1.0)
+	if !ok {
+		// The error spiraled out of control. This is incredibly unlikely seeing
+		// as this controller is essentially just a smoothing function, but it might
+		// mean that something went very wrong with how currentConsMark was calculated.
+		// Just reset consMark and keep going.
+		c.consMark = 0
+	}
+
+	if debug.gcpacertrace > 0 {
+		printlock()
+		goal := gcGoalUtilization * 100
+		print("pacer: ", int(utilization*100), "% CPU (", int(goal), " exp.) for ")
+		print(c.heapScanWork.Load(), "+", c.stackScanWork.Load(), "+", c.globalsScanWork.Load(), " B work (", c.lastHeapScan+c.lastStackScan+c.globalsScan, " B exp.) ")
+		print("in ", c.triggered, " B -> ", c.heapLive, " B (∆goal ", int64(c.heapLive)-int64(c.lastHeapGoal), ", cons/mark ", oldConsMark, ")")
+		if !ok {
+			print("[controller reset]")
+		}
+		println()
+		printunlock()
+	}
+}
+
+// enlistWorker encourages another dedicated mark worker to start on
+// another P if there are spare worker slots. It is used by putfull
+// when more work is made available.
+//
+//go:nowritebarrier
+func (c *gcControllerState) enlistWorker() {
+	// If there are idle Ps, wake one so it will run an idle worker.
+	// NOTE: This is suspected of causing deadlocks. See golang.org/issue/19112.
+	//
+	//	if atomic.Load(&sched.npidle) != 0 && atomic.Load(&sched.nmspinning) == 0 {
+	//		wakep()
+	//		return
+	//	}
+
+	// There are no idle Ps. If we need more dedicated workers,
+	// try to preempt a running P so it will switch to a worker.
+	if c.dedicatedMarkWorkersNeeded <= 0 {
+		return
+	}
+	// Pick a random other P to preempt.
+	if gomaxprocs <= 1 {
+		return
+	}
+	gp := getg()
+	if gp == nil || gp.m == nil || gp.m.p == 0 {
+		return
+	}
+	myID := gp.m.p.ptr().id
+	for tries := 0; tries < 5; tries++ {
+		id := int32(fastrandn(uint32(gomaxprocs - 1)))
+		if id >= myID {
+			id++
+		}
+		p := allp[id]
+		if p.status != _Prunning {
+			continue
+		}
+		if preemptone(p) {
+			return
+		}
+	}
+}
+
+// findRunnableGCWorker returns a background mark worker for _p_ if it
+// should be run. This must only be called when gcBlackenEnabled != 0.
+func (c *gcControllerState) findRunnableGCWorker(_p_ *p, now int64) (*g, int64) {
+	if gcBlackenEnabled == 0 {
+		throw("gcControllerState.findRunnable: blackening not enabled")
+	}
+
+	// Since we have the current time, check if the GC CPU limiter
+	// hasn't had an update in a while. This check is necessary in
+	// case the limiter is on but hasn't been checked in a while and
+	// so may have left sufficient headroom to turn off again.
+	if now == 0 {
+		now = nanotime()
+	}
+	if gcCPULimiter.needUpdate(now) {
+		gcCPULimiter.update(now)
+	}
+
+	if !gcMarkWorkAvailable(_p_) {
+		// No work to be done right now. This can happen at
+		// the end of the mark phase when there are still
+		// assists tapering off. Don't bother running a worker
+		// now because it'll just return immediately.
+		return nil, now
+	}
+
+	// Grab a worker before we commit to running below.
+	node := (*gcBgMarkWorkerNode)(gcBgMarkWorkerPool.pop())
+	if node == nil {
+		// There is at least one worker per P, so normally there are
+		// enough workers to run on all Ps, if necessary. However, once
+		// a worker enters gcMarkDone it may park without rejoining the
+		// pool, thus freeing a P with no corresponding worker.
+		// gcMarkDone never depends on another worker doing work, so it
+		// is safe to simply do nothing here.
+		//
+		// If gcMarkDone bails out without completing the mark phase,
+		// it will always do so with queued global work. Thus, that P
+		// will be immediately eligible to re-run the worker G it was
+		// just using, ensuring work can complete.
+		return nil, now
+	}
+
+	decIfPositive := func(ptr *int64) bool {
+		for {
+			v := atomic.Loadint64(ptr)
+			if v <= 0 {
+				return false
+			}
+
+			if atomic.Casint64(ptr, v, v-1) {
+				return true
+			}
+		}
+	}
+
+	if decIfPositive(&c.dedicatedMarkWorkersNeeded) {
+		// This P is now dedicated to marking until the end of
+		// the concurrent mark phase.
+		_p_.gcMarkWorkerMode = gcMarkWorkerDedicatedMode
+	} else if c.fractionalUtilizationGoal == 0 {
+		// No need for fractional workers.
+		gcBgMarkWorkerPool.push(&node.node)
+		return nil, now
+	} else {
+		// Is this P behind on the fractional utilization
+		// goal?
+		//
+		// This should be kept in sync with pollFractionalWorkerExit.
+		delta := now - c.markStartTime
+		if delta > 0 && float64(_p_.gcFractionalMarkTime)/float64(delta) > c.fractionalUtilizationGoal {
+			// Nope. No need to run a fractional worker.
+			gcBgMarkWorkerPool.push(&node.node)
+			return nil, now
+		}
+		// Run a fractional worker.
+		_p_.gcMarkWorkerMode = gcMarkWorkerFractionalMode
+	}
+
+	// Run the background mark worker.
+	gp := node.gp.ptr()
+	casgstatus(gp, _Gwaiting, _Grunnable)
+	if trace.enabled {
+		traceGoUnpark(gp, 0)
+	}
+	return gp, now
+}
+
+// resetLive sets up the controller state for the next mark phase after the end
+// of the previous one. Must be called after endCycle and before commit, before
+// the world is started.
+//
+// The world must be stopped.
+func (c *gcControllerState) resetLive(bytesMarked uint64) {
+	c.heapMarked = bytesMarked
+	c.heapLive = bytesMarked
+	c.heapScan = uint64(c.heapScanWork.Load())
+	c.lastHeapScan = uint64(c.heapScanWork.Load())
+	c.lastStackScan = uint64(c.stackScanWork.Load())
+	c.triggered = ^uint64(0) // Reset triggered.
+
+	// heapLive was updated, so emit a trace event.
+	if trace.enabled {
+		traceHeapAlloc()
+	}
+}
+
+// markWorkerStop must be called whenever a mark worker stops executing.
+//
+// It updates mark work accounting in the controller by a duration of
+// work in nanoseconds and other bookkeeping.
+//
+// Safe to execute at any time.
+func (c *gcControllerState) markWorkerStop(mode gcMarkWorkerMode, duration int64) {
+	switch mode {
+	case gcMarkWorkerDedicatedMode:
+		atomic.Xaddint64(&c.dedicatedMarkTime, duration)
+		atomic.Xaddint64(&c.dedicatedMarkWorkersNeeded, 1)
+	case gcMarkWorkerFractionalMode:
+		atomic.Xaddint64(&c.fractionalMarkTime, duration)
+	case gcMarkWorkerIdleMode:
+		atomic.Xaddint64(&c.idleMarkTime, duration)
+		c.removeIdleMarkWorker()
+	default:
+		throw("markWorkerStop: unknown mark worker mode")
+	}
+}
+
+func (c *gcControllerState) update(dHeapLive, dHeapScan int64) {
+	if dHeapLive != 0 {
+		atomic.Xadd64(&gcController.heapLive, dHeapLive)
+		if trace.enabled {
+			// gcController.heapLive changed.
+			traceHeapAlloc()
+		}
+	}
+	if gcBlackenEnabled == 0 {
+		// Update heapScan when we're not in a current GC. It is fixed
+		// at the beginning of a cycle.
+		if dHeapScan != 0 {
+			atomic.Xadd64(&gcController.heapScan, dHeapScan)
+		}
+	} else {
+		// gcController.heapLive changed.
+		c.revise()
+	}
+}
+
+func (c *gcControllerState) addScannableStack(pp *p, amount int64) {
+	if pp == nil {
+		atomic.Xadd64(&c.maxStackScan, amount)
+		return
+	}
+	pp.maxStackScanDelta += amount
+	if pp.maxStackScanDelta >= maxStackScanSlack || pp.maxStackScanDelta <= -maxStackScanSlack {
+		atomic.Xadd64(&c.maxStackScan, pp.maxStackScanDelta)
+		pp.maxStackScanDelta = 0
+	}
+}
+
+func (c *gcControllerState) addGlobals(amount int64) {
+	atomic.Xadd64(&c.globalsScan, amount)
+}
+
+// heapGoal returns the current heap goal.
+func (c *gcControllerState) heapGoal() uint64 {
+	goal, _ := c.heapGoalInternal()
+	return goal
+}
+
+// heapGoalInternal is the implementation of heapGoal which returns additional
+// information that is necessary for computing the trigger.
+//
+// The returned minTrigger is always <= goal.
+func (c *gcControllerState) heapGoalInternal() (goal, minTrigger uint64) {
+	// Start with the goal calculated for gcPercent.
+	goal = c.gcPercentHeapGoal.Load()
+
+	// Check if the memory-limit-based goal is smaller, and if so, pick that.
+	if newGoal := c.memoryLimitHeapGoal(); go119MemoryLimitSupport && newGoal < goal {
+		goal = newGoal
+	} else {
+		// We're not limited by the memory limit goal, so perform a series of
+		// adjustments that might move the goal forward in a variety of circumstances.
+
+		sweepDistTrigger := c.sweepDistMinTrigger.Load()
+		if sweepDistTrigger > goal {
+			// Set the goal to maintain a minimum sweep distance since
+			// the last call to commit. Note that we never want to do this
+			// if we're in the memory limit regime, because it could push
+			// the goal up.
+			goal = sweepDistTrigger
+		}
+		// Since we ignore the sweep distance trigger in the memory
+		// limit regime, we need to ensure we don't propagate it to
+		// the trigger, because it could cause a violation of the
+		// invariant that the trigger < goal.
+		minTrigger = sweepDistTrigger
+
+		// Ensure that the heap goal is at least a little larger than
+		// the point at which we triggered. This may not be the case if GC
+		// start is delayed or if the allocation that pushed gcController.heapLive
+		// over trigger is large or if the trigger is really close to
+		// GOGC. Assist is proportional to this distance, so enforce a
+		// minimum distance, even if it means going over the GOGC goal
+		// by a tiny bit.
+		//
+		// Ignore this if we're in the memory limit regime: we'd prefer to
+		// have the GC respond hard about how close we are to the goal than to
+		// push the goal back in such a manner that it could cause us to exceed
+		// the memory limit.
+		const minRunway = 64 << 10
+		if c.triggered != ^uint64(0) && goal < c.triggered+minRunway {
+			goal = c.triggered + minRunway
+		}
+	}
+	return
+}
+
+// memoryLimitHeapGoal returns a heap goal derived from memoryLimit.
+func (c *gcControllerState) memoryLimitHeapGoal() uint64 {
+	// Start by pulling out some values we'll need. Be careful about overflow.
+	var heapFree, heapAlloc, mappedReady uint64
+	for {
+		heapFree = c.heapFree.load()                         // Free and unscavenged memory.
+		heapAlloc = c.totalAlloc.Load() - c.totalFree.Load() // Heap object bytes in use.
+		mappedReady = c.mappedReady.Load()                   // Total unreleased mapped memory.
+		if heapFree+heapAlloc <= mappedReady {
+			break
+		}
+		// It is impossible for total unreleased mapped memory to exceed heap memory, but
+		// because these stats are updated independently, we may observe a partial update
+		// including only some values. Thus, we appear to break the invariant. However,
+		// this condition is necessarily transient, so just try again. In the case of a
+		// persistent accounting error, we'll deadlock here.
+	}
+
+	// Below we compute a goal from memoryLimit. There are a few things to be aware of.
+	// Firstly, the memoryLimit does not easily compare to the heap goal: the former
+	// is total mapped memory by the runtime that hasn't been released, while the latter is
+	// only heap object memory. Intuitively, the way we convert from one to the other is to
+	// subtract everything from memoryLimit that both contributes to the memory limit (so,
+	// ignore scavenged memory) and doesn't contain heap objects. This isn't quite what
+	// lines up with reality, but it's a good starting point.
+	//
+	// In practice this computation looks like the following:
+	//
+	//    memoryLimit - ((mappedReady - heapFree - heapAlloc) + max(mappedReady - memoryLimit, 0)) - memoryLimitHeapGoalHeadroom
+	//                    ^1                                    ^2                                   ^3
+	//
+	// Let's break this down.
+	//
+	// The first term (marker 1) is everything that contributes to the memory limit and isn't
+	// or couldn't become heap objects. It represents, broadly speaking, non-heap overheads.
+	// One oddity you may have noticed is that we also subtract out heapFree, i.e. unscavenged
+	// memory that may contain heap objects in the future.
+	//
+	// Let's take a step back. In an ideal world, this term would look something like just
+	// the heap goal. That is, we "reserve" enough space for the heap to grow to the heap
+	// goal, and subtract out everything else. This is of course impossible; the definition
+	// is circular! However, this impossible definition contains a key insight: the amount
+	// we're *going* to use matters just as much as whatever we're currently using.
+	//
+	// Consider if the heap shrinks to 1/10th its size, leaving behind lots of free and
+	// unscavenged memory. mappedReady - heapAlloc will be quite large, because of that free
+	// and unscavenged memory, pushing the goal down significantly.
+	//
+	// heapFree is also safe to exclude from the memory limit because in the steady-state, it's
+	// just a pool of memory for future heap allocations, and making new allocations from heapFree
+	// memory doesn't increase overall memory use. In transient states, the scavenger and the
+	// allocator actively manage the pool of heapFree memory to maintain the memory limit.
+	//
+	// The second term (marker 2) is the amount of memory we've exceeded the limit by, and is
+	// intended to help recover from such a situation. By pushing the heap goal down, we also
+	// push the trigger down, triggering and finishing a GC sooner in order to make room for
+	// other memory sources. Note that since we're effectively reducing the heap goal by X bytes,
+	// we're actually giving more than X bytes of headroom back, because the heap goal is in
+	// terms of heap objects, but it takes more than X bytes (e.g. due to fragmentation) to store
+	// X bytes worth of objects.
+	//
+	// The third term (marker 3) subtracts an additional memoryLimitHeapGoalHeadroom bytes from the
+	// heap goal. As the name implies, this is to provide additional headroom in the face of pacing
+	// inaccuracies. This is a fixed number of bytes because these inaccuracies disproportionately
+	// affect small heaps: as heaps get smaller, the pacer's inputs get fuzzier. Shorter GC cycles
+	// and less GC work means noisy external factors like the OS scheduler have a greater impact.
+
+	memoryLimit := uint64(c.memoryLimit.Load())
+
+	// Compute term 1.
+	nonHeapMemory := mappedReady - heapFree - heapAlloc
+
+	// Compute term 2.
+	var overage uint64
+	if mappedReady > memoryLimit {
+		overage = mappedReady - memoryLimit
+	}
+
+	if nonHeapMemory+overage >= memoryLimit {
+		// We're at a point where non-heap memory exceeds the memory limit on its own.
+		// There's honestly not much we can do here but just trigger GCs continuously
+		// and let the CPU limiter reign that in. Something has to give at this point.
+		// Set it to heapMarked, the lowest possible goal.
+		return c.heapMarked
+	}
+
+	// Compute the goal.
+	goal := memoryLimit - (nonHeapMemory + overage)
+
+	// Apply some headroom to the goal to account for pacing inaccuracies.
+	// Be careful about small limits.
+	if goal < memoryLimitHeapGoalHeadroom || goal-memoryLimitHeapGoalHeadroom < memoryLimitHeapGoalHeadroom {
+		goal = memoryLimitHeapGoalHeadroom
+	} else {
+		goal = goal - memoryLimitHeapGoalHeadroom
+	}
+	// Don't let us go below the live heap. A heap goal below the live heap doesn't make sense.
+	if goal < c.heapMarked {
+		goal = c.heapMarked
+	}
+	return goal
+}
+
+const (
+	// These constants determine the bounds on the GC trigger as a fraction
+	// of heap bytes allocated between the start of a GC (heapLive == heapMarked)
+	// and the end of a GC (heapLive == heapGoal).
+	//
+	// The constants are obscured in this way for efficiency. The denominator
+	// of the fraction is always a power-of-two for a quick division, so that
+	// the numerator is a single constant integer multiplication.
+	triggerRatioDen = 64
+
+	// The minimum trigger constant was chosen empirically: given a sufficiently
+	// fast/scalable allocator with 48 Ps that could drive the trigger ratio
+	// to <0.05, this constant causes applications to retain the same peak
+	// RSS compared to not having this allocator.
+	minTriggerRatioNum = 45 // ~0.7
+
+	// The maximum trigger constant is chosen somewhat arbitrarily, but the
+	// current constant has served us well over the years.
+	maxTriggerRatioNum = 61 // ~0.95
+)
+
+// trigger returns the current point at which a GC should trigger along with
+// the heap goal.
+//
+// The returned value may be compared against heapLive to determine whether
+// the GC should trigger. Thus, the GC trigger condition should be (but may
+// not be, in the case of small movements for efficiency) checked whenever
+// the heap goal may change.
+func (c *gcControllerState) trigger() (uint64, uint64) {
+	goal, minTrigger := c.heapGoalInternal()
+
+	// Invariant: the trigger must always be less than the heap goal.
+	//
+	// Note that the memory limit sets a hard maximum on our heap goal,
+	// but the live heap may grow beyond it.
+
+	if c.heapMarked >= goal {
+		// The goal should never be smaller than heapMarked, but let's be
+		// defensive about it. The only reasonable trigger here is one that
+		// causes a continuous GC cycle at heapMarked, but respect the goal
+		// if it came out as smaller than that.
+		return goal, goal
+	}
+
+	// Below this point, c.heapMarked < goal.
+
+	// heapMarked is our absolute minimum, and it's possible the trigger
+	// bound we get from heapGoalinternal is less than that.
+	if minTrigger < c.heapMarked {
+		minTrigger = c.heapMarked
+	}
+
+	// If we let the trigger go too low, then if the application
+	// is allocating very rapidly we might end up in a situation
+	// where we're allocating black during a nearly always-on GC.
+	// The result of this is a growing heap and ultimately an
+	// increase in RSS. By capping us at a point >0, we're essentially
+	// saying that we're OK using more CPU during the GC to prevent
+	// this growth in RSS.
+	triggerLowerBound := uint64(((goal-c.heapMarked)/triggerRatioDen)*minTriggerRatioNum) + c.heapMarked
+	if minTrigger < triggerLowerBound {
+		minTrigger = triggerLowerBound
+	}
+
+	// For small heaps, set the max trigger point at maxTriggerRatio of the way
+	// from the live heap to the heap goal. This ensures we always have *some*
+	// headroom when the GC actually starts. For larger heaps, set the max trigger
+	// point at the goal, minus the minimum heap size.
+	//
+	// This choice follows from the fact that the minimum heap size is chosen
+	// to reflect the costs of a GC with no work to do. With a large heap but
+	// very little scan work to perform, this gives us exactly as much runway
+	// as we would need, in the worst case.
+	maxTrigger := uint64(((goal-c.heapMarked)/triggerRatioDen)*maxTriggerRatioNum) + c.heapMarked
+	if goal > defaultHeapMinimum && goal-defaultHeapMinimum > maxTrigger {
+		maxTrigger = goal - defaultHeapMinimum
+	}
+	if maxTrigger < minTrigger {
+		maxTrigger = minTrigger
+	}
+
+	// Compute the trigger from our bounds and the runway stored by commit.
+	var trigger uint64
+	runway := c.runway.Load()
+	if runway > goal {
+		trigger = minTrigger
+	} else {
+		trigger = goal - runway
+	}
+	if trigger < minTrigger {
+		trigger = minTrigger
+	}
+	if trigger > maxTrigger {
+		trigger = maxTrigger
+	}
+	if trigger > goal {
+		print("trigger=", trigger, " heapGoal=", goal, "\n")
+		print("minTrigger=", minTrigger, " maxTrigger=", maxTrigger, "\n")
+		throw("produced a trigger greater than the heap goal")
+	}
+	return trigger, goal
+}
+
+// commit recomputes all pacing parameters needed to derive the
+// trigger and the heap goal. Namely, the gcPercent-based heap goal,
+// and the amount of runway we want to give the GC this cycle.
+//
+// This can be called any time. If GC is the in the middle of a
+// concurrent phase, it will adjust the pacing of that phase.
+//
+// isSweepDone should be the result of calling isSweepDone(),
+// unless we're testing or we know we're executing during a GC cycle.
+//
+// This depends on gcPercent, gcController.heapMarked, and
+// gcController.heapLive. These must be up to date.
+//
+// Callers must call gcControllerState.revise after calling this
+// function if the GC is enabled.
+//
+// mheap_.lock must be held or the world must be stopped.
+func (c *gcControllerState) commit(isSweepDone bool) {
+	if !c.test {
+		assertWorldStoppedOrLockHeld(&mheap_.lock)
+	}
+
+	if isSweepDone {
+		// The sweep is done, so there aren't any restrictions on the trigger
+		// we need to think about.
+		c.sweepDistMinTrigger.Store(0)
+	} else {
+		// Concurrent sweep happens in the heap growth
+		// from gcController.heapLive to trigger. Make sure we
+		// give the sweeper some runway if it doesn't have enough.
+		c.sweepDistMinTrigger.Store(atomic.Load64(&c.heapLive) + sweepMinHeapDistance)
+	}
+
+	// Compute the next GC goal, which is when the allocated heap
+	// has grown by GOGC/100 over where it started the last cycle,
+	// plus additional runway for non-heap sources of GC work.
+	gcPercentHeapGoal := ^uint64(0)
+	if gcPercent := c.gcPercent.Load(); gcPercent >= 0 {
+		gcPercentHeapGoal = c.heapMarked + (c.heapMarked+atomic.Load64(&c.lastStackScan)+atomic.Load64(&c.globalsScan))*uint64(gcPercent)/100
+	}
+	// Apply the minimum heap size here. It's defined in terms of gcPercent
+	// and is only updated by functions that call commit.
+	if gcPercentHeapGoal < c.heapMinimum {
+		gcPercentHeapGoal = c.heapMinimum
+	}
+	c.gcPercentHeapGoal.Store(gcPercentHeapGoal)
+
+	// Compute the amount of runway we want the GC to have by using our
+	// estimate of the cons/mark ratio.
+	//
+	// The idea is to take our expected scan work, and multiply it by
+	// the cons/mark ratio to determine how long it'll take to complete
+	// that scan work in terms of bytes allocated. This gives us our GC's
+	// runway.
+	//
+	// However, the cons/mark ratio is a ratio of rates per CPU-second, but
+	// here we care about the relative rates for some division of CPU
+	// resources among the mutator and the GC.
+	//
+	// To summarize, we have B / cpu-ns, and we want B / ns. We get that
+	// by multiplying by our desired division of CPU resources. We choose
+	// to express CPU resources as GOMAPROCS*fraction. Note that because
+	// we're working with a ratio here, we can omit the number of CPU cores,
+	// because they'll appear in the numerator and denominator and cancel out.
+	// As a result, this is basically just "weighing" the cons/mark ratio by
+	// our desired division of resources.
+	//
+	// Furthermore, by setting the runway so that CPU resources are divided
+	// this way, assuming that the cons/mark ratio is correct, we make that
+	// division a reality.
+	c.runway.Store(uint64((c.consMark * (1 - gcGoalUtilization) / (gcGoalUtilization)) * float64(c.lastHeapScan+c.lastStackScan+c.globalsScan)))
+}
+
+// setGCPercent updates gcPercent. commit must be called after.
+// Returns the old value of gcPercent.
+//
+// The world must be stopped, or mheap_.lock must be held.
+func (c *gcControllerState) setGCPercent(in int32) int32 {
+	if !c.test {
+		assertWorldStoppedOrLockHeld(&mheap_.lock)
+	}
+
+	out := c.gcPercent.Load()
+	if in < 0 {
+		in = -1
+	}
+	c.heapMinimum = defaultHeapMinimum * uint64(in) / 100
+	c.gcPercent.Store(in)
+
+	return out
+}
+
+//go:linkname setGCPercent runtime/debug.setGCPercent
+func setGCPercent(in int32) (out int32) {
+	// Run on the system stack since we grab the heap lock.
+	systemstack(func() {
+		lock(&mheap_.lock)
+		out = gcController.setGCPercent(in)
+		gcControllerCommit()
+		unlock(&mheap_.lock)
+	})
+
+	// If we just disabled GC, wait for any concurrent GC mark to
+	// finish so we always return with no GC running.
+	if in < 0 {
+		gcWaitOnMark(atomic.Load(&work.cycles))
+	}
+
+	return out
+}
+
+func readGOGC() int32 {
+	p := gogetenv("GOGC")
+	if p == "off" {
+		return -1
+	}
+	if n, ok := atoi32(p); ok {
+		return n
+	}
+	return 100
+}
+
+// setMemoryLimit updates memoryLimit. commit must be called after
+// Returns the old value of memoryLimit.
+//
+// The world must be stopped, or mheap_.lock must be held.
+func (c *gcControllerState) setMemoryLimit(in int64) int64 {
+	if !c.test {
+		assertWorldStoppedOrLockHeld(&mheap_.lock)
+	}
+
+	out := c.memoryLimit.Load()
+	if in >= 0 {
+		c.memoryLimit.Store(in)
+	}
+
+	return out
+}
+
+//go:linkname setMemoryLimit runtime/debug.setMemoryLimit
+func setMemoryLimit(in int64) (out int64) {
+	// Run on the system stack since we grab the heap lock.
+	systemstack(func() {
+		lock(&mheap_.lock)
+		out = gcController.setMemoryLimit(in)
+		if in < 0 || out == in {
+			// If we're just checking the value or not changing
+			// it, there's no point in doing the rest.
+			unlock(&mheap_.lock)
+			return
+		}
+		gcControllerCommit()
+		unlock(&mheap_.lock)
+	})
+	return out
+}
+
+func readGOMEMLIMIT() int64 {
+	p := gogetenv("GOMEMLIMIT")
+	if p == "" || p == "off" {
+		return maxInt64
+	}
+	n, ok := parseByteCount(p)
+	if !ok {
+		print("GOMEMLIMIT=", p, "\n")
+		throw("malformed GOMEMLIMIT; see `go doc runtime/debug.SetMemoryLimit`")
+	}
+	return n
+}
+
+type piController struct {
+	kp float64 // Proportional constant.
+	ti float64 // Integral time constant.
+	tt float64 // Reset time.
+
+	min, max float64 // Output boundaries.
+
+	// PI controller state.
+
+	errIntegral float64 // Integral of the error from t=0 to now.
+
+	// Error flags.
+	errOverflow   bool // Set if errIntegral ever overflowed.
+	inputOverflow bool // Set if an operation with the input overflowed.
+}
+
+// next provides a new sample to the controller.
+//
+// input is the sample, setpoint is the desired point, and period is how much
+// time (in whatever unit makes the most sense) has passed since the last sample.
+//
+// Returns a new value for the variable it's controlling, and whether the operation
+// completed successfully. One reason this might fail is if error has been growing
+// in an unbounded manner, to the point of overflow.
+//
+// In the specific case of an error overflow occurs, the errOverflow field will be
+// set and the rest of the controller's internal state will be fully reset.
+func (c *piController) next(input, setpoint, period float64) (float64, bool) {
+	// Compute the raw output value.
+	prop := c.kp * (setpoint - input)
+	rawOutput := prop + c.errIntegral
+
+	// Clamp rawOutput into output.
+	output := rawOutput
+	if isInf(output) || isNaN(output) {
+		// The input had a large enough magnitude that either it was already
+		// overflowed, or some operation with it overflowed.
+		// Set a flag and reset. That's the safest thing to do.
+		c.reset()
+		c.inputOverflow = true
+		return c.min, false
+	}
+	if output < c.min {
+		output = c.min
+	} else if output > c.max {
+		output = c.max
+	}
+
+	// Update the controller's state.
+	if c.ti != 0 && c.tt != 0 {
+		c.errIntegral += (c.kp*period/c.ti)*(setpoint-input) + (period/c.tt)*(output-rawOutput)
+		if isInf(c.errIntegral) || isNaN(c.errIntegral) {
+			// So much error has accumulated that we managed to overflow.
+			// The assumptions around the controller have likely broken down.
+			// Set a flag and reset. That's the safest thing to do.
+			c.reset()
+			c.errOverflow = true
+			return c.min, false
+		}
+	}
+	return output, true
+}
+
+// reset resets the controller state, except for controller error flags.
+func (c *piController) reset() {
+	c.errIntegral = 0
+}
+
+// addIdleMarkWorker attempts to add a new idle mark worker.
+//
+// If this returns true, the caller must become an idle mark worker unless
+// there's no background mark worker goroutines in the pool. This case is
+// harmless because there are already background mark workers running.
+// If this returns false, the caller must NOT become an idle mark worker.
+//
+// nosplit because it may be called without a P.
+//
+//go:nosplit
+func (c *gcControllerState) addIdleMarkWorker() bool {
+	for {
+		old := c.idleMarkWorkers.Load()
+		n, max := int32(old&uint64(^uint32(0))), int32(old>>32)
+		if n >= max {
+			// See the comment on idleMarkWorkers for why
+			// n > max is tolerated.
+			return false
+		}
+		if n < 0 {
+			print("n=", n, " max=", max, "\n")
+			throw("negative idle mark workers")
+		}
+		new := uint64(uint32(n+1)) | (uint64(max) << 32)
+		if c.idleMarkWorkers.CompareAndSwap(old, new) {
+			return true
+		}
+	}
+}
+
+// needIdleMarkWorker is a hint as to whether another idle mark worker is needed.
+//
+// The caller must still call addIdleMarkWorker to become one. This is mainly
+// useful for a quick check before an expensive operation.
+//
+// nosplit because it may be called without a P.
+//
+//go:nosplit
+func (c *gcControllerState) needIdleMarkWorker() bool {
+	p := c.idleMarkWorkers.Load()
+	n, max := int32(p&uint64(^uint32(0))), int32(p>>32)
+	return n < max
+}
+
+// removeIdleMarkWorker must be called when an new idle mark worker stops executing.
+func (c *gcControllerState) removeIdleMarkWorker() {
+	for {
+		old := c.idleMarkWorkers.Load()
+		n, max := int32(old&uint64(^uint32(0))), int32(old>>32)
+		if n-1 < 0 {
+			print("n=", n, " max=", max, "\n")
+			throw("negative idle mark workers")
+		}
+		new := uint64(uint32(n-1)) | (uint64(max) << 32)
+		if c.idleMarkWorkers.CompareAndSwap(old, new) {
+			return
+		}
+	}
+}
+
+// setMaxIdleMarkWorkers sets the maximum number of idle mark workers allowed.
+//
+// This method is optimistic in that it does not wait for the number of
+// idle mark workers to reduce to max before returning; it assumes the workers
+// will deschedule themselves.
+func (c *gcControllerState) setMaxIdleMarkWorkers(max int32) {
+	for {
+		old := c.idleMarkWorkers.Load()
+		n := int32(old & uint64(^uint32(0)))
+		if n < 0 {
+			print("n=", n, " max=", max, "\n")
+			throw("negative idle mark workers")
+		}
+		new := uint64(uint32(n)) | (uint64(max) << 32)
+		if c.idleMarkWorkers.CompareAndSwap(old, new) {
+			return
+		}
+	}
+}
+
+// gcControllerCommit is gcController.commit, but passes arguments from live
+// (non-test) data. It also updates any consumers of the GC pacing, such as
+// sweep pacing and the background scavenger.
+//
+// Calls gcController.commit.
+//
+// The heap lock must be held, so this must be executed on the system stack.
+//
+//go:systemstack
+func gcControllerCommit() {
+	assertWorldStoppedOrLockHeld(&mheap_.lock)
+
+	gcController.commit(isSweepDone())
+
+	// Update mark pacing.
+	if gcphase != _GCoff {
+		gcController.revise()
+	}
+
+	// TODO(mknyszek): This isn't really accurate any longer because the heap
+	// goal is computed dynamically. Still useful to snapshot, but not as useful.
+	if trace.enabled {
+		traceHeapGoal()
+	}
+
+	trigger, heapGoal := gcController.trigger()
+	gcPaceSweeper(trigger)
+	gcPaceScavenger(gcController.memoryLimit.Load(), heapGoal, gcController.lastHeapGoal)
+}
diff --git a/contrib/go/_std_1.19/src/runtime/mgcscavenge.go b/contrib/go/_std_1.19/src/runtime/mgcscavenge.go
new file mode 100644
index 0000000000..bf38f87c77
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/mgcscavenge.go
@@ -0,0 +1,1105 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Scavenging free pages.
+//
+// This file implements scavenging (the release of physical pages backing mapped
+// memory) of free and unused pages in the heap as a way to deal with page-level
+// fragmentation and reduce the RSS of Go applications.
+//
+// Scavenging in Go happens on two fronts: there's the background
+// (asynchronous) scavenger and the heap-growth (synchronous) scavenger.
+//
+// The former happens on a goroutine much like the background sweeper which is
+// soft-capped at using scavengePercent of the mutator's time, based on
+// order-of-magnitude estimates of the costs of scavenging. The background
+// scavenger's primary goal is to bring the estimated heap RSS of the
+// application down to a goal.
+//
+// Before we consider what this looks like, we need to split the world into two
+// halves. One in which a memory limit is not set, and one in which it is.
+//
+// For the former, the goal is defined as:
+//   (retainExtraPercent+100) / 100 * (heapGoal / lastHeapGoal) * lastHeapInUse
+//
+// Essentially, we wish to have the application's RSS track the heap goal, but
+// the heap goal is defined in terms of bytes of objects, rather than pages like
+// RSS. As a result, we need to take into account for fragmentation internal to
+// spans. heapGoal / lastHeapGoal defines the ratio between the current heap goal
+// and the last heap goal, which tells us by how much the heap is growing and
+// shrinking. We estimate what the heap will grow to in terms of pages by taking
+// this ratio and multiplying it by heapInUse at the end of the last GC, which
+// allows us to account for this additional fragmentation. Note that this
+// procedure makes the assumption that the degree of fragmentation won't change
+// dramatically over the next GC cycle. Overestimating the amount of
+// fragmentation simply results in higher memory use, which will be accounted
+// for by the next pacing up date. Underestimating the fragmentation however
+// could lead to performance degradation. Handling this case is not within the
+// scope of the scavenger. Situations where the amount of fragmentation balloons
+// over the course of a single GC cycle should be considered pathologies,
+// flagged as bugs, and fixed appropriately.
+//
+// An additional factor of retainExtraPercent is added as a buffer to help ensure
+// that there's more unscavenged memory to allocate out of, since each allocation
+// out of scavenged memory incurs a potentially expensive page fault.
+//
+// If a memory limit is set, then we wish to pick a scavenge goal that maintains
+// that memory limit. For that, we look at total memory that has been committed
+// (memstats.mappedReady) and try to bring that down below the limit. In this case,
+// we want to give buffer space in the *opposite* direction. When the application
+// is close to the limit, we want to make sure we push harder to keep it under, so
+// if we target below the memory limit, we ensure that the background scavenger is
+// giving the situation the urgency it deserves.
+//
+// In this case, the goal is defined as:
+//    (100-reduceExtraPercent) / 100 * memoryLimit
+//
+// We compute both of these goals, and check whether either of them have been met.
+// The background scavenger continues operating as long as either one of the goals
+// has not been met.
+//
+// The goals are updated after each GC.
+//
+// The synchronous heap-growth scavenging happens whenever the heap grows in
+// size, for some definition of heap-growth. The intuition behind this is that
+// the application had to grow the heap because existing fragments were
+// not sufficiently large to satisfy a page-level memory allocation, so we
+// scavenge those fragments eagerly to offset the growth in RSS that results.
+
+package runtime
+
+import (
+	"internal/goos"
+	"runtime/internal/atomic"
+	"runtime/internal/sys"
+	"unsafe"
+)
+
+const (
+	// The background scavenger is paced according to these parameters.
+	//
+	// scavengePercent represents the portion of mutator time we're willing
+	// to spend on scavenging in percent.
+	scavengePercent = 1 // 1%
+
+	// retainExtraPercent represents the amount of memory over the heap goal
+	// that the scavenger should keep as a buffer space for the allocator.
+	// This constant is used when we do not have a memory limit set.
+	//
+	// The purpose of maintaining this overhead is to have a greater pool of
+	// unscavenged memory available for allocation (since using scavenged memory
+	// incurs an additional cost), to account for heap fragmentation and
+	// the ever-changing layout of the heap.
+	retainExtraPercent = 10
+
+	// reduceExtraPercent represents the amount of memory under the limit
+	// that the scavenger should target. For example, 5 means we target 95%
+	// of the limit.
+	//
+	// The purpose of shooting lower than the limit is to ensure that, once
+	// close to the limit, the scavenger is working hard to maintain it. If
+	// we have a memory limit set but are far away from it, there's no harm
+	// in leaving up to 100-retainExtraPercent live, and it's more efficient
+	// anyway, for the same reasons that retainExtraPercent exists.
+	reduceExtraPercent = 5
+
+	// maxPagesPerPhysPage is the maximum number of supported runtime pages per
+	// physical page, based on maxPhysPageSize.
+	maxPagesPerPhysPage = maxPhysPageSize / pageSize
+
+	// scavengeCostRatio is the approximate ratio between the costs of using previously
+	// scavenged memory and scavenging memory.
+	//
+	// For most systems the cost of scavenging greatly outweighs the costs
+	// associated with using scavenged memory, making this constant 0. On other systems
+	// (especially ones where "sysUsed" is not just a no-op) this cost is non-trivial.
+	//
+	// This ratio is used as part of multiplicative factor to help the scavenger account
+	// for the additional costs of using scavenged memory in its pacing.
+	scavengeCostRatio = 0.7 * (goos.IsDarwin + goos.IsIos)
+)
+
+// heapRetained returns an estimate of the current heap RSS.
+func heapRetained() uint64 {
+	return gcController.heapInUse.load() + gcController.heapFree.load()
+}
+
+// gcPaceScavenger updates the scavenger's pacing, particularly
+// its rate and RSS goal. For this, it requires the current heapGoal,
+// and the heapGoal for the previous GC cycle.
+//
+// The RSS goal is based on the current heap goal with a small overhead
+// to accommodate non-determinism in the allocator.
+//
+// The pacing is based on scavengePageRate, which applies to both regular and
+// huge pages. See that constant for more information.
+//
+// Must be called whenever GC pacing is updated.
+//
+// mheap_.lock must be held or the world must be stopped.
+func gcPaceScavenger(memoryLimit int64, heapGoal, lastHeapGoal uint64) {
+	assertWorldStoppedOrLockHeld(&mheap_.lock)
+
+	// As described at the top of this file, there are two scavenge goals here: one
+	// for gcPercent and one for memoryLimit. Let's handle the latter first because
+	// it's simpler.
+
+	// We want to target retaining (100-reduceExtraPercent)% of the heap.
+	memoryLimitGoal := uint64(float64(memoryLimit) * (100.0 - reduceExtraPercent))
+
+	// mappedReady is comparable to memoryLimit, and represents how much total memory
+	// the Go runtime has committed now (estimated).
+	mappedReady := gcController.mappedReady.Load()
+
+	// If we're below the goal already indicate that we don't need the background
+	// scavenger for the memory limit. This may seems worrisome at first, but note
+	// that the allocator will assist the background scavenger in the face of a memory
+	// limit, so we'll be safe even if we stop the scavenger when we shouldn't have.
+	if mappedReady <= memoryLimitGoal {
+		scavenge.memoryLimitGoal.Store(^uint64(0))
+	} else {
+		scavenge.memoryLimitGoal.Store(memoryLimitGoal)
+	}
+
+	// Now handle the gcPercent goal.
+
+	// If we're called before the first GC completed, disable scavenging.
+	// We never scavenge before the 2nd GC cycle anyway (we don't have enough
+	// information about the heap yet) so this is fine, and avoids a fault
+	// or garbage data later.
+	if lastHeapGoal == 0 {
+		scavenge.gcPercentGoal.Store(^uint64(0))
+		return
+	}
+	// Compute our scavenging goal.
+	goalRatio := float64(heapGoal) / float64(lastHeapGoal)
+	gcPercentGoal := uint64(float64(memstats.lastHeapInUse) * goalRatio)
+	// Add retainExtraPercent overhead to retainedGoal. This calculation
+	// looks strange but the purpose is to arrive at an integer division
+	// (e.g. if retainExtraPercent = 12.5, then we get a divisor of 8)
+	// that also avoids the overflow from a multiplication.
+	gcPercentGoal += gcPercentGoal / (1.0 / (retainExtraPercent / 100.0))
+	// Align it to a physical page boundary to make the following calculations
+	// a bit more exact.
+	gcPercentGoal = (gcPercentGoal + uint64(physPageSize) - 1) &^ (uint64(physPageSize) - 1)
+
+	// Represents where we are now in the heap's contribution to RSS in bytes.
+	//
+	// Guaranteed to always be a multiple of physPageSize on systems where
+	// physPageSize <= pageSize since we map new heap memory at a size larger than
+	// any physPageSize and released memory in multiples of the physPageSize.
+	//
+	// However, certain functions recategorize heap memory as other stats (e.g.
+	// stacks) and this happens in multiples of pageSize, so on systems
+	// where physPageSize > pageSize the calculations below will not be exact.
+	// Generally this is OK since we'll be off by at most one regular
+	// physical page.
+	heapRetainedNow := heapRetained()
+
+	// If we're already below our goal, or within one page of our goal, then indicate
+	// that we don't need the background scavenger for maintaining a memory overhead
+	// proportional to the heap goal.
+	if heapRetainedNow <= gcPercentGoal || heapRetainedNow-gcPercentGoal < uint64(physPageSize) {
+		scavenge.gcPercentGoal.Store(^uint64(0))
+	} else {
+		scavenge.gcPercentGoal.Store(gcPercentGoal)
+	}
+}
+
+var scavenge struct {
+	// gcPercentGoal is the amount of retained heap memory (measured by
+	// heapRetained) that the runtime will try to maintain by returning
+	// memory to the OS. This goal is derived from gcController.gcPercent
+	// by choosing to retain enough memory to allocate heap memory up to
+	// the heap goal.
+	gcPercentGoal atomic.Uint64
+
+	// memoryLimitGoal is the amount of memory retained by the runtime (
+	// measured by gcController.mappedReady) that the runtime will try to
+	// maintain by returning memory to the OS. This goal is derived from
+	// gcController.memoryLimit by choosing to target the memory limit or
+	// some lower target to keep the scavenger working.
+	memoryLimitGoal atomic.Uint64
+}
+
+const (
+	// It doesn't really matter what value we start at, but we can't be zero, because
+	// that'll cause divide-by-zero issues. Pick something conservative which we'll
+	// also use as a fallback.
+	startingScavSleepRatio = 0.001
+
+	// Spend at least 1 ms scavenging, otherwise the corresponding
+	// sleep time to maintain our desired utilization is too low to
+	// be reliable.
+	minScavWorkTime = 1e6
+)
+
+// Sleep/wait state of the background scavenger.
+var scavenger scavengerState
+
+type scavengerState struct {
+	// lock protects all fields below.
+	lock mutex
+
+	// g is the goroutine the scavenger is bound to.
+	g *g
+
+	// parked is whether or not the scavenger is parked.
+	parked bool
+
+	// timer is the timer used for the scavenger to sleep.
+	timer *timer
+
+	// sysmonWake signals to sysmon that it should wake the scavenger.
+	sysmonWake atomic.Uint32
+
+	// targetCPUFraction is the target CPU overhead for the scavenger.
+	targetCPUFraction float64
+
+	// sleepRatio is the ratio of time spent doing scavenging work to
+	// time spent sleeping. This is used to decide how long the scavenger
+	// should sleep for in between batches of work. It is set by
+	// critSleepController in order to maintain a CPU overhead of
+	// targetCPUFraction.
+	//
+	// Lower means more sleep, higher means more aggressive scavenging.
+	sleepRatio float64
+
+	// sleepController controls sleepRatio.
+	//
+	// See sleepRatio for more details.
+	sleepController piController
+
+	// cooldown is the time left in nanoseconds during which we avoid
+	// using the controller and we hold sleepRatio at a conservative
+	// value. Used if the controller's assumptions fail to hold.
+	controllerCooldown int64
+
+	// printControllerReset instructs printScavTrace to signal that
+	// the controller was reset.
+	printControllerReset bool
+
+	// sleepStub is a stub used for testing to avoid actually having
+	// the scavenger sleep.
+	//
+	// Unlike the other stubs, this is not populated if left nil
+	// Instead, it is called when non-nil because any valid implementation
+	// of this function basically requires closing over this scavenger
+	// state, and allocating a closure is not allowed in the runtime as
+	// a matter of policy.
+	sleepStub func(n int64) int64
+
+	// scavenge is a function that scavenges n bytes of memory.
+	// Returns how many bytes of memory it actually scavenged, as
+	// well as the time it took in nanoseconds. Usually mheap.pages.scavenge
+	// with nanotime called around it, but stubbed out for testing.
+	// Like mheap.pages.scavenge, if it scavenges less than n bytes of
+	// memory, the caller may assume the heap is exhausted of scavengable
+	// memory for now.
+	//
+	// If this is nil, it is populated with the real thing in init.
+	scavenge func(n uintptr) (uintptr, int64)
+
+	// shouldStop is a callback called in the work loop and provides a
+	// point that can force the scavenger to stop early, for example because
+	// the scavenge policy dictates too much has been scavenged already.
+	//
+	// If this is nil, it is populated with the real thing in init.
+	shouldStop func() bool
+
+	// gomaxprocs returns the current value of gomaxprocs. Stub for testing.
+	//
+	// If this is nil, it is populated with the real thing in init.
+	gomaxprocs func() int32
+}
+
+// init initializes a scavenger state and wires to the current G.
+//
+// Must be called from a regular goroutine that can allocate.
+func (s *scavengerState) init() {
+	if s.g != nil {
+		throw("scavenger state is already wired")
+	}
+	lockInit(&s.lock, lockRankScavenge)
+	s.g = getg()
+
+	s.timer = new(timer)
+	s.timer.arg = s
+	s.timer.f = func(s any, _ uintptr) {
+		s.(*scavengerState).wake()
+	}
+
+	// input: fraction of CPU time actually used.
+	// setpoint: ideal CPU fraction.
+	// output: ratio of time worked to time slept (determines sleep time).
+	//
+	// The output of this controller is somewhat indirect to what we actually
+	// want to achieve: how much time to sleep for. The reason for this definition
+	// is to ensure that the controller's outputs have a direct relationship with
+	// its inputs (as opposed to an inverse relationship), making it somewhat
+	// easier to reason about for tuning purposes.
+	s.sleepController = piController{
+		// Tuned loosely via Ziegler-Nichols process.
+		kp: 0.3375,
+		ti: 3.2e6,
+		tt: 1e9, // 1 second reset time.
+
+		// These ranges seem wide, but we want to give the controller plenty of
+		// room to hunt for the optimal value.
+		min: 0.001,  // 1:1000
+		max: 1000.0, // 1000:1
+	}
+	s.sleepRatio = startingScavSleepRatio
+
+	// Install real functions if stubs aren't present.
+	if s.scavenge == nil {
+		s.scavenge = func(n uintptr) (uintptr, int64) {
+			start := nanotime()
+			r := mheap_.pages.scavenge(n, nil)
+			end := nanotime()
+			if start >= end {
+				return r, 0
+			}
+			return r, end - start
+		}
+	}
+	if s.shouldStop == nil {
+		s.shouldStop = func() bool {
+			// If background scavenging is disabled or if there's no work to do just stop.
+			return heapRetained() <= scavenge.gcPercentGoal.Load() &&
+				(!go119MemoryLimitSupport ||
+					gcController.mappedReady.Load() <= scavenge.memoryLimitGoal.Load())
+		}
+	}
+	if s.gomaxprocs == nil {
+		s.gomaxprocs = func() int32 {
+			return gomaxprocs
+		}
+	}
+}
+
+// park parks the scavenger goroutine.
+func (s *scavengerState) park() {
+	lock(&s.lock)
+	if getg() != s.g {
+		throw("tried to park scavenger from another goroutine")
+	}
+	s.parked = true
+	goparkunlock(&s.lock, waitReasonGCScavengeWait, traceEvGoBlock, 2)
+}
+
+// ready signals to sysmon that the scavenger should be awoken.
+func (s *scavengerState) ready() {
+	s.sysmonWake.Store(1)
+}
+
+// wake immediately unparks the scavenger if necessary.
+//
+// Safe to run without a P.
+func (s *scavengerState) wake() {
+	lock(&s.lock)
+	if s.parked {
+		// Unset sysmonWake, since the scavenger is now being awoken.
+		s.sysmonWake.Store(0)
+
+		// s.parked is unset to prevent a double wake-up.
+		s.parked = false
+
+		// Ready the goroutine by injecting it. We use injectglist instead
+		// of ready or goready in order to allow us to run this function
+		// without a P. injectglist also avoids placing the goroutine in
+		// the current P's runnext slot, which is desirable to prevent
+		// the scavenger from interfering with user goroutine scheduling
+		// too much.
+		var list gList
+		list.push(s.g)
+		injectglist(&list)
+	}
+	unlock(&s.lock)
+}
+
+// sleep puts the scavenger to sleep based on the amount of time that it worked
+// in nanoseconds.
+//
+// Note that this function should only be called by the scavenger.
+//
+// The scavenger may be woken up earlier by a pacing change, and it may not go
+// to sleep at all if there's a pending pacing change.
+func (s *scavengerState) sleep(worked float64) {
+	lock(&s.lock)
+	if getg() != s.g {
+		throw("tried to sleep scavenger from another goroutine")
+	}
+
+	if worked < minScavWorkTime {
+		// This means there wasn't enough work to actually fill up minScavWorkTime.
+		// That's fine; we shouldn't try to do anything with this information
+		// because it's going result in a short enough sleep request that things
+		// will get messy. Just assume we did at least this much work.
+		// All this means is that we'll sleep longer than we otherwise would have.
+		worked = minScavWorkTime
+	}
+
+	// Multiply the critical time by 1 + the ratio of the costs of using
+	// scavenged memory vs. scavenging memory. This forces us to pay down
+	// the cost of reusing this memory eagerly by sleeping for a longer period
+	// of time and scavenging less frequently. More concretely, we avoid situations
+	// where we end up scavenging so often that we hurt allocation performance
+	// because of the additional overheads of using scavenged memory.
+	worked *= 1 + scavengeCostRatio
+
+	// sleepTime is the amount of time we're going to sleep, based on the amount
+	// of time we worked, and the sleepRatio.
+	sleepTime := int64(worked / s.sleepRatio)
+
+	var slept int64
+	if s.sleepStub == nil {
+		// Set the timer.
+		//
+		// This must happen here instead of inside gopark
+		// because we can't close over any variables without
+		// failing escape analysis.
+		start := nanotime()
+		resetTimer(s.timer, start+sleepTime)
+
+		// Mark ourselves as asleep and go to sleep.
+		s.parked = true
+		goparkunlock(&s.lock, waitReasonSleep, traceEvGoSleep, 2)
+
+		// How long we actually slept for.
+		slept = nanotime() - start
+
+		lock(&s.lock)
+		// Stop the timer here because s.wake is unable to do it for us.
+		// We don't really care if we succeed in stopping the timer. One
+		// reason we might fail is that we've already woken up, but the timer
+		// might be in the process of firing on some other P; essentially we're
+		// racing with it. That's totally OK. Double wake-ups are perfectly safe.
+		stopTimer(s.timer)
+		unlock(&s.lock)
+	} else {
+		unlock(&s.lock)
+		slept = s.sleepStub(sleepTime)
+	}
+
+	// Stop here if we're cooling down from the controller.
+	if s.controllerCooldown > 0 {
+		// worked and slept aren't exact measures of time, but it's OK to be a bit
+		// sloppy here. We're just hoping we're avoiding some transient bad behavior.
+		t := slept + int64(worked)
+		if t > s.controllerCooldown {
+			s.controllerCooldown = 0
+		} else {
+			s.controllerCooldown -= t
+		}
+		return
+	}
+
+	// idealFraction is the ideal % of overall application CPU time that we
+	// spend scavenging.
+	idealFraction := float64(scavengePercent) / 100.0
+
+	// Calculate the CPU time spent.
+	//
+	// This may be slightly inaccurate with respect to GOMAXPROCS, but we're
+	// recomputing this often enough relative to GOMAXPROCS changes in general
+	// (it only changes when the world is stopped, and not during a GC) that
+	// that small inaccuracy is in the noise.
+	cpuFraction := worked / ((float64(slept) + worked) * float64(s.gomaxprocs()))
+
+	// Update the critSleepRatio, adjusting until we reach our ideal fraction.
+	var ok bool
+	s.sleepRatio, ok = s.sleepController.next(cpuFraction, idealFraction, float64(slept)+worked)
+	if !ok {
+		// The core assumption of the controller, that we can get a proportional
+		// response, broke down. This may be transient, so temporarily switch to
+		// sleeping a fixed, conservative amount.
+		s.sleepRatio = startingScavSleepRatio
+		s.controllerCooldown = 5e9 // 5 seconds.
+
+		// Signal the scav trace printer to output this.
+		s.controllerFailed()
+	}
+}
+
+// controllerFailed indicates that the scavenger's scheduling
+// controller failed.
+func (s *scavengerState) controllerFailed() {
+	lock(&s.lock)
+	s.printControllerReset = true
+	unlock(&s.lock)
+}
+
+// run is the body of the main scavenging loop.
+//
+// Returns the number of bytes released and the estimated time spent
+// releasing those bytes.
+//
+// Must be run on the scavenger goroutine.
+func (s *scavengerState) run() (released uintptr, worked float64) {
+	lock(&s.lock)
+	if getg() != s.g {
+		throw("tried to run scavenger from another goroutine")
+	}
+	unlock(&s.lock)
+
+	for worked < minScavWorkTime {
+		// If something from outside tells us to stop early, stop.
+		if s.shouldStop() {
+			break
+		}
+
+		// scavengeQuantum is the amount of memory we try to scavenge
+		// in one go. A smaller value means the scavenger is more responsive
+		// to the scheduler in case of e.g. preemption. A larger value means
+		// that the overheads of scavenging are better amortized, so better
+		// scavenging throughput.
+		//
+		// The current value is chosen assuming a cost of ~10µs/physical page
+		// (this is somewhat pessimistic), which implies a worst-case latency of
+		// about 160µs for 4 KiB physical pages. The current value is biased
+		// toward latency over throughput.
+		const scavengeQuantum = 64 << 10
+
+		// Accumulate the amount of time spent scavenging.
+		r, duration := s.scavenge(scavengeQuantum)
+
+		// On some platforms we may see end >= start if the time it takes to scavenge
+		// memory is less than the minimum granularity of its clock (e.g. Windows) or
+		// due to clock bugs.
+		//
+		// In this case, just assume scavenging takes 10 µs per regular physical page
+		// (determined empirically), and conservatively ignore the impact of huge pages
+		// on timing.
+		const approxWorkedNSPerPhysicalPage = 10e3
+		if duration == 0 {
+			worked += approxWorkedNSPerPhysicalPage * float64(r/physPageSize)
+		} else {
+			// TODO(mknyszek): If duration is small compared to worked, it could be
+			// rounded down to zero. Probably not a problem in practice because the
+			// values are all within a few orders of magnitude of each other but maybe
+			// worth worrying about.
+			worked += float64(duration)
+		}
+		released += r
+
+		// scavenge does not return until it either finds the requisite amount of
+		// memory to scavenge, or exhausts the heap. If we haven't found enough
+		// to scavenge, then the heap must be exhausted.
+		if r < scavengeQuantum {
+			break
+		}
+		// When using fake time just do one loop.
+		if faketime != 0 {
+			break
+		}
+	}
+	if released > 0 && released < physPageSize {
+		// If this happens, it means that we may have attempted to release part
+		// of a physical page, but the likely effect of that is that it released
+		// the whole physical page, some of which may have still been in-use.
+		// This could lead to memory corruption. Throw.
+		throw("released less than one physical page of memory")
+	}
+	return
+}
+
+// Background scavenger.
+//
+// The background scavenger maintains the RSS of the application below
+// the line described by the proportional scavenging statistics in
+// the mheap struct.
+func bgscavenge(c chan int) {
+	scavenger.init()
+
+	c <- 1
+	scavenger.park()
+
+	for {
+		released, workTime := scavenger.run()
+		if released == 0 {
+			scavenger.park()
+			continue
+		}
+		atomic.Xadduintptr(&mheap_.pages.scav.released, released)
+		scavenger.sleep(workTime)
+	}
+}
+
+// scavenge scavenges nbytes worth of free pages, starting with the
+// highest address first. Successive calls continue from where it left
+// off until the heap is exhausted. Call scavengeStartGen to bring it
+// back to the top of the heap.
+//
+// Returns the amount of memory scavenged in bytes.
+//
+// scavenge always tries to scavenge nbytes worth of memory, and will
+// only fail to do so if the heap is exhausted for now.
+func (p *pageAlloc) scavenge(nbytes uintptr, shouldStop func() bool) uintptr {
+	released := uintptr(0)
+	for released < nbytes {
+		ci, pageIdx := p.scav.index.find()
+		if ci == 0 {
+			break
+		}
+		systemstack(func() {
+			released += p.scavengeOne(ci, pageIdx, nbytes-released)
+		})
+		if shouldStop != nil && shouldStop() {
+			break
+		}
+	}
+	return released
+}
+
+// printScavTrace prints a scavenge trace line to standard error.
+//
+// released should be the amount of memory released since the last time this
+// was called, and forced indicates whether the scavenge was forced by the
+// application.
+//
+// scavenger.lock must be held.
+func printScavTrace(released uintptr, forced bool) {
+	assertLockHeld(&scavenger.lock)
+
+	printlock()
+	print("scav ",
+		released>>10, " KiB work, ",
+		gcController.heapReleased.load()>>10, " KiB total, ",
+		(gcController.heapInUse.load()*100)/heapRetained(), "% util",
+	)
+	if forced {
+		print(" (forced)")
+	} else if scavenger.printControllerReset {
+		print(" [controller reset]")
+		scavenger.printControllerReset = false
+	}
+	println()
+	printunlock()
+}
+
+// scavengeOne walks over the chunk at chunk index ci and searches for
+// a contiguous run of pages to scavenge. It will try to scavenge
+// at most max bytes at once, but may scavenge more to avoid
+// breaking huge pages. Once it scavenges some memory it returns
+// how much it scavenged in bytes.
+//
+// searchIdx is the page index to start searching from in ci.
+//
+// Returns the number of bytes scavenged.
+//
+// Must run on the systemstack because it acquires p.mheapLock.
+//
+//go:systemstack
+func (p *pageAlloc) scavengeOne(ci chunkIdx, searchIdx uint, max uintptr) uintptr {
+	// Calculate the maximum number of pages to scavenge.
+	//
+	// This should be alignUp(max, pageSize) / pageSize but max can and will
+	// be ^uintptr(0), so we need to be very careful not to overflow here.
+	// Rather than use alignUp, calculate the number of pages rounded down
+	// first, then add back one if necessary.
+	maxPages := max / pageSize
+	if max%pageSize != 0 {
+		maxPages++
+	}
+
+	// Calculate the minimum number of pages we can scavenge.
+	//
+	// Because we can only scavenge whole physical pages, we must
+	// ensure that we scavenge at least minPages each time, aligned
+	// to minPages*pageSize.
+	minPages := physPageSize / pageSize
+	if minPages < 1 {
+		minPages = 1
+	}
+
+	lock(p.mheapLock)
+	if p.summary[len(p.summary)-1][ci].max() >= uint(minPages) {
+		// We only bother looking for a candidate if there at least
+		// minPages free pages at all.
+		base, npages := p.chunkOf(ci).findScavengeCandidate(pallocChunkPages-1, minPages, maxPages)
+
+		// If we found something, scavenge it and return!
+		if npages != 0 {
+			// Compute the full address for the start of the range.
+			addr := chunkBase(ci) + uintptr(base)*pageSize
+
+			// Mark the range we're about to scavenge as allocated, because
+			// we don't want any allocating goroutines to grab it while
+			// the scavenging is in progress.
+			if scav := p.allocRange(addr, uintptr(npages)); scav != 0 {
+				throw("double scavenge")
+			}
+
+			// With that done, it's safe to unlock.
+			unlock(p.mheapLock)
+
+			if !p.test {
+				// Only perform the actual scavenging if we're not in a test.
+				// It's dangerous to do so otherwise.
+				sysUnused(unsafe.Pointer(addr), uintptr(npages)*pageSize)
+
+				// Update global accounting only when not in test, otherwise
+				// the runtime's accounting will be wrong.
+				nbytes := int64(npages) * pageSize
+				gcController.heapReleased.add(nbytes)
+				gcController.heapFree.add(-nbytes)
+
+				stats := memstats.heapStats.acquire()
+				atomic.Xaddint64(&stats.committed, -nbytes)
+				atomic.Xaddint64(&stats.released, nbytes)
+				memstats.heapStats.release()
+			}
+
+			// Relock the heap, because now we need to make these pages
+			// available allocation. Free them back to the page allocator.
+			lock(p.mheapLock)
+			p.free(addr, uintptr(npages), true)
+
+			// Mark the range as scavenged.
+			p.chunkOf(ci).scavenged.setRange(base, npages)
+			unlock(p.mheapLock)
+
+			return uintptr(npages) * pageSize
+		}
+	}
+	// Mark this chunk as having no free pages.
+	p.scav.index.clear(ci)
+	unlock(p.mheapLock)
+
+	return 0
+}
+
+// fillAligned returns x but with all zeroes in m-aligned
+// groups of m bits set to 1 if any bit in the group is non-zero.
+//
+// For example, fillAligned(0x0100a3, 8) == 0xff00ff.
+//
+// Note that if m == 1, this is a no-op.
+//
+// m must be a power of 2 <= maxPagesPerPhysPage.
+func fillAligned(x uint64, m uint) uint64 {
+	apply := func(x uint64, c uint64) uint64 {
+		// The technique used it here is derived from
+		// https://graphics.stanford.edu/~seander/bithacks.html#ZeroInWord
+		// and extended for more than just bytes (like nibbles
+		// and uint16s) by using an appropriate constant.
+		//
+		// To summarize the technique, quoting from that page:
+		// "[It] works by first zeroing the high bits of the [8]
+		// bytes in the word. Subsequently, it adds a number that
+		// will result in an overflow to the high bit of a byte if
+		// any of the low bits were initially set. Next the high
+		// bits of the original word are ORed with these values;
+		// thus, the high bit of a byte is set iff any bit in the
+		// byte was set. Finally, we determine if any of these high
+		// bits are zero by ORing with ones everywhere except the
+		// high bits and inverting the result."
+		return ^((((x & c) + c) | x) | c)
+	}
+	// Transform x to contain a 1 bit at the top of each m-aligned
+	// group of m zero bits.
+	switch m {
+	case 1:
+		return x
+	case 2:
+		x = apply(x, 0x5555555555555555)
+	case 4:
+		x = apply(x, 0x7777777777777777)
+	case 8:
+		x = apply(x, 0x7f7f7f7f7f7f7f7f)
+	case 16:
+		x = apply(x, 0x7fff7fff7fff7fff)
+	case 32:
+		x = apply(x, 0x7fffffff7fffffff)
+	case 64: // == maxPagesPerPhysPage
+		x = apply(x, 0x7fffffffffffffff)
+	default:
+		throw("bad m value")
+	}
+	// Now, the top bit of each m-aligned group in x is set
+	// that group was all zero in the original x.
+
+	// From each group of m bits subtract 1.
+	// Because we know only the top bits of each
+	// m-aligned group are set, we know this will
+	// set each group to have all the bits set except
+	// the top bit, so just OR with the original
+	// result to set all the bits.
+	return ^((x - (x >> (m - 1))) | x)
+}
+
+// findScavengeCandidate returns a start index and a size for this pallocData
+// segment which represents a contiguous region of free and unscavenged memory.
+//
+// searchIdx indicates the page index within this chunk to start the search, but
+// note that findScavengeCandidate searches backwards through the pallocData. As a
+// a result, it will return the highest scavenge candidate in address order.
+//
+// min indicates a hard minimum size and alignment for runs of pages. That is,
+// findScavengeCandidate will not return a region smaller than min pages in size,
+// or that is min pages or greater in size but not aligned to min. min must be
+// a non-zero power of 2 <= maxPagesPerPhysPage.
+//
+// max is a hint for how big of a region is desired. If max >= pallocChunkPages, then
+// findScavengeCandidate effectively returns entire free and unscavenged regions.
+// If max < pallocChunkPages, it may truncate the returned region such that size is
+// max. However, findScavengeCandidate may still return a larger region if, for
+// example, it chooses to preserve huge pages, or if max is not aligned to min (it
+// will round up). That is, even if max is small, the returned size is not guaranteed
+// to be equal to max. max is allowed to be less than min, in which case it is as if
+// max == min.
+func (m *pallocData) findScavengeCandidate(searchIdx uint, min, max uintptr) (uint, uint) {
+	if min&(min-1) != 0 || min == 0 {
+		print("runtime: min = ", min, "\n")
+		throw("min must be a non-zero power of 2")
+	} else if min > maxPagesPerPhysPage {
+		print("runtime: min = ", min, "\n")
+		throw("min too large")
+	}
+	// max may not be min-aligned, so we might accidentally truncate to
+	// a max value which causes us to return a non-min-aligned value.
+	// To prevent this, align max up to a multiple of min (which is always
+	// a power of 2). This also prevents max from ever being less than
+	// min, unless it's zero, so handle that explicitly.
+	if max == 0 {
+		max = min
+	} else {
+		max = alignUp(max, min)
+	}
+
+	i := int(searchIdx / 64)
+	// Start by quickly skipping over blocks of non-free or scavenged pages.
+	for ; i >= 0; i-- {
+		// 1s are scavenged OR non-free => 0s are unscavenged AND free
+		x := fillAligned(m.scavenged[i]|m.pallocBits[i], uint(min))
+		if x != ^uint64(0) {
+			break
+		}
+	}
+	if i < 0 {
+		// Failed to find any free/unscavenged pages.
+		return 0, 0
+	}
+	// We have something in the 64-bit chunk at i, but it could
+	// extend further. Loop until we find the extent of it.
+
+	// 1s are scavenged OR non-free => 0s are unscavenged AND free
+	x := fillAligned(m.scavenged[i]|m.pallocBits[i], uint(min))
+	z1 := uint(sys.LeadingZeros64(^x))
+	run, end := uint(0), uint(i)*64+(64-z1)
+	if x<<z1 != 0 {
+		// After shifting out z1 bits, we still have 1s,
+		// so the run ends inside this word.
+		run = uint(sys.LeadingZeros64(x << z1))
+	} else {
+		// After shifting out z1 bits, we have no more 1s.
+		// This means the run extends to the bottom of the
+		// word so it may extend into further words.
+		run = 64 - z1
+		for j := i - 1; j >= 0; j-- {
+			x := fillAligned(m.scavenged[j]|m.pallocBits[j], uint(min))
+			run += uint(sys.LeadingZeros64(x))
+			if x != 0 {
+				// The run stopped in this word.
+				break
+			}
+		}
+	}
+
+	// Split the run we found if it's larger than max but hold on to
+	// our original length, since we may need it later.
+	size := run
+	if size > uint(max) {
+		size = uint(max)
+	}
+	start := end - size
+
+	// Each huge page is guaranteed to fit in a single palloc chunk.
+	//
+	// TODO(mknyszek): Support larger huge page sizes.
+	// TODO(mknyszek): Consider taking pages-per-huge-page as a parameter
+	// so we can write tests for this.
+	if physHugePageSize > pageSize && physHugePageSize > physPageSize {
+		// We have huge pages, so let's ensure we don't break one by scavenging
+		// over a huge page boundary. If the range [start, start+size) overlaps with
+		// a free-and-unscavenged huge page, we want to grow the region we scavenge
+		// to include that huge page.
+
+		// Compute the huge page boundary above our candidate.
+		pagesPerHugePage := uintptr(physHugePageSize / pageSize)
+		hugePageAbove := uint(alignUp(uintptr(start), pagesPerHugePage))
+
+		// If that boundary is within our current candidate, then we may be breaking
+		// a huge page.
+		if hugePageAbove <= end {
+			// Compute the huge page boundary below our candidate.
+			hugePageBelow := uint(alignDown(uintptr(start), pagesPerHugePage))
+
+			if hugePageBelow >= end-run {
+				// We're in danger of breaking apart a huge page since start+size crosses
+				// a huge page boundary and rounding down start to the nearest huge
+				// page boundary is included in the full run we found. Include the entire
+				// huge page in the bound by rounding down to the huge page size.
+				size = size + (start - hugePageBelow)
+				start = hugePageBelow
+			}
+		}
+	}
+	return start, size
+}
+
+// scavengeIndex is a structure for efficiently managing which pageAlloc chunks have
+// memory available to scavenge.
+type scavengeIndex struct {
+	// chunks is a bitmap representing the entire address space. Each bit represents
+	// a single chunk, and a 1 value indicates the presence of pages available for
+	// scavenging. Updates to the bitmap are serialized by the pageAlloc lock.
+	//
+	// The underlying storage of chunks is platform dependent and may not even be
+	// totally mapped read/write. min and max reflect the extent that is safe to access.
+	// min is inclusive, max is exclusive.
+	//
+	// searchAddr is the maximum address (in the offset address space, so we have a linear
+	// view of the address space; see mranges.go:offAddr) containing memory available to
+	// scavenge. It is a hint to the find operation to avoid O(n^2) behavior in repeated lookups.
+	//
+	// searchAddr is always inclusive and should be the base address of the highest runtime
+	// page available for scavenging.
+	//
+	// searchAddr is managed by both find and mark.
+	//
+	// Normally, find monotonically decreases searchAddr as it finds no more free pages to
+	// scavenge. However, mark, when marking a new chunk at an index greater than the current
+	// searchAddr, sets searchAddr to the *negative* index into chunks of that page. The trick here
+	// is that concurrent calls to find will fail to monotonically decrease searchAddr, and so they
+	// won't barge over new memory becoming available to scavenge. Furthermore, this ensures
+	// that some future caller of find *must* observe the new high index. That caller
+	// (or any other racing with it), then makes searchAddr positive before continuing, bringing
+	// us back to our monotonically decreasing steady-state.
+	//
+	// A pageAlloc lock serializes updates between min, max, and searchAddr, so abs(searchAddr)
+	// is always guaranteed to be >= min and < max (converted to heap addresses).
+	//
+	// TODO(mknyszek): Ideally we would use something bigger than a uint8 for faster
+	// iteration like uint32, but we lack the bit twiddling intrinsics. We'd need to either
+	// copy them from math/bits or fix the fact that we can't import math/bits' code from
+	// the runtime due to compiler instrumentation.
+	searchAddr atomicOffAddr
+	chunks     []atomic.Uint8
+	minHeapIdx atomic.Int32
+	min, max   atomic.Int32
+}
+
+// find returns the highest chunk index that may contain pages available to scavenge.
+// It also returns an offset to start searching in the highest chunk.
+func (s *scavengeIndex) find() (chunkIdx, uint) {
+	searchAddr, marked := s.searchAddr.Load()
+	if searchAddr == minOffAddr.addr() {
+		// We got a cleared search addr.
+		return 0, 0
+	}
+
+	// Starting from searchAddr's chunk, and moving down to minHeapIdx,
+	// iterate until we find a chunk with pages to scavenge.
+	min := s.minHeapIdx.Load()
+	searchChunk := chunkIndex(uintptr(searchAddr))
+	start := int32(searchChunk / 8)
+	for i := start; i >= min; i-- {
+		// Skip over irrelevant address space.
+		chunks := s.chunks[i].Load()
+		if chunks == 0 {
+			continue
+		}
+		// Note that we can't have 8 leading zeroes here because
+		// we necessarily skipped that case. So, what's left is
+		// an index. If there are no zeroes, we want the 7th
+		// index, if 1 zero, the 6th, and so on.
+		n := 7 - sys.LeadingZeros8(chunks)
+		ci := chunkIdx(uint(i)*8 + uint(n))
+		if searchChunk == ci {
+			return ci, chunkPageIndex(uintptr(searchAddr))
+		}
+		// Try to reduce searchAddr to newSearchAddr.
+		newSearchAddr := chunkBase(ci) + pallocChunkBytes - pageSize
+		if marked {
+			// Attempt to be the first one to decrease the searchAddr
+			// after an increase. If we fail, that means there was another
+			// increase, or somebody else got to it before us. Either way,
+			// it doesn't matter. We may lose some performance having an
+			// incorrect search address, but it's far more important that
+			// we don't miss updates.
+			s.searchAddr.StoreUnmark(searchAddr, newSearchAddr)
+		} else {
+			// Decrease searchAddr.
+			s.searchAddr.StoreMin(newSearchAddr)
+		}
+		return ci, pallocChunkPages - 1
+	}
+	// Clear searchAddr, because we've exhausted the heap.
+	s.searchAddr.Clear()
+	return 0, 0
+}
+
+// mark sets the inclusive range of chunks between indices start and end as
+// containing pages available to scavenge.
+//
+// Must be serialized with other mark, markRange, and clear calls.
+func (s *scavengeIndex) mark(base, limit uintptr) {
+	start, end := chunkIndex(base), chunkIndex(limit-pageSize)
+	if start == end {
+		// Within a chunk.
+		mask := uint8(1 << (start % 8))
+		s.chunks[start/8].Or(mask)
+	} else if start/8 == end/8 {
+		// Within the same byte in the index.
+		mask := uint8(uint16(1<<(end-start+1))-1) << (start % 8)
+		s.chunks[start/8].Or(mask)
+	} else {
+		// Crosses multiple bytes in the index.
+		startAligned := chunkIdx(alignUp(uintptr(start), 8))
+		endAligned := chunkIdx(alignDown(uintptr(end), 8))
+
+		// Do the end of the first byte first.
+		if width := startAligned - start; width > 0 {
+			mask := uint8(uint16(1<<width)-1) << (start % 8)
+			s.chunks[start/8].Or(mask)
+		}
+		// Do the middle aligned sections that take up a whole
+		// byte.
+		for ci := startAligned; ci < endAligned; ci += 8 {
+			s.chunks[ci/8].Store(^uint8(0))
+		}
+		// Do the end of the last byte.
+		//
+		// This width check doesn't match the one above
+		// for start because aligning down into the endAligned
+		// block means we always have at least one chunk in this
+		// block (note that end is *inclusive*). This also means
+		// that if end == endAligned+n, then what we really want
+		// is to fill n+1 chunks, i.e. width n+1. By induction,
+		// this is true for all n.
+		if width := end - endAligned + 1; width > 0 {
+			mask := uint8(uint16(1<<width) - 1)
+			s.chunks[end/8].Or(mask)
+		}
+	}
+	newSearchAddr := limit - pageSize
+	searchAddr, _ := s.searchAddr.Load()
+	// N.B. Because mark is serialized, it's not necessary to do a
+	// full CAS here. mark only ever increases searchAddr, while
+	// find only ever decreases it. Since we only ever race with
+	// decreases, even if the value we loaded is stale, the actual
+	// value will never be larger.
+	if (offAddr{searchAddr}).lessThan(offAddr{newSearchAddr}) {
+		s.searchAddr.StoreMarked(newSearchAddr)
+	}
+}
+
+// clear sets the chunk at index ci as not containing pages available to scavenge.
+//
+// Must be serialized with other mark, markRange, and clear calls.
+func (s *scavengeIndex) clear(ci chunkIdx) {
+	s.chunks[ci/8].And(^uint8(1 << (ci % 8)))
+}
diff --git a/contrib/go/_std_1.19/src/runtime/mgcstack.go b/contrib/go/_std_1.19/src/runtime/mgcstack.go
new file mode 100644
index 0000000000..472c61a491
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/mgcstack.go
@@ -0,0 +1,353 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Garbage collector: stack objects and stack tracing
+// See the design doc at https://docs.google.com/document/d/1un-Jn47yByHL7I0aVIP_uVCMxjdM5mpelJhiKlIqxkE/edit?usp=sharing
+// Also see issue 22350.
+
+// Stack tracing solves the problem of determining which parts of the
+// stack are live and should be scanned. It runs as part of scanning
+// a single goroutine stack.
+//
+// Normally determining which parts of the stack are live is easy to
+// do statically, as user code has explicit references (reads and
+// writes) to stack variables. The compiler can do a simple dataflow
+// analysis to determine liveness of stack variables at every point in
+// the code. See cmd/compile/internal/gc/plive.go for that analysis.
+//
+// However, when we take the address of a stack variable, determining
+// whether that variable is still live is less clear. We can still
+// look for static accesses, but accesses through a pointer to the
+// variable are difficult in general to track statically. That pointer
+// can be passed among functions on the stack, conditionally retained,
+// etc.
+//
+// Instead, we will track pointers to stack variables dynamically.
+// All pointers to stack-allocated variables will themselves be on the
+// stack somewhere (or in associated locations, like defer records), so
+// we can find them all efficiently.
+//
+// Stack tracing is organized as a mini garbage collection tracing
+// pass. The objects in this garbage collection are all the variables
+// on the stack whose address is taken, and which themselves contain a
+// pointer. We call these variables "stack objects".
+//
+// We begin by determining all the stack objects on the stack and all
+// the statically live pointers that may point into the stack. We then
+// process each pointer to see if it points to a stack object. If it
+// does, we scan that stack object. It may contain pointers into the
+// heap, in which case those pointers are passed to the main garbage
+// collection. It may also contain pointers into the stack, in which
+// case we add them to our set of stack pointers.
+//
+// Once we're done processing all the pointers (including the ones we
+// added during processing), we've found all the stack objects that
+// are live. Any dead stack objects are not scanned and their contents
+// will not keep heap objects live. Unlike the main garbage
+// collection, we can't sweep the dead stack objects; they live on in
+// a moribund state until the stack frame that contains them is
+// popped.
+//
+// A stack can look like this:
+//
+// +----------+
+// | foo()    |
+// | +------+ |
+// | |  A   | | <---\
+// | +------+ |     |
+// |          |     |
+// | +------+ |     |
+// | |  B   | |     |
+// | +------+ |     |
+// |          |     |
+// +----------+     |
+// | bar()    |     |
+// | +------+ |     |
+// | |  C   | | <-\ |
+// | +----|-+ |   | |
+// |      |   |   | |
+// | +----v-+ |   | |
+// | |  D  ---------/
+// | +------+ |   |
+// |          |   |
+// +----------+   |
+// | baz()    |   |
+// | +------+ |   |
+// | |  E  -------/
+// | +------+ |
+// |      ^   |
+// | F: --/   |
+// |          |
+// +----------+
+//
+// foo() calls bar() calls baz(). Each has a frame on the stack.
+// foo() has stack objects A and B.
+// bar() has stack objects C and D, with C pointing to D and D pointing to A.
+// baz() has a stack object E pointing to C, and a local variable F pointing to E.
+//
+// Starting from the pointer in local variable F, we will eventually
+// scan all of E, C, D, and A (in that order). B is never scanned
+// because there is no live pointer to it. If B is also statically
+// dead (meaning that foo() never accesses B again after it calls
+// bar()), then B's pointers into the heap are not considered live.
+
+package runtime
+
+import (
+	"internal/goarch"
+	"unsafe"
+)
+
+const stackTraceDebug = false
+
+// Buffer for pointers found during stack tracing.
+// Must be smaller than or equal to workbuf.
+//
+//go:notinheap
+type stackWorkBuf struct {
+	stackWorkBufHdr
+	obj [(_WorkbufSize - unsafe.Sizeof(stackWorkBufHdr{})) / goarch.PtrSize]uintptr
+}
+
+// Header declaration must come after the buf declaration above, because of issue #14620.
+//
+//go:notinheap
+type stackWorkBufHdr struct {
+	workbufhdr
+	next *stackWorkBuf // linked list of workbufs
+	// Note: we could theoretically repurpose lfnode.next as this next pointer.
+	// It would save 1 word, but that probably isn't worth busting open
+	// the lfnode API.
+}
+
+// Buffer for stack objects found on a goroutine stack.
+// Must be smaller than or equal to workbuf.
+//
+//go:notinheap
+type stackObjectBuf struct {
+	stackObjectBufHdr
+	obj [(_WorkbufSize - unsafe.Sizeof(stackObjectBufHdr{})) / unsafe.Sizeof(stackObject{})]stackObject
+}
+
+//go:notinheap
+type stackObjectBufHdr struct {
+	workbufhdr
+	next *stackObjectBuf
+}
+
+func init() {
+	if unsafe.Sizeof(stackWorkBuf{}) > unsafe.Sizeof(workbuf{}) {
+		panic("stackWorkBuf too big")
+	}
+	if unsafe.Sizeof(stackObjectBuf{}) > unsafe.Sizeof(workbuf{}) {
+		panic("stackObjectBuf too big")
+	}
+}
+
+// A stackObject represents a variable on the stack that has had
+// its address taken.
+//
+//go:notinheap
+type stackObject struct {
+	off   uint32             // offset above stack.lo
+	size  uint32             // size of object
+	r     *stackObjectRecord // info of the object (for ptr/nonptr bits). nil if object has been scanned.
+	left  *stackObject       // objects with lower addresses
+	right *stackObject       // objects with higher addresses
+}
+
+// obj.r = r, but with no write barrier.
+//
+//go:nowritebarrier
+func (obj *stackObject) setRecord(r *stackObjectRecord) {
+	// Types of stack objects are always in read-only memory, not the heap.
+	// So not using a write barrier is ok.
+	*(*uintptr)(unsafe.Pointer(&obj.r)) = uintptr(unsafe.Pointer(r))
+}
+
+// A stackScanState keeps track of the state used during the GC walk
+// of a goroutine.
+type stackScanState struct {
+	cache pcvalueCache
+
+	// stack limits
+	stack stack
+
+	// conservative indicates that the next frame must be scanned conservatively.
+	// This applies only to the innermost frame at an async safe-point.
+	conservative bool
+
+	// buf contains the set of possible pointers to stack objects.
+	// Organized as a LIFO linked list of buffers.
+	// All buffers except possibly the head buffer are full.
+	buf     *stackWorkBuf
+	freeBuf *stackWorkBuf // keep around one free buffer for allocation hysteresis
+
+	// cbuf contains conservative pointers to stack objects. If
+	// all pointers to a stack object are obtained via
+	// conservative scanning, then the stack object may be dead
+	// and may contain dead pointers, so it must be scanned
+	// defensively.
+	cbuf *stackWorkBuf
+
+	// list of stack objects
+	// Objects are in increasing address order.
+	head  *stackObjectBuf
+	tail  *stackObjectBuf
+	nobjs int
+
+	// root of binary tree for fast object lookup by address
+	// Initialized by buildIndex.
+	root *stackObject
+}
+
+// Add p as a potential pointer to a stack object.
+// p must be a stack address.
+func (s *stackScanState) putPtr(p uintptr, conservative bool) {
+	if p < s.stack.lo || p >= s.stack.hi {
+		throw("address not a stack address")
+	}
+	head := &s.buf
+	if conservative {
+		head = &s.cbuf
+	}
+	buf := *head
+	if buf == nil {
+		// Initial setup.
+		buf = (*stackWorkBuf)(unsafe.Pointer(getempty()))
+		buf.nobj = 0
+		buf.next = nil
+		*head = buf
+	} else if buf.nobj == len(buf.obj) {
+		if s.freeBuf != nil {
+			buf = s.freeBuf
+			s.freeBuf = nil
+		} else {
+			buf = (*stackWorkBuf)(unsafe.Pointer(getempty()))
+		}
+		buf.nobj = 0
+		buf.next = *head
+		*head = buf
+	}
+	buf.obj[buf.nobj] = p
+	buf.nobj++
+}
+
+// Remove and return a potential pointer to a stack object.
+// Returns 0 if there are no more pointers available.
+//
+// This prefers non-conservative pointers so we scan stack objects
+// precisely if there are any non-conservative pointers to them.
+func (s *stackScanState) getPtr() (p uintptr, conservative bool) {
+	for _, head := range []**stackWorkBuf{&s.buf, &s.cbuf} {
+		buf := *head
+		if buf == nil {
+			// Never had any data.
+			continue
+		}
+		if buf.nobj == 0 {
+			if s.freeBuf != nil {
+				// Free old freeBuf.
+				putempty((*workbuf)(unsafe.Pointer(s.freeBuf)))
+			}
+			// Move buf to the freeBuf.
+			s.freeBuf = buf
+			buf = buf.next
+			*head = buf
+			if buf == nil {
+				// No more data in this list.
+				continue
+			}
+		}
+		buf.nobj--
+		return buf.obj[buf.nobj], head == &s.cbuf
+	}
+	// No more data in either list.
+	if s.freeBuf != nil {
+		putempty((*workbuf)(unsafe.Pointer(s.freeBuf)))
+		s.freeBuf = nil
+	}
+	return 0, false
+}
+
+// addObject adds a stack object at addr of type typ to the set of stack objects.
+func (s *stackScanState) addObject(addr uintptr, r *stackObjectRecord) {
+	x := s.tail
+	if x == nil {
+		// initial setup
+		x = (*stackObjectBuf)(unsafe.Pointer(getempty()))
+		x.next = nil
+		s.head = x
+		s.tail = x
+	}
+	if x.nobj > 0 && uint32(addr-s.stack.lo) < x.obj[x.nobj-1].off+x.obj[x.nobj-1].size {
+		throw("objects added out of order or overlapping")
+	}
+	if x.nobj == len(x.obj) {
+		// full buffer - allocate a new buffer, add to end of linked list
+		y := (*stackObjectBuf)(unsafe.Pointer(getempty()))
+		y.next = nil
+		x.next = y
+		s.tail = y
+		x = y
+	}
+	obj := &x.obj[x.nobj]
+	x.nobj++
+	obj.off = uint32(addr - s.stack.lo)
+	obj.size = uint32(r.size)
+	obj.setRecord(r)
+	// obj.left and obj.right will be initialized by buildIndex before use.
+	s.nobjs++
+}
+
+// buildIndex initializes s.root to a binary search tree.
+// It should be called after all addObject calls but before
+// any call of findObject.
+func (s *stackScanState) buildIndex() {
+	s.root, _, _ = binarySearchTree(s.head, 0, s.nobjs)
+}
+
+// Build a binary search tree with the n objects in the list
+// x.obj[idx], x.obj[idx+1], ..., x.next.obj[0], ...
+// Returns the root of that tree, and the buf+idx of the nth object after x.obj[idx].
+// (The first object that was not included in the binary search tree.)
+// If n == 0, returns nil, x.
+func binarySearchTree(x *stackObjectBuf, idx int, n int) (root *stackObject, restBuf *stackObjectBuf, restIdx int) {
+	if n == 0 {
+		return nil, x, idx
+	}
+	var left, right *stackObject
+	left, x, idx = binarySearchTree(x, idx, n/2)
+	root = &x.obj[idx]
+	idx++
+	if idx == len(x.obj) {
+		x = x.next
+		idx = 0
+	}
+	right, x, idx = binarySearchTree(x, idx, n-n/2-1)
+	root.left = left
+	root.right = right
+	return root, x, idx
+}
+
+// findObject returns the stack object containing address a, if any.
+// Must have called buildIndex previously.
+func (s *stackScanState) findObject(a uintptr) *stackObject {
+	off := uint32(a - s.stack.lo)
+	obj := s.root
+	for {
+		if obj == nil {
+			return nil
+		}
+		if off < obj.off {
+			obj = obj.left
+			continue
+		}
+		if off >= obj.off+obj.size {
+			obj = obj.right
+			continue
+		}
+		return obj
+	}
+}
diff --git a/contrib/go/_std_1.19/src/runtime/mgcsweep.go b/contrib/go/_std_1.19/src/runtime/mgcsweep.go
new file mode 100644
index 0000000000..de57f18c4f
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/mgcsweep.go
@@ -0,0 +1,889 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Garbage collector: sweeping
+
+// The sweeper consists of two different algorithms:
+//
+// * The object reclaimer finds and frees unmarked slots in spans. It
+//   can free a whole span if none of the objects are marked, but that
+//   isn't its goal. This can be driven either synchronously by
+//   mcentral.cacheSpan for mcentral spans, or asynchronously by
+//   sweepone, which looks at all the mcentral lists.
+//
+// * The span reclaimer looks for spans that contain no marked objects
+//   and frees whole spans. This is a separate algorithm because
+//   freeing whole spans is the hardest task for the object reclaimer,
+//   but is critical when allocating new spans. The entry point for
+//   this is mheap_.reclaim and it's driven by a sequential scan of
+//   the page marks bitmap in the heap arenas.
+//
+// Both algorithms ultimately call mspan.sweep, which sweeps a single
+// heap span.
+
+package runtime
+
+import (
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+var sweep sweepdata
+
+// State of background sweep.
+type sweepdata struct {
+	lock    mutex
+	g       *g
+	parked  bool
+	started bool
+
+	nbgsweep    uint32
+	npausesweep uint32
+
+	// active tracks outstanding sweepers and the sweep
+	// termination condition.
+	active activeSweep
+
+	// centralIndex is the current unswept span class.
+	// It represents an index into the mcentral span
+	// sets. Accessed and updated via its load and
+	// update methods. Not protected by a lock.
+	//
+	// Reset at mark termination.
+	// Used by mheap.nextSpanForSweep.
+	centralIndex sweepClass
+}
+
+// sweepClass is a spanClass and one bit to represent whether we're currently
+// sweeping partial or full spans.
+type sweepClass uint32
+
+const (
+	numSweepClasses            = numSpanClasses * 2
+	sweepClassDone  sweepClass = sweepClass(^uint32(0))
+)
+
+func (s *sweepClass) load() sweepClass {
+	return sweepClass(atomic.Load((*uint32)(s)))
+}
+
+func (s *sweepClass) update(sNew sweepClass) {
+	// Only update *s if its current value is less than sNew,
+	// since *s increases monotonically.
+	sOld := s.load()
+	for sOld < sNew && !atomic.Cas((*uint32)(s), uint32(sOld), uint32(sNew)) {
+		sOld = s.load()
+	}
+	// TODO(mknyszek): This isn't the only place we have
+	// an atomic monotonically increasing counter. It would
+	// be nice to have an "atomic max" which is just implemented
+	// as the above on most architectures. Some architectures
+	// like RISC-V however have native support for an atomic max.
+}
+
+func (s *sweepClass) clear() {
+	atomic.Store((*uint32)(s), 0)
+}
+
+// split returns the underlying span class as well as
+// whether we're interested in the full or partial
+// unswept lists for that class, indicated as a boolean
+// (true means "full").
+func (s sweepClass) split() (spc spanClass, full bool) {
+	return spanClass(s >> 1), s&1 == 0
+}
+
+// nextSpanForSweep finds and pops the next span for sweeping from the
+// central sweep buffers. It returns ownership of the span to the caller.
+// Returns nil if no such span exists.
+func (h *mheap) nextSpanForSweep() *mspan {
+	sg := h.sweepgen
+	for sc := sweep.centralIndex.load(); sc < numSweepClasses; sc++ {
+		spc, full := sc.split()
+		c := &h.central[spc].mcentral
+		var s *mspan
+		if full {
+			s = c.fullUnswept(sg).pop()
+		} else {
+			s = c.partialUnswept(sg).pop()
+		}
+		if s != nil {
+			// Write down that we found something so future sweepers
+			// can start from here.
+			sweep.centralIndex.update(sc)
+			return s
+		}
+	}
+	// Write down that we found nothing.
+	sweep.centralIndex.update(sweepClassDone)
+	return nil
+}
+
+const sweepDrainedMask = 1 << 31
+
+// activeSweep is a type that captures whether sweeping
+// is done, and whether there are any outstanding sweepers.
+//
+// Every potential sweeper must call begin() before they look
+// for work, and end() after they've finished sweeping.
+type activeSweep struct {
+	// state is divided into two parts.
+	//
+	// The top bit (masked by sweepDrainedMask) is a boolean
+	// value indicating whether all the sweep work has been
+	// drained from the queue.
+	//
+	// The rest of the bits are a counter, indicating the
+	// number of outstanding concurrent sweepers.
+	state atomic.Uint32
+}
+
+// begin registers a new sweeper. Returns a sweepLocker
+// for acquiring spans for sweeping. Any outstanding sweeper blocks
+// sweep termination.
+//
+// If the sweepLocker is invalid, the caller can be sure that all
+// outstanding sweep work has been drained, so there is nothing left
+// to sweep. Note that there may be sweepers currently running, so
+// this does not indicate that all sweeping has completed.
+//
+// Even if the sweepLocker is invalid, its sweepGen is always valid.
+func (a *activeSweep) begin() sweepLocker {
+	for {
+		state := a.state.Load()
+		if state&sweepDrainedMask != 0 {
+			return sweepLocker{mheap_.sweepgen, false}
+		}
+		if a.state.CompareAndSwap(state, state+1) {
+			return sweepLocker{mheap_.sweepgen, true}
+		}
+	}
+}
+
+// end deregisters a sweeper. Must be called once for each time
+// begin is called if the sweepLocker is valid.
+func (a *activeSweep) end(sl sweepLocker) {
+	if sl.sweepGen != mheap_.sweepgen {
+		throw("sweeper left outstanding across sweep generations")
+	}
+	for {
+		state := a.state.Load()
+		if (state&^sweepDrainedMask)-1 >= sweepDrainedMask {
+			throw("mismatched begin/end of activeSweep")
+		}
+		if a.state.CompareAndSwap(state, state-1) {
+			if state != sweepDrainedMask {
+				return
+			}
+			if debug.gcpacertrace > 0 {
+				print("pacer: sweep done at heap size ", gcController.heapLive>>20, "MB; allocated ", (gcController.heapLive-mheap_.sweepHeapLiveBasis)>>20, "MB during sweep; swept ", mheap_.pagesSwept.Load(), " pages at ", mheap_.sweepPagesPerByte, " pages/byte\n")
+			}
+			return
+		}
+	}
+}
+
+// markDrained marks the active sweep cycle as having drained
+// all remaining work. This is safe to be called concurrently
+// with all other methods of activeSweep, though may race.
+//
+// Returns true if this call was the one that actually performed
+// the mark.
+func (a *activeSweep) markDrained() bool {
+	for {
+		state := a.state.Load()
+		if state&sweepDrainedMask != 0 {
+			return false
+		}
+		if a.state.CompareAndSwap(state, state|sweepDrainedMask) {
+			return true
+		}
+	}
+}
+
+// sweepers returns the current number of active sweepers.
+func (a *activeSweep) sweepers() uint32 {
+	return a.state.Load() &^ sweepDrainedMask
+}
+
+// isDone returns true if all sweep work has been drained and no more
+// outstanding sweepers exist. That is, when the sweep phase is
+// completely done.
+func (a *activeSweep) isDone() bool {
+	return a.state.Load() == sweepDrainedMask
+}
+
+// reset sets up the activeSweep for the next sweep cycle.
+//
+// The world must be stopped.
+func (a *activeSweep) reset() {
+	assertWorldStopped()
+	a.state.Store(0)
+}
+
+// finishsweep_m ensures that all spans are swept.
+//
+// The world must be stopped. This ensures there are no sweeps in
+// progress.
+//
+//go:nowritebarrier
+func finishsweep_m() {
+	assertWorldStopped()
+
+	// Sweeping must be complete before marking commences, so
+	// sweep any unswept spans. If this is a concurrent GC, there
+	// shouldn't be any spans left to sweep, so this should finish
+	// instantly. If GC was forced before the concurrent sweep
+	// finished, there may be spans to sweep.
+	for sweepone() != ^uintptr(0) {
+		sweep.npausesweep++
+	}
+
+	// Make sure there aren't any outstanding sweepers left.
+	// At this point, with the world stopped, it means one of two
+	// things. Either we were able to preempt a sweeper, or that
+	// a sweeper didn't call sweep.active.end when it should have.
+	// Both cases indicate a bug, so throw.
+	if sweep.active.sweepers() != 0 {
+		throw("active sweepers found at start of mark phase")
+	}
+
+	// Reset all the unswept buffers, which should be empty.
+	// Do this in sweep termination as opposed to mark termination
+	// so that we can catch unswept spans and reclaim blocks as
+	// soon as possible.
+	sg := mheap_.sweepgen
+	for i := range mheap_.central {
+		c := &mheap_.central[i].mcentral
+		c.partialUnswept(sg).reset()
+		c.fullUnswept(sg).reset()
+	}
+
+	// Sweeping is done, so if the scavenger isn't already awake,
+	// wake it up. There's definitely work for it to do at this
+	// point.
+	scavenger.wake()
+
+	nextMarkBitArenaEpoch()
+}
+
+func bgsweep(c chan int) {
+	sweep.g = getg()
+
+	lockInit(&sweep.lock, lockRankSweep)
+	lock(&sweep.lock)
+	sweep.parked = true
+	c <- 1
+	goparkunlock(&sweep.lock, waitReasonGCSweepWait, traceEvGoBlock, 1)
+
+	for {
+		for sweepone() != ^uintptr(0) {
+			sweep.nbgsweep++
+			Gosched()
+		}
+		for freeSomeWbufs(true) {
+			Gosched()
+		}
+		lock(&sweep.lock)
+		if !isSweepDone() {
+			// This can happen if a GC runs between
+			// gosweepone returning ^0 above
+			// and the lock being acquired.
+			unlock(&sweep.lock)
+			continue
+		}
+		sweep.parked = true
+		goparkunlock(&sweep.lock, waitReasonGCSweepWait, traceEvGoBlock, 1)
+	}
+}
+
+// sweepLocker acquires sweep ownership of spans.
+type sweepLocker struct {
+	// sweepGen is the sweep generation of the heap.
+	sweepGen uint32
+	valid    bool
+}
+
+// sweepLocked represents sweep ownership of a span.
+type sweepLocked struct {
+	*mspan
+}
+
+// tryAcquire attempts to acquire sweep ownership of span s. If it
+// successfully acquires ownership, it blocks sweep completion.
+func (l *sweepLocker) tryAcquire(s *mspan) (sweepLocked, bool) {
+	if !l.valid {
+		throw("use of invalid sweepLocker")
+	}
+	// Check before attempting to CAS.
+	if atomic.Load(&s.sweepgen) != l.sweepGen-2 {
+		return sweepLocked{}, false
+	}
+	// Attempt to acquire sweep ownership of s.
+	if !atomic.Cas(&s.sweepgen, l.sweepGen-2, l.sweepGen-1) {
+		return sweepLocked{}, false
+	}
+	return sweepLocked{s}, true
+}
+
+// sweepone sweeps some unswept heap span and returns the number of pages returned
+// to the heap, or ^uintptr(0) if there was nothing to sweep.
+func sweepone() uintptr {
+	gp := getg()
+
+	// Increment locks to ensure that the goroutine is not preempted
+	// in the middle of sweep thus leaving the span in an inconsistent state for next GC
+	gp.m.locks++
+
+	// TODO(austin): sweepone is almost always called in a loop;
+	// lift the sweepLocker into its callers.
+	sl := sweep.active.begin()
+	if !sl.valid {
+		gp.m.locks--
+		return ^uintptr(0)
+	}
+
+	// Find a span to sweep.
+	npages := ^uintptr(0)
+	var noMoreWork bool
+	for {
+		s := mheap_.nextSpanForSweep()
+		if s == nil {
+			noMoreWork = sweep.active.markDrained()
+			break
+		}
+		if state := s.state.get(); state != mSpanInUse {
+			// This can happen if direct sweeping already
+			// swept this span, but in that case the sweep
+			// generation should always be up-to-date.
+			if !(s.sweepgen == sl.sweepGen || s.sweepgen == sl.sweepGen+3) {
+				print("runtime: bad span s.state=", state, " s.sweepgen=", s.sweepgen, " sweepgen=", sl.sweepGen, "\n")
+				throw("non in-use span in unswept list")
+			}
+			continue
+		}
+		if s, ok := sl.tryAcquire(s); ok {
+			// Sweep the span we found.
+			npages = s.npages
+			if s.sweep(false) {
+				// Whole span was freed. Count it toward the
+				// page reclaimer credit since these pages can
+				// now be used for span allocation.
+				mheap_.reclaimCredit.Add(npages)
+			} else {
+				// Span is still in-use, so this returned no
+				// pages to the heap and the span needs to
+				// move to the swept in-use list.
+				npages = 0
+			}
+			break
+		}
+	}
+	sweep.active.end(sl)
+
+	if noMoreWork {
+		// The sweep list is empty. There may still be
+		// concurrent sweeps running, but we're at least very
+		// close to done sweeping.
+
+		// Move the scavenge gen forward (signaling
+		// that there's new work to do) and wake the scavenger.
+		//
+		// The scavenger is signaled by the last sweeper because once
+		// sweeping is done, we will definitely have useful work for
+		// the scavenger to do, since the scavenger only runs over the
+		// heap once per GC cycle. This update is not done during sweep
+		// termination because in some cases there may be a long delay
+		// between sweep done and sweep termination (e.g. not enough
+		// allocations to trigger a GC) which would be nice to fill in
+		// with scavenging work.
+		if debug.scavtrace > 0 {
+			systemstack(func() {
+				lock(&mheap_.lock)
+				released := atomic.Loaduintptr(&mheap_.pages.scav.released)
+				printScavTrace(released, false)
+				atomic.Storeuintptr(&mheap_.pages.scav.released, 0)
+				unlock(&mheap_.lock)
+			})
+		}
+		scavenger.ready()
+	}
+
+	gp.m.locks--
+	return npages
+}
+
+// isSweepDone reports whether all spans are swept.
+//
+// Note that this condition may transition from false to true at any
+// time as the sweeper runs. It may transition from true to false if a
+// GC runs; to prevent that the caller must be non-preemptible or must
+// somehow block GC progress.
+func isSweepDone() bool {
+	return sweep.active.isDone()
+}
+
+// Returns only when span s has been swept.
+//
+//go:nowritebarrier
+func (s *mspan) ensureSwept() {
+	// Caller must disable preemption.
+	// Otherwise when this function returns the span can become unswept again
+	// (if GC is triggered on another goroutine).
+	_g_ := getg()
+	if _g_.m.locks == 0 && _g_.m.mallocing == 0 && _g_ != _g_.m.g0 {
+		throw("mspan.ensureSwept: m is not locked")
+	}
+
+	// If this operation fails, then that means that there are
+	// no more spans to be swept. In this case, either s has already
+	// been swept, or is about to be acquired for sweeping and swept.
+	sl := sweep.active.begin()
+	if sl.valid {
+		// The caller must be sure that the span is a mSpanInUse span.
+		if s, ok := sl.tryAcquire(s); ok {
+			s.sweep(false)
+			sweep.active.end(sl)
+			return
+		}
+		sweep.active.end(sl)
+	}
+
+	// Unfortunately we can't sweep the span ourselves. Somebody else
+	// got to it first. We don't have efficient means to wait, but that's
+	// OK, it will be swept fairly soon.
+	for {
+		spangen := atomic.Load(&s.sweepgen)
+		if spangen == sl.sweepGen || spangen == sl.sweepGen+3 {
+			break
+		}
+		osyield()
+	}
+}
+
+// Sweep frees or collects finalizers for blocks not marked in the mark phase.
+// It clears the mark bits in preparation for the next GC round.
+// Returns true if the span was returned to heap.
+// If preserve=true, don't return it to heap nor relink in mcentral lists;
+// caller takes care of it.
+func (sl *sweepLocked) sweep(preserve bool) bool {
+	// It's critical that we enter this function with preemption disabled,
+	// GC must not start while we are in the middle of this function.
+	_g_ := getg()
+	if _g_.m.locks == 0 && _g_.m.mallocing == 0 && _g_ != _g_.m.g0 {
+		throw("mspan.sweep: m is not locked")
+	}
+
+	s := sl.mspan
+	if !preserve {
+		// We'll release ownership of this span. Nil it out to
+		// prevent the caller from accidentally using it.
+		sl.mspan = nil
+	}
+
+	sweepgen := mheap_.sweepgen
+	if state := s.state.get(); state != mSpanInUse || s.sweepgen != sweepgen-1 {
+		print("mspan.sweep: state=", state, " sweepgen=", s.sweepgen, " mheap.sweepgen=", sweepgen, "\n")
+		throw("mspan.sweep: bad span state")
+	}
+
+	if trace.enabled {
+		traceGCSweepSpan(s.npages * _PageSize)
+	}
+
+	mheap_.pagesSwept.Add(int64(s.npages))
+
+	spc := s.spanclass
+	size := s.elemsize
+
+	// The allocBits indicate which unmarked objects don't need to be
+	// processed since they were free at the end of the last GC cycle
+	// and were not allocated since then.
+	// If the allocBits index is >= s.freeindex and the bit
+	// is not marked then the object remains unallocated
+	// since the last GC.
+	// This situation is analogous to being on a freelist.
+
+	// Unlink & free special records for any objects we're about to free.
+	// Two complications here:
+	// 1. An object can have both finalizer and profile special records.
+	//    In such case we need to queue finalizer for execution,
+	//    mark the object as live and preserve the profile special.
+	// 2. A tiny object can have several finalizers setup for different offsets.
+	//    If such object is not marked, we need to queue all finalizers at once.
+	// Both 1 and 2 are possible at the same time.
+	hadSpecials := s.specials != nil
+	siter := newSpecialsIter(s)
+	for siter.valid() {
+		// A finalizer can be set for an inner byte of an object, find object beginning.
+		objIndex := uintptr(siter.s.offset) / size
+		p := s.base() + objIndex*size
+		mbits := s.markBitsForIndex(objIndex)
+		if !mbits.isMarked() {
+			// This object is not marked and has at least one special record.
+			// Pass 1: see if it has at least one finalizer.
+			hasFin := false
+			endOffset := p - s.base() + size
+			for tmp := siter.s; tmp != nil && uintptr(tmp.offset) < endOffset; tmp = tmp.next {
+				if tmp.kind == _KindSpecialFinalizer {
+					// Stop freeing of object if it has a finalizer.
+					mbits.setMarkedNonAtomic()
+					hasFin = true
+					break
+				}
+			}
+			// Pass 2: queue all finalizers _or_ handle profile record.
+			for siter.valid() && uintptr(siter.s.offset) < endOffset {
+				// Find the exact byte for which the special was setup
+				// (as opposed to object beginning).
+				special := siter.s
+				p := s.base() + uintptr(special.offset)
+				if special.kind == _KindSpecialFinalizer || !hasFin {
+					siter.unlinkAndNext()
+					freeSpecial(special, unsafe.Pointer(p), size)
+				} else {
+					// The object has finalizers, so we're keeping it alive.
+					// All other specials only apply when an object is freed,
+					// so just keep the special record.
+					siter.next()
+				}
+			}
+		} else {
+			// object is still live
+			if siter.s.kind == _KindSpecialReachable {
+				special := siter.unlinkAndNext()
+				(*specialReachable)(unsafe.Pointer(special)).reachable = true
+				freeSpecial(special, unsafe.Pointer(p), size)
+			} else {
+				// keep special record
+				siter.next()
+			}
+		}
+	}
+	if hadSpecials && s.specials == nil {
+		spanHasNoSpecials(s)
+	}
+
+	if debug.allocfreetrace != 0 || debug.clobberfree != 0 || raceenabled || msanenabled || asanenabled {
+		// Find all newly freed objects. This doesn't have to
+		// efficient; allocfreetrace has massive overhead.
+		mbits := s.markBitsForBase()
+		abits := s.allocBitsForIndex(0)
+		for i := uintptr(0); i < s.nelems; i++ {
+			if !mbits.isMarked() && (abits.index < s.freeindex || abits.isMarked()) {
+				x := s.base() + i*s.elemsize
+				if debug.allocfreetrace != 0 {
+					tracefree(unsafe.Pointer(x), size)
+				}
+				if debug.clobberfree != 0 {
+					clobberfree(unsafe.Pointer(x), size)
+				}
+				if raceenabled {
+					racefree(unsafe.Pointer(x), size)
+				}
+				if msanenabled {
+					msanfree(unsafe.Pointer(x), size)
+				}
+				if asanenabled {
+					asanpoison(unsafe.Pointer(x), size)
+				}
+			}
+			mbits.advance()
+			abits.advance()
+		}
+	}
+
+	// Check for zombie objects.
+	if s.freeindex < s.nelems {
+		// Everything < freeindex is allocated and hence
+		// cannot be zombies.
+		//
+		// Check the first bitmap byte, where we have to be
+		// careful with freeindex.
+		obj := s.freeindex
+		if (*s.gcmarkBits.bytep(obj / 8)&^*s.allocBits.bytep(obj / 8))>>(obj%8) != 0 {
+			s.reportZombies()
+		}
+		// Check remaining bytes.
+		for i := obj/8 + 1; i < divRoundUp(s.nelems, 8); i++ {
+			if *s.gcmarkBits.bytep(i)&^*s.allocBits.bytep(i) != 0 {
+				s.reportZombies()
+			}
+		}
+	}
+
+	// Count the number of free objects in this span.
+	nalloc := uint16(s.countAlloc())
+	nfreed := s.allocCount - nalloc
+	if nalloc > s.allocCount {
+		// The zombie check above should have caught this in
+		// more detail.
+		print("runtime: nelems=", s.nelems, " nalloc=", nalloc, " previous allocCount=", s.allocCount, " nfreed=", nfreed, "\n")
+		throw("sweep increased allocation count")
+	}
+
+	s.allocCount = nalloc
+	s.freeindex = 0 // reset allocation index to start of span.
+	if trace.enabled {
+		getg().m.p.ptr().traceReclaimed += uintptr(nfreed) * s.elemsize
+	}
+
+	// gcmarkBits becomes the allocBits.
+	// get a fresh cleared gcmarkBits in preparation for next GC
+	s.allocBits = s.gcmarkBits
+	s.gcmarkBits = newMarkBits(s.nelems)
+
+	// Initialize alloc bits cache.
+	s.refillAllocCache(0)
+
+	// The span must be in our exclusive ownership until we update sweepgen,
+	// check for potential races.
+	if state := s.state.get(); state != mSpanInUse || s.sweepgen != sweepgen-1 {
+		print("mspan.sweep: state=", state, " sweepgen=", s.sweepgen, " mheap.sweepgen=", sweepgen, "\n")
+		throw("mspan.sweep: bad span state after sweep")
+	}
+	if s.sweepgen == sweepgen+1 || s.sweepgen == sweepgen+3 {
+		throw("swept cached span")
+	}
+
+	// We need to set s.sweepgen = h.sweepgen only when all blocks are swept,
+	// because of the potential for a concurrent free/SetFinalizer.
+	//
+	// But we need to set it before we make the span available for allocation
+	// (return it to heap or mcentral), because allocation code assumes that a
+	// span is already swept if available for allocation.
+	//
+	// Serialization point.
+	// At this point the mark bits are cleared and allocation ready
+	// to go so release the span.
+	atomic.Store(&s.sweepgen, sweepgen)
+
+	if spc.sizeclass() != 0 {
+		// Handle spans for small objects.
+		if nfreed > 0 {
+			// Only mark the span as needing zeroing if we've freed any
+			// objects, because a fresh span that had been allocated into,
+			// wasn't totally filled, but then swept, still has all of its
+			// free slots zeroed.
+			s.needzero = 1
+			stats := memstats.heapStats.acquire()
+			atomic.Xadd64(&stats.smallFreeCount[spc.sizeclass()], int64(nfreed))
+			memstats.heapStats.release()
+
+			// Count the frees in the inconsistent, internal stats.
+			gcController.totalFree.Add(int64(nfreed) * int64(s.elemsize))
+		}
+		if !preserve {
+			// The caller may not have removed this span from whatever
+			// unswept set its on but taken ownership of the span for
+			// sweeping by updating sweepgen. If this span still is in
+			// an unswept set, then the mcentral will pop it off the
+			// set, check its sweepgen, and ignore it.
+			if nalloc == 0 {
+				// Free totally free span directly back to the heap.
+				mheap_.freeSpan(s)
+				return true
+			}
+			// Return span back to the right mcentral list.
+			if uintptr(nalloc) == s.nelems {
+				mheap_.central[spc].mcentral.fullSwept(sweepgen).push(s)
+			} else {
+				mheap_.central[spc].mcentral.partialSwept(sweepgen).push(s)
+			}
+		}
+	} else if !preserve {
+		// Handle spans for large objects.
+		if nfreed != 0 {
+			// Free large object span to heap.
+
+			// NOTE(rsc,dvyukov): The original implementation of efence
+			// in CL 22060046 used sysFree instead of sysFault, so that
+			// the operating system would eventually give the memory
+			// back to us again, so that an efence program could run
+			// longer without running out of memory. Unfortunately,
+			// calling sysFree here without any kind of adjustment of the
+			// heap data structures means that when the memory does
+			// come back to us, we have the wrong metadata for it, either in
+			// the mspan structures or in the garbage collection bitmap.
+			// Using sysFault here means that the program will run out of
+			// memory fairly quickly in efence mode, but at least it won't
+			// have mysterious crashes due to confused memory reuse.
+			// It should be possible to switch back to sysFree if we also
+			// implement and then call some kind of mheap.deleteSpan.
+			if debug.efence > 0 {
+				s.limit = 0 // prevent mlookup from finding this span
+				sysFault(unsafe.Pointer(s.base()), size)
+			} else {
+				mheap_.freeSpan(s)
+			}
+
+			// Count the free in the consistent, external stats.
+			stats := memstats.heapStats.acquire()
+			atomic.Xadd64(&stats.largeFreeCount, 1)
+			atomic.Xadd64(&stats.largeFree, int64(size))
+			memstats.heapStats.release()
+
+			// Count the free in the inconsistent, internal stats.
+			gcController.totalFree.Add(int64(size))
+
+			return true
+		}
+
+		// Add a large span directly onto the full+swept list.
+		mheap_.central[spc].mcentral.fullSwept(sweepgen).push(s)
+	}
+	return false
+}
+
+// reportZombies reports any marked but free objects in s and throws.
+//
+// This generally means one of the following:
+//
+// 1. User code converted a pointer to a uintptr and then back
+// unsafely, and a GC ran while the uintptr was the only reference to
+// an object.
+//
+// 2. User code (or a compiler bug) constructed a bad pointer that
+// points to a free slot, often a past-the-end pointer.
+//
+// 3. The GC two cycles ago missed a pointer and freed a live object,
+// but it was still live in the last cycle, so this GC cycle found a
+// pointer to that object and marked it.
+func (s *mspan) reportZombies() {
+	printlock()
+	print("runtime: marked free object in span ", s, ", elemsize=", s.elemsize, " freeindex=", s.freeindex, " (bad use of unsafe.Pointer? try -d=checkptr)\n")
+	mbits := s.markBitsForBase()
+	abits := s.allocBitsForIndex(0)
+	for i := uintptr(0); i < s.nelems; i++ {
+		addr := s.base() + i*s.elemsize
+		print(hex(addr))
+		alloc := i < s.freeindex || abits.isMarked()
+		if alloc {
+			print(" alloc")
+		} else {
+			print(" free ")
+		}
+		if mbits.isMarked() {
+			print(" marked  ")
+		} else {
+			print(" unmarked")
+		}
+		zombie := mbits.isMarked() && !alloc
+		if zombie {
+			print(" zombie")
+		}
+		print("\n")
+		if zombie {
+			length := s.elemsize
+			if length > 1024 {
+				length = 1024
+			}
+			hexdumpWords(addr, addr+length, nil)
+		}
+		mbits.advance()
+		abits.advance()
+	}
+	throw("found pointer to free object")
+}
+
+// deductSweepCredit deducts sweep credit for allocating a span of
+// size spanBytes. This must be performed *before* the span is
+// allocated to ensure the system has enough credit. If necessary, it
+// performs sweeping to prevent going in to debt. If the caller will
+// also sweep pages (e.g., for a large allocation), it can pass a
+// non-zero callerSweepPages to leave that many pages unswept.
+//
+// deductSweepCredit makes a worst-case assumption that all spanBytes
+// bytes of the ultimately allocated span will be available for object
+// allocation.
+//
+// deductSweepCredit is the core of the "proportional sweep" system.
+// It uses statistics gathered by the garbage collector to perform
+// enough sweeping so that all pages are swept during the concurrent
+// sweep phase between GC cycles.
+//
+// mheap_ must NOT be locked.
+func deductSweepCredit(spanBytes uintptr, callerSweepPages uintptr) {
+	if mheap_.sweepPagesPerByte == 0 {
+		// Proportional sweep is done or disabled.
+		return
+	}
+
+	if trace.enabled {
+		traceGCSweepStart()
+	}
+
+retry:
+	sweptBasis := mheap_.pagesSweptBasis.Load()
+
+	// Fix debt if necessary.
+	newHeapLive := uintptr(atomic.Load64(&gcController.heapLive)-mheap_.sweepHeapLiveBasis) + spanBytes
+	pagesTarget := int64(mheap_.sweepPagesPerByte*float64(newHeapLive)) - int64(callerSweepPages)
+	for pagesTarget > int64(mheap_.pagesSwept.Load()-sweptBasis) {
+		if sweepone() == ^uintptr(0) {
+			mheap_.sweepPagesPerByte = 0
+			break
+		}
+		if mheap_.pagesSweptBasis.Load() != sweptBasis {
+			// Sweep pacing changed. Recompute debt.
+			goto retry
+		}
+	}
+
+	if trace.enabled {
+		traceGCSweepDone()
+	}
+}
+
+// clobberfree sets the memory content at x to bad content, for debugging
+// purposes.
+func clobberfree(x unsafe.Pointer, size uintptr) {
+	// size (span.elemsize) is always a multiple of 4.
+	for i := uintptr(0); i < size; i += 4 {
+		*(*uint32)(add(x, i)) = 0xdeadbeef
+	}
+}
+
+// gcPaceSweeper updates the sweeper's pacing parameters.
+//
+// Must be called whenever the GC's pacing is updated.
+//
+// The world must be stopped, or mheap_.lock must be held.
+func gcPaceSweeper(trigger uint64) {
+	assertWorldStoppedOrLockHeld(&mheap_.lock)
+
+	// Update sweep pacing.
+	if isSweepDone() {
+		mheap_.sweepPagesPerByte = 0
+	} else {
+		// Concurrent sweep needs to sweep all of the in-use
+		// pages by the time the allocated heap reaches the GC
+		// trigger. Compute the ratio of in-use pages to sweep
+		// per byte allocated, accounting for the fact that
+		// some might already be swept.
+		heapLiveBasis := atomic.Load64(&gcController.heapLive)
+		heapDistance := int64(trigger) - int64(heapLiveBasis)
+		// Add a little margin so rounding errors and
+		// concurrent sweep are less likely to leave pages
+		// unswept when GC starts.
+		heapDistance -= 1024 * 1024
+		if heapDistance < _PageSize {
+			// Avoid setting the sweep ratio extremely high
+			heapDistance = _PageSize
+		}
+		pagesSwept := mheap_.pagesSwept.Load()
+		pagesInUse := mheap_.pagesInUse.Load()
+		sweepDistancePages := int64(pagesInUse) - int64(pagesSwept)
+		if sweepDistancePages <= 0 {
+			mheap_.sweepPagesPerByte = 0
+		} else {
+			mheap_.sweepPagesPerByte = float64(sweepDistancePages) / float64(heapDistance)
+			mheap_.sweepHeapLiveBasis = heapLiveBasis
+			// Write pagesSweptBasis last, since this
+			// signals concurrent sweeps to recompute
+			// their debt.
+			mheap_.pagesSweptBasis.Store(pagesSwept)
+		}
+	}
+}
diff --git a/contrib/go/_std_1.19/src/runtime/mgcwork.go b/contrib/go/_std_1.19/src/runtime/mgcwork.go
new file mode 100644
index 0000000000..424de2fcca
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/mgcwork.go
@@ -0,0 +1,488 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"internal/goarch"
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+const (
+	_WorkbufSize = 2048 // in bytes; larger values result in less contention
+
+	// workbufAlloc is the number of bytes to allocate at a time
+	// for new workbufs. This must be a multiple of pageSize and
+	// should be a multiple of _WorkbufSize.
+	//
+	// Larger values reduce workbuf allocation overhead. Smaller
+	// values reduce heap fragmentation.
+	workbufAlloc = 32 << 10
+)
+
+func init() {
+	if workbufAlloc%pageSize != 0 || workbufAlloc%_WorkbufSize != 0 {
+		throw("bad workbufAlloc")
+	}
+}
+
+// Garbage collector work pool abstraction.
+//
+// This implements a producer/consumer model for pointers to grey
+// objects. A grey object is one that is marked and on a work
+// queue. A black object is marked and not on a work queue.
+//
+// Write barriers, root discovery, stack scanning, and object scanning
+// produce pointers to grey objects. Scanning consumes pointers to
+// grey objects, thus blackening them, and then scans them,
+// potentially producing new pointers to grey objects.
+
+// A gcWork provides the interface to produce and consume work for the
+// garbage collector.
+//
+// A gcWork can be used on the stack as follows:
+//
+//	(preemption must be disabled)
+//	gcw := &getg().m.p.ptr().gcw
+//	.. call gcw.put() to produce and gcw.tryGet() to consume ..
+//
+// It's important that any use of gcWork during the mark phase prevent
+// the garbage collector from transitioning to mark termination since
+// gcWork may locally hold GC work buffers. This can be done by
+// disabling preemption (systemstack or acquirem).
+type gcWork struct {
+	// wbuf1 and wbuf2 are the primary and secondary work buffers.
+	//
+	// This can be thought of as a stack of both work buffers'
+	// pointers concatenated. When we pop the last pointer, we
+	// shift the stack up by one work buffer by bringing in a new
+	// full buffer and discarding an empty one. When we fill both
+	// buffers, we shift the stack down by one work buffer by
+	// bringing in a new empty buffer and discarding a full one.
+	// This way we have one buffer's worth of hysteresis, which
+	// amortizes the cost of getting or putting a work buffer over
+	// at least one buffer of work and reduces contention on the
+	// global work lists.
+	//
+	// wbuf1 is always the buffer we're currently pushing to and
+	// popping from and wbuf2 is the buffer that will be discarded
+	// next.
+	//
+	// Invariant: Both wbuf1 and wbuf2 are nil or neither are.
+	wbuf1, wbuf2 *workbuf
+
+	// Bytes marked (blackened) on this gcWork. This is aggregated
+	// into work.bytesMarked by dispose.
+	bytesMarked uint64
+
+	// Heap scan work performed on this gcWork. This is aggregated into
+	// gcController by dispose and may also be flushed by callers.
+	// Other types of scan work are flushed immediately.
+	heapScanWork int64
+
+	// flushedWork indicates that a non-empty work buffer was
+	// flushed to the global work list since the last gcMarkDone
+	// termination check. Specifically, this indicates that this
+	// gcWork may have communicated work to another gcWork.
+	flushedWork bool
+}
+
+// Most of the methods of gcWork are go:nowritebarrierrec because the
+// write barrier itself can invoke gcWork methods but the methods are
+// not generally re-entrant. Hence, if a gcWork method invoked the
+// write barrier while the gcWork was in an inconsistent state, and
+// the write barrier in turn invoked a gcWork method, it could
+// permanently corrupt the gcWork.
+
+func (w *gcWork) init() {
+	w.wbuf1 = getempty()
+	wbuf2 := trygetfull()
+	if wbuf2 == nil {
+		wbuf2 = getempty()
+	}
+	w.wbuf2 = wbuf2
+}
+
+// put enqueues a pointer for the garbage collector to trace.
+// obj must point to the beginning of a heap object or an oblet.
+//
+//go:nowritebarrierrec
+func (w *gcWork) put(obj uintptr) {
+	flushed := false
+	wbuf := w.wbuf1
+	// Record that this may acquire the wbufSpans or heap lock to
+	// allocate a workbuf.
+	lockWithRankMayAcquire(&work.wbufSpans.lock, lockRankWbufSpans)
+	lockWithRankMayAcquire(&mheap_.lock, lockRankMheap)
+	if wbuf == nil {
+		w.init()
+		wbuf = w.wbuf1
+		// wbuf is empty at this point.
+	} else if wbuf.nobj == len(wbuf.obj) {
+		w.wbuf1, w.wbuf2 = w.wbuf2, w.wbuf1
+		wbuf = w.wbuf1
+		if wbuf.nobj == len(wbuf.obj) {
+			putfull(wbuf)
+			w.flushedWork = true
+			wbuf = getempty()
+			w.wbuf1 = wbuf
+			flushed = true
+		}
+	}
+
+	wbuf.obj[wbuf.nobj] = obj
+	wbuf.nobj++
+
+	// If we put a buffer on full, let the GC controller know so
+	// it can encourage more workers to run. We delay this until
+	// the end of put so that w is in a consistent state, since
+	// enlistWorker may itself manipulate w.
+	if flushed && gcphase == _GCmark {
+		gcController.enlistWorker()
+	}
+}
+
+// putFast does a put and reports whether it can be done quickly
+// otherwise it returns false and the caller needs to call put.
+//
+//go:nowritebarrierrec
+func (w *gcWork) putFast(obj uintptr) bool {
+	wbuf := w.wbuf1
+	if wbuf == nil || wbuf.nobj == len(wbuf.obj) {
+		return false
+	}
+
+	wbuf.obj[wbuf.nobj] = obj
+	wbuf.nobj++
+	return true
+}
+
+// putBatch performs a put on every pointer in obj. See put for
+// constraints on these pointers.
+//
+//go:nowritebarrierrec
+func (w *gcWork) putBatch(obj []uintptr) {
+	if len(obj) == 0 {
+		return
+	}
+
+	flushed := false
+	wbuf := w.wbuf1
+	if wbuf == nil {
+		w.init()
+		wbuf = w.wbuf1
+	}
+
+	for len(obj) > 0 {
+		for wbuf.nobj == len(wbuf.obj) {
+			putfull(wbuf)
+			w.flushedWork = true
+			w.wbuf1, w.wbuf2 = w.wbuf2, getempty()
+			wbuf = w.wbuf1
+			flushed = true
+		}
+		n := copy(wbuf.obj[wbuf.nobj:], obj)
+		wbuf.nobj += n
+		obj = obj[n:]
+	}
+
+	if flushed && gcphase == _GCmark {
+		gcController.enlistWorker()
+	}
+}
+
+// tryGet dequeues a pointer for the garbage collector to trace.
+//
+// If there are no pointers remaining in this gcWork or in the global
+// queue, tryGet returns 0.  Note that there may still be pointers in
+// other gcWork instances or other caches.
+//
+//go:nowritebarrierrec
+func (w *gcWork) tryGet() uintptr {
+	wbuf := w.wbuf1
+	if wbuf == nil {
+		w.init()
+		wbuf = w.wbuf1
+		// wbuf is empty at this point.
+	}
+	if wbuf.nobj == 0 {
+		w.wbuf1, w.wbuf2 = w.wbuf2, w.wbuf1
+		wbuf = w.wbuf1
+		if wbuf.nobj == 0 {
+			owbuf := wbuf
+			wbuf = trygetfull()
+			if wbuf == nil {
+				return 0
+			}
+			putempty(owbuf)
+			w.wbuf1 = wbuf
+		}
+	}
+
+	wbuf.nobj--
+	return wbuf.obj[wbuf.nobj]
+}
+
+// tryGetFast dequeues a pointer for the garbage collector to trace
+// if one is readily available. Otherwise it returns 0 and
+// the caller is expected to call tryGet().
+//
+//go:nowritebarrierrec
+func (w *gcWork) tryGetFast() uintptr {
+	wbuf := w.wbuf1
+	if wbuf == nil || wbuf.nobj == 0 {
+		return 0
+	}
+
+	wbuf.nobj--
+	return wbuf.obj[wbuf.nobj]
+}
+
+// dispose returns any cached pointers to the global queue.
+// The buffers are being put on the full queue so that the
+// write barriers will not simply reacquire them before the
+// GC can inspect them. This helps reduce the mutator's
+// ability to hide pointers during the concurrent mark phase.
+//
+//go:nowritebarrierrec
+func (w *gcWork) dispose() {
+	if wbuf := w.wbuf1; wbuf != nil {
+		if wbuf.nobj == 0 {
+			putempty(wbuf)
+		} else {
+			putfull(wbuf)
+			w.flushedWork = true
+		}
+		w.wbuf1 = nil
+
+		wbuf = w.wbuf2
+		if wbuf.nobj == 0 {
+			putempty(wbuf)
+		} else {
+			putfull(wbuf)
+			w.flushedWork = true
+		}
+		w.wbuf2 = nil
+	}
+	if w.bytesMarked != 0 {
+		// dispose happens relatively infrequently. If this
+		// atomic becomes a problem, we should first try to
+		// dispose less and if necessary aggregate in a per-P
+		// counter.
+		atomic.Xadd64(&work.bytesMarked, int64(w.bytesMarked))
+		w.bytesMarked = 0
+	}
+	if w.heapScanWork != 0 {
+		gcController.heapScanWork.Add(w.heapScanWork)
+		w.heapScanWork = 0
+	}
+}
+
+// balance moves some work that's cached in this gcWork back on the
+// global queue.
+//
+//go:nowritebarrierrec
+func (w *gcWork) balance() {
+	if w.wbuf1 == nil {
+		return
+	}
+	if wbuf := w.wbuf2; wbuf.nobj != 0 {
+		putfull(wbuf)
+		w.flushedWork = true
+		w.wbuf2 = getempty()
+	} else if wbuf := w.wbuf1; wbuf.nobj > 4 {
+		w.wbuf1 = handoff(wbuf)
+		w.flushedWork = true // handoff did putfull
+	} else {
+		return
+	}
+	// We flushed a buffer to the full list, so wake a worker.
+	if gcphase == _GCmark {
+		gcController.enlistWorker()
+	}
+}
+
+// empty reports whether w has no mark work available.
+//
+//go:nowritebarrierrec
+func (w *gcWork) empty() bool {
+	return w.wbuf1 == nil || (w.wbuf1.nobj == 0 && w.wbuf2.nobj == 0)
+}
+
+// Internally, the GC work pool is kept in arrays in work buffers.
+// The gcWork interface caches a work buffer until full (or empty) to
+// avoid contending on the global work buffer lists.
+
+type workbufhdr struct {
+	node lfnode // must be first
+	nobj int
+}
+
+//go:notinheap
+type workbuf struct {
+	workbufhdr
+	// account for the above fields
+	obj [(_WorkbufSize - unsafe.Sizeof(workbufhdr{})) / goarch.PtrSize]uintptr
+}
+
+// workbuf factory routines. These funcs are used to manage the
+// workbufs.
+// If the GC asks for some work these are the only routines that
+// make wbufs available to the GC.
+
+func (b *workbuf) checknonempty() {
+	if b.nobj == 0 {
+		throw("workbuf is empty")
+	}
+}
+
+func (b *workbuf) checkempty() {
+	if b.nobj != 0 {
+		throw("workbuf is not empty")
+	}
+}
+
+// getempty pops an empty work buffer off the work.empty list,
+// allocating new buffers if none are available.
+//
+//go:nowritebarrier
+func getempty() *workbuf {
+	var b *workbuf
+	if work.empty != 0 {
+		b = (*workbuf)(work.empty.pop())
+		if b != nil {
+			b.checkempty()
+		}
+	}
+	// Record that this may acquire the wbufSpans or heap lock to
+	// allocate a workbuf.
+	lockWithRankMayAcquire(&work.wbufSpans.lock, lockRankWbufSpans)
+	lockWithRankMayAcquire(&mheap_.lock, lockRankMheap)
+	if b == nil {
+		// Allocate more workbufs.
+		var s *mspan
+		if work.wbufSpans.free.first != nil {
+			lock(&work.wbufSpans.lock)
+			s = work.wbufSpans.free.first
+			if s != nil {
+				work.wbufSpans.free.remove(s)
+				work.wbufSpans.busy.insert(s)
+			}
+			unlock(&work.wbufSpans.lock)
+		}
+		if s == nil {
+			systemstack(func() {
+				s = mheap_.allocManual(workbufAlloc/pageSize, spanAllocWorkBuf)
+			})
+			if s == nil {
+				throw("out of memory")
+			}
+			// Record the new span in the busy list.
+			lock(&work.wbufSpans.lock)
+			work.wbufSpans.busy.insert(s)
+			unlock(&work.wbufSpans.lock)
+		}
+		// Slice up the span into new workbufs. Return one and
+		// put the rest on the empty list.
+		for i := uintptr(0); i+_WorkbufSize <= workbufAlloc; i += _WorkbufSize {
+			newb := (*workbuf)(unsafe.Pointer(s.base() + i))
+			newb.nobj = 0
+			lfnodeValidate(&newb.node)
+			if i == 0 {
+				b = newb
+			} else {
+				putempty(newb)
+			}
+		}
+	}
+	return b
+}
+
+// putempty puts a workbuf onto the work.empty list.
+// Upon entry this goroutine owns b. The lfstack.push relinquishes ownership.
+//
+//go:nowritebarrier
+func putempty(b *workbuf) {
+	b.checkempty()
+	work.empty.push(&b.node)
+}
+
+// putfull puts the workbuf on the work.full list for the GC.
+// putfull accepts partially full buffers so the GC can avoid competing
+// with the mutators for ownership of partially full buffers.
+//
+//go:nowritebarrier
+func putfull(b *workbuf) {
+	b.checknonempty()
+	work.full.push(&b.node)
+}
+
+// trygetfull tries to get a full or partially empty workbuffer.
+// If one is not immediately available return nil
+//
+//go:nowritebarrier
+func trygetfull() *workbuf {
+	b := (*workbuf)(work.full.pop())
+	if b != nil {
+		b.checknonempty()
+		return b
+	}
+	return b
+}
+
+//go:nowritebarrier
+func handoff(b *workbuf) *workbuf {
+	// Make new buffer with half of b's pointers.
+	b1 := getempty()
+	n := b.nobj / 2
+	b.nobj -= n
+	b1.nobj = n
+	memmove(unsafe.Pointer(&b1.obj[0]), unsafe.Pointer(&b.obj[b.nobj]), uintptr(n)*unsafe.Sizeof(b1.obj[0]))
+
+	// Put b on full list - let first half of b get stolen.
+	putfull(b)
+	return b1
+}
+
+// prepareFreeWorkbufs moves busy workbuf spans to free list so they
+// can be freed to the heap. This must only be called when all
+// workbufs are on the empty list.
+func prepareFreeWorkbufs() {
+	lock(&work.wbufSpans.lock)
+	if work.full != 0 {
+		throw("cannot free workbufs when work.full != 0")
+	}
+	// Since all workbufs are on the empty list, we don't care
+	// which ones are in which spans. We can wipe the entire empty
+	// list and move all workbuf spans to the free list.
+	work.empty = 0
+	work.wbufSpans.free.takeAll(&work.wbufSpans.busy)
+	unlock(&work.wbufSpans.lock)
+}
+
+// freeSomeWbufs frees some workbufs back to the heap and returns
+// true if it should be called again to free more.
+func freeSomeWbufs(preemptible bool) bool {
+	const batchSize = 64 // ~1–2 µs per span.
+	lock(&work.wbufSpans.lock)
+	if gcphase != _GCoff || work.wbufSpans.free.isEmpty() {
+		unlock(&work.wbufSpans.lock)
+		return false
+	}
+	systemstack(func() {
+		gp := getg().m.curg
+		for i := 0; i < batchSize && !(preemptible && gp.preempt); i++ {
+			span := work.wbufSpans.free.first
+			if span == nil {
+				break
+			}
+			work.wbufSpans.free.remove(span)
+			mheap_.freeManual(span, spanAllocWorkBuf)
+		}
+	})
+	more := !work.wbufSpans.free.isEmpty()
+	unlock(&work.wbufSpans.lock)
+	return more
+}
diff --git a/contrib/go/_std_1.19/src/runtime/mheap.go b/contrib/go/_std_1.19/src/runtime/mheap.go
new file mode 100644
index 0000000000..b19a2ff408
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/mheap.go
@@ -0,0 +1,2156 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Page heap.
+//
+// See malloc.go for overview.
+
+package runtime
+
+import (
+	"internal/cpu"
+	"internal/goarch"
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+const (
+	// minPhysPageSize is a lower-bound on the physical page size. The
+	// true physical page size may be larger than this. In contrast,
+	// sys.PhysPageSize is an upper-bound on the physical page size.
+	minPhysPageSize = 4096
+
+	// maxPhysPageSize is the maximum page size the runtime supports.
+	maxPhysPageSize = 512 << 10
+
+	// maxPhysHugePageSize sets an upper-bound on the maximum huge page size
+	// that the runtime supports.
+	maxPhysHugePageSize = pallocChunkBytes
+
+	// pagesPerReclaimerChunk indicates how many pages to scan from the
+	// pageInUse bitmap at a time. Used by the page reclaimer.
+	//
+	// Higher values reduce contention on scanning indexes (such as
+	// h.reclaimIndex), but increase the minimum latency of the
+	// operation.
+	//
+	// The time required to scan this many pages can vary a lot depending
+	// on how many spans are actually freed. Experimentally, it can
+	// scan for pages at ~300 GB/ms on a 2.6GHz Core i7, but can only
+	// free spans at ~32 MB/ms. Using 512 pages bounds this at
+	// roughly 100µs.
+	//
+	// Must be a multiple of the pageInUse bitmap element size and
+	// must also evenly divide pagesPerArena.
+	pagesPerReclaimerChunk = 512
+
+	// physPageAlignedStacks indicates whether stack allocations must be
+	// physical page aligned. This is a requirement for MAP_STACK on
+	// OpenBSD.
+	physPageAlignedStacks = GOOS == "openbsd"
+)
+
+// Main malloc heap.
+// The heap itself is the "free" and "scav" treaps,
+// but all the other global data is here too.
+//
+// mheap must not be heap-allocated because it contains mSpanLists,
+// which must not be heap-allocated.
+//
+//go:notinheap
+type mheap struct {
+	// lock must only be acquired on the system stack, otherwise a g
+	// could self-deadlock if its stack grows with the lock held.
+	lock mutex
+
+	_ uint32 // 8-byte align pages so its alignment is consistent with tests.
+
+	pages pageAlloc // page allocation data structure
+
+	sweepgen uint32 // sweep generation, see comment in mspan; written during STW
+
+	// allspans is a slice of all mspans ever created. Each mspan
+	// appears exactly once.
+	//
+	// The memory for allspans is manually managed and can be
+	// reallocated and move as the heap grows.
+	//
+	// In general, allspans is protected by mheap_.lock, which
+	// prevents concurrent access as well as freeing the backing
+	// store. Accesses during STW might not hold the lock, but
+	// must ensure that allocation cannot happen around the
+	// access (since that may free the backing store).
+	allspans []*mspan // all spans out there
+
+	// _ uint32 // align uint64 fields on 32-bit for atomics
+
+	// Proportional sweep
+	//
+	// These parameters represent a linear function from gcController.heapLive
+	// to page sweep count. The proportional sweep system works to
+	// stay in the black by keeping the current page sweep count
+	// above this line at the current gcController.heapLive.
+	//
+	// The line has slope sweepPagesPerByte and passes through a
+	// basis point at (sweepHeapLiveBasis, pagesSweptBasis). At
+	// any given time, the system is at (gcController.heapLive,
+	// pagesSwept) in this space.
+	//
+	// It is important that the line pass through a point we
+	// control rather than simply starting at a 0,0 origin
+	// because that lets us adjust sweep pacing at any time while
+	// accounting for current progress. If we could only adjust
+	// the slope, it would create a discontinuity in debt if any
+	// progress has already been made.
+	pagesInUse         atomic.Uint64 // pages of spans in stats mSpanInUse
+	pagesSwept         atomic.Uint64 // pages swept this cycle
+	pagesSweptBasis    atomic.Uint64 // pagesSwept to use as the origin of the sweep ratio
+	sweepHeapLiveBasis uint64        // value of gcController.heapLive to use as the origin of sweep ratio; written with lock, read without
+	sweepPagesPerByte  float64       // proportional sweep ratio; written with lock, read without
+	// TODO(austin): pagesInUse should be a uintptr, but the 386
+	// compiler can't 8-byte align fields.
+
+	// Page reclaimer state
+
+	// reclaimIndex is the page index in allArenas of next page to
+	// reclaim. Specifically, it refers to page (i %
+	// pagesPerArena) of arena allArenas[i / pagesPerArena].
+	//
+	// If this is >= 1<<63, the page reclaimer is done scanning
+	// the page marks.
+	reclaimIndex atomic.Uint64
+
+	// reclaimCredit is spare credit for extra pages swept. Since
+	// the page reclaimer works in large chunks, it may reclaim
+	// more than requested. Any spare pages released go to this
+	// credit pool.
+	reclaimCredit atomic.Uintptr
+
+	// arenas is the heap arena map. It points to the metadata for
+	// the heap for every arena frame of the entire usable virtual
+	// address space.
+	//
+	// Use arenaIndex to compute indexes into this array.
+	//
+	// For regions of the address space that are not backed by the
+	// Go heap, the arena map contains nil.
+	//
+	// Modifications are protected by mheap_.lock. Reads can be
+	// performed without locking; however, a given entry can
+	// transition from nil to non-nil at any time when the lock
+	// isn't held. (Entries never transitions back to nil.)
+	//
+	// In general, this is a two-level mapping consisting of an L1
+	// map and possibly many L2 maps. This saves space when there
+	// are a huge number of arena frames. However, on many
+	// platforms (even 64-bit), arenaL1Bits is 0, making this
+	// effectively a single-level map. In this case, arenas[0]
+	// will never be nil.
+	arenas [1 << arenaL1Bits]*[1 << arenaL2Bits]*heapArena
+
+	// heapArenaAlloc is pre-reserved space for allocating heapArena
+	// objects. This is only used on 32-bit, where we pre-reserve
+	// this space to avoid interleaving it with the heap itself.
+	heapArenaAlloc linearAlloc
+
+	// arenaHints is a list of addresses at which to attempt to
+	// add more heap arenas. This is initially populated with a
+	// set of general hint addresses, and grown with the bounds of
+	// actual heap arena ranges.
+	arenaHints *arenaHint
+
+	// arena is a pre-reserved space for allocating heap arenas
+	// (the actual arenas). This is only used on 32-bit.
+	arena linearAlloc
+
+	// allArenas is the arenaIndex of every mapped arena. This can
+	// be used to iterate through the address space.
+	//
+	// Access is protected by mheap_.lock. However, since this is
+	// append-only and old backing arrays are never freed, it is
+	// safe to acquire mheap_.lock, copy the slice header, and
+	// then release mheap_.lock.
+	allArenas []arenaIdx
+
+	// sweepArenas is a snapshot of allArenas taken at the
+	// beginning of the sweep cycle. This can be read safely by
+	// simply blocking GC (by disabling preemption).
+	sweepArenas []arenaIdx
+
+	// markArenas is a snapshot of allArenas taken at the beginning
+	// of the mark cycle. Because allArenas is append-only, neither
+	// this slice nor its contents will change during the mark, so
+	// it can be read safely.
+	markArenas []arenaIdx
+
+	// curArena is the arena that the heap is currently growing
+	// into. This should always be physPageSize-aligned.
+	curArena struct {
+		base, end uintptr
+	}
+
+	_ uint32 // ensure 64-bit alignment of central
+
+	// central free lists for small size classes.
+	// the padding makes sure that the mcentrals are
+	// spaced CacheLinePadSize bytes apart, so that each mcentral.lock
+	// gets its own cache line.
+	// central is indexed by spanClass.
+	central [numSpanClasses]struct {
+		mcentral mcentral
+		pad      [cpu.CacheLinePadSize - unsafe.Sizeof(mcentral{})%cpu.CacheLinePadSize]byte
+	}
+
+	spanalloc             fixalloc // allocator for span*
+	cachealloc            fixalloc // allocator for mcache*
+	specialfinalizeralloc fixalloc // allocator for specialfinalizer*
+	specialprofilealloc   fixalloc // allocator for specialprofile*
+	specialReachableAlloc fixalloc // allocator for specialReachable
+	speciallock           mutex    // lock for special record allocators.
+	arenaHintAlloc        fixalloc // allocator for arenaHints
+
+	unused *specialfinalizer // never set, just here to force the specialfinalizer type into DWARF
+}
+
+var mheap_ mheap
+
+// A heapArena stores metadata for a heap arena. heapArenas are stored
+// outside of the Go heap and accessed via the mheap_.arenas index.
+//
+//go:notinheap
+type heapArena struct {
+	// bitmap stores the pointer/scalar bitmap for the words in
+	// this arena. See mbitmap.go for a description. Use the
+	// heapBits type to access this.
+	bitmap [heapArenaBitmapBytes]byte
+
+	// spans maps from virtual address page ID within this arena to *mspan.
+	// For allocated spans, their pages map to the span itself.
+	// For free spans, only the lowest and highest pages map to the span itself.
+	// Internal pages map to an arbitrary span.
+	// For pages that have never been allocated, spans entries are nil.
+	//
+	// Modifications are protected by mheap.lock. Reads can be
+	// performed without locking, but ONLY from indexes that are
+	// known to contain in-use or stack spans. This means there
+	// must not be a safe-point between establishing that an
+	// address is live and looking it up in the spans array.
+	spans [pagesPerArena]*mspan
+
+	// pageInUse is a bitmap that indicates which spans are in
+	// state mSpanInUse. This bitmap is indexed by page number,
+	// but only the bit corresponding to the first page in each
+	// span is used.
+	//
+	// Reads and writes are atomic.
+	pageInUse [pagesPerArena / 8]uint8
+
+	// pageMarks is a bitmap that indicates which spans have any
+	// marked objects on them. Like pageInUse, only the bit
+	// corresponding to the first page in each span is used.
+	//
+	// Writes are done atomically during marking. Reads are
+	// non-atomic and lock-free since they only occur during
+	// sweeping (and hence never race with writes).
+	//
+	// This is used to quickly find whole spans that can be freed.
+	//
+	// TODO(austin): It would be nice if this was uint64 for
+	// faster scanning, but we don't have 64-bit atomic bit
+	// operations.
+	pageMarks [pagesPerArena / 8]uint8
+
+	// pageSpecials is a bitmap that indicates which spans have
+	// specials (finalizers or other). Like pageInUse, only the bit
+	// corresponding to the first page in each span is used.
+	//
+	// Writes are done atomically whenever a special is added to
+	// a span and whenever the last special is removed from a span.
+	// Reads are done atomically to find spans containing specials
+	// during marking.
+	pageSpecials [pagesPerArena / 8]uint8
+
+	// checkmarks stores the debug.gccheckmark state. It is only
+	// used if debug.gccheckmark > 0.
+	checkmarks *checkmarksMap
+
+	// zeroedBase marks the first byte of the first page in this
+	// arena which hasn't been used yet and is therefore already
+	// zero. zeroedBase is relative to the arena base.
+	// Increases monotonically until it hits heapArenaBytes.
+	//
+	// This field is sufficient to determine if an allocation
+	// needs to be zeroed because the page allocator follows an
+	// address-ordered first-fit policy.
+	//
+	// Read atomically and written with an atomic CAS.
+	zeroedBase uintptr
+}
+
+// arenaHint is a hint for where to grow the heap arenas. See
+// mheap_.arenaHints.
+//
+//go:notinheap
+type arenaHint struct {
+	addr uintptr
+	down bool
+	next *arenaHint
+}
+
+// An mspan is a run of pages.
+//
+// When a mspan is in the heap free treap, state == mSpanFree
+// and heapmap(s->start) == span, heapmap(s->start+s->npages-1) == span.
+// If the mspan is in the heap scav treap, then in addition to the
+// above scavenged == true. scavenged == false in all other cases.
+//
+// When a mspan is allocated, state == mSpanInUse or mSpanManual
+// and heapmap(i) == span for all s->start <= i < s->start+s->npages.
+
+// Every mspan is in one doubly-linked list, either in the mheap's
+// busy list or one of the mcentral's span lists.
+
+// An mspan representing actual memory has state mSpanInUse,
+// mSpanManual, or mSpanFree. Transitions between these states are
+// constrained as follows:
+//
+//   - A span may transition from free to in-use or manual during any GC
+//     phase.
+//
+//   - During sweeping (gcphase == _GCoff), a span may transition from
+//     in-use to free (as a result of sweeping) or manual to free (as a
+//     result of stacks being freed).
+//
+//   - During GC (gcphase != _GCoff), a span *must not* transition from
+//     manual or in-use to free. Because concurrent GC may read a pointer
+//     and then look up its span, the span state must be monotonic.
+//
+// Setting mspan.state to mSpanInUse or mSpanManual must be done
+// atomically and only after all other span fields are valid.
+// Likewise, if inspecting a span is contingent on it being
+// mSpanInUse, the state should be loaded atomically and checked
+// before depending on other fields. This allows the garbage collector
+// to safely deal with potentially invalid pointers, since resolving
+// such pointers may race with a span being allocated.
+type mSpanState uint8
+
+const (
+	mSpanDead   mSpanState = iota
+	mSpanInUse             // allocated for garbage collected heap
+	mSpanManual            // allocated for manual management (e.g., stack allocator)
+)
+
+// mSpanStateNames are the names of the span states, indexed by
+// mSpanState.
+var mSpanStateNames = []string{
+	"mSpanDead",
+	"mSpanInUse",
+	"mSpanManual",
+	"mSpanFree",
+}
+
+// mSpanStateBox holds an mSpanState and provides atomic operations on
+// it. This is a separate type to disallow accidental comparison or
+// assignment with mSpanState.
+type mSpanStateBox struct {
+	s mSpanState
+}
+
+func (b *mSpanStateBox) set(s mSpanState) {
+	atomic.Store8((*uint8)(&b.s), uint8(s))
+}
+
+func (b *mSpanStateBox) get() mSpanState {
+	return mSpanState(atomic.Load8((*uint8)(&b.s)))
+}
+
+// mSpanList heads a linked list of spans.
+//
+//go:notinheap
+type mSpanList struct {
+	first *mspan // first span in list, or nil if none
+	last  *mspan // last span in list, or nil if none
+}
+
+//go:notinheap
+type mspan struct {
+	next *mspan     // next span in list, or nil if none
+	prev *mspan     // previous span in list, or nil if none
+	list *mSpanList // For debugging. TODO: Remove.
+
+	startAddr uintptr // address of first byte of span aka s.base()
+	npages    uintptr // number of pages in span
+
+	manualFreeList gclinkptr // list of free objects in mSpanManual spans
+
+	// freeindex is the slot index between 0 and nelems at which to begin scanning
+	// for the next free object in this span.
+	// Each allocation scans allocBits starting at freeindex until it encounters a 0
+	// indicating a free object. freeindex is then adjusted so that subsequent scans begin
+	// just past the newly discovered free object.
+	//
+	// If freeindex == nelem, this span has no free objects.
+	//
+	// allocBits is a bitmap of objects in this span.
+	// If n >= freeindex and allocBits[n/8] & (1<<(n%8)) is 0
+	// then object n is free;
+	// otherwise, object n is allocated. Bits starting at nelem are
+	// undefined and should never be referenced.
+	//
+	// Object n starts at address n*elemsize + (start << pageShift).
+	freeindex uintptr
+	// TODO: Look up nelems from sizeclass and remove this field if it
+	// helps performance.
+	nelems uintptr // number of object in the span.
+
+	// Cache of the allocBits at freeindex. allocCache is shifted
+	// such that the lowest bit corresponds to the bit freeindex.
+	// allocCache holds the complement of allocBits, thus allowing
+	// ctz (count trailing zero) to use it directly.
+	// allocCache may contain bits beyond s.nelems; the caller must ignore
+	// these.
+	allocCache uint64
+
+	// allocBits and gcmarkBits hold pointers to a span's mark and
+	// allocation bits. The pointers are 8 byte aligned.
+	// There are three arenas where this data is held.
+	// free: Dirty arenas that are no longer accessed
+	//       and can be reused.
+	// next: Holds information to be used in the next GC cycle.
+	// current: Information being used during this GC cycle.
+	// previous: Information being used during the last GC cycle.
+	// A new GC cycle starts with the call to finishsweep_m.
+	// finishsweep_m moves the previous arena to the free arena,
+	// the current arena to the previous arena, and
+	// the next arena to the current arena.
+	// The next arena is populated as the spans request
+	// memory to hold gcmarkBits for the next GC cycle as well
+	// as allocBits for newly allocated spans.
+	//
+	// The pointer arithmetic is done "by hand" instead of using
+	// arrays to avoid bounds checks along critical performance
+	// paths.
+	// The sweep will free the old allocBits and set allocBits to the
+	// gcmarkBits. The gcmarkBits are replaced with a fresh zeroed
+	// out memory.
+	allocBits  *gcBits
+	gcmarkBits *gcBits
+
+	// sweep generation:
+	// if sweepgen == h->sweepgen - 2, the span needs sweeping
+	// if sweepgen == h->sweepgen - 1, the span is currently being swept
+	// if sweepgen == h->sweepgen, the span is swept and ready to use
+	// if sweepgen == h->sweepgen + 1, the span was cached before sweep began and is still cached, and needs sweeping
+	// if sweepgen == h->sweepgen + 3, the span was swept and then cached and is still cached
+	// h->sweepgen is incremented by 2 after every GC
+
+	sweepgen              uint32
+	divMul                uint32        // for divide by elemsize
+	allocCount            uint16        // number of allocated objects
+	spanclass             spanClass     // size class and noscan (uint8)
+	state                 mSpanStateBox // mSpanInUse etc; accessed atomically (get/set methods)
+	needzero              uint8         // needs to be zeroed before allocation
+	allocCountBeforeCache uint16        // a copy of allocCount that is stored just before this span is cached
+	elemsize              uintptr       // computed from sizeclass or from npages
+	limit                 uintptr       // end of data in span
+	speciallock           mutex         // guards specials list
+	specials              *special      // linked list of special records sorted by offset.
+}
+
+func (s *mspan) base() uintptr {
+	return s.startAddr
+}
+
+func (s *mspan) layout() (size, n, total uintptr) {
+	total = s.npages << _PageShift
+	size = s.elemsize
+	if size > 0 {
+		n = total / size
+	}
+	return
+}
+
+// recordspan adds a newly allocated span to h.allspans.
+//
+// This only happens the first time a span is allocated from
+// mheap.spanalloc (it is not called when a span is reused).
+//
+// Write barriers are disallowed here because it can be called from
+// gcWork when allocating new workbufs. However, because it's an
+// indirect call from the fixalloc initializer, the compiler can't see
+// this.
+//
+// The heap lock must be held.
+//
+//go:nowritebarrierrec
+func recordspan(vh unsafe.Pointer, p unsafe.Pointer) {
+	h := (*mheap)(vh)
+	s := (*mspan)(p)
+
+	assertLockHeld(&h.lock)
+
+	if len(h.allspans) >= cap(h.allspans) {
+		n := 64 * 1024 / goarch.PtrSize
+		if n < cap(h.allspans)*3/2 {
+			n = cap(h.allspans) * 3 / 2
+		}
+		var new []*mspan
+		sp := (*slice)(unsafe.Pointer(&new))
+		sp.array = sysAlloc(uintptr(n)*goarch.PtrSize, &memstats.other_sys)
+		if sp.array == nil {
+			throw("runtime: cannot allocate memory")
+		}
+		sp.len = len(h.allspans)
+		sp.cap = n
+		if len(h.allspans) > 0 {
+			copy(new, h.allspans)
+		}
+		oldAllspans := h.allspans
+		*(*notInHeapSlice)(unsafe.Pointer(&h.allspans)) = *(*notInHeapSlice)(unsafe.Pointer(&new))
+		if len(oldAllspans) != 0 {
+			sysFree(unsafe.Pointer(&oldAllspans[0]), uintptr(cap(oldAllspans))*unsafe.Sizeof(oldAllspans[0]), &memstats.other_sys)
+		}
+	}
+	h.allspans = h.allspans[:len(h.allspans)+1]
+	h.allspans[len(h.allspans)-1] = s
+}
+
+// A spanClass represents the size class and noscan-ness of a span.
+//
+// Each size class has a noscan spanClass and a scan spanClass. The
+// noscan spanClass contains only noscan objects, which do not contain
+// pointers and thus do not need to be scanned by the garbage
+// collector.
+type spanClass uint8
+
+const (
+	numSpanClasses = _NumSizeClasses << 1
+	tinySpanClass  = spanClass(tinySizeClass<<1 | 1)
+)
+
+func makeSpanClass(sizeclass uint8, noscan bool) spanClass {
+	return spanClass(sizeclass<<1) | spanClass(bool2int(noscan))
+}
+
+func (sc spanClass) sizeclass() int8 {
+	return int8(sc >> 1)
+}
+
+func (sc spanClass) noscan() bool {
+	return sc&1 != 0
+}
+
+// arenaIndex returns the index into mheap_.arenas of the arena
+// containing metadata for p. This index combines of an index into the
+// L1 map and an index into the L2 map and should be used as
+// mheap_.arenas[ai.l1()][ai.l2()].
+//
+// If p is outside the range of valid heap addresses, either l1() or
+// l2() will be out of bounds.
+//
+// It is nosplit because it's called by spanOf and several other
+// nosplit functions.
+//
+//go:nosplit
+func arenaIndex(p uintptr) arenaIdx {
+	return arenaIdx((p - arenaBaseOffset) / heapArenaBytes)
+}
+
+// arenaBase returns the low address of the region covered by heap
+// arena i.
+func arenaBase(i arenaIdx) uintptr {
+	return uintptr(i)*heapArenaBytes + arenaBaseOffset
+}
+
+type arenaIdx uint
+
+func (i arenaIdx) l1() uint {
+	if arenaL1Bits == 0 {
+		// Let the compiler optimize this away if there's no
+		// L1 map.
+		return 0
+	} else {
+		return uint(i) >> arenaL1Shift
+	}
+}
+
+func (i arenaIdx) l2() uint {
+	if arenaL1Bits == 0 {
+		return uint(i)
+	} else {
+		return uint(i) & (1<<arenaL2Bits - 1)
+	}
+}
+
+// inheap reports whether b is a pointer into a (potentially dead) heap object.
+// It returns false for pointers into mSpanManual spans.
+// Non-preemptible because it is used by write barriers.
+//
+//go:nowritebarrier
+//go:nosplit
+func inheap(b uintptr) bool {
+	return spanOfHeap(b) != nil
+}
+
+// inHeapOrStack is a variant of inheap that returns true for pointers
+// into any allocated heap span.
+//
+//go:nowritebarrier
+//go:nosplit
+func inHeapOrStack(b uintptr) bool {
+	s := spanOf(b)
+	if s == nil || b < s.base() {
+		return false
+	}
+	switch s.state.get() {
+	case mSpanInUse, mSpanManual:
+		return b < s.limit
+	default:
+		return false
+	}
+}
+
+// spanOf returns the span of p. If p does not point into the heap
+// arena or no span has ever contained p, spanOf returns nil.
+//
+// If p does not point to allocated memory, this may return a non-nil
+// span that does *not* contain p. If this is a possibility, the
+// caller should either call spanOfHeap or check the span bounds
+// explicitly.
+//
+// Must be nosplit because it has callers that are nosplit.
+//
+//go:nosplit
+func spanOf(p uintptr) *mspan {
+	// This function looks big, but we use a lot of constant
+	// folding around arenaL1Bits to get it under the inlining
+	// budget. Also, many of the checks here are safety checks
+	// that Go needs to do anyway, so the generated code is quite
+	// short.
+	ri := arenaIndex(p)
+	if arenaL1Bits == 0 {
+		// If there's no L1, then ri.l1() can't be out of bounds but ri.l2() can.
+		if ri.l2() >= uint(len(mheap_.arenas[0])) {
+			return nil
+		}
+	} else {
+		// If there's an L1, then ri.l1() can be out of bounds but ri.l2() can't.
+		if ri.l1() >= uint(len(mheap_.arenas)) {
+			return nil
+		}
+	}
+	l2 := mheap_.arenas[ri.l1()]
+	if arenaL1Bits != 0 && l2 == nil { // Should never happen if there's no L1.
+		return nil
+	}
+	ha := l2[ri.l2()]
+	if ha == nil {
+		return nil
+	}
+	return ha.spans[(p/pageSize)%pagesPerArena]
+}
+
+// spanOfUnchecked is equivalent to spanOf, but the caller must ensure
+// that p points into an allocated heap arena.
+//
+// Must be nosplit because it has callers that are nosplit.
+//
+//go:nosplit
+func spanOfUnchecked(p uintptr) *mspan {
+	ai := arenaIndex(p)
+	return mheap_.arenas[ai.l1()][ai.l2()].spans[(p/pageSize)%pagesPerArena]
+}
+
+// spanOfHeap is like spanOf, but returns nil if p does not point to a
+// heap object.
+//
+// Must be nosplit because it has callers that are nosplit.
+//
+//go:nosplit
+func spanOfHeap(p uintptr) *mspan {
+	s := spanOf(p)
+	// s is nil if it's never been allocated. Otherwise, we check
+	// its state first because we don't trust this pointer, so we
+	// have to synchronize with span initialization. Then, it's
+	// still possible we picked up a stale span pointer, so we
+	// have to check the span's bounds.
+	if s == nil || s.state.get() != mSpanInUse || p < s.base() || p >= s.limit {
+		return nil
+	}
+	return s
+}
+
+// pageIndexOf returns the arena, page index, and page mask for pointer p.
+// The caller must ensure p is in the heap.
+func pageIndexOf(p uintptr) (arena *heapArena, pageIdx uintptr, pageMask uint8) {
+	ai := arenaIndex(p)
+	arena = mheap_.arenas[ai.l1()][ai.l2()]
+	pageIdx = ((p / pageSize) / 8) % uintptr(len(arena.pageInUse))
+	pageMask = byte(1 << ((p / pageSize) % 8))
+	return
+}
+
+// Initialize the heap.
+func (h *mheap) init() {
+	lockInit(&h.lock, lockRankMheap)
+	lockInit(&h.speciallock, lockRankMheapSpecial)
+
+	h.spanalloc.init(unsafe.Sizeof(mspan{}), recordspan, unsafe.Pointer(h), &memstats.mspan_sys)
+	h.cachealloc.init(unsafe.Sizeof(mcache{}), nil, nil, &memstats.mcache_sys)
+	h.specialfinalizeralloc.init(unsafe.Sizeof(specialfinalizer{}), nil, nil, &memstats.other_sys)
+	h.specialprofilealloc.init(unsafe.Sizeof(specialprofile{}), nil, nil, &memstats.other_sys)
+	h.specialReachableAlloc.init(unsafe.Sizeof(specialReachable{}), nil, nil, &memstats.other_sys)
+	h.arenaHintAlloc.init(unsafe.Sizeof(arenaHint{}), nil, nil, &memstats.other_sys)
+
+	// Don't zero mspan allocations. Background sweeping can
+	// inspect a span concurrently with allocating it, so it's
+	// important that the span's sweepgen survive across freeing
+	// and re-allocating a span to prevent background sweeping
+	// from improperly cas'ing it from 0.
+	//
+	// This is safe because mspan contains no heap pointers.
+	h.spanalloc.zero = false
+
+	// h->mapcache needs no init
+
+	for i := range h.central {
+		h.central[i].mcentral.init(spanClass(i))
+	}
+
+	h.pages.init(&h.lock, &memstats.gcMiscSys)
+}
+
+// reclaim sweeps and reclaims at least npage pages into the heap.
+// It is called before allocating npage pages to keep growth in check.
+//
+// reclaim implements the page-reclaimer half of the sweeper.
+//
+// h.lock must NOT be held.
+func (h *mheap) reclaim(npage uintptr) {
+	// TODO(austin): Half of the time spent freeing spans is in
+	// locking/unlocking the heap (even with low contention). We
+	// could make the slow path here several times faster by
+	// batching heap frees.
+
+	// Bail early if there's no more reclaim work.
+	if h.reclaimIndex.Load() >= 1<<63 {
+		return
+	}
+
+	// Disable preemption so the GC can't start while we're
+	// sweeping, so we can read h.sweepArenas, and so
+	// traceGCSweepStart/Done pair on the P.
+	mp := acquirem()
+
+	if trace.enabled {
+		traceGCSweepStart()
+	}
+
+	arenas := h.sweepArenas
+	locked := false
+	for npage > 0 {
+		// Pull from accumulated credit first.
+		if credit := h.reclaimCredit.Load(); credit > 0 {
+			take := credit
+			if take > npage {
+				// Take only what we need.
+				take = npage
+			}
+			if h.reclaimCredit.CompareAndSwap(credit, credit-take) {
+				npage -= take
+			}
+			continue
+		}
+
+		// Claim a chunk of work.
+		idx := uintptr(h.reclaimIndex.Add(pagesPerReclaimerChunk) - pagesPerReclaimerChunk)
+		if idx/pagesPerArena >= uintptr(len(arenas)) {
+			// Page reclaiming is done.
+			h.reclaimIndex.Store(1 << 63)
+			break
+		}
+
+		if !locked {
+			// Lock the heap for reclaimChunk.
+			lock(&h.lock)
+			locked = true
+		}
+
+		// Scan this chunk.
+		nfound := h.reclaimChunk(arenas, idx, pagesPerReclaimerChunk)
+		if nfound <= npage {
+			npage -= nfound
+		} else {
+			// Put spare pages toward global credit.
+			h.reclaimCredit.Add(nfound - npage)
+			npage = 0
+		}
+	}
+	if locked {
+		unlock(&h.lock)
+	}
+
+	if trace.enabled {
+		traceGCSweepDone()
+	}
+	releasem(mp)
+}
+
+// reclaimChunk sweeps unmarked spans that start at page indexes [pageIdx, pageIdx+n).
+// It returns the number of pages returned to the heap.
+//
+// h.lock must be held and the caller must be non-preemptible. Note: h.lock may be
+// temporarily unlocked and re-locked in order to do sweeping or if tracing is
+// enabled.
+func (h *mheap) reclaimChunk(arenas []arenaIdx, pageIdx, n uintptr) uintptr {
+	// The heap lock must be held because this accesses the
+	// heapArena.spans arrays using potentially non-live pointers.
+	// In particular, if a span were freed and merged concurrently
+	// with this probing heapArena.spans, it would be possible to
+	// observe arbitrary, stale span pointers.
+	assertLockHeld(&h.lock)
+
+	n0 := n
+	var nFreed uintptr
+	sl := sweep.active.begin()
+	if !sl.valid {
+		return 0
+	}
+	for n > 0 {
+		ai := arenas[pageIdx/pagesPerArena]
+		ha := h.arenas[ai.l1()][ai.l2()]
+
+		// Get a chunk of the bitmap to work on.
+		arenaPage := uint(pageIdx % pagesPerArena)
+		inUse := ha.pageInUse[arenaPage/8:]
+		marked := ha.pageMarks[arenaPage/8:]
+		if uintptr(len(inUse)) > n/8 {
+			inUse = inUse[:n/8]
+			marked = marked[:n/8]
+		}
+
+		// Scan this bitmap chunk for spans that are in-use
+		// but have no marked objects on them.
+		for i := range inUse {
+			inUseUnmarked := atomic.Load8(&inUse[i]) &^ marked[i]
+			if inUseUnmarked == 0 {
+				continue
+			}
+
+			for j := uint(0); j < 8; j++ {
+				if inUseUnmarked&(1<<j) != 0 {
+					s := ha.spans[arenaPage+uint(i)*8+j]
+					if s, ok := sl.tryAcquire(s); ok {
+						npages := s.npages
+						unlock(&h.lock)
+						if s.sweep(false) {
+							nFreed += npages
+						}
+						lock(&h.lock)
+						// Reload inUse. It's possible nearby
+						// spans were freed when we dropped the
+						// lock and we don't want to get stale
+						// pointers from the spans array.
+						inUseUnmarked = atomic.Load8(&inUse[i]) &^ marked[i]
+					}
+				}
+			}
+		}
+
+		// Advance.
+		pageIdx += uintptr(len(inUse) * 8)
+		n -= uintptr(len(inUse) * 8)
+	}
+	sweep.active.end(sl)
+	if trace.enabled {
+		unlock(&h.lock)
+		// Account for pages scanned but not reclaimed.
+		traceGCSweepSpan((n0 - nFreed) * pageSize)
+		lock(&h.lock)
+	}
+
+	assertLockHeld(&h.lock) // Must be locked on return.
+	return nFreed
+}
+
+// spanAllocType represents the type of allocation to make, or
+// the type of allocation to be freed.
+type spanAllocType uint8
+
+const (
+	spanAllocHeap          spanAllocType = iota // heap span
+	spanAllocStack                              // stack span
+	spanAllocPtrScalarBits                      // unrolled GC prog bitmap span
+	spanAllocWorkBuf                            // work buf span
+)
+
+// manual returns true if the span allocation is manually managed.
+func (s spanAllocType) manual() bool {
+	return s != spanAllocHeap
+}
+
+// alloc allocates a new span of npage pages from the GC'd heap.
+//
+// spanclass indicates the span's size class and scannability.
+//
+// Returns a span that has been fully initialized. span.needzero indicates
+// whether the span has been zeroed. Note that it may not be.
+func (h *mheap) alloc(npages uintptr, spanclass spanClass) *mspan {
+	// Don't do any operations that lock the heap on the G stack.
+	// It might trigger stack growth, and the stack growth code needs
+	// to be able to allocate heap.
+	var s *mspan
+	systemstack(func() {
+		// To prevent excessive heap growth, before allocating n pages
+		// we need to sweep and reclaim at least n pages.
+		if !isSweepDone() {
+			h.reclaim(npages)
+		}
+		s = h.allocSpan(npages, spanAllocHeap, spanclass)
+	})
+	return s
+}
+
+// allocManual allocates a manually-managed span of npage pages.
+// allocManual returns nil if allocation fails.
+//
+// allocManual adds the bytes used to *stat, which should be a
+// memstats in-use field. Unlike allocations in the GC'd heap, the
+// allocation does *not* count toward heapInUse.
+//
+// The memory backing the returned span may not be zeroed if
+// span.needzero is set.
+//
+// allocManual must be called on the system stack because it may
+// acquire the heap lock via allocSpan. See mheap for details.
+//
+// If new code is written to call allocManual, do NOT use an
+// existing spanAllocType value and instead declare a new one.
+//
+//go:systemstack
+func (h *mheap) allocManual(npages uintptr, typ spanAllocType) *mspan {
+	if !typ.manual() {
+		throw("manual span allocation called with non-manually-managed type")
+	}
+	return h.allocSpan(npages, typ, 0)
+}
+
+// setSpans modifies the span map so [spanOf(base), spanOf(base+npage*pageSize))
+// is s.
+func (h *mheap) setSpans(base, npage uintptr, s *mspan) {
+	p := base / pageSize
+	ai := arenaIndex(base)
+	ha := h.arenas[ai.l1()][ai.l2()]
+	for n := uintptr(0); n < npage; n++ {
+		i := (p + n) % pagesPerArena
+		if i == 0 {
+			ai = arenaIndex(base + n*pageSize)
+			ha = h.arenas[ai.l1()][ai.l2()]
+		}
+		ha.spans[i] = s
+	}
+}
+
+// allocNeedsZero checks if the region of address space [base, base+npage*pageSize),
+// assumed to be allocated, needs to be zeroed, updating heap arena metadata for
+// future allocations.
+//
+// This must be called each time pages are allocated from the heap, even if the page
+// allocator can otherwise prove the memory it's allocating is already zero because
+// they're fresh from the operating system. It updates heapArena metadata that is
+// critical for future page allocations.
+//
+// There are no locking constraints on this method.
+func (h *mheap) allocNeedsZero(base, npage uintptr) (needZero bool) {
+	for npage > 0 {
+		ai := arenaIndex(base)
+		ha := h.arenas[ai.l1()][ai.l2()]
+
+		zeroedBase := atomic.Loaduintptr(&ha.zeroedBase)
+		arenaBase := base % heapArenaBytes
+		if arenaBase < zeroedBase {
+			// We extended into the non-zeroed part of the
+			// arena, so this region needs to be zeroed before use.
+			//
+			// zeroedBase is monotonically increasing, so if we see this now then
+			// we can be sure we need to zero this memory region.
+			//
+			// We still need to update zeroedBase for this arena, and
+			// potentially more arenas.
+			needZero = true
+		}
+		// We may observe arenaBase > zeroedBase if we're racing with one or more
+		// allocations which are acquiring memory directly before us in the address
+		// space. But, because we know no one else is acquiring *this* memory, it's
+		// still safe to not zero.
+
+		// Compute how far into the arena we extend into, capped
+		// at heapArenaBytes.
+		arenaLimit := arenaBase + npage*pageSize
+		if arenaLimit > heapArenaBytes {
+			arenaLimit = heapArenaBytes
+		}
+		// Increase ha.zeroedBase so it's >= arenaLimit.
+		// We may be racing with other updates.
+		for arenaLimit > zeroedBase {
+			if atomic.Casuintptr(&ha.zeroedBase, zeroedBase, arenaLimit) {
+				break
+			}
+			zeroedBase = atomic.Loaduintptr(&ha.zeroedBase)
+			// Double check basic conditions of zeroedBase.
+			if zeroedBase <= arenaLimit && zeroedBase > arenaBase {
+				// The zeroedBase moved into the space we were trying to
+				// claim. That's very bad, and indicates someone allocated
+				// the same region we did.
+				throw("potentially overlapping in-use allocations detected")
+			}
+		}
+
+		// Move base forward and subtract from npage to move into
+		// the next arena, or finish.
+		base += arenaLimit - arenaBase
+		npage -= (arenaLimit - arenaBase) / pageSize
+	}
+	return
+}
+
+// tryAllocMSpan attempts to allocate an mspan object from
+// the P-local cache, but may fail.
+//
+// h.lock need not be held.
+//
+// This caller must ensure that its P won't change underneath
+// it during this function. Currently to ensure that we enforce
+// that the function is run on the system stack, because that's
+// the only place it is used now. In the future, this requirement
+// may be relaxed if its use is necessary elsewhere.
+//
+//go:systemstack
+func (h *mheap) tryAllocMSpan() *mspan {
+	pp := getg().m.p.ptr()
+	// If we don't have a p or the cache is empty, we can't do
+	// anything here.
+	if pp == nil || pp.mspancache.len == 0 {
+		return nil
+	}
+	// Pull off the last entry in the cache.
+	s := pp.mspancache.buf[pp.mspancache.len-1]
+	pp.mspancache.len--
+	return s
+}
+
+// allocMSpanLocked allocates an mspan object.
+//
+// h.lock must be held.
+//
+// allocMSpanLocked must be called on the system stack because
+// its caller holds the heap lock. See mheap for details.
+// Running on the system stack also ensures that we won't
+// switch Ps during this function. See tryAllocMSpan for details.
+//
+//go:systemstack
+func (h *mheap) allocMSpanLocked() *mspan {
+	assertLockHeld(&h.lock)
+
+	pp := getg().m.p.ptr()
+	if pp == nil {
+		// We don't have a p so just do the normal thing.
+		return (*mspan)(h.spanalloc.alloc())
+	}
+	// Refill the cache if necessary.
+	if pp.mspancache.len == 0 {
+		const refillCount = len(pp.mspancache.buf) / 2
+		for i := 0; i < refillCount; i++ {
+			pp.mspancache.buf[i] = (*mspan)(h.spanalloc.alloc())
+		}
+		pp.mspancache.len = refillCount
+	}
+	// Pull off the last entry in the cache.
+	s := pp.mspancache.buf[pp.mspancache.len-1]
+	pp.mspancache.len--
+	return s
+}
+
+// freeMSpanLocked free an mspan object.
+//
+// h.lock must be held.
+//
+// freeMSpanLocked must be called on the system stack because
+// its caller holds the heap lock. See mheap for details.
+// Running on the system stack also ensures that we won't
+// switch Ps during this function. See tryAllocMSpan for details.
+//
+//go:systemstack
+func (h *mheap) freeMSpanLocked(s *mspan) {
+	assertLockHeld(&h.lock)
+
+	pp := getg().m.p.ptr()
+	// First try to free the mspan directly to the cache.
+	if pp != nil && pp.mspancache.len < len(pp.mspancache.buf) {
+		pp.mspancache.buf[pp.mspancache.len] = s
+		pp.mspancache.len++
+		return
+	}
+	// Failing that (or if we don't have a p), just free it to
+	// the heap.
+	h.spanalloc.free(unsafe.Pointer(s))
+}
+
+// allocSpan allocates an mspan which owns npages worth of memory.
+//
+// If typ.manual() == false, allocSpan allocates a heap span of class spanclass
+// and updates heap accounting. If manual == true, allocSpan allocates a
+// manually-managed span (spanclass is ignored), and the caller is
+// responsible for any accounting related to its use of the span. Either
+// way, allocSpan will atomically add the bytes in the newly allocated
+// span to *sysStat.
+//
+// The returned span is fully initialized.
+//
+// h.lock must not be held.
+//
+// allocSpan must be called on the system stack both because it acquires
+// the heap lock and because it must block GC transitions.
+//
+//go:systemstack
+func (h *mheap) allocSpan(npages uintptr, typ spanAllocType, spanclass spanClass) (s *mspan) {
+	// Function-global state.
+	gp := getg()
+	base, scav := uintptr(0), uintptr(0)
+	growth := uintptr(0)
+
+	// On some platforms we need to provide physical page aligned stack
+	// allocations. Where the page size is less than the physical page
+	// size, we already manage to do this by default.
+	needPhysPageAlign := physPageAlignedStacks && typ == spanAllocStack && pageSize < physPageSize
+
+	// If the allocation is small enough, try the page cache!
+	// The page cache does not support aligned allocations, so we cannot use
+	// it if we need to provide a physical page aligned stack allocation.
+	pp := gp.m.p.ptr()
+	if !needPhysPageAlign && pp != nil && npages < pageCachePages/4 {
+		c := &pp.pcache
+
+		// If the cache is empty, refill it.
+		if c.empty() {
+			lock(&h.lock)
+			*c = h.pages.allocToCache()
+			unlock(&h.lock)
+		}
+
+		// Try to allocate from the cache.
+		base, scav = c.alloc(npages)
+		if base != 0 {
+			s = h.tryAllocMSpan()
+			if s != nil {
+				goto HaveSpan
+			}
+			// We have a base but no mspan, so we need
+			// to lock the heap.
+		}
+	}
+
+	// For one reason or another, we couldn't get the
+	// whole job done without the heap lock.
+	lock(&h.lock)
+
+	if needPhysPageAlign {
+		// Overallocate by a physical page to allow for later alignment.
+		extraPages := physPageSize / pageSize
+
+		// Find a big enough region first, but then only allocate the
+		// aligned portion. We can't just allocate and then free the
+		// edges because we need to account for scavenged memory, and
+		// that's difficult with alloc.
+		//
+		// Note that we skip updates to searchAddr here. It's OK if
+		// it's stale and higher than normal; it'll operate correctly,
+		// just come with a performance cost.
+		base, _ = h.pages.find(npages + extraPages)
+		if base == 0 {
+			var ok bool
+			growth, ok = h.grow(npages + extraPages)
+			if !ok {
+				unlock(&h.lock)
+				return nil
+			}
+			base, _ = h.pages.find(npages + extraPages)
+			if base == 0 {
+				throw("grew heap, but no adequate free space found")
+			}
+		}
+		base = alignUp(base, physPageSize)
+		scav = h.pages.allocRange(base, npages)
+	}
+	if base == 0 {
+		// Try to acquire a base address.
+		base, scav = h.pages.alloc(npages)
+		if base == 0 {
+			var ok bool
+			growth, ok = h.grow(npages)
+			if !ok {
+				unlock(&h.lock)
+				return nil
+			}
+			base, scav = h.pages.alloc(npages)
+			if base == 0 {
+				throw("grew heap, but no adequate free space found")
+			}
+		}
+	}
+	if s == nil {
+		// We failed to get an mspan earlier, so grab
+		// one now that we have the heap lock.
+		s = h.allocMSpanLocked()
+	}
+	unlock(&h.lock)
+
+HaveSpan:
+	// At this point, both s != nil and base != 0, and the heap
+	// lock is no longer held. Initialize the span.
+	s.init(base, npages)
+	if h.allocNeedsZero(base, npages) {
+		s.needzero = 1
+	}
+	nbytes := npages * pageSize
+	if typ.manual() {
+		s.manualFreeList = 0
+		s.nelems = 0
+		s.limit = s.base() + s.npages*pageSize
+		s.state.set(mSpanManual)
+	} else {
+		// We must set span properties before the span is published anywhere
+		// since we're not holding the heap lock.
+		s.spanclass = spanclass
+		if sizeclass := spanclass.sizeclass(); sizeclass == 0 {
+			s.elemsize = nbytes
+			s.nelems = 1
+			s.divMul = 0
+		} else {
+			s.elemsize = uintptr(class_to_size[sizeclass])
+			s.nelems = nbytes / s.elemsize
+			s.divMul = class_to_divmagic[sizeclass]
+		}
+
+		// Initialize mark and allocation structures.
+		s.freeindex = 0
+		s.allocCache = ^uint64(0) // all 1s indicating all free.
+		s.gcmarkBits = newMarkBits(s.nelems)
+		s.allocBits = newAllocBits(s.nelems)
+
+		// It's safe to access h.sweepgen without the heap lock because it's
+		// only ever updated with the world stopped and we run on the
+		// systemstack which blocks a STW transition.
+		atomic.Store(&s.sweepgen, h.sweepgen)
+
+		// Now that the span is filled in, set its state. This
+		// is a publication barrier for the other fields in
+		// the span. While valid pointers into this span
+		// should never be visible until the span is returned,
+		// if the garbage collector finds an invalid pointer,
+		// access to the span may race with initialization of
+		// the span. We resolve this race by atomically
+		// setting the state after the span is fully
+		// initialized, and atomically checking the state in
+		// any situation where a pointer is suspect.
+		s.state.set(mSpanInUse)
+	}
+
+	// Decide if we need to scavenge in response to what we just allocated.
+	// Specifically, we track the maximum amount of memory to scavenge of all
+	// the alternatives below, assuming that the maximum satisfies *all*
+	// conditions we check (e.g. if we need to scavenge X to satisfy the
+	// memory limit and Y to satisfy heap-growth scavenging, and Y > X, then
+	// it's fine to pick Y, because the memory limit is still satisfied).
+	//
+	// It's fine to do this after allocating because we expect any scavenged
+	// pages not to get touched until we return. Simultaneously, it's important
+	// to do this before calling sysUsed because that may commit address space.
+	bytesToScavenge := uintptr(0)
+	if limit := gcController.memoryLimit.Load(); go119MemoryLimitSupport && !gcCPULimiter.limiting() {
+		// Assist with scavenging to maintain the memory limit by the amount
+		// that we expect to page in.
+		inuse := gcController.mappedReady.Load()
+		// Be careful about overflow, especially with uintptrs. Even on 32-bit platforms
+		// someone can set a really big memory limit that isn't maxInt64.
+		if uint64(scav)+inuse > uint64(limit) {
+			bytesToScavenge = uintptr(uint64(scav) + inuse - uint64(limit))
+		}
+	}
+	if goal := scavenge.gcPercentGoal.Load(); goal != ^uint64(0) && growth > 0 {
+		// We just caused a heap growth, so scavenge down what will soon be used.
+		// By scavenging inline we deal with the failure to allocate out of
+		// memory fragments by scavenging the memory fragments that are least
+		// likely to be re-used.
+		//
+		// Only bother with this because we're not using a memory limit. We don't
+		// care about heap growths as long as we're under the memory limit, and the
+		// previous check for scaving already handles that.
+		if retained := heapRetained(); retained+uint64(growth) > goal {
+			// The scavenging algorithm requires the heap lock to be dropped so it
+			// can acquire it only sparingly. This is a potentially expensive operation
+			// so it frees up other goroutines to allocate in the meanwhile. In fact,
+			// they can make use of the growth we just created.
+			todo := growth
+			if overage := uintptr(retained + uint64(growth) - goal); todo > overage {
+				todo = overage
+			}
+			if todo > bytesToScavenge {
+				bytesToScavenge = todo
+			}
+		}
+	}
+	// There are a few very limited cirumstances where we won't have a P here.
+	// It's OK to simply skip scavenging in these cases. Something else will notice
+	// and pick up the tab.
+	if pp != nil && bytesToScavenge > 0 {
+		// Measure how long we spent scavenging and add that measurement to the assist
+		// time so we can track it for the GC CPU limiter.
+		//
+		// Limiter event tracking might be disabled if we end up here
+		// while on a mark worker.
+		start := nanotime()
+		track := pp.limiterEvent.start(limiterEventScavengeAssist, start)
+
+		// Scavenge, but back out if the limiter turns on.
+		h.pages.scavenge(bytesToScavenge, func() bool {
+			return gcCPULimiter.limiting()
+		})
+
+		// Finish up accounting.
+		now := nanotime()
+		if track {
+			pp.limiterEvent.stop(limiterEventScavengeAssist, now)
+		}
+		h.pages.scav.assistTime.Add(now - start)
+	}
+
+	// Commit and account for any scavenged memory that the span now owns.
+	if scav != 0 {
+		// sysUsed all the pages that are actually available
+		// in the span since some of them might be scavenged.
+		sysUsed(unsafe.Pointer(base), nbytes, scav)
+		gcController.heapReleased.add(-int64(scav))
+	}
+	// Update stats.
+	gcController.heapFree.add(-int64(nbytes - scav))
+	if typ == spanAllocHeap {
+		gcController.heapInUse.add(int64(nbytes))
+	}
+	// Update consistent stats.
+	stats := memstats.heapStats.acquire()
+	atomic.Xaddint64(&stats.committed, int64(scav))
+	atomic.Xaddint64(&stats.released, -int64(scav))
+	switch typ {
+	case spanAllocHeap:
+		atomic.Xaddint64(&stats.inHeap, int64(nbytes))
+	case spanAllocStack:
+		atomic.Xaddint64(&stats.inStacks, int64(nbytes))
+	case spanAllocPtrScalarBits:
+		atomic.Xaddint64(&stats.inPtrScalarBits, int64(nbytes))
+	case spanAllocWorkBuf:
+		atomic.Xaddint64(&stats.inWorkBufs, int64(nbytes))
+	}
+	memstats.heapStats.release()
+
+	// Publish the span in various locations.
+
+	// This is safe to call without the lock held because the slots
+	// related to this span will only ever be read or modified by
+	// this thread until pointers into the span are published (and
+	// we execute a publication barrier at the end of this function
+	// before that happens) or pageInUse is updated.
+	h.setSpans(s.base(), npages, s)
+
+	if !typ.manual() {
+		// Mark in-use span in arena page bitmap.
+		//
+		// This publishes the span to the page sweeper, so
+		// it's imperative that the span be completely initialized
+		// prior to this line.
+		arena, pageIdx, pageMask := pageIndexOf(s.base())
+		atomic.Or8(&arena.pageInUse[pageIdx], pageMask)
+
+		// Update related page sweeper stats.
+		h.pagesInUse.Add(int64(npages))
+	}
+
+	// Make sure the newly allocated span will be observed
+	// by the GC before pointers into the span are published.
+	publicationBarrier()
+
+	return s
+}
+
+// Try to add at least npage pages of memory to the heap,
+// returning how much the heap grew by and whether it worked.
+//
+// h.lock must be held.
+func (h *mheap) grow(npage uintptr) (uintptr, bool) {
+	assertLockHeld(&h.lock)
+
+	// We must grow the heap in whole palloc chunks.
+	// We call sysMap below but note that because we
+	// round up to pallocChunkPages which is on the order
+	// of MiB (generally >= to the huge page size) we
+	// won't be calling it too much.
+	ask := alignUp(npage, pallocChunkPages) * pageSize
+
+	totalGrowth := uintptr(0)
+	// This may overflow because ask could be very large
+	// and is otherwise unrelated to h.curArena.base.
+	end := h.curArena.base + ask
+	nBase := alignUp(end, physPageSize)
+	if nBase > h.curArena.end || /* overflow */ end < h.curArena.base {
+		// Not enough room in the current arena. Allocate more
+		// arena space. This may not be contiguous with the
+		// current arena, so we have to request the full ask.
+		av, asize := h.sysAlloc(ask)
+		if av == nil {
+			inUse := gcController.heapFree.load() + gcController.heapReleased.load() + gcController.heapInUse.load()
+			print("runtime: out of memory: cannot allocate ", ask, "-byte block (", inUse, " in use)\n")
+			return 0, false
+		}
+
+		if uintptr(av) == h.curArena.end {
+			// The new space is contiguous with the old
+			// space, so just extend the current space.
+			h.curArena.end = uintptr(av) + asize
+		} else {
+			// The new space is discontiguous. Track what
+			// remains of the current space and switch to
+			// the new space. This should be rare.
+			if size := h.curArena.end - h.curArena.base; size != 0 {
+				// Transition this space from Reserved to Prepared and mark it
+				// as released since we'll be able to start using it after updating
+				// the page allocator and releasing the lock at any time.
+				sysMap(unsafe.Pointer(h.curArena.base), size, &gcController.heapReleased)
+				// Update stats.
+				stats := memstats.heapStats.acquire()
+				atomic.Xaddint64(&stats.released, int64(size))
+				memstats.heapStats.release()
+				// Update the page allocator's structures to make this
+				// space ready for allocation.
+				h.pages.grow(h.curArena.base, size)
+				totalGrowth += size
+			}
+			// Switch to the new space.
+			h.curArena.base = uintptr(av)
+			h.curArena.end = uintptr(av) + asize
+		}
+
+		// Recalculate nBase.
+		// We know this won't overflow, because sysAlloc returned
+		// a valid region starting at h.curArena.base which is at
+		// least ask bytes in size.
+		nBase = alignUp(h.curArena.base+ask, physPageSize)
+	}
+
+	// Grow into the current arena.
+	v := h.curArena.base
+	h.curArena.base = nBase
+
+	// Transition the space we're going to use from Reserved to Prepared.
+	//
+	// The allocation is always aligned to the heap arena
+	// size which is always > physPageSize, so its safe to
+	// just add directly to heapReleased.
+	sysMap(unsafe.Pointer(v), nBase-v, &gcController.heapReleased)
+
+	// The memory just allocated counts as both released
+	// and idle, even though it's not yet backed by spans.
+	stats := memstats.heapStats.acquire()
+	atomic.Xaddint64(&stats.released, int64(nBase-v))
+	memstats.heapStats.release()
+
+	// Update the page allocator's structures to make this
+	// space ready for allocation.
+	h.pages.grow(v, nBase-v)
+	totalGrowth += nBase - v
+	return totalGrowth, true
+}
+
+// Free the span back into the heap.
+func (h *mheap) freeSpan(s *mspan) {
+	systemstack(func() {
+		lock(&h.lock)
+		if msanenabled {
+			// Tell msan that this entire span is no longer in use.
+			base := unsafe.Pointer(s.base())
+			bytes := s.npages << _PageShift
+			msanfree(base, bytes)
+		}
+		if asanenabled {
+			// Tell asan that this entire span is no longer in use.
+			base := unsafe.Pointer(s.base())
+			bytes := s.npages << _PageShift
+			asanpoison(base, bytes)
+		}
+		h.freeSpanLocked(s, spanAllocHeap)
+		unlock(&h.lock)
+	})
+}
+
+// freeManual frees a manually-managed span returned by allocManual.
+// typ must be the same as the spanAllocType passed to the allocManual that
+// allocated s.
+//
+// This must only be called when gcphase == _GCoff. See mSpanState for
+// an explanation.
+//
+// freeManual must be called on the system stack because it acquires
+// the heap lock. See mheap for details.
+//
+//go:systemstack
+func (h *mheap) freeManual(s *mspan, typ spanAllocType) {
+	s.needzero = 1
+	lock(&h.lock)
+	h.freeSpanLocked(s, typ)
+	unlock(&h.lock)
+}
+
+func (h *mheap) freeSpanLocked(s *mspan, typ spanAllocType) {
+	assertLockHeld(&h.lock)
+
+	switch s.state.get() {
+	case mSpanManual:
+		if s.allocCount != 0 {
+			throw("mheap.freeSpanLocked - invalid stack free")
+		}
+	case mSpanInUse:
+		if s.allocCount != 0 || s.sweepgen != h.sweepgen {
+			print("mheap.freeSpanLocked - span ", s, " ptr ", hex(s.base()), " allocCount ", s.allocCount, " sweepgen ", s.sweepgen, "/", h.sweepgen, "\n")
+			throw("mheap.freeSpanLocked - invalid free")
+		}
+		h.pagesInUse.Add(-int64(s.npages))
+
+		// Clear in-use bit in arena page bitmap.
+		arena, pageIdx, pageMask := pageIndexOf(s.base())
+		atomic.And8(&arena.pageInUse[pageIdx], ^pageMask)
+	default:
+		throw("mheap.freeSpanLocked - invalid span state")
+	}
+
+	// Update stats.
+	//
+	// Mirrors the code in allocSpan.
+	nbytes := s.npages * pageSize
+	gcController.heapFree.add(int64(nbytes))
+	if typ == spanAllocHeap {
+		gcController.heapInUse.add(-int64(nbytes))
+	}
+	// Update consistent stats.
+	stats := memstats.heapStats.acquire()
+	switch typ {
+	case spanAllocHeap:
+		atomic.Xaddint64(&stats.inHeap, -int64(nbytes))
+	case spanAllocStack:
+		atomic.Xaddint64(&stats.inStacks, -int64(nbytes))
+	case spanAllocPtrScalarBits:
+		atomic.Xaddint64(&stats.inPtrScalarBits, -int64(nbytes))
+	case spanAllocWorkBuf:
+		atomic.Xaddint64(&stats.inWorkBufs, -int64(nbytes))
+	}
+	memstats.heapStats.release()
+
+	// Mark the space as free.
+	h.pages.free(s.base(), s.npages, false)
+
+	// Free the span structure. We no longer have a use for it.
+	s.state.set(mSpanDead)
+	h.freeMSpanLocked(s)
+}
+
+// scavengeAll acquires the heap lock (blocking any additional
+// manipulation of the page allocator) and iterates over the whole
+// heap, scavenging every free page available.
+func (h *mheap) scavengeAll() {
+	// Disallow malloc or panic while holding the heap lock. We do
+	// this here because this is a non-mallocgc entry-point to
+	// the mheap API.
+	gp := getg()
+	gp.m.mallocing++
+
+	released := h.pages.scavenge(^uintptr(0), nil)
+
+	gp.m.mallocing--
+
+	if debug.scavtrace > 0 {
+		printScavTrace(released, true)
+	}
+}
+
+//go:linkname runtime_debug_freeOSMemory runtime/debug.freeOSMemory
+func runtime_debug_freeOSMemory() {
+	GC()
+	systemstack(func() { mheap_.scavengeAll() })
+}
+
+// Initialize a new span with the given start and npages.
+func (span *mspan) init(base uintptr, npages uintptr) {
+	// span is *not* zeroed.
+	span.next = nil
+	span.prev = nil
+	span.list = nil
+	span.startAddr = base
+	span.npages = npages
+	span.allocCount = 0
+	span.spanclass = 0
+	span.elemsize = 0
+	span.speciallock.key = 0
+	span.specials = nil
+	span.needzero = 0
+	span.freeindex = 0
+	span.allocBits = nil
+	span.gcmarkBits = nil
+	span.state.set(mSpanDead)
+	lockInit(&span.speciallock, lockRankMspanSpecial)
+}
+
+func (span *mspan) inList() bool {
+	return span.list != nil
+}
+
+// Initialize an empty doubly-linked list.
+func (list *mSpanList) init() {
+	list.first = nil
+	list.last = nil
+}
+
+func (list *mSpanList) remove(span *mspan) {
+	if span.list != list {
+		print("runtime: failed mSpanList.remove span.npages=", span.npages,
+			" span=", span, " prev=", span.prev, " span.list=", span.list, " list=", list, "\n")
+		throw("mSpanList.remove")
+	}
+	if list.first == span {
+		list.first = span.next
+	} else {
+		span.prev.next = span.next
+	}
+	if list.last == span {
+		list.last = span.prev
+	} else {
+		span.next.prev = span.prev
+	}
+	span.next = nil
+	span.prev = nil
+	span.list = nil
+}
+
+func (list *mSpanList) isEmpty() bool {
+	return list.first == nil
+}
+
+func (list *mSpanList) insert(span *mspan) {
+	if span.next != nil || span.prev != nil || span.list != nil {
+		println("runtime: failed mSpanList.insert", span, span.next, span.prev, span.list)
+		throw("mSpanList.insert")
+	}
+	span.next = list.first
+	if list.first != nil {
+		// The list contains at least one span; link it in.
+		// The last span in the list doesn't change.
+		list.first.prev = span
+	} else {
+		// The list contains no spans, so this is also the last span.
+		list.last = span
+	}
+	list.first = span
+	span.list = list
+}
+
+func (list *mSpanList) insertBack(span *mspan) {
+	if span.next != nil || span.prev != nil || span.list != nil {
+		println("runtime: failed mSpanList.insertBack", span, span.next, span.prev, span.list)
+		throw("mSpanList.insertBack")
+	}
+	span.prev = list.last
+	if list.last != nil {
+		// The list contains at least one span.
+		list.last.next = span
+	} else {
+		// The list contains no spans, so this is also the first span.
+		list.first = span
+	}
+	list.last = span
+	span.list = list
+}
+
+// takeAll removes all spans from other and inserts them at the front
+// of list.
+func (list *mSpanList) takeAll(other *mSpanList) {
+	if other.isEmpty() {
+		return
+	}
+
+	// Reparent everything in other to list.
+	for s := other.first; s != nil; s = s.next {
+		s.list = list
+	}
+
+	// Concatenate the lists.
+	if list.isEmpty() {
+		*list = *other
+	} else {
+		// Neither list is empty. Put other before list.
+		other.last.next = list.first
+		list.first.prev = other.last
+		list.first = other.first
+	}
+
+	other.first, other.last = nil, nil
+}
+
+const (
+	_KindSpecialFinalizer = 1
+	_KindSpecialProfile   = 2
+	// _KindSpecialReachable is a special used for tracking
+	// reachability during testing.
+	_KindSpecialReachable = 3
+	// Note: The finalizer special must be first because if we're freeing
+	// an object, a finalizer special will cause the freeing operation
+	// to abort, and we want to keep the other special records around
+	// if that happens.
+)
+
+//go:notinheap
+type special struct {
+	next   *special // linked list in span
+	offset uint16   // span offset of object
+	kind   byte     // kind of special
+}
+
+// spanHasSpecials marks a span as having specials in the arena bitmap.
+func spanHasSpecials(s *mspan) {
+	arenaPage := (s.base() / pageSize) % pagesPerArena
+	ai := arenaIndex(s.base())
+	ha := mheap_.arenas[ai.l1()][ai.l2()]
+	atomic.Or8(&ha.pageSpecials[arenaPage/8], uint8(1)<<(arenaPage%8))
+}
+
+// spanHasNoSpecials marks a span as having no specials in the arena bitmap.
+func spanHasNoSpecials(s *mspan) {
+	arenaPage := (s.base() / pageSize) % pagesPerArena
+	ai := arenaIndex(s.base())
+	ha := mheap_.arenas[ai.l1()][ai.l2()]
+	atomic.And8(&ha.pageSpecials[arenaPage/8], ^(uint8(1) << (arenaPage % 8)))
+}
+
+// Adds the special record s to the list of special records for
+// the object p. All fields of s should be filled in except for
+// offset & next, which this routine will fill in.
+// Returns true if the special was successfully added, false otherwise.
+// (The add will fail only if a record with the same p and s->kind
+// already exists.)
+func addspecial(p unsafe.Pointer, s *special) bool {
+	span := spanOfHeap(uintptr(p))
+	if span == nil {
+		throw("addspecial on invalid pointer")
+	}
+
+	// Ensure that the span is swept.
+	// Sweeping accesses the specials list w/o locks, so we have
+	// to synchronize with it. And it's just much safer.
+	mp := acquirem()
+	span.ensureSwept()
+
+	offset := uintptr(p) - span.base()
+	kind := s.kind
+
+	lock(&span.speciallock)
+
+	// Find splice point, check for existing record.
+	t := &span.specials
+	for {
+		x := *t
+		if x == nil {
+			break
+		}
+		if offset == uintptr(x.offset) && kind == x.kind {
+			unlock(&span.speciallock)
+			releasem(mp)
+			return false // already exists
+		}
+		if offset < uintptr(x.offset) || (offset == uintptr(x.offset) && kind < x.kind) {
+			break
+		}
+		t = &x.next
+	}
+
+	// Splice in record, fill in offset.
+	s.offset = uint16(offset)
+	s.next = *t
+	*t = s
+	spanHasSpecials(span)
+	unlock(&span.speciallock)
+	releasem(mp)
+
+	return true
+}
+
+// Removes the Special record of the given kind for the object p.
+// Returns the record if the record existed, nil otherwise.
+// The caller must FixAlloc_Free the result.
+func removespecial(p unsafe.Pointer, kind uint8) *special {
+	span := spanOfHeap(uintptr(p))
+	if span == nil {
+		throw("removespecial on invalid pointer")
+	}
+
+	// Ensure that the span is swept.
+	// Sweeping accesses the specials list w/o locks, so we have
+	// to synchronize with it. And it's just much safer.
+	mp := acquirem()
+	span.ensureSwept()
+
+	offset := uintptr(p) - span.base()
+
+	var result *special
+	lock(&span.speciallock)
+	t := &span.specials
+	for {
+		s := *t
+		if s == nil {
+			break
+		}
+		// This function is used for finalizers only, so we don't check for
+		// "interior" specials (p must be exactly equal to s->offset).
+		if offset == uintptr(s.offset) && kind == s.kind {
+			*t = s.next
+			result = s
+			break
+		}
+		t = &s.next
+	}
+	if span.specials == nil {
+		spanHasNoSpecials(span)
+	}
+	unlock(&span.speciallock)
+	releasem(mp)
+	return result
+}
+
+// The described object has a finalizer set for it.
+//
+// specialfinalizer is allocated from non-GC'd memory, so any heap
+// pointers must be specially handled.
+//
+//go:notinheap
+type specialfinalizer struct {
+	special special
+	fn      *funcval // May be a heap pointer.
+	nret    uintptr
+	fint    *_type   // May be a heap pointer, but always live.
+	ot      *ptrtype // May be a heap pointer, but always live.
+}
+
+// Adds a finalizer to the object p. Returns true if it succeeded.
+func addfinalizer(p unsafe.Pointer, f *funcval, nret uintptr, fint *_type, ot *ptrtype) bool {
+	lock(&mheap_.speciallock)
+	s := (*specialfinalizer)(mheap_.specialfinalizeralloc.alloc())
+	unlock(&mheap_.speciallock)
+	s.special.kind = _KindSpecialFinalizer
+	s.fn = f
+	s.nret = nret
+	s.fint = fint
+	s.ot = ot
+	if addspecial(p, &s.special) {
+		// This is responsible for maintaining the same
+		// GC-related invariants as markrootSpans in any
+		// situation where it's possible that markrootSpans
+		// has already run but mark termination hasn't yet.
+		if gcphase != _GCoff {
+			base, _, _ := findObject(uintptr(p), 0, 0)
+			mp := acquirem()
+			gcw := &mp.p.ptr().gcw
+			// Mark everything reachable from the object
+			// so it's retained for the finalizer.
+			scanobject(base, gcw)
+			// Mark the finalizer itself, since the
+			// special isn't part of the GC'd heap.
+			scanblock(uintptr(unsafe.Pointer(&s.fn)), goarch.PtrSize, &oneptrmask[0], gcw, nil)
+			releasem(mp)
+		}
+		return true
+	}
+
+	// There was an old finalizer
+	lock(&mheap_.speciallock)
+	mheap_.specialfinalizeralloc.free(unsafe.Pointer(s))
+	unlock(&mheap_.speciallock)
+	return false
+}
+
+// Removes the finalizer (if any) from the object p.
+func removefinalizer(p unsafe.Pointer) {
+	s := (*specialfinalizer)(unsafe.Pointer(removespecial(p, _KindSpecialFinalizer)))
+	if s == nil {
+		return // there wasn't a finalizer to remove
+	}
+	lock(&mheap_.speciallock)
+	mheap_.specialfinalizeralloc.free(unsafe.Pointer(s))
+	unlock(&mheap_.speciallock)
+}
+
+// The described object is being heap profiled.
+//
+//go:notinheap
+type specialprofile struct {
+	special special
+	b       *bucket
+}
+
+// Set the heap profile bucket associated with addr to b.
+func setprofilebucket(p unsafe.Pointer, b *bucket) {
+	lock(&mheap_.speciallock)
+	s := (*specialprofile)(mheap_.specialprofilealloc.alloc())
+	unlock(&mheap_.speciallock)
+	s.special.kind = _KindSpecialProfile
+	s.b = b
+	if !addspecial(p, &s.special) {
+		throw("setprofilebucket: profile already set")
+	}
+}
+
+// specialReachable tracks whether an object is reachable on the next
+// GC cycle. This is used by testing.
+type specialReachable struct {
+	special   special
+	done      bool
+	reachable bool
+}
+
+// specialsIter helps iterate over specials lists.
+type specialsIter struct {
+	pprev **special
+	s     *special
+}
+
+func newSpecialsIter(span *mspan) specialsIter {
+	return specialsIter{&span.specials, span.specials}
+}
+
+func (i *specialsIter) valid() bool {
+	return i.s != nil
+}
+
+func (i *specialsIter) next() {
+	i.pprev = &i.s.next
+	i.s = *i.pprev
+}
+
+// unlinkAndNext removes the current special from the list and moves
+// the iterator to the next special. It returns the unlinked special.
+func (i *specialsIter) unlinkAndNext() *special {
+	cur := i.s
+	i.s = cur.next
+	*i.pprev = i.s
+	return cur
+}
+
+// freeSpecial performs any cleanup on special s and deallocates it.
+// s must already be unlinked from the specials list.
+func freeSpecial(s *special, p unsafe.Pointer, size uintptr) {
+	switch s.kind {
+	case _KindSpecialFinalizer:
+		sf := (*specialfinalizer)(unsafe.Pointer(s))
+		queuefinalizer(p, sf.fn, sf.nret, sf.fint, sf.ot)
+		lock(&mheap_.speciallock)
+		mheap_.specialfinalizeralloc.free(unsafe.Pointer(sf))
+		unlock(&mheap_.speciallock)
+	case _KindSpecialProfile:
+		sp := (*specialprofile)(unsafe.Pointer(s))
+		mProf_Free(sp.b, size)
+		lock(&mheap_.speciallock)
+		mheap_.specialprofilealloc.free(unsafe.Pointer(sp))
+		unlock(&mheap_.speciallock)
+	case _KindSpecialReachable:
+		sp := (*specialReachable)(unsafe.Pointer(s))
+		sp.done = true
+		// The creator frees these.
+	default:
+		throw("bad special kind")
+		panic("not reached")
+	}
+}
+
+// gcBits is an alloc/mark bitmap. This is always used as *gcBits.
+//
+//go:notinheap
+type gcBits uint8
+
+// bytep returns a pointer to the n'th byte of b.
+func (b *gcBits) bytep(n uintptr) *uint8 {
+	return addb((*uint8)(b), n)
+}
+
+// bitp returns a pointer to the byte containing bit n and a mask for
+// selecting that bit from *bytep.
+func (b *gcBits) bitp(n uintptr) (bytep *uint8, mask uint8) {
+	return b.bytep(n / 8), 1 << (n % 8)
+}
+
+const gcBitsChunkBytes = uintptr(64 << 10)
+const gcBitsHeaderBytes = unsafe.Sizeof(gcBitsHeader{})
+
+type gcBitsHeader struct {
+	free uintptr // free is the index into bits of the next free byte.
+	next uintptr // *gcBits triggers recursive type bug. (issue 14620)
+}
+
+//go:notinheap
+type gcBitsArena struct {
+	// gcBitsHeader // side step recursive type bug (issue 14620) by including fields by hand.
+	free uintptr // free is the index into bits of the next free byte; read/write atomically
+	next *gcBitsArena
+	bits [gcBitsChunkBytes - gcBitsHeaderBytes]gcBits
+}
+
+var gcBitsArenas struct {
+	lock     mutex
+	free     *gcBitsArena
+	next     *gcBitsArena // Read atomically. Write atomically under lock.
+	current  *gcBitsArena
+	previous *gcBitsArena
+}
+
+// tryAlloc allocates from b or returns nil if b does not have enough room.
+// This is safe to call concurrently.
+func (b *gcBitsArena) tryAlloc(bytes uintptr) *gcBits {
+	if b == nil || atomic.Loaduintptr(&b.free)+bytes > uintptr(len(b.bits)) {
+		return nil
+	}
+	// Try to allocate from this block.
+	end := atomic.Xadduintptr(&b.free, bytes)
+	if end > uintptr(len(b.bits)) {
+		return nil
+	}
+	// There was enough room.
+	start := end - bytes
+	return &b.bits[start]
+}
+
+// newMarkBits returns a pointer to 8 byte aligned bytes
+// to be used for a span's mark bits.
+func newMarkBits(nelems uintptr) *gcBits {
+	blocksNeeded := uintptr((nelems + 63) / 64)
+	bytesNeeded := blocksNeeded * 8
+
+	// Try directly allocating from the current head arena.
+	head := (*gcBitsArena)(atomic.Loadp(unsafe.Pointer(&gcBitsArenas.next)))
+	if p := head.tryAlloc(bytesNeeded); p != nil {
+		return p
+	}
+
+	// There's not enough room in the head arena. We may need to
+	// allocate a new arena.
+	lock(&gcBitsArenas.lock)
+	// Try the head arena again, since it may have changed. Now
+	// that we hold the lock, the list head can't change, but its
+	// free position still can.
+	if p := gcBitsArenas.next.tryAlloc(bytesNeeded); p != nil {
+		unlock(&gcBitsArenas.lock)
+		return p
+	}
+
+	// Allocate a new arena. This may temporarily drop the lock.
+	fresh := newArenaMayUnlock()
+	// If newArenaMayUnlock dropped the lock, another thread may
+	// have put a fresh arena on the "next" list. Try allocating
+	// from next again.
+	if p := gcBitsArenas.next.tryAlloc(bytesNeeded); p != nil {
+		// Put fresh back on the free list.
+		// TODO: Mark it "already zeroed"
+		fresh.next = gcBitsArenas.free
+		gcBitsArenas.free = fresh
+		unlock(&gcBitsArenas.lock)
+		return p
+	}
+
+	// Allocate from the fresh arena. We haven't linked it in yet, so
+	// this cannot race and is guaranteed to succeed.
+	p := fresh.tryAlloc(bytesNeeded)
+	if p == nil {
+		throw("markBits overflow")
+	}
+
+	// Add the fresh arena to the "next" list.
+	fresh.next = gcBitsArenas.next
+	atomic.StorepNoWB(unsafe.Pointer(&gcBitsArenas.next), unsafe.Pointer(fresh))
+
+	unlock(&gcBitsArenas.lock)
+	return p
+}
+
+// newAllocBits returns a pointer to 8 byte aligned bytes
+// to be used for this span's alloc bits.
+// newAllocBits is used to provide newly initialized spans
+// allocation bits. For spans not being initialized the
+// mark bits are repurposed as allocation bits when
+// the span is swept.
+func newAllocBits(nelems uintptr) *gcBits {
+	return newMarkBits(nelems)
+}
+
+// nextMarkBitArenaEpoch establishes a new epoch for the arenas
+// holding the mark bits. The arenas are named relative to the
+// current GC cycle which is demarcated by the call to finishweep_m.
+//
+// All current spans have been swept.
+// During that sweep each span allocated room for its gcmarkBits in
+// gcBitsArenas.next block. gcBitsArenas.next becomes the gcBitsArenas.current
+// where the GC will mark objects and after each span is swept these bits
+// will be used to allocate objects.
+// gcBitsArenas.current becomes gcBitsArenas.previous where the span's
+// gcAllocBits live until all the spans have been swept during this GC cycle.
+// The span's sweep extinguishes all the references to gcBitsArenas.previous
+// by pointing gcAllocBits into the gcBitsArenas.current.
+// The gcBitsArenas.previous is released to the gcBitsArenas.free list.
+func nextMarkBitArenaEpoch() {
+	lock(&gcBitsArenas.lock)
+	if gcBitsArenas.previous != nil {
+		if gcBitsArenas.free == nil {
+			gcBitsArenas.free = gcBitsArenas.previous
+		} else {
+			// Find end of previous arenas.
+			last := gcBitsArenas.previous
+			for last = gcBitsArenas.previous; last.next != nil; last = last.next {
+			}
+			last.next = gcBitsArenas.free
+			gcBitsArenas.free = gcBitsArenas.previous
+		}
+	}
+	gcBitsArenas.previous = gcBitsArenas.current
+	gcBitsArenas.current = gcBitsArenas.next
+	atomic.StorepNoWB(unsafe.Pointer(&gcBitsArenas.next), nil) // newMarkBits calls newArena when needed
+	unlock(&gcBitsArenas.lock)
+}
+
+// newArenaMayUnlock allocates and zeroes a gcBits arena.
+// The caller must hold gcBitsArena.lock. This may temporarily release it.
+func newArenaMayUnlock() *gcBitsArena {
+	var result *gcBitsArena
+	if gcBitsArenas.free == nil {
+		unlock(&gcBitsArenas.lock)
+		result = (*gcBitsArena)(sysAlloc(gcBitsChunkBytes, &memstats.gcMiscSys))
+		if result == nil {
+			throw("runtime: cannot allocate memory")
+		}
+		lock(&gcBitsArenas.lock)
+	} else {
+		result = gcBitsArenas.free
+		gcBitsArenas.free = gcBitsArenas.free.next
+		memclrNoHeapPointers(unsafe.Pointer(result), gcBitsChunkBytes)
+	}
+	result.next = nil
+	// If result.bits is not 8 byte aligned adjust index so
+	// that &result.bits[result.free] is 8 byte aligned.
+	if uintptr(unsafe.Offsetof(gcBitsArena{}.bits))&7 == 0 {
+		result.free = 0
+	} else {
+		result.free = 8 - (uintptr(unsafe.Pointer(&result.bits[0])) & 7)
+	}
+	return result
+}
diff --git a/contrib/go/_std_1.19/src/runtime/mpagealloc.go b/contrib/go/_std_1.19/src/runtime/mpagealloc.go
new file mode 100644
index 0000000000..5de25cfe00
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/mpagealloc.go
@@ -0,0 +1,1013 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Page allocator.
+//
+// The page allocator manages mapped pages (defined by pageSize, NOT
+// physPageSize) for allocation and re-use. It is embedded into mheap.
+//
+// Pages are managed using a bitmap that is sharded into chunks.
+// In the bitmap, 1 means in-use, and 0 means free. The bitmap spans the
+// process's address space. Chunks are managed in a sparse-array-style structure
+// similar to mheap.arenas, since the bitmap may be large on some systems.
+//
+// The bitmap is efficiently searched by using a radix tree in combination
+// with fast bit-wise intrinsics. Allocation is performed using an address-ordered
+// first-fit approach.
+//
+// Each entry in the radix tree is a summary that describes three properties of
+// a particular region of the address space: the number of contiguous free pages
+// at the start and end of the region it represents, and the maximum number of
+// contiguous free pages found anywhere in that region.
+//
+// Each level of the radix tree is stored as one contiguous array, which represents
+// a different granularity of subdivision of the processes' address space. Thus, this
+// radix tree is actually implicit in these large arrays, as opposed to having explicit
+// dynamically-allocated pointer-based node structures. Naturally, these arrays may be
+// quite large for system with large address spaces, so in these cases they are mapped
+// into memory as needed. The leaf summaries of the tree correspond to a bitmap chunk.
+//
+// The root level (referred to as L0 and index 0 in pageAlloc.summary) has each
+// summary represent the largest section of address space (16 GiB on 64-bit systems),
+// with each subsequent level representing successively smaller subsections until we
+// reach the finest granularity at the leaves, a chunk.
+//
+// More specifically, each summary in each level (except for leaf summaries)
+// represents some number of entries in the following level. For example, each
+// summary in the root level may represent a 16 GiB region of address space,
+// and in the next level there could be 8 corresponding entries which represent 2
+// GiB subsections of that 16 GiB region, each of which could correspond to 8
+// entries in the next level which each represent 256 MiB regions, and so on.
+//
+// Thus, this design only scales to heaps so large, but can always be extended to
+// larger heaps by simply adding levels to the radix tree, which mostly costs
+// additional virtual address space. The choice of managing large arrays also means
+// that a large amount of virtual address space may be reserved by the runtime.
+
+package runtime
+
+import (
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+const (
+	// The size of a bitmap chunk, i.e. the amount of bits (that is, pages) to consider
+	// in the bitmap at once.
+	pallocChunkPages    = 1 << logPallocChunkPages
+	pallocChunkBytes    = pallocChunkPages * pageSize
+	logPallocChunkPages = 9
+	logPallocChunkBytes = logPallocChunkPages + pageShift
+
+	// The number of radix bits for each level.
+	//
+	// The value of 3 is chosen such that the block of summaries we need to scan at
+	// each level fits in 64 bytes (2^3 summaries * 8 bytes per summary), which is
+	// close to the L1 cache line width on many systems. Also, a value of 3 fits 4 tree
+	// levels perfectly into the 21-bit pallocBits summary field at the root level.
+	//
+	// The following equation explains how each of the constants relate:
+	// summaryL0Bits + (summaryLevels-1)*summaryLevelBits + logPallocChunkBytes = heapAddrBits
+	//
+	// summaryLevels is an architecture-dependent value defined in mpagealloc_*.go.
+	summaryLevelBits = 3
+	summaryL0Bits    = heapAddrBits - logPallocChunkBytes - (summaryLevels-1)*summaryLevelBits
+
+	// pallocChunksL2Bits is the number of bits of the chunk index number
+	// covered by the second level of the chunks map.
+	//
+	// See (*pageAlloc).chunks for more details. Update the documentation
+	// there should this change.
+	pallocChunksL2Bits  = heapAddrBits - logPallocChunkBytes - pallocChunksL1Bits
+	pallocChunksL1Shift = pallocChunksL2Bits
+)
+
+// maxSearchAddr returns the maximum searchAddr value, which indicates
+// that the heap has no free space.
+//
+// This function exists just to make it clear that this is the maximum address
+// for the page allocator's search space. See maxOffAddr for details.
+//
+// It's a function (rather than a variable) because it needs to be
+// usable before package runtime's dynamic initialization is complete.
+// See #51913 for details.
+func maxSearchAddr() offAddr { return maxOffAddr }
+
+// Global chunk index.
+//
+// Represents an index into the leaf level of the radix tree.
+// Similar to arenaIndex, except instead of arenas, it divides the address
+// space into chunks.
+type chunkIdx uint
+
+// chunkIndex returns the global index of the palloc chunk containing the
+// pointer p.
+func chunkIndex(p uintptr) chunkIdx {
+	return chunkIdx((p - arenaBaseOffset) / pallocChunkBytes)
+}
+
+// chunkIndex returns the base address of the palloc chunk at index ci.
+func chunkBase(ci chunkIdx) uintptr {
+	return uintptr(ci)*pallocChunkBytes + arenaBaseOffset
+}
+
+// chunkPageIndex computes the index of the page that contains p,
+// relative to the chunk which contains p.
+func chunkPageIndex(p uintptr) uint {
+	return uint(p % pallocChunkBytes / pageSize)
+}
+
+// l1 returns the index into the first level of (*pageAlloc).chunks.
+func (i chunkIdx) l1() uint {
+	if pallocChunksL1Bits == 0 {
+		// Let the compiler optimize this away if there's no
+		// L1 map.
+		return 0
+	} else {
+		return uint(i) >> pallocChunksL1Shift
+	}
+}
+
+// l2 returns the index into the second level of (*pageAlloc).chunks.
+func (i chunkIdx) l2() uint {
+	if pallocChunksL1Bits == 0 {
+		return uint(i)
+	} else {
+		return uint(i) & (1<<pallocChunksL2Bits - 1)
+	}
+}
+
+// offAddrToLevelIndex converts an address in the offset address space
+// to the index into summary[level] containing addr.
+func offAddrToLevelIndex(level int, addr offAddr) int {
+	return int((addr.a - arenaBaseOffset) >> levelShift[level])
+}
+
+// levelIndexToOffAddr converts an index into summary[level] into
+// the corresponding address in the offset address space.
+func levelIndexToOffAddr(level, idx int) offAddr {
+	return offAddr{(uintptr(idx) << levelShift[level]) + arenaBaseOffset}
+}
+
+// addrsToSummaryRange converts base and limit pointers into a range
+// of entries for the given summary level.
+//
+// The returned range is inclusive on the lower bound and exclusive on
+// the upper bound.
+func addrsToSummaryRange(level int, base, limit uintptr) (lo int, hi int) {
+	// This is slightly more nuanced than just a shift for the exclusive
+	// upper-bound. Note that the exclusive upper bound may be within a
+	// summary at this level, meaning if we just do the obvious computation
+	// hi will end up being an inclusive upper bound. Unfortunately, just
+	// adding 1 to that is too broad since we might be on the very edge
+	// of a summary's max page count boundary for this level
+	// (1 << levelLogPages[level]). So, make limit an inclusive upper bound
+	// then shift, then add 1, so we get an exclusive upper bound at the end.
+	lo = int((base - arenaBaseOffset) >> levelShift[level])
+	hi = int(((limit-1)-arenaBaseOffset)>>levelShift[level]) + 1
+	return
+}
+
+// blockAlignSummaryRange aligns indices into the given level to that
+// level's block width (1 << levelBits[level]). It assumes lo is inclusive
+// and hi is exclusive, and so aligns them down and up respectively.
+func blockAlignSummaryRange(level int, lo, hi int) (int, int) {
+	e := uintptr(1) << levelBits[level]
+	return int(alignDown(uintptr(lo), e)), int(alignUp(uintptr(hi), e))
+}
+
+type pageAlloc struct {
+	// Radix tree of summaries.
+	//
+	// Each slice's cap represents the whole memory reservation.
+	// Each slice's len reflects the allocator's maximum known
+	// mapped heap address for that level.
+	//
+	// The backing store of each summary level is reserved in init
+	// and may or may not be committed in grow (small address spaces
+	// may commit all the memory in init).
+	//
+	// The purpose of keeping len <= cap is to enforce bounds checks
+	// on the top end of the slice so that instead of an unknown
+	// runtime segmentation fault, we get a much friendlier out-of-bounds
+	// error.
+	//
+	// To iterate over a summary level, use inUse to determine which ranges
+	// are currently available. Otherwise one might try to access
+	// memory which is only Reserved which may result in a hard fault.
+	//
+	// We may still get segmentation faults < len since some of that
+	// memory may not be committed yet.
+	summary [summaryLevels][]pallocSum
+
+	// chunks is a slice of bitmap chunks.
+	//
+	// The total size of chunks is quite large on most 64-bit platforms
+	// (O(GiB) or more) if flattened, so rather than making one large mapping
+	// (which has problems on some platforms, even when PROT_NONE) we use a
+	// two-level sparse array approach similar to the arena index in mheap.
+	//
+	// To find the chunk containing a memory address `a`, do:
+	//   chunkOf(chunkIndex(a))
+	//
+	// Below is a table describing the configuration for chunks for various
+	// heapAddrBits supported by the runtime.
+	//
+	// heapAddrBits | L1 Bits | L2 Bits | L2 Entry Size
+	// ------------------------------------------------
+	// 32           | 0       | 10      | 128 KiB
+	// 33 (iOS)     | 0       | 11      | 256 KiB
+	// 48           | 13      | 13      | 1 MiB
+	//
+	// There's no reason to use the L1 part of chunks on 32-bit, the
+	// address space is small so the L2 is small. For platforms with a
+	// 48-bit address space, we pick the L1 such that the L2 is 1 MiB
+	// in size, which is a good balance between low granularity without
+	// making the impact on BSS too high (note the L1 is stored directly
+	// in pageAlloc).
+	//
+	// To iterate over the bitmap, use inUse to determine which ranges
+	// are currently available. Otherwise one might iterate over unused
+	// ranges.
+	//
+	// Protected by mheapLock.
+	//
+	// TODO(mknyszek): Consider changing the definition of the bitmap
+	// such that 1 means free and 0 means in-use so that summaries and
+	// the bitmaps align better on zero-values.
+	chunks [1 << pallocChunksL1Bits]*[1 << pallocChunksL2Bits]pallocData
+
+	// The address to start an allocation search with. It must never
+	// point to any memory that is not contained in inUse, i.e.
+	// inUse.contains(searchAddr.addr()) must always be true. The one
+	// exception to this rule is that it may take on the value of
+	// maxOffAddr to indicate that the heap is exhausted.
+	//
+	// We guarantee that all valid heap addresses below this value
+	// are allocated and not worth searching.
+	searchAddr offAddr
+
+	// start and end represent the chunk indices
+	// which pageAlloc knows about. It assumes
+	// chunks in the range [start, end) are
+	// currently ready to use.
+	start, end chunkIdx
+
+	// inUse is a slice of ranges of address space which are
+	// known by the page allocator to be currently in-use (passed
+	// to grow).
+	//
+	// This field is currently unused on 32-bit architectures but
+	// is harmless to track. We care much more about having a
+	// contiguous heap in these cases and take additional measures
+	// to ensure that, so in nearly all cases this should have just
+	// 1 element.
+	//
+	// All access is protected by the mheapLock.
+	inUse addrRanges
+
+	_ uint32 // Align scav so it's easier to reason about alignment within scav.
+
+	// scav stores the scavenger state.
+	scav struct {
+		// index is an efficient index of chunks that have pages available to
+		// scavenge.
+		index scavengeIndex
+
+		// released is the amount of memory released this generation.
+		//
+		// Updated atomically.
+		released uintptr
+
+		_ uint32 // Align assistTime for atomics on 32-bit platforms.
+
+		// scavengeAssistTime is the time spent scavenging in the last GC cycle.
+		//
+		// This is reset once a GC cycle ends.
+		assistTime atomic.Int64
+	}
+
+	// mheap_.lock. This level of indirection makes it possible
+	// to test pageAlloc indepedently of the runtime allocator.
+	mheapLock *mutex
+
+	// sysStat is the runtime memstat to update when new system
+	// memory is committed by the pageAlloc for allocation metadata.
+	sysStat *sysMemStat
+
+	// summaryMappedReady is the number of bytes mapped in the Ready state
+	// in the summary structure. Used only for testing currently.
+	//
+	// Protected by mheapLock.
+	summaryMappedReady uintptr
+
+	// Whether or not this struct is being used in tests.
+	test bool
+}
+
+func (p *pageAlloc) init(mheapLock *mutex, sysStat *sysMemStat) {
+	if levelLogPages[0] > logMaxPackedValue {
+		// We can't represent 1<<levelLogPages[0] pages, the maximum number
+		// of pages we need to represent at the root level, in a summary, which
+		// is a big problem. Throw.
+		print("runtime: root level max pages = ", 1<<levelLogPages[0], "\n")
+		print("runtime: summary max pages = ", maxPackedValue, "\n")
+		throw("root level max pages doesn't fit in summary")
+	}
+	p.sysStat = sysStat
+
+	// Initialize p.inUse.
+	p.inUse.init(sysStat)
+
+	// System-dependent initialization.
+	p.sysInit()
+
+	// Start with the searchAddr in a state indicating there's no free memory.
+	p.searchAddr = maxSearchAddr()
+
+	// Set the mheapLock.
+	p.mheapLock = mheapLock
+}
+
+// tryChunkOf returns the bitmap data for the given chunk.
+//
+// Returns nil if the chunk data has not been mapped.
+func (p *pageAlloc) tryChunkOf(ci chunkIdx) *pallocData {
+	l2 := p.chunks[ci.l1()]
+	if l2 == nil {
+		return nil
+	}
+	return &l2[ci.l2()]
+}
+
+// chunkOf returns the chunk at the given chunk index.
+//
+// The chunk index must be valid or this method may throw.
+func (p *pageAlloc) chunkOf(ci chunkIdx) *pallocData {
+	return &p.chunks[ci.l1()][ci.l2()]
+}
+
+// grow sets up the metadata for the address range [base, base+size).
+// It may allocate metadata, in which case *p.sysStat will be updated.
+//
+// p.mheapLock must be held.
+func (p *pageAlloc) grow(base, size uintptr) {
+	assertLockHeld(p.mheapLock)
+
+	// Round up to chunks, since we can't deal with increments smaller
+	// than chunks. Also, sysGrow expects aligned values.
+	limit := alignUp(base+size, pallocChunkBytes)
+	base = alignDown(base, pallocChunkBytes)
+
+	// Grow the summary levels in a system-dependent manner.
+	// We just update a bunch of additional metadata here.
+	p.sysGrow(base, limit)
+
+	// Update p.start and p.end.
+	// If no growth happened yet, start == 0. This is generally
+	// safe since the zero page is unmapped.
+	firstGrowth := p.start == 0
+	start, end := chunkIndex(base), chunkIndex(limit)
+	if firstGrowth || start < p.start {
+		p.start = start
+	}
+	if end > p.end {
+		p.end = end
+	}
+	// Note that [base, limit) will never overlap with any existing
+	// range inUse because grow only ever adds never-used memory
+	// regions to the page allocator.
+	p.inUse.add(makeAddrRange(base, limit))
+
+	// A grow operation is a lot like a free operation, so if our
+	// chunk ends up below p.searchAddr, update p.searchAddr to the
+	// new address, just like in free.
+	if b := (offAddr{base}); b.lessThan(p.searchAddr) {
+		p.searchAddr = b
+	}
+
+	// Add entries into chunks, which is sparse, if needed. Then,
+	// initialize the bitmap.
+	//
+	// Newly-grown memory is always considered scavenged.
+	// Set all the bits in the scavenged bitmaps high.
+	for c := chunkIndex(base); c < chunkIndex(limit); c++ {
+		if p.chunks[c.l1()] == nil {
+			// Create the necessary l2 entry.
+			//
+			// Store it atomically to avoid races with readers which
+			// don't acquire the heap lock.
+			r := sysAlloc(unsafe.Sizeof(*p.chunks[0]), p.sysStat)
+			if r == nil {
+				throw("pageAlloc: out of memory")
+			}
+			atomic.StorepNoWB(unsafe.Pointer(&p.chunks[c.l1()]), r)
+		}
+		p.chunkOf(c).scavenged.setRange(0, pallocChunkPages)
+	}
+
+	// Update summaries accordingly. The grow acts like a free, so
+	// we need to ensure this newly-free memory is visible in the
+	// summaries.
+	p.update(base, size/pageSize, true, false)
+}
+
+// update updates heap metadata. It must be called each time the bitmap
+// is updated.
+//
+// If contig is true, update does some optimizations assuming that there was
+// a contiguous allocation or free between addr and addr+npages. alloc indicates
+// whether the operation performed was an allocation or a free.
+//
+// p.mheapLock must be held.
+func (p *pageAlloc) update(base, npages uintptr, contig, alloc bool) {
+	assertLockHeld(p.mheapLock)
+
+	// base, limit, start, and end are inclusive.
+	limit := base + npages*pageSize - 1
+	sc, ec := chunkIndex(base), chunkIndex(limit)
+
+	// Handle updating the lowest level first.
+	if sc == ec {
+		// Fast path: the allocation doesn't span more than one chunk,
+		// so update this one and if the summary didn't change, return.
+		x := p.summary[len(p.summary)-1][sc]
+		y := p.chunkOf(sc).summarize()
+		if x == y {
+			return
+		}
+		p.summary[len(p.summary)-1][sc] = y
+	} else if contig {
+		// Slow contiguous path: the allocation spans more than one chunk
+		// and at least one summary is guaranteed to change.
+		summary := p.summary[len(p.summary)-1]
+
+		// Update the summary for chunk sc.
+		summary[sc] = p.chunkOf(sc).summarize()
+
+		// Update the summaries for chunks in between, which are
+		// either totally allocated or freed.
+		whole := p.summary[len(p.summary)-1][sc+1 : ec]
+		if alloc {
+			// Should optimize into a memclr.
+			for i := range whole {
+				whole[i] = 0
+			}
+		} else {
+			for i := range whole {
+				whole[i] = freeChunkSum
+			}
+		}
+
+		// Update the summary for chunk ec.
+		summary[ec] = p.chunkOf(ec).summarize()
+	} else {
+		// Slow general path: the allocation spans more than one chunk
+		// and at least one summary is guaranteed to change.
+		//
+		// We can't assume a contiguous allocation happened, so walk over
+		// every chunk in the range and manually recompute the summary.
+		summary := p.summary[len(p.summary)-1]
+		for c := sc; c <= ec; c++ {
+			summary[c] = p.chunkOf(c).summarize()
+		}
+	}
+
+	// Walk up the radix tree and update the summaries appropriately.
+	changed := true
+	for l := len(p.summary) - 2; l >= 0 && changed; l-- {
+		// Update summaries at level l from summaries at level l+1.
+		changed = false
+
+		// "Constants" for the previous level which we
+		// need to compute the summary from that level.
+		logEntriesPerBlock := levelBits[l+1]
+		logMaxPages := levelLogPages[l+1]
+
+		// lo and hi describe all the parts of the level we need to look at.
+		lo, hi := addrsToSummaryRange(l, base, limit+1)
+
+		// Iterate over each block, updating the corresponding summary in the less-granular level.
+		for i := lo; i < hi; i++ {
+			children := p.summary[l+1][i<<logEntriesPerBlock : (i+1)<<logEntriesPerBlock]
+			sum := mergeSummaries(children, logMaxPages)
+			old := p.summary[l][i]
+			if old != sum {
+				changed = true
+				p.summary[l][i] = sum
+			}
+		}
+	}
+}
+
+// allocRange marks the range of memory [base, base+npages*pageSize) as
+// allocated. It also updates the summaries to reflect the newly-updated
+// bitmap.
+//
+// Returns the amount of scavenged memory in bytes present in the
+// allocated range.
+//
+// p.mheapLock must be held.
+func (p *pageAlloc) allocRange(base, npages uintptr) uintptr {
+	assertLockHeld(p.mheapLock)
+
+	limit := base + npages*pageSize - 1
+	sc, ec := chunkIndex(base), chunkIndex(limit)
+	si, ei := chunkPageIndex(base), chunkPageIndex(limit)
+
+	scav := uint(0)
+	if sc == ec {
+		// The range doesn't cross any chunk boundaries.
+		chunk := p.chunkOf(sc)
+		scav += chunk.scavenged.popcntRange(si, ei+1-si)
+		chunk.allocRange(si, ei+1-si)
+	} else {
+		// The range crosses at least one chunk boundary.
+		chunk := p.chunkOf(sc)
+		scav += chunk.scavenged.popcntRange(si, pallocChunkPages-si)
+		chunk.allocRange(si, pallocChunkPages-si)
+		for c := sc + 1; c < ec; c++ {
+			chunk := p.chunkOf(c)
+			scav += chunk.scavenged.popcntRange(0, pallocChunkPages)
+			chunk.allocAll()
+		}
+		chunk = p.chunkOf(ec)
+		scav += chunk.scavenged.popcntRange(0, ei+1)
+		chunk.allocRange(0, ei+1)
+	}
+	p.update(base, npages, true, true)
+	return uintptr(scav) * pageSize
+}
+
+// findMappedAddr returns the smallest mapped offAddr that is
+// >= addr. That is, if addr refers to mapped memory, then it is
+// returned. If addr is higher than any mapped region, then
+// it returns maxOffAddr.
+//
+// p.mheapLock must be held.
+func (p *pageAlloc) findMappedAddr(addr offAddr) offAddr {
+	assertLockHeld(p.mheapLock)
+
+	// If we're not in a test, validate first by checking mheap_.arenas.
+	// This is a fast path which is only safe to use outside of testing.
+	ai := arenaIndex(addr.addr())
+	if p.test || mheap_.arenas[ai.l1()] == nil || mheap_.arenas[ai.l1()][ai.l2()] == nil {
+		vAddr, ok := p.inUse.findAddrGreaterEqual(addr.addr())
+		if ok {
+			return offAddr{vAddr}
+		} else {
+			// The candidate search address is greater than any
+			// known address, which means we definitely have no
+			// free memory left.
+			return maxOffAddr
+		}
+	}
+	return addr
+}
+
+// find searches for the first (address-ordered) contiguous free region of
+// npages in size and returns a base address for that region.
+//
+// It uses p.searchAddr to prune its search and assumes that no palloc chunks
+// below chunkIndex(p.searchAddr) contain any free memory at all.
+//
+// find also computes and returns a candidate p.searchAddr, which may or
+// may not prune more of the address space than p.searchAddr already does.
+// This candidate is always a valid p.searchAddr.
+//
+// find represents the slow path and the full radix tree search.
+//
+// Returns a base address of 0 on failure, in which case the candidate
+// searchAddr returned is invalid and must be ignored.
+//
+// p.mheapLock must be held.
+func (p *pageAlloc) find(npages uintptr) (uintptr, offAddr) {
+	assertLockHeld(p.mheapLock)
+
+	// Search algorithm.
+	//
+	// This algorithm walks each level l of the radix tree from the root level
+	// to the leaf level. It iterates over at most 1 << levelBits[l] of entries
+	// in a given level in the radix tree, and uses the summary information to
+	// find either:
+	//  1) That a given subtree contains a large enough contiguous region, at
+	//     which point it continues iterating on the next level, or
+	//  2) That there are enough contiguous boundary-crossing bits to satisfy
+	//     the allocation, at which point it knows exactly where to start
+	//     allocating from.
+	//
+	// i tracks the index into the current level l's structure for the
+	// contiguous 1 << levelBits[l] entries we're actually interested in.
+	//
+	// NOTE: Technically this search could allocate a region which crosses
+	// the arenaBaseOffset boundary, which when arenaBaseOffset != 0, is
+	// a discontinuity. However, the only way this could happen is if the
+	// page at the zero address is mapped, and this is impossible on
+	// every system we support where arenaBaseOffset != 0. So, the
+	// discontinuity is already encoded in the fact that the OS will never
+	// map the zero page for us, and this function doesn't try to handle
+	// this case in any way.
+
+	// i is the beginning of the block of entries we're searching at the
+	// current level.
+	i := 0
+
+	// firstFree is the region of address space that we are certain to
+	// find the first free page in the heap. base and bound are the inclusive
+	// bounds of this window, and both are addresses in the linearized, contiguous
+	// view of the address space (with arenaBaseOffset pre-added). At each level,
+	// this window is narrowed as we find the memory region containing the
+	// first free page of memory. To begin with, the range reflects the
+	// full process address space.
+	//
+	// firstFree is updated by calling foundFree each time free space in the
+	// heap is discovered.
+	//
+	// At the end of the search, base.addr() is the best new
+	// searchAddr we could deduce in this search.
+	firstFree := struct {
+		base, bound offAddr
+	}{
+		base:  minOffAddr,
+		bound: maxOffAddr,
+	}
+	// foundFree takes the given address range [addr, addr+size) and
+	// updates firstFree if it is a narrower range. The input range must
+	// either be fully contained within firstFree or not overlap with it
+	// at all.
+	//
+	// This way, we'll record the first summary we find with any free
+	// pages on the root level and narrow that down if we descend into
+	// that summary. But as soon as we need to iterate beyond that summary
+	// in a level to find a large enough range, we'll stop narrowing.
+	foundFree := func(addr offAddr, size uintptr) {
+		if firstFree.base.lessEqual(addr) && addr.add(size-1).lessEqual(firstFree.bound) {
+			// This range fits within the current firstFree window, so narrow
+			// down the firstFree window to the base and bound of this range.
+			firstFree.base = addr
+			firstFree.bound = addr.add(size - 1)
+		} else if !(addr.add(size-1).lessThan(firstFree.base) || firstFree.bound.lessThan(addr)) {
+			// This range only partially overlaps with the firstFree range,
+			// so throw.
+			print("runtime: addr = ", hex(addr.addr()), ", size = ", size, "\n")
+			print("runtime: base = ", hex(firstFree.base.addr()), ", bound = ", hex(firstFree.bound.addr()), "\n")
+			throw("range partially overlaps")
+		}
+	}
+
+	// lastSum is the summary which we saw on the previous level that made us
+	// move on to the next level. Used to print additional information in the
+	// case of a catastrophic failure.
+	// lastSumIdx is that summary's index in the previous level.
+	lastSum := packPallocSum(0, 0, 0)
+	lastSumIdx := -1
+
+nextLevel:
+	for l := 0; l < len(p.summary); l++ {
+		// For the root level, entriesPerBlock is the whole level.
+		entriesPerBlock := 1 << levelBits[l]
+		logMaxPages := levelLogPages[l]
+
+		// We've moved into a new level, so let's update i to our new
+		// starting index. This is a no-op for level 0.
+		i <<= levelBits[l]
+
+		// Slice out the block of entries we care about.
+		entries := p.summary[l][i : i+entriesPerBlock]
+
+		// Determine j0, the first index we should start iterating from.
+		// The searchAddr may help us eliminate iterations if we followed the
+		// searchAddr on the previous level or we're on the root leve, in which
+		// case the searchAddr should be the same as i after levelShift.
+		j0 := 0
+		if searchIdx := offAddrToLevelIndex(l, p.searchAddr); searchIdx&^(entriesPerBlock-1) == i {
+			j0 = searchIdx & (entriesPerBlock - 1)
+		}
+
+		// Run over the level entries looking for
+		// a contiguous run of at least npages either
+		// within an entry or across entries.
+		//
+		// base contains the page index (relative to
+		// the first entry's first page) of the currently
+		// considered run of consecutive pages.
+		//
+		// size contains the size of the currently considered
+		// run of consecutive pages.
+		var base, size uint
+		for j := j0; j < len(entries); j++ {
+			sum := entries[j]
+			if sum == 0 {
+				// A full entry means we broke any streak and
+				// that we should skip it altogether.
+				size = 0
+				continue
+			}
+
+			// We've encountered a non-zero summary which means
+			// free memory, so update firstFree.
+			foundFree(levelIndexToOffAddr(l, i+j), (uintptr(1)<<logMaxPages)*pageSize)
+
+			s := sum.start()
+			if size+s >= uint(npages) {
+				// If size == 0 we don't have a run yet,
+				// which means base isn't valid. So, set
+				// base to the first page in this block.
+				if size == 0 {
+					base = uint(j) << logMaxPages
+				}
+				// We hit npages; we're done!
+				size += s
+				break
+			}
+			if sum.max() >= uint(npages) {
+				// The entry itself contains npages contiguous
+				// free pages, so continue on the next level
+				// to find that run.
+				i += j
+				lastSumIdx = i
+				lastSum = sum
+				continue nextLevel
+			}
+			if size == 0 || s < 1<<logMaxPages {
+				// We either don't have a current run started, or this entry
+				// isn't totally free (meaning we can't continue the current
+				// one), so try to begin a new run by setting size and base
+				// based on sum.end.
+				size = sum.end()
+				base = uint(j+1)<<logMaxPages - size
+				continue
+			}
+			// The entry is completely free, so continue the run.
+			size += 1 << logMaxPages
+		}
+		if size >= uint(npages) {
+			// We found a sufficiently large run of free pages straddling
+			// some boundary, so compute the address and return it.
+			addr := levelIndexToOffAddr(l, i).add(uintptr(base) * pageSize).addr()
+			return addr, p.findMappedAddr(firstFree.base)
+		}
+		if l == 0 {
+			// We're at level zero, so that means we've exhausted our search.
+			return 0, maxSearchAddr()
+		}
+
+		// We're not at level zero, and we exhausted the level we were looking in.
+		// This means that either our calculations were wrong or the level above
+		// lied to us. In either case, dump some useful state and throw.
+		print("runtime: summary[", l-1, "][", lastSumIdx, "] = ", lastSum.start(), ", ", lastSum.max(), ", ", lastSum.end(), "\n")
+		print("runtime: level = ", l, ", npages = ", npages, ", j0 = ", j0, "\n")
+		print("runtime: p.searchAddr = ", hex(p.searchAddr.addr()), ", i = ", i, "\n")
+		print("runtime: levelShift[level] = ", levelShift[l], ", levelBits[level] = ", levelBits[l], "\n")
+		for j := 0; j < len(entries); j++ {
+			sum := entries[j]
+			print("runtime: summary[", l, "][", i+j, "] = (", sum.start(), ", ", sum.max(), ", ", sum.end(), ")\n")
+		}
+		throw("bad summary data")
+	}
+
+	// Since we've gotten to this point, that means we haven't found a
+	// sufficiently-sized free region straddling some boundary (chunk or larger).
+	// This means the last summary we inspected must have had a large enough "max"
+	// value, so look inside the chunk to find a suitable run.
+	//
+	// After iterating over all levels, i must contain a chunk index which
+	// is what the final level represents.
+	ci := chunkIdx(i)
+	j, searchIdx := p.chunkOf(ci).find(npages, 0)
+	if j == ^uint(0) {
+		// We couldn't find any space in this chunk despite the summaries telling
+		// us it should be there. There's likely a bug, so dump some state and throw.
+		sum := p.summary[len(p.summary)-1][i]
+		print("runtime: summary[", len(p.summary)-1, "][", i, "] = (", sum.start(), ", ", sum.max(), ", ", sum.end(), ")\n")
+		print("runtime: npages = ", npages, "\n")
+		throw("bad summary data")
+	}
+
+	// Compute the address at which the free space starts.
+	addr := chunkBase(ci) + uintptr(j)*pageSize
+
+	// Since we actually searched the chunk, we may have
+	// found an even narrower free window.
+	searchAddr := chunkBase(ci) + uintptr(searchIdx)*pageSize
+	foundFree(offAddr{searchAddr}, chunkBase(ci+1)-searchAddr)
+	return addr, p.findMappedAddr(firstFree.base)
+}
+
+// alloc allocates npages worth of memory from the page heap, returning the base
+// address for the allocation and the amount of scavenged memory in bytes
+// contained in the region [base address, base address + npages*pageSize).
+//
+// Returns a 0 base address on failure, in which case other returned values
+// should be ignored.
+//
+// p.mheapLock must be held.
+//
+// Must run on the system stack because p.mheapLock must be held.
+//
+//go:systemstack
+func (p *pageAlloc) alloc(npages uintptr) (addr uintptr, scav uintptr) {
+	assertLockHeld(p.mheapLock)
+
+	// If the searchAddr refers to a region which has a higher address than
+	// any known chunk, then we know we're out of memory.
+	if chunkIndex(p.searchAddr.addr()) >= p.end {
+		return 0, 0
+	}
+
+	// If npages has a chance of fitting in the chunk where the searchAddr is,
+	// search it directly.
+	searchAddr := minOffAddr
+	if pallocChunkPages-chunkPageIndex(p.searchAddr.addr()) >= uint(npages) {
+		// npages is guaranteed to be no greater than pallocChunkPages here.
+		i := chunkIndex(p.searchAddr.addr())
+		if max := p.summary[len(p.summary)-1][i].max(); max >= uint(npages) {
+			j, searchIdx := p.chunkOf(i).find(npages, chunkPageIndex(p.searchAddr.addr()))
+			if j == ^uint(0) {
+				print("runtime: max = ", max, ", npages = ", npages, "\n")
+				print("runtime: searchIdx = ", chunkPageIndex(p.searchAddr.addr()), ", p.searchAddr = ", hex(p.searchAddr.addr()), "\n")
+				throw("bad summary data")
+			}
+			addr = chunkBase(i) + uintptr(j)*pageSize
+			searchAddr = offAddr{chunkBase(i) + uintptr(searchIdx)*pageSize}
+			goto Found
+		}
+	}
+	// We failed to use a searchAddr for one reason or another, so try
+	// the slow path.
+	addr, searchAddr = p.find(npages)
+	if addr == 0 {
+		if npages == 1 {
+			// We failed to find a single free page, the smallest unit
+			// of allocation. This means we know the heap is completely
+			// exhausted. Otherwise, the heap still might have free
+			// space in it, just not enough contiguous space to
+			// accommodate npages.
+			p.searchAddr = maxSearchAddr()
+		}
+		return 0, 0
+	}
+Found:
+	// Go ahead and actually mark the bits now that we have an address.
+	scav = p.allocRange(addr, npages)
+
+	// If we found a higher searchAddr, we know that all the
+	// heap memory before that searchAddr in an offset address space is
+	// allocated, so bump p.searchAddr up to the new one.
+	if p.searchAddr.lessThan(searchAddr) {
+		p.searchAddr = searchAddr
+	}
+	return addr, scav
+}
+
+// free returns npages worth of memory starting at base back to the page heap.
+//
+// p.mheapLock must be held.
+//
+// Must run on the system stack because p.mheapLock must be held.
+//
+//go:systemstack
+func (p *pageAlloc) free(base, npages uintptr, scavenged bool) {
+	assertLockHeld(p.mheapLock)
+
+	// If we're freeing pages below the p.searchAddr, update searchAddr.
+	if b := (offAddr{base}); b.lessThan(p.searchAddr) {
+		p.searchAddr = b
+	}
+	limit := base + npages*pageSize - 1
+	if !scavenged {
+		p.scav.index.mark(base, limit+1)
+	}
+	if npages == 1 {
+		// Fast path: we're clearing a single bit, and we know exactly
+		// where it is, so mark it directly.
+		i := chunkIndex(base)
+		p.chunkOf(i).free1(chunkPageIndex(base))
+	} else {
+		// Slow path: we're clearing more bits so we may need to iterate.
+		sc, ec := chunkIndex(base), chunkIndex(limit)
+		si, ei := chunkPageIndex(base), chunkPageIndex(limit)
+
+		if sc == ec {
+			// The range doesn't cross any chunk boundaries.
+			p.chunkOf(sc).free(si, ei+1-si)
+		} else {
+			// The range crosses at least one chunk boundary.
+			p.chunkOf(sc).free(si, pallocChunkPages-si)
+			for c := sc + 1; c < ec; c++ {
+				p.chunkOf(c).freeAll()
+			}
+			p.chunkOf(ec).free(0, ei+1)
+		}
+	}
+	p.update(base, npages, true, false)
+}
+
+const (
+	pallocSumBytes = unsafe.Sizeof(pallocSum(0))
+
+	// maxPackedValue is the maximum value that any of the three fields in
+	// the pallocSum may take on.
+	maxPackedValue    = 1 << logMaxPackedValue
+	logMaxPackedValue = logPallocChunkPages + (summaryLevels-1)*summaryLevelBits
+
+	freeChunkSum = pallocSum(uint64(pallocChunkPages) |
+		uint64(pallocChunkPages<<logMaxPackedValue) |
+		uint64(pallocChunkPages<<(2*logMaxPackedValue)))
+)
+
+// pallocSum is a packed summary type which packs three numbers: start, max,
+// and end into a single 8-byte value. Each of these values are a summary of
+// a bitmap and are thus counts, each of which may have a maximum value of
+// 2^21 - 1, or all three may be equal to 2^21. The latter case is represented
+// by just setting the 64th bit.
+type pallocSum uint64
+
+// packPallocSum takes a start, max, and end value and produces a pallocSum.
+func packPallocSum(start, max, end uint) pallocSum {
+	if max == maxPackedValue {
+		return pallocSum(uint64(1 << 63))
+	}
+	return pallocSum((uint64(start) & (maxPackedValue - 1)) |
+		((uint64(max) & (maxPackedValue - 1)) << logMaxPackedValue) |
+		((uint64(end) & (maxPackedValue - 1)) << (2 * logMaxPackedValue)))
+}
+
+// start extracts the start value from a packed sum.
+func (p pallocSum) start() uint {
+	if uint64(p)&uint64(1<<63) != 0 {
+		return maxPackedValue
+	}
+	return uint(uint64(p) & (maxPackedValue - 1))
+}
+
+// max extracts the max value from a packed sum.
+func (p pallocSum) max() uint {
+	if uint64(p)&uint64(1<<63) != 0 {
+		return maxPackedValue
+	}
+	return uint((uint64(p) >> logMaxPackedValue) & (maxPackedValue - 1))
+}
+
+// end extracts the end value from a packed sum.
+func (p pallocSum) end() uint {
+	if uint64(p)&uint64(1<<63) != 0 {
+		return maxPackedValue
+	}
+	return uint((uint64(p) >> (2 * logMaxPackedValue)) & (maxPackedValue - 1))
+}
+
+// unpack unpacks all three values from the summary.
+func (p pallocSum) unpack() (uint, uint, uint) {
+	if uint64(p)&uint64(1<<63) != 0 {
+		return maxPackedValue, maxPackedValue, maxPackedValue
+	}
+	return uint(uint64(p) & (maxPackedValue - 1)),
+		uint((uint64(p) >> logMaxPackedValue) & (maxPackedValue - 1)),
+		uint((uint64(p) >> (2 * logMaxPackedValue)) & (maxPackedValue - 1))
+}
+
+// mergeSummaries merges consecutive summaries which may each represent at
+// most 1 << logMaxPagesPerSum pages each together into one.
+func mergeSummaries(sums []pallocSum, logMaxPagesPerSum uint) pallocSum {
+	// Merge the summaries in sums into one.
+	//
+	// We do this by keeping a running summary representing the merged
+	// summaries of sums[:i] in start, max, and end.
+	start, max, end := sums[0].unpack()
+	for i := 1; i < len(sums); i++ {
+		// Merge in sums[i].
+		si, mi, ei := sums[i].unpack()
+
+		// Merge in sums[i].start only if the running summary is
+		// completely free, otherwise this summary's start
+		// plays no role in the combined sum.
+		if start == uint(i)<<logMaxPagesPerSum {
+			start += si
+		}
+
+		// Recompute the max value of the running sum by looking
+		// across the boundary between the running sum and sums[i]
+		// and at the max sums[i], taking the greatest of those two
+		// and the max of the running sum.
+		if end+si > max {
+			max = end + si
+		}
+		if mi > max {
+			max = mi
+		}
+
+		// Merge in end by checking if this new summary is totally
+		// free. If it is, then we want to extend the running sum's
+		// end by the new summary. If not, then we have some alloc'd
+		// pages in there and we just want to take the end value in
+		// sums[i].
+		if ei == 1<<logMaxPagesPerSum {
+			end += 1 << logMaxPagesPerSum
+		} else {
+			end = ei
+		}
+	}
+	return packPallocSum(start, max, end)
+}
diff --git a/contrib/go/_std_1.19/src/runtime/mpagealloc_64bit.go b/contrib/go/_std_1.19/src/runtime/mpagealloc_64bit.go
new file mode 100644
index 0000000000..371c1fb31c
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/mpagealloc_64bit.go
@@ -0,0 +1,257 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build amd64 || arm64 || loong64 || mips64 || mips64le || ppc64 || ppc64le || riscv64 || s390x
+
+package runtime
+
+import (
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+const (
+	// The number of levels in the radix tree.
+	summaryLevels = 5
+
+	// Constants for testing.
+	pageAlloc32Bit = 0
+	pageAlloc64Bit = 1
+
+	// Number of bits needed to represent all indices into the L1 of the
+	// chunks map.
+	//
+	// See (*pageAlloc).chunks for more details. Update the documentation
+	// there should this number change.
+	pallocChunksL1Bits = 13
+)
+
+// levelBits is the number of bits in the radix for a given level in the super summary
+// structure.
+//
+// The sum of all the entries of levelBits should equal heapAddrBits.
+var levelBits = [summaryLevels]uint{
+	summaryL0Bits,
+	summaryLevelBits,
+	summaryLevelBits,
+	summaryLevelBits,
+	summaryLevelBits,
+}
+
+// levelShift is the number of bits to shift to acquire the radix for a given level
+// in the super summary structure.
+//
+// With levelShift, one can compute the index of the summary at level l related to a
+// pointer p by doing:
+//
+//	p >> levelShift[l]
+var levelShift = [summaryLevels]uint{
+	heapAddrBits - summaryL0Bits,
+	heapAddrBits - summaryL0Bits - 1*summaryLevelBits,
+	heapAddrBits - summaryL0Bits - 2*summaryLevelBits,
+	heapAddrBits - summaryL0Bits - 3*summaryLevelBits,
+	heapAddrBits - summaryL0Bits - 4*summaryLevelBits,
+}
+
+// levelLogPages is log2 the maximum number of runtime pages in the address space
+// a summary in the given level represents.
+//
+// The leaf level always represents exactly log2 of 1 chunk's worth of pages.
+var levelLogPages = [summaryLevels]uint{
+	logPallocChunkPages + 4*summaryLevelBits,
+	logPallocChunkPages + 3*summaryLevelBits,
+	logPallocChunkPages + 2*summaryLevelBits,
+	logPallocChunkPages + 1*summaryLevelBits,
+	logPallocChunkPages,
+}
+
+// sysInit performs architecture-dependent initialization of fields
+// in pageAlloc. pageAlloc should be uninitialized except for sysStat
+// if any runtime statistic should be updated.
+func (p *pageAlloc) sysInit() {
+	// Reserve memory for each level. This will get mapped in
+	// as R/W by setArenas.
+	for l, shift := range levelShift {
+		entries := 1 << (heapAddrBits - shift)
+
+		// Reserve b bytes of memory anywhere in the address space.
+		b := alignUp(uintptr(entries)*pallocSumBytes, physPageSize)
+		r := sysReserve(nil, b)
+		if r == nil {
+			throw("failed to reserve page summary memory")
+		}
+
+		// Put this reservation into a slice.
+		sl := notInHeapSlice{(*notInHeap)(r), 0, entries}
+		p.summary[l] = *(*[]pallocSum)(unsafe.Pointer(&sl))
+	}
+
+	// Set up the scavenge index.
+	nbytes := uintptr(1<<heapAddrBits) / pallocChunkBytes / 8
+	r := sysReserve(nil, nbytes)
+	sl := notInHeapSlice{(*notInHeap)(r), int(nbytes), int(nbytes)}
+	p.scav.index.chunks = *(*[]atomic.Uint8)(unsafe.Pointer(&sl))
+}
+
+// sysGrow performs architecture-dependent operations on heap
+// growth for the page allocator, such as mapping in new memory
+// for summaries. It also updates the length of the slices in
+// [.summary.
+//
+// base is the base of the newly-added heap memory and limit is
+// the first address past the end of the newly-added heap memory.
+// Both must be aligned to pallocChunkBytes.
+//
+// The caller must update p.start and p.end after calling sysGrow.
+func (p *pageAlloc) sysGrow(base, limit uintptr) {
+	if base%pallocChunkBytes != 0 || limit%pallocChunkBytes != 0 {
+		print("runtime: base = ", hex(base), ", limit = ", hex(limit), "\n")
+		throw("sysGrow bounds not aligned to pallocChunkBytes")
+	}
+
+	// addrRangeToSummaryRange converts a range of addresses into a range
+	// of summary indices which must be mapped to support those addresses
+	// in the summary range.
+	addrRangeToSummaryRange := func(level int, r addrRange) (int, int) {
+		sumIdxBase, sumIdxLimit := addrsToSummaryRange(level, r.base.addr(), r.limit.addr())
+		return blockAlignSummaryRange(level, sumIdxBase, sumIdxLimit)
+	}
+
+	// summaryRangeToSumAddrRange converts a range of indices in any
+	// level of p.summary into page-aligned addresses which cover that
+	// range of indices.
+	summaryRangeToSumAddrRange := func(level, sumIdxBase, sumIdxLimit int) addrRange {
+		baseOffset := alignDown(uintptr(sumIdxBase)*pallocSumBytes, physPageSize)
+		limitOffset := alignUp(uintptr(sumIdxLimit)*pallocSumBytes, physPageSize)
+		base := unsafe.Pointer(&p.summary[level][0])
+		return addrRange{
+			offAddr{uintptr(add(base, baseOffset))},
+			offAddr{uintptr(add(base, limitOffset))},
+		}
+	}
+
+	// addrRangeToSumAddrRange is a convienience function that converts
+	// an address range r to the address range of the given summary level
+	// that stores the summaries for r.
+	addrRangeToSumAddrRange := func(level int, r addrRange) addrRange {
+		sumIdxBase, sumIdxLimit := addrRangeToSummaryRange(level, r)
+		return summaryRangeToSumAddrRange(level, sumIdxBase, sumIdxLimit)
+	}
+
+	// Find the first inUse index which is strictly greater than base.
+	//
+	// Because this function will never be asked remap the same memory
+	// twice, this index is effectively the index at which we would insert
+	// this new growth, and base will never overlap/be contained within
+	// any existing range.
+	//
+	// This will be used to look at what memory in the summary array is already
+	// mapped before and after this new range.
+	inUseIndex := p.inUse.findSucc(base)
+
+	// Walk up the radix tree and map summaries in as needed.
+	for l := range p.summary {
+		// Figure out what part of the summary array this new address space needs.
+		needIdxBase, needIdxLimit := addrRangeToSummaryRange(l, makeAddrRange(base, limit))
+
+		// Update the summary slices with a new upper-bound. This ensures
+		// we get tight bounds checks on at least the top bound.
+		//
+		// We must do this regardless of whether we map new memory.
+		if needIdxLimit > len(p.summary[l]) {
+			p.summary[l] = p.summary[l][:needIdxLimit]
+		}
+
+		// Compute the needed address range in the summary array for level l.
+		need := summaryRangeToSumAddrRange(l, needIdxBase, needIdxLimit)
+
+		// Prune need down to what needs to be newly mapped. Some parts of it may
+		// already be mapped by what inUse describes due to page alignment requirements
+		// for mapping. prune's invariants are guaranteed by the fact that this
+		// function will never be asked to remap the same memory twice.
+		if inUseIndex > 0 {
+			need = need.subtract(addrRangeToSumAddrRange(l, p.inUse.ranges[inUseIndex-1]))
+		}
+		if inUseIndex < len(p.inUse.ranges) {
+			need = need.subtract(addrRangeToSumAddrRange(l, p.inUse.ranges[inUseIndex]))
+		}
+		// It's possible that after our pruning above, there's nothing new to map.
+		if need.size() == 0 {
+			continue
+		}
+
+		// Map and commit need.
+		sysMap(unsafe.Pointer(need.base.addr()), need.size(), p.sysStat)
+		sysUsed(unsafe.Pointer(need.base.addr()), need.size(), need.size())
+		p.summaryMappedReady += need.size()
+	}
+
+	// Update the scavenge index.
+	p.summaryMappedReady += p.scav.index.grow(base, limit, p.sysStat)
+}
+
+// grow increases the index's backing store in response to a heap growth.
+//
+// Returns the amount of memory added to sysStat.
+func (s *scavengeIndex) grow(base, limit uintptr, sysStat *sysMemStat) uintptr {
+	if base%pallocChunkBytes != 0 || limit%pallocChunkBytes != 0 {
+		print("runtime: base = ", hex(base), ", limit = ", hex(limit), "\n")
+		throw("sysGrow bounds not aligned to pallocChunkBytes")
+	}
+	// Map and commit the pieces of chunks that we need.
+	//
+	// We always map the full range of the minimum heap address to the
+	// maximum heap address. We don't do this for the summary structure
+	// because it's quite large and a discontiguous heap could cause a
+	// lot of memory to be used. In this situation, the worst case overhead
+	// is in the single-digit MiB if we map the whole thing.
+	//
+	// The base address of the backing store is always page-aligned,
+	// because it comes from the OS, so it's sufficient to align the
+	// index.
+	haveMin := s.min.Load()
+	haveMax := s.max.Load()
+	needMin := int32(alignDown(uintptr(chunkIndex(base)/8), physPageSize))
+	needMax := int32(alignUp(uintptr((chunkIndex(limit)+7)/8), physPageSize))
+	// Extend the range down to what we have, if there's no overlap.
+	if needMax < haveMin {
+		needMax = haveMin
+	}
+	if needMin > haveMax {
+		needMin = haveMax
+	}
+	have := makeAddrRange(
+		// Avoid a panic from indexing one past the last element.
+		uintptr(unsafe.Pointer(&s.chunks[0]))+uintptr(haveMin),
+		uintptr(unsafe.Pointer(&s.chunks[0]))+uintptr(haveMax),
+	)
+	need := makeAddrRange(
+		// Avoid a panic from indexing one past the last element.
+		uintptr(unsafe.Pointer(&s.chunks[0]))+uintptr(needMin),
+		uintptr(unsafe.Pointer(&s.chunks[0]))+uintptr(needMax),
+	)
+	// Subtract any overlap from rounding. We can't re-map memory because
+	// it'll be zeroed.
+	need = need.subtract(have)
+
+	// If we've got something to map, map it, and update the slice bounds.
+	if need.size() != 0 {
+		sysMap(unsafe.Pointer(need.base.addr()), need.size(), sysStat)
+		sysUsed(unsafe.Pointer(need.base.addr()), need.size(), need.size())
+		// Update the indices only after the new memory is valid.
+		if haveMin == 0 || needMin < haveMin {
+			s.min.Store(needMin)
+		}
+		if haveMax == 0 || needMax > haveMax {
+			s.max.Store(needMax)
+		}
+	}
+	// Update minHeapIdx. Note that even if there's no mapping work to do,
+	// we may still have a new, lower minimum heap address.
+	minHeapIdx := s.minHeapIdx.Load()
+	if baseIdx := int32(chunkIndex(base) / 8); minHeapIdx == 0 || baseIdx < minHeapIdx {
+		s.minHeapIdx.Store(baseIdx)
+	}
+	return need.size()
+}
diff --git a/contrib/go/_std_1.19/src/runtime/mpagecache.go b/contrib/go/_std_1.19/src/runtime/mpagecache.go
new file mode 100644
index 0000000000..5bad4f789a
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/mpagecache.go
@@ -0,0 +1,177 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"runtime/internal/sys"
+	"unsafe"
+)
+
+const pageCachePages = 8 * unsafe.Sizeof(pageCache{}.cache)
+
+// pageCache represents a per-p cache of pages the allocator can
+// allocate from without a lock. More specifically, it represents
+// a pageCachePages*pageSize chunk of memory with 0 or more free
+// pages in it.
+type pageCache struct {
+	base  uintptr // base address of the chunk
+	cache uint64  // 64-bit bitmap representing free pages (1 means free)
+	scav  uint64  // 64-bit bitmap representing scavenged pages (1 means scavenged)
+}
+
+// empty returns true if the pageCache has any free pages, and false
+// otherwise.
+func (c *pageCache) empty() bool {
+	return c.cache == 0
+}
+
+// alloc allocates npages from the page cache and is the main entry
+// point for allocation.
+//
+// Returns a base address and the amount of scavenged memory in the
+// allocated region in bytes.
+//
+// Returns a base address of zero on failure, in which case the
+// amount of scavenged memory should be ignored.
+func (c *pageCache) alloc(npages uintptr) (uintptr, uintptr) {
+	if c.cache == 0 {
+		return 0, 0
+	}
+	if npages == 1 {
+		i := uintptr(sys.TrailingZeros64(c.cache))
+		scav := (c.scav >> i) & 1
+		c.cache &^= 1 << i // set bit to mark in-use
+		c.scav &^= 1 << i  // clear bit to mark unscavenged
+		return c.base + i*pageSize, uintptr(scav) * pageSize
+	}
+	return c.allocN(npages)
+}
+
+// allocN is a helper which attempts to allocate npages worth of pages
+// from the cache. It represents the general case for allocating from
+// the page cache.
+//
+// Returns a base address and the amount of scavenged memory in the
+// allocated region in bytes.
+func (c *pageCache) allocN(npages uintptr) (uintptr, uintptr) {
+	i := findBitRange64(c.cache, uint(npages))
+	if i >= 64 {
+		return 0, 0
+	}
+	mask := ((uint64(1) << npages) - 1) << i
+	scav := sys.OnesCount64(c.scav & mask)
+	c.cache &^= mask // mark in-use bits
+	c.scav &^= mask  // clear scavenged bits
+	return c.base + uintptr(i*pageSize), uintptr(scav) * pageSize
+}
+
+// flush empties out unallocated free pages in the given cache
+// into s. Then, it clears the cache, such that empty returns
+// true.
+//
+// p.mheapLock must be held.
+//
+// Must run on the system stack because p.mheapLock must be held.
+//
+//go:systemstack
+func (c *pageCache) flush(p *pageAlloc) {
+	assertLockHeld(p.mheapLock)
+
+	if c.empty() {
+		return
+	}
+	ci := chunkIndex(c.base)
+	pi := chunkPageIndex(c.base)
+
+	// This method is called very infrequently, so just do the
+	// slower, safer thing by iterating over each bit individually.
+	for i := uint(0); i < 64; i++ {
+		if c.cache&(1<<i) != 0 {
+			p.chunkOf(ci).free1(pi + i)
+		}
+		if c.scav&(1<<i) != 0 {
+			p.chunkOf(ci).scavenged.setRange(pi+i, 1)
+		}
+	}
+	// Since this is a lot like a free, we need to make sure
+	// we update the searchAddr just like free does.
+	if b := (offAddr{c.base}); b.lessThan(p.searchAddr) {
+		p.searchAddr = b
+	}
+	p.update(c.base, pageCachePages, false, false)
+	*c = pageCache{}
+}
+
+// allocToCache acquires a pageCachePages-aligned chunk of free pages which
+// may not be contiguous, and returns a pageCache structure which owns the
+// chunk.
+//
+// p.mheapLock must be held.
+//
+// Must run on the system stack because p.mheapLock must be held.
+//
+//go:systemstack
+func (p *pageAlloc) allocToCache() pageCache {
+	assertLockHeld(p.mheapLock)
+
+	// If the searchAddr refers to a region which has a higher address than
+	// any known chunk, then we know we're out of memory.
+	if chunkIndex(p.searchAddr.addr()) >= p.end {
+		return pageCache{}
+	}
+	c := pageCache{}
+	ci := chunkIndex(p.searchAddr.addr()) // chunk index
+	var chunk *pallocData
+	if p.summary[len(p.summary)-1][ci] != 0 {
+		// Fast path: there's free pages at or near the searchAddr address.
+		chunk = p.chunkOf(ci)
+		j, _ := chunk.find(1, chunkPageIndex(p.searchAddr.addr()))
+		if j == ^uint(0) {
+			throw("bad summary data")
+		}
+		c = pageCache{
+			base:  chunkBase(ci) + alignDown(uintptr(j), 64)*pageSize,
+			cache: ^chunk.pages64(j),
+			scav:  chunk.scavenged.block64(j),
+		}
+	} else {
+		// Slow path: the searchAddr address had nothing there, so go find
+		// the first free page the slow way.
+		addr, _ := p.find(1)
+		if addr == 0 {
+			// We failed to find adequate free space, so mark the searchAddr as OoM
+			// and return an empty pageCache.
+			p.searchAddr = maxSearchAddr()
+			return pageCache{}
+		}
+		ci := chunkIndex(addr)
+		chunk = p.chunkOf(ci)
+		c = pageCache{
+			base:  alignDown(addr, 64*pageSize),
+			cache: ^chunk.pages64(chunkPageIndex(addr)),
+			scav:  chunk.scavenged.block64(chunkPageIndex(addr)),
+		}
+	}
+
+	// Set the page bits as allocated and clear the scavenged bits, but
+	// be careful to only set and clear the relevant bits.
+	cpi := chunkPageIndex(c.base)
+	chunk.allocPages64(cpi, c.cache)
+	chunk.scavenged.clearBlock64(cpi, c.cache&c.scav /* free and scavenged */)
+
+	// Update as an allocation, but note that it's not contiguous.
+	p.update(c.base, pageCachePages, false, true)
+
+	// Set the search address to the last page represented by the cache.
+	// Since all of the pages in this block are going to the cache, and we
+	// searched for the first free page, we can confidently start at the
+	// next page.
+	//
+	// However, p.searchAddr is not allowed to point into unmapped heap memory
+	// unless it is maxSearchAddr, so make it the last page as opposed to
+	// the page after.
+	p.searchAddr = offAddr{c.base + pageSize*(pageCachePages-1)}
+	return c
+}
diff --git a/contrib/go/_std_1.18/src/runtime/mpallocbits.go b/contrib/go/_std_1.19/src/runtime/mpallocbits.go
index f63164becd..f63164becd 100644
--- a/contrib/go/_std_1.18/src/runtime/mpallocbits.go
+++ b/contrib/go/_std_1.19/src/runtime/mpallocbits.go
diff --git a/contrib/go/_std_1.19/src/runtime/mprof.go b/contrib/go/_std_1.19/src/runtime/mprof.go
new file mode 100644
index 0000000000..99a67b9a3a
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/mprof.go
@@ -0,0 +1,1283 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Malloc profiling.
+// Patterned after tcmalloc's algorithms; shorter code.
+
+package runtime
+
+import (
+	"internal/abi"
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+// NOTE(rsc): Everything here could use cas if contention became an issue.
+var (
+	// profInsertLock protects changes to the start of all *bucket linked lists
+	profInsertLock mutex
+	// profBlockLock protects the contents of every blockRecord struct
+	profBlockLock mutex
+	// profMemActiveLock protects the active field of every memRecord struct
+	profMemActiveLock mutex
+	// profMemFutureLock is a set of locks that protect the respective elements
+	// of the future array of every memRecord struct
+	profMemFutureLock [len(memRecord{}.future)]mutex
+)
+
+// All memory allocations are local and do not escape outside of the profiler.
+// The profiler is forbidden from referring to garbage-collected memory.
+
+const (
+	// profile types
+	memProfile bucketType = 1 + iota
+	blockProfile
+	mutexProfile
+
+	// size of bucket hash table
+	buckHashSize = 179999
+
+	// max depth of stack to record in bucket
+	maxStack = 32
+)
+
+type bucketType int
+
+// A bucket holds per-call-stack profiling information.
+// The representation is a bit sleazy, inherited from C.
+// This struct defines the bucket header. It is followed in
+// memory by the stack words and then the actual record
+// data, either a memRecord or a blockRecord.
+//
+// Per-call-stack profiling information.
+// Lookup by hashing call stack into a linked-list hash table.
+//
+// None of the fields in this bucket header are modified after
+// creation, including its next and allnext links.
+//
+// No heap pointers.
+//
+//go:notinheap
+type bucket struct {
+	next    *bucket
+	allnext *bucket
+	typ     bucketType // memBucket or blockBucket (includes mutexProfile)
+	hash    uintptr
+	size    uintptr
+	nstk    uintptr
+}
+
+// A memRecord is the bucket data for a bucket of type memProfile,
+// part of the memory profile.
+type memRecord struct {
+	// The following complex 3-stage scheme of stats accumulation
+	// is required to obtain a consistent picture of mallocs and frees
+	// for some point in time.
+	// The problem is that mallocs come in real time, while frees
+	// come only after a GC during concurrent sweeping. So if we would
+	// naively count them, we would get a skew toward mallocs.
+	//
+	// Hence, we delay information to get consistent snapshots as
+	// of mark termination. Allocations count toward the next mark
+	// termination's snapshot, while sweep frees count toward the
+	// previous mark termination's snapshot:
+	//
+	//              MT          MT          MT          MT
+	//             .·|         .·|         .·|         .·|
+	//          .·˙  |      .·˙  |      .·˙  |      .·˙  |
+	//       .·˙     |   .·˙     |   .·˙     |   .·˙     |
+	//    .·˙        |.·˙        |.·˙        |.·˙        |
+	//
+	//       alloc → ▲ ← free
+	//               ┠┅┅┅┅┅┅┅┅┅┅┅P
+	//       C+2     →    C+1    →  C
+	//
+	//                   alloc → ▲ ← free
+	//                           ┠┅┅┅┅┅┅┅┅┅┅┅P
+	//                   C+2     →    C+1    →  C
+	//
+	// Since we can't publish a consistent snapshot until all of
+	// the sweep frees are accounted for, we wait until the next
+	// mark termination ("MT" above) to publish the previous mark
+	// termination's snapshot ("P" above). To do this, allocation
+	// and free events are accounted to *future* heap profile
+	// cycles ("C+n" above) and we only publish a cycle once all
+	// of the events from that cycle must be done. Specifically:
+	//
+	// Mallocs are accounted to cycle C+2.
+	// Explicit frees are accounted to cycle C+2.
+	// GC frees (done during sweeping) are accounted to cycle C+1.
+	//
+	// After mark termination, we increment the global heap
+	// profile cycle counter and accumulate the stats from cycle C
+	// into the active profile.
+
+	// active is the currently published profile. A profiling
+	// cycle can be accumulated into active once its complete.
+	active memRecordCycle
+
+	// future records the profile events we're counting for cycles
+	// that have not yet been published. This is ring buffer
+	// indexed by the global heap profile cycle C and stores
+	// cycles C, C+1, and C+2. Unlike active, these counts are
+	// only for a single cycle; they are not cumulative across
+	// cycles.
+	//
+	// We store cycle C here because there's a window between when
+	// C becomes the active cycle and when we've flushed it to
+	// active.
+	future [3]memRecordCycle
+}
+
+// memRecordCycle
+type memRecordCycle struct {
+	allocs, frees           uintptr
+	alloc_bytes, free_bytes uintptr
+}
+
+// add accumulates b into a. It does not zero b.
+func (a *memRecordCycle) add(b *memRecordCycle) {
+	a.allocs += b.allocs
+	a.frees += b.frees
+	a.alloc_bytes += b.alloc_bytes
+	a.free_bytes += b.free_bytes
+}
+
+// A blockRecord is the bucket data for a bucket of type blockProfile,
+// which is used in blocking and mutex profiles.
+type blockRecord struct {
+	count  float64
+	cycles int64
+}
+
+var (
+	mbuckets atomic.UnsafePointer // *bucket, memory profile buckets
+	bbuckets atomic.UnsafePointer // *bucket, blocking profile buckets
+	xbuckets atomic.UnsafePointer // *bucket, mutex profile buckets
+	buckhash atomic.UnsafePointer // *buckhashArray
+
+	mProfCycle mProfCycleHolder
+)
+
+type buckhashArray [buckHashSize]atomic.UnsafePointer // *bucket
+
+const mProfCycleWrap = uint32(len(memRecord{}.future)) * (2 << 24)
+
+// mProfCycleHolder holds the global heap profile cycle number (wrapped at
+// mProfCycleWrap, stored starting at bit 1), and a flag (stored at bit 0) to
+// indicate whether future[cycle] in all buckets has been queued to flush into
+// the active profile.
+type mProfCycleHolder struct {
+	value atomic.Uint32
+}
+
+// read returns the current cycle count.
+func (c *mProfCycleHolder) read() (cycle uint32) {
+	v := c.value.Load()
+	cycle = v >> 1
+	return cycle
+}
+
+// setFlushed sets the flushed flag. It returns the current cycle count and the
+// previous value of the flushed flag.
+func (c *mProfCycleHolder) setFlushed() (cycle uint32, alreadyFlushed bool) {
+	for {
+		prev := c.value.Load()
+		cycle = prev >> 1
+		alreadyFlushed = (prev & 0x1) != 0
+		next := prev | 0x1
+		if c.value.CompareAndSwap(prev, next) {
+			return cycle, alreadyFlushed
+		}
+	}
+}
+
+// increment increases the cycle count by one, wrapping the value at
+// mProfCycleWrap. It clears the flushed flag.
+func (c *mProfCycleHolder) increment() {
+	// We explicitly wrap mProfCycle rather than depending on
+	// uint wraparound because the memRecord.future ring does not
+	// itself wrap at a power of two.
+	for {
+		prev := c.value.Load()
+		cycle := prev >> 1
+		cycle = (cycle + 1) % mProfCycleWrap
+		next := cycle << 1
+		if c.value.CompareAndSwap(prev, next) {
+			break
+		}
+	}
+}
+
+// newBucket allocates a bucket with the given type and number of stack entries.
+func newBucket(typ bucketType, nstk int) *bucket {
+	size := unsafe.Sizeof(bucket{}) + uintptr(nstk)*unsafe.Sizeof(uintptr(0))
+	switch typ {
+	default:
+		throw("invalid profile bucket type")
+	case memProfile:
+		size += unsafe.Sizeof(memRecord{})
+	case blockProfile, mutexProfile:
+		size += unsafe.Sizeof(blockRecord{})
+	}
+
+	b := (*bucket)(persistentalloc(size, 0, &memstats.buckhash_sys))
+	b.typ = typ
+	b.nstk = uintptr(nstk)
+	return b
+}
+
+// stk returns the slice in b holding the stack.
+func (b *bucket) stk() []uintptr {
+	stk := (*[maxStack]uintptr)(add(unsafe.Pointer(b), unsafe.Sizeof(*b)))
+	return stk[:b.nstk:b.nstk]
+}
+
+// mp returns the memRecord associated with the memProfile bucket b.
+func (b *bucket) mp() *memRecord {
+	if b.typ != memProfile {
+		throw("bad use of bucket.mp")
+	}
+	data := add(unsafe.Pointer(b), unsafe.Sizeof(*b)+b.nstk*unsafe.Sizeof(uintptr(0)))
+	return (*memRecord)(data)
+}
+
+// bp returns the blockRecord associated with the blockProfile bucket b.
+func (b *bucket) bp() *blockRecord {
+	if b.typ != blockProfile && b.typ != mutexProfile {
+		throw("bad use of bucket.bp")
+	}
+	data := add(unsafe.Pointer(b), unsafe.Sizeof(*b)+b.nstk*unsafe.Sizeof(uintptr(0)))
+	return (*blockRecord)(data)
+}
+
+// Return the bucket for stk[0:nstk], allocating new bucket if needed.
+func stkbucket(typ bucketType, size uintptr, stk []uintptr, alloc bool) *bucket {
+	bh := (*buckhashArray)(buckhash.Load())
+	if bh == nil {
+		lock(&profInsertLock)
+		// check again under the lock
+		bh = (*buckhashArray)(buckhash.Load())
+		if bh == nil {
+			bh = (*buckhashArray)(sysAlloc(unsafe.Sizeof(buckhashArray{}), &memstats.buckhash_sys))
+			if bh == nil {
+				throw("runtime: cannot allocate memory")
+			}
+			buckhash.StoreNoWB(unsafe.Pointer(bh))
+		}
+		unlock(&profInsertLock)
+	}
+
+	// Hash stack.
+	var h uintptr
+	for _, pc := range stk {
+		h += pc
+		h += h << 10
+		h ^= h >> 6
+	}
+	// hash in size
+	h += size
+	h += h << 10
+	h ^= h >> 6
+	// finalize
+	h += h << 3
+	h ^= h >> 11
+
+	i := int(h % buckHashSize)
+	// first check optimistically, without the lock
+	for b := (*bucket)(bh[i].Load()); b != nil; b = b.next {
+		if b.typ == typ && b.hash == h && b.size == size && eqslice(b.stk(), stk) {
+			return b
+		}
+	}
+
+	if !alloc {
+		return nil
+	}
+
+	lock(&profInsertLock)
+	// check again under the insertion lock
+	for b := (*bucket)(bh[i].Load()); b != nil; b = b.next {
+		if b.typ == typ && b.hash == h && b.size == size && eqslice(b.stk(), stk) {
+			unlock(&profInsertLock)
+			return b
+		}
+	}
+
+	// Create new bucket.
+	b := newBucket(typ, len(stk))
+	copy(b.stk(), stk)
+	b.hash = h
+	b.size = size
+
+	var allnext *atomic.UnsafePointer
+	if typ == memProfile {
+		allnext = &mbuckets
+	} else if typ == mutexProfile {
+		allnext = &xbuckets
+	} else {
+		allnext = &bbuckets
+	}
+
+	b.next = (*bucket)(bh[i].Load())
+	b.allnext = (*bucket)(allnext.Load())
+
+	bh[i].StoreNoWB(unsafe.Pointer(b))
+	allnext.StoreNoWB(unsafe.Pointer(b))
+
+	unlock(&profInsertLock)
+	return b
+}
+
+func eqslice(x, y []uintptr) bool {
+	if len(x) != len(y) {
+		return false
+	}
+	for i, xi := range x {
+		if xi != y[i] {
+			return false
+		}
+	}
+	return true
+}
+
+// mProf_NextCycle publishes the next heap profile cycle and creates a
+// fresh heap profile cycle. This operation is fast and can be done
+// during STW. The caller must call mProf_Flush before calling
+// mProf_NextCycle again.
+//
+// This is called by mark termination during STW so allocations and
+// frees after the world is started again count towards a new heap
+// profiling cycle.
+func mProf_NextCycle() {
+	mProfCycle.increment()
+}
+
+// mProf_Flush flushes the events from the current heap profiling
+// cycle into the active profile. After this it is safe to start a new
+// heap profiling cycle with mProf_NextCycle.
+//
+// This is called by GC after mark termination starts the world. In
+// contrast with mProf_NextCycle, this is somewhat expensive, but safe
+// to do concurrently.
+func mProf_Flush() {
+	cycle, alreadyFlushed := mProfCycle.setFlushed()
+	if alreadyFlushed {
+		return
+	}
+
+	index := cycle % uint32(len(memRecord{}.future))
+	lock(&profMemActiveLock)
+	lock(&profMemFutureLock[index])
+	mProf_FlushLocked(index)
+	unlock(&profMemFutureLock[index])
+	unlock(&profMemActiveLock)
+}
+
+// mProf_FlushLocked flushes the events from the heap profiling cycle at index
+// into the active profile. The caller must hold the lock for the active profile
+// (profMemActiveLock) and for the profiling cycle at index
+// (profMemFutureLock[index]).
+func mProf_FlushLocked(index uint32) {
+	assertLockHeld(&profMemActiveLock)
+	assertLockHeld(&profMemFutureLock[index])
+	head := (*bucket)(mbuckets.Load())
+	for b := head; b != nil; b = b.allnext {
+		mp := b.mp()
+
+		// Flush cycle C into the published profile and clear
+		// it for reuse.
+		mpc := &mp.future[index]
+		mp.active.add(mpc)
+		*mpc = memRecordCycle{}
+	}
+}
+
+// mProf_PostSweep records that all sweep frees for this GC cycle have
+// completed. This has the effect of publishing the heap profile
+// snapshot as of the last mark termination without advancing the heap
+// profile cycle.
+func mProf_PostSweep() {
+	// Flush cycle C+1 to the active profile so everything as of
+	// the last mark termination becomes visible. *Don't* advance
+	// the cycle, since we're still accumulating allocs in cycle
+	// C+2, which have to become C+1 in the next mark termination
+	// and so on.
+	cycle := mProfCycle.read() + 1
+
+	index := cycle % uint32(len(memRecord{}.future))
+	lock(&profMemActiveLock)
+	lock(&profMemFutureLock[index])
+	mProf_FlushLocked(index)
+	unlock(&profMemFutureLock[index])
+	unlock(&profMemActiveLock)
+}
+
+// Called by malloc to record a profiled block.
+func mProf_Malloc(p unsafe.Pointer, size uintptr) {
+	var stk [maxStack]uintptr
+	nstk := callers(4, stk[:])
+
+	index := (mProfCycle.read() + 2) % uint32(len(memRecord{}.future))
+
+	b := stkbucket(memProfile, size, stk[:nstk], true)
+	mp := b.mp()
+	mpc := &mp.future[index]
+
+	lock(&profMemFutureLock[index])
+	mpc.allocs++
+	mpc.alloc_bytes += size
+	unlock(&profMemFutureLock[index])
+
+	// Setprofilebucket locks a bunch of other mutexes, so we call it outside of
+	// the profiler locks. This reduces potential contention and chances of
+	// deadlocks. Since the object must be alive during the call to
+	// mProf_Malloc, it's fine to do this non-atomically.
+	systemstack(func() {
+		setprofilebucket(p, b)
+	})
+}
+
+// Called when freeing a profiled block.
+func mProf_Free(b *bucket, size uintptr) {
+	index := (mProfCycle.read() + 1) % uint32(len(memRecord{}.future))
+
+	mp := b.mp()
+	mpc := &mp.future[index]
+
+	lock(&profMemFutureLock[index])
+	mpc.frees++
+	mpc.free_bytes += size
+	unlock(&profMemFutureLock[index])
+}
+
+var blockprofilerate uint64 // in CPU ticks
+
+// SetBlockProfileRate controls the fraction of goroutine blocking events
+// that are reported in the blocking profile. The profiler aims to sample
+// an average of one blocking event per rate nanoseconds spent blocked.
+//
+// To include every blocking event in the profile, pass rate = 1.
+// To turn off profiling entirely, pass rate <= 0.
+func SetBlockProfileRate(rate int) {
+	var r int64
+	if rate <= 0 {
+		r = 0 // disable profiling
+	} else if rate == 1 {
+		r = 1 // profile everything
+	} else {
+		// convert ns to cycles, use float64 to prevent overflow during multiplication
+		r = int64(float64(rate) * float64(tickspersecond()) / (1000 * 1000 * 1000))
+		if r == 0 {
+			r = 1
+		}
+	}
+
+	atomic.Store64(&blockprofilerate, uint64(r))
+}
+
+func blockevent(cycles int64, skip int) {
+	if cycles <= 0 {
+		cycles = 1
+	}
+
+	rate := int64(atomic.Load64(&blockprofilerate))
+	if blocksampled(cycles, rate) {
+		saveblockevent(cycles, rate, skip+1, blockProfile)
+	}
+}
+
+// blocksampled returns true for all events where cycles >= rate. Shorter
+// events have a cycles/rate random chance of returning true.
+func blocksampled(cycles, rate int64) bool {
+	if rate <= 0 || (rate > cycles && int64(fastrand())%rate > cycles) {
+		return false
+	}
+	return true
+}
+
+func saveblockevent(cycles, rate int64, skip int, which bucketType) {
+	gp := getg()
+	var nstk int
+	var stk [maxStack]uintptr
+	if gp.m.curg == nil || gp.m.curg == gp {
+		nstk = callers(skip, stk[:])
+	} else {
+		nstk = gcallers(gp.m.curg, skip, stk[:])
+	}
+	b := stkbucket(which, 0, stk[:nstk], true)
+	bp := b.bp()
+
+	lock(&profBlockLock)
+	if which == blockProfile && cycles < rate {
+		// Remove sampling bias, see discussion on http://golang.org/cl/299991.
+		bp.count += float64(rate) / float64(cycles)
+		bp.cycles += rate
+	} else {
+		bp.count++
+		bp.cycles += cycles
+	}
+	unlock(&profBlockLock)
+}
+
+var mutexprofilerate uint64 // fraction sampled
+
+// SetMutexProfileFraction controls the fraction of mutex contention events
+// that are reported in the mutex profile. On average 1/rate events are
+// reported. The previous rate is returned.
+//
+// To turn off profiling entirely, pass rate 0.
+// To just read the current rate, pass rate < 0.
+// (For n>1 the details of sampling may change.)
+func SetMutexProfileFraction(rate int) int {
+	if rate < 0 {
+		return int(mutexprofilerate)
+	}
+	old := mutexprofilerate
+	atomic.Store64(&mutexprofilerate, uint64(rate))
+	return int(old)
+}
+
+//go:linkname mutexevent sync.event
+func mutexevent(cycles int64, skip int) {
+	if cycles < 0 {
+		cycles = 0
+	}
+	rate := int64(atomic.Load64(&mutexprofilerate))
+	// TODO(pjw): measure impact of always calling fastrand vs using something
+	// like malloc.go:nextSample()
+	if rate > 0 && int64(fastrand())%rate == 0 {
+		saveblockevent(cycles, rate, skip+1, mutexProfile)
+	}
+}
+
+// Go interface to profile data.
+
+// A StackRecord describes a single execution stack.
+type StackRecord struct {
+	Stack0 [32]uintptr // stack trace for this record; ends at first 0 entry
+}
+
+// Stack returns the stack trace associated with the record,
+// a prefix of r.Stack0.
+func (r *StackRecord) Stack() []uintptr {
+	for i, v := range r.Stack0 {
+		if v == 0 {
+			return r.Stack0[0:i]
+		}
+	}
+	return r.Stack0[0:]
+}
+
+// MemProfileRate controls the fraction of memory allocations
+// that are recorded and reported in the memory profile.
+// The profiler aims to sample an average of
+// one allocation per MemProfileRate bytes allocated.
+//
+// To include every allocated block in the profile, set MemProfileRate to 1.
+// To turn off profiling entirely, set MemProfileRate to 0.
+//
+// The tools that process the memory profiles assume that the
+// profile rate is constant across the lifetime of the program
+// and equal to the current value. Programs that change the
+// memory profiling rate should do so just once, as early as
+// possible in the execution of the program (for example,
+// at the beginning of main).
+var MemProfileRate int = defaultMemProfileRate(512 * 1024)
+
+// defaultMemProfileRate returns 0 if disableMemoryProfiling is set.
+// It exists primarily for the godoc rendering of MemProfileRate
+// above.
+func defaultMemProfileRate(v int) int {
+	if disableMemoryProfiling {
+		return 0
+	}
+	return v
+}
+
+// disableMemoryProfiling is set by the linker if runtime.MemProfile
+// is not used and the link type guarantees nobody else could use it
+// elsewhere.
+var disableMemoryProfiling bool
+
+// A MemProfileRecord describes the live objects allocated
+// by a particular call sequence (stack trace).
+type MemProfileRecord struct {
+	AllocBytes, FreeBytes     int64       // number of bytes allocated, freed
+	AllocObjects, FreeObjects int64       // number of objects allocated, freed
+	Stack0                    [32]uintptr // stack trace for this record; ends at first 0 entry
+}
+
+// InUseBytes returns the number of bytes in use (AllocBytes - FreeBytes).
+func (r *MemProfileRecord) InUseBytes() int64 { return r.AllocBytes - r.FreeBytes }
+
+// InUseObjects returns the number of objects in use (AllocObjects - FreeObjects).
+func (r *MemProfileRecord) InUseObjects() int64 {
+	return r.AllocObjects - r.FreeObjects
+}
+
+// Stack returns the stack trace associated with the record,
+// a prefix of r.Stack0.
+func (r *MemProfileRecord) Stack() []uintptr {
+	for i, v := range r.Stack0 {
+		if v == 0 {
+			return r.Stack0[0:i]
+		}
+	}
+	return r.Stack0[0:]
+}
+
+// MemProfile returns a profile of memory allocated and freed per allocation
+// site.
+//
+// MemProfile returns n, the number of records in the current memory profile.
+// If len(p) >= n, MemProfile copies the profile into p and returns n, true.
+// If len(p) < n, MemProfile does not change p and returns n, false.
+//
+// If inuseZero is true, the profile includes allocation records
+// where r.AllocBytes > 0 but r.AllocBytes == r.FreeBytes.
+// These are sites where memory was allocated, but it has all
+// been released back to the runtime.
+//
+// The returned profile may be up to two garbage collection cycles old.
+// This is to avoid skewing the profile toward allocations; because
+// allocations happen in real time but frees are delayed until the garbage
+// collector performs sweeping, the profile only accounts for allocations
+// that have had a chance to be freed by the garbage collector.
+//
+// Most clients should use the runtime/pprof package or
+// the testing package's -test.memprofile flag instead
+// of calling MemProfile directly.
+func MemProfile(p []MemProfileRecord, inuseZero bool) (n int, ok bool) {
+	cycle := mProfCycle.read()
+	// If we're between mProf_NextCycle and mProf_Flush, take care
+	// of flushing to the active profile so we only have to look
+	// at the active profile below.
+	index := cycle % uint32(len(memRecord{}.future))
+	lock(&profMemActiveLock)
+	lock(&profMemFutureLock[index])
+	mProf_FlushLocked(index)
+	unlock(&profMemFutureLock[index])
+	clear := true
+	head := (*bucket)(mbuckets.Load())
+	for b := head; b != nil; b = b.allnext {
+		mp := b.mp()
+		if inuseZero || mp.active.alloc_bytes != mp.active.free_bytes {
+			n++
+		}
+		if mp.active.allocs != 0 || mp.active.frees != 0 {
+			clear = false
+		}
+	}
+	if clear {
+		// Absolutely no data, suggesting that a garbage collection
+		// has not yet happened. In order to allow profiling when
+		// garbage collection is disabled from the beginning of execution,
+		// accumulate all of the cycles, and recount buckets.
+		n = 0
+		for b := head; b != nil; b = b.allnext {
+			mp := b.mp()
+			for c := range mp.future {
+				lock(&profMemFutureLock[c])
+				mp.active.add(&mp.future[c])
+				mp.future[c] = memRecordCycle{}
+				unlock(&profMemFutureLock[c])
+			}
+			if inuseZero || mp.active.alloc_bytes != mp.active.free_bytes {
+				n++
+			}
+		}
+	}
+	if n <= len(p) {
+		ok = true
+		idx := 0
+		for b := head; b != nil; b = b.allnext {
+			mp := b.mp()
+			if inuseZero || mp.active.alloc_bytes != mp.active.free_bytes {
+				record(&p[idx], b)
+				idx++
+			}
+		}
+	}
+	unlock(&profMemActiveLock)
+	return
+}
+
+// Write b's data to r.
+func record(r *MemProfileRecord, b *bucket) {
+	mp := b.mp()
+	r.AllocBytes = int64(mp.active.alloc_bytes)
+	r.FreeBytes = int64(mp.active.free_bytes)
+	r.AllocObjects = int64(mp.active.allocs)
+	r.FreeObjects = int64(mp.active.frees)
+	if raceenabled {
+		racewriterangepc(unsafe.Pointer(&r.Stack0[0]), unsafe.Sizeof(r.Stack0), getcallerpc(), abi.FuncPCABIInternal(MemProfile))
+	}
+	if msanenabled {
+		msanwrite(unsafe.Pointer(&r.Stack0[0]), unsafe.Sizeof(r.Stack0))
+	}
+	if asanenabled {
+		asanwrite(unsafe.Pointer(&r.Stack0[0]), unsafe.Sizeof(r.Stack0))
+	}
+	copy(r.Stack0[:], b.stk())
+	for i := int(b.nstk); i < len(r.Stack0); i++ {
+		r.Stack0[i] = 0
+	}
+}
+
+func iterate_memprof(fn func(*bucket, uintptr, *uintptr, uintptr, uintptr, uintptr)) {
+	lock(&profMemActiveLock)
+	head := (*bucket)(mbuckets.Load())
+	for b := head; b != nil; b = b.allnext {
+		mp := b.mp()
+		fn(b, b.nstk, &b.stk()[0], b.size, mp.active.allocs, mp.active.frees)
+	}
+	unlock(&profMemActiveLock)
+}
+
+// BlockProfileRecord describes blocking events originated
+// at a particular call sequence (stack trace).
+type BlockProfileRecord struct {
+	Count  int64
+	Cycles int64
+	StackRecord
+}
+
+// BlockProfile returns n, the number of records in the current blocking profile.
+// If len(p) >= n, BlockProfile copies the profile into p and returns n, true.
+// If len(p) < n, BlockProfile does not change p and returns n, false.
+//
+// Most clients should use the runtime/pprof package or
+// the testing package's -test.blockprofile flag instead
+// of calling BlockProfile directly.
+func BlockProfile(p []BlockProfileRecord) (n int, ok bool) {
+	lock(&profBlockLock)
+	head := (*bucket)(bbuckets.Load())
+	for b := head; b != nil; b = b.allnext {
+		n++
+	}
+	if n <= len(p) {
+		ok = true
+		for b := head; b != nil; b = b.allnext {
+			bp := b.bp()
+			r := &p[0]
+			r.Count = int64(bp.count)
+			// Prevent callers from having to worry about division by zero errors.
+			// See discussion on http://golang.org/cl/299991.
+			if r.Count == 0 {
+				r.Count = 1
+			}
+			r.Cycles = bp.cycles
+			if raceenabled {
+				racewriterangepc(unsafe.Pointer(&r.Stack0[0]), unsafe.Sizeof(r.Stack0), getcallerpc(), abi.FuncPCABIInternal(BlockProfile))
+			}
+			if msanenabled {
+				msanwrite(unsafe.Pointer(&r.Stack0[0]), unsafe.Sizeof(r.Stack0))
+			}
+			if asanenabled {
+				asanwrite(unsafe.Pointer(&r.Stack0[0]), unsafe.Sizeof(r.Stack0))
+			}
+			i := copy(r.Stack0[:], b.stk())
+			for ; i < len(r.Stack0); i++ {
+				r.Stack0[i] = 0
+			}
+			p = p[1:]
+		}
+	}
+	unlock(&profBlockLock)
+	return
+}
+
+// MutexProfile returns n, the number of records in the current mutex profile.
+// If len(p) >= n, MutexProfile copies the profile into p and returns n, true.
+// Otherwise, MutexProfile does not change p, and returns n, false.
+//
+// Most clients should use the runtime/pprof package
+// instead of calling MutexProfile directly.
+func MutexProfile(p []BlockProfileRecord) (n int, ok bool) {
+	lock(&profBlockLock)
+	head := (*bucket)(xbuckets.Load())
+	for b := head; b != nil; b = b.allnext {
+		n++
+	}
+	if n <= len(p) {
+		ok = true
+		for b := head; b != nil; b = b.allnext {
+			bp := b.bp()
+			r := &p[0]
+			r.Count = int64(bp.count)
+			r.Cycles = bp.cycles
+			i := copy(r.Stack0[:], b.stk())
+			for ; i < len(r.Stack0); i++ {
+				r.Stack0[i] = 0
+			}
+			p = p[1:]
+		}
+	}
+	unlock(&profBlockLock)
+	return
+}
+
+// ThreadCreateProfile returns n, the number of records in the thread creation profile.
+// If len(p) >= n, ThreadCreateProfile copies the profile into p and returns n, true.
+// If len(p) < n, ThreadCreateProfile does not change p and returns n, false.
+//
+// Most clients should use the runtime/pprof package instead
+// of calling ThreadCreateProfile directly.
+func ThreadCreateProfile(p []StackRecord) (n int, ok bool) {
+	first := (*m)(atomic.Loadp(unsafe.Pointer(&allm)))
+	for mp := first; mp != nil; mp = mp.alllink {
+		n++
+	}
+	if n <= len(p) {
+		ok = true
+		i := 0
+		for mp := first; mp != nil; mp = mp.alllink {
+			p[i].Stack0 = mp.createstack
+			i++
+		}
+	}
+	return
+}
+
+//go:linkname runtime_goroutineProfileWithLabels runtime/pprof.runtime_goroutineProfileWithLabels
+func runtime_goroutineProfileWithLabels(p []StackRecord, labels []unsafe.Pointer) (n int, ok bool) {
+	return goroutineProfileWithLabels(p, labels)
+}
+
+const go119ConcurrentGoroutineProfile = true
+
+// labels may be nil. If labels is non-nil, it must have the same length as p.
+func goroutineProfileWithLabels(p []StackRecord, labels []unsafe.Pointer) (n int, ok bool) {
+	if labels != nil && len(labels) != len(p) {
+		labels = nil
+	}
+
+	if go119ConcurrentGoroutineProfile {
+		return goroutineProfileWithLabelsConcurrent(p, labels)
+	}
+	return goroutineProfileWithLabelsSync(p, labels)
+}
+
+var goroutineProfile = struct {
+	sema    uint32
+	active  bool
+	offset  atomic.Int64
+	records []StackRecord
+	labels  []unsafe.Pointer
+}{
+	sema: 1,
+}
+
+// goroutineProfileState indicates the status of a goroutine's stack for the
+// current in-progress goroutine profile. Goroutines' stacks are initially
+// "Absent" from the profile, and end up "Satisfied" by the time the profile is
+// complete. While a goroutine's stack is being captured, its
+// goroutineProfileState will be "InProgress" and it will not be able to run
+// until the capture completes and the state moves to "Satisfied".
+//
+// Some goroutines (the finalizer goroutine, which at various times can be
+// either a "system" or a "user" goroutine, and the goroutine that is
+// coordinating the profile, any goroutines created during the profile) move
+// directly to the "Satisfied" state.
+type goroutineProfileState uint32
+
+const (
+	goroutineProfileAbsent goroutineProfileState = iota
+	goroutineProfileInProgress
+	goroutineProfileSatisfied
+)
+
+type goroutineProfileStateHolder atomic.Uint32
+
+func (p *goroutineProfileStateHolder) Load() goroutineProfileState {
+	return goroutineProfileState((*atomic.Uint32)(p).Load())
+}
+
+func (p *goroutineProfileStateHolder) Store(value goroutineProfileState) {
+	(*atomic.Uint32)(p).Store(uint32(value))
+}
+
+func (p *goroutineProfileStateHolder) CompareAndSwap(old, new goroutineProfileState) bool {
+	return (*atomic.Uint32)(p).CompareAndSwap(uint32(old), uint32(new))
+}
+
+func goroutineProfileWithLabelsConcurrent(p []StackRecord, labels []unsafe.Pointer) (n int, ok bool) {
+	semacquire(&goroutineProfile.sema)
+
+	ourg := getg()
+
+	stopTheWorld("profile")
+	// Using gcount while the world is stopped should give us a consistent view
+	// of the number of live goroutines, minus the number of goroutines that are
+	// alive and permanently marked as "system". But to make this count agree
+	// with what we'd get from isSystemGoroutine, we need special handling for
+	// goroutines that can vary between user and system to ensure that the count
+	// doesn't change during the collection. So, check the finalizer goroutine
+	// in particular.
+	n = int(gcount())
+	if fingRunning {
+		n++
+	}
+
+	if n > len(p) {
+		// There's not enough space in p to store the whole profile, so (per the
+		// contract of runtime.GoroutineProfile) we're not allowed to write to p
+		// at all and must return n, false.
+		startTheWorld()
+		semrelease(&goroutineProfile.sema)
+		return n, false
+	}
+
+	// Save current goroutine.
+	sp := getcallersp()
+	pc := getcallerpc()
+	systemstack(func() {
+		saveg(pc, sp, ourg, &p[0])
+	})
+	ourg.goroutineProfiled.Store(goroutineProfileSatisfied)
+	goroutineProfile.offset.Store(1)
+
+	// Prepare for all other goroutines to enter the profile. Aside from ourg,
+	// every goroutine struct in the allgs list has its goroutineProfiled field
+	// cleared. Any goroutine created from this point on (while
+	// goroutineProfile.active is set) will start with its goroutineProfiled
+	// field set to goroutineProfileSatisfied.
+	goroutineProfile.active = true
+	goroutineProfile.records = p
+	goroutineProfile.labels = labels
+	// The finalizer goroutine needs special handling because it can vary over
+	// time between being a user goroutine (eligible for this profile) and a
+	// system goroutine (to be excluded). Pick one before restarting the world.
+	if fing != nil {
+		fing.goroutineProfiled.Store(goroutineProfileSatisfied)
+		if readgstatus(fing) != _Gdead && !isSystemGoroutine(fing, false) {
+			doRecordGoroutineProfile(fing)
+		}
+	}
+	startTheWorld()
+
+	// Visit each goroutine that existed as of the startTheWorld call above.
+	//
+	// New goroutines may not be in this list, but we didn't want to know about
+	// them anyway. If they do appear in this list (via reusing a dead goroutine
+	// struct, or racing to launch between the world restarting and us getting
+	// the list), they will already have their goroutineProfiled field set to
+	// goroutineProfileSatisfied before their state transitions out of _Gdead.
+	//
+	// Any goroutine that the scheduler tries to execute concurrently with this
+	// call will start by adding itself to the profile (before the act of
+	// executing can cause any changes in its stack).
+	forEachGRace(func(gp1 *g) {
+		tryRecordGoroutineProfile(gp1, Gosched)
+	})
+
+	stopTheWorld("profile cleanup")
+	endOffset := goroutineProfile.offset.Swap(0)
+	goroutineProfile.active = false
+	goroutineProfile.records = nil
+	goroutineProfile.labels = nil
+	startTheWorld()
+
+	// Restore the invariant that every goroutine struct in allgs has its
+	// goroutineProfiled field cleared.
+	forEachGRace(func(gp1 *g) {
+		gp1.goroutineProfiled.Store(goroutineProfileAbsent)
+	})
+
+	if raceenabled {
+		raceacquire(unsafe.Pointer(&labelSync))
+	}
+
+	if n != int(endOffset) {
+		// It's a big surprise that the number of goroutines changed while we
+		// were collecting the profile. But probably better to return a
+		// truncated profile than to crash the whole process.
+		//
+		// For instance, needm moves a goroutine out of the _Gdead state and so
+		// might be able to change the goroutine count without interacting with
+		// the scheduler. For code like that, the race windows are small and the
+		// combination of features is uncommon, so it's hard to be (and remain)
+		// sure we've caught them all.
+	}
+
+	semrelease(&goroutineProfile.sema)
+	return n, true
+}
+
+// tryRecordGoroutineProfileWB asserts that write barriers are allowed and calls
+// tryRecordGoroutineProfile.
+//
+//go:yeswritebarrierrec
+func tryRecordGoroutineProfileWB(gp1 *g) {
+	if getg().m.p.ptr() == nil {
+		throw("no P available, write barriers are forbidden")
+	}
+	tryRecordGoroutineProfile(gp1, osyield)
+}
+
+// tryRecordGoroutineProfile ensures that gp1 has the appropriate representation
+// in the current goroutine profile: either that it should not be profiled, or
+// that a snapshot of its call stack and labels are now in the profile.
+func tryRecordGoroutineProfile(gp1 *g, yield func()) {
+	if readgstatus(gp1) == _Gdead {
+		// Dead goroutines should not appear in the profile. Goroutines that
+		// start while profile collection is active will get goroutineProfiled
+		// set to goroutineProfileSatisfied before transitioning out of _Gdead,
+		// so here we check _Gdead first.
+		return
+	}
+	if isSystemGoroutine(gp1, true) {
+		// System goroutines should not appear in the profile. (The finalizer
+		// goroutine is marked as "already profiled".)
+		return
+	}
+
+	for {
+		prev := gp1.goroutineProfiled.Load()
+		if prev == goroutineProfileSatisfied {
+			// This goroutine is already in the profile (or is new since the
+			// start of collection, so shouldn't appear in the profile).
+			break
+		}
+		if prev == goroutineProfileInProgress {
+			// Something else is adding gp1 to the goroutine profile right now.
+			// Give that a moment to finish.
+			yield()
+			continue
+		}
+
+		// While we have gp1.goroutineProfiled set to
+		// goroutineProfileInProgress, gp1 may appear _Grunnable but will not
+		// actually be able to run. Disable preemption for ourselves, to make
+		// sure we finish profiling gp1 right away instead of leaving it stuck
+		// in this limbo.
+		mp := acquirem()
+		if gp1.goroutineProfiled.CompareAndSwap(goroutineProfileAbsent, goroutineProfileInProgress) {
+			doRecordGoroutineProfile(gp1)
+			gp1.goroutineProfiled.Store(goroutineProfileSatisfied)
+		}
+		releasem(mp)
+	}
+}
+
+// doRecordGoroutineProfile writes gp1's call stack and labels to an in-progress
+// goroutine profile. Preemption is disabled.
+//
+// This may be called via tryRecordGoroutineProfile in two ways: by the
+// goroutine that is coordinating the goroutine profile (running on its own
+// stack), or from the scheduler in preparation to execute gp1 (running on the
+// system stack).
+func doRecordGoroutineProfile(gp1 *g) {
+	if readgstatus(gp1) == _Grunning {
+		print("doRecordGoroutineProfile gp1=", gp1.goid, "\n")
+		throw("cannot read stack of running goroutine")
+	}
+
+	offset := int(goroutineProfile.offset.Add(1)) - 1
+
+	if offset >= len(goroutineProfile.records) {
+		// Should be impossible, but better to return a truncated profile than
+		// to crash the entire process at this point. Instead, deal with it in
+		// goroutineProfileWithLabelsConcurrent where we have more context.
+		return
+	}
+
+	// saveg calls gentraceback, which may call cgo traceback functions. When
+	// called from the scheduler, this is on the system stack already so
+	// traceback.go:cgoContextPCs will avoid calling back into the scheduler.
+	//
+	// When called from the goroutine coordinating the profile, we still have
+	// set gp1.goroutineProfiled to goroutineProfileInProgress and so are still
+	// preventing it from being truly _Grunnable. So we'll use the system stack
+	// to avoid schedule delays.
+	systemstack(func() { saveg(^uintptr(0), ^uintptr(0), gp1, &goroutineProfile.records[offset]) })
+
+	if goroutineProfile.labels != nil {
+		goroutineProfile.labels[offset] = gp1.labels
+	}
+}
+
+func goroutineProfileWithLabelsSync(p []StackRecord, labels []unsafe.Pointer) (n int, ok bool) {
+	gp := getg()
+
+	isOK := func(gp1 *g) bool {
+		// Checking isSystemGoroutine here makes GoroutineProfile
+		// consistent with both NumGoroutine and Stack.
+		return gp1 != gp && readgstatus(gp1) != _Gdead && !isSystemGoroutine(gp1, false)
+	}
+
+	stopTheWorld("profile")
+
+	// World is stopped, no locking required.
+	n = 1
+	forEachGRace(func(gp1 *g) {
+		if isOK(gp1) {
+			n++
+		}
+	})
+
+	if n <= len(p) {
+		ok = true
+		r, lbl := p, labels
+
+		// Save current goroutine.
+		sp := getcallersp()
+		pc := getcallerpc()
+		systemstack(func() {
+			saveg(pc, sp, gp, &r[0])
+		})
+		r = r[1:]
+
+		// If we have a place to put our goroutine labelmap, insert it there.
+		if labels != nil {
+			lbl[0] = gp.labels
+			lbl = lbl[1:]
+		}
+
+		// Save other goroutines.
+		forEachGRace(func(gp1 *g) {
+			if !isOK(gp1) {
+				return
+			}
+
+			if len(r) == 0 {
+				// Should be impossible, but better to return a
+				// truncated profile than to crash the entire process.
+				return
+			}
+			// saveg calls gentraceback, which may call cgo traceback functions.
+			// The world is stopped, so it cannot use cgocall (which will be
+			// blocked at exitsyscall). Do it on the system stack so it won't
+			// call into the schedular (see traceback.go:cgoContextPCs).
+			systemstack(func() { saveg(^uintptr(0), ^uintptr(0), gp1, &r[0]) })
+			if labels != nil {
+				lbl[0] = gp1.labels
+				lbl = lbl[1:]
+			}
+			r = r[1:]
+		})
+	}
+
+	if raceenabled {
+		raceacquire(unsafe.Pointer(&labelSync))
+	}
+
+	startTheWorld()
+	return n, ok
+}
+
+// GoroutineProfile returns n, the number of records in the active goroutine stack profile.
+// If len(p) >= n, GoroutineProfile copies the profile into p and returns n, true.
+// If len(p) < n, GoroutineProfile does not change p and returns n, false.
+//
+// Most clients should use the runtime/pprof package instead
+// of calling GoroutineProfile directly.
+func GoroutineProfile(p []StackRecord) (n int, ok bool) {
+
+	return goroutineProfileWithLabels(p, nil)
+}
+
+func saveg(pc, sp uintptr, gp *g, r *StackRecord) {
+	n := gentraceback(pc, sp, 0, gp, 0, &r.Stack0[0], len(r.Stack0), nil, nil, 0)
+	if n < len(r.Stack0) {
+		r.Stack0[n] = 0
+	}
+}
+
+// Stack formats a stack trace of the calling goroutine into buf
+// and returns the number of bytes written to buf.
+// If all is true, Stack formats stack traces of all other goroutines
+// into buf after the trace for the current goroutine.
+func Stack(buf []byte, all bool) int {
+	if all {
+		stopTheWorld("stack trace")
+	}
+
+	n := 0
+	if len(buf) > 0 {
+		gp := getg()
+		sp := getcallersp()
+		pc := getcallerpc()
+		systemstack(func() {
+			g0 := getg()
+			// Force traceback=1 to override GOTRACEBACK setting,
+			// so that Stack's results are consistent.
+			// GOTRACEBACK is only about crash dumps.
+			g0.m.traceback = 1
+			g0.writebuf = buf[0:0:len(buf)]
+			goroutineheader(gp)
+			traceback(pc, sp, 0, gp)
+			if all {
+				tracebackothers(gp)
+			}
+			g0.m.traceback = 0
+			n = len(g0.writebuf)
+			g0.writebuf = nil
+		})
+	}
+
+	if all {
+		startTheWorld()
+	}
+	return n
+}
+
+// Tracing of alloc/free/gc.
+
+var tracelock mutex
+
+func tracealloc(p unsafe.Pointer, size uintptr, typ *_type) {
+	lock(&tracelock)
+	gp := getg()
+	gp.m.traceback = 2
+	if typ == nil {
+		print("tracealloc(", p, ", ", hex(size), ")\n")
+	} else {
+		print("tracealloc(", p, ", ", hex(size), ", ", typ.string(), ")\n")
+	}
+	if gp.m.curg == nil || gp == gp.m.curg {
+		goroutineheader(gp)
+		pc := getcallerpc()
+		sp := getcallersp()
+		systemstack(func() {
+			traceback(pc, sp, 0, gp)
+		})
+	} else {
+		goroutineheader(gp.m.curg)
+		traceback(^uintptr(0), ^uintptr(0), 0, gp.m.curg)
+	}
+	print("\n")
+	gp.m.traceback = 0
+	unlock(&tracelock)
+}
+
+func tracefree(p unsafe.Pointer, size uintptr) {
+	lock(&tracelock)
+	gp := getg()
+	gp.m.traceback = 2
+	print("tracefree(", p, ", ", hex(size), ")\n")
+	goroutineheader(gp)
+	pc := getcallerpc()
+	sp := getcallersp()
+	systemstack(func() {
+		traceback(pc, sp, 0, gp)
+	})
+	print("\n")
+	gp.m.traceback = 0
+	unlock(&tracelock)
+}
+
+func tracegc() {
+	lock(&tracelock)
+	gp := getg()
+	gp.m.traceback = 2
+	print("tracegc()\n")
+	// running on m->g0 stack; show all non-g0 goroutines
+	tracebackothers(gp)
+	print("end tracegc\n")
+	print("\n")
+	gp.m.traceback = 0
+	unlock(&tracelock)
+}
diff --git a/contrib/go/_std_1.19/src/runtime/mranges.go b/contrib/go/_std_1.19/src/runtime/mranges.go
new file mode 100644
index 0000000000..9cf83cc613
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/mranges.go
@@ -0,0 +1,436 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Address range data structure.
+//
+// This file contains an implementation of a data structure which
+// manages ordered address ranges.
+
+package runtime
+
+import (
+	"internal/goarch"
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+// addrRange represents a region of address space.
+//
+// An addrRange must never span a gap in the address space.
+type addrRange struct {
+	// base and limit together represent the region of address space
+	// [base, limit). That is, base is inclusive, limit is exclusive.
+	// These are address over an offset view of the address space on
+	// platforms with a segmented address space, that is, on platforms
+	// where arenaBaseOffset != 0.
+	base, limit offAddr
+}
+
+// makeAddrRange creates a new address range from two virtual addresses.
+//
+// Throws if the base and limit are not in the same memory segment.
+func makeAddrRange(base, limit uintptr) addrRange {
+	r := addrRange{offAddr{base}, offAddr{limit}}
+	if (base-arenaBaseOffset >= base) != (limit-arenaBaseOffset >= limit) {
+		throw("addr range base and limit are not in the same memory segment")
+	}
+	return r
+}
+
+// size returns the size of the range represented in bytes.
+func (a addrRange) size() uintptr {
+	if !a.base.lessThan(a.limit) {
+		return 0
+	}
+	// Subtraction is safe because limit and base must be in the same
+	// segment of the address space.
+	return a.limit.diff(a.base)
+}
+
+// contains returns whether or not the range contains a given address.
+func (a addrRange) contains(addr uintptr) bool {
+	return a.base.lessEqual(offAddr{addr}) && (offAddr{addr}).lessThan(a.limit)
+}
+
+// subtract takes the addrRange toPrune and cuts out any overlap with
+// from, then returns the new range. subtract assumes that a and b
+// either don't overlap at all, only overlap on one side, or are equal.
+// If b is strictly contained in a, thus forcing a split, it will throw.
+func (a addrRange) subtract(b addrRange) addrRange {
+	if b.base.lessEqual(a.base) && a.limit.lessEqual(b.limit) {
+		return addrRange{}
+	} else if a.base.lessThan(b.base) && b.limit.lessThan(a.limit) {
+		throw("bad prune")
+	} else if b.limit.lessThan(a.limit) && a.base.lessThan(b.limit) {
+		a.base = b.limit
+	} else if a.base.lessThan(b.base) && b.base.lessThan(a.limit) {
+		a.limit = b.base
+	}
+	return a
+}
+
+// removeGreaterEqual removes all addresses in a greater than or equal
+// to addr and returns the new range.
+func (a addrRange) removeGreaterEqual(addr uintptr) addrRange {
+	if (offAddr{addr}).lessEqual(a.base) {
+		return addrRange{}
+	}
+	if a.limit.lessEqual(offAddr{addr}) {
+		return a
+	}
+	return makeAddrRange(a.base.addr(), addr)
+}
+
+var (
+	// minOffAddr is the minimum address in the offset space, and
+	// it corresponds to the virtual address arenaBaseOffset.
+	minOffAddr = offAddr{arenaBaseOffset}
+
+	// maxOffAddr is the maximum address in the offset address
+	// space. It corresponds to the highest virtual address representable
+	// by the page alloc chunk and heap arena maps.
+	maxOffAddr = offAddr{(((1 << heapAddrBits) - 1) + arenaBaseOffset) & uintptrMask}
+)
+
+// offAddr represents an address in a contiguous view
+// of the address space on systems where the address space is
+// segmented. On other systems, it's just a normal address.
+type offAddr struct {
+	// a is just the virtual address, but should never be used
+	// directly. Call addr() to get this value instead.
+	a uintptr
+}
+
+// add adds a uintptr offset to the offAddr.
+func (l offAddr) add(bytes uintptr) offAddr {
+	return offAddr{a: l.a + bytes}
+}
+
+// sub subtracts a uintptr offset from the offAddr.
+func (l offAddr) sub(bytes uintptr) offAddr {
+	return offAddr{a: l.a - bytes}
+}
+
+// diff returns the amount of bytes in between the
+// two offAddrs.
+func (l1 offAddr) diff(l2 offAddr) uintptr {
+	return l1.a - l2.a
+}
+
+// lessThan returns true if l1 is less than l2 in the offset
+// address space.
+func (l1 offAddr) lessThan(l2 offAddr) bool {
+	return (l1.a - arenaBaseOffset) < (l2.a - arenaBaseOffset)
+}
+
+// lessEqual returns true if l1 is less than or equal to l2 in
+// the offset address space.
+func (l1 offAddr) lessEqual(l2 offAddr) bool {
+	return (l1.a - arenaBaseOffset) <= (l2.a - arenaBaseOffset)
+}
+
+// equal returns true if the two offAddr values are equal.
+func (l1 offAddr) equal(l2 offAddr) bool {
+	// No need to compare in the offset space, it
+	// means the same thing.
+	return l1 == l2
+}
+
+// addr returns the virtual address for this offset address.
+func (l offAddr) addr() uintptr {
+	return l.a
+}
+
+// atomicOffAddr is like offAddr, but operations on it are atomic.
+// It also contains operations to be able to store marked addresses
+// to ensure that they're not overridden until they've been seen.
+type atomicOffAddr struct {
+	// a contains the offset address, unlike offAddr.
+	a atomic.Int64
+}
+
+// Clear attempts to store minOffAddr in atomicOffAddr. It may fail
+// if a marked value is placed in the box in the meanwhile.
+func (b *atomicOffAddr) Clear() {
+	for {
+		old := b.a.Load()
+		if old < 0 {
+			return
+		}
+		if b.a.CompareAndSwap(old, int64(minOffAddr.addr()-arenaBaseOffset)) {
+			return
+		}
+	}
+}
+
+// StoreMin stores addr if it's less than the current value in the
+// offset address space if the current value is not marked.
+func (b *atomicOffAddr) StoreMin(addr uintptr) {
+	new := int64(addr - arenaBaseOffset)
+	for {
+		old := b.a.Load()
+		if old < new {
+			return
+		}
+		if b.a.CompareAndSwap(old, new) {
+			return
+		}
+	}
+}
+
+// StoreUnmark attempts to unmark the value in atomicOffAddr and
+// replace it with newAddr. markedAddr must be a marked address
+// returned by Load. This function will not store newAddr if the
+// box no longer contains markedAddr.
+func (b *atomicOffAddr) StoreUnmark(markedAddr, newAddr uintptr) {
+	b.a.CompareAndSwap(-int64(markedAddr-arenaBaseOffset), int64(newAddr-arenaBaseOffset))
+}
+
+// StoreMarked stores addr but first converted to the offset address
+// space and then negated.
+func (b *atomicOffAddr) StoreMarked(addr uintptr) {
+	b.a.Store(-int64(addr - arenaBaseOffset))
+}
+
+// Load returns the address in the box as a virtual address. It also
+// returns if the value was marked or not.
+func (b *atomicOffAddr) Load() (uintptr, bool) {
+	v := b.a.Load()
+	wasMarked := false
+	if v < 0 {
+		wasMarked = true
+		v = -v
+	}
+	return uintptr(v) + arenaBaseOffset, wasMarked
+}
+
+// addrRanges is a data structure holding a collection of ranges of
+// address space.
+//
+// The ranges are coalesced eagerly to reduce the
+// number ranges it holds.
+//
+// The slice backing store for this field is persistentalloc'd
+// and thus there is no way to free it.
+//
+// addrRanges is not thread-safe.
+type addrRanges struct {
+	// ranges is a slice of ranges sorted by base.
+	ranges []addrRange
+
+	// totalBytes is the total amount of address space in bytes counted by
+	// this addrRanges.
+	totalBytes uintptr
+
+	// sysStat is the stat to track allocations by this type
+	sysStat *sysMemStat
+}
+
+func (a *addrRanges) init(sysStat *sysMemStat) {
+	ranges := (*notInHeapSlice)(unsafe.Pointer(&a.ranges))
+	ranges.len = 0
+	ranges.cap = 16
+	ranges.array = (*notInHeap)(persistentalloc(unsafe.Sizeof(addrRange{})*uintptr(ranges.cap), goarch.PtrSize, sysStat))
+	a.sysStat = sysStat
+	a.totalBytes = 0
+}
+
+// findSucc returns the first index in a such that addr is
+// less than the base of the addrRange at that index.
+func (a *addrRanges) findSucc(addr uintptr) int {
+	base := offAddr{addr}
+
+	// Narrow down the search space via a binary search
+	// for large addrRanges until we have at most iterMax
+	// candidates left.
+	const iterMax = 8
+	bot, top := 0, len(a.ranges)
+	for top-bot > iterMax {
+		i := ((top - bot) / 2) + bot
+		if a.ranges[i].contains(base.addr()) {
+			// a.ranges[i] contains base, so
+			// its successor is the next index.
+			return i + 1
+		}
+		if base.lessThan(a.ranges[i].base) {
+			// In this case i might actually be
+			// the successor, but we can't be sure
+			// until we check the ones before it.
+			top = i
+		} else {
+			// In this case we know base is
+			// greater than or equal to a.ranges[i].limit-1,
+			// so i is definitely not the successor.
+			// We already checked i, so pick the next
+			// one.
+			bot = i + 1
+		}
+	}
+	// There are top-bot candidates left, so
+	// iterate over them and find the first that
+	// base is strictly less than.
+	for i := bot; i < top; i++ {
+		if base.lessThan(a.ranges[i].base) {
+			return i
+		}
+	}
+	return top
+}
+
+// findAddrGreaterEqual returns the smallest address represented by a
+// that is >= addr. Thus, if the address is represented by a,
+// then it returns addr. The second return value indicates whether
+// such an address exists for addr in a. That is, if addr is larger than
+// any address known to a, the second return value will be false.
+func (a *addrRanges) findAddrGreaterEqual(addr uintptr) (uintptr, bool) {
+	i := a.findSucc(addr)
+	if i == 0 {
+		return a.ranges[0].base.addr(), true
+	}
+	if a.ranges[i-1].contains(addr) {
+		return addr, true
+	}
+	if i < len(a.ranges) {
+		return a.ranges[i].base.addr(), true
+	}
+	return 0, false
+}
+
+// contains returns true if a covers the address addr.
+func (a *addrRanges) contains(addr uintptr) bool {
+	i := a.findSucc(addr)
+	if i == 0 {
+		return false
+	}
+	return a.ranges[i-1].contains(addr)
+}
+
+// add inserts a new address range to a.
+//
+// r must not overlap with any address range in a and r.size() must be > 0.
+func (a *addrRanges) add(r addrRange) {
+	// The copies in this function are potentially expensive, but this data
+	// structure is meant to represent the Go heap. At worst, copying this
+	// would take ~160µs assuming a conservative copying rate of 25 GiB/s (the
+	// copy will almost never trigger a page fault) for a 1 TiB heap with 4 MiB
+	// arenas which is completely discontiguous. ~160µs is still a lot, but in
+	// practice most platforms have 64 MiB arenas (which cuts this by a factor
+	// of 16) and Go heaps are usually mostly contiguous, so the chance that
+	// an addrRanges even grows to that size is extremely low.
+
+	// An empty range has no effect on the set of addresses represented
+	// by a, but passing a zero-sized range is almost always a bug.
+	if r.size() == 0 {
+		print("runtime: range = {", hex(r.base.addr()), ", ", hex(r.limit.addr()), "}\n")
+		throw("attempted to add zero-sized address range")
+	}
+	// Because we assume r is not currently represented in a,
+	// findSucc gives us our insertion index.
+	i := a.findSucc(r.base.addr())
+	coalescesDown := i > 0 && a.ranges[i-1].limit.equal(r.base)
+	coalescesUp := i < len(a.ranges) && r.limit.equal(a.ranges[i].base)
+	if coalescesUp && coalescesDown {
+		// We have neighbors and they both border us.
+		// Merge a.ranges[i-1], r, and a.ranges[i] together into a.ranges[i-1].
+		a.ranges[i-1].limit = a.ranges[i].limit
+
+		// Delete a.ranges[i].
+		copy(a.ranges[i:], a.ranges[i+1:])
+		a.ranges = a.ranges[:len(a.ranges)-1]
+	} else if coalescesDown {
+		// We have a neighbor at a lower address only and it borders us.
+		// Merge the new space into a.ranges[i-1].
+		a.ranges[i-1].limit = r.limit
+	} else if coalescesUp {
+		// We have a neighbor at a higher address only and it borders us.
+		// Merge the new space into a.ranges[i].
+		a.ranges[i].base = r.base
+	} else {
+		// We may or may not have neighbors which don't border us.
+		// Add the new range.
+		if len(a.ranges)+1 > cap(a.ranges) {
+			// Grow the array. Note that this leaks the old array, but since
+			// we're doubling we have at most 2x waste. For a 1 TiB heap and
+			// 4 MiB arenas which are all discontiguous (both very conservative
+			// assumptions), this would waste at most 4 MiB of memory.
+			oldRanges := a.ranges
+			ranges := (*notInHeapSlice)(unsafe.Pointer(&a.ranges))
+			ranges.len = len(oldRanges) + 1
+			ranges.cap = cap(oldRanges) * 2
+			ranges.array = (*notInHeap)(persistentalloc(unsafe.Sizeof(addrRange{})*uintptr(ranges.cap), goarch.PtrSize, a.sysStat))
+
+			// Copy in the old array, but make space for the new range.
+			copy(a.ranges[:i], oldRanges[:i])
+			copy(a.ranges[i+1:], oldRanges[i:])
+		} else {
+			a.ranges = a.ranges[:len(a.ranges)+1]
+			copy(a.ranges[i+1:], a.ranges[i:])
+		}
+		a.ranges[i] = r
+	}
+	a.totalBytes += r.size()
+}
+
+// removeLast removes and returns the highest-addressed contiguous range
+// of a, or the last nBytes of that range, whichever is smaller. If a is
+// empty, it returns an empty range.
+func (a *addrRanges) removeLast(nBytes uintptr) addrRange {
+	if len(a.ranges) == 0 {
+		return addrRange{}
+	}
+	r := a.ranges[len(a.ranges)-1]
+	size := r.size()
+	if size > nBytes {
+		newEnd := r.limit.sub(nBytes)
+		a.ranges[len(a.ranges)-1].limit = newEnd
+		a.totalBytes -= nBytes
+		return addrRange{newEnd, r.limit}
+	}
+	a.ranges = a.ranges[:len(a.ranges)-1]
+	a.totalBytes -= size
+	return r
+}
+
+// removeGreaterEqual removes the ranges of a which are above addr, and additionally
+// splits any range containing addr.
+func (a *addrRanges) removeGreaterEqual(addr uintptr) {
+	pivot := a.findSucc(addr)
+	if pivot == 0 {
+		// addr is before all ranges in a.
+		a.totalBytes = 0
+		a.ranges = a.ranges[:0]
+		return
+	}
+	removed := uintptr(0)
+	for _, r := range a.ranges[pivot:] {
+		removed += r.size()
+	}
+	if r := a.ranges[pivot-1]; r.contains(addr) {
+		removed += r.size()
+		r = r.removeGreaterEqual(addr)
+		if r.size() == 0 {
+			pivot--
+		} else {
+			removed -= r.size()
+			a.ranges[pivot-1] = r
+		}
+	}
+	a.ranges = a.ranges[:pivot]
+	a.totalBytes -= removed
+}
+
+// cloneInto makes a deep clone of a's state into b, re-using
+// b's ranges if able.
+func (a *addrRanges) cloneInto(b *addrRanges) {
+	if len(a.ranges) > cap(b.ranges) {
+		// Grow the array.
+		ranges := (*notInHeapSlice)(unsafe.Pointer(&b.ranges))
+		ranges.len = 0
+		ranges.cap = cap(a.ranges)
+		ranges.array = (*notInHeap)(persistentalloc(unsafe.Sizeof(addrRange{})*uintptr(ranges.cap), goarch.PtrSize, b.sysStat))
+	}
+	b.ranges = b.ranges[:len(a.ranges)]
+	b.totalBytes = a.totalBytes
+	copy(b.ranges, a.ranges)
+}
diff --git a/contrib/go/_std_1.18/src/runtime/msan0.go b/contrib/go/_std_1.19/src/runtime/msan0.go
index 2f5fd2d982..2f5fd2d982 100644
--- a/contrib/go/_std_1.18/src/runtime/msan0.go
+++ b/contrib/go/_std_1.19/src/runtime/msan0.go
diff --git a/contrib/go/_std_1.18/src/runtime/msize.go b/contrib/go/_std_1.19/src/runtime/msize.go
index c56aa5a7b2..c56aa5a7b2 100644
--- a/contrib/go/_std_1.18/src/runtime/msize.go
+++ b/contrib/go/_std_1.19/src/runtime/msize.go
diff --git a/contrib/go/_std_1.19/src/runtime/mspanset.go b/contrib/go/_std_1.19/src/runtime/mspanset.go
new file mode 100644
index 0000000000..4158495ddd
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/mspanset.go
@@ -0,0 +1,354 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"internal/cpu"
+	"internal/goarch"
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+// A spanSet is a set of *mspans.
+//
+// spanSet is safe for concurrent push and pop operations.
+type spanSet struct {
+	// A spanSet is a two-level data structure consisting of a
+	// growable spine that points to fixed-sized blocks. The spine
+	// can be accessed without locks, but adding a block or
+	// growing it requires taking the spine lock.
+	//
+	// Because each mspan covers at least 8K of heap and takes at
+	// most 8 bytes in the spanSet, the growth of the spine is
+	// quite limited.
+	//
+	// The spine and all blocks are allocated off-heap, which
+	// allows this to be used in the memory manager and avoids the
+	// need for write barriers on all of these. spanSetBlocks are
+	// managed in a pool, though never freed back to the operating
+	// system. We never release spine memory because there could be
+	// concurrent lock-free access and we're likely to reuse it
+	// anyway. (In principle, we could do this during STW.)
+
+	spineLock mutex
+	spine     unsafe.Pointer // *[N]*spanSetBlock, accessed atomically
+	spineLen  uintptr        // Spine array length, accessed atomically
+	spineCap  uintptr        // Spine array cap, accessed under lock
+
+	// index is the head and tail of the spanSet in a single field.
+	// The head and the tail both represent an index into the logical
+	// concatenation of all blocks, with the head always behind or
+	// equal to the tail (indicating an empty set). This field is
+	// always accessed atomically.
+	//
+	// The head and the tail are only 32 bits wide, which means we
+	// can only support up to 2^32 pushes before a reset. If every
+	// span in the heap were stored in this set, and each span were
+	// the minimum size (1 runtime page, 8 KiB), then roughly the
+	// smallest heap which would be unrepresentable is 32 TiB in size.
+	index headTailIndex
+}
+
+const (
+	spanSetBlockEntries = 512 // 4KB on 64-bit
+	spanSetInitSpineCap = 256 // Enough for 1GB heap on 64-bit
+)
+
+type spanSetBlock struct {
+	// Free spanSetBlocks are managed via a lock-free stack.
+	lfnode
+
+	// popped is the number of pop operations that have occurred on
+	// this block. This number is used to help determine when a block
+	// may be safely recycled.
+	popped uint32
+
+	// spans is the set of spans in this block.
+	spans [spanSetBlockEntries]*mspan
+}
+
+// push adds span s to buffer b. push is safe to call concurrently
+// with other push and pop operations.
+func (b *spanSet) push(s *mspan) {
+	// Obtain our slot.
+	cursor := uintptr(b.index.incTail().tail() - 1)
+	top, bottom := cursor/spanSetBlockEntries, cursor%spanSetBlockEntries
+
+	// Do we need to add a block?
+	spineLen := atomic.Loaduintptr(&b.spineLen)
+	var block *spanSetBlock
+retry:
+	if top < spineLen {
+		spine := atomic.Loadp(unsafe.Pointer(&b.spine))
+		blockp := add(spine, goarch.PtrSize*top)
+		block = (*spanSetBlock)(atomic.Loadp(blockp))
+	} else {
+		// Add a new block to the spine, potentially growing
+		// the spine.
+		lock(&b.spineLock)
+		// spineLen cannot change until we release the lock,
+		// but may have changed while we were waiting.
+		spineLen = atomic.Loaduintptr(&b.spineLen)
+		if top < spineLen {
+			unlock(&b.spineLock)
+			goto retry
+		}
+
+		if spineLen == b.spineCap {
+			// Grow the spine.
+			newCap := b.spineCap * 2
+			if newCap == 0 {
+				newCap = spanSetInitSpineCap
+			}
+			newSpine := persistentalloc(newCap*goarch.PtrSize, cpu.CacheLineSize, &memstats.gcMiscSys)
+			if b.spineCap != 0 {
+				// Blocks are allocated off-heap, so
+				// no write barriers.
+				memmove(newSpine, b.spine, b.spineCap*goarch.PtrSize)
+			}
+			// Spine is allocated off-heap, so no write barrier.
+			atomic.StorepNoWB(unsafe.Pointer(&b.spine), newSpine)
+			b.spineCap = newCap
+			// We can't immediately free the old spine
+			// since a concurrent push with a lower index
+			// could still be reading from it. We let it
+			// leak because even a 1TB heap would waste
+			// less than 2MB of memory on old spines. If
+			// this is a problem, we could free old spines
+			// during STW.
+		}
+
+		// Allocate a new block from the pool.
+		block = spanSetBlockPool.alloc()
+
+		// Add it to the spine.
+		blockp := add(b.spine, goarch.PtrSize*top)
+		// Blocks are allocated off-heap, so no write barrier.
+		atomic.StorepNoWB(blockp, unsafe.Pointer(block))
+		atomic.Storeuintptr(&b.spineLen, spineLen+1)
+		unlock(&b.spineLock)
+	}
+
+	// We have a block. Insert the span atomically, since there may be
+	// concurrent readers via the block API.
+	atomic.StorepNoWB(unsafe.Pointer(&block.spans[bottom]), unsafe.Pointer(s))
+}
+
+// pop removes and returns a span from buffer b, or nil if b is empty.
+// pop is safe to call concurrently with other pop and push operations.
+func (b *spanSet) pop() *mspan {
+	var head, tail uint32
+claimLoop:
+	for {
+		headtail := b.index.load()
+		head, tail = headtail.split()
+		if head >= tail {
+			// The buf is empty, as far as we can tell.
+			return nil
+		}
+		// Check if the head position we want to claim is actually
+		// backed by a block.
+		spineLen := atomic.Loaduintptr(&b.spineLen)
+		if spineLen <= uintptr(head)/spanSetBlockEntries {
+			// We're racing with a spine growth and the allocation of
+			// a new block (and maybe a new spine!), and trying to grab
+			// the span at the index which is currently being pushed.
+			// Instead of spinning, let's just notify the caller that
+			// there's nothing currently here. Spinning on this is
+			// almost definitely not worth it.
+			return nil
+		}
+		// Try to claim the current head by CASing in an updated head.
+		// This may fail transiently due to a push which modifies the
+		// tail, so keep trying while the head isn't changing.
+		want := head
+		for want == head {
+			if b.index.cas(headtail, makeHeadTailIndex(want+1, tail)) {
+				break claimLoop
+			}
+			headtail = b.index.load()
+			head, tail = headtail.split()
+		}
+		// We failed to claim the spot we were after and the head changed,
+		// meaning a popper got ahead of us. Try again from the top because
+		// the buf may not be empty.
+	}
+	top, bottom := head/spanSetBlockEntries, head%spanSetBlockEntries
+
+	// We may be reading a stale spine pointer, but because the length
+	// grows monotonically and we've already verified it, we'll definitely
+	// be reading from a valid block.
+	spine := atomic.Loadp(unsafe.Pointer(&b.spine))
+	blockp := add(spine, goarch.PtrSize*uintptr(top))
+
+	// Given that the spine length is correct, we know we will never
+	// see a nil block here, since the length is always updated after
+	// the block is set.
+	block := (*spanSetBlock)(atomic.Loadp(blockp))
+	s := (*mspan)(atomic.Loadp(unsafe.Pointer(&block.spans[bottom])))
+	for s == nil {
+		// We raced with the span actually being set, but given that we
+		// know a block for this span exists, the race window here is
+		// extremely small. Try again.
+		s = (*mspan)(atomic.Loadp(unsafe.Pointer(&block.spans[bottom])))
+	}
+	// Clear the pointer. This isn't strictly necessary, but defensively
+	// avoids accidentally re-using blocks which could lead to memory
+	// corruption. This way, we'll get a nil pointer access instead.
+	atomic.StorepNoWB(unsafe.Pointer(&block.spans[bottom]), nil)
+
+	// Increase the popped count. If we are the last possible popper
+	// in the block (note that bottom need not equal spanSetBlockEntries-1
+	// due to races) then it's our responsibility to free the block.
+	//
+	// If we increment popped to spanSetBlockEntries, we can be sure that
+	// we're the last popper for this block, and it's thus safe to free it.
+	// Every other popper must have crossed this barrier (and thus finished
+	// popping its corresponding mspan) by the time we get here. Because
+	// we're the last popper, we also don't have to worry about concurrent
+	// pushers (there can't be any). Note that we may not be the popper
+	// which claimed the last slot in the block, we're just the last one
+	// to finish popping.
+	if atomic.Xadd(&block.popped, 1) == spanSetBlockEntries {
+		// Clear the block's pointer.
+		atomic.StorepNoWB(blockp, nil)
+
+		// Return the block to the block pool.
+		spanSetBlockPool.free(block)
+	}
+	return s
+}
+
+// reset resets a spanSet which is empty. It will also clean up
+// any left over blocks.
+//
+// Throws if the buf is not empty.
+//
+// reset may not be called concurrently with any other operations
+// on the span set.
+func (b *spanSet) reset() {
+	head, tail := b.index.load().split()
+	if head < tail {
+		print("head = ", head, ", tail = ", tail, "\n")
+		throw("attempt to clear non-empty span set")
+	}
+	top := head / spanSetBlockEntries
+	if uintptr(top) < b.spineLen {
+		// If the head catches up to the tail and the set is empty,
+		// we may not clean up the block containing the head and tail
+		// since it may be pushed into again. In order to avoid leaking
+		// memory since we're going to reset the head and tail, clean
+		// up such a block now, if it exists.
+		blockp := (**spanSetBlock)(add(b.spine, goarch.PtrSize*uintptr(top)))
+		block := *blockp
+		if block != nil {
+			// Sanity check the popped value.
+			if block.popped == 0 {
+				// popped should never be zero because that means we have
+				// pushed at least one value but not yet popped if this
+				// block pointer is not nil.
+				throw("span set block with unpopped elements found in reset")
+			}
+			if block.popped == spanSetBlockEntries {
+				// popped should also never be equal to spanSetBlockEntries
+				// because the last popper should have made the block pointer
+				// in this slot nil.
+				throw("fully empty unfreed span set block found in reset")
+			}
+
+			// Clear the pointer to the block.
+			atomic.StorepNoWB(unsafe.Pointer(blockp), nil)
+
+			// Return the block to the block pool.
+			spanSetBlockPool.free(block)
+		}
+	}
+	b.index.reset()
+	atomic.Storeuintptr(&b.spineLen, 0)
+}
+
+// spanSetBlockPool is a global pool of spanSetBlocks.
+var spanSetBlockPool spanSetBlockAlloc
+
+// spanSetBlockAlloc represents a concurrent pool of spanSetBlocks.
+type spanSetBlockAlloc struct {
+	stack lfstack
+}
+
+// alloc tries to grab a spanSetBlock out of the pool, and if it fails
+// persistentallocs a new one and returns it.
+func (p *spanSetBlockAlloc) alloc() *spanSetBlock {
+	if s := (*spanSetBlock)(p.stack.pop()); s != nil {
+		return s
+	}
+	return (*spanSetBlock)(persistentalloc(unsafe.Sizeof(spanSetBlock{}), cpu.CacheLineSize, &memstats.gcMiscSys))
+}
+
+// free returns a spanSetBlock back to the pool.
+func (p *spanSetBlockAlloc) free(block *spanSetBlock) {
+	atomic.Store(&block.popped, 0)
+	p.stack.push(&block.lfnode)
+}
+
+// haidTailIndex represents a combined 32-bit head and 32-bit tail
+// of a queue into a single 64-bit value.
+type headTailIndex uint64
+
+// makeHeadTailIndex creates a headTailIndex value from a separate
+// head and tail.
+func makeHeadTailIndex(head, tail uint32) headTailIndex {
+	return headTailIndex(uint64(head)<<32 | uint64(tail))
+}
+
+// head returns the head of a headTailIndex value.
+func (h headTailIndex) head() uint32 {
+	return uint32(h >> 32)
+}
+
+// tail returns the tail of a headTailIndex value.
+func (h headTailIndex) tail() uint32 {
+	return uint32(h)
+}
+
+// split splits the headTailIndex value into its parts.
+func (h headTailIndex) split() (head uint32, tail uint32) {
+	return h.head(), h.tail()
+}
+
+// load atomically reads a headTailIndex value.
+func (h *headTailIndex) load() headTailIndex {
+	return headTailIndex(atomic.Load64((*uint64)(h)))
+}
+
+// cas atomically compares-and-swaps a headTailIndex value.
+func (h *headTailIndex) cas(old, new headTailIndex) bool {
+	return atomic.Cas64((*uint64)(h), uint64(old), uint64(new))
+}
+
+// incHead atomically increments the head of a headTailIndex.
+func (h *headTailIndex) incHead() headTailIndex {
+	return headTailIndex(atomic.Xadd64((*uint64)(h), (1 << 32)))
+}
+
+// decHead atomically decrements the head of a headTailIndex.
+func (h *headTailIndex) decHead() headTailIndex {
+	return headTailIndex(atomic.Xadd64((*uint64)(h), -(1 << 32)))
+}
+
+// incTail atomically increments the tail of a headTailIndex.
+func (h *headTailIndex) incTail() headTailIndex {
+	ht := headTailIndex(atomic.Xadd64((*uint64)(h), +1))
+	// Check for overflow.
+	if ht.tail() == 0 {
+		print("runtime: head = ", ht.head(), ", tail = ", ht.tail(), "\n")
+		throw("headTailIndex overflow")
+	}
+	return ht
+}
+
+// reset clears the headTailIndex to (0, 0).
+func (h *headTailIndex) reset() {
+	atomic.Store64((*uint64)(h), 0)
+}
diff --git a/contrib/go/_std_1.19/src/runtime/mstats.go b/contrib/go/_std_1.19/src/runtime/mstats.go
new file mode 100644
index 0000000000..0029ea956c
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/mstats.go
@@ -0,0 +1,888 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Memory statistics
+
+package runtime
+
+import (
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+type mstats struct {
+	// Statistics about malloc heap.
+	heapStats consistentHeapStats
+
+	// Statistics about stacks.
+	stacks_sys sysMemStat // only counts newosproc0 stack in mstats; differs from MemStats.StackSys
+
+	// Statistics about allocation of low-level fixed-size structures.
+	mspan_sys    sysMemStat
+	mcache_sys   sysMemStat
+	buckhash_sys sysMemStat // profiling bucket hash table
+
+	// Statistics about GC overhead.
+	gcMiscSys sysMemStat // updated atomically or during STW
+
+	// Miscellaneous statistics.
+	other_sys sysMemStat // updated atomically or during STW
+
+	// Statistics about the garbage collector.
+
+	// Protected by mheap or stopping the world during GC.
+	last_gc_unix    uint64 // last gc (in unix time)
+	pause_total_ns  uint64
+	pause_ns        [256]uint64 // circular buffer of recent gc pause lengths
+	pause_end       [256]uint64 // circular buffer of recent gc end times (nanoseconds since 1970)
+	numgc           uint32
+	numforcedgc     uint32  // number of user-forced GCs
+	gc_cpu_fraction float64 // fraction of CPU time used by GC
+
+	last_gc_nanotime uint64 // last gc (monotonic time)
+	lastHeapInUse    uint64 // heapInUse at mark termination of the previous GC
+
+	enablegc bool
+
+	_ uint32 // ensure gcPauseDist is aligned.
+
+	// gcPauseDist represents the distribution of all GC-related
+	// application pauses in the runtime.
+	//
+	// Each individual pause is counted separately, unlike pause_ns.
+	gcPauseDist timeHistogram
+}
+
+var memstats mstats
+
+// A MemStats records statistics about the memory allocator.
+type MemStats struct {
+	// General statistics.
+
+	// Alloc is bytes of allocated heap objects.
+	//
+	// This is the same as HeapAlloc (see below).
+	Alloc uint64
+
+	// TotalAlloc is cumulative bytes allocated for heap objects.
+	//
+	// TotalAlloc increases as heap objects are allocated, but
+	// unlike Alloc and HeapAlloc, it does not decrease when
+	// objects are freed.
+	TotalAlloc uint64
+
+	// Sys is the total bytes of memory obtained from the OS.
+	//
+	// Sys is the sum of the XSys fields below. Sys measures the
+	// virtual address space reserved by the Go runtime for the
+	// heap, stacks, and other internal data structures. It's
+	// likely that not all of the virtual address space is backed
+	// by physical memory at any given moment, though in general
+	// it all was at some point.
+	Sys uint64
+
+	// Lookups is the number of pointer lookups performed by the
+	// runtime.
+	//
+	// This is primarily useful for debugging runtime internals.
+	Lookups uint64
+
+	// Mallocs is the cumulative count of heap objects allocated.
+	// The number of live objects is Mallocs - Frees.
+	Mallocs uint64
+
+	// Frees is the cumulative count of heap objects freed.
+	Frees uint64
+
+	// Heap memory statistics.
+	//
+	// Interpreting the heap statistics requires some knowledge of
+	// how Go organizes memory. Go divides the virtual address
+	// space of the heap into "spans", which are contiguous
+	// regions of memory 8K or larger. A span may be in one of
+	// three states:
+	//
+	// An "idle" span contains no objects or other data. The
+	// physical memory backing an idle span can be released back
+	// to the OS (but the virtual address space never is), or it
+	// can be converted into an "in use" or "stack" span.
+	//
+	// An "in use" span contains at least one heap object and may
+	// have free space available to allocate more heap objects.
+	//
+	// A "stack" span is used for goroutine stacks. Stack spans
+	// are not considered part of the heap. A span can change
+	// between heap and stack memory; it is never used for both
+	// simultaneously.
+
+	// HeapAlloc is bytes of allocated heap objects.
+	//
+	// "Allocated" heap objects include all reachable objects, as
+	// well as unreachable objects that the garbage collector has
+	// not yet freed. Specifically, HeapAlloc increases as heap
+	// objects are allocated and decreases as the heap is swept
+	// and unreachable objects are freed. Sweeping occurs
+	// incrementally between GC cycles, so these two processes
+	// occur simultaneously, and as a result HeapAlloc tends to
+	// change smoothly (in contrast with the sawtooth that is
+	// typical of stop-the-world garbage collectors).
+	HeapAlloc uint64
+
+	// HeapSys is bytes of heap memory obtained from the OS.
+	//
+	// HeapSys measures the amount of virtual address space
+	// reserved for the heap. This includes virtual address space
+	// that has been reserved but not yet used, which consumes no
+	// physical memory, but tends to be small, as well as virtual
+	// address space for which the physical memory has been
+	// returned to the OS after it became unused (see HeapReleased
+	// for a measure of the latter).
+	//
+	// HeapSys estimates the largest size the heap has had.
+	HeapSys uint64
+
+	// HeapIdle is bytes in idle (unused) spans.
+	//
+	// Idle spans have no objects in them. These spans could be
+	// (and may already have been) returned to the OS, or they can
+	// be reused for heap allocations, or they can be reused as
+	// stack memory.
+	//
+	// HeapIdle minus HeapReleased estimates the amount of memory
+	// that could be returned to the OS, but is being retained by
+	// the runtime so it can grow the heap without requesting more
+	// memory from the OS. If this difference is significantly
+	// larger than the heap size, it indicates there was a recent
+	// transient spike in live heap size.
+	HeapIdle uint64
+
+	// HeapInuse is bytes in in-use spans.
+	//
+	// In-use spans have at least one object in them. These spans
+	// can only be used for other objects of roughly the same
+	// size.
+	//
+	// HeapInuse minus HeapAlloc estimates the amount of memory
+	// that has been dedicated to particular size classes, but is
+	// not currently being used. This is an upper bound on
+	// fragmentation, but in general this memory can be reused
+	// efficiently.
+	HeapInuse uint64
+
+	// HeapReleased is bytes of physical memory returned to the OS.
+	//
+	// This counts heap memory from idle spans that was returned
+	// to the OS and has not yet been reacquired for the heap.
+	HeapReleased uint64
+
+	// HeapObjects is the number of allocated heap objects.
+	//
+	// Like HeapAlloc, this increases as objects are allocated and
+	// decreases as the heap is swept and unreachable objects are
+	// freed.
+	HeapObjects uint64
+
+	// Stack memory statistics.
+	//
+	// Stacks are not considered part of the heap, but the runtime
+	// can reuse a span of heap memory for stack memory, and
+	// vice-versa.
+
+	// StackInuse is bytes in stack spans.
+	//
+	// In-use stack spans have at least one stack in them. These
+	// spans can only be used for other stacks of the same size.
+	//
+	// There is no StackIdle because unused stack spans are
+	// returned to the heap (and hence counted toward HeapIdle).
+	StackInuse uint64
+
+	// StackSys is bytes of stack memory obtained from the OS.
+	//
+	// StackSys is StackInuse, plus any memory obtained directly
+	// from the OS for OS thread stacks (which should be minimal).
+	StackSys uint64
+
+	// Off-heap memory statistics.
+	//
+	// The following statistics measure runtime-internal
+	// structures that are not allocated from heap memory (usually
+	// because they are part of implementing the heap). Unlike
+	// heap or stack memory, any memory allocated to these
+	// structures is dedicated to these structures.
+	//
+	// These are primarily useful for debugging runtime memory
+	// overheads.
+
+	// MSpanInuse is bytes of allocated mspan structures.
+	MSpanInuse uint64
+
+	// MSpanSys is bytes of memory obtained from the OS for mspan
+	// structures.
+	MSpanSys uint64
+
+	// MCacheInuse is bytes of allocated mcache structures.
+	MCacheInuse uint64
+
+	// MCacheSys is bytes of memory obtained from the OS for
+	// mcache structures.
+	MCacheSys uint64
+
+	// BuckHashSys is bytes of memory in profiling bucket hash tables.
+	BuckHashSys uint64
+
+	// GCSys is bytes of memory in garbage collection metadata.
+	GCSys uint64
+
+	// OtherSys is bytes of memory in miscellaneous off-heap
+	// runtime allocations.
+	OtherSys uint64
+
+	// Garbage collector statistics.
+
+	// NextGC is the target heap size of the next GC cycle.
+	//
+	// The garbage collector's goal is to keep HeapAlloc ≤ NextGC.
+	// At the end of each GC cycle, the target for the next cycle
+	// is computed based on the amount of reachable data and the
+	// value of GOGC.
+	NextGC uint64
+
+	// LastGC is the time the last garbage collection finished, as
+	// nanoseconds since 1970 (the UNIX epoch).
+	LastGC uint64
+
+	// PauseTotalNs is the cumulative nanoseconds in GC
+	// stop-the-world pauses since the program started.
+	//
+	// During a stop-the-world pause, all goroutines are paused
+	// and only the garbage collector can run.
+	PauseTotalNs uint64
+
+	// PauseNs is a circular buffer of recent GC stop-the-world
+	// pause times in nanoseconds.
+	//
+	// The most recent pause is at PauseNs[(NumGC+255)%256]. In
+	// general, PauseNs[N%256] records the time paused in the most
+	// recent N%256th GC cycle. There may be multiple pauses per
+	// GC cycle; this is the sum of all pauses during a cycle.
+	PauseNs [256]uint64
+
+	// PauseEnd is a circular buffer of recent GC pause end times,
+	// as nanoseconds since 1970 (the UNIX epoch).
+	//
+	// This buffer is filled the same way as PauseNs. There may be
+	// multiple pauses per GC cycle; this records the end of the
+	// last pause in a cycle.
+	PauseEnd [256]uint64
+
+	// NumGC is the number of completed GC cycles.
+	NumGC uint32
+
+	// NumForcedGC is the number of GC cycles that were forced by
+	// the application calling the GC function.
+	NumForcedGC uint32
+
+	// GCCPUFraction is the fraction of this program's available
+	// CPU time used by the GC since the program started.
+	//
+	// GCCPUFraction is expressed as a number between 0 and 1,
+	// where 0 means GC has consumed none of this program's CPU. A
+	// program's available CPU time is defined as the integral of
+	// GOMAXPROCS since the program started. That is, if
+	// GOMAXPROCS is 2 and a program has been running for 10
+	// seconds, its "available CPU" is 20 seconds. GCCPUFraction
+	// does not include CPU time used for write barrier activity.
+	//
+	// This is the same as the fraction of CPU reported by
+	// GODEBUG=gctrace=1.
+	GCCPUFraction float64
+
+	// EnableGC indicates that GC is enabled. It is always true,
+	// even if GOGC=off.
+	EnableGC bool
+
+	// DebugGC is currently unused.
+	DebugGC bool
+
+	// BySize reports per-size class allocation statistics.
+	//
+	// BySize[N] gives statistics for allocations of size S where
+	// BySize[N-1].Size < S ≤ BySize[N].Size.
+	//
+	// This does not report allocations larger than BySize[60].Size.
+	BySize [61]struct {
+		// Size is the maximum byte size of an object in this
+		// size class.
+		Size uint32
+
+		// Mallocs is the cumulative count of heap objects
+		// allocated in this size class. The cumulative bytes
+		// of allocation is Size*Mallocs. The number of live
+		// objects in this size class is Mallocs - Frees.
+		Mallocs uint64
+
+		// Frees is the cumulative count of heap objects freed
+		// in this size class.
+		Frees uint64
+	}
+}
+
+func init() {
+	if offset := unsafe.Offsetof(memstats.heapStats); offset%8 != 0 {
+		println(offset)
+		throw("memstats.heapStats not aligned to 8 bytes")
+	}
+	if offset := unsafe.Offsetof(memstats.gcPauseDist); offset%8 != 0 {
+		println(offset)
+		throw("memstats.gcPauseDist not aligned to 8 bytes")
+	}
+	// Ensure the size of heapStatsDelta causes adjacent fields/slots (e.g.
+	// [3]heapStatsDelta) to be 8-byte aligned.
+	if size := unsafe.Sizeof(heapStatsDelta{}); size%8 != 0 {
+		println(size)
+		throw("heapStatsDelta not a multiple of 8 bytes in size")
+	}
+}
+
+// ReadMemStats populates m with memory allocator statistics.
+//
+// The returned memory allocator statistics are up to date as of the
+// call to ReadMemStats. This is in contrast with a heap profile,
+// which is a snapshot as of the most recently completed garbage
+// collection cycle.
+func ReadMemStats(m *MemStats) {
+	stopTheWorld("read mem stats")
+
+	systemstack(func() {
+		readmemstats_m(m)
+	})
+
+	startTheWorld()
+}
+
+// readmemstats_m populates stats for internal runtime values.
+//
+// The world must be stopped.
+func readmemstats_m(stats *MemStats) {
+	assertWorldStopped()
+
+	// Flush mcaches to mcentral before doing anything else.
+	//
+	// Flushing to the mcentral may in general cause stats to
+	// change as mcentral data structures are manipulated.
+	systemstack(flushallmcaches)
+
+	// Calculate memory allocator stats.
+	// During program execution we only count number of frees and amount of freed memory.
+	// Current number of alive objects in the heap and amount of alive heap memory
+	// are calculated by scanning all spans.
+	// Total number of mallocs is calculated as number of frees plus number of alive objects.
+	// Similarly, total amount of allocated memory is calculated as amount of freed memory
+	// plus amount of alive heap memory.
+
+	// Collect consistent stats, which are the source-of-truth in some cases.
+	var consStats heapStatsDelta
+	memstats.heapStats.unsafeRead(&consStats)
+
+	// Collect large allocation stats.
+	totalAlloc := consStats.largeAlloc
+	nMalloc := consStats.largeAllocCount
+	totalFree := consStats.largeFree
+	nFree := consStats.largeFreeCount
+
+	// Collect per-sizeclass stats.
+	var bySize [_NumSizeClasses]struct {
+		Size    uint32
+		Mallocs uint64
+		Frees   uint64
+	}
+	for i := range bySize {
+		bySize[i].Size = uint32(class_to_size[i])
+
+		// Malloc stats.
+		a := consStats.smallAllocCount[i]
+		totalAlloc += a * uint64(class_to_size[i])
+		nMalloc += a
+		bySize[i].Mallocs = a
+
+		// Free stats.
+		f := consStats.smallFreeCount[i]
+		totalFree += f * uint64(class_to_size[i])
+		nFree += f
+		bySize[i].Frees = f
+	}
+
+	// Account for tiny allocations.
+	// For historical reasons, MemStats includes tiny allocations
+	// in both the total free and total alloc count. This double-counts
+	// memory in some sense because their tiny allocation block is also
+	// counted. Tracking the lifetime of individual tiny allocations is
+	// currently not done because it would be too expensive.
+	nFree += consStats.tinyAllocCount
+	nMalloc += consStats.tinyAllocCount
+
+	// Calculate derived stats.
+
+	stackInUse := uint64(consStats.inStacks)
+	gcWorkBufInUse := uint64(consStats.inWorkBufs)
+	gcProgPtrScalarBitsInUse := uint64(consStats.inPtrScalarBits)
+
+	totalMapped := gcController.heapInUse.load() + gcController.heapFree.load() + gcController.heapReleased.load() +
+		memstats.stacks_sys.load() + memstats.mspan_sys.load() + memstats.mcache_sys.load() +
+		memstats.buckhash_sys.load() + memstats.gcMiscSys.load() + memstats.other_sys.load() +
+		stackInUse + gcWorkBufInUse + gcProgPtrScalarBitsInUse
+
+	heapGoal := gcController.heapGoal()
+
+	// The world is stopped, so the consistent stats (after aggregation)
+	// should be identical to some combination of memstats. In particular:
+	//
+	// * memstats.heapInUse == inHeap
+	// * memstats.heapReleased == released
+	// * memstats.heapInUse + memstats.heapFree == committed - inStacks - inWorkBufs - inPtrScalarBits
+	// * memstats.totalAlloc == totalAlloc
+	// * memstats.totalFree == totalFree
+	//
+	// Check if that's actually true.
+	//
+	// TODO(mknyszek): Maybe don't throw here. It would be bad if a
+	// bug in otherwise benign accounting caused the whole application
+	// to crash.
+	if gcController.heapInUse.load() != uint64(consStats.inHeap) {
+		print("runtime: heapInUse=", gcController.heapInUse.load(), "\n")
+		print("runtime: consistent value=", consStats.inHeap, "\n")
+		throw("heapInUse and consistent stats are not equal")
+	}
+	if gcController.heapReleased.load() != uint64(consStats.released) {
+		print("runtime: heapReleased=", gcController.heapReleased.load(), "\n")
+		print("runtime: consistent value=", consStats.released, "\n")
+		throw("heapReleased and consistent stats are not equal")
+	}
+	heapRetained := gcController.heapInUse.load() + gcController.heapFree.load()
+	consRetained := uint64(consStats.committed - consStats.inStacks - consStats.inWorkBufs - consStats.inPtrScalarBits)
+	if heapRetained != consRetained {
+		print("runtime: global value=", heapRetained, "\n")
+		print("runtime: consistent value=", consRetained, "\n")
+		throw("measures of the retained heap are not equal")
+	}
+	if gcController.totalAlloc.Load() != totalAlloc {
+		print("runtime: totalAlloc=", gcController.totalAlloc.Load(), "\n")
+		print("runtime: consistent value=", totalAlloc, "\n")
+		throw("totalAlloc and consistent stats are not equal")
+	}
+	if gcController.totalFree.Load() != totalFree {
+		print("runtime: totalFree=", gcController.totalFree.Load(), "\n")
+		print("runtime: consistent value=", totalFree, "\n")
+		throw("totalFree and consistent stats are not equal")
+	}
+	// Also check that mappedReady lines up with totalMapped - released.
+	// This isn't really the same type of "make sure consistent stats line up" situation,
+	// but this is an opportune time to check.
+	if gcController.mappedReady.Load() != totalMapped-uint64(consStats.released) {
+		print("runtime: mappedReady=", gcController.mappedReady.Load(), "\n")
+		print("runtime: totalMapped=", totalMapped, "\n")
+		print("runtime: released=", uint64(consStats.released), "\n")
+		print("runtime: totalMapped-released=", totalMapped-uint64(consStats.released), "\n")
+		throw("mappedReady and other memstats are not equal")
+	}
+
+	// We've calculated all the values we need. Now, populate stats.
+
+	stats.Alloc = totalAlloc - totalFree
+	stats.TotalAlloc = totalAlloc
+	stats.Sys = totalMapped
+	stats.Mallocs = nMalloc
+	stats.Frees = nFree
+	stats.HeapAlloc = totalAlloc - totalFree
+	stats.HeapSys = gcController.heapInUse.load() + gcController.heapFree.load() + gcController.heapReleased.load()
+	// By definition, HeapIdle is memory that was mapped
+	// for the heap but is not currently used to hold heap
+	// objects. It also specifically is memory that can be
+	// used for other purposes, like stacks, but this memory
+	// is subtracted out of HeapSys before it makes that
+	// transition. Put another way:
+	//
+	// HeapSys = bytes allocated from the OS for the heap - bytes ultimately used for non-heap purposes
+	// HeapIdle = bytes allocated from the OS for the heap - bytes ultimately used for any purpose
+	//
+	// or
+	//
+	// HeapSys = sys - stacks_inuse - gcWorkBufInUse - gcProgPtrScalarBitsInUse
+	// HeapIdle = sys - stacks_inuse - gcWorkBufInUse - gcProgPtrScalarBitsInUse - heapInUse
+	//
+	// => HeapIdle = HeapSys - heapInUse = heapFree + heapReleased
+	stats.HeapIdle = gcController.heapFree.load() + gcController.heapReleased.load()
+	stats.HeapInuse = gcController.heapInUse.load()
+	stats.HeapReleased = gcController.heapReleased.load()
+	stats.HeapObjects = nMalloc - nFree
+	stats.StackInuse = stackInUse
+	// memstats.stacks_sys is only memory mapped directly for OS stacks.
+	// Add in heap-allocated stack memory for user consumption.
+	stats.StackSys = stackInUse + memstats.stacks_sys.load()
+	stats.MSpanInuse = uint64(mheap_.spanalloc.inuse)
+	stats.MSpanSys = memstats.mspan_sys.load()
+	stats.MCacheInuse = uint64(mheap_.cachealloc.inuse)
+	stats.MCacheSys = memstats.mcache_sys.load()
+	stats.BuckHashSys = memstats.buckhash_sys.load()
+	// MemStats defines GCSys as an aggregate of all memory related
+	// to the memory management system, but we track this memory
+	// at a more granular level in the runtime.
+	stats.GCSys = memstats.gcMiscSys.load() + gcWorkBufInUse + gcProgPtrScalarBitsInUse
+	stats.OtherSys = memstats.other_sys.load()
+	stats.NextGC = heapGoal
+	stats.LastGC = memstats.last_gc_unix
+	stats.PauseTotalNs = memstats.pause_total_ns
+	stats.PauseNs = memstats.pause_ns
+	stats.PauseEnd = memstats.pause_end
+	stats.NumGC = memstats.numgc
+	stats.NumForcedGC = memstats.numforcedgc
+	stats.GCCPUFraction = memstats.gc_cpu_fraction
+	stats.EnableGC = true
+
+	// stats.BySize and bySize might not match in length.
+	// That's OK, stats.BySize cannot change due to backwards
+	// compatibility issues. copy will copy the minimum amount
+	// of values between the two of them.
+	copy(stats.BySize[:], bySize[:])
+}
+
+//go:linkname readGCStats runtime/debug.readGCStats
+func readGCStats(pauses *[]uint64) {
+	systemstack(func() {
+		readGCStats_m(pauses)
+	})
+}
+
+// readGCStats_m must be called on the system stack because it acquires the heap
+// lock. See mheap for details.
+//
+//go:systemstack
+func readGCStats_m(pauses *[]uint64) {
+	p := *pauses
+	// Calling code in runtime/debug should make the slice large enough.
+	if cap(p) < len(memstats.pause_ns)+3 {
+		throw("short slice passed to readGCStats")
+	}
+
+	// Pass back: pauses, pause ends, last gc (absolute time), number of gc, total pause ns.
+	lock(&mheap_.lock)
+
+	n := memstats.numgc
+	if n > uint32(len(memstats.pause_ns)) {
+		n = uint32(len(memstats.pause_ns))
+	}
+
+	// The pause buffer is circular. The most recent pause is at
+	// pause_ns[(numgc-1)%len(pause_ns)], and then backward
+	// from there to go back farther in time. We deliver the times
+	// most recent first (in p[0]).
+	p = p[:cap(p)]
+	for i := uint32(0); i < n; i++ {
+		j := (memstats.numgc - 1 - i) % uint32(len(memstats.pause_ns))
+		p[i] = memstats.pause_ns[j]
+		p[n+i] = memstats.pause_end[j]
+	}
+
+	p[n+n] = memstats.last_gc_unix
+	p[n+n+1] = uint64(memstats.numgc)
+	p[n+n+2] = memstats.pause_total_ns
+	unlock(&mheap_.lock)
+	*pauses = p[:n+n+3]
+}
+
+// flushmcache flushes the mcache of allp[i].
+//
+// The world must be stopped.
+//
+//go:nowritebarrier
+func flushmcache(i int) {
+	assertWorldStopped()
+
+	p := allp[i]
+	c := p.mcache
+	if c == nil {
+		return
+	}
+	c.releaseAll()
+	stackcache_clear(c)
+}
+
+// flushallmcaches flushes the mcaches of all Ps.
+//
+// The world must be stopped.
+//
+//go:nowritebarrier
+func flushallmcaches() {
+	assertWorldStopped()
+
+	for i := 0; i < int(gomaxprocs); i++ {
+		flushmcache(i)
+	}
+}
+
+// sysMemStat represents a global system statistic that is managed atomically.
+//
+// This type must structurally be a uint64 so that mstats aligns with MemStats.
+type sysMemStat uint64
+
+// load atomically reads the value of the stat.
+//
+// Must be nosplit as it is called in runtime initialization, e.g. newosproc0.
+//
+//go:nosplit
+func (s *sysMemStat) load() uint64 {
+	return atomic.Load64((*uint64)(s))
+}
+
+// add atomically adds the sysMemStat by n.
+//
+// Must be nosplit as it is called in runtime initialization, e.g. newosproc0.
+//
+//go:nosplit
+func (s *sysMemStat) add(n int64) {
+	val := atomic.Xadd64((*uint64)(s), n)
+	if (n > 0 && int64(val) < n) || (n < 0 && int64(val)+n < n) {
+		print("runtime: val=", val, " n=", n, "\n")
+		throw("sysMemStat overflow")
+	}
+}
+
+// heapStatsDelta contains deltas of various runtime memory statistics
+// that need to be updated together in order for them to be kept
+// consistent with one another.
+type heapStatsDelta struct {
+	// Memory stats.
+	committed       int64 // byte delta of memory committed
+	released        int64 // byte delta of released memory generated
+	inHeap          int64 // byte delta of memory placed in the heap
+	inStacks        int64 // byte delta of memory reserved for stacks
+	inWorkBufs      int64 // byte delta of memory reserved for work bufs
+	inPtrScalarBits int64 // byte delta of memory reserved for unrolled GC prog bits
+
+	// Allocator stats.
+	//
+	// These are all uint64 because they're cumulative, and could quickly wrap
+	// around otherwise.
+	tinyAllocCount  uint64                  // number of tiny allocations
+	largeAlloc      uint64                  // bytes allocated for large objects
+	largeAllocCount uint64                  // number of large object allocations
+	smallAllocCount [_NumSizeClasses]uint64 // number of allocs for small objects
+	largeFree       uint64                  // bytes freed for large objects (>maxSmallSize)
+	largeFreeCount  uint64                  // number of frees for large objects (>maxSmallSize)
+	smallFreeCount  [_NumSizeClasses]uint64 // number of frees for small objects (<=maxSmallSize)
+
+	// NOTE: This struct must be a multiple of 8 bytes in size because it
+	// is stored in an array. If it's not, atomic accesses to the above
+	// fields may be unaligned and fail on 32-bit platforms.
+}
+
+// merge adds in the deltas from b into a.
+func (a *heapStatsDelta) merge(b *heapStatsDelta) {
+	a.committed += b.committed
+	a.released += b.released
+	a.inHeap += b.inHeap
+	a.inStacks += b.inStacks
+	a.inWorkBufs += b.inWorkBufs
+	a.inPtrScalarBits += b.inPtrScalarBits
+
+	a.tinyAllocCount += b.tinyAllocCount
+	a.largeAlloc += b.largeAlloc
+	a.largeAllocCount += b.largeAllocCount
+	for i := range b.smallAllocCount {
+		a.smallAllocCount[i] += b.smallAllocCount[i]
+	}
+	a.largeFree += b.largeFree
+	a.largeFreeCount += b.largeFreeCount
+	for i := range b.smallFreeCount {
+		a.smallFreeCount[i] += b.smallFreeCount[i]
+	}
+}
+
+// consistentHeapStats represents a set of various memory statistics
+// whose updates must be viewed completely to get a consistent
+// state of the world.
+//
+// To write updates to memory stats use the acquire and release
+// methods. To obtain a consistent global snapshot of these statistics,
+// use read.
+type consistentHeapStats struct {
+	// stats is a ring buffer of heapStatsDelta values.
+	// Writers always atomically update the delta at index gen.
+	//
+	// Readers operate by rotating gen (0 -> 1 -> 2 -> 0 -> ...)
+	// and synchronizing with writers by observing each P's
+	// statsSeq field. If the reader observes a P not writing,
+	// it can be sure that it will pick up the new gen value the
+	// next time it writes.
+	//
+	// The reader then takes responsibility by clearing space
+	// in the ring buffer for the next reader to rotate gen to
+	// that space (i.e. it merges in values from index (gen-2) mod 3
+	// to index (gen-1) mod 3, then clears the former).
+	//
+	// Note that this means only one reader can be reading at a time.
+	// There is no way for readers to synchronize.
+	//
+	// This process is why we need a ring buffer of size 3 instead
+	// of 2: one is for the writers, one contains the most recent
+	// data, and the last one is clear so writers can begin writing
+	// to it the moment gen is updated.
+	stats [3]heapStatsDelta
+
+	// gen represents the current index into which writers
+	// are writing, and can take on the value of 0, 1, or 2.
+	// This value is updated atomically.
+	gen uint32
+
+	// noPLock is intended to provide mutual exclusion for updating
+	// stats when no P is available. It does not block other writers
+	// with a P, only other writers without a P and the reader. Because
+	// stats are usually updated when a P is available, contention on
+	// this lock should be minimal.
+	noPLock mutex
+}
+
+// acquire returns a heapStatsDelta to be updated. In effect,
+// it acquires the shard for writing. release must be called
+// as soon as the relevant deltas are updated.
+//
+// The returned heapStatsDelta must be updated atomically.
+//
+// The caller's P must not change between acquire and
+// release. This also means that the caller should not
+// acquire a P or release its P in between. A P also must
+// not acquire a given consistentHeapStats if it hasn't
+// yet released it.
+//
+// nosplit because a stack growth in this function could
+// lead to a stack allocation that could reenter the
+// function.
+//
+//go:nosplit
+func (m *consistentHeapStats) acquire() *heapStatsDelta {
+	if pp := getg().m.p.ptr(); pp != nil {
+		seq := atomic.Xadd(&pp.statsSeq, 1)
+		if seq%2 == 0 {
+			// Should have been incremented to odd.
+			print("runtime: seq=", seq, "\n")
+			throw("bad sequence number")
+		}
+	} else {
+		lock(&m.noPLock)
+	}
+	gen := atomic.Load(&m.gen) % 3
+	return &m.stats[gen]
+}
+
+// release indicates that the writer is done modifying
+// the delta. The value returned by the corresponding
+// acquire must no longer be accessed or modified after
+// release is called.
+//
+// The caller's P must not change between acquire and
+// release. This also means that the caller should not
+// acquire a P or release its P in between.
+//
+// nosplit because a stack growth in this function could
+// lead to a stack allocation that causes another acquire
+// before this operation has completed.
+//
+//go:nosplit
+func (m *consistentHeapStats) release() {
+	if pp := getg().m.p.ptr(); pp != nil {
+		seq := atomic.Xadd(&pp.statsSeq, 1)
+		if seq%2 != 0 {
+			// Should have been incremented to even.
+			print("runtime: seq=", seq, "\n")
+			throw("bad sequence number")
+		}
+	} else {
+		unlock(&m.noPLock)
+	}
+}
+
+// unsafeRead aggregates the delta for this shard into out.
+//
+// Unsafe because it does so without any synchronization. The
+// world must be stopped.
+func (m *consistentHeapStats) unsafeRead(out *heapStatsDelta) {
+	assertWorldStopped()
+
+	for i := range m.stats {
+		out.merge(&m.stats[i])
+	}
+}
+
+// unsafeClear clears the shard.
+//
+// Unsafe because the world must be stopped and values should
+// be donated elsewhere before clearing.
+func (m *consistentHeapStats) unsafeClear() {
+	assertWorldStopped()
+
+	for i := range m.stats {
+		m.stats[i] = heapStatsDelta{}
+	}
+}
+
+// read takes a globally consistent snapshot of m
+// and puts the aggregated value in out. Even though out is a
+// heapStatsDelta, the resulting values should be complete and
+// valid statistic values.
+//
+// Not safe to call concurrently. The world must be stopped
+// or metricsSema must be held.
+func (m *consistentHeapStats) read(out *heapStatsDelta) {
+	// Getting preempted after this point is not safe because
+	// we read allp. We need to make sure a STW can't happen
+	// so it doesn't change out from under us.
+	mp := acquirem()
+
+	// Get the current generation. We can be confident that this
+	// will not change since read is serialized and is the only
+	// one that modifies currGen.
+	currGen := atomic.Load(&m.gen)
+	prevGen := currGen - 1
+	if currGen == 0 {
+		prevGen = 2
+	}
+
+	// Prevent writers without a P from writing while we update gen.
+	lock(&m.noPLock)
+
+	// Rotate gen, effectively taking a snapshot of the state of
+	// these statistics at the point of the exchange by moving
+	// writers to the next set of deltas.
+	//
+	// This exchange is safe to do because we won't race
+	// with anyone else trying to update this value.
+	atomic.Xchg(&m.gen, (currGen+1)%3)
+
+	// Allow P-less writers to continue. They'll be writing to the
+	// next generation now.
+	unlock(&m.noPLock)
+
+	for _, p := range allp {
+		// Spin until there are no more writers.
+		for atomic.Load(&p.statsSeq)%2 != 0 {
+		}
+	}
+
+	// At this point we've observed that each sequence
+	// number is even, so any future writers will observe
+	// the new gen value. That means it's safe to read from
+	// the other deltas in the stats buffer.
+
+	// Perform our responsibilities and free up
+	// stats[prevGen] for the next time we want to take
+	// a snapshot.
+	m.stats[currGen].merge(&m.stats[prevGen])
+	m.stats[prevGen] = heapStatsDelta{}
+
+	// Finally, copy out the complete delta.
+	*out = m.stats[currGen]
+
+	releasem(mp)
+}
diff --git a/contrib/go/_std_1.19/src/runtime/mwbbuf.go b/contrib/go/_std_1.19/src/runtime/mwbbuf.go
new file mode 100644
index 0000000000..39ce0b46a9
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/mwbbuf.go
@@ -0,0 +1,290 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This implements the write barrier buffer. The write barrier itself
+// is gcWriteBarrier and is implemented in assembly.
+//
+// See mbarrier.go for algorithmic details on the write barrier. This
+// file deals only with the buffer.
+//
+// The write barrier has a fast path and a slow path. The fast path
+// simply enqueues to a per-P write barrier buffer. It's written in
+// assembly and doesn't clobber any general purpose registers, so it
+// doesn't have the usual overheads of a Go call.
+//
+// When the buffer fills up, the write barrier invokes the slow path
+// (wbBufFlush) to flush the buffer to the GC work queues. In this
+// path, since the compiler didn't spill registers, we spill *all*
+// registers and disallow any GC safe points that could observe the
+// stack frame (since we don't know the types of the spilled
+// registers).
+
+package runtime
+
+import (
+	"internal/goarch"
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+// testSmallBuf forces a small write barrier buffer to stress write
+// barrier flushing.
+const testSmallBuf = false
+
+// wbBuf is a per-P buffer of pointers queued by the write barrier.
+// This buffer is flushed to the GC workbufs when it fills up and on
+// various GC transitions.
+//
+// This is closely related to a "sequential store buffer" (SSB),
+// except that SSBs are usually used for maintaining remembered sets,
+// while this is used for marking.
+type wbBuf struct {
+	// next points to the next slot in buf. It must not be a
+	// pointer type because it can point past the end of buf and
+	// must be updated without write barriers.
+	//
+	// This is a pointer rather than an index to optimize the
+	// write barrier assembly.
+	next uintptr
+
+	// end points to just past the end of buf. It must not be a
+	// pointer type because it points past the end of buf and must
+	// be updated without write barriers.
+	end uintptr
+
+	// buf stores a series of pointers to execute write barriers
+	// on. This must be a multiple of wbBufEntryPointers because
+	// the write barrier only checks for overflow once per entry.
+	buf [wbBufEntryPointers * wbBufEntries]uintptr
+}
+
+const (
+	// wbBufEntries is the number of write barriers between
+	// flushes of the write barrier buffer.
+	//
+	// This trades latency for throughput amortization. Higher
+	// values amortize flushing overhead more, but increase the
+	// latency of flushing. Higher values also increase the cache
+	// footprint of the buffer.
+	//
+	// TODO: What is the latency cost of this? Tune this value.
+	wbBufEntries = 256
+
+	// wbBufEntryPointers is the number of pointers added to the
+	// buffer by each write barrier.
+	wbBufEntryPointers = 2
+)
+
+// reset empties b by resetting its next and end pointers.
+func (b *wbBuf) reset() {
+	start := uintptr(unsafe.Pointer(&b.buf[0]))
+	b.next = start
+	if writeBarrier.cgo {
+		// Effectively disable the buffer by forcing a flush
+		// on every barrier.
+		b.end = uintptr(unsafe.Pointer(&b.buf[wbBufEntryPointers]))
+	} else if testSmallBuf {
+		// For testing, allow two barriers in the buffer. If
+		// we only did one, then barriers of non-heap pointers
+		// would be no-ops. This lets us combine a buffered
+		// barrier with a flush at a later time.
+		b.end = uintptr(unsafe.Pointer(&b.buf[2*wbBufEntryPointers]))
+	} else {
+		b.end = start + uintptr(len(b.buf))*unsafe.Sizeof(b.buf[0])
+	}
+
+	if (b.end-b.next)%(wbBufEntryPointers*unsafe.Sizeof(b.buf[0])) != 0 {
+		throw("bad write barrier buffer bounds")
+	}
+}
+
+// discard resets b's next pointer, but not its end pointer.
+//
+// This must be nosplit because it's called by wbBufFlush.
+//
+//go:nosplit
+func (b *wbBuf) discard() {
+	b.next = uintptr(unsafe.Pointer(&b.buf[0]))
+}
+
+// empty reports whether b contains no pointers.
+func (b *wbBuf) empty() bool {
+	return b.next == uintptr(unsafe.Pointer(&b.buf[0]))
+}
+
+// putFast adds old and new to the write barrier buffer and returns
+// false if a flush is necessary. Callers should use this as:
+//
+//	buf := &getg().m.p.ptr().wbBuf
+//	if !buf.putFast(old, new) {
+//	    wbBufFlush(...)
+//	}
+//	... actual memory write ...
+//
+// The arguments to wbBufFlush depend on whether the caller is doing
+// its own cgo pointer checks. If it is, then this can be
+// wbBufFlush(nil, 0). Otherwise, it must pass the slot address and
+// new.
+//
+// The caller must ensure there are no preemption points during the
+// above sequence. There must be no preemption points while buf is in
+// use because it is a per-P resource. There must be no preemption
+// points between the buffer put and the write to memory because this
+// could allow a GC phase change, which could result in missed write
+// barriers.
+//
+// putFast must be nowritebarrierrec to because write barriers here would
+// corrupt the write barrier buffer. It (and everything it calls, if
+// it called anything) has to be nosplit to avoid scheduling on to a
+// different P and a different buffer.
+//
+//go:nowritebarrierrec
+//go:nosplit
+func (b *wbBuf) putFast(old, new uintptr) bool {
+	p := (*[2]uintptr)(unsafe.Pointer(b.next))
+	p[0] = old
+	p[1] = new
+	b.next += 2 * goarch.PtrSize
+	return b.next != b.end
+}
+
+// wbBufFlush flushes the current P's write barrier buffer to the GC
+// workbufs. It is passed the slot and value of the write barrier that
+// caused the flush so that it can implement cgocheck.
+//
+// This must not have write barriers because it is part of the write
+// barrier implementation.
+//
+// This and everything it calls must be nosplit because 1) the stack
+// contains untyped slots from gcWriteBarrier and 2) there must not be
+// a GC safe point between the write barrier test in the caller and
+// flushing the buffer.
+//
+// TODO: A "go:nosplitrec" annotation would be perfect for this.
+//
+//go:nowritebarrierrec
+//go:nosplit
+func wbBufFlush(dst *uintptr, src uintptr) {
+	// Note: Every possible return from this function must reset
+	// the buffer's next pointer to prevent buffer overflow.
+
+	// This *must not* modify its arguments because this
+	// function's argument slots do double duty in gcWriteBarrier
+	// as register spill slots. Currently, not modifying the
+	// arguments is sufficient to keep the spill slots unmodified
+	// (which seems unlikely to change since it costs little and
+	// helps with debugging).
+
+	if getg().m.dying > 0 {
+		// We're going down. Not much point in write barriers
+		// and this way we can allow write barriers in the
+		// panic path.
+		getg().m.p.ptr().wbBuf.discard()
+		return
+	}
+
+	if writeBarrier.cgo && dst != nil {
+		// This must be called from the stack that did the
+		// write. It's nosplit all the way down.
+		cgoCheckWriteBarrier(dst, src)
+		if !writeBarrier.needed {
+			// We were only called for cgocheck.
+			getg().m.p.ptr().wbBuf.discard()
+			return
+		}
+	}
+
+	// Switch to the system stack so we don't have to worry about
+	// the untyped stack slots or safe points.
+	systemstack(func() {
+		wbBufFlush1(getg().m.p.ptr())
+	})
+}
+
+// wbBufFlush1 flushes p's write barrier buffer to the GC work queue.
+//
+// This must not have write barriers because it is part of the write
+// barrier implementation, so this may lead to infinite loops or
+// buffer corruption.
+//
+// This must be non-preemptible because it uses the P's workbuf.
+//
+//go:nowritebarrierrec
+//go:systemstack
+func wbBufFlush1(_p_ *p) {
+	// Get the buffered pointers.
+	start := uintptr(unsafe.Pointer(&_p_.wbBuf.buf[0]))
+	n := (_p_.wbBuf.next - start) / unsafe.Sizeof(_p_.wbBuf.buf[0])
+	ptrs := _p_.wbBuf.buf[:n]
+
+	// Poison the buffer to make extra sure nothing is enqueued
+	// while we're processing the buffer.
+	_p_.wbBuf.next = 0
+
+	if useCheckmark {
+		// Slow path for checkmark mode.
+		for _, ptr := range ptrs {
+			shade(ptr)
+		}
+		_p_.wbBuf.reset()
+		return
+	}
+
+	// Mark all of the pointers in the buffer and record only the
+	// pointers we greyed. We use the buffer itself to temporarily
+	// record greyed pointers.
+	//
+	// TODO: Should scanobject/scanblock just stuff pointers into
+	// the wbBuf? Then this would become the sole greying path.
+	//
+	// TODO: We could avoid shading any of the "new" pointers in
+	// the buffer if the stack has been shaded, or even avoid
+	// putting them in the buffer at all (which would double its
+	// capacity). This is slightly complicated with the buffer; we
+	// could track whether any un-shaded goroutine has used the
+	// buffer, or just track globally whether there are any
+	// un-shaded stacks and flush after each stack scan.
+	gcw := &_p_.gcw
+	pos := 0
+	for _, ptr := range ptrs {
+		if ptr < minLegalPointer {
+			// nil pointers are very common, especially
+			// for the "old" values. Filter out these and
+			// other "obvious" non-heap pointers ASAP.
+			//
+			// TODO: Should we filter out nils in the fast
+			// path to reduce the rate of flushes?
+			continue
+		}
+		obj, span, objIndex := findObject(ptr, 0, 0)
+		if obj == 0 {
+			continue
+		}
+		// TODO: Consider making two passes where the first
+		// just prefetches the mark bits.
+		mbits := span.markBitsForIndex(objIndex)
+		if mbits.isMarked() {
+			continue
+		}
+		mbits.setMarked()
+
+		// Mark span.
+		arena, pageIdx, pageMask := pageIndexOf(span.base())
+		if arena.pageMarks[pageIdx]&pageMask == 0 {
+			atomic.Or8(&arena.pageMarks[pageIdx], pageMask)
+		}
+
+		if span.spanclass.noscan() {
+			gcw.bytesMarked += uint64(span.elemsize)
+			continue
+		}
+		ptrs[pos] = obj
+		pos++
+	}
+
+	// Enqueue the greyed objects.
+	gcw.putBatch(ptrs[:pos])
+
+	_p_.wbBuf.reset()
+}
diff --git a/contrib/go/_std_1.18/src/runtime/nbpipe_pipe.go b/contrib/go/_std_1.19/src/runtime/nbpipe_pipe.go
index 408e1ec410..408e1ec410 100644
--- a/contrib/go/_std_1.18/src/runtime/nbpipe_pipe.go
+++ b/contrib/go/_std_1.19/src/runtime/nbpipe_pipe.go
diff --git a/contrib/go/_std_1.19/src/runtime/nbpipe_pipe2.go b/contrib/go/_std_1.19/src/runtime/nbpipe_pipe2.go
new file mode 100644
index 0000000000..22d60b4a63
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/nbpipe_pipe2.go
@@ -0,0 +1,11 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build dragonfly || freebsd || linux || netbsd || openbsd || solaris
+
+package runtime
+
+func nonblockingPipe() (r, w int32, errno int32) {
+	return pipe2(_O_NONBLOCK | _O_CLOEXEC)
+}
diff --git a/contrib/go/_std_1.19/src/runtime/netpoll.go b/contrib/go/_std_1.19/src/runtime/netpoll.go
new file mode 100644
index 0000000000..ac6bc89530
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/netpoll.go
@@ -0,0 +1,656 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm) || windows
+
+package runtime
+
+import (
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+// Integrated network poller (platform-independent part).
+// A particular implementation (epoll/kqueue/port/AIX/Windows)
+// must define the following functions:
+//
+// func netpollinit()
+//     Initialize the poller. Only called once.
+//
+// func netpollopen(fd uintptr, pd *pollDesc) int32
+//     Arm edge-triggered notifications for fd. The pd argument is to pass
+//     back to netpollready when fd is ready. Return an errno value.
+//
+// func netpollclose(fd uintptr) int32
+//     Disable notifications for fd. Return an errno value.
+//
+// func netpoll(delta int64) gList
+//     Poll the network. If delta < 0, block indefinitely. If delta == 0,
+//     poll without blocking. If delta > 0, block for up to delta nanoseconds.
+//     Return a list of goroutines built by calling netpollready.
+//
+// func netpollBreak()
+//     Wake up the network poller, assumed to be blocked in netpoll.
+//
+// func netpollIsPollDescriptor(fd uintptr) bool
+//     Reports whether fd is a file descriptor used by the poller.
+
+// Error codes returned by runtime_pollReset and runtime_pollWait.
+// These must match the values in internal/poll/fd_poll_runtime.go.
+const (
+	pollNoError        = 0 // no error
+	pollErrClosing     = 1 // descriptor is closed
+	pollErrTimeout     = 2 // I/O timeout
+	pollErrNotPollable = 3 // general error polling descriptor
+)
+
+// pollDesc contains 2 binary semaphores, rg and wg, to park reader and writer
+// goroutines respectively. The semaphore can be in the following states:
+//
+//	pdReady - io readiness notification is pending;
+//	          a goroutine consumes the notification by changing the state to nil.
+//	pdWait - a goroutine prepares to park on the semaphore, but not yet parked;
+//	         the goroutine commits to park by changing the state to G pointer,
+//	         or, alternatively, concurrent io notification changes the state to pdReady,
+//	         or, alternatively, concurrent timeout/close changes the state to nil.
+//	G pointer - the goroutine is blocked on the semaphore;
+//	            io notification or timeout/close changes the state to pdReady or nil respectively
+//	            and unparks the goroutine.
+//	nil - none of the above.
+const (
+	pdReady uintptr = 1
+	pdWait  uintptr = 2
+)
+
+const pollBlockSize = 4 * 1024
+
+// Network poller descriptor.
+//
+// No heap pointers.
+//
+//go:notinheap
+type pollDesc struct {
+	link *pollDesc // in pollcache, protected by pollcache.lock
+	fd   uintptr   // constant for pollDesc usage lifetime
+
+	// atomicInfo holds bits from closing, rd, and wd,
+	// which are only ever written while holding the lock,
+	// summarized for use by netpollcheckerr,
+	// which cannot acquire the lock.
+	// After writing these fields under lock in a way that
+	// might change the summary, code must call publishInfo
+	// before releasing the lock.
+	// Code that changes fields and then calls netpollunblock
+	// (while still holding the lock) must call publishInfo
+	// before calling netpollunblock, because publishInfo is what
+	// stops netpollblock from blocking anew
+	// (by changing the result of netpollcheckerr).
+	// atomicInfo also holds the eventErr bit,
+	// recording whether a poll event on the fd got an error;
+	// atomicInfo is the only source of truth for that bit.
+	atomicInfo atomic.Uint32 // atomic pollInfo
+
+	// rg, wg are accessed atomically and hold g pointers.
+	// (Using atomic.Uintptr here is similar to using guintptr elsewhere.)
+	rg atomic.Uintptr // pdReady, pdWait, G waiting for read or nil
+	wg atomic.Uintptr // pdReady, pdWait, G waiting for write or nil
+
+	lock    mutex // protects the following fields
+	closing bool
+	user    uint32    // user settable cookie
+	rseq    uintptr   // protects from stale read timers
+	rt      timer     // read deadline timer (set if rt.f != nil)
+	rd      int64     // read deadline (a nanotime in the future, -1 when expired)
+	wseq    uintptr   // protects from stale write timers
+	wt      timer     // write deadline timer
+	wd      int64     // write deadline (a nanotime in the future, -1 when expired)
+	self    *pollDesc // storage for indirect interface. See (*pollDesc).makeArg.
+}
+
+// pollInfo is the bits needed by netpollcheckerr, stored atomically,
+// mostly duplicating state that is manipulated under lock in pollDesc.
+// The one exception is the pollEventErr bit, which is maintained only
+// in the pollInfo.
+type pollInfo uint32
+
+const (
+	pollClosing = 1 << iota
+	pollEventErr
+	pollExpiredReadDeadline
+	pollExpiredWriteDeadline
+)
+
+func (i pollInfo) closing() bool              { return i&pollClosing != 0 }
+func (i pollInfo) eventErr() bool             { return i&pollEventErr != 0 }
+func (i pollInfo) expiredReadDeadline() bool  { return i&pollExpiredReadDeadline != 0 }
+func (i pollInfo) expiredWriteDeadline() bool { return i&pollExpiredWriteDeadline != 0 }
+
+// info returns the pollInfo corresponding to pd.
+func (pd *pollDesc) info() pollInfo {
+	return pollInfo(pd.atomicInfo.Load())
+}
+
+// publishInfo updates pd.atomicInfo (returned by pd.info)
+// using the other values in pd.
+// It must be called while holding pd.lock,
+// and it must be called after changing anything
+// that might affect the info bits.
+// In practice this means after changing closing
+// or changing rd or wd from < 0 to >= 0.
+func (pd *pollDesc) publishInfo() {
+	var info uint32
+	if pd.closing {
+		info |= pollClosing
+	}
+	if pd.rd < 0 {
+		info |= pollExpiredReadDeadline
+	}
+	if pd.wd < 0 {
+		info |= pollExpiredWriteDeadline
+	}
+
+	// Set all of x except the pollEventErr bit.
+	x := pd.atomicInfo.Load()
+	for !pd.atomicInfo.CompareAndSwap(x, (x&pollEventErr)|info) {
+		x = pd.atomicInfo.Load()
+	}
+}
+
+// setEventErr sets the result of pd.info().eventErr() to b.
+func (pd *pollDesc) setEventErr(b bool) {
+	x := pd.atomicInfo.Load()
+	for (x&pollEventErr != 0) != b && !pd.atomicInfo.CompareAndSwap(x, x^pollEventErr) {
+		x = pd.atomicInfo.Load()
+	}
+}
+
+type pollCache struct {
+	lock  mutex
+	first *pollDesc
+	// PollDesc objects must be type-stable,
+	// because we can get ready notification from epoll/kqueue
+	// after the descriptor is closed/reused.
+	// Stale notifications are detected using seq variable,
+	// seq is incremented when deadlines are changed or descriptor is reused.
+}
+
+var (
+	netpollInitLock mutex
+	netpollInited   uint32
+
+	pollcache      pollCache
+	netpollWaiters uint32
+)
+
+//go:linkname poll_runtime_pollServerInit internal/poll.runtime_pollServerInit
+func poll_runtime_pollServerInit() {
+	netpollGenericInit()
+}
+
+func netpollGenericInit() {
+	if atomic.Load(&netpollInited) == 0 {
+		lockInit(&netpollInitLock, lockRankNetpollInit)
+		lock(&netpollInitLock)
+		if netpollInited == 0 {
+			netpollinit()
+			atomic.Store(&netpollInited, 1)
+		}
+		unlock(&netpollInitLock)
+	}
+}
+
+func netpollinited() bool {
+	return atomic.Load(&netpollInited) != 0
+}
+
+//go:linkname poll_runtime_isPollServerDescriptor internal/poll.runtime_isPollServerDescriptor
+
+// poll_runtime_isPollServerDescriptor reports whether fd is a
+// descriptor being used by netpoll.
+func poll_runtime_isPollServerDescriptor(fd uintptr) bool {
+	return netpollIsPollDescriptor(fd)
+}
+
+//go:linkname poll_runtime_pollOpen internal/poll.runtime_pollOpen
+func poll_runtime_pollOpen(fd uintptr) (*pollDesc, int) {
+	pd := pollcache.alloc()
+	lock(&pd.lock)
+	wg := pd.wg.Load()
+	if wg != 0 && wg != pdReady {
+		throw("runtime: blocked write on free polldesc")
+	}
+	rg := pd.rg.Load()
+	if rg != 0 && rg != pdReady {
+		throw("runtime: blocked read on free polldesc")
+	}
+	pd.fd = fd
+	pd.closing = false
+	pd.setEventErr(false)
+	pd.rseq++
+	pd.rg.Store(0)
+	pd.rd = 0
+	pd.wseq++
+	pd.wg.Store(0)
+	pd.wd = 0
+	pd.self = pd
+	pd.publishInfo()
+	unlock(&pd.lock)
+
+	errno := netpollopen(fd, pd)
+	if errno != 0 {
+		pollcache.free(pd)
+		return nil, int(errno)
+	}
+	return pd, 0
+}
+
+//go:linkname poll_runtime_pollClose internal/poll.runtime_pollClose
+func poll_runtime_pollClose(pd *pollDesc) {
+	if !pd.closing {
+		throw("runtime: close polldesc w/o unblock")
+	}
+	wg := pd.wg.Load()
+	if wg != 0 && wg != pdReady {
+		throw("runtime: blocked write on closing polldesc")
+	}
+	rg := pd.rg.Load()
+	if rg != 0 && rg != pdReady {
+		throw("runtime: blocked read on closing polldesc")
+	}
+	netpollclose(pd.fd)
+	pollcache.free(pd)
+}
+
+func (c *pollCache) free(pd *pollDesc) {
+	lock(&c.lock)
+	pd.link = c.first
+	c.first = pd
+	unlock(&c.lock)
+}
+
+// poll_runtime_pollReset, which is internal/poll.runtime_pollReset,
+// prepares a descriptor for polling in mode, which is 'r' or 'w'.
+// This returns an error code; the codes are defined above.
+//
+//go:linkname poll_runtime_pollReset internal/poll.runtime_pollReset
+func poll_runtime_pollReset(pd *pollDesc, mode int) int {
+	errcode := netpollcheckerr(pd, int32(mode))
+	if errcode != pollNoError {
+		return errcode
+	}
+	if mode == 'r' {
+		pd.rg.Store(0)
+	} else if mode == 'w' {
+		pd.wg.Store(0)
+	}
+	return pollNoError
+}
+
+// poll_runtime_pollWait, which is internal/poll.runtime_pollWait,
+// waits for a descriptor to be ready for reading or writing,
+// according to mode, which is 'r' or 'w'.
+// This returns an error code; the codes are defined above.
+//
+//go:linkname poll_runtime_pollWait internal/poll.runtime_pollWait
+func poll_runtime_pollWait(pd *pollDesc, mode int) int {
+	errcode := netpollcheckerr(pd, int32(mode))
+	if errcode != pollNoError {
+		return errcode
+	}
+	// As for now only Solaris, illumos, and AIX use level-triggered IO.
+	if GOOS == "solaris" || GOOS == "illumos" || GOOS == "aix" {
+		netpollarm(pd, mode)
+	}
+	for !netpollblock(pd, int32(mode), false) {
+		errcode = netpollcheckerr(pd, int32(mode))
+		if errcode != pollNoError {
+			return errcode
+		}
+		// Can happen if timeout has fired and unblocked us,
+		// but before we had a chance to run, timeout has been reset.
+		// Pretend it has not happened and retry.
+	}
+	return pollNoError
+}
+
+//go:linkname poll_runtime_pollWaitCanceled internal/poll.runtime_pollWaitCanceled
+func poll_runtime_pollWaitCanceled(pd *pollDesc, mode int) {
+	// This function is used only on windows after a failed attempt to cancel
+	// a pending async IO operation. Wait for ioready, ignore closing or timeouts.
+	for !netpollblock(pd, int32(mode), true) {
+	}
+}
+
+//go:linkname poll_runtime_pollSetDeadline internal/poll.runtime_pollSetDeadline
+func poll_runtime_pollSetDeadline(pd *pollDesc, d int64, mode int) {
+	lock(&pd.lock)
+	if pd.closing {
+		unlock(&pd.lock)
+		return
+	}
+	rd0, wd0 := pd.rd, pd.wd
+	combo0 := rd0 > 0 && rd0 == wd0
+	if d > 0 {
+		d += nanotime()
+		if d <= 0 {
+			// If the user has a deadline in the future, but the delay calculation
+			// overflows, then set the deadline to the maximum possible value.
+			d = 1<<63 - 1
+		}
+	}
+	if mode == 'r' || mode == 'r'+'w' {
+		pd.rd = d
+	}
+	if mode == 'w' || mode == 'r'+'w' {
+		pd.wd = d
+	}
+	pd.publishInfo()
+	combo := pd.rd > 0 && pd.rd == pd.wd
+	rtf := netpollReadDeadline
+	if combo {
+		rtf = netpollDeadline
+	}
+	if pd.rt.f == nil {
+		if pd.rd > 0 {
+			pd.rt.f = rtf
+			// Copy current seq into the timer arg.
+			// Timer func will check the seq against current descriptor seq,
+			// if they differ the descriptor was reused or timers were reset.
+			pd.rt.arg = pd.makeArg()
+			pd.rt.seq = pd.rseq
+			resettimer(&pd.rt, pd.rd)
+		}
+	} else if pd.rd != rd0 || combo != combo0 {
+		pd.rseq++ // invalidate current timers
+		if pd.rd > 0 {
+			modtimer(&pd.rt, pd.rd, 0, rtf, pd.makeArg(), pd.rseq)
+		} else {
+			deltimer(&pd.rt)
+			pd.rt.f = nil
+		}
+	}
+	if pd.wt.f == nil {
+		if pd.wd > 0 && !combo {
+			pd.wt.f = netpollWriteDeadline
+			pd.wt.arg = pd.makeArg()
+			pd.wt.seq = pd.wseq
+			resettimer(&pd.wt, pd.wd)
+		}
+	} else if pd.wd != wd0 || combo != combo0 {
+		pd.wseq++ // invalidate current timers
+		if pd.wd > 0 && !combo {
+			modtimer(&pd.wt, pd.wd, 0, netpollWriteDeadline, pd.makeArg(), pd.wseq)
+		} else {
+			deltimer(&pd.wt)
+			pd.wt.f = nil
+		}
+	}
+	// If we set the new deadline in the past, unblock currently pending IO if any.
+	// Note that pd.publishInfo has already been called, above, immediately after modifying rd and wd.
+	var rg, wg *g
+	if pd.rd < 0 {
+		rg = netpollunblock(pd, 'r', false)
+	}
+	if pd.wd < 0 {
+		wg = netpollunblock(pd, 'w', false)
+	}
+	unlock(&pd.lock)
+	if rg != nil {
+		netpollgoready(rg, 3)
+	}
+	if wg != nil {
+		netpollgoready(wg, 3)
+	}
+}
+
+//go:linkname poll_runtime_pollUnblock internal/poll.runtime_pollUnblock
+func poll_runtime_pollUnblock(pd *pollDesc) {
+	lock(&pd.lock)
+	if pd.closing {
+		throw("runtime: unblock on closing polldesc")
+	}
+	pd.closing = true
+	pd.rseq++
+	pd.wseq++
+	var rg, wg *g
+	pd.publishInfo()
+	rg = netpollunblock(pd, 'r', false)
+	wg = netpollunblock(pd, 'w', false)
+	if pd.rt.f != nil {
+		deltimer(&pd.rt)
+		pd.rt.f = nil
+	}
+	if pd.wt.f != nil {
+		deltimer(&pd.wt)
+		pd.wt.f = nil
+	}
+	unlock(&pd.lock)
+	if rg != nil {
+		netpollgoready(rg, 3)
+	}
+	if wg != nil {
+		netpollgoready(wg, 3)
+	}
+}
+
+// netpollready is called by the platform-specific netpoll function.
+// It declares that the fd associated with pd is ready for I/O.
+// The toRun argument is used to build a list of goroutines to return
+// from netpoll. The mode argument is 'r', 'w', or 'r'+'w' to indicate
+// whether the fd is ready for reading or writing or both.
+//
+// This may run while the world is stopped, so write barriers are not allowed.
+//
+//go:nowritebarrier
+func netpollready(toRun *gList, pd *pollDesc, mode int32) {
+	var rg, wg *g
+	if mode == 'r' || mode == 'r'+'w' {
+		rg = netpollunblock(pd, 'r', true)
+	}
+	if mode == 'w' || mode == 'r'+'w' {
+		wg = netpollunblock(pd, 'w', true)
+	}
+	if rg != nil {
+		toRun.push(rg)
+	}
+	if wg != nil {
+		toRun.push(wg)
+	}
+}
+
+func netpollcheckerr(pd *pollDesc, mode int32) int {
+	info := pd.info()
+	if info.closing() {
+		return pollErrClosing
+	}
+	if (mode == 'r' && info.expiredReadDeadline()) || (mode == 'w' && info.expiredWriteDeadline()) {
+		return pollErrTimeout
+	}
+	// Report an event scanning error only on a read event.
+	// An error on a write event will be captured in a subsequent
+	// write call that is able to report a more specific error.
+	if mode == 'r' && info.eventErr() {
+		return pollErrNotPollable
+	}
+	return pollNoError
+}
+
+func netpollblockcommit(gp *g, gpp unsafe.Pointer) bool {
+	r := atomic.Casuintptr((*uintptr)(gpp), pdWait, uintptr(unsafe.Pointer(gp)))
+	if r {
+		// Bump the count of goroutines waiting for the poller.
+		// The scheduler uses this to decide whether to block
+		// waiting for the poller if there is nothing else to do.
+		atomic.Xadd(&netpollWaiters, 1)
+	}
+	return r
+}
+
+func netpollgoready(gp *g, traceskip int) {
+	atomic.Xadd(&netpollWaiters, -1)
+	goready(gp, traceskip+1)
+}
+
+// returns true if IO is ready, or false if timedout or closed
+// waitio - wait only for completed IO, ignore errors
+// Concurrent calls to netpollblock in the same mode are forbidden, as pollDesc
+// can hold only a single waiting goroutine for each mode.
+func netpollblock(pd *pollDesc, mode int32, waitio bool) bool {
+	gpp := &pd.rg
+	if mode == 'w' {
+		gpp = &pd.wg
+	}
+
+	// set the gpp semaphore to pdWait
+	for {
+		// Consume notification if already ready.
+		if gpp.CompareAndSwap(pdReady, 0) {
+			return true
+		}
+		if gpp.CompareAndSwap(0, pdWait) {
+			break
+		}
+
+		// Double check that this isn't corrupt; otherwise we'd loop
+		// forever.
+		if v := gpp.Load(); v != pdReady && v != 0 {
+			throw("runtime: double wait")
+		}
+	}
+
+	// need to recheck error states after setting gpp to pdWait
+	// this is necessary because runtime_pollUnblock/runtime_pollSetDeadline/deadlineimpl
+	// do the opposite: store to closing/rd/wd, publishInfo, load of rg/wg
+	if waitio || netpollcheckerr(pd, mode) == pollNoError {
+		gopark(netpollblockcommit, unsafe.Pointer(gpp), waitReasonIOWait, traceEvGoBlockNet, 5)
+	}
+	// be careful to not lose concurrent pdReady notification
+	old := gpp.Swap(0)
+	if old > pdWait {
+		throw("runtime: corrupted polldesc")
+	}
+	return old == pdReady
+}
+
+func netpollunblock(pd *pollDesc, mode int32, ioready bool) *g {
+	gpp := &pd.rg
+	if mode == 'w' {
+		gpp = &pd.wg
+	}
+
+	for {
+		old := gpp.Load()
+		if old == pdReady {
+			return nil
+		}
+		if old == 0 && !ioready {
+			// Only set pdReady for ioready. runtime_pollWait
+			// will check for timeout/cancel before waiting.
+			return nil
+		}
+		var new uintptr
+		if ioready {
+			new = pdReady
+		}
+		if gpp.CompareAndSwap(old, new) {
+			if old == pdWait {
+				old = 0
+			}
+			return (*g)(unsafe.Pointer(old))
+		}
+	}
+}
+
+func netpolldeadlineimpl(pd *pollDesc, seq uintptr, read, write bool) {
+	lock(&pd.lock)
+	// Seq arg is seq when the timer was set.
+	// If it's stale, ignore the timer event.
+	currentSeq := pd.rseq
+	if !read {
+		currentSeq = pd.wseq
+	}
+	if seq != currentSeq {
+		// The descriptor was reused or timers were reset.
+		unlock(&pd.lock)
+		return
+	}
+	var rg *g
+	if read {
+		if pd.rd <= 0 || pd.rt.f == nil {
+			throw("runtime: inconsistent read deadline")
+		}
+		pd.rd = -1
+		pd.publishInfo()
+		rg = netpollunblock(pd, 'r', false)
+	}
+	var wg *g
+	if write {
+		if pd.wd <= 0 || pd.wt.f == nil && !read {
+			throw("runtime: inconsistent write deadline")
+		}
+		pd.wd = -1
+		pd.publishInfo()
+		wg = netpollunblock(pd, 'w', false)
+	}
+	unlock(&pd.lock)
+	if rg != nil {
+		netpollgoready(rg, 0)
+	}
+	if wg != nil {
+		netpollgoready(wg, 0)
+	}
+}
+
+func netpollDeadline(arg any, seq uintptr) {
+	netpolldeadlineimpl(arg.(*pollDesc), seq, true, true)
+}
+
+func netpollReadDeadline(arg any, seq uintptr) {
+	netpolldeadlineimpl(arg.(*pollDesc), seq, true, false)
+}
+
+func netpollWriteDeadline(arg any, seq uintptr) {
+	netpolldeadlineimpl(arg.(*pollDesc), seq, false, true)
+}
+
+func (c *pollCache) alloc() *pollDesc {
+	lock(&c.lock)
+	if c.first == nil {
+		const pdSize = unsafe.Sizeof(pollDesc{})
+		n := pollBlockSize / pdSize
+		if n == 0 {
+			n = 1
+		}
+		// Must be in non-GC memory because can be referenced
+		// only from epoll/kqueue internals.
+		mem := persistentalloc(n*pdSize, 0, &memstats.other_sys)
+		for i := uintptr(0); i < n; i++ {
+			pd := (*pollDesc)(add(mem, i*pdSize))
+			pd.link = c.first
+			c.first = pd
+		}
+	}
+	pd := c.first
+	c.first = pd.link
+	lockInit(&pd.lock, lockRankPollDesc)
+	unlock(&c.lock)
+	return pd
+}
+
+// makeArg converts pd to an interface{}.
+// makeArg does not do any allocation. Normally, such
+// a conversion requires an allocation because pointers to
+// go:notinheap types (which pollDesc is) must be stored
+// in interfaces indirectly. See issue 42076.
+func (pd *pollDesc) makeArg() (i any) {
+	x := (*eface)(unsafe.Pointer(&i))
+	x._type = pdType
+	x.data = unsafe.Pointer(&pd.self)
+	return
+}
+
+var (
+	pdEface any    = (*pollDesc)(nil)
+	pdType  *_type = efaceOf(&pdEface)._type
+)
diff --git a/contrib/go/_std_1.18/src/runtime/netpoll_epoll.go b/contrib/go/_std_1.19/src/runtime/netpoll_epoll.go
index b7d6199965..b7d6199965 100644
--- a/contrib/go/_std_1.18/src/runtime/netpoll_epoll.go
+++ b/contrib/go/_std_1.19/src/runtime/netpoll_epoll.go
diff --git a/contrib/go/_std_1.18/src/runtime/netpoll_kqueue.go b/contrib/go/_std_1.19/src/runtime/netpoll_kqueue.go
index 1694753b6f..1694753b6f 100644
--- a/contrib/go/_std_1.18/src/runtime/netpoll_kqueue.go
+++ b/contrib/go/_std_1.19/src/runtime/netpoll_kqueue.go
diff --git a/contrib/go/_std_1.19/src/runtime/os_darwin.go b/contrib/go/_std_1.19/src/runtime/os_darwin.go
new file mode 100644
index 0000000000..8562d7d906
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/os_darwin.go
@@ -0,0 +1,474 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"internal/abi"
+	"unsafe"
+)
+
+type mOS struct {
+	initialized bool
+	mutex       pthreadmutex
+	cond        pthreadcond
+	count       int
+}
+
+func unimplemented(name string) {
+	println(name, "not implemented")
+	*(*int)(unsafe.Pointer(uintptr(1231))) = 1231
+}
+
+//go:nosplit
+func semacreate(mp *m) {
+	if mp.initialized {
+		return
+	}
+	mp.initialized = true
+	if err := pthread_mutex_init(&mp.mutex, nil); err != 0 {
+		throw("pthread_mutex_init")
+	}
+	if err := pthread_cond_init(&mp.cond, nil); err != 0 {
+		throw("pthread_cond_init")
+	}
+}
+
+//go:nosplit
+func semasleep(ns int64) int32 {
+	var start int64
+	if ns >= 0 {
+		start = nanotime()
+	}
+	mp := getg().m
+	pthread_mutex_lock(&mp.mutex)
+	for {
+		if mp.count > 0 {
+			mp.count--
+			pthread_mutex_unlock(&mp.mutex)
+			return 0
+		}
+		if ns >= 0 {
+			spent := nanotime() - start
+			if spent >= ns {
+				pthread_mutex_unlock(&mp.mutex)
+				return -1
+			}
+			var t timespec
+			t.setNsec(ns - spent)
+			err := pthread_cond_timedwait_relative_np(&mp.cond, &mp.mutex, &t)
+			if err == _ETIMEDOUT {
+				pthread_mutex_unlock(&mp.mutex)
+				return -1
+			}
+		} else {
+			pthread_cond_wait(&mp.cond, &mp.mutex)
+		}
+	}
+}
+
+//go:nosplit
+func semawakeup(mp *m) {
+	pthread_mutex_lock(&mp.mutex)
+	mp.count++
+	if mp.count > 0 {
+		pthread_cond_signal(&mp.cond)
+	}
+	pthread_mutex_unlock(&mp.mutex)
+}
+
+// The read and write file descriptors used by the sigNote functions.
+var sigNoteRead, sigNoteWrite int32
+
+// sigNoteSetup initializes an async-signal-safe note.
+//
+// The current implementation of notes on Darwin is not async-signal-safe,
+// because the functions pthread_mutex_lock, pthread_cond_signal, and
+// pthread_mutex_unlock, called by semawakeup, are not async-signal-safe.
+// There is only one case where we need to wake up a note from a signal
+// handler: the sigsend function. The signal handler code does not require
+// all the features of notes: it does not need to do a timed wait.
+// This is a separate implementation of notes, based on a pipe, that does
+// not support timed waits but is async-signal-safe.
+func sigNoteSetup(*note) {
+	if sigNoteRead != 0 || sigNoteWrite != 0 {
+		throw("duplicate sigNoteSetup")
+	}
+	var errno int32
+	sigNoteRead, sigNoteWrite, errno = pipe()
+	if errno != 0 {
+		throw("pipe failed")
+	}
+	closeonexec(sigNoteRead)
+	closeonexec(sigNoteWrite)
+
+	// Make the write end of the pipe non-blocking, so that if the pipe
+	// buffer is somehow full we will not block in the signal handler.
+	// Leave the read end of the pipe blocking so that we will block
+	// in sigNoteSleep.
+	setNonblock(sigNoteWrite)
+}
+
+// sigNoteWakeup wakes up a thread sleeping on a note created by sigNoteSetup.
+func sigNoteWakeup(*note) {
+	var b byte
+	write(uintptr(sigNoteWrite), unsafe.Pointer(&b), 1)
+}
+
+// sigNoteSleep waits for a note created by sigNoteSetup to be woken.
+func sigNoteSleep(*note) {
+	for {
+		var b byte
+		entersyscallblock()
+		n := read(sigNoteRead, unsafe.Pointer(&b), 1)
+		exitsyscall()
+		if n != -_EINTR {
+			return
+		}
+	}
+}
+
+// BSD interface for threading.
+func osinit() {
+	// pthread_create delayed until end of goenvs so that we
+	// can look at the environment first.
+
+	ncpu = getncpu()
+	physPageSize = getPageSize()
+}
+
+func sysctlbynameInt32(name []byte) (int32, int32) {
+	out := int32(0)
+	nout := unsafe.Sizeof(out)
+	ret := sysctlbyname(&name[0], (*byte)(unsafe.Pointer(&out)), &nout, nil, 0)
+	return ret, out
+}
+
+//go:linkname internal_cpu_getsysctlbyname internal/cpu.getsysctlbyname
+func internal_cpu_getsysctlbyname(name []byte) (int32, int32) {
+	return sysctlbynameInt32(name)
+}
+
+const (
+	_CTL_HW      = 6
+	_HW_NCPU     = 3
+	_HW_PAGESIZE = 7
+)
+
+func getncpu() int32 {
+	// Use sysctl to fetch hw.ncpu.
+	mib := [2]uint32{_CTL_HW, _HW_NCPU}
+	out := uint32(0)
+	nout := unsafe.Sizeof(out)
+	ret := sysctl(&mib[0], 2, (*byte)(unsafe.Pointer(&out)), &nout, nil, 0)
+	if ret >= 0 && int32(out) > 0 {
+		return int32(out)
+	}
+	return 1
+}
+
+func getPageSize() uintptr {
+	// Use sysctl to fetch hw.pagesize.
+	mib := [2]uint32{_CTL_HW, _HW_PAGESIZE}
+	out := uint32(0)
+	nout := unsafe.Sizeof(out)
+	ret := sysctl(&mib[0], 2, (*byte)(unsafe.Pointer(&out)), &nout, nil, 0)
+	if ret >= 0 && int32(out) > 0 {
+		return uintptr(out)
+	}
+	return 0
+}
+
+var urandom_dev = []byte("/dev/urandom\x00")
+
+//go:nosplit
+func getRandomData(r []byte) {
+	fd := open(&urandom_dev[0], 0 /* O_RDONLY */, 0)
+	n := read(fd, unsafe.Pointer(&r[0]), int32(len(r)))
+	closefd(fd)
+	extendRandom(r, int(n))
+}
+
+func goenvs() {
+	goenvs_unix()
+}
+
+// May run with m.p==nil, so write barriers are not allowed.
+//
+//go:nowritebarrierrec
+func newosproc(mp *m) {
+	stk := unsafe.Pointer(mp.g0.stack.hi)
+	if false {
+		print("newosproc stk=", stk, " m=", mp, " g=", mp.g0, " id=", mp.id, " ostk=", &mp, "\n")
+	}
+
+	// Initialize an attribute object.
+	var attr pthreadattr
+	var err int32
+	err = pthread_attr_init(&attr)
+	if err != 0 {
+		write(2, unsafe.Pointer(&failthreadcreate[0]), int32(len(failthreadcreate)))
+		exit(1)
+	}
+
+	// Find out OS stack size for our own stack guard.
+	var stacksize uintptr
+	if pthread_attr_getstacksize(&attr, &stacksize) != 0 {
+		write(2, unsafe.Pointer(&failthreadcreate[0]), int32(len(failthreadcreate)))
+		exit(1)
+	}
+	mp.g0.stack.hi = stacksize // for mstart
+
+	// Tell the pthread library we won't join with this thread.
+	if pthread_attr_setdetachstate(&attr, _PTHREAD_CREATE_DETACHED) != 0 {
+		write(2, unsafe.Pointer(&failthreadcreate[0]), int32(len(failthreadcreate)))
+		exit(1)
+	}
+
+	// Finally, create the thread. It starts at mstart_stub, which does some low-level
+	// setup and then calls mstart.
+	var oset sigset
+	sigprocmask(_SIG_SETMASK, &sigset_all, &oset)
+	err = pthread_create(&attr, abi.FuncPCABI0(mstart_stub), unsafe.Pointer(mp))
+	sigprocmask(_SIG_SETMASK, &oset, nil)
+	if err != 0 {
+		write(2, unsafe.Pointer(&failthreadcreate[0]), int32(len(failthreadcreate)))
+		exit(1)
+	}
+}
+
+// glue code to call mstart from pthread_create.
+func mstart_stub()
+
+// newosproc0 is a version of newosproc that can be called before the runtime
+// is initialized.
+//
+// This function is not safe to use after initialization as it does not pass an M as fnarg.
+//
+//go:nosplit
+func newosproc0(stacksize uintptr, fn uintptr) {
+	// Initialize an attribute object.
+	var attr pthreadattr
+	var err int32
+	err = pthread_attr_init(&attr)
+	if err != 0 {
+		write(2, unsafe.Pointer(&failthreadcreate[0]), int32(len(failthreadcreate)))
+		exit(1)
+	}
+
+	// The caller passes in a suggested stack size,
+	// from when we allocated the stack and thread ourselves,
+	// without libpthread. Now that we're using libpthread,
+	// we use the OS default stack size instead of the suggestion.
+	// Find out that stack size for our own stack guard.
+	if pthread_attr_getstacksize(&attr, &stacksize) != 0 {
+		write(2, unsafe.Pointer(&failthreadcreate[0]), int32(len(failthreadcreate)))
+		exit(1)
+	}
+	g0.stack.hi = stacksize // for mstart
+	memstats.stacks_sys.add(int64(stacksize))
+
+	// Tell the pthread library we won't join with this thread.
+	if pthread_attr_setdetachstate(&attr, _PTHREAD_CREATE_DETACHED) != 0 {
+		write(2, unsafe.Pointer(&failthreadcreate[0]), int32(len(failthreadcreate)))
+		exit(1)
+	}
+
+	// Finally, create the thread. It starts at mstart_stub, which does some low-level
+	// setup and then calls mstart.
+	var oset sigset
+	sigprocmask(_SIG_SETMASK, &sigset_all, &oset)
+	err = pthread_create(&attr, fn, nil)
+	sigprocmask(_SIG_SETMASK, &oset, nil)
+	if err != 0 {
+		write(2, unsafe.Pointer(&failthreadcreate[0]), int32(len(failthreadcreate)))
+		exit(1)
+	}
+}
+
+var failallocatestack = []byte("runtime: failed to allocate stack for the new OS thread\n")
+var failthreadcreate = []byte("runtime: failed to create new OS thread\n")
+
+// Called to do synchronous initialization of Go code built with
+// -buildmode=c-archive or -buildmode=c-shared.
+// None of the Go runtime is initialized.
+//
+//go:nosplit
+//go:nowritebarrierrec
+func libpreinit() {
+	initsig(true)
+}
+
+// Called to initialize a new m (including the bootstrap m).
+// Called on the parent thread (main thread in case of bootstrap), can allocate memory.
+func mpreinit(mp *m) {
+	mp.gsignal = malg(32 * 1024) // OS X wants >= 8K
+	mp.gsignal.m = mp
+	if GOOS == "darwin" && GOARCH == "arm64" {
+		// mlock the signal stack to work around a kernel bug where it may
+		// SIGILL when the signal stack is not faulted in while a signal
+		// arrives. See issue 42774.
+		mlock(unsafe.Pointer(mp.gsignal.stack.hi-physPageSize), physPageSize)
+	}
+}
+
+// Called to initialize a new m (including the bootstrap m).
+// Called on the new thread, cannot allocate memory.
+func minit() {
+	// iOS does not support alternate signal stack.
+	// The signal handler handles it directly.
+	if !(GOOS == "ios" && GOARCH == "arm64") {
+		minitSignalStack()
+	}
+	minitSignalMask()
+	getg().m.procid = uint64(pthread_self())
+}
+
+// Called from dropm to undo the effect of an minit.
+//
+//go:nosplit
+func unminit() {
+	// iOS does not support alternate signal stack.
+	// See minit.
+	if !(GOOS == "ios" && GOARCH == "arm64") {
+		unminitSignals()
+	}
+}
+
+// Called from exitm, but not from drop, to undo the effect of thread-owned
+// resources in minit, semacreate, or elsewhere. Do not take locks after calling this.
+func mdestroy(mp *m) {
+}
+
+//go:nosplit
+func osyield_no_g() {
+	usleep_no_g(1)
+}
+
+//go:nosplit
+func osyield() {
+	usleep(1)
+}
+
+const (
+	_NSIG        = 32
+	_SI_USER     = 0 /* empirically true, but not what headers say */
+	_SIG_BLOCK   = 1
+	_SIG_UNBLOCK = 2
+	_SIG_SETMASK = 3
+	_SS_DISABLE  = 4
+)
+
+//extern SigTabTT runtime·sigtab[];
+
+type sigset uint32
+
+var sigset_all = ^sigset(0)
+
+//go:nosplit
+//go:nowritebarrierrec
+func setsig(i uint32, fn uintptr) {
+	var sa usigactiont
+	sa.sa_flags = _SA_SIGINFO | _SA_ONSTACK | _SA_RESTART
+	sa.sa_mask = ^uint32(0)
+	if fn == abi.FuncPCABIInternal(sighandler) { // abi.FuncPCABIInternal(sighandler) matches the callers in signal_unix.go
+		if iscgo {
+			fn = abi.FuncPCABI0(cgoSigtramp)
+		} else {
+			fn = abi.FuncPCABI0(sigtramp)
+		}
+	}
+	*(*uintptr)(unsafe.Pointer(&sa.__sigaction_u)) = fn
+	sigaction(i, &sa, nil)
+}
+
+// sigtramp is the callback from libc when a signal is received.
+// It is called with the C calling convention.
+func sigtramp()
+func cgoSigtramp()
+
+//go:nosplit
+//go:nowritebarrierrec
+func setsigstack(i uint32) {
+	var osa usigactiont
+	sigaction(i, nil, &osa)
+	handler := *(*uintptr)(unsafe.Pointer(&osa.__sigaction_u))
+	if osa.sa_flags&_SA_ONSTACK != 0 {
+		return
+	}
+	var sa usigactiont
+	*(*uintptr)(unsafe.Pointer(&sa.__sigaction_u)) = handler
+	sa.sa_mask = osa.sa_mask
+	sa.sa_flags = osa.sa_flags | _SA_ONSTACK
+	sigaction(i, &sa, nil)
+}
+
+//go:nosplit
+//go:nowritebarrierrec
+func getsig(i uint32) uintptr {
+	var sa usigactiont
+	sigaction(i, nil, &sa)
+	return *(*uintptr)(unsafe.Pointer(&sa.__sigaction_u))
+}
+
+// setSignaltstackSP sets the ss_sp field of a stackt.
+//
+//go:nosplit
+func setSignalstackSP(s *stackt, sp uintptr) {
+	*(*uintptr)(unsafe.Pointer(&s.ss_sp)) = sp
+}
+
+//go:nosplit
+//go:nowritebarrierrec
+func sigaddset(mask *sigset, i int) {
+	*mask |= 1 << (uint32(i) - 1)
+}
+
+func sigdelset(mask *sigset, i int) {
+	*mask &^= 1 << (uint32(i) - 1)
+}
+
+func setProcessCPUProfiler(hz int32) {
+	setProcessCPUProfilerTimer(hz)
+}
+
+func setThreadCPUProfiler(hz int32) {
+	setThreadCPUProfilerHz(hz)
+}
+
+//go:nosplit
+func validSIGPROF(mp *m, c *sigctxt) bool {
+	return true
+}
+
+//go:linkname executablePath os.executablePath
+var executablePath string
+
+func sysargs(argc int32, argv **byte) {
+	// skip over argv, envv and the first string will be the path
+	n := argc + 1
+	for argv_index(argv, n) != nil {
+		n++
+	}
+	executablePath = gostringnocopy(argv_index(argv, n+1))
+
+	// strip "executable_path=" prefix if available, it's added after OS X 10.11.
+	const prefix = "executable_path="
+	if len(executablePath) > len(prefix) && executablePath[:len(prefix)] == prefix {
+		executablePath = executablePath[len(prefix):]
+	}
+}
+
+func signalM(mp *m, sig int) {
+	pthread_kill(pthread(mp.procid), uint32(sig))
+}
+
+// sigPerThreadSyscall is only used on linux, so we assign a bogus signal
+// number.
+const sigPerThreadSyscall = 1 << 31
+
+//go:nosplit
+func runPerThreadSyscall() {
+	throw("runPerThreadSyscall only valid on linux")
+}
diff --git a/contrib/go/_std_1.19/src/runtime/os_linux.go b/contrib/go/_std_1.19/src/runtime/os_linux.go
new file mode 100644
index 0000000000..25aea6522d
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/os_linux.go
@@ -0,0 +1,888 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"internal/abi"
+	"internal/goarch"
+	"runtime/internal/atomic"
+	"runtime/internal/syscall"
+	"unsafe"
+)
+
+// sigPerThreadSyscall is the same signal (SIGSETXID) used by glibc for
+// per-thread syscalls on Linux. We use it for the same purpose in non-cgo
+// binaries.
+const sigPerThreadSyscall = _SIGRTMIN + 1
+
+type mOS struct {
+	// profileTimer holds the ID of the POSIX interval timer for profiling CPU
+	// usage on this thread.
+	//
+	// It is valid when the profileTimerValid field is non-zero. A thread
+	// creates and manages its own timer, and these fields are read and written
+	// only by this thread. But because some of the reads on profileTimerValid
+	// are in signal handling code, access to that field uses atomic operations.
+	profileTimer      int32
+	profileTimerValid uint32
+
+	// needPerThreadSyscall indicates that a per-thread syscall is required
+	// for doAllThreadsSyscall.
+	needPerThreadSyscall atomic.Uint8
+}
+
+//go:noescape
+func futex(addr unsafe.Pointer, op int32, val uint32, ts, addr2 unsafe.Pointer, val3 uint32) int32
+
+// Linux futex.
+//
+//	futexsleep(uint32 *addr, uint32 val)
+//	futexwakeup(uint32 *addr)
+//
+// Futexsleep atomically checks if *addr == val and if so, sleeps on addr.
+// Futexwakeup wakes up threads sleeping on addr.
+// Futexsleep is allowed to wake up spuriously.
+
+const (
+	_FUTEX_PRIVATE_FLAG = 128
+	_FUTEX_WAIT_PRIVATE = 0 | _FUTEX_PRIVATE_FLAG
+	_FUTEX_WAKE_PRIVATE = 1 | _FUTEX_PRIVATE_FLAG
+)
+
+// Atomically,
+//
+//	if(*addr == val) sleep
+//
+// Might be woken up spuriously; that's allowed.
+// Don't sleep longer than ns; ns < 0 means forever.
+//
+//go:nosplit
+func futexsleep(addr *uint32, val uint32, ns int64) {
+	// Some Linux kernels have a bug where futex of
+	// FUTEX_WAIT returns an internal error code
+	// as an errno. Libpthread ignores the return value
+	// here, and so can we: as it says a few lines up,
+	// spurious wakeups are allowed.
+	if ns < 0 {
+		futex(unsafe.Pointer(addr), _FUTEX_WAIT_PRIVATE, val, nil, nil, 0)
+		return
+	}
+
+	var ts timespec
+	ts.setNsec(ns)
+	futex(unsafe.Pointer(addr), _FUTEX_WAIT_PRIVATE, val, unsafe.Pointer(&ts), nil, 0)
+}
+
+// If any procs are sleeping on addr, wake up at most cnt.
+//
+//go:nosplit
+func futexwakeup(addr *uint32, cnt uint32) {
+	ret := futex(unsafe.Pointer(addr), _FUTEX_WAKE_PRIVATE, cnt, nil, nil, 0)
+	if ret >= 0 {
+		return
+	}
+
+	// I don't know that futex wakeup can return
+	// EAGAIN or EINTR, but if it does, it would be
+	// safe to loop and call futex again.
+	systemstack(func() {
+		print("futexwakeup addr=", addr, " returned ", ret, "\n")
+	})
+
+	*(*int32)(unsafe.Pointer(uintptr(0x1006))) = 0x1006
+}
+
+func getproccount() int32 {
+	// This buffer is huge (8 kB) but we are on the system stack
+	// and there should be plenty of space (64 kB).
+	// Also this is a leaf, so we're not holding up the memory for long.
+	// See golang.org/issue/11823.
+	// The suggested behavior here is to keep trying with ever-larger
+	// buffers, but we don't have a dynamic memory allocator at the
+	// moment, so that's a bit tricky and seems like overkill.
+	const maxCPUs = 64 * 1024
+	var buf [maxCPUs / 8]byte
+	r := sched_getaffinity(0, unsafe.Sizeof(buf), &buf[0])
+	if r < 0 {
+		return 1
+	}
+	n := int32(0)
+	for _, v := range buf[:r] {
+		for v != 0 {
+			n += int32(v & 1)
+			v >>= 1
+		}
+	}
+	if n == 0 {
+		n = 1
+	}
+	return n
+}
+
+// Clone, the Linux rfork.
+const (
+	_CLONE_VM             = 0x100
+	_CLONE_FS             = 0x200
+	_CLONE_FILES          = 0x400
+	_CLONE_SIGHAND        = 0x800
+	_CLONE_PTRACE         = 0x2000
+	_CLONE_VFORK          = 0x4000
+	_CLONE_PARENT         = 0x8000
+	_CLONE_THREAD         = 0x10000
+	_CLONE_NEWNS          = 0x20000
+	_CLONE_SYSVSEM        = 0x40000
+	_CLONE_SETTLS         = 0x80000
+	_CLONE_PARENT_SETTID  = 0x100000
+	_CLONE_CHILD_CLEARTID = 0x200000
+	_CLONE_UNTRACED       = 0x800000
+	_CLONE_CHILD_SETTID   = 0x1000000
+	_CLONE_STOPPED        = 0x2000000
+	_CLONE_NEWUTS         = 0x4000000
+	_CLONE_NEWIPC         = 0x8000000
+
+	// As of QEMU 2.8.0 (5ea2fc84d), user emulation requires all six of these
+	// flags to be set when creating a thread; attempts to share the other
+	// five but leave SYSVSEM unshared will fail with -EINVAL.
+	//
+	// In non-QEMU environments CLONE_SYSVSEM is inconsequential as we do not
+	// use System V semaphores.
+
+	cloneFlags = _CLONE_VM | /* share memory */
+		_CLONE_FS | /* share cwd, etc */
+		_CLONE_FILES | /* share fd table */
+		_CLONE_SIGHAND | /* share sig handler table */
+		_CLONE_SYSVSEM | /* share SysV semaphore undo lists (see issue #20763) */
+		_CLONE_THREAD /* revisit - okay for now */
+)
+
+//go:noescape
+func clone(flags int32, stk, mp, gp, fn unsafe.Pointer) int32
+
+// May run with m.p==nil, so write barriers are not allowed.
+//
+//go:nowritebarrier
+func newosproc(mp *m) {
+	stk := unsafe.Pointer(mp.g0.stack.hi)
+	/*
+	 * note: strace gets confused if we use CLONE_PTRACE here.
+	 */
+	if false {
+		print("newosproc stk=", stk, " m=", mp, " g=", mp.g0, " clone=", abi.FuncPCABI0(clone), " id=", mp.id, " ostk=", &mp, "\n")
+	}
+
+	// Disable signals during clone, so that the new thread starts
+	// with signals disabled. It will enable them in minit.
+	var oset sigset
+	sigprocmask(_SIG_SETMASK, &sigset_all, &oset)
+	ret := clone(cloneFlags, stk, unsafe.Pointer(mp), unsafe.Pointer(mp.g0), unsafe.Pointer(abi.FuncPCABI0(mstart)))
+	sigprocmask(_SIG_SETMASK, &oset, nil)
+
+	if ret < 0 {
+		print("runtime: failed to create new OS thread (have ", mcount(), " already; errno=", -ret, ")\n")
+		if ret == -_EAGAIN {
+			println("runtime: may need to increase max user processes (ulimit -u)")
+		}
+		throw("newosproc")
+	}
+}
+
+// Version of newosproc that doesn't require a valid G.
+//
+//go:nosplit
+func newosproc0(stacksize uintptr, fn unsafe.Pointer) {
+	stack := sysAlloc(stacksize, &memstats.stacks_sys)
+	if stack == nil {
+		write(2, unsafe.Pointer(&failallocatestack[0]), int32(len(failallocatestack)))
+		exit(1)
+	}
+	ret := clone(cloneFlags, unsafe.Pointer(uintptr(stack)+stacksize), nil, nil, fn)
+	if ret < 0 {
+		write(2, unsafe.Pointer(&failthreadcreate[0]), int32(len(failthreadcreate)))
+		exit(1)
+	}
+}
+
+var failallocatestack = []byte("runtime: failed to allocate stack for the new OS thread\n")
+var failthreadcreate = []byte("runtime: failed to create new OS thread\n")
+
+const (
+	_AT_NULL   = 0  // End of vector
+	_AT_PAGESZ = 6  // System physical page size
+	_AT_HWCAP  = 16 // hardware capability bit vector
+	_AT_RANDOM = 25 // introduced in 2.6.29
+	_AT_HWCAP2 = 26 // hardware capability bit vector 2
+)
+
+var procAuxv = []byte("/proc/self/auxv\x00")
+
+var addrspace_vec [1]byte
+
+func mincore(addr unsafe.Pointer, n uintptr, dst *byte) int32
+
+func sysargs(argc int32, argv **byte) {
+	n := argc + 1
+
+	// skip over argv, envp to get to auxv
+	for argv_index(argv, n) != nil {
+		n++
+	}
+
+	// skip NULL separator
+	n++
+
+	// now argv+n is auxv
+	auxv := (*[1 << 28]uintptr)(add(unsafe.Pointer(argv), uintptr(n)*goarch.PtrSize))
+	if sysauxv(auxv[:]) != 0 {
+		return
+	}
+	// In some situations we don't get a loader-provided
+	// auxv, such as when loaded as a library on Android.
+	// Fall back to /proc/self/auxv.
+	fd := open(&procAuxv[0], 0 /* O_RDONLY */, 0)
+	if fd < 0 {
+		// On Android, /proc/self/auxv might be unreadable (issue 9229), so we fallback to
+		// try using mincore to detect the physical page size.
+		// mincore should return EINVAL when address is not a multiple of system page size.
+		const size = 256 << 10 // size of memory region to allocate
+		p, err := mmap(nil, size, _PROT_READ|_PROT_WRITE, _MAP_ANON|_MAP_PRIVATE, -1, 0)
+		if err != 0 {
+			return
+		}
+		var n uintptr
+		for n = 4 << 10; n < size; n <<= 1 {
+			err := mincore(unsafe.Pointer(uintptr(p)+n), 1, &addrspace_vec[0])
+			if err == 0 {
+				physPageSize = n
+				break
+			}
+		}
+		if physPageSize == 0 {
+			physPageSize = size
+		}
+		munmap(p, size)
+		return
+	}
+	var buf [128]uintptr
+	n = read(fd, noescape(unsafe.Pointer(&buf[0])), int32(unsafe.Sizeof(buf)))
+	closefd(fd)
+	if n < 0 {
+		return
+	}
+	// Make sure buf is terminated, even if we didn't read
+	// the whole file.
+	buf[len(buf)-2] = _AT_NULL
+	sysauxv(buf[:])
+}
+
+// startupRandomData holds random bytes initialized at startup. These come from
+// the ELF AT_RANDOM auxiliary vector.
+var startupRandomData []byte
+
+func sysauxv(auxv []uintptr) int {
+	var i int
+	for ; auxv[i] != _AT_NULL; i += 2 {
+		tag, val := auxv[i], auxv[i+1]
+		switch tag {
+		case _AT_RANDOM:
+			// The kernel provides a pointer to 16-bytes
+			// worth of random data.
+			startupRandomData = (*[16]byte)(unsafe.Pointer(val))[:]
+
+		case _AT_PAGESZ:
+			physPageSize = val
+		}
+
+		archauxv(tag, val)
+		vdsoauxv(tag, val)
+	}
+	return i / 2
+}
+
+var sysTHPSizePath = []byte("/sys/kernel/mm/transparent_hugepage/hpage_pmd_size\x00")
+
+func getHugePageSize() uintptr {
+	var numbuf [20]byte
+	fd := open(&sysTHPSizePath[0], 0 /* O_RDONLY */, 0)
+	if fd < 0 {
+		return 0
+	}
+	ptr := noescape(unsafe.Pointer(&numbuf[0]))
+	n := read(fd, ptr, int32(len(numbuf)))
+	closefd(fd)
+	if n <= 0 {
+		return 0
+	}
+	n-- // remove trailing newline
+	v, ok := atoi(slicebytetostringtmp((*byte)(ptr), int(n)))
+	if !ok || v < 0 {
+		v = 0
+	}
+	if v&(v-1) != 0 {
+		// v is not a power of 2
+		return 0
+	}
+	return uintptr(v)
+}
+
+func osinit() {
+	ncpu = getproccount()
+	physHugePageSize = getHugePageSize()
+	if iscgo {
+		// #42494 glibc and musl reserve some signals for
+		// internal use and require they not be blocked by
+		// the rest of a normal C runtime. When the go runtime
+		// blocks...unblocks signals, temporarily, the blocked
+		// interval of time is generally very short. As such,
+		// these expectations of *libc code are mostly met by
+		// the combined go+cgo system of threads. However,
+		// when go causes a thread to exit, via a return from
+		// mstart(), the combined runtime can deadlock if
+		// these signals are blocked. Thus, don't block these
+		// signals when exiting threads.
+		// - glibc: SIGCANCEL (32), SIGSETXID (33)
+		// - musl: SIGTIMER (32), SIGCANCEL (33), SIGSYNCCALL (34)
+		sigdelset(&sigsetAllExiting, 32)
+		sigdelset(&sigsetAllExiting, 33)
+		sigdelset(&sigsetAllExiting, 34)
+	}
+	osArchInit()
+}
+
+var urandom_dev = []byte("/dev/urandom\x00")
+
+func getRandomData(r []byte) {
+	if startupRandomData != nil {
+		n := copy(r, startupRandomData)
+		extendRandom(r, n)
+		return
+	}
+	fd := open(&urandom_dev[0], 0 /* O_RDONLY */, 0)
+	n := read(fd, unsafe.Pointer(&r[0]), int32(len(r)))
+	closefd(fd)
+	extendRandom(r, int(n))
+}
+
+func goenvs() {
+	goenvs_unix()
+}
+
+// Called to do synchronous initialization of Go code built with
+// -buildmode=c-archive or -buildmode=c-shared.
+// None of the Go runtime is initialized.
+//
+//go:nosplit
+//go:nowritebarrierrec
+func libpreinit() {
+	initsig(true)
+}
+
+// Called to initialize a new m (including the bootstrap m).
+// Called on the parent thread (main thread in case of bootstrap), can allocate memory.
+func mpreinit(mp *m) {
+	mp.gsignal = malg(32 * 1024) // Linux wants >= 2K
+	mp.gsignal.m = mp
+}
+
+func gettid() uint32
+
+// Called to initialize a new m (including the bootstrap m).
+// Called on the new thread, cannot allocate memory.
+func minit() {
+	minitSignals()
+
+	// Cgo-created threads and the bootstrap m are missing a
+	// procid. We need this for asynchronous preemption and it's
+	// useful in debuggers.
+	getg().m.procid = uint64(gettid())
+}
+
+// Called from dropm to undo the effect of an minit.
+//
+//go:nosplit
+func unminit() {
+	unminitSignals()
+}
+
+// Called from exitm, but not from drop, to undo the effect of thread-owned
+// resources in minit, semacreate, or elsewhere. Do not take locks after calling this.
+func mdestroy(mp *m) {
+}
+
+//#ifdef GOARCH_386
+//#define sa_handler k_sa_handler
+//#endif
+
+func sigreturn()
+func sigtramp() // Called via C ABI
+func cgoSigtramp()
+
+//go:noescape
+func sigaltstack(new, old *stackt)
+
+//go:noescape
+func setitimer(mode int32, new, old *itimerval)
+
+//go:noescape
+func timer_create(clockid int32, sevp *sigevent, timerid *int32) int32
+
+//go:noescape
+func timer_settime(timerid int32, flags int32, new, old *itimerspec) int32
+
+//go:noescape
+func timer_delete(timerid int32) int32
+
+//go:noescape
+func rtsigprocmask(how int32, new, old *sigset, size int32)
+
+//go:nosplit
+//go:nowritebarrierrec
+func sigprocmask(how int32, new, old *sigset) {
+	rtsigprocmask(how, new, old, int32(unsafe.Sizeof(*new)))
+}
+
+func raise(sig uint32)
+func raiseproc(sig uint32)
+
+//go:noescape
+func sched_getaffinity(pid, len uintptr, buf *byte) int32
+func osyield()
+
+//go:nosplit
+func osyield_no_g() {
+	osyield()
+}
+
+func pipe2(flags int32) (r, w int32, errno int32)
+
+const (
+	_si_max_size    = 128
+	_sigev_max_size = 64
+)
+
+//go:nosplit
+//go:nowritebarrierrec
+func setsig(i uint32, fn uintptr) {
+	var sa sigactiont
+	sa.sa_flags = _SA_SIGINFO | _SA_ONSTACK | _SA_RESTORER | _SA_RESTART
+	sigfillset(&sa.sa_mask)
+	// Although Linux manpage says "sa_restorer element is obsolete and
+	// should not be used". x86_64 kernel requires it. Only use it on
+	// x86.
+	if GOARCH == "386" || GOARCH == "amd64" {
+		sa.sa_restorer = abi.FuncPCABI0(sigreturn)
+	}
+	if fn == abi.FuncPCABIInternal(sighandler) { // abi.FuncPCABIInternal(sighandler) matches the callers in signal_unix.go
+		if iscgo {
+			fn = abi.FuncPCABI0(cgoSigtramp)
+		} else {
+			fn = abi.FuncPCABI0(sigtramp)
+		}
+	}
+	sa.sa_handler = fn
+	sigaction(i, &sa, nil)
+}
+
+//go:nosplit
+//go:nowritebarrierrec
+func setsigstack(i uint32) {
+	var sa sigactiont
+	sigaction(i, nil, &sa)
+	if sa.sa_flags&_SA_ONSTACK != 0 {
+		return
+	}
+	sa.sa_flags |= _SA_ONSTACK
+	sigaction(i, &sa, nil)
+}
+
+//go:nosplit
+//go:nowritebarrierrec
+func getsig(i uint32) uintptr {
+	var sa sigactiont
+	sigaction(i, nil, &sa)
+	return sa.sa_handler
+}
+
+// setSignaltstackSP sets the ss_sp field of a stackt.
+//
+//go:nosplit
+func setSignalstackSP(s *stackt, sp uintptr) {
+	*(*uintptr)(unsafe.Pointer(&s.ss_sp)) = sp
+}
+
+//go:nosplit
+func (c *sigctxt) fixsigcode(sig uint32) {
+}
+
+// sysSigaction calls the rt_sigaction system call.
+//
+//go:nosplit
+func sysSigaction(sig uint32, new, old *sigactiont) {
+	if rt_sigaction(uintptr(sig), new, old, unsafe.Sizeof(sigactiont{}.sa_mask)) != 0 {
+		// Workaround for bugs in QEMU user mode emulation.
+		//
+		// QEMU turns calls to the sigaction system call into
+		// calls to the C library sigaction call; the C
+		// library call rejects attempts to call sigaction for
+		// SIGCANCEL (32) or SIGSETXID (33).
+		//
+		// QEMU rejects calling sigaction on SIGRTMAX (64).
+		//
+		// Just ignore the error in these case. There isn't
+		// anything we can do about it anyhow.
+		if sig != 32 && sig != 33 && sig != 64 {
+			// Use system stack to avoid split stack overflow on ppc64/ppc64le.
+			systemstack(func() {
+				throw("sigaction failed")
+			})
+		}
+	}
+}
+
+// rt_sigaction is implemented in assembly.
+//
+//go:noescape
+func rt_sigaction(sig uintptr, new, old *sigactiont, size uintptr) int32
+
+func getpid() int
+func tgkill(tgid, tid, sig int)
+
+// signalM sends a signal to mp.
+func signalM(mp *m, sig int) {
+	tgkill(getpid(), int(mp.procid), sig)
+}
+
+// go118UseTimerCreateProfiler enables the per-thread CPU profiler.
+const go118UseTimerCreateProfiler = true
+
+// validSIGPROF compares this signal delivery's code against the signal sources
+// that the profiler uses, returning whether the delivery should be processed.
+// To be processed, a signal delivery from a known profiling mechanism should
+// correspond to the best profiling mechanism available to this thread. Signals
+// from other sources are always considered valid.
+//
+//go:nosplit
+func validSIGPROF(mp *m, c *sigctxt) bool {
+	code := int32(c.sigcode())
+	setitimer := code == _SI_KERNEL
+	timer_create := code == _SI_TIMER
+
+	if !(setitimer || timer_create) {
+		// The signal doesn't correspond to a profiling mechanism that the
+		// runtime enables itself. There's no reason to process it, but there's
+		// no reason to ignore it either.
+		return true
+	}
+
+	if mp == nil {
+		// Since we don't have an M, we can't check if there's an active
+		// per-thread timer for this thread. We don't know how long this thread
+		// has been around, and if it happened to interact with the Go scheduler
+		// at a time when profiling was active (causing it to have a per-thread
+		// timer). But it may have never interacted with the Go scheduler, or
+		// never while profiling was active. To avoid double-counting, process
+		// only signals from setitimer.
+		//
+		// When a custom cgo traceback function has been registered (on
+		// platforms that support runtime.SetCgoTraceback), SIGPROF signals
+		// delivered to a thread that cannot find a matching M do this check in
+		// the assembly implementations of runtime.cgoSigtramp.
+		return setitimer
+	}
+
+	// Having an M means the thread interacts with the Go scheduler, and we can
+	// check whether there's an active per-thread timer for this thread.
+	if atomic.Load(&mp.profileTimerValid) != 0 {
+		// If this M has its own per-thread CPU profiling interval timer, we
+		// should track the SIGPROF signals that come from that timer (for
+		// accurate reporting of its CPU usage; see issue 35057) and ignore any
+		// that it gets from the process-wide setitimer (to not over-count its
+		// CPU consumption).
+		return timer_create
+	}
+
+	// No active per-thread timer means the only valid profiler is setitimer.
+	return setitimer
+}
+
+func setProcessCPUProfiler(hz int32) {
+	setProcessCPUProfilerTimer(hz)
+}
+
+func setThreadCPUProfiler(hz int32) {
+	mp := getg().m
+	mp.profilehz = hz
+
+	if !go118UseTimerCreateProfiler {
+		return
+	}
+
+	// destroy any active timer
+	if atomic.Load(&mp.profileTimerValid) != 0 {
+		timerid := mp.profileTimer
+		atomic.Store(&mp.profileTimerValid, 0)
+		mp.profileTimer = 0
+
+		ret := timer_delete(timerid)
+		if ret != 0 {
+			print("runtime: failed to disable profiling timer; timer_delete(", timerid, ") errno=", -ret, "\n")
+			throw("timer_delete")
+		}
+	}
+
+	if hz == 0 {
+		// If the goal was to disable profiling for this thread, then the job's done.
+		return
+	}
+
+	// The period of the timer should be 1/Hz. For every "1/Hz" of additional
+	// work, the user should expect one additional sample in the profile.
+	//
+	// But to scale down to very small amounts of application work, to observe
+	// even CPU usage of "one tenth" of the requested period, set the initial
+	// timing delay in a different way: So that "one tenth" of a period of CPU
+	// spend shows up as a 10% chance of one sample (for an expected value of
+	// 0.1 samples), and so that "two and six tenths" periods of CPU spend show
+	// up as a 60% chance of 3 samples and a 40% chance of 2 samples (for an
+	// expected value of 2.6). Set the initial delay to a value in the unifom
+	// random distribution between 0 and the desired period. And because "0"
+	// means "disable timer", add 1 so the half-open interval [0,period) turns
+	// into (0,period].
+	//
+	// Otherwise, this would show up as a bias away from short-lived threads and
+	// from threads that are only occasionally active: for example, when the
+	// garbage collector runs on a mostly-idle system, the additional threads it
+	// activates may do a couple milliseconds of GC-related work and nothing
+	// else in the few seconds that the profiler observes.
+	spec := new(itimerspec)
+	spec.it_value.setNsec(1 + int64(fastrandn(uint32(1e9/hz))))
+	spec.it_interval.setNsec(1e9 / int64(hz))
+
+	var timerid int32
+	var sevp sigevent
+	sevp.notify = _SIGEV_THREAD_ID
+	sevp.signo = _SIGPROF
+	sevp.sigev_notify_thread_id = int32(mp.procid)
+	ret := timer_create(_CLOCK_THREAD_CPUTIME_ID, &sevp, &timerid)
+	if ret != 0 {
+		// If we cannot create a timer for this M, leave profileTimerValid false
+		// to fall back to the process-wide setitimer profiler.
+		return
+	}
+
+	ret = timer_settime(timerid, 0, spec, nil)
+	if ret != 0 {
+		print("runtime: failed to configure profiling timer; timer_settime(", timerid,
+			", 0, {interval: {",
+			spec.it_interval.tv_sec, "s + ", spec.it_interval.tv_nsec, "ns} value: {",
+			spec.it_value.tv_sec, "s + ", spec.it_value.tv_nsec, "ns}}, nil) errno=", -ret, "\n")
+		throw("timer_settime")
+	}
+
+	mp.profileTimer = timerid
+	atomic.Store(&mp.profileTimerValid, 1)
+}
+
+// perThreadSyscallArgs contains the system call number, arguments, and
+// expected return values for a system call to be executed on all threads.
+type perThreadSyscallArgs struct {
+	trap uintptr
+	a1   uintptr
+	a2   uintptr
+	a3   uintptr
+	a4   uintptr
+	a5   uintptr
+	a6   uintptr
+	r1   uintptr
+	r2   uintptr
+}
+
+// perThreadSyscall is the system call to execute for the ongoing
+// doAllThreadsSyscall.
+//
+// perThreadSyscall may only be written while mp.needPerThreadSyscall == 0 on
+// all Ms.
+var perThreadSyscall perThreadSyscallArgs
+
+// syscall_runtime_doAllThreadsSyscall and executes a specified system call on
+// all Ms.
+//
+// The system call is expected to succeed and return the same value on every
+// thread. If any threads do not match, the runtime throws.
+//
+//go:linkname syscall_runtime_doAllThreadsSyscall syscall.runtime_doAllThreadsSyscall
+//go:uintptrescapes
+func syscall_runtime_doAllThreadsSyscall(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr) {
+	if iscgo {
+		// In cgo, we are not aware of threads created in C, so this approach will not work.
+		panic("doAllThreadsSyscall not supported with cgo enabled")
+	}
+
+	// STW to guarantee that user goroutines see an atomic change to thread
+	// state. Without STW, goroutines could migrate Ms while change is in
+	// progress and e.g., see state old -> new -> old -> new.
+	//
+	// N.B. Internally, this function does not depend on STW to
+	// successfully change every thread. It is only needed for user
+	// expectations, per above.
+	stopTheWorld("doAllThreadsSyscall")
+
+	// This function depends on several properties:
+	//
+	// 1. All OS threads that already exist are associated with an M in
+	//    allm. i.e., we won't miss any pre-existing threads.
+	// 2. All Ms listed in allm will eventually have an OS thread exist.
+	//    i.e., they will set procid and be able to receive signals.
+	// 3. OS threads created after we read allm will clone from a thread
+	//    that has executed the system call. i.e., they inherit the
+	//    modified state.
+	//
+	// We achieve these through different mechanisms:
+	//
+	// 1. Addition of new Ms to allm in allocm happens before clone of its
+	//    OS thread later in newm.
+	// 2. newm does acquirem to avoid being preempted, ensuring that new Ms
+	//    created in allocm will eventually reach OS thread clone later in
+	//    newm.
+	// 3. We take allocmLock for write here to prevent allocation of new Ms
+	//    while this function runs. Per (1), this prevents clone of OS
+	//    threads that are not yet in allm.
+	allocmLock.lock()
+
+	// Disable preemption, preventing us from changing Ms, as we handle
+	// this M specially.
+	//
+	// N.B. STW and lock() above do this as well, this is added for extra
+	// clarity.
+	acquirem()
+
+	// N.B. allocmLock also prevents concurrent execution of this function,
+	// serializing use of perThreadSyscall, mp.needPerThreadSyscall, and
+	// ensuring all threads execute system calls from multiple calls in the
+	// same order.
+
+	r1, r2, errno := syscall.Syscall6(trap, a1, a2, a3, a4, a5, a6)
+	if GOARCH == "ppc64" || GOARCH == "ppc64le" {
+		// TODO(https://go.dev/issue/51192 ): ppc64 doesn't use r2.
+		r2 = 0
+	}
+	if errno != 0 {
+		releasem(getg().m)
+		allocmLock.unlock()
+		startTheWorld()
+		return r1, r2, errno
+	}
+
+	perThreadSyscall = perThreadSyscallArgs{
+		trap: trap,
+		a1:   a1,
+		a2:   a2,
+		a3:   a3,
+		a4:   a4,
+		a5:   a5,
+		a6:   a6,
+		r1:   r1,
+		r2:   r2,
+	}
+
+	// Wait for all threads to start.
+	//
+	// As described above, some Ms have been added to allm prior to
+	// allocmLock, but not yet completed OS clone and set procid.
+	//
+	// At minimum we must wait for a thread to set procid before we can
+	// send it a signal.
+	//
+	// We take this one step further and wait for all threads to start
+	// before sending any signals. This prevents system calls from getting
+	// applied twice: once in the parent and once in the child, like so:
+	//
+	//          A                     B                  C
+	//                         add C to allm
+	// doAllThreadsSyscall
+	//   allocmLock.lock()
+	//   signal B
+	//                         <receive signal>
+	//                         execute syscall
+	//                         <signal return>
+	//                         clone C
+	//                                             <thread start>
+	//                                             set procid
+	//   signal C
+	//                                             <receive signal>
+	//                                             execute syscall
+	//                                             <signal return>
+	//
+	// In this case, thread C inherited the syscall-modified state from
+	// thread B and did not need to execute the syscall, but did anyway
+	// because doAllThreadsSyscall could not be sure whether it was
+	// required.
+	//
+	// Some system calls may not be idempotent, so we ensure each thread
+	// executes the system call exactly once.
+	for mp := allm; mp != nil; mp = mp.alllink {
+		for atomic.Load64(&mp.procid) == 0 {
+			// Thread is starting.
+			osyield()
+		}
+	}
+
+	// Signal every other thread, where they will execute perThreadSyscall
+	// from the signal handler.
+	gp := getg()
+	tid := gp.m.procid
+	for mp := allm; mp != nil; mp = mp.alllink {
+		if atomic.Load64(&mp.procid) == tid {
+			// Our thread already performed the syscall.
+			continue
+		}
+		mp.needPerThreadSyscall.Store(1)
+		signalM(mp, sigPerThreadSyscall)
+	}
+
+	// Wait for all threads to complete.
+	for mp := allm; mp != nil; mp = mp.alllink {
+		if mp.procid == tid {
+			continue
+		}
+		for mp.needPerThreadSyscall.Load() != 0 {
+			osyield()
+		}
+	}
+
+	perThreadSyscall = perThreadSyscallArgs{}
+
+	releasem(getg().m)
+	allocmLock.unlock()
+	startTheWorld()
+
+	return r1, r2, errno
+}
+
+// runPerThreadSyscall runs perThreadSyscall for this M if required.
+//
+// This function throws if the system call returns with anything other than the
+// expected values.
+//
+//go:nosplit
+func runPerThreadSyscall() {
+	gp := getg()
+	if gp.m.needPerThreadSyscall.Load() == 0 {
+		return
+	}
+
+	args := perThreadSyscall
+	r1, r2, errno := syscall.Syscall6(args.trap, args.a1, args.a2, args.a3, args.a4, args.a5, args.a6)
+	if GOARCH == "ppc64" || GOARCH == "ppc64le" {
+		// TODO(https://go.dev/issue/51192 ): ppc64 doesn't use r2.
+		r2 = 0
+	}
+	if errno != 0 || r1 != args.r1 || r2 != args.r2 {
+		print("trap:", args.trap, ", a123456=[", args.a1, ",", args.a2, ",", args.a3, ",", args.a4, ",", args.a5, ",", args.a6, "]\n")
+		print("results: got {r1=", r1, ",r2=", r2, ",errno=", errno, "}, want {r1=", args.r1, ",r2=", args.r2, ",errno=0\n")
+		fatal("AllThreadsSyscall6 results differ between threads; runtime corrupted")
+	}
+
+	gp.m.needPerThreadSyscall.Store(0)
+}
diff --git a/contrib/go/_std_1.18/src/runtime/os_linux_generic.go b/contrib/go/_std_1.19/src/runtime/os_linux_generic.go
index bed9e66e15..bed9e66e15 100644
--- a/contrib/go/_std_1.18/src/runtime/os_linux_generic.go
+++ b/contrib/go/_std_1.19/src/runtime/os_linux_generic.go
diff --git a/contrib/go/_std_1.19/src/runtime/os_linux_noauxv.go b/contrib/go/_std_1.19/src/runtime/os_linux_noauxv.go
new file mode 100644
index 0000000000..ff377277aa
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/os_linux_noauxv.go
@@ -0,0 +1,10 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build linux && !arm && !arm64 && !loong64 && !mips && !mipsle && !mips64 && !mips64le && !s390x && !ppc64 && !ppc64le
+
+package runtime
+
+func archauxv(tag, val uintptr) {
+}
diff --git a/contrib/go/_std_1.18/src/runtime/os_linux_x86.go b/contrib/go/_std_1.19/src/runtime/os_linux_x86.go
index c88f61fa2e..c88f61fa2e 100644
--- a/contrib/go/_std_1.18/src/runtime/os_linux_x86.go
+++ b/contrib/go/_std_1.19/src/runtime/os_linux_x86.go
diff --git a/contrib/go/_std_1.18/src/runtime/os_nonopenbsd.go b/contrib/go/_std_1.19/src/runtime/os_nonopenbsd.go
index a5775961e8..a5775961e8 100644
--- a/contrib/go/_std_1.18/src/runtime/os_nonopenbsd.go
+++ b/contrib/go/_std_1.19/src/runtime/os_nonopenbsd.go
diff --git a/contrib/go/_std_1.19/src/runtime/panic.go b/contrib/go/_std_1.19/src/runtime/panic.go
new file mode 100644
index 0000000000..121f2022a4
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/panic.go
@@ -0,0 +1,1370 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"internal/goarch"
+	"runtime/internal/atomic"
+	"runtime/internal/sys"
+	"unsafe"
+)
+
+// throwType indicates the current type of ongoing throw, which affects the
+// amount of detail printed to stderr. Higher values include more detail.
+type throwType uint32
+
+const (
+	// throwTypeNone means that we are not throwing.
+	throwTypeNone throwType = iota
+
+	// throwTypeUser is a throw due to a problem with the application.
+	//
+	// These throws do not include runtime frames, system goroutines, or
+	// frame metadata.
+	throwTypeUser
+
+	// throwTypeRuntime is a throw due to a problem with Go itself.
+	//
+	// These throws include as much information as possible to aid in
+	// debugging the runtime, including runtime frames, system goroutines,
+	// and frame metadata.
+	throwTypeRuntime
+)
+
+// We have two different ways of doing defers. The older way involves creating a
+// defer record at the time that a defer statement is executing and adding it to a
+// defer chain. This chain is inspected by the deferreturn call at all function
+// exits in order to run the appropriate defer calls. A cheaper way (which we call
+// open-coded defers) is used for functions in which no defer statements occur in
+// loops. In that case, we simply store the defer function/arg information into
+// specific stack slots at the point of each defer statement, as well as setting a
+// bit in a bitmask. At each function exit, we add inline code to directly make
+// the appropriate defer calls based on the bitmask and fn/arg information stored
+// on the stack. During panic/Goexit processing, the appropriate defer calls are
+// made using extra funcdata info that indicates the exact stack slots that
+// contain the bitmask and defer fn/args.
+
+// Check to make sure we can really generate a panic. If the panic
+// was generated from the runtime, or from inside malloc, then convert
+// to a throw of msg.
+// pc should be the program counter of the compiler-generated code that
+// triggered this panic.
+func panicCheck1(pc uintptr, msg string) {
+	if goarch.IsWasm == 0 && hasPrefix(funcname(findfunc(pc)), "runtime.") {
+		// Note: wasm can't tail call, so we can't get the original caller's pc.
+		throw(msg)
+	}
+	// TODO: is this redundant? How could we be in malloc
+	// but not in the runtime? runtime/internal/*, maybe?
+	gp := getg()
+	if gp != nil && gp.m != nil && gp.m.mallocing != 0 {
+		throw(msg)
+	}
+}
+
+// Same as above, but calling from the runtime is allowed.
+//
+// Using this function is necessary for any panic that may be
+// generated by runtime.sigpanic, since those are always called by the
+// runtime.
+func panicCheck2(err string) {
+	// panic allocates, so to avoid recursive malloc, turn panics
+	// during malloc into throws.
+	gp := getg()
+	if gp != nil && gp.m != nil && gp.m.mallocing != 0 {
+		throw(err)
+	}
+}
+
+// Many of the following panic entry-points turn into throws when they
+// happen in various runtime contexts. These should never happen in
+// the runtime, and if they do, they indicate a serious issue and
+// should not be caught by user code.
+//
+// The panic{Index,Slice,divide,shift} functions are called by
+// code generated by the compiler for out of bounds index expressions,
+// out of bounds slice expressions, division by zero, and shift by negative.
+// The panicdivide (again), panicoverflow, panicfloat, and panicmem
+// functions are called by the signal handler when a signal occurs
+// indicating the respective problem.
+//
+// Since panic{Index,Slice,shift} are never called directly, and
+// since the runtime package should never have an out of bounds slice
+// or array reference or negative shift, if we see those functions called from the
+// runtime package we turn the panic into a throw. That will dump the
+// entire runtime stack for easier debugging.
+//
+// The entry points called by the signal handler will be called from
+// runtime.sigpanic, so we can't disallow calls from the runtime to
+// these (they always look like they're called from the runtime).
+// Hence, for these, we just check for clearly bad runtime conditions.
+//
+// The panic{Index,Slice} functions are implemented in assembly and tail call
+// to the goPanic{Index,Slice} functions below. This is done so we can use
+// a space-minimal register calling convention.
+
+// failures in the comparisons for s[x], 0 <= x < y (y == len(s))
+//
+//go:yeswritebarrierrec
+func goPanicIndex(x int, y int) {
+	panicCheck1(getcallerpc(), "index out of range")
+	panic(boundsError{x: int64(x), signed: true, y: y, code: boundsIndex})
+}
+
+//go:yeswritebarrierrec
+func goPanicIndexU(x uint, y int) {
+	panicCheck1(getcallerpc(), "index out of range")
+	panic(boundsError{x: int64(x), signed: false, y: y, code: boundsIndex})
+}
+
+// failures in the comparisons for s[:x], 0 <= x <= y (y == len(s) or cap(s))
+//
+//go:yeswritebarrierrec
+func goPanicSliceAlen(x int, y int) {
+	panicCheck1(getcallerpc(), "slice bounds out of range")
+	panic(boundsError{x: int64(x), signed: true, y: y, code: boundsSliceAlen})
+}
+
+//go:yeswritebarrierrec
+func goPanicSliceAlenU(x uint, y int) {
+	panicCheck1(getcallerpc(), "slice bounds out of range")
+	panic(boundsError{x: int64(x), signed: false, y: y, code: boundsSliceAlen})
+}
+
+//go:yeswritebarrierrec
+func goPanicSliceAcap(x int, y int) {
+	panicCheck1(getcallerpc(), "slice bounds out of range")
+	panic(boundsError{x: int64(x), signed: true, y: y, code: boundsSliceAcap})
+}
+
+//go:yeswritebarrierrec
+func goPanicSliceAcapU(x uint, y int) {
+	panicCheck1(getcallerpc(), "slice bounds out of range")
+	panic(boundsError{x: int64(x), signed: false, y: y, code: boundsSliceAcap})
+}
+
+// failures in the comparisons for s[x:y], 0 <= x <= y
+//
+//go:yeswritebarrierrec
+func goPanicSliceB(x int, y int) {
+	panicCheck1(getcallerpc(), "slice bounds out of range")
+	panic(boundsError{x: int64(x), signed: true, y: y, code: boundsSliceB})
+}
+
+//go:yeswritebarrierrec
+func goPanicSliceBU(x uint, y int) {
+	panicCheck1(getcallerpc(), "slice bounds out of range")
+	panic(boundsError{x: int64(x), signed: false, y: y, code: boundsSliceB})
+}
+
+// failures in the comparisons for s[::x], 0 <= x <= y (y == len(s) or cap(s))
+func goPanicSlice3Alen(x int, y int) {
+	panicCheck1(getcallerpc(), "slice bounds out of range")
+	panic(boundsError{x: int64(x), signed: true, y: y, code: boundsSlice3Alen})
+}
+func goPanicSlice3AlenU(x uint, y int) {
+	panicCheck1(getcallerpc(), "slice bounds out of range")
+	panic(boundsError{x: int64(x), signed: false, y: y, code: boundsSlice3Alen})
+}
+func goPanicSlice3Acap(x int, y int) {
+	panicCheck1(getcallerpc(), "slice bounds out of range")
+	panic(boundsError{x: int64(x), signed: true, y: y, code: boundsSlice3Acap})
+}
+func goPanicSlice3AcapU(x uint, y int) {
+	panicCheck1(getcallerpc(), "slice bounds out of range")
+	panic(boundsError{x: int64(x), signed: false, y: y, code: boundsSlice3Acap})
+}
+
+// failures in the comparisons for s[:x:y], 0 <= x <= y
+func goPanicSlice3B(x int, y int) {
+	panicCheck1(getcallerpc(), "slice bounds out of range")
+	panic(boundsError{x: int64(x), signed: true, y: y, code: boundsSlice3B})
+}
+func goPanicSlice3BU(x uint, y int) {
+	panicCheck1(getcallerpc(), "slice bounds out of range")
+	panic(boundsError{x: int64(x), signed: false, y: y, code: boundsSlice3B})
+}
+
+// failures in the comparisons for s[x:y:], 0 <= x <= y
+func goPanicSlice3C(x int, y int) {
+	panicCheck1(getcallerpc(), "slice bounds out of range")
+	panic(boundsError{x: int64(x), signed: true, y: y, code: boundsSlice3C})
+}
+func goPanicSlice3CU(x uint, y int) {
+	panicCheck1(getcallerpc(), "slice bounds out of range")
+	panic(boundsError{x: int64(x), signed: false, y: y, code: boundsSlice3C})
+}
+
+// failures in the conversion (*[x]T)s, 0 <= x <= y, x == cap(s)
+func goPanicSliceConvert(x int, y int) {
+	panicCheck1(getcallerpc(), "slice length too short to convert to pointer to array")
+	panic(boundsError{x: int64(x), signed: true, y: y, code: boundsConvert})
+}
+
+// Implemented in assembly, as they take arguments in registers.
+// Declared here to mark them as ABIInternal.
+func panicIndex(x int, y int)
+func panicIndexU(x uint, y int)
+func panicSliceAlen(x int, y int)
+func panicSliceAlenU(x uint, y int)
+func panicSliceAcap(x int, y int)
+func panicSliceAcapU(x uint, y int)
+func panicSliceB(x int, y int)
+func panicSliceBU(x uint, y int)
+func panicSlice3Alen(x int, y int)
+func panicSlice3AlenU(x uint, y int)
+func panicSlice3Acap(x int, y int)
+func panicSlice3AcapU(x uint, y int)
+func panicSlice3B(x int, y int)
+func panicSlice3BU(x uint, y int)
+func panicSlice3C(x int, y int)
+func panicSlice3CU(x uint, y int)
+func panicSliceConvert(x int, y int)
+
+var shiftError = error(errorString("negative shift amount"))
+
+//go:yeswritebarrierrec
+func panicshift() {
+	panicCheck1(getcallerpc(), "negative shift amount")
+	panic(shiftError)
+}
+
+var divideError = error(errorString("integer divide by zero"))
+
+//go:yeswritebarrierrec
+func panicdivide() {
+	panicCheck2("integer divide by zero")
+	panic(divideError)
+}
+
+var overflowError = error(errorString("integer overflow"))
+
+func panicoverflow() {
+	panicCheck2("integer overflow")
+	panic(overflowError)
+}
+
+var floatError = error(errorString("floating point error"))
+
+func panicfloat() {
+	panicCheck2("floating point error")
+	panic(floatError)
+}
+
+var memoryError = error(errorString("invalid memory address or nil pointer dereference"))
+
+func panicmem() {
+	panicCheck2("invalid memory address or nil pointer dereference")
+	panic(memoryError)
+}
+
+func panicmemAddr(addr uintptr) {
+	panicCheck2("invalid memory address or nil pointer dereference")
+	panic(errorAddressString{msg: "invalid memory address or nil pointer dereference", addr: addr})
+}
+
+// Create a new deferred function fn, which has no arguments and results.
+// The compiler turns a defer statement into a call to this.
+func deferproc(fn func()) {
+	gp := getg()
+	if gp.m.curg != gp {
+		// go code on the system stack can't defer
+		throw("defer on system stack")
+	}
+
+	d := newdefer()
+	if d._panic != nil {
+		throw("deferproc: d.panic != nil after newdefer")
+	}
+	d.link = gp._defer
+	gp._defer = d
+	d.fn = fn
+	d.pc = getcallerpc()
+	// We must not be preempted between calling getcallersp and
+	// storing it to d.sp because getcallersp's result is a
+	// uintptr stack pointer.
+	d.sp = getcallersp()
+
+	// deferproc returns 0 normally.
+	// a deferred func that stops a panic
+	// makes the deferproc return 1.
+	// the code the compiler generates always
+	// checks the return value and jumps to the
+	// end of the function if deferproc returns != 0.
+	return0()
+	// No code can go here - the C return register has
+	// been set and must not be clobbered.
+}
+
+// deferprocStack queues a new deferred function with a defer record on the stack.
+// The defer record must have its fn field initialized.
+// All other fields can contain junk.
+// Nosplit because of the uninitialized pointer fields on the stack.
+//
+//go:nosplit
+func deferprocStack(d *_defer) {
+	gp := getg()
+	if gp.m.curg != gp {
+		// go code on the system stack can't defer
+		throw("defer on system stack")
+	}
+	// fn is already set.
+	// The other fields are junk on entry to deferprocStack and
+	// are initialized here.
+	d.started = false
+	d.heap = false
+	d.openDefer = false
+	d.sp = getcallersp()
+	d.pc = getcallerpc()
+	d.framepc = 0
+	d.varp = 0
+	// The lines below implement:
+	//   d.panic = nil
+	//   d.fd = nil
+	//   d.link = gp._defer
+	//   gp._defer = d
+	// But without write barriers. The first three are writes to
+	// the stack so they don't need a write barrier, and furthermore
+	// are to uninitialized memory, so they must not use a write barrier.
+	// The fourth write does not require a write barrier because we
+	// explicitly mark all the defer structures, so we don't need to
+	// keep track of pointers to them with a write barrier.
+	*(*uintptr)(unsafe.Pointer(&d._panic)) = 0
+	*(*uintptr)(unsafe.Pointer(&d.fd)) = 0
+	*(*uintptr)(unsafe.Pointer(&d.link)) = uintptr(unsafe.Pointer(gp._defer))
+	*(*uintptr)(unsafe.Pointer(&gp._defer)) = uintptr(unsafe.Pointer(d))
+
+	return0()
+	// No code can go here - the C return register has
+	// been set and must not be clobbered.
+}
+
+// Each P holds a pool for defers.
+
+// Allocate a Defer, usually using per-P pool.
+// Each defer must be released with freedefer.  The defer is not
+// added to any defer chain yet.
+func newdefer() *_defer {
+	var d *_defer
+	mp := acquirem()
+	pp := mp.p.ptr()
+	if len(pp.deferpool) == 0 && sched.deferpool != nil {
+		lock(&sched.deferlock)
+		for len(pp.deferpool) < cap(pp.deferpool)/2 && sched.deferpool != nil {
+			d := sched.deferpool
+			sched.deferpool = d.link
+			d.link = nil
+			pp.deferpool = append(pp.deferpool, d)
+		}
+		unlock(&sched.deferlock)
+	}
+	if n := len(pp.deferpool); n > 0 {
+		d = pp.deferpool[n-1]
+		pp.deferpool[n-1] = nil
+		pp.deferpool = pp.deferpool[:n-1]
+	}
+	releasem(mp)
+	mp, pp = nil, nil
+
+	if d == nil {
+		// Allocate new defer.
+		d = new(_defer)
+	}
+	d.heap = true
+	return d
+}
+
+// Free the given defer.
+// The defer cannot be used after this call.
+//
+// This is nosplit because the incoming defer is in a perilous state.
+// It's not on any defer list, so stack copying won't adjust stack
+// pointers in it (namely, d.link). Hence, if we were to copy the
+// stack, d could then contain a stale pointer.
+//
+//go:nosplit
+func freedefer(d *_defer) {
+	d.link = nil
+	// After this point we can copy the stack.
+
+	if d._panic != nil {
+		freedeferpanic()
+	}
+	if d.fn != nil {
+		freedeferfn()
+	}
+	if !d.heap {
+		return
+	}
+
+	mp := acquirem()
+	pp := mp.p.ptr()
+	if len(pp.deferpool) == cap(pp.deferpool) {
+		// Transfer half of local cache to the central cache.
+		var first, last *_defer
+		for len(pp.deferpool) > cap(pp.deferpool)/2 {
+			n := len(pp.deferpool)
+			d := pp.deferpool[n-1]
+			pp.deferpool[n-1] = nil
+			pp.deferpool = pp.deferpool[:n-1]
+			if first == nil {
+				first = d
+			} else {
+				last.link = d
+			}
+			last = d
+		}
+		lock(&sched.deferlock)
+		last.link = sched.deferpool
+		sched.deferpool = first
+		unlock(&sched.deferlock)
+	}
+
+	*d = _defer{}
+
+	pp.deferpool = append(pp.deferpool, d)
+
+	releasem(mp)
+	mp, pp = nil, nil
+}
+
+// Separate function so that it can split stack.
+// Windows otherwise runs out of stack space.
+func freedeferpanic() {
+	// _panic must be cleared before d is unlinked from gp.
+	throw("freedefer with d._panic != nil")
+}
+
+func freedeferfn() {
+	// fn must be cleared before d is unlinked from gp.
+	throw("freedefer with d.fn != nil")
+}
+
+// deferreturn runs deferred functions for the caller's frame.
+// The compiler inserts a call to this at the end of any
+// function which calls defer.
+func deferreturn() {
+	gp := getg()
+	for {
+		d := gp._defer
+		if d == nil {
+			return
+		}
+		sp := getcallersp()
+		if d.sp != sp {
+			return
+		}
+		if d.openDefer {
+			done := runOpenDeferFrame(gp, d)
+			if !done {
+				throw("unfinished open-coded defers in deferreturn")
+			}
+			gp._defer = d.link
+			freedefer(d)
+			// If this frame uses open defers, then this
+			// must be the only defer record for the
+			// frame, so we can just return.
+			return
+		}
+
+		fn := d.fn
+		d.fn = nil
+		gp._defer = d.link
+		freedefer(d)
+		fn()
+	}
+}
+
+// Goexit terminates the goroutine that calls it. No other goroutine is affected.
+// Goexit runs all deferred calls before terminating the goroutine. Because Goexit
+// is not a panic, any recover calls in those deferred functions will return nil.
+//
+// Calling Goexit from the main goroutine terminates that goroutine
+// without func main returning. Since func main has not returned,
+// the program continues execution of other goroutines.
+// If all other goroutines exit, the program crashes.
+func Goexit() {
+	// Run all deferred functions for the current goroutine.
+	// This code is similar to gopanic, see that implementation
+	// for detailed comments.
+	gp := getg()
+
+	// Create a panic object for Goexit, so we can recognize when it might be
+	// bypassed by a recover().
+	var p _panic
+	p.goexit = true
+	p.link = gp._panic
+	gp._panic = (*_panic)(noescape(unsafe.Pointer(&p)))
+
+	addOneOpenDeferFrame(gp, getcallerpc(), unsafe.Pointer(getcallersp()))
+	for {
+		d := gp._defer
+		if d == nil {
+			break
+		}
+		if d.started {
+			if d._panic != nil {
+				d._panic.aborted = true
+				d._panic = nil
+			}
+			if !d.openDefer {
+				d.fn = nil
+				gp._defer = d.link
+				freedefer(d)
+				continue
+			}
+		}
+		d.started = true
+		d._panic = (*_panic)(noescape(unsafe.Pointer(&p)))
+		if d.openDefer {
+			done := runOpenDeferFrame(gp, d)
+			if !done {
+				// We should always run all defers in the frame,
+				// since there is no panic associated with this
+				// defer that can be recovered.
+				throw("unfinished open-coded defers in Goexit")
+			}
+			if p.aborted {
+				// Since our current defer caused a panic and may
+				// have been already freed, just restart scanning
+				// for open-coded defers from this frame again.
+				addOneOpenDeferFrame(gp, getcallerpc(), unsafe.Pointer(getcallersp()))
+			} else {
+				addOneOpenDeferFrame(gp, 0, nil)
+			}
+		} else {
+			// Save the pc/sp in deferCallSave(), so we can "recover" back to this
+			// loop if necessary.
+			deferCallSave(&p, d.fn)
+		}
+		if p.aborted {
+			// We had a recursive panic in the defer d we started, and
+			// then did a recover in a defer that was further down the
+			// defer chain than d. In the case of an outstanding Goexit,
+			// we force the recover to return back to this loop. d will
+			// have already been freed if completed, so just continue
+			// immediately to the next defer on the chain.
+			p.aborted = false
+			continue
+		}
+		if gp._defer != d {
+			throw("bad defer entry in Goexit")
+		}
+		d._panic = nil
+		d.fn = nil
+		gp._defer = d.link
+		freedefer(d)
+		// Note: we ignore recovers here because Goexit isn't a panic
+	}
+	goexit1()
+}
+
+// Call all Error and String methods before freezing the world.
+// Used when crashing with panicking.
+func preprintpanics(p *_panic) {
+	defer func() {
+		text := "panic while printing panic value"
+		switch r := recover().(type) {
+		case nil:
+			// nothing to do
+		case string:
+			throw(text + ": " + r)
+		default:
+			throw(text + ": type " + efaceOf(&r)._type.string())
+		}
+	}()
+	for p != nil {
+		switch v := p.arg.(type) {
+		case error:
+			p.arg = v.Error()
+		case stringer:
+			p.arg = v.String()
+		}
+		p = p.link
+	}
+}
+
+// Print all currently active panics. Used when crashing.
+// Should only be called after preprintpanics.
+func printpanics(p *_panic) {
+	if p.link != nil {
+		printpanics(p.link)
+		if !p.link.goexit {
+			print("\t")
+		}
+	}
+	if p.goexit {
+		return
+	}
+	print("panic: ")
+	printany(p.arg)
+	if p.recovered {
+		print(" [recovered]")
+	}
+	print("\n")
+}
+
+// addOneOpenDeferFrame scans the stack (in gentraceback order, from inner frames to
+// outer frames) for the first frame (if any) with open-coded defers. If it finds
+// one, it adds a single entry to the defer chain for that frame. The entry added
+// represents all the defers in the associated open defer frame, and is sorted in
+// order with respect to any non-open-coded defers.
+//
+// addOneOpenDeferFrame stops (possibly without adding a new entry) if it encounters
+// an in-progress open defer entry. An in-progress open defer entry means there has
+// been a new panic because of a defer in the associated frame. addOneOpenDeferFrame
+// does not add an open defer entry past a started entry, because that started entry
+// still needs to finished, and addOneOpenDeferFrame will be called when that started
+// entry is completed. The defer removal loop in gopanic() similarly stops at an
+// in-progress defer entry. Together, addOneOpenDeferFrame and the defer removal loop
+// ensure the invariant that there is no open defer entry further up the stack than
+// an in-progress defer, and also that the defer removal loop is guaranteed to remove
+// all not-in-progress open defer entries from the defer chain.
+//
+// If sp is non-nil, addOneOpenDeferFrame starts the stack scan from the frame
+// specified by sp. If sp is nil, it uses the sp from the current defer record (which
+// has just been finished). Hence, it continues the stack scan from the frame of the
+// defer that just finished. It skips any frame that already has a (not-in-progress)
+// open-coded _defer record in the defer chain.
+//
+// Note: All entries of the defer chain (including this new open-coded entry) have
+// their pointers (including sp) adjusted properly if the stack moves while
+// running deferred functions. Also, it is safe to pass in the sp arg (which is
+// the direct result of calling getcallersp()), because all pointer variables
+// (including arguments) are adjusted as needed during stack copies.
+func addOneOpenDeferFrame(gp *g, pc uintptr, sp unsafe.Pointer) {
+	var prevDefer *_defer
+	if sp == nil {
+		prevDefer = gp._defer
+		pc = prevDefer.framepc
+		sp = unsafe.Pointer(prevDefer.sp)
+	}
+	systemstack(func() {
+		gentraceback(pc, uintptr(sp), 0, gp, 0, nil, 0x7fffffff,
+			func(frame *stkframe, unused unsafe.Pointer) bool {
+				if prevDefer != nil && prevDefer.sp == frame.sp {
+					// Skip the frame for the previous defer that
+					// we just finished (and was used to set
+					// where we restarted the stack scan)
+					return true
+				}
+				f := frame.fn
+				fd := funcdata(f, _FUNCDATA_OpenCodedDeferInfo)
+				if fd == nil {
+					return true
+				}
+				// Insert the open defer record in the
+				// chain, in order sorted by sp.
+				d := gp._defer
+				var prev *_defer
+				for d != nil {
+					dsp := d.sp
+					if frame.sp < dsp {
+						break
+					}
+					if frame.sp == dsp {
+						if !d.openDefer {
+							throw("duplicated defer entry")
+						}
+						// Don't add any record past an
+						// in-progress defer entry. We don't
+						// need it, and more importantly, we
+						// want to keep the invariant that
+						// there is no open defer entry
+						// passed an in-progress entry (see
+						// header comment).
+						if d.started {
+							return false
+						}
+						return true
+					}
+					prev = d
+					d = d.link
+				}
+				if frame.fn.deferreturn == 0 {
+					throw("missing deferreturn")
+				}
+
+				d1 := newdefer()
+				d1.openDefer = true
+				d1._panic = nil
+				// These are the pc/sp to set after we've
+				// run a defer in this frame that did a
+				// recover. We return to a special
+				// deferreturn that runs any remaining
+				// defers and then returns from the
+				// function.
+				d1.pc = frame.fn.entry() + uintptr(frame.fn.deferreturn)
+				d1.varp = frame.varp
+				d1.fd = fd
+				// Save the SP/PC associated with current frame,
+				// so we can continue stack trace later if needed.
+				d1.framepc = frame.pc
+				d1.sp = frame.sp
+				d1.link = d
+				if prev == nil {
+					gp._defer = d1
+				} else {
+					prev.link = d1
+				}
+				// Stop stack scanning after adding one open defer record
+				return false
+			},
+			nil, 0)
+	})
+}
+
+// readvarintUnsafe reads the uint32 in varint format starting at fd, and returns the
+// uint32 and a pointer to the byte following the varint.
+//
+// There is a similar function runtime.readvarint, which takes a slice of bytes,
+// rather than an unsafe pointer. These functions are duplicated, because one of
+// the two use cases for the functions would get slower if the functions were
+// combined.
+func readvarintUnsafe(fd unsafe.Pointer) (uint32, unsafe.Pointer) {
+	var r uint32
+	var shift int
+	for {
+		b := *(*uint8)((unsafe.Pointer(fd)))
+		fd = add(fd, unsafe.Sizeof(b))
+		if b < 128 {
+			return r + uint32(b)<<shift, fd
+		}
+		r += ((uint32(b) &^ 128) << shift)
+		shift += 7
+		if shift > 28 {
+			panic("Bad varint")
+		}
+	}
+}
+
+// runOpenDeferFrame runs the active open-coded defers in the frame specified by
+// d. It normally processes all active defers in the frame, but stops immediately
+// if a defer does a successful recover. It returns true if there are no
+// remaining defers to run in the frame.
+func runOpenDeferFrame(gp *g, d *_defer) bool {
+	done := true
+	fd := d.fd
+
+	deferBitsOffset, fd := readvarintUnsafe(fd)
+	nDefers, fd := readvarintUnsafe(fd)
+	deferBits := *(*uint8)(unsafe.Pointer(d.varp - uintptr(deferBitsOffset)))
+
+	for i := int(nDefers) - 1; i >= 0; i-- {
+		// read the funcdata info for this defer
+		var closureOffset uint32
+		closureOffset, fd = readvarintUnsafe(fd)
+		if deferBits&(1<<i) == 0 {
+			continue
+		}
+		closure := *(*func())(unsafe.Pointer(d.varp - uintptr(closureOffset)))
+		d.fn = closure
+		deferBits = deferBits &^ (1 << i)
+		*(*uint8)(unsafe.Pointer(d.varp - uintptr(deferBitsOffset))) = deferBits
+		p := d._panic
+		// Call the defer. Note that this can change d.varp if
+		// the stack moves.
+		deferCallSave(p, d.fn)
+		if p != nil && p.aborted {
+			break
+		}
+		d.fn = nil
+		if d._panic != nil && d._panic.recovered {
+			done = deferBits == 0
+			break
+		}
+	}
+
+	return done
+}
+
+// deferCallSave calls fn() after saving the caller's pc and sp in the
+// panic record. This allows the runtime to return to the Goexit defer
+// processing loop, in the unusual case where the Goexit may be
+// bypassed by a successful recover.
+//
+// This is marked as a wrapper by the compiler so it doesn't appear in
+// tracebacks.
+func deferCallSave(p *_panic, fn func()) {
+	if p != nil {
+		p.argp = unsafe.Pointer(getargp())
+		p.pc = getcallerpc()
+		p.sp = unsafe.Pointer(getcallersp())
+	}
+	fn()
+	if p != nil {
+		p.pc = 0
+		p.sp = unsafe.Pointer(nil)
+	}
+}
+
+// The implementation of the predeclared function panic.
+func gopanic(e any) {
+	gp := getg()
+	if gp.m.curg != gp {
+		print("panic: ")
+		printany(e)
+		print("\n")
+		throw("panic on system stack")
+	}
+
+	if gp.m.mallocing != 0 {
+		print("panic: ")
+		printany(e)
+		print("\n")
+		throw("panic during malloc")
+	}
+	if gp.m.preemptoff != "" {
+		print("panic: ")
+		printany(e)
+		print("\n")
+		print("preempt off reason: ")
+		print(gp.m.preemptoff)
+		print("\n")
+		throw("panic during preemptoff")
+	}
+	if gp.m.locks != 0 {
+		print("panic: ")
+		printany(e)
+		print("\n")
+		throw("panic holding locks")
+	}
+
+	var p _panic
+	p.arg = e
+	p.link = gp._panic
+	gp._panic = (*_panic)(noescape(unsafe.Pointer(&p)))
+
+	atomic.Xadd(&runningPanicDefers, 1)
+
+	// By calculating getcallerpc/getcallersp here, we avoid scanning the
+	// gopanic frame (stack scanning is slow...)
+	addOneOpenDeferFrame(gp, getcallerpc(), unsafe.Pointer(getcallersp()))
+
+	for {
+		d := gp._defer
+		if d == nil {
+			break
+		}
+
+		// If defer was started by earlier panic or Goexit (and, since we're back here, that triggered a new panic),
+		// take defer off list. An earlier panic will not continue running, but we will make sure below that an
+		// earlier Goexit does continue running.
+		if d.started {
+			if d._panic != nil {
+				d._panic.aborted = true
+			}
+			d._panic = nil
+			if !d.openDefer {
+				// For open-coded defers, we need to process the
+				// defer again, in case there are any other defers
+				// to call in the frame (not including the defer
+				// call that caused the panic).
+				d.fn = nil
+				gp._defer = d.link
+				freedefer(d)
+				continue
+			}
+		}
+
+		// Mark defer as started, but keep on list, so that traceback
+		// can find and update the defer's argument frame if stack growth
+		// or a garbage collection happens before executing d.fn.
+		d.started = true
+
+		// Record the panic that is running the defer.
+		// If there is a new panic during the deferred call, that panic
+		// will find d in the list and will mark d._panic (this panic) aborted.
+		d._panic = (*_panic)(noescape(unsafe.Pointer(&p)))
+
+		done := true
+		if d.openDefer {
+			done = runOpenDeferFrame(gp, d)
+			if done && !d._panic.recovered {
+				addOneOpenDeferFrame(gp, 0, nil)
+			}
+		} else {
+			p.argp = unsafe.Pointer(getargp())
+			d.fn()
+		}
+		p.argp = nil
+
+		// Deferred function did not panic. Remove d.
+		if gp._defer != d {
+			throw("bad defer entry in panic")
+		}
+		d._panic = nil
+
+		// trigger shrinkage to test stack copy. See stack_test.go:TestStackPanic
+		//GC()
+
+		pc := d.pc
+		sp := unsafe.Pointer(d.sp) // must be pointer so it gets adjusted during stack copy
+		if done {
+			d.fn = nil
+			gp._defer = d.link
+			freedefer(d)
+		}
+		if p.recovered {
+			gp._panic = p.link
+			if gp._panic != nil && gp._panic.goexit && gp._panic.aborted {
+				// A normal recover would bypass/abort the Goexit.  Instead,
+				// we return to the processing loop of the Goexit.
+				gp.sigcode0 = uintptr(gp._panic.sp)
+				gp.sigcode1 = uintptr(gp._panic.pc)
+				mcall(recovery)
+				throw("bypassed recovery failed") // mcall should not return
+			}
+			atomic.Xadd(&runningPanicDefers, -1)
+
+			// After a recover, remove any remaining non-started,
+			// open-coded defer entries, since the corresponding defers
+			// will be executed normally (inline). Any such entry will
+			// become stale once we run the corresponding defers inline
+			// and exit the associated stack frame. We only remove up to
+			// the first started (in-progress) open defer entry, not
+			// including the current frame, since any higher entries will
+			// be from a higher panic in progress, and will still be
+			// needed.
+			d := gp._defer
+			var prev *_defer
+			if !done {
+				// Skip our current frame, if not done. It is
+				// needed to complete any remaining defers in
+				// deferreturn()
+				prev = d
+				d = d.link
+			}
+			for d != nil {
+				if d.started {
+					// This defer is started but we
+					// are in the middle of a
+					// defer-panic-recover inside of
+					// it, so don't remove it or any
+					// further defer entries
+					break
+				}
+				if d.openDefer {
+					if prev == nil {
+						gp._defer = d.link
+					} else {
+						prev.link = d.link
+					}
+					newd := d.link
+					freedefer(d)
+					d = newd
+				} else {
+					prev = d
+					d = d.link
+				}
+			}
+
+			gp._panic = p.link
+			// Aborted panics are marked but remain on the g.panic list.
+			// Remove them from the list.
+			for gp._panic != nil && gp._panic.aborted {
+				gp._panic = gp._panic.link
+			}
+			if gp._panic == nil { // must be done with signal
+				gp.sig = 0
+			}
+			// Pass information about recovering frame to recovery.
+			gp.sigcode0 = uintptr(sp)
+			gp.sigcode1 = pc
+			mcall(recovery)
+			throw("recovery failed") // mcall should not return
+		}
+	}
+
+	// ran out of deferred calls - old-school panic now
+	// Because it is unsafe to call arbitrary user code after freezing
+	// the world, we call preprintpanics to invoke all necessary Error
+	// and String methods to prepare the panic strings before startpanic.
+	preprintpanics(gp._panic)
+
+	fatalpanic(gp._panic) // should not return
+	*(*int)(nil) = 0      // not reached
+}
+
+// getargp returns the location where the caller
+// writes outgoing function call arguments.
+//
+//go:nosplit
+//go:noinline
+func getargp() uintptr {
+	return getcallersp() + sys.MinFrameSize
+}
+
+// The implementation of the predeclared function recover.
+// Cannot split the stack because it needs to reliably
+// find the stack segment of its caller.
+//
+// TODO(rsc): Once we commit to CopyStackAlways,
+// this doesn't need to be nosplit.
+//
+//go:nosplit
+func gorecover(argp uintptr) any {
+	// Must be in a function running as part of a deferred call during the panic.
+	// Must be called from the topmost function of the call
+	// (the function used in the defer statement).
+	// p.argp is the argument pointer of that topmost deferred function call.
+	// Compare against argp reported by caller.
+	// If they match, the caller is the one who can recover.
+	gp := getg()
+	p := gp._panic
+	if p != nil && !p.goexit && !p.recovered && argp == uintptr(p.argp) {
+		p.recovered = true
+		return p.arg
+	}
+	return nil
+}
+
+//go:linkname sync_throw sync.throw
+func sync_throw(s string) {
+	throw(s)
+}
+
+//go:linkname sync_fatal sync.fatal
+func sync_fatal(s string) {
+	fatal(s)
+}
+
+// throw triggers a fatal error that dumps a stack trace and exits.
+//
+// throw should be used for runtime-internal fatal errors where Go itself,
+// rather than user code, may be at fault for the failure.
+//
+//go:nosplit
+func throw(s string) {
+	// Everything throw does should be recursively nosplit so it
+	// can be called even when it's unsafe to grow the stack.
+	systemstack(func() {
+		print("fatal error: ", s, "\n")
+	})
+
+	fatalthrow(throwTypeRuntime)
+}
+
+// fatal triggers a fatal error that dumps a stack trace and exits.
+//
+// fatal is equivalent to throw, but is used when user code is expected to be
+// at fault for the failure, such as racing map writes.
+//
+// fatal does not include runtime frames, system goroutines, or frame metadata
+// (fp, sp, pc) in the stack trace unless GOTRACEBACK=system or higher.
+//
+//go:nosplit
+func fatal(s string) {
+	// Everything fatal does should be recursively nosplit so it
+	// can be called even when it's unsafe to grow the stack.
+	systemstack(func() {
+		print("fatal error: ", s, "\n")
+	})
+
+	fatalthrow(throwTypeUser)
+}
+
+// runningPanicDefers is non-zero while running deferred functions for panic.
+// runningPanicDefers is incremented and decremented atomically.
+// This is used to try hard to get a panic stack trace out when exiting.
+var runningPanicDefers uint32
+
+// panicking is non-zero when crashing the program for an unrecovered panic.
+// panicking is incremented and decremented atomically.
+var panicking uint32
+
+// paniclk is held while printing the panic information and stack trace,
+// so that two concurrent panics don't overlap their output.
+var paniclk mutex
+
+// Unwind the stack after a deferred function calls recover
+// after a panic. Then arrange to continue running as though
+// the caller of the deferred function returned normally.
+func recovery(gp *g) {
+	// Info about defer passed in G struct.
+	sp := gp.sigcode0
+	pc := gp.sigcode1
+
+	// d's arguments need to be in the stack.
+	if sp != 0 && (sp < gp.stack.lo || gp.stack.hi < sp) {
+		print("recover: ", hex(sp), " not in [", hex(gp.stack.lo), ", ", hex(gp.stack.hi), "]\n")
+		throw("bad recovery")
+	}
+
+	// Make the deferproc for this d return again,
+	// this time returning 1. The calling function will
+	// jump to the standard return epilogue.
+	gp.sched.sp = sp
+	gp.sched.pc = pc
+	gp.sched.lr = 0
+	gp.sched.ret = 1
+	gogo(&gp.sched)
+}
+
+// fatalthrow implements an unrecoverable runtime throw. It freezes the
+// system, prints stack traces starting from its caller, and terminates the
+// process.
+//
+//go:nosplit
+func fatalthrow(t throwType) {
+	pc := getcallerpc()
+	sp := getcallersp()
+	gp := getg()
+
+	if gp.m.throwing == throwTypeNone {
+		gp.m.throwing = t
+	}
+
+	// Switch to the system stack to avoid any stack growth, which may make
+	// things worse if the runtime is in a bad state.
+	systemstack(func() {
+		startpanic_m()
+
+		if dopanic_m(gp, pc, sp) {
+			// crash uses a decent amount of nosplit stack and we're already
+			// low on stack in throw, so crash on the system stack (unlike
+			// fatalpanic).
+			crash()
+		}
+
+		exit(2)
+	})
+
+	*(*int)(nil) = 0 // not reached
+}
+
+// fatalpanic implements an unrecoverable panic. It is like fatalthrow, except
+// that if msgs != nil, fatalpanic also prints panic messages and decrements
+// runningPanicDefers once main is blocked from exiting.
+//
+//go:nosplit
+func fatalpanic(msgs *_panic) {
+	pc := getcallerpc()
+	sp := getcallersp()
+	gp := getg()
+	var docrash bool
+	// Switch to the system stack to avoid any stack growth, which
+	// may make things worse if the runtime is in a bad state.
+	systemstack(func() {
+		if startpanic_m() && msgs != nil {
+			// There were panic messages and startpanic_m
+			// says it's okay to try to print them.
+
+			// startpanic_m set panicking, which will
+			// block main from exiting, so now OK to
+			// decrement runningPanicDefers.
+			atomic.Xadd(&runningPanicDefers, -1)
+
+			printpanics(msgs)
+		}
+
+		docrash = dopanic_m(gp, pc, sp)
+	})
+
+	if docrash {
+		// By crashing outside the above systemstack call, debuggers
+		// will not be confused when generating a backtrace.
+		// Function crash is marked nosplit to avoid stack growth.
+		crash()
+	}
+
+	systemstack(func() {
+		exit(2)
+	})
+
+	*(*int)(nil) = 0 // not reached
+}
+
+// startpanic_m prepares for an unrecoverable panic.
+//
+// It returns true if panic messages should be printed, or false if
+// the runtime is in bad shape and should just print stacks.
+//
+// It must not have write barriers even though the write barrier
+// explicitly ignores writes once dying > 0. Write barriers still
+// assume that g.m.p != nil, and this function may not have P
+// in some contexts (e.g. a panic in a signal handler for a signal
+// sent to an M with no P).
+//
+//go:nowritebarrierrec
+func startpanic_m() bool {
+	_g_ := getg()
+	if mheap_.cachealloc.size == 0 { // very early
+		print("runtime: panic before malloc heap initialized\n")
+	}
+	// Disallow malloc during an unrecoverable panic. A panic
+	// could happen in a signal handler, or in a throw, or inside
+	// malloc itself. We want to catch if an allocation ever does
+	// happen (even if we're not in one of these situations).
+	_g_.m.mallocing++
+
+	// If we're dying because of a bad lock count, set it to a
+	// good lock count so we don't recursively panic below.
+	if _g_.m.locks < 0 {
+		_g_.m.locks = 1
+	}
+
+	switch _g_.m.dying {
+	case 0:
+		// Setting dying >0 has the side-effect of disabling this G's writebuf.
+		_g_.m.dying = 1
+		atomic.Xadd(&panicking, 1)
+		lock(&paniclk)
+		if debug.schedtrace > 0 || debug.scheddetail > 0 {
+			schedtrace(true)
+		}
+		freezetheworld()
+		return true
+	case 1:
+		// Something failed while panicking.
+		// Just print a stack trace and exit.
+		_g_.m.dying = 2
+		print("panic during panic\n")
+		return false
+	case 2:
+		// This is a genuine bug in the runtime, we couldn't even
+		// print the stack trace successfully.
+		_g_.m.dying = 3
+		print("stack trace unavailable\n")
+		exit(4)
+		fallthrough
+	default:
+		// Can't even print! Just exit.
+		exit(5)
+		return false // Need to return something.
+	}
+}
+
+var didothers bool
+var deadlock mutex
+
+func dopanic_m(gp *g, pc, sp uintptr) bool {
+	if gp.sig != 0 {
+		signame := signame(gp.sig)
+		if signame != "" {
+			print("[signal ", signame)
+		} else {
+			print("[signal ", hex(gp.sig))
+		}
+		print(" code=", hex(gp.sigcode0), " addr=", hex(gp.sigcode1), " pc=", hex(gp.sigpc), "]\n")
+	}
+
+	level, all, docrash := gotraceback()
+	_g_ := getg()
+	if level > 0 {
+		if gp != gp.m.curg {
+			all = true
+		}
+		if gp != gp.m.g0 {
+			print("\n")
+			goroutineheader(gp)
+			traceback(pc, sp, 0, gp)
+		} else if level >= 2 || _g_.m.throwing >= throwTypeRuntime {
+			print("\nruntime stack:\n")
+			traceback(pc, sp, 0, gp)
+		}
+		if !didothers && all {
+			didothers = true
+			tracebackothers(gp)
+		}
+	}
+	unlock(&paniclk)
+
+	if atomic.Xadd(&panicking, -1) != 0 {
+		// Some other m is panicking too.
+		// Let it print what it needs to print.
+		// Wait forever without chewing up cpu.
+		// It will exit when it's done.
+		lock(&deadlock)
+		lock(&deadlock)
+	}
+
+	printDebugLog()
+
+	return docrash
+}
+
+// canpanic returns false if a signal should throw instead of
+// panicking.
+//
+//go:nosplit
+func canpanic(gp *g) bool {
+	// Note that g is m->gsignal, different from gp.
+	// Note also that g->m can change at preemption, so m can go stale
+	// if this function ever makes a function call.
+	_g_ := getg()
+	mp := _g_.m
+
+	// Is it okay for gp to panic instead of crashing the program?
+	// Yes, as long as it is running Go code, not runtime code,
+	// and not stuck in a system call.
+	if gp == nil || gp != mp.curg {
+		return false
+	}
+	if mp.locks != 0 || mp.mallocing != 0 || mp.throwing != throwTypeNone || mp.preemptoff != "" || mp.dying != 0 {
+		return false
+	}
+	status := readgstatus(gp)
+	if status&^_Gscan != _Grunning || gp.syscallsp != 0 {
+		return false
+	}
+	if GOOS == "windows" && mp.libcallsp != 0 {
+		return false
+	}
+	return true
+}
+
+// shouldPushSigpanic reports whether pc should be used as sigpanic's
+// return PC (pushing a frame for the call). Otherwise, it should be
+// left alone so that LR is used as sigpanic's return PC, effectively
+// replacing the top-most frame with sigpanic. This is used by
+// preparePanic.
+func shouldPushSigpanic(gp *g, pc, lr uintptr) bool {
+	if pc == 0 {
+		// Probably a call to a nil func. The old LR is more
+		// useful in the stack trace. Not pushing the frame
+		// will make the trace look like a call to sigpanic
+		// instead. (Otherwise the trace will end at sigpanic
+		// and we won't get to see who faulted.)
+		return false
+	}
+	// If we don't recognize the PC as code, but we do recognize
+	// the link register as code, then this assumes the panic was
+	// caused by a call to non-code. In this case, we want to
+	// ignore this call to make unwinding show the context.
+	//
+	// If we running C code, we're not going to recognize pc as a
+	// Go function, so just assume it's good. Otherwise, traceback
+	// may try to read a stale LR that looks like a Go code
+	// pointer and wander into the woods.
+	if gp.m.incgo || findfunc(pc).valid() {
+		// This wasn't a bad call, so use PC as sigpanic's
+		// return PC.
+		return true
+	}
+	if findfunc(lr).valid() {
+		// This was a bad call, but the LR is good, so use the
+		// LR as sigpanic's return PC.
+		return false
+	}
+	// Neither the PC or LR is good. Hopefully pushing a frame
+	// will work.
+	return true
+}
+
+// isAbortPC reports whether pc is the program counter at which
+// runtime.abort raises a signal.
+//
+// It is nosplit because it's part of the isgoexception
+// implementation.
+//
+//go:nosplit
+func isAbortPC(pc uintptr) bool {
+	f := findfunc(pc)
+	if !f.valid() {
+		return false
+	}
+	return f.funcID == funcID_abort
+}
diff --git a/contrib/go/_std_1.18/src/runtime/plugin.go b/contrib/go/_std_1.19/src/runtime/plugin.go
index a61dcc3b5d..a61dcc3b5d 100644
--- a/contrib/go/_std_1.18/src/runtime/plugin.go
+++ b/contrib/go/_std_1.19/src/runtime/plugin.go
diff --git a/contrib/go/_std_1.18/src/runtime/preempt.go b/contrib/go/_std_1.19/src/runtime/preempt.go
index da24f5042c..da24f5042c 100644
--- a/contrib/go/_std_1.18/src/runtime/preempt.go
+++ b/contrib/go/_std_1.19/src/runtime/preempt.go
diff --git a/contrib/go/_std_1.18/src/runtime/preempt_amd64.s b/contrib/go/_std_1.19/src/runtime/preempt_amd64.s
index 31f7c8b66f..31f7c8b66f 100644
--- a/contrib/go/_std_1.18/src/runtime/preempt_amd64.s
+++ b/contrib/go/_std_1.19/src/runtime/preempt_amd64.s
diff --git a/contrib/go/_std_1.18/src/runtime/preempt_nonwindows.go b/contrib/go/_std_1.19/src/runtime/preempt_nonwindows.go
index d6a2408cb7..d6a2408cb7 100644
--- a/contrib/go/_std_1.18/src/runtime/preempt_nonwindows.go
+++ b/contrib/go/_std_1.19/src/runtime/preempt_nonwindows.go
diff --git a/contrib/go/_std_1.18/src/runtime/print.go b/contrib/go/_std_1.19/src/runtime/print.go
index b2a642bb86..b2a642bb86 100644
--- a/contrib/go/_std_1.18/src/runtime/print.go
+++ b/contrib/go/_std_1.19/src/runtime/print.go
diff --git a/contrib/go/_std_1.19/src/runtime/proc.go b/contrib/go/_std_1.19/src/runtime/proc.go
new file mode 100644
index 0000000000..3991a48b10
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/proc.go
@@ -0,0 +1,6343 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"internal/abi"
+	"internal/cpu"
+	"internal/goarch"
+	"runtime/internal/atomic"
+	"runtime/internal/sys"
+	"unsafe"
+)
+
+// set using cmd/go/internal/modload.ModInfoProg
+var modinfo string
+
+// Goroutine scheduler
+// The scheduler's job is to distribute ready-to-run goroutines over worker threads.
+//
+// The main concepts are:
+// G - goroutine.
+// M - worker thread, or machine.
+// P - processor, a resource that is required to execute Go code.
+//     M must have an associated P to execute Go code, however it can be
+//     blocked or in a syscall w/o an associated P.
+//
+// Design doc at https://golang.org/s/go11sched.
+
+// Worker thread parking/unparking.
+// We need to balance between keeping enough running worker threads to utilize
+// available hardware parallelism and parking excessive running worker threads
+// to conserve CPU resources and power. This is not simple for two reasons:
+// (1) scheduler state is intentionally distributed (in particular, per-P work
+// queues), so it is not possible to compute global predicates on fast paths;
+// (2) for optimal thread management we would need to know the future (don't park
+// a worker thread when a new goroutine will be readied in near future).
+//
+// Three rejected approaches that would work badly:
+// 1. Centralize all scheduler state (would inhibit scalability).
+// 2. Direct goroutine handoff. That is, when we ready a new goroutine and there
+//    is a spare P, unpark a thread and handoff it the thread and the goroutine.
+//    This would lead to thread state thrashing, as the thread that readied the
+//    goroutine can be out of work the very next moment, we will need to park it.
+//    Also, it would destroy locality of computation as we want to preserve
+//    dependent goroutines on the same thread; and introduce additional latency.
+// 3. Unpark an additional thread whenever we ready a goroutine and there is an
+//    idle P, but don't do handoff. This would lead to excessive thread parking/
+//    unparking as the additional threads will instantly park without discovering
+//    any work to do.
+//
+// The current approach:
+//
+// This approach applies to three primary sources of potential work: readying a
+// goroutine, new/modified-earlier timers, and idle-priority GC. See below for
+// additional details.
+//
+// We unpark an additional thread when we submit work if (this is wakep()):
+// 1. There is an idle P, and
+// 2. There are no "spinning" worker threads.
+//
+// A worker thread is considered spinning if it is out of local work and did
+// not find work in the global run queue or netpoller; the spinning state is
+// denoted in m.spinning and in sched.nmspinning. Threads unparked this way are
+// also considered spinning; we don't do goroutine handoff so such threads are
+// out of work initially. Spinning threads spin on looking for work in per-P
+// run queues and timer heaps or from the GC before parking. If a spinning
+// thread finds work it takes itself out of the spinning state and proceeds to
+// execution. If it does not find work it takes itself out of the spinning
+// state and then parks.
+//
+// If there is at least one spinning thread (sched.nmspinning>1), we don't
+// unpark new threads when submitting work. To compensate for that, if the last
+// spinning thread finds work and stops spinning, it must unpark a new spinning
+// thread.  This approach smooths out unjustified spikes of thread unparking,
+// but at the same time guarantees eventual maximal CPU parallelism
+// utilization.
+//
+// The main implementation complication is that we need to be very careful
+// during spinning->non-spinning thread transition. This transition can race
+// with submission of new work, and either one part or another needs to unpark
+// another worker thread. If they both fail to do that, we can end up with
+// semi-persistent CPU underutilization.
+//
+// The general pattern for submission is:
+// 1. Submit work to the local run queue, timer heap, or GC state.
+// 2. #StoreLoad-style memory barrier.
+// 3. Check sched.nmspinning.
+//
+// The general pattern for spinning->non-spinning transition is:
+// 1. Decrement nmspinning.
+// 2. #StoreLoad-style memory barrier.
+// 3. Check all per-P work queues and GC for new work.
+//
+// Note that all this complexity does not apply to global run queue as we are
+// not sloppy about thread unparking when submitting to global queue. Also see
+// comments for nmspinning manipulation.
+//
+// How these different sources of work behave varies, though it doesn't affect
+// the synchronization approach:
+// * Ready goroutine: this is an obvious source of work; the goroutine is
+//   immediately ready and must run on some thread eventually.
+// * New/modified-earlier timer: The current timer implementation (see time.go)
+//   uses netpoll in a thread with no work available to wait for the soonest
+//   timer. If there is no thread waiting, we want a new spinning thread to go
+//   wait.
+// * Idle-priority GC: The GC wakes a stopped idle thread to contribute to
+//   background GC work (note: currently disabled per golang.org/issue/19112).
+//   Also see golang.org/issue/44313, as this should be extended to all GC
+//   workers.
+
+var (
+	m0           m
+	g0           g
+	mcache0      *mcache
+	raceprocctx0 uintptr
+)
+
+//go:linkname runtime_inittask runtime..inittask
+var runtime_inittask initTask
+
+//go:linkname main_inittask main..inittask
+var main_inittask initTask
+
+// main_init_done is a signal used by cgocallbackg that initialization
+// has been completed. It is made before _cgo_notify_runtime_init_done,
+// so all cgo calls can rely on it existing. When main_init is complete,
+// it is closed, meaning cgocallbackg can reliably receive from it.
+var main_init_done chan bool
+
+//go:linkname main_main main.main
+func main_main()
+
+// mainStarted indicates that the main M has started.
+var mainStarted bool
+
+// runtimeInitTime is the nanotime() at which the runtime started.
+var runtimeInitTime int64
+
+// Value to use for signal mask for newly created M's.
+var initSigmask sigset
+
+// The main goroutine.
+func main() {
+	g := getg()
+
+	// Racectx of m0->g0 is used only as the parent of the main goroutine.
+	// It must not be used for anything else.
+	g.m.g0.racectx = 0
+
+	// Max stack size is 1 GB on 64-bit, 250 MB on 32-bit.
+	// Using decimal instead of binary GB and MB because
+	// they look nicer in the stack overflow failure message.
+	if goarch.PtrSize == 8 {
+		maxstacksize = 1000000000
+	} else {
+		maxstacksize = 250000000
+	}
+
+	// An upper limit for max stack size. Used to avoid random crashes
+	// after calling SetMaxStack and trying to allocate a stack that is too big,
+	// since stackalloc works with 32-bit sizes.
+	maxstackceiling = 2 * maxstacksize
+
+	// Allow newproc to start new Ms.
+	mainStarted = true
+
+	if GOARCH != "wasm" { // no threads on wasm yet, so no sysmon
+		systemstack(func() {
+			newm(sysmon, nil, -1)
+		})
+	}
+
+	// Lock the main goroutine onto this, the main OS thread,
+	// during initialization. Most programs won't care, but a few
+	// do require certain calls to be made by the main thread.
+	// Those can arrange for main.main to run in the main thread
+	// by calling runtime.LockOSThread during initialization
+	// to preserve the lock.
+	lockOSThread()
+
+	if g.m != &m0 {
+		throw("runtime.main not on m0")
+	}
+
+	// Record when the world started.
+	// Must be before doInit for tracing init.
+	runtimeInitTime = nanotime()
+	if runtimeInitTime == 0 {
+		throw("nanotime returning zero")
+	}
+
+	if debug.inittrace != 0 {
+		inittrace.id = getg().goid
+		inittrace.active = true
+	}
+
+	doInit(&runtime_inittask) // Must be before defer.
+
+	// Defer unlock so that runtime.Goexit during init does the unlock too.
+	needUnlock := true
+	defer func() {
+		if needUnlock {
+			unlockOSThread()
+		}
+	}()
+
+	gcenable()
+
+	main_init_done = make(chan bool)
+	if iscgo {
+		if _cgo_thread_start == nil {
+			throw("_cgo_thread_start missing")
+		}
+		if GOOS != "windows" {
+			if _cgo_setenv == nil {
+				throw("_cgo_setenv missing")
+			}
+			if _cgo_unsetenv == nil {
+				throw("_cgo_unsetenv missing")
+			}
+		}
+		if _cgo_notify_runtime_init_done == nil {
+			throw("_cgo_notify_runtime_init_done missing")
+		}
+		// Start the template thread in case we enter Go from
+		// a C-created thread and need to create a new thread.
+		startTemplateThread()
+		cgocall(_cgo_notify_runtime_init_done, nil)
+	}
+
+	doInit(&main_inittask)
+
+	// Disable init tracing after main init done to avoid overhead
+	// of collecting statistics in malloc and newproc
+	inittrace.active = false
+
+	close(main_init_done)
+
+	needUnlock = false
+	unlockOSThread()
+
+	if isarchive || islibrary {
+		// A program compiled with -buildmode=c-archive or c-shared
+		// has a main, but it is not executed.
+		return
+	}
+	fn := main_main // make an indirect call, as the linker doesn't know the address of the main package when laying down the runtime
+	fn()
+	if raceenabled {
+		racefini()
+	}
+
+	// Make racy client program work: if panicking on
+	// another goroutine at the same time as main returns,
+	// let the other goroutine finish printing the panic trace.
+	// Once it does, it will exit. See issues 3934 and 20018.
+	if atomic.Load(&runningPanicDefers) != 0 {
+		// Running deferred functions should not take long.
+		for c := 0; c < 1000; c++ {
+			if atomic.Load(&runningPanicDefers) == 0 {
+				break
+			}
+			Gosched()
+		}
+	}
+	if atomic.Load(&panicking) != 0 {
+		gopark(nil, nil, waitReasonPanicWait, traceEvGoStop, 1)
+	}
+
+	exit(0)
+	for {
+		var x *int32
+		*x = 0
+	}
+}
+
+// os_beforeExit is called from os.Exit(0).
+//
+//go:linkname os_beforeExit os.runtime_beforeExit
+func os_beforeExit() {
+	if raceenabled {
+		racefini()
+	}
+}
+
+// start forcegc helper goroutine
+func init() {
+	go forcegchelper()
+}
+
+func forcegchelper() {
+	forcegc.g = getg()
+	lockInit(&forcegc.lock, lockRankForcegc)
+	for {
+		lock(&forcegc.lock)
+		if forcegc.idle != 0 {
+			throw("forcegc: phase error")
+		}
+		atomic.Store(&forcegc.idle, 1)
+		goparkunlock(&forcegc.lock, waitReasonForceGCIdle, traceEvGoBlock, 1)
+		// this goroutine is explicitly resumed by sysmon
+		if debug.gctrace > 0 {
+			println("GC forced")
+		}
+		// Time-triggered, fully concurrent.
+		gcStart(gcTrigger{kind: gcTriggerTime, now: nanotime()})
+	}
+}
+
+//go:nosplit
+
+// Gosched yields the processor, allowing other goroutines to run. It does not
+// suspend the current goroutine, so execution resumes automatically.
+func Gosched() {
+	checkTimeouts()
+	mcall(gosched_m)
+}
+
+// goschedguarded yields the processor like gosched, but also checks
+// for forbidden states and opts out of the yield in those cases.
+//
+//go:nosplit
+func goschedguarded() {
+	mcall(goschedguarded_m)
+}
+
+// Puts the current goroutine into a waiting state and calls unlockf on the
+// system stack.
+//
+// If unlockf returns false, the goroutine is resumed.
+//
+// unlockf must not access this G's stack, as it may be moved between
+// the call to gopark and the call to unlockf.
+//
+// Note that because unlockf is called after putting the G into a waiting
+// state, the G may have already been readied by the time unlockf is called
+// unless there is external synchronization preventing the G from being
+// readied. If unlockf returns false, it must guarantee that the G cannot be
+// externally readied.
+//
+// Reason explains why the goroutine has been parked. It is displayed in stack
+// traces and heap dumps. Reasons should be unique and descriptive. Do not
+// re-use reasons, add new ones.
+func gopark(unlockf func(*g, unsafe.Pointer) bool, lock unsafe.Pointer, reason waitReason, traceEv byte, traceskip int) {
+	if reason != waitReasonSleep {
+		checkTimeouts() // timeouts may expire while two goroutines keep the scheduler busy
+	}
+	mp := acquirem()
+	gp := mp.curg
+	status := readgstatus(gp)
+	if status != _Grunning && status != _Gscanrunning {
+		throw("gopark: bad g status")
+	}
+	mp.waitlock = lock
+	mp.waitunlockf = unlockf
+	gp.waitreason = reason
+	mp.waittraceev = traceEv
+	mp.waittraceskip = traceskip
+	releasem(mp)
+	// can't do anything that might move the G between Ms here.
+	mcall(park_m)
+}
+
+// Puts the current goroutine into a waiting state and unlocks the lock.
+// The goroutine can be made runnable again by calling goready(gp).
+func goparkunlock(lock *mutex, reason waitReason, traceEv byte, traceskip int) {
+	gopark(parkunlock_c, unsafe.Pointer(lock), reason, traceEv, traceskip)
+}
+
+func goready(gp *g, traceskip int) {
+	systemstack(func() {
+		ready(gp, traceskip, true)
+	})
+}
+
+//go:nosplit
+func acquireSudog() *sudog {
+	// Delicate dance: the semaphore implementation calls
+	// acquireSudog, acquireSudog calls new(sudog),
+	// new calls malloc, malloc can call the garbage collector,
+	// and the garbage collector calls the semaphore implementation
+	// in stopTheWorld.
+	// Break the cycle by doing acquirem/releasem around new(sudog).
+	// The acquirem/releasem increments m.locks during new(sudog),
+	// which keeps the garbage collector from being invoked.
+	mp := acquirem()
+	pp := mp.p.ptr()
+	if len(pp.sudogcache) == 0 {
+		lock(&sched.sudoglock)
+		// First, try to grab a batch from central cache.
+		for len(pp.sudogcache) < cap(pp.sudogcache)/2 && sched.sudogcache != nil {
+			s := sched.sudogcache
+			sched.sudogcache = s.next
+			s.next = nil
+			pp.sudogcache = append(pp.sudogcache, s)
+		}
+		unlock(&sched.sudoglock)
+		// If the central cache is empty, allocate a new one.
+		if len(pp.sudogcache) == 0 {
+			pp.sudogcache = append(pp.sudogcache, new(sudog))
+		}
+	}
+	n := len(pp.sudogcache)
+	s := pp.sudogcache[n-1]
+	pp.sudogcache[n-1] = nil
+	pp.sudogcache = pp.sudogcache[:n-1]
+	if s.elem != nil {
+		throw("acquireSudog: found s.elem != nil in cache")
+	}
+	releasem(mp)
+	return s
+}
+
+//go:nosplit
+func releaseSudog(s *sudog) {
+	if s.elem != nil {
+		throw("runtime: sudog with non-nil elem")
+	}
+	if s.isSelect {
+		throw("runtime: sudog with non-false isSelect")
+	}
+	if s.next != nil {
+		throw("runtime: sudog with non-nil next")
+	}
+	if s.prev != nil {
+		throw("runtime: sudog with non-nil prev")
+	}
+	if s.waitlink != nil {
+		throw("runtime: sudog with non-nil waitlink")
+	}
+	if s.c != nil {
+		throw("runtime: sudog with non-nil c")
+	}
+	gp := getg()
+	if gp.param != nil {
+		throw("runtime: releaseSudog with non-nil gp.param")
+	}
+	mp := acquirem() // avoid rescheduling to another P
+	pp := mp.p.ptr()
+	if len(pp.sudogcache) == cap(pp.sudogcache) {
+		// Transfer half of local cache to the central cache.
+		var first, last *sudog
+		for len(pp.sudogcache) > cap(pp.sudogcache)/2 {
+			n := len(pp.sudogcache)
+			p := pp.sudogcache[n-1]
+			pp.sudogcache[n-1] = nil
+			pp.sudogcache = pp.sudogcache[:n-1]
+			if first == nil {
+				first = p
+			} else {
+				last.next = p
+			}
+			last = p
+		}
+		lock(&sched.sudoglock)
+		last.next = sched.sudogcache
+		sched.sudogcache = first
+		unlock(&sched.sudoglock)
+	}
+	pp.sudogcache = append(pp.sudogcache, s)
+	releasem(mp)
+}
+
+// called from assembly
+func badmcall(fn func(*g)) {
+	throw("runtime: mcall called on m->g0 stack")
+}
+
+func badmcall2(fn func(*g)) {
+	throw("runtime: mcall function returned")
+}
+
+func badreflectcall() {
+	panic(plainError("arg size to reflect.call more than 1GB"))
+}
+
+var badmorestackg0Msg = "fatal: morestack on g0\n"
+
+//go:nosplit
+//go:nowritebarrierrec
+func badmorestackg0() {
+	sp := stringStructOf(&badmorestackg0Msg)
+	write(2, sp.str, int32(sp.len))
+}
+
+var badmorestackgsignalMsg = "fatal: morestack on gsignal\n"
+
+//go:nosplit
+//go:nowritebarrierrec
+func badmorestackgsignal() {
+	sp := stringStructOf(&badmorestackgsignalMsg)
+	write(2, sp.str, int32(sp.len))
+}
+
+//go:nosplit
+func badctxt() {
+	throw("ctxt != 0")
+}
+
+func lockedOSThread() bool {
+	gp := getg()
+	return gp.lockedm != 0 && gp.m.lockedg != 0
+}
+
+var (
+	// allgs contains all Gs ever created (including dead Gs), and thus
+	// never shrinks.
+	//
+	// Access via the slice is protected by allglock or stop-the-world.
+	// Readers that cannot take the lock may (carefully!) use the atomic
+	// variables below.
+	allglock mutex
+	allgs    []*g
+
+	// allglen and allgptr are atomic variables that contain len(allgs) and
+	// &allgs[0] respectively. Proper ordering depends on totally-ordered
+	// loads and stores. Writes are protected by allglock.
+	//
+	// allgptr is updated before allglen. Readers should read allglen
+	// before allgptr to ensure that allglen is always <= len(allgptr). New
+	// Gs appended during the race can be missed. For a consistent view of
+	// all Gs, allglock must be held.
+	//
+	// allgptr copies should always be stored as a concrete type or
+	// unsafe.Pointer, not uintptr, to ensure that GC can still reach it
+	// even if it points to a stale array.
+	allglen uintptr
+	allgptr **g
+)
+
+func allgadd(gp *g) {
+	if readgstatus(gp) == _Gidle {
+		throw("allgadd: bad status Gidle")
+	}
+
+	lock(&allglock)
+	allgs = append(allgs, gp)
+	if &allgs[0] != allgptr {
+		atomicstorep(unsafe.Pointer(&allgptr), unsafe.Pointer(&allgs[0]))
+	}
+	atomic.Storeuintptr(&allglen, uintptr(len(allgs)))
+	unlock(&allglock)
+}
+
+// allGsSnapshot returns a snapshot of the slice of all Gs.
+//
+// The world must be stopped or allglock must be held.
+func allGsSnapshot() []*g {
+	assertWorldStoppedOrLockHeld(&allglock)
+
+	// Because the world is stopped or allglock is held, allgadd
+	// cannot happen concurrently with this. allgs grows
+	// monotonically and existing entries never change, so we can
+	// simply return a copy of the slice header. For added safety,
+	// we trim everything past len because that can still change.
+	return allgs[:len(allgs):len(allgs)]
+}
+
+// atomicAllG returns &allgs[0] and len(allgs) for use with atomicAllGIndex.
+func atomicAllG() (**g, uintptr) {
+	length := atomic.Loaduintptr(&allglen)
+	ptr := (**g)(atomic.Loadp(unsafe.Pointer(&allgptr)))
+	return ptr, length
+}
+
+// atomicAllGIndex returns ptr[i] with the allgptr returned from atomicAllG.
+func atomicAllGIndex(ptr **g, i uintptr) *g {
+	return *(**g)(add(unsafe.Pointer(ptr), i*goarch.PtrSize))
+}
+
+// forEachG calls fn on every G from allgs.
+//
+// forEachG takes a lock to exclude concurrent addition of new Gs.
+func forEachG(fn func(gp *g)) {
+	lock(&allglock)
+	for _, gp := range allgs {
+		fn(gp)
+	}
+	unlock(&allglock)
+}
+
+// forEachGRace calls fn on every G from allgs.
+//
+// forEachGRace avoids locking, but does not exclude addition of new Gs during
+// execution, which may be missed.
+func forEachGRace(fn func(gp *g)) {
+	ptr, length := atomicAllG()
+	for i := uintptr(0); i < length; i++ {
+		gp := atomicAllGIndex(ptr, i)
+		fn(gp)
+	}
+	return
+}
+
+const (
+	// Number of goroutine ids to grab from sched.goidgen to local per-P cache at once.
+	// 16 seems to provide enough amortization, but other than that it's mostly arbitrary number.
+	_GoidCacheBatch = 16
+)
+
+// cpuinit extracts the environment variable GODEBUG from the environment on
+// Unix-like operating systems and calls internal/cpu.Initialize.
+func cpuinit() {
+	const prefix = "GODEBUG="
+	var env string
+
+	switch GOOS {
+	case "aix", "darwin", "ios", "dragonfly", "freebsd", "netbsd", "openbsd", "illumos", "solaris", "linux":
+		cpu.DebugOptions = true
+
+		// Similar to goenv_unix but extracts the environment value for
+		// GODEBUG directly.
+		// TODO(moehrmann): remove when general goenvs() can be called before cpuinit()
+		n := int32(0)
+		for argv_index(argv, argc+1+n) != nil {
+			n++
+		}
+
+		for i := int32(0); i < n; i++ {
+			p := argv_index(argv, argc+1+i)
+			s := *(*string)(unsafe.Pointer(&stringStruct{unsafe.Pointer(p), findnull(p)}))
+
+			if hasPrefix(s, prefix) {
+				env = gostring(p)[len(prefix):]
+				break
+			}
+		}
+	}
+
+	cpu.Initialize(env)
+
+	// Support cpu feature variables are used in code generated by the compiler
+	// to guard execution of instructions that can not be assumed to be always supported.
+	switch GOARCH {
+	case "386", "amd64":
+		x86HasPOPCNT = cpu.X86.HasPOPCNT
+		x86HasSSE41 = cpu.X86.HasSSE41
+		x86HasFMA = cpu.X86.HasFMA
+
+	case "arm":
+		armHasVFPv4 = cpu.ARM.HasVFPv4
+
+	case "arm64":
+		arm64HasATOMICS = cpu.ARM64.HasATOMICS
+	}
+}
+
+// The bootstrap sequence is:
+//
+//	call osinit
+//	call schedinit
+//	make & queue new G
+//	call runtime·mstart
+//
+// The new G calls runtime·main.
+func schedinit() {
+	lockInit(&sched.lock, lockRankSched)
+	lockInit(&sched.sysmonlock, lockRankSysmon)
+	lockInit(&sched.deferlock, lockRankDefer)
+	lockInit(&sched.sudoglock, lockRankSudog)
+	lockInit(&deadlock, lockRankDeadlock)
+	lockInit(&paniclk, lockRankPanic)
+	lockInit(&allglock, lockRankAllg)
+	lockInit(&allpLock, lockRankAllp)
+	lockInit(&reflectOffs.lock, lockRankReflectOffs)
+	lockInit(&finlock, lockRankFin)
+	lockInit(&trace.bufLock, lockRankTraceBuf)
+	lockInit(&trace.stringsLock, lockRankTraceStrings)
+	lockInit(&trace.lock, lockRankTrace)
+	lockInit(&cpuprof.lock, lockRankCpuprof)
+	lockInit(&trace.stackTab.lock, lockRankTraceStackTab)
+	// Enforce that this lock is always a leaf lock.
+	// All of this lock's critical sections should be
+	// extremely short.
+	lockInit(&memstats.heapStats.noPLock, lockRankLeafRank)
+
+	// raceinit must be the first call to race detector.
+	// In particular, it must be done before mallocinit below calls racemapshadow.
+	_g_ := getg()
+	if raceenabled {
+		_g_.racectx, raceprocctx0 = raceinit()
+	}
+
+	sched.maxmcount = 10000
+
+	// The world starts stopped.
+	worldStopped()
+
+	moduledataverify()
+	stackinit()
+	mallocinit()
+	cpuinit()      // must run before alginit
+	alginit()      // maps, hash, fastrand must not be used before this call
+	fastrandinit() // must run before mcommoninit
+	mcommoninit(_g_.m, -1)
+	modulesinit()   // provides activeModules
+	typelinksinit() // uses maps, activeModules
+	itabsinit()     // uses activeModules
+	stkobjinit()    // must run before GC starts
+
+	sigsave(&_g_.m.sigmask)
+	initSigmask = _g_.m.sigmask
+
+	if offset := unsafe.Offsetof(sched.timeToRun); offset%8 != 0 {
+		println(offset)
+		throw("sched.timeToRun not aligned to 8 bytes")
+	}
+
+	goargs()
+	goenvs()
+	parsedebugvars()
+	gcinit()
+
+	lock(&sched.lock)
+	sched.lastpoll = uint64(nanotime())
+	procs := ncpu
+	if n, ok := atoi32(gogetenv("GOMAXPROCS")); ok && n > 0 {
+		procs = n
+	}
+	if procresize(procs) != nil {
+		throw("unknown runnable goroutine during bootstrap")
+	}
+	unlock(&sched.lock)
+
+	// World is effectively started now, as P's can run.
+	worldStarted()
+
+	// For cgocheck > 1, we turn on the write barrier at all times
+	// and check all pointer writes. We can't do this until after
+	// procresize because the write barrier needs a P.
+	if debug.cgocheck > 1 {
+		writeBarrier.cgo = true
+		writeBarrier.enabled = true
+		for _, p := range allp {
+			p.wbBuf.reset()
+		}
+	}
+
+	if buildVersion == "" {
+		// Condition should never trigger. This code just serves
+		// to ensure runtime·buildVersion is kept in the resulting binary.
+		buildVersion = "unknown"
+	}
+	if len(modinfo) == 1 {
+		// Condition should never trigger. This code just serves
+		// to ensure runtime·modinfo is kept in the resulting binary.
+		modinfo = ""
+	}
+}
+
+func dumpgstatus(gp *g) {
+	_g_ := getg()
+	print("runtime: gp: gp=", gp, ", goid=", gp.goid, ", gp->atomicstatus=", readgstatus(gp), "\n")
+	print("runtime:  g:  g=", _g_, ", goid=", _g_.goid, ",  g->atomicstatus=", readgstatus(_g_), "\n")
+}
+
+// sched.lock must be held.
+func checkmcount() {
+	assertLockHeld(&sched.lock)
+
+	if mcount() > sched.maxmcount {
+		print("runtime: program exceeds ", sched.maxmcount, "-thread limit\n")
+		throw("thread exhaustion")
+	}
+}
+
+// mReserveID returns the next ID to use for a new m. This new m is immediately
+// considered 'running' by checkdead.
+//
+// sched.lock must be held.
+func mReserveID() int64 {
+	assertLockHeld(&sched.lock)
+
+	if sched.mnext+1 < sched.mnext {
+		throw("runtime: thread ID overflow")
+	}
+	id := sched.mnext
+	sched.mnext++
+	checkmcount()
+	return id
+}
+
+// Pre-allocated ID may be passed as 'id', or omitted by passing -1.
+func mcommoninit(mp *m, id int64) {
+	_g_ := getg()
+
+	// g0 stack won't make sense for user (and is not necessary unwindable).
+	if _g_ != _g_.m.g0 {
+		callers(1, mp.createstack[:])
+	}
+
+	lock(&sched.lock)
+
+	if id >= 0 {
+		mp.id = id
+	} else {
+		mp.id = mReserveID()
+	}
+
+	lo := uint32(int64Hash(uint64(mp.id), fastrandseed))
+	hi := uint32(int64Hash(uint64(cputicks()), ^fastrandseed))
+	if lo|hi == 0 {
+		hi = 1
+	}
+	// Same behavior as for 1.17.
+	// TODO: Simplify ths.
+	if goarch.BigEndian {
+		mp.fastrand = uint64(lo)<<32 | uint64(hi)
+	} else {
+		mp.fastrand = uint64(hi)<<32 | uint64(lo)
+	}
+
+	mpreinit(mp)
+	if mp.gsignal != nil {
+		mp.gsignal.stackguard1 = mp.gsignal.stack.lo + _StackGuard
+	}
+
+	// Add to allm so garbage collector doesn't free g->m
+	// when it is just in a register or thread-local storage.
+	mp.alllink = allm
+
+	// NumCgoCall() iterates over allm w/o schedlock,
+	// so we need to publish it safely.
+	atomicstorep(unsafe.Pointer(&allm), unsafe.Pointer(mp))
+	unlock(&sched.lock)
+
+	// Allocate memory to hold a cgo traceback if the cgo call crashes.
+	if iscgo || GOOS == "solaris" || GOOS == "illumos" || GOOS == "windows" {
+		mp.cgoCallers = new(cgoCallers)
+	}
+}
+
+var fastrandseed uintptr
+
+func fastrandinit() {
+	s := (*[unsafe.Sizeof(fastrandseed)]byte)(unsafe.Pointer(&fastrandseed))[:]
+	getRandomData(s)
+}
+
+// Mark gp ready to run.
+func ready(gp *g, traceskip int, next bool) {
+	if trace.enabled {
+		traceGoUnpark(gp, traceskip)
+	}
+
+	status := readgstatus(gp)
+
+	// Mark runnable.
+	_g_ := getg()
+	mp := acquirem() // disable preemption because it can be holding p in a local var
+	if status&^_Gscan != _Gwaiting {
+		dumpgstatus(gp)
+		throw("bad g->status in ready")
+	}
+
+	// status is Gwaiting or Gscanwaiting, make Grunnable and put on runq
+	casgstatus(gp, _Gwaiting, _Grunnable)
+	runqput(_g_.m.p.ptr(), gp, next)
+	wakep()
+	releasem(mp)
+}
+
+// freezeStopWait is a large value that freezetheworld sets
+// sched.stopwait to in order to request that all Gs permanently stop.
+const freezeStopWait = 0x7fffffff
+
+// freezing is set to non-zero if the runtime is trying to freeze the
+// world.
+var freezing uint32
+
+// Similar to stopTheWorld but best-effort and can be called several times.
+// There is no reverse operation, used during crashing.
+// This function must not lock any mutexes.
+func freezetheworld() {
+	atomic.Store(&freezing, 1)
+	// stopwait and preemption requests can be lost
+	// due to races with concurrently executing threads,
+	// so try several times
+	for i := 0; i < 5; i++ {
+		// this should tell the scheduler to not start any new goroutines
+		sched.stopwait = freezeStopWait
+		atomic.Store(&sched.gcwaiting, 1)
+		// this should stop running goroutines
+		if !preemptall() {
+			break // no running goroutines
+		}
+		usleep(1000)
+	}
+	// to be sure
+	usleep(1000)
+	preemptall()
+	usleep(1000)
+}
+
+// All reads and writes of g's status go through readgstatus, casgstatus
+// castogscanstatus, casfrom_Gscanstatus.
+//
+//go:nosplit
+func readgstatus(gp *g) uint32 {
+	return atomic.Load(&gp.atomicstatus)
+}
+
+// The Gscanstatuses are acting like locks and this releases them.
+// If it proves to be a performance hit we should be able to make these
+// simple atomic stores but for now we are going to throw if
+// we see an inconsistent state.
+func casfrom_Gscanstatus(gp *g, oldval, newval uint32) {
+	success := false
+
+	// Check that transition is valid.
+	switch oldval {
+	default:
+		print("runtime: casfrom_Gscanstatus bad oldval gp=", gp, ", oldval=", hex(oldval), ", newval=", hex(newval), "\n")
+		dumpgstatus(gp)
+		throw("casfrom_Gscanstatus:top gp->status is not in scan state")
+	case _Gscanrunnable,
+		_Gscanwaiting,
+		_Gscanrunning,
+		_Gscansyscall,
+		_Gscanpreempted:
+		if newval == oldval&^_Gscan {
+			success = atomic.Cas(&gp.atomicstatus, oldval, newval)
+		}
+	}
+	if !success {
+		print("runtime: casfrom_Gscanstatus failed gp=", gp, ", oldval=", hex(oldval), ", newval=", hex(newval), "\n")
+		dumpgstatus(gp)
+		throw("casfrom_Gscanstatus: gp->status is not in scan state")
+	}
+	releaseLockRank(lockRankGscan)
+}
+
+// This will return false if the gp is not in the expected status and the cas fails.
+// This acts like a lock acquire while the casfromgstatus acts like a lock release.
+func castogscanstatus(gp *g, oldval, newval uint32) bool {
+	switch oldval {
+	case _Grunnable,
+		_Grunning,
+		_Gwaiting,
+		_Gsyscall:
+		if newval == oldval|_Gscan {
+			r := atomic.Cas(&gp.atomicstatus, oldval, newval)
+			if r {
+				acquireLockRank(lockRankGscan)
+			}
+			return r
+
+		}
+	}
+	print("runtime: castogscanstatus oldval=", hex(oldval), " newval=", hex(newval), "\n")
+	throw("castogscanstatus")
+	panic("not reached")
+}
+
+// If asked to move to or from a Gscanstatus this will throw. Use the castogscanstatus
+// and casfrom_Gscanstatus instead.
+// casgstatus will loop if the g->atomicstatus is in a Gscan status until the routine that
+// put it in the Gscan state is finished.
+//
+//go:nosplit
+func casgstatus(gp *g, oldval, newval uint32) {
+	if (oldval&_Gscan != 0) || (newval&_Gscan != 0) || oldval == newval {
+		systemstack(func() {
+			print("runtime: casgstatus: oldval=", hex(oldval), " newval=", hex(newval), "\n")
+			throw("casgstatus: bad incoming values")
+		})
+	}
+
+	acquireLockRank(lockRankGscan)
+	releaseLockRank(lockRankGscan)
+
+	// See https://golang.org/cl/21503 for justification of the yield delay.
+	const yieldDelay = 5 * 1000
+	var nextYield int64
+
+	// loop if gp->atomicstatus is in a scan state giving
+	// GC time to finish and change the state to oldval.
+	for i := 0; !atomic.Cas(&gp.atomicstatus, oldval, newval); i++ {
+		if oldval == _Gwaiting && gp.atomicstatus == _Grunnable {
+			throw("casgstatus: waiting for Gwaiting but is Grunnable")
+		}
+		if i == 0 {
+			nextYield = nanotime() + yieldDelay
+		}
+		if nanotime() < nextYield {
+			for x := 0; x < 10 && gp.atomicstatus != oldval; x++ {
+				procyield(1)
+			}
+		} else {
+			osyield()
+			nextYield = nanotime() + yieldDelay/2
+		}
+	}
+
+	// Handle tracking for scheduling latencies.
+	if oldval == _Grunning {
+		// Track every 8th time a goroutine transitions out of running.
+		if gp.trackingSeq%gTrackingPeriod == 0 {
+			gp.tracking = true
+		}
+		gp.trackingSeq++
+	}
+	if gp.tracking {
+		if oldval == _Grunnable {
+			// We transitioned out of runnable, so measure how much
+			// time we spent in this state and add it to
+			// runnableTime.
+			now := nanotime()
+			gp.runnableTime += now - gp.runnableStamp
+			gp.runnableStamp = 0
+		}
+		if newval == _Grunnable {
+			// We just transitioned into runnable, so record what
+			// time that happened.
+			now := nanotime()
+			gp.runnableStamp = now
+		} else if newval == _Grunning {
+			// We're transitioning into running, so turn off
+			// tracking and record how much time we spent in
+			// runnable.
+			gp.tracking = false
+			sched.timeToRun.record(gp.runnableTime)
+			gp.runnableTime = 0
+		}
+	}
+}
+
+// casgstatus(gp, oldstatus, Gcopystack), assuming oldstatus is Gwaiting or Grunnable.
+// Returns old status. Cannot call casgstatus directly, because we are racing with an
+// async wakeup that might come in from netpoll. If we see Gwaiting from the readgstatus,
+// it might have become Grunnable by the time we get to the cas. If we called casgstatus,
+// it would loop waiting for the status to go back to Gwaiting, which it never will.
+//
+//go:nosplit
+func casgcopystack(gp *g) uint32 {
+	for {
+		oldstatus := readgstatus(gp) &^ _Gscan
+		if oldstatus != _Gwaiting && oldstatus != _Grunnable {
+			throw("copystack: bad status, not Gwaiting or Grunnable")
+		}
+		if atomic.Cas(&gp.atomicstatus, oldstatus, _Gcopystack) {
+			return oldstatus
+		}
+	}
+}
+
+// casGToPreemptScan transitions gp from _Grunning to _Gscan|_Gpreempted.
+//
+// TODO(austin): This is the only status operation that both changes
+// the status and locks the _Gscan bit. Rethink this.
+func casGToPreemptScan(gp *g, old, new uint32) {
+	if old != _Grunning || new != _Gscan|_Gpreempted {
+		throw("bad g transition")
+	}
+	acquireLockRank(lockRankGscan)
+	for !atomic.Cas(&gp.atomicstatus, _Grunning, _Gscan|_Gpreempted) {
+	}
+}
+
+// casGFromPreempted attempts to transition gp from _Gpreempted to
+// _Gwaiting. If successful, the caller is responsible for
+// re-scheduling gp.
+func casGFromPreempted(gp *g, old, new uint32) bool {
+	if old != _Gpreempted || new != _Gwaiting {
+		throw("bad g transition")
+	}
+	return atomic.Cas(&gp.atomicstatus, _Gpreempted, _Gwaiting)
+}
+
+// stopTheWorld stops all P's from executing goroutines, interrupting
+// all goroutines at GC safe points and records reason as the reason
+// for the stop. On return, only the current goroutine's P is running.
+// stopTheWorld must not be called from a system stack and the caller
+// must not hold worldsema. The caller must call startTheWorld when
+// other P's should resume execution.
+//
+// stopTheWorld is safe for multiple goroutines to call at the
+// same time. Each will execute its own stop, and the stops will
+// be serialized.
+//
+// This is also used by routines that do stack dumps. If the system is
+// in panic or being exited, this may not reliably stop all
+// goroutines.
+func stopTheWorld(reason string) {
+	semacquire(&worldsema)
+	gp := getg()
+	gp.m.preemptoff = reason
+	systemstack(func() {
+		// Mark the goroutine which called stopTheWorld preemptible so its
+		// stack may be scanned.
+		// This lets a mark worker scan us while we try to stop the world
+		// since otherwise we could get in a mutual preemption deadlock.
+		// We must not modify anything on the G stack because a stack shrink
+		// may occur. A stack shrink is otherwise OK though because in order
+		// to return from this function (and to leave the system stack) we
+		// must have preempted all goroutines, including any attempting
+		// to scan our stack, in which case, any stack shrinking will
+		// have already completed by the time we exit.
+		casgstatus(gp, _Grunning, _Gwaiting)
+		stopTheWorldWithSema()
+		casgstatus(gp, _Gwaiting, _Grunning)
+	})
+}
+
+// startTheWorld undoes the effects of stopTheWorld.
+func startTheWorld() {
+	systemstack(func() { startTheWorldWithSema(false) })
+
+	// worldsema must be held over startTheWorldWithSema to ensure
+	// gomaxprocs cannot change while worldsema is held.
+	//
+	// Release worldsema with direct handoff to the next waiter, but
+	// acquirem so that semrelease1 doesn't try to yield our time.
+	//
+	// Otherwise if e.g. ReadMemStats is being called in a loop,
+	// it might stomp on other attempts to stop the world, such as
+	// for starting or ending GC. The operation this blocks is
+	// so heavy-weight that we should just try to be as fair as
+	// possible here.
+	//
+	// We don't want to just allow us to get preempted between now
+	// and releasing the semaphore because then we keep everyone
+	// (including, for example, GCs) waiting longer.
+	mp := acquirem()
+	mp.preemptoff = ""
+	semrelease1(&worldsema, true, 0)
+	releasem(mp)
+}
+
+// stopTheWorldGC has the same effect as stopTheWorld, but blocks
+// until the GC is not running. It also blocks a GC from starting
+// until startTheWorldGC is called.
+func stopTheWorldGC(reason string) {
+	semacquire(&gcsema)
+	stopTheWorld(reason)
+}
+
+// startTheWorldGC undoes the effects of stopTheWorldGC.
+func startTheWorldGC() {
+	startTheWorld()
+	semrelease(&gcsema)
+}
+
+// Holding worldsema grants an M the right to try to stop the world.
+var worldsema uint32 = 1
+
+// Holding gcsema grants the M the right to block a GC, and blocks
+// until the current GC is done. In particular, it prevents gomaxprocs
+// from changing concurrently.
+//
+// TODO(mknyszek): Once gomaxprocs and the execution tracer can handle
+// being changed/enabled during a GC, remove this.
+var gcsema uint32 = 1
+
+// stopTheWorldWithSema is the core implementation of stopTheWorld.
+// The caller is responsible for acquiring worldsema and disabling
+// preemption first and then should stopTheWorldWithSema on the system
+// stack:
+//
+//	semacquire(&worldsema, 0)
+//	m.preemptoff = "reason"
+//	systemstack(stopTheWorldWithSema)
+//
+// When finished, the caller must either call startTheWorld or undo
+// these three operations separately:
+//
+//	m.preemptoff = ""
+//	systemstack(startTheWorldWithSema)
+//	semrelease(&worldsema)
+//
+// It is allowed to acquire worldsema once and then execute multiple
+// startTheWorldWithSema/stopTheWorldWithSema pairs.
+// Other P's are able to execute between successive calls to
+// startTheWorldWithSema and stopTheWorldWithSema.
+// Holding worldsema causes any other goroutines invoking
+// stopTheWorld to block.
+func stopTheWorldWithSema() {
+	_g_ := getg()
+
+	// If we hold a lock, then we won't be able to stop another M
+	// that is blocked trying to acquire the lock.
+	if _g_.m.locks > 0 {
+		throw("stopTheWorld: holding locks")
+	}
+
+	lock(&sched.lock)
+	sched.stopwait = gomaxprocs
+	atomic.Store(&sched.gcwaiting, 1)
+	preemptall()
+	// stop current P
+	_g_.m.p.ptr().status = _Pgcstop // Pgcstop is only diagnostic.
+	sched.stopwait--
+	// try to retake all P's in Psyscall status
+	for _, p := range allp {
+		s := p.status
+		if s == _Psyscall && atomic.Cas(&p.status, s, _Pgcstop) {
+			if trace.enabled {
+				traceGoSysBlock(p)
+				traceProcStop(p)
+			}
+			p.syscalltick++
+			sched.stopwait--
+		}
+	}
+	// stop idle P's
+	now := nanotime()
+	for {
+		p, _ := pidleget(now)
+		if p == nil {
+			break
+		}
+		p.status = _Pgcstop
+		sched.stopwait--
+	}
+	wait := sched.stopwait > 0
+	unlock(&sched.lock)
+
+	// wait for remaining P's to stop voluntarily
+	if wait {
+		for {
+			// wait for 100us, then try to re-preempt in case of any races
+			if notetsleep(&sched.stopnote, 100*1000) {
+				noteclear(&sched.stopnote)
+				break
+			}
+			preemptall()
+		}
+	}
+
+	// sanity checks
+	bad := ""
+	if sched.stopwait != 0 {
+		bad = "stopTheWorld: not stopped (stopwait != 0)"
+	} else {
+		for _, p := range allp {
+			if p.status != _Pgcstop {
+				bad = "stopTheWorld: not stopped (status != _Pgcstop)"
+			}
+		}
+	}
+	if atomic.Load(&freezing) != 0 {
+		// Some other thread is panicking. This can cause the
+		// sanity checks above to fail if the panic happens in
+		// the signal handler on a stopped thread. Either way,
+		// we should halt this thread.
+		lock(&deadlock)
+		lock(&deadlock)
+	}
+	if bad != "" {
+		throw(bad)
+	}
+
+	worldStopped()
+}
+
+func startTheWorldWithSema(emitTraceEvent bool) int64 {
+	assertWorldStopped()
+
+	mp := acquirem() // disable preemption because it can be holding p in a local var
+	if netpollinited() {
+		list := netpoll(0) // non-blocking
+		injectglist(&list)
+	}
+	lock(&sched.lock)
+
+	procs := gomaxprocs
+	if newprocs != 0 {
+		procs = newprocs
+		newprocs = 0
+	}
+	p1 := procresize(procs)
+	sched.gcwaiting = 0
+	if sched.sysmonwait != 0 {
+		sched.sysmonwait = 0
+		notewakeup(&sched.sysmonnote)
+	}
+	unlock(&sched.lock)
+
+	worldStarted()
+
+	for p1 != nil {
+		p := p1
+		p1 = p1.link.ptr()
+		if p.m != 0 {
+			mp := p.m.ptr()
+			p.m = 0
+			if mp.nextp != 0 {
+				throw("startTheWorld: inconsistent mp->nextp")
+			}
+			mp.nextp.set(p)
+			notewakeup(&mp.park)
+		} else {
+			// Start M to run P.  Do not start another M below.
+			newm(nil, p, -1)
+		}
+	}
+
+	// Capture start-the-world time before doing clean-up tasks.
+	startTime := nanotime()
+	if emitTraceEvent {
+		traceGCSTWDone()
+	}
+
+	// Wakeup an additional proc in case we have excessive runnable goroutines
+	// in local queues or in the global queue. If we don't, the proc will park itself.
+	// If we have lots of excessive work, resetspinning will unpark additional procs as necessary.
+	wakep()
+
+	releasem(mp)
+
+	return startTime
+}
+
+// usesLibcall indicates whether this runtime performs system calls
+// via libcall.
+func usesLibcall() bool {
+	switch GOOS {
+	case "aix", "darwin", "illumos", "ios", "solaris", "windows":
+		return true
+	case "openbsd":
+		return GOARCH == "386" || GOARCH == "amd64" || GOARCH == "arm" || GOARCH == "arm64"
+	}
+	return false
+}
+
+// mStackIsSystemAllocated indicates whether this runtime starts on a
+// system-allocated stack.
+func mStackIsSystemAllocated() bool {
+	switch GOOS {
+	case "aix", "darwin", "plan9", "illumos", "ios", "solaris", "windows":
+		return true
+	case "openbsd":
+		switch GOARCH {
+		case "386", "amd64", "arm", "arm64":
+			return true
+		}
+	}
+	return false
+}
+
+// mstart is the entry-point for new Ms.
+// It is written in assembly, uses ABI0, is marked TOPFRAME, and calls mstart0.
+func mstart()
+
+// mstart0 is the Go entry-point for new Ms.
+// This must not split the stack because we may not even have stack
+// bounds set up yet.
+//
+// May run during STW (because it doesn't have a P yet), so write
+// barriers are not allowed.
+//
+//go:nosplit
+//go:nowritebarrierrec
+func mstart0() {
+	_g_ := getg()
+
+	osStack := _g_.stack.lo == 0
+	if osStack {
+		// Initialize stack bounds from system stack.
+		// Cgo may have left stack size in stack.hi.
+		// minit may update the stack bounds.
+		//
+		// Note: these bounds may not be very accurate.
+		// We set hi to &size, but there are things above
+		// it. The 1024 is supposed to compensate this,
+		// but is somewhat arbitrary.
+		size := _g_.stack.hi
+		if size == 0 {
+			size = 8192 * sys.StackGuardMultiplier
+		}
+		_g_.stack.hi = uintptr(noescape(unsafe.Pointer(&size)))
+		_g_.stack.lo = _g_.stack.hi - size + 1024
+	}
+	// Initialize stack guard so that we can start calling regular
+	// Go code.
+	_g_.stackguard0 = _g_.stack.lo + _StackGuard
+	// This is the g0, so we can also call go:systemstack
+	// functions, which check stackguard1.
+	_g_.stackguard1 = _g_.stackguard0
+	mstart1()
+
+	// Exit this thread.
+	if mStackIsSystemAllocated() {
+		// Windows, Solaris, illumos, Darwin, AIX and Plan 9 always system-allocate
+		// the stack, but put it in _g_.stack before mstart,
+		// so the logic above hasn't set osStack yet.
+		osStack = true
+	}
+	mexit(osStack)
+}
+
+// The go:noinline is to guarantee the getcallerpc/getcallersp below are safe,
+// so that we can set up g0.sched to return to the call of mstart1 above.
+//
+//go:noinline
+func mstart1() {
+	_g_ := getg()
+
+	if _g_ != _g_.m.g0 {
+		throw("bad runtime·mstart")
+	}
+
+	// Set up m.g0.sched as a label returning to just
+	// after the mstart1 call in mstart0 above, for use by goexit0 and mcall.
+	// We're never coming back to mstart1 after we call schedule,
+	// so other calls can reuse the current frame.
+	// And goexit0 does a gogo that needs to return from mstart1
+	// and let mstart0 exit the thread.
+	_g_.sched.g = guintptr(unsafe.Pointer(_g_))
+	_g_.sched.pc = getcallerpc()
+	_g_.sched.sp = getcallersp()
+
+	asminit()
+	minit()
+
+	// Install signal handlers; after minit so that minit can
+	// prepare the thread to be able to handle the signals.
+	if _g_.m == &m0 {
+		mstartm0()
+	}
+
+	if fn := _g_.m.mstartfn; fn != nil {
+		fn()
+	}
+
+	if _g_.m != &m0 {
+		acquirep(_g_.m.nextp.ptr())
+		_g_.m.nextp = 0
+	}
+	schedule()
+}
+
+// mstartm0 implements part of mstart1 that only runs on the m0.
+//
+// Write barriers are allowed here because we know the GC can't be
+// running yet, so they'll be no-ops.
+//
+//go:yeswritebarrierrec
+func mstartm0() {
+	// Create an extra M for callbacks on threads not created by Go.
+	// An extra M is also needed on Windows for callbacks created by
+	// syscall.NewCallback. See issue #6751 for details.
+	if (iscgo || GOOS == "windows") && !cgoHasExtraM {
+		cgoHasExtraM = true
+		newextram()
+	}
+	initsig(false)
+}
+
+// mPark causes a thread to park itself, returning once woken.
+//
+//go:nosplit
+func mPark() {
+	gp := getg()
+	notesleep(&gp.m.park)
+	noteclear(&gp.m.park)
+}
+
+// mexit tears down and exits the current thread.
+//
+// Don't call this directly to exit the thread, since it must run at
+// the top of the thread stack. Instead, use gogo(&_g_.m.g0.sched) to
+// unwind the stack to the point that exits the thread.
+//
+// It is entered with m.p != nil, so write barriers are allowed. It
+// will release the P before exiting.
+//
+//go:yeswritebarrierrec
+func mexit(osStack bool) {
+	g := getg()
+	m := g.m
+
+	if m == &m0 {
+		// This is the main thread. Just wedge it.
+		//
+		// On Linux, exiting the main thread puts the process
+		// into a non-waitable zombie state. On Plan 9,
+		// exiting the main thread unblocks wait even though
+		// other threads are still running. On Solaris we can
+		// neither exitThread nor return from mstart. Other
+		// bad things probably happen on other platforms.
+		//
+		// We could try to clean up this M more before wedging
+		// it, but that complicates signal handling.
+		handoffp(releasep())
+		lock(&sched.lock)
+		sched.nmfreed++
+		checkdead()
+		unlock(&sched.lock)
+		mPark()
+		throw("locked m0 woke up")
+	}
+
+	sigblock(true)
+	unminit()
+
+	// Free the gsignal stack.
+	if m.gsignal != nil {
+		stackfree(m.gsignal.stack)
+		// On some platforms, when calling into VDSO (e.g. nanotime)
+		// we store our g on the gsignal stack, if there is one.
+		// Now the stack is freed, unlink it from the m, so we
+		// won't write to it when calling VDSO code.
+		m.gsignal = nil
+	}
+
+	// Remove m from allm.
+	lock(&sched.lock)
+	for pprev := &allm; *pprev != nil; pprev = &(*pprev).alllink {
+		if *pprev == m {
+			*pprev = m.alllink
+			goto found
+		}
+	}
+	throw("m not found in allm")
+found:
+	if !osStack {
+		// Delay reaping m until it's done with the stack.
+		//
+		// If this is using an OS stack, the OS will free it
+		// so there's no need for reaping.
+		atomic.Store(&m.freeWait, 1)
+		// Put m on the free list, though it will not be reaped until
+		// freeWait is 0. Note that the free list must not be linked
+		// through alllink because some functions walk allm without
+		// locking, so may be using alllink.
+		m.freelink = sched.freem
+		sched.freem = m
+	}
+	unlock(&sched.lock)
+
+	atomic.Xadd64(&ncgocall, int64(m.ncgocall))
+
+	// Release the P.
+	handoffp(releasep())
+	// After this point we must not have write barriers.
+
+	// Invoke the deadlock detector. This must happen after
+	// handoffp because it may have started a new M to take our
+	// P's work.
+	lock(&sched.lock)
+	sched.nmfreed++
+	checkdead()
+	unlock(&sched.lock)
+
+	if GOOS == "darwin" || GOOS == "ios" {
+		// Make sure pendingPreemptSignals is correct when an M exits.
+		// For #41702.
+		if atomic.Load(&m.signalPending) != 0 {
+			atomic.Xadd(&pendingPreemptSignals, -1)
+		}
+	}
+
+	// Destroy all allocated resources. After this is called, we may no
+	// longer take any locks.
+	mdestroy(m)
+
+	if osStack {
+		// Return from mstart and let the system thread
+		// library free the g0 stack and terminate the thread.
+		return
+	}
+
+	// mstart is the thread's entry point, so there's nothing to
+	// return to. Exit the thread directly. exitThread will clear
+	// m.freeWait when it's done with the stack and the m can be
+	// reaped.
+	exitThread(&m.freeWait)
+}
+
+// forEachP calls fn(p) for every P p when p reaches a GC safe point.
+// If a P is currently executing code, this will bring the P to a GC
+// safe point and execute fn on that P. If the P is not executing code
+// (it is idle or in a syscall), this will call fn(p) directly while
+// preventing the P from exiting its state. This does not ensure that
+// fn will run on every CPU executing Go code, but it acts as a global
+// memory barrier. GC uses this as a "ragged barrier."
+//
+// The caller must hold worldsema.
+//
+//go:systemstack
+func forEachP(fn func(*p)) {
+	mp := acquirem()
+	_p_ := getg().m.p.ptr()
+
+	lock(&sched.lock)
+	if sched.safePointWait != 0 {
+		throw("forEachP: sched.safePointWait != 0")
+	}
+	sched.safePointWait = gomaxprocs - 1
+	sched.safePointFn = fn
+
+	// Ask all Ps to run the safe point function.
+	for _, p := range allp {
+		if p != _p_ {
+			atomic.Store(&p.runSafePointFn, 1)
+		}
+	}
+	preemptall()
+
+	// Any P entering _Pidle or _Psyscall from now on will observe
+	// p.runSafePointFn == 1 and will call runSafePointFn when
+	// changing its status to _Pidle/_Psyscall.
+
+	// Run safe point function for all idle Ps. sched.pidle will
+	// not change because we hold sched.lock.
+	for p := sched.pidle.ptr(); p != nil; p = p.link.ptr() {
+		if atomic.Cas(&p.runSafePointFn, 1, 0) {
+			fn(p)
+			sched.safePointWait--
+		}
+	}
+
+	wait := sched.safePointWait > 0
+	unlock(&sched.lock)
+
+	// Run fn for the current P.
+	fn(_p_)
+
+	// Force Ps currently in _Psyscall into _Pidle and hand them
+	// off to induce safe point function execution.
+	for _, p := range allp {
+		s := p.status
+		if s == _Psyscall && p.runSafePointFn == 1 && atomic.Cas(&p.status, s, _Pidle) {
+			if trace.enabled {
+				traceGoSysBlock(p)
+				traceProcStop(p)
+			}
+			p.syscalltick++
+			handoffp(p)
+		}
+	}
+
+	// Wait for remaining Ps to run fn.
+	if wait {
+		for {
+			// Wait for 100us, then try to re-preempt in
+			// case of any races.
+			//
+			// Requires system stack.
+			if notetsleep(&sched.safePointNote, 100*1000) {
+				noteclear(&sched.safePointNote)
+				break
+			}
+			preemptall()
+		}
+	}
+	if sched.safePointWait != 0 {
+		throw("forEachP: not done")
+	}
+	for _, p := range allp {
+		if p.runSafePointFn != 0 {
+			throw("forEachP: P did not run fn")
+		}
+	}
+
+	lock(&sched.lock)
+	sched.safePointFn = nil
+	unlock(&sched.lock)
+	releasem(mp)
+}
+
+// runSafePointFn runs the safe point function, if any, for this P.
+// This should be called like
+//
+//	if getg().m.p.runSafePointFn != 0 {
+//	    runSafePointFn()
+//	}
+//
+// runSafePointFn must be checked on any transition in to _Pidle or
+// _Psyscall to avoid a race where forEachP sees that the P is running
+// just before the P goes into _Pidle/_Psyscall and neither forEachP
+// nor the P run the safe-point function.
+func runSafePointFn() {
+	p := getg().m.p.ptr()
+	// Resolve the race between forEachP running the safe-point
+	// function on this P's behalf and this P running the
+	// safe-point function directly.
+	if !atomic.Cas(&p.runSafePointFn, 1, 0) {
+		return
+	}
+	sched.safePointFn(p)
+	lock(&sched.lock)
+	sched.safePointWait--
+	if sched.safePointWait == 0 {
+		notewakeup(&sched.safePointNote)
+	}
+	unlock(&sched.lock)
+}
+
+// When running with cgo, we call _cgo_thread_start
+// to start threads for us so that we can play nicely with
+// foreign code.
+var cgoThreadStart unsafe.Pointer
+
+type cgothreadstart struct {
+	g   guintptr
+	tls *uint64
+	fn  unsafe.Pointer
+}
+
+// Allocate a new m unassociated with any thread.
+// Can use p for allocation context if needed.
+// fn is recorded as the new m's m.mstartfn.
+// id is optional pre-allocated m ID. Omit by passing -1.
+//
+// This function is allowed to have write barriers even if the caller
+// isn't because it borrows _p_.
+//
+//go:yeswritebarrierrec
+func allocm(_p_ *p, fn func(), id int64) *m {
+	allocmLock.rlock()
+
+	// The caller owns _p_, but we may borrow (i.e., acquirep) it. We must
+	// disable preemption to ensure it is not stolen, which would make the
+	// caller lose ownership.
+	acquirem()
+
+	_g_ := getg()
+	if _g_.m.p == 0 {
+		acquirep(_p_) // temporarily borrow p for mallocs in this function
+	}
+
+	// Release the free M list. We need to do this somewhere and
+	// this may free up a stack we can use.
+	if sched.freem != nil {
+		lock(&sched.lock)
+		var newList *m
+		for freem := sched.freem; freem != nil; {
+			if freem.freeWait != 0 {
+				next := freem.freelink
+				freem.freelink = newList
+				newList = freem
+				freem = next
+				continue
+			}
+			// stackfree must be on the system stack, but allocm is
+			// reachable off the system stack transitively from
+			// startm.
+			systemstack(func() {
+				stackfree(freem.g0.stack)
+			})
+			freem = freem.freelink
+		}
+		sched.freem = newList
+		unlock(&sched.lock)
+	}
+
+	mp := new(m)
+	mp.mstartfn = fn
+	mcommoninit(mp, id)
+
+	// In case of cgo or Solaris or illumos or Darwin, pthread_create will make us a stack.
+	// Windows and Plan 9 will layout sched stack on OS stack.
+	if iscgo || mStackIsSystemAllocated() {
+		mp.g0 = malg(-1)
+	} else {
+		mp.g0 = malg(8192 * sys.StackGuardMultiplier)
+	}
+	mp.g0.m = mp
+
+	if _p_ == _g_.m.p.ptr() {
+		releasep()
+	}
+
+	releasem(_g_.m)
+	allocmLock.runlock()
+	return mp
+}
+
+// needm is called when a cgo callback happens on a
+// thread without an m (a thread not created by Go).
+// In this case, needm is expected to find an m to use
+// and return with m, g initialized correctly.
+// Since m and g are not set now (likely nil, but see below)
+// needm is limited in what routines it can call. In particular
+// it can only call nosplit functions (textflag 7) and cannot
+// do any scheduling that requires an m.
+//
+// In order to avoid needing heavy lifting here, we adopt
+// the following strategy: there is a stack of available m's
+// that can be stolen. Using compare-and-swap
+// to pop from the stack has ABA races, so we simulate
+// a lock by doing an exchange (via Casuintptr) to steal the stack
+// head and replace the top pointer with MLOCKED (1).
+// This serves as a simple spin lock that we can use even
+// without an m. The thread that locks the stack in this way
+// unlocks the stack by storing a valid stack head pointer.
+//
+// In order to make sure that there is always an m structure
+// available to be stolen, we maintain the invariant that there
+// is always one more than needed. At the beginning of the
+// program (if cgo is in use) the list is seeded with a single m.
+// If needm finds that it has taken the last m off the list, its job
+// is - once it has installed its own m so that it can do things like
+// allocate memory - to create a spare m and put it on the list.
+//
+// Each of these extra m's also has a g0 and a curg that are
+// pressed into service as the scheduling stack and current
+// goroutine for the duration of the cgo callback.
+//
+// When the callback is done with the m, it calls dropm to
+// put the m back on the list.
+//
+//go:nosplit
+func needm() {
+	if (iscgo || GOOS == "windows") && !cgoHasExtraM {
+		// Can happen if C/C++ code calls Go from a global ctor.
+		// Can also happen on Windows if a global ctor uses a
+		// callback created by syscall.NewCallback. See issue #6751
+		// for details.
+		//
+		// Can not throw, because scheduler is not initialized yet.
+		write(2, unsafe.Pointer(&earlycgocallback[0]), int32(len(earlycgocallback)))
+		exit(1)
+	}
+
+	// Save and block signals before getting an M.
+	// The signal handler may call needm itself,
+	// and we must avoid a deadlock. Also, once g is installed,
+	// any incoming signals will try to execute,
+	// but we won't have the sigaltstack settings and other data
+	// set up appropriately until the end of minit, which will
+	// unblock the signals. This is the same dance as when
+	// starting a new m to run Go code via newosproc.
+	var sigmask sigset
+	sigsave(&sigmask)
+	sigblock(false)
+
+	// Lock extra list, take head, unlock popped list.
+	// nilokay=false is safe here because of the invariant above,
+	// that the extra list always contains or will soon contain
+	// at least one m.
+	mp := lockextra(false)
+
+	// Set needextram when we've just emptied the list,
+	// so that the eventual call into cgocallbackg will
+	// allocate a new m for the extra list. We delay the
+	// allocation until then so that it can be done
+	// after exitsyscall makes sure it is okay to be
+	// running at all (that is, there's no garbage collection
+	// running right now).
+	mp.needextram = mp.schedlink == 0
+	extraMCount--
+	unlockextra(mp.schedlink.ptr())
+
+	// Store the original signal mask for use by minit.
+	mp.sigmask = sigmask
+
+	// Install TLS on some platforms (previously setg
+	// would do this if necessary).
+	osSetupTLS(mp)
+
+	// Install g (= m->g0) and set the stack bounds
+	// to match the current stack. We don't actually know
+	// how big the stack is, like we don't know how big any
+	// scheduling stack is, but we assume there's at least 32 kB,
+	// which is more than enough for us.
+	setg(mp.g0)
+	_g_ := getg()
+	_g_.stack.hi = getcallersp() + 1024
+	_g_.stack.lo = getcallersp() - 32*1024
+	_g_.stackguard0 = _g_.stack.lo + _StackGuard
+
+	// Initialize this thread to use the m.
+	asminit()
+	minit()
+
+	// mp.curg is now a real goroutine.
+	casgstatus(mp.curg, _Gdead, _Gsyscall)
+	atomic.Xadd(&sched.ngsys, -1)
+}
+
+var earlycgocallback = []byte("fatal error: cgo callback before cgo call\n")
+
+// newextram allocates m's and puts them on the extra list.
+// It is called with a working local m, so that it can do things
+// like call schedlock and allocate.
+func newextram() {
+	c := atomic.Xchg(&extraMWaiters, 0)
+	if c > 0 {
+		for i := uint32(0); i < c; i++ {
+			oneNewExtraM()
+		}
+	} else {
+		// Make sure there is at least one extra M.
+		mp := lockextra(true)
+		unlockextra(mp)
+		if mp == nil {
+			oneNewExtraM()
+		}
+	}
+}
+
+// oneNewExtraM allocates an m and puts it on the extra list.
+func oneNewExtraM() {
+	// Create extra goroutine locked to extra m.
+	// The goroutine is the context in which the cgo callback will run.
+	// The sched.pc will never be returned to, but setting it to
+	// goexit makes clear to the traceback routines where
+	// the goroutine stack ends.
+	mp := allocm(nil, nil, -1)
+	gp := malg(4096)
+	gp.sched.pc = abi.FuncPCABI0(goexit) + sys.PCQuantum
+	gp.sched.sp = gp.stack.hi
+	gp.sched.sp -= 4 * goarch.PtrSize // extra space in case of reads slightly beyond frame
+	gp.sched.lr = 0
+	gp.sched.g = guintptr(unsafe.Pointer(gp))
+	gp.syscallpc = gp.sched.pc
+	gp.syscallsp = gp.sched.sp
+	gp.stktopsp = gp.sched.sp
+	// malg returns status as _Gidle. Change to _Gdead before
+	// adding to allg where GC can see it. We use _Gdead to hide
+	// this from tracebacks and stack scans since it isn't a
+	// "real" goroutine until needm grabs it.
+	casgstatus(gp, _Gidle, _Gdead)
+	gp.m = mp
+	mp.curg = gp
+	mp.lockedInt++
+	mp.lockedg.set(gp)
+	gp.lockedm.set(mp)
+	gp.goid = int64(atomic.Xadd64(&sched.goidgen, 1))
+	if raceenabled {
+		gp.racectx = racegostart(abi.FuncPCABIInternal(newextram) + sys.PCQuantum)
+	}
+	// put on allg for garbage collector
+	allgadd(gp)
+
+	// gp is now on the allg list, but we don't want it to be
+	// counted by gcount. It would be more "proper" to increment
+	// sched.ngfree, but that requires locking. Incrementing ngsys
+	// has the same effect.
+	atomic.Xadd(&sched.ngsys, +1)
+
+	// Add m to the extra list.
+	mnext := lockextra(true)
+	mp.schedlink.set(mnext)
+	extraMCount++
+	unlockextra(mp)
+}
+
+// dropm is called when a cgo callback has called needm but is now
+// done with the callback and returning back into the non-Go thread.
+// It puts the current m back onto the extra list.
+//
+// The main expense here is the call to signalstack to release the
+// m's signal stack, and then the call to needm on the next callback
+// from this thread. It is tempting to try to save the m for next time,
+// which would eliminate both these costs, but there might not be
+// a next time: the current thread (which Go does not control) might exit.
+// If we saved the m for that thread, there would be an m leak each time
+// such a thread exited. Instead, we acquire and release an m on each
+// call. These should typically not be scheduling operations, just a few
+// atomics, so the cost should be small.
+//
+// TODO(rsc): An alternative would be to allocate a dummy pthread per-thread
+// variable using pthread_key_create. Unlike the pthread keys we already use
+// on OS X, this dummy key would never be read by Go code. It would exist
+// only so that we could register at thread-exit-time destructor.
+// That destructor would put the m back onto the extra list.
+// This is purely a performance optimization. The current version,
+// in which dropm happens on each cgo call, is still correct too.
+// We may have to keep the current version on systems with cgo
+// but without pthreads, like Windows.
+func dropm() {
+	// Clear m and g, and return m to the extra list.
+	// After the call to setg we can only call nosplit functions
+	// with no pointer manipulation.
+	mp := getg().m
+
+	// Return mp.curg to dead state.
+	casgstatus(mp.curg, _Gsyscall, _Gdead)
+	mp.curg.preemptStop = false
+	atomic.Xadd(&sched.ngsys, +1)
+
+	// Block signals before unminit.
+	// Unminit unregisters the signal handling stack (but needs g on some systems).
+	// Setg(nil) clears g, which is the signal handler's cue not to run Go handlers.
+	// It's important not to try to handle a signal between those two steps.
+	sigmask := mp.sigmask
+	sigblock(false)
+	unminit()
+
+	mnext := lockextra(true)
+	extraMCount++
+	mp.schedlink.set(mnext)
+
+	setg(nil)
+
+	// Commit the release of mp.
+	unlockextra(mp)
+
+	msigrestore(sigmask)
+}
+
+// A helper function for EnsureDropM.
+func getm() uintptr {
+	return uintptr(unsafe.Pointer(getg().m))
+}
+
+var extram uintptr
+var extraMCount uint32 // Protected by lockextra
+var extraMWaiters uint32
+
+// lockextra locks the extra list and returns the list head.
+// The caller must unlock the list by storing a new list head
+// to extram. If nilokay is true, then lockextra will
+// return a nil list head if that's what it finds. If nilokay is false,
+// lockextra will keep waiting until the list head is no longer nil.
+//
+//go:nosplit
+func lockextra(nilokay bool) *m {
+	const locked = 1
+
+	incr := false
+	for {
+		old := atomic.Loaduintptr(&extram)
+		if old == locked {
+			osyield_no_g()
+			continue
+		}
+		if old == 0 && !nilokay {
+			if !incr {
+				// Add 1 to the number of threads
+				// waiting for an M.
+				// This is cleared by newextram.
+				atomic.Xadd(&extraMWaiters, 1)
+				incr = true
+			}
+			usleep_no_g(1)
+			continue
+		}
+		if atomic.Casuintptr(&extram, old, locked) {
+			return (*m)(unsafe.Pointer(old))
+		}
+		osyield_no_g()
+		continue
+	}
+}
+
+//go:nosplit
+func unlockextra(mp *m) {
+	atomic.Storeuintptr(&extram, uintptr(unsafe.Pointer(mp)))
+}
+
+var (
+	// allocmLock is locked for read when creating new Ms in allocm and their
+	// addition to allm. Thus acquiring this lock for write blocks the
+	// creation of new Ms.
+	allocmLock rwmutex
+
+	// execLock serializes exec and clone to avoid bugs or unspecified
+	// behaviour around exec'ing while creating/destroying threads. See
+	// issue #19546.
+	execLock rwmutex
+)
+
+// newmHandoff contains a list of m structures that need new OS threads.
+// This is used by newm in situations where newm itself can't safely
+// start an OS thread.
+var newmHandoff struct {
+	lock mutex
+
+	// newm points to a list of M structures that need new OS
+	// threads. The list is linked through m.schedlink.
+	newm muintptr
+
+	// waiting indicates that wake needs to be notified when an m
+	// is put on the list.
+	waiting bool
+	wake    note
+
+	// haveTemplateThread indicates that the templateThread has
+	// been started. This is not protected by lock. Use cas to set
+	// to 1.
+	haveTemplateThread uint32
+}
+
+// Create a new m. It will start off with a call to fn, or else the scheduler.
+// fn needs to be static and not a heap allocated closure.
+// May run with m.p==nil, so write barriers are not allowed.
+//
+// id is optional pre-allocated m ID. Omit by passing -1.
+//
+//go:nowritebarrierrec
+func newm(fn func(), _p_ *p, id int64) {
+	// allocm adds a new M to allm, but they do not start until created by
+	// the OS in newm1 or the template thread.
+	//
+	// doAllThreadsSyscall requires that every M in allm will eventually
+	// start and be signal-able, even with a STW.
+	//
+	// Disable preemption here until we start the thread to ensure that
+	// newm is not preempted between allocm and starting the new thread,
+	// ensuring that anything added to allm is guaranteed to eventually
+	// start.
+	acquirem()
+
+	mp := allocm(_p_, fn, id)
+	mp.nextp.set(_p_)
+	mp.sigmask = initSigmask
+	if gp := getg(); gp != nil && gp.m != nil && (gp.m.lockedExt != 0 || gp.m.incgo) && GOOS != "plan9" {
+		// We're on a locked M or a thread that may have been
+		// started by C. The kernel state of this thread may
+		// be strange (the user may have locked it for that
+		// purpose). We don't want to clone that into another
+		// thread. Instead, ask a known-good thread to create
+		// the thread for us.
+		//
+		// This is disabled on Plan 9. See golang.org/issue/22227.
+		//
+		// TODO: This may be unnecessary on Windows, which
+		// doesn't model thread creation off fork.
+		lock(&newmHandoff.lock)
+		if newmHandoff.haveTemplateThread == 0 {
+			throw("on a locked thread with no template thread")
+		}
+		mp.schedlink = newmHandoff.newm
+		newmHandoff.newm.set(mp)
+		if newmHandoff.waiting {
+			newmHandoff.waiting = false
+			notewakeup(&newmHandoff.wake)
+		}
+		unlock(&newmHandoff.lock)
+		// The M has not started yet, but the template thread does not
+		// participate in STW, so it will always process queued Ms and
+		// it is safe to releasem.
+		releasem(getg().m)
+		return
+	}
+	newm1(mp)
+	releasem(getg().m)
+}
+
+func newm1(mp *m) {
+	if iscgo {
+		var ts cgothreadstart
+		if _cgo_thread_start == nil {
+			throw("_cgo_thread_start missing")
+		}
+		ts.g.set(mp.g0)
+		ts.tls = (*uint64)(unsafe.Pointer(&mp.tls[0]))
+		ts.fn = unsafe.Pointer(abi.FuncPCABI0(mstart))
+		if msanenabled {
+			msanwrite(unsafe.Pointer(&ts), unsafe.Sizeof(ts))
+		}
+		if asanenabled {
+			asanwrite(unsafe.Pointer(&ts), unsafe.Sizeof(ts))
+		}
+		execLock.rlock() // Prevent process clone.
+		asmcgocall(_cgo_thread_start, unsafe.Pointer(&ts))
+		execLock.runlock()
+		return
+	}
+	execLock.rlock() // Prevent process clone.
+	newosproc(mp)
+	execLock.runlock()
+}
+
+// startTemplateThread starts the template thread if it is not already
+// running.
+//
+// The calling thread must itself be in a known-good state.
+func startTemplateThread() {
+	if GOARCH == "wasm" { // no threads on wasm yet
+		return
+	}
+
+	// Disable preemption to guarantee that the template thread will be
+	// created before a park once haveTemplateThread is set.
+	mp := acquirem()
+	if !atomic.Cas(&newmHandoff.haveTemplateThread, 0, 1) {
+		releasem(mp)
+		return
+	}
+	newm(templateThread, nil, -1)
+	releasem(mp)
+}
+
+// templateThread is a thread in a known-good state that exists solely
+// to start new threads in known-good states when the calling thread
+// may not be in a good state.
+//
+// Many programs never need this, so templateThread is started lazily
+// when we first enter a state that might lead to running on a thread
+// in an unknown state.
+//
+// templateThread runs on an M without a P, so it must not have write
+// barriers.
+//
+//go:nowritebarrierrec
+func templateThread() {
+	lock(&sched.lock)
+	sched.nmsys++
+	checkdead()
+	unlock(&sched.lock)
+
+	for {
+		lock(&newmHandoff.lock)
+		for newmHandoff.newm != 0 {
+			newm := newmHandoff.newm.ptr()
+			newmHandoff.newm = 0
+			unlock(&newmHandoff.lock)
+			for newm != nil {
+				next := newm.schedlink.ptr()
+				newm.schedlink = 0
+				newm1(newm)
+				newm = next
+			}
+			lock(&newmHandoff.lock)
+		}
+		newmHandoff.waiting = true
+		noteclear(&newmHandoff.wake)
+		unlock(&newmHandoff.lock)
+		notesleep(&newmHandoff.wake)
+	}
+}
+
+// Stops execution of the current m until new work is available.
+// Returns with acquired P.
+func stopm() {
+	_g_ := getg()
+
+	if _g_.m.locks != 0 {
+		throw("stopm holding locks")
+	}
+	if _g_.m.p != 0 {
+		throw("stopm holding p")
+	}
+	if _g_.m.spinning {
+		throw("stopm spinning")
+	}
+
+	lock(&sched.lock)
+	mput(_g_.m)
+	unlock(&sched.lock)
+	mPark()
+	acquirep(_g_.m.nextp.ptr())
+	_g_.m.nextp = 0
+}
+
+func mspinning() {
+	// startm's caller incremented nmspinning. Set the new M's spinning.
+	getg().m.spinning = true
+}
+
+// Schedules some M to run the p (creates an M if necessary).
+// If p==nil, tries to get an idle P, if no idle P's does nothing.
+// May run with m.p==nil, so write barriers are not allowed.
+// If spinning is set, the caller has incremented nmspinning and startm will
+// either decrement nmspinning or set m.spinning in the newly started M.
+//
+// Callers passing a non-nil P must call from a non-preemptible context. See
+// comment on acquirem below.
+//
+// Must not have write barriers because this may be called without a P.
+//
+//go:nowritebarrierrec
+func startm(_p_ *p, spinning bool) {
+	// Disable preemption.
+	//
+	// Every owned P must have an owner that will eventually stop it in the
+	// event of a GC stop request. startm takes transient ownership of a P
+	// (either from argument or pidleget below) and transfers ownership to
+	// a started M, which will be responsible for performing the stop.
+	//
+	// Preemption must be disabled during this transient ownership,
+	// otherwise the P this is running on may enter GC stop while still
+	// holding the transient P, leaving that P in limbo and deadlocking the
+	// STW.
+	//
+	// Callers passing a non-nil P must already be in non-preemptible
+	// context, otherwise such preemption could occur on function entry to
+	// startm. Callers passing a nil P may be preemptible, so we must
+	// disable preemption before acquiring a P from pidleget below.
+	mp := acquirem()
+	lock(&sched.lock)
+	if _p_ == nil {
+		_p_, _ = pidleget(0)
+		if _p_ == nil {
+			unlock(&sched.lock)
+			if spinning {
+				// The caller incremented nmspinning, but there are no idle Ps,
+				// so it's okay to just undo the increment and give up.
+				if int32(atomic.Xadd(&sched.nmspinning, -1)) < 0 {
+					throw("startm: negative nmspinning")
+				}
+			}
+			releasem(mp)
+			return
+		}
+	}
+	nmp := mget()
+	if nmp == nil {
+		// No M is available, we must drop sched.lock and call newm.
+		// However, we already own a P to assign to the M.
+		//
+		// Once sched.lock is released, another G (e.g., in a syscall),
+		// could find no idle P while checkdead finds a runnable G but
+		// no running M's because this new M hasn't started yet, thus
+		// throwing in an apparent deadlock.
+		//
+		// Avoid this situation by pre-allocating the ID for the new M,
+		// thus marking it as 'running' before we drop sched.lock. This
+		// new M will eventually run the scheduler to execute any
+		// queued G's.
+		id := mReserveID()
+		unlock(&sched.lock)
+
+		var fn func()
+		if spinning {
+			// The caller incremented nmspinning, so set m.spinning in the new M.
+			fn = mspinning
+		}
+		newm(fn, _p_, id)
+		// Ownership transfer of _p_ committed by start in newm.
+		// Preemption is now safe.
+		releasem(mp)
+		return
+	}
+	unlock(&sched.lock)
+	if nmp.spinning {
+		throw("startm: m is spinning")
+	}
+	if nmp.nextp != 0 {
+		throw("startm: m has p")
+	}
+	if spinning && !runqempty(_p_) {
+		throw("startm: p has runnable gs")
+	}
+	// The caller incremented nmspinning, so set m.spinning in the new M.
+	nmp.spinning = spinning
+	nmp.nextp.set(_p_)
+	notewakeup(&nmp.park)
+	// Ownership transfer of _p_ committed by wakeup. Preemption is now
+	// safe.
+	releasem(mp)
+}
+
+// Hands off P from syscall or locked M.
+// Always runs without a P, so write barriers are not allowed.
+//
+//go:nowritebarrierrec
+func handoffp(_p_ *p) {
+	// handoffp must start an M in any situation where
+	// findrunnable would return a G to run on _p_.
+
+	// if it has local work, start it straight away
+	if !runqempty(_p_) || sched.runqsize != 0 {
+		startm(_p_, false)
+		return
+	}
+	// if there's trace work to do, start it straight away
+	if (trace.enabled || trace.shutdown) && traceReaderAvailable() {
+		startm(_p_, false)
+		return
+	}
+	// if it has GC work, start it straight away
+	if gcBlackenEnabled != 0 && gcMarkWorkAvailable(_p_) {
+		startm(_p_, false)
+		return
+	}
+	// no local work, check that there are no spinning/idle M's,
+	// otherwise our help is not required
+	if atomic.Load(&sched.nmspinning)+atomic.Load(&sched.npidle) == 0 && atomic.Cas(&sched.nmspinning, 0, 1) { // TODO: fast atomic
+		startm(_p_, true)
+		return
+	}
+	lock(&sched.lock)
+	if sched.gcwaiting != 0 {
+		_p_.status = _Pgcstop
+		sched.stopwait--
+		if sched.stopwait == 0 {
+			notewakeup(&sched.stopnote)
+		}
+		unlock(&sched.lock)
+		return
+	}
+	if _p_.runSafePointFn != 0 && atomic.Cas(&_p_.runSafePointFn, 1, 0) {
+		sched.safePointFn(_p_)
+		sched.safePointWait--
+		if sched.safePointWait == 0 {
+			notewakeup(&sched.safePointNote)
+		}
+	}
+	if sched.runqsize != 0 {
+		unlock(&sched.lock)
+		startm(_p_, false)
+		return
+	}
+	// If this is the last running P and nobody is polling network,
+	// need to wakeup another M to poll network.
+	if sched.npidle == uint32(gomaxprocs-1) && atomic.Load64(&sched.lastpoll) != 0 {
+		unlock(&sched.lock)
+		startm(_p_, false)
+		return
+	}
+
+	// The scheduler lock cannot be held when calling wakeNetPoller below
+	// because wakeNetPoller may call wakep which may call startm.
+	when := nobarrierWakeTime(_p_)
+	pidleput(_p_, 0)
+	unlock(&sched.lock)
+
+	if when != 0 {
+		wakeNetPoller(when)
+	}
+}
+
+// Tries to add one more P to execute G's.
+// Called when a G is made runnable (newproc, ready).
+func wakep() {
+	if atomic.Load(&sched.npidle) == 0 {
+		return
+	}
+	// be conservative about spinning threads
+	if atomic.Load(&sched.nmspinning) != 0 || !atomic.Cas(&sched.nmspinning, 0, 1) {
+		return
+	}
+	startm(nil, true)
+}
+
+// Stops execution of the current m that is locked to a g until the g is runnable again.
+// Returns with acquired P.
+func stoplockedm() {
+	_g_ := getg()
+
+	if _g_.m.lockedg == 0 || _g_.m.lockedg.ptr().lockedm.ptr() != _g_.m {
+		throw("stoplockedm: inconsistent locking")
+	}
+	if _g_.m.p != 0 {
+		// Schedule another M to run this p.
+		_p_ := releasep()
+		handoffp(_p_)
+	}
+	incidlelocked(1)
+	// Wait until another thread schedules lockedg again.
+	mPark()
+	status := readgstatus(_g_.m.lockedg.ptr())
+	if status&^_Gscan != _Grunnable {
+		print("runtime:stoplockedm: lockedg (atomicstatus=", status, ") is not Grunnable or Gscanrunnable\n")
+		dumpgstatus(_g_.m.lockedg.ptr())
+		throw("stoplockedm: not runnable")
+	}
+	acquirep(_g_.m.nextp.ptr())
+	_g_.m.nextp = 0
+}
+
+// Schedules the locked m to run the locked gp.
+// May run during STW, so write barriers are not allowed.
+//
+//go:nowritebarrierrec
+func startlockedm(gp *g) {
+	_g_ := getg()
+
+	mp := gp.lockedm.ptr()
+	if mp == _g_.m {
+		throw("startlockedm: locked to me")
+	}
+	if mp.nextp != 0 {
+		throw("startlockedm: m has p")
+	}
+	// directly handoff current P to the locked m
+	incidlelocked(-1)
+	_p_ := releasep()
+	mp.nextp.set(_p_)
+	notewakeup(&mp.park)
+	stopm()
+}
+
+// Stops the current m for stopTheWorld.
+// Returns when the world is restarted.
+func gcstopm() {
+	_g_ := getg()
+
+	if sched.gcwaiting == 0 {
+		throw("gcstopm: not waiting for gc")
+	}
+	if _g_.m.spinning {
+		_g_.m.spinning = false
+		// OK to just drop nmspinning here,
+		// startTheWorld will unpark threads as necessary.
+		if int32(atomic.Xadd(&sched.nmspinning, -1)) < 0 {
+			throw("gcstopm: negative nmspinning")
+		}
+	}
+	_p_ := releasep()
+	lock(&sched.lock)
+	_p_.status = _Pgcstop
+	sched.stopwait--
+	if sched.stopwait == 0 {
+		notewakeup(&sched.stopnote)
+	}
+	unlock(&sched.lock)
+	stopm()
+}
+
+// Schedules gp to run on the current M.
+// If inheritTime is true, gp inherits the remaining time in the
+// current time slice. Otherwise, it starts a new time slice.
+// Never returns.
+//
+// Write barriers are allowed because this is called immediately after
+// acquiring a P in several places.
+//
+//go:yeswritebarrierrec
+func execute(gp *g, inheritTime bool) {
+	_g_ := getg()
+
+	if goroutineProfile.active {
+		// Make sure that gp has had its stack written out to the goroutine
+		// profile, exactly as it was when the goroutine profiler first stopped
+		// the world.
+		tryRecordGoroutineProfile(gp, osyield)
+	}
+
+	// Assign gp.m before entering _Grunning so running Gs have an
+	// M.
+	_g_.m.curg = gp
+	gp.m = _g_.m
+	casgstatus(gp, _Grunnable, _Grunning)
+	gp.waitsince = 0
+	gp.preempt = false
+	gp.stackguard0 = gp.stack.lo + _StackGuard
+	if !inheritTime {
+		_g_.m.p.ptr().schedtick++
+	}
+
+	// Check whether the profiler needs to be turned on or off.
+	hz := sched.profilehz
+	if _g_.m.profilehz != hz {
+		setThreadCPUProfiler(hz)
+	}
+
+	if trace.enabled {
+		// GoSysExit has to happen when we have a P, but before GoStart.
+		// So we emit it here.
+		if gp.syscallsp != 0 && gp.sysblocktraced {
+			traceGoSysExit(gp.sysexitticks)
+		}
+		traceGoStart()
+	}
+
+	gogo(&gp.sched)
+}
+
+// Finds a runnable goroutine to execute.
+// Tries to steal from other P's, get g from local or global queue, poll network.
+// tryWakeP indicates that the returned goroutine is not normal (GC worker, trace
+// reader) so the caller should try to wake a P.
+func findRunnable() (gp *g, inheritTime, tryWakeP bool) {
+	_g_ := getg()
+
+	// The conditions here and in handoffp must agree: if
+	// findrunnable would return a G to run, handoffp must start
+	// an M.
+
+top:
+	_p_ := _g_.m.p.ptr()
+	if sched.gcwaiting != 0 {
+		gcstopm()
+		goto top
+	}
+	if _p_.runSafePointFn != 0 {
+		runSafePointFn()
+	}
+
+	// now and pollUntil are saved for work stealing later,
+	// which may steal timers. It's important that between now
+	// and then, nothing blocks, so these numbers remain mostly
+	// relevant.
+	now, pollUntil, _ := checkTimers(_p_, 0)
+
+	// Try to schedule the trace reader.
+	if trace.enabled || trace.shutdown {
+		gp = traceReader()
+		if gp != nil {
+			casgstatus(gp, _Gwaiting, _Grunnable)
+			traceGoUnpark(gp, 0)
+			return gp, false, true
+		}
+	}
+
+	// Try to schedule a GC worker.
+	if gcBlackenEnabled != 0 {
+		gp, now = gcController.findRunnableGCWorker(_p_, now)
+		if gp != nil {
+			return gp, false, true
+		}
+	}
+
+	// Check the global runnable queue once in a while to ensure fairness.
+	// Otherwise two goroutines can completely occupy the local runqueue
+	// by constantly respawning each other.
+	if _p_.schedtick%61 == 0 && sched.runqsize > 0 {
+		lock(&sched.lock)
+		gp = globrunqget(_p_, 1)
+		unlock(&sched.lock)
+		if gp != nil {
+			return gp, false, false
+		}
+	}
+
+	// Wake up the finalizer G.
+	if fingwait && fingwake {
+		if gp := wakefing(); gp != nil {
+			ready(gp, 0, true)
+		}
+	}
+	if *cgo_yield != nil {
+		asmcgocall(*cgo_yield, nil)
+	}
+
+	// local runq
+	if gp, inheritTime := runqget(_p_); gp != nil {
+		return gp, inheritTime, false
+	}
+
+	// global runq
+	if sched.runqsize != 0 {
+		lock(&sched.lock)
+		gp := globrunqget(_p_, 0)
+		unlock(&sched.lock)
+		if gp != nil {
+			return gp, false, false
+		}
+	}
+
+	// Poll network.
+	// This netpoll is only an optimization before we resort to stealing.
+	// We can safely skip it if there are no waiters or a thread is blocked
+	// in netpoll already. If there is any kind of logical race with that
+	// blocked thread (e.g. it has already returned from netpoll, but does
+	// not set lastpoll yet), this thread will do blocking netpoll below
+	// anyway.
+	if netpollinited() && atomic.Load(&netpollWaiters) > 0 && atomic.Load64(&sched.lastpoll) != 0 {
+		if list := netpoll(0); !list.empty() { // non-blocking
+			gp := list.pop()
+			injectglist(&list)
+			casgstatus(gp, _Gwaiting, _Grunnable)
+			if trace.enabled {
+				traceGoUnpark(gp, 0)
+			}
+			return gp, false, false
+		}
+	}
+
+	// Spinning Ms: steal work from other Ps.
+	//
+	// Limit the number of spinning Ms to half the number of busy Ps.
+	// This is necessary to prevent excessive CPU consumption when
+	// GOMAXPROCS>>1 but the program parallelism is low.
+	procs := uint32(gomaxprocs)
+	if _g_.m.spinning || 2*atomic.Load(&sched.nmspinning) < procs-atomic.Load(&sched.npidle) {
+		if !_g_.m.spinning {
+			_g_.m.spinning = true
+			atomic.Xadd(&sched.nmspinning, 1)
+		}
+
+		gp, inheritTime, tnow, w, newWork := stealWork(now)
+		now = tnow
+		if gp != nil {
+			// Successfully stole.
+			return gp, inheritTime, false
+		}
+		if newWork {
+			// There may be new timer or GC work; restart to
+			// discover.
+			goto top
+		}
+		if w != 0 && (pollUntil == 0 || w < pollUntil) {
+			// Earlier timer to wait for.
+			pollUntil = w
+		}
+	}
+
+	// We have nothing to do.
+	//
+	// If we're in the GC mark phase, can safely scan and blacken objects,
+	// and have work to do, run idle-time marking rather than give up the P.
+	if gcBlackenEnabled != 0 && gcMarkWorkAvailable(_p_) && gcController.addIdleMarkWorker() {
+		node := (*gcBgMarkWorkerNode)(gcBgMarkWorkerPool.pop())
+		if node != nil {
+			_p_.gcMarkWorkerMode = gcMarkWorkerIdleMode
+			gp := node.gp.ptr()
+			casgstatus(gp, _Gwaiting, _Grunnable)
+			if trace.enabled {
+				traceGoUnpark(gp, 0)
+			}
+			return gp, false, false
+		}
+		gcController.removeIdleMarkWorker()
+	}
+
+	// wasm only:
+	// If a callback returned and no other goroutine is awake,
+	// then wake event handler goroutine which pauses execution
+	// until a callback was triggered.
+	gp, otherReady := beforeIdle(now, pollUntil)
+	if gp != nil {
+		casgstatus(gp, _Gwaiting, _Grunnable)
+		if trace.enabled {
+			traceGoUnpark(gp, 0)
+		}
+		return gp, false, false
+	}
+	if otherReady {
+		goto top
+	}
+
+	// Before we drop our P, make a snapshot of the allp slice,
+	// which can change underfoot once we no longer block
+	// safe-points. We don't need to snapshot the contents because
+	// everything up to cap(allp) is immutable.
+	allpSnapshot := allp
+	// Also snapshot masks. Value changes are OK, but we can't allow
+	// len to change out from under us.
+	idlepMaskSnapshot := idlepMask
+	timerpMaskSnapshot := timerpMask
+
+	// return P and block
+	lock(&sched.lock)
+	if sched.gcwaiting != 0 || _p_.runSafePointFn != 0 {
+		unlock(&sched.lock)
+		goto top
+	}
+	if sched.runqsize != 0 {
+		gp := globrunqget(_p_, 0)
+		unlock(&sched.lock)
+		return gp, false, false
+	}
+	if releasep() != _p_ {
+		throw("findrunnable: wrong p")
+	}
+	now = pidleput(_p_, now)
+	unlock(&sched.lock)
+
+	// Delicate dance: thread transitions from spinning to non-spinning
+	// state, potentially concurrently with submission of new work. We must
+	// drop nmspinning first and then check all sources again (with
+	// #StoreLoad memory barrier in between). If we do it the other way
+	// around, another thread can submit work after we've checked all
+	// sources but before we drop nmspinning; as a result nobody will
+	// unpark a thread to run the work.
+	//
+	// This applies to the following sources of work:
+	//
+	// * Goroutines added to a per-P run queue.
+	// * New/modified-earlier timers on a per-P timer heap.
+	// * Idle-priority GC work (barring golang.org/issue/19112).
+	//
+	// If we discover new work below, we need to restore m.spinning as a signal
+	// for resetspinning to unpark a new worker thread (because there can be more
+	// than one starving goroutine). However, if after discovering new work
+	// we also observe no idle Ps it is OK to skip unparking a new worker
+	// thread: the system is fully loaded so no spinning threads are required.
+	// Also see "Worker thread parking/unparking" comment at the top of the file.
+	wasSpinning := _g_.m.spinning
+	if _g_.m.spinning {
+		_g_.m.spinning = false
+		if int32(atomic.Xadd(&sched.nmspinning, -1)) < 0 {
+			throw("findrunnable: negative nmspinning")
+		}
+
+		// Note the for correctness, only the last M transitioning from
+		// spinning to non-spinning must perform these rechecks to
+		// ensure no missed work. We are performing it on every M that
+		// transitions as a conservative change to monitor effects on
+		// latency. See golang.org/issue/43997.
+
+		// Check all runqueues once again.
+		_p_ = checkRunqsNoP(allpSnapshot, idlepMaskSnapshot)
+		if _p_ != nil {
+			acquirep(_p_)
+			_g_.m.spinning = true
+			atomic.Xadd(&sched.nmspinning, 1)
+			goto top
+		}
+
+		// Check for idle-priority GC work again.
+		_p_, gp = checkIdleGCNoP()
+		if _p_ != nil {
+			acquirep(_p_)
+			_g_.m.spinning = true
+			atomic.Xadd(&sched.nmspinning, 1)
+
+			// Run the idle worker.
+			_p_.gcMarkWorkerMode = gcMarkWorkerIdleMode
+			casgstatus(gp, _Gwaiting, _Grunnable)
+			if trace.enabled {
+				traceGoUnpark(gp, 0)
+			}
+			return gp, false, false
+		}
+
+		// Finally, check for timer creation or expiry concurrently with
+		// transitioning from spinning to non-spinning.
+		//
+		// Note that we cannot use checkTimers here because it calls
+		// adjusttimers which may need to allocate memory, and that isn't
+		// allowed when we don't have an active P.
+		pollUntil = checkTimersNoP(allpSnapshot, timerpMaskSnapshot, pollUntil)
+	}
+
+	// Poll network until next timer.
+	if netpollinited() && (atomic.Load(&netpollWaiters) > 0 || pollUntil != 0) && atomic.Xchg64(&sched.lastpoll, 0) != 0 {
+		atomic.Store64(&sched.pollUntil, uint64(pollUntil))
+		if _g_.m.p != 0 {
+			throw("findrunnable: netpoll with p")
+		}
+		if _g_.m.spinning {
+			throw("findrunnable: netpoll with spinning")
+		}
+		// Refresh now.
+		now = nanotime()
+		delay := int64(-1)
+		if pollUntil != 0 {
+			delay = pollUntil - now
+			if delay < 0 {
+				delay = 0
+			}
+		}
+		if faketime != 0 {
+			// When using fake time, just poll.
+			delay = 0
+		}
+		list := netpoll(delay) // block until new work is available
+		atomic.Store64(&sched.pollUntil, 0)
+		atomic.Store64(&sched.lastpoll, uint64(now))
+		if faketime != 0 && list.empty() {
+			// Using fake time and nothing is ready; stop M.
+			// When all M's stop, checkdead will call timejump.
+			stopm()
+			goto top
+		}
+		lock(&sched.lock)
+		_p_, _ = pidleget(now)
+		unlock(&sched.lock)
+		if _p_ == nil {
+			injectglist(&list)
+		} else {
+			acquirep(_p_)
+			if !list.empty() {
+				gp := list.pop()
+				injectglist(&list)
+				casgstatus(gp, _Gwaiting, _Grunnable)
+				if trace.enabled {
+					traceGoUnpark(gp, 0)
+				}
+				return gp, false, false
+			}
+			if wasSpinning {
+				_g_.m.spinning = true
+				atomic.Xadd(&sched.nmspinning, 1)
+			}
+			goto top
+		}
+	} else if pollUntil != 0 && netpollinited() {
+		pollerPollUntil := int64(atomic.Load64(&sched.pollUntil))
+		if pollerPollUntil == 0 || pollerPollUntil > pollUntil {
+			netpollBreak()
+		}
+	}
+	stopm()
+	goto top
+}
+
+// pollWork reports whether there is non-background work this P could
+// be doing. This is a fairly lightweight check to be used for
+// background work loops, like idle GC. It checks a subset of the
+// conditions checked by the actual scheduler.
+func pollWork() bool {
+	if sched.runqsize != 0 {
+		return true
+	}
+	p := getg().m.p.ptr()
+	if !runqempty(p) {
+		return true
+	}
+	if netpollinited() && atomic.Load(&netpollWaiters) > 0 && sched.lastpoll != 0 {
+		if list := netpoll(0); !list.empty() {
+			injectglist(&list)
+			return true
+		}
+	}
+	return false
+}
+
+// stealWork attempts to steal a runnable goroutine or timer from any P.
+//
+// If newWork is true, new work may have been readied.
+//
+// If now is not 0 it is the current time. stealWork returns the passed time or
+// the current time if now was passed as 0.
+func stealWork(now int64) (gp *g, inheritTime bool, rnow, pollUntil int64, newWork bool) {
+	pp := getg().m.p.ptr()
+
+	ranTimer := false
+
+	const stealTries = 4
+	for i := 0; i < stealTries; i++ {
+		stealTimersOrRunNextG := i == stealTries-1
+
+		for enum := stealOrder.start(fastrand()); !enum.done(); enum.next() {
+			if sched.gcwaiting != 0 {
+				// GC work may be available.
+				return nil, false, now, pollUntil, true
+			}
+			p2 := allp[enum.position()]
+			if pp == p2 {
+				continue
+			}
+
+			// Steal timers from p2. This call to checkTimers is the only place
+			// where we might hold a lock on a different P's timers. We do this
+			// once on the last pass before checking runnext because stealing
+			// from the other P's runnext should be the last resort, so if there
+			// are timers to steal do that first.
+			//
+			// We only check timers on one of the stealing iterations because
+			// the time stored in now doesn't change in this loop and checking
+			// the timers for each P more than once with the same value of now
+			// is probably a waste of time.
+			//
+			// timerpMask tells us whether the P may have timers at all. If it
+			// can't, no need to check at all.
+			if stealTimersOrRunNextG && timerpMask.read(enum.position()) {
+				tnow, w, ran := checkTimers(p2, now)
+				now = tnow
+				if w != 0 && (pollUntil == 0 || w < pollUntil) {
+					pollUntil = w
+				}
+				if ran {
+					// Running the timers may have
+					// made an arbitrary number of G's
+					// ready and added them to this P's
+					// local run queue. That invalidates
+					// the assumption of runqsteal
+					// that it always has room to add
+					// stolen G's. So check now if there
+					// is a local G to run.
+					if gp, inheritTime := runqget(pp); gp != nil {
+						return gp, inheritTime, now, pollUntil, ranTimer
+					}
+					ranTimer = true
+				}
+			}
+
+			// Don't bother to attempt to steal if p2 is idle.
+			if !idlepMask.read(enum.position()) {
+				if gp := runqsteal(pp, p2, stealTimersOrRunNextG); gp != nil {
+					return gp, false, now, pollUntil, ranTimer
+				}
+			}
+		}
+	}
+
+	// No goroutines found to steal. Regardless, running a timer may have
+	// made some goroutine ready that we missed. Indicate the next timer to
+	// wait for.
+	return nil, false, now, pollUntil, ranTimer
+}
+
+// Check all Ps for a runnable G to steal.
+//
+// On entry we have no P. If a G is available to steal and a P is available,
+// the P is returned which the caller should acquire and attempt to steal the
+// work to.
+func checkRunqsNoP(allpSnapshot []*p, idlepMaskSnapshot pMask) *p {
+	for id, p2 := range allpSnapshot {
+		if !idlepMaskSnapshot.read(uint32(id)) && !runqempty(p2) {
+			lock(&sched.lock)
+			pp, _ := pidleget(0)
+			unlock(&sched.lock)
+			if pp != nil {
+				return pp
+			}
+
+			// Can't get a P, don't bother checking remaining Ps.
+			break
+		}
+	}
+
+	return nil
+}
+
+// Check all Ps for a timer expiring sooner than pollUntil.
+//
+// Returns updated pollUntil value.
+func checkTimersNoP(allpSnapshot []*p, timerpMaskSnapshot pMask, pollUntil int64) int64 {
+	for id, p2 := range allpSnapshot {
+		if timerpMaskSnapshot.read(uint32(id)) {
+			w := nobarrierWakeTime(p2)
+			if w != 0 && (pollUntil == 0 || w < pollUntil) {
+				pollUntil = w
+			}
+		}
+	}
+
+	return pollUntil
+}
+
+// Check for idle-priority GC, without a P on entry.
+//
+// If some GC work, a P, and a worker G are all available, the P and G will be
+// returned. The returned P has not been wired yet.
+func checkIdleGCNoP() (*p, *g) {
+	// N.B. Since we have no P, gcBlackenEnabled may change at any time; we
+	// must check again after acquiring a P. As an optimization, we also check
+	// if an idle mark worker is needed at all. This is OK here, because if we
+	// observe that one isn't needed, at least one is currently running. Even if
+	// it stops running, its own journey into the scheduler should schedule it
+	// again, if need be (at which point, this check will pass, if relevant).
+	if atomic.Load(&gcBlackenEnabled) == 0 || !gcController.needIdleMarkWorker() {
+		return nil, nil
+	}
+	if !gcMarkWorkAvailable(nil) {
+		return nil, nil
+	}
+
+	// Work is available; we can start an idle GC worker only if there is
+	// an available P and available worker G.
+	//
+	// We can attempt to acquire these in either order, though both have
+	// synchronization concerns (see below). Workers are almost always
+	// available (see comment in findRunnableGCWorker for the one case
+	// there may be none). Since we're slightly less likely to find a P,
+	// check for that first.
+	//
+	// Synchronization: note that we must hold sched.lock until we are
+	// committed to keeping it. Otherwise we cannot put the unnecessary P
+	// back in sched.pidle without performing the full set of idle
+	// transition checks.
+	//
+	// If we were to check gcBgMarkWorkerPool first, we must somehow handle
+	// the assumption in gcControllerState.findRunnableGCWorker that an
+	// empty gcBgMarkWorkerPool is only possible if gcMarkDone is running.
+	lock(&sched.lock)
+	pp, now := pidleget(0)
+	if pp == nil {
+		unlock(&sched.lock)
+		return nil, nil
+	}
+
+	// Now that we own a P, gcBlackenEnabled can't change (as it requires STW).
+	if gcBlackenEnabled == 0 || !gcController.addIdleMarkWorker() {
+		pidleput(pp, now)
+		unlock(&sched.lock)
+		return nil, nil
+	}
+
+	node := (*gcBgMarkWorkerNode)(gcBgMarkWorkerPool.pop())
+	if node == nil {
+		pidleput(pp, now)
+		unlock(&sched.lock)
+		gcController.removeIdleMarkWorker()
+		return nil, nil
+	}
+
+	unlock(&sched.lock)
+
+	return pp, node.gp.ptr()
+}
+
+// wakeNetPoller wakes up the thread sleeping in the network poller if it isn't
+// going to wake up before the when argument; or it wakes an idle P to service
+// timers and the network poller if there isn't one already.
+func wakeNetPoller(when int64) {
+	if atomic.Load64(&sched.lastpoll) == 0 {
+		// In findrunnable we ensure that when polling the pollUntil
+		// field is either zero or the time to which the current
+		// poll is expected to run. This can have a spurious wakeup
+		// but should never miss a wakeup.
+		pollerPollUntil := int64(atomic.Load64(&sched.pollUntil))
+		if pollerPollUntil == 0 || pollerPollUntil > when {
+			netpollBreak()
+		}
+	} else {
+		// There are no threads in the network poller, try to get
+		// one there so it can handle new timers.
+		if GOOS != "plan9" { // Temporary workaround - see issue #42303.
+			wakep()
+		}
+	}
+}
+
+func resetspinning() {
+	_g_ := getg()
+	if !_g_.m.spinning {
+		throw("resetspinning: not a spinning m")
+	}
+	_g_.m.spinning = false
+	nmspinning := atomic.Xadd(&sched.nmspinning, -1)
+	if int32(nmspinning) < 0 {
+		throw("findrunnable: negative nmspinning")
+	}
+	// M wakeup policy is deliberately somewhat conservative, so check if we
+	// need to wakeup another P here. See "Worker thread parking/unparking"
+	// comment at the top of the file for details.
+	wakep()
+}
+
+// injectglist adds each runnable G on the list to some run queue,
+// and clears glist. If there is no current P, they are added to the
+// global queue, and up to npidle M's are started to run them.
+// Otherwise, for each idle P, this adds a G to the global queue
+// and starts an M. Any remaining G's are added to the current P's
+// local run queue.
+// This may temporarily acquire sched.lock.
+// Can run concurrently with GC.
+func injectglist(glist *gList) {
+	if glist.empty() {
+		return
+	}
+	if trace.enabled {
+		for gp := glist.head.ptr(); gp != nil; gp = gp.schedlink.ptr() {
+			traceGoUnpark(gp, 0)
+		}
+	}
+
+	// Mark all the goroutines as runnable before we put them
+	// on the run queues.
+	head := glist.head.ptr()
+	var tail *g
+	qsize := 0
+	for gp := head; gp != nil; gp = gp.schedlink.ptr() {
+		tail = gp
+		qsize++
+		casgstatus(gp, _Gwaiting, _Grunnable)
+	}
+
+	// Turn the gList into a gQueue.
+	var q gQueue
+	q.head.set(head)
+	q.tail.set(tail)
+	*glist = gList{}
+
+	startIdle := func(n int) {
+		for ; n != 0 && sched.npidle != 0; n-- {
+			startm(nil, false)
+		}
+	}
+
+	pp := getg().m.p.ptr()
+	if pp == nil {
+		lock(&sched.lock)
+		globrunqputbatch(&q, int32(qsize))
+		unlock(&sched.lock)
+		startIdle(qsize)
+		return
+	}
+
+	npidle := int(atomic.Load(&sched.npidle))
+	var globq gQueue
+	var n int
+	for n = 0; n < npidle && !q.empty(); n++ {
+		g := q.pop()
+		globq.pushBack(g)
+	}
+	if n > 0 {
+		lock(&sched.lock)
+		globrunqputbatch(&globq, int32(n))
+		unlock(&sched.lock)
+		startIdle(n)
+		qsize -= n
+	}
+
+	if !q.empty() {
+		runqputbatch(pp, &q, qsize)
+	}
+}
+
+// One round of scheduler: find a runnable goroutine and execute it.
+// Never returns.
+func schedule() {
+	_g_ := getg()
+
+	if _g_.m.locks != 0 {
+		throw("schedule: holding locks")
+	}
+
+	if _g_.m.lockedg != 0 {
+		stoplockedm()
+		execute(_g_.m.lockedg.ptr(), false) // Never returns.
+	}
+
+	// We should not schedule away from a g that is executing a cgo call,
+	// since the cgo call is using the m's g0 stack.
+	if _g_.m.incgo {
+		throw("schedule: in cgo")
+	}
+
+top:
+	pp := _g_.m.p.ptr()
+	pp.preempt = false
+
+	// Safety check: if we are spinning, the run queue should be empty.
+	// Check this before calling checkTimers, as that might call
+	// goready to put a ready goroutine on the local run queue.
+	if _g_.m.spinning && (pp.runnext != 0 || pp.runqhead != pp.runqtail) {
+		throw("schedule: spinning with local work")
+	}
+
+	gp, inheritTime, tryWakeP := findRunnable() // blocks until work is available
+
+	// This thread is going to run a goroutine and is not spinning anymore,
+	// so if it was marked as spinning we need to reset it now and potentially
+	// start a new spinning M.
+	if _g_.m.spinning {
+		resetspinning()
+	}
+
+	if sched.disable.user && !schedEnabled(gp) {
+		// Scheduling of this goroutine is disabled. Put it on
+		// the list of pending runnable goroutines for when we
+		// re-enable user scheduling and look again.
+		lock(&sched.lock)
+		if schedEnabled(gp) {
+			// Something re-enabled scheduling while we
+			// were acquiring the lock.
+			unlock(&sched.lock)
+		} else {
+			sched.disable.runnable.pushBack(gp)
+			sched.disable.n++
+			unlock(&sched.lock)
+			goto top
+		}
+	}
+
+	// If about to schedule a not-normal goroutine (a GCworker or tracereader),
+	// wake a P if there is one.
+	if tryWakeP {
+		wakep()
+	}
+	if gp.lockedm != 0 {
+		// Hands off own p to the locked m,
+		// then blocks waiting for a new p.
+		startlockedm(gp)
+		goto top
+	}
+
+	execute(gp, inheritTime)
+}
+
+// dropg removes the association between m and the current goroutine m->curg (gp for short).
+// Typically a caller sets gp's status away from Grunning and then
+// immediately calls dropg to finish the job. The caller is also responsible
+// for arranging that gp will be restarted using ready at an
+// appropriate time. After calling dropg and arranging for gp to be
+// readied later, the caller can do other work but eventually should
+// call schedule to restart the scheduling of goroutines on this m.
+func dropg() {
+	_g_ := getg()
+
+	setMNoWB(&_g_.m.curg.m, nil)
+	setGNoWB(&_g_.m.curg, nil)
+}
+
+// checkTimers runs any timers for the P that are ready.
+// If now is not 0 it is the current time.
+// It returns the passed time or the current time if now was passed as 0.
+// and the time when the next timer should run or 0 if there is no next timer,
+// and reports whether it ran any timers.
+// If the time when the next timer should run is not 0,
+// it is always larger than the returned time.
+// We pass now in and out to avoid extra calls of nanotime.
+//
+//go:yeswritebarrierrec
+func checkTimers(pp *p, now int64) (rnow, pollUntil int64, ran bool) {
+	// If it's not yet time for the first timer, or the first adjusted
+	// timer, then there is nothing to do.
+	next := int64(atomic.Load64(&pp.timer0When))
+	nextAdj := int64(atomic.Load64(&pp.timerModifiedEarliest))
+	if next == 0 || (nextAdj != 0 && nextAdj < next) {
+		next = nextAdj
+	}
+
+	if next == 0 {
+		// No timers to run or adjust.
+		return now, 0, false
+	}
+
+	if now == 0 {
+		now = nanotime()
+	}
+	if now < next {
+		// Next timer is not ready to run, but keep going
+		// if we would clear deleted timers.
+		// This corresponds to the condition below where
+		// we decide whether to call clearDeletedTimers.
+		if pp != getg().m.p.ptr() || int(atomic.Load(&pp.deletedTimers)) <= int(atomic.Load(&pp.numTimers)/4) {
+			return now, next, false
+		}
+	}
+
+	lock(&pp.timersLock)
+
+	if len(pp.timers) > 0 {
+		adjusttimers(pp, now)
+		for len(pp.timers) > 0 {
+			// Note that runtimer may temporarily unlock
+			// pp.timersLock.
+			if tw := runtimer(pp, now); tw != 0 {
+				if tw > 0 {
+					pollUntil = tw
+				}
+				break
+			}
+			ran = true
+		}
+	}
+
+	// If this is the local P, and there are a lot of deleted timers,
+	// clear them out. We only do this for the local P to reduce
+	// lock contention on timersLock.
+	if pp == getg().m.p.ptr() && int(atomic.Load(&pp.deletedTimers)) > len(pp.timers)/4 {
+		clearDeletedTimers(pp)
+	}
+
+	unlock(&pp.timersLock)
+
+	return now, pollUntil, ran
+}
+
+func parkunlock_c(gp *g, lock unsafe.Pointer) bool {
+	unlock((*mutex)(lock))
+	return true
+}
+
+// park continuation on g0.
+func park_m(gp *g) {
+	_g_ := getg()
+
+	if trace.enabled {
+		traceGoPark(_g_.m.waittraceev, _g_.m.waittraceskip)
+	}
+
+	casgstatus(gp, _Grunning, _Gwaiting)
+	dropg()
+
+	if fn := _g_.m.waitunlockf; fn != nil {
+		ok := fn(gp, _g_.m.waitlock)
+		_g_.m.waitunlockf = nil
+		_g_.m.waitlock = nil
+		if !ok {
+			if trace.enabled {
+				traceGoUnpark(gp, 2)
+			}
+			casgstatus(gp, _Gwaiting, _Grunnable)
+			execute(gp, true) // Schedule it back, never returns.
+		}
+	}
+	schedule()
+}
+
+func goschedImpl(gp *g) {
+	status := readgstatus(gp)
+	if status&^_Gscan != _Grunning {
+		dumpgstatus(gp)
+		throw("bad g status")
+	}
+	casgstatus(gp, _Grunning, _Grunnable)
+	dropg()
+	lock(&sched.lock)
+	globrunqput(gp)
+	unlock(&sched.lock)
+
+	schedule()
+}
+
+// Gosched continuation on g0.
+func gosched_m(gp *g) {
+	if trace.enabled {
+		traceGoSched()
+	}
+	goschedImpl(gp)
+}
+
+// goschedguarded is a forbidden-states-avoided version of gosched_m
+func goschedguarded_m(gp *g) {
+
+	if !canPreemptM(gp.m) {
+		gogo(&gp.sched) // never return
+	}
+
+	if trace.enabled {
+		traceGoSched()
+	}
+	goschedImpl(gp)
+}
+
+func gopreempt_m(gp *g) {
+	if trace.enabled {
+		traceGoPreempt()
+	}
+	goschedImpl(gp)
+}
+
+// preemptPark parks gp and puts it in _Gpreempted.
+//
+//go:systemstack
+func preemptPark(gp *g) {
+	if trace.enabled {
+		traceGoPark(traceEvGoBlock, 0)
+	}
+	status := readgstatus(gp)
+	if status&^_Gscan != _Grunning {
+		dumpgstatus(gp)
+		throw("bad g status")
+	}
+	gp.waitreason = waitReasonPreempted
+
+	if gp.asyncSafePoint {
+		// Double-check that async preemption does not
+		// happen in SPWRITE assembly functions.
+		// isAsyncSafePoint must exclude this case.
+		f := findfunc(gp.sched.pc)
+		if !f.valid() {
+			throw("preempt at unknown pc")
+		}
+		if f.flag&funcFlag_SPWRITE != 0 {
+			println("runtime: unexpected SPWRITE function", funcname(f), "in async preempt")
+			throw("preempt SPWRITE")
+		}
+	}
+
+	// Transition from _Grunning to _Gscan|_Gpreempted. We can't
+	// be in _Grunning when we dropg because then we'd be running
+	// without an M, but the moment we're in _Gpreempted,
+	// something could claim this G before we've fully cleaned it
+	// up. Hence, we set the scan bit to lock down further
+	// transitions until we can dropg.
+	casGToPreemptScan(gp, _Grunning, _Gscan|_Gpreempted)
+	dropg()
+	casfrom_Gscanstatus(gp, _Gscan|_Gpreempted, _Gpreempted)
+	schedule()
+}
+
+// goyield is like Gosched, but it:
+// - emits a GoPreempt trace event instead of a GoSched trace event
+// - puts the current G on the runq of the current P instead of the globrunq
+func goyield() {
+	checkTimeouts()
+	mcall(goyield_m)
+}
+
+func goyield_m(gp *g) {
+	if trace.enabled {
+		traceGoPreempt()
+	}
+	pp := gp.m.p.ptr()
+	casgstatus(gp, _Grunning, _Grunnable)
+	dropg()
+	runqput(pp, gp, false)
+	schedule()
+}
+
+// Finishes execution of the current goroutine.
+func goexit1() {
+	if raceenabled {
+		racegoend()
+	}
+	if trace.enabled {
+		traceGoEnd()
+	}
+	mcall(goexit0)
+}
+
+// goexit continuation on g0.
+func goexit0(gp *g) {
+	_g_ := getg()
+	_p_ := _g_.m.p.ptr()
+
+	casgstatus(gp, _Grunning, _Gdead)
+	gcController.addScannableStack(_p_, -int64(gp.stack.hi-gp.stack.lo))
+	if isSystemGoroutine(gp, false) {
+		atomic.Xadd(&sched.ngsys, -1)
+	}
+	gp.m = nil
+	locked := gp.lockedm != 0
+	gp.lockedm = 0
+	_g_.m.lockedg = 0
+	gp.preemptStop = false
+	gp.paniconfault = false
+	gp._defer = nil // should be true already but just in case.
+	gp._panic = nil // non-nil for Goexit during panic. points at stack-allocated data.
+	gp.writebuf = nil
+	gp.waitreason = 0
+	gp.param = nil
+	gp.labels = nil
+	gp.timer = nil
+
+	if gcBlackenEnabled != 0 && gp.gcAssistBytes > 0 {
+		// Flush assist credit to the global pool. This gives
+		// better information to pacing if the application is
+		// rapidly creating an exiting goroutines.
+		assistWorkPerByte := gcController.assistWorkPerByte.Load()
+		scanCredit := int64(assistWorkPerByte * float64(gp.gcAssistBytes))
+		atomic.Xaddint64(&gcController.bgScanCredit, scanCredit)
+		gp.gcAssistBytes = 0
+	}
+
+	dropg()
+
+	if GOARCH == "wasm" { // no threads yet on wasm
+		gfput(_p_, gp)
+		schedule() // never returns
+	}
+
+	if _g_.m.lockedInt != 0 {
+		print("invalid m->lockedInt = ", _g_.m.lockedInt, "\n")
+		throw("internal lockOSThread error")
+	}
+	gfput(_p_, gp)
+	if locked {
+		// The goroutine may have locked this thread because
+		// it put it in an unusual kernel state. Kill it
+		// rather than returning it to the thread pool.
+
+		// Return to mstart, which will release the P and exit
+		// the thread.
+		if GOOS != "plan9" { // See golang.org/issue/22227.
+			gogo(&_g_.m.g0.sched)
+		} else {
+			// Clear lockedExt on plan9 since we may end up re-using
+			// this thread.
+			_g_.m.lockedExt = 0
+		}
+	}
+	schedule()
+}
+
+// save updates getg().sched to refer to pc and sp so that a following
+// gogo will restore pc and sp.
+//
+// save must not have write barriers because invoking a write barrier
+// can clobber getg().sched.
+//
+//go:nosplit
+//go:nowritebarrierrec
+func save(pc, sp uintptr) {
+	_g_ := getg()
+
+	if _g_ == _g_.m.g0 || _g_ == _g_.m.gsignal {
+		// m.g0.sched is special and must describe the context
+		// for exiting the thread. mstart1 writes to it directly.
+		// m.gsignal.sched should not be used at all.
+		// This check makes sure save calls do not accidentally
+		// run in contexts where they'd write to system g's.
+		throw("save on system g not allowed")
+	}
+
+	_g_.sched.pc = pc
+	_g_.sched.sp = sp
+	_g_.sched.lr = 0
+	_g_.sched.ret = 0
+	// We need to ensure ctxt is zero, but can't have a write
+	// barrier here. However, it should always already be zero.
+	// Assert that.
+	if _g_.sched.ctxt != nil {
+		badctxt()
+	}
+}
+
+// The goroutine g is about to enter a system call.
+// Record that it's not using the cpu anymore.
+// This is called only from the go syscall library and cgocall,
+// not from the low-level system calls used by the runtime.
+//
+// Entersyscall cannot split the stack: the save must
+// make g->sched refer to the caller's stack segment, because
+// entersyscall is going to return immediately after.
+//
+// Nothing entersyscall calls can split the stack either.
+// We cannot safely move the stack during an active call to syscall,
+// because we do not know which of the uintptr arguments are
+// really pointers (back into the stack).
+// In practice, this means that we make the fast path run through
+// entersyscall doing no-split things, and the slow path has to use systemstack
+// to run bigger things on the system stack.
+//
+// reentersyscall is the entry point used by cgo callbacks, where explicitly
+// saved SP and PC are restored. This is needed when exitsyscall will be called
+// from a function further up in the call stack than the parent, as g->syscallsp
+// must always point to a valid stack frame. entersyscall below is the normal
+// entry point for syscalls, which obtains the SP and PC from the caller.
+//
+// Syscall tracing:
+// At the start of a syscall we emit traceGoSysCall to capture the stack trace.
+// If the syscall does not block, that is it, we do not emit any other events.
+// If the syscall blocks (that is, P is retaken), retaker emits traceGoSysBlock;
+// when syscall returns we emit traceGoSysExit and when the goroutine starts running
+// (potentially instantly, if exitsyscallfast returns true) we emit traceGoStart.
+// To ensure that traceGoSysExit is emitted strictly after traceGoSysBlock,
+// we remember current value of syscalltick in m (_g_.m.syscalltick = _g_.m.p.ptr().syscalltick),
+// whoever emits traceGoSysBlock increments p.syscalltick afterwards;
+// and we wait for the increment before emitting traceGoSysExit.
+// Note that the increment is done even if tracing is not enabled,
+// because tracing can be enabled in the middle of syscall. We don't want the wait to hang.
+//
+//go:nosplit
+func reentersyscall(pc, sp uintptr) {
+	_g_ := getg()
+
+	// Disable preemption because during this function g is in Gsyscall status,
+	// but can have inconsistent g->sched, do not let GC observe it.
+	_g_.m.locks++
+
+	// Entersyscall must not call any function that might split/grow the stack.
+	// (See details in comment above.)
+	// Catch calls that might, by replacing the stack guard with something that
+	// will trip any stack check and leaving a flag to tell newstack to die.
+	_g_.stackguard0 = stackPreempt
+	_g_.throwsplit = true
+
+	// Leave SP around for GC and traceback.
+	save(pc, sp)
+	_g_.syscallsp = sp
+	_g_.syscallpc = pc
+	casgstatus(_g_, _Grunning, _Gsyscall)
+	if _g_.syscallsp < _g_.stack.lo || _g_.stack.hi < _g_.syscallsp {
+		systemstack(func() {
+			print("entersyscall inconsistent ", hex(_g_.syscallsp), " [", hex(_g_.stack.lo), ",", hex(_g_.stack.hi), "]\n")
+			throw("entersyscall")
+		})
+	}
+
+	if trace.enabled {
+		systemstack(traceGoSysCall)
+		// systemstack itself clobbers g.sched.{pc,sp} and we might
+		// need them later when the G is genuinely blocked in a
+		// syscall
+		save(pc, sp)
+	}
+
+	if atomic.Load(&sched.sysmonwait) != 0 {
+		systemstack(entersyscall_sysmon)
+		save(pc, sp)
+	}
+
+	if _g_.m.p.ptr().runSafePointFn != 0 {
+		// runSafePointFn may stack split if run on this stack
+		systemstack(runSafePointFn)
+		save(pc, sp)
+	}
+
+	_g_.m.syscalltick = _g_.m.p.ptr().syscalltick
+	_g_.sysblocktraced = true
+	pp := _g_.m.p.ptr()
+	pp.m = 0
+	_g_.m.oldp.set(pp)
+	_g_.m.p = 0
+	atomic.Store(&pp.status, _Psyscall)
+	if sched.gcwaiting != 0 {
+		systemstack(entersyscall_gcwait)
+		save(pc, sp)
+	}
+
+	_g_.m.locks--
+}
+
+// Standard syscall entry used by the go syscall library and normal cgo calls.
+//
+// This is exported via linkname to assembly in the syscall package and x/sys.
+//
+//go:nosplit
+//go:linkname entersyscall
+func entersyscall() {
+	reentersyscall(getcallerpc(), getcallersp())
+}
+
+func entersyscall_sysmon() {
+	lock(&sched.lock)
+	if atomic.Load(&sched.sysmonwait) != 0 {
+		atomic.Store(&sched.sysmonwait, 0)
+		notewakeup(&sched.sysmonnote)
+	}
+	unlock(&sched.lock)
+}
+
+func entersyscall_gcwait() {
+	_g_ := getg()
+	_p_ := _g_.m.oldp.ptr()
+
+	lock(&sched.lock)
+	if sched.stopwait > 0 && atomic.Cas(&_p_.status, _Psyscall, _Pgcstop) {
+		if trace.enabled {
+			traceGoSysBlock(_p_)
+			traceProcStop(_p_)
+		}
+		_p_.syscalltick++
+		if sched.stopwait--; sched.stopwait == 0 {
+			notewakeup(&sched.stopnote)
+		}
+	}
+	unlock(&sched.lock)
+}
+
+// The same as entersyscall(), but with a hint that the syscall is blocking.
+//
+//go:nosplit
+func entersyscallblock() {
+	_g_ := getg()
+
+	_g_.m.locks++ // see comment in entersyscall
+	_g_.throwsplit = true
+	_g_.stackguard0 = stackPreempt // see comment in entersyscall
+	_g_.m.syscalltick = _g_.m.p.ptr().syscalltick
+	_g_.sysblocktraced = true
+	_g_.m.p.ptr().syscalltick++
+
+	// Leave SP around for GC and traceback.
+	pc := getcallerpc()
+	sp := getcallersp()
+	save(pc, sp)
+	_g_.syscallsp = _g_.sched.sp
+	_g_.syscallpc = _g_.sched.pc
+	if _g_.syscallsp < _g_.stack.lo || _g_.stack.hi < _g_.syscallsp {
+		sp1 := sp
+		sp2 := _g_.sched.sp
+		sp3 := _g_.syscallsp
+		systemstack(func() {
+			print("entersyscallblock inconsistent ", hex(sp1), " ", hex(sp2), " ", hex(sp3), " [", hex(_g_.stack.lo), ",", hex(_g_.stack.hi), "]\n")
+			throw("entersyscallblock")
+		})
+	}
+	casgstatus(_g_, _Grunning, _Gsyscall)
+	if _g_.syscallsp < _g_.stack.lo || _g_.stack.hi < _g_.syscallsp {
+		systemstack(func() {
+			print("entersyscallblock inconsistent ", hex(sp), " ", hex(_g_.sched.sp), " ", hex(_g_.syscallsp), " [", hex(_g_.stack.lo), ",", hex(_g_.stack.hi), "]\n")
+			throw("entersyscallblock")
+		})
+	}
+
+	systemstack(entersyscallblock_handoff)
+
+	// Resave for traceback during blocked call.
+	save(getcallerpc(), getcallersp())
+
+	_g_.m.locks--
+}
+
+func entersyscallblock_handoff() {
+	if trace.enabled {
+		traceGoSysCall()
+		traceGoSysBlock(getg().m.p.ptr())
+	}
+	handoffp(releasep())
+}
+
+// The goroutine g exited its system call.
+// Arrange for it to run on a cpu again.
+// This is called only from the go syscall library, not
+// from the low-level system calls used by the runtime.
+//
+// Write barriers are not allowed because our P may have been stolen.
+//
+// This is exported via linkname to assembly in the syscall package.
+//
+//go:nosplit
+//go:nowritebarrierrec
+//go:linkname exitsyscall
+func exitsyscall() {
+	_g_ := getg()
+
+	_g_.m.locks++ // see comment in entersyscall
+	if getcallersp() > _g_.syscallsp {
+		throw("exitsyscall: syscall frame is no longer valid")
+	}
+
+	_g_.waitsince = 0
+	oldp := _g_.m.oldp.ptr()
+	_g_.m.oldp = 0
+	if exitsyscallfast(oldp) {
+		// When exitsyscallfast returns success, we have a P so can now use
+		// write barriers
+		if goroutineProfile.active {
+			// Make sure that gp has had its stack written out to the goroutine
+			// profile, exactly as it was when the goroutine profiler first
+			// stopped the world.
+			systemstack(func() {
+				tryRecordGoroutineProfileWB(_g_)
+			})
+		}
+		if trace.enabled {
+			if oldp != _g_.m.p.ptr() || _g_.m.syscalltick != _g_.m.p.ptr().syscalltick {
+				systemstack(traceGoStart)
+			}
+		}
+		// There's a cpu for us, so we can run.
+		_g_.m.p.ptr().syscalltick++
+		// We need to cas the status and scan before resuming...
+		casgstatus(_g_, _Gsyscall, _Grunning)
+
+		// Garbage collector isn't running (since we are),
+		// so okay to clear syscallsp.
+		_g_.syscallsp = 0
+		_g_.m.locks--
+		if _g_.preempt {
+			// restore the preemption request in case we've cleared it in newstack
+			_g_.stackguard0 = stackPreempt
+		} else {
+			// otherwise restore the real _StackGuard, we've spoiled it in entersyscall/entersyscallblock
+			_g_.stackguard0 = _g_.stack.lo + _StackGuard
+		}
+		_g_.throwsplit = false
+
+		if sched.disable.user && !schedEnabled(_g_) {
+			// Scheduling of this goroutine is disabled.
+			Gosched()
+		}
+
+		return
+	}
+
+	_g_.sysexitticks = 0
+	if trace.enabled {
+		// Wait till traceGoSysBlock event is emitted.
+		// This ensures consistency of the trace (the goroutine is started after it is blocked).
+		for oldp != nil && oldp.syscalltick == _g_.m.syscalltick {
+			osyield()
+		}
+		// We can't trace syscall exit right now because we don't have a P.
+		// Tracing code can invoke write barriers that cannot run without a P.
+		// So instead we remember the syscall exit time and emit the event
+		// in execute when we have a P.
+		_g_.sysexitticks = cputicks()
+	}
+
+	_g_.m.locks--
+
+	// Call the scheduler.
+	mcall(exitsyscall0)
+
+	// Scheduler returned, so we're allowed to run now.
+	// Delete the syscallsp information that we left for
+	// the garbage collector during the system call.
+	// Must wait until now because until gosched returns
+	// we don't know for sure that the garbage collector
+	// is not running.
+	_g_.syscallsp = 0
+	_g_.m.p.ptr().syscalltick++
+	_g_.throwsplit = false
+}
+
+//go:nosplit
+func exitsyscallfast(oldp *p) bool {
+	_g_ := getg()
+
+	// Freezetheworld sets stopwait but does not retake P's.
+	if sched.stopwait == freezeStopWait {
+		return false
+	}
+
+	// Try to re-acquire the last P.
+	if oldp != nil && oldp.status == _Psyscall && atomic.Cas(&oldp.status, _Psyscall, _Pidle) {
+		// There's a cpu for us, so we can run.
+		wirep(oldp)
+		exitsyscallfast_reacquired()
+		return true
+	}
+
+	// Try to get any other idle P.
+	if sched.pidle != 0 {
+		var ok bool
+		systemstack(func() {
+			ok = exitsyscallfast_pidle()
+			if ok && trace.enabled {
+				if oldp != nil {
+					// Wait till traceGoSysBlock event is emitted.
+					// This ensures consistency of the trace (the goroutine is started after it is blocked).
+					for oldp.syscalltick == _g_.m.syscalltick {
+						osyield()
+					}
+				}
+				traceGoSysExit(0)
+			}
+		})
+		if ok {
+			return true
+		}
+	}
+	return false
+}
+
+// exitsyscallfast_reacquired is the exitsyscall path on which this G
+// has successfully reacquired the P it was running on before the
+// syscall.
+//
+//go:nosplit
+func exitsyscallfast_reacquired() {
+	_g_ := getg()
+	if _g_.m.syscalltick != _g_.m.p.ptr().syscalltick {
+		if trace.enabled {
+			// The p was retaken and then enter into syscall again (since _g_.m.syscalltick has changed).
+			// traceGoSysBlock for this syscall was already emitted,
+			// but here we effectively retake the p from the new syscall running on the same p.
+			systemstack(func() {
+				// Denote blocking of the new syscall.
+				traceGoSysBlock(_g_.m.p.ptr())
+				// Denote completion of the current syscall.
+				traceGoSysExit(0)
+			})
+		}
+		_g_.m.p.ptr().syscalltick++
+	}
+}
+
+func exitsyscallfast_pidle() bool {
+	lock(&sched.lock)
+	_p_, _ := pidleget(0)
+	if _p_ != nil && atomic.Load(&sched.sysmonwait) != 0 {
+		atomic.Store(&sched.sysmonwait, 0)
+		notewakeup(&sched.sysmonnote)
+	}
+	unlock(&sched.lock)
+	if _p_ != nil {
+		acquirep(_p_)
+		return true
+	}
+	return false
+}
+
+// exitsyscall slow path on g0.
+// Failed to acquire P, enqueue gp as runnable.
+//
+// Called via mcall, so gp is the calling g from this M.
+//
+//go:nowritebarrierrec
+func exitsyscall0(gp *g) {
+	casgstatus(gp, _Gsyscall, _Grunnable)
+	dropg()
+	lock(&sched.lock)
+	var _p_ *p
+	if schedEnabled(gp) {
+		_p_, _ = pidleget(0)
+	}
+	var locked bool
+	if _p_ == nil {
+		globrunqput(gp)
+
+		// Below, we stoplockedm if gp is locked. globrunqput releases
+		// ownership of gp, so we must check if gp is locked prior to
+		// committing the release by unlocking sched.lock, otherwise we
+		// could race with another M transitioning gp from unlocked to
+		// locked.
+		locked = gp.lockedm != 0
+	} else if atomic.Load(&sched.sysmonwait) != 0 {
+		atomic.Store(&sched.sysmonwait, 0)
+		notewakeup(&sched.sysmonnote)
+	}
+	unlock(&sched.lock)
+	if _p_ != nil {
+		acquirep(_p_)
+		execute(gp, false) // Never returns.
+	}
+	if locked {
+		// Wait until another thread schedules gp and so m again.
+		//
+		// N.B. lockedm must be this M, as this g was running on this M
+		// before entersyscall.
+		stoplockedm()
+		execute(gp, false) // Never returns.
+	}
+	stopm()
+	schedule() // Never returns.
+}
+
+// Called from syscall package before fork.
+//
+//go:linkname syscall_runtime_BeforeFork syscall.runtime_BeforeFork
+//go:nosplit
+func syscall_runtime_BeforeFork() {
+	gp := getg().m.curg
+
+	// Block signals during a fork, so that the child does not run
+	// a signal handler before exec if a signal is sent to the process
+	// group. See issue #18600.
+	gp.m.locks++
+	sigsave(&gp.m.sigmask)
+	sigblock(false)
+
+	// This function is called before fork in syscall package.
+	// Code between fork and exec must not allocate memory nor even try to grow stack.
+	// Here we spoil g->_StackGuard to reliably detect any attempts to grow stack.
+	// runtime_AfterFork will undo this in parent process, but not in child.
+	gp.stackguard0 = stackFork
+}
+
+// Called from syscall package after fork in parent.
+//
+//go:linkname syscall_runtime_AfterFork syscall.runtime_AfterFork
+//go:nosplit
+func syscall_runtime_AfterFork() {
+	gp := getg().m.curg
+
+	// See the comments in beforefork.
+	gp.stackguard0 = gp.stack.lo + _StackGuard
+
+	msigrestore(gp.m.sigmask)
+
+	gp.m.locks--
+}
+
+// inForkedChild is true while manipulating signals in the child process.
+// This is used to avoid calling libc functions in case we are using vfork.
+var inForkedChild bool
+
+// Called from syscall package after fork in child.
+// It resets non-sigignored signals to the default handler, and
+// restores the signal mask in preparation for the exec.
+//
+// Because this might be called during a vfork, and therefore may be
+// temporarily sharing address space with the parent process, this must
+// not change any global variables or calling into C code that may do so.
+//
+//go:linkname syscall_runtime_AfterForkInChild syscall.runtime_AfterForkInChild
+//go:nosplit
+//go:nowritebarrierrec
+func syscall_runtime_AfterForkInChild() {
+	// It's OK to change the global variable inForkedChild here
+	// because we are going to change it back. There is no race here,
+	// because if we are sharing address space with the parent process,
+	// then the parent process can not be running concurrently.
+	inForkedChild = true
+
+	clearSignalHandlers()
+
+	// When we are the child we are the only thread running,
+	// so we know that nothing else has changed gp.m.sigmask.
+	msigrestore(getg().m.sigmask)
+
+	inForkedChild = false
+}
+
+// pendingPreemptSignals is the number of preemption signals
+// that have been sent but not received. This is only used on Darwin.
+// For #41702.
+var pendingPreemptSignals uint32
+
+// Called from syscall package before Exec.
+//
+//go:linkname syscall_runtime_BeforeExec syscall.runtime_BeforeExec
+func syscall_runtime_BeforeExec() {
+	// Prevent thread creation during exec.
+	execLock.lock()
+
+	// On Darwin, wait for all pending preemption signals to
+	// be received. See issue #41702.
+	if GOOS == "darwin" || GOOS == "ios" {
+		for int32(atomic.Load(&pendingPreemptSignals)) > 0 {
+			osyield()
+		}
+	}
+}
+
+// Called from syscall package after Exec.
+//
+//go:linkname syscall_runtime_AfterExec syscall.runtime_AfterExec
+func syscall_runtime_AfterExec() {
+	execLock.unlock()
+}
+
+// Allocate a new g, with a stack big enough for stacksize bytes.
+func malg(stacksize int32) *g {
+	newg := new(g)
+	if stacksize >= 0 {
+		stacksize = round2(_StackSystem + stacksize)
+		systemstack(func() {
+			newg.stack = stackalloc(uint32(stacksize))
+		})
+		newg.stackguard0 = newg.stack.lo + _StackGuard
+		newg.stackguard1 = ^uintptr(0)
+		// Clear the bottom word of the stack. We record g
+		// there on gsignal stack during VDSO on ARM and ARM64.
+		*(*uintptr)(unsafe.Pointer(newg.stack.lo)) = 0
+	}
+	return newg
+}
+
+// Create a new g running fn.
+// Put it on the queue of g's waiting to run.
+// The compiler turns a go statement into a call to this.
+func newproc(fn *funcval) {
+	gp := getg()
+	pc := getcallerpc()
+	systemstack(func() {
+		newg := newproc1(fn, gp, pc)
+
+		_p_ := getg().m.p.ptr()
+		runqput(_p_, newg, true)
+
+		if mainStarted {
+			wakep()
+		}
+	})
+}
+
+// Create a new g in state _Grunnable, starting at fn. callerpc is the
+// address of the go statement that created this. The caller is responsible
+// for adding the new g to the scheduler.
+func newproc1(fn *funcval, callergp *g, callerpc uintptr) *g {
+	_g_ := getg()
+
+	if fn == nil {
+		fatal("go of nil func value")
+	}
+	acquirem() // disable preemption because it can be holding p in a local var
+
+	_p_ := _g_.m.p.ptr()
+	newg := gfget(_p_)
+	if newg == nil {
+		newg = malg(_StackMin)
+		casgstatus(newg, _Gidle, _Gdead)
+		allgadd(newg) // publishes with a g->status of Gdead so GC scanner doesn't look at uninitialized stack.
+	}
+	if newg.stack.hi == 0 {
+		throw("newproc1: newg missing stack")
+	}
+
+	if readgstatus(newg) != _Gdead {
+		throw("newproc1: new g is not Gdead")
+	}
+
+	totalSize := uintptr(4*goarch.PtrSize + sys.MinFrameSize) // extra space in case of reads slightly beyond frame
+	totalSize = alignUp(totalSize, sys.StackAlign)
+	sp := newg.stack.hi - totalSize
+	spArg := sp
+	if usesLR {
+		// caller's LR
+		*(*uintptr)(unsafe.Pointer(sp)) = 0
+		prepGoExitFrame(sp)
+		spArg += sys.MinFrameSize
+	}
+
+	memclrNoHeapPointers(unsafe.Pointer(&newg.sched), unsafe.Sizeof(newg.sched))
+	newg.sched.sp = sp
+	newg.stktopsp = sp
+	newg.sched.pc = abi.FuncPCABI0(goexit) + sys.PCQuantum // +PCQuantum so that previous instruction is in same function
+	newg.sched.g = guintptr(unsafe.Pointer(newg))
+	gostartcallfn(&newg.sched, fn)
+	newg.gopc = callerpc
+	newg.ancestors = saveAncestors(callergp)
+	newg.startpc = fn.fn
+	if isSystemGoroutine(newg, false) {
+		atomic.Xadd(&sched.ngsys, +1)
+	} else {
+		// Only user goroutines inherit pprof labels.
+		if _g_.m.curg != nil {
+			newg.labels = _g_.m.curg.labels
+		}
+		if goroutineProfile.active {
+			// A concurrent goroutine profile is running. It should include
+			// exactly the set of goroutines that were alive when the goroutine
+			// profiler first stopped the world. That does not include newg, so
+			// mark it as not needing a profile before transitioning it from
+			// _Gdead.
+			newg.goroutineProfiled.Store(goroutineProfileSatisfied)
+		}
+	}
+	// Track initial transition?
+	newg.trackingSeq = uint8(fastrand())
+	if newg.trackingSeq%gTrackingPeriod == 0 {
+		newg.tracking = true
+	}
+	casgstatus(newg, _Gdead, _Grunnable)
+	gcController.addScannableStack(_p_, int64(newg.stack.hi-newg.stack.lo))
+
+	if _p_.goidcache == _p_.goidcacheend {
+		// Sched.goidgen is the last allocated id,
+		// this batch must be [sched.goidgen+1, sched.goidgen+GoidCacheBatch].
+		// At startup sched.goidgen=0, so main goroutine receives goid=1.
+		_p_.goidcache = atomic.Xadd64(&sched.goidgen, _GoidCacheBatch)
+		_p_.goidcache -= _GoidCacheBatch - 1
+		_p_.goidcacheend = _p_.goidcache + _GoidCacheBatch
+	}
+	newg.goid = int64(_p_.goidcache)
+	_p_.goidcache++
+	if raceenabled {
+		newg.racectx = racegostart(callerpc)
+		if newg.labels != nil {
+			// See note in proflabel.go on labelSync's role in synchronizing
+			// with the reads in the signal handler.
+			racereleasemergeg(newg, unsafe.Pointer(&labelSync))
+		}
+	}
+	if trace.enabled {
+		traceGoCreate(newg, newg.startpc)
+	}
+	releasem(_g_.m)
+
+	return newg
+}
+
+// saveAncestors copies previous ancestors of the given caller g and
+// includes infor for the current caller into a new set of tracebacks for
+// a g being created.
+func saveAncestors(callergp *g) *[]ancestorInfo {
+	// Copy all prior info, except for the root goroutine (goid 0).
+	if debug.tracebackancestors <= 0 || callergp.goid == 0 {
+		return nil
+	}
+	var callerAncestors []ancestorInfo
+	if callergp.ancestors != nil {
+		callerAncestors = *callergp.ancestors
+	}
+	n := int32(len(callerAncestors)) + 1
+	if n > debug.tracebackancestors {
+		n = debug.tracebackancestors
+	}
+	ancestors := make([]ancestorInfo, n)
+	copy(ancestors[1:], callerAncestors)
+
+	var pcs [_TracebackMaxFrames]uintptr
+	npcs := gcallers(callergp, 0, pcs[:])
+	ipcs := make([]uintptr, npcs)
+	copy(ipcs, pcs[:])
+	ancestors[0] = ancestorInfo{
+		pcs:  ipcs,
+		goid: callergp.goid,
+		gopc: callergp.gopc,
+	}
+
+	ancestorsp := new([]ancestorInfo)
+	*ancestorsp = ancestors
+	return ancestorsp
+}
+
+// Put on gfree list.
+// If local list is too long, transfer a batch to the global list.
+func gfput(_p_ *p, gp *g) {
+	if readgstatus(gp) != _Gdead {
+		throw("gfput: bad status (not Gdead)")
+	}
+
+	stksize := gp.stack.hi - gp.stack.lo
+
+	if stksize != uintptr(startingStackSize) {
+		// non-standard stack size - free it.
+		stackfree(gp.stack)
+		gp.stack.lo = 0
+		gp.stack.hi = 0
+		gp.stackguard0 = 0
+	}
+
+	_p_.gFree.push(gp)
+	_p_.gFree.n++
+	if _p_.gFree.n >= 64 {
+		var (
+			inc      int32
+			stackQ   gQueue
+			noStackQ gQueue
+		)
+		for _p_.gFree.n >= 32 {
+			gp = _p_.gFree.pop()
+			_p_.gFree.n--
+			if gp.stack.lo == 0 {
+				noStackQ.push(gp)
+			} else {
+				stackQ.push(gp)
+			}
+			inc++
+		}
+		lock(&sched.gFree.lock)
+		sched.gFree.noStack.pushAll(noStackQ)
+		sched.gFree.stack.pushAll(stackQ)
+		sched.gFree.n += inc
+		unlock(&sched.gFree.lock)
+	}
+}
+
+// Get from gfree list.
+// If local list is empty, grab a batch from global list.
+func gfget(_p_ *p) *g {
+retry:
+	if _p_.gFree.empty() && (!sched.gFree.stack.empty() || !sched.gFree.noStack.empty()) {
+		lock(&sched.gFree.lock)
+		// Move a batch of free Gs to the P.
+		for _p_.gFree.n < 32 {
+			// Prefer Gs with stacks.
+			gp := sched.gFree.stack.pop()
+			if gp == nil {
+				gp = sched.gFree.noStack.pop()
+				if gp == nil {
+					break
+				}
+			}
+			sched.gFree.n--
+			_p_.gFree.push(gp)
+			_p_.gFree.n++
+		}
+		unlock(&sched.gFree.lock)
+		goto retry
+	}
+	gp := _p_.gFree.pop()
+	if gp == nil {
+		return nil
+	}
+	_p_.gFree.n--
+	if gp.stack.lo != 0 && gp.stack.hi-gp.stack.lo != uintptr(startingStackSize) {
+		// Deallocate old stack. We kept it in gfput because it was the
+		// right size when the goroutine was put on the free list, but
+		// the right size has changed since then.
+		systemstack(func() {
+			stackfree(gp.stack)
+			gp.stack.lo = 0
+			gp.stack.hi = 0
+			gp.stackguard0 = 0
+		})
+	}
+	if gp.stack.lo == 0 {
+		// Stack was deallocated in gfput or just above. Allocate a new one.
+		systemstack(func() {
+			gp.stack = stackalloc(startingStackSize)
+		})
+		gp.stackguard0 = gp.stack.lo + _StackGuard
+	} else {
+		if raceenabled {
+			racemalloc(unsafe.Pointer(gp.stack.lo), gp.stack.hi-gp.stack.lo)
+		}
+		if msanenabled {
+			msanmalloc(unsafe.Pointer(gp.stack.lo), gp.stack.hi-gp.stack.lo)
+		}
+		if asanenabled {
+			asanunpoison(unsafe.Pointer(gp.stack.lo), gp.stack.hi-gp.stack.lo)
+		}
+	}
+	return gp
+}
+
+// Purge all cached G's from gfree list to the global list.
+func gfpurge(_p_ *p) {
+	var (
+		inc      int32
+		stackQ   gQueue
+		noStackQ gQueue
+	)
+	for !_p_.gFree.empty() {
+		gp := _p_.gFree.pop()
+		_p_.gFree.n--
+		if gp.stack.lo == 0 {
+			noStackQ.push(gp)
+		} else {
+			stackQ.push(gp)
+		}
+		inc++
+	}
+	lock(&sched.gFree.lock)
+	sched.gFree.noStack.pushAll(noStackQ)
+	sched.gFree.stack.pushAll(stackQ)
+	sched.gFree.n += inc
+	unlock(&sched.gFree.lock)
+}
+
+// Breakpoint executes a breakpoint trap.
+func Breakpoint() {
+	breakpoint()
+}
+
+// dolockOSThread is called by LockOSThread and lockOSThread below
+// after they modify m.locked. Do not allow preemption during this call,
+// or else the m might be different in this function than in the caller.
+//
+//go:nosplit
+func dolockOSThread() {
+	if GOARCH == "wasm" {
+		return // no threads on wasm yet
+	}
+	_g_ := getg()
+	_g_.m.lockedg.set(_g_)
+	_g_.lockedm.set(_g_.m)
+}
+
+//go:nosplit
+
+// LockOSThread wires the calling goroutine to its current operating system thread.
+// The calling goroutine will always execute in that thread,
+// and no other goroutine will execute in it,
+// until the calling goroutine has made as many calls to
+// UnlockOSThread as to LockOSThread.
+// If the calling goroutine exits without unlocking the thread,
+// the thread will be terminated.
+//
+// All init functions are run on the startup thread. Calling LockOSThread
+// from an init function will cause the main function to be invoked on
+// that thread.
+//
+// A goroutine should call LockOSThread before calling OS services or
+// non-Go library functions that depend on per-thread state.
+func LockOSThread() {
+	if atomic.Load(&newmHandoff.haveTemplateThread) == 0 && GOOS != "plan9" {
+		// If we need to start a new thread from the locked
+		// thread, we need the template thread. Start it now
+		// while we're in a known-good state.
+		startTemplateThread()
+	}
+	_g_ := getg()
+	_g_.m.lockedExt++
+	if _g_.m.lockedExt == 0 {
+		_g_.m.lockedExt--
+		panic("LockOSThread nesting overflow")
+	}
+	dolockOSThread()
+}
+
+//go:nosplit
+func lockOSThread() {
+	getg().m.lockedInt++
+	dolockOSThread()
+}
+
+// dounlockOSThread is called by UnlockOSThread and unlockOSThread below
+// after they update m->locked. Do not allow preemption during this call,
+// or else the m might be in different in this function than in the caller.
+//
+//go:nosplit
+func dounlockOSThread() {
+	if GOARCH == "wasm" {
+		return // no threads on wasm yet
+	}
+	_g_ := getg()
+	if _g_.m.lockedInt != 0 || _g_.m.lockedExt != 0 {
+		return
+	}
+	_g_.m.lockedg = 0
+	_g_.lockedm = 0
+}
+
+//go:nosplit
+
+// UnlockOSThread undoes an earlier call to LockOSThread.
+// If this drops the number of active LockOSThread calls on the
+// calling goroutine to zero, it unwires the calling goroutine from
+// its fixed operating system thread.
+// If there are no active LockOSThread calls, this is a no-op.
+//
+// Before calling UnlockOSThread, the caller must ensure that the OS
+// thread is suitable for running other goroutines. If the caller made
+// any permanent changes to the state of the thread that would affect
+// other goroutines, it should not call this function and thus leave
+// the goroutine locked to the OS thread until the goroutine (and
+// hence the thread) exits.
+func UnlockOSThread() {
+	_g_ := getg()
+	if _g_.m.lockedExt == 0 {
+		return
+	}
+	_g_.m.lockedExt--
+	dounlockOSThread()
+}
+
+//go:nosplit
+func unlockOSThread() {
+	_g_ := getg()
+	if _g_.m.lockedInt == 0 {
+		systemstack(badunlockosthread)
+	}
+	_g_.m.lockedInt--
+	dounlockOSThread()
+}
+
+func badunlockosthread() {
+	throw("runtime: internal error: misuse of lockOSThread/unlockOSThread")
+}
+
+func gcount() int32 {
+	n := int32(atomic.Loaduintptr(&allglen)) - sched.gFree.n - int32(atomic.Load(&sched.ngsys))
+	for _, _p_ := range allp {
+		n -= _p_.gFree.n
+	}
+
+	// All these variables can be changed concurrently, so the result can be inconsistent.
+	// But at least the current goroutine is running.
+	if n < 1 {
+		n = 1
+	}
+	return n
+}
+
+func mcount() int32 {
+	return int32(sched.mnext - sched.nmfreed)
+}
+
+var prof struct {
+	signalLock uint32
+	hz         int32
+}
+
+func _System()                    { _System() }
+func _ExternalCode()              { _ExternalCode() }
+func _LostExternalCode()          { _LostExternalCode() }
+func _GC()                        { _GC() }
+func _LostSIGPROFDuringAtomic64() { _LostSIGPROFDuringAtomic64() }
+func _VDSO()                      { _VDSO() }
+
+// Called if we receive a SIGPROF signal.
+// Called by the signal handler, may run during STW.
+//
+//go:nowritebarrierrec
+func sigprof(pc, sp, lr uintptr, gp *g, mp *m) {
+	if prof.hz == 0 {
+		return
+	}
+
+	// If mp.profilehz is 0, then profiling is not enabled for this thread.
+	// We must check this to avoid a deadlock between setcpuprofilerate
+	// and the call to cpuprof.add, below.
+	if mp != nil && mp.profilehz == 0 {
+		return
+	}
+
+	// On mips{,le}/arm, 64bit atomics are emulated with spinlocks, in
+	// runtime/internal/atomic. If SIGPROF arrives while the program is inside
+	// the critical section, it creates a deadlock (when writing the sample).
+	// As a workaround, create a counter of SIGPROFs while in critical section
+	// to store the count, and pass it to sigprof.add() later when SIGPROF is
+	// received from somewhere else (with _LostSIGPROFDuringAtomic64 as pc).
+	if GOARCH == "mips" || GOARCH == "mipsle" || GOARCH == "arm" {
+		if f := findfunc(pc); f.valid() {
+			if hasPrefix(funcname(f), "runtime/internal/atomic") {
+				cpuprof.lostAtomic++
+				return
+			}
+		}
+		if GOARCH == "arm" && goarm < 7 && GOOS == "linux" && pc&0xffff0000 == 0xffff0000 {
+			// runtime/internal/atomic functions call into kernel
+			// helpers on arm < 7. See
+			// runtime/internal/atomic/sys_linux_arm.s.
+			cpuprof.lostAtomic++
+			return
+		}
+	}
+
+	// Profiling runs concurrently with GC, so it must not allocate.
+	// Set a trap in case the code does allocate.
+	// Note that on windows, one thread takes profiles of all the
+	// other threads, so mp is usually not getg().m.
+	// In fact mp may not even be stopped.
+	// See golang.org/issue/17165.
+	getg().m.mallocing++
+
+	var stk [maxCPUProfStack]uintptr
+	n := 0
+	if mp.ncgo > 0 && mp.curg != nil && mp.curg.syscallpc != 0 && mp.curg.syscallsp != 0 {
+		cgoOff := 0
+		// Check cgoCallersUse to make sure that we are not
+		// interrupting other code that is fiddling with
+		// cgoCallers.  We are running in a signal handler
+		// with all signals blocked, so we don't have to worry
+		// about any other code interrupting us.
+		if atomic.Load(&mp.cgoCallersUse) == 0 && mp.cgoCallers != nil && mp.cgoCallers[0] != 0 {
+			for cgoOff < len(mp.cgoCallers) && mp.cgoCallers[cgoOff] != 0 {
+				cgoOff++
+			}
+			copy(stk[:], mp.cgoCallers[:cgoOff])
+			mp.cgoCallers[0] = 0
+		}
+
+		// Collect Go stack that leads to the cgo call.
+		n = gentraceback(mp.curg.syscallpc, mp.curg.syscallsp, 0, mp.curg, 0, &stk[cgoOff], len(stk)-cgoOff, nil, nil, 0)
+		if n > 0 {
+			n += cgoOff
+		}
+	} else {
+		n = gentraceback(pc, sp, lr, gp, 0, &stk[0], len(stk), nil, nil, _TraceTrap|_TraceJumpStack)
+	}
+
+	if n <= 0 {
+		// Normal traceback is impossible or has failed.
+		// See if it falls into several common cases.
+		n = 0
+		if usesLibcall() && mp.libcallg != 0 && mp.libcallpc != 0 && mp.libcallsp != 0 {
+			// Libcall, i.e. runtime syscall on windows.
+			// Collect Go stack that leads to the call.
+			n = gentraceback(mp.libcallpc, mp.libcallsp, 0, mp.libcallg.ptr(), 0, &stk[0], len(stk), nil, nil, 0)
+		}
+		if n == 0 && mp != nil && mp.vdsoSP != 0 {
+			n = gentraceback(mp.vdsoPC, mp.vdsoSP, 0, gp, 0, &stk[0], len(stk), nil, nil, _TraceTrap|_TraceJumpStack)
+		}
+		if n == 0 {
+			// If all of the above has failed, account it against abstract "System" or "GC".
+			n = 2
+			if inVDSOPage(pc) {
+				pc = abi.FuncPCABIInternal(_VDSO) + sys.PCQuantum
+			} else if pc > firstmoduledata.etext {
+				// "ExternalCode" is better than "etext".
+				pc = abi.FuncPCABIInternal(_ExternalCode) + sys.PCQuantum
+			}
+			stk[0] = pc
+			if mp.preemptoff != "" {
+				stk[1] = abi.FuncPCABIInternal(_GC) + sys.PCQuantum
+			} else {
+				stk[1] = abi.FuncPCABIInternal(_System) + sys.PCQuantum
+			}
+		}
+	}
+
+	if prof.hz != 0 {
+		// Note: it can happen on Windows that we interrupted a system thread
+		// with no g, so gp could nil. The other nil checks are done out of
+		// caution, but not expected to be nil in practice.
+		var tagPtr *unsafe.Pointer
+		if gp != nil && gp.m != nil && gp.m.curg != nil {
+			tagPtr = &gp.m.curg.labels
+		}
+		cpuprof.add(tagPtr, stk[:n])
+
+		gprof := gp
+		var pp *p
+		if gp != nil && gp.m != nil {
+			if gp.m.curg != nil {
+				gprof = gp.m.curg
+			}
+			pp = gp.m.p.ptr()
+		}
+		traceCPUSample(gprof, pp, stk[:n])
+	}
+	getg().m.mallocing--
+}
+
+// setcpuprofilerate sets the CPU profiling rate to hz times per second.
+// If hz <= 0, setcpuprofilerate turns off CPU profiling.
+func setcpuprofilerate(hz int32) {
+	// Force sane arguments.
+	if hz < 0 {
+		hz = 0
+	}
+
+	// Disable preemption, otherwise we can be rescheduled to another thread
+	// that has profiling enabled.
+	_g_ := getg()
+	_g_.m.locks++
+
+	// Stop profiler on this thread so that it is safe to lock prof.
+	// if a profiling signal came in while we had prof locked,
+	// it would deadlock.
+	setThreadCPUProfiler(0)
+
+	for !atomic.Cas(&prof.signalLock, 0, 1) {
+		osyield()
+	}
+	if prof.hz != hz {
+		setProcessCPUProfiler(hz)
+		prof.hz = hz
+	}
+	atomic.Store(&prof.signalLock, 0)
+
+	lock(&sched.lock)
+	sched.profilehz = hz
+	unlock(&sched.lock)
+
+	if hz != 0 {
+		setThreadCPUProfiler(hz)
+	}
+
+	_g_.m.locks--
+}
+
+// init initializes pp, which may be a freshly allocated p or a
+// previously destroyed p, and transitions it to status _Pgcstop.
+func (pp *p) init(id int32) {
+	pp.id = id
+	pp.status = _Pgcstop
+	pp.sudogcache = pp.sudogbuf[:0]
+	pp.deferpool = pp.deferpoolbuf[:0]
+	pp.wbBuf.reset()
+	if pp.mcache == nil {
+		if id == 0 {
+			if mcache0 == nil {
+				throw("missing mcache?")
+			}
+			// Use the bootstrap mcache0. Only one P will get
+			// mcache0: the one with ID 0.
+			pp.mcache = mcache0
+		} else {
+			pp.mcache = allocmcache()
+		}
+	}
+	if raceenabled && pp.raceprocctx == 0 {
+		if id == 0 {
+			pp.raceprocctx = raceprocctx0
+			raceprocctx0 = 0 // bootstrap
+		} else {
+			pp.raceprocctx = raceproccreate()
+		}
+	}
+	lockInit(&pp.timersLock, lockRankTimers)
+
+	// This P may get timers when it starts running. Set the mask here
+	// since the P may not go through pidleget (notably P 0 on startup).
+	timerpMask.set(id)
+	// Similarly, we may not go through pidleget before this P starts
+	// running if it is P 0 on startup.
+	idlepMask.clear(id)
+}
+
+// destroy releases all of the resources associated with pp and
+// transitions it to status _Pdead.
+//
+// sched.lock must be held and the world must be stopped.
+func (pp *p) destroy() {
+	assertLockHeld(&sched.lock)
+	assertWorldStopped()
+
+	// Move all runnable goroutines to the global queue
+	for pp.runqhead != pp.runqtail {
+		// Pop from tail of local queue
+		pp.runqtail--
+		gp := pp.runq[pp.runqtail%uint32(len(pp.runq))].ptr()
+		// Push onto head of global queue
+		globrunqputhead(gp)
+	}
+	if pp.runnext != 0 {
+		globrunqputhead(pp.runnext.ptr())
+		pp.runnext = 0
+	}
+	if len(pp.timers) > 0 {
+		plocal := getg().m.p.ptr()
+		// The world is stopped, but we acquire timersLock to
+		// protect against sysmon calling timeSleepUntil.
+		// This is the only case where we hold the timersLock of
+		// more than one P, so there are no deadlock concerns.
+		lock(&plocal.timersLock)
+		lock(&pp.timersLock)
+		moveTimers(plocal, pp.timers)
+		pp.timers = nil
+		pp.numTimers = 0
+		pp.deletedTimers = 0
+		atomic.Store64(&pp.timer0When, 0)
+		unlock(&pp.timersLock)
+		unlock(&plocal.timersLock)
+	}
+	// Flush p's write barrier buffer.
+	if gcphase != _GCoff {
+		wbBufFlush1(pp)
+		pp.gcw.dispose()
+	}
+	for i := range pp.sudogbuf {
+		pp.sudogbuf[i] = nil
+	}
+	pp.sudogcache = pp.sudogbuf[:0]
+	for j := range pp.deferpoolbuf {
+		pp.deferpoolbuf[j] = nil
+	}
+	pp.deferpool = pp.deferpoolbuf[:0]
+	systemstack(func() {
+		for i := 0; i < pp.mspancache.len; i++ {
+			// Safe to call since the world is stopped.
+			mheap_.spanalloc.free(unsafe.Pointer(pp.mspancache.buf[i]))
+		}
+		pp.mspancache.len = 0
+		lock(&mheap_.lock)
+		pp.pcache.flush(&mheap_.pages)
+		unlock(&mheap_.lock)
+	})
+	freemcache(pp.mcache)
+	pp.mcache = nil
+	gfpurge(pp)
+	traceProcFree(pp)
+	if raceenabled {
+		if pp.timerRaceCtx != 0 {
+			// The race detector code uses a callback to fetch
+			// the proc context, so arrange for that callback
+			// to see the right thing.
+			// This hack only works because we are the only
+			// thread running.
+			mp := getg().m
+			phold := mp.p.ptr()
+			mp.p.set(pp)
+
+			racectxend(pp.timerRaceCtx)
+			pp.timerRaceCtx = 0
+
+			mp.p.set(phold)
+		}
+		raceprocdestroy(pp.raceprocctx)
+		pp.raceprocctx = 0
+	}
+	pp.gcAssistTime = 0
+	pp.status = _Pdead
+}
+
+// Change number of processors.
+//
+// sched.lock must be held, and the world must be stopped.
+//
+// gcworkbufs must not be being modified by either the GC or the write barrier
+// code, so the GC must not be running if the number of Ps actually changes.
+//
+// Returns list of Ps with local work, they need to be scheduled by the caller.
+func procresize(nprocs int32) *p {
+	assertLockHeld(&sched.lock)
+	assertWorldStopped()
+
+	old := gomaxprocs
+	if old < 0 || nprocs <= 0 {
+		throw("procresize: invalid arg")
+	}
+	if trace.enabled {
+		traceGomaxprocs(nprocs)
+	}
+
+	// update statistics
+	now := nanotime()
+	if sched.procresizetime != 0 {
+		sched.totaltime += int64(old) * (now - sched.procresizetime)
+	}
+	sched.procresizetime = now
+
+	maskWords := (nprocs + 31) / 32
+
+	// Grow allp if necessary.
+	if nprocs > int32(len(allp)) {
+		// Synchronize with retake, which could be running
+		// concurrently since it doesn't run on a P.
+		lock(&allpLock)
+		if nprocs <= int32(cap(allp)) {
+			allp = allp[:nprocs]
+		} else {
+			nallp := make([]*p, nprocs)
+			// Copy everything up to allp's cap so we
+			// never lose old allocated Ps.
+			copy(nallp, allp[:cap(allp)])
+			allp = nallp
+		}
+
+		if maskWords <= int32(cap(idlepMask)) {
+			idlepMask = idlepMask[:maskWords]
+			timerpMask = timerpMask[:maskWords]
+		} else {
+			nidlepMask := make([]uint32, maskWords)
+			// No need to copy beyond len, old Ps are irrelevant.
+			copy(nidlepMask, idlepMask)
+			idlepMask = nidlepMask
+
+			ntimerpMask := make([]uint32, maskWords)
+			copy(ntimerpMask, timerpMask)
+			timerpMask = ntimerpMask
+		}
+		unlock(&allpLock)
+	}
+
+	// initialize new P's
+	for i := old; i < nprocs; i++ {
+		pp := allp[i]
+		if pp == nil {
+			pp = new(p)
+		}
+		pp.init(i)
+		atomicstorep(unsafe.Pointer(&allp[i]), unsafe.Pointer(pp))
+	}
+
+	_g_ := getg()
+	if _g_.m.p != 0 && _g_.m.p.ptr().id < nprocs {
+		// continue to use the current P
+		_g_.m.p.ptr().status = _Prunning
+		_g_.m.p.ptr().mcache.prepareForSweep()
+	} else {
+		// release the current P and acquire allp[0].
+		//
+		// We must do this before destroying our current P
+		// because p.destroy itself has write barriers, so we
+		// need to do that from a valid P.
+		if _g_.m.p != 0 {
+			if trace.enabled {
+				// Pretend that we were descheduled
+				// and then scheduled again to keep
+				// the trace sane.
+				traceGoSched()
+				traceProcStop(_g_.m.p.ptr())
+			}
+			_g_.m.p.ptr().m = 0
+		}
+		_g_.m.p = 0
+		p := allp[0]
+		p.m = 0
+		p.status = _Pidle
+		acquirep(p)
+		if trace.enabled {
+			traceGoStart()
+		}
+	}
+
+	// g.m.p is now set, so we no longer need mcache0 for bootstrapping.
+	mcache0 = nil
+
+	// release resources from unused P's
+	for i := nprocs; i < old; i++ {
+		p := allp[i]
+		p.destroy()
+		// can't free P itself because it can be referenced by an M in syscall
+	}
+
+	// Trim allp.
+	if int32(len(allp)) != nprocs {
+		lock(&allpLock)
+		allp = allp[:nprocs]
+		idlepMask = idlepMask[:maskWords]
+		timerpMask = timerpMask[:maskWords]
+		unlock(&allpLock)
+	}
+
+	var runnablePs *p
+	for i := nprocs - 1; i >= 0; i-- {
+		p := allp[i]
+		if _g_.m.p.ptr() == p {
+			continue
+		}
+		p.status = _Pidle
+		if runqempty(p) {
+			pidleput(p, now)
+		} else {
+			p.m.set(mget())
+			p.link.set(runnablePs)
+			runnablePs = p
+		}
+	}
+	stealOrder.reset(uint32(nprocs))
+	var int32p *int32 = &gomaxprocs // make compiler check that gomaxprocs is an int32
+	atomic.Store((*uint32)(unsafe.Pointer(int32p)), uint32(nprocs))
+	if old != nprocs {
+		// Notify the limiter that the amount of procs has changed.
+		gcCPULimiter.resetCapacity(now, nprocs)
+	}
+	return runnablePs
+}
+
+// Associate p and the current m.
+//
+// This function is allowed to have write barriers even if the caller
+// isn't because it immediately acquires _p_.
+//
+//go:yeswritebarrierrec
+func acquirep(_p_ *p) {
+	// Do the part that isn't allowed to have write barriers.
+	wirep(_p_)
+
+	// Have p; write barriers now allowed.
+
+	// Perform deferred mcache flush before this P can allocate
+	// from a potentially stale mcache.
+	_p_.mcache.prepareForSweep()
+
+	if trace.enabled {
+		traceProcStart()
+	}
+}
+
+// wirep is the first step of acquirep, which actually associates the
+// current M to _p_. This is broken out so we can disallow write
+// barriers for this part, since we don't yet have a P.
+//
+//go:nowritebarrierrec
+//go:nosplit
+func wirep(_p_ *p) {
+	_g_ := getg()
+
+	if _g_.m.p != 0 {
+		throw("wirep: already in go")
+	}
+	if _p_.m != 0 || _p_.status != _Pidle {
+		id := int64(0)
+		if _p_.m != 0 {
+			id = _p_.m.ptr().id
+		}
+		print("wirep: p->m=", _p_.m, "(", id, ") p->status=", _p_.status, "\n")
+		throw("wirep: invalid p state")
+	}
+	_g_.m.p.set(_p_)
+	_p_.m.set(_g_.m)
+	_p_.status = _Prunning
+}
+
+// Disassociate p and the current m.
+func releasep() *p {
+	_g_ := getg()
+
+	if _g_.m.p == 0 {
+		throw("releasep: invalid arg")
+	}
+	_p_ := _g_.m.p.ptr()
+	if _p_.m.ptr() != _g_.m || _p_.status != _Prunning {
+		print("releasep: m=", _g_.m, " m->p=", _g_.m.p.ptr(), " p->m=", hex(_p_.m), " p->status=", _p_.status, "\n")
+		throw("releasep: invalid p state")
+	}
+	if trace.enabled {
+		traceProcStop(_g_.m.p.ptr())
+	}
+	_g_.m.p = 0
+	_p_.m = 0
+	_p_.status = _Pidle
+	return _p_
+}
+
+func incidlelocked(v int32) {
+	lock(&sched.lock)
+	sched.nmidlelocked += v
+	if v > 0 {
+		checkdead()
+	}
+	unlock(&sched.lock)
+}
+
+// Check for deadlock situation.
+// The check is based on number of running M's, if 0 -> deadlock.
+// sched.lock must be held.
+func checkdead() {
+	assertLockHeld(&sched.lock)
+
+	// For -buildmode=c-shared or -buildmode=c-archive it's OK if
+	// there are no running goroutines. The calling program is
+	// assumed to be running.
+	if islibrary || isarchive {
+		return
+	}
+
+	// If we are dying because of a signal caught on an already idle thread,
+	// freezetheworld will cause all running threads to block.
+	// And runtime will essentially enter into deadlock state,
+	// except that there is a thread that will call exit soon.
+	if panicking > 0 {
+		return
+	}
+
+	// If we are not running under cgo, but we have an extra M then account
+	// for it. (It is possible to have an extra M on Windows without cgo to
+	// accommodate callbacks created by syscall.NewCallback. See issue #6751
+	// for details.)
+	var run0 int32
+	if !iscgo && cgoHasExtraM {
+		mp := lockextra(true)
+		haveExtraM := extraMCount > 0
+		unlockextra(mp)
+		if haveExtraM {
+			run0 = 1
+		}
+	}
+
+	run := mcount() - sched.nmidle - sched.nmidlelocked - sched.nmsys
+	if run > run0 {
+		return
+	}
+	if run < 0 {
+		print("runtime: checkdead: nmidle=", sched.nmidle, " nmidlelocked=", sched.nmidlelocked, " mcount=", mcount(), " nmsys=", sched.nmsys, "\n")
+		throw("checkdead: inconsistent counts")
+	}
+
+	grunning := 0
+	forEachG(func(gp *g) {
+		if isSystemGoroutine(gp, false) {
+			return
+		}
+		s := readgstatus(gp)
+		switch s &^ _Gscan {
+		case _Gwaiting,
+			_Gpreempted:
+			grunning++
+		case _Grunnable,
+			_Grunning,
+			_Gsyscall:
+			print("runtime: checkdead: find g ", gp.goid, " in status ", s, "\n")
+			throw("checkdead: runnable g")
+		}
+	})
+	if grunning == 0 { // possible if main goroutine calls runtime·Goexit()
+		unlock(&sched.lock) // unlock so that GODEBUG=scheddetail=1 doesn't hang
+		fatal("no goroutines (main called runtime.Goexit) - deadlock!")
+	}
+
+	// Maybe jump time forward for playground.
+	if faketime != 0 {
+		if when := timeSleepUntil(); when < maxWhen {
+			faketime = when
+
+			// Start an M to steal the timer.
+			pp, _ := pidleget(faketime)
+			if pp == nil {
+				// There should always be a free P since
+				// nothing is running.
+				throw("checkdead: no p for timer")
+			}
+			mp := mget()
+			if mp == nil {
+				// There should always be a free M since
+				// nothing is running.
+				throw("checkdead: no m for timer")
+			}
+			// M must be spinning to steal. We set this to be
+			// explicit, but since this is the only M it would
+			// become spinning on its own anyways.
+			atomic.Xadd(&sched.nmspinning, 1)
+			mp.spinning = true
+			mp.nextp.set(pp)
+			notewakeup(&mp.park)
+			return
+		}
+	}
+
+	// There are no goroutines running, so we can look at the P's.
+	for _, _p_ := range allp {
+		if len(_p_.timers) > 0 {
+			return
+		}
+	}
+
+	unlock(&sched.lock) // unlock so that GODEBUG=scheddetail=1 doesn't hang
+	fatal("all goroutines are asleep - deadlock!")
+}
+
+// forcegcperiod is the maximum time in nanoseconds between garbage
+// collections. If we go this long without a garbage collection, one
+// is forced to run.
+//
+// This is a variable for testing purposes. It normally doesn't change.
+var forcegcperiod int64 = 2 * 60 * 1e9
+
+// needSysmonWorkaround is true if the workaround for
+// golang.org/issue/42515 is needed on NetBSD.
+var needSysmonWorkaround bool = false
+
+// Always runs without a P, so write barriers are not allowed.
+//
+//go:nowritebarrierrec
+func sysmon() {
+	lock(&sched.lock)
+	sched.nmsys++
+	checkdead()
+	unlock(&sched.lock)
+
+	lasttrace := int64(0)
+	idle := 0 // how many cycles in succession we had not wokeup somebody
+	delay := uint32(0)
+
+	for {
+		if idle == 0 { // start with 20us sleep...
+			delay = 20
+		} else if idle > 50 { // start doubling the sleep after 1ms...
+			delay *= 2
+		}
+		if delay > 10*1000 { // up to 10ms
+			delay = 10 * 1000
+		}
+		usleep(delay)
+
+		// sysmon should not enter deep sleep if schedtrace is enabled so that
+		// it can print that information at the right time.
+		//
+		// It should also not enter deep sleep if there are any active P's so
+		// that it can retake P's from syscalls, preempt long running G's, and
+		// poll the network if all P's are busy for long stretches.
+		//
+		// It should wakeup from deep sleep if any P's become active either due
+		// to exiting a syscall or waking up due to a timer expiring so that it
+		// can resume performing those duties. If it wakes from a syscall it
+		// resets idle and delay as a bet that since it had retaken a P from a
+		// syscall before, it may need to do it again shortly after the
+		// application starts work again. It does not reset idle when waking
+		// from a timer to avoid adding system load to applications that spend
+		// most of their time sleeping.
+		now := nanotime()
+		if debug.schedtrace <= 0 && (sched.gcwaiting != 0 || atomic.Load(&sched.npidle) == uint32(gomaxprocs)) {
+			lock(&sched.lock)
+			if atomic.Load(&sched.gcwaiting) != 0 || atomic.Load(&sched.npidle) == uint32(gomaxprocs) {
+				syscallWake := false
+				next := timeSleepUntil()
+				if next > now {
+					atomic.Store(&sched.sysmonwait, 1)
+					unlock(&sched.lock)
+					// Make wake-up period small enough
+					// for the sampling to be correct.
+					sleep := forcegcperiod / 2
+					if next-now < sleep {
+						sleep = next - now
+					}
+					shouldRelax := sleep >= osRelaxMinNS
+					if shouldRelax {
+						osRelax(true)
+					}
+					syscallWake = notetsleep(&sched.sysmonnote, sleep)
+					if shouldRelax {
+						osRelax(false)
+					}
+					lock(&sched.lock)
+					atomic.Store(&sched.sysmonwait, 0)
+					noteclear(&sched.sysmonnote)
+				}
+				if syscallWake {
+					idle = 0
+					delay = 20
+				}
+			}
+			unlock(&sched.lock)
+		}
+
+		lock(&sched.sysmonlock)
+		// Update now in case we blocked on sysmonnote or spent a long time
+		// blocked on schedlock or sysmonlock above.
+		now = nanotime()
+
+		// trigger libc interceptors if needed
+		if *cgo_yield != nil {
+			asmcgocall(*cgo_yield, nil)
+		}
+		// poll network if not polled for more than 10ms
+		lastpoll := int64(atomic.Load64(&sched.lastpoll))
+		if netpollinited() && lastpoll != 0 && lastpoll+10*1000*1000 < now {
+			atomic.Cas64(&sched.lastpoll, uint64(lastpoll), uint64(now))
+			list := netpoll(0) // non-blocking - returns list of goroutines
+			if !list.empty() {
+				// Need to decrement number of idle locked M's
+				// (pretending that one more is running) before injectglist.
+				// Otherwise it can lead to the following situation:
+				// injectglist grabs all P's but before it starts M's to run the P's,
+				// another M returns from syscall, finishes running its G,
+				// observes that there is no work to do and no other running M's
+				// and reports deadlock.
+				incidlelocked(-1)
+				injectglist(&list)
+				incidlelocked(1)
+			}
+		}
+		if GOOS == "netbsd" && needSysmonWorkaround {
+			// netpoll is responsible for waiting for timer
+			// expiration, so we typically don't have to worry
+			// about starting an M to service timers. (Note that
+			// sleep for timeSleepUntil above simply ensures sysmon
+			// starts running again when that timer expiration may
+			// cause Go code to run again).
+			//
+			// However, netbsd has a kernel bug that sometimes
+			// misses netpollBreak wake-ups, which can lead to
+			// unbounded delays servicing timers. If we detect this
+			// overrun, then startm to get something to handle the
+			// timer.
+			//
+			// See issue 42515 and
+			// https://gnats.netbsd.org/cgi-bin/query-pr-single.pl?number=50094.
+			if next := timeSleepUntil(); next < now {
+				startm(nil, false)
+			}
+		}
+		if scavenger.sysmonWake.Load() != 0 {
+			// Kick the scavenger awake if someone requested it.
+			scavenger.wake()
+		}
+		// retake P's blocked in syscalls
+		// and preempt long running G's
+		if retake(now) != 0 {
+			idle = 0
+		} else {
+			idle++
+		}
+		// check if we need to force a GC
+		if t := (gcTrigger{kind: gcTriggerTime, now: now}); t.test() && atomic.Load(&forcegc.idle) != 0 {
+			lock(&forcegc.lock)
+			forcegc.idle = 0
+			var list gList
+			list.push(forcegc.g)
+			injectglist(&list)
+			unlock(&forcegc.lock)
+		}
+		if debug.schedtrace > 0 && lasttrace+int64(debug.schedtrace)*1000000 <= now {
+			lasttrace = now
+			schedtrace(debug.scheddetail > 0)
+		}
+		unlock(&sched.sysmonlock)
+	}
+}
+
+type sysmontick struct {
+	schedtick   uint32
+	schedwhen   int64
+	syscalltick uint32
+	syscallwhen int64
+}
+
+// forcePreemptNS is the time slice given to a G before it is
+// preempted.
+const forcePreemptNS = 10 * 1000 * 1000 // 10ms
+
+func retake(now int64) uint32 {
+	n := 0
+	// Prevent allp slice changes. This lock will be completely
+	// uncontended unless we're already stopping the world.
+	lock(&allpLock)
+	// We can't use a range loop over allp because we may
+	// temporarily drop the allpLock. Hence, we need to re-fetch
+	// allp each time around the loop.
+	for i := 0; i < len(allp); i++ {
+		_p_ := allp[i]
+		if _p_ == nil {
+			// This can happen if procresize has grown
+			// allp but not yet created new Ps.
+			continue
+		}
+		pd := &_p_.sysmontick
+		s := _p_.status
+		sysretake := false
+		if s == _Prunning || s == _Psyscall {
+			// Preempt G if it's running for too long.
+			t := int64(_p_.schedtick)
+			if int64(pd.schedtick) != t {
+				pd.schedtick = uint32(t)
+				pd.schedwhen = now
+			} else if pd.schedwhen+forcePreemptNS <= now {
+				preemptone(_p_)
+				// In case of syscall, preemptone() doesn't
+				// work, because there is no M wired to P.
+				sysretake = true
+			}
+		}
+		if s == _Psyscall {
+			// Retake P from syscall if it's there for more than 1 sysmon tick (at least 20us).
+			t := int64(_p_.syscalltick)
+			if !sysretake && int64(pd.syscalltick) != t {
+				pd.syscalltick = uint32(t)
+				pd.syscallwhen = now
+				continue
+			}
+			// On the one hand we don't want to retake Ps if there is no other work to do,
+			// but on the other hand we want to retake them eventually
+			// because they can prevent the sysmon thread from deep sleep.
+			if runqempty(_p_) && atomic.Load(&sched.nmspinning)+atomic.Load(&sched.npidle) > 0 && pd.syscallwhen+10*1000*1000 > now {
+				continue
+			}
+			// Drop allpLock so we can take sched.lock.
+			unlock(&allpLock)
+			// Need to decrement number of idle locked M's
+			// (pretending that one more is running) before the CAS.
+			// Otherwise the M from which we retake can exit the syscall,
+			// increment nmidle and report deadlock.
+			incidlelocked(-1)
+			if atomic.Cas(&_p_.status, s, _Pidle) {
+				if trace.enabled {
+					traceGoSysBlock(_p_)
+					traceProcStop(_p_)
+				}
+				n++
+				_p_.syscalltick++
+				handoffp(_p_)
+			}
+			incidlelocked(1)
+			lock(&allpLock)
+		}
+	}
+	unlock(&allpLock)
+	return uint32(n)
+}
+
+// Tell all goroutines that they have been preempted and they should stop.
+// This function is purely best-effort. It can fail to inform a goroutine if a
+// processor just started running it.
+// No locks need to be held.
+// Returns true if preemption request was issued to at least one goroutine.
+func preemptall() bool {
+	res := false
+	for _, _p_ := range allp {
+		if _p_.status != _Prunning {
+			continue
+		}
+		if preemptone(_p_) {
+			res = true
+		}
+	}
+	return res
+}
+
+// Tell the goroutine running on processor P to stop.
+// This function is purely best-effort. It can incorrectly fail to inform the
+// goroutine. It can inform the wrong goroutine. Even if it informs the
+// correct goroutine, that goroutine might ignore the request if it is
+// simultaneously executing newstack.
+// No lock needs to be held.
+// Returns true if preemption request was issued.
+// The actual preemption will happen at some point in the future
+// and will be indicated by the gp->status no longer being
+// Grunning
+func preemptone(_p_ *p) bool {
+	mp := _p_.m.ptr()
+	if mp == nil || mp == getg().m {
+		return false
+	}
+	gp := mp.curg
+	if gp == nil || gp == mp.g0 {
+		return false
+	}
+
+	gp.preempt = true
+
+	// Every call in a goroutine checks for stack overflow by
+	// comparing the current stack pointer to gp->stackguard0.
+	// Setting gp->stackguard0 to StackPreempt folds
+	// preemption into the normal stack overflow check.
+	gp.stackguard0 = stackPreempt
+
+	// Request an async preemption of this P.
+	if preemptMSupported && debug.asyncpreemptoff == 0 {
+		_p_.preempt = true
+		preemptM(mp)
+	}
+
+	return true
+}
+
+var starttime int64
+
+func schedtrace(detailed bool) {
+	now := nanotime()
+	if starttime == 0 {
+		starttime = now
+	}
+
+	lock(&sched.lock)
+	print("SCHED ", (now-starttime)/1e6, "ms: gomaxprocs=", gomaxprocs, " idleprocs=", sched.npidle, " threads=", mcount(), " spinningthreads=", sched.nmspinning, " idlethreads=", sched.nmidle, " runqueue=", sched.runqsize)
+	if detailed {
+		print(" gcwaiting=", sched.gcwaiting, " nmidlelocked=", sched.nmidlelocked, " stopwait=", sched.stopwait, " sysmonwait=", sched.sysmonwait, "\n")
+	}
+	// We must be careful while reading data from P's, M's and G's.
+	// Even if we hold schedlock, most data can be changed concurrently.
+	// E.g. (p->m ? p->m->id : -1) can crash if p->m changes from non-nil to nil.
+	for i, _p_ := range allp {
+		mp := _p_.m.ptr()
+		h := atomic.Load(&_p_.runqhead)
+		t := atomic.Load(&_p_.runqtail)
+		if detailed {
+			id := int64(-1)
+			if mp != nil {
+				id = mp.id
+			}
+			print("  P", i, ": status=", _p_.status, " schedtick=", _p_.schedtick, " syscalltick=", _p_.syscalltick, " m=", id, " runqsize=", t-h, " gfreecnt=", _p_.gFree.n, " timerslen=", len(_p_.timers), "\n")
+		} else {
+			// In non-detailed mode format lengths of per-P run queues as:
+			// [len1 len2 len3 len4]
+			print(" ")
+			if i == 0 {
+				print("[")
+			}
+			print(t - h)
+			if i == len(allp)-1 {
+				print("]\n")
+			}
+		}
+	}
+
+	if !detailed {
+		unlock(&sched.lock)
+		return
+	}
+
+	for mp := allm; mp != nil; mp = mp.alllink {
+		_p_ := mp.p.ptr()
+		gp := mp.curg
+		lockedg := mp.lockedg.ptr()
+		id1 := int32(-1)
+		if _p_ != nil {
+			id1 = _p_.id
+		}
+		id2 := int64(-1)
+		if gp != nil {
+			id2 = gp.goid
+		}
+		id3 := int64(-1)
+		if lockedg != nil {
+			id3 = lockedg.goid
+		}
+		print("  M", mp.id, ": p=", id1, " curg=", id2, " mallocing=", mp.mallocing, " throwing=", mp.throwing, " preemptoff=", mp.preemptoff, ""+" locks=", mp.locks, " dying=", mp.dying, " spinning=", mp.spinning, " blocked=", mp.blocked, " lockedg=", id3, "\n")
+	}
+
+	forEachG(func(gp *g) {
+		mp := gp.m
+		lockedm := gp.lockedm.ptr()
+		id1 := int64(-1)
+		if mp != nil {
+			id1 = mp.id
+		}
+		id2 := int64(-1)
+		if lockedm != nil {
+			id2 = lockedm.id
+		}
+		print("  G", gp.goid, ": status=", readgstatus(gp), "(", gp.waitreason.String(), ") m=", id1, " lockedm=", id2, "\n")
+	})
+	unlock(&sched.lock)
+}
+
+// schedEnableUser enables or disables the scheduling of user
+// goroutines.
+//
+// This does not stop already running user goroutines, so the caller
+// should first stop the world when disabling user goroutines.
+func schedEnableUser(enable bool) {
+	lock(&sched.lock)
+	if sched.disable.user == !enable {
+		unlock(&sched.lock)
+		return
+	}
+	sched.disable.user = !enable
+	if enable {
+		n := sched.disable.n
+		sched.disable.n = 0
+		globrunqputbatch(&sched.disable.runnable, n)
+		unlock(&sched.lock)
+		for ; n != 0 && sched.npidle != 0; n-- {
+			startm(nil, false)
+		}
+	} else {
+		unlock(&sched.lock)
+	}
+}
+
+// schedEnabled reports whether gp should be scheduled. It returns
+// false is scheduling of gp is disabled.
+//
+// sched.lock must be held.
+func schedEnabled(gp *g) bool {
+	assertLockHeld(&sched.lock)
+
+	if sched.disable.user {
+		return isSystemGoroutine(gp, true)
+	}
+	return true
+}
+
+// Put mp on midle list.
+// sched.lock must be held.
+// May run during STW, so write barriers are not allowed.
+//
+//go:nowritebarrierrec
+func mput(mp *m) {
+	assertLockHeld(&sched.lock)
+
+	mp.schedlink = sched.midle
+	sched.midle.set(mp)
+	sched.nmidle++
+	checkdead()
+}
+
+// Try to get an m from midle list.
+// sched.lock must be held.
+// May run during STW, so write barriers are not allowed.
+//
+//go:nowritebarrierrec
+func mget() *m {
+	assertLockHeld(&sched.lock)
+
+	mp := sched.midle.ptr()
+	if mp != nil {
+		sched.midle = mp.schedlink
+		sched.nmidle--
+	}
+	return mp
+}
+
+// Put gp on the global runnable queue.
+// sched.lock must be held.
+// May run during STW, so write barriers are not allowed.
+//
+//go:nowritebarrierrec
+func globrunqput(gp *g) {
+	assertLockHeld(&sched.lock)
+
+	sched.runq.pushBack(gp)
+	sched.runqsize++
+}
+
+// Put gp at the head of the global runnable queue.
+// sched.lock must be held.
+// May run during STW, so write barriers are not allowed.
+//
+//go:nowritebarrierrec
+func globrunqputhead(gp *g) {
+	assertLockHeld(&sched.lock)
+
+	sched.runq.push(gp)
+	sched.runqsize++
+}
+
+// Put a batch of runnable goroutines on the global runnable queue.
+// This clears *batch.
+// sched.lock must be held.
+// May run during STW, so write barriers are not allowed.
+//
+//go:nowritebarrierrec
+func globrunqputbatch(batch *gQueue, n int32) {
+	assertLockHeld(&sched.lock)
+
+	sched.runq.pushBackAll(*batch)
+	sched.runqsize += n
+	*batch = gQueue{}
+}
+
+// Try get a batch of G's from the global runnable queue.
+// sched.lock must be held.
+func globrunqget(_p_ *p, max int32) *g {
+	assertLockHeld(&sched.lock)
+
+	if sched.runqsize == 0 {
+		return nil
+	}
+
+	n := sched.runqsize/gomaxprocs + 1
+	if n > sched.runqsize {
+		n = sched.runqsize
+	}
+	if max > 0 && n > max {
+		n = max
+	}
+	if n > int32(len(_p_.runq))/2 {
+		n = int32(len(_p_.runq)) / 2
+	}
+
+	sched.runqsize -= n
+
+	gp := sched.runq.pop()
+	n--
+	for ; n > 0; n-- {
+		gp1 := sched.runq.pop()
+		runqput(_p_, gp1, false)
+	}
+	return gp
+}
+
+// pMask is an atomic bitstring with one bit per P.
+type pMask []uint32
+
+// read returns true if P id's bit is set.
+func (p pMask) read(id uint32) bool {
+	word := id / 32
+	mask := uint32(1) << (id % 32)
+	return (atomic.Load(&p[word]) & mask) != 0
+}
+
+// set sets P id's bit.
+func (p pMask) set(id int32) {
+	word := id / 32
+	mask := uint32(1) << (id % 32)
+	atomic.Or(&p[word], mask)
+}
+
+// clear clears P id's bit.
+func (p pMask) clear(id int32) {
+	word := id / 32
+	mask := uint32(1) << (id % 32)
+	atomic.And(&p[word], ^mask)
+}
+
+// updateTimerPMask clears pp's timer mask if it has no timers on its heap.
+//
+// Ideally, the timer mask would be kept immediately consistent on any timer
+// operations. Unfortunately, updating a shared global data structure in the
+// timer hot path adds too much overhead in applications frequently switching
+// between no timers and some timers.
+//
+// As a compromise, the timer mask is updated only on pidleget / pidleput. A
+// running P (returned by pidleget) may add a timer at any time, so its mask
+// must be set. An idle P (passed to pidleput) cannot add new timers while
+// idle, so if it has no timers at that time, its mask may be cleared.
+//
+// Thus, we get the following effects on timer-stealing in findrunnable:
+//
+//   - Idle Ps with no timers when they go idle are never checked in findrunnable
+//     (for work- or timer-stealing; this is the ideal case).
+//   - Running Ps must always be checked.
+//   - Idle Ps whose timers are stolen must continue to be checked until they run
+//     again, even after timer expiration.
+//
+// When the P starts running again, the mask should be set, as a timer may be
+// added at any time.
+//
+// TODO(prattmic): Additional targeted updates may improve the above cases.
+// e.g., updating the mask when stealing a timer.
+func updateTimerPMask(pp *p) {
+	if atomic.Load(&pp.numTimers) > 0 {
+		return
+	}
+
+	// Looks like there are no timers, however another P may transiently
+	// decrement numTimers when handling a timerModified timer in
+	// checkTimers. We must take timersLock to serialize with these changes.
+	lock(&pp.timersLock)
+	if atomic.Load(&pp.numTimers) == 0 {
+		timerpMask.clear(pp.id)
+	}
+	unlock(&pp.timersLock)
+}
+
+// pidleput puts p on the _Pidle list. now must be a relatively recent call
+// to nanotime or zero. Returns now or the current time if now was zero.
+//
+// This releases ownership of p. Once sched.lock is released it is no longer
+// safe to use p.
+//
+// sched.lock must be held.
+//
+// May run during STW, so write barriers are not allowed.
+//
+//go:nowritebarrierrec
+func pidleput(_p_ *p, now int64) int64 {
+	assertLockHeld(&sched.lock)
+
+	if !runqempty(_p_) {
+		throw("pidleput: P has non-empty run queue")
+	}
+	if now == 0 {
+		now = nanotime()
+	}
+	updateTimerPMask(_p_) // clear if there are no timers.
+	idlepMask.set(_p_.id)
+	_p_.link = sched.pidle
+	sched.pidle.set(_p_)
+	atomic.Xadd(&sched.npidle, 1)
+	if !_p_.limiterEvent.start(limiterEventIdle, now) {
+		throw("must be able to track idle limiter event")
+	}
+	return now
+}
+
+// pidleget tries to get a p from the _Pidle list, acquiring ownership.
+//
+// sched.lock must be held.
+//
+// May run during STW, so write barriers are not allowed.
+//
+//go:nowritebarrierrec
+func pidleget(now int64) (*p, int64) {
+	assertLockHeld(&sched.lock)
+
+	_p_ := sched.pidle.ptr()
+	if _p_ != nil {
+		// Timer may get added at any time now.
+		if now == 0 {
+			now = nanotime()
+		}
+		timerpMask.set(_p_.id)
+		idlepMask.clear(_p_.id)
+		sched.pidle = _p_.link
+		atomic.Xadd(&sched.npidle, -1)
+		_p_.limiterEvent.stop(limiterEventIdle, now)
+	}
+	return _p_, now
+}
+
+// runqempty reports whether _p_ has no Gs on its local run queue.
+// It never returns true spuriously.
+func runqempty(_p_ *p) bool {
+	// Defend against a race where 1) _p_ has G1 in runqnext but runqhead == runqtail,
+	// 2) runqput on _p_ kicks G1 to the runq, 3) runqget on _p_ empties runqnext.
+	// Simply observing that runqhead == runqtail and then observing that runqnext == nil
+	// does not mean the queue is empty.
+	for {
+		head := atomic.Load(&_p_.runqhead)
+		tail := atomic.Load(&_p_.runqtail)
+		runnext := atomic.Loaduintptr((*uintptr)(unsafe.Pointer(&_p_.runnext)))
+		if tail == atomic.Load(&_p_.runqtail) {
+			return head == tail && runnext == 0
+		}
+	}
+}
+
+// To shake out latent assumptions about scheduling order,
+// we introduce some randomness into scheduling decisions
+// when running with the race detector.
+// The need for this was made obvious by changing the
+// (deterministic) scheduling order in Go 1.5 and breaking
+// many poorly-written tests.
+// With the randomness here, as long as the tests pass
+// consistently with -race, they shouldn't have latent scheduling
+// assumptions.
+const randomizeScheduler = raceenabled
+
+// runqput tries to put g on the local runnable queue.
+// If next is false, runqput adds g to the tail of the runnable queue.
+// If next is true, runqput puts g in the _p_.runnext slot.
+// If the run queue is full, runnext puts g on the global queue.
+// Executed only by the owner P.
+func runqput(_p_ *p, gp *g, next bool) {
+	if randomizeScheduler && next && fastrandn(2) == 0 {
+		next = false
+	}
+
+	if next {
+	retryNext:
+		oldnext := _p_.runnext
+		if !_p_.runnext.cas(oldnext, guintptr(unsafe.Pointer(gp))) {
+			goto retryNext
+		}
+		if oldnext == 0 {
+			return
+		}
+		// Kick the old runnext out to the regular run queue.
+		gp = oldnext.ptr()
+	}
+
+retry:
+	h := atomic.LoadAcq(&_p_.runqhead) // load-acquire, synchronize with consumers
+	t := _p_.runqtail
+	if t-h < uint32(len(_p_.runq)) {
+		_p_.runq[t%uint32(len(_p_.runq))].set(gp)
+		atomic.StoreRel(&_p_.runqtail, t+1) // store-release, makes the item available for consumption
+		return
+	}
+	if runqputslow(_p_, gp, h, t) {
+		return
+	}
+	// the queue is not full, now the put above must succeed
+	goto retry
+}
+
+// Put g and a batch of work from local runnable queue on global queue.
+// Executed only by the owner P.
+func runqputslow(_p_ *p, gp *g, h, t uint32) bool {
+	var batch [len(_p_.runq)/2 + 1]*g
+
+	// First, grab a batch from local queue.
+	n := t - h
+	n = n / 2
+	if n != uint32(len(_p_.runq)/2) {
+		throw("runqputslow: queue is not full")
+	}
+	for i := uint32(0); i < n; i++ {
+		batch[i] = _p_.runq[(h+i)%uint32(len(_p_.runq))].ptr()
+	}
+	if !atomic.CasRel(&_p_.runqhead, h, h+n) { // cas-release, commits consume
+		return false
+	}
+	batch[n] = gp
+
+	if randomizeScheduler {
+		for i := uint32(1); i <= n; i++ {
+			j := fastrandn(i + 1)
+			batch[i], batch[j] = batch[j], batch[i]
+		}
+	}
+
+	// Link the goroutines.
+	for i := uint32(0); i < n; i++ {
+		batch[i].schedlink.set(batch[i+1])
+	}
+	var q gQueue
+	q.head.set(batch[0])
+	q.tail.set(batch[n])
+
+	// Now put the batch on global queue.
+	lock(&sched.lock)
+	globrunqputbatch(&q, int32(n+1))
+	unlock(&sched.lock)
+	return true
+}
+
+// runqputbatch tries to put all the G's on q on the local runnable queue.
+// If the queue is full, they are put on the global queue; in that case
+// this will temporarily acquire the scheduler lock.
+// Executed only by the owner P.
+func runqputbatch(pp *p, q *gQueue, qsize int) {
+	h := atomic.LoadAcq(&pp.runqhead)
+	t := pp.runqtail
+	n := uint32(0)
+	for !q.empty() && t-h < uint32(len(pp.runq)) {
+		gp := q.pop()
+		pp.runq[t%uint32(len(pp.runq))].set(gp)
+		t++
+		n++
+	}
+	qsize -= int(n)
+
+	if randomizeScheduler {
+		off := func(o uint32) uint32 {
+			return (pp.runqtail + o) % uint32(len(pp.runq))
+		}
+		for i := uint32(1); i < n; i++ {
+			j := fastrandn(i + 1)
+			pp.runq[off(i)], pp.runq[off(j)] = pp.runq[off(j)], pp.runq[off(i)]
+		}
+	}
+
+	atomic.StoreRel(&pp.runqtail, t)
+	if !q.empty() {
+		lock(&sched.lock)
+		globrunqputbatch(q, int32(qsize))
+		unlock(&sched.lock)
+	}
+}
+
+// Get g from local runnable queue.
+// If inheritTime is true, gp should inherit the remaining time in the
+// current time slice. Otherwise, it should start a new time slice.
+// Executed only by the owner P.
+func runqget(_p_ *p) (gp *g, inheritTime bool) {
+	// If there's a runnext, it's the next G to run.
+	next := _p_.runnext
+	// If the runnext is non-0 and the CAS fails, it could only have been stolen by another P,
+	// because other Ps can race to set runnext to 0, but only the current P can set it to non-0.
+	// Hence, there's no need to retry this CAS if it falls.
+	if next != 0 && _p_.runnext.cas(next, 0) {
+		return next.ptr(), true
+	}
+
+	for {
+		h := atomic.LoadAcq(&_p_.runqhead) // load-acquire, synchronize with other consumers
+		t := _p_.runqtail
+		if t == h {
+			return nil, false
+		}
+		gp := _p_.runq[h%uint32(len(_p_.runq))].ptr()
+		if atomic.CasRel(&_p_.runqhead, h, h+1) { // cas-release, commits consume
+			return gp, false
+		}
+	}
+}
+
+// runqdrain drains the local runnable queue of _p_ and returns all goroutines in it.
+// Executed only by the owner P.
+func runqdrain(_p_ *p) (drainQ gQueue, n uint32) {
+	oldNext := _p_.runnext
+	if oldNext != 0 && _p_.runnext.cas(oldNext, 0) {
+		drainQ.pushBack(oldNext.ptr())
+		n++
+	}
+
+retry:
+	h := atomic.LoadAcq(&_p_.runqhead) // load-acquire, synchronize with other consumers
+	t := _p_.runqtail
+	qn := t - h
+	if qn == 0 {
+		return
+	}
+	if qn > uint32(len(_p_.runq)) { // read inconsistent h and t
+		goto retry
+	}
+
+	if !atomic.CasRel(&_p_.runqhead, h, h+qn) { // cas-release, commits consume
+		goto retry
+	}
+
+	// We've inverted the order in which it gets G's from the local P's runnable queue
+	// and then advances the head pointer because we don't want to mess up the statuses of G's
+	// while runqdrain() and runqsteal() are running in parallel.
+	// Thus we should advance the head pointer before draining the local P into a gQueue,
+	// so that we can update any gp.schedlink only after we take the full ownership of G,
+	// meanwhile, other P's can't access to all G's in local P's runnable queue and steal them.
+	// See https://groups.google.com/g/golang-dev/c/0pTKxEKhHSc/m/6Q85QjdVBQAJ for more details.
+	for i := uint32(0); i < qn; i++ {
+		gp := _p_.runq[(h+i)%uint32(len(_p_.runq))].ptr()
+		drainQ.pushBack(gp)
+		n++
+	}
+	return
+}
+
+// Grabs a batch of goroutines from _p_'s runnable queue into batch.
+// Batch is a ring buffer starting at batchHead.
+// Returns number of grabbed goroutines.
+// Can be executed by any P.
+func runqgrab(_p_ *p, batch *[256]guintptr, batchHead uint32, stealRunNextG bool) uint32 {
+	for {
+		h := atomic.LoadAcq(&_p_.runqhead) // load-acquire, synchronize with other consumers
+		t := atomic.LoadAcq(&_p_.runqtail) // load-acquire, synchronize with the producer
+		n := t - h
+		n = n - n/2
+		if n == 0 {
+			if stealRunNextG {
+				// Try to steal from _p_.runnext.
+				if next := _p_.runnext; next != 0 {
+					if _p_.status == _Prunning {
+						// Sleep to ensure that _p_ isn't about to run the g
+						// we are about to steal.
+						// The important use case here is when the g running
+						// on _p_ ready()s another g and then almost
+						// immediately blocks. Instead of stealing runnext
+						// in this window, back off to give _p_ a chance to
+						// schedule runnext. This will avoid thrashing gs
+						// between different Ps.
+						// A sync chan send/recv takes ~50ns as of time of
+						// writing, so 3us gives ~50x overshoot.
+						if GOOS != "windows" && GOOS != "openbsd" && GOOS != "netbsd" {
+							usleep(3)
+						} else {
+							// On some platforms system timer granularity is
+							// 1-15ms, which is way too much for this
+							// optimization. So just yield.
+							osyield()
+						}
+					}
+					if !_p_.runnext.cas(next, 0) {
+						continue
+					}
+					batch[batchHead%uint32(len(batch))] = next
+					return 1
+				}
+			}
+			return 0
+		}
+		if n > uint32(len(_p_.runq)/2) { // read inconsistent h and t
+			continue
+		}
+		for i := uint32(0); i < n; i++ {
+			g := _p_.runq[(h+i)%uint32(len(_p_.runq))]
+			batch[(batchHead+i)%uint32(len(batch))] = g
+		}
+		if atomic.CasRel(&_p_.runqhead, h, h+n) { // cas-release, commits consume
+			return n
+		}
+	}
+}
+
+// Steal half of elements from local runnable queue of p2
+// and put onto local runnable queue of p.
+// Returns one of the stolen elements (or nil if failed).
+func runqsteal(_p_, p2 *p, stealRunNextG bool) *g {
+	t := _p_.runqtail
+	n := runqgrab(p2, &_p_.runq, t, stealRunNextG)
+	if n == 0 {
+		return nil
+	}
+	n--
+	gp := _p_.runq[(t+n)%uint32(len(_p_.runq))].ptr()
+	if n == 0 {
+		return gp
+	}
+	h := atomic.LoadAcq(&_p_.runqhead) // load-acquire, synchronize with consumers
+	if t-h+n >= uint32(len(_p_.runq)) {
+		throw("runqsteal: runq overflow")
+	}
+	atomic.StoreRel(&_p_.runqtail, t+n) // store-release, makes the item available for consumption
+	return gp
+}
+
+// A gQueue is a dequeue of Gs linked through g.schedlink. A G can only
+// be on one gQueue or gList at a time.
+type gQueue struct {
+	head guintptr
+	tail guintptr
+}
+
+// empty reports whether q is empty.
+func (q *gQueue) empty() bool {
+	return q.head == 0
+}
+
+// push adds gp to the head of q.
+func (q *gQueue) push(gp *g) {
+	gp.schedlink = q.head
+	q.head.set(gp)
+	if q.tail == 0 {
+		q.tail.set(gp)
+	}
+}
+
+// pushBack adds gp to the tail of q.
+func (q *gQueue) pushBack(gp *g) {
+	gp.schedlink = 0
+	if q.tail != 0 {
+		q.tail.ptr().schedlink.set(gp)
+	} else {
+		q.head.set(gp)
+	}
+	q.tail.set(gp)
+}
+
+// pushBackAll adds all Gs in q2 to the tail of q. After this q2 must
+// not be used.
+func (q *gQueue) pushBackAll(q2 gQueue) {
+	if q2.tail == 0 {
+		return
+	}
+	q2.tail.ptr().schedlink = 0
+	if q.tail != 0 {
+		q.tail.ptr().schedlink = q2.head
+	} else {
+		q.head = q2.head
+	}
+	q.tail = q2.tail
+}
+
+// pop removes and returns the head of queue q. It returns nil if
+// q is empty.
+func (q *gQueue) pop() *g {
+	gp := q.head.ptr()
+	if gp != nil {
+		q.head = gp.schedlink
+		if q.head == 0 {
+			q.tail = 0
+		}
+	}
+	return gp
+}
+
+// popList takes all Gs in q and returns them as a gList.
+func (q *gQueue) popList() gList {
+	stack := gList{q.head}
+	*q = gQueue{}
+	return stack
+}
+
+// A gList is a list of Gs linked through g.schedlink. A G can only be
+// on one gQueue or gList at a time.
+type gList struct {
+	head guintptr
+}
+
+// empty reports whether l is empty.
+func (l *gList) empty() bool {
+	return l.head == 0
+}
+
+// push adds gp to the head of l.
+func (l *gList) push(gp *g) {
+	gp.schedlink = l.head
+	l.head.set(gp)
+}
+
+// pushAll prepends all Gs in q to l.
+func (l *gList) pushAll(q gQueue) {
+	if !q.empty() {
+		q.tail.ptr().schedlink = l.head
+		l.head = q.head
+	}
+}
+
+// pop removes and returns the head of l. If l is empty, it returns nil.
+func (l *gList) pop() *g {
+	gp := l.head.ptr()
+	if gp != nil {
+		l.head = gp.schedlink
+	}
+	return gp
+}
+
+//go:linkname setMaxThreads runtime/debug.setMaxThreads
+func setMaxThreads(in int) (out int) {
+	lock(&sched.lock)
+	out = int(sched.maxmcount)
+	if in > 0x7fffffff { // MaxInt32
+		sched.maxmcount = 0x7fffffff
+	} else {
+		sched.maxmcount = int32(in)
+	}
+	checkmcount()
+	unlock(&sched.lock)
+	return
+}
+
+//go:nosplit
+func procPin() int {
+	_g_ := getg()
+	mp := _g_.m
+
+	mp.locks++
+	return int(mp.p.ptr().id)
+}
+
+//go:nosplit
+func procUnpin() {
+	_g_ := getg()
+	_g_.m.locks--
+}
+
+//go:linkname sync_runtime_procPin sync.runtime_procPin
+//go:nosplit
+func sync_runtime_procPin() int {
+	return procPin()
+}
+
+//go:linkname sync_runtime_procUnpin sync.runtime_procUnpin
+//go:nosplit
+func sync_runtime_procUnpin() {
+	procUnpin()
+}
+
+//go:linkname sync_atomic_runtime_procPin sync/atomic.runtime_procPin
+//go:nosplit
+func sync_atomic_runtime_procPin() int {
+	return procPin()
+}
+
+//go:linkname sync_atomic_runtime_procUnpin sync/atomic.runtime_procUnpin
+//go:nosplit
+func sync_atomic_runtime_procUnpin() {
+	procUnpin()
+}
+
+// Active spinning for sync.Mutex.
+//
+//go:linkname sync_runtime_canSpin sync.runtime_canSpin
+//go:nosplit
+func sync_runtime_canSpin(i int) bool {
+	// sync.Mutex is cooperative, so we are conservative with spinning.
+	// Spin only few times and only if running on a multicore machine and
+	// GOMAXPROCS>1 and there is at least one other running P and local runq is empty.
+	// As opposed to runtime mutex we don't do passive spinning here,
+	// because there can be work on global runq or on other Ps.
+	if i >= active_spin || ncpu <= 1 || gomaxprocs <= int32(sched.npidle+sched.nmspinning)+1 {
+		return false
+	}
+	if p := getg().m.p.ptr(); !runqempty(p) {
+		return false
+	}
+	return true
+}
+
+//go:linkname sync_runtime_doSpin sync.runtime_doSpin
+//go:nosplit
+func sync_runtime_doSpin() {
+	procyield(active_spin_cnt)
+}
+
+var stealOrder randomOrder
+
+// randomOrder/randomEnum are helper types for randomized work stealing.
+// They allow to enumerate all Ps in different pseudo-random orders without repetitions.
+// The algorithm is based on the fact that if we have X such that X and GOMAXPROCS
+// are coprime, then a sequences of (i + X) % GOMAXPROCS gives the required enumeration.
+type randomOrder struct {
+	count    uint32
+	coprimes []uint32
+}
+
+type randomEnum struct {
+	i     uint32
+	count uint32
+	pos   uint32
+	inc   uint32
+}
+
+func (ord *randomOrder) reset(count uint32) {
+	ord.count = count
+	ord.coprimes = ord.coprimes[:0]
+	for i := uint32(1); i <= count; i++ {
+		if gcd(i, count) == 1 {
+			ord.coprimes = append(ord.coprimes, i)
+		}
+	}
+}
+
+func (ord *randomOrder) start(i uint32) randomEnum {
+	return randomEnum{
+		count: ord.count,
+		pos:   i % ord.count,
+		inc:   ord.coprimes[i/ord.count%uint32(len(ord.coprimes))],
+	}
+}
+
+func (enum *randomEnum) done() bool {
+	return enum.i == enum.count
+}
+
+func (enum *randomEnum) next() {
+	enum.i++
+	enum.pos = (enum.pos + enum.inc) % enum.count
+}
+
+func (enum *randomEnum) position() uint32 {
+	return enum.pos
+}
+
+func gcd(a, b uint32) uint32 {
+	for b != 0 {
+		a, b = b, a%b
+	}
+	return a
+}
+
+// An initTask represents the set of initializations that need to be done for a package.
+// Keep in sync with ../../test/initempty.go:initTask
+type initTask struct {
+	// TODO: pack the first 3 fields more tightly?
+	state uintptr // 0 = uninitialized, 1 = in progress, 2 = done
+	ndeps uintptr
+	nfns  uintptr
+	// followed by ndeps instances of an *initTask, one per package depended on
+	// followed by nfns pcs, one per init function to run
+}
+
+// inittrace stores statistics for init functions which are
+// updated by malloc and newproc when active is true.
+var inittrace tracestat
+
+type tracestat struct {
+	active bool   // init tracing activation status
+	id     int64  // init goroutine id
+	allocs uint64 // heap allocations
+	bytes  uint64 // heap allocated bytes
+}
+
+func doInit(t *initTask) {
+	switch t.state {
+	case 2: // fully initialized
+		return
+	case 1: // initialization in progress
+		throw("recursive call during initialization - linker skew")
+	default: // not initialized yet
+		t.state = 1 // initialization in progress
+
+		for i := uintptr(0); i < t.ndeps; i++ {
+			p := add(unsafe.Pointer(t), (3+i)*goarch.PtrSize)
+			t2 := *(**initTask)(p)
+			doInit(t2)
+		}
+
+		if t.nfns == 0 {
+			t.state = 2 // initialization done
+			return
+		}
+
+		var (
+			start  int64
+			before tracestat
+		)
+
+		if inittrace.active {
+			start = nanotime()
+			// Load stats non-atomically since tracinit is updated only by this init goroutine.
+			before = inittrace
+		}
+
+		firstFunc := add(unsafe.Pointer(t), (3+t.ndeps)*goarch.PtrSize)
+		for i := uintptr(0); i < t.nfns; i++ {
+			p := add(firstFunc, i*goarch.PtrSize)
+			f := *(*func())(unsafe.Pointer(&p))
+			f()
+		}
+
+		if inittrace.active {
+			end := nanotime()
+			// Load stats non-atomically since tracinit is updated only by this init goroutine.
+			after := inittrace
+
+			f := *(*func())(unsafe.Pointer(&firstFunc))
+			pkg := funcpkgpath(findfunc(abi.FuncPCABIInternal(f)))
+
+			var sbuf [24]byte
+			print("init ", pkg, " @")
+			print(string(fmtNSAsMS(sbuf[:], uint64(start-runtimeInitTime))), " ms, ")
+			print(string(fmtNSAsMS(sbuf[:], uint64(end-start))), " ms clock, ")
+			print(string(itoa(sbuf[:], after.bytes-before.bytes)), " bytes, ")
+			print(string(itoa(sbuf[:], after.allocs-before.allocs)), " allocs")
+			print("\n")
+		}
+
+		t.state = 2 // initialization done
+	}
+}
diff --git a/contrib/go/_std_1.19/src/runtime/profbuf.go b/contrib/go/_std_1.19/src/runtime/profbuf.go
new file mode 100644
index 0000000000..3d907d5612
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/profbuf.go
@@ -0,0 +1,560 @@
+// Copyright 2017 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+// A profBuf is a lock-free buffer for profiling events,
+// safe for concurrent use by one reader and one writer.
+// The writer may be a signal handler running without a user g.
+// The reader is assumed to be a user g.
+//
+// Each logged event corresponds to a fixed size header, a list of
+// uintptrs (typically a stack), and exactly one unsafe.Pointer tag.
+// The header and uintptrs are stored in the circular buffer data and the
+// tag is stored in a circular buffer tags, running in parallel.
+// In the circular buffer data, each event takes 2+hdrsize+len(stk)
+// words: the value 2+hdrsize+len(stk), then the time of the event, then
+// hdrsize words giving the fixed-size header, and then len(stk) words
+// for the stack.
+//
+// The current effective offsets into the tags and data circular buffers
+// for reading and writing are stored in the high 30 and low 32 bits of r and w.
+// The bottom bits of the high 32 are additional flag bits in w, unused in r.
+// "Effective" offsets means the total number of reads or writes, mod 2^length.
+// The offset in the buffer is the effective offset mod the length of the buffer.
+// To make wraparound mod 2^length match wraparound mod length of the buffer,
+// the length of the buffer must be a power of two.
+//
+// If the reader catches up to the writer, a flag passed to read controls
+// whether the read blocks until more data is available. A read returns a
+// pointer to the buffer data itself; the caller is assumed to be done with
+// that data at the next read. The read offset rNext tracks the next offset to
+// be returned by read. By definition, r ≤ rNext ≤ w (before wraparound),
+// and rNext is only used by the reader, so it can be accessed without atomics.
+//
+// If the writer gets ahead of the reader, so that the buffer fills,
+// future writes are discarded and replaced in the output stream by an
+// overflow entry, which has size 2+hdrsize+1, time set to the time of
+// the first discarded write, a header of all zeroed words, and a "stack"
+// containing one word, the number of discarded writes.
+//
+// Between the time the buffer fills and the buffer becomes empty enough
+// to hold more data, the overflow entry is stored as a pending overflow
+// entry in the fields overflow and overflowTime. The pending overflow
+// entry can be turned into a real record by either the writer or the
+// reader. If the writer is called to write a new record and finds that
+// the output buffer has room for both the pending overflow entry and the
+// new record, the writer emits the pending overflow entry and the new
+// record into the buffer. If the reader is called to read data and finds
+// that the output buffer is empty but that there is a pending overflow
+// entry, the reader will return a synthesized record for the pending
+// overflow entry.
+//
+// Only the writer can create or add to a pending overflow entry, but
+// either the reader or the writer can clear the pending overflow entry.
+// A pending overflow entry is indicated by the low 32 bits of 'overflow'
+// holding the number of discarded writes, and overflowTime holding the
+// time of the first discarded write. The high 32 bits of 'overflow'
+// increment each time the low 32 bits transition from zero to non-zero
+// or vice versa. This sequence number avoids ABA problems in the use of
+// compare-and-swap to coordinate between reader and writer.
+// The overflowTime is only written when the low 32 bits of overflow are
+// zero, that is, only when there is no pending overflow entry, in
+// preparation for creating a new one. The reader can therefore fetch and
+// clear the entry atomically using
+//
+//	for {
+//		overflow = load(&b.overflow)
+//		if uint32(overflow) == 0 {
+//			// no pending entry
+//			break
+//		}
+//		time = load(&b.overflowTime)
+//		if cas(&b.overflow, overflow, ((overflow>>32)+1)<<32) {
+//			// pending entry cleared
+//			break
+//		}
+//	}
+//	if uint32(overflow) > 0 {
+//		emit entry for uint32(overflow), time
+//	}
+type profBuf struct {
+	// accessed atomically
+	r, w         profAtomic
+	overflow     uint64
+	overflowTime uint64
+	eof          uint32
+
+	// immutable (excluding slice content)
+	hdrsize uintptr
+	data    []uint64
+	tags    []unsafe.Pointer
+
+	// owned by reader
+	rNext       profIndex
+	overflowBuf []uint64 // for use by reader to return overflow record
+	wait        note
+}
+
+// A profAtomic is the atomically-accessed word holding a profIndex.
+type profAtomic uint64
+
+// A profIndex is the packet tag and data counts and flags bits, described above.
+type profIndex uint64
+
+const (
+	profReaderSleeping profIndex = 1 << 32 // reader is sleeping and must be woken up
+	profWriteExtra     profIndex = 1 << 33 // overflow or eof waiting
+)
+
+func (x *profAtomic) load() profIndex {
+	return profIndex(atomic.Load64((*uint64)(x)))
+}
+
+func (x *profAtomic) store(new profIndex) {
+	atomic.Store64((*uint64)(x), uint64(new))
+}
+
+func (x *profAtomic) cas(old, new profIndex) bool {
+	return atomic.Cas64((*uint64)(x), uint64(old), uint64(new))
+}
+
+func (x profIndex) dataCount() uint32 {
+	return uint32(x)
+}
+
+func (x profIndex) tagCount() uint32 {
+	return uint32(x >> 34)
+}
+
+// countSub subtracts two counts obtained from profIndex.dataCount or profIndex.tagCount,
+// assuming that they are no more than 2^29 apart (guaranteed since they are never more than
+// len(data) or len(tags) apart, respectively).
+// tagCount wraps at 2^30, while dataCount wraps at 2^32.
+// This function works for both.
+func countSub(x, y uint32) int {
+	// x-y is 32-bit signed or 30-bit signed; sign-extend to 32 bits and convert to int.
+	return int(int32(x-y) << 2 >> 2)
+}
+
+// addCountsAndClearFlags returns the packed form of "x + (data, tag) - all flags".
+func (x profIndex) addCountsAndClearFlags(data, tag int) profIndex {
+	return profIndex((uint64(x)>>34+uint64(uint32(tag)<<2>>2))<<34 | uint64(uint32(x)+uint32(data)))
+}
+
+// hasOverflow reports whether b has any overflow records pending.
+func (b *profBuf) hasOverflow() bool {
+	return uint32(atomic.Load64(&b.overflow)) > 0
+}
+
+// takeOverflow consumes the pending overflow records, returning the overflow count
+// and the time of the first overflow.
+// When called by the reader, it is racing against incrementOverflow.
+func (b *profBuf) takeOverflow() (count uint32, time uint64) {
+	overflow := atomic.Load64(&b.overflow)
+	time = atomic.Load64(&b.overflowTime)
+	for {
+		count = uint32(overflow)
+		if count == 0 {
+			time = 0
+			break
+		}
+		// Increment generation, clear overflow count in low bits.
+		if atomic.Cas64(&b.overflow, overflow, ((overflow>>32)+1)<<32) {
+			break
+		}
+		overflow = atomic.Load64(&b.overflow)
+		time = atomic.Load64(&b.overflowTime)
+	}
+	return uint32(overflow), time
+}
+
+// incrementOverflow records a single overflow at time now.
+// It is racing against a possible takeOverflow in the reader.
+func (b *profBuf) incrementOverflow(now int64) {
+	for {
+		overflow := atomic.Load64(&b.overflow)
+
+		// Once we see b.overflow reach 0, it's stable: no one else is changing it underfoot.
+		// We need to set overflowTime if we're incrementing b.overflow from 0.
+		if uint32(overflow) == 0 {
+			// Store overflowTime first so it's always available when overflow != 0.
+			atomic.Store64(&b.overflowTime, uint64(now))
+			atomic.Store64(&b.overflow, (((overflow>>32)+1)<<32)+1)
+			break
+		}
+		// Otherwise we're racing to increment against reader
+		// who wants to set b.overflow to 0.
+		// Out of paranoia, leave 2³²-1 a sticky overflow value,
+		// to avoid wrapping around. Extremely unlikely.
+		if int32(overflow) == -1 {
+			break
+		}
+		if atomic.Cas64(&b.overflow, overflow, overflow+1) {
+			break
+		}
+	}
+}
+
+// newProfBuf returns a new profiling buffer with room for
+// a header of hdrsize words and a buffer of at least bufwords words.
+func newProfBuf(hdrsize, bufwords, tags int) *profBuf {
+	if min := 2 + hdrsize + 1; bufwords < min {
+		bufwords = min
+	}
+
+	// Buffer sizes must be power of two, so that we don't have to
+	// worry about uint32 wraparound changing the effective position
+	// within the buffers. We store 30 bits of count; limiting to 28
+	// gives us some room for intermediate calculations.
+	if bufwords >= 1<<28 || tags >= 1<<28 {
+		throw("newProfBuf: buffer too large")
+	}
+	var i int
+	for i = 1; i < bufwords; i <<= 1 {
+	}
+	bufwords = i
+	for i = 1; i < tags; i <<= 1 {
+	}
+	tags = i
+
+	b := new(profBuf)
+	b.hdrsize = uintptr(hdrsize)
+	b.data = make([]uint64, bufwords)
+	b.tags = make([]unsafe.Pointer, tags)
+	b.overflowBuf = make([]uint64, 2+b.hdrsize+1)
+	return b
+}
+
+// canWriteRecord reports whether the buffer has room
+// for a single contiguous record with a stack of length nstk.
+func (b *profBuf) canWriteRecord(nstk int) bool {
+	br := b.r.load()
+	bw := b.w.load()
+
+	// room for tag?
+	if countSub(br.tagCount(), bw.tagCount())+len(b.tags) < 1 {
+		return false
+	}
+
+	// room for data?
+	nd := countSub(br.dataCount(), bw.dataCount()) + len(b.data)
+	want := 2 + int(b.hdrsize) + nstk
+	i := int(bw.dataCount() % uint32(len(b.data)))
+	if i+want > len(b.data) {
+		// Can't fit in trailing fragment of slice.
+		// Skip over that and start over at beginning of slice.
+		nd -= len(b.data) - i
+	}
+	return nd >= want
+}
+
+// canWriteTwoRecords reports whether the buffer has room
+// for two records with stack lengths nstk1, nstk2, in that order.
+// Each record must be contiguous on its own, but the two
+// records need not be contiguous (one can be at the end of the buffer
+// and the other can wrap around and start at the beginning of the buffer).
+func (b *profBuf) canWriteTwoRecords(nstk1, nstk2 int) bool {
+	br := b.r.load()
+	bw := b.w.load()
+
+	// room for tag?
+	if countSub(br.tagCount(), bw.tagCount())+len(b.tags) < 2 {
+		return false
+	}
+
+	// room for data?
+	nd := countSub(br.dataCount(), bw.dataCount()) + len(b.data)
+
+	// first record
+	want := 2 + int(b.hdrsize) + nstk1
+	i := int(bw.dataCount() % uint32(len(b.data)))
+	if i+want > len(b.data) {
+		// Can't fit in trailing fragment of slice.
+		// Skip over that and start over at beginning of slice.
+		nd -= len(b.data) - i
+		i = 0
+	}
+	i += want
+	nd -= want
+
+	// second record
+	want = 2 + int(b.hdrsize) + nstk2
+	if i+want > len(b.data) {
+		// Can't fit in trailing fragment of slice.
+		// Skip over that and start over at beginning of slice.
+		nd -= len(b.data) - i
+		i = 0
+	}
+	return nd >= want
+}
+
+// write writes an entry to the profiling buffer b.
+// The entry begins with a fixed hdr, which must have
+// length b.hdrsize, followed by a variable-sized stack
+// and a single tag pointer *tagPtr (or nil if tagPtr is nil).
+// No write barriers allowed because this might be called from a signal handler.
+func (b *profBuf) write(tagPtr *unsafe.Pointer, now int64, hdr []uint64, stk []uintptr) {
+	if b == nil {
+		return
+	}
+	if len(hdr) > int(b.hdrsize) {
+		throw("misuse of profBuf.write")
+	}
+
+	if hasOverflow := b.hasOverflow(); hasOverflow && b.canWriteTwoRecords(1, len(stk)) {
+		// Room for both an overflow record and the one being written.
+		// Write the overflow record if the reader hasn't gotten to it yet.
+		// Only racing against reader, not other writers.
+		count, time := b.takeOverflow()
+		if count > 0 {
+			var stk [1]uintptr
+			stk[0] = uintptr(count)
+			b.write(nil, int64(time), nil, stk[:])
+		}
+	} else if hasOverflow || !b.canWriteRecord(len(stk)) {
+		// Pending overflow without room to write overflow and new records
+		// or no overflow but also no room for new record.
+		b.incrementOverflow(now)
+		b.wakeupExtra()
+		return
+	}
+
+	// There's room: write the record.
+	br := b.r.load()
+	bw := b.w.load()
+
+	// Profiling tag
+	//
+	// The tag is a pointer, but we can't run a write barrier here.
+	// We have interrupted the OS-level execution of gp, but the
+	// runtime still sees gp as executing. In effect, we are running
+	// in place of the real gp. Since gp is the only goroutine that
+	// can overwrite gp.labels, the value of gp.labels is stable during
+	// this signal handler: it will still be reachable from gp when
+	// we finish executing. If a GC is in progress right now, it must
+	// keep gp.labels alive, because gp.labels is reachable from gp.
+	// If gp were to overwrite gp.labels, the deletion barrier would
+	// still shade that pointer, which would preserve it for the
+	// in-progress GC, so all is well. Any future GC will see the
+	// value we copied when scanning b.tags (heap-allocated).
+	// We arrange that the store here is always overwriting a nil,
+	// so there is no need for a deletion barrier on b.tags[wt].
+	wt := int(bw.tagCount() % uint32(len(b.tags)))
+	if tagPtr != nil {
+		*(*uintptr)(unsafe.Pointer(&b.tags[wt])) = uintptr(unsafe.Pointer(*tagPtr))
+	}
+
+	// Main record.
+	// It has to fit in a contiguous section of the slice, so if it doesn't fit at the end,
+	// leave a rewind marker (0) and start over at the beginning of the slice.
+	wd := int(bw.dataCount() % uint32(len(b.data)))
+	nd := countSub(br.dataCount(), bw.dataCount()) + len(b.data)
+	skip := 0
+	if wd+2+int(b.hdrsize)+len(stk) > len(b.data) {
+		b.data[wd] = 0
+		skip = len(b.data) - wd
+		nd -= skip
+		wd = 0
+	}
+	data := b.data[wd:]
+	data[0] = uint64(2 + b.hdrsize + uintptr(len(stk))) // length
+	data[1] = uint64(now)                               // time stamp
+	// header, zero-padded
+	i := uintptr(copy(data[2:2+b.hdrsize], hdr))
+	for ; i < b.hdrsize; i++ {
+		data[2+i] = 0
+	}
+	for i, pc := range stk {
+		data[2+b.hdrsize+uintptr(i)] = uint64(pc)
+	}
+
+	for {
+		// Commit write.
+		// Racing with reader setting flag bits in b.w, to avoid lost wakeups.
+		old := b.w.load()
+		new := old.addCountsAndClearFlags(skip+2+len(stk)+int(b.hdrsize), 1)
+		if !b.w.cas(old, new) {
+			continue
+		}
+		// If there was a reader, wake it up.
+		if old&profReaderSleeping != 0 {
+			notewakeup(&b.wait)
+		}
+		break
+	}
+}
+
+// close signals that there will be no more writes on the buffer.
+// Once all the data has been read from the buffer, reads will return eof=true.
+func (b *profBuf) close() {
+	if atomic.Load(&b.eof) > 0 {
+		throw("runtime: profBuf already closed")
+	}
+	atomic.Store(&b.eof, 1)
+	b.wakeupExtra()
+}
+
+// wakeupExtra must be called after setting one of the "extra"
+// atomic fields b.overflow or b.eof.
+// It records the change in b.w and wakes up the reader if needed.
+func (b *profBuf) wakeupExtra() {
+	for {
+		old := b.w.load()
+		new := old | profWriteExtra
+		if !b.w.cas(old, new) {
+			continue
+		}
+		if old&profReaderSleeping != 0 {
+			notewakeup(&b.wait)
+		}
+		break
+	}
+}
+
+// profBufReadMode specifies whether to block when no data is available to read.
+type profBufReadMode int
+
+const (
+	profBufBlocking profBufReadMode = iota
+	profBufNonBlocking
+)
+
+var overflowTag [1]unsafe.Pointer // always nil
+
+func (b *profBuf) read(mode profBufReadMode) (data []uint64, tags []unsafe.Pointer, eof bool) {
+	if b == nil {
+		return nil, nil, true
+	}
+
+	br := b.rNext
+
+	// Commit previous read, returning that part of the ring to the writer.
+	// First clear tags that have now been read, both to avoid holding
+	// up the memory they point at for longer than necessary
+	// and so that b.write can assume it is always overwriting
+	// nil tag entries (see comment in b.write).
+	rPrev := b.r.load()
+	if rPrev != br {
+		ntag := countSub(br.tagCount(), rPrev.tagCount())
+		ti := int(rPrev.tagCount() % uint32(len(b.tags)))
+		for i := 0; i < ntag; i++ {
+			b.tags[ti] = nil
+			if ti++; ti == len(b.tags) {
+				ti = 0
+			}
+		}
+		b.r.store(br)
+	}
+
+Read:
+	bw := b.w.load()
+	numData := countSub(bw.dataCount(), br.dataCount())
+	if numData == 0 {
+		if b.hasOverflow() {
+			// No data to read, but there is overflow to report.
+			// Racing with writer flushing b.overflow into a real record.
+			count, time := b.takeOverflow()
+			if count == 0 {
+				// Lost the race, go around again.
+				goto Read
+			}
+			// Won the race, report overflow.
+			dst := b.overflowBuf
+			dst[0] = uint64(2 + b.hdrsize + 1)
+			dst[1] = uint64(time)
+			for i := uintptr(0); i < b.hdrsize; i++ {
+				dst[2+i] = 0
+			}
+			dst[2+b.hdrsize] = uint64(count)
+			return dst[:2+b.hdrsize+1], overflowTag[:1], false
+		}
+		if atomic.Load(&b.eof) > 0 {
+			// No data, no overflow, EOF set: done.
+			return nil, nil, true
+		}
+		if bw&profWriteExtra != 0 {
+			// Writer claims to have published extra information (overflow or eof).
+			// Attempt to clear notification and then check again.
+			// If we fail to clear the notification it means b.w changed,
+			// so we still need to check again.
+			b.w.cas(bw, bw&^profWriteExtra)
+			goto Read
+		}
+
+		// Nothing to read right now.
+		// Return or sleep according to mode.
+		if mode == profBufNonBlocking {
+			return nil, nil, false
+		}
+		if !b.w.cas(bw, bw|profReaderSleeping) {
+			goto Read
+		}
+		// Committed to sleeping.
+		notetsleepg(&b.wait, -1)
+		noteclear(&b.wait)
+		goto Read
+	}
+	data = b.data[br.dataCount()%uint32(len(b.data)):]
+	if len(data) > numData {
+		data = data[:numData]
+	} else {
+		numData -= len(data) // available in case of wraparound
+	}
+	skip := 0
+	if data[0] == 0 {
+		// Wraparound record. Go back to the beginning of the ring.
+		skip = len(data)
+		data = b.data
+		if len(data) > numData {
+			data = data[:numData]
+		}
+	}
+
+	ntag := countSub(bw.tagCount(), br.tagCount())
+	if ntag == 0 {
+		throw("runtime: malformed profBuf buffer - tag and data out of sync")
+	}
+	tags = b.tags[br.tagCount()%uint32(len(b.tags)):]
+	if len(tags) > ntag {
+		tags = tags[:ntag]
+	}
+
+	// Count out whole data records until either data or tags is done.
+	// They are always in sync in the buffer, but due to an end-of-slice
+	// wraparound we might need to stop early and return the rest
+	// in the next call.
+	di := 0
+	ti := 0
+	for di < len(data) && data[di] != 0 && ti < len(tags) {
+		if uintptr(di)+uintptr(data[di]) > uintptr(len(data)) {
+			throw("runtime: malformed profBuf buffer - invalid size")
+		}
+		di += int(data[di])
+		ti++
+	}
+
+	// Remember how much we returned, to commit read on next call.
+	b.rNext = br.addCountsAndClearFlags(skip+di, ti)
+
+	if raceenabled {
+		// Match racereleasemerge in runtime_setProfLabel,
+		// so that the setting of the labels in runtime_setProfLabel
+		// is treated as happening before any use of the labels
+		// by our caller. The synchronization on labelSync itself is a fiction
+		// for the race detector. The actual synchronization is handled
+		// by the fact that the signal handler only reads from the current
+		// goroutine and uses atomics to write the updated queue indices,
+		// and then the read-out from the signal handler buffer uses
+		// atomics to read those queue indices.
+		raceacquire(unsafe.Pointer(&labelSync))
+	}
+
+	return data[:di], tags[:ti], false
+}
diff --git a/contrib/go/_std_1.18/src/runtime/proflabel.go b/contrib/go/_std_1.19/src/runtime/proflabel.go
index b2a161729e..b2a161729e 100644
--- a/contrib/go/_std_1.18/src/runtime/proflabel.go
+++ b/contrib/go/_std_1.19/src/runtime/proflabel.go
diff --git a/contrib/go/_std_1.18/src/runtime/race0.go b/contrib/go/_std_1.19/src/runtime/race0.go
index f36d4387c7..f36d4387c7 100644
--- a/contrib/go/_std_1.18/src/runtime/race0.go
+++ b/contrib/go/_std_1.19/src/runtime/race0.go
diff --git a/contrib/go/_std_1.18/src/runtime/rdebug.go b/contrib/go/_std_1.19/src/runtime/rdebug.go
index 1b213f1934..1b213f1934 100644
--- a/contrib/go/_std_1.18/src/runtime/rdebug.go
+++ b/contrib/go/_std_1.19/src/runtime/rdebug.go
diff --git a/contrib/go/_std_1.18/src/runtime/relax_stub.go b/contrib/go/_std_1.19/src/runtime/relax_stub.go
index e507702fc1..e507702fc1 100644
--- a/contrib/go/_std_1.18/src/runtime/relax_stub.go
+++ b/contrib/go/_std_1.19/src/runtime/relax_stub.go
diff --git a/contrib/go/_std_1.18/src/runtime/rt0_darwin_amd64.s b/contrib/go/_std_1.19/src/runtime/rt0_darwin_amd64.s
index ed804d47c5..ed804d47c5 100644
--- a/contrib/go/_std_1.18/src/runtime/rt0_darwin_amd64.s
+++ b/contrib/go/_std_1.19/src/runtime/rt0_darwin_amd64.s
diff --git a/contrib/go/_std_1.18/src/runtime/rt0_linux_amd64.s b/contrib/go/_std_1.19/src/runtime/rt0_linux_amd64.s
index 94ff7094d6..94ff7094d6 100644
--- a/contrib/go/_std_1.18/src/runtime/rt0_linux_amd64.s
+++ b/contrib/go/_std_1.19/src/runtime/rt0_linux_amd64.s
diff --git a/contrib/go/_std_1.19/src/runtime/runtime.go b/contrib/go/_std_1.19/src/runtime/runtime.go
new file mode 100644
index 0000000000..2cf93abefa
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/runtime.go
@@ -0,0 +1,67 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"runtime/internal/atomic"
+	_ "unsafe" // for go:linkname
+)
+
+//go:generate go run wincallback.go
+//go:generate go run mkduff.go
+//go:generate go run mkfastlog2table.go
+
+var ticks ticksType
+
+type ticksType struct {
+	lock mutex
+	pad  uint32 // ensure 8-byte alignment of val on 386
+	val  uint64
+}
+
+// Note: Called by runtime/pprof in addition to runtime code.
+func tickspersecond() int64 {
+	r := int64(atomic.Load64(&ticks.val))
+	if r != 0 {
+		return r
+	}
+	lock(&ticks.lock)
+	r = int64(ticks.val)
+	if r == 0 {
+		t0 := nanotime()
+		c0 := cputicks()
+		usleep(100 * 1000)
+		t1 := nanotime()
+		c1 := cputicks()
+		if t1 == t0 {
+			t1++
+		}
+		r = (c1 - c0) * 1000 * 1000 * 1000 / (t1 - t0)
+		if r == 0 {
+			r++
+		}
+		atomic.Store64(&ticks.val, uint64(r))
+	}
+	unlock(&ticks.lock)
+	return r
+}
+
+var envs []string
+var argslice []string
+
+//go:linkname syscall_runtime_envs syscall.runtime_envs
+func syscall_runtime_envs() []string { return append([]string{}, envs...) }
+
+//go:linkname syscall_Getpagesize syscall.Getpagesize
+func syscall_Getpagesize() int { return int(physPageSize) }
+
+//go:linkname os_runtime_args os.runtime_args
+func os_runtime_args() []string { return append([]string{}, argslice...) }
+
+//go:linkname syscall_Exit syscall.Exit
+//go:nosplit
+func syscall_Exit(code int) {
+	exit(int32(code))
+}
diff --git a/contrib/go/_std_1.19/src/runtime/runtime1.go b/contrib/go/_std_1.19/src/runtime/runtime1.go
new file mode 100644
index 0000000000..e307901fc2
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/runtime1.go
@@ -0,0 +1,559 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"internal/bytealg"
+	"internal/goarch"
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+// Keep a cached value to make gotraceback fast,
+// since we call it on every call to gentraceback.
+// The cached value is a uint32 in which the low bits
+// are the "crash" and "all" settings and the remaining
+// bits are the traceback value (0 off, 1 on, 2 include system).
+const (
+	tracebackCrash = 1 << iota
+	tracebackAll
+	tracebackShift = iota
+)
+
+var traceback_cache uint32 = 2 << tracebackShift
+var traceback_env uint32
+
+// gotraceback returns the current traceback settings.
+//
+// If level is 0, suppress all tracebacks.
+// If level is 1, show tracebacks, but exclude runtime frames.
+// If level is 2, show tracebacks including runtime frames.
+// If all is set, print all goroutine stacks. Otherwise, print just the current goroutine.
+// If crash is set, crash (core dump, etc) after tracebacking.
+//
+//go:nosplit
+func gotraceback() (level int32, all, crash bool) {
+	_g_ := getg()
+	t := atomic.Load(&traceback_cache)
+	crash = t&tracebackCrash != 0
+	all = _g_.m.throwing >= throwTypeUser || t&tracebackAll != 0
+	if _g_.m.traceback != 0 {
+		level = int32(_g_.m.traceback)
+	} else if _g_.m.throwing >= throwTypeRuntime {
+		// Always include runtime frames in runtime throws unless
+		// otherwise overridden by m.traceback.
+		level = 2
+	} else {
+		level = int32(t >> tracebackShift)
+	}
+	return
+}
+
+var (
+	argc int32
+	argv **byte
+)
+
+// nosplit for use in linux startup sysargs
+//
+//go:nosplit
+func argv_index(argv **byte, i int32) *byte {
+	return *(**byte)(add(unsafe.Pointer(argv), uintptr(i)*goarch.PtrSize))
+}
+
+func args(c int32, v **byte) {
+	argc = c
+	argv = v
+	sysargs(c, v)
+}
+
+func goargs() {
+	if GOOS == "windows" {
+		return
+	}
+	argslice = make([]string, argc)
+	for i := int32(0); i < argc; i++ {
+		argslice[i] = gostringnocopy(argv_index(argv, i))
+	}
+}
+
+func goenvs_unix() {
+	// TODO(austin): ppc64 in dynamic linking mode doesn't
+	// guarantee env[] will immediately follow argv. Might cause
+	// problems.
+	n := int32(0)
+	for argv_index(argv, argc+1+n) != nil {
+		n++
+	}
+
+	envs = make([]string, n)
+	for i := int32(0); i < n; i++ {
+		envs[i] = gostring(argv_index(argv, argc+1+i))
+	}
+}
+
+func environ() []string {
+	return envs
+}
+
+// TODO: These should be locals in testAtomic64, but we don't 8-byte
+// align stack variables on 386.
+var test_z64, test_x64 uint64
+
+func testAtomic64() {
+	test_z64 = 42
+	test_x64 = 0
+	if atomic.Cas64(&test_z64, test_x64, 1) {
+		throw("cas64 failed")
+	}
+	if test_x64 != 0 {
+		throw("cas64 failed")
+	}
+	test_x64 = 42
+	if !atomic.Cas64(&test_z64, test_x64, 1) {
+		throw("cas64 failed")
+	}
+	if test_x64 != 42 || test_z64 != 1 {
+		throw("cas64 failed")
+	}
+	if atomic.Load64(&test_z64) != 1 {
+		throw("load64 failed")
+	}
+	atomic.Store64(&test_z64, (1<<40)+1)
+	if atomic.Load64(&test_z64) != (1<<40)+1 {
+		throw("store64 failed")
+	}
+	if atomic.Xadd64(&test_z64, (1<<40)+1) != (2<<40)+2 {
+		throw("xadd64 failed")
+	}
+	if atomic.Load64(&test_z64) != (2<<40)+2 {
+		throw("xadd64 failed")
+	}
+	if atomic.Xchg64(&test_z64, (3<<40)+3) != (2<<40)+2 {
+		throw("xchg64 failed")
+	}
+	if atomic.Load64(&test_z64) != (3<<40)+3 {
+		throw("xchg64 failed")
+	}
+}
+
+func check() {
+	var (
+		a     int8
+		b     uint8
+		c     int16
+		d     uint16
+		e     int32
+		f     uint32
+		g     int64
+		h     uint64
+		i, i1 float32
+		j, j1 float64
+		k     unsafe.Pointer
+		l     *uint16
+		m     [4]byte
+	)
+	type x1t struct {
+		x uint8
+	}
+	type y1t struct {
+		x1 x1t
+		y  uint8
+	}
+	var x1 x1t
+	var y1 y1t
+
+	if unsafe.Sizeof(a) != 1 {
+		throw("bad a")
+	}
+	if unsafe.Sizeof(b) != 1 {
+		throw("bad b")
+	}
+	if unsafe.Sizeof(c) != 2 {
+		throw("bad c")
+	}
+	if unsafe.Sizeof(d) != 2 {
+		throw("bad d")
+	}
+	if unsafe.Sizeof(e) != 4 {
+		throw("bad e")
+	}
+	if unsafe.Sizeof(f) != 4 {
+		throw("bad f")
+	}
+	if unsafe.Sizeof(g) != 8 {
+		throw("bad g")
+	}
+	if unsafe.Sizeof(h) != 8 {
+		throw("bad h")
+	}
+	if unsafe.Sizeof(i) != 4 {
+		throw("bad i")
+	}
+	if unsafe.Sizeof(j) != 8 {
+		throw("bad j")
+	}
+	if unsafe.Sizeof(k) != goarch.PtrSize {
+		throw("bad k")
+	}
+	if unsafe.Sizeof(l) != goarch.PtrSize {
+		throw("bad l")
+	}
+	if unsafe.Sizeof(x1) != 1 {
+		throw("bad unsafe.Sizeof x1")
+	}
+	if unsafe.Offsetof(y1.y) != 1 {
+		throw("bad offsetof y1.y")
+	}
+	if unsafe.Sizeof(y1) != 2 {
+		throw("bad unsafe.Sizeof y1")
+	}
+
+	if timediv(12345*1000000000+54321, 1000000000, &e) != 12345 || e != 54321 {
+		throw("bad timediv")
+	}
+
+	var z uint32
+	z = 1
+	if !atomic.Cas(&z, 1, 2) {
+		throw("cas1")
+	}
+	if z != 2 {
+		throw("cas2")
+	}
+
+	z = 4
+	if atomic.Cas(&z, 5, 6) {
+		throw("cas3")
+	}
+	if z != 4 {
+		throw("cas4")
+	}
+
+	z = 0xffffffff
+	if !atomic.Cas(&z, 0xffffffff, 0xfffffffe) {
+		throw("cas5")
+	}
+	if z != 0xfffffffe {
+		throw("cas6")
+	}
+
+	m = [4]byte{1, 1, 1, 1}
+	atomic.Or8(&m[1], 0xf0)
+	if m[0] != 1 || m[1] != 0xf1 || m[2] != 1 || m[3] != 1 {
+		throw("atomicor8")
+	}
+
+	m = [4]byte{0xff, 0xff, 0xff, 0xff}
+	atomic.And8(&m[1], 0x1)
+	if m[0] != 0xff || m[1] != 0x1 || m[2] != 0xff || m[3] != 0xff {
+		throw("atomicand8")
+	}
+
+	*(*uint64)(unsafe.Pointer(&j)) = ^uint64(0)
+	if j == j {
+		throw("float64nan")
+	}
+	if !(j != j) {
+		throw("float64nan1")
+	}
+
+	*(*uint64)(unsafe.Pointer(&j1)) = ^uint64(1)
+	if j == j1 {
+		throw("float64nan2")
+	}
+	if !(j != j1) {
+		throw("float64nan3")
+	}
+
+	*(*uint32)(unsafe.Pointer(&i)) = ^uint32(0)
+	if i == i {
+		throw("float32nan")
+	}
+	if i == i {
+		throw("float32nan1")
+	}
+
+	*(*uint32)(unsafe.Pointer(&i1)) = ^uint32(1)
+	if i == i1 {
+		throw("float32nan2")
+	}
+	if i == i1 {
+		throw("float32nan3")
+	}
+
+	testAtomic64()
+
+	if _FixedStack != round2(_FixedStack) {
+		throw("FixedStack is not power-of-2")
+	}
+
+	if !checkASM() {
+		throw("assembly checks failed")
+	}
+}
+
+type dbgVar struct {
+	name  string
+	value *int32
+}
+
+// Holds variables parsed from GODEBUG env var,
+// except for "memprofilerate" since there is an
+// existing int var for that value, which may
+// already have an initial value.
+var debug struct {
+	cgocheck           int32
+	clobberfree        int32
+	efence             int32
+	gccheckmark        int32
+	gcpacertrace       int32
+	gcshrinkstackoff   int32
+	gcstoptheworld     int32
+	gctrace            int32
+	invalidptr         int32
+	madvdontneed       int32 // for Linux; issue 28466
+	scavtrace          int32
+	scheddetail        int32
+	schedtrace         int32
+	tracebackancestors int32
+	asyncpreemptoff    int32
+	harddecommit       int32
+	adaptivestackstart int32
+
+	// debug.malloc is used as a combined debug check
+	// in the malloc function and should be set
+	// if any of the below debug options is != 0.
+	malloc         bool
+	allocfreetrace int32
+	inittrace      int32
+	sbrk           int32
+}
+
+var dbgvars = []dbgVar{
+	{"allocfreetrace", &debug.allocfreetrace},
+	{"clobberfree", &debug.clobberfree},
+	{"cgocheck", &debug.cgocheck},
+	{"efence", &debug.efence},
+	{"gccheckmark", &debug.gccheckmark},
+	{"gcpacertrace", &debug.gcpacertrace},
+	{"gcshrinkstackoff", &debug.gcshrinkstackoff},
+	{"gcstoptheworld", &debug.gcstoptheworld},
+	{"gctrace", &debug.gctrace},
+	{"invalidptr", &debug.invalidptr},
+	{"madvdontneed", &debug.madvdontneed},
+	{"sbrk", &debug.sbrk},
+	{"scavtrace", &debug.scavtrace},
+	{"scheddetail", &debug.scheddetail},
+	{"schedtrace", &debug.schedtrace},
+	{"tracebackancestors", &debug.tracebackancestors},
+	{"asyncpreemptoff", &debug.asyncpreemptoff},
+	{"inittrace", &debug.inittrace},
+	{"harddecommit", &debug.harddecommit},
+	{"adaptivestackstart", &debug.adaptivestackstart},
+}
+
+func parsedebugvars() {
+	// defaults
+	debug.cgocheck = 1
+	debug.invalidptr = 1
+	debug.adaptivestackstart = 1 // go119 - set this to 0 to turn larger initial goroutine stacks off
+	if GOOS == "linux" {
+		// On Linux, MADV_FREE is faster than MADV_DONTNEED,
+		// but doesn't affect many of the statistics that
+		// MADV_DONTNEED does until the memory is actually
+		// reclaimed. This generally leads to poor user
+		// experience, like confusing stats in top and other
+		// monitoring tools; and bad integration with
+		// management systems that respond to memory usage.
+		// Hence, default to MADV_DONTNEED.
+		debug.madvdontneed = 1
+	}
+
+	for p := gogetenv("GODEBUG"); p != ""; {
+		field := ""
+		i := bytealg.IndexByteString(p, ',')
+		if i < 0 {
+			field, p = p, ""
+		} else {
+			field, p = p[:i], p[i+1:]
+		}
+		i = bytealg.IndexByteString(field, '=')
+		if i < 0 {
+			continue
+		}
+		key, value := field[:i], field[i+1:]
+
+		// Update MemProfileRate directly here since it
+		// is int, not int32, and should only be updated
+		// if specified in GODEBUG.
+		if key == "memprofilerate" {
+			if n, ok := atoi(value); ok {
+				MemProfileRate = n
+			}
+		} else {
+			for _, v := range dbgvars {
+				if v.name == key {
+					if n, ok := atoi32(value); ok {
+						*v.value = n
+					}
+				}
+			}
+		}
+	}
+
+	debug.malloc = (debug.allocfreetrace | debug.inittrace | debug.sbrk) != 0
+
+	setTraceback(gogetenv("GOTRACEBACK"))
+	traceback_env = traceback_cache
+}
+
+//go:linkname setTraceback runtime/debug.SetTraceback
+func setTraceback(level string) {
+	var t uint32
+	switch level {
+	case "none":
+		t = 0
+	case "single", "":
+		t = 1 << tracebackShift
+	case "all":
+		t = 1<<tracebackShift | tracebackAll
+	case "system":
+		t = 2<<tracebackShift | tracebackAll
+	case "crash":
+		t = 2<<tracebackShift | tracebackAll | tracebackCrash
+	default:
+		t = tracebackAll
+		if n, ok := atoi(level); ok && n == int(uint32(n)) {
+			t |= uint32(n) << tracebackShift
+		}
+	}
+	// when C owns the process, simply exit'ing the process on fatal errors
+	// and panics is surprising. Be louder and abort instead.
+	if islibrary || isarchive {
+		t |= tracebackCrash
+	}
+
+	t |= traceback_env
+
+	atomic.Store(&traceback_cache, t)
+}
+
+// Poor mans 64-bit division.
+// This is a very special function, do not use it if you are not sure what you are doing.
+// int64 division is lowered into _divv() call on 386, which does not fit into nosplit functions.
+// Handles overflow in a time-specific manner.
+// This keeps us within no-split stack limits on 32-bit processors.
+//
+//go:nosplit
+func timediv(v int64, div int32, rem *int32) int32 {
+	res := int32(0)
+	for bit := 30; bit >= 0; bit-- {
+		if v >= int64(div)<<uint(bit) {
+			v = v - (int64(div) << uint(bit))
+			// Before this for loop, res was 0, thus all these
+			// power of 2 increments are now just bitsets.
+			res |= 1 << uint(bit)
+		}
+	}
+	if v >= int64(div) {
+		if rem != nil {
+			*rem = 0
+		}
+		return 0x7fffffff
+	}
+	if rem != nil {
+		*rem = int32(v)
+	}
+	return res
+}
+
+// Helpers for Go. Must be NOSPLIT, must only call NOSPLIT functions, and must not block.
+
+//go:nosplit
+func acquirem() *m {
+	_g_ := getg()
+	_g_.m.locks++
+	return _g_.m
+}
+
+//go:nosplit
+func releasem(mp *m) {
+	_g_ := getg()
+	mp.locks--
+	if mp.locks == 0 && _g_.preempt {
+		// restore the preemption request in case we've cleared it in newstack
+		_g_.stackguard0 = stackPreempt
+	}
+}
+
+//go:linkname reflect_typelinks reflect.typelinks
+func reflect_typelinks() ([]unsafe.Pointer, [][]int32) {
+	modules := activeModules()
+	sections := []unsafe.Pointer{unsafe.Pointer(modules[0].types)}
+	ret := [][]int32{modules[0].typelinks}
+	for _, md := range modules[1:] {
+		sections = append(sections, unsafe.Pointer(md.types))
+		ret = append(ret, md.typelinks)
+	}
+	return sections, ret
+}
+
+// reflect_resolveNameOff resolves a name offset from a base pointer.
+//
+//go:linkname reflect_resolveNameOff reflect.resolveNameOff
+func reflect_resolveNameOff(ptrInModule unsafe.Pointer, off int32) unsafe.Pointer {
+	return unsafe.Pointer(resolveNameOff(ptrInModule, nameOff(off)).bytes)
+}
+
+// reflect_resolveTypeOff resolves an *rtype offset from a base type.
+//
+//go:linkname reflect_resolveTypeOff reflect.resolveTypeOff
+func reflect_resolveTypeOff(rtype unsafe.Pointer, off int32) unsafe.Pointer {
+	return unsafe.Pointer((*_type)(rtype).typeOff(typeOff(off)))
+}
+
+// reflect_resolveTextOff resolves a function pointer offset from a base type.
+//
+//go:linkname reflect_resolveTextOff reflect.resolveTextOff
+func reflect_resolveTextOff(rtype unsafe.Pointer, off int32) unsafe.Pointer {
+	return (*_type)(rtype).textOff(textOff(off))
+
+}
+
+// reflectlite_resolveNameOff resolves a name offset from a base pointer.
+//
+//go:linkname reflectlite_resolveNameOff internal/reflectlite.resolveNameOff
+func reflectlite_resolveNameOff(ptrInModule unsafe.Pointer, off int32) unsafe.Pointer {
+	return unsafe.Pointer(resolveNameOff(ptrInModule, nameOff(off)).bytes)
+}
+
+// reflectlite_resolveTypeOff resolves an *rtype offset from a base type.
+//
+//go:linkname reflectlite_resolveTypeOff internal/reflectlite.resolveTypeOff
+func reflectlite_resolveTypeOff(rtype unsafe.Pointer, off int32) unsafe.Pointer {
+	return unsafe.Pointer((*_type)(rtype).typeOff(typeOff(off)))
+}
+
+// reflect_addReflectOff adds a pointer to the reflection offset lookup map.
+//
+//go:linkname reflect_addReflectOff reflect.addReflectOff
+func reflect_addReflectOff(ptr unsafe.Pointer) int32 {
+	reflectOffsLock()
+	if reflectOffs.m == nil {
+		reflectOffs.m = make(map[int32]unsafe.Pointer)
+		reflectOffs.minv = make(map[unsafe.Pointer]int32)
+		reflectOffs.next = -1
+	}
+	id, found := reflectOffs.minv[ptr]
+	if !found {
+		id = reflectOffs.next
+		reflectOffs.next-- // use negative offsets as IDs to aid debugging
+		reflectOffs.m[id] = ptr
+		reflectOffs.minv[ptr] = id
+	}
+	reflectOffsUnlock()
+	return id
+}
diff --git a/contrib/go/_std_1.19/src/runtime/runtime2.go b/contrib/go/_std_1.19/src/runtime/runtime2.go
new file mode 100644
index 0000000000..e1788223e7
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/runtime2.go
@@ -0,0 +1,1151 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"internal/goarch"
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+// defined constants
+const (
+	// G status
+	//
+	// Beyond indicating the general state of a G, the G status
+	// acts like a lock on the goroutine's stack (and hence its
+	// ability to execute user code).
+	//
+	// If you add to this list, add to the list
+	// of "okay during garbage collection" status
+	// in mgcmark.go too.
+	//
+	// TODO(austin): The _Gscan bit could be much lighter-weight.
+	// For example, we could choose not to run _Gscanrunnable
+	// goroutines found in the run queue, rather than CAS-looping
+	// until they become _Grunnable. And transitions like
+	// _Gscanwaiting -> _Gscanrunnable are actually okay because
+	// they don't affect stack ownership.
+
+	// _Gidle means this goroutine was just allocated and has not
+	// yet been initialized.
+	_Gidle = iota // 0
+
+	// _Grunnable means this goroutine is on a run queue. It is
+	// not currently executing user code. The stack is not owned.
+	_Grunnable // 1
+
+	// _Grunning means this goroutine may execute user code. The
+	// stack is owned by this goroutine. It is not on a run queue.
+	// It is assigned an M and a P (g.m and g.m.p are valid).
+	_Grunning // 2
+
+	// _Gsyscall means this goroutine is executing a system call.
+	// It is not executing user code. The stack is owned by this
+	// goroutine. It is not on a run queue. It is assigned an M.
+	_Gsyscall // 3
+
+	// _Gwaiting means this goroutine is blocked in the runtime.
+	// It is not executing user code. It is not on a run queue,
+	// but should be recorded somewhere (e.g., a channel wait
+	// queue) so it can be ready()d when necessary. The stack is
+	// not owned *except* that a channel operation may read or
+	// write parts of the stack under the appropriate channel
+	// lock. Otherwise, it is not safe to access the stack after a
+	// goroutine enters _Gwaiting (e.g., it may get moved).
+	_Gwaiting // 4
+
+	// _Gmoribund_unused is currently unused, but hardcoded in gdb
+	// scripts.
+	_Gmoribund_unused // 5
+
+	// _Gdead means this goroutine is currently unused. It may be
+	// just exited, on a free list, or just being initialized. It
+	// is not executing user code. It may or may not have a stack
+	// allocated. The G and its stack (if any) are owned by the M
+	// that is exiting the G or that obtained the G from the free
+	// list.
+	_Gdead // 6
+
+	// _Genqueue_unused is currently unused.
+	_Genqueue_unused // 7
+
+	// _Gcopystack means this goroutine's stack is being moved. It
+	// is not executing user code and is not on a run queue. The
+	// stack is owned by the goroutine that put it in _Gcopystack.
+	_Gcopystack // 8
+
+	// _Gpreempted means this goroutine stopped itself for a
+	// suspendG preemption. It is like _Gwaiting, but nothing is
+	// yet responsible for ready()ing it. Some suspendG must CAS
+	// the status to _Gwaiting to take responsibility for
+	// ready()ing this G.
+	_Gpreempted // 9
+
+	// _Gscan combined with one of the above states other than
+	// _Grunning indicates that GC is scanning the stack. The
+	// goroutine is not executing user code and the stack is owned
+	// by the goroutine that set the _Gscan bit.
+	//
+	// _Gscanrunning is different: it is used to briefly block
+	// state transitions while GC signals the G to scan its own
+	// stack. This is otherwise like _Grunning.
+	//
+	// atomicstatus&~Gscan gives the state the goroutine will
+	// return to when the scan completes.
+	_Gscan          = 0x1000
+	_Gscanrunnable  = _Gscan + _Grunnable  // 0x1001
+	_Gscanrunning   = _Gscan + _Grunning   // 0x1002
+	_Gscansyscall   = _Gscan + _Gsyscall   // 0x1003
+	_Gscanwaiting   = _Gscan + _Gwaiting   // 0x1004
+	_Gscanpreempted = _Gscan + _Gpreempted // 0x1009
+)
+
+const (
+	// P status
+
+	// _Pidle means a P is not being used to run user code or the
+	// scheduler. Typically, it's on the idle P list and available
+	// to the scheduler, but it may just be transitioning between
+	// other states.
+	//
+	// The P is owned by the idle list or by whatever is
+	// transitioning its state. Its run queue is empty.
+	_Pidle = iota
+
+	// _Prunning means a P is owned by an M and is being used to
+	// run user code or the scheduler. Only the M that owns this P
+	// is allowed to change the P's status from _Prunning. The M
+	// may transition the P to _Pidle (if it has no more work to
+	// do), _Psyscall (when entering a syscall), or _Pgcstop (to
+	// halt for the GC). The M may also hand ownership of the P
+	// off directly to another M (e.g., to schedule a locked G).
+	_Prunning
+
+	// _Psyscall means a P is not running user code. It has
+	// affinity to an M in a syscall but is not owned by it and
+	// may be stolen by another M. This is similar to _Pidle but
+	// uses lightweight transitions and maintains M affinity.
+	//
+	// Leaving _Psyscall must be done with a CAS, either to steal
+	// or retake the P. Note that there's an ABA hazard: even if
+	// an M successfully CASes its original P back to _Prunning
+	// after a syscall, it must understand the P may have been
+	// used by another M in the interim.
+	_Psyscall
+
+	// _Pgcstop means a P is halted for STW and owned by the M
+	// that stopped the world. The M that stopped the world
+	// continues to use its P, even in _Pgcstop. Transitioning
+	// from _Prunning to _Pgcstop causes an M to release its P and
+	// park.
+	//
+	// The P retains its run queue and startTheWorld will restart
+	// the scheduler on Ps with non-empty run queues.
+	_Pgcstop
+
+	// _Pdead means a P is no longer used (GOMAXPROCS shrank). We
+	// reuse Ps if GOMAXPROCS increases. A dead P is mostly
+	// stripped of its resources, though a few things remain
+	// (e.g., trace buffers).
+	_Pdead
+)
+
+// Mutual exclusion locks.  In the uncontended case,
+// as fast as spin locks (just a few user-level instructions),
+// but on the contention path they sleep in the kernel.
+// A zeroed Mutex is unlocked (no need to initialize each lock).
+// Initialization is helpful for static lock ranking, but not required.
+type mutex struct {
+	// Empty struct if lock ranking is disabled, otherwise includes the lock rank
+	lockRankStruct
+	// Futex-based impl treats it as uint32 key,
+	// while sema-based impl as M* waitm.
+	// Used to be a union, but unions break precise GC.
+	key uintptr
+}
+
+// sleep and wakeup on one-time events.
+// before any calls to notesleep or notewakeup,
+// must call noteclear to initialize the Note.
+// then, exactly one thread can call notesleep
+// and exactly one thread can call notewakeup (once).
+// once notewakeup has been called, the notesleep
+// will return.  future notesleep will return immediately.
+// subsequent noteclear must be called only after
+// previous notesleep has returned, e.g. it's disallowed
+// to call noteclear straight after notewakeup.
+//
+// notetsleep is like notesleep but wakes up after
+// a given number of nanoseconds even if the event
+// has not yet happened.  if a goroutine uses notetsleep to
+// wake up early, it must wait to call noteclear until it
+// can be sure that no other goroutine is calling
+// notewakeup.
+//
+// notesleep/notetsleep are generally called on g0,
+// notetsleepg is similar to notetsleep but is called on user g.
+type note struct {
+	// Futex-based impl treats it as uint32 key,
+	// while sema-based impl as M* waitm.
+	// Used to be a union, but unions break precise GC.
+	key uintptr
+}
+
+type funcval struct {
+	fn uintptr
+	// variable-size, fn-specific data here
+}
+
+type iface struct {
+	tab  *itab
+	data unsafe.Pointer
+}
+
+type eface struct {
+	_type *_type
+	data  unsafe.Pointer
+}
+
+func efaceOf(ep *any) *eface {
+	return (*eface)(unsafe.Pointer(ep))
+}
+
+// The guintptr, muintptr, and puintptr are all used to bypass write barriers.
+// It is particularly important to avoid write barriers when the current P has
+// been released, because the GC thinks the world is stopped, and an
+// unexpected write barrier would not be synchronized with the GC,
+// which can lead to a half-executed write barrier that has marked the object
+// but not queued it. If the GC skips the object and completes before the
+// queuing can occur, it will incorrectly free the object.
+//
+// We tried using special assignment functions invoked only when not
+// holding a running P, but then some updates to a particular memory
+// word went through write barriers and some did not. This breaks the
+// write barrier shadow checking mode, and it is also scary: better to have
+// a word that is completely ignored by the GC than to have one for which
+// only a few updates are ignored.
+//
+// Gs and Ps are always reachable via true pointers in the
+// allgs and allp lists or (during allocation before they reach those lists)
+// from stack variables.
+//
+// Ms are always reachable via true pointers either from allm or
+// freem. Unlike Gs and Ps we do free Ms, so it's important that
+// nothing ever hold an muintptr across a safe point.
+
+// A guintptr holds a goroutine pointer, but typed as a uintptr
+// to bypass write barriers. It is used in the Gobuf goroutine state
+// and in scheduling lists that are manipulated without a P.
+//
+// The Gobuf.g goroutine pointer is almost always updated by assembly code.
+// In one of the few places it is updated by Go code - func save - it must be
+// treated as a uintptr to avoid a write barrier being emitted at a bad time.
+// Instead of figuring out how to emit the write barriers missing in the
+// assembly manipulation, we change the type of the field to uintptr,
+// so that it does not require write barriers at all.
+//
+// Goroutine structs are published in the allg list and never freed.
+// That will keep the goroutine structs from being collected.
+// There is never a time that Gobuf.g's contain the only references
+// to a goroutine: the publishing of the goroutine in allg comes first.
+// Goroutine pointers are also kept in non-GC-visible places like TLS,
+// so I can't see them ever moving. If we did want to start moving data
+// in the GC, we'd need to allocate the goroutine structs from an
+// alternate arena. Using guintptr doesn't make that problem any worse.
+// Note that pollDesc.rg, pollDesc.wg also store g in uintptr form,
+// so they would need to be updated too if g's start moving.
+type guintptr uintptr
+
+//go:nosplit
+func (gp guintptr) ptr() *g { return (*g)(unsafe.Pointer(gp)) }
+
+//go:nosplit
+func (gp *guintptr) set(g *g) { *gp = guintptr(unsafe.Pointer(g)) }
+
+//go:nosplit
+func (gp *guintptr) cas(old, new guintptr) bool {
+	return atomic.Casuintptr((*uintptr)(unsafe.Pointer(gp)), uintptr(old), uintptr(new))
+}
+
+// setGNoWB performs *gp = new without a write barrier.
+// For times when it's impractical to use a guintptr.
+//
+//go:nosplit
+//go:nowritebarrier
+func setGNoWB(gp **g, new *g) {
+	(*guintptr)(unsafe.Pointer(gp)).set(new)
+}
+
+type puintptr uintptr
+
+//go:nosplit
+func (pp puintptr) ptr() *p { return (*p)(unsafe.Pointer(pp)) }
+
+//go:nosplit
+func (pp *puintptr) set(p *p) { *pp = puintptr(unsafe.Pointer(p)) }
+
+// muintptr is a *m that is not tracked by the garbage collector.
+//
+// Because we do free Ms, there are some additional constrains on
+// muintptrs:
+//
+//  1. Never hold an muintptr locally across a safe point.
+//
+//  2. Any muintptr in the heap must be owned by the M itself so it can
+//     ensure it is not in use when the last true *m is released.
+type muintptr uintptr
+
+//go:nosplit
+func (mp muintptr) ptr() *m { return (*m)(unsafe.Pointer(mp)) }
+
+//go:nosplit
+func (mp *muintptr) set(m *m) { *mp = muintptr(unsafe.Pointer(m)) }
+
+// setMNoWB performs *mp = new without a write barrier.
+// For times when it's impractical to use an muintptr.
+//
+//go:nosplit
+//go:nowritebarrier
+func setMNoWB(mp **m, new *m) {
+	(*muintptr)(unsafe.Pointer(mp)).set(new)
+}
+
+type gobuf struct {
+	// The offsets of sp, pc, and g are known to (hard-coded in) libmach.
+	//
+	// ctxt is unusual with respect to GC: it may be a
+	// heap-allocated funcval, so GC needs to track it, but it
+	// needs to be set and cleared from assembly, where it's
+	// difficult to have write barriers. However, ctxt is really a
+	// saved, live register, and we only ever exchange it between
+	// the real register and the gobuf. Hence, we treat it as a
+	// root during stack scanning, which means assembly that saves
+	// and restores it doesn't need write barriers. It's still
+	// typed as a pointer so that any other writes from Go get
+	// write barriers.
+	sp   uintptr
+	pc   uintptr
+	g    guintptr
+	ctxt unsafe.Pointer
+	ret  uintptr
+	lr   uintptr
+	bp   uintptr // for framepointer-enabled architectures
+}
+
+// sudog represents a g in a wait list, such as for sending/receiving
+// on a channel.
+//
+// sudog is necessary because the g ↔ synchronization object relation
+// is many-to-many. A g can be on many wait lists, so there may be
+// many sudogs for one g; and many gs may be waiting on the same
+// synchronization object, so there may be many sudogs for one object.
+//
+// sudogs are allocated from a special pool. Use acquireSudog and
+// releaseSudog to allocate and free them.
+type sudog struct {
+	// The following fields are protected by the hchan.lock of the
+	// channel this sudog is blocking on. shrinkstack depends on
+	// this for sudogs involved in channel ops.
+
+	g *g
+
+	next *sudog
+	prev *sudog
+	elem unsafe.Pointer // data element (may point to stack)
+
+	// The following fields are never accessed concurrently.
+	// For channels, waitlink is only accessed by g.
+	// For semaphores, all fields (including the ones above)
+	// are only accessed when holding a semaRoot lock.
+
+	acquiretime int64
+	releasetime int64
+	ticket      uint32
+
+	// isSelect indicates g is participating in a select, so
+	// g.selectDone must be CAS'd to win the wake-up race.
+	isSelect bool
+
+	// success indicates whether communication over channel c
+	// succeeded. It is true if the goroutine was awoken because a
+	// value was delivered over channel c, and false if awoken
+	// because c was closed.
+	success bool
+
+	parent   *sudog // semaRoot binary tree
+	waitlink *sudog // g.waiting list or semaRoot
+	waittail *sudog // semaRoot
+	c        *hchan // channel
+}
+
+type libcall struct {
+	fn   uintptr
+	n    uintptr // number of parameters
+	args uintptr // parameters
+	r1   uintptr // return values
+	r2   uintptr
+	err  uintptr // error number
+}
+
+// Stack describes a Go execution stack.
+// The bounds of the stack are exactly [lo, hi),
+// with no implicit data structures on either side.
+type stack struct {
+	lo uintptr
+	hi uintptr
+}
+
+// heldLockInfo gives info on a held lock and the rank of that lock
+type heldLockInfo struct {
+	lockAddr uintptr
+	rank     lockRank
+}
+
+type g struct {
+	// Stack parameters.
+	// stack describes the actual stack memory: [stack.lo, stack.hi).
+	// stackguard0 is the stack pointer compared in the Go stack growth prologue.
+	// It is stack.lo+StackGuard normally, but can be StackPreempt to trigger a preemption.
+	// stackguard1 is the stack pointer compared in the C stack growth prologue.
+	// It is stack.lo+StackGuard on g0 and gsignal stacks.
+	// It is ~0 on other goroutine stacks, to trigger a call to morestackc (and crash).
+	stack       stack   // offset known to runtime/cgo
+	stackguard0 uintptr // offset known to liblink
+	stackguard1 uintptr // offset known to liblink
+
+	_panic    *_panic // innermost panic - offset known to liblink
+	_defer    *_defer // innermost defer
+	m         *m      // current m; offset known to arm liblink
+	sched     gobuf
+	syscallsp uintptr // if status==Gsyscall, syscallsp = sched.sp to use during gc
+	syscallpc uintptr // if status==Gsyscall, syscallpc = sched.pc to use during gc
+	stktopsp  uintptr // expected sp at top of stack, to check in traceback
+	// param is a generic pointer parameter field used to pass
+	// values in particular contexts where other storage for the
+	// parameter would be difficult to find. It is currently used
+	// in three ways:
+	// 1. When a channel operation wakes up a blocked goroutine, it sets param to
+	//    point to the sudog of the completed blocking operation.
+	// 2. By gcAssistAlloc1 to signal back to its caller that the goroutine completed
+	//    the GC cycle. It is unsafe to do so in any other way, because the goroutine's
+	//    stack may have moved in the meantime.
+	// 3. By debugCallWrap to pass parameters to a new goroutine because allocating a
+	//    closure in the runtime is forbidden.
+	param        unsafe.Pointer
+	atomicstatus uint32
+	stackLock    uint32 // sigprof/scang lock; TODO: fold in to atomicstatus
+	goid         int64
+	schedlink    guintptr
+	waitsince    int64      // approx time when the g become blocked
+	waitreason   waitReason // if status==Gwaiting
+
+	preempt       bool // preemption signal, duplicates stackguard0 = stackpreempt
+	preemptStop   bool // transition to _Gpreempted on preemption; otherwise, just deschedule
+	preemptShrink bool // shrink stack at synchronous safe point
+
+	// asyncSafePoint is set if g is stopped at an asynchronous
+	// safe point. This means there are frames on the stack
+	// without precise pointer information.
+	asyncSafePoint bool
+
+	paniconfault bool // panic (instead of crash) on unexpected fault address
+	gcscandone   bool // g has scanned stack; protected by _Gscan bit in status
+	throwsplit   bool // must not split stack
+	// activeStackChans indicates that there are unlocked channels
+	// pointing into this goroutine's stack. If true, stack
+	// copying needs to acquire channel locks to protect these
+	// areas of the stack.
+	activeStackChans bool
+	// parkingOnChan indicates that the goroutine is about to
+	// park on a chansend or chanrecv. Used to signal an unsafe point
+	// for stack shrinking. It's a boolean value, but is updated atomically.
+	parkingOnChan uint8
+
+	raceignore     int8     // ignore race detection events
+	sysblocktraced bool     // StartTrace has emitted EvGoInSyscall about this goroutine
+	tracking       bool     // whether we're tracking this G for sched latency statistics
+	trackingSeq    uint8    // used to decide whether to track this G
+	runnableStamp  int64    // timestamp of when the G last became runnable, only used when tracking
+	runnableTime   int64    // the amount of time spent runnable, cleared when running, only used when tracking
+	sysexitticks   int64    // cputicks when syscall has returned (for tracing)
+	traceseq       uint64   // trace event sequencer
+	tracelastp     puintptr // last P emitted an event for this goroutine
+	lockedm        muintptr
+	sig            uint32
+	writebuf       []byte
+	sigcode0       uintptr
+	sigcode1       uintptr
+	sigpc          uintptr
+	gopc           uintptr         // pc of go statement that created this goroutine
+	ancestors      *[]ancestorInfo // ancestor information goroutine(s) that created this goroutine (only used if debug.tracebackancestors)
+	startpc        uintptr         // pc of goroutine function
+	racectx        uintptr
+	waiting        *sudog         // sudog structures this g is waiting on (that have a valid elem ptr); in lock order
+	cgoCtxt        []uintptr      // cgo traceback context
+	labels         unsafe.Pointer // profiler labels
+	timer          *timer         // cached timer for time.Sleep
+	selectDone     uint32         // are we participating in a select and did someone win the race?
+
+	// goroutineProfiled indicates the status of this goroutine's stack for the
+	// current in-progress goroutine profile
+	goroutineProfiled goroutineProfileStateHolder
+
+	// Per-G GC state
+
+	// gcAssistBytes is this G's GC assist credit in terms of
+	// bytes allocated. If this is positive, then the G has credit
+	// to allocate gcAssistBytes bytes without assisting. If this
+	// is negative, then the G must correct this by performing
+	// scan work. We track this in bytes to make it fast to update
+	// and check for debt in the malloc hot path. The assist ratio
+	// determines how this corresponds to scan work debt.
+	gcAssistBytes int64
+}
+
+// gTrackingPeriod is the number of transitions out of _Grunning between
+// latency tracking runs.
+const gTrackingPeriod = 8
+
+const (
+	// tlsSlots is the number of pointer-sized slots reserved for TLS on some platforms,
+	// like Windows.
+	tlsSlots = 6
+	tlsSize  = tlsSlots * goarch.PtrSize
+)
+
+type m struct {
+	g0      *g     // goroutine with scheduling stack
+	morebuf gobuf  // gobuf arg to morestack
+	divmod  uint32 // div/mod denominator for arm - known to liblink
+	_       uint32 // align next field to 8 bytes
+
+	// Fields not known to debuggers.
+	procid        uint64            // for debuggers, but offset not hard-coded
+	gsignal       *g                // signal-handling g
+	goSigStack    gsignalStack      // Go-allocated signal handling stack
+	sigmask       sigset            // storage for saved signal mask
+	tls           [tlsSlots]uintptr // thread-local storage (for x86 extern register)
+	mstartfn      func()
+	curg          *g       // current running goroutine
+	caughtsig     guintptr // goroutine running during fatal signal
+	p             puintptr // attached p for executing go code (nil if not executing go code)
+	nextp         puintptr
+	oldp          puintptr // the p that was attached before executing a syscall
+	id            int64
+	mallocing     int32
+	throwing      throwType
+	preemptoff    string // if != "", keep curg running on this m
+	locks         int32
+	dying         int32
+	profilehz     int32
+	spinning      bool // m is out of work and is actively looking for work
+	blocked       bool // m is blocked on a note
+	newSigstack   bool // minit on C thread called sigaltstack
+	printlock     int8
+	incgo         bool   // m is executing a cgo call
+	freeWait      uint32 // if == 0, safe to free g0 and delete m (atomic)
+	fastrand      uint64
+	needextram    bool
+	traceback     uint8
+	ncgocall      uint64      // number of cgo calls in total
+	ncgo          int32       // number of cgo calls currently in progress
+	cgoCallersUse uint32      // if non-zero, cgoCallers in use temporarily
+	cgoCallers    *cgoCallers // cgo traceback if crashing in cgo call
+	park          note
+	alllink       *m // on allm
+	schedlink     muintptr
+	lockedg       guintptr
+	createstack   [32]uintptr // stack that created this thread.
+	lockedExt     uint32      // tracking for external LockOSThread
+	lockedInt     uint32      // tracking for internal lockOSThread
+	nextwaitm     muintptr    // next m waiting for lock
+	waitunlockf   func(*g, unsafe.Pointer) bool
+	waitlock      unsafe.Pointer
+	waittraceev   byte
+	waittraceskip int
+	startingtrace bool
+	syscalltick   uint32
+	freelink      *m // on sched.freem
+
+	// these are here because they are too large to be on the stack
+	// of low-level NOSPLIT functions.
+	libcall   libcall
+	libcallpc uintptr // for cpu profiler
+	libcallsp uintptr
+	libcallg  guintptr
+	syscall   libcall // stores syscall parameters on windows
+
+	vdsoSP uintptr // SP for traceback while in VDSO call (0 if not in call)
+	vdsoPC uintptr // PC for traceback while in VDSO call
+
+	// preemptGen counts the number of completed preemption
+	// signals. This is used to detect when a preemption is
+	// requested, but fails. Accessed atomically.
+	preemptGen uint32
+
+	// Whether this is a pending preemption signal on this M.
+	// Accessed atomically.
+	signalPending uint32
+
+	dlogPerM
+
+	mOS
+
+	// Up to 10 locks held by this m, maintained by the lock ranking code.
+	locksHeldLen int
+	locksHeld    [10]heldLockInfo
+}
+
+type p struct {
+	id          int32
+	status      uint32 // one of pidle/prunning/...
+	link        puintptr
+	schedtick   uint32     // incremented on every scheduler call
+	syscalltick uint32     // incremented on every system call
+	sysmontick  sysmontick // last tick observed by sysmon
+	m           muintptr   // back-link to associated m (nil if idle)
+	mcache      *mcache
+	pcache      pageCache
+	raceprocctx uintptr
+
+	deferpool    []*_defer // pool of available defer structs (see panic.go)
+	deferpoolbuf [32]*_defer
+
+	// Cache of goroutine ids, amortizes accesses to runtime·sched.goidgen.
+	goidcache    uint64
+	goidcacheend uint64
+
+	// Queue of runnable goroutines. Accessed without lock.
+	runqhead uint32
+	runqtail uint32
+	runq     [256]guintptr
+	// runnext, if non-nil, is a runnable G that was ready'd by
+	// the current G and should be run next instead of what's in
+	// runq if there's time remaining in the running G's time
+	// slice. It will inherit the time left in the current time
+	// slice. If a set of goroutines is locked in a
+	// communicate-and-wait pattern, this schedules that set as a
+	// unit and eliminates the (potentially large) scheduling
+	// latency that otherwise arises from adding the ready'd
+	// goroutines to the end of the run queue.
+	//
+	// Note that while other P's may atomically CAS this to zero,
+	// only the owner P can CAS it to a valid G.
+	runnext guintptr
+
+	// Available G's (status == Gdead)
+	gFree struct {
+		gList
+		n int32
+	}
+
+	sudogcache []*sudog
+	sudogbuf   [128]*sudog
+
+	// Cache of mspan objects from the heap.
+	mspancache struct {
+		// We need an explicit length here because this field is used
+		// in allocation codepaths where write barriers are not allowed,
+		// and eliminating the write barrier/keeping it eliminated from
+		// slice updates is tricky, moreso than just managing the length
+		// ourselves.
+		len int
+		buf [128]*mspan
+	}
+
+	tracebuf traceBufPtr
+
+	// traceSweep indicates the sweep events should be traced.
+	// This is used to defer the sweep start event until a span
+	// has actually been swept.
+	traceSweep bool
+	// traceSwept and traceReclaimed track the number of bytes
+	// swept and reclaimed by sweeping in the current sweep loop.
+	traceSwept, traceReclaimed uintptr
+
+	palloc persistentAlloc // per-P to avoid mutex
+
+	_ uint32 // Alignment for atomic fields below
+
+	// The when field of the first entry on the timer heap.
+	// This is updated using atomic functions.
+	// This is 0 if the timer heap is empty.
+	timer0When uint64
+
+	// The earliest known nextwhen field of a timer with
+	// timerModifiedEarlier status. Because the timer may have been
+	// modified again, there need not be any timer with this value.
+	// This is updated using atomic functions.
+	// This is 0 if there are no timerModifiedEarlier timers.
+	timerModifiedEarliest uint64
+
+	// Per-P GC state
+	gcAssistTime         int64 // Nanoseconds in assistAlloc
+	gcFractionalMarkTime int64 // Nanoseconds in fractional mark worker (atomic)
+
+	// limiterEvent tracks events for the GC CPU limiter.
+	limiterEvent limiterEvent
+
+	// gcMarkWorkerMode is the mode for the next mark worker to run in.
+	// That is, this is used to communicate with the worker goroutine
+	// selected for immediate execution by
+	// gcController.findRunnableGCWorker. When scheduling other goroutines,
+	// this field must be set to gcMarkWorkerNotWorker.
+	gcMarkWorkerMode gcMarkWorkerMode
+	// gcMarkWorkerStartTime is the nanotime() at which the most recent
+	// mark worker started.
+	gcMarkWorkerStartTime int64
+
+	// gcw is this P's GC work buffer cache. The work buffer is
+	// filled by write barriers, drained by mutator assists, and
+	// disposed on certain GC state transitions.
+	gcw gcWork
+
+	// wbBuf is this P's GC write barrier buffer.
+	//
+	// TODO: Consider caching this in the running G.
+	wbBuf wbBuf
+
+	runSafePointFn uint32 // if 1, run sched.safePointFn at next safe point
+
+	// statsSeq is a counter indicating whether this P is currently
+	// writing any stats. Its value is even when not, odd when it is.
+	statsSeq uint32
+
+	// Lock for timers. We normally access the timers while running
+	// on this P, but the scheduler can also do it from a different P.
+	timersLock mutex
+
+	// Actions to take at some time. This is used to implement the
+	// standard library's time package.
+	// Must hold timersLock to access.
+	timers []*timer
+
+	// Number of timers in P's heap.
+	// Modified using atomic instructions.
+	numTimers uint32
+
+	// Number of timerDeleted timers in P's heap.
+	// Modified using atomic instructions.
+	deletedTimers uint32
+
+	// Race context used while executing timer functions.
+	timerRaceCtx uintptr
+
+	// maxStackScanDelta accumulates the amount of stack space held by
+	// live goroutines (i.e. those eligible for stack scanning).
+	// Flushed to gcController.maxStackScan once maxStackScanSlack
+	// or -maxStackScanSlack is reached.
+	maxStackScanDelta int64
+
+	// gc-time statistics about current goroutines
+	// Note that this differs from maxStackScan in that this
+	// accumulates the actual stack observed to be used at GC time (hi - sp),
+	// not an instantaneous measure of the total stack size that might need
+	// to be scanned (hi - lo).
+	scannedStackSize uint64 // stack size of goroutines scanned by this P
+	scannedStacks    uint64 // number of goroutines scanned by this P
+
+	// preempt is set to indicate that this P should be enter the
+	// scheduler ASAP (regardless of what G is running on it).
+	preempt bool
+
+	// Padding is no longer needed. False sharing is now not a worry because p is large enough
+	// that its size class is an integer multiple of the cache line size (for any of our architectures).
+}
+
+type schedt struct {
+	// accessed atomically. keep at top to ensure alignment on 32-bit systems.
+	goidgen   uint64
+	lastpoll  uint64 // time of last network poll, 0 if currently polling
+	pollUntil uint64 // time to which current poll is sleeping
+
+	lock mutex
+
+	// When increasing nmidle, nmidlelocked, nmsys, or nmfreed, be
+	// sure to call checkdead().
+
+	midle        muintptr // idle m's waiting for work
+	nmidle       int32    // number of idle m's waiting for work
+	nmidlelocked int32    // number of locked m's waiting for work
+	mnext        int64    // number of m's that have been created and next M ID
+	maxmcount    int32    // maximum number of m's allowed (or die)
+	nmsys        int32    // number of system m's not counted for deadlock
+	nmfreed      int64    // cumulative number of freed m's
+
+	ngsys uint32 // number of system goroutines; updated atomically
+
+	pidle      puintptr // idle p's
+	npidle     uint32
+	nmspinning uint32 // See "Worker thread parking/unparking" comment in proc.go.
+
+	// Global runnable queue.
+	runq     gQueue
+	runqsize int32
+
+	// disable controls selective disabling of the scheduler.
+	//
+	// Use schedEnableUser to control this.
+	//
+	// disable is protected by sched.lock.
+	disable struct {
+		// user disables scheduling of user goroutines.
+		user     bool
+		runnable gQueue // pending runnable Gs
+		n        int32  // length of runnable
+	}
+
+	// Global cache of dead G's.
+	gFree struct {
+		lock    mutex
+		stack   gList // Gs with stacks
+		noStack gList // Gs without stacks
+		n       int32
+	}
+
+	// Central cache of sudog structs.
+	sudoglock  mutex
+	sudogcache *sudog
+
+	// Central pool of available defer structs.
+	deferlock mutex
+	deferpool *_defer
+
+	// freem is the list of m's waiting to be freed when their
+	// m.exited is set. Linked through m.freelink.
+	freem *m
+
+	gcwaiting  uint32 // gc is waiting to run
+	stopwait   int32
+	stopnote   note
+	sysmonwait uint32
+	sysmonnote note
+
+	// safepointFn should be called on each P at the next GC
+	// safepoint if p.runSafePointFn is set.
+	safePointFn   func(*p)
+	safePointWait int32
+	safePointNote note
+
+	profilehz int32 // cpu profiling rate
+
+	procresizetime int64 // nanotime() of last change to gomaxprocs
+	totaltime      int64 // ∫gomaxprocs dt up to procresizetime
+
+	// sysmonlock protects sysmon's actions on the runtime.
+	//
+	// Acquire and hold this mutex to block sysmon from interacting
+	// with the rest of the runtime.
+	sysmonlock mutex
+
+	// timeToRun is a distribution of scheduling latencies, defined
+	// as the sum of time a G spends in the _Grunnable state before
+	// it transitions to _Grunning.
+	//
+	// timeToRun is protected by sched.lock.
+	timeToRun timeHistogram
+}
+
+// Values for the flags field of a sigTabT.
+const (
+	_SigNotify   = 1 << iota // let signal.Notify have signal, even if from kernel
+	_SigKill                 // if signal.Notify doesn't take it, exit quietly
+	_SigThrow                // if signal.Notify doesn't take it, exit loudly
+	_SigPanic                // if the signal is from the kernel, panic
+	_SigDefault              // if the signal isn't explicitly requested, don't monitor it
+	_SigGoExit               // cause all runtime procs to exit (only used on Plan 9).
+	_SigSetStack             // Don't explicitly install handler, but add SA_ONSTACK to existing libc handler
+	_SigUnblock              // always unblock; see blockableSig
+	_SigIgn                  // _SIG_DFL action is to ignore the signal
+)
+
+// Layout of in-memory per-function information prepared by linker
+// See https://golang.org/s/go12symtab.
+// Keep in sync with linker (../cmd/link/internal/ld/pcln.go:/pclntab)
+// and with package debug/gosym and with symtab.go in package runtime.
+type _func struct {
+	entryoff uint32 // start pc, as offset from moduledata.text/pcHeader.textStart
+	nameoff  int32  // function name
+
+	args        int32  // in/out args size
+	deferreturn uint32 // offset of start of a deferreturn call instruction from entry, if any.
+
+	pcsp      uint32
+	pcfile    uint32
+	pcln      uint32
+	npcdata   uint32
+	cuOffset  uint32 // runtime.cutab offset of this function's CU
+	funcID    funcID // set for certain special runtime functions
+	flag      funcFlag
+	_         [1]byte // pad
+	nfuncdata uint8   // must be last, must end on a uint32-aligned boundary
+}
+
+// Pseudo-Func that is returned for PCs that occur in inlined code.
+// A *Func can be either a *_func or a *funcinl, and they are distinguished
+// by the first uintptr.
+type funcinl struct {
+	ones  uint32  // set to ^0 to distinguish from _func
+	entry uintptr // entry of the real (the "outermost") frame
+	name  string
+	file  string
+	line  int
+}
+
+// layout of Itab known to compilers
+// allocated in non-garbage-collected memory
+// Needs to be in sync with
+// ../cmd/compile/internal/reflectdata/reflect.go:/^func.WriteTabs.
+type itab struct {
+	inter *interfacetype
+	_type *_type
+	hash  uint32 // copy of _type.hash. Used for type switches.
+	_     [4]byte
+	fun   [1]uintptr // variable sized. fun[0]==0 means _type does not implement inter.
+}
+
+// Lock-free stack node.
+// Also known to export_test.go.
+type lfnode struct {
+	next    uint64
+	pushcnt uintptr
+}
+
+type forcegcstate struct {
+	lock mutex
+	g    *g
+	idle uint32
+}
+
+// extendRandom extends the random numbers in r[:n] to the whole slice r.
+// Treats n<0 as n==0.
+func extendRandom(r []byte, n int) {
+	if n < 0 {
+		n = 0
+	}
+	for n < len(r) {
+		// Extend random bits using hash function & time seed
+		w := n
+		if w > 16 {
+			w = 16
+		}
+		h := memhash(unsafe.Pointer(&r[n-w]), uintptr(nanotime()), uintptr(w))
+		for i := 0; i < goarch.PtrSize && n < len(r); i++ {
+			r[n] = byte(h)
+			n++
+			h >>= 8
+		}
+	}
+}
+
+// A _defer holds an entry on the list of deferred calls.
+// If you add a field here, add code to clear it in deferProcStack.
+// This struct must match the code in cmd/compile/internal/ssagen/ssa.go:deferstruct
+// and cmd/compile/internal/ssagen/ssa.go:(*state).call.
+// Some defers will be allocated on the stack and some on the heap.
+// All defers are logically part of the stack, so write barriers to
+// initialize them are not required. All defers must be manually scanned,
+// and for heap defers, marked.
+type _defer struct {
+	started bool
+	heap    bool
+	// openDefer indicates that this _defer is for a frame with open-coded
+	// defers. We have only one defer record for the entire frame (which may
+	// currently have 0, 1, or more defers active).
+	openDefer bool
+	sp        uintptr // sp at time of defer
+	pc        uintptr // pc at time of defer
+	fn        func()  // can be nil for open-coded defers
+	_panic    *_panic // panic that is running defer
+	link      *_defer // next defer on G; can point to either heap or stack!
+
+	// If openDefer is true, the fields below record values about the stack
+	// frame and associated function that has the open-coded defer(s). sp
+	// above will be the sp for the frame, and pc will be address of the
+	// deferreturn call in the function.
+	fd   unsafe.Pointer // funcdata for the function associated with the frame
+	varp uintptr        // value of varp for the stack frame
+	// framepc is the current pc associated with the stack frame. Together,
+	// with sp above (which is the sp associated with the stack frame),
+	// framepc/sp can be used as pc/sp pair to continue a stack trace via
+	// gentraceback().
+	framepc uintptr
+}
+
+// A _panic holds information about an active panic.
+//
+// A _panic value must only ever live on the stack.
+//
+// The argp and link fields are stack pointers, but don't need special
+// handling during stack growth: because they are pointer-typed and
+// _panic values only live on the stack, regular stack pointer
+// adjustment takes care of them.
+type _panic struct {
+	argp      unsafe.Pointer // pointer to arguments of deferred call run during panic; cannot move - known to liblink
+	arg       any            // argument to panic
+	link      *_panic        // link to earlier panic
+	pc        uintptr        // where to return to in runtime if this panic is bypassed
+	sp        unsafe.Pointer // where to return to in runtime if this panic is bypassed
+	recovered bool           // whether this panic is over
+	aborted   bool           // the panic was aborted
+	goexit    bool
+}
+
+// stack traces
+type stkframe struct {
+	fn       funcInfo   // function being run
+	pc       uintptr    // program counter within fn
+	continpc uintptr    // program counter where execution can continue, or 0 if not
+	lr       uintptr    // program counter at caller aka link register
+	sp       uintptr    // stack pointer at pc
+	fp       uintptr    // stack pointer at caller aka frame pointer
+	varp     uintptr    // top of local variables
+	argp     uintptr    // pointer to function arguments
+	arglen   uintptr    // number of bytes at argp
+	argmap   *bitvector // force use of this argmap
+}
+
+// ancestorInfo records details of where a goroutine was started.
+type ancestorInfo struct {
+	pcs  []uintptr // pcs from the stack of this goroutine
+	goid int64     // goroutine id of this goroutine; original goroutine possibly dead
+	gopc uintptr   // pc of go statement that created this goroutine
+}
+
+const (
+	_TraceRuntimeFrames = 1 << iota // include frames for internal runtime functions.
+	_TraceTrap                      // the initial PC, SP are from a trap, not a return PC from a call
+	_TraceJumpStack                 // if traceback is on a systemstack, resume trace at g that called into it
+)
+
+// The maximum number of frames we print for a traceback
+const _TracebackMaxFrames = 100
+
+// A waitReason explains why a goroutine has been stopped.
+// See gopark. Do not re-use waitReasons, add new ones.
+type waitReason uint8
+
+const (
+	waitReasonZero                  waitReason = iota // ""
+	waitReasonGCAssistMarking                         // "GC assist marking"
+	waitReasonIOWait                                  // "IO wait"
+	waitReasonChanReceiveNilChan                      // "chan receive (nil chan)"
+	waitReasonChanSendNilChan                         // "chan send (nil chan)"
+	waitReasonDumpingHeap                             // "dumping heap"
+	waitReasonGarbageCollection                       // "garbage collection"
+	waitReasonGarbageCollectionScan                   // "garbage collection scan"
+	waitReasonPanicWait                               // "panicwait"
+	waitReasonSelect                                  // "select"
+	waitReasonSelectNoCases                           // "select (no cases)"
+	waitReasonGCAssistWait                            // "GC assist wait"
+	waitReasonGCSweepWait                             // "GC sweep wait"
+	waitReasonGCScavengeWait                          // "GC scavenge wait"
+	waitReasonChanReceive                             // "chan receive"
+	waitReasonChanSend                                // "chan send"
+	waitReasonFinalizerWait                           // "finalizer wait"
+	waitReasonForceGCIdle                             // "force gc (idle)"
+	waitReasonSemacquire                              // "semacquire"
+	waitReasonSleep                                   // "sleep"
+	waitReasonSyncCondWait                            // "sync.Cond.Wait"
+	waitReasonTimerGoroutineIdle                      // "timer goroutine (idle)"
+	waitReasonTraceReaderBlocked                      // "trace reader (blocked)"
+	waitReasonWaitForGCCycle                          // "wait for GC cycle"
+	waitReasonGCWorkerIdle                            // "GC worker (idle)"
+	waitReasonPreempted                               // "preempted"
+	waitReasonDebugCall                               // "debug call"
+)
+
+var waitReasonStrings = [...]string{
+	waitReasonZero:                  "",
+	waitReasonGCAssistMarking:       "GC assist marking",
+	waitReasonIOWait:                "IO wait",
+	waitReasonChanReceiveNilChan:    "chan receive (nil chan)",
+	waitReasonChanSendNilChan:       "chan send (nil chan)",
+	waitReasonDumpingHeap:           "dumping heap",
+	waitReasonGarbageCollection:     "garbage collection",
+	waitReasonGarbageCollectionScan: "garbage collection scan",
+	waitReasonPanicWait:             "panicwait",
+	waitReasonSelect:                "select",
+	waitReasonSelectNoCases:         "select (no cases)",
+	waitReasonGCAssistWait:          "GC assist wait",
+	waitReasonGCSweepWait:           "GC sweep wait",
+	waitReasonGCScavengeWait:        "GC scavenge wait",
+	waitReasonChanReceive:           "chan receive",
+	waitReasonChanSend:              "chan send",
+	waitReasonFinalizerWait:         "finalizer wait",
+	waitReasonForceGCIdle:           "force gc (idle)",
+	waitReasonSemacquire:            "semacquire",
+	waitReasonSleep:                 "sleep",
+	waitReasonSyncCondWait:          "sync.Cond.Wait",
+	waitReasonTimerGoroutineIdle:    "timer goroutine (idle)",
+	waitReasonTraceReaderBlocked:    "trace reader (blocked)",
+	waitReasonWaitForGCCycle:        "wait for GC cycle",
+	waitReasonGCWorkerIdle:          "GC worker (idle)",
+	waitReasonPreempted:             "preempted",
+	waitReasonDebugCall:             "debug call",
+}
+
+func (w waitReason) String() string {
+	if w < 0 || w >= waitReason(len(waitReasonStrings)) {
+		return "unknown wait reason"
+	}
+	return waitReasonStrings[w]
+}
+
+var (
+	allm       *m
+	gomaxprocs int32
+	ncpu       int32
+	forcegc    forcegcstate
+	sched      schedt
+	newprocs   int32
+
+	// allpLock protects P-less reads and size changes of allp, idlepMask,
+	// and timerpMask, and all writes to allp.
+	allpLock mutex
+	// len(allp) == gomaxprocs; may change at safe points, otherwise
+	// immutable.
+	allp []*p
+	// Bitmask of Ps in _Pidle list, one bit per P. Reads and writes must
+	// be atomic. Length may change at safe points.
+	//
+	// Each P must update only its own bit. In order to maintain
+	// consistency, a P going idle must the idle mask simultaneously with
+	// updates to the idle P list under the sched.lock, otherwise a racing
+	// pidleget may clear the mask before pidleput sets the mask,
+	// corrupting the bitmap.
+	//
+	// N.B., procresize takes ownership of all Ps in stopTheWorldWithSema.
+	idlepMask pMask
+	// Bitmask of Ps that may have a timer, one bit per P. Reads and writes
+	// must be atomic. Length may change at safe points.
+	timerpMask pMask
+
+	// Pool of GC parked background workers. Entries are type
+	// *gcBgMarkWorkerNode.
+	gcBgMarkWorkerPool lfstack
+
+	// Total number of gcBgMarkWorker goroutines. Protected by worldsema.
+	gcBgMarkWorkerCount int32
+
+	// Information about what cpu features are available.
+	// Packages outside the runtime should not use these
+	// as they are not an external api.
+	// Set on startup in asm_{386,amd64}.s
+	processorVersionInfo uint32
+	isIntel              bool
+
+	goarm uint8 // set by cmd/link on arm systems
+)
+
+// Set by the linker so the runtime can determine the buildmode.
+var (
+	islibrary bool // -buildmode=c-shared
+	isarchive bool // -buildmode=c-archive
+)
+
+// Must agree with internal/buildcfg.FramePointerEnabled.
+const framepointer_enabled = GOARCH == "amd64" || GOARCH == "arm64"
diff --git a/contrib/go/_std_1.19/src/runtime/runtime_boring.go b/contrib/go/_std_1.19/src/runtime/runtime_boring.go
new file mode 100644
index 0000000000..5a98b20253
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/runtime_boring.go
@@ -0,0 +1,19 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import _ "unsafe" // for go:linkname
+
+//go:linkname boring_runtime_arg0 crypto/internal/boring.runtime_arg0
+func boring_runtime_arg0() string {
+	// On Windows, argslice is not set, and it's too much work to find argv0.
+	if len(argslice) == 0 {
+		return ""
+	}
+	return argslice[0]
+}
+
+//go:linkname fipstls_runtime_arg0 crypto/internal/boring/fipstls.runtime_arg0
+func fipstls_runtime_arg0() string { return boring_runtime_arg0() }
diff --git a/contrib/go/_std_1.18/src/runtime/rwmutex.go b/contrib/go/_std_1.19/src/runtime/rwmutex.go
index 7713c3f1cc..7713c3f1cc 100644
--- a/contrib/go/_std_1.18/src/runtime/rwmutex.go
+++ b/contrib/go/_std_1.19/src/runtime/rwmutex.go
diff --git a/contrib/go/_std_1.18/src/runtime/select.go b/contrib/go/_std_1.19/src/runtime/select.go
index e18b2f14c0..e18b2f14c0 100644
--- a/contrib/go/_std_1.18/src/runtime/select.go
+++ b/contrib/go/_std_1.19/src/runtime/select.go
diff --git a/contrib/go/_std_1.19/src/runtime/sema.go b/contrib/go/_std_1.19/src/runtime/sema.go
new file mode 100644
index 0000000000..39935f70a9
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/sema.go
@@ -0,0 +1,623 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Semaphore implementation exposed to Go.
+// Intended use is provide a sleep and wakeup
+// primitive that can be used in the contended case
+// of other synchronization primitives.
+// Thus it targets the same goal as Linux's futex,
+// but it has much simpler semantics.
+//
+// That is, don't think of these as semaphores.
+// Think of them as a way to implement sleep and wakeup
+// such that every sleep is paired with a single wakeup,
+// even if, due to races, the wakeup happens before the sleep.
+//
+// See Mullender and Cox, ``Semaphores in Plan 9,''
+// https://swtch.com/semaphore.pdf
+
+package runtime
+
+import (
+	"internal/cpu"
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+// Asynchronous semaphore for sync.Mutex.
+
+// A semaRoot holds a balanced tree of sudog with distinct addresses (s.elem).
+// Each of those sudog may in turn point (through s.waitlink) to a list
+// of other sudogs waiting on the same address.
+// The operations on the inner lists of sudogs with the same address
+// are all O(1). The scanning of the top-level semaRoot list is O(log n),
+// where n is the number of distinct addresses with goroutines blocked
+// on them that hash to the given semaRoot.
+// See golang.org/issue/17953 for a program that worked badly
+// before we introduced the second level of list, and
+// BenchmarkSemTable/OneAddrCollision/* for a benchmark that exercises this.
+type semaRoot struct {
+	lock  mutex
+	treap *sudog // root of balanced tree of unique waiters.
+	nwait uint32 // Number of waiters. Read w/o the lock.
+}
+
+var semtable semTable
+
+// Prime to not correlate with any user patterns.
+const semTabSize = 251
+
+type semTable [semTabSize]struct {
+	root semaRoot
+	pad  [cpu.CacheLinePadSize - unsafe.Sizeof(semaRoot{})]byte
+}
+
+func (t *semTable) rootFor(addr *uint32) *semaRoot {
+	return &t[(uintptr(unsafe.Pointer(addr))>>3)%semTabSize].root
+}
+
+//go:linkname sync_runtime_Semacquire sync.runtime_Semacquire
+func sync_runtime_Semacquire(addr *uint32) {
+	semacquire1(addr, false, semaBlockProfile, 0)
+}
+
+//go:linkname poll_runtime_Semacquire internal/poll.runtime_Semacquire
+func poll_runtime_Semacquire(addr *uint32) {
+	semacquire1(addr, false, semaBlockProfile, 0)
+}
+
+//go:linkname sync_runtime_Semrelease sync.runtime_Semrelease
+func sync_runtime_Semrelease(addr *uint32, handoff bool, skipframes int) {
+	semrelease1(addr, handoff, skipframes)
+}
+
+//go:linkname sync_runtime_SemacquireMutex sync.runtime_SemacquireMutex
+func sync_runtime_SemacquireMutex(addr *uint32, lifo bool, skipframes int) {
+	semacquire1(addr, lifo, semaBlockProfile|semaMutexProfile, skipframes)
+}
+
+//go:linkname poll_runtime_Semrelease internal/poll.runtime_Semrelease
+func poll_runtime_Semrelease(addr *uint32) {
+	semrelease(addr)
+}
+
+func readyWithTime(s *sudog, traceskip int) {
+	if s.releasetime != 0 {
+		s.releasetime = cputicks()
+	}
+	goready(s.g, traceskip)
+}
+
+type semaProfileFlags int
+
+const (
+	semaBlockProfile semaProfileFlags = 1 << iota
+	semaMutexProfile
+)
+
+// Called from runtime.
+func semacquire(addr *uint32) {
+	semacquire1(addr, false, 0, 0)
+}
+
+func semacquire1(addr *uint32, lifo bool, profile semaProfileFlags, skipframes int) {
+	gp := getg()
+	if gp != gp.m.curg {
+		throw("semacquire not on the G stack")
+	}
+
+	// Easy case.
+	if cansemacquire(addr) {
+		return
+	}
+
+	// Harder case:
+	//	increment waiter count
+	//	try cansemacquire one more time, return if succeeded
+	//	enqueue itself as a waiter
+	//	sleep
+	//	(waiter descriptor is dequeued by signaler)
+	s := acquireSudog()
+	root := semtable.rootFor(addr)
+	t0 := int64(0)
+	s.releasetime = 0
+	s.acquiretime = 0
+	s.ticket = 0
+	if profile&semaBlockProfile != 0 && blockprofilerate > 0 {
+		t0 = cputicks()
+		s.releasetime = -1
+	}
+	if profile&semaMutexProfile != 0 && mutexprofilerate > 0 {
+		if t0 == 0 {
+			t0 = cputicks()
+		}
+		s.acquiretime = t0
+	}
+	for {
+		lockWithRank(&root.lock, lockRankRoot)
+		// Add ourselves to nwait to disable "easy case" in semrelease.
+		atomic.Xadd(&root.nwait, 1)
+		// Check cansemacquire to avoid missed wakeup.
+		if cansemacquire(addr) {
+			atomic.Xadd(&root.nwait, -1)
+			unlock(&root.lock)
+			break
+		}
+		// Any semrelease after the cansemacquire knows we're waiting
+		// (we set nwait above), so go to sleep.
+		root.queue(addr, s, lifo)
+		goparkunlock(&root.lock, waitReasonSemacquire, traceEvGoBlockSync, 4+skipframes)
+		if s.ticket != 0 || cansemacquire(addr) {
+			break
+		}
+	}
+	if s.releasetime > 0 {
+		blockevent(s.releasetime-t0, 3+skipframes)
+	}
+	releaseSudog(s)
+}
+
+func semrelease(addr *uint32) {
+	semrelease1(addr, false, 0)
+}
+
+func semrelease1(addr *uint32, handoff bool, skipframes int) {
+	root := semtable.rootFor(addr)
+	atomic.Xadd(addr, 1)
+
+	// Easy case: no waiters?
+	// This check must happen after the xadd, to avoid a missed wakeup
+	// (see loop in semacquire).
+	if atomic.Load(&root.nwait) == 0 {
+		return
+	}
+
+	// Harder case: search for a waiter and wake it.
+	lockWithRank(&root.lock, lockRankRoot)
+	if atomic.Load(&root.nwait) == 0 {
+		// The count is already consumed by another goroutine,
+		// so no need to wake up another goroutine.
+		unlock(&root.lock)
+		return
+	}
+	s, t0 := root.dequeue(addr)
+	if s != nil {
+		atomic.Xadd(&root.nwait, -1)
+	}
+	unlock(&root.lock)
+	if s != nil { // May be slow or even yield, so unlock first
+		acquiretime := s.acquiretime
+		if acquiretime != 0 {
+			mutexevent(t0-acquiretime, 3+skipframes)
+		}
+		if s.ticket != 0 {
+			throw("corrupted semaphore ticket")
+		}
+		if handoff && cansemacquire(addr) {
+			s.ticket = 1
+		}
+		readyWithTime(s, 5+skipframes)
+		if s.ticket == 1 && getg().m.locks == 0 {
+			// Direct G handoff
+			// readyWithTime has added the waiter G as runnext in the
+			// current P; we now call the scheduler so that we start running
+			// the waiter G immediately.
+			// Note that waiter inherits our time slice: this is desirable
+			// to avoid having a highly contended semaphore hog the P
+			// indefinitely. goyield is like Gosched, but it emits a
+			// "preempted" trace event instead and, more importantly, puts
+			// the current G on the local runq instead of the global one.
+			// We only do this in the starving regime (handoff=true), as in
+			// the non-starving case it is possible for a different waiter
+			// to acquire the semaphore while we are yielding/scheduling,
+			// and this would be wasteful. We wait instead to enter starving
+			// regime, and then we start to do direct handoffs of ticket and
+			// P.
+			// See issue 33747 for discussion.
+			goyield()
+		}
+	}
+}
+
+func cansemacquire(addr *uint32) bool {
+	for {
+		v := atomic.Load(addr)
+		if v == 0 {
+			return false
+		}
+		if atomic.Cas(addr, v, v-1) {
+			return true
+		}
+	}
+}
+
+// queue adds s to the blocked goroutines in semaRoot.
+func (root *semaRoot) queue(addr *uint32, s *sudog, lifo bool) {
+	s.g = getg()
+	s.elem = unsafe.Pointer(addr)
+	s.next = nil
+	s.prev = nil
+
+	var last *sudog
+	pt := &root.treap
+	for t := *pt; t != nil; t = *pt {
+		if t.elem == unsafe.Pointer(addr) {
+			// Already have addr in list.
+			if lifo {
+				// Substitute s in t's place in treap.
+				*pt = s
+				s.ticket = t.ticket
+				s.acquiretime = t.acquiretime
+				s.parent = t.parent
+				s.prev = t.prev
+				s.next = t.next
+				if s.prev != nil {
+					s.prev.parent = s
+				}
+				if s.next != nil {
+					s.next.parent = s
+				}
+				// Add t first in s's wait list.
+				s.waitlink = t
+				s.waittail = t.waittail
+				if s.waittail == nil {
+					s.waittail = t
+				}
+				t.parent = nil
+				t.prev = nil
+				t.next = nil
+				t.waittail = nil
+			} else {
+				// Add s to end of t's wait list.
+				if t.waittail == nil {
+					t.waitlink = s
+				} else {
+					t.waittail.waitlink = s
+				}
+				t.waittail = s
+				s.waitlink = nil
+			}
+			return
+		}
+		last = t
+		if uintptr(unsafe.Pointer(addr)) < uintptr(t.elem) {
+			pt = &t.prev
+		} else {
+			pt = &t.next
+		}
+	}
+
+	// Add s as new leaf in tree of unique addrs.
+	// The balanced tree is a treap using ticket as the random heap priority.
+	// That is, it is a binary tree ordered according to the elem addresses,
+	// but then among the space of possible binary trees respecting those
+	// addresses, it is kept balanced on average by maintaining a heap ordering
+	// on the ticket: s.ticket <= both s.prev.ticket and s.next.ticket.
+	// https://en.wikipedia.org/wiki/Treap
+	// https://faculty.washington.edu/aragon/pubs/rst89.pdf
+	//
+	// s.ticket compared with zero in couple of places, therefore set lowest bit.
+	// It will not affect treap's quality noticeably.
+	s.ticket = fastrand() | 1
+	s.parent = last
+	*pt = s
+
+	// Rotate up into tree according to ticket (priority).
+	for s.parent != nil && s.parent.ticket > s.ticket {
+		if s.parent.prev == s {
+			root.rotateRight(s.parent)
+		} else {
+			if s.parent.next != s {
+				panic("semaRoot queue")
+			}
+			root.rotateLeft(s.parent)
+		}
+	}
+}
+
+// dequeue searches for and finds the first goroutine
+// in semaRoot blocked on addr.
+// If the sudog was being profiled, dequeue returns the time
+// at which it was woken up as now. Otherwise now is 0.
+func (root *semaRoot) dequeue(addr *uint32) (found *sudog, now int64) {
+	ps := &root.treap
+	s := *ps
+	for ; s != nil; s = *ps {
+		if s.elem == unsafe.Pointer(addr) {
+			goto Found
+		}
+		if uintptr(unsafe.Pointer(addr)) < uintptr(s.elem) {
+			ps = &s.prev
+		} else {
+			ps = &s.next
+		}
+	}
+	return nil, 0
+
+Found:
+	now = int64(0)
+	if s.acquiretime != 0 {
+		now = cputicks()
+	}
+	if t := s.waitlink; t != nil {
+		// Substitute t, also waiting on addr, for s in root tree of unique addrs.
+		*ps = t
+		t.ticket = s.ticket
+		t.parent = s.parent
+		t.prev = s.prev
+		if t.prev != nil {
+			t.prev.parent = t
+		}
+		t.next = s.next
+		if t.next != nil {
+			t.next.parent = t
+		}
+		if t.waitlink != nil {
+			t.waittail = s.waittail
+		} else {
+			t.waittail = nil
+		}
+		t.acquiretime = now
+		s.waitlink = nil
+		s.waittail = nil
+	} else {
+		// Rotate s down to be leaf of tree for removal, respecting priorities.
+		for s.next != nil || s.prev != nil {
+			if s.next == nil || s.prev != nil && s.prev.ticket < s.next.ticket {
+				root.rotateRight(s)
+			} else {
+				root.rotateLeft(s)
+			}
+		}
+		// Remove s, now a leaf.
+		if s.parent != nil {
+			if s.parent.prev == s {
+				s.parent.prev = nil
+			} else {
+				s.parent.next = nil
+			}
+		} else {
+			root.treap = nil
+		}
+	}
+	s.parent = nil
+	s.elem = nil
+	s.next = nil
+	s.prev = nil
+	s.ticket = 0
+	return s, now
+}
+
+// rotateLeft rotates the tree rooted at node x.
+// turning (x a (y b c)) into (y (x a b) c).
+func (root *semaRoot) rotateLeft(x *sudog) {
+	// p -> (x a (y b c))
+	p := x.parent
+	y := x.next
+	b := y.prev
+
+	y.prev = x
+	x.parent = y
+	x.next = b
+	if b != nil {
+		b.parent = x
+	}
+
+	y.parent = p
+	if p == nil {
+		root.treap = y
+	} else if p.prev == x {
+		p.prev = y
+	} else {
+		if p.next != x {
+			throw("semaRoot rotateLeft")
+		}
+		p.next = y
+	}
+}
+
+// rotateRight rotates the tree rooted at node y.
+// turning (y (x a b) c) into (x a (y b c)).
+func (root *semaRoot) rotateRight(y *sudog) {
+	// p -> (y (x a b) c)
+	p := y.parent
+	x := y.prev
+	b := x.next
+
+	x.next = y
+	y.parent = x
+	y.prev = b
+	if b != nil {
+		b.parent = y
+	}
+
+	x.parent = p
+	if p == nil {
+		root.treap = x
+	} else if p.prev == y {
+		p.prev = x
+	} else {
+		if p.next != y {
+			throw("semaRoot rotateRight")
+		}
+		p.next = x
+	}
+}
+
+// notifyList is a ticket-based notification list used to implement sync.Cond.
+//
+// It must be kept in sync with the sync package.
+type notifyList struct {
+	// wait is the ticket number of the next waiter. It is atomically
+	// incremented outside the lock.
+	wait uint32
+
+	// notify is the ticket number of the next waiter to be notified. It can
+	// be read outside the lock, but is only written to with lock held.
+	//
+	// Both wait & notify can wrap around, and such cases will be correctly
+	// handled as long as their "unwrapped" difference is bounded by 2^31.
+	// For this not to be the case, we'd need to have 2^31+ goroutines
+	// blocked on the same condvar, which is currently not possible.
+	notify uint32
+
+	// List of parked waiters.
+	lock mutex
+	head *sudog
+	tail *sudog
+}
+
+// less checks if a < b, considering a & b running counts that may overflow the
+// 32-bit range, and that their "unwrapped" difference is always less than 2^31.
+func less(a, b uint32) bool {
+	return int32(a-b) < 0
+}
+
+// notifyListAdd adds the caller to a notify list such that it can receive
+// notifications. The caller must eventually call notifyListWait to wait for
+// such a notification, passing the returned ticket number.
+//
+//go:linkname notifyListAdd sync.runtime_notifyListAdd
+func notifyListAdd(l *notifyList) uint32 {
+	// This may be called concurrently, for example, when called from
+	// sync.Cond.Wait while holding a RWMutex in read mode.
+	return atomic.Xadd(&l.wait, 1) - 1
+}
+
+// notifyListWait waits for a notification. If one has been sent since
+// notifyListAdd was called, it returns immediately. Otherwise, it blocks.
+//
+//go:linkname notifyListWait sync.runtime_notifyListWait
+func notifyListWait(l *notifyList, t uint32) {
+	lockWithRank(&l.lock, lockRankNotifyList)
+
+	// Return right away if this ticket has already been notified.
+	if less(t, l.notify) {
+		unlock(&l.lock)
+		return
+	}
+
+	// Enqueue itself.
+	s := acquireSudog()
+	s.g = getg()
+	s.ticket = t
+	s.releasetime = 0
+	t0 := int64(0)
+	if blockprofilerate > 0 {
+		t0 = cputicks()
+		s.releasetime = -1
+	}
+	if l.tail == nil {
+		l.head = s
+	} else {
+		l.tail.next = s
+	}
+	l.tail = s
+	goparkunlock(&l.lock, waitReasonSyncCondWait, traceEvGoBlockCond, 3)
+	if t0 != 0 {
+		blockevent(s.releasetime-t0, 2)
+	}
+	releaseSudog(s)
+}
+
+// notifyListNotifyAll notifies all entries in the list.
+//
+//go:linkname notifyListNotifyAll sync.runtime_notifyListNotifyAll
+func notifyListNotifyAll(l *notifyList) {
+	// Fast-path: if there are no new waiters since the last notification
+	// we don't need to acquire the lock.
+	if atomic.Load(&l.wait) == atomic.Load(&l.notify) {
+		return
+	}
+
+	// Pull the list out into a local variable, waiters will be readied
+	// outside the lock.
+	lockWithRank(&l.lock, lockRankNotifyList)
+	s := l.head
+	l.head = nil
+	l.tail = nil
+
+	// Update the next ticket to be notified. We can set it to the current
+	// value of wait because any previous waiters are already in the list
+	// or will notice that they have already been notified when trying to
+	// add themselves to the list.
+	atomic.Store(&l.notify, atomic.Load(&l.wait))
+	unlock(&l.lock)
+
+	// Go through the local list and ready all waiters.
+	for s != nil {
+		next := s.next
+		s.next = nil
+		readyWithTime(s, 4)
+		s = next
+	}
+}
+
+// notifyListNotifyOne notifies one entry in the list.
+//
+//go:linkname notifyListNotifyOne sync.runtime_notifyListNotifyOne
+func notifyListNotifyOne(l *notifyList) {
+	// Fast-path: if there are no new waiters since the last notification
+	// we don't need to acquire the lock at all.
+	if atomic.Load(&l.wait) == atomic.Load(&l.notify) {
+		return
+	}
+
+	lockWithRank(&l.lock, lockRankNotifyList)
+
+	// Re-check under the lock if we need to do anything.
+	t := l.notify
+	if t == atomic.Load(&l.wait) {
+		unlock(&l.lock)
+		return
+	}
+
+	// Update the next notify ticket number.
+	atomic.Store(&l.notify, t+1)
+
+	// Try to find the g that needs to be notified.
+	// If it hasn't made it to the list yet we won't find it,
+	// but it won't park itself once it sees the new notify number.
+	//
+	// This scan looks linear but essentially always stops quickly.
+	// Because g's queue separately from taking numbers,
+	// there may be minor reorderings in the list, but we
+	// expect the g we're looking for to be near the front.
+	// The g has others in front of it on the list only to the
+	// extent that it lost the race, so the iteration will not
+	// be too long. This applies even when the g is missing:
+	// it hasn't yet gotten to sleep and has lost the race to
+	// the (few) other g's that we find on the list.
+	for p, s := (*sudog)(nil), l.head; s != nil; p, s = s, s.next {
+		if s.ticket == t {
+			n := s.next
+			if p != nil {
+				p.next = n
+			} else {
+				l.head = n
+			}
+			if n == nil {
+				l.tail = p
+			}
+			unlock(&l.lock)
+			s.next = nil
+			readyWithTime(s, 4)
+			return
+		}
+	}
+	unlock(&l.lock)
+}
+
+//go:linkname notifyListCheck sync.runtime_notifyListCheck
+func notifyListCheck(sz uintptr) {
+	if sz != unsafe.Sizeof(notifyList{}) {
+		print("runtime: bad notifyList size - sync=", sz, " runtime=", unsafe.Sizeof(notifyList{}), "\n")
+		throw("bad notifyList size")
+	}
+}
+
+//go:linkname sync_nanotime sync.runtime_nanotime
+func sync_nanotime() int64 {
+	return nanotime()
+}
diff --git a/contrib/go/_std_1.18/src/runtime/signal_amd64.go b/contrib/go/_std_1.19/src/runtime/signal_amd64.go
index 8ade208836..8ade208836 100644
--- a/contrib/go/_std_1.18/src/runtime/signal_amd64.go
+++ b/contrib/go/_std_1.19/src/runtime/signal_amd64.go
diff --git a/contrib/go/_std_1.18/src/runtime/signal_darwin.go b/contrib/go/_std_1.19/src/runtime/signal_darwin.go
index 8090fb22a5..8090fb22a5 100644
--- a/contrib/go/_std_1.18/src/runtime/signal_darwin.go
+++ b/contrib/go/_std_1.19/src/runtime/signal_darwin.go
diff --git a/contrib/go/_std_1.19/src/runtime/signal_darwin_amd64.go b/contrib/go/_std_1.19/src/runtime/signal_darwin_amd64.go
new file mode 100644
index 0000000000..20544d8489
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/signal_darwin_amd64.go
@@ -0,0 +1,96 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import "unsafe"
+
+type sigctxt struct {
+	info *siginfo
+	ctxt unsafe.Pointer
+}
+
+//go:nosplit
+//go:nowritebarrierrec
+func (c *sigctxt) regs() *regs64 { return &(*ucontext)(c.ctxt).uc_mcontext.ss }
+
+func (c *sigctxt) rax() uint64 { return c.regs().rax }
+func (c *sigctxt) rbx() uint64 { return c.regs().rbx }
+func (c *sigctxt) rcx() uint64 { return c.regs().rcx }
+func (c *sigctxt) rdx() uint64 { return c.regs().rdx }
+func (c *sigctxt) rdi() uint64 { return c.regs().rdi }
+func (c *sigctxt) rsi() uint64 { return c.regs().rsi }
+func (c *sigctxt) rbp() uint64 { return c.regs().rbp }
+func (c *sigctxt) rsp() uint64 { return c.regs().rsp }
+func (c *sigctxt) r8() uint64  { return c.regs().r8 }
+func (c *sigctxt) r9() uint64  { return c.regs().r9 }
+func (c *sigctxt) r10() uint64 { return c.regs().r10 }
+func (c *sigctxt) r11() uint64 { return c.regs().r11 }
+func (c *sigctxt) r12() uint64 { return c.regs().r12 }
+func (c *sigctxt) r13() uint64 { return c.regs().r13 }
+func (c *sigctxt) r14() uint64 { return c.regs().r14 }
+func (c *sigctxt) r15() uint64 { return c.regs().r15 }
+
+//go:nosplit
+//go:nowritebarrierrec
+func (c *sigctxt) rip() uint64 { return c.regs().rip }
+
+func (c *sigctxt) rflags() uint64  { return c.regs().rflags }
+func (c *sigctxt) cs() uint64      { return c.regs().cs }
+func (c *sigctxt) fs() uint64      { return c.regs().fs }
+func (c *sigctxt) gs() uint64      { return c.regs().gs }
+func (c *sigctxt) sigcode() uint64 { return uint64(c.info.si_code) }
+func (c *sigctxt) sigaddr() uint64 { return c.info.si_addr }
+
+func (c *sigctxt) set_rip(x uint64)     { c.regs().rip = x }
+func (c *sigctxt) set_rsp(x uint64)     { c.regs().rsp = x }
+func (c *sigctxt) set_sigcode(x uint64) { c.info.si_code = int32(x) }
+func (c *sigctxt) set_sigaddr(x uint64) { c.info.si_addr = x }
+
+//go:nosplit
+func (c *sigctxt) fixsigcode(sig uint32) {
+	switch sig {
+	case _SIGTRAP:
+		// OS X sets c.sigcode() == TRAP_BRKPT unconditionally for all SIGTRAPs,
+		// leaving no way to distinguish a breakpoint-induced SIGTRAP
+		// from an asynchronous signal SIGTRAP.
+		// They all look breakpoint-induced by default.
+		// Try looking at the code to see if it's a breakpoint.
+		// The assumption is that we're very unlikely to get an
+		// asynchronous SIGTRAP at just the moment that the
+		// PC started to point at unmapped memory.
+		pc := uintptr(c.rip())
+		// OS X will leave the pc just after the INT 3 instruction.
+		// INT 3 is usually 1 byte, but there is a 2-byte form.
+		code := (*[2]byte)(unsafe.Pointer(pc - 2))
+		if code[1] != 0xCC && (code[0] != 0xCD || code[1] != 3) {
+			// SIGTRAP on something other than INT 3.
+			c.set_sigcode(_SI_USER)
+		}
+
+	case _SIGSEGV:
+		// x86-64 has 48-bit virtual addresses. The top 16 bits must echo bit 47.
+		// The hardware delivers a different kind of fault for a malformed address
+		// than it does for an attempt to access a valid but unmapped address.
+		// OS X 10.9.2 mishandles the malformed address case, making it look like
+		// a user-generated signal (like someone ran kill -SEGV ourpid).
+		// We pass user-generated signals to os/signal, or else ignore them.
+		// Doing that here - and returning to the faulting code - results in an
+		// infinite loop. It appears the best we can do is rewrite what the kernel
+		// delivers into something more like the truth. The address used below
+		// has very little chance of being the one that caused the fault, but it is
+		// malformed, it is clearly not a real pointer, and if it does get printed
+		// in real life, people will probably search for it and find this code.
+		// There are no Google hits for b01dfacedebac1e or 0xb01dfacedebac1e
+		// as I type this comment.
+		//
+		// Note: if this code is removed, please consider
+		// enabling TestSignalForwardingGo for darwin-amd64 in
+		// misc/cgo/testcarchive/carchive_test.go.
+		if c.sigcode() == _SI_USER {
+			c.set_sigcode(_SI_USER + 1)
+			c.set_sigaddr(0xb01dfacedebac1e)
+		}
+	}
+}
diff --git a/contrib/go/_std_1.18/src/runtime/signal_linux_amd64.go b/contrib/go/_std_1.19/src/runtime/signal_linux_amd64.go
index 573b118397..573b118397 100644
--- a/contrib/go/_std_1.18/src/runtime/signal_linux_amd64.go
+++ b/contrib/go/_std_1.19/src/runtime/signal_linux_amd64.go
diff --git a/contrib/go/_std_1.19/src/runtime/signal_unix.go b/contrib/go/_std_1.19/src/runtime/signal_unix.go
new file mode 100644
index 0000000000..0be499b2e9
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/signal_unix.go
@@ -0,0 +1,1348 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix
+
+package runtime
+
+import (
+	"internal/abi"
+	"runtime/internal/atomic"
+	"runtime/internal/sys"
+	"unsafe"
+)
+
+// sigTabT is the type of an entry in the global sigtable array.
+// sigtable is inherently system dependent, and appears in OS-specific files,
+// but sigTabT is the same for all Unixy systems.
+// The sigtable array is indexed by a system signal number to get the flags
+// and printable name of each signal.
+type sigTabT struct {
+	flags int32
+	name  string
+}
+
+//go:linkname os_sigpipe os.sigpipe
+func os_sigpipe() {
+	systemstack(sigpipe)
+}
+
+func signame(sig uint32) string {
+	if sig >= uint32(len(sigtable)) {
+		return ""
+	}
+	return sigtable[sig].name
+}
+
+const (
+	_SIG_DFL uintptr = 0
+	_SIG_IGN uintptr = 1
+)
+
+// sigPreempt is the signal used for non-cooperative preemption.
+//
+// There's no good way to choose this signal, but there are some
+// heuristics:
+//
+// 1. It should be a signal that's passed-through by debuggers by
+// default. On Linux, this is SIGALRM, SIGURG, SIGCHLD, SIGIO,
+// SIGVTALRM, SIGPROF, and SIGWINCH, plus some glibc-internal signals.
+//
+// 2. It shouldn't be used internally by libc in mixed Go/C binaries
+// because libc may assume it's the only thing that can handle these
+// signals. For example SIGCANCEL or SIGSETXID.
+//
+// 3. It should be a signal that can happen spuriously without
+// consequences. For example, SIGALRM is a bad choice because the
+// signal handler can't tell if it was caused by the real process
+// alarm or not (arguably this means the signal is broken, but I
+// digress). SIGUSR1 and SIGUSR2 are also bad because those are often
+// used in meaningful ways by applications.
+//
+// 4. We need to deal with platforms without real-time signals (like
+// macOS), so those are out.
+//
+// We use SIGURG because it meets all of these criteria, is extremely
+// unlikely to be used by an application for its "real" meaning (both
+// because out-of-band data is basically unused and because SIGURG
+// doesn't report which socket has the condition, making it pretty
+// useless), and even if it is, the application has to be ready for
+// spurious SIGURG. SIGIO wouldn't be a bad choice either, but is more
+// likely to be used for real.
+const sigPreempt = _SIGURG
+
+// Stores the signal handlers registered before Go installed its own.
+// These signal handlers will be invoked in cases where Go doesn't want to
+// handle a particular signal (e.g., signal occurred on a non-Go thread).
+// See sigfwdgo for more information on when the signals are forwarded.
+//
+// This is read by the signal handler; accesses should use
+// atomic.Loaduintptr and atomic.Storeuintptr.
+var fwdSig [_NSIG]uintptr
+
+// handlingSig is indexed by signal number and is non-zero if we are
+// currently handling the signal. Or, to put it another way, whether
+// the signal handler is currently set to the Go signal handler or not.
+// This is uint32 rather than bool so that we can use atomic instructions.
+var handlingSig [_NSIG]uint32
+
+// channels for synchronizing signal mask updates with the signal mask
+// thread
+var (
+	disableSigChan  chan uint32
+	enableSigChan   chan uint32
+	maskUpdatedChan chan struct{}
+)
+
+func init() {
+	// _NSIG is the number of signals on this operating system.
+	// sigtable should describe what to do for all the possible signals.
+	if len(sigtable) != _NSIG {
+		print("runtime: len(sigtable)=", len(sigtable), " _NSIG=", _NSIG, "\n")
+		throw("bad sigtable len")
+	}
+}
+
+var signalsOK bool
+
+// Initialize signals.
+// Called by libpreinit so runtime may not be initialized.
+//
+//go:nosplit
+//go:nowritebarrierrec
+func initsig(preinit bool) {
+	if !preinit {
+		// It's now OK for signal handlers to run.
+		signalsOK = true
+	}
+
+	// For c-archive/c-shared this is called by libpreinit with
+	// preinit == true.
+	if (isarchive || islibrary) && !preinit {
+		return
+	}
+
+	for i := uint32(0); i < _NSIG; i++ {
+		t := &sigtable[i]
+		if t.flags == 0 || t.flags&_SigDefault != 0 {
+			continue
+		}
+
+		// We don't need to use atomic operations here because
+		// there shouldn't be any other goroutines running yet.
+		fwdSig[i] = getsig(i)
+
+		if !sigInstallGoHandler(i) {
+			// Even if we are not installing a signal handler,
+			// set SA_ONSTACK if necessary.
+			if fwdSig[i] != _SIG_DFL && fwdSig[i] != _SIG_IGN {
+				setsigstack(i)
+			} else if fwdSig[i] == _SIG_IGN {
+				sigInitIgnored(i)
+			}
+			continue
+		}
+
+		handlingSig[i] = 1
+		setsig(i, abi.FuncPCABIInternal(sighandler))
+	}
+}
+
+//go:nosplit
+//go:nowritebarrierrec
+func sigInstallGoHandler(sig uint32) bool {
+	// For some signals, we respect an inherited SIG_IGN handler
+	// rather than insist on installing our own default handler.
+	// Even these signals can be fetched using the os/signal package.
+	switch sig {
+	case _SIGHUP, _SIGINT:
+		if atomic.Loaduintptr(&fwdSig[sig]) == _SIG_IGN {
+			return false
+		}
+	}
+
+	if (GOOS == "linux" || GOOS == "android") && !iscgo && sig == sigPerThreadSyscall {
+		// sigPerThreadSyscall is the same signal used by glibc for
+		// per-thread syscalls on Linux. We use it for the same purpose
+		// in non-cgo binaries.
+		return true
+	}
+
+	t := &sigtable[sig]
+	if t.flags&_SigSetStack != 0 {
+		return false
+	}
+
+	// When built using c-archive or c-shared, only install signal
+	// handlers for synchronous signals and SIGPIPE and sigPreempt.
+	if (isarchive || islibrary) && t.flags&_SigPanic == 0 && sig != _SIGPIPE && sig != sigPreempt {
+		return false
+	}
+
+	return true
+}
+
+// sigenable enables the Go signal handler to catch the signal sig.
+// It is only called while holding the os/signal.handlers lock,
+// via os/signal.enableSignal and signal_enable.
+func sigenable(sig uint32) {
+	if sig >= uint32(len(sigtable)) {
+		return
+	}
+
+	// SIGPROF is handled specially for profiling.
+	if sig == _SIGPROF {
+		return
+	}
+
+	t := &sigtable[sig]
+	if t.flags&_SigNotify != 0 {
+		ensureSigM()
+		enableSigChan <- sig
+		<-maskUpdatedChan
+		if atomic.Cas(&handlingSig[sig], 0, 1) {
+			atomic.Storeuintptr(&fwdSig[sig], getsig(sig))
+			setsig(sig, abi.FuncPCABIInternal(sighandler))
+		}
+	}
+}
+
+// sigdisable disables the Go signal handler for the signal sig.
+// It is only called while holding the os/signal.handlers lock,
+// via os/signal.disableSignal and signal_disable.
+func sigdisable(sig uint32) {
+	if sig >= uint32(len(sigtable)) {
+		return
+	}
+
+	// SIGPROF is handled specially for profiling.
+	if sig == _SIGPROF {
+		return
+	}
+
+	t := &sigtable[sig]
+	if t.flags&_SigNotify != 0 {
+		ensureSigM()
+		disableSigChan <- sig
+		<-maskUpdatedChan
+
+		// If initsig does not install a signal handler for a
+		// signal, then to go back to the state before Notify
+		// we should remove the one we installed.
+		if !sigInstallGoHandler(sig) {
+			atomic.Store(&handlingSig[sig], 0)
+			setsig(sig, atomic.Loaduintptr(&fwdSig[sig]))
+		}
+	}
+}
+
+// sigignore ignores the signal sig.
+// It is only called while holding the os/signal.handlers lock,
+// via os/signal.ignoreSignal and signal_ignore.
+func sigignore(sig uint32) {
+	if sig >= uint32(len(sigtable)) {
+		return
+	}
+
+	// SIGPROF is handled specially for profiling.
+	if sig == _SIGPROF {
+		return
+	}
+
+	t := &sigtable[sig]
+	if t.flags&_SigNotify != 0 {
+		atomic.Store(&handlingSig[sig], 0)
+		setsig(sig, _SIG_IGN)
+	}
+}
+
+// clearSignalHandlers clears all signal handlers that are not ignored
+// back to the default. This is called by the child after a fork, so that
+// we can enable the signal mask for the exec without worrying about
+// running a signal handler in the child.
+//
+//go:nosplit
+//go:nowritebarrierrec
+func clearSignalHandlers() {
+	for i := uint32(0); i < _NSIG; i++ {
+		if atomic.Load(&handlingSig[i]) != 0 {
+			setsig(i, _SIG_DFL)
+		}
+	}
+}
+
+// setProcessCPUProfilerTimer is called when the profiling timer changes.
+// It is called with prof.signalLock held. hz is the new timer, and is 0 if
+// profiling is being disabled. Enable or disable the signal as
+// required for -buildmode=c-archive.
+func setProcessCPUProfilerTimer(hz int32) {
+	if hz != 0 {
+		// Enable the Go signal handler if not enabled.
+		if atomic.Cas(&handlingSig[_SIGPROF], 0, 1) {
+			h := getsig(_SIGPROF)
+			// If no signal handler was installed before, then we record
+			// _SIG_IGN here. When we turn off profiling (below) we'll start
+			// ignoring SIGPROF signals. We do this, rather than change
+			// to SIG_DFL, because there may be a pending SIGPROF
+			// signal that has not yet been delivered to some other thread.
+			// If we change to SIG_DFL when turning off profiling, the
+			// program will crash when that SIGPROF is delivered. We assume
+			// that programs that use profiling don't want to crash on a
+			// stray SIGPROF. See issue 19320.
+			// We do the change here instead of when turning off profiling,
+			// because there we may race with a signal handler running
+			// concurrently, in particular, sigfwdgo may observe _SIG_DFL and
+			// die. See issue 43828.
+			if h == _SIG_DFL {
+				h = _SIG_IGN
+			}
+			atomic.Storeuintptr(&fwdSig[_SIGPROF], h)
+			setsig(_SIGPROF, abi.FuncPCABIInternal(sighandler))
+		}
+
+		var it itimerval
+		it.it_interval.tv_sec = 0
+		it.it_interval.set_usec(1000000 / hz)
+		it.it_value = it.it_interval
+		setitimer(_ITIMER_PROF, &it, nil)
+	} else {
+		setitimer(_ITIMER_PROF, &itimerval{}, nil)
+
+		// If the Go signal handler should be disabled by default,
+		// switch back to the signal handler that was installed
+		// when we enabled profiling. We don't try to handle the case
+		// of a program that changes the SIGPROF handler while Go
+		// profiling is enabled.
+		if !sigInstallGoHandler(_SIGPROF) {
+			if atomic.Cas(&handlingSig[_SIGPROF], 1, 0) {
+				h := atomic.Loaduintptr(&fwdSig[_SIGPROF])
+				setsig(_SIGPROF, h)
+			}
+		}
+	}
+}
+
+// setThreadCPUProfilerHz makes any thread-specific changes required to
+// implement profiling at a rate of hz.
+// No changes required on Unix systems when using setitimer.
+func setThreadCPUProfilerHz(hz int32) {
+	getg().m.profilehz = hz
+}
+
+func sigpipe() {
+	if signal_ignored(_SIGPIPE) || sigsend(_SIGPIPE) {
+		return
+	}
+	dieFromSignal(_SIGPIPE)
+}
+
+// doSigPreempt handles a preemption signal on gp.
+func doSigPreempt(gp *g, ctxt *sigctxt) {
+	// Check if this G wants to be preempted and is safe to
+	// preempt.
+	if wantAsyncPreempt(gp) {
+		if ok, newpc := isAsyncSafePoint(gp, ctxt.sigpc(), ctxt.sigsp(), ctxt.siglr()); ok {
+			// Adjust the PC and inject a call to asyncPreempt.
+			ctxt.pushCall(abi.FuncPCABI0(asyncPreempt), newpc)
+		}
+	}
+
+	// Acknowledge the preemption.
+	atomic.Xadd(&gp.m.preemptGen, 1)
+	atomic.Store(&gp.m.signalPending, 0)
+
+	if GOOS == "darwin" || GOOS == "ios" {
+		atomic.Xadd(&pendingPreemptSignals, -1)
+	}
+}
+
+const preemptMSupported = true
+
+// preemptM sends a preemption request to mp. This request may be
+// handled asynchronously and may be coalesced with other requests to
+// the M. When the request is received, if the running G or P are
+// marked for preemption and the goroutine is at an asynchronous
+// safe-point, it will preempt the goroutine. It always atomically
+// increments mp.preemptGen after handling a preemption request.
+func preemptM(mp *m) {
+	// On Darwin, don't try to preempt threads during exec.
+	// Issue #41702.
+	if GOOS == "darwin" || GOOS == "ios" {
+		execLock.rlock()
+	}
+
+	if atomic.Cas(&mp.signalPending, 0, 1) {
+		if GOOS == "darwin" || GOOS == "ios" {
+			atomic.Xadd(&pendingPreemptSignals, 1)
+		}
+
+		// If multiple threads are preempting the same M, it may send many
+		// signals to the same M such that it hardly make progress, causing
+		// live-lock problem. Apparently this could happen on darwin. See
+		// issue #37741.
+		// Only send a signal if there isn't already one pending.
+		signalM(mp, sigPreempt)
+	}
+
+	if GOOS == "darwin" || GOOS == "ios" {
+		execLock.runlock()
+	}
+}
+
+// sigFetchG fetches the value of G safely when running in a signal handler.
+// On some architectures, the g value may be clobbered when running in a VDSO.
+// See issue #32912.
+//
+//go:nosplit
+func sigFetchG(c *sigctxt) *g {
+	switch GOARCH {
+	case "arm", "arm64", "ppc64", "ppc64le", "riscv64", "s390x":
+		if !iscgo && inVDSOPage(c.sigpc()) {
+			// When using cgo, we save the g on TLS and load it from there
+			// in sigtramp. Just use that.
+			// Otherwise, before making a VDSO call we save the g to the
+			// bottom of the signal stack. Fetch from there.
+			// TODO: in efence mode, stack is sysAlloc'd, so this wouldn't
+			// work.
+			sp := getcallersp()
+			s := spanOf(sp)
+			if s != nil && s.state.get() == mSpanManual && s.base() < sp && sp < s.limit {
+				gp := *(**g)(unsafe.Pointer(s.base()))
+				return gp
+			}
+			return nil
+		}
+	}
+	return getg()
+}
+
+// sigtrampgo is called from the signal handler function, sigtramp,
+// written in assembly code.
+// This is called by the signal handler, and the world may be stopped.
+//
+// It must be nosplit because getg() is still the G that was running
+// (if any) when the signal was delivered, but it's (usually) called
+// on the gsignal stack. Until this switches the G to gsignal, the
+// stack bounds check won't work.
+//
+//go:nosplit
+//go:nowritebarrierrec
+func sigtrampgo(sig uint32, info *siginfo, ctx unsafe.Pointer) {
+	if sigfwdgo(sig, info, ctx) {
+		return
+	}
+	c := &sigctxt{info, ctx}
+	g := sigFetchG(c)
+	setg(g)
+	if g == nil {
+		if sig == _SIGPROF {
+			// Some platforms (Linux) have per-thread timers, which we use in
+			// combination with the process-wide timer. Avoid double-counting.
+			if validSIGPROF(nil, c) {
+				sigprofNonGoPC(c.sigpc())
+			}
+			return
+		}
+		if sig == sigPreempt && preemptMSupported && debug.asyncpreemptoff == 0 {
+			// This is probably a signal from preemptM sent
+			// while executing Go code but received while
+			// executing non-Go code.
+			// We got past sigfwdgo, so we know that there is
+			// no non-Go signal handler for sigPreempt.
+			// The default behavior for sigPreempt is to ignore
+			// the signal, so badsignal will be a no-op anyway.
+			if GOOS == "darwin" || GOOS == "ios" {
+				atomic.Xadd(&pendingPreemptSignals, -1)
+			}
+			return
+		}
+		c.fixsigcode(sig)
+		badsignal(uintptr(sig), c)
+		return
+	}
+
+	setg(g.m.gsignal)
+
+	// If some non-Go code called sigaltstack, adjust.
+	var gsignalStack gsignalStack
+	setStack := adjustSignalStack(sig, g.m, &gsignalStack)
+	if setStack {
+		g.m.gsignal.stktopsp = getcallersp()
+	}
+
+	if g.stackguard0 == stackFork {
+		signalDuringFork(sig)
+	}
+
+	c.fixsigcode(sig)
+	sighandler(sig, info, ctx, g)
+	setg(g)
+	if setStack {
+		restoreGsignalStack(&gsignalStack)
+	}
+}
+
+// If the signal handler receives a SIGPROF signal on a non-Go thread,
+// it tries to collect a traceback into sigprofCallers.
+// sigprofCallersUse is set to non-zero while sigprofCallers holds a traceback.
+var sigprofCallers cgoCallers
+var sigprofCallersUse uint32
+
+// sigprofNonGo is called if we receive a SIGPROF signal on a non-Go thread,
+// and the signal handler collected a stack trace in sigprofCallers.
+// When this is called, sigprofCallersUse will be non-zero.
+// g is nil, and what we can do is very limited.
+//
+// It is called from the signal handling functions written in assembly code that
+// are active for cgo programs, cgoSigtramp and sigprofNonGoWrapper, which have
+// not verified that the SIGPROF delivery corresponds to the best available
+// profiling source for this thread.
+//
+//go:nosplit
+//go:nowritebarrierrec
+func sigprofNonGo(sig uint32, info *siginfo, ctx unsafe.Pointer) {
+	if prof.hz != 0 {
+		c := &sigctxt{info, ctx}
+		// Some platforms (Linux) have per-thread timers, which we use in
+		// combination with the process-wide timer. Avoid double-counting.
+		if validSIGPROF(nil, c) {
+			n := 0
+			for n < len(sigprofCallers) && sigprofCallers[n] != 0 {
+				n++
+			}
+			cpuprof.addNonGo(sigprofCallers[:n])
+		}
+	}
+
+	atomic.Store(&sigprofCallersUse, 0)
+}
+
+// sigprofNonGoPC is called when a profiling signal arrived on a
+// non-Go thread and we have a single PC value, not a stack trace.
+// g is nil, and what we can do is very limited.
+//
+//go:nosplit
+//go:nowritebarrierrec
+func sigprofNonGoPC(pc uintptr) {
+	if prof.hz != 0 {
+		stk := []uintptr{
+			pc,
+			abi.FuncPCABIInternal(_ExternalCode) + sys.PCQuantum,
+		}
+		cpuprof.addNonGo(stk)
+	}
+}
+
+// adjustSignalStack adjusts the current stack guard based on the
+// stack pointer that is actually in use while handling a signal.
+// We do this in case some non-Go code called sigaltstack.
+// This reports whether the stack was adjusted, and if so stores the old
+// signal stack in *gsigstack.
+//
+//go:nosplit
+func adjustSignalStack(sig uint32, mp *m, gsigStack *gsignalStack) bool {
+	sp := uintptr(unsafe.Pointer(&sig))
+	if sp >= mp.gsignal.stack.lo && sp < mp.gsignal.stack.hi {
+		return false
+	}
+
+	var st stackt
+	sigaltstack(nil, &st)
+	stsp := uintptr(unsafe.Pointer(st.ss_sp))
+	if st.ss_flags&_SS_DISABLE == 0 && sp >= stsp && sp < stsp+st.ss_size {
+		setGsignalStack(&st, gsigStack)
+		return true
+	}
+
+	if sp >= mp.g0.stack.lo && sp < mp.g0.stack.hi {
+		// The signal was delivered on the g0 stack.
+		// This can happen when linked with C code
+		// using the thread sanitizer, which collects
+		// signals then delivers them itself by calling
+		// the signal handler directly when C code,
+		// including C code called via cgo, calls a
+		// TSAN-intercepted function such as malloc.
+		//
+		// We check this condition last as g0.stack.lo
+		// may be not very accurate (see mstart).
+		st := stackt{ss_size: mp.g0.stack.hi - mp.g0.stack.lo}
+		setSignalstackSP(&st, mp.g0.stack.lo)
+		setGsignalStack(&st, gsigStack)
+		return true
+	}
+
+	// sp is not within gsignal stack, g0 stack, or sigaltstack. Bad.
+	setg(nil)
+	needm()
+	if st.ss_flags&_SS_DISABLE != 0 {
+		noSignalStack(sig)
+	} else {
+		sigNotOnStack(sig)
+	}
+	dropm()
+	return false
+}
+
+// crashing is the number of m's we have waited for when implementing
+// GOTRACEBACK=crash when a signal is received.
+var crashing int32
+
+// testSigtrap and testSigusr1 are used by the runtime tests. If
+// non-nil, it is called on SIGTRAP/SIGUSR1. If it returns true, the
+// normal behavior on this signal is suppressed.
+var testSigtrap func(info *siginfo, ctxt *sigctxt, gp *g) bool
+var testSigusr1 func(gp *g) bool
+
+// sighandler is invoked when a signal occurs. The global g will be
+// set to a gsignal goroutine and we will be running on the alternate
+// signal stack. The parameter g will be the value of the global g
+// when the signal occurred. The sig, info, and ctxt parameters are
+// from the system signal handler: they are the parameters passed when
+// the SA is passed to the sigaction system call.
+//
+// The garbage collector may have stopped the world, so write barriers
+// are not allowed.
+//
+//go:nowritebarrierrec
+func sighandler(sig uint32, info *siginfo, ctxt unsafe.Pointer, gp *g) {
+	_g_ := getg()
+	c := &sigctxt{info, ctxt}
+	mp := _g_.m
+
+	// Cgo TSAN (not the Go race detector) intercepts signals and calls the
+	// signal handler at a later time. When the signal handler is called, the
+	// memory may have changed, but the signal context remains old. The
+	// unmatched signal context and memory makes it unsafe to unwind or inspect
+	// the stack. So we ignore delayed non-fatal signals that will cause a stack
+	// inspection (profiling signal and preemption signal).
+	// cgo_yield is only non-nil for TSAN, and is specifically used to trigger
+	// signal delivery. We use that as an indicator of delayed signals.
+	// For delayed signals, the handler is called on the g0 stack (see
+	// adjustSignalStack).
+	delayedSignal := *cgo_yield != nil && mp != nil && _g_.stack == mp.g0.stack
+
+	if sig == _SIGPROF {
+		// Some platforms (Linux) have per-thread timers, which we use in
+		// combination with the process-wide timer. Avoid double-counting.
+		if !delayedSignal && validSIGPROF(mp, c) {
+			sigprof(c.sigpc(), c.sigsp(), c.siglr(), gp, mp)
+		}
+		return
+	}
+
+	if sig == _SIGTRAP && testSigtrap != nil && testSigtrap(info, (*sigctxt)(noescape(unsafe.Pointer(c))), gp) {
+		return
+	}
+
+	if sig == _SIGUSR1 && testSigusr1 != nil && testSigusr1(gp) {
+		return
+	}
+
+	if (GOOS == "linux" || GOOS == "android") && sig == sigPerThreadSyscall {
+		// sigPerThreadSyscall is the same signal used by glibc for
+		// per-thread syscalls on Linux. We use it for the same purpose
+		// in non-cgo binaries. Since this signal is not _SigNotify,
+		// there is nothing more to do once we run the syscall.
+		runPerThreadSyscall()
+		return
+	}
+
+	if sig == sigPreempt && debug.asyncpreemptoff == 0 && !delayedSignal {
+		// Might be a preemption signal.
+		doSigPreempt(gp, c)
+		// Even if this was definitely a preemption signal, it
+		// may have been coalesced with another signal, so we
+		// still let it through to the application.
+	}
+
+	flags := int32(_SigThrow)
+	if sig < uint32(len(sigtable)) {
+		flags = sigtable[sig].flags
+	}
+	if c.sigcode() != _SI_USER && flags&_SigPanic != 0 && gp.throwsplit {
+		// We can't safely sigpanic because it may grow the
+		// stack. Abort in the signal handler instead.
+		flags = _SigThrow
+	}
+	if isAbortPC(c.sigpc()) {
+		// On many architectures, the abort function just
+		// causes a memory fault. Don't turn that into a panic.
+		flags = _SigThrow
+	}
+	if c.sigcode() != _SI_USER && flags&_SigPanic != 0 {
+		// The signal is going to cause a panic.
+		// Arrange the stack so that it looks like the point
+		// where the signal occurred made a call to the
+		// function sigpanic. Then set the PC to sigpanic.
+
+		// Have to pass arguments out of band since
+		// augmenting the stack frame would break
+		// the unwinding code.
+		gp.sig = sig
+		gp.sigcode0 = uintptr(c.sigcode())
+		gp.sigcode1 = uintptr(c.fault())
+		gp.sigpc = c.sigpc()
+
+		c.preparePanic(sig, gp)
+		return
+	}
+
+	if c.sigcode() == _SI_USER || flags&_SigNotify != 0 {
+		if sigsend(sig) {
+			return
+		}
+	}
+
+	if c.sigcode() == _SI_USER && signal_ignored(sig) {
+		return
+	}
+
+	if flags&_SigKill != 0 {
+		dieFromSignal(sig)
+	}
+
+	// _SigThrow means that we should exit now.
+	// If we get here with _SigPanic, it means that the signal
+	// was sent to us by a program (c.sigcode() == _SI_USER);
+	// in that case, if we didn't handle it in sigsend, we exit now.
+	if flags&(_SigThrow|_SigPanic) == 0 {
+		return
+	}
+
+	_g_.m.throwing = throwTypeRuntime
+	_g_.m.caughtsig.set(gp)
+
+	if crashing == 0 {
+		startpanic_m()
+	}
+
+	if sig < uint32(len(sigtable)) {
+		print(sigtable[sig].name, "\n")
+	} else {
+		print("Signal ", sig, "\n")
+	}
+
+	print("PC=", hex(c.sigpc()), " m=", _g_.m.id, " sigcode=", c.sigcode(), "\n")
+	if _g_.m.incgo && gp == _g_.m.g0 && _g_.m.curg != nil {
+		print("signal arrived during cgo execution\n")
+		// Switch to curg so that we get a traceback of the Go code
+		// leading up to the cgocall, which switched from curg to g0.
+		gp = _g_.m.curg
+	}
+	if sig == _SIGILL || sig == _SIGFPE {
+		// It would be nice to know how long the instruction is.
+		// Unfortunately, that's complicated to do in general (mostly for x86
+		// and s930x, but other archs have non-standard instruction lengths also).
+		// Opt to print 16 bytes, which covers most instructions.
+		const maxN = 16
+		n := uintptr(maxN)
+		// We have to be careful, though. If we're near the end of
+		// a page and the following page isn't mapped, we could
+		// segfault. So make sure we don't straddle a page (even though
+		// that could lead to printing an incomplete instruction).
+		// We're assuming here we can read at least the page containing the PC.
+		// I suppose it is possible that the page is mapped executable but not readable?
+		pc := c.sigpc()
+		if n > physPageSize-pc%physPageSize {
+			n = physPageSize - pc%physPageSize
+		}
+		print("instruction bytes:")
+		b := (*[maxN]byte)(unsafe.Pointer(pc))
+		for i := uintptr(0); i < n; i++ {
+			print(" ", hex(b[i]))
+		}
+		println()
+	}
+	print("\n")
+
+	level, _, docrash := gotraceback()
+	if level > 0 {
+		goroutineheader(gp)
+		tracebacktrap(c.sigpc(), c.sigsp(), c.siglr(), gp)
+		if crashing > 0 && gp != _g_.m.curg && _g_.m.curg != nil && readgstatus(_g_.m.curg)&^_Gscan == _Grunning {
+			// tracebackothers on original m skipped this one; trace it now.
+			goroutineheader(_g_.m.curg)
+			traceback(^uintptr(0), ^uintptr(0), 0, _g_.m.curg)
+		} else if crashing == 0 {
+			tracebackothers(gp)
+			print("\n")
+		}
+		dumpregs(c)
+	}
+
+	if docrash {
+		crashing++
+		if crashing < mcount()-int32(extraMCount) {
+			// There are other m's that need to dump their stacks.
+			// Relay SIGQUIT to the next m by sending it to the current process.
+			// All m's that have already received SIGQUIT have signal masks blocking
+			// receipt of any signals, so the SIGQUIT will go to an m that hasn't seen it yet.
+			// When the last m receives the SIGQUIT, it will fall through to the call to
+			// crash below. Just in case the relaying gets botched, each m involved in
+			// the relay sleeps for 5 seconds and then does the crash/exit itself.
+			// In expected operation, the last m has received the SIGQUIT and run
+			// crash/exit and the process is gone, all long before any of the
+			// 5-second sleeps have finished.
+			print("\n-----\n\n")
+			raiseproc(_SIGQUIT)
+			usleep(5 * 1000 * 1000)
+		}
+		crash()
+	}
+
+	printDebugLog()
+
+	exit(2)
+}
+
+// sigpanic turns a synchronous signal into a run-time panic.
+// If the signal handler sees a synchronous panic, it arranges the
+// stack to look like the function where the signal occurred called
+// sigpanic, sets the signal's PC value to sigpanic, and returns from
+// the signal handler. The effect is that the program will act as
+// though the function that got the signal simply called sigpanic
+// instead.
+//
+// This must NOT be nosplit because the linker doesn't know where
+// sigpanic calls can be injected.
+//
+// The signal handler must not inject a call to sigpanic if
+// getg().throwsplit, since sigpanic may need to grow the stack.
+//
+// This is exported via linkname to assembly in runtime/cgo.
+//
+//go:linkname sigpanic
+func sigpanic() {
+	g := getg()
+	if !canpanic(g) {
+		throw("unexpected signal during runtime execution")
+	}
+
+	switch g.sig {
+	case _SIGBUS:
+		if g.sigcode0 == _BUS_ADRERR && g.sigcode1 < 0x1000 {
+			panicmem()
+		}
+		// Support runtime/debug.SetPanicOnFault.
+		if g.paniconfault {
+			panicmemAddr(g.sigcode1)
+		}
+		print("unexpected fault address ", hex(g.sigcode1), "\n")
+		throw("fault")
+	case _SIGSEGV:
+		if (g.sigcode0 == 0 || g.sigcode0 == _SEGV_MAPERR || g.sigcode0 == _SEGV_ACCERR) && g.sigcode1 < 0x1000 {
+			panicmem()
+		}
+		// Support runtime/debug.SetPanicOnFault.
+		if g.paniconfault {
+			panicmemAddr(g.sigcode1)
+		}
+		print("unexpected fault address ", hex(g.sigcode1), "\n")
+		throw("fault")
+	case _SIGFPE:
+		switch g.sigcode0 {
+		case _FPE_INTDIV:
+			panicdivide()
+		case _FPE_INTOVF:
+			panicoverflow()
+		}
+		panicfloat()
+	}
+
+	if g.sig >= uint32(len(sigtable)) {
+		// can't happen: we looked up g.sig in sigtable to decide to call sigpanic
+		throw("unexpected signal value")
+	}
+	panic(errorString(sigtable[g.sig].name))
+}
+
+// dieFromSignal kills the program with a signal.
+// This provides the expected exit status for the shell.
+// This is only called with fatal signals expected to kill the process.
+//
+//go:nosplit
+//go:nowritebarrierrec
+func dieFromSignal(sig uint32) {
+	unblocksig(sig)
+	// Mark the signal as unhandled to ensure it is forwarded.
+	atomic.Store(&handlingSig[sig], 0)
+	raise(sig)
+
+	// That should have killed us. On some systems, though, raise
+	// sends the signal to the whole process rather than to just
+	// the current thread, which means that the signal may not yet
+	// have been delivered. Give other threads a chance to run and
+	// pick up the signal.
+	osyield()
+	osyield()
+	osyield()
+
+	// If that didn't work, try _SIG_DFL.
+	setsig(sig, _SIG_DFL)
+	raise(sig)
+
+	osyield()
+	osyield()
+	osyield()
+
+	// If we are still somehow running, just exit with the wrong status.
+	exit(2)
+}
+
+// raisebadsignal is called when a signal is received on a non-Go
+// thread, and the Go program does not want to handle it (that is, the
+// program has not called os/signal.Notify for the signal).
+func raisebadsignal(sig uint32, c *sigctxt) {
+	if sig == _SIGPROF {
+		// Ignore profiling signals that arrive on non-Go threads.
+		return
+	}
+
+	var handler uintptr
+	if sig >= _NSIG {
+		handler = _SIG_DFL
+	} else {
+		handler = atomic.Loaduintptr(&fwdSig[sig])
+	}
+
+	// Reset the signal handler and raise the signal.
+	// We are currently running inside a signal handler, so the
+	// signal is blocked. We need to unblock it before raising the
+	// signal, or the signal we raise will be ignored until we return
+	// from the signal handler. We know that the signal was unblocked
+	// before entering the handler, or else we would not have received
+	// it. That means that we don't have to worry about blocking it
+	// again.
+	unblocksig(sig)
+	setsig(sig, handler)
+
+	// If we're linked into a non-Go program we want to try to
+	// avoid modifying the original context in which the signal
+	// was raised. If the handler is the default, we know it
+	// is non-recoverable, so we don't have to worry about
+	// re-installing sighandler. At this point we can just
+	// return and the signal will be re-raised and caught by
+	// the default handler with the correct context.
+	//
+	// On FreeBSD, the libthr sigaction code prevents
+	// this from working so we fall through to raise.
+	if GOOS != "freebsd" && (isarchive || islibrary) && handler == _SIG_DFL && c.sigcode() != _SI_USER {
+		return
+	}
+
+	raise(sig)
+
+	// Give the signal a chance to be delivered.
+	// In almost all real cases the program is about to crash,
+	// so sleeping here is not a waste of time.
+	usleep(1000)
+
+	// If the signal didn't cause the program to exit, restore the
+	// Go signal handler and carry on.
+	//
+	// We may receive another instance of the signal before we
+	// restore the Go handler, but that is not so bad: we know
+	// that the Go program has been ignoring the signal.
+	setsig(sig, abi.FuncPCABIInternal(sighandler))
+}
+
+//go:nosplit
+func crash() {
+	// OS X core dumps are linear dumps of the mapped memory,
+	// from the first virtual byte to the last, with zeros in the gaps.
+	// Because of the way we arrange the address space on 64-bit systems,
+	// this means the OS X core file will be >128 GB and even on a zippy
+	// workstation can take OS X well over an hour to write (uninterruptible).
+	// Save users from making that mistake.
+	if GOOS == "darwin" && GOARCH == "amd64" {
+		return
+	}
+
+	dieFromSignal(_SIGABRT)
+}
+
+// ensureSigM starts one global, sleeping thread to make sure at least one thread
+// is available to catch signals enabled for os/signal.
+func ensureSigM() {
+	if maskUpdatedChan != nil {
+		return
+	}
+	maskUpdatedChan = make(chan struct{})
+	disableSigChan = make(chan uint32)
+	enableSigChan = make(chan uint32)
+	go func() {
+		// Signal masks are per-thread, so make sure this goroutine stays on one
+		// thread.
+		LockOSThread()
+		defer UnlockOSThread()
+		// The sigBlocked mask contains the signals not active for os/signal,
+		// initially all signals except the essential. When signal.Notify()/Stop is called,
+		// sigenable/sigdisable in turn notify this thread to update its signal
+		// mask accordingly.
+		sigBlocked := sigset_all
+		for i := range sigtable {
+			if !blockableSig(uint32(i)) {
+				sigdelset(&sigBlocked, i)
+			}
+		}
+		sigprocmask(_SIG_SETMASK, &sigBlocked, nil)
+		for {
+			select {
+			case sig := <-enableSigChan:
+				if sig > 0 {
+					sigdelset(&sigBlocked, int(sig))
+				}
+			case sig := <-disableSigChan:
+				if sig > 0 && blockableSig(sig) {
+					sigaddset(&sigBlocked, int(sig))
+				}
+			}
+			sigprocmask(_SIG_SETMASK, &sigBlocked, nil)
+			maskUpdatedChan <- struct{}{}
+		}
+	}()
+}
+
+// This is called when we receive a signal when there is no signal stack.
+// This can only happen if non-Go code calls sigaltstack to disable the
+// signal stack.
+func noSignalStack(sig uint32) {
+	println("signal", sig, "received on thread with no signal stack")
+	throw("non-Go code disabled sigaltstack")
+}
+
+// This is called if we receive a signal when there is a signal stack
+// but we are not on it. This can only happen if non-Go code called
+// sigaction without setting the SS_ONSTACK flag.
+func sigNotOnStack(sig uint32) {
+	println("signal", sig, "received but handler not on signal stack")
+	throw("non-Go code set up signal handler without SA_ONSTACK flag")
+}
+
+// signalDuringFork is called if we receive a signal while doing a fork.
+// We do not want signals at that time, as a signal sent to the process
+// group may be delivered to the child process, causing confusion.
+// This should never be called, because we block signals across the fork;
+// this function is just a safety check. See issue 18600 for background.
+func signalDuringFork(sig uint32) {
+	println("signal", sig, "received during fork")
+	throw("signal received during fork")
+}
+
+var badginsignalMsg = "fatal: bad g in signal handler\n"
+
+// This runs on a foreign stack, without an m or a g. No stack split.
+//
+//go:nosplit
+//go:norace
+//go:nowritebarrierrec
+func badsignal(sig uintptr, c *sigctxt) {
+	if !iscgo && !cgoHasExtraM {
+		// There is no extra M. needm will not be able to grab
+		// an M. Instead of hanging, just crash.
+		// Cannot call split-stack function as there is no G.
+		s := stringStructOf(&badginsignalMsg)
+		write(2, s.str, int32(s.len))
+		exit(2)
+		*(*uintptr)(unsafe.Pointer(uintptr(123))) = 2
+	}
+	needm()
+	if !sigsend(uint32(sig)) {
+		// A foreign thread received the signal sig, and the
+		// Go code does not want to handle it.
+		raisebadsignal(uint32(sig), c)
+	}
+	dropm()
+}
+
+//go:noescape
+func sigfwd(fn uintptr, sig uint32, info *siginfo, ctx unsafe.Pointer)
+
+// Determines if the signal should be handled by Go and if not, forwards the
+// signal to the handler that was installed before Go's. Returns whether the
+// signal was forwarded.
+// This is called by the signal handler, and the world may be stopped.
+//
+//go:nosplit
+//go:nowritebarrierrec
+func sigfwdgo(sig uint32, info *siginfo, ctx unsafe.Pointer) bool {
+	if sig >= uint32(len(sigtable)) {
+		return false
+	}
+	fwdFn := atomic.Loaduintptr(&fwdSig[sig])
+	flags := sigtable[sig].flags
+
+	// If we aren't handling the signal, forward it.
+	if atomic.Load(&handlingSig[sig]) == 0 || !signalsOK {
+		// If the signal is ignored, doing nothing is the same as forwarding.
+		if fwdFn == _SIG_IGN || (fwdFn == _SIG_DFL && flags&_SigIgn != 0) {
+			return true
+		}
+		// We are not handling the signal and there is no other handler to forward to.
+		// Crash with the default behavior.
+		if fwdFn == _SIG_DFL {
+			setsig(sig, _SIG_DFL)
+			dieFromSignal(sig)
+			return false
+		}
+
+		sigfwd(fwdFn, sig, info, ctx)
+		return true
+	}
+
+	// This function and its caller sigtrampgo assumes SIGPIPE is delivered on the
+	// originating thread. This property does not hold on macOS (golang.org/issue/33384),
+	// so we have no choice but to ignore SIGPIPE.
+	if (GOOS == "darwin" || GOOS == "ios") && sig == _SIGPIPE {
+		return true
+	}
+
+	// If there is no handler to forward to, no need to forward.
+	if fwdFn == _SIG_DFL {
+		return false
+	}
+
+	c := &sigctxt{info, ctx}
+	// Only forward synchronous signals and SIGPIPE.
+	// Unfortunately, user generated SIGPIPEs will also be forwarded, because si_code
+	// is set to _SI_USER even for a SIGPIPE raised from a write to a closed socket
+	// or pipe.
+	if (c.sigcode() == _SI_USER || flags&_SigPanic == 0) && sig != _SIGPIPE {
+		return false
+	}
+	// Determine if the signal occurred inside Go code. We test that:
+	//   (1) we weren't in VDSO page,
+	//   (2) we were in a goroutine (i.e., m.curg != nil), and
+	//   (3) we weren't in CGO.
+	g := sigFetchG(c)
+	if g != nil && g.m != nil && g.m.curg != nil && !g.m.incgo {
+		return false
+	}
+
+	// Signal not handled by Go, forward it.
+	if fwdFn != _SIG_IGN {
+		sigfwd(fwdFn, sig, info, ctx)
+	}
+
+	return true
+}
+
+// sigsave saves the current thread's signal mask into *p.
+// This is used to preserve the non-Go signal mask when a non-Go
+// thread calls a Go function.
+// This is nosplit and nowritebarrierrec because it is called by needm
+// which may be called on a non-Go thread with no g available.
+//
+//go:nosplit
+//go:nowritebarrierrec
+func sigsave(p *sigset) {
+	sigprocmask(_SIG_SETMASK, nil, p)
+}
+
+// msigrestore sets the current thread's signal mask to sigmask.
+// This is used to restore the non-Go signal mask when a non-Go thread
+// calls a Go function.
+// This is nosplit and nowritebarrierrec because it is called by dropm
+// after g has been cleared.
+//
+//go:nosplit
+//go:nowritebarrierrec
+func msigrestore(sigmask sigset) {
+	sigprocmask(_SIG_SETMASK, &sigmask, nil)
+}
+
+// sigsetAllExiting is used by sigblock(true) when a thread is
+// exiting. sigset_all is defined in OS specific code, and per GOOS
+// behavior may override this default for sigsetAllExiting: see
+// osinit().
+var sigsetAllExiting = sigset_all
+
+// sigblock blocks signals in the current thread's signal mask.
+// This is used to block signals while setting up and tearing down g
+// when a non-Go thread calls a Go function. When a thread is exiting
+// we use the sigsetAllExiting value, otherwise the OS specific
+// definition of sigset_all is used.
+// This is nosplit and nowritebarrierrec because it is called by needm
+// which may be called on a non-Go thread with no g available.
+//
+//go:nosplit
+//go:nowritebarrierrec
+func sigblock(exiting bool) {
+	if exiting {
+		sigprocmask(_SIG_SETMASK, &sigsetAllExiting, nil)
+		return
+	}
+	sigprocmask(_SIG_SETMASK, &sigset_all, nil)
+}
+
+// unblocksig removes sig from the current thread's signal mask.
+// This is nosplit and nowritebarrierrec because it is called from
+// dieFromSignal, which can be called by sigfwdgo while running in the
+// signal handler, on the signal stack, with no g available.
+//
+//go:nosplit
+//go:nowritebarrierrec
+func unblocksig(sig uint32) {
+	var set sigset
+	sigaddset(&set, int(sig))
+	sigprocmask(_SIG_UNBLOCK, &set, nil)
+}
+
+// minitSignals is called when initializing a new m to set the
+// thread's alternate signal stack and signal mask.
+func minitSignals() {
+	minitSignalStack()
+	minitSignalMask()
+}
+
+// minitSignalStack is called when initializing a new m to set the
+// alternate signal stack. If the alternate signal stack is not set
+// for the thread (the normal case) then set the alternate signal
+// stack to the gsignal stack. If the alternate signal stack is set
+// for the thread (the case when a non-Go thread sets the alternate
+// signal stack and then calls a Go function) then set the gsignal
+// stack to the alternate signal stack. We also set the alternate
+// signal stack to the gsignal stack if cgo is not used (regardless
+// of whether it is already set). Record which choice was made in
+// newSigstack, so that it can be undone in unminit.
+func minitSignalStack() {
+	_g_ := getg()
+	var st stackt
+	sigaltstack(nil, &st)
+	if st.ss_flags&_SS_DISABLE != 0 || !iscgo {
+		signalstack(&_g_.m.gsignal.stack)
+		_g_.m.newSigstack = true
+	} else {
+		setGsignalStack(&st, &_g_.m.goSigStack)
+		_g_.m.newSigstack = false
+	}
+}
+
+// minitSignalMask is called when initializing a new m to set the
+// thread's signal mask. When this is called all signals have been
+// blocked for the thread.  This starts with m.sigmask, which was set
+// either from initSigmask for a newly created thread or by calling
+// sigsave if this is a non-Go thread calling a Go function. It
+// removes all essential signals from the mask, thus causing those
+// signals to not be blocked. Then it sets the thread's signal mask.
+// After this is called the thread can receive signals.
+func minitSignalMask() {
+	nmask := getg().m.sigmask
+	for i := range sigtable {
+		if !blockableSig(uint32(i)) {
+			sigdelset(&nmask, i)
+		}
+	}
+	sigprocmask(_SIG_SETMASK, &nmask, nil)
+}
+
+// unminitSignals is called from dropm, via unminit, to undo the
+// effect of calling minit on a non-Go thread.
+//
+//go:nosplit
+func unminitSignals() {
+	if getg().m.newSigstack {
+		st := stackt{ss_flags: _SS_DISABLE}
+		sigaltstack(&st, nil)
+	} else {
+		// We got the signal stack from someone else. Restore
+		// the Go-allocated stack in case this M gets reused
+		// for another thread (e.g., it's an extram). Also, on
+		// Android, libc allocates a signal stack for all
+		// threads, so it's important to restore the Go stack
+		// even on Go-created threads so we can free it.
+		restoreGsignalStack(&getg().m.goSigStack)
+	}
+}
+
+// blockableSig reports whether sig may be blocked by the signal mask.
+// We never want to block the signals marked _SigUnblock;
+// these are the synchronous signals that turn into a Go panic.
+// We never want to block the preemption signal if it is being used.
+// In a Go program--not a c-archive/c-shared--we never want to block
+// the signals marked _SigKill or _SigThrow, as otherwise it's possible
+// for all running threads to block them and delay their delivery until
+// we start a new thread. When linked into a C program we let the C code
+// decide on the disposition of those signals.
+func blockableSig(sig uint32) bool {
+	flags := sigtable[sig].flags
+	if flags&_SigUnblock != 0 {
+		return false
+	}
+	if sig == sigPreempt && preemptMSupported && debug.asyncpreemptoff == 0 {
+		return false
+	}
+	if isarchive || islibrary {
+		return true
+	}
+	return flags&(_SigKill|_SigThrow) == 0
+}
+
+// gsignalStack saves the fields of the gsignal stack changed by
+// setGsignalStack.
+type gsignalStack struct {
+	stack       stack
+	stackguard0 uintptr
+	stackguard1 uintptr
+	stktopsp    uintptr
+}
+
+// setGsignalStack sets the gsignal stack of the current m to an
+// alternate signal stack returned from the sigaltstack system call.
+// It saves the old values in *old for use by restoreGsignalStack.
+// This is used when handling a signal if non-Go code has set the
+// alternate signal stack.
+//
+//go:nosplit
+//go:nowritebarrierrec
+func setGsignalStack(st *stackt, old *gsignalStack) {
+	g := getg()
+	if old != nil {
+		old.stack = g.m.gsignal.stack
+		old.stackguard0 = g.m.gsignal.stackguard0
+		old.stackguard1 = g.m.gsignal.stackguard1
+		old.stktopsp = g.m.gsignal.stktopsp
+	}
+	stsp := uintptr(unsafe.Pointer(st.ss_sp))
+	g.m.gsignal.stack.lo = stsp
+	g.m.gsignal.stack.hi = stsp + st.ss_size
+	g.m.gsignal.stackguard0 = stsp + _StackGuard
+	g.m.gsignal.stackguard1 = stsp + _StackGuard
+}
+
+// restoreGsignalStack restores the gsignal stack to the value it had
+// before entering the signal handler.
+//
+//go:nosplit
+//go:nowritebarrierrec
+func restoreGsignalStack(st *gsignalStack) {
+	gp := getg().m.gsignal
+	gp.stack = st.stack
+	gp.stackguard0 = st.stackguard0
+	gp.stackguard1 = st.stackguard1
+	gp.stktopsp = st.stktopsp
+}
+
+// signalstack sets the current thread's alternate signal stack to s.
+//
+//go:nosplit
+func signalstack(s *stack) {
+	st := stackt{ss_size: s.hi - s.lo}
+	setSignalstackSP(&st, s.lo)
+	sigaltstack(&st, nil)
+}
+
+// setsigsegv is used on darwin/arm64 to fake a segmentation fault.
+//
+// This is exported via linkname to assembly in runtime/cgo.
+//
+//go:nosplit
+//go:linkname setsigsegv
+func setsigsegv(pc uintptr) {
+	g := getg()
+	g.sig = _SIGSEGV
+	g.sigpc = pc
+	g.sigcode0 = _SEGV_MAPERR
+	g.sigcode1 = 0 // TODO: emulate si_addr
+}
diff --git a/contrib/go/_std_1.19/src/runtime/sigqueue.go b/contrib/go/_std_1.19/src/runtime/sigqueue.go
new file mode 100644
index 0000000000..49502cbed3
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/sigqueue.go
@@ -0,0 +1,275 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements runtime support for signal handling.
+//
+// Most synchronization primitives are not available from
+// the signal handler (it cannot block, allocate memory, or use locks)
+// so the handler communicates with a processing goroutine
+// via struct sig, below.
+//
+// sigsend is called by the signal handler to queue a new signal.
+// signal_recv is called by the Go program to receive a newly queued signal.
+//
+// Synchronization between sigsend and signal_recv is based on the sig.state
+// variable. It can be in three states:
+// * sigReceiving means that signal_recv is blocked on sig.Note and there are
+//   no new pending signals.
+// * sigSending means that sig.mask *may* contain new pending signals,
+//   signal_recv can't be blocked in this state.
+// * sigIdle means that there are no new pending signals and signal_recv is not
+//   blocked.
+//
+// Transitions between states are done atomically with CAS.
+//
+// When signal_recv is unblocked, it resets sig.Note and rechecks sig.mask.
+// If several sigsends and signal_recv execute concurrently, it can lead to
+// unnecessary rechecks of sig.mask, but it cannot lead to missed signals
+// nor deadlocks.
+
+//go:build !plan9
+
+package runtime
+
+import (
+	"runtime/internal/atomic"
+	_ "unsafe" // for go:linkname
+)
+
+// sig handles communication between the signal handler and os/signal.
+// Other than the inuse and recv fields, the fields are accessed atomically.
+//
+// The wanted and ignored fields are only written by one goroutine at
+// a time; access is controlled by the handlers Mutex in os/signal.
+// The fields are only read by that one goroutine and by the signal handler.
+// We access them atomically to minimize the race between setting them
+// in the goroutine calling os/signal and the signal handler,
+// which may be running in a different thread. That race is unavoidable,
+// as there is no connection between handling a signal and receiving one,
+// but atomic instructions should minimize it.
+var sig struct {
+	note       note
+	mask       [(_NSIG + 31) / 32]uint32
+	wanted     [(_NSIG + 31) / 32]uint32
+	ignored    [(_NSIG + 31) / 32]uint32
+	recv       [(_NSIG + 31) / 32]uint32
+	state      uint32
+	delivering uint32
+	inuse      bool
+}
+
+const (
+	sigIdle = iota
+	sigReceiving
+	sigSending
+)
+
+// sigsend delivers a signal from sighandler to the internal signal delivery queue.
+// It reports whether the signal was sent. If not, the caller typically crashes the program.
+// It runs from the signal handler, so it's limited in what it can do.
+func sigsend(s uint32) bool {
+	bit := uint32(1) << uint(s&31)
+	if s >= uint32(32*len(sig.wanted)) {
+		return false
+	}
+
+	atomic.Xadd(&sig.delivering, 1)
+	// We are running in the signal handler; defer is not available.
+
+	if w := atomic.Load(&sig.wanted[s/32]); w&bit == 0 {
+		atomic.Xadd(&sig.delivering, -1)
+		return false
+	}
+
+	// Add signal to outgoing queue.
+	for {
+		mask := sig.mask[s/32]
+		if mask&bit != 0 {
+			atomic.Xadd(&sig.delivering, -1)
+			return true // signal already in queue
+		}
+		if atomic.Cas(&sig.mask[s/32], mask, mask|bit) {
+			break
+		}
+	}
+
+	// Notify receiver that queue has new bit.
+Send:
+	for {
+		switch atomic.Load(&sig.state) {
+		default:
+			throw("sigsend: inconsistent state")
+		case sigIdle:
+			if atomic.Cas(&sig.state, sigIdle, sigSending) {
+				break Send
+			}
+		case sigSending:
+			// notification already pending
+			break Send
+		case sigReceiving:
+			if atomic.Cas(&sig.state, sigReceiving, sigIdle) {
+				if GOOS == "darwin" || GOOS == "ios" {
+					sigNoteWakeup(&sig.note)
+					break Send
+				}
+				notewakeup(&sig.note)
+				break Send
+			}
+		}
+	}
+
+	atomic.Xadd(&sig.delivering, -1)
+	return true
+}
+
+// Called to receive the next queued signal.
+// Must only be called from a single goroutine at a time.
+//
+//go:linkname signal_recv os/signal.signal_recv
+func signal_recv() uint32 {
+	for {
+		// Serve any signals from local copy.
+		for i := uint32(0); i < _NSIG; i++ {
+			if sig.recv[i/32]&(1<<(i&31)) != 0 {
+				sig.recv[i/32] &^= 1 << (i & 31)
+				return i
+			}
+		}
+
+		// Wait for updates to be available from signal sender.
+	Receive:
+		for {
+			switch atomic.Load(&sig.state) {
+			default:
+				throw("signal_recv: inconsistent state")
+			case sigIdle:
+				if atomic.Cas(&sig.state, sigIdle, sigReceiving) {
+					if GOOS == "darwin" || GOOS == "ios" {
+						sigNoteSleep(&sig.note)
+						break Receive
+					}
+					notetsleepg(&sig.note, -1)
+					noteclear(&sig.note)
+					break Receive
+				}
+			case sigSending:
+				if atomic.Cas(&sig.state, sigSending, sigIdle) {
+					break Receive
+				}
+			}
+		}
+
+		// Incorporate updates from sender into local copy.
+		for i := range sig.mask {
+			sig.recv[i] = atomic.Xchg(&sig.mask[i], 0)
+		}
+	}
+}
+
+// signalWaitUntilIdle waits until the signal delivery mechanism is idle.
+// This is used to ensure that we do not drop a signal notification due
+// to a race between disabling a signal and receiving a signal.
+// This assumes that signal delivery has already been disabled for
+// the signal(s) in question, and here we are just waiting to make sure
+// that all the signals have been delivered to the user channels
+// by the os/signal package.
+//
+//go:linkname signalWaitUntilIdle os/signal.signalWaitUntilIdle
+func signalWaitUntilIdle() {
+	// Although the signals we care about have been removed from
+	// sig.wanted, it is possible that another thread has received
+	// a signal, has read from sig.wanted, is now updating sig.mask,
+	// and has not yet woken up the processor thread. We need to wait
+	// until all current signal deliveries have completed.
+	for atomic.Load(&sig.delivering) != 0 {
+		Gosched()
+	}
+
+	// Although WaitUntilIdle seems like the right name for this
+	// function, the state we are looking for is sigReceiving, not
+	// sigIdle.  The sigIdle state is really more like sigProcessing.
+	for atomic.Load(&sig.state) != sigReceiving {
+		Gosched()
+	}
+}
+
+// Must only be called from a single goroutine at a time.
+//
+//go:linkname signal_enable os/signal.signal_enable
+func signal_enable(s uint32) {
+	if !sig.inuse {
+		// This is the first call to signal_enable. Initialize.
+		sig.inuse = true // enable reception of signals; cannot disable
+		if GOOS == "darwin" || GOOS == "ios" {
+			sigNoteSetup(&sig.note)
+		} else {
+			noteclear(&sig.note)
+		}
+	}
+
+	if s >= uint32(len(sig.wanted)*32) {
+		return
+	}
+
+	w := sig.wanted[s/32]
+	w |= 1 << (s & 31)
+	atomic.Store(&sig.wanted[s/32], w)
+
+	i := sig.ignored[s/32]
+	i &^= 1 << (s & 31)
+	atomic.Store(&sig.ignored[s/32], i)
+
+	sigenable(s)
+}
+
+// Must only be called from a single goroutine at a time.
+//
+//go:linkname signal_disable os/signal.signal_disable
+func signal_disable(s uint32) {
+	if s >= uint32(len(sig.wanted)*32) {
+		return
+	}
+	sigdisable(s)
+
+	w := sig.wanted[s/32]
+	w &^= 1 << (s & 31)
+	atomic.Store(&sig.wanted[s/32], w)
+}
+
+// Must only be called from a single goroutine at a time.
+//
+//go:linkname signal_ignore os/signal.signal_ignore
+func signal_ignore(s uint32) {
+	if s >= uint32(len(sig.wanted)*32) {
+		return
+	}
+	sigignore(s)
+
+	w := sig.wanted[s/32]
+	w &^= 1 << (s & 31)
+	atomic.Store(&sig.wanted[s/32], w)
+
+	i := sig.ignored[s/32]
+	i |= 1 << (s & 31)
+	atomic.Store(&sig.ignored[s/32], i)
+}
+
+// sigInitIgnored marks the signal as already ignored. This is called at
+// program start by initsig. In a shared library initsig is called by
+// libpreinit, so the runtime may not be initialized yet.
+//
+//go:nosplit
+func sigInitIgnored(s uint32) {
+	i := sig.ignored[s/32]
+	i |= 1 << (s & 31)
+	atomic.Store(&sig.ignored[s/32], i)
+}
+
+// Checked by signal handlers.
+//
+//go:linkname signal_ignored os/signal.signal_ignored
+func signal_ignored(s uint32) bool {
+	i := atomic.Load(&sig.ignored[s/32])
+	return i&(1<<(s&31)) != 0
+}
diff --git a/contrib/go/_std_1.18/src/runtime/sigqueue_note.go b/contrib/go/_std_1.19/src/runtime/sigqueue_note.go
index fb1a517fa5..fb1a517fa5 100644
--- a/contrib/go/_std_1.18/src/runtime/sigqueue_note.go
+++ b/contrib/go/_std_1.19/src/runtime/sigqueue_note.go
diff --git a/contrib/go/_std_1.18/src/runtime/sigtab_linux_generic.go b/contrib/go/_std_1.19/src/runtime/sigtab_linux_generic.go
index fe93bbafb5..fe93bbafb5 100644
--- a/contrib/go/_std_1.18/src/runtime/sigtab_linux_generic.go
+++ b/contrib/go/_std_1.19/src/runtime/sigtab_linux_generic.go
diff --git a/contrib/go/_std_1.18/src/runtime/sizeclasses.go b/contrib/go/_std_1.19/src/runtime/sizeclasses.go
index 067871eaf3..067871eaf3 100644
--- a/contrib/go/_std_1.18/src/runtime/sizeclasses.go
+++ b/contrib/go/_std_1.19/src/runtime/sizeclasses.go
diff --git a/contrib/go/_std_1.19/src/runtime/slice.go b/contrib/go/_std_1.19/src/runtime/slice.go
new file mode 100644
index 0000000000..2413a46d6a
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/slice.go
@@ -0,0 +1,344 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"internal/abi"
+	"internal/goarch"
+	"runtime/internal/math"
+	"runtime/internal/sys"
+	"unsafe"
+)
+
+type slice struct {
+	array unsafe.Pointer
+	len   int
+	cap   int
+}
+
+// A notInHeapSlice is a slice backed by go:notinheap memory.
+type notInHeapSlice struct {
+	array *notInHeap
+	len   int
+	cap   int
+}
+
+func panicmakeslicelen() {
+	panic(errorString("makeslice: len out of range"))
+}
+
+func panicmakeslicecap() {
+	panic(errorString("makeslice: cap out of range"))
+}
+
+// makeslicecopy allocates a slice of "tolen" elements of type "et",
+// then copies "fromlen" elements of type "et" into that new allocation from "from".
+func makeslicecopy(et *_type, tolen int, fromlen int, from unsafe.Pointer) unsafe.Pointer {
+	var tomem, copymem uintptr
+	if uintptr(tolen) > uintptr(fromlen) {
+		var overflow bool
+		tomem, overflow = math.MulUintptr(et.size, uintptr(tolen))
+		if overflow || tomem > maxAlloc || tolen < 0 {
+			panicmakeslicelen()
+		}
+		copymem = et.size * uintptr(fromlen)
+	} else {
+		// fromlen is a known good length providing and equal or greater than tolen,
+		// thereby making tolen a good slice length too as from and to slices have the
+		// same element width.
+		tomem = et.size * uintptr(tolen)
+		copymem = tomem
+	}
+
+	var to unsafe.Pointer
+	if et.ptrdata == 0 {
+		to = mallocgc(tomem, nil, false)
+		if copymem < tomem {
+			memclrNoHeapPointers(add(to, copymem), tomem-copymem)
+		}
+	} else {
+		// Note: can't use rawmem (which avoids zeroing of memory), because then GC can scan uninitialized memory.
+		to = mallocgc(tomem, et, true)
+		if copymem > 0 && writeBarrier.enabled {
+			// Only shade the pointers in old.array since we know the destination slice to
+			// only contains nil pointers because it has been cleared during alloc.
+			bulkBarrierPreWriteSrcOnly(uintptr(to), uintptr(from), copymem)
+		}
+	}
+
+	if raceenabled {
+		callerpc := getcallerpc()
+		pc := abi.FuncPCABIInternal(makeslicecopy)
+		racereadrangepc(from, copymem, callerpc, pc)
+	}
+	if msanenabled {
+		msanread(from, copymem)
+	}
+	if asanenabled {
+		asanread(from, copymem)
+	}
+
+	memmove(to, from, copymem)
+
+	return to
+}
+
+func makeslice(et *_type, len, cap int) unsafe.Pointer {
+	mem, overflow := math.MulUintptr(et.size, uintptr(cap))
+	if overflow || mem > maxAlloc || len < 0 || len > cap {
+		// NOTE: Produce a 'len out of range' error instead of a
+		// 'cap out of range' error when someone does make([]T, bignumber).
+		// 'cap out of range' is true too, but since the cap is only being
+		// supplied implicitly, saying len is clearer.
+		// See golang.org/issue/4085.
+		mem, overflow := math.MulUintptr(et.size, uintptr(len))
+		if overflow || mem > maxAlloc || len < 0 {
+			panicmakeslicelen()
+		}
+		panicmakeslicecap()
+	}
+
+	return mallocgc(mem, et, true)
+}
+
+func makeslice64(et *_type, len64, cap64 int64) unsafe.Pointer {
+	len := int(len64)
+	if int64(len) != len64 {
+		panicmakeslicelen()
+	}
+
+	cap := int(cap64)
+	if int64(cap) != cap64 {
+		panicmakeslicecap()
+	}
+
+	return makeslice(et, len, cap)
+}
+
+// This is a wrapper over runtime/internal/math.MulUintptr,
+// so the compiler can recognize and treat it as an intrinsic.
+func mulUintptr(a, b uintptr) (uintptr, bool) {
+	return math.MulUintptr(a, b)
+}
+
+// Keep this code in sync with cmd/compile/internal/walk/builtin.go:walkUnsafeSlice
+func unsafeslice(et *_type, ptr unsafe.Pointer, len int) {
+	if len < 0 {
+		panicunsafeslicelen()
+	}
+
+	mem, overflow := math.MulUintptr(et.size, uintptr(len))
+	if overflow || mem > -uintptr(ptr) {
+		if ptr == nil {
+			panicunsafeslicenilptr()
+		}
+		panicunsafeslicelen()
+	}
+}
+
+// Keep this code in sync with cmd/compile/internal/walk/builtin.go:walkUnsafeSlice
+func unsafeslice64(et *_type, ptr unsafe.Pointer, len64 int64) {
+	len := int(len64)
+	if int64(len) != len64 {
+		panicunsafeslicelen()
+	}
+	unsafeslice(et, ptr, len)
+}
+
+func unsafeslicecheckptr(et *_type, ptr unsafe.Pointer, len64 int64) {
+	unsafeslice64(et, ptr, len64)
+
+	// Check that underlying array doesn't straddle multiple heap objects.
+	// unsafeslice64 has already checked for overflow.
+	if checkptrStraddles(ptr, uintptr(len64)*et.size) {
+		throw("checkptr: unsafe.Slice result straddles multiple allocations")
+	}
+}
+
+func panicunsafeslicelen() {
+	panic(errorString("unsafe.Slice: len out of range"))
+}
+
+func panicunsafeslicenilptr() {
+	panic(errorString("unsafe.Slice: ptr is nil and len is not zero"))
+}
+
+// growslice handles slice growth during append.
+// It is passed the slice element type, the old slice, and the desired new minimum capacity,
+// and it returns a new slice with at least that capacity, with the old data
+// copied into it.
+// The new slice's length is set to the old slice's length,
+// NOT to the new requested capacity.
+// This is for codegen convenience. The old slice's length is used immediately
+// to calculate where to write new values during an append.
+// TODO: When the old backend is gone, reconsider this decision.
+// The SSA backend might prefer the new length or to return only ptr/cap and save stack space.
+func growslice(et *_type, old slice, cap int) slice {
+	if raceenabled {
+		callerpc := getcallerpc()
+		racereadrangepc(old.array, uintptr(old.len*int(et.size)), callerpc, abi.FuncPCABIInternal(growslice))
+	}
+	if msanenabled {
+		msanread(old.array, uintptr(old.len*int(et.size)))
+	}
+	if asanenabled {
+		asanread(old.array, uintptr(old.len*int(et.size)))
+	}
+
+	if cap < old.cap {
+		panic(errorString("growslice: cap out of range"))
+	}
+
+	if et.size == 0 {
+		// append should not create a slice with nil pointer but non-zero len.
+		// We assume that append doesn't need to preserve old.array in this case.
+		return slice{unsafe.Pointer(&zerobase), old.len, cap}
+	}
+
+	newcap := old.cap
+	doublecap := newcap + newcap
+	if cap > doublecap {
+		newcap = cap
+	} else {
+		const threshold = 256
+		if old.cap < threshold {
+			newcap = doublecap
+		} else {
+			// Check 0 < newcap to detect overflow
+			// and prevent an infinite loop.
+			for 0 < newcap && newcap < cap {
+				// Transition from growing 2x for small slices
+				// to growing 1.25x for large slices. This formula
+				// gives a smooth-ish transition between the two.
+				newcap += (newcap + 3*threshold) / 4
+			}
+			// Set newcap to the requested cap when
+			// the newcap calculation overflowed.
+			if newcap <= 0 {
+				newcap = cap
+			}
+		}
+	}
+
+	var overflow bool
+	var lenmem, newlenmem, capmem uintptr
+	// Specialize for common values of et.size.
+	// For 1 we don't need any division/multiplication.
+	// For goarch.PtrSize, compiler will optimize division/multiplication into a shift by a constant.
+	// For powers of 2, use a variable shift.
+	switch {
+	case et.size == 1:
+		lenmem = uintptr(old.len)
+		newlenmem = uintptr(cap)
+		capmem = roundupsize(uintptr(newcap))
+		overflow = uintptr(newcap) > maxAlloc
+		newcap = int(capmem)
+	case et.size == goarch.PtrSize:
+		lenmem = uintptr(old.len) * goarch.PtrSize
+		newlenmem = uintptr(cap) * goarch.PtrSize
+		capmem = roundupsize(uintptr(newcap) * goarch.PtrSize)
+		overflow = uintptr(newcap) > maxAlloc/goarch.PtrSize
+		newcap = int(capmem / goarch.PtrSize)
+	case isPowerOfTwo(et.size):
+		var shift uintptr
+		if goarch.PtrSize == 8 {
+			// Mask shift for better code generation.
+			shift = uintptr(sys.Ctz64(uint64(et.size))) & 63
+		} else {
+			shift = uintptr(sys.Ctz32(uint32(et.size))) & 31
+		}
+		lenmem = uintptr(old.len) << shift
+		newlenmem = uintptr(cap) << shift
+		capmem = roundupsize(uintptr(newcap) << shift)
+		overflow = uintptr(newcap) > (maxAlloc >> shift)
+		newcap = int(capmem >> shift)
+	default:
+		lenmem = uintptr(old.len) * et.size
+		newlenmem = uintptr(cap) * et.size
+		capmem, overflow = math.MulUintptr(et.size, uintptr(newcap))
+		capmem = roundupsize(capmem)
+		newcap = int(capmem / et.size)
+	}
+
+	// The check of overflow in addition to capmem > maxAlloc is needed
+	// to prevent an overflow which can be used to trigger a segfault
+	// on 32bit architectures with this example program:
+	//
+	// type T [1<<27 + 1]int64
+	//
+	// var d T
+	// var s []T
+	//
+	// func main() {
+	//   s = append(s, d, d, d, d)
+	//   print(len(s), "\n")
+	// }
+	if overflow || capmem > maxAlloc {
+		panic(errorString("growslice: cap out of range"))
+	}
+
+	var p unsafe.Pointer
+	if et.ptrdata == 0 {
+		p = mallocgc(capmem, nil, false)
+		// The append() that calls growslice is going to overwrite from old.len to cap (which will be the new length).
+		// Only clear the part that will not be overwritten.
+		memclrNoHeapPointers(add(p, newlenmem), capmem-newlenmem)
+	} else {
+		// Note: can't use rawmem (which avoids zeroing of memory), because then GC can scan uninitialized memory.
+		p = mallocgc(capmem, et, true)
+		if lenmem > 0 && writeBarrier.enabled {
+			// Only shade the pointers in old.array since we know the destination slice p
+			// only contains nil pointers because it has been cleared during alloc.
+			bulkBarrierPreWriteSrcOnly(uintptr(p), uintptr(old.array), lenmem-et.size+et.ptrdata)
+		}
+	}
+	memmove(p, old.array, lenmem)
+
+	return slice{p, old.len, newcap}
+}
+
+func isPowerOfTwo(x uintptr) bool {
+	return x&(x-1) == 0
+}
+
+// slicecopy is used to copy from a string or slice of pointerless elements into a slice.
+func slicecopy(toPtr unsafe.Pointer, toLen int, fromPtr unsafe.Pointer, fromLen int, width uintptr) int {
+	if fromLen == 0 || toLen == 0 {
+		return 0
+	}
+
+	n := fromLen
+	if toLen < n {
+		n = toLen
+	}
+
+	if width == 0 {
+		return n
+	}
+
+	size := uintptr(n) * width
+	if raceenabled {
+		callerpc := getcallerpc()
+		pc := abi.FuncPCABIInternal(slicecopy)
+		racereadrangepc(fromPtr, size, callerpc, pc)
+		racewriterangepc(toPtr, size, callerpc, pc)
+	}
+	if msanenabled {
+		msanread(fromPtr, size)
+		msanwrite(toPtr, size)
+	}
+	if asanenabled {
+		asanread(fromPtr, size)
+		asanwrite(toPtr, size)
+	}
+
+	if size == 1 { // common case worth about 2x to do here
+		// TODO: is this still worth it with new memmove impl?
+		*(*byte)(toPtr) = *(*byte)(fromPtr) // known to be a byte pointer
+	} else {
+		memmove(toPtr, fromPtr, size)
+	}
+	return n
+}
diff --git a/contrib/go/_std_1.18/src/runtime/softfloat64.go b/contrib/go/_std_1.19/src/runtime/softfloat64.go
index 42ef009297..42ef009297 100644
--- a/contrib/go/_std_1.18/src/runtime/softfloat64.go
+++ b/contrib/go/_std_1.19/src/runtime/softfloat64.go
diff --git a/contrib/go/_std_1.19/src/runtime/stack.go b/contrib/go/_std_1.19/src/runtime/stack.go
new file mode 100644
index 0000000000..2a7f0bd1c3
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/stack.go
@@ -0,0 +1,1484 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"internal/abi"
+	"internal/cpu"
+	"internal/goarch"
+	"internal/goos"
+	"runtime/internal/atomic"
+	"runtime/internal/sys"
+	"unsafe"
+)
+
+/*
+Stack layout parameters.
+Included both by runtime (compiled via 6c) and linkers (compiled via gcc).
+
+The per-goroutine g->stackguard is set to point StackGuard bytes
+above the bottom of the stack.  Each function compares its stack
+pointer against g->stackguard to check for overflow.  To cut one
+instruction from the check sequence for functions with tiny frames,
+the stack is allowed to protrude StackSmall bytes below the stack
+guard.  Functions with large frames don't bother with the check and
+always call morestack.  The sequences are (for amd64, others are
+similar):
+
+	guard = g->stackguard
+	frame = function's stack frame size
+	argsize = size of function arguments (call + return)
+
+	stack frame size <= StackSmall:
+		CMPQ guard, SP
+		JHI 3(PC)
+		MOVQ m->morearg, $(argsize << 32)
+		CALL morestack(SB)
+
+	stack frame size > StackSmall but < StackBig
+		LEAQ (frame-StackSmall)(SP), R0
+		CMPQ guard, R0
+		JHI 3(PC)
+		MOVQ m->morearg, $(argsize << 32)
+		CALL morestack(SB)
+
+	stack frame size >= StackBig:
+		MOVQ m->morearg, $((argsize << 32) | frame)
+		CALL morestack(SB)
+
+The bottom StackGuard - StackSmall bytes are important: there has
+to be enough room to execute functions that refuse to check for
+stack overflow, either because they need to be adjacent to the
+actual caller's frame (deferproc) or because they handle the imminent
+stack overflow (morestack).
+
+For example, deferproc might call malloc, which does one of the
+above checks (without allocating a full frame), which might trigger
+a call to morestack.  This sequence needs to fit in the bottom
+section of the stack.  On amd64, morestack's frame is 40 bytes, and
+deferproc's frame is 56 bytes.  That fits well within the
+StackGuard - StackSmall bytes at the bottom.
+The linkers explore all possible call traces involving non-splitting
+functions to make sure that this limit cannot be violated.
+*/
+
+const (
+	// StackSystem is a number of additional bytes to add
+	// to each stack below the usual guard area for OS-specific
+	// purposes like signal handling. Used on Windows, Plan 9,
+	// and iOS because they do not use a separate stack.
+	_StackSystem = goos.IsWindows*512*goarch.PtrSize + goos.IsPlan9*512 + goos.IsIos*goarch.IsArm64*1024
+
+	// The minimum size of stack used by Go code
+	_StackMin = 2048
+
+	// The minimum stack size to allocate.
+	// The hackery here rounds FixedStack0 up to a power of 2.
+	_FixedStack0 = _StackMin + _StackSystem
+	_FixedStack1 = _FixedStack0 - 1
+	_FixedStack2 = _FixedStack1 | (_FixedStack1 >> 1)
+	_FixedStack3 = _FixedStack2 | (_FixedStack2 >> 2)
+	_FixedStack4 = _FixedStack3 | (_FixedStack3 >> 4)
+	_FixedStack5 = _FixedStack4 | (_FixedStack4 >> 8)
+	_FixedStack6 = _FixedStack5 | (_FixedStack5 >> 16)
+	_FixedStack  = _FixedStack6 + 1
+
+	// Functions that need frames bigger than this use an extra
+	// instruction to do the stack split check, to avoid overflow
+	// in case SP - framesize wraps below zero.
+	// This value can be no bigger than the size of the unmapped
+	// space at zero.
+	_StackBig = 4096
+
+	// The stack guard is a pointer this many bytes above the
+	// bottom of the stack.
+	//
+	// The guard leaves enough room for one _StackSmall frame plus
+	// a _StackLimit chain of NOSPLIT calls plus _StackSystem
+	// bytes for the OS.
+	_StackGuard = 928*sys.StackGuardMultiplier + _StackSystem
+
+	// After a stack split check the SP is allowed to be this
+	// many bytes below the stack guard. This saves an instruction
+	// in the checking sequence for tiny frames.
+	_StackSmall = 128
+
+	// The maximum number of bytes that a chain of NOSPLIT
+	// functions can use.
+	_StackLimit = _StackGuard - _StackSystem - _StackSmall
+)
+
+const (
+	// stackDebug == 0: no logging
+	//            == 1: logging of per-stack operations
+	//            == 2: logging of per-frame operations
+	//            == 3: logging of per-word updates
+	//            == 4: logging of per-word reads
+	stackDebug       = 0
+	stackFromSystem  = 0 // allocate stacks from system memory instead of the heap
+	stackFaultOnFree = 0 // old stacks are mapped noaccess to detect use after free
+	stackPoisonCopy  = 0 // fill stack that should not be accessed with garbage, to detect bad dereferences during copy
+	stackNoCache     = 0 // disable per-P small stack caches
+
+	// check the BP links during traceback.
+	debugCheckBP = false
+)
+
+const (
+	uintptrMask = 1<<(8*goarch.PtrSize) - 1
+
+	// The values below can be stored to g.stackguard0 to force
+	// the next stack check to fail.
+	// These are all larger than any real SP.
+
+	// Goroutine preemption request.
+	// 0xfffffade in hex.
+	stackPreempt = uintptrMask & -1314
+
+	// Thread is forking. Causes a split stack check failure.
+	// 0xfffffb2e in hex.
+	stackFork = uintptrMask & -1234
+
+	// Force a stack movement. Used for debugging.
+	// 0xfffffeed in hex.
+	stackForceMove = uintptrMask & -275
+
+	// stackPoisonMin is the lowest allowed stack poison value.
+	stackPoisonMin = uintptrMask & -4096
+)
+
+// Global pool of spans that have free stacks.
+// Stacks are assigned an order according to size.
+//
+//	order = log_2(size/FixedStack)
+//
+// There is a free list for each order.
+var stackpool [_NumStackOrders]struct {
+	item stackpoolItem
+	_    [cpu.CacheLinePadSize - unsafe.Sizeof(stackpoolItem{})%cpu.CacheLinePadSize]byte
+}
+
+//go:notinheap
+type stackpoolItem struct {
+	mu   mutex
+	span mSpanList
+}
+
+// Global pool of large stack spans.
+var stackLarge struct {
+	lock mutex
+	free [heapAddrBits - pageShift]mSpanList // free lists by log_2(s.npages)
+}
+
+func stackinit() {
+	if _StackCacheSize&_PageMask != 0 {
+		throw("cache size must be a multiple of page size")
+	}
+	for i := range stackpool {
+		stackpool[i].item.span.init()
+		lockInit(&stackpool[i].item.mu, lockRankStackpool)
+	}
+	for i := range stackLarge.free {
+		stackLarge.free[i].init()
+		lockInit(&stackLarge.lock, lockRankStackLarge)
+	}
+}
+
+// stacklog2 returns ⌊log_2(n)⌋.
+func stacklog2(n uintptr) int {
+	log2 := 0
+	for n > 1 {
+		n >>= 1
+		log2++
+	}
+	return log2
+}
+
+// Allocates a stack from the free pool. Must be called with
+// stackpool[order].item.mu held.
+func stackpoolalloc(order uint8) gclinkptr {
+	list := &stackpool[order].item.span
+	s := list.first
+	lockWithRankMayAcquire(&mheap_.lock, lockRankMheap)
+	if s == nil {
+		// no free stacks. Allocate another span worth.
+		s = mheap_.allocManual(_StackCacheSize>>_PageShift, spanAllocStack)
+		if s == nil {
+			throw("out of memory")
+		}
+		if s.allocCount != 0 {
+			throw("bad allocCount")
+		}
+		if s.manualFreeList.ptr() != nil {
+			throw("bad manualFreeList")
+		}
+		osStackAlloc(s)
+		s.elemsize = _FixedStack << order
+		for i := uintptr(0); i < _StackCacheSize; i += s.elemsize {
+			x := gclinkptr(s.base() + i)
+			x.ptr().next = s.manualFreeList
+			s.manualFreeList = x
+		}
+		list.insert(s)
+	}
+	x := s.manualFreeList
+	if x.ptr() == nil {
+		throw("span has no free stacks")
+	}
+	s.manualFreeList = x.ptr().next
+	s.allocCount++
+	if s.manualFreeList.ptr() == nil {
+		// all stacks in s are allocated.
+		list.remove(s)
+	}
+	return x
+}
+
+// Adds stack x to the free pool. Must be called with stackpool[order].item.mu held.
+func stackpoolfree(x gclinkptr, order uint8) {
+	s := spanOfUnchecked(uintptr(x))
+	if s.state.get() != mSpanManual {
+		throw("freeing stack not in a stack span")
+	}
+	if s.manualFreeList.ptr() == nil {
+		// s will now have a free stack
+		stackpool[order].item.span.insert(s)
+	}
+	x.ptr().next = s.manualFreeList
+	s.manualFreeList = x
+	s.allocCount--
+	if gcphase == _GCoff && s.allocCount == 0 {
+		// Span is completely free. Return it to the heap
+		// immediately if we're sweeping.
+		//
+		// If GC is active, we delay the free until the end of
+		// GC to avoid the following type of situation:
+		//
+		// 1) GC starts, scans a SudoG but does not yet mark the SudoG.elem pointer
+		// 2) The stack that pointer points to is copied
+		// 3) The old stack is freed
+		// 4) The containing span is marked free
+		// 5) GC attempts to mark the SudoG.elem pointer. The
+		//    marking fails because the pointer looks like a
+		//    pointer into a free span.
+		//
+		// By not freeing, we prevent step #4 until GC is done.
+		stackpool[order].item.span.remove(s)
+		s.manualFreeList = 0
+		osStackFree(s)
+		mheap_.freeManual(s, spanAllocStack)
+	}
+}
+
+// stackcacherefill/stackcacherelease implement a global pool of stack segments.
+// The pool is required to prevent unlimited growth of per-thread caches.
+//
+//go:systemstack
+func stackcacherefill(c *mcache, order uint8) {
+	if stackDebug >= 1 {
+		print("stackcacherefill order=", order, "\n")
+	}
+
+	// Grab some stacks from the global cache.
+	// Grab half of the allowed capacity (to prevent thrashing).
+	var list gclinkptr
+	var size uintptr
+	lock(&stackpool[order].item.mu)
+	for size < _StackCacheSize/2 {
+		x := stackpoolalloc(order)
+		x.ptr().next = list
+		list = x
+		size += _FixedStack << order
+	}
+	unlock(&stackpool[order].item.mu)
+	c.stackcache[order].list = list
+	c.stackcache[order].size = size
+}
+
+//go:systemstack
+func stackcacherelease(c *mcache, order uint8) {
+	if stackDebug >= 1 {
+		print("stackcacherelease order=", order, "\n")
+	}
+	x := c.stackcache[order].list
+	size := c.stackcache[order].size
+	lock(&stackpool[order].item.mu)
+	for size > _StackCacheSize/2 {
+		y := x.ptr().next
+		stackpoolfree(x, order)
+		x = y
+		size -= _FixedStack << order
+	}
+	unlock(&stackpool[order].item.mu)
+	c.stackcache[order].list = x
+	c.stackcache[order].size = size
+}
+
+//go:systemstack
+func stackcache_clear(c *mcache) {
+	if stackDebug >= 1 {
+		print("stackcache clear\n")
+	}
+	for order := uint8(0); order < _NumStackOrders; order++ {
+		lock(&stackpool[order].item.mu)
+		x := c.stackcache[order].list
+		for x.ptr() != nil {
+			y := x.ptr().next
+			stackpoolfree(x, order)
+			x = y
+		}
+		c.stackcache[order].list = 0
+		c.stackcache[order].size = 0
+		unlock(&stackpool[order].item.mu)
+	}
+}
+
+// stackalloc allocates an n byte stack.
+//
+// stackalloc must run on the system stack because it uses per-P
+// resources and must not split the stack.
+//
+//go:systemstack
+func stackalloc(n uint32) stack {
+	// Stackalloc must be called on scheduler stack, so that we
+	// never try to grow the stack during the code that stackalloc runs.
+	// Doing so would cause a deadlock (issue 1547).
+	thisg := getg()
+	if thisg != thisg.m.g0 {
+		throw("stackalloc not on scheduler stack")
+	}
+	if n&(n-1) != 0 {
+		throw("stack size not a power of 2")
+	}
+	if stackDebug >= 1 {
+		print("stackalloc ", n, "\n")
+	}
+
+	if debug.efence != 0 || stackFromSystem != 0 {
+		n = uint32(alignUp(uintptr(n), physPageSize))
+		v := sysAlloc(uintptr(n), &memstats.stacks_sys)
+		if v == nil {
+			throw("out of memory (stackalloc)")
+		}
+		return stack{uintptr(v), uintptr(v) + uintptr(n)}
+	}
+
+	// Small stacks are allocated with a fixed-size free-list allocator.
+	// If we need a stack of a bigger size, we fall back on allocating
+	// a dedicated span.
+	var v unsafe.Pointer
+	if n < _FixedStack<<_NumStackOrders && n < _StackCacheSize {
+		order := uint8(0)
+		n2 := n
+		for n2 > _FixedStack {
+			order++
+			n2 >>= 1
+		}
+		var x gclinkptr
+		if stackNoCache != 0 || thisg.m.p == 0 || thisg.m.preemptoff != "" {
+			// thisg.m.p == 0 can happen in the guts of exitsyscall
+			// or procresize. Just get a stack from the global pool.
+			// Also don't touch stackcache during gc
+			// as it's flushed concurrently.
+			lock(&stackpool[order].item.mu)
+			x = stackpoolalloc(order)
+			unlock(&stackpool[order].item.mu)
+		} else {
+			c := thisg.m.p.ptr().mcache
+			x = c.stackcache[order].list
+			if x.ptr() == nil {
+				stackcacherefill(c, order)
+				x = c.stackcache[order].list
+			}
+			c.stackcache[order].list = x.ptr().next
+			c.stackcache[order].size -= uintptr(n)
+		}
+		v = unsafe.Pointer(x)
+	} else {
+		var s *mspan
+		npage := uintptr(n) >> _PageShift
+		log2npage := stacklog2(npage)
+
+		// Try to get a stack from the large stack cache.
+		lock(&stackLarge.lock)
+		if !stackLarge.free[log2npage].isEmpty() {
+			s = stackLarge.free[log2npage].first
+			stackLarge.free[log2npage].remove(s)
+		}
+		unlock(&stackLarge.lock)
+
+		lockWithRankMayAcquire(&mheap_.lock, lockRankMheap)
+
+		if s == nil {
+			// Allocate a new stack from the heap.
+			s = mheap_.allocManual(npage, spanAllocStack)
+			if s == nil {
+				throw("out of memory")
+			}
+			osStackAlloc(s)
+			s.elemsize = uintptr(n)
+		}
+		v = unsafe.Pointer(s.base())
+	}
+
+	if raceenabled {
+		racemalloc(v, uintptr(n))
+	}
+	if msanenabled {
+		msanmalloc(v, uintptr(n))
+	}
+	if asanenabled {
+		asanunpoison(v, uintptr(n))
+	}
+	if stackDebug >= 1 {
+		print("  allocated ", v, "\n")
+	}
+	return stack{uintptr(v), uintptr(v) + uintptr(n)}
+}
+
+// stackfree frees an n byte stack allocation at stk.
+//
+// stackfree must run on the system stack because it uses per-P
+// resources and must not split the stack.
+//
+//go:systemstack
+func stackfree(stk stack) {
+	gp := getg()
+	v := unsafe.Pointer(stk.lo)
+	n := stk.hi - stk.lo
+	if n&(n-1) != 0 {
+		throw("stack not a power of 2")
+	}
+	if stk.lo+n < stk.hi {
+		throw("bad stack size")
+	}
+	if stackDebug >= 1 {
+		println("stackfree", v, n)
+		memclrNoHeapPointers(v, n) // for testing, clobber stack data
+	}
+	if debug.efence != 0 || stackFromSystem != 0 {
+		if debug.efence != 0 || stackFaultOnFree != 0 {
+			sysFault(v, n)
+		} else {
+			sysFree(v, n, &memstats.stacks_sys)
+		}
+		return
+	}
+	if msanenabled {
+		msanfree(v, n)
+	}
+	if asanenabled {
+		asanpoison(v, n)
+	}
+	if n < _FixedStack<<_NumStackOrders && n < _StackCacheSize {
+		order := uint8(0)
+		n2 := n
+		for n2 > _FixedStack {
+			order++
+			n2 >>= 1
+		}
+		x := gclinkptr(v)
+		if stackNoCache != 0 || gp.m.p == 0 || gp.m.preemptoff != "" {
+			lock(&stackpool[order].item.mu)
+			stackpoolfree(x, order)
+			unlock(&stackpool[order].item.mu)
+		} else {
+			c := gp.m.p.ptr().mcache
+			if c.stackcache[order].size >= _StackCacheSize {
+				stackcacherelease(c, order)
+			}
+			x.ptr().next = c.stackcache[order].list
+			c.stackcache[order].list = x
+			c.stackcache[order].size += n
+		}
+	} else {
+		s := spanOfUnchecked(uintptr(v))
+		if s.state.get() != mSpanManual {
+			println(hex(s.base()), v)
+			throw("bad span state")
+		}
+		if gcphase == _GCoff {
+			// Free the stack immediately if we're
+			// sweeping.
+			osStackFree(s)
+			mheap_.freeManual(s, spanAllocStack)
+		} else {
+			// If the GC is running, we can't return a
+			// stack span to the heap because it could be
+			// reused as a heap span, and this state
+			// change would race with GC. Add it to the
+			// large stack cache instead.
+			log2npage := stacklog2(s.npages)
+			lock(&stackLarge.lock)
+			stackLarge.free[log2npage].insert(s)
+			unlock(&stackLarge.lock)
+		}
+	}
+}
+
+var maxstacksize uintptr = 1 << 20 // enough until runtime.main sets it for real
+
+var maxstackceiling = maxstacksize
+
+var ptrnames = []string{
+	0: "scalar",
+	1: "ptr",
+}
+
+// Stack frame layout
+//
+// (x86)
+// +------------------+
+// | args from caller |
+// +------------------+ <- frame->argp
+// |  return address  |
+// +------------------+
+// |  caller's BP (*) | (*) if framepointer_enabled && varp < sp
+// +------------------+ <- frame->varp
+// |     locals       |
+// +------------------+
+// |  args to callee  |
+// +------------------+ <- frame->sp
+//
+// (arm)
+// +------------------+
+// | args from caller |
+// +------------------+ <- frame->argp
+// | caller's retaddr |
+// +------------------+ <- frame->varp
+// |     locals       |
+// +------------------+
+// |  args to callee  |
+// +------------------+
+// |  return address  |
+// +------------------+ <- frame->sp
+
+type adjustinfo struct {
+	old   stack
+	delta uintptr // ptr distance from old to new stack (newbase - oldbase)
+	cache pcvalueCache
+
+	// sghi is the highest sudog.elem on the stack.
+	sghi uintptr
+}
+
+// Adjustpointer checks whether *vpp is in the old stack described by adjinfo.
+// If so, it rewrites *vpp to point into the new stack.
+func adjustpointer(adjinfo *adjustinfo, vpp unsafe.Pointer) {
+	pp := (*uintptr)(vpp)
+	p := *pp
+	if stackDebug >= 4 {
+		print("        ", pp, ":", hex(p), "\n")
+	}
+	if adjinfo.old.lo <= p && p < adjinfo.old.hi {
+		*pp = p + adjinfo.delta
+		if stackDebug >= 3 {
+			print("        adjust ptr ", pp, ":", hex(p), " -> ", hex(*pp), "\n")
+		}
+	}
+}
+
+// Information from the compiler about the layout of stack frames.
+// Note: this type must agree with reflect.bitVector.
+type bitvector struct {
+	n        int32 // # of bits
+	bytedata *uint8
+}
+
+// ptrbit returns the i'th bit in bv.
+// ptrbit is less efficient than iterating directly over bitvector bits,
+// and should only be used in non-performance-critical code.
+// See adjustpointers for an example of a high-efficiency walk of a bitvector.
+func (bv *bitvector) ptrbit(i uintptr) uint8 {
+	b := *(addb(bv.bytedata, i/8))
+	return (b >> (i % 8)) & 1
+}
+
+// bv describes the memory starting at address scanp.
+// Adjust any pointers contained therein.
+func adjustpointers(scanp unsafe.Pointer, bv *bitvector, adjinfo *adjustinfo, f funcInfo) {
+	minp := adjinfo.old.lo
+	maxp := adjinfo.old.hi
+	delta := adjinfo.delta
+	num := uintptr(bv.n)
+	// If this frame might contain channel receive slots, use CAS
+	// to adjust pointers. If the slot hasn't been received into
+	// yet, it may contain stack pointers and a concurrent send
+	// could race with adjusting those pointers. (The sent value
+	// itself can never contain stack pointers.)
+	useCAS := uintptr(scanp) < adjinfo.sghi
+	for i := uintptr(0); i < num; i += 8 {
+		if stackDebug >= 4 {
+			for j := uintptr(0); j < 8; j++ {
+				print("        ", add(scanp, (i+j)*goarch.PtrSize), ":", ptrnames[bv.ptrbit(i+j)], ":", hex(*(*uintptr)(add(scanp, (i+j)*goarch.PtrSize))), " # ", i, " ", *addb(bv.bytedata, i/8), "\n")
+			}
+		}
+		b := *(addb(bv.bytedata, i/8))
+		for b != 0 {
+			j := uintptr(sys.Ctz8(b))
+			b &= b - 1
+			pp := (*uintptr)(add(scanp, (i+j)*goarch.PtrSize))
+		retry:
+			p := *pp
+			if f.valid() && 0 < p && p < minLegalPointer && debug.invalidptr != 0 {
+				// Looks like a junk value in a pointer slot.
+				// Live analysis wrong?
+				getg().m.traceback = 2
+				print("runtime: bad pointer in frame ", funcname(f), " at ", pp, ": ", hex(p), "\n")
+				throw("invalid pointer found on stack")
+			}
+			if minp <= p && p < maxp {
+				if stackDebug >= 3 {
+					print("adjust ptr ", hex(p), " ", funcname(f), "\n")
+				}
+				if useCAS {
+					ppu := (*unsafe.Pointer)(unsafe.Pointer(pp))
+					if !atomic.Casp1(ppu, unsafe.Pointer(p), unsafe.Pointer(p+delta)) {
+						goto retry
+					}
+				} else {
+					*pp = p + delta
+				}
+			}
+		}
+	}
+}
+
+// Note: the argument/return area is adjusted by the callee.
+func adjustframe(frame *stkframe, arg unsafe.Pointer) bool {
+	adjinfo := (*adjustinfo)(arg)
+	if frame.continpc == 0 {
+		// Frame is dead.
+		return true
+	}
+	f := frame.fn
+	if stackDebug >= 2 {
+		print("    adjusting ", funcname(f), " frame=[", hex(frame.sp), ",", hex(frame.fp), "] pc=", hex(frame.pc), " continpc=", hex(frame.continpc), "\n")
+	}
+	if f.funcID == funcID_systemstack_switch {
+		// A special routine at the bottom of stack of a goroutine that does a systemstack call.
+		// We will allow it to be copied even though we don't
+		// have full GC info for it (because it is written in asm).
+		return true
+	}
+
+	locals, args, objs := getStackMap(frame, &adjinfo.cache, true)
+
+	// Adjust local variables if stack frame has been allocated.
+	if locals.n > 0 {
+		size := uintptr(locals.n) * goarch.PtrSize
+		adjustpointers(unsafe.Pointer(frame.varp-size), &locals, adjinfo, f)
+	}
+
+	// Adjust saved base pointer if there is one.
+	// TODO what about arm64 frame pointer adjustment?
+	if goarch.ArchFamily == goarch.AMD64 && frame.argp-frame.varp == 2*goarch.PtrSize {
+		if stackDebug >= 3 {
+			print("      saved bp\n")
+		}
+		if debugCheckBP {
+			// Frame pointers should always point to the next higher frame on
+			// the Go stack (or be nil, for the top frame on the stack).
+			bp := *(*uintptr)(unsafe.Pointer(frame.varp))
+			if bp != 0 && (bp < adjinfo.old.lo || bp >= adjinfo.old.hi) {
+				println("runtime: found invalid frame pointer")
+				print("bp=", hex(bp), " min=", hex(adjinfo.old.lo), " max=", hex(adjinfo.old.hi), "\n")
+				throw("bad frame pointer")
+			}
+		}
+		adjustpointer(adjinfo, unsafe.Pointer(frame.varp))
+	}
+
+	// Adjust arguments.
+	if args.n > 0 {
+		if stackDebug >= 3 {
+			print("      args\n")
+		}
+		adjustpointers(unsafe.Pointer(frame.argp), &args, adjinfo, funcInfo{})
+	}
+
+	// Adjust pointers in all stack objects (whether they are live or not).
+	// See comments in mgcmark.go:scanframeworker.
+	if frame.varp != 0 {
+		for i := range objs {
+			obj := &objs[i]
+			off := obj.off
+			base := frame.varp // locals base pointer
+			if off >= 0 {
+				base = frame.argp // arguments and return values base pointer
+			}
+			p := base + uintptr(off)
+			if p < frame.sp {
+				// Object hasn't been allocated in the frame yet.
+				// (Happens when the stack bounds check fails and
+				// we call into morestack.)
+				continue
+			}
+			ptrdata := obj.ptrdata()
+			gcdata := obj.gcdata()
+			var s *mspan
+			if obj.useGCProg() {
+				// See comments in mgcmark.go:scanstack
+				s = materializeGCProg(ptrdata, gcdata)
+				gcdata = (*byte)(unsafe.Pointer(s.startAddr))
+			}
+			for i := uintptr(0); i < ptrdata; i += goarch.PtrSize {
+				if *addb(gcdata, i/(8*goarch.PtrSize))>>(i/goarch.PtrSize&7)&1 != 0 {
+					adjustpointer(adjinfo, unsafe.Pointer(p+i))
+				}
+			}
+			if s != nil {
+				dematerializeGCProg(s)
+			}
+		}
+	}
+
+	return true
+}
+
+func adjustctxt(gp *g, adjinfo *adjustinfo) {
+	adjustpointer(adjinfo, unsafe.Pointer(&gp.sched.ctxt))
+	if !framepointer_enabled {
+		return
+	}
+	if debugCheckBP {
+		bp := gp.sched.bp
+		if bp != 0 && (bp < adjinfo.old.lo || bp >= adjinfo.old.hi) {
+			println("runtime: found invalid top frame pointer")
+			print("bp=", hex(bp), " min=", hex(adjinfo.old.lo), " max=", hex(adjinfo.old.hi), "\n")
+			throw("bad top frame pointer")
+		}
+	}
+	adjustpointer(adjinfo, unsafe.Pointer(&gp.sched.bp))
+}
+
+func adjustdefers(gp *g, adjinfo *adjustinfo) {
+	// Adjust pointers in the Defer structs.
+	// We need to do this first because we need to adjust the
+	// defer.link fields so we always work on the new stack.
+	adjustpointer(adjinfo, unsafe.Pointer(&gp._defer))
+	for d := gp._defer; d != nil; d = d.link {
+		adjustpointer(adjinfo, unsafe.Pointer(&d.fn))
+		adjustpointer(adjinfo, unsafe.Pointer(&d.sp))
+		adjustpointer(adjinfo, unsafe.Pointer(&d._panic))
+		adjustpointer(adjinfo, unsafe.Pointer(&d.link))
+		adjustpointer(adjinfo, unsafe.Pointer(&d.varp))
+		adjustpointer(adjinfo, unsafe.Pointer(&d.fd))
+	}
+}
+
+func adjustpanics(gp *g, adjinfo *adjustinfo) {
+	// Panics are on stack and already adjusted.
+	// Update pointer to head of list in G.
+	adjustpointer(adjinfo, unsafe.Pointer(&gp._panic))
+}
+
+func adjustsudogs(gp *g, adjinfo *adjustinfo) {
+	// the data elements pointed to by a SudoG structure
+	// might be in the stack.
+	for s := gp.waiting; s != nil; s = s.waitlink {
+		adjustpointer(adjinfo, unsafe.Pointer(&s.elem))
+	}
+}
+
+func fillstack(stk stack, b byte) {
+	for p := stk.lo; p < stk.hi; p++ {
+		*(*byte)(unsafe.Pointer(p)) = b
+	}
+}
+
+func findsghi(gp *g, stk stack) uintptr {
+	var sghi uintptr
+	for sg := gp.waiting; sg != nil; sg = sg.waitlink {
+		p := uintptr(sg.elem) + uintptr(sg.c.elemsize)
+		if stk.lo <= p && p < stk.hi && p > sghi {
+			sghi = p
+		}
+	}
+	return sghi
+}
+
+// syncadjustsudogs adjusts gp's sudogs and copies the part of gp's
+// stack they refer to while synchronizing with concurrent channel
+// operations. It returns the number of bytes of stack copied.
+func syncadjustsudogs(gp *g, used uintptr, adjinfo *adjustinfo) uintptr {
+	if gp.waiting == nil {
+		return 0
+	}
+
+	// Lock channels to prevent concurrent send/receive.
+	var lastc *hchan
+	for sg := gp.waiting; sg != nil; sg = sg.waitlink {
+		if sg.c != lastc {
+			// There is a ranking cycle here between gscan bit and
+			// hchan locks. Normally, we only allow acquiring hchan
+			// locks and then getting a gscan bit. In this case, we
+			// already have the gscan bit. We allow acquiring hchan
+			// locks here as a special case, since a deadlock can't
+			// happen because the G involved must already be
+			// suspended. So, we get a special hchan lock rank here
+			// that is lower than gscan, but doesn't allow acquiring
+			// any other locks other than hchan.
+			lockWithRank(&sg.c.lock, lockRankHchanLeaf)
+		}
+		lastc = sg.c
+	}
+
+	// Adjust sudogs.
+	adjustsudogs(gp, adjinfo)
+
+	// Copy the part of the stack the sudogs point in to
+	// while holding the lock to prevent races on
+	// send/receive slots.
+	var sgsize uintptr
+	if adjinfo.sghi != 0 {
+		oldBot := adjinfo.old.hi - used
+		newBot := oldBot + adjinfo.delta
+		sgsize = adjinfo.sghi - oldBot
+		memmove(unsafe.Pointer(newBot), unsafe.Pointer(oldBot), sgsize)
+	}
+
+	// Unlock channels.
+	lastc = nil
+	for sg := gp.waiting; sg != nil; sg = sg.waitlink {
+		if sg.c != lastc {
+			unlock(&sg.c.lock)
+		}
+		lastc = sg.c
+	}
+
+	return sgsize
+}
+
+// Copies gp's stack to a new stack of a different size.
+// Caller must have changed gp status to Gcopystack.
+func copystack(gp *g, newsize uintptr) {
+	if gp.syscallsp != 0 {
+		throw("stack growth not allowed in system call")
+	}
+	old := gp.stack
+	if old.lo == 0 {
+		throw("nil stackbase")
+	}
+	used := old.hi - gp.sched.sp
+	// Add just the difference to gcController.addScannableStack.
+	// g0 stacks never move, so this will never account for them.
+	// It's also fine if we have no P, addScannableStack can deal with
+	// that case.
+	gcController.addScannableStack(getg().m.p.ptr(), int64(newsize)-int64(old.hi-old.lo))
+
+	// allocate new stack
+	new := stackalloc(uint32(newsize))
+	if stackPoisonCopy != 0 {
+		fillstack(new, 0xfd)
+	}
+	if stackDebug >= 1 {
+		print("copystack gp=", gp, " [", hex(old.lo), " ", hex(old.hi-used), " ", hex(old.hi), "]", " -> [", hex(new.lo), " ", hex(new.hi-used), " ", hex(new.hi), "]/", newsize, "\n")
+	}
+
+	// Compute adjustment.
+	var adjinfo adjustinfo
+	adjinfo.old = old
+	adjinfo.delta = new.hi - old.hi
+
+	// Adjust sudogs, synchronizing with channel ops if necessary.
+	ncopy := used
+	if !gp.activeStackChans {
+		if newsize < old.hi-old.lo && atomic.Load8(&gp.parkingOnChan) != 0 {
+			// It's not safe for someone to shrink this stack while we're actively
+			// parking on a channel, but it is safe to grow since we do that
+			// ourselves and explicitly don't want to synchronize with channels
+			// since we could self-deadlock.
+			throw("racy sudog adjustment due to parking on channel")
+		}
+		adjustsudogs(gp, &adjinfo)
+	} else {
+		// sudogs may be pointing in to the stack and gp has
+		// released channel locks, so other goroutines could
+		// be writing to gp's stack. Find the highest such
+		// pointer so we can handle everything there and below
+		// carefully. (This shouldn't be far from the bottom
+		// of the stack, so there's little cost in handling
+		// everything below it carefully.)
+		adjinfo.sghi = findsghi(gp, old)
+
+		// Synchronize with channel ops and copy the part of
+		// the stack they may interact with.
+		ncopy -= syncadjustsudogs(gp, used, &adjinfo)
+	}
+
+	// Copy the stack (or the rest of it) to the new location
+	memmove(unsafe.Pointer(new.hi-ncopy), unsafe.Pointer(old.hi-ncopy), ncopy)
+
+	// Adjust remaining structures that have pointers into stacks.
+	// We have to do most of these before we traceback the new
+	// stack because gentraceback uses them.
+	adjustctxt(gp, &adjinfo)
+	adjustdefers(gp, &adjinfo)
+	adjustpanics(gp, &adjinfo)
+	if adjinfo.sghi != 0 {
+		adjinfo.sghi += adjinfo.delta
+	}
+
+	// Swap out old stack for new one
+	gp.stack = new
+	gp.stackguard0 = new.lo + _StackGuard // NOTE: might clobber a preempt request
+	gp.sched.sp = new.hi - used
+	gp.stktopsp += adjinfo.delta
+
+	// Adjust pointers in the new stack.
+	gentraceback(^uintptr(0), ^uintptr(0), 0, gp, 0, nil, 0x7fffffff, adjustframe, noescape(unsafe.Pointer(&adjinfo)), 0)
+
+	// free old stack
+	if stackPoisonCopy != 0 {
+		fillstack(old, 0xfc)
+	}
+	stackfree(old)
+}
+
+// round x up to a power of 2.
+func round2(x int32) int32 {
+	s := uint(0)
+	for 1<<s < x {
+		s++
+	}
+	return 1 << s
+}
+
+// Called from runtime·morestack when more stack is needed.
+// Allocate larger stack and relocate to new stack.
+// Stack growth is multiplicative, for constant amortized cost.
+//
+// g->atomicstatus will be Grunning or Gscanrunning upon entry.
+// If the scheduler is trying to stop this g, then it will set preemptStop.
+//
+// This must be nowritebarrierrec because it can be called as part of
+// stack growth from other nowritebarrierrec functions, but the
+// compiler doesn't check this.
+//
+//go:nowritebarrierrec
+func newstack() {
+	thisg := getg()
+	// TODO: double check all gp. shouldn't be getg().
+	if thisg.m.morebuf.g.ptr().stackguard0 == stackFork {
+		throw("stack growth after fork")
+	}
+	if thisg.m.morebuf.g.ptr() != thisg.m.curg {
+		print("runtime: newstack called from g=", hex(thisg.m.morebuf.g), "\n"+"\tm=", thisg.m, " m->curg=", thisg.m.curg, " m->g0=", thisg.m.g0, " m->gsignal=", thisg.m.gsignal, "\n")
+		morebuf := thisg.m.morebuf
+		traceback(morebuf.pc, morebuf.sp, morebuf.lr, morebuf.g.ptr())
+		throw("runtime: wrong goroutine in newstack")
+	}
+
+	gp := thisg.m.curg
+
+	if thisg.m.curg.throwsplit {
+		// Update syscallsp, syscallpc in case traceback uses them.
+		morebuf := thisg.m.morebuf
+		gp.syscallsp = morebuf.sp
+		gp.syscallpc = morebuf.pc
+		pcname, pcoff := "(unknown)", uintptr(0)
+		f := findfunc(gp.sched.pc)
+		if f.valid() {
+			pcname = funcname(f)
+			pcoff = gp.sched.pc - f.entry()
+		}
+		print("runtime: newstack at ", pcname, "+", hex(pcoff),
+			" sp=", hex(gp.sched.sp), " stack=[", hex(gp.stack.lo), ", ", hex(gp.stack.hi), "]\n",
+			"\tmorebuf={pc:", hex(morebuf.pc), " sp:", hex(morebuf.sp), " lr:", hex(morebuf.lr), "}\n",
+			"\tsched={pc:", hex(gp.sched.pc), " sp:", hex(gp.sched.sp), " lr:", hex(gp.sched.lr), " ctxt:", gp.sched.ctxt, "}\n")
+
+		thisg.m.traceback = 2 // Include runtime frames
+		traceback(morebuf.pc, morebuf.sp, morebuf.lr, gp)
+		throw("runtime: stack split at bad time")
+	}
+
+	morebuf := thisg.m.morebuf
+	thisg.m.morebuf.pc = 0
+	thisg.m.morebuf.lr = 0
+	thisg.m.morebuf.sp = 0
+	thisg.m.morebuf.g = 0
+
+	// NOTE: stackguard0 may change underfoot, if another thread
+	// is about to try to preempt gp. Read it just once and use that same
+	// value now and below.
+	stackguard0 := atomic.Loaduintptr(&gp.stackguard0)
+
+	// Be conservative about where we preempt.
+	// We are interested in preempting user Go code, not runtime code.
+	// If we're holding locks, mallocing, or preemption is disabled, don't
+	// preempt.
+	// This check is very early in newstack so that even the status change
+	// from Grunning to Gwaiting and back doesn't happen in this case.
+	// That status change by itself can be viewed as a small preemption,
+	// because the GC might change Gwaiting to Gscanwaiting, and then
+	// this goroutine has to wait for the GC to finish before continuing.
+	// If the GC is in some way dependent on this goroutine (for example,
+	// it needs a lock held by the goroutine), that small preemption turns
+	// into a real deadlock.
+	preempt := stackguard0 == stackPreempt
+	if preempt {
+		if !canPreemptM(thisg.m) {
+			// Let the goroutine keep running for now.
+			// gp->preempt is set, so it will be preempted next time.
+			gp.stackguard0 = gp.stack.lo + _StackGuard
+			gogo(&gp.sched) // never return
+		}
+	}
+
+	if gp.stack.lo == 0 {
+		throw("missing stack in newstack")
+	}
+	sp := gp.sched.sp
+	if goarch.ArchFamily == goarch.AMD64 || goarch.ArchFamily == goarch.I386 || goarch.ArchFamily == goarch.WASM {
+		// The call to morestack cost a word.
+		sp -= goarch.PtrSize
+	}
+	if stackDebug >= 1 || sp < gp.stack.lo {
+		print("runtime: newstack sp=", hex(sp), " stack=[", hex(gp.stack.lo), ", ", hex(gp.stack.hi), "]\n",
+			"\tmorebuf={pc:", hex(morebuf.pc), " sp:", hex(morebuf.sp), " lr:", hex(morebuf.lr), "}\n",
+			"\tsched={pc:", hex(gp.sched.pc), " sp:", hex(gp.sched.sp), " lr:", hex(gp.sched.lr), " ctxt:", gp.sched.ctxt, "}\n")
+	}
+	if sp < gp.stack.lo {
+		print("runtime: gp=", gp, ", goid=", gp.goid, ", gp->status=", hex(readgstatus(gp)), "\n ")
+		print("runtime: split stack overflow: ", hex(sp), " < ", hex(gp.stack.lo), "\n")
+		throw("runtime: split stack overflow")
+	}
+
+	if preempt {
+		if gp == thisg.m.g0 {
+			throw("runtime: preempt g0")
+		}
+		if thisg.m.p == 0 && thisg.m.locks == 0 {
+			throw("runtime: g is running but p is not")
+		}
+
+		if gp.preemptShrink {
+			// We're at a synchronous safe point now, so
+			// do the pending stack shrink.
+			gp.preemptShrink = false
+			shrinkstack(gp)
+		}
+
+		if gp.preemptStop {
+			preemptPark(gp) // never returns
+		}
+
+		// Act like goroutine called runtime.Gosched.
+		gopreempt_m(gp) // never return
+	}
+
+	// Allocate a bigger segment and move the stack.
+	oldsize := gp.stack.hi - gp.stack.lo
+	newsize := oldsize * 2
+
+	// Make sure we grow at least as much as needed to fit the new frame.
+	// (This is just an optimization - the caller of morestack will
+	// recheck the bounds on return.)
+	if f := findfunc(gp.sched.pc); f.valid() {
+		max := uintptr(funcMaxSPDelta(f))
+		needed := max + _StackGuard
+		used := gp.stack.hi - gp.sched.sp
+		for newsize-used < needed {
+			newsize *= 2
+		}
+	}
+
+	if stackguard0 == stackForceMove {
+		// Forced stack movement used for debugging.
+		// Don't double the stack (or we may quickly run out
+		// if this is done repeatedly).
+		newsize = oldsize
+	}
+
+	if newsize > maxstacksize || newsize > maxstackceiling {
+		if maxstacksize < maxstackceiling {
+			print("runtime: goroutine stack exceeds ", maxstacksize, "-byte limit\n")
+		} else {
+			print("runtime: goroutine stack exceeds ", maxstackceiling, "-byte limit\n")
+		}
+		print("runtime: sp=", hex(sp), " stack=[", hex(gp.stack.lo), ", ", hex(gp.stack.hi), "]\n")
+		throw("stack overflow")
+	}
+
+	// The goroutine must be executing in order to call newstack,
+	// so it must be Grunning (or Gscanrunning).
+	casgstatus(gp, _Grunning, _Gcopystack)
+
+	// The concurrent GC will not scan the stack while we are doing the copy since
+	// the gp is in a Gcopystack status.
+	copystack(gp, newsize)
+	if stackDebug >= 1 {
+		print("stack grow done\n")
+	}
+	casgstatus(gp, _Gcopystack, _Grunning)
+	gogo(&gp.sched)
+}
+
+//go:nosplit
+func nilfunc() {
+	*(*uint8)(nil) = 0
+}
+
+// adjust Gobuf as if it executed a call to fn
+// and then stopped before the first instruction in fn.
+func gostartcallfn(gobuf *gobuf, fv *funcval) {
+	var fn unsafe.Pointer
+	if fv != nil {
+		fn = unsafe.Pointer(fv.fn)
+	} else {
+		fn = unsafe.Pointer(abi.FuncPCABIInternal(nilfunc))
+	}
+	gostartcall(gobuf, fn, unsafe.Pointer(fv))
+}
+
+// isShrinkStackSafe returns whether it's safe to attempt to shrink
+// gp's stack. Shrinking the stack is only safe when we have precise
+// pointer maps for all frames on the stack.
+func isShrinkStackSafe(gp *g) bool {
+	// We can't copy the stack if we're in a syscall.
+	// The syscall might have pointers into the stack and
+	// often we don't have precise pointer maps for the innermost
+	// frames.
+	//
+	// We also can't copy the stack if we're at an asynchronous
+	// safe-point because we don't have precise pointer maps for
+	// all frames.
+	//
+	// We also can't *shrink* the stack in the window between the
+	// goroutine calling gopark to park on a channel and
+	// gp.activeStackChans being set.
+	return gp.syscallsp == 0 && !gp.asyncSafePoint && atomic.Load8(&gp.parkingOnChan) == 0
+}
+
+// Maybe shrink the stack being used by gp.
+//
+// gp must be stopped and we must own its stack. It may be in
+// _Grunning, but only if this is our own user G.
+func shrinkstack(gp *g) {
+	if gp.stack.lo == 0 {
+		throw("missing stack in shrinkstack")
+	}
+	if s := readgstatus(gp); s&_Gscan == 0 {
+		// We don't own the stack via _Gscan. We could still
+		// own it if this is our own user G and we're on the
+		// system stack.
+		if !(gp == getg().m.curg && getg() != getg().m.curg && s == _Grunning) {
+			// We don't own the stack.
+			throw("bad status in shrinkstack")
+		}
+	}
+	if !isShrinkStackSafe(gp) {
+		throw("shrinkstack at bad time")
+	}
+	// Check for self-shrinks while in a libcall. These may have
+	// pointers into the stack disguised as uintptrs, but these
+	// code paths should all be nosplit.
+	if gp == getg().m.curg && gp.m.libcallsp != 0 {
+		throw("shrinking stack in libcall")
+	}
+
+	if debug.gcshrinkstackoff > 0 {
+		return
+	}
+	f := findfunc(gp.startpc)
+	if f.valid() && f.funcID == funcID_gcBgMarkWorker {
+		// We're not allowed to shrink the gcBgMarkWorker
+		// stack (see gcBgMarkWorker for explanation).
+		return
+	}
+
+	oldsize := gp.stack.hi - gp.stack.lo
+	newsize := oldsize / 2
+	// Don't shrink the allocation below the minimum-sized stack
+	// allocation.
+	if newsize < _FixedStack {
+		return
+	}
+	// Compute how much of the stack is currently in use and only
+	// shrink the stack if gp is using less than a quarter of its
+	// current stack. The currently used stack includes everything
+	// down to the SP plus the stack guard space that ensures
+	// there's room for nosplit functions.
+	avail := gp.stack.hi - gp.stack.lo
+	if used := gp.stack.hi - gp.sched.sp + _StackLimit; used >= avail/4 {
+		return
+	}
+
+	if stackDebug > 0 {
+		print("shrinking stack ", oldsize, "->", newsize, "\n")
+	}
+
+	copystack(gp, newsize)
+}
+
+// freeStackSpans frees unused stack spans at the end of GC.
+func freeStackSpans() {
+	// Scan stack pools for empty stack spans.
+	for order := range stackpool {
+		lock(&stackpool[order].item.mu)
+		list := &stackpool[order].item.span
+		for s := list.first; s != nil; {
+			next := s.next
+			if s.allocCount == 0 {
+				list.remove(s)
+				s.manualFreeList = 0
+				osStackFree(s)
+				mheap_.freeManual(s, spanAllocStack)
+			}
+			s = next
+		}
+		unlock(&stackpool[order].item.mu)
+	}
+
+	// Free large stack spans.
+	lock(&stackLarge.lock)
+	for i := range stackLarge.free {
+		for s := stackLarge.free[i].first; s != nil; {
+			next := s.next
+			stackLarge.free[i].remove(s)
+			osStackFree(s)
+			mheap_.freeManual(s, spanAllocStack)
+			s = next
+		}
+	}
+	unlock(&stackLarge.lock)
+}
+
+// getStackMap returns the locals and arguments live pointer maps, and
+// stack object list for frame.
+func getStackMap(frame *stkframe, cache *pcvalueCache, debug bool) (locals, args bitvector, objs []stackObjectRecord) {
+	targetpc := frame.continpc
+	if targetpc == 0 {
+		// Frame is dead. Return empty bitvectors.
+		return
+	}
+
+	f := frame.fn
+	pcdata := int32(-1)
+	if targetpc != f.entry() {
+		// Back up to the CALL. If we're at the function entry
+		// point, we want to use the entry map (-1), even if
+		// the first instruction of the function changes the
+		// stack map.
+		targetpc--
+		pcdata = pcdatavalue(f, _PCDATA_StackMapIndex, targetpc, cache)
+	}
+	if pcdata == -1 {
+		// We do not have a valid pcdata value but there might be a
+		// stackmap for this function. It is likely that we are looking
+		// at the function prologue, assume so and hope for the best.
+		pcdata = 0
+	}
+
+	// Local variables.
+	size := frame.varp - frame.sp
+	var minsize uintptr
+	switch goarch.ArchFamily {
+	case goarch.ARM64:
+		minsize = sys.StackAlign
+	default:
+		minsize = sys.MinFrameSize
+	}
+	if size > minsize {
+		stackid := pcdata
+		stkmap := (*stackmap)(funcdata(f, _FUNCDATA_LocalsPointerMaps))
+		if stkmap == nil || stkmap.n <= 0 {
+			print("runtime: frame ", funcname(f), " untyped locals ", hex(frame.varp-size), "+", hex(size), "\n")
+			throw("missing stackmap")
+		}
+		// If nbit == 0, there's no work to do.
+		if stkmap.nbit > 0 {
+			if stackid < 0 || stackid >= stkmap.n {
+				// don't know where we are
+				print("runtime: pcdata is ", stackid, " and ", stkmap.n, " locals stack map entries for ", funcname(f), " (targetpc=", hex(targetpc), ")\n")
+				throw("bad symbol table")
+			}
+			locals = stackmapdata(stkmap, stackid)
+			if stackDebug >= 3 && debug {
+				print("      locals ", stackid, "/", stkmap.n, " ", locals.n, " words ", locals.bytedata, "\n")
+			}
+		} else if stackDebug >= 3 && debug {
+			print("      no locals to adjust\n")
+		}
+	}
+
+	// Arguments.
+	if frame.arglen > 0 {
+		if frame.argmap != nil {
+			// argmap is set when the function is reflect.makeFuncStub or reflect.methodValueCall.
+			// In this case, arglen specifies how much of the args section is actually live.
+			// (It could be either all the args + results, or just the args.)
+			args = *frame.argmap
+			n := int32(frame.arglen / goarch.PtrSize)
+			if n < args.n {
+				args.n = n // Don't use more of the arguments than arglen.
+			}
+		} else {
+			stackmap := (*stackmap)(funcdata(f, _FUNCDATA_ArgsPointerMaps))
+			if stackmap == nil || stackmap.n <= 0 {
+				print("runtime: frame ", funcname(f), " untyped args ", hex(frame.argp), "+", hex(frame.arglen), "\n")
+				throw("missing stackmap")
+			}
+			if pcdata < 0 || pcdata >= stackmap.n {
+				// don't know where we are
+				print("runtime: pcdata is ", pcdata, " and ", stackmap.n, " args stack map entries for ", funcname(f), " (targetpc=", hex(targetpc), ")\n")
+				throw("bad symbol table")
+			}
+			if stackmap.nbit > 0 {
+				args = stackmapdata(stackmap, pcdata)
+			}
+		}
+	}
+
+	// stack objects.
+	if (GOARCH == "amd64" || GOARCH == "arm64" || GOARCH == "ppc64" || GOARCH == "ppc64le" || GOARCH == "riscv64") &&
+		unsafe.Sizeof(abi.RegArgs{}) > 0 && frame.argmap != nil {
+		// argmap is set when the function is reflect.makeFuncStub or reflect.methodValueCall.
+		// We don't actually use argmap in this case, but we need to fake the stack object
+		// record for these frames which contain an internal/abi.RegArgs at a hard-coded offset.
+		// This offset matches the assembly code on amd64 and arm64.
+		objs = methodValueCallFrameObjs[:]
+	} else {
+		p := funcdata(f, _FUNCDATA_StackObjects)
+		if p != nil {
+			n := *(*uintptr)(p)
+			p = add(p, goarch.PtrSize)
+			r0 := (*stackObjectRecord)(noescape(p))
+			objs = unsafe.Slice(r0, int(n))
+			// Note: the noescape above is needed to keep
+			// getStackMap from "leaking param content:
+			// frame".  That leak propagates up to getgcmask, then
+			// GCMask, then verifyGCInfo, which converts the stack
+			// gcinfo tests into heap gcinfo tests :(
+		}
+	}
+
+	return
+}
+
+var methodValueCallFrameObjs [1]stackObjectRecord // initialized in stackobjectinit
+
+func stkobjinit() {
+	var abiRegArgsEface any = abi.RegArgs{}
+	abiRegArgsType := efaceOf(&abiRegArgsEface)._type
+	if abiRegArgsType.kind&kindGCProg != 0 {
+		throw("abiRegArgsType needs GC Prog, update methodValueCallFrameObjs")
+	}
+	// Set methodValueCallFrameObjs[0].gcdataoff so that
+	// stackObjectRecord.gcdata() will work correctly with it.
+	ptr := uintptr(unsafe.Pointer(&methodValueCallFrameObjs[0]))
+	var mod *moduledata
+	for datap := &firstmoduledata; datap != nil; datap = datap.next {
+		if datap.gofunc <= ptr && ptr < datap.end {
+			mod = datap
+			break
+		}
+	}
+	if mod == nil {
+		throw("methodValueCallFrameObjs is not in a module")
+	}
+	methodValueCallFrameObjs[0] = stackObjectRecord{
+		off:       -int32(alignUp(abiRegArgsType.size, 8)), // It's always the highest address local.
+		size:      int32(abiRegArgsType.size),
+		_ptrdata:  int32(abiRegArgsType.ptrdata),
+		gcdataoff: uint32(uintptr(unsafe.Pointer(abiRegArgsType.gcdata)) - mod.rodata),
+	}
+}
+
+// A stackObjectRecord is generated by the compiler for each stack object in a stack frame.
+// This record must match the generator code in cmd/compile/internal/liveness/plive.go:emitStackObjects.
+type stackObjectRecord struct {
+	// offset in frame
+	// if negative, offset from varp
+	// if non-negative, offset from argp
+	off       int32
+	size      int32
+	_ptrdata  int32  // ptrdata, or -ptrdata is GC prog is used
+	gcdataoff uint32 // offset to gcdata from moduledata.rodata
+}
+
+func (r *stackObjectRecord) useGCProg() bool {
+	return r._ptrdata < 0
+}
+
+func (r *stackObjectRecord) ptrdata() uintptr {
+	x := r._ptrdata
+	if x < 0 {
+		return uintptr(-x)
+	}
+	return uintptr(x)
+}
+
+// gcdata returns pointer map or GC prog of the type.
+func (r *stackObjectRecord) gcdata() *byte {
+	ptr := uintptr(unsafe.Pointer(r))
+	var mod *moduledata
+	for datap := &firstmoduledata; datap != nil; datap = datap.next {
+		if datap.gofunc <= ptr && ptr < datap.end {
+			mod = datap
+			break
+		}
+	}
+	// If you get a panic here due to a nil mod,
+	// you may have made a copy of a stackObjectRecord.
+	// You must use the original pointer.
+	res := mod.rodata + uintptr(r.gcdataoff)
+	return (*byte)(unsafe.Pointer(res))
+}
+
+// This is exported as ABI0 via linkname so obj can call it.
+//
+//go:nosplit
+//go:linkname morestackc
+func morestackc() {
+	throw("attempt to execute system stack code on user stack")
+}
+
+// startingStackSize is the amount of stack that new goroutines start with.
+// It is a power of 2, and between _FixedStack and maxstacksize, inclusive.
+// startingStackSize is updated every GC by tracking the average size of
+// stacks scanned during the GC.
+var startingStackSize uint32 = _FixedStack
+
+func gcComputeStartingStackSize() {
+	if debug.adaptivestackstart == 0 {
+		return
+	}
+	// For details, see the design doc at
+	// https://docs.google.com/document/d/1YDlGIdVTPnmUiTAavlZxBI1d9pwGQgZT7IKFKlIXohQ/edit?usp=sharing
+	// The basic algorithm is to track the average size of stacks
+	// and start goroutines with stack equal to that average size.
+	// Starting at the average size uses at most 2x the space that
+	// an ideal algorithm would have used.
+	// This is just a heuristic to avoid excessive stack growth work
+	// early in a goroutine's lifetime. See issue 18138. Stacks that
+	// are allocated too small can still grow, and stacks allocated
+	// too large can still shrink.
+	var scannedStackSize uint64
+	var scannedStacks uint64
+	for _, p := range allp {
+		scannedStackSize += p.scannedStackSize
+		scannedStacks += p.scannedStacks
+		// Reset for next time
+		p.scannedStackSize = 0
+		p.scannedStacks = 0
+	}
+	if scannedStacks == 0 {
+		startingStackSize = _FixedStack
+		return
+	}
+	avg := scannedStackSize/scannedStacks + _StackGuard
+	// Note: we add _StackGuard to ensure that a goroutine that
+	// uses the average space will not trigger a growth.
+	if avg > uint64(maxstacksize) {
+		avg = uint64(maxstacksize)
+	}
+	if avg < _FixedStack {
+		avg = _FixedStack
+	}
+	// Note: maxstacksize fits in 30 bits, so avg also does.
+	startingStackSize = uint32(round2(int32(avg)))
+}
diff --git a/contrib/go/_std_1.19/src/runtime/string.go b/contrib/go/_std_1.19/src/runtime/string.go
new file mode 100644
index 0000000000..359a5658c5
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/string.go
@@ -0,0 +1,589 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"internal/abi"
+	"internal/bytealg"
+	"internal/goarch"
+	"unsafe"
+)
+
+// The constant is known to the compiler.
+// There is no fundamental theory behind this number.
+const tmpStringBufSize = 32
+
+type tmpBuf [tmpStringBufSize]byte
+
+// concatstrings implements a Go string concatenation x+y+z+...
+// The operands are passed in the slice a.
+// If buf != nil, the compiler has determined that the result does not
+// escape the calling function, so the string data can be stored in buf
+// if small enough.
+func concatstrings(buf *tmpBuf, a []string) string {
+	idx := 0
+	l := 0
+	count := 0
+	for i, x := range a {
+		n := len(x)
+		if n == 0 {
+			continue
+		}
+		if l+n < l {
+			throw("string concatenation too long")
+		}
+		l += n
+		count++
+		idx = i
+	}
+	if count == 0 {
+		return ""
+	}
+
+	// If there is just one string and either it is not on the stack
+	// or our result does not escape the calling frame (buf != nil),
+	// then we can return that string directly.
+	if count == 1 && (buf != nil || !stringDataOnStack(a[idx])) {
+		return a[idx]
+	}
+	s, b := rawstringtmp(buf, l)
+	for _, x := range a {
+		copy(b, x)
+		b = b[len(x):]
+	}
+	return s
+}
+
+func concatstring2(buf *tmpBuf, a0, a1 string) string {
+	return concatstrings(buf, []string{a0, a1})
+}
+
+func concatstring3(buf *tmpBuf, a0, a1, a2 string) string {
+	return concatstrings(buf, []string{a0, a1, a2})
+}
+
+func concatstring4(buf *tmpBuf, a0, a1, a2, a3 string) string {
+	return concatstrings(buf, []string{a0, a1, a2, a3})
+}
+
+func concatstring5(buf *tmpBuf, a0, a1, a2, a3, a4 string) string {
+	return concatstrings(buf, []string{a0, a1, a2, a3, a4})
+}
+
+// slicebytetostring converts a byte slice to a string.
+// It is inserted by the compiler into generated code.
+// ptr is a pointer to the first element of the slice;
+// n is the length of the slice.
+// Buf is a fixed-size buffer for the result,
+// it is not nil if the result does not escape.
+func slicebytetostring(buf *tmpBuf, ptr *byte, n int) (str string) {
+	if n == 0 {
+		// Turns out to be a relatively common case.
+		// Consider that you want to parse out data between parens in "foo()bar",
+		// you find the indices and convert the subslice to string.
+		return ""
+	}
+	if raceenabled {
+		racereadrangepc(unsafe.Pointer(ptr),
+			uintptr(n),
+			getcallerpc(),
+			abi.FuncPCABIInternal(slicebytetostring))
+	}
+	if msanenabled {
+		msanread(unsafe.Pointer(ptr), uintptr(n))
+	}
+	if asanenabled {
+		asanread(unsafe.Pointer(ptr), uintptr(n))
+	}
+	if n == 1 {
+		p := unsafe.Pointer(&staticuint64s[*ptr])
+		if goarch.BigEndian {
+			p = add(p, 7)
+		}
+		stringStructOf(&str).str = p
+		stringStructOf(&str).len = 1
+		return
+	}
+
+	var p unsafe.Pointer
+	if buf != nil && n <= len(buf) {
+		p = unsafe.Pointer(buf)
+	} else {
+		p = mallocgc(uintptr(n), nil, false)
+	}
+	stringStructOf(&str).str = p
+	stringStructOf(&str).len = n
+	memmove(p, unsafe.Pointer(ptr), uintptr(n))
+	return
+}
+
+// stringDataOnStack reports whether the string's data is
+// stored on the current goroutine's stack.
+func stringDataOnStack(s string) bool {
+	ptr := uintptr(stringStructOf(&s).str)
+	stk := getg().stack
+	return stk.lo <= ptr && ptr < stk.hi
+}
+
+func rawstringtmp(buf *tmpBuf, l int) (s string, b []byte) {
+	if buf != nil && l <= len(buf) {
+		b = buf[:l]
+		s = slicebytetostringtmp(&b[0], len(b))
+	} else {
+		s, b = rawstring(l)
+	}
+	return
+}
+
+// slicebytetostringtmp returns a "string" referring to the actual []byte bytes.
+//
+// Callers need to ensure that the returned string will not be used after
+// the calling goroutine modifies the original slice or synchronizes with
+// another goroutine.
+//
+// The function is only called when instrumenting
+// and otherwise intrinsified by the compiler.
+//
+// Some internal compiler optimizations use this function.
+//   - Used for m[T1{... Tn{..., string(k), ...} ...}] and m[string(k)]
+//     where k is []byte, T1 to Tn is a nesting of struct and array literals.
+//   - Used for "<"+string(b)+">" concatenation where b is []byte.
+//   - Used for string(b)=="foo" comparison where b is []byte.
+func slicebytetostringtmp(ptr *byte, n int) (str string) {
+	if raceenabled && n > 0 {
+		racereadrangepc(unsafe.Pointer(ptr),
+			uintptr(n),
+			getcallerpc(),
+			abi.FuncPCABIInternal(slicebytetostringtmp))
+	}
+	if msanenabled && n > 0 {
+		msanread(unsafe.Pointer(ptr), uintptr(n))
+	}
+	if asanenabled && n > 0 {
+		asanread(unsafe.Pointer(ptr), uintptr(n))
+	}
+	stringStructOf(&str).str = unsafe.Pointer(ptr)
+	stringStructOf(&str).len = n
+	return
+}
+
+func stringtoslicebyte(buf *tmpBuf, s string) []byte {
+	var b []byte
+	if buf != nil && len(s) <= len(buf) {
+		*buf = tmpBuf{}
+		b = buf[:len(s)]
+	} else {
+		b = rawbyteslice(len(s))
+	}
+	copy(b, s)
+	return b
+}
+
+func stringtoslicerune(buf *[tmpStringBufSize]rune, s string) []rune {
+	// two passes.
+	// unlike slicerunetostring, no race because strings are immutable.
+	n := 0
+	for range s {
+		n++
+	}
+
+	var a []rune
+	if buf != nil && n <= len(buf) {
+		*buf = [tmpStringBufSize]rune{}
+		a = buf[:n]
+	} else {
+		a = rawruneslice(n)
+	}
+
+	n = 0
+	for _, r := range s {
+		a[n] = r
+		n++
+	}
+	return a
+}
+
+func slicerunetostring(buf *tmpBuf, a []rune) string {
+	if raceenabled && len(a) > 0 {
+		racereadrangepc(unsafe.Pointer(&a[0]),
+			uintptr(len(a))*unsafe.Sizeof(a[0]),
+			getcallerpc(),
+			abi.FuncPCABIInternal(slicerunetostring))
+	}
+	if msanenabled && len(a) > 0 {
+		msanread(unsafe.Pointer(&a[0]), uintptr(len(a))*unsafe.Sizeof(a[0]))
+	}
+	if asanenabled && len(a) > 0 {
+		asanread(unsafe.Pointer(&a[0]), uintptr(len(a))*unsafe.Sizeof(a[0]))
+	}
+	var dum [4]byte
+	size1 := 0
+	for _, r := range a {
+		size1 += encoderune(dum[:], r)
+	}
+	s, b := rawstringtmp(buf, size1+3)
+	size2 := 0
+	for _, r := range a {
+		// check for race
+		if size2 >= size1 {
+			break
+		}
+		size2 += encoderune(b[size2:], r)
+	}
+	return s[:size2]
+}
+
+type stringStruct struct {
+	str unsafe.Pointer
+	len int
+}
+
+// Variant with *byte pointer type for DWARF debugging.
+type stringStructDWARF struct {
+	str *byte
+	len int
+}
+
+func stringStructOf(sp *string) *stringStruct {
+	return (*stringStruct)(unsafe.Pointer(sp))
+}
+
+func intstring(buf *[4]byte, v int64) (s string) {
+	var b []byte
+	if buf != nil {
+		b = buf[:]
+		s = slicebytetostringtmp(&b[0], len(b))
+	} else {
+		s, b = rawstring(4)
+	}
+	if int64(rune(v)) != v {
+		v = runeError
+	}
+	n := encoderune(b, rune(v))
+	return s[:n]
+}
+
+// rawstring allocates storage for a new string. The returned
+// string and byte slice both refer to the same storage.
+// The storage is not zeroed. Callers should use
+// b to set the string contents and then drop b.
+func rawstring(size int) (s string, b []byte) {
+	p := mallocgc(uintptr(size), nil, false)
+
+	stringStructOf(&s).str = p
+	stringStructOf(&s).len = size
+
+	*(*slice)(unsafe.Pointer(&b)) = slice{p, size, size}
+
+	return
+}
+
+// rawbyteslice allocates a new byte slice. The byte slice is not zeroed.
+func rawbyteslice(size int) (b []byte) {
+	cap := roundupsize(uintptr(size))
+	p := mallocgc(cap, nil, false)
+	if cap != uintptr(size) {
+		memclrNoHeapPointers(add(p, uintptr(size)), cap-uintptr(size))
+	}
+
+	*(*slice)(unsafe.Pointer(&b)) = slice{p, size, int(cap)}
+	return
+}
+
+// rawruneslice allocates a new rune slice. The rune slice is not zeroed.
+func rawruneslice(size int) (b []rune) {
+	if uintptr(size) > maxAlloc/4 {
+		throw("out of memory")
+	}
+	mem := roundupsize(uintptr(size) * 4)
+	p := mallocgc(mem, nil, false)
+	if mem != uintptr(size)*4 {
+		memclrNoHeapPointers(add(p, uintptr(size)*4), mem-uintptr(size)*4)
+	}
+
+	*(*slice)(unsafe.Pointer(&b)) = slice{p, size, int(mem / 4)}
+	return
+}
+
+// used by cmd/cgo
+func gobytes(p *byte, n int) (b []byte) {
+	if n == 0 {
+		return make([]byte, 0)
+	}
+
+	if n < 0 || uintptr(n) > maxAlloc {
+		panic(errorString("gobytes: length out of range"))
+	}
+
+	bp := mallocgc(uintptr(n), nil, false)
+	memmove(bp, unsafe.Pointer(p), uintptr(n))
+
+	*(*slice)(unsafe.Pointer(&b)) = slice{bp, n, n}
+	return
+}
+
+// This is exported via linkname to assembly in syscall (for Plan9).
+//
+//go:linkname gostring
+func gostring(p *byte) string {
+	l := findnull(p)
+	if l == 0 {
+		return ""
+	}
+	s, b := rawstring(l)
+	memmove(unsafe.Pointer(&b[0]), unsafe.Pointer(p), uintptr(l))
+	return s
+}
+
+func gostringn(p *byte, l int) string {
+	if l == 0 {
+		return ""
+	}
+	s, b := rawstring(l)
+	memmove(unsafe.Pointer(&b[0]), unsafe.Pointer(p), uintptr(l))
+	return s
+}
+
+func hasPrefix(s, prefix string) bool {
+	return len(s) >= len(prefix) && s[:len(prefix)] == prefix
+}
+
+const (
+	maxUint64 = ^uint64(0)
+	maxInt64  = int64(maxUint64 >> 1)
+)
+
+// atoi64 parses an int64 from a string s.
+// The bool result reports whether s is a number
+// representable by a value of type int64.
+func atoi64(s string) (int64, bool) {
+	if s == "" {
+		return 0, false
+	}
+
+	neg := false
+	if s[0] == '-' {
+		neg = true
+		s = s[1:]
+	}
+
+	un := uint64(0)
+	for i := 0; i < len(s); i++ {
+		c := s[i]
+		if c < '0' || c > '9' {
+			return 0, false
+		}
+		if un > maxUint64/10 {
+			// overflow
+			return 0, false
+		}
+		un *= 10
+		un1 := un + uint64(c) - '0'
+		if un1 < un {
+			// overflow
+			return 0, false
+		}
+		un = un1
+	}
+
+	if !neg && un > uint64(maxInt64) {
+		return 0, false
+	}
+	if neg && un > uint64(maxInt64)+1 {
+		return 0, false
+	}
+
+	n := int64(un)
+	if neg {
+		n = -n
+	}
+
+	return n, true
+}
+
+// atoi is like atoi64 but for integers
+// that fit into an int.
+func atoi(s string) (int, bool) {
+	if n, ok := atoi64(s); n == int64(int(n)) {
+		return int(n), ok
+	}
+	return 0, false
+}
+
+// atoi32 is like atoi but for integers
+// that fit into an int32.
+func atoi32(s string) (int32, bool) {
+	if n, ok := atoi64(s); n == int64(int32(n)) {
+		return int32(n), ok
+	}
+	return 0, false
+}
+
+// parseByteCount parses a string that represents a count of bytes.
+//
+// s must match the following regular expression:
+//
+//	^[0-9]+(([KMGT]i)?B)?$
+//
+// In other words, an integer byte count with an optional unit
+// suffix. Acceptable suffixes include one of
+// - KiB, MiB, GiB, TiB which represent binary IEC/ISO 80000 units, or
+// - B, which just represents bytes.
+//
+// Returns an int64 because that's what its callers want and receive,
+// but the result is always non-negative.
+func parseByteCount(s string) (int64, bool) {
+	// The empty string is not valid.
+	if s == "" {
+		return 0, false
+	}
+	// Handle the easy non-suffix case.
+	last := s[len(s)-1]
+	if last >= '0' && last <= '9' {
+		n, ok := atoi64(s)
+		if !ok || n < 0 {
+			return 0, false
+		}
+		return n, ok
+	}
+	// Failing a trailing digit, this must always end in 'B'.
+	// Also at this point there must be at least one digit before
+	// that B.
+	if last != 'B' || len(s) < 2 {
+		return 0, false
+	}
+	// The one before that must always be a digit or 'i'.
+	if c := s[len(s)-2]; c >= '0' && c <= '9' {
+		// Trivial 'B' suffix.
+		n, ok := atoi64(s[:len(s)-1])
+		if !ok || n < 0 {
+			return 0, false
+		}
+		return n, ok
+	} else if c != 'i' {
+		return 0, false
+	}
+	// Finally, we need at least 4 characters now, for the unit
+	// prefix and at least one digit.
+	if len(s) < 4 {
+		return 0, false
+	}
+	power := 0
+	switch s[len(s)-3] {
+	case 'K':
+		power = 1
+	case 'M':
+		power = 2
+	case 'G':
+		power = 3
+	case 'T':
+		power = 4
+	default:
+		// Invalid suffix.
+		return 0, false
+	}
+	m := uint64(1)
+	for i := 0; i < power; i++ {
+		m *= 1024
+	}
+	n, ok := atoi64(s[:len(s)-3])
+	if !ok || n < 0 {
+		return 0, false
+	}
+	un := uint64(n)
+	if un > maxUint64/m {
+		// Overflow.
+		return 0, false
+	}
+	un *= m
+	if un > uint64(maxInt64) {
+		// Overflow.
+		return 0, false
+	}
+	return int64(un), true
+}
+
+//go:nosplit
+func findnull(s *byte) int {
+	if s == nil {
+		return 0
+	}
+
+	// Avoid IndexByteString on Plan 9 because it uses SSE instructions
+	// on x86 machines, and those are classified as floating point instructions,
+	// which are illegal in a note handler.
+	if GOOS == "plan9" {
+		p := (*[maxAlloc/2 - 1]byte)(unsafe.Pointer(s))
+		l := 0
+		for p[l] != 0 {
+			l++
+		}
+		return l
+	}
+
+	// pageSize is the unit we scan at a time looking for NULL.
+	// It must be the minimum page size for any architecture Go
+	// runs on. It's okay (just a minor performance loss) if the
+	// actual system page size is larger than this value.
+	const pageSize = 4096
+
+	offset := 0
+	ptr := unsafe.Pointer(s)
+	// IndexByteString uses wide reads, so we need to be careful
+	// with page boundaries. Call IndexByteString on
+	// [ptr, endOfPage) interval.
+	safeLen := int(pageSize - uintptr(ptr)%pageSize)
+
+	for {
+		t := *(*string)(unsafe.Pointer(&stringStruct{ptr, safeLen}))
+		// Check one page at a time.
+		if i := bytealg.IndexByteString(t, 0); i != -1 {
+			return offset + i
+		}
+		// Move to next page
+		ptr = unsafe.Pointer(uintptr(ptr) + uintptr(safeLen))
+		offset += safeLen
+		safeLen = pageSize
+	}
+}
+
+func findnullw(s *uint16) int {
+	if s == nil {
+		return 0
+	}
+	p := (*[maxAlloc/2/2 - 1]uint16)(unsafe.Pointer(s))
+	l := 0
+	for p[l] != 0 {
+		l++
+	}
+	return l
+}
+
+//go:nosplit
+func gostringnocopy(str *byte) string {
+	ss := stringStruct{str: unsafe.Pointer(str), len: findnull(str)}
+	s := *(*string)(unsafe.Pointer(&ss))
+	return s
+}
+
+func gostringw(strw *uint16) string {
+	var buf [8]byte
+	str := (*[maxAlloc/2/2 - 1]uint16)(unsafe.Pointer(strw))
+	n1 := 0
+	for i := 0; str[i] != 0; i++ {
+		n1 += encoderune(buf[:], rune(str[i]))
+	}
+	s, b := rawstring(n1 + 4)
+	n2 := 0
+	for i := 0; str[i] != 0; i++ {
+		// check for race
+		if n2 >= n1 {
+			break
+		}
+		n2 += encoderune(b[n2:], rune(str[i]))
+	}
+	b[n2] = 0 // for luck
+	return s[:n2]
+}
diff --git a/contrib/go/_std_1.19/src/runtime/stubs.go b/contrib/go/_std_1.19/src/runtime/stubs.go
new file mode 100644
index 0000000000..929f8fadca
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/stubs.go
@@ -0,0 +1,480 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"internal/abi"
+	"internal/goarch"
+	"runtime/internal/math"
+	"unsafe"
+)
+
+// Should be a built-in for unsafe.Pointer?
+//
+//go:nosplit
+func add(p unsafe.Pointer, x uintptr) unsafe.Pointer {
+	return unsafe.Pointer(uintptr(p) + x)
+}
+
+// getg returns the pointer to the current g.
+// The compiler rewrites calls to this function into instructions
+// that fetch the g directly (from TLS or from the dedicated register).
+func getg() *g
+
+// mcall switches from the g to the g0 stack and invokes fn(g),
+// where g is the goroutine that made the call.
+// mcall saves g's current PC/SP in g->sched so that it can be restored later.
+// It is up to fn to arrange for that later execution, typically by recording
+// g in a data structure, causing something to call ready(g) later.
+// mcall returns to the original goroutine g later, when g has been rescheduled.
+// fn must not return at all; typically it ends by calling schedule, to let the m
+// run other goroutines.
+//
+// mcall can only be called from g stacks (not g0, not gsignal).
+//
+// This must NOT be go:noescape: if fn is a stack-allocated closure,
+// fn puts g on a run queue, and g executes before fn returns, the
+// closure will be invalidated while it is still executing.
+func mcall(fn func(*g))
+
+// systemstack runs fn on a system stack.
+// If systemstack is called from the per-OS-thread (g0) stack, or
+// if systemstack is called from the signal handling (gsignal) stack,
+// systemstack calls fn directly and returns.
+// Otherwise, systemstack is being called from the limited stack
+// of an ordinary goroutine. In this case, systemstack switches
+// to the per-OS-thread stack, calls fn, and switches back.
+// It is common to use a func literal as the argument, in order
+// to share inputs and outputs with the code around the call
+// to system stack:
+//
+//	... set up y ...
+//	systemstack(func() {
+//		x = bigcall(y)
+//	})
+//	... use x ...
+//
+//go:noescape
+func systemstack(fn func())
+
+var badsystemstackMsg = "fatal: systemstack called from unexpected goroutine"
+
+//go:nosplit
+//go:nowritebarrierrec
+func badsystemstack() {
+	sp := stringStructOf(&badsystemstackMsg)
+	write(2, sp.str, int32(sp.len))
+}
+
+// memclrNoHeapPointers clears n bytes starting at ptr.
+//
+// Usually you should use typedmemclr. memclrNoHeapPointers should be
+// used only when the caller knows that *ptr contains no heap pointers
+// because either:
+//
+// *ptr is initialized memory and its type is pointer-free, or
+//
+// *ptr is uninitialized memory (e.g., memory that's being reused
+// for a new allocation) and hence contains only "junk".
+//
+// memclrNoHeapPointers ensures that if ptr is pointer-aligned, and n
+// is a multiple of the pointer size, then any pointer-aligned,
+// pointer-sized portion is cleared atomically. Despite the function
+// name, this is necessary because this function is the underlying
+// implementation of typedmemclr and memclrHasPointers. See the doc of
+// memmove for more details.
+//
+// The (CPU-specific) implementations of this function are in memclr_*.s.
+//
+//go:noescape
+func memclrNoHeapPointers(ptr unsafe.Pointer, n uintptr)
+
+//go:linkname reflect_memclrNoHeapPointers reflect.memclrNoHeapPointers
+func reflect_memclrNoHeapPointers(ptr unsafe.Pointer, n uintptr) {
+	memclrNoHeapPointers(ptr, n)
+}
+
+// memmove copies n bytes from "from" to "to".
+//
+// memmove ensures that any pointer in "from" is written to "to" with
+// an indivisible write, so that racy reads cannot observe a
+// half-written pointer. This is necessary to prevent the garbage
+// collector from observing invalid pointers, and differs from memmove
+// in unmanaged languages. However, memmove is only required to do
+// this if "from" and "to" may contain pointers, which can only be the
+// case if "from", "to", and "n" are all be word-aligned.
+//
+// Implementations are in memmove_*.s.
+//
+//go:noescape
+func memmove(to, from unsafe.Pointer, n uintptr)
+
+// Outside assembly calls memmove. Make sure it has ABI wrappers.
+//
+//go:linkname memmove
+
+//go:linkname reflect_memmove reflect.memmove
+func reflect_memmove(to, from unsafe.Pointer, n uintptr) {
+	memmove(to, from, n)
+}
+
+// exported value for testing
+const hashLoad = float32(loadFactorNum) / float32(loadFactorDen)
+
+//go:nosplit
+func fastrand() uint32 {
+	mp := getg().m
+	// Implement wyrand: https://github.com/wangyi-fudan/wyhash
+	// Only the platform that math.Mul64 can be lowered
+	// by the compiler should be in this list.
+	if goarch.IsAmd64|goarch.IsArm64|goarch.IsPpc64|
+		goarch.IsPpc64le|goarch.IsMips64|goarch.IsMips64le|
+		goarch.IsS390x|goarch.IsRiscv64 == 1 {
+		mp.fastrand += 0xa0761d6478bd642f
+		hi, lo := math.Mul64(mp.fastrand, mp.fastrand^0xe7037ed1a0b428db)
+		return uint32(hi ^ lo)
+	}
+
+	// Implement xorshift64+: 2 32-bit xorshift sequences added together.
+	// Shift triplet [17,7,16] was calculated as indicated in Marsaglia's
+	// Xorshift paper: https://www.jstatsoft.org/article/view/v008i14/xorshift.pdf
+	// This generator passes the SmallCrush suite, part of TestU01 framework:
+	// http://simul.iro.umontreal.ca/testu01/tu01.html
+	t := (*[2]uint32)(unsafe.Pointer(&mp.fastrand))
+	s1, s0 := t[0], t[1]
+	s1 ^= s1 << 17
+	s1 = s1 ^ s0 ^ s1>>7 ^ s0>>16
+	t[0], t[1] = s0, s1
+	return s0 + s1
+}
+
+//go:nosplit
+func fastrandn(n uint32) uint32 {
+	// This is similar to fastrand() % n, but faster.
+	// See https://lemire.me/blog/2016/06/27/a-fast-alternative-to-the-modulo-reduction/
+	return uint32(uint64(fastrand()) * uint64(n) >> 32)
+}
+
+func fastrand64() uint64 {
+	mp := getg().m
+	// Implement wyrand: https://github.com/wangyi-fudan/wyhash
+	// Only the platform that math.Mul64 can be lowered
+	// by the compiler should be in this list.
+	if goarch.IsAmd64|goarch.IsArm64|goarch.IsPpc64|
+		goarch.IsPpc64le|goarch.IsMips64|goarch.IsMips64le|
+		goarch.IsS390x|goarch.IsRiscv64 == 1 {
+		mp.fastrand += 0xa0761d6478bd642f
+		hi, lo := math.Mul64(mp.fastrand, mp.fastrand^0xe7037ed1a0b428db)
+		return hi ^ lo
+	}
+
+	// Implement xorshift64+: 2 32-bit xorshift sequences added together.
+	// Xorshift paper: https://www.jstatsoft.org/article/view/v008i14/xorshift.pdf
+	// This generator passes the SmallCrush suite, part of TestU01 framework:
+	// http://simul.iro.umontreal.ca/testu01/tu01.html
+	t := (*[2]uint32)(unsafe.Pointer(&mp.fastrand))
+	s1, s0 := t[0], t[1]
+	s1 ^= s1 << 17
+	s1 = s1 ^ s0 ^ s1>>7 ^ s0>>16
+	r := uint64(s0 + s1)
+
+	s0, s1 = s1, s0
+	s1 ^= s1 << 17
+	s1 = s1 ^ s0 ^ s1>>7 ^ s0>>16
+	r += uint64(s0+s1) << 32
+
+	t[0], t[1] = s0, s1
+	return r
+}
+
+func fastrandu() uint {
+	if goarch.PtrSize == 4 {
+		return uint(fastrand())
+	}
+	return uint(fastrand64())
+}
+
+//go:linkname sync_fastrandn sync.fastrandn
+func sync_fastrandn(n uint32) uint32 { return fastrandn(n) }
+
+//go:linkname net_fastrandu net.fastrandu
+func net_fastrandu() uint { return fastrandu() }
+
+//go:linkname os_fastrand os.fastrand
+func os_fastrand() uint32 { return fastrand() }
+
+// in internal/bytealg/equal_*.s
+//
+//go:noescape
+func memequal(a, b unsafe.Pointer, size uintptr) bool
+
+// noescape hides a pointer from escape analysis.  noescape is
+// the identity function but escape analysis doesn't think the
+// output depends on the input.  noescape is inlined and currently
+// compiles down to zero instructions.
+// USE CAREFULLY!
+//
+//go:nosplit
+func noescape(p unsafe.Pointer) unsafe.Pointer {
+	x := uintptr(p)
+	return unsafe.Pointer(x ^ 0)
+}
+
+// Not all cgocallback frames are actually cgocallback,
+// so not all have these arguments. Mark them uintptr so that the GC
+// does not misinterpret memory when the arguments are not present.
+// cgocallback is not called from Go, only from crosscall2.
+// This in turn calls cgocallbackg, which is where we'll find
+// pointer-declared arguments.
+func cgocallback(fn, frame, ctxt uintptr)
+
+func gogo(buf *gobuf)
+
+func asminit()
+func setg(gg *g)
+func breakpoint()
+
+// reflectcall calls fn with arguments described by stackArgs, stackArgsSize,
+// frameSize, and regArgs.
+//
+// Arguments passed on the stack and space for return values passed on the stack
+// must be laid out at the space pointed to by stackArgs (with total length
+// stackArgsSize) according to the ABI.
+//
+// stackRetOffset must be some value <= stackArgsSize that indicates the
+// offset within stackArgs where the return value space begins.
+//
+// frameSize is the total size of the argument frame at stackArgs and must
+// therefore be >= stackArgsSize. It must include additional space for spilling
+// register arguments for stack growth and preemption.
+//
+// TODO(mknyszek): Once we don't need the additional spill space, remove frameSize,
+// since frameSize will be redundant with stackArgsSize.
+//
+// Arguments passed in registers must be laid out in regArgs according to the ABI.
+// regArgs will hold any return values passed in registers after the call.
+//
+// reflectcall copies stack arguments from stackArgs to the goroutine stack, and
+// then copies back stackArgsSize-stackRetOffset bytes back to the return space
+// in stackArgs once fn has completed. It also "unspills" argument registers from
+// regArgs before calling fn, and spills them back into regArgs immediately
+// following the call to fn. If there are results being returned on the stack,
+// the caller should pass the argument frame type as stackArgsType so that
+// reflectcall can execute appropriate write barriers during the copy.
+//
+// reflectcall expects regArgs.ReturnIsPtr to be populated indicating which
+// registers on the return path will contain Go pointers. It will then store
+// these pointers in regArgs.Ptrs such that they are visible to the GC.
+//
+// Package reflect passes a frame type. In package runtime, there is only
+// one call that copies results back, in callbackWrap in syscall_windows.go, and it
+// does NOT pass a frame type, meaning there are no write barriers invoked. See that
+// call site for justification.
+//
+// Package reflect accesses this symbol through a linkname.
+//
+// Arguments passed through to reflectcall do not escape. The type is used
+// only in a very limited callee of reflectcall, the stackArgs are copied, and
+// regArgs is only used in the reflectcall frame.
+//
+//go:noescape
+func reflectcall(stackArgsType *_type, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+
+func procyield(cycles uint32)
+
+type neverCallThisFunction struct{}
+
+// goexit is the return stub at the top of every goroutine call stack.
+// Each goroutine stack is constructed as if goexit called the
+// goroutine's entry point function, so that when the entry point
+// function returns, it will return to goexit, which will call goexit1
+// to perform the actual exit.
+//
+// This function must never be called directly. Call goexit1 instead.
+// gentraceback assumes that goexit terminates the stack. A direct
+// call on the stack will cause gentraceback to stop walking the stack
+// prematurely and if there is leftover state it may panic.
+func goexit(neverCallThisFunction)
+
+// publicationBarrier performs a store/store barrier (a "publication"
+// or "export" barrier). Some form of synchronization is required
+// between initializing an object and making that object accessible to
+// another processor. Without synchronization, the initialization
+// writes and the "publication" write may be reordered, allowing the
+// other processor to follow the pointer and observe an uninitialized
+// object. In general, higher-level synchronization should be used,
+// such as locking or an atomic pointer write. publicationBarrier is
+// for when those aren't an option, such as in the implementation of
+// the memory manager.
+//
+// There's no corresponding barrier for the read side because the read
+// side naturally has a data dependency order. All architectures that
+// Go supports or seems likely to ever support automatically enforce
+// data dependency ordering.
+func publicationBarrier()
+
+// getcallerpc returns the program counter (PC) of its caller's caller.
+// getcallersp returns the stack pointer (SP) of its caller's caller.
+// The implementation may be a compiler intrinsic; there is not
+// necessarily code implementing this on every platform.
+//
+// For example:
+//
+//	func f(arg1, arg2, arg3 int) {
+//		pc := getcallerpc()
+//		sp := getcallersp()
+//	}
+//
+// These two lines find the PC and SP immediately following
+// the call to f (where f will return).
+//
+// The call to getcallerpc and getcallersp must be done in the
+// frame being asked about.
+//
+// The result of getcallersp is correct at the time of the return,
+// but it may be invalidated by any subsequent call to a function
+// that might relocate the stack in order to grow or shrink it.
+// A general rule is that the result of getcallersp should be used
+// immediately and can only be passed to nosplit functions.
+
+//go:noescape
+func getcallerpc() uintptr
+
+//go:noescape
+func getcallersp() uintptr // implemented as an intrinsic on all platforms
+
+// getclosureptr returns the pointer to the current closure.
+// getclosureptr can only be used in an assignment statement
+// at the entry of a function. Moreover, go:nosplit directive
+// must be specified at the declaration of caller function,
+// so that the function prolog does not clobber the closure register.
+// for example:
+//
+//	//go:nosplit
+//	func f(arg1, arg2, arg3 int) {
+//		dx := getclosureptr()
+//	}
+//
+// The compiler rewrites calls to this function into instructions that fetch the
+// pointer from a well-known register (DX on x86 architecture, etc.) directly.
+func getclosureptr() uintptr
+
+//go:noescape
+func asmcgocall(fn, arg unsafe.Pointer) int32
+
+func morestack()
+func morestack_noctxt()
+func rt0_go()
+
+// return0 is a stub used to return 0 from deferproc.
+// It is called at the very end of deferproc to signal
+// the calling Go function that it should not jump
+// to deferreturn.
+// in asm_*.s
+func return0()
+
+// in asm_*.s
+// not called directly; definitions here supply type information for traceback.
+// These must have the same signature (arg pointer map) as reflectcall.
+func call16(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+func call32(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+func call64(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+func call128(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+func call256(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+func call512(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+func call1024(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+func call2048(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+func call4096(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+func call8192(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+func call16384(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+func call32768(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+func call65536(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+func call131072(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+func call262144(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+func call524288(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+func call1048576(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+func call2097152(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+func call4194304(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+func call8388608(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+func call16777216(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+func call33554432(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+func call67108864(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+func call134217728(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+func call268435456(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+func call536870912(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+func call1073741824(typ, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs)
+
+func systemstack_switch()
+
+// alignUp rounds n up to a multiple of a. a must be a power of 2.
+func alignUp(n, a uintptr) uintptr {
+	return (n + a - 1) &^ (a - 1)
+}
+
+// alignDown rounds n down to a multiple of a. a must be a power of 2.
+func alignDown(n, a uintptr) uintptr {
+	return n &^ (a - 1)
+}
+
+// divRoundUp returns ceil(n / a).
+func divRoundUp(n, a uintptr) uintptr {
+	// a is generally a power of two. This will get inlined and
+	// the compiler will optimize the division.
+	return (n + a - 1) / a
+}
+
+// checkASM reports whether assembly runtime checks have passed.
+func checkASM() bool
+
+func memequal_varlen(a, b unsafe.Pointer) bool
+
+// bool2int returns 0 if x is false or 1 if x is true.
+func bool2int(x bool) int {
+	// Avoid branches. In the SSA compiler, this compiles to
+	// exactly what you would want it to.
+	return int(uint8(*(*uint8)(unsafe.Pointer(&x))))
+}
+
+// abort crashes the runtime in situations where even throw might not
+// work. In general it should do something a debugger will recognize
+// (e.g., an INT3 on x86). A crash in abort is recognized by the
+// signal handler, which will attempt to tear down the runtime
+// immediately.
+func abort()
+
+// Called from compiled code; declared for vet; do NOT call from Go.
+func gcWriteBarrier()
+func duffzero()
+func duffcopy()
+
+// Called from linker-generated .initarray; declared for go vet; do NOT call from Go.
+func addmoduledata()
+
+// Injected by the signal handler for panicking signals.
+// Initializes any registers that have fixed meaning at calls but
+// are scratch in bodies and calls sigpanic.
+// On many platforms it just jumps to sigpanic.
+func sigpanic0()
+
+// intArgRegs is used by the various register assignment
+// algorithm implementations in the runtime. These include:.
+// - Finalizers (mfinal.go)
+// - Windows callbacks (syscall_windows.go)
+//
+// Both are stripped-down versions of the algorithm since they
+// only have to deal with a subset of cases (finalizers only
+// take a pointer or interface argument, Go Windows callbacks
+// don't support floating point).
+//
+// It should be modified with care and are generally only
+// modified when testing this package.
+//
+// It should never be set higher than its internal/abi
+// constant counterparts, because the system relies on a
+// structure that is at least large enough to hold the
+// registers the system supports.
+//
+// Protected by finlock.
+var intArgRegs = abi.IntArgRegs
diff --git a/contrib/go/_std_1.19/src/runtime/stubs2.go b/contrib/go/_std_1.19/src/runtime/stubs2.go
new file mode 100644
index 0000000000..94a888dec6
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/stubs2.go
@@ -0,0 +1,41 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !aix && !darwin && !js && !openbsd && !plan9 && !solaris && !windows
+
+package runtime
+
+import "unsafe"
+
+// read calls the read system call.
+// It returns a non-negative number of bytes written or a negative errno value.
+func read(fd int32, p unsafe.Pointer, n int32) int32
+
+func closefd(fd int32) int32
+
+func exit(code int32)
+func usleep(usec uint32)
+
+//go:nosplit
+func usleep_no_g(usec uint32) {
+	usleep(usec)
+}
+
+// write calls the write system call.
+// It returns a non-negative number of bytes written or a negative errno value.
+//
+//go:noescape
+func write1(fd uintptr, p unsafe.Pointer, n int32) int32
+
+//go:noescape
+func open(name *byte, mode, perm int32) int32
+
+// return value is only set on linux to be used in osinit()
+func madvise(addr unsafe.Pointer, n uintptr, flags int32) int32
+
+// exitThread terminates the current thread, writing *wait = 0 when
+// the stack is safe to reclaim.
+//
+//go:noescape
+func exitThread(wait *uint32)
diff --git a/contrib/go/_std_1.18/src/runtime/stubs3.go b/contrib/go/_std_1.19/src/runtime/stubs3.go
index 891663b110..891663b110 100644
--- a/contrib/go/_std_1.18/src/runtime/stubs3.go
+++ b/contrib/go/_std_1.19/src/runtime/stubs3.go
diff --git a/contrib/go/_std_1.18/src/runtime/stubs_amd64.go b/contrib/go/_std_1.19/src/runtime/stubs_amd64.go
index 687a506cdd..687a506cdd 100644
--- a/contrib/go/_std_1.18/src/runtime/stubs_amd64.go
+++ b/contrib/go/_std_1.19/src/runtime/stubs_amd64.go
diff --git a/contrib/go/_std_1.19/src/runtime/stubs_linux.go b/contrib/go/_std_1.19/src/runtime/stubs_linux.go
new file mode 100644
index 0000000000..2367dc2bd0
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/stubs_linux.go
@@ -0,0 +1,20 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build linux
+
+package runtime
+
+import "unsafe"
+
+func sbrk0() uintptr
+
+// Called from write_err_android.go only, but defined in sys_linux_*.s;
+// declared here (instead of in write_err_android.go) for go vet on non-android builds.
+// The return value is the raw syscall result, which may encode an error number.
+//
+//go:noescape
+func access(name *byte, mode int32) int32
+func connect(fd int32, addr unsafe.Pointer, len int32) int32
+func socket(domain int32, typ int32, prot int32) int32
diff --git a/contrib/go/_std_1.18/src/runtime/stubs_nonlinux.go b/contrib/go/_std_1.19/src/runtime/stubs_nonlinux.go
index 1a06d7cc1d..1a06d7cc1d 100644
--- a/contrib/go/_std_1.18/src/runtime/stubs_nonlinux.go
+++ b/contrib/go/_std_1.19/src/runtime/stubs_nonlinux.go
diff --git a/contrib/go/_std_1.19/src/runtime/symtab.go b/contrib/go/_std_1.19/src/runtime/symtab.go
new file mode 100644
index 0000000000..ad34b68c7d
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/symtab.go
@@ -0,0 +1,1183 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"internal/goarch"
+	"runtime/internal/atomic"
+	"runtime/internal/sys"
+	"unsafe"
+)
+
+// Frames may be used to get function/file/line information for a
+// slice of PC values returned by Callers.
+type Frames struct {
+	// callers is a slice of PCs that have not yet been expanded to frames.
+	callers []uintptr
+
+	// frames is a slice of Frames that have yet to be returned.
+	frames     []Frame
+	frameStore [2]Frame
+}
+
+// Frame is the information returned by Frames for each call frame.
+type Frame struct {
+	// PC is the program counter for the location in this frame.
+	// For a frame that calls another frame, this will be the
+	// program counter of a call instruction. Because of inlining,
+	// multiple frames may have the same PC value, but different
+	// symbolic information.
+	PC uintptr
+
+	// Func is the Func value of this call frame. This may be nil
+	// for non-Go code or fully inlined functions.
+	Func *Func
+
+	// Function is the package path-qualified function name of
+	// this call frame. If non-empty, this string uniquely
+	// identifies a single function in the program.
+	// This may be the empty string if not known.
+	// If Func is not nil then Function == Func.Name().
+	Function string
+
+	// File and Line are the file name and line number of the
+	// location in this frame. For non-leaf frames, this will be
+	// the location of a call. These may be the empty string and
+	// zero, respectively, if not known.
+	File string
+	Line int
+
+	// Entry point program counter for the function; may be zero
+	// if not known. If Func is not nil then Entry ==
+	// Func.Entry().
+	Entry uintptr
+
+	// The runtime's internal view of the function. This field
+	// is set (funcInfo.valid() returns true) only for Go functions,
+	// not for C functions.
+	funcInfo funcInfo
+}
+
+// CallersFrames takes a slice of PC values returned by Callers and
+// prepares to return function/file/line information.
+// Do not change the slice until you are done with the Frames.
+func CallersFrames(callers []uintptr) *Frames {
+	f := &Frames{callers: callers}
+	f.frames = f.frameStore[:0]
+	return f
+}
+
+// Next returns a Frame representing the next call frame in the slice
+// of PC values. If it has already returned all call frames, Next
+// returns a zero Frame.
+//
+// The more result indicates whether the next call to Next will return
+// a valid Frame. It does not necessarily indicate whether this call
+// returned one.
+//
+// See the Frames example for idiomatic usage.
+func (ci *Frames) Next() (frame Frame, more bool) {
+	for len(ci.frames) < 2 {
+		// Find the next frame.
+		// We need to look for 2 frames so we know what
+		// to return for the "more" result.
+		if len(ci.callers) == 0 {
+			break
+		}
+		pc := ci.callers[0]
+		ci.callers = ci.callers[1:]
+		funcInfo := findfunc(pc)
+		if !funcInfo.valid() {
+			if cgoSymbolizer != nil {
+				// Pre-expand cgo frames. We could do this
+				// incrementally, too, but there's no way to
+				// avoid allocation in this case anyway.
+				ci.frames = append(ci.frames, expandCgoFrames(pc)...)
+			}
+			continue
+		}
+		f := funcInfo._Func()
+		entry := f.Entry()
+		if pc > entry {
+			// We store the pc of the start of the instruction following
+			// the instruction in question (the call or the inline mark).
+			// This is done for historical reasons, and to make FuncForPC
+			// work correctly for entries in the result of runtime.Callers.
+			pc--
+		}
+		name := funcname(funcInfo)
+		if inldata := funcdata(funcInfo, _FUNCDATA_InlTree); inldata != nil {
+			inltree := (*[1 << 20]inlinedCall)(inldata)
+			// Non-strict as cgoTraceback may have added bogus PCs
+			// with a valid funcInfo but invalid PCDATA.
+			ix := pcdatavalue1(funcInfo, _PCDATA_InlTreeIndex, pc, nil, false)
+			if ix >= 0 {
+				// Note: entry is not modified. It always refers to a real frame, not an inlined one.
+				f = nil
+				name = funcnameFromNameoff(funcInfo, inltree[ix].func_)
+				// File/line is already correct.
+				// TODO: remove file/line from InlinedCall?
+			}
+		}
+		ci.frames = append(ci.frames, Frame{
+			PC:       pc,
+			Func:     f,
+			Function: name,
+			Entry:    entry,
+			funcInfo: funcInfo,
+			// Note: File,Line set below
+		})
+	}
+
+	// Pop one frame from the frame list. Keep the rest.
+	// Avoid allocation in the common case, which is 1 or 2 frames.
+	switch len(ci.frames) {
+	case 0: // In the rare case when there are no frames at all, we return Frame{}.
+		return
+	case 1:
+		frame = ci.frames[0]
+		ci.frames = ci.frameStore[:0]
+	case 2:
+		frame = ci.frames[0]
+		ci.frameStore[0] = ci.frames[1]
+		ci.frames = ci.frameStore[:1]
+	default:
+		frame = ci.frames[0]
+		ci.frames = ci.frames[1:]
+	}
+	more = len(ci.frames) > 0
+	if frame.funcInfo.valid() {
+		// Compute file/line just before we need to return it,
+		// as it can be expensive. This avoids computing file/line
+		// for the Frame we find but don't return. See issue 32093.
+		file, line := funcline1(frame.funcInfo, frame.PC, false)
+		frame.File, frame.Line = file, int(line)
+	}
+	return
+}
+
+// runtime_expandFinalInlineFrame expands the final pc in stk to include all
+// "callers" if pc is inline.
+//
+//go:linkname runtime_expandFinalInlineFrame runtime/pprof.runtime_expandFinalInlineFrame
+func runtime_expandFinalInlineFrame(stk []uintptr) []uintptr {
+	if len(stk) == 0 {
+		return stk
+	}
+	pc := stk[len(stk)-1]
+	tracepc := pc - 1
+
+	f := findfunc(tracepc)
+	if !f.valid() {
+		// Not a Go function.
+		return stk
+	}
+
+	inldata := funcdata(f, _FUNCDATA_InlTree)
+	if inldata == nil {
+		// Nothing inline in f.
+		return stk
+	}
+
+	// Treat the previous func as normal. We haven't actually checked, but
+	// since this pc was included in the stack, we know it shouldn't be
+	// elided.
+	lastFuncID := funcID_normal
+
+	// Remove pc from stk; we'll re-add it below.
+	stk = stk[:len(stk)-1]
+
+	// See inline expansion in gentraceback.
+	var cache pcvalueCache
+	inltree := (*[1 << 20]inlinedCall)(inldata)
+	for {
+		// Non-strict as cgoTraceback may have added bogus PCs
+		// with a valid funcInfo but invalid PCDATA.
+		ix := pcdatavalue1(f, _PCDATA_InlTreeIndex, tracepc, &cache, false)
+		if ix < 0 {
+			break
+		}
+		if inltree[ix].funcID == funcID_wrapper && elideWrapperCalling(lastFuncID) {
+			// ignore wrappers
+		} else {
+			stk = append(stk, pc)
+		}
+		lastFuncID = inltree[ix].funcID
+		// Back up to an instruction in the "caller".
+		tracepc = f.entry() + uintptr(inltree[ix].parentPc)
+		pc = tracepc + 1
+	}
+
+	// N.B. we want to keep the last parentPC which is not inline.
+	stk = append(stk, pc)
+
+	return stk
+}
+
+// expandCgoFrames expands frame information for pc, known to be
+// a non-Go function, using the cgoSymbolizer hook. expandCgoFrames
+// returns nil if pc could not be expanded.
+func expandCgoFrames(pc uintptr) []Frame {
+	arg := cgoSymbolizerArg{pc: pc}
+	callCgoSymbolizer(&arg)
+
+	if arg.file == nil && arg.funcName == nil {
+		// No useful information from symbolizer.
+		return nil
+	}
+
+	var frames []Frame
+	for {
+		frames = append(frames, Frame{
+			PC:       pc,
+			Func:     nil,
+			Function: gostring(arg.funcName),
+			File:     gostring(arg.file),
+			Line:     int(arg.lineno),
+			Entry:    arg.entry,
+			// funcInfo is zero, which implies !funcInfo.valid().
+			// That ensures that we use the File/Line info given here.
+		})
+		if arg.more == 0 {
+			break
+		}
+		callCgoSymbolizer(&arg)
+	}
+
+	// No more frames for this PC. Tell the symbolizer we are done.
+	// We don't try to maintain a single cgoSymbolizerArg for the
+	// whole use of Frames, because there would be no good way to tell
+	// the symbolizer when we are done.
+	arg.pc = 0
+	callCgoSymbolizer(&arg)
+
+	return frames
+}
+
+// NOTE: Func does not expose the actual unexported fields, because we return *Func
+// values to users, and we want to keep them from being able to overwrite the data
+// with (say) *f = Func{}.
+// All code operating on a *Func must call raw() to get the *_func
+// or funcInfo() to get the funcInfo instead.
+
+// A Func represents a Go function in the running binary.
+type Func struct {
+	opaque struct{} // unexported field to disallow conversions
+}
+
+func (f *Func) raw() *_func {
+	return (*_func)(unsafe.Pointer(f))
+}
+
+func (f *Func) funcInfo() funcInfo {
+	return f.raw().funcInfo()
+}
+
+func (f *_func) funcInfo() funcInfo {
+	// Find the module containing fn. fn is located in the pclntable.
+	// The unsafe.Pointer to uintptr conversions and arithmetic
+	// are safe because we are working with module addresses.
+	ptr := uintptr(unsafe.Pointer(f))
+	var mod *moduledata
+	for datap := &firstmoduledata; datap != nil; datap = datap.next {
+		if len(datap.pclntable) == 0 {
+			continue
+		}
+		base := uintptr(unsafe.Pointer(&datap.pclntable[0]))
+		if base <= ptr && ptr < base+uintptr(len(datap.pclntable)) {
+			mod = datap
+			break
+		}
+	}
+	return funcInfo{f, mod}
+}
+
+// PCDATA and FUNCDATA table indexes.
+//
+// See funcdata.h and ../cmd/internal/objabi/funcdata.go.
+const (
+	_PCDATA_UnsafePoint   = 0
+	_PCDATA_StackMapIndex = 1
+	_PCDATA_InlTreeIndex  = 2
+	_PCDATA_ArgLiveIndex  = 3
+
+	_FUNCDATA_ArgsPointerMaps    = 0
+	_FUNCDATA_LocalsPointerMaps  = 1
+	_FUNCDATA_StackObjects       = 2
+	_FUNCDATA_InlTree            = 3
+	_FUNCDATA_OpenCodedDeferInfo = 4
+	_FUNCDATA_ArgInfo            = 5
+	_FUNCDATA_ArgLiveInfo        = 6
+	_FUNCDATA_WrapInfo           = 7
+
+	_ArgsSizeUnknown = -0x80000000
+)
+
+const (
+	// PCDATA_UnsafePoint values.
+	_PCDATA_UnsafePointSafe   = -1 // Safe for async preemption
+	_PCDATA_UnsafePointUnsafe = -2 // Unsafe for async preemption
+
+	// _PCDATA_Restart1(2) apply on a sequence of instructions, within
+	// which if an async preemption happens, we should back off the PC
+	// to the start of the sequence when resume.
+	// We need two so we can distinguish the start/end of the sequence
+	// in case that two sequences are next to each other.
+	_PCDATA_Restart1 = -3
+	_PCDATA_Restart2 = -4
+
+	// Like _PCDATA_RestartAtEntry, but back to function entry if async
+	// preempted.
+	_PCDATA_RestartAtEntry = -5
+)
+
+// A FuncID identifies particular functions that need to be treated
+// specially by the runtime.
+// Note that in some situations involving plugins, there may be multiple
+// copies of a particular special runtime function.
+// Note: this list must match the list in cmd/internal/objabi/funcid.go.
+type funcID uint8
+
+const (
+	funcID_normal funcID = iota // not a special function
+	funcID_abort
+	funcID_asmcgocall
+	funcID_asyncPreempt
+	funcID_cgocallback
+	funcID_debugCallV2
+	funcID_gcBgMarkWorker
+	funcID_goexit
+	funcID_gogo
+	funcID_gopanic
+	funcID_handleAsyncEvent
+	funcID_mcall
+	funcID_morestack
+	funcID_mstart
+	funcID_panicwrap
+	funcID_rt0_go
+	funcID_runfinq
+	funcID_runtime_main
+	funcID_sigpanic
+	funcID_systemstack
+	funcID_systemstack_switch
+	funcID_wrapper // any autogenerated code (hash/eq algorithms, method wrappers, etc.)
+)
+
+// A FuncFlag holds bits about a function.
+// This list must match the list in cmd/internal/objabi/funcid.go.
+type funcFlag uint8
+
+const (
+	// TOPFRAME indicates a function that appears at the top of its stack.
+	// The traceback routine stop at such a function and consider that a
+	// successful, complete traversal of the stack.
+	// Examples of TOPFRAME functions include goexit, which appears
+	// at the top of a user goroutine stack, and mstart, which appears
+	// at the top of a system goroutine stack.
+	funcFlag_TOPFRAME funcFlag = 1 << iota
+
+	// SPWRITE indicates a function that writes an arbitrary value to SP
+	// (any write other than adding or subtracting a constant amount).
+	// The traceback routines cannot encode such changes into the
+	// pcsp tables, so the function traceback cannot safely unwind past
+	// SPWRITE functions. Stopping at an SPWRITE function is considered
+	// to be an incomplete unwinding of the stack. In certain contexts
+	// (in particular garbage collector stack scans) that is a fatal error.
+	funcFlag_SPWRITE
+
+	// ASM indicates that a function was implemented in assembly.
+	funcFlag_ASM
+)
+
+// pcHeader holds data used by the pclntab lookups.
+type pcHeader struct {
+	magic          uint32  // 0xFFFFFFF0
+	pad1, pad2     uint8   // 0,0
+	minLC          uint8   // min instruction size
+	ptrSize        uint8   // size of a ptr in bytes
+	nfunc          int     // number of functions in the module
+	nfiles         uint    // number of entries in the file tab
+	textStart      uintptr // base for function entry PC offsets in this module, equal to moduledata.text
+	funcnameOffset uintptr // offset to the funcnametab variable from pcHeader
+	cuOffset       uintptr // offset to the cutab variable from pcHeader
+	filetabOffset  uintptr // offset to the filetab variable from pcHeader
+	pctabOffset    uintptr // offset to the pctab variable from pcHeader
+	pclnOffset     uintptr // offset to the pclntab variable from pcHeader
+}
+
+// moduledata records information about the layout of the executable
+// image. It is written by the linker. Any changes here must be
+// matched changes to the code in cmd/link/internal/ld/symtab.go:symtab.
+// moduledata is stored in statically allocated non-pointer memory;
+// none of the pointers here are visible to the garbage collector.
+type moduledata struct {
+	pcHeader     *pcHeader
+	funcnametab  []byte
+	cutab        []uint32
+	filetab      []byte
+	pctab        []byte
+	pclntable    []byte
+	ftab         []functab
+	findfunctab  uintptr
+	minpc, maxpc uintptr
+
+	text, etext           uintptr
+	noptrdata, enoptrdata uintptr
+	data, edata           uintptr
+	bss, ebss             uintptr
+	noptrbss, enoptrbss   uintptr
+	end, gcdata, gcbss    uintptr
+	types, etypes         uintptr
+	rodata                uintptr
+	gofunc                uintptr // go.func.*
+
+	textsectmap []textsect
+	typelinks   []int32 // offsets from types
+	itablinks   []*itab
+
+	ptab []ptabEntry
+
+	pluginpath string
+	pkghashes  []modulehash
+
+	modulename   string
+	modulehashes []modulehash
+
+	hasmain uint8 // 1 if module contains the main function, 0 otherwise
+
+	gcdatamask, gcbssmask bitvector
+
+	typemap map[typeOff]*_type // offset to *_rtype in previous module
+
+	bad bool // module failed to load and should be ignored
+
+	next *moduledata
+}
+
+// A modulehash is used to compare the ABI of a new module or a
+// package in a new module with the loaded program.
+//
+// For each shared library a module links against, the linker creates an entry in the
+// moduledata.modulehashes slice containing the name of the module, the abi hash seen
+// at link time and a pointer to the runtime abi hash. These are checked in
+// moduledataverify1 below.
+//
+// For each loaded plugin, the pkghashes slice has a modulehash of the
+// newly loaded package that can be used to check the plugin's version of
+// a package against any previously loaded version of the package.
+// This is done in plugin.lastmoduleinit.
+type modulehash struct {
+	modulename   string
+	linktimehash string
+	runtimehash  *string
+}
+
+// pinnedTypemaps are the map[typeOff]*_type from the moduledata objects.
+//
+// These typemap objects are allocated at run time on the heap, but the
+// only direct reference to them is in the moduledata, created by the
+// linker and marked SNOPTRDATA so it is ignored by the GC.
+//
+// To make sure the map isn't collected, we keep a second reference here.
+var pinnedTypemaps []map[typeOff]*_type
+
+var firstmoduledata moduledata  // linker symbol
+var lastmoduledatap *moduledata // linker symbol
+var modulesSlice *[]*moduledata // see activeModules
+
+// activeModules returns a slice of active modules.
+//
+// A module is active once its gcdatamask and gcbssmask have been
+// assembled and it is usable by the GC.
+//
+// This is nosplit/nowritebarrier because it is called by the
+// cgo pointer checking code.
+//
+//go:nosplit
+//go:nowritebarrier
+func activeModules() []*moduledata {
+	p := (*[]*moduledata)(atomic.Loadp(unsafe.Pointer(&modulesSlice)))
+	if p == nil {
+		return nil
+	}
+	return *p
+}
+
+// modulesinit creates the active modules slice out of all loaded modules.
+//
+// When a module is first loaded by the dynamic linker, an .init_array
+// function (written by cmd/link) is invoked to call addmoduledata,
+// appending to the module to the linked list that starts with
+// firstmoduledata.
+//
+// There are two times this can happen in the lifecycle of a Go
+// program. First, if compiled with -linkshared, a number of modules
+// built with -buildmode=shared can be loaded at program initialization.
+// Second, a Go program can load a module while running that was built
+// with -buildmode=plugin.
+//
+// After loading, this function is called which initializes the
+// moduledata so it is usable by the GC and creates a new activeModules
+// list.
+//
+// Only one goroutine may call modulesinit at a time.
+func modulesinit() {
+	modules := new([]*moduledata)
+	for md := &firstmoduledata; md != nil; md = md.next {
+		if md.bad {
+			continue
+		}
+		*modules = append(*modules, md)
+		if md.gcdatamask == (bitvector{}) {
+			scanDataSize := md.edata - md.data
+			md.gcdatamask = progToPointerMask((*byte)(unsafe.Pointer(md.gcdata)), scanDataSize)
+			scanBSSSize := md.ebss - md.bss
+			md.gcbssmask = progToPointerMask((*byte)(unsafe.Pointer(md.gcbss)), scanBSSSize)
+			gcController.addGlobals(int64(scanDataSize + scanBSSSize))
+		}
+	}
+
+	// Modules appear in the moduledata linked list in the order they are
+	// loaded by the dynamic loader, with one exception: the
+	// firstmoduledata itself the module that contains the runtime. This
+	// is not always the first module (when using -buildmode=shared, it
+	// is typically libstd.so, the second module). The order matters for
+	// typelinksinit, so we swap the first module with whatever module
+	// contains the main function.
+	//
+	// See Issue #18729.
+	for i, md := range *modules {
+		if md.hasmain != 0 {
+			(*modules)[0] = md
+			(*modules)[i] = &firstmoduledata
+			break
+		}
+	}
+
+	atomicstorep(unsafe.Pointer(&modulesSlice), unsafe.Pointer(modules))
+}
+
+type functab struct {
+	entryoff uint32 // relative to runtime.text
+	funcoff  uint32
+}
+
+// Mapping information for secondary text sections
+
+type textsect struct {
+	vaddr    uintptr // prelinked section vaddr
+	end      uintptr // vaddr + section length
+	baseaddr uintptr // relocated section address
+}
+
+const minfunc = 16                 // minimum function size
+const pcbucketsize = 256 * minfunc // size of bucket in the pc->func lookup table
+
+// findfunctab is an array of these structures.
+// Each bucket represents 4096 bytes of the text segment.
+// Each subbucket represents 256 bytes of the text segment.
+// To find a function given a pc, locate the bucket and subbucket for
+// that pc. Add together the idx and subbucket value to obtain a
+// function index. Then scan the functab array starting at that
+// index to find the target function.
+// This table uses 20 bytes for every 4096 bytes of code, or ~0.5% overhead.
+type findfuncbucket struct {
+	idx        uint32
+	subbuckets [16]byte
+}
+
+func moduledataverify() {
+	for datap := &firstmoduledata; datap != nil; datap = datap.next {
+		moduledataverify1(datap)
+	}
+}
+
+const debugPcln = false
+
+func moduledataverify1(datap *moduledata) {
+	// Check that the pclntab's format is valid.
+	hdr := datap.pcHeader
+	if hdr.magic != 0xfffffff0 || hdr.pad1 != 0 || hdr.pad2 != 0 ||
+		hdr.minLC != sys.PCQuantum || hdr.ptrSize != goarch.PtrSize || hdr.textStart != datap.text {
+		println("runtime: pcHeader: magic=", hex(hdr.magic), "pad1=", hdr.pad1, "pad2=", hdr.pad2,
+			"minLC=", hdr.minLC, "ptrSize=", hdr.ptrSize, "pcHeader.textStart=", hex(hdr.textStart),
+			"text=", hex(datap.text), "pluginpath=", datap.pluginpath)
+		throw("invalid function symbol table")
+	}
+
+	// ftab is lookup table for function by program counter.
+	nftab := len(datap.ftab) - 1
+	for i := 0; i < nftab; i++ {
+		// NOTE: ftab[nftab].entry is legal; it is the address beyond the final function.
+		if datap.ftab[i].entryoff > datap.ftab[i+1].entryoff {
+			f1 := funcInfo{(*_func)(unsafe.Pointer(&datap.pclntable[datap.ftab[i].funcoff])), datap}
+			f2 := funcInfo{(*_func)(unsafe.Pointer(&datap.pclntable[datap.ftab[i+1].funcoff])), datap}
+			f2name := "end"
+			if i+1 < nftab {
+				f2name = funcname(f2)
+			}
+			println("function symbol table not sorted by PC offset:", hex(datap.ftab[i].entryoff), funcname(f1), ">", hex(datap.ftab[i+1].entryoff), f2name, ", plugin:", datap.pluginpath)
+			for j := 0; j <= i; j++ {
+				println("\t", hex(datap.ftab[j].entryoff), funcname(funcInfo{(*_func)(unsafe.Pointer(&datap.pclntable[datap.ftab[j].funcoff])), datap}))
+			}
+			if GOOS == "aix" && isarchive {
+				println("-Wl,-bnoobjreorder is mandatory on aix/ppc64 with c-archive")
+			}
+			throw("invalid runtime symbol table")
+		}
+	}
+
+	min := datap.textAddr(datap.ftab[0].entryoff)
+	max := datap.textAddr(datap.ftab[nftab].entryoff)
+	if datap.minpc != min || datap.maxpc != max {
+		println("minpc=", hex(datap.minpc), "min=", hex(min), "maxpc=", hex(datap.maxpc), "max=", hex(max))
+		throw("minpc or maxpc invalid")
+	}
+
+	for _, modulehash := range datap.modulehashes {
+		if modulehash.linktimehash != *modulehash.runtimehash {
+			println("abi mismatch detected between", datap.modulename, "and", modulehash.modulename)
+			throw("abi mismatch")
+		}
+	}
+}
+
+// textAddr returns md.text + off, with special handling for multiple text sections.
+// off is a (virtual) offset computed at internal linking time,
+// before the external linker adjusts the sections' base addresses.
+//
+// The text, or instruction stream is generated as one large buffer.
+// The off (offset) for a function is its offset within this buffer.
+// If the total text size gets too large, there can be issues on platforms like ppc64
+// if the target of calls are too far for the call instruction.
+// To resolve the large text issue, the text is split into multiple text sections
+// to allow the linker to generate long calls when necessary.
+// When this happens, the vaddr for each text section is set to its offset within the text.
+// Each function's offset is compared against the section vaddrs and ends to determine the containing section.
+// Then the section relative offset is added to the section's
+// relocated baseaddr to compute the function address.
+//
+// It is nosplit because it is part of the findfunc implementation.
+//
+//go:nosplit
+func (md *moduledata) textAddr(off32 uint32) uintptr {
+	off := uintptr(off32)
+	res := md.text + off
+	if len(md.textsectmap) > 1 {
+		for i, sect := range md.textsectmap {
+			// For the last section, include the end address (etext), as it is included in the functab.
+			if off >= sect.vaddr && off < sect.end || (i == len(md.textsectmap)-1 && off == sect.end) {
+				res = sect.baseaddr + off - sect.vaddr
+				break
+			}
+		}
+		if res > md.etext && GOARCH != "wasm" { // on wasm, functions do not live in the same address space as the linear memory
+			println("runtime: textAddr", hex(res), "out of range", hex(md.text), "-", hex(md.etext))
+			throw("runtime: text offset out of range")
+		}
+	}
+	return res
+}
+
+// textOff is the opposite of textAddr. It converts a PC to a (virtual) offset
+// to md.text, and returns if the PC is in any Go text section.
+//
+// It is nosplit because it is part of the findfunc implementation.
+//
+//go:nosplit
+func (md *moduledata) textOff(pc uintptr) (uint32, bool) {
+	res := uint32(pc - md.text)
+	if len(md.textsectmap) > 1 {
+		for i, sect := range md.textsectmap {
+			if sect.baseaddr > pc {
+				// pc is not in any section.
+				return 0, false
+			}
+			end := sect.baseaddr + (sect.end - sect.vaddr)
+			// For the last section, include the end address (etext), as it is included in the functab.
+			if i == len(md.textsectmap) {
+				end++
+			}
+			if pc < end {
+				res = uint32(pc - sect.baseaddr + sect.vaddr)
+				break
+			}
+		}
+	}
+	return res, true
+}
+
+// FuncForPC returns a *Func describing the function that contains the
+// given program counter address, or else nil.
+//
+// If pc represents multiple functions because of inlining, it returns
+// the *Func describing the innermost function, but with an entry of
+// the outermost function.
+func FuncForPC(pc uintptr) *Func {
+	f := findfunc(pc)
+	if !f.valid() {
+		return nil
+	}
+	if inldata := funcdata(f, _FUNCDATA_InlTree); inldata != nil {
+		// Note: strict=false so bad PCs (those between functions) don't crash the runtime.
+		// We just report the preceding function in that situation. See issue 29735.
+		// TODO: Perhaps we should report no function at all in that case.
+		// The runtime currently doesn't have function end info, alas.
+		if ix := pcdatavalue1(f, _PCDATA_InlTreeIndex, pc, nil, false); ix >= 0 {
+			inltree := (*[1 << 20]inlinedCall)(inldata)
+			name := funcnameFromNameoff(f, inltree[ix].func_)
+			file, line := funcline(f, pc)
+			fi := &funcinl{
+				ones:  ^uint32(0),
+				entry: f.entry(), // entry of the real (the outermost) function.
+				name:  name,
+				file:  file,
+				line:  int(line),
+			}
+			return (*Func)(unsafe.Pointer(fi))
+		}
+	}
+	return f._Func()
+}
+
+// Name returns the name of the function.
+func (f *Func) Name() string {
+	if f == nil {
+		return ""
+	}
+	fn := f.raw()
+	if fn.isInlined() { // inlined version
+		fi := (*funcinl)(unsafe.Pointer(fn))
+		return fi.name
+	}
+	return funcname(f.funcInfo())
+}
+
+// Entry returns the entry address of the function.
+func (f *Func) Entry() uintptr {
+	fn := f.raw()
+	if fn.isInlined() { // inlined version
+		fi := (*funcinl)(unsafe.Pointer(fn))
+		return fi.entry
+	}
+	return fn.funcInfo().entry()
+}
+
+// FileLine returns the file name and line number of the
+// source code corresponding to the program counter pc.
+// The result will not be accurate if pc is not a program
+// counter within f.
+func (f *Func) FileLine(pc uintptr) (file string, line int) {
+	fn := f.raw()
+	if fn.isInlined() { // inlined version
+		fi := (*funcinl)(unsafe.Pointer(fn))
+		return fi.file, fi.line
+	}
+	// Pass strict=false here, because anyone can call this function,
+	// and they might just be wrong about targetpc belonging to f.
+	file, line32 := funcline1(f.funcInfo(), pc, false)
+	return file, int(line32)
+}
+
+// findmoduledatap looks up the moduledata for a PC.
+//
+// It is nosplit because it's part of the isgoexception
+// implementation.
+//
+//go:nosplit
+func findmoduledatap(pc uintptr) *moduledata {
+	for datap := &firstmoduledata; datap != nil; datap = datap.next {
+		if datap.minpc <= pc && pc < datap.maxpc {
+			return datap
+		}
+	}
+	return nil
+}
+
+type funcInfo struct {
+	*_func
+	datap *moduledata
+}
+
+func (f funcInfo) valid() bool {
+	return f._func != nil
+}
+
+func (f funcInfo) _Func() *Func {
+	return (*Func)(unsafe.Pointer(f._func))
+}
+
+// isInlined reports whether f should be re-interpreted as a *funcinl.
+func (f *_func) isInlined() bool {
+	return f.entryoff == ^uint32(0) // see comment for funcinl.ones
+}
+
+// entry returns the entry PC for f.
+func (f funcInfo) entry() uintptr {
+	return f.datap.textAddr(f.entryoff)
+}
+
+// findfunc looks up function metadata for a PC.
+//
+// It is nosplit because it's part of the isgoexception
+// implementation.
+//
+//go:nosplit
+func findfunc(pc uintptr) funcInfo {
+	datap := findmoduledatap(pc)
+	if datap == nil {
+		return funcInfo{}
+	}
+	const nsub = uintptr(len(findfuncbucket{}.subbuckets))
+
+	pcOff, ok := datap.textOff(pc)
+	if !ok {
+		return funcInfo{}
+	}
+
+	x := uintptr(pcOff) + datap.text - datap.minpc // TODO: are datap.text and datap.minpc always equal?
+	b := x / pcbucketsize
+	i := x % pcbucketsize / (pcbucketsize / nsub)
+
+	ffb := (*findfuncbucket)(add(unsafe.Pointer(datap.findfunctab), b*unsafe.Sizeof(findfuncbucket{})))
+	idx := ffb.idx + uint32(ffb.subbuckets[i])
+
+	// Find the ftab entry.
+	for datap.ftab[idx+1].entryoff <= pcOff {
+		idx++
+	}
+
+	funcoff := datap.ftab[idx].funcoff
+	return funcInfo{(*_func)(unsafe.Pointer(&datap.pclntable[funcoff])), datap}
+}
+
+type pcvalueCache struct {
+	entries [2][8]pcvalueCacheEnt
+}
+
+type pcvalueCacheEnt struct {
+	// targetpc and off together are the key of this cache entry.
+	targetpc uintptr
+	off      uint32
+	// val is the value of this cached pcvalue entry.
+	val int32
+}
+
+// pcvalueCacheKey returns the outermost index in a pcvalueCache to use for targetpc.
+// It must be very cheap to calculate.
+// For now, align to goarch.PtrSize and reduce mod the number of entries.
+// In practice, this appears to be fairly randomly and evenly distributed.
+func pcvalueCacheKey(targetpc uintptr) uintptr {
+	return (targetpc / goarch.PtrSize) % uintptr(len(pcvalueCache{}.entries))
+}
+
+// Returns the PCData value, and the PC where this value starts.
+// TODO: the start PC is returned only when cache is nil.
+func pcvalue(f funcInfo, off uint32, targetpc uintptr, cache *pcvalueCache, strict bool) (int32, uintptr) {
+	if off == 0 {
+		return -1, 0
+	}
+
+	// Check the cache. This speeds up walks of deep stacks, which
+	// tend to have the same recursive functions over and over.
+	//
+	// This cache is small enough that full associativity is
+	// cheaper than doing the hashing for a less associative
+	// cache.
+	if cache != nil {
+		x := pcvalueCacheKey(targetpc)
+		for i := range cache.entries[x] {
+			// We check off first because we're more
+			// likely to have multiple entries with
+			// different offsets for the same targetpc
+			// than the other way around, so we'll usually
+			// fail in the first clause.
+			ent := &cache.entries[x][i]
+			if ent.off == off && ent.targetpc == targetpc {
+				return ent.val, 0
+			}
+		}
+	}
+
+	if !f.valid() {
+		if strict && panicking == 0 {
+			println("runtime: no module data for", hex(f.entry()))
+			throw("no module data")
+		}
+		return -1, 0
+	}
+	datap := f.datap
+	p := datap.pctab[off:]
+	pc := f.entry()
+	prevpc := pc
+	val := int32(-1)
+	for {
+		var ok bool
+		p, ok = step(p, &pc, &val, pc == f.entry())
+		if !ok {
+			break
+		}
+		if targetpc < pc {
+			// Replace a random entry in the cache. Random
+			// replacement prevents a performance cliff if
+			// a recursive stack's cycle is slightly
+			// larger than the cache.
+			// Put the new element at the beginning,
+			// since it is the most likely to be newly used.
+			if cache != nil {
+				x := pcvalueCacheKey(targetpc)
+				e := &cache.entries[x]
+				ci := fastrandn(uint32(len(cache.entries[x])))
+				e[ci] = e[0]
+				e[0] = pcvalueCacheEnt{
+					targetpc: targetpc,
+					off:      off,
+					val:      val,
+				}
+			}
+
+			return val, prevpc
+		}
+		prevpc = pc
+	}
+
+	// If there was a table, it should have covered all program counters.
+	// If not, something is wrong.
+	if panicking != 0 || !strict {
+		return -1, 0
+	}
+
+	print("runtime: invalid pc-encoded table f=", funcname(f), " pc=", hex(pc), " targetpc=", hex(targetpc), " tab=", p, "\n")
+
+	p = datap.pctab[off:]
+	pc = f.entry()
+	val = -1
+	for {
+		var ok bool
+		p, ok = step(p, &pc, &val, pc == f.entry())
+		if !ok {
+			break
+		}
+		print("\tvalue=", val, " until pc=", hex(pc), "\n")
+	}
+
+	throw("invalid runtime symbol table")
+	return -1, 0
+}
+
+func cfuncname(f funcInfo) *byte {
+	if !f.valid() || f.nameoff == 0 {
+		return nil
+	}
+	return &f.datap.funcnametab[f.nameoff]
+}
+
+func funcname(f funcInfo) string {
+	return gostringnocopy(cfuncname(f))
+}
+
+func funcpkgpath(f funcInfo) string {
+	name := funcname(f)
+	i := len(name) - 1
+	for ; i > 0; i-- {
+		if name[i] == '/' {
+			break
+		}
+	}
+	for ; i < len(name); i++ {
+		if name[i] == '.' {
+			break
+		}
+	}
+	return name[:i]
+}
+
+func cfuncnameFromNameoff(f funcInfo, nameoff int32) *byte {
+	if !f.valid() {
+		return nil
+	}
+	return &f.datap.funcnametab[nameoff]
+}
+
+func funcnameFromNameoff(f funcInfo, nameoff int32) string {
+	return gostringnocopy(cfuncnameFromNameoff(f, nameoff))
+}
+
+func funcfile(f funcInfo, fileno int32) string {
+	datap := f.datap
+	if !f.valid() {
+		return "?"
+	}
+	// Make sure the cu index and file offset are valid
+	if fileoff := datap.cutab[f.cuOffset+uint32(fileno)]; fileoff != ^uint32(0) {
+		return gostringnocopy(&datap.filetab[fileoff])
+	}
+	// pcln section is corrupt.
+	return "?"
+}
+
+func funcline1(f funcInfo, targetpc uintptr, strict bool) (file string, line int32) {
+	datap := f.datap
+	if !f.valid() {
+		return "?", 0
+	}
+	fileno, _ := pcvalue(f, f.pcfile, targetpc, nil, strict)
+	line, _ = pcvalue(f, f.pcln, targetpc, nil, strict)
+	if fileno == -1 || line == -1 || int(fileno) >= len(datap.filetab) {
+		// print("looking for ", hex(targetpc), " in ", funcname(f), " got file=", fileno, " line=", lineno, "\n")
+		return "?", 0
+	}
+	file = funcfile(f, fileno)
+	return
+}
+
+func funcline(f funcInfo, targetpc uintptr) (file string, line int32) {
+	return funcline1(f, targetpc, true)
+}
+
+func funcspdelta(f funcInfo, targetpc uintptr, cache *pcvalueCache) int32 {
+	x, _ := pcvalue(f, f.pcsp, targetpc, cache, true)
+	if debugPcln && x&(goarch.PtrSize-1) != 0 {
+		print("invalid spdelta ", funcname(f), " ", hex(f.entry()), " ", hex(targetpc), " ", hex(f.pcsp), " ", x, "\n")
+		throw("bad spdelta")
+	}
+	return x
+}
+
+// funcMaxSPDelta returns the maximum spdelta at any point in f.
+func funcMaxSPDelta(f funcInfo) int32 {
+	datap := f.datap
+	p := datap.pctab[f.pcsp:]
+	pc := f.entry()
+	val := int32(-1)
+	max := int32(0)
+	for {
+		var ok bool
+		p, ok = step(p, &pc, &val, pc == f.entry())
+		if !ok {
+			return max
+		}
+		if val > max {
+			max = val
+		}
+	}
+}
+
+func pcdatastart(f funcInfo, table uint32) uint32 {
+	return *(*uint32)(add(unsafe.Pointer(&f.nfuncdata), unsafe.Sizeof(f.nfuncdata)+uintptr(table)*4))
+}
+
+func pcdatavalue(f funcInfo, table uint32, targetpc uintptr, cache *pcvalueCache) int32 {
+	if table >= f.npcdata {
+		return -1
+	}
+	r, _ := pcvalue(f, pcdatastart(f, table), targetpc, cache, true)
+	return r
+}
+
+func pcdatavalue1(f funcInfo, table uint32, targetpc uintptr, cache *pcvalueCache, strict bool) int32 {
+	if table >= f.npcdata {
+		return -1
+	}
+	r, _ := pcvalue(f, pcdatastart(f, table), targetpc, cache, strict)
+	return r
+}
+
+// Like pcdatavalue, but also return the start PC of this PCData value.
+// It doesn't take a cache.
+func pcdatavalue2(f funcInfo, table uint32, targetpc uintptr) (int32, uintptr) {
+	if table >= f.npcdata {
+		return -1, 0
+	}
+	return pcvalue(f, pcdatastart(f, table), targetpc, nil, true)
+}
+
+// funcdata returns a pointer to the ith funcdata for f.
+// funcdata should be kept in sync with cmd/link:writeFuncs.
+func funcdata(f funcInfo, i uint8) unsafe.Pointer {
+	if i < 0 || i >= f.nfuncdata {
+		return nil
+	}
+	base := f.datap.gofunc // load gofunc address early so that we calculate during cache misses
+	p := uintptr(unsafe.Pointer(&f.nfuncdata)) + unsafe.Sizeof(f.nfuncdata) + uintptr(f.npcdata)*4 + uintptr(i)*4
+	off := *(*uint32)(unsafe.Pointer(p))
+	// Return off == ^uint32(0) ? 0 : f.datap.gofunc + uintptr(off), but without branches.
+	// The compiler calculates mask on most architectures using conditional assignment.
+	var mask uintptr
+	if off == ^uint32(0) {
+		mask = 1
+	}
+	mask--
+	raw := base + uintptr(off)
+	return unsafe.Pointer(raw & mask)
+}
+
+// step advances to the next pc, value pair in the encoded table.
+func step(p []byte, pc *uintptr, val *int32, first bool) (newp []byte, ok bool) {
+	// For both uvdelta and pcdelta, the common case (~70%)
+	// is that they are a single byte. If so, avoid calling readvarint.
+	uvdelta := uint32(p[0])
+	if uvdelta == 0 && !first {
+		return nil, false
+	}
+	n := uint32(1)
+	if uvdelta&0x80 != 0 {
+		n, uvdelta = readvarint(p)
+	}
+	*val += int32(-(uvdelta & 1) ^ (uvdelta >> 1))
+	p = p[n:]
+
+	pcdelta := uint32(p[0])
+	n = 1
+	if pcdelta&0x80 != 0 {
+		n, pcdelta = readvarint(p)
+	}
+	p = p[n:]
+	*pc += uintptr(pcdelta * sys.PCQuantum)
+	return p, true
+}
+
+// readvarint reads a varint from p.
+func readvarint(p []byte) (read uint32, val uint32) {
+	var v, shift, n uint32
+	for {
+		b := p[n]
+		n++
+		v |= uint32(b&0x7F) << (shift & 31)
+		if b&0x80 == 0 {
+			break
+		}
+		shift += 7
+	}
+	return n, v
+}
+
+type stackmap struct {
+	n        int32   // number of bitmaps
+	nbit     int32   // number of bits in each bitmap
+	bytedata [1]byte // bitmaps, each starting on a byte boundary
+}
+
+//go:nowritebarrier
+func stackmapdata(stkmap *stackmap, n int32) bitvector {
+	// Check this invariant only when stackDebug is on at all.
+	// The invariant is already checked by many of stackmapdata's callers,
+	// and disabling it by default allows stackmapdata to be inlined.
+	if stackDebug > 0 && (n < 0 || n >= stkmap.n) {
+		throw("stackmapdata: index out of range")
+	}
+	return bitvector{stkmap.nbit, addb(&stkmap.bytedata[0], uintptr(n*((stkmap.nbit+7)>>3)))}
+}
+
+// inlinedCall is the encoding of entries in the FUNCDATA_InlTree table.
+type inlinedCall struct {
+	parent   int16  // index of parent in the inltree, or < 0
+	funcID   funcID // type of the called function
+	_        byte
+	file     int32 // perCU file index for inlined call. See cmd/link:pcln.go
+	line     int32 // line number of the call site
+	func_    int32 // offset into pclntab for name of called function
+	parentPc int32 // position of an instruction whose source position is the call site (offset from entry)
+}
diff --git a/contrib/go/_std_1.19/src/runtime/sys_darwin.go b/contrib/go/_std_1.19/src/runtime/sys_darwin.go
new file mode 100644
index 0000000000..1547fdceb0
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/sys_darwin.go
@@ -0,0 +1,537 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"internal/abi"
+	"unsafe"
+)
+
+// The X versions of syscall expect the libc call to return a 64-bit result.
+// Otherwise (the non-X version) expects a 32-bit result.
+// This distinction is required because an error is indicated by returning -1,
+// and we need to know whether to check 32 or 64 bits of the result.
+// (Some libc functions that return 32 bits put junk in the upper 32 bits of AX.)
+
+//go:linkname syscall_syscall syscall.syscall
+//go:nosplit
+func syscall_syscall(fn, a1, a2, a3 uintptr) (r1, r2, err uintptr) {
+	args := struct{ fn, a1, a2, a3, r1, r2, err uintptr }{fn, a1, a2, a3, r1, r2, err}
+	entersyscall()
+	libcCall(unsafe.Pointer(abi.FuncPCABI0(syscall)), unsafe.Pointer(&args))
+	exitsyscall()
+	return args.r1, args.r2, args.err
+}
+func syscall()
+
+//go:linkname syscall_syscallX syscall.syscallX
+//go:nosplit
+func syscall_syscallX(fn, a1, a2, a3 uintptr) (r1, r2, err uintptr) {
+	args := struct{ fn, a1, a2, a3, r1, r2, err uintptr }{fn, a1, a2, a3, r1, r2, err}
+	entersyscall()
+	libcCall(unsafe.Pointer(abi.FuncPCABI0(syscallX)), unsafe.Pointer(&args))
+	exitsyscall()
+	return args.r1, args.r2, args.err
+}
+func syscallX()
+
+//go:linkname syscall_syscall6 syscall.syscall6
+//go:nosplit
+func syscall_syscall6(fn, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr) {
+	args := struct{ fn, a1, a2, a3, a4, a5, a6, r1, r2, err uintptr }{fn, a1, a2, a3, a4, a5, a6, r1, r2, err}
+	entersyscall()
+	libcCall(unsafe.Pointer(abi.FuncPCABI0(syscall6)), unsafe.Pointer(&args))
+	exitsyscall()
+	return args.r1, args.r2, args.err
+}
+func syscall6()
+
+//go:linkname syscall_syscall6X syscall.syscall6X
+//go:nosplit
+func syscall_syscall6X(fn, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr) {
+	args := struct{ fn, a1, a2, a3, a4, a5, a6, r1, r2, err uintptr }{fn, a1, a2, a3, a4, a5, a6, r1, r2, err}
+	entersyscall()
+	libcCall(unsafe.Pointer(abi.FuncPCABI0(syscall6X)), unsafe.Pointer(&args))
+	exitsyscall()
+	return args.r1, args.r2, args.err
+}
+func syscall6X()
+
+//go:linkname syscall_syscallPtr syscall.syscallPtr
+//go:nosplit
+func syscall_syscallPtr(fn, a1, a2, a3 uintptr) (r1, r2, err uintptr) {
+	args := struct{ fn, a1, a2, a3, r1, r2, err uintptr }{fn, a1, a2, a3, r1, r2, err}
+	entersyscall()
+	libcCall(unsafe.Pointer(abi.FuncPCABI0(syscallPtr)), unsafe.Pointer(&args))
+	exitsyscall()
+	return args.r1, args.r2, args.err
+}
+func syscallPtr()
+
+//go:linkname syscall_rawSyscall syscall.rawSyscall
+//go:nosplit
+func syscall_rawSyscall(fn, a1, a2, a3 uintptr) (r1, r2, err uintptr) {
+	args := struct{ fn, a1, a2, a3, r1, r2, err uintptr }{fn, a1, a2, a3, r1, r2, err}
+	libcCall(unsafe.Pointer(abi.FuncPCABI0(syscall)), unsafe.Pointer(&args))
+	return args.r1, args.r2, args.err
+}
+
+//go:linkname syscall_rawSyscall6 syscall.rawSyscall6
+//go:nosplit
+func syscall_rawSyscall6(fn, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr) {
+	args := struct{ fn, a1, a2, a3, a4, a5, a6, r1, r2, err uintptr }{fn, a1, a2, a3, a4, a5, a6, r1, r2, err}
+	libcCall(unsafe.Pointer(abi.FuncPCABI0(syscall6)), unsafe.Pointer(&args))
+	return args.r1, args.r2, args.err
+}
+
+// syscallNoErr is used in crypto/x509 to call into Security.framework and CF.
+
+//go:linkname crypto_x509_syscall crypto/x509/internal/macos.syscall
+//go:nosplit
+func crypto_x509_syscall(fn, a1, a2, a3, a4, a5 uintptr, f1 float64) (r1 uintptr) {
+	args := struct {
+		fn, a1, a2, a3, a4, a5 uintptr
+		f1                     float64
+		r1                     uintptr
+	}{fn, a1, a2, a3, a4, a5, f1, r1}
+	entersyscall()
+	libcCall(unsafe.Pointer(abi.FuncPCABI0(syscall_x509)), unsafe.Pointer(&args))
+	exitsyscall()
+	return args.r1
+}
+func syscall_x509()
+
+// The *_trampoline functions convert from the Go calling convention to the C calling convention
+// and then call the underlying libc function.  They are defined in sys_darwin_$ARCH.s.
+
+//go:nosplit
+//go:cgo_unsafe_args
+func pthread_attr_init(attr *pthreadattr) int32 {
+	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(pthread_attr_init_trampoline)), unsafe.Pointer(&attr))
+	KeepAlive(attr)
+	return ret
+}
+func pthread_attr_init_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func pthread_attr_getstacksize(attr *pthreadattr, size *uintptr) int32 {
+	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(pthread_attr_getstacksize_trampoline)), unsafe.Pointer(&attr))
+	KeepAlive(attr)
+	KeepAlive(size)
+	return ret
+}
+func pthread_attr_getstacksize_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func pthread_attr_setdetachstate(attr *pthreadattr, state int) int32 {
+	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(pthread_attr_setdetachstate_trampoline)), unsafe.Pointer(&attr))
+	KeepAlive(attr)
+	return ret
+}
+func pthread_attr_setdetachstate_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func pthread_create(attr *pthreadattr, start uintptr, arg unsafe.Pointer) int32 {
+	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(pthread_create_trampoline)), unsafe.Pointer(&attr))
+	KeepAlive(attr)
+	KeepAlive(arg) // Just for consistency. Arg of course needs to be kept alive for the start function.
+	return ret
+}
+func pthread_create_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func raise(sig uint32) {
+	libcCall(unsafe.Pointer(abi.FuncPCABI0(raise_trampoline)), unsafe.Pointer(&sig))
+}
+func raise_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func pthread_self() (t pthread) {
+	libcCall(unsafe.Pointer(abi.FuncPCABI0(pthread_self_trampoline)), unsafe.Pointer(&t))
+	return
+}
+func pthread_self_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func pthread_kill(t pthread, sig uint32) {
+	libcCall(unsafe.Pointer(abi.FuncPCABI0(pthread_kill_trampoline)), unsafe.Pointer(&t))
+	return
+}
+func pthread_kill_trampoline()
+
+// mmap is used to do low-level memory allocation via mmap. Don't allow stack
+// splits, since this function (used by sysAlloc) is called in a lot of low-level
+// parts of the runtime and callers often assume it won't acquire any locks.
+//
+//go:nosplit
+func mmap(addr unsafe.Pointer, n uintptr, prot, flags, fd int32, off uint32) (unsafe.Pointer, int) {
+	args := struct {
+		addr            unsafe.Pointer
+		n               uintptr
+		prot, flags, fd int32
+		off             uint32
+		ret1            unsafe.Pointer
+		ret2            int
+	}{addr, n, prot, flags, fd, off, nil, 0}
+	libcCall(unsafe.Pointer(abi.FuncPCABI0(mmap_trampoline)), unsafe.Pointer(&args))
+	return args.ret1, args.ret2
+}
+func mmap_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func munmap(addr unsafe.Pointer, n uintptr) {
+	libcCall(unsafe.Pointer(abi.FuncPCABI0(munmap_trampoline)), unsafe.Pointer(&addr))
+	KeepAlive(addr) // Just for consistency. Hopefully addr is not a Go address.
+}
+func munmap_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func madvise(addr unsafe.Pointer, n uintptr, flags int32) {
+	libcCall(unsafe.Pointer(abi.FuncPCABI0(madvise_trampoline)), unsafe.Pointer(&addr))
+	KeepAlive(addr) // Just for consistency. Hopefully addr is not a Go address.
+}
+func madvise_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func mlock(addr unsafe.Pointer, n uintptr) {
+	libcCall(unsafe.Pointer(abi.FuncPCABI0(mlock_trampoline)), unsafe.Pointer(&addr))
+	KeepAlive(addr) // Just for consistency. Hopefully addr is not a Go address.
+}
+func mlock_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func read(fd int32, p unsafe.Pointer, n int32) int32 {
+	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(read_trampoline)), unsafe.Pointer(&fd))
+	KeepAlive(p)
+	return ret
+}
+func read_trampoline()
+
+func pipe() (r, w int32, errno int32) {
+	var p [2]int32
+	errno = libcCall(unsafe.Pointer(abi.FuncPCABI0(pipe_trampoline)), noescape(unsafe.Pointer(&p)))
+	return p[0], p[1], errno
+}
+func pipe_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func closefd(fd int32) int32 {
+	return libcCall(unsafe.Pointer(abi.FuncPCABI0(close_trampoline)), unsafe.Pointer(&fd))
+}
+func close_trampoline()
+
+// This is exported via linkname to assembly in runtime/cgo.
+//
+//go:nosplit
+//go:cgo_unsafe_args
+//go:linkname exit
+func exit(code int32) {
+	libcCall(unsafe.Pointer(abi.FuncPCABI0(exit_trampoline)), unsafe.Pointer(&code))
+}
+func exit_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func usleep(usec uint32) {
+	libcCall(unsafe.Pointer(abi.FuncPCABI0(usleep_trampoline)), unsafe.Pointer(&usec))
+}
+func usleep_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func usleep_no_g(usec uint32) {
+	asmcgocall_no_g(unsafe.Pointer(abi.FuncPCABI0(usleep_trampoline)), unsafe.Pointer(&usec))
+}
+
+//go:nosplit
+//go:cgo_unsafe_args
+func write1(fd uintptr, p unsafe.Pointer, n int32) int32 {
+	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(write_trampoline)), unsafe.Pointer(&fd))
+	KeepAlive(p)
+	return ret
+}
+func write_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func open(name *byte, mode, perm int32) (ret int32) {
+	ret = libcCall(unsafe.Pointer(abi.FuncPCABI0(open_trampoline)), unsafe.Pointer(&name))
+	KeepAlive(name)
+	return
+}
+func open_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func nanotime1() int64 {
+	var r struct {
+		t            int64  // raw timer
+		numer, denom uint32 // conversion factors. nanoseconds = t * numer / denom.
+	}
+	libcCall(unsafe.Pointer(abi.FuncPCABI0(nanotime_trampoline)), unsafe.Pointer(&r))
+	// Note: Apple seems unconcerned about overflow here. See
+	// https://developer.apple.com/library/content/qa/qa1398/_index.html
+	// Note also, numer == denom == 1 is common.
+	t := r.t
+	if r.numer != 1 {
+		t *= int64(r.numer)
+	}
+	if r.denom != 1 {
+		t /= int64(r.denom)
+	}
+	return t
+}
+func nanotime_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func walltime() (int64, int32) {
+	var t timespec
+	libcCall(unsafe.Pointer(abi.FuncPCABI0(walltime_trampoline)), unsafe.Pointer(&t))
+	return t.tv_sec, int32(t.tv_nsec)
+}
+func walltime_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func sigaction(sig uint32, new *usigactiont, old *usigactiont) {
+	libcCall(unsafe.Pointer(abi.FuncPCABI0(sigaction_trampoline)), unsafe.Pointer(&sig))
+	KeepAlive(new)
+	KeepAlive(old)
+}
+func sigaction_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func sigprocmask(how uint32, new *sigset, old *sigset) {
+	libcCall(unsafe.Pointer(abi.FuncPCABI0(sigprocmask_trampoline)), unsafe.Pointer(&how))
+	KeepAlive(new)
+	KeepAlive(old)
+}
+func sigprocmask_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func sigaltstack(new *stackt, old *stackt) {
+	if new != nil && new.ss_flags&_SS_DISABLE != 0 && new.ss_size == 0 {
+		// Despite the fact that Darwin's sigaltstack man page says it ignores the size
+		// when SS_DISABLE is set, it doesn't. sigaltstack returns ENOMEM
+		// if we don't give it a reasonable size.
+		// ref: http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20140421/214296.html
+		new.ss_size = 32768
+	}
+	libcCall(unsafe.Pointer(abi.FuncPCABI0(sigaltstack_trampoline)), unsafe.Pointer(&new))
+	KeepAlive(new)
+	KeepAlive(old)
+}
+func sigaltstack_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func raiseproc(sig uint32) {
+	libcCall(unsafe.Pointer(abi.FuncPCABI0(raiseproc_trampoline)), unsafe.Pointer(&sig))
+}
+func raiseproc_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func setitimer(mode int32, new, old *itimerval) {
+	libcCall(unsafe.Pointer(abi.FuncPCABI0(setitimer_trampoline)), unsafe.Pointer(&mode))
+	KeepAlive(new)
+	KeepAlive(old)
+}
+func setitimer_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func sysctl(mib *uint32, miblen uint32, oldp *byte, oldlenp *uintptr, newp *byte, newlen uintptr) int32 {
+	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(sysctl_trampoline)), unsafe.Pointer(&mib))
+	KeepAlive(mib)
+	KeepAlive(oldp)
+	KeepAlive(oldlenp)
+	KeepAlive(newp)
+	return ret
+}
+func sysctl_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func sysctlbyname(name *byte, oldp *byte, oldlenp *uintptr, newp *byte, newlen uintptr) int32 {
+	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(sysctlbyname_trampoline)), unsafe.Pointer(&name))
+	KeepAlive(name)
+	KeepAlive(oldp)
+	KeepAlive(oldlenp)
+	KeepAlive(newp)
+	return ret
+}
+func sysctlbyname_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func fcntl(fd, cmd, arg int32) int32 {
+	return libcCall(unsafe.Pointer(abi.FuncPCABI0(fcntl_trampoline)), unsafe.Pointer(&fd))
+}
+func fcntl_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func kqueue() int32 {
+	v := libcCall(unsafe.Pointer(abi.FuncPCABI0(kqueue_trampoline)), nil)
+	return v
+}
+func kqueue_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func kevent(kq int32, ch *keventt, nch int32, ev *keventt, nev int32, ts *timespec) int32 {
+	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(kevent_trampoline)), unsafe.Pointer(&kq))
+	KeepAlive(ch)
+	KeepAlive(ev)
+	KeepAlive(ts)
+	return ret
+}
+func kevent_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func pthread_mutex_init(m *pthreadmutex, attr *pthreadmutexattr) int32 {
+	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(pthread_mutex_init_trampoline)), unsafe.Pointer(&m))
+	KeepAlive(m)
+	KeepAlive(attr)
+	return ret
+}
+func pthread_mutex_init_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func pthread_mutex_lock(m *pthreadmutex) int32 {
+	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(pthread_mutex_lock_trampoline)), unsafe.Pointer(&m))
+	KeepAlive(m)
+	return ret
+}
+func pthread_mutex_lock_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func pthread_mutex_unlock(m *pthreadmutex) int32 {
+	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(pthread_mutex_unlock_trampoline)), unsafe.Pointer(&m))
+	KeepAlive(m)
+	return ret
+}
+func pthread_mutex_unlock_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func pthread_cond_init(c *pthreadcond, attr *pthreadcondattr) int32 {
+	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(pthread_cond_init_trampoline)), unsafe.Pointer(&c))
+	KeepAlive(c)
+	KeepAlive(attr)
+	return ret
+}
+func pthread_cond_init_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func pthread_cond_wait(c *pthreadcond, m *pthreadmutex) int32 {
+	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(pthread_cond_wait_trampoline)), unsafe.Pointer(&c))
+	KeepAlive(c)
+	KeepAlive(m)
+	return ret
+}
+func pthread_cond_wait_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func pthread_cond_timedwait_relative_np(c *pthreadcond, m *pthreadmutex, t *timespec) int32 {
+	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(pthread_cond_timedwait_relative_np_trampoline)), unsafe.Pointer(&c))
+	KeepAlive(c)
+	KeepAlive(m)
+	KeepAlive(t)
+	return ret
+}
+func pthread_cond_timedwait_relative_np_trampoline()
+
+//go:nosplit
+//go:cgo_unsafe_args
+func pthread_cond_signal(c *pthreadcond) int32 {
+	ret := libcCall(unsafe.Pointer(abi.FuncPCABI0(pthread_cond_signal_trampoline)), unsafe.Pointer(&c))
+	KeepAlive(c)
+	return ret
+}
+func pthread_cond_signal_trampoline()
+
+// Not used on Darwin, but must be defined.
+func exitThread(wait *uint32) {
+}
+
+//go:nosplit
+func closeonexec(fd int32) {
+	fcntl(fd, _F_SETFD, _FD_CLOEXEC)
+}
+
+//go:nosplit
+func setNonblock(fd int32) {
+	flags := fcntl(fd, _F_GETFL, 0)
+	fcntl(fd, _F_SETFL, flags|_O_NONBLOCK)
+}
+
+// Tell the linker that the libc_* functions are to be found
+// in a system library, with the libc_ prefix missing.
+
+//go:cgo_import_dynamic libc_pthread_attr_init pthread_attr_init "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_pthread_attr_getstacksize pthread_attr_getstacksize "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_pthread_attr_setdetachstate pthread_attr_setdetachstate "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_pthread_create pthread_create "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_pthread_self pthread_self "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_pthread_kill pthread_kill "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_exit _exit "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_raise raise "/usr/lib/libSystem.B.dylib"
+
+//go:cgo_import_dynamic libc_open open "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_close close "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_read read "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_write write "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_pipe pipe "/usr/lib/libSystem.B.dylib"
+
+//go:cgo_import_dynamic libc_mmap mmap "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_munmap munmap "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_madvise madvise "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_mlock mlock "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_error __error "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_usleep usleep "/usr/lib/libSystem.B.dylib"
+
+//go:cgo_import_dynamic libc_mach_timebase_info mach_timebase_info "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_mach_absolute_time mach_absolute_time "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_clock_gettime clock_gettime "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_sigaction sigaction "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_pthread_sigmask pthread_sigmask "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_sigaltstack sigaltstack "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_getpid getpid "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_kill kill "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_setitimer setitimer "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_sysctl sysctl "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_sysctlbyname sysctlbyname "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_fcntl fcntl "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_kqueue kqueue "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_kevent kevent "/usr/lib/libSystem.B.dylib"
+
+//go:cgo_import_dynamic libc_pthread_mutex_init pthread_mutex_init "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_pthread_mutex_lock pthread_mutex_lock "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_pthread_mutex_unlock pthread_mutex_unlock "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_pthread_cond_init pthread_cond_init "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_pthread_cond_wait pthread_cond_wait "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_pthread_cond_timedwait_relative_np pthread_cond_timedwait_relative_np "/usr/lib/libSystem.B.dylib"
+//go:cgo_import_dynamic libc_pthread_cond_signal pthread_cond_signal "/usr/lib/libSystem.B.dylib"
diff --git a/contrib/go/_std_1.19/src/runtime/sys_darwin_amd64.s b/contrib/go/_std_1.19/src/runtime/sys_darwin_amd64.s
new file mode 100644
index 0000000000..ba81fcc35c
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/sys_darwin_amd64.s
@@ -0,0 +1,867 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// System calls and other sys.stuff for AMD64, Darwin
+// System calls are implemented in libSystem, this file contains
+// trampolines that convert from Go to C calling convention.
+
+#include "go_asm.h"
+#include "go_tls.h"
+#include "textflag.h"
+#include "cgo/abi_amd64.h"
+
+#define CLOCK_REALTIME		0
+
+// Exit the entire program (like C exit)
+TEXT runtime·exit_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVL	0(DI), DI		// arg 1 exit status
+	CALL	libc_exit(SB)
+	MOVL	$0xf1, 0xf1  // crash
+	POPQ	BP
+	RET
+
+TEXT runtime·open_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVL	8(DI), SI		// arg 2 flags
+	MOVL	12(DI), DX		// arg 3 mode
+	MOVQ	0(DI), DI		// arg 1 pathname
+	XORL	AX, AX			// vararg: say "no float args"
+	CALL	libc_open(SB)
+	POPQ	BP
+	RET
+
+TEXT runtime·close_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVL	0(DI), DI		// arg 1 fd
+	CALL	libc_close(SB)
+	POPQ	BP
+	RET
+
+TEXT runtime·read_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVQ	8(DI), SI		// arg 2 buf
+	MOVL	16(DI), DX		// arg 3 count
+	MOVL	0(DI), DI		// arg 1 fd
+	CALL	libc_read(SB)
+	TESTL	AX, AX
+	JGE	noerr
+	CALL	libc_error(SB)
+	MOVL	(AX), AX
+	NEGL	AX			// caller expects negative errno value
+noerr:
+	POPQ	BP
+	RET
+
+TEXT runtime·write_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVQ	8(DI), SI		// arg 2 buf
+	MOVL	16(DI), DX		// arg 3 count
+	MOVQ	0(DI), DI		// arg 1 fd
+	CALL	libc_write(SB)
+	TESTL	AX, AX
+	JGE	noerr
+	CALL	libc_error(SB)
+	MOVL	(AX), AX
+	NEGL	AX			// caller expects negative errno value
+noerr:
+	POPQ	BP
+	RET
+
+TEXT runtime·pipe_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	CALL	libc_pipe(SB)		// pointer already in DI
+	TESTL	AX, AX
+	JEQ	3(PC)
+	CALL	libc_error(SB)		// return negative errno value
+	NEGL	AX
+	POPQ	BP
+	RET
+
+TEXT runtime·setitimer_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVQ	8(DI), SI		// arg 2 new
+	MOVQ	16(DI), DX		// arg 3 old
+	MOVL	0(DI), DI		// arg 1 which
+	CALL	libc_setitimer(SB)
+	POPQ	BP
+	RET
+
+TEXT runtime·madvise_trampoline(SB), NOSPLIT, $0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVQ	8(DI), SI	// arg 2 len
+	MOVL	16(DI), DX	// arg 3 advice
+	MOVQ	0(DI), DI	// arg 1 addr
+	CALL	libc_madvise(SB)
+	// ignore failure - maybe pages are locked
+	POPQ	BP
+	RET
+
+TEXT runtime·mlock_trampoline(SB), NOSPLIT, $0
+	UNDEF // unimplemented
+
+GLOBL timebase<>(SB),NOPTR,$(machTimebaseInfo__size)
+
+TEXT runtime·nanotime_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVQ	DI, BX
+	CALL	libc_mach_absolute_time(SB)
+	MOVQ	AX, 0(BX)
+	MOVL	timebase<>+machTimebaseInfo_numer(SB), SI
+	MOVL	timebase<>+machTimebaseInfo_denom(SB), DI // atomic read
+	TESTL	DI, DI
+	JNE	initialized
+
+	SUBQ	$(machTimebaseInfo__size+15)/16*16, SP
+	MOVQ	SP, DI
+	CALL	libc_mach_timebase_info(SB)
+	MOVL	machTimebaseInfo_numer(SP), SI
+	MOVL	machTimebaseInfo_denom(SP), DI
+	ADDQ	$(machTimebaseInfo__size+15)/16*16, SP
+
+	MOVL	SI, timebase<>+machTimebaseInfo_numer(SB)
+	MOVL	DI, AX
+	XCHGL	AX, timebase<>+machTimebaseInfo_denom(SB) // atomic write
+
+initialized:
+	MOVL	SI, 8(BX)
+	MOVL	DI, 12(BX)
+	MOVQ	BP, SP
+	POPQ	BP
+	RET
+
+TEXT runtime·walltime_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP			// make a frame; keep stack aligned
+	MOVQ	SP, BP
+	MOVQ	DI, SI			// arg 2 timespec
+	MOVL	$CLOCK_REALTIME, DI	// arg 1 clock_id
+	CALL	libc_clock_gettime(SB)
+	POPQ	BP
+	RET
+
+TEXT runtime·sigaction_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVQ	8(DI), SI		// arg 2 new
+	MOVQ	16(DI), DX		// arg 3 old
+	MOVL	0(DI), DI		// arg 1 sig
+	CALL	libc_sigaction(SB)
+	TESTL	AX, AX
+	JEQ	2(PC)
+	MOVL	$0xf1, 0xf1  // crash
+	POPQ	BP
+	RET
+
+TEXT runtime·sigprocmask_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVQ	8(DI), SI	// arg 2 new
+	MOVQ	16(DI), DX	// arg 3 old
+	MOVL	0(DI), DI	// arg 1 how
+	CALL	libc_pthread_sigmask(SB)
+	TESTL	AX, AX
+	JEQ	2(PC)
+	MOVL	$0xf1, 0xf1  // crash
+	POPQ	BP
+	RET
+
+TEXT runtime·sigaltstack_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVQ	8(DI), SI		// arg 2 old
+	MOVQ	0(DI), DI		// arg 1 new
+	CALL	libc_sigaltstack(SB)
+	TESTQ	AX, AX
+	JEQ	2(PC)
+	MOVL	$0xf1, 0xf1  // crash
+	POPQ	BP
+	RET
+
+TEXT runtime·raiseproc_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVL	0(DI), BX	// signal
+	CALL	libc_getpid(SB)
+	MOVL	AX, DI		// arg 1 pid
+	MOVL	BX, SI		// arg 2 signal
+	CALL	libc_kill(SB)
+	POPQ	BP
+	RET
+
+TEXT runtime·sigfwd(SB),NOSPLIT,$0-32
+	MOVQ	fn+0(FP),    AX
+	MOVL	sig+8(FP),   DI
+	MOVQ	info+16(FP), SI
+	MOVQ	ctx+24(FP),  DX
+	PUSHQ	BP
+	MOVQ	SP, BP
+	ANDQ	$~15, SP     // alignment for x86_64 ABI
+	CALL	AX
+	MOVQ	BP, SP
+	POPQ	BP
+	RET
+
+// This is the function registered during sigaction and is invoked when
+// a signal is received. It just redirects to the Go function sigtrampgo.
+// Called using C ABI.
+TEXT runtime·sigtramp(SB),NOSPLIT|TOPFRAME,$0
+	// Transition from C ABI to Go ABI.
+	PUSH_REGS_HOST_TO_ABI0()
+
+	// Set up ABIInternal environment: g in R14, cleared X15.
+	get_tls(R12)
+	MOVQ	g(R12), R14
+	PXOR	X15, X15
+
+	// Reserve space for spill slots.
+	NOP	SP		// disable vet stack checking
+	ADJSP   $24
+
+	// Call into the Go signal handler
+	MOVQ	DI, AX	// sig
+	MOVQ	SI, BX	// info
+	MOVQ	DX, CX	// ctx
+	CALL	·sigtrampgo<ABIInternal>(SB)
+
+	ADJSP	$-24
+
+	POP_REGS_HOST_TO_ABI0()
+	RET
+
+// Called using C ABI.
+TEXT runtime·sigprofNonGoWrapper<>(SB),NOSPLIT,$0
+	// Transition from C ABI to Go ABI.
+	PUSH_REGS_HOST_TO_ABI0()
+
+	// Call into the Go signal handler
+	NOP	SP		// disable vet stack checking
+	ADJSP	$24
+	MOVL	DI, 0(SP)	// sig
+	MOVQ	SI, 8(SP)	// info
+	MOVQ	DX, 16(SP)	// ctx
+	CALL	·sigprofNonGo(SB)
+	ADJSP	$-24
+
+	POP_REGS_HOST_TO_ABI0()
+	RET
+
+// Used instead of sigtramp in programs that use cgo.
+// Arguments from kernel are in DI, SI, DX.
+TEXT runtime·cgoSigtramp(SB),NOSPLIT,$0
+	// If no traceback function, do usual sigtramp.
+	MOVQ	runtime·cgoTraceback(SB), AX
+	TESTQ	AX, AX
+	JZ	sigtramp
+
+	// If no traceback support function, which means that
+	// runtime/cgo was not linked in, do usual sigtramp.
+	MOVQ	_cgo_callers(SB), AX
+	TESTQ	AX, AX
+	JZ	sigtramp
+
+	// Figure out if we are currently in a cgo call.
+	// If not, just do usual sigtramp.
+	get_tls(CX)
+	MOVQ	g(CX),AX
+	TESTQ	AX, AX
+	JZ	sigtrampnog     // g == nil
+	MOVQ	g_m(AX), AX
+	TESTQ	AX, AX
+	JZ	sigtramp        // g.m == nil
+	MOVL	m_ncgo(AX), CX
+	TESTL	CX, CX
+	JZ	sigtramp        // g.m.ncgo == 0
+	MOVQ	m_curg(AX), CX
+	TESTQ	CX, CX
+	JZ	sigtramp        // g.m.curg == nil
+	MOVQ	g_syscallsp(CX), CX
+	TESTQ	CX, CX
+	JZ	sigtramp        // g.m.curg.syscallsp == 0
+	MOVQ	m_cgoCallers(AX), R8
+	TESTQ	R8, R8
+	JZ	sigtramp        // g.m.cgoCallers == nil
+	MOVL	m_cgoCallersUse(AX), CX
+	TESTL	CX, CX
+	JNZ	sigtramp	// g.m.cgoCallersUse != 0
+
+	// Jump to a function in runtime/cgo.
+	// That function, written in C, will call the user's traceback
+	// function with proper unwind info, and will then call back here.
+	// The first three arguments, and the fifth, are already in registers.
+	// Set the two remaining arguments now.
+	MOVQ	runtime·cgoTraceback(SB), CX
+	MOVQ	$runtime·sigtramp(SB), R9
+	MOVQ	_cgo_callers(SB), AX
+	JMP	AX
+
+sigtramp:
+	JMP	runtime·sigtramp(SB)
+
+sigtrampnog:
+	// Signal arrived on a non-Go thread. If this is SIGPROF, get a
+	// stack trace.
+	CMPL	DI, $27 // 27 == SIGPROF
+	JNZ	sigtramp
+
+	// Lock sigprofCallersUse.
+	MOVL	$0, AX
+	MOVL	$1, CX
+	MOVQ	$runtime·sigprofCallersUse(SB), R11
+	LOCK
+	CMPXCHGL	CX, 0(R11)
+	JNZ	sigtramp  // Skip stack trace if already locked.
+
+	// Jump to the traceback function in runtime/cgo.
+	// It will call back to sigprofNonGo, via sigprofNonGoWrapper, to convert
+	// the arguments to the Go calling convention.
+	// First three arguments to traceback function are in registers already.
+	MOVQ	runtime·cgoTraceback(SB), CX
+	MOVQ	$runtime·sigprofCallers(SB), R8
+	MOVQ	$runtime·sigprofNonGoWrapper<>(SB), R9
+	MOVQ	_cgo_callers(SB), AX
+	JMP	AX
+
+TEXT runtime·mmap_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP			// make a frame; keep stack aligned
+	MOVQ	SP, BP
+	MOVQ	DI, BX
+	MOVQ	0(BX), DI		// arg 1 addr
+	MOVQ	8(BX), SI		// arg 2 len
+	MOVL	16(BX), DX		// arg 3 prot
+	MOVL	20(BX), CX		// arg 4 flags
+	MOVL	24(BX), R8		// arg 5 fid
+	MOVL	28(BX), R9		// arg 6 offset
+	CALL	libc_mmap(SB)
+	XORL	DX, DX
+	CMPQ	AX, $-1
+	JNE	ok
+	CALL	libc_error(SB)
+	MOVLQSX	(AX), DX		// errno
+	XORL	AX, AX
+ok:
+	MOVQ	AX, 32(BX)
+	MOVQ	DX, 40(BX)
+	POPQ	BP
+	RET
+
+TEXT runtime·munmap_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVQ	8(DI), SI		// arg 2 len
+	MOVQ	0(DI), DI		// arg 1 addr
+	CALL	libc_munmap(SB)
+	TESTQ	AX, AX
+	JEQ	2(PC)
+	MOVL	$0xf1, 0xf1  // crash
+	POPQ	BP
+	RET
+
+TEXT runtime·usleep_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVL	0(DI), DI	// arg 1 usec
+	CALL	libc_usleep(SB)
+	POPQ	BP
+	RET
+
+TEXT runtime·settls(SB),NOSPLIT,$32
+	// Nothing to do on Darwin, pthread already set thread-local storage up.
+	RET
+
+TEXT runtime·sysctl_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVL	8(DI), SI		// arg 2 miblen
+	MOVQ	16(DI), DX		// arg 3 oldp
+	MOVQ	24(DI), CX		// arg 4 oldlenp
+	MOVQ	32(DI), R8		// arg 5 newp
+	MOVQ	40(DI), R9		// arg 6 newlen
+	MOVQ	0(DI), DI		// arg 1 mib
+	CALL	libc_sysctl(SB)
+	POPQ	BP
+	RET
+
+TEXT runtime·sysctlbyname_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVQ	8(DI), SI		// arg 2 oldp
+	MOVQ	16(DI), DX		// arg 3 oldlenp
+	MOVQ	24(DI), CX		// arg 4 newp
+	MOVQ	32(DI), R8		// arg 5 newlen
+	MOVQ	0(DI), DI		// arg 1 name
+	CALL	libc_sysctlbyname(SB)
+	POPQ	BP
+	RET
+
+TEXT runtime·kqueue_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	CALL	libc_kqueue(SB)
+	POPQ	BP
+	RET
+
+TEXT runtime·kevent_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVQ	8(DI), SI		// arg 2 keventt
+	MOVL	16(DI), DX		// arg 3 nch
+	MOVQ	24(DI), CX		// arg 4 ev
+	MOVL	32(DI), R8		// arg 5 nev
+	MOVQ	40(DI), R9		// arg 6 ts
+	MOVL	0(DI), DI		// arg 1 kq
+	CALL	libc_kevent(SB)
+	CMPL	AX, $-1
+	JNE	ok
+	CALL	libc_error(SB)
+	MOVLQSX	(AX), AX		// errno
+	NEGQ	AX			// caller wants it as a negative error code
+ok:
+	POPQ	BP
+	RET
+
+TEXT runtime·fcntl_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVL	4(DI), SI		// arg 2 cmd
+	MOVL	8(DI), DX		// arg 3 arg
+	MOVL	0(DI), DI		// arg 1 fd
+	XORL	AX, AX			// vararg: say "no float args"
+	CALL	libc_fcntl(SB)
+	POPQ	BP
+	RET
+
+// mstart_stub is the first function executed on a new thread started by pthread_create.
+// It just does some low-level setup and then calls mstart.
+// Note: called with the C calling convention.
+TEXT runtime·mstart_stub(SB),NOSPLIT,$0
+	// DI points to the m.
+	// We are already on m's g0 stack.
+
+	// Transition from C ABI to Go ABI.
+	PUSH_REGS_HOST_TO_ABI0()
+
+	MOVQ	m_g0(DI), DX // g
+
+	// Initialize TLS entry.
+	// See cmd/link/internal/ld/sym.go:computeTLSOffset.
+	MOVQ	DX, 0x30(GS)
+
+	CALL	runtime·mstart(SB)
+
+	POP_REGS_HOST_TO_ABI0()
+
+	// Go is all done with this OS thread.
+	// Tell pthread everything is ok (we never join with this thread, so
+	// the value here doesn't really matter).
+	XORL	AX, AX
+	RET
+
+// These trampolines help convert from Go calling convention to C calling convention.
+// They should be called with asmcgocall.
+// A pointer to the arguments is passed in DI.
+// A single int32 result is returned in AX.
+// (For more results, make an args/results structure.)
+TEXT runtime·pthread_attr_init_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP	// make frame, keep stack 16-byte aligned.
+	MOVQ	SP, BP
+	MOVQ	0(DI), DI // arg 1 attr
+	CALL	libc_pthread_attr_init(SB)
+	POPQ	BP
+	RET
+
+TEXT runtime·pthread_attr_getstacksize_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVQ	8(DI), SI	// arg 2 size
+	MOVQ	0(DI), DI	// arg 1 attr
+	CALL	libc_pthread_attr_getstacksize(SB)
+	POPQ	BP
+	RET
+
+TEXT runtime·pthread_attr_setdetachstate_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVQ	8(DI), SI	// arg 2 state
+	MOVQ	0(DI), DI	// arg 1 attr
+	CALL	libc_pthread_attr_setdetachstate(SB)
+	POPQ	BP
+	RET
+
+TEXT runtime·pthread_create_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	SUBQ	$16, SP
+	MOVQ	0(DI), SI	// arg 2 attr
+	MOVQ	8(DI), DX	// arg 3 start
+	MOVQ	16(DI), CX	// arg 4 arg
+	MOVQ	SP, DI		// arg 1 &threadid (which we throw away)
+	CALL	libc_pthread_create(SB)
+	MOVQ	BP, SP
+	POPQ	BP
+	RET
+
+TEXT runtime·raise_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVL	0(DI), DI	// arg 1 signal
+	CALL	libc_raise(SB)
+	POPQ	BP
+	RET
+
+TEXT runtime·pthread_mutex_init_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVQ	8(DI), SI	// arg 2 attr
+	MOVQ	0(DI), DI	// arg 1 mutex
+	CALL	libc_pthread_mutex_init(SB)
+	POPQ	BP
+	RET
+
+TEXT runtime·pthread_mutex_lock_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVQ	0(DI), DI	// arg 1 mutex
+	CALL	libc_pthread_mutex_lock(SB)
+	POPQ	BP
+	RET
+
+TEXT runtime·pthread_mutex_unlock_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVQ	0(DI), DI	// arg 1 mutex
+	CALL	libc_pthread_mutex_unlock(SB)
+	POPQ	BP
+	RET
+
+TEXT runtime·pthread_cond_init_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVQ	8(DI), SI	// arg 2 attr
+	MOVQ	0(DI), DI	// arg 1 cond
+	CALL	libc_pthread_cond_init(SB)
+	POPQ	BP
+	RET
+
+TEXT runtime·pthread_cond_wait_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVQ	8(DI), SI	// arg 2 mutex
+	MOVQ	0(DI), DI	// arg 1 cond
+	CALL	libc_pthread_cond_wait(SB)
+	POPQ	BP
+	RET
+
+TEXT runtime·pthread_cond_timedwait_relative_np_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVQ	8(DI), SI	// arg 2 mutex
+	MOVQ	16(DI), DX	// arg 3 timeout
+	MOVQ	0(DI), DI	// arg 1 cond
+	CALL	libc_pthread_cond_timedwait_relative_np(SB)
+	POPQ	BP
+	RET
+
+TEXT runtime·pthread_cond_signal_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVQ	0(DI), DI	// arg 1 cond
+	CALL	libc_pthread_cond_signal(SB)
+	POPQ	BP
+	RET
+
+TEXT runtime·pthread_self_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVQ	DI, BX		// BX is caller-save
+	CALL	libc_pthread_self(SB)
+	MOVQ	AX, 0(BX)	// return value
+	POPQ	BP
+	RET
+
+TEXT runtime·pthread_kill_trampoline(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	MOVQ	8(DI), SI	// arg 2 sig
+	MOVQ	0(DI), DI	// arg 1 thread
+	CALL	libc_pthread_kill(SB)
+	POPQ	BP
+	RET
+
+// syscall calls a function in libc on behalf of the syscall package.
+// syscall takes a pointer to a struct like:
+// struct {
+//	fn    uintptr
+//	a1    uintptr
+//	a2    uintptr
+//	a3    uintptr
+//	r1    uintptr
+//	r2    uintptr
+//	err   uintptr
+// }
+// syscall must be called on the g0 stack with the
+// C calling convention (use libcCall).
+//
+// syscall expects a 32-bit result and tests for 32-bit -1
+// to decide there was an error.
+TEXT runtime·syscall(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	SUBQ	$16, SP
+	MOVQ	(0*8)(DI), CX // fn
+	MOVQ	(2*8)(DI), SI // a2
+	MOVQ	(3*8)(DI), DX // a3
+	MOVQ	DI, (SP)
+	MOVQ	(1*8)(DI), DI // a1
+	XORL	AX, AX	      // vararg: say "no float args"
+
+	CALL	CX
+
+	MOVQ	(SP), DI
+	MOVQ	AX, (4*8)(DI) // r1
+	MOVQ	DX, (5*8)(DI) // r2
+
+	// Standard libc functions return -1 on error
+	// and set errno.
+	CMPL	AX, $-1	      // Note: high 32 bits are junk
+	JNE	ok
+
+	// Get error code from libc.
+	CALL	libc_error(SB)
+	MOVLQSX	(AX), AX
+	MOVQ	(SP), DI
+	MOVQ	AX, (6*8)(DI) // err
+
+ok:
+	XORL	AX, AX        // no error (it's ignored anyway)
+	MOVQ	BP, SP
+	POPQ	BP
+	RET
+
+// syscallX calls a function in libc on behalf of the syscall package.
+// syscallX takes a pointer to a struct like:
+// struct {
+//	fn    uintptr
+//	a1    uintptr
+//	a2    uintptr
+//	a3    uintptr
+//	r1    uintptr
+//	r2    uintptr
+//	err   uintptr
+// }
+// syscallX must be called on the g0 stack with the
+// C calling convention (use libcCall).
+//
+// syscallX is like syscall but expects a 64-bit result
+// and tests for 64-bit -1 to decide there was an error.
+TEXT runtime·syscallX(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	SUBQ	$16, SP
+	MOVQ	(0*8)(DI), CX // fn
+	MOVQ	(2*8)(DI), SI // a2
+	MOVQ	(3*8)(DI), DX // a3
+	MOVQ	DI, (SP)
+	MOVQ	(1*8)(DI), DI // a1
+	XORL	AX, AX	      // vararg: say "no float args"
+
+	CALL	CX
+
+	MOVQ	(SP), DI
+	MOVQ	AX, (4*8)(DI) // r1
+	MOVQ	DX, (5*8)(DI) // r2
+
+	// Standard libc functions return -1 on error
+	// and set errno.
+	CMPQ	AX, $-1
+	JNE	ok
+
+	// Get error code from libc.
+	CALL	libc_error(SB)
+	MOVLQSX	(AX), AX
+	MOVQ	(SP), DI
+	MOVQ	AX, (6*8)(DI) // err
+
+ok:
+	XORL	AX, AX        // no error (it's ignored anyway)
+	MOVQ	BP, SP
+	POPQ	BP
+	RET
+
+// syscallPtr is like syscallX except that the libc function reports an
+// error by returning NULL and setting errno.
+TEXT runtime·syscallPtr(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	SUBQ	$16, SP
+	MOVQ	(0*8)(DI), CX // fn
+	MOVQ	(2*8)(DI), SI // a2
+	MOVQ	(3*8)(DI), DX // a3
+	MOVQ	DI, (SP)
+	MOVQ	(1*8)(DI), DI // a1
+	XORL	AX, AX	      // vararg: say "no float args"
+
+	CALL	CX
+
+	MOVQ	(SP), DI
+	MOVQ	AX, (4*8)(DI) // r1
+	MOVQ	DX, (5*8)(DI) // r2
+
+	// syscallPtr libc functions return NULL on error
+	// and set errno.
+	TESTQ	AX, AX
+	JNE	ok
+
+	// Get error code from libc.
+	CALL	libc_error(SB)
+	MOVLQSX	(AX), AX
+	MOVQ	(SP), DI
+	MOVQ	AX, (6*8)(DI) // err
+
+ok:
+	XORL	AX, AX        // no error (it's ignored anyway)
+	MOVQ	BP, SP
+	POPQ	BP
+	RET
+
+// syscall6 calls a function in libc on behalf of the syscall package.
+// syscall6 takes a pointer to a struct like:
+// struct {
+//	fn    uintptr
+//	a1    uintptr
+//	a2    uintptr
+//	a3    uintptr
+//	a4    uintptr
+//	a5    uintptr
+//	a6    uintptr
+//	r1    uintptr
+//	r2    uintptr
+//	err   uintptr
+// }
+// syscall6 must be called on the g0 stack with the
+// C calling convention (use libcCall).
+//
+// syscall6 expects a 32-bit result and tests for 32-bit -1
+// to decide there was an error.
+TEXT runtime·syscall6(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	SUBQ	$16, SP
+	MOVQ	(0*8)(DI), R11// fn
+	MOVQ	(2*8)(DI), SI // a2
+	MOVQ	(3*8)(DI), DX // a3
+	MOVQ	(4*8)(DI), CX // a4
+	MOVQ	(5*8)(DI), R8 // a5
+	MOVQ	(6*8)(DI), R9 // a6
+	MOVQ	DI, (SP)
+	MOVQ	(1*8)(DI), DI // a1
+	XORL	AX, AX	      // vararg: say "no float args"
+
+	CALL	R11
+
+	MOVQ	(SP), DI
+	MOVQ	AX, (7*8)(DI) // r1
+	MOVQ	DX, (8*8)(DI) // r2
+
+	CMPL	AX, $-1
+	JNE	ok
+
+	CALL	libc_error(SB)
+	MOVLQSX	(AX), AX
+	MOVQ	(SP), DI
+	MOVQ	AX, (9*8)(DI) // err
+
+ok:
+	XORL	AX, AX        // no error (it's ignored anyway)
+	MOVQ	BP, SP
+	POPQ	BP
+	RET
+
+// syscall6X calls a function in libc on behalf of the syscall package.
+// syscall6X takes a pointer to a struct like:
+// struct {
+//	fn    uintptr
+//	a1    uintptr
+//	a2    uintptr
+//	a3    uintptr
+//	a4    uintptr
+//	a5    uintptr
+//	a6    uintptr
+//	r1    uintptr
+//	r2    uintptr
+//	err   uintptr
+// }
+// syscall6X must be called on the g0 stack with the
+// C calling convention (use libcCall).
+//
+// syscall6X is like syscall6 but expects a 64-bit result
+// and tests for 64-bit -1 to decide there was an error.
+TEXT runtime·syscall6X(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	SUBQ	$16, SP
+	MOVQ	(0*8)(DI), R11// fn
+	MOVQ	(2*8)(DI), SI // a2
+	MOVQ	(3*8)(DI), DX // a3
+	MOVQ	(4*8)(DI), CX // a4
+	MOVQ	(5*8)(DI), R8 // a5
+	MOVQ	(6*8)(DI), R9 // a6
+	MOVQ	DI, (SP)
+	MOVQ	(1*8)(DI), DI // a1
+	XORL	AX, AX	      // vararg: say "no float args"
+
+	CALL	R11
+
+	MOVQ	(SP), DI
+	MOVQ	AX, (7*8)(DI) // r1
+	MOVQ	DX, (8*8)(DI) // r2
+
+	CMPQ	AX, $-1
+	JNE	ok
+
+	CALL	libc_error(SB)
+	MOVLQSX	(AX), AX
+	MOVQ	(SP), DI
+	MOVQ	AX, (9*8)(DI) // err
+
+ok:
+	XORL	AX, AX        // no error (it's ignored anyway)
+	MOVQ	BP, SP
+	POPQ	BP
+	RET
+
+// syscall_x509 is for crypto/x509. It is like syscall6 but does not check for errors,
+// takes 5 uintptrs and 1 float64, and only returns one value,
+// for use with standard C ABI functions.
+TEXT runtime·syscall_x509(SB),NOSPLIT,$0
+	PUSHQ	BP
+	MOVQ	SP, BP
+	SUBQ	$16, SP
+	MOVQ	(0*8)(DI), R11// fn
+	MOVQ	(2*8)(DI), SI // a2
+	MOVQ	(3*8)(DI), DX // a3
+	MOVQ	(4*8)(DI), CX // a4
+	MOVQ	(5*8)(DI), R8 // a5
+	MOVQ	(6*8)(DI), X0 // f1
+	MOVQ	DI, (SP)
+	MOVQ	(1*8)(DI), DI // a1
+	XORL	AX, AX	      // vararg: say "no float args"
+
+	CALL	R11
+
+	MOVQ	(SP), DI
+	MOVQ	AX, (7*8)(DI) // r1
+
+	XORL	AX, AX        // no error (it's ignored anyway)
+	MOVQ	BP, SP
+	POPQ	BP
+	RET
diff --git a/contrib/go/_std_1.19/src/runtime/sys_libc.go b/contrib/go/_std_1.19/src/runtime/sys_libc.go
new file mode 100644
index 0000000000..0c6f13ca9f
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/sys_libc.go
@@ -0,0 +1,54 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build darwin || (openbsd && !mips64)
+
+package runtime
+
+import "unsafe"
+
+// Call fn with arg as its argument. Return what fn returns.
+// fn is the raw pc value of the entry point of the desired function.
+// Switches to the system stack, if not already there.
+// Preserves the calling point as the location where a profiler traceback will begin.
+//
+//go:nosplit
+func libcCall(fn, arg unsafe.Pointer) int32 {
+	// Leave caller's PC/SP/G around for traceback.
+	gp := getg()
+	var mp *m
+	if gp != nil {
+		mp = gp.m
+	}
+	if mp != nil && mp.libcallsp == 0 {
+		mp.libcallg.set(gp)
+		mp.libcallpc = getcallerpc()
+		// sp must be the last, because once async cpu profiler finds
+		// all three values to be non-zero, it will use them
+		mp.libcallsp = getcallersp()
+	} else {
+		// Make sure we don't reset libcallsp. This makes
+		// libcCall reentrant; We remember the g/pc/sp for the
+		// first call on an M, until that libcCall instance
+		// returns.  Reentrance only matters for signals, as
+		// libc never calls back into Go.  The tricky case is
+		// where we call libcX from an M and record g/pc/sp.
+		// Before that call returns, a signal arrives on the
+		// same M and the signal handling code calls another
+		// libc function.  We don't want that second libcCall
+		// from within the handler to be recorded, and we
+		// don't want that call's completion to zero
+		// libcallsp.
+		// We don't need to set libcall* while we're in a sighandler
+		// (even if we're not currently in libc) because we block all
+		// signals while we're handling a signal. That includes the
+		// profile signal, which is the one that uses the libcall* info.
+		mp = nil
+	}
+	res := asmcgocall(fn, arg)
+	if mp != nil {
+		mp.libcallsp = 0
+	}
+	return res
+}
diff --git a/contrib/go/_std_1.19/src/runtime/sys_linux_amd64.s b/contrib/go/_std_1.19/src/runtime/sys_linux_amd64.s
new file mode 100644
index 0000000000..ca6ecb13eb
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/sys_linux_amd64.s
@@ -0,0 +1,757 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//
+// System calls and other sys.stuff for AMD64, Linux
+//
+
+#include "go_asm.h"
+#include "go_tls.h"
+#include "textflag.h"
+#include "cgo/abi_amd64.h"
+
+#define AT_FDCWD -100
+
+#define SYS_read		0
+#define SYS_write		1
+#define SYS_close		3
+#define SYS_mmap		9
+#define SYS_munmap		11
+#define SYS_brk 		12
+#define SYS_rt_sigaction	13
+#define SYS_rt_sigprocmask	14
+#define SYS_rt_sigreturn	15
+#define SYS_sched_yield 	24
+#define SYS_mincore		27
+#define SYS_madvise		28
+#define SYS_nanosleep		35
+#define SYS_setittimer		38
+#define SYS_getpid		39
+#define SYS_socket		41
+#define SYS_connect		42
+#define SYS_clone		56
+#define SYS_exit		60
+#define SYS_kill		62
+#define SYS_fcntl		72
+#define SYS_sigaltstack 	131
+#define SYS_arch_prctl		158
+#define SYS_gettid		186
+#define SYS_futex		202
+#define SYS_sched_getaffinity	204
+#define SYS_epoll_create	213
+#define SYS_timer_create	222
+#define SYS_timer_settime	223
+#define SYS_timer_delete	226
+#define SYS_clock_gettime	228
+#define SYS_exit_group		231
+#define SYS_epoll_ctl		233
+#define SYS_tgkill		234
+#define SYS_openat		257
+#define SYS_faccessat		269
+#define SYS_epoll_pwait		281
+#define SYS_epoll_create1	291
+#define SYS_pipe2		293
+
+TEXT runtime·exit(SB),NOSPLIT,$0-4
+	MOVL	code+0(FP), DI
+	MOVL	$SYS_exit_group, AX
+	SYSCALL
+	RET
+
+// func exitThread(wait *uint32)
+TEXT runtime·exitThread(SB),NOSPLIT,$0-8
+	MOVQ	wait+0(FP), AX
+	// We're done using the stack.
+	MOVL	$0, (AX)
+	MOVL	$0, DI	// exit code
+	MOVL	$SYS_exit, AX
+	SYSCALL
+	// We may not even have a stack any more.
+	INT	$3
+	JMP	0(PC)
+
+TEXT runtime·open(SB),NOSPLIT,$0-20
+	// This uses openat instead of open, because Android O blocks open.
+	MOVL	$AT_FDCWD, DI // AT_FDCWD, so this acts like open
+	MOVQ	name+0(FP), SI
+	MOVL	mode+8(FP), DX
+	MOVL	perm+12(FP), R10
+	MOVL	$SYS_openat, AX
+	SYSCALL
+	CMPQ	AX, $0xfffffffffffff001
+	JLS	2(PC)
+	MOVL	$-1, AX
+	MOVL	AX, ret+16(FP)
+	RET
+
+TEXT runtime·closefd(SB),NOSPLIT,$0-12
+	MOVL	fd+0(FP), DI
+	MOVL	$SYS_close, AX
+	SYSCALL
+	CMPQ	AX, $0xfffffffffffff001
+	JLS	2(PC)
+	MOVL	$-1, AX
+	MOVL	AX, ret+8(FP)
+	RET
+
+TEXT runtime·write1(SB),NOSPLIT,$0-28
+	MOVQ	fd+0(FP), DI
+	MOVQ	p+8(FP), SI
+	MOVL	n+16(FP), DX
+	MOVL	$SYS_write, AX
+	SYSCALL
+	MOVL	AX, ret+24(FP)
+	RET
+
+TEXT runtime·read(SB),NOSPLIT,$0-28
+	MOVL	fd+0(FP), DI
+	MOVQ	p+8(FP), SI
+	MOVL	n+16(FP), DX
+	MOVL	$SYS_read, AX
+	SYSCALL
+	MOVL	AX, ret+24(FP)
+	RET
+
+// func pipe2(flags int32) (r, w int32, errno int32)
+TEXT runtime·pipe2(SB),NOSPLIT,$0-20
+	LEAQ	r+8(FP), DI
+	MOVL	flags+0(FP), SI
+	MOVL	$SYS_pipe2, AX
+	SYSCALL
+	MOVL	AX, errno+16(FP)
+	RET
+
+TEXT runtime·usleep(SB),NOSPLIT,$16
+	MOVL	$0, DX
+	MOVL	usec+0(FP), AX
+	MOVL	$1000000, CX
+	DIVL	CX
+	MOVQ	AX, 0(SP)
+	MOVL	$1000, AX	// usec to nsec
+	MULL	DX
+	MOVQ	AX, 8(SP)
+
+	// nanosleep(&ts, 0)
+	MOVQ	SP, DI
+	MOVL	$0, SI
+	MOVL	$SYS_nanosleep, AX
+	SYSCALL
+	RET
+
+TEXT runtime·gettid(SB),NOSPLIT,$0-4
+	MOVL	$SYS_gettid, AX
+	SYSCALL
+	MOVL	AX, ret+0(FP)
+	RET
+
+TEXT runtime·raise(SB),NOSPLIT,$0
+	MOVL	$SYS_getpid, AX
+	SYSCALL
+	MOVL	AX, R12
+	MOVL	$SYS_gettid, AX
+	SYSCALL
+	MOVL	AX, SI	// arg 2 tid
+	MOVL	R12, DI	// arg 1 pid
+	MOVL	sig+0(FP), DX	// arg 3
+	MOVL	$SYS_tgkill, AX
+	SYSCALL
+	RET
+
+TEXT runtime·raiseproc(SB),NOSPLIT,$0
+	MOVL	$SYS_getpid, AX
+	SYSCALL
+	MOVL	AX, DI	// arg 1 pid
+	MOVL	sig+0(FP), SI	// arg 2
+	MOVL	$SYS_kill, AX
+	SYSCALL
+	RET
+
+TEXT ·getpid(SB),NOSPLIT,$0-8
+	MOVL	$SYS_getpid, AX
+	SYSCALL
+	MOVQ	AX, ret+0(FP)
+	RET
+
+TEXT ·tgkill(SB),NOSPLIT,$0
+	MOVQ	tgid+0(FP), DI
+	MOVQ	tid+8(FP), SI
+	MOVQ	sig+16(FP), DX
+	MOVL	$SYS_tgkill, AX
+	SYSCALL
+	RET
+
+TEXT runtime·setitimer(SB),NOSPLIT,$0-24
+	MOVL	mode+0(FP), DI
+	MOVQ	new+8(FP), SI
+	MOVQ	old+16(FP), DX
+	MOVL	$SYS_setittimer, AX
+	SYSCALL
+	RET
+
+TEXT runtime·timer_create(SB),NOSPLIT,$0-28
+	MOVL	clockid+0(FP), DI
+	MOVQ	sevp+8(FP), SI
+	MOVQ	timerid+16(FP), DX
+	MOVL	$SYS_timer_create, AX
+	SYSCALL
+	MOVL	AX, ret+24(FP)
+	RET
+
+TEXT runtime·timer_settime(SB),NOSPLIT,$0-28
+	MOVL	timerid+0(FP), DI
+	MOVL	flags+4(FP), SI
+	MOVQ	new+8(FP), DX
+	MOVQ	old+16(FP), R10
+	MOVL	$SYS_timer_settime, AX
+	SYSCALL
+	MOVL	AX, ret+24(FP)
+	RET
+
+TEXT runtime·timer_delete(SB),NOSPLIT,$0-12
+	MOVL	timerid+0(FP), DI
+	MOVL	$SYS_timer_delete, AX
+	SYSCALL
+	MOVL	AX, ret+8(FP)
+	RET
+
+TEXT runtime·mincore(SB),NOSPLIT,$0-28
+	MOVQ	addr+0(FP), DI
+	MOVQ	n+8(FP), SI
+	MOVQ	dst+16(FP), DX
+	MOVL	$SYS_mincore, AX
+	SYSCALL
+	MOVL	AX, ret+24(FP)
+	RET
+
+// func nanotime1() int64
+TEXT runtime·nanotime1(SB),NOSPLIT,$16-8
+	// We don't know how much stack space the VDSO code will need,
+	// so switch to g0.
+	// In particular, a kernel configured with CONFIG_OPTIMIZE_INLINING=n
+	// and hardening can use a full page of stack space in gettime_sym
+	// due to stack probes inserted to avoid stack/heap collisions.
+	// See issue #20427.
+
+	MOVQ	SP, R12	// Save old SP; R12 unchanged by C code.
+
+	MOVQ	g_m(R14), BX // BX unchanged by C code.
+
+	// Set vdsoPC and vdsoSP for SIGPROF traceback.
+	// Save the old values on stack and restore them on exit,
+	// so this function is reentrant.
+	MOVQ	m_vdsoPC(BX), CX
+	MOVQ	m_vdsoSP(BX), DX
+	MOVQ	CX, 0(SP)
+	MOVQ	DX, 8(SP)
+
+	LEAQ	ret+0(FP), DX
+	MOVQ	-8(DX), CX
+	MOVQ	CX, m_vdsoPC(BX)
+	MOVQ	DX, m_vdsoSP(BX)
+
+	CMPQ	R14, m_curg(BX)	// Only switch if on curg.
+	JNE	noswitch
+
+	MOVQ	m_g0(BX), DX
+	MOVQ	(g_sched+gobuf_sp)(DX), SP	// Set SP to g0 stack
+
+noswitch:
+	SUBQ	$16, SP		// Space for results
+	ANDQ	$~15, SP	// Align for C code
+
+	MOVL	$1, DI // CLOCK_MONOTONIC
+	LEAQ	0(SP), SI
+	MOVQ	runtime·vdsoClockgettimeSym(SB), AX
+	CMPQ	AX, $0
+	JEQ	fallback
+	CALL	AX
+ret:
+	MOVQ	0(SP), AX	// sec
+	MOVQ	8(SP), DX	// nsec
+	MOVQ	R12, SP		// Restore real SP
+	// Restore vdsoPC, vdsoSP
+	// We don't worry about being signaled between the two stores.
+	// If we are not in a signal handler, we'll restore vdsoSP to 0,
+	// and no one will care about vdsoPC. If we are in a signal handler,
+	// we cannot receive another signal.
+	MOVQ	8(SP), CX
+	MOVQ	CX, m_vdsoSP(BX)
+	MOVQ	0(SP), CX
+	MOVQ	CX, m_vdsoPC(BX)
+	// sec is in AX, nsec in DX
+	// return nsec in AX
+	IMULQ	$1000000000, AX
+	ADDQ	DX, AX
+	MOVQ	AX, ret+0(FP)
+	RET
+fallback:
+	MOVQ	$SYS_clock_gettime, AX
+	SYSCALL
+	JMP	ret
+
+TEXT runtime·rtsigprocmask(SB),NOSPLIT,$0-28
+	MOVL	how+0(FP), DI
+	MOVQ	new+8(FP), SI
+	MOVQ	old+16(FP), DX
+	MOVL	size+24(FP), R10
+	MOVL	$SYS_rt_sigprocmask, AX
+	SYSCALL
+	CMPQ	AX, $0xfffffffffffff001
+	JLS	2(PC)
+	MOVL	$0xf1, 0xf1  // crash
+	RET
+
+TEXT runtime·rt_sigaction(SB),NOSPLIT,$0-36
+	MOVQ	sig+0(FP), DI
+	MOVQ	new+8(FP), SI
+	MOVQ	old+16(FP), DX
+	MOVQ	size+24(FP), R10
+	MOVL	$SYS_rt_sigaction, AX
+	SYSCALL
+	MOVL	AX, ret+32(FP)
+	RET
+
+// Call the function stored in _cgo_sigaction using the GCC calling convention.
+TEXT runtime·callCgoSigaction(SB),NOSPLIT,$16
+	MOVQ	sig+0(FP), DI
+	MOVQ	new+8(FP), SI
+	MOVQ	old+16(FP), DX
+	MOVQ	_cgo_sigaction(SB), AX
+	MOVQ	SP, BX	// callee-saved
+	ANDQ	$~15, SP	// alignment as per amd64 psABI
+	CALL	AX
+	MOVQ	BX, SP
+	MOVL	AX, ret+24(FP)
+	RET
+
+TEXT runtime·sigfwd(SB),NOSPLIT,$0-32
+	MOVQ	fn+0(FP),    AX
+	MOVL	sig+8(FP),   DI
+	MOVQ	info+16(FP), SI
+	MOVQ	ctx+24(FP),  DX
+	PUSHQ	BP
+	MOVQ	SP, BP
+	ANDQ	$~15, SP     // alignment for x86_64 ABI
+	CALL	AX
+	MOVQ	BP, SP
+	POPQ	BP
+	RET
+
+// Called using C ABI.
+TEXT runtime·sigtramp(SB),NOSPLIT|TOPFRAME,$0
+	// Transition from C ABI to Go ABI.
+	PUSH_REGS_HOST_TO_ABI0()
+
+	// Set up ABIInternal environment: g in R14, cleared X15.
+	get_tls(R12)
+	MOVQ	g(R12), R14
+	PXOR	X15, X15
+
+	// Reserve space for spill slots.
+	NOP	SP		// disable vet stack checking
+	ADJSP   $24
+
+	// Call into the Go signal handler
+	MOVQ	DI, AX	// sig
+	MOVQ	SI, BX	// info
+	MOVQ	DX, CX	// ctx
+	CALL	·sigtrampgo<ABIInternal>(SB)
+
+	ADJSP	$-24
+
+        POP_REGS_HOST_TO_ABI0()
+	RET
+
+// Called using C ABI.
+TEXT runtime·sigprofNonGoWrapper<>(SB),NOSPLIT,$0
+	// Transition from C ABI to Go ABI.
+	PUSH_REGS_HOST_TO_ABI0()
+
+	// Set up ABIInternal environment: g in R14, cleared X15.
+	get_tls(R12)
+	MOVQ	g(R12), R14
+	PXOR	X15, X15
+
+	// Reserve space for spill slots.
+	NOP	SP		// disable vet stack checking
+	ADJSP   $24
+
+	// Call into the Go signal handler
+	MOVQ	DI, AX	// sig
+	MOVQ	SI, BX	// info
+	MOVQ	DX, CX	// ctx
+	CALL	·sigprofNonGo<ABIInternal>(SB)
+
+	ADJSP	$-24
+
+	POP_REGS_HOST_TO_ABI0()
+	RET
+
+// Used instead of sigtramp in programs that use cgo.
+// Arguments from kernel are in DI, SI, DX.
+TEXT runtime·cgoSigtramp(SB),NOSPLIT,$0
+	// If no traceback function, do usual sigtramp.
+	MOVQ	runtime·cgoTraceback(SB), AX
+	TESTQ	AX, AX
+	JZ	sigtramp
+
+	// If no traceback support function, which means that
+	// runtime/cgo was not linked in, do usual sigtramp.
+	MOVQ	_cgo_callers(SB), AX
+	TESTQ	AX, AX
+	JZ	sigtramp
+
+	// Figure out if we are currently in a cgo call.
+	// If not, just do usual sigtramp.
+	get_tls(CX)
+	MOVQ	g(CX),AX
+	TESTQ	AX, AX
+	JZ	sigtrampnog     // g == nil
+	MOVQ	g_m(AX), AX
+	TESTQ	AX, AX
+	JZ	sigtramp        // g.m == nil
+	MOVL	m_ncgo(AX), CX
+	TESTL	CX, CX
+	JZ	sigtramp        // g.m.ncgo == 0
+	MOVQ	m_curg(AX), CX
+	TESTQ	CX, CX
+	JZ	sigtramp        // g.m.curg == nil
+	MOVQ	g_syscallsp(CX), CX
+	TESTQ	CX, CX
+	JZ	sigtramp        // g.m.curg.syscallsp == 0
+	MOVQ	m_cgoCallers(AX), R8
+	TESTQ	R8, R8
+	JZ	sigtramp        // g.m.cgoCallers == nil
+	MOVL	m_cgoCallersUse(AX), CX
+	TESTL	CX, CX
+	JNZ	sigtramp	// g.m.cgoCallersUse != 0
+
+	// Jump to a function in runtime/cgo.
+	// That function, written in C, will call the user's traceback
+	// function with proper unwind info, and will then call back here.
+	// The first three arguments, and the fifth, are already in registers.
+	// Set the two remaining arguments now.
+	MOVQ	runtime·cgoTraceback(SB), CX
+	MOVQ	$runtime·sigtramp(SB), R9
+	MOVQ	_cgo_callers(SB), AX
+	JMP	AX
+
+sigtramp:
+	JMP	runtime·sigtramp(SB)
+
+sigtrampnog:
+	// Signal arrived on a non-Go thread. If this is SIGPROF, get a
+	// stack trace.
+	CMPL	DI, $27 // 27 == SIGPROF
+	JNZ	sigtramp
+
+	// Lock sigprofCallersUse.
+	MOVL	$0, AX
+	MOVL	$1, CX
+	MOVQ	$runtime·sigprofCallersUse(SB), R11
+	LOCK
+	CMPXCHGL	CX, 0(R11)
+	JNZ	sigtramp  // Skip stack trace if already locked.
+
+	// Jump to the traceback function in runtime/cgo.
+	// It will call back to sigprofNonGo, via sigprofNonGoWrapper, to convert
+	// the arguments to the Go calling convention.
+	// First three arguments to traceback function are in registers already.
+	MOVQ	runtime·cgoTraceback(SB), CX
+	MOVQ	$runtime·sigprofCallers(SB), R8
+	MOVQ	$runtime·sigprofNonGoWrapper<>(SB), R9
+	MOVQ	_cgo_callers(SB), AX
+	JMP	AX
+
+// For cgo unwinding to work, this function must look precisely like
+// the one in glibc.  The glibc source code is:
+// https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/unix/sysv/linux/x86_64/sigaction.c
+// The code that cares about the precise instructions used is:
+// https://gcc.gnu.org/viewcvs/gcc/trunk/libgcc/config/i386/linux-unwind.h?revision=219188&view=markup
+TEXT runtime·sigreturn(SB),NOSPLIT,$0
+	MOVQ	$SYS_rt_sigreturn, AX
+	SYSCALL
+	INT $3	// not reached
+
+TEXT runtime·sysMmap(SB),NOSPLIT,$0
+	MOVQ	addr+0(FP), DI
+	MOVQ	n+8(FP), SI
+	MOVL	prot+16(FP), DX
+	MOVL	flags+20(FP), R10
+	MOVL	fd+24(FP), R8
+	MOVL	off+28(FP), R9
+
+	MOVL	$SYS_mmap, AX
+	SYSCALL
+	CMPQ	AX, $0xfffffffffffff001
+	JLS	ok
+	NOTQ	AX
+	INCQ	AX
+	MOVQ	$0, p+32(FP)
+	MOVQ	AX, err+40(FP)
+	RET
+ok:
+	MOVQ	AX, p+32(FP)
+	MOVQ	$0, err+40(FP)
+	RET
+
+// Call the function stored in _cgo_mmap using the GCC calling convention.
+// This must be called on the system stack.
+TEXT runtime·callCgoMmap(SB),NOSPLIT,$16
+	MOVQ	addr+0(FP), DI
+	MOVQ	n+8(FP), SI
+	MOVL	prot+16(FP), DX
+	MOVL	flags+20(FP), CX
+	MOVL	fd+24(FP), R8
+	MOVL	off+28(FP), R9
+	MOVQ	_cgo_mmap(SB), AX
+	MOVQ	SP, BX
+	ANDQ	$~15, SP	// alignment as per amd64 psABI
+	MOVQ	BX, 0(SP)
+	CALL	AX
+	MOVQ	0(SP), SP
+	MOVQ	AX, ret+32(FP)
+	RET
+
+TEXT runtime·sysMunmap(SB),NOSPLIT,$0
+	MOVQ	addr+0(FP), DI
+	MOVQ	n+8(FP), SI
+	MOVQ	$SYS_munmap, AX
+	SYSCALL
+	CMPQ	AX, $0xfffffffffffff001
+	JLS	2(PC)
+	MOVL	$0xf1, 0xf1  // crash
+	RET
+
+// Call the function stored in _cgo_munmap using the GCC calling convention.
+// This must be called on the system stack.
+TEXT runtime·callCgoMunmap(SB),NOSPLIT,$16-16
+	MOVQ	addr+0(FP), DI
+	MOVQ	n+8(FP), SI
+	MOVQ	_cgo_munmap(SB), AX
+	MOVQ	SP, BX
+	ANDQ	$~15, SP	// alignment as per amd64 psABI
+	MOVQ	BX, 0(SP)
+	CALL	AX
+	MOVQ	0(SP), SP
+	RET
+
+TEXT runtime·madvise(SB),NOSPLIT,$0
+	MOVQ	addr+0(FP), DI
+	MOVQ	n+8(FP), SI
+	MOVL	flags+16(FP), DX
+	MOVQ	$SYS_madvise, AX
+	SYSCALL
+	MOVL	AX, ret+24(FP)
+	RET
+
+// int64 futex(int32 *uaddr, int32 op, int32 val,
+//	struct timespec *timeout, int32 *uaddr2, int32 val2);
+TEXT runtime·futex(SB),NOSPLIT,$0
+	MOVQ	addr+0(FP), DI
+	MOVL	op+8(FP), SI
+	MOVL	val+12(FP), DX
+	MOVQ	ts+16(FP), R10
+	MOVQ	addr2+24(FP), R8
+	MOVL	val3+32(FP), R9
+	MOVL	$SYS_futex, AX
+	SYSCALL
+	MOVL	AX, ret+40(FP)
+	RET
+
+// int32 clone(int32 flags, void *stk, M *mp, G *gp, void (*fn)(void));
+TEXT runtime·clone(SB),NOSPLIT,$0
+	MOVL	flags+0(FP), DI
+	MOVQ	stk+8(FP), SI
+	MOVQ	$0, DX
+	MOVQ	$0, R10
+	MOVQ    $0, R8
+	// Copy mp, gp, fn off parent stack for use by child.
+	// Careful: Linux system call clobbers CX and R11.
+	MOVQ	mp+16(FP), R13
+	MOVQ	gp+24(FP), R9
+	MOVQ	fn+32(FP), R12
+	CMPQ	R13, $0    // m
+	JEQ	nog1
+	CMPQ	R9, $0    // g
+	JEQ	nog1
+	LEAQ	m_tls(R13), R8
+#ifdef GOOS_android
+	// Android stores the TLS offset in runtime·tls_g.
+	SUBQ	runtime·tls_g(SB), R8
+#else
+	ADDQ	$8, R8	// ELF wants to use -8(FS)
+#endif
+	ORQ 	$0x00080000, DI //add flag CLONE_SETTLS(0x00080000) to call clone
+nog1:
+	MOVL	$SYS_clone, AX
+	SYSCALL
+
+	// In parent, return.
+	CMPQ	AX, $0
+	JEQ	3(PC)
+	MOVL	AX, ret+40(FP)
+	RET
+
+	// In child, on new stack.
+	MOVQ	SI, SP
+
+	// If g or m are nil, skip Go-related setup.
+	CMPQ	R13, $0    // m
+	JEQ	nog2
+	CMPQ	R9, $0    // g
+	JEQ	nog2
+
+	// Initialize m->procid to Linux tid
+	MOVL	$SYS_gettid, AX
+	SYSCALL
+	MOVQ	AX, m_procid(R13)
+
+	// In child, set up new stack
+	get_tls(CX)
+	MOVQ	R13, g_m(R9)
+	MOVQ	R9, g(CX)
+	MOVQ	R9, R14 // set g register
+	CALL	runtime·stackcheck(SB)
+
+nog2:
+	// Call fn. This is the PC of an ABI0 function.
+	CALL	R12
+
+	// It shouldn't return. If it does, exit that thread.
+	MOVL	$111, DI
+	MOVL	$SYS_exit, AX
+	SYSCALL
+	JMP	-3(PC)	// keep exiting
+
+TEXT runtime·sigaltstack(SB),NOSPLIT,$-8
+	MOVQ	new+0(FP), DI
+	MOVQ	old+8(FP), SI
+	MOVQ	$SYS_sigaltstack, AX
+	SYSCALL
+	CMPQ	AX, $0xfffffffffffff001
+	JLS	2(PC)
+	MOVL	$0xf1, 0xf1  // crash
+	RET
+
+// set tls base to DI
+TEXT runtime·settls(SB),NOSPLIT,$32
+#ifdef GOOS_android
+	// Android stores the TLS offset in runtime·tls_g.
+	SUBQ	runtime·tls_g(SB), DI
+#else
+	ADDQ	$8, DI	// ELF wants to use -8(FS)
+#endif
+	MOVQ	DI, SI
+	MOVQ	$0x1002, DI	// ARCH_SET_FS
+	MOVQ	$SYS_arch_prctl, AX
+	SYSCALL
+	CMPQ	AX, $0xfffffffffffff001
+	JLS	2(PC)
+	MOVL	$0xf1, 0xf1  // crash
+	RET
+
+TEXT runtime·osyield(SB),NOSPLIT,$0
+	MOVL	$SYS_sched_yield, AX
+	SYSCALL
+	RET
+
+TEXT runtime·sched_getaffinity(SB),NOSPLIT,$0
+	MOVQ	pid+0(FP), DI
+	MOVQ	len+8(FP), SI
+	MOVQ	buf+16(FP), DX
+	MOVL	$SYS_sched_getaffinity, AX
+	SYSCALL
+	MOVL	AX, ret+24(FP)
+	RET
+
+// int32 runtime·epollcreate(int32 size);
+TEXT runtime·epollcreate(SB),NOSPLIT,$0
+	MOVL    size+0(FP), DI
+	MOVL    $SYS_epoll_create, AX
+	SYSCALL
+	MOVL	AX, ret+8(FP)
+	RET
+
+// int32 runtime·epollcreate1(int32 flags);
+TEXT runtime·epollcreate1(SB),NOSPLIT,$0
+	MOVL	flags+0(FP), DI
+	MOVL	$SYS_epoll_create1, AX
+	SYSCALL
+	MOVL	AX, ret+8(FP)
+	RET
+
+// func epollctl(epfd, op, fd int32, ev *epollEvent) int
+TEXT runtime·epollctl(SB),NOSPLIT,$0
+	MOVL	epfd+0(FP), DI
+	MOVL	op+4(FP), SI
+	MOVL	fd+8(FP), DX
+	MOVQ	ev+16(FP), R10
+	MOVL	$SYS_epoll_ctl, AX
+	SYSCALL
+	MOVL	AX, ret+24(FP)
+	RET
+
+// int32 runtime·epollwait(int32 epfd, EpollEvent *ev, int32 nev, int32 timeout);
+TEXT runtime·epollwait(SB),NOSPLIT,$0
+	// This uses pwait instead of wait, because Android O blocks wait.
+	MOVL	epfd+0(FP), DI
+	MOVQ	ev+8(FP), SI
+	MOVL	nev+16(FP), DX
+	MOVL	timeout+20(FP), R10
+	MOVQ	$0, R8
+	MOVL	$SYS_epoll_pwait, AX
+	SYSCALL
+	MOVL	AX, ret+24(FP)
+	RET
+
+// void runtime·closeonexec(int32 fd);
+TEXT runtime·closeonexec(SB),NOSPLIT,$0
+	MOVL    fd+0(FP), DI  // fd
+	MOVQ    $2, SI  // F_SETFD
+	MOVQ    $1, DX  // FD_CLOEXEC
+	MOVL	$SYS_fcntl, AX
+	SYSCALL
+	RET
+
+// int access(const char *name, int mode)
+TEXT runtime·access(SB),NOSPLIT,$0
+	// This uses faccessat instead of access, because Android O blocks access.
+	MOVL	$AT_FDCWD, DI // AT_FDCWD, so this acts like access
+	MOVQ	name+0(FP), SI
+	MOVL	mode+8(FP), DX
+	MOVL	$0, R10
+	MOVL	$SYS_faccessat, AX
+	SYSCALL
+	MOVL	AX, ret+16(FP)
+	RET
+
+// int connect(int fd, const struct sockaddr *addr, socklen_t addrlen)
+TEXT runtime·connect(SB),NOSPLIT,$0-28
+	MOVL	fd+0(FP), DI
+	MOVQ	addr+8(FP), SI
+	MOVL	len+16(FP), DX
+	MOVL	$SYS_connect, AX
+	SYSCALL
+	MOVL	AX, ret+24(FP)
+	RET
+
+// int socket(int domain, int type, int protocol)
+TEXT runtime·socket(SB),NOSPLIT,$0-20
+	MOVL	domain+0(FP), DI
+	MOVL	typ+4(FP), SI
+	MOVL	prot+8(FP), DX
+	MOVL	$SYS_socket, AX
+	SYSCALL
+	MOVL	AX, ret+16(FP)
+	RET
+
+// func sbrk0() uintptr
+TEXT runtime·sbrk0(SB),NOSPLIT,$0-8
+	// Implemented as brk(NULL).
+	MOVQ	$0, DI
+	MOVL	$SYS_brk, AX
+	SYSCALL
+	MOVQ	AX, ret+0(FP)
+	RET
diff --git a/contrib/go/_std_1.18/src/runtime/sys_nonppc64x.go b/contrib/go/_std_1.19/src/runtime/sys_nonppc64x.go
index 653f1c999f..653f1c999f 100644
--- a/contrib/go/_std_1.18/src/runtime/sys_nonppc64x.go
+++ b/contrib/go/_std_1.19/src/runtime/sys_nonppc64x.go
diff --git a/contrib/go/_std_1.18/src/runtime/sys_x86.go b/contrib/go/_std_1.19/src/runtime/sys_x86.go
index 9fb36c2a66..9fb36c2a66 100644
--- a/contrib/go/_std_1.18/src/runtime/sys_x86.go
+++ b/contrib/go/_std_1.19/src/runtime/sys_x86.go
diff --git a/contrib/go/_std_1.18/src/runtime/textflag.h b/contrib/go/_std_1.19/src/runtime/textflag.h
index 214075e360..214075e360 100644
--- a/contrib/go/_std_1.18/src/runtime/textflag.h
+++ b/contrib/go/_std_1.19/src/runtime/textflag.h
diff --git a/contrib/go/_std_1.19/src/runtime/time.go b/contrib/go/_std_1.19/src/runtime/time.go
new file mode 100644
index 0000000000..80b0bfb72c
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/time.go
@@ -0,0 +1,1142 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Time-related runtime and pieces of package time.
+
+package runtime
+
+import (
+	"internal/abi"
+	"runtime/internal/atomic"
+	"runtime/internal/sys"
+	"unsafe"
+)
+
+// Package time knows the layout of this structure.
+// If this struct changes, adjust ../time/sleep.go:/runtimeTimer.
+type timer struct {
+	// If this timer is on a heap, which P's heap it is on.
+	// puintptr rather than *p to match uintptr in the versions
+	// of this struct defined in other packages.
+	pp puintptr
+
+	// Timer wakes up at when, and then at when+period, ... (period > 0 only)
+	// each time calling f(arg, now) in the timer goroutine, so f must be
+	// a well-behaved function and not block.
+	//
+	// when must be positive on an active timer.
+	when   int64
+	period int64
+	f      func(any, uintptr)
+	arg    any
+	seq    uintptr
+
+	// What to set the when field to in timerModifiedXX status.
+	nextwhen int64
+
+	// The status field holds one of the values below.
+	status uint32
+}
+
+// Code outside this file has to be careful in using a timer value.
+//
+// The pp, status, and nextwhen fields may only be used by code in this file.
+//
+// Code that creates a new timer value can set the when, period, f,
+// arg, and seq fields.
+// A new timer value may be passed to addtimer (called by time.startTimer).
+// After doing that no fields may be touched.
+//
+// An active timer (one that has been passed to addtimer) may be
+// passed to deltimer (time.stopTimer), after which it is no longer an
+// active timer. It is an inactive timer.
+// In an inactive timer the period, f, arg, and seq fields may be modified,
+// but not the when field.
+// It's OK to just drop an inactive timer and let the GC collect it.
+// It's not OK to pass an inactive timer to addtimer.
+// Only newly allocated timer values may be passed to addtimer.
+//
+// An active timer may be passed to modtimer. No fields may be touched.
+// It remains an active timer.
+//
+// An inactive timer may be passed to resettimer to turn into an
+// active timer with an updated when field.
+// It's OK to pass a newly allocated timer value to resettimer.
+//
+// Timer operations are addtimer, deltimer, modtimer, resettimer,
+// cleantimers, adjusttimers, and runtimer.
+//
+// We don't permit calling addtimer/deltimer/modtimer/resettimer simultaneously,
+// but adjusttimers and runtimer can be called at the same time as any of those.
+//
+// Active timers live in heaps attached to P, in the timers field.
+// Inactive timers live there too temporarily, until they are removed.
+//
+// addtimer:
+//   timerNoStatus   -> timerWaiting
+//   anything else   -> panic: invalid value
+// deltimer:
+//   timerWaiting         -> timerModifying -> timerDeleted
+//   timerModifiedEarlier -> timerModifying -> timerDeleted
+//   timerModifiedLater   -> timerModifying -> timerDeleted
+//   timerNoStatus        -> do nothing
+//   timerDeleted         -> do nothing
+//   timerRemoving        -> do nothing
+//   timerRemoved         -> do nothing
+//   timerRunning         -> wait until status changes
+//   timerMoving          -> wait until status changes
+//   timerModifying       -> wait until status changes
+// modtimer:
+//   timerWaiting    -> timerModifying -> timerModifiedXX
+//   timerModifiedXX -> timerModifying -> timerModifiedYY
+//   timerNoStatus   -> timerModifying -> timerWaiting
+//   timerRemoved    -> timerModifying -> timerWaiting
+//   timerDeleted    -> timerModifying -> timerModifiedXX
+//   timerRunning    -> wait until status changes
+//   timerMoving     -> wait until status changes
+//   timerRemoving   -> wait until status changes
+//   timerModifying  -> wait until status changes
+// cleantimers (looks in P's timer heap):
+//   timerDeleted    -> timerRemoving -> timerRemoved
+//   timerModifiedXX -> timerMoving -> timerWaiting
+// adjusttimers (looks in P's timer heap):
+//   timerDeleted    -> timerRemoving -> timerRemoved
+//   timerModifiedXX -> timerMoving -> timerWaiting
+// runtimer (looks in P's timer heap):
+//   timerNoStatus   -> panic: uninitialized timer
+//   timerWaiting    -> timerWaiting or
+//   timerWaiting    -> timerRunning -> timerNoStatus or
+//   timerWaiting    -> timerRunning -> timerWaiting
+//   timerModifying  -> wait until status changes
+//   timerModifiedXX -> timerMoving -> timerWaiting
+//   timerDeleted    -> timerRemoving -> timerRemoved
+//   timerRunning    -> panic: concurrent runtimer calls
+//   timerRemoved    -> panic: inconsistent timer heap
+//   timerRemoving   -> panic: inconsistent timer heap
+//   timerMoving     -> panic: inconsistent timer heap
+
+// Values for the timer status field.
+const (
+	// Timer has no status set yet.
+	timerNoStatus = iota
+
+	// Waiting for timer to fire.
+	// The timer is in some P's heap.
+	timerWaiting
+
+	// Running the timer function.
+	// A timer will only have this status briefly.
+	timerRunning
+
+	// The timer is deleted and should be removed.
+	// It should not be run, but it is still in some P's heap.
+	timerDeleted
+
+	// The timer is being removed.
+	// The timer will only have this status briefly.
+	timerRemoving
+
+	// The timer has been stopped.
+	// It is not in any P's heap.
+	timerRemoved
+
+	// The timer is being modified.
+	// The timer will only have this status briefly.
+	timerModifying
+
+	// The timer has been modified to an earlier time.
+	// The new when value is in the nextwhen field.
+	// The timer is in some P's heap, possibly in the wrong place.
+	timerModifiedEarlier
+
+	// The timer has been modified to the same or a later time.
+	// The new when value is in the nextwhen field.
+	// The timer is in some P's heap, possibly in the wrong place.
+	timerModifiedLater
+
+	// The timer has been modified and is being moved.
+	// The timer will only have this status briefly.
+	timerMoving
+)
+
+// maxWhen is the maximum value for timer's when field.
+const maxWhen = 1<<63 - 1
+
+// verifyTimers can be set to true to add debugging checks that the
+// timer heaps are valid.
+const verifyTimers = false
+
+// Package time APIs.
+// Godoc uses the comments in package time, not these.
+
+// time.now is implemented in assembly.
+
+// timeSleep puts the current goroutine to sleep for at least ns nanoseconds.
+//
+//go:linkname timeSleep time.Sleep
+func timeSleep(ns int64) {
+	if ns <= 0 {
+		return
+	}
+
+	gp := getg()
+	t := gp.timer
+	if t == nil {
+		t = new(timer)
+		gp.timer = t
+	}
+	t.f = goroutineReady
+	t.arg = gp
+	t.nextwhen = nanotime() + ns
+	if t.nextwhen < 0 { // check for overflow.
+		t.nextwhen = maxWhen
+	}
+	gopark(resetForSleep, unsafe.Pointer(t), waitReasonSleep, traceEvGoSleep, 1)
+}
+
+// resetForSleep is called after the goroutine is parked for timeSleep.
+// We can't call resettimer in timeSleep itself because if this is a short
+// sleep and there are many goroutines then the P can wind up running the
+// timer function, goroutineReady, before the goroutine has been parked.
+func resetForSleep(gp *g, ut unsafe.Pointer) bool {
+	t := (*timer)(ut)
+	resettimer(t, t.nextwhen)
+	return true
+}
+
+// startTimer adds t to the timer heap.
+//
+//go:linkname startTimer time.startTimer
+func startTimer(t *timer) {
+	if raceenabled {
+		racerelease(unsafe.Pointer(t))
+	}
+	addtimer(t)
+}
+
+// stopTimer stops a timer.
+// It reports whether t was stopped before being run.
+//
+//go:linkname stopTimer time.stopTimer
+func stopTimer(t *timer) bool {
+	return deltimer(t)
+}
+
+// resetTimer resets an inactive timer, adding it to the heap.
+//
+// Reports whether the timer was modified before it was run.
+//
+//go:linkname resetTimer time.resetTimer
+func resetTimer(t *timer, when int64) bool {
+	if raceenabled {
+		racerelease(unsafe.Pointer(t))
+	}
+	return resettimer(t, when)
+}
+
+// modTimer modifies an existing timer.
+//
+//go:linkname modTimer time.modTimer
+func modTimer(t *timer, when, period int64, f func(any, uintptr), arg any, seq uintptr) {
+	modtimer(t, when, period, f, arg, seq)
+}
+
+// Go runtime.
+
+// Ready the goroutine arg.
+func goroutineReady(arg any, seq uintptr) {
+	goready(arg.(*g), 0)
+}
+
+// addtimer adds a timer to the current P.
+// This should only be called with a newly created timer.
+// That avoids the risk of changing the when field of a timer in some P's heap,
+// which could cause the heap to become unsorted.
+func addtimer(t *timer) {
+	// when must be positive. A negative value will cause runtimer to
+	// overflow during its delta calculation and never expire other runtime
+	// timers. Zero will cause checkTimers to fail to notice the timer.
+	if t.when <= 0 {
+		throw("timer when must be positive")
+	}
+	if t.period < 0 {
+		throw("timer period must be non-negative")
+	}
+	if t.status != timerNoStatus {
+		throw("addtimer called with initialized timer")
+	}
+	t.status = timerWaiting
+
+	when := t.when
+
+	// Disable preemption while using pp to avoid changing another P's heap.
+	mp := acquirem()
+
+	pp := getg().m.p.ptr()
+	lock(&pp.timersLock)
+	cleantimers(pp)
+	doaddtimer(pp, t)
+	unlock(&pp.timersLock)
+
+	wakeNetPoller(when)
+
+	releasem(mp)
+}
+
+// doaddtimer adds t to the current P's heap.
+// The caller must have locked the timers for pp.
+func doaddtimer(pp *p, t *timer) {
+	// Timers rely on the network poller, so make sure the poller
+	// has started.
+	if netpollInited == 0 {
+		netpollGenericInit()
+	}
+
+	if t.pp != 0 {
+		throw("doaddtimer: P already set in timer")
+	}
+	t.pp.set(pp)
+	i := len(pp.timers)
+	pp.timers = append(pp.timers, t)
+	siftupTimer(pp.timers, i)
+	if t == pp.timers[0] {
+		atomic.Store64(&pp.timer0When, uint64(t.when))
+	}
+	atomic.Xadd(&pp.numTimers, 1)
+}
+
+// deltimer deletes the timer t. It may be on some other P, so we can't
+// actually remove it from the timers heap. We can only mark it as deleted.
+// It will be removed in due course by the P whose heap it is on.
+// Reports whether the timer was removed before it was run.
+func deltimer(t *timer) bool {
+	for {
+		switch s := atomic.Load(&t.status); s {
+		case timerWaiting, timerModifiedLater:
+			// Prevent preemption while the timer is in timerModifying.
+			// This could lead to a self-deadlock. See #38070.
+			mp := acquirem()
+			if atomic.Cas(&t.status, s, timerModifying) {
+				// Must fetch t.pp before changing status,
+				// as cleantimers in another goroutine
+				// can clear t.pp of a timerDeleted timer.
+				tpp := t.pp.ptr()
+				if !atomic.Cas(&t.status, timerModifying, timerDeleted) {
+					badTimer()
+				}
+				releasem(mp)
+				atomic.Xadd(&tpp.deletedTimers, 1)
+				// Timer was not yet run.
+				return true
+			} else {
+				releasem(mp)
+			}
+		case timerModifiedEarlier:
+			// Prevent preemption while the timer is in timerModifying.
+			// This could lead to a self-deadlock. See #38070.
+			mp := acquirem()
+			if atomic.Cas(&t.status, s, timerModifying) {
+				// Must fetch t.pp before setting status
+				// to timerDeleted.
+				tpp := t.pp.ptr()
+				if !atomic.Cas(&t.status, timerModifying, timerDeleted) {
+					badTimer()
+				}
+				releasem(mp)
+				atomic.Xadd(&tpp.deletedTimers, 1)
+				// Timer was not yet run.
+				return true
+			} else {
+				releasem(mp)
+			}
+		case timerDeleted, timerRemoving, timerRemoved:
+			// Timer was already run.
+			return false
+		case timerRunning, timerMoving:
+			// The timer is being run or moved, by a different P.
+			// Wait for it to complete.
+			osyield()
+		case timerNoStatus:
+			// Removing timer that was never added or
+			// has already been run. Also see issue 21874.
+			return false
+		case timerModifying:
+			// Simultaneous calls to deltimer and modtimer.
+			// Wait for the other call to complete.
+			osyield()
+		default:
+			badTimer()
+		}
+	}
+}
+
+// dodeltimer removes timer i from the current P's heap.
+// We are locked on the P when this is called.
+// It returns the smallest changed index in pp.timers.
+// The caller must have locked the timers for pp.
+func dodeltimer(pp *p, i int) int {
+	if t := pp.timers[i]; t.pp.ptr() != pp {
+		throw("dodeltimer: wrong P")
+	} else {
+		t.pp = 0
+	}
+	last := len(pp.timers) - 1
+	if i != last {
+		pp.timers[i] = pp.timers[last]
+	}
+	pp.timers[last] = nil
+	pp.timers = pp.timers[:last]
+	smallestChanged := i
+	if i != last {
+		// Moving to i may have moved the last timer to a new parent,
+		// so sift up to preserve the heap guarantee.
+		smallestChanged = siftupTimer(pp.timers, i)
+		siftdownTimer(pp.timers, i)
+	}
+	if i == 0 {
+		updateTimer0When(pp)
+	}
+	n := atomic.Xadd(&pp.numTimers, -1)
+	if n == 0 {
+		// If there are no timers, then clearly none are modified.
+		atomic.Store64(&pp.timerModifiedEarliest, 0)
+	}
+	return smallestChanged
+}
+
+// dodeltimer0 removes timer 0 from the current P's heap.
+// We are locked on the P when this is called.
+// It reports whether it saw no problems due to races.
+// The caller must have locked the timers for pp.
+func dodeltimer0(pp *p) {
+	if t := pp.timers[0]; t.pp.ptr() != pp {
+		throw("dodeltimer0: wrong P")
+	} else {
+		t.pp = 0
+	}
+	last := len(pp.timers) - 1
+	if last > 0 {
+		pp.timers[0] = pp.timers[last]
+	}
+	pp.timers[last] = nil
+	pp.timers = pp.timers[:last]
+	if last > 0 {
+		siftdownTimer(pp.timers, 0)
+	}
+	updateTimer0When(pp)
+	n := atomic.Xadd(&pp.numTimers, -1)
+	if n == 0 {
+		// If there are no timers, then clearly none are modified.
+		atomic.Store64(&pp.timerModifiedEarliest, 0)
+	}
+}
+
+// modtimer modifies an existing timer.
+// This is called by the netpoll code or time.Ticker.Reset or time.Timer.Reset.
+// Reports whether the timer was modified before it was run.
+func modtimer(t *timer, when, period int64, f func(any, uintptr), arg any, seq uintptr) bool {
+	if when <= 0 {
+		throw("timer when must be positive")
+	}
+	if period < 0 {
+		throw("timer period must be non-negative")
+	}
+
+	status := uint32(timerNoStatus)
+	wasRemoved := false
+	var pending bool
+	var mp *m
+loop:
+	for {
+		switch status = atomic.Load(&t.status); status {
+		case timerWaiting, timerModifiedEarlier, timerModifiedLater:
+			// Prevent preemption while the timer is in timerModifying.
+			// This could lead to a self-deadlock. See #38070.
+			mp = acquirem()
+			if atomic.Cas(&t.status, status, timerModifying) {
+				pending = true // timer not yet run
+				break loop
+			}
+			releasem(mp)
+		case timerNoStatus, timerRemoved:
+			// Prevent preemption while the timer is in timerModifying.
+			// This could lead to a self-deadlock. See #38070.
+			mp = acquirem()
+
+			// Timer was already run and t is no longer in a heap.
+			// Act like addtimer.
+			if atomic.Cas(&t.status, status, timerModifying) {
+				wasRemoved = true
+				pending = false // timer already run or stopped
+				break loop
+			}
+			releasem(mp)
+		case timerDeleted:
+			// Prevent preemption while the timer is in timerModifying.
+			// This could lead to a self-deadlock. See #38070.
+			mp = acquirem()
+			if atomic.Cas(&t.status, status, timerModifying) {
+				atomic.Xadd(&t.pp.ptr().deletedTimers, -1)
+				pending = false // timer already stopped
+				break loop
+			}
+			releasem(mp)
+		case timerRunning, timerRemoving, timerMoving:
+			// The timer is being run or moved, by a different P.
+			// Wait for it to complete.
+			osyield()
+		case timerModifying:
+			// Multiple simultaneous calls to modtimer.
+			// Wait for the other call to complete.
+			osyield()
+		default:
+			badTimer()
+		}
+	}
+
+	t.period = period
+	t.f = f
+	t.arg = arg
+	t.seq = seq
+
+	if wasRemoved {
+		t.when = when
+		pp := getg().m.p.ptr()
+		lock(&pp.timersLock)
+		doaddtimer(pp, t)
+		unlock(&pp.timersLock)
+		if !atomic.Cas(&t.status, timerModifying, timerWaiting) {
+			badTimer()
+		}
+		releasem(mp)
+		wakeNetPoller(when)
+	} else {
+		// The timer is in some other P's heap, so we can't change
+		// the when field. If we did, the other P's heap would
+		// be out of order. So we put the new when value in the
+		// nextwhen field, and let the other P set the when field
+		// when it is prepared to resort the heap.
+		t.nextwhen = when
+
+		newStatus := uint32(timerModifiedLater)
+		if when < t.when {
+			newStatus = timerModifiedEarlier
+		}
+
+		tpp := t.pp.ptr()
+
+		if newStatus == timerModifiedEarlier {
+			updateTimerModifiedEarliest(tpp, when)
+		}
+
+		// Set the new status of the timer.
+		if !atomic.Cas(&t.status, timerModifying, newStatus) {
+			badTimer()
+		}
+		releasem(mp)
+
+		// If the new status is earlier, wake up the poller.
+		if newStatus == timerModifiedEarlier {
+			wakeNetPoller(when)
+		}
+	}
+
+	return pending
+}
+
+// resettimer resets the time when a timer should fire.
+// If used for an inactive timer, the timer will become active.
+// This should be called instead of addtimer if the timer value has been,
+// or may have been, used previously.
+// Reports whether the timer was modified before it was run.
+func resettimer(t *timer, when int64) bool {
+	return modtimer(t, when, t.period, t.f, t.arg, t.seq)
+}
+
+// cleantimers cleans up the head of the timer queue. This speeds up
+// programs that create and delete timers; leaving them in the heap
+// slows down addtimer. Reports whether no timer problems were found.
+// The caller must have locked the timers for pp.
+func cleantimers(pp *p) {
+	gp := getg()
+	for {
+		if len(pp.timers) == 0 {
+			return
+		}
+
+		// This loop can theoretically run for a while, and because
+		// it is holding timersLock it cannot be preempted.
+		// If someone is trying to preempt us, just return.
+		// We can clean the timers later.
+		if gp.preemptStop {
+			return
+		}
+
+		t := pp.timers[0]
+		if t.pp.ptr() != pp {
+			throw("cleantimers: bad p")
+		}
+		switch s := atomic.Load(&t.status); s {
+		case timerDeleted:
+			if !atomic.Cas(&t.status, s, timerRemoving) {
+				continue
+			}
+			dodeltimer0(pp)
+			if !atomic.Cas(&t.status, timerRemoving, timerRemoved) {
+				badTimer()
+			}
+			atomic.Xadd(&pp.deletedTimers, -1)
+		case timerModifiedEarlier, timerModifiedLater:
+			if !atomic.Cas(&t.status, s, timerMoving) {
+				continue
+			}
+			// Now we can change the when field.
+			t.when = t.nextwhen
+			// Move t to the right position.
+			dodeltimer0(pp)
+			doaddtimer(pp, t)
+			if !atomic.Cas(&t.status, timerMoving, timerWaiting) {
+				badTimer()
+			}
+		default:
+			// Head of timers does not need adjustment.
+			return
+		}
+	}
+}
+
+// moveTimers moves a slice of timers to pp. The slice has been taken
+// from a different P.
+// This is currently called when the world is stopped, but the caller
+// is expected to have locked the timers for pp.
+func moveTimers(pp *p, timers []*timer) {
+	for _, t := range timers {
+	loop:
+		for {
+			switch s := atomic.Load(&t.status); s {
+			case timerWaiting:
+				if !atomic.Cas(&t.status, s, timerMoving) {
+					continue
+				}
+				t.pp = 0
+				doaddtimer(pp, t)
+				if !atomic.Cas(&t.status, timerMoving, timerWaiting) {
+					badTimer()
+				}
+				break loop
+			case timerModifiedEarlier, timerModifiedLater:
+				if !atomic.Cas(&t.status, s, timerMoving) {
+					continue
+				}
+				t.when = t.nextwhen
+				t.pp = 0
+				doaddtimer(pp, t)
+				if !atomic.Cas(&t.status, timerMoving, timerWaiting) {
+					badTimer()
+				}
+				break loop
+			case timerDeleted:
+				if !atomic.Cas(&t.status, s, timerRemoved) {
+					continue
+				}
+				t.pp = 0
+				// We no longer need this timer in the heap.
+				break loop
+			case timerModifying:
+				// Loop until the modification is complete.
+				osyield()
+			case timerNoStatus, timerRemoved:
+				// We should not see these status values in a timers heap.
+				badTimer()
+			case timerRunning, timerRemoving, timerMoving:
+				// Some other P thinks it owns this timer,
+				// which should not happen.
+				badTimer()
+			default:
+				badTimer()
+			}
+		}
+	}
+}
+
+// adjusttimers looks through the timers in the current P's heap for
+// any timers that have been modified to run earlier, and puts them in
+// the correct place in the heap. While looking for those timers,
+// it also moves timers that have been modified to run later,
+// and removes deleted timers. The caller must have locked the timers for pp.
+func adjusttimers(pp *p, now int64) {
+	// If we haven't yet reached the time of the first timerModifiedEarlier
+	// timer, don't do anything. This speeds up programs that adjust
+	// a lot of timers back and forth if the timers rarely expire.
+	// We'll postpone looking through all the adjusted timers until
+	// one would actually expire.
+	first := atomic.Load64(&pp.timerModifiedEarliest)
+	if first == 0 || int64(first) > now {
+		if verifyTimers {
+			verifyTimerHeap(pp)
+		}
+		return
+	}
+
+	// We are going to clear all timerModifiedEarlier timers.
+	atomic.Store64(&pp.timerModifiedEarliest, 0)
+
+	var moved []*timer
+	for i := 0; i < len(pp.timers); i++ {
+		t := pp.timers[i]
+		if t.pp.ptr() != pp {
+			throw("adjusttimers: bad p")
+		}
+		switch s := atomic.Load(&t.status); s {
+		case timerDeleted:
+			if atomic.Cas(&t.status, s, timerRemoving) {
+				changed := dodeltimer(pp, i)
+				if !atomic.Cas(&t.status, timerRemoving, timerRemoved) {
+					badTimer()
+				}
+				atomic.Xadd(&pp.deletedTimers, -1)
+				// Go back to the earliest changed heap entry.
+				// "- 1" because the loop will add 1.
+				i = changed - 1
+			}
+		case timerModifiedEarlier, timerModifiedLater:
+			if atomic.Cas(&t.status, s, timerMoving) {
+				// Now we can change the when field.
+				t.when = t.nextwhen
+				// Take t off the heap, and hold onto it.
+				// We don't add it back yet because the
+				// heap manipulation could cause our
+				// loop to skip some other timer.
+				changed := dodeltimer(pp, i)
+				moved = append(moved, t)
+				// Go back to the earliest changed heap entry.
+				// "- 1" because the loop will add 1.
+				i = changed - 1
+			}
+		case timerNoStatus, timerRunning, timerRemoving, timerRemoved, timerMoving:
+			badTimer()
+		case timerWaiting:
+			// OK, nothing to do.
+		case timerModifying:
+			// Check again after modification is complete.
+			osyield()
+			i--
+		default:
+			badTimer()
+		}
+	}
+
+	if len(moved) > 0 {
+		addAdjustedTimers(pp, moved)
+	}
+
+	if verifyTimers {
+		verifyTimerHeap(pp)
+	}
+}
+
+// addAdjustedTimers adds any timers we adjusted in adjusttimers
+// back to the timer heap.
+func addAdjustedTimers(pp *p, moved []*timer) {
+	for _, t := range moved {
+		doaddtimer(pp, t)
+		if !atomic.Cas(&t.status, timerMoving, timerWaiting) {
+			badTimer()
+		}
+	}
+}
+
+// nobarrierWakeTime looks at P's timers and returns the time when we
+// should wake up the netpoller. It returns 0 if there are no timers.
+// This function is invoked when dropping a P, and must run without
+// any write barriers.
+//
+//go:nowritebarrierrec
+func nobarrierWakeTime(pp *p) int64 {
+	next := int64(atomic.Load64(&pp.timer0When))
+	nextAdj := int64(atomic.Load64(&pp.timerModifiedEarliest))
+	if next == 0 || (nextAdj != 0 && nextAdj < next) {
+		next = nextAdj
+	}
+	return next
+}
+
+// runtimer examines the first timer in timers. If it is ready based on now,
+// it runs the timer and removes or updates it.
+// Returns 0 if it ran a timer, -1 if there are no more timers, or the time
+// when the first timer should run.
+// The caller must have locked the timers for pp.
+// If a timer is run, this will temporarily unlock the timers.
+//
+//go:systemstack
+func runtimer(pp *p, now int64) int64 {
+	for {
+		t := pp.timers[0]
+		if t.pp.ptr() != pp {
+			throw("runtimer: bad p")
+		}
+		switch s := atomic.Load(&t.status); s {
+		case timerWaiting:
+			if t.when > now {
+				// Not ready to run.
+				return t.when
+			}
+
+			if !atomic.Cas(&t.status, s, timerRunning) {
+				continue
+			}
+			// Note that runOneTimer may temporarily unlock
+			// pp.timersLock.
+			runOneTimer(pp, t, now)
+			return 0
+
+		case timerDeleted:
+			if !atomic.Cas(&t.status, s, timerRemoving) {
+				continue
+			}
+			dodeltimer0(pp)
+			if !atomic.Cas(&t.status, timerRemoving, timerRemoved) {
+				badTimer()
+			}
+			atomic.Xadd(&pp.deletedTimers, -1)
+			if len(pp.timers) == 0 {
+				return -1
+			}
+
+		case timerModifiedEarlier, timerModifiedLater:
+			if !atomic.Cas(&t.status, s, timerMoving) {
+				continue
+			}
+			t.when = t.nextwhen
+			dodeltimer0(pp)
+			doaddtimer(pp, t)
+			if !atomic.Cas(&t.status, timerMoving, timerWaiting) {
+				badTimer()
+			}
+
+		case timerModifying:
+			// Wait for modification to complete.
+			osyield()
+
+		case timerNoStatus, timerRemoved:
+			// Should not see a new or inactive timer on the heap.
+			badTimer()
+		case timerRunning, timerRemoving, timerMoving:
+			// These should only be set when timers are locked,
+			// and we didn't do it.
+			badTimer()
+		default:
+			badTimer()
+		}
+	}
+}
+
+// runOneTimer runs a single timer.
+// The caller must have locked the timers for pp.
+// This will temporarily unlock the timers while running the timer function.
+//
+//go:systemstack
+func runOneTimer(pp *p, t *timer, now int64) {
+	if raceenabled {
+		ppcur := getg().m.p.ptr()
+		if ppcur.timerRaceCtx == 0 {
+			ppcur.timerRaceCtx = racegostart(abi.FuncPCABIInternal(runtimer) + sys.PCQuantum)
+		}
+		raceacquirectx(ppcur.timerRaceCtx, unsafe.Pointer(t))
+	}
+
+	f := t.f
+	arg := t.arg
+	seq := t.seq
+
+	if t.period > 0 {
+		// Leave in heap but adjust next time to fire.
+		delta := t.when - now
+		t.when += t.period * (1 + -delta/t.period)
+		if t.when < 0 { // check for overflow.
+			t.when = maxWhen
+		}
+		siftdownTimer(pp.timers, 0)
+		if !atomic.Cas(&t.status, timerRunning, timerWaiting) {
+			badTimer()
+		}
+		updateTimer0When(pp)
+	} else {
+		// Remove from heap.
+		dodeltimer0(pp)
+		if !atomic.Cas(&t.status, timerRunning, timerNoStatus) {
+			badTimer()
+		}
+	}
+
+	if raceenabled {
+		// Temporarily use the current P's racectx for g0.
+		gp := getg()
+		if gp.racectx != 0 {
+			throw("runOneTimer: unexpected racectx")
+		}
+		gp.racectx = gp.m.p.ptr().timerRaceCtx
+	}
+
+	unlock(&pp.timersLock)
+
+	f(arg, seq)
+
+	lock(&pp.timersLock)
+
+	if raceenabled {
+		gp := getg()
+		gp.racectx = 0
+	}
+}
+
+// clearDeletedTimers removes all deleted timers from the P's timer heap.
+// This is used to avoid clogging up the heap if the program
+// starts a lot of long-running timers and then stops them.
+// For example, this can happen via context.WithTimeout.
+//
+// This is the only function that walks through the entire timer heap,
+// other than moveTimers which only runs when the world is stopped.
+//
+// The caller must have locked the timers for pp.
+func clearDeletedTimers(pp *p) {
+	// We are going to clear all timerModifiedEarlier timers.
+	// Do this now in case new ones show up while we are looping.
+	atomic.Store64(&pp.timerModifiedEarliest, 0)
+
+	cdel := int32(0)
+	to := 0
+	changedHeap := false
+	timers := pp.timers
+nextTimer:
+	for _, t := range timers {
+		for {
+			switch s := atomic.Load(&t.status); s {
+			case timerWaiting:
+				if changedHeap {
+					timers[to] = t
+					siftupTimer(timers, to)
+				}
+				to++
+				continue nextTimer
+			case timerModifiedEarlier, timerModifiedLater:
+				if atomic.Cas(&t.status, s, timerMoving) {
+					t.when = t.nextwhen
+					timers[to] = t
+					siftupTimer(timers, to)
+					to++
+					changedHeap = true
+					if !atomic.Cas(&t.status, timerMoving, timerWaiting) {
+						badTimer()
+					}
+					continue nextTimer
+				}
+			case timerDeleted:
+				if atomic.Cas(&t.status, s, timerRemoving) {
+					t.pp = 0
+					cdel++
+					if !atomic.Cas(&t.status, timerRemoving, timerRemoved) {
+						badTimer()
+					}
+					changedHeap = true
+					continue nextTimer
+				}
+			case timerModifying:
+				// Loop until modification complete.
+				osyield()
+			case timerNoStatus, timerRemoved:
+				// We should not see these status values in a timer heap.
+				badTimer()
+			case timerRunning, timerRemoving, timerMoving:
+				// Some other P thinks it owns this timer,
+				// which should not happen.
+				badTimer()
+			default:
+				badTimer()
+			}
+		}
+	}
+
+	// Set remaining slots in timers slice to nil,
+	// so that the timer values can be garbage collected.
+	for i := to; i < len(timers); i++ {
+		timers[i] = nil
+	}
+
+	atomic.Xadd(&pp.deletedTimers, -cdel)
+	atomic.Xadd(&pp.numTimers, -cdel)
+
+	timers = timers[:to]
+	pp.timers = timers
+	updateTimer0When(pp)
+
+	if verifyTimers {
+		verifyTimerHeap(pp)
+	}
+}
+
+// verifyTimerHeap verifies that the timer heap is in a valid state.
+// This is only for debugging, and is only called if verifyTimers is true.
+// The caller must have locked the timers.
+func verifyTimerHeap(pp *p) {
+	for i, t := range pp.timers {
+		if i == 0 {
+			// First timer has no parent.
+			continue
+		}
+
+		// The heap is 4-ary. See siftupTimer and siftdownTimer.
+		p := (i - 1) / 4
+		if t.when < pp.timers[p].when {
+			print("bad timer heap at ", i, ": ", p, ": ", pp.timers[p].when, ", ", i, ": ", t.when, "\n")
+			throw("bad timer heap")
+		}
+	}
+	if numTimers := int(atomic.Load(&pp.numTimers)); len(pp.timers) != numTimers {
+		println("timer heap len", len(pp.timers), "!= numTimers", numTimers)
+		throw("bad timer heap len")
+	}
+}
+
+// updateTimer0When sets the P's timer0When field.
+// The caller must have locked the timers for pp.
+func updateTimer0When(pp *p) {
+	if len(pp.timers) == 0 {
+		atomic.Store64(&pp.timer0When, 0)
+	} else {
+		atomic.Store64(&pp.timer0When, uint64(pp.timers[0].when))
+	}
+}
+
+// updateTimerModifiedEarliest updates the recorded nextwhen field of the
+// earlier timerModifiedEarier value.
+// The timers for pp will not be locked.
+func updateTimerModifiedEarliest(pp *p, nextwhen int64) {
+	for {
+		old := atomic.Load64(&pp.timerModifiedEarliest)
+		if old != 0 && int64(old) < nextwhen {
+			return
+		}
+		if atomic.Cas64(&pp.timerModifiedEarliest, old, uint64(nextwhen)) {
+			return
+		}
+	}
+}
+
+// timeSleepUntil returns the time when the next timer should fire. Returns
+// maxWhen if there are no timers.
+// This is only called by sysmon and checkdead.
+func timeSleepUntil() int64 {
+	next := int64(maxWhen)
+
+	// Prevent allp slice changes. This is like retake.
+	lock(&allpLock)
+	for _, pp := range allp {
+		if pp == nil {
+			// This can happen if procresize has grown
+			// allp but not yet created new Ps.
+			continue
+		}
+
+		w := int64(atomic.Load64(&pp.timer0When))
+		if w != 0 && w < next {
+			next = w
+		}
+
+		w = int64(atomic.Load64(&pp.timerModifiedEarliest))
+		if w != 0 && w < next {
+			next = w
+		}
+	}
+	unlock(&allpLock)
+
+	return next
+}
+
+// Heap maintenance algorithms.
+// These algorithms check for slice index errors manually.
+// Slice index error can happen if the program is using racy
+// access to timers. We don't want to panic here, because
+// it will cause the program to crash with a mysterious
+// "panic holding locks" message. Instead, we panic while not
+// holding a lock.
+
+// siftupTimer puts the timer at position i in the right place
+// in the heap by moving it up toward the top of the heap.
+// It returns the smallest changed index.
+func siftupTimer(t []*timer, i int) int {
+	if i >= len(t) {
+		badTimer()
+	}
+	when := t[i].when
+	if when <= 0 {
+		badTimer()
+	}
+	tmp := t[i]
+	for i > 0 {
+		p := (i - 1) / 4 // parent
+		if when >= t[p].when {
+			break
+		}
+		t[i] = t[p]
+		i = p
+	}
+	if tmp != t[i] {
+		t[i] = tmp
+	}
+	return i
+}
+
+// siftdownTimer puts the timer at position i in the right place
+// in the heap by moving it down toward the bottom of the heap.
+func siftdownTimer(t []*timer, i int) {
+	n := len(t)
+	if i >= n {
+		badTimer()
+	}
+	when := t[i].when
+	if when <= 0 {
+		badTimer()
+	}
+	tmp := t[i]
+	for {
+		c := i*4 + 1 // left child
+		c3 := c + 2  // mid child
+		if c >= n {
+			break
+		}
+		w := t[c].when
+		if c+1 < n && t[c+1].when < w {
+			w = t[c+1].when
+			c++
+		}
+		if c3 < n {
+			w3 := t[c3].when
+			if c3+1 < n && t[c3+1].when < w3 {
+				w3 = t[c3+1].when
+				c3++
+			}
+			if w3 < w {
+				w = w3
+				c = c3
+			}
+		}
+		if w >= when {
+			break
+		}
+		t[i] = t[c]
+		i = c
+	}
+	if tmp != t[i] {
+		t[i] = tmp
+	}
+}
+
+// badTimer is called if the timer data structures have been corrupted,
+// presumably due to racy use by the program. We panic here rather than
+// panicing due to invalid slice access while holding locks.
+// See issue #25686.
+func badTimer() {
+	throw("timer data corruption")
+}
diff --git a/contrib/go/_std_1.18/src/runtime/time_linux_amd64.s b/contrib/go/_std_1.19/src/runtime/time_linux_amd64.s
index 1416d23230..1416d23230 100644
--- a/contrib/go/_std_1.18/src/runtime/time_linux_amd64.s
+++ b/contrib/go/_std_1.19/src/runtime/time_linux_amd64.s
diff --git a/contrib/go/_std_1.18/src/runtime/time_nofake.go b/contrib/go/_std_1.19/src/runtime/time_nofake.go
index 70a2102b22..70a2102b22 100644
--- a/contrib/go/_std_1.18/src/runtime/time_nofake.go
+++ b/contrib/go/_std_1.19/src/runtime/time_nofake.go
diff --git a/contrib/go/_std_1.18/src/runtime/timeasm.go b/contrib/go/_std_1.19/src/runtime/timeasm.go
index 0421388686..0421388686 100644
--- a/contrib/go/_std_1.18/src/runtime/timeasm.go
+++ b/contrib/go/_std_1.19/src/runtime/timeasm.go
diff --git a/contrib/go/_std_1.18/src/runtime/timestub.go b/contrib/go/_std_1.19/src/runtime/timestub.go
index 1d2926b43d..1d2926b43d 100644
--- a/contrib/go/_std_1.18/src/runtime/timestub.go
+++ b/contrib/go/_std_1.19/src/runtime/timestub.go
diff --git a/contrib/go/_std_1.18/src/runtime/tls_stub.go b/contrib/go/_std_1.19/src/runtime/tls_stub.go
index 7bdfc6b89a..7bdfc6b89a 100644
--- a/contrib/go/_std_1.18/src/runtime/tls_stub.go
+++ b/contrib/go/_std_1.19/src/runtime/tls_stub.go
diff --git a/contrib/go/_std_1.19/src/runtime/trace.go b/contrib/go/_std_1.19/src/runtime/trace.go
new file mode 100644
index 0000000000..10436d80c2
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/trace.go
@@ -0,0 +1,1442 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Go execution tracer.
+// The tracer captures a wide range of execution events like goroutine
+// creation/blocking/unblocking, syscall enter/exit/block, GC-related events,
+// changes of heap size, processor start/stop, etc and writes them to a buffer
+// in a compact form. A precise nanosecond-precision timestamp and a stack
+// trace is captured for most events.
+// See https://golang.org/s/go15trace for more info.
+
+package runtime
+
+import (
+	"internal/goarch"
+	"runtime/internal/atomic"
+	"runtime/internal/sys"
+	"unsafe"
+)
+
+// Event types in the trace, args are given in square brackets.
+const (
+	traceEvNone              = 0  // unused
+	traceEvBatch             = 1  // start of per-P batch of events [pid, timestamp]
+	traceEvFrequency         = 2  // contains tracer timer frequency [frequency (ticks per second)]
+	traceEvStack             = 3  // stack [stack id, number of PCs, array of {PC, func string ID, file string ID, line}]
+	traceEvGomaxprocs        = 4  // current value of GOMAXPROCS [timestamp, GOMAXPROCS, stack id]
+	traceEvProcStart         = 5  // start of P [timestamp, thread id]
+	traceEvProcStop          = 6  // stop of P [timestamp]
+	traceEvGCStart           = 7  // GC start [timestamp, seq, stack id]
+	traceEvGCDone            = 8  // GC done [timestamp]
+	traceEvGCSTWStart        = 9  // GC STW start [timestamp, kind]
+	traceEvGCSTWDone         = 10 // GC STW done [timestamp]
+	traceEvGCSweepStart      = 11 // GC sweep start [timestamp, stack id]
+	traceEvGCSweepDone       = 12 // GC sweep done [timestamp, swept, reclaimed]
+	traceEvGoCreate          = 13 // goroutine creation [timestamp, new goroutine id, new stack id, stack id]
+	traceEvGoStart           = 14 // goroutine starts running [timestamp, goroutine id, seq]
+	traceEvGoEnd             = 15 // goroutine ends [timestamp]
+	traceEvGoStop            = 16 // goroutine stops (like in select{}) [timestamp, stack]
+	traceEvGoSched           = 17 // goroutine calls Gosched [timestamp, stack]
+	traceEvGoPreempt         = 18 // goroutine is preempted [timestamp, stack]
+	traceEvGoSleep           = 19 // goroutine calls Sleep [timestamp, stack]
+	traceEvGoBlock           = 20 // goroutine blocks [timestamp, stack]
+	traceEvGoUnblock         = 21 // goroutine is unblocked [timestamp, goroutine id, seq, stack]
+	traceEvGoBlockSend       = 22 // goroutine blocks on chan send [timestamp, stack]
+	traceEvGoBlockRecv       = 23 // goroutine blocks on chan recv [timestamp, stack]
+	traceEvGoBlockSelect     = 24 // goroutine blocks on select [timestamp, stack]
+	traceEvGoBlockSync       = 25 // goroutine blocks on Mutex/RWMutex [timestamp, stack]
+	traceEvGoBlockCond       = 26 // goroutine blocks on Cond [timestamp, stack]
+	traceEvGoBlockNet        = 27 // goroutine blocks on network [timestamp, stack]
+	traceEvGoSysCall         = 28 // syscall enter [timestamp, stack]
+	traceEvGoSysExit         = 29 // syscall exit [timestamp, goroutine id, seq, real timestamp]
+	traceEvGoSysBlock        = 30 // syscall blocks [timestamp]
+	traceEvGoWaiting         = 31 // denotes that goroutine is blocked when tracing starts [timestamp, goroutine id]
+	traceEvGoInSyscall       = 32 // denotes that goroutine is in syscall when tracing starts [timestamp, goroutine id]
+	traceEvHeapAlloc         = 33 // gcController.heapLive change [timestamp, heap_alloc]
+	traceEvHeapGoal          = 34 // gcController.heapGoal() (formerly next_gc) change [timestamp, heap goal in bytes]
+	traceEvTimerGoroutine    = 35 // not currently used; previously denoted timer goroutine [timer goroutine id]
+	traceEvFutileWakeup      = 36 // denotes that the previous wakeup of this goroutine was futile [timestamp]
+	traceEvString            = 37 // string dictionary entry [ID, length, string]
+	traceEvGoStartLocal      = 38 // goroutine starts running on the same P as the last event [timestamp, goroutine id]
+	traceEvGoUnblockLocal    = 39 // goroutine is unblocked on the same P as the last event [timestamp, goroutine id, stack]
+	traceEvGoSysExitLocal    = 40 // syscall exit on the same P as the last event [timestamp, goroutine id, real timestamp]
+	traceEvGoStartLabel      = 41 // goroutine starts running with label [timestamp, goroutine id, seq, label string id]
+	traceEvGoBlockGC         = 42 // goroutine blocks on GC assist [timestamp, stack]
+	traceEvGCMarkAssistStart = 43 // GC mark assist start [timestamp, stack]
+	traceEvGCMarkAssistDone  = 44 // GC mark assist done [timestamp]
+	traceEvUserTaskCreate    = 45 // trace.NewContext [timestamp, internal task id, internal parent task id, stack, name string]
+	traceEvUserTaskEnd       = 46 // end of a task [timestamp, internal task id, stack]
+	traceEvUserRegion        = 47 // trace.WithRegion [timestamp, internal task id, mode(0:start, 1:end), stack, name string]
+	traceEvUserLog           = 48 // trace.Log [timestamp, internal task id, key string id, stack, value string]
+	traceEvCPUSample         = 49 // CPU profiling sample [timestamp, stack, real timestamp, real P id (-1 when absent), goroutine id]
+	traceEvCount             = 50
+	// Byte is used but only 6 bits are available for event type.
+	// The remaining 2 bits are used to specify the number of arguments.
+	// That means, the max event type value is 63.
+)
+
+const (
+	// Timestamps in trace are cputicks/traceTickDiv.
+	// This makes absolute values of timestamp diffs smaller,
+	// and so they are encoded in less number of bytes.
+	// 64 on x86 is somewhat arbitrary (one tick is ~20ns on a 3GHz machine).
+	// The suggested increment frequency for PowerPC's time base register is
+	// 512 MHz according to Power ISA v2.07 section 6.2, so we use 16 on ppc64
+	// and ppc64le.
+	// Tracing won't work reliably for architectures where cputicks is emulated
+	// by nanotime, so the value doesn't matter for those architectures.
+	traceTickDiv = 16 + 48*(goarch.Is386|goarch.IsAmd64)
+	// Maximum number of PCs in a single stack trace.
+	// Since events contain only stack id rather than whole stack trace,
+	// we can allow quite large values here.
+	traceStackSize = 128
+	// Identifier of a fake P that is used when we trace without a real P.
+	traceGlobProc = -1
+	// Maximum number of bytes to encode uint64 in base-128.
+	traceBytesPerNumber = 10
+	// Shift of the number of arguments in the first event byte.
+	traceArgCountShift = 6
+	// Flag passed to traceGoPark to denote that the previous wakeup of this
+	// goroutine was futile. For example, a goroutine was unblocked on a mutex,
+	// but another goroutine got ahead and acquired the mutex before the first
+	// goroutine is scheduled, so the first goroutine has to block again.
+	// Such wakeups happen on buffered channels and sync.Mutex,
+	// but are generally not interesting for end user.
+	traceFutileWakeup byte = 128
+)
+
+// trace is global tracing context.
+var trace struct {
+	lock          mutex       // protects the following members
+	lockOwner     *g          // to avoid deadlocks during recursive lock locks
+	enabled       bool        // when set runtime traces events
+	shutdown      bool        // set when we are waiting for trace reader to finish after setting enabled to false
+	headerWritten bool        // whether ReadTrace has emitted trace header
+	footerWritten bool        // whether ReadTrace has emitted trace footer
+	shutdownSema  uint32      // used to wait for ReadTrace completion
+	seqStart      uint64      // sequence number when tracing was started
+	ticksStart    int64       // cputicks when tracing was started
+	ticksEnd      int64       // cputicks when tracing was stopped
+	timeStart     int64       // nanotime when tracing was started
+	timeEnd       int64       // nanotime when tracing was stopped
+	seqGC         uint64      // GC start/done sequencer
+	reading       traceBufPtr // buffer currently handed off to user
+	empty         traceBufPtr // stack of empty buffers
+	fullHead      traceBufPtr // queue of full buffers
+	fullTail      traceBufPtr
+	reader        guintptr        // goroutine that called ReadTrace, or nil
+	stackTab      traceStackTable // maps stack traces to unique ids
+	// cpuLogRead accepts CPU profile samples from the signal handler where
+	// they're generated. It uses a two-word header to hold the IDs of the P and
+	// G (respectively) that were active at the time of the sample. Because
+	// profBuf uses a record with all zeros in its header to indicate overflow,
+	// we make sure to make the P field always non-zero: The ID of a real P will
+	// start at bit 1, and bit 0 will be set. Samples that arrive while no P is
+	// running (such as near syscalls) will set the first header field to 0b10.
+	// This careful handling of the first header field allows us to store ID of
+	// the active G directly in the second field, even though that will be 0
+	// when sampling g0.
+	cpuLogRead *profBuf
+	// cpuLogBuf is a trace buffer to hold events corresponding to CPU profile
+	// samples, which arrive out of band and not directly connected to a
+	// specific P.
+	cpuLogBuf traceBufPtr
+
+	signalLock  atomic.Uint32 // protects use of the following member, only usable in signal handlers
+	cpuLogWrite *profBuf      // copy of cpuLogRead for use in signal handlers, set without signalLock
+
+	// Dictionary for traceEvString.
+	//
+	// TODO: central lock to access the map is not ideal.
+	//   option: pre-assign ids to all user annotation region names and tags
+	//   option: per-P cache
+	//   option: sync.Map like data structure
+	stringsLock mutex
+	strings     map[string]uint64
+	stringSeq   uint64
+
+	// markWorkerLabels maps gcMarkWorkerMode to string ID.
+	markWorkerLabels [len(gcMarkWorkerModeStrings)]uint64
+
+	bufLock mutex       // protects buf
+	buf     traceBufPtr // global trace buffer, used when running without a p
+}
+
+// traceBufHeader is per-P tracing buffer.
+type traceBufHeader struct {
+	link      traceBufPtr             // in trace.empty/full
+	lastTicks uint64                  // when we wrote the last event
+	pos       int                     // next write offset in arr
+	stk       [traceStackSize]uintptr // scratch buffer for traceback
+}
+
+// traceBuf is per-P tracing buffer.
+//
+//go:notinheap
+type traceBuf struct {
+	traceBufHeader
+	arr [64<<10 - unsafe.Sizeof(traceBufHeader{})]byte // underlying buffer for traceBufHeader.buf
+}
+
+// traceBufPtr is a *traceBuf that is not traced by the garbage
+// collector and doesn't have write barriers. traceBufs are not
+// allocated from the GC'd heap, so this is safe, and are often
+// manipulated in contexts where write barriers are not allowed, so
+// this is necessary.
+//
+// TODO: Since traceBuf is now go:notinheap, this isn't necessary.
+type traceBufPtr uintptr
+
+func (tp traceBufPtr) ptr() *traceBuf   { return (*traceBuf)(unsafe.Pointer(tp)) }
+func (tp *traceBufPtr) set(b *traceBuf) { *tp = traceBufPtr(unsafe.Pointer(b)) }
+func traceBufPtrOf(b *traceBuf) traceBufPtr {
+	return traceBufPtr(unsafe.Pointer(b))
+}
+
+// StartTrace enables tracing for the current process.
+// While tracing, the data will be buffered and available via ReadTrace.
+// StartTrace returns an error if tracing is already enabled.
+// Most clients should use the runtime/trace package or the testing package's
+// -test.trace flag instead of calling StartTrace directly.
+func StartTrace() error {
+	// Stop the world so that we can take a consistent snapshot
+	// of all goroutines at the beginning of the trace.
+	// Do not stop the world during GC so we ensure we always see
+	// a consistent view of GC-related events (e.g. a start is always
+	// paired with an end).
+	stopTheWorldGC("start tracing")
+
+	// Prevent sysmon from running any code that could generate events.
+	lock(&sched.sysmonlock)
+
+	// We are in stop-the-world, but syscalls can finish and write to trace concurrently.
+	// Exitsyscall could check trace.enabled long before and then suddenly wake up
+	// and decide to write to trace at a random point in time.
+	// However, such syscall will use the global trace.buf buffer, because we've
+	// acquired all p's by doing stop-the-world. So this protects us from such races.
+	lock(&trace.bufLock)
+
+	if trace.enabled || trace.shutdown {
+		unlock(&trace.bufLock)
+		unlock(&sched.sysmonlock)
+		startTheWorldGC()
+		return errorString("tracing is already enabled")
+	}
+
+	// Can't set trace.enabled yet. While the world is stopped, exitsyscall could
+	// already emit a delayed event (see exitTicks in exitsyscall) if we set trace.enabled here.
+	// That would lead to an inconsistent trace:
+	// - either GoSysExit appears before EvGoInSyscall,
+	// - or GoSysExit appears for a goroutine for which we don't emit EvGoInSyscall below.
+	// To instruct traceEvent that it must not ignore events below, we set startingtrace.
+	// trace.enabled is set afterwards once we have emitted all preliminary events.
+	_g_ := getg()
+	_g_.m.startingtrace = true
+
+	// Obtain current stack ID to use in all traceEvGoCreate events below.
+	mp := acquirem()
+	stkBuf := make([]uintptr, traceStackSize)
+	stackID := traceStackID(mp, stkBuf, 2)
+	releasem(mp)
+
+	profBuf := newProfBuf(2, profBufWordCount, profBufTagCount) // after the timestamp, header is [pp.id, gp.goid]
+	trace.cpuLogRead = profBuf
+
+	// We must not acquire trace.signalLock outside of a signal handler: a
+	// profiling signal may arrive at any time and try to acquire it, leading to
+	// deadlock. Because we can't use that lock to protect updates to
+	// trace.cpuLogWrite (only use of the structure it references), reads and
+	// writes of the pointer must be atomic. (And although this field is never
+	// the sole pointer to the profBuf value, it's best to allow a write barrier
+	// here.)
+	atomicstorep(unsafe.Pointer(&trace.cpuLogWrite), unsafe.Pointer(profBuf))
+
+	// World is stopped, no need to lock.
+	forEachGRace(func(gp *g) {
+		status := readgstatus(gp)
+		if status != _Gdead {
+			gp.traceseq = 0
+			gp.tracelastp = getg().m.p
+			// +PCQuantum because traceFrameForPC expects return PCs and subtracts PCQuantum.
+			id := trace.stackTab.put([]uintptr{startPCforTrace(gp.startpc) + sys.PCQuantum})
+			traceEvent(traceEvGoCreate, -1, uint64(gp.goid), uint64(id), stackID)
+		}
+		if status == _Gwaiting {
+			// traceEvGoWaiting is implied to have seq=1.
+			gp.traceseq++
+			traceEvent(traceEvGoWaiting, -1, uint64(gp.goid))
+		}
+		if status == _Gsyscall {
+			gp.traceseq++
+			traceEvent(traceEvGoInSyscall, -1, uint64(gp.goid))
+		} else {
+			gp.sysblocktraced = false
+		}
+	})
+	traceProcStart()
+	traceGoStart()
+	// Note: ticksStart needs to be set after we emit traceEvGoInSyscall events.
+	// If we do it the other way around, it is possible that exitsyscall will
+	// query sysexitticks after ticksStart but before traceEvGoInSyscall timestamp.
+	// It will lead to a false conclusion that cputicks is broken.
+	trace.ticksStart = cputicks()
+	trace.timeStart = nanotime()
+	trace.headerWritten = false
+	trace.footerWritten = false
+
+	// string to id mapping
+	//  0 : reserved for an empty string
+	//  remaining: other strings registered by traceString
+	trace.stringSeq = 0
+	trace.strings = make(map[string]uint64)
+
+	trace.seqGC = 0
+	_g_.m.startingtrace = false
+	trace.enabled = true
+
+	// Register runtime goroutine labels.
+	_, pid, bufp := traceAcquireBuffer()
+	for i, label := range gcMarkWorkerModeStrings[:] {
+		trace.markWorkerLabels[i], bufp = traceString(bufp, pid, label)
+	}
+	traceReleaseBuffer(pid)
+
+	unlock(&trace.bufLock)
+
+	unlock(&sched.sysmonlock)
+
+	startTheWorldGC()
+	return nil
+}
+
+// StopTrace stops tracing, if it was previously enabled.
+// StopTrace only returns after all the reads for the trace have completed.
+func StopTrace() {
+	// Stop the world so that we can collect the trace buffers from all p's below,
+	// and also to avoid races with traceEvent.
+	stopTheWorldGC("stop tracing")
+
+	// See the comment in StartTrace.
+	lock(&sched.sysmonlock)
+
+	// See the comment in StartTrace.
+	lock(&trace.bufLock)
+
+	if !trace.enabled {
+		unlock(&trace.bufLock)
+		unlock(&sched.sysmonlock)
+		startTheWorldGC()
+		return
+	}
+
+	traceGoSched()
+
+	atomicstorep(unsafe.Pointer(&trace.cpuLogWrite), nil)
+	trace.cpuLogRead.close()
+	traceReadCPU()
+
+	// Loop over all allocated Ps because dead Ps may still have
+	// trace buffers.
+	for _, p := range allp[:cap(allp)] {
+		buf := p.tracebuf
+		if buf != 0 {
+			traceFullQueue(buf)
+			p.tracebuf = 0
+		}
+	}
+	if trace.buf != 0 {
+		buf := trace.buf
+		trace.buf = 0
+		if buf.ptr().pos != 0 {
+			traceFullQueue(buf)
+		}
+	}
+	if trace.cpuLogBuf != 0 {
+		buf := trace.cpuLogBuf
+		trace.cpuLogBuf = 0
+		if buf.ptr().pos != 0 {
+			traceFullQueue(buf)
+		}
+	}
+
+	for {
+		trace.ticksEnd = cputicks()
+		trace.timeEnd = nanotime()
+		// Windows time can tick only every 15ms, wait for at least one tick.
+		if trace.timeEnd != trace.timeStart {
+			break
+		}
+		osyield()
+	}
+
+	trace.enabled = false
+	trace.shutdown = true
+	unlock(&trace.bufLock)
+
+	unlock(&sched.sysmonlock)
+
+	startTheWorldGC()
+
+	// The world is started but we've set trace.shutdown, so new tracing can't start.
+	// Wait for the trace reader to flush pending buffers and stop.
+	semacquire(&trace.shutdownSema)
+	if raceenabled {
+		raceacquire(unsafe.Pointer(&trace.shutdownSema))
+	}
+
+	// The lock protects us from races with StartTrace/StopTrace because they do stop-the-world.
+	lock(&trace.lock)
+	for _, p := range allp[:cap(allp)] {
+		if p.tracebuf != 0 {
+			throw("trace: non-empty trace buffer in proc")
+		}
+	}
+	if trace.buf != 0 {
+		throw("trace: non-empty global trace buffer")
+	}
+	if trace.fullHead != 0 || trace.fullTail != 0 {
+		throw("trace: non-empty full trace buffer")
+	}
+	if trace.reading != 0 || trace.reader != 0 {
+		throw("trace: reading after shutdown")
+	}
+	for trace.empty != 0 {
+		buf := trace.empty
+		trace.empty = buf.ptr().link
+		sysFree(unsafe.Pointer(buf), unsafe.Sizeof(*buf.ptr()), &memstats.other_sys)
+	}
+	trace.strings = nil
+	trace.shutdown = false
+	trace.cpuLogRead = nil
+	unlock(&trace.lock)
+}
+
+// ReadTrace returns the next chunk of binary tracing data, blocking until data
+// is available. If tracing is turned off and all the data accumulated while it
+// was on has been returned, ReadTrace returns nil. The caller must copy the
+// returned data before calling ReadTrace again.
+// ReadTrace must be called from one goroutine at a time.
+func ReadTrace() []byte {
+	// This function may need to lock trace.lock recursively
+	// (goparkunlock -> traceGoPark -> traceEvent -> traceFlush).
+	// To allow this we use trace.lockOwner.
+	// Also this function must not allocate while holding trace.lock:
+	// allocation can call heap allocate, which will try to emit a trace
+	// event while holding heap lock.
+	lock(&trace.lock)
+	trace.lockOwner = getg()
+
+	if trace.reader != 0 {
+		// More than one goroutine reads trace. This is bad.
+		// But we rather do not crash the program because of tracing,
+		// because tracing can be enabled at runtime on prod servers.
+		trace.lockOwner = nil
+		unlock(&trace.lock)
+		println("runtime: ReadTrace called from multiple goroutines simultaneously")
+		return nil
+	}
+	// Recycle the old buffer.
+	if buf := trace.reading; buf != 0 {
+		buf.ptr().link = trace.empty
+		trace.empty = buf
+		trace.reading = 0
+	}
+	// Write trace header.
+	if !trace.headerWritten {
+		trace.headerWritten = true
+		trace.lockOwner = nil
+		unlock(&trace.lock)
+		return []byte("go 1.19 trace\x00\x00\x00")
+	}
+	// Optimistically look for CPU profile samples. This may write new stack
+	// records, and may write new tracing buffers.
+	if !trace.footerWritten && !trace.shutdown {
+		traceReadCPU()
+	}
+	// Wait for new data.
+	if trace.fullHead == 0 && !trace.shutdown {
+		trace.reader.set(getg())
+		goparkunlock(&trace.lock, waitReasonTraceReaderBlocked, traceEvGoBlock, 2)
+		lock(&trace.lock)
+	}
+	// Write a buffer.
+	if trace.fullHead != 0 {
+		buf := traceFullDequeue()
+		trace.reading = buf
+		trace.lockOwner = nil
+		unlock(&trace.lock)
+		return buf.ptr().arr[:buf.ptr().pos]
+	}
+
+	// Write footer with timer frequency.
+	if !trace.footerWritten {
+		trace.footerWritten = true
+		// Use float64 because (trace.ticksEnd - trace.ticksStart) * 1e9 can overflow int64.
+		freq := float64(trace.ticksEnd-trace.ticksStart) * 1e9 / float64(trace.timeEnd-trace.timeStart) / traceTickDiv
+		if freq <= 0 {
+			throw("trace: ReadTrace got invalid frequency")
+		}
+		trace.lockOwner = nil
+		unlock(&trace.lock)
+		var data []byte
+		data = append(data, traceEvFrequency|0<<traceArgCountShift)
+		data = traceAppend(data, uint64(freq))
+		// This will emit a bunch of full buffers, we will pick them up
+		// on the next iteration.
+		trace.stackTab.dump()
+		return data
+	}
+	// Done.
+	if trace.shutdown {
+		trace.lockOwner = nil
+		unlock(&trace.lock)
+		if raceenabled {
+			// Model synchronization on trace.shutdownSema, which race
+			// detector does not see. This is required to avoid false
+			// race reports on writer passed to trace.Start.
+			racerelease(unsafe.Pointer(&trace.shutdownSema))
+		}
+		// trace.enabled is already reset, so can call traceable functions.
+		semrelease(&trace.shutdownSema)
+		return nil
+	}
+	// Also bad, but see the comment above.
+	trace.lockOwner = nil
+	unlock(&trace.lock)
+	println("runtime: spurious wakeup of trace reader")
+	return nil
+}
+
+// traceReader returns the trace reader that should be woken up, if any.
+// Callers should first check that trace.enabled or trace.shutdown is set.
+func traceReader() *g {
+	if !traceReaderAvailable() {
+		return nil
+	}
+	lock(&trace.lock)
+	if !traceReaderAvailable() {
+		unlock(&trace.lock)
+		return nil
+	}
+	gp := trace.reader.ptr()
+	trace.reader.set(nil)
+	unlock(&trace.lock)
+	return gp
+}
+
+// traceReaderAvailable returns true if the trace reader is not currently
+// scheduled and should be. Callers should first check that trace.enabled
+// or trace.shutdown is set.
+func traceReaderAvailable() bool {
+	return trace.reader != 0 && (trace.fullHead != 0 || trace.shutdown)
+}
+
+// traceProcFree frees trace buffer associated with pp.
+func traceProcFree(pp *p) {
+	buf := pp.tracebuf
+	pp.tracebuf = 0
+	if buf == 0 {
+		return
+	}
+	lock(&trace.lock)
+	traceFullQueue(buf)
+	unlock(&trace.lock)
+}
+
+// traceFullQueue queues buf into queue of full buffers.
+func traceFullQueue(buf traceBufPtr) {
+	buf.ptr().link = 0
+	if trace.fullHead == 0 {
+		trace.fullHead = buf
+	} else {
+		trace.fullTail.ptr().link = buf
+	}
+	trace.fullTail = buf
+}
+
+// traceFullDequeue dequeues from queue of full buffers.
+func traceFullDequeue() traceBufPtr {
+	buf := trace.fullHead
+	if buf == 0 {
+		return 0
+	}
+	trace.fullHead = buf.ptr().link
+	if trace.fullHead == 0 {
+		trace.fullTail = 0
+	}
+	buf.ptr().link = 0
+	return buf
+}
+
+// traceEvent writes a single event to trace buffer, flushing the buffer if necessary.
+// ev is event type.
+// If skip > 0, write current stack id as the last argument (skipping skip top frames).
+// If skip = 0, this event type should contain a stack, but we don't want
+// to collect and remember it for this particular call.
+func traceEvent(ev byte, skip int, args ...uint64) {
+	mp, pid, bufp := traceAcquireBuffer()
+	// Double-check trace.enabled now that we've done m.locks++ and acquired bufLock.
+	// This protects from races between traceEvent and StartTrace/StopTrace.
+
+	// The caller checked that trace.enabled == true, but trace.enabled might have been
+	// turned off between the check and now. Check again. traceLockBuffer did mp.locks++,
+	// StopTrace does stopTheWorld, and stopTheWorld waits for mp.locks to go back to zero,
+	// so if we see trace.enabled == true now, we know it's true for the rest of the function.
+	// Exitsyscall can run even during stopTheWorld. The race with StartTrace/StopTrace
+	// during tracing in exitsyscall is resolved by locking trace.bufLock in traceLockBuffer.
+	//
+	// Note trace_userTaskCreate runs the same check.
+	if !trace.enabled && !mp.startingtrace {
+		traceReleaseBuffer(pid)
+		return
+	}
+
+	if skip > 0 {
+		if getg() == mp.curg {
+			skip++ // +1 because stack is captured in traceEventLocked.
+		}
+	}
+	traceEventLocked(0, mp, pid, bufp, ev, 0, skip, args...)
+	traceReleaseBuffer(pid)
+}
+
+// traceEventLocked writes a single event of type ev to the trace buffer bufp,
+// flushing the buffer if necessary. pid is the id of the current P, or
+// traceGlobProc if we're tracing without a real P.
+//
+// Preemption is disabled, and if running without a real P the global tracing
+// buffer is locked.
+//
+// Events types that do not include a stack set skip to -1. Event types that
+// include a stack may explicitly reference a stackID from the trace.stackTab
+// (obtained by an earlier call to traceStackID). Without an explicit stackID,
+// this function will automatically capture the stack of the goroutine currently
+// running on mp, skipping skip top frames or, if skip is 0, writing out an
+// empty stack record.
+//
+// It records the event's args to the traceBuf, and also makes an effort to
+// reserve extraBytes bytes of additional space immediately following the event,
+// in the same traceBuf.
+func traceEventLocked(extraBytes int, mp *m, pid int32, bufp *traceBufPtr, ev byte, stackID uint32, skip int, args ...uint64) {
+	buf := bufp.ptr()
+	// TODO: test on non-zero extraBytes param.
+	maxSize := 2 + 5*traceBytesPerNumber + extraBytes // event type, length, sequence, timestamp, stack id and two add params
+	if buf == nil || len(buf.arr)-buf.pos < maxSize {
+		buf = traceFlush(traceBufPtrOf(buf), pid).ptr()
+		bufp.set(buf)
+	}
+
+	// NOTE: ticks might be same after tick division, although the real cputicks is
+	// linear growth.
+	ticks := uint64(cputicks()) / traceTickDiv
+	tickDiff := ticks - buf.lastTicks
+	if tickDiff == 0 {
+		ticks = buf.lastTicks + 1
+		tickDiff = 1
+	}
+
+	buf.lastTicks = ticks
+	narg := byte(len(args))
+	if stackID != 0 || skip >= 0 {
+		narg++
+	}
+	// We have only 2 bits for number of arguments.
+	// If number is >= 3, then the event type is followed by event length in bytes.
+	if narg > 3 {
+		narg = 3
+	}
+	startPos := buf.pos
+	buf.byte(ev | narg<<traceArgCountShift)
+	var lenp *byte
+	if narg == 3 {
+		// Reserve the byte for length assuming that length < 128.
+		buf.varint(0)
+		lenp = &buf.arr[buf.pos-1]
+	}
+	buf.varint(tickDiff)
+	for _, a := range args {
+		buf.varint(a)
+	}
+	if stackID != 0 {
+		buf.varint(uint64(stackID))
+	} else if skip == 0 {
+		buf.varint(0)
+	} else if skip > 0 {
+		buf.varint(traceStackID(mp, buf.stk[:], skip))
+	}
+	evSize := buf.pos - startPos
+	if evSize > maxSize {
+		throw("invalid length of trace event")
+	}
+	if lenp != nil {
+		// Fill in actual length.
+		*lenp = byte(evSize - 2)
+	}
+}
+
+// traceCPUSample writes a CPU profile sample stack to the execution tracer's
+// profiling buffer. It is called from a signal handler, so is limited in what
+// it can do.
+func traceCPUSample(gp *g, pp *p, stk []uintptr) {
+	if !trace.enabled {
+		// Tracing is usually turned off; don't spend time acquiring the signal
+		// lock unless it's active.
+		return
+	}
+
+	// Match the clock used in traceEventLocked
+	now := cputicks()
+	// The "header" here is the ID of the P that was running the profiled code,
+	// followed by the ID of the goroutine. (For normal CPU profiling, it's
+	// usually the number of samples with the given stack.) Near syscalls, pp
+	// may be nil. Reporting goid of 0 is fine for either g0 or a nil gp.
+	var hdr [2]uint64
+	if pp != nil {
+		// Overflow records in profBuf have all header values set to zero. Make
+		// sure that real headers have at least one bit set.
+		hdr[0] = uint64(pp.id)<<1 | 0b1
+	} else {
+		hdr[0] = 0b10
+	}
+	if gp != nil {
+		hdr[1] = uint64(gp.goid)
+	}
+
+	// Allow only one writer at a time
+	for !trace.signalLock.CompareAndSwap(0, 1) {
+		// TODO: Is it safe to osyield here? https://go.dev/issue/52672
+		osyield()
+	}
+
+	if log := (*profBuf)(atomic.Loadp(unsafe.Pointer(&trace.cpuLogWrite))); log != nil {
+		// Note: we don't pass a tag pointer here (how should profiling tags
+		// interact with the execution tracer?), but if we did we'd need to be
+		// careful about write barriers. See the long comment in profBuf.write.
+		log.write(nil, now, hdr[:], stk)
+	}
+
+	trace.signalLock.Store(0)
+}
+
+func traceReadCPU() {
+	bufp := &trace.cpuLogBuf
+
+	for {
+		data, tags, _ := trace.cpuLogRead.read(profBufNonBlocking)
+		if len(data) == 0 {
+			break
+		}
+		for len(data) > 0 {
+			if len(data) < 4 || data[0] > uint64(len(data)) {
+				break // truncated profile
+			}
+			if data[0] < 4 || tags != nil && len(tags) < 1 {
+				break // malformed profile
+			}
+			if len(tags) < 1 {
+				break // mismatched profile records and tags
+			}
+			timestamp := data[1]
+			ppid := data[2] >> 1
+			if hasP := (data[2] & 0b1) != 0; !hasP {
+				ppid = ^uint64(0)
+			}
+			goid := data[3]
+			stk := data[4:data[0]]
+			empty := len(stk) == 1 && data[2] == 0 && data[3] == 0
+			data = data[data[0]:]
+			// No support here for reporting goroutine tags at the moment; if
+			// that information is to be part of the execution trace, we'd
+			// probably want to see when the tags are applied and when they
+			// change, instead of only seeing them when we get a CPU sample.
+			tags = tags[1:]
+
+			if empty {
+				// Looks like an overflow record from the profBuf. Not much to
+				// do here, we only want to report full records.
+				//
+				// TODO: should we start a goroutine to drain the profBuf,
+				// rather than relying on a high-enough volume of tracing events
+				// to keep ReadTrace busy? https://go.dev/issue/52674
+				continue
+			}
+
+			buf := bufp.ptr()
+			if buf == nil {
+				*bufp = traceFlush(*bufp, 0)
+				buf = bufp.ptr()
+			}
+			for i := range stk {
+				if i >= len(buf.stk) {
+					break
+				}
+				buf.stk[i] = uintptr(stk[i])
+			}
+			stackID := trace.stackTab.put(buf.stk[:len(stk)])
+
+			traceEventLocked(0, nil, 0, bufp, traceEvCPUSample, stackID, 1, timestamp/traceTickDiv, ppid, goid)
+		}
+	}
+}
+
+func traceStackID(mp *m, buf []uintptr, skip int) uint64 {
+	_g_ := getg()
+	gp := mp.curg
+	var nstk int
+	if gp == _g_ {
+		nstk = callers(skip+1, buf)
+	} else if gp != nil {
+		gp = mp.curg
+		nstk = gcallers(gp, skip, buf)
+	}
+	if nstk > 0 {
+		nstk-- // skip runtime.goexit
+	}
+	if nstk > 0 && gp.goid == 1 {
+		nstk-- // skip runtime.main
+	}
+	id := trace.stackTab.put(buf[:nstk])
+	return uint64(id)
+}
+
+// traceAcquireBuffer returns trace buffer to use and, if necessary, locks it.
+func traceAcquireBuffer() (mp *m, pid int32, bufp *traceBufPtr) {
+	mp = acquirem()
+	if p := mp.p.ptr(); p != nil {
+		return mp, p.id, &p.tracebuf
+	}
+	lock(&trace.bufLock)
+	return mp, traceGlobProc, &trace.buf
+}
+
+// traceReleaseBuffer releases a buffer previously acquired with traceAcquireBuffer.
+func traceReleaseBuffer(pid int32) {
+	if pid == traceGlobProc {
+		unlock(&trace.bufLock)
+	}
+	releasem(getg().m)
+}
+
+// traceFlush puts buf onto stack of full buffers and returns an empty buffer.
+func traceFlush(buf traceBufPtr, pid int32) traceBufPtr {
+	owner := trace.lockOwner
+	dolock := owner == nil || owner != getg().m.curg
+	if dolock {
+		lock(&trace.lock)
+	}
+	if buf != 0 {
+		traceFullQueue(buf)
+	}
+	if trace.empty != 0 {
+		buf = trace.empty
+		trace.empty = buf.ptr().link
+	} else {
+		buf = traceBufPtr(sysAlloc(unsafe.Sizeof(traceBuf{}), &memstats.other_sys))
+		if buf == 0 {
+			throw("trace: out of memory")
+		}
+	}
+	bufp := buf.ptr()
+	bufp.link.set(nil)
+	bufp.pos = 0
+
+	// initialize the buffer for a new batch
+	ticks := uint64(cputicks()) / traceTickDiv
+	if ticks == bufp.lastTicks {
+		ticks = bufp.lastTicks + 1
+	}
+	bufp.lastTicks = ticks
+	bufp.byte(traceEvBatch | 1<<traceArgCountShift)
+	bufp.varint(uint64(pid))
+	bufp.varint(ticks)
+
+	if dolock {
+		unlock(&trace.lock)
+	}
+	return buf
+}
+
+// traceString adds a string to the trace.strings and returns the id.
+func traceString(bufp *traceBufPtr, pid int32, s string) (uint64, *traceBufPtr) {
+	if s == "" {
+		return 0, bufp
+	}
+
+	lock(&trace.stringsLock)
+	if raceenabled {
+		// raceacquire is necessary because the map access
+		// below is race annotated.
+		raceacquire(unsafe.Pointer(&trace.stringsLock))
+	}
+
+	if id, ok := trace.strings[s]; ok {
+		if raceenabled {
+			racerelease(unsafe.Pointer(&trace.stringsLock))
+		}
+		unlock(&trace.stringsLock)
+
+		return id, bufp
+	}
+
+	trace.stringSeq++
+	id := trace.stringSeq
+	trace.strings[s] = id
+
+	if raceenabled {
+		racerelease(unsafe.Pointer(&trace.stringsLock))
+	}
+	unlock(&trace.stringsLock)
+
+	// memory allocation in above may trigger tracing and
+	// cause *bufp changes. Following code now works with *bufp,
+	// so there must be no memory allocation or any activities
+	// that causes tracing after this point.
+
+	buf := bufp.ptr()
+	size := 1 + 2*traceBytesPerNumber + len(s)
+	if buf == nil || len(buf.arr)-buf.pos < size {
+		buf = traceFlush(traceBufPtrOf(buf), pid).ptr()
+		bufp.set(buf)
+	}
+	buf.byte(traceEvString)
+	buf.varint(id)
+
+	// double-check the string and the length can fit.
+	// Otherwise, truncate the string.
+	slen := len(s)
+	if room := len(buf.arr) - buf.pos; room < slen+traceBytesPerNumber {
+		slen = room
+	}
+
+	buf.varint(uint64(slen))
+	buf.pos += copy(buf.arr[buf.pos:], s[:slen])
+
+	bufp.set(buf)
+	return id, bufp
+}
+
+// traceAppend appends v to buf in little-endian-base-128 encoding.
+func traceAppend(buf []byte, v uint64) []byte {
+	for ; v >= 0x80; v >>= 7 {
+		buf = append(buf, 0x80|byte(v))
+	}
+	buf = append(buf, byte(v))
+	return buf
+}
+
+// varint appends v to buf in little-endian-base-128 encoding.
+func (buf *traceBuf) varint(v uint64) {
+	pos := buf.pos
+	for ; v >= 0x80; v >>= 7 {
+		buf.arr[pos] = 0x80 | byte(v)
+		pos++
+	}
+	buf.arr[pos] = byte(v)
+	pos++
+	buf.pos = pos
+}
+
+// byte appends v to buf.
+func (buf *traceBuf) byte(v byte) {
+	buf.arr[buf.pos] = v
+	buf.pos++
+}
+
+// traceStackTable maps stack traces (arrays of PC's) to unique uint32 ids.
+// It is lock-free for reading.
+type traceStackTable struct {
+	lock mutex
+	seq  uint32
+	mem  traceAlloc
+	tab  [1 << 13]traceStackPtr
+}
+
+// traceStack is a single stack in traceStackTable.
+type traceStack struct {
+	link traceStackPtr
+	hash uintptr
+	id   uint32
+	n    int
+	stk  [0]uintptr // real type [n]uintptr
+}
+
+type traceStackPtr uintptr
+
+func (tp traceStackPtr) ptr() *traceStack { return (*traceStack)(unsafe.Pointer(tp)) }
+
+// stack returns slice of PCs.
+func (ts *traceStack) stack() []uintptr {
+	return (*[traceStackSize]uintptr)(unsafe.Pointer(&ts.stk))[:ts.n]
+}
+
+// put returns a unique id for the stack trace pcs and caches it in the table,
+// if it sees the trace for the first time.
+func (tab *traceStackTable) put(pcs []uintptr) uint32 {
+	if len(pcs) == 0 {
+		return 0
+	}
+	hash := memhash(unsafe.Pointer(&pcs[0]), 0, uintptr(len(pcs))*unsafe.Sizeof(pcs[0]))
+	// First, search the hashtable w/o the mutex.
+	if id := tab.find(pcs, hash); id != 0 {
+		return id
+	}
+	// Now, double check under the mutex.
+	lock(&tab.lock)
+	if id := tab.find(pcs, hash); id != 0 {
+		unlock(&tab.lock)
+		return id
+	}
+	// Create new record.
+	tab.seq++
+	stk := tab.newStack(len(pcs))
+	stk.hash = hash
+	stk.id = tab.seq
+	stk.n = len(pcs)
+	stkpc := stk.stack()
+	for i, pc := range pcs {
+		stkpc[i] = pc
+	}
+	part := int(hash % uintptr(len(tab.tab)))
+	stk.link = tab.tab[part]
+	atomicstorep(unsafe.Pointer(&tab.tab[part]), unsafe.Pointer(stk))
+	unlock(&tab.lock)
+	return stk.id
+}
+
+// find checks if the stack trace pcs is already present in the table.
+func (tab *traceStackTable) find(pcs []uintptr, hash uintptr) uint32 {
+	part := int(hash % uintptr(len(tab.tab)))
+Search:
+	for stk := tab.tab[part].ptr(); stk != nil; stk = stk.link.ptr() {
+		if stk.hash == hash && stk.n == len(pcs) {
+			for i, stkpc := range stk.stack() {
+				if stkpc != pcs[i] {
+					continue Search
+				}
+			}
+			return stk.id
+		}
+	}
+	return 0
+}
+
+// newStack allocates a new stack of size n.
+func (tab *traceStackTable) newStack(n int) *traceStack {
+	return (*traceStack)(tab.mem.alloc(unsafe.Sizeof(traceStack{}) + uintptr(n)*goarch.PtrSize))
+}
+
+// allFrames returns all of the Frames corresponding to pcs.
+func allFrames(pcs []uintptr) []Frame {
+	frames := make([]Frame, 0, len(pcs))
+	ci := CallersFrames(pcs)
+	for {
+		f, more := ci.Next()
+		frames = append(frames, f)
+		if !more {
+			return frames
+		}
+	}
+}
+
+// dump writes all previously cached stacks to trace buffers,
+// releases all memory and resets state.
+func (tab *traceStackTable) dump() {
+	var tmp [(2 + 4*traceStackSize) * traceBytesPerNumber]byte
+	bufp := traceFlush(0, 0)
+	for _, stk := range tab.tab {
+		stk := stk.ptr()
+		for ; stk != nil; stk = stk.link.ptr() {
+			tmpbuf := tmp[:0]
+			tmpbuf = traceAppend(tmpbuf, uint64(stk.id))
+			frames := allFrames(stk.stack())
+			tmpbuf = traceAppend(tmpbuf, uint64(len(frames)))
+			for _, f := range frames {
+				var frame traceFrame
+				frame, bufp = traceFrameForPC(bufp, 0, f)
+				tmpbuf = traceAppend(tmpbuf, uint64(f.PC))
+				tmpbuf = traceAppend(tmpbuf, uint64(frame.funcID))
+				tmpbuf = traceAppend(tmpbuf, uint64(frame.fileID))
+				tmpbuf = traceAppend(tmpbuf, uint64(frame.line))
+			}
+			// Now copy to the buffer.
+			size := 1 + traceBytesPerNumber + len(tmpbuf)
+			if buf := bufp.ptr(); len(buf.arr)-buf.pos < size {
+				bufp = traceFlush(bufp, 0)
+			}
+			buf := bufp.ptr()
+			buf.byte(traceEvStack | 3<<traceArgCountShift)
+			buf.varint(uint64(len(tmpbuf)))
+			buf.pos += copy(buf.arr[buf.pos:], tmpbuf)
+		}
+	}
+
+	lock(&trace.lock)
+	traceFullQueue(bufp)
+	unlock(&trace.lock)
+
+	tab.mem.drop()
+	*tab = traceStackTable{}
+	lockInit(&((*tab).lock), lockRankTraceStackTab)
+}
+
+type traceFrame struct {
+	funcID uint64
+	fileID uint64
+	line   uint64
+}
+
+// traceFrameForPC records the frame information.
+// It may allocate memory.
+func traceFrameForPC(buf traceBufPtr, pid int32, f Frame) (traceFrame, traceBufPtr) {
+	bufp := &buf
+	var frame traceFrame
+
+	fn := f.Function
+	const maxLen = 1 << 10
+	if len(fn) > maxLen {
+		fn = fn[len(fn)-maxLen:]
+	}
+	frame.funcID, bufp = traceString(bufp, pid, fn)
+	frame.line = uint64(f.Line)
+	file := f.File
+	if len(file) > maxLen {
+		file = file[len(file)-maxLen:]
+	}
+	frame.fileID, bufp = traceString(bufp, pid, file)
+	return frame, (*bufp)
+}
+
+// traceAlloc is a non-thread-safe region allocator.
+// It holds a linked list of traceAllocBlock.
+type traceAlloc struct {
+	head traceAllocBlockPtr
+	off  uintptr
+}
+
+// traceAllocBlock is a block in traceAlloc.
+//
+// traceAllocBlock is allocated from non-GC'd memory, so it must not
+// contain heap pointers. Writes to pointers to traceAllocBlocks do
+// not need write barriers.
+//
+//go:notinheap
+type traceAllocBlock struct {
+	next traceAllocBlockPtr
+	data [64<<10 - goarch.PtrSize]byte
+}
+
+// TODO: Since traceAllocBlock is now go:notinheap, this isn't necessary.
+type traceAllocBlockPtr uintptr
+
+func (p traceAllocBlockPtr) ptr() *traceAllocBlock   { return (*traceAllocBlock)(unsafe.Pointer(p)) }
+func (p *traceAllocBlockPtr) set(x *traceAllocBlock) { *p = traceAllocBlockPtr(unsafe.Pointer(x)) }
+
+// alloc allocates n-byte block.
+func (a *traceAlloc) alloc(n uintptr) unsafe.Pointer {
+	n = alignUp(n, goarch.PtrSize)
+	if a.head == 0 || a.off+n > uintptr(len(a.head.ptr().data)) {
+		if n > uintptr(len(a.head.ptr().data)) {
+			throw("trace: alloc too large")
+		}
+		block := (*traceAllocBlock)(sysAlloc(unsafe.Sizeof(traceAllocBlock{}), &memstats.other_sys))
+		if block == nil {
+			throw("trace: out of memory")
+		}
+		block.next.set(a.head.ptr())
+		a.head.set(block)
+		a.off = 0
+	}
+	p := &a.head.ptr().data[a.off]
+	a.off += n
+	return unsafe.Pointer(p)
+}
+
+// drop frees all previously allocated memory and resets the allocator.
+func (a *traceAlloc) drop() {
+	for a.head != 0 {
+		block := a.head.ptr()
+		a.head.set(block.next.ptr())
+		sysFree(unsafe.Pointer(block), unsafe.Sizeof(traceAllocBlock{}), &memstats.other_sys)
+	}
+}
+
+// The following functions write specific events to trace.
+
+func traceGomaxprocs(procs int32) {
+	traceEvent(traceEvGomaxprocs, 1, uint64(procs))
+}
+
+func traceProcStart() {
+	traceEvent(traceEvProcStart, -1, uint64(getg().m.id))
+}
+
+func traceProcStop(pp *p) {
+	// Sysmon and stopTheWorld can stop Ps blocked in syscalls,
+	// to handle this we temporary employ the P.
+	mp := acquirem()
+	oldp := mp.p
+	mp.p.set(pp)
+	traceEvent(traceEvProcStop, -1)
+	mp.p = oldp
+	releasem(mp)
+}
+
+func traceGCStart() {
+	traceEvent(traceEvGCStart, 3, trace.seqGC)
+	trace.seqGC++
+}
+
+func traceGCDone() {
+	traceEvent(traceEvGCDone, -1)
+}
+
+func traceGCSTWStart(kind int) {
+	traceEvent(traceEvGCSTWStart, -1, uint64(kind))
+}
+
+func traceGCSTWDone() {
+	traceEvent(traceEvGCSTWDone, -1)
+}
+
+// traceGCSweepStart prepares to trace a sweep loop. This does not
+// emit any events until traceGCSweepSpan is called.
+//
+// traceGCSweepStart must be paired with traceGCSweepDone and there
+// must be no preemption points between these two calls.
+func traceGCSweepStart() {
+	// Delay the actual GCSweepStart event until the first span
+	// sweep. If we don't sweep anything, don't emit any events.
+	_p_ := getg().m.p.ptr()
+	if _p_.traceSweep {
+		throw("double traceGCSweepStart")
+	}
+	_p_.traceSweep, _p_.traceSwept, _p_.traceReclaimed = true, 0, 0
+}
+
+// traceGCSweepSpan traces the sweep of a single page.
+//
+// This may be called outside a traceGCSweepStart/traceGCSweepDone
+// pair; however, it will not emit any trace events in this case.
+func traceGCSweepSpan(bytesSwept uintptr) {
+	_p_ := getg().m.p.ptr()
+	if _p_.traceSweep {
+		if _p_.traceSwept == 0 {
+			traceEvent(traceEvGCSweepStart, 1)
+		}
+		_p_.traceSwept += bytesSwept
+	}
+}
+
+func traceGCSweepDone() {
+	_p_ := getg().m.p.ptr()
+	if !_p_.traceSweep {
+		throw("missing traceGCSweepStart")
+	}
+	if _p_.traceSwept != 0 {
+		traceEvent(traceEvGCSweepDone, -1, uint64(_p_.traceSwept), uint64(_p_.traceReclaimed))
+	}
+	_p_.traceSweep = false
+}
+
+func traceGCMarkAssistStart() {
+	traceEvent(traceEvGCMarkAssistStart, 1)
+}
+
+func traceGCMarkAssistDone() {
+	traceEvent(traceEvGCMarkAssistDone, -1)
+}
+
+func traceGoCreate(newg *g, pc uintptr) {
+	newg.traceseq = 0
+	newg.tracelastp = getg().m.p
+	// +PCQuantum because traceFrameForPC expects return PCs and subtracts PCQuantum.
+	id := trace.stackTab.put([]uintptr{startPCforTrace(pc) + sys.PCQuantum})
+	traceEvent(traceEvGoCreate, 2, uint64(newg.goid), uint64(id))
+}
+
+func traceGoStart() {
+	_g_ := getg().m.curg
+	_p_ := _g_.m.p
+	_g_.traceseq++
+	if _p_.ptr().gcMarkWorkerMode != gcMarkWorkerNotWorker {
+		traceEvent(traceEvGoStartLabel, -1, uint64(_g_.goid), _g_.traceseq, trace.markWorkerLabels[_p_.ptr().gcMarkWorkerMode])
+	} else if _g_.tracelastp == _p_ {
+		traceEvent(traceEvGoStartLocal, -1, uint64(_g_.goid))
+	} else {
+		_g_.tracelastp = _p_
+		traceEvent(traceEvGoStart, -1, uint64(_g_.goid), _g_.traceseq)
+	}
+}
+
+func traceGoEnd() {
+	traceEvent(traceEvGoEnd, -1)
+}
+
+func traceGoSched() {
+	_g_ := getg()
+	_g_.tracelastp = _g_.m.p
+	traceEvent(traceEvGoSched, 1)
+}
+
+func traceGoPreempt() {
+	_g_ := getg()
+	_g_.tracelastp = _g_.m.p
+	traceEvent(traceEvGoPreempt, 1)
+}
+
+func traceGoPark(traceEv byte, skip int) {
+	if traceEv&traceFutileWakeup != 0 {
+		traceEvent(traceEvFutileWakeup, -1)
+	}
+	traceEvent(traceEv & ^traceFutileWakeup, skip)
+}
+
+func traceGoUnpark(gp *g, skip int) {
+	_p_ := getg().m.p
+	gp.traceseq++
+	if gp.tracelastp == _p_ {
+		traceEvent(traceEvGoUnblockLocal, skip, uint64(gp.goid))
+	} else {
+		gp.tracelastp = _p_
+		traceEvent(traceEvGoUnblock, skip, uint64(gp.goid), gp.traceseq)
+	}
+}
+
+func traceGoSysCall() {
+	traceEvent(traceEvGoSysCall, 1)
+}
+
+func traceGoSysExit(ts int64) {
+	if ts != 0 && ts < trace.ticksStart {
+		// There is a race between the code that initializes sysexitticks
+		// (in exitsyscall, which runs without a P, and therefore is not
+		// stopped with the rest of the world) and the code that initializes
+		// a new trace. The recorded sysexitticks must therefore be treated
+		// as "best effort". If they are valid for this trace, then great,
+		// use them for greater accuracy. But if they're not valid for this
+		// trace, assume that the trace was started after the actual syscall
+		// exit (but before we actually managed to start the goroutine,
+		// aka right now), and assign a fresh time stamp to keep the log consistent.
+		ts = 0
+	}
+	_g_ := getg().m.curg
+	_g_.traceseq++
+	_g_.tracelastp = _g_.m.p
+	traceEvent(traceEvGoSysExit, -1, uint64(_g_.goid), _g_.traceseq, uint64(ts)/traceTickDiv)
+}
+
+func traceGoSysBlock(pp *p) {
+	// Sysmon and stopTheWorld can declare syscalls running on remote Ps as blocked,
+	// to handle this we temporary employ the P.
+	mp := acquirem()
+	oldp := mp.p
+	mp.p.set(pp)
+	traceEvent(traceEvGoSysBlock, -1)
+	mp.p = oldp
+	releasem(mp)
+}
+
+func traceHeapAlloc() {
+	traceEvent(traceEvHeapAlloc, -1, gcController.heapLive)
+}
+
+func traceHeapGoal() {
+	heapGoal := gcController.heapGoal()
+	if heapGoal == ^uint64(0) {
+		// Heap-based triggering is disabled.
+		traceEvent(traceEvHeapGoal, -1, 0)
+	} else {
+		traceEvent(traceEvHeapGoal, -1, heapGoal)
+	}
+}
+
+// To access runtime functions from runtime/trace.
+// See runtime/trace/annotation.go
+
+//go:linkname trace_userTaskCreate runtime/trace.userTaskCreate
+func trace_userTaskCreate(id, parentID uint64, taskType string) {
+	if !trace.enabled {
+		return
+	}
+
+	// Same as in traceEvent.
+	mp, pid, bufp := traceAcquireBuffer()
+	if !trace.enabled && !mp.startingtrace {
+		traceReleaseBuffer(pid)
+		return
+	}
+
+	typeStringID, bufp := traceString(bufp, pid, taskType)
+	traceEventLocked(0, mp, pid, bufp, traceEvUserTaskCreate, 0, 3, id, parentID, typeStringID)
+	traceReleaseBuffer(pid)
+}
+
+//go:linkname trace_userTaskEnd runtime/trace.userTaskEnd
+func trace_userTaskEnd(id uint64) {
+	traceEvent(traceEvUserTaskEnd, 2, id)
+}
+
+//go:linkname trace_userRegion runtime/trace.userRegion
+func trace_userRegion(id, mode uint64, name string) {
+	if !trace.enabled {
+		return
+	}
+
+	mp, pid, bufp := traceAcquireBuffer()
+	if !trace.enabled && !mp.startingtrace {
+		traceReleaseBuffer(pid)
+		return
+	}
+
+	nameStringID, bufp := traceString(bufp, pid, name)
+	traceEventLocked(0, mp, pid, bufp, traceEvUserRegion, 0, 3, id, mode, nameStringID)
+	traceReleaseBuffer(pid)
+}
+
+//go:linkname trace_userLog runtime/trace.userLog
+func trace_userLog(id uint64, category, message string) {
+	if !trace.enabled {
+		return
+	}
+
+	mp, pid, bufp := traceAcquireBuffer()
+	if !trace.enabled && !mp.startingtrace {
+		traceReleaseBuffer(pid)
+		return
+	}
+
+	categoryID, bufp := traceString(bufp, pid, category)
+
+	extraSpace := traceBytesPerNumber + len(message) // extraSpace for the value string
+	traceEventLocked(extraSpace, mp, pid, bufp, traceEvUserLog, 0, 3, id, categoryID)
+	// traceEventLocked reserved extra space for val and len(val)
+	// in buf, so buf now has room for the following.
+	buf := bufp.ptr()
+
+	// double-check the message and its length can fit.
+	// Otherwise, truncate the message.
+	slen := len(message)
+	if room := len(buf.arr) - buf.pos; room < slen+traceBytesPerNumber {
+		slen = room
+	}
+	buf.varint(uint64(slen))
+	buf.pos += copy(buf.arr[buf.pos:], message[:slen])
+
+	traceReleaseBuffer(pid)
+}
+
+// the start PC of a goroutine for tracing purposes. If pc is a wrapper,
+// it returns the PC of the wrapped function. Otherwise it returns pc.
+func startPCforTrace(pc uintptr) uintptr {
+	f := findfunc(pc)
+	if !f.valid() {
+		return pc // should not happen, but don't care
+	}
+	w := funcdata(f, _FUNCDATA_WrapInfo)
+	if w == nil {
+		return pc // not a wrapper
+	}
+	return f.datap.textAddr(*(*uint32)(w))
+}
diff --git a/contrib/go/_std_1.19/src/runtime/traceback.go b/contrib/go/_std_1.19/src/runtime/traceback.go
new file mode 100644
index 0000000000..49147ff838
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/traceback.go
@@ -0,0 +1,1447 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"internal/bytealg"
+	"internal/goarch"
+	"runtime/internal/atomic"
+	"runtime/internal/sys"
+	"unsafe"
+)
+
+// The code in this file implements stack trace walking for all architectures.
+// The most important fact about a given architecture is whether it uses a link register.
+// On systems with link registers, the prologue for a non-leaf function stores the
+// incoming value of LR at the bottom of the newly allocated stack frame.
+// On systems without link registers (x86), the architecture pushes a return PC during
+// the call instruction, so the return PC ends up above the stack frame.
+// In this file, the return PC is always called LR, no matter how it was found.
+
+const usesLR = sys.MinFrameSize > 0
+
+// Generic traceback. Handles runtime stack prints (pcbuf == nil),
+// the runtime.Callers function (pcbuf != nil), as well as the garbage
+// collector (callback != nil).  A little clunky to merge these, but avoids
+// duplicating the code and all its subtlety.
+//
+// The skip argument is only valid with pcbuf != nil and counts the number
+// of logical frames to skip rather than physical frames (with inlining, a
+// PC in pcbuf can represent multiple calls).
+func gentraceback(pc0, sp0, lr0 uintptr, gp *g, skip int, pcbuf *uintptr, max int, callback func(*stkframe, unsafe.Pointer) bool, v unsafe.Pointer, flags uint) int {
+	if skip > 0 && callback != nil {
+		throw("gentraceback callback cannot be used with non-zero skip")
+	}
+
+	// Don't call this "g"; it's too easy get "g" and "gp" confused.
+	if ourg := getg(); ourg == gp && ourg == ourg.m.curg {
+		// The starting sp has been passed in as a uintptr, and the caller may
+		// have other uintptr-typed stack references as well.
+		// If during one of the calls that got us here or during one of the
+		// callbacks below the stack must be grown, all these uintptr references
+		// to the stack will not be updated, and gentraceback will continue
+		// to inspect the old stack memory, which may no longer be valid.
+		// Even if all the variables were updated correctly, it is not clear that
+		// we want to expose a traceback that begins on one stack and ends
+		// on another stack. That could confuse callers quite a bit.
+		// Instead, we require that gentraceback and any other function that
+		// accepts an sp for the current goroutine (typically obtained by
+		// calling getcallersp) must not run on that goroutine's stack but
+		// instead on the g0 stack.
+		throw("gentraceback cannot trace user goroutine on its own stack")
+	}
+	level, _, _ := gotraceback()
+
+	var ctxt *funcval // Context pointer for unstarted goroutines. See issue #25897.
+
+	if pc0 == ^uintptr(0) && sp0 == ^uintptr(0) { // Signal to fetch saved values from gp.
+		if gp.syscallsp != 0 {
+			pc0 = gp.syscallpc
+			sp0 = gp.syscallsp
+			if usesLR {
+				lr0 = 0
+			}
+		} else {
+			pc0 = gp.sched.pc
+			sp0 = gp.sched.sp
+			if usesLR {
+				lr0 = gp.sched.lr
+			}
+			ctxt = (*funcval)(gp.sched.ctxt)
+		}
+	}
+
+	nprint := 0
+	var frame stkframe
+	frame.pc = pc0
+	frame.sp = sp0
+	if usesLR {
+		frame.lr = lr0
+	}
+	waspanic := false
+	cgoCtxt := gp.cgoCtxt
+	stack := gp.stack
+	printing := pcbuf == nil && callback == nil
+
+	// If the PC is zero, it's likely a nil function call.
+	// Start in the caller's frame.
+	if frame.pc == 0 {
+		if usesLR {
+			frame.pc = *(*uintptr)(unsafe.Pointer(frame.sp))
+			frame.lr = 0
+		} else {
+			frame.pc = uintptr(*(*uintptr)(unsafe.Pointer(frame.sp)))
+			frame.sp += goarch.PtrSize
+		}
+	}
+
+	// runtime/internal/atomic functions call into kernel helpers on
+	// arm < 7. See runtime/internal/atomic/sys_linux_arm.s.
+	//
+	// Start in the caller's frame.
+	if GOARCH == "arm" && goarm < 7 && GOOS == "linux" && frame.pc&0xffff0000 == 0xffff0000 {
+		// Note that the calls are simple BL without pushing the return
+		// address, so we use LR directly.
+		//
+		// The kernel helpers are frameless leaf functions, so SP and
+		// LR are not touched.
+		frame.pc = frame.lr
+		frame.lr = 0
+	}
+
+	f := findfunc(frame.pc)
+	if !f.valid() {
+		if callback != nil || printing {
+			print("runtime: g ", gp.goid, ": unknown pc ", hex(frame.pc), "\n")
+			tracebackHexdump(stack, &frame, 0)
+		}
+		if callback != nil {
+			throw("unknown pc")
+		}
+		return 0
+	}
+	frame.fn = f
+
+	var cache pcvalueCache
+
+	lastFuncID := funcID_normal
+	n := 0
+	for n < max {
+		// Typically:
+		//	pc is the PC of the running function.
+		//	sp is the stack pointer at that program counter.
+		//	fp is the frame pointer (caller's stack pointer) at that program counter, or nil if unknown.
+		//	stk is the stack containing sp.
+		//	The caller's program counter is lr, unless lr is zero, in which case it is *(uintptr*)sp.
+		f = frame.fn
+		if f.pcsp == 0 {
+			// No frame information, must be external function, like race support.
+			// See golang.org/issue/13568.
+			break
+		}
+
+		// Compute function info flags.
+		flag := f.flag
+		if f.funcID == funcID_cgocallback {
+			// cgocallback does write SP to switch from the g0 to the curg stack,
+			// but it carefully arranges that during the transition BOTH stacks
+			// have cgocallback frame valid for unwinding through.
+			// So we don't need to exclude it with the other SP-writing functions.
+			flag &^= funcFlag_SPWRITE
+		}
+		if frame.pc == pc0 && frame.sp == sp0 && pc0 == gp.syscallpc && sp0 == gp.syscallsp {
+			// Some Syscall functions write to SP, but they do so only after
+			// saving the entry PC/SP using entersyscall.
+			// Since we are using the entry PC/SP, the later SP write doesn't matter.
+			flag &^= funcFlag_SPWRITE
+		}
+
+		// Found an actual function.
+		// Derive frame pointer and link register.
+		if frame.fp == 0 {
+			// Jump over system stack transitions. If we're on g0 and there's a user
+			// goroutine, try to jump. Otherwise this is a regular call.
+			if flags&_TraceJumpStack != 0 && gp == gp.m.g0 && gp.m.curg != nil {
+				switch f.funcID {
+				case funcID_morestack:
+					// morestack does not return normally -- newstack()
+					// gogo's to curg.sched. Match that.
+					// This keeps morestack() from showing up in the backtrace,
+					// but that makes some sense since it'll never be returned
+					// to.
+					frame.pc = gp.m.curg.sched.pc
+					frame.fn = findfunc(frame.pc)
+					f = frame.fn
+					flag = f.flag
+					frame.lr = gp.m.curg.sched.lr
+					frame.sp = gp.m.curg.sched.sp
+					stack = gp.m.curg.stack
+					cgoCtxt = gp.m.curg.cgoCtxt
+				case funcID_systemstack:
+					// systemstack returns normally, so just follow the
+					// stack transition.
+					frame.sp = gp.m.curg.sched.sp
+					stack = gp.m.curg.stack
+					cgoCtxt = gp.m.curg.cgoCtxt
+					flag &^= funcFlag_SPWRITE
+				}
+			}
+			frame.fp = frame.sp + uintptr(funcspdelta(f, frame.pc, &cache))
+			if !usesLR {
+				// On x86, call instruction pushes return PC before entering new function.
+				frame.fp += goarch.PtrSize
+			}
+		}
+		var flr funcInfo
+		if flag&funcFlag_TOPFRAME != 0 {
+			// This function marks the top of the stack. Stop the traceback.
+			frame.lr = 0
+			flr = funcInfo{}
+		} else if flag&funcFlag_SPWRITE != 0 && (callback == nil || n > 0) {
+			// The function we are in does a write to SP that we don't know
+			// how to encode in the spdelta table. Examples include context
+			// switch routines like runtime.gogo but also any code that switches
+			// to the g0 stack to run host C code. Since we can't reliably unwind
+			// the SP (we might not even be on the stack we think we are),
+			// we stop the traceback here.
+			// This only applies for profiling signals (callback == nil).
+			//
+			// For a GC stack traversal (callback != nil), we should only see
+			// a function when it has voluntarily preempted itself on entry
+			// during the stack growth check. In that case, the function has
+			// not yet had a chance to do any writes to SP and is safe to unwind.
+			// isAsyncSafePoint does not allow assembly functions to be async preempted,
+			// and preemptPark double-checks that SPWRITE functions are not async preempted.
+			// So for GC stack traversal we leave things alone (this if body does not execute for n == 0)
+			// at the bottom frame of the stack. But farther up the stack we'd better not
+			// find any.
+			if callback != nil {
+				println("traceback: unexpected SPWRITE function", funcname(f))
+				throw("traceback")
+			}
+			frame.lr = 0
+			flr = funcInfo{}
+		} else {
+			var lrPtr uintptr
+			if usesLR {
+				if n == 0 && frame.sp < frame.fp || frame.lr == 0 {
+					lrPtr = frame.sp
+					frame.lr = *(*uintptr)(unsafe.Pointer(lrPtr))
+				}
+			} else {
+				if frame.lr == 0 {
+					lrPtr = frame.fp - goarch.PtrSize
+					frame.lr = uintptr(*(*uintptr)(unsafe.Pointer(lrPtr)))
+				}
+			}
+			flr = findfunc(frame.lr)
+			if !flr.valid() {
+				// This happens if you get a profiling interrupt at just the wrong time.
+				// In that context it is okay to stop early.
+				// But if callback is set, we're doing a garbage collection and must
+				// get everything, so crash loudly.
+				doPrint := printing
+				if doPrint && gp.m.incgo && f.funcID == funcID_sigpanic {
+					// We can inject sigpanic
+					// calls directly into C code,
+					// in which case we'll see a C
+					// return PC. Don't complain.
+					doPrint = false
+				}
+				if callback != nil || doPrint {
+					print("runtime: g ", gp.goid, ": unexpected return pc for ", funcname(f), " called from ", hex(frame.lr), "\n")
+					tracebackHexdump(stack, &frame, lrPtr)
+				}
+				if callback != nil {
+					throw("unknown caller pc")
+				}
+			}
+		}
+
+		frame.varp = frame.fp
+		if !usesLR {
+			// On x86, call instruction pushes return PC before entering new function.
+			frame.varp -= goarch.PtrSize
+		}
+
+		// For architectures with frame pointers, if there's
+		// a frame, then there's a saved frame pointer here.
+		//
+		// NOTE: This code is not as general as it looks.
+		// On x86, the ABI is to save the frame pointer word at the
+		// top of the stack frame, so we have to back down over it.
+		// On arm64, the frame pointer should be at the bottom of
+		// the stack (with R29 (aka FP) = RSP), in which case we would
+		// not want to do the subtraction here. But we started out without
+		// any frame pointer, and when we wanted to add it, we didn't
+		// want to break all the assembly doing direct writes to 8(RSP)
+		// to set the first parameter to a called function.
+		// So we decided to write the FP link *below* the stack pointer
+		// (with R29 = RSP - 8 in Go functions).
+		// This is technically ABI-compatible but not standard.
+		// And it happens to end up mimicking the x86 layout.
+		// Other architectures may make different decisions.
+		if frame.varp > frame.sp && framepointer_enabled {
+			frame.varp -= goarch.PtrSize
+		}
+
+		// Derive size of arguments.
+		// Most functions have a fixed-size argument block,
+		// so we can use metadata about the function f.
+		// Not all, though: there are some variadic functions
+		// in package runtime and reflect, and for those we use call-specific
+		// metadata recorded by f's caller.
+		if callback != nil || printing {
+			frame.argp = frame.fp + sys.MinFrameSize
+			var ok bool
+			frame.arglen, frame.argmap, ok = getArgInfoFast(f, callback != nil)
+			if !ok {
+				frame.arglen, frame.argmap = getArgInfo(&frame, f, callback != nil, ctxt)
+			}
+		}
+		ctxt = nil // ctxt is only needed to get arg maps for the topmost frame
+
+		// Determine frame's 'continuation PC', where it can continue.
+		// Normally this is the return address on the stack, but if sigpanic
+		// is immediately below this function on the stack, then the frame
+		// stopped executing due to a trap, and frame.pc is probably not
+		// a safe point for looking up liveness information. In this panicking case,
+		// the function either doesn't return at all (if it has no defers or if the
+		// defers do not recover) or it returns from one of the calls to
+		// deferproc a second time (if the corresponding deferred func recovers).
+		// In the latter case, use a deferreturn call site as the continuation pc.
+		frame.continpc = frame.pc
+		if waspanic {
+			if frame.fn.deferreturn != 0 {
+				frame.continpc = frame.fn.entry() + uintptr(frame.fn.deferreturn) + 1
+				// Note: this may perhaps keep return variables alive longer than
+				// strictly necessary, as we are using "function has a defer statement"
+				// as a proxy for "function actually deferred something". It seems
+				// to be a minor drawback. (We used to actually look through the
+				// gp._defer for a defer corresponding to this function, but that
+				// is hard to do with defer records on the stack during a stack copy.)
+				// Note: the +1 is to offset the -1 that
+				// stack.go:getStackMap does to back up a return
+				// address make sure the pc is in the CALL instruction.
+			} else {
+				frame.continpc = 0
+			}
+		}
+
+		if callback != nil {
+			if !callback((*stkframe)(noescape(unsafe.Pointer(&frame))), v) {
+				return n
+			}
+		}
+
+		if pcbuf != nil {
+			pc := frame.pc
+			// backup to CALL instruction to read inlining info (same logic as below)
+			tracepc := pc
+			// Normally, pc is a return address. In that case, we want to look up
+			// file/line information using pc-1, because that is the pc of the
+			// call instruction (more precisely, the last byte of the call instruction).
+			// Callers expect the pc buffer to contain return addresses and do the
+			// same -1 themselves, so we keep pc unchanged.
+			// When the pc is from a signal (e.g. profiler or segv) then we want
+			// to look up file/line information using pc, and we store pc+1 in the
+			// pc buffer so callers can unconditionally subtract 1 before looking up.
+			// See issue 34123.
+			// The pc can be at function entry when the frame is initialized without
+			// actually running code, like runtime.mstart.
+			if (n == 0 && flags&_TraceTrap != 0) || waspanic || pc == f.entry() {
+				pc++
+			} else {
+				tracepc--
+			}
+
+			// If there is inlining info, record the inner frames.
+			if inldata := funcdata(f, _FUNCDATA_InlTree); inldata != nil {
+				inltree := (*[1 << 20]inlinedCall)(inldata)
+				for {
+					ix := pcdatavalue(f, _PCDATA_InlTreeIndex, tracepc, &cache)
+					if ix < 0 {
+						break
+					}
+					if inltree[ix].funcID == funcID_wrapper && elideWrapperCalling(lastFuncID) {
+						// ignore wrappers
+					} else if skip > 0 {
+						skip--
+					} else if n < max {
+						(*[1 << 20]uintptr)(unsafe.Pointer(pcbuf))[n] = pc
+						n++
+					}
+					lastFuncID = inltree[ix].funcID
+					// Back up to an instruction in the "caller".
+					tracepc = frame.fn.entry() + uintptr(inltree[ix].parentPc)
+					pc = tracepc + 1
+				}
+			}
+			// Record the main frame.
+			if f.funcID == funcID_wrapper && elideWrapperCalling(lastFuncID) {
+				// Ignore wrapper functions (except when they trigger panics).
+			} else if skip > 0 {
+				skip--
+			} else if n < max {
+				(*[1 << 20]uintptr)(unsafe.Pointer(pcbuf))[n] = pc
+				n++
+			}
+			lastFuncID = f.funcID
+			n-- // offset n++ below
+		}
+
+		if printing {
+			// assume skip=0 for printing.
+			//
+			// Never elide wrappers if we haven't printed
+			// any frames. And don't elide wrappers that
+			// called panic rather than the wrapped
+			// function. Otherwise, leave them out.
+
+			// backup to CALL instruction to read inlining info (same logic as below)
+			tracepc := frame.pc
+			if (n > 0 || flags&_TraceTrap == 0) && frame.pc > f.entry() && !waspanic {
+				tracepc--
+			}
+			// If there is inlining info, print the inner frames.
+			if inldata := funcdata(f, _FUNCDATA_InlTree); inldata != nil {
+				inltree := (*[1 << 20]inlinedCall)(inldata)
+				var inlFunc _func
+				inlFuncInfo := funcInfo{&inlFunc, f.datap}
+				for {
+					ix := pcdatavalue(f, _PCDATA_InlTreeIndex, tracepc, nil)
+					if ix < 0 {
+						break
+					}
+
+					// Create a fake _func for the
+					// inlined function.
+					inlFunc.nameoff = inltree[ix].func_
+					inlFunc.funcID = inltree[ix].funcID
+
+					if (flags&_TraceRuntimeFrames) != 0 || showframe(inlFuncInfo, gp, nprint == 0, inlFuncInfo.funcID, lastFuncID) {
+						name := funcname(inlFuncInfo)
+						file, line := funcline(f, tracepc)
+						print(name, "(...)\n")
+						print("\t", file, ":", line, "\n")
+						nprint++
+					}
+					lastFuncID = inltree[ix].funcID
+					// Back up to an instruction in the "caller".
+					tracepc = frame.fn.entry() + uintptr(inltree[ix].parentPc)
+				}
+			}
+			if (flags&_TraceRuntimeFrames) != 0 || showframe(f, gp, nprint == 0, f.funcID, lastFuncID) {
+				// Print during crash.
+				//	main(0x1, 0x2, 0x3)
+				//		/home/rsc/go/src/runtime/x.go:23 +0xf
+				//
+				name := funcname(f)
+				file, line := funcline(f, tracepc)
+				if name == "runtime.gopanic" {
+					name = "panic"
+				}
+				print(name, "(")
+				argp := unsafe.Pointer(frame.argp)
+				printArgs(f, argp, tracepc)
+				print(")\n")
+				print("\t", file, ":", line)
+				if frame.pc > f.entry() {
+					print(" +", hex(frame.pc-f.entry()))
+				}
+				if gp.m != nil && gp.m.throwing >= throwTypeRuntime && gp == gp.m.curg || level >= 2 {
+					print(" fp=", hex(frame.fp), " sp=", hex(frame.sp), " pc=", hex(frame.pc))
+				}
+				print("\n")
+				nprint++
+			}
+			lastFuncID = f.funcID
+		}
+		n++
+
+		if f.funcID == funcID_cgocallback && len(cgoCtxt) > 0 {
+			ctxt := cgoCtxt[len(cgoCtxt)-1]
+			cgoCtxt = cgoCtxt[:len(cgoCtxt)-1]
+
+			// skip only applies to Go frames.
+			// callback != nil only used when we only care
+			// about Go frames.
+			if skip == 0 && callback == nil {
+				n = tracebackCgoContext(pcbuf, printing, ctxt, n, max)
+			}
+		}
+
+		waspanic = f.funcID == funcID_sigpanic
+		injectedCall := waspanic || f.funcID == funcID_asyncPreempt || f.funcID == funcID_debugCallV2
+
+		// Do not unwind past the bottom of the stack.
+		if !flr.valid() {
+			break
+		}
+
+		if frame.pc == frame.lr && frame.sp == frame.fp {
+			// If the next frame is identical to the current frame, we cannot make progress.
+			print("runtime: traceback stuck. pc=", hex(frame.pc), " sp=", hex(frame.sp), "\n")
+			tracebackHexdump(stack, &frame, frame.sp)
+			throw("traceback stuck")
+		}
+
+		// Unwind to next frame.
+		frame.fn = flr
+		frame.pc = frame.lr
+		frame.lr = 0
+		frame.sp = frame.fp
+		frame.fp = 0
+		frame.argmap = nil
+
+		// On link register architectures, sighandler saves the LR on stack
+		// before faking a call.
+		if usesLR && injectedCall {
+			x := *(*uintptr)(unsafe.Pointer(frame.sp))
+			frame.sp += alignUp(sys.MinFrameSize, sys.StackAlign)
+			f = findfunc(frame.pc)
+			frame.fn = f
+			if !f.valid() {
+				frame.pc = x
+			} else if funcspdelta(f, frame.pc, &cache) == 0 {
+				frame.lr = x
+			}
+		}
+	}
+
+	if printing {
+		n = nprint
+	}
+
+	// Note that panic != nil is okay here: there can be leftover panics,
+	// because the defers on the panic stack do not nest in frame order as
+	// they do on the defer stack. If you have:
+	//
+	//	frame 1 defers d1
+	//	frame 2 defers d2
+	//	frame 3 defers d3
+	//	frame 4 panics
+	//	frame 4's panic starts running defers
+	//	frame 5, running d3, defers d4
+	//	frame 5 panics
+	//	frame 5's panic starts running defers
+	//	frame 6, running d4, garbage collects
+	//	frame 6, running d2, garbage collects
+	//
+	// During the execution of d4, the panic stack is d4 -> d3, which
+	// is nested properly, and we'll treat frame 3 as resumable, because we
+	// can find d3. (And in fact frame 3 is resumable. If d4 recovers
+	// and frame 5 continues running, d3, d3 can recover and we'll
+	// resume execution in (returning from) frame 3.)
+	//
+	// During the execution of d2, however, the panic stack is d2 -> d3,
+	// which is inverted. The scan will match d2 to frame 2 but having
+	// d2 on the stack until then means it will not match d3 to frame 3.
+	// This is okay: if we're running d2, then all the defers after d2 have
+	// completed and their corresponding frames are dead. Not finding d3
+	// for frame 3 means we'll set frame 3's continpc == 0, which is correct
+	// (frame 3 is dead). At the end of the walk the panic stack can thus
+	// contain defers (d3 in this case) for dead frames. The inversion here
+	// always indicates a dead frame, and the effect of the inversion on the
+	// scan is to hide those dead frames, so the scan is still okay:
+	// what's left on the panic stack are exactly (and only) the dead frames.
+	//
+	// We require callback != nil here because only when callback != nil
+	// do we know that gentraceback is being called in a "must be correct"
+	// context as opposed to a "best effort" context. The tracebacks with
+	// callbacks only happen when everything is stopped nicely.
+	// At other times, such as when gathering a stack for a profiling signal
+	// or when printing a traceback during a crash, everything may not be
+	// stopped nicely, and the stack walk may not be able to complete.
+	if callback != nil && n < max && frame.sp != gp.stktopsp {
+		print("runtime: g", gp.goid, ": frame.sp=", hex(frame.sp), " top=", hex(gp.stktopsp), "\n")
+		print("\tstack=[", hex(gp.stack.lo), "-", hex(gp.stack.hi), "] n=", n, " max=", max, "\n")
+		throw("traceback did not unwind completely")
+	}
+
+	return n
+}
+
+// printArgs prints function arguments in traceback.
+func printArgs(f funcInfo, argp unsafe.Pointer, pc uintptr) {
+	// The "instruction" of argument printing is encoded in _FUNCDATA_ArgInfo.
+	// See cmd/compile/internal/ssagen.emitArgInfo for the description of the
+	// encoding.
+	// These constants need to be in sync with the compiler.
+	const (
+		_endSeq         = 0xff
+		_startAgg       = 0xfe
+		_endAgg         = 0xfd
+		_dotdotdot      = 0xfc
+		_offsetTooLarge = 0xfb
+	)
+
+	const (
+		limit    = 10                       // print no more than 10 args/components
+		maxDepth = 5                        // no more than 5 layers of nesting
+		maxLen   = (maxDepth*3+2)*limit + 1 // max length of _FUNCDATA_ArgInfo (see the compiler side for reasoning)
+	)
+
+	p := (*[maxLen]uint8)(funcdata(f, _FUNCDATA_ArgInfo))
+	if p == nil {
+		return
+	}
+
+	liveInfo := funcdata(f, _FUNCDATA_ArgLiveInfo)
+	liveIdx := pcdatavalue(f, _PCDATA_ArgLiveIndex, pc, nil)
+	startOffset := uint8(0xff) // smallest offset that needs liveness info (slots with a lower offset is always live)
+	if liveInfo != nil {
+		startOffset = *(*uint8)(liveInfo)
+	}
+
+	isLive := func(off, slotIdx uint8) bool {
+		if liveInfo == nil || liveIdx <= 0 {
+			return true // no liveness info, always live
+		}
+		if off < startOffset {
+			return true
+		}
+		bits := *(*uint8)(add(liveInfo, uintptr(liveIdx)+uintptr(slotIdx/8)))
+		return bits&(1<<(slotIdx%8)) != 0
+	}
+
+	print1 := func(off, sz, slotIdx uint8) {
+		x := readUnaligned64(add(argp, uintptr(off)))
+		// mask out irrelevant bits
+		if sz < 8 {
+			shift := 64 - sz*8
+			if goarch.BigEndian {
+				x = x >> shift
+			} else {
+				x = x << shift >> shift
+			}
+		}
+		print(hex(x))
+		if !isLive(off, slotIdx) {
+			print("?")
+		}
+	}
+
+	start := true
+	printcomma := func() {
+		if !start {
+			print(", ")
+		}
+	}
+	pi := 0
+	slotIdx := uint8(0) // register arg spill slot index
+printloop:
+	for {
+		o := p[pi]
+		pi++
+		switch o {
+		case _endSeq:
+			break printloop
+		case _startAgg:
+			printcomma()
+			print("{")
+			start = true
+			continue
+		case _endAgg:
+			print("}")
+		case _dotdotdot:
+			printcomma()
+			print("...")
+		case _offsetTooLarge:
+			printcomma()
+			print("_")
+		default:
+			printcomma()
+			sz := p[pi]
+			pi++
+			print1(o, sz, slotIdx)
+			if o >= startOffset {
+				slotIdx++
+			}
+		}
+		start = false
+	}
+}
+
+// reflectMethodValue is a partial duplicate of reflect.makeFuncImpl
+// and reflect.methodValue.
+type reflectMethodValue struct {
+	fn     uintptr
+	stack  *bitvector // ptrmap for both args and results
+	argLen uintptr    // just args
+}
+
+// getArgInfoFast returns the argument frame information for a call to f.
+// It is short and inlineable. However, it does not handle all functions.
+// If ok reports false, you must call getArgInfo instead.
+// TODO(josharian): once we do mid-stack inlining,
+// call getArgInfo directly from getArgInfoFast and stop returning an ok bool.
+func getArgInfoFast(f funcInfo, needArgMap bool) (arglen uintptr, argmap *bitvector, ok bool) {
+	return uintptr(f.args), nil, !(needArgMap && f.args == _ArgsSizeUnknown)
+}
+
+// getArgInfo returns the argument frame information for a call to f
+// with call frame frame.
+//
+// This is used for both actual calls with active stack frames and for
+// deferred calls or goroutines that are not yet executing. If this is an actual
+// call, ctxt must be nil (getArgInfo will retrieve what it needs from
+// the active stack frame). If this is a deferred call or unstarted goroutine,
+// ctxt must be the function object that was deferred or go'd.
+func getArgInfo(frame *stkframe, f funcInfo, needArgMap bool, ctxt *funcval) (arglen uintptr, argmap *bitvector) {
+	arglen = uintptr(f.args)
+	if needArgMap && f.args == _ArgsSizeUnknown {
+		// Extract argument bitmaps for reflect stubs from the calls they made to reflect.
+		switch funcname(f) {
+		case "reflect.makeFuncStub", "reflect.methodValueCall":
+			// These take a *reflect.methodValue as their
+			// context register.
+			var mv *reflectMethodValue
+			var retValid bool
+			if ctxt != nil {
+				// This is not an actual call, but a
+				// deferred call or an unstarted goroutine.
+				// The function value is itself the *reflect.methodValue.
+				mv = (*reflectMethodValue)(unsafe.Pointer(ctxt))
+			} else {
+				// This is a real call that took the
+				// *reflect.methodValue as its context
+				// register and immediately saved it
+				// to 0(SP). Get the methodValue from
+				// 0(SP).
+				arg0 := frame.sp + sys.MinFrameSize
+				mv = *(**reflectMethodValue)(unsafe.Pointer(arg0))
+				// Figure out whether the return values are valid.
+				// Reflect will update this value after it copies
+				// in the return values.
+				retValid = *(*bool)(unsafe.Pointer(arg0 + 4*goarch.PtrSize))
+			}
+			if mv.fn != f.entry() {
+				print("runtime: confused by ", funcname(f), "\n")
+				throw("reflect mismatch")
+			}
+			bv := mv.stack
+			arglen = uintptr(bv.n * goarch.PtrSize)
+			if !retValid {
+				arglen = uintptr(mv.argLen) &^ (goarch.PtrSize - 1)
+			}
+			argmap = bv
+		}
+	}
+	return
+}
+
+// tracebackCgoContext handles tracing back a cgo context value, from
+// the context argument to setCgoTraceback, for the gentraceback
+// function. It returns the new value of n.
+func tracebackCgoContext(pcbuf *uintptr, printing bool, ctxt uintptr, n, max int) int {
+	var cgoPCs [32]uintptr
+	cgoContextPCs(ctxt, cgoPCs[:])
+	var arg cgoSymbolizerArg
+	anySymbolized := false
+	for _, pc := range cgoPCs {
+		if pc == 0 || n >= max {
+			break
+		}
+		if pcbuf != nil {
+			(*[1 << 20]uintptr)(unsafe.Pointer(pcbuf))[n] = pc
+		}
+		if printing {
+			if cgoSymbolizer == nil {
+				print("non-Go function at pc=", hex(pc), "\n")
+			} else {
+				c := printOneCgoTraceback(pc, max-n, &arg)
+				n += c - 1 // +1 a few lines down
+				anySymbolized = true
+			}
+		}
+		n++
+	}
+	if anySymbolized {
+		arg.pc = 0
+		callCgoSymbolizer(&arg)
+	}
+	return n
+}
+
+func printcreatedby(gp *g) {
+	// Show what created goroutine, except main goroutine (goid 1).
+	pc := gp.gopc
+	f := findfunc(pc)
+	if f.valid() && showframe(f, gp, false, funcID_normal, funcID_normal) && gp.goid != 1 {
+		printcreatedby1(f, pc)
+	}
+}
+
+func printcreatedby1(f funcInfo, pc uintptr) {
+	print("created by ", funcname(f), "\n")
+	tracepc := pc // back up to CALL instruction for funcline.
+	if pc > f.entry() {
+		tracepc -= sys.PCQuantum
+	}
+	file, line := funcline(f, tracepc)
+	print("\t", file, ":", line)
+	if pc > f.entry() {
+		print(" +", hex(pc-f.entry()))
+	}
+	print("\n")
+}
+
+func traceback(pc, sp, lr uintptr, gp *g) {
+	traceback1(pc, sp, lr, gp, 0)
+}
+
+// tracebacktrap is like traceback but expects that the PC and SP were obtained
+// from a trap, not from gp->sched or gp->syscallpc/gp->syscallsp or getcallerpc/getcallersp.
+// Because they are from a trap instead of from a saved pair,
+// the initial PC must not be rewound to the previous instruction.
+// (All the saved pairs record a PC that is a return address, so we
+// rewind it into the CALL instruction.)
+// If gp.m.libcall{g,pc,sp} information is available, it uses that information in preference to
+// the pc/sp/lr passed in.
+func tracebacktrap(pc, sp, lr uintptr, gp *g) {
+	if gp.m.libcallsp != 0 {
+		// We're in C code somewhere, traceback from the saved position.
+		traceback1(gp.m.libcallpc, gp.m.libcallsp, 0, gp.m.libcallg.ptr(), 0)
+		return
+	}
+	traceback1(pc, sp, lr, gp, _TraceTrap)
+}
+
+func traceback1(pc, sp, lr uintptr, gp *g, flags uint) {
+	// If the goroutine is in cgo, and we have a cgo traceback, print that.
+	if iscgo && gp.m != nil && gp.m.ncgo > 0 && gp.syscallsp != 0 && gp.m.cgoCallers != nil && gp.m.cgoCallers[0] != 0 {
+		// Lock cgoCallers so that a signal handler won't
+		// change it, copy the array, reset it, unlock it.
+		// We are locked to the thread and are not running
+		// concurrently with a signal handler.
+		// We just have to stop a signal handler from interrupting
+		// in the middle of our copy.
+		atomic.Store(&gp.m.cgoCallersUse, 1)
+		cgoCallers := *gp.m.cgoCallers
+		gp.m.cgoCallers[0] = 0
+		atomic.Store(&gp.m.cgoCallersUse, 0)
+
+		printCgoTraceback(&cgoCallers)
+	}
+
+	if readgstatus(gp)&^_Gscan == _Gsyscall {
+		// Override registers if blocked in system call.
+		pc = gp.syscallpc
+		sp = gp.syscallsp
+		flags &^= _TraceTrap
+	}
+	if gp.m != nil && gp.m.vdsoSP != 0 {
+		// Override registers if running in VDSO. This comes after the
+		// _Gsyscall check to cover VDSO calls after entersyscall.
+		pc = gp.m.vdsoPC
+		sp = gp.m.vdsoSP
+		flags &^= _TraceTrap
+	}
+
+	// Print traceback. By default, omits runtime frames.
+	// If that means we print nothing at all, repeat forcing all frames printed.
+	n := gentraceback(pc, sp, lr, gp, 0, nil, _TracebackMaxFrames, nil, nil, flags)
+	if n == 0 && (flags&_TraceRuntimeFrames) == 0 {
+		n = gentraceback(pc, sp, lr, gp, 0, nil, _TracebackMaxFrames, nil, nil, flags|_TraceRuntimeFrames)
+	}
+	if n == _TracebackMaxFrames {
+		print("...additional frames elided...\n")
+	}
+	printcreatedby(gp)
+
+	if gp.ancestors == nil {
+		return
+	}
+	for _, ancestor := range *gp.ancestors {
+		printAncestorTraceback(ancestor)
+	}
+}
+
+// printAncestorTraceback prints the traceback of the given ancestor.
+// TODO: Unify this with gentraceback and CallersFrames.
+func printAncestorTraceback(ancestor ancestorInfo) {
+	print("[originating from goroutine ", ancestor.goid, "]:\n")
+	for fidx, pc := range ancestor.pcs {
+		f := findfunc(pc) // f previously validated
+		if showfuncinfo(f, fidx == 0, funcID_normal, funcID_normal) {
+			printAncestorTracebackFuncInfo(f, pc)
+		}
+	}
+	if len(ancestor.pcs) == _TracebackMaxFrames {
+		print("...additional frames elided...\n")
+	}
+	// Show what created goroutine, except main goroutine (goid 1).
+	f := findfunc(ancestor.gopc)
+	if f.valid() && showfuncinfo(f, false, funcID_normal, funcID_normal) && ancestor.goid != 1 {
+		printcreatedby1(f, ancestor.gopc)
+	}
+}
+
+// printAncestorTraceback prints the given function info at a given pc
+// within an ancestor traceback. The precision of this info is reduced
+// due to only have access to the pcs at the time of the caller
+// goroutine being created.
+func printAncestorTracebackFuncInfo(f funcInfo, pc uintptr) {
+	name := funcname(f)
+	if inldata := funcdata(f, _FUNCDATA_InlTree); inldata != nil {
+		inltree := (*[1 << 20]inlinedCall)(inldata)
+		ix := pcdatavalue(f, _PCDATA_InlTreeIndex, pc, nil)
+		if ix >= 0 {
+			name = funcnameFromNameoff(f, inltree[ix].func_)
+		}
+	}
+	file, line := funcline(f, pc)
+	if name == "runtime.gopanic" {
+		name = "panic"
+	}
+	print(name, "(...)\n")
+	print("\t", file, ":", line)
+	if pc > f.entry() {
+		print(" +", hex(pc-f.entry()))
+	}
+	print("\n")
+}
+
+func callers(skip int, pcbuf []uintptr) int {
+	sp := getcallersp()
+	pc := getcallerpc()
+	gp := getg()
+	var n int
+	systemstack(func() {
+		n = gentraceback(pc, sp, 0, gp, skip, &pcbuf[0], len(pcbuf), nil, nil, 0)
+	})
+	return n
+}
+
+func gcallers(gp *g, skip int, pcbuf []uintptr) int {
+	return gentraceback(^uintptr(0), ^uintptr(0), 0, gp, skip, &pcbuf[0], len(pcbuf), nil, nil, 0)
+}
+
+// showframe reports whether the frame with the given characteristics should
+// be printed during a traceback.
+func showframe(f funcInfo, gp *g, firstFrame bool, funcID, childID funcID) bool {
+	g := getg()
+	if g.m.throwing >= throwTypeRuntime && gp != nil && (gp == g.m.curg || gp == g.m.caughtsig.ptr()) {
+		return true
+	}
+	return showfuncinfo(f, firstFrame, funcID, childID)
+}
+
+// showfuncinfo reports whether a function with the given characteristics should
+// be printed during a traceback.
+func showfuncinfo(f funcInfo, firstFrame bool, funcID, childID funcID) bool {
+	// Note that f may be a synthesized funcInfo for an inlined
+	// function, in which case only nameoff and funcID are set.
+
+	level, _, _ := gotraceback()
+	if level > 1 {
+		// Show all frames.
+		return true
+	}
+
+	if !f.valid() {
+		return false
+	}
+
+	if funcID == funcID_wrapper && elideWrapperCalling(childID) {
+		return false
+	}
+
+	name := funcname(f)
+
+	// Special case: always show runtime.gopanic frame
+	// in the middle of a stack trace, so that we can
+	// see the boundary between ordinary code and
+	// panic-induced deferred code.
+	// See golang.org/issue/5832.
+	if name == "runtime.gopanic" && !firstFrame {
+		return true
+	}
+
+	return bytealg.IndexByteString(name, '.') >= 0 && (!hasPrefix(name, "runtime.") || isExportedRuntime(name))
+}
+
+// isExportedRuntime reports whether name is an exported runtime function.
+// It is only for runtime functions, so ASCII A-Z is fine.
+func isExportedRuntime(name string) bool {
+	const n = len("runtime.")
+	return len(name) > n && name[:n] == "runtime." && 'A' <= name[n] && name[n] <= 'Z'
+}
+
+// elideWrapperCalling reports whether a wrapper function that called
+// function id should be elided from stack traces.
+func elideWrapperCalling(id funcID) bool {
+	// If the wrapper called a panic function instead of the
+	// wrapped function, we want to include it in stacks.
+	return !(id == funcID_gopanic || id == funcID_sigpanic || id == funcID_panicwrap)
+}
+
+var gStatusStrings = [...]string{
+	_Gidle:      "idle",
+	_Grunnable:  "runnable",
+	_Grunning:   "running",
+	_Gsyscall:   "syscall",
+	_Gwaiting:   "waiting",
+	_Gdead:      "dead",
+	_Gcopystack: "copystack",
+	_Gpreempted: "preempted",
+}
+
+func goroutineheader(gp *g) {
+	gpstatus := readgstatus(gp)
+
+	isScan := gpstatus&_Gscan != 0
+	gpstatus &^= _Gscan // drop the scan bit
+
+	// Basic string status
+	var status string
+	if 0 <= gpstatus && gpstatus < uint32(len(gStatusStrings)) {
+		status = gStatusStrings[gpstatus]
+	} else {
+		status = "???"
+	}
+
+	// Override.
+	if gpstatus == _Gwaiting && gp.waitreason != waitReasonZero {
+		status = gp.waitreason.String()
+	}
+
+	// approx time the G is blocked, in minutes
+	var waitfor int64
+	if (gpstatus == _Gwaiting || gpstatus == _Gsyscall) && gp.waitsince != 0 {
+		waitfor = (nanotime() - gp.waitsince) / 60e9
+	}
+	print("goroutine ", gp.goid, " [", status)
+	if isScan {
+		print(" (scan)")
+	}
+	if waitfor >= 1 {
+		print(", ", waitfor, " minutes")
+	}
+	if gp.lockedm != 0 {
+		print(", locked to thread")
+	}
+	print("]:\n")
+}
+
+func tracebackothers(me *g) {
+	level, _, _ := gotraceback()
+
+	// Show the current goroutine first, if we haven't already.
+	curgp := getg().m.curg
+	if curgp != nil && curgp != me {
+		print("\n")
+		goroutineheader(curgp)
+		traceback(^uintptr(0), ^uintptr(0), 0, curgp)
+	}
+
+	// We can't call locking forEachG here because this may be during fatal
+	// throw/panic, where locking could be out-of-order or a direct
+	// deadlock.
+	//
+	// Instead, use forEachGRace, which requires no locking. We don't lock
+	// against concurrent creation of new Gs, but even with allglock we may
+	// miss Gs created after this loop.
+	forEachGRace(func(gp *g) {
+		if gp == me || gp == curgp || readgstatus(gp) == _Gdead || isSystemGoroutine(gp, false) && level < 2 {
+			return
+		}
+		print("\n")
+		goroutineheader(gp)
+		// Note: gp.m == g.m occurs when tracebackothers is
+		// called from a signal handler initiated during a
+		// systemstack call. The original G is still in the
+		// running state, and we want to print its stack.
+		if gp.m != getg().m && readgstatus(gp)&^_Gscan == _Grunning {
+			print("\tgoroutine running on other thread; stack unavailable\n")
+			printcreatedby(gp)
+		} else {
+			traceback(^uintptr(0), ^uintptr(0), 0, gp)
+		}
+	})
+}
+
+// tracebackHexdump hexdumps part of stk around frame.sp and frame.fp
+// for debugging purposes. If the address bad is included in the
+// hexdumped range, it will mark it as well.
+func tracebackHexdump(stk stack, frame *stkframe, bad uintptr) {
+	const expand = 32 * goarch.PtrSize
+	const maxExpand = 256 * goarch.PtrSize
+	// Start around frame.sp.
+	lo, hi := frame.sp, frame.sp
+	// Expand to include frame.fp.
+	if frame.fp != 0 && frame.fp < lo {
+		lo = frame.fp
+	}
+	if frame.fp != 0 && frame.fp > hi {
+		hi = frame.fp
+	}
+	// Expand a bit more.
+	lo, hi = lo-expand, hi+expand
+	// But don't go too far from frame.sp.
+	if lo < frame.sp-maxExpand {
+		lo = frame.sp - maxExpand
+	}
+	if hi > frame.sp+maxExpand {
+		hi = frame.sp + maxExpand
+	}
+	// And don't go outside the stack bounds.
+	if lo < stk.lo {
+		lo = stk.lo
+	}
+	if hi > stk.hi {
+		hi = stk.hi
+	}
+
+	// Print the hex dump.
+	print("stack: frame={sp:", hex(frame.sp), ", fp:", hex(frame.fp), "} stack=[", hex(stk.lo), ",", hex(stk.hi), ")\n")
+	hexdumpWords(lo, hi, func(p uintptr) byte {
+		switch p {
+		case frame.fp:
+			return '>'
+		case frame.sp:
+			return '<'
+		case bad:
+			return '!'
+		}
+		return 0
+	})
+}
+
+// isSystemGoroutine reports whether the goroutine g must be omitted
+// in stack dumps and deadlock detector. This is any goroutine that
+// starts at a runtime.* entry point, except for runtime.main,
+// runtime.handleAsyncEvent (wasm only) and sometimes runtime.runfinq.
+//
+// If fixed is true, any goroutine that can vary between user and
+// system (that is, the finalizer goroutine) is considered a user
+// goroutine.
+func isSystemGoroutine(gp *g, fixed bool) bool {
+	// Keep this in sync with internal/trace.IsSystemGoroutine.
+	f := findfunc(gp.startpc)
+	if !f.valid() {
+		return false
+	}
+	if f.funcID == funcID_runtime_main || f.funcID == funcID_handleAsyncEvent {
+		return false
+	}
+	if f.funcID == funcID_runfinq {
+		// We include the finalizer goroutine if it's calling
+		// back into user code.
+		if fixed {
+			// This goroutine can vary. In fixed mode,
+			// always consider it a user goroutine.
+			return false
+		}
+		return !fingRunning
+	}
+	return hasPrefix(funcname(f), "runtime.")
+}
+
+// SetCgoTraceback records three C functions to use to gather
+// traceback information from C code and to convert that traceback
+// information into symbolic information. These are used when printing
+// stack traces for a program that uses cgo.
+//
+// The traceback and context functions may be called from a signal
+// handler, and must therefore use only async-signal safe functions.
+// The symbolizer function may be called while the program is
+// crashing, and so must be cautious about using memory.  None of the
+// functions may call back into Go.
+//
+// The context function will be called with a single argument, a
+// pointer to a struct:
+//
+//	struct {
+//		Context uintptr
+//	}
+//
+// In C syntax, this struct will be
+//
+//	struct {
+//		uintptr_t Context;
+//	};
+//
+// If the Context field is 0, the context function is being called to
+// record the current traceback context. It should record in the
+// Context field whatever information is needed about the current
+// point of execution to later produce a stack trace, probably the
+// stack pointer and PC. In this case the context function will be
+// called from C code.
+//
+// If the Context field is not 0, then it is a value returned by a
+// previous call to the context function. This case is called when the
+// context is no longer needed; that is, when the Go code is returning
+// to its C code caller. This permits the context function to release
+// any associated resources.
+//
+// While it would be correct for the context function to record a
+// complete a stack trace whenever it is called, and simply copy that
+// out in the traceback function, in a typical program the context
+// function will be called many times without ever recording a
+// traceback for that context. Recording a complete stack trace in a
+// call to the context function is likely to be inefficient.
+//
+// The traceback function will be called with a single argument, a
+// pointer to a struct:
+//
+//	struct {
+//		Context    uintptr
+//		SigContext uintptr
+//		Buf        *uintptr
+//		Max        uintptr
+//	}
+//
+// In C syntax, this struct will be
+//
+//	struct {
+//		uintptr_t  Context;
+//		uintptr_t  SigContext;
+//		uintptr_t* Buf;
+//		uintptr_t  Max;
+//	};
+//
+// The Context field will be zero to gather a traceback from the
+// current program execution point. In this case, the traceback
+// function will be called from C code.
+//
+// Otherwise Context will be a value previously returned by a call to
+// the context function. The traceback function should gather a stack
+// trace from that saved point in the program execution. The traceback
+// function may be called from an execution thread other than the one
+// that recorded the context, but only when the context is known to be
+// valid and unchanging. The traceback function may also be called
+// deeper in the call stack on the same thread that recorded the
+// context. The traceback function may be called multiple times with
+// the same Context value; it will usually be appropriate to cache the
+// result, if possible, the first time this is called for a specific
+// context value.
+//
+// If the traceback function is called from a signal handler on a Unix
+// system, SigContext will be the signal context argument passed to
+// the signal handler (a C ucontext_t* cast to uintptr_t). This may be
+// used to start tracing at the point where the signal occurred. If
+// the traceback function is not called from a signal handler,
+// SigContext will be zero.
+//
+// Buf is where the traceback information should be stored. It should
+// be PC values, such that Buf[0] is the PC of the caller, Buf[1] is
+// the PC of that function's caller, and so on.  Max is the maximum
+// number of entries to store.  The function should store a zero to
+// indicate the top of the stack, or that the caller is on a different
+// stack, presumably a Go stack.
+//
+// Unlike runtime.Callers, the PC values returned should, when passed
+// to the symbolizer function, return the file/line of the call
+// instruction.  No additional subtraction is required or appropriate.
+//
+// On all platforms, the traceback function is invoked when a call from
+// Go to C to Go requests a stack trace. On linux/amd64, linux/ppc64le,
+// linux/arm64, and freebsd/amd64, the traceback function is also invoked
+// when a signal is received by a thread that is executing a cgo call.
+// The traceback function should not make assumptions about when it is
+// called, as future versions of Go may make additional calls.
+//
+// The symbolizer function will be called with a single argument, a
+// pointer to a struct:
+//
+//	struct {
+//		PC      uintptr // program counter to fetch information for
+//		File    *byte   // file name (NUL terminated)
+//		Lineno  uintptr // line number
+//		Func    *byte   // function name (NUL terminated)
+//		Entry   uintptr // function entry point
+//		More    uintptr // set non-zero if more info for this PC
+//		Data    uintptr // unused by runtime, available for function
+//	}
+//
+// In C syntax, this struct will be
+//
+//	struct {
+//		uintptr_t PC;
+//		char*     File;
+//		uintptr_t Lineno;
+//		char*     Func;
+//		uintptr_t Entry;
+//		uintptr_t More;
+//		uintptr_t Data;
+//	};
+//
+// The PC field will be a value returned by a call to the traceback
+// function.
+//
+// The first time the function is called for a particular traceback,
+// all the fields except PC will be 0. The function should fill in the
+// other fields if possible, setting them to 0/nil if the information
+// is not available. The Data field may be used to store any useful
+// information across calls. The More field should be set to non-zero
+// if there is more information for this PC, zero otherwise. If More
+// is set non-zero, the function will be called again with the same
+// PC, and may return different information (this is intended for use
+// with inlined functions). If More is zero, the function will be
+// called with the next PC value in the traceback. When the traceback
+// is complete, the function will be called once more with PC set to
+// zero; this may be used to free any information. Each call will
+// leave the fields of the struct set to the same values they had upon
+// return, except for the PC field when the More field is zero. The
+// function must not keep a copy of the struct pointer between calls.
+//
+// When calling SetCgoTraceback, the version argument is the version
+// number of the structs that the functions expect to receive.
+// Currently this must be zero.
+//
+// The symbolizer function may be nil, in which case the results of
+// the traceback function will be displayed as numbers. If the
+// traceback function is nil, the symbolizer function will never be
+// called. The context function may be nil, in which case the
+// traceback function will only be called with the context field set
+// to zero.  If the context function is nil, then calls from Go to C
+// to Go will not show a traceback for the C portion of the call stack.
+//
+// SetCgoTraceback should be called only once, ideally from an init function.
+func SetCgoTraceback(version int, traceback, context, symbolizer unsafe.Pointer) {
+	if version != 0 {
+		panic("unsupported version")
+	}
+
+	if cgoTraceback != nil && cgoTraceback != traceback ||
+		cgoContext != nil && cgoContext != context ||
+		cgoSymbolizer != nil && cgoSymbolizer != symbolizer {
+		panic("call SetCgoTraceback only once")
+	}
+
+	cgoTraceback = traceback
+	cgoContext = context
+	cgoSymbolizer = symbolizer
+
+	// The context function is called when a C function calls a Go
+	// function. As such it is only called by C code in runtime/cgo.
+	if _cgo_set_context_function != nil {
+		cgocall(_cgo_set_context_function, context)
+	}
+}
+
+var cgoTraceback unsafe.Pointer
+var cgoContext unsafe.Pointer
+var cgoSymbolizer unsafe.Pointer
+
+// cgoTracebackArg is the type passed to cgoTraceback.
+type cgoTracebackArg struct {
+	context    uintptr
+	sigContext uintptr
+	buf        *uintptr
+	max        uintptr
+}
+
+// cgoContextArg is the type passed to the context function.
+type cgoContextArg struct {
+	context uintptr
+}
+
+// cgoSymbolizerArg is the type passed to cgoSymbolizer.
+type cgoSymbolizerArg struct {
+	pc       uintptr
+	file     *byte
+	lineno   uintptr
+	funcName *byte
+	entry    uintptr
+	more     uintptr
+	data     uintptr
+}
+
+// cgoTraceback prints a traceback of callers.
+func printCgoTraceback(callers *cgoCallers) {
+	if cgoSymbolizer == nil {
+		for _, c := range callers {
+			if c == 0 {
+				break
+			}
+			print("non-Go function at pc=", hex(c), "\n")
+		}
+		return
+	}
+
+	var arg cgoSymbolizerArg
+	for _, c := range callers {
+		if c == 0 {
+			break
+		}
+		printOneCgoTraceback(c, 0x7fffffff, &arg)
+	}
+	arg.pc = 0
+	callCgoSymbolizer(&arg)
+}
+
+// printOneCgoTraceback prints the traceback of a single cgo caller.
+// This can print more than one line because of inlining.
+// Returns the number of frames printed.
+func printOneCgoTraceback(pc uintptr, max int, arg *cgoSymbolizerArg) int {
+	c := 0
+	arg.pc = pc
+	for c <= max {
+		callCgoSymbolizer(arg)
+		if arg.funcName != nil {
+			// Note that we don't print any argument
+			// information here, not even parentheses.
+			// The symbolizer must add that if appropriate.
+			println(gostringnocopy(arg.funcName))
+		} else {
+			println("non-Go function")
+		}
+		print("\t")
+		if arg.file != nil {
+			print(gostringnocopy(arg.file), ":", arg.lineno, " ")
+		}
+		print("pc=", hex(pc), "\n")
+		c++
+		if arg.more == 0 {
+			break
+		}
+	}
+	return c
+}
+
+// callCgoSymbolizer calls the cgoSymbolizer function.
+func callCgoSymbolizer(arg *cgoSymbolizerArg) {
+	call := cgocall
+	if panicking > 0 || getg().m.curg != getg() {
+		// We do not want to call into the scheduler when panicking
+		// or when on the system stack.
+		call = asmcgocall
+	}
+	if msanenabled {
+		msanwrite(unsafe.Pointer(arg), unsafe.Sizeof(cgoSymbolizerArg{}))
+	}
+	if asanenabled {
+		asanwrite(unsafe.Pointer(arg), unsafe.Sizeof(cgoSymbolizerArg{}))
+	}
+	call(cgoSymbolizer, noescape(unsafe.Pointer(arg)))
+}
+
+// cgoContextPCs gets the PC values from a cgo traceback.
+func cgoContextPCs(ctxt uintptr, buf []uintptr) {
+	if cgoTraceback == nil {
+		return
+	}
+	call := cgocall
+	if panicking > 0 || getg().m.curg != getg() {
+		// We do not want to call into the scheduler when panicking
+		// or when on the system stack.
+		call = asmcgocall
+	}
+	arg := cgoTracebackArg{
+		context: ctxt,
+		buf:     (*uintptr)(noescape(unsafe.Pointer(&buf[0]))),
+		max:     uintptr(len(buf)),
+	}
+	if msanenabled {
+		msanwrite(unsafe.Pointer(&arg), unsafe.Sizeof(arg))
+	}
+	if asanenabled {
+		asanwrite(unsafe.Pointer(&arg), unsafe.Sizeof(arg))
+	}
+	call(cgoTraceback, noescape(unsafe.Pointer(&arg)))
+}
diff --git a/contrib/go/_std_1.19/src/runtime/type.go b/contrib/go/_std_1.19/src/runtime/type.go
new file mode 100644
index 0000000000..e8e7819ecf
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/type.go
@@ -0,0 +1,719 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Runtime type representation.
+
+package runtime
+
+import (
+	"internal/abi"
+	"unsafe"
+)
+
+// tflag is documented in reflect/type.go.
+//
+// tflag values must be kept in sync with copies in:
+//
+//	cmd/compile/internal/reflectdata/reflect.go
+//	cmd/link/internal/ld/decodesym.go
+//	reflect/type.go
+//	internal/reflectlite/type.go
+type tflag uint8
+
+const (
+	tflagUncommon      tflag = 1 << 0
+	tflagExtraStar     tflag = 1 << 1
+	tflagNamed         tflag = 1 << 2
+	tflagRegularMemory tflag = 1 << 3 // equal and hash can treat values of this type as a single region of t.size bytes
+)
+
+// Needs to be in sync with ../cmd/link/internal/ld/decodesym.go:/^func.commonsize,
+// ../cmd/compile/internal/reflectdata/reflect.go:/^func.dcommontype and
+// ../reflect/type.go:/^type.rtype.
+// ../internal/reflectlite/type.go:/^type.rtype.
+type _type struct {
+	size       uintptr
+	ptrdata    uintptr // size of memory prefix holding all pointers
+	hash       uint32
+	tflag      tflag
+	align      uint8
+	fieldAlign uint8
+	kind       uint8
+	// function for comparing objects of this type
+	// (ptr to object A, ptr to object B) -> ==?
+	equal func(unsafe.Pointer, unsafe.Pointer) bool
+	// gcdata stores the GC type data for the garbage collector.
+	// If the KindGCProg bit is set in kind, gcdata is a GC program.
+	// Otherwise it is a ptrmask bitmap. See mbitmap.go for details.
+	gcdata    *byte
+	str       nameOff
+	ptrToThis typeOff
+}
+
+func (t *_type) string() string {
+	s := t.nameOff(t.str).name()
+	if t.tflag&tflagExtraStar != 0 {
+		return s[1:]
+	}
+	return s
+}
+
+func (t *_type) uncommon() *uncommontype {
+	if t.tflag&tflagUncommon == 0 {
+		return nil
+	}
+	switch t.kind & kindMask {
+	case kindStruct:
+		type u struct {
+			structtype
+			u uncommontype
+		}
+		return &(*u)(unsafe.Pointer(t)).u
+	case kindPtr:
+		type u struct {
+			ptrtype
+			u uncommontype
+		}
+		return &(*u)(unsafe.Pointer(t)).u
+	case kindFunc:
+		type u struct {
+			functype
+			u uncommontype
+		}
+		return &(*u)(unsafe.Pointer(t)).u
+	case kindSlice:
+		type u struct {
+			slicetype
+			u uncommontype
+		}
+		return &(*u)(unsafe.Pointer(t)).u
+	case kindArray:
+		type u struct {
+			arraytype
+			u uncommontype
+		}
+		return &(*u)(unsafe.Pointer(t)).u
+	case kindChan:
+		type u struct {
+			chantype
+			u uncommontype
+		}
+		return &(*u)(unsafe.Pointer(t)).u
+	case kindMap:
+		type u struct {
+			maptype
+			u uncommontype
+		}
+		return &(*u)(unsafe.Pointer(t)).u
+	case kindInterface:
+		type u struct {
+			interfacetype
+			u uncommontype
+		}
+		return &(*u)(unsafe.Pointer(t)).u
+	default:
+		type u struct {
+			_type
+			u uncommontype
+		}
+		return &(*u)(unsafe.Pointer(t)).u
+	}
+}
+
+func (t *_type) name() string {
+	if t.tflag&tflagNamed == 0 {
+		return ""
+	}
+	s := t.string()
+	i := len(s) - 1
+	sqBrackets := 0
+	for i >= 0 && (s[i] != '.' || sqBrackets != 0) {
+		switch s[i] {
+		case ']':
+			sqBrackets++
+		case '[':
+			sqBrackets--
+		}
+		i--
+	}
+	return s[i+1:]
+}
+
+// pkgpath returns the path of the package where t was defined, if
+// available. This is not the same as the reflect package's PkgPath
+// method, in that it returns the package path for struct and interface
+// types, not just named types.
+func (t *_type) pkgpath() string {
+	if u := t.uncommon(); u != nil {
+		return t.nameOff(u.pkgpath).name()
+	}
+	switch t.kind & kindMask {
+	case kindStruct:
+		st := (*structtype)(unsafe.Pointer(t))
+		return st.pkgPath.name()
+	case kindInterface:
+		it := (*interfacetype)(unsafe.Pointer(t))
+		return it.pkgpath.name()
+	}
+	return ""
+}
+
+// reflectOffs holds type offsets defined at run time by the reflect package.
+//
+// When a type is defined at run time, its *rtype data lives on the heap.
+// There are a wide range of possible addresses the heap may use, that
+// may not be representable as a 32-bit offset. Moreover the GC may
+// one day start moving heap memory, in which case there is no stable
+// offset that can be defined.
+//
+// To provide stable offsets, we add pin *rtype objects in a global map
+// and treat the offset as an identifier. We use negative offsets that
+// do not overlap with any compile-time module offsets.
+//
+// Entries are created by reflect.addReflectOff.
+var reflectOffs struct {
+	lock mutex
+	next int32
+	m    map[int32]unsafe.Pointer
+	minv map[unsafe.Pointer]int32
+}
+
+func reflectOffsLock() {
+	lock(&reflectOffs.lock)
+	if raceenabled {
+		raceacquire(unsafe.Pointer(&reflectOffs.lock))
+	}
+}
+
+func reflectOffsUnlock() {
+	if raceenabled {
+		racerelease(unsafe.Pointer(&reflectOffs.lock))
+	}
+	unlock(&reflectOffs.lock)
+}
+
+func resolveNameOff(ptrInModule unsafe.Pointer, off nameOff) name {
+	if off == 0 {
+		return name{}
+	}
+	base := uintptr(ptrInModule)
+	for md := &firstmoduledata; md != nil; md = md.next {
+		if base >= md.types && base < md.etypes {
+			res := md.types + uintptr(off)
+			if res > md.etypes {
+				println("runtime: nameOff", hex(off), "out of range", hex(md.types), "-", hex(md.etypes))
+				throw("runtime: name offset out of range")
+			}
+			return name{(*byte)(unsafe.Pointer(res))}
+		}
+	}
+
+	// No module found. see if it is a run time name.
+	reflectOffsLock()
+	res, found := reflectOffs.m[int32(off)]
+	reflectOffsUnlock()
+	if !found {
+		println("runtime: nameOff", hex(off), "base", hex(base), "not in ranges:")
+		for next := &firstmoduledata; next != nil; next = next.next {
+			println("\ttypes", hex(next.types), "etypes", hex(next.etypes))
+		}
+		throw("runtime: name offset base pointer out of range")
+	}
+	return name{(*byte)(res)}
+}
+
+func (t *_type) nameOff(off nameOff) name {
+	return resolveNameOff(unsafe.Pointer(t), off)
+}
+
+func resolveTypeOff(ptrInModule unsafe.Pointer, off typeOff) *_type {
+	if off == 0 || off == -1 {
+		// -1 is the sentinel value for unreachable code.
+		// See cmd/link/internal/ld/data.go:relocsym.
+		return nil
+	}
+	base := uintptr(ptrInModule)
+	var md *moduledata
+	for next := &firstmoduledata; next != nil; next = next.next {
+		if base >= next.types && base < next.etypes {
+			md = next
+			break
+		}
+	}
+	if md == nil {
+		reflectOffsLock()
+		res := reflectOffs.m[int32(off)]
+		reflectOffsUnlock()
+		if res == nil {
+			println("runtime: typeOff", hex(off), "base", hex(base), "not in ranges:")
+			for next := &firstmoduledata; next != nil; next = next.next {
+				println("\ttypes", hex(next.types), "etypes", hex(next.etypes))
+			}
+			throw("runtime: type offset base pointer out of range")
+		}
+		return (*_type)(res)
+	}
+	if t := md.typemap[off]; t != nil {
+		return t
+	}
+	res := md.types + uintptr(off)
+	if res > md.etypes {
+		println("runtime: typeOff", hex(off), "out of range", hex(md.types), "-", hex(md.etypes))
+		throw("runtime: type offset out of range")
+	}
+	return (*_type)(unsafe.Pointer(res))
+}
+
+func (t *_type) typeOff(off typeOff) *_type {
+	return resolveTypeOff(unsafe.Pointer(t), off)
+}
+
+func (t *_type) textOff(off textOff) unsafe.Pointer {
+	if off == -1 {
+		// -1 is the sentinel value for unreachable code.
+		// See cmd/link/internal/ld/data.go:relocsym.
+		return unsafe.Pointer(abi.FuncPCABIInternal(unreachableMethod))
+	}
+	base := uintptr(unsafe.Pointer(t))
+	var md *moduledata
+	for next := &firstmoduledata; next != nil; next = next.next {
+		if base >= next.types && base < next.etypes {
+			md = next
+			break
+		}
+	}
+	if md == nil {
+		reflectOffsLock()
+		res := reflectOffs.m[int32(off)]
+		reflectOffsUnlock()
+		if res == nil {
+			println("runtime: textOff", hex(off), "base", hex(base), "not in ranges:")
+			for next := &firstmoduledata; next != nil; next = next.next {
+				println("\ttypes", hex(next.types), "etypes", hex(next.etypes))
+			}
+			throw("runtime: text offset base pointer out of range")
+		}
+		return res
+	}
+	res := md.textAddr(uint32(off))
+	return unsafe.Pointer(res)
+}
+
+func (t *functype) in() []*_type {
+	// See funcType in reflect/type.go for details on data layout.
+	uadd := uintptr(unsafe.Sizeof(functype{}))
+	if t.typ.tflag&tflagUncommon != 0 {
+		uadd += unsafe.Sizeof(uncommontype{})
+	}
+	return (*[1 << 20]*_type)(add(unsafe.Pointer(t), uadd))[:t.inCount]
+}
+
+func (t *functype) out() []*_type {
+	// See funcType in reflect/type.go for details on data layout.
+	uadd := uintptr(unsafe.Sizeof(functype{}))
+	if t.typ.tflag&tflagUncommon != 0 {
+		uadd += unsafe.Sizeof(uncommontype{})
+	}
+	outCount := t.outCount & (1<<15 - 1)
+	return (*[1 << 20]*_type)(add(unsafe.Pointer(t), uadd))[t.inCount : t.inCount+outCount]
+}
+
+func (t *functype) dotdotdot() bool {
+	return t.outCount&(1<<15) != 0
+}
+
+type nameOff int32
+type typeOff int32
+type textOff int32
+
+type method struct {
+	name nameOff
+	mtyp typeOff
+	ifn  textOff
+	tfn  textOff
+}
+
+type uncommontype struct {
+	pkgpath nameOff
+	mcount  uint16 // number of methods
+	xcount  uint16 // number of exported methods
+	moff    uint32 // offset from this uncommontype to [mcount]method
+	_       uint32 // unused
+}
+
+type imethod struct {
+	name nameOff
+	ityp typeOff
+}
+
+type interfacetype struct {
+	typ     _type
+	pkgpath name
+	mhdr    []imethod
+}
+
+type maptype struct {
+	typ    _type
+	key    *_type
+	elem   *_type
+	bucket *_type // internal type representing a hash bucket
+	// function for hashing keys (ptr to key, seed) -> hash
+	hasher     func(unsafe.Pointer, uintptr) uintptr
+	keysize    uint8  // size of key slot
+	elemsize   uint8  // size of elem slot
+	bucketsize uint16 // size of bucket
+	flags      uint32
+}
+
+// Note: flag values must match those used in the TMAP case
+// in ../cmd/compile/internal/reflectdata/reflect.go:writeType.
+func (mt *maptype) indirectkey() bool { // store ptr to key instead of key itself
+	return mt.flags&1 != 0
+}
+func (mt *maptype) indirectelem() bool { // store ptr to elem instead of elem itself
+	return mt.flags&2 != 0
+}
+func (mt *maptype) reflexivekey() bool { // true if k==k for all keys
+	return mt.flags&4 != 0
+}
+func (mt *maptype) needkeyupdate() bool { // true if we need to update key on an overwrite
+	return mt.flags&8 != 0
+}
+func (mt *maptype) hashMightPanic() bool { // true if hash function might panic
+	return mt.flags&16 != 0
+}
+
+type arraytype struct {
+	typ   _type
+	elem  *_type
+	slice *_type
+	len   uintptr
+}
+
+type chantype struct {
+	typ  _type
+	elem *_type
+	dir  uintptr
+}
+
+type slicetype struct {
+	typ  _type
+	elem *_type
+}
+
+type functype struct {
+	typ      _type
+	inCount  uint16
+	outCount uint16
+}
+
+type ptrtype struct {
+	typ  _type
+	elem *_type
+}
+
+type structfield struct {
+	name   name
+	typ    *_type
+	offset uintptr
+}
+
+type structtype struct {
+	typ     _type
+	pkgPath name
+	fields  []structfield
+}
+
+// name is an encoded type name with optional extra data.
+// See reflect/type.go for details.
+type name struct {
+	bytes *byte
+}
+
+func (n name) data(off int) *byte {
+	return (*byte)(add(unsafe.Pointer(n.bytes), uintptr(off)))
+}
+
+func (n name) isExported() bool {
+	return (*n.bytes)&(1<<0) != 0
+}
+
+func (n name) isEmbedded() bool {
+	return (*n.bytes)&(1<<3) != 0
+}
+
+func (n name) readvarint(off int) (int, int) {
+	v := 0
+	for i := 0; ; i++ {
+		x := *n.data(off + i)
+		v += int(x&0x7f) << (7 * i)
+		if x&0x80 == 0 {
+			return i + 1, v
+		}
+	}
+}
+
+func (n name) name() (s string) {
+	if n.bytes == nil {
+		return ""
+	}
+	i, l := n.readvarint(1)
+	if l == 0 {
+		return ""
+	}
+	hdr := (*stringStruct)(unsafe.Pointer(&s))
+	hdr.str = unsafe.Pointer(n.data(1 + i))
+	hdr.len = l
+	return
+}
+
+func (n name) tag() (s string) {
+	if *n.data(0)&(1<<1) == 0 {
+		return ""
+	}
+	i, l := n.readvarint(1)
+	i2, l2 := n.readvarint(1 + i + l)
+	hdr := (*stringStruct)(unsafe.Pointer(&s))
+	hdr.str = unsafe.Pointer(n.data(1 + i + l + i2))
+	hdr.len = l2
+	return
+}
+
+func (n name) pkgPath() string {
+	if n.bytes == nil || *n.data(0)&(1<<2) == 0 {
+		return ""
+	}
+	i, l := n.readvarint(1)
+	off := 1 + i + l
+	if *n.data(0)&(1<<1) != 0 {
+		i2, l2 := n.readvarint(off)
+		off += i2 + l2
+	}
+	var nameOff nameOff
+	copy((*[4]byte)(unsafe.Pointer(&nameOff))[:], (*[4]byte)(unsafe.Pointer(n.data(off)))[:])
+	pkgPathName := resolveNameOff(unsafe.Pointer(n.bytes), nameOff)
+	return pkgPathName.name()
+}
+
+func (n name) isBlank() bool {
+	if n.bytes == nil {
+		return false
+	}
+	_, l := n.readvarint(1)
+	return l == 1 && *n.data(2) == '_'
+}
+
+// typelinksinit scans the types from extra modules and builds the
+// moduledata typemap used to de-duplicate type pointers.
+func typelinksinit() {
+	if firstmoduledata.next == nil {
+		return
+	}
+	typehash := make(map[uint32][]*_type, len(firstmoduledata.typelinks))
+
+	modules := activeModules()
+	prev := modules[0]
+	for _, md := range modules[1:] {
+		// Collect types from the previous module into typehash.
+	collect:
+		for _, tl := range prev.typelinks {
+			var t *_type
+			if prev.typemap == nil {
+				t = (*_type)(unsafe.Pointer(prev.types + uintptr(tl)))
+			} else {
+				t = prev.typemap[typeOff(tl)]
+			}
+			// Add to typehash if not seen before.
+			tlist := typehash[t.hash]
+			for _, tcur := range tlist {
+				if tcur == t {
+					continue collect
+				}
+			}
+			typehash[t.hash] = append(tlist, t)
+		}
+
+		if md.typemap == nil {
+			// If any of this module's typelinks match a type from a
+			// prior module, prefer that prior type by adding the offset
+			// to this module's typemap.
+			tm := make(map[typeOff]*_type, len(md.typelinks))
+			pinnedTypemaps = append(pinnedTypemaps, tm)
+			md.typemap = tm
+			for _, tl := range md.typelinks {
+				t := (*_type)(unsafe.Pointer(md.types + uintptr(tl)))
+				for _, candidate := range typehash[t.hash] {
+					seen := map[_typePair]struct{}{}
+					if typesEqual(t, candidate, seen) {
+						t = candidate
+						break
+					}
+				}
+				md.typemap[typeOff(tl)] = t
+			}
+		}
+
+		prev = md
+	}
+}
+
+type _typePair struct {
+	t1 *_type
+	t2 *_type
+}
+
+// typesEqual reports whether two types are equal.
+//
+// Everywhere in the runtime and reflect packages, it is assumed that
+// there is exactly one *_type per Go type, so that pointer equality
+// can be used to test if types are equal. There is one place that
+// breaks this assumption: buildmode=shared. In this case a type can
+// appear as two different pieces of memory. This is hidden from the
+// runtime and reflect package by the per-module typemap built in
+// typelinksinit. It uses typesEqual to map types from later modules
+// back into earlier ones.
+//
+// Only typelinksinit needs this function.
+func typesEqual(t, v *_type, seen map[_typePair]struct{}) bool {
+	tp := _typePair{t, v}
+	if _, ok := seen[tp]; ok {
+		return true
+	}
+
+	// mark these types as seen, and thus equivalent which prevents an infinite loop if
+	// the two types are identical, but recursively defined and loaded from
+	// different modules
+	seen[tp] = struct{}{}
+
+	if t == v {
+		return true
+	}
+	kind := t.kind & kindMask
+	if kind != v.kind&kindMask {
+		return false
+	}
+	if t.string() != v.string() {
+		return false
+	}
+	ut := t.uncommon()
+	uv := v.uncommon()
+	if ut != nil || uv != nil {
+		if ut == nil || uv == nil {
+			return false
+		}
+		pkgpatht := t.nameOff(ut.pkgpath).name()
+		pkgpathv := v.nameOff(uv.pkgpath).name()
+		if pkgpatht != pkgpathv {
+			return false
+		}
+	}
+	if kindBool <= kind && kind <= kindComplex128 {
+		return true
+	}
+	switch kind {
+	case kindString, kindUnsafePointer:
+		return true
+	case kindArray:
+		at := (*arraytype)(unsafe.Pointer(t))
+		av := (*arraytype)(unsafe.Pointer(v))
+		return typesEqual(at.elem, av.elem, seen) && at.len == av.len
+	case kindChan:
+		ct := (*chantype)(unsafe.Pointer(t))
+		cv := (*chantype)(unsafe.Pointer(v))
+		return ct.dir == cv.dir && typesEqual(ct.elem, cv.elem, seen)
+	case kindFunc:
+		ft := (*functype)(unsafe.Pointer(t))
+		fv := (*functype)(unsafe.Pointer(v))
+		if ft.outCount != fv.outCount || ft.inCount != fv.inCount {
+			return false
+		}
+		tin, vin := ft.in(), fv.in()
+		for i := 0; i < len(tin); i++ {
+			if !typesEqual(tin[i], vin[i], seen) {
+				return false
+			}
+		}
+		tout, vout := ft.out(), fv.out()
+		for i := 0; i < len(tout); i++ {
+			if !typesEqual(tout[i], vout[i], seen) {
+				return false
+			}
+		}
+		return true
+	case kindInterface:
+		it := (*interfacetype)(unsafe.Pointer(t))
+		iv := (*interfacetype)(unsafe.Pointer(v))
+		if it.pkgpath.name() != iv.pkgpath.name() {
+			return false
+		}
+		if len(it.mhdr) != len(iv.mhdr) {
+			return false
+		}
+		for i := range it.mhdr {
+			tm := &it.mhdr[i]
+			vm := &iv.mhdr[i]
+			// Note the mhdr array can be relocated from
+			// another module. See #17724.
+			tname := resolveNameOff(unsafe.Pointer(tm), tm.name)
+			vname := resolveNameOff(unsafe.Pointer(vm), vm.name)
+			if tname.name() != vname.name() {
+				return false
+			}
+			if tname.pkgPath() != vname.pkgPath() {
+				return false
+			}
+			tityp := resolveTypeOff(unsafe.Pointer(tm), tm.ityp)
+			vityp := resolveTypeOff(unsafe.Pointer(vm), vm.ityp)
+			if !typesEqual(tityp, vityp, seen) {
+				return false
+			}
+		}
+		return true
+	case kindMap:
+		mt := (*maptype)(unsafe.Pointer(t))
+		mv := (*maptype)(unsafe.Pointer(v))
+		return typesEqual(mt.key, mv.key, seen) && typesEqual(mt.elem, mv.elem, seen)
+	case kindPtr:
+		pt := (*ptrtype)(unsafe.Pointer(t))
+		pv := (*ptrtype)(unsafe.Pointer(v))
+		return typesEqual(pt.elem, pv.elem, seen)
+	case kindSlice:
+		st := (*slicetype)(unsafe.Pointer(t))
+		sv := (*slicetype)(unsafe.Pointer(v))
+		return typesEqual(st.elem, sv.elem, seen)
+	case kindStruct:
+		st := (*structtype)(unsafe.Pointer(t))
+		sv := (*structtype)(unsafe.Pointer(v))
+		if len(st.fields) != len(sv.fields) {
+			return false
+		}
+		if st.pkgPath.name() != sv.pkgPath.name() {
+			return false
+		}
+		for i := range st.fields {
+			tf := &st.fields[i]
+			vf := &sv.fields[i]
+			if tf.name.name() != vf.name.name() {
+				return false
+			}
+			if !typesEqual(tf.typ, vf.typ, seen) {
+				return false
+			}
+			if tf.name.tag() != vf.name.tag() {
+				return false
+			}
+			if tf.offset != vf.offset {
+				return false
+			}
+			if tf.name.isEmbedded() != vf.name.isEmbedded() {
+				return false
+			}
+		}
+		return true
+	default:
+		println("runtime: impossible type kind", kind)
+		throw("runtime: impossible type kind")
+		return false
+	}
+}
diff --git a/contrib/go/_std_1.18/src/runtime/typekind.go b/contrib/go/_std_1.19/src/runtime/typekind.go
index 7087a9b046..7087a9b046 100644
--- a/contrib/go/_std_1.18/src/runtime/typekind.go
+++ b/contrib/go/_std_1.19/src/runtime/typekind.go
diff --git a/contrib/go/_std_1.18/src/runtime/utf8.go b/contrib/go/_std_1.19/src/runtime/utf8.go
index 52b757662d..52b757662d 100644
--- a/contrib/go/_std_1.18/src/runtime/utf8.go
+++ b/contrib/go/_std_1.19/src/runtime/utf8.go
diff --git a/contrib/go/_std_1.19/src/runtime/vdso_elf64.go b/contrib/go/_std_1.19/src/runtime/vdso_elf64.go
new file mode 100644
index 0000000000..d41d25e770
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/vdso_elf64.go
@@ -0,0 +1,79 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build linux && (amd64 || arm64 || loong64 || mips64 || mips64le || ppc64 || ppc64le || riscv64 || s390x)
+
+package runtime
+
+// ELF64 structure definitions for use by the vDSO loader
+
+type elfSym struct {
+	st_name  uint32
+	st_info  byte
+	st_other byte
+	st_shndx uint16
+	st_value uint64
+	st_size  uint64
+}
+
+type elfVerdef struct {
+	vd_version uint16 /* Version revision */
+	vd_flags   uint16 /* Version information */
+	vd_ndx     uint16 /* Version Index */
+	vd_cnt     uint16 /* Number of associated aux entries */
+	vd_hash    uint32 /* Version name hash value */
+	vd_aux     uint32 /* Offset in bytes to verdaux array */
+	vd_next    uint32 /* Offset in bytes to next verdef entry */
+}
+
+type elfEhdr struct {
+	e_ident     [_EI_NIDENT]byte /* Magic number and other info */
+	e_type      uint16           /* Object file type */
+	e_machine   uint16           /* Architecture */
+	e_version   uint32           /* Object file version */
+	e_entry     uint64           /* Entry point virtual address */
+	e_phoff     uint64           /* Program header table file offset */
+	e_shoff     uint64           /* Section header table file offset */
+	e_flags     uint32           /* Processor-specific flags */
+	e_ehsize    uint16           /* ELF header size in bytes */
+	e_phentsize uint16           /* Program header table entry size */
+	e_phnum     uint16           /* Program header table entry count */
+	e_shentsize uint16           /* Section header table entry size */
+	e_shnum     uint16           /* Section header table entry count */
+	e_shstrndx  uint16           /* Section header string table index */
+}
+
+type elfPhdr struct {
+	p_type   uint32 /* Segment type */
+	p_flags  uint32 /* Segment flags */
+	p_offset uint64 /* Segment file offset */
+	p_vaddr  uint64 /* Segment virtual address */
+	p_paddr  uint64 /* Segment physical address */
+	p_filesz uint64 /* Segment size in file */
+	p_memsz  uint64 /* Segment size in memory */
+	p_align  uint64 /* Segment alignment */
+}
+
+type elfShdr struct {
+	sh_name      uint32 /* Section name (string tbl index) */
+	sh_type      uint32 /* Section type */
+	sh_flags     uint64 /* Section flags */
+	sh_addr      uint64 /* Section virtual addr at execution */
+	sh_offset    uint64 /* Section file offset */
+	sh_size      uint64 /* Section size in bytes */
+	sh_link      uint32 /* Link to another section */
+	sh_info      uint32 /* Additional section information */
+	sh_addralign uint64 /* Section alignment */
+	sh_entsize   uint64 /* Entry size if section holds table */
+}
+
+type elfDyn struct {
+	d_tag int64  /* Dynamic entry type */
+	d_val uint64 /* Integer value */
+}
+
+type elfVerdaux struct {
+	vda_name uint32 /* Version or dependency names */
+	vda_next uint32 /* Offset in bytes to next verdaux entry */
+}
diff --git a/contrib/go/_std_1.19/src/runtime/vdso_in_none.go b/contrib/go/_std_1.19/src/runtime/vdso_in_none.go
new file mode 100644
index 0000000000..3a6ee6f049
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/vdso_in_none.go
@@ -0,0 +1,13 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build (linux && !386 && !amd64 && !arm && !arm64 && !loong64 && !mips64 && !mips64le && !ppc64 && !ppc64le && !riscv64 && !s390x) || !linux
+
+package runtime
+
+// A dummy version of inVDSOPage for targets that don't use a VDSO.
+
+func inVDSOPage(pc uintptr) bool {
+	return false
+}
diff --git a/contrib/go/_std_1.19/src/runtime/vdso_linux.go b/contrib/go/_std_1.19/src/runtime/vdso_linux.go
new file mode 100644
index 0000000000..4523615711
--- /dev/null
+++ b/contrib/go/_std_1.19/src/runtime/vdso_linux.go
@@ -0,0 +1,295 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build linux && (386 || amd64 || arm || arm64 || loong64 || mips64 || mips64le || ppc64 || ppc64le || riscv64 || s390x)
+
+package runtime
+
+import "unsafe"
+
+// Look up symbols in the Linux vDSO.
+
+// This code was originally based on the sample Linux vDSO parser at
+// https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/tools/testing/selftests/vDSO/parse_vdso.c
+
+// This implements the ELF dynamic linking spec at
+// http://sco.com/developers/gabi/latest/ch5.dynamic.html
+
+// The version section is documented at
+// https://refspecs.linuxfoundation.org/LSB_3.2.0/LSB-Core-generic/LSB-Core-generic/symversion.html
+
+const (
+	_AT_SYSINFO_EHDR = 33
+
+	_PT_LOAD    = 1 /* Loadable program segment */
+	_PT_DYNAMIC = 2 /* Dynamic linking information */
+
+	_DT_NULL     = 0          /* Marks end of dynamic section */
+	_DT_HASH     = 4          /* Dynamic symbol hash table */
+	_DT_STRTAB   = 5          /* Address of string table */
+	_DT_SYMTAB   = 6          /* Address of symbol table */
+	_DT_GNU_HASH = 0x6ffffef5 /* GNU-style dynamic symbol hash table */
+	_DT_VERSYM   = 0x6ffffff0
+	_DT_VERDEF   = 0x6ffffffc
+
+	_VER_FLG_BASE = 0x1 /* Version definition of file itself */
+
+	_SHN_UNDEF = 0 /* Undefined section */
+
+	_SHT_DYNSYM = 11 /* Dynamic linker symbol table */
+
+	_STT_FUNC = 2 /* Symbol is a code object */
+
+	_STT_NOTYPE = 0 /* Symbol type is not specified */
+
+	_STB_GLOBAL = 1 /* Global symbol */
+	_STB_WEAK   = 2 /* Weak symbol */
+
+	_EI_NIDENT = 16
+
+	// Maximum indices for the array types used when traversing the vDSO ELF structures.
+	// Computed from architecture-specific max provided by vdso_linux_*.go
+	vdsoSymTabSize     = vdsoArrayMax / unsafe.Sizeof(elfSym{})
+	vdsoDynSize        = vdsoArrayMax / unsafe.Sizeof(elfDyn{})
+	vdsoSymStringsSize = vdsoArrayMax     // byte
+	vdsoVerSymSize     = vdsoArrayMax / 2 // uint16
+	vdsoHashSize       = vdsoArrayMax / 4 // uint32
+
+	// vdsoBloomSizeScale is a scaling factor for gnuhash tables which are uint32 indexed,
+	// but contain uintptrs
+	vdsoBloomSizeScale = unsafe.Sizeof(uintptr(0)) / 4 // uint32
+)
+
+/* How to extract and insert information held in the st_info field.  */
+func _ELF_ST_BIND(val byte) byte { return val >> 4 }
+func _ELF_ST_TYPE(val byte) byte { return val & 0xf }
+
+type vdsoSymbolKey struct {
+	name    string
+	symHash uint32
+	gnuHash uint32
+	ptr     *uintptr
+}
+
+type vdsoVersionKey struct {
+	version string
+	verHash uint32
+}
+
+type vdsoInfo struct {
+	valid bool
+
+	/* Load information */
+	loadAddr   uintptr
+	loadOffset uintptr /* loadAddr - recorded vaddr */
+
+	/* Symbol table */
+	symtab     *[vdsoSymTabSize]elfSym
+	symstrings *[vdsoSymStringsSize]byte
+	chain      []uint32
+	bucket     []uint32
+	symOff     uint32
+	isGNUHash  bool
+
+	/* Version table */
+	versym *[vdsoVerSymSize]uint16
+	verdef *elfVerdef
+}
+
+// see vdso_linux_*.go for vdsoSymbolKeys[] and vdso*Sym vars
+
+func vdsoInitFromSysinfoEhdr(info *vdsoInfo, hdr *elfEhdr) {
+	info.valid = false
+	info.loadAddr = uintptr(unsafe.Pointer(hdr))
+
+	pt := unsafe.Pointer(info.loadAddr + uintptr(hdr.e_phoff))
+
+	// We need two things from the segment table: the load offset
+	// and the dynamic table.
+	var foundVaddr bool
+	var dyn *[vdsoDynSize]elfDyn
+	for i := uint16(0); i < hdr.e_phnum; i++ {
+		pt := (*elfPhdr)(add(pt, uintptr(i)*unsafe.Sizeof(elfPhdr{})))
+		switch pt.p_type {
+		case _PT_LOAD:
+			if !foundVaddr {
+				foundVaddr = true
+				info.loadOffset = info.loadAddr + uintptr(pt.p_offset-pt.p_vaddr)
+			}
+
+		case _PT_DYNAMIC:
+			dyn = (*[vdsoDynSize]elfDyn)(unsafe.Pointer(info.loadAddr + uintptr(pt.p_offset)))
+		}
+	}
+
+	if !foundVaddr || dyn == nil {
+		return // Failed
+	}
+
+	// Fish out the useful bits of the dynamic table.
+
+	var hash, gnuhash *[vdsoHashSize]uint32
+	info.symstrings = nil
+	info.symtab = nil
+	info.versym = nil
+	info.verdef = nil
+	for i := 0; dyn[i].d_tag != _DT_NULL; i++ {
+		dt := &dyn[i]
+		p := info.loadOffset + uintptr(dt.d_val)
+		switch dt.d_tag {
+		case _DT_STRTAB:
+			info.symstrings = (*[vdsoSymStringsSize]byte)(unsafe.Pointer(p))
+		case _DT_SYMTAB:
+			info.symtab = (*[vdsoSymTabSize]elfSym)(unsafe.Pointer(p))
+		case _DT_HASH:
+			hash = (*[vdsoHashSize]uint32)(unsafe.Pointer(p))
+		case _DT_GNU_HASH:
+			gnuhash = (*[vdsoHashSize]uint32)(unsafe.Pointer(p))
+		case _DT_VERSYM:
+			info.versym = (*[vdsoVerSymSize]uint16)(unsafe.Pointer(p))
+		case _DT_VERDEF:
+			info.verdef = (*elfVerdef)(unsafe.Pointer(p))
+		}
+	}
+
+	if info.symstrings == nil || info.symtab == nil || (hash == nil && gnuhash == nil) {
+		return // Failed
+	}
+
+	if info.verdef == nil {
+		info.versym = nil
+	}
+
+	if gnuhash != nil {
+		// Parse the GNU hash table header.
+		nbucket := gnuhash[0]
+		info.symOff = gnuhash[1]
+		bloomSize := gnuhash[2]
+		info.bucket = gnuhash[4+bloomSize*uint32(vdsoBloomSizeScale):][:nbucket]
+		info.chain = gnuhash[4+bloomSize*uint32(vdsoBloomSizeScale)+nbucket:]
+		info.isGNUHash = true
+	} else {
+		// Parse the hash table header.
+		nbucket := hash[0]
+		nchain := hash[1]
+		info.bucket = hash[2 : 2+nbucket]
+		info.chain = hash[2+nbucket : 2+nbucket+nchain]
+	}
+
+	// That's all we need.
+	info.valid = true
+}
+
+func vdsoFindVersion(info *vdsoInfo, ver *vdsoVersionKey) int32 {
+	if !info.valid {
+		return 0
+	}
+
+	def := info.verdef
+	for {
+		if def.vd_flags&_VER_FLG_BASE == 0 {
+			aux := (*elfVerdaux)(add(unsafe.Pointer(def), uintptr(def.vd_aux)))
+			if def.vd_hash == ver.verHash && ver.version == gostringnocopy(&info.symstrings[aux.vda_name]) {
+				return int32(def.vd_ndx & 0x7fff)
+			}
+		}
+
+		if def.vd_next == 0 {
+			break
+		}
+		def = (*elfVerdef)(add(unsafe.Pointer(def), uintptr(def.vd_next)))
+	}
+
+	return -1 // cannot match any version
+}
+
+func vdsoParseSymbols(info *vdsoInfo, version int32) {
+	if !info.valid {
+		return
+	}
+
+	apply := func(symIndex uint32, k vdsoSymbolKey) bool {
+		sym := &info.symtab[symIndex]
+		typ := _ELF_ST_TYPE(sym.st_info)
+		bind := _ELF_ST_BIND(sym.st_info)
+		// On ppc64x, VDSO functions are of type _STT_NOTYPE.
+		if typ != _STT_FUNC && typ != _STT_NOTYPE || bind != _STB_GLOBAL && bind != _STB_WEAK || sym.st_shndx == _SHN_UNDEF {
+			return false
+		}
+		if k.name != gostringnocopy(&info.symstrings[sym.st_name]) {
+			return false
+		}
+		// Check symbol version.
+		if info.versym != nil && version != 0 && int32(info.versym[symIndex]&0x7fff) != version {
+			return false
+		}
+
+		*k.ptr = info.loadOffset + uintptr(sym.st_value)
+		return true
+	}
+
+	if !info.isGNUHash {
+		// Old-style DT_HASH table.
+		for _, k := range vdsoSymbolKeys {
+			if len(info.bucket) > 0 {
+				for chain := info.bucket[k.symHash%uint32(len(info.bucket))]; chain != 0; chain = info.chain[chain] {
+					if apply(chain, k) {
+						break
+					}
+				}
+			}
+		}
+		return
+	}
+
+	// New-style DT_GNU_HASH table.
+	for _, k := range vdsoSymbolKeys {
+		symIndex := info.bucket[k.gnuHash%uint32(len(info.bucket))]
+		if symIndex < info.symOff {
+			continue
+		}
+		for ; ; symIndex++ {
+			hash := info.chain[symIndex-info.symOff]
+			if hash|1 == k.gnuHash|1 {
+				// Found a hash match.
+				if apply(symIndex, k) {
+					break
+				}
+			}
+			if hash&1 != 0 {
+				// End of chain.
+				break
+			}
+		}
+	}
+}
+
+func vdsoauxv(tag, val uintptr) {
+	switch tag {
+	case _AT_SYSINFO_EHDR:
+		if val == 0 {
+			// Something went wrong
+			return
+		}
+		var info vdsoInfo
+		// TODO(rsc): I don't understand why the compiler thinks info escapes
+		// when passed to the three functions below.
+		info1 := (*vdsoInfo)(noescape(unsafe.Pointer(&info)))
+		vdsoInitFromSysinfoEhdr(info1, (*elfEhdr)(unsafe.Pointer(val)))
+		vdsoParseSymbols(info1, vdsoFindVersion(info1, &vdsoLinuxVersion))
+	}
+}
+
+// vdsoMarker reports whether PC is on the VDSO page.
+//
+//go:nosplit
+func inVDSOPage(pc uintptr) bool {
+	for _, k := range vdsoSymbolKeys {
+		if *k.ptr != 0 {
+			page := *k.ptr &^ (physPageSize - 1)
+			return pc >= page && pc < page+physPageSize
+		}
+	}
+	return false
+}
diff --git a/contrib/go/_std_1.18/src/runtime/vdso_linux_amd64.go b/contrib/go/_std_1.19/src/runtime/vdso_linux_amd64.go
index 4e9f748f4a..4e9f748f4a 100644
--- a/contrib/go/_std_1.18/src/runtime/vdso_linux_amd64.go
+++ b/contrib/go/_std_1.19/src/runtime/vdso_linux_amd64.go
diff --git a/contrib/go/_std_1.18/src/runtime/write_err.go b/contrib/go/_std_1.19/src/runtime/write_err.go
index 81ae872e9c..81ae872e9c 100644
--- a/contrib/go/_std_1.18/src/runtime/write_err.go
+++ b/contrib/go/_std_1.19/src/runtime/write_err.go
diff --git a/contrib/go/_std_1.19/src/sort/search.go b/contrib/go/_std_1.19/src/sort/search.go
new file mode 100644
index 0000000000..874e40813d
--- /dev/null
+++ b/contrib/go/_std_1.19/src/sort/search.go
@@ -0,0 +1,150 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements binary search.
+
+package sort
+
+// Search uses binary search to find and return the smallest index i
+// in [0, n) at which f(i) is true, assuming that on the range [0, n),
+// f(i) == true implies f(i+1) == true. That is, Search requires that
+// f is false for some (possibly empty) prefix of the input range [0, n)
+// and then true for the (possibly empty) remainder; Search returns
+// the first true index. If there is no such index, Search returns n.
+// (Note that the "not found" return value is not -1 as in, for instance,
+// strings.Index.)
+// Search calls f(i) only for i in the range [0, n).
+//
+// A common use of Search is to find the index i for a value x in
+// a sorted, indexable data structure such as an array or slice.
+// In this case, the argument f, typically a closure, captures the value
+// to be searched for, and how the data structure is indexed and
+// ordered.
+//
+// For instance, given a slice data sorted in ascending order,
+// the call Search(len(data), func(i int) bool { return data[i] >= 23 })
+// returns the smallest index i such that data[i] >= 23. If the caller
+// wants to find whether 23 is in the slice, it must test data[i] == 23
+// separately.
+//
+// Searching data sorted in descending order would use the <=
+// operator instead of the >= operator.
+//
+// To complete the example above, the following code tries to find the value
+// x in an integer slice data sorted in ascending order:
+//
+//	x := 23
+//	i := sort.Search(len(data), func(i int) bool { return data[i] >= x })
+//	if i < len(data) && data[i] == x {
+//		// x is present at data[i]
+//	} else {
+//		// x is not present in data,
+//		// but i is the index where it would be inserted.
+//	}
+//
+// As a more whimsical example, this program guesses your number:
+//
+//	func GuessingGame() {
+//		var s string
+//		fmt.Printf("Pick an integer from 0 to 100.\n")
+//		answer := sort.Search(100, func(i int) bool {
+//			fmt.Printf("Is your number <= %d? ", i)
+//			fmt.Scanf("%s", &s)
+//			return s != "" && s[0] == 'y'
+//		})
+//		fmt.Printf("Your number is %d.\n", answer)
+//	}
+func Search(n int, f func(int) bool) int {
+	// Define f(-1) == false and f(n) == true.
+	// Invariant: f(i-1) == false, f(j) == true.
+	i, j := 0, n
+	for i < j {
+		h := int(uint(i+j) >> 1) // avoid overflow when computing h
+		// i ≤ h < j
+		if !f(h) {
+			i = h + 1 // preserves f(i-1) == false
+		} else {
+			j = h // preserves f(j) == true
+		}
+	}
+	// i == j, f(i-1) == false, and f(j) (= f(i)) == true  =>  answer is i.
+	return i
+}
+
+// Find uses binary search to find and return the smallest index i in [0, n)
+// at which cmp(i) <= 0. If there is no such index i, Find returns i = n.
+// The found result is true if i < n and cmp(i) == 0.
+// Find calls cmp(i) only for i in the range [0, n).
+//
+// To permit binary search, Find requires that cmp(i) > 0 for a leading
+// prefix of the range, cmp(i) == 0 in the middle, and cmp(i) < 0 for
+// the final suffix of the range. (Each subrange could be empty.)
+// The usual way to establish this condition is to interpret cmp(i)
+// as a comparison of a desired target value t against entry i in an
+// underlying indexed data structure x, returning <0, 0, and >0
+// when t < x[i], t == x[i], and t > x[i], respectively.
+//
+// For example, to look for a particular string in a sorted, random-access
+// list of strings:
+//
+//	i, found := sort.Find(x.Len(), func(i int) int {
+//	    return strings.Compare(target, x.At(i))
+//	})
+//	if found {
+//	    fmt.Printf("found %s at entry %d\n", target, i)
+//	} else {
+//	    fmt.Printf("%s not found, would insert at %d", target, i)
+//	}
+func Find(n int, cmp func(int) int) (i int, found bool) {
+	// The invariants here are similar to the ones in Search.
+	// Define cmp(-1) > 0 and cmp(n) <= 0
+	// Invariant: cmp(i-1) > 0, cmp(j) <= 0
+	i, j := 0, n
+	for i < j {
+		h := int(uint(i+j) >> 1) // avoid overflow when computing h
+		// i ≤ h < j
+		if cmp(h) > 0 {
+			i = h + 1 // preserves cmp(i-1) > 0
+		} else {
+			j = h // preserves cmp(j) <= 0
+		}
+	}
+	// i == j, cmp(i-1) > 0 and cmp(j) <= 0
+	return i, i < n && cmp(i) == 0
+}
+
+// Convenience wrappers for common cases.
+
+// SearchInts searches for x in a sorted slice of ints and returns the index
+// as specified by Search. The return value is the index to insert x if x is
+// not present (it could be len(a)).
+// The slice must be sorted in ascending order.
+func SearchInts(a []int, x int) int {
+	return Search(len(a), func(i int) bool { return a[i] >= x })
+}
+
+// SearchFloat64s searches for x in a sorted slice of float64s and returns the index
+// as specified by Search. The return value is the index to insert x if x is not
+// present (it could be len(a)).
+// The slice must be sorted in ascending order.
+func SearchFloat64s(a []float64, x float64) int {
+	return Search(len(a), func(i int) bool { return a[i] >= x })
+}
+
+// SearchStrings searches for x in a sorted slice of strings and returns the index
+// as specified by Search. The return value is the index to insert x if x is not
+// present (it could be len(a)).
+// The slice must be sorted in ascending order.
+func SearchStrings(a []string, x string) int {
+	return Search(len(a), func(i int) bool { return a[i] >= x })
+}
+
+// Search returns the result of applying SearchInts to the receiver and x.
+func (p IntSlice) Search(x int) int { return SearchInts(p, x) }
+
+// Search returns the result of applying SearchFloat64s to the receiver and x.
+func (p Float64Slice) Search(x float64) int { return SearchFloat64s(p, x) }
+
+// Search returns the result of applying SearchStrings to the receiver and x.
+func (p StringSlice) Search(x string) int { return SearchStrings(p, x) }
diff --git a/contrib/go/_std_1.19/src/sort/slice.go b/contrib/go/_std_1.19/src/sort/slice.go
new file mode 100644
index 0000000000..443182b42e
--- /dev/null
+++ b/contrib/go/_std_1.19/src/sort/slice.go
@@ -0,0 +1,49 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package sort
+
+import "math/bits"
+
+// Slice sorts the slice x given the provided less function.
+// It panics if x is not a slice.
+//
+// The sort is not guaranteed to be stable: equal elements
+// may be reversed from their original order.
+// For a stable sort, use SliceStable.
+//
+// The less function must satisfy the same requirements as
+// the Interface type's Less method.
+func Slice(x any, less func(i, j int) bool) {
+	rv := reflectValueOf(x)
+	swap := reflectSwapper(x)
+	length := rv.Len()
+	limit := bits.Len(uint(length))
+	pdqsort_func(lessSwap{less, swap}, 0, length, limit)
+}
+
+// SliceStable sorts the slice x using the provided less
+// function, keeping equal elements in their original order.
+// It panics if x is not a slice.
+//
+// The less function must satisfy the same requirements as
+// the Interface type's Less method.
+func SliceStable(x any, less func(i, j int) bool) {
+	rv := reflectValueOf(x)
+	swap := reflectSwapper(x)
+	stable_func(lessSwap{less, swap}, rv.Len())
+}
+
+// SliceIsSorted reports whether the slice x is sorted according to the provided less function.
+// It panics if x is not a slice.
+func SliceIsSorted(x any, less func(i, j int) bool) bool {
+	rv := reflectValueOf(x)
+	n := rv.Len()
+	for i := n - 1; i > 0; i-- {
+		if less(i, i-1) {
+			return false
+		}
+	}
+	return true
+}
diff --git a/contrib/go/_std_1.18/src/sort/slice_go113.go b/contrib/go/_std_1.19/src/sort/slice_go113.go
index 53542dbd1a..53542dbd1a 100644
--- a/contrib/go/_std_1.18/src/sort/slice_go113.go
+++ b/contrib/go/_std_1.19/src/sort/slice_go113.go
diff --git a/contrib/go/_std_1.19/src/sort/sort.go b/contrib/go/_std_1.19/src/sort/sort.go
new file mode 100644
index 0000000000..68e2f0d082
--- /dev/null
+++ b/contrib/go/_std_1.19/src/sort/sort.go
@@ -0,0 +1,262 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:generate go run gen_sort_variants.go
+
+// Package sort provides primitives for sorting slices and user-defined collections.
+package sort
+
+import "math/bits"
+
+// An implementation of Interface can be sorted by the routines in this package.
+// The methods refer to elements of the underlying collection by integer index.
+type Interface interface {
+	// Len is the number of elements in the collection.
+	Len() int
+
+	// Less reports whether the element with index i
+	// must sort before the element with index j.
+	//
+	// If both Less(i, j) and Less(j, i) are false,
+	// then the elements at index i and j are considered equal.
+	// Sort may place equal elements in any order in the final result,
+	// while Stable preserves the original input order of equal elements.
+	//
+	// Less must describe a transitive ordering:
+	//  - if both Less(i, j) and Less(j, k) are true, then Less(i, k) must be true as well.
+	//  - if both Less(i, j) and Less(j, k) are false, then Less(i, k) must be false as well.
+	//
+	// Note that floating-point comparison (the < operator on float32 or float64 values)
+	// is not a transitive ordering when not-a-number (NaN) values are involved.
+	// See Float64Slice.Less for a correct implementation for floating-point values.
+	Less(i, j int) bool
+
+	// Swap swaps the elements with indexes i and j.
+	Swap(i, j int)
+}
+
+// Sort sorts data in ascending order as determined by the Less method.
+// It makes one call to data.Len to determine n and O(n*log(n)) calls to
+// data.Less and data.Swap. The sort is not guaranteed to be stable.
+func Sort(data Interface) {
+	n := data.Len()
+	if n <= 1 {
+		return
+	}
+	limit := bits.Len(uint(n))
+	pdqsort(data, 0, n, limit)
+}
+
+type sortedHint int // hint for pdqsort when choosing the pivot
+
+const (
+	unknownHint sortedHint = iota
+	increasingHint
+	decreasingHint
+)
+
+// xorshift paper: https://www.jstatsoft.org/article/view/v008i14/xorshift.pdf
+type xorshift uint64
+
+func (r *xorshift) Next() uint64 {
+	*r ^= *r << 13
+	*r ^= *r >> 17
+	*r ^= *r << 5
+	return uint64(*r)
+}
+
+func nextPowerOfTwo(length int) uint {
+	shift := uint(bits.Len(uint(length)))
+	return uint(1 << shift)
+}
+
+// lessSwap is a pair of Less and Swap function for use with the
+// auto-generated func-optimized variant of sort.go in
+// zfuncversion.go.
+type lessSwap struct {
+	Less func(i, j int) bool
+	Swap func(i, j int)
+}
+
+type reverse struct {
+	// This embedded Interface permits Reverse to use the methods of
+	// another Interface implementation.
+	Interface
+}
+
+// Less returns the opposite of the embedded implementation's Less method.
+func (r reverse) Less(i, j int) bool {
+	return r.Interface.Less(j, i)
+}
+
+// Reverse returns the reverse order for data.
+func Reverse(data Interface) Interface {
+	return &reverse{data}
+}
+
+// IsSorted reports whether data is sorted.
+func IsSorted(data Interface) bool {
+	n := data.Len()
+	for i := n - 1; i > 0; i-- {
+		if data.Less(i, i-1) {
+			return false
+		}
+	}
+	return true
+}
+
+// Convenience types for common cases
+
+// IntSlice attaches the methods of Interface to []int, sorting in increasing order.
+type IntSlice []int
+
+func (x IntSlice) Len() int           { return len(x) }
+func (x IntSlice) Less(i, j int) bool { return x[i] < x[j] }
+func (x IntSlice) Swap(i, j int)      { x[i], x[j] = x[j], x[i] }
+
+// Sort is a convenience method: x.Sort() calls Sort(x).
+func (x IntSlice) Sort() { Sort(x) }
+
+// Float64Slice implements Interface for a []float64, sorting in increasing order,
+// with not-a-number (NaN) values ordered before other values.
+type Float64Slice []float64
+
+func (x Float64Slice) Len() int { return len(x) }
+
+// Less reports whether x[i] should be ordered before x[j], as required by the sort Interface.
+// Note that floating-point comparison by itself is not a transitive relation: it does not
+// report a consistent ordering for not-a-number (NaN) values.
+// This implementation of Less places NaN values before any others, by using:
+//
+//	x[i] < x[j] || (math.IsNaN(x[i]) && !math.IsNaN(x[j]))
+func (x Float64Slice) Less(i, j int) bool { return x[i] < x[j] || (isNaN(x[i]) && !isNaN(x[j])) }
+func (x Float64Slice) Swap(i, j int)      { x[i], x[j] = x[j], x[i] }
+
+// isNaN is a copy of math.IsNaN to avoid a dependency on the math package.
+func isNaN(f float64) bool {
+	return f != f
+}
+
+// Sort is a convenience method: x.Sort() calls Sort(x).
+func (x Float64Slice) Sort() { Sort(x) }
+
+// StringSlice attaches the methods of Interface to []string, sorting in increasing order.
+type StringSlice []string
+
+func (x StringSlice) Len() int           { return len(x) }
+func (x StringSlice) Less(i, j int) bool { return x[i] < x[j] }
+func (x StringSlice) Swap(i, j int)      { x[i], x[j] = x[j], x[i] }
+
+// Sort is a convenience method: x.Sort() calls Sort(x).
+func (x StringSlice) Sort() { Sort(x) }
+
+// Convenience wrappers for common cases
+
+// Ints sorts a slice of ints in increasing order.
+func Ints(x []int) { Sort(IntSlice(x)) }
+
+// Float64s sorts a slice of float64s in increasing order.
+// Not-a-number (NaN) values are ordered before other values.
+func Float64s(x []float64) { Sort(Float64Slice(x)) }
+
+// Strings sorts a slice of strings in increasing order.
+func Strings(x []string) { Sort(StringSlice(x)) }
+
+// IntsAreSorted reports whether the slice x is sorted in increasing order.
+func IntsAreSorted(x []int) bool { return IsSorted(IntSlice(x)) }
+
+// Float64sAreSorted reports whether the slice x is sorted in increasing order,
+// with not-a-number (NaN) values before any other values.
+func Float64sAreSorted(x []float64) bool { return IsSorted(Float64Slice(x)) }
+
+// StringsAreSorted reports whether the slice x is sorted in increasing order.
+func StringsAreSorted(x []string) bool { return IsSorted(StringSlice(x)) }
+
+// Notes on stable sorting:
+// The used algorithms are simple and provable correct on all input and use
+// only logarithmic additional stack space. They perform well if compared
+// experimentally to other stable in-place sorting algorithms.
+//
+// Remarks on other algorithms evaluated:
+//  - GCC's 4.6.3 stable_sort with merge_without_buffer from libstdc++:
+//    Not faster.
+//  - GCC's __rotate for block rotations: Not faster.
+//  - "Practical in-place mergesort" from  Jyrki Katajainen, Tomi A. Pasanen
+//    and Jukka Teuhola; Nordic Journal of Computing 3,1 (1996), 27-40:
+//    The given algorithms are in-place, number of Swap and Assignments
+//    grow as n log n but the algorithm is not stable.
+//  - "Fast Stable In-Place Sorting with O(n) Data Moves" J.I. Munro and
+//    V. Raman in Algorithmica (1996) 16, 115-160:
+//    This algorithm either needs additional 2n bits or works only if there
+//    are enough different elements available to encode some permutations
+//    which have to be undone later (so not stable on any input).
+//  - All the optimal in-place sorting/merging algorithms I found are either
+//    unstable or rely on enough different elements in each step to encode the
+//    performed block rearrangements. See also "In-Place Merging Algorithms",
+//    Denham Coates-Evely, Department of Computer Science, Kings College,
+//    January 2004 and the references in there.
+//  - Often "optimal" algorithms are optimal in the number of assignments
+//    but Interface has only Swap as operation.
+
+// Stable sorts data in ascending order as determined by the Less method,
+// while keeping the original order of equal elements.
+//
+// It makes one call to data.Len to determine n, O(n*log(n)) calls to
+// data.Less and O(n*log(n)*log(n)) calls to data.Swap.
+func Stable(data Interface) {
+	stable(data, data.Len())
+}
+
+/*
+Complexity of Stable Sorting
+
+
+Complexity of block swapping rotation
+
+Each Swap puts one new element into its correct, final position.
+Elements which reach their final position are no longer moved.
+Thus block swapping rotation needs |u|+|v| calls to Swaps.
+This is best possible as each element might need a move.
+
+Pay attention when comparing to other optimal algorithms which
+typically count the number of assignments instead of swaps:
+E.g. the optimal algorithm of Dudzinski and Dydek for in-place
+rotations uses O(u + v + gcd(u,v)) assignments which is
+better than our O(3 * (u+v)) as gcd(u,v) <= u.
+
+
+Stable sorting by SymMerge and BlockSwap rotations
+
+SymMerg complexity for same size input M = N:
+Calls to Less:  O(M*log(N/M+1)) = O(N*log(2)) = O(N)
+Calls to Swap:  O((M+N)*log(M)) = O(2*N*log(N)) = O(N*log(N))
+
+(The following argument does not fuzz over a missing -1 or
+other stuff which does not impact the final result).
+
+Let n = data.Len(). Assume n = 2^k.
+
+Plain merge sort performs log(n) = k iterations.
+On iteration i the algorithm merges 2^(k-i) blocks, each of size 2^i.
+
+Thus iteration i of merge sort performs:
+Calls to Less  O(2^(k-i) * 2^i) = O(2^k) = O(2^log(n)) = O(n)
+Calls to Swap  O(2^(k-i) * 2^i * log(2^i)) = O(2^k * i) = O(n*i)
+
+In total k = log(n) iterations are performed; so in total:
+Calls to Less O(log(n) * n)
+Calls to Swap O(n + 2*n + 3*n + ... + (k-1)*n + k*n)
+   = O((k/2) * k * n) = O(n * k^2) = O(n * log^2(n))
+
+
+Above results should generalize to arbitrary n = 2^k + p
+and should not be influenced by the initial insertion sort phase:
+Insertion sort is O(n^2) on Swap and Less, thus O(bs^2) per block of
+size bs at n/bs blocks:  O(bs*n) Swaps and Less during insertion sort.
+Merge sort iterations start at i = log(bs). With t = log(bs) constant:
+Calls to Less O((log(n)-t) * n + bs*n) = O(log(n)*n + (bs-t)*n)
+   = O(n * log(n))
+Calls to Swap O(n * log^2(n) - (t^2+t)/2*n) = O(n * log^2(n))
+
+*/
diff --git a/contrib/go/_std_1.19/src/sort/zsortfunc.go b/contrib/go/_std_1.19/src/sort/zsortfunc.go
new file mode 100644
index 0000000000..49b6169b97
--- /dev/null
+++ b/contrib/go/_std_1.19/src/sort/zsortfunc.go
@@ -0,0 +1,479 @@
+// Code generated by gen_sort_variants.go; DO NOT EDIT.
+
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package sort
+
+// insertionSort_func sorts data[a:b] using insertion sort.
+func insertionSort_func(data lessSwap, a, b int) {
+	for i := a + 1; i < b; i++ {
+		for j := i; j > a && data.Less(j, j-1); j-- {
+			data.Swap(j, j-1)
+		}
+	}
+}
+
+// siftDown_func implements the heap property on data[lo:hi].
+// first is an offset into the array where the root of the heap lies.
+func siftDown_func(data lessSwap, lo, hi, first int) {
+	root := lo
+	for {
+		child := 2*root + 1
+		if child >= hi {
+			break
+		}
+		if child+1 < hi && data.Less(first+child, first+child+1) {
+			child++
+		}
+		if !data.Less(first+root, first+child) {
+			return
+		}
+		data.Swap(first+root, first+child)
+		root = child
+	}
+}
+
+func heapSort_func(data lessSwap, a, b int) {
+	first := a
+	lo := 0
+	hi := b - a
+
+	// Build heap with greatest element at top.
+	for i := (hi - 1) / 2; i >= 0; i-- {
+		siftDown_func(data, i, hi, first)
+	}
+
+	// Pop elements, largest first, into end of data.
+	for i := hi - 1; i >= 0; i-- {
+		data.Swap(first, first+i)
+		siftDown_func(data, lo, i, first)
+	}
+}
+
+// pdqsort_func sorts data[a:b].
+// The algorithm based on pattern-defeating quicksort(pdqsort), but without the optimizations from BlockQuicksort.
+// pdqsort paper: https://arxiv.org/pdf/2106.05123.pdf
+// C++ implementation: https://github.com/orlp/pdqsort
+// Rust implementation: https://docs.rs/pdqsort/latest/pdqsort/
+// limit is the number of allowed bad (very unbalanced) pivots before falling back to heapsort.
+func pdqsort_func(data lessSwap, a, b, limit int) {
+	const maxInsertion = 12
+
+	var (
+		wasBalanced    = true // whether the last partitioning was reasonably balanced
+		wasPartitioned = true // whether the slice was already partitioned
+	)
+
+	for {
+		length := b - a
+
+		if length <= maxInsertion {
+			insertionSort_func(data, a, b)
+			return
+		}
+
+		// Fall back to heapsort if too many bad choices were made.
+		if limit == 0 {
+			heapSort_func(data, a, b)
+			return
+		}
+
+		// If the last partitioning was imbalanced, we need to breaking patterns.
+		if !wasBalanced {
+			breakPatterns_func(data, a, b)
+			limit--
+		}
+
+		pivot, hint := choosePivot_func(data, a, b)
+		if hint == decreasingHint {
+			reverseRange_func(data, a, b)
+			// The chosen pivot was pivot-a elements after the start of the array.
+			// After reversing it is pivot-a elements before the end of the array.
+			// The idea came from Rust's implementation.
+			pivot = (b - 1) - (pivot - a)
+			hint = increasingHint
+		}
+
+		// The slice is likely already sorted.
+		if wasBalanced && wasPartitioned && hint == increasingHint {
+			if partialInsertionSort_func(data, a, b) {
+				return
+			}
+		}
+
+		// Probably the slice contains many duplicate elements, partition the slice into
+		// elements equal to and elements greater than the pivot.
+		if a > 0 && !data.Less(a-1, pivot) {
+			mid := partitionEqual_func(data, a, b, pivot)
+			a = mid
+			continue
+		}
+
+		mid, alreadyPartitioned := partition_func(data, a, b, pivot)
+		wasPartitioned = alreadyPartitioned
+
+		leftLen, rightLen := mid-a, b-mid
+		balanceThreshold := length / 8
+		if leftLen < rightLen {
+			wasBalanced = leftLen >= balanceThreshold
+			pdqsort_func(data, a, mid, limit)
+			a = mid + 1
+		} else {
+			wasBalanced = rightLen >= balanceThreshold
+			pdqsort_func(data, mid+1, b, limit)
+			b = mid
+		}
+	}
+}
+
+// partition_func does one quicksort partition.
+// Let p = data[pivot]
+// Moves elements in data[a:b] around, so that data[i]<p and data[j]>=p for i<newpivot and j>newpivot.
+// On return, data[newpivot] = p
+func partition_func(data lessSwap, a, b, pivot int) (newpivot int, alreadyPartitioned bool) {
+	data.Swap(a, pivot)
+	i, j := a+1, b-1 // i and j are inclusive of the elements remaining to be partitioned
+
+	for i <= j && data.Less(i, a) {
+		i++
+	}
+	for i <= j && !data.Less(j, a) {
+		j--
+	}
+	if i > j {
+		data.Swap(j, a)
+		return j, true
+	}
+	data.Swap(i, j)
+	i++
+	j--
+
+	for {
+		for i <= j && data.Less(i, a) {
+			i++
+		}
+		for i <= j && !data.Less(j, a) {
+			j--
+		}
+		if i > j {
+			break
+		}
+		data.Swap(i, j)
+		i++
+		j--
+	}
+	data.Swap(j, a)
+	return j, false
+}
+
+// partitionEqual_func partitions data[a:b] into elements equal to data[pivot] followed by elements greater than data[pivot].
+// It assumed that data[a:b] does not contain elements smaller than the data[pivot].
+func partitionEqual_func(data lessSwap, a, b, pivot int) (newpivot int) {
+	data.Swap(a, pivot)
+	i, j := a+1, b-1 // i and j are inclusive of the elements remaining to be partitioned
+
+	for {
+		for i <= j && !data.Less(a, i) {
+			i++
+		}
+		for i <= j && data.Less(a, j) {
+			j--
+		}
+		if i > j {
+			break
+		}
+		data.Swap(i, j)
+		i++
+		j--
+	}
+	return i
+}
+
+// partialInsertionSort_func partially sorts a slice, returns true if the slice is sorted at the end.
+func partialInsertionSort_func(data lessSwap, a, b int) bool {
+	const (
+		maxSteps         = 5  // maximum number of adjacent out-of-order pairs that will get shifted
+		shortestShifting = 50 // don't shift any elements on short arrays
+	)
+	i := a + 1
+	for j := 0; j < maxSteps; j++ {
+		for i < b && !data.Less(i, i-1) {
+			i++
+		}
+
+		if i == b {
+			return true
+		}
+
+		if b-a < shortestShifting {
+			return false
+		}
+
+		data.Swap(i, i-1)
+
+		// Shift the smaller one to the left.
+		if i-a >= 2 {
+			for j := i - 1; j >= 1; j-- {
+				if !data.Less(j, j-1) {
+					break
+				}
+				data.Swap(j, j-1)
+			}
+		}
+		// Shift the greater one to the right.
+		if b-i >= 2 {
+			for j := i + 1; j < b; j++ {
+				if !data.Less(j, j-1) {
+					break
+				}
+				data.Swap(j, j-1)
+			}
+		}
+	}
+	return false
+}
+
+// breakPatterns_func scatters some elements around in an attempt to break some patterns
+// that might cause imbalanced partitions in quicksort.
+func breakPatterns_func(data lessSwap, a, b int) {
+	length := b - a
+	if length >= 8 {
+		random := xorshift(length)
+		modulus := nextPowerOfTwo(length)
+
+		for idx := a + (length/4)*2 - 1; idx <= a+(length/4)*2+1; idx++ {
+			other := int(uint(random.Next()) & (modulus - 1))
+			if other >= length {
+				other -= length
+			}
+			data.Swap(idx, a+other)
+		}
+	}
+}
+
+// choosePivot_func chooses a pivot in data[a:b].
+//
+// [0,8): chooses a static pivot.
+// [8,shortestNinther): uses the simple median-of-three method.
+// [shortestNinther,∞): uses the Tukey ninther method.
+func choosePivot_func(data lessSwap, a, b int) (pivot int, hint sortedHint) {
+	const (
+		shortestNinther = 50
+		maxSwaps        = 4 * 3
+	)
+
+	l := b - a
+
+	var (
+		swaps int
+		i     = a + l/4*1
+		j     = a + l/4*2
+		k     = a + l/4*3
+	)
+
+	if l >= 8 {
+		if l >= shortestNinther {
+			// Tukey ninther method, the idea came from Rust's implementation.
+			i = medianAdjacent_func(data, i, &swaps)
+			j = medianAdjacent_func(data, j, &swaps)
+			k = medianAdjacent_func(data, k, &swaps)
+		}
+		// Find the median among i, j, k and stores it into j.
+		j = median_func(data, i, j, k, &swaps)
+	}
+
+	switch swaps {
+	case 0:
+		return j, increasingHint
+	case maxSwaps:
+		return j, decreasingHint
+	default:
+		return j, unknownHint
+	}
+}
+
+// order2_func returns x,y where data[x] <= data[y], where x,y=a,b or x,y=b,a.
+func order2_func(data lessSwap, a, b int, swaps *int) (int, int) {
+	if data.Less(b, a) {
+		*swaps++
+		return b, a
+	}
+	return a, b
+}
+
+// median_func returns x where data[x] is the median of data[a],data[b],data[c], where x is a, b, or c.
+func median_func(data lessSwap, a, b, c int, swaps *int) int {
+	a, b = order2_func(data, a, b, swaps)
+	b, c = order2_func(data, b, c, swaps)
+	a, b = order2_func(data, a, b, swaps)
+	return b
+}
+
+// medianAdjacent_func finds the median of data[a - 1], data[a], data[a + 1] and stores the index into a.
+func medianAdjacent_func(data lessSwap, a int, swaps *int) int {
+	return median_func(data, a-1, a, a+1, swaps)
+}
+
+func reverseRange_func(data lessSwap, a, b int) {
+	i := a
+	j := b - 1
+	for i < j {
+		data.Swap(i, j)
+		i++
+		j--
+	}
+}
+
+func swapRange_func(data lessSwap, a, b, n int) {
+	for i := 0; i < n; i++ {
+		data.Swap(a+i, b+i)
+	}
+}
+
+func stable_func(data lessSwap, n int) {
+	blockSize := 20 // must be > 0
+	a, b := 0, blockSize
+	for b <= n {
+		insertionSort_func(data, a, b)
+		a = b
+		b += blockSize
+	}
+	insertionSort_func(data, a, n)
+
+	for blockSize < n {
+		a, b = 0, 2*blockSize
+		for b <= n {
+			symMerge_func(data, a, a+blockSize, b)
+			a = b
+			b += 2 * blockSize
+		}
+		if m := a + blockSize; m < n {
+			symMerge_func(data, a, m, n)
+		}
+		blockSize *= 2
+	}
+}
+
+// symMerge_func merges the two sorted subsequences data[a:m] and data[m:b] using
+// the SymMerge algorithm from Pok-Son Kim and Arne Kutzner, "Stable Minimum
+// Storage Merging by Symmetric Comparisons", in Susanne Albers and Tomasz
+// Radzik, editors, Algorithms - ESA 2004, volume 3221 of Lecture Notes in
+// Computer Science, pages 714-723. Springer, 2004.
+//
+// Let M = m-a and N = b-n. Wolog M < N.
+// The recursion depth is bound by ceil(log(N+M)).
+// The algorithm needs O(M*log(N/M + 1)) calls to data.Less.
+// The algorithm needs O((M+N)*log(M)) calls to data.Swap.
+//
+// The paper gives O((M+N)*log(M)) as the number of assignments assuming a
+// rotation algorithm which uses O(M+N+gcd(M+N)) assignments. The argumentation
+// in the paper carries through for Swap operations, especially as the block
+// swapping rotate uses only O(M+N) Swaps.
+//
+// symMerge assumes non-degenerate arguments: a < m && m < b.
+// Having the caller check this condition eliminates many leaf recursion calls,
+// which improves performance.
+func symMerge_func(data lessSwap, a, m, b int) {
+	// Avoid unnecessary recursions of symMerge
+	// by direct insertion of data[a] into data[m:b]
+	// if data[a:m] only contains one element.
+	if m-a == 1 {
+		// Use binary search to find the lowest index i
+		// such that data[i] >= data[a] for m <= i < b.
+		// Exit the search loop with i == b in case no such index exists.
+		i := m
+		j := b
+		for i < j {
+			h := int(uint(i+j) >> 1)
+			if data.Less(h, a) {
+				i = h + 1
+			} else {
+				j = h
+			}
+		}
+		// Swap values until data[a] reaches the position before i.
+		for k := a; k < i-1; k++ {
+			data.Swap(k, k+1)
+		}
+		return
+	}
+
+	// Avoid unnecessary recursions of symMerge
+	// by direct insertion of data[m] into data[a:m]
+	// if data[m:b] only contains one element.
+	if b-m == 1 {
+		// Use binary search to find the lowest index i
+		// such that data[i] > data[m] for a <= i < m.
+		// Exit the search loop with i == m in case no such index exists.
+		i := a
+		j := m
+		for i < j {
+			h := int(uint(i+j) >> 1)
+			if !data.Less(m, h) {
+				i = h + 1
+			} else {
+				j = h
+			}
+		}
+		// Swap values until data[m] reaches the position i.
+		for k := m; k > i; k-- {
+			data.Swap(k, k-1)
+		}
+		return
+	}
+
+	mid := int(uint(a+b) >> 1)
+	n := mid + m
+	var start, r int
+	if m > mid {
+		start = n - b
+		r = mid
+	} else {
+		start = a
+		r = m
+	}
+	p := n - 1
+
+	for start < r {
+		c := int(uint(start+r) >> 1)
+		if !data.Less(p-c, c) {
+			start = c + 1
+		} else {
+			r = c
+		}
+	}
+
+	end := n - start
+	if start < m && m < end {
+		rotate_func(data, start, m, end)
+	}
+	if a < start && start < mid {
+		symMerge_func(data, a, start, mid)
+	}
+	if mid < end && end < b {
+		symMerge_func(data, mid, end, b)
+	}
+}
+
+// rotate_func rotates two consecutive blocks u = data[a:m] and v = data[m:b] in data:
+// Data of the form 'x u v y' is changed to 'x v u y'.
+// rotate performs at most b-a many calls to data.Swap,
+// and it assumes non-degenerate arguments: a < m && m < b.
+func rotate_func(data lessSwap, a, m, b int) {
+	i := m - a
+	j := b - m
+
+	for i != j {
+		if i > j {
+			swapRange_func(data, m-i, m, j)
+			i -= j
+		} else {
+			swapRange_func(data, m-i, m+j-i, i)
+			j -= i
+		}
+	}
+	// i == j
+	swapRange_func(data, m-i, m, i)
+}
diff --git a/contrib/go/_std_1.19/src/sort/zsortinterface.go b/contrib/go/_std_1.19/src/sort/zsortinterface.go
new file mode 100644
index 0000000000..51fa5032e9
--- /dev/null
+++ b/contrib/go/_std_1.19/src/sort/zsortinterface.go
@@ -0,0 +1,479 @@
+// Code generated by gen_sort_variants.go; DO NOT EDIT.
+
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package sort
+
+// insertionSort sorts data[a:b] using insertion sort.
+func insertionSort(data Interface, a, b int) {
+	for i := a + 1; i < b; i++ {
+		for j := i; j > a && data.Less(j, j-1); j-- {
+			data.Swap(j, j-1)
+		}
+	}
+}
+
+// siftDown implements the heap property on data[lo:hi].
+// first is an offset into the array where the root of the heap lies.
+func siftDown(data Interface, lo, hi, first int) {
+	root := lo
+	for {
+		child := 2*root + 1
+		if child >= hi {
+			break
+		}
+		if child+1 < hi && data.Less(first+child, first+child+1) {
+			child++
+		}
+		if !data.Less(first+root, first+child) {
+			return
+		}
+		data.Swap(first+root, first+child)
+		root = child
+	}
+}
+
+func heapSort(data Interface, a, b int) {
+	first := a
+	lo := 0
+	hi := b - a
+
+	// Build heap with greatest element at top.
+	for i := (hi - 1) / 2; i >= 0; i-- {
+		siftDown(data, i, hi, first)
+	}
+
+	// Pop elements, largest first, into end of data.
+	for i := hi - 1; i >= 0; i-- {
+		data.Swap(first, first+i)
+		siftDown(data, lo, i, first)
+	}
+}
+
+// pdqsort sorts data[a:b].
+// The algorithm based on pattern-defeating quicksort(pdqsort), but without the optimizations from BlockQuicksort.
+// pdqsort paper: https://arxiv.org/pdf/2106.05123.pdf
+// C++ implementation: https://github.com/orlp/pdqsort
+// Rust implementation: https://docs.rs/pdqsort/latest/pdqsort/
+// limit is the number of allowed bad (very unbalanced) pivots before falling back to heapsort.
+func pdqsort(data Interface, a, b, limit int) {
+	const maxInsertion = 12
+
+	var (
+		wasBalanced    = true // whether the last partitioning was reasonably balanced
+		wasPartitioned = true // whether the slice was already partitioned
+	)
+
+	for {
+		length := b - a
+
+		if length <= maxInsertion {
+			insertionSort(data, a, b)
+			return
+		}
+
+		// Fall back to heapsort if too many bad choices were made.
+		if limit == 0 {
+			heapSort(data, a, b)
+			return
+		}
+
+		// If the last partitioning was imbalanced, we need to breaking patterns.
+		if !wasBalanced {
+			breakPatterns(data, a, b)
+			limit--
+		}
+
+		pivot, hint := choosePivot(data, a, b)
+		if hint == decreasingHint {
+			reverseRange(data, a, b)
+			// The chosen pivot was pivot-a elements after the start of the array.
+			// After reversing it is pivot-a elements before the end of the array.
+			// The idea came from Rust's implementation.
+			pivot = (b - 1) - (pivot - a)
+			hint = increasingHint
+		}
+
+		// The slice is likely already sorted.
+		if wasBalanced && wasPartitioned && hint == increasingHint {
+			if partialInsertionSort(data, a, b) {
+				return
+			}
+		}
+
+		// Probably the slice contains many duplicate elements, partition the slice into
+		// elements equal to and elements greater than the pivot.
+		if a > 0 && !data.Less(a-1, pivot) {
+			mid := partitionEqual(data, a, b, pivot)
+			a = mid
+			continue
+		}
+
+		mid, alreadyPartitioned := partition(data, a, b, pivot)
+		wasPartitioned = alreadyPartitioned
+
+		leftLen, rightLen := mid-a, b-mid
+		balanceThreshold := length / 8
+		if leftLen < rightLen {
+			wasBalanced = leftLen >= balanceThreshold
+			pdqsort(data, a, mid, limit)
+			a = mid + 1
+		} else {
+			wasBalanced = rightLen >= balanceThreshold
+			pdqsort(data, mid+1, b, limit)
+			b = mid
+		}
+	}
+}
+
+// partition does one quicksort partition.
+// Let p = data[pivot]
+// Moves elements in data[a:b] around, so that data[i]<p and data[j]>=p for i<newpivot and j>newpivot.
+// On return, data[newpivot] = p
+func partition(data Interface, a, b, pivot int) (newpivot int, alreadyPartitioned bool) {
+	data.Swap(a, pivot)
+	i, j := a+1, b-1 // i and j are inclusive of the elements remaining to be partitioned
+
+	for i <= j && data.Less(i, a) {
+		i++
+	}
+	for i <= j && !data.Less(j, a) {
+		j--
+	}
+	if i > j {
+		data.Swap(j, a)
+		return j, true
+	}
+	data.Swap(i, j)
+	i++
+	j--
+
+	for {
+		for i <= j && data.Less(i, a) {
+			i++
+		}
+		for i <= j && !data.Less(j, a) {
+			j--
+		}
+		if i > j {
+			break
+		}
+		data.Swap(i, j)
+		i++
+		j--
+	}
+	data.Swap(j, a)
+	return j, false
+}
+
+// partitionEqual partitions data[a:b] into elements equal to data[pivot] followed by elements greater than data[pivot].
+// It assumed that data[a:b] does not contain elements smaller than the data[pivot].
+func partitionEqual(data Interface, a, b, pivot int) (newpivot int) {
+	data.Swap(a, pivot)
+	i, j := a+1, b-1 // i and j are inclusive of the elements remaining to be partitioned
+
+	for {
+		for i <= j && !data.Less(a, i) {
+			i++
+		}
+		for i <= j && data.Less(a, j) {
+			j--
+		}
+		if i > j {
+			break
+		}
+		data.Swap(i, j)
+		i++
+		j--
+	}
+	return i
+}
+
+// partialInsertionSort partially sorts a slice, returns true if the slice is sorted at the end.
+func partialInsertionSort(data Interface, a, b int) bool {
+	const (
+		maxSteps         = 5  // maximum number of adjacent out-of-order pairs that will get shifted
+		shortestShifting = 50 // don't shift any elements on short arrays
+	)
+	i := a + 1
+	for j := 0; j < maxSteps; j++ {
+		for i < b && !data.Less(i, i-1) {
+			i++
+		}
+
+		if i == b {
+			return true
+		}
+
+		if b-a < shortestShifting {
+			return false
+		}
+
+		data.Swap(i, i-1)
+
+		// Shift the smaller one to the left.
+		if i-a >= 2 {
+			for j := i - 1; j >= 1; j-- {
+				if !data.Less(j, j-1) {
+					break
+				}
+				data.Swap(j, j-1)
+			}
+		}
+		// Shift the greater one to the right.
+		if b-i >= 2 {
+			for j := i + 1; j < b; j++ {
+				if !data.Less(j, j-1) {
+					break
+				}
+				data.Swap(j, j-1)
+			}
+		}
+	}
+	return false
+}
+
+// breakPatterns scatters some elements around in an attempt to break some patterns
+// that might cause imbalanced partitions in quicksort.
+func breakPatterns(data Interface, a, b int) {
+	length := b - a
+	if length >= 8 {
+		random := xorshift(length)
+		modulus := nextPowerOfTwo(length)
+
+		for idx := a + (length/4)*2 - 1; idx <= a+(length/4)*2+1; idx++ {
+			other := int(uint(random.Next()) & (modulus - 1))
+			if other >= length {
+				other -= length
+			}
+			data.Swap(idx, a+other)
+		}
+	}
+}
+
+// choosePivot chooses a pivot in data[a:b].
+//
+// [0,8): chooses a static pivot.
+// [8,shortestNinther): uses the simple median-of-three method.
+// [shortestNinther,∞): uses the Tukey ninther method.
+func choosePivot(data Interface, a, b int) (pivot int, hint sortedHint) {
+	const (
+		shortestNinther = 50
+		maxSwaps        = 4 * 3
+	)
+
+	l := b - a
+
+	var (
+		swaps int
+		i     = a + l/4*1
+		j     = a + l/4*2
+		k     = a + l/4*3
+	)
+
+	if l >= 8 {
+		if l >= shortestNinther {
+			// Tukey ninther method, the idea came from Rust's implementation.
+			i = medianAdjacent(data, i, &swaps)
+			j = medianAdjacent(data, j, &swaps)
+			k = medianAdjacent(data, k, &swaps)
+		}
+		// Find the median among i, j, k and stores it into j.
+		j = median(data, i, j, k, &swaps)
+	}
+
+	switch swaps {
+	case 0:
+		return j, increasingHint
+	case maxSwaps:
+		return j, decreasingHint
+	default:
+		return j, unknownHint
+	}
+}
+
+// order2 returns x,y where data[x] <= data[y], where x,y=a,b or x,y=b,a.
+func order2(data Interface, a, b int, swaps *int) (int, int) {
+	if data.Less(b, a) {
+		*swaps++
+		return b, a
+	}
+	return a, b
+}
+
+// median returns x where data[x] is the median of data[a],data[b],data[c], where x is a, b, or c.
+func median(data Interface, a, b, c int, swaps *int) int {
+	a, b = order2(data, a, b, swaps)
+	b, c = order2(data, b, c, swaps)
+	a, b = order2(data, a, b, swaps)
+	return b
+}
+
+// medianAdjacent finds the median of data[a - 1], data[a], data[a + 1] and stores the index into a.
+func medianAdjacent(data Interface, a int, swaps *int) int {
+	return median(data, a-1, a, a+1, swaps)
+}
+
+func reverseRange(data Interface, a, b int) {
+	i := a
+	j := b - 1
+	for i < j {
+		data.Swap(i, j)
+		i++
+		j--
+	}
+}
+
+func swapRange(data Interface, a, b, n int) {
+	for i := 0; i < n; i++ {
+		data.Swap(a+i, b+i)
+	}
+}
+
+func stable(data Interface, n int) {
+	blockSize := 20 // must be > 0
+	a, b := 0, blockSize
+	for b <= n {
+		insertionSort(data, a, b)
+		a = b
+		b += blockSize
+	}
+	insertionSort(data, a, n)
+
+	for blockSize < n {
+		a, b = 0, 2*blockSize
+		for b <= n {
+			symMerge(data, a, a+blockSize, b)
+			a = b
+			b += 2 * blockSize
+		}
+		if m := a + blockSize; m < n {
+			symMerge(data, a, m, n)
+		}
+		blockSize *= 2
+	}
+}
+
+// symMerge merges the two sorted subsequences data[a:m] and data[m:b] using
+// the SymMerge algorithm from Pok-Son Kim and Arne Kutzner, "Stable Minimum
+// Storage Merging by Symmetric Comparisons", in Susanne Albers and Tomasz
+// Radzik, editors, Algorithms - ESA 2004, volume 3221 of Lecture Notes in
+// Computer Science, pages 714-723. Springer, 2004.
+//
+// Let M = m-a and N = b-n. Wolog M < N.
+// The recursion depth is bound by ceil(log(N+M)).
+// The algorithm needs O(M*log(N/M + 1)) calls to data.Less.
+// The algorithm needs O((M+N)*log(M)) calls to data.Swap.
+//
+// The paper gives O((M+N)*log(M)) as the number of assignments assuming a
+// rotation algorithm which uses O(M+N+gcd(M+N)) assignments. The argumentation
+// in the paper carries through for Swap operations, especially as the block
+// swapping rotate uses only O(M+N) Swaps.
+//
+// symMerge assumes non-degenerate arguments: a < m && m < b.
+// Having the caller check this condition eliminates many leaf recursion calls,
+// which improves performance.
+func symMerge(data Interface, a, m, b int) {
+	// Avoid unnecessary recursions of symMerge
+	// by direct insertion of data[a] into data[m:b]
+	// if data[a:m] only contains one element.
+	if m-a == 1 {
+		// Use binary search to find the lowest index i
+		// such that data[i] >= data[a] for m <= i < b.
+		// Exit the search loop with i == b in case no such index exists.
+		i := m
+		j := b
+		for i < j {
+			h := int(uint(i+j) >> 1)
+			if data.Less(h, a) {
+				i = h + 1
+			} else {
+				j = h
+			}
+		}
+		// Swap values until data[a] reaches the position before i.
+		for k := a; k < i-1; k++ {
+			data.Swap(k, k+1)
+		}
+		return
+	}
+
+	// Avoid unnecessary recursions of symMerge
+	// by direct insertion of data[m] into data[a:m]
+	// if data[m:b] only contains one element.
+	if b-m == 1 {
+		// Use binary search to find the lowest index i
+		// such that data[i] > data[m] for a <= i < m.
+		// Exit the search loop with i == m in case no such index exists.
+		i := a
+		j := m
+		for i < j {
+			h := int(uint(i+j) >> 1)
+			if !data.Less(m, h) {
+				i = h + 1
+			} else {
+				j = h
+			}
+		}
+		// Swap values until data[m] reaches the position i.
+		for k := m; k > i; k-- {
+			data.Swap(k, k-1)
+		}
+		return
+	}
+
+	mid := int(uint(a+b) >> 1)
+	n := mid + m
+	var start, r int
+	if m > mid {
+		start = n - b
+		r = mid
+	} else {
+		start = a
+		r = m
+	}
+	p := n - 1
+
+	for start < r {
+		c := int(uint(start+r) >> 1)
+		if !data.Less(p-c, c) {
+			start = c + 1
+		} else {
+			r = c
+		}
+	}
+
+	end := n - start
+	if start < m && m < end {
+		rotate(data, start, m, end)
+	}
+	if a < start && start < mid {
+		symMerge(data, a, start, mid)
+	}
+	if mid < end && end < b {
+		symMerge(data, mid, end, b)
+	}
+}
+
+// rotate rotates two consecutive blocks u = data[a:m] and v = data[m:b] in data:
+// Data of the form 'x u v y' is changed to 'x v u y'.
+// rotate performs at most b-a many calls to data.Swap,
+// and it assumes non-degenerate arguments: a < m && m < b.
+func rotate(data Interface, a, m, b int) {
+	i := m - a
+	j := b - m
+
+	for i != j {
+		if i > j {
+			swapRange(data, m-i, m, j)
+			i -= j
+		} else {
+			swapRange(data, m-i, m+j-i, i)
+			j -= i
+		}
+	}
+	// i == j
+	swapRange(data, m-i, m, i)
+}
diff --git a/contrib/go/_std_1.18/src/strconv/atob.go b/contrib/go/_std_1.19/src/strconv/atob.go
index 0a495008d7..0a495008d7 100644
--- a/contrib/go/_std_1.18/src/strconv/atob.go
+++ b/contrib/go/_std_1.19/src/strconv/atob.go
diff --git a/contrib/go/_std_1.18/src/strconv/atoc.go b/contrib/go/_std_1.19/src/strconv/atoc.go
index 85c7bafefa..85c7bafefa 100644
--- a/contrib/go/_std_1.18/src/strconv/atoc.go
+++ b/contrib/go/_std_1.19/src/strconv/atoc.go
diff --git a/contrib/go/_std_1.19/src/strconv/atof.go b/contrib/go/_std_1.19/src/strconv/atof.go
new file mode 100644
index 0000000000..8fc90425f6
--- /dev/null
+++ b/contrib/go/_std_1.19/src/strconv/atof.go
@@ -0,0 +1,709 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package strconv
+
+// decimal to binary floating point conversion.
+// Algorithm:
+//   1) Store input in multiprecision decimal.
+//   2) Multiply/divide decimal by powers of two until in range [0.5, 1)
+//   3) Multiply by 2^precision and round to get mantissa.
+
+import "math"
+
+var optimize = true // set to false to force slow-path conversions for testing
+
+// commonPrefixLenIgnoreCase returns the length of the common
+// prefix of s and prefix, with the character case of s ignored.
+// The prefix argument must be all lower-case.
+func commonPrefixLenIgnoreCase(s, prefix string) int {
+	n := len(prefix)
+	if n > len(s) {
+		n = len(s)
+	}
+	for i := 0; i < n; i++ {
+		c := s[i]
+		if 'A' <= c && c <= 'Z' {
+			c += 'a' - 'A'
+		}
+		if c != prefix[i] {
+			return i
+		}
+	}
+	return n
+}
+
+// special returns the floating-point value for the special,
+// possibly signed floating-point representations inf, infinity,
+// and NaN. The result is ok if a prefix of s contains one
+// of these representations and n is the length of that prefix.
+// The character case is ignored.
+func special(s string) (f float64, n int, ok bool) {
+	if len(s) == 0 {
+		return 0, 0, false
+	}
+	sign := 1
+	nsign := 0
+	switch s[0] {
+	case '+', '-':
+		if s[0] == '-' {
+			sign = -1
+		}
+		nsign = 1
+		s = s[1:]
+		fallthrough
+	case 'i', 'I':
+		n := commonPrefixLenIgnoreCase(s, "infinity")
+		// Anything longer than "inf" is ok, but if we
+		// don't have "infinity", only consume "inf".
+		if 3 < n && n < 8 {
+			n = 3
+		}
+		if n == 3 || n == 8 {
+			return math.Inf(sign), nsign + n, true
+		}
+	case 'n', 'N':
+		if commonPrefixLenIgnoreCase(s, "nan") == 3 {
+			return math.NaN(), 3, true
+		}
+	}
+	return 0, 0, false
+}
+
+func (b *decimal) set(s string) (ok bool) {
+	i := 0
+	b.neg = false
+	b.trunc = false
+
+	// optional sign
+	if i >= len(s) {
+		return
+	}
+	switch {
+	case s[i] == '+':
+		i++
+	case s[i] == '-':
+		b.neg = true
+		i++
+	}
+
+	// digits
+	sawdot := false
+	sawdigits := false
+	for ; i < len(s); i++ {
+		switch {
+		case s[i] == '_':
+			// readFloat already checked underscores
+			continue
+		case s[i] == '.':
+			if sawdot {
+				return
+			}
+			sawdot = true
+			b.dp = b.nd
+			continue
+
+		case '0' <= s[i] && s[i] <= '9':
+			sawdigits = true
+			if s[i] == '0' && b.nd == 0 { // ignore leading zeros
+				b.dp--
+				continue
+			}
+			if b.nd < len(b.d) {
+				b.d[b.nd] = s[i]
+				b.nd++
+			} else if s[i] != '0' {
+				b.trunc = true
+			}
+			continue
+		}
+		break
+	}
+	if !sawdigits {
+		return
+	}
+	if !sawdot {
+		b.dp = b.nd
+	}
+
+	// optional exponent moves decimal point.
+	// if we read a very large, very long number,
+	// just be sure to move the decimal point by
+	// a lot (say, 100000).  it doesn't matter if it's
+	// not the exact number.
+	if i < len(s) && lower(s[i]) == 'e' {
+		i++
+		if i >= len(s) {
+			return
+		}
+		esign := 1
+		if s[i] == '+' {
+			i++
+		} else if s[i] == '-' {
+			i++
+			esign = -1
+		}
+		if i >= len(s) || s[i] < '0' || s[i] > '9' {
+			return
+		}
+		e := 0
+		for ; i < len(s) && ('0' <= s[i] && s[i] <= '9' || s[i] == '_'); i++ {
+			if s[i] == '_' {
+				// readFloat already checked underscores
+				continue
+			}
+			if e < 10000 {
+				e = e*10 + int(s[i]) - '0'
+			}
+		}
+		b.dp += e * esign
+	}
+
+	if i != len(s) {
+		return
+	}
+
+	ok = true
+	return
+}
+
+// readFloat reads a decimal or hexadecimal mantissa and exponent from a float
+// string representation in s; the number may be followed by other characters.
+// readFloat reports the number of bytes consumed (i), and whether the number
+// is valid (ok).
+func readFloat(s string) (mantissa uint64, exp int, neg, trunc, hex bool, i int, ok bool) {
+	underscores := false
+
+	// optional sign
+	if i >= len(s) {
+		return
+	}
+	switch {
+	case s[i] == '+':
+		i++
+	case s[i] == '-':
+		neg = true
+		i++
+	}
+
+	// digits
+	base := uint64(10)
+	maxMantDigits := 19 // 10^19 fits in uint64
+	expChar := byte('e')
+	if i+2 < len(s) && s[i] == '0' && lower(s[i+1]) == 'x' {
+		base = 16
+		maxMantDigits = 16 // 16^16 fits in uint64
+		i += 2
+		expChar = 'p'
+		hex = true
+	}
+	sawdot := false
+	sawdigits := false
+	nd := 0
+	ndMant := 0
+	dp := 0
+loop:
+	for ; i < len(s); i++ {
+		switch c := s[i]; true {
+		case c == '_':
+			underscores = true
+			continue
+
+		case c == '.':
+			if sawdot {
+				break loop
+			}
+			sawdot = true
+			dp = nd
+			continue
+
+		case '0' <= c && c <= '9':
+			sawdigits = true
+			if c == '0' && nd == 0 { // ignore leading zeros
+				dp--
+				continue
+			}
+			nd++
+			if ndMant < maxMantDigits {
+				mantissa *= base
+				mantissa += uint64(c - '0')
+				ndMant++
+			} else if c != '0' {
+				trunc = true
+			}
+			continue
+
+		case base == 16 && 'a' <= lower(c) && lower(c) <= 'f':
+			sawdigits = true
+			nd++
+			if ndMant < maxMantDigits {
+				mantissa *= 16
+				mantissa += uint64(lower(c) - 'a' + 10)
+				ndMant++
+			} else {
+				trunc = true
+			}
+			continue
+		}
+		break
+	}
+	if !sawdigits {
+		return
+	}
+	if !sawdot {
+		dp = nd
+	}
+
+	if base == 16 {
+		dp *= 4
+		ndMant *= 4
+	}
+
+	// optional exponent moves decimal point.
+	// if we read a very large, very long number,
+	// just be sure to move the decimal point by
+	// a lot (say, 100000).  it doesn't matter if it's
+	// not the exact number.
+	if i < len(s) && lower(s[i]) == expChar {
+		i++
+		if i >= len(s) {
+			return
+		}
+		esign := 1
+		if s[i] == '+' {
+			i++
+		} else if s[i] == '-' {
+			i++
+			esign = -1
+		}
+		if i >= len(s) || s[i] < '0' || s[i] > '9' {
+			return
+		}
+		e := 0
+		for ; i < len(s) && ('0' <= s[i] && s[i] <= '9' || s[i] == '_'); i++ {
+			if s[i] == '_' {
+				underscores = true
+				continue
+			}
+			if e < 10000 {
+				e = e*10 + int(s[i]) - '0'
+			}
+		}
+		dp += e * esign
+	} else if base == 16 {
+		// Must have exponent.
+		return
+	}
+
+	if mantissa != 0 {
+		exp = dp - ndMant
+	}
+
+	if underscores && !underscoreOK(s[:i]) {
+		return
+	}
+
+	ok = true
+	return
+}
+
+// decimal power of ten to binary power of two.
+var powtab = []int{1, 3, 6, 9, 13, 16, 19, 23, 26}
+
+func (d *decimal) floatBits(flt *floatInfo) (b uint64, overflow bool) {
+	var exp int
+	var mant uint64
+
+	// Zero is always a special case.
+	if d.nd == 0 {
+		mant = 0
+		exp = flt.bias
+		goto out
+	}
+
+	// Obvious overflow/underflow.
+	// These bounds are for 64-bit floats.
+	// Will have to change if we want to support 80-bit floats in the future.
+	if d.dp > 310 {
+		goto overflow
+	}
+	if d.dp < -330 {
+		// zero
+		mant = 0
+		exp = flt.bias
+		goto out
+	}
+
+	// Scale by powers of two until in range [0.5, 1.0)
+	exp = 0
+	for d.dp > 0 {
+		var n int
+		if d.dp >= len(powtab) {
+			n = 27
+		} else {
+			n = powtab[d.dp]
+		}
+		d.Shift(-n)
+		exp += n
+	}
+	for d.dp < 0 || d.dp == 0 && d.d[0] < '5' {
+		var n int
+		if -d.dp >= len(powtab) {
+			n = 27
+		} else {
+			n = powtab[-d.dp]
+		}
+		d.Shift(n)
+		exp -= n
+	}
+
+	// Our range is [0.5,1) but floating point range is [1,2).
+	exp--
+
+	// Minimum representable exponent is flt.bias+1.
+	// If the exponent is smaller, move it up and
+	// adjust d accordingly.
+	if exp < flt.bias+1 {
+		n := flt.bias + 1 - exp
+		d.Shift(-n)
+		exp += n
+	}
+
+	if exp-flt.bias >= 1<<flt.expbits-1 {
+		goto overflow
+	}
+
+	// Extract 1+flt.mantbits bits.
+	d.Shift(int(1 + flt.mantbits))
+	mant = d.RoundedInteger()
+
+	// Rounding might have added a bit; shift down.
+	if mant == 2<<flt.mantbits {
+		mant >>= 1
+		exp++
+		if exp-flt.bias >= 1<<flt.expbits-1 {
+			goto overflow
+		}
+	}
+
+	// Denormalized?
+	if mant&(1<<flt.mantbits) == 0 {
+		exp = flt.bias
+	}
+	goto out
+
+overflow:
+	// ±Inf
+	mant = 0
+	exp = 1<<flt.expbits - 1 + flt.bias
+	overflow = true
+
+out:
+	// Assemble bits.
+	bits := mant & (uint64(1)<<flt.mantbits - 1)
+	bits |= uint64((exp-flt.bias)&(1<<flt.expbits-1)) << flt.mantbits
+	if d.neg {
+		bits |= 1 << flt.mantbits << flt.expbits
+	}
+	return bits, overflow
+}
+
+// Exact powers of 10.
+var float64pow10 = []float64{
+	1e0, 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9,
+	1e10, 1e11, 1e12, 1e13, 1e14, 1e15, 1e16, 1e17, 1e18, 1e19,
+	1e20, 1e21, 1e22,
+}
+var float32pow10 = []float32{1e0, 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9, 1e10}
+
+// If possible to convert decimal representation to 64-bit float f exactly,
+// entirely in floating-point math, do so, avoiding the expense of decimalToFloatBits.
+// Three common cases:
+//
+//	value is exact integer
+//	value is exact integer * exact power of ten
+//	value is exact integer / exact power of ten
+//
+// These all produce potentially inexact but correctly rounded answers.
+func atof64exact(mantissa uint64, exp int, neg bool) (f float64, ok bool) {
+	if mantissa>>float64info.mantbits != 0 {
+		return
+	}
+	f = float64(mantissa)
+	if neg {
+		f = -f
+	}
+	switch {
+	case exp == 0:
+		// an integer.
+		return f, true
+	// Exact integers are <= 10^15.
+	// Exact powers of ten are <= 10^22.
+	case exp > 0 && exp <= 15+22: // int * 10^k
+		// If exponent is big but number of digits is not,
+		// can move a few zeros into the integer part.
+		if exp > 22 {
+			f *= float64pow10[exp-22]
+			exp = 22
+		}
+		if f > 1e15 || f < -1e15 {
+			// the exponent was really too large.
+			return
+		}
+		return f * float64pow10[exp], true
+	case exp < 0 && exp >= -22: // int / 10^k
+		return f / float64pow10[-exp], true
+	}
+	return
+}
+
+// If possible to compute mantissa*10^exp to 32-bit float f exactly,
+// entirely in floating-point math, do so, avoiding the machinery above.
+func atof32exact(mantissa uint64, exp int, neg bool) (f float32, ok bool) {
+	if mantissa>>float32info.mantbits != 0 {
+		return
+	}
+	f = float32(mantissa)
+	if neg {
+		f = -f
+	}
+	switch {
+	case exp == 0:
+		return f, true
+	// Exact integers are <= 10^7.
+	// Exact powers of ten are <= 10^10.
+	case exp > 0 && exp <= 7+10: // int * 10^k
+		// If exponent is big but number of digits is not,
+		// can move a few zeros into the integer part.
+		if exp > 10 {
+			f *= float32pow10[exp-10]
+			exp = 10
+		}
+		if f > 1e7 || f < -1e7 {
+			// the exponent was really too large.
+			return
+		}
+		return f * float32pow10[exp], true
+	case exp < 0 && exp >= -10: // int / 10^k
+		return f / float32pow10[-exp], true
+	}
+	return
+}
+
+// atofHex converts the hex floating-point string s
+// to a rounded float32 or float64 value (depending on flt==&float32info or flt==&float64info)
+// and returns it as a float64.
+// The string s has already been parsed into a mantissa, exponent, and sign (neg==true for negative).
+// If trunc is true, trailing non-zero bits have been omitted from the mantissa.
+func atofHex(s string, flt *floatInfo, mantissa uint64, exp int, neg, trunc bool) (float64, error) {
+	maxExp := 1<<flt.expbits + flt.bias - 2
+	minExp := flt.bias + 1
+	exp += int(flt.mantbits) // mantissa now implicitly divided by 2^mantbits.
+
+	// Shift mantissa and exponent to bring representation into float range.
+	// Eventually we want a mantissa with a leading 1-bit followed by mantbits other bits.
+	// For rounding, we need two more, where the bottom bit represents
+	// whether that bit or any later bit was non-zero.
+	// (If the mantissa has already lost non-zero bits, trunc is true,
+	// and we OR in a 1 below after shifting left appropriately.)
+	for mantissa != 0 && mantissa>>(flt.mantbits+2) == 0 {
+		mantissa <<= 1
+		exp--
+	}
+	if trunc {
+		mantissa |= 1
+	}
+	for mantissa>>(1+flt.mantbits+2) != 0 {
+		mantissa = mantissa>>1 | mantissa&1
+		exp++
+	}
+
+	// If exponent is too negative,
+	// denormalize in hopes of making it representable.
+	// (The -2 is for the rounding bits.)
+	for mantissa > 1 && exp < minExp-2 {
+		mantissa = mantissa>>1 | mantissa&1
+		exp++
+	}
+
+	// Round using two bottom bits.
+	round := mantissa & 3
+	mantissa >>= 2
+	round |= mantissa & 1 // round to even (round up if mantissa is odd)
+	exp += 2
+	if round == 3 {
+		mantissa++
+		if mantissa == 1<<(1+flt.mantbits) {
+			mantissa >>= 1
+			exp++
+		}
+	}
+
+	if mantissa>>flt.mantbits == 0 { // Denormal or zero.
+		exp = flt.bias
+	}
+	var err error
+	if exp > maxExp { // infinity and range error
+		mantissa = 1 << flt.mantbits
+		exp = maxExp + 1
+		err = rangeError(fnParseFloat, s)
+	}
+
+	bits := mantissa & (1<<flt.mantbits - 1)
+	bits |= uint64((exp-flt.bias)&(1<<flt.expbits-1)) << flt.mantbits
+	if neg {
+		bits |= 1 << flt.mantbits << flt.expbits
+	}
+	if flt == &float32info {
+		return float64(math.Float32frombits(uint32(bits))), err
+	}
+	return math.Float64frombits(bits), err
+}
+
+const fnParseFloat = "ParseFloat"
+
+func atof32(s string) (f float32, n int, err error) {
+	if val, n, ok := special(s); ok {
+		return float32(val), n, nil
+	}
+
+	mantissa, exp, neg, trunc, hex, n, ok := readFloat(s)
+	if !ok {
+		return 0, n, syntaxError(fnParseFloat, s)
+	}
+
+	if hex {
+		f, err := atofHex(s[:n], &float32info, mantissa, exp, neg, trunc)
+		return float32(f), n, err
+	}
+
+	if optimize {
+		// Try pure floating-point arithmetic conversion, and if that fails,
+		// the Eisel-Lemire algorithm.
+		if !trunc {
+			if f, ok := atof32exact(mantissa, exp, neg); ok {
+				return f, n, nil
+			}
+		}
+		f, ok := eiselLemire32(mantissa, exp, neg)
+		if ok {
+			if !trunc {
+				return f, n, nil
+			}
+			// Even if the mantissa was truncated, we may
+			// have found the correct result. Confirm by
+			// converting the upper mantissa bound.
+			fUp, ok := eiselLemire32(mantissa+1, exp, neg)
+			if ok && f == fUp {
+				return f, n, nil
+			}
+		}
+	}
+
+	// Slow fallback.
+	var d decimal
+	if !d.set(s[:n]) {
+		return 0, n, syntaxError(fnParseFloat, s)
+	}
+	b, ovf := d.floatBits(&float32info)
+	f = math.Float32frombits(uint32(b))
+	if ovf {
+		err = rangeError(fnParseFloat, s)
+	}
+	return f, n, err
+}
+
+func atof64(s string) (f float64, n int, err error) {
+	if val, n, ok := special(s); ok {
+		return val, n, nil
+	}
+
+	mantissa, exp, neg, trunc, hex, n, ok := readFloat(s)
+	if !ok {
+		return 0, n, syntaxError(fnParseFloat, s)
+	}
+
+	if hex {
+		f, err := atofHex(s[:n], &float64info, mantissa, exp, neg, trunc)
+		return f, n, err
+	}
+
+	if optimize {
+		// Try pure floating-point arithmetic conversion, and if that fails,
+		// the Eisel-Lemire algorithm.
+		if !trunc {
+			if f, ok := atof64exact(mantissa, exp, neg); ok {
+				return f, n, nil
+			}
+		}
+		f, ok := eiselLemire64(mantissa, exp, neg)
+		if ok {
+			if !trunc {
+				return f, n, nil
+			}
+			// Even if the mantissa was truncated, we may
+			// have found the correct result. Confirm by
+			// converting the upper mantissa bound.
+			fUp, ok := eiselLemire64(mantissa+1, exp, neg)
+			if ok && f == fUp {
+				return f, n, nil
+			}
+		}
+	}
+
+	// Slow fallback.
+	var d decimal
+	if !d.set(s[:n]) {
+		return 0, n, syntaxError(fnParseFloat, s)
+	}
+	b, ovf := d.floatBits(&float64info)
+	f = math.Float64frombits(b)
+	if ovf {
+		err = rangeError(fnParseFloat, s)
+	}
+	return f, n, err
+}
+
+// ParseFloat converts the string s to a floating-point number
+// with the precision specified by bitSize: 32 for float32, or 64 for float64.
+// When bitSize=32, the result still has type float64, but it will be
+// convertible to float32 without changing its value.
+//
+// ParseFloat accepts decimal and hexadecimal floating-point numbers
+// as defined by the Go syntax for [floating-point literals].
+// If s is well-formed and near a valid floating-point number,
+// ParseFloat returns the nearest floating-point number rounded
+// using IEEE754 unbiased rounding.
+// (Parsing a hexadecimal floating-point value only rounds when
+// there are more bits in the hexadecimal representation than
+// will fit in the mantissa.)
+//
+// The errors that ParseFloat returns have concrete type *NumError
+// and include err.Num = s.
+//
+// If s is not syntactically well-formed, ParseFloat returns err.Err = ErrSyntax.
+//
+// If s is syntactically well-formed but is more than 1/2 ULP
+// away from the largest floating point number of the given size,
+// ParseFloat returns f = ±Inf, err.Err = ErrRange.
+//
+// ParseFloat recognizes the string "NaN", and the (possibly signed) strings "Inf" and "Infinity"
+// as their respective special floating point values. It ignores case when matching.
+//
+// [floating-point literals]: https://go.dev/ref/spec#Floating-point_literals
+func ParseFloat(s string, bitSize int) (float64, error) {
+	f, n, err := parseFloatPrefix(s, bitSize)
+	if n != len(s) && (err == nil || err.(*NumError).Err != ErrSyntax) {
+		return 0, syntaxError(fnParseFloat, s)
+	}
+	return f, err
+}
+
+func parseFloatPrefix(s string, bitSize int) (float64, int, error) {
+	if bitSize == 32 {
+		f, n, err := atof32(s)
+		return float64(f), n, err
+	}
+	return atof64(s)
+}
diff --git a/contrib/go/_std_1.19/src/strconv/atoi.go b/contrib/go/_std_1.19/src/strconv/atoi.go
new file mode 100644
index 0000000000..be08f93356
--- /dev/null
+++ b/contrib/go/_std_1.19/src/strconv/atoi.go
@@ -0,0 +1,316 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package strconv
+
+import "errors"
+
+// lower(c) is a lower-case letter if and only if
+// c is either that lower-case letter or the equivalent upper-case letter.
+// Instead of writing c == 'x' || c == 'X' one can write lower(c) == 'x'.
+// Note that lower of non-letters can produce other non-letters.
+func lower(c byte) byte {
+	return c | ('x' - 'X')
+}
+
+// ErrRange indicates that a value is out of range for the target type.
+var ErrRange = errors.New("value out of range")
+
+// ErrSyntax indicates that a value does not have the right syntax for the target type.
+var ErrSyntax = errors.New("invalid syntax")
+
+// A NumError records a failed conversion.
+type NumError struct {
+	Func string // the failing function (ParseBool, ParseInt, ParseUint, ParseFloat, ParseComplex)
+	Num  string // the input
+	Err  error  // the reason the conversion failed (e.g. ErrRange, ErrSyntax, etc.)
+}
+
+func (e *NumError) Error() string {
+	return "strconv." + e.Func + ": " + "parsing " + Quote(e.Num) + ": " + e.Err.Error()
+}
+
+func (e *NumError) Unwrap() error { return e.Err }
+
+func syntaxError(fn, str string) *NumError {
+	return &NumError{fn, str, ErrSyntax}
+}
+
+func rangeError(fn, str string) *NumError {
+	return &NumError{fn, str, ErrRange}
+}
+
+func baseError(fn, str string, base int) *NumError {
+	return &NumError{fn, str, errors.New("invalid base " + Itoa(base))}
+}
+
+func bitSizeError(fn, str string, bitSize int) *NumError {
+	return &NumError{fn, str, errors.New("invalid bit size " + Itoa(bitSize))}
+}
+
+const intSize = 32 << (^uint(0) >> 63)
+
+// IntSize is the size in bits of an int or uint value.
+const IntSize = intSize
+
+const maxUint64 = 1<<64 - 1
+
+// ParseUint is like ParseInt but for unsigned numbers.
+//
+// A sign prefix is not permitted.
+func ParseUint(s string, base int, bitSize int) (uint64, error) {
+	const fnParseUint = "ParseUint"
+
+	if s == "" {
+		return 0, syntaxError(fnParseUint, s)
+	}
+
+	base0 := base == 0
+
+	s0 := s
+	switch {
+	case 2 <= base && base <= 36:
+		// valid base; nothing to do
+
+	case base == 0:
+		// Look for octal, hex prefix.
+		base = 10
+		if s[0] == '0' {
+			switch {
+			case len(s) >= 3 && lower(s[1]) == 'b':
+				base = 2
+				s = s[2:]
+			case len(s) >= 3 && lower(s[1]) == 'o':
+				base = 8
+				s = s[2:]
+			case len(s) >= 3 && lower(s[1]) == 'x':
+				base = 16
+				s = s[2:]
+			default:
+				base = 8
+				s = s[1:]
+			}
+		}
+
+	default:
+		return 0, baseError(fnParseUint, s0, base)
+	}
+
+	if bitSize == 0 {
+		bitSize = IntSize
+	} else if bitSize < 0 || bitSize > 64 {
+		return 0, bitSizeError(fnParseUint, s0, bitSize)
+	}
+
+	// Cutoff is the smallest number such that cutoff*base > maxUint64.
+	// Use compile-time constants for common cases.
+	var cutoff uint64
+	switch base {
+	case 10:
+		cutoff = maxUint64/10 + 1
+	case 16:
+		cutoff = maxUint64/16 + 1
+	default:
+		cutoff = maxUint64/uint64(base) + 1
+	}
+
+	maxVal := uint64(1)<<uint(bitSize) - 1
+
+	underscores := false
+	var n uint64
+	for _, c := range []byte(s) {
+		var d byte
+		switch {
+		case c == '_' && base0:
+			underscores = true
+			continue
+		case '0' <= c && c <= '9':
+			d = c - '0'
+		case 'a' <= lower(c) && lower(c) <= 'z':
+			d = lower(c) - 'a' + 10
+		default:
+			return 0, syntaxError(fnParseUint, s0)
+		}
+
+		if d >= byte(base) {
+			return 0, syntaxError(fnParseUint, s0)
+		}
+
+		if n >= cutoff {
+			// n*base overflows
+			return maxVal, rangeError(fnParseUint, s0)
+		}
+		n *= uint64(base)
+
+		n1 := n + uint64(d)
+		if n1 < n || n1 > maxVal {
+			// n+d overflows
+			return maxVal, rangeError(fnParseUint, s0)
+		}
+		n = n1
+	}
+
+	if underscores && !underscoreOK(s0) {
+		return 0, syntaxError(fnParseUint, s0)
+	}
+
+	return n, nil
+}
+
+// ParseInt interprets a string s in the given base (0, 2 to 36) and
+// bit size (0 to 64) and returns the corresponding value i.
+//
+// The string may begin with a leading sign: "+" or "-".
+//
+// If the base argument is 0, the true base is implied by the string's
+// prefix following the sign (if present): 2 for "0b", 8 for "0" or "0o",
+// 16 for "0x", and 10 otherwise. Also, for argument base 0 only,
+// underscore characters are permitted as defined by the Go syntax for
+// [integer literals].
+//
+// The bitSize argument specifies the integer type
+// that the result must fit into. Bit sizes 0, 8, 16, 32, and 64
+// correspond to int, int8, int16, int32, and int64.
+// If bitSize is below 0 or above 64, an error is returned.
+//
+// The errors that ParseInt returns have concrete type *NumError
+// and include err.Num = s. If s is empty or contains invalid
+// digits, err.Err = ErrSyntax and the returned value is 0;
+// if the value corresponding to s cannot be represented by a
+// signed integer of the given size, err.Err = ErrRange and the
+// returned value is the maximum magnitude integer of the
+// appropriate bitSize and sign.
+//
+// [integer literals]: https://go.dev/ref/spec#Integer_literals
+func ParseInt(s string, base int, bitSize int) (i int64, err error) {
+	const fnParseInt = "ParseInt"
+
+	if s == "" {
+		return 0, syntaxError(fnParseInt, s)
+	}
+
+	// Pick off leading sign.
+	s0 := s
+	neg := false
+	if s[0] == '+' {
+		s = s[1:]
+	} else if s[0] == '-' {
+		neg = true
+		s = s[1:]
+	}
+
+	// Convert unsigned and check range.
+	var un uint64
+	un, err = ParseUint(s, base, bitSize)
+	if err != nil && err.(*NumError).Err != ErrRange {
+		err.(*NumError).Func = fnParseInt
+		err.(*NumError).Num = s0
+		return 0, err
+	}
+
+	if bitSize == 0 {
+		bitSize = IntSize
+	}
+
+	cutoff := uint64(1 << uint(bitSize-1))
+	if !neg && un >= cutoff {
+		return int64(cutoff - 1), rangeError(fnParseInt, s0)
+	}
+	if neg && un > cutoff {
+		return -int64(cutoff), rangeError(fnParseInt, s0)
+	}
+	n := int64(un)
+	if neg {
+		n = -n
+	}
+	return n, nil
+}
+
+// Atoi is equivalent to ParseInt(s, 10, 0), converted to type int.
+func Atoi(s string) (int, error) {
+	const fnAtoi = "Atoi"
+
+	sLen := len(s)
+	if intSize == 32 && (0 < sLen && sLen < 10) ||
+		intSize == 64 && (0 < sLen && sLen < 19) {
+		// Fast path for small integers that fit int type.
+		s0 := s
+		if s[0] == '-' || s[0] == '+' {
+			s = s[1:]
+			if len(s) < 1 {
+				return 0, &NumError{fnAtoi, s0, ErrSyntax}
+			}
+		}
+
+		n := 0
+		for _, ch := range []byte(s) {
+			ch -= '0'
+			if ch > 9 {
+				return 0, &NumError{fnAtoi, s0, ErrSyntax}
+			}
+			n = n*10 + int(ch)
+		}
+		if s0[0] == '-' {
+			n = -n
+		}
+		return n, nil
+	}
+
+	// Slow path for invalid, big, or underscored integers.
+	i64, err := ParseInt(s, 10, 0)
+	if nerr, ok := err.(*NumError); ok {
+		nerr.Func = fnAtoi
+	}
+	return int(i64), err
+}
+
+// underscoreOK reports whether the underscores in s are allowed.
+// Checking them in this one function lets all the parsers skip over them simply.
+// Underscore must appear only between digits or between a base prefix and a digit.
+func underscoreOK(s string) bool {
+	// saw tracks the last character (class) we saw:
+	// ^ for beginning of number,
+	// 0 for a digit or base prefix,
+	// _ for an underscore,
+	// ! for none of the above.
+	saw := '^'
+	i := 0
+
+	// Optional sign.
+	if len(s) >= 1 && (s[0] == '-' || s[0] == '+') {
+		s = s[1:]
+	}
+
+	// Optional base prefix.
+	hex := false
+	if len(s) >= 2 && s[0] == '0' && (lower(s[1]) == 'b' || lower(s[1]) == 'o' || lower(s[1]) == 'x') {
+		i = 2
+		saw = '0' // base prefix counts as a digit for "underscore as digit separator"
+		hex = lower(s[1]) == 'x'
+	}
+
+	// Number proper.
+	for ; i < len(s); i++ {
+		// Digits are always okay.
+		if '0' <= s[i] && s[i] <= '9' || hex && 'a' <= lower(s[i]) && lower(s[i]) <= 'f' {
+			saw = '0'
+			continue
+		}
+		// Underscore must follow digit.
+		if s[i] == '_' {
+			if saw != '0' {
+				return false
+			}
+			saw = '_'
+			continue
+		}
+		// Underscore must also be followed by digit.
+		if saw == '_' {
+			return false
+		}
+		// Saw non-digit, non-underscore.
+		saw = '!'
+	}
+	return saw != '_'
+}
diff --git a/contrib/go/_std_1.18/src/strconv/bytealg.go b/contrib/go/_std_1.19/src/strconv/bytealg.go
index a2bb12c5f2..a2bb12c5f2 100644
--- a/contrib/go/_std_1.18/src/strconv/bytealg.go
+++ b/contrib/go/_std_1.19/src/strconv/bytealg.go
diff --git a/contrib/go/_std_1.18/src/strconv/ctoa.go b/contrib/go/_std_1.19/src/strconv/ctoa.go
index c16a2e579c..c16a2e579c 100644
--- a/contrib/go/_std_1.18/src/strconv/ctoa.go
+++ b/contrib/go/_std_1.19/src/strconv/ctoa.go
diff --git a/contrib/go/_std_1.18/src/strconv/decimal.go b/contrib/go/_std_1.19/src/strconv/decimal.go
index b58001888e..b58001888e 100644
--- a/contrib/go/_std_1.18/src/strconv/decimal.go
+++ b/contrib/go/_std_1.19/src/strconv/decimal.go
diff --git a/contrib/go/_std_1.19/src/strconv/doc.go b/contrib/go/_std_1.19/src/strconv/doc.go
new file mode 100644
index 0000000000..769ecd9a21
--- /dev/null
+++ b/contrib/go/_std_1.19/src/strconv/doc.go
@@ -0,0 +1,56 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package strconv implements conversions to and from string representations
+// of basic data types.
+//
+// # Numeric Conversions
+//
+// The most common numeric conversions are Atoi (string to int) and Itoa (int to string).
+//
+//	i, err := strconv.Atoi("-42")
+//	s := strconv.Itoa(-42)
+//
+// These assume decimal and the Go int type.
+//
+// ParseBool, ParseFloat, ParseInt, and ParseUint convert strings to values:
+//
+//	b, err := strconv.ParseBool("true")
+//	f, err := strconv.ParseFloat("3.1415", 64)
+//	i, err := strconv.ParseInt("-42", 10, 64)
+//	u, err := strconv.ParseUint("42", 10, 64)
+//
+// The parse functions return the widest type (float64, int64, and uint64),
+// but if the size argument specifies a narrower width the result can be
+// converted to that narrower type without data loss:
+//
+//	s := "2147483647" // biggest int32
+//	i64, err := strconv.ParseInt(s, 10, 32)
+//	...
+//	i := int32(i64)
+//
+// FormatBool, FormatFloat, FormatInt, and FormatUint convert values to strings:
+//
+//	s := strconv.FormatBool(true)
+//	s := strconv.FormatFloat(3.1415, 'E', -1, 64)
+//	s := strconv.FormatInt(-42, 16)
+//	s := strconv.FormatUint(42, 16)
+//
+// AppendBool, AppendFloat, AppendInt, and AppendUint are similar but
+// append the formatted value to a destination slice.
+//
+// # String Conversions
+//
+// Quote and QuoteToASCII convert strings to quoted Go string literals.
+// The latter guarantees that the result is an ASCII string, by escaping
+// any non-ASCII Unicode with \u:
+//
+//	q := strconv.Quote("Hello, 世界")
+//	q := strconv.QuoteToASCII("Hello, 世界")
+//
+// QuoteRune and QuoteRuneToASCII are similar but accept runes and
+// return quoted Go rune literals.
+//
+// Unquote and UnquoteChar unquote Go string and rune literals.
+package strconv
diff --git a/contrib/go/_std_1.19/src/strconv/eisel_lemire.go b/contrib/go/_std_1.19/src/strconv/eisel_lemire.go
new file mode 100644
index 0000000000..03842e5079
--- /dev/null
+++ b/contrib/go/_std_1.19/src/strconv/eisel_lemire.go
@@ -0,0 +1,884 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package strconv
+
+// This file implements the Eisel-Lemire ParseFloat algorithm, published in
+// 2020 and discussed extensively at
+// https://nigeltao.github.io/blog/2020/eisel-lemire.html
+//
+// The original C++ implementation is at
+// https://github.com/lemire/fast_double_parser/blob/644bef4306059d3be01a04e77d3cc84b379c596f/include/fast_double_parser.h#L840
+//
+// This Go re-implementation closely follows the C re-implementation at
+// https://github.com/google/wuffs/blob/ba3818cb6b473a2ed0b38ecfc07dbbd3a97e8ae7/internal/cgen/base/floatconv-submodule-code.c#L990
+//
+// Additional testing (on over several million test strings) is done by
+// https://github.com/nigeltao/parse-number-fxx-test-data/blob/5280dcfccf6d0b02a65ae282dad0b6d9de50e039/script/test-go-strconv.go
+
+import (
+	"math"
+	"math/bits"
+)
+
+func eiselLemire64(man uint64, exp10 int, neg bool) (f float64, ok bool) {
+	// The terse comments in this function body refer to sections of the
+	// https://nigeltao.github.io/blog/2020/eisel-lemire.html blog post.
+
+	// Exp10 Range.
+	if man == 0 {
+		if neg {
+			f = math.Float64frombits(0x8000000000000000) // Negative zero.
+		}
+		return f, true
+	}
+	if exp10 < detailedPowersOfTenMinExp10 || detailedPowersOfTenMaxExp10 < exp10 {
+		return 0, false
+	}
+
+	// Normalization.
+	clz := bits.LeadingZeros64(man)
+	man <<= uint(clz)
+	const float64ExponentBias = 1023
+	retExp2 := uint64(217706*exp10>>16+64+float64ExponentBias) - uint64(clz)
+
+	// Multiplication.
+	xHi, xLo := bits.Mul64(man, detailedPowersOfTen[exp10-detailedPowersOfTenMinExp10][1])
+
+	// Wider Approximation.
+	if xHi&0x1FF == 0x1FF && xLo+man < man {
+		yHi, yLo := bits.Mul64(man, detailedPowersOfTen[exp10-detailedPowersOfTenMinExp10][0])
+		mergedHi, mergedLo := xHi, xLo+yHi
+		if mergedLo < xLo {
+			mergedHi++
+		}
+		if mergedHi&0x1FF == 0x1FF && mergedLo+1 == 0 && yLo+man < man {
+			return 0, false
+		}
+		xHi, xLo = mergedHi, mergedLo
+	}
+
+	// Shifting to 54 Bits.
+	msb := xHi >> 63
+	retMantissa := xHi >> (msb + 9)
+	retExp2 -= 1 ^ msb
+
+	// Half-way Ambiguity.
+	if xLo == 0 && xHi&0x1FF == 0 && retMantissa&3 == 1 {
+		return 0, false
+	}
+
+	// From 54 to 53 Bits.
+	retMantissa += retMantissa & 1
+	retMantissa >>= 1
+	if retMantissa>>53 > 0 {
+		retMantissa >>= 1
+		retExp2 += 1
+	}
+	// retExp2 is a uint64. Zero or underflow means that we're in subnormal
+	// float64 space. 0x7FF or above means that we're in Inf/NaN float64 space.
+	//
+	// The if block is equivalent to (but has fewer branches than):
+	//   if retExp2 <= 0 || retExp2 >= 0x7FF { etc }
+	if retExp2-1 >= 0x7FF-1 {
+		return 0, false
+	}
+	retBits := retExp2<<52 | retMantissa&0x000FFFFFFFFFFFFF
+	if neg {
+		retBits |= 0x8000000000000000
+	}
+	return math.Float64frombits(retBits), true
+}
+
+func eiselLemire32(man uint64, exp10 int, neg bool) (f float32, ok bool) {
+	// The terse comments in this function body refer to sections of the
+	// https://nigeltao.github.io/blog/2020/eisel-lemire.html blog post.
+	//
+	// That blog post discusses the float64 flavor (11 exponent bits with a
+	// -1023 bias, 52 mantissa bits) of the algorithm, but the same approach
+	// applies to the float32 flavor (8 exponent bits with a -127 bias, 23
+	// mantissa bits). The computation here happens with 64-bit values (e.g.
+	// man, xHi, retMantissa) before finally converting to a 32-bit float.
+
+	// Exp10 Range.
+	if man == 0 {
+		if neg {
+			f = math.Float32frombits(0x80000000) // Negative zero.
+		}
+		return f, true
+	}
+	if exp10 < detailedPowersOfTenMinExp10 || detailedPowersOfTenMaxExp10 < exp10 {
+		return 0, false
+	}
+
+	// Normalization.
+	clz := bits.LeadingZeros64(man)
+	man <<= uint(clz)
+	const float32ExponentBias = 127
+	retExp2 := uint64(217706*exp10>>16+64+float32ExponentBias) - uint64(clz)
+
+	// Multiplication.
+	xHi, xLo := bits.Mul64(man, detailedPowersOfTen[exp10-detailedPowersOfTenMinExp10][1])
+
+	// Wider Approximation.
+	if xHi&0x3FFFFFFFFF == 0x3FFFFFFFFF && xLo+man < man {
+		yHi, yLo := bits.Mul64(man, detailedPowersOfTen[exp10-detailedPowersOfTenMinExp10][0])
+		mergedHi, mergedLo := xHi, xLo+yHi
+		if mergedLo < xLo {
+			mergedHi++
+		}
+		if mergedHi&0x3FFFFFFFFF == 0x3FFFFFFFFF && mergedLo+1 == 0 && yLo+man < man {
+			return 0, false
+		}
+		xHi, xLo = mergedHi, mergedLo
+	}
+
+	// Shifting to 54 Bits (and for float32, it's shifting to 25 bits).
+	msb := xHi >> 63
+	retMantissa := xHi >> (msb + 38)
+	retExp2 -= 1 ^ msb
+
+	// Half-way Ambiguity.
+	if xLo == 0 && xHi&0x3FFFFFFFFF == 0 && retMantissa&3 == 1 {
+		return 0, false
+	}
+
+	// From 54 to 53 Bits (and for float32, it's from 25 to 24 bits).
+	retMantissa += retMantissa & 1
+	retMantissa >>= 1
+	if retMantissa>>24 > 0 {
+		retMantissa >>= 1
+		retExp2 += 1
+	}
+	// retExp2 is a uint64. Zero or underflow means that we're in subnormal
+	// float32 space. 0xFF or above means that we're in Inf/NaN float32 space.
+	//
+	// The if block is equivalent to (but has fewer branches than):
+	//   if retExp2 <= 0 || retExp2 >= 0xFF { etc }
+	if retExp2-1 >= 0xFF-1 {
+		return 0, false
+	}
+	retBits := retExp2<<23 | retMantissa&0x007FFFFF
+	if neg {
+		retBits |= 0x80000000
+	}
+	return math.Float32frombits(uint32(retBits)), true
+}
+
+// detailedPowersOfTen{Min,Max}Exp10 is the power of 10 represented by the
+// first and last rows of detailedPowersOfTen. Both bounds are inclusive.
+const (
+	detailedPowersOfTenMinExp10 = -348
+	detailedPowersOfTenMaxExp10 = +347
+)
+
+// detailedPowersOfTen contains 128-bit mantissa approximations (rounded down)
+// to the powers of 10. For example:
+//
+//   - 1e43 ≈ (0xE596B7B0_C643C719                   * (2 ** 79))
+//   - 1e43 = (0xE596B7B0_C643C719_6D9CCD05_D0000000 * (2 ** 15))
+//
+// The mantissas are explicitly listed. The exponents are implied by a linear
+// expression with slope 217706.0/65536.0 ≈ log(10)/log(2).
+//
+// The table was generated by
+// https://github.com/google/wuffs/blob/ba3818cb6b473a2ed0b38ecfc07dbbd3a97e8ae7/script/print-mpb-powers-of-10.go
+var detailedPowersOfTen = [...][2]uint64{
+	{0x1732C869CD60E453, 0xFA8FD5A0081C0288}, // 1e-348
+	{0x0E7FBD42205C8EB4, 0x9C99E58405118195}, // 1e-347
+	{0x521FAC92A873B261, 0xC3C05EE50655E1FA}, // 1e-346
+	{0xE6A797B752909EF9, 0xF4B0769E47EB5A78}, // 1e-345
+	{0x9028BED2939A635C, 0x98EE4A22ECF3188B}, // 1e-344
+	{0x7432EE873880FC33, 0xBF29DCABA82FDEAE}, // 1e-343
+	{0x113FAA2906A13B3F, 0xEEF453D6923BD65A}, // 1e-342
+	{0x4AC7CA59A424C507, 0x9558B4661B6565F8}, // 1e-341
+	{0x5D79BCF00D2DF649, 0xBAAEE17FA23EBF76}, // 1e-340
+	{0xF4D82C2C107973DC, 0xE95A99DF8ACE6F53}, // 1e-339
+	{0x79071B9B8A4BE869, 0x91D8A02BB6C10594}, // 1e-338
+	{0x9748E2826CDEE284, 0xB64EC836A47146F9}, // 1e-337
+	{0xFD1B1B2308169B25, 0xE3E27A444D8D98B7}, // 1e-336
+	{0xFE30F0F5E50E20F7, 0x8E6D8C6AB0787F72}, // 1e-335
+	{0xBDBD2D335E51A935, 0xB208EF855C969F4F}, // 1e-334
+	{0xAD2C788035E61382, 0xDE8B2B66B3BC4723}, // 1e-333
+	{0x4C3BCB5021AFCC31, 0x8B16FB203055AC76}, // 1e-332
+	{0xDF4ABE242A1BBF3D, 0xADDCB9E83C6B1793}, // 1e-331
+	{0xD71D6DAD34A2AF0D, 0xD953E8624B85DD78}, // 1e-330
+	{0x8672648C40E5AD68, 0x87D4713D6F33AA6B}, // 1e-329
+	{0x680EFDAF511F18C2, 0xA9C98D8CCB009506}, // 1e-328
+	{0x0212BD1B2566DEF2, 0xD43BF0EFFDC0BA48}, // 1e-327
+	{0x014BB630F7604B57, 0x84A57695FE98746D}, // 1e-326
+	{0x419EA3BD35385E2D, 0xA5CED43B7E3E9188}, // 1e-325
+	{0x52064CAC828675B9, 0xCF42894A5DCE35EA}, // 1e-324
+	{0x7343EFEBD1940993, 0x818995CE7AA0E1B2}, // 1e-323
+	{0x1014EBE6C5F90BF8, 0xA1EBFB4219491A1F}, // 1e-322
+	{0xD41A26E077774EF6, 0xCA66FA129F9B60A6}, // 1e-321
+	{0x8920B098955522B4, 0xFD00B897478238D0}, // 1e-320
+	{0x55B46E5F5D5535B0, 0x9E20735E8CB16382}, // 1e-319
+	{0xEB2189F734AA831D, 0xC5A890362FDDBC62}, // 1e-318
+	{0xA5E9EC7501D523E4, 0xF712B443BBD52B7B}, // 1e-317
+	{0x47B233C92125366E, 0x9A6BB0AA55653B2D}, // 1e-316
+	{0x999EC0BB696E840A, 0xC1069CD4EABE89F8}, // 1e-315
+	{0xC00670EA43CA250D, 0xF148440A256E2C76}, // 1e-314
+	{0x380406926A5E5728, 0x96CD2A865764DBCA}, // 1e-313
+	{0xC605083704F5ECF2, 0xBC807527ED3E12BC}, // 1e-312
+	{0xF7864A44C633682E, 0xEBA09271E88D976B}, // 1e-311
+	{0x7AB3EE6AFBE0211D, 0x93445B8731587EA3}, // 1e-310
+	{0x5960EA05BAD82964, 0xB8157268FDAE9E4C}, // 1e-309
+	{0x6FB92487298E33BD, 0xE61ACF033D1A45DF}, // 1e-308
+	{0xA5D3B6D479F8E056, 0x8FD0C16206306BAB}, // 1e-307
+	{0x8F48A4899877186C, 0xB3C4F1BA87BC8696}, // 1e-306
+	{0x331ACDABFE94DE87, 0xE0B62E2929ABA83C}, // 1e-305
+	{0x9FF0C08B7F1D0B14, 0x8C71DCD9BA0B4925}, // 1e-304
+	{0x07ECF0AE5EE44DD9, 0xAF8E5410288E1B6F}, // 1e-303
+	{0xC9E82CD9F69D6150, 0xDB71E91432B1A24A}, // 1e-302
+	{0xBE311C083A225CD2, 0x892731AC9FAF056E}, // 1e-301
+	{0x6DBD630A48AAF406, 0xAB70FE17C79AC6CA}, // 1e-300
+	{0x092CBBCCDAD5B108, 0xD64D3D9DB981787D}, // 1e-299
+	{0x25BBF56008C58EA5, 0x85F0468293F0EB4E}, // 1e-298
+	{0xAF2AF2B80AF6F24E, 0xA76C582338ED2621}, // 1e-297
+	{0x1AF5AF660DB4AEE1, 0xD1476E2C07286FAA}, // 1e-296
+	{0x50D98D9FC890ED4D, 0x82CCA4DB847945CA}, // 1e-295
+	{0xE50FF107BAB528A0, 0xA37FCE126597973C}, // 1e-294
+	{0x1E53ED49A96272C8, 0xCC5FC196FEFD7D0C}, // 1e-293
+	{0x25E8E89C13BB0F7A, 0xFF77B1FCBEBCDC4F}, // 1e-292
+	{0x77B191618C54E9AC, 0x9FAACF3DF73609B1}, // 1e-291
+	{0xD59DF5B9EF6A2417, 0xC795830D75038C1D}, // 1e-290
+	{0x4B0573286B44AD1D, 0xF97AE3D0D2446F25}, // 1e-289
+	{0x4EE367F9430AEC32, 0x9BECCE62836AC577}, // 1e-288
+	{0x229C41F793CDA73F, 0xC2E801FB244576D5}, // 1e-287
+	{0x6B43527578C1110F, 0xF3A20279ED56D48A}, // 1e-286
+	{0x830A13896B78AAA9, 0x9845418C345644D6}, // 1e-285
+	{0x23CC986BC656D553, 0xBE5691EF416BD60C}, // 1e-284
+	{0x2CBFBE86B7EC8AA8, 0xEDEC366B11C6CB8F}, // 1e-283
+	{0x7BF7D71432F3D6A9, 0x94B3A202EB1C3F39}, // 1e-282
+	{0xDAF5CCD93FB0CC53, 0xB9E08A83A5E34F07}, // 1e-281
+	{0xD1B3400F8F9CFF68, 0xE858AD248F5C22C9}, // 1e-280
+	{0x23100809B9C21FA1, 0x91376C36D99995BE}, // 1e-279
+	{0xABD40A0C2832A78A, 0xB58547448FFFFB2D}, // 1e-278
+	{0x16C90C8F323F516C, 0xE2E69915B3FFF9F9}, // 1e-277
+	{0xAE3DA7D97F6792E3, 0x8DD01FAD907FFC3B}, // 1e-276
+	{0x99CD11CFDF41779C, 0xB1442798F49FFB4A}, // 1e-275
+	{0x40405643D711D583, 0xDD95317F31C7FA1D}, // 1e-274
+	{0x482835EA666B2572, 0x8A7D3EEF7F1CFC52}, // 1e-273
+	{0xDA3243650005EECF, 0xAD1C8EAB5EE43B66}, // 1e-272
+	{0x90BED43E40076A82, 0xD863B256369D4A40}, // 1e-271
+	{0x5A7744A6E804A291, 0x873E4F75E2224E68}, // 1e-270
+	{0x711515D0A205CB36, 0xA90DE3535AAAE202}, // 1e-269
+	{0x0D5A5B44CA873E03, 0xD3515C2831559A83}, // 1e-268
+	{0xE858790AFE9486C2, 0x8412D9991ED58091}, // 1e-267
+	{0x626E974DBE39A872, 0xA5178FFF668AE0B6}, // 1e-266
+	{0xFB0A3D212DC8128F, 0xCE5D73FF402D98E3}, // 1e-265
+	{0x7CE66634BC9D0B99, 0x80FA687F881C7F8E}, // 1e-264
+	{0x1C1FFFC1EBC44E80, 0xA139029F6A239F72}, // 1e-263
+	{0xA327FFB266B56220, 0xC987434744AC874E}, // 1e-262
+	{0x4BF1FF9F0062BAA8, 0xFBE9141915D7A922}, // 1e-261
+	{0x6F773FC3603DB4A9, 0x9D71AC8FADA6C9B5}, // 1e-260
+	{0xCB550FB4384D21D3, 0xC4CE17B399107C22}, // 1e-259
+	{0x7E2A53A146606A48, 0xF6019DA07F549B2B}, // 1e-258
+	{0x2EDA7444CBFC426D, 0x99C102844F94E0FB}, // 1e-257
+	{0xFA911155FEFB5308, 0xC0314325637A1939}, // 1e-256
+	{0x793555AB7EBA27CA, 0xF03D93EEBC589F88}, // 1e-255
+	{0x4BC1558B2F3458DE, 0x96267C7535B763B5}, // 1e-254
+	{0x9EB1AAEDFB016F16, 0xBBB01B9283253CA2}, // 1e-253
+	{0x465E15A979C1CADC, 0xEA9C227723EE8BCB}, // 1e-252
+	{0x0BFACD89EC191EC9, 0x92A1958A7675175F}, // 1e-251
+	{0xCEF980EC671F667B, 0xB749FAED14125D36}, // 1e-250
+	{0x82B7E12780E7401A, 0xE51C79A85916F484}, // 1e-249
+	{0xD1B2ECB8B0908810, 0x8F31CC0937AE58D2}, // 1e-248
+	{0x861FA7E6DCB4AA15, 0xB2FE3F0B8599EF07}, // 1e-247
+	{0x67A791E093E1D49A, 0xDFBDCECE67006AC9}, // 1e-246
+	{0xE0C8BB2C5C6D24E0, 0x8BD6A141006042BD}, // 1e-245
+	{0x58FAE9F773886E18, 0xAECC49914078536D}, // 1e-244
+	{0xAF39A475506A899E, 0xDA7F5BF590966848}, // 1e-243
+	{0x6D8406C952429603, 0x888F99797A5E012D}, // 1e-242
+	{0xC8E5087BA6D33B83, 0xAAB37FD7D8F58178}, // 1e-241
+	{0xFB1E4A9A90880A64, 0xD5605FCDCF32E1D6}, // 1e-240
+	{0x5CF2EEA09A55067F, 0x855C3BE0A17FCD26}, // 1e-239
+	{0xF42FAA48C0EA481E, 0xA6B34AD8C9DFC06F}, // 1e-238
+	{0xF13B94DAF124DA26, 0xD0601D8EFC57B08B}, // 1e-237
+	{0x76C53D08D6B70858, 0x823C12795DB6CE57}, // 1e-236
+	{0x54768C4B0C64CA6E, 0xA2CB1717B52481ED}, // 1e-235
+	{0xA9942F5DCF7DFD09, 0xCB7DDCDDA26DA268}, // 1e-234
+	{0xD3F93B35435D7C4C, 0xFE5D54150B090B02}, // 1e-233
+	{0xC47BC5014A1A6DAF, 0x9EFA548D26E5A6E1}, // 1e-232
+	{0x359AB6419CA1091B, 0xC6B8E9B0709F109A}, // 1e-231
+	{0xC30163D203C94B62, 0xF867241C8CC6D4C0}, // 1e-230
+	{0x79E0DE63425DCF1D, 0x9B407691D7FC44F8}, // 1e-229
+	{0x985915FC12F542E4, 0xC21094364DFB5636}, // 1e-228
+	{0x3E6F5B7B17B2939D, 0xF294B943E17A2BC4}, // 1e-227
+	{0xA705992CEECF9C42, 0x979CF3CA6CEC5B5A}, // 1e-226
+	{0x50C6FF782A838353, 0xBD8430BD08277231}, // 1e-225
+	{0xA4F8BF5635246428, 0xECE53CEC4A314EBD}, // 1e-224
+	{0x871B7795E136BE99, 0x940F4613AE5ED136}, // 1e-223
+	{0x28E2557B59846E3F, 0xB913179899F68584}, // 1e-222
+	{0x331AEADA2FE589CF, 0xE757DD7EC07426E5}, // 1e-221
+	{0x3FF0D2C85DEF7621, 0x9096EA6F3848984F}, // 1e-220
+	{0x0FED077A756B53A9, 0xB4BCA50B065ABE63}, // 1e-219
+	{0xD3E8495912C62894, 0xE1EBCE4DC7F16DFB}, // 1e-218
+	{0x64712DD7ABBBD95C, 0x8D3360F09CF6E4BD}, // 1e-217
+	{0xBD8D794D96AACFB3, 0xB080392CC4349DEC}, // 1e-216
+	{0xECF0D7A0FC5583A0, 0xDCA04777F541C567}, // 1e-215
+	{0xF41686C49DB57244, 0x89E42CAAF9491B60}, // 1e-214
+	{0x311C2875C522CED5, 0xAC5D37D5B79B6239}, // 1e-213
+	{0x7D633293366B828B, 0xD77485CB25823AC7}, // 1e-212
+	{0xAE5DFF9C02033197, 0x86A8D39EF77164BC}, // 1e-211
+	{0xD9F57F830283FDFC, 0xA8530886B54DBDEB}, // 1e-210
+	{0xD072DF63C324FD7B, 0xD267CAA862A12D66}, // 1e-209
+	{0x4247CB9E59F71E6D, 0x8380DEA93DA4BC60}, // 1e-208
+	{0x52D9BE85F074E608, 0xA46116538D0DEB78}, // 1e-207
+	{0x67902E276C921F8B, 0xCD795BE870516656}, // 1e-206
+	{0x00BA1CD8A3DB53B6, 0x806BD9714632DFF6}, // 1e-205
+	{0x80E8A40ECCD228A4, 0xA086CFCD97BF97F3}, // 1e-204
+	{0x6122CD128006B2CD, 0xC8A883C0FDAF7DF0}, // 1e-203
+	{0x796B805720085F81, 0xFAD2A4B13D1B5D6C}, // 1e-202
+	{0xCBE3303674053BB0, 0x9CC3A6EEC6311A63}, // 1e-201
+	{0xBEDBFC4411068A9C, 0xC3F490AA77BD60FC}, // 1e-200
+	{0xEE92FB5515482D44, 0xF4F1B4D515ACB93B}, // 1e-199
+	{0x751BDD152D4D1C4A, 0x991711052D8BF3C5}, // 1e-198
+	{0xD262D45A78A0635D, 0xBF5CD54678EEF0B6}, // 1e-197
+	{0x86FB897116C87C34, 0xEF340A98172AACE4}, // 1e-196
+	{0xD45D35E6AE3D4DA0, 0x9580869F0E7AAC0E}, // 1e-195
+	{0x8974836059CCA109, 0xBAE0A846D2195712}, // 1e-194
+	{0x2BD1A438703FC94B, 0xE998D258869FACD7}, // 1e-193
+	{0x7B6306A34627DDCF, 0x91FF83775423CC06}, // 1e-192
+	{0x1A3BC84C17B1D542, 0xB67F6455292CBF08}, // 1e-191
+	{0x20CABA5F1D9E4A93, 0xE41F3D6A7377EECA}, // 1e-190
+	{0x547EB47B7282EE9C, 0x8E938662882AF53E}, // 1e-189
+	{0xE99E619A4F23AA43, 0xB23867FB2A35B28D}, // 1e-188
+	{0x6405FA00E2EC94D4, 0xDEC681F9F4C31F31}, // 1e-187
+	{0xDE83BC408DD3DD04, 0x8B3C113C38F9F37E}, // 1e-186
+	{0x9624AB50B148D445, 0xAE0B158B4738705E}, // 1e-185
+	{0x3BADD624DD9B0957, 0xD98DDAEE19068C76}, // 1e-184
+	{0xE54CA5D70A80E5D6, 0x87F8A8D4CFA417C9}, // 1e-183
+	{0x5E9FCF4CCD211F4C, 0xA9F6D30A038D1DBC}, // 1e-182
+	{0x7647C3200069671F, 0xD47487CC8470652B}, // 1e-181
+	{0x29ECD9F40041E073, 0x84C8D4DFD2C63F3B}, // 1e-180
+	{0xF468107100525890, 0xA5FB0A17C777CF09}, // 1e-179
+	{0x7182148D4066EEB4, 0xCF79CC9DB955C2CC}, // 1e-178
+	{0xC6F14CD848405530, 0x81AC1FE293D599BF}, // 1e-177
+	{0xB8ADA00E5A506A7C, 0xA21727DB38CB002F}, // 1e-176
+	{0xA6D90811F0E4851C, 0xCA9CF1D206FDC03B}, // 1e-175
+	{0x908F4A166D1DA663, 0xFD442E4688BD304A}, // 1e-174
+	{0x9A598E4E043287FE, 0x9E4A9CEC15763E2E}, // 1e-173
+	{0x40EFF1E1853F29FD, 0xC5DD44271AD3CDBA}, // 1e-172
+	{0xD12BEE59E68EF47C, 0xF7549530E188C128}, // 1e-171
+	{0x82BB74F8301958CE, 0x9A94DD3E8CF578B9}, // 1e-170
+	{0xE36A52363C1FAF01, 0xC13A148E3032D6E7}, // 1e-169
+	{0xDC44E6C3CB279AC1, 0xF18899B1BC3F8CA1}, // 1e-168
+	{0x29AB103A5EF8C0B9, 0x96F5600F15A7B7E5}, // 1e-167
+	{0x7415D448F6B6F0E7, 0xBCB2B812DB11A5DE}, // 1e-166
+	{0x111B495B3464AD21, 0xEBDF661791D60F56}, // 1e-165
+	{0xCAB10DD900BEEC34, 0x936B9FCEBB25C995}, // 1e-164
+	{0x3D5D514F40EEA742, 0xB84687C269EF3BFB}, // 1e-163
+	{0x0CB4A5A3112A5112, 0xE65829B3046B0AFA}, // 1e-162
+	{0x47F0E785EABA72AB, 0x8FF71A0FE2C2E6DC}, // 1e-161
+	{0x59ED216765690F56, 0xB3F4E093DB73A093}, // 1e-160
+	{0x306869C13EC3532C, 0xE0F218B8D25088B8}, // 1e-159
+	{0x1E414218C73A13FB, 0x8C974F7383725573}, // 1e-158
+	{0xE5D1929EF90898FA, 0xAFBD2350644EEACF}, // 1e-157
+	{0xDF45F746B74ABF39, 0xDBAC6C247D62A583}, // 1e-156
+	{0x6B8BBA8C328EB783, 0x894BC396CE5DA772}, // 1e-155
+	{0x066EA92F3F326564, 0xAB9EB47C81F5114F}, // 1e-154
+	{0xC80A537B0EFEFEBD, 0xD686619BA27255A2}, // 1e-153
+	{0xBD06742CE95F5F36, 0x8613FD0145877585}, // 1e-152
+	{0x2C48113823B73704, 0xA798FC4196E952E7}, // 1e-151
+	{0xF75A15862CA504C5, 0xD17F3B51FCA3A7A0}, // 1e-150
+	{0x9A984D73DBE722FB, 0x82EF85133DE648C4}, // 1e-149
+	{0xC13E60D0D2E0EBBA, 0xA3AB66580D5FDAF5}, // 1e-148
+	{0x318DF905079926A8, 0xCC963FEE10B7D1B3}, // 1e-147
+	{0xFDF17746497F7052, 0xFFBBCFE994E5C61F}, // 1e-146
+	{0xFEB6EA8BEDEFA633, 0x9FD561F1FD0F9BD3}, // 1e-145
+	{0xFE64A52EE96B8FC0, 0xC7CABA6E7C5382C8}, // 1e-144
+	{0x3DFDCE7AA3C673B0, 0xF9BD690A1B68637B}, // 1e-143
+	{0x06BEA10CA65C084E, 0x9C1661A651213E2D}, // 1e-142
+	{0x486E494FCFF30A62, 0xC31BFA0FE5698DB8}, // 1e-141
+	{0x5A89DBA3C3EFCCFA, 0xF3E2F893DEC3F126}, // 1e-140
+	{0xF89629465A75E01C, 0x986DDB5C6B3A76B7}, // 1e-139
+	{0xF6BBB397F1135823, 0xBE89523386091465}, // 1e-138
+	{0x746AA07DED582E2C, 0xEE2BA6C0678B597F}, // 1e-137
+	{0xA8C2A44EB4571CDC, 0x94DB483840B717EF}, // 1e-136
+	{0x92F34D62616CE413, 0xBA121A4650E4DDEB}, // 1e-135
+	{0x77B020BAF9C81D17, 0xE896A0D7E51E1566}, // 1e-134
+	{0x0ACE1474DC1D122E, 0x915E2486EF32CD60}, // 1e-133
+	{0x0D819992132456BA, 0xB5B5ADA8AAFF80B8}, // 1e-132
+	{0x10E1FFF697ED6C69, 0xE3231912D5BF60E6}, // 1e-131
+	{0xCA8D3FFA1EF463C1, 0x8DF5EFABC5979C8F}, // 1e-130
+	{0xBD308FF8A6B17CB2, 0xB1736B96B6FD83B3}, // 1e-129
+	{0xAC7CB3F6D05DDBDE, 0xDDD0467C64BCE4A0}, // 1e-128
+	{0x6BCDF07A423AA96B, 0x8AA22C0DBEF60EE4}, // 1e-127
+	{0x86C16C98D2C953C6, 0xAD4AB7112EB3929D}, // 1e-126
+	{0xE871C7BF077BA8B7, 0xD89D64D57A607744}, // 1e-125
+	{0x11471CD764AD4972, 0x87625F056C7C4A8B}, // 1e-124
+	{0xD598E40D3DD89BCF, 0xA93AF6C6C79B5D2D}, // 1e-123
+	{0x4AFF1D108D4EC2C3, 0xD389B47879823479}, // 1e-122
+	{0xCEDF722A585139BA, 0x843610CB4BF160CB}, // 1e-121
+	{0xC2974EB4EE658828, 0xA54394FE1EEDB8FE}, // 1e-120
+	{0x733D226229FEEA32, 0xCE947A3DA6A9273E}, // 1e-119
+	{0x0806357D5A3F525F, 0x811CCC668829B887}, // 1e-118
+	{0xCA07C2DCB0CF26F7, 0xA163FF802A3426A8}, // 1e-117
+	{0xFC89B393DD02F0B5, 0xC9BCFF6034C13052}, // 1e-116
+	{0xBBAC2078D443ACE2, 0xFC2C3F3841F17C67}, // 1e-115
+	{0xD54B944B84AA4C0D, 0x9D9BA7832936EDC0}, // 1e-114
+	{0x0A9E795E65D4DF11, 0xC5029163F384A931}, // 1e-113
+	{0x4D4617B5FF4A16D5, 0xF64335BCF065D37D}, // 1e-112
+	{0x504BCED1BF8E4E45, 0x99EA0196163FA42E}, // 1e-111
+	{0xE45EC2862F71E1D6, 0xC06481FB9BCF8D39}, // 1e-110
+	{0x5D767327BB4E5A4C, 0xF07DA27A82C37088}, // 1e-109
+	{0x3A6A07F8D510F86F, 0x964E858C91BA2655}, // 1e-108
+	{0x890489F70A55368B, 0xBBE226EFB628AFEA}, // 1e-107
+	{0x2B45AC74CCEA842E, 0xEADAB0ABA3B2DBE5}, // 1e-106
+	{0x3B0B8BC90012929D, 0x92C8AE6B464FC96F}, // 1e-105
+	{0x09CE6EBB40173744, 0xB77ADA0617E3BBCB}, // 1e-104
+	{0xCC420A6A101D0515, 0xE55990879DDCAABD}, // 1e-103
+	{0x9FA946824A12232D, 0x8F57FA54C2A9EAB6}, // 1e-102
+	{0x47939822DC96ABF9, 0xB32DF8E9F3546564}, // 1e-101
+	{0x59787E2B93BC56F7, 0xDFF9772470297EBD}, // 1e-100
+	{0x57EB4EDB3C55B65A, 0x8BFBEA76C619EF36}, // 1e-99
+	{0xEDE622920B6B23F1, 0xAEFAE51477A06B03}, // 1e-98
+	{0xE95FAB368E45ECED, 0xDAB99E59958885C4}, // 1e-97
+	{0x11DBCB0218EBB414, 0x88B402F7FD75539B}, // 1e-96
+	{0xD652BDC29F26A119, 0xAAE103B5FCD2A881}, // 1e-95
+	{0x4BE76D3346F0495F, 0xD59944A37C0752A2}, // 1e-94
+	{0x6F70A4400C562DDB, 0x857FCAE62D8493A5}, // 1e-93
+	{0xCB4CCD500F6BB952, 0xA6DFBD9FB8E5B88E}, // 1e-92
+	{0x7E2000A41346A7A7, 0xD097AD07A71F26B2}, // 1e-91
+	{0x8ED400668C0C28C8, 0x825ECC24C873782F}, // 1e-90
+	{0x728900802F0F32FA, 0xA2F67F2DFA90563B}, // 1e-89
+	{0x4F2B40A03AD2FFB9, 0xCBB41EF979346BCA}, // 1e-88
+	{0xE2F610C84987BFA8, 0xFEA126B7D78186BC}, // 1e-87
+	{0x0DD9CA7D2DF4D7C9, 0x9F24B832E6B0F436}, // 1e-86
+	{0x91503D1C79720DBB, 0xC6EDE63FA05D3143}, // 1e-85
+	{0x75A44C6397CE912A, 0xF8A95FCF88747D94}, // 1e-84
+	{0xC986AFBE3EE11ABA, 0x9B69DBE1B548CE7C}, // 1e-83
+	{0xFBE85BADCE996168, 0xC24452DA229B021B}, // 1e-82
+	{0xFAE27299423FB9C3, 0xF2D56790AB41C2A2}, // 1e-81
+	{0xDCCD879FC967D41A, 0x97C560BA6B0919A5}, // 1e-80
+	{0x5400E987BBC1C920, 0xBDB6B8E905CB600F}, // 1e-79
+	{0x290123E9AAB23B68, 0xED246723473E3813}, // 1e-78
+	{0xF9A0B6720AAF6521, 0x9436C0760C86E30B}, // 1e-77
+	{0xF808E40E8D5B3E69, 0xB94470938FA89BCE}, // 1e-76
+	{0xB60B1D1230B20E04, 0xE7958CB87392C2C2}, // 1e-75
+	{0xB1C6F22B5E6F48C2, 0x90BD77F3483BB9B9}, // 1e-74
+	{0x1E38AEB6360B1AF3, 0xB4ECD5F01A4AA828}, // 1e-73
+	{0x25C6DA63C38DE1B0, 0xE2280B6C20DD5232}, // 1e-72
+	{0x579C487E5A38AD0E, 0x8D590723948A535F}, // 1e-71
+	{0x2D835A9DF0C6D851, 0xB0AF48EC79ACE837}, // 1e-70
+	{0xF8E431456CF88E65, 0xDCDB1B2798182244}, // 1e-69
+	{0x1B8E9ECB641B58FF, 0x8A08F0F8BF0F156B}, // 1e-68
+	{0xE272467E3D222F3F, 0xAC8B2D36EED2DAC5}, // 1e-67
+	{0x5B0ED81DCC6ABB0F, 0xD7ADF884AA879177}, // 1e-66
+	{0x98E947129FC2B4E9, 0x86CCBB52EA94BAEA}, // 1e-65
+	{0x3F2398D747B36224, 0xA87FEA27A539E9A5}, // 1e-64
+	{0x8EEC7F0D19A03AAD, 0xD29FE4B18E88640E}, // 1e-63
+	{0x1953CF68300424AC, 0x83A3EEEEF9153E89}, // 1e-62
+	{0x5FA8C3423C052DD7, 0xA48CEAAAB75A8E2B}, // 1e-61
+	{0x3792F412CB06794D, 0xCDB02555653131B6}, // 1e-60
+	{0xE2BBD88BBEE40BD0, 0x808E17555F3EBF11}, // 1e-59
+	{0x5B6ACEAEAE9D0EC4, 0xA0B19D2AB70E6ED6}, // 1e-58
+	{0xF245825A5A445275, 0xC8DE047564D20A8B}, // 1e-57
+	{0xEED6E2F0F0D56712, 0xFB158592BE068D2E}, // 1e-56
+	{0x55464DD69685606B, 0x9CED737BB6C4183D}, // 1e-55
+	{0xAA97E14C3C26B886, 0xC428D05AA4751E4C}, // 1e-54
+	{0xD53DD99F4B3066A8, 0xF53304714D9265DF}, // 1e-53
+	{0xE546A8038EFE4029, 0x993FE2C6D07B7FAB}, // 1e-52
+	{0xDE98520472BDD033, 0xBF8FDB78849A5F96}, // 1e-51
+	{0x963E66858F6D4440, 0xEF73D256A5C0F77C}, // 1e-50
+	{0xDDE7001379A44AA8, 0x95A8637627989AAD}, // 1e-49
+	{0x5560C018580D5D52, 0xBB127C53B17EC159}, // 1e-48
+	{0xAAB8F01E6E10B4A6, 0xE9D71B689DDE71AF}, // 1e-47
+	{0xCAB3961304CA70E8, 0x9226712162AB070D}, // 1e-46
+	{0x3D607B97C5FD0D22, 0xB6B00D69BB55C8D1}, // 1e-45
+	{0x8CB89A7DB77C506A, 0xE45C10C42A2B3B05}, // 1e-44
+	{0x77F3608E92ADB242, 0x8EB98A7A9A5B04E3}, // 1e-43
+	{0x55F038B237591ED3, 0xB267ED1940F1C61C}, // 1e-42
+	{0x6B6C46DEC52F6688, 0xDF01E85F912E37A3}, // 1e-41
+	{0x2323AC4B3B3DA015, 0x8B61313BBABCE2C6}, // 1e-40
+	{0xABEC975E0A0D081A, 0xAE397D8AA96C1B77}, // 1e-39
+	{0x96E7BD358C904A21, 0xD9C7DCED53C72255}, // 1e-38
+	{0x7E50D64177DA2E54, 0x881CEA14545C7575}, // 1e-37
+	{0xDDE50BD1D5D0B9E9, 0xAA242499697392D2}, // 1e-36
+	{0x955E4EC64B44E864, 0xD4AD2DBFC3D07787}, // 1e-35
+	{0xBD5AF13BEF0B113E, 0x84EC3C97DA624AB4}, // 1e-34
+	{0xECB1AD8AEACDD58E, 0xA6274BBDD0FADD61}, // 1e-33
+	{0x67DE18EDA5814AF2, 0xCFB11EAD453994BA}, // 1e-32
+	{0x80EACF948770CED7, 0x81CEB32C4B43FCF4}, // 1e-31
+	{0xA1258379A94D028D, 0xA2425FF75E14FC31}, // 1e-30
+	{0x096EE45813A04330, 0xCAD2F7F5359A3B3E}, // 1e-29
+	{0x8BCA9D6E188853FC, 0xFD87B5F28300CA0D}, // 1e-28
+	{0x775EA264CF55347D, 0x9E74D1B791E07E48}, // 1e-27
+	{0x95364AFE032A819D, 0xC612062576589DDA}, // 1e-26
+	{0x3A83DDBD83F52204, 0xF79687AED3EEC551}, // 1e-25
+	{0xC4926A9672793542, 0x9ABE14CD44753B52}, // 1e-24
+	{0x75B7053C0F178293, 0xC16D9A0095928A27}, // 1e-23
+	{0x5324C68B12DD6338, 0xF1C90080BAF72CB1}, // 1e-22
+	{0xD3F6FC16EBCA5E03, 0x971DA05074DA7BEE}, // 1e-21
+	{0x88F4BB1CA6BCF584, 0xBCE5086492111AEA}, // 1e-20
+	{0x2B31E9E3D06C32E5, 0xEC1E4A7DB69561A5}, // 1e-19
+	{0x3AFF322E62439FCF, 0x9392EE8E921D5D07}, // 1e-18
+	{0x09BEFEB9FAD487C2, 0xB877AA3236A4B449}, // 1e-17
+	{0x4C2EBE687989A9B3, 0xE69594BEC44DE15B}, // 1e-16
+	{0x0F9D37014BF60A10, 0x901D7CF73AB0ACD9}, // 1e-15
+	{0x538484C19EF38C94, 0xB424DC35095CD80F}, // 1e-14
+	{0x2865A5F206B06FB9, 0xE12E13424BB40E13}, // 1e-13
+	{0xF93F87B7442E45D3, 0x8CBCCC096F5088CB}, // 1e-12
+	{0xF78F69A51539D748, 0xAFEBFF0BCB24AAFE}, // 1e-11
+	{0xB573440E5A884D1B, 0xDBE6FECEBDEDD5BE}, // 1e-10
+	{0x31680A88F8953030, 0x89705F4136B4A597}, // 1e-9
+	{0xFDC20D2B36BA7C3D, 0xABCC77118461CEFC}, // 1e-8
+	{0x3D32907604691B4C, 0xD6BF94D5E57A42BC}, // 1e-7
+	{0xA63F9A49C2C1B10F, 0x8637BD05AF6C69B5}, // 1e-6
+	{0x0FCF80DC33721D53, 0xA7C5AC471B478423}, // 1e-5
+	{0xD3C36113404EA4A8, 0xD1B71758E219652B}, // 1e-4
+	{0x645A1CAC083126E9, 0x83126E978D4FDF3B}, // 1e-3
+	{0x3D70A3D70A3D70A3, 0xA3D70A3D70A3D70A}, // 1e-2
+	{0xCCCCCCCCCCCCCCCC, 0xCCCCCCCCCCCCCCCC}, // 1e-1
+	{0x0000000000000000, 0x8000000000000000}, // 1e0
+	{0x0000000000000000, 0xA000000000000000}, // 1e1
+	{0x0000000000000000, 0xC800000000000000}, // 1e2
+	{0x0000000000000000, 0xFA00000000000000}, // 1e3
+	{0x0000000000000000, 0x9C40000000000000}, // 1e4
+	{0x0000000000000000, 0xC350000000000000}, // 1e5
+	{0x0000000000000000, 0xF424000000000000}, // 1e6
+	{0x0000000000000000, 0x9896800000000000}, // 1e7
+	{0x0000000000000000, 0xBEBC200000000000}, // 1e8
+	{0x0000000000000000, 0xEE6B280000000000}, // 1e9
+	{0x0000000000000000, 0x9502F90000000000}, // 1e10
+	{0x0000000000000000, 0xBA43B74000000000}, // 1e11
+	{0x0000000000000000, 0xE8D4A51000000000}, // 1e12
+	{0x0000000000000000, 0x9184E72A00000000}, // 1e13
+	{0x0000000000000000, 0xB5E620F480000000}, // 1e14
+	{0x0000000000000000, 0xE35FA931A0000000}, // 1e15
+	{0x0000000000000000, 0x8E1BC9BF04000000}, // 1e16
+	{0x0000000000000000, 0xB1A2BC2EC5000000}, // 1e17
+	{0x0000000000000000, 0xDE0B6B3A76400000}, // 1e18
+	{0x0000000000000000, 0x8AC7230489E80000}, // 1e19
+	{0x0000000000000000, 0xAD78EBC5AC620000}, // 1e20
+	{0x0000000000000000, 0xD8D726B7177A8000}, // 1e21
+	{0x0000000000000000, 0x878678326EAC9000}, // 1e22
+	{0x0000000000000000, 0xA968163F0A57B400}, // 1e23
+	{0x0000000000000000, 0xD3C21BCECCEDA100}, // 1e24
+	{0x0000000000000000, 0x84595161401484A0}, // 1e25
+	{0x0000000000000000, 0xA56FA5B99019A5C8}, // 1e26
+	{0x0000000000000000, 0xCECB8F27F4200F3A}, // 1e27
+	{0x4000000000000000, 0x813F3978F8940984}, // 1e28
+	{0x5000000000000000, 0xA18F07D736B90BE5}, // 1e29
+	{0xA400000000000000, 0xC9F2C9CD04674EDE}, // 1e30
+	{0x4D00000000000000, 0xFC6F7C4045812296}, // 1e31
+	{0xF020000000000000, 0x9DC5ADA82B70B59D}, // 1e32
+	{0x6C28000000000000, 0xC5371912364CE305}, // 1e33
+	{0xC732000000000000, 0xF684DF56C3E01BC6}, // 1e34
+	{0x3C7F400000000000, 0x9A130B963A6C115C}, // 1e35
+	{0x4B9F100000000000, 0xC097CE7BC90715B3}, // 1e36
+	{0x1E86D40000000000, 0xF0BDC21ABB48DB20}, // 1e37
+	{0x1314448000000000, 0x96769950B50D88F4}, // 1e38
+	{0x17D955A000000000, 0xBC143FA4E250EB31}, // 1e39
+	{0x5DCFAB0800000000, 0xEB194F8E1AE525FD}, // 1e40
+	{0x5AA1CAE500000000, 0x92EFD1B8D0CF37BE}, // 1e41
+	{0xF14A3D9E40000000, 0xB7ABC627050305AD}, // 1e42
+	{0x6D9CCD05D0000000, 0xE596B7B0C643C719}, // 1e43
+	{0xE4820023A2000000, 0x8F7E32CE7BEA5C6F}, // 1e44
+	{0xDDA2802C8A800000, 0xB35DBF821AE4F38B}, // 1e45
+	{0xD50B2037AD200000, 0xE0352F62A19E306E}, // 1e46
+	{0x4526F422CC340000, 0x8C213D9DA502DE45}, // 1e47
+	{0x9670B12B7F410000, 0xAF298D050E4395D6}, // 1e48
+	{0x3C0CDD765F114000, 0xDAF3F04651D47B4C}, // 1e49
+	{0xA5880A69FB6AC800, 0x88D8762BF324CD0F}, // 1e50
+	{0x8EEA0D047A457A00, 0xAB0E93B6EFEE0053}, // 1e51
+	{0x72A4904598D6D880, 0xD5D238A4ABE98068}, // 1e52
+	{0x47A6DA2B7F864750, 0x85A36366EB71F041}, // 1e53
+	{0x999090B65F67D924, 0xA70C3C40A64E6C51}, // 1e54
+	{0xFFF4B4E3F741CF6D, 0xD0CF4B50CFE20765}, // 1e55
+	{0xBFF8F10E7A8921A4, 0x82818F1281ED449F}, // 1e56
+	{0xAFF72D52192B6A0D, 0xA321F2D7226895C7}, // 1e57
+	{0x9BF4F8A69F764490, 0xCBEA6F8CEB02BB39}, // 1e58
+	{0x02F236D04753D5B4, 0xFEE50B7025C36A08}, // 1e59
+	{0x01D762422C946590, 0x9F4F2726179A2245}, // 1e60
+	{0x424D3AD2B7B97EF5, 0xC722F0EF9D80AAD6}, // 1e61
+	{0xD2E0898765A7DEB2, 0xF8EBAD2B84E0D58B}, // 1e62
+	{0x63CC55F49F88EB2F, 0x9B934C3B330C8577}, // 1e63
+	{0x3CBF6B71C76B25FB, 0xC2781F49FFCFA6D5}, // 1e64
+	{0x8BEF464E3945EF7A, 0xF316271C7FC3908A}, // 1e65
+	{0x97758BF0E3CBB5AC, 0x97EDD871CFDA3A56}, // 1e66
+	{0x3D52EEED1CBEA317, 0xBDE94E8E43D0C8EC}, // 1e67
+	{0x4CA7AAA863EE4BDD, 0xED63A231D4C4FB27}, // 1e68
+	{0x8FE8CAA93E74EF6A, 0x945E455F24FB1CF8}, // 1e69
+	{0xB3E2FD538E122B44, 0xB975D6B6EE39E436}, // 1e70
+	{0x60DBBCA87196B616, 0xE7D34C64A9C85D44}, // 1e71
+	{0xBC8955E946FE31CD, 0x90E40FBEEA1D3A4A}, // 1e72
+	{0x6BABAB6398BDBE41, 0xB51D13AEA4A488DD}, // 1e73
+	{0xC696963C7EED2DD1, 0xE264589A4DCDAB14}, // 1e74
+	{0xFC1E1DE5CF543CA2, 0x8D7EB76070A08AEC}, // 1e75
+	{0x3B25A55F43294BCB, 0xB0DE65388CC8ADA8}, // 1e76
+	{0x49EF0EB713F39EBE, 0xDD15FE86AFFAD912}, // 1e77
+	{0x6E3569326C784337, 0x8A2DBF142DFCC7AB}, // 1e78
+	{0x49C2C37F07965404, 0xACB92ED9397BF996}, // 1e79
+	{0xDC33745EC97BE906, 0xD7E77A8F87DAF7FB}, // 1e80
+	{0x69A028BB3DED71A3, 0x86F0AC99B4E8DAFD}, // 1e81
+	{0xC40832EA0D68CE0C, 0xA8ACD7C0222311BC}, // 1e82
+	{0xF50A3FA490C30190, 0xD2D80DB02AABD62B}, // 1e83
+	{0x792667C6DA79E0FA, 0x83C7088E1AAB65DB}, // 1e84
+	{0x577001B891185938, 0xA4B8CAB1A1563F52}, // 1e85
+	{0xED4C0226B55E6F86, 0xCDE6FD5E09ABCF26}, // 1e86
+	{0x544F8158315B05B4, 0x80B05E5AC60B6178}, // 1e87
+	{0x696361AE3DB1C721, 0xA0DC75F1778E39D6}, // 1e88
+	{0x03BC3A19CD1E38E9, 0xC913936DD571C84C}, // 1e89
+	{0x04AB48A04065C723, 0xFB5878494ACE3A5F}, // 1e90
+	{0x62EB0D64283F9C76, 0x9D174B2DCEC0E47B}, // 1e91
+	{0x3BA5D0BD324F8394, 0xC45D1DF942711D9A}, // 1e92
+	{0xCA8F44EC7EE36479, 0xF5746577930D6500}, // 1e93
+	{0x7E998B13CF4E1ECB, 0x9968BF6ABBE85F20}, // 1e94
+	{0x9E3FEDD8C321A67E, 0xBFC2EF456AE276E8}, // 1e95
+	{0xC5CFE94EF3EA101E, 0xEFB3AB16C59B14A2}, // 1e96
+	{0xBBA1F1D158724A12, 0x95D04AEE3B80ECE5}, // 1e97
+	{0x2A8A6E45AE8EDC97, 0xBB445DA9CA61281F}, // 1e98
+	{0xF52D09D71A3293BD, 0xEA1575143CF97226}, // 1e99
+	{0x593C2626705F9C56, 0x924D692CA61BE758}, // 1e100
+	{0x6F8B2FB00C77836C, 0xB6E0C377CFA2E12E}, // 1e101
+	{0x0B6DFB9C0F956447, 0xE498F455C38B997A}, // 1e102
+	{0x4724BD4189BD5EAC, 0x8EDF98B59A373FEC}, // 1e103
+	{0x58EDEC91EC2CB657, 0xB2977EE300C50FE7}, // 1e104
+	{0x2F2967B66737E3ED, 0xDF3D5E9BC0F653E1}, // 1e105
+	{0xBD79E0D20082EE74, 0x8B865B215899F46C}, // 1e106
+	{0xECD8590680A3AA11, 0xAE67F1E9AEC07187}, // 1e107
+	{0xE80E6F4820CC9495, 0xDA01EE641A708DE9}, // 1e108
+	{0x3109058D147FDCDD, 0x884134FE908658B2}, // 1e109
+	{0xBD4B46F0599FD415, 0xAA51823E34A7EEDE}, // 1e110
+	{0x6C9E18AC7007C91A, 0xD4E5E2CDC1D1EA96}, // 1e111
+	{0x03E2CF6BC604DDB0, 0x850FADC09923329E}, // 1e112
+	{0x84DB8346B786151C, 0xA6539930BF6BFF45}, // 1e113
+	{0xE612641865679A63, 0xCFE87F7CEF46FF16}, // 1e114
+	{0x4FCB7E8F3F60C07E, 0x81F14FAE158C5F6E}, // 1e115
+	{0xE3BE5E330F38F09D, 0xA26DA3999AEF7749}, // 1e116
+	{0x5CADF5BFD3072CC5, 0xCB090C8001AB551C}, // 1e117
+	{0x73D9732FC7C8F7F6, 0xFDCB4FA002162A63}, // 1e118
+	{0x2867E7FDDCDD9AFA, 0x9E9F11C4014DDA7E}, // 1e119
+	{0xB281E1FD541501B8, 0xC646D63501A1511D}, // 1e120
+	{0x1F225A7CA91A4226, 0xF7D88BC24209A565}, // 1e121
+	{0x3375788DE9B06958, 0x9AE757596946075F}, // 1e122
+	{0x0052D6B1641C83AE, 0xC1A12D2FC3978937}, // 1e123
+	{0xC0678C5DBD23A49A, 0xF209787BB47D6B84}, // 1e124
+	{0xF840B7BA963646E0, 0x9745EB4D50CE6332}, // 1e125
+	{0xB650E5A93BC3D898, 0xBD176620A501FBFF}, // 1e126
+	{0xA3E51F138AB4CEBE, 0xEC5D3FA8CE427AFF}, // 1e127
+	{0xC66F336C36B10137, 0x93BA47C980E98CDF}, // 1e128
+	{0xB80B0047445D4184, 0xB8A8D9BBE123F017}, // 1e129
+	{0xA60DC059157491E5, 0xE6D3102AD96CEC1D}, // 1e130
+	{0x87C89837AD68DB2F, 0x9043EA1AC7E41392}, // 1e131
+	{0x29BABE4598C311FB, 0xB454E4A179DD1877}, // 1e132
+	{0xF4296DD6FEF3D67A, 0xE16A1DC9D8545E94}, // 1e133
+	{0x1899E4A65F58660C, 0x8CE2529E2734BB1D}, // 1e134
+	{0x5EC05DCFF72E7F8F, 0xB01AE745B101E9E4}, // 1e135
+	{0x76707543F4FA1F73, 0xDC21A1171D42645D}, // 1e136
+	{0x6A06494A791C53A8, 0x899504AE72497EBA}, // 1e137
+	{0x0487DB9D17636892, 0xABFA45DA0EDBDE69}, // 1e138
+	{0x45A9D2845D3C42B6, 0xD6F8D7509292D603}, // 1e139
+	{0x0B8A2392BA45A9B2, 0x865B86925B9BC5C2}, // 1e140
+	{0x8E6CAC7768D7141E, 0xA7F26836F282B732}, // 1e141
+	{0x3207D795430CD926, 0xD1EF0244AF2364FF}, // 1e142
+	{0x7F44E6BD49E807B8, 0x8335616AED761F1F}, // 1e143
+	{0x5F16206C9C6209A6, 0xA402B9C5A8D3A6E7}, // 1e144
+	{0x36DBA887C37A8C0F, 0xCD036837130890A1}, // 1e145
+	{0xC2494954DA2C9789, 0x802221226BE55A64}, // 1e146
+	{0xF2DB9BAA10B7BD6C, 0xA02AA96B06DEB0FD}, // 1e147
+	{0x6F92829494E5ACC7, 0xC83553C5C8965D3D}, // 1e148
+	{0xCB772339BA1F17F9, 0xFA42A8B73ABBF48C}, // 1e149
+	{0xFF2A760414536EFB, 0x9C69A97284B578D7}, // 1e150
+	{0xFEF5138519684ABA, 0xC38413CF25E2D70D}, // 1e151
+	{0x7EB258665FC25D69, 0xF46518C2EF5B8CD1}, // 1e152
+	{0xEF2F773FFBD97A61, 0x98BF2F79D5993802}, // 1e153
+	{0xAAFB550FFACFD8FA, 0xBEEEFB584AFF8603}, // 1e154
+	{0x95BA2A53F983CF38, 0xEEAABA2E5DBF6784}, // 1e155
+	{0xDD945A747BF26183, 0x952AB45CFA97A0B2}, // 1e156
+	{0x94F971119AEEF9E4, 0xBA756174393D88DF}, // 1e157
+	{0x7A37CD5601AAB85D, 0xE912B9D1478CEB17}, // 1e158
+	{0xAC62E055C10AB33A, 0x91ABB422CCB812EE}, // 1e159
+	{0x577B986B314D6009, 0xB616A12B7FE617AA}, // 1e160
+	{0xED5A7E85FDA0B80B, 0xE39C49765FDF9D94}, // 1e161
+	{0x14588F13BE847307, 0x8E41ADE9FBEBC27D}, // 1e162
+	{0x596EB2D8AE258FC8, 0xB1D219647AE6B31C}, // 1e163
+	{0x6FCA5F8ED9AEF3BB, 0xDE469FBD99A05FE3}, // 1e164
+	{0x25DE7BB9480D5854, 0x8AEC23D680043BEE}, // 1e165
+	{0xAF561AA79A10AE6A, 0xADA72CCC20054AE9}, // 1e166
+	{0x1B2BA1518094DA04, 0xD910F7FF28069DA4}, // 1e167
+	{0x90FB44D2F05D0842, 0x87AA9AFF79042286}, // 1e168
+	{0x353A1607AC744A53, 0xA99541BF57452B28}, // 1e169
+	{0x42889B8997915CE8, 0xD3FA922F2D1675F2}, // 1e170
+	{0x69956135FEBADA11, 0x847C9B5D7C2E09B7}, // 1e171
+	{0x43FAB9837E699095, 0xA59BC234DB398C25}, // 1e172
+	{0x94F967E45E03F4BB, 0xCF02B2C21207EF2E}, // 1e173
+	{0x1D1BE0EEBAC278F5, 0x8161AFB94B44F57D}, // 1e174
+	{0x6462D92A69731732, 0xA1BA1BA79E1632DC}, // 1e175
+	{0x7D7B8F7503CFDCFE, 0xCA28A291859BBF93}, // 1e176
+	{0x5CDA735244C3D43E, 0xFCB2CB35E702AF78}, // 1e177
+	{0x3A0888136AFA64A7, 0x9DEFBF01B061ADAB}, // 1e178
+	{0x088AAA1845B8FDD0, 0xC56BAEC21C7A1916}, // 1e179
+	{0x8AAD549E57273D45, 0xF6C69A72A3989F5B}, // 1e180
+	{0x36AC54E2F678864B, 0x9A3C2087A63F6399}, // 1e181
+	{0x84576A1BB416A7DD, 0xC0CB28A98FCF3C7F}, // 1e182
+	{0x656D44A2A11C51D5, 0xF0FDF2D3F3C30B9F}, // 1e183
+	{0x9F644AE5A4B1B325, 0x969EB7C47859E743}, // 1e184
+	{0x873D5D9F0DDE1FEE, 0xBC4665B596706114}, // 1e185
+	{0xA90CB506D155A7EA, 0xEB57FF22FC0C7959}, // 1e186
+	{0x09A7F12442D588F2, 0x9316FF75DD87CBD8}, // 1e187
+	{0x0C11ED6D538AEB2F, 0xB7DCBF5354E9BECE}, // 1e188
+	{0x8F1668C8A86DA5FA, 0xE5D3EF282A242E81}, // 1e189
+	{0xF96E017D694487BC, 0x8FA475791A569D10}, // 1e190
+	{0x37C981DCC395A9AC, 0xB38D92D760EC4455}, // 1e191
+	{0x85BBE253F47B1417, 0xE070F78D3927556A}, // 1e192
+	{0x93956D7478CCEC8E, 0x8C469AB843B89562}, // 1e193
+	{0x387AC8D1970027B2, 0xAF58416654A6BABB}, // 1e194
+	{0x06997B05FCC0319E, 0xDB2E51BFE9D0696A}, // 1e195
+	{0x441FECE3BDF81F03, 0x88FCF317F22241E2}, // 1e196
+	{0xD527E81CAD7626C3, 0xAB3C2FDDEEAAD25A}, // 1e197
+	{0x8A71E223D8D3B074, 0xD60B3BD56A5586F1}, // 1e198
+	{0xF6872D5667844E49, 0x85C7056562757456}, // 1e199
+	{0xB428F8AC016561DB, 0xA738C6BEBB12D16C}, // 1e200
+	{0xE13336D701BEBA52, 0xD106F86E69D785C7}, // 1e201
+	{0xECC0024661173473, 0x82A45B450226B39C}, // 1e202
+	{0x27F002D7F95D0190, 0xA34D721642B06084}, // 1e203
+	{0x31EC038DF7B441F4, 0xCC20CE9BD35C78A5}, // 1e204
+	{0x7E67047175A15271, 0xFF290242C83396CE}, // 1e205
+	{0x0F0062C6E984D386, 0x9F79A169BD203E41}, // 1e206
+	{0x52C07B78A3E60868, 0xC75809C42C684DD1}, // 1e207
+	{0xA7709A56CCDF8A82, 0xF92E0C3537826145}, // 1e208
+	{0x88A66076400BB691, 0x9BBCC7A142B17CCB}, // 1e209
+	{0x6ACFF893D00EA435, 0xC2ABF989935DDBFE}, // 1e210
+	{0x0583F6B8C4124D43, 0xF356F7EBF83552FE}, // 1e211
+	{0xC3727A337A8B704A, 0x98165AF37B2153DE}, // 1e212
+	{0x744F18C0592E4C5C, 0xBE1BF1B059E9A8D6}, // 1e213
+	{0x1162DEF06F79DF73, 0xEDA2EE1C7064130C}, // 1e214
+	{0x8ADDCB5645AC2BA8, 0x9485D4D1C63E8BE7}, // 1e215
+	{0x6D953E2BD7173692, 0xB9A74A0637CE2EE1}, // 1e216
+	{0xC8FA8DB6CCDD0437, 0xE8111C87C5C1BA99}, // 1e217
+	{0x1D9C9892400A22A2, 0x910AB1D4DB9914A0}, // 1e218
+	{0x2503BEB6D00CAB4B, 0xB54D5E4A127F59C8}, // 1e219
+	{0x2E44AE64840FD61D, 0xE2A0B5DC971F303A}, // 1e220
+	{0x5CEAECFED289E5D2, 0x8DA471A9DE737E24}, // 1e221
+	{0x7425A83E872C5F47, 0xB10D8E1456105DAD}, // 1e222
+	{0xD12F124E28F77719, 0xDD50F1996B947518}, // 1e223
+	{0x82BD6B70D99AAA6F, 0x8A5296FFE33CC92F}, // 1e224
+	{0x636CC64D1001550B, 0xACE73CBFDC0BFB7B}, // 1e225
+	{0x3C47F7E05401AA4E, 0xD8210BEFD30EFA5A}, // 1e226
+	{0x65ACFAEC34810A71, 0x8714A775E3E95C78}, // 1e227
+	{0x7F1839A741A14D0D, 0xA8D9D1535CE3B396}, // 1e228
+	{0x1EDE48111209A050, 0xD31045A8341CA07C}, // 1e229
+	{0x934AED0AAB460432, 0x83EA2B892091E44D}, // 1e230
+	{0xF81DA84D5617853F, 0xA4E4B66B68B65D60}, // 1e231
+	{0x36251260AB9D668E, 0xCE1DE40642E3F4B9}, // 1e232
+	{0xC1D72B7C6B426019, 0x80D2AE83E9CE78F3}, // 1e233
+	{0xB24CF65B8612F81F, 0xA1075A24E4421730}, // 1e234
+	{0xDEE033F26797B627, 0xC94930AE1D529CFC}, // 1e235
+	{0x169840EF017DA3B1, 0xFB9B7CD9A4A7443C}, // 1e236
+	{0x8E1F289560EE864E, 0x9D412E0806E88AA5}, // 1e237
+	{0xF1A6F2BAB92A27E2, 0xC491798A08A2AD4E}, // 1e238
+	{0xAE10AF696774B1DB, 0xF5B5D7EC8ACB58A2}, // 1e239
+	{0xACCA6DA1E0A8EF29, 0x9991A6F3D6BF1765}, // 1e240
+	{0x17FD090A58D32AF3, 0xBFF610B0CC6EDD3F}, // 1e241
+	{0xDDFC4B4CEF07F5B0, 0xEFF394DCFF8A948E}, // 1e242
+	{0x4ABDAF101564F98E, 0x95F83D0A1FB69CD9}, // 1e243
+	{0x9D6D1AD41ABE37F1, 0xBB764C4CA7A4440F}, // 1e244
+	{0x84C86189216DC5ED, 0xEA53DF5FD18D5513}, // 1e245
+	{0x32FD3CF5B4E49BB4, 0x92746B9BE2F8552C}, // 1e246
+	{0x3FBC8C33221DC2A1, 0xB7118682DBB66A77}, // 1e247
+	{0x0FABAF3FEAA5334A, 0xE4D5E82392A40515}, // 1e248
+	{0x29CB4D87F2A7400E, 0x8F05B1163BA6832D}, // 1e249
+	{0x743E20E9EF511012, 0xB2C71D5BCA9023F8}, // 1e250
+	{0x914DA9246B255416, 0xDF78E4B2BD342CF6}, // 1e251
+	{0x1AD089B6C2F7548E, 0x8BAB8EEFB6409C1A}, // 1e252
+	{0xA184AC2473B529B1, 0xAE9672ABA3D0C320}, // 1e253
+	{0xC9E5D72D90A2741E, 0xDA3C0F568CC4F3E8}, // 1e254
+	{0x7E2FA67C7A658892, 0x8865899617FB1871}, // 1e255
+	{0xDDBB901B98FEEAB7, 0xAA7EEBFB9DF9DE8D}, // 1e256
+	{0x552A74227F3EA565, 0xD51EA6FA85785631}, // 1e257
+	{0xD53A88958F87275F, 0x8533285C936B35DE}, // 1e258
+	{0x8A892ABAF368F137, 0xA67FF273B8460356}, // 1e259
+	{0x2D2B7569B0432D85, 0xD01FEF10A657842C}, // 1e260
+	{0x9C3B29620E29FC73, 0x8213F56A67F6B29B}, // 1e261
+	{0x8349F3BA91B47B8F, 0xA298F2C501F45F42}, // 1e262
+	{0x241C70A936219A73, 0xCB3F2F7642717713}, // 1e263
+	{0xED238CD383AA0110, 0xFE0EFB53D30DD4D7}, // 1e264
+	{0xF4363804324A40AA, 0x9EC95D1463E8A506}, // 1e265
+	{0xB143C6053EDCD0D5, 0xC67BB4597CE2CE48}, // 1e266
+	{0xDD94B7868E94050A, 0xF81AA16FDC1B81DA}, // 1e267
+	{0xCA7CF2B4191C8326, 0x9B10A4E5E9913128}, // 1e268
+	{0xFD1C2F611F63A3F0, 0xC1D4CE1F63F57D72}, // 1e269
+	{0xBC633B39673C8CEC, 0xF24A01A73CF2DCCF}, // 1e270
+	{0xD5BE0503E085D813, 0x976E41088617CA01}, // 1e271
+	{0x4B2D8644D8A74E18, 0xBD49D14AA79DBC82}, // 1e272
+	{0xDDF8E7D60ED1219E, 0xEC9C459D51852BA2}, // 1e273
+	{0xCABB90E5C942B503, 0x93E1AB8252F33B45}, // 1e274
+	{0x3D6A751F3B936243, 0xB8DA1662E7B00A17}, // 1e275
+	{0x0CC512670A783AD4, 0xE7109BFBA19C0C9D}, // 1e276
+	{0x27FB2B80668B24C5, 0x906A617D450187E2}, // 1e277
+	{0xB1F9F660802DEDF6, 0xB484F9DC9641E9DA}, // 1e278
+	{0x5E7873F8A0396973, 0xE1A63853BBD26451}, // 1e279
+	{0xDB0B487B6423E1E8, 0x8D07E33455637EB2}, // 1e280
+	{0x91CE1A9A3D2CDA62, 0xB049DC016ABC5E5F}, // 1e281
+	{0x7641A140CC7810FB, 0xDC5C5301C56B75F7}, // 1e282
+	{0xA9E904C87FCB0A9D, 0x89B9B3E11B6329BA}, // 1e283
+	{0x546345FA9FBDCD44, 0xAC2820D9623BF429}, // 1e284
+	{0xA97C177947AD4095, 0xD732290FBACAF133}, // 1e285
+	{0x49ED8EABCCCC485D, 0x867F59A9D4BED6C0}, // 1e286
+	{0x5C68F256BFFF5A74, 0xA81F301449EE8C70}, // 1e287
+	{0x73832EEC6FFF3111, 0xD226FC195C6A2F8C}, // 1e288
+	{0xC831FD53C5FF7EAB, 0x83585D8FD9C25DB7}, // 1e289
+	{0xBA3E7CA8B77F5E55, 0xA42E74F3D032F525}, // 1e290
+	{0x28CE1BD2E55F35EB, 0xCD3A1230C43FB26F}, // 1e291
+	{0x7980D163CF5B81B3, 0x80444B5E7AA7CF85}, // 1e292
+	{0xD7E105BCC332621F, 0xA0555E361951C366}, // 1e293
+	{0x8DD9472BF3FEFAA7, 0xC86AB5C39FA63440}, // 1e294
+	{0xB14F98F6F0FEB951, 0xFA856334878FC150}, // 1e295
+	{0x6ED1BF9A569F33D3, 0x9C935E00D4B9D8D2}, // 1e296
+	{0x0A862F80EC4700C8, 0xC3B8358109E84F07}, // 1e297
+	{0xCD27BB612758C0FA, 0xF4A642E14C6262C8}, // 1e298
+	{0x8038D51CB897789C, 0x98E7E9CCCFBD7DBD}, // 1e299
+	{0xE0470A63E6BD56C3, 0xBF21E44003ACDD2C}, // 1e300
+	{0x1858CCFCE06CAC74, 0xEEEA5D5004981478}, // 1e301
+	{0x0F37801E0C43EBC8, 0x95527A5202DF0CCB}, // 1e302
+	{0xD30560258F54E6BA, 0xBAA718E68396CFFD}, // 1e303
+	{0x47C6B82EF32A2069, 0xE950DF20247C83FD}, // 1e304
+	{0x4CDC331D57FA5441, 0x91D28B7416CDD27E}, // 1e305
+	{0xE0133FE4ADF8E952, 0xB6472E511C81471D}, // 1e306
+	{0x58180FDDD97723A6, 0xE3D8F9E563A198E5}, // 1e307
+	{0x570F09EAA7EA7648, 0x8E679C2F5E44FF8F}, // 1e308
+	{0x2CD2CC6551E513DA, 0xB201833B35D63F73}, // 1e309
+	{0xF8077F7EA65E58D1, 0xDE81E40A034BCF4F}, // 1e310
+	{0xFB04AFAF27FAF782, 0x8B112E86420F6191}, // 1e311
+	{0x79C5DB9AF1F9B563, 0xADD57A27D29339F6}, // 1e312
+	{0x18375281AE7822BC, 0xD94AD8B1C7380874}, // 1e313
+	{0x8F2293910D0B15B5, 0x87CEC76F1C830548}, // 1e314
+	{0xB2EB3875504DDB22, 0xA9C2794AE3A3C69A}, // 1e315
+	{0x5FA60692A46151EB, 0xD433179D9C8CB841}, // 1e316
+	{0xDBC7C41BA6BCD333, 0x849FEEC281D7F328}, // 1e317
+	{0x12B9B522906C0800, 0xA5C7EA73224DEFF3}, // 1e318
+	{0xD768226B34870A00, 0xCF39E50FEAE16BEF}, // 1e319
+	{0xE6A1158300D46640, 0x81842F29F2CCE375}, // 1e320
+	{0x60495AE3C1097FD0, 0xA1E53AF46F801C53}, // 1e321
+	{0x385BB19CB14BDFC4, 0xCA5E89B18B602368}, // 1e322
+	{0x46729E03DD9ED7B5, 0xFCF62C1DEE382C42}, // 1e323
+	{0x6C07A2C26A8346D1, 0x9E19DB92B4E31BA9}, // 1e324
+	{0xC7098B7305241885, 0xC5A05277621BE293}, // 1e325
+	{0xB8CBEE4FC66D1EA7, 0xF70867153AA2DB38}, // 1e326
+	{0x737F74F1DC043328, 0x9A65406D44A5C903}, // 1e327
+	{0x505F522E53053FF2, 0xC0FE908895CF3B44}, // 1e328
+	{0x647726B9E7C68FEF, 0xF13E34AABB430A15}, // 1e329
+	{0x5ECA783430DC19F5, 0x96C6E0EAB509E64D}, // 1e330
+	{0xB67D16413D132072, 0xBC789925624C5FE0}, // 1e331
+	{0xE41C5BD18C57E88F, 0xEB96BF6EBADF77D8}, // 1e332
+	{0x8E91B962F7B6F159, 0x933E37A534CBAAE7}, // 1e333
+	{0x723627BBB5A4ADB0, 0xB80DC58E81FE95A1}, // 1e334
+	{0xCEC3B1AAA30DD91C, 0xE61136F2227E3B09}, // 1e335
+	{0x213A4F0AA5E8A7B1, 0x8FCAC257558EE4E6}, // 1e336
+	{0xA988E2CD4F62D19D, 0xB3BD72ED2AF29E1F}, // 1e337
+	{0x93EB1B80A33B8605, 0xE0ACCFA875AF45A7}, // 1e338
+	{0xBC72F130660533C3, 0x8C6C01C9498D8B88}, // 1e339
+	{0xEB8FAD7C7F8680B4, 0xAF87023B9BF0EE6A}, // 1e340
+	{0xA67398DB9F6820E1, 0xDB68C2CA82ED2A05}, // 1e341
+	{0x88083F8943A1148C, 0x892179BE91D43A43}, // 1e342
+	{0x6A0A4F6B948959B0, 0xAB69D82E364948D4}, // 1e343
+	{0x848CE34679ABB01C, 0xD6444E39C3DB9B09}, // 1e344
+	{0xF2D80E0C0C0B4E11, 0x85EAB0E41A6940E5}, // 1e345
+	{0x6F8E118F0F0E2195, 0xA7655D1D2103911F}, // 1e346
+	{0x4B7195F2D2D1A9FB, 0xD13EB46469447567}, // 1e347
+}
diff --git a/contrib/go/_std_1.19/src/strconv/ftoa.go b/contrib/go/_std_1.19/src/strconv/ftoa.go
new file mode 100644
index 0000000000..f602d0ffe6
--- /dev/null
+++ b/contrib/go/_std_1.19/src/strconv/ftoa.go
@@ -0,0 +1,585 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Binary to decimal floating point conversion.
+// Algorithm:
+//   1) store mantissa in multiprecision decimal
+//   2) shift decimal by exponent
+//   3) read digits out & format
+
+package strconv
+
+import "math"
+
+// TODO: move elsewhere?
+type floatInfo struct {
+	mantbits uint
+	expbits  uint
+	bias     int
+}
+
+var float32info = floatInfo{23, 8, -127}
+var float64info = floatInfo{52, 11, -1023}
+
+// FormatFloat converts the floating-point number f to a string,
+// according to the format fmt and precision prec. It rounds the
+// result assuming that the original was obtained from a floating-point
+// value of bitSize bits (32 for float32, 64 for float64).
+//
+// The format fmt is one of
+// 'b' (-ddddp±ddd, a binary exponent),
+// 'e' (-d.dddde±dd, a decimal exponent),
+// 'E' (-d.ddddE±dd, a decimal exponent),
+// 'f' (-ddd.dddd, no exponent),
+// 'g' ('e' for large exponents, 'f' otherwise),
+// 'G' ('E' for large exponents, 'f' otherwise),
+// 'x' (-0xd.ddddp±ddd, a hexadecimal fraction and binary exponent), or
+// 'X' (-0Xd.ddddP±ddd, a hexadecimal fraction and binary exponent).
+//
+// The precision prec controls the number of digits (excluding the exponent)
+// printed by the 'e', 'E', 'f', 'g', 'G', 'x', and 'X' formats.
+// For 'e', 'E', 'f', 'x', and 'X', it is the number of digits after the decimal point.
+// For 'g' and 'G' it is the maximum number of significant digits (trailing
+// zeros are removed).
+// The special precision -1 uses the smallest number of digits
+// necessary such that ParseFloat will return f exactly.
+func FormatFloat(f float64, fmt byte, prec, bitSize int) string {
+	return string(genericFtoa(make([]byte, 0, max(prec+4, 24)), f, fmt, prec, bitSize))
+}
+
+// AppendFloat appends the string form of the floating-point number f,
+// as generated by FormatFloat, to dst and returns the extended buffer.
+func AppendFloat(dst []byte, f float64, fmt byte, prec, bitSize int) []byte {
+	return genericFtoa(dst, f, fmt, prec, bitSize)
+}
+
+func genericFtoa(dst []byte, val float64, fmt byte, prec, bitSize int) []byte {
+	var bits uint64
+	var flt *floatInfo
+	switch bitSize {
+	case 32:
+		bits = uint64(math.Float32bits(float32(val)))
+		flt = &float32info
+	case 64:
+		bits = math.Float64bits(val)
+		flt = &float64info
+	default:
+		panic("strconv: illegal AppendFloat/FormatFloat bitSize")
+	}
+
+	neg := bits>>(flt.expbits+flt.mantbits) != 0
+	exp := int(bits>>flt.mantbits) & (1<<flt.expbits - 1)
+	mant := bits & (uint64(1)<<flt.mantbits - 1)
+
+	switch exp {
+	case 1<<flt.expbits - 1:
+		// Inf, NaN
+		var s string
+		switch {
+		case mant != 0:
+			s = "NaN"
+		case neg:
+			s = "-Inf"
+		default:
+			s = "+Inf"
+		}
+		return append(dst, s...)
+
+	case 0:
+		// denormalized
+		exp++
+
+	default:
+		// add implicit top bit
+		mant |= uint64(1) << flt.mantbits
+	}
+	exp += flt.bias
+
+	// Pick off easy binary, hex formats.
+	if fmt == 'b' {
+		return fmtB(dst, neg, mant, exp, flt)
+	}
+	if fmt == 'x' || fmt == 'X' {
+		return fmtX(dst, prec, fmt, neg, mant, exp, flt)
+	}
+
+	if !optimize {
+		return bigFtoa(dst, prec, fmt, neg, mant, exp, flt)
+	}
+
+	var digs decimalSlice
+	ok := false
+	// Negative precision means "only as much as needed to be exact."
+	shortest := prec < 0
+	if shortest {
+		// Use Ryu algorithm.
+		var buf [32]byte
+		digs.d = buf[:]
+		ryuFtoaShortest(&digs, mant, exp-int(flt.mantbits), flt)
+		ok = true
+		// Precision for shortest representation mode.
+		switch fmt {
+		case 'e', 'E':
+			prec = max(digs.nd-1, 0)
+		case 'f':
+			prec = max(digs.nd-digs.dp, 0)
+		case 'g', 'G':
+			prec = digs.nd
+		}
+	} else if fmt != 'f' {
+		// Fixed number of digits.
+		digits := prec
+		switch fmt {
+		case 'e', 'E':
+			digits++
+		case 'g', 'G':
+			if prec == 0 {
+				prec = 1
+			}
+			digits = prec
+		default:
+			// Invalid mode.
+			digits = 1
+		}
+		var buf [24]byte
+		if bitSize == 32 && digits <= 9 {
+			digs.d = buf[:]
+			ryuFtoaFixed32(&digs, uint32(mant), exp-int(flt.mantbits), digits)
+			ok = true
+		} else if digits <= 18 {
+			digs.d = buf[:]
+			ryuFtoaFixed64(&digs, mant, exp-int(flt.mantbits), digits)
+			ok = true
+		}
+	}
+	if !ok {
+		return bigFtoa(dst, prec, fmt, neg, mant, exp, flt)
+	}
+	return formatDigits(dst, shortest, neg, digs, prec, fmt)
+}
+
+// bigFtoa uses multiprecision computations to format a float.
+func bigFtoa(dst []byte, prec int, fmt byte, neg bool, mant uint64, exp int, flt *floatInfo) []byte {
+	d := new(decimal)
+	d.Assign(mant)
+	d.Shift(exp - int(flt.mantbits))
+	var digs decimalSlice
+	shortest := prec < 0
+	if shortest {
+		roundShortest(d, mant, exp, flt)
+		digs = decimalSlice{d: d.d[:], nd: d.nd, dp: d.dp}
+		// Precision for shortest representation mode.
+		switch fmt {
+		case 'e', 'E':
+			prec = digs.nd - 1
+		case 'f':
+			prec = max(digs.nd-digs.dp, 0)
+		case 'g', 'G':
+			prec = digs.nd
+		}
+	} else {
+		// Round appropriately.
+		switch fmt {
+		case 'e', 'E':
+			d.Round(prec + 1)
+		case 'f':
+			d.Round(d.dp + prec)
+		case 'g', 'G':
+			if prec == 0 {
+				prec = 1
+			}
+			d.Round(prec)
+		}
+		digs = decimalSlice{d: d.d[:], nd: d.nd, dp: d.dp}
+	}
+	return formatDigits(dst, shortest, neg, digs, prec, fmt)
+}
+
+func formatDigits(dst []byte, shortest bool, neg bool, digs decimalSlice, prec int, fmt byte) []byte {
+	switch fmt {
+	case 'e', 'E':
+		return fmtE(dst, neg, digs, prec, fmt)
+	case 'f':
+		return fmtF(dst, neg, digs, prec)
+	case 'g', 'G':
+		// trailing fractional zeros in 'e' form will be trimmed.
+		eprec := prec
+		if eprec > digs.nd && digs.nd >= digs.dp {
+			eprec = digs.nd
+		}
+		// %e is used if the exponent from the conversion
+		// is less than -4 or greater than or equal to the precision.
+		// if precision was the shortest possible, use precision 6 for this decision.
+		if shortest {
+			eprec = 6
+		}
+		exp := digs.dp - 1
+		if exp < -4 || exp >= eprec {
+			if prec > digs.nd {
+				prec = digs.nd
+			}
+			return fmtE(dst, neg, digs, prec-1, fmt+'e'-'g')
+		}
+		if prec > digs.dp {
+			prec = digs.nd
+		}
+		return fmtF(dst, neg, digs, max(prec-digs.dp, 0))
+	}
+
+	// unknown format
+	return append(dst, '%', fmt)
+}
+
+// roundShortest rounds d (= mant * 2^exp) to the shortest number of digits
+// that will let the original floating point value be precisely reconstructed.
+func roundShortest(d *decimal, mant uint64, exp int, flt *floatInfo) {
+	// If mantissa is zero, the number is zero; stop now.
+	if mant == 0 {
+		d.nd = 0
+		return
+	}
+
+	// Compute upper and lower such that any decimal number
+	// between upper and lower (possibly inclusive)
+	// will round to the original floating point number.
+
+	// We may see at once that the number is already shortest.
+	//
+	// Suppose d is not denormal, so that 2^exp <= d < 10^dp.
+	// The closest shorter number is at least 10^(dp-nd) away.
+	// The lower/upper bounds computed below are at distance
+	// at most 2^(exp-mantbits).
+	//
+	// So the number is already shortest if 10^(dp-nd) > 2^(exp-mantbits),
+	// or equivalently log2(10)*(dp-nd) > exp-mantbits.
+	// It is true if 332/100*(dp-nd) >= exp-mantbits (log2(10) > 3.32).
+	minexp := flt.bias + 1 // minimum possible exponent
+	if exp > minexp && 332*(d.dp-d.nd) >= 100*(exp-int(flt.mantbits)) {
+		// The number is already shortest.
+		return
+	}
+
+	// d = mant << (exp - mantbits)
+	// Next highest floating point number is mant+1 << exp-mantbits.
+	// Our upper bound is halfway between, mant*2+1 << exp-mantbits-1.
+	upper := new(decimal)
+	upper.Assign(mant*2 + 1)
+	upper.Shift(exp - int(flt.mantbits) - 1)
+
+	// d = mant << (exp - mantbits)
+	// Next lowest floating point number is mant-1 << exp-mantbits,
+	// unless mant-1 drops the significant bit and exp is not the minimum exp,
+	// in which case the next lowest is mant*2-1 << exp-mantbits-1.
+	// Either way, call it mantlo << explo-mantbits.
+	// Our lower bound is halfway between, mantlo*2+1 << explo-mantbits-1.
+	var mantlo uint64
+	var explo int
+	if mant > 1<<flt.mantbits || exp == minexp {
+		mantlo = mant - 1
+		explo = exp
+	} else {
+		mantlo = mant*2 - 1
+		explo = exp - 1
+	}
+	lower := new(decimal)
+	lower.Assign(mantlo*2 + 1)
+	lower.Shift(explo - int(flt.mantbits) - 1)
+
+	// The upper and lower bounds are possible outputs only if
+	// the original mantissa is even, so that IEEE round-to-even
+	// would round to the original mantissa and not the neighbors.
+	inclusive := mant%2 == 0
+
+	// As we walk the digits we want to know whether rounding up would fall
+	// within the upper bound. This is tracked by upperdelta:
+	//
+	// If upperdelta == 0, the digits of d and upper are the same so far.
+	//
+	// If upperdelta == 1, we saw a difference of 1 between d and upper on a
+	// previous digit and subsequently only 9s for d and 0s for upper.
+	// (Thus rounding up may fall outside the bound, if it is exclusive.)
+	//
+	// If upperdelta == 2, then the difference is greater than 1
+	// and we know that rounding up falls within the bound.
+	var upperdelta uint8
+
+	// Now we can figure out the minimum number of digits required.
+	// Walk along until d has distinguished itself from upper and lower.
+	for ui := 0; ; ui++ {
+		// lower, d, and upper may have the decimal points at different
+		// places. In this case upper is the longest, so we iterate from
+		// ui==0 and start li and mi at (possibly) -1.
+		mi := ui - upper.dp + d.dp
+		if mi >= d.nd {
+			break
+		}
+		li := ui - upper.dp + lower.dp
+		l := byte('0') // lower digit
+		if li >= 0 && li < lower.nd {
+			l = lower.d[li]
+		}
+		m := byte('0') // middle digit
+		if mi >= 0 {
+			m = d.d[mi]
+		}
+		u := byte('0') // upper digit
+		if ui < upper.nd {
+			u = upper.d[ui]
+		}
+
+		// Okay to round down (truncate) if lower has a different digit
+		// or if lower is inclusive and is exactly the result of rounding
+		// down (i.e., and we have reached the final digit of lower).
+		okdown := l != m || inclusive && li+1 == lower.nd
+
+		switch {
+		case upperdelta == 0 && m+1 < u:
+			// Example:
+			// m = 12345xxx
+			// u = 12347xxx
+			upperdelta = 2
+		case upperdelta == 0 && m != u:
+			// Example:
+			// m = 12345xxx
+			// u = 12346xxx
+			upperdelta = 1
+		case upperdelta == 1 && (m != '9' || u != '0'):
+			// Example:
+			// m = 1234598x
+			// u = 1234600x
+			upperdelta = 2
+		}
+		// Okay to round up if upper has a different digit and either upper
+		// is inclusive or upper is bigger than the result of rounding up.
+		okup := upperdelta > 0 && (inclusive || upperdelta > 1 || ui+1 < upper.nd)
+
+		// If it's okay to do either, then round to the nearest one.
+		// If it's okay to do only one, do it.
+		switch {
+		case okdown && okup:
+			d.Round(mi + 1)
+			return
+		case okdown:
+			d.RoundDown(mi + 1)
+			return
+		case okup:
+			d.RoundUp(mi + 1)
+			return
+		}
+	}
+}
+
+type decimalSlice struct {
+	d      []byte
+	nd, dp int
+	neg    bool
+}
+
+// %e: -d.ddddde±dd
+func fmtE(dst []byte, neg bool, d decimalSlice, prec int, fmt byte) []byte {
+	// sign
+	if neg {
+		dst = append(dst, '-')
+	}
+
+	// first digit
+	ch := byte('0')
+	if d.nd != 0 {
+		ch = d.d[0]
+	}
+	dst = append(dst, ch)
+
+	// .moredigits
+	if prec > 0 {
+		dst = append(dst, '.')
+		i := 1
+		m := min(d.nd, prec+1)
+		if i < m {
+			dst = append(dst, d.d[i:m]...)
+			i = m
+		}
+		for ; i <= prec; i++ {
+			dst = append(dst, '0')
+		}
+	}
+
+	// e±
+	dst = append(dst, fmt)
+	exp := d.dp - 1
+	if d.nd == 0 { // special case: 0 has exponent 0
+		exp = 0
+	}
+	if exp < 0 {
+		ch = '-'
+		exp = -exp
+	} else {
+		ch = '+'
+	}
+	dst = append(dst, ch)
+
+	// dd or ddd
+	switch {
+	case exp < 10:
+		dst = append(dst, '0', byte(exp)+'0')
+	case exp < 100:
+		dst = append(dst, byte(exp/10)+'0', byte(exp%10)+'0')
+	default:
+		dst = append(dst, byte(exp/100)+'0', byte(exp/10)%10+'0', byte(exp%10)+'0')
+	}
+
+	return dst
+}
+
+// %f: -ddddddd.ddddd
+func fmtF(dst []byte, neg bool, d decimalSlice, prec int) []byte {
+	// sign
+	if neg {
+		dst = append(dst, '-')
+	}
+
+	// integer, padded with zeros as needed.
+	if d.dp > 0 {
+		m := min(d.nd, d.dp)
+		dst = append(dst, d.d[:m]...)
+		for ; m < d.dp; m++ {
+			dst = append(dst, '0')
+		}
+	} else {
+		dst = append(dst, '0')
+	}
+
+	// fraction
+	if prec > 0 {
+		dst = append(dst, '.')
+		for i := 0; i < prec; i++ {
+			ch := byte('0')
+			if j := d.dp + i; 0 <= j && j < d.nd {
+				ch = d.d[j]
+			}
+			dst = append(dst, ch)
+		}
+	}
+
+	return dst
+}
+
+// %b: -ddddddddp±ddd
+func fmtB(dst []byte, neg bool, mant uint64, exp int, flt *floatInfo) []byte {
+	// sign
+	if neg {
+		dst = append(dst, '-')
+	}
+
+	// mantissa
+	dst, _ = formatBits(dst, mant, 10, false, true)
+
+	// p
+	dst = append(dst, 'p')
+
+	// ±exponent
+	exp -= int(flt.mantbits)
+	if exp >= 0 {
+		dst = append(dst, '+')
+	}
+	dst, _ = formatBits(dst, uint64(exp), 10, exp < 0, true)
+
+	return dst
+}
+
+// %x: -0x1.yyyyyyyyp±ddd or -0x0p+0. (y is hex digit, d is decimal digit)
+func fmtX(dst []byte, prec int, fmt byte, neg bool, mant uint64, exp int, flt *floatInfo) []byte {
+	if mant == 0 {
+		exp = 0
+	}
+
+	// Shift digits so leading 1 (if any) is at bit 1<<60.
+	mant <<= 60 - flt.mantbits
+	for mant != 0 && mant&(1<<60) == 0 {
+		mant <<= 1
+		exp--
+	}
+
+	// Round if requested.
+	if prec >= 0 && prec < 15 {
+		shift := uint(prec * 4)
+		extra := (mant << shift) & (1<<60 - 1)
+		mant >>= 60 - shift
+		if extra|(mant&1) > 1<<59 {
+			mant++
+		}
+		mant <<= 60 - shift
+		if mant&(1<<61) != 0 {
+			// Wrapped around.
+			mant >>= 1
+			exp++
+		}
+	}
+
+	hex := lowerhex
+	if fmt == 'X' {
+		hex = upperhex
+	}
+
+	// sign, 0x, leading digit
+	if neg {
+		dst = append(dst, '-')
+	}
+	dst = append(dst, '0', fmt, '0'+byte((mant>>60)&1))
+
+	// .fraction
+	mant <<= 4 // remove leading 0 or 1
+	if prec < 0 && mant != 0 {
+		dst = append(dst, '.')
+		for mant != 0 {
+			dst = append(dst, hex[(mant>>60)&15])
+			mant <<= 4
+		}
+	} else if prec > 0 {
+		dst = append(dst, '.')
+		for i := 0; i < prec; i++ {
+			dst = append(dst, hex[(mant>>60)&15])
+			mant <<= 4
+		}
+	}
+
+	// p±
+	ch := byte('P')
+	if fmt == lower(fmt) {
+		ch = 'p'
+	}
+	dst = append(dst, ch)
+	if exp < 0 {
+		ch = '-'
+		exp = -exp
+	} else {
+		ch = '+'
+	}
+	dst = append(dst, ch)
+
+	// dd or ddd or dddd
+	switch {
+	case exp < 100:
+		dst = append(dst, byte(exp/10)+'0', byte(exp%10)+'0')
+	case exp < 1000:
+		dst = append(dst, byte(exp/100)+'0', byte((exp/10)%10)+'0', byte(exp%10)+'0')
+	default:
+		dst = append(dst, byte(exp/1000)+'0', byte(exp/100)%10+'0', byte((exp/10)%10)+'0', byte(exp%10)+'0')
+	}
+
+	return dst
+}
+
+func min(a, b int) int {
+	if a < b {
+		return a
+	}
+	return b
+}
+
+func max(a, b int) int {
+	if a > b {
+		return a
+	}
+	return b
+}
diff --git a/contrib/go/_std_1.19/src/strconv/ftoaryu.go b/contrib/go/_std_1.19/src/strconv/ftoaryu.go
new file mode 100644
index 0000000000..b975cdc9b9
--- /dev/null
+++ b/contrib/go/_std_1.19/src/strconv/ftoaryu.go
@@ -0,0 +1,569 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package strconv
+
+import (
+	"math/bits"
+)
+
+// binary to decimal conversion using the Ryū algorithm.
+//
+// See Ulf Adams, "Ryū: Fast Float-to-String Conversion" (doi:10.1145/3192366.3192369)
+//
+// Fixed precision formatting is a variant of the original paper's
+// algorithm, where a single multiplication by 10^k is required,
+// sharing the same rounding guarantees.
+
+// ryuFtoaFixed32 formats mant*(2^exp) with prec decimal digits.
+func ryuFtoaFixed32(d *decimalSlice, mant uint32, exp int, prec int) {
+	if prec < 0 {
+		panic("ryuFtoaFixed32 called with negative prec")
+	}
+	if prec > 9 {
+		panic("ryuFtoaFixed32 called with prec > 9")
+	}
+	// Zero input.
+	if mant == 0 {
+		d.nd, d.dp = 0, 0
+		return
+	}
+	// Renormalize to a 25-bit mantissa.
+	e2 := exp
+	if b := bits.Len32(mant); b < 25 {
+		mant <<= uint(25 - b)
+		e2 += int(b) - 25
+	}
+	// Choose an exponent such that rounded mant*(2^e2)*(10^q) has
+	// at least prec decimal digits, i.e
+	//     mant*(2^e2)*(10^q) >= 10^(prec-1)
+	// Because mant >= 2^24, it is enough to choose:
+	//     2^(e2+24) >= 10^(-q+prec-1)
+	// or q = -mulByLog2Log10(e2+24) + prec - 1
+	q := -mulByLog2Log10(e2+24) + prec - 1
+
+	// Now compute mant*(2^e2)*(10^q).
+	// Is it an exact computation?
+	// Only small positive powers of 10 are exact (5^28 has 66 bits).
+	exact := q <= 27 && q >= 0
+
+	di, dexp2, d0 := mult64bitPow10(mant, e2, q)
+	if dexp2 >= 0 {
+		panic("not enough significant bits after mult64bitPow10")
+	}
+	// As a special case, computation might still be exact, if exponent
+	// was negative and if it amounts to computing an exact division.
+	// In that case, we ignore all lower bits.
+	// Note that division by 10^11 cannot be exact as 5^11 has 26 bits.
+	if q < 0 && q >= -10 && divisibleByPower5(uint64(mant), -q) {
+		exact = true
+		d0 = true
+	}
+	// Remove extra lower bits and keep rounding info.
+	extra := uint(-dexp2)
+	extraMask := uint32(1<<extra - 1)
+
+	di, dfrac := di>>extra, di&extraMask
+	roundUp := false
+	if exact {
+		// If we computed an exact product, d + 1/2
+		// should round to d+1 if 'd' is odd.
+		roundUp = dfrac > 1<<(extra-1) ||
+			(dfrac == 1<<(extra-1) && !d0) ||
+			(dfrac == 1<<(extra-1) && d0 && di&1 == 1)
+	} else {
+		// otherwise, d+1/2 always rounds up because
+		// we truncated below.
+		roundUp = dfrac>>(extra-1) == 1
+	}
+	if dfrac != 0 {
+		d0 = false
+	}
+	// Proceed to the requested number of digits
+	formatDecimal(d, uint64(di), !d0, roundUp, prec)
+	// Adjust exponent
+	d.dp -= q
+}
+
+// ryuFtoaFixed64 formats mant*(2^exp) with prec decimal digits.
+func ryuFtoaFixed64(d *decimalSlice, mant uint64, exp int, prec int) {
+	if prec > 18 {
+		panic("ryuFtoaFixed64 called with prec > 18")
+	}
+	// Zero input.
+	if mant == 0 {
+		d.nd, d.dp = 0, 0
+		return
+	}
+	// Renormalize to a 55-bit mantissa.
+	e2 := exp
+	if b := bits.Len64(mant); b < 55 {
+		mant = mant << uint(55-b)
+		e2 += int(b) - 55
+	}
+	// Choose an exponent such that rounded mant*(2^e2)*(10^q) has
+	// at least prec decimal digits, i.e
+	//     mant*(2^e2)*(10^q) >= 10^(prec-1)
+	// Because mant >= 2^54, it is enough to choose:
+	//     2^(e2+54) >= 10^(-q+prec-1)
+	// or q = -mulByLog2Log10(e2+54) + prec - 1
+	//
+	// The minimal required exponent is -mulByLog2Log10(1025)+18 = -291
+	// The maximal required exponent is mulByLog2Log10(1074)+18 = 342
+	q := -mulByLog2Log10(e2+54) + prec - 1
+
+	// Now compute mant*(2^e2)*(10^q).
+	// Is it an exact computation?
+	// Only small positive powers of 10 are exact (5^55 has 128 bits).
+	exact := q <= 55 && q >= 0
+
+	di, dexp2, d0 := mult128bitPow10(mant, e2, q)
+	if dexp2 >= 0 {
+		panic("not enough significant bits after mult128bitPow10")
+	}
+	// As a special case, computation might still be exact, if exponent
+	// was negative and if it amounts to computing an exact division.
+	// In that case, we ignore all lower bits.
+	// Note that division by 10^23 cannot be exact as 5^23 has 54 bits.
+	if q < 0 && q >= -22 && divisibleByPower5(mant, -q) {
+		exact = true
+		d0 = true
+	}
+	// Remove extra lower bits and keep rounding info.
+	extra := uint(-dexp2)
+	extraMask := uint64(1<<extra - 1)
+
+	di, dfrac := di>>extra, di&extraMask
+	roundUp := false
+	if exact {
+		// If we computed an exact product, d + 1/2
+		// should round to d+1 if 'd' is odd.
+		roundUp = dfrac > 1<<(extra-1) ||
+			(dfrac == 1<<(extra-1) && !d0) ||
+			(dfrac == 1<<(extra-1) && d0 && di&1 == 1)
+	} else {
+		// otherwise, d+1/2 always rounds up because
+		// we truncated below.
+		roundUp = dfrac>>(extra-1) == 1
+	}
+	if dfrac != 0 {
+		d0 = false
+	}
+	// Proceed to the requested number of digits
+	formatDecimal(d, di, !d0, roundUp, prec)
+	// Adjust exponent
+	d.dp -= q
+}
+
+var uint64pow10 = [...]uint64{
+	1, 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9,
+	1e10, 1e11, 1e12, 1e13, 1e14, 1e15, 1e16, 1e17, 1e18, 1e19,
+}
+
+// formatDecimal fills d with at most prec decimal digits
+// of mantissa m. The boolean trunc indicates whether m
+// is truncated compared to the original number being formatted.
+func formatDecimal(d *decimalSlice, m uint64, trunc bool, roundUp bool, prec int) {
+	max := uint64pow10[prec]
+	trimmed := 0
+	for m >= max {
+		a, b := m/10, m%10
+		m = a
+		trimmed++
+		if b > 5 {
+			roundUp = true
+		} else if b < 5 {
+			roundUp = false
+		} else { // b == 5
+			// round up if there are trailing digits,
+			// or if the new value of m is odd (round-to-even convention)
+			roundUp = trunc || m&1 == 1
+		}
+		if b != 0 {
+			trunc = true
+		}
+	}
+	if roundUp {
+		m++
+	}
+	if m >= max {
+		// Happens if di was originally 99999....xx
+		m /= 10
+		trimmed++
+	}
+	// render digits (similar to formatBits)
+	n := uint(prec)
+	d.nd = int(prec)
+	v := m
+	for v >= 100 {
+		var v1, v2 uint64
+		if v>>32 == 0 {
+			v1, v2 = uint64(uint32(v)/100), uint64(uint32(v)%100)
+		} else {
+			v1, v2 = v/100, v%100
+		}
+		n -= 2
+		d.d[n+1] = smallsString[2*v2+1]
+		d.d[n+0] = smallsString[2*v2+0]
+		v = v1
+	}
+	if v > 0 {
+		n--
+		d.d[n] = smallsString[2*v+1]
+	}
+	if v >= 10 {
+		n--
+		d.d[n] = smallsString[2*v]
+	}
+	for d.d[d.nd-1] == '0' {
+		d.nd--
+		trimmed++
+	}
+	d.dp = d.nd + trimmed
+}
+
+// ryuFtoaShortest formats mant*2^exp with prec decimal digits.
+func ryuFtoaShortest(d *decimalSlice, mant uint64, exp int, flt *floatInfo) {
+	if mant == 0 {
+		d.nd, d.dp = 0, 0
+		return
+	}
+	// If input is an exact integer with fewer bits than the mantissa,
+	// the previous and next integer are not admissible representations.
+	if exp <= 0 && bits.TrailingZeros64(mant) >= -exp {
+		mant >>= uint(-exp)
+		ryuDigits(d, mant, mant, mant, true, false)
+		return
+	}
+	ml, mc, mu, e2 := computeBounds(mant, exp, flt)
+	if e2 == 0 {
+		ryuDigits(d, ml, mc, mu, true, false)
+		return
+	}
+	// Find 10^q *larger* than 2^-e2
+	q := mulByLog2Log10(-e2) + 1
+
+	// We are going to multiply by 10^q using 128-bit arithmetic.
+	// The exponent is the same for all 3 numbers.
+	var dl, dc, du uint64
+	var dl0, dc0, du0 bool
+	if flt == &float32info {
+		var dl32, dc32, du32 uint32
+		dl32, _, dl0 = mult64bitPow10(uint32(ml), e2, q)
+		dc32, _, dc0 = mult64bitPow10(uint32(mc), e2, q)
+		du32, e2, du0 = mult64bitPow10(uint32(mu), e2, q)
+		dl, dc, du = uint64(dl32), uint64(dc32), uint64(du32)
+	} else {
+		dl, _, dl0 = mult128bitPow10(ml, e2, q)
+		dc, _, dc0 = mult128bitPow10(mc, e2, q)
+		du, e2, du0 = mult128bitPow10(mu, e2, q)
+	}
+	if e2 >= 0 {
+		panic("not enough significant bits after mult128bitPow10")
+	}
+	// Is it an exact computation?
+	if q > 55 {
+		// Large positive powers of ten are not exact
+		dl0, dc0, du0 = false, false, false
+	}
+	if q < 0 && q >= -24 {
+		// Division by a power of ten may be exact.
+		// (note that 5^25 is a 59-bit number so division by 5^25 is never exact).
+		if divisibleByPower5(ml, -q) {
+			dl0 = true
+		}
+		if divisibleByPower5(mc, -q) {
+			dc0 = true
+		}
+		if divisibleByPower5(mu, -q) {
+			du0 = true
+		}
+	}
+	// Express the results (dl, dc, du)*2^e2 as integers.
+	// Extra bits must be removed and rounding hints computed.
+	extra := uint(-e2)
+	extraMask := uint64(1<<extra - 1)
+	// Now compute the floored, integral base 10 mantissas.
+	dl, fracl := dl>>extra, dl&extraMask
+	dc, fracc := dc>>extra, dc&extraMask
+	du, fracu := du>>extra, du&extraMask
+	// Is it allowed to use 'du' as a result?
+	// It is always allowed when it is truncated, but also
+	// if it is exact and the original binary mantissa is even
+	// When disallowed, we can subtract 1.
+	uok := !du0 || fracu > 0
+	if du0 && fracu == 0 {
+		uok = mant&1 == 0
+	}
+	if !uok {
+		du--
+	}
+	// Is 'dc' the correctly rounded base 10 mantissa?
+	// The correct rounding might be dc+1
+	cup := false // don't round up.
+	if dc0 {
+		// If we computed an exact product, the half integer
+		// should round to next (even) integer if 'dc' is odd.
+		cup = fracc > 1<<(extra-1) ||
+			(fracc == 1<<(extra-1) && dc&1 == 1)
+	} else {
+		// otherwise, the result is a lower truncation of the ideal
+		// result.
+		cup = fracc>>(extra-1) == 1
+	}
+	// Is 'dl' an allowed representation?
+	// Only if it is an exact value, and if the original binary mantissa
+	// was even.
+	lok := dl0 && fracl == 0 && (mant&1 == 0)
+	if !lok {
+		dl++
+	}
+	// We need to remember whether the trimmed digits of 'dc' are zero.
+	c0 := dc0 && fracc == 0
+	// render digits
+	ryuDigits(d, dl, dc, du, c0, cup)
+	d.dp -= q
+}
+
+// mulByLog2Log10 returns math.Floor(x * log(2)/log(10)) for an integer x in
+// the range -1600 <= x && x <= +1600.
+//
+// The range restriction lets us work in faster integer arithmetic instead of
+// slower floating point arithmetic. Correctness is verified by unit tests.
+func mulByLog2Log10(x int) int {
+	// log(2)/log(10) ≈ 0.30102999566 ≈ 78913 / 2^18
+	return (x * 78913) >> 18
+}
+
+// mulByLog10Log2 returns math.Floor(x * log(10)/log(2)) for an integer x in
+// the range -500 <= x && x <= +500.
+//
+// The range restriction lets us work in faster integer arithmetic instead of
+// slower floating point arithmetic. Correctness is verified by unit tests.
+func mulByLog10Log2(x int) int {
+	// log(10)/log(2) ≈ 3.32192809489 ≈ 108853 / 2^15
+	return (x * 108853) >> 15
+}
+
+// computeBounds returns a floating-point vector (l, c, u)×2^e2
+// where the mantissas are 55-bit (or 26-bit) integers, describing the interval
+// represented by the input float64 or float32.
+func computeBounds(mant uint64, exp int, flt *floatInfo) (lower, central, upper uint64, e2 int) {
+	if mant != 1<<flt.mantbits || exp == flt.bias+1-int(flt.mantbits) {
+		// regular case (or denormals)
+		lower, central, upper = 2*mant-1, 2*mant, 2*mant+1
+		e2 = exp - 1
+		return
+	} else {
+		// border of an exponent
+		lower, central, upper = 4*mant-1, 4*mant, 4*mant+2
+		e2 = exp - 2
+		return
+	}
+}
+
+func ryuDigits(d *decimalSlice, lower, central, upper uint64,
+	c0, cup bool) {
+	lhi, llo := divmod1e9(lower)
+	chi, clo := divmod1e9(central)
+	uhi, ulo := divmod1e9(upper)
+	if uhi == 0 {
+		// only low digits (for denormals)
+		ryuDigits32(d, llo, clo, ulo, c0, cup, 8)
+	} else if lhi < uhi {
+		// truncate 9 digits at once.
+		if llo != 0 {
+			lhi++
+		}
+		c0 = c0 && clo == 0
+		cup = (clo > 5e8) || (clo == 5e8 && cup)
+		ryuDigits32(d, lhi, chi, uhi, c0, cup, 8)
+		d.dp += 9
+	} else {
+		d.nd = 0
+		// emit high part
+		n := uint(9)
+		for v := chi; v > 0; {
+			v1, v2 := v/10, v%10
+			v = v1
+			n--
+			d.d[n] = byte(v2 + '0')
+		}
+		d.d = d.d[n:]
+		d.nd = int(9 - n)
+		// emit low part
+		ryuDigits32(d, llo, clo, ulo,
+			c0, cup, d.nd+8)
+	}
+	// trim trailing zeros
+	for d.nd > 0 && d.d[d.nd-1] == '0' {
+		d.nd--
+	}
+	// trim initial zeros
+	for d.nd > 0 && d.d[0] == '0' {
+		d.nd--
+		d.dp--
+		d.d = d.d[1:]
+	}
+}
+
+// ryuDigits32 emits decimal digits for a number less than 1e9.
+func ryuDigits32(d *decimalSlice, lower, central, upper uint32,
+	c0, cup bool, endindex int) {
+	if upper == 0 {
+		d.dp = endindex + 1
+		return
+	}
+	trimmed := 0
+	// Remember last trimmed digit to check for round-up.
+	// c0 will be used to remember zeroness of following digits.
+	cNextDigit := 0
+	for upper > 0 {
+		// Repeatedly compute:
+		// l = Ceil(lower / 10^k)
+		// c = Round(central / 10^k)
+		// u = Floor(upper / 10^k)
+		// and stop when c goes out of the (l, u) interval.
+		l := (lower + 9) / 10
+		c, cdigit := central/10, central%10
+		u := upper / 10
+		if l > u {
+			// don't trim the last digit as it is forbidden to go below l
+			// other, trim and exit now.
+			break
+		}
+		// Check that we didn't cross the lower boundary.
+		// The case where l < u but c == l-1 is essentially impossible,
+		// but may happen if:
+		//    lower   = ..11
+		//    central = ..19
+		//    upper   = ..31
+		// and means that 'central' is very close but less than
+		// an integer ending with many zeros, and usually
+		// the "round-up" logic hides the problem.
+		if l == c+1 && c < u {
+			c++
+			cdigit = 0
+			cup = false
+		}
+		trimmed++
+		// Remember trimmed digits of c
+		c0 = c0 && cNextDigit == 0
+		cNextDigit = int(cdigit)
+		lower, central, upper = l, c, u
+	}
+	// should we round up?
+	if trimmed > 0 {
+		cup = cNextDigit > 5 ||
+			(cNextDigit == 5 && !c0) ||
+			(cNextDigit == 5 && c0 && central&1 == 1)
+	}
+	if central < upper && cup {
+		central++
+	}
+	// We know where the number ends, fill directly
+	endindex -= trimmed
+	v := central
+	n := endindex
+	for n > d.nd {
+		v1, v2 := v/100, v%100
+		d.d[n] = smallsString[2*v2+1]
+		d.d[n-1] = smallsString[2*v2+0]
+		n -= 2
+		v = v1
+	}
+	if n == d.nd {
+		d.d[n] = byte(v + '0')
+	}
+	d.nd = endindex + 1
+	d.dp = d.nd + trimmed
+}
+
+// mult64bitPow10 takes a floating-point input with a 25-bit
+// mantissa and multiplies it with 10^q. The resulting mantissa
+// is m*P >> 57 where P is a 64-bit element of the detailedPowersOfTen tables.
+// It is typically 31 or 32-bit wide.
+// The returned boolean is true if all trimmed bits were zero.
+//
+// That is:
+//
+//	m*2^e2 * round(10^q) = resM * 2^resE + ε
+//	exact = ε == 0
+func mult64bitPow10(m uint32, e2, q int) (resM uint32, resE int, exact bool) {
+	if q == 0 {
+		// P == 1<<63
+		return m << 6, e2 - 6, true
+	}
+	if q < detailedPowersOfTenMinExp10 || detailedPowersOfTenMaxExp10 < q {
+		// This never happens due to the range of float32/float64 exponent
+		panic("mult64bitPow10: power of 10 is out of range")
+	}
+	pow := detailedPowersOfTen[q-detailedPowersOfTenMinExp10][1]
+	if q < 0 {
+		// Inverse powers of ten must be rounded up.
+		pow += 1
+	}
+	hi, lo := bits.Mul64(uint64(m), pow)
+	e2 += mulByLog10Log2(q) - 63 + 57
+	return uint32(hi<<7 | lo>>57), e2, lo<<7 == 0
+}
+
+// mult128bitPow10 takes a floating-point input with a 55-bit
+// mantissa and multiplies it with 10^q. The resulting mantissa
+// is m*P >> 119 where P is a 128-bit element of the detailedPowersOfTen tables.
+// It is typically 63 or 64-bit wide.
+// The returned boolean is true is all trimmed bits were zero.
+//
+// That is:
+//
+//	m*2^e2 * round(10^q) = resM * 2^resE + ε
+//	exact = ε == 0
+func mult128bitPow10(m uint64, e2, q int) (resM uint64, resE int, exact bool) {
+	if q == 0 {
+		// P == 1<<127
+		return m << 8, e2 - 8, true
+	}
+	if q < detailedPowersOfTenMinExp10 || detailedPowersOfTenMaxExp10 < q {
+		// This never happens due to the range of float32/float64 exponent
+		panic("mult128bitPow10: power of 10 is out of range")
+	}
+	pow := detailedPowersOfTen[q-detailedPowersOfTenMinExp10]
+	if q < 0 {
+		// Inverse powers of ten must be rounded up.
+		pow[0] += 1
+	}
+	e2 += mulByLog10Log2(q) - 127 + 119
+
+	// long multiplication
+	l1, l0 := bits.Mul64(m, pow[0])
+	h1, h0 := bits.Mul64(m, pow[1])
+	mid, carry := bits.Add64(l1, h0, 0)
+	h1 += carry
+	return h1<<9 | mid>>55, e2, mid<<9 == 0 && l0 == 0
+}
+
+func divisibleByPower5(m uint64, k int) bool {
+	if m == 0 {
+		return true
+	}
+	for i := 0; i < k; i++ {
+		if m%5 != 0 {
+			return false
+		}
+		m /= 5
+	}
+	return true
+}
+
+// divmod1e9 computes quotient and remainder of division by 1e9,
+// avoiding runtime uint64 division on 32-bit platforms.
+func divmod1e9(x uint64) (uint32, uint32) {
+	if !host32bit {
+		return uint32(x / 1e9), uint32(x % 1e9)
+	}
+	// Use the same sequence of operations as the amd64 compiler.
+	hi, _ := bits.Mul64(x>>1, 0x89705f4136b4a598) // binary digits of 1e-9
+	q := hi >> 28
+	return uint32(q), uint32(x - q*1e9)
+}
diff --git a/contrib/go/_std_1.18/src/strconv/isprint.go b/contrib/go/_std_1.19/src/strconv/isprint.go
index 994a8e423c..994a8e423c 100644
--- a/contrib/go/_std_1.18/src/strconv/isprint.go
+++ b/contrib/go/_std_1.19/src/strconv/isprint.go
diff --git a/contrib/go/_std_1.19/src/strconv/itoa.go b/contrib/go/_std_1.19/src/strconv/itoa.go
new file mode 100644
index 0000000000..b0c2666e7c
--- /dev/null
+++ b/contrib/go/_std_1.19/src/strconv/itoa.go
@@ -0,0 +1,205 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package strconv
+
+import "math/bits"
+
+const fastSmalls = true // enable fast path for small integers
+
+// FormatUint returns the string representation of i in the given base,
+// for 2 <= base <= 36. The result uses the lower-case letters 'a' to 'z'
+// for digit values >= 10.
+func FormatUint(i uint64, base int) string {
+	if fastSmalls && i < nSmalls && base == 10 {
+		return small(int(i))
+	}
+	_, s := formatBits(nil, i, base, false, false)
+	return s
+}
+
+// FormatInt returns the string representation of i in the given base,
+// for 2 <= base <= 36. The result uses the lower-case letters 'a' to 'z'
+// for digit values >= 10.
+func FormatInt(i int64, base int) string {
+	if fastSmalls && 0 <= i && i < nSmalls && base == 10 {
+		return small(int(i))
+	}
+	_, s := formatBits(nil, uint64(i), base, i < 0, false)
+	return s
+}
+
+// Itoa is equivalent to FormatInt(int64(i), 10).
+func Itoa(i int) string {
+	return FormatInt(int64(i), 10)
+}
+
+// AppendInt appends the string form of the integer i,
+// as generated by FormatInt, to dst and returns the extended buffer.
+func AppendInt(dst []byte, i int64, base int) []byte {
+	if fastSmalls && 0 <= i && i < nSmalls && base == 10 {
+		return append(dst, small(int(i))...)
+	}
+	dst, _ = formatBits(dst, uint64(i), base, i < 0, true)
+	return dst
+}
+
+// AppendUint appends the string form of the unsigned integer i,
+// as generated by FormatUint, to dst and returns the extended buffer.
+func AppendUint(dst []byte, i uint64, base int) []byte {
+	if fastSmalls && i < nSmalls && base == 10 {
+		return append(dst, small(int(i))...)
+	}
+	dst, _ = formatBits(dst, i, base, false, true)
+	return dst
+}
+
+// small returns the string for an i with 0 <= i < nSmalls.
+func small(i int) string {
+	if i < 10 {
+		return digits[i : i+1]
+	}
+	return smallsString[i*2 : i*2+2]
+}
+
+const nSmalls = 100
+
+const smallsString = "00010203040506070809" +
+	"10111213141516171819" +
+	"20212223242526272829" +
+	"30313233343536373839" +
+	"40414243444546474849" +
+	"50515253545556575859" +
+	"60616263646566676869" +
+	"70717273747576777879" +
+	"80818283848586878889" +
+	"90919293949596979899"
+
+const host32bit = ^uint(0)>>32 == 0
+
+const digits = "0123456789abcdefghijklmnopqrstuvwxyz"
+
+// formatBits computes the string representation of u in the given base.
+// If neg is set, u is treated as negative int64 value. If append_ is
+// set, the string is appended to dst and the resulting byte slice is
+// returned as the first result value; otherwise the string is returned
+// as the second result value.
+func formatBits(dst []byte, u uint64, base int, neg, append_ bool) (d []byte, s string) {
+	if base < 2 || base > len(digits) {
+		panic("strconv: illegal AppendInt/FormatInt base")
+	}
+	// 2 <= base && base <= len(digits)
+
+	var a [64 + 1]byte // +1 for sign of 64bit value in base 2
+	i := len(a)
+
+	if neg {
+		u = -u
+	}
+
+	// convert bits
+	// We use uint values where we can because those will
+	// fit into a single register even on a 32bit machine.
+	if base == 10 {
+		// common case: use constants for / because
+		// the compiler can optimize it into a multiply+shift
+
+		if host32bit {
+			// convert the lower digits using 32bit operations
+			for u >= 1e9 {
+				// Avoid using r = a%b in addition to q = a/b
+				// since 64bit division and modulo operations
+				// are calculated by runtime functions on 32bit machines.
+				q := u / 1e9
+				us := uint(u - q*1e9) // u % 1e9 fits into a uint
+				for j := 4; j > 0; j-- {
+					is := us % 100 * 2
+					us /= 100
+					i -= 2
+					a[i+1] = smallsString[is+1]
+					a[i+0] = smallsString[is+0]
+				}
+
+				// us < 10, since it contains the last digit
+				// from the initial 9-digit us.
+				i--
+				a[i] = smallsString[us*2+1]
+
+				u = q
+			}
+			// u < 1e9
+		}
+
+		// u guaranteed to fit into a uint
+		us := uint(u)
+		for us >= 100 {
+			is := us % 100 * 2
+			us /= 100
+			i -= 2
+			a[i+1] = smallsString[is+1]
+			a[i+0] = smallsString[is+0]
+		}
+
+		// us < 100
+		is := us * 2
+		i--
+		a[i] = smallsString[is+1]
+		if us >= 10 {
+			i--
+			a[i] = smallsString[is]
+		}
+
+	} else if isPowerOfTwo(base) {
+		// Use shifts and masks instead of / and %.
+		// Base is a power of 2 and 2 <= base <= len(digits) where len(digits) is 36.
+		// The largest power of 2 below or equal to 36 is 32, which is 1 << 5;
+		// i.e., the largest possible shift count is 5. By &-ind that value with
+		// the constant 7 we tell the compiler that the shift count is always
+		// less than 8 which is smaller than any register width. This allows
+		// the compiler to generate better code for the shift operation.
+		shift := uint(bits.TrailingZeros(uint(base))) & 7
+		b := uint64(base)
+		m := uint(base) - 1 // == 1<<shift - 1
+		for u >= b {
+			i--
+			a[i] = digits[uint(u)&m]
+			u >>= shift
+		}
+		// u < base
+		i--
+		a[i] = digits[uint(u)]
+	} else {
+		// general case
+		b := uint64(base)
+		for u >= b {
+			i--
+			// Avoid using r = a%b in addition to q = a/b
+			// since 64bit division and modulo operations
+			// are calculated by runtime functions on 32bit machines.
+			q := u / b
+			a[i] = digits[uint(u-q*b)]
+			u = q
+		}
+		// u < base
+		i--
+		a[i] = digits[uint(u)]
+	}
+
+	// add sign, if any
+	if neg {
+		i--
+		a[i] = '-'
+	}
+
+	if append_ {
+		d = append(dst, a[i:]...)
+		return
+	}
+	s = string(a[i:])
+	return
+}
+
+func isPowerOfTwo(x int) bool {
+	return x&(x-1) == 0
+}
diff --git a/contrib/go/_std_1.19/src/strconv/quote.go b/contrib/go/_std_1.19/src/strconv/quote.go
new file mode 100644
index 0000000000..1b5bddfeae
--- /dev/null
+++ b/contrib/go/_std_1.19/src/strconv/quote.go
@@ -0,0 +1,604 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:generate go run makeisprint.go -output isprint.go
+
+package strconv
+
+import (
+	"unicode/utf8"
+)
+
+const (
+	lowerhex = "0123456789abcdef"
+	upperhex = "0123456789ABCDEF"
+)
+
+// contains reports whether the string contains the byte c.
+func contains(s string, c byte) bool {
+	return index(s, c) != -1
+}
+
+func quoteWith(s string, quote byte, ASCIIonly, graphicOnly bool) string {
+	return string(appendQuotedWith(make([]byte, 0, 3*len(s)/2), s, quote, ASCIIonly, graphicOnly))
+}
+
+func quoteRuneWith(r rune, quote byte, ASCIIonly, graphicOnly bool) string {
+	return string(appendQuotedRuneWith(nil, r, quote, ASCIIonly, graphicOnly))
+}
+
+func appendQuotedWith(buf []byte, s string, quote byte, ASCIIonly, graphicOnly bool) []byte {
+	// Often called with big strings, so preallocate. If there's quoting,
+	// this is conservative but still helps a lot.
+	if cap(buf)-len(buf) < len(s) {
+		nBuf := make([]byte, len(buf), len(buf)+1+len(s)+1)
+		copy(nBuf, buf)
+		buf = nBuf
+	}
+	buf = append(buf, quote)
+	for width := 0; len(s) > 0; s = s[width:] {
+		r := rune(s[0])
+		width = 1
+		if r >= utf8.RuneSelf {
+			r, width = utf8.DecodeRuneInString(s)
+		}
+		if width == 1 && r == utf8.RuneError {
+			buf = append(buf, `\x`...)
+			buf = append(buf, lowerhex[s[0]>>4])
+			buf = append(buf, lowerhex[s[0]&0xF])
+			continue
+		}
+		buf = appendEscapedRune(buf, r, quote, ASCIIonly, graphicOnly)
+	}
+	buf = append(buf, quote)
+	return buf
+}
+
+func appendQuotedRuneWith(buf []byte, r rune, quote byte, ASCIIonly, graphicOnly bool) []byte {
+	buf = append(buf, quote)
+	if !utf8.ValidRune(r) {
+		r = utf8.RuneError
+	}
+	buf = appendEscapedRune(buf, r, quote, ASCIIonly, graphicOnly)
+	buf = append(buf, quote)
+	return buf
+}
+
+func appendEscapedRune(buf []byte, r rune, quote byte, ASCIIonly, graphicOnly bool) []byte {
+	var runeTmp [utf8.UTFMax]byte
+	if r == rune(quote) || r == '\\' { // always backslashed
+		buf = append(buf, '\\')
+		buf = append(buf, byte(r))
+		return buf
+	}
+	if ASCIIonly {
+		if r < utf8.RuneSelf && IsPrint(r) {
+			buf = append(buf, byte(r))
+			return buf
+		}
+	} else if IsPrint(r) || graphicOnly && isInGraphicList(r) {
+		n := utf8.EncodeRune(runeTmp[:], r)
+		buf = append(buf, runeTmp[:n]...)
+		return buf
+	}
+	switch r {
+	case '\a':
+		buf = append(buf, `\a`...)
+	case '\b':
+		buf = append(buf, `\b`...)
+	case '\f':
+		buf = append(buf, `\f`...)
+	case '\n':
+		buf = append(buf, `\n`...)
+	case '\r':
+		buf = append(buf, `\r`...)
+	case '\t':
+		buf = append(buf, `\t`...)
+	case '\v':
+		buf = append(buf, `\v`...)
+	default:
+		switch {
+		case r < ' ' || r == 0x7f:
+			buf = append(buf, `\x`...)
+			buf = append(buf, lowerhex[byte(r)>>4])
+			buf = append(buf, lowerhex[byte(r)&0xF])
+		case !utf8.ValidRune(r):
+			r = 0xFFFD
+			fallthrough
+		case r < 0x10000:
+			buf = append(buf, `\u`...)
+			for s := 12; s >= 0; s -= 4 {
+				buf = append(buf, lowerhex[r>>uint(s)&0xF])
+			}
+		default:
+			buf = append(buf, `\U`...)
+			for s := 28; s >= 0; s -= 4 {
+				buf = append(buf, lowerhex[r>>uint(s)&0xF])
+			}
+		}
+	}
+	return buf
+}
+
+// Quote returns a double-quoted Go string literal representing s. The
+// returned string uses Go escape sequences (\t, \n, \xFF, \u0100) for
+// control characters and non-printable characters as defined by
+// IsPrint.
+func Quote(s string) string {
+	return quoteWith(s, '"', false, false)
+}
+
+// AppendQuote appends a double-quoted Go string literal representing s,
+// as generated by Quote, to dst and returns the extended buffer.
+func AppendQuote(dst []byte, s string) []byte {
+	return appendQuotedWith(dst, s, '"', false, false)
+}
+
+// QuoteToASCII returns a double-quoted Go string literal representing s.
+// The returned string uses Go escape sequences (\t, \n, \xFF, \u0100) for
+// non-ASCII characters and non-printable characters as defined by IsPrint.
+func QuoteToASCII(s string) string {
+	return quoteWith(s, '"', true, false)
+}
+
+// AppendQuoteToASCII appends a double-quoted Go string literal representing s,
+// as generated by QuoteToASCII, to dst and returns the extended buffer.
+func AppendQuoteToASCII(dst []byte, s string) []byte {
+	return appendQuotedWith(dst, s, '"', true, false)
+}
+
+// QuoteToGraphic returns a double-quoted Go string literal representing s.
+// The returned string leaves Unicode graphic characters, as defined by
+// IsGraphic, unchanged and uses Go escape sequences (\t, \n, \xFF, \u0100)
+// for non-graphic characters.
+func QuoteToGraphic(s string) string {
+	return quoteWith(s, '"', false, true)
+}
+
+// AppendQuoteToGraphic appends a double-quoted Go string literal representing s,
+// as generated by QuoteToGraphic, to dst and returns the extended buffer.
+func AppendQuoteToGraphic(dst []byte, s string) []byte {
+	return appendQuotedWith(dst, s, '"', false, true)
+}
+
+// QuoteRune returns a single-quoted Go character literal representing the
+// rune. The returned string uses Go escape sequences (\t, \n, \xFF, \u0100)
+// for control characters and non-printable characters as defined by IsPrint.
+// If r is not a valid Unicode code point, it is interpreted as the Unicode
+// replacement character U+FFFD.
+func QuoteRune(r rune) string {
+	return quoteRuneWith(r, '\'', false, false)
+}
+
+// AppendQuoteRune appends a single-quoted Go character literal representing the rune,
+// as generated by QuoteRune, to dst and returns the extended buffer.
+func AppendQuoteRune(dst []byte, r rune) []byte {
+	return appendQuotedRuneWith(dst, r, '\'', false, false)
+}
+
+// QuoteRuneToASCII returns a single-quoted Go character literal representing
+// the rune. The returned string uses Go escape sequences (\t, \n, \xFF,
+// \u0100) for non-ASCII characters and non-printable characters as defined
+// by IsPrint.
+// If r is not a valid Unicode code point, it is interpreted as the Unicode
+// replacement character U+FFFD.
+func QuoteRuneToASCII(r rune) string {
+	return quoteRuneWith(r, '\'', true, false)
+}
+
+// AppendQuoteRuneToASCII appends a single-quoted Go character literal representing the rune,
+// as generated by QuoteRuneToASCII, to dst and returns the extended buffer.
+func AppendQuoteRuneToASCII(dst []byte, r rune) []byte {
+	return appendQuotedRuneWith(dst, r, '\'', true, false)
+}
+
+// QuoteRuneToGraphic returns a single-quoted Go character literal representing
+// the rune. If the rune is not a Unicode graphic character,
+// as defined by IsGraphic, the returned string will use a Go escape sequence
+// (\t, \n, \xFF, \u0100).
+// If r is not a valid Unicode code point, it is interpreted as the Unicode
+// replacement character U+FFFD.
+func QuoteRuneToGraphic(r rune) string {
+	return quoteRuneWith(r, '\'', false, true)
+}
+
+// AppendQuoteRuneToGraphic appends a single-quoted Go character literal representing the rune,
+// as generated by QuoteRuneToGraphic, to dst and returns the extended buffer.
+func AppendQuoteRuneToGraphic(dst []byte, r rune) []byte {
+	return appendQuotedRuneWith(dst, r, '\'', false, true)
+}
+
+// CanBackquote reports whether the string s can be represented
+// unchanged as a single-line backquoted string without control
+// characters other than tab.
+func CanBackquote(s string) bool {
+	for len(s) > 0 {
+		r, wid := utf8.DecodeRuneInString(s)
+		s = s[wid:]
+		if wid > 1 {
+			if r == '\ufeff' {
+				return false // BOMs are invisible and should not be quoted.
+			}
+			continue // All other multibyte runes are correctly encoded and assumed printable.
+		}
+		if r == utf8.RuneError {
+			return false
+		}
+		if (r < ' ' && r != '\t') || r == '`' || r == '\u007F' {
+			return false
+		}
+	}
+	return true
+}
+
+func unhex(b byte) (v rune, ok bool) {
+	c := rune(b)
+	switch {
+	case '0' <= c && c <= '9':
+		return c - '0', true
+	case 'a' <= c && c <= 'f':
+		return c - 'a' + 10, true
+	case 'A' <= c && c <= 'F':
+		return c - 'A' + 10, true
+	}
+	return
+}
+
+// UnquoteChar decodes the first character or byte in the escaped string
+// or character literal represented by the string s.
+// It returns four values:
+//
+//  1. value, the decoded Unicode code point or byte value;
+//  2. multibyte, a boolean indicating whether the decoded character requires a multibyte UTF-8 representation;
+//  3. tail, the remainder of the string after the character; and
+//  4. an error that will be nil if the character is syntactically valid.
+//
+// The second argument, quote, specifies the type of literal being parsed
+// and therefore which escaped quote character is permitted.
+// If set to a single quote, it permits the sequence \' and disallows unescaped '.
+// If set to a double quote, it permits \" and disallows unescaped ".
+// If set to zero, it does not permit either escape and allows both quote characters to appear unescaped.
+func UnquoteChar(s string, quote byte) (value rune, multibyte bool, tail string, err error) {
+	// easy cases
+	if len(s) == 0 {
+		err = ErrSyntax
+		return
+	}
+	switch c := s[0]; {
+	case c == quote && (quote == '\'' || quote == '"'):
+		err = ErrSyntax
+		return
+	case c >= utf8.RuneSelf:
+		r, size := utf8.DecodeRuneInString(s)
+		return r, true, s[size:], nil
+	case c != '\\':
+		return rune(s[0]), false, s[1:], nil
+	}
+
+	// hard case: c is backslash
+	if len(s) <= 1 {
+		err = ErrSyntax
+		return
+	}
+	c := s[1]
+	s = s[2:]
+
+	switch c {
+	case 'a':
+		value = '\a'
+	case 'b':
+		value = '\b'
+	case 'f':
+		value = '\f'
+	case 'n':
+		value = '\n'
+	case 'r':
+		value = '\r'
+	case 't':
+		value = '\t'
+	case 'v':
+		value = '\v'
+	case 'x', 'u', 'U':
+		n := 0
+		switch c {
+		case 'x':
+			n = 2
+		case 'u':
+			n = 4
+		case 'U':
+			n = 8
+		}
+		var v rune
+		if len(s) < n {
+			err = ErrSyntax
+			return
+		}
+		for j := 0; j < n; j++ {
+			x, ok := unhex(s[j])
+			if !ok {
+				err = ErrSyntax
+				return
+			}
+			v = v<<4 | x
+		}
+		s = s[n:]
+		if c == 'x' {
+			// single-byte string, possibly not UTF-8
+			value = v
+			break
+		}
+		if !utf8.ValidRune(v) {
+			err = ErrSyntax
+			return
+		}
+		value = v
+		multibyte = true
+	case '0', '1', '2', '3', '4', '5', '6', '7':
+		v := rune(c) - '0'
+		if len(s) < 2 {
+			err = ErrSyntax
+			return
+		}
+		for j := 0; j < 2; j++ { // one digit already; two more
+			x := rune(s[j]) - '0'
+			if x < 0 || x > 7 {
+				err = ErrSyntax
+				return
+			}
+			v = (v << 3) | x
+		}
+		s = s[2:]
+		if v > 255 {
+			err = ErrSyntax
+			return
+		}
+		value = v
+	case '\\':
+		value = '\\'
+	case '\'', '"':
+		if c != quote {
+			err = ErrSyntax
+			return
+		}
+		value = rune(c)
+	default:
+		err = ErrSyntax
+		return
+	}
+	tail = s
+	return
+}
+
+// QuotedPrefix returns the quoted string (as understood by Unquote) at the prefix of s.
+// If s does not start with a valid quoted string, QuotedPrefix returns an error.
+func QuotedPrefix(s string) (string, error) {
+	out, _, err := unquote(s, false)
+	return out, err
+}
+
+// Unquote interprets s as a single-quoted, double-quoted,
+// or backquoted Go string literal, returning the string value
+// that s quotes.  (If s is single-quoted, it would be a Go
+// character literal; Unquote returns the corresponding
+// one-character string.)
+func Unquote(s string) (string, error) {
+	out, rem, err := unquote(s, true)
+	if len(rem) > 0 {
+		return "", ErrSyntax
+	}
+	return out, err
+}
+
+// unquote parses a quoted string at the start of the input,
+// returning the parsed prefix, the remaining suffix, and any parse errors.
+// If unescape is true, the parsed prefix is unescaped,
+// otherwise the input prefix is provided verbatim.
+func unquote(in string, unescape bool) (out, rem string, err error) {
+	// Determine the quote form and optimistically find the terminating quote.
+	if len(in) < 2 {
+		return "", in, ErrSyntax
+	}
+	quote := in[0]
+	end := index(in[1:], quote)
+	if end < 0 {
+		return "", in, ErrSyntax
+	}
+	end += 2 // position after terminating quote; may be wrong if escape sequences are present
+
+	switch quote {
+	case '`':
+		switch {
+		case !unescape:
+			out = in[:end] // include quotes
+		case !contains(in[:end], '\r'):
+			out = in[len("`") : end-len("`")] // exclude quotes
+		default:
+			// Carriage return characters ('\r') inside raw string literals
+			// are discarded from the raw string value.
+			buf := make([]byte, 0, end-len("`")-len("\r")-len("`"))
+			for i := len("`"); i < end-len("`"); i++ {
+				if in[i] != '\r' {
+					buf = append(buf, in[i])
+				}
+			}
+			out = string(buf)
+		}
+		// NOTE: Prior implementations did not verify that raw strings consist
+		// of valid UTF-8 characters and we continue to not verify it as such.
+		// The Go specification does not explicitly require valid UTF-8,
+		// but only mention that it is implicitly valid for Go source code
+		// (which must be valid UTF-8).
+		return out, in[end:], nil
+	case '"', '\'':
+		// Handle quoted strings without any escape sequences.
+		if !contains(in[:end], '\\') && !contains(in[:end], '\n') {
+			var valid bool
+			switch quote {
+			case '"':
+				valid = utf8.ValidString(in[len(`"`) : end-len(`"`)])
+			case '\'':
+				r, n := utf8.DecodeRuneInString(in[len("'") : end-len("'")])
+				valid = len("'")+n+len("'") == end && (r != utf8.RuneError || n != 1)
+			}
+			if valid {
+				out = in[:end]
+				if unescape {
+					out = out[1 : end-1] // exclude quotes
+				}
+				return out, in[end:], nil
+			}
+		}
+
+		// Handle quoted strings with escape sequences.
+		var buf []byte
+		in0 := in
+		in = in[1:] // skip starting quote
+		if unescape {
+			buf = make([]byte, 0, 3*end/2) // try to avoid more allocations
+		}
+		for len(in) > 0 && in[0] != quote {
+			// Process the next character,
+			// rejecting any unescaped newline characters which are invalid.
+			r, multibyte, rem, err := UnquoteChar(in, quote)
+			if in[0] == '\n' || err != nil {
+				return "", in0, ErrSyntax
+			}
+			in = rem
+
+			// Append the character if unescaping the input.
+			if unescape {
+				if r < utf8.RuneSelf || !multibyte {
+					buf = append(buf, byte(r))
+				} else {
+					var arr [utf8.UTFMax]byte
+					n := utf8.EncodeRune(arr[:], r)
+					buf = append(buf, arr[:n]...)
+				}
+			}
+
+			// Single quoted strings must be a single character.
+			if quote == '\'' {
+				break
+			}
+		}
+
+		// Verify that the string ends with a terminating quote.
+		if !(len(in) > 0 && in[0] == quote) {
+			return "", in0, ErrSyntax
+		}
+		in = in[1:] // skip terminating quote
+
+		if unescape {
+			return string(buf), in, nil
+		}
+		return in0[:len(in0)-len(in)], in, nil
+	default:
+		return "", in, ErrSyntax
+	}
+}
+
+// bsearch16 returns the smallest i such that a[i] >= x.
+// If there is no such i, bsearch16 returns len(a).
+func bsearch16(a []uint16, x uint16) int {
+	i, j := 0, len(a)
+	for i < j {
+		h := i + (j-i)>>1
+		if a[h] < x {
+			i = h + 1
+		} else {
+			j = h
+		}
+	}
+	return i
+}
+
+// bsearch32 returns the smallest i such that a[i] >= x.
+// If there is no such i, bsearch32 returns len(a).
+func bsearch32(a []uint32, x uint32) int {
+	i, j := 0, len(a)
+	for i < j {
+		h := i + (j-i)>>1
+		if a[h] < x {
+			i = h + 1
+		} else {
+			j = h
+		}
+	}
+	return i
+}
+
+// TODO: IsPrint is a local implementation of unicode.IsPrint, verified by the tests
+// to give the same answer. It allows this package not to depend on unicode,
+// and therefore not pull in all the Unicode tables. If the linker were better
+// at tossing unused tables, we could get rid of this implementation.
+// That would be nice.
+
+// IsPrint reports whether the rune is defined as printable by Go, with
+// the same definition as unicode.IsPrint: letters, numbers, punctuation,
+// symbols and ASCII space.
+func IsPrint(r rune) bool {
+	// Fast check for Latin-1
+	if r <= 0xFF {
+		if 0x20 <= r && r <= 0x7E {
+			// All the ASCII is printable from space through DEL-1.
+			return true
+		}
+		if 0xA1 <= r && r <= 0xFF {
+			// Similarly for ¡ through ÿ...
+			return r != 0xAD // ...except for the bizarre soft hyphen.
+		}
+		return false
+	}
+
+	// Same algorithm, either on uint16 or uint32 value.
+	// First, find first i such that isPrint[i] >= x.
+	// This is the index of either the start or end of a pair that might span x.
+	// The start is even (isPrint[i&^1]) and the end is odd (isPrint[i|1]).
+	// If we find x in a range, make sure x is not in isNotPrint list.
+
+	if 0 <= r && r < 1<<16 {
+		rr, isPrint, isNotPrint := uint16(r), isPrint16, isNotPrint16
+		i := bsearch16(isPrint, rr)
+		if i >= len(isPrint) || rr < isPrint[i&^1] || isPrint[i|1] < rr {
+			return false
+		}
+		j := bsearch16(isNotPrint, rr)
+		return j >= len(isNotPrint) || isNotPrint[j] != rr
+	}
+
+	rr, isPrint, isNotPrint := uint32(r), isPrint32, isNotPrint32
+	i := bsearch32(isPrint, rr)
+	if i >= len(isPrint) || rr < isPrint[i&^1] || isPrint[i|1] < rr {
+		return false
+	}
+	if r >= 0x20000 {
+		return true
+	}
+	r -= 0x10000
+	j := bsearch16(isNotPrint, uint16(r))
+	return j >= len(isNotPrint) || isNotPrint[j] != uint16(r)
+}
+
+// IsGraphic reports whether the rune is defined as a Graphic by Unicode. Such
+// characters include letters, marks, numbers, punctuation, symbols, and
+// spaces, from categories L, M, N, P, S, and Zs.
+func IsGraphic(r rune) bool {
+	if IsPrint(r) {
+		return true
+	}
+	return isInGraphicList(r)
+}
+
+// isInGraphicList reports whether the rune is in the isGraphic list. This separation
+// from IsGraphic allows quoteWith to avoid two calls to IsPrint.
+// Should be called only if IsPrint fails.
+func isInGraphicList(r rune) bool {
+	// We know r must fit in 16 bits - see makeisprint.go.
+	if r > 0xFFFF {
+		return false
+	}
+	rr := uint16(r)
+	i := bsearch16(isGraphic, rr)
+	return i < len(isGraphic) && rr == isGraphic[i]
+}
diff --git a/contrib/go/_std_1.19/src/strings/builder.go b/contrib/go/_std_1.19/src/strings/builder.go
new file mode 100644
index 0000000000..3caddabd4e
--- /dev/null
+++ b/contrib/go/_std_1.19/src/strings/builder.go
@@ -0,0 +1,126 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package strings
+
+import (
+	"unicode/utf8"
+	"unsafe"
+)
+
+// A Builder is used to efficiently build a string using Write methods.
+// It minimizes memory copying. The zero value is ready to use.
+// Do not copy a non-zero Builder.
+type Builder struct {
+	addr *Builder // of receiver, to detect copies by value
+	buf  []byte
+}
+
+// noescape hides a pointer from escape analysis. It is the identity function
+// but escape analysis doesn't think the output depends on the input.
+// noescape is inlined and currently compiles down to zero instructions.
+// USE CAREFULLY!
+// This was copied from the runtime; see issues 23382 and 7921.
+//
+//go:nosplit
+//go:nocheckptr
+func noescape(p unsafe.Pointer) unsafe.Pointer {
+	x := uintptr(p)
+	return unsafe.Pointer(x ^ 0)
+}
+
+func (b *Builder) copyCheck() {
+	if b.addr == nil {
+		// This hack works around a failing of Go's escape analysis
+		// that was causing b to escape and be heap allocated.
+		// See issue 23382.
+		// TODO: once issue 7921 is fixed, this should be reverted to
+		// just "b.addr = b".
+		b.addr = (*Builder)(noescape(unsafe.Pointer(b)))
+	} else if b.addr != b {
+		panic("strings: illegal use of non-zero Builder copied by value")
+	}
+}
+
+// String returns the accumulated string.
+func (b *Builder) String() string {
+	return *(*string)(unsafe.Pointer(&b.buf))
+}
+
+// Len returns the number of accumulated bytes; b.Len() == len(b.String()).
+func (b *Builder) Len() int { return len(b.buf) }
+
+// Cap returns the capacity of the builder's underlying byte slice. It is the
+// total space allocated for the string being built and includes any bytes
+// already written.
+func (b *Builder) Cap() int { return cap(b.buf) }
+
+// Reset resets the Builder to be empty.
+func (b *Builder) Reset() {
+	b.addr = nil
+	b.buf = nil
+}
+
+// grow copies the buffer to a new, larger buffer so that there are at least n
+// bytes of capacity beyond len(b.buf).
+func (b *Builder) grow(n int) {
+	buf := make([]byte, len(b.buf), 2*cap(b.buf)+n)
+	copy(buf, b.buf)
+	b.buf = buf
+}
+
+// Grow grows b's capacity, if necessary, to guarantee space for
+// another n bytes. After Grow(n), at least n bytes can be written to b
+// without another allocation. If n is negative, Grow panics.
+func (b *Builder) Grow(n int) {
+	b.copyCheck()
+	if n < 0 {
+		panic("strings.Builder.Grow: negative count")
+	}
+	if cap(b.buf)-len(b.buf) < n {
+		b.grow(n)
+	}
+}
+
+// Write appends the contents of p to b's buffer.
+// Write always returns len(p), nil.
+func (b *Builder) Write(p []byte) (int, error) {
+	b.copyCheck()
+	b.buf = append(b.buf, p...)
+	return len(p), nil
+}
+
+// WriteByte appends the byte c to b's buffer.
+// The returned error is always nil.
+func (b *Builder) WriteByte(c byte) error {
+	b.copyCheck()
+	b.buf = append(b.buf, c)
+	return nil
+}
+
+// WriteRune appends the UTF-8 encoding of Unicode code point r to b's buffer.
+// It returns the length of r and a nil error.
+func (b *Builder) WriteRune(r rune) (int, error) {
+	b.copyCheck()
+	// Compare as uint32 to correctly handle negative runes.
+	if uint32(r) < utf8.RuneSelf {
+		b.buf = append(b.buf, byte(r))
+		return 1, nil
+	}
+	l := len(b.buf)
+	if cap(b.buf)-l < utf8.UTFMax {
+		b.grow(utf8.UTFMax)
+	}
+	n := utf8.EncodeRune(b.buf[l:l+utf8.UTFMax], r)
+	b.buf = b.buf[:l+n]
+	return n, nil
+}
+
+// WriteString appends the contents of s to b's buffer.
+// It returns the length of s and a nil error.
+func (b *Builder) WriteString(s string) (int, error) {
+	b.copyCheck()
+	b.buf = append(b.buf, s...)
+	return len(s), nil
+}
diff --git a/contrib/go/_std_1.18/src/strings/clone.go b/contrib/go/_std_1.19/src/strings/clone.go
index edd1497d9e..edd1497d9e 100644
--- a/contrib/go/_std_1.18/src/strings/clone.go
+++ b/contrib/go/_std_1.19/src/strings/clone.go
diff --git a/contrib/go/_std_1.18/src/strings/compare.go b/contrib/go/_std_1.19/src/strings/compare.go
index 2bd4a243db..2bd4a243db 100644
--- a/contrib/go/_std_1.18/src/strings/compare.go
+++ b/contrib/go/_std_1.19/src/strings/compare.go
diff --git a/contrib/go/_std_1.18/src/strings/reader.go b/contrib/go/_std_1.19/src/strings/reader.go
index 6f069a62ca..6f069a62ca 100644
--- a/contrib/go/_std_1.18/src/strings/reader.go
+++ b/contrib/go/_std_1.19/src/strings/reader.go
diff --git a/contrib/go/_std_1.19/src/strings/replace.go b/contrib/go/_std_1.19/src/strings/replace.go
new file mode 100644
index 0000000000..73bc78a07e
--- /dev/null
+++ b/contrib/go/_std_1.19/src/strings/replace.go
@@ -0,0 +1,569 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package strings
+
+import (
+	"io"
+	"sync"
+)
+
+// Replacer replaces a list of strings with replacements.
+// It is safe for concurrent use by multiple goroutines.
+type Replacer struct {
+	once   sync.Once // guards buildOnce method
+	r      replacer
+	oldnew []string
+}
+
+// replacer is the interface that a replacement algorithm needs to implement.
+type replacer interface {
+	Replace(s string) string
+	WriteString(w io.Writer, s string) (n int, err error)
+}
+
+// NewReplacer returns a new Replacer from a list of old, new string
+// pairs. Replacements are performed in the order they appear in the
+// target string, without overlapping matches. The old string
+// comparisons are done in argument order.
+//
+// NewReplacer panics if given an odd number of arguments.
+func NewReplacer(oldnew ...string) *Replacer {
+	if len(oldnew)%2 == 1 {
+		panic("strings.NewReplacer: odd argument count")
+	}
+	return &Replacer{oldnew: append([]string(nil), oldnew...)}
+}
+
+func (r *Replacer) buildOnce() {
+	r.r = r.build()
+	r.oldnew = nil
+}
+
+func (b *Replacer) build() replacer {
+	oldnew := b.oldnew
+	if len(oldnew) == 2 && len(oldnew[0]) > 1 {
+		return makeSingleStringReplacer(oldnew[0], oldnew[1])
+	}
+
+	allNewBytes := true
+	for i := 0; i < len(oldnew); i += 2 {
+		if len(oldnew[i]) != 1 {
+			return makeGenericReplacer(oldnew)
+		}
+		if len(oldnew[i+1]) != 1 {
+			allNewBytes = false
+		}
+	}
+
+	if allNewBytes {
+		r := byteReplacer{}
+		for i := range r {
+			r[i] = byte(i)
+		}
+		// The first occurrence of old->new map takes precedence
+		// over the others with the same old string.
+		for i := len(oldnew) - 2; i >= 0; i -= 2 {
+			o := oldnew[i][0]
+			n := oldnew[i+1][0]
+			r[o] = n
+		}
+		return &r
+	}
+
+	r := byteStringReplacer{toReplace: make([]string, 0, len(oldnew)/2)}
+	// The first occurrence of old->new map takes precedence
+	// over the others with the same old string.
+	for i := len(oldnew) - 2; i >= 0; i -= 2 {
+		o := oldnew[i][0]
+		n := oldnew[i+1]
+		// To avoid counting repetitions multiple times.
+		if r.replacements[o] == nil {
+			// We need to use string([]byte{o}) instead of string(o),
+			// to avoid utf8 encoding of o.
+			// E. g. byte(150) produces string of length 2.
+			r.toReplace = append(r.toReplace, string([]byte{o}))
+		}
+		r.replacements[o] = []byte(n)
+
+	}
+	return &r
+}
+
+// Replace returns a copy of s with all replacements performed.
+func (r *Replacer) Replace(s string) string {
+	r.once.Do(r.buildOnce)
+	return r.r.Replace(s)
+}
+
+// WriteString writes s to w with all replacements performed.
+func (r *Replacer) WriteString(w io.Writer, s string) (n int, err error) {
+	r.once.Do(r.buildOnce)
+	return r.r.WriteString(w, s)
+}
+
+// trieNode is a node in a lookup trie for prioritized key/value pairs. Keys
+// and values may be empty. For example, the trie containing keys "ax", "ay",
+// "bcbc", "x" and "xy" could have eight nodes:
+//
+//	n0  -
+//	n1  a-
+//	n2  .x+
+//	n3  .y+
+//	n4  b-
+//	n5  .cbc+
+//	n6  x+
+//	n7  .y+
+//
+// n0 is the root node, and its children are n1, n4 and n6; n1's children are
+// n2 and n3; n4's child is n5; n6's child is n7. Nodes n0, n1 and n4 (marked
+// with a trailing "-") are partial keys, and nodes n2, n3, n5, n6 and n7
+// (marked with a trailing "+") are complete keys.
+type trieNode struct {
+	// value is the value of the trie node's key/value pair. It is empty if
+	// this node is not a complete key.
+	value string
+	// priority is the priority (higher is more important) of the trie node's
+	// key/value pair; keys are not necessarily matched shortest- or longest-
+	// first. Priority is positive if this node is a complete key, and zero
+	// otherwise. In the example above, positive/zero priorities are marked
+	// with a trailing "+" or "-".
+	priority int
+
+	// A trie node may have zero, one or more child nodes:
+	//  * if the remaining fields are zero, there are no children.
+	//  * if prefix and next are non-zero, there is one child in next.
+	//  * if table is non-zero, it defines all the children.
+	//
+	// Prefixes are preferred over tables when there is one child, but the
+	// root node always uses a table for lookup efficiency.
+
+	// prefix is the difference in keys between this trie node and the next.
+	// In the example above, node n4 has prefix "cbc" and n4's next node is n5.
+	// Node n5 has no children and so has zero prefix, next and table fields.
+	prefix string
+	next   *trieNode
+
+	// table is a lookup table indexed by the next byte in the key, after
+	// remapping that byte through genericReplacer.mapping to create a dense
+	// index. In the example above, the keys only use 'a', 'b', 'c', 'x' and
+	// 'y', which remap to 0, 1, 2, 3 and 4. All other bytes remap to 5, and
+	// genericReplacer.tableSize will be 5. Node n0's table will be
+	// []*trieNode{ 0:n1, 1:n4, 3:n6 }, where the 0, 1 and 3 are the remapped
+	// 'a', 'b' and 'x'.
+	table []*trieNode
+}
+
+func (t *trieNode) add(key, val string, priority int, r *genericReplacer) {
+	if key == "" {
+		if t.priority == 0 {
+			t.value = val
+			t.priority = priority
+		}
+		return
+	}
+
+	if t.prefix != "" {
+		// Need to split the prefix among multiple nodes.
+		var n int // length of the longest common prefix
+		for ; n < len(t.prefix) && n < len(key); n++ {
+			if t.prefix[n] != key[n] {
+				break
+			}
+		}
+		if n == len(t.prefix) {
+			t.next.add(key[n:], val, priority, r)
+		} else if n == 0 {
+			// First byte differs, start a new lookup table here. Looking up
+			// what is currently t.prefix[0] will lead to prefixNode, and
+			// looking up key[0] will lead to keyNode.
+			var prefixNode *trieNode
+			if len(t.prefix) == 1 {
+				prefixNode = t.next
+			} else {
+				prefixNode = &trieNode{
+					prefix: t.prefix[1:],
+					next:   t.next,
+				}
+			}
+			keyNode := new(trieNode)
+			t.table = make([]*trieNode, r.tableSize)
+			t.table[r.mapping[t.prefix[0]]] = prefixNode
+			t.table[r.mapping[key[0]]] = keyNode
+			t.prefix = ""
+			t.next = nil
+			keyNode.add(key[1:], val, priority, r)
+		} else {
+			// Insert new node after the common section of the prefix.
+			next := &trieNode{
+				prefix: t.prefix[n:],
+				next:   t.next,
+			}
+			t.prefix = t.prefix[:n]
+			t.next = next
+			next.add(key[n:], val, priority, r)
+		}
+	} else if t.table != nil {
+		// Insert into existing table.
+		m := r.mapping[key[0]]
+		if t.table[m] == nil {
+			t.table[m] = new(trieNode)
+		}
+		t.table[m].add(key[1:], val, priority, r)
+	} else {
+		t.prefix = key
+		t.next = new(trieNode)
+		t.next.add("", val, priority, r)
+	}
+}
+
+func (r *genericReplacer) lookup(s string, ignoreRoot bool) (val string, keylen int, found bool) {
+	// Iterate down the trie to the end, and grab the value and keylen with
+	// the highest priority.
+	bestPriority := 0
+	node := &r.root
+	n := 0
+	for node != nil {
+		if node.priority > bestPriority && !(ignoreRoot && node == &r.root) {
+			bestPriority = node.priority
+			val = node.value
+			keylen = n
+			found = true
+		}
+
+		if s == "" {
+			break
+		}
+		if node.table != nil {
+			index := r.mapping[s[0]]
+			if int(index) == r.tableSize {
+				break
+			}
+			node = node.table[index]
+			s = s[1:]
+			n++
+		} else if node.prefix != "" && HasPrefix(s, node.prefix) {
+			n += len(node.prefix)
+			s = s[len(node.prefix):]
+			node = node.next
+		} else {
+			break
+		}
+	}
+	return
+}
+
+// genericReplacer is the fully generic algorithm.
+// It's used as a fallback when nothing faster can be used.
+type genericReplacer struct {
+	root trieNode
+	// tableSize is the size of a trie node's lookup table. It is the number
+	// of unique key bytes.
+	tableSize int
+	// mapping maps from key bytes to a dense index for trieNode.table.
+	mapping [256]byte
+}
+
+func makeGenericReplacer(oldnew []string) *genericReplacer {
+	r := new(genericReplacer)
+	// Find each byte used, then assign them each an index.
+	for i := 0; i < len(oldnew); i += 2 {
+		key := oldnew[i]
+		for j := 0; j < len(key); j++ {
+			r.mapping[key[j]] = 1
+		}
+	}
+
+	for _, b := range r.mapping {
+		r.tableSize += int(b)
+	}
+
+	var index byte
+	for i, b := range r.mapping {
+		if b == 0 {
+			r.mapping[i] = byte(r.tableSize)
+		} else {
+			r.mapping[i] = index
+			index++
+		}
+	}
+	// Ensure root node uses a lookup table (for performance).
+	r.root.table = make([]*trieNode, r.tableSize)
+
+	for i := 0; i < len(oldnew); i += 2 {
+		r.root.add(oldnew[i], oldnew[i+1], len(oldnew)-i, r)
+	}
+	return r
+}
+
+type appendSliceWriter []byte
+
+// Write writes to the buffer to satisfy io.Writer.
+func (w *appendSliceWriter) Write(p []byte) (int, error) {
+	*w = append(*w, p...)
+	return len(p), nil
+}
+
+// WriteString writes to the buffer without string->[]byte->string allocations.
+func (w *appendSliceWriter) WriteString(s string) (int, error) {
+	*w = append(*w, s...)
+	return len(s), nil
+}
+
+type stringWriter struct {
+	w io.Writer
+}
+
+func (w stringWriter) WriteString(s string) (int, error) {
+	return w.w.Write([]byte(s))
+}
+
+func getStringWriter(w io.Writer) io.StringWriter {
+	sw, ok := w.(io.StringWriter)
+	if !ok {
+		sw = stringWriter{w}
+	}
+	return sw
+}
+
+func (r *genericReplacer) Replace(s string) string {
+	buf := make(appendSliceWriter, 0, len(s))
+	r.WriteString(&buf, s)
+	return string(buf)
+}
+
+func (r *genericReplacer) WriteString(w io.Writer, s string) (n int, err error) {
+	sw := getStringWriter(w)
+	var last, wn int
+	var prevMatchEmpty bool
+	for i := 0; i <= len(s); {
+		// Fast path: s[i] is not a prefix of any pattern.
+		if i != len(s) && r.root.priority == 0 {
+			index := int(r.mapping[s[i]])
+			if index == r.tableSize || r.root.table[index] == nil {
+				i++
+				continue
+			}
+		}
+
+		// Ignore the empty match iff the previous loop found the empty match.
+		val, keylen, match := r.lookup(s[i:], prevMatchEmpty)
+		prevMatchEmpty = match && keylen == 0
+		if match {
+			wn, err = sw.WriteString(s[last:i])
+			n += wn
+			if err != nil {
+				return
+			}
+			wn, err = sw.WriteString(val)
+			n += wn
+			if err != nil {
+				return
+			}
+			i += keylen
+			last = i
+			continue
+		}
+		i++
+	}
+	if last != len(s) {
+		wn, err = sw.WriteString(s[last:])
+		n += wn
+	}
+	return
+}
+
+// singleStringReplacer is the implementation that's used when there is only
+// one string to replace (and that string has more than one byte).
+type singleStringReplacer struct {
+	finder *stringFinder
+	// value is the new string that replaces that pattern when it's found.
+	value string
+}
+
+func makeSingleStringReplacer(pattern string, value string) *singleStringReplacer {
+	return &singleStringReplacer{finder: makeStringFinder(pattern), value: value}
+}
+
+func (r *singleStringReplacer) Replace(s string) string {
+	var buf Builder
+	i, matched := 0, false
+	for {
+		match := r.finder.next(s[i:])
+		if match == -1 {
+			break
+		}
+		matched = true
+		buf.Grow(match + len(r.value))
+		buf.WriteString(s[i : i+match])
+		buf.WriteString(r.value)
+		i += match + len(r.finder.pattern)
+	}
+	if !matched {
+		return s
+	}
+	buf.WriteString(s[i:])
+	return buf.String()
+}
+
+func (r *singleStringReplacer) WriteString(w io.Writer, s string) (n int, err error) {
+	sw := getStringWriter(w)
+	var i, wn int
+	for {
+		match := r.finder.next(s[i:])
+		if match == -1 {
+			break
+		}
+		wn, err = sw.WriteString(s[i : i+match])
+		n += wn
+		if err != nil {
+			return
+		}
+		wn, err = sw.WriteString(r.value)
+		n += wn
+		if err != nil {
+			return
+		}
+		i += match + len(r.finder.pattern)
+	}
+	wn, err = sw.WriteString(s[i:])
+	n += wn
+	return
+}
+
+// byteReplacer is the implementation that's used when all the "old"
+// and "new" values are single ASCII bytes.
+// The array contains replacement bytes indexed by old byte.
+type byteReplacer [256]byte
+
+func (r *byteReplacer) Replace(s string) string {
+	var buf []byte // lazily allocated
+	for i := 0; i < len(s); i++ {
+		b := s[i]
+		if r[b] != b {
+			if buf == nil {
+				buf = []byte(s)
+			}
+			buf[i] = r[b]
+		}
+	}
+	if buf == nil {
+		return s
+	}
+	return string(buf)
+}
+
+func (r *byteReplacer) WriteString(w io.Writer, s string) (n int, err error) {
+	// TODO(bradfitz): use io.WriteString with slices of s, avoiding allocation.
+	bufsize := 32 << 10
+	if len(s) < bufsize {
+		bufsize = len(s)
+	}
+	buf := make([]byte, bufsize)
+
+	for len(s) > 0 {
+		ncopy := copy(buf, s)
+		s = s[ncopy:]
+		for i, b := range buf[:ncopy] {
+			buf[i] = r[b]
+		}
+		wn, err := w.Write(buf[:ncopy])
+		n += wn
+		if err != nil {
+			return n, err
+		}
+	}
+	return n, nil
+}
+
+// byteStringReplacer is the implementation that's used when all the
+// "old" values are single ASCII bytes but the "new" values vary in size.
+type byteStringReplacer struct {
+	// replacements contains replacement byte slices indexed by old byte.
+	// A nil []byte means that the old byte should not be replaced.
+	replacements [256][]byte
+	// toReplace keeps a list of bytes to replace. Depending on length of toReplace
+	// and length of target string it may be faster to use Count, or a plain loop.
+	// We store single byte as a string, because Count takes a string.
+	toReplace []string
+}
+
+// countCutOff controls the ratio of a string length to a number of replacements
+// at which (*byteStringReplacer).Replace switches algorithms.
+// For strings with higher ration of length to replacements than that value,
+// we call Count, for each replacement from toReplace.
+// For strings, with a lower ratio we use simple loop, because of Count overhead.
+// countCutOff is an empirically determined overhead multiplier.
+// TODO(tocarip) revisit once we have register-based abi/mid-stack inlining.
+const countCutOff = 8
+
+func (r *byteStringReplacer) Replace(s string) string {
+	newSize := len(s)
+	anyChanges := false
+	// Is it faster to use Count?
+	if len(r.toReplace)*countCutOff <= len(s) {
+		for _, x := range r.toReplace {
+			if c := Count(s, x); c != 0 {
+				// The -1 is because we are replacing 1 byte with len(replacements[b]) bytes.
+				newSize += c * (len(r.replacements[x[0]]) - 1)
+				anyChanges = true
+			}
+
+		}
+	} else {
+		for i := 0; i < len(s); i++ {
+			b := s[i]
+			if r.replacements[b] != nil {
+				// See above for explanation of -1
+				newSize += len(r.replacements[b]) - 1
+				anyChanges = true
+			}
+		}
+	}
+	if !anyChanges {
+		return s
+	}
+	buf := make([]byte, newSize)
+	j := 0
+	for i := 0; i < len(s); i++ {
+		b := s[i]
+		if r.replacements[b] != nil {
+			j += copy(buf[j:], r.replacements[b])
+		} else {
+			buf[j] = b
+			j++
+		}
+	}
+	return string(buf)
+}
+
+func (r *byteStringReplacer) WriteString(w io.Writer, s string) (n int, err error) {
+	sw := getStringWriter(w)
+	last := 0
+	for i := 0; i < len(s); i++ {
+		b := s[i]
+		if r.replacements[b] == nil {
+			continue
+		}
+		if last != i {
+			nw, err := sw.WriteString(s[last:i])
+			n += nw
+			if err != nil {
+				return n, err
+			}
+		}
+		last = i + 1
+		nw, err := w.Write(r.replacements[b])
+		n += nw
+		if err != nil {
+			return n, err
+		}
+	}
+	if last != len(s) {
+		var nw int
+		nw, err = sw.WriteString(s[last:])
+		n += nw
+	}
+	return
+}
diff --git a/contrib/go/_std_1.18/src/strings/search.go b/contrib/go/_std_1.19/src/strings/search.go
index e5bffbbfe8..e5bffbbfe8 100644
--- a/contrib/go/_std_1.18/src/strings/search.go
+++ b/contrib/go/_std_1.19/src/strings/search.go
diff --git a/contrib/go/_std_1.19/src/strings/strings.go b/contrib/go/_std_1.19/src/strings/strings.go
new file mode 100644
index 0000000000..1dc4238522
--- /dev/null
+++ b/contrib/go/_std_1.19/src/strings/strings.go
@@ -0,0 +1,1192 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package strings implements simple functions to manipulate UTF-8 encoded strings.
+//
+// For information about UTF-8 strings in Go, see https://blog.golang.org/strings.
+package strings
+
+import (
+	"internal/bytealg"
+	"unicode"
+	"unicode/utf8"
+)
+
+// explode splits s into a slice of UTF-8 strings,
+// one string per Unicode character up to a maximum of n (n < 0 means no limit).
+// Invalid UTF-8 sequences become correct encodings of U+FFFD.
+func explode(s string, n int) []string {
+	l := utf8.RuneCountInString(s)
+	if n < 0 || n > l {
+		n = l
+	}
+	a := make([]string, n)
+	for i := 0; i < n-1; i++ {
+		ch, size := utf8.DecodeRuneInString(s)
+		a[i] = s[:size]
+		s = s[size:]
+		if ch == utf8.RuneError {
+			a[i] = string(utf8.RuneError)
+		}
+	}
+	if n > 0 {
+		a[n-1] = s
+	}
+	return a
+}
+
+// Count counts the number of non-overlapping instances of substr in s.
+// If substr is an empty string, Count returns 1 + the number of Unicode code points in s.
+func Count(s, substr string) int {
+	// special case
+	if len(substr) == 0 {
+		return utf8.RuneCountInString(s) + 1
+	}
+	if len(substr) == 1 {
+		return bytealg.CountString(s, substr[0])
+	}
+	n := 0
+	for {
+		i := Index(s, substr)
+		if i == -1 {
+			return n
+		}
+		n++
+		s = s[i+len(substr):]
+	}
+}
+
+// Contains reports whether substr is within s.
+func Contains(s, substr string) bool {
+	return Index(s, substr) >= 0
+}
+
+// ContainsAny reports whether any Unicode code points in chars are within s.
+func ContainsAny(s, chars string) bool {
+	return IndexAny(s, chars) >= 0
+}
+
+// ContainsRune reports whether the Unicode code point r is within s.
+func ContainsRune(s string, r rune) bool {
+	return IndexRune(s, r) >= 0
+}
+
+// LastIndex returns the index of the last instance of substr in s, or -1 if substr is not present in s.
+func LastIndex(s, substr string) int {
+	n := len(substr)
+	switch {
+	case n == 0:
+		return len(s)
+	case n == 1:
+		return LastIndexByte(s, substr[0])
+	case n == len(s):
+		if substr == s {
+			return 0
+		}
+		return -1
+	case n > len(s):
+		return -1
+	}
+	// Rabin-Karp search from the end of the string
+	hashss, pow := bytealg.HashStrRev(substr)
+	last := len(s) - n
+	var h uint32
+	for i := len(s) - 1; i >= last; i-- {
+		h = h*bytealg.PrimeRK + uint32(s[i])
+	}
+	if h == hashss && s[last:] == substr {
+		return last
+	}
+	for i := last - 1; i >= 0; i-- {
+		h *= bytealg.PrimeRK
+		h += uint32(s[i])
+		h -= pow * uint32(s[i+n])
+		if h == hashss && s[i:i+n] == substr {
+			return i
+		}
+	}
+	return -1
+}
+
+// IndexByte returns the index of the first instance of c in s, or -1 if c is not present in s.
+func IndexByte(s string, c byte) int {
+	return bytealg.IndexByteString(s, c)
+}
+
+// IndexRune returns the index of the first instance of the Unicode code point
+// r, or -1 if rune is not present in s.
+// If r is utf8.RuneError, it returns the first instance of any
+// invalid UTF-8 byte sequence.
+func IndexRune(s string, r rune) int {
+	switch {
+	case 0 <= r && r < utf8.RuneSelf:
+		return IndexByte(s, byte(r))
+	case r == utf8.RuneError:
+		for i, r := range s {
+			if r == utf8.RuneError {
+				return i
+			}
+		}
+		return -1
+	case !utf8.ValidRune(r):
+		return -1
+	default:
+		return Index(s, string(r))
+	}
+}
+
+// IndexAny returns the index of the first instance of any Unicode code point
+// from chars in s, or -1 if no Unicode code point from chars is present in s.
+func IndexAny(s, chars string) int {
+	if chars == "" {
+		// Avoid scanning all of s.
+		return -1
+	}
+	if len(chars) == 1 {
+		// Avoid scanning all of s.
+		r := rune(chars[0])
+		if r >= utf8.RuneSelf {
+			r = utf8.RuneError
+		}
+		return IndexRune(s, r)
+	}
+	if len(s) > 8 {
+		if as, isASCII := makeASCIISet(chars); isASCII {
+			for i := 0; i < len(s); i++ {
+				if as.contains(s[i]) {
+					return i
+				}
+			}
+			return -1
+		}
+	}
+	for i, c := range s {
+		if IndexRune(chars, c) >= 0 {
+			return i
+		}
+	}
+	return -1
+}
+
+// LastIndexAny returns the index of the last instance of any Unicode code
+// point from chars in s, or -1 if no Unicode code point from chars is
+// present in s.
+func LastIndexAny(s, chars string) int {
+	if chars == "" {
+		// Avoid scanning all of s.
+		return -1
+	}
+	if len(s) == 1 {
+		rc := rune(s[0])
+		if rc >= utf8.RuneSelf {
+			rc = utf8.RuneError
+		}
+		if IndexRune(chars, rc) >= 0 {
+			return 0
+		}
+		return -1
+	}
+	if len(s) > 8 {
+		if as, isASCII := makeASCIISet(chars); isASCII {
+			for i := len(s) - 1; i >= 0; i-- {
+				if as.contains(s[i]) {
+					return i
+				}
+			}
+			return -1
+		}
+	}
+	if len(chars) == 1 {
+		rc := rune(chars[0])
+		if rc >= utf8.RuneSelf {
+			rc = utf8.RuneError
+		}
+		for i := len(s); i > 0; {
+			r, size := utf8.DecodeLastRuneInString(s[:i])
+			i -= size
+			if rc == r {
+				return i
+			}
+		}
+		return -1
+	}
+	for i := len(s); i > 0; {
+		r, size := utf8.DecodeLastRuneInString(s[:i])
+		i -= size
+		if IndexRune(chars, r) >= 0 {
+			return i
+		}
+	}
+	return -1
+}
+
+// LastIndexByte returns the index of the last instance of c in s, or -1 if c is not present in s.
+func LastIndexByte(s string, c byte) int {
+	for i := len(s) - 1; i >= 0; i-- {
+		if s[i] == c {
+			return i
+		}
+	}
+	return -1
+}
+
+// Generic split: splits after each instance of sep,
+// including sepSave bytes of sep in the subarrays.
+func genSplit(s, sep string, sepSave, n int) []string {
+	if n == 0 {
+		return nil
+	}
+	if sep == "" {
+		return explode(s, n)
+	}
+	if n < 0 {
+		n = Count(s, sep) + 1
+	}
+
+	if n > len(s)+1 {
+		n = len(s) + 1
+	}
+	a := make([]string, n)
+	n--
+	i := 0
+	for i < n {
+		m := Index(s, sep)
+		if m < 0 {
+			break
+		}
+		a[i] = s[:m+sepSave]
+		s = s[m+len(sep):]
+		i++
+	}
+	a[i] = s
+	return a[:i+1]
+}
+
+// SplitN slices s into substrings separated by sep and returns a slice of
+// the substrings between those separators.
+//
+// The count determines the number of substrings to return:
+//
+//	n > 0: at most n substrings; the last substring will be the unsplit remainder.
+//	n == 0: the result is nil (zero substrings)
+//	n < 0: all substrings
+//
+// Edge cases for s and sep (for example, empty strings) are handled
+// as described in the documentation for Split.
+//
+// To split around the first instance of a separator, see Cut.
+func SplitN(s, sep string, n int) []string { return genSplit(s, sep, 0, n) }
+
+// SplitAfterN slices s into substrings after each instance of sep and
+// returns a slice of those substrings.
+//
+// The count determines the number of substrings to return:
+//
+//	n > 0: at most n substrings; the last substring will be the unsplit remainder.
+//	n == 0: the result is nil (zero substrings)
+//	n < 0: all substrings
+//
+// Edge cases for s and sep (for example, empty strings) are handled
+// as described in the documentation for SplitAfter.
+func SplitAfterN(s, sep string, n int) []string {
+	return genSplit(s, sep, len(sep), n)
+}
+
+// Split slices s into all substrings separated by sep and returns a slice of
+// the substrings between those separators.
+//
+// If s does not contain sep and sep is not empty, Split returns a
+// slice of length 1 whose only element is s.
+//
+// If sep is empty, Split splits after each UTF-8 sequence. If both s
+// and sep are empty, Split returns an empty slice.
+//
+// It is equivalent to SplitN with a count of -1.
+//
+// To split around the first instance of a separator, see Cut.
+func Split(s, sep string) []string { return genSplit(s, sep, 0, -1) }
+
+// SplitAfter slices s into all substrings after each instance of sep and
+// returns a slice of those substrings.
+//
+// If s does not contain sep and sep is not empty, SplitAfter returns
+// a slice of length 1 whose only element is s.
+//
+// If sep is empty, SplitAfter splits after each UTF-8 sequence. If
+// both s and sep are empty, SplitAfter returns an empty slice.
+//
+// It is equivalent to SplitAfterN with a count of -1.
+func SplitAfter(s, sep string) []string {
+	return genSplit(s, sep, len(sep), -1)
+}
+
+var asciiSpace = [256]uint8{'\t': 1, '\n': 1, '\v': 1, '\f': 1, '\r': 1, ' ': 1}
+
+// Fields splits the string s around each instance of one or more consecutive white space
+// characters, as defined by unicode.IsSpace, returning a slice of substrings of s or an
+// empty slice if s contains only white space.
+func Fields(s string) []string {
+	// First count the fields.
+	// This is an exact count if s is ASCII, otherwise it is an approximation.
+	n := 0
+	wasSpace := 1
+	// setBits is used to track which bits are set in the bytes of s.
+	setBits := uint8(0)
+	for i := 0; i < len(s); i++ {
+		r := s[i]
+		setBits |= r
+		isSpace := int(asciiSpace[r])
+		n += wasSpace & ^isSpace
+		wasSpace = isSpace
+	}
+
+	if setBits >= utf8.RuneSelf {
+		// Some runes in the input string are not ASCII.
+		return FieldsFunc(s, unicode.IsSpace)
+	}
+	// ASCII fast path
+	a := make([]string, n)
+	na := 0
+	fieldStart := 0
+	i := 0
+	// Skip spaces in the front of the input.
+	for i < len(s) && asciiSpace[s[i]] != 0 {
+		i++
+	}
+	fieldStart = i
+	for i < len(s) {
+		if asciiSpace[s[i]] == 0 {
+			i++
+			continue
+		}
+		a[na] = s[fieldStart:i]
+		na++
+		i++
+		// Skip spaces in between fields.
+		for i < len(s) && asciiSpace[s[i]] != 0 {
+			i++
+		}
+		fieldStart = i
+	}
+	if fieldStart < len(s) { // Last field might end at EOF.
+		a[na] = s[fieldStart:]
+	}
+	return a
+}
+
+// FieldsFunc splits the string s at each run of Unicode code points c satisfying f(c)
+// and returns an array of slices of s. If all code points in s satisfy f(c) or the
+// string is empty, an empty slice is returned.
+//
+// FieldsFunc makes no guarantees about the order in which it calls f(c)
+// and assumes that f always returns the same value for a given c.
+func FieldsFunc(s string, f func(rune) bool) []string {
+	// A span is used to record a slice of s of the form s[start:end].
+	// The start index is inclusive and the end index is exclusive.
+	type span struct {
+		start int
+		end   int
+	}
+	spans := make([]span, 0, 32)
+
+	// Find the field start and end indices.
+	// Doing this in a separate pass (rather than slicing the string s
+	// and collecting the result substrings right away) is significantly
+	// more efficient, possibly due to cache effects.
+	start := -1 // valid span start if >= 0
+	for end, rune := range s {
+		if f(rune) {
+			if start >= 0 {
+				spans = append(spans, span{start, end})
+				// Set start to a negative value.
+				// Note: using -1 here consistently and reproducibly
+				// slows down this code by a several percent on amd64.
+				start = ^start
+			}
+		} else {
+			if start < 0 {
+				start = end
+			}
+		}
+	}
+
+	// Last field might end at EOF.
+	if start >= 0 {
+		spans = append(spans, span{start, len(s)})
+	}
+
+	// Create strings from recorded field indices.
+	a := make([]string, len(spans))
+	for i, span := range spans {
+		a[i] = s[span.start:span.end]
+	}
+
+	return a
+}
+
+// Join concatenates the elements of its first argument to create a single string. The separator
+// string sep is placed between elements in the resulting string.
+func Join(elems []string, sep string) string {
+	switch len(elems) {
+	case 0:
+		return ""
+	case 1:
+		return elems[0]
+	}
+	n := len(sep) * (len(elems) - 1)
+	for i := 0; i < len(elems); i++ {
+		n += len(elems[i])
+	}
+
+	var b Builder
+	b.Grow(n)
+	b.WriteString(elems[0])
+	for _, s := range elems[1:] {
+		b.WriteString(sep)
+		b.WriteString(s)
+	}
+	return b.String()
+}
+
+// HasPrefix tests whether the string s begins with prefix.
+func HasPrefix(s, prefix string) bool {
+	return len(s) >= len(prefix) && s[0:len(prefix)] == prefix
+}
+
+// HasSuffix tests whether the string s ends with suffix.
+func HasSuffix(s, suffix string) bool {
+	return len(s) >= len(suffix) && s[len(s)-len(suffix):] == suffix
+}
+
+// Map returns a copy of the string s with all its characters modified
+// according to the mapping function. If mapping returns a negative value, the character is
+// dropped from the string with no replacement.
+func Map(mapping func(rune) rune, s string) string {
+	// In the worst case, the string can grow when mapped, making
+	// things unpleasant. But it's so rare we barge in assuming it's
+	// fine. It could also shrink but that falls out naturally.
+
+	// The output buffer b is initialized on demand, the first
+	// time a character differs.
+	var b Builder
+
+	for i, c := range s {
+		r := mapping(c)
+		if r == c && c != utf8.RuneError {
+			continue
+		}
+
+		var width int
+		if c == utf8.RuneError {
+			c, width = utf8.DecodeRuneInString(s[i:])
+			if width != 1 && r == c {
+				continue
+			}
+		} else {
+			width = utf8.RuneLen(c)
+		}
+
+		b.Grow(len(s) + utf8.UTFMax)
+		b.WriteString(s[:i])
+		if r >= 0 {
+			b.WriteRune(r)
+		}
+
+		s = s[i+width:]
+		break
+	}
+
+	// Fast path for unchanged input
+	if b.Cap() == 0 { // didn't call b.Grow above
+		return s
+	}
+
+	for _, c := range s {
+		r := mapping(c)
+
+		if r >= 0 {
+			// common case
+			// Due to inlining, it is more performant to determine if WriteByte should be
+			// invoked rather than always call WriteRune
+			if r < utf8.RuneSelf {
+				b.WriteByte(byte(r))
+			} else {
+				// r is not a ASCII rune.
+				b.WriteRune(r)
+			}
+		}
+	}
+
+	return b.String()
+}
+
+// Repeat returns a new string consisting of count copies of the string s.
+//
+// It panics if count is negative or if
+// the result of (len(s) * count) overflows.
+func Repeat(s string, count int) string {
+	if count == 0 {
+		return ""
+	}
+
+	// Since we cannot return an error on overflow,
+	// we should panic if the repeat will generate
+	// an overflow.
+	// See Issue golang.org/issue/16237
+	if count < 0 {
+		panic("strings: negative Repeat count")
+	} else if len(s)*count/count != len(s) {
+		panic("strings: Repeat count causes overflow")
+	}
+
+	n := len(s) * count
+	var b Builder
+	b.Grow(n)
+	b.WriteString(s)
+	for b.Len() < n {
+		if b.Len() <= n/2 {
+			b.WriteString(b.String())
+		} else {
+			b.WriteString(b.String()[:n-b.Len()])
+			break
+		}
+	}
+	return b.String()
+}
+
+// ToUpper returns s with all Unicode letters mapped to their upper case.
+func ToUpper(s string) string {
+	isASCII, hasLower := true, false
+	for i := 0; i < len(s); i++ {
+		c := s[i]
+		if c >= utf8.RuneSelf {
+			isASCII = false
+			break
+		}
+		hasLower = hasLower || ('a' <= c && c <= 'z')
+	}
+
+	if isASCII { // optimize for ASCII-only strings.
+		if !hasLower {
+			return s
+		}
+		var b Builder
+		b.Grow(len(s))
+		for i := 0; i < len(s); i++ {
+			c := s[i]
+			if 'a' <= c && c <= 'z' {
+				c -= 'a' - 'A'
+			}
+			b.WriteByte(c)
+		}
+		return b.String()
+	}
+	return Map(unicode.ToUpper, s)
+}
+
+// ToLower returns s with all Unicode letters mapped to their lower case.
+func ToLower(s string) string {
+	isASCII, hasUpper := true, false
+	for i := 0; i < len(s); i++ {
+		c := s[i]
+		if c >= utf8.RuneSelf {
+			isASCII = false
+			break
+		}
+		hasUpper = hasUpper || ('A' <= c && c <= 'Z')
+	}
+
+	if isASCII { // optimize for ASCII-only strings.
+		if !hasUpper {
+			return s
+		}
+		var b Builder
+		b.Grow(len(s))
+		for i := 0; i < len(s); i++ {
+			c := s[i]
+			if 'A' <= c && c <= 'Z' {
+				c += 'a' - 'A'
+			}
+			b.WriteByte(c)
+		}
+		return b.String()
+	}
+	return Map(unicode.ToLower, s)
+}
+
+// ToTitle returns a copy of the string s with all Unicode letters mapped to
+// their Unicode title case.
+func ToTitle(s string) string { return Map(unicode.ToTitle, s) }
+
+// ToUpperSpecial returns a copy of the string s with all Unicode letters mapped to their
+// upper case using the case mapping specified by c.
+func ToUpperSpecial(c unicode.SpecialCase, s string) string {
+	return Map(c.ToUpper, s)
+}
+
+// ToLowerSpecial returns a copy of the string s with all Unicode letters mapped to their
+// lower case using the case mapping specified by c.
+func ToLowerSpecial(c unicode.SpecialCase, s string) string {
+	return Map(c.ToLower, s)
+}
+
+// ToTitleSpecial returns a copy of the string s with all Unicode letters mapped to their
+// Unicode title case, giving priority to the special casing rules.
+func ToTitleSpecial(c unicode.SpecialCase, s string) string {
+	return Map(c.ToTitle, s)
+}
+
+// ToValidUTF8 returns a copy of the string s with each run of invalid UTF-8 byte sequences
+// replaced by the replacement string, which may be empty.
+func ToValidUTF8(s, replacement string) string {
+	var b Builder
+
+	for i, c := range s {
+		if c != utf8.RuneError {
+			continue
+		}
+
+		_, wid := utf8.DecodeRuneInString(s[i:])
+		if wid == 1 {
+			b.Grow(len(s) + len(replacement))
+			b.WriteString(s[:i])
+			s = s[i:]
+			break
+		}
+	}
+
+	// Fast path for unchanged input
+	if b.Cap() == 0 { // didn't call b.Grow above
+		return s
+	}
+
+	invalid := false // previous byte was from an invalid UTF-8 sequence
+	for i := 0; i < len(s); {
+		c := s[i]
+		if c < utf8.RuneSelf {
+			i++
+			invalid = false
+			b.WriteByte(c)
+			continue
+		}
+		_, wid := utf8.DecodeRuneInString(s[i:])
+		if wid == 1 {
+			i++
+			if !invalid {
+				invalid = true
+				b.WriteString(replacement)
+			}
+			continue
+		}
+		invalid = false
+		b.WriteString(s[i : i+wid])
+		i += wid
+	}
+
+	return b.String()
+}
+
+// isSeparator reports whether the rune could mark a word boundary.
+// TODO: update when package unicode captures more of the properties.
+func isSeparator(r rune) bool {
+	// ASCII alphanumerics and underscore are not separators
+	if r <= 0x7F {
+		switch {
+		case '0' <= r && r <= '9':
+			return false
+		case 'a' <= r && r <= 'z':
+			return false
+		case 'A' <= r && r <= 'Z':
+			return false
+		case r == '_':
+			return false
+		}
+		return true
+	}
+	// Letters and digits are not separators
+	if unicode.IsLetter(r) || unicode.IsDigit(r) {
+		return false
+	}
+	// Otherwise, all we can do for now is treat spaces as separators.
+	return unicode.IsSpace(r)
+}
+
+// Title returns a copy of the string s with all Unicode letters that begin words
+// mapped to their Unicode title case.
+//
+// Deprecated: The rule Title uses for word boundaries does not handle Unicode
+// punctuation properly. Use golang.org/x/text/cases instead.
+func Title(s string) string {
+	// Use a closure here to remember state.
+	// Hackish but effective. Depends on Map scanning in order and calling
+	// the closure once per rune.
+	prev := ' '
+	return Map(
+		func(r rune) rune {
+			if isSeparator(prev) {
+				prev = r
+				return unicode.ToTitle(r)
+			}
+			prev = r
+			return r
+		},
+		s)
+}
+
+// TrimLeftFunc returns a slice of the string s with all leading
+// Unicode code points c satisfying f(c) removed.
+func TrimLeftFunc(s string, f func(rune) bool) string {
+	i := indexFunc(s, f, false)
+	if i == -1 {
+		return ""
+	}
+	return s[i:]
+}
+
+// TrimRightFunc returns a slice of the string s with all trailing
+// Unicode code points c satisfying f(c) removed.
+func TrimRightFunc(s string, f func(rune) bool) string {
+	i := lastIndexFunc(s, f, false)
+	if i >= 0 && s[i] >= utf8.RuneSelf {
+		_, wid := utf8.DecodeRuneInString(s[i:])
+		i += wid
+	} else {
+		i++
+	}
+	return s[0:i]
+}
+
+// TrimFunc returns a slice of the string s with all leading
+// and trailing Unicode code points c satisfying f(c) removed.
+func TrimFunc(s string, f func(rune) bool) string {
+	return TrimRightFunc(TrimLeftFunc(s, f), f)
+}
+
+// IndexFunc returns the index into s of the first Unicode
+// code point satisfying f(c), or -1 if none do.
+func IndexFunc(s string, f func(rune) bool) int {
+	return indexFunc(s, f, true)
+}
+
+// LastIndexFunc returns the index into s of the last
+// Unicode code point satisfying f(c), or -1 if none do.
+func LastIndexFunc(s string, f func(rune) bool) int {
+	return lastIndexFunc(s, f, true)
+}
+
+// indexFunc is the same as IndexFunc except that if
+// truth==false, the sense of the predicate function is
+// inverted.
+func indexFunc(s string, f func(rune) bool, truth bool) int {
+	for i, r := range s {
+		if f(r) == truth {
+			return i
+		}
+	}
+	return -1
+}
+
+// lastIndexFunc is the same as LastIndexFunc except that if
+// truth==false, the sense of the predicate function is
+// inverted.
+func lastIndexFunc(s string, f func(rune) bool, truth bool) int {
+	for i := len(s); i > 0; {
+		r, size := utf8.DecodeLastRuneInString(s[0:i])
+		i -= size
+		if f(r) == truth {
+			return i
+		}
+	}
+	return -1
+}
+
+// asciiSet is a 32-byte value, where each bit represents the presence of a
+// given ASCII character in the set. The 128-bits of the lower 16 bytes,
+// starting with the least-significant bit of the lowest word to the
+// most-significant bit of the highest word, map to the full range of all
+// 128 ASCII characters. The 128-bits of the upper 16 bytes will be zeroed,
+// ensuring that any non-ASCII character will be reported as not in the set.
+// This allocates a total of 32 bytes even though the upper half
+// is unused to avoid bounds checks in asciiSet.contains.
+type asciiSet [8]uint32
+
+// makeASCIISet creates a set of ASCII characters and reports whether all
+// characters in chars are ASCII.
+func makeASCIISet(chars string) (as asciiSet, ok bool) {
+	for i := 0; i < len(chars); i++ {
+		c := chars[i]
+		if c >= utf8.RuneSelf {
+			return as, false
+		}
+		as[c/32] |= 1 << (c % 32)
+	}
+	return as, true
+}
+
+// contains reports whether c is inside the set.
+func (as *asciiSet) contains(c byte) bool {
+	return (as[c/32] & (1 << (c % 32))) != 0
+}
+
+// Trim returns a slice of the string s with all leading and
+// trailing Unicode code points contained in cutset removed.
+func Trim(s, cutset string) string {
+	if s == "" || cutset == "" {
+		return s
+	}
+	if len(cutset) == 1 && cutset[0] < utf8.RuneSelf {
+		return trimLeftByte(trimRightByte(s, cutset[0]), cutset[0])
+	}
+	if as, ok := makeASCIISet(cutset); ok {
+		return trimLeftASCII(trimRightASCII(s, &as), &as)
+	}
+	return trimLeftUnicode(trimRightUnicode(s, cutset), cutset)
+}
+
+// TrimLeft returns a slice of the string s with all leading
+// Unicode code points contained in cutset removed.
+//
+// To remove a prefix, use TrimPrefix instead.
+func TrimLeft(s, cutset string) string {
+	if s == "" || cutset == "" {
+		return s
+	}
+	if len(cutset) == 1 && cutset[0] < utf8.RuneSelf {
+		return trimLeftByte(s, cutset[0])
+	}
+	if as, ok := makeASCIISet(cutset); ok {
+		return trimLeftASCII(s, &as)
+	}
+	return trimLeftUnicode(s, cutset)
+}
+
+func trimLeftByte(s string, c byte) string {
+	for len(s) > 0 && s[0] == c {
+		s = s[1:]
+	}
+	return s
+}
+
+func trimLeftASCII(s string, as *asciiSet) string {
+	for len(s) > 0 {
+		if !as.contains(s[0]) {
+			break
+		}
+		s = s[1:]
+	}
+	return s
+}
+
+func trimLeftUnicode(s, cutset string) string {
+	for len(s) > 0 {
+		r, n := rune(s[0]), 1
+		if r >= utf8.RuneSelf {
+			r, n = utf8.DecodeRuneInString(s)
+		}
+		if !ContainsRune(cutset, r) {
+			break
+		}
+		s = s[n:]
+	}
+	return s
+}
+
+// TrimRight returns a slice of the string s, with all trailing
+// Unicode code points contained in cutset removed.
+//
+// To remove a suffix, use TrimSuffix instead.
+func TrimRight(s, cutset string) string {
+	if s == "" || cutset == "" {
+		return s
+	}
+	if len(cutset) == 1 && cutset[0] < utf8.RuneSelf {
+		return trimRightByte(s, cutset[0])
+	}
+	if as, ok := makeASCIISet(cutset); ok {
+		return trimRightASCII(s, &as)
+	}
+	return trimRightUnicode(s, cutset)
+}
+
+func trimRightByte(s string, c byte) string {
+	for len(s) > 0 && s[len(s)-1] == c {
+		s = s[:len(s)-1]
+	}
+	return s
+}
+
+func trimRightASCII(s string, as *asciiSet) string {
+	for len(s) > 0 {
+		if !as.contains(s[len(s)-1]) {
+			break
+		}
+		s = s[:len(s)-1]
+	}
+	return s
+}
+
+func trimRightUnicode(s, cutset string) string {
+	for len(s) > 0 {
+		r, n := rune(s[len(s)-1]), 1
+		if r >= utf8.RuneSelf {
+			r, n = utf8.DecodeLastRuneInString(s)
+		}
+		if !ContainsRune(cutset, r) {
+			break
+		}
+		s = s[:len(s)-n]
+	}
+	return s
+}
+
+// TrimSpace returns a slice of the string s, with all leading
+// and trailing white space removed, as defined by Unicode.
+func TrimSpace(s string) string {
+	// Fast path for ASCII: look for the first ASCII non-space byte
+	start := 0
+	for ; start < len(s); start++ {
+		c := s[start]
+		if c >= utf8.RuneSelf {
+			// If we run into a non-ASCII byte, fall back to the
+			// slower unicode-aware method on the remaining bytes
+			return TrimFunc(s[start:], unicode.IsSpace)
+		}
+		if asciiSpace[c] == 0 {
+			break
+		}
+	}
+
+	// Now look for the first ASCII non-space byte from the end
+	stop := len(s)
+	for ; stop > start; stop-- {
+		c := s[stop-1]
+		if c >= utf8.RuneSelf {
+			// start has been already trimmed above, should trim end only
+			return TrimRightFunc(s[start:stop], unicode.IsSpace)
+		}
+		if asciiSpace[c] == 0 {
+			break
+		}
+	}
+
+	// At this point s[start:stop] starts and ends with an ASCII
+	// non-space bytes, so we're done. Non-ASCII cases have already
+	// been handled above.
+	return s[start:stop]
+}
+
+// TrimPrefix returns s without the provided leading prefix string.
+// If s doesn't start with prefix, s is returned unchanged.
+func TrimPrefix(s, prefix string) string {
+	if HasPrefix(s, prefix) {
+		return s[len(prefix):]
+	}
+	return s
+}
+
+// TrimSuffix returns s without the provided trailing suffix string.
+// If s doesn't end with suffix, s is returned unchanged.
+func TrimSuffix(s, suffix string) string {
+	if HasSuffix(s, suffix) {
+		return s[:len(s)-len(suffix)]
+	}
+	return s
+}
+
+// Replace returns a copy of the string s with the first n
+// non-overlapping instances of old replaced by new.
+// If old is empty, it matches at the beginning of the string
+// and after each UTF-8 sequence, yielding up to k+1 replacements
+// for a k-rune string.
+// If n < 0, there is no limit on the number of replacements.
+func Replace(s, old, new string, n int) string {
+	if old == new || n == 0 {
+		return s // avoid allocation
+	}
+
+	// Compute number of replacements.
+	if m := Count(s, old); m == 0 {
+		return s // avoid allocation
+	} else if n < 0 || m < n {
+		n = m
+	}
+
+	// Apply replacements to buffer.
+	var b Builder
+	b.Grow(len(s) + n*(len(new)-len(old)))
+	start := 0
+	for i := 0; i < n; i++ {
+		j := start
+		if len(old) == 0 {
+			if i > 0 {
+				_, wid := utf8.DecodeRuneInString(s[start:])
+				j += wid
+			}
+		} else {
+			j += Index(s[start:], old)
+		}
+		b.WriteString(s[start:j])
+		b.WriteString(new)
+		start = j + len(old)
+	}
+	b.WriteString(s[start:])
+	return b.String()
+}
+
+// ReplaceAll returns a copy of the string s with all
+// non-overlapping instances of old replaced by new.
+// If old is empty, it matches at the beginning of the string
+// and after each UTF-8 sequence, yielding up to k+1 replacements
+// for a k-rune string.
+func ReplaceAll(s, old, new string) string {
+	return Replace(s, old, new, -1)
+}
+
+// EqualFold reports whether s and t, interpreted as UTF-8 strings,
+// are equal under simple Unicode case-folding, which is a more general
+// form of case-insensitivity.
+func EqualFold(s, t string) bool {
+	for s != "" && t != "" {
+		// Extract first rune from each string.
+		var sr, tr rune
+		if s[0] < utf8.RuneSelf {
+			sr, s = rune(s[0]), s[1:]
+		} else {
+			r, size := utf8.DecodeRuneInString(s)
+			sr, s = r, s[size:]
+		}
+		if t[0] < utf8.RuneSelf {
+			tr, t = rune(t[0]), t[1:]
+		} else {
+			r, size := utf8.DecodeRuneInString(t)
+			tr, t = r, t[size:]
+		}
+
+		// If they match, keep going; if not, return false.
+
+		// Easy case.
+		if tr == sr {
+			continue
+		}
+
+		// Make sr < tr to simplify what follows.
+		if tr < sr {
+			tr, sr = sr, tr
+		}
+		// Fast check for ASCII.
+		if tr < utf8.RuneSelf {
+			// ASCII only, sr/tr must be upper/lower case
+			if 'A' <= sr && sr <= 'Z' && tr == sr+'a'-'A' {
+				continue
+			}
+			return false
+		}
+
+		// General case. SimpleFold(x) returns the next equivalent rune > x
+		// or wraps around to smaller values.
+		r := unicode.SimpleFold(sr)
+		for r != sr && r < tr {
+			r = unicode.SimpleFold(r)
+		}
+		if r == tr {
+			continue
+		}
+		return false
+	}
+
+	// One string is empty. Are both?
+	return s == t
+}
+
+// Index returns the index of the first instance of substr in s, or -1 if substr is not present in s.
+func Index(s, substr string) int {
+	n := len(substr)
+	switch {
+	case n == 0:
+		return 0
+	case n == 1:
+		return IndexByte(s, substr[0])
+	case n == len(s):
+		if substr == s {
+			return 0
+		}
+		return -1
+	case n > len(s):
+		return -1
+	case n <= bytealg.MaxLen:
+		// Use brute force when s and substr both are small
+		if len(s) <= bytealg.MaxBruteForce {
+			return bytealg.IndexString(s, substr)
+		}
+		c0 := substr[0]
+		c1 := substr[1]
+		i := 0
+		t := len(s) - n + 1
+		fails := 0
+		for i < t {
+			if s[i] != c0 {
+				// IndexByte is faster than bytealg.IndexString, so use it as long as
+				// we're not getting lots of false positives.
+				o := IndexByte(s[i+1:t], c0)
+				if o < 0 {
+					return -1
+				}
+				i += o + 1
+			}
+			if s[i+1] == c1 && s[i:i+n] == substr {
+				return i
+			}
+			fails++
+			i++
+			// Switch to bytealg.IndexString when IndexByte produces too many false positives.
+			if fails > bytealg.Cutover(i) {
+				r := bytealg.IndexString(s[i:], substr)
+				if r >= 0 {
+					return r + i
+				}
+				return -1
+			}
+		}
+		return -1
+	}
+	c0 := substr[0]
+	c1 := substr[1]
+	i := 0
+	t := len(s) - n + 1
+	fails := 0
+	for i < t {
+		if s[i] != c0 {
+			o := IndexByte(s[i+1:t], c0)
+			if o < 0 {
+				return -1
+			}
+			i += o + 1
+		}
+		if s[i+1] == c1 && s[i:i+n] == substr {
+			return i
+		}
+		i++
+		fails++
+		if fails >= 4+i>>4 && i < t {
+			// See comment in ../bytes/bytes.go.
+			j := bytealg.IndexRabinKarp(s[i:], substr)
+			if j < 0 {
+				return -1
+			}
+			return i + j
+		}
+	}
+	return -1
+}
+
+// Cut slices s around the first instance of sep,
+// returning the text before and after sep.
+// The found result reports whether sep appears in s.
+// If sep does not appear in s, cut returns s, "", false.
+func Cut(s, sep string) (before, after string, found bool) {
+	if i := Index(s, sep); i >= 0 {
+		return s[:i], s[i+len(sep):], true
+	}
+	return s, "", false
+}
diff --git a/contrib/go/_std_1.18/src/sync/atomic/asm.s b/contrib/go/_std_1.19/src/sync/atomic/asm.s
index 2022304665..2022304665 100644
--- a/contrib/go/_std_1.18/src/sync/atomic/asm.s
+++ b/contrib/go/_std_1.19/src/sync/atomic/asm.s
diff --git a/contrib/go/_std_1.19/src/sync/atomic/doc.go b/contrib/go/_std_1.19/src/sync/atomic/doc.go
new file mode 100644
index 0000000000..7977d13168
--- /dev/null
+++ b/contrib/go/_std_1.19/src/sync/atomic/doc.go
@@ -0,0 +1,153 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package atomic provides low-level atomic memory primitives
+// useful for implementing synchronization algorithms.
+//
+// These functions require great care to be used correctly.
+// Except for special, low-level applications, synchronization is better
+// done with channels or the facilities of the sync package.
+// Share memory by communicating;
+// don't communicate by sharing memory.
+//
+// The swap operation, implemented by the SwapT functions, is the atomic
+// equivalent of:
+//
+//	old = *addr
+//	*addr = new
+//	return old
+//
+// The compare-and-swap operation, implemented by the CompareAndSwapT
+// functions, is the atomic equivalent of:
+//
+//	if *addr == old {
+//		*addr = new
+//		return true
+//	}
+//	return false
+//
+// The add operation, implemented by the AddT functions, is the atomic
+// equivalent of:
+//
+//	*addr += delta
+//	return *addr
+//
+// The load and store operations, implemented by the LoadT and StoreT
+// functions, are the atomic equivalents of "return *addr" and
+// "*addr = val".
+//
+// In the terminology of the Go memory model, if the effect of
+// an atomic operation A is observed by atomic operation B,
+// then A “synchronizes before” B.
+// Additionally, all the atomic operations executed in a program
+// behave as though executed in some sequentially consistent order.
+// This definition provides the same semantics as
+// C++'s sequentially consistent atomics and Java's volatile variables.
+package atomic
+
+import (
+	"unsafe"
+)
+
+// BUG(rsc): On 386, the 64-bit functions use instructions unavailable before the Pentium MMX.
+//
+// On non-Linux ARM, the 64-bit functions use instructions unavailable before the ARMv6k core.
+//
+// On ARM, 386, and 32-bit MIPS, it is the caller's responsibility to arrange
+// for 64-bit alignment of 64-bit words accessed atomically via the primitive
+// atomic functions (types Int64 and Uint64 are automatically aligned).
+// The first word in an allocated struct, array, or slice; in a global
+// variable; or in a local variable (because the subject of all atomic operations
+// will escape to the heap) can be relied upon to be 64-bit aligned.
+
+// SwapInt32 atomically stores new into *addr and returns the previous *addr value.
+func SwapInt32(addr *int32, new int32) (old int32)
+
+// SwapInt64 atomically stores new into *addr and returns the previous *addr value.
+func SwapInt64(addr *int64, new int64) (old int64)
+
+// SwapUint32 atomically stores new into *addr and returns the previous *addr value.
+func SwapUint32(addr *uint32, new uint32) (old uint32)
+
+// SwapUint64 atomically stores new into *addr and returns the previous *addr value.
+func SwapUint64(addr *uint64, new uint64) (old uint64)
+
+// SwapUintptr atomically stores new into *addr and returns the previous *addr value.
+func SwapUintptr(addr *uintptr, new uintptr) (old uintptr)
+
+// SwapPointer atomically stores new into *addr and returns the previous *addr value.
+func SwapPointer(addr *unsafe.Pointer, new unsafe.Pointer) (old unsafe.Pointer)
+
+// CompareAndSwapInt32 executes the compare-and-swap operation for an int32 value.
+func CompareAndSwapInt32(addr *int32, old, new int32) (swapped bool)
+
+// CompareAndSwapInt64 executes the compare-and-swap operation for an int64 value.
+func CompareAndSwapInt64(addr *int64, old, new int64) (swapped bool)
+
+// CompareAndSwapUint32 executes the compare-and-swap operation for a uint32 value.
+func CompareAndSwapUint32(addr *uint32, old, new uint32) (swapped bool)
+
+// CompareAndSwapUint64 executes the compare-and-swap operation for a uint64 value.
+func CompareAndSwapUint64(addr *uint64, old, new uint64) (swapped bool)
+
+// CompareAndSwapUintptr executes the compare-and-swap operation for a uintptr value.
+func CompareAndSwapUintptr(addr *uintptr, old, new uintptr) (swapped bool)
+
+// CompareAndSwapPointer executes the compare-and-swap operation for a unsafe.Pointer value.
+func CompareAndSwapPointer(addr *unsafe.Pointer, old, new unsafe.Pointer) (swapped bool)
+
+// AddInt32 atomically adds delta to *addr and returns the new value.
+func AddInt32(addr *int32, delta int32) (new int32)
+
+// AddUint32 atomically adds delta to *addr and returns the new value.
+// To subtract a signed positive constant value c from x, do AddUint32(&x, ^uint32(c-1)).
+// In particular, to decrement x, do AddUint32(&x, ^uint32(0)).
+func AddUint32(addr *uint32, delta uint32) (new uint32)
+
+// AddInt64 atomically adds delta to *addr and returns the new value.
+func AddInt64(addr *int64, delta int64) (new int64)
+
+// AddUint64 atomically adds delta to *addr and returns the new value.
+// To subtract a signed positive constant value c from x, do AddUint64(&x, ^uint64(c-1)).
+// In particular, to decrement x, do AddUint64(&x, ^uint64(0)).
+func AddUint64(addr *uint64, delta uint64) (new uint64)
+
+// AddUintptr atomically adds delta to *addr and returns the new value.
+func AddUintptr(addr *uintptr, delta uintptr) (new uintptr)
+
+// LoadInt32 atomically loads *addr.
+func LoadInt32(addr *int32) (val int32)
+
+// LoadInt64 atomically loads *addr.
+func LoadInt64(addr *int64) (val int64)
+
+// LoadUint32 atomically loads *addr.
+func LoadUint32(addr *uint32) (val uint32)
+
+// LoadUint64 atomically loads *addr.
+func LoadUint64(addr *uint64) (val uint64)
+
+// LoadUintptr atomically loads *addr.
+func LoadUintptr(addr *uintptr) (val uintptr)
+
+// LoadPointer atomically loads *addr.
+func LoadPointer(addr *unsafe.Pointer) (val unsafe.Pointer)
+
+// StoreInt32 atomically stores val into *addr.
+func StoreInt32(addr *int32, val int32)
+
+// StoreInt64 atomically stores val into *addr.
+func StoreInt64(addr *int64, val int64)
+
+// StoreUint32 atomically stores val into *addr.
+func StoreUint32(addr *uint32, val uint32)
+
+// StoreUint64 atomically stores val into *addr.
+func StoreUint64(addr *uint64, val uint64)
+
+// StoreUintptr atomically stores val into *addr.
+func StoreUintptr(addr *uintptr, val uintptr)
+
+// StorePointer atomically stores val into *addr.
+func StorePointer(addr *unsafe.Pointer, val unsafe.Pointer)
diff --git a/contrib/go/_std_1.19/src/sync/atomic/type.go b/contrib/go/_std_1.19/src/sync/atomic/type.go
new file mode 100644
index 0000000000..f7b8f5a3b7
--- /dev/null
+++ b/contrib/go/_std_1.19/src/sync/atomic/type.go
@@ -0,0 +1,191 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package atomic
+
+import "unsafe"
+
+// A Bool is an atomic boolean value.
+// The zero value is false.
+type Bool struct {
+	_ noCopy
+	v uint32
+}
+
+// Load atomically loads and returns the value stored in x.
+func (x *Bool) Load() bool { return LoadUint32(&x.v) != 0 }
+
+// Store atomically stores val into x.
+func (x *Bool) Store(val bool) { StoreUint32(&x.v, b32(val)) }
+
+// Swap atomically stores new into x and returns the previous value.
+func (x *Bool) Swap(new bool) (old bool) { return SwapUint32(&x.v, b32(new)) != 0 }
+
+// CompareAndSwap executes the compare-and-swap operation for the boolean value x.
+func (x *Bool) CompareAndSwap(old, new bool) (swapped bool) {
+	return CompareAndSwapUint32(&x.v, b32(old), b32(new))
+}
+
+// b32 returns a uint32 0 or 1 representing b.
+func b32(b bool) uint32 {
+	if b {
+		return 1
+	}
+	return 0
+}
+
+// A Pointer is an atomic pointer of type *T. The zero value is a nil *T.
+type Pointer[T any] struct {
+	_ noCopy
+	v unsafe.Pointer
+}
+
+// Load atomically loads and returns the value stored in x.
+func (x *Pointer[T]) Load() *T { return (*T)(LoadPointer(&x.v)) }
+
+// Store atomically stores val into x.
+func (x *Pointer[T]) Store(val *T) { StorePointer(&x.v, unsafe.Pointer(val)) }
+
+// Swap atomically stores new into x and returns the previous value.
+func (x *Pointer[T]) Swap(new *T) (old *T) { return (*T)(SwapPointer(&x.v, unsafe.Pointer(new))) }
+
+// CompareAndSwap executes the compare-and-swap operation for x.
+func (x *Pointer[T]) CompareAndSwap(old, new *T) (swapped bool) {
+	return CompareAndSwapPointer(&x.v, unsafe.Pointer(old), unsafe.Pointer(new))
+}
+
+// An Int32 is an atomic int32. The zero value is zero.
+type Int32 struct {
+	_ noCopy
+	v int32
+}
+
+// Load atomically loads and returns the value stored in x.
+func (x *Int32) Load() int32 { return LoadInt32(&x.v) }
+
+// Store atomically stores val into x.
+func (x *Int32) Store(val int32) { StoreInt32(&x.v, val) }
+
+// Swap atomically stores new into x and returns the previous value.
+func (x *Int32) Swap(new int32) (old int32) { return SwapInt32(&x.v, new) }
+
+// CompareAndSwap executes the compare-and-swap operation for x.
+func (x *Int32) CompareAndSwap(old, new int32) (swapped bool) {
+	return CompareAndSwapInt32(&x.v, old, new)
+}
+
+// Add atomically adds delta to x and returns the new value.
+func (x *Int32) Add(delta int32) (new int32) { return AddInt32(&x.v, delta) }
+
+// An Int64 is an atomic int64. The zero value is zero.
+type Int64 struct {
+	_ noCopy
+	_ align64
+	v int64
+}
+
+// Load atomically loads and returns the value stored in x.
+func (x *Int64) Load() int64 { return LoadInt64(&x.v) }
+
+// Store atomically stores val into x.
+func (x *Int64) Store(val int64) { StoreInt64(&x.v, val) }
+
+// Swap atomically stores new into x and returns the previous value.
+func (x *Int64) Swap(new int64) (old int64) { return SwapInt64(&x.v, new) }
+
+// CompareAndSwap executes the compare-and-swap operation for x.
+func (x *Int64) CompareAndSwap(old, new int64) (swapped bool) {
+	return CompareAndSwapInt64(&x.v, old, new)
+}
+
+// Add atomically adds delta to x and returns the new value.
+func (x *Int64) Add(delta int64) (new int64) { return AddInt64(&x.v, delta) }
+
+// An Uint32 is an atomic uint32. The zero value is zero.
+type Uint32 struct {
+	_ noCopy
+	v uint32
+}
+
+// Load atomically loads and returns the value stored in x.
+func (x *Uint32) Load() uint32 { return LoadUint32(&x.v) }
+
+// Store atomically stores val into x.
+func (x *Uint32) Store(val uint32) { StoreUint32(&x.v, val) }
+
+// Swap atomically stores new into x and returns the previous value.
+func (x *Uint32) Swap(new uint32) (old uint32) { return SwapUint32(&x.v, new) }
+
+// CompareAndSwap executes the compare-and-swap operation for x.
+func (x *Uint32) CompareAndSwap(old, new uint32) (swapped bool) {
+	return CompareAndSwapUint32(&x.v, old, new)
+}
+
+// Add atomically adds delta to x and returns the new value.
+func (x *Uint32) Add(delta uint32) (new uint32) { return AddUint32(&x.v, delta) }
+
+// An Uint64 is an atomic uint64. The zero value is zero.
+type Uint64 struct {
+	_ noCopy
+	_ align64
+	v uint64
+}
+
+// Load atomically loads and returns the value stored in x.
+func (x *Uint64) Load() uint64 { return LoadUint64(&x.v) }
+
+// Store atomically stores val into x.
+func (x *Uint64) Store(val uint64) { StoreUint64(&x.v, val) }
+
+// Swap atomically stores new into x and returns the previous value.
+func (x *Uint64) Swap(new uint64) (old uint64) { return SwapUint64(&x.v, new) }
+
+// CompareAndSwap executes the compare-and-swap operation for x.
+func (x *Uint64) CompareAndSwap(old, new uint64) (swapped bool) {
+	return CompareAndSwapUint64(&x.v, old, new)
+}
+
+// Add atomically adds delta to x and returns the new value.
+func (x *Uint64) Add(delta uint64) (new uint64) { return AddUint64(&x.v, delta) }
+
+// An Uintptr is an atomic uintptr. The zero value is zero.
+type Uintptr struct {
+	_ noCopy
+	v uintptr
+}
+
+// Load atomically loads and returns the value stored in x.
+func (x *Uintptr) Load() uintptr { return LoadUintptr(&x.v) }
+
+// Store atomically stores val into x.
+func (x *Uintptr) Store(val uintptr) { StoreUintptr(&x.v, val) }
+
+// Swap atomically stores new into x and returns the previous value.
+func (x *Uintptr) Swap(new uintptr) (old uintptr) { return SwapUintptr(&x.v, new) }
+
+// CompareAndSwap executes the compare-and-swap operation for x.
+func (x *Uintptr) CompareAndSwap(old, new uintptr) (swapped bool) {
+	return CompareAndSwapUintptr(&x.v, old, new)
+}
+
+// Add atomically adds delta to x and returns the new value.
+func (x *Uintptr) Add(delta uintptr) (new uintptr) { return AddUintptr(&x.v, delta) }
+
+// noCopy may be added to structs which must not be copied
+// after the first use.
+//
+// See https://golang.org/issues/8005#issuecomment-190753527
+// for details.
+//
+// Note that it must not be embedded, due to the Lock and Unlock methods.
+type noCopy struct{}
+
+// Lock is a no-op used by -copylocks checker from `go vet`.
+func (*noCopy) Lock()   {}
+func (*noCopy) Unlock() {}
+
+// align64 may be added to structs that must be 64-bit aligned.
+// This struct is recognized by a special case in the compiler
+// and will not work if copied to any other package.
+type align64 struct{}
diff --git a/contrib/go/_std_1.18/src/sync/atomic/value.go b/contrib/go/_std_1.19/src/sync/atomic/value.go
index 88315f2d88..88315f2d88 100644
--- a/contrib/go/_std_1.18/src/sync/atomic/value.go
+++ b/contrib/go/_std_1.19/src/sync/atomic/value.go
diff --git a/contrib/go/_std_1.19/src/sync/cond.go b/contrib/go/_std_1.19/src/sync/cond.go
new file mode 100644
index 0000000000..cbf5ba6071
--- /dev/null
+++ b/contrib/go/_std_1.19/src/sync/cond.go
@@ -0,0 +1,117 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package sync
+
+import (
+	"sync/atomic"
+	"unsafe"
+)
+
+// Cond implements a condition variable, a rendezvous point
+// for goroutines waiting for or announcing the occurrence
+// of an event.
+//
+// Each Cond has an associated Locker L (often a *Mutex or *RWMutex),
+// which must be held when changing the condition and
+// when calling the Wait method.
+//
+// A Cond must not be copied after first use.
+//
+// In the terminology of the Go memory model, Cond arranges that
+// a call to Broadcast or Signal “synchronizes before” any Wait call
+// that it unblocks.
+//
+// For many simple use cases, users will be better off using channels than a
+// Cond (Broadcast corresponds to closing a channel, and Signal corresponds to
+// sending on a channel).
+//
+// For more on replacements for sync.Cond, see [Roberto Clapis's series on
+// advanced concurrency patterns], as well as [Bryan Mills's talk on concurrency
+// patterns].
+//
+// [Roberto Clapis's series on advanced concurrency patterns]: https://blogtitle.github.io/categories/concurrency/
+// [Bryan Mills's talk on concurrency patterns]: https://drive.google.com/file/d/1nPdvhB0PutEJzdCq5ms6UI58dp50fcAN/view
+type Cond struct {
+	noCopy noCopy
+
+	// L is held while observing or changing the condition
+	L Locker
+
+	notify  notifyList
+	checker copyChecker
+}
+
+// NewCond returns a new Cond with Locker l.
+func NewCond(l Locker) *Cond {
+	return &Cond{L: l}
+}
+
+// Wait atomically unlocks c.L and suspends execution
+// of the calling goroutine. After later resuming execution,
+// Wait locks c.L before returning. Unlike in other systems,
+// Wait cannot return unless awoken by Broadcast or Signal.
+//
+// Because c.L is not locked when Wait first resumes, the caller
+// typically cannot assume that the condition is true when
+// Wait returns. Instead, the caller should Wait in a loop:
+//
+//	c.L.Lock()
+//	for !condition() {
+//	    c.Wait()
+//	}
+//	... make use of condition ...
+//	c.L.Unlock()
+func (c *Cond) Wait() {
+	c.checker.check()
+	t := runtime_notifyListAdd(&c.notify)
+	c.L.Unlock()
+	runtime_notifyListWait(&c.notify, t)
+	c.L.Lock()
+}
+
+// Signal wakes one goroutine waiting on c, if there is any.
+//
+// It is allowed but not required for the caller to hold c.L
+// during the call.
+//
+// Signal() does not affect goroutine scheduling priority; if other goroutines
+// are attempting to lock c.L, they may be awoken before a "waiting" goroutine.
+func (c *Cond) Signal() {
+	c.checker.check()
+	runtime_notifyListNotifyOne(&c.notify)
+}
+
+// Broadcast wakes all goroutines waiting on c.
+//
+// It is allowed but not required for the caller to hold c.L
+// during the call.
+func (c *Cond) Broadcast() {
+	c.checker.check()
+	runtime_notifyListNotifyAll(&c.notify)
+}
+
+// copyChecker holds back pointer to itself to detect object copying.
+type copyChecker uintptr
+
+func (c *copyChecker) check() {
+	if uintptr(*c) != uintptr(unsafe.Pointer(c)) &&
+		!atomic.CompareAndSwapUintptr((*uintptr)(c), 0, uintptr(unsafe.Pointer(c))) &&
+		uintptr(*c) != uintptr(unsafe.Pointer(c)) {
+		panic("sync.Cond is copied")
+	}
+}
+
+// noCopy may be added to structs which must not be copied
+// after the first use.
+//
+// See https://golang.org/issues/8005#issuecomment-190753527
+// for details.
+//
+// Note that it must not be embedded, due to the Lock and Unlock methods.
+type noCopy struct{}
+
+// Lock is a no-op used by -copylocks checker from `go vet`.
+func (*noCopy) Lock()   {}
+func (*noCopy) Unlock() {}
diff --git a/contrib/go/_std_1.19/src/sync/map.go b/contrib/go/_std_1.19/src/sync/map.go
new file mode 100644
index 0000000000..ec529e056b
--- /dev/null
+++ b/contrib/go/_std_1.19/src/sync/map.go
@@ -0,0 +1,393 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package sync
+
+import (
+	"sync/atomic"
+	"unsafe"
+)
+
+// Map is like a Go map[interface{}]interface{} but is safe for concurrent use
+// by multiple goroutines without additional locking or coordination.
+// Loads, stores, and deletes run in amortized constant time.
+//
+// The Map type is specialized. Most code should use a plain Go map instead,
+// with separate locking or coordination, for better type safety and to make it
+// easier to maintain other invariants along with the map content.
+//
+// The Map type is optimized for two common use cases: (1) when the entry for a given
+// key is only ever written once but read many times, as in caches that only grow,
+// or (2) when multiple goroutines read, write, and overwrite entries for disjoint
+// sets of keys. In these two cases, use of a Map may significantly reduce lock
+// contention compared to a Go map paired with a separate Mutex or RWMutex.
+//
+// The zero Map is empty and ready for use. A Map must not be copied after first use.
+//
+// In the terminology of the Go memory model, Map arranges that a write operation
+// “synchronizes before” any read operation that observes the effect of the write, where
+// read and write operations are defined as follows.
+// Load, LoadAndDelete, LoadOrStore are read operations;
+// Delete, LoadAndDelete, and Store are write operations;
+// and LoadOrStore is a write operation when it returns loaded set to false.
+type Map struct {
+	mu Mutex
+
+	// read contains the portion of the map's contents that are safe for
+	// concurrent access (with or without mu held).
+	//
+	// The read field itself is always safe to load, but must only be stored with
+	// mu held.
+	//
+	// Entries stored in read may be updated concurrently without mu, but updating
+	// a previously-expunged entry requires that the entry be copied to the dirty
+	// map and unexpunged with mu held.
+	read atomic.Value // readOnly
+
+	// dirty contains the portion of the map's contents that require mu to be
+	// held. To ensure that the dirty map can be promoted to the read map quickly,
+	// it also includes all of the non-expunged entries in the read map.
+	//
+	// Expunged entries are not stored in the dirty map. An expunged entry in the
+	// clean map must be unexpunged and added to the dirty map before a new value
+	// can be stored to it.
+	//
+	// If the dirty map is nil, the next write to the map will initialize it by
+	// making a shallow copy of the clean map, omitting stale entries.
+	dirty map[any]*entry
+
+	// misses counts the number of loads since the read map was last updated that
+	// needed to lock mu to determine whether the key was present.
+	//
+	// Once enough misses have occurred to cover the cost of copying the dirty
+	// map, the dirty map will be promoted to the read map (in the unamended
+	// state) and the next store to the map will make a new dirty copy.
+	misses int
+}
+
+// readOnly is an immutable struct stored atomically in the Map.read field.
+type readOnly struct {
+	m       map[any]*entry
+	amended bool // true if the dirty map contains some key not in m.
+}
+
+// expunged is an arbitrary pointer that marks entries which have been deleted
+// from the dirty map.
+var expunged = unsafe.Pointer(new(any))
+
+// An entry is a slot in the map corresponding to a particular key.
+type entry struct {
+	// p points to the interface{} value stored for the entry.
+	//
+	// If p == nil, the entry has been deleted, and either m.dirty == nil or
+	// m.dirty[key] is e.
+	//
+	// If p == expunged, the entry has been deleted, m.dirty != nil, and the entry
+	// is missing from m.dirty.
+	//
+	// Otherwise, the entry is valid and recorded in m.read.m[key] and, if m.dirty
+	// != nil, in m.dirty[key].
+	//
+	// An entry can be deleted by atomic replacement with nil: when m.dirty is
+	// next created, it will atomically replace nil with expunged and leave
+	// m.dirty[key] unset.
+	//
+	// An entry's associated value can be updated by atomic replacement, provided
+	// p != expunged. If p == expunged, an entry's associated value can be updated
+	// only after first setting m.dirty[key] = e so that lookups using the dirty
+	// map find the entry.
+	p unsafe.Pointer // *interface{}
+}
+
+func newEntry(i any) *entry {
+	return &entry{p: unsafe.Pointer(&i)}
+}
+
+// Load returns the value stored in the map for a key, or nil if no
+// value is present.
+// The ok result indicates whether value was found in the map.
+func (m *Map) Load(key any) (value any, ok bool) {
+	read, _ := m.read.Load().(readOnly)
+	e, ok := read.m[key]
+	if !ok && read.amended {
+		m.mu.Lock()
+		// Avoid reporting a spurious miss if m.dirty got promoted while we were
+		// blocked on m.mu. (If further loads of the same key will not miss, it's
+		// not worth copying the dirty map for this key.)
+		read, _ = m.read.Load().(readOnly)
+		e, ok = read.m[key]
+		if !ok && read.amended {
+			e, ok = m.dirty[key]
+			// Regardless of whether the entry was present, record a miss: this key
+			// will take the slow path until the dirty map is promoted to the read
+			// map.
+			m.missLocked()
+		}
+		m.mu.Unlock()
+	}
+	if !ok {
+		return nil, false
+	}
+	return e.load()
+}
+
+func (e *entry) load() (value any, ok bool) {
+	p := atomic.LoadPointer(&e.p)
+	if p == nil || p == expunged {
+		return nil, false
+	}
+	return *(*any)(p), true
+}
+
+// Store sets the value for a key.
+func (m *Map) Store(key, value any) {
+	read, _ := m.read.Load().(readOnly)
+	if e, ok := read.m[key]; ok && e.tryStore(&value) {
+		return
+	}
+
+	m.mu.Lock()
+	read, _ = m.read.Load().(readOnly)
+	if e, ok := read.m[key]; ok {
+		if e.unexpungeLocked() {
+			// The entry was previously expunged, which implies that there is a
+			// non-nil dirty map and this entry is not in it.
+			m.dirty[key] = e
+		}
+		e.storeLocked(&value)
+	} else if e, ok := m.dirty[key]; ok {
+		e.storeLocked(&value)
+	} else {
+		if !read.amended {
+			// We're adding the first new key to the dirty map.
+			// Make sure it is allocated and mark the read-only map as incomplete.
+			m.dirtyLocked()
+			m.read.Store(readOnly{m: read.m, amended: true})
+		}
+		m.dirty[key] = newEntry(value)
+	}
+	m.mu.Unlock()
+}
+
+// tryStore stores a value if the entry has not been expunged.
+//
+// If the entry is expunged, tryStore returns false and leaves the entry
+// unchanged.
+func (e *entry) tryStore(i *any) bool {
+	for {
+		p := atomic.LoadPointer(&e.p)
+		if p == expunged {
+			return false
+		}
+		if atomic.CompareAndSwapPointer(&e.p, p, unsafe.Pointer(i)) {
+			return true
+		}
+	}
+}
+
+// unexpungeLocked ensures that the entry is not marked as expunged.
+//
+// If the entry was previously expunged, it must be added to the dirty map
+// before m.mu is unlocked.
+func (e *entry) unexpungeLocked() (wasExpunged bool) {
+	return atomic.CompareAndSwapPointer(&e.p, expunged, nil)
+}
+
+// storeLocked unconditionally stores a value to the entry.
+//
+// The entry must be known not to be expunged.
+func (e *entry) storeLocked(i *any) {
+	atomic.StorePointer(&e.p, unsafe.Pointer(i))
+}
+
+// LoadOrStore returns the existing value for the key if present.
+// Otherwise, it stores and returns the given value.
+// The loaded result is true if the value was loaded, false if stored.
+func (m *Map) LoadOrStore(key, value any) (actual any, loaded bool) {
+	// Avoid locking if it's a clean hit.
+	read, _ := m.read.Load().(readOnly)
+	if e, ok := read.m[key]; ok {
+		actual, loaded, ok := e.tryLoadOrStore(value)
+		if ok {
+			return actual, loaded
+		}
+	}
+
+	m.mu.Lock()
+	read, _ = m.read.Load().(readOnly)
+	if e, ok := read.m[key]; ok {
+		if e.unexpungeLocked() {
+			m.dirty[key] = e
+		}
+		actual, loaded, _ = e.tryLoadOrStore(value)
+	} else if e, ok := m.dirty[key]; ok {
+		actual, loaded, _ = e.tryLoadOrStore(value)
+		m.missLocked()
+	} else {
+		if !read.amended {
+			// We're adding the first new key to the dirty map.
+			// Make sure it is allocated and mark the read-only map as incomplete.
+			m.dirtyLocked()
+			m.read.Store(readOnly{m: read.m, amended: true})
+		}
+		m.dirty[key] = newEntry(value)
+		actual, loaded = value, false
+	}
+	m.mu.Unlock()
+
+	return actual, loaded
+}
+
+// tryLoadOrStore atomically loads or stores a value if the entry is not
+// expunged.
+//
+// If the entry is expunged, tryLoadOrStore leaves the entry unchanged and
+// returns with ok==false.
+func (e *entry) tryLoadOrStore(i any) (actual any, loaded, ok bool) {
+	p := atomic.LoadPointer(&e.p)
+	if p == expunged {
+		return nil, false, false
+	}
+	if p != nil {
+		return *(*any)(p), true, true
+	}
+
+	// Copy the interface after the first load to make this method more amenable
+	// to escape analysis: if we hit the "load" path or the entry is expunged, we
+	// shouldn't bother heap-allocating.
+	ic := i
+	for {
+		if atomic.CompareAndSwapPointer(&e.p, nil, unsafe.Pointer(&ic)) {
+			return i, false, true
+		}
+		p = atomic.LoadPointer(&e.p)
+		if p == expunged {
+			return nil, false, false
+		}
+		if p != nil {
+			return *(*any)(p), true, true
+		}
+	}
+}
+
+// LoadAndDelete deletes the value for a key, returning the previous value if any.
+// The loaded result reports whether the key was present.
+func (m *Map) LoadAndDelete(key any) (value any, loaded bool) {
+	read, _ := m.read.Load().(readOnly)
+	e, ok := read.m[key]
+	if !ok && read.amended {
+		m.mu.Lock()
+		read, _ = m.read.Load().(readOnly)
+		e, ok = read.m[key]
+		if !ok && read.amended {
+			e, ok = m.dirty[key]
+			delete(m.dirty, key)
+			// Regardless of whether the entry was present, record a miss: this key
+			// will take the slow path until the dirty map is promoted to the read
+			// map.
+			m.missLocked()
+		}
+		m.mu.Unlock()
+	}
+	if ok {
+		return e.delete()
+	}
+	return nil, false
+}
+
+// Delete deletes the value for a key.
+func (m *Map) Delete(key any) {
+	m.LoadAndDelete(key)
+}
+
+func (e *entry) delete() (value any, ok bool) {
+	for {
+		p := atomic.LoadPointer(&e.p)
+		if p == nil || p == expunged {
+			return nil, false
+		}
+		if atomic.CompareAndSwapPointer(&e.p, p, nil) {
+			return *(*any)(p), true
+		}
+	}
+}
+
+// Range calls f sequentially for each key and value present in the map.
+// If f returns false, range stops the iteration.
+//
+// Range does not necessarily correspond to any consistent snapshot of the Map's
+// contents: no key will be visited more than once, but if the value for any key
+// is stored or deleted concurrently (including by f), Range may reflect any
+// mapping for that key from any point during the Range call. Range does not
+// block other methods on the receiver; even f itself may call any method on m.
+//
+// Range may be O(N) with the number of elements in the map even if f returns
+// false after a constant number of calls.
+func (m *Map) Range(f func(key, value any) bool) {
+	// We need to be able to iterate over all of the keys that were already
+	// present at the start of the call to Range.
+	// If read.amended is false, then read.m satisfies that property without
+	// requiring us to hold m.mu for a long time.
+	read, _ := m.read.Load().(readOnly)
+	if read.amended {
+		// m.dirty contains keys not in read.m. Fortunately, Range is already O(N)
+		// (assuming the caller does not break out early), so a call to Range
+		// amortizes an entire copy of the map: we can promote the dirty copy
+		// immediately!
+		m.mu.Lock()
+		read, _ = m.read.Load().(readOnly)
+		if read.amended {
+			read = readOnly{m: m.dirty}
+			m.read.Store(read)
+			m.dirty = nil
+			m.misses = 0
+		}
+		m.mu.Unlock()
+	}
+
+	for k, e := range read.m {
+		v, ok := e.load()
+		if !ok {
+			continue
+		}
+		if !f(k, v) {
+			break
+		}
+	}
+}
+
+func (m *Map) missLocked() {
+	m.misses++
+	if m.misses < len(m.dirty) {
+		return
+	}
+	m.read.Store(readOnly{m: m.dirty})
+	m.dirty = nil
+	m.misses = 0
+}
+
+func (m *Map) dirtyLocked() {
+	if m.dirty != nil {
+		return
+	}
+
+	read, _ := m.read.Load().(readOnly)
+	m.dirty = make(map[any]*entry, len(read.m))
+	for k, e := range read.m {
+		if !e.tryExpungeLocked() {
+			m.dirty[k] = e
+		}
+	}
+}
+
+func (e *entry) tryExpungeLocked() (isExpunged bool) {
+	p := atomic.LoadPointer(&e.p)
+	for p == nil {
+		if atomic.CompareAndSwapPointer(&e.p, nil, expunged) {
+			return true
+		}
+		p = atomic.LoadPointer(&e.p)
+	}
+	return p == expunged
+}
diff --git a/contrib/go/_std_1.19/src/sync/mutex.go b/contrib/go/_std_1.19/src/sync/mutex.go
new file mode 100644
index 0000000000..2ea024e585
--- /dev/null
+++ b/contrib/go/_std_1.19/src/sync/mutex.go
@@ -0,0 +1,259 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package sync provides basic synchronization primitives such as mutual
+// exclusion locks. Other than the Once and WaitGroup types, most are intended
+// for use by low-level library routines. Higher-level synchronization is
+// better done via channels and communication.
+//
+// Values containing the types defined in this package should not be copied.
+package sync
+
+import (
+	"internal/race"
+	"sync/atomic"
+	"unsafe"
+)
+
+// Provided by runtime via linkname.
+func throw(string)
+func fatal(string)
+
+// A Mutex is a mutual exclusion lock.
+// The zero value for a Mutex is an unlocked mutex.
+//
+// A Mutex must not be copied after first use.
+//
+// In the terminology of the Go memory model,
+// the n'th call to Unlock “synchronizes before” the m'th call to Lock
+// for any n < m.
+// A successful call to TryLock is equivalent to a call to Lock.
+// A failed call to TryLock does not establish any “synchronizes before”
+// relation at all.
+type Mutex struct {
+	state int32
+	sema  uint32
+}
+
+// A Locker represents an object that can be locked and unlocked.
+type Locker interface {
+	Lock()
+	Unlock()
+}
+
+const (
+	mutexLocked = 1 << iota // mutex is locked
+	mutexWoken
+	mutexStarving
+	mutexWaiterShift = iota
+
+	// Mutex fairness.
+	//
+	// Mutex can be in 2 modes of operations: normal and starvation.
+	// In normal mode waiters are queued in FIFO order, but a woken up waiter
+	// does not own the mutex and competes with new arriving goroutines over
+	// the ownership. New arriving goroutines have an advantage -- they are
+	// already running on CPU and there can be lots of them, so a woken up
+	// waiter has good chances of losing. In such case it is queued at front
+	// of the wait queue. If a waiter fails to acquire the mutex for more than 1ms,
+	// it switches mutex to the starvation mode.
+	//
+	// In starvation mode ownership of the mutex is directly handed off from
+	// the unlocking goroutine to the waiter at the front of the queue.
+	// New arriving goroutines don't try to acquire the mutex even if it appears
+	// to be unlocked, and don't try to spin. Instead they queue themselves at
+	// the tail of the wait queue.
+	//
+	// If a waiter receives ownership of the mutex and sees that either
+	// (1) it is the last waiter in the queue, or (2) it waited for less than 1 ms,
+	// it switches mutex back to normal operation mode.
+	//
+	// Normal mode has considerably better performance as a goroutine can acquire
+	// a mutex several times in a row even if there are blocked waiters.
+	// Starvation mode is important to prevent pathological cases of tail latency.
+	starvationThresholdNs = 1e6
+)
+
+// Lock locks m.
+// If the lock is already in use, the calling goroutine
+// blocks until the mutex is available.
+func (m *Mutex) Lock() {
+	// Fast path: grab unlocked mutex.
+	if atomic.CompareAndSwapInt32(&m.state, 0, mutexLocked) {
+		if race.Enabled {
+			race.Acquire(unsafe.Pointer(m))
+		}
+		return
+	}
+	// Slow path (outlined so that the fast path can be inlined)
+	m.lockSlow()
+}
+
+// TryLock tries to lock m and reports whether it succeeded.
+//
+// Note that while correct uses of TryLock do exist, they are rare,
+// and use of TryLock is often a sign of a deeper problem
+// in a particular use of mutexes.
+func (m *Mutex) TryLock() bool {
+	old := m.state
+	if old&(mutexLocked|mutexStarving) != 0 {
+		return false
+	}
+
+	// There may be a goroutine waiting for the mutex, but we are
+	// running now and can try to grab the mutex before that
+	// goroutine wakes up.
+	if !atomic.CompareAndSwapInt32(&m.state, old, old|mutexLocked) {
+		return false
+	}
+
+	if race.Enabled {
+		race.Acquire(unsafe.Pointer(m))
+	}
+	return true
+}
+
+func (m *Mutex) lockSlow() {
+	var waitStartTime int64
+	starving := false
+	awoke := false
+	iter := 0
+	old := m.state
+	for {
+		// Don't spin in starvation mode, ownership is handed off to waiters
+		// so we won't be able to acquire the mutex anyway.
+		if old&(mutexLocked|mutexStarving) == mutexLocked && runtime_canSpin(iter) {
+			// Active spinning makes sense.
+			// Try to set mutexWoken flag to inform Unlock
+			// to not wake other blocked goroutines.
+			if !awoke && old&mutexWoken == 0 && old>>mutexWaiterShift != 0 &&
+				atomic.CompareAndSwapInt32(&m.state, old, old|mutexWoken) {
+				awoke = true
+			}
+			runtime_doSpin()
+			iter++
+			old = m.state
+			continue
+		}
+		new := old
+		// Don't try to acquire starving mutex, new arriving goroutines must queue.
+		if old&mutexStarving == 0 {
+			new |= mutexLocked
+		}
+		if old&(mutexLocked|mutexStarving) != 0 {
+			new += 1 << mutexWaiterShift
+		}
+		// The current goroutine switches mutex to starvation mode.
+		// But if the mutex is currently unlocked, don't do the switch.
+		// Unlock expects that starving mutex has waiters, which will not
+		// be true in this case.
+		if starving && old&mutexLocked != 0 {
+			new |= mutexStarving
+		}
+		if awoke {
+			// The goroutine has been woken from sleep,
+			// so we need to reset the flag in either case.
+			if new&mutexWoken == 0 {
+				throw("sync: inconsistent mutex state")
+			}
+			new &^= mutexWoken
+		}
+		if atomic.CompareAndSwapInt32(&m.state, old, new) {
+			if old&(mutexLocked|mutexStarving) == 0 {
+				break // locked the mutex with CAS
+			}
+			// If we were already waiting before, queue at the front of the queue.
+			queueLifo := waitStartTime != 0
+			if waitStartTime == 0 {
+				waitStartTime = runtime_nanotime()
+			}
+			runtime_SemacquireMutex(&m.sema, queueLifo, 1)
+			starving = starving || runtime_nanotime()-waitStartTime > starvationThresholdNs
+			old = m.state
+			if old&mutexStarving != 0 {
+				// If this goroutine was woken and mutex is in starvation mode,
+				// ownership was handed off to us but mutex is in somewhat
+				// inconsistent state: mutexLocked is not set and we are still
+				// accounted as waiter. Fix that.
+				if old&(mutexLocked|mutexWoken) != 0 || old>>mutexWaiterShift == 0 {
+					throw("sync: inconsistent mutex state")
+				}
+				delta := int32(mutexLocked - 1<<mutexWaiterShift)
+				if !starving || old>>mutexWaiterShift == 1 {
+					// Exit starvation mode.
+					// Critical to do it here and consider wait time.
+					// Starvation mode is so inefficient, that two goroutines
+					// can go lock-step infinitely once they switch mutex
+					// to starvation mode.
+					delta -= mutexStarving
+				}
+				atomic.AddInt32(&m.state, delta)
+				break
+			}
+			awoke = true
+			iter = 0
+		} else {
+			old = m.state
+		}
+	}
+
+	if race.Enabled {
+		race.Acquire(unsafe.Pointer(m))
+	}
+}
+
+// Unlock unlocks m.
+// It is a run-time error if m is not locked on entry to Unlock.
+//
+// A locked Mutex is not associated with a particular goroutine.
+// It is allowed for one goroutine to lock a Mutex and then
+// arrange for another goroutine to unlock it.
+func (m *Mutex) Unlock() {
+	if race.Enabled {
+		_ = m.state
+		race.Release(unsafe.Pointer(m))
+	}
+
+	// Fast path: drop lock bit.
+	new := atomic.AddInt32(&m.state, -mutexLocked)
+	if new != 0 {
+		// Outlined slow path to allow inlining the fast path.
+		// To hide unlockSlow during tracing we skip one extra frame when tracing GoUnblock.
+		m.unlockSlow(new)
+	}
+}
+
+func (m *Mutex) unlockSlow(new int32) {
+	if (new+mutexLocked)&mutexLocked == 0 {
+		fatal("sync: unlock of unlocked mutex")
+	}
+	if new&mutexStarving == 0 {
+		old := new
+		for {
+			// If there are no waiters or a goroutine has already
+			// been woken or grabbed the lock, no need to wake anyone.
+			// In starvation mode ownership is directly handed off from unlocking
+			// goroutine to the next waiter. We are not part of this chain,
+			// since we did not observe mutexStarving when we unlocked the mutex above.
+			// So get off the way.
+			if old>>mutexWaiterShift == 0 || old&(mutexLocked|mutexWoken|mutexStarving) != 0 {
+				return
+			}
+			// Grab the right to wake someone.
+			new = (old - 1<<mutexWaiterShift) | mutexWoken
+			if atomic.CompareAndSwapInt32(&m.state, old, new) {
+				runtime_Semrelease(&m.sema, false, 1)
+				return
+			}
+			old = m.state
+		}
+	} else {
+		// Starving mode: handoff mutex ownership to the next waiter, and yield
+		// our time slice so that the next waiter can start to run immediately.
+		// Note: mutexLocked is not set, the waiter will set it after wakeup.
+		// But mutex is still considered locked if mutexStarving is set,
+		// so new coming goroutines won't acquire it.
+		runtime_Semrelease(&m.sema, true, 1)
+	}
+}
diff --git a/contrib/go/_std_1.19/src/sync/once.go b/contrib/go/_std_1.19/src/sync/once.go
new file mode 100644
index 0000000000..b6399cfc3d
--- /dev/null
+++ b/contrib/go/_std_1.19/src/sync/once.go
@@ -0,0 +1,76 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package sync
+
+import (
+	"sync/atomic"
+)
+
+// Once is an object that will perform exactly one action.
+//
+// A Once must not be copied after first use.
+//
+// In the terminology of the Go memory model,
+// the return from f “synchronizes before”
+// the return from any call of once.Do(f).
+type Once struct {
+	// done indicates whether the action has been performed.
+	// It is first in the struct because it is used in the hot path.
+	// The hot path is inlined at every call site.
+	// Placing done first allows more compact instructions on some architectures (amd64/386),
+	// and fewer instructions (to calculate offset) on other architectures.
+	done uint32
+	m    Mutex
+}
+
+// Do calls the function f if and only if Do is being called for the
+// first time for this instance of Once. In other words, given
+//
+//	var once Once
+//
+// if once.Do(f) is called multiple times, only the first call will invoke f,
+// even if f has a different value in each invocation. A new instance of
+// Once is required for each function to execute.
+//
+// Do is intended for initialization that must be run exactly once. Since f
+// is niladic, it may be necessary to use a function literal to capture the
+// arguments to a function to be invoked by Do:
+//
+//	config.once.Do(func() { config.init(filename) })
+//
+// Because no call to Do returns until the one call to f returns, if f causes
+// Do to be called, it will deadlock.
+//
+// If f panics, Do considers it to have returned; future calls of Do return
+// without calling f.
+func (o *Once) Do(f func()) {
+	// Note: Here is an incorrect implementation of Do:
+	//
+	//	if atomic.CompareAndSwapUint32(&o.done, 0, 1) {
+	//		f()
+	//	}
+	//
+	// Do guarantees that when it returns, f has finished.
+	// This implementation would not implement that guarantee:
+	// given two simultaneous calls, the winner of the cas would
+	// call f, and the second would return immediately, without
+	// waiting for the first's call to f to complete.
+	// This is why the slow path falls back to a mutex, and why
+	// the atomic.StoreUint32 must be delayed until after f returns.
+
+	if atomic.LoadUint32(&o.done) == 0 {
+		// Outlined slow-path to allow inlining of the fast-path.
+		o.doSlow(f)
+	}
+}
+
+func (o *Once) doSlow(f func()) {
+	o.m.Lock()
+	defer o.m.Unlock()
+	if o.done == 0 {
+		defer atomic.StoreUint32(&o.done, 1)
+		f()
+	}
+}
diff --git a/contrib/go/_std_1.19/src/sync/pool.go b/contrib/go/_std_1.19/src/sync/pool.go
new file mode 100644
index 0000000000..cf01e2e189
--- /dev/null
+++ b/contrib/go/_std_1.19/src/sync/pool.go
@@ -0,0 +1,297 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package sync
+
+import (
+	"internal/race"
+	"runtime"
+	"sync/atomic"
+	"unsafe"
+)
+
+// A Pool is a set of temporary objects that may be individually saved and
+// retrieved.
+//
+// Any item stored in the Pool may be removed automatically at any time without
+// notification. If the Pool holds the only reference when this happens, the
+// item might be deallocated.
+//
+// A Pool is safe for use by multiple goroutines simultaneously.
+//
+// Pool's purpose is to cache allocated but unused items for later reuse,
+// relieving pressure on the garbage collector. That is, it makes it easy to
+// build efficient, thread-safe free lists. However, it is not suitable for all
+// free lists.
+//
+// An appropriate use of a Pool is to manage a group of temporary items
+// silently shared among and potentially reused by concurrent independent
+// clients of a package. Pool provides a way to amortize allocation overhead
+// across many clients.
+//
+// An example of good use of a Pool is in the fmt package, which maintains a
+// dynamically-sized store of temporary output buffers. The store scales under
+// load (when many goroutines are actively printing) and shrinks when
+// quiescent.
+//
+// On the other hand, a free list maintained as part of a short-lived object is
+// not a suitable use for a Pool, since the overhead does not amortize well in
+// that scenario. It is more efficient to have such objects implement their own
+// free list.
+//
+// A Pool must not be copied after first use.
+//
+// In the terminology of the Go memory model, a call to Put(x) “synchronizes before”
+// a call to Get returning that same value x.
+// Similarly, a call to New returning x “synchronizes before”
+// a call to Get returning that same value x.
+type Pool struct {
+	noCopy noCopy
+
+	local     unsafe.Pointer // local fixed-size per-P pool, actual type is [P]poolLocal
+	localSize uintptr        // size of the local array
+
+	victim     unsafe.Pointer // local from previous cycle
+	victimSize uintptr        // size of victims array
+
+	// New optionally specifies a function to generate
+	// a value when Get would otherwise return nil.
+	// It may not be changed concurrently with calls to Get.
+	New func() any
+}
+
+// Local per-P Pool appendix.
+type poolLocalInternal struct {
+	private any       // Can be used only by the respective P.
+	shared  poolChain // Local P can pushHead/popHead; any P can popTail.
+}
+
+type poolLocal struct {
+	poolLocalInternal
+
+	// Prevents false sharing on widespread platforms with
+	// 128 mod (cache line size) = 0 .
+	pad [128 - unsafe.Sizeof(poolLocalInternal{})%128]byte
+}
+
+// from runtime
+func fastrandn(n uint32) uint32
+
+var poolRaceHash [128]uint64
+
+// poolRaceAddr returns an address to use as the synchronization point
+// for race detector logic. We don't use the actual pointer stored in x
+// directly, for fear of conflicting with other synchronization on that address.
+// Instead, we hash the pointer to get an index into poolRaceHash.
+// See discussion on golang.org/cl/31589.
+func poolRaceAddr(x any) unsafe.Pointer {
+	ptr := uintptr((*[2]unsafe.Pointer)(unsafe.Pointer(&x))[1])
+	h := uint32((uint64(uint32(ptr)) * 0x85ebca6b) >> 16)
+	return unsafe.Pointer(&poolRaceHash[h%uint32(len(poolRaceHash))])
+}
+
+// Put adds x to the pool.
+func (p *Pool) Put(x any) {
+	if x == nil {
+		return
+	}
+	if race.Enabled {
+		if fastrandn(4) == 0 {
+			// Randomly drop x on floor.
+			return
+		}
+		race.ReleaseMerge(poolRaceAddr(x))
+		race.Disable()
+	}
+	l, _ := p.pin()
+	if l.private == nil {
+		l.private = x
+	} else {
+		l.shared.pushHead(x)
+	}
+	runtime_procUnpin()
+	if race.Enabled {
+		race.Enable()
+	}
+}
+
+// Get selects an arbitrary item from the Pool, removes it from the
+// Pool, and returns it to the caller.
+// Get may choose to ignore the pool and treat it as empty.
+// Callers should not assume any relation between values passed to Put and
+// the values returned by Get.
+//
+// If Get would otherwise return nil and p.New is non-nil, Get returns
+// the result of calling p.New.
+func (p *Pool) Get() any {
+	if race.Enabled {
+		race.Disable()
+	}
+	l, pid := p.pin()
+	x := l.private
+	l.private = nil
+	if x == nil {
+		// Try to pop the head of the local shard. We prefer
+		// the head over the tail for temporal locality of
+		// reuse.
+		x, _ = l.shared.popHead()
+		if x == nil {
+			x = p.getSlow(pid)
+		}
+	}
+	runtime_procUnpin()
+	if race.Enabled {
+		race.Enable()
+		if x != nil {
+			race.Acquire(poolRaceAddr(x))
+		}
+	}
+	if x == nil && p.New != nil {
+		x = p.New()
+	}
+	return x
+}
+
+func (p *Pool) getSlow(pid int) any {
+	// See the comment in pin regarding ordering of the loads.
+	size := runtime_LoadAcquintptr(&p.localSize) // load-acquire
+	locals := p.local                            // load-consume
+	// Try to steal one element from other procs.
+	for i := 0; i < int(size); i++ {
+		l := indexLocal(locals, (pid+i+1)%int(size))
+		if x, _ := l.shared.popTail(); x != nil {
+			return x
+		}
+	}
+
+	// Try the victim cache. We do this after attempting to steal
+	// from all primary caches because we want objects in the
+	// victim cache to age out if at all possible.
+	size = atomic.LoadUintptr(&p.victimSize)
+	if uintptr(pid) >= size {
+		return nil
+	}
+	locals = p.victim
+	l := indexLocal(locals, pid)
+	if x := l.private; x != nil {
+		l.private = nil
+		return x
+	}
+	for i := 0; i < int(size); i++ {
+		l := indexLocal(locals, (pid+i)%int(size))
+		if x, _ := l.shared.popTail(); x != nil {
+			return x
+		}
+	}
+
+	// Mark the victim cache as empty for future gets don't bother
+	// with it.
+	atomic.StoreUintptr(&p.victimSize, 0)
+
+	return nil
+}
+
+// pin pins the current goroutine to P, disables preemption and
+// returns poolLocal pool for the P and the P's id.
+// Caller must call runtime_procUnpin() when done with the pool.
+func (p *Pool) pin() (*poolLocal, int) {
+	pid := runtime_procPin()
+	// In pinSlow we store to local and then to localSize, here we load in opposite order.
+	// Since we've disabled preemption, GC cannot happen in between.
+	// Thus here we must observe local at least as large localSize.
+	// We can observe a newer/larger local, it is fine (we must observe its zero-initialized-ness).
+	s := runtime_LoadAcquintptr(&p.localSize) // load-acquire
+	l := p.local                              // load-consume
+	if uintptr(pid) < s {
+		return indexLocal(l, pid), pid
+	}
+	return p.pinSlow()
+}
+
+func (p *Pool) pinSlow() (*poolLocal, int) {
+	// Retry under the mutex.
+	// Can not lock the mutex while pinned.
+	runtime_procUnpin()
+	allPoolsMu.Lock()
+	defer allPoolsMu.Unlock()
+	pid := runtime_procPin()
+	// poolCleanup won't be called while we are pinned.
+	s := p.localSize
+	l := p.local
+	if uintptr(pid) < s {
+		return indexLocal(l, pid), pid
+	}
+	if p.local == nil {
+		allPools = append(allPools, p)
+	}
+	// If GOMAXPROCS changes between GCs, we re-allocate the array and lose the old one.
+	size := runtime.GOMAXPROCS(0)
+	local := make([]poolLocal, size)
+	atomic.StorePointer(&p.local, unsafe.Pointer(&local[0])) // store-release
+	runtime_StoreReluintptr(&p.localSize, uintptr(size))     // store-release
+	return &local[pid], pid
+}
+
+func poolCleanup() {
+	// This function is called with the world stopped, at the beginning of a garbage collection.
+	// It must not allocate and probably should not call any runtime functions.
+
+	// Because the world is stopped, no pool user can be in a
+	// pinned section (in effect, this has all Ps pinned).
+
+	// Drop victim caches from all pools.
+	for _, p := range oldPools {
+		p.victim = nil
+		p.victimSize = 0
+	}
+
+	// Move primary cache to victim cache.
+	for _, p := range allPools {
+		p.victim = p.local
+		p.victimSize = p.localSize
+		p.local = nil
+		p.localSize = 0
+	}
+
+	// The pools with non-empty primary caches now have non-empty
+	// victim caches and no pools have primary caches.
+	oldPools, allPools = allPools, nil
+}
+
+var (
+	allPoolsMu Mutex
+
+	// allPools is the set of pools that have non-empty primary
+	// caches. Protected by either 1) allPoolsMu and pinning or 2)
+	// STW.
+	allPools []*Pool
+
+	// oldPools is the set of pools that may have non-empty victim
+	// caches. Protected by STW.
+	oldPools []*Pool
+)
+
+func init() {
+	runtime_registerPoolCleanup(poolCleanup)
+}
+
+func indexLocal(l unsafe.Pointer, i int) *poolLocal {
+	lp := unsafe.Pointer(uintptr(l) + uintptr(i)*unsafe.Sizeof(poolLocal{}))
+	return (*poolLocal)(lp)
+}
+
+// Implemented in runtime.
+func runtime_registerPoolCleanup(cleanup func())
+func runtime_procPin() int
+func runtime_procUnpin()
+
+// The below are implemented in runtime/internal/atomic and the
+// compiler also knows to intrinsify the symbol we linkname into this
+// package.
+
+//go:linkname runtime_LoadAcquintptr runtime/internal/atomic.LoadAcquintptr
+func runtime_LoadAcquintptr(ptr *uintptr) uintptr
+
+//go:linkname runtime_StoreReluintptr runtime/internal/atomic.StoreReluintptr
+func runtime_StoreReluintptr(ptr *uintptr, val uintptr) uintptr
diff --git a/contrib/go/_std_1.18/src/sync/poolqueue.go b/contrib/go/_std_1.19/src/sync/poolqueue.go
index 631f2c15fd..631f2c15fd 100644
--- a/contrib/go/_std_1.18/src/sync/poolqueue.go
+++ b/contrib/go/_std_1.19/src/sync/poolqueue.go
diff --git a/contrib/go/_std_1.18/src/sync/runtime.go b/contrib/go/_std_1.19/src/sync/runtime.go
index de2b0a3ccd..de2b0a3ccd 100644
--- a/contrib/go/_std_1.18/src/sync/runtime.go
+++ b/contrib/go/_std_1.19/src/sync/runtime.go
diff --git a/contrib/go/_std_1.18/src/sync/runtime2.go b/contrib/go/_std_1.19/src/sync/runtime2.go
index 9b7e9922fb..9b7e9922fb 100644
--- a/contrib/go/_std_1.18/src/sync/runtime2.go
+++ b/contrib/go/_std_1.19/src/sync/runtime2.go
diff --git a/contrib/go/_std_1.19/src/sync/rwmutex.go b/contrib/go/_std_1.19/src/sync/rwmutex.go
new file mode 100644
index 0000000000..e914f3eba0
--- /dev/null
+++ b/contrib/go/_std_1.19/src/sync/rwmutex.go
@@ -0,0 +1,231 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package sync
+
+import (
+	"internal/race"
+	"sync/atomic"
+	"unsafe"
+)
+
+// There is a modified copy of this file in runtime/rwmutex.go.
+// If you make any changes here, see if you should make them there.
+
+// A RWMutex is a reader/writer mutual exclusion lock.
+// The lock can be held by an arbitrary number of readers or a single writer.
+// The zero value for a RWMutex is an unlocked mutex.
+//
+// A RWMutex must not be copied after first use.
+//
+// If a goroutine holds a RWMutex for reading and another goroutine might
+// call Lock, no goroutine should expect to be able to acquire a read lock
+// until the initial read lock is released. In particular, this prohibits
+// recursive read locking. This is to ensure that the lock eventually becomes
+// available; a blocked Lock call excludes new readers from acquiring the
+// lock.
+//
+// In the terminology of the Go memory model,
+// the n'th call to Unlock “synchronizes before” the m'th call to Lock
+// for any n < m, just as for Mutex.
+// For any call to RLock, there exists an n such that
+// the n'th call to Unlock “synchronizes before” that call to RLock,
+// and the corresponding call to RUnlock “synchronizes before”
+// the n+1'th call to Lock.
+type RWMutex struct {
+	w           Mutex  // held if there are pending writers
+	writerSem   uint32 // semaphore for writers to wait for completing readers
+	readerSem   uint32 // semaphore for readers to wait for completing writers
+	readerCount int32  // number of pending readers
+	readerWait  int32  // number of departing readers
+}
+
+const rwmutexMaxReaders = 1 << 30
+
+// Happens-before relationships are indicated to the race detector via:
+// - Unlock  -> Lock:  readerSem
+// - Unlock  -> RLock: readerSem
+// - RUnlock -> Lock:  writerSem
+//
+// The methods below temporarily disable handling of race synchronization
+// events in order to provide the more precise model above to the race
+// detector.
+//
+// For example, atomic.AddInt32 in RLock should not appear to provide
+// acquire-release semantics, which would incorrectly synchronize racing
+// readers, thus potentially missing races.
+
+// RLock locks rw for reading.
+//
+// It should not be used for recursive read locking; a blocked Lock
+// call excludes new readers from acquiring the lock. See the
+// documentation on the RWMutex type.
+func (rw *RWMutex) RLock() {
+	if race.Enabled {
+		_ = rw.w.state
+		race.Disable()
+	}
+	if atomic.AddInt32(&rw.readerCount, 1) < 0 {
+		// A writer is pending, wait for it.
+		runtime_SemacquireMutex(&rw.readerSem, false, 0)
+	}
+	if race.Enabled {
+		race.Enable()
+		race.Acquire(unsafe.Pointer(&rw.readerSem))
+	}
+}
+
+// TryRLock tries to lock rw for reading and reports whether it succeeded.
+//
+// Note that while correct uses of TryRLock do exist, they are rare,
+// and use of TryRLock is often a sign of a deeper problem
+// in a particular use of mutexes.
+func (rw *RWMutex) TryRLock() bool {
+	if race.Enabled {
+		_ = rw.w.state
+		race.Disable()
+	}
+	for {
+		c := atomic.LoadInt32(&rw.readerCount)
+		if c < 0 {
+			if race.Enabled {
+				race.Enable()
+			}
+			return false
+		}
+		if atomic.CompareAndSwapInt32(&rw.readerCount, c, c+1) {
+			if race.Enabled {
+				race.Enable()
+				race.Acquire(unsafe.Pointer(&rw.readerSem))
+			}
+			return true
+		}
+	}
+}
+
+// RUnlock undoes a single RLock call;
+// it does not affect other simultaneous readers.
+// It is a run-time error if rw is not locked for reading
+// on entry to RUnlock.
+func (rw *RWMutex) RUnlock() {
+	if race.Enabled {
+		_ = rw.w.state
+		race.ReleaseMerge(unsafe.Pointer(&rw.writerSem))
+		race.Disable()
+	}
+	if r := atomic.AddInt32(&rw.readerCount, -1); r < 0 {
+		// Outlined slow-path to allow the fast-path to be inlined
+		rw.rUnlockSlow(r)
+	}
+	if race.Enabled {
+		race.Enable()
+	}
+}
+
+func (rw *RWMutex) rUnlockSlow(r int32) {
+	if r+1 == 0 || r+1 == -rwmutexMaxReaders {
+		race.Enable()
+		fatal("sync: RUnlock of unlocked RWMutex")
+	}
+	// A writer is pending.
+	if atomic.AddInt32(&rw.readerWait, -1) == 0 {
+		// The last reader unblocks the writer.
+		runtime_Semrelease(&rw.writerSem, false, 1)
+	}
+}
+
+// Lock locks rw for writing.
+// If the lock is already locked for reading or writing,
+// Lock blocks until the lock is available.
+func (rw *RWMutex) Lock() {
+	if race.Enabled {
+		_ = rw.w.state
+		race.Disable()
+	}
+	// First, resolve competition with other writers.
+	rw.w.Lock()
+	// Announce to readers there is a pending writer.
+	r := atomic.AddInt32(&rw.readerCount, -rwmutexMaxReaders) + rwmutexMaxReaders
+	// Wait for active readers.
+	if r != 0 && atomic.AddInt32(&rw.readerWait, r) != 0 {
+		runtime_SemacquireMutex(&rw.writerSem, false, 0)
+	}
+	if race.Enabled {
+		race.Enable()
+		race.Acquire(unsafe.Pointer(&rw.readerSem))
+		race.Acquire(unsafe.Pointer(&rw.writerSem))
+	}
+}
+
+// TryLock tries to lock rw for writing and reports whether it succeeded.
+//
+// Note that while correct uses of TryLock do exist, they are rare,
+// and use of TryLock is often a sign of a deeper problem
+// in a particular use of mutexes.
+func (rw *RWMutex) TryLock() bool {
+	if race.Enabled {
+		_ = rw.w.state
+		race.Disable()
+	}
+	if !rw.w.TryLock() {
+		if race.Enabled {
+			race.Enable()
+		}
+		return false
+	}
+	if !atomic.CompareAndSwapInt32(&rw.readerCount, 0, -rwmutexMaxReaders) {
+		rw.w.Unlock()
+		if race.Enabled {
+			race.Enable()
+		}
+		return false
+	}
+	if race.Enabled {
+		race.Enable()
+		race.Acquire(unsafe.Pointer(&rw.readerSem))
+		race.Acquire(unsafe.Pointer(&rw.writerSem))
+	}
+	return true
+}
+
+// Unlock unlocks rw for writing. It is a run-time error if rw is
+// not locked for writing on entry to Unlock.
+//
+// As with Mutexes, a locked RWMutex is not associated with a particular
+// goroutine. One goroutine may RLock (Lock) a RWMutex and then
+// arrange for another goroutine to RUnlock (Unlock) it.
+func (rw *RWMutex) Unlock() {
+	if race.Enabled {
+		_ = rw.w.state
+		race.Release(unsafe.Pointer(&rw.readerSem))
+		race.Disable()
+	}
+
+	// Announce to readers there is no active writer.
+	r := atomic.AddInt32(&rw.readerCount, rwmutexMaxReaders)
+	if r >= rwmutexMaxReaders {
+		race.Enable()
+		fatal("sync: Unlock of unlocked RWMutex")
+	}
+	// Unblock blocked readers, if any.
+	for i := 0; i < int(r); i++ {
+		runtime_Semrelease(&rw.readerSem, false, 0)
+	}
+	// Allow other writers to proceed.
+	rw.w.Unlock()
+	if race.Enabled {
+		race.Enable()
+	}
+}
+
+// RLocker returns a Locker interface that implements
+// the Lock and Unlock methods by calling rw.RLock and rw.RUnlock.
+func (rw *RWMutex) RLocker() Locker {
+	return (*rlocker)(rw)
+}
+
+type rlocker RWMutex
+
+func (r *rlocker) Lock()   { (*RWMutex)(r).RLock() }
+func (r *rlocker) Unlock() { (*RWMutex)(r).RUnlock() }
diff --git a/contrib/go/_std_1.19/src/sync/waitgroup.go b/contrib/go/_std_1.19/src/sync/waitgroup.go
new file mode 100644
index 0000000000..9f26ae106c
--- /dev/null
+++ b/contrib/go/_std_1.19/src/sync/waitgroup.go
@@ -0,0 +1,150 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package sync
+
+import (
+	"internal/race"
+	"sync/atomic"
+	"unsafe"
+)
+
+// A WaitGroup waits for a collection of goroutines to finish.
+// The main goroutine calls Add to set the number of
+// goroutines to wait for. Then each of the goroutines
+// runs and calls Done when finished. At the same time,
+// Wait can be used to block until all goroutines have finished.
+//
+// A WaitGroup must not be copied after first use.
+//
+// In the terminology of the Go memory model, a call to Done
+// “synchronizes before” the return of any Wait call that it unblocks.
+type WaitGroup struct {
+	noCopy noCopy
+
+	// 64-bit value: high 32 bits are counter, low 32 bits are waiter count.
+	// 64-bit atomic operations require 64-bit alignment, but 32-bit
+	// compilers only guarantee that 64-bit fields are 32-bit aligned.
+	// For this reason on 32 bit architectures we need to check in state()
+	// if state1 is aligned or not, and dynamically "swap" the field order if
+	// needed.
+	state1 uint64
+	state2 uint32
+}
+
+// state returns pointers to the state and sema fields stored within wg.state*.
+func (wg *WaitGroup) state() (statep *uint64, semap *uint32) {
+	if unsafe.Alignof(wg.state1) == 8 || uintptr(unsafe.Pointer(&wg.state1))%8 == 0 {
+		// state1 is 64-bit aligned: nothing to do.
+		return &wg.state1, &wg.state2
+	} else {
+		// state1 is 32-bit aligned but not 64-bit aligned: this means that
+		// (&state1)+4 is 64-bit aligned.
+		state := (*[3]uint32)(unsafe.Pointer(&wg.state1))
+		return (*uint64)(unsafe.Pointer(&state[1])), &state[0]
+	}
+}
+
+// Add adds delta, which may be negative, to the WaitGroup counter.
+// If the counter becomes zero, all goroutines blocked on Wait are released.
+// If the counter goes negative, Add panics.
+//
+// Note that calls with a positive delta that occur when the counter is zero
+// must happen before a Wait. Calls with a negative delta, or calls with a
+// positive delta that start when the counter is greater than zero, may happen
+// at any time.
+// Typically this means the calls to Add should execute before the statement
+// creating the goroutine or other event to be waited for.
+// If a WaitGroup is reused to wait for several independent sets of events,
+// new Add calls must happen after all previous Wait calls have returned.
+// See the WaitGroup example.
+func (wg *WaitGroup) Add(delta int) {
+	statep, semap := wg.state()
+	if race.Enabled {
+		_ = *statep // trigger nil deref early
+		if delta < 0 {
+			// Synchronize decrements with Wait.
+			race.ReleaseMerge(unsafe.Pointer(wg))
+		}
+		race.Disable()
+		defer race.Enable()
+	}
+	state := atomic.AddUint64(statep, uint64(delta)<<32)
+	v := int32(state >> 32)
+	w := uint32(state)
+	if race.Enabled && delta > 0 && v == int32(delta) {
+		// The first increment must be synchronized with Wait.
+		// Need to model this as a read, because there can be
+		// several concurrent wg.counter transitions from 0.
+		race.Read(unsafe.Pointer(semap))
+	}
+	if v < 0 {
+		panic("sync: negative WaitGroup counter")
+	}
+	if w != 0 && delta > 0 && v == int32(delta) {
+		panic("sync: WaitGroup misuse: Add called concurrently with Wait")
+	}
+	if v > 0 || w == 0 {
+		return
+	}
+	// This goroutine has set counter to 0 when waiters > 0.
+	// Now there can't be concurrent mutations of state:
+	// - Adds must not happen concurrently with Wait,
+	// - Wait does not increment waiters if it sees counter == 0.
+	// Still do a cheap sanity check to detect WaitGroup misuse.
+	if *statep != state {
+		panic("sync: WaitGroup misuse: Add called concurrently with Wait")
+	}
+	// Reset waiters count to 0.
+	*statep = 0
+	for ; w != 0; w-- {
+		runtime_Semrelease(semap, false, 0)
+	}
+}
+
+// Done decrements the WaitGroup counter by one.
+func (wg *WaitGroup) Done() {
+	wg.Add(-1)
+}
+
+// Wait blocks until the WaitGroup counter is zero.
+func (wg *WaitGroup) Wait() {
+	statep, semap := wg.state()
+	if race.Enabled {
+		_ = *statep // trigger nil deref early
+		race.Disable()
+	}
+	for {
+		state := atomic.LoadUint64(statep)
+		v := int32(state >> 32)
+		w := uint32(state)
+		if v == 0 {
+			// Counter is 0, no need to wait.
+			if race.Enabled {
+				race.Enable()
+				race.Acquire(unsafe.Pointer(wg))
+			}
+			return
+		}
+		// Increment waiters count.
+		if atomic.CompareAndSwapUint64(statep, state, state+1) {
+			if race.Enabled && w == 0 {
+				// Wait must be synchronized with the first Add.
+				// Need to model this is as a write to race with the read in Add.
+				// As a consequence, can do the write only for the first waiter,
+				// otherwise concurrent Waits will race with each other.
+				race.Write(unsafe.Pointer(semap))
+			}
+			runtime_Semacquire(semap)
+			if *statep != 0 {
+				panic("sync: WaitGroup is reused before previous Wait has returned")
+			}
+			if race.Enabled {
+				race.Enable()
+				race.Acquire(unsafe.Pointer(wg))
+			}
+			return
+		}
+	}
+}
diff --git a/contrib/go/_std_1.18/src/syscall/asan0.go b/contrib/go/_std_1.19/src/syscall/asan0.go
index 08bc44dea1..08bc44dea1 100644
--- a/contrib/go/_std_1.18/src/syscall/asan0.go
+++ b/contrib/go/_std_1.19/src/syscall/asan0.go
diff --git a/contrib/go/_std_1.19/src/syscall/asm_darwin_amd64.s b/contrib/go/_std_1.19/src/syscall/asm_darwin_amd64.s
new file mode 100644
index 0000000000..77b58e051b
--- /dev/null
+++ b/contrib/go/_std_1.19/src/syscall/asm_darwin_amd64.s
@@ -0,0 +1,134 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+#include "funcdata.h"
+
+//
+// System call support for AMD64, Darwin
+//
+
+// Trap # in AX, args in DI SI DX, return in AX DX
+
+// func Syscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno);
+TEXT	·Syscall(SB),NOSPLIT,$0-56
+	CALL	runtime·entersyscall<ABIInternal>(SB)
+	MOVQ	a1+8(FP), DI
+	MOVQ	a2+16(FP), SI
+	MOVQ	a3+24(FP), DX
+	MOVQ	trap+0(FP), AX	// syscall entry
+	ADDQ	$0x2000000, AX
+	SYSCALL
+	JCC	ok
+	MOVQ	$-1, r1+32(FP)
+	MOVQ	$0, r2+40(FP)
+	MOVQ	AX, err+48(FP)
+	CALL	runtime·exitsyscall<ABIInternal>(SB)
+	RET
+ok:
+	MOVQ	AX, r1+32(FP)
+	MOVQ	DX, r2+40(FP)
+	MOVQ	$0, err+48(FP)
+	CALL	runtime·exitsyscall<ABIInternal>(SB)
+	RET
+
+// func Syscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno);
+TEXT	·Syscall6(SB),NOSPLIT,$0-80
+	CALL	runtime·entersyscall<ABIInternal>(SB)
+	MOVQ	a1+8(FP), DI
+	MOVQ	a2+16(FP), SI
+	MOVQ	a3+24(FP), DX
+	MOVQ	a4+32(FP), R10
+	MOVQ	a5+40(FP), R8
+	MOVQ	a6+48(FP), R9
+	MOVQ	trap+0(FP), AX	// syscall entry
+	ADDQ	$0x2000000, AX
+	SYSCALL
+	JCC	ok6
+	MOVQ	$-1, r1+56(FP)
+	MOVQ	$0, r2+64(FP)
+	MOVQ	AX, err+72(FP)
+	CALL	runtime·exitsyscall<ABIInternal>(SB)
+	RET
+ok6:
+	MOVQ	AX, r1+56(FP)
+	MOVQ	DX, r2+64(FP)
+	MOVQ	$0, err+72(FP)
+	CALL	runtime·exitsyscall<ABIInternal>(SB)
+	RET
+
+// func Syscall9(trap, a1, a2, a3, a4, a5, a6, a7, a8, a9 uintptr) (r1, r2 uintptr, err Errno)
+TEXT	·Syscall9(SB),NOSPLIT,$0-104
+	CALL	runtime·entersyscall<ABIInternal>(SB)
+	MOVQ	trap+0(FP), AX	// syscall entry
+	MOVQ	a1+8(FP), DI
+	MOVQ	a2+16(FP), SI
+	MOVQ	a3+24(FP), DX
+	MOVQ	a4+32(FP), R10
+	MOVQ	a5+40(FP), R8
+	MOVQ	a6+48(FP), R9
+	MOVQ	a7+56(FP), R11
+	MOVQ	a8+64(FP), R12
+	MOVQ	a9+72(FP), R13
+	SUBQ	$32, SP
+	MOVQ	R11, 8(SP)
+	MOVQ	R12, 16(SP)
+	MOVQ	R13, 24(SP)
+	ADDQ	$0x2000000, AX
+	SYSCALL
+	JCC	ok9
+	ADDQ	$32, SP
+	MOVQ	$-1, r1+80(FP)
+	MOVQ	$0, r2+88(FP)
+	MOVQ	AX, err+96(FP)
+	CALL	runtime·exitsyscall<ABIInternal>(SB)
+	RET
+ok9:
+	ADDQ	$32, SP
+	MOVQ	AX, r1+80(FP)
+	MOVQ	DX, r2+88(FP)
+	MOVQ	$0, err+96(FP)
+	CALL	runtime·exitsyscall<ABIInternal>(SB)
+	RET
+
+// func RawSyscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno)
+TEXT ·RawSyscall(SB),NOSPLIT,$0-56
+	MOVQ	a1+8(FP), DI
+	MOVQ	a2+16(FP), SI
+	MOVQ	a3+24(FP), DX
+	MOVQ	trap+0(FP), AX	// syscall entry
+	ADDQ	$0x2000000, AX
+	SYSCALL
+	JCC	ok1
+	MOVQ	$-1, r1+32(FP)
+	MOVQ	$0, r2+40(FP)
+	MOVQ	AX, err+48(FP)
+	RET
+ok1:
+	MOVQ	AX, r1+32(FP)
+	MOVQ	DX, r2+40(FP)
+	MOVQ	$0, err+48(FP)
+	RET
+
+// func RawSyscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno)
+TEXT	·RawSyscall6(SB),NOSPLIT,$0-80
+	MOVQ	a1+8(FP), DI
+	MOVQ	a2+16(FP), SI
+	MOVQ	a3+24(FP), DX
+	MOVQ	a4+32(FP), R10
+	MOVQ	a5+40(FP), R8
+	MOVQ	a6+48(FP), R9
+	MOVQ	trap+0(FP), AX	// syscall entry
+	ADDQ	$0x2000000, AX
+	SYSCALL
+	JCC	ok2
+	MOVQ	$-1, r1+56(FP)
+	MOVQ	$0, r2+64(FP)
+	MOVQ	AX, err+72(FP)
+	RET
+ok2:
+	MOVQ	AX, r1+56(FP)
+	MOVQ	DX, r2+64(FP)
+	MOVQ	$0, err+72(FP)
+	RET
diff --git a/contrib/go/_std_1.19/src/syscall/asm_linux_amd64.s b/contrib/go/_std_1.19/src/syscall/asm_linux_amd64.s
new file mode 100644
index 0000000000..3206a45d5d
--- /dev/null
+++ b/contrib/go/_std_1.19/src/syscall/asm_linux_amd64.s
@@ -0,0 +1,68 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+#include "funcdata.h"
+
+//
+// System calls for AMD64, Linux
+//
+
+#define SYS_gettimeofday 96
+
+// func rawVforkSyscall(trap, a1 uintptr) (r1, err uintptr)
+TEXT ·rawVforkSyscall(SB),NOSPLIT|NOFRAME,$0-32
+	MOVQ	a1+8(FP), DI
+	MOVQ	$0, SI
+	MOVQ	$0, DX
+	MOVQ	$0, R10
+	MOVQ	$0, R8
+	MOVQ	$0, R9
+	MOVQ	trap+0(FP), AX	// syscall entry
+	POPQ	R12 // preserve return address
+	SYSCALL
+	PUSHQ	R12
+	CMPQ	AX, $0xfffffffffffff001
+	JLS	ok2
+	MOVQ	$-1, r1+16(FP)
+	NEGQ	AX
+	MOVQ	AX, err+24(FP)
+	RET
+ok2:
+	MOVQ	AX, r1+16(FP)
+	MOVQ	$0, err+24(FP)
+	RET
+
+// func rawSyscallNoError(trap, a1, a2, a3 uintptr) (r1, r2 uintptr)
+TEXT ·rawSyscallNoError(SB),NOSPLIT,$0-48
+	MOVQ	a1+8(FP), DI
+	MOVQ	a2+16(FP), SI
+	MOVQ	a3+24(FP), DX
+	MOVQ	trap+0(FP), AX	// syscall entry
+	SYSCALL
+	MOVQ	AX, r1+32(FP)
+	MOVQ	DX, r2+40(FP)
+	RET
+
+// func gettimeofday(tv *Timeval) (err uintptr)
+TEXT ·gettimeofday(SB),NOSPLIT,$0-16
+	MOVQ	tv+0(FP), DI
+	MOVQ	$0, SI
+	MOVQ	runtime·vdsoGettimeofdaySym(SB), AX
+	TESTQ   AX, AX
+	JZ fallback
+	CALL	AX
+ret:
+	CMPQ	AX, $0xfffffffffffff001
+	JLS	ok7
+	NEGQ	AX
+	MOVQ	AX, err+8(FP)
+	RET
+fallback:
+	MOVL	$SYS_gettimeofday, AX
+	SYSCALL
+	JMP ret
+ok7:
+	MOVQ	$0, err+8(FP)
+	RET
diff --git a/contrib/go/_std_1.18/src/syscall/bpf_darwin.go b/contrib/go/_std_1.19/src/syscall/bpf_darwin.go
index fb86049ae9..fb86049ae9 100644
--- a/contrib/go/_std_1.18/src/syscall/bpf_darwin.go
+++ b/contrib/go/_std_1.19/src/syscall/bpf_darwin.go
diff --git a/contrib/go/_std_1.19/src/syscall/dirent.go b/contrib/go/_std_1.19/src/syscall/dirent.go
new file mode 100644
index 0000000000..b10608a662
--- /dev/null
+++ b/contrib/go/_std_1.19/src/syscall/dirent.go
@@ -0,0 +1,102 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm)
+
+package syscall
+
+import "unsafe"
+
+// readInt returns the size-bytes unsigned integer in native byte order at offset off.
+func readInt(b []byte, off, size uintptr) (u uint64, ok bool) {
+	if len(b) < int(off+size) {
+		return 0, false
+	}
+	if isBigEndian {
+		return readIntBE(b[off:], size), true
+	}
+	return readIntLE(b[off:], size), true
+}
+
+func readIntBE(b []byte, size uintptr) uint64 {
+	switch size {
+	case 1:
+		return uint64(b[0])
+	case 2:
+		_ = b[1] // bounds check hint to compiler; see golang.org/issue/14808
+		return uint64(b[1]) | uint64(b[0])<<8
+	case 4:
+		_ = b[3] // bounds check hint to compiler; see golang.org/issue/14808
+		return uint64(b[3]) | uint64(b[2])<<8 | uint64(b[1])<<16 | uint64(b[0])<<24
+	case 8:
+		_ = b[7] // bounds check hint to compiler; see golang.org/issue/14808
+		return uint64(b[7]) | uint64(b[6])<<8 | uint64(b[5])<<16 | uint64(b[4])<<24 |
+			uint64(b[3])<<32 | uint64(b[2])<<40 | uint64(b[1])<<48 | uint64(b[0])<<56
+	default:
+		panic("syscall: readInt with unsupported size")
+	}
+}
+
+func readIntLE(b []byte, size uintptr) uint64 {
+	switch size {
+	case 1:
+		return uint64(b[0])
+	case 2:
+		_ = b[1] // bounds check hint to compiler; see golang.org/issue/14808
+		return uint64(b[0]) | uint64(b[1])<<8
+	case 4:
+		_ = b[3] // bounds check hint to compiler; see golang.org/issue/14808
+		return uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24
+	case 8:
+		_ = b[7] // bounds check hint to compiler; see golang.org/issue/14808
+		return uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 |
+			uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56
+	default:
+		panic("syscall: readInt with unsupported size")
+	}
+}
+
+// ParseDirent parses up to max directory entries in buf,
+// appending the names to names. It returns the number of
+// bytes consumed from buf, the number of entries added
+// to names, and the new names slice.
+func ParseDirent(buf []byte, max int, names []string) (consumed int, count int, newnames []string) {
+	origlen := len(buf)
+	count = 0
+	for max != 0 && len(buf) > 0 {
+		reclen, ok := direntReclen(buf)
+		if !ok || reclen > uint64(len(buf)) {
+			return origlen, count, names
+		}
+		rec := buf[:reclen]
+		buf = buf[reclen:]
+		ino, ok := direntIno(rec)
+		if !ok {
+			break
+		}
+		if ino == 0 { // File absent in directory.
+			continue
+		}
+		const namoff = uint64(unsafe.Offsetof(Dirent{}.Name))
+		namlen, ok := direntNamlen(rec)
+		if !ok || namoff+namlen > uint64(len(rec)) {
+			break
+		}
+		name := rec[namoff : namoff+namlen]
+		for i, c := range name {
+			if c == 0 {
+				name = name[:i]
+				break
+			}
+		}
+		// Check for useless names before allocating a string.
+		if string(name) == "." || string(name) == ".." {
+			continue
+		}
+		max--
+		count++
+		names = append(names, string(name))
+	}
+	return origlen - len(buf), count, names
+}
diff --git a/contrib/go/_std_1.19/src/syscall/endian_little.go b/contrib/go/_std_1.19/src/syscall/endian_little.go
new file mode 100644
index 0000000000..f5fcb58db4
--- /dev/null
+++ b/contrib/go/_std_1.19/src/syscall/endian_little.go
@@ -0,0 +1,9 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+//
+//go:build 386 || amd64 || arm || arm64 || loong64 || ppc64le || mips64le || mipsle || riscv64 || wasm
+
+package syscall
+
+const isBigEndian = false
diff --git a/contrib/go/_std_1.19/src/syscall/env_unix.go b/contrib/go/_std_1.19/src/syscall/env_unix.go
new file mode 100644
index 0000000000..67e6c5fbe2
--- /dev/null
+++ b/contrib/go/_std_1.19/src/syscall/env_unix.go
@@ -0,0 +1,155 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm) || plan9
+
+// Unix environment variables.
+
+package syscall
+
+import (
+	"runtime"
+	"sync"
+)
+
+var (
+	// envOnce guards initialization by copyenv, which populates env.
+	envOnce sync.Once
+
+	// envLock guards env and envs.
+	envLock sync.RWMutex
+
+	// env maps from an environment variable to its first occurrence in envs.
+	env map[string]int
+
+	// envs is provided by the runtime. elements are expected to
+	// be of the form "key=value". An empty string means deleted
+	// (or a duplicate to be ignored).
+	envs []string = runtime_envs()
+)
+
+func runtime_envs() []string // in package runtime
+
+// setenv_c and unsetenv_c are provided by the runtime but are no-ops
+// if cgo isn't loaded.
+func setenv_c(k, v string)
+func unsetenv_c(k string)
+
+func copyenv() {
+	env = make(map[string]int)
+	for i, s := range envs {
+		for j := 0; j < len(s); j++ {
+			if s[j] == '=' {
+				key := s[:j]
+				if _, ok := env[key]; !ok {
+					env[key] = i // first mention of key
+				} else {
+					// Clear duplicate keys. This permits Unsetenv to
+					// safely delete only the first item without
+					// worrying about unshadowing a later one,
+					// which might be a security problem.
+					envs[i] = ""
+				}
+				break
+			}
+		}
+	}
+}
+
+func Unsetenv(key string) error {
+	envOnce.Do(copyenv)
+
+	envLock.Lock()
+	defer envLock.Unlock()
+
+	if i, ok := env[key]; ok {
+		envs[i] = ""
+		delete(env, key)
+	}
+	unsetenv_c(key)
+	return nil
+}
+
+func Getenv(key string) (value string, found bool) {
+	envOnce.Do(copyenv)
+	if len(key) == 0 {
+		return "", false
+	}
+
+	envLock.RLock()
+	defer envLock.RUnlock()
+
+	i, ok := env[key]
+	if !ok {
+		return "", false
+	}
+	s := envs[i]
+	for i := 0; i < len(s); i++ {
+		if s[i] == '=' {
+			return s[i+1:], true
+		}
+	}
+	return "", false
+}
+
+func Setenv(key, value string) error {
+	envOnce.Do(copyenv)
+	if len(key) == 0 {
+		return EINVAL
+	}
+	for i := 0; i < len(key); i++ {
+		if key[i] == '=' || key[i] == 0 {
+			return EINVAL
+		}
+	}
+	// On Plan 9, null is used as a separator, eg in $path.
+	if runtime.GOOS != "plan9" {
+		for i := 0; i < len(value); i++ {
+			if value[i] == 0 {
+				return EINVAL
+			}
+		}
+	}
+
+	envLock.Lock()
+	defer envLock.Unlock()
+
+	i, ok := env[key]
+	kv := key + "=" + value
+	if ok {
+		envs[i] = kv
+	} else {
+		i = len(envs)
+		envs = append(envs, kv)
+	}
+	env[key] = i
+	setenv_c(key, value)
+	return nil
+}
+
+func Clearenv() {
+	envOnce.Do(copyenv) // prevent copyenv in Getenv/Setenv
+
+	envLock.Lock()
+	defer envLock.Unlock()
+
+	for k := range env {
+		unsetenv_c(k)
+	}
+	env = make(map[string]int)
+	envs = []string{}
+}
+
+func Environ() []string {
+	envOnce.Do(copyenv)
+	envLock.RLock()
+	defer envLock.RUnlock()
+	a := make([]string, 0, len(envs))
+	for _, env := range envs {
+		if env != "" {
+			a = append(a, env)
+		}
+	}
+	return a
+}
diff --git a/contrib/go/_std_1.19/src/syscall/exec_libc2.go b/contrib/go/_std_1.19/src/syscall/exec_libc2.go
new file mode 100644
index 0000000000..9eb61a5d35
--- /dev/null
+++ b/contrib/go/_std_1.19/src/syscall/exec_libc2.go
@@ -0,0 +1,281 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build darwin || (openbsd && !mips64)
+
+package syscall
+
+import (
+	"internal/abi"
+	"runtime"
+	"unsafe"
+)
+
+type SysProcAttr struct {
+	Chroot     string      // Chroot.
+	Credential *Credential // Credential.
+	Ptrace     bool        // Enable tracing.
+	Setsid     bool        // Create session.
+	// Setpgid sets the process group ID of the child to Pgid,
+	// or, if Pgid == 0, to the new child's process ID.
+	Setpgid bool
+	// Setctty sets the controlling terminal of the child to
+	// file descriptor Ctty. Ctty must be a descriptor number
+	// in the child process: an index into ProcAttr.Files.
+	// This is only meaningful if Setsid is true.
+	Setctty bool
+	Noctty  bool // Detach fd 0 from controlling terminal
+	Ctty    int  // Controlling TTY fd
+	// Foreground places the child process group in the foreground.
+	// This implies Setpgid. The Ctty field must be set to
+	// the descriptor of the controlling TTY.
+	// Unlike Setctty, in this case Ctty must be a descriptor
+	// number in the parent process.
+	Foreground bool
+	Pgid       int // Child's process group ID if Setpgid.
+}
+
+// Implemented in runtime package.
+func runtime_BeforeFork()
+func runtime_AfterFork()
+func runtime_AfterForkInChild()
+
+// Fork, dup fd onto 0..len(fd), and exec(argv0, argvv, envv) in child.
+// If a dup or exec fails, write the errno error to pipe.
+// (Pipe is close-on-exec so if exec succeeds, it will be closed.)
+// In the child, this function must not acquire any locks, because
+// they might have been locked at the time of the fork. This means
+// no rescheduling, no malloc calls, and no new stack segments.
+// For the same reason compiler does not race instrument it.
+// The calls to rawSyscall are okay because they are assembly
+// functions that do not grow the stack.
+//
+//go:norace
+func forkAndExecInChild(argv0 *byte, argv, envv []*byte, chroot, dir *byte, attr *ProcAttr, sys *SysProcAttr, pipe int) (pid int, err Errno) {
+	// Declare all variables at top in case any
+	// declarations require heap allocation (e.g., err1).
+	var (
+		r1     uintptr
+		err1   Errno
+		nextfd int
+		i      int
+	)
+
+	// guard against side effects of shuffling fds below.
+	// Make sure that nextfd is beyond any currently open files so
+	// that we can't run the risk of overwriting any of them.
+	fd := make([]int, len(attr.Files))
+	nextfd = len(attr.Files)
+	for i, ufd := range attr.Files {
+		if nextfd < int(ufd) {
+			nextfd = int(ufd)
+		}
+		fd[i] = int(ufd)
+	}
+	nextfd++
+
+	// About to call fork.
+	// No more allocation or calls of non-assembly functions.
+	runtime_BeforeFork()
+	r1, _, err1 = rawSyscall(abi.FuncPCABI0(libc_fork_trampoline), 0, 0, 0)
+	if err1 != 0 {
+		runtime_AfterFork()
+		return 0, err1
+	}
+
+	if r1 != 0 {
+		// parent; return PID
+		runtime_AfterFork()
+		return int(r1), 0
+	}
+
+	// Fork succeeded, now in child.
+
+	// Enable tracing if requested.
+	if sys.Ptrace {
+		if err := ptrace(PTRACE_TRACEME, 0, 0, 0); err != nil {
+			err1 = err.(Errno)
+			goto childerror
+		}
+	}
+
+	// Session ID
+	if sys.Setsid {
+		_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_setsid_trampoline), 0, 0, 0)
+		if err1 != 0 {
+			goto childerror
+		}
+	}
+
+	// Set process group
+	if sys.Setpgid || sys.Foreground {
+		// Place child in process group.
+		_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_setpgid_trampoline), 0, uintptr(sys.Pgid), 0)
+		if err1 != 0 {
+			goto childerror
+		}
+	}
+
+	if sys.Foreground {
+		// This should really be pid_t, however _C_int (aka int32) is
+		// generally equivalent.
+		pgrp := _C_int(sys.Pgid)
+		if pgrp == 0 {
+			r1, _, err1 = rawSyscall(abi.FuncPCABI0(libc_getpid_trampoline), 0, 0, 0)
+			if err1 != 0 {
+				goto childerror
+			}
+			pgrp = _C_int(r1)
+		}
+
+		// Place process group in foreground.
+		_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_ioctl_trampoline), uintptr(sys.Ctty), uintptr(TIOCSPGRP), uintptr(unsafe.Pointer(&pgrp)))
+		if err1 != 0 {
+			goto childerror
+		}
+	}
+
+	// Restore the signal mask. We do this after TIOCSPGRP to avoid
+	// having the kernel send a SIGTTOU signal to the process group.
+	runtime_AfterForkInChild()
+
+	// Chroot
+	if chroot != nil {
+		_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_chroot_trampoline), uintptr(unsafe.Pointer(chroot)), 0, 0)
+		if err1 != 0 {
+			goto childerror
+		}
+	}
+
+	// User and groups
+	if cred := sys.Credential; cred != nil {
+		ngroups := uintptr(len(cred.Groups))
+		groups := uintptr(0)
+		if ngroups > 0 {
+			groups = uintptr(unsafe.Pointer(&cred.Groups[0]))
+		}
+		if !cred.NoSetGroups {
+			_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_setgroups_trampoline), ngroups, groups, 0)
+			if err1 != 0 {
+				goto childerror
+			}
+		}
+		_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_setgid_trampoline), uintptr(cred.Gid), 0, 0)
+		if err1 != 0 {
+			goto childerror
+		}
+		_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_setuid_trampoline), uintptr(cred.Uid), 0, 0)
+		if err1 != 0 {
+			goto childerror
+		}
+	}
+
+	// Chdir
+	if dir != nil {
+		_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_chdir_trampoline), uintptr(unsafe.Pointer(dir)), 0, 0)
+		if err1 != 0 {
+			goto childerror
+		}
+	}
+
+	// Pass 1: look for fd[i] < i and move those up above len(fd)
+	// so that pass 2 won't stomp on an fd it needs later.
+	if pipe < nextfd {
+		if runtime.GOOS == "openbsd" {
+			_, _, err1 = rawSyscall(dupTrampoline, uintptr(pipe), uintptr(nextfd), O_CLOEXEC)
+		} else {
+			_, _, err1 = rawSyscall(dupTrampoline, uintptr(pipe), uintptr(nextfd), 0)
+			if err1 != 0 {
+				goto childerror
+			}
+			_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_fcntl_trampoline), uintptr(nextfd), F_SETFD, FD_CLOEXEC)
+		}
+		if err1 != 0 {
+			goto childerror
+		}
+		pipe = nextfd
+		nextfd++
+	}
+	for i = 0; i < len(fd); i++ {
+		if fd[i] >= 0 && fd[i] < int(i) {
+			if nextfd == pipe { // don't stomp on pipe
+				nextfd++
+			}
+			if runtime.GOOS == "openbsd" {
+				_, _, err1 = rawSyscall(dupTrampoline, uintptr(fd[i]), uintptr(nextfd), O_CLOEXEC)
+			} else {
+				_, _, err1 = rawSyscall(dupTrampoline, uintptr(fd[i]), uintptr(nextfd), 0)
+				if err1 != 0 {
+					goto childerror
+				}
+				_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_fcntl_trampoline), uintptr(nextfd), F_SETFD, FD_CLOEXEC)
+			}
+			if err1 != 0 {
+				goto childerror
+			}
+			fd[i] = nextfd
+			nextfd++
+		}
+	}
+
+	// Pass 2: dup fd[i] down onto i.
+	for i = 0; i < len(fd); i++ {
+		if fd[i] == -1 {
+			rawSyscall(abi.FuncPCABI0(libc_close_trampoline), uintptr(i), 0, 0)
+			continue
+		}
+		if fd[i] == int(i) {
+			// dup2(i, i) won't clear close-on-exec flag on Linux,
+			// probably not elsewhere either.
+			_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_fcntl_trampoline), uintptr(fd[i]), F_SETFD, 0)
+			if err1 != 0 {
+				goto childerror
+			}
+			continue
+		}
+		// The new fd is created NOT close-on-exec,
+		// which is exactly what we want.
+		_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_dup2_trampoline), uintptr(fd[i]), uintptr(i), 0)
+		if err1 != 0 {
+			goto childerror
+		}
+	}
+
+	// By convention, we don't close-on-exec the fds we are
+	// started with, so if len(fd) < 3, close 0, 1, 2 as needed.
+	// Programs that know they inherit fds >= 3 will need
+	// to set them close-on-exec.
+	for i = len(fd); i < 3; i++ {
+		rawSyscall(abi.FuncPCABI0(libc_close_trampoline), uintptr(i), 0, 0)
+	}
+
+	// Detach fd 0 from tty
+	if sys.Noctty {
+		_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_ioctl_trampoline), 0, uintptr(TIOCNOTTY), 0)
+		if err1 != 0 {
+			goto childerror
+		}
+	}
+
+	// Set the controlling TTY to Ctty
+	if sys.Setctty {
+		_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_ioctl_trampoline), uintptr(sys.Ctty), uintptr(TIOCSCTTY), 0)
+		if err1 != 0 {
+			goto childerror
+		}
+	}
+
+	// Time to exec.
+	_, _, err1 = rawSyscall(abi.FuncPCABI0(libc_execve_trampoline),
+		uintptr(unsafe.Pointer(argv0)),
+		uintptr(unsafe.Pointer(&argv[0])),
+		uintptr(unsafe.Pointer(&envv[0])))
+
+childerror:
+	// send error code on pipe
+	rawSyscall(abi.FuncPCABI0(libc_write_trampoline), uintptr(pipe), uintptr(unsafe.Pointer(&err1)), unsafe.Sizeof(err1))
+	for {
+		rawSyscall(abi.FuncPCABI0(libc_exit_trampoline), 253, 0, 0)
+	}
+}
diff --git a/contrib/go/_std_1.19/src/syscall/exec_linux.go b/contrib/go/_std_1.19/src/syscall/exec_linux.go
new file mode 100644
index 0000000000..554aad412d
--- /dev/null
+++ b/contrib/go/_std_1.19/src/syscall/exec_linux.go
@@ -0,0 +1,626 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build linux
+
+package syscall
+
+import (
+	"internal/itoa"
+	"runtime"
+	"unsafe"
+)
+
+// SysProcIDMap holds Container ID to Host ID mappings used for User Namespaces in Linux.
+// See user_namespaces(7).
+type SysProcIDMap struct {
+	ContainerID int // Container ID.
+	HostID      int // Host ID.
+	Size        int // Size.
+}
+
+type SysProcAttr struct {
+	Chroot     string      // Chroot.
+	Credential *Credential // Credential.
+	// Ptrace tells the child to call ptrace(PTRACE_TRACEME).
+	// Call runtime.LockOSThread before starting a process with this set,
+	// and don't call UnlockOSThread until done with PtraceSyscall calls.
+	Ptrace bool
+	Setsid bool // Create session.
+	// Setpgid sets the process group ID of the child to Pgid,
+	// or, if Pgid == 0, to the new child's process ID.
+	Setpgid bool
+	// Setctty sets the controlling terminal of the child to
+	// file descriptor Ctty. Ctty must be a descriptor number
+	// in the child process: an index into ProcAttr.Files.
+	// This is only meaningful if Setsid is true.
+	Setctty bool
+	Noctty  bool // Detach fd 0 from controlling terminal
+	Ctty    int  // Controlling TTY fd
+	// Foreground places the child process group in the foreground.
+	// This implies Setpgid. The Ctty field must be set to
+	// the descriptor of the controlling TTY.
+	// Unlike Setctty, in this case Ctty must be a descriptor
+	// number in the parent process.
+	Foreground bool
+	Pgid       int // Child's process group ID if Setpgid.
+	// Pdeathsig, if non-zero, is a signal that the kernel will send to
+	// the child process when the creating thread dies. Note that the signal
+	// is sent on thread termination, which may happen before process termination.
+	// There are more details at https://go.dev/issue/27505.
+	Pdeathsig    Signal
+	Cloneflags   uintptr        // Flags for clone calls (Linux only)
+	Unshareflags uintptr        // Flags for unshare calls (Linux only)
+	UidMappings  []SysProcIDMap // User ID mappings for user namespaces.
+	GidMappings  []SysProcIDMap // Group ID mappings for user namespaces.
+	// GidMappingsEnableSetgroups enabling setgroups syscall.
+	// If false, then setgroups syscall will be disabled for the child process.
+	// This parameter is no-op if GidMappings == nil. Otherwise for unprivileged
+	// users this should be set to false for mappings work.
+	GidMappingsEnableSetgroups bool
+	AmbientCaps                []uintptr // Ambient capabilities (Linux only)
+}
+
+var (
+	none  = [...]byte{'n', 'o', 'n', 'e', 0}
+	slash = [...]byte{'/', 0}
+)
+
+// Implemented in runtime package.
+func runtime_BeforeFork()
+func runtime_AfterFork()
+func runtime_AfterForkInChild()
+
+// Fork, dup fd onto 0..len(fd), and exec(argv0, argvv, envv) in child.
+// If a dup or exec fails, write the errno error to pipe.
+// (Pipe is close-on-exec so if exec succeeds, it will be closed.)
+// In the child, this function must not acquire any locks, because
+// they might have been locked at the time of the fork. This means
+// no rescheduling, no malloc calls, and no new stack segments.
+// For the same reason compiler does not race instrument it.
+// The calls to RawSyscall are okay because they are assembly
+// functions that do not grow the stack.
+//
+//go:norace
+func forkAndExecInChild(argv0 *byte, argv, envv []*byte, chroot, dir *byte, attr *ProcAttr, sys *SysProcAttr, pipe int) (pid int, err Errno) {
+	// Set up and fork. This returns immediately in the parent or
+	// if there's an error.
+	r1, err1, p, locked := forkAndExecInChild1(argv0, argv, envv, chroot, dir, attr, sys, pipe)
+	if locked {
+		runtime_AfterFork()
+	}
+	if err1 != 0 {
+		return 0, err1
+	}
+
+	// parent; return PID
+	pid = int(r1)
+
+	if sys.UidMappings != nil || sys.GidMappings != nil {
+		Close(p[0])
+		var err2 Errno
+		// uid/gid mappings will be written after fork and unshare(2) for user
+		// namespaces.
+		if sys.Unshareflags&CLONE_NEWUSER == 0 {
+			if err := writeUidGidMappings(pid, sys); err != nil {
+				err2 = err.(Errno)
+			}
+		}
+		RawSyscall(SYS_WRITE, uintptr(p[1]), uintptr(unsafe.Pointer(&err2)), unsafe.Sizeof(err2))
+		Close(p[1])
+	}
+
+	return pid, 0
+}
+
+const _LINUX_CAPABILITY_VERSION_3 = 0x20080522
+
+type capHeader struct {
+	version uint32
+	pid     int32
+}
+
+type capData struct {
+	effective   uint32
+	permitted   uint32
+	inheritable uint32
+}
+type caps struct {
+	hdr  capHeader
+	data [2]capData
+}
+
+// See CAP_TO_INDEX in linux/capability.h:
+func capToIndex(cap uintptr) uintptr { return cap >> 5 }
+
+// See CAP_TO_MASK in linux/capability.h:
+func capToMask(cap uintptr) uint32 { return 1 << uint(cap&31) }
+
+// forkAndExecInChild1 implements the body of forkAndExecInChild up to
+// the parent's post-fork path. This is a separate function so we can
+// separate the child's and parent's stack frames if we're using
+// vfork.
+//
+// This is go:noinline because the point is to keep the stack frames
+// of this and forkAndExecInChild separate.
+//
+//go:noinline
+//go:norace
+func forkAndExecInChild1(argv0 *byte, argv, envv []*byte, chroot, dir *byte, attr *ProcAttr, sys *SysProcAttr, pipe int) (r1 uintptr, err1 Errno, p [2]int, locked bool) {
+	// Defined in linux/prctl.h starting with Linux 4.3.
+	const (
+		PR_CAP_AMBIENT       = 0x2f
+		PR_CAP_AMBIENT_RAISE = 0x2
+	)
+
+	// vfork requires that the child not touch any of the parent's
+	// active stack frames. Hence, the child does all post-fork
+	// processing in this stack frame and never returns, while the
+	// parent returns immediately from this frame and does all
+	// post-fork processing in the outer frame.
+	// Declare all variables at top in case any
+	// declarations require heap allocation (e.g., err1).
+	var (
+		err2                      Errno
+		nextfd                    int
+		i                         int
+		caps                      caps
+		fd1                       uintptr
+		puid, psetgroups, pgid    []byte
+		uidmap, setgroups, gidmap []byte
+	)
+
+	if sys.UidMappings != nil {
+		puid = []byte("/proc/self/uid_map\000")
+		uidmap = formatIDMappings(sys.UidMappings)
+	}
+
+	if sys.GidMappings != nil {
+		psetgroups = []byte("/proc/self/setgroups\000")
+		pgid = []byte("/proc/self/gid_map\000")
+
+		if sys.GidMappingsEnableSetgroups {
+			setgroups = []byte("allow\000")
+		} else {
+			setgroups = []byte("deny\000")
+		}
+		gidmap = formatIDMappings(sys.GidMappings)
+	}
+
+	// Record parent PID so child can test if it has died.
+	ppid, _ := rawSyscallNoError(SYS_GETPID, 0, 0, 0)
+
+	// Guard against side effects of shuffling fds below.
+	// Make sure that nextfd is beyond any currently open files so
+	// that we can't run the risk of overwriting any of them.
+	fd := make([]int, len(attr.Files))
+	nextfd = len(attr.Files)
+	for i, ufd := range attr.Files {
+		if nextfd < int(ufd) {
+			nextfd = int(ufd)
+		}
+		fd[i] = int(ufd)
+	}
+	nextfd++
+
+	// Allocate another pipe for parent to child communication for
+	// synchronizing writing of User ID/Group ID mappings.
+	if sys.UidMappings != nil || sys.GidMappings != nil {
+		if err := forkExecPipe(p[:]); err != nil {
+			err1 = err.(Errno)
+			return
+		}
+	}
+
+	// About to call fork.
+	// No more allocation or calls of non-assembly functions.
+	runtime_BeforeFork()
+	locked = true
+	switch {
+	case sys.Cloneflags&CLONE_NEWUSER == 0 && sys.Unshareflags&CLONE_NEWUSER == 0:
+		r1, err1 = rawVforkSyscall(SYS_CLONE, uintptr(SIGCHLD|CLONE_VFORK|CLONE_VM)|sys.Cloneflags)
+	case runtime.GOARCH == "s390x":
+		r1, _, err1 = RawSyscall6(SYS_CLONE, 0, uintptr(SIGCHLD)|sys.Cloneflags, 0, 0, 0, 0)
+	default:
+		r1, _, err1 = RawSyscall6(SYS_CLONE, uintptr(SIGCHLD)|sys.Cloneflags, 0, 0, 0, 0, 0)
+	}
+	if err1 != 0 || r1 != 0 {
+		// If we're in the parent, we must return immediately
+		// so we're not in the same stack frame as the child.
+		// This can at most use the return PC, which the child
+		// will not modify, and the results of
+		// rawVforkSyscall, which must have been written after
+		// the child was replaced.
+		return
+	}
+
+	// Fork succeeded, now in child.
+
+	// Enable the "keep capabilities" flag to set ambient capabilities later.
+	if len(sys.AmbientCaps) > 0 {
+		_, _, err1 = RawSyscall6(SYS_PRCTL, PR_SET_KEEPCAPS, 1, 0, 0, 0, 0)
+		if err1 != 0 {
+			goto childerror
+		}
+	}
+
+	// Wait for User ID/Group ID mappings to be written.
+	if sys.UidMappings != nil || sys.GidMappings != nil {
+		if _, _, err1 = RawSyscall(SYS_CLOSE, uintptr(p[1]), 0, 0); err1 != 0 {
+			goto childerror
+		}
+		r1, _, err1 = RawSyscall(SYS_READ, uintptr(p[0]), uintptr(unsafe.Pointer(&err2)), unsafe.Sizeof(err2))
+		if err1 != 0 {
+			goto childerror
+		}
+		if r1 != unsafe.Sizeof(err2) {
+			err1 = EINVAL
+			goto childerror
+		}
+		if err2 != 0 {
+			err1 = err2
+			goto childerror
+		}
+	}
+
+	// Session ID
+	if sys.Setsid {
+		_, _, err1 = RawSyscall(SYS_SETSID, 0, 0, 0)
+		if err1 != 0 {
+			goto childerror
+		}
+	}
+
+	// Set process group
+	if sys.Setpgid || sys.Foreground {
+		// Place child in process group.
+		_, _, err1 = RawSyscall(SYS_SETPGID, 0, uintptr(sys.Pgid), 0)
+		if err1 != 0 {
+			goto childerror
+		}
+	}
+
+	if sys.Foreground {
+		pgrp := int32(sys.Pgid)
+		if pgrp == 0 {
+			r1, _ = rawSyscallNoError(SYS_GETPID, 0, 0, 0)
+
+			pgrp = int32(r1)
+		}
+
+		// Place process group in foreground.
+		_, _, err1 = RawSyscall(SYS_IOCTL, uintptr(sys.Ctty), uintptr(TIOCSPGRP), uintptr(unsafe.Pointer(&pgrp)))
+		if err1 != 0 {
+			goto childerror
+		}
+	}
+
+	// Restore the signal mask. We do this after TIOCSPGRP to avoid
+	// having the kernel send a SIGTTOU signal to the process group.
+	runtime_AfterForkInChild()
+
+	// Unshare
+	if sys.Unshareflags != 0 {
+		_, _, err1 = RawSyscall(SYS_UNSHARE, sys.Unshareflags, 0, 0)
+		if err1 != 0 {
+			goto childerror
+		}
+
+		if sys.Unshareflags&CLONE_NEWUSER != 0 && sys.GidMappings != nil {
+			dirfd := int(_AT_FDCWD)
+			if fd1, _, err1 = RawSyscall6(SYS_OPENAT, uintptr(dirfd), uintptr(unsafe.Pointer(&psetgroups[0])), uintptr(O_WRONLY), 0, 0, 0); err1 != 0 {
+				goto childerror
+			}
+			r1, _, err1 = RawSyscall(SYS_WRITE, uintptr(fd1), uintptr(unsafe.Pointer(&setgroups[0])), uintptr(len(setgroups)))
+			if err1 != 0 {
+				goto childerror
+			}
+			if _, _, err1 = RawSyscall(SYS_CLOSE, uintptr(fd1), 0, 0); err1 != 0 {
+				goto childerror
+			}
+
+			if fd1, _, err1 = RawSyscall6(SYS_OPENAT, uintptr(dirfd), uintptr(unsafe.Pointer(&pgid[0])), uintptr(O_WRONLY), 0, 0, 0); err1 != 0 {
+				goto childerror
+			}
+			r1, _, err1 = RawSyscall(SYS_WRITE, uintptr(fd1), uintptr(unsafe.Pointer(&gidmap[0])), uintptr(len(gidmap)))
+			if err1 != 0 {
+				goto childerror
+			}
+			if _, _, err1 = RawSyscall(SYS_CLOSE, uintptr(fd1), 0, 0); err1 != 0 {
+				goto childerror
+			}
+		}
+
+		if sys.Unshareflags&CLONE_NEWUSER != 0 && sys.UidMappings != nil {
+			dirfd := int(_AT_FDCWD)
+			if fd1, _, err1 = RawSyscall6(SYS_OPENAT, uintptr(dirfd), uintptr(unsafe.Pointer(&puid[0])), uintptr(O_WRONLY), 0, 0, 0); err1 != 0 {
+				goto childerror
+			}
+			r1, _, err1 = RawSyscall(SYS_WRITE, uintptr(fd1), uintptr(unsafe.Pointer(&uidmap[0])), uintptr(len(uidmap)))
+			if err1 != 0 {
+				goto childerror
+			}
+			if _, _, err1 = RawSyscall(SYS_CLOSE, uintptr(fd1), 0, 0); err1 != 0 {
+				goto childerror
+			}
+		}
+
+		// The unshare system call in Linux doesn't unshare mount points
+		// mounted with --shared. Systemd mounts / with --shared. For a
+		// long discussion of the pros and cons of this see debian bug 739593.
+		// The Go model of unsharing is more like Plan 9, where you ask
+		// to unshare and the namespaces are unconditionally unshared.
+		// To make this model work we must further mark / as MS_PRIVATE.
+		// This is what the standard unshare command does.
+		if sys.Unshareflags&CLONE_NEWNS == CLONE_NEWNS {
+			_, _, err1 = RawSyscall6(SYS_MOUNT, uintptr(unsafe.Pointer(&none[0])), uintptr(unsafe.Pointer(&slash[0])), 0, MS_REC|MS_PRIVATE, 0, 0)
+			if err1 != 0 {
+				goto childerror
+			}
+		}
+	}
+
+	// Chroot
+	if chroot != nil {
+		_, _, err1 = RawSyscall(SYS_CHROOT, uintptr(unsafe.Pointer(chroot)), 0, 0)
+		if err1 != 0 {
+			goto childerror
+		}
+	}
+
+	// User and groups
+	if cred := sys.Credential; cred != nil {
+		ngroups := uintptr(len(cred.Groups))
+		groups := uintptr(0)
+		if ngroups > 0 {
+			groups = uintptr(unsafe.Pointer(&cred.Groups[0]))
+		}
+		if !(sys.GidMappings != nil && !sys.GidMappingsEnableSetgroups && ngroups == 0) && !cred.NoSetGroups {
+			_, _, err1 = RawSyscall(_SYS_setgroups, ngroups, groups, 0)
+			if err1 != 0 {
+				goto childerror
+			}
+		}
+		_, _, err1 = RawSyscall(sys_SETGID, uintptr(cred.Gid), 0, 0)
+		if err1 != 0 {
+			goto childerror
+		}
+		_, _, err1 = RawSyscall(sys_SETUID, uintptr(cred.Uid), 0, 0)
+		if err1 != 0 {
+			goto childerror
+		}
+	}
+
+	if len(sys.AmbientCaps) != 0 {
+		// Ambient capabilities were added in the 4.3 kernel,
+		// so it is safe to always use _LINUX_CAPABILITY_VERSION_3.
+		caps.hdr.version = _LINUX_CAPABILITY_VERSION_3
+
+		if _, _, err1 := RawSyscall(SYS_CAPGET, uintptr(unsafe.Pointer(&caps.hdr)), uintptr(unsafe.Pointer(&caps.data[0])), 0); err1 != 0 {
+			goto childerror
+		}
+
+		for _, c := range sys.AmbientCaps {
+			// Add the c capability to the permitted and inheritable capability mask,
+			// otherwise we will not be able to add it to the ambient capability mask.
+			caps.data[capToIndex(c)].permitted |= capToMask(c)
+			caps.data[capToIndex(c)].inheritable |= capToMask(c)
+		}
+
+		if _, _, err1 := RawSyscall(SYS_CAPSET, uintptr(unsafe.Pointer(&caps.hdr)), uintptr(unsafe.Pointer(&caps.data[0])), 0); err1 != 0 {
+			goto childerror
+		}
+
+		for _, c := range sys.AmbientCaps {
+			_, _, err1 = RawSyscall6(SYS_PRCTL, PR_CAP_AMBIENT, uintptr(PR_CAP_AMBIENT_RAISE), c, 0, 0, 0)
+			if err1 != 0 {
+				goto childerror
+			}
+		}
+	}
+
+	// Chdir
+	if dir != nil {
+		_, _, err1 = RawSyscall(SYS_CHDIR, uintptr(unsafe.Pointer(dir)), 0, 0)
+		if err1 != 0 {
+			goto childerror
+		}
+	}
+
+	// Parent death signal
+	if sys.Pdeathsig != 0 {
+		_, _, err1 = RawSyscall6(SYS_PRCTL, PR_SET_PDEATHSIG, uintptr(sys.Pdeathsig), 0, 0, 0, 0)
+		if err1 != 0 {
+			goto childerror
+		}
+
+		// Signal self if parent is already dead. This might cause a
+		// duplicate signal in rare cases, but it won't matter when
+		// using SIGKILL.
+		r1, _ = rawSyscallNoError(SYS_GETPPID, 0, 0, 0)
+		if r1 != ppid {
+			pid, _ := rawSyscallNoError(SYS_GETPID, 0, 0, 0)
+			_, _, err1 := RawSyscall(SYS_KILL, pid, uintptr(sys.Pdeathsig), 0)
+			if err1 != 0 {
+				goto childerror
+			}
+		}
+	}
+
+	// Pass 1: look for fd[i] < i and move those up above len(fd)
+	// so that pass 2 won't stomp on an fd it needs later.
+	if pipe < nextfd {
+		_, _, err1 = RawSyscall(SYS_DUP3, uintptr(pipe), uintptr(nextfd), O_CLOEXEC)
+		if err1 != 0 {
+			goto childerror
+		}
+		pipe = nextfd
+		nextfd++
+	}
+	for i = 0; i < len(fd); i++ {
+		if fd[i] >= 0 && fd[i] < int(i) {
+			if nextfd == pipe { // don't stomp on pipe
+				nextfd++
+			}
+			_, _, err1 = RawSyscall(SYS_DUP3, uintptr(fd[i]), uintptr(nextfd), O_CLOEXEC)
+			if err1 != 0 {
+				goto childerror
+			}
+			fd[i] = nextfd
+			nextfd++
+		}
+	}
+
+	// Pass 2: dup fd[i] down onto i.
+	for i = 0; i < len(fd); i++ {
+		if fd[i] == -1 {
+			RawSyscall(SYS_CLOSE, uintptr(i), 0, 0)
+			continue
+		}
+		if fd[i] == int(i) {
+			// dup2(i, i) won't clear close-on-exec flag on Linux,
+			// probably not elsewhere either.
+			_, _, err1 = RawSyscall(fcntl64Syscall, uintptr(fd[i]), F_SETFD, 0)
+			if err1 != 0 {
+				goto childerror
+			}
+			continue
+		}
+		// The new fd is created NOT close-on-exec,
+		// which is exactly what we want.
+		_, _, err1 = RawSyscall(SYS_DUP3, uintptr(fd[i]), uintptr(i), 0)
+		if err1 != 0 {
+			goto childerror
+		}
+	}
+
+	// By convention, we don't close-on-exec the fds we are
+	// started with, so if len(fd) < 3, close 0, 1, 2 as needed.
+	// Programs that know they inherit fds >= 3 will need
+	// to set them close-on-exec.
+	for i = len(fd); i < 3; i++ {
+		RawSyscall(SYS_CLOSE, uintptr(i), 0, 0)
+	}
+
+	// Detach fd 0 from tty
+	if sys.Noctty {
+		_, _, err1 = RawSyscall(SYS_IOCTL, 0, uintptr(TIOCNOTTY), 0)
+		if err1 != 0 {
+			goto childerror
+		}
+	}
+
+	// Set the controlling TTY to Ctty
+	if sys.Setctty {
+		_, _, err1 = RawSyscall(SYS_IOCTL, uintptr(sys.Ctty), uintptr(TIOCSCTTY), 1)
+		if err1 != 0 {
+			goto childerror
+		}
+	}
+
+	// Enable tracing if requested.
+	// Do this right before exec so that we don't unnecessarily trace the runtime
+	// setting up after the fork. See issue #21428.
+	if sys.Ptrace {
+		_, _, err1 = RawSyscall(SYS_PTRACE, uintptr(PTRACE_TRACEME), 0, 0)
+		if err1 != 0 {
+			goto childerror
+		}
+	}
+
+	// Time to exec.
+	_, _, err1 = RawSyscall(SYS_EXECVE,
+		uintptr(unsafe.Pointer(argv0)),
+		uintptr(unsafe.Pointer(&argv[0])),
+		uintptr(unsafe.Pointer(&envv[0])))
+
+childerror:
+	// send error code on pipe
+	RawSyscall(SYS_WRITE, uintptr(pipe), uintptr(unsafe.Pointer(&err1)), unsafe.Sizeof(err1))
+	for {
+		RawSyscall(SYS_EXIT, 253, 0, 0)
+	}
+}
+
+// Try to open a pipe with O_CLOEXEC set on both file descriptors.
+func forkExecPipe(p []int) (err error) {
+	return Pipe2(p, O_CLOEXEC)
+}
+
+func formatIDMappings(idMap []SysProcIDMap) []byte {
+	var data []byte
+	for _, im := range idMap {
+		data = append(data, []byte(itoa.Itoa(im.ContainerID)+" "+itoa.Itoa(im.HostID)+" "+itoa.Itoa(im.Size)+"\n")...)
+	}
+	return data
+}
+
+// writeIDMappings writes the user namespace User ID or Group ID mappings to the specified path.
+func writeIDMappings(path string, idMap []SysProcIDMap) error {
+	fd, err := Open(path, O_RDWR, 0)
+	if err != nil {
+		return err
+	}
+
+	if _, err := Write(fd, formatIDMappings(idMap)); err != nil {
+		Close(fd)
+		return err
+	}
+
+	if err := Close(fd); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// writeSetgroups writes to /proc/PID/setgroups "deny" if enable is false
+// and "allow" if enable is true.
+// This is needed since kernel 3.19, because you can't write gid_map without
+// disabling setgroups() system call.
+func writeSetgroups(pid int, enable bool) error {
+	sgf := "/proc/" + itoa.Itoa(pid) + "/setgroups"
+	fd, err := Open(sgf, O_RDWR, 0)
+	if err != nil {
+		return err
+	}
+
+	var data []byte
+	if enable {
+		data = []byte("allow")
+	} else {
+		data = []byte("deny")
+	}
+
+	if _, err := Write(fd, data); err != nil {
+		Close(fd)
+		return err
+	}
+
+	return Close(fd)
+}
+
+// writeUidGidMappings writes User ID and Group ID mappings for user namespaces
+// for a process and it is called from the parent process.
+func writeUidGidMappings(pid int, sys *SysProcAttr) error {
+	if sys.UidMappings != nil {
+		uidf := "/proc/" + itoa.Itoa(pid) + "/uid_map"
+		if err := writeIDMappings(uidf, sys.UidMappings); err != nil {
+			return err
+		}
+	}
+
+	if sys.GidMappings != nil {
+		// If the kernel is too old to support /proc/PID/setgroups, writeSetGroups will return ENOENT; this is OK.
+		if err := writeSetgroups(pid, sys.GidMappingsEnableSetgroups); err != nil && err != ENOENT {
+			return err
+		}
+		gidf := "/proc/" + itoa.Itoa(pid) + "/gid_map"
+		if err := writeIDMappings(gidf, sys.GidMappings); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
diff --git a/contrib/go/_std_1.19/src/syscall/exec_unix.go b/contrib/go/_std_1.19/src/syscall/exec_unix.go
new file mode 100644
index 0000000000..286be454d8
--- /dev/null
+++ b/contrib/go/_std_1.19/src/syscall/exec_unix.go
@@ -0,0 +1,306 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix
+
+// Fork, exec, wait, etc.
+
+package syscall
+
+import (
+	errorspkg "errors"
+	"internal/bytealg"
+	"runtime"
+	"sync"
+	"unsafe"
+)
+
+// Lock synchronizing creation of new file descriptors with fork.
+//
+// We want the child in a fork/exec sequence to inherit only the
+// file descriptors we intend. To do that, we mark all file
+// descriptors close-on-exec and then, in the child, explicitly
+// unmark the ones we want the exec'ed program to keep.
+// Unix doesn't make this easy: there is, in general, no way to
+// allocate a new file descriptor close-on-exec. Instead you
+// have to allocate the descriptor and then mark it close-on-exec.
+// If a fork happens between those two events, the child's exec
+// will inherit an unwanted file descriptor.
+//
+// This lock solves that race: the create new fd/mark close-on-exec
+// operation is done holding ForkLock for reading, and the fork itself
+// is done holding ForkLock for writing. At least, that's the idea.
+// There are some complications.
+//
+// Some system calls that create new file descriptors can block
+// for arbitrarily long times: open on a hung NFS server or named
+// pipe, accept on a socket, and so on. We can't reasonably grab
+// the lock across those operations.
+//
+// It is worse to inherit some file descriptors than others.
+// If a non-malicious child accidentally inherits an open ordinary file,
+// that's not a big deal. On the other hand, if a long-lived child
+// accidentally inherits the write end of a pipe, then the reader
+// of that pipe will not see EOF until that child exits, potentially
+// causing the parent program to hang. This is a common problem
+// in threaded C programs that use popen.
+//
+// Luckily, the file descriptors that are most important not to
+// inherit are not the ones that can take an arbitrarily long time
+// to create: pipe returns instantly, and the net package uses
+// non-blocking I/O to accept on a listening socket.
+// The rules for which file descriptor-creating operations use the
+// ForkLock are as follows:
+//
+// 1) Pipe. Does not block. Use the ForkLock.
+// 2) Socket. Does not block. Use the ForkLock.
+// 3) Accept. If using non-blocking mode, use the ForkLock.
+//             Otherwise, live with the race.
+// 4) Open. Can block. Use O_CLOEXEC if available (Linux).
+//             Otherwise, live with the race.
+// 5) Dup. Does not block. Use the ForkLock.
+//             On Linux, could use fcntl F_DUPFD_CLOEXEC
+//             instead of the ForkLock, but only for dup(fd, -1).
+
+var ForkLock sync.RWMutex
+
+// StringSlicePtr converts a slice of strings to a slice of pointers
+// to NUL-terminated byte arrays. If any string contains a NUL byte
+// this function panics instead of returning an error.
+//
+// Deprecated: Use SlicePtrFromStrings instead.
+func StringSlicePtr(ss []string) []*byte {
+	bb := make([]*byte, len(ss)+1)
+	for i := 0; i < len(ss); i++ {
+		bb[i] = StringBytePtr(ss[i])
+	}
+	bb[len(ss)] = nil
+	return bb
+}
+
+// SlicePtrFromStrings converts a slice of strings to a slice of
+// pointers to NUL-terminated byte arrays. If any string contains
+// a NUL byte, it returns (nil, EINVAL).
+func SlicePtrFromStrings(ss []string) ([]*byte, error) {
+	n := 0
+	for _, s := range ss {
+		if bytealg.IndexByteString(s, 0) != -1 {
+			return nil, EINVAL
+		}
+		n += len(s) + 1 // +1 for NUL
+	}
+	bb := make([]*byte, len(ss)+1)
+	b := make([]byte, n)
+	n = 0
+	for i, s := range ss {
+		bb[i] = &b[n]
+		copy(b[n:], s)
+		n += len(s) + 1
+	}
+	return bb, nil
+}
+
+func CloseOnExec(fd int) { fcntl(fd, F_SETFD, FD_CLOEXEC) }
+
+func SetNonblock(fd int, nonblocking bool) (err error) {
+	flag, err := fcntl(fd, F_GETFL, 0)
+	if err != nil {
+		return err
+	}
+	if nonblocking {
+		flag |= O_NONBLOCK
+	} else {
+		flag &^= O_NONBLOCK
+	}
+	_, err = fcntl(fd, F_SETFL, flag)
+	return err
+}
+
+// Credential holds user and group identities to be assumed
+// by a child process started by StartProcess.
+type Credential struct {
+	Uid         uint32   // User ID.
+	Gid         uint32   // Group ID.
+	Groups      []uint32 // Supplementary group IDs.
+	NoSetGroups bool     // If true, don't set supplementary groups
+}
+
+// ProcAttr holds attributes that will be applied to a new process started
+// by StartProcess.
+type ProcAttr struct {
+	Dir   string    // Current working directory.
+	Env   []string  // Environment.
+	Files []uintptr // File descriptors.
+	Sys   *SysProcAttr
+}
+
+var zeroProcAttr ProcAttr
+var zeroSysProcAttr SysProcAttr
+
+func forkExec(argv0 string, argv []string, attr *ProcAttr) (pid int, err error) {
+	var p [2]int
+	var n int
+	var err1 Errno
+	var wstatus WaitStatus
+
+	if attr == nil {
+		attr = &zeroProcAttr
+	}
+	sys := attr.Sys
+	if sys == nil {
+		sys = &zeroSysProcAttr
+	}
+
+	// Convert args to C form.
+	argv0p, err := BytePtrFromString(argv0)
+	if err != nil {
+		return 0, err
+	}
+	argvp, err := SlicePtrFromStrings(argv)
+	if err != nil {
+		return 0, err
+	}
+	envvp, err := SlicePtrFromStrings(attr.Env)
+	if err != nil {
+		return 0, err
+	}
+
+	if (runtime.GOOS == "freebsd" || runtime.GOOS == "dragonfly") && len(argv[0]) > len(argv0) {
+		argvp[0] = argv0p
+	}
+
+	var chroot *byte
+	if sys.Chroot != "" {
+		chroot, err = BytePtrFromString(sys.Chroot)
+		if err != nil {
+			return 0, err
+		}
+	}
+	var dir *byte
+	if attr.Dir != "" {
+		dir, err = BytePtrFromString(attr.Dir)
+		if err != nil {
+			return 0, err
+		}
+	}
+
+	// Both Setctty and Foreground use the Ctty field,
+	// but they give it slightly different meanings.
+	if sys.Setctty && sys.Foreground {
+		return 0, errorspkg.New("both Setctty and Foreground set in SysProcAttr")
+	}
+	if sys.Setctty && sys.Ctty >= len(attr.Files) {
+		return 0, errorspkg.New("Setctty set but Ctty not valid in child")
+	}
+
+	// Acquire the fork lock so that no other threads
+	// create new fds that are not yet close-on-exec
+	// before we fork.
+	ForkLock.Lock()
+
+	// Allocate child status pipe close on exec.
+	if err = forkExecPipe(p[:]); err != nil {
+		ForkLock.Unlock()
+		return 0, err
+	}
+
+	// Kick off child.
+	pid, err1 = forkAndExecInChild(argv0p, argvp, envvp, chroot, dir, attr, sys, p[1])
+	if err1 != 0 {
+		Close(p[0])
+		Close(p[1])
+		ForkLock.Unlock()
+		return 0, Errno(err1)
+	}
+	ForkLock.Unlock()
+
+	// Read child error status from pipe.
+	Close(p[1])
+	for {
+		n, err = readlen(p[0], (*byte)(unsafe.Pointer(&err1)), int(unsafe.Sizeof(err1)))
+		if err != EINTR {
+			break
+		}
+	}
+	Close(p[0])
+	if err != nil || n != 0 {
+		if n == int(unsafe.Sizeof(err1)) {
+			err = Errno(err1)
+		}
+		if err == nil {
+			err = EPIPE
+		}
+
+		// Child failed; wait for it to exit, to make sure
+		// the zombies don't accumulate.
+		_, err1 := Wait4(pid, &wstatus, 0, nil)
+		for err1 == EINTR {
+			_, err1 = Wait4(pid, &wstatus, 0, nil)
+		}
+		return 0, err
+	}
+
+	// Read got EOF, so pipe closed on exec, so exec succeeded.
+	return pid, nil
+}
+
+// Combination of fork and exec, careful to be thread safe.
+func ForkExec(argv0 string, argv []string, attr *ProcAttr) (pid int, err error) {
+	return forkExec(argv0, argv, attr)
+}
+
+// StartProcess wraps ForkExec for package os.
+func StartProcess(argv0 string, argv []string, attr *ProcAttr) (pid int, handle uintptr, err error) {
+	pid, err = forkExec(argv0, argv, attr)
+	return pid, 0, err
+}
+
+// Implemented in runtime package.
+func runtime_BeforeExec()
+func runtime_AfterExec()
+
+// execveLibc is non-nil on OS using libc syscall, set to execve in exec_libc.go; this
+// avoids a build dependency for other platforms.
+var execveLibc func(path uintptr, argv uintptr, envp uintptr) Errno
+var execveDarwin func(path *byte, argv **byte, envp **byte) error
+var execveOpenBSD func(path *byte, argv **byte, envp **byte) error
+
+// Exec invokes the execve(2) system call.
+func Exec(argv0 string, argv []string, envv []string) (err error) {
+	argv0p, err := BytePtrFromString(argv0)
+	if err != nil {
+		return err
+	}
+	argvp, err := SlicePtrFromStrings(argv)
+	if err != nil {
+		return err
+	}
+	envvp, err := SlicePtrFromStrings(envv)
+	if err != nil {
+		return err
+	}
+	runtime_BeforeExec()
+
+	var err1 error
+	if runtime.GOOS == "solaris" || runtime.GOOS == "illumos" || runtime.GOOS == "aix" {
+		// RawSyscall should never be used on Solaris, illumos, or AIX.
+		err1 = execveLibc(
+			uintptr(unsafe.Pointer(argv0p)),
+			uintptr(unsafe.Pointer(&argvp[0])),
+			uintptr(unsafe.Pointer(&envvp[0])))
+	} else if runtime.GOOS == "darwin" || runtime.GOOS == "ios" {
+		// Similarly on Darwin.
+		err1 = execveDarwin(argv0p, &argvp[0], &envvp[0])
+	} else if runtime.GOOS == "openbsd" && (runtime.GOARCH == "386" || runtime.GOARCH == "amd64" || runtime.GOARCH == "arm" || runtime.GOARCH == "arm64") {
+		// Similarly on OpenBSD.
+		err1 = execveOpenBSD(argv0p, &argvp[0], &envvp[0])
+	} else {
+		_, _, err1 = RawSyscall(SYS_EXECVE,
+			uintptr(unsafe.Pointer(argv0p)),
+			uintptr(unsafe.Pointer(&argvp[0])),
+			uintptr(unsafe.Pointer(&envvp[0])))
+	}
+	runtime_AfterExec()
+	return err1
+}
diff --git a/contrib/go/_std_1.18/src/syscall/flock.go b/contrib/go/_std_1.19/src/syscall/flock.go
index 8cb8f16153..8cb8f16153 100644
--- a/contrib/go/_std_1.18/src/syscall/flock.go
+++ b/contrib/go/_std_1.19/src/syscall/flock.go
diff --git a/contrib/go/_std_1.18/src/syscall/flock_darwin.go b/contrib/go/_std_1.19/src/syscall/flock_darwin.go
index d2bd84130c..d2bd84130c 100644
--- a/contrib/go/_std_1.18/src/syscall/flock_darwin.go
+++ b/contrib/go/_std_1.19/src/syscall/flock_darwin.go
diff --git a/contrib/go/_std_1.19/src/syscall/forkpipe.go b/contrib/go/_std_1.19/src/syscall/forkpipe.go
new file mode 100644
index 0000000000..5082abc41c
--- /dev/null
+++ b/contrib/go/_std_1.19/src/syscall/forkpipe.go
@@ -0,0 +1,21 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build aix || darwin
+
+package syscall
+
+// Try to open a pipe with O_CLOEXEC set on both file descriptors.
+func forkExecPipe(p []int) error {
+	err := Pipe(p)
+	if err != nil {
+		return err
+	}
+	_, err = fcntl(p[0], F_SETFD, FD_CLOEXEC)
+	if err != nil {
+		return err
+	}
+	_, err = fcntl(p[1], F_SETFD, FD_CLOEXEC)
+	return err
+}
diff --git a/contrib/go/_std_1.18/src/syscall/lsf_linux.go b/contrib/go/_std_1.19/src/syscall/lsf_linux.go
index 28e96d54e6..28e96d54e6 100644
--- a/contrib/go/_std_1.18/src/syscall/lsf_linux.go
+++ b/contrib/go/_std_1.19/src/syscall/lsf_linux.go
diff --git a/contrib/go/_std_1.18/src/syscall/msan0.go b/contrib/go/_std_1.19/src/syscall/msan0.go
index fba8a5f716..fba8a5f716 100644
--- a/contrib/go/_std_1.18/src/syscall/msan0.go
+++ b/contrib/go/_std_1.19/src/syscall/msan0.go
diff --git a/contrib/go/_std_1.18/src/syscall/net.go b/contrib/go/_std_1.19/src/syscall/net.go
index 531fa80d8f..531fa80d8f 100644
--- a/contrib/go/_std_1.18/src/syscall/net.go
+++ b/contrib/go/_std_1.19/src/syscall/net.go
diff --git a/contrib/go/_std_1.18/src/syscall/netlink_linux.go b/contrib/go/_std_1.19/src/syscall/netlink_linux.go
index 2d810705bf..2d810705bf 100644
--- a/contrib/go/_std_1.18/src/syscall/netlink_linux.go
+++ b/contrib/go/_std_1.19/src/syscall/netlink_linux.go
diff --git a/contrib/go/_std_1.18/src/syscall/ptrace_darwin.go b/contrib/go/_std_1.19/src/syscall/ptrace_darwin.go
index 519e451c73..519e451c73 100644
--- a/contrib/go/_std_1.18/src/syscall/ptrace_darwin.go
+++ b/contrib/go/_std_1.19/src/syscall/ptrace_darwin.go
diff --git a/contrib/go/_std_1.18/src/syscall/route_bsd.go b/contrib/go/_std_1.19/src/syscall/route_bsd.go
index 8e47ff888e..8e47ff888e 100644
--- a/contrib/go/_std_1.18/src/syscall/route_bsd.go
+++ b/contrib/go/_std_1.19/src/syscall/route_bsd.go
diff --git a/contrib/go/_std_1.18/src/syscall/route_darwin.go b/contrib/go/_std_1.19/src/syscall/route_darwin.go
index b0636ed07c..b0636ed07c 100644
--- a/contrib/go/_std_1.18/src/syscall/route_darwin.go
+++ b/contrib/go/_std_1.19/src/syscall/route_darwin.go
diff --git a/contrib/go/_std_1.18/src/syscall/setuidgid_linux.go b/contrib/go/_std_1.19/src/syscall/setuidgid_linux.go
index c995d258eb..c995d258eb 100644
--- a/contrib/go/_std_1.18/src/syscall/setuidgid_linux.go
+++ b/contrib/go/_std_1.19/src/syscall/setuidgid_linux.go
diff --git a/contrib/go/_std_1.18/src/syscall/sock_cloexec_linux.go b/contrib/go/_std_1.19/src/syscall/sock_cloexec_linux.go
index 600cf25c15..600cf25c15 100644
--- a/contrib/go/_std_1.18/src/syscall/sock_cloexec_linux.go
+++ b/contrib/go/_std_1.19/src/syscall/sock_cloexec_linux.go
diff --git a/contrib/go/_std_1.18/src/syscall/sockcmsg_linux.go b/contrib/go/_std_1.19/src/syscall/sockcmsg_linux.go
index d97667cf7e..d97667cf7e 100644
--- a/contrib/go/_std_1.18/src/syscall/sockcmsg_linux.go
+++ b/contrib/go/_std_1.19/src/syscall/sockcmsg_linux.go
diff --git a/contrib/go/_std_1.19/src/syscall/sockcmsg_unix.go b/contrib/go/_std_1.19/src/syscall/sockcmsg_unix.go
new file mode 100644
index 0000000000..6ade73e87e
--- /dev/null
+++ b/contrib/go/_std_1.19/src/syscall/sockcmsg_unix.go
@@ -0,0 +1,92 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix
+
+// Socket control messages
+
+package syscall
+
+import (
+	"unsafe"
+)
+
+// CmsgLen returns the value to store in the Len field of the Cmsghdr
+// structure, taking into account any necessary alignment.
+func CmsgLen(datalen int) int {
+	return cmsgAlignOf(SizeofCmsghdr) + datalen
+}
+
+// CmsgSpace returns the number of bytes an ancillary element with
+// payload of the passed data length occupies.
+func CmsgSpace(datalen int) int {
+	return cmsgAlignOf(SizeofCmsghdr) + cmsgAlignOf(datalen)
+}
+
+func (h *Cmsghdr) data(offset uintptr) unsafe.Pointer {
+	return unsafe.Pointer(uintptr(unsafe.Pointer(h)) + uintptr(cmsgAlignOf(SizeofCmsghdr)) + offset)
+}
+
+// SocketControlMessage represents a socket control message.
+type SocketControlMessage struct {
+	Header Cmsghdr
+	Data   []byte
+}
+
+// ParseSocketControlMessage parses b as an array of socket control
+// messages.
+func ParseSocketControlMessage(b []byte) ([]SocketControlMessage, error) {
+	var msgs []SocketControlMessage
+	i := 0
+	for i+CmsgLen(0) <= len(b) {
+		h, dbuf, err := socketControlMessageHeaderAndData(b[i:])
+		if err != nil {
+			return nil, err
+		}
+		m := SocketControlMessage{Header: *h, Data: dbuf}
+		msgs = append(msgs, m)
+		i += cmsgAlignOf(int(h.Len))
+	}
+	return msgs, nil
+}
+
+func socketControlMessageHeaderAndData(b []byte) (*Cmsghdr, []byte, error) {
+	h := (*Cmsghdr)(unsafe.Pointer(&b[0]))
+	if h.Len < SizeofCmsghdr || uint64(h.Len) > uint64(len(b)) {
+		return nil, nil, EINVAL
+	}
+	return h, b[cmsgAlignOf(SizeofCmsghdr):h.Len], nil
+}
+
+// UnixRights encodes a set of open file descriptors into a socket
+// control message for sending to another process.
+func UnixRights(fds ...int) []byte {
+	datalen := len(fds) * 4
+	b := make([]byte, CmsgSpace(datalen))
+	h := (*Cmsghdr)(unsafe.Pointer(&b[0]))
+	h.Level = SOL_SOCKET
+	h.Type = SCM_RIGHTS
+	h.SetLen(CmsgLen(datalen))
+	for i, fd := range fds {
+		*(*int32)(h.data(4 * uintptr(i))) = int32(fd)
+	}
+	return b
+}
+
+// ParseUnixRights decodes a socket control message that contains an
+// integer array of open file descriptors from another process.
+func ParseUnixRights(m *SocketControlMessage) ([]int, error) {
+	if m.Header.Level != SOL_SOCKET {
+		return nil, EINVAL
+	}
+	if m.Header.Type != SCM_RIGHTS {
+		return nil, EINVAL
+	}
+	fds := make([]int, len(m.Data)>>2)
+	for i, j := 0, 0; i < len(m.Data); i += 4 {
+		fds[j] = int(*(*int32)(unsafe.Pointer(&m.Data[i])))
+		j++
+	}
+	return fds, nil
+}
diff --git a/contrib/go/_std_1.18/src/syscall/sockcmsg_unix_other.go b/contrib/go/_std_1.19/src/syscall/sockcmsg_unix_other.go
index 845bd9df99..845bd9df99 100644
--- a/contrib/go/_std_1.18/src/syscall/sockcmsg_unix_other.go
+++ b/contrib/go/_std_1.19/src/syscall/sockcmsg_unix_other.go
diff --git a/contrib/go/_std_1.19/src/syscall/syscall.go b/contrib/go/_std_1.19/src/syscall/syscall.go
new file mode 100644
index 0000000000..62bfa449cf
--- /dev/null
+++ b/contrib/go/_std_1.19/src/syscall/syscall.go
@@ -0,0 +1,102 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package syscall contains an interface to the low-level operating system
+// primitives. The details vary depending on the underlying system, and
+// by default, godoc will display the syscall documentation for the current
+// system. If you want godoc to display syscall documentation for another
+// system, set $GOOS and $GOARCH to the desired system. For example, if
+// you want to view documentation for freebsd/arm on linux/amd64, set $GOOS
+// to freebsd and $GOARCH to arm.
+// The primary use of syscall is inside other packages that provide a more
+// portable interface to the system, such as "os", "time" and "net".  Use
+// those packages rather than this one if you can.
+// For details of the functions and data types in this package consult
+// the manuals for the appropriate operating system.
+// These calls return err == nil to indicate success; otherwise
+// err is an operating system error describing the failure.
+// On most systems, that error has type syscall.Errno.
+//
+// Deprecated: this package is locked down. Callers should use the
+// corresponding package in the golang.org/x/sys repository instead.
+// That is also where updates required by new systems or versions
+// should be applied. See https://golang.org/s/go1.4-syscall for more
+// information.
+package syscall
+
+import "internal/bytealg"
+
+//go:generate go run ./mksyscall_windows.go -systemdll -output zsyscall_windows.go syscall_windows.go security_windows.go
+
+// StringByteSlice converts a string to a NUL-terminated []byte,
+// If s contains a NUL byte this function panics instead of
+// returning an error.
+//
+// Deprecated: Use ByteSliceFromString instead.
+func StringByteSlice(s string) []byte {
+	a, err := ByteSliceFromString(s)
+	if err != nil {
+		panic("syscall: string with NUL passed to StringByteSlice")
+	}
+	return a
+}
+
+// ByteSliceFromString returns a NUL-terminated slice of bytes
+// containing the text of s. If s contains a NUL byte at any
+// location, it returns (nil, EINVAL).
+func ByteSliceFromString(s string) ([]byte, error) {
+	if bytealg.IndexByteString(s, 0) != -1 {
+		return nil, EINVAL
+	}
+	a := make([]byte, len(s)+1)
+	copy(a, s)
+	return a, nil
+}
+
+// StringBytePtr returns a pointer to a NUL-terminated array of bytes.
+// If s contains a NUL byte this function panics instead of returning
+// an error.
+//
+// Deprecated: Use BytePtrFromString instead.
+func StringBytePtr(s string) *byte { return &StringByteSlice(s)[0] }
+
+// BytePtrFromString returns a pointer to a NUL-terminated array of
+// bytes containing the text of s. If s contains a NUL byte at any
+// location, it returns (nil, EINVAL).
+func BytePtrFromString(s string) (*byte, error) {
+	a, err := ByteSliceFromString(s)
+	if err != nil {
+		return nil, err
+	}
+	return &a[0], nil
+}
+
+// Single-word zero for use when we need a valid pointer to 0 bytes.
+// See mksyscall.pl.
+var _zero uintptr
+
+// Unix returns the time stored in ts as seconds plus nanoseconds.
+func (ts *Timespec) Unix() (sec int64, nsec int64) {
+	return int64(ts.Sec), int64(ts.Nsec)
+}
+
+// Unix returns the time stored in tv as seconds plus nanoseconds.
+func (tv *Timeval) Unix() (sec int64, nsec int64) {
+	return int64(tv.Sec), int64(tv.Usec) * 1000
+}
+
+// Nano returns the time stored in ts as nanoseconds.
+func (ts *Timespec) Nano() int64 {
+	return int64(ts.Sec)*1e9 + int64(ts.Nsec)
+}
+
+// Nano returns the time stored in tv as nanoseconds.
+func (tv *Timeval) Nano() int64 {
+	return int64(tv.Sec)*1e9 + int64(tv.Usec)*1000
+}
+
+// Getpagesize and Exit are provided by the runtime.
+
+func Getpagesize() int
+func Exit(code int)
diff --git a/contrib/go/_std_1.18/src/syscall/syscall_bsd.go b/contrib/go/_std_1.19/src/syscall/syscall_bsd.go
index 5e636d5258..5e636d5258 100644
--- a/contrib/go/_std_1.18/src/syscall/syscall_bsd.go
+++ b/contrib/go/_std_1.19/src/syscall/syscall_bsd.go
diff --git a/contrib/go/_std_1.19/src/syscall/syscall_darwin.go b/contrib/go/_std_1.19/src/syscall/syscall_darwin.go
new file mode 100644
index 0000000000..663bd98c10
--- /dev/null
+++ b/contrib/go/_std_1.19/src/syscall/syscall_darwin.go
@@ -0,0 +1,339 @@
+// Copyright 2009,2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Darwin system calls.
+// This file is compiled as ordinary Go code,
+// but it is also input to mksyscall,
+// which parses the //sys lines and generates system call stubs.
+// Note that sometimes we use a lowercase //sys name and wrap
+// it in our own nicer implementation, either here or in
+// syscall_bsd.go or syscall_unix.go.
+
+package syscall
+
+import (
+	"internal/abi"
+	"unsafe"
+)
+
+func Syscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno)
+func Syscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno)
+func RawSyscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno)
+func RawSyscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno)
+
+var dupTrampoline = abi.FuncPCABI0(libc_dup2_trampoline)
+
+type SockaddrDatalink struct {
+	Len    uint8
+	Family uint8
+	Index  uint16
+	Type   uint8
+	Nlen   uint8
+	Alen   uint8
+	Slen   uint8
+	Data   [12]int8
+	raw    RawSockaddrDatalink
+}
+
+// Translate "kern.hostname" to []_C_int{0,1,2,3}.
+func nametomib(name string) (mib []_C_int, err error) {
+	const siz = unsafe.Sizeof(mib[0])
+
+	// NOTE(rsc): It seems strange to set the buffer to have
+	// size CTL_MAXNAME+2 but use only CTL_MAXNAME
+	// as the size. I don't know why the +2 is here, but the
+	// kernel uses +2 for its own implementation of this function.
+	// I am scared that if we don't include the +2 here, the kernel
+	// will silently write 2 words farther than we specify
+	// and we'll get memory corruption.
+	var buf [CTL_MAXNAME + 2]_C_int
+	n := uintptr(CTL_MAXNAME) * siz
+
+	p := (*byte)(unsafe.Pointer(&buf[0]))
+	bytes, err := ByteSliceFromString(name)
+	if err != nil {
+		return nil, err
+	}
+
+	// Magic sysctl: "setting" 0.3 to a string name
+	// lets you read back the array of integers form.
+	if err = sysctl([]_C_int{0, 3}, p, &n, &bytes[0], uintptr(len(name))); err != nil {
+		return nil, err
+	}
+	return buf[0 : n/siz], nil
+}
+
+func direntIno(buf []byte) (uint64, bool) {
+	return readInt(buf, unsafe.Offsetof(Dirent{}.Ino), unsafe.Sizeof(Dirent{}.Ino))
+}
+
+func direntReclen(buf []byte) (uint64, bool) {
+	return readInt(buf, unsafe.Offsetof(Dirent{}.Reclen), unsafe.Sizeof(Dirent{}.Reclen))
+}
+
+func direntNamlen(buf []byte) (uint64, bool) {
+	return readInt(buf, unsafe.Offsetof(Dirent{}.Namlen), unsafe.Sizeof(Dirent{}.Namlen))
+}
+
+func PtraceAttach(pid int) (err error) { return ptrace(PT_ATTACH, pid, 0, 0) }
+func PtraceDetach(pid int) (err error) { return ptrace(PT_DETACH, pid, 0, 0) }
+
+//sysnb pipe(p *[2]int32) (err error)
+
+func Pipe(p []int) (err error) {
+	if len(p) != 2 {
+		return EINVAL
+	}
+	var q [2]int32
+	err = pipe(&q)
+	if err == nil {
+		p[0] = int(q[0])
+		p[1] = int(q[1])
+	}
+	return
+}
+
+func Getfsstat(buf []Statfs_t, flags int) (n int, err error) {
+	var _p0 unsafe.Pointer
+	var bufsize uintptr
+	if len(buf) > 0 {
+		_p0 = unsafe.Pointer(&buf[0])
+		bufsize = unsafe.Sizeof(Statfs_t{}) * uintptr(len(buf))
+	}
+	r0, _, e1 := syscall(abi.FuncPCABI0(libc_getfsstat_trampoline), uintptr(_p0), bufsize, uintptr(flags))
+	n = int(r0)
+	if e1 != 0 {
+		err = e1
+	}
+	return
+}
+
+func libc_getfsstat_trampoline()
+
+//go:cgo_import_dynamic libc_getfsstat getfsstat "/usr/lib/libSystem.B.dylib"
+
+//sys	utimensat(dirfd int, path string, times *[2]Timespec, flags int) (err error)
+
+/*
+ * Wrapped
+ */
+
+//sys	kill(pid int, signum int, posix int) (err error)
+
+func Kill(pid int, signum Signal) (err error) { return kill(pid, int(signum), 1) }
+
+/*
+ * Exposed directly
+ */
+//sys	Access(path string, mode uint32) (err error)
+//sys	Adjtime(delta *Timeval, olddelta *Timeval) (err error)
+//sys	Chdir(path string) (err error)
+//sys	Chflags(path string, flags int) (err error)
+//sys	Chmod(path string, mode uint32) (err error)
+//sys	Chown(path string, uid int, gid int) (err error)
+//sys	Chroot(path string) (err error)
+//sys	Close(fd int) (err error)
+//sys	closedir(dir uintptr) (err error)
+//sys	Dup(fd int) (nfd int, err error)
+//sys	Dup2(from int, to int) (err error)
+//sys	Exchangedata(path1 string, path2 string, options int) (err error)
+//sys	Fchdir(fd int) (err error)
+//sys	Fchflags(fd int, flags int) (err error)
+//sys	Fchmod(fd int, mode uint32) (err error)
+//sys	Fchown(fd int, uid int, gid int) (err error)
+//sys	Flock(fd int, how int) (err error)
+//sys	Fpathconf(fd int, name int) (val int, err error)
+//sys	Fsync(fd int) (err error)
+//  Fsync is not called for os.File.Sync(). Please see internal/poll/fd_fsync_darwin.go
+//sys	Ftruncate(fd int, length int64) (err error)
+//sys	Getdtablesize() (size int)
+//sysnb	Getegid() (egid int)
+//sysnb	Geteuid() (uid int)
+//sysnb	Getgid() (gid int)
+//sysnb	Getpgid(pid int) (pgid int, err error)
+//sysnb	Getpgrp() (pgrp int)
+//sysnb	Getpid() (pid int)
+//sysnb	Getppid() (ppid int)
+//sys	Getpriority(which int, who int) (prio int, err error)
+//sysnb	Getrlimit(which int, lim *Rlimit) (err error)
+//sysnb	Getrusage(who int, rusage *Rusage) (err error)
+//sysnb	Getsid(pid int) (sid int, err error)
+//sysnb	Getuid() (uid int)
+//sysnb	Issetugid() (tainted bool)
+//sys	Kqueue() (fd int, err error)
+//sys	Lchown(path string, uid int, gid int) (err error)
+//sys	Link(path string, link string) (err error)
+//sys	Listen(s int, backlog int) (err error)
+//sys	Mkdir(path string, mode uint32) (err error)
+//sys	Mkfifo(path string, mode uint32) (err error)
+//sys	Mknod(path string, mode uint32, dev int) (err error)
+//sys	Mlock(b []byte) (err error)
+//sys	Mlockall(flags int) (err error)
+//sys	Mprotect(b []byte, prot int) (err error)
+//sys	Munlock(b []byte) (err error)
+//sys	Munlockall() (err error)
+//sys	Open(path string, mode int, perm uint32) (fd int, err error)
+//sys	Pathconf(path string, name int) (val int, err error)
+//sys	pread(fd int, p []byte, offset int64) (n int, err error)
+//sys	pwrite(fd int, p []byte, offset int64) (n int, err error)
+//sys	read(fd int, p []byte) (n int, err error)
+//sys	readdir_r(dir uintptr, entry *Dirent, result **Dirent) (res Errno)
+//sys	Readlink(path string, buf []byte) (n int, err error)
+//sys	Rename(from string, to string) (err error)
+//sys	Revoke(path string) (err error)
+//sys	Rmdir(path string) (err error)
+//sys	Seek(fd int, offset int64, whence int) (newoffset int64, err error) = SYS_lseek
+//sys	Select(n int, r *FdSet, w *FdSet, e *FdSet, timeout *Timeval) (err error)
+//sys	Setegid(egid int) (err error)
+//sysnb	Seteuid(euid int) (err error)
+//sysnb	Setgid(gid int) (err error)
+//sys	Setlogin(name string) (err error)
+//sysnb	Setpgid(pid int, pgid int) (err error)
+//sys	Setpriority(which int, who int, prio int) (err error)
+//sys	Setprivexec(flag int) (err error)
+//sysnb	Setregid(rgid int, egid int) (err error)
+//sysnb	Setreuid(ruid int, euid int) (err error)
+//sysnb	Setrlimit(which int, lim *Rlimit) (err error)
+//sysnb	Setsid() (pid int, err error)
+//sysnb	Settimeofday(tp *Timeval) (err error)
+//sysnb	Setuid(uid int) (err error)
+//sys	Symlink(path string, link string) (err error)
+//sys	Sync() (err error)
+//sys	Truncate(path string, length int64) (err error)
+//sys	Umask(newmask int) (oldmask int)
+//sys	Undelete(path string) (err error)
+//sys	Unlink(path string) (err error)
+//sys	Unmount(path string, flags int) (err error)
+//sys	write(fd int, p []byte) (n int, err error)
+//sys	writev(fd int, iovecs []Iovec) (cnt uintptr, err error)
+//sys   mmap(addr uintptr, length uintptr, prot int, flag int, fd int, pos int64) (ret uintptr, err error)
+//sys   munmap(addr uintptr, length uintptr) (err error)
+//sysnb fork() (pid int, err error)
+//sysnb ioctl(fd int, req int, arg int) (err error)
+//sysnb ioctlPtr(fd int, req uint, arg unsafe.Pointer) (err error) = SYS_ioctl
+//sysnb execve(path *byte, argv **byte, envp **byte) (err error)
+//sysnb exit(res int) (err error)
+//sys	sysctl(mib []_C_int, old *byte, oldlen *uintptr, new *byte, newlen uintptr) (err error)
+//sys	fcntlPtr(fd int, cmd int, arg unsafe.Pointer) (val int, err error) = SYS_fcntl
+//sys   unlinkat(fd int, path string, flags int) (err error)
+//sys   openat(fd int, path string, flags int, perm uint32) (fdret int, err error)
+//sys	getcwd(buf []byte) (n int, err error)
+
+func init() {
+	execveDarwin = execve
+}
+
+func fdopendir(fd int) (dir uintptr, err error) {
+	r0, _, e1 := syscallPtr(abi.FuncPCABI0(libc_fdopendir_trampoline), uintptr(fd), 0, 0)
+	dir = uintptr(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_fdopendir_trampoline()
+
+//go:cgo_import_dynamic libc_fdopendir fdopendir "/usr/lib/libSystem.B.dylib"
+
+func readlen(fd int, buf *byte, nbuf int) (n int, err error) {
+	r0, _, e1 := syscall(abi.FuncPCABI0(libc_read_trampoline), uintptr(fd), uintptr(unsafe.Pointer(buf)), uintptr(nbuf))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func writelen(fd int, buf *byte, nbuf int) (n int, err error) {
+	r0, _, e1 := syscall(abi.FuncPCABI0(libc_write_trampoline), uintptr(fd), uintptr(unsafe.Pointer(buf)), uintptr(nbuf))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func Getdirentries(fd int, buf []byte, basep *uintptr) (n int, err error) {
+	// Simulate Getdirentries using fdopendir/readdir_r/closedir.
+	// We store the number of entries to skip in the seek
+	// offset of fd. See issue #31368.
+	// It's not the full required semantics, but should handle the case
+	// of calling Getdirentries or ReadDirent repeatedly.
+	// It won't handle assigning the results of lseek to *basep, or handle
+	// the directory being edited underfoot.
+	skip, err := Seek(fd, 0, 1 /* SEEK_CUR */)
+	if err != nil {
+		return 0, err
+	}
+
+	// We need to duplicate the incoming file descriptor
+	// because the caller expects to retain control of it, but
+	// fdopendir expects to take control of its argument.
+	// Just Dup'ing the file descriptor is not enough, as the
+	// result shares underlying state. Use openat to make a really
+	// new file descriptor referring to the same directory.
+	fd2, err := openat(fd, ".", O_RDONLY, 0)
+	if err != nil {
+		return 0, err
+	}
+	d, err := fdopendir(fd2)
+	if err != nil {
+		Close(fd2)
+		return 0, err
+	}
+	defer closedir(d)
+
+	var cnt int64
+	for {
+		var entry Dirent
+		var entryp *Dirent
+		e := readdir_r(d, &entry, &entryp)
+		if e != 0 {
+			return n, errnoErr(e)
+		}
+		if entryp == nil {
+			break
+		}
+		if skip > 0 {
+			skip--
+			cnt++
+			continue
+		}
+		reclen := int(entry.Reclen)
+		if reclen > len(buf) {
+			// Not enough room. Return for now.
+			// The counter will let us know where we should start up again.
+			// Note: this strategy for suspending in the middle and
+			// restarting is O(n^2) in the length of the directory. Oh well.
+			break
+		}
+		// Copy entry into return buffer.
+		s := struct {
+			ptr unsafe.Pointer
+			siz int
+			cap int
+		}{ptr: unsafe.Pointer(&entry), siz: reclen, cap: reclen}
+		copy(buf, *(*[]byte)(unsafe.Pointer(&s)))
+		buf = buf[reclen:]
+		n += reclen
+		cnt++
+	}
+	// Set the seek offset of the input fd to record
+	// how many files we've already returned.
+	_, err = Seek(fd, cnt, 0 /* SEEK_SET */)
+	if err != nil {
+		return n, err
+	}
+
+	return n, nil
+}
+
+// Implemented in the runtime package (runtime/sys_darwin.go)
+func syscall(fn, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno)
+func syscall6(fn, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno)
+func syscall6X(fn, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno)
+func rawSyscall(fn, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno)
+func rawSyscall6(fn, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno)
+func syscallPtr(fn, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno)
diff --git a/contrib/go/_std_1.18/src/syscall/syscall_darwin_amd64.go b/contrib/go/_std_1.19/src/syscall/syscall_darwin_amd64.go
index ef3c1998aa..ef3c1998aa 100644
--- a/contrib/go/_std_1.18/src/syscall/syscall_darwin_amd64.go
+++ b/contrib/go/_std_1.19/src/syscall/syscall_darwin_amd64.go
diff --git a/contrib/go/_std_1.19/src/syscall/syscall_linux.go b/contrib/go/_std_1.19/src/syscall/syscall_linux.go
new file mode 100644
index 0000000000..e1837b91a7
--- /dev/null
+++ b/contrib/go/_std_1.19/src/syscall/syscall_linux.go
@@ -0,0 +1,1238 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Linux system calls.
+// This file is compiled as ordinary Go code,
+// but it is also input to mksyscall,
+// which parses the //sys lines and generates system call stubs.
+// Note that sometimes we use a lowercase //sys name and
+// wrap it in our own nicer implementation.
+
+package syscall
+
+import (
+	"internal/itoa"
+	"unsafe"
+)
+
+// N.B. RawSyscall6 is provided via linkname by runtime/internal/syscall.
+//
+// Errno is uintptr and thus compatible with the runtime/internal/syscall
+// definition.
+
+func RawSyscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno)
+
+// Pull in entersyscall/exitsyscall for Syscall/Syscall6.
+//
+// Note that this can't be a push linkname because the runtime already has a
+// nameless linkname to export to assembly here and in x/sys. Additionally,
+// entersyscall fetches the caller PC and SP and thus can't have a wrapper
+// inbetween.
+
+//go:linkname runtime_entersyscall runtime.entersyscall
+func runtime_entersyscall()
+
+//go:linkname runtime_exitsyscall runtime.exitsyscall
+func runtime_exitsyscall()
+
+// N.B. For the Syscall functions below:
+//
+// //go:uintptrkeepalive because the uintptr argument may be converted pointers
+// that need to be kept alive in the caller (this is implied for RawSyscall6
+// since it has no body).
+//
+// //go:nosplit because stack copying does not account for uintptrkeepalive, so
+// the stack must not grow. Stack copying cannot blindly assume that all
+// uintptr arguments are pointers, because some values may look like pointers,
+// but not really be pointers, and adjusting their value would break the call.
+//
+// //go:norace, on RawSyscall, to avoid race instrumentation if RawSyscall is
+// called after fork, or from a signal handler.
+//
+// //go:linkname to ensure ABI wrappers are generated for external callers
+// (notably x/sys/unix assembly).
+
+//go:uintptrkeepalive
+//go:nosplit
+//go:norace
+//go:linkname RawSyscall
+func RawSyscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno) {
+	return RawSyscall6(trap, a1, a2, a3, 0, 0, 0)
+}
+
+//go:uintptrkeepalive
+//go:nosplit
+//go:linkname Syscall
+func Syscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno) {
+	runtime_entersyscall()
+	// N.B. Calling RawSyscall here is unsafe with atomic coverage
+	// instrumentation and race mode.
+	//
+	// Coverage instrumentation will add a sync/atomic call to RawSyscall.
+	// Race mode will add race instrumentation to sync/atomic. Race
+	// instrumentation requires a P, which we no longer have.
+	//
+	// RawSyscall6 is fine because it is implemented in assembly and thus
+	// has no coverage instrumentation.
+	//
+	// This is typically not a problem in the runtime because cmd/go avoids
+	// adding coverage instrumentation to the runtime in race mode.
+	r1, r2, err = RawSyscall6(trap, a1, a2, a3, 0, 0, 0)
+	runtime_exitsyscall()
+	return
+}
+
+//go:uintptrkeepalive
+//go:nosplit
+//go:linkname Syscall6
+func Syscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno) {
+	runtime_entersyscall()
+	r1, r2, err = RawSyscall6(trap, a1, a2, a3, a4, a5, a6)
+	runtime_exitsyscall()
+	return
+}
+
+func rawSyscallNoError(trap, a1, a2, a3 uintptr) (r1, r2 uintptr)
+
+/*
+ * Wrapped
+ */
+
+func Access(path string, mode uint32) (err error) {
+	return Faccessat(_AT_FDCWD, path, mode, 0)
+}
+
+func Chmod(path string, mode uint32) (err error) {
+	return Fchmodat(_AT_FDCWD, path, mode, 0)
+}
+
+func Chown(path string, uid int, gid int) (err error) {
+	return Fchownat(_AT_FDCWD, path, uid, gid, 0)
+}
+
+func Creat(path string, mode uint32) (fd int, err error) {
+	return Open(path, O_CREAT|O_WRONLY|O_TRUNC, mode)
+}
+
+func isGroupMember(gid int) bool {
+	groups, err := Getgroups()
+	if err != nil {
+		return false
+	}
+
+	for _, g := range groups {
+		if g == gid {
+			return true
+		}
+	}
+	return false
+}
+
+//sys	faccessat(dirfd int, path string, mode uint32) (err error)
+
+func Faccessat(dirfd int, path string, mode uint32, flags int) (err error) {
+	if flags & ^(_AT_SYMLINK_NOFOLLOW|_AT_EACCESS) != 0 {
+		return EINVAL
+	}
+
+	// The Linux kernel faccessat system call does not take any flags.
+	// The glibc faccessat implements the flags itself; see
+	// https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/unix/sysv/linux/faccessat.c;hb=HEAD
+	// Because people naturally expect syscall.Faccessat to act
+	// like C faccessat, we do the same.
+
+	if flags == 0 {
+		return faccessat(dirfd, path, mode)
+	}
+
+	var st Stat_t
+	if err := fstatat(dirfd, path, &st, flags&_AT_SYMLINK_NOFOLLOW); err != nil {
+		return err
+	}
+
+	mode &= 7
+	if mode == 0 {
+		return nil
+	}
+
+	var uid int
+	if flags&_AT_EACCESS != 0 {
+		uid = Geteuid()
+	} else {
+		uid = Getuid()
+	}
+
+	if uid == 0 {
+		if mode&1 == 0 {
+			// Root can read and write any file.
+			return nil
+		}
+		if st.Mode&0111 != 0 {
+			// Root can execute any file that anybody can execute.
+			return nil
+		}
+		return EACCES
+	}
+
+	var fmode uint32
+	if uint32(uid) == st.Uid {
+		fmode = (st.Mode >> 6) & 7
+	} else {
+		var gid int
+		if flags&_AT_EACCESS != 0 {
+			gid = Getegid()
+		} else {
+			gid = Getgid()
+		}
+
+		if uint32(gid) == st.Gid || isGroupMember(int(st.Gid)) {
+			fmode = (st.Mode >> 3) & 7
+		} else {
+			fmode = st.Mode & 7
+		}
+	}
+
+	if fmode&mode == mode {
+		return nil
+	}
+
+	return EACCES
+}
+
+//sys	fchmodat(dirfd int, path string, mode uint32) (err error)
+
+func Fchmodat(dirfd int, path string, mode uint32, flags int) (err error) {
+	// Linux fchmodat doesn't support the flags parameter. Mimick glibc's behavior
+	// and check the flags. Otherwise the mode would be applied to the symlink
+	// destination which is not what the user expects.
+	if flags&^_AT_SYMLINK_NOFOLLOW != 0 {
+		return EINVAL
+	} else if flags&_AT_SYMLINK_NOFOLLOW != 0 {
+		return EOPNOTSUPP
+	}
+	return fchmodat(dirfd, path, mode)
+}
+
+//sys	linkat(olddirfd int, oldpath string, newdirfd int, newpath string, flags int) (err error)
+
+func Link(oldpath string, newpath string) (err error) {
+	return linkat(_AT_FDCWD, oldpath, _AT_FDCWD, newpath, 0)
+}
+
+func Mkdir(path string, mode uint32) (err error) {
+	return Mkdirat(_AT_FDCWD, path, mode)
+}
+
+func Mknod(path string, mode uint32, dev int) (err error) {
+	return Mknodat(_AT_FDCWD, path, mode, dev)
+}
+
+func Open(path string, mode int, perm uint32) (fd int, err error) {
+	return openat(_AT_FDCWD, path, mode|O_LARGEFILE, perm)
+}
+
+//sys	openat(dirfd int, path string, flags int, mode uint32) (fd int, err error)
+
+func Openat(dirfd int, path string, flags int, mode uint32) (fd int, err error) {
+	return openat(dirfd, path, flags|O_LARGEFILE, mode)
+}
+
+func Pipe(p []int) error {
+	return Pipe2(p, 0)
+}
+
+//sysnb pipe2(p *[2]_C_int, flags int) (err error)
+
+func Pipe2(p []int, flags int) error {
+	if len(p) != 2 {
+		return EINVAL
+	}
+	var pp [2]_C_int
+	err := pipe2(&pp, flags)
+	if err == nil {
+		p[0] = int(pp[0])
+		p[1] = int(pp[1])
+	}
+	return err
+}
+
+//sys	readlinkat(dirfd int, path string, buf []byte) (n int, err error)
+
+func Readlink(path string, buf []byte) (n int, err error) {
+	return readlinkat(_AT_FDCWD, path, buf)
+}
+
+func Rename(oldpath string, newpath string) (err error) {
+	return Renameat(_AT_FDCWD, oldpath, _AT_FDCWD, newpath)
+}
+
+func Rmdir(path string) error {
+	return unlinkat(_AT_FDCWD, path, _AT_REMOVEDIR)
+}
+
+//sys	symlinkat(oldpath string, newdirfd int, newpath string) (err error)
+
+func Symlink(oldpath string, newpath string) (err error) {
+	return symlinkat(oldpath, _AT_FDCWD, newpath)
+}
+
+func Unlink(path string) error {
+	return unlinkat(_AT_FDCWD, path, 0)
+}
+
+//sys	unlinkat(dirfd int, path string, flags int) (err error)
+
+func Unlinkat(dirfd int, path string) error {
+	return unlinkat(dirfd, path, 0)
+}
+
+func Utimes(path string, tv []Timeval) (err error) {
+	if len(tv) != 2 {
+		return EINVAL
+	}
+	return utimes(path, (*[2]Timeval)(unsafe.Pointer(&tv[0])))
+}
+
+//sys	utimensat(dirfd int, path string, times *[2]Timespec, flag int) (err error)
+
+func UtimesNano(path string, ts []Timespec) (err error) {
+	if len(ts) != 2 {
+		return EINVAL
+	}
+	return utimensat(_AT_FDCWD, path, (*[2]Timespec)(unsafe.Pointer(&ts[0])), 0)
+}
+
+func Futimesat(dirfd int, path string, tv []Timeval) (err error) {
+	if len(tv) != 2 {
+		return EINVAL
+	}
+	return futimesat(dirfd, path, (*[2]Timeval)(unsafe.Pointer(&tv[0])))
+}
+
+func Futimes(fd int, tv []Timeval) (err error) {
+	// Believe it or not, this is the best we can do on Linux
+	// (and is what glibc does).
+	return Utimes("/proc/self/fd/"+itoa.Itoa(fd), tv)
+}
+
+const ImplementsGetwd = true
+
+//sys	Getcwd(buf []byte) (n int, err error)
+
+func Getwd() (wd string, err error) {
+	var buf [PathMax]byte
+	n, err := Getcwd(buf[0:])
+	if err != nil {
+		return "", err
+	}
+	// Getcwd returns the number of bytes written to buf, including the NUL.
+	if n < 1 || n > len(buf) || buf[n-1] != 0 {
+		return "", EINVAL
+	}
+	// In some cases, Linux can return a path that starts with the
+	// "(unreachable)" prefix, which can potentially be a valid relative
+	// path. To work around that, return ENOENT if path is not absolute.
+	if buf[0] != '/' {
+		return "", ENOENT
+	}
+
+	return string(buf[0 : n-1]), nil
+}
+
+func Getgroups() (gids []int, err error) {
+	n, err := getgroups(0, nil)
+	if err != nil {
+		return nil, err
+	}
+	if n == 0 {
+		return nil, nil
+	}
+
+	// Sanity check group count. Max is 1<<16 on Linux.
+	if n < 0 || n > 1<<20 {
+		return nil, EINVAL
+	}
+
+	a := make([]_Gid_t, n)
+	n, err = getgroups(n, &a[0])
+	if err != nil {
+		return nil, err
+	}
+	gids = make([]int, n)
+	for i, v := range a[0:n] {
+		gids[i] = int(v)
+	}
+	return
+}
+
+var cgo_libc_setgroups unsafe.Pointer // non-nil if cgo linked.
+
+func Setgroups(gids []int) (err error) {
+	n := uintptr(len(gids))
+	if n == 0 {
+		if cgo_libc_setgroups == nil {
+			if _, _, e1 := AllThreadsSyscall(_SYS_setgroups, 0, 0, 0); e1 != 0 {
+				err = errnoErr(e1)
+			}
+			return
+		}
+		if ret := cgocaller(cgo_libc_setgroups, 0, 0); ret != 0 {
+			err = errnoErr(Errno(ret))
+		}
+		return
+	}
+
+	a := make([]_Gid_t, len(gids))
+	for i, v := range gids {
+		a[i] = _Gid_t(v)
+	}
+	if cgo_libc_setgroups == nil {
+		if _, _, e1 := AllThreadsSyscall(_SYS_setgroups, n, uintptr(unsafe.Pointer(&a[0])), 0); e1 != 0 {
+			err = errnoErr(e1)
+		}
+		return
+	}
+	if ret := cgocaller(cgo_libc_setgroups, n, uintptr(unsafe.Pointer(&a[0]))); ret != 0 {
+		err = errnoErr(Errno(ret))
+	}
+	return
+}
+
+type WaitStatus uint32
+
+// Wait status is 7 bits at bottom, either 0 (exited),
+// 0x7F (stopped), or a signal number that caused an exit.
+// The 0x80 bit is whether there was a core dump.
+// An extra number (exit code, signal causing a stop)
+// is in the high bits. At least that's the idea.
+// There are various irregularities. For example, the
+// "continued" status is 0xFFFF, distinguishing itself
+// from stopped via the core dump bit.
+
+const (
+	mask    = 0x7F
+	core    = 0x80
+	exited  = 0x00
+	stopped = 0x7F
+	shift   = 8
+)
+
+func (w WaitStatus) Exited() bool { return w&mask == exited }
+
+func (w WaitStatus) Signaled() bool { return w&mask != stopped && w&mask != exited }
+
+func (w WaitStatus) Stopped() bool { return w&0xFF == stopped }
+
+func (w WaitStatus) Continued() bool { return w == 0xFFFF }
+
+func (w WaitStatus) CoreDump() bool { return w.Signaled() && w&core != 0 }
+
+func (w WaitStatus) ExitStatus() int {
+	if !w.Exited() {
+		return -1
+	}
+	return int(w>>shift) & 0xFF
+}
+
+func (w WaitStatus) Signal() Signal {
+	if !w.Signaled() {
+		return -1
+	}
+	return Signal(w & mask)
+}
+
+func (w WaitStatus) StopSignal() Signal {
+	if !w.Stopped() {
+		return -1
+	}
+	return Signal(w>>shift) & 0xFF
+}
+
+func (w WaitStatus) TrapCause() int {
+	if w.StopSignal() != SIGTRAP {
+		return -1
+	}
+	return int(w>>shift) >> 8
+}
+
+//sys	wait4(pid int, wstatus *_C_int, options int, rusage *Rusage) (wpid int, err error)
+
+func Wait4(pid int, wstatus *WaitStatus, options int, rusage *Rusage) (wpid int, err error) {
+	var status _C_int
+	wpid, err = wait4(pid, &status, options, rusage)
+	if wstatus != nil {
+		*wstatus = WaitStatus(status)
+	}
+	return
+}
+
+func Mkfifo(path string, mode uint32) (err error) {
+	return Mknod(path, mode|S_IFIFO, 0)
+}
+
+func (sa *SockaddrInet4) sockaddr() (unsafe.Pointer, _Socklen, error) {
+	if sa.Port < 0 || sa.Port > 0xFFFF {
+		return nil, 0, EINVAL
+	}
+	sa.raw.Family = AF_INET
+	p := (*[2]byte)(unsafe.Pointer(&sa.raw.Port))
+	p[0] = byte(sa.Port >> 8)
+	p[1] = byte(sa.Port)
+	sa.raw.Addr = sa.Addr
+	return unsafe.Pointer(&sa.raw), SizeofSockaddrInet4, nil
+}
+
+func (sa *SockaddrInet6) sockaddr() (unsafe.Pointer, _Socklen, error) {
+	if sa.Port < 0 || sa.Port > 0xFFFF {
+		return nil, 0, EINVAL
+	}
+	sa.raw.Family = AF_INET6
+	p := (*[2]byte)(unsafe.Pointer(&sa.raw.Port))
+	p[0] = byte(sa.Port >> 8)
+	p[1] = byte(sa.Port)
+	sa.raw.Scope_id = sa.ZoneId
+	sa.raw.Addr = sa.Addr
+	return unsafe.Pointer(&sa.raw), SizeofSockaddrInet6, nil
+}
+
+func (sa *SockaddrUnix) sockaddr() (unsafe.Pointer, _Socklen, error) {
+	name := sa.Name
+	n := len(name)
+	if n > len(sa.raw.Path) {
+		return nil, 0, EINVAL
+	}
+	if n == len(sa.raw.Path) && name[0] != '@' {
+		return nil, 0, EINVAL
+	}
+	sa.raw.Family = AF_UNIX
+	for i := 0; i < n; i++ {
+		sa.raw.Path[i] = int8(name[i])
+	}
+	// length is family (uint16), name, NUL.
+	sl := _Socklen(2)
+	if n > 0 {
+		sl += _Socklen(n) + 1
+	}
+	if sa.raw.Path[0] == '@' {
+		sa.raw.Path[0] = 0
+		// Don't count trailing NUL for abstract address.
+		sl--
+	}
+
+	return unsafe.Pointer(&sa.raw), sl, nil
+}
+
+type SockaddrLinklayer struct {
+	Protocol uint16
+	Ifindex  int
+	Hatype   uint16
+	Pkttype  uint8
+	Halen    uint8
+	Addr     [8]byte
+	raw      RawSockaddrLinklayer
+}
+
+func (sa *SockaddrLinklayer) sockaddr() (unsafe.Pointer, _Socklen, error) {
+	if sa.Ifindex < 0 || sa.Ifindex > 0x7fffffff {
+		return nil, 0, EINVAL
+	}
+	sa.raw.Family = AF_PACKET
+	sa.raw.Protocol = sa.Protocol
+	sa.raw.Ifindex = int32(sa.Ifindex)
+	sa.raw.Hatype = sa.Hatype
+	sa.raw.Pkttype = sa.Pkttype
+	sa.raw.Halen = sa.Halen
+	sa.raw.Addr = sa.Addr
+	return unsafe.Pointer(&sa.raw), SizeofSockaddrLinklayer, nil
+}
+
+type SockaddrNetlink struct {
+	Family uint16
+	Pad    uint16
+	Pid    uint32
+	Groups uint32
+	raw    RawSockaddrNetlink
+}
+
+func (sa *SockaddrNetlink) sockaddr() (unsafe.Pointer, _Socklen, error) {
+	sa.raw.Family = AF_NETLINK
+	sa.raw.Pad = sa.Pad
+	sa.raw.Pid = sa.Pid
+	sa.raw.Groups = sa.Groups
+	return unsafe.Pointer(&sa.raw), SizeofSockaddrNetlink, nil
+}
+
+func anyToSockaddr(rsa *RawSockaddrAny) (Sockaddr, error) {
+	switch rsa.Addr.Family {
+	case AF_NETLINK:
+		pp := (*RawSockaddrNetlink)(unsafe.Pointer(rsa))
+		sa := new(SockaddrNetlink)
+		sa.Family = pp.Family
+		sa.Pad = pp.Pad
+		sa.Pid = pp.Pid
+		sa.Groups = pp.Groups
+		return sa, nil
+
+	case AF_PACKET:
+		pp := (*RawSockaddrLinklayer)(unsafe.Pointer(rsa))
+		sa := new(SockaddrLinklayer)
+		sa.Protocol = pp.Protocol
+		sa.Ifindex = int(pp.Ifindex)
+		sa.Hatype = pp.Hatype
+		sa.Pkttype = pp.Pkttype
+		sa.Halen = pp.Halen
+		sa.Addr = pp.Addr
+		return sa, nil
+
+	case AF_UNIX:
+		pp := (*RawSockaddrUnix)(unsafe.Pointer(rsa))
+		sa := new(SockaddrUnix)
+		if pp.Path[0] == 0 {
+			// "Abstract" Unix domain socket.
+			// Rewrite leading NUL as @ for textual display.
+			// (This is the standard convention.)
+			// Not friendly to overwrite in place,
+			// but the callers below don't care.
+			pp.Path[0] = '@'
+		}
+
+		// Assume path ends at NUL.
+		// This is not technically the Linux semantics for
+		// abstract Unix domain sockets--they are supposed
+		// to be uninterpreted fixed-size binary blobs--but
+		// everyone uses this convention.
+		n := 0
+		for n < len(pp.Path) && pp.Path[n] != 0 {
+			n++
+		}
+		bytes := (*[len(pp.Path)]byte)(unsafe.Pointer(&pp.Path[0]))[0:n]
+		sa.Name = string(bytes)
+		return sa, nil
+
+	case AF_INET:
+		pp := (*RawSockaddrInet4)(unsafe.Pointer(rsa))
+		sa := new(SockaddrInet4)
+		p := (*[2]byte)(unsafe.Pointer(&pp.Port))
+		sa.Port = int(p[0])<<8 + int(p[1])
+		sa.Addr = pp.Addr
+		return sa, nil
+
+	case AF_INET6:
+		pp := (*RawSockaddrInet6)(unsafe.Pointer(rsa))
+		sa := new(SockaddrInet6)
+		p := (*[2]byte)(unsafe.Pointer(&pp.Port))
+		sa.Port = int(p[0])<<8 + int(p[1])
+		sa.ZoneId = pp.Scope_id
+		sa.Addr = pp.Addr
+		return sa, nil
+	}
+	return nil, EAFNOSUPPORT
+}
+
+func Accept(fd int) (nfd int, sa Sockaddr, err error) {
+	var rsa RawSockaddrAny
+	var len _Socklen = SizeofSockaddrAny
+	nfd, err = accept4(fd, &rsa, &len, 0)
+	if err != nil {
+		return
+	}
+	sa, err = anyToSockaddr(&rsa)
+	if err != nil {
+		Close(nfd)
+		nfd = 0
+	}
+	return
+}
+
+func Accept4(fd int, flags int) (nfd int, sa Sockaddr, err error) {
+	var rsa RawSockaddrAny
+	var len _Socklen = SizeofSockaddrAny
+	nfd, err = accept4(fd, &rsa, &len, flags)
+	if err != nil {
+		return
+	}
+	if len > SizeofSockaddrAny {
+		panic("RawSockaddrAny too small")
+	}
+	sa, err = anyToSockaddr(&rsa)
+	if err != nil {
+		Close(nfd)
+		nfd = 0
+	}
+	return
+}
+
+func Getsockname(fd int) (sa Sockaddr, err error) {
+	var rsa RawSockaddrAny
+	var len _Socklen = SizeofSockaddrAny
+	if err = getsockname(fd, &rsa, &len); err != nil {
+		return
+	}
+	return anyToSockaddr(&rsa)
+}
+
+func GetsockoptInet4Addr(fd, level, opt int) (value [4]byte, err error) {
+	vallen := _Socklen(4)
+	err = getsockopt(fd, level, opt, unsafe.Pointer(&value[0]), &vallen)
+	return value, err
+}
+
+func GetsockoptIPMreq(fd, level, opt int) (*IPMreq, error) {
+	var value IPMreq
+	vallen := _Socklen(SizeofIPMreq)
+	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
+	return &value, err
+}
+
+func GetsockoptIPMreqn(fd, level, opt int) (*IPMreqn, error) {
+	var value IPMreqn
+	vallen := _Socklen(SizeofIPMreqn)
+	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
+	return &value, err
+}
+
+func GetsockoptIPv6Mreq(fd, level, opt int) (*IPv6Mreq, error) {
+	var value IPv6Mreq
+	vallen := _Socklen(SizeofIPv6Mreq)
+	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
+	return &value, err
+}
+
+func GetsockoptIPv6MTUInfo(fd, level, opt int) (*IPv6MTUInfo, error) {
+	var value IPv6MTUInfo
+	vallen := _Socklen(SizeofIPv6MTUInfo)
+	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
+	return &value, err
+}
+
+func GetsockoptICMPv6Filter(fd, level, opt int) (*ICMPv6Filter, error) {
+	var value ICMPv6Filter
+	vallen := _Socklen(SizeofICMPv6Filter)
+	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
+	return &value, err
+}
+
+func GetsockoptUcred(fd, level, opt int) (*Ucred, error) {
+	var value Ucred
+	vallen := _Socklen(SizeofUcred)
+	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
+	return &value, err
+}
+
+func SetsockoptIPMreqn(fd, level, opt int, mreq *IPMreqn) (err error) {
+	return setsockopt(fd, level, opt, unsafe.Pointer(mreq), unsafe.Sizeof(*mreq))
+}
+
+func recvmsgRaw(fd int, p, oob []byte, flags int, rsa *RawSockaddrAny) (n, oobn int, recvflags int, err error) {
+	var msg Msghdr
+	msg.Name = (*byte)(unsafe.Pointer(rsa))
+	msg.Namelen = uint32(SizeofSockaddrAny)
+	var iov Iovec
+	if len(p) > 0 {
+		iov.Base = &p[0]
+		iov.SetLen(len(p))
+	}
+	var dummy byte
+	if len(oob) > 0 {
+		if len(p) == 0 {
+			var sockType int
+			sockType, err = GetsockoptInt(fd, SOL_SOCKET, SO_TYPE)
+			if err != nil {
+				return
+			}
+			// receive at least one normal byte
+			if sockType != SOCK_DGRAM {
+				iov.Base = &dummy
+				iov.SetLen(1)
+			}
+		}
+		msg.Control = &oob[0]
+		msg.SetControllen(len(oob))
+	}
+	msg.Iov = &iov
+	msg.Iovlen = 1
+	if n, err = recvmsg(fd, &msg, flags); err != nil {
+		return
+	}
+	oobn = int(msg.Controllen)
+	recvflags = int(msg.Flags)
+	return
+}
+
+func sendmsgN(fd int, p, oob []byte, ptr unsafe.Pointer, salen _Socklen, flags int) (n int, err error) {
+	var msg Msghdr
+	msg.Name = (*byte)(ptr)
+	msg.Namelen = uint32(salen)
+	var iov Iovec
+	if len(p) > 0 {
+		iov.Base = &p[0]
+		iov.SetLen(len(p))
+	}
+	var dummy byte
+	if len(oob) > 0 {
+		if len(p) == 0 {
+			var sockType int
+			sockType, err = GetsockoptInt(fd, SOL_SOCKET, SO_TYPE)
+			if err != nil {
+				return 0, err
+			}
+			// send at least one normal byte
+			if sockType != SOCK_DGRAM {
+				iov.Base = &dummy
+				iov.SetLen(1)
+			}
+		}
+		msg.Control = &oob[0]
+		msg.SetControllen(len(oob))
+	}
+	msg.Iov = &iov
+	msg.Iovlen = 1
+	if n, err = sendmsg(fd, &msg, flags); err != nil {
+		return 0, err
+	}
+	if len(oob) > 0 && len(p) == 0 {
+		n = 0
+	}
+	return n, nil
+}
+
+// BindToDevice binds the socket associated with fd to device.
+func BindToDevice(fd int, device string) (err error) {
+	return SetsockoptString(fd, SOL_SOCKET, SO_BINDTODEVICE, device)
+}
+
+//sys	ptrace(request int, pid int, addr uintptr, data uintptr) (err error)
+
+func ptracePeek(req int, pid int, addr uintptr, out []byte) (count int, err error) {
+	// The peek requests are machine-size oriented, so we wrap it
+	// to retrieve arbitrary-length data.
+
+	// The ptrace syscall differs from glibc's ptrace.
+	// Peeks returns the word in *data, not as the return value.
+
+	var buf [sizeofPtr]byte
+
+	// Leading edge. PEEKTEXT/PEEKDATA don't require aligned
+	// access (PEEKUSER warns that it might), but if we don't
+	// align our reads, we might straddle an unmapped page
+	// boundary and not get the bytes leading up to the page
+	// boundary.
+	n := 0
+	if addr%sizeofPtr != 0 {
+		err = ptrace(req, pid, addr-addr%sizeofPtr, uintptr(unsafe.Pointer(&buf[0])))
+		if err != nil {
+			return 0, err
+		}
+		n += copy(out, buf[addr%sizeofPtr:])
+		out = out[n:]
+	}
+
+	// Remainder.
+	for len(out) > 0 {
+		// We use an internal buffer to guarantee alignment.
+		// It's not documented if this is necessary, but we're paranoid.
+		err = ptrace(req, pid, addr+uintptr(n), uintptr(unsafe.Pointer(&buf[0])))
+		if err != nil {
+			return n, err
+		}
+		copied := copy(out, buf[0:])
+		n += copied
+		out = out[copied:]
+	}
+
+	return n, nil
+}
+
+func PtracePeekText(pid int, addr uintptr, out []byte) (count int, err error) {
+	return ptracePeek(PTRACE_PEEKTEXT, pid, addr, out)
+}
+
+func PtracePeekData(pid int, addr uintptr, out []byte) (count int, err error) {
+	return ptracePeek(PTRACE_PEEKDATA, pid, addr, out)
+}
+
+func ptracePoke(pokeReq int, peekReq int, pid int, addr uintptr, data []byte) (count int, err error) {
+	// As for ptracePeek, we need to align our accesses to deal
+	// with the possibility of straddling an invalid page.
+
+	// Leading edge.
+	n := 0
+	if addr%sizeofPtr != 0 {
+		var buf [sizeofPtr]byte
+		err = ptrace(peekReq, pid, addr-addr%sizeofPtr, uintptr(unsafe.Pointer(&buf[0])))
+		if err != nil {
+			return 0, err
+		}
+		n += copy(buf[addr%sizeofPtr:], data)
+		word := *((*uintptr)(unsafe.Pointer(&buf[0])))
+		err = ptrace(pokeReq, pid, addr-addr%sizeofPtr, word)
+		if err != nil {
+			return 0, err
+		}
+		data = data[n:]
+	}
+
+	// Interior.
+	for len(data) > sizeofPtr {
+		word := *((*uintptr)(unsafe.Pointer(&data[0])))
+		err = ptrace(pokeReq, pid, addr+uintptr(n), word)
+		if err != nil {
+			return n, err
+		}
+		n += sizeofPtr
+		data = data[sizeofPtr:]
+	}
+
+	// Trailing edge.
+	if len(data) > 0 {
+		var buf [sizeofPtr]byte
+		err = ptrace(peekReq, pid, addr+uintptr(n), uintptr(unsafe.Pointer(&buf[0])))
+		if err != nil {
+			return n, err
+		}
+		copy(buf[0:], data)
+		word := *((*uintptr)(unsafe.Pointer(&buf[0])))
+		err = ptrace(pokeReq, pid, addr+uintptr(n), word)
+		if err != nil {
+			return n, err
+		}
+		n += len(data)
+	}
+
+	return n, nil
+}
+
+func PtracePokeText(pid int, addr uintptr, data []byte) (count int, err error) {
+	return ptracePoke(PTRACE_POKETEXT, PTRACE_PEEKTEXT, pid, addr, data)
+}
+
+func PtracePokeData(pid int, addr uintptr, data []byte) (count int, err error) {
+	return ptracePoke(PTRACE_POKEDATA, PTRACE_PEEKDATA, pid, addr, data)
+}
+
+func PtraceGetRegs(pid int, regsout *PtraceRegs) (err error) {
+	return ptrace(PTRACE_GETREGS, pid, 0, uintptr(unsafe.Pointer(regsout)))
+}
+
+func PtraceSetRegs(pid int, regs *PtraceRegs) (err error) {
+	return ptrace(PTRACE_SETREGS, pid, 0, uintptr(unsafe.Pointer(regs)))
+}
+
+func PtraceSetOptions(pid int, options int) (err error) {
+	return ptrace(PTRACE_SETOPTIONS, pid, 0, uintptr(options))
+}
+
+func PtraceGetEventMsg(pid int) (msg uint, err error) {
+	var data _C_long
+	err = ptrace(PTRACE_GETEVENTMSG, pid, 0, uintptr(unsafe.Pointer(&data)))
+	msg = uint(data)
+	return
+}
+
+func PtraceCont(pid int, signal int) (err error) {
+	return ptrace(PTRACE_CONT, pid, 0, uintptr(signal))
+}
+
+func PtraceSyscall(pid int, signal int) (err error) {
+	return ptrace(PTRACE_SYSCALL, pid, 0, uintptr(signal))
+}
+
+func PtraceSingleStep(pid int) (err error) { return ptrace(PTRACE_SINGLESTEP, pid, 0, 0) }
+
+func PtraceAttach(pid int) (err error) { return ptrace(PTRACE_ATTACH, pid, 0, 0) }
+
+func PtraceDetach(pid int) (err error) { return ptrace(PTRACE_DETACH, pid, 0, 0) }
+
+//sys	reboot(magic1 uint, magic2 uint, cmd int, arg string) (err error)
+
+func Reboot(cmd int) (err error) {
+	return reboot(LINUX_REBOOT_MAGIC1, LINUX_REBOOT_MAGIC2, cmd, "")
+}
+
+func ReadDirent(fd int, buf []byte) (n int, err error) {
+	return Getdents(fd, buf)
+}
+
+func direntIno(buf []byte) (uint64, bool) {
+	return readInt(buf, unsafe.Offsetof(Dirent{}.Ino), unsafe.Sizeof(Dirent{}.Ino))
+}
+
+func direntReclen(buf []byte) (uint64, bool) {
+	return readInt(buf, unsafe.Offsetof(Dirent{}.Reclen), unsafe.Sizeof(Dirent{}.Reclen))
+}
+
+func direntNamlen(buf []byte) (uint64, bool) {
+	reclen, ok := direntReclen(buf)
+	if !ok {
+		return 0, false
+	}
+	return reclen - uint64(unsafe.Offsetof(Dirent{}.Name)), true
+}
+
+//sys	mount(source string, target string, fstype string, flags uintptr, data *byte) (err error)
+
+func Mount(source string, target string, fstype string, flags uintptr, data string) (err error) {
+	// Certain file systems get rather angry and EINVAL if you give
+	// them an empty string of data, rather than NULL.
+	if data == "" {
+		return mount(source, target, fstype, flags, nil)
+	}
+	datap, err := BytePtrFromString(data)
+	if err != nil {
+		return err
+	}
+	return mount(source, target, fstype, flags, datap)
+}
+
+// Sendto
+// Recvfrom
+// Socketpair
+
+/*
+ * Direct access
+ */
+//sys	Acct(path string) (err error)
+//sys	Adjtimex(buf *Timex) (state int, err error)
+//sys	Chdir(path string) (err error)
+//sys	Chroot(path string) (err error)
+//sys	Close(fd int) (err error)
+//sys	Dup(oldfd int) (fd int, err error)
+//sys	Dup3(oldfd int, newfd int, flags int) (err error)
+//sysnb	EpollCreate1(flag int) (fd int, err error)
+//sysnb	EpollCtl(epfd int, op int, fd int, event *EpollEvent) (err error)
+//sys	Fallocate(fd int, mode uint32, off int64, len int64) (err error)
+//sys	Fchdir(fd int) (err error)
+//sys	Fchmod(fd int, mode uint32) (err error)
+//sys	Fchownat(dirfd int, path string, uid int, gid int, flags int) (err error)
+//sys	fcntl(fd int, cmd int, arg int) (val int, err error)
+//sys	Fdatasync(fd int) (err error)
+//sys	Flock(fd int, how int) (err error)
+//sys	Fsync(fd int) (err error)
+//sys	Getdents(fd int, buf []byte) (n int, err error) = SYS_GETDENTS64
+//sysnb	Getpgid(pid int) (pgid int, err error)
+
+func Getpgrp() (pid int) {
+	pid, _ = Getpgid(0)
+	return
+}
+
+//sysnb	Getpid() (pid int)
+//sysnb	Getppid() (ppid int)
+//sys	Getpriority(which int, who int) (prio int, err error)
+//sysnb	Getrusage(who int, rusage *Rusage) (err error)
+//sysnb	Gettid() (tid int)
+//sys	Getxattr(path string, attr string, dest []byte) (sz int, err error)
+//sys	InotifyAddWatch(fd int, pathname string, mask uint32) (watchdesc int, err error)
+//sysnb	InotifyInit1(flags int) (fd int, err error)
+//sysnb	InotifyRmWatch(fd int, watchdesc uint32) (success int, err error)
+//sysnb	Kill(pid int, sig Signal) (err error)
+//sys	Klogctl(typ int, buf []byte) (n int, err error) = SYS_SYSLOG
+//sys	Listxattr(path string, dest []byte) (sz int, err error)
+//sys	Mkdirat(dirfd int, path string, mode uint32) (err error)
+//sys	Mknodat(dirfd int, path string, mode uint32, dev int) (err error)
+//sys	Nanosleep(time *Timespec, leftover *Timespec) (err error)
+//sys	PivotRoot(newroot string, putold string) (err error) = SYS_PIVOT_ROOT
+//sysnb prlimit(pid int, resource int, newlimit *Rlimit, old *Rlimit) (err error) = SYS_PRLIMIT64
+//sys	read(fd int, p []byte) (n int, err error)
+//sys	Removexattr(path string, attr string) (err error)
+//sys	Setdomainname(p []byte) (err error)
+//sys	Sethostname(p []byte) (err error)
+//sysnb	Setpgid(pid int, pgid int) (err error)
+//sysnb	Setsid() (pid int, err error)
+//sysnb	Settimeofday(tv *Timeval) (err error)
+
+// Provided by runtime.syscall_runtime_doAllThreadsSyscall which stops the
+// world and invokes the syscall on each OS thread. Once this function returns,
+// all threads are in sync.
+//
+//go:uintptrescapes
+func runtime_doAllThreadsSyscall(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr)
+
+// AllThreadsSyscall performs a syscall on each OS thread of the Go
+// runtime. It first invokes the syscall on one thread. Should that
+// invocation fail, it returns immediately with the error status.
+// Otherwise, it invokes the syscall on all of the remaining threads
+// in parallel. It will terminate the program if it observes any
+// invoked syscall's return value differs from that of the first
+// invocation.
+//
+// AllThreadsSyscall is intended for emulating simultaneous
+// process-wide state changes that require consistently modifying
+// per-thread state of the Go runtime.
+//
+// AllThreadsSyscall is unaware of any threads that are launched
+// explicitly by cgo linked code, so the function always returns
+// ENOTSUP in binaries that use cgo.
+//
+//go:uintptrescapes
+func AllThreadsSyscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno) {
+	if cgo_libc_setegid != nil {
+		return minus1, minus1, ENOTSUP
+	}
+	r1, r2, errno := runtime_doAllThreadsSyscall(trap, a1, a2, a3, 0, 0, 0)
+	return r1, r2, Errno(errno)
+}
+
+// AllThreadsSyscall6 is like AllThreadsSyscall, but extended to six
+// arguments.
+//
+//go:uintptrescapes
+func AllThreadsSyscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno) {
+	if cgo_libc_setegid != nil {
+		return minus1, minus1, ENOTSUP
+	}
+	r1, r2, errno := runtime_doAllThreadsSyscall(trap, a1, a2, a3, a4, a5, a6)
+	return r1, r2, Errno(errno)
+}
+
+// linked by runtime.cgocall.go
+//
+//go:uintptrescapes
+func cgocaller(unsafe.Pointer, ...uintptr) uintptr
+
+var cgo_libc_setegid unsafe.Pointer // non-nil if cgo linked.
+
+const minus1 = ^uintptr(0)
+
+func Setegid(egid int) (err error) {
+	if cgo_libc_setegid == nil {
+		if _, _, e1 := AllThreadsSyscall(SYS_SETRESGID, minus1, uintptr(egid), minus1); e1 != 0 {
+			err = errnoErr(e1)
+		}
+	} else if ret := cgocaller(cgo_libc_setegid, uintptr(egid)); ret != 0 {
+		err = errnoErr(Errno(ret))
+	}
+	return
+}
+
+var cgo_libc_seteuid unsafe.Pointer // non-nil if cgo linked.
+
+func Seteuid(euid int) (err error) {
+	if cgo_libc_seteuid == nil {
+		if _, _, e1 := AllThreadsSyscall(SYS_SETRESUID, minus1, uintptr(euid), minus1); e1 != 0 {
+			err = errnoErr(e1)
+		}
+	} else if ret := cgocaller(cgo_libc_seteuid, uintptr(euid)); ret != 0 {
+		err = errnoErr(Errno(ret))
+	}
+	return
+}
+
+var cgo_libc_setgid unsafe.Pointer // non-nil if cgo linked.
+
+func Setgid(gid int) (err error) {
+	if cgo_libc_setgid == nil {
+		if _, _, e1 := AllThreadsSyscall(sys_SETGID, uintptr(gid), 0, 0); e1 != 0 {
+			err = errnoErr(e1)
+		}
+	} else if ret := cgocaller(cgo_libc_setgid, uintptr(gid)); ret != 0 {
+		err = errnoErr(Errno(ret))
+	}
+	return
+}
+
+var cgo_libc_setregid unsafe.Pointer // non-nil if cgo linked.
+
+func Setregid(rgid, egid int) (err error) {
+	if cgo_libc_setregid == nil {
+		if _, _, e1 := AllThreadsSyscall(sys_SETREGID, uintptr(rgid), uintptr(egid), 0); e1 != 0 {
+			err = errnoErr(e1)
+		}
+	} else if ret := cgocaller(cgo_libc_setregid, uintptr(rgid), uintptr(egid)); ret != 0 {
+		err = errnoErr(Errno(ret))
+	}
+	return
+}
+
+var cgo_libc_setresgid unsafe.Pointer // non-nil if cgo linked.
+
+func Setresgid(rgid, egid, sgid int) (err error) {
+	if cgo_libc_setresgid == nil {
+		if _, _, e1 := AllThreadsSyscall(sys_SETRESGID, uintptr(rgid), uintptr(egid), uintptr(sgid)); e1 != 0 {
+			err = errnoErr(e1)
+		}
+	} else if ret := cgocaller(cgo_libc_setresgid, uintptr(rgid), uintptr(egid), uintptr(sgid)); ret != 0 {
+		err = errnoErr(Errno(ret))
+	}
+	return
+}
+
+var cgo_libc_setresuid unsafe.Pointer // non-nil if cgo linked.
+
+func Setresuid(ruid, euid, suid int) (err error) {
+	if cgo_libc_setresuid == nil {
+		if _, _, e1 := AllThreadsSyscall(sys_SETRESUID, uintptr(ruid), uintptr(euid), uintptr(suid)); e1 != 0 {
+			err = errnoErr(e1)
+		}
+	} else if ret := cgocaller(cgo_libc_setresuid, uintptr(ruid), uintptr(euid), uintptr(suid)); ret != 0 {
+		err = errnoErr(Errno(ret))
+	}
+	return
+}
+
+var cgo_libc_setreuid unsafe.Pointer // non-nil if cgo linked.
+
+func Setreuid(ruid, euid int) (err error) {
+	if cgo_libc_setreuid == nil {
+		if _, _, e1 := AllThreadsSyscall(sys_SETREUID, uintptr(ruid), uintptr(euid), 0); e1 != 0 {
+			err = errnoErr(e1)
+		}
+	} else if ret := cgocaller(cgo_libc_setreuid, uintptr(ruid), uintptr(euid)); ret != 0 {
+		err = errnoErr(Errno(ret))
+	}
+	return
+}
+
+var cgo_libc_setuid unsafe.Pointer // non-nil if cgo linked.
+
+func Setuid(uid int) (err error) {
+	if cgo_libc_setuid == nil {
+		if _, _, e1 := AllThreadsSyscall(sys_SETUID, uintptr(uid), 0, 0); e1 != 0 {
+			err = errnoErr(e1)
+		}
+	} else if ret := cgocaller(cgo_libc_setuid, uintptr(uid)); ret != 0 {
+		err = errnoErr(Errno(ret))
+	}
+	return
+}
+
+//sys	Setpriority(which int, who int, prio int) (err error)
+//sys	Setxattr(path string, attr string, data []byte, flags int) (err error)
+//sys	Sync()
+//sysnb	Sysinfo(info *Sysinfo_t) (err error)
+//sys	Tee(rfd int, wfd int, len int, flags int) (n int64, err error)
+//sysnb	Tgkill(tgid int, tid int, sig Signal) (err error)
+//sysnb	Times(tms *Tms) (ticks uintptr, err error)
+//sysnb	Umask(mask int) (oldmask int)
+//sysnb	Uname(buf *Utsname) (err error)
+//sys	Unmount(target string, flags int) (err error) = SYS_UMOUNT2
+//sys	Unshare(flags int) (err error)
+//sys	write(fd int, p []byte) (n int, err error)
+//sys	exitThread(code int) (err error) = SYS_EXIT
+//sys	readlen(fd int, p *byte, np int) (n int, err error) = SYS_READ
+//sys	writelen(fd int, p *byte, np int) (n int, err error) = SYS_WRITE
+
+// mmap varies by architecture; see syscall_linux_*.go.
+//sys	munmap(addr uintptr, length uintptr) (err error)
+
+var mapper = &mmapper{
+	active: make(map[*byte][]byte),
+	mmap:   mmap,
+	munmap: munmap,
+}
+
+func Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error) {
+	return mapper.Mmap(fd, offset, length, prot, flags)
+}
+
+func Munmap(b []byte) (err error) {
+	return mapper.Munmap(b)
+}
+
+//sys	Madvise(b []byte, advice int) (err error)
+//sys	Mprotect(b []byte, prot int) (err error)
+//sys	Mlock(b []byte) (err error)
+//sys	Munlock(b []byte) (err error)
+//sys	Mlockall(flags int) (err error)
+//sys	Munlockall() (err error)
diff --git a/contrib/go/_std_1.19/src/syscall/syscall_linux_amd64.go b/contrib/go/_std_1.19/src/syscall/syscall_linux_amd64.go
new file mode 100644
index 0000000000..0bcc664d32
--- /dev/null
+++ b/contrib/go/_std_1.19/src/syscall/syscall_linux_amd64.go
@@ -0,0 +1,122 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package syscall
+
+const _SYS_setgroups = SYS_SETGROUPS
+
+//sys	Dup2(oldfd int, newfd int) (err error)
+//sysnb	EpollCreate(size int) (fd int, err error)
+//sys	Fchown(fd int, uid int, gid int) (err error)
+//sys	Fstat(fd int, stat *Stat_t) (err error)
+//sys	Fstatfs(fd int, buf *Statfs_t) (err error)
+//sys	Ftruncate(fd int, length int64) (err error)
+//sysnb	Getegid() (egid int)
+//sysnb	Geteuid() (euid int)
+//sysnb	Getgid() (gid int)
+//sysnb	Getrlimit(resource int, rlim *Rlimit) (err error)
+//sysnb	Getuid() (uid int)
+//sysnb	InotifyInit() (fd int, err error)
+//sys	Ioperm(from int, num int, on int) (err error)
+//sys	Iopl(level int) (err error)
+//sys	Listen(s int, n int) (err error)
+//sys	Pause() (err error)
+//sys	pread(fd int, p []byte, offset int64) (n int, err error) = SYS_PREAD64
+//sys	pwrite(fd int, p []byte, offset int64) (n int, err error) = SYS_PWRITE64
+//sys	Renameat(olddirfd int, oldpath string, newdirfd int, newpath string) (err error)
+//sys	Seek(fd int, offset int64, whence int) (off int64, err error) = SYS_LSEEK
+//sys	Select(nfd int, r *FdSet, w *FdSet, e *FdSet, timeout *Timeval) (n int, err error)
+//sys	sendfile(outfd int, infd int, offset *int64, count int) (written int, err error)
+//sys	Setfsgid(gid int) (err error)
+//sys	Setfsuid(uid int) (err error)
+//sysnb	Setrlimit(resource int, rlim *Rlimit) (err error)
+//sys	Shutdown(fd int, how int) (err error)
+//sys	Splice(rfd int, roff *int64, wfd int, woff *int64, len int, flags int) (n int64, err error)
+//sys	Statfs(path string, buf *Statfs_t) (err error)
+//sys	SyncFileRange(fd int, off int64, n int64, flags int) (err error)
+//sys	Truncate(path string, length int64) (err error)
+//sys	Ustat(dev int, ubuf *Ustat_t) (err error)
+//sys	accept4(s int, rsa *RawSockaddrAny, addrlen *_Socklen, flags int) (fd int, err error)
+//sys	bind(s int, addr unsafe.Pointer, addrlen _Socklen) (err error)
+//sys	connect(s int, addr unsafe.Pointer, addrlen _Socklen) (err error)
+//sys	fstatat(fd int, path string, stat *Stat_t, flags int) (err error) = SYS_NEWFSTATAT
+//sysnb	getgroups(n int, list *_Gid_t) (nn int, err error)
+//sys	getsockopt(s int, level int, name int, val unsafe.Pointer, vallen *_Socklen) (err error)
+//sys	setsockopt(s int, level int, name int, val unsafe.Pointer, vallen uintptr) (err error)
+//sysnb	socket(domain int, typ int, proto int) (fd int, err error)
+//sysnb	socketpair(domain int, typ int, proto int, fd *[2]int32) (err error)
+//sysnb	getpeername(fd int, rsa *RawSockaddrAny, addrlen *_Socklen) (err error)
+//sysnb	getsockname(fd int, rsa *RawSockaddrAny, addrlen *_Socklen) (err error)
+//sys	recvfrom(fd int, p []byte, flags int, from *RawSockaddrAny, fromlen *_Socklen) (n int, err error)
+//sys	sendto(s int, buf []byte, flags int, to unsafe.Pointer, addrlen _Socklen) (err error)
+//sys	recvmsg(s int, msg *Msghdr, flags int) (n int, err error)
+//sys	sendmsg(s int, msg *Msghdr, flags int) (n int, err error)
+//sys	mmap(addr uintptr, length uintptr, prot int, flags int, fd int, offset int64) (xaddr uintptr, err error)
+//sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
+
+func Stat(path string, stat *Stat_t) (err error) {
+	return fstatat(_AT_FDCWD, path, stat, 0)
+}
+
+func Lchown(path string, uid int, gid int) (err error) {
+	return Fchownat(_AT_FDCWD, path, uid, gid, _AT_SYMLINK_NOFOLLOW)
+}
+
+func Lstat(path string, stat *Stat_t) (err error) {
+	return fstatat(_AT_FDCWD, path, stat, _AT_SYMLINK_NOFOLLOW)
+}
+
+//sys	futimesat(dirfd int, path string, times *[2]Timeval) (err error)
+
+//go:noescape
+func gettimeofday(tv *Timeval) (err Errno)
+
+func Gettimeofday(tv *Timeval) (err error) {
+	errno := gettimeofday(tv)
+	if errno != 0 {
+		return errno
+	}
+	return nil
+}
+
+func Time(t *Time_t) (tt Time_t, err error) {
+	var tv Timeval
+	errno := gettimeofday(&tv)
+	if errno != 0 {
+		return 0, errno
+	}
+	if t != nil {
+		*t = Time_t(tv.Sec)
+	}
+	return Time_t(tv.Sec), nil
+}
+
+//sys	Utime(path string, buf *Utimbuf) (err error)
+//sys	utimes(path string, times *[2]Timeval) (err error)
+
+func setTimespec(sec, nsec int64) Timespec {
+	return Timespec{Sec: sec, Nsec: nsec}
+}
+
+func setTimeval(sec, usec int64) Timeval {
+	return Timeval{Sec: sec, Usec: usec}
+}
+
+func (r *PtraceRegs) PC() uint64 { return r.Rip }
+
+func (r *PtraceRegs) SetPC(pc uint64) { r.Rip = pc }
+
+func (iov *Iovec) SetLen(length int) {
+	iov.Len = uint64(length)
+}
+
+func (msghdr *Msghdr) SetControllen(length int) {
+	msghdr.Controllen = uint64(length)
+}
+
+func (cmsg *Cmsghdr) SetLen(length int) {
+	cmsg.Len = uint64(length)
+}
+
+func rawVforkSyscall(trap, a1 uintptr) (r1 uintptr, err Errno)
diff --git a/contrib/go/_std_1.19/src/syscall/syscall_unix.go b/contrib/go/_std_1.19/src/syscall/syscall_unix.go
new file mode 100644
index 0000000000..cf0e238e2f
--- /dev/null
+++ b/contrib/go/_std_1.19/src/syscall/syscall_unix.go
@@ -0,0 +1,518 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix
+
+package syscall
+
+import (
+	"internal/bytealg"
+	"internal/itoa"
+	"internal/oserror"
+	"internal/race"
+	"internal/unsafeheader"
+	"runtime"
+	"sync"
+	"unsafe"
+)
+
+var (
+	Stdin  = 0
+	Stdout = 1
+	Stderr = 2
+)
+
+const (
+	darwin64Bit = (runtime.GOOS == "darwin" || runtime.GOOS == "ios") && sizeofPtr == 8
+	netbsd32Bit = runtime.GOOS == "netbsd" && sizeofPtr == 4
+)
+
+// clen returns the index of the first NULL byte in n or len(n) if n contains no NULL byte.
+func clen(n []byte) int {
+	if i := bytealg.IndexByte(n, 0); i != -1 {
+		return i
+	}
+	return len(n)
+}
+
+// Mmap manager, for use by operating system-specific implementations.
+
+type mmapper struct {
+	sync.Mutex
+	active map[*byte][]byte // active mappings; key is last byte in mapping
+	mmap   func(addr, length uintptr, prot, flags, fd int, offset int64) (uintptr, error)
+	munmap func(addr uintptr, length uintptr) error
+}
+
+func (m *mmapper) Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error) {
+	if length <= 0 {
+		return nil, EINVAL
+	}
+
+	// Map the requested memory.
+	addr, errno := m.mmap(0, uintptr(length), prot, flags, fd, offset)
+	if errno != nil {
+		return nil, errno
+	}
+
+	// Use unsafe to turn addr into a []byte.
+	var b []byte
+	hdr := (*unsafeheader.Slice)(unsafe.Pointer(&b))
+	hdr.Data = unsafe.Pointer(addr)
+	hdr.Cap = length
+	hdr.Len = length
+
+	// Register mapping in m and return it.
+	p := &b[cap(b)-1]
+	m.Lock()
+	defer m.Unlock()
+	m.active[p] = b
+	return b, nil
+}
+
+func (m *mmapper) Munmap(data []byte) (err error) {
+	if len(data) == 0 || len(data) != cap(data) {
+		return EINVAL
+	}
+
+	// Find the base of the mapping.
+	p := &data[cap(data)-1]
+	m.Lock()
+	defer m.Unlock()
+	b := m.active[p]
+	if b == nil || &b[0] != &data[0] {
+		return EINVAL
+	}
+
+	// Unmap the memory and update m.
+	if errno := m.munmap(uintptr(unsafe.Pointer(&b[0])), uintptr(len(b))); errno != nil {
+		return errno
+	}
+	delete(m.active, p)
+	return nil
+}
+
+// An Errno is an unsigned number describing an error condition.
+// It implements the error interface. The zero Errno is by convention
+// a non-error, so code to convert from Errno to error should use:
+//
+//	err = nil
+//	if errno != 0 {
+//		err = errno
+//	}
+//
+// Errno values can be tested against error values from the os package
+// using errors.Is. For example:
+//
+//	_, _, err := syscall.Syscall(...)
+//	if errors.Is(err, fs.ErrNotExist) ...
+type Errno uintptr
+
+func (e Errno) Error() string {
+	if 0 <= int(e) && int(e) < len(errors) {
+		s := errors[e]
+		if s != "" {
+			return s
+		}
+	}
+	return "errno " + itoa.Itoa(int(e))
+}
+
+func (e Errno) Is(target error) bool {
+	switch target {
+	case oserror.ErrPermission:
+		return e == EACCES || e == EPERM
+	case oserror.ErrExist:
+		return e == EEXIST || e == ENOTEMPTY
+	case oserror.ErrNotExist:
+		return e == ENOENT
+	}
+	return false
+}
+
+func (e Errno) Temporary() bool {
+	return e == EINTR || e == EMFILE || e == ENFILE || e.Timeout()
+}
+
+func (e Errno) Timeout() bool {
+	return e == EAGAIN || e == EWOULDBLOCK || e == ETIMEDOUT
+}
+
+// Do the interface allocations only once for common
+// Errno values.
+var (
+	errEAGAIN error = EAGAIN
+	errEINVAL error = EINVAL
+	errENOENT error = ENOENT
+)
+
+// errnoErr returns common boxed Errno values, to prevent
+// allocations at runtime.
+func errnoErr(e Errno) error {
+	switch e {
+	case 0:
+		return nil
+	case EAGAIN:
+		return errEAGAIN
+	case EINVAL:
+		return errEINVAL
+	case ENOENT:
+		return errENOENT
+	}
+	return e
+}
+
+// A Signal is a number describing a process signal.
+// It implements the os.Signal interface.
+type Signal int
+
+func (s Signal) Signal() {}
+
+func (s Signal) String() string {
+	if 0 <= s && int(s) < len(signals) {
+		str := signals[s]
+		if str != "" {
+			return str
+		}
+	}
+	return "signal " + itoa.Itoa(int(s))
+}
+
+func Read(fd int, p []byte) (n int, err error) {
+	n, err = read(fd, p)
+	if race.Enabled {
+		if n > 0 {
+			race.WriteRange(unsafe.Pointer(&p[0]), n)
+		}
+		if err == nil {
+			race.Acquire(unsafe.Pointer(&ioSync))
+		}
+	}
+	if msanenabled && n > 0 {
+		msanWrite(unsafe.Pointer(&p[0]), n)
+	}
+	if asanenabled && n > 0 {
+		asanWrite(unsafe.Pointer(&p[0]), n)
+	}
+	return
+}
+
+func Write(fd int, p []byte) (n int, err error) {
+	if race.Enabled {
+		race.ReleaseMerge(unsafe.Pointer(&ioSync))
+	}
+	if faketime && (fd == 1 || fd == 2) {
+		n = faketimeWrite(fd, p)
+		if n < 0 {
+			n, err = 0, errnoErr(Errno(-n))
+		}
+	} else {
+		n, err = write(fd, p)
+	}
+	if race.Enabled && n > 0 {
+		race.ReadRange(unsafe.Pointer(&p[0]), n)
+	}
+	if msanenabled && n > 0 {
+		msanRead(unsafe.Pointer(&p[0]), n)
+	}
+	if asanenabled && n > 0 {
+		asanRead(unsafe.Pointer(&p[0]), n)
+	}
+	return
+}
+
+func Pread(fd int, p []byte, offset int64) (n int, err error) {
+	n, err = pread(fd, p, offset)
+	if race.Enabled {
+		if n > 0 {
+			race.WriteRange(unsafe.Pointer(&p[0]), n)
+		}
+		if err == nil {
+			race.Acquire(unsafe.Pointer(&ioSync))
+		}
+	}
+	if msanenabled && n > 0 {
+		msanWrite(unsafe.Pointer(&p[0]), n)
+	}
+	if asanenabled && n > 0 {
+		asanWrite(unsafe.Pointer(&p[0]), n)
+	}
+	return
+}
+
+func Pwrite(fd int, p []byte, offset int64) (n int, err error) {
+	if race.Enabled {
+		race.ReleaseMerge(unsafe.Pointer(&ioSync))
+	}
+	n, err = pwrite(fd, p, offset)
+	if race.Enabled && n > 0 {
+		race.ReadRange(unsafe.Pointer(&p[0]), n)
+	}
+	if msanenabled && n > 0 {
+		msanRead(unsafe.Pointer(&p[0]), n)
+	}
+	if asanenabled && n > 0 {
+		asanRead(unsafe.Pointer(&p[0]), n)
+	}
+	return
+}
+
+// For testing: clients can set this flag to force
+// creation of IPv6 sockets to return EAFNOSUPPORT.
+var SocketDisableIPv6 bool
+
+type Sockaddr interface {
+	sockaddr() (ptr unsafe.Pointer, len _Socklen, err error) // lowercase; only we can define Sockaddrs
+}
+
+type SockaddrInet4 struct {
+	Port int
+	Addr [4]byte
+	raw  RawSockaddrInet4
+}
+
+type SockaddrInet6 struct {
+	Port   int
+	ZoneId uint32
+	Addr   [16]byte
+	raw    RawSockaddrInet6
+}
+
+type SockaddrUnix struct {
+	Name string
+	raw  RawSockaddrUnix
+}
+
+func Bind(fd int, sa Sockaddr) (err error) {
+	ptr, n, err := sa.sockaddr()
+	if err != nil {
+		return err
+	}
+	return bind(fd, ptr, n)
+}
+
+func Connect(fd int, sa Sockaddr) (err error) {
+	ptr, n, err := sa.sockaddr()
+	if err != nil {
+		return err
+	}
+	return connect(fd, ptr, n)
+}
+
+func Getpeername(fd int) (sa Sockaddr, err error) {
+	var rsa RawSockaddrAny
+	var len _Socklen = SizeofSockaddrAny
+	if err = getpeername(fd, &rsa, &len); err != nil {
+		return
+	}
+	return anyToSockaddr(&rsa)
+}
+
+func GetsockoptInt(fd, level, opt int) (value int, err error) {
+	var n int32
+	vallen := _Socklen(4)
+	err = getsockopt(fd, level, opt, unsafe.Pointer(&n), &vallen)
+	return int(n), err
+}
+
+func Recvfrom(fd int, p []byte, flags int) (n int, from Sockaddr, err error) {
+	var rsa RawSockaddrAny
+	var len _Socklen = SizeofSockaddrAny
+	if n, err = recvfrom(fd, p, flags, &rsa, &len); err != nil {
+		return
+	}
+	if rsa.Addr.Family != AF_UNSPEC {
+		from, err = anyToSockaddr(&rsa)
+	}
+	return
+}
+
+func recvfromInet4(fd int, p []byte, flags int, from *SockaddrInet4) (n int, err error) {
+	var rsa RawSockaddrAny
+	var socklen _Socklen = SizeofSockaddrAny
+	if n, err = recvfrom(fd, p, flags, &rsa, &socklen); err != nil {
+		return
+	}
+	pp := (*RawSockaddrInet4)(unsafe.Pointer(&rsa))
+	port := (*[2]byte)(unsafe.Pointer(&pp.Port))
+	from.Port = int(port[0])<<8 + int(port[1])
+	from.Addr = pp.Addr
+	return
+}
+
+func recvfromInet6(fd int, p []byte, flags int, from *SockaddrInet6) (n int, err error) {
+	var rsa RawSockaddrAny
+	var socklen _Socklen = SizeofSockaddrAny
+	if n, err = recvfrom(fd, p, flags, &rsa, &socklen); err != nil {
+		return
+	}
+	pp := (*RawSockaddrInet6)(unsafe.Pointer(&rsa))
+	port := (*[2]byte)(unsafe.Pointer(&pp.Port))
+	from.Port = int(port[0])<<8 + int(port[1])
+	from.ZoneId = pp.Scope_id
+	from.Addr = pp.Addr
+	return
+}
+
+func recvmsgInet4(fd int, p, oob []byte, flags int, from *SockaddrInet4) (n, oobn int, recvflags int, err error) {
+	var rsa RawSockaddrAny
+	n, oobn, recvflags, err = recvmsgRaw(fd, p, oob, flags, &rsa)
+	if err != nil {
+		return
+	}
+	pp := (*RawSockaddrInet4)(unsafe.Pointer(&rsa))
+	port := (*[2]byte)(unsafe.Pointer(&pp.Port))
+	from.Port = int(port[0])<<8 + int(port[1])
+	from.Addr = pp.Addr
+	return
+}
+
+func recvmsgInet6(fd int, p, oob []byte, flags int, from *SockaddrInet6) (n, oobn int, recvflags int, err error) {
+	var rsa RawSockaddrAny
+	n, oobn, recvflags, err = recvmsgRaw(fd, p, oob, flags, &rsa)
+	if err != nil {
+		return
+	}
+	pp := (*RawSockaddrInet6)(unsafe.Pointer(&rsa))
+	port := (*[2]byte)(unsafe.Pointer(&pp.Port))
+	from.Port = int(port[0])<<8 + int(port[1])
+	from.ZoneId = pp.Scope_id
+	from.Addr = pp.Addr
+	return
+}
+
+func Recvmsg(fd int, p, oob []byte, flags int) (n, oobn int, recvflags int, from Sockaddr, err error) {
+	var rsa RawSockaddrAny
+	n, oobn, recvflags, err = recvmsgRaw(fd, p, oob, flags, &rsa)
+	// source address is only specified if the socket is unconnected
+	if rsa.Addr.Family != AF_UNSPEC {
+		from, err = anyToSockaddr(&rsa)
+	}
+	return
+}
+
+func Sendmsg(fd int, p, oob []byte, to Sockaddr, flags int) (err error) {
+	_, err = SendmsgN(fd, p, oob, to, flags)
+	return
+}
+
+func SendmsgN(fd int, p, oob []byte, to Sockaddr, flags int) (n int, err error) {
+	var ptr unsafe.Pointer
+	var salen _Socklen
+	if to != nil {
+		ptr, salen, err = to.sockaddr()
+		if err != nil {
+			return 0, err
+		}
+	}
+	return sendmsgN(fd, p, oob, ptr, salen, flags)
+}
+
+func sendmsgNInet4(fd int, p, oob []byte, to *SockaddrInet4, flags int) (n int, err error) {
+	ptr, salen, err := to.sockaddr()
+	if err != nil {
+		return 0, err
+	}
+	return sendmsgN(fd, p, oob, ptr, salen, flags)
+}
+
+func sendmsgNInet6(fd int, p, oob []byte, to *SockaddrInet6, flags int) (n int, err error) {
+	ptr, salen, err := to.sockaddr()
+	if err != nil {
+		return 0, err
+	}
+	return sendmsgN(fd, p, oob, ptr, salen, flags)
+}
+
+func sendtoInet4(fd int, p []byte, flags int, to *SockaddrInet4) (err error) {
+	ptr, n, err := to.sockaddr()
+	if err != nil {
+		return err
+	}
+	return sendto(fd, p, flags, ptr, n)
+}
+
+func sendtoInet6(fd int, p []byte, flags int, to *SockaddrInet6) (err error) {
+	ptr, n, err := to.sockaddr()
+	if err != nil {
+		return err
+	}
+	return sendto(fd, p, flags, ptr, n)
+}
+
+func Sendto(fd int, p []byte, flags int, to Sockaddr) (err error) {
+	ptr, n, err := to.sockaddr()
+	if err != nil {
+		return err
+	}
+	return sendto(fd, p, flags, ptr, n)
+}
+
+func SetsockoptByte(fd, level, opt int, value byte) (err error) {
+	return setsockopt(fd, level, opt, unsafe.Pointer(&value), 1)
+}
+
+func SetsockoptInt(fd, level, opt int, value int) (err error) {
+	var n = int32(value)
+	return setsockopt(fd, level, opt, unsafe.Pointer(&n), 4)
+}
+
+func SetsockoptInet4Addr(fd, level, opt int, value [4]byte) (err error) {
+	return setsockopt(fd, level, opt, unsafe.Pointer(&value[0]), 4)
+}
+
+func SetsockoptIPMreq(fd, level, opt int, mreq *IPMreq) (err error) {
+	return setsockopt(fd, level, opt, unsafe.Pointer(mreq), SizeofIPMreq)
+}
+
+func SetsockoptIPv6Mreq(fd, level, opt int, mreq *IPv6Mreq) (err error) {
+	return setsockopt(fd, level, opt, unsafe.Pointer(mreq), SizeofIPv6Mreq)
+}
+
+func SetsockoptICMPv6Filter(fd, level, opt int, filter *ICMPv6Filter) error {
+	return setsockopt(fd, level, opt, unsafe.Pointer(filter), SizeofICMPv6Filter)
+}
+
+func SetsockoptLinger(fd, level, opt int, l *Linger) (err error) {
+	return setsockopt(fd, level, opt, unsafe.Pointer(l), SizeofLinger)
+}
+
+func SetsockoptString(fd, level, opt int, s string) (err error) {
+	var p unsafe.Pointer
+	if len(s) > 0 {
+		p = unsafe.Pointer(&[]byte(s)[0])
+	}
+	return setsockopt(fd, level, opt, p, uintptr(len(s)))
+}
+
+func SetsockoptTimeval(fd, level, opt int, tv *Timeval) (err error) {
+	return setsockopt(fd, level, opt, unsafe.Pointer(tv), unsafe.Sizeof(*tv))
+}
+
+func Socket(domain, typ, proto int) (fd int, err error) {
+	if domain == AF_INET6 && SocketDisableIPv6 {
+		return -1, EAFNOSUPPORT
+	}
+	fd, err = socket(domain, typ, proto)
+	return
+}
+
+func Socketpair(domain, typ, proto int) (fd [2]int, err error) {
+	var fdx [2]int32
+	err = socketpair(domain, typ, proto, &fdx)
+	if err == nil {
+		fd[0] = int(fdx[0])
+		fd[1] = int(fdx[1])
+	}
+	return
+}
+
+func Sendfile(outfd int, infd int, offset *int64, count int) (written int, err error) {
+	if race.Enabled {
+		race.ReleaseMerge(unsafe.Pointer(&ioSync))
+	}
+	return sendfile(outfd, infd, offset, count)
+}
+
+var ioSync int64
diff --git a/contrib/go/_std_1.18/src/syscall/time_nofake.go b/contrib/go/_std_1.19/src/syscall/time_nofake.go
index 231875d8c3..231875d8c3 100644
--- a/contrib/go/_std_1.18/src/syscall/time_nofake.go
+++ b/contrib/go/_std_1.19/src/syscall/time_nofake.go
diff --git a/contrib/go/_std_1.19/src/syscall/timestruct.go b/contrib/go/_std_1.19/src/syscall/timestruct.go
new file mode 100644
index 0000000000..8a03171ee5
--- /dev/null
+++ b/contrib/go/_std_1.19/src/syscall/timestruct.go
@@ -0,0 +1,36 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm)
+
+package syscall
+
+// TimespecToNSec returns the time stored in ts as nanoseconds.
+func TimespecToNsec(ts Timespec) int64 { return ts.Nano() }
+
+// NsecToTimespec converts a number of nanoseconds into a Timespec.
+func NsecToTimespec(nsec int64) Timespec {
+	sec := nsec / 1e9
+	nsec = nsec % 1e9
+	if nsec < 0 {
+		nsec += 1e9
+		sec--
+	}
+	return setTimespec(sec, nsec)
+}
+
+// TimevalToNsec returns the time stored in tv as nanoseconds.
+func TimevalToNsec(tv Timeval) int64 { return tv.Nano() }
+
+// NsecToTimeval converts a number of nanoseconds into a Timeval.
+func NsecToTimeval(nsec int64) Timeval {
+	nsec += 999 // round up to microsecond
+	usec := nsec % 1e9 / 1e3
+	sec := nsec / 1e9
+	if usec < 0 {
+		usec += 1e6
+		sec--
+	}
+	return setTimeval(sec, usec)
+}
diff --git a/contrib/go/_std_1.18/src/syscall/zerrors_darwin_amd64.go b/contrib/go/_std_1.19/src/syscall/zerrors_darwin_amd64.go
index ecbe89c547..ecbe89c547 100644
--- a/contrib/go/_std_1.18/src/syscall/zerrors_darwin_amd64.go
+++ b/contrib/go/_std_1.19/src/syscall/zerrors_darwin_amd64.go
diff --git a/contrib/go/_std_1.18/src/syscall/zerrors_linux_amd64.go b/contrib/go/_std_1.19/src/syscall/zerrors_linux_amd64.go
index 3ff6e498e7..3ff6e498e7 100644
--- a/contrib/go/_std_1.18/src/syscall/zerrors_linux_amd64.go
+++ b/contrib/go/_std_1.19/src/syscall/zerrors_linux_amd64.go
diff --git a/contrib/go/_std_1.19/src/syscall/zsyscall_darwin_amd64.go b/contrib/go/_std_1.19/src/syscall/zsyscall_darwin_amd64.go
new file mode 100644
index 0000000000..ee78a572fc
--- /dev/null
+++ b/contrib/go/_std_1.19/src/syscall/zsyscall_darwin_amd64.go
@@ -0,0 +1,2004 @@
+// mksyscall.pl -darwin -tags darwin,amd64 syscall_bsd.go syscall_darwin.go syscall_darwin_amd64.go
+// Code generated by the command above; DO NOT EDIT.
+
+//go:build darwin && amd64
+
+package syscall
+
+import "unsafe"
+import "internal/abi"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func getgroups(ngid int, gid *_Gid_t) (n int, err error) {
+	r0, _, e1 := rawSyscall(abi.FuncPCABI0(libc_getgroups_trampoline), uintptr(ngid), uintptr(unsafe.Pointer(gid)), 0)
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_getgroups_trampoline()
+
+//go:cgo_import_dynamic libc_getgroups getgroups "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func setgroups(ngid int, gid *_Gid_t) (err error) {
+	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_setgroups_trampoline), uintptr(ngid), uintptr(unsafe.Pointer(gid)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_setgroups_trampoline()
+
+//go:cgo_import_dynamic libc_setgroups setgroups "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func wait4(pid int, wstatus *_C_int, options int, rusage *Rusage) (wpid int, err error) {
+	r0, _, e1 := syscall6(abi.FuncPCABI0(libc_wait4_trampoline), uintptr(pid), uintptr(unsafe.Pointer(wstatus)), uintptr(options), uintptr(unsafe.Pointer(rusage)), 0, 0)
+	wpid = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_wait4_trampoline()
+
+//go:cgo_import_dynamic libc_wait4 wait4 "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func accept(s int, rsa *RawSockaddrAny, addrlen *_Socklen) (fd int, err error) {
+	r0, _, e1 := syscall(abi.FuncPCABI0(libc_accept_trampoline), uintptr(s), uintptr(unsafe.Pointer(rsa)), uintptr(unsafe.Pointer(addrlen)))
+	fd = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_accept_trampoline()
+
+//go:cgo_import_dynamic libc_accept accept "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func bind(s int, addr unsafe.Pointer, addrlen _Socklen) (err error) {
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_bind_trampoline), uintptr(s), uintptr(addr), uintptr(addrlen))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_bind_trampoline()
+
+//go:cgo_import_dynamic libc_bind bind "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func connect(s int, addr unsafe.Pointer, addrlen _Socklen) (err error) {
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_connect_trampoline), uintptr(s), uintptr(addr), uintptr(addrlen))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_connect_trampoline()
+
+//go:cgo_import_dynamic libc_connect connect "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func socket(domain int, typ int, proto int) (fd int, err error) {
+	r0, _, e1 := rawSyscall(abi.FuncPCABI0(libc_socket_trampoline), uintptr(domain), uintptr(typ), uintptr(proto))
+	fd = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_socket_trampoline()
+
+//go:cgo_import_dynamic libc_socket socket "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func getsockopt(s int, level int, name int, val unsafe.Pointer, vallen *_Socklen) (err error) {
+	_, _, e1 := syscall6(abi.FuncPCABI0(libc_getsockopt_trampoline), uintptr(s), uintptr(level), uintptr(name), uintptr(val), uintptr(unsafe.Pointer(vallen)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_getsockopt_trampoline()
+
+//go:cgo_import_dynamic libc_getsockopt getsockopt "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func setsockopt(s int, level int, name int, val unsafe.Pointer, vallen uintptr) (err error) {
+	_, _, e1 := syscall6(abi.FuncPCABI0(libc_setsockopt_trampoline), uintptr(s), uintptr(level), uintptr(name), uintptr(val), uintptr(vallen), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_setsockopt_trampoline()
+
+//go:cgo_import_dynamic libc_setsockopt setsockopt "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func getpeername(fd int, rsa *RawSockaddrAny, addrlen *_Socklen) (err error) {
+	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_getpeername_trampoline), uintptr(fd), uintptr(unsafe.Pointer(rsa)), uintptr(unsafe.Pointer(addrlen)))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_getpeername_trampoline()
+
+//go:cgo_import_dynamic libc_getpeername getpeername "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func getsockname(fd int, rsa *RawSockaddrAny, addrlen *_Socklen) (err error) {
+	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_getsockname_trampoline), uintptr(fd), uintptr(unsafe.Pointer(rsa)), uintptr(unsafe.Pointer(addrlen)))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_getsockname_trampoline()
+
+//go:cgo_import_dynamic libc_getsockname getsockname "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Shutdown(s int, how int) (err error) {
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_shutdown_trampoline), uintptr(s), uintptr(how), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_shutdown_trampoline()
+
+//go:cgo_import_dynamic libc_shutdown shutdown "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func socketpair(domain int, typ int, proto int, fd *[2]int32) (err error) {
+	_, _, e1 := rawSyscall6(abi.FuncPCABI0(libc_socketpair_trampoline), uintptr(domain), uintptr(typ), uintptr(proto), uintptr(unsafe.Pointer(fd)), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_socketpair_trampoline()
+
+//go:cgo_import_dynamic libc_socketpair socketpair "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func recvfrom(fd int, p []byte, flags int, from *RawSockaddrAny, fromlen *_Socklen) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(p) > 0 {
+		_p0 = unsafe.Pointer(&p[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall6(abi.FuncPCABI0(libc_recvfrom_trampoline), uintptr(fd), uintptr(_p0), uintptr(len(p)), uintptr(flags), uintptr(unsafe.Pointer(from)), uintptr(unsafe.Pointer(fromlen)))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_recvfrom_trampoline()
+
+//go:cgo_import_dynamic libc_recvfrom recvfrom "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func sendto(s int, buf []byte, flags int, to unsafe.Pointer, addrlen _Socklen) (err error) {
+	var _p0 unsafe.Pointer
+	if len(buf) > 0 {
+		_p0 = unsafe.Pointer(&buf[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	_, _, e1 := syscall6(abi.FuncPCABI0(libc_sendto_trampoline), uintptr(s), uintptr(_p0), uintptr(len(buf)), uintptr(flags), uintptr(to), uintptr(addrlen))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_sendto_trampoline()
+
+//go:cgo_import_dynamic libc_sendto sendto "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func recvmsg(s int, msg *Msghdr, flags int) (n int, err error) {
+	r0, _, e1 := syscall(abi.FuncPCABI0(libc_recvmsg_trampoline), uintptr(s), uintptr(unsafe.Pointer(msg)), uintptr(flags))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_recvmsg_trampoline()
+
+//go:cgo_import_dynamic libc_recvmsg recvmsg "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func sendmsg(s int, msg *Msghdr, flags int) (n int, err error) {
+	r0, _, e1 := syscall(abi.FuncPCABI0(libc_sendmsg_trampoline), uintptr(s), uintptr(unsafe.Pointer(msg)), uintptr(flags))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_sendmsg_trampoline()
+
+//go:cgo_import_dynamic libc_sendmsg sendmsg "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func kevent(kq int, change unsafe.Pointer, nchange int, event unsafe.Pointer, nevent int, timeout *Timespec) (n int, err error) {
+	r0, _, e1 := syscall6(abi.FuncPCABI0(libc_kevent_trampoline), uintptr(kq), uintptr(change), uintptr(nchange), uintptr(event), uintptr(nevent), uintptr(unsafe.Pointer(timeout)))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_kevent_trampoline()
+
+//go:cgo_import_dynamic libc_kevent kevent "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func utimes(path string, timeval *[2]Timeval) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_utimes_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(timeval)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_utimes_trampoline()
+
+//go:cgo_import_dynamic libc_utimes utimes "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func futimes(fd int, timeval *[2]Timeval) (err error) {
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_futimes_trampoline), uintptr(fd), uintptr(unsafe.Pointer(timeval)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_futimes_trampoline()
+
+//go:cgo_import_dynamic libc_futimes futimes "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func fcntl(fd int, cmd int, arg int) (val int, err error) {
+	r0, _, e1 := syscall(abi.FuncPCABI0(libc_fcntl_trampoline), uintptr(fd), uintptr(cmd), uintptr(arg))
+	val = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_fcntl_trampoline()
+
+//go:cgo_import_dynamic libc_fcntl fcntl "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func pipe(p *[2]int32) (err error) {
+	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_pipe_trampoline), uintptr(unsafe.Pointer(p)), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_pipe_trampoline()
+
+//go:cgo_import_dynamic libc_pipe pipe "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func utimensat(dirfd int, path string, times *[2]Timespec, flags int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall6(abi.FuncPCABI0(libc_utimensat_trampoline), uintptr(dirfd), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(times)), uintptr(flags), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_utimensat_trampoline()
+
+//go:cgo_import_dynamic libc_utimensat utimensat "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func kill(pid int, signum int, posix int) (err error) {
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_kill_trampoline), uintptr(pid), uintptr(signum), uintptr(posix))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_kill_trampoline()
+
+//go:cgo_import_dynamic libc_kill kill "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Access(path string, mode uint32) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_access_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(mode), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_access_trampoline()
+
+//go:cgo_import_dynamic libc_access access "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Adjtime(delta *Timeval, olddelta *Timeval) (err error) {
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_adjtime_trampoline), uintptr(unsafe.Pointer(delta)), uintptr(unsafe.Pointer(olddelta)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_adjtime_trampoline()
+
+//go:cgo_import_dynamic libc_adjtime adjtime "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Chdir(path string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_chdir_trampoline), uintptr(unsafe.Pointer(_p0)), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_chdir_trampoline()
+
+//go:cgo_import_dynamic libc_chdir chdir "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Chflags(path string, flags int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_chflags_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(flags), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_chflags_trampoline()
+
+//go:cgo_import_dynamic libc_chflags chflags "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Chmod(path string, mode uint32) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_chmod_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(mode), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_chmod_trampoline()
+
+//go:cgo_import_dynamic libc_chmod chmod "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Chown(path string, uid int, gid int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_chown_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(uid), uintptr(gid))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_chown_trampoline()
+
+//go:cgo_import_dynamic libc_chown chown "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Chroot(path string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_chroot_trampoline), uintptr(unsafe.Pointer(_p0)), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_chroot_trampoline()
+
+//go:cgo_import_dynamic libc_chroot chroot "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Close(fd int) (err error) {
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_close_trampoline), uintptr(fd), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_close_trampoline()
+
+//go:cgo_import_dynamic libc_close close "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func closedir(dir uintptr) (err error) {
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_closedir_trampoline), uintptr(dir), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_closedir_trampoline()
+
+//go:cgo_import_dynamic libc_closedir closedir "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Dup(fd int) (nfd int, err error) {
+	r0, _, e1 := syscall(abi.FuncPCABI0(libc_dup_trampoline), uintptr(fd), 0, 0)
+	nfd = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_dup_trampoline()
+
+//go:cgo_import_dynamic libc_dup dup "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Dup2(from int, to int) (err error) {
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_dup2_trampoline), uintptr(from), uintptr(to), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_dup2_trampoline()
+
+//go:cgo_import_dynamic libc_dup2 dup2 "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Exchangedata(path1 string, path2 string, options int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path1)
+	if err != nil {
+		return
+	}
+	var _p1 *byte
+	_p1, err = BytePtrFromString(path2)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_exchangedata_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(_p1)), uintptr(options))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_exchangedata_trampoline()
+
+//go:cgo_import_dynamic libc_exchangedata exchangedata "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fchdir(fd int) (err error) {
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_fchdir_trampoline), uintptr(fd), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_fchdir_trampoline()
+
+//go:cgo_import_dynamic libc_fchdir fchdir "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fchflags(fd int, flags int) (err error) {
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_fchflags_trampoline), uintptr(fd), uintptr(flags), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_fchflags_trampoline()
+
+//go:cgo_import_dynamic libc_fchflags fchflags "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fchmod(fd int, mode uint32) (err error) {
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_fchmod_trampoline), uintptr(fd), uintptr(mode), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_fchmod_trampoline()
+
+//go:cgo_import_dynamic libc_fchmod fchmod "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fchown(fd int, uid int, gid int) (err error) {
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_fchown_trampoline), uintptr(fd), uintptr(uid), uintptr(gid))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_fchown_trampoline()
+
+//go:cgo_import_dynamic libc_fchown fchown "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Flock(fd int, how int) (err error) {
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_flock_trampoline), uintptr(fd), uintptr(how), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_flock_trampoline()
+
+//go:cgo_import_dynamic libc_flock flock "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fpathconf(fd int, name int) (val int, err error) {
+	r0, _, e1 := syscall(abi.FuncPCABI0(libc_fpathconf_trampoline), uintptr(fd), uintptr(name), 0)
+	val = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_fpathconf_trampoline()
+
+//go:cgo_import_dynamic libc_fpathconf fpathconf "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fsync(fd int) (err error) {
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_fsync_trampoline), uintptr(fd), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_fsync_trampoline()
+
+//go:cgo_import_dynamic libc_fsync fsync "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Ftruncate(fd int, length int64) (err error) {
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_ftruncate_trampoline), uintptr(fd), uintptr(length), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_ftruncate_trampoline()
+
+//go:cgo_import_dynamic libc_ftruncate ftruncate "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Getdtablesize() (size int) {
+	r0, _, _ := syscall(abi.FuncPCABI0(libc_getdtablesize_trampoline), 0, 0, 0)
+	size = int(r0)
+	return
+}
+
+func libc_getdtablesize_trampoline()
+
+//go:cgo_import_dynamic libc_getdtablesize getdtablesize "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Getegid() (egid int) {
+	r0, _, _ := rawSyscall(abi.FuncPCABI0(libc_getegid_trampoline), 0, 0, 0)
+	egid = int(r0)
+	return
+}
+
+func libc_getegid_trampoline()
+
+//go:cgo_import_dynamic libc_getegid getegid "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Geteuid() (uid int) {
+	r0, _, _ := rawSyscall(abi.FuncPCABI0(libc_geteuid_trampoline), 0, 0, 0)
+	uid = int(r0)
+	return
+}
+
+func libc_geteuid_trampoline()
+
+//go:cgo_import_dynamic libc_geteuid geteuid "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Getgid() (gid int) {
+	r0, _, _ := rawSyscall(abi.FuncPCABI0(libc_getgid_trampoline), 0, 0, 0)
+	gid = int(r0)
+	return
+}
+
+func libc_getgid_trampoline()
+
+//go:cgo_import_dynamic libc_getgid getgid "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Getpgid(pid int) (pgid int, err error) {
+	r0, _, e1 := rawSyscall(abi.FuncPCABI0(libc_getpgid_trampoline), uintptr(pid), 0, 0)
+	pgid = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_getpgid_trampoline()
+
+//go:cgo_import_dynamic libc_getpgid getpgid "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Getpgrp() (pgrp int) {
+	r0, _, _ := rawSyscall(abi.FuncPCABI0(libc_getpgrp_trampoline), 0, 0, 0)
+	pgrp = int(r0)
+	return
+}
+
+func libc_getpgrp_trampoline()
+
+//go:cgo_import_dynamic libc_getpgrp getpgrp "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Getpid() (pid int) {
+	r0, _, _ := rawSyscall(abi.FuncPCABI0(libc_getpid_trampoline), 0, 0, 0)
+	pid = int(r0)
+	return
+}
+
+func libc_getpid_trampoline()
+
+//go:cgo_import_dynamic libc_getpid getpid "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Getppid() (ppid int) {
+	r0, _, _ := rawSyscall(abi.FuncPCABI0(libc_getppid_trampoline), 0, 0, 0)
+	ppid = int(r0)
+	return
+}
+
+func libc_getppid_trampoline()
+
+//go:cgo_import_dynamic libc_getppid getppid "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Getpriority(which int, who int) (prio int, err error) {
+	r0, _, e1 := syscall(abi.FuncPCABI0(libc_getpriority_trampoline), uintptr(which), uintptr(who), 0)
+	prio = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_getpriority_trampoline()
+
+//go:cgo_import_dynamic libc_getpriority getpriority "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Getrlimit(which int, lim *Rlimit) (err error) {
+	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_getrlimit_trampoline), uintptr(which), uintptr(unsafe.Pointer(lim)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_getrlimit_trampoline()
+
+//go:cgo_import_dynamic libc_getrlimit getrlimit "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Getrusage(who int, rusage *Rusage) (err error) {
+	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_getrusage_trampoline), uintptr(who), uintptr(unsafe.Pointer(rusage)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_getrusage_trampoline()
+
+//go:cgo_import_dynamic libc_getrusage getrusage "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Getsid(pid int) (sid int, err error) {
+	r0, _, e1 := rawSyscall(abi.FuncPCABI0(libc_getsid_trampoline), uintptr(pid), 0, 0)
+	sid = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_getsid_trampoline()
+
+//go:cgo_import_dynamic libc_getsid getsid "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Getuid() (uid int) {
+	r0, _, _ := rawSyscall(abi.FuncPCABI0(libc_getuid_trampoline), 0, 0, 0)
+	uid = int(r0)
+	return
+}
+
+func libc_getuid_trampoline()
+
+//go:cgo_import_dynamic libc_getuid getuid "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Issetugid() (tainted bool) {
+	r0, _, _ := rawSyscall(abi.FuncPCABI0(libc_issetugid_trampoline), 0, 0, 0)
+	tainted = bool(r0 != 0)
+	return
+}
+
+func libc_issetugid_trampoline()
+
+//go:cgo_import_dynamic libc_issetugid issetugid "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Kqueue() (fd int, err error) {
+	r0, _, e1 := syscall(abi.FuncPCABI0(libc_kqueue_trampoline), 0, 0, 0)
+	fd = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_kqueue_trampoline()
+
+//go:cgo_import_dynamic libc_kqueue kqueue "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Lchown(path string, uid int, gid int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_lchown_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(uid), uintptr(gid))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_lchown_trampoline()
+
+//go:cgo_import_dynamic libc_lchown lchown "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Link(path string, link string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	var _p1 *byte
+	_p1, err = BytePtrFromString(link)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_link_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(_p1)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_link_trampoline()
+
+//go:cgo_import_dynamic libc_link link "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Listen(s int, backlog int) (err error) {
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_listen_trampoline), uintptr(s), uintptr(backlog), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_listen_trampoline()
+
+//go:cgo_import_dynamic libc_listen listen "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Mkdir(path string, mode uint32) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_mkdir_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(mode), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_mkdir_trampoline()
+
+//go:cgo_import_dynamic libc_mkdir mkdir "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Mkfifo(path string, mode uint32) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_mkfifo_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(mode), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_mkfifo_trampoline()
+
+//go:cgo_import_dynamic libc_mkfifo mkfifo "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Mknod(path string, mode uint32, dev int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_mknod_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(mode), uintptr(dev))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_mknod_trampoline()
+
+//go:cgo_import_dynamic libc_mknod mknod "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Mlock(b []byte) (err error) {
+	var _p0 unsafe.Pointer
+	if len(b) > 0 {
+		_p0 = unsafe.Pointer(&b[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_mlock_trampoline), uintptr(_p0), uintptr(len(b)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_mlock_trampoline()
+
+//go:cgo_import_dynamic libc_mlock mlock "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Mlockall(flags int) (err error) {
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_mlockall_trampoline), uintptr(flags), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_mlockall_trampoline()
+
+//go:cgo_import_dynamic libc_mlockall mlockall "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Mprotect(b []byte, prot int) (err error) {
+	var _p0 unsafe.Pointer
+	if len(b) > 0 {
+		_p0 = unsafe.Pointer(&b[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_mprotect_trampoline), uintptr(_p0), uintptr(len(b)), uintptr(prot))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_mprotect_trampoline()
+
+//go:cgo_import_dynamic libc_mprotect mprotect "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Munlock(b []byte) (err error) {
+	var _p0 unsafe.Pointer
+	if len(b) > 0 {
+		_p0 = unsafe.Pointer(&b[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_munlock_trampoline), uintptr(_p0), uintptr(len(b)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_munlock_trampoline()
+
+//go:cgo_import_dynamic libc_munlock munlock "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Munlockall() (err error) {
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_munlockall_trampoline), 0, 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_munlockall_trampoline()
+
+//go:cgo_import_dynamic libc_munlockall munlockall "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Open(path string, mode int, perm uint32) (fd int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := syscall(abi.FuncPCABI0(libc_open_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(mode), uintptr(perm))
+	fd = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_open_trampoline()
+
+//go:cgo_import_dynamic libc_open open "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Pathconf(path string, name int) (val int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := syscall(abi.FuncPCABI0(libc_pathconf_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(name), 0)
+	val = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_pathconf_trampoline()
+
+//go:cgo_import_dynamic libc_pathconf pathconf "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func pread(fd int, p []byte, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(p) > 0 {
+		_p0 = unsafe.Pointer(&p[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall6(abi.FuncPCABI0(libc_pread_trampoline), uintptr(fd), uintptr(_p0), uintptr(len(p)), uintptr(offset), 0, 0)
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_pread_trampoline()
+
+//go:cgo_import_dynamic libc_pread pread "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func pwrite(fd int, p []byte, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(p) > 0 {
+		_p0 = unsafe.Pointer(&p[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall6(abi.FuncPCABI0(libc_pwrite_trampoline), uintptr(fd), uintptr(_p0), uintptr(len(p)), uintptr(offset), 0, 0)
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_pwrite_trampoline()
+
+//go:cgo_import_dynamic libc_pwrite pwrite "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func read(fd int, p []byte) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(p) > 0 {
+		_p0 = unsafe.Pointer(&p[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall(abi.FuncPCABI0(libc_read_trampoline), uintptr(fd), uintptr(_p0), uintptr(len(p)))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_read_trampoline()
+
+//go:cgo_import_dynamic libc_read read "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func readdir_r(dir uintptr, entry *Dirent, result **Dirent) (res Errno) {
+	r0, _, _ := syscall(abi.FuncPCABI0(libc_readdir_r_trampoline), uintptr(dir), uintptr(unsafe.Pointer(entry)), uintptr(unsafe.Pointer(result)))
+	res = Errno(r0)
+	return
+}
+
+func libc_readdir_r_trampoline()
+
+//go:cgo_import_dynamic libc_readdir_r readdir_r "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Readlink(path string, buf []byte) (n int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	var _p1 unsafe.Pointer
+	if len(buf) > 0 {
+		_p1 = unsafe.Pointer(&buf[0])
+	} else {
+		_p1 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall(abi.FuncPCABI0(libc_readlink_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(_p1), uintptr(len(buf)))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_readlink_trampoline()
+
+//go:cgo_import_dynamic libc_readlink readlink "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Rename(from string, to string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(from)
+	if err != nil {
+		return
+	}
+	var _p1 *byte
+	_p1, err = BytePtrFromString(to)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_rename_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(_p1)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_rename_trampoline()
+
+//go:cgo_import_dynamic libc_rename rename "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Revoke(path string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_revoke_trampoline), uintptr(unsafe.Pointer(_p0)), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_revoke_trampoline()
+
+//go:cgo_import_dynamic libc_revoke revoke "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Rmdir(path string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_rmdir_trampoline), uintptr(unsafe.Pointer(_p0)), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_rmdir_trampoline()
+
+//go:cgo_import_dynamic libc_rmdir rmdir "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Seek(fd int, offset int64, whence int) (newoffset int64, err error) {
+	r0, _, e1 := syscallX(abi.FuncPCABI0(libc_lseek_trampoline), uintptr(fd), uintptr(offset), uintptr(whence))
+	newoffset = int64(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_lseek_trampoline()
+
+//go:cgo_import_dynamic libc_lseek lseek "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Select(n int, r *FdSet, w *FdSet, e *FdSet, timeout *Timeval) (err error) {
+	_, _, e1 := syscall6(abi.FuncPCABI0(libc_select_trampoline), uintptr(n), uintptr(unsafe.Pointer(r)), uintptr(unsafe.Pointer(w)), uintptr(unsafe.Pointer(e)), uintptr(unsafe.Pointer(timeout)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_select_trampoline()
+
+//go:cgo_import_dynamic libc_select select "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Setegid(egid int) (err error) {
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_setegid_trampoline), uintptr(egid), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_setegid_trampoline()
+
+//go:cgo_import_dynamic libc_setegid setegid "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Seteuid(euid int) (err error) {
+	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_seteuid_trampoline), uintptr(euid), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_seteuid_trampoline()
+
+//go:cgo_import_dynamic libc_seteuid seteuid "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Setgid(gid int) (err error) {
+	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_setgid_trampoline), uintptr(gid), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_setgid_trampoline()
+
+//go:cgo_import_dynamic libc_setgid setgid "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Setlogin(name string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(name)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_setlogin_trampoline), uintptr(unsafe.Pointer(_p0)), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_setlogin_trampoline()
+
+//go:cgo_import_dynamic libc_setlogin setlogin "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Setpgid(pid int, pgid int) (err error) {
+	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_setpgid_trampoline), uintptr(pid), uintptr(pgid), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_setpgid_trampoline()
+
+//go:cgo_import_dynamic libc_setpgid setpgid "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Setpriority(which int, who int, prio int) (err error) {
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_setpriority_trampoline), uintptr(which), uintptr(who), uintptr(prio))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_setpriority_trampoline()
+
+//go:cgo_import_dynamic libc_setpriority setpriority "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Setprivexec(flag int) (err error) {
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_setprivexec_trampoline), uintptr(flag), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_setprivexec_trampoline()
+
+//go:cgo_import_dynamic libc_setprivexec setprivexec "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Setregid(rgid int, egid int) (err error) {
+	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_setregid_trampoline), uintptr(rgid), uintptr(egid), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_setregid_trampoline()
+
+//go:cgo_import_dynamic libc_setregid setregid "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Setreuid(ruid int, euid int) (err error) {
+	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_setreuid_trampoline), uintptr(ruid), uintptr(euid), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_setreuid_trampoline()
+
+//go:cgo_import_dynamic libc_setreuid setreuid "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Setrlimit(which int, lim *Rlimit) (err error) {
+	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_setrlimit_trampoline), uintptr(which), uintptr(unsafe.Pointer(lim)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_setrlimit_trampoline()
+
+//go:cgo_import_dynamic libc_setrlimit setrlimit "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Setsid() (pid int, err error) {
+	r0, _, e1 := rawSyscall(abi.FuncPCABI0(libc_setsid_trampoline), 0, 0, 0)
+	pid = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_setsid_trampoline()
+
+//go:cgo_import_dynamic libc_setsid setsid "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Settimeofday(tp *Timeval) (err error) {
+	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_settimeofday_trampoline), uintptr(unsafe.Pointer(tp)), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_settimeofday_trampoline()
+
+//go:cgo_import_dynamic libc_settimeofday settimeofday "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Setuid(uid int) (err error) {
+	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_setuid_trampoline), uintptr(uid), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_setuid_trampoline()
+
+//go:cgo_import_dynamic libc_setuid setuid "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Symlink(path string, link string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	var _p1 *byte
+	_p1, err = BytePtrFromString(link)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_symlink_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(_p1)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_symlink_trampoline()
+
+//go:cgo_import_dynamic libc_symlink symlink "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Sync() (err error) {
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_sync_trampoline), 0, 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_sync_trampoline()
+
+//go:cgo_import_dynamic libc_sync sync "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Truncate(path string, length int64) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_truncate_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(length), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_truncate_trampoline()
+
+//go:cgo_import_dynamic libc_truncate truncate "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Umask(newmask int) (oldmask int) {
+	r0, _, _ := syscall(abi.FuncPCABI0(libc_umask_trampoline), uintptr(newmask), 0, 0)
+	oldmask = int(r0)
+	return
+}
+
+func libc_umask_trampoline()
+
+//go:cgo_import_dynamic libc_umask umask "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Undelete(path string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_undelete_trampoline), uintptr(unsafe.Pointer(_p0)), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_undelete_trampoline()
+
+//go:cgo_import_dynamic libc_undelete undelete "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Unlink(path string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_unlink_trampoline), uintptr(unsafe.Pointer(_p0)), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_unlink_trampoline()
+
+//go:cgo_import_dynamic libc_unlink unlink "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Unmount(path string, flags int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_unmount_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(flags), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_unmount_trampoline()
+
+//go:cgo_import_dynamic libc_unmount unmount "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func write(fd int, p []byte) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(p) > 0 {
+		_p0 = unsafe.Pointer(&p[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall(abi.FuncPCABI0(libc_write_trampoline), uintptr(fd), uintptr(_p0), uintptr(len(p)))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_write_trampoline()
+
+//go:cgo_import_dynamic libc_write write "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func writev(fd int, iovecs []Iovec) (cnt uintptr, err error) {
+	var _p0 unsafe.Pointer
+	if len(iovecs) > 0 {
+		_p0 = unsafe.Pointer(&iovecs[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscallX(abi.FuncPCABI0(libc_writev_trampoline), uintptr(fd), uintptr(_p0), uintptr(len(iovecs)))
+	cnt = uintptr(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_writev_trampoline()
+
+//go:cgo_import_dynamic libc_writev writev "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func mmap(addr uintptr, length uintptr, prot int, flag int, fd int, pos int64) (ret uintptr, err error) {
+	r0, _, e1 := syscall6X(abi.FuncPCABI0(libc_mmap_trampoline), uintptr(addr), uintptr(length), uintptr(prot), uintptr(flag), uintptr(fd), uintptr(pos))
+	ret = uintptr(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_mmap_trampoline()
+
+//go:cgo_import_dynamic libc_mmap mmap "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func munmap(addr uintptr, length uintptr) (err error) {
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_munmap_trampoline), uintptr(addr), uintptr(length), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_munmap_trampoline()
+
+//go:cgo_import_dynamic libc_munmap munmap "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func fork() (pid int, err error) {
+	r0, _, e1 := rawSyscall(abi.FuncPCABI0(libc_fork_trampoline), 0, 0, 0)
+	pid = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_fork_trampoline()
+
+//go:cgo_import_dynamic libc_fork fork "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func ioctl(fd int, req int, arg int) (err error) {
+	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_ioctl_trampoline), uintptr(fd), uintptr(req), uintptr(arg))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_ioctl_trampoline()
+
+//go:cgo_import_dynamic libc_ioctl ioctl "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func ioctlPtr(fd int, req uint, arg unsafe.Pointer) (err error) {
+	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_ioctl_trampoline), uintptr(fd), uintptr(req), uintptr(arg))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func execve(path *byte, argv **byte, envp **byte) (err error) {
+	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_execve_trampoline), uintptr(unsafe.Pointer(path)), uintptr(unsafe.Pointer(argv)), uintptr(unsafe.Pointer(envp)))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_execve_trampoline()
+
+//go:cgo_import_dynamic libc_execve execve "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func exit(res int) (err error) {
+	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_exit_trampoline), uintptr(res), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_exit_trampoline()
+
+//go:cgo_import_dynamic libc_exit exit "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func sysctl(mib []_C_int, old *byte, oldlen *uintptr, new *byte, newlen uintptr) (err error) {
+	var _p0 unsafe.Pointer
+	if len(mib) > 0 {
+		_p0 = unsafe.Pointer(&mib[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	_, _, e1 := syscall6(abi.FuncPCABI0(libc_sysctl_trampoline), uintptr(_p0), uintptr(len(mib)), uintptr(unsafe.Pointer(old)), uintptr(unsafe.Pointer(oldlen)), uintptr(unsafe.Pointer(new)), uintptr(newlen))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_sysctl_trampoline()
+
+//go:cgo_import_dynamic libc_sysctl sysctl "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func fcntlPtr(fd int, cmd int, arg unsafe.Pointer) (val int, err error) {
+	r0, _, e1 := syscall(abi.FuncPCABI0(libc_fcntl_trampoline), uintptr(fd), uintptr(cmd), uintptr(arg))
+	val = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func unlinkat(fd int, path string, flags int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_unlinkat_trampoline), uintptr(fd), uintptr(unsafe.Pointer(_p0)), uintptr(flags))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_unlinkat_trampoline()
+
+//go:cgo_import_dynamic libc_unlinkat unlinkat "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func openat(fd int, path string, flags int, perm uint32) (fdret int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := syscall6(abi.FuncPCABI0(libc_openat_trampoline), uintptr(fd), uintptr(unsafe.Pointer(_p0)), uintptr(flags), uintptr(perm), 0, 0)
+	fdret = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_openat_trampoline()
+
+//go:cgo_import_dynamic libc_openat openat "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func getcwd(buf []byte) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(buf) > 0 {
+		_p0 = unsafe.Pointer(&buf[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := syscall(abi.FuncPCABI0(libc_getcwd_trampoline), uintptr(_p0), uintptr(len(buf)), 0)
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_getcwd_trampoline()
+
+//go:cgo_import_dynamic libc_getcwd getcwd "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fstat(fd int, stat *Stat_t) (err error) {
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_fstat64_trampoline), uintptr(fd), uintptr(unsafe.Pointer(stat)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_fstat64_trampoline()
+
+//go:cgo_import_dynamic libc_fstat64 fstat64 "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fstatfs(fd int, stat *Statfs_t) (err error) {
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_fstatfs64_trampoline), uintptr(fd), uintptr(unsafe.Pointer(stat)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_fstatfs64_trampoline()
+
+//go:cgo_import_dynamic libc_fstatfs64 fstatfs64 "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Gettimeofday(tp *Timeval) (err error) {
+	_, _, e1 := rawSyscall(abi.FuncPCABI0(libc_gettimeofday_trampoline), uintptr(unsafe.Pointer(tp)), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_gettimeofday_trampoline()
+
+//go:cgo_import_dynamic libc_gettimeofday gettimeofday "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Lstat(path string, stat *Stat_t) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_lstat64_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(stat)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_lstat64_trampoline()
+
+//go:cgo_import_dynamic libc_lstat64 lstat64 "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Stat(path string, stat *Stat_t) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_stat64_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(stat)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_stat64_trampoline()
+
+//go:cgo_import_dynamic libc_stat64 stat64 "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Statfs(path string, stat *Statfs_t) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall(abi.FuncPCABI0(libc_statfs64_trampoline), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(stat)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_statfs64_trampoline()
+
+//go:cgo_import_dynamic libc_statfs64 statfs64 "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func fstatat(fd int, path string, stat *Stat_t, flags int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := syscall6(abi.FuncPCABI0(libc_fstatat64_trampoline), uintptr(fd), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(stat)), uintptr(flags), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_fstatat64_trampoline()
+
+//go:cgo_import_dynamic libc_fstatat64 fstatat64 "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+//go:nosplit
+func ptrace1(request int, pid int, addr uintptr, data uintptr) (err error) {
+	_, _, e1 := syscall6(abi.FuncPCABI0(libc_ptrace_trampoline), uintptr(request), uintptr(pid), uintptr(addr), uintptr(data), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_ptrace_trampoline()
+
+//go:cgo_import_dynamic libc_ptrace ptrace "/usr/lib/libSystem.B.dylib"
diff --git a/contrib/go/_std_1.18/src/syscall/zsyscall_darwin_amd64.s b/contrib/go/_std_1.19/src/syscall/zsyscall_darwin_amd64.s
index 563083d441..563083d441 100644
--- a/contrib/go/_std_1.18/src/syscall/zsyscall_darwin_amd64.s
+++ b/contrib/go/_std_1.19/src/syscall/zsyscall_darwin_amd64.s
diff --git a/contrib/go/_std_1.19/src/syscall/zsyscall_linux_amd64.go b/contrib/go/_std_1.19/src/syscall/zsyscall_linux_amd64.go
new file mode 100644
index 0000000000..07f328e1e2
--- /dev/null
+++ b/contrib/go/_std_1.19/src/syscall/zsyscall_linux_amd64.go
@@ -0,0 +1,1644 @@
+// mksyscall.pl -tags linux,amd64 syscall_linux.go syscall_linux_amd64.go
+// Code generated by the command above; DO NOT EDIT.
+
+//go:build linux && amd64
+
+package syscall
+
+import "unsafe"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func faccessat(dirfd int, path string, mode uint32) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall(SYS_FACCESSAT, uintptr(dirfd), uintptr(unsafe.Pointer(_p0)), uintptr(mode))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func fchmodat(dirfd int, path string, mode uint32) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall(SYS_FCHMODAT, uintptr(dirfd), uintptr(unsafe.Pointer(_p0)), uintptr(mode))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func linkat(olddirfd int, oldpath string, newdirfd int, newpath string, flags int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(oldpath)
+	if err != nil {
+		return
+	}
+	var _p1 *byte
+	_p1, err = BytePtrFromString(newpath)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall6(SYS_LINKAT, uintptr(olddirfd), uintptr(unsafe.Pointer(_p0)), uintptr(newdirfd), uintptr(unsafe.Pointer(_p1)), uintptr(flags), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func openat(dirfd int, path string, flags int, mode uint32) (fd int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall6(SYS_OPENAT, uintptr(dirfd), uintptr(unsafe.Pointer(_p0)), uintptr(flags), uintptr(mode), 0, 0)
+	fd = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func pipe2(p *[2]_C_int, flags int) (err error) {
+	_, _, e1 := RawSyscall(SYS_PIPE2, uintptr(unsafe.Pointer(p)), uintptr(flags), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func readlinkat(dirfd int, path string, buf []byte) (n int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	var _p1 unsafe.Pointer
+	if len(buf) > 0 {
+		_p1 = unsafe.Pointer(&buf[0])
+	} else {
+		_p1 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall6(SYS_READLINKAT, uintptr(dirfd), uintptr(unsafe.Pointer(_p0)), uintptr(_p1), uintptr(len(buf)), 0, 0)
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func symlinkat(oldpath string, newdirfd int, newpath string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(oldpath)
+	if err != nil {
+		return
+	}
+	var _p1 *byte
+	_p1, err = BytePtrFromString(newpath)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall(SYS_SYMLINKAT, uintptr(unsafe.Pointer(_p0)), uintptr(newdirfd), uintptr(unsafe.Pointer(_p1)))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func unlinkat(dirfd int, path string, flags int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall(SYS_UNLINKAT, uintptr(dirfd), uintptr(unsafe.Pointer(_p0)), uintptr(flags))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func utimensat(dirfd int, path string, times *[2]Timespec, flag int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall6(SYS_UTIMENSAT, uintptr(dirfd), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(times)), uintptr(flag), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Getcwd(buf []byte) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(buf) > 0 {
+		_p0 = unsafe.Pointer(&buf[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_GETCWD, uintptr(_p0), uintptr(len(buf)), 0)
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func wait4(pid int, wstatus *_C_int, options int, rusage *Rusage) (wpid int, err error) {
+	r0, _, e1 := Syscall6(SYS_WAIT4, uintptr(pid), uintptr(unsafe.Pointer(wstatus)), uintptr(options), uintptr(unsafe.Pointer(rusage)), 0, 0)
+	wpid = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func ptrace(request int, pid int, addr uintptr, data uintptr) (err error) {
+	_, _, e1 := Syscall6(SYS_PTRACE, uintptr(request), uintptr(pid), uintptr(addr), uintptr(data), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func reboot(magic1 uint, magic2 uint, cmd int, arg string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(arg)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall6(SYS_REBOOT, uintptr(magic1), uintptr(magic2), uintptr(cmd), uintptr(unsafe.Pointer(_p0)), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func mount(source string, target string, fstype string, flags uintptr, data *byte) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(source)
+	if err != nil {
+		return
+	}
+	var _p1 *byte
+	_p1, err = BytePtrFromString(target)
+	if err != nil {
+		return
+	}
+	var _p2 *byte
+	_p2, err = BytePtrFromString(fstype)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall6(SYS_MOUNT, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(_p1)), uintptr(unsafe.Pointer(_p2)), uintptr(flags), uintptr(unsafe.Pointer(data)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Acct(path string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall(SYS_ACCT, uintptr(unsafe.Pointer(_p0)), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Adjtimex(buf *Timex) (state int, err error) {
+	r0, _, e1 := Syscall(SYS_ADJTIMEX, uintptr(unsafe.Pointer(buf)), 0, 0)
+	state = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Chdir(path string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall(SYS_CHDIR, uintptr(unsafe.Pointer(_p0)), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Chroot(path string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall(SYS_CHROOT, uintptr(unsafe.Pointer(_p0)), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Close(fd int) (err error) {
+	_, _, e1 := Syscall(SYS_CLOSE, uintptr(fd), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Dup(oldfd int) (fd int, err error) {
+	r0, _, e1 := Syscall(SYS_DUP, uintptr(oldfd), 0, 0)
+	fd = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Dup3(oldfd int, newfd int, flags int) (err error) {
+	_, _, e1 := Syscall(SYS_DUP3, uintptr(oldfd), uintptr(newfd), uintptr(flags))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func EpollCreate1(flag int) (fd int, err error) {
+	r0, _, e1 := RawSyscall(SYS_EPOLL_CREATE1, uintptr(flag), 0, 0)
+	fd = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func EpollCtl(epfd int, op int, fd int, event *EpollEvent) (err error) {
+	_, _, e1 := RawSyscall6(SYS_EPOLL_CTL, uintptr(epfd), uintptr(op), uintptr(fd), uintptr(unsafe.Pointer(event)), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fallocate(fd int, mode uint32, off int64, len int64) (err error) {
+	_, _, e1 := Syscall6(SYS_FALLOCATE, uintptr(fd), uintptr(mode), uintptr(off), uintptr(len), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fchdir(fd int) (err error) {
+	_, _, e1 := Syscall(SYS_FCHDIR, uintptr(fd), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fchmod(fd int, mode uint32) (err error) {
+	_, _, e1 := Syscall(SYS_FCHMOD, uintptr(fd), uintptr(mode), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fchownat(dirfd int, path string, uid int, gid int, flags int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall6(SYS_FCHOWNAT, uintptr(dirfd), uintptr(unsafe.Pointer(_p0)), uintptr(uid), uintptr(gid), uintptr(flags), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func fcntl(fd int, cmd int, arg int) (val int, err error) {
+	r0, _, e1 := Syscall(SYS_FCNTL, uintptr(fd), uintptr(cmd), uintptr(arg))
+	val = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fdatasync(fd int) (err error) {
+	_, _, e1 := Syscall(SYS_FDATASYNC, uintptr(fd), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Flock(fd int, how int) (err error) {
+	_, _, e1 := Syscall(SYS_FLOCK, uintptr(fd), uintptr(how), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fsync(fd int) (err error) {
+	_, _, e1 := Syscall(SYS_FSYNC, uintptr(fd), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Getdents(fd int, buf []byte) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(buf) > 0 {
+		_p0 = unsafe.Pointer(&buf[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_GETDENTS64, uintptr(fd), uintptr(_p0), uintptr(len(buf)))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Getpgid(pid int) (pgid int, err error) {
+	r0, _, e1 := RawSyscall(SYS_GETPGID, uintptr(pid), 0, 0)
+	pgid = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Getpid() (pid int) {
+	r0, _ := rawSyscallNoError(SYS_GETPID, 0, 0, 0)
+	pid = int(r0)
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Getppid() (ppid int) {
+	r0, _ := rawSyscallNoError(SYS_GETPPID, 0, 0, 0)
+	ppid = int(r0)
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Getpriority(which int, who int) (prio int, err error) {
+	r0, _, e1 := Syscall(SYS_GETPRIORITY, uintptr(which), uintptr(who), 0)
+	prio = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Getrusage(who int, rusage *Rusage) (err error) {
+	_, _, e1 := RawSyscall(SYS_GETRUSAGE, uintptr(who), uintptr(unsafe.Pointer(rusage)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Gettid() (tid int) {
+	r0, _ := rawSyscallNoError(SYS_GETTID, 0, 0, 0)
+	tid = int(r0)
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Getxattr(path string, attr string, dest []byte) (sz int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	var _p1 *byte
+	_p1, err = BytePtrFromString(attr)
+	if err != nil {
+		return
+	}
+	var _p2 unsafe.Pointer
+	if len(dest) > 0 {
+		_p2 = unsafe.Pointer(&dest[0])
+	} else {
+		_p2 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall6(SYS_GETXATTR, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(_p1)), uintptr(_p2), uintptr(len(dest)), 0, 0)
+	sz = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func InotifyAddWatch(fd int, pathname string, mask uint32) (watchdesc int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(pathname)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_INOTIFY_ADD_WATCH, uintptr(fd), uintptr(unsafe.Pointer(_p0)), uintptr(mask))
+	watchdesc = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func InotifyInit1(flags int) (fd int, err error) {
+	r0, _, e1 := RawSyscall(SYS_INOTIFY_INIT1, uintptr(flags), 0, 0)
+	fd = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func InotifyRmWatch(fd int, watchdesc uint32) (success int, err error) {
+	r0, _, e1 := RawSyscall(SYS_INOTIFY_RM_WATCH, uintptr(fd), uintptr(watchdesc), 0)
+	success = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Kill(pid int, sig Signal) (err error) {
+	_, _, e1 := RawSyscall(SYS_KILL, uintptr(pid), uintptr(sig), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Klogctl(typ int, buf []byte) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(buf) > 0 {
+		_p0 = unsafe.Pointer(&buf[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_SYSLOG, uintptr(typ), uintptr(_p0), uintptr(len(buf)))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Listxattr(path string, dest []byte) (sz int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	var _p1 unsafe.Pointer
+	if len(dest) > 0 {
+		_p1 = unsafe.Pointer(&dest[0])
+	} else {
+		_p1 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_LISTXATTR, uintptr(unsafe.Pointer(_p0)), uintptr(_p1), uintptr(len(dest)))
+	sz = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Mkdirat(dirfd int, path string, mode uint32) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall(SYS_MKDIRAT, uintptr(dirfd), uintptr(unsafe.Pointer(_p0)), uintptr(mode))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Mknodat(dirfd int, path string, mode uint32, dev int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall6(SYS_MKNODAT, uintptr(dirfd), uintptr(unsafe.Pointer(_p0)), uintptr(mode), uintptr(dev), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Nanosleep(time *Timespec, leftover *Timespec) (err error) {
+	_, _, e1 := Syscall(SYS_NANOSLEEP, uintptr(unsafe.Pointer(time)), uintptr(unsafe.Pointer(leftover)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func PivotRoot(newroot string, putold string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(newroot)
+	if err != nil {
+		return
+	}
+	var _p1 *byte
+	_p1, err = BytePtrFromString(putold)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall(SYS_PIVOT_ROOT, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(_p1)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func prlimit(pid int, resource int, newlimit *Rlimit, old *Rlimit) (err error) {
+	_, _, e1 := RawSyscall6(SYS_PRLIMIT64, uintptr(pid), uintptr(resource), uintptr(unsafe.Pointer(newlimit)), uintptr(unsafe.Pointer(old)), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func read(fd int, p []byte) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(p) > 0 {
+		_p0 = unsafe.Pointer(&p[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_READ, uintptr(fd), uintptr(_p0), uintptr(len(p)))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Removexattr(path string, attr string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	var _p1 *byte
+	_p1, err = BytePtrFromString(attr)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall(SYS_REMOVEXATTR, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(_p1)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Setdomainname(p []byte) (err error) {
+	var _p0 unsafe.Pointer
+	if len(p) > 0 {
+		_p0 = unsafe.Pointer(&p[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	_, _, e1 := Syscall(SYS_SETDOMAINNAME, uintptr(_p0), uintptr(len(p)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Sethostname(p []byte) (err error) {
+	var _p0 unsafe.Pointer
+	if len(p) > 0 {
+		_p0 = unsafe.Pointer(&p[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	_, _, e1 := Syscall(SYS_SETHOSTNAME, uintptr(_p0), uintptr(len(p)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Setpgid(pid int, pgid int) (err error) {
+	_, _, e1 := RawSyscall(SYS_SETPGID, uintptr(pid), uintptr(pgid), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Setsid() (pid int, err error) {
+	r0, _, e1 := RawSyscall(SYS_SETSID, 0, 0, 0)
+	pid = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Settimeofday(tv *Timeval) (err error) {
+	_, _, e1 := RawSyscall(SYS_SETTIMEOFDAY, uintptr(unsafe.Pointer(tv)), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Setpriority(which int, who int, prio int) (err error) {
+	_, _, e1 := Syscall(SYS_SETPRIORITY, uintptr(which), uintptr(who), uintptr(prio))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Setxattr(path string, attr string, data []byte, flags int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	var _p1 *byte
+	_p1, err = BytePtrFromString(attr)
+	if err != nil {
+		return
+	}
+	var _p2 unsafe.Pointer
+	if len(data) > 0 {
+		_p2 = unsafe.Pointer(&data[0])
+	} else {
+		_p2 = unsafe.Pointer(&_zero)
+	}
+	_, _, e1 := Syscall6(SYS_SETXATTR, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(_p1)), uintptr(_p2), uintptr(len(data)), uintptr(flags), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Sync() {
+	Syscall(SYS_SYNC, 0, 0, 0)
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Sysinfo(info *Sysinfo_t) (err error) {
+	_, _, e1 := RawSyscall(SYS_SYSINFO, uintptr(unsafe.Pointer(info)), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Tee(rfd int, wfd int, len int, flags int) (n int64, err error) {
+	r0, _, e1 := Syscall6(SYS_TEE, uintptr(rfd), uintptr(wfd), uintptr(len), uintptr(flags), 0, 0)
+	n = int64(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Tgkill(tgid int, tid int, sig Signal) (err error) {
+	_, _, e1 := RawSyscall(SYS_TGKILL, uintptr(tgid), uintptr(tid), uintptr(sig))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Times(tms *Tms) (ticks uintptr, err error) {
+	r0, _, e1 := RawSyscall(SYS_TIMES, uintptr(unsafe.Pointer(tms)), 0, 0)
+	ticks = uintptr(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Umask(mask int) (oldmask int) {
+	r0, _ := rawSyscallNoError(SYS_UMASK, uintptr(mask), 0, 0)
+	oldmask = int(r0)
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Uname(buf *Utsname) (err error) {
+	_, _, e1 := RawSyscall(SYS_UNAME, uintptr(unsafe.Pointer(buf)), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Unmount(target string, flags int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(target)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall(SYS_UMOUNT2, uintptr(unsafe.Pointer(_p0)), uintptr(flags), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Unshare(flags int) (err error) {
+	_, _, e1 := Syscall(SYS_UNSHARE, uintptr(flags), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func write(fd int, p []byte) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(p) > 0 {
+		_p0 = unsafe.Pointer(&p[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_WRITE, uintptr(fd), uintptr(_p0), uintptr(len(p)))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func exitThread(code int) (err error) {
+	_, _, e1 := Syscall(SYS_EXIT, uintptr(code), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func readlen(fd int, p *byte, np int) (n int, err error) {
+	r0, _, e1 := Syscall(SYS_READ, uintptr(fd), uintptr(unsafe.Pointer(p)), uintptr(np))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func writelen(fd int, p *byte, np int) (n int, err error) {
+	r0, _, e1 := Syscall(SYS_WRITE, uintptr(fd), uintptr(unsafe.Pointer(p)), uintptr(np))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func munmap(addr uintptr, length uintptr) (err error) {
+	_, _, e1 := Syscall(SYS_MUNMAP, uintptr(addr), uintptr(length), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Madvise(b []byte, advice int) (err error) {
+	var _p0 unsafe.Pointer
+	if len(b) > 0 {
+		_p0 = unsafe.Pointer(&b[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	_, _, e1 := Syscall(SYS_MADVISE, uintptr(_p0), uintptr(len(b)), uintptr(advice))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Mprotect(b []byte, prot int) (err error) {
+	var _p0 unsafe.Pointer
+	if len(b) > 0 {
+		_p0 = unsafe.Pointer(&b[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	_, _, e1 := Syscall(SYS_MPROTECT, uintptr(_p0), uintptr(len(b)), uintptr(prot))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Mlock(b []byte) (err error) {
+	var _p0 unsafe.Pointer
+	if len(b) > 0 {
+		_p0 = unsafe.Pointer(&b[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	_, _, e1 := Syscall(SYS_MLOCK, uintptr(_p0), uintptr(len(b)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Munlock(b []byte) (err error) {
+	var _p0 unsafe.Pointer
+	if len(b) > 0 {
+		_p0 = unsafe.Pointer(&b[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	_, _, e1 := Syscall(SYS_MUNLOCK, uintptr(_p0), uintptr(len(b)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Mlockall(flags int) (err error) {
+	_, _, e1 := Syscall(SYS_MLOCKALL, uintptr(flags), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Munlockall() (err error) {
+	_, _, e1 := Syscall(SYS_MUNLOCKALL, 0, 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Dup2(oldfd int, newfd int) (err error) {
+	_, _, e1 := Syscall(SYS_DUP2, uintptr(oldfd), uintptr(newfd), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func EpollCreate(size int) (fd int, err error) {
+	r0, _, e1 := RawSyscall(SYS_EPOLL_CREATE, uintptr(size), 0, 0)
+	fd = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fchown(fd int, uid int, gid int) (err error) {
+	_, _, e1 := Syscall(SYS_FCHOWN, uintptr(fd), uintptr(uid), uintptr(gid))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fstat(fd int, stat *Stat_t) (err error) {
+	_, _, e1 := Syscall(SYS_FSTAT, uintptr(fd), uintptr(unsafe.Pointer(stat)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fstatfs(fd int, buf *Statfs_t) (err error) {
+	_, _, e1 := Syscall(SYS_FSTATFS, uintptr(fd), uintptr(unsafe.Pointer(buf)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Ftruncate(fd int, length int64) (err error) {
+	_, _, e1 := Syscall(SYS_FTRUNCATE, uintptr(fd), uintptr(length), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Getegid() (egid int) {
+	r0, _ := rawSyscallNoError(SYS_GETEGID, 0, 0, 0)
+	egid = int(r0)
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Geteuid() (euid int) {
+	r0, _ := rawSyscallNoError(SYS_GETEUID, 0, 0, 0)
+	euid = int(r0)
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Getgid() (gid int) {
+	r0, _ := rawSyscallNoError(SYS_GETGID, 0, 0, 0)
+	gid = int(r0)
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Getrlimit(resource int, rlim *Rlimit) (err error) {
+	_, _, e1 := RawSyscall(SYS_GETRLIMIT, uintptr(resource), uintptr(unsafe.Pointer(rlim)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Getuid() (uid int) {
+	r0, _ := rawSyscallNoError(SYS_GETUID, 0, 0, 0)
+	uid = int(r0)
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func InotifyInit() (fd int, err error) {
+	r0, _, e1 := RawSyscall(SYS_INOTIFY_INIT, 0, 0, 0)
+	fd = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Ioperm(from int, num int, on int) (err error) {
+	_, _, e1 := Syscall(SYS_IOPERM, uintptr(from), uintptr(num), uintptr(on))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Iopl(level int) (err error) {
+	_, _, e1 := Syscall(SYS_IOPL, uintptr(level), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Listen(s int, n int) (err error) {
+	_, _, e1 := Syscall(SYS_LISTEN, uintptr(s), uintptr(n), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Pause() (err error) {
+	_, _, e1 := Syscall(SYS_PAUSE, 0, 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func pread(fd int, p []byte, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(p) > 0 {
+		_p0 = unsafe.Pointer(&p[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall6(SYS_PREAD64, uintptr(fd), uintptr(_p0), uintptr(len(p)), uintptr(offset), 0, 0)
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func pwrite(fd int, p []byte, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(p) > 0 {
+		_p0 = unsafe.Pointer(&p[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall6(SYS_PWRITE64, uintptr(fd), uintptr(_p0), uintptr(len(p)), uintptr(offset), 0, 0)
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Renameat(olddirfd int, oldpath string, newdirfd int, newpath string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(oldpath)
+	if err != nil {
+		return
+	}
+	var _p1 *byte
+	_p1, err = BytePtrFromString(newpath)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall6(SYS_RENAMEAT, uintptr(olddirfd), uintptr(unsafe.Pointer(_p0)), uintptr(newdirfd), uintptr(unsafe.Pointer(_p1)), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Seek(fd int, offset int64, whence int) (off int64, err error) {
+	r0, _, e1 := Syscall(SYS_LSEEK, uintptr(fd), uintptr(offset), uintptr(whence))
+	off = int64(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Select(nfd int, r *FdSet, w *FdSet, e *FdSet, timeout *Timeval) (n int, err error) {
+	r0, _, e1 := Syscall6(SYS_SELECT, uintptr(nfd), uintptr(unsafe.Pointer(r)), uintptr(unsafe.Pointer(w)), uintptr(unsafe.Pointer(e)), uintptr(unsafe.Pointer(timeout)), 0)
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func sendfile(outfd int, infd int, offset *int64, count int) (written int, err error) {
+	r0, _, e1 := Syscall6(SYS_SENDFILE, uintptr(outfd), uintptr(infd), uintptr(unsafe.Pointer(offset)), uintptr(count), 0, 0)
+	written = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Setfsgid(gid int) (err error) {
+	_, _, e1 := Syscall(SYS_SETFSGID, uintptr(gid), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Setfsuid(uid int) (err error) {
+	_, _, e1 := Syscall(SYS_SETFSUID, uintptr(uid), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Setrlimit(resource int, rlim *Rlimit) (err error) {
+	_, _, e1 := RawSyscall(SYS_SETRLIMIT, uintptr(resource), uintptr(unsafe.Pointer(rlim)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Shutdown(fd int, how int) (err error) {
+	_, _, e1 := Syscall(SYS_SHUTDOWN, uintptr(fd), uintptr(how), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Splice(rfd int, roff *int64, wfd int, woff *int64, len int, flags int) (n int64, err error) {
+	r0, _, e1 := Syscall6(SYS_SPLICE, uintptr(rfd), uintptr(unsafe.Pointer(roff)), uintptr(wfd), uintptr(unsafe.Pointer(woff)), uintptr(len), uintptr(flags))
+	n = int64(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Statfs(path string, buf *Statfs_t) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall(SYS_STATFS, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(buf)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func SyncFileRange(fd int, off int64, n int64, flags int) (err error) {
+	_, _, e1 := Syscall6(SYS_SYNC_FILE_RANGE, uintptr(fd), uintptr(off), uintptr(n), uintptr(flags), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Truncate(path string, length int64) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall(SYS_TRUNCATE, uintptr(unsafe.Pointer(_p0)), uintptr(length), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Ustat(dev int, ubuf *Ustat_t) (err error) {
+	_, _, e1 := Syscall(SYS_USTAT, uintptr(dev), uintptr(unsafe.Pointer(ubuf)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func accept4(s int, rsa *RawSockaddrAny, addrlen *_Socklen, flags int) (fd int, err error) {
+	r0, _, e1 := Syscall6(SYS_ACCEPT4, uintptr(s), uintptr(unsafe.Pointer(rsa)), uintptr(unsafe.Pointer(addrlen)), uintptr(flags), 0, 0)
+	fd = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func bind(s int, addr unsafe.Pointer, addrlen _Socklen) (err error) {
+	_, _, e1 := Syscall(SYS_BIND, uintptr(s), uintptr(addr), uintptr(addrlen))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func connect(s int, addr unsafe.Pointer, addrlen _Socklen) (err error) {
+	_, _, e1 := Syscall(SYS_CONNECT, uintptr(s), uintptr(addr), uintptr(addrlen))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func fstatat(fd int, path string, stat *Stat_t, flags int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall6(SYS_NEWFSTATAT, uintptr(fd), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(stat)), uintptr(flags), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func getgroups(n int, list *_Gid_t) (nn int, err error) {
+	r0, _, e1 := RawSyscall(SYS_GETGROUPS, uintptr(n), uintptr(unsafe.Pointer(list)), 0)
+	nn = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func getsockopt(s int, level int, name int, val unsafe.Pointer, vallen *_Socklen) (err error) {
+	_, _, e1 := Syscall6(SYS_GETSOCKOPT, uintptr(s), uintptr(level), uintptr(name), uintptr(val), uintptr(unsafe.Pointer(vallen)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func setsockopt(s int, level int, name int, val unsafe.Pointer, vallen uintptr) (err error) {
+	_, _, e1 := Syscall6(SYS_SETSOCKOPT, uintptr(s), uintptr(level), uintptr(name), uintptr(val), uintptr(vallen), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func socket(domain int, typ int, proto int) (fd int, err error) {
+	r0, _, e1 := RawSyscall(SYS_SOCKET, uintptr(domain), uintptr(typ), uintptr(proto))
+	fd = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func socketpair(domain int, typ int, proto int, fd *[2]int32) (err error) {
+	_, _, e1 := RawSyscall6(SYS_SOCKETPAIR, uintptr(domain), uintptr(typ), uintptr(proto), uintptr(unsafe.Pointer(fd)), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func getpeername(fd int, rsa *RawSockaddrAny, addrlen *_Socklen) (err error) {
+	_, _, e1 := RawSyscall(SYS_GETPEERNAME, uintptr(fd), uintptr(unsafe.Pointer(rsa)), uintptr(unsafe.Pointer(addrlen)))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func getsockname(fd int, rsa *RawSockaddrAny, addrlen *_Socklen) (err error) {
+	_, _, e1 := RawSyscall(SYS_GETSOCKNAME, uintptr(fd), uintptr(unsafe.Pointer(rsa)), uintptr(unsafe.Pointer(addrlen)))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func recvfrom(fd int, p []byte, flags int, from *RawSockaddrAny, fromlen *_Socklen) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(p) > 0 {
+		_p0 = unsafe.Pointer(&p[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall6(SYS_RECVFROM, uintptr(fd), uintptr(_p0), uintptr(len(p)), uintptr(flags), uintptr(unsafe.Pointer(from)), uintptr(unsafe.Pointer(fromlen)))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func sendto(s int, buf []byte, flags int, to unsafe.Pointer, addrlen _Socklen) (err error) {
+	var _p0 unsafe.Pointer
+	if len(buf) > 0 {
+		_p0 = unsafe.Pointer(&buf[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	_, _, e1 := Syscall6(SYS_SENDTO, uintptr(s), uintptr(_p0), uintptr(len(buf)), uintptr(flags), uintptr(to), uintptr(addrlen))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func recvmsg(s int, msg *Msghdr, flags int) (n int, err error) {
+	r0, _, e1 := Syscall(SYS_RECVMSG, uintptr(s), uintptr(unsafe.Pointer(msg)), uintptr(flags))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func sendmsg(s int, msg *Msghdr, flags int) (n int, err error) {
+	r0, _, e1 := Syscall(SYS_SENDMSG, uintptr(s), uintptr(unsafe.Pointer(msg)), uintptr(flags))
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func mmap(addr uintptr, length uintptr, prot int, flags int, fd int, offset int64) (xaddr uintptr, err error) {
+	r0, _, e1 := Syscall6(SYS_MMAP, uintptr(addr), uintptr(length), uintptr(prot), uintptr(flags), uintptr(fd), uintptr(offset))
+	xaddr = uintptr(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(events) > 0 {
+		_p0 = unsafe.Pointer(&events[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall6(SYS_EPOLL_WAIT, uintptr(epfd), uintptr(_p0), uintptr(len(events)), uintptr(msec), 0, 0)
+	n = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func futimesat(dirfd int, path string, times *[2]Timeval) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall(SYS_FUTIMESAT, uintptr(dirfd), uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(times)))
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Utime(path string, buf *Utimbuf) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall(SYS_UTIME, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(buf)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func utimes(path string, times *[2]Timeval) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	_, _, e1 := Syscall(SYS_UTIMES, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(times)), 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
diff --git a/contrib/go/_std_1.18/src/syscall/zsysnum_darwin_amd64.go b/contrib/go/_std_1.19/src/syscall/zsysnum_darwin_amd64.go
index 08e003f292..08e003f292 100644
--- a/contrib/go/_std_1.18/src/syscall/zsysnum_darwin_amd64.go
+++ b/contrib/go/_std_1.19/src/syscall/zsysnum_darwin_amd64.go
diff --git a/contrib/go/_std_1.18/src/syscall/zsysnum_linux_amd64.go b/contrib/go/_std_1.19/src/syscall/zsysnum_linux_amd64.go
index 576c7c36a6..576c7c36a6 100644
--- a/contrib/go/_std_1.18/src/syscall/zsysnum_linux_amd64.go
+++ b/contrib/go/_std_1.19/src/syscall/zsysnum_linux_amd64.go
diff --git a/contrib/go/_std_1.18/src/syscall/ztypes_darwin_amd64.go b/contrib/go/_std_1.19/src/syscall/ztypes_darwin_amd64.go
index 551edc7025..551edc7025 100644
--- a/contrib/go/_std_1.18/src/syscall/ztypes_darwin_amd64.go
+++ b/contrib/go/_std_1.19/src/syscall/ztypes_darwin_amd64.go
diff --git a/contrib/go/_std_1.18/src/syscall/ztypes_linux_amd64.go b/contrib/go/_std_1.19/src/syscall/ztypes_linux_amd64.go
index 1bab13bf43..1bab13bf43 100644
--- a/contrib/go/_std_1.18/src/syscall/ztypes_linux_amd64.go
+++ b/contrib/go/_std_1.19/src/syscall/ztypes_linux_amd64.go
diff --git a/contrib/go/_std_1.19/src/text/template/doc.go b/contrib/go/_std_1.19/src/text/template/doc.go
new file mode 100644
index 0000000000..58cc97371b
--- /dev/null
+++ b/contrib/go/_std_1.19/src/text/template/doc.go
@@ -0,0 +1,464 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package template implements data-driven templates for generating textual output.
+
+To generate HTML output, see package html/template, which has the same interface
+as this package but automatically secures HTML output against certain attacks.
+
+Templates are executed by applying them to a data structure. Annotations in the
+template refer to elements of the data structure (typically a field of a struct
+or a key in a map) to control execution and derive values to be displayed.
+Execution of the template walks the structure and sets the cursor, represented
+by a period '.' and called "dot", to the value at the current location in the
+structure as execution proceeds.
+
+The input text for a template is UTF-8-encoded text in any format.
+"Actions"--data evaluations or control structures--are delimited by
+"{{" and "}}"; all text outside actions is copied to the output unchanged.
+
+Once parsed, a template may be executed safely in parallel, although if parallel
+executions share a Writer the output may be interleaved.
+
+Here is a trivial example that prints "17 items are made of wool".
+
+	type Inventory struct {
+		Material string
+		Count    uint
+	}
+	sweaters := Inventory{"wool", 17}
+	tmpl, err := template.New("test").Parse("{{.Count}} items are made of {{.Material}}")
+	if err != nil { panic(err) }
+	err = tmpl.Execute(os.Stdout, sweaters)
+	if err != nil { panic(err) }
+
+More intricate examples appear below.
+
+Text and spaces
+
+By default, all text between actions is copied verbatim when the template is
+executed. For example, the string " items are made of " in the example above
+appears on standard output when the program is run.
+
+However, to aid in formatting template source code, if an action's left
+delimiter (by default "{{") is followed immediately by a minus sign and white
+space, all trailing white space is trimmed from the immediately preceding text.
+Similarly, if the right delimiter ("}}") is preceded by white space and a minus
+sign, all leading white space is trimmed from the immediately following text.
+In these trim markers, the white space must be present:
+"{{- 3}}" is like "{{3}}" but trims the immediately preceding text, while
+"{{-3}}" parses as an action containing the number -3.
+
+For instance, when executing the template whose source is
+
+	"{{23 -}} < {{- 45}}"
+
+the generated output would be
+
+	"23<45"
+
+For this trimming, the definition of white space characters is the same as in Go:
+space, horizontal tab, carriage return, and newline.
+
+Actions
+
+Here is the list of actions. "Arguments" and "pipelines" are evaluations of
+data, defined in detail in the corresponding sections that follow.
+
+*/
+//	{{/* a comment */}}
+//	{{- /* a comment with white space trimmed from preceding and following text */ -}}
+//		A comment; discarded. May contain newlines.
+//		Comments do not nest and must start and end at the
+//		delimiters, as shown here.
+/*
+
+	{{pipeline}}
+		The default textual representation (the same as would be
+		printed by fmt.Print) of the value of the pipeline is copied
+		to the output.
+
+	{{if pipeline}} T1 {{end}}
+		If the value of the pipeline is empty, no output is generated;
+		otherwise, T1 is executed. The empty values are false, 0, any
+		nil pointer or interface value, and any array, slice, map, or
+		string of length zero.
+		Dot is unaffected.
+
+	{{if pipeline}} T1 {{else}} T0 {{end}}
+		If the value of the pipeline is empty, T0 is executed;
+		otherwise, T1 is executed. Dot is unaffected.
+
+	{{if pipeline}} T1 {{else if pipeline}} T0 {{end}}
+		To simplify the appearance of if-else chains, the else action
+		of an if may include another if directly; the effect is exactly
+		the same as writing
+			{{if pipeline}} T1 {{else}}{{if pipeline}} T0 {{end}}{{end}}
+
+	{{range pipeline}} T1 {{end}}
+		The value of the pipeline must be an array, slice, map, or channel.
+		If the value of the pipeline has length zero, nothing is output;
+		otherwise, dot is set to the successive elements of the array,
+		slice, or map and T1 is executed. If the value is a map and the
+		keys are of basic type with a defined order, the elements will be
+		visited in sorted key order.
+
+	{{range pipeline}} T1 {{else}} T0 {{end}}
+		The value of the pipeline must be an array, slice, map, or channel.
+		If the value of the pipeline has length zero, dot is unaffected and
+		T0 is executed; otherwise, dot is set to the successive elements
+		of the array, slice, or map and T1 is executed.
+
+	{{break}}
+		The innermost {{range pipeline}} loop is ended early, stopping the
+		current iteration and bypassing all remaining iterations.
+
+	{{continue}}
+		The current iteration of the innermost {{range pipeline}} loop is
+		stopped, and the loop starts the next iteration.
+
+	{{template "name"}}
+		The template with the specified name is executed with nil data.
+
+	{{template "name" pipeline}}
+		The template with the specified name is executed with dot set
+		to the value of the pipeline.
+
+	{{block "name" pipeline}} T1 {{end}}
+		A block is shorthand for defining a template
+			{{define "name"}} T1 {{end}}
+		and then executing it in place
+			{{template "name" pipeline}}
+		The typical use is to define a set of root templates that are
+		then customized by redefining the block templates within.
+
+	{{with pipeline}} T1 {{end}}
+		If the value of the pipeline is empty, no output is generated;
+		otherwise, dot is set to the value of the pipeline and T1 is
+		executed.
+
+	{{with pipeline}} T1 {{else}} T0 {{end}}
+		If the value of the pipeline is empty, dot is unaffected and T0
+		is executed; otherwise, dot is set to the value of the pipeline
+		and T1 is executed.
+
+Arguments
+
+An argument is a simple value, denoted by one of the following.
+
+	- A boolean, string, character, integer, floating-point, imaginary
+	  or complex constant in Go syntax. These behave like Go's untyped
+	  constants. Note that, as in Go, whether a large integer constant
+	  overflows when assigned or passed to a function can depend on whether
+	  the host machine's ints are 32 or 64 bits.
+	- The keyword nil, representing an untyped Go nil.
+	- The character '.' (period):
+		.
+	  The result is the value of dot.
+	- A variable name, which is a (possibly empty) alphanumeric string
+	  preceded by a dollar sign, such as
+		$piOver2
+	  or
+		$
+	  The result is the value of the variable.
+	  Variables are described below.
+	- The name of a field of the data, which must be a struct, preceded
+	  by a period, such as
+		.Field
+	  The result is the value of the field. Field invocations may be
+	  chained:
+	    .Field1.Field2
+	  Fields can also be evaluated on variables, including chaining:
+	    $x.Field1.Field2
+	- The name of a key of the data, which must be a map, preceded
+	  by a period, such as
+		.Key
+	  The result is the map element value indexed by the key.
+	  Key invocations may be chained and combined with fields to any
+	  depth:
+	    .Field1.Key1.Field2.Key2
+	  Although the key must be an alphanumeric identifier, unlike with
+	  field names they do not need to start with an upper case letter.
+	  Keys can also be evaluated on variables, including chaining:
+	    $x.key1.key2
+	- The name of a niladic method of the data, preceded by a period,
+	  such as
+		.Method
+	  The result is the value of invoking the method with dot as the
+	  receiver, dot.Method(). Such a method must have one return value (of
+	  any type) or two return values, the second of which is an error.
+	  If it has two and the returned error is non-nil, execution terminates
+	  and an error is returned to the caller as the value of Execute.
+	  Method invocations may be chained and combined with fields and keys
+	  to any depth:
+	    .Field1.Key1.Method1.Field2.Key2.Method2
+	  Methods can also be evaluated on variables, including chaining:
+	    $x.Method1.Field
+	- The name of a niladic function, such as
+		fun
+	  The result is the value of invoking the function, fun(). The return
+	  types and values behave as in methods. Functions and function
+	  names are described below.
+	- A parenthesized instance of one the above, for grouping. The result
+	  may be accessed by a field or map key invocation.
+		print (.F1 arg1) (.F2 arg2)
+		(.StructValuedMethod "arg").Field
+
+Arguments may evaluate to any type; if they are pointers the implementation
+automatically indirects to the base type when required.
+If an evaluation yields a function value, such as a function-valued
+field of a struct, the function is not invoked automatically, but it
+can be used as a truth value for an if action and the like. To invoke
+it, use the call function, defined below.
+
+Pipelines
+
+A pipeline is a possibly chained sequence of "commands". A command is a simple
+value (argument) or a function or method call, possibly with multiple arguments:
+
+	Argument
+		The result is the value of evaluating the argument.
+	.Method [Argument...]
+		The method can be alone or the last element of a chain but,
+		unlike methods in the middle of a chain, it can take arguments.
+		The result is the value of calling the method with the
+		arguments:
+			dot.Method(Argument1, etc.)
+	functionName [Argument...]
+		The result is the value of calling the function associated
+		with the name:
+			function(Argument1, etc.)
+		Functions and function names are described below.
+
+A pipeline may be "chained" by separating a sequence of commands with pipeline
+characters '|'. In a chained pipeline, the result of each command is
+passed as the last argument of the following command. The output of the final
+command in the pipeline is the value of the pipeline.
+
+The output of a command will be either one value or two values, the second of
+which has type error. If that second value is present and evaluates to
+non-nil, execution terminates and the error is returned to the caller of
+Execute.
+
+Variables
+
+A pipeline inside an action may initialize a variable to capture the result.
+The initialization has syntax
+
+	$variable := pipeline
+
+where $variable is the name of the variable. An action that declares a
+variable produces no output.
+
+Variables previously declared can also be assigned, using the syntax
+
+	$variable = pipeline
+
+If a "range" action initializes a variable, the variable is set to the
+successive elements of the iteration. Also, a "range" may declare two
+variables, separated by a comma:
+
+	range $index, $element := pipeline
+
+in which case $index and $element are set to the successive values of the
+array/slice index or map key and element, respectively. Note that if there is
+only one variable, it is assigned the element; this is opposite to the
+convention in Go range clauses.
+
+A variable's scope extends to the "end" action of the control structure ("if",
+"with", or "range") in which it is declared, or to the end of the template if
+there is no such control structure. A template invocation does not inherit
+variables from the point of its invocation.
+
+When execution begins, $ is set to the data argument passed to Execute, that is,
+to the starting value of dot.
+
+Examples
+
+Here are some example one-line templates demonstrating pipelines and variables.
+All produce the quoted word "output":
+
+	{{"\"output\""}}
+		A string constant.
+	{{`"output"`}}
+		A raw string constant.
+	{{printf "%q" "output"}}
+		A function call.
+	{{"output" | printf "%q"}}
+		A function call whose final argument comes from the previous
+		command.
+	{{printf "%q" (print "out" "put")}}
+		A parenthesized argument.
+	{{"put" | printf "%s%s" "out" | printf "%q"}}
+		A more elaborate call.
+	{{"output" | printf "%s" | printf "%q"}}
+		A longer chain.
+	{{with "output"}}{{printf "%q" .}}{{end}}
+		A with action using dot.
+	{{with $x := "output" | printf "%q"}}{{$x}}{{end}}
+		A with action that creates and uses a variable.
+	{{with $x := "output"}}{{printf "%q" $x}}{{end}}
+		A with action that uses the variable in another action.
+	{{with $x := "output"}}{{$x | printf "%q"}}{{end}}
+		The same, but pipelined.
+
+Functions
+
+During execution functions are found in two function maps: first in the
+template, then in the global function map. By default, no functions are defined
+in the template but the Funcs method can be used to add them.
+
+Predefined global functions are named as follows.
+
+	and
+		Returns the boolean AND of its arguments by returning the
+		first empty argument or the last argument. That is,
+		"and x y" behaves as "if x then y else x."
+		Evaluation proceeds through the arguments left to right
+		and returns when the result is determined.
+	call
+		Returns the result of calling the first argument, which
+		must be a function, with the remaining arguments as parameters.
+		Thus "call .X.Y 1 2" is, in Go notation, dot.X.Y(1, 2) where
+		Y is a func-valued field, map entry, or the like.
+		The first argument must be the result of an evaluation
+		that yields a value of function type (as distinct from
+		a predefined function such as print). The function must
+		return either one or two result values, the second of which
+		is of type error. If the arguments don't match the function
+		or the returned error value is non-nil, execution stops.
+	html
+		Returns the escaped HTML equivalent of the textual
+		representation of its arguments. This function is unavailable
+		in html/template, with a few exceptions.
+	index
+		Returns the result of indexing its first argument by the
+		following arguments. Thus "index x 1 2 3" is, in Go syntax,
+		x[1][2][3]. Each indexed item must be a map, slice, or array.
+	slice
+		slice returns the result of slicing its first argument by the
+		remaining arguments. Thus "slice x 1 2" is, in Go syntax, x[1:2],
+		while "slice x" is x[:], "slice x 1" is x[1:], and "slice x 1 2 3"
+		is x[1:2:3]. The first argument must be a string, slice, or array.
+	js
+		Returns the escaped JavaScript equivalent of the textual
+		representation of its arguments.
+	len
+		Returns the integer length of its argument.
+	not
+		Returns the boolean negation of its single argument.
+	or
+		Returns the boolean OR of its arguments by returning the
+		first non-empty argument or the last argument, that is,
+		"or x y" behaves as "if x then x else y".
+		Evaluation proceeds through the arguments left to right
+		and returns when the result is determined.
+	print
+		An alias for fmt.Sprint
+	printf
+		An alias for fmt.Sprintf
+	println
+		An alias for fmt.Sprintln
+	urlquery
+		Returns the escaped value of the textual representation of
+		its arguments in a form suitable for embedding in a URL query.
+		This function is unavailable in html/template, with a few
+		exceptions.
+
+The boolean functions take any zero value to be false and a non-zero
+value to be true.
+
+There is also a set of binary comparison operators defined as
+functions:
+
+	eq
+		Returns the boolean truth of arg1 == arg2
+	ne
+		Returns the boolean truth of arg1 != arg2
+	lt
+		Returns the boolean truth of arg1 < arg2
+	le
+		Returns the boolean truth of arg1 <= arg2
+	gt
+		Returns the boolean truth of arg1 > arg2
+	ge
+		Returns the boolean truth of arg1 >= arg2
+
+For simpler multi-way equality tests, eq (only) accepts two or more
+arguments and compares the second and subsequent to the first,
+returning in effect
+
+	arg1==arg2 || arg1==arg3 || arg1==arg4 ...
+
+(Unlike with || in Go, however, eq is a function call and all the
+arguments will be evaluated.)
+
+The comparison functions work on any values whose type Go defines as
+comparable. For basic types such as integers, the rules are relaxed:
+size and exact type are ignored, so any integer value, signed or unsigned,
+may be compared with any other integer value. (The arithmetic value is compared,
+not the bit pattern, so all negative integers are less than all unsigned integers.)
+However, as usual, one may not compare an int with a float32 and so on.
+
+Associated templates
+
+Each template is named by a string specified when it is created. Also, each
+template is associated with zero or more other templates that it may invoke by
+name; such associations are transitive and form a name space of templates.
+
+A template may use a template invocation to instantiate another associated
+template; see the explanation of the "template" action above. The name must be
+that of a template associated with the template that contains the invocation.
+
+Nested template definitions
+
+When parsing a template, another template may be defined and associated with the
+template being parsed. Template definitions must appear at the top level of the
+template, much like global variables in a Go program.
+
+The syntax of such definitions is to surround each template declaration with a
+"define" and "end" action.
+
+The define action names the template being created by providing a string
+constant. Here is a simple example:
+
+	`{{define "T1"}}ONE{{end}}
+	{{define "T2"}}TWO{{end}}
+	{{define "T3"}}{{template "T1"}} {{template "T2"}}{{end}}
+	{{template "T3"}}`
+
+This defines two templates, T1 and T2, and a third T3 that invokes the other two
+when it is executed. Finally it invokes T3. If executed this template will
+produce the text
+
+	ONE TWO
+
+By construction, a template may reside in only one association. If it's
+necessary to have a template addressable from multiple associations, the
+template definition must be parsed multiple times to create distinct *Template
+values, or must be copied with the Clone or AddParseTree method.
+
+Parse may be called multiple times to assemble the various associated templates;
+see the ParseFiles and ParseGlob functions and methods for simple ways to parse
+related templates stored in files.
+
+A template may be executed directly or through ExecuteTemplate, which executes
+an associated template identified by name. To invoke our example above, we
+might write,
+
+	err := tmpl.Execute(os.Stdout, "no data needed")
+	if err != nil {
+		log.Fatalf("execution failed: %s", err)
+	}
+
+or to invoke a particular template explicitly by name,
+
+	err := tmpl.ExecuteTemplate(os.Stdout, "T2", "no data needed")
+	if err != nil {
+		log.Fatalf("execution failed: %s", err)
+	}
+
+*/
+package template
diff --git a/contrib/go/_std_1.18/src/text/template/exec.go b/contrib/go/_std_1.19/src/text/template/exec.go
index 37984cf91a..37984cf91a 100644
--- a/contrib/go/_std_1.18/src/text/template/exec.go
+++ b/contrib/go/_std_1.19/src/text/template/exec.go
diff --git a/contrib/go/_std_1.19/src/text/template/funcs.go b/contrib/go/_std_1.19/src/text/template/funcs.go
new file mode 100644
index 0000000000..390d47ebbb
--- /dev/null
+++ b/contrib/go/_std_1.19/src/text/template/funcs.go
@@ -0,0 +1,777 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package template
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+	"net/url"
+	"reflect"
+	"strings"
+	"sync"
+	"unicode"
+	"unicode/utf8"
+)
+
+// FuncMap is the type of the map defining the mapping from names to functions.
+// Each function must have either a single return value, or two return values of
+// which the second has type error. In that case, if the second (error)
+// return value evaluates to non-nil during execution, execution terminates and
+// Execute returns that error.
+//
+// Errors returned by Execute wrap the underlying error; call errors.As to
+// uncover them.
+//
+// When template execution invokes a function with an argument list, that list
+// must be assignable to the function's parameter types. Functions meant to
+// apply to arguments of arbitrary type can use parameters of type interface{} or
+// of type reflect.Value. Similarly, functions meant to return a result of arbitrary
+// type can return interface{} or reflect.Value.
+type FuncMap map[string]any
+
+// builtins returns the FuncMap.
+// It is not a global variable so the linker can dead code eliminate
+// more when this isn't called. See golang.org/issue/36021.
+// TODO: revert this back to a global map once golang.org/issue/2559 is fixed.
+func builtins() FuncMap {
+	return FuncMap{
+		"and":      and,
+		"call":     call,
+		"html":     HTMLEscaper,
+		"index":    index,
+		"slice":    slice,
+		"js":       JSEscaper,
+		"len":      length,
+		"not":      not,
+		"or":       or,
+		"print":    fmt.Sprint,
+		"printf":   fmt.Sprintf,
+		"println":  fmt.Sprintln,
+		"urlquery": URLQueryEscaper,
+
+		// Comparisons
+		"eq": eq, // ==
+		"ge": ge, // >=
+		"gt": gt, // >
+		"le": le, // <=
+		"lt": lt, // <
+		"ne": ne, // !=
+	}
+}
+
+var builtinFuncsOnce struct {
+	sync.Once
+	v map[string]reflect.Value
+}
+
+// builtinFuncsOnce lazily computes & caches the builtinFuncs map.
+// TODO: revert this back to a global map once golang.org/issue/2559 is fixed.
+func builtinFuncs() map[string]reflect.Value {
+	builtinFuncsOnce.Do(func() {
+		builtinFuncsOnce.v = createValueFuncs(builtins())
+	})
+	return builtinFuncsOnce.v
+}
+
+// createValueFuncs turns a FuncMap into a map[string]reflect.Value
+func createValueFuncs(funcMap FuncMap) map[string]reflect.Value {
+	m := make(map[string]reflect.Value)
+	addValueFuncs(m, funcMap)
+	return m
+}
+
+// addValueFuncs adds to values the functions in funcs, converting them to reflect.Values.
+func addValueFuncs(out map[string]reflect.Value, in FuncMap) {
+	for name, fn := range in {
+		if !goodName(name) {
+			panic(fmt.Errorf("function name %q is not a valid identifier", name))
+		}
+		v := reflect.ValueOf(fn)
+		if v.Kind() != reflect.Func {
+			panic("value for " + name + " not a function")
+		}
+		if !goodFunc(v.Type()) {
+			panic(fmt.Errorf("can't install method/function %q with %d results", name, v.Type().NumOut()))
+		}
+		out[name] = v
+	}
+}
+
+// addFuncs adds to values the functions in funcs. It does no checking of the input -
+// call addValueFuncs first.
+func addFuncs(out, in FuncMap) {
+	for name, fn := range in {
+		out[name] = fn
+	}
+}
+
+// goodFunc reports whether the function or method has the right result signature.
+func goodFunc(typ reflect.Type) bool {
+	// We allow functions with 1 result or 2 results where the second is an error.
+	switch {
+	case typ.NumOut() == 1:
+		return true
+	case typ.NumOut() == 2 && typ.Out(1) == errorType:
+		return true
+	}
+	return false
+}
+
+// goodName reports whether the function name is a valid identifier.
+func goodName(name string) bool {
+	if name == "" {
+		return false
+	}
+	for i, r := range name {
+		switch {
+		case r == '_':
+		case i == 0 && !unicode.IsLetter(r):
+			return false
+		case !unicode.IsLetter(r) && !unicode.IsDigit(r):
+			return false
+		}
+	}
+	return true
+}
+
+// findFunction looks for a function in the template, and global map.
+func findFunction(name string, tmpl *Template) (v reflect.Value, isBuiltin, ok bool) {
+	if tmpl != nil && tmpl.common != nil {
+		tmpl.muFuncs.RLock()
+		defer tmpl.muFuncs.RUnlock()
+		if fn := tmpl.execFuncs[name]; fn.IsValid() {
+			return fn, false, true
+		}
+	}
+	if fn := builtinFuncs()[name]; fn.IsValid() {
+		return fn, true, true
+	}
+	return reflect.Value{}, false, false
+}
+
+// prepareArg checks if value can be used as an argument of type argType, and
+// converts an invalid value to appropriate zero if possible.
+func prepareArg(value reflect.Value, argType reflect.Type) (reflect.Value, error) {
+	if !value.IsValid() {
+		if !canBeNil(argType) {
+			return reflect.Value{}, fmt.Errorf("value is nil; should be of type %s", argType)
+		}
+		value = reflect.Zero(argType)
+	}
+	if value.Type().AssignableTo(argType) {
+		return value, nil
+	}
+	if intLike(value.Kind()) && intLike(argType.Kind()) && value.Type().ConvertibleTo(argType) {
+		value = value.Convert(argType)
+		return value, nil
+	}
+	return reflect.Value{}, fmt.Errorf("value has type %s; should be %s", value.Type(), argType)
+}
+
+func intLike(typ reflect.Kind) bool {
+	switch typ {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return true
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return true
+	}
+	return false
+}
+
+// indexArg checks if a reflect.Value can be used as an index, and converts it to int if possible.
+func indexArg(index reflect.Value, cap int) (int, error) {
+	var x int64
+	switch index.Kind() {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		x = index.Int()
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		x = int64(index.Uint())
+	case reflect.Invalid:
+		return 0, fmt.Errorf("cannot index slice/array with nil")
+	default:
+		return 0, fmt.Errorf("cannot index slice/array with type %s", index.Type())
+	}
+	if x < 0 || int(x) < 0 || int(x) > cap {
+		return 0, fmt.Errorf("index out of range: %d", x)
+	}
+	return int(x), nil
+}
+
+// Indexing.
+
+// index returns the result of indexing its first argument by the following
+// arguments. Thus "index x 1 2 3" is, in Go syntax, x[1][2][3]. Each
+// indexed item must be a map, slice, or array.
+func index(item reflect.Value, indexes ...reflect.Value) (reflect.Value, error) {
+	item = indirectInterface(item)
+	if !item.IsValid() {
+		return reflect.Value{}, fmt.Errorf("index of untyped nil")
+	}
+	for _, index := range indexes {
+		index = indirectInterface(index)
+		var isNil bool
+		if item, isNil = indirect(item); isNil {
+			return reflect.Value{}, fmt.Errorf("index of nil pointer")
+		}
+		switch item.Kind() {
+		case reflect.Array, reflect.Slice, reflect.String:
+			x, err := indexArg(index, item.Len())
+			if err != nil {
+				return reflect.Value{}, err
+			}
+			item = item.Index(x)
+		case reflect.Map:
+			index, err := prepareArg(index, item.Type().Key())
+			if err != nil {
+				return reflect.Value{}, err
+			}
+			if x := item.MapIndex(index); x.IsValid() {
+				item = x
+			} else {
+				item = reflect.Zero(item.Type().Elem())
+			}
+		case reflect.Invalid:
+			// the loop holds invariant: item.IsValid()
+			panic("unreachable")
+		default:
+			return reflect.Value{}, fmt.Errorf("can't index item of type %s", item.Type())
+		}
+	}
+	return item, nil
+}
+
+// Slicing.
+
+// slice returns the result of slicing its first argument by the remaining
+// arguments. Thus "slice x 1 2" is, in Go syntax, x[1:2], while "slice x"
+// is x[:], "slice x 1" is x[1:], and "slice x 1 2 3" is x[1:2:3]. The first
+// argument must be a string, slice, or array.
+func slice(item reflect.Value, indexes ...reflect.Value) (reflect.Value, error) {
+	item = indirectInterface(item)
+	if !item.IsValid() {
+		return reflect.Value{}, fmt.Errorf("slice of untyped nil")
+	}
+	if len(indexes) > 3 {
+		return reflect.Value{}, fmt.Errorf("too many slice indexes: %d", len(indexes))
+	}
+	var cap int
+	switch item.Kind() {
+	case reflect.String:
+		if len(indexes) == 3 {
+			return reflect.Value{}, fmt.Errorf("cannot 3-index slice a string")
+		}
+		cap = item.Len()
+	case reflect.Array, reflect.Slice:
+		cap = item.Cap()
+	default:
+		return reflect.Value{}, fmt.Errorf("can't slice item of type %s", item.Type())
+	}
+	// set default values for cases item[:], item[i:].
+	idx := [3]int{0, item.Len()}
+	for i, index := range indexes {
+		x, err := indexArg(index, cap)
+		if err != nil {
+			return reflect.Value{}, err
+		}
+		idx[i] = x
+	}
+	// given item[i:j], make sure i <= j.
+	if idx[0] > idx[1] {
+		return reflect.Value{}, fmt.Errorf("invalid slice index: %d > %d", idx[0], idx[1])
+	}
+	if len(indexes) < 3 {
+		return item.Slice(idx[0], idx[1]), nil
+	}
+	// given item[i:j:k], make sure i <= j <= k.
+	if idx[1] > idx[2] {
+		return reflect.Value{}, fmt.Errorf("invalid slice index: %d > %d", idx[1], idx[2])
+	}
+	return item.Slice3(idx[0], idx[1], idx[2]), nil
+}
+
+// Length
+
+// length returns the length of the item, with an error if it has no defined length.
+func length(item reflect.Value) (int, error) {
+	item, isNil := indirect(item)
+	if isNil {
+		return 0, fmt.Errorf("len of nil pointer")
+	}
+	switch item.Kind() {
+	case reflect.Array, reflect.Chan, reflect.Map, reflect.Slice, reflect.String:
+		return item.Len(), nil
+	}
+	return 0, fmt.Errorf("len of type %s", item.Type())
+}
+
+// Function invocation
+
+// call returns the result of evaluating the first argument as a function.
+// The function must return 1 result, or 2 results, the second of which is an error.
+func call(fn reflect.Value, args ...reflect.Value) (reflect.Value, error) {
+	fn = indirectInterface(fn)
+	if !fn.IsValid() {
+		return reflect.Value{}, fmt.Errorf("call of nil")
+	}
+	typ := fn.Type()
+	if typ.Kind() != reflect.Func {
+		return reflect.Value{}, fmt.Errorf("non-function of type %s", typ)
+	}
+	if !goodFunc(typ) {
+		return reflect.Value{}, fmt.Errorf("function called with %d args; should be 1 or 2", typ.NumOut())
+	}
+	numIn := typ.NumIn()
+	var dddType reflect.Type
+	if typ.IsVariadic() {
+		if len(args) < numIn-1 {
+			return reflect.Value{}, fmt.Errorf("wrong number of args: got %d want at least %d", len(args), numIn-1)
+		}
+		dddType = typ.In(numIn - 1).Elem()
+	} else {
+		if len(args) != numIn {
+			return reflect.Value{}, fmt.Errorf("wrong number of args: got %d want %d", len(args), numIn)
+		}
+	}
+	argv := make([]reflect.Value, len(args))
+	for i, arg := range args {
+		arg = indirectInterface(arg)
+		// Compute the expected type. Clumsy because of variadics.
+		argType := dddType
+		if !typ.IsVariadic() || i < numIn-1 {
+			argType = typ.In(i)
+		}
+
+		var err error
+		if argv[i], err = prepareArg(arg, argType); err != nil {
+			return reflect.Value{}, fmt.Errorf("arg %d: %w", i, err)
+		}
+	}
+	return safeCall(fn, argv)
+}
+
+// safeCall runs fun.Call(args), and returns the resulting value and error, if
+// any. If the call panics, the panic value is returned as an error.
+func safeCall(fun reflect.Value, args []reflect.Value) (val reflect.Value, err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			if e, ok := r.(error); ok {
+				err = e
+			} else {
+				err = fmt.Errorf("%v", r)
+			}
+		}
+	}()
+	ret := fun.Call(args)
+	if len(ret) == 2 && !ret[1].IsNil() {
+		return ret[0], ret[1].Interface().(error)
+	}
+	return ret[0], nil
+}
+
+// Boolean logic.
+
+func truth(arg reflect.Value) bool {
+	t, _ := isTrue(indirectInterface(arg))
+	return t
+}
+
+// and computes the Boolean AND of its arguments, returning
+// the first false argument it encounters, or the last argument.
+func and(arg0 reflect.Value, args ...reflect.Value) reflect.Value {
+	panic("unreachable") // implemented as a special case in evalCall
+}
+
+// or computes the Boolean OR of its arguments, returning
+// the first true argument it encounters, or the last argument.
+func or(arg0 reflect.Value, args ...reflect.Value) reflect.Value {
+	panic("unreachable") // implemented as a special case in evalCall
+}
+
+// not returns the Boolean negation of its argument.
+func not(arg reflect.Value) bool {
+	return !truth(arg)
+}
+
+// Comparison.
+
+// TODO: Perhaps allow comparison between signed and unsigned integers.
+
+var (
+	errBadComparisonType = errors.New("invalid type for comparison")
+	errBadComparison     = errors.New("incompatible types for comparison")
+	errNoComparison      = errors.New("missing argument for comparison")
+)
+
+type kind int
+
+const (
+	invalidKind kind = iota
+	boolKind
+	complexKind
+	intKind
+	floatKind
+	stringKind
+	uintKind
+)
+
+func basicKind(v reflect.Value) (kind, error) {
+	switch v.Kind() {
+	case reflect.Bool:
+		return boolKind, nil
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return intKind, nil
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return uintKind, nil
+	case reflect.Float32, reflect.Float64:
+		return floatKind, nil
+	case reflect.Complex64, reflect.Complex128:
+		return complexKind, nil
+	case reflect.String:
+		return stringKind, nil
+	}
+	return invalidKind, errBadComparisonType
+}
+
+// isNil returns true if v is the zero reflect.Value, or nil of its type.
+func isNil(v reflect.Value) bool {
+	if v == zero {
+		return true
+	}
+	switch v.Kind() {
+	case reflect.Chan, reflect.Func, reflect.Interface, reflect.Map, reflect.Pointer, reflect.Slice:
+		return v.IsNil()
+	}
+	return false
+}
+
+// canCompare reports whether v1 and v2 are both the same kind, or one is nil.
+// Called only when dealing with nillable types, or there's about to be an error.
+func canCompare(v1, v2 reflect.Value) bool {
+	k1 := v1.Kind()
+	k2 := v2.Kind()
+	if k1 == k2 {
+		return true
+	}
+	// We know the type can be compared to nil.
+	return k1 == reflect.Invalid || k2 == reflect.Invalid
+}
+
+// eq evaluates the comparison a == b || a == c || ...
+func eq(arg1 reflect.Value, arg2 ...reflect.Value) (bool, error) {
+	arg1 = indirectInterface(arg1)
+	if len(arg2) == 0 {
+		return false, errNoComparison
+	}
+	k1, _ := basicKind(arg1)
+	for _, arg := range arg2 {
+		arg = indirectInterface(arg)
+		k2, _ := basicKind(arg)
+		truth := false
+		if k1 != k2 {
+			// Special case: Can compare integer values regardless of type's sign.
+			switch {
+			case k1 == intKind && k2 == uintKind:
+				truth = arg1.Int() >= 0 && uint64(arg1.Int()) == arg.Uint()
+			case k1 == uintKind && k2 == intKind:
+				truth = arg.Int() >= 0 && arg1.Uint() == uint64(arg.Int())
+			default:
+				if arg1 != zero && arg != zero {
+					return false, errBadComparison
+				}
+			}
+		} else {
+			switch k1 {
+			case boolKind:
+				truth = arg1.Bool() == arg.Bool()
+			case complexKind:
+				truth = arg1.Complex() == arg.Complex()
+			case floatKind:
+				truth = arg1.Float() == arg.Float()
+			case intKind:
+				truth = arg1.Int() == arg.Int()
+			case stringKind:
+				truth = arg1.String() == arg.String()
+			case uintKind:
+				truth = arg1.Uint() == arg.Uint()
+			default:
+				if !canCompare(arg1, arg) {
+					return false, fmt.Errorf("non-comparable types %s: %v, %s: %v", arg1, arg1.Type(), arg.Type(), arg)
+				}
+				if isNil(arg1) || isNil(arg) {
+					truth = isNil(arg) == isNil(arg1)
+				} else {
+					if !arg.Type().Comparable() {
+						return false, fmt.Errorf("non-comparable type %s: %v", arg, arg.Type())
+					}
+					truth = arg1.Interface() == arg.Interface()
+				}
+			}
+		}
+		if truth {
+			return true, nil
+		}
+	}
+	return false, nil
+}
+
+// ne evaluates the comparison a != b.
+func ne(arg1, arg2 reflect.Value) (bool, error) {
+	// != is the inverse of ==.
+	equal, err := eq(arg1, arg2)
+	return !equal, err
+}
+
+// lt evaluates the comparison a < b.
+func lt(arg1, arg2 reflect.Value) (bool, error) {
+	arg1 = indirectInterface(arg1)
+	k1, err := basicKind(arg1)
+	if err != nil {
+		return false, err
+	}
+	arg2 = indirectInterface(arg2)
+	k2, err := basicKind(arg2)
+	if err != nil {
+		return false, err
+	}
+	truth := false
+	if k1 != k2 {
+		// Special case: Can compare integer values regardless of type's sign.
+		switch {
+		case k1 == intKind && k2 == uintKind:
+			truth = arg1.Int() < 0 || uint64(arg1.Int()) < arg2.Uint()
+		case k1 == uintKind && k2 == intKind:
+			truth = arg2.Int() >= 0 && arg1.Uint() < uint64(arg2.Int())
+		default:
+			return false, errBadComparison
+		}
+	} else {
+		switch k1 {
+		case boolKind, complexKind:
+			return false, errBadComparisonType
+		case floatKind:
+			truth = arg1.Float() < arg2.Float()
+		case intKind:
+			truth = arg1.Int() < arg2.Int()
+		case stringKind:
+			truth = arg1.String() < arg2.String()
+		case uintKind:
+			truth = arg1.Uint() < arg2.Uint()
+		default:
+			panic("invalid kind")
+		}
+	}
+	return truth, nil
+}
+
+// le evaluates the comparison <= b.
+func le(arg1, arg2 reflect.Value) (bool, error) {
+	// <= is < or ==.
+	lessThan, err := lt(arg1, arg2)
+	if lessThan || err != nil {
+		return lessThan, err
+	}
+	return eq(arg1, arg2)
+}
+
+// gt evaluates the comparison a > b.
+func gt(arg1, arg2 reflect.Value) (bool, error) {
+	// > is the inverse of <=.
+	lessOrEqual, err := le(arg1, arg2)
+	if err != nil {
+		return false, err
+	}
+	return !lessOrEqual, nil
+}
+
+// ge evaluates the comparison a >= b.
+func ge(arg1, arg2 reflect.Value) (bool, error) {
+	// >= is the inverse of <.
+	lessThan, err := lt(arg1, arg2)
+	if err != nil {
+		return false, err
+	}
+	return !lessThan, nil
+}
+
+// HTML escaping.
+
+var (
+	htmlQuot = []byte("&#34;") // shorter than "&quot;"
+	htmlApos = []byte("&#39;") // shorter than "&apos;" and apos was not in HTML until HTML5
+	htmlAmp  = []byte("&amp;")
+	htmlLt   = []byte("&lt;")
+	htmlGt   = []byte("&gt;")
+	htmlNull = []byte("\uFFFD")
+)
+
+// HTMLEscape writes to w the escaped HTML equivalent of the plain text data b.
+func HTMLEscape(w io.Writer, b []byte) {
+	last := 0
+	for i, c := range b {
+		var html []byte
+		switch c {
+		case '\000':
+			html = htmlNull
+		case '"':
+			html = htmlQuot
+		case '\'':
+			html = htmlApos
+		case '&':
+			html = htmlAmp
+		case '<':
+			html = htmlLt
+		case '>':
+			html = htmlGt
+		default:
+			continue
+		}
+		w.Write(b[last:i])
+		w.Write(html)
+		last = i + 1
+	}
+	w.Write(b[last:])
+}
+
+// HTMLEscapeString returns the escaped HTML equivalent of the plain text data s.
+func HTMLEscapeString(s string) string {
+	// Avoid allocation if we can.
+	if !strings.ContainsAny(s, "'\"&<>\000") {
+		return s
+	}
+	var b bytes.Buffer
+	HTMLEscape(&b, []byte(s))
+	return b.String()
+}
+
+// HTMLEscaper returns the escaped HTML equivalent of the textual
+// representation of its arguments.
+func HTMLEscaper(args ...any) string {
+	return HTMLEscapeString(evalArgs(args))
+}
+
+// JavaScript escaping.
+
+var (
+	jsLowUni = []byte(`\u00`)
+	hex      = []byte("0123456789ABCDEF")
+
+	jsBackslash = []byte(`\\`)
+	jsApos      = []byte(`\'`)
+	jsQuot      = []byte(`\"`)
+	jsLt        = []byte(`\u003C`)
+	jsGt        = []byte(`\u003E`)
+	jsAmp       = []byte(`\u0026`)
+	jsEq        = []byte(`\u003D`)
+)
+
+// JSEscape writes to w the escaped JavaScript equivalent of the plain text data b.
+func JSEscape(w io.Writer, b []byte) {
+	last := 0
+	for i := 0; i < len(b); i++ {
+		c := b[i]
+
+		if !jsIsSpecial(rune(c)) {
+			// fast path: nothing to do
+			continue
+		}
+		w.Write(b[last:i])
+
+		if c < utf8.RuneSelf {
+			// Quotes, slashes and angle brackets get quoted.
+			// Control characters get written as \u00XX.
+			switch c {
+			case '\\':
+				w.Write(jsBackslash)
+			case '\'':
+				w.Write(jsApos)
+			case '"':
+				w.Write(jsQuot)
+			case '<':
+				w.Write(jsLt)
+			case '>':
+				w.Write(jsGt)
+			case '&':
+				w.Write(jsAmp)
+			case '=':
+				w.Write(jsEq)
+			default:
+				w.Write(jsLowUni)
+				t, b := c>>4, c&0x0f
+				w.Write(hex[t : t+1])
+				w.Write(hex[b : b+1])
+			}
+		} else {
+			// Unicode rune.
+			r, size := utf8.DecodeRune(b[i:])
+			if unicode.IsPrint(r) {
+				w.Write(b[i : i+size])
+			} else {
+				fmt.Fprintf(w, "\\u%04X", r)
+			}
+			i += size - 1
+		}
+		last = i + 1
+	}
+	w.Write(b[last:])
+}
+
+// JSEscapeString returns the escaped JavaScript equivalent of the plain text data s.
+func JSEscapeString(s string) string {
+	// Avoid allocation if we can.
+	if strings.IndexFunc(s, jsIsSpecial) < 0 {
+		return s
+	}
+	var b bytes.Buffer
+	JSEscape(&b, []byte(s))
+	return b.String()
+}
+
+func jsIsSpecial(r rune) bool {
+	switch r {
+	case '\\', '\'', '"', '<', '>', '&', '=':
+		return true
+	}
+	return r < ' ' || utf8.RuneSelf <= r
+}
+
+// JSEscaper returns the escaped JavaScript equivalent of the textual
+// representation of its arguments.
+func JSEscaper(args ...any) string {
+	return JSEscapeString(evalArgs(args))
+}
+
+// URLQueryEscaper returns the escaped value of the textual representation of
+// its arguments in a form suitable for embedding in a URL query.
+func URLQueryEscaper(args ...any) string {
+	return url.QueryEscape(evalArgs(args))
+}
+
+// evalArgs formats the list of arguments into a string. It is therefore equivalent to
+//
+//	fmt.Sprint(args...)
+//
+// except that each argument is indirected (if a pointer), as required,
+// using the same rules as the default string evaluation during template
+// execution.
+func evalArgs(args []any) string {
+	ok := false
+	var s string
+	// Fast path for simple common case.
+	if len(args) == 1 {
+		s, ok = args[0].(string)
+	}
+	if !ok {
+		for i, arg := range args {
+			a, ok := printableValue(reflect.ValueOf(arg))
+			if ok {
+				args[i] = a
+			} // else let fmt do its thing
+		}
+		s = fmt.Sprint(args...)
+	}
+	return s
+}
diff --git a/contrib/go/_std_1.19/src/text/template/helper.go b/contrib/go/_std_1.19/src/text/template/helper.go
new file mode 100644
index 0000000000..48af3928b3
--- /dev/null
+++ b/contrib/go/_std_1.19/src/text/template/helper.go
@@ -0,0 +1,178 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Helper functions to make constructing templates easier.
+
+package template
+
+import (
+	"fmt"
+	"io/fs"
+	"os"
+	"path"
+	"path/filepath"
+)
+
+// Functions and methods to parse templates.
+
+// Must is a helper that wraps a call to a function returning (*Template, error)
+// and panics if the error is non-nil. It is intended for use in variable
+// initializations such as
+//
+//	var t = template.Must(template.New("name").Parse("text"))
+func Must(t *Template, err error) *Template {
+	if err != nil {
+		panic(err)
+	}
+	return t
+}
+
+// ParseFiles creates a new Template and parses the template definitions from
+// the named files. The returned template's name will have the base name and
+// parsed contents of the first file. There must be at least one file.
+// If an error occurs, parsing stops and the returned *Template is nil.
+//
+// When parsing multiple files with the same name in different directories,
+// the last one mentioned will be the one that results.
+// For instance, ParseFiles("a/foo", "b/foo") stores "b/foo" as the template
+// named "foo", while "a/foo" is unavailable.
+func ParseFiles(filenames ...string) (*Template, error) {
+	return parseFiles(nil, readFileOS, filenames...)
+}
+
+// ParseFiles parses the named files and associates the resulting templates with
+// t. If an error occurs, parsing stops and the returned template is nil;
+// otherwise it is t. There must be at least one file.
+// Since the templates created by ParseFiles are named by the base
+// names of the argument files, t should usually have the name of one
+// of the (base) names of the files. If it does not, depending on t's
+// contents before calling ParseFiles, t.Execute may fail. In that
+// case use t.ExecuteTemplate to execute a valid template.
+//
+// When parsing multiple files with the same name in different directories,
+// the last one mentioned will be the one that results.
+func (t *Template) ParseFiles(filenames ...string) (*Template, error) {
+	t.init()
+	return parseFiles(t, readFileOS, filenames...)
+}
+
+// parseFiles is the helper for the method and function. If the argument
+// template is nil, it is created from the first file.
+func parseFiles(t *Template, readFile func(string) (string, []byte, error), filenames ...string) (*Template, error) {
+	if len(filenames) == 0 {
+		// Not really a problem, but be consistent.
+		return nil, fmt.Errorf("template: no files named in call to ParseFiles")
+	}
+	for _, filename := range filenames {
+		name, b, err := readFile(filename)
+		if err != nil {
+			return nil, err
+		}
+		s := string(b)
+		// First template becomes return value if not already defined,
+		// and we use that one for subsequent New calls to associate
+		// all the templates together. Also, if this file has the same name
+		// as t, this file becomes the contents of t, so
+		//  t, err := New(name).Funcs(xxx).ParseFiles(name)
+		// works. Otherwise we create a new template associated with t.
+		var tmpl *Template
+		if t == nil {
+			t = New(name)
+		}
+		if name == t.Name() {
+			tmpl = t
+		} else {
+			tmpl = t.New(name)
+		}
+		_, err = tmpl.Parse(s)
+		if err != nil {
+			return nil, err
+		}
+	}
+	return t, nil
+}
+
+// ParseGlob creates a new Template and parses the template definitions from
+// the files identified by the pattern. The files are matched according to the
+// semantics of filepath.Match, and the pattern must match at least one file.
+// The returned template will have the (base) name and (parsed) contents of the
+// first file matched by the pattern. ParseGlob is equivalent to calling
+// ParseFiles with the list of files matched by the pattern.
+//
+// When parsing multiple files with the same name in different directories,
+// the last one mentioned will be the one that results.
+func ParseGlob(pattern string) (*Template, error) {
+	return parseGlob(nil, pattern)
+}
+
+// ParseGlob parses the template definitions in the files identified by the
+// pattern and associates the resulting templates with t. The files are matched
+// according to the semantics of filepath.Match, and the pattern must match at
+// least one file. ParseGlob is equivalent to calling t.ParseFiles with the
+// list of files matched by the pattern.
+//
+// When parsing multiple files with the same name in different directories,
+// the last one mentioned will be the one that results.
+func (t *Template) ParseGlob(pattern string) (*Template, error) {
+	t.init()
+	return parseGlob(t, pattern)
+}
+
+// parseGlob is the implementation of the function and method ParseGlob.
+func parseGlob(t *Template, pattern string) (*Template, error) {
+	filenames, err := filepath.Glob(pattern)
+	if err != nil {
+		return nil, err
+	}
+	if len(filenames) == 0 {
+		return nil, fmt.Errorf("template: pattern matches no files: %#q", pattern)
+	}
+	return parseFiles(t, readFileOS, filenames...)
+}
+
+// ParseFS is like ParseFiles or ParseGlob but reads from the file system fsys
+// instead of the host operating system's file system.
+// It accepts a list of glob patterns.
+// (Note that most file names serve as glob patterns matching only themselves.)
+func ParseFS(fsys fs.FS, patterns ...string) (*Template, error) {
+	return parseFS(nil, fsys, patterns)
+}
+
+// ParseFS is like ParseFiles or ParseGlob but reads from the file system fsys
+// instead of the host operating system's file system.
+// It accepts a list of glob patterns.
+// (Note that most file names serve as glob patterns matching only themselves.)
+func (t *Template) ParseFS(fsys fs.FS, patterns ...string) (*Template, error) {
+	t.init()
+	return parseFS(t, fsys, patterns)
+}
+
+func parseFS(t *Template, fsys fs.FS, patterns []string) (*Template, error) {
+	var filenames []string
+	for _, pattern := range patterns {
+		list, err := fs.Glob(fsys, pattern)
+		if err != nil {
+			return nil, err
+		}
+		if len(list) == 0 {
+			return nil, fmt.Errorf("template: pattern matches no files: %#q", pattern)
+		}
+		filenames = append(filenames, list...)
+	}
+	return parseFiles(t, readFileFS(fsys), filenames...)
+}
+
+func readFileOS(file string) (name string, b []byte, err error) {
+	name = filepath.Base(file)
+	b, err = os.ReadFile(file)
+	return
+}
+
+func readFileFS(fsys fs.FS) func(string) (string, []byte, error) {
+	return func(file string) (name string, b []byte, err error) {
+		name = path.Base(file)
+		b, err = fs.ReadFile(fsys, file)
+		return
+	}
+}
diff --git a/contrib/go/_std_1.19/src/text/template/option.go b/contrib/go/_std_1.19/src/text/template/option.go
new file mode 100644
index 0000000000..ea2fd80c06
--- /dev/null
+++ b/contrib/go/_std_1.19/src/text/template/option.go
@@ -0,0 +1,72 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file contains the code to handle template options.
+
+package template
+
+import "strings"
+
+// missingKeyAction defines how to respond to indexing a map with a key that is not present.
+type missingKeyAction int
+
+const (
+	mapInvalid   missingKeyAction = iota // Return an invalid reflect.Value.
+	mapZeroValue                         // Return the zero value for the map element.
+	mapError                             // Error out
+)
+
+type option struct {
+	missingKey missingKeyAction
+}
+
+// Option sets options for the template. Options are described by
+// strings, either a simple string or "key=value". There can be at
+// most one equals sign in an option string. If the option string
+// is unrecognized or otherwise invalid, Option panics.
+//
+// Known options:
+//
+// missingkey: Control the behavior during execution if a map is
+// indexed with a key that is not present in the map.
+//
+//	"missingkey=default" or "missingkey=invalid"
+//		The default behavior: Do nothing and continue execution.
+//		If printed, the result of the index operation is the string
+//		"<no value>".
+//	"missingkey=zero"
+//		The operation returns the zero value for the map type's element.
+//	"missingkey=error"
+//		Execution stops immediately with an error.
+func (t *Template) Option(opt ...string) *Template {
+	t.init()
+	for _, s := range opt {
+		t.setOption(s)
+	}
+	return t
+}
+
+func (t *Template) setOption(opt string) {
+	if opt == "" {
+		panic("empty option string")
+	}
+	// key=value
+	if key, value, ok := strings.Cut(opt, "="); ok {
+		switch key {
+		case "missingkey":
+			switch value {
+			case "invalid", "default":
+				t.option.missingKey = mapInvalid
+				return
+			case "zero":
+				t.option.missingKey = mapZeroValue
+				return
+			case "error":
+				t.option.missingKey = mapError
+				return
+			}
+		}
+	}
+	panic("unrecognized option: " + opt)
+}
diff --git a/contrib/go/_std_1.19/src/text/template/parse/lex.go b/contrib/go/_std_1.19/src/text/template/parse/lex.go
new file mode 100644
index 0000000000..29403dd947
--- /dev/null
+++ b/contrib/go/_std_1.19/src/text/template/parse/lex.go
@@ -0,0 +1,679 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package parse
+
+import (
+	"fmt"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+)
+
+// item represents a token or text string returned from the scanner.
+type item struct {
+	typ  itemType // The type of this item.
+	pos  Pos      // The starting position, in bytes, of this item in the input string.
+	val  string   // The value of this item.
+	line int      // The line number at the start of this item.
+}
+
+func (i item) String() string {
+	switch {
+	case i.typ == itemEOF:
+		return "EOF"
+	case i.typ == itemError:
+		return i.val
+	case i.typ > itemKeyword:
+		return fmt.Sprintf("<%s>", i.val)
+	case len(i.val) > 10:
+		return fmt.Sprintf("%.10q...", i.val)
+	}
+	return fmt.Sprintf("%q", i.val)
+}
+
+// itemType identifies the type of lex items.
+type itemType int
+
+const (
+	itemError        itemType = iota // error occurred; value is text of error
+	itemBool                         // boolean constant
+	itemChar                         // printable ASCII character; grab bag for comma etc.
+	itemCharConstant                 // character constant
+	itemComment                      // comment text
+	itemComplex                      // complex constant (1+2i); imaginary is just a number
+	itemAssign                       // equals ('=') introducing an assignment
+	itemDeclare                      // colon-equals (':=') introducing a declaration
+	itemEOF
+	itemField      // alphanumeric identifier starting with '.'
+	itemIdentifier // alphanumeric identifier not starting with '.'
+	itemLeftDelim  // left action delimiter
+	itemLeftParen  // '(' inside action
+	itemNumber     // simple number, including imaginary
+	itemPipe       // pipe symbol
+	itemRawString  // raw quoted string (includes quotes)
+	itemRightDelim // right action delimiter
+	itemRightParen // ')' inside action
+	itemSpace      // run of spaces separating arguments
+	itemString     // quoted string (includes quotes)
+	itemText       // plain text
+	itemVariable   // variable starting with '$', such as '$' or  '$1' or '$hello'
+	// Keywords appear after all the rest.
+	itemKeyword  // used only to delimit the keywords
+	itemBlock    // block keyword
+	itemBreak    // break keyword
+	itemContinue // continue keyword
+	itemDot      // the cursor, spelled '.'
+	itemDefine   // define keyword
+	itemElse     // else keyword
+	itemEnd      // end keyword
+	itemIf       // if keyword
+	itemNil      // the untyped nil constant, easiest to treat as a keyword
+	itemRange    // range keyword
+	itemTemplate // template keyword
+	itemWith     // with keyword
+)
+
+var key = map[string]itemType{
+	".":        itemDot,
+	"block":    itemBlock,
+	"break":    itemBreak,
+	"continue": itemContinue,
+	"define":   itemDefine,
+	"else":     itemElse,
+	"end":      itemEnd,
+	"if":       itemIf,
+	"range":    itemRange,
+	"nil":      itemNil,
+	"template": itemTemplate,
+	"with":     itemWith,
+}
+
+const eof = -1
+
+// Trimming spaces.
+// If the action begins "{{- " rather than "{{", then all space/tab/newlines
+// preceding the action are trimmed; conversely if it ends " -}}" the
+// leading spaces are trimmed. This is done entirely in the lexer; the
+// parser never sees it happen. We require an ASCII space (' ', \t, \r, \n)
+// to be present to avoid ambiguity with things like "{{-3}}". It reads
+// better with the space present anyway. For simplicity, only ASCII
+// does the job.
+const (
+	spaceChars    = " \t\r\n"  // These are the space characters defined by Go itself.
+	trimMarker    = '-'        // Attached to left/right delimiter, trims trailing spaces from preceding/following text.
+	trimMarkerLen = Pos(1 + 1) // marker plus space before or after
+)
+
+// stateFn represents the state of the scanner as a function that returns the next state.
+type stateFn func(*lexer) stateFn
+
+// lexer holds the state of the scanner.
+type lexer struct {
+	name        string    // the name of the input; used only for error reports
+	input       string    // the string being scanned
+	leftDelim   string    // start of action
+	rightDelim  string    // end of action
+	emitComment bool      // emit itemComment tokens.
+	pos         Pos       // current position in the input
+	start       Pos       // start position of this item
+	atEOF       bool      // we have hit the end of input and returned eof
+	items       chan item // channel of scanned items
+	parenDepth  int       // nesting depth of ( ) exprs
+	line        int       // 1+number of newlines seen
+	startLine   int       // start line of this item
+	breakOK     bool      // break keyword allowed
+	continueOK  bool      // continue keyword allowed
+}
+
+// next returns the next rune in the input.
+func (l *lexer) next() rune {
+	if int(l.pos) >= len(l.input) {
+		l.atEOF = true
+		return eof
+	}
+	r, w := utf8.DecodeRuneInString(l.input[l.pos:])
+	l.pos += Pos(w)
+	if r == '\n' {
+		l.line++
+	}
+	return r
+}
+
+// peek returns but does not consume the next rune in the input.
+func (l *lexer) peek() rune {
+	r := l.next()
+	l.backup()
+	return r
+}
+
+// backup steps back one rune.
+func (l *lexer) backup() {
+	if !l.atEOF && l.pos > 0 {
+		r, w := utf8.DecodeLastRuneInString(l.input[:l.pos])
+		l.pos -= Pos(w)
+		// Correct newline count.
+		if r == '\n' {
+			l.line--
+		}
+	}
+}
+
+// emit passes an item back to the client.
+func (l *lexer) emit(t itemType) {
+	l.items <- item{t, l.start, l.input[l.start:l.pos], l.startLine}
+	l.start = l.pos
+	l.startLine = l.line
+}
+
+// ignore skips over the pending input before this point.
+func (l *lexer) ignore() {
+	l.line += strings.Count(l.input[l.start:l.pos], "\n")
+	l.start = l.pos
+	l.startLine = l.line
+}
+
+// accept consumes the next rune if it's from the valid set.
+func (l *lexer) accept(valid string) bool {
+	if strings.ContainsRune(valid, l.next()) {
+		return true
+	}
+	l.backup()
+	return false
+}
+
+// acceptRun consumes a run of runes from the valid set.
+func (l *lexer) acceptRun(valid string) {
+	for strings.ContainsRune(valid, l.next()) {
+	}
+	l.backup()
+}
+
+// errorf returns an error token and terminates the scan by passing
+// back a nil pointer that will be the next state, terminating l.nextItem.
+func (l *lexer) errorf(format string, args ...any) stateFn {
+	l.items <- item{itemError, l.start, fmt.Sprintf(format, args...), l.startLine}
+	return nil
+}
+
+// nextItem returns the next item from the input.
+// Called by the parser, not in the lexing goroutine.
+func (l *lexer) nextItem() item {
+	return <-l.items
+}
+
+// drain drains the output so the lexing goroutine will exit.
+// Called by the parser, not in the lexing goroutine.
+func (l *lexer) drain() {
+	for range l.items {
+	}
+}
+
+// lex creates a new scanner for the input string.
+func lex(name, input, left, right string, emitComment, breakOK, continueOK bool) *lexer {
+	if left == "" {
+		left = leftDelim
+	}
+	if right == "" {
+		right = rightDelim
+	}
+	l := &lexer{
+		name:        name,
+		input:       input,
+		leftDelim:   left,
+		rightDelim:  right,
+		emitComment: emitComment,
+		breakOK:     breakOK,
+		continueOK:  continueOK,
+		items:       make(chan item),
+		line:        1,
+		startLine:   1,
+	}
+	go l.run()
+	return l
+}
+
+// run runs the state machine for the lexer.
+func (l *lexer) run() {
+	for state := lexText; state != nil; {
+		state = state(l)
+	}
+	close(l.items)
+}
+
+// state functions
+
+const (
+	leftDelim    = "{{"
+	rightDelim   = "}}"
+	leftComment  = "/*"
+	rightComment = "*/"
+)
+
+// lexText scans until an opening action delimiter, "{{".
+func lexText(l *lexer) stateFn {
+	if x := strings.Index(l.input[l.pos:], l.leftDelim); x >= 0 {
+		ldn := Pos(len(l.leftDelim))
+		l.pos += Pos(x)
+		trimLength := Pos(0)
+		if hasLeftTrimMarker(l.input[l.pos+ldn:]) {
+			trimLength = rightTrimLength(l.input[l.start:l.pos])
+		}
+		l.pos -= trimLength
+		if l.pos > l.start {
+			l.line += strings.Count(l.input[l.start:l.pos], "\n")
+			l.emit(itemText)
+		}
+		l.pos += trimLength
+		l.ignore()
+		return lexLeftDelim
+	}
+	l.pos = Pos(len(l.input))
+	// Correctly reached EOF.
+	if l.pos > l.start {
+		l.line += strings.Count(l.input[l.start:l.pos], "\n")
+		l.emit(itemText)
+	}
+	l.emit(itemEOF)
+	return nil
+}
+
+// rightTrimLength returns the length of the spaces at the end of the string.
+func rightTrimLength(s string) Pos {
+	return Pos(len(s) - len(strings.TrimRight(s, spaceChars)))
+}
+
+// atRightDelim reports whether the lexer is at a right delimiter, possibly preceded by a trim marker.
+func (l *lexer) atRightDelim() (delim, trimSpaces bool) {
+	if hasRightTrimMarker(l.input[l.pos:]) && strings.HasPrefix(l.input[l.pos+trimMarkerLen:], l.rightDelim) { // With trim marker.
+		return true, true
+	}
+	if strings.HasPrefix(l.input[l.pos:], l.rightDelim) { // Without trim marker.
+		return true, false
+	}
+	return false, false
+}
+
+// leftTrimLength returns the length of the spaces at the beginning of the string.
+func leftTrimLength(s string) Pos {
+	return Pos(len(s) - len(strings.TrimLeft(s, spaceChars)))
+}
+
+// lexLeftDelim scans the left delimiter, which is known to be present, possibly with a trim marker.
+func lexLeftDelim(l *lexer) stateFn {
+	l.pos += Pos(len(l.leftDelim))
+	trimSpace := hasLeftTrimMarker(l.input[l.pos:])
+	afterMarker := Pos(0)
+	if trimSpace {
+		afterMarker = trimMarkerLen
+	}
+	if strings.HasPrefix(l.input[l.pos+afterMarker:], leftComment) {
+		l.pos += afterMarker
+		l.ignore()
+		return lexComment
+	}
+	l.emit(itemLeftDelim)
+	l.pos += afterMarker
+	l.ignore()
+	l.parenDepth = 0
+	return lexInsideAction
+}
+
+// lexComment scans a comment. The left comment marker is known to be present.
+func lexComment(l *lexer) stateFn {
+	l.pos += Pos(len(leftComment))
+	i := strings.Index(l.input[l.pos:], rightComment)
+	if i < 0 {
+		return l.errorf("unclosed comment")
+	}
+	l.pos += Pos(i + len(rightComment))
+	delim, trimSpace := l.atRightDelim()
+	if !delim {
+		return l.errorf("comment ends before closing delimiter")
+	}
+	if l.emitComment {
+		l.emit(itemComment)
+	}
+	if trimSpace {
+		l.pos += trimMarkerLen
+	}
+	l.pos += Pos(len(l.rightDelim))
+	if trimSpace {
+		l.pos += leftTrimLength(l.input[l.pos:])
+	}
+	l.ignore()
+	return lexText
+}
+
+// lexRightDelim scans the right delimiter, which is known to be present, possibly with a trim marker.
+func lexRightDelim(l *lexer) stateFn {
+	trimSpace := hasRightTrimMarker(l.input[l.pos:])
+	if trimSpace {
+		l.pos += trimMarkerLen
+		l.ignore()
+	}
+	l.pos += Pos(len(l.rightDelim))
+	l.emit(itemRightDelim)
+	if trimSpace {
+		l.pos += leftTrimLength(l.input[l.pos:])
+		l.ignore()
+	}
+	return lexText
+}
+
+// lexInsideAction scans the elements inside action delimiters.
+func lexInsideAction(l *lexer) stateFn {
+	// Either number, quoted string, or identifier.
+	// Spaces separate arguments; runs of spaces turn into itemSpace.
+	// Pipe symbols separate and are emitted.
+	delim, _ := l.atRightDelim()
+	if delim {
+		if l.parenDepth == 0 {
+			return lexRightDelim
+		}
+		return l.errorf("unclosed left paren")
+	}
+	switch r := l.next(); {
+	case r == eof:
+		return l.errorf("unclosed action")
+	case isSpace(r):
+		l.backup() // Put space back in case we have " -}}".
+		return lexSpace
+	case r == '=':
+		l.emit(itemAssign)
+	case r == ':':
+		if l.next() != '=' {
+			return l.errorf("expected :=")
+		}
+		l.emit(itemDeclare)
+	case r == '|':
+		l.emit(itemPipe)
+	case r == '"':
+		return lexQuote
+	case r == '`':
+		return lexRawQuote
+	case r == '$':
+		return lexVariable
+	case r == '\'':
+		return lexChar
+	case r == '.':
+		// special look-ahead for ".field" so we don't break l.backup().
+		if l.pos < Pos(len(l.input)) {
+			r := l.input[l.pos]
+			if r < '0' || '9' < r {
+				return lexField
+			}
+		}
+		fallthrough // '.' can start a number.
+	case r == '+' || r == '-' || ('0' <= r && r <= '9'):
+		l.backup()
+		return lexNumber
+	case isAlphaNumeric(r):
+		l.backup()
+		return lexIdentifier
+	case r == '(':
+		l.emit(itemLeftParen)
+		l.parenDepth++
+	case r == ')':
+		l.emit(itemRightParen)
+		l.parenDepth--
+		if l.parenDepth < 0 {
+			return l.errorf("unexpected right paren %#U", r)
+		}
+	case r <= unicode.MaxASCII && unicode.IsPrint(r):
+		l.emit(itemChar)
+	default:
+		return l.errorf("unrecognized character in action: %#U", r)
+	}
+	return lexInsideAction
+}
+
+// lexSpace scans a run of space characters.
+// We have not consumed the first space, which is known to be present.
+// Take care if there is a trim-marked right delimiter, which starts with a space.
+func lexSpace(l *lexer) stateFn {
+	var r rune
+	var numSpaces int
+	for {
+		r = l.peek()
+		if !isSpace(r) {
+			break
+		}
+		l.next()
+		numSpaces++
+	}
+	// Be careful about a trim-marked closing delimiter, which has a minus
+	// after a space. We know there is a space, so check for the '-' that might follow.
+	if hasRightTrimMarker(l.input[l.pos-1:]) && strings.HasPrefix(l.input[l.pos-1+trimMarkerLen:], l.rightDelim) {
+		l.backup() // Before the space.
+		if numSpaces == 1 {
+			return lexRightDelim // On the delim, so go right to that.
+		}
+	}
+	l.emit(itemSpace)
+	return lexInsideAction
+}
+
+// lexIdentifier scans an alphanumeric.
+func lexIdentifier(l *lexer) stateFn {
+Loop:
+	for {
+		switch r := l.next(); {
+		case isAlphaNumeric(r):
+			// absorb.
+		default:
+			l.backup()
+			word := l.input[l.start:l.pos]
+			if !l.atTerminator() {
+				return l.errorf("bad character %#U", r)
+			}
+			switch {
+			case key[word] > itemKeyword:
+				item := key[word]
+				if item == itemBreak && !l.breakOK || item == itemContinue && !l.continueOK {
+					l.emit(itemIdentifier)
+				} else {
+					l.emit(item)
+				}
+			case word[0] == '.':
+				l.emit(itemField)
+			case word == "true", word == "false":
+				l.emit(itemBool)
+			default:
+				l.emit(itemIdentifier)
+			}
+			break Loop
+		}
+	}
+	return lexInsideAction
+}
+
+// lexField scans a field: .Alphanumeric.
+// The . has been scanned.
+func lexField(l *lexer) stateFn {
+	return lexFieldOrVariable(l, itemField)
+}
+
+// lexVariable scans a Variable: $Alphanumeric.
+// The $ has been scanned.
+func lexVariable(l *lexer) stateFn {
+	if l.atTerminator() { // Nothing interesting follows -> "$".
+		l.emit(itemVariable)
+		return lexInsideAction
+	}
+	return lexFieldOrVariable(l, itemVariable)
+}
+
+// lexVariable scans a field or variable: [.$]Alphanumeric.
+// The . or $ has been scanned.
+func lexFieldOrVariable(l *lexer, typ itemType) stateFn {
+	if l.atTerminator() { // Nothing interesting follows -> "." or "$".
+		if typ == itemVariable {
+			l.emit(itemVariable)
+		} else {
+			l.emit(itemDot)
+		}
+		return lexInsideAction
+	}
+	var r rune
+	for {
+		r = l.next()
+		if !isAlphaNumeric(r) {
+			l.backup()
+			break
+		}
+	}
+	if !l.atTerminator() {
+		return l.errorf("bad character %#U", r)
+	}
+	l.emit(typ)
+	return lexInsideAction
+}
+
+// atTerminator reports whether the input is at valid termination character to
+// appear after an identifier. Breaks .X.Y into two pieces. Also catches cases
+// like "$x+2" not being acceptable without a space, in case we decide one
+// day to implement arithmetic.
+func (l *lexer) atTerminator() bool {
+	r := l.peek()
+	if isSpace(r) {
+		return true
+	}
+	switch r {
+	case eof, '.', ',', '|', ':', ')', '(':
+		return true
+	}
+	return strings.HasPrefix(l.input[l.pos:], l.rightDelim)
+}
+
+// lexChar scans a character constant. The initial quote is already
+// scanned. Syntax checking is done by the parser.
+func lexChar(l *lexer) stateFn {
+Loop:
+	for {
+		switch l.next() {
+		case '\\':
+			if r := l.next(); r != eof && r != '\n' {
+				break
+			}
+			fallthrough
+		case eof, '\n':
+			return l.errorf("unterminated character constant")
+		case '\'':
+			break Loop
+		}
+	}
+	l.emit(itemCharConstant)
+	return lexInsideAction
+}
+
+// lexNumber scans a number: decimal, octal, hex, float, or imaginary. This
+// isn't a perfect number scanner - for instance it accepts "." and "0x0.2"
+// and "089" - but when it's wrong the input is invalid and the parser (via
+// strconv) will notice.
+func lexNumber(l *lexer) stateFn {
+	if !l.scanNumber() {
+		return l.errorf("bad number syntax: %q", l.input[l.start:l.pos])
+	}
+	if sign := l.peek(); sign == '+' || sign == '-' {
+		// Complex: 1+2i. No spaces, must end in 'i'.
+		if !l.scanNumber() || l.input[l.pos-1] != 'i' {
+			return l.errorf("bad number syntax: %q", l.input[l.start:l.pos])
+		}
+		l.emit(itemComplex)
+	} else {
+		l.emit(itemNumber)
+	}
+	return lexInsideAction
+}
+
+func (l *lexer) scanNumber() bool {
+	// Optional leading sign.
+	l.accept("+-")
+	// Is it hex?
+	digits := "0123456789_"
+	if l.accept("0") {
+		// Note: Leading 0 does not mean octal in floats.
+		if l.accept("xX") {
+			digits = "0123456789abcdefABCDEF_"
+		} else if l.accept("oO") {
+			digits = "01234567_"
+		} else if l.accept("bB") {
+			digits = "01_"
+		}
+	}
+	l.acceptRun(digits)
+	if l.accept(".") {
+		l.acceptRun(digits)
+	}
+	if len(digits) == 10+1 && l.accept("eE") {
+		l.accept("+-")
+		l.acceptRun("0123456789_")
+	}
+	if len(digits) == 16+6+1 && l.accept("pP") {
+		l.accept("+-")
+		l.acceptRun("0123456789_")
+	}
+	// Is it imaginary?
+	l.accept("i")
+	// Next thing mustn't be alphanumeric.
+	if isAlphaNumeric(l.peek()) {
+		l.next()
+		return false
+	}
+	return true
+}
+
+// lexQuote scans a quoted string.
+func lexQuote(l *lexer) stateFn {
+Loop:
+	for {
+		switch l.next() {
+		case '\\':
+			if r := l.next(); r != eof && r != '\n' {
+				break
+			}
+			fallthrough
+		case eof, '\n':
+			return l.errorf("unterminated quoted string")
+		case '"':
+			break Loop
+		}
+	}
+	l.emit(itemString)
+	return lexInsideAction
+}
+
+// lexRawQuote scans a raw quoted string.
+func lexRawQuote(l *lexer) stateFn {
+Loop:
+	for {
+		switch l.next() {
+		case eof:
+			return l.errorf("unterminated raw quoted string")
+		case '`':
+			break Loop
+		}
+	}
+	l.emit(itemRawString)
+	return lexInsideAction
+}
+
+// isSpace reports whether r is a space character.
+func isSpace(r rune) bool {
+	return r == ' ' || r == '\t' || r == '\r' || r == '\n'
+}
+
+// isAlphaNumeric reports whether r is an alphabetic, digit, or underscore.
+func isAlphaNumeric(r rune) bool {
+	return r == '_' || unicode.IsLetter(r) || unicode.IsDigit(r)
+}
+
+func hasLeftTrimMarker(s string) bool {
+	return len(s) >= 2 && s[0] == trimMarker && isSpace(rune(s[1]))
+}
+
+func hasRightTrimMarker(s string) bool {
+	return len(s) >= 2 && isSpace(rune(s[0])) && s[1] == trimMarker
+}
diff --git a/contrib/go/_std_1.18/src/text/template/parse/node.go b/contrib/go/_std_1.19/src/text/template/parse/node.go
index 47268225c8..47268225c8 100644
--- a/contrib/go/_std_1.18/src/text/template/parse/node.go
+++ b/contrib/go/_std_1.19/src/text/template/parse/node.go
diff --git a/contrib/go/_std_1.19/src/text/template/parse/parse.go b/contrib/go/_std_1.19/src/text/template/parse/parse.go
new file mode 100644
index 0000000000..00c258ad5d
--- /dev/null
+++ b/contrib/go/_std_1.19/src/text/template/parse/parse.go
@@ -0,0 +1,826 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package parse builds parse trees for templates as defined by text/template
+// and html/template. Clients should use those packages to construct templates
+// rather than this one, which provides shared internal data structures not
+// intended for general use.
+package parse
+
+import (
+	"bytes"
+	"fmt"
+	"runtime"
+	"strconv"
+	"strings"
+)
+
+// Tree is the representation of a single parsed template.
+type Tree struct {
+	Name      string    // name of the template represented by the tree.
+	ParseName string    // name of the top-level template during parsing, for error messages.
+	Root      *ListNode // top-level root of the tree.
+	Mode      Mode      // parsing mode.
+	text      string    // text parsed to create the template (or its parent)
+	// Parsing only; cleared after parse.
+	funcs      []map[string]any
+	lex        *lexer
+	token      [3]item // three-token lookahead for parser.
+	peekCount  int
+	vars       []string // variables defined at the moment.
+	treeSet    map[string]*Tree
+	actionLine int // line of left delim starting action
+	rangeDepth int
+}
+
+// A mode value is a set of flags (or 0). Modes control parser behavior.
+type Mode uint
+
+const (
+	ParseComments Mode = 1 << iota // parse comments and add them to AST
+	SkipFuncCheck                  // do not check that functions are defined
+)
+
+// Copy returns a copy of the Tree. Any parsing state is discarded.
+func (t *Tree) Copy() *Tree {
+	if t == nil {
+		return nil
+	}
+	return &Tree{
+		Name:      t.Name,
+		ParseName: t.ParseName,
+		Root:      t.Root.CopyList(),
+		text:      t.text,
+	}
+}
+
+// Parse returns a map from template name to parse.Tree, created by parsing the
+// templates described in the argument string. The top-level template will be
+// given the specified name. If an error is encountered, parsing stops and an
+// empty map is returned with the error.
+func Parse(name, text, leftDelim, rightDelim string, funcs ...map[string]any) (map[string]*Tree, error) {
+	treeSet := make(map[string]*Tree)
+	t := New(name)
+	t.text = text
+	_, err := t.Parse(text, leftDelim, rightDelim, treeSet, funcs...)
+	return treeSet, err
+}
+
+// next returns the next token.
+func (t *Tree) next() item {
+	if t.peekCount > 0 {
+		t.peekCount--
+	} else {
+		t.token[0] = t.lex.nextItem()
+	}
+	return t.token[t.peekCount]
+}
+
+// backup backs the input stream up one token.
+func (t *Tree) backup() {
+	t.peekCount++
+}
+
+// backup2 backs the input stream up two tokens.
+// The zeroth token is already there.
+func (t *Tree) backup2(t1 item) {
+	t.token[1] = t1
+	t.peekCount = 2
+}
+
+// backup3 backs the input stream up three tokens
+// The zeroth token is already there.
+func (t *Tree) backup3(t2, t1 item) { // Reverse order: we're pushing back.
+	t.token[1] = t1
+	t.token[2] = t2
+	t.peekCount = 3
+}
+
+// peek returns but does not consume the next token.
+func (t *Tree) peek() item {
+	if t.peekCount > 0 {
+		return t.token[t.peekCount-1]
+	}
+	t.peekCount = 1
+	t.token[0] = t.lex.nextItem()
+	return t.token[0]
+}
+
+// nextNonSpace returns the next non-space token.
+func (t *Tree) nextNonSpace() (token item) {
+	for {
+		token = t.next()
+		if token.typ != itemSpace {
+			break
+		}
+	}
+	return token
+}
+
+// peekNonSpace returns but does not consume the next non-space token.
+func (t *Tree) peekNonSpace() item {
+	token := t.nextNonSpace()
+	t.backup()
+	return token
+}
+
+// Parsing.
+
+// New allocates a new parse tree with the given name.
+func New(name string, funcs ...map[string]any) *Tree {
+	return &Tree{
+		Name:  name,
+		funcs: funcs,
+	}
+}
+
+// ErrorContext returns a textual representation of the location of the node in the input text.
+// The receiver is only used when the node does not have a pointer to the tree inside,
+// which can occur in old code.
+func (t *Tree) ErrorContext(n Node) (location, context string) {
+	pos := int(n.Position())
+	tree := n.tree()
+	if tree == nil {
+		tree = t
+	}
+	text := tree.text[:pos]
+	byteNum := strings.LastIndex(text, "\n")
+	if byteNum == -1 {
+		byteNum = pos // On first line.
+	} else {
+		byteNum++ // After the newline.
+		byteNum = pos - byteNum
+	}
+	lineNum := 1 + strings.Count(text, "\n")
+	context = n.String()
+	return fmt.Sprintf("%s:%d:%d", tree.ParseName, lineNum, byteNum), context
+}
+
+// errorf formats the error and terminates processing.
+func (t *Tree) errorf(format string, args ...any) {
+	t.Root = nil
+	format = fmt.Sprintf("template: %s:%d: %s", t.ParseName, t.token[0].line, format)
+	panic(fmt.Errorf(format, args...))
+}
+
+// error terminates processing.
+func (t *Tree) error(err error) {
+	t.errorf("%s", err)
+}
+
+// expect consumes the next token and guarantees it has the required type.
+func (t *Tree) expect(expected itemType, context string) item {
+	token := t.nextNonSpace()
+	if token.typ != expected {
+		t.unexpected(token, context)
+	}
+	return token
+}
+
+// expectOneOf consumes the next token and guarantees it has one of the required types.
+func (t *Tree) expectOneOf(expected1, expected2 itemType, context string) item {
+	token := t.nextNonSpace()
+	if token.typ != expected1 && token.typ != expected2 {
+		t.unexpected(token, context)
+	}
+	return token
+}
+
+// unexpected complains about the token and terminates processing.
+func (t *Tree) unexpected(token item, context string) {
+	if token.typ == itemError {
+		extra := ""
+		if t.actionLine != 0 && t.actionLine != token.line {
+			extra = fmt.Sprintf(" in action started at %s:%d", t.ParseName, t.actionLine)
+			if strings.HasSuffix(token.val, " action") {
+				extra = extra[len(" in action"):] // avoid "action in action"
+			}
+		}
+		t.errorf("%s%s", token, extra)
+	}
+	t.errorf("unexpected %s in %s", token, context)
+}
+
+// recover is the handler that turns panics into returns from the top level of Parse.
+func (t *Tree) recover(errp *error) {
+	e := recover()
+	if e != nil {
+		if _, ok := e.(runtime.Error); ok {
+			panic(e)
+		}
+		if t != nil {
+			t.lex.drain()
+			t.stopParse()
+		}
+		*errp = e.(error)
+	}
+}
+
+// startParse initializes the parser, using the lexer.
+func (t *Tree) startParse(funcs []map[string]any, lex *lexer, treeSet map[string]*Tree) {
+	t.Root = nil
+	t.lex = lex
+	t.vars = []string{"$"}
+	t.funcs = funcs
+	t.treeSet = treeSet
+}
+
+// stopParse terminates parsing.
+func (t *Tree) stopParse() {
+	t.lex = nil
+	t.vars = nil
+	t.funcs = nil
+	t.treeSet = nil
+}
+
+// Parse parses the template definition string to construct a representation of
+// the template for execution. If either action delimiter string is empty, the
+// default ("{{" or "}}") is used. Embedded template definitions are added to
+// the treeSet map.
+func (t *Tree) Parse(text, leftDelim, rightDelim string, treeSet map[string]*Tree, funcs ...map[string]any) (tree *Tree, err error) {
+	defer t.recover(&err)
+	t.ParseName = t.Name
+	emitComment := t.Mode&ParseComments != 0
+	breakOK := !t.hasFunction("break")
+	continueOK := !t.hasFunction("continue")
+	lexer := lex(t.Name, text, leftDelim, rightDelim, emitComment, breakOK, continueOK)
+	t.startParse(funcs, lexer, treeSet)
+	t.text = text
+	t.parse()
+	t.add()
+	t.stopParse()
+	return t, nil
+}
+
+// add adds tree to t.treeSet.
+func (t *Tree) add() {
+	tree := t.treeSet[t.Name]
+	if tree == nil || IsEmptyTree(tree.Root) {
+		t.treeSet[t.Name] = t
+		return
+	}
+	if !IsEmptyTree(t.Root) {
+		t.errorf("template: multiple definition of template %q", t.Name)
+	}
+}
+
+// IsEmptyTree reports whether this tree (node) is empty of everything but space or comments.
+func IsEmptyTree(n Node) bool {
+	switch n := n.(type) {
+	case nil:
+		return true
+	case *ActionNode:
+	case *CommentNode:
+		return true
+	case *IfNode:
+	case *ListNode:
+		for _, node := range n.Nodes {
+			if !IsEmptyTree(node) {
+				return false
+			}
+		}
+		return true
+	case *RangeNode:
+	case *TemplateNode:
+	case *TextNode:
+		return len(bytes.TrimSpace(n.Text)) == 0
+	case *WithNode:
+	default:
+		panic("unknown node: " + n.String())
+	}
+	return false
+}
+
+// parse is the top-level parser for a template, essentially the same
+// as itemList except it also parses {{define}} actions.
+// It runs to EOF.
+func (t *Tree) parse() {
+	t.Root = t.newList(t.peek().pos)
+	for t.peek().typ != itemEOF {
+		if t.peek().typ == itemLeftDelim {
+			delim := t.next()
+			if t.nextNonSpace().typ == itemDefine {
+				newT := New("definition") // name will be updated once we know it.
+				newT.text = t.text
+				newT.Mode = t.Mode
+				newT.ParseName = t.ParseName
+				newT.startParse(t.funcs, t.lex, t.treeSet)
+				newT.parseDefinition()
+				continue
+			}
+			t.backup2(delim)
+		}
+		switch n := t.textOrAction(); n.Type() {
+		case nodeEnd, nodeElse:
+			t.errorf("unexpected %s", n)
+		default:
+			t.Root.append(n)
+		}
+	}
+}
+
+// parseDefinition parses a {{define}} ...  {{end}} template definition and
+// installs the definition in t.treeSet. The "define" keyword has already
+// been scanned.
+func (t *Tree) parseDefinition() {
+	const context = "define clause"
+	name := t.expectOneOf(itemString, itemRawString, context)
+	var err error
+	t.Name, err = strconv.Unquote(name.val)
+	if err != nil {
+		t.error(err)
+	}
+	t.expect(itemRightDelim, context)
+	var end Node
+	t.Root, end = t.itemList()
+	if end.Type() != nodeEnd {
+		t.errorf("unexpected %s in %s", end, context)
+	}
+	t.add()
+	t.stopParse()
+}
+
+// itemList:
+//
+//	textOrAction*
+//
+// Terminates at {{end}} or {{else}}, returned separately.
+func (t *Tree) itemList() (list *ListNode, next Node) {
+	list = t.newList(t.peekNonSpace().pos)
+	for t.peekNonSpace().typ != itemEOF {
+		n := t.textOrAction()
+		switch n.Type() {
+		case nodeEnd, nodeElse:
+			return list, n
+		}
+		list.append(n)
+	}
+	t.errorf("unexpected EOF")
+	return
+}
+
+// textOrAction:
+//
+//	text | comment | action
+func (t *Tree) textOrAction() Node {
+	switch token := t.nextNonSpace(); token.typ {
+	case itemText:
+		return t.newText(token.pos, token.val)
+	case itemLeftDelim:
+		t.actionLine = token.line
+		defer t.clearActionLine()
+		return t.action()
+	case itemComment:
+		return t.newComment(token.pos, token.val)
+	default:
+		t.unexpected(token, "input")
+	}
+	return nil
+}
+
+func (t *Tree) clearActionLine() {
+	t.actionLine = 0
+}
+
+// Action:
+//
+//	control
+//	command ("|" command)*
+//
+// Left delim is past. Now get actions.
+// First word could be a keyword such as range.
+func (t *Tree) action() (n Node) {
+	switch token := t.nextNonSpace(); token.typ {
+	case itemBlock:
+		return t.blockControl()
+	case itemBreak:
+		return t.breakControl(token.pos, token.line)
+	case itemContinue:
+		return t.continueControl(token.pos, token.line)
+	case itemElse:
+		return t.elseControl()
+	case itemEnd:
+		return t.endControl()
+	case itemIf:
+		return t.ifControl()
+	case itemRange:
+		return t.rangeControl()
+	case itemTemplate:
+		return t.templateControl()
+	case itemWith:
+		return t.withControl()
+	}
+	t.backup()
+	token := t.peek()
+	// Do not pop variables; they persist until "end".
+	return t.newAction(token.pos, token.line, t.pipeline("command", itemRightDelim))
+}
+
+// Break:
+//
+//	{{break}}
+//
+// Break keyword is past.
+func (t *Tree) breakControl(pos Pos, line int) Node {
+	if token := t.nextNonSpace(); token.typ != itemRightDelim {
+		t.unexpected(token, "{{break}}")
+	}
+	if t.rangeDepth == 0 {
+		t.errorf("{{break}} outside {{range}}")
+	}
+	return t.newBreak(pos, line)
+}
+
+// Continue:
+//
+//	{{continue}}
+//
+// Continue keyword is past.
+func (t *Tree) continueControl(pos Pos, line int) Node {
+	if token := t.nextNonSpace(); token.typ != itemRightDelim {
+		t.unexpected(token, "{{continue}}")
+	}
+	if t.rangeDepth == 0 {
+		t.errorf("{{continue}} outside {{range}}")
+	}
+	return t.newContinue(pos, line)
+}
+
+// Pipeline:
+//
+//	declarations? command ('|' command)*
+func (t *Tree) pipeline(context string, end itemType) (pipe *PipeNode) {
+	token := t.peekNonSpace()
+	pipe = t.newPipeline(token.pos, token.line, nil)
+	// Are there declarations or assignments?
+decls:
+	if v := t.peekNonSpace(); v.typ == itemVariable {
+		t.next()
+		// Since space is a token, we need 3-token look-ahead here in the worst case:
+		// in "$x foo" we need to read "foo" (as opposed to ":=") to know that $x is an
+		// argument variable rather than a declaration. So remember the token
+		// adjacent to the variable so we can push it back if necessary.
+		tokenAfterVariable := t.peek()
+		next := t.peekNonSpace()
+		switch {
+		case next.typ == itemAssign, next.typ == itemDeclare:
+			pipe.IsAssign = next.typ == itemAssign
+			t.nextNonSpace()
+			pipe.Decl = append(pipe.Decl, t.newVariable(v.pos, v.val))
+			t.vars = append(t.vars, v.val)
+		case next.typ == itemChar && next.val == ",":
+			t.nextNonSpace()
+			pipe.Decl = append(pipe.Decl, t.newVariable(v.pos, v.val))
+			t.vars = append(t.vars, v.val)
+			if context == "range" && len(pipe.Decl) < 2 {
+				switch t.peekNonSpace().typ {
+				case itemVariable, itemRightDelim, itemRightParen:
+					// second initialized variable in a range pipeline
+					goto decls
+				default:
+					t.errorf("range can only initialize variables")
+				}
+			}
+			t.errorf("too many declarations in %s", context)
+		case tokenAfterVariable.typ == itemSpace:
+			t.backup3(v, tokenAfterVariable)
+		default:
+			t.backup2(v)
+		}
+	}
+	for {
+		switch token := t.nextNonSpace(); token.typ {
+		case end:
+			// At this point, the pipeline is complete
+			t.checkPipeline(pipe, context)
+			return
+		case itemBool, itemCharConstant, itemComplex, itemDot, itemField, itemIdentifier,
+			itemNumber, itemNil, itemRawString, itemString, itemVariable, itemLeftParen:
+			t.backup()
+			pipe.append(t.command())
+		default:
+			t.unexpected(token, context)
+		}
+	}
+}
+
+func (t *Tree) checkPipeline(pipe *PipeNode, context string) {
+	// Reject empty pipelines
+	if len(pipe.Cmds) == 0 {
+		t.errorf("missing value for %s", context)
+	}
+	// Only the first command of a pipeline can start with a non executable operand
+	for i, c := range pipe.Cmds[1:] {
+		switch c.Args[0].Type() {
+		case NodeBool, NodeDot, NodeNil, NodeNumber, NodeString:
+			// With A|B|C, pipeline stage 2 is B
+			t.errorf("non executable command in pipeline stage %d", i+2)
+		}
+	}
+}
+
+func (t *Tree) parseControl(allowElseIf bool, context string) (pos Pos, line int, pipe *PipeNode, list, elseList *ListNode) {
+	defer t.popVars(len(t.vars))
+	pipe = t.pipeline(context, itemRightDelim)
+	if context == "range" {
+		t.rangeDepth++
+	}
+	var next Node
+	list, next = t.itemList()
+	if context == "range" {
+		t.rangeDepth--
+	}
+	switch next.Type() {
+	case nodeEnd: //done
+	case nodeElse:
+		if allowElseIf {
+			// Special case for "else if". If the "else" is followed immediately by an "if",
+			// the elseControl will have left the "if" token pending. Treat
+			//	{{if a}}_{{else if b}}_{{end}}
+			// as
+			//	{{if a}}_{{else}}{{if b}}_{{end}}{{end}}.
+			// To do this, parse the if as usual and stop at it {{end}}; the subsequent{{end}}
+			// is assumed. This technique works even for long if-else-if chains.
+			// TODO: Should we allow else-if in with and range?
+			if t.peek().typ == itemIf {
+				t.next() // Consume the "if" token.
+				elseList = t.newList(next.Position())
+				elseList.append(t.ifControl())
+				// Do not consume the next item - only one {{end}} required.
+				break
+			}
+		}
+		elseList, next = t.itemList()
+		if next.Type() != nodeEnd {
+			t.errorf("expected end; found %s", next)
+		}
+	}
+	return pipe.Position(), pipe.Line, pipe, list, elseList
+}
+
+// If:
+//
+//	{{if pipeline}} itemList {{end}}
+//	{{if pipeline}} itemList {{else}} itemList {{end}}
+//
+// If keyword is past.
+func (t *Tree) ifControl() Node {
+	return t.newIf(t.parseControl(true, "if"))
+}
+
+// Range:
+//
+//	{{range pipeline}} itemList {{end}}
+//	{{range pipeline}} itemList {{else}} itemList {{end}}
+//
+// Range keyword is past.
+func (t *Tree) rangeControl() Node {
+	r := t.newRange(t.parseControl(false, "range"))
+	return r
+}
+
+// With:
+//
+//	{{with pipeline}} itemList {{end}}
+//	{{with pipeline}} itemList {{else}} itemList {{end}}
+//
+// If keyword is past.
+func (t *Tree) withControl() Node {
+	return t.newWith(t.parseControl(false, "with"))
+}
+
+// End:
+//
+//	{{end}}
+//
+// End keyword is past.
+func (t *Tree) endControl() Node {
+	return t.newEnd(t.expect(itemRightDelim, "end").pos)
+}
+
+// Else:
+//
+//	{{else}}
+//
+// Else keyword is past.
+func (t *Tree) elseControl() Node {
+	// Special case for "else if".
+	peek := t.peekNonSpace()
+	if peek.typ == itemIf {
+		// We see "{{else if ... " but in effect rewrite it to {{else}}{{if ... ".
+		return t.newElse(peek.pos, peek.line)
+	}
+	token := t.expect(itemRightDelim, "else")
+	return t.newElse(token.pos, token.line)
+}
+
+// Block:
+//
+//	{{block stringValue pipeline}}
+//
+// Block keyword is past.
+// The name must be something that can evaluate to a string.
+// The pipeline is mandatory.
+func (t *Tree) blockControl() Node {
+	const context = "block clause"
+
+	token := t.nextNonSpace()
+	name := t.parseTemplateName(token, context)
+	pipe := t.pipeline(context, itemRightDelim)
+
+	block := New(name) // name will be updated once we know it.
+	block.text = t.text
+	block.Mode = t.Mode
+	block.ParseName = t.ParseName
+	block.startParse(t.funcs, t.lex, t.treeSet)
+	var end Node
+	block.Root, end = block.itemList()
+	if end.Type() != nodeEnd {
+		t.errorf("unexpected %s in %s", end, context)
+	}
+	block.add()
+	block.stopParse()
+
+	return t.newTemplate(token.pos, token.line, name, pipe)
+}
+
+// Template:
+//
+//	{{template stringValue pipeline}}
+//
+// Template keyword is past. The name must be something that can evaluate
+// to a string.
+func (t *Tree) templateControl() Node {
+	const context = "template clause"
+	token := t.nextNonSpace()
+	name := t.parseTemplateName(token, context)
+	var pipe *PipeNode
+	if t.nextNonSpace().typ != itemRightDelim {
+		t.backup()
+		// Do not pop variables; they persist until "end".
+		pipe = t.pipeline(context, itemRightDelim)
+	}
+	return t.newTemplate(token.pos, token.line, name, pipe)
+}
+
+func (t *Tree) parseTemplateName(token item, context string) (name string) {
+	switch token.typ {
+	case itemString, itemRawString:
+		s, err := strconv.Unquote(token.val)
+		if err != nil {
+			t.error(err)
+		}
+		name = s
+	default:
+		t.unexpected(token, context)
+	}
+	return
+}
+
+// command:
+//
+//	operand (space operand)*
+//
+// space-separated arguments up to a pipeline character or right delimiter.
+// we consume the pipe character but leave the right delim to terminate the action.
+func (t *Tree) command() *CommandNode {
+	cmd := t.newCommand(t.peekNonSpace().pos)
+	for {
+		t.peekNonSpace() // skip leading spaces.
+		operand := t.operand()
+		if operand != nil {
+			cmd.append(operand)
+		}
+		switch token := t.next(); token.typ {
+		case itemSpace:
+			continue
+		case itemRightDelim, itemRightParen:
+			t.backup()
+		case itemPipe:
+			// nothing here; break loop below
+		default:
+			t.unexpected(token, "operand")
+		}
+		break
+	}
+	if len(cmd.Args) == 0 {
+		t.errorf("empty command")
+	}
+	return cmd
+}
+
+// operand:
+//
+//	term .Field*
+//
+// An operand is a space-separated component of a command,
+// a term possibly followed by field accesses.
+// A nil return means the next item is not an operand.
+func (t *Tree) operand() Node {
+	node := t.term()
+	if node == nil {
+		return nil
+	}
+	if t.peek().typ == itemField {
+		chain := t.newChain(t.peek().pos, node)
+		for t.peek().typ == itemField {
+			chain.Add(t.next().val)
+		}
+		// Compatibility with original API: If the term is of type NodeField
+		// or NodeVariable, just put more fields on the original.
+		// Otherwise, keep the Chain node.
+		// Obvious parsing errors involving literal values are detected here.
+		// More complex error cases will have to be handled at execution time.
+		switch node.Type() {
+		case NodeField:
+			node = t.newField(chain.Position(), chain.String())
+		case NodeVariable:
+			node = t.newVariable(chain.Position(), chain.String())
+		case NodeBool, NodeString, NodeNumber, NodeNil, NodeDot:
+			t.errorf("unexpected . after term %q", node.String())
+		default:
+			node = chain
+		}
+	}
+	return node
+}
+
+// term:
+//
+//	literal (number, string, nil, boolean)
+//	function (identifier)
+//	.
+//	.Field
+//	$
+//	'(' pipeline ')'
+//
+// A term is a simple "expression".
+// A nil return means the next item is not a term.
+func (t *Tree) term() Node {
+	switch token := t.nextNonSpace(); token.typ {
+	case itemIdentifier:
+		checkFunc := t.Mode&SkipFuncCheck == 0
+		if checkFunc && !t.hasFunction(token.val) {
+			t.errorf("function %q not defined", token.val)
+		}
+		return NewIdentifier(token.val).SetTree(t).SetPos(token.pos)
+	case itemDot:
+		return t.newDot(token.pos)
+	case itemNil:
+		return t.newNil(token.pos)
+	case itemVariable:
+		return t.useVar(token.pos, token.val)
+	case itemField:
+		return t.newField(token.pos, token.val)
+	case itemBool:
+		return t.newBool(token.pos, token.val == "true")
+	case itemCharConstant, itemComplex, itemNumber:
+		number, err := t.newNumber(token.pos, token.val, token.typ)
+		if err != nil {
+			t.error(err)
+		}
+		return number
+	case itemLeftParen:
+		return t.pipeline("parenthesized pipeline", itemRightParen)
+	case itemString, itemRawString:
+		s, err := strconv.Unquote(token.val)
+		if err != nil {
+			t.error(err)
+		}
+		return t.newString(token.pos, token.val, s)
+	}
+	t.backup()
+	return nil
+}
+
+// hasFunction reports if a function name exists in the Tree's maps.
+func (t *Tree) hasFunction(name string) bool {
+	for _, funcMap := range t.funcs {
+		if funcMap == nil {
+			continue
+		}
+		if funcMap[name] != nil {
+			return true
+		}
+	}
+	return false
+}
+
+// popVars trims the variable list to the specified length
+func (t *Tree) popVars(n int) {
+	t.vars = t.vars[:n]
+}
+
+// useVar returns a node for a variable reference. It errors if the
+// variable is not defined.
+func (t *Tree) useVar(pos Pos, name string) Node {
+	v := t.newVariable(pos, name)
+	for _, varName := range t.vars {
+		if varName == v.Ident[0] {
+			return v
+		}
+	}
+	t.errorf("undefined variable %q", v.Ident[0])
+	return nil
+}
diff --git a/contrib/go/_std_1.18/src/text/template/template.go b/contrib/go/_std_1.19/src/text/template/template.go
index 776be9cd07..776be9cd07 100644
--- a/contrib/go/_std_1.18/src/text/template/template.go
+++ b/contrib/go/_std_1.19/src/text/template/template.go
diff --git a/contrib/go/_std_1.19/src/time/format.go b/contrib/go/_std_1.19/src/time/format.go
new file mode 100644
index 0000000000..8431ff89b4
--- /dev/null
+++ b/contrib/go/_std_1.19/src/time/format.go
@@ -0,0 +1,1619 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package time
+
+import "errors"
+
+// These are predefined layouts for use in Time.Format and time.Parse.
+// The reference time used in these layouts is the specific time stamp:
+//
+//	01/02 03:04:05PM '06 -0700
+//
+// (January 2, 15:04:05, 2006, in time zone seven hours west of GMT).
+// That value is recorded as the constant named Layout, listed below. As a Unix
+// time, this is 1136239445. Since MST is GMT-0700, the reference would be
+// printed by the Unix date command as:
+//
+//	Mon Jan 2 15:04:05 MST 2006
+//
+// It is a regrettable historic error that the date uses the American convention
+// of putting the numerical month before the day.
+//
+// The example for Time.Format demonstrates the working of the layout string
+// in detail and is a good reference.
+//
+// Note that the RFC822, RFC850, and RFC1123 formats should be applied
+// only to local times. Applying them to UTC times will use "UTC" as the
+// time zone abbreviation, while strictly speaking those RFCs require the
+// use of "GMT" in that case.
+// In general RFC1123Z should be used instead of RFC1123 for servers
+// that insist on that format, and RFC3339 should be preferred for new protocols.
+// RFC3339, RFC822, RFC822Z, RFC1123, and RFC1123Z are useful for formatting;
+// when used with time.Parse they do not accept all the time formats
+// permitted by the RFCs and they do accept time formats not formally defined.
+// The RFC3339Nano format removes trailing zeros from the seconds field
+// and thus may not sort correctly once formatted.
+//
+// Most programs can use one of the defined constants as the layout passed to
+// Format or Parse. The rest of this comment can be ignored unless you are
+// creating a custom layout string.
+//
+// To define your own format, write down what the reference time would look like
+// formatted your way; see the values of constants like ANSIC, StampMicro or
+// Kitchen for examples. The model is to demonstrate what the reference time
+// looks like so that the Format and Parse methods can apply the same
+// transformation to a general time value.
+//
+// Here is a summary of the components of a layout string. Each element shows by
+// example the formatting of an element of the reference time. Only these values
+// are recognized. Text in the layout string that is not recognized as part of
+// the reference time is echoed verbatim during Format and expected to appear
+// verbatim in the input to Parse.
+//
+//	Year: "2006" "06"
+//	Month: "Jan" "January" "01" "1"
+//	Day of the week: "Mon" "Monday"
+//	Day of the month: "2" "_2" "02"
+//	Day of the year: "__2" "002"
+//	Hour: "15" "3" "03" (PM or AM)
+//	Minute: "4" "04"
+//	Second: "5" "05"
+//	AM/PM mark: "PM"
+//
+// Numeric time zone offsets format as follows:
+//
+//	"-0700"     ±hhmm
+//	"-07:00"    ±hh:mm
+//	"-07"       ±hh
+//	"-070000"   ±hhmmss
+//	"-07:00:00" ±hh:mm:ss
+//
+// Replacing the sign in the format with a Z triggers
+// the ISO 8601 behavior of printing Z instead of an
+// offset for the UTC zone. Thus:
+//
+//	"Z0700"      Z or ±hhmm
+//	"Z07:00"     Z or ±hh:mm
+//	"Z07"        Z or ±hh
+//	"Z070000"    Z or ±hhmmss
+//	"Z07:00:00"  Z or ±hh:mm:ss
+//
+// Within the format string, the underscores in "_2" and "__2" represent spaces
+// that may be replaced by digits if the following number has multiple digits,
+// for compatibility with fixed-width Unix time formats. A leading zero represents
+// a zero-padded value.
+//
+// The formats __2 and 002 are space-padded and zero-padded
+// three-character day of year; there is no unpadded day of year format.
+//
+// A comma or decimal point followed by one or more zeros represents
+// a fractional second, printed to the given number of decimal places.
+// A comma or decimal point followed by one or more nines represents
+// a fractional second, printed to the given number of decimal places, with
+// trailing zeros removed.
+// For example "15:04:05,000" or "15:04:05.000" formats or parses with
+// millisecond precision.
+//
+// Some valid layouts are invalid time values for time.Parse, due to formats
+// such as _ for space padding and Z for zone information.
+const (
+	Layout      = "01/02 03:04:05PM '06 -0700" // The reference time, in numerical order.
+	ANSIC       = "Mon Jan _2 15:04:05 2006"
+	UnixDate    = "Mon Jan _2 15:04:05 MST 2006"
+	RubyDate    = "Mon Jan 02 15:04:05 -0700 2006"
+	RFC822      = "02 Jan 06 15:04 MST"
+	RFC822Z     = "02 Jan 06 15:04 -0700" // RFC822 with numeric zone
+	RFC850      = "Monday, 02-Jan-06 15:04:05 MST"
+	RFC1123     = "Mon, 02 Jan 2006 15:04:05 MST"
+	RFC1123Z    = "Mon, 02 Jan 2006 15:04:05 -0700" // RFC1123 with numeric zone
+	RFC3339     = "2006-01-02T15:04:05Z07:00"
+	RFC3339Nano = "2006-01-02T15:04:05.999999999Z07:00"
+	Kitchen     = "3:04PM"
+	// Handy time stamps.
+	Stamp      = "Jan _2 15:04:05"
+	StampMilli = "Jan _2 15:04:05.000"
+	StampMicro = "Jan _2 15:04:05.000000"
+	StampNano  = "Jan _2 15:04:05.000000000"
+)
+
+const (
+	_                        = iota
+	stdLongMonth             = iota + stdNeedDate  // "January"
+	stdMonth                                       // "Jan"
+	stdNumMonth                                    // "1"
+	stdZeroMonth                                   // "01"
+	stdLongWeekDay                                 // "Monday"
+	stdWeekDay                                     // "Mon"
+	stdDay                                         // "2"
+	stdUnderDay                                    // "_2"
+	stdZeroDay                                     // "02"
+	stdUnderYearDay                                // "__2"
+	stdZeroYearDay                                 // "002"
+	stdHour                  = iota + stdNeedClock // "15"
+	stdHour12                                      // "3"
+	stdZeroHour12                                  // "03"
+	stdMinute                                      // "4"
+	stdZeroMinute                                  // "04"
+	stdSecond                                      // "5"
+	stdZeroSecond                                  // "05"
+	stdLongYear              = iota + stdNeedDate  // "2006"
+	stdYear                                        // "06"
+	stdPM                    = iota + stdNeedClock // "PM"
+	stdpm                                          // "pm"
+	stdTZ                    = iota                // "MST"
+	stdISO8601TZ                                   // "Z0700"  // prints Z for UTC
+	stdISO8601SecondsTZ                            // "Z070000"
+	stdISO8601ShortTZ                              // "Z07"
+	stdISO8601ColonTZ                              // "Z07:00" // prints Z for UTC
+	stdISO8601ColonSecondsTZ                       // "Z07:00:00"
+	stdNumTZ                                       // "-0700"  // always numeric
+	stdNumSecondsTz                                // "-070000"
+	stdNumShortTZ                                  // "-07"    // always numeric
+	stdNumColonTZ                                  // "-07:00" // always numeric
+	stdNumColonSecondsTZ                           // "-07:00:00"
+	stdFracSecond0                                 // ".0", ".00", ... , trailing zeros included
+	stdFracSecond9                                 // ".9", ".99", ..., trailing zeros omitted
+
+	stdNeedDate       = 1 << 8             // need month, day, year
+	stdNeedClock      = 2 << 8             // need hour, minute, second
+	stdArgShift       = 16                 // extra argument in high bits, above low stdArgShift
+	stdSeparatorShift = 28                 // extra argument in high 4 bits for fractional second separators
+	stdMask           = 1<<stdArgShift - 1 // mask out argument
+)
+
+// std0x records the std values for "01", "02", ..., "06".
+var std0x = [...]int{stdZeroMonth, stdZeroDay, stdZeroHour12, stdZeroMinute, stdZeroSecond, stdYear}
+
+// startsWithLowerCase reports whether the string has a lower-case letter at the beginning.
+// Its purpose is to prevent matching strings like "Month" when looking for "Mon".
+func startsWithLowerCase(str string) bool {
+	if len(str) == 0 {
+		return false
+	}
+	c := str[0]
+	return 'a' <= c && c <= 'z'
+}
+
+// nextStdChunk finds the first occurrence of a std string in
+// layout and returns the text before, the std string, and the text after.
+func nextStdChunk(layout string) (prefix string, std int, suffix string) {
+	for i := 0; i < len(layout); i++ {
+		switch c := int(layout[i]); c {
+		case 'J': // January, Jan
+			if len(layout) >= i+3 && layout[i:i+3] == "Jan" {
+				if len(layout) >= i+7 && layout[i:i+7] == "January" {
+					return layout[0:i], stdLongMonth, layout[i+7:]
+				}
+				if !startsWithLowerCase(layout[i+3:]) {
+					return layout[0:i], stdMonth, layout[i+3:]
+				}
+			}
+
+		case 'M': // Monday, Mon, MST
+			if len(layout) >= i+3 {
+				if layout[i:i+3] == "Mon" {
+					if len(layout) >= i+6 && layout[i:i+6] == "Monday" {
+						return layout[0:i], stdLongWeekDay, layout[i+6:]
+					}
+					if !startsWithLowerCase(layout[i+3:]) {
+						return layout[0:i], stdWeekDay, layout[i+3:]
+					}
+				}
+				if layout[i:i+3] == "MST" {
+					return layout[0:i], stdTZ, layout[i+3:]
+				}
+			}
+
+		case '0': // 01, 02, 03, 04, 05, 06, 002
+			if len(layout) >= i+2 && '1' <= layout[i+1] && layout[i+1] <= '6' {
+				return layout[0:i], std0x[layout[i+1]-'1'], layout[i+2:]
+			}
+			if len(layout) >= i+3 && layout[i+1] == '0' && layout[i+2] == '2' {
+				return layout[0:i], stdZeroYearDay, layout[i+3:]
+			}
+
+		case '1': // 15, 1
+			if len(layout) >= i+2 && layout[i+1] == '5' {
+				return layout[0:i], stdHour, layout[i+2:]
+			}
+			return layout[0:i], stdNumMonth, layout[i+1:]
+
+		case '2': // 2006, 2
+			if len(layout) >= i+4 && layout[i:i+4] == "2006" {
+				return layout[0:i], stdLongYear, layout[i+4:]
+			}
+			return layout[0:i], stdDay, layout[i+1:]
+
+		case '_': // _2, _2006, __2
+			if len(layout) >= i+2 && layout[i+1] == '2' {
+				//_2006 is really a literal _, followed by stdLongYear
+				if len(layout) >= i+5 && layout[i+1:i+5] == "2006" {
+					return layout[0 : i+1], stdLongYear, layout[i+5:]
+				}
+				return layout[0:i], stdUnderDay, layout[i+2:]
+			}
+			if len(layout) >= i+3 && layout[i+1] == '_' && layout[i+2] == '2' {
+				return layout[0:i], stdUnderYearDay, layout[i+3:]
+			}
+
+		case '3':
+			return layout[0:i], stdHour12, layout[i+1:]
+
+		case '4':
+			return layout[0:i], stdMinute, layout[i+1:]
+
+		case '5':
+			return layout[0:i], stdSecond, layout[i+1:]
+
+		case 'P': // PM
+			if len(layout) >= i+2 && layout[i+1] == 'M' {
+				return layout[0:i], stdPM, layout[i+2:]
+			}
+
+		case 'p': // pm
+			if len(layout) >= i+2 && layout[i+1] == 'm' {
+				return layout[0:i], stdpm, layout[i+2:]
+			}
+
+		case '-': // -070000, -07:00:00, -0700, -07:00, -07
+			if len(layout) >= i+7 && layout[i:i+7] == "-070000" {
+				return layout[0:i], stdNumSecondsTz, layout[i+7:]
+			}
+			if len(layout) >= i+9 && layout[i:i+9] == "-07:00:00" {
+				return layout[0:i], stdNumColonSecondsTZ, layout[i+9:]
+			}
+			if len(layout) >= i+5 && layout[i:i+5] == "-0700" {
+				return layout[0:i], stdNumTZ, layout[i+5:]
+			}
+			if len(layout) >= i+6 && layout[i:i+6] == "-07:00" {
+				return layout[0:i], stdNumColonTZ, layout[i+6:]
+			}
+			if len(layout) >= i+3 && layout[i:i+3] == "-07" {
+				return layout[0:i], stdNumShortTZ, layout[i+3:]
+			}
+
+		case 'Z': // Z070000, Z07:00:00, Z0700, Z07:00,
+			if len(layout) >= i+7 && layout[i:i+7] == "Z070000" {
+				return layout[0:i], stdISO8601SecondsTZ, layout[i+7:]
+			}
+			if len(layout) >= i+9 && layout[i:i+9] == "Z07:00:00" {
+				return layout[0:i], stdISO8601ColonSecondsTZ, layout[i+9:]
+			}
+			if len(layout) >= i+5 && layout[i:i+5] == "Z0700" {
+				return layout[0:i], stdISO8601TZ, layout[i+5:]
+			}
+			if len(layout) >= i+6 && layout[i:i+6] == "Z07:00" {
+				return layout[0:i], stdISO8601ColonTZ, layout[i+6:]
+			}
+			if len(layout) >= i+3 && layout[i:i+3] == "Z07" {
+				return layout[0:i], stdISO8601ShortTZ, layout[i+3:]
+			}
+
+		case '.', ',': // ,000, or .000, or ,999, or .999 - repeated digits for fractional seconds.
+			if i+1 < len(layout) && (layout[i+1] == '0' || layout[i+1] == '9') {
+				ch := layout[i+1]
+				j := i + 1
+				for j < len(layout) && layout[j] == ch {
+					j++
+				}
+				// String of digits must end here - only fractional second is all digits.
+				if !isDigit(layout, j) {
+					code := stdFracSecond0
+					if layout[i+1] == '9' {
+						code = stdFracSecond9
+					}
+					std := stdFracSecond(code, j-(i+1), c)
+					return layout[0:i], std, layout[j:]
+				}
+			}
+		}
+	}
+	return layout, 0, ""
+}
+
+var longDayNames = []string{
+	"Sunday",
+	"Monday",
+	"Tuesday",
+	"Wednesday",
+	"Thursday",
+	"Friday",
+	"Saturday",
+}
+
+var shortDayNames = []string{
+	"Sun",
+	"Mon",
+	"Tue",
+	"Wed",
+	"Thu",
+	"Fri",
+	"Sat",
+}
+
+var shortMonthNames = []string{
+	"Jan",
+	"Feb",
+	"Mar",
+	"Apr",
+	"May",
+	"Jun",
+	"Jul",
+	"Aug",
+	"Sep",
+	"Oct",
+	"Nov",
+	"Dec",
+}
+
+var longMonthNames = []string{
+	"January",
+	"February",
+	"March",
+	"April",
+	"May",
+	"June",
+	"July",
+	"August",
+	"September",
+	"October",
+	"November",
+	"December",
+}
+
+// match reports whether s1 and s2 match ignoring case.
+// It is assumed s1 and s2 are the same length.
+func match(s1, s2 string) bool {
+	for i := 0; i < len(s1); i++ {
+		c1 := s1[i]
+		c2 := s2[i]
+		if c1 != c2 {
+			// Switch to lower-case; 'a'-'A' is known to be a single bit.
+			c1 |= 'a' - 'A'
+			c2 |= 'a' - 'A'
+			if c1 != c2 || c1 < 'a' || c1 > 'z' {
+				return false
+			}
+		}
+	}
+	return true
+}
+
+func lookup(tab []string, val string) (int, string, error) {
+	for i, v := range tab {
+		if len(val) >= len(v) && match(val[0:len(v)], v) {
+			return i, val[len(v):], nil
+		}
+	}
+	return -1, val, errBad
+}
+
+// appendInt appends the decimal form of x to b and returns the result.
+// If the decimal form (excluding sign) is shorter than width, the result is padded with leading 0's.
+// Duplicates functionality in strconv, but avoids dependency.
+func appendInt(b []byte, x int, width int) []byte {
+	u := uint(x)
+	if x < 0 {
+		b = append(b, '-')
+		u = uint(-x)
+	}
+
+	// Assemble decimal in reverse order.
+	var buf [20]byte
+	i := len(buf)
+	for u >= 10 {
+		i--
+		q := u / 10
+		buf[i] = byte('0' + u - q*10)
+		u = q
+	}
+	i--
+	buf[i] = byte('0' + u)
+
+	// Add 0-padding.
+	for w := len(buf) - i; w < width; w++ {
+		b = append(b, '0')
+	}
+
+	return append(b, buf[i:]...)
+}
+
+// Never printed, just needs to be non-nil for return by atoi.
+var atoiError = errors.New("time: invalid number")
+
+// Duplicates functionality in strconv, but avoids dependency.
+func atoi(s string) (x int, err error) {
+	neg := false
+	if s != "" && (s[0] == '-' || s[0] == '+') {
+		neg = s[0] == '-'
+		s = s[1:]
+	}
+	q, rem, err := leadingInt(s)
+	x = int(q)
+	if err != nil || rem != "" {
+		return 0, atoiError
+	}
+	if neg {
+		x = -x
+	}
+	return x, nil
+}
+
+// The "std" value passed to formatNano contains two packed fields: the number of
+// digits after the decimal and the separator character (period or comma).
+// These functions pack and unpack that variable.
+func stdFracSecond(code, n, c int) int {
+	// Use 0xfff to make the failure case even more absurd.
+	if c == '.' {
+		return code | ((n & 0xfff) << stdArgShift)
+	}
+	return code | ((n & 0xfff) << stdArgShift) | 1<<stdSeparatorShift
+}
+
+func digitsLen(std int) int {
+	return (std >> stdArgShift) & 0xfff
+}
+
+func separator(std int) byte {
+	if (std >> stdSeparatorShift) == 0 {
+		return '.'
+	}
+	return ','
+}
+
+// formatNano appends a fractional second, as nanoseconds, to b
+// and returns the result.
+func formatNano(b []byte, nanosec uint, std int) []byte {
+	var (
+		n         = digitsLen(std)
+		separator = separator(std)
+		trim      = std&stdMask == stdFracSecond9
+	)
+	u := nanosec
+	var buf [9]byte
+	for start := len(buf); start > 0; {
+		start--
+		buf[start] = byte(u%10 + '0')
+		u /= 10
+	}
+
+	if n > 9 {
+		n = 9
+	}
+	if trim {
+		for n > 0 && buf[n-1] == '0' {
+			n--
+		}
+		if n == 0 {
+			return b
+		}
+	}
+	b = append(b, separator)
+	return append(b, buf[:n]...)
+}
+
+// String returns the time formatted using the format string
+//
+//	"2006-01-02 15:04:05.999999999 -0700 MST"
+//
+// If the time has a monotonic clock reading, the returned string
+// includes a final field "m=±<value>", where value is the monotonic
+// clock reading formatted as a decimal number of seconds.
+//
+// The returned string is meant for debugging; for a stable serialized
+// representation, use t.MarshalText, t.MarshalBinary, or t.Format
+// with an explicit format string.
+func (t Time) String() string {
+	s := t.Format("2006-01-02 15:04:05.999999999 -0700 MST")
+
+	// Format monotonic clock reading as m=±ddd.nnnnnnnnn.
+	if t.wall&hasMonotonic != 0 {
+		m2 := uint64(t.ext)
+		sign := byte('+')
+		if t.ext < 0 {
+			sign = '-'
+			m2 = -m2
+		}
+		m1, m2 := m2/1e9, m2%1e9
+		m0, m1 := m1/1e9, m1%1e9
+		buf := make([]byte, 0, 24)
+		buf = append(buf, " m="...)
+		buf = append(buf, sign)
+		wid := 0
+		if m0 != 0 {
+			buf = appendInt(buf, int(m0), 0)
+			wid = 9
+		}
+		buf = appendInt(buf, int(m1), wid)
+		buf = append(buf, '.')
+		buf = appendInt(buf, int(m2), 9)
+		s += string(buf)
+	}
+	return s
+}
+
+// GoString implements fmt.GoStringer and formats t to be printed in Go source
+// code.
+func (t Time) GoString() string {
+	buf := make([]byte, 0, 70)
+	buf = append(buf, "time.Date("...)
+	buf = appendInt(buf, t.Year(), 0)
+	month := t.Month()
+	if January <= month && month <= December {
+		buf = append(buf, ", time."...)
+		buf = append(buf, t.Month().String()...)
+	} else {
+		// It's difficult to construct a time.Time with a date outside the
+		// standard range but we might as well try to handle the case.
+		buf = appendInt(buf, int(month), 0)
+	}
+	buf = append(buf, ", "...)
+	buf = appendInt(buf, t.Day(), 0)
+	buf = append(buf, ", "...)
+	buf = appendInt(buf, t.Hour(), 0)
+	buf = append(buf, ", "...)
+	buf = appendInt(buf, t.Minute(), 0)
+	buf = append(buf, ", "...)
+	buf = appendInt(buf, t.Second(), 0)
+	buf = append(buf, ", "...)
+	buf = appendInt(buf, t.Nanosecond(), 0)
+	buf = append(buf, ", "...)
+	switch loc := t.Location(); loc {
+	case UTC, nil:
+		buf = append(buf, "time.UTC"...)
+	case Local:
+		buf = append(buf, "time.Local"...)
+	default:
+		// there are several options for how we could display this, none of
+		// which are great:
+		//
+		// - use Location(loc.name), which is not technically valid syntax
+		// - use LoadLocation(loc.name), which will cause a syntax error when
+		// embedded and also would require us to escape the string without
+		// importing fmt or strconv
+		// - try to use FixedZone, which would also require escaping the name
+		// and would represent e.g. "America/Los_Angeles" daylight saving time
+		// shifts inaccurately
+		// - use the pointer format, which is no worse than you'd get with the
+		// old fmt.Sprintf("%#v", t) format.
+		//
+		// Of these, Location(loc.name) is the least disruptive. This is an edge
+		// case we hope not to hit too often.
+		buf = append(buf, `time.Location(`...)
+		buf = append(buf, []byte(quote(loc.name))...)
+		buf = append(buf, `)`...)
+	}
+	buf = append(buf, ')')
+	return string(buf)
+}
+
+// Format returns a textual representation of the time value formatted according
+// to the layout defined by the argument. See the documentation for the
+// constant called Layout to see how to represent the layout format.
+//
+// The executable example for Time.Format demonstrates the working
+// of the layout string in detail and is a good reference.
+func (t Time) Format(layout string) string {
+	const bufSize = 64
+	var b []byte
+	max := len(layout) + 10
+	if max < bufSize {
+		var buf [bufSize]byte
+		b = buf[:0]
+	} else {
+		b = make([]byte, 0, max)
+	}
+	b = t.AppendFormat(b, layout)
+	return string(b)
+}
+
+// AppendFormat is like Format but appends the textual
+// representation to b and returns the extended buffer.
+func (t Time) AppendFormat(b []byte, layout string) []byte {
+	var (
+		name, offset, abs = t.locabs()
+
+		year  int = -1
+		month Month
+		day   int
+		yday  int
+		hour  int = -1
+		min   int
+		sec   int
+	)
+	// Each iteration generates one std value.
+	for layout != "" {
+		prefix, std, suffix := nextStdChunk(layout)
+		if prefix != "" {
+			b = append(b, prefix...)
+		}
+		if std == 0 {
+			break
+		}
+		layout = suffix
+
+		// Compute year, month, day if needed.
+		if year < 0 && std&stdNeedDate != 0 {
+			year, month, day, yday = absDate(abs, true)
+			yday++
+		}
+
+		// Compute hour, minute, second if needed.
+		if hour < 0 && std&stdNeedClock != 0 {
+			hour, min, sec = absClock(abs)
+		}
+
+		switch std & stdMask {
+		case stdYear:
+			y := year
+			if y < 0 {
+				y = -y
+			}
+			b = appendInt(b, y%100, 2)
+		case stdLongYear:
+			b = appendInt(b, year, 4)
+		case stdMonth:
+			b = append(b, month.String()[:3]...)
+		case stdLongMonth:
+			m := month.String()
+			b = append(b, m...)
+		case stdNumMonth:
+			b = appendInt(b, int(month), 0)
+		case stdZeroMonth:
+			b = appendInt(b, int(month), 2)
+		case stdWeekDay:
+			b = append(b, absWeekday(abs).String()[:3]...)
+		case stdLongWeekDay:
+			s := absWeekday(abs).String()
+			b = append(b, s...)
+		case stdDay:
+			b = appendInt(b, day, 0)
+		case stdUnderDay:
+			if day < 10 {
+				b = append(b, ' ')
+			}
+			b = appendInt(b, day, 0)
+		case stdZeroDay:
+			b = appendInt(b, day, 2)
+		case stdUnderYearDay:
+			if yday < 100 {
+				b = append(b, ' ')
+				if yday < 10 {
+					b = append(b, ' ')
+				}
+			}
+			b = appendInt(b, yday, 0)
+		case stdZeroYearDay:
+			b = appendInt(b, yday, 3)
+		case stdHour:
+			b = appendInt(b, hour, 2)
+		case stdHour12:
+			// Noon is 12PM, midnight is 12AM.
+			hr := hour % 12
+			if hr == 0 {
+				hr = 12
+			}
+			b = appendInt(b, hr, 0)
+		case stdZeroHour12:
+			// Noon is 12PM, midnight is 12AM.
+			hr := hour % 12
+			if hr == 0 {
+				hr = 12
+			}
+			b = appendInt(b, hr, 2)
+		case stdMinute:
+			b = appendInt(b, min, 0)
+		case stdZeroMinute:
+			b = appendInt(b, min, 2)
+		case stdSecond:
+			b = appendInt(b, sec, 0)
+		case stdZeroSecond:
+			b = appendInt(b, sec, 2)
+		case stdPM:
+			if hour >= 12 {
+				b = append(b, "PM"...)
+			} else {
+				b = append(b, "AM"...)
+			}
+		case stdpm:
+			if hour >= 12 {
+				b = append(b, "pm"...)
+			} else {
+				b = append(b, "am"...)
+			}
+		case stdISO8601TZ, stdISO8601ColonTZ, stdISO8601SecondsTZ, stdISO8601ShortTZ, stdISO8601ColonSecondsTZ, stdNumTZ, stdNumColonTZ, stdNumSecondsTz, stdNumShortTZ, stdNumColonSecondsTZ:
+			// Ugly special case. We cheat and take the "Z" variants
+			// to mean "the time zone as formatted for ISO 8601".
+			if offset == 0 && (std == stdISO8601TZ || std == stdISO8601ColonTZ || std == stdISO8601SecondsTZ || std == stdISO8601ShortTZ || std == stdISO8601ColonSecondsTZ) {
+				b = append(b, 'Z')
+				break
+			}
+			zone := offset / 60 // convert to minutes
+			absoffset := offset
+			if zone < 0 {
+				b = append(b, '-')
+				zone = -zone
+				absoffset = -absoffset
+			} else {
+				b = append(b, '+')
+			}
+			b = appendInt(b, zone/60, 2)
+			if std == stdISO8601ColonTZ || std == stdNumColonTZ || std == stdISO8601ColonSecondsTZ || std == stdNumColonSecondsTZ {
+				b = append(b, ':')
+			}
+			if std != stdNumShortTZ && std != stdISO8601ShortTZ {
+				b = appendInt(b, zone%60, 2)
+			}
+
+			// append seconds if appropriate
+			if std == stdISO8601SecondsTZ || std == stdNumSecondsTz || std == stdNumColonSecondsTZ || std == stdISO8601ColonSecondsTZ {
+				if std == stdNumColonSecondsTZ || std == stdISO8601ColonSecondsTZ {
+					b = append(b, ':')
+				}
+				b = appendInt(b, absoffset%60, 2)
+			}
+
+		case stdTZ:
+			if name != "" {
+				b = append(b, name...)
+				break
+			}
+			// No time zone known for this time, but we must print one.
+			// Use the -0700 format.
+			zone := offset / 60 // convert to minutes
+			if zone < 0 {
+				b = append(b, '-')
+				zone = -zone
+			} else {
+				b = append(b, '+')
+			}
+			b = appendInt(b, zone/60, 2)
+			b = appendInt(b, zone%60, 2)
+		case stdFracSecond0, stdFracSecond9:
+			b = formatNano(b, uint(t.Nanosecond()), std)
+		}
+	}
+	return b
+}
+
+var errBad = errors.New("bad value for field") // placeholder not passed to user
+
+// ParseError describes a problem parsing a time string.
+type ParseError struct {
+	Layout     string
+	Value      string
+	LayoutElem string
+	ValueElem  string
+	Message    string
+}
+
+// These are borrowed from unicode/utf8 and strconv and replicate behavior in
+// that package, since we can't take a dependency on either.
+const (
+	lowerhex  = "0123456789abcdef"
+	runeSelf  = 0x80
+	runeError = '\uFFFD'
+)
+
+func quote(s string) string {
+	buf := make([]byte, 1, len(s)+2) // slice will be at least len(s) + quotes
+	buf[0] = '"'
+	for i, c := range s {
+		if c >= runeSelf || c < ' ' {
+			// This means you are asking us to parse a time.Duration or
+			// time.Location with unprintable or non-ASCII characters in it.
+			// We don't expect to hit this case very often. We could try to
+			// reproduce strconv.Quote's behavior with full fidelity but
+			// given how rarely we expect to hit these edge cases, speed and
+			// conciseness are better.
+			var width int
+			if c == runeError {
+				width = 1
+				if i+2 < len(s) && s[i:i+3] == string(runeError) {
+					width = 3
+				}
+			} else {
+				width = len(string(c))
+			}
+			for j := 0; j < width; j++ {
+				buf = append(buf, `\x`...)
+				buf = append(buf, lowerhex[s[i+j]>>4])
+				buf = append(buf, lowerhex[s[i+j]&0xF])
+			}
+		} else {
+			if c == '"' || c == '\\' {
+				buf = append(buf, '\\')
+			}
+			buf = append(buf, string(c)...)
+		}
+	}
+	buf = append(buf, '"')
+	return string(buf)
+}
+
+// Error returns the string representation of a ParseError.
+func (e *ParseError) Error() string {
+	if e.Message == "" {
+		return "parsing time " +
+			quote(e.Value) + " as " +
+			quote(e.Layout) + ": cannot parse " +
+			quote(e.ValueElem) + " as " +
+			quote(e.LayoutElem)
+	}
+	return "parsing time " +
+		quote(e.Value) + e.Message
+}
+
+// isDigit reports whether s[i] is in range and is a decimal digit.
+func isDigit(s string, i int) bool {
+	if len(s) <= i {
+		return false
+	}
+	c := s[i]
+	return '0' <= c && c <= '9'
+}
+
+// getnum parses s[0:1] or s[0:2] (fixed forces s[0:2])
+// as a decimal integer and returns the integer and the
+// remainder of the string.
+func getnum(s string, fixed bool) (int, string, error) {
+	if !isDigit(s, 0) {
+		return 0, s, errBad
+	}
+	if !isDigit(s, 1) {
+		if fixed {
+			return 0, s, errBad
+		}
+		return int(s[0] - '0'), s[1:], nil
+	}
+	return int(s[0]-'0')*10 + int(s[1]-'0'), s[2:], nil
+}
+
+// getnum3 parses s[0:1], s[0:2], or s[0:3] (fixed forces s[0:3])
+// as a decimal integer and returns the integer and the remainder
+// of the string.
+func getnum3(s string, fixed bool) (int, string, error) {
+	var n, i int
+	for i = 0; i < 3 && isDigit(s, i); i++ {
+		n = n*10 + int(s[i]-'0')
+	}
+	if i == 0 || fixed && i != 3 {
+		return 0, s, errBad
+	}
+	return n, s[i:], nil
+}
+
+func cutspace(s string) string {
+	for len(s) > 0 && s[0] == ' ' {
+		s = s[1:]
+	}
+	return s
+}
+
+// skip removes the given prefix from value,
+// treating runs of space characters as equivalent.
+func skip(value, prefix string) (string, error) {
+	for len(prefix) > 0 {
+		if prefix[0] == ' ' {
+			if len(value) > 0 && value[0] != ' ' {
+				return value, errBad
+			}
+			prefix = cutspace(prefix)
+			value = cutspace(value)
+			continue
+		}
+		if len(value) == 0 || value[0] != prefix[0] {
+			return value, errBad
+		}
+		prefix = prefix[1:]
+		value = value[1:]
+	}
+	return value, nil
+}
+
+// Parse parses a formatted string and returns the time value it represents.
+// See the documentation for the constant called Layout to see how to
+// represent the format. The second argument must be parseable using
+// the format string (layout) provided as the first argument.
+//
+// The example for Time.Format demonstrates the working of the layout string
+// in detail and is a good reference.
+//
+// When parsing (only), the input may contain a fractional second
+// field immediately after the seconds field, even if the layout does not
+// signify its presence. In that case either a comma or a decimal point
+// followed by a maximal series of digits is parsed as a fractional second.
+// Fractional seconds are truncated to nanosecond precision.
+//
+// Elements omitted from the layout are assumed to be zero or, when
+// zero is impossible, one, so parsing "3:04pm" returns the time
+// corresponding to Jan 1, year 0, 15:04:00 UTC (note that because the year is
+// 0, this time is before the zero Time).
+// Years must be in the range 0000..9999. The day of the week is checked
+// for syntax but it is otherwise ignored.
+//
+// For layouts specifying the two-digit year 06, a value NN >= 69 will be treated
+// as 19NN and a value NN < 69 will be treated as 20NN.
+//
+// The remainder of this comment describes the handling of time zones.
+//
+// In the absence of a time zone indicator, Parse returns a time in UTC.
+//
+// When parsing a time with a zone offset like -0700, if the offset corresponds
+// to a time zone used by the current location (Local), then Parse uses that
+// location and zone in the returned time. Otherwise it records the time as
+// being in a fabricated location with time fixed at the given zone offset.
+//
+// When parsing a time with a zone abbreviation like MST, if the zone abbreviation
+// has a defined offset in the current location, then that offset is used.
+// The zone abbreviation "UTC" is recognized as UTC regardless of location.
+// If the zone abbreviation is unknown, Parse records the time as being
+// in a fabricated location with the given zone abbreviation and a zero offset.
+// This choice means that such a time can be parsed and reformatted with the
+// same layout losslessly, but the exact instant used in the representation will
+// differ by the actual zone offset. To avoid such problems, prefer time layouts
+// that use a numeric zone offset, or use ParseInLocation.
+func Parse(layout, value string) (Time, error) {
+	return parse(layout, value, UTC, Local)
+}
+
+// ParseInLocation is like Parse but differs in two important ways.
+// First, in the absence of time zone information, Parse interprets a time as UTC;
+// ParseInLocation interprets the time as in the given location.
+// Second, when given a zone offset or abbreviation, Parse tries to match it
+// against the Local location; ParseInLocation uses the given location.
+func ParseInLocation(layout, value string, loc *Location) (Time, error) {
+	return parse(layout, value, loc, loc)
+}
+
+func parse(layout, value string, defaultLocation, local *Location) (Time, error) {
+	alayout, avalue := layout, value
+	rangeErrString := "" // set if a value is out of range
+	amSet := false       // do we need to subtract 12 from the hour for midnight?
+	pmSet := false       // do we need to add 12 to the hour?
+
+	// Time being constructed.
+	var (
+		year       int
+		month      int = -1
+		day        int = -1
+		yday       int = -1
+		hour       int
+		min        int
+		sec        int
+		nsec       int
+		z          *Location
+		zoneOffset int = -1
+		zoneName   string
+	)
+
+	// Each iteration processes one std value.
+	for {
+		var err error
+		prefix, std, suffix := nextStdChunk(layout)
+		stdstr := layout[len(prefix) : len(layout)-len(suffix)]
+		value, err = skip(value, prefix)
+		if err != nil {
+			return Time{}, &ParseError{alayout, avalue, prefix, value, ""}
+		}
+		if std == 0 {
+			if len(value) != 0 {
+				return Time{}, &ParseError{alayout, avalue, "", value, ": extra text: " + quote(value)}
+			}
+			break
+		}
+		layout = suffix
+		var p string
+		switch std & stdMask {
+		case stdYear:
+			if len(value) < 2 {
+				err = errBad
+				break
+			}
+			hold := value
+			p, value = value[0:2], value[2:]
+			year, err = atoi(p)
+			if err != nil {
+				value = hold
+			} else if year >= 69 { // Unix time starts Dec 31 1969 in some time zones
+				year += 1900
+			} else {
+				year += 2000
+			}
+		case stdLongYear:
+			if len(value) < 4 || !isDigit(value, 0) {
+				err = errBad
+				break
+			}
+			p, value = value[0:4], value[4:]
+			year, err = atoi(p)
+		case stdMonth:
+			month, value, err = lookup(shortMonthNames, value)
+			month++
+		case stdLongMonth:
+			month, value, err = lookup(longMonthNames, value)
+			month++
+		case stdNumMonth, stdZeroMonth:
+			month, value, err = getnum(value, std == stdZeroMonth)
+			if err == nil && (month <= 0 || 12 < month) {
+				rangeErrString = "month"
+			}
+		case stdWeekDay:
+			// Ignore weekday except for error checking.
+			_, value, err = lookup(shortDayNames, value)
+		case stdLongWeekDay:
+			_, value, err = lookup(longDayNames, value)
+		case stdDay, stdUnderDay, stdZeroDay:
+			if std == stdUnderDay && len(value) > 0 && value[0] == ' ' {
+				value = value[1:]
+			}
+			day, value, err = getnum(value, std == stdZeroDay)
+			// Note that we allow any one- or two-digit day here.
+			// The month, day, year combination is validated after we've completed parsing.
+		case stdUnderYearDay, stdZeroYearDay:
+			for i := 0; i < 2; i++ {
+				if std == stdUnderYearDay && len(value) > 0 && value[0] == ' ' {
+					value = value[1:]
+				}
+			}
+			yday, value, err = getnum3(value, std == stdZeroYearDay)
+			// Note that we allow any one-, two-, or three-digit year-day here.
+			// The year-day, year combination is validated after we've completed parsing.
+		case stdHour:
+			hour, value, err = getnum(value, false)
+			if hour < 0 || 24 <= hour {
+				rangeErrString = "hour"
+			}
+		case stdHour12, stdZeroHour12:
+			hour, value, err = getnum(value, std == stdZeroHour12)
+			if hour < 0 || 12 < hour {
+				rangeErrString = "hour"
+			}
+		case stdMinute, stdZeroMinute:
+			min, value, err = getnum(value, std == stdZeroMinute)
+			if min < 0 || 60 <= min {
+				rangeErrString = "minute"
+			}
+		case stdSecond, stdZeroSecond:
+			sec, value, err = getnum(value, std == stdZeroSecond)
+			if sec < 0 || 60 <= sec {
+				rangeErrString = "second"
+				break
+			}
+			// Special case: do we have a fractional second but no
+			// fractional second in the format?
+			if len(value) >= 2 && commaOrPeriod(value[0]) && isDigit(value, 1) {
+				_, std, _ = nextStdChunk(layout)
+				std &= stdMask
+				if std == stdFracSecond0 || std == stdFracSecond9 {
+					// Fractional second in the layout; proceed normally
+					break
+				}
+				// No fractional second in the layout but we have one in the input.
+				n := 2
+				for ; n < len(value) && isDigit(value, n); n++ {
+				}
+				nsec, rangeErrString, err = parseNanoseconds(value, n)
+				value = value[n:]
+			}
+		case stdPM:
+			if len(value) < 2 {
+				err = errBad
+				break
+			}
+			p, value = value[0:2], value[2:]
+			switch p {
+			case "PM":
+				pmSet = true
+			case "AM":
+				amSet = true
+			default:
+				err = errBad
+			}
+		case stdpm:
+			if len(value) < 2 {
+				err = errBad
+				break
+			}
+			p, value = value[0:2], value[2:]
+			switch p {
+			case "pm":
+				pmSet = true
+			case "am":
+				amSet = true
+			default:
+				err = errBad
+			}
+		case stdISO8601TZ, stdISO8601ColonTZ, stdISO8601SecondsTZ, stdISO8601ShortTZ, stdISO8601ColonSecondsTZ, stdNumTZ, stdNumShortTZ, stdNumColonTZ, stdNumSecondsTz, stdNumColonSecondsTZ:
+			if (std == stdISO8601TZ || std == stdISO8601ShortTZ || std == stdISO8601ColonTZ) && len(value) >= 1 && value[0] == 'Z' {
+				value = value[1:]
+				z = UTC
+				break
+			}
+			var sign, hour, min, seconds string
+			if std == stdISO8601ColonTZ || std == stdNumColonTZ {
+				if len(value) < 6 {
+					err = errBad
+					break
+				}
+				if value[3] != ':' {
+					err = errBad
+					break
+				}
+				sign, hour, min, seconds, value = value[0:1], value[1:3], value[4:6], "00", value[6:]
+			} else if std == stdNumShortTZ || std == stdISO8601ShortTZ {
+				if len(value) < 3 {
+					err = errBad
+					break
+				}
+				sign, hour, min, seconds, value = value[0:1], value[1:3], "00", "00", value[3:]
+			} else if std == stdISO8601ColonSecondsTZ || std == stdNumColonSecondsTZ {
+				if len(value) < 9 {
+					err = errBad
+					break
+				}
+				if value[3] != ':' || value[6] != ':' {
+					err = errBad
+					break
+				}
+				sign, hour, min, seconds, value = value[0:1], value[1:3], value[4:6], value[7:9], value[9:]
+			} else if std == stdISO8601SecondsTZ || std == stdNumSecondsTz {
+				if len(value) < 7 {
+					err = errBad
+					break
+				}
+				sign, hour, min, seconds, value = value[0:1], value[1:3], value[3:5], value[5:7], value[7:]
+			} else {
+				if len(value) < 5 {
+					err = errBad
+					break
+				}
+				sign, hour, min, seconds, value = value[0:1], value[1:3], value[3:5], "00", value[5:]
+			}
+			var hr, mm, ss int
+			hr, err = atoi(hour)
+			if err == nil {
+				mm, err = atoi(min)
+			}
+			if err == nil {
+				ss, err = atoi(seconds)
+			}
+			zoneOffset = (hr*60+mm)*60 + ss // offset is in seconds
+			switch sign[0] {
+			case '+':
+			case '-':
+				zoneOffset = -zoneOffset
+			default:
+				err = errBad
+			}
+		case stdTZ:
+			// Does it look like a time zone?
+			if len(value) >= 3 && value[0:3] == "UTC" {
+				z = UTC
+				value = value[3:]
+				break
+			}
+			n, ok := parseTimeZone(value)
+			if !ok {
+				err = errBad
+				break
+			}
+			zoneName, value = value[:n], value[n:]
+
+		case stdFracSecond0:
+			// stdFracSecond0 requires the exact number of digits as specified in
+			// the layout.
+			ndigit := 1 + digitsLen(std)
+			if len(value) < ndigit {
+				err = errBad
+				break
+			}
+			nsec, rangeErrString, err = parseNanoseconds(value, ndigit)
+			value = value[ndigit:]
+
+		case stdFracSecond9:
+			if len(value) < 2 || !commaOrPeriod(value[0]) || value[1] < '0' || '9' < value[1] {
+				// Fractional second omitted.
+				break
+			}
+			// Take any number of digits, even more than asked for,
+			// because it is what the stdSecond case would do.
+			i := 0
+			for i < 9 && i+1 < len(value) && '0' <= value[i+1] && value[i+1] <= '9' {
+				i++
+			}
+			nsec, rangeErrString, err = parseNanoseconds(value, 1+i)
+			value = value[1+i:]
+		}
+		if rangeErrString != "" {
+			return Time{}, &ParseError{alayout, avalue, stdstr, value, ": " + rangeErrString + " out of range"}
+		}
+		if err != nil {
+			return Time{}, &ParseError{alayout, avalue, stdstr, value, ""}
+		}
+	}
+	if pmSet && hour < 12 {
+		hour += 12
+	} else if amSet && hour == 12 {
+		hour = 0
+	}
+
+	// Convert yday to day, month.
+	if yday >= 0 {
+		var d int
+		var m int
+		if isLeap(year) {
+			if yday == 31+29 {
+				m = int(February)
+				d = 29
+			} else if yday > 31+29 {
+				yday--
+			}
+		}
+		if yday < 1 || yday > 365 {
+			return Time{}, &ParseError{alayout, avalue, "", value, ": day-of-year out of range"}
+		}
+		if m == 0 {
+			m = (yday-1)/31 + 1
+			if int(daysBefore[m]) < yday {
+				m++
+			}
+			d = yday - int(daysBefore[m-1])
+		}
+		// If month, day already seen, yday's m, d must match.
+		// Otherwise, set them from m, d.
+		if month >= 0 && month != m {
+			return Time{}, &ParseError{alayout, avalue, "", value, ": day-of-year does not match month"}
+		}
+		month = m
+		if day >= 0 && day != d {
+			return Time{}, &ParseError{alayout, avalue, "", value, ": day-of-year does not match day"}
+		}
+		day = d
+	} else {
+		if month < 0 {
+			month = int(January)
+		}
+		if day < 0 {
+			day = 1
+		}
+	}
+
+	// Validate the day of the month.
+	if day < 1 || day > daysIn(Month(month), year) {
+		return Time{}, &ParseError{alayout, avalue, "", value, ": day out of range"}
+	}
+
+	if z != nil {
+		return Date(year, Month(month), day, hour, min, sec, nsec, z), nil
+	}
+
+	if zoneOffset != -1 {
+		t := Date(year, Month(month), day, hour, min, sec, nsec, UTC)
+		t.addSec(-int64(zoneOffset))
+
+		// Look for local zone with the given offset.
+		// If that zone was in effect at the given time, use it.
+		name, offset, _, _, _ := local.lookup(t.unixSec())
+		if offset == zoneOffset && (zoneName == "" || name == zoneName) {
+			t.setLoc(local)
+			return t, nil
+		}
+
+		// Otherwise create fake zone to record offset.
+		t.setLoc(FixedZone(zoneName, zoneOffset))
+		return t, nil
+	}
+
+	if zoneName != "" {
+		t := Date(year, Month(month), day, hour, min, sec, nsec, UTC)
+		// Look for local zone with the given offset.
+		// If that zone was in effect at the given time, use it.
+		offset, ok := local.lookupName(zoneName, t.unixSec())
+		if ok {
+			t.addSec(-int64(offset))
+			t.setLoc(local)
+			return t, nil
+		}
+
+		// Otherwise, create fake zone with unknown offset.
+		if len(zoneName) > 3 && zoneName[:3] == "GMT" {
+			offset, _ = atoi(zoneName[3:]) // Guaranteed OK by parseGMT.
+			offset *= 3600
+		}
+		t.setLoc(FixedZone(zoneName, offset))
+		return t, nil
+	}
+
+	// Otherwise, fall back to default.
+	return Date(year, Month(month), day, hour, min, sec, nsec, defaultLocation), nil
+}
+
+// parseTimeZone parses a time zone string and returns its length. Time zones
+// are human-generated and unpredictable. We can't do precise error checking.
+// On the other hand, for a correct parse there must be a time zone at the
+// beginning of the string, so it's almost always true that there's one
+// there. We look at the beginning of the string for a run of upper-case letters.
+// If there are more than 5, it's an error.
+// If there are 4 or 5 and the last is a T, it's a time zone.
+// If there are 3, it's a time zone.
+// Otherwise, other than special cases, it's not a time zone.
+// GMT is special because it can have an hour offset.
+func parseTimeZone(value string) (length int, ok bool) {
+	if len(value) < 3 {
+		return 0, false
+	}
+	// Special case 1: ChST and MeST are the only zones with a lower-case letter.
+	if len(value) >= 4 && (value[:4] == "ChST" || value[:4] == "MeST") {
+		return 4, true
+	}
+	// Special case 2: GMT may have an hour offset; treat it specially.
+	if value[:3] == "GMT" {
+		length = parseGMT(value)
+		return length, true
+	}
+	// Special Case 3: Some time zones are not named, but have +/-00 format
+	if value[0] == '+' || value[0] == '-' {
+		length = parseSignedOffset(value)
+		ok := length > 0 // parseSignedOffset returns 0 in case of bad input
+		return length, ok
+	}
+	// How many upper-case letters are there? Need at least three, at most five.
+	var nUpper int
+	for nUpper = 0; nUpper < 6; nUpper++ {
+		if nUpper >= len(value) {
+			break
+		}
+		if c := value[nUpper]; c < 'A' || 'Z' < c {
+			break
+		}
+	}
+	switch nUpper {
+	case 0, 1, 2, 6:
+		return 0, false
+	case 5: // Must end in T to match.
+		if value[4] == 'T' {
+			return 5, true
+		}
+	case 4:
+		// Must end in T, except one special case.
+		if value[3] == 'T' || value[:4] == "WITA" {
+			return 4, true
+		}
+	case 3:
+		return 3, true
+	}
+	return 0, false
+}
+
+// parseGMT parses a GMT time zone. The input string is known to start "GMT".
+// The function checks whether that is followed by a sign and a number in the
+// range -23 through +23 excluding zero.
+func parseGMT(value string) int {
+	value = value[3:]
+	if len(value) == 0 {
+		return 3
+	}
+
+	return 3 + parseSignedOffset(value)
+}
+
+// parseSignedOffset parses a signed timezone offset (e.g. "+03" or "-04").
+// The function checks for a signed number in the range -23 through +23 excluding zero.
+// Returns length of the found offset string or 0 otherwise
+func parseSignedOffset(value string) int {
+	sign := value[0]
+	if sign != '-' && sign != '+' {
+		return 0
+	}
+	x, rem, err := leadingInt(value[1:])
+
+	// fail if nothing consumed by leadingInt
+	if err != nil || value[1:] == rem {
+		return 0
+	}
+	if x > 23 {
+		return 0
+	}
+	return len(value) - len(rem)
+}
+
+func commaOrPeriod(b byte) bool {
+	return b == '.' || b == ','
+}
+
+func parseNanoseconds(value string, nbytes int) (ns int, rangeErrString string, err error) {
+	if !commaOrPeriod(value[0]) {
+		err = errBad
+		return
+	}
+	if nbytes > 10 {
+		value = value[:10]
+		nbytes = 10
+	}
+	if ns, err = atoi(value[1:nbytes]); err != nil {
+		return
+	}
+	if ns < 0 {
+		rangeErrString = "fractional second"
+		return
+	}
+	// We need nanoseconds, which means scaling by the number
+	// of missing digits in the format, maximum length 10.
+	scaleDigits := 10 - nbytes
+	for i := 0; i < scaleDigits; i++ {
+		ns *= 10
+	}
+	return
+}
+
+var errLeadingInt = errors.New("time: bad [0-9]*") // never printed
+
+// leadingInt consumes the leading [0-9]* from s.
+func leadingInt(s string) (x uint64, rem string, err error) {
+	i := 0
+	for ; i < len(s); i++ {
+		c := s[i]
+		if c < '0' || c > '9' {
+			break
+		}
+		if x > 1<<63/10 {
+			// overflow
+			return 0, "", errLeadingInt
+		}
+		x = x*10 + uint64(c) - '0'
+		if x > 1<<63 {
+			// overflow
+			return 0, "", errLeadingInt
+		}
+	}
+	return x, s[i:], nil
+}
+
+// leadingFraction consumes the leading [0-9]* from s.
+// It is used only for fractions, so does not return an error on overflow,
+// it just stops accumulating precision.
+func leadingFraction(s string) (x uint64, scale float64, rem string) {
+	i := 0
+	scale = 1
+	overflow := false
+	for ; i < len(s); i++ {
+		c := s[i]
+		if c < '0' || c > '9' {
+			break
+		}
+		if overflow {
+			continue
+		}
+		if x > (1<<63-1)/10 {
+			// It's possible for overflow to give a positive number, so take care.
+			overflow = true
+			continue
+		}
+		y := x*10 + uint64(c) - '0'
+		if y > 1<<63 {
+			overflow = true
+			continue
+		}
+		x = y
+		scale *= 10
+	}
+	return x, scale, s[i:]
+}
+
+var unitMap = map[string]uint64{
+	"ns": uint64(Nanosecond),
+	"us": uint64(Microsecond),
+	"µs": uint64(Microsecond), // U+00B5 = micro symbol
+	"μs": uint64(Microsecond), // U+03BC = Greek letter mu
+	"ms": uint64(Millisecond),
+	"s":  uint64(Second),
+	"m":  uint64(Minute),
+	"h":  uint64(Hour),
+}
+
+// ParseDuration parses a duration string.
+// A duration string is a possibly signed sequence of
+// decimal numbers, each with optional fraction and a unit suffix,
+// such as "300ms", "-1.5h" or "2h45m".
+// Valid time units are "ns", "us" (or "µs"), "ms", "s", "m", "h".
+func ParseDuration(s string) (Duration, error) {
+	// [-+]?([0-9]*(\.[0-9]*)?[a-z]+)+
+	orig := s
+	var d uint64
+	neg := false
+
+	// Consume [-+]?
+	if s != "" {
+		c := s[0]
+		if c == '-' || c == '+' {
+			neg = c == '-'
+			s = s[1:]
+		}
+	}
+	// Special case: if all that is left is "0", this is zero.
+	if s == "0" {
+		return 0, nil
+	}
+	if s == "" {
+		return 0, errors.New("time: invalid duration " + quote(orig))
+	}
+	for s != "" {
+		var (
+			v, f  uint64      // integers before, after decimal point
+			scale float64 = 1 // value = v + f/scale
+		)
+
+		var err error
+
+		// The next character must be [0-9.]
+		if !(s[0] == '.' || '0' <= s[0] && s[0] <= '9') {
+			return 0, errors.New("time: invalid duration " + quote(orig))
+		}
+		// Consume [0-9]*
+		pl := len(s)
+		v, s, err = leadingInt(s)
+		if err != nil {
+			return 0, errors.New("time: invalid duration " + quote(orig))
+		}
+		pre := pl != len(s) // whether we consumed anything before a period
+
+		// Consume (\.[0-9]*)?
+		post := false
+		if s != "" && s[0] == '.' {
+			s = s[1:]
+			pl := len(s)
+			f, scale, s = leadingFraction(s)
+			post = pl != len(s)
+		}
+		if !pre && !post {
+			// no digits (e.g. ".s" or "-.s")
+			return 0, errors.New("time: invalid duration " + quote(orig))
+		}
+
+		// Consume unit.
+		i := 0
+		for ; i < len(s); i++ {
+			c := s[i]
+			if c == '.' || '0' <= c && c <= '9' {
+				break
+			}
+		}
+		if i == 0 {
+			return 0, errors.New("time: missing unit in duration " + quote(orig))
+		}
+		u := s[:i]
+		s = s[i:]
+		unit, ok := unitMap[u]
+		if !ok {
+			return 0, errors.New("time: unknown unit " + quote(u) + " in duration " + quote(orig))
+		}
+		if v > 1<<63/unit {
+			// overflow
+			return 0, errors.New("time: invalid duration " + quote(orig))
+		}
+		v *= unit
+		if f > 0 {
+			// float64 is needed to be nanosecond accurate for fractions of hours.
+			// v >= 0 && (f*unit/scale) <= 3.6e+12 (ns/h, h is the largest unit)
+			v += uint64(float64(f) * (float64(unit) / scale))
+			if v > 1<<63 {
+				// overflow
+				return 0, errors.New("time: invalid duration " + quote(orig))
+			}
+		}
+		d += v
+		if d > 1<<63 {
+			return 0, errors.New("time: invalid duration " + quote(orig))
+		}
+	}
+	if neg {
+		return -Duration(d), nil
+	}
+	if d > 1<<63-1 {
+		return 0, errors.New("time: invalid duration " + quote(orig))
+	}
+	return Duration(d), nil
+}
diff --git a/contrib/go/_std_1.19/src/time/sleep.go b/contrib/go/_std_1.19/src/time/sleep.go
new file mode 100644
index 0000000000..cdab4782ad
--- /dev/null
+++ b/contrib/go/_std_1.19/src/time/sleep.go
@@ -0,0 +1,177 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package time
+
+// Sleep pauses the current goroutine for at least the duration d.
+// A negative or zero duration causes Sleep to return immediately.
+func Sleep(d Duration)
+
+// Interface to timers implemented in package runtime.
+// Must be in sync with ../runtime/time.go:/^type timer
+type runtimeTimer struct {
+	pp       uintptr
+	when     int64
+	period   int64
+	f        func(any, uintptr) // NOTE: must not be closure
+	arg      any
+	seq      uintptr
+	nextwhen int64
+	status   uint32
+}
+
+// when is a helper function for setting the 'when' field of a runtimeTimer.
+// It returns what the time will be, in nanoseconds, Duration d in the future.
+// If d is negative, it is ignored. If the returned value would be less than
+// zero because of an overflow, MaxInt64 is returned.
+func when(d Duration) int64 {
+	if d <= 0 {
+		return runtimeNano()
+	}
+	t := runtimeNano() + int64(d)
+	if t < 0 {
+		// N.B. runtimeNano() and d are always positive, so addition
+		// (including overflow) will never result in t == 0.
+		t = 1<<63 - 1 // math.MaxInt64
+	}
+	return t
+}
+
+func startTimer(*runtimeTimer)
+func stopTimer(*runtimeTimer) bool
+func resetTimer(*runtimeTimer, int64) bool
+func modTimer(t *runtimeTimer, when, period int64, f func(any, uintptr), arg any, seq uintptr)
+
+// The Timer type represents a single event.
+// When the Timer expires, the current time will be sent on C,
+// unless the Timer was created by AfterFunc.
+// A Timer must be created with NewTimer or AfterFunc.
+type Timer struct {
+	C <-chan Time
+	r runtimeTimer
+}
+
+// Stop prevents the Timer from firing.
+// It returns true if the call stops the timer, false if the timer has already
+// expired or been stopped.
+// Stop does not close the channel, to prevent a read from the channel succeeding
+// incorrectly.
+//
+// To ensure the channel is empty after a call to Stop, check the
+// return value and drain the channel.
+// For example, assuming the program has not received from t.C already:
+//
+//	if !t.Stop() {
+//		<-t.C
+//	}
+//
+// This cannot be done concurrent to other receives from the Timer's
+// channel or other calls to the Timer's Stop method.
+//
+// For a timer created with AfterFunc(d, f), if t.Stop returns false, then the timer
+// has already expired and the function f has been started in its own goroutine;
+// Stop does not wait for f to complete before returning.
+// If the caller needs to know whether f is completed, it must coordinate
+// with f explicitly.
+func (t *Timer) Stop() bool {
+	if t.r.f == nil {
+		panic("time: Stop called on uninitialized Timer")
+	}
+	return stopTimer(&t.r)
+}
+
+// NewTimer creates a new Timer that will send
+// the current time on its channel after at least duration d.
+func NewTimer(d Duration) *Timer {
+	c := make(chan Time, 1)
+	t := &Timer{
+		C: c,
+		r: runtimeTimer{
+			when: when(d),
+			f:    sendTime,
+			arg:  c,
+		},
+	}
+	startTimer(&t.r)
+	return t
+}
+
+// Reset changes the timer to expire after duration d.
+// It returns true if the timer had been active, false if the timer had
+// expired or been stopped.
+//
+// For a Timer created with NewTimer, Reset should be invoked only on
+// stopped or expired timers with drained channels.
+//
+// If a program has already received a value from t.C, the timer is known
+// to have expired and the channel drained, so t.Reset can be used directly.
+// If a program has not yet received a value from t.C, however,
+// the timer must be stopped and—if Stop reports that the timer expired
+// before being stopped—the channel explicitly drained:
+//
+//	if !t.Stop() {
+//		<-t.C
+//	}
+//	t.Reset(d)
+//
+// This should not be done concurrent to other receives from the Timer's
+// channel.
+//
+// Note that it is not possible to use Reset's return value correctly, as there
+// is a race condition between draining the channel and the new timer expiring.
+// Reset should always be invoked on stopped or expired channels, as described above.
+// The return value exists to preserve compatibility with existing programs.
+//
+// For a Timer created with AfterFunc(d, f), Reset either reschedules
+// when f will run, in which case Reset returns true, or schedules f
+// to run again, in which case it returns false.
+// When Reset returns false, Reset neither waits for the prior f to
+// complete before returning nor does it guarantee that the subsequent
+// goroutine running f does not run concurrently with the prior
+// one. If the caller needs to know whether the prior execution of
+// f is completed, it must coordinate with f explicitly.
+func (t *Timer) Reset(d Duration) bool {
+	if t.r.f == nil {
+		panic("time: Reset called on uninitialized Timer")
+	}
+	w := when(d)
+	return resetTimer(&t.r, w)
+}
+
+// sendTime does a non-blocking send of the current time on c.
+func sendTime(c any, seq uintptr) {
+	select {
+	case c.(chan Time) <- Now():
+	default:
+	}
+}
+
+// After waits for the duration to elapse and then sends the current time
+// on the returned channel.
+// It is equivalent to NewTimer(d).C.
+// The underlying Timer is not recovered by the garbage collector
+// until the timer fires. If efficiency is a concern, use NewTimer
+// instead and call Timer.Stop if the timer is no longer needed.
+func After(d Duration) <-chan Time {
+	return NewTimer(d).C
+}
+
+// AfterFunc waits for the duration to elapse and then calls f
+// in its own goroutine. It returns a Timer that can
+// be used to cancel the call using its Stop method.
+func AfterFunc(d Duration, f func()) *Timer {
+	t := &Timer{
+		r: runtimeTimer{
+			when: when(d),
+			f:    goFunc,
+			arg:  f,
+		},
+	}
+	startTimer(&t.r)
+	return t
+}
+
+func goFunc(arg any, seq uintptr) {
+	go arg.(func())()
+}
diff --git a/contrib/go/_std_1.19/src/time/sys_unix.go b/contrib/go/_std_1.19/src/time/sys_unix.go
new file mode 100644
index 0000000000..0f06aa6ccd
--- /dev/null
+++ b/contrib/go/_std_1.19/src/time/sys_unix.go
@@ -0,0 +1,54 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm)
+
+package time
+
+import (
+	"errors"
+	"syscall"
+)
+
+// for testing: whatever interrupts a sleep
+func interrupt() {
+	syscall.Kill(syscall.Getpid(), syscall.SIGCHLD)
+}
+
+func open(name string) (uintptr, error) {
+	fd, err := syscall.Open(name, syscall.O_RDONLY, 0)
+	if err != nil {
+		return 0, err
+	}
+	return uintptr(fd), nil
+}
+
+func read(fd uintptr, buf []byte) (int, error) {
+	return syscall.Read(int(fd), buf)
+}
+
+func closefd(fd uintptr) {
+	syscall.Close(int(fd))
+}
+
+func preadn(fd uintptr, buf []byte, off int) error {
+	whence := seekStart
+	if off < 0 {
+		whence = seekEnd
+	}
+	if _, err := syscall.Seek(int(fd), int64(off), whence); err != nil {
+		return err
+	}
+	for len(buf) > 0 {
+		m, err := syscall.Read(int(fd), buf)
+		if m <= 0 {
+			if err == nil {
+				return errors.New("short read")
+			}
+			return err
+		}
+		buf = buf[m:]
+	}
+	return nil
+}
diff --git a/contrib/go/_std_1.19/src/time/tick.go b/contrib/go/_std_1.19/src/time/tick.go
new file mode 100644
index 0000000000..dcfeca8783
--- /dev/null
+++ b/contrib/go/_std_1.19/src/time/tick.go
@@ -0,0 +1,73 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package time
+
+import "errors"
+
+// A Ticker holds a channel that delivers “ticks” of a clock
+// at intervals.
+type Ticker struct {
+	C <-chan Time // The channel on which the ticks are delivered.
+	r runtimeTimer
+}
+
+// NewTicker returns a new Ticker containing a channel that will send
+// the current time on the channel after each tick. The period of the
+// ticks is specified by the duration argument. The ticker will adjust
+// the time interval or drop ticks to make up for slow receivers.
+// The duration d must be greater than zero; if not, NewTicker will
+// panic. Stop the ticker to release associated resources.
+func NewTicker(d Duration) *Ticker {
+	if d <= 0 {
+		panic(errors.New("non-positive interval for NewTicker"))
+	}
+	// Give the channel a 1-element time buffer.
+	// If the client falls behind while reading, we drop ticks
+	// on the floor until the client catches up.
+	c := make(chan Time, 1)
+	t := &Ticker{
+		C: c,
+		r: runtimeTimer{
+			when:   when(d),
+			period: int64(d),
+			f:      sendTime,
+			arg:    c,
+		},
+	}
+	startTimer(&t.r)
+	return t
+}
+
+// Stop turns off a ticker. After Stop, no more ticks will be sent.
+// Stop does not close the channel, to prevent a concurrent goroutine
+// reading from the channel from seeing an erroneous "tick".
+func (t *Ticker) Stop() {
+	stopTimer(&t.r)
+}
+
+// Reset stops a ticker and resets its period to the specified duration.
+// The next tick will arrive after the new period elapses. The duration d
+// must be greater than zero; if not, Reset will panic.
+func (t *Ticker) Reset(d Duration) {
+	if d <= 0 {
+		panic("non-positive interval for Ticker.Reset")
+	}
+	if t.r.f == nil {
+		panic("time: Reset called on uninitialized Ticker")
+	}
+	modTimer(&t.r, when(d), int64(d), t.r.f, t.r.arg, t.r.seq)
+}
+
+// Tick is a convenience wrapper for NewTicker providing access to the ticking
+// channel only. While Tick is useful for clients that have no need to shut down
+// the Ticker, be aware that without a way to shut it down the underlying
+// Ticker cannot be recovered by the garbage collector; it "leaks".
+// Unlike NewTicker, Tick will return nil if d <= 0.
+func Tick(d Duration) <-chan Time {
+	if d <= 0 {
+		return nil
+	}
+	return NewTicker(d).C
+}
diff --git a/contrib/go/_std_1.19/src/time/time.go b/contrib/go/_std_1.19/src/time/time.go
new file mode 100644
index 0000000000..47b26e39a8
--- /dev/null
+++ b/contrib/go/_std_1.19/src/time/time.go
@@ -0,0 +1,1619 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package time provides functionality for measuring and displaying time.
+//
+// The calendrical calculations always assume a Gregorian calendar, with
+// no leap seconds.
+//
+// # Monotonic Clocks
+//
+// Operating systems provide both a “wall clock,” which is subject to
+// changes for clock synchronization, and a “monotonic clock,” which is
+// not. The general rule is that the wall clock is for telling time and
+// the monotonic clock is for measuring time. Rather than split the API,
+// in this package the Time returned by time.Now contains both a wall
+// clock reading and a monotonic clock reading; later time-telling
+// operations use the wall clock reading, but later time-measuring
+// operations, specifically comparisons and subtractions, use the
+// monotonic clock reading.
+//
+// For example, this code always computes a positive elapsed time of
+// approximately 20 milliseconds, even if the wall clock is changed during
+// the operation being timed:
+//
+//	start := time.Now()
+//	... operation that takes 20 milliseconds ...
+//	t := time.Now()
+//	elapsed := t.Sub(start)
+//
+// Other idioms, such as time.Since(start), time.Until(deadline), and
+// time.Now().Before(deadline), are similarly robust against wall clock
+// resets.
+//
+// The rest of this section gives the precise details of how operations
+// use monotonic clocks, but understanding those details is not required
+// to use this package.
+//
+// The Time returned by time.Now contains a monotonic clock reading.
+// If Time t has a monotonic clock reading, t.Add adds the same duration to
+// both the wall clock and monotonic clock readings to compute the result.
+// Because t.AddDate(y, m, d), t.Round(d), and t.Truncate(d) are wall time
+// computations, they always strip any monotonic clock reading from their results.
+// Because t.In, t.Local, and t.UTC are used for their effect on the interpretation
+// of the wall time, they also strip any monotonic clock reading from their results.
+// The canonical way to strip a monotonic clock reading is to use t = t.Round(0).
+//
+// If Times t and u both contain monotonic clock readings, the operations
+// t.After(u), t.Before(u), t.Equal(u), and t.Sub(u) are carried out
+// using the monotonic clock readings alone, ignoring the wall clock
+// readings. If either t or u contains no monotonic clock reading, these
+// operations fall back to using the wall clock readings.
+//
+// On some systems the monotonic clock will stop if the computer goes to sleep.
+// On such a system, t.Sub(u) may not accurately reflect the actual
+// time that passed between t and u.
+//
+// Because the monotonic clock reading has no meaning outside
+// the current process, the serialized forms generated by t.GobEncode,
+// t.MarshalBinary, t.MarshalJSON, and t.MarshalText omit the monotonic
+// clock reading, and t.Format provides no format for it. Similarly, the
+// constructors time.Date, time.Parse, time.ParseInLocation, and time.Unix,
+// as well as the unmarshalers t.GobDecode, t.UnmarshalBinary.
+// t.UnmarshalJSON, and t.UnmarshalText always create times with
+// no monotonic clock reading.
+//
+// The monotonic clock reading exists only in Time values. It is not
+// a part of Duration values or the Unix times returned by t.Unix and
+// friends.
+//
+// Note that the Go == operator compares not just the time instant but
+// also the Location and the monotonic clock reading. See the
+// documentation for the Time type for a discussion of equality
+// testing for Time values.
+//
+// For debugging, the result of t.String does include the monotonic
+// clock reading if present. If t != u because of different monotonic clock readings,
+// that difference will be visible when printing t.String() and u.String().
+package time
+
+import (
+	"errors"
+	_ "unsafe" // for go:linkname
+)
+
+// A Time represents an instant in time with nanosecond precision.
+//
+// Programs using times should typically store and pass them as values,
+// not pointers. That is, time variables and struct fields should be of
+// type time.Time, not *time.Time.
+//
+// A Time value can be used by multiple goroutines simultaneously except
+// that the methods GobDecode, UnmarshalBinary, UnmarshalJSON and
+// UnmarshalText are not concurrency-safe.
+//
+// Time instants can be compared using the Before, After, and Equal methods.
+// The Sub method subtracts two instants, producing a Duration.
+// The Add method adds a Time and a Duration, producing a Time.
+//
+// The zero value of type Time is January 1, year 1, 00:00:00.000000000 UTC.
+// As this time is unlikely to come up in practice, the IsZero method gives
+// a simple way of detecting a time that has not been initialized explicitly.
+//
+// Each Time has associated with it a Location, consulted when computing the
+// presentation form of the time, such as in the Format, Hour, and Year methods.
+// The methods Local, UTC, and In return a Time with a specific location.
+// Changing the location in this way changes only the presentation; it does not
+// change the instant in time being denoted and therefore does not affect the
+// computations described in earlier paragraphs.
+//
+// Representations of a Time value saved by the GobEncode, MarshalBinary,
+// MarshalJSON, and MarshalText methods store the Time.Location's offset, but not
+// the location name. They therefore lose information about Daylight Saving Time.
+//
+// In addition to the required “wall clock” reading, a Time may contain an optional
+// reading of the current process's monotonic clock, to provide additional precision
+// for comparison or subtraction.
+// See the “Monotonic Clocks” section in the package documentation for details.
+//
+// Note that the Go == operator compares not just the time instant but also the
+// Location and the monotonic clock reading. Therefore, Time values should not
+// be used as map or database keys without first guaranteeing that the
+// identical Location has been set for all values, which can be achieved
+// through use of the UTC or Local method, and that the monotonic clock reading
+// has been stripped by setting t = t.Round(0). In general, prefer t.Equal(u)
+// to t == u, since t.Equal uses the most accurate comparison available and
+// correctly handles the case when only one of its arguments has a monotonic
+// clock reading.
+type Time struct {
+	// wall and ext encode the wall time seconds, wall time nanoseconds,
+	// and optional monotonic clock reading in nanoseconds.
+	//
+	// From high to low bit position, wall encodes a 1-bit flag (hasMonotonic),
+	// a 33-bit seconds field, and a 30-bit wall time nanoseconds field.
+	// The nanoseconds field is in the range [0, 999999999].
+	// If the hasMonotonic bit is 0, then the 33-bit field must be zero
+	// and the full signed 64-bit wall seconds since Jan 1 year 1 is stored in ext.
+	// If the hasMonotonic bit is 1, then the 33-bit field holds a 33-bit
+	// unsigned wall seconds since Jan 1 year 1885, and ext holds a
+	// signed 64-bit monotonic clock reading, nanoseconds since process start.
+	wall uint64
+	ext  int64
+
+	// loc specifies the Location that should be used to
+	// determine the minute, hour, month, day, and year
+	// that correspond to this Time.
+	// The nil location means UTC.
+	// All UTC times are represented with loc==nil, never loc==&utcLoc.
+	loc *Location
+}
+
+const (
+	hasMonotonic = 1 << 63
+	maxWall      = wallToInternal + (1<<33 - 1) // year 2157
+	minWall      = wallToInternal               // year 1885
+	nsecMask     = 1<<30 - 1
+	nsecShift    = 30
+)
+
+// These helpers for manipulating the wall and monotonic clock readings
+// take pointer receivers, even when they don't modify the time,
+// to make them cheaper to call.
+
+// nsec returns the time's nanoseconds.
+func (t *Time) nsec() int32 {
+	return int32(t.wall & nsecMask)
+}
+
+// sec returns the time's seconds since Jan 1 year 1.
+func (t *Time) sec() int64 {
+	if t.wall&hasMonotonic != 0 {
+		return wallToInternal + int64(t.wall<<1>>(nsecShift+1))
+	}
+	return t.ext
+}
+
+// unixSec returns the time's seconds since Jan 1 1970 (Unix time).
+func (t *Time) unixSec() int64 { return t.sec() + internalToUnix }
+
+// addSec adds d seconds to the time.
+func (t *Time) addSec(d int64) {
+	if t.wall&hasMonotonic != 0 {
+		sec := int64(t.wall << 1 >> (nsecShift + 1))
+		dsec := sec + d
+		if 0 <= dsec && dsec <= 1<<33-1 {
+			t.wall = t.wall&nsecMask | uint64(dsec)<<nsecShift | hasMonotonic
+			return
+		}
+		// Wall second now out of range for packed field.
+		// Move to ext.
+		t.stripMono()
+	}
+
+	// Check if the sum of t.ext and d overflows and handle it properly.
+	sum := t.ext + d
+	if (sum > t.ext) == (d > 0) {
+		t.ext = sum
+	} else if d > 0 {
+		t.ext = 1<<63 - 1
+	} else {
+		t.ext = -(1<<63 - 1)
+	}
+}
+
+// setLoc sets the location associated with the time.
+func (t *Time) setLoc(loc *Location) {
+	if loc == &utcLoc {
+		loc = nil
+	}
+	t.stripMono()
+	t.loc = loc
+}
+
+// stripMono strips the monotonic clock reading in t.
+func (t *Time) stripMono() {
+	if t.wall&hasMonotonic != 0 {
+		t.ext = t.sec()
+		t.wall &= nsecMask
+	}
+}
+
+// setMono sets the monotonic clock reading in t.
+// If t cannot hold a monotonic clock reading,
+// because its wall time is too large,
+// setMono is a no-op.
+func (t *Time) setMono(m int64) {
+	if t.wall&hasMonotonic == 0 {
+		sec := t.ext
+		if sec < minWall || maxWall < sec {
+			return
+		}
+		t.wall |= hasMonotonic | uint64(sec-minWall)<<nsecShift
+	}
+	t.ext = m
+}
+
+// mono returns t's monotonic clock reading.
+// It returns 0 for a missing reading.
+// This function is used only for testing,
+// so it's OK that technically 0 is a valid
+// monotonic clock reading as well.
+func (t *Time) mono() int64 {
+	if t.wall&hasMonotonic == 0 {
+		return 0
+	}
+	return t.ext
+}
+
+// After reports whether the time instant t is after u.
+func (t Time) After(u Time) bool {
+	if t.wall&u.wall&hasMonotonic != 0 {
+		return t.ext > u.ext
+	}
+	ts := t.sec()
+	us := u.sec()
+	return ts > us || ts == us && t.nsec() > u.nsec()
+}
+
+// Before reports whether the time instant t is before u.
+func (t Time) Before(u Time) bool {
+	if t.wall&u.wall&hasMonotonic != 0 {
+		return t.ext < u.ext
+	}
+	ts := t.sec()
+	us := u.sec()
+	return ts < us || ts == us && t.nsec() < u.nsec()
+}
+
+// Equal reports whether t and u represent the same time instant.
+// Two times can be equal even if they are in different locations.
+// For example, 6:00 +0200 and 4:00 UTC are Equal.
+// See the documentation on the Time type for the pitfalls of using == with
+// Time values; most code should use Equal instead.
+func (t Time) Equal(u Time) bool {
+	if t.wall&u.wall&hasMonotonic != 0 {
+		return t.ext == u.ext
+	}
+	return t.sec() == u.sec() && t.nsec() == u.nsec()
+}
+
+// A Month specifies a month of the year (January = 1, ...).
+type Month int
+
+const (
+	January Month = 1 + iota
+	February
+	March
+	April
+	May
+	June
+	July
+	August
+	September
+	October
+	November
+	December
+)
+
+// String returns the English name of the month ("January", "February", ...).
+func (m Month) String() string {
+	if January <= m && m <= December {
+		return longMonthNames[m-1]
+	}
+	buf := make([]byte, 20)
+	n := fmtInt(buf, uint64(m))
+	return "%!Month(" + string(buf[n:]) + ")"
+}
+
+// A Weekday specifies a day of the week (Sunday = 0, ...).
+type Weekday int
+
+const (
+	Sunday Weekday = iota
+	Monday
+	Tuesday
+	Wednesday
+	Thursday
+	Friday
+	Saturday
+)
+
+// String returns the English name of the day ("Sunday", "Monday", ...).
+func (d Weekday) String() string {
+	if Sunday <= d && d <= Saturday {
+		return longDayNames[d]
+	}
+	buf := make([]byte, 20)
+	n := fmtInt(buf, uint64(d))
+	return "%!Weekday(" + string(buf[n:]) + ")"
+}
+
+// Computations on time.
+//
+// The zero value for a Time is defined to be
+//	January 1, year 1, 00:00:00.000000000 UTC
+// which (1) looks like a zero, or as close as you can get in a date
+// (1-1-1 00:00:00 UTC), (2) is unlikely enough to arise in practice to
+// be a suitable "not set" sentinel, unlike Jan 1 1970, and (3) has a
+// non-negative year even in time zones west of UTC, unlike 1-1-0
+// 00:00:00 UTC, which would be 12-31-(-1) 19:00:00 in New York.
+//
+// The zero Time value does not force a specific epoch for the time
+// representation. For example, to use the Unix epoch internally, we
+// could define that to distinguish a zero value from Jan 1 1970, that
+// time would be represented by sec=-1, nsec=1e9. However, it does
+// suggest a representation, namely using 1-1-1 00:00:00 UTC as the
+// epoch, and that's what we do.
+//
+// The Add and Sub computations are oblivious to the choice of epoch.
+//
+// The presentation computations - year, month, minute, and so on - all
+// rely heavily on division and modulus by positive constants. For
+// calendrical calculations we want these divisions to round down, even
+// for negative values, so that the remainder is always positive, but
+// Go's division (like most hardware division instructions) rounds to
+// zero. We can still do those computations and then adjust the result
+// for a negative numerator, but it's annoying to write the adjustment
+// over and over. Instead, we can change to a different epoch so long
+// ago that all the times we care about will be positive, and then round
+// to zero and round down coincide. These presentation routines already
+// have to add the zone offset, so adding the translation to the
+// alternate epoch is cheap. For example, having a non-negative time t
+// means that we can write
+//
+//	sec = t % 60
+//
+// instead of
+//
+//	sec = t % 60
+//	if sec < 0 {
+//		sec += 60
+//	}
+//
+// everywhere.
+//
+// The calendar runs on an exact 400 year cycle: a 400-year calendar
+// printed for 1970-2369 will apply as well to 2370-2769. Even the days
+// of the week match up. It simplifies the computations to choose the
+// cycle boundaries so that the exceptional years are always delayed as
+// long as possible. That means choosing a year equal to 1 mod 400, so
+// that the first leap year is the 4th year, the first missed leap year
+// is the 100th year, and the missed missed leap year is the 400th year.
+// So we'd prefer instead to print a calendar for 2001-2400 and reuse it
+// for 2401-2800.
+//
+// Finally, it's convenient if the delta between the Unix epoch and
+// long-ago epoch is representable by an int64 constant.
+//
+// These three considerations—choose an epoch as early as possible, that
+// uses a year equal to 1 mod 400, and that is no more than 2⁶³ seconds
+// earlier than 1970—bring us to the year -292277022399. We refer to
+// this year as the absolute zero year, and to times measured as a uint64
+// seconds since this year as absolute times.
+//
+// Times measured as an int64 seconds since the year 1—the representation
+// used for Time's sec field—are called internal times.
+//
+// Times measured as an int64 seconds since the year 1970 are called Unix
+// times.
+//
+// It is tempting to just use the year 1 as the absolute epoch, defining
+// that the routines are only valid for years >= 1. However, the
+// routines would then be invalid when displaying the epoch in time zones
+// west of UTC, since it is year 0. It doesn't seem tenable to say that
+// printing the zero time correctly isn't supported in half the time
+// zones. By comparison, it's reasonable to mishandle some times in
+// the year -292277022399.
+//
+// All this is opaque to clients of the API and can be changed if a
+// better implementation presents itself.
+
+const (
+	// The unsigned zero year for internal calculations.
+	// Must be 1 mod 400, and times before it will not compute correctly,
+	// but otherwise can be changed at will.
+	absoluteZeroYear = -292277022399
+
+	// The year of the zero Time.
+	// Assumed by the unixToInternal computation below.
+	internalYear = 1
+
+	// Offsets to convert between internal and absolute or Unix times.
+	absoluteToInternal int64 = (absoluteZeroYear - internalYear) * 365.2425 * secondsPerDay
+	internalToAbsolute       = -absoluteToInternal
+
+	unixToInternal int64 = (1969*365 + 1969/4 - 1969/100 + 1969/400) * secondsPerDay
+	internalToUnix int64 = -unixToInternal
+
+	wallToInternal int64 = (1884*365 + 1884/4 - 1884/100 + 1884/400) * secondsPerDay
+)
+
+// IsZero reports whether t represents the zero time instant,
+// January 1, year 1, 00:00:00 UTC.
+func (t Time) IsZero() bool {
+	return t.sec() == 0 && t.nsec() == 0
+}
+
+// abs returns the time t as an absolute time, adjusted by the zone offset.
+// It is called when computing a presentation property like Month or Hour.
+func (t Time) abs() uint64 {
+	l := t.loc
+	// Avoid function calls when possible.
+	if l == nil || l == &localLoc {
+		l = l.get()
+	}
+	sec := t.unixSec()
+	if l != &utcLoc {
+		if l.cacheZone != nil && l.cacheStart <= sec && sec < l.cacheEnd {
+			sec += int64(l.cacheZone.offset)
+		} else {
+			_, offset, _, _, _ := l.lookup(sec)
+			sec += int64(offset)
+		}
+	}
+	return uint64(sec + (unixToInternal + internalToAbsolute))
+}
+
+// locabs is a combination of the Zone and abs methods,
+// extracting both return values from a single zone lookup.
+func (t Time) locabs() (name string, offset int, abs uint64) {
+	l := t.loc
+	if l == nil || l == &localLoc {
+		l = l.get()
+	}
+	// Avoid function call if we hit the local time cache.
+	sec := t.unixSec()
+	if l != &utcLoc {
+		if l.cacheZone != nil && l.cacheStart <= sec && sec < l.cacheEnd {
+			name = l.cacheZone.name
+			offset = l.cacheZone.offset
+		} else {
+			name, offset, _, _, _ = l.lookup(sec)
+		}
+		sec += int64(offset)
+	} else {
+		name = "UTC"
+	}
+	abs = uint64(sec + (unixToInternal + internalToAbsolute))
+	return
+}
+
+// Date returns the year, month, and day in which t occurs.
+func (t Time) Date() (year int, month Month, day int) {
+	year, month, day, _ = t.date(true)
+	return
+}
+
+// Year returns the year in which t occurs.
+func (t Time) Year() int {
+	year, _, _, _ := t.date(false)
+	return year
+}
+
+// Month returns the month of the year specified by t.
+func (t Time) Month() Month {
+	_, month, _, _ := t.date(true)
+	return month
+}
+
+// Day returns the day of the month specified by t.
+func (t Time) Day() int {
+	_, _, day, _ := t.date(true)
+	return day
+}
+
+// Weekday returns the day of the week specified by t.
+func (t Time) Weekday() Weekday {
+	return absWeekday(t.abs())
+}
+
+// absWeekday is like Weekday but operates on an absolute time.
+func absWeekday(abs uint64) Weekday {
+	// January 1 of the absolute year, like January 1 of 2001, was a Monday.
+	sec := (abs + uint64(Monday)*secondsPerDay) % secondsPerWeek
+	return Weekday(int(sec) / secondsPerDay)
+}
+
+// ISOWeek returns the ISO 8601 year and week number in which t occurs.
+// Week ranges from 1 to 53. Jan 01 to Jan 03 of year n might belong to
+// week 52 or 53 of year n-1, and Dec 29 to Dec 31 might belong to week 1
+// of year n+1.
+func (t Time) ISOWeek() (year, week int) {
+	// According to the rule that the first calendar week of a calendar year is
+	// the week including the first Thursday of that year, and that the last one is
+	// the week immediately preceding the first calendar week of the next calendar year.
+	// See https://www.iso.org/obp/ui#iso:std:iso:8601:-1:ed-1:v1:en:term:3.1.1.23 for details.
+
+	// weeks start with Monday
+	// Monday Tuesday Wednesday Thursday Friday Saturday Sunday
+	// 1      2       3         4        5      6        7
+	// +3     +2      +1        0        -1     -2       -3
+	// the offset to Thursday
+	abs := t.abs()
+	d := Thursday - absWeekday(abs)
+	// handle Sunday
+	if d == 4 {
+		d = -3
+	}
+	// find the Thursday of the calendar week
+	abs += uint64(d) * secondsPerDay
+	year, _, _, yday := absDate(abs, false)
+	return year, yday/7 + 1
+}
+
+// Clock returns the hour, minute, and second within the day specified by t.
+func (t Time) Clock() (hour, min, sec int) {
+	return absClock(t.abs())
+}
+
+// absClock is like clock but operates on an absolute time.
+func absClock(abs uint64) (hour, min, sec int) {
+	sec = int(abs % secondsPerDay)
+	hour = sec / secondsPerHour
+	sec -= hour * secondsPerHour
+	min = sec / secondsPerMinute
+	sec -= min * secondsPerMinute
+	return
+}
+
+// Hour returns the hour within the day specified by t, in the range [0, 23].
+func (t Time) Hour() int {
+	return int(t.abs()%secondsPerDay) / secondsPerHour
+}
+
+// Minute returns the minute offset within the hour specified by t, in the range [0, 59].
+func (t Time) Minute() int {
+	return int(t.abs()%secondsPerHour) / secondsPerMinute
+}
+
+// Second returns the second offset within the minute specified by t, in the range [0, 59].
+func (t Time) Second() int {
+	return int(t.abs() % secondsPerMinute)
+}
+
+// Nanosecond returns the nanosecond offset within the second specified by t,
+// in the range [0, 999999999].
+func (t Time) Nanosecond() int {
+	return int(t.nsec())
+}
+
+// YearDay returns the day of the year specified by t, in the range [1,365] for non-leap years,
+// and [1,366] in leap years.
+func (t Time) YearDay() int {
+	_, _, _, yday := t.date(false)
+	return yday + 1
+}
+
+// A Duration represents the elapsed time between two instants
+// as an int64 nanosecond count. The representation limits the
+// largest representable duration to approximately 290 years.
+type Duration int64
+
+const (
+	minDuration Duration = -1 << 63
+	maxDuration Duration = 1<<63 - 1
+)
+
+// Common durations. There is no definition for units of Day or larger
+// to avoid confusion across daylight savings time zone transitions.
+//
+// To count the number of units in a Duration, divide:
+//
+//	second := time.Second
+//	fmt.Print(int64(second/time.Millisecond)) // prints 1000
+//
+// To convert an integer number of units to a Duration, multiply:
+//
+//	seconds := 10
+//	fmt.Print(time.Duration(seconds)*time.Second) // prints 10s
+const (
+	Nanosecond  Duration = 1
+	Microsecond          = 1000 * Nanosecond
+	Millisecond          = 1000 * Microsecond
+	Second               = 1000 * Millisecond
+	Minute               = 60 * Second
+	Hour                 = 60 * Minute
+)
+
+// String returns a string representing the duration in the form "72h3m0.5s".
+// Leading zero units are omitted. As a special case, durations less than one
+// second format use a smaller unit (milli-, micro-, or nanoseconds) to ensure
+// that the leading digit is non-zero. The zero duration formats as 0s.
+func (d Duration) String() string {
+	// Largest time is 2540400h10m10.000000000s
+	var buf [32]byte
+	w := len(buf)
+
+	u := uint64(d)
+	neg := d < 0
+	if neg {
+		u = -u
+	}
+
+	if u < uint64(Second) {
+		// Special case: if duration is smaller than a second,
+		// use smaller units, like 1.2ms
+		var prec int
+		w--
+		buf[w] = 's'
+		w--
+		switch {
+		case u == 0:
+			return "0s"
+		case u < uint64(Microsecond):
+			// print nanoseconds
+			prec = 0
+			buf[w] = 'n'
+		case u < uint64(Millisecond):
+			// print microseconds
+			prec = 3
+			// U+00B5 'µ' micro sign == 0xC2 0xB5
+			w-- // Need room for two bytes.
+			copy(buf[w:], "µ")
+		default:
+			// print milliseconds
+			prec = 6
+			buf[w] = 'm'
+		}
+		w, u = fmtFrac(buf[:w], u, prec)
+		w = fmtInt(buf[:w], u)
+	} else {
+		w--
+		buf[w] = 's'
+
+		w, u = fmtFrac(buf[:w], u, 9)
+
+		// u is now integer seconds
+		w = fmtInt(buf[:w], u%60)
+		u /= 60
+
+		// u is now integer minutes
+		if u > 0 {
+			w--
+			buf[w] = 'm'
+			w = fmtInt(buf[:w], u%60)
+			u /= 60
+
+			// u is now integer hours
+			// Stop at hours because days can be different lengths.
+			if u > 0 {
+				w--
+				buf[w] = 'h'
+				w = fmtInt(buf[:w], u)
+			}
+		}
+	}
+
+	if neg {
+		w--
+		buf[w] = '-'
+	}
+
+	return string(buf[w:])
+}
+
+// fmtFrac formats the fraction of v/10**prec (e.g., ".12345") into the
+// tail of buf, omitting trailing zeros. It omits the decimal
+// point too when the fraction is 0. It returns the index where the
+// output bytes begin and the value v/10**prec.
+func fmtFrac(buf []byte, v uint64, prec int) (nw int, nv uint64) {
+	// Omit trailing zeros up to and including decimal point.
+	w := len(buf)
+	print := false
+	for i := 0; i < prec; i++ {
+		digit := v % 10
+		print = print || digit != 0
+		if print {
+			w--
+			buf[w] = byte(digit) + '0'
+		}
+		v /= 10
+	}
+	if print {
+		w--
+		buf[w] = '.'
+	}
+	return w, v
+}
+
+// fmtInt formats v into the tail of buf.
+// It returns the index where the output begins.
+func fmtInt(buf []byte, v uint64) int {
+	w := len(buf)
+	if v == 0 {
+		w--
+		buf[w] = '0'
+	} else {
+		for v > 0 {
+			w--
+			buf[w] = byte(v%10) + '0'
+			v /= 10
+		}
+	}
+	return w
+}
+
+// Nanoseconds returns the duration as an integer nanosecond count.
+func (d Duration) Nanoseconds() int64 { return int64(d) }
+
+// Microseconds returns the duration as an integer microsecond count.
+func (d Duration) Microseconds() int64 { return int64(d) / 1e3 }
+
+// Milliseconds returns the duration as an integer millisecond count.
+func (d Duration) Milliseconds() int64 { return int64(d) / 1e6 }
+
+// These methods return float64 because the dominant
+// use case is for printing a floating point number like 1.5s, and
+// a truncation to integer would make them not useful in those cases.
+// Splitting the integer and fraction ourselves guarantees that
+// converting the returned float64 to an integer rounds the same
+// way that a pure integer conversion would have, even in cases
+// where, say, float64(d.Nanoseconds())/1e9 would have rounded
+// differently.
+
+// Seconds returns the duration as a floating point number of seconds.
+func (d Duration) Seconds() float64 {
+	sec := d / Second
+	nsec := d % Second
+	return float64(sec) + float64(nsec)/1e9
+}
+
+// Minutes returns the duration as a floating point number of minutes.
+func (d Duration) Minutes() float64 {
+	min := d / Minute
+	nsec := d % Minute
+	return float64(min) + float64(nsec)/(60*1e9)
+}
+
+// Hours returns the duration as a floating point number of hours.
+func (d Duration) Hours() float64 {
+	hour := d / Hour
+	nsec := d % Hour
+	return float64(hour) + float64(nsec)/(60*60*1e9)
+}
+
+// Truncate returns the result of rounding d toward zero to a multiple of m.
+// If m <= 0, Truncate returns d unchanged.
+func (d Duration) Truncate(m Duration) Duration {
+	if m <= 0 {
+		return d
+	}
+	return d - d%m
+}
+
+// lessThanHalf reports whether x+x < y but avoids overflow,
+// assuming x and y are both positive (Duration is signed).
+func lessThanHalf(x, y Duration) bool {
+	return uint64(x)+uint64(x) < uint64(y)
+}
+
+// Round returns the result of rounding d to the nearest multiple of m.
+// The rounding behavior for halfway values is to round away from zero.
+// If the result exceeds the maximum (or minimum)
+// value that can be stored in a Duration,
+// Round returns the maximum (or minimum) duration.
+// If m <= 0, Round returns d unchanged.
+func (d Duration) Round(m Duration) Duration {
+	if m <= 0 {
+		return d
+	}
+	r := d % m
+	if d < 0 {
+		r = -r
+		if lessThanHalf(r, m) {
+			return d + r
+		}
+		if d1 := d - m + r; d1 < d {
+			return d1
+		}
+		return minDuration // overflow
+	}
+	if lessThanHalf(r, m) {
+		return d - r
+	}
+	if d1 := d + m - r; d1 > d {
+		return d1
+	}
+	return maxDuration // overflow
+}
+
+// Abs returns the absolute value of d.
+// As a special case, math.MinInt64 is converted to math.MaxInt64.
+func (d Duration) Abs() Duration {
+	switch {
+	case d >= 0:
+		return d
+	case d == minDuration:
+		return maxDuration
+	default:
+		return -d
+	}
+}
+
+// Add returns the time t+d.
+func (t Time) Add(d Duration) Time {
+	dsec := int64(d / 1e9)
+	nsec := t.nsec() + int32(d%1e9)
+	if nsec >= 1e9 {
+		dsec++
+		nsec -= 1e9
+	} else if nsec < 0 {
+		dsec--
+		nsec += 1e9
+	}
+	t.wall = t.wall&^nsecMask | uint64(nsec) // update nsec
+	t.addSec(dsec)
+	if t.wall&hasMonotonic != 0 {
+		te := t.ext + int64(d)
+		if d < 0 && te > t.ext || d > 0 && te < t.ext {
+			// Monotonic clock reading now out of range; degrade to wall-only.
+			t.stripMono()
+		} else {
+			t.ext = te
+		}
+	}
+	return t
+}
+
+// Sub returns the duration t-u. If the result exceeds the maximum (or minimum)
+// value that can be stored in a Duration, the maximum (or minimum) duration
+// will be returned.
+// To compute t-d for a duration d, use t.Add(-d).
+func (t Time) Sub(u Time) Duration {
+	if t.wall&u.wall&hasMonotonic != 0 {
+		te := t.ext
+		ue := u.ext
+		d := Duration(te - ue)
+		if d < 0 && te > ue {
+			return maxDuration // t - u is positive out of range
+		}
+		if d > 0 && te < ue {
+			return minDuration // t - u is negative out of range
+		}
+		return d
+	}
+	d := Duration(t.sec()-u.sec())*Second + Duration(t.nsec()-u.nsec())
+	// Check for overflow or underflow.
+	switch {
+	case u.Add(d).Equal(t):
+		return d // d is correct
+	case t.Before(u):
+		return minDuration // t - u is negative out of range
+	default:
+		return maxDuration // t - u is positive out of range
+	}
+}
+
+// Since returns the time elapsed since t.
+// It is shorthand for time.Now().Sub(t).
+func Since(t Time) Duration {
+	var now Time
+	if t.wall&hasMonotonic != 0 {
+		// Common case optimization: if t has monotonic time, then Sub will use only it.
+		now = Time{hasMonotonic, runtimeNano() - startNano, nil}
+	} else {
+		now = Now()
+	}
+	return now.Sub(t)
+}
+
+// Until returns the duration until t.
+// It is shorthand for t.Sub(time.Now()).
+func Until(t Time) Duration {
+	var now Time
+	if t.wall&hasMonotonic != 0 {
+		// Common case optimization: if t has monotonic time, then Sub will use only it.
+		now = Time{hasMonotonic, runtimeNano() - startNano, nil}
+	} else {
+		now = Now()
+	}
+	return t.Sub(now)
+}
+
+// AddDate returns the time corresponding to adding the
+// given number of years, months, and days to t.
+// For example, AddDate(-1, 2, 3) applied to January 1, 2011
+// returns March 4, 2010.
+//
+// AddDate normalizes its result in the same way that Date does,
+// so, for example, adding one month to October 31 yields
+// December 1, the normalized form for November 31.
+func (t Time) AddDate(years int, months int, days int) Time {
+	year, month, day := t.Date()
+	hour, min, sec := t.Clock()
+	return Date(year+years, month+Month(months), day+days, hour, min, sec, int(t.nsec()), t.Location())
+}
+
+const (
+	secondsPerMinute = 60
+	secondsPerHour   = 60 * secondsPerMinute
+	secondsPerDay    = 24 * secondsPerHour
+	secondsPerWeek   = 7 * secondsPerDay
+	daysPer400Years  = 365*400 + 97
+	daysPer100Years  = 365*100 + 24
+	daysPer4Years    = 365*4 + 1
+)
+
+// date computes the year, day of year, and when full=true,
+// the month and day in which t occurs.
+func (t Time) date(full bool) (year int, month Month, day int, yday int) {
+	return absDate(t.abs(), full)
+}
+
+// absDate is like date but operates on an absolute time.
+func absDate(abs uint64, full bool) (year int, month Month, day int, yday int) {
+	// Split into time and day.
+	d := abs / secondsPerDay
+
+	// Account for 400 year cycles.
+	n := d / daysPer400Years
+	y := 400 * n
+	d -= daysPer400Years * n
+
+	// Cut off 100-year cycles.
+	// The last cycle has one extra leap year, so on the last day
+	// of that year, day / daysPer100Years will be 4 instead of 3.
+	// Cut it back down to 3 by subtracting n>>2.
+	n = d / daysPer100Years
+	n -= n >> 2
+	y += 100 * n
+	d -= daysPer100Years * n
+
+	// Cut off 4-year cycles.
+	// The last cycle has a missing leap year, which does not
+	// affect the computation.
+	n = d / daysPer4Years
+	y += 4 * n
+	d -= daysPer4Years * n
+
+	// Cut off years within a 4-year cycle.
+	// The last year is a leap year, so on the last day of that year,
+	// day / 365 will be 4 instead of 3. Cut it back down to 3
+	// by subtracting n>>2.
+	n = d / 365
+	n -= n >> 2
+	y += n
+	d -= 365 * n
+
+	year = int(int64(y) + absoluteZeroYear)
+	yday = int(d)
+
+	if !full {
+		return
+	}
+
+	day = yday
+	if isLeap(year) {
+		// Leap year
+		switch {
+		case day > 31+29-1:
+			// After leap day; pretend it wasn't there.
+			day--
+		case day == 31+29-1:
+			// Leap day.
+			month = February
+			day = 29
+			return
+		}
+	}
+
+	// Estimate month on assumption that every month has 31 days.
+	// The estimate may be too low by at most one month, so adjust.
+	month = Month(day / 31)
+	end := int(daysBefore[month+1])
+	var begin int
+	if day >= end {
+		month++
+		begin = end
+	} else {
+		begin = int(daysBefore[month])
+	}
+
+	month++ // because January is 1
+	day = day - begin + 1
+	return
+}
+
+// daysBefore[m] counts the number of days in a non-leap year
+// before month m begins. There is an entry for m=12, counting
+// the number of days before January of next year (365).
+var daysBefore = [...]int32{
+	0,
+	31,
+	31 + 28,
+	31 + 28 + 31,
+	31 + 28 + 31 + 30,
+	31 + 28 + 31 + 30 + 31,
+	31 + 28 + 31 + 30 + 31 + 30,
+	31 + 28 + 31 + 30 + 31 + 30 + 31,
+	31 + 28 + 31 + 30 + 31 + 30 + 31 + 31,
+	31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30,
+	31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31,
+	31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31 + 30,
+	31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31 + 30 + 31,
+}
+
+func daysIn(m Month, year int) int {
+	if m == February && isLeap(year) {
+		return 29
+	}
+	return int(daysBefore[m] - daysBefore[m-1])
+}
+
+// daysSinceEpoch takes a year and returns the number of days from
+// the absolute epoch to the start of that year.
+// This is basically (year - zeroYear) * 365, but accounting for leap days.
+func daysSinceEpoch(year int) uint64 {
+	y := uint64(int64(year) - absoluteZeroYear)
+
+	// Add in days from 400-year cycles.
+	n := y / 400
+	y -= 400 * n
+	d := daysPer400Years * n
+
+	// Add in 100-year cycles.
+	n = y / 100
+	y -= 100 * n
+	d += daysPer100Years * n
+
+	// Add in 4-year cycles.
+	n = y / 4
+	y -= 4 * n
+	d += daysPer4Years * n
+
+	// Add in non-leap years.
+	n = y
+	d += 365 * n
+
+	return d
+}
+
+// Provided by package runtime.
+func now() (sec int64, nsec int32, mono int64)
+
+// runtimeNano returns the current value of the runtime clock in nanoseconds.
+//
+//go:linkname runtimeNano runtime.nanotime
+func runtimeNano() int64
+
+// Monotonic times are reported as offsets from startNano.
+// We initialize startNano to runtimeNano() - 1 so that on systems where
+// monotonic time resolution is fairly low (e.g. Windows 2008
+// which appears to have a default resolution of 15ms),
+// we avoid ever reporting a monotonic time of 0.
+// (Callers may want to use 0 as "time not set".)
+var startNano int64 = runtimeNano() - 1
+
+// Now returns the current local time.
+func Now() Time {
+	sec, nsec, mono := now()
+	mono -= startNano
+	sec += unixToInternal - minWall
+	if uint64(sec)>>33 != 0 {
+		return Time{uint64(nsec), sec + minWall, Local}
+	}
+	return Time{hasMonotonic | uint64(sec)<<nsecShift | uint64(nsec), mono, Local}
+}
+
+func unixTime(sec int64, nsec int32) Time {
+	return Time{uint64(nsec), sec + unixToInternal, Local}
+}
+
+// UTC returns t with the location set to UTC.
+func (t Time) UTC() Time {
+	t.setLoc(&utcLoc)
+	return t
+}
+
+// Local returns t with the location set to local time.
+func (t Time) Local() Time {
+	t.setLoc(Local)
+	return t
+}
+
+// In returns a copy of t representing the same time instant, but
+// with the copy's location information set to loc for display
+// purposes.
+//
+// In panics if loc is nil.
+func (t Time) In(loc *Location) Time {
+	if loc == nil {
+		panic("time: missing Location in call to Time.In")
+	}
+	t.setLoc(loc)
+	return t
+}
+
+// Location returns the time zone information associated with t.
+func (t Time) Location() *Location {
+	l := t.loc
+	if l == nil {
+		l = UTC
+	}
+	return l
+}
+
+// Zone computes the time zone in effect at time t, returning the abbreviated
+// name of the zone (such as "CET") and its offset in seconds east of UTC.
+func (t Time) Zone() (name string, offset int) {
+	name, offset, _, _, _ = t.loc.lookup(t.unixSec())
+	return
+}
+
+// ZoneBounds returns the bounds of the time zone in effect at time t.
+// The zone begins at start and the next zone begins at end.
+// If the zone begins at the beginning of time, start will be returned as a zero Time.
+// If the zone goes on forever, end will be returned as a zero Time.
+// The Location of the returned times will be the same as t.
+func (t Time) ZoneBounds() (start, end Time) {
+	_, _, startSec, endSec, _ := t.loc.lookup(t.unixSec())
+	if startSec != alpha {
+		start = unixTime(startSec, 0)
+		start.setLoc(t.loc)
+	}
+	if endSec != omega {
+		end = unixTime(endSec, 0)
+		end.setLoc(t.loc)
+	}
+	return
+}
+
+// Unix returns t as a Unix time, the number of seconds elapsed
+// since January 1, 1970 UTC. The result does not depend on the
+// location associated with t.
+// Unix-like operating systems often record time as a 32-bit
+// count of seconds, but since the method here returns a 64-bit
+// value it is valid for billions of years into the past or future.
+func (t Time) Unix() int64 {
+	return t.unixSec()
+}
+
+// UnixMilli returns t as a Unix time, the number of milliseconds elapsed since
+// January 1, 1970 UTC. The result is undefined if the Unix time in
+// milliseconds cannot be represented by an int64 (a date more than 292 million
+// years before or after 1970). The result does not depend on the
+// location associated with t.
+func (t Time) UnixMilli() int64 {
+	return t.unixSec()*1e3 + int64(t.nsec())/1e6
+}
+
+// UnixMicro returns t as a Unix time, the number of microseconds elapsed since
+// January 1, 1970 UTC. The result is undefined if the Unix time in
+// microseconds cannot be represented by an int64 (a date before year -290307 or
+// after year 294246). The result does not depend on the location associated
+// with t.
+func (t Time) UnixMicro() int64 {
+	return t.unixSec()*1e6 + int64(t.nsec())/1e3
+}
+
+// UnixNano returns t as a Unix time, the number of nanoseconds elapsed
+// since January 1, 1970 UTC. The result is undefined if the Unix time
+// in nanoseconds cannot be represented by an int64 (a date before the year
+// 1678 or after 2262). Note that this means the result of calling UnixNano
+// on the zero Time is undefined. The result does not depend on the
+// location associated with t.
+func (t Time) UnixNano() int64 {
+	return (t.unixSec())*1e9 + int64(t.nsec())
+}
+
+const (
+	timeBinaryVersionV1 byte = iota + 1 // For general situation
+	timeBinaryVersionV2                 // For LMT only
+)
+
+// MarshalBinary implements the encoding.BinaryMarshaler interface.
+func (t Time) MarshalBinary() ([]byte, error) {
+	var offsetMin int16 // minutes east of UTC. -1 is UTC.
+	var offsetSec int8
+	version := timeBinaryVersionV1
+
+	if t.Location() == UTC {
+		offsetMin = -1
+	} else {
+		_, offset := t.Zone()
+		if offset%60 != 0 {
+			version = timeBinaryVersionV2
+			offsetSec = int8(offset % 60)
+		}
+
+		offset /= 60
+		if offset < -32768 || offset == -1 || offset > 32767 {
+			return nil, errors.New("Time.MarshalBinary: unexpected zone offset")
+		}
+		offsetMin = int16(offset)
+	}
+
+	sec := t.sec()
+	nsec := t.nsec()
+	enc := []byte{
+		version,         // byte 0 : version
+		byte(sec >> 56), // bytes 1-8: seconds
+		byte(sec >> 48),
+		byte(sec >> 40),
+		byte(sec >> 32),
+		byte(sec >> 24),
+		byte(sec >> 16),
+		byte(sec >> 8),
+		byte(sec),
+		byte(nsec >> 24), // bytes 9-12: nanoseconds
+		byte(nsec >> 16),
+		byte(nsec >> 8),
+		byte(nsec),
+		byte(offsetMin >> 8), // bytes 13-14: zone offset in minutes
+		byte(offsetMin),
+	}
+	if version == timeBinaryVersionV2 {
+		enc = append(enc, byte(offsetSec))
+	}
+
+	return enc, nil
+}
+
+// UnmarshalBinary implements the encoding.BinaryUnmarshaler interface.
+func (t *Time) UnmarshalBinary(data []byte) error {
+	buf := data
+	if len(buf) == 0 {
+		return errors.New("Time.UnmarshalBinary: no data")
+	}
+
+	version := buf[0]
+	if version != timeBinaryVersionV1 && version != timeBinaryVersionV2 {
+		return errors.New("Time.UnmarshalBinary: unsupported version")
+	}
+
+	wantLen := /*version*/ 1 + /*sec*/ 8 + /*nsec*/ 4 + /*zone offset*/ 2
+	if version == timeBinaryVersionV2 {
+		wantLen++
+	}
+	if len(buf) != wantLen {
+		return errors.New("Time.UnmarshalBinary: invalid length")
+	}
+
+	buf = buf[1:]
+	sec := int64(buf[7]) | int64(buf[6])<<8 | int64(buf[5])<<16 | int64(buf[4])<<24 |
+		int64(buf[3])<<32 | int64(buf[2])<<40 | int64(buf[1])<<48 | int64(buf[0])<<56
+
+	buf = buf[8:]
+	nsec := int32(buf[3]) | int32(buf[2])<<8 | int32(buf[1])<<16 | int32(buf[0])<<24
+
+	buf = buf[4:]
+	offset := int(int16(buf[1])|int16(buf[0])<<8) * 60
+	if version == timeBinaryVersionV2 {
+		offset += int(buf[2])
+	}
+
+	*t = Time{}
+	t.wall = uint64(nsec)
+	t.ext = sec
+
+	if offset == -1*60 {
+		t.setLoc(&utcLoc)
+	} else if _, localoff, _, _, _ := Local.lookup(t.unixSec()); offset == localoff {
+		t.setLoc(Local)
+	} else {
+		t.setLoc(FixedZone("", offset))
+	}
+
+	return nil
+}
+
+// TODO(rsc): Remove GobEncoder, GobDecoder, MarshalJSON, UnmarshalJSON in Go 2.
+// The same semantics will be provided by the generic MarshalBinary, MarshalText,
+// UnmarshalBinary, UnmarshalText.
+
+// GobEncode implements the gob.GobEncoder interface.
+func (t Time) GobEncode() ([]byte, error) {
+	return t.MarshalBinary()
+}
+
+// GobDecode implements the gob.GobDecoder interface.
+func (t *Time) GobDecode(data []byte) error {
+	return t.UnmarshalBinary(data)
+}
+
+// MarshalJSON implements the json.Marshaler interface.
+// The time is a quoted string in RFC 3339 format, with sub-second precision added if present.
+func (t Time) MarshalJSON() ([]byte, error) {
+	if y := t.Year(); y < 0 || y >= 10000 {
+		// RFC 3339 is clear that years are 4 digits exactly.
+		// See golang.org/issue/4556#c15 for more discussion.
+		return nil, errors.New("Time.MarshalJSON: year outside of range [0,9999]")
+	}
+
+	b := make([]byte, 0, len(RFC3339Nano)+2)
+	b = append(b, '"')
+	b = t.AppendFormat(b, RFC3339Nano)
+	b = append(b, '"')
+	return b, nil
+}
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+// The time is expected to be a quoted string in RFC 3339 format.
+func (t *Time) UnmarshalJSON(data []byte) error {
+	// Ignore null, like in the main JSON package.
+	if string(data) == "null" {
+		return nil
+	}
+	// Fractional seconds are handled implicitly by Parse.
+	var err error
+	*t, err = Parse(`"`+RFC3339+`"`, string(data))
+	return err
+}
+
+// MarshalText implements the encoding.TextMarshaler interface.
+// The time is formatted in RFC 3339 format, with sub-second precision added if present.
+func (t Time) MarshalText() ([]byte, error) {
+	if y := t.Year(); y < 0 || y >= 10000 {
+		return nil, errors.New("Time.MarshalText: year outside of range [0,9999]")
+	}
+
+	b := make([]byte, 0, len(RFC3339Nano))
+	return t.AppendFormat(b, RFC3339Nano), nil
+}
+
+// UnmarshalText implements the encoding.TextUnmarshaler interface.
+// The time is expected to be in RFC 3339 format.
+func (t *Time) UnmarshalText(data []byte) error {
+	// Fractional seconds are handled implicitly by Parse.
+	var err error
+	*t, err = Parse(RFC3339, string(data))
+	return err
+}
+
+// Unix returns the local Time corresponding to the given Unix time,
+// sec seconds and nsec nanoseconds since January 1, 1970 UTC.
+// It is valid to pass nsec outside the range [0, 999999999].
+// Not all sec values have a corresponding time value. One such
+// value is 1<<63-1 (the largest int64 value).
+func Unix(sec int64, nsec int64) Time {
+	if nsec < 0 || nsec >= 1e9 {
+		n := nsec / 1e9
+		sec += n
+		nsec -= n * 1e9
+		if nsec < 0 {
+			nsec += 1e9
+			sec--
+		}
+	}
+	return unixTime(sec, int32(nsec))
+}
+
+// UnixMilli returns the local Time corresponding to the given Unix time,
+// msec milliseconds since January 1, 1970 UTC.
+func UnixMilli(msec int64) Time {
+	return Unix(msec/1e3, (msec%1e3)*1e6)
+}
+
+// UnixMicro returns the local Time corresponding to the given Unix time,
+// usec microseconds since January 1, 1970 UTC.
+func UnixMicro(usec int64) Time {
+	return Unix(usec/1e6, (usec%1e6)*1e3)
+}
+
+// IsDST reports whether the time in the configured location is in Daylight Savings Time.
+func (t Time) IsDST() bool {
+	_, _, _, _, isDST := t.loc.lookup(t.Unix())
+	return isDST
+}
+
+func isLeap(year int) bool {
+	return year%4 == 0 && (year%100 != 0 || year%400 == 0)
+}
+
+// norm returns nhi, nlo such that
+//
+//	hi * base + lo == nhi * base + nlo
+//	0 <= nlo < base
+func norm(hi, lo, base int) (nhi, nlo int) {
+	if lo < 0 {
+		n := (-lo-1)/base + 1
+		hi -= n
+		lo += n * base
+	}
+	if lo >= base {
+		n := lo / base
+		hi += n
+		lo -= n * base
+	}
+	return hi, lo
+}
+
+// Date returns the Time corresponding to
+//
+//	yyyy-mm-dd hh:mm:ss + nsec nanoseconds
+//
+// in the appropriate zone for that time in the given location.
+//
+// The month, day, hour, min, sec, and nsec values may be outside
+// their usual ranges and will be normalized during the conversion.
+// For example, October 32 converts to November 1.
+//
+// A daylight savings time transition skips or repeats times.
+// For example, in the United States, March 13, 2011 2:15am never occurred,
+// while November 6, 2011 1:15am occurred twice. In such cases, the
+// choice of time zone, and therefore the time, is not well-defined.
+// Date returns a time that is correct in one of the two zones involved
+// in the transition, but it does not guarantee which.
+//
+// Date panics if loc is nil.
+func Date(year int, month Month, day, hour, min, sec, nsec int, loc *Location) Time {
+	if loc == nil {
+		panic("time: missing Location in call to Date")
+	}
+
+	// Normalize month, overflowing into year.
+	m := int(month) - 1
+	year, m = norm(year, m, 12)
+	month = Month(m) + 1
+
+	// Normalize nsec, sec, min, hour, overflowing into day.
+	sec, nsec = norm(sec, nsec, 1e9)
+	min, sec = norm(min, sec, 60)
+	hour, min = norm(hour, min, 60)
+	day, hour = norm(day, hour, 24)
+
+	// Compute days since the absolute epoch.
+	d := daysSinceEpoch(year)
+
+	// Add in days before this month.
+	d += uint64(daysBefore[month-1])
+	if isLeap(year) && month >= March {
+		d++ // February 29
+	}
+
+	// Add in days before today.
+	d += uint64(day - 1)
+
+	// Add in time elapsed today.
+	abs := d * secondsPerDay
+	abs += uint64(hour*secondsPerHour + min*secondsPerMinute + sec)
+
+	unix := int64(abs) + (absoluteToInternal + internalToUnix)
+
+	// Look for zone offset for expected time, so we can adjust to UTC.
+	// The lookup function expects UTC, so first we pass unix in the
+	// hope that it will not be too close to a zone transition,
+	// and then adjust if it is.
+	_, offset, start, end, _ := loc.lookup(unix)
+	if offset != 0 {
+		utc := unix - int64(offset)
+		// If utc is valid for the time zone we found, then we have the right offset.
+		// If not, we get the correct offset by looking up utc in the location.
+		if utc < start || utc >= end {
+			_, offset, _, _, _ = loc.lookup(utc)
+		}
+		unix -= int64(offset)
+	}
+
+	t := unixTime(unix, int32(nsec))
+	t.setLoc(loc)
+	return t
+}
+
+// Truncate returns the result of rounding t down to a multiple of d (since the zero time).
+// If d <= 0, Truncate returns t stripped of any monotonic clock reading but otherwise unchanged.
+//
+// Truncate operates on the time as an absolute duration since the
+// zero time; it does not operate on the presentation form of the
+// time. Thus, Truncate(Hour) may return a time with a non-zero
+// minute, depending on the time's Location.
+func (t Time) Truncate(d Duration) Time {
+	t.stripMono()
+	if d <= 0 {
+		return t
+	}
+	_, r := div(t, d)
+	return t.Add(-r)
+}
+
+// Round returns the result of rounding t to the nearest multiple of d (since the zero time).
+// The rounding behavior for halfway values is to round up.
+// If d <= 0, Round returns t stripped of any monotonic clock reading but otherwise unchanged.
+//
+// Round operates on the time as an absolute duration since the
+// zero time; it does not operate on the presentation form of the
+// time. Thus, Round(Hour) may return a time with a non-zero
+// minute, depending on the time's Location.
+func (t Time) Round(d Duration) Time {
+	t.stripMono()
+	if d <= 0 {
+		return t
+	}
+	_, r := div(t, d)
+	if lessThanHalf(r, d) {
+		return t.Add(-r)
+	}
+	return t.Add(d - r)
+}
+
+// div divides t by d and returns the quotient parity and remainder.
+// We don't use the quotient parity anymore (round half up instead of round to even)
+// but it's still here in case we change our minds.
+func div(t Time, d Duration) (qmod2 int, r Duration) {
+	neg := false
+	nsec := t.nsec()
+	sec := t.sec()
+	if sec < 0 {
+		// Operate on absolute value.
+		neg = true
+		sec = -sec
+		nsec = -nsec
+		if nsec < 0 {
+			nsec += 1e9
+			sec-- // sec >= 1 before the -- so safe
+		}
+	}
+
+	switch {
+	// Special case: 2d divides 1 second.
+	case d < Second && Second%(d+d) == 0:
+		qmod2 = int(nsec/int32(d)) & 1
+		r = Duration(nsec % int32(d))
+
+	// Special case: d is a multiple of 1 second.
+	case d%Second == 0:
+		d1 := int64(d / Second)
+		qmod2 = int(sec/d1) & 1
+		r = Duration(sec%d1)*Second + Duration(nsec)
+
+	// General case.
+	// This could be faster if more cleverness were applied,
+	// but it's really only here to avoid special case restrictions in the API.
+	// No one will care about these cases.
+	default:
+		// Compute nanoseconds as 128-bit number.
+		sec := uint64(sec)
+		tmp := (sec >> 32) * 1e9
+		u1 := tmp >> 32
+		u0 := tmp << 32
+		tmp = (sec & 0xFFFFFFFF) * 1e9
+		u0x, u0 := u0, u0+tmp
+		if u0 < u0x {
+			u1++
+		}
+		u0x, u0 = u0, u0+uint64(nsec)
+		if u0 < u0x {
+			u1++
+		}
+
+		// Compute remainder by subtracting r<<k for decreasing k.
+		// Quotient parity is whether we subtract on last round.
+		d1 := uint64(d)
+		for d1>>63 != 1 {
+			d1 <<= 1
+		}
+		d0 := uint64(0)
+		for {
+			qmod2 = 0
+			if u1 > d1 || u1 == d1 && u0 >= d0 {
+				// subtract
+				qmod2 = 1
+				u0x, u0 = u0, u0-d0
+				if u0 > u0x {
+					u1--
+				}
+				u1 -= d1
+			}
+			if d1 == 0 && d0 == uint64(d) {
+				break
+			}
+			d0 >>= 1
+			d0 |= (d1 & 1) << 63
+			d1 >>= 1
+		}
+		r = Duration(u0)
+	}
+
+	if neg && r != 0 {
+		// If input was negative and not an exact multiple of d, we computed q, r such that
+		//	q*d + r = -t
+		// But the right answers are given by -(q-1), d-r:
+		//	q*d + r = -t
+		//	-q*d - r = t
+		//	-(q-1)*d + (d - r) = t
+		qmod2 ^= 1
+		r = d - r
+	}
+	return
+}
diff --git a/contrib/go/_std_1.19/src/time/zoneinfo.go b/contrib/go/_std_1.19/src/time/zoneinfo.go
new file mode 100644
index 0000000000..b3313583d8
--- /dev/null
+++ b/contrib/go/_std_1.19/src/time/zoneinfo.go
@@ -0,0 +1,687 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package time
+
+import (
+	"errors"
+	"sync"
+	"syscall"
+)
+
+//go:generate env ZONEINFO=$GOROOT/lib/time/zoneinfo.zip go run genzabbrs.go -output zoneinfo_abbrs_windows.go
+
+// A Location maps time instants to the zone in use at that time.
+// Typically, the Location represents the collection of time offsets
+// in use in a geographical area. For many Locations the time offset varies
+// depending on whether daylight savings time is in use at the time instant.
+type Location struct {
+	name string
+	zone []zone
+	tx   []zoneTrans
+
+	// The tzdata information can be followed by a string that describes
+	// how to handle DST transitions not recorded in zoneTrans.
+	// The format is the TZ environment variable without a colon; see
+	// https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap08.html.
+	// Example string, for America/Los_Angeles: PST8PDT,M3.2.0,M11.1.0
+	extend string
+
+	// Most lookups will be for the current time.
+	// To avoid the binary search through tx, keep a
+	// static one-element cache that gives the correct
+	// zone for the time when the Location was created.
+	// if cacheStart <= t < cacheEnd,
+	// lookup can return cacheZone.
+	// The units for cacheStart and cacheEnd are seconds
+	// since January 1, 1970 UTC, to match the argument
+	// to lookup.
+	cacheStart int64
+	cacheEnd   int64
+	cacheZone  *zone
+}
+
+// A zone represents a single time zone such as CET.
+type zone struct {
+	name   string // abbreviated name, "CET"
+	offset int    // seconds east of UTC
+	isDST  bool   // is this zone Daylight Savings Time?
+}
+
+// A zoneTrans represents a single time zone transition.
+type zoneTrans struct {
+	when         int64 // transition time, in seconds since 1970 GMT
+	index        uint8 // the index of the zone that goes into effect at that time
+	isstd, isutc bool  // ignored - no idea what these mean
+}
+
+// alpha and omega are the beginning and end of time for zone
+// transitions.
+const (
+	alpha = -1 << 63  // math.MinInt64
+	omega = 1<<63 - 1 // math.MaxInt64
+)
+
+// UTC represents Universal Coordinated Time (UTC).
+var UTC *Location = &utcLoc
+
+// utcLoc is separate so that get can refer to &utcLoc
+// and ensure that it never returns a nil *Location,
+// even if a badly behaved client has changed UTC.
+var utcLoc = Location{name: "UTC"}
+
+// Local represents the system's local time zone.
+// On Unix systems, Local consults the TZ environment
+// variable to find the time zone to use. No TZ means
+// use the system default /etc/localtime.
+// TZ="" means use UTC.
+// TZ="foo" means use file foo in the system timezone directory.
+var Local *Location = &localLoc
+
+// localLoc is separate so that initLocal can initialize
+// it even if a client has changed Local.
+var localLoc Location
+var localOnce sync.Once
+
+func (l *Location) get() *Location {
+	if l == nil {
+		return &utcLoc
+	}
+	if l == &localLoc {
+		localOnce.Do(initLocal)
+	}
+	return l
+}
+
+// String returns a descriptive name for the time zone information,
+// corresponding to the name argument to LoadLocation or FixedZone.
+func (l *Location) String() string {
+	return l.get().name
+}
+
+// FixedZone returns a Location that always uses
+// the given zone name and offset (seconds east of UTC).
+func FixedZone(name string, offset int) *Location {
+	l := &Location{
+		name:       name,
+		zone:       []zone{{name, offset, false}},
+		tx:         []zoneTrans{{alpha, 0, false, false}},
+		cacheStart: alpha,
+		cacheEnd:   omega,
+	}
+	l.cacheZone = &l.zone[0]
+	return l
+}
+
+// lookup returns information about the time zone in use at an
+// instant in time expressed as seconds since January 1, 1970 00:00:00 UTC.
+//
+// The returned information gives the name of the zone (such as "CET"),
+// the start and end times bracketing sec when that zone is in effect,
+// the offset in seconds east of UTC (such as -5*60*60), and whether
+// the daylight savings is being observed at that time.
+func (l *Location) lookup(sec int64) (name string, offset int, start, end int64, isDST bool) {
+	l = l.get()
+
+	if len(l.zone) == 0 {
+		name = "UTC"
+		offset = 0
+		start = alpha
+		end = omega
+		isDST = false
+		return
+	}
+
+	if zone := l.cacheZone; zone != nil && l.cacheStart <= sec && sec < l.cacheEnd {
+		name = zone.name
+		offset = zone.offset
+		start = l.cacheStart
+		end = l.cacheEnd
+		isDST = zone.isDST
+		return
+	}
+
+	if len(l.tx) == 0 || sec < l.tx[0].when {
+		zone := &l.zone[l.lookupFirstZone()]
+		name = zone.name
+		offset = zone.offset
+		start = alpha
+		if len(l.tx) > 0 {
+			end = l.tx[0].when
+		} else {
+			end = omega
+		}
+		isDST = zone.isDST
+		return
+	}
+
+	// Binary search for entry with largest time <= sec.
+	// Not using sort.Search to avoid dependencies.
+	tx := l.tx
+	end = omega
+	lo := 0
+	hi := len(tx)
+	for hi-lo > 1 {
+		m := lo + (hi-lo)/2
+		lim := tx[m].when
+		if sec < lim {
+			end = lim
+			hi = m
+		} else {
+			lo = m
+		}
+	}
+	zone := &l.zone[tx[lo].index]
+	name = zone.name
+	offset = zone.offset
+	start = tx[lo].when
+	// end = maintained during the search
+	isDST = zone.isDST
+
+	// If we're at the end of the known zone transitions,
+	// try the extend string.
+	if lo == len(tx)-1 && l.extend != "" {
+		if ename, eoffset, estart, eend, eisDST, ok := tzset(l.extend, end, sec); ok {
+			return ename, eoffset, estart, eend, eisDST
+		}
+	}
+
+	return
+}
+
+// lookupFirstZone returns the index of the time zone to use for times
+// before the first transition time, or when there are no transition
+// times.
+//
+// The reference implementation in localtime.c from
+// https://www.iana.org/time-zones/repository/releases/tzcode2013g.tar.gz
+// implements the following algorithm for these cases:
+//  1. If the first zone is unused by the transitions, use it.
+//  2. Otherwise, if there are transition times, and the first
+//     transition is to a zone in daylight time, find the first
+//     non-daylight-time zone before and closest to the first transition
+//     zone.
+//  3. Otherwise, use the first zone that is not daylight time, if
+//     there is one.
+//  4. Otherwise, use the first zone.
+func (l *Location) lookupFirstZone() int {
+	// Case 1.
+	if !l.firstZoneUsed() {
+		return 0
+	}
+
+	// Case 2.
+	if len(l.tx) > 0 && l.zone[l.tx[0].index].isDST {
+		for zi := int(l.tx[0].index) - 1; zi >= 0; zi-- {
+			if !l.zone[zi].isDST {
+				return zi
+			}
+		}
+	}
+
+	// Case 3.
+	for zi := range l.zone {
+		if !l.zone[zi].isDST {
+			return zi
+		}
+	}
+
+	// Case 4.
+	return 0
+}
+
+// firstZoneUsed reports whether the first zone is used by some
+// transition.
+func (l *Location) firstZoneUsed() bool {
+	for _, tx := range l.tx {
+		if tx.index == 0 {
+			return true
+		}
+	}
+	return false
+}
+
+// tzset takes a timezone string like the one found in the TZ environment
+// variable, the end of the last time zone transition expressed as seconds
+// since January 1, 1970 00:00:00 UTC, and a time expressed the same way.
+// We call this a tzset string since in C the function tzset reads TZ.
+// The return values are as for lookup, plus ok which reports whether the
+// parse succeeded.
+func tzset(s string, initEnd, sec int64) (name string, offset int, start, end int64, isDST, ok bool) {
+	var (
+		stdName, dstName     string
+		stdOffset, dstOffset int
+	)
+
+	stdName, s, ok = tzsetName(s)
+	if ok {
+		stdOffset, s, ok = tzsetOffset(s)
+	}
+	if !ok {
+		return "", 0, 0, 0, false, false
+	}
+
+	// The numbers in the tzset string are added to local time to get UTC,
+	// but our offsets are added to UTC to get local time,
+	// so we negate the number we see here.
+	stdOffset = -stdOffset
+
+	if len(s) == 0 || s[0] == ',' {
+		// No daylight savings time.
+		return stdName, stdOffset, initEnd, omega, false, true
+	}
+
+	dstName, s, ok = tzsetName(s)
+	if ok {
+		if len(s) == 0 || s[0] == ',' {
+			dstOffset = stdOffset + secondsPerHour
+		} else {
+			dstOffset, s, ok = tzsetOffset(s)
+			dstOffset = -dstOffset // as with stdOffset, above
+		}
+	}
+	if !ok {
+		return "", 0, 0, 0, false, false
+	}
+
+	if len(s) == 0 {
+		// Default DST rules per tzcode.
+		s = ",M3.2.0,M11.1.0"
+	}
+	// The TZ definition does not mention ';' here but tzcode accepts it.
+	if s[0] != ',' && s[0] != ';' {
+		return "", 0, 0, 0, false, false
+	}
+	s = s[1:]
+
+	var startRule, endRule rule
+	startRule, s, ok = tzsetRule(s)
+	if !ok || len(s) == 0 || s[0] != ',' {
+		return "", 0, 0, 0, false, false
+	}
+	s = s[1:]
+	endRule, s, ok = tzsetRule(s)
+	if !ok || len(s) > 0 {
+		return "", 0, 0, 0, false, false
+	}
+
+	year, _, _, yday := absDate(uint64(sec+unixToInternal+internalToAbsolute), false)
+
+	ysec := int64(yday*secondsPerDay) + sec%secondsPerDay
+
+	// Compute start of year in seconds since Unix epoch.
+	d := daysSinceEpoch(year)
+	abs := int64(d * secondsPerDay)
+	abs += absoluteToInternal + internalToUnix
+
+	startSec := int64(tzruleTime(year, startRule, stdOffset))
+	endSec := int64(tzruleTime(year, endRule, dstOffset))
+	dstIsDST, stdIsDST := true, false
+	// Note: this is a flipping of "DST" and "STD" while retaining the labels
+	// This happens in southern hemispheres. The labelling here thus is a little
+	// inconsistent with the goal.
+	if endSec < startSec {
+		startSec, endSec = endSec, startSec
+		stdName, dstName = dstName, stdName
+		stdOffset, dstOffset = dstOffset, stdOffset
+		stdIsDST, dstIsDST = dstIsDST, stdIsDST
+	}
+
+	// The start and end values that we return are accurate
+	// close to a daylight savings transition, but are otherwise
+	// just the start and end of the year. That suffices for
+	// the only caller that cares, which is Date.
+	if ysec < startSec {
+		return stdName, stdOffset, abs, startSec + abs, stdIsDST, true
+	} else if ysec >= endSec {
+		return stdName, stdOffset, endSec + abs, abs + 365*secondsPerDay, stdIsDST, true
+	} else {
+		return dstName, dstOffset, startSec + abs, endSec + abs, dstIsDST, true
+	}
+}
+
+// tzsetName returns the timezone name at the start of the tzset string s,
+// and the remainder of s, and reports whether the parsing is OK.
+func tzsetName(s string) (string, string, bool) {
+	if len(s) == 0 {
+		return "", "", false
+	}
+	if s[0] != '<' {
+		for i, r := range s {
+			switch r {
+			case '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', ',', '-', '+':
+				if i < 3 {
+					return "", "", false
+				}
+				return s[:i], s[i:], true
+			}
+		}
+		if len(s) < 3 {
+			return "", "", false
+		}
+		return s, "", true
+	} else {
+		for i, r := range s {
+			if r == '>' {
+				return s[1:i], s[i+1:], true
+			}
+		}
+		return "", "", false
+	}
+}
+
+// tzsetOffset returns the timezone offset at the start of the tzset string s,
+// and the remainder of s, and reports whether the parsing is OK.
+// The timezone offset is returned as a number of seconds.
+func tzsetOffset(s string) (offset int, rest string, ok bool) {
+	if len(s) == 0 {
+		return 0, "", false
+	}
+	neg := false
+	if s[0] == '+' {
+		s = s[1:]
+	} else if s[0] == '-' {
+		s = s[1:]
+		neg = true
+	}
+
+	// The tzdata code permits values up to 24 * 7 here,
+	// although POSIX does not.
+	var hours int
+	hours, s, ok = tzsetNum(s, 0, 24*7)
+	if !ok {
+		return 0, "", false
+	}
+	off := hours * secondsPerHour
+	if len(s) == 0 || s[0] != ':' {
+		if neg {
+			off = -off
+		}
+		return off, s, true
+	}
+
+	var mins int
+	mins, s, ok = tzsetNum(s[1:], 0, 59)
+	if !ok {
+		return 0, "", false
+	}
+	off += mins * secondsPerMinute
+	if len(s) == 0 || s[0] != ':' {
+		if neg {
+			off = -off
+		}
+		return off, s, true
+	}
+
+	var secs int
+	secs, s, ok = tzsetNum(s[1:], 0, 59)
+	if !ok {
+		return 0, "", false
+	}
+	off += secs
+
+	if neg {
+		off = -off
+	}
+	return off, s, true
+}
+
+// ruleKind is the kinds of rules that can be seen in a tzset string.
+type ruleKind int
+
+const (
+	ruleJulian ruleKind = iota
+	ruleDOY
+	ruleMonthWeekDay
+)
+
+// rule is a rule read from a tzset string.
+type rule struct {
+	kind ruleKind
+	day  int
+	week int
+	mon  int
+	time int // transition time
+}
+
+// tzsetRule parses a rule from a tzset string.
+// It returns the rule, and the remainder of the string, and reports success.
+func tzsetRule(s string) (rule, string, bool) {
+	var r rule
+	if len(s) == 0 {
+		return rule{}, "", false
+	}
+	ok := false
+	if s[0] == 'J' {
+		var jday int
+		jday, s, ok = tzsetNum(s[1:], 1, 365)
+		if !ok {
+			return rule{}, "", false
+		}
+		r.kind = ruleJulian
+		r.day = jday
+	} else if s[0] == 'M' {
+		var mon int
+		mon, s, ok = tzsetNum(s[1:], 1, 12)
+		if !ok || len(s) == 0 || s[0] != '.' {
+			return rule{}, "", false
+
+		}
+		var week int
+		week, s, ok = tzsetNum(s[1:], 1, 5)
+		if !ok || len(s) == 0 || s[0] != '.' {
+			return rule{}, "", false
+		}
+		var day int
+		day, s, ok = tzsetNum(s[1:], 0, 6)
+		if !ok {
+			return rule{}, "", false
+		}
+		r.kind = ruleMonthWeekDay
+		r.day = day
+		r.week = week
+		r.mon = mon
+	} else {
+		var day int
+		day, s, ok = tzsetNum(s, 0, 365)
+		if !ok {
+			return rule{}, "", false
+		}
+		r.kind = ruleDOY
+		r.day = day
+	}
+
+	if len(s) == 0 || s[0] != '/' {
+		r.time = 2 * secondsPerHour // 2am is the default
+		return r, s, true
+	}
+
+	offset, s, ok := tzsetOffset(s[1:])
+	if !ok {
+		return rule{}, "", false
+	}
+	r.time = offset
+
+	return r, s, true
+}
+
+// tzsetNum parses a number from a tzset string.
+// It returns the number, and the remainder of the string, and reports success.
+// The number must be between min and max.
+func tzsetNum(s string, min, max int) (num int, rest string, ok bool) {
+	if len(s) == 0 {
+		return 0, "", false
+	}
+	num = 0
+	for i, r := range s {
+		if r < '0' || r > '9' {
+			if i == 0 || num < min {
+				return 0, "", false
+			}
+			return num, s[i:], true
+		}
+		num *= 10
+		num += int(r) - '0'
+		if num > max {
+			return 0, "", false
+		}
+	}
+	if num < min {
+		return 0, "", false
+	}
+	return num, "", true
+}
+
+// tzruleTime takes a year, a rule, and a timezone offset,
+// and returns the number of seconds since the start of the year
+// that the rule takes effect.
+func tzruleTime(year int, r rule, off int) int {
+	var s int
+	switch r.kind {
+	case ruleJulian:
+		s = (r.day - 1) * secondsPerDay
+		if isLeap(year) && r.day >= 60 {
+			s += secondsPerDay
+		}
+	case ruleDOY:
+		s = r.day * secondsPerDay
+	case ruleMonthWeekDay:
+		// Zeller's Congruence.
+		m1 := (r.mon+9)%12 + 1
+		yy0 := year
+		if r.mon <= 2 {
+			yy0--
+		}
+		yy1 := yy0 / 100
+		yy2 := yy0 % 100
+		dow := ((26*m1-2)/10 + 1 + yy2 + yy2/4 + yy1/4 - 2*yy1) % 7
+		if dow < 0 {
+			dow += 7
+		}
+		// Now dow is the day-of-week of the first day of r.mon.
+		// Get the day-of-month of the first "dow" day.
+		d := r.day - dow
+		if d < 0 {
+			d += 7
+		}
+		for i := 1; i < r.week; i++ {
+			if d+7 >= daysIn(Month(r.mon), year) {
+				break
+			}
+			d += 7
+		}
+		d += int(daysBefore[r.mon-1])
+		if isLeap(year) && r.mon > 2 {
+			d++
+		}
+		s = d * secondsPerDay
+	}
+
+	return s + r.time - off
+}
+
+// lookupName returns information about the time zone with
+// the given name (such as "EST") at the given pseudo-Unix time
+// (what the given time of day would be in UTC).
+func (l *Location) lookupName(name string, unix int64) (offset int, ok bool) {
+	l = l.get()
+
+	// First try for a zone with the right name that was actually
+	// in effect at the given time. (In Sydney, Australia, both standard
+	// and daylight-savings time are abbreviated "EST". Using the
+	// offset helps us pick the right one for the given time.
+	// It's not perfect: during the backward transition we might pick
+	// either one.)
+	for i := range l.zone {
+		zone := &l.zone[i]
+		if zone.name == name {
+			nam, offset, _, _, _ := l.lookup(unix - int64(zone.offset))
+			if nam == zone.name {
+				return offset, true
+			}
+		}
+	}
+
+	// Otherwise fall back to an ordinary name match.
+	for i := range l.zone {
+		zone := &l.zone[i]
+		if zone.name == name {
+			return zone.offset, true
+		}
+	}
+
+	// Otherwise, give up.
+	return
+}
+
+// NOTE(rsc): Eventually we will need to accept the POSIX TZ environment
+// syntax too, but I don't feel like implementing it today.
+
+var errLocation = errors.New("time: invalid location name")
+
+var zoneinfo *string
+var zoneinfoOnce sync.Once
+
+// LoadLocation returns the Location with the given name.
+//
+// If the name is "" or "UTC", LoadLocation returns UTC.
+// If the name is "Local", LoadLocation returns Local.
+//
+// Otherwise, the name is taken to be a location name corresponding to a file
+// in the IANA Time Zone database, such as "America/New_York".
+//
+// LoadLocation looks for the IANA Time Zone database in the following
+// locations in order:
+//
+// - the directory or uncompressed zip file named by the ZONEINFO environment variable
+// - on a Unix system, the system standard installation location
+// - $GOROOT/lib/time/zoneinfo.zip
+// - the time/tzdata package, if it was imported
+func LoadLocation(name string) (*Location, error) {
+	if name == "" || name == "UTC" {
+		return UTC, nil
+	}
+	if name == "Local" {
+		return Local, nil
+	}
+	if containsDotDot(name) || name[0] == '/' || name[0] == '\\' {
+		// No valid IANA Time Zone name contains a single dot,
+		// much less dot dot. Likewise, none begin with a slash.
+		return nil, errLocation
+	}
+	zoneinfoOnce.Do(func() {
+		env, _ := syscall.Getenv("ZONEINFO")
+		zoneinfo = &env
+	})
+	var firstErr error
+	if *zoneinfo != "" {
+		if zoneData, err := loadTzinfoFromDirOrZip(*zoneinfo, name); err == nil {
+			if z, err := LoadLocationFromTZData(name, zoneData); err == nil {
+				return z, nil
+			}
+			firstErr = err
+		} else if err != syscall.ENOENT {
+			firstErr = err
+		}
+	}
+	if z, err := loadLocation(name, platformZoneSources); err == nil {
+		return z, nil
+	} else if firstErr == nil {
+		firstErr = err
+	}
+	return nil, firstErr
+}
+
+// containsDotDot reports whether s contains "..".
+func containsDotDot(s string) bool {
+	if len(s) < 2 {
+		return false
+	}
+	for i := 0; i < len(s)-1; i++ {
+		if s[i] == '.' && s[i+1] == '.' {
+			return true
+		}
+	}
+	return false
+}
diff --git a/contrib/go/_std_1.19/src/time/zoneinfo_goroot.go b/contrib/go/_std_1.19/src/time/zoneinfo_goroot.go
new file mode 100644
index 0000000000..92bdcf4afe
--- /dev/null
+++ b/contrib/go/_std_1.19/src/time/zoneinfo_goroot.go
@@ -0,0 +1,14 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !ios && !android
+
+package time
+
+func gorootZoneSource(goroot string) (string, bool) {
+	if goroot == "" {
+		return "", false
+	}
+	return goroot + "/lib/time/zoneinfo.zip", true
+}
diff --git a/contrib/go/_std_1.19/src/time/zoneinfo_read.go b/contrib/go/_std_1.19/src/time/zoneinfo_read.go
new file mode 100644
index 0000000000..90814ad36a
--- /dev/null
+++ b/contrib/go/_std_1.19/src/time/zoneinfo_read.go
@@ -0,0 +1,597 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Parse "zoneinfo" time zone file.
+// This is a fairly standard file format used on OS X, Linux, BSD, Sun, and others.
+// See tzfile(5), https://en.wikipedia.org/wiki/Zoneinfo,
+// and ftp://munnari.oz.au/pub/oldtz/
+
+package time
+
+import (
+	"errors"
+	"runtime"
+	"syscall"
+)
+
+// registerLoadFromEmbeddedTZData is called by the time/tzdata package,
+// if it is imported.
+func registerLoadFromEmbeddedTZData(f func(string) (string, error)) {
+	loadFromEmbeddedTZData = f
+}
+
+// loadFromEmbeddedTZData is used to load a specific tzdata file
+// from tzdata information embedded in the binary itself.
+// This is set when the time/tzdata package is imported,
+// via registerLoadFromEmbeddedTzdata.
+var loadFromEmbeddedTZData func(zipname string) (string, error)
+
+// maxFileSize is the max permitted size of files read by readFile.
+// As reference, the zoneinfo.zip distributed by Go is ~350 KB,
+// so 10MB is overkill.
+const maxFileSize = 10 << 20
+
+type fileSizeError string
+
+func (f fileSizeError) Error() string {
+	return "time: file " + string(f) + " is too large"
+}
+
+// Copies of io.Seek* constants to avoid importing "io":
+const (
+	seekStart   = 0
+	seekCurrent = 1
+	seekEnd     = 2
+)
+
+// Simple I/O interface to binary blob of data.
+type dataIO struct {
+	p     []byte
+	error bool
+}
+
+func (d *dataIO) read(n int) []byte {
+	if len(d.p) < n {
+		d.p = nil
+		d.error = true
+		return nil
+	}
+	p := d.p[0:n]
+	d.p = d.p[n:]
+	return p
+}
+
+func (d *dataIO) big4() (n uint32, ok bool) {
+	p := d.read(4)
+	if len(p) < 4 {
+		d.error = true
+		return 0, false
+	}
+	return uint32(p[3]) | uint32(p[2])<<8 | uint32(p[1])<<16 | uint32(p[0])<<24, true
+}
+
+func (d *dataIO) big8() (n uint64, ok bool) {
+	n1, ok1 := d.big4()
+	n2, ok2 := d.big4()
+	if !ok1 || !ok2 {
+		d.error = true
+		return 0, false
+	}
+	return (uint64(n1) << 32) | uint64(n2), true
+}
+
+func (d *dataIO) byte() (n byte, ok bool) {
+	p := d.read(1)
+	if len(p) < 1 {
+		d.error = true
+		return 0, false
+	}
+	return p[0], true
+}
+
+// read returns the read of the data in the buffer.
+func (d *dataIO) rest() []byte {
+	r := d.p
+	d.p = nil
+	return r
+}
+
+// Make a string by stopping at the first NUL
+func byteString(p []byte) string {
+	for i := 0; i < len(p); i++ {
+		if p[i] == 0 {
+			return string(p[0:i])
+		}
+	}
+	return string(p)
+}
+
+var badData = errors.New("malformed time zone information")
+
+// LoadLocationFromTZData returns a Location with the given name
+// initialized from the IANA Time Zone database-formatted data.
+// The data should be in the format of a standard IANA time zone file
+// (for example, the content of /etc/localtime on Unix systems).
+func LoadLocationFromTZData(name string, data []byte) (*Location, error) {
+	d := dataIO{data, false}
+
+	// 4-byte magic "TZif"
+	if magic := d.read(4); string(magic) != "TZif" {
+		return nil, badData
+	}
+
+	// 1-byte version, then 15 bytes of padding
+	var version int
+	var p []byte
+	if p = d.read(16); len(p) != 16 {
+		return nil, badData
+	} else {
+		switch p[0] {
+		case 0:
+			version = 1
+		case '2':
+			version = 2
+		case '3':
+			version = 3
+		default:
+			return nil, badData
+		}
+	}
+
+	// six big-endian 32-bit integers:
+	//	number of UTC/local indicators
+	//	number of standard/wall indicators
+	//	number of leap seconds
+	//	number of transition times
+	//	number of local time zones
+	//	number of characters of time zone abbrev strings
+	const (
+		NUTCLocal = iota
+		NStdWall
+		NLeap
+		NTime
+		NZone
+		NChar
+	)
+	var n [6]int
+	for i := 0; i < 6; i++ {
+		nn, ok := d.big4()
+		if !ok {
+			return nil, badData
+		}
+		if uint32(int(nn)) != nn {
+			return nil, badData
+		}
+		n[i] = int(nn)
+	}
+
+	// If we have version 2 or 3, then the data is first written out
+	// in a 32-bit format, then written out again in a 64-bit format.
+	// Skip the 32-bit format and read the 64-bit one, as it can
+	// describe a broader range of dates.
+
+	is64 := false
+	if version > 1 {
+		// Skip the 32-bit data.
+		skip := n[NTime]*4 +
+			n[NTime] +
+			n[NZone]*6 +
+			n[NChar] +
+			n[NLeap]*8 +
+			n[NStdWall] +
+			n[NUTCLocal]
+		// Skip the version 2 header that we just read.
+		skip += 4 + 16
+		d.read(skip)
+
+		is64 = true
+
+		// Read the counts again, they can differ.
+		for i := 0; i < 6; i++ {
+			nn, ok := d.big4()
+			if !ok {
+				return nil, badData
+			}
+			if uint32(int(nn)) != nn {
+				return nil, badData
+			}
+			n[i] = int(nn)
+		}
+	}
+
+	size := 4
+	if is64 {
+		size = 8
+	}
+
+	// Transition times.
+	txtimes := dataIO{d.read(n[NTime] * size), false}
+
+	// Time zone indices for transition times.
+	txzones := d.read(n[NTime])
+
+	// Zone info structures
+	zonedata := dataIO{d.read(n[NZone] * 6), false}
+
+	// Time zone abbreviations.
+	abbrev := d.read(n[NChar])
+
+	// Leap-second time pairs
+	d.read(n[NLeap] * (size + 4))
+
+	// Whether tx times associated with local time types
+	// are specified as standard time or wall time.
+	isstd := d.read(n[NStdWall])
+
+	// Whether tx times associated with local time types
+	// are specified as UTC or local time.
+	isutc := d.read(n[NUTCLocal])
+
+	if d.error { // ran out of data
+		return nil, badData
+	}
+
+	var extend string
+	rest := d.rest()
+	if len(rest) > 2 && rest[0] == '\n' && rest[len(rest)-1] == '\n' {
+		extend = string(rest[1 : len(rest)-1])
+	}
+
+	// Now we can build up a useful data structure.
+	// First the zone information.
+	//	utcoff[4] isdst[1] nameindex[1]
+	nzone := n[NZone]
+	if nzone == 0 {
+		// Reject tzdata files with no zones. There's nothing useful in them.
+		// This also avoids a panic later when we add and then use a fake transition (golang.org/issue/29437).
+		return nil, badData
+	}
+	zones := make([]zone, nzone)
+	for i := range zones {
+		var ok bool
+		var n uint32
+		if n, ok = zonedata.big4(); !ok {
+			return nil, badData
+		}
+		if uint32(int(n)) != n {
+			return nil, badData
+		}
+		zones[i].offset = int(int32(n))
+		var b byte
+		if b, ok = zonedata.byte(); !ok {
+			return nil, badData
+		}
+		zones[i].isDST = b != 0
+		if b, ok = zonedata.byte(); !ok || int(b) >= len(abbrev) {
+			return nil, badData
+		}
+		zones[i].name = byteString(abbrev[b:])
+		if runtime.GOOS == "aix" && len(name) > 8 && (name[:8] == "Etc/GMT+" || name[:8] == "Etc/GMT-") {
+			// There is a bug with AIX 7.2 TL 0 with files in Etc,
+			// GMT+1 will return GMT-1 instead of GMT+1 or -01.
+			if name != "Etc/GMT+0" {
+				// GMT+0 is OK
+				zones[i].name = name[4:]
+			}
+		}
+	}
+
+	// Now the transition time info.
+	tx := make([]zoneTrans, n[NTime])
+	for i := range tx {
+		var n int64
+		if !is64 {
+			if n4, ok := txtimes.big4(); !ok {
+				return nil, badData
+			} else {
+				n = int64(int32(n4))
+			}
+		} else {
+			if n8, ok := txtimes.big8(); !ok {
+				return nil, badData
+			} else {
+				n = int64(n8)
+			}
+		}
+		tx[i].when = n
+		if int(txzones[i]) >= len(zones) {
+			return nil, badData
+		}
+		tx[i].index = txzones[i]
+		if i < len(isstd) {
+			tx[i].isstd = isstd[i] != 0
+		}
+		if i < len(isutc) {
+			tx[i].isutc = isutc[i] != 0
+		}
+	}
+
+	if len(tx) == 0 {
+		// Build fake transition to cover all time.
+		// This happens in fixed locations like "Etc/GMT0".
+		tx = append(tx, zoneTrans{when: alpha, index: 0})
+	}
+
+	// Committed to succeed.
+	l := &Location{zone: zones, tx: tx, name: name, extend: extend}
+
+	// Fill in the cache with information about right now,
+	// since that will be the most common lookup.
+	sec, _, _ := now()
+	for i := range tx {
+		if tx[i].when <= sec && (i+1 == len(tx) || sec < tx[i+1].when) {
+			l.cacheStart = tx[i].when
+			l.cacheEnd = omega
+			l.cacheZone = &l.zone[tx[i].index]
+			if i+1 < len(tx) {
+				l.cacheEnd = tx[i+1].when
+			} else if l.extend != "" {
+				// If we're at the end of the known zone transitions,
+				// try the extend string.
+				if name, offset, estart, eend, isDST, ok := tzset(l.extend, l.cacheEnd, sec); ok {
+					l.cacheStart = estart
+					l.cacheEnd = eend
+					// Find the zone that is returned by tzset to avoid allocation if possible.
+					if zoneIdx := findZone(l.zone, name, offset, isDST); zoneIdx != -1 {
+						l.cacheZone = &l.zone[zoneIdx]
+					} else {
+						l.cacheZone = &zone{
+							name:   name,
+							offset: offset,
+							isDST:  isDST,
+						}
+					}
+				}
+			}
+			break
+		}
+	}
+
+	return l, nil
+}
+
+func findZone(zones []zone, name string, offset int, isDST bool) int {
+	for i, z := range zones {
+		if z.name == name && z.offset == offset && z.isDST == isDST {
+			return i
+		}
+	}
+	return -1
+}
+
+// loadTzinfoFromDirOrZip returns the contents of the file with the given name
+// in dir. dir can either be an uncompressed zip file, or a directory.
+func loadTzinfoFromDirOrZip(dir, name string) ([]byte, error) {
+	if len(dir) > 4 && dir[len(dir)-4:] == ".zip" {
+		return loadTzinfoFromZip(dir, name)
+	}
+	if dir != "" {
+		name = dir + "/" + name
+	}
+	return readFile(name)
+}
+
+// There are 500+ zoneinfo files. Rather than distribute them all
+// individually, we ship them in an uncompressed zip file.
+// Used this way, the zip file format serves as a commonly readable
+// container for the individual small files. We choose zip over tar
+// because zip files have a contiguous table of contents, making
+// individual file lookups faster, and because the per-file overhead
+// in a zip file is considerably less than tar's 512 bytes.
+
+// get4 returns the little-endian 32-bit value in b.
+func get4(b []byte) int {
+	if len(b) < 4 {
+		return 0
+	}
+	return int(b[0]) | int(b[1])<<8 | int(b[2])<<16 | int(b[3])<<24
+}
+
+// get2 returns the little-endian 16-bit value in b.
+func get2(b []byte) int {
+	if len(b) < 2 {
+		return 0
+	}
+	return int(b[0]) | int(b[1])<<8
+}
+
+// loadTzinfoFromZip returns the contents of the file with the given name
+// in the given uncompressed zip file.
+func loadTzinfoFromZip(zipfile, name string) ([]byte, error) {
+	fd, err := open(zipfile)
+	if err != nil {
+		return nil, err
+	}
+	defer closefd(fd)
+
+	const (
+		zecheader = 0x06054b50
+		zcheader  = 0x02014b50
+		ztailsize = 22
+
+		zheadersize = 30
+		zheader     = 0x04034b50
+	)
+
+	buf := make([]byte, ztailsize)
+	if err := preadn(fd, buf, -ztailsize); err != nil || get4(buf) != zecheader {
+		return nil, errors.New("corrupt zip file " + zipfile)
+	}
+	n := get2(buf[10:])
+	size := get4(buf[12:])
+	off := get4(buf[16:])
+
+	buf = make([]byte, size)
+	if err := preadn(fd, buf, off); err != nil {
+		return nil, errors.New("corrupt zip file " + zipfile)
+	}
+
+	for i := 0; i < n; i++ {
+		// zip entry layout:
+		//	0	magic[4]
+		//	4	madevers[1]
+		//	5	madeos[1]
+		//	6	extvers[1]
+		//	7	extos[1]
+		//	8	flags[2]
+		//	10	meth[2]
+		//	12	modtime[2]
+		//	14	moddate[2]
+		//	16	crc[4]
+		//	20	csize[4]
+		//	24	uncsize[4]
+		//	28	namelen[2]
+		//	30	xlen[2]
+		//	32	fclen[2]
+		//	34	disknum[2]
+		//	36	iattr[2]
+		//	38	eattr[4]
+		//	42	off[4]
+		//	46	name[namelen]
+		//	46+namelen+xlen+fclen - next header
+		//
+		if get4(buf) != zcheader {
+			break
+		}
+		meth := get2(buf[10:])
+		size := get4(buf[24:])
+		namelen := get2(buf[28:])
+		xlen := get2(buf[30:])
+		fclen := get2(buf[32:])
+		off := get4(buf[42:])
+		zname := buf[46 : 46+namelen]
+		buf = buf[46+namelen+xlen+fclen:]
+		if string(zname) != name {
+			continue
+		}
+		if meth != 0 {
+			return nil, errors.New("unsupported compression for " + name + " in " + zipfile)
+		}
+
+		// zip per-file header layout:
+		//	0	magic[4]
+		//	4	extvers[1]
+		//	5	extos[1]
+		//	6	flags[2]
+		//	8	meth[2]
+		//	10	modtime[2]
+		//	12	moddate[2]
+		//	14	crc[4]
+		//	18	csize[4]
+		//	22	uncsize[4]
+		//	26	namelen[2]
+		//	28	xlen[2]
+		//	30	name[namelen]
+		//	30+namelen+xlen - file data
+		//
+		buf = make([]byte, zheadersize+namelen)
+		if err := preadn(fd, buf, off); err != nil ||
+			get4(buf) != zheader ||
+			get2(buf[8:]) != meth ||
+			get2(buf[26:]) != namelen ||
+			string(buf[30:30+namelen]) != name {
+			return nil, errors.New("corrupt zip file " + zipfile)
+		}
+		xlen = get2(buf[28:])
+
+		buf = make([]byte, size)
+		if err := preadn(fd, buf, off+30+namelen+xlen); err != nil {
+			return nil, errors.New("corrupt zip file " + zipfile)
+		}
+
+		return buf, nil
+	}
+
+	return nil, syscall.ENOENT
+}
+
+// loadTzinfoFromTzdata returns the time zone information of the time zone
+// with the given name, from a tzdata database file as they are typically
+// found on android.
+var loadTzinfoFromTzdata func(file, name string) ([]byte, error)
+
+// loadTzinfo returns the time zone information of the time zone
+// with the given name, from a given source. A source may be a
+// timezone database directory, tzdata database file or an uncompressed
+// zip file, containing the contents of such a directory.
+func loadTzinfo(name string, source string) ([]byte, error) {
+	if len(source) >= 6 && source[len(source)-6:] == "tzdata" {
+		return loadTzinfoFromTzdata(source, name)
+	}
+	return loadTzinfoFromDirOrZip(source, name)
+}
+
+// loadLocation returns the Location with the given name from one of
+// the specified sources. See loadTzinfo for a list of supported sources.
+// The first timezone data matching the given name that is successfully loaded
+// and parsed is returned as a Location.
+func loadLocation(name string, sources []string) (z *Location, firstErr error) {
+	for _, source := range sources {
+		zoneData, err := loadTzinfo(name, source)
+		if err == nil {
+			if z, err = LoadLocationFromTZData(name, zoneData); err == nil {
+				return z, nil
+			}
+		}
+		if firstErr == nil && err != syscall.ENOENT {
+			firstErr = err
+		}
+	}
+	if loadFromEmbeddedTZData != nil {
+		zoneData, err := loadFromEmbeddedTZData(name)
+		if err == nil {
+			if z, err = LoadLocationFromTZData(name, []byte(zoneData)); err == nil {
+				return z, nil
+			}
+		}
+		if firstErr == nil && err != syscall.ENOENT {
+			firstErr = err
+		}
+	}
+	if source, ok := gorootZoneSource(runtime.GOROOT()); ok {
+		zoneData, err := loadTzinfo(name, source)
+		if err == nil {
+			if z, err = LoadLocationFromTZData(name, zoneData); err == nil {
+				return z, nil
+			}
+		}
+		if firstErr == nil && err != syscall.ENOENT {
+			firstErr = err
+		}
+	}
+	if firstErr != nil {
+		return nil, firstErr
+	}
+	return nil, errors.New("unknown time zone " + name)
+}
+
+// readFile reads and returns the content of the named file.
+// It is a trivial implementation of os.ReadFile, reimplemented
+// here to avoid depending on io/ioutil or os.
+// It returns an error if name exceeds maxFileSize bytes.
+func readFile(name string) ([]byte, error) {
+	f, err := open(name)
+	if err != nil {
+		return nil, err
+	}
+	defer closefd(f)
+	var (
+		buf [4096]byte
+		ret []byte
+		n   int
+	)
+	for {
+		n, err = read(f, buf[:])
+		if n > 0 {
+			ret = append(ret, buf[:n]...)
+		}
+		if n == 0 || err != nil {
+			break
+		}
+		if len(ret) > maxFileSize {
+			return nil, fileSizeError(name)
+		}
+	}
+	return ret, err
+}
diff --git a/contrib/go/_std_1.19/src/time/zoneinfo_unix.go b/contrib/go/_std_1.19/src/time/zoneinfo_unix.go
new file mode 100644
index 0000000000..67b8beb47b
--- /dev/null
+++ b/contrib/go/_std_1.19/src/time/zoneinfo_unix.go
@@ -0,0 +1,67 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix && !ios && !android
+
+// Parse "zoneinfo" time zone file.
+// This is a fairly standard file format used on OS X, Linux, BSD, Sun, and others.
+// See tzfile(5), https://en.wikipedia.org/wiki/Zoneinfo,
+// and ftp://munnari.oz.au/pub/oldtz/
+
+package time
+
+import (
+	"syscall"
+)
+
+// Many systems use /usr/share/zoneinfo, Solaris 2 has
+// /usr/share/lib/zoneinfo, IRIX 6 has /usr/lib/locale/TZ.
+var platformZoneSources = []string{
+	"/usr/share/zoneinfo/",
+	"/usr/share/lib/zoneinfo/",
+	"/usr/lib/locale/TZ/",
+}
+
+func initLocal() {
+	// consult $TZ to find the time zone to use.
+	// no $TZ means use the system default /etc/localtime.
+	// $TZ="" means use UTC.
+	// $TZ="foo" or $TZ=":foo" if foo is an absolute path, then the file pointed
+	// by foo will be used to initialize timezone; otherwise, file
+	// /usr/share/zoneinfo/foo will be used.
+
+	tz, ok := syscall.Getenv("TZ")
+	switch {
+	case !ok:
+		z, err := loadLocation("localtime", []string{"/etc"})
+		if err == nil {
+			localLoc = *z
+			localLoc.name = "Local"
+			return
+		}
+	case tz != "":
+		if tz[0] == ':' {
+			tz = tz[1:]
+		}
+		if tz != "" && tz[0] == '/' {
+			if z, err := loadLocation(tz, []string{""}); err == nil {
+				localLoc = *z
+				if tz == "/etc/localtime" {
+					localLoc.name = "Local"
+				} else {
+					localLoc.name = tz
+				}
+				return
+			}
+		} else if tz != "" && tz != "UTC" {
+			if z, err := loadLocation(tz, platformZoneSources); err == nil {
+				localLoc = *z
+				return
+			}
+		}
+	}
+
+	// Fall back to UTC.
+	localLoc.name = "UTC"
+}
diff --git a/contrib/go/_std_1.18/src/unicode/casetables.go b/contrib/go/_std_1.19/src/unicode/casetables.go
index 29bf167e56..29bf167e56 100644
--- a/contrib/go/_std_1.18/src/unicode/casetables.go
+++ b/contrib/go/_std_1.19/src/unicode/casetables.go
diff --git a/contrib/go/_std_1.18/src/unicode/digit.go b/contrib/go/_std_1.19/src/unicode/digit.go
index 53171b3969..53171b3969 100644
--- a/contrib/go/_std_1.18/src/unicode/digit.go
+++ b/contrib/go/_std_1.19/src/unicode/digit.go
diff --git a/contrib/go/_std_1.19/src/unicode/graphic.go b/contrib/go/_std_1.19/src/unicode/graphic.go
new file mode 100644
index 0000000000..2af29778bf
--- /dev/null
+++ b/contrib/go/_std_1.19/src/unicode/graphic.go
@@ -0,0 +1,146 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package unicode
+
+// Bit masks for each code point under U+0100, for fast lookup.
+const (
+	pC     = 1 << iota // a control character.
+	pP                 // a punctuation character.
+	pN                 // a numeral.
+	pS                 // a symbolic character.
+	pZ                 // a spacing character.
+	pLu                // an upper-case letter.
+	pLl                // a lower-case letter.
+	pp                 // a printable character according to Go's definition.
+	pg     = pp | pZ   // a graphical character according to the Unicode definition.
+	pLo    = pLl | pLu // a letter that is neither upper nor lower case.
+	pLmask = pLo
+)
+
+// GraphicRanges defines the set of graphic characters according to Unicode.
+var GraphicRanges = []*RangeTable{
+	L, M, N, P, S, Zs,
+}
+
+// PrintRanges defines the set of printable characters according to Go.
+// ASCII space, U+0020, is handled separately.
+var PrintRanges = []*RangeTable{
+	L, M, N, P, S,
+}
+
+// IsGraphic reports whether the rune is defined as a Graphic by Unicode.
+// Such characters include letters, marks, numbers, punctuation, symbols, and
+// spaces, from categories L, M, N, P, S, Zs.
+func IsGraphic(r rune) bool {
+	// We convert to uint32 to avoid the extra test for negative,
+	// and in the index we convert to uint8 to avoid the range check.
+	if uint32(r) <= MaxLatin1 {
+		return properties[uint8(r)]&pg != 0
+	}
+	return In(r, GraphicRanges...)
+}
+
+// IsPrint reports whether the rune is defined as printable by Go. Such
+// characters include letters, marks, numbers, punctuation, symbols, and the
+// ASCII space character, from categories L, M, N, P, S and the ASCII space
+// character. This categorization is the same as IsGraphic except that the
+// only spacing character is ASCII space, U+0020.
+func IsPrint(r rune) bool {
+	if uint32(r) <= MaxLatin1 {
+		return properties[uint8(r)]&pp != 0
+	}
+	return In(r, PrintRanges...)
+}
+
+// IsOneOf reports whether the rune is a member of one of the ranges.
+// The function "In" provides a nicer signature and should be used in preference to IsOneOf.
+func IsOneOf(ranges []*RangeTable, r rune) bool {
+	for _, inside := range ranges {
+		if Is(inside, r) {
+			return true
+		}
+	}
+	return false
+}
+
+// In reports whether the rune is a member of one of the ranges.
+func In(r rune, ranges ...*RangeTable) bool {
+	for _, inside := range ranges {
+		if Is(inside, r) {
+			return true
+		}
+	}
+	return false
+}
+
+// IsControl reports whether the rune is a control character.
+// The C (Other) Unicode category includes more code points
+// such as surrogates; use Is(C, r) to test for them.
+func IsControl(r rune) bool {
+	if uint32(r) <= MaxLatin1 {
+		return properties[uint8(r)]&pC != 0
+	}
+	// All control characters are < MaxLatin1.
+	return false
+}
+
+// IsLetter reports whether the rune is a letter (category L).
+func IsLetter(r rune) bool {
+	if uint32(r) <= MaxLatin1 {
+		return properties[uint8(r)]&(pLmask) != 0
+	}
+	return isExcludingLatin(Letter, r)
+}
+
+// IsMark reports whether the rune is a mark character (category M).
+func IsMark(r rune) bool {
+	// There are no mark characters in Latin-1.
+	return isExcludingLatin(Mark, r)
+}
+
+// IsNumber reports whether the rune is a number (category N).
+func IsNumber(r rune) bool {
+	if uint32(r) <= MaxLatin1 {
+		return properties[uint8(r)]&pN != 0
+	}
+	return isExcludingLatin(Number, r)
+}
+
+// IsPunct reports whether the rune is a Unicode punctuation character
+// (category P).
+func IsPunct(r rune) bool {
+	if uint32(r) <= MaxLatin1 {
+		return properties[uint8(r)]&pP != 0
+	}
+	return Is(Punct, r)
+}
+
+// IsSpace reports whether the rune is a space character as defined
+// by Unicode's White Space property; in the Latin-1 space
+// this is
+//
+//	'\t', '\n', '\v', '\f', '\r', ' ', U+0085 (NEL), U+00A0 (NBSP).
+//
+// Other definitions of spacing characters are set by category
+// Z and property Pattern_White_Space.
+func IsSpace(r rune) bool {
+	// This property isn't the same as Z; special-case it.
+	if uint32(r) <= MaxLatin1 {
+		switch r {
+		case '\t', '\n', '\v', '\f', '\r', ' ', 0x85, 0xA0:
+			return true
+		}
+		return false
+	}
+	return isExcludingLatin(White_Space, r)
+}
+
+// IsSymbol reports whether the rune is a symbolic character.
+func IsSymbol(r rune) bool {
+	if uint32(r) <= MaxLatin1 {
+		return properties[uint8(r)]&pS != 0
+	}
+	return isExcludingLatin(Symbol, r)
+}
diff --git a/contrib/go/_std_1.19/src/unicode/letter.go b/contrib/go/_std_1.19/src/unicode/letter.go
new file mode 100644
index 0000000000..f3f8e52964
--- /dev/null
+++ b/contrib/go/_std_1.19/src/unicode/letter.go
@@ -0,0 +1,371 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package unicode provides data and functions to test some properties of
+// Unicode code points.
+package unicode
+
+const (
+	MaxRune         = '\U0010FFFF' // Maximum valid Unicode code point.
+	ReplacementChar = '\uFFFD'     // Represents invalid code points.
+	MaxASCII        = '\u007F'     // maximum ASCII value.
+	MaxLatin1       = '\u00FF'     // maximum Latin-1 value.
+)
+
+// RangeTable defines a set of Unicode code points by listing the ranges of
+// code points within the set. The ranges are listed in two slices
+// to save space: a slice of 16-bit ranges and a slice of 32-bit ranges.
+// The two slices must be in sorted order and non-overlapping.
+// Also, R32 should contain only values >= 0x10000 (1<<16).
+type RangeTable struct {
+	R16         []Range16
+	R32         []Range32
+	LatinOffset int // number of entries in R16 with Hi <= MaxLatin1
+}
+
+// Range16 represents of a range of 16-bit Unicode code points. The range runs from Lo to Hi
+// inclusive and has the specified stride.
+type Range16 struct {
+	Lo     uint16
+	Hi     uint16
+	Stride uint16
+}
+
+// Range32 represents of a range of Unicode code points and is used when one or
+// more of the values will not fit in 16 bits. The range runs from Lo to Hi
+// inclusive and has the specified stride. Lo and Hi must always be >= 1<<16.
+type Range32 struct {
+	Lo     uint32
+	Hi     uint32
+	Stride uint32
+}
+
+// CaseRange represents a range of Unicode code points for simple (one
+// code point to one code point) case conversion.
+// The range runs from Lo to Hi inclusive, with a fixed stride of 1. Deltas
+// are the number to add to the code point to reach the code point for a
+// different case for that character. They may be negative. If zero, it
+// means the character is in the corresponding case. There is a special
+// case representing sequences of alternating corresponding Upper and Lower
+// pairs. It appears with a fixed Delta of
+//
+//	{UpperLower, UpperLower, UpperLower}
+//
+// The constant UpperLower has an otherwise impossible delta value.
+type CaseRange struct {
+	Lo    uint32
+	Hi    uint32
+	Delta d
+}
+
+// SpecialCase represents language-specific case mappings such as Turkish.
+// Methods of SpecialCase customize (by overriding) the standard mappings.
+type SpecialCase []CaseRange
+
+// BUG(r): There is no mechanism for full case folding, that is, for
+// characters that involve multiple runes in the input or output.
+
+// Indices into the Delta arrays inside CaseRanges for case mapping.
+const (
+	UpperCase = iota
+	LowerCase
+	TitleCase
+	MaxCase
+)
+
+type d [MaxCase]rune // to make the CaseRanges text shorter
+
+// If the Delta field of a CaseRange is UpperLower, it means
+// this CaseRange represents a sequence of the form (say)
+// Upper Lower Upper Lower.
+const (
+	UpperLower = MaxRune + 1 // (Cannot be a valid delta.)
+)
+
+// linearMax is the maximum size table for linear search for non-Latin1 rune.
+// Derived by running 'go test -calibrate'.
+const linearMax = 18
+
+// is16 reports whether r is in the sorted slice of 16-bit ranges.
+func is16(ranges []Range16, r uint16) bool {
+	if len(ranges) <= linearMax || r <= MaxLatin1 {
+		for i := range ranges {
+			range_ := &ranges[i]
+			if r < range_.Lo {
+				return false
+			}
+			if r <= range_.Hi {
+				return range_.Stride == 1 || (r-range_.Lo)%range_.Stride == 0
+			}
+		}
+		return false
+	}
+
+	// binary search over ranges
+	lo := 0
+	hi := len(ranges)
+	for lo < hi {
+		m := lo + (hi-lo)/2
+		range_ := &ranges[m]
+		if range_.Lo <= r && r <= range_.Hi {
+			return range_.Stride == 1 || (r-range_.Lo)%range_.Stride == 0
+		}
+		if r < range_.Lo {
+			hi = m
+		} else {
+			lo = m + 1
+		}
+	}
+	return false
+}
+
+// is32 reports whether r is in the sorted slice of 32-bit ranges.
+func is32(ranges []Range32, r uint32) bool {
+	if len(ranges) <= linearMax {
+		for i := range ranges {
+			range_ := &ranges[i]
+			if r < range_.Lo {
+				return false
+			}
+			if r <= range_.Hi {
+				return range_.Stride == 1 || (r-range_.Lo)%range_.Stride == 0
+			}
+		}
+		return false
+	}
+
+	// binary search over ranges
+	lo := 0
+	hi := len(ranges)
+	for lo < hi {
+		m := lo + (hi-lo)/2
+		range_ := ranges[m]
+		if range_.Lo <= r && r <= range_.Hi {
+			return range_.Stride == 1 || (r-range_.Lo)%range_.Stride == 0
+		}
+		if r < range_.Lo {
+			hi = m
+		} else {
+			lo = m + 1
+		}
+	}
+	return false
+}
+
+// Is reports whether the rune is in the specified table of ranges.
+func Is(rangeTab *RangeTable, r rune) bool {
+	r16 := rangeTab.R16
+	// Compare as uint32 to correctly handle negative runes.
+	if len(r16) > 0 && uint32(r) <= uint32(r16[len(r16)-1].Hi) {
+		return is16(r16, uint16(r))
+	}
+	r32 := rangeTab.R32
+	if len(r32) > 0 && r >= rune(r32[0].Lo) {
+		return is32(r32, uint32(r))
+	}
+	return false
+}
+
+func isExcludingLatin(rangeTab *RangeTable, r rune) bool {
+	r16 := rangeTab.R16
+	// Compare as uint32 to correctly handle negative runes.
+	if off := rangeTab.LatinOffset; len(r16) > off && uint32(r) <= uint32(r16[len(r16)-1].Hi) {
+		return is16(r16[off:], uint16(r))
+	}
+	r32 := rangeTab.R32
+	if len(r32) > 0 && r >= rune(r32[0].Lo) {
+		return is32(r32, uint32(r))
+	}
+	return false
+}
+
+// IsUpper reports whether the rune is an upper case letter.
+func IsUpper(r rune) bool {
+	// See comment in IsGraphic.
+	if uint32(r) <= MaxLatin1 {
+		return properties[uint8(r)]&pLmask == pLu
+	}
+	return isExcludingLatin(Upper, r)
+}
+
+// IsLower reports whether the rune is a lower case letter.
+func IsLower(r rune) bool {
+	// See comment in IsGraphic.
+	if uint32(r) <= MaxLatin1 {
+		return properties[uint8(r)]&pLmask == pLl
+	}
+	return isExcludingLatin(Lower, r)
+}
+
+// IsTitle reports whether the rune is a title case letter.
+func IsTitle(r rune) bool {
+	if r <= MaxLatin1 {
+		return false
+	}
+	return isExcludingLatin(Title, r)
+}
+
+// to maps the rune using the specified case mapping.
+// It additionally reports whether caseRange contained a mapping for r.
+func to(_case int, r rune, caseRange []CaseRange) (mappedRune rune, foundMapping bool) {
+	if _case < 0 || MaxCase <= _case {
+		return ReplacementChar, false // as reasonable an error as any
+	}
+	// binary search over ranges
+	lo := 0
+	hi := len(caseRange)
+	for lo < hi {
+		m := lo + (hi-lo)/2
+		cr := caseRange[m]
+		if rune(cr.Lo) <= r && r <= rune(cr.Hi) {
+			delta := cr.Delta[_case]
+			if delta > MaxRune {
+				// In an Upper-Lower sequence, which always starts with
+				// an UpperCase letter, the real deltas always look like:
+				//	{0, 1, 0}    UpperCase (Lower is next)
+				//	{-1, 0, -1}  LowerCase (Upper, Title are previous)
+				// The characters at even offsets from the beginning of the
+				// sequence are upper case; the ones at odd offsets are lower.
+				// The correct mapping can be done by clearing or setting the low
+				// bit in the sequence offset.
+				// The constants UpperCase and TitleCase are even while LowerCase
+				// is odd so we take the low bit from _case.
+				return rune(cr.Lo) + ((r-rune(cr.Lo))&^1 | rune(_case&1)), true
+			}
+			return r + delta, true
+		}
+		if r < rune(cr.Lo) {
+			hi = m
+		} else {
+			lo = m + 1
+		}
+	}
+	return r, false
+}
+
+// To maps the rune to the specified case: UpperCase, LowerCase, or TitleCase.
+func To(_case int, r rune) rune {
+	r, _ = to(_case, r, CaseRanges)
+	return r
+}
+
+// ToUpper maps the rune to upper case.
+func ToUpper(r rune) rune {
+	if r <= MaxASCII {
+		if 'a' <= r && r <= 'z' {
+			r -= 'a' - 'A'
+		}
+		return r
+	}
+	return To(UpperCase, r)
+}
+
+// ToLower maps the rune to lower case.
+func ToLower(r rune) rune {
+	if r <= MaxASCII {
+		if 'A' <= r && r <= 'Z' {
+			r += 'a' - 'A'
+		}
+		return r
+	}
+	return To(LowerCase, r)
+}
+
+// ToTitle maps the rune to title case.
+func ToTitle(r rune) rune {
+	if r <= MaxASCII {
+		if 'a' <= r && r <= 'z' { // title case is upper case for ASCII
+			r -= 'a' - 'A'
+		}
+		return r
+	}
+	return To(TitleCase, r)
+}
+
+// ToUpper maps the rune to upper case giving priority to the special mapping.
+func (special SpecialCase) ToUpper(r rune) rune {
+	r1, hadMapping := to(UpperCase, r, []CaseRange(special))
+	if r1 == r && !hadMapping {
+		r1 = ToUpper(r)
+	}
+	return r1
+}
+
+// ToTitle maps the rune to title case giving priority to the special mapping.
+func (special SpecialCase) ToTitle(r rune) rune {
+	r1, hadMapping := to(TitleCase, r, []CaseRange(special))
+	if r1 == r && !hadMapping {
+		r1 = ToTitle(r)
+	}
+	return r1
+}
+
+// ToLower maps the rune to lower case giving priority to the special mapping.
+func (special SpecialCase) ToLower(r rune) rune {
+	r1, hadMapping := to(LowerCase, r, []CaseRange(special))
+	if r1 == r && !hadMapping {
+		r1 = ToLower(r)
+	}
+	return r1
+}
+
+// caseOrbit is defined in tables.go as []foldPair. Right now all the
+// entries fit in uint16, so use uint16. If that changes, compilation
+// will fail (the constants in the composite literal will not fit in uint16)
+// and the types here can change to uint32.
+type foldPair struct {
+	From uint16
+	To   uint16
+}
+
+// SimpleFold iterates over Unicode code points equivalent under
+// the Unicode-defined simple case folding. Among the code points
+// equivalent to rune (including rune itself), SimpleFold returns the
+// smallest rune > r if one exists, or else the smallest rune >= 0.
+// If r is not a valid Unicode code point, SimpleFold(r) returns r.
+//
+// For example:
+//
+//	SimpleFold('A') = 'a'
+//	SimpleFold('a') = 'A'
+//
+//	SimpleFold('K') = 'k'
+//	SimpleFold('k') = '\u212A' (Kelvin symbol, K)
+//	SimpleFold('\u212A') = 'K'
+//
+//	SimpleFold('1') = '1'
+//
+//	SimpleFold(-2) = -2
+func SimpleFold(r rune) rune {
+	if r < 0 || r > MaxRune {
+		return r
+	}
+
+	if int(r) < len(asciiFold) {
+		return rune(asciiFold[r])
+	}
+
+	// Consult caseOrbit table for special cases.
+	lo := 0
+	hi := len(caseOrbit)
+	for lo < hi {
+		m := lo + (hi-lo)/2
+		if rune(caseOrbit[m].From) < r {
+			lo = m + 1
+		} else {
+			hi = m
+		}
+	}
+	if lo < len(caseOrbit) && rune(caseOrbit[lo].From) == r {
+		return rune(caseOrbit[lo].To)
+	}
+
+	// No folding specified. This is a one- or two-element
+	// equivalence class containing rune and ToLower(rune)
+	// and ToUpper(rune) if they are different from rune.
+	if l := ToLower(r); l != r {
+		return l
+	}
+	return ToUpper(r)
+}
diff --git a/contrib/go/_std_1.18/src/unicode/tables.go b/contrib/go/_std_1.19/src/unicode/tables.go
index a9b23bfacd..a9b23bfacd 100644
--- a/contrib/go/_std_1.18/src/unicode/tables.go
+++ b/contrib/go/_std_1.19/src/unicode/tables.go
diff --git a/contrib/go/_std_1.18/src/unicode/utf16/utf16.go b/contrib/go/_std_1.19/src/unicode/utf16/utf16.go
index 1a881aa769..1a881aa769 100644
--- a/contrib/go/_std_1.18/src/unicode/utf16/utf16.go
+++ b/contrib/go/_std_1.19/src/unicode/utf16/utf16.go
diff --git a/contrib/go/_std_1.19/src/unicode/utf8/utf8.go b/contrib/go/_std_1.19/src/unicode/utf8/utf8.go
new file mode 100644
index 0000000000..1e9f666e23
--- /dev/null
+++ b/contrib/go/_std_1.19/src/unicode/utf8/utf8.go
@@ -0,0 +1,583 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package utf8 implements functions and constants to support text encoded in
+// UTF-8. It includes functions to translate between runes and UTF-8 byte sequences.
+// See https://en.wikipedia.org/wiki/UTF-8
+package utf8
+
+// The conditions RuneError==unicode.ReplacementChar and
+// MaxRune==unicode.MaxRune are verified in the tests.
+// Defining them locally avoids this package depending on package unicode.
+
+// Numbers fundamental to the encoding.
+const (
+	RuneError = '\uFFFD'     // the "error" Rune or "Unicode replacement character"
+	RuneSelf  = 0x80         // characters below RuneSelf are represented as themselves in a single byte.
+	MaxRune   = '\U0010FFFF' // Maximum valid Unicode code point.
+	UTFMax    = 4            // maximum number of bytes of a UTF-8 encoded Unicode character.
+)
+
+// Code points in the surrogate range are not valid for UTF-8.
+const (
+	surrogateMin = 0xD800
+	surrogateMax = 0xDFFF
+)
+
+const (
+	t1 = 0b00000000
+	tx = 0b10000000
+	t2 = 0b11000000
+	t3 = 0b11100000
+	t4 = 0b11110000
+	t5 = 0b11111000
+
+	maskx = 0b00111111
+	mask2 = 0b00011111
+	mask3 = 0b00001111
+	mask4 = 0b00000111
+
+	rune1Max = 1<<7 - 1
+	rune2Max = 1<<11 - 1
+	rune3Max = 1<<16 - 1
+
+	// The default lowest and highest continuation byte.
+	locb = 0b10000000
+	hicb = 0b10111111
+
+	// These names of these constants are chosen to give nice alignment in the
+	// table below. The first nibble is an index into acceptRanges or F for
+	// special one-byte cases. The second nibble is the Rune length or the
+	// Status for the special one-byte case.
+	xx = 0xF1 // invalid: size 1
+	as = 0xF0 // ASCII: size 1
+	s1 = 0x02 // accept 0, size 2
+	s2 = 0x13 // accept 1, size 3
+	s3 = 0x03 // accept 0, size 3
+	s4 = 0x23 // accept 2, size 3
+	s5 = 0x34 // accept 3, size 4
+	s6 = 0x04 // accept 0, size 4
+	s7 = 0x44 // accept 4, size 4
+)
+
+// first is information about the first byte in a UTF-8 sequence.
+var first = [256]uint8{
+	//   1   2   3   4   5   6   7   8   9   A   B   C   D   E   F
+	as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, // 0x00-0x0F
+	as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, // 0x10-0x1F
+	as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, // 0x20-0x2F
+	as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, // 0x30-0x3F
+	as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, // 0x40-0x4F
+	as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, // 0x50-0x5F
+	as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, // 0x60-0x6F
+	as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, as, // 0x70-0x7F
+	//   1   2   3   4   5   6   7   8   9   A   B   C   D   E   F
+	xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, // 0x80-0x8F
+	xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, // 0x90-0x9F
+	xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, // 0xA0-0xAF
+	xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, // 0xB0-0xBF
+	xx, xx, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, // 0xC0-0xCF
+	s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, s1, // 0xD0-0xDF
+	s2, s3, s3, s3, s3, s3, s3, s3, s3, s3, s3, s3, s3, s4, s3, s3, // 0xE0-0xEF
+	s5, s6, s6, s6, s7, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, xx, // 0xF0-0xFF
+}
+
+// acceptRange gives the range of valid values for the second byte in a UTF-8
+// sequence.
+type acceptRange struct {
+	lo uint8 // lowest value for second byte.
+	hi uint8 // highest value for second byte.
+}
+
+// acceptRanges has size 16 to avoid bounds checks in the code that uses it.
+var acceptRanges = [16]acceptRange{
+	0: {locb, hicb},
+	1: {0xA0, hicb},
+	2: {locb, 0x9F},
+	3: {0x90, hicb},
+	4: {locb, 0x8F},
+}
+
+// FullRune reports whether the bytes in p begin with a full UTF-8 encoding of a rune.
+// An invalid encoding is considered a full Rune since it will convert as a width-1 error rune.
+func FullRune(p []byte) bool {
+	n := len(p)
+	if n == 0 {
+		return false
+	}
+	x := first[p[0]]
+	if n >= int(x&7) {
+		return true // ASCII, invalid or valid.
+	}
+	// Must be short or invalid.
+	accept := acceptRanges[x>>4]
+	if n > 1 && (p[1] < accept.lo || accept.hi < p[1]) {
+		return true
+	} else if n > 2 && (p[2] < locb || hicb < p[2]) {
+		return true
+	}
+	return false
+}
+
+// FullRuneInString is like FullRune but its input is a string.
+func FullRuneInString(s string) bool {
+	n := len(s)
+	if n == 0 {
+		return false
+	}
+	x := first[s[0]]
+	if n >= int(x&7) {
+		return true // ASCII, invalid, or valid.
+	}
+	// Must be short or invalid.
+	accept := acceptRanges[x>>4]
+	if n > 1 && (s[1] < accept.lo || accept.hi < s[1]) {
+		return true
+	} else if n > 2 && (s[2] < locb || hicb < s[2]) {
+		return true
+	}
+	return false
+}
+
+// DecodeRune unpacks the first UTF-8 encoding in p and returns the rune and
+// its width in bytes. If p is empty it returns (RuneError, 0). Otherwise, if
+// the encoding is invalid, it returns (RuneError, 1). Both are impossible
+// results for correct, non-empty UTF-8.
+//
+// An encoding is invalid if it is incorrect UTF-8, encodes a rune that is
+// out of range, or is not the shortest possible UTF-8 encoding for the
+// value. No other validation is performed.
+func DecodeRune(p []byte) (r rune, size int) {
+	n := len(p)
+	if n < 1 {
+		return RuneError, 0
+	}
+	p0 := p[0]
+	x := first[p0]
+	if x >= as {
+		// The following code simulates an additional check for x == xx and
+		// handling the ASCII and invalid cases accordingly. This mask-and-or
+		// approach prevents an additional branch.
+		mask := rune(x) << 31 >> 31 // Create 0x0000 or 0xFFFF.
+		return rune(p[0])&^mask | RuneError&mask, 1
+	}
+	sz := int(x & 7)
+	accept := acceptRanges[x>>4]
+	if n < sz {
+		return RuneError, 1
+	}
+	b1 := p[1]
+	if b1 < accept.lo || accept.hi < b1 {
+		return RuneError, 1
+	}
+	if sz <= 2 { // <= instead of == to help the compiler eliminate some bounds checks
+		return rune(p0&mask2)<<6 | rune(b1&maskx), 2
+	}
+	b2 := p[2]
+	if b2 < locb || hicb < b2 {
+		return RuneError, 1
+	}
+	if sz <= 3 {
+		return rune(p0&mask3)<<12 | rune(b1&maskx)<<6 | rune(b2&maskx), 3
+	}
+	b3 := p[3]
+	if b3 < locb || hicb < b3 {
+		return RuneError, 1
+	}
+	return rune(p0&mask4)<<18 | rune(b1&maskx)<<12 | rune(b2&maskx)<<6 | rune(b3&maskx), 4
+}
+
+// DecodeRuneInString is like DecodeRune but its input is a string. If s is
+// empty it returns (RuneError, 0). Otherwise, if the encoding is invalid, it
+// returns (RuneError, 1). Both are impossible results for correct, non-empty
+// UTF-8.
+//
+// An encoding is invalid if it is incorrect UTF-8, encodes a rune that is
+// out of range, or is not the shortest possible UTF-8 encoding for the
+// value. No other validation is performed.
+func DecodeRuneInString(s string) (r rune, size int) {
+	n := len(s)
+	if n < 1 {
+		return RuneError, 0
+	}
+	s0 := s[0]
+	x := first[s0]
+	if x >= as {
+		// The following code simulates an additional check for x == xx and
+		// handling the ASCII and invalid cases accordingly. This mask-and-or
+		// approach prevents an additional branch.
+		mask := rune(x) << 31 >> 31 // Create 0x0000 or 0xFFFF.
+		return rune(s[0])&^mask | RuneError&mask, 1
+	}
+	sz := int(x & 7)
+	accept := acceptRanges[x>>4]
+	if n < sz {
+		return RuneError, 1
+	}
+	s1 := s[1]
+	if s1 < accept.lo || accept.hi < s1 {
+		return RuneError, 1
+	}
+	if sz <= 2 { // <= instead of == to help the compiler eliminate some bounds checks
+		return rune(s0&mask2)<<6 | rune(s1&maskx), 2
+	}
+	s2 := s[2]
+	if s2 < locb || hicb < s2 {
+		return RuneError, 1
+	}
+	if sz <= 3 {
+		return rune(s0&mask3)<<12 | rune(s1&maskx)<<6 | rune(s2&maskx), 3
+	}
+	s3 := s[3]
+	if s3 < locb || hicb < s3 {
+		return RuneError, 1
+	}
+	return rune(s0&mask4)<<18 | rune(s1&maskx)<<12 | rune(s2&maskx)<<6 | rune(s3&maskx), 4
+}
+
+// DecodeLastRune unpacks the last UTF-8 encoding in p and returns the rune and
+// its width in bytes. If p is empty it returns (RuneError, 0). Otherwise, if
+// the encoding is invalid, it returns (RuneError, 1). Both are impossible
+// results for correct, non-empty UTF-8.
+//
+// An encoding is invalid if it is incorrect UTF-8, encodes a rune that is
+// out of range, or is not the shortest possible UTF-8 encoding for the
+// value. No other validation is performed.
+func DecodeLastRune(p []byte) (r rune, size int) {
+	end := len(p)
+	if end == 0 {
+		return RuneError, 0
+	}
+	start := end - 1
+	r = rune(p[start])
+	if r < RuneSelf {
+		return r, 1
+	}
+	// guard against O(n^2) behavior when traversing
+	// backwards through strings with long sequences of
+	// invalid UTF-8.
+	lim := end - UTFMax
+	if lim < 0 {
+		lim = 0
+	}
+	for start--; start >= lim; start-- {
+		if RuneStart(p[start]) {
+			break
+		}
+	}
+	if start < 0 {
+		start = 0
+	}
+	r, size = DecodeRune(p[start:end])
+	if start+size != end {
+		return RuneError, 1
+	}
+	return r, size
+}
+
+// DecodeLastRuneInString is like DecodeLastRune but its input is a string. If
+// s is empty it returns (RuneError, 0). Otherwise, if the encoding is invalid,
+// it returns (RuneError, 1). Both are impossible results for correct,
+// non-empty UTF-8.
+//
+// An encoding is invalid if it is incorrect UTF-8, encodes a rune that is
+// out of range, or is not the shortest possible UTF-8 encoding for the
+// value. No other validation is performed.
+func DecodeLastRuneInString(s string) (r rune, size int) {
+	end := len(s)
+	if end == 0 {
+		return RuneError, 0
+	}
+	start := end - 1
+	r = rune(s[start])
+	if r < RuneSelf {
+		return r, 1
+	}
+	// guard against O(n^2) behavior when traversing
+	// backwards through strings with long sequences of
+	// invalid UTF-8.
+	lim := end - UTFMax
+	if lim < 0 {
+		lim = 0
+	}
+	for start--; start >= lim; start-- {
+		if RuneStart(s[start]) {
+			break
+		}
+	}
+	if start < 0 {
+		start = 0
+	}
+	r, size = DecodeRuneInString(s[start:end])
+	if start+size != end {
+		return RuneError, 1
+	}
+	return r, size
+}
+
+// RuneLen returns the number of bytes required to encode the rune.
+// It returns -1 if the rune is not a valid value to encode in UTF-8.
+func RuneLen(r rune) int {
+	switch {
+	case r < 0:
+		return -1
+	case r <= rune1Max:
+		return 1
+	case r <= rune2Max:
+		return 2
+	case surrogateMin <= r && r <= surrogateMax:
+		return -1
+	case r <= rune3Max:
+		return 3
+	case r <= MaxRune:
+		return 4
+	}
+	return -1
+}
+
+// EncodeRune writes into p (which must be large enough) the UTF-8 encoding of the rune.
+// If the rune is out of range, it writes the encoding of RuneError.
+// It returns the number of bytes written.
+func EncodeRune(p []byte, r rune) int {
+	// Negative values are erroneous. Making it unsigned addresses the problem.
+	switch i := uint32(r); {
+	case i <= rune1Max:
+		p[0] = byte(r)
+		return 1
+	case i <= rune2Max:
+		_ = p[1] // eliminate bounds checks
+		p[0] = t2 | byte(r>>6)
+		p[1] = tx | byte(r)&maskx
+		return 2
+	case i > MaxRune, surrogateMin <= i && i <= surrogateMax:
+		r = RuneError
+		fallthrough
+	case i <= rune3Max:
+		_ = p[2] // eliminate bounds checks
+		p[0] = t3 | byte(r>>12)
+		p[1] = tx | byte(r>>6)&maskx
+		p[2] = tx | byte(r)&maskx
+		return 3
+	default:
+		_ = p[3] // eliminate bounds checks
+		p[0] = t4 | byte(r>>18)
+		p[1] = tx | byte(r>>12)&maskx
+		p[2] = tx | byte(r>>6)&maskx
+		p[3] = tx | byte(r)&maskx
+		return 4
+	}
+}
+
+// AppendRune appends the UTF-8 encoding of r to the end of p and
+// returns the extended buffer. If the rune is out of range,
+// it appends the encoding of RuneError.
+func AppendRune(p []byte, r rune) []byte {
+	// This function is inlineable for fast handling of ASCII.
+	if uint32(r) <= rune1Max {
+		return append(p, byte(r))
+	}
+	return appendRuneNonASCII(p, r)
+}
+
+func appendRuneNonASCII(p []byte, r rune) []byte {
+	// Negative values are erroneous. Making it unsigned addresses the problem.
+	switch i := uint32(r); {
+	case i <= rune2Max:
+		return append(p, t2|byte(r>>6), tx|byte(r)&maskx)
+	case i > MaxRune, surrogateMin <= i && i <= surrogateMax:
+		r = RuneError
+		fallthrough
+	case i <= rune3Max:
+		return append(p, t3|byte(r>>12), tx|byte(r>>6)&maskx, tx|byte(r)&maskx)
+	default:
+		return append(p, t4|byte(r>>18), tx|byte(r>>12)&maskx, tx|byte(r>>6)&maskx, tx|byte(r)&maskx)
+	}
+}
+
+// RuneCount returns the number of runes in p. Erroneous and short
+// encodings are treated as single runes of width 1 byte.
+func RuneCount(p []byte) int {
+	np := len(p)
+	var n int
+	for i := 0; i < np; {
+		n++
+		c := p[i]
+		if c < RuneSelf {
+			// ASCII fast path
+			i++
+			continue
+		}
+		x := first[c]
+		if x == xx {
+			i++ // invalid.
+			continue
+		}
+		size := int(x & 7)
+		if i+size > np {
+			i++ // Short or invalid.
+			continue
+		}
+		accept := acceptRanges[x>>4]
+		if c := p[i+1]; c < accept.lo || accept.hi < c {
+			size = 1
+		} else if size == 2 {
+		} else if c := p[i+2]; c < locb || hicb < c {
+			size = 1
+		} else if size == 3 {
+		} else if c := p[i+3]; c < locb || hicb < c {
+			size = 1
+		}
+		i += size
+	}
+	return n
+}
+
+// RuneCountInString is like RuneCount but its input is a string.
+func RuneCountInString(s string) (n int) {
+	ns := len(s)
+	for i := 0; i < ns; n++ {
+		c := s[i]
+		if c < RuneSelf {
+			// ASCII fast path
+			i++
+			continue
+		}
+		x := first[c]
+		if x == xx {
+			i++ // invalid.
+			continue
+		}
+		size := int(x & 7)
+		if i+size > ns {
+			i++ // Short or invalid.
+			continue
+		}
+		accept := acceptRanges[x>>4]
+		if c := s[i+1]; c < accept.lo || accept.hi < c {
+			size = 1
+		} else if size == 2 {
+		} else if c := s[i+2]; c < locb || hicb < c {
+			size = 1
+		} else if size == 3 {
+		} else if c := s[i+3]; c < locb || hicb < c {
+			size = 1
+		}
+		i += size
+	}
+	return n
+}
+
+// RuneStart reports whether the byte could be the first byte of an encoded,
+// possibly invalid rune. Second and subsequent bytes always have the top two
+// bits set to 10.
+func RuneStart(b byte) bool { return b&0xC0 != 0x80 }
+
+// Valid reports whether p consists entirely of valid UTF-8-encoded runes.
+func Valid(p []byte) bool {
+	// This optimization avoids the need to recompute the capacity
+	// when generating code for p[8:], bringing it to parity with
+	// ValidString, which was 20% faster on long ASCII strings.
+	p = p[:len(p):len(p)]
+
+	// Fast path. Check for and skip 8 bytes of ASCII characters per iteration.
+	for len(p) >= 8 {
+		// Combining two 32 bit loads allows the same code to be used
+		// for 32 and 64 bit platforms.
+		// The compiler can generate a 32bit load for first32 and second32
+		// on many platforms. See test/codegen/memcombine.go.
+		first32 := uint32(p[0]) | uint32(p[1])<<8 | uint32(p[2])<<16 | uint32(p[3])<<24
+		second32 := uint32(p[4]) | uint32(p[5])<<8 | uint32(p[6])<<16 | uint32(p[7])<<24
+		if (first32|second32)&0x80808080 != 0 {
+			// Found a non ASCII byte (>= RuneSelf).
+			break
+		}
+		p = p[8:]
+	}
+	n := len(p)
+	for i := 0; i < n; {
+		pi := p[i]
+		if pi < RuneSelf {
+			i++
+			continue
+		}
+		x := first[pi]
+		if x == xx {
+			return false // Illegal starter byte.
+		}
+		size := int(x & 7)
+		if i+size > n {
+			return false // Short or invalid.
+		}
+		accept := acceptRanges[x>>4]
+		if c := p[i+1]; c < accept.lo || accept.hi < c {
+			return false
+		} else if size == 2 {
+		} else if c := p[i+2]; c < locb || hicb < c {
+			return false
+		} else if size == 3 {
+		} else if c := p[i+3]; c < locb || hicb < c {
+			return false
+		}
+		i += size
+	}
+	return true
+}
+
+// ValidString reports whether s consists entirely of valid UTF-8-encoded runes.
+func ValidString(s string) bool {
+	// Fast path. Check for and skip 8 bytes of ASCII characters per iteration.
+	for len(s) >= 8 {
+		// Combining two 32 bit loads allows the same code to be used
+		// for 32 and 64 bit platforms.
+		// The compiler can generate a 32bit load for first32 and second32
+		// on many platforms. See test/codegen/memcombine.go.
+		first32 := uint32(s[0]) | uint32(s[1])<<8 | uint32(s[2])<<16 | uint32(s[3])<<24
+		second32 := uint32(s[4]) | uint32(s[5])<<8 | uint32(s[6])<<16 | uint32(s[7])<<24
+		if (first32|second32)&0x80808080 != 0 {
+			// Found a non ASCII byte (>= RuneSelf).
+			break
+		}
+		s = s[8:]
+	}
+	n := len(s)
+	for i := 0; i < n; {
+		si := s[i]
+		if si < RuneSelf {
+			i++
+			continue
+		}
+		x := first[si]
+		if x == xx {
+			return false // Illegal starter byte.
+		}
+		size := int(x & 7)
+		if i+size > n {
+			return false // Short or invalid.
+		}
+		accept := acceptRanges[x>>4]
+		if c := s[i+1]; c < accept.lo || accept.hi < c {
+			return false
+		} else if size == 2 {
+		} else if c := s[i+2]; c < locb || hicb < c {
+			return false
+		} else if size == 3 {
+		} else if c := s[i+3]; c < locb || hicb < c {
+			return false
+		}
+		i += size
+	}
+	return true
+}
+
+// ValidRune reports whether r can be legally encoded as UTF-8.
+// Code points that are out of range or a surrogate half are illegal.
+func ValidRune(r rune) bool {
+	switch {
+	case 0 <= r && r < surrogateMin:
+		return true
+	case surrogateMax < r && r <= MaxRune:
+		return true
+	}
+	return false
+}
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/chacha20/chacha_generic.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/chacha20/chacha_generic.go
index a2ecf5c325..a2ecf5c325 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/chacha20/chacha_generic.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/chacha20/chacha_generic.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/chacha20/chacha_noasm.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/chacha20/chacha_noasm.go
index 025b49897e..025b49897e 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/chacha20/chacha_noasm.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/chacha20/chacha_noasm.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/chacha20/xor.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/chacha20/xor.go
index c2d04851e0..c2d04851e0 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/chacha20/xor.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/chacha20/xor.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305.go
index 93da7322bc..93da7322bc 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305_amd64.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305_amd64.go
index 25959b9a6e..25959b9a6e 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305_amd64.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305_amd64.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305_amd64.s b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305_amd64.s
index 867c181a14..867c181a14 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305_amd64.s
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305_amd64.s
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305_generic.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305_generic.go
index 96b2fd898b..96b2fd898b 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305_generic.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305_generic.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/chacha20poly1305/xchacha20poly1305.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/chacha20poly1305/xchacha20poly1305.go
index 1cebfe946f..1cebfe946f 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/chacha20poly1305/xchacha20poly1305.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/chacha20poly1305/xchacha20poly1305.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/cryptobyte/asn1.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/cryptobyte/asn1.go
index 3a1674a1e5..3a1674a1e5 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/cryptobyte/asn1.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/cryptobyte/asn1.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/cryptobyte/asn1/asn1.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/cryptobyte/asn1/asn1.go
index cda8e3edfd..cda8e3edfd 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/cryptobyte/asn1/asn1.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/cryptobyte/asn1/asn1.go
diff --git a/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/cryptobyte/builder.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/cryptobyte/builder.go
new file mode 100644
index 0000000000..c7ded75771
--- /dev/null
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/cryptobyte/builder.go
@@ -0,0 +1,337 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cryptobyte
+
+import (
+	"errors"
+	"fmt"
+)
+
+// A Builder builds byte strings from fixed-length and length-prefixed values.
+// Builders either allocate space as needed, or are ‘fixed’, which means that
+// they write into a given buffer and produce an error if it's exhausted.
+//
+// The zero value is a usable Builder that allocates space as needed.
+//
+// Simple values are marshaled and appended to a Builder using methods on the
+// Builder. Length-prefixed values are marshaled by providing a
+// BuilderContinuation, which is a function that writes the inner contents of
+// the value to a given Builder. See the documentation for BuilderContinuation
+// for details.
+type Builder struct {
+	err            error
+	result         []byte
+	fixedSize      bool
+	child          *Builder
+	offset         int
+	pendingLenLen  int
+	pendingIsASN1  bool
+	inContinuation *bool
+}
+
+// NewBuilder creates a Builder that appends its output to the given buffer.
+// Like append(), the slice will be reallocated if its capacity is exceeded.
+// Use Bytes to get the final buffer.
+func NewBuilder(buffer []byte) *Builder {
+	return &Builder{
+		result: buffer,
+	}
+}
+
+// NewFixedBuilder creates a Builder that appends its output into the given
+// buffer. This builder does not reallocate the output buffer. Writes that
+// would exceed the buffer's capacity are treated as an error.
+func NewFixedBuilder(buffer []byte) *Builder {
+	return &Builder{
+		result:    buffer,
+		fixedSize: true,
+	}
+}
+
+// SetError sets the value to be returned as the error from Bytes. Writes
+// performed after calling SetError are ignored.
+func (b *Builder) SetError(err error) {
+	b.err = err
+}
+
+// Bytes returns the bytes written by the builder or an error if one has
+// occurred during building.
+func (b *Builder) Bytes() ([]byte, error) {
+	if b.err != nil {
+		return nil, b.err
+	}
+	return b.result[b.offset:], nil
+}
+
+// BytesOrPanic returns the bytes written by the builder or panics if an error
+// has occurred during building.
+func (b *Builder) BytesOrPanic() []byte {
+	if b.err != nil {
+		panic(b.err)
+	}
+	return b.result[b.offset:]
+}
+
+// AddUint8 appends an 8-bit value to the byte string.
+func (b *Builder) AddUint8(v uint8) {
+	b.add(byte(v))
+}
+
+// AddUint16 appends a big-endian, 16-bit value to the byte string.
+func (b *Builder) AddUint16(v uint16) {
+	b.add(byte(v>>8), byte(v))
+}
+
+// AddUint24 appends a big-endian, 24-bit value to the byte string. The highest
+// byte of the 32-bit input value is silently truncated.
+func (b *Builder) AddUint24(v uint32) {
+	b.add(byte(v>>16), byte(v>>8), byte(v))
+}
+
+// AddUint32 appends a big-endian, 32-bit value to the byte string.
+func (b *Builder) AddUint32(v uint32) {
+	b.add(byte(v>>24), byte(v>>16), byte(v>>8), byte(v))
+}
+
+// AddBytes appends a sequence of bytes to the byte string.
+func (b *Builder) AddBytes(v []byte) {
+	b.add(v...)
+}
+
+// BuilderContinuation is a continuation-passing interface for building
+// length-prefixed byte sequences. Builder methods for length-prefixed
+// sequences (AddUint8LengthPrefixed etc) will invoke the BuilderContinuation
+// supplied to them. The child builder passed to the continuation can be used
+// to build the content of the length-prefixed sequence. For example:
+//
+//	parent := cryptobyte.NewBuilder()
+//	parent.AddUint8LengthPrefixed(func (child *Builder) {
+//	  child.AddUint8(42)
+//	  child.AddUint8LengthPrefixed(func (grandchild *Builder) {
+//	    grandchild.AddUint8(5)
+//	  })
+//	})
+//
+// It is an error to write more bytes to the child than allowed by the reserved
+// length prefix. After the continuation returns, the child must be considered
+// invalid, i.e. users must not store any copies or references of the child
+// that outlive the continuation.
+//
+// If the continuation panics with a value of type BuildError then the inner
+// error will be returned as the error from Bytes. If the child panics
+// otherwise then Bytes will repanic with the same value.
+type BuilderContinuation func(child *Builder)
+
+// BuildError wraps an error. If a BuilderContinuation panics with this value,
+// the panic will be recovered and the inner error will be returned from
+// Builder.Bytes.
+type BuildError struct {
+	Err error
+}
+
+// AddUint8LengthPrefixed adds a 8-bit length-prefixed byte sequence.
+func (b *Builder) AddUint8LengthPrefixed(f BuilderContinuation) {
+	b.addLengthPrefixed(1, false, f)
+}
+
+// AddUint16LengthPrefixed adds a big-endian, 16-bit length-prefixed byte sequence.
+func (b *Builder) AddUint16LengthPrefixed(f BuilderContinuation) {
+	b.addLengthPrefixed(2, false, f)
+}
+
+// AddUint24LengthPrefixed adds a big-endian, 24-bit length-prefixed byte sequence.
+func (b *Builder) AddUint24LengthPrefixed(f BuilderContinuation) {
+	b.addLengthPrefixed(3, false, f)
+}
+
+// AddUint32LengthPrefixed adds a big-endian, 32-bit length-prefixed byte sequence.
+func (b *Builder) AddUint32LengthPrefixed(f BuilderContinuation) {
+	b.addLengthPrefixed(4, false, f)
+}
+
+func (b *Builder) callContinuation(f BuilderContinuation, arg *Builder) {
+	if !*b.inContinuation {
+		*b.inContinuation = true
+
+		defer func() {
+			*b.inContinuation = false
+
+			r := recover()
+			if r == nil {
+				return
+			}
+
+			if buildError, ok := r.(BuildError); ok {
+				b.err = buildError.Err
+			} else {
+				panic(r)
+			}
+		}()
+	}
+
+	f(arg)
+}
+
+func (b *Builder) addLengthPrefixed(lenLen int, isASN1 bool, f BuilderContinuation) {
+	// Subsequent writes can be ignored if the builder has encountered an error.
+	if b.err != nil {
+		return
+	}
+
+	offset := len(b.result)
+	b.add(make([]byte, lenLen)...)
+
+	if b.inContinuation == nil {
+		b.inContinuation = new(bool)
+	}
+
+	b.child = &Builder{
+		result:         b.result,
+		fixedSize:      b.fixedSize,
+		offset:         offset,
+		pendingLenLen:  lenLen,
+		pendingIsASN1:  isASN1,
+		inContinuation: b.inContinuation,
+	}
+
+	b.callContinuation(f, b.child)
+	b.flushChild()
+	if b.child != nil {
+		panic("cryptobyte: internal error")
+	}
+}
+
+func (b *Builder) flushChild() {
+	if b.child == nil {
+		return
+	}
+	b.child.flushChild()
+	child := b.child
+	b.child = nil
+
+	if child.err != nil {
+		b.err = child.err
+		return
+	}
+
+	length := len(child.result) - child.pendingLenLen - child.offset
+
+	if length < 0 {
+		panic("cryptobyte: internal error") // result unexpectedly shrunk
+	}
+
+	if child.pendingIsASN1 {
+		// For ASN.1, we reserved a single byte for the length. If that turned out
+		// to be incorrect, we have to move the contents along in order to make
+		// space.
+		if child.pendingLenLen != 1 {
+			panic("cryptobyte: internal error")
+		}
+		var lenLen, lenByte uint8
+		if int64(length) > 0xfffffffe {
+			b.err = errors.New("pending ASN.1 child too long")
+			return
+		} else if length > 0xffffff {
+			lenLen = 5
+			lenByte = 0x80 | 4
+		} else if length > 0xffff {
+			lenLen = 4
+			lenByte = 0x80 | 3
+		} else if length > 0xff {
+			lenLen = 3
+			lenByte = 0x80 | 2
+		} else if length > 0x7f {
+			lenLen = 2
+			lenByte = 0x80 | 1
+		} else {
+			lenLen = 1
+			lenByte = uint8(length)
+			length = 0
+		}
+
+		// Insert the initial length byte, make space for successive length bytes,
+		// and adjust the offset.
+		child.result[child.offset] = lenByte
+		extraBytes := int(lenLen - 1)
+		if extraBytes != 0 {
+			child.add(make([]byte, extraBytes)...)
+			childStart := child.offset + child.pendingLenLen
+			copy(child.result[childStart+extraBytes:], child.result[childStart:])
+		}
+		child.offset++
+		child.pendingLenLen = extraBytes
+	}
+
+	l := length
+	for i := child.pendingLenLen - 1; i >= 0; i-- {
+		child.result[child.offset+i] = uint8(l)
+		l >>= 8
+	}
+	if l != 0 {
+		b.err = fmt.Errorf("cryptobyte: pending child length %d exceeds %d-byte length prefix", length, child.pendingLenLen)
+		return
+	}
+
+	if b.fixedSize && &b.result[0] != &child.result[0] {
+		panic("cryptobyte: BuilderContinuation reallocated a fixed-size buffer")
+	}
+
+	b.result = child.result
+}
+
+func (b *Builder) add(bytes ...byte) {
+	if b.err != nil {
+		return
+	}
+	if b.child != nil {
+		panic("cryptobyte: attempted write while child is pending")
+	}
+	if len(b.result)+len(bytes) < len(bytes) {
+		b.err = errors.New("cryptobyte: length overflow")
+	}
+	if b.fixedSize && len(b.result)+len(bytes) > cap(b.result) {
+		b.err = errors.New("cryptobyte: Builder is exceeding its fixed-size buffer")
+		return
+	}
+	b.result = append(b.result, bytes...)
+}
+
+// Unwrite rolls back n bytes written directly to the Builder. An attempt by a
+// child builder passed to a continuation to unwrite bytes from its parent will
+// panic.
+func (b *Builder) Unwrite(n int) {
+	if b.err != nil {
+		return
+	}
+	if b.child != nil {
+		panic("cryptobyte: attempted unwrite while child is pending")
+	}
+	length := len(b.result) - b.pendingLenLen - b.offset
+	if length < 0 {
+		panic("cryptobyte: internal error")
+	}
+	if n > length {
+		panic("cryptobyte: attempted to unwrite more than was written")
+	}
+	b.result = b.result[:len(b.result)-n]
+}
+
+// A MarshalingValue marshals itself into a Builder.
+type MarshalingValue interface {
+	// Marshal is called by Builder.AddValue. It receives a pointer to a builder
+	// to marshal itself into. It may return an error that occurred during
+	// marshaling, such as unset or invalid values.
+	Marshal(b *Builder) error
+}
+
+// AddValue calls Marshal on v, passing a pointer to the builder to append to.
+// If Marshal returns an error, it is set on the Builder so that subsequent
+// appends don't have an effect.
+func (b *Builder) AddValue(v MarshalingValue) {
+	err := v.Marshal(b)
+	if err != nil {
+		b.err = err
+	}
+}
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/cryptobyte/string.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/cryptobyte/string.go
index 589d297e6b..589d297e6b 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/cryptobyte/string.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/cryptobyte/string.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/curve25519/curve25519.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/curve25519/curve25519.go
index cda3fdd354..cda3fdd354 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/curve25519/curve25519.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/curve25519/curve25519.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/curve25519/internal/field/fe.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/curve25519/internal/field/fe.go
index ca841ad99e..ca841ad99e 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/curve25519/internal/field/fe.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/curve25519/internal/field/fe.go
diff --git a/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/curve25519/internal/field/fe_amd64.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/curve25519/internal/field/fe_amd64.go
new file mode 100644
index 0000000000..edcf163c4e
--- /dev/null
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/curve25519/internal/field/fe_amd64.go
@@ -0,0 +1,16 @@
+// Code generated by command: go run fe_amd64_asm.go -out ../fe_amd64.s -stubs ../fe_amd64.go -pkg field. DO NOT EDIT.
+
+//go:build amd64 && gc && !purego
+// +build amd64,gc,!purego
+
+package field
+
+// feMul sets out = a * b. It works like feMulGeneric.
+//
+//go:noescape
+func feMul(out *Element, a *Element, b *Element)
+
+// feSquare sets out = a * a. It works like feSquareGeneric.
+//
+//go:noescape
+func feSquare(out *Element, a *Element)
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/curve25519/internal/field/fe_amd64.s b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/curve25519/internal/field/fe_amd64.s
index 293f013c94..293f013c94 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/curve25519/internal/field/fe_amd64.s
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/curve25519/internal/field/fe_amd64.s
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/curve25519/internal/field/fe_arm64_noasm.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/curve25519/internal/field/fe_arm64_noasm.go
index 234a5b2e5d..234a5b2e5d 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/curve25519/internal/field/fe_arm64_noasm.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/curve25519/internal/field/fe_arm64_noasm.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/curve25519/internal/field/fe_generic.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/curve25519/internal/field/fe_generic.go
index 7b5b78cbd6..7b5b78cbd6 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/curve25519/internal/field/fe_generic.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/curve25519/internal/field/fe_generic.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/hkdf/hkdf.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/hkdf/hkdf.go
index dda3f143be..dda3f143be 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/hkdf/hkdf.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/hkdf/hkdf.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/internal/poly1305/bits_go1.13.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/internal/poly1305/bits_go1.13.go
index ed52b3418a..ed52b3418a 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/internal/poly1305/bits_go1.13.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/internal/poly1305/bits_go1.13.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/internal/poly1305/poly1305.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/internal/poly1305/poly1305.go
index 4aaea810a2..4aaea810a2 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/internal/poly1305/poly1305.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/internal/poly1305/poly1305.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/internal/poly1305/sum_amd64.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/internal/poly1305/sum_amd64.go
index 6d522333f2..6d522333f2 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/internal/poly1305/sum_amd64.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/internal/poly1305/sum_amd64.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/internal/poly1305/sum_amd64.s b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/internal/poly1305/sum_amd64.s
index 1d74f0f881..1d74f0f881 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/internal/poly1305/sum_amd64.s
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/internal/poly1305/sum_amd64.s
diff --git a/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/internal/poly1305/sum_generic.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/internal/poly1305/sum_generic.go
new file mode 100644
index 0000000000..e041da5ea3
--- /dev/null
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/internal/poly1305/sum_generic.go
@@ -0,0 +1,309 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file provides the generic implementation of Sum and MAC. Other files
+// might provide optimized assembly implementations of some of this code.
+
+package poly1305
+
+import "encoding/binary"
+
+// Poly1305 [RFC 7539] is a relatively simple algorithm: the authentication tag
+// for a 64 bytes message is approximately
+//
+//     s + m[0:16] * r⁴ + m[16:32] * r³ + m[32:48] * r² + m[48:64] * r  mod  2¹³⁰ - 5
+//
+// for some secret r and s. It can be computed sequentially like
+//
+//     for len(msg) > 0:
+//         h += read(msg, 16)
+//         h *= r
+//         h %= 2¹³⁰ - 5
+//     return h + s
+//
+// All the complexity is about doing performant constant-time math on numbers
+// larger than any available numeric type.
+
+func sumGeneric(out *[TagSize]byte, msg []byte, key *[32]byte) {
+	h := newMACGeneric(key)
+	h.Write(msg)
+	h.Sum(out)
+}
+
+func newMACGeneric(key *[32]byte) macGeneric {
+	m := macGeneric{}
+	initialize(key, &m.macState)
+	return m
+}
+
+// macState holds numbers in saturated 64-bit little-endian limbs. That is,
+// the value of [x0, x1, x2] is x[0] + x[1] * 2⁶⁴ + x[2] * 2¹²⁸.
+type macState struct {
+	// h is the main accumulator. It is to be interpreted modulo 2¹³⁰ - 5, but
+	// can grow larger during and after rounds. It must, however, remain below
+	// 2 * (2¹³⁰ - 5).
+	h [3]uint64
+	// r and s are the private key components.
+	r [2]uint64
+	s [2]uint64
+}
+
+type macGeneric struct {
+	macState
+
+	buffer [TagSize]byte
+	offset int
+}
+
+// Write splits the incoming message into TagSize chunks, and passes them to
+// update. It buffers incomplete chunks.
+func (h *macGeneric) Write(p []byte) (int, error) {
+	nn := len(p)
+	if h.offset > 0 {
+		n := copy(h.buffer[h.offset:], p)
+		if h.offset+n < TagSize {
+			h.offset += n
+			return nn, nil
+		}
+		p = p[n:]
+		h.offset = 0
+		updateGeneric(&h.macState, h.buffer[:])
+	}
+	if n := len(p) - (len(p) % TagSize); n > 0 {
+		updateGeneric(&h.macState, p[:n])
+		p = p[n:]
+	}
+	if len(p) > 0 {
+		h.offset += copy(h.buffer[h.offset:], p)
+	}
+	return nn, nil
+}
+
+// Sum flushes the last incomplete chunk from the buffer, if any, and generates
+// the MAC output. It does not modify its state, in order to allow for multiple
+// calls to Sum, even if no Write is allowed after Sum.
+func (h *macGeneric) Sum(out *[TagSize]byte) {
+	state := h.macState
+	if h.offset > 0 {
+		updateGeneric(&state, h.buffer[:h.offset])
+	}
+	finalize(out, &state.h, &state.s)
+}
+
+// [rMask0, rMask1] is the specified Poly1305 clamping mask in little-endian. It
+// clears some bits of the secret coefficient to make it possible to implement
+// multiplication more efficiently.
+const (
+	rMask0 = 0x0FFFFFFC0FFFFFFF
+	rMask1 = 0x0FFFFFFC0FFFFFFC
+)
+
+// initialize loads the 256-bit key into the two 128-bit secret values r and s.
+func initialize(key *[32]byte, m *macState) {
+	m.r[0] = binary.LittleEndian.Uint64(key[0:8]) & rMask0
+	m.r[1] = binary.LittleEndian.Uint64(key[8:16]) & rMask1
+	m.s[0] = binary.LittleEndian.Uint64(key[16:24])
+	m.s[1] = binary.LittleEndian.Uint64(key[24:32])
+}
+
+// uint128 holds a 128-bit number as two 64-bit limbs, for use with the
+// bits.Mul64 and bits.Add64 intrinsics.
+type uint128 struct {
+	lo, hi uint64
+}
+
+func mul64(a, b uint64) uint128 {
+	hi, lo := bitsMul64(a, b)
+	return uint128{lo, hi}
+}
+
+func add128(a, b uint128) uint128 {
+	lo, c := bitsAdd64(a.lo, b.lo, 0)
+	hi, c := bitsAdd64(a.hi, b.hi, c)
+	if c != 0 {
+		panic("poly1305: unexpected overflow")
+	}
+	return uint128{lo, hi}
+}
+
+func shiftRightBy2(a uint128) uint128 {
+	a.lo = a.lo>>2 | (a.hi&3)<<62
+	a.hi = a.hi >> 2
+	return a
+}
+
+// updateGeneric absorbs msg into the state.h accumulator. For each chunk m of
+// 128 bits of message, it computes
+//
+//	h₊ = (h + m) * r  mod  2¹³⁰ - 5
+//
+// If the msg length is not a multiple of TagSize, it assumes the last
+// incomplete chunk is the final one.
+func updateGeneric(state *macState, msg []byte) {
+	h0, h1, h2 := state.h[0], state.h[1], state.h[2]
+	r0, r1 := state.r[0], state.r[1]
+
+	for len(msg) > 0 {
+		var c uint64
+
+		// For the first step, h + m, we use a chain of bits.Add64 intrinsics.
+		// The resulting value of h might exceed 2¹³⁰ - 5, but will be partially
+		// reduced at the end of the multiplication below.
+		//
+		// The spec requires us to set a bit just above the message size, not to
+		// hide leading zeroes. For full chunks, that's 1 << 128, so we can just
+		// add 1 to the most significant (2¹²⁸) limb, h2.
+		if len(msg) >= TagSize {
+			h0, c = bitsAdd64(h0, binary.LittleEndian.Uint64(msg[0:8]), 0)
+			h1, c = bitsAdd64(h1, binary.LittleEndian.Uint64(msg[8:16]), c)
+			h2 += c + 1
+
+			msg = msg[TagSize:]
+		} else {
+			var buf [TagSize]byte
+			copy(buf[:], msg)
+			buf[len(msg)] = 1
+
+			h0, c = bitsAdd64(h0, binary.LittleEndian.Uint64(buf[0:8]), 0)
+			h1, c = bitsAdd64(h1, binary.LittleEndian.Uint64(buf[8:16]), c)
+			h2 += c
+
+			msg = nil
+		}
+
+		// Multiplication of big number limbs is similar to elementary school
+		// columnar multiplication. Instead of digits, there are 64-bit limbs.
+		//
+		// We are multiplying a 3 limbs number, h, by a 2 limbs number, r.
+		//
+		//                        h2    h1    h0  x
+		//                              r1    r0  =
+		//                       ----------------
+		//                      h2r0  h1r0  h0r0     <-- individual 128-bit products
+		//            +   h2r1  h1r1  h0r1
+		//               ------------------------
+		//                 m3    m2    m1    m0      <-- result in 128-bit overlapping limbs
+		//               ------------------------
+		//         m3.hi m2.hi m1.hi m0.hi           <-- carry propagation
+		//     +         m3.lo m2.lo m1.lo m0.lo
+		//        -------------------------------
+		//           t4    t3    t2    t1    t0      <-- final result in 64-bit limbs
+		//
+		// The main difference from pen-and-paper multiplication is that we do
+		// carry propagation in a separate step, as if we wrote two digit sums
+		// at first (the 128-bit limbs), and then carried the tens all at once.
+
+		h0r0 := mul64(h0, r0)
+		h1r0 := mul64(h1, r0)
+		h2r0 := mul64(h2, r0)
+		h0r1 := mul64(h0, r1)
+		h1r1 := mul64(h1, r1)
+		h2r1 := mul64(h2, r1)
+
+		// Since h2 is known to be at most 7 (5 + 1 + 1), and r0 and r1 have their
+		// top 4 bits cleared by rMask{0,1}, we know that their product is not going
+		// to overflow 64 bits, so we can ignore the high part of the products.
+		//
+		// This also means that the product doesn't have a fifth limb (t4).
+		if h2r0.hi != 0 {
+			panic("poly1305: unexpected overflow")
+		}
+		if h2r1.hi != 0 {
+			panic("poly1305: unexpected overflow")
+		}
+
+		m0 := h0r0
+		m1 := add128(h1r0, h0r1) // These two additions don't overflow thanks again
+		m2 := add128(h2r0, h1r1) // to the 4 masked bits at the top of r0 and r1.
+		m3 := h2r1
+
+		t0 := m0.lo
+		t1, c := bitsAdd64(m1.lo, m0.hi, 0)
+		t2, c := bitsAdd64(m2.lo, m1.hi, c)
+		t3, _ := bitsAdd64(m3.lo, m2.hi, c)
+
+		// Now we have the result as 4 64-bit limbs, and we need to reduce it
+		// modulo 2¹³⁰ - 5. The special shape of this Crandall prime lets us do
+		// a cheap partial reduction according to the reduction identity
+		//
+		//     c * 2¹³⁰ + n  =  c * 5 + n  mod  2¹³⁰ - 5
+		//
+		// because 2¹³⁰ = 5 mod 2¹³⁰ - 5. Partial reduction since the result is
+		// likely to be larger than 2¹³⁰ - 5, but still small enough to fit the
+		// assumptions we make about h in the rest of the code.
+		//
+		// See also https://speakerdeck.com/gtank/engineering-prime-numbers?slide=23
+
+		// We split the final result at the 2¹³⁰ mark into h and cc, the carry.
+		// Note that the carry bits are effectively shifted left by 2, in other
+		// words, cc = c * 4 for the c in the reduction identity.
+		h0, h1, h2 = t0, t1, t2&maskLow2Bits
+		cc := uint128{t2 & maskNotLow2Bits, t3}
+
+		// To add c * 5 to h, we first add cc = c * 4, and then add (cc >> 2) = c.
+
+		h0, c = bitsAdd64(h0, cc.lo, 0)
+		h1, c = bitsAdd64(h1, cc.hi, c)
+		h2 += c
+
+		cc = shiftRightBy2(cc)
+
+		h0, c = bitsAdd64(h0, cc.lo, 0)
+		h1, c = bitsAdd64(h1, cc.hi, c)
+		h2 += c
+
+		// h2 is at most 3 + 1 + 1 = 5, making the whole of h at most
+		//
+		//     5 * 2¹²⁸ + (2¹²⁸ - 1) = 6 * 2¹²⁸ - 1
+	}
+
+	state.h[0], state.h[1], state.h[2] = h0, h1, h2
+}
+
+const (
+	maskLow2Bits    uint64 = 0x0000000000000003
+	maskNotLow2Bits uint64 = ^maskLow2Bits
+)
+
+// select64 returns x if v == 1 and y if v == 0, in constant time.
+func select64(v, x, y uint64) uint64 { return ^(v-1)&x | (v-1)&y }
+
+// [p0, p1, p2] is 2¹³⁰ - 5 in little endian order.
+const (
+	p0 = 0xFFFFFFFFFFFFFFFB
+	p1 = 0xFFFFFFFFFFFFFFFF
+	p2 = 0x0000000000000003
+)
+
+// finalize completes the modular reduction of h and computes
+//
+//	out = h + s  mod  2¹²⁸
+func finalize(out *[TagSize]byte, h *[3]uint64, s *[2]uint64) {
+	h0, h1, h2 := h[0], h[1], h[2]
+
+	// After the partial reduction in updateGeneric, h might be more than
+	// 2¹³⁰ - 5, but will be less than 2 * (2¹³⁰ - 5). To complete the reduction
+	// in constant time, we compute t = h - (2¹³⁰ - 5), and select h as the
+	// result if the subtraction underflows, and t otherwise.
+
+	hMinusP0, b := bitsSub64(h0, p0, 0)
+	hMinusP1, b := bitsSub64(h1, p1, b)
+	_, b = bitsSub64(h2, p2, b)
+
+	// h = h if h < p else h - p
+	h0 = select64(b, h0, hMinusP0)
+	h1 = select64(b, h1, hMinusP1)
+
+	// Finally, we compute the last Poly1305 step
+	//
+	//     tag = h + s  mod  2¹²⁸
+	//
+	// by just doing a wide addition with the 128 low bits of h and discarding
+	// the overflow.
+	h0, c := bitsAdd64(h0, s[0], 0)
+	h1, _ = bitsAdd64(h1, s[1], c)
+
+	binary.LittleEndian.PutUint64(out[0:8], h0)
+	binary.LittleEndian.PutUint64(out[8:16], h1)
+}
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/internal/subtle/aliasing.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/internal/subtle/aliasing.go
index 4fad24f8dc..4fad24f8dc 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/crypto/internal/subtle/aliasing.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/crypto/internal/subtle/aliasing.go
diff --git a/contrib/go/_std_1.19/src/vendor/golang.org/x/net/dns/dnsmessage/message.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/dns/dnsmessage/message.go
new file mode 100644
index 0000000000..0cdf89f9ff
--- /dev/null
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/dns/dnsmessage/message.go
@@ -0,0 +1,2665 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package dnsmessage provides a mostly RFC 1035 compliant implementation of
+// DNS message packing and unpacking.
+//
+// The package also supports messages with Extension Mechanisms for DNS
+// (EDNS(0)) as defined in RFC 6891.
+//
+// This implementation is designed to minimize heap allocations and avoid
+// unnecessary packing and unpacking as much as possible.
+package dnsmessage
+
+import (
+	"errors"
+)
+
+// Message formats
+
+// A Type is a type of DNS request and response.
+type Type uint16
+
+const (
+	// ResourceHeader.Type and Question.Type
+	TypeA     Type = 1
+	TypeNS    Type = 2
+	TypeCNAME Type = 5
+	TypeSOA   Type = 6
+	TypePTR   Type = 12
+	TypeMX    Type = 15
+	TypeTXT   Type = 16
+	TypeAAAA  Type = 28
+	TypeSRV   Type = 33
+	TypeOPT   Type = 41
+
+	// Question.Type
+	TypeWKS   Type = 11
+	TypeHINFO Type = 13
+	TypeMINFO Type = 14
+	TypeAXFR  Type = 252
+	TypeALL   Type = 255
+)
+
+var typeNames = map[Type]string{
+	TypeA:     "TypeA",
+	TypeNS:    "TypeNS",
+	TypeCNAME: "TypeCNAME",
+	TypeSOA:   "TypeSOA",
+	TypePTR:   "TypePTR",
+	TypeMX:    "TypeMX",
+	TypeTXT:   "TypeTXT",
+	TypeAAAA:  "TypeAAAA",
+	TypeSRV:   "TypeSRV",
+	TypeOPT:   "TypeOPT",
+	TypeWKS:   "TypeWKS",
+	TypeHINFO: "TypeHINFO",
+	TypeMINFO: "TypeMINFO",
+	TypeAXFR:  "TypeAXFR",
+	TypeALL:   "TypeALL",
+}
+
+// String implements fmt.Stringer.String.
+func (t Type) String() string {
+	if n, ok := typeNames[t]; ok {
+		return n
+	}
+	return printUint16(uint16(t))
+}
+
+// GoString implements fmt.GoStringer.GoString.
+func (t Type) GoString() string {
+	if n, ok := typeNames[t]; ok {
+		return "dnsmessage." + n
+	}
+	return printUint16(uint16(t))
+}
+
+// A Class is a type of network.
+type Class uint16
+
+const (
+	// ResourceHeader.Class and Question.Class
+	ClassINET   Class = 1
+	ClassCSNET  Class = 2
+	ClassCHAOS  Class = 3
+	ClassHESIOD Class = 4
+
+	// Question.Class
+	ClassANY Class = 255
+)
+
+var classNames = map[Class]string{
+	ClassINET:   "ClassINET",
+	ClassCSNET:  "ClassCSNET",
+	ClassCHAOS:  "ClassCHAOS",
+	ClassHESIOD: "ClassHESIOD",
+	ClassANY:    "ClassANY",
+}
+
+// String implements fmt.Stringer.String.
+func (c Class) String() string {
+	if n, ok := classNames[c]; ok {
+		return n
+	}
+	return printUint16(uint16(c))
+}
+
+// GoString implements fmt.GoStringer.GoString.
+func (c Class) GoString() string {
+	if n, ok := classNames[c]; ok {
+		return "dnsmessage." + n
+	}
+	return printUint16(uint16(c))
+}
+
+// An OpCode is a DNS operation code.
+type OpCode uint16
+
+// GoString implements fmt.GoStringer.GoString.
+func (o OpCode) GoString() string {
+	return printUint16(uint16(o))
+}
+
+// An RCode is a DNS response status code.
+type RCode uint16
+
+// Header.RCode values.
+const (
+	RCodeSuccess        RCode = 0 // NoError
+	RCodeFormatError    RCode = 1 // FormErr
+	RCodeServerFailure  RCode = 2 // ServFail
+	RCodeNameError      RCode = 3 // NXDomain
+	RCodeNotImplemented RCode = 4 // NotImp
+	RCodeRefused        RCode = 5 // Refused
+)
+
+var rCodeNames = map[RCode]string{
+	RCodeSuccess:        "RCodeSuccess",
+	RCodeFormatError:    "RCodeFormatError",
+	RCodeServerFailure:  "RCodeServerFailure",
+	RCodeNameError:      "RCodeNameError",
+	RCodeNotImplemented: "RCodeNotImplemented",
+	RCodeRefused:        "RCodeRefused",
+}
+
+// String implements fmt.Stringer.String.
+func (r RCode) String() string {
+	if n, ok := rCodeNames[r]; ok {
+		return n
+	}
+	return printUint16(uint16(r))
+}
+
+// GoString implements fmt.GoStringer.GoString.
+func (r RCode) GoString() string {
+	if n, ok := rCodeNames[r]; ok {
+		return "dnsmessage." + n
+	}
+	return printUint16(uint16(r))
+}
+
+func printPaddedUint8(i uint8) string {
+	b := byte(i)
+	return string([]byte{
+		b/100 + '0',
+		b/10%10 + '0',
+		b%10 + '0',
+	})
+}
+
+func printUint8Bytes(buf []byte, i uint8) []byte {
+	b := byte(i)
+	if i >= 100 {
+		buf = append(buf, b/100+'0')
+	}
+	if i >= 10 {
+		buf = append(buf, b/10%10+'0')
+	}
+	return append(buf, b%10+'0')
+}
+
+func printByteSlice(b []byte) string {
+	if len(b) == 0 {
+		return ""
+	}
+	buf := make([]byte, 0, 5*len(b))
+	buf = printUint8Bytes(buf, uint8(b[0]))
+	for _, n := range b[1:] {
+		buf = append(buf, ',', ' ')
+		buf = printUint8Bytes(buf, uint8(n))
+	}
+	return string(buf)
+}
+
+const hexDigits = "0123456789abcdef"
+
+func printString(str []byte) string {
+	buf := make([]byte, 0, len(str))
+	for i := 0; i < len(str); i++ {
+		c := str[i]
+		if c == '.' || c == '-' || c == ' ' ||
+			'A' <= c && c <= 'Z' ||
+			'a' <= c && c <= 'z' ||
+			'0' <= c && c <= '9' {
+			buf = append(buf, c)
+			continue
+		}
+
+		upper := c >> 4
+		lower := (c << 4) >> 4
+		buf = append(
+			buf,
+			'\\',
+			'x',
+			hexDigits[upper],
+			hexDigits[lower],
+		)
+	}
+	return string(buf)
+}
+
+func printUint16(i uint16) string {
+	return printUint32(uint32(i))
+}
+
+func printUint32(i uint32) string {
+	// Max value is 4294967295.
+	buf := make([]byte, 10)
+	for b, d := buf, uint32(1000000000); d > 0; d /= 10 {
+		b[0] = byte(i/d%10 + '0')
+		if b[0] == '0' && len(b) == len(buf) && len(buf) > 1 {
+			buf = buf[1:]
+		}
+		b = b[1:]
+		i %= d
+	}
+	return string(buf)
+}
+
+func printBool(b bool) string {
+	if b {
+		return "true"
+	}
+	return "false"
+}
+
+var (
+	// ErrNotStarted indicates that the prerequisite information isn't
+	// available yet because the previous records haven't been appropriately
+	// parsed, skipped or finished.
+	ErrNotStarted = errors.New("parsing/packing of this type isn't available yet")
+
+	// ErrSectionDone indicated that all records in the section have been
+	// parsed or finished.
+	ErrSectionDone = errors.New("parsing/packing of this section has completed")
+
+	errBaseLen            = errors.New("insufficient data for base length type")
+	errCalcLen            = errors.New("insufficient data for calculated length type")
+	errReserved           = errors.New("segment prefix is reserved")
+	errTooManyPtr         = errors.New("too many pointers (>10)")
+	errInvalidPtr         = errors.New("invalid pointer")
+	errNilResouceBody     = errors.New("nil resource body")
+	errResourceLen        = errors.New("insufficient data for resource body length")
+	errSegTooLong         = errors.New("segment length too long")
+	errZeroSegLen         = errors.New("zero length segment")
+	errResTooLong         = errors.New("resource length too long")
+	errTooManyQuestions   = errors.New("too many Questions to pack (>65535)")
+	errTooManyAnswers     = errors.New("too many Answers to pack (>65535)")
+	errTooManyAuthorities = errors.New("too many Authorities to pack (>65535)")
+	errTooManyAdditionals = errors.New("too many Additionals to pack (>65535)")
+	errNonCanonicalName   = errors.New("name is not in canonical format (it must end with a .)")
+	errStringTooLong      = errors.New("character string exceeds maximum length (255)")
+	errCompressedSRV      = errors.New("compressed name in SRV resource data")
+)
+
+// Internal constants.
+const (
+	// packStartingCap is the default initial buffer size allocated during
+	// packing.
+	//
+	// The starting capacity doesn't matter too much, but most DNS responses
+	// Will be <= 512 bytes as it is the limit for DNS over UDP.
+	packStartingCap = 512
+
+	// uint16Len is the length (in bytes) of a uint16.
+	uint16Len = 2
+
+	// uint32Len is the length (in bytes) of a uint32.
+	uint32Len = 4
+
+	// headerLen is the length (in bytes) of a DNS header.
+	//
+	// A header is comprised of 6 uint16s and no padding.
+	headerLen = 6 * uint16Len
+)
+
+type nestedError struct {
+	// s is the current level's error message.
+	s string
+
+	// err is the nested error.
+	err error
+}
+
+// nestedError implements error.Error.
+func (e *nestedError) Error() string {
+	return e.s + ": " + e.err.Error()
+}
+
+// Header is a representation of a DNS message header.
+type Header struct {
+	ID                 uint16
+	Response           bool
+	OpCode             OpCode
+	Authoritative      bool
+	Truncated          bool
+	RecursionDesired   bool
+	RecursionAvailable bool
+	RCode              RCode
+}
+
+func (m *Header) pack() (id uint16, bits uint16) {
+	id = m.ID
+	bits = uint16(m.OpCode)<<11 | uint16(m.RCode)
+	if m.RecursionAvailable {
+		bits |= headerBitRA
+	}
+	if m.RecursionDesired {
+		bits |= headerBitRD
+	}
+	if m.Truncated {
+		bits |= headerBitTC
+	}
+	if m.Authoritative {
+		bits |= headerBitAA
+	}
+	if m.Response {
+		bits |= headerBitQR
+	}
+	return
+}
+
+// GoString implements fmt.GoStringer.GoString.
+func (m *Header) GoString() string {
+	return "dnsmessage.Header{" +
+		"ID: " + printUint16(m.ID) + ", " +
+		"Response: " + printBool(m.Response) + ", " +
+		"OpCode: " + m.OpCode.GoString() + ", " +
+		"Authoritative: " + printBool(m.Authoritative) + ", " +
+		"Truncated: " + printBool(m.Truncated) + ", " +
+		"RecursionDesired: " + printBool(m.RecursionDesired) + ", " +
+		"RecursionAvailable: " + printBool(m.RecursionAvailable) + ", " +
+		"RCode: " + m.RCode.GoString() + "}"
+}
+
+// Message is a representation of a DNS message.
+type Message struct {
+	Header
+	Questions   []Question
+	Answers     []Resource
+	Authorities []Resource
+	Additionals []Resource
+}
+
+type section uint8
+
+const (
+	sectionNotStarted section = iota
+	sectionHeader
+	sectionQuestions
+	sectionAnswers
+	sectionAuthorities
+	sectionAdditionals
+	sectionDone
+
+	headerBitQR = 1 << 15 // query/response (response=1)
+	headerBitAA = 1 << 10 // authoritative
+	headerBitTC = 1 << 9  // truncated
+	headerBitRD = 1 << 8  // recursion desired
+	headerBitRA = 1 << 7  // recursion available
+)
+
+var sectionNames = map[section]string{
+	sectionHeader:      "header",
+	sectionQuestions:   "Question",
+	sectionAnswers:     "Answer",
+	sectionAuthorities: "Authority",
+	sectionAdditionals: "Additional",
+}
+
+// header is the wire format for a DNS message header.
+type header struct {
+	id          uint16
+	bits        uint16
+	questions   uint16
+	answers     uint16
+	authorities uint16
+	additionals uint16
+}
+
+func (h *header) count(sec section) uint16 {
+	switch sec {
+	case sectionQuestions:
+		return h.questions
+	case sectionAnswers:
+		return h.answers
+	case sectionAuthorities:
+		return h.authorities
+	case sectionAdditionals:
+		return h.additionals
+	}
+	return 0
+}
+
+// pack appends the wire format of the header to msg.
+func (h *header) pack(msg []byte) []byte {
+	msg = packUint16(msg, h.id)
+	msg = packUint16(msg, h.bits)
+	msg = packUint16(msg, h.questions)
+	msg = packUint16(msg, h.answers)
+	msg = packUint16(msg, h.authorities)
+	return packUint16(msg, h.additionals)
+}
+
+func (h *header) unpack(msg []byte, off int) (int, error) {
+	newOff := off
+	var err error
+	if h.id, newOff, err = unpackUint16(msg, newOff); err != nil {
+		return off, &nestedError{"id", err}
+	}
+	if h.bits, newOff, err = unpackUint16(msg, newOff); err != nil {
+		return off, &nestedError{"bits", err}
+	}
+	if h.questions, newOff, err = unpackUint16(msg, newOff); err != nil {
+		return off, &nestedError{"questions", err}
+	}
+	if h.answers, newOff, err = unpackUint16(msg, newOff); err != nil {
+		return off, &nestedError{"answers", err}
+	}
+	if h.authorities, newOff, err = unpackUint16(msg, newOff); err != nil {
+		return off, &nestedError{"authorities", err}
+	}
+	if h.additionals, newOff, err = unpackUint16(msg, newOff); err != nil {
+		return off, &nestedError{"additionals", err}
+	}
+	return newOff, nil
+}
+
+func (h *header) header() Header {
+	return Header{
+		ID:                 h.id,
+		Response:           (h.bits & headerBitQR) != 0,
+		OpCode:             OpCode(h.bits>>11) & 0xF,
+		Authoritative:      (h.bits & headerBitAA) != 0,
+		Truncated:          (h.bits & headerBitTC) != 0,
+		RecursionDesired:   (h.bits & headerBitRD) != 0,
+		RecursionAvailable: (h.bits & headerBitRA) != 0,
+		RCode:              RCode(h.bits & 0xF),
+	}
+}
+
+// A Resource is a DNS resource record.
+type Resource struct {
+	Header ResourceHeader
+	Body   ResourceBody
+}
+
+func (r *Resource) GoString() string {
+	return "dnsmessage.Resource{" +
+		"Header: " + r.Header.GoString() +
+		", Body: &" + r.Body.GoString() +
+		"}"
+}
+
+// A ResourceBody is a DNS resource record minus the header.
+type ResourceBody interface {
+	// pack packs a Resource except for its header.
+	pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error)
+
+	// realType returns the actual type of the Resource. This is used to
+	// fill in the header Type field.
+	realType() Type
+
+	// GoString implements fmt.GoStringer.GoString.
+	GoString() string
+}
+
+// pack appends the wire format of the Resource to msg.
+func (r *Resource) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
+	if r.Body == nil {
+		return msg, errNilResouceBody
+	}
+	oldMsg := msg
+	r.Header.Type = r.Body.realType()
+	msg, lenOff, err := r.Header.pack(msg, compression, compressionOff)
+	if err != nil {
+		return msg, &nestedError{"ResourceHeader", err}
+	}
+	preLen := len(msg)
+	msg, err = r.Body.pack(msg, compression, compressionOff)
+	if err != nil {
+		return msg, &nestedError{"content", err}
+	}
+	if err := r.Header.fixLen(msg, lenOff, preLen); err != nil {
+		return oldMsg, err
+	}
+	return msg, nil
+}
+
+// A Parser allows incrementally parsing a DNS message.
+//
+// When parsing is started, the Header is parsed. Next, each Question can be
+// either parsed or skipped. Alternatively, all Questions can be skipped at
+// once. When all Questions have been parsed, attempting to parse Questions
+// will return (nil, nil) and attempting to skip Questions will return
+// (true, nil). After all Questions have been either parsed or skipped, all
+// Answers, Authorities and Additionals can be either parsed or skipped in the
+// same way, and each type of Resource must be fully parsed or skipped before
+// proceeding to the next type of Resource.
+//
+// Note that there is no requirement to fully skip or parse the message.
+type Parser struct {
+	msg    []byte
+	header header
+
+	section        section
+	off            int
+	index          int
+	resHeaderValid bool
+	resHeader      ResourceHeader
+}
+
+// Start parses the header and enables the parsing of Questions.
+func (p *Parser) Start(msg []byte) (Header, error) {
+	if p.msg != nil {
+		*p = Parser{}
+	}
+	p.msg = msg
+	var err error
+	if p.off, err = p.header.unpack(msg, 0); err != nil {
+		return Header{}, &nestedError{"unpacking header", err}
+	}
+	p.section = sectionQuestions
+	return p.header.header(), nil
+}
+
+func (p *Parser) checkAdvance(sec section) error {
+	if p.section < sec {
+		return ErrNotStarted
+	}
+	if p.section > sec {
+		return ErrSectionDone
+	}
+	p.resHeaderValid = false
+	if p.index == int(p.header.count(sec)) {
+		p.index = 0
+		p.section++
+		return ErrSectionDone
+	}
+	return nil
+}
+
+func (p *Parser) resource(sec section) (Resource, error) {
+	var r Resource
+	var err error
+	r.Header, err = p.resourceHeader(sec)
+	if err != nil {
+		return r, err
+	}
+	p.resHeaderValid = false
+	r.Body, p.off, err = unpackResourceBody(p.msg, p.off, r.Header)
+	if err != nil {
+		return Resource{}, &nestedError{"unpacking " + sectionNames[sec], err}
+	}
+	p.index++
+	return r, nil
+}
+
+func (p *Parser) resourceHeader(sec section) (ResourceHeader, error) {
+	if p.resHeaderValid {
+		return p.resHeader, nil
+	}
+	if err := p.checkAdvance(sec); err != nil {
+		return ResourceHeader{}, err
+	}
+	var hdr ResourceHeader
+	off, err := hdr.unpack(p.msg, p.off)
+	if err != nil {
+		return ResourceHeader{}, err
+	}
+	p.resHeaderValid = true
+	p.resHeader = hdr
+	p.off = off
+	return hdr, nil
+}
+
+func (p *Parser) skipResource(sec section) error {
+	if p.resHeaderValid {
+		newOff := p.off + int(p.resHeader.Length)
+		if newOff > len(p.msg) {
+			return errResourceLen
+		}
+		p.off = newOff
+		p.resHeaderValid = false
+		p.index++
+		return nil
+	}
+	if err := p.checkAdvance(sec); err != nil {
+		return err
+	}
+	var err error
+	p.off, err = skipResource(p.msg, p.off)
+	if err != nil {
+		return &nestedError{"skipping: " + sectionNames[sec], err}
+	}
+	p.index++
+	return nil
+}
+
+// Question parses a single Question.
+func (p *Parser) Question() (Question, error) {
+	if err := p.checkAdvance(sectionQuestions); err != nil {
+		return Question{}, err
+	}
+	var name Name
+	off, err := name.unpack(p.msg, p.off)
+	if err != nil {
+		return Question{}, &nestedError{"unpacking Question.Name", err}
+	}
+	typ, off, err := unpackType(p.msg, off)
+	if err != nil {
+		return Question{}, &nestedError{"unpacking Question.Type", err}
+	}
+	class, off, err := unpackClass(p.msg, off)
+	if err != nil {
+		return Question{}, &nestedError{"unpacking Question.Class", err}
+	}
+	p.off = off
+	p.index++
+	return Question{name, typ, class}, nil
+}
+
+// AllQuestions parses all Questions.
+func (p *Parser) AllQuestions() ([]Question, error) {
+	// Multiple questions are valid according to the spec,
+	// but servers don't actually support them. There will
+	// be at most one question here.
+	//
+	// Do not pre-allocate based on info in p.header, since
+	// the data is untrusted.
+	qs := []Question{}
+	for {
+		q, err := p.Question()
+		if err == ErrSectionDone {
+			return qs, nil
+		}
+		if err != nil {
+			return nil, err
+		}
+		qs = append(qs, q)
+	}
+}
+
+// SkipQuestion skips a single Question.
+func (p *Parser) SkipQuestion() error {
+	if err := p.checkAdvance(sectionQuestions); err != nil {
+		return err
+	}
+	off, err := skipName(p.msg, p.off)
+	if err != nil {
+		return &nestedError{"skipping Question Name", err}
+	}
+	if off, err = skipType(p.msg, off); err != nil {
+		return &nestedError{"skipping Question Type", err}
+	}
+	if off, err = skipClass(p.msg, off); err != nil {
+		return &nestedError{"skipping Question Class", err}
+	}
+	p.off = off
+	p.index++
+	return nil
+}
+
+// SkipAllQuestions skips all Questions.
+func (p *Parser) SkipAllQuestions() error {
+	for {
+		if err := p.SkipQuestion(); err == ErrSectionDone {
+			return nil
+		} else if err != nil {
+			return err
+		}
+	}
+}
+
+// AnswerHeader parses a single Answer ResourceHeader.
+func (p *Parser) AnswerHeader() (ResourceHeader, error) {
+	return p.resourceHeader(sectionAnswers)
+}
+
+// Answer parses a single Answer Resource.
+func (p *Parser) Answer() (Resource, error) {
+	return p.resource(sectionAnswers)
+}
+
+// AllAnswers parses all Answer Resources.
+func (p *Parser) AllAnswers() ([]Resource, error) {
+	// The most common query is for A/AAAA, which usually returns
+	// a handful of IPs.
+	//
+	// Pre-allocate up to a certain limit, since p.header is
+	// untrusted data.
+	n := int(p.header.answers)
+	if n > 20 {
+		n = 20
+	}
+	as := make([]Resource, 0, n)
+	for {
+		a, err := p.Answer()
+		if err == ErrSectionDone {
+			return as, nil
+		}
+		if err != nil {
+			return nil, err
+		}
+		as = append(as, a)
+	}
+}
+
+// SkipAnswer skips a single Answer Resource.
+func (p *Parser) SkipAnswer() error {
+	return p.skipResource(sectionAnswers)
+}
+
+// SkipAllAnswers skips all Answer Resources.
+func (p *Parser) SkipAllAnswers() error {
+	for {
+		if err := p.SkipAnswer(); err == ErrSectionDone {
+			return nil
+		} else if err != nil {
+			return err
+		}
+	}
+}
+
+// AuthorityHeader parses a single Authority ResourceHeader.
+func (p *Parser) AuthorityHeader() (ResourceHeader, error) {
+	return p.resourceHeader(sectionAuthorities)
+}
+
+// Authority parses a single Authority Resource.
+func (p *Parser) Authority() (Resource, error) {
+	return p.resource(sectionAuthorities)
+}
+
+// AllAuthorities parses all Authority Resources.
+func (p *Parser) AllAuthorities() ([]Resource, error) {
+	// Authorities contains SOA in case of NXDOMAIN and friends,
+	// otherwise it is empty.
+	//
+	// Pre-allocate up to a certain limit, since p.header is
+	// untrusted data.
+	n := int(p.header.authorities)
+	if n > 10 {
+		n = 10
+	}
+	as := make([]Resource, 0, n)
+	for {
+		a, err := p.Authority()
+		if err == ErrSectionDone {
+			return as, nil
+		}
+		if err != nil {
+			return nil, err
+		}
+		as = append(as, a)
+	}
+}
+
+// SkipAuthority skips a single Authority Resource.
+func (p *Parser) SkipAuthority() error {
+	return p.skipResource(sectionAuthorities)
+}
+
+// SkipAllAuthorities skips all Authority Resources.
+func (p *Parser) SkipAllAuthorities() error {
+	for {
+		if err := p.SkipAuthority(); err == ErrSectionDone {
+			return nil
+		} else if err != nil {
+			return err
+		}
+	}
+}
+
+// AdditionalHeader parses a single Additional ResourceHeader.
+func (p *Parser) AdditionalHeader() (ResourceHeader, error) {
+	return p.resourceHeader(sectionAdditionals)
+}
+
+// Additional parses a single Additional Resource.
+func (p *Parser) Additional() (Resource, error) {
+	return p.resource(sectionAdditionals)
+}
+
+// AllAdditionals parses all Additional Resources.
+func (p *Parser) AllAdditionals() ([]Resource, error) {
+	// Additionals usually contain OPT, and sometimes A/AAAA
+	// glue records.
+	//
+	// Pre-allocate up to a certain limit, since p.header is
+	// untrusted data.
+	n := int(p.header.additionals)
+	if n > 10 {
+		n = 10
+	}
+	as := make([]Resource, 0, n)
+	for {
+		a, err := p.Additional()
+		if err == ErrSectionDone {
+			return as, nil
+		}
+		if err != nil {
+			return nil, err
+		}
+		as = append(as, a)
+	}
+}
+
+// SkipAdditional skips a single Additional Resource.
+func (p *Parser) SkipAdditional() error {
+	return p.skipResource(sectionAdditionals)
+}
+
+// SkipAllAdditionals skips all Additional Resources.
+func (p *Parser) SkipAllAdditionals() error {
+	for {
+		if err := p.SkipAdditional(); err == ErrSectionDone {
+			return nil
+		} else if err != nil {
+			return err
+		}
+	}
+}
+
+// CNAMEResource parses a single CNAMEResource.
+//
+// One of the XXXHeader methods must have been called before calling this
+// method.
+func (p *Parser) CNAMEResource() (CNAMEResource, error) {
+	if !p.resHeaderValid || p.resHeader.Type != TypeCNAME {
+		return CNAMEResource{}, ErrNotStarted
+	}
+	r, err := unpackCNAMEResource(p.msg, p.off)
+	if err != nil {
+		return CNAMEResource{}, err
+	}
+	p.off += int(p.resHeader.Length)
+	p.resHeaderValid = false
+	p.index++
+	return r, nil
+}
+
+// MXResource parses a single MXResource.
+//
+// One of the XXXHeader methods must have been called before calling this
+// method.
+func (p *Parser) MXResource() (MXResource, error) {
+	if !p.resHeaderValid || p.resHeader.Type != TypeMX {
+		return MXResource{}, ErrNotStarted
+	}
+	r, err := unpackMXResource(p.msg, p.off)
+	if err != nil {
+		return MXResource{}, err
+	}
+	p.off += int(p.resHeader.Length)
+	p.resHeaderValid = false
+	p.index++
+	return r, nil
+}
+
+// NSResource parses a single NSResource.
+//
+// One of the XXXHeader methods must have been called before calling this
+// method.
+func (p *Parser) NSResource() (NSResource, error) {
+	if !p.resHeaderValid || p.resHeader.Type != TypeNS {
+		return NSResource{}, ErrNotStarted
+	}
+	r, err := unpackNSResource(p.msg, p.off)
+	if err != nil {
+		return NSResource{}, err
+	}
+	p.off += int(p.resHeader.Length)
+	p.resHeaderValid = false
+	p.index++
+	return r, nil
+}
+
+// PTRResource parses a single PTRResource.
+//
+// One of the XXXHeader methods must have been called before calling this
+// method.
+func (p *Parser) PTRResource() (PTRResource, error) {
+	if !p.resHeaderValid || p.resHeader.Type != TypePTR {
+		return PTRResource{}, ErrNotStarted
+	}
+	r, err := unpackPTRResource(p.msg, p.off)
+	if err != nil {
+		return PTRResource{}, err
+	}
+	p.off += int(p.resHeader.Length)
+	p.resHeaderValid = false
+	p.index++
+	return r, nil
+}
+
+// SOAResource parses a single SOAResource.
+//
+// One of the XXXHeader methods must have been called before calling this
+// method.
+func (p *Parser) SOAResource() (SOAResource, error) {
+	if !p.resHeaderValid || p.resHeader.Type != TypeSOA {
+		return SOAResource{}, ErrNotStarted
+	}
+	r, err := unpackSOAResource(p.msg, p.off)
+	if err != nil {
+		return SOAResource{}, err
+	}
+	p.off += int(p.resHeader.Length)
+	p.resHeaderValid = false
+	p.index++
+	return r, nil
+}
+
+// TXTResource parses a single TXTResource.
+//
+// One of the XXXHeader methods must have been called before calling this
+// method.
+func (p *Parser) TXTResource() (TXTResource, error) {
+	if !p.resHeaderValid || p.resHeader.Type != TypeTXT {
+		return TXTResource{}, ErrNotStarted
+	}
+	r, err := unpackTXTResource(p.msg, p.off, p.resHeader.Length)
+	if err != nil {
+		return TXTResource{}, err
+	}
+	p.off += int(p.resHeader.Length)
+	p.resHeaderValid = false
+	p.index++
+	return r, nil
+}
+
+// SRVResource parses a single SRVResource.
+//
+// One of the XXXHeader methods must have been called before calling this
+// method.
+func (p *Parser) SRVResource() (SRVResource, error) {
+	if !p.resHeaderValid || p.resHeader.Type != TypeSRV {
+		return SRVResource{}, ErrNotStarted
+	}
+	r, err := unpackSRVResource(p.msg, p.off)
+	if err != nil {
+		return SRVResource{}, err
+	}
+	p.off += int(p.resHeader.Length)
+	p.resHeaderValid = false
+	p.index++
+	return r, nil
+}
+
+// AResource parses a single AResource.
+//
+// One of the XXXHeader methods must have been called before calling this
+// method.
+func (p *Parser) AResource() (AResource, error) {
+	if !p.resHeaderValid || p.resHeader.Type != TypeA {
+		return AResource{}, ErrNotStarted
+	}
+	r, err := unpackAResource(p.msg, p.off)
+	if err != nil {
+		return AResource{}, err
+	}
+	p.off += int(p.resHeader.Length)
+	p.resHeaderValid = false
+	p.index++
+	return r, nil
+}
+
+// AAAAResource parses a single AAAAResource.
+//
+// One of the XXXHeader methods must have been called before calling this
+// method.
+func (p *Parser) AAAAResource() (AAAAResource, error) {
+	if !p.resHeaderValid || p.resHeader.Type != TypeAAAA {
+		return AAAAResource{}, ErrNotStarted
+	}
+	r, err := unpackAAAAResource(p.msg, p.off)
+	if err != nil {
+		return AAAAResource{}, err
+	}
+	p.off += int(p.resHeader.Length)
+	p.resHeaderValid = false
+	p.index++
+	return r, nil
+}
+
+// OPTResource parses a single OPTResource.
+//
+// One of the XXXHeader methods must have been called before calling this
+// method.
+func (p *Parser) OPTResource() (OPTResource, error) {
+	if !p.resHeaderValid || p.resHeader.Type != TypeOPT {
+		return OPTResource{}, ErrNotStarted
+	}
+	r, err := unpackOPTResource(p.msg, p.off, p.resHeader.Length)
+	if err != nil {
+		return OPTResource{}, err
+	}
+	p.off += int(p.resHeader.Length)
+	p.resHeaderValid = false
+	p.index++
+	return r, nil
+}
+
+// UnknownResource parses a single UnknownResource.
+//
+// One of the XXXHeader methods must have been called before calling this
+// method.
+func (p *Parser) UnknownResource() (UnknownResource, error) {
+	if !p.resHeaderValid {
+		return UnknownResource{}, ErrNotStarted
+	}
+	r, err := unpackUnknownResource(p.resHeader.Type, p.msg, p.off, p.resHeader.Length)
+	if err != nil {
+		return UnknownResource{}, err
+	}
+	p.off += int(p.resHeader.Length)
+	p.resHeaderValid = false
+	p.index++
+	return r, nil
+}
+
+// Unpack parses a full Message.
+func (m *Message) Unpack(msg []byte) error {
+	var p Parser
+	var err error
+	if m.Header, err = p.Start(msg); err != nil {
+		return err
+	}
+	if m.Questions, err = p.AllQuestions(); err != nil {
+		return err
+	}
+	if m.Answers, err = p.AllAnswers(); err != nil {
+		return err
+	}
+	if m.Authorities, err = p.AllAuthorities(); err != nil {
+		return err
+	}
+	if m.Additionals, err = p.AllAdditionals(); err != nil {
+		return err
+	}
+	return nil
+}
+
+// Pack packs a full Message.
+func (m *Message) Pack() ([]byte, error) {
+	return m.AppendPack(make([]byte, 0, packStartingCap))
+}
+
+// AppendPack is like Pack but appends the full Message to b and returns the
+// extended buffer.
+func (m *Message) AppendPack(b []byte) ([]byte, error) {
+	// Validate the lengths. It is very unlikely that anyone will try to
+	// pack more than 65535 of any particular type, but it is possible and
+	// we should fail gracefully.
+	if len(m.Questions) > int(^uint16(0)) {
+		return nil, errTooManyQuestions
+	}
+	if len(m.Answers) > int(^uint16(0)) {
+		return nil, errTooManyAnswers
+	}
+	if len(m.Authorities) > int(^uint16(0)) {
+		return nil, errTooManyAuthorities
+	}
+	if len(m.Additionals) > int(^uint16(0)) {
+		return nil, errTooManyAdditionals
+	}
+
+	var h header
+	h.id, h.bits = m.Header.pack()
+
+	h.questions = uint16(len(m.Questions))
+	h.answers = uint16(len(m.Answers))
+	h.authorities = uint16(len(m.Authorities))
+	h.additionals = uint16(len(m.Additionals))
+
+	compressionOff := len(b)
+	msg := h.pack(b)
+
+	// RFC 1035 allows (but does not require) compression for packing. RFC
+	// 1035 requires unpacking implementations to support compression, so
+	// unconditionally enabling it is fine.
+	//
+	// DNS lookups are typically done over UDP, and RFC 1035 states that UDP
+	// DNS messages can be a maximum of 512 bytes long. Without compression,
+	// many DNS response messages are over this limit, so enabling
+	// compression will help ensure compliance.
+	compression := map[string]int{}
+
+	for i := range m.Questions {
+		var err error
+		if msg, err = m.Questions[i].pack(msg, compression, compressionOff); err != nil {
+			return nil, &nestedError{"packing Question", err}
+		}
+	}
+	for i := range m.Answers {
+		var err error
+		if msg, err = m.Answers[i].pack(msg, compression, compressionOff); err != nil {
+			return nil, &nestedError{"packing Answer", err}
+		}
+	}
+	for i := range m.Authorities {
+		var err error
+		if msg, err = m.Authorities[i].pack(msg, compression, compressionOff); err != nil {
+			return nil, &nestedError{"packing Authority", err}
+		}
+	}
+	for i := range m.Additionals {
+		var err error
+		if msg, err = m.Additionals[i].pack(msg, compression, compressionOff); err != nil {
+			return nil, &nestedError{"packing Additional", err}
+		}
+	}
+
+	return msg, nil
+}
+
+// GoString implements fmt.GoStringer.GoString.
+func (m *Message) GoString() string {
+	s := "dnsmessage.Message{Header: " + m.Header.GoString() + ", " +
+		"Questions: []dnsmessage.Question{"
+	if len(m.Questions) > 0 {
+		s += m.Questions[0].GoString()
+		for _, q := range m.Questions[1:] {
+			s += ", " + q.GoString()
+		}
+	}
+	s += "}, Answers: []dnsmessage.Resource{"
+	if len(m.Answers) > 0 {
+		s += m.Answers[0].GoString()
+		for _, a := range m.Answers[1:] {
+			s += ", " + a.GoString()
+		}
+	}
+	s += "}, Authorities: []dnsmessage.Resource{"
+	if len(m.Authorities) > 0 {
+		s += m.Authorities[0].GoString()
+		for _, a := range m.Authorities[1:] {
+			s += ", " + a.GoString()
+		}
+	}
+	s += "}, Additionals: []dnsmessage.Resource{"
+	if len(m.Additionals) > 0 {
+		s += m.Additionals[0].GoString()
+		for _, a := range m.Additionals[1:] {
+			s += ", " + a.GoString()
+		}
+	}
+	return s + "}}"
+}
+
+// A Builder allows incrementally packing a DNS message.
+//
+// Example usage:
+//
+//	buf := make([]byte, 2, 514)
+//	b := NewBuilder(buf, Header{...})
+//	b.EnableCompression()
+//	// Optionally start a section and add things to that section.
+//	// Repeat adding sections as necessary.
+//	buf, err := b.Finish()
+//	// If err is nil, buf[2:] will contain the built bytes.
+type Builder struct {
+	// msg is the storage for the message being built.
+	msg []byte
+
+	// section keeps track of the current section being built.
+	section section
+
+	// header keeps track of what should go in the header when Finish is
+	// called.
+	header header
+
+	// start is the starting index of the bytes allocated in msg for header.
+	start int
+
+	// compression is a mapping from name suffixes to their starting index
+	// in msg.
+	compression map[string]int
+}
+
+// NewBuilder creates a new builder with compression disabled.
+//
+// Note: Most users will want to immediately enable compression with the
+// EnableCompression method. See that method's comment for why you may or may
+// not want to enable compression.
+//
+// The DNS message is appended to the provided initial buffer buf (which may be
+// nil) as it is built. The final message is returned by the (*Builder).Finish
+// method, which includes buf[:len(buf)] and may return the same underlying
+// array if there was sufficient capacity in the slice.
+func NewBuilder(buf []byte, h Header) Builder {
+	if buf == nil {
+		buf = make([]byte, 0, packStartingCap)
+	}
+	b := Builder{msg: buf, start: len(buf)}
+	b.header.id, b.header.bits = h.pack()
+	var hb [headerLen]byte
+	b.msg = append(b.msg, hb[:]...)
+	b.section = sectionHeader
+	return b
+}
+
+// EnableCompression enables compression in the Builder.
+//
+// Leaving compression disabled avoids compression related allocations, but can
+// result in larger message sizes. Be careful with this mode as it can cause
+// messages to exceed the UDP size limit.
+//
+// According to RFC 1035, section 4.1.4, the use of compression is optional, but
+// all implementations must accept both compressed and uncompressed DNS
+// messages.
+//
+// Compression should be enabled before any sections are added for best results.
+func (b *Builder) EnableCompression() {
+	b.compression = map[string]int{}
+}
+
+func (b *Builder) startCheck(s section) error {
+	if b.section <= sectionNotStarted {
+		return ErrNotStarted
+	}
+	if b.section > s {
+		return ErrSectionDone
+	}
+	return nil
+}
+
+// StartQuestions prepares the builder for packing Questions.
+func (b *Builder) StartQuestions() error {
+	if err := b.startCheck(sectionQuestions); err != nil {
+		return err
+	}
+	b.section = sectionQuestions
+	return nil
+}
+
+// StartAnswers prepares the builder for packing Answers.
+func (b *Builder) StartAnswers() error {
+	if err := b.startCheck(sectionAnswers); err != nil {
+		return err
+	}
+	b.section = sectionAnswers
+	return nil
+}
+
+// StartAuthorities prepares the builder for packing Authorities.
+func (b *Builder) StartAuthorities() error {
+	if err := b.startCheck(sectionAuthorities); err != nil {
+		return err
+	}
+	b.section = sectionAuthorities
+	return nil
+}
+
+// StartAdditionals prepares the builder for packing Additionals.
+func (b *Builder) StartAdditionals() error {
+	if err := b.startCheck(sectionAdditionals); err != nil {
+		return err
+	}
+	b.section = sectionAdditionals
+	return nil
+}
+
+func (b *Builder) incrementSectionCount() error {
+	var count *uint16
+	var err error
+	switch b.section {
+	case sectionQuestions:
+		count = &b.header.questions
+		err = errTooManyQuestions
+	case sectionAnswers:
+		count = &b.header.answers
+		err = errTooManyAnswers
+	case sectionAuthorities:
+		count = &b.header.authorities
+		err = errTooManyAuthorities
+	case sectionAdditionals:
+		count = &b.header.additionals
+		err = errTooManyAdditionals
+	}
+	if *count == ^uint16(0) {
+		return err
+	}
+	*count++
+	return nil
+}
+
+// Question adds a single Question.
+func (b *Builder) Question(q Question) error {
+	if b.section < sectionQuestions {
+		return ErrNotStarted
+	}
+	if b.section > sectionQuestions {
+		return ErrSectionDone
+	}
+	msg, err := q.pack(b.msg, b.compression, b.start)
+	if err != nil {
+		return err
+	}
+	if err := b.incrementSectionCount(); err != nil {
+		return err
+	}
+	b.msg = msg
+	return nil
+}
+
+func (b *Builder) checkResourceSection() error {
+	if b.section < sectionAnswers {
+		return ErrNotStarted
+	}
+	if b.section > sectionAdditionals {
+		return ErrSectionDone
+	}
+	return nil
+}
+
+// CNAMEResource adds a single CNAMEResource.
+func (b *Builder) CNAMEResource(h ResourceHeader, r CNAMEResource) error {
+	if err := b.checkResourceSection(); err != nil {
+		return err
+	}
+	h.Type = r.realType()
+	msg, lenOff, err := h.pack(b.msg, b.compression, b.start)
+	if err != nil {
+		return &nestedError{"ResourceHeader", err}
+	}
+	preLen := len(msg)
+	if msg, err = r.pack(msg, b.compression, b.start); err != nil {
+		return &nestedError{"CNAMEResource body", err}
+	}
+	if err := h.fixLen(msg, lenOff, preLen); err != nil {
+		return err
+	}
+	if err := b.incrementSectionCount(); err != nil {
+		return err
+	}
+	b.msg = msg
+	return nil
+}
+
+// MXResource adds a single MXResource.
+func (b *Builder) MXResource(h ResourceHeader, r MXResource) error {
+	if err := b.checkResourceSection(); err != nil {
+		return err
+	}
+	h.Type = r.realType()
+	msg, lenOff, err := h.pack(b.msg, b.compression, b.start)
+	if err != nil {
+		return &nestedError{"ResourceHeader", err}
+	}
+	preLen := len(msg)
+	if msg, err = r.pack(msg, b.compression, b.start); err != nil {
+		return &nestedError{"MXResource body", err}
+	}
+	if err := h.fixLen(msg, lenOff, preLen); err != nil {
+		return err
+	}
+	if err := b.incrementSectionCount(); err != nil {
+		return err
+	}
+	b.msg = msg
+	return nil
+}
+
+// NSResource adds a single NSResource.
+func (b *Builder) NSResource(h ResourceHeader, r NSResource) error {
+	if err := b.checkResourceSection(); err != nil {
+		return err
+	}
+	h.Type = r.realType()
+	msg, lenOff, err := h.pack(b.msg, b.compression, b.start)
+	if err != nil {
+		return &nestedError{"ResourceHeader", err}
+	}
+	preLen := len(msg)
+	if msg, err = r.pack(msg, b.compression, b.start); err != nil {
+		return &nestedError{"NSResource body", err}
+	}
+	if err := h.fixLen(msg, lenOff, preLen); err != nil {
+		return err
+	}
+	if err := b.incrementSectionCount(); err != nil {
+		return err
+	}
+	b.msg = msg
+	return nil
+}
+
+// PTRResource adds a single PTRResource.
+func (b *Builder) PTRResource(h ResourceHeader, r PTRResource) error {
+	if err := b.checkResourceSection(); err != nil {
+		return err
+	}
+	h.Type = r.realType()
+	msg, lenOff, err := h.pack(b.msg, b.compression, b.start)
+	if err != nil {
+		return &nestedError{"ResourceHeader", err}
+	}
+	preLen := len(msg)
+	if msg, err = r.pack(msg, b.compression, b.start); err != nil {
+		return &nestedError{"PTRResource body", err}
+	}
+	if err := h.fixLen(msg, lenOff, preLen); err != nil {
+		return err
+	}
+	if err := b.incrementSectionCount(); err != nil {
+		return err
+	}
+	b.msg = msg
+	return nil
+}
+
+// SOAResource adds a single SOAResource.
+func (b *Builder) SOAResource(h ResourceHeader, r SOAResource) error {
+	if err := b.checkResourceSection(); err != nil {
+		return err
+	}
+	h.Type = r.realType()
+	msg, lenOff, err := h.pack(b.msg, b.compression, b.start)
+	if err != nil {
+		return &nestedError{"ResourceHeader", err}
+	}
+	preLen := len(msg)
+	if msg, err = r.pack(msg, b.compression, b.start); err != nil {
+		return &nestedError{"SOAResource body", err}
+	}
+	if err := h.fixLen(msg, lenOff, preLen); err != nil {
+		return err
+	}
+	if err := b.incrementSectionCount(); err != nil {
+		return err
+	}
+	b.msg = msg
+	return nil
+}
+
+// TXTResource adds a single TXTResource.
+func (b *Builder) TXTResource(h ResourceHeader, r TXTResource) error {
+	if err := b.checkResourceSection(); err != nil {
+		return err
+	}
+	h.Type = r.realType()
+	msg, lenOff, err := h.pack(b.msg, b.compression, b.start)
+	if err != nil {
+		return &nestedError{"ResourceHeader", err}
+	}
+	preLen := len(msg)
+	if msg, err = r.pack(msg, b.compression, b.start); err != nil {
+		return &nestedError{"TXTResource body", err}
+	}
+	if err := h.fixLen(msg, lenOff, preLen); err != nil {
+		return err
+	}
+	if err := b.incrementSectionCount(); err != nil {
+		return err
+	}
+	b.msg = msg
+	return nil
+}
+
+// SRVResource adds a single SRVResource.
+func (b *Builder) SRVResource(h ResourceHeader, r SRVResource) error {
+	if err := b.checkResourceSection(); err != nil {
+		return err
+	}
+	h.Type = r.realType()
+	msg, lenOff, err := h.pack(b.msg, b.compression, b.start)
+	if err != nil {
+		return &nestedError{"ResourceHeader", err}
+	}
+	preLen := len(msg)
+	if msg, err = r.pack(msg, b.compression, b.start); err != nil {
+		return &nestedError{"SRVResource body", err}
+	}
+	if err := h.fixLen(msg, lenOff, preLen); err != nil {
+		return err
+	}
+	if err := b.incrementSectionCount(); err != nil {
+		return err
+	}
+	b.msg = msg
+	return nil
+}
+
+// AResource adds a single AResource.
+func (b *Builder) AResource(h ResourceHeader, r AResource) error {
+	if err := b.checkResourceSection(); err != nil {
+		return err
+	}
+	h.Type = r.realType()
+	msg, lenOff, err := h.pack(b.msg, b.compression, b.start)
+	if err != nil {
+		return &nestedError{"ResourceHeader", err}
+	}
+	preLen := len(msg)
+	if msg, err = r.pack(msg, b.compression, b.start); err != nil {
+		return &nestedError{"AResource body", err}
+	}
+	if err := h.fixLen(msg, lenOff, preLen); err != nil {
+		return err
+	}
+	if err := b.incrementSectionCount(); err != nil {
+		return err
+	}
+	b.msg = msg
+	return nil
+}
+
+// AAAAResource adds a single AAAAResource.
+func (b *Builder) AAAAResource(h ResourceHeader, r AAAAResource) error {
+	if err := b.checkResourceSection(); err != nil {
+		return err
+	}
+	h.Type = r.realType()
+	msg, lenOff, err := h.pack(b.msg, b.compression, b.start)
+	if err != nil {
+		return &nestedError{"ResourceHeader", err}
+	}
+	preLen := len(msg)
+	if msg, err = r.pack(msg, b.compression, b.start); err != nil {
+		return &nestedError{"AAAAResource body", err}
+	}
+	if err := h.fixLen(msg, lenOff, preLen); err != nil {
+		return err
+	}
+	if err := b.incrementSectionCount(); err != nil {
+		return err
+	}
+	b.msg = msg
+	return nil
+}
+
+// OPTResource adds a single OPTResource.
+func (b *Builder) OPTResource(h ResourceHeader, r OPTResource) error {
+	if err := b.checkResourceSection(); err != nil {
+		return err
+	}
+	h.Type = r.realType()
+	msg, lenOff, err := h.pack(b.msg, b.compression, b.start)
+	if err != nil {
+		return &nestedError{"ResourceHeader", err}
+	}
+	preLen := len(msg)
+	if msg, err = r.pack(msg, b.compression, b.start); err != nil {
+		return &nestedError{"OPTResource body", err}
+	}
+	if err := h.fixLen(msg, lenOff, preLen); err != nil {
+		return err
+	}
+	if err := b.incrementSectionCount(); err != nil {
+		return err
+	}
+	b.msg = msg
+	return nil
+}
+
+// UnknownResource adds a single UnknownResource.
+func (b *Builder) UnknownResource(h ResourceHeader, r UnknownResource) error {
+	if err := b.checkResourceSection(); err != nil {
+		return err
+	}
+	h.Type = r.realType()
+	msg, lenOff, err := h.pack(b.msg, b.compression, b.start)
+	if err != nil {
+		return &nestedError{"ResourceHeader", err}
+	}
+	preLen := len(msg)
+	if msg, err = r.pack(msg, b.compression, b.start); err != nil {
+		return &nestedError{"UnknownResource body", err}
+	}
+	if err := h.fixLen(msg, lenOff, preLen); err != nil {
+		return err
+	}
+	if err := b.incrementSectionCount(); err != nil {
+		return err
+	}
+	b.msg = msg
+	return nil
+}
+
+// Finish ends message building and generates a binary message.
+func (b *Builder) Finish() ([]byte, error) {
+	if b.section < sectionHeader {
+		return nil, ErrNotStarted
+	}
+	b.section = sectionDone
+	// Space for the header was allocated in NewBuilder.
+	b.header.pack(b.msg[b.start:b.start])
+	return b.msg, nil
+}
+
+// A ResourceHeader is the header of a DNS resource record. There are
+// many types of DNS resource records, but they all share the same header.
+type ResourceHeader struct {
+	// Name is the domain name for which this resource record pertains.
+	Name Name
+
+	// Type is the type of DNS resource record.
+	//
+	// This field will be set automatically during packing.
+	Type Type
+
+	// Class is the class of network to which this DNS resource record
+	// pertains.
+	Class Class
+
+	// TTL is the length of time (measured in seconds) which this resource
+	// record is valid for (time to live). All Resources in a set should
+	// have the same TTL (RFC 2181 Section 5.2).
+	TTL uint32
+
+	// Length is the length of data in the resource record after the header.
+	//
+	// This field will be set automatically during packing.
+	Length uint16
+}
+
+// GoString implements fmt.GoStringer.GoString.
+func (h *ResourceHeader) GoString() string {
+	return "dnsmessage.ResourceHeader{" +
+		"Name: " + h.Name.GoString() + ", " +
+		"Type: " + h.Type.GoString() + ", " +
+		"Class: " + h.Class.GoString() + ", " +
+		"TTL: " + printUint32(h.TTL) + ", " +
+		"Length: " + printUint16(h.Length) + "}"
+}
+
+// pack appends the wire format of the ResourceHeader to oldMsg.
+//
+// lenOff is the offset in msg where the Length field was packed.
+func (h *ResourceHeader) pack(oldMsg []byte, compression map[string]int, compressionOff int) (msg []byte, lenOff int, err error) {
+	msg = oldMsg
+	if msg, err = h.Name.pack(msg, compression, compressionOff); err != nil {
+		return oldMsg, 0, &nestedError{"Name", err}
+	}
+	msg = packType(msg, h.Type)
+	msg = packClass(msg, h.Class)
+	msg = packUint32(msg, h.TTL)
+	lenOff = len(msg)
+	msg = packUint16(msg, h.Length)
+	return msg, lenOff, nil
+}
+
+func (h *ResourceHeader) unpack(msg []byte, off int) (int, error) {
+	newOff := off
+	var err error
+	if newOff, err = h.Name.unpack(msg, newOff); err != nil {
+		return off, &nestedError{"Name", err}
+	}
+	if h.Type, newOff, err = unpackType(msg, newOff); err != nil {
+		return off, &nestedError{"Type", err}
+	}
+	if h.Class, newOff, err = unpackClass(msg, newOff); err != nil {
+		return off, &nestedError{"Class", err}
+	}
+	if h.TTL, newOff, err = unpackUint32(msg, newOff); err != nil {
+		return off, &nestedError{"TTL", err}
+	}
+	if h.Length, newOff, err = unpackUint16(msg, newOff); err != nil {
+		return off, &nestedError{"Length", err}
+	}
+	return newOff, nil
+}
+
+// fixLen updates a packed ResourceHeader to include the length of the
+// ResourceBody.
+//
+// lenOff is the offset of the ResourceHeader.Length field in msg.
+//
+// preLen is the length that msg was before the ResourceBody was packed.
+func (h *ResourceHeader) fixLen(msg []byte, lenOff int, preLen int) error {
+	conLen := len(msg) - preLen
+	if conLen > int(^uint16(0)) {
+		return errResTooLong
+	}
+
+	// Fill in the length now that we know how long the content is.
+	packUint16(msg[lenOff:lenOff], uint16(conLen))
+	h.Length = uint16(conLen)
+
+	return nil
+}
+
+// EDNS(0) wire constants.
+const (
+	edns0Version = 0
+
+	edns0DNSSECOK     = 0x00008000
+	ednsVersionMask   = 0x00ff0000
+	edns0DNSSECOKMask = 0x00ff8000
+)
+
+// SetEDNS0 configures h for EDNS(0).
+//
+// The provided extRCode must be an extended RCode.
+func (h *ResourceHeader) SetEDNS0(udpPayloadLen int, extRCode RCode, dnssecOK bool) error {
+	h.Name = Name{Data: [nameLen]byte{'.'}, Length: 1} // RFC 6891 section 6.1.2
+	h.Type = TypeOPT
+	h.Class = Class(udpPayloadLen)
+	h.TTL = uint32(extRCode) >> 4 << 24
+	if dnssecOK {
+		h.TTL |= edns0DNSSECOK
+	}
+	return nil
+}
+
+// DNSSECAllowed reports whether the DNSSEC OK bit is set.
+func (h *ResourceHeader) DNSSECAllowed() bool {
+	return h.TTL&edns0DNSSECOKMask == edns0DNSSECOK // RFC 6891 section 6.1.3
+}
+
+// ExtendedRCode returns an extended RCode.
+//
+// The provided rcode must be the RCode in DNS message header.
+func (h *ResourceHeader) ExtendedRCode(rcode RCode) RCode {
+	if h.TTL&ednsVersionMask == edns0Version { // RFC 6891 section 6.1.3
+		return RCode(h.TTL>>24<<4) | rcode
+	}
+	return rcode
+}
+
+func skipResource(msg []byte, off int) (int, error) {
+	newOff, err := skipName(msg, off)
+	if err != nil {
+		return off, &nestedError{"Name", err}
+	}
+	if newOff, err = skipType(msg, newOff); err != nil {
+		return off, &nestedError{"Type", err}
+	}
+	if newOff, err = skipClass(msg, newOff); err != nil {
+		return off, &nestedError{"Class", err}
+	}
+	if newOff, err = skipUint32(msg, newOff); err != nil {
+		return off, &nestedError{"TTL", err}
+	}
+	length, newOff, err := unpackUint16(msg, newOff)
+	if err != nil {
+		return off, &nestedError{"Length", err}
+	}
+	if newOff += int(length); newOff > len(msg) {
+		return off, errResourceLen
+	}
+	return newOff, nil
+}
+
+// packUint16 appends the wire format of field to msg.
+func packUint16(msg []byte, field uint16) []byte {
+	return append(msg, byte(field>>8), byte(field))
+}
+
+func unpackUint16(msg []byte, off int) (uint16, int, error) {
+	if off+uint16Len > len(msg) {
+		return 0, off, errBaseLen
+	}
+	return uint16(msg[off])<<8 | uint16(msg[off+1]), off + uint16Len, nil
+}
+
+func skipUint16(msg []byte, off int) (int, error) {
+	if off+uint16Len > len(msg) {
+		return off, errBaseLen
+	}
+	return off + uint16Len, nil
+}
+
+// packType appends the wire format of field to msg.
+func packType(msg []byte, field Type) []byte {
+	return packUint16(msg, uint16(field))
+}
+
+func unpackType(msg []byte, off int) (Type, int, error) {
+	t, o, err := unpackUint16(msg, off)
+	return Type(t), o, err
+}
+
+func skipType(msg []byte, off int) (int, error) {
+	return skipUint16(msg, off)
+}
+
+// packClass appends the wire format of field to msg.
+func packClass(msg []byte, field Class) []byte {
+	return packUint16(msg, uint16(field))
+}
+
+func unpackClass(msg []byte, off int) (Class, int, error) {
+	c, o, err := unpackUint16(msg, off)
+	return Class(c), o, err
+}
+
+func skipClass(msg []byte, off int) (int, error) {
+	return skipUint16(msg, off)
+}
+
+// packUint32 appends the wire format of field to msg.
+func packUint32(msg []byte, field uint32) []byte {
+	return append(
+		msg,
+		byte(field>>24),
+		byte(field>>16),
+		byte(field>>8),
+		byte(field),
+	)
+}
+
+func unpackUint32(msg []byte, off int) (uint32, int, error) {
+	if off+uint32Len > len(msg) {
+		return 0, off, errBaseLen
+	}
+	v := uint32(msg[off])<<24 | uint32(msg[off+1])<<16 | uint32(msg[off+2])<<8 | uint32(msg[off+3])
+	return v, off + uint32Len, nil
+}
+
+func skipUint32(msg []byte, off int) (int, error) {
+	if off+uint32Len > len(msg) {
+		return off, errBaseLen
+	}
+	return off + uint32Len, nil
+}
+
+// packText appends the wire format of field to msg.
+func packText(msg []byte, field string) ([]byte, error) {
+	l := len(field)
+	if l > 255 {
+		return nil, errStringTooLong
+	}
+	msg = append(msg, byte(l))
+	msg = append(msg, field...)
+
+	return msg, nil
+}
+
+func unpackText(msg []byte, off int) (string, int, error) {
+	if off >= len(msg) {
+		return "", off, errBaseLen
+	}
+	beginOff := off + 1
+	endOff := beginOff + int(msg[off])
+	if endOff > len(msg) {
+		return "", off, errCalcLen
+	}
+	return string(msg[beginOff:endOff]), endOff, nil
+}
+
+// packBytes appends the wire format of field to msg.
+func packBytes(msg []byte, field []byte) []byte {
+	return append(msg, field...)
+}
+
+func unpackBytes(msg []byte, off int, field []byte) (int, error) {
+	newOff := off + len(field)
+	if newOff > len(msg) {
+		return off, errBaseLen
+	}
+	copy(field, msg[off:newOff])
+	return newOff, nil
+}
+
+const nameLen = 255
+
+// A Name is a non-encoded domain name. It is used instead of strings to avoid
+// allocations.
+type Name struct {
+	Data   [nameLen]byte // 255 bytes
+	Length uint8
+}
+
+// NewName creates a new Name from a string.
+func NewName(name string) (Name, error) {
+	if len([]byte(name)) > nameLen {
+		return Name{}, errCalcLen
+	}
+	n := Name{Length: uint8(len(name))}
+	copy(n.Data[:], []byte(name))
+	return n, nil
+}
+
+// MustNewName creates a new Name from a string and panics on error.
+func MustNewName(name string) Name {
+	n, err := NewName(name)
+	if err != nil {
+		panic("creating name: " + err.Error())
+	}
+	return n
+}
+
+// String implements fmt.Stringer.String.
+func (n Name) String() string {
+	return string(n.Data[:n.Length])
+}
+
+// GoString implements fmt.GoStringer.GoString.
+func (n *Name) GoString() string {
+	return `dnsmessage.MustNewName("` + printString(n.Data[:n.Length]) + `")`
+}
+
+// pack appends the wire format of the Name to msg.
+//
+// Domain names are a sequence of counted strings split at the dots. They end
+// with a zero-length string. Compression can be used to reuse domain suffixes.
+//
+// The compression map will be updated with new domain suffixes. If compression
+// is nil, compression will not be used.
+func (n *Name) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
+	oldMsg := msg
+
+	// Add a trailing dot to canonicalize name.
+	if n.Length == 0 || n.Data[n.Length-1] != '.' {
+		return oldMsg, errNonCanonicalName
+	}
+
+	// Allow root domain.
+	if n.Data[0] == '.' && n.Length == 1 {
+		return append(msg, 0), nil
+	}
+
+	// Emit sequence of counted strings, chopping at dots.
+	for i, begin := 0, 0; i < int(n.Length); i++ {
+		// Check for the end of the segment.
+		if n.Data[i] == '.' {
+			// The two most significant bits have special meaning.
+			// It isn't allowed for segments to be long enough to
+			// need them.
+			if i-begin >= 1<<6 {
+				return oldMsg, errSegTooLong
+			}
+
+			// Segments must have a non-zero length.
+			if i-begin == 0 {
+				return oldMsg, errZeroSegLen
+			}
+
+			msg = append(msg, byte(i-begin))
+
+			for j := begin; j < i; j++ {
+				msg = append(msg, n.Data[j])
+			}
+
+			begin = i + 1
+			continue
+		}
+
+		// We can only compress domain suffixes starting with a new
+		// segment. A pointer is two bytes with the two most significant
+		// bits set to 1 to indicate that it is a pointer.
+		if (i == 0 || n.Data[i-1] == '.') && compression != nil {
+			if ptr, ok := compression[string(n.Data[i:])]; ok {
+				// Hit. Emit a pointer instead of the rest of
+				// the domain.
+				return append(msg, byte(ptr>>8|0xC0), byte(ptr)), nil
+			}
+
+			// Miss. Add the suffix to the compression table if the
+			// offset can be stored in the available 14 bytes.
+			if len(msg) <= int(^uint16(0)>>2) {
+				compression[string(n.Data[i:])] = len(msg) - compressionOff
+			}
+		}
+	}
+	return append(msg, 0), nil
+}
+
+// unpack unpacks a domain name.
+func (n *Name) unpack(msg []byte, off int) (int, error) {
+	return n.unpackCompressed(msg, off, true /* allowCompression */)
+}
+
+func (n *Name) unpackCompressed(msg []byte, off int, allowCompression bool) (int, error) {
+	// currOff is the current working offset.
+	currOff := off
+
+	// newOff is the offset where the next record will start. Pointers lead
+	// to data that belongs to other names and thus doesn't count towards to
+	// the usage of this name.
+	newOff := off
+
+	// ptr is the number of pointers followed.
+	var ptr int
+
+	// Name is a slice representation of the name data.
+	name := n.Data[:0]
+
+Loop:
+	for {
+		if currOff >= len(msg) {
+			return off, errBaseLen
+		}
+		c := int(msg[currOff])
+		currOff++
+		switch c & 0xC0 {
+		case 0x00: // String segment
+			if c == 0x00 {
+				// A zero length signals the end of the name.
+				break Loop
+			}
+			endOff := currOff + c
+			if endOff > len(msg) {
+				return off, errCalcLen
+			}
+			name = append(name, msg[currOff:endOff]...)
+			name = append(name, '.')
+			currOff = endOff
+		case 0xC0: // Pointer
+			if !allowCompression {
+				return off, errCompressedSRV
+			}
+			if currOff >= len(msg) {
+				return off, errInvalidPtr
+			}
+			c1 := msg[currOff]
+			currOff++
+			if ptr == 0 {
+				newOff = currOff
+			}
+			// Don't follow too many pointers, maybe there's a loop.
+			if ptr++; ptr > 10 {
+				return off, errTooManyPtr
+			}
+			currOff = (c^0xC0)<<8 | int(c1)
+		default:
+			// Prefixes 0x80 and 0x40 are reserved.
+			return off, errReserved
+		}
+	}
+	if len(name) == 0 {
+		name = append(name, '.')
+	}
+	if len(name) > len(n.Data) {
+		return off, errCalcLen
+	}
+	n.Length = uint8(len(name))
+	if ptr == 0 {
+		newOff = currOff
+	}
+	return newOff, nil
+}
+
+func skipName(msg []byte, off int) (int, error) {
+	// newOff is the offset where the next record will start. Pointers lead
+	// to data that belongs to other names and thus doesn't count towards to
+	// the usage of this name.
+	newOff := off
+
+Loop:
+	for {
+		if newOff >= len(msg) {
+			return off, errBaseLen
+		}
+		c := int(msg[newOff])
+		newOff++
+		switch c & 0xC0 {
+		case 0x00:
+			if c == 0x00 {
+				// A zero length signals the end of the name.
+				break Loop
+			}
+			// literal string
+			newOff += c
+			if newOff > len(msg) {
+				return off, errCalcLen
+			}
+		case 0xC0:
+			// Pointer to somewhere else in msg.
+
+			// Pointers are two bytes.
+			newOff++
+
+			// Don't follow the pointer as the data here has ended.
+			break Loop
+		default:
+			// Prefixes 0x80 and 0x40 are reserved.
+			return off, errReserved
+		}
+	}
+
+	return newOff, nil
+}
+
+// A Question is a DNS query.
+type Question struct {
+	Name  Name
+	Type  Type
+	Class Class
+}
+
+// pack appends the wire format of the Question to msg.
+func (q *Question) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
+	msg, err := q.Name.pack(msg, compression, compressionOff)
+	if err != nil {
+		return msg, &nestedError{"Name", err}
+	}
+	msg = packType(msg, q.Type)
+	return packClass(msg, q.Class), nil
+}
+
+// GoString implements fmt.GoStringer.GoString.
+func (q *Question) GoString() string {
+	return "dnsmessage.Question{" +
+		"Name: " + q.Name.GoString() + ", " +
+		"Type: " + q.Type.GoString() + ", " +
+		"Class: " + q.Class.GoString() + "}"
+}
+
+func unpackResourceBody(msg []byte, off int, hdr ResourceHeader) (ResourceBody, int, error) {
+	var (
+		r    ResourceBody
+		err  error
+		name string
+	)
+	switch hdr.Type {
+	case TypeA:
+		var rb AResource
+		rb, err = unpackAResource(msg, off)
+		r = &rb
+		name = "A"
+	case TypeNS:
+		var rb NSResource
+		rb, err = unpackNSResource(msg, off)
+		r = &rb
+		name = "NS"
+	case TypeCNAME:
+		var rb CNAMEResource
+		rb, err = unpackCNAMEResource(msg, off)
+		r = &rb
+		name = "CNAME"
+	case TypeSOA:
+		var rb SOAResource
+		rb, err = unpackSOAResource(msg, off)
+		r = &rb
+		name = "SOA"
+	case TypePTR:
+		var rb PTRResource
+		rb, err = unpackPTRResource(msg, off)
+		r = &rb
+		name = "PTR"
+	case TypeMX:
+		var rb MXResource
+		rb, err = unpackMXResource(msg, off)
+		r = &rb
+		name = "MX"
+	case TypeTXT:
+		var rb TXTResource
+		rb, err = unpackTXTResource(msg, off, hdr.Length)
+		r = &rb
+		name = "TXT"
+	case TypeAAAA:
+		var rb AAAAResource
+		rb, err = unpackAAAAResource(msg, off)
+		r = &rb
+		name = "AAAA"
+	case TypeSRV:
+		var rb SRVResource
+		rb, err = unpackSRVResource(msg, off)
+		r = &rb
+		name = "SRV"
+	case TypeOPT:
+		var rb OPTResource
+		rb, err = unpackOPTResource(msg, off, hdr.Length)
+		r = &rb
+		name = "OPT"
+	default:
+		var rb UnknownResource
+		rb, err = unpackUnknownResource(hdr.Type, msg, off, hdr.Length)
+		r = &rb
+		name = "Unknown"
+	}
+	if err != nil {
+		return nil, off, &nestedError{name + " record", err}
+	}
+	return r, off + int(hdr.Length), nil
+}
+
+// A CNAMEResource is a CNAME Resource record.
+type CNAMEResource struct {
+	CNAME Name
+}
+
+func (r *CNAMEResource) realType() Type {
+	return TypeCNAME
+}
+
+// pack appends the wire format of the CNAMEResource to msg.
+func (r *CNAMEResource) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
+	return r.CNAME.pack(msg, compression, compressionOff)
+}
+
+// GoString implements fmt.GoStringer.GoString.
+func (r *CNAMEResource) GoString() string {
+	return "dnsmessage.CNAMEResource{CNAME: " + r.CNAME.GoString() + "}"
+}
+
+func unpackCNAMEResource(msg []byte, off int) (CNAMEResource, error) {
+	var cname Name
+	if _, err := cname.unpack(msg, off); err != nil {
+		return CNAMEResource{}, err
+	}
+	return CNAMEResource{cname}, nil
+}
+
+// An MXResource is an MX Resource record.
+type MXResource struct {
+	Pref uint16
+	MX   Name
+}
+
+func (r *MXResource) realType() Type {
+	return TypeMX
+}
+
+// pack appends the wire format of the MXResource to msg.
+func (r *MXResource) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
+	oldMsg := msg
+	msg = packUint16(msg, r.Pref)
+	msg, err := r.MX.pack(msg, compression, compressionOff)
+	if err != nil {
+		return oldMsg, &nestedError{"MXResource.MX", err}
+	}
+	return msg, nil
+}
+
+// GoString implements fmt.GoStringer.GoString.
+func (r *MXResource) GoString() string {
+	return "dnsmessage.MXResource{" +
+		"Pref: " + printUint16(r.Pref) + ", " +
+		"MX: " + r.MX.GoString() + "}"
+}
+
+func unpackMXResource(msg []byte, off int) (MXResource, error) {
+	pref, off, err := unpackUint16(msg, off)
+	if err != nil {
+		return MXResource{}, &nestedError{"Pref", err}
+	}
+	var mx Name
+	if _, err := mx.unpack(msg, off); err != nil {
+		return MXResource{}, &nestedError{"MX", err}
+	}
+	return MXResource{pref, mx}, nil
+}
+
+// An NSResource is an NS Resource record.
+type NSResource struct {
+	NS Name
+}
+
+func (r *NSResource) realType() Type {
+	return TypeNS
+}
+
+// pack appends the wire format of the NSResource to msg.
+func (r *NSResource) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
+	return r.NS.pack(msg, compression, compressionOff)
+}
+
+// GoString implements fmt.GoStringer.GoString.
+func (r *NSResource) GoString() string {
+	return "dnsmessage.NSResource{NS: " + r.NS.GoString() + "}"
+}
+
+func unpackNSResource(msg []byte, off int) (NSResource, error) {
+	var ns Name
+	if _, err := ns.unpack(msg, off); err != nil {
+		return NSResource{}, err
+	}
+	return NSResource{ns}, nil
+}
+
+// A PTRResource is a PTR Resource record.
+type PTRResource struct {
+	PTR Name
+}
+
+func (r *PTRResource) realType() Type {
+	return TypePTR
+}
+
+// pack appends the wire format of the PTRResource to msg.
+func (r *PTRResource) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
+	return r.PTR.pack(msg, compression, compressionOff)
+}
+
+// GoString implements fmt.GoStringer.GoString.
+func (r *PTRResource) GoString() string {
+	return "dnsmessage.PTRResource{PTR: " + r.PTR.GoString() + "}"
+}
+
+func unpackPTRResource(msg []byte, off int) (PTRResource, error) {
+	var ptr Name
+	if _, err := ptr.unpack(msg, off); err != nil {
+		return PTRResource{}, err
+	}
+	return PTRResource{ptr}, nil
+}
+
+// An SOAResource is an SOA Resource record.
+type SOAResource struct {
+	NS      Name
+	MBox    Name
+	Serial  uint32
+	Refresh uint32
+	Retry   uint32
+	Expire  uint32
+
+	// MinTTL the is the default TTL of Resources records which did not
+	// contain a TTL value and the TTL of negative responses. (RFC 2308
+	// Section 4)
+	MinTTL uint32
+}
+
+func (r *SOAResource) realType() Type {
+	return TypeSOA
+}
+
+// pack appends the wire format of the SOAResource to msg.
+func (r *SOAResource) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
+	oldMsg := msg
+	msg, err := r.NS.pack(msg, compression, compressionOff)
+	if err != nil {
+		return oldMsg, &nestedError{"SOAResource.NS", err}
+	}
+	msg, err = r.MBox.pack(msg, compression, compressionOff)
+	if err != nil {
+		return oldMsg, &nestedError{"SOAResource.MBox", err}
+	}
+	msg = packUint32(msg, r.Serial)
+	msg = packUint32(msg, r.Refresh)
+	msg = packUint32(msg, r.Retry)
+	msg = packUint32(msg, r.Expire)
+	return packUint32(msg, r.MinTTL), nil
+}
+
+// GoString implements fmt.GoStringer.GoString.
+func (r *SOAResource) GoString() string {
+	return "dnsmessage.SOAResource{" +
+		"NS: " + r.NS.GoString() + ", " +
+		"MBox: " + r.MBox.GoString() + ", " +
+		"Serial: " + printUint32(r.Serial) + ", " +
+		"Refresh: " + printUint32(r.Refresh) + ", " +
+		"Retry: " + printUint32(r.Retry) + ", " +
+		"Expire: " + printUint32(r.Expire) + ", " +
+		"MinTTL: " + printUint32(r.MinTTL) + "}"
+}
+
+func unpackSOAResource(msg []byte, off int) (SOAResource, error) {
+	var ns Name
+	off, err := ns.unpack(msg, off)
+	if err != nil {
+		return SOAResource{}, &nestedError{"NS", err}
+	}
+	var mbox Name
+	if off, err = mbox.unpack(msg, off); err != nil {
+		return SOAResource{}, &nestedError{"MBox", err}
+	}
+	serial, off, err := unpackUint32(msg, off)
+	if err != nil {
+		return SOAResource{}, &nestedError{"Serial", err}
+	}
+	refresh, off, err := unpackUint32(msg, off)
+	if err != nil {
+		return SOAResource{}, &nestedError{"Refresh", err}
+	}
+	retry, off, err := unpackUint32(msg, off)
+	if err != nil {
+		return SOAResource{}, &nestedError{"Retry", err}
+	}
+	expire, off, err := unpackUint32(msg, off)
+	if err != nil {
+		return SOAResource{}, &nestedError{"Expire", err}
+	}
+	minTTL, _, err := unpackUint32(msg, off)
+	if err != nil {
+		return SOAResource{}, &nestedError{"MinTTL", err}
+	}
+	return SOAResource{ns, mbox, serial, refresh, retry, expire, minTTL}, nil
+}
+
+// A TXTResource is a TXT Resource record.
+type TXTResource struct {
+	TXT []string
+}
+
+func (r *TXTResource) realType() Type {
+	return TypeTXT
+}
+
+// pack appends the wire format of the TXTResource to msg.
+func (r *TXTResource) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
+	oldMsg := msg
+	for _, s := range r.TXT {
+		var err error
+		msg, err = packText(msg, s)
+		if err != nil {
+			return oldMsg, err
+		}
+	}
+	return msg, nil
+}
+
+// GoString implements fmt.GoStringer.GoString.
+func (r *TXTResource) GoString() string {
+	s := "dnsmessage.TXTResource{TXT: []string{"
+	if len(r.TXT) == 0 {
+		return s + "}}"
+	}
+	s += `"` + printString([]byte(r.TXT[0]))
+	for _, t := range r.TXT[1:] {
+		s += `", "` + printString([]byte(t))
+	}
+	return s + `"}}`
+}
+
+func unpackTXTResource(msg []byte, off int, length uint16) (TXTResource, error) {
+	txts := make([]string, 0, 1)
+	for n := uint16(0); n < length; {
+		var t string
+		var err error
+		if t, off, err = unpackText(msg, off); err != nil {
+			return TXTResource{}, &nestedError{"text", err}
+		}
+		// Check if we got too many bytes.
+		if length-n < uint16(len(t))+1 {
+			return TXTResource{}, errCalcLen
+		}
+		n += uint16(len(t)) + 1
+		txts = append(txts, t)
+	}
+	return TXTResource{txts}, nil
+}
+
+// An SRVResource is an SRV Resource record.
+type SRVResource struct {
+	Priority uint16
+	Weight   uint16
+	Port     uint16
+	Target   Name // Not compressed as per RFC 2782.
+}
+
+func (r *SRVResource) realType() Type {
+	return TypeSRV
+}
+
+// pack appends the wire format of the SRVResource to msg.
+func (r *SRVResource) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
+	oldMsg := msg
+	msg = packUint16(msg, r.Priority)
+	msg = packUint16(msg, r.Weight)
+	msg = packUint16(msg, r.Port)
+	msg, err := r.Target.pack(msg, nil, compressionOff)
+	if err != nil {
+		return oldMsg, &nestedError{"SRVResource.Target", err}
+	}
+	return msg, nil
+}
+
+// GoString implements fmt.GoStringer.GoString.
+func (r *SRVResource) GoString() string {
+	return "dnsmessage.SRVResource{" +
+		"Priority: " + printUint16(r.Priority) + ", " +
+		"Weight: " + printUint16(r.Weight) + ", " +
+		"Port: " + printUint16(r.Port) + ", " +
+		"Target: " + r.Target.GoString() + "}"
+}
+
+func unpackSRVResource(msg []byte, off int) (SRVResource, error) {
+	priority, off, err := unpackUint16(msg, off)
+	if err != nil {
+		return SRVResource{}, &nestedError{"Priority", err}
+	}
+	weight, off, err := unpackUint16(msg, off)
+	if err != nil {
+		return SRVResource{}, &nestedError{"Weight", err}
+	}
+	port, off, err := unpackUint16(msg, off)
+	if err != nil {
+		return SRVResource{}, &nestedError{"Port", err}
+	}
+	var target Name
+	if _, err := target.unpackCompressed(msg, off, false /* allowCompression */); err != nil {
+		return SRVResource{}, &nestedError{"Target", err}
+	}
+	return SRVResource{priority, weight, port, target}, nil
+}
+
+// An AResource is an A Resource record.
+type AResource struct {
+	A [4]byte
+}
+
+func (r *AResource) realType() Type {
+	return TypeA
+}
+
+// pack appends the wire format of the AResource to msg.
+func (r *AResource) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
+	return packBytes(msg, r.A[:]), nil
+}
+
+// GoString implements fmt.GoStringer.GoString.
+func (r *AResource) GoString() string {
+	return "dnsmessage.AResource{" +
+		"A: [4]byte{" + printByteSlice(r.A[:]) + "}}"
+}
+
+func unpackAResource(msg []byte, off int) (AResource, error) {
+	var a [4]byte
+	if _, err := unpackBytes(msg, off, a[:]); err != nil {
+		return AResource{}, err
+	}
+	return AResource{a}, nil
+}
+
+// An AAAAResource is an AAAA Resource record.
+type AAAAResource struct {
+	AAAA [16]byte
+}
+
+func (r *AAAAResource) realType() Type {
+	return TypeAAAA
+}
+
+// GoString implements fmt.GoStringer.GoString.
+func (r *AAAAResource) GoString() string {
+	return "dnsmessage.AAAAResource{" +
+		"AAAA: [16]byte{" + printByteSlice(r.AAAA[:]) + "}}"
+}
+
+// pack appends the wire format of the AAAAResource to msg.
+func (r *AAAAResource) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
+	return packBytes(msg, r.AAAA[:]), nil
+}
+
+func unpackAAAAResource(msg []byte, off int) (AAAAResource, error) {
+	var aaaa [16]byte
+	if _, err := unpackBytes(msg, off, aaaa[:]); err != nil {
+		return AAAAResource{}, err
+	}
+	return AAAAResource{aaaa}, nil
+}
+
+// An OPTResource is an OPT pseudo Resource record.
+//
+// The pseudo resource record is part of the extension mechanisms for DNS
+// as defined in RFC 6891.
+type OPTResource struct {
+	Options []Option
+}
+
+// An Option represents a DNS message option within OPTResource.
+//
+// The message option is part of the extension mechanisms for DNS as
+// defined in RFC 6891.
+type Option struct {
+	Code uint16 // option code
+	Data []byte
+}
+
+// GoString implements fmt.GoStringer.GoString.
+func (o *Option) GoString() string {
+	return "dnsmessage.Option{" +
+		"Code: " + printUint16(o.Code) + ", " +
+		"Data: []byte{" + printByteSlice(o.Data) + "}}"
+}
+
+func (r *OPTResource) realType() Type {
+	return TypeOPT
+}
+
+func (r *OPTResource) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
+	for _, opt := range r.Options {
+		msg = packUint16(msg, opt.Code)
+		l := uint16(len(opt.Data))
+		msg = packUint16(msg, l)
+		msg = packBytes(msg, opt.Data)
+	}
+	return msg, nil
+}
+
+// GoString implements fmt.GoStringer.GoString.
+func (r *OPTResource) GoString() string {
+	s := "dnsmessage.OPTResource{Options: []dnsmessage.Option{"
+	if len(r.Options) == 0 {
+		return s + "}}"
+	}
+	s += r.Options[0].GoString()
+	for _, o := range r.Options[1:] {
+		s += ", " + o.GoString()
+	}
+	return s + "}}"
+}
+
+func unpackOPTResource(msg []byte, off int, length uint16) (OPTResource, error) {
+	var opts []Option
+	for oldOff := off; off < oldOff+int(length); {
+		var err error
+		var o Option
+		o.Code, off, err = unpackUint16(msg, off)
+		if err != nil {
+			return OPTResource{}, &nestedError{"Code", err}
+		}
+		var l uint16
+		l, off, err = unpackUint16(msg, off)
+		if err != nil {
+			return OPTResource{}, &nestedError{"Data", err}
+		}
+		o.Data = make([]byte, l)
+		if copy(o.Data, msg[off:]) != int(l) {
+			return OPTResource{}, &nestedError{"Data", errCalcLen}
+		}
+		off += int(l)
+		opts = append(opts, o)
+	}
+	return OPTResource{opts}, nil
+}
+
+// An UnknownResource is a catch-all container for unknown record types.
+type UnknownResource struct {
+	Type Type
+	Data []byte
+}
+
+func (r *UnknownResource) realType() Type {
+	return r.Type
+}
+
+// pack appends the wire format of the UnknownResource to msg.
+func (r *UnknownResource) pack(msg []byte, compression map[string]int, compressionOff int) ([]byte, error) {
+	return packBytes(msg, r.Data[:]), nil
+}
+
+// GoString implements fmt.GoStringer.GoString.
+func (r *UnknownResource) GoString() string {
+	return "dnsmessage.UnknownResource{" +
+		"Type: " + r.Type.GoString() + ", " +
+		"Data: []byte{" + printByteSlice(r.Data) + "}}"
+}
+
+func unpackUnknownResource(recordType Type, msg []byte, off int, length uint16) (UnknownResource, error) {
+	parsed := UnknownResource{
+		Type: recordType,
+		Data: make([]byte, length),
+	}
+	if _, err := unpackBytes(msg, off, parsed.Data); err != nil {
+		return UnknownResource{}, err
+	}
+	return parsed, nil
+}
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/http/httpguts/guts.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/http/httpguts/guts.go
index e6cd0ced39..e6cd0ced39 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/http/httpguts/guts.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/http/httpguts/guts.go
diff --git a/contrib/go/_std_1.19/src/vendor/golang.org/x/net/http/httpguts/httplex.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/http/httpguts/httplex.go
new file mode 100644
index 0000000000..6e071e8524
--- /dev/null
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/http/httpguts/httplex.go
@@ -0,0 +1,352 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package httpguts
+
+import (
+	"net"
+	"strings"
+	"unicode/utf8"
+
+	"golang.org/x/net/idna"
+)
+
+var isTokenTable = [127]bool{
+	'!':  true,
+	'#':  true,
+	'$':  true,
+	'%':  true,
+	'&':  true,
+	'\'': true,
+	'*':  true,
+	'+':  true,
+	'-':  true,
+	'.':  true,
+	'0':  true,
+	'1':  true,
+	'2':  true,
+	'3':  true,
+	'4':  true,
+	'5':  true,
+	'6':  true,
+	'7':  true,
+	'8':  true,
+	'9':  true,
+	'A':  true,
+	'B':  true,
+	'C':  true,
+	'D':  true,
+	'E':  true,
+	'F':  true,
+	'G':  true,
+	'H':  true,
+	'I':  true,
+	'J':  true,
+	'K':  true,
+	'L':  true,
+	'M':  true,
+	'N':  true,
+	'O':  true,
+	'P':  true,
+	'Q':  true,
+	'R':  true,
+	'S':  true,
+	'T':  true,
+	'U':  true,
+	'W':  true,
+	'V':  true,
+	'X':  true,
+	'Y':  true,
+	'Z':  true,
+	'^':  true,
+	'_':  true,
+	'`':  true,
+	'a':  true,
+	'b':  true,
+	'c':  true,
+	'd':  true,
+	'e':  true,
+	'f':  true,
+	'g':  true,
+	'h':  true,
+	'i':  true,
+	'j':  true,
+	'k':  true,
+	'l':  true,
+	'm':  true,
+	'n':  true,
+	'o':  true,
+	'p':  true,
+	'q':  true,
+	'r':  true,
+	's':  true,
+	't':  true,
+	'u':  true,
+	'v':  true,
+	'w':  true,
+	'x':  true,
+	'y':  true,
+	'z':  true,
+	'|':  true,
+	'~':  true,
+}
+
+func IsTokenRune(r rune) bool {
+	i := int(r)
+	return i < len(isTokenTable) && isTokenTable[i]
+}
+
+func isNotToken(r rune) bool {
+	return !IsTokenRune(r)
+}
+
+// HeaderValuesContainsToken reports whether any string in values
+// contains the provided token, ASCII case-insensitively.
+func HeaderValuesContainsToken(values []string, token string) bool {
+	for _, v := range values {
+		if headerValueContainsToken(v, token) {
+			return true
+		}
+	}
+	return false
+}
+
+// isOWS reports whether b is an optional whitespace byte, as defined
+// by RFC 7230 section 3.2.3.
+func isOWS(b byte) bool { return b == ' ' || b == '\t' }
+
+// trimOWS returns x with all optional whitespace removes from the
+// beginning and end.
+func trimOWS(x string) string {
+	// TODO: consider using strings.Trim(x, " \t") instead,
+	// if and when it's fast enough. See issue 10292.
+	// But this ASCII-only code will probably always beat UTF-8
+	// aware code.
+	for len(x) > 0 && isOWS(x[0]) {
+		x = x[1:]
+	}
+	for len(x) > 0 && isOWS(x[len(x)-1]) {
+		x = x[:len(x)-1]
+	}
+	return x
+}
+
+// headerValueContainsToken reports whether v (assumed to be a
+// 0#element, in the ABNF extension described in RFC 7230 section 7)
+// contains token amongst its comma-separated tokens, ASCII
+// case-insensitively.
+func headerValueContainsToken(v string, token string) bool {
+	for comma := strings.IndexByte(v, ','); comma != -1; comma = strings.IndexByte(v, ',') {
+		if tokenEqual(trimOWS(v[:comma]), token) {
+			return true
+		}
+		v = v[comma+1:]
+	}
+	return tokenEqual(trimOWS(v), token)
+}
+
+// lowerASCII returns the ASCII lowercase version of b.
+func lowerASCII(b byte) byte {
+	if 'A' <= b && b <= 'Z' {
+		return b + ('a' - 'A')
+	}
+	return b
+}
+
+// tokenEqual reports whether t1 and t2 are equal, ASCII case-insensitively.
+func tokenEqual(t1, t2 string) bool {
+	if len(t1) != len(t2) {
+		return false
+	}
+	for i, b := range t1 {
+		if b >= utf8.RuneSelf {
+			// No UTF-8 or non-ASCII allowed in tokens.
+			return false
+		}
+		if lowerASCII(byte(b)) != lowerASCII(t2[i]) {
+			return false
+		}
+	}
+	return true
+}
+
+// isLWS reports whether b is linear white space, according
+// to http://www.w3.org/Protocols/rfc2616/rfc2616-sec2.html#sec2.2
+//
+//	LWS            = [CRLF] 1*( SP | HT )
+func isLWS(b byte) bool { return b == ' ' || b == '\t' }
+
+// isCTL reports whether b is a control byte, according
+// to http://www.w3.org/Protocols/rfc2616/rfc2616-sec2.html#sec2.2
+//
+//	CTL            = <any US-ASCII control character
+//	                 (octets 0 - 31) and DEL (127)>
+func isCTL(b byte) bool {
+	const del = 0x7f // a CTL
+	return b < ' ' || b == del
+}
+
+// ValidHeaderFieldName reports whether v is a valid HTTP/1.x header name.
+// HTTP/2 imposes the additional restriction that uppercase ASCII
+// letters are not allowed.
+//
+// RFC 7230 says:
+//
+//	header-field   = field-name ":" OWS field-value OWS
+//	field-name     = token
+//	token          = 1*tchar
+//	tchar = "!" / "#" / "$" / "%" / "&" / "'" / "*" / "+" / "-" / "." /
+//	        "^" / "_" / "`" / "|" / "~" / DIGIT / ALPHA
+func ValidHeaderFieldName(v string) bool {
+	if len(v) == 0 {
+		return false
+	}
+	for _, r := range v {
+		if !IsTokenRune(r) {
+			return false
+		}
+	}
+	return true
+}
+
+// ValidHostHeader reports whether h is a valid host header.
+func ValidHostHeader(h string) bool {
+	// The latest spec is actually this:
+	//
+	// http://tools.ietf.org/html/rfc7230#section-5.4
+	//     Host = uri-host [ ":" port ]
+	//
+	// Where uri-host is:
+	//     http://tools.ietf.org/html/rfc3986#section-3.2.2
+	//
+	// But we're going to be much more lenient for now and just
+	// search for any byte that's not a valid byte in any of those
+	// expressions.
+	for i := 0; i < len(h); i++ {
+		if !validHostByte[h[i]] {
+			return false
+		}
+	}
+	return true
+}
+
+// See the validHostHeader comment.
+var validHostByte = [256]bool{
+	'0': true, '1': true, '2': true, '3': true, '4': true, '5': true, '6': true, '7': true,
+	'8': true, '9': true,
+
+	'a': true, 'b': true, 'c': true, 'd': true, 'e': true, 'f': true, 'g': true, 'h': true,
+	'i': true, 'j': true, 'k': true, 'l': true, 'm': true, 'n': true, 'o': true, 'p': true,
+	'q': true, 'r': true, 's': true, 't': true, 'u': true, 'v': true, 'w': true, 'x': true,
+	'y': true, 'z': true,
+
+	'A': true, 'B': true, 'C': true, 'D': true, 'E': true, 'F': true, 'G': true, 'H': true,
+	'I': true, 'J': true, 'K': true, 'L': true, 'M': true, 'N': true, 'O': true, 'P': true,
+	'Q': true, 'R': true, 'S': true, 'T': true, 'U': true, 'V': true, 'W': true, 'X': true,
+	'Y': true, 'Z': true,
+
+	'!':  true, // sub-delims
+	'$':  true, // sub-delims
+	'%':  true, // pct-encoded (and used in IPv6 zones)
+	'&':  true, // sub-delims
+	'(':  true, // sub-delims
+	')':  true, // sub-delims
+	'*':  true, // sub-delims
+	'+':  true, // sub-delims
+	',':  true, // sub-delims
+	'-':  true, // unreserved
+	'.':  true, // unreserved
+	':':  true, // IPv6address + Host expression's optional port
+	';':  true, // sub-delims
+	'=':  true, // sub-delims
+	'[':  true,
+	'\'': true, // sub-delims
+	']':  true,
+	'_':  true, // unreserved
+	'~':  true, // unreserved
+}
+
+// ValidHeaderFieldValue reports whether v is a valid "field-value" according to
+// http://www.w3.org/Protocols/rfc2616/rfc2616-sec4.html#sec4.2 :
+//
+//	message-header = field-name ":" [ field-value ]
+//	field-value    = *( field-content | LWS )
+//	field-content  = <the OCTETs making up the field-value
+//	                 and consisting of either *TEXT or combinations
+//	                 of token, separators, and quoted-string>
+//
+// http://www.w3.org/Protocols/rfc2616/rfc2616-sec2.html#sec2.2 :
+//
+//	TEXT           = <any OCTET except CTLs,
+//	                  but including LWS>
+//	LWS            = [CRLF] 1*( SP | HT )
+//	CTL            = <any US-ASCII control character
+//	                 (octets 0 - 31) and DEL (127)>
+//
+// RFC 7230 says:
+//
+//	field-value    = *( field-content / obs-fold )
+//	obj-fold       =  N/A to http2, and deprecated
+//	field-content  = field-vchar [ 1*( SP / HTAB ) field-vchar ]
+//	field-vchar    = VCHAR / obs-text
+//	obs-text       = %x80-FF
+//	VCHAR          = "any visible [USASCII] character"
+//
+// http2 further says: "Similarly, HTTP/2 allows header field values
+// that are not valid. While most of the values that can be encoded
+// will not alter header field parsing, carriage return (CR, ASCII
+// 0xd), line feed (LF, ASCII 0xa), and the zero character (NUL, ASCII
+// 0x0) might be exploited by an attacker if they are translated
+// verbatim. Any request or response that contains a character not
+// permitted in a header field value MUST be treated as malformed
+// (Section 8.1.2.6). Valid characters are defined by the
+// field-content ABNF rule in Section 3.2 of [RFC7230]."
+//
+// This function does not (yet?) properly handle the rejection of
+// strings that begin or end with SP or HTAB.
+func ValidHeaderFieldValue(v string) bool {
+	for i := 0; i < len(v); i++ {
+		b := v[i]
+		if isCTL(b) && !isLWS(b) {
+			return false
+		}
+	}
+	return true
+}
+
+func isASCII(s string) bool {
+	for i := 0; i < len(s); i++ {
+		if s[i] >= utf8.RuneSelf {
+			return false
+		}
+	}
+	return true
+}
+
+// PunycodeHostPort returns the IDNA Punycode version
+// of the provided "host" or "host:port" string.
+func PunycodeHostPort(v string) (string, error) {
+	if isASCII(v) {
+		return v, nil
+	}
+
+	host, port, err := net.SplitHostPort(v)
+	if err != nil {
+		// The input 'v' argument was just a "host" argument,
+		// without a port. This error should not be returned
+		// to the caller.
+		host = v
+		port = ""
+	}
+	host, err = idna.ToASCII(host)
+	if err != nil {
+		// Non-UTF-8? Not representable in Punycode, in any
+		// case.
+		return "", err
+	}
+	if port == "" {
+		return host, nil
+	}
+	return net.JoinHostPort(host, port), nil
+}
diff --git a/contrib/go/_std_1.19/src/vendor/golang.org/x/net/http/httpproxy/proxy.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/http/httpproxy/proxy.go
new file mode 100644
index 0000000000..16994ac134
--- /dev/null
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/http/httpproxy/proxy.go
@@ -0,0 +1,371 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package httpproxy provides support for HTTP proxy determination
+// based on environment variables, as provided by net/http's
+// ProxyFromEnvironment function.
+//
+// The API is not subject to the Go 1 compatibility promise and may change at
+// any time.
+package httpproxy
+
+import (
+	"errors"
+	"fmt"
+	"net"
+	"net/url"
+	"os"
+	"strings"
+	"unicode/utf8"
+
+	"golang.org/x/net/idna"
+)
+
+// Config holds configuration for HTTP proxy settings. See
+// FromEnvironment for details.
+type Config struct {
+	// HTTPProxy represents the value of the HTTP_PROXY or
+	// http_proxy environment variable. It will be used as the proxy
+	// URL for HTTP requests unless overridden by NoProxy.
+	HTTPProxy string
+
+	// HTTPSProxy represents the HTTPS_PROXY or https_proxy
+	// environment variable. It will be used as the proxy URL for
+	// HTTPS requests unless overridden by NoProxy.
+	HTTPSProxy string
+
+	// NoProxy represents the NO_PROXY or no_proxy environment
+	// variable. It specifies a string that contains comma-separated values
+	// specifying hosts that should be excluded from proxying. Each value is
+	// represented by an IP address prefix (1.2.3.4), an IP address prefix in
+	// CIDR notation (1.2.3.4/8), a domain name, or a special DNS label (*).
+	// An IP address prefix and domain name can also include a literal port
+	// number (1.2.3.4:80).
+	// A domain name matches that name and all subdomains. A domain name with
+	// a leading "." matches subdomains only. For example "foo.com" matches
+	// "foo.com" and "bar.foo.com"; ".y.com" matches "x.y.com" but not "y.com".
+	// A single asterisk (*) indicates that no proxying should be done.
+	// A best effort is made to parse the string and errors are
+	// ignored.
+	NoProxy string
+
+	// CGI holds whether the current process is running
+	// as a CGI handler (FromEnvironment infers this from the
+	// presence of a REQUEST_METHOD environment variable).
+	// When this is set, ProxyForURL will return an error
+	// when HTTPProxy applies, because a client could be
+	// setting HTTP_PROXY maliciously. See https://golang.org/s/cgihttpproxy.
+	CGI bool
+}
+
+// config holds the parsed configuration for HTTP proxy settings.
+type config struct {
+	// Config represents the original configuration as defined above.
+	Config
+
+	// httpsProxy is the parsed URL of the HTTPSProxy if defined.
+	httpsProxy *url.URL
+
+	// httpProxy is the parsed URL of the HTTPProxy if defined.
+	httpProxy *url.URL
+
+	// ipMatchers represent all values in the NoProxy that are IP address
+	// prefixes or an IP address in CIDR notation.
+	ipMatchers []matcher
+
+	// domainMatchers represent all values in the NoProxy that are a domain
+	// name or hostname & domain name
+	domainMatchers []matcher
+}
+
+// FromEnvironment returns a Config instance populated from the
+// environment variables HTTP_PROXY, HTTPS_PROXY and NO_PROXY (or the
+// lowercase versions thereof). HTTPS_PROXY takes precedence over
+// HTTP_PROXY for https requests.
+//
+// The environment values may be either a complete URL or a
+// "host[:port]", in which case the "http" scheme is assumed. An error
+// is returned if the value is a different form.
+func FromEnvironment() *Config {
+	return &Config{
+		HTTPProxy:  getEnvAny("HTTP_PROXY", "http_proxy"),
+		HTTPSProxy: getEnvAny("HTTPS_PROXY", "https_proxy"),
+		NoProxy:    getEnvAny("NO_PROXY", "no_proxy"),
+		CGI:        os.Getenv("REQUEST_METHOD") != "",
+	}
+}
+
+func getEnvAny(names ...string) string {
+	for _, n := range names {
+		if val := os.Getenv(n); val != "" {
+			return val
+		}
+	}
+	return ""
+}
+
+// ProxyFunc returns a function that determines the proxy URL to use for
+// a given request URL. Changing the contents of cfg will not affect
+// proxy functions created earlier.
+//
+// A nil URL and nil error are returned if no proxy is defined in the
+// environment, or a proxy should not be used for the given request, as
+// defined by NO_PROXY.
+//
+// As a special case, if req.URL.Host is "localhost" or a loopback address
+// (with or without a port number), then a nil URL and nil error will be returned.
+func (cfg *Config) ProxyFunc() func(reqURL *url.URL) (*url.URL, error) {
+	// Preprocess the Config settings for more efficient evaluation.
+	cfg1 := &config{
+		Config: *cfg,
+	}
+	cfg1.init()
+	return cfg1.proxyForURL
+}
+
+func (cfg *config) proxyForURL(reqURL *url.URL) (*url.URL, error) {
+	var proxy *url.URL
+	if reqURL.Scheme == "https" {
+		proxy = cfg.httpsProxy
+	} else if reqURL.Scheme == "http" {
+		proxy = cfg.httpProxy
+		if proxy != nil && cfg.CGI {
+			return nil, errors.New("refusing to use HTTP_PROXY value in CGI environment; see golang.org/s/cgihttpproxy")
+		}
+	}
+	if proxy == nil {
+		return nil, nil
+	}
+	if !cfg.useProxy(canonicalAddr(reqURL)) {
+		return nil, nil
+	}
+
+	return proxy, nil
+}
+
+func parseProxy(proxy string) (*url.URL, error) {
+	if proxy == "" {
+		return nil, nil
+	}
+
+	proxyURL, err := url.Parse(proxy)
+	if err != nil ||
+		(proxyURL.Scheme != "http" &&
+			proxyURL.Scheme != "https" &&
+			proxyURL.Scheme != "socks5") {
+		// proxy was bogus. Try prepending "http://" to it and
+		// see if that parses correctly. If not, we fall
+		// through and complain about the original one.
+		if proxyURL, err := url.Parse("http://" + proxy); err == nil {
+			return proxyURL, nil
+		}
+	}
+	if err != nil {
+		return nil, fmt.Errorf("invalid proxy address %q: %v", proxy, err)
+	}
+	return proxyURL, nil
+}
+
+// useProxy reports whether requests to addr should use a proxy,
+// according to the NO_PROXY or no_proxy environment variable.
+// addr is always a canonicalAddr with a host and port.
+func (cfg *config) useProxy(addr string) bool {
+	if len(addr) == 0 {
+		return true
+	}
+	host, port, err := net.SplitHostPort(addr)
+	if err != nil {
+		return false
+	}
+	if host == "localhost" {
+		return false
+	}
+	ip := net.ParseIP(host)
+	if ip != nil {
+		if ip.IsLoopback() {
+			return false
+		}
+	}
+
+	addr = strings.ToLower(strings.TrimSpace(host))
+
+	if ip != nil {
+		for _, m := range cfg.ipMatchers {
+			if m.match(addr, port, ip) {
+				return false
+			}
+		}
+	}
+	for _, m := range cfg.domainMatchers {
+		if m.match(addr, port, ip) {
+			return false
+		}
+	}
+	return true
+}
+
+func (c *config) init() {
+	if parsed, err := parseProxy(c.HTTPProxy); err == nil {
+		c.httpProxy = parsed
+	}
+	if parsed, err := parseProxy(c.HTTPSProxy); err == nil {
+		c.httpsProxy = parsed
+	}
+
+	for _, p := range strings.Split(c.NoProxy, ",") {
+		p = strings.ToLower(strings.TrimSpace(p))
+		if len(p) == 0 {
+			continue
+		}
+
+		if p == "*" {
+			c.ipMatchers = []matcher{allMatch{}}
+			c.domainMatchers = []matcher{allMatch{}}
+			return
+		}
+
+		// IPv4/CIDR, IPv6/CIDR
+		if _, pnet, err := net.ParseCIDR(p); err == nil {
+			c.ipMatchers = append(c.ipMatchers, cidrMatch{cidr: pnet})
+			continue
+		}
+
+		// IPv4:port, [IPv6]:port
+		phost, pport, err := net.SplitHostPort(p)
+		if err == nil {
+			if len(phost) == 0 {
+				// There is no host part, likely the entry is malformed; ignore.
+				continue
+			}
+			if phost[0] == '[' && phost[len(phost)-1] == ']' {
+				phost = phost[1 : len(phost)-1]
+			}
+		} else {
+			phost = p
+		}
+		// IPv4, IPv6
+		if pip := net.ParseIP(phost); pip != nil {
+			c.ipMatchers = append(c.ipMatchers, ipMatch{ip: pip, port: pport})
+			continue
+		}
+
+		if len(phost) == 0 {
+			// There is no host part, likely the entry is malformed; ignore.
+			continue
+		}
+
+		// domain.com or domain.com:80
+		// foo.com matches bar.foo.com
+		// .domain.com or .domain.com:port
+		// *.domain.com or *.domain.com:port
+		if strings.HasPrefix(phost, "*.") {
+			phost = phost[1:]
+		}
+		matchHost := false
+		if phost[0] != '.' {
+			matchHost = true
+			phost = "." + phost
+		}
+		if v, err := idnaASCII(phost); err == nil {
+			phost = v
+		}
+		c.domainMatchers = append(c.domainMatchers, domainMatch{host: phost, port: pport, matchHost: matchHost})
+	}
+}
+
+var portMap = map[string]string{
+	"http":   "80",
+	"https":  "443",
+	"socks5": "1080",
+}
+
+// canonicalAddr returns url.Host but always with a ":port" suffix
+func canonicalAddr(url *url.URL) string {
+	addr := url.Hostname()
+	if v, err := idnaASCII(addr); err == nil {
+		addr = v
+	}
+	port := url.Port()
+	if port == "" {
+		port = portMap[url.Scheme]
+	}
+	return net.JoinHostPort(addr, port)
+}
+
+// Given a string of the form "host", "host:port", or "[ipv6::address]:port",
+// return true if the string includes a port.
+func hasPort(s string) bool { return strings.LastIndex(s, ":") > strings.LastIndex(s, "]") }
+
+func idnaASCII(v string) (string, error) {
+	// TODO: Consider removing this check after verifying performance is okay.
+	// Right now punycode verification, length checks, context checks, and the
+	// permissible character tests are all omitted. It also prevents the ToASCII
+	// call from salvaging an invalid IDN, when possible. As a result it may be
+	// possible to have two IDNs that appear identical to the user where the
+	// ASCII-only version causes an error downstream whereas the non-ASCII
+	// version does not.
+	// Note that for correct ASCII IDNs ToASCII will only do considerably more
+	// work, but it will not cause an allocation.
+	if isASCII(v) {
+		return v, nil
+	}
+	return idna.Lookup.ToASCII(v)
+}
+
+func isASCII(s string) bool {
+	for i := 0; i < len(s); i++ {
+		if s[i] >= utf8.RuneSelf {
+			return false
+		}
+	}
+	return true
+}
+
+// matcher represents the matching rule for a given value in the NO_PROXY list
+type matcher interface {
+	// match returns true if the host and optional port or ip and optional port
+	// are allowed
+	match(host, port string, ip net.IP) bool
+}
+
+// allMatch matches on all possible inputs
+type allMatch struct{}
+
+func (a allMatch) match(host, port string, ip net.IP) bool {
+	return true
+}
+
+type cidrMatch struct {
+	cidr *net.IPNet
+}
+
+func (m cidrMatch) match(host, port string, ip net.IP) bool {
+	return m.cidr.Contains(ip)
+}
+
+type ipMatch struct {
+	ip   net.IP
+	port string
+}
+
+func (m ipMatch) match(host, port string, ip net.IP) bool {
+	if m.ip.Equal(ip) {
+		return m.port == "" || m.port == port
+	}
+	return false
+}
+
+type domainMatch struct {
+	host string
+	port string
+
+	matchHost bool
+}
+
+func (m domainMatch) match(host, port string, ip net.IP) bool {
+	if strings.HasSuffix(host, m.host) || (m.matchHost && host == m.host[1:]) {
+		return m.port == "" || m.port == port
+	}
+	return false
+}
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/http2/hpack/encode.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/http2/hpack/encode.go
index 97f17831fc..97f17831fc 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/http2/hpack/encode.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/http2/hpack/encode.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/http2/hpack/hpack.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/http2/hpack/hpack.go
index 85f18a2b0a..85f18a2b0a 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/http2/hpack/hpack.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/http2/hpack/hpack.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/http2/hpack/huffman.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/http2/hpack/huffman.go
index fe0b84ccd4..fe0b84ccd4 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/http2/hpack/huffman.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/http2/hpack/huffman.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/http2/hpack/tables.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/http2/hpack/tables.go
index a66cfbea69..a66cfbea69 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/http2/hpack/tables.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/http2/hpack/tables.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/idna/go118.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/idna/go118.go
index c5c4338dbe..c5c4338dbe 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/idna/go118.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/idna/go118.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/idna/idna10.0.0.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/idna/idna10.0.0.go
index 64ccf85feb..64ccf85feb 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/idna/idna10.0.0.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/idna/idna10.0.0.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/idna/punycode.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/idna/punycode.go
index e8e3ac11a9..e8e3ac11a9 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/idna/punycode.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/idna/punycode.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/idna/tables13.0.0.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/idna/tables13.0.0.go
index 390c5e56d2..390c5e56d2 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/idna/tables13.0.0.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/idna/tables13.0.0.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/idna/trie.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/idna/trie.go
index c4ef847e7a..c4ef847e7a 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/idna/trie.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/idna/trie.go
diff --git a/contrib/go/_std_1.19/src/vendor/golang.org/x/net/idna/trieval.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/idna/trieval.go
new file mode 100644
index 0000000000..9c070a44b3
--- /dev/null
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/idna/trieval.go
@@ -0,0 +1,119 @@
+// Code generated by running "go generate" in golang.org/x/text. DO NOT EDIT.
+
+package idna
+
+// This file contains definitions for interpreting the trie value of the idna
+// trie generated by "go run gen*.go". It is shared by both the generator
+// program and the resultant package. Sharing is achieved by the generator
+// copying gen_trieval.go to trieval.go and changing what's above this comment.
+
+// info holds information from the IDNA mapping table for a single rune. It is
+// the value returned by a trie lookup. In most cases, all information fits in
+// a 16-bit value. For mappings, this value may contain an index into a slice
+// with the mapped string. Such mappings can consist of the actual mapped value
+// or an XOR pattern to be applied to the bytes of the UTF8 encoding of the
+// input rune. This technique is used by the cases packages and reduces the
+// table size significantly.
+//
+// The per-rune values have the following format:
+//
+//	if mapped {
+//	  if inlinedXOR {
+//	    15..13 inline XOR marker
+//	    12..11 unused
+//	    10..3  inline XOR mask
+//	  } else {
+//	    15..3  index into xor or mapping table
+//	  }
+//	} else {
+//	    15..14 unused
+//	    13     mayNeedNorm
+//	    12..11 attributes
+//	    10..8  joining type
+//	     7..3  category type
+//	}
+//	   2  use xor pattern
+//	1..0  mapped category
+//
+// See the definitions below for a more detailed description of the various
+// bits.
+type info uint16
+
+const (
+	catSmallMask = 0x3
+	catBigMask   = 0xF8
+	indexShift   = 3
+	xorBit       = 0x4    // interpret the index as an xor pattern
+	inlineXOR    = 0xE000 // These bits are set if the XOR pattern is inlined.
+
+	joinShift = 8
+	joinMask  = 0x07
+
+	// Attributes
+	attributesMask = 0x1800
+	viramaModifier = 0x1800
+	modifier       = 0x1000
+	rtl            = 0x0800
+
+	mayNeedNorm = 0x2000
+)
+
+// A category corresponds to a category defined in the IDNA mapping table.
+type category uint16
+
+const (
+	unknown              category = 0 // not currently defined in unicode.
+	mapped               category = 1
+	disallowedSTD3Mapped category = 2
+	deviation            category = 3
+)
+
+const (
+	valid               category = 0x08
+	validNV8            category = 0x18
+	validXV8            category = 0x28
+	disallowed          category = 0x40
+	disallowedSTD3Valid category = 0x80
+	ignored             category = 0xC0
+)
+
+// join types and additional rune information
+const (
+	joiningL = (iota + 1)
+	joiningD
+	joiningT
+	joiningR
+
+	//the following types are derived during processing
+	joinZWJ
+	joinZWNJ
+	joinVirama
+	numJoinTypes
+)
+
+func (c info) isMapped() bool {
+	return c&0x3 != 0
+}
+
+func (c info) category() category {
+	small := c & catSmallMask
+	if small != 0 {
+		return category(small)
+	}
+	return category(c & catBigMask)
+}
+
+func (c info) joinType() info {
+	if c.isMapped() {
+		return 0
+	}
+	return (c >> joinShift) & joinMask
+}
+
+func (c info) isModifier() bool {
+	return c&(modifier|catSmallMask) == modifier
+}
+
+func (c info) isViramaModifier() bool {
+	return c&(attributesMask|catSmallMask) == viramaModifier
+}
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/route/address.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/route/address.go
index 1898ed0fad..1898ed0fad 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/route/address.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/route/address.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/route/binary.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/route/binary.go
index a5e28f1e9c..a5e28f1e9c 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/route/binary.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/route/binary.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/route/empty.s b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/route/empty.s
index 90ab4ca3d8..90ab4ca3d8 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/route/empty.s
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/route/empty.s
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/route/interface.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/route/interface.go
index 9e9407830c..9e9407830c 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/route/interface.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/route/interface.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/route/interface_classic.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/route/interface_classic.go
index 85b7e993bb..85b7e993bb 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/route/interface_classic.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/route/interface_classic.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/route/interface_multicast.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/route/interface_multicast.go
index dd0b214baa..dd0b214baa 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/route/interface_multicast.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/route/interface_multicast.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/route/message.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/route/message.go
index 456a8363fe..456a8363fe 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/route/message.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/route/message.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/route/route.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/route/route.go
index fd0019ecc5..fd0019ecc5 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/route/route.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/route/route.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/route/route_classic.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/route/route_classic.go
index d6ee42f1b1..d6ee42f1b1 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/route/route_classic.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/route/route_classic.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/route/sys.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/route/sys.go
index 537484ae5a..537484ae5a 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/route/sys.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/route/sys.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/route/sys_darwin.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/route/sys_darwin.go
index d2daf5c05a..d2daf5c05a 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/route/sys_darwin.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/route/sys_darwin.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/route/syscall.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/route/syscall.go
index 68d37c9621..68d37c9621 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/route/syscall.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/route/syscall.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/route/zsys_darwin.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/route/zsys_darwin.go
index 19e4133f7d..19e4133f7d 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/net/route/zsys_darwin.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/net/route/zsys_darwin.go
diff --git a/contrib/go/_std_1.19/src/vendor/golang.org/x/sys/cpu/byteorder.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/sys/cpu/byteorder.go
new file mode 100644
index 0000000000..271055be0b
--- /dev/null
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/sys/cpu/byteorder.go
@@ -0,0 +1,66 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cpu
+
+import (
+	"runtime"
+)
+
+// byteOrder is a subset of encoding/binary.ByteOrder.
+type byteOrder interface {
+	Uint32([]byte) uint32
+	Uint64([]byte) uint64
+}
+
+type littleEndian struct{}
+type bigEndian struct{}
+
+func (littleEndian) Uint32(b []byte) uint32 {
+	_ = b[3] // bounds check hint to compiler; see golang.org/issue/14808
+	return uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24
+}
+
+func (littleEndian) Uint64(b []byte) uint64 {
+	_ = b[7] // bounds check hint to compiler; see golang.org/issue/14808
+	return uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 |
+		uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56
+}
+
+func (bigEndian) Uint32(b []byte) uint32 {
+	_ = b[3] // bounds check hint to compiler; see golang.org/issue/14808
+	return uint32(b[3]) | uint32(b[2])<<8 | uint32(b[1])<<16 | uint32(b[0])<<24
+}
+
+func (bigEndian) Uint64(b []byte) uint64 {
+	_ = b[7] // bounds check hint to compiler; see golang.org/issue/14808
+	return uint64(b[7]) | uint64(b[6])<<8 | uint64(b[5])<<16 | uint64(b[4])<<24 |
+		uint64(b[3])<<32 | uint64(b[2])<<40 | uint64(b[1])<<48 | uint64(b[0])<<56
+}
+
+// hostByteOrder returns littleEndian on little-endian machines and
+// bigEndian on big-endian machines.
+func hostByteOrder() byteOrder {
+	switch runtime.GOARCH {
+	case "386", "amd64", "amd64p32",
+		"alpha",
+		"arm", "arm64",
+		"loong64",
+		"mipsle", "mips64le", "mips64p32le",
+		"nios2",
+		"ppc64le",
+		"riscv", "riscv64",
+		"sh":
+		return littleEndian{}
+	case "armbe", "arm64be",
+		"m68k",
+		"mips", "mips64", "mips64p32",
+		"ppc", "ppc64",
+		"s390", "s390x",
+		"shbe",
+		"sparc", "sparc64":
+		return bigEndian{}
+	}
+	panic("unknown architecture")
+}
diff --git a/contrib/go/_std_1.19/src/vendor/golang.org/x/sys/cpu/cpu.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/sys/cpu/cpu.go
new file mode 100644
index 0000000000..83f112c4c8
--- /dev/null
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/sys/cpu/cpu.go
@@ -0,0 +1,287 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package cpu implements processor feature detection for
+// various CPU architectures.
+package cpu
+
+import (
+	"os"
+	"strings"
+)
+
+// Initialized reports whether the CPU features were initialized.
+//
+// For some GOOS/GOARCH combinations initialization of the CPU features depends
+// on reading an operating specific file, e.g. /proc/self/auxv on linux/arm
+// Initialized will report false if reading the file fails.
+var Initialized bool
+
+// CacheLinePad is used to pad structs to avoid false sharing.
+type CacheLinePad struct{ _ [cacheLineSize]byte }
+
+// X86 contains the supported CPU features of the
+// current X86/AMD64 platform. If the current platform
+// is not X86/AMD64 then all feature flags are false.
+//
+// X86 is padded to avoid false sharing. Further the HasAVX
+// and HasAVX2 are only set if the OS supports XMM and YMM
+// registers in addition to the CPUID feature bit being set.
+var X86 struct {
+	_                   CacheLinePad
+	HasAES              bool // AES hardware implementation (AES NI)
+	HasADX              bool // Multi-precision add-carry instruction extensions
+	HasAVX              bool // Advanced vector extension
+	HasAVX2             bool // Advanced vector extension 2
+	HasAVX512           bool // Advanced vector extension 512
+	HasAVX512F          bool // Advanced vector extension 512 Foundation Instructions
+	HasAVX512CD         bool // Advanced vector extension 512 Conflict Detection Instructions
+	HasAVX512ER         bool // Advanced vector extension 512 Exponential and Reciprocal Instructions
+	HasAVX512PF         bool // Advanced vector extension 512 Prefetch Instructions Instructions
+	HasAVX512VL         bool // Advanced vector extension 512 Vector Length Extensions
+	HasAVX512BW         bool // Advanced vector extension 512 Byte and Word Instructions
+	HasAVX512DQ         bool // Advanced vector extension 512 Doubleword and Quadword Instructions
+	HasAVX512IFMA       bool // Advanced vector extension 512 Integer Fused Multiply Add
+	HasAVX512VBMI       bool // Advanced vector extension 512 Vector Byte Manipulation Instructions
+	HasAVX5124VNNIW     bool // Advanced vector extension 512 Vector Neural Network Instructions Word variable precision
+	HasAVX5124FMAPS     bool // Advanced vector extension 512 Fused Multiply Accumulation Packed Single precision
+	HasAVX512VPOPCNTDQ  bool // Advanced vector extension 512 Double and quad word population count instructions
+	HasAVX512VPCLMULQDQ bool // Advanced vector extension 512 Vector carry-less multiply operations
+	HasAVX512VNNI       bool // Advanced vector extension 512 Vector Neural Network Instructions
+	HasAVX512GFNI       bool // Advanced vector extension 512 Galois field New Instructions
+	HasAVX512VAES       bool // Advanced vector extension 512 Vector AES instructions
+	HasAVX512VBMI2      bool // Advanced vector extension 512 Vector Byte Manipulation Instructions 2
+	HasAVX512BITALG     bool // Advanced vector extension 512 Bit Algorithms
+	HasAVX512BF16       bool // Advanced vector extension 512 BFloat16 Instructions
+	HasBMI1             bool // Bit manipulation instruction set 1
+	HasBMI2             bool // Bit manipulation instruction set 2
+	HasCX16             bool // Compare and exchange 16 Bytes
+	HasERMS             bool // Enhanced REP for MOVSB and STOSB
+	HasFMA              bool // Fused-multiply-add instructions
+	HasOSXSAVE          bool // OS supports XSAVE/XRESTOR for saving/restoring XMM registers.
+	HasPCLMULQDQ        bool // PCLMULQDQ instruction - most often used for AES-GCM
+	HasPOPCNT           bool // Hamming weight instruction POPCNT.
+	HasRDRAND           bool // RDRAND instruction (on-chip random number generator)
+	HasRDSEED           bool // RDSEED instruction (on-chip random number generator)
+	HasSSE2             bool // Streaming SIMD extension 2 (always available on amd64)
+	HasSSE3             bool // Streaming SIMD extension 3
+	HasSSSE3            bool // Supplemental streaming SIMD extension 3
+	HasSSE41            bool // Streaming SIMD extension 4 and 4.1
+	HasSSE42            bool // Streaming SIMD extension 4 and 4.2
+	_                   CacheLinePad
+}
+
+// ARM64 contains the supported CPU features of the
+// current ARMv8(aarch64) platform. If the current platform
+// is not arm64 then all feature flags are false.
+var ARM64 struct {
+	_           CacheLinePad
+	HasFP       bool // Floating-point instruction set (always available)
+	HasASIMD    bool // Advanced SIMD (always available)
+	HasEVTSTRM  bool // Event stream support
+	HasAES      bool // AES hardware implementation
+	HasPMULL    bool // Polynomial multiplication instruction set
+	HasSHA1     bool // SHA1 hardware implementation
+	HasSHA2     bool // SHA2 hardware implementation
+	HasCRC32    bool // CRC32 hardware implementation
+	HasATOMICS  bool // Atomic memory operation instruction set
+	HasFPHP     bool // Half precision floating-point instruction set
+	HasASIMDHP  bool // Advanced SIMD half precision instruction set
+	HasCPUID    bool // CPUID identification scheme registers
+	HasASIMDRDM bool // Rounding double multiply add/subtract instruction set
+	HasJSCVT    bool // Javascript conversion from floating-point to integer
+	HasFCMA     bool // Floating-point multiplication and addition of complex numbers
+	HasLRCPC    bool // Release Consistent processor consistent support
+	HasDCPOP    bool // Persistent memory support
+	HasSHA3     bool // SHA3 hardware implementation
+	HasSM3      bool // SM3 hardware implementation
+	HasSM4      bool // SM4 hardware implementation
+	HasASIMDDP  bool // Advanced SIMD double precision instruction set
+	HasSHA512   bool // SHA512 hardware implementation
+	HasSVE      bool // Scalable Vector Extensions
+	HasASIMDFHM bool // Advanced SIMD multiplication FP16 to FP32
+	_           CacheLinePad
+}
+
+// ARM contains the supported CPU features of the current ARM (32-bit) platform.
+// All feature flags are false if:
+//  1. the current platform is not arm, or
+//  2. the current operating system is not Linux.
+var ARM struct {
+	_           CacheLinePad
+	HasSWP      bool // SWP instruction support
+	HasHALF     bool // Half-word load and store support
+	HasTHUMB    bool // ARM Thumb instruction set
+	Has26BIT    bool // Address space limited to 26-bits
+	HasFASTMUL  bool // 32-bit operand, 64-bit result multiplication support
+	HasFPA      bool // Floating point arithmetic support
+	HasVFP      bool // Vector floating point support
+	HasEDSP     bool // DSP Extensions support
+	HasJAVA     bool // Java instruction set
+	HasIWMMXT   bool // Intel Wireless MMX technology support
+	HasCRUNCH   bool // MaverickCrunch context switching and handling
+	HasTHUMBEE  bool // Thumb EE instruction set
+	HasNEON     bool // NEON instruction set
+	HasVFPv3    bool // Vector floating point version 3 support
+	HasVFPv3D16 bool // Vector floating point version 3 D8-D15
+	HasTLS      bool // Thread local storage support
+	HasVFPv4    bool // Vector floating point version 4 support
+	HasIDIVA    bool // Integer divide instruction support in ARM mode
+	HasIDIVT    bool // Integer divide instruction support in Thumb mode
+	HasVFPD32   bool // Vector floating point version 3 D15-D31
+	HasLPAE     bool // Large Physical Address Extensions
+	HasEVTSTRM  bool // Event stream support
+	HasAES      bool // AES hardware implementation
+	HasPMULL    bool // Polynomial multiplication instruction set
+	HasSHA1     bool // SHA1 hardware implementation
+	HasSHA2     bool // SHA2 hardware implementation
+	HasCRC32    bool // CRC32 hardware implementation
+	_           CacheLinePad
+}
+
+// MIPS64X contains the supported CPU features of the current mips64/mips64le
+// platforms. If the current platform is not mips64/mips64le or the current
+// operating system is not Linux then all feature flags are false.
+var MIPS64X struct {
+	_      CacheLinePad
+	HasMSA bool // MIPS SIMD architecture
+	_      CacheLinePad
+}
+
+// PPC64 contains the supported CPU features of the current ppc64/ppc64le platforms.
+// If the current platform is not ppc64/ppc64le then all feature flags are false.
+//
+// For ppc64/ppc64le, it is safe to check only for ISA level starting on ISA v3.00,
+// since there are no optional categories. There are some exceptions that also
+// require kernel support to work (DARN, SCV), so there are feature bits for
+// those as well. The struct is padded to avoid false sharing.
+var PPC64 struct {
+	_        CacheLinePad
+	HasDARN  bool // Hardware random number generator (requires kernel enablement)
+	HasSCV   bool // Syscall vectored (requires kernel enablement)
+	IsPOWER8 bool // ISA v2.07 (POWER8)
+	IsPOWER9 bool // ISA v3.00 (POWER9), implies IsPOWER8
+	_        CacheLinePad
+}
+
+// S390X contains the supported CPU features of the current IBM Z
+// (s390x) platform. If the current platform is not IBM Z then all
+// feature flags are false.
+//
+// S390X is padded to avoid false sharing. Further HasVX is only set
+// if the OS supports vector registers in addition to the STFLE
+// feature bit being set.
+var S390X struct {
+	_         CacheLinePad
+	HasZARCH  bool // z/Architecture mode is active [mandatory]
+	HasSTFLE  bool // store facility list extended
+	HasLDISP  bool // long (20-bit) displacements
+	HasEIMM   bool // 32-bit immediates
+	HasDFP    bool // decimal floating point
+	HasETF3EH bool // ETF-3 enhanced
+	HasMSA    bool // message security assist (CPACF)
+	HasAES    bool // KM-AES{128,192,256} functions
+	HasAESCBC bool // KMC-AES{128,192,256} functions
+	HasAESCTR bool // KMCTR-AES{128,192,256} functions
+	HasAESGCM bool // KMA-GCM-AES{128,192,256} functions
+	HasGHASH  bool // KIMD-GHASH function
+	HasSHA1   bool // K{I,L}MD-SHA-1 functions
+	HasSHA256 bool // K{I,L}MD-SHA-256 functions
+	HasSHA512 bool // K{I,L}MD-SHA-512 functions
+	HasSHA3   bool // K{I,L}MD-SHA3-{224,256,384,512} and K{I,L}MD-SHAKE-{128,256} functions
+	HasVX     bool // vector facility
+	HasVXE    bool // vector-enhancements facility 1
+	_         CacheLinePad
+}
+
+func init() {
+	archInit()
+	initOptions()
+	processOptions()
+}
+
+// options contains the cpu debug options that can be used in GODEBUG.
+// Options are arch dependent and are added by the arch specific initOptions functions.
+// Features that are mandatory for the specific GOARCH should have the Required field set
+// (e.g. SSE2 on amd64).
+var options []option
+
+// Option names should be lower case. e.g. avx instead of AVX.
+type option struct {
+	Name      string
+	Feature   *bool
+	Specified bool // whether feature value was specified in GODEBUG
+	Enable    bool // whether feature should be enabled
+	Required  bool // whether feature is mandatory and can not be disabled
+}
+
+func processOptions() {
+	env := os.Getenv("GODEBUG")
+field:
+	for env != "" {
+		field := ""
+		i := strings.IndexByte(env, ',')
+		if i < 0 {
+			field, env = env, ""
+		} else {
+			field, env = env[:i], env[i+1:]
+		}
+		if len(field) < 4 || field[:4] != "cpu." {
+			continue
+		}
+		i = strings.IndexByte(field, '=')
+		if i < 0 {
+			print("GODEBUG sys/cpu: no value specified for \"", field, "\"\n")
+			continue
+		}
+		key, value := field[4:i], field[i+1:] // e.g. "SSE2", "on"
+
+		var enable bool
+		switch value {
+		case "on":
+			enable = true
+		case "off":
+			enable = false
+		default:
+			print("GODEBUG sys/cpu: value \"", value, "\" not supported for cpu option \"", key, "\"\n")
+			continue field
+		}
+
+		if key == "all" {
+			for i := range options {
+				options[i].Specified = true
+				options[i].Enable = enable || options[i].Required
+			}
+			continue field
+		}
+
+		for i := range options {
+			if options[i].Name == key {
+				options[i].Specified = true
+				options[i].Enable = enable
+				continue field
+			}
+		}
+
+		print("GODEBUG sys/cpu: unknown cpu feature \"", key, "\"\n")
+	}
+
+	for _, o := range options {
+		if !o.Specified {
+			continue
+		}
+
+		if o.Enable && !*o.Feature {
+			print("GODEBUG sys/cpu: can not enable \"", o.Name, "\", missing CPU support\n")
+			continue
+		}
+
+		if !o.Enable && o.Required {
+			print("GODEBUG sys/cpu: can not disable \"", o.Name, "\", required CPU feature\n")
+			continue
+		}
+
+		*o.Feature = o.Enable
+	}
+}
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/sys/cpu/cpu_gc_x86.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/sys/cpu/cpu_gc_x86.go
index fa7cdb9bcd..fa7cdb9bcd 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/sys/cpu/cpu_gc_x86.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/sys/cpu/cpu_gc_x86.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/sys/cpu/cpu_linux_noinit.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/sys/cpu/cpu_linux_noinit.go
index f4992b1a59..f4992b1a59 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/sys/cpu/cpu_linux_noinit.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/sys/cpu/cpu_linux_noinit.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/sys/cpu/cpu_x86.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/sys/cpu/cpu_x86.go
index f5aacfc825..f5aacfc825 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/sys/cpu/cpu_x86.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/sys/cpu/cpu_x86.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/sys/cpu/cpu_x86.s b/contrib/go/_std_1.19/src/vendor/golang.org/x/sys/cpu/cpu_x86.s
index 39acab2ff5..39acab2ff5 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/sys/cpu/cpu_x86.s
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/sys/cpu/cpu_x86.s
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/sys/cpu/hwcap_linux.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/sys/cpu/hwcap_linux.go
index f3baa37932..f3baa37932 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/sys/cpu/hwcap_linux.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/sys/cpu/hwcap_linux.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/secure/bidirule/bidirule.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/secure/bidirule/bidirule.go
index e2b70f76c2..e2b70f76c2 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/secure/bidirule/bidirule.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/secure/bidirule/bidirule.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/secure/bidirule/bidirule10.0.0.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/secure/bidirule/bidirule10.0.0.go
index 8a7392c4a1..8a7392c4a1 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/secure/bidirule/bidirule10.0.0.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/secure/bidirule/bidirule10.0.0.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/transform/transform.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/transform/transform.go
index 48ec64b40c..48ec64b40c 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/transform/transform.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/transform/transform.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/bidi/bidi.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/bidi/bidi.go
index fd057601bd..fd057601bd 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/bidi/bidi.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/bidi/bidi.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/bidi/bracket.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/bidi/bracket.go
index 1853939791..1853939791 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/bidi/bracket.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/bidi/bracket.go
diff --git a/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/bidi/core.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/bidi/core.go
new file mode 100644
index 0000000000..9d2ae547b5
--- /dev/null
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/bidi/core.go
@@ -0,0 +1,1071 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bidi
+
+import (
+	"fmt"
+	"log"
+)
+
+// This implementation is a port based on the reference implementation found at:
+// https://www.unicode.org/Public/PROGRAMS/BidiReferenceJava/
+//
+// described in Unicode Bidirectional Algorithm (UAX #9).
+//
+// Input:
+// There are two levels of input to the algorithm, since clients may prefer to
+// supply some information from out-of-band sources rather than relying on the
+// default behavior.
+//
+// - Bidi class array
+// - Bidi class array, with externally supplied base line direction
+//
+// Output:
+// Output is separated into several stages:
+//
+//  - levels array over entire paragraph
+//  - reordering array over entire paragraph
+//  - levels array over line
+//  - reordering array over line
+//
+// Note that for conformance to the Unicode Bidirectional Algorithm,
+// implementations are only required to generate correct reordering and
+// character directionality (odd or even levels) over a line. Generating
+// identical level arrays over a line is not required. Bidi explicit format
+// codes (LRE, RLE, LRO, RLO, PDF) and BN can be assigned arbitrary levels and
+// positions as long as the rest of the input is properly reordered.
+//
+// As the algorithm is defined to operate on a single paragraph at a time, this
+// implementation is written to handle single paragraphs. Thus rule P1 is
+// presumed by this implementation-- the data provided to the implementation is
+// assumed to be a single paragraph, and either contains no 'B' codes, or a
+// single 'B' code at the end of the input. 'B' is allowed as input to
+// illustrate how the algorithm assigns it a level.
+//
+// Also note that rules L3 and L4 depend on the rendering engine that uses the
+// result of the bidi algorithm. This implementation assumes that the rendering
+// engine expects combining marks in visual order (e.g. to the left of their
+// base character in RTL runs) and that it adjusts the glyphs used to render
+// mirrored characters that are in RTL runs so that they render appropriately.
+
+// level is the embedding level of a character. Even embedding levels indicate
+// left-to-right order and odd levels indicate right-to-left order. The special
+// level of -1 is reserved for undefined order.
+type level int8
+
+const implicitLevel level = -1
+
+// in returns if x is equal to any of the values in set.
+func (c Class) in(set ...Class) bool {
+	for _, s := range set {
+		if c == s {
+			return true
+		}
+	}
+	return false
+}
+
+// A paragraph contains the state of a paragraph.
+type paragraph struct {
+	initialTypes []Class
+
+	// Arrays of properties needed for paired bracket evaluation in N0
+	pairTypes  []bracketType // paired Bracket types for paragraph
+	pairValues []rune        // rune for opening bracket or pbOpen and pbClose; 0 for pbNone
+
+	embeddingLevel level // default: = implicitLevel;
+
+	// at the paragraph levels
+	resultTypes  []Class
+	resultLevels []level
+
+	// Index of matching PDI for isolate initiator characters. For other
+	// characters, the value of matchingPDI will be set to -1. For isolate
+	// initiators with no matching PDI, matchingPDI will be set to the length of
+	// the input string.
+	matchingPDI []int
+
+	// Index of matching isolate initiator for PDI characters. For other
+	// characters, and for PDIs with no matching isolate initiator, the value of
+	// matchingIsolateInitiator will be set to -1.
+	matchingIsolateInitiator []int
+}
+
+// newParagraph initializes a paragraph. The user needs to supply a few arrays
+// corresponding to the preprocessed text input. The types correspond to the
+// Unicode BiDi classes for each rune. pairTypes indicates the bracket type for
+// each rune. pairValues provides a unique bracket class identifier for each
+// rune (suggested is the rune of the open bracket for opening and matching
+// close brackets, after normalization). The embedding levels are optional, but
+// may be supplied to encode embedding levels of styled text.
+func newParagraph(types []Class, pairTypes []bracketType, pairValues []rune, levels level) (*paragraph, error) {
+	var err error
+	if err = validateTypes(types); err != nil {
+		return nil, err
+	}
+	if err = validatePbTypes(pairTypes); err != nil {
+		return nil, err
+	}
+	if err = validatePbValues(pairValues, pairTypes); err != nil {
+		return nil, err
+	}
+	if err = validateParagraphEmbeddingLevel(levels); err != nil {
+		return nil, err
+	}
+
+	p := &paragraph{
+		initialTypes:   append([]Class(nil), types...),
+		embeddingLevel: levels,
+
+		pairTypes:  pairTypes,
+		pairValues: pairValues,
+
+		resultTypes: append([]Class(nil), types...),
+	}
+	p.run()
+	return p, nil
+}
+
+func (p *paragraph) Len() int { return len(p.initialTypes) }
+
+// The algorithm. Does not include line-based processing (Rules L1, L2).
+// These are applied later in the line-based phase of the algorithm.
+func (p *paragraph) run() {
+	p.determineMatchingIsolates()
+
+	// 1) determining the paragraph level
+	// Rule P1 is the requirement for entering this algorithm.
+	// Rules P2, P3.
+	// If no externally supplied paragraph embedding level, use default.
+	if p.embeddingLevel == implicitLevel {
+		p.embeddingLevel = p.determineParagraphEmbeddingLevel(0, p.Len())
+	}
+
+	// Initialize result levels to paragraph embedding level.
+	p.resultLevels = make([]level, p.Len())
+	setLevels(p.resultLevels, p.embeddingLevel)
+
+	// 2) Explicit levels and directions
+	// Rules X1-X8.
+	p.determineExplicitEmbeddingLevels()
+
+	// Rule X9.
+	// We do not remove the embeddings, the overrides, the PDFs, and the BNs
+	// from the string explicitly. But they are not copied into isolating run
+	// sequences when they are created, so they are removed for all
+	// practical purposes.
+
+	// Rule X10.
+	// Run remainder of algorithm one isolating run sequence at a time
+	for _, seq := range p.determineIsolatingRunSequences() {
+		// 3) resolving weak types
+		// Rules W1-W7.
+		seq.resolveWeakTypes()
+
+		// 4a) resolving paired brackets
+		// Rule N0
+		resolvePairedBrackets(seq)
+
+		// 4b) resolving neutral types
+		// Rules N1-N3.
+		seq.resolveNeutralTypes()
+
+		// 5) resolving implicit embedding levels
+		// Rules I1, I2.
+		seq.resolveImplicitLevels()
+
+		// Apply the computed levels and types
+		seq.applyLevelsAndTypes()
+	}
+
+	// Assign appropriate levels to 'hide' LREs, RLEs, LROs, RLOs, PDFs, and
+	// BNs. This is for convenience, so the resulting level array will have
+	// a value for every character.
+	p.assignLevelsToCharactersRemovedByX9()
+}
+
+// determineMatchingIsolates determines the matching PDI for each isolate
+// initiator and vice versa.
+//
+// Definition BD9.
+//
+// At the end of this function:
+//
+//   - The member variable matchingPDI is set to point to the index of the
+//     matching PDI character for each isolate initiator character. If there is
+//     no matching PDI, it is set to the length of the input text. For other
+//     characters, it is set to -1.
+//   - The member variable matchingIsolateInitiator is set to point to the
+//     index of the matching isolate initiator character for each PDI character.
+//     If there is no matching isolate initiator, or the character is not a PDI,
+//     it is set to -1.
+func (p *paragraph) determineMatchingIsolates() {
+	p.matchingPDI = make([]int, p.Len())
+	p.matchingIsolateInitiator = make([]int, p.Len())
+
+	for i := range p.matchingIsolateInitiator {
+		p.matchingIsolateInitiator[i] = -1
+	}
+
+	for i := range p.matchingPDI {
+		p.matchingPDI[i] = -1
+
+		if t := p.resultTypes[i]; t.in(LRI, RLI, FSI) {
+			depthCounter := 1
+			for j := i + 1; j < p.Len(); j++ {
+				if u := p.resultTypes[j]; u.in(LRI, RLI, FSI) {
+					depthCounter++
+				} else if u == PDI {
+					if depthCounter--; depthCounter == 0 {
+						p.matchingPDI[i] = j
+						p.matchingIsolateInitiator[j] = i
+						break
+					}
+				}
+			}
+			if p.matchingPDI[i] == -1 {
+				p.matchingPDI[i] = p.Len()
+			}
+		}
+	}
+}
+
+// determineParagraphEmbeddingLevel reports the resolved paragraph direction of
+// the substring limited by the given range [start, end).
+//
+// Determines the paragraph level based on rules P2, P3. This is also used
+// in rule X5c to find if an FSI should resolve to LRI or RLI.
+func (p *paragraph) determineParagraphEmbeddingLevel(start, end int) level {
+	var strongType Class = unknownClass
+
+	// Rule P2.
+	for i := start; i < end; i++ {
+		if t := p.resultTypes[i]; t.in(L, AL, R) {
+			strongType = t
+			break
+		} else if t.in(FSI, LRI, RLI) {
+			i = p.matchingPDI[i] // skip over to the matching PDI
+			if i > end {
+				log.Panic("assert (i <= end)")
+			}
+		}
+	}
+	// Rule P3.
+	switch strongType {
+	case unknownClass: // none found
+		// default embedding level when no strong types found is 0.
+		return 0
+	case L:
+		return 0
+	default: // AL, R
+		return 1
+	}
+}
+
+const maxDepth = 125
+
+// This stack will store the embedding levels and override and isolated
+// statuses
+type directionalStatusStack struct {
+	stackCounter        int
+	embeddingLevelStack [maxDepth + 1]level
+	overrideStatusStack [maxDepth + 1]Class
+	isolateStatusStack  [maxDepth + 1]bool
+}
+
+func (s *directionalStatusStack) empty()     { s.stackCounter = 0 }
+func (s *directionalStatusStack) pop()       { s.stackCounter-- }
+func (s *directionalStatusStack) depth() int { return s.stackCounter }
+
+func (s *directionalStatusStack) push(level level, overrideStatus Class, isolateStatus bool) {
+	s.embeddingLevelStack[s.stackCounter] = level
+	s.overrideStatusStack[s.stackCounter] = overrideStatus
+	s.isolateStatusStack[s.stackCounter] = isolateStatus
+	s.stackCounter++
+}
+
+func (s *directionalStatusStack) lastEmbeddingLevel() level {
+	return s.embeddingLevelStack[s.stackCounter-1]
+}
+
+func (s *directionalStatusStack) lastDirectionalOverrideStatus() Class {
+	return s.overrideStatusStack[s.stackCounter-1]
+}
+
+func (s *directionalStatusStack) lastDirectionalIsolateStatus() bool {
+	return s.isolateStatusStack[s.stackCounter-1]
+}
+
+// Determine explicit levels using rules X1 - X8
+func (p *paragraph) determineExplicitEmbeddingLevels() {
+	var stack directionalStatusStack
+	var overflowIsolateCount, overflowEmbeddingCount, validIsolateCount int
+
+	// Rule X1.
+	stack.push(p.embeddingLevel, ON, false)
+
+	for i, t := range p.resultTypes {
+		// Rules X2, X3, X4, X5, X5a, X5b, X5c
+		switch t {
+		case RLE, LRE, RLO, LRO, RLI, LRI, FSI:
+			isIsolate := t.in(RLI, LRI, FSI)
+			isRTL := t.in(RLE, RLO, RLI)
+
+			// override if this is an FSI that resolves to RLI
+			if t == FSI {
+				isRTL = (p.determineParagraphEmbeddingLevel(i+1, p.matchingPDI[i]) == 1)
+			}
+			if isIsolate {
+				p.resultLevels[i] = stack.lastEmbeddingLevel()
+				if stack.lastDirectionalOverrideStatus() != ON {
+					p.resultTypes[i] = stack.lastDirectionalOverrideStatus()
+				}
+			}
+
+			var newLevel level
+			if isRTL {
+				// least greater odd
+				newLevel = (stack.lastEmbeddingLevel() + 1) | 1
+			} else {
+				// least greater even
+				newLevel = (stack.lastEmbeddingLevel() + 2) &^ 1
+			}
+
+			if newLevel <= maxDepth && overflowIsolateCount == 0 && overflowEmbeddingCount == 0 {
+				if isIsolate {
+					validIsolateCount++
+				}
+				// Push new embedding level, override status, and isolated
+				// status.
+				// No check for valid stack counter, since the level check
+				// suffices.
+				switch t {
+				case LRO:
+					stack.push(newLevel, L, isIsolate)
+				case RLO:
+					stack.push(newLevel, R, isIsolate)
+				default:
+					stack.push(newLevel, ON, isIsolate)
+				}
+				// Not really part of the spec
+				if !isIsolate {
+					p.resultLevels[i] = newLevel
+				}
+			} else {
+				// This is an invalid explicit formatting character,
+				// so apply the "Otherwise" part of rules X2-X5b.
+				if isIsolate {
+					overflowIsolateCount++
+				} else { // !isIsolate
+					if overflowIsolateCount == 0 {
+						overflowEmbeddingCount++
+					}
+				}
+			}
+
+		// Rule X6a
+		case PDI:
+			if overflowIsolateCount > 0 {
+				overflowIsolateCount--
+			} else if validIsolateCount == 0 {
+				// do nothing
+			} else {
+				overflowEmbeddingCount = 0
+				for !stack.lastDirectionalIsolateStatus() {
+					stack.pop()
+				}
+				stack.pop()
+				validIsolateCount--
+			}
+			p.resultLevels[i] = stack.lastEmbeddingLevel()
+
+		// Rule X7
+		case PDF:
+			// Not really part of the spec
+			p.resultLevels[i] = stack.lastEmbeddingLevel()
+
+			if overflowIsolateCount > 0 {
+				// do nothing
+			} else if overflowEmbeddingCount > 0 {
+				overflowEmbeddingCount--
+			} else if !stack.lastDirectionalIsolateStatus() && stack.depth() >= 2 {
+				stack.pop()
+			}
+
+		case B: // paragraph separator.
+			// Rule X8.
+
+			// These values are reset for clarity, in this implementation B
+			// can only occur as the last code in the array.
+			stack.empty()
+			overflowIsolateCount = 0
+			overflowEmbeddingCount = 0
+			validIsolateCount = 0
+			p.resultLevels[i] = p.embeddingLevel
+
+		default:
+			p.resultLevels[i] = stack.lastEmbeddingLevel()
+			if stack.lastDirectionalOverrideStatus() != ON {
+				p.resultTypes[i] = stack.lastDirectionalOverrideStatus()
+			}
+		}
+	}
+}
+
+type isolatingRunSequence struct {
+	p *paragraph
+
+	indexes []int // indexes to the original string
+
+	types          []Class // type of each character using the index
+	resolvedLevels []level // resolved levels after application of rules
+	level          level
+	sos, eos       Class
+}
+
+func (i *isolatingRunSequence) Len() int { return len(i.indexes) }
+
+func maxLevel(a, b level) level {
+	if a > b {
+		return a
+	}
+	return b
+}
+
+// Rule X10, second bullet: Determine the start-of-sequence (sos) and end-of-sequence (eos) types,
+// either L or R, for each isolating run sequence.
+func (p *paragraph) isolatingRunSequence(indexes []int) *isolatingRunSequence {
+	length := len(indexes)
+	types := make([]Class, length)
+	for i, x := range indexes {
+		types[i] = p.resultTypes[x]
+	}
+
+	// assign level, sos and eos
+	prevChar := indexes[0] - 1
+	for prevChar >= 0 && isRemovedByX9(p.initialTypes[prevChar]) {
+		prevChar--
+	}
+	prevLevel := p.embeddingLevel
+	if prevChar >= 0 {
+		prevLevel = p.resultLevels[prevChar]
+	}
+
+	var succLevel level
+	lastType := types[length-1]
+	if lastType.in(LRI, RLI, FSI) {
+		succLevel = p.embeddingLevel
+	} else {
+		// the first character after the end of run sequence
+		limit := indexes[length-1] + 1
+		for ; limit < p.Len() && isRemovedByX9(p.initialTypes[limit]); limit++ {
+
+		}
+		succLevel = p.embeddingLevel
+		if limit < p.Len() {
+			succLevel = p.resultLevels[limit]
+		}
+	}
+	level := p.resultLevels[indexes[0]]
+	return &isolatingRunSequence{
+		p:       p,
+		indexes: indexes,
+		types:   types,
+		level:   level,
+		sos:     typeForLevel(maxLevel(prevLevel, level)),
+		eos:     typeForLevel(maxLevel(succLevel, level)),
+	}
+}
+
+// Resolving weak types Rules W1-W7.
+//
+// Note that some weak types (EN, AN) remain after this processing is
+// complete.
+func (s *isolatingRunSequence) resolveWeakTypes() {
+
+	// on entry, only these types remain
+	s.assertOnly(L, R, AL, EN, ES, ET, AN, CS, B, S, WS, ON, NSM, LRI, RLI, FSI, PDI)
+
+	// Rule W1.
+	// Changes all NSMs.
+	precedingCharacterType := s.sos
+	for i, t := range s.types {
+		if t == NSM {
+			s.types[i] = precedingCharacterType
+		} else {
+			// if t.in(LRI, RLI, FSI, PDI) {
+			// 	precedingCharacterType = ON
+			// }
+			precedingCharacterType = t
+		}
+	}
+
+	// Rule W2.
+	// EN does not change at the start of the run, because sos != AL.
+	for i, t := range s.types {
+		if t == EN {
+			for j := i - 1; j >= 0; j-- {
+				if t := s.types[j]; t.in(L, R, AL) {
+					if t == AL {
+						s.types[i] = AN
+					}
+					break
+				}
+			}
+		}
+	}
+
+	// Rule W3.
+	for i, t := range s.types {
+		if t == AL {
+			s.types[i] = R
+		}
+	}
+
+	// Rule W4.
+	// Since there must be values on both sides for this rule to have an
+	// effect, the scan skips the first and last value.
+	//
+	// Although the scan proceeds left to right, and changes the type
+	// values in a way that would appear to affect the computations
+	// later in the scan, there is actually no problem. A change in the
+	// current value can only affect the value to its immediate right,
+	// and only affect it if it is ES or CS. But the current value can
+	// only change if the value to its right is not ES or CS. Thus
+	// either the current value will not change, or its change will have
+	// no effect on the remainder of the analysis.
+
+	for i := 1; i < s.Len()-1; i++ {
+		t := s.types[i]
+		if t == ES || t == CS {
+			prevSepType := s.types[i-1]
+			succSepType := s.types[i+1]
+			if prevSepType == EN && succSepType == EN {
+				s.types[i] = EN
+			} else if s.types[i] == CS && prevSepType == AN && succSepType == AN {
+				s.types[i] = AN
+			}
+		}
+	}
+
+	// Rule W5.
+	for i, t := range s.types {
+		if t == ET {
+			// locate end of sequence
+			runStart := i
+			runEnd := s.findRunLimit(runStart, ET)
+
+			// check values at ends of sequence
+			t := s.sos
+			if runStart > 0 {
+				t = s.types[runStart-1]
+			}
+			if t != EN {
+				t = s.eos
+				if runEnd < len(s.types) {
+					t = s.types[runEnd]
+				}
+			}
+			if t == EN {
+				setTypes(s.types[runStart:runEnd], EN)
+			}
+			// continue at end of sequence
+			i = runEnd
+		}
+	}
+
+	// Rule W6.
+	for i, t := range s.types {
+		if t.in(ES, ET, CS) {
+			s.types[i] = ON
+		}
+	}
+
+	// Rule W7.
+	for i, t := range s.types {
+		if t == EN {
+			// set default if we reach start of run
+			prevStrongType := s.sos
+			for j := i - 1; j >= 0; j-- {
+				t = s.types[j]
+				if t == L || t == R { // AL's have been changed to R
+					prevStrongType = t
+					break
+				}
+			}
+			if prevStrongType == L {
+				s.types[i] = L
+			}
+		}
+	}
+}
+
+// 6) resolving neutral types Rules N1-N2.
+func (s *isolatingRunSequence) resolveNeutralTypes() {
+
+	// on entry, only these types can be in resultTypes
+	s.assertOnly(L, R, EN, AN, B, S, WS, ON, RLI, LRI, FSI, PDI)
+
+	for i, t := range s.types {
+		switch t {
+		case WS, ON, B, S, RLI, LRI, FSI, PDI:
+			// find bounds of run of neutrals
+			runStart := i
+			runEnd := s.findRunLimit(runStart, B, S, WS, ON, RLI, LRI, FSI, PDI)
+
+			// determine effective types at ends of run
+			var leadType, trailType Class
+
+			// Note that the character found can only be L, R, AN, or
+			// EN.
+			if runStart == 0 {
+				leadType = s.sos
+			} else {
+				leadType = s.types[runStart-1]
+				if leadType.in(AN, EN) {
+					leadType = R
+				}
+			}
+			if runEnd == len(s.types) {
+				trailType = s.eos
+			} else {
+				trailType = s.types[runEnd]
+				if trailType.in(AN, EN) {
+					trailType = R
+				}
+			}
+
+			var resolvedType Class
+			if leadType == trailType {
+				// Rule N1.
+				resolvedType = leadType
+			} else {
+				// Rule N2.
+				// Notice the embedding level of the run is used, not
+				// the paragraph embedding level.
+				resolvedType = typeForLevel(s.level)
+			}
+
+			setTypes(s.types[runStart:runEnd], resolvedType)
+
+			// skip over run of (former) neutrals
+			i = runEnd
+		}
+	}
+}
+
+func setLevels(levels []level, newLevel level) {
+	for i := range levels {
+		levels[i] = newLevel
+	}
+}
+
+func setTypes(types []Class, newType Class) {
+	for i := range types {
+		types[i] = newType
+	}
+}
+
+// 7) resolving implicit embedding levels Rules I1, I2.
+func (s *isolatingRunSequence) resolveImplicitLevels() {
+
+	// on entry, only these types can be in resultTypes
+	s.assertOnly(L, R, EN, AN)
+
+	s.resolvedLevels = make([]level, len(s.types))
+	setLevels(s.resolvedLevels, s.level)
+
+	if (s.level & 1) == 0 { // even level
+		for i, t := range s.types {
+			// Rule I1.
+			if t == L {
+				// no change
+			} else if t == R {
+				s.resolvedLevels[i] += 1
+			} else { // t == AN || t == EN
+				s.resolvedLevels[i] += 2
+			}
+		}
+	} else { // odd level
+		for i, t := range s.types {
+			// Rule I2.
+			if t == R {
+				// no change
+			} else { // t == L || t == AN || t == EN
+				s.resolvedLevels[i] += 1
+			}
+		}
+	}
+}
+
+// Applies the levels and types resolved in rules W1-I2 to the
+// resultLevels array.
+func (s *isolatingRunSequence) applyLevelsAndTypes() {
+	for i, x := range s.indexes {
+		s.p.resultTypes[x] = s.types[i]
+		s.p.resultLevels[x] = s.resolvedLevels[i]
+	}
+}
+
+// Return the limit of the run consisting only of the types in validSet
+// starting at index. This checks the value at index, and will return
+// index if that value is not in validSet.
+func (s *isolatingRunSequence) findRunLimit(index int, validSet ...Class) int {
+loop:
+	for ; index < len(s.types); index++ {
+		t := s.types[index]
+		for _, valid := range validSet {
+			if t == valid {
+				continue loop
+			}
+		}
+		return index // didn't find a match in validSet
+	}
+	return len(s.types)
+}
+
+// Algorithm validation. Assert that all values in types are in the
+// provided set.
+func (s *isolatingRunSequence) assertOnly(codes ...Class) {
+loop:
+	for i, t := range s.types {
+		for _, c := range codes {
+			if t == c {
+				continue loop
+			}
+		}
+		log.Panicf("invalid bidi code %v present in assertOnly at position %d", t, s.indexes[i])
+	}
+}
+
+// determineLevelRuns returns an array of level runs. Each level run is
+// described as an array of indexes into the input string.
+//
+// Determines the level runs. Rule X9 will be applied in determining the
+// runs, in the way that makes sure the characters that are supposed to be
+// removed are not included in the runs.
+func (p *paragraph) determineLevelRuns() [][]int {
+	run := []int{}
+	allRuns := [][]int{}
+	currentLevel := implicitLevel
+
+	for i := range p.initialTypes {
+		if !isRemovedByX9(p.initialTypes[i]) {
+			if p.resultLevels[i] != currentLevel {
+				// we just encountered a new run; wrap up last run
+				if currentLevel >= 0 { // only wrap it up if there was a run
+					allRuns = append(allRuns, run)
+					run = nil
+				}
+				// Start new run
+				currentLevel = p.resultLevels[i]
+			}
+			run = append(run, i)
+		}
+	}
+	// Wrap up the final run, if any
+	if len(run) > 0 {
+		allRuns = append(allRuns, run)
+	}
+	return allRuns
+}
+
+// Definition BD13. Determine isolating run sequences.
+func (p *paragraph) determineIsolatingRunSequences() []*isolatingRunSequence {
+	levelRuns := p.determineLevelRuns()
+
+	// Compute the run that each character belongs to
+	runForCharacter := make([]int, p.Len())
+	for i, run := range levelRuns {
+		for _, index := range run {
+			runForCharacter[index] = i
+		}
+	}
+
+	sequences := []*isolatingRunSequence{}
+
+	var currentRunSequence []int
+
+	for _, run := range levelRuns {
+		first := run[0]
+		if p.initialTypes[first] != PDI || p.matchingIsolateInitiator[first] == -1 {
+			currentRunSequence = nil
+			// int run = i;
+			for {
+				// Copy this level run into currentRunSequence
+				currentRunSequence = append(currentRunSequence, run...)
+
+				last := currentRunSequence[len(currentRunSequence)-1]
+				lastT := p.initialTypes[last]
+				if lastT.in(LRI, RLI, FSI) && p.matchingPDI[last] != p.Len() {
+					run = levelRuns[runForCharacter[p.matchingPDI[last]]]
+				} else {
+					break
+				}
+			}
+			sequences = append(sequences, p.isolatingRunSequence(currentRunSequence))
+		}
+	}
+	return sequences
+}
+
+// Assign level information to characters removed by rule X9. This is for
+// ease of relating the level information to the original input data. Note
+// that the levels assigned to these codes are arbitrary, they're chosen so
+// as to avoid breaking level runs.
+func (p *paragraph) assignLevelsToCharactersRemovedByX9() {
+	for i, t := range p.initialTypes {
+		if t.in(LRE, RLE, LRO, RLO, PDF, BN) {
+			p.resultTypes[i] = t
+			p.resultLevels[i] = -1
+		}
+	}
+	// now propagate forward the levels information (could have
+	// propagated backward, the main thing is not to introduce a level
+	// break where one doesn't already exist).
+
+	if p.resultLevels[0] == -1 {
+		p.resultLevels[0] = p.embeddingLevel
+	}
+	for i := 1; i < len(p.initialTypes); i++ {
+		if p.resultLevels[i] == -1 {
+			p.resultLevels[i] = p.resultLevels[i-1]
+		}
+	}
+	// Embedding information is for informational purposes only so need not be
+	// adjusted.
+}
+
+//
+// Output
+//
+
+// getLevels computes levels array breaking lines at offsets in linebreaks.
+// Rule L1.
+//
+// The linebreaks array must include at least one value. The values must be
+// in strictly increasing order (no duplicates) between 1 and the length of
+// the text, inclusive. The last value must be the length of the text.
+func (p *paragraph) getLevels(linebreaks []int) []level {
+	// Note that since the previous processing has removed all
+	// P, S, and WS values from resultTypes, the values referred to
+	// in these rules are the initial types, before any processing
+	// has been applied (including processing of overrides).
+	//
+	// This example implementation has reinserted explicit format codes
+	// and BN, in order that the levels array correspond to the
+	// initial text. Their final placement is not normative.
+	// These codes are treated like WS in this implementation,
+	// so they don't interrupt sequences of WS.
+
+	validateLineBreaks(linebreaks, p.Len())
+
+	result := append([]level(nil), p.resultLevels...)
+
+	// don't worry about linebreaks since if there is a break within
+	// a series of WS values preceding S, the linebreak itself
+	// causes the reset.
+	for i, t := range p.initialTypes {
+		if t.in(B, S) {
+			// Rule L1, clauses one and two.
+			result[i] = p.embeddingLevel
+
+			// Rule L1, clause three.
+			for j := i - 1; j >= 0; j-- {
+				if isWhitespace(p.initialTypes[j]) { // including format codes
+					result[j] = p.embeddingLevel
+				} else {
+					break
+				}
+			}
+		}
+	}
+
+	// Rule L1, clause four.
+	start := 0
+	for _, limit := range linebreaks {
+		for j := limit - 1; j >= start; j-- {
+			if isWhitespace(p.initialTypes[j]) { // including format codes
+				result[j] = p.embeddingLevel
+			} else {
+				break
+			}
+		}
+		start = limit
+	}
+
+	return result
+}
+
+// getReordering returns the reordering of lines from a visual index to a
+// logical index for line breaks at the given offsets.
+//
+// Lines are concatenated from left to right. So for example, the fifth
+// character from the left on the third line is
+//
+//	getReordering(linebreaks)[linebreaks[1] + 4]
+//
+// (linebreaks[1] is the position after the last character of the second
+// line, which is also the index of the first character on the third line,
+// and adding four gets the fifth character from the left).
+//
+// The linebreaks array must include at least one value. The values must be
+// in strictly increasing order (no duplicates) between 1 and the length of
+// the text, inclusive. The last value must be the length of the text.
+func (p *paragraph) getReordering(linebreaks []int) []int {
+	validateLineBreaks(linebreaks, p.Len())
+
+	return computeMultilineReordering(p.getLevels(linebreaks), linebreaks)
+}
+
+// Return multiline reordering array for a given level array. Reordering
+// does not occur across a line break.
+func computeMultilineReordering(levels []level, linebreaks []int) []int {
+	result := make([]int, len(levels))
+
+	start := 0
+	for _, limit := range linebreaks {
+		tempLevels := make([]level, limit-start)
+		copy(tempLevels, levels[start:])
+
+		for j, order := range computeReordering(tempLevels) {
+			result[start+j] = order + start
+		}
+		start = limit
+	}
+	return result
+}
+
+// Return reordering array for a given level array. This reorders a single
+// line. The reordering is a visual to logical map. For example, the
+// leftmost char is string.charAt(order[0]). Rule L2.
+func computeReordering(levels []level) []int {
+	result := make([]int, len(levels))
+	// initialize order
+	for i := range result {
+		result[i] = i
+	}
+
+	// locate highest level found on line.
+	// Note the rules say text, but no reordering across line bounds is
+	// performed, so this is sufficient.
+	highestLevel := level(0)
+	lowestOddLevel := level(maxDepth + 2)
+	for _, level := range levels {
+		if level > highestLevel {
+			highestLevel = level
+		}
+		if level&1 != 0 && level < lowestOddLevel {
+			lowestOddLevel = level
+		}
+	}
+
+	for level := highestLevel; level >= lowestOddLevel; level-- {
+		for i := 0; i < len(levels); i++ {
+			if levels[i] >= level {
+				// find range of text at or above this level
+				start := i
+				limit := i + 1
+				for limit < len(levels) && levels[limit] >= level {
+					limit++
+				}
+
+				for j, k := start, limit-1; j < k; j, k = j+1, k-1 {
+					result[j], result[k] = result[k], result[j]
+				}
+				// skip to end of level run
+				i = limit
+			}
+		}
+	}
+
+	return result
+}
+
+// isWhitespace reports whether the type is considered a whitespace type for the
+// line break rules.
+func isWhitespace(c Class) bool {
+	switch c {
+	case LRE, RLE, LRO, RLO, PDF, LRI, RLI, FSI, PDI, BN, WS:
+		return true
+	}
+	return false
+}
+
+// isRemovedByX9 reports whether the type is one of the types removed in X9.
+func isRemovedByX9(c Class) bool {
+	switch c {
+	case LRE, RLE, LRO, RLO, PDF, BN:
+		return true
+	}
+	return false
+}
+
+// typeForLevel reports the strong type (L or R) corresponding to the level.
+func typeForLevel(level level) Class {
+	if (level & 0x1) == 0 {
+		return L
+	}
+	return R
+}
+
+func validateTypes(types []Class) error {
+	if len(types) == 0 {
+		return fmt.Errorf("types is null")
+	}
+	for i, t := range types[:len(types)-1] {
+		if t == B {
+			return fmt.Errorf("B type before end of paragraph at index: %d", i)
+		}
+	}
+	return nil
+}
+
+func validateParagraphEmbeddingLevel(embeddingLevel level) error {
+	if embeddingLevel != implicitLevel &&
+		embeddingLevel != 0 &&
+		embeddingLevel != 1 {
+		return fmt.Errorf("illegal paragraph embedding level: %d", embeddingLevel)
+	}
+	return nil
+}
+
+func validateLineBreaks(linebreaks []int, textLength int) error {
+	prev := 0
+	for i, next := range linebreaks {
+		if next <= prev {
+			return fmt.Errorf("bad linebreak: %d at index: %d", next, i)
+		}
+		prev = next
+	}
+	if prev != textLength {
+		return fmt.Errorf("last linebreak was %d, want %d", prev, textLength)
+	}
+	return nil
+}
+
+func validatePbTypes(pairTypes []bracketType) error {
+	if len(pairTypes) == 0 {
+		return fmt.Errorf("pairTypes is null")
+	}
+	for i, pt := range pairTypes {
+		switch pt {
+		case bpNone, bpOpen, bpClose:
+		default:
+			return fmt.Errorf("illegal pairType value at %d: %v", i, pairTypes[i])
+		}
+	}
+	return nil
+}
+
+func validatePbValues(pairValues []rune, pairTypes []bracketType) error {
+	if pairValues == nil {
+		return fmt.Errorf("pairValues is null")
+	}
+	if len(pairTypes) != len(pairValues) {
+		return fmt.Errorf("pairTypes is different length from pairValues")
+	}
+	return nil
+}
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/bidi/prop.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/bidi/prop.go
index 7c9484e1f5..7c9484e1f5 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/bidi/prop.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/bidi/prop.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/bidi/tables13.0.0.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/bidi/tables13.0.0.go
index f248effae1..f248effae1 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/bidi/tables13.0.0.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/bidi/tables13.0.0.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/bidi/trieval.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/bidi/trieval.go
index 4c459c4b72..4c459c4b72 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/bidi/trieval.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/bidi/trieval.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/norm/composition.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/norm/composition.go
index e2087bce52..e2087bce52 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/norm/composition.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/norm/composition.go
diff --git a/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/norm/forminfo.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/norm/forminfo.go
new file mode 100644
index 0000000000..d69ccb4f97
--- /dev/null
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/norm/forminfo.go
@@ -0,0 +1,279 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package norm
+
+import "encoding/binary"
+
+// This file contains Form-specific logic and wrappers for data in tables.go.
+
+// Rune info is stored in a separate trie per composing form. A composing form
+// and its corresponding decomposing form share the same trie.  Each trie maps
+// a rune to a uint16. The values take two forms.  For v >= 0x8000:
+//   bits
+//   15:    1 (inverse of NFD_QC bit of qcInfo)
+//   13..7: qcInfo (see below). isYesD is always true (no decompostion).
+//    6..0: ccc (compressed CCC value).
+// For v < 0x8000, the respective rune has a decomposition and v is an index
+// into a byte array of UTF-8 decomposition sequences and additional info and
+// has the form:
+//    <header> <decomp_byte>* [<tccc> [<lccc>]]
+// The header contains the number of bytes in the decomposition (excluding this
+// length byte). The two most significant bits of this length byte correspond
+// to bit 5 and 4 of qcInfo (see below).  The byte sequence itself starts at v+1.
+// The byte sequence is followed by a trailing and leading CCC if the values
+// for these are not zero.  The value of v determines which ccc are appended
+// to the sequences.  For v < firstCCC, there are none, for v >= firstCCC,
+// the sequence is followed by a trailing ccc, and for v >= firstLeadingCC
+// there is an additional leading ccc. The value of tccc itself is the
+// trailing CCC shifted left 2 bits. The two least-significant bits of tccc
+// are the number of trailing non-starters.
+
+const (
+	qcInfoMask      = 0x3F // to clear all but the relevant bits in a qcInfo
+	headerLenMask   = 0x3F // extract the length value from the header byte
+	headerFlagsMask = 0xC0 // extract the qcInfo bits from the header byte
+)
+
+// Properties provides access to normalization properties of a rune.
+type Properties struct {
+	pos   uint8  // start position in reorderBuffer; used in composition.go
+	size  uint8  // length of UTF-8 encoding of this rune
+	ccc   uint8  // leading canonical combining class (ccc if not decomposition)
+	tccc  uint8  // trailing canonical combining class (ccc if not decomposition)
+	nLead uint8  // number of leading non-starters.
+	flags qcInfo // quick check flags
+	index uint16
+}
+
+// functions dispatchable per form
+type lookupFunc func(b input, i int) Properties
+
+// formInfo holds Form-specific functions and tables.
+type formInfo struct {
+	form                     Form
+	composing, compatibility bool // form type
+	info                     lookupFunc
+	nextMain                 iterFunc
+}
+
+var formTable = []*formInfo{{
+	form:          NFC,
+	composing:     true,
+	compatibility: false,
+	info:          lookupInfoNFC,
+	nextMain:      nextComposed,
+}, {
+	form:          NFD,
+	composing:     false,
+	compatibility: false,
+	info:          lookupInfoNFC,
+	nextMain:      nextDecomposed,
+}, {
+	form:          NFKC,
+	composing:     true,
+	compatibility: true,
+	info:          lookupInfoNFKC,
+	nextMain:      nextComposed,
+}, {
+	form:          NFKD,
+	composing:     false,
+	compatibility: true,
+	info:          lookupInfoNFKC,
+	nextMain:      nextDecomposed,
+}}
+
+// We do not distinguish between boundaries for NFC, NFD, etc. to avoid
+// unexpected behavior for the user.  For example, in NFD, there is a boundary
+// after 'a'.  However, 'a' might combine with modifiers, so from the application's
+// perspective it is not a good boundary. We will therefore always use the
+// boundaries for the combining variants.
+
+// BoundaryBefore returns true if this rune starts a new segment and
+// cannot combine with any rune on the left.
+func (p Properties) BoundaryBefore() bool {
+	if p.ccc == 0 && !p.combinesBackward() {
+		return true
+	}
+	// We assume that the CCC of the first character in a decomposition
+	// is always non-zero if different from info.ccc and that we can return
+	// false at this point. This is verified by maketables.
+	return false
+}
+
+// BoundaryAfter returns true if runes cannot combine with or otherwise
+// interact with this or previous runes.
+func (p Properties) BoundaryAfter() bool {
+	// TODO: loosen these conditions.
+	return p.isInert()
+}
+
+// We pack quick check data in 4 bits:
+//
+//	5:    Combines forward  (0 == false, 1 == true)
+//	4..3: NFC_QC Yes(00), No (10), or Maybe (11)
+//	2:    NFD_QC Yes (0) or No (1). No also means there is a decomposition.
+//	1..0: Number of trailing non-starters.
+//
+// When all 4 bits are zero, the character is inert, meaning it is never
+// influenced by normalization.
+type qcInfo uint8
+
+func (p Properties) isYesC() bool { return p.flags&0x10 == 0 }
+func (p Properties) isYesD() bool { return p.flags&0x4 == 0 }
+
+func (p Properties) combinesForward() bool  { return p.flags&0x20 != 0 }
+func (p Properties) combinesBackward() bool { return p.flags&0x8 != 0 } // == isMaybe
+func (p Properties) hasDecomposition() bool { return p.flags&0x4 != 0 } // == isNoD
+
+func (p Properties) isInert() bool {
+	return p.flags&qcInfoMask == 0 && p.ccc == 0
+}
+
+func (p Properties) multiSegment() bool {
+	return p.index >= firstMulti && p.index < endMulti
+}
+
+func (p Properties) nLeadingNonStarters() uint8 {
+	return p.nLead
+}
+
+func (p Properties) nTrailingNonStarters() uint8 {
+	return uint8(p.flags & 0x03)
+}
+
+// Decomposition returns the decomposition for the underlying rune
+// or nil if there is none.
+func (p Properties) Decomposition() []byte {
+	// TODO: create the decomposition for Hangul?
+	if p.index == 0 {
+		return nil
+	}
+	i := p.index
+	n := decomps[i] & headerLenMask
+	i++
+	return decomps[i : i+uint16(n)]
+}
+
+// Size returns the length of UTF-8 encoding of the rune.
+func (p Properties) Size() int {
+	return int(p.size)
+}
+
+// CCC returns the canonical combining class of the underlying rune.
+func (p Properties) CCC() uint8 {
+	if p.index >= firstCCCZeroExcept {
+		return 0
+	}
+	return ccc[p.ccc]
+}
+
+// LeadCCC returns the CCC of the first rune in the decomposition.
+// If there is no decomposition, LeadCCC equals CCC.
+func (p Properties) LeadCCC() uint8 {
+	return ccc[p.ccc]
+}
+
+// TrailCCC returns the CCC of the last rune in the decomposition.
+// If there is no decomposition, TrailCCC equals CCC.
+func (p Properties) TrailCCC() uint8 {
+	return ccc[p.tccc]
+}
+
+func buildRecompMap() {
+	recompMap = make(map[uint32]rune, len(recompMapPacked)/8)
+	var buf [8]byte
+	for i := 0; i < len(recompMapPacked); i += 8 {
+		copy(buf[:], recompMapPacked[i:i+8])
+		key := binary.BigEndian.Uint32(buf[:4])
+		val := binary.BigEndian.Uint32(buf[4:])
+		recompMap[key] = rune(val)
+	}
+}
+
+// Recomposition
+// We use 32-bit keys instead of 64-bit for the two codepoint keys.
+// This clips off the bits of three entries, but we know this will not
+// result in a collision. In the unlikely event that changes to
+// UnicodeData.txt introduce collisions, the compiler will catch it.
+// Note that the recomposition map for NFC and NFKC are identical.
+
+// combine returns the combined rune or 0 if it doesn't exist.
+//
+// The caller is responsible for calling
+// recompMapOnce.Do(buildRecompMap) sometime before this is called.
+func combine(a, b rune) rune {
+	key := uint32(uint16(a))<<16 + uint32(uint16(b))
+	if recompMap == nil {
+		panic("caller error") // see func comment
+	}
+	return recompMap[key]
+}
+
+func lookupInfoNFC(b input, i int) Properties {
+	v, sz := b.charinfoNFC(i)
+	return compInfo(v, sz)
+}
+
+func lookupInfoNFKC(b input, i int) Properties {
+	v, sz := b.charinfoNFKC(i)
+	return compInfo(v, sz)
+}
+
+// Properties returns properties for the first rune in s.
+func (f Form) Properties(s []byte) Properties {
+	if f == NFC || f == NFD {
+		return compInfo(nfcData.lookup(s))
+	}
+	return compInfo(nfkcData.lookup(s))
+}
+
+// PropertiesString returns properties for the first rune in s.
+func (f Form) PropertiesString(s string) Properties {
+	if f == NFC || f == NFD {
+		return compInfo(nfcData.lookupString(s))
+	}
+	return compInfo(nfkcData.lookupString(s))
+}
+
+// compInfo converts the information contained in v and sz
+// to a Properties.  See the comment at the top of the file
+// for more information on the format.
+func compInfo(v uint16, sz int) Properties {
+	if v == 0 {
+		return Properties{size: uint8(sz)}
+	} else if v >= 0x8000 {
+		p := Properties{
+			size:  uint8(sz),
+			ccc:   uint8(v),
+			tccc:  uint8(v),
+			flags: qcInfo(v >> 8),
+		}
+		if p.ccc > 0 || p.combinesBackward() {
+			p.nLead = uint8(p.flags & 0x3)
+		}
+		return p
+	}
+	// has decomposition
+	h := decomps[v]
+	f := (qcInfo(h&headerFlagsMask) >> 2) | 0x4
+	p := Properties{size: uint8(sz), flags: f, index: v}
+	if v >= firstCCC {
+		v += uint16(h&headerLenMask) + 1
+		c := decomps[v]
+		p.tccc = c >> 2
+		p.flags |= qcInfo(c & 0x3)
+		if v >= firstLeadingCCC {
+			p.nLead = c & 0x3
+			if v >= firstStarterWithNLead {
+				// We were tricked. Remove the decomposition.
+				p.flags &= 0x03
+				p.index = 0
+				return p
+			}
+			p.ccc = decomps[v+1]
+		}
+	}
+	return p
+}
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/norm/input.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/norm/input.go
index 479e35bc25..479e35bc25 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/norm/input.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/norm/input.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/norm/iter.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/norm/iter.go
index 417c6b2689..417c6b2689 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/norm/iter.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/norm/iter.go
diff --git a/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/norm/normalize.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/norm/normalize.go
new file mode 100644
index 0000000000..4747ad07a8
--- /dev/null
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/norm/normalize.go
@@ -0,0 +1,610 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Note: the file data_test.go that is generated should not be checked in.
+//go:generate go run maketables.go triegen.go
+//go:generate go test -tags test
+
+// Package norm contains types and functions for normalizing Unicode strings.
+package norm // import "golang.org/x/text/unicode/norm"
+
+import (
+	"unicode/utf8"
+
+	"golang.org/x/text/transform"
+)
+
+// A Form denotes a canonical representation of Unicode code points.
+// The Unicode-defined normalization and equivalence forms are:
+//
+//	NFC   Unicode Normalization Form C
+//	NFD   Unicode Normalization Form D
+//	NFKC  Unicode Normalization Form KC
+//	NFKD  Unicode Normalization Form KD
+//
+// For a Form f, this documentation uses the notation f(x) to mean
+// the bytes or string x converted to the given form.
+// A position n in x is called a boundary if conversion to the form can
+// proceed independently on both sides:
+//
+//	f(x) == append(f(x[0:n]), f(x[n:])...)
+//
+// References: https://unicode.org/reports/tr15/ and
+// https://unicode.org/notes/tn5/.
+type Form int
+
+const (
+	NFC Form = iota
+	NFD
+	NFKC
+	NFKD
+)
+
+// Bytes returns f(b). May return b if f(b) = b.
+func (f Form) Bytes(b []byte) []byte {
+	src := inputBytes(b)
+	ft := formTable[f]
+	n, ok := ft.quickSpan(src, 0, len(b), true)
+	if ok {
+		return b
+	}
+	out := make([]byte, n, len(b))
+	copy(out, b[0:n])
+	rb := reorderBuffer{f: *ft, src: src, nsrc: len(b), out: out, flushF: appendFlush}
+	return doAppendInner(&rb, n)
+}
+
+// String returns f(s).
+func (f Form) String(s string) string {
+	src := inputString(s)
+	ft := formTable[f]
+	n, ok := ft.quickSpan(src, 0, len(s), true)
+	if ok {
+		return s
+	}
+	out := make([]byte, n, len(s))
+	copy(out, s[0:n])
+	rb := reorderBuffer{f: *ft, src: src, nsrc: len(s), out: out, flushF: appendFlush}
+	return string(doAppendInner(&rb, n))
+}
+
+// IsNormal returns true if b == f(b).
+func (f Form) IsNormal(b []byte) bool {
+	src := inputBytes(b)
+	ft := formTable[f]
+	bp, ok := ft.quickSpan(src, 0, len(b), true)
+	if ok {
+		return true
+	}
+	rb := reorderBuffer{f: *ft, src: src, nsrc: len(b)}
+	rb.setFlusher(nil, cmpNormalBytes)
+	for bp < len(b) {
+		rb.out = b[bp:]
+		if bp = decomposeSegment(&rb, bp, true); bp < 0 {
+			return false
+		}
+		bp, _ = rb.f.quickSpan(rb.src, bp, len(b), true)
+	}
+	return true
+}
+
+func cmpNormalBytes(rb *reorderBuffer) bool {
+	b := rb.out
+	for i := 0; i < rb.nrune; i++ {
+		info := rb.rune[i]
+		if int(info.size) > len(b) {
+			return false
+		}
+		p := info.pos
+		pe := p + info.size
+		for ; p < pe; p++ {
+			if b[0] != rb.byte[p] {
+				return false
+			}
+			b = b[1:]
+		}
+	}
+	return true
+}
+
+// IsNormalString returns true if s == f(s).
+func (f Form) IsNormalString(s string) bool {
+	src := inputString(s)
+	ft := formTable[f]
+	bp, ok := ft.quickSpan(src, 0, len(s), true)
+	if ok {
+		return true
+	}
+	rb := reorderBuffer{f: *ft, src: src, nsrc: len(s)}
+	rb.setFlusher(nil, func(rb *reorderBuffer) bool {
+		for i := 0; i < rb.nrune; i++ {
+			info := rb.rune[i]
+			if bp+int(info.size) > len(s) {
+				return false
+			}
+			p := info.pos
+			pe := p + info.size
+			for ; p < pe; p++ {
+				if s[bp] != rb.byte[p] {
+					return false
+				}
+				bp++
+			}
+		}
+		return true
+	})
+	for bp < len(s) {
+		if bp = decomposeSegment(&rb, bp, true); bp < 0 {
+			return false
+		}
+		bp, _ = rb.f.quickSpan(rb.src, bp, len(s), true)
+	}
+	return true
+}
+
+// patchTail fixes a case where a rune may be incorrectly normalized
+// if it is followed by illegal continuation bytes. It returns the
+// patched buffer and whether the decomposition is still in progress.
+func patchTail(rb *reorderBuffer) bool {
+	info, p := lastRuneStart(&rb.f, rb.out)
+	if p == -1 || info.size == 0 {
+		return true
+	}
+	end := p + int(info.size)
+	extra := len(rb.out) - end
+	if extra > 0 {
+		// Potentially allocating memory. However, this only
+		// happens with ill-formed UTF-8.
+		x := make([]byte, 0)
+		x = append(x, rb.out[len(rb.out)-extra:]...)
+		rb.out = rb.out[:end]
+		decomposeToLastBoundary(rb)
+		rb.doFlush()
+		rb.out = append(rb.out, x...)
+		return false
+	}
+	buf := rb.out[p:]
+	rb.out = rb.out[:p]
+	decomposeToLastBoundary(rb)
+	if s := rb.ss.next(info); s == ssStarter {
+		rb.doFlush()
+		rb.ss.first(info)
+	} else if s == ssOverflow {
+		rb.doFlush()
+		rb.insertCGJ()
+		rb.ss = 0
+	}
+	rb.insertUnsafe(inputBytes(buf), 0, info)
+	return true
+}
+
+func appendQuick(rb *reorderBuffer, i int) int {
+	if rb.nsrc == i {
+		return i
+	}
+	end, _ := rb.f.quickSpan(rb.src, i, rb.nsrc, true)
+	rb.out = rb.src.appendSlice(rb.out, i, end)
+	return end
+}
+
+// Append returns f(append(out, b...)).
+// The buffer out must be nil, empty, or equal to f(out).
+func (f Form) Append(out []byte, src ...byte) []byte {
+	return f.doAppend(out, inputBytes(src), len(src))
+}
+
+func (f Form) doAppend(out []byte, src input, n int) []byte {
+	if n == 0 {
+		return out
+	}
+	ft := formTable[f]
+	// Attempt to do a quickSpan first so we can avoid initializing the reorderBuffer.
+	if len(out) == 0 {
+		p, _ := ft.quickSpan(src, 0, n, true)
+		out = src.appendSlice(out, 0, p)
+		if p == n {
+			return out
+		}
+		rb := reorderBuffer{f: *ft, src: src, nsrc: n, out: out, flushF: appendFlush}
+		return doAppendInner(&rb, p)
+	}
+	rb := reorderBuffer{f: *ft, src: src, nsrc: n}
+	return doAppend(&rb, out, 0)
+}
+
+func doAppend(rb *reorderBuffer, out []byte, p int) []byte {
+	rb.setFlusher(out, appendFlush)
+	src, n := rb.src, rb.nsrc
+	doMerge := len(out) > 0
+	if q := src.skipContinuationBytes(p); q > p {
+		// Move leading non-starters to destination.
+		rb.out = src.appendSlice(rb.out, p, q)
+		p = q
+		doMerge = patchTail(rb)
+	}
+	fd := &rb.f
+	if doMerge {
+		var info Properties
+		if p < n {
+			info = fd.info(src, p)
+			if !info.BoundaryBefore() || info.nLeadingNonStarters() > 0 {
+				if p == 0 {
+					decomposeToLastBoundary(rb)
+				}
+				p = decomposeSegment(rb, p, true)
+			}
+		}
+		if info.size == 0 {
+			rb.doFlush()
+			// Append incomplete UTF-8 encoding.
+			return src.appendSlice(rb.out, p, n)
+		}
+		if rb.nrune > 0 {
+			return doAppendInner(rb, p)
+		}
+	}
+	p = appendQuick(rb, p)
+	return doAppendInner(rb, p)
+}
+
+func doAppendInner(rb *reorderBuffer, p int) []byte {
+	for n := rb.nsrc; p < n; {
+		p = decomposeSegment(rb, p, true)
+		p = appendQuick(rb, p)
+	}
+	return rb.out
+}
+
+// AppendString returns f(append(out, []byte(s))).
+// The buffer out must be nil, empty, or equal to f(out).
+func (f Form) AppendString(out []byte, src string) []byte {
+	return f.doAppend(out, inputString(src), len(src))
+}
+
+// QuickSpan returns a boundary n such that b[0:n] == f(b[0:n]).
+// It is not guaranteed to return the largest such n.
+func (f Form) QuickSpan(b []byte) int {
+	n, _ := formTable[f].quickSpan(inputBytes(b), 0, len(b), true)
+	return n
+}
+
+// Span implements transform.SpanningTransformer. It returns a boundary n such
+// that b[0:n] == f(b[0:n]). It is not guaranteed to return the largest such n.
+func (f Form) Span(b []byte, atEOF bool) (n int, err error) {
+	n, ok := formTable[f].quickSpan(inputBytes(b), 0, len(b), atEOF)
+	if n < len(b) {
+		if !ok {
+			err = transform.ErrEndOfSpan
+		} else {
+			err = transform.ErrShortSrc
+		}
+	}
+	return n, err
+}
+
+// SpanString returns a boundary n such that s[0:n] == f(s[0:n]).
+// It is not guaranteed to return the largest such n.
+func (f Form) SpanString(s string, atEOF bool) (n int, err error) {
+	n, ok := formTable[f].quickSpan(inputString(s), 0, len(s), atEOF)
+	if n < len(s) {
+		if !ok {
+			err = transform.ErrEndOfSpan
+		} else {
+			err = transform.ErrShortSrc
+		}
+	}
+	return n, err
+}
+
+// quickSpan returns a boundary n such that src[0:n] == f(src[0:n]) and
+// whether any non-normalized parts were found. If atEOF is false, n will
+// not point past the last segment if this segment might be become
+// non-normalized by appending other runes.
+func (f *formInfo) quickSpan(src input, i, end int, atEOF bool) (n int, ok bool) {
+	var lastCC uint8
+	ss := streamSafe(0)
+	lastSegStart := i
+	for n = end; i < n; {
+		if j := src.skipASCII(i, n); i != j {
+			i = j
+			lastSegStart = i - 1
+			lastCC = 0
+			ss = 0
+			continue
+		}
+		info := f.info(src, i)
+		if info.size == 0 {
+			if atEOF {
+				// include incomplete runes
+				return n, true
+			}
+			return lastSegStart, true
+		}
+		// This block needs to be before the next, because it is possible to
+		// have an overflow for runes that are starters (e.g. with U+FF9E).
+		switch ss.next(info) {
+		case ssStarter:
+			lastSegStart = i
+		case ssOverflow:
+			return lastSegStart, false
+		case ssSuccess:
+			if lastCC > info.ccc {
+				return lastSegStart, false
+			}
+		}
+		if f.composing {
+			if !info.isYesC() {
+				break
+			}
+		} else {
+			if !info.isYesD() {
+				break
+			}
+		}
+		lastCC = info.ccc
+		i += int(info.size)
+	}
+	if i == n {
+		if !atEOF {
+			n = lastSegStart
+		}
+		return n, true
+	}
+	return lastSegStart, false
+}
+
+// QuickSpanString returns a boundary n such that s[0:n] == f(s[0:n]).
+// It is not guaranteed to return the largest such n.
+func (f Form) QuickSpanString(s string) int {
+	n, _ := formTable[f].quickSpan(inputString(s), 0, len(s), true)
+	return n
+}
+
+// FirstBoundary returns the position i of the first boundary in b
+// or -1 if b contains no boundary.
+func (f Form) FirstBoundary(b []byte) int {
+	return f.firstBoundary(inputBytes(b), len(b))
+}
+
+func (f Form) firstBoundary(src input, nsrc int) int {
+	i := src.skipContinuationBytes(0)
+	if i >= nsrc {
+		return -1
+	}
+	fd := formTable[f]
+	ss := streamSafe(0)
+	// We should call ss.first here, but we can't as the first rune is
+	// skipped already. This means FirstBoundary can't really determine
+	// CGJ insertion points correctly. Luckily it doesn't have to.
+	for {
+		info := fd.info(src, i)
+		if info.size == 0 {
+			return -1
+		}
+		if s := ss.next(info); s != ssSuccess {
+			return i
+		}
+		i += int(info.size)
+		if i >= nsrc {
+			if !info.BoundaryAfter() && !ss.isMax() {
+				return -1
+			}
+			return nsrc
+		}
+	}
+}
+
+// FirstBoundaryInString returns the position i of the first boundary in s
+// or -1 if s contains no boundary.
+func (f Form) FirstBoundaryInString(s string) int {
+	return f.firstBoundary(inputString(s), len(s))
+}
+
+// NextBoundary reports the index of the boundary between the first and next
+// segment in b or -1 if atEOF is false and there are not enough bytes to
+// determine this boundary.
+func (f Form) NextBoundary(b []byte, atEOF bool) int {
+	return f.nextBoundary(inputBytes(b), len(b), atEOF)
+}
+
+// NextBoundaryInString reports the index of the boundary between the first and
+// next segment in b or -1 if atEOF is false and there are not enough bytes to
+// determine this boundary.
+func (f Form) NextBoundaryInString(s string, atEOF bool) int {
+	return f.nextBoundary(inputString(s), len(s), atEOF)
+}
+
+func (f Form) nextBoundary(src input, nsrc int, atEOF bool) int {
+	if nsrc == 0 {
+		if atEOF {
+			return 0
+		}
+		return -1
+	}
+	fd := formTable[f]
+	info := fd.info(src, 0)
+	if info.size == 0 {
+		if atEOF {
+			return 1
+		}
+		return -1
+	}
+	ss := streamSafe(0)
+	ss.first(info)
+
+	for i := int(info.size); i < nsrc; i += int(info.size) {
+		info = fd.info(src, i)
+		if info.size == 0 {
+			if atEOF {
+				return i
+			}
+			return -1
+		}
+		// TODO: Using streamSafe to determine the boundary isn't the same as
+		// using BoundaryBefore. Determine which should be used.
+		if s := ss.next(info); s != ssSuccess {
+			return i
+		}
+	}
+	if !atEOF && !info.BoundaryAfter() && !ss.isMax() {
+		return -1
+	}
+	return nsrc
+}
+
+// LastBoundary returns the position i of the last boundary in b
+// or -1 if b contains no boundary.
+func (f Form) LastBoundary(b []byte) int {
+	return lastBoundary(formTable[f], b)
+}
+
+func lastBoundary(fd *formInfo, b []byte) int {
+	i := len(b)
+	info, p := lastRuneStart(fd, b)
+	if p == -1 {
+		return -1
+	}
+	if info.size == 0 { // ends with incomplete rune
+		if p == 0 { // starts with incomplete rune
+			return -1
+		}
+		i = p
+		info, p = lastRuneStart(fd, b[:i])
+		if p == -1 { // incomplete UTF-8 encoding or non-starter bytes without a starter
+			return i
+		}
+	}
+	if p+int(info.size) != i { // trailing non-starter bytes: illegal UTF-8
+		return i
+	}
+	if info.BoundaryAfter() {
+		return i
+	}
+	ss := streamSafe(0)
+	v := ss.backwards(info)
+	for i = p; i >= 0 && v != ssStarter; i = p {
+		info, p = lastRuneStart(fd, b[:i])
+		if v = ss.backwards(info); v == ssOverflow {
+			break
+		}
+		if p+int(info.size) != i {
+			if p == -1 { // no boundary found
+				return -1
+			}
+			return i // boundary after an illegal UTF-8 encoding
+		}
+	}
+	return i
+}
+
+// decomposeSegment scans the first segment in src into rb. It inserts 0x034f
+// (Grapheme Joiner) when it encounters a sequence of more than 30 non-starters
+// and returns the number of bytes consumed from src or iShortDst or iShortSrc.
+func decomposeSegment(rb *reorderBuffer, sp int, atEOF bool) int {
+	// Force one character to be consumed.
+	info := rb.f.info(rb.src, sp)
+	if info.size == 0 {
+		return 0
+	}
+	if s := rb.ss.next(info); s == ssStarter {
+		// TODO: this could be removed if we don't support merging.
+		if rb.nrune > 0 {
+			goto end
+		}
+	} else if s == ssOverflow {
+		rb.insertCGJ()
+		goto end
+	}
+	if err := rb.insertFlush(rb.src, sp, info); err != iSuccess {
+		return int(err)
+	}
+	for {
+		sp += int(info.size)
+		if sp >= rb.nsrc {
+			if !atEOF && !info.BoundaryAfter() {
+				return int(iShortSrc)
+			}
+			break
+		}
+		info = rb.f.info(rb.src, sp)
+		if info.size == 0 {
+			if !atEOF {
+				return int(iShortSrc)
+			}
+			break
+		}
+		if s := rb.ss.next(info); s == ssStarter {
+			break
+		} else if s == ssOverflow {
+			rb.insertCGJ()
+			break
+		}
+		if err := rb.insertFlush(rb.src, sp, info); err != iSuccess {
+			return int(err)
+		}
+	}
+end:
+	if !rb.doFlush() {
+		return int(iShortDst)
+	}
+	return sp
+}
+
+// lastRuneStart returns the runeInfo and position of the last
+// rune in buf or the zero runeInfo and -1 if no rune was found.
+func lastRuneStart(fd *formInfo, buf []byte) (Properties, int) {
+	p := len(buf) - 1
+	for ; p >= 0 && !utf8.RuneStart(buf[p]); p-- {
+	}
+	if p < 0 {
+		return Properties{}, -1
+	}
+	return fd.info(inputBytes(buf), p), p
+}
+
+// decomposeToLastBoundary finds an open segment at the end of the buffer
+// and scans it into rb. Returns the buffer minus the last segment.
+func decomposeToLastBoundary(rb *reorderBuffer) {
+	fd := &rb.f
+	info, i := lastRuneStart(fd, rb.out)
+	if int(info.size) != len(rb.out)-i {
+		// illegal trailing continuation bytes
+		return
+	}
+	if info.BoundaryAfter() {
+		return
+	}
+	var add [maxNonStarters + 1]Properties // stores runeInfo in reverse order
+	padd := 0
+	ss := streamSafe(0)
+	p := len(rb.out)
+	for {
+		add[padd] = info
+		v := ss.backwards(info)
+		if v == ssOverflow {
+			// Note that if we have an overflow, it the string we are appending to
+			// is not correctly normalized. In this case the behavior is undefined.
+			break
+		}
+		padd++
+		p -= int(info.size)
+		if v == ssStarter || p < 0 {
+			break
+		}
+		info, i = lastRuneStart(fd, rb.out[:p])
+		if int(info.size) != p-i {
+			break
+		}
+	}
+	rb.ss = ss
+	// Copy bytes for insertion as we may need to overwrite rb.out.
+	var buf [maxBufferSize * utf8.UTFMax]byte
+	cp := buf[:copy(buf[:], rb.out[p:])]
+	rb.out = rb.out[:p]
+	for padd--; padd >= 0; padd-- {
+		info = add[padd]
+		rb.insertUnsafe(inputBytes(cp), 0, info)
+		cp = cp[info.size:]
+	}
+}
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/norm/readwriter.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/norm/readwriter.go
index b38096f5ca..b38096f5ca 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/norm/readwriter.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/norm/readwriter.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/norm/tables13.0.0.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/norm/tables13.0.0.go
index 96a130d30e..96a130d30e 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/norm/tables13.0.0.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/norm/tables13.0.0.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/norm/transform.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/norm/transform.go
index a1d366ae48..a1d366ae48 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/norm/transform.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/norm/transform.go
diff --git a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/norm/trie.go b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/norm/trie.go
index 423386bf43..423386bf43 100644
--- a/contrib/go/_std_1.18/src/vendor/golang.org/x/text/unicode/norm/trie.go
+++ b/contrib/go/_std_1.19/src/vendor/golang.org/x/text/unicode/norm/trie.go